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Sample records for acid citrate dextrose

  1. Gender and chronological age affect erythrocyte membrane oxidative indices in citrate phosphate dextrose adenine-formula 1 (CPDA-1) blood bank storage condition.

    PubMed

    Erman, Hayriye; Aksu, Uğur; Belce, Ahmet; Atukeren, Pınar; Uzun, Duygu; Cebe, Tamer; Kansu, Ahmet D; Gelişgen, Remisa; Uslu, Ezel; Aydın, Seval; Çakatay, Ufuk

    2016-07-01

    It is well known that in vitro storage lesions lead to membrane dysfunction and decreased number of functional erythrocytes. As erythrocytes get older, in storage media as well as in peripheral circulation, they undergo a variety of biochemical changes. In our study, the erythrocytes with different age groups in citrate phosphate dextrose adenine-formula 1 (CPDA-1) storage solution were used in order to investigate the possible effect of gender factor on oxidative damage. Oxidative damage biomarkers in erythrocyte membranes such as ferric reducing antioxidant power, pro-oxidant-antioxidant balance, protein-bound advance glycation end products, and sialic acid were analyzed. Current study reveals that change in membrane redox status during blood-bank storage condition also depends on both gender depended homeostatic factors and the presence of CPDA-1. During the storage period in CPDA-1, erythrocytes from the male donors are mostly affected by free radical-mediated oxidative stress but erythrocytes obtained from females are severely affected by glyoxidative stress.

  2. 77 FR 24461 - Citric Acid and Certain Citrate Salts From Canada: Final Results of Antidumping Duty...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-24

    ... all grades and granulation sizes of citric acid, sodium citrate, and potassium citrate in their... blends of citric acid, sodium citrate, and potassium citrate; as well as blends with other ingredients, such as sugar, where the unblended form(s) of citric acid, sodium citrate, and potassium...

  3. 78 FR 34338 - Citric Acid and Certain Citrate Salts From Canada: Preliminary Results of Antidumping Duty...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-07

    ... International Trade Administration Citric Acid and Certain Citrate Salts From Canada: Preliminary Results of... administrative review of the antidumping duty order on citric acid and certain citrate salts (citric acid) from... is citric acid and certain citrate salts. The product is currently classified in the...

  4. 77 FR 47370 - Citric Acid and Certain Citrate Salts from the People's Republic of China: Intent To Rescind...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-08

    ..., sodium citrate, and potassium citrate in their unblended forms, whether dry or in solution, and regardless of packaging type. The scope also includes blends of citric acid, sodium citrate, and potassium... acid, sodium citrate, and potassium citrate constitute 40 percent or more, by weight, of the blend....

  5. 77 FR 6061 - Citric Acid and Certain Citrate Salts From Canada: Preliminary Results of Antidumping Duty...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-07

    ... International Trade Administration Citric Acid and Certain Citrate Salts From Canada: Preliminary Results of... administrative review of the antidumping duty order on citric acid and certain citrate salts (citric acid) from... initiation of an administrative review of the antidumping duty order on citric acid from Canada with...

  6. 76 FR 5782 - Citric Acid and Certain Citrate Salts From Canada: Preliminary Results of Antidumping Duty...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-02

    ... International Trade Administration Citric Acid and Certain Citrate Salts From Canada: Preliminary Results of... administrative review of the antidumping duty order on citric acid and certain citrate salts (citric acid) from... citric acid from Canada with respect to JBL Canada covering the period November 20, 2008, through May...

  7. Serum amino acid concentrations in patients receiving total parenteral nutrition with an amino acid plus dextrose mixture.

    PubMed

    Philcox, J C; Hartley, T F; Worthley, L I; Thomas, D W

    1984-01-01

    The results of monitoring the serum amino acid concentrations during three infusion regimens using a 5:4 mixture of 70% glucose and the synthetic L-amino acid solution, Synthamin 17 (Travasol) are reported. Twelve stabilized patients received continuous total parenteral nutrition (TPN), eight of whom were subsequently placed on a second regimen of cyclical feeding. A separate group of five patients was infused with amino acids, both with and without simultaneous glucose. The serum amino acid concentrations indicated that the supply of valine, leucine, isoleucine, lysine, and histidine, and the synthesis of taurine from the infused methionine was suboptimal, particularly if the period of TPN was prolonged. The synthesis of tyrosine from phenylalanine appeared to be inversely proportional to the infusion rate of the TPN mixture, in particular the glucose component, resulting in depressed tyrosine and increased phenylalanine concentrations in serum during continuous iv nutrition. Cyclical infusions, on the other hand, permitted the tyrosine and phenylalanine concentrations to return to normal during the noninfusion stage of the cycle. Amino acid measurements enabled us to design an amino acids additive mixture which normalized the serum concentrations in three long-term home parenteral nutrition patients. As a result of these investigations serum amino acid measurements are used routinely to monitor the efficacy of TPN and accommodate any specific amino acid requirements of individual patients.

  8. Effects of dextrose and lipopolysaccharide on the corrosion behavior of a Ti-6Al-4V alloy with a smooth surface or treated with double-acid-etching.

    PubMed

    Faverani, Leonardo P; Assunção, Wirley G; de Carvalho, Paulo Sérgio P; Yuan, Judy Chia-Chun; Sukotjo, Cortino; Mathew, Mathew T; Barao, Valentim A

    2014-01-01

    Diabetes and infections are associated with a high risk of implant failure. However, the effects of such conditions on the electrochemical stability of titanium materials remain unclear. This study evaluated the corrosion behavior of a Ti-6Al-4V alloy, with a smooth surface or conditioned by double-acid-etching, in simulated body fluid with different concentrations of dextrose and lipopolysaccharide. For the electrochemical assay, the open-circuit-potential, electrochemical impedance spectroscopy, and potentiodynamic test were used. The disc surfaces were characterized by scanning electron microscopy and atomic force microscopy. Their surface roughness and Vickers microhardness were also tested. The quantitative data were analyzed by Pearson's correlation and independent t-tests (α = 0.05). In the corrosion parameters, there was a strong lipopolysaccharide correlation with the Ipass (passivation current density), Cdl (double-layer capacitance), and Rp (polarization resistance) values (p<0.05) for the Ti-6Al-4V alloy with surface treatment by double-acid-etching. The combination of dextrose and lipopolysaccharide was correlated with the Icorr (corrosion current density) and Ipass (p<0.05). The acid-treated groups showed a significant increase in Cdl values and reduced Rp values (p<0.05, t-test). According to the topography, there was an increase in surface roughness (R2 = 0.726, p<0.0001 for the smooth surface; R2 = 0.405, p = 0.036 for the double-acid-etching-treated surface). The microhardness of the smooth Ti-6Al-4V alloy decreased (p<0.05) and that of the treated Ti-6Al-4V alloy increased (p<0.0001). Atomic force microscopy showed changes in the microstructure of the Ti-6Al-4V alloy by increasing the surface thickness mainly in the group associated with dextrose and lipopolysaccharide. The combination of dextrose and lipopolysaccharide affected the corrosion behavior of the Ti-6Al-4V alloy surface treated with double-acid-etching. However, no

  9. Ileal Endogenous Amino Acid Flow Response to Nitrogen-free Diets with Differing Ratios of Corn Starch to Dextrose in Pigs

    PubMed Central

    Kong, C.; Ragland, D.; Adeola, O.

    2014-01-01

    The objective of this study was to determine the responses in the digestibility of dry matter (DM) and amino acid (AA) composition of ileal endogenous flow (IEF) of pigs (initial body weight, 69.1±6.46 kg) fed N-free diets (NFD) formulated with different ratios of corn starch to dextrose. Fifteen pigs fitted with a T-cannula at the distal ileum were fed 5 diets according to a triplicated 5×2 incomplete Latin-square design. Each period consisted of a 5-d adjustment period and 2 d of ileal digesta collection for 12 h on each of d 6 and 7 and between each period, there was a 5-d recovery period to avoid abnormal weight loss. The ratios of corn starch to dextrose investigated were 0:879, 293:586, 586:293, 779:100, and 879:0 for diet numbers 1, 2, 3, 4 and 5, respectively, and chromic oxide (5 g/kg) was used as an indigestible index. Ileal DM digestibility was greater in Diet 1 than that in Diet 4 (89.5% vs 87.3%, p<0.01) but they were not different from Diet 2, 3, or 5. The IEF for most of indispensable AA were not different among diets with the exception of Met, in which a lack of corn starch or dextrose gave lower (p = 0.028) IEF of Met than diets containing corn starch and dextrose. Likewise, the dispensable AA and total AA in the IEF did not differ among diets. The respective IEF of AA (mg/kg of dry matter intake) in pigs fed Diets 1, 2, 3, 4, or 5 were 301, 434, 377, 477,or 365 for Lys, 61, 89, 71, 87, or 61 for Met, and 477, 590, 472, 520, or 436 for Thr. Proline was the most abundant AA in the IEF followed by Gly, Glu, and Asp and together accounted for approximately 50% of the total ileal AA flows of pigs fed NFD. In conclusion, the variation in proportion of corn starch and dextrose in a NFD does not largely affect estimates of IEF of N and AA for growing-finishing pigs. PMID:25083106

  10. 78 FR 64914 - Citric Acid and Certain Citrate Salts From Canada: Final Results of Antidumping Duty...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-30

    ... International Trade Administration Citric Acid and Certain Citrate Salts From Canada: Final Results of... of the antidumping duty order on citric acid and certain citrate salts from Canada.\\1\\ The review... period of review (POR) is May 1, 2011, through April 30, 2012. \\1\\ See Citric Acid and Certain...

  11. 78 FR 34648 - Citric Acid and Certain Citrate Salts: Preliminary Results of Countervailing Duty Administrative...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-10

    ... International Trade Administration Citric Acid and Certain Citrate Salts: Preliminary Results of Countervailing... review of the countervailing duty (CVD) order on citric acid and citrate salts from the People's Republic... (202) 482-1503. Scope of the Order The merchandise subject to the order is citric acid and...

  12. 76 FR 34044 - Citric Acid and Certain Citrate Salts From Canada: Final Results of Antidumping Duty...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-10

    ... International Trade Administration Citric Acid and Certain Citrate Salts From Canada: Final Results of... preliminary results of the first administrative review of the antidumping duty order on citric acid and certain citrate salts (citric acid) from Canada. The review covers one manufacturer/exporter of...

  13. 77 FR 22560 - Citric Acid and Certain Citrate Salts From the People's Republic of China: Extension of Time...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-16

    ... International Trade Administration Citric Acid and Certain Citrate Salts From the People's Republic of China... acid and certain citrate salts (``citric acid'') from the People's Republic of China (``PRC'').\\1\\ On...). \\2\\ See Citric Acid and Certain Citrate Salts From the People's Republic of China: Extension of...

  14. 77 FR 9891 - Citric Acid and Certain Citrate Salts from the People's Republic of China: Amended Final Results...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-21

    ... International Trade Administration Citric Acid and Certain Citrate Salts from the People's Republic of China... antidumping duty order on citric acid and certain citrate salts (``citric acid'') from the People's Republic... Act of 1930, as amended (``the Act''). \\1\\ See Citric Acid and Certain Citrate Salts from the...

  15. 76 FR 77772 - Citric Acid and Certain Citrate Salts from the People's Republic of China: Final Results of the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-14

    ... International Trade Administration Citric Acid and Certain Citrate Salts from the People's Republic of China... of the antidumping duty order on citric acid and certain citrate salts (``citric acid'') from the... Citric Acid and Certain Citrate Salts from the People's Republic of China: Preliminary Results of...

  16. 76 FR 33219 - Citric Acid and Certain Citrate Salts from the People's Republic of China: Preliminary Results of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-08

    ... International Trade Administration Citric Acid and Certain Citrate Salts from the People's Republic of China... administrative review of the countervailing duty order on citric acid and certain citrate salts from the People's... countervailing duty order on citric acid and certain citrate salts (``citric acid'') from the People's...

  17. 76 FR 17835 - Citric Acid and Certain Citrate Salts From the People's Republic of China: Extension of Time...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-31

    ... International Trade Administration A-570-937] Citric Acid and Certain Citrate Salts From the People's Republic... order on citric acid and certain citrate salts (``citric acid'') from the People's Republic of China.... See Citric Acid and Certain Citrate Salts from the People's Republic of China: Notice of Extension...

  18. CitI, a Transcription Factor Involved in Regulation of Citrate Metabolism in Lactic Acid Bacteria†

    PubMed Central

    Martin, Mauricio G.; Magni, Christian; de Mendoza, Diego; López, Paloma

    2005-01-01

    A large variety of lactic acid bacteria (LAB) can utilize citrate under fermentative conditions. Although much information concerning the metabolic pathways leading to citrate utilization by LAB has been gathered, the mechanisms regulating these pathways are obscure. In Weissella paramesenteroides (formerly called Leuconostoc paramesenteroides), transcription of the citMDEFCGRP citrate operon and the upstream divergent gene citI is induced by the presence of citrate in the medium. Although genetic experiments have suggested that CitI is a transcriptional activator whose activity can be modulated in response to citrate availability, specific details of the interaction between CitI and DNA remained unknown. In this study, we show that CitI recognizes two A+T-rich operator sites located between citI and citM and that the DNA-binding affinity of CitI is increased by citrate. Subsequently, this citrate signal propagation leads to the activation of the cit operon through an enhanced recruitment of RNA polymerase to its promoters. Our results indicate that the control of CitI by the cellular pools of citrate provides a mechanism for sensing the availability of citrate and adjusting the expression of the cit operon accordingly. In addition, this is the first reported example of a transcription factor directly functioning as a citrate-activated switch allowing the cell to optimize the generation of metabolic energy. PMID:16030208

  19. 77 FR 56188 - Citric Acid and Certain Citrate Salts from the People's Republic of China: Notice of Rescission...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-12

    ... International Trade Administration Citric Acid and Certain Citrate Salts from the People's Republic of China... of the countervailing duty (CVD) order on citric acid and certain citrate salts from the People's...\\ See Citric Acid and Certain Citrate Salts from the People's Republic of China: Intent to...

  20. [Analysis of citric acid and citrates. Citric acid and urolithiasis].

    PubMed

    Leskovar, P

    1979-08-01

    In the first part the physico-chemical, analytic chemical and physiologic biochemical properties of the citric acid are discussed. In the second part the author enters the role of the citric acid in the formation of uric calculi. In the third part is reported on the individual methods of the determination of citric acid and the method practised in the author's laboratory is described.

  1. Comparison of isolation of Haemophilus vaginalis (Corynebacterium vaginale) from peptone-starch-dextrose agar and Columbia colistin-nalidoxic acid agar.

    PubMed Central

    Golberg, R L; Washington JA, I I

    1976-01-01

    A total of 447 cervical or vaginal specimens were inoculated in parallel onto peptone-starch-dextrose (PSD) and Columbia colistin (10 mg/ml)-nalidixic acid (15 mug/ml) (CNA) agar and were incubated for 48 h at 35 degrees C in an atmosphere with 2 to 10% CO2. One hundred (22.4%) of the cultures were positive for Haemophilus vaginalis. Forty-eight of the isolates were recovered from both PSD and Columbia CNA agar, five from PSD only, and 47 from Columbia CNA agar only (P less than 0.001). On Columbia CNA agar, 76 of the isolates were detected after 24 h of incubation, and the remainder were detected within 4 days of incubation. PMID:1085777

  2. Studies in the photogalvanic effect in mixed reductants system for solar energy conversion and storage: Dextrose and Ethylenediaminetetraacetic acid-Azur A system

    SciTech Connect

    Gangotri, K.M.; Indora, Vinod

    2010-02-15

    A mixture of two reductants (Dextrose and ethylenediamine tetraacetic acid) is used as a mixed reductants with Azur A as photosensitizer in the photogalvanic cell for solar energy conversion and storage with the aim to reduce the cost of construction for commercial viability. The photogeneration of photopotential and photocurrent were 778.0 mV and 55.0 {mu}A, respectively, whereas maximum power of the cell was 42.79 {mu}W. The observed power at power point of the cell was 10.87 {mu}W and conversion efficiency was 0.1045%.The determined fill factor was 0.1942. The photogalvanic cell so developed can work for 115.0 min in dark where it was irradiated for 175.0 min. A mechanism for the photogeneration of electricity has also been proposed. (author)

  3. 77 FR 72323 - Citric Acid and Certain Citrate Salts From the People's Republic of China: Final Results of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-05

    ... International Trade Administration Citric Acid and Certain Citrate Salts From the People's Republic of China... certain citrate salts from the People's Republic of China for the period January 1, 2010, through December... Acid and Certain Citrate Salts from the People's Republic of China: Preliminary Results...

  4. 76 FR 82275 - Citric Acid and Certain Citrate Salts From the People's Republic of China: Extension of Time...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-30

    ... International Trade Administration Citric Acid and Certain Citrate Salts From the People's Republic of China... countervailing duty order on citric acid and certain citrate salts from the People's Republic of China (PRC). See... and Certain Citrate Salts, 74 FR 25705 (May 29, 2009). On May 2, 2011, the Department published...

  5. 77 FR 74171 - Citric Acid and Certain Citrate Salts From the People's Republic of China: Final Results of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-13

    ... International Trade Administration Citric Acid and Certain Citrate Salts From the People's Republic of China... certain citrate salts from the People's Republic of China (``PRC'') on June 6, 2012.\\1\\ The period of... Citric Acid and Certain Citrate Salts from the People's Republic of China: Post- Preliminary...

  6. Transport of citrate across renal brush border membrane: effects of dietary acid and alkali loading

    SciTech Connect

    Jenkins, A.D.; Dousa, T.P.; Smith, L.H.

    1985-10-01

    Dietary acid or alkali loading was given to rats by providing 150 mM NH4Cl or 150 mM NaHCO3 in place of drinking water for 6 days; control animals received 150 mM NaCl. After 6 days, the citrate clearance was 0.04 +/- 0.01 ml/min (mean +/- SE) in the acid-loaded group, 0.9 +/- 0.1 ml/min in the control group, and 2.5 +/- 0.2 ml/min in the alkali-loaded group. At the end of the experiment, the rats were killed, and the Na gradient-dependent citrate uptake was measured in brush border membrane (BBM) vesicles prepared from each group. At 0.3 min, the ( UC)citrate uptake was 198 +/- 8 pmol/mg protein (mean +/- SE) in the acid-loaded group, 94 +/- 16 pmol/mg protein in the control group, and 94 +/- 13 pmol/mg protein in the alkali-loaded group. The rate of Na -independent (NaCl in medium replaced by KCl) ( UC)-citrate uptake by BBM vesicles was the same for acid-loaded, control, and alkali-loaded animals. Thus, the increased capacity of the proximal tubular BBM to transport citrate from the tubular lumen into the cell interior may be an important factor that contributes to decreased urinary citrate in the presence of metabolic acidosis induced by chronic dietary acid loading.

  7. Differential modulation of citrate synthesis and release by fatty acids in perfused working rat hearts.

    PubMed

    Vincent, Genevieve; Bouchard, Bertrand; Khairallah, Maya; Des Rosiers, Christine

    2004-01-01

    The objective of this study was to test the effect of increasing fatty acid concentrations on substrate fluxes through pathways leading to citrate synthesis and release in the heart. This was accomplished using semirecirculating work-performing rat hearts perfused with substrate mixtures mimicking the in situ milieu (5.5 mM glucose, 8 nM insulin, 1 mM lactate, 0.2 mM pyruvate, and 0.4 mM oleate-albumin) and 13C methods. Raising the fatty acid concentration from 0.4 to 1 mM with long-chain oleate or medium-chain octanoate resulted in a lowering ( approximately 20%) of cardiac output and efficiency with unaltered O2 consumption. At the metabolic level, beyond the expected effects of high fatty acid levels on the contribution of pyruvate decarboxylation (reduced >3-fold) and beta-oxidation (enhanced approximately 3-fold) to citrate synthesis, there was also a 2.4-fold lowering of anaplerotic pyruvate carboxylation. Despite the dual inhibitory effect of high fatty acids on pyruvate decarboxylation and carboxylation, tissue citrate levels were twofold higher, but citrate release rates remained unchanged at 11-14 nmol/min, representing <0.5% of citric acid cycle flux. A similar trend was observed for most metabolic parameters after oleate or octanoate addition. Together, these results emphasize a differential modulation of anaplerotic pyruvate carboxylation and citrate release in the heart by fatty acids. We interpret the lack of effects of high fatty acid concentrations on citrate release rates as suggesting that, under physiological conditions, this process is maximal, probably limited by the activity of its mitochondrial or plasma membrane transporter. Limited citrate release at high fatty acid concentrations may have important consequences for the heart's fuel metabolism and function.

  8. 77 FR 1455 - Citric Acid and Certain Citrate Salts From the People's Republic of China: Extension of Time...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-10

    ... International Trade Administration Citric Acid and Certain Citrate Salts From the People's Republic of China... acid and certain citrate salts (``citric acid'') from the People's Republic of China (``PRC''). See... of the administrative review of citric acid from the PRC within this time limit....

  9. 76 FR 4288 - Citric Acid and Certain Citrate Salts From the People's Republic of China: Notice of Extension of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-25

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF COMMERCE International Trade Administration Citric Acid and Certain Citrate Salts From the People's Republic of China... review of the antidumping duty order on citric acid and certain citrate salts (``citric acid'') from...

  10. 76 FR 77206 - Citric Acid and Certain Citrate Salts From the People's Republic of China: Final Results of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-12

    ... International Trade Administration Citric Acid and Certain Citrate Salts From the People's Republic of China...'') has completed its administrative review of the countervailing duty (``CVD'') order on citric acid and... Citric Acid and Certain Citrate Salts from the People's Republic of China: Preliminary Results...

  11. 76 FR 49735 - Citric Acid and Certain Citrate Salts From the People's Republic of China: Partial Rescission of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-11

    ... International Trade Administration Citric Acid and Certain Citrate Salts From the People's Republic of China... review of the countervailing duty order on citric acid and certain citrate salts (``citric acid'') from..., 2011, Huangshi Xinghua Biochemical Co., Ltd. (``Xinghua''), a producer and exporter of citric...

  12. 77 FR 33167 - Citric Acid and Certain Citrate Salts From the People's Republic of China: Preliminary Results of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-05

    ... International Trade Administration Citric Acid and Certain Citrate Salts From the People's Republic of China... conducting an administrative review of the countervailing duty (CVD) order on citric acid and citrate salts.... SUPPLEMENTARY INFORMATION: Background On May 29, 2009, the Department published a CVD order on citric acid...

  13. 76 FR 47146 - Citric Acid and Certain Citrate Salts From the People's Republic of China: Extension of Time...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-04

    ... International Trade Administration Citric Acid and Certain Citrate Salts From the People's Republic of China...'') published the initiation of the administrative review of the antidumping duty order on citric acid and certain citrate salts (``citric acid'') from the People's Republic of China (``PRC''). See Initiation...

  14. 78 FR 34642 - Citric Acid and Certain Citrate Salts From the People's Republic of China: Preliminary Results of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-10

    ... International Trade Administration Citric Acid and Certain Citrate Salts From the People's Republic of China... Department'') is conducting an administrative review of the antidumping duty order on citric acid and certain citrate salts (``citric acid'') from the People's Republic of China (``PRC''). The period of review...

  15. Parenteral amino acids v. dextrose infusion: an anabolic strategy to minimise the catabolic response to surgery while maintaining normoglycaemia in diabetes mellitus type 2 patients.

    PubMed

    Lugli, Andrea Kopp; Donatelli, Francesco; Schricker, Thomas; Kindler, Christoph H; Wykes, Linda; Carli, Franco

    2012-02-01

    Loss of body protein and hyperglycaemia represent typical features of the stress response to surgery and anaesthesia. This appears to be particularly pronounced in patients with diabetes mellitus type 2. The aim of the present study was to highlight the greater benefit of amino acids (AA) as represented by positive protein balance and maintenance of blood glucose homoeostasis compared with dextrose (DEX) in diabetic patients after colorectal surgery. A total of thirteen patients underwent a 5 h stable isotope infusion study (2 h fasted, 3 h fed with an infusion of AA (n 6) or DEX (n 7)) on the second post-operative day. Glucose and protein kinetics were assessed by using the stable isotopes l-[1-¹³C]leucine and [6,6-²H₂]glucose. The transition from fasted to fed state decreased endogenous glucose production (P < 0·001) in both groups, with a more profound effect in the DEX group (P = 0·031). In contrast, total glucose production was increased by the provision of DEX while being lowered by AA (P = 0·021). Feeding decreased protein oxidation (P = 0·009) and protein synthesis in the AA group, whereas DEX infusion did not affect oxidation and even decreased protein synthesis. Therefore, only AA shifted protein balance to a positive value, while patients in the DEX group remained in a catabolic state (P < 0·001). Parenteral nutritional support with AA rather than with DEX is an effective strategy to achieve a positive protein balance while maintaining normoglycaemia in diabetic patients after colorectal surgery.

  16. 78 FR 54625 - Citric Acid and Certain Citrate Salts From the People's Republic of China: Notice of Partial...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-05

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF COMMERCE International Trade Administration Citric Acid and Certain Citrate Salts From the People's Republic of China... citric acid and certain citrate salts from the People's Republic of China (PRC) covering the period...

  17. 76 FR 2648 - Citric Acid and Certain Citrate Salts From People's Republic of China: Extension of Time Limit...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-14

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF COMMERCE International Trade Administration Citric Acid and Certain Citrate Salts From People's Republic of China... initiation of administrative review of the countervailing duty order on citric acid and certain citrate...

  18. 76 FR 34048 - Citric Acid and Certain Citrate Salts From the People's Republic of China: Preliminary Results of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-10

    ..., which are intermediate products in the production of citric acid, sodium citrate, and potassium citrate... factors of production (``FOP''), valued in a surrogate market-economy (``ME'') country or countries... respondents' factors of production.\\8\\ On November 17, 2010, Yixing Union identified both Indonesia and...

  19. Enhanced citric acid biosynthesis in Pseudomonas fluorescens ATCC 13525 by overexpression of the Escherichia coli citrate synthase gene.

    PubMed

    Buch, Aditi D; Archana, G; Kumar, G Naresh

    2009-08-01

    Citric acid secretion by fluorescent pseudomonads has a distinct significance in microbial phosphate solubilization. The role of citrate synthase in citric acid biosynthesis and glucose catabolism in pseudomonads was investigated by overexpressing the Escherichia coli citrate synthase (gltA) gene in Pseudomonas fluorescens ATCC 13525. The resultant approximately 2-fold increase in citrate synthase activity in the gltA-overexpressing strain Pf(pAB7) enhanced the intracellular and extracellular citric acid yields during the stationary phase, by about 2- and 26-fold, respectively, as compared to the control, without affecting the growth rate, glucose depletion rate or biomass yield. Decreased glucose consumption was paralleled by increased gluconic acid production due to an increase in glucose dehydrogenase activity. While the extracellular acetic acid yield increased in Pf(pAB7), pyruvic acid secretion decreased, correlating with an increase in pyruvate carboxylase activity and suggesting an increased demand for the anabolic precursor oxaloacetate. Activities of two other key enzymes, glucose-6-phosphate dehydrogenase and isocitrate dehydrogenase, remained unaltered, and the contribution of phosphoenolpyruvate carboxylase and isocitrate lyase to glucose catabolism was negligible. Strain Pf(pAB7) demonstrated an enhanced phosphate-solubilizing ability compared to the control. Co-expression of the Synechococcus elongatus PCC 6301 phosphoenolpyruvate carboxylase and E. coli gltA genes in P. fluorescens ATCC 13525, so as to supplement oxaloacetate for citrate biosynthesis, neither significantly affected citrate biosynthesis nor caused any change in the other physiological and biochemical parameters measured, despite approximately 1.3- and 5-fold increases in citrate synthase and phosphoenolpyruvate carboxylase activities, respectively. Thus, our results demonstrate that citrate synthase is rate-limiting in enhancing citrate biosynthesis in P. fluorescens ATCC 13525

  20. The interaction of phenolic acids with Fe(III) in the presence of citrate as studied by isothermal titration calorimetry.

    PubMed

    Yang, Senpei; Bai, Guangling; Chen, Lingli; Shen, Qun; Diao, Xianmin; Zhao, Guanghua

    2014-08-15

    Under physiological conditions, exogenous chelators such as polyphenols might interact with non-protein bound ferric complexes, such as Fe(III)-citrate. Additionally, Fe(III) and citrate are widely distributed in various fruits and vegetables which are also rich in phenolic acids. In this study, we focus on the interaction between phenolic acids (gallic acid, methyl gallate and protocatechuic acid) and Fe(III) in the presence of excessive citrate by isothermal titration calorimetry (ITC) for thermodynamic studies, and stopped-flow absorption spectrometry for fast kinetic studies. Results reveal that all of these three phenolic acids can bind to the Fe(III) with the same stoichiometry (3:1). Moreover, the binding constants of these three compounds with Fe(III) are greatly dependent on ligand structure, and are much higher than that of Fe(III)-citrate. Based on their stoichiometry and superhigh binding constants, it is most likely that these three phenolic acids can displace the citrate to bind with one iron(III) ion to form a stable octahedral geometric structure, albeit at different rates. These findings shed light on the interaction between phenolic acids and Fe(III) in the presence of citrate under either physiological conditions or in a food system.

  1. Properties of Aspergillus niger citrate synthase and effects of citA overexpression on citric acid production.

    PubMed

    Ruijter, G J; Panneman, H; Xu, D; Visser, J

    2000-03-01

    Using a combination of dye adsorption and affinity elution we purified Aspergillus niger citrate synthase to homogeneity using a single column and characterised the enzyme. An A. niger citrate synthase cDNA was isolated by immunological screening and used to clone the corresponding citA gene. The deduced amino acid sequence showed high similarity to other fungal citrate synthases. After processing upon mitochondrial import, the calculated M(r) of A. niger citrate synthase is 48501, which agrees well with the estimated molecular mass of the purified protein (48 kDa). In addition to an N-terminal mitochondrial import signal, a peroxisomal target sequence (AKL) was found at the C-terminus of the protein. Whether both signals are functional in vivo is not clear. Strains overexpressing citA were made by transformation and cultured under citric acid-producing conditions. Up to 11-fold overproduction of citrate synthase did not increase the rate of citric acid production by the fungus, suggesting that citrate synthase contributes little to flux control in the pathway involved in citric acid biosynthesis by a non-commercial strain.

  2. Exogenous γ-aminobutyric acid treatment affects citrate and amino acid accumulation to improve fruit quality and storage performance of postharvest citrus fruit.

    PubMed

    Sheng, Ling; Shen, Dandan; Luo, Yi; Sun, Xiaohua; Wang, Jinqiu; Luo, Tao; Zeng, Yunliu; Xu, Juan; Deng, Xiuxin; Cheng, Yunjiang

    2017-02-01

    The loss of organic acids during postharvest storage is one of the major factors that reduces the fruit quality and economic value of citrus. Citrate is the most important organic acid in citrus fruits. Molecular evidence has proved that γ-aminobutyric acid (GABA) shunt plays a key role in citrate metabolism. Here, we investigated the effects of exogenous GABA treatment on citrate metabolism and storage quality of postharvest citrus fruit. The content of citrate was significantly increased, which was primarily attributed to the inhibition of the expression of glutamate decarboxylase (GAD). Amino acids, including glutamate, alanine, serine, aspartate and proline, were also increased. Moreover, GABA treatment decreased the fruit rot rate. The activities of antioxidant enzymes and the content of energy source ATP were affected by the treatment. Our results indicate that GABA treatment is a very effective approach for postharvest quality maintenance and improvement of storage performance in citrus production.

  3. Comparison of bismuth citrate and 5-aminosalicylic acid enemas in distal ulcerative colitis: a controlled trial.

    PubMed Central

    Pullan, R D; Ganesh, S; Mani, V; Morris, J; Evans, B K; Williams, G T; Rhodes, J

    1993-01-01

    An enema that contained a complex of bismuth citrate and polyacrylate was compared with 5-aminosalicylic acid (5-ASA) enemas for treatment of distal ulcerative colitis. The multicentre trial involving 63 patients was randomised and double blind with enemas given over four weeks; clinical, sigmoidoscopic, and histological assessments were made. Improvements were seen in both treatment groups. Clinical remission was seen in 18 of 32 patients treated with 5-ASA and 12 of 31 patients treated with bismuth citrate-carbomer (chi 2 1.94; p = 0.16). Sigmoidoscopic remission occurred in 20 of 32 patients in the 5-ASA group and 15 of 31 patients given bismuth (chi 2 1.27; p = 0.26). Improvement of rectal biopsy histology by at least one grade was seen in 16 of 32 patients in the 5-ASA group and 14 of 31 patients with bismuth (chi 2 0.15; p = 0.70). Analysis of covariance gave no significant difference between groups, although there was a trend favouring 5-ASA. There was no evidence of bismuth accumulation during the trial. Bismuth enemas may offer a new therapeutic option in distal ulcerative colitis. PMID:8504970

  4. Influence of concentration, time and method of application of citric acid and sodium citrate in root conditioning

    PubMed Central

    CAVASSIM, Rodrigo; LEITE, Fábio Renato Manzolli; ZANDIM, Daniela Leal; DANTAS, Andrea Abi Rached; RACHED, Ricardo Samih Georges Abi; SAMPAIO, José Eduardo Cezar

    2012-01-01

    Objective The aim of this study was to establish the parameters of concentration, time and mode of application of citric acid and sodium citrate in relation to root conditioning. Material and Methods A total of 495 samples were obtained and equally distributed among 11 groups (5 for testing different concentrations of citric acid, 5 for testing different concentrations of sodium citrate and 1 control group). After laboratorial processing, the samples were analyzed under scanning electron microscopy. A previously calibrated and blind examiner evaluated micrographs of the samples. Non-parametric statistical analysis was performed to analyze the data obtained. Results Brushing 25% citric acid for 3 min, promoted greater exposure of collagen fibers in comparison with the brushing of 1% citric acid for 1 minute and its topical application at 1% for 3 min. Sodium citrate exposed collagen fibers in a few number of samples. Conclusion Despite the lack of statistical significance, better results for collagen exposure were obtained with brushing application of 25% citric acid for 3 min than with other application parameter. Sodium citrate produced a few number of samples with collagen exposure, so it is not indicated for root conditioning. PMID:22858707

  5. 76 FR 56158 - Citric Acid and Certain Citrate Salts From the People's Republic of China: Extension of Time...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-12

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF COMMERCE International Trade Administration Citric Acid and Certain Citrate Salts From the People's Republic of China: Extension of Time Limit for the Final Results of the Countervailing Duty Administrative Review...

  6. Low-temperature Storage of Cucumbers Induces Changes in the Organic Acid Content and in Citrate Synthase Activity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To elucidate the cause of reported pyruvate accumulation in chilled stored cucumbers (Cucumis sativus L.) cv. ‘Toppugurin’, we have examined differences in the extent of incorporation of acetate-1,2-14C into the tricarboxylic acid (TCA) cycle and the specific activity of the enzyme citrate synthase ...

  7. Ferrous iron oxidation by molecular oxygen under acidic conditions: The effect of citrate, EDTA and fulvic acid

    NASA Astrophysics Data System (ADS)

    Jones, Adele M.; Griffin, Philippa J.; Waite, T. David

    2015-07-01

    In this study, the rates of Fe(II) oxidation by molecular oxygen in the presence of citrate, ethylenediaminetetraacetic acid (EDTA) and Suwannee River fulvic acid (SRFA) were determined over the pH range 4.0-5.5 and, for all of the ligands investigated, found to be substantially faster than oxidation rates in the absence of any ligand. EDTA was found to be particularly effective in enhancing the rate of Fe(II) oxidation when sufficient EDTA was available to complex all Fe(II) present in solution, with a kinetic model of the process found to adequately describe all results obtained. When Fe(II) was only partially complexed by EDTA, reactions with reactive oxygen species (ROS) and heterogeneous Fe(II) oxidation were found to contribute significantly to the removal rate of iron from solution at different stages of oxidation. This was possible due to the rapid rate at which EDTA enhanced Fe(II) oxidation and formed ROS and Fe(III). The rapid rate of Fe(III) generation facilitated the formation of free ferric ion activities in excess of those required for ferric oxyhydroxide precipitation following Fe(III)-EDTA dissociation. In comparison, the rate of Fe(II) oxidation was slower in the presence of citrate, and therefore the concentrations of free Fe(III) able to form in the initial stages of Fe(II) oxidation were much lower than those formed in the presence of EDTA, despite the resultant Fe(III)-citrate complex being less stable than that of Fe(III)-EDTA. The slower rate of citrate enhanced oxidation also resulted in slower rates of ROS generation, and, as such, oxidation of the remaining inorganic Fe(II) species by ROS was negligible. Overall, this study demonstrates that organic ligands may substantially enhance the rate of Fe(II) oxidation. Even under circumstances where the ligand is not present at sufficient concentrations to complex all of the Fe(II) in solution, ensuing oxidative processes may sustain an enhanced rate of Fe(II) oxidation relative to that of

  8. Probing the origin of acetyl-CoA and oxaloacetate entering the citric acid cycle from the 13C labeling of citrate released by perfused rat hearts.

    PubMed

    Comte, B; Vincent, G; Bouchard, B; Des Rosiers, C

    1997-10-17

    We present a strategy for simultaneous assessment of the relative contributions of anaplerotic pyruvate carboxylation, pyruvate decarboxylation, and fatty acid oxidation to citrate formation in the perfused rat heart. This requires perfusing with a mix of 13C-substrates and determining the 13C labeling pattern of a single metabolite, citrate, by gas chromatography-mass spectrometry. The mass isotopomer distributions of the oxaloacetate and acetyl moieties of citrate allow calculation of the flux ratios: (pyruvate carboxylation)/(pyruvate decarboxylation), (pyruvate carboxylation)/(citrate synthesis), (pyruvate decarboxylation)/(citrate synthesis) (pyruvate carboxylation)/(fatty acid oxidation), and (pyruvate decarboxylation)/(fatty acid oxidation). Calculations, based on precursor-product relationship, are independent of pool size. The utility of our method was demonstrated for hearts perfused under normoxia with [U-13C3](lactate + pyruvate) and [1-13C]octanoate under steady-state conditions. Under these conditions, effluent and tissue citrate were similarly enriched in all 13C mass isotopomers. The use of effluent citrate instead of tissue citrate allows probing substrate fluxes through the various reactions non-invasively in the intact heart. The methodology should also be applicable to hearts perfused with other 13C-substrates, such as 1-13C-labeled long chain fatty acid, and under various conditions, provided that assumptions on which equations are developed are valid.

  9. Vascular effects of intravenous intralipid and dextrose infusions in obese subjects.

    PubMed

    Gosmanov, Aidar R; Smiley, Dawn D; Peng, Limin; Siquiera, Joselita; Robalino, Gonzalo; Newton, Christopher; Umpierrez, Guillermo E

    2012-10-01

    Hyperglycemia and elevated free fatty acids (FFA) are implicated in the development of endothelial dysfunction. Infusion of soy-bean oil-based lipid emulsion (Intralipid®) increases FFA levels and results in elevation of blood pressure (BP) and endothelial dysfunction in obese healthy subjects. The effects of combined hyperglycemia and high FFA on BP, endothelial function and carbohydrate metabolism are not known. Twelve obese healthy subjects received four random, 8-h IV infusions of saline, Intralipid 40 mL/h, Dextrose 10% 40 mL/h, or combined Intralipid and dextrose. Plasma levels of FFA increased by 1.03±0.34 mmol/L (p=0.009) after Intralipid, but FFAs remained unchanged during saline, dextrose, and combined Intralipid and dextrose infusion. Plasma glucose and insulin concentrations significantly increased after dextrose and combined Intralipid and dextrose (all, p<0.05) and were not different from baseline during saline and lipid infusion. Intralipid increased systolic BP by 12±9 mmHg (p<0.001) and diastolic BP by 5±6 mmHg (p=0.022),and decreased flow-mediated dilatation (FMD) from baseline by 3.2%±1.4% (p<0.001). Saline and dextrose infusion had neutral effects on BP and FMD. The co-administration of lipid and dextrose decreased FMD by 2.4%±2.1% (p=0.002) from baseline, but did not significantly increase systolic or diastolic BP. Short-term Intralipid infusion significantly increased FFA and BP; in contrast, FFA and BP were unchanged during combined infusion of Intralipid and dextrose. Combined Intralipid and dextrose infusion resulted in endothelial dysfunction similar to Intralipid alone.

  10. Prevention of valproic acid-induced neural tube defects by sildenafil citrate.

    PubMed

    Tiboni, Gian Mario; Ponzano, Adalisa

    2015-08-15

    This study was undertaken to test the effects of sildenafil citrate (SC), a type 5 phosphodiesterase inhibitor, on valproic acid (VPA)-induced teratogenesis. On gestation day (GD) 8, ICR (CD-1) mice were treated by gastric intubation with SC at 0 (vehicle), 1.0, 2.5, 5.0 or 10mg/kg. One hour later, animals received a teratogenic dose of VPA (600mg/kg) or vehicle. Developmental endpoints were evaluated near the end of gestation. Twenty-eighth percent of fetuses exposed to VPA had neural tube defects (exencephaly). Pretreatment with SC at 2.5, 5.0 or 10mg/kg significantly reduced the rate of VPA-induced exencephaly to 15.9%, 13.7%, and 10.0%, respectively. Axial skeletal defects were observed in 75.8% of VPA-exposed fetuses. Pre-treatment with SC at 10mg/kg, but not at lower doses, significantly decreased the rate of skeletally affected fetuses to 61.6%. These results show that SC, which prolongs nitric oxide (NO) signaling action protects from VPA-induced teratogenesis.

  11. Nutritional and Hormonal Regulation of Citrate and Carnitine/Acylcarnitine Transporters: Two Mitochondrial Carriers Involved in Fatty Acid Metabolism

    PubMed Central

    Giudetti, Anna M.; Stanca, Eleonora; Siculella, Luisa; Gnoni, Gabriele V.; Damiano, Fabrizio

    2016-01-01

    The transport of solutes across the inner mitochondrial membrane is catalyzed by a family of nuclear-encoded membrane-embedded proteins called mitochondrial carriers (MCs). The citrate carrier (CiC) and the carnitine/acylcarnitine transporter (CACT) are two members of the MCs family involved in fatty acid metabolism. By conveying acetyl-coenzyme A, in the form of citrate, from the mitochondria to the cytosol, CiC contributes to fatty acid and cholesterol synthesis; CACT allows fatty acid oxidation, transporting cytosolic fatty acids, in the form of acylcarnitines, into the mitochondrial matrix. Fatty acid synthesis and oxidation are inversely regulated so that when fatty acid synthesis is activated, the catabolism of fatty acids is turned-off. Malonyl-CoA, produced by acetyl-coenzyme A carboxylase, a key enzyme of cytosolic fatty acid synthesis, represents a regulator of both metabolic pathways. CiC and CACT activity and expression are regulated by different nutritional and hormonal conditions. Defects in the corresponding genes have been directly linked to various human diseases. This review will assess the current understanding of CiC and CACT regulation; underlining their roles in physio-pathological conditions. Emphasis will be placed on the molecular basis of the regulation of CiC and CACT associated with fatty acid metabolism. PMID:27231907

  12. 21 CFR 168.110 - Dextrose anhydrous.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Dextrose anhydrous. 168.110 Section 168.110 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION SWEETENERS AND TABLE SIRUPS Requirements for Specific Standardized Sweeteners...

  13. 21 CFR 168.111 - Dextrose monohydrate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Dextrose monohydrate. 168.111 Section 168.111 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION SWEETENERS AND TABLE SIRUPS Requirements for Specific Standardized Sweeteners...

  14. 21 CFR 168.110 - Dextrose anhydrous.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Dextrose anhydrous. 168.110 Section 168.110 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION SWEETENERS AND TABLE SIRUPS Requirements for Specific Standardized Sweeteners...

  15. 21 CFR 168.111 - Dextrose monohydrate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 2 2013-04-01 2013-04-01 false Dextrose monohydrate. 168.111 Section 168.111 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION SWEETENERS AND TABLE SIRUPS Requirements for Specific Standardized Sweeteners...

  16. 21 CFR 168.110 - Dextrose anhydrous.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Dextrose anhydrous. 168.110 Section 168.110 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION SWEETENERS AND TABLE SIRUPS Requirements for Specific Standardized Sweeteners...

  17. 21 CFR 168.111 - Dextrose monohydrate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Dextrose monohydrate. 168.111 Section 168.111 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION SWEETENERS AND TABLE SIRUPS Requirements for Specific Standardized Sweeteners...

  18. 21 CFR 168.110 - Dextrose anhydrous.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Dextrose anhydrous. 168.110 Section 168.110 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION SWEETENERS AND TABLE SIRUPS Requirements for Specific Standardized Sweeteners...

  19. 21 CFR 168.110 - Dextrose anhydrous.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 2 2013-04-01 2013-04-01 false Dextrose anhydrous. 168.110 Section 168.110 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION SWEETENERS AND TABLE SIRUPS Requirements for Specific Standardized Sweeteners...

  20. D-Amino acid oxidase-induced oxidative stress, 3-bromopyruvate and citrate inhibit angiogenesis, exhibiting potent anticancer effects.

    PubMed

    El Sayed, S M; El-Magd, R M Abou; Shishido, Y; Yorita, K; Chung, S P; Tran, D H; Sakai, T; Watanabe, H; Kagami, S; Fukui, K

    2012-10-01

    Angiogenesis is critical for cancer growth and metastasis. Steps of angiogenesis are energy consuming, while vascular endothelial cells are highly glycolytic. Glioblastoma multiforme (GBM) is a highly vascular tumor and this enhances its aggressiveness. D-amino acid oxidase (DAO) is a promising therapeutic protein that induces oxidative stress upon acting on its substrates. Oxidative stress-energy depletion (OSED) therapy was recently reported (El Sayed et al., Cancer Gene Ther, 19, 1-18, 2012). OSED combines DAO-induced oxidative stress with energy depletion caused by glycolytic inhibitors such as 3-bromopyruvate (3BP), a hexokinase II inhibitor that depleted ATP in cancer cells and induced production of hydrogen peroxide. 3BP disturbs the Warburg effect and antagonizes effects of lactate and pyruvate (El Sayed et al., J Bioenerg Biomembr, 44, 61-79, 2012). Citrate is a natural organic acid capable of inhibiting glycolysis by targeting phosphofructokinase. Here, we report that DAO, 3BP and citrate significantly inhibited angiogenesis, decreased the number of vascular branching points and shortened the length of vascular tubules. OSED delayed the growth of C6/DAO glioma cells. 3BP combined with citrate delayed the growth of C6 glioma cells and decreased significantly the number and size of C6 glioma colonies in soft agar. Human GBM cells (U373MG) were resistant to chemotherapy e.g. cisplatin and cytosine arabinoside, while 3BP was effective in decreasing the viability and disturbing the morphology of U373MG cells.

  1. Enhancement of L-lactic acid production in Lactobacillus casei from Jerusalem artichoke tubers by kinetic optimization and citrate metabolism.

    PubMed

    Ge, Xiang-Yang; Qian, He; Zhang, Wei-Guo

    2010-01-01

    Efficient L-lactic acid production from Jerusalem artichoke tubers by Lactobacillus casei G-02 using simultaneous saccharification and fermentation (SSF) in fed-batch culture is demonstrated. The kinetic analysis in the SSF signified that the inulinase activity was subjected to product inhibition, while the fermentation activity of G-02 was subjected to substrate inhibition. It was also found that the intracellularly NOX activity was enhanced by the citrate metabolism, which increased the carbon flux of Embden-Meyerhof-Parnas (EMP) pathway dramatically, and resulted more ATP production. As a result, when the SSF was carried out at 40 degrees after the initial hydrolysis of 1 h with supplemented sodium citrate of 10g/L, L-lactic acid concentration of 141.5 g/L was obtained in 30 h with a volumetric productivity of 4.7 g/L/h. The conversion efficiency and product yield were 93.6% of the theoretical lactic acid yield and 52.4 g lactic acid/100 g Jerusalem artichoke flour, respectively. Such a high concentration of lactic acid with high productivity from Jerusalem artichoke has not been reported previously, and hence G-02 could be a potential candidate for economical production of L-lactic acid from Jerusalem artichoke at a commercial scale.

  2. Effect of bismuth citrate, lactose, and organic acid on necrotic enteritis in broilers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Clostridium perfringens – associated necrotic enteritis causes significant losses and increased morbidity in poultry. The objective of this study was to evaluate the effect of bismuth citrate and acidifiers on the development of necrotic enteritis in broilers. The first study was a dose response t...

  3. 21 CFR 184.1298 - Ferric citrate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... Substances Affirmed as GRAS § 184.1298 Ferric citrate. (a) Ferric citrate (iron (III) citrate, C6H5FeO7, CAS Reg. No. 2338-05-8) is prepared from reaction of citric acid with ferric hydroxide. It is a compound of indefinite ratio of citric acid and iron. (b) The ingredient must be of a purity suitable for...

  4. 21 CFR 184.1298 - Ferric citrate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Substances Affirmed as GRAS § 184.1298 Ferric citrate. (a) Ferric citrate (iron (III) citrate, C6H5FeO7, CAS Reg. No. 2338-05-8) is prepared from reaction of citric acid with ferric hydroxide. It is a compound of indefinite ratio of citric acid and iron. (b) The ingredient must be of a purity suitable for...

  5. Phenotypes of gene disruptants in relation to a putative mitochondrial malate-citrate shuttle protein in citric acid-producing Aspergillus niger.

    PubMed

    Kirimura, Kohtaro; Kobayashi, Keiichi; Ueda, Yuka; Hattori, Takasumi

    2016-09-01

    The mitochondrial citrate transport protein (CTP) functions as a malate-citrate shuttle catalyzing the exchange of citrate plus a proton for malate between mitochondria and cytosol across the inner mitochondrial membrane in higher eukaryotic organisms. In this study, for functional analysis, we cloned the gene encoding putative CTP (ctpA) of citric acid-producing Aspergillus niger WU-2223L. The gene ctpA encodes a polypeptide consisting 296 amino acids conserved active residues required for citrate transport function. Only in early-log phase, the ctpA disruptant DCTPA-1 showed growth delay, and the amount of citric acid produced by strain DCTPA-1 was smaller than that by parental strain WU-2223L. These results indicate that the CTPA affects growth and thereby citric acid metabolism of A. niger changes, especially in early-log phase, but not citric acid-producing period. This is the first report showing that disruption of ctpA causes changes of phenotypes in relation to citric acid production in A. niger.

  6. The Effect on Serum Ionic Magnesium of Exchange Transfusion with Citrated as Opposed to Heparinized Blood

    PubMed Central

    Bajpai, Prakash C.; Denton, Ronald L.; Harpur, Eleanor; Stern, Leo; Sugden, Donald L.

    1967-01-01

    Serum Mg++ levels before, during, and after replacement transfusion were determined in 20 newborn infants. In 10 infants exchanged with acid-citrate-dextrose (ACD) blood, the level fell from 1.75 ± 0.16 mEq./l. to 0.99 ± 0.16 mEq./l. By contrast, levels in 10 infants exchanged with two types of heparinized blood were unchanged: the pre-exchange values were 1.59 ± 0.11, and the postexchange levels were 1.59 ± 0.08 mEq./l. Mean values for donor bloods were 0.42 ± 0.07 mEq./l. with ACD blood, and 1.45 ± 0.03 mEq./l. with heparinized blood. In vitro studies involving the addition of known amounts of citrate to standard Mg++ solutions demonstrated that the citrate caused a reduction of ionic magnesium. It is proposed that the fall in serum Mg++ when ACD blood is used for exchange transfusion is the combined result of Mg++ binding by the citrate, and the dilution effect of the relatively large proportion of anticoagulant to blood (1:3) used with the ACD mixture. PMID:6066819

  7. In vitro evidence that D-serine disturbs the citric acid cycle through inhibition of citrate synthase activity in rat cerebral cortex.

    PubMed

    Zanatta, Angela; Schuck, Patrícia Fernanda; Viegas, Carolina Maso; Knebel, Lisiane Aurélio; Busanello, Estela Natacha Brandt; Moura, Alana Pimentel; Wajner, Moacir

    2009-11-17

    The present work investigated the in vitro effects of D-serine (D-Ser) on important parameters of energy metabolism in cerebral cortex of young rats. The parameters analyzed were CO(2) generation from glucose and acetate, glucose uptake and the activities of the respiratory chain complexes I-IV, of the citric acid cycle enzymes citrate synthase, aconitase, isocitrate dehydrogenase, alpha-ketoglutarate dehydrogenase, succinate dehydrogenase, fumarase and malate dehydrogenase and of creatine kinase and Na(+),K(+)-ATPase. Our results show that D-Ser significantly reduced CO(2) production from acetate, but not from glucose, reflecting an impairment of the citric acid cycle function. Furthermore, D-Ser did not affect glucose uptake. We also observed that the activity of the mitochondrial enzyme citrate synthase from mitochondrial preparations and purified citrate synthase was significantly inhibited by D-Ser, whereas the other activities of the citric acid cycle as well as the activities of complexes I-III, II-III, II and IV of the respiratory chain, creatine kinase and Na(+),K(+)-ATPase were not affected by this D-amino acid. We also found that L-serine did not affect citrate synthase activity from mitochondrial preparations and purified enzyme. The data indicate that D-Ser impairs the citric acid cycle activity via citrate synthase inhibition, therefore compromising energy metabolism production in cerebral cortex of young rats. Therefore, it is presumed that this mechanism may be involved at least in part in the neurological damage found in patients affected by disorders in which D-Ser metabolism is impaired, with altered cerebral concentrations of this D-amino acid.

  8. 21 CFR 184.1195 - Calcium citrate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... acid with calcium hydroxide or calcium carbonate. It occurs as a fine white, odorless powder and... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Calcium citrate. 184.1195 Section 184.1195 Food... Specific Substances Affirmed as GRAS § 184.1195 Calcium citrate. (a) Calcium citrate...

  9. 21 CFR 184.1195 - Calcium citrate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... acid with calcium hydroxide or calcium carbonate. It occurs as a fine white, odorless powder and... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Calcium citrate. 184.1195 Section 184.1195 Food... Specific Substances Affirmed as GRAS § 184.1195 Calcium citrate. (a) Calcium citrate...

  10. Amino acid-dependent transformations of citrate-coated silver nanoparticles: impact on morphology, stability and toxicity.

    PubMed

    Shi, Junpeng; Sun, Xia; Zou, Xiaoyan; Zhang, Hongwu

    2014-08-17

    Humans face the risk of exposure to silver nanoparticles (AgNPs) due to their extensive application in consumer products. AgNPs can interact with many substances in the human body due to their chemically unstable nature and high activity properties, which might result in unknown hazards and even some serious diseases for humans. As the basic constituent element of human bodies, amino acids (AAs) differ in concentration and variety in different cells and tissues. Thus, understanding the transformation of citrate-coated AgNPs in the presence of AAs is crucial for determining their fate and toxicity in the human body. Our study focused on the transformation of the morphology, dissolution behavior and reaction product of AgNPs in different AA-containing systems and then evaluated the effect of these transformations on the cytotoxicity of AgNPs. The obtained results indicated that the addition of glycine with the lowest Ag(+) binding energy had little effect on the transformations and toxicity of AgNPs. While in the presence of histidine with higher Ag(+) binding energy, the Ag(+) release and particle size of AgNPs obviously increased. These transformations resulted in a decrease in the cytotoxicity of AgNPs due to the formation of Ag-His complex and the growth of AgNPs. Furthermore, l-cysteine with the highest Ag(+) binding energy could easily interact with AgNPs, transforming them completely to form [Ag(Cys)n](+) and Ag2S precipitates, which induced the largest decrease in AgNP toxicity. In summary, our results may provide useful information to understand the fate, transformation, and toxicity of citrate-coated AgNPs in the human body.

  11. Spectrophotometric determination of sildenafil citrate in pure form and in pharmaceutical formulation using some chromotropic acid azo dyes.

    PubMed

    Issa, Y M; El-Hawary, W F; Youssef, A F A; Senosy, A R

    2010-04-01

    Two simple and highly sensitive spectrophotometric methods were developed for the quantitative determination of the drug sildenafil citrate (SC), Viagra, in pure form and in pharmaceutical formulations, through ion-associate formation reactions (method A) with mono-chromotropic acid azo dyes, chromotrope 2B (I) and chromotrope 2R (II) and ion-pair reactions (method B) with bi-chromotropic acid azo dyes, 3-phenylazo-6-o-carboxyphenylazo-chromotropic acid (III), bis-3,6-(o-hydroxyphenylazo)-chromotropic acid (IV), bis-3,6-(p-N,N-dimethylphenylazo)-chromotropic acid (V) and 3-phenylazo-6-o-hydroxyphenylazo-chromotorpic acid (VI). The reaction products, extractable in methylene chloride, were quantitatively measured at 540, 520, 540, 570, 600 and 575 nm using reagents, I-VI, respectively. The reaction conditions were studied and optimized. Beer's plots were linear in the concentration ranges 3.3-87.0, 3.3-96.0, 5.0-115.0, 2.5-125.0, 8.3-166.7 and 0.8-15.0 microg mL(-1) with corresponding molar absorptivities 1.02 x 10(4), 8.34 x 10(3), 6.86 x 10(3), 5.42 x 10(3), 3.35 x 10(3) and 2.32 x 10(4)Lmol(-1) cm(-1) using reagents I-VI, respectively. The limits of detection and Sandell's sensitivities were calculated. The methods were successfully applied to the analysis of commercial tablets (Vigoran) and the recovery study reveals that there is no interference from the common excipients that are present in tablets. Statistical comparison of the results was performed with regard to accuracy and precision using Student's t- and F-tests at 95% confidence level. There is no significant difference between the reported and proposed methods with regard to accuracy and precision.

  12. Spectrophotometric determination of sildenafil citrate in pure form and in pharmaceutical formulation using some chromotropic acid azo dyes

    NASA Astrophysics Data System (ADS)

    Issa, Y. M.; El-Hawary, W. F.; Youssef, A. F. A.; Senosy, A. R.

    2010-04-01

    Two simple and highly sensitive spectrophotometric methods were developed for the quantitative determination of the drug sildenafil citrate (SC), Viagra, in pure form and in pharmaceutical formulations, through ion-associate formation reactions (method A) with mono-chromotropic acid azo dyes, chromotrope 2B (I) and chromotrope 2R (II) and ion-pair reactions (method B) with bi-chromotropic acid azo dyes, 3-phenylazo-6-o-carboxyphenylazo-chromotropic acid (III), bis-3,6-(o-hydroxyphenylazo)-chromotropic acid (IV), bis-3,6-(p-N,N-dimethylphenylazo)-chromotropic acid (V) and 3-phenylazo-6-o-hydroxyphenylazo-chromotorpic acid (VI). The reaction products, extractable in methylene chloride, were quantitatively measured at 540, 520, 540, 570, 600 and 575 nm using reagents, I-VI, respectively. The reaction conditions were studied and optimized. Beer's plots were linear in the concentration ranges 3.3-87.0, 3.3-96.0, 5.0-115.0, 2.5-125.0, 8.3-166.7 and 0.8-15.0 μg mL -1 with corresponding molar absorptivities 1.02 × 10 4, 8.34 × 10 3, 6.86 × 10 3, 5.42 × 10 3, 3.35 × 10 3 and 2.32 × 10 4 L mol -1 cm -1 using reagents I-VI, respectively. The limits of detection and Sandell's sensitivities were calculated. The methods were successfully applied to the analysis of commercial tablets (Vigoran) and the recovery study reveals that there is no interference from the common excipients that are present in tablets. Statistical comparison of the results was performed with regard to accuracy and precision using Student's t- and F-tests at 95% confidence level. There is no significant difference between the reported and proposed methods with regard to accuracy and precision.

  13. Sildenafil citrate treatment enhances amino acid availability in the conceptus and fetal growth in an ovine model of intrauterine growth restriction.

    PubMed

    Satterfield, M Carey; Bazer, Fuller W; Spencer, Thomas E; Wu, Guoyao

    2010-02-01

    Adequate placental blood flow is essential for the optimal delivery of nutrients from mother to fetus for conceptus growth. Restricted fetal development results from pathophysiological and environmental factors that alter utero-placental blood flow, placental function, and, therefore, nutrient availability in the fetus. To test this hypothesis, 0, 75, or 150 mg/d sildenafil citrate (Viagra) was administered subcutaneously from d 28 to 115 of gestation to either nutrient-restricted [50% of NRC requirements) or adequately-fed ewes (100% of NRC requirements). On d 115, maternal, fetal, and placental tissues and fluids were collected. Concentrations of total amino acids and polyamines in uterine venous and arterial sera, amniotic and allantoic fluids, and fetal umbilical venous serum were lower (P < 0.05) in nutrient-restricted ewes than in adequately fed ewes, as were the ratios of total amino acids in fetal umbilical venous serum to uterine arterial serum. Sildenafil citrate dose-dependently increased (P < 0.05) total amino acids and polyamines in amniotic fluid, allantoic fluid, and fetal serum without affecting values in maternal serum. Fetal weight was lower (P < 0.05) in nutrient-restricted ewes on d 115. Sildenafil citrate treatment dose-dependently increased (P < 0.05) fetal weight in both nutrient-restricted and adequately fed ewes. This study supports the hypothesis that long-term sildenafil citrate treatment enhances fetal growth, at least in part, by increasing the availability of amino acids in the conceptus. These findings may lead to the clinical use of sildenafil citrate in human pregnancies suspected to be at risk for intrauterine fetal growth retardation.

  14. The ketogenic diet component decanoic acid increases mitochondrial citrate synthase and complex I activity in neuronal cells.

    PubMed

    Hughes, Sean David; Kanabus, Marta; Anderson, Glenn; Hargreaves, Iain P; Rutherford, Tricia; O'Donnell, Maura; Cross, J Helen; Rahman, Shamima; Eaton, Simon; Heales, Simon J R

    2014-05-01

    The Ketogenic diet (KD) is an effective treatment with regards to treating pharmaco-resistant epilepsy. However, there are difficulties around compliance and tolerability. Consequently, there is a need for refined/simpler formulations that could replicate the efficacy of the KD. One of the proposed hypotheses is that the KD increases cellular mitochondrial content which results in elevation of the seizure threshold. Here, we have focussed on the medium-chain triglyceride form of the diet and the observation that plasma octanoic acid (C8) and decanoic acid (C10) levels are elevated in patients on the medium-chain triglyceride KD. Using a neuronal cell line (SH-SY5Y), we demonstrated that 250-μM C10, but not C8, caused, over a 6-day period, a marked increase in the mitochondrial enzyme, citrate synthase along with complex I activity and catalase activity. Increased mitochondrial number was also indicated by electron microscopy. C10 is a reported peroxisome proliferator activator receptor γ agonist, and the use of a peroxisome proliferator activator receptor γ antagonist was shown to prevent the C10-mediated increase in mitochondrial content and catalase. C10 may mimic the mitochondrial proliferation associated with the KD and raises the possibility that formulations based on this fatty acid could replace a more complex diet. We propose that decanoic acid (C10) results in increased mitochondrial number. Our data suggest that this may occur via the activation of the PPARγ receptor and its target genes involved in mitochondrial biogenesis. This finding could be of significant benefit to epilepsy patients who are currently on a strict ketogenic diet. Evidence that C10 on its own can modulate mitochondrial number raises the possibility that a simplified and less stringent C10-based diet could be developed.

  15. Study of nucleic acid-gold nanorod interactions and detecting nucleic acid hybridization using gold nanorod solutions in the presence of sodium citrate.

    PubMed

    Kanjanawarut, Roejarek; Su, Xiaodi

    2010-09-01

    In this study, the authors report that sodium citrate can aggregate hexadecyl-trimethyl-ammonium ion(+)-coated gold nanorods (AuNRs), and nucleic acids of different charge and structure properties, i.e., single-stranded DNA (ssDNA), double-stranded DNA (dsDNA), single-stranded peptide nucleic acid (PNA), and PNA-DNA complex, can bind to the AuNRs and therefore retard the sodium citrate-induced aggregation to different extents. The discovery that hybridized dsDNA (and the PNA-DNA complex) has a more pronounced protection effect than ssDNA (and PNA) allows the authors to develop a homogeneous phase AuNRs-based UV-visible (UV-vis) spectral assay for detecting specific sequences of oligonucleotides (20 mer) with a single-base-mismatch selectivity and a limit of detection of 5 nM. This assay involves no tedious bioconjugation and on-particle hybridization. The simple "set and test" format allows for a highly efficient hybridization in a homogeneous phase and a rapid display of the results in less than a minute. By measuring the degree of reduction in AuNR aggregation in the presence of different nucleic acid samples, one can assess how different nucleic acids interact with the AuNRs to complement the knowledge of spherical gold nanoparticles. Besides UV-vis characterization, transmission electron microscopy and zeta potential measurements were conduced to provide visual evidence of the particle aggregation and to support the discussion of the assay principle.

  16. 21 CFR 184.1307c - Ferrous citrate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... the reaction of sodium citrate with ferrous sulfate or by direct action of citric acid on iron filings... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Ferrous citrate. 184.1307c Section 184.1307c Food... Specific Substances Affirmed as GRAS § 184.1307c Ferrous citrate. (a) Ferrous citrate (iron (II)...

  17. 21 CFR 184.1307c - Ferrous citrate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... the reaction of sodium citrate with ferrous sulfate or by direct action of citric acid on iron filings... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Ferrous citrate. 184.1307c Section 184.1307c Food... Specific Substances Affirmed as GRAS § 184.1307c Ferrous citrate. (a) Ferrous citrate (iron (II)...

  18. 21 CFR 184.1307c - Ferrous citrate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... the reaction of sodium citrate with ferrous sulfate or by direct action of citric acid on iron filings... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Ferrous citrate. 184.1307c Section 184.1307c Food... Specific Substances Affirmed as GRAS § 184.1307c Ferrous citrate. (a) Ferrous citrate (iron (II)...

  19. 21 CFR 184.1307c - Ferrous citrate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... the reaction of sodium citrate with ferrous sulfate or by direct action of citric acid on iron filings... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ferrous citrate. 184.1307c Section 184.1307c Food... Specific Substances Affirmed as GRAS § 184.1307c Ferrous citrate. (a) Ferrous citrate (iron (II)...

  20. Liver-specific ATP-citrate lyase inhibition by bempedoic acid decreases LDL-C and attenuates atherosclerosis

    PubMed Central

    Pinkosky, Stephen L.; Newton, Roger S.; Day, Emily A.; Ford, Rebecca J.; Lhotak, Sarka; Austin, Richard C.; Birch, Carolyn M.; Smith, Brennan K.; Filippov, Sergey; Groot, Pieter H.E.; Steinberg, Gregory R.; Lalwani, Narendra D.

    2016-01-01

    Despite widespread use of statins to reduce low-density lipoprotein cholesterol (LDL-C) and associated atherosclerotic cardiovascular risk, many patients do not achieve sufficient LDL-C lowering due to muscle-related side effects, indicating novel treatment strategies are required. Bempedoic acid (ETC-1002) is a small molecule intended to lower LDL-C in hypercholesterolemic patients, and has been previously shown to modulate both ATP-citrate lyase (ACL) and AMP-activated protein kinase (AMPK) activity in rodents. However, its mechanism for LDL-C lowering, efficacy in models of atherosclerosis and relevance in humans are unknown. Here we show that ETC-1002 is a prodrug that requires activation by very long-chain acyl-CoA synthetase-1 (ACSVL1) to modulate both targets, and that inhibition of ACL leads to LDL receptor upregulation, decreased LDL-C and attenuation of atherosclerosis, independently of AMPK. Furthermore, we demonstrate that the absence of ACSVL1 in skeletal muscle provides a mechanistic basis for ETC-1002 to potentially avoid the myotoxicity associated with statin therapy. PMID:27892461

  1. Fabrication and characterization of poly(lactic acid)/acetyl tributyl citrate/carbon black as conductive polymer composites.

    PubMed

    Yu, Jiugao; Wang, Ning; Ma, Xiaofei

    2008-03-01

    By using acetyl tributyl citrate (ATBC) as the plasticizer of poly(lactic acid) (PLA) and carbon black (CB) as conductive filler, electrically conductive polymer composites (CPC) with different CB and ATBC contents were prepared. FTIR revealed that the interaction existed between PLA/ATBC matrix and CB filler and ATBC could improve this interaction. The rheology showed that ATBC could obviously decrease the shear viscosity and improve the fluidity of the composites but just the reverse for CB. With the increasing of CB contents, the enforcement effect, storage modulus, and glass-transition temperature increased but the elongation at break decreased. PLA/ATBC/CB composites exhibited the low electrical percolation thresholds of 0.516, 1.20, 2.46, and 2.74 vol % CB at 30, 20, 10, and 0 wt % ATBC. The conductivity of the composite containing 3.98 vol % CB and 30 wt % ATBC reached 1.60 S/cm. Scanning electron microscopy revealed that the addition of ATBC facilitated the dispersion of the CB in the PLA matrix. Water vapor permeability (WVP) showed that, at the same CB contents, the more ATBC contents there were, the less the values of WVP were.

  2. 21 CFR 184.1625 - Potassium citrate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Potassium citrate. 184.1625 Section 184.1625 Food... GRAS § 184.1625 Potassium citrate. (a) Potassium citrate (C6H5K3O7·H2O, CAS Reg. No. 006100-0905-096) is the potassium salt of citric acid. It is prepared by neutralizing citric acid with...

  3. 21 CFR 184.1751 - Sodium citrate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Sodium citrate. 184.1751 Section 184.1751 Food and....1751 Sodium citrate. (a) Sodium citrate (C6H5Na3O7·2H2O, CAS Reg. No. 68-0904-092) is the sodium salt of citric acid. It is prepared by neutralizing citric acid with sodium hydroxide or sodium...

  4. 21 CFR 184.1751 - Sodium citrate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Sodium citrate. 184.1751 Section 184.1751 Food and... Substances Affirmed as GRAS § 184.1751 Sodium citrate. (a) Sodium citrate (C6H5Na3O7·2H2O, CAS Reg. No. 68-0904-092) is the sodium salt of citric acid. It is prepared by neutralizing citric acid with...

  5. 21 CFR 184.1751 - Sodium citrate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Sodium citrate. 184.1751 Section 184.1751 Food and... Substances Affirmed as GRAS § 184.1751 Sodium citrate. (a) Sodium citrate (C6H5Na3O7·2H2O, CAS Reg. No. 68-0904-092) is the sodium salt of citric acid. It is prepared by neutralizing citric acid with...

  6. 21 CFR 184.1751 - Sodium citrate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Sodium citrate. 184.1751 Section 184.1751 Food and... Substances Affirmed as GRAS § 184.1751 Sodium citrate. (a) Sodium citrate (C6H5Na3O7·2H2O, CAS Reg. No. 68-0904-092) is the sodium salt of citric acid. It is prepared by neutralizing citric acid with...

  7. 21 CFR 184.1751 - Sodium citrate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Sodium citrate. 184.1751 Section 184.1751 Food and... Substances Affirmed as GRAS § 184.1751 Sodium citrate. (a) Sodium citrate (C6H5Na3O7·2H2O, CAS Reg. No. 68-0904-092) is the sodium salt of citric acid. It is prepared by neutralizing citric acid with...

  8. Role of combined use of potassium citrate and tamsulosin in the management of uric acid distal ureteral calculi.

    PubMed

    El-Gamal, Osama; El-Bendary, Mohamed; Ragab, Maged; Rasheed, Mohamed

    2012-06-01

    In this article, we investigated the effect of the combined use of tamsulosin and potassium citrate (Uralyt-U(®)) for the treatment of uric acid stones in the distal ureter. The study was designed as a prospective, double blind randomized controlled trial. A total of 191 adult patients with radiolucent distal ureteral calculi were recruited. We included patients with solitary stones ≥5 mm with mild or moderate hydronephrosis and a normal contralateral tract. The patients were randomized into four equal groups (the placebo, tamsulosin, Uralyt-U(®), and the combined treatment groups). The patients were treated for a maximum duration of 4 weeks or until stone expulsion. The stone size in all groups ranged from 5 to 11 mm (7.69 ± 1.7 mm). The total expulsion rate of the stones was significantly lower in the control group (26.1%) compared with that of any of the other three groups (68.8, 58.7, and 84.8% respectively) (P < 0.05). Meanwhile, the difference between the Uralyt-U(®) group and the combined treatment group was also statistically significant (P < 0.05). When we studied the patients with stones >8 mm as a separate subgroup to find the effect of the used drugs on the relatively large stones, we detected that the expulsion rate of these stones was significantly higher in the patients who received the combined treatment in comparison with any of the other three groups (P < 0.05). In conclusion, the use of urinary alkalization with tamsulosin can increase the frequency of spontaneous passage of distal ureteral uric acid stones especially those of 8-11 mm.

  9. 21 CFR 184.1307c - Ferrous citrate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... citrate with ferrous sulfate or by direct action of citric acid on iron filings. (b) The ingredient must... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Ferrous citrate. 184.1307c Section 184.1307c Food... GRAS § 184.1307c Ferrous citrate. (a) Ferrous citrate (iron (II) citrate, (C6H6FeO7), CAS Reg....

  10. Retention Mechanisms of Citric Acid in Ternary Kaolinite-Fe(III)-Citrate Acid Systems Using Fe K-edge EXAFS and L3,2-edge XANES Spectroscopy

    PubMed Central

    Yang, Jianjun; Wang, Jian; Pan, Weinan; Regier, Tom; Hu, Yongfeng; Rumpel, Cornelia; Bolan, Nanthi; Sparks, Donald

    2016-01-01

    Organic carbon (OC) stability in tropical soils is strongly interlinked with multivalent cation interaction and mineral association. Low molecular weight organic acids (LMWOAs) represent the readily biodegradable OC. Therefore, investigating retention mechanisms of LMWOAs in mineral-cation-LMWOAs systems is critical to understanding soil C cycling. Given the general acidic conditions and dominance of kaolinite in tropical soils, we investigated the retention mechanisms of citric acid (CA) in kaolinite-Fe(III)-CA systems with various Fe/CA molar ratios at pH ~3.5 using Fe K-edge EXAFS and L3,2-edge XANES techniques. With Fe/CA molar ratios >2, the formed ferrihydrite mainly contributed to CA retention through adsorption and/or coprecipitation. With Fe/CA molar ratios from 2 to 0.5, ternary complexation of CA to kaolinite via a five-coordinated Fe(III) bridge retained higher CA than ferrihydrite-induced adsorption and/or coprecipitation. With Fe/CA molar ratios ≤0.5, kaolinite-Fe(III)-citrate complexation preferentially occurred, but less CA was retained than via outer-sphere kaolinite-CA complexation. This study highlighted the significant impact of varied Fe/CA molar ratios on CA retention mechanisms in kaolinite-Fe(III)-CA systems under acidic conditions, and clearly showed the important contribution of Fe-bridged ternary complexation on CA retention. These findings will enhance our understanding of the dynamics of CA and other LMWOAs in tropical soils. PMID:27212680

  11. Retention Mechanisms of Citric Acid in Ternary Kaolinite-Fe(III)-Citrate Acid Systems Using Fe K-edge EXAFS and L3,2-edge XANES Spectroscopy

    NASA Astrophysics Data System (ADS)

    Yang, Jianjun; Wang, Jian; Pan, Weinan; Regier, Tom; Hu, Yongfeng; Rumpel, Cornelia; Bolan, Nanthi; Sparks, Donald

    2016-05-01

    Organic carbon (OC) stability in tropical soils is strongly interlinked with multivalent cation interaction and mineral association. Low molecular weight organic acids (LMWOAs) represent the readily biodegradable OC. Therefore, investigating retention mechanisms of LMWOAs in mineral-cation-LMWOAs systems is critical to understanding soil C cycling. Given the general acidic conditions and dominance of kaolinite in tropical soils, we investigated the retention mechanisms of citric acid (CA) in kaolinite-Fe(III)-CA systems with various Fe/CA molar ratios at pH ~3.5 using Fe K-edge EXAFS and L3,2-edge XANES techniques. With Fe/CA molar ratios >2, the formed ferrihydrite mainly contributed to CA retention through adsorption and/or coprecipitation. With Fe/CA molar ratios from 2 to 0.5, ternary complexation of CA to kaolinite via a five-coordinated Fe(III) bridge retained higher CA than ferrihydrite-induced adsorption and/or coprecipitation. With Fe/CA molar ratios ≤0.5, kaolinite-Fe(III)-citrate complexation preferentially occurred, but less CA was retained than via outer-sphere kaolinite-CA complexation. This study highlighted the significant impact of varied Fe/CA molar ratios on CA retention mechanisms in kaolinite-Fe(III)-CA systems under acidic conditions, and clearly showed the important contribution of Fe-bridged ternary complexation on CA retention. These findings will enhance our understanding of the dynamics of CA and other LMWOAs in tropical soils.

  12. Identification of highly concentrated dextrose solution (50% dextrose) extravasation and treatment--a clinical report.

    PubMed

    Lawson, Sarah L; Brady, William; Mahmoud, Ahmed

    2013-05-01

    Treatment for significant hypoglycemia includes administration of dextrose containing agents, including 50% dextrose (D50%W) intravenously. Significant extravasation of D50%W can lead to complications, including skin and soft tissue injury, loss of limb, or death. The aim of this case report, using an interdisciplinary team approach, explores extravasation protocols as well as literature review, is to provide information about the proper use of hyaluronidase in patients with D50%W extravasations. A 46-year-old African American man presented to the emergency department (ED) after blood glucose level was initially 13 mg/dL. Emergency medical service established a large bore intravenous (IV) line in the right antecubital vein and administered a total of 50 g of D50%W. Upon arrival to the ED, the patient's level of consciousness had significantly improved. After arrival to the ED, the patient started complaining of pain in his right arm, near the site of the IV line insertion. On inspection, the IV site was grossly infiltrated. Hospital protocols for hyperosmolar infiltration were used. Extravasation is a common medical complication of infused medications and needs to be properly identified and treated. The multitude of skills from nursing, medicine, and pharmacy ensures that extravasation is managed appropriately and effectively to ensure safety to patients. Recognition, communication, and awareness of the institutional guidelines on how to treat infiltration and extravasation should be encouraged in all ED and intensive care unit medical personnel who deal with a variety of infusions and IV medications that have serious implications if not treated correctly.

  13. Effect of acidity on the citrate-nitrate combustion synthesis of alumina-zirconia composite powder

    NASA Astrophysics Data System (ADS)

    Chandradass, J.; Kim, Ki Hyeon

    2009-12-01

    Alumina-zirconia composite powders were produced by sol-gel autocombustion. 20 wt.% ZrO2-Al2O3 mixture precursor solutions were chelated by citric acid ions at different pH. DTA analysis shows sluggish decomposition at low pH, whereas there was rapid decomposition at high pH = 9. XRD patterns of the calcined powders showed that well crystallized powder with 100 % tetragonal phase and α-alumina phase is produced when pH = 0.58 (without ammonia addition). TEM characterization of composite powders revealed homogenous distribution of nanosized zirconia particles in the alumina matrix. FTIR analysis shows peaks at 590 cm-1 and 454 cm-1, which are identified as the characteristic absorption bands of Zr-O and Al-O.

  14. 21 CFR 184.1386 - Isopropyl citrate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... Specific Substances Affirmed as GRAS § 184.1386 Isopropyl citrate. (a) Isopropyl citrate is a mixture of the mono-, di-, and triisopropyl esters of citric acid. It is prepared by esterifying citric acid with... practice. The affirmation of this ingredient as generally recognized as safe (GRAS) as a direct human...

  15. 21 CFR 184.1851 - Stearyl citrate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Substances Affirmed as GRAS § 184.1851 Stearyl citrate. (a) Stearyl citrate is a mixture of the mono-, di-, and tristearyl esters of citric acid. It is prepared by esterifying citric acid with stearyl alcohol... practice. The affirmation of this ingredient as generally recognized as safe (GRAS) as a direct human...

  16. 21 CFR 184.1386 - Isopropyl citrate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Specific Substances Affirmed as GRAS § 184.1386 Isopropyl citrate. (a) Isopropyl citrate is a mixture of the mono-, di-, and triisopropyl esters of citric acid. It is prepared by esterifying citric acid with... practice. The affirmation of this ingredient as generally recognized as safe (GRAS) as a direct human...

  17. 21 CFR 184.1195 - Calcium citrate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... Specific Substances Affirmed as GRAS § 184.1195 Calcium citrate. (a) Calcium citrate (Ca3(C6H5O7)2·4H2O, CAS Reg. No. 813-0994-095) is the calcium salt of citric acid. It is prepared by neutralizing citric acid with calcium hydroxide or calcium carbonate. It occurs as a fine white, odorless powder...

  18. 21 CFR 184.1851 - Stearyl citrate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... Specific Substances Affirmed as GRAS § 184.1851 Stearyl citrate. (a) Stearyl citrate is a mixture of the mono-, di-, and tristearyl esters of citric acid. It is prepared by esterifying citric acid with... manufacturing practice. The affirmation of this ingredient as generally recognized as safe (GRAS) as a...

  19. 21 CFR 184.1911 - Triethyl citrate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... Specific Substances Affirmed as GRAS § 184.1911 Triethyl citrate. (a) Triethyl citrate (C12H20O7, CAS Reg. No. 77-93-0) is the triethyl ester of citric acid. It is prepared by esterifying citric acid with... recognized as safe (GRAS) as a direct human food ingredient is based upon the following current...

  20. 21 CFR 184.1911 - Triethyl citrate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Specific Substances Affirmed as GRAS § 184.1911 Triethyl citrate. (a) Triethyl citrate (C12H20O7, CAS Reg. No. 77-93-0) is the triethyl ester of citric acid. It is prepared by esterifying citric acid with... recognized as safe (GRAS) as a direct human food ingredient is based upon the following current...

  1. The control of fatty acid and triglyceride synthesis in rat epididymal adipose tissue. Roles of coenzyme A derivatives, citrate and l-glycerol 3-phosphate

    PubMed Central

    Denton, R. M.; Halperin, M. L.

    1968-01-01

    1. Methods are described for the extraction and assay of acetyl-CoA and of total acid-soluble and total acid-insoluble CoA derivatives in rat epididymal adipose tissue. 2. The concentration ranges of the CoA derivatives in fat pads incubated in vitro under various conditions were: total acid-soluble CoA, 0·20–0·59mm; total acid-insoluble CoA, 0·08–0·23mm; acetyl-CoA, 0·03–0·14mm. 3. An investigation was made of some postulated mechanisms of control of fatty acid and triglyceride synthesis in rat epididymal fat pads incubated in vitro. The concentrations of intermediates of possible regulatory significance were measured at various rates of fatty acid and triglyceride synthesis produced by the addition to the incubation medium (Krebs bicarbonate buffer containing glucose) of insulin, adrenaline, albumin, palmitate or acetate. 4. The whole-tissue concentrations of glucose 6-phosphate, l-glycerol 3-phosphate, citrate, acetyl-CoA, total acid-soluble CoA and total acid-insoluble CoA were assayed after 30 or 60min. incubation. The rates of fatty acid and triglyceride synthesis, calculated from the incorporation of [U-14C]glucose into fatty acids and glyceride glycerol respectively, and the rates of glucose uptake, lactate plus pyruvate output and glycerol output were measured over a 60min. incubation. 5. The rate of triglyceride synthesis could not be correlated with the concentrations of either l-glycerol 3-phosphate or long-chain fatty acyl-CoA (measured as total acid-insoluble CoA). Factor(s) other than the whole-tissue concentrations of these recognized precursors appear to be involved in the determination of the rate of triglyceride synthesis. 6. No relationship was found between the rate of fatty acid synthesis and the whole-tissue concentrations of the intermediates, citrate or acetyl-CoA, or with the two proposed effectors of acetyl-CoA carboxylase, citrate (as activator) or long-chain fatty acyl-CoA (as inhibitor). The control of fatty acid synthesis

  2. 21 CFR 184.1625 - Potassium citrate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Potassium citrate. 184.1625 Section 184.1625 Food... Specific Substances Affirmed as GRAS § 184.1625 Potassium citrate. (a) Potassium citrate (C6H5K3O7·H2O, CAS Reg. No. 006100-0905-096) is the potassium salt of citric acid. It is prepared by neutralizing...

  3. 21 CFR 184.1625 - Potassium citrate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Potassium citrate. 184.1625 Section 184.1625 Food... Specific Substances Affirmed as GRAS § 184.1625 Potassium citrate. (a) Potassium citrate (C6H5K3O7·H2O, CAS Reg. No. 006100-0905-096) is the potassium salt of citric acid. It is prepared by neutralizing...

  4. 21 CFR 184.1625 - Potassium citrate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Potassium citrate. 184.1625 Section 184.1625 Food... Specific Substances Affirmed as GRAS § 184.1625 Potassium citrate. (a) Potassium citrate (C6H5K3O7·H2O, CAS Reg. No. 006100-0905-096) is the potassium salt of citric acid. It is prepared by neutralizing...

  5. 21 CFR 184.1625 - Potassium citrate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Potassium citrate. 184.1625 Section 184.1625 Food... Specific Substances Affirmed as GRAS § 184.1625 Potassium citrate. (a) Potassium citrate (C6H5K3O7·H2O, CAS Reg. No. 006100-0905-096) is the potassium salt of citric acid. It is prepared by neutralizing...

  6. 77 FR 33399 - Citric Acid and Certain Citrate Salts From the People's Republic of China: Preliminary Results of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-06

    ... monohydrate, and tricalcium citrate tetrahydrate, which are intermediate products in the production of citric... NME producer's factors of production (``FOP''). In accordance with section 773(c)(4) of the Act, in... Department's Policy Bulletin No. 04.1, regarding, ``Non-Market Economy Surrogate Country Selection...

  7. Back to Acid Soil Fields: The Citrate Transporter SbMATE Is a Major Asset for Sustainable Grain Yield for Sorghum Cultivated on Acid Soils

    PubMed Central

    Carvalho, Geraldo; Schaffert, Robert Eugene; Malosetti, Marcos; Viana, Joao Herbert Moreira; Menezes, Cicero Bezerra; Silva, Lidianne Assis; Guimaraes, Claudia Teixeira; Coelho, Antonio Marcos; Kochian, Leon V.; van Eeuwijk, Fred A.; Magalhaes, Jurandir Vieira

    2015-01-01

    Aluminum (Al) toxicity damages plant roots and limits crop production on acid soils, which comprise up to 50% of the world’s arable lands. A major Al tolerance locus on chromosome 3, AltSB, controls aluminum tolerance in sorghum [Sorghum bicolor (L.) Moench] via SbMATE, an Al-activated plasma membrane transporter that mediates Al exclusion from sensitive regions in the root apex. As is the case with other known Al tolerance genes, SbMATE was cloned based on studies conducted under controlled environmental conditions, in nutrient solution. Therefore, its impact on grain yield on acid soils remains undetermined. To determine the real world impact of SbMATE, multi-trait quantitative trait loci (QTL) mapping in hydroponics, and, in the field, revealed a large-effect QTL colocalized with the Al tolerance locus AltSB, where SbMATE lies, conferring a 0.6 ton ha–1 grain yield increase on acid soils. A second QTL for Al tolerance in hydroponics, where the positive allele was also donated by the Al tolerant parent, SC283, was found on chromosome 9, indicating the presence of distinct Al tolerance genes in the sorghum genome, or genes acting in the SbMATE pathway leading to Al-activated citrate release. There was no yield penalty for AltSB, consistent with the highly localized Al regulated SbMATE expression in the root tip, and Al-dependent transport activity. A female effect of 0.5 ton ha–1 independently demonstrated the effectiveness of AltSB in hybrids. Al tolerance conferred by AltSB is thus an indispensable asset for sorghum production and food security on acid soils, many of which are located in developing countries. PMID:26681519

  8. Back to Acid Soil Fields: The Citrate Transporter SbMATE Is a Major Asset for Sustainable Grain Yield for Sorghum Cultivated on Acid Soils.

    PubMed

    Carvalho, Geraldo; Schaffert, Robert Eugene; Malosetti, Marcos; Viana, Joao Herbert Moreira; Menezes, Cicero Bezerra; Silva, Lidianne Assis; Guimaraes, Claudia Teixeira; Coelho, Antonio Marcos; Kochian, Leon V; van Eeuwijk, Fred A; Magalhaes, Jurandir Vieira

    2015-12-17

    Aluminum (Al) toxicity damages plant roots and limits crop production on acid soils, which comprise up to 50% of the world's arable lands. A major Al tolerance locus on chromosome 3, AltSB, controls aluminum tolerance in sorghum [Sorghum bicolor (L.) Moench] via SbMATE, an Al-activated plasma membrane transporter that mediates Al exclusion from sensitive regions in the root apex. As is the case with other known Al tolerance genes, SbMATE was cloned based on studies conducted under controlled environmental conditions, in nutrient solution. Therefore, its impact on grain yield on acid soils remains undetermined. To determine the real world impact of SbMATE, multi-trait quantitative trait loci (QTL) mapping in hydroponics, and, in the field, revealed a large-effect QTL colocalized with the Al tolerance locus AltSB, where SbMATE lies, conferring a 0.6 ton ha(-1) grain yield increase on acid soils. A second QTL for Al tolerance in hydroponics, where the positive allele was also donated by the Al tolerant parent, SC283, was found on chromosome 9, indicating the presence of distinct Al tolerance genes in the sorghum genome, or genes acting in the SbMATE pathway leading to Al-activated citrate release. There was no yield penalty for AltSB, consistent with the highly localized Al regulated SbMATE expression in the root tip, and Al-dependent transport activity. A female effect of 0.5 ton ha(-1) independently demonstrated the effectiveness of AltSB in hybrids. Al tolerance conferred by AltSB is thus an indispensable asset for sorghum production and food security on acid soils, many of which are located in developing countries.

  9. Retention mechanisms of citric acid in ternary kaolinite-Fe(III)-citrate acid systems using Fe K-edge EXAFS and L3,2-edge XANES spectroscopy

    DOE PAGES

    Yang, Jianjun; Wang, Jian; Pan, Weinan; ...

    2016-05-23

    Organic carbon (OC) stability in tropical soils is strongly interlinked with multivalent cation interaction and mineral association. Low molecular weight organic acids (LMWOAs) represent the readily biodegradable OC. Therefore, investigating retention mechanisms of LMWOAs in mineral-cation-LMWOAs systems is critical to understanding soil C cycling. Given the general acidic conditions and dominance of kaolinite in tropical soils, we investigated the retention mechanisms of citric acid (CA) in kaolinite-Fe(III)-CA systems with various Fe/CA molar ratios at pH ~3.5 using Fe K-edge EXAFS and L-3,2-edge XANES techniques. With Fe/CA molar ratios >2, the formed ferrihydrite mainly contributed to CA retention through adsorption and/ormore » coprecipitation. With Fe/CA molar ratios from 2 to 0.5, ternary complexation of CA to kaolinite via a five-coordinated Fe(III) bridge retained higher CA than ferrihydrite-induced adsorption and/or coprecipitation. With Fe/CA molar ratios ≤ 0.5, kaolinite-Fe(III)-citrate complexation preferentially occurred, but less CA was retained than via outer-sphere kaolinite-CA complexation. This study highlighted the significant impact of varied Fe/CA molar ratios on CA retention mechanisms in kaolinite-Fe(III)-CA systems under acidic conditions, and clearly showed the important contribution of Fe-bridged ternary complexation on CA retention. In conclusion, these findings will enhance our understanding of the dynamics of CA and other LMWOAs in tropical soils.« less

  10. Citrate and renal calculi: an update

    NASA Technical Reports Server (NTRS)

    Pak, C. Y.

    1994-01-01

    Citrate is an inhibitor of the crystallization of stone-forming calcium salts. Hypocitraturia, frequently encountered in patients with nephrolithiasis, is therefore an important risk factor for stone formation. Potassium citrate provides physiological and physicochemical correction and inhibits new stone formation, not only in hypocitraturic calcium nephrolithiasis but also in uric acid nephrolithiasis. Inhibition of stone recurrence has now been validated by a randomized trial. Ongoing research has disclosed additional causes of hypocitraturia (sodium excess, low intestinal alkali absorption, but not primary citrate malabsorption). Moreover, new insights on potassium citrate action have been shown, notably that some of absorbed citrate escapes oxidation and contributes to the citraturic response, that ingestion with a meal does not sacrifice physiological or physicochemical action, that orange juice mimics but does not completely duplicate its actions, that potassium citrate may have a beneficial bone-sparing effect, that it may reduce stone fragments following ESWL, and that danger of aluminum toxicity is not great in subjects with functioning kidneys. Finally, the research on potassium citrate has led to two promising products, calcium citrate as an optimum calcium supplement and potassium-magnesium citrate which may be superior to potassium citrate in the management of stone disease.

  11. Conversion of citrate synthase into citryl-CoA lyase as a result of mutation of the active-site aspartic acid residue to glutamic acid.

    PubMed Central

    Man, W J; Li, Y; O'Connor, C D; Wilton, D C

    1991-01-01

    The active-site aspartic acid residue, Asp-362, of Escherichia coli citrate synthase was changed by site-directed mutagenesis to Glu-362, Asn-362 or Gly-362. Only very low catalytic activity could be detected with the Asp----Asn and Asp----Gly mutations. The Asp----Glu mutation produced an enzyme that expressed about 0.8% of the overall catalytic rate, and the hydrolysis step in the reaction, monitored as citryl-CoA hydrolysis, was inhibited to a similar extent. However, the condensation reaction, measured in the reverse direction as citryl-CoA cleavage to oxaloacetate and acetyl-CoA, was not affected by the mutation, and this citryl-CoA lyase activity was the major catalytic activity of the mutant enzyme. This high condensation activity in an enzyme in which the subsequent hydrolysis step was about 98% inhibited permitted considerable exchange of the methyl protons of acetyl-CoA during catalysis by the mutant enzyme. The Km for oxaloacetate was not significantly altered in the D362E mutant enzyme, whereas the Km for acetyl-CoA was about 5 times lower. A mechanism is proposed in which Asp-362 is involved in the hydrolysis reaction of this enzyme, and not as a base in the deprotonation of acetyl-CoA as recently suggested by others. [Karpusas, Branchaud & Remington (1990) Biochemistry 29, 2213-2219; Alter, Casazza, Zhi, Nemeth, Srere & Evans, (1990) Biochemistry 29, 7557-7563]. PMID:1684105

  12. 21 CFR 520.550 - Dextrose/glycine/electrolyte.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ....550 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.550 Dextrose/glycine... therapy. Oral therapy in these cases is too slow. Animals which cannot drink after initial...

  13. The effect of feeding fermented liquid whey plus dextrose inoculated with specific lactic acid bacteria of pig origin to weanling pigs challenged with Escherichia coli O149:K91:F4.

    PubMed

    Amezcua, M D R; Friendship, R; Dewey, C; Weese, S; de Lange, C F M

    2007-01-01

    The objective of this study was to determine the efficacy of using fermented liquid whey inoculated with specific lactic acid bacteria of pig origin to reduce the severity and progression of postweaning enterotoxigenic Escherichia coli diarrhea in weanling pigs challenged with E. coli O149:K91:F4. Based on two trials, it was determined that feeding inoculated fermented whey in a liquid diet did not affect growth performance or the severity or duration of postweaning diarrhea compared with a conventional dry feed containing an antibiotic. Because this study is one of very few examining the use of liquid feed and co-products inoculated with probiotics to control postweaning E. coli diarrhea, more studies are needed to confirm these results.

  14. A novel leady oxide combined with porous carbon skeleton synthesized from lead citrate precursor recovered from spent lead-acid battery paste

    NASA Astrophysics Data System (ADS)

    Hu, Yuchen; Yang, Jiakuan; Zhang, Wei; Xie, Yanlin; Wang, Junxiong; Yuan, Xiqing; Vasant Kumar, R.; Liang, Sha; Hu, Jingping; Wu, Xu

    2016-02-01

    A novel nanostructured leady oxides comprising porous carbon skeleton has been synthesized by thermal decomposition of lead citrate precursor, recovered from spent lead-acid battery paste. The influences of O2 percentage in the calcination atmosphere (O2/N2 mixture) and the temperature on leady oxide product characteristics are studied by chemical analysis, scanning electron microscopy (SEM) and X-ray diffraction (XRD). The major crystalline phases of the products are identified as lead oxides, metallic Pb, and carbon. Porous carbon is observed as skeletons within the leady oxide (PbO containing some Pb metal) particles. Mass percentage of Pb metal in the leady oxide increases with increasing the proportion of oxygen in the calcination atmosphere. However, the amount of carbon decreases from approximately 8.0 to 0.3 wt%, and the porous carbon skeleton structure is gradually damaged with oxygen concentration increasing. A model about the thermal decomposition of lead citrate precursor is firstly proposed to elucidate these observations. The nanostructured leady oxides combined with porous carbon can be directly used as precursor of active materials in a new lead acid battery.

  15. PRODUCTION OF UNIFORMLY SIZED SERUM ALBUMIN AND DEXTROSE MICROBUBBLES

    PubMed Central

    Borrelli, Michael J.; O’Brien, William D.; Bernock, Laura J.; Williams, Heather R.; Hamilton, Eric; Wu, Jonah; Oelze, Michael L.; Culp, William C.

    2011-01-01

    Uniformly-sized preparations with average microbubble (MB) diameters from 1 µm to 7 µm were produced reliably by sonicating decafluorobutane-saturated solutions of serum albumin and dextrose. Detailed protocols for producing and size-separating the MBs are presented, along with the effects that changing each production parameter (serum albumin concentration, sonication power, sonication time, etc.) had on MB size distribution and acoustic stability. These protocols can be used to produce MBs for experimental applications or serve as templates for developing new protocols that yield MBs with physical and acoustic properties better suited to specific applications. Size stability and ultrasonic performance quality control tests were developed to assure that successive MB preparations perform identically and to distinguish the physical and acoustic properties of identically sized MBs produced with different serum albumin-dextrose formulations and sonication parameters. MBs can be stored at 5°C for protracted periods (2 weeks to one year depending on formulation). PMID:21689961

  16. Hydrogen profiles of dobutamine hydrochloride and fentanyl citrate solutions according to intravenous administration systems, temperature, and luminosity conditions.

    PubMed

    Barros, Daniele Porto; Fonseca, Fernando Luiz Affonso; Pedreira, Mavilde da Luz Gonçalves; Peterlini, Maria Angélica Sorgini

    2014-01-01

    Factors such as temperature, light exposure, drug concentration, ionic strength, time of infusion, and duration of drug association can influence the effectiveness of pharmacological solutions, which can compromise the solutions' quality, resulting in unstable solutions and drug incompatibility. The aim of this study was to determine the pH of solutions of dobutamine hydrochloride, fentanyl citrate, and their combination in 5% dextrose in water (D5W) under various light exposures and temperature conditions over time. The analysis was performed by measuring the pH of the substances in both pharmacological (commercial) preparations and in D5W under dark fluorescent light in the presence or absence of sunlight exposures, intravenous apparatus packaging (clear and amber burettes), and temperature (22°C and 37°C). Samples were collected immediately after preparation and after 0.5, 1, 2, 3, 4, and 24 hours of exposure to the various conditions; data were analyzed using mean standard deviations. Of the 260 pH values obtained, 50 (19.2%) were from commercial preparations and 210 (80.8%) from solutions exposed to various experimental conditions. Significant pH differences were found among the vials of the commercial preparation drugs. The largest pH value difference (0.88) was observed for fentanyl citrate, in which a pH increase of 0.88 (4.23 ± 0.62) was observed. The combination of drugs in D5W resulted in more acidic values than those of fentanyl citrate and of D5W and fentanyl citrate in D5W, but they were closer to what was observed for the solution of dobutamine hydrochloride in D5W. This solution was more acidic than fentanyl citrate diluted in D5W. The lower acidity of fentanyl citrate had a minor influence on the final pH of the combined drug solution in D5W. Under most conditions, the drug solutions kept at 22°C had pH values that were more acidic and less variable. Temperature was a major factor controlling the chemical behavior of the solutions analyzed

  17. Assessing the survival of MRC5 and a549 cell lines upon exposure to pyruvic Acid, sodium citrate and sodium bicarbonate - biomed 2013.

    PubMed

    Farah, Ibrahim O; Lewis, Veshell L; Ayensu, Wellington K; Cameron, Joseph A

    2013-01-01

    Lung cancer is among the most prevalent and deadly cancers in United States. In general, cancer cells are known to exhibit higher rates of glycolysis in comparison to normal cells. In attempting to exploit this unique cancer-dependent ATP generation phenomenon, it was our hypothesis that upon exposure to organic inhibitors of glycolysis, cancer cells would not survive normally and that their growth and viability would be vastly decreased; essential glycolytic ATP production will be exhausted to the point of collapsing energy utilization. Furthermore, we hypothesize that no negative effect would be seen with exposures to organic inhibitors for normal lung cells. The human lung fibroblast MRC-5 and the human A549 alveolar epithelial cell lines were used as in vitro models of normal lung and lung cancers respectively. Using standard methods, both cell lines were maintained and exposed to pyruvic acid, sodium citrate and sodium bicarbonate reagents at concentration levels ranging from 31.3-2,000 µg/ml in 96 well plates in quadruplets and experiments repeated at least three times using MTT, and cell counting (T4 Cellometer) assays as well as phase-contrast photo-imaging for parallel morphological displays of any changes in the course of their vitality and metabolic activities. Our results indicate that exposure of both cell lines to these organics resulted in concentration dependent cell destruction/cell survival depending on the cell line exposed. Pyruvic acid, sodium citrate and sodium bicarbonate showed statistically significant (p<0.05) differential negative effects on the A549 cell line in comparison to its unexposed control as well as to their effects on the MRC-5 cell line, presenting a potential promise for their use as cancer biotherapeutics.

  18. Effects of citrate and NaCl on size, morphology, crystallinity and microstructure of calcium phosphates obtained from aqueous solutions at acidic or near-neutral pH.

    PubMed

    Mekmene, Omar; Rouillon, Thierry; Quillard, Sophie; Pilet, Paul; Bouler, Jean-Michel; Pezennec, Stéphane; Gaucheron, Frédéric

    2012-05-01

    Precipitation of calcium phosphates occurs in dairy products and depending on pH and ionic environment, several salts with different crystallinity can form. The present study aimed to investigate the effects of NaCl and citrate on the characteristics of precipitates obtained from model solutions of calcium phosphate at pH 6·70 maintained constant or left to drift. The ion speciation calculations showed that all the starting solutions were supersaturated with respect to dicalcium phosphate dihydrate (DCPD), octacalcium phosphate (OCP) and hydroxyapatite (HAP) in the order HAP>OCP>DCPD. X-ray diffraction (XRD) and Fourier transform infrared (FTIR) analyses of the precipitates showed that DCPD was formed at drifting pH (acidic final pH) whereas poor crystallised calcium deficient apatite was mainly formed at constant pH (6·70). Laser light scattering measurements and electron microscopy observations showed that citrate had a pronounced inhibitory effect on the crystallisation of calcium phosphates both at drifting and constant pH. This resulted in the decrease of the particle sizes and the modification of the morphology and the microstructure of the precipitates. The inhibitory effect of citrate mainly acted by the adsorption of the citrate molecules onto the surfaces of newly formed nuclei of calcium phosphate, thereby changing the morphology of the growing particles. These findings are relevant for the understanding of calcium phosphate precipitation from dairy byproducts that contain large amounts of NaCl and citrate.

  19. Physicochemical action of potassium-magnesium citrate in nephrolithiasis

    NASA Technical Reports Server (NTRS)

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

    1992-01-01

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

  20. A Systematic Review of Dextrose Prolotherapy for Chronic Musculoskeletal Pain

    PubMed Central

    Hauser, Ross A.; Lackner, Johanna B.; Steilen-Matias, Danielle; Harris, David K.

    2016-01-01

    OBJECTIVE The aim of this study was to systematically review dextrose (d-glucose) prolotherapy efficacy in the treatment of chronic musculoskeletal pain. DATA SOURCES Electronic databases PubMed, Healthline, OmniMedicalSearch, Medscape, and EMBASE were searched from 1990 to January 2016. STUDY SELECTION Prospectively designed studies that used dextrose as the sole active prolotherapy constituent were selected. DATA EXTRACTION Two independent reviewers rated studies for quality of evidence using the Physiotherapy Evidence Database assessment scale for randomized controlled trials (RCTs) and the Downs and Black evaluation tool for non-RCTs, for level of evidence using a modified Sackett scale, and for clinically relevant pain score difference using minimal clinically important change criteria. Study population, methods, and results data were extracted and tabulated. DATA SYNTHESIS Fourteen RCTs, 1 case–control study, and 18 case series studies met the inclusion criteria and were evaluated. Pain conditions were clustered into tendinopathies, osteoarthritis (OA), spinal/pelvic, and myofascial pain. The RCTs were high-quality Level 1 evidence (Physiotherapy Evidence Database ≥8) and found dextrose injection superior to controls in Osgood–Schlatter disease, lateral epicondylitis of the elbow, traumatic rotator cuff injury, knee OA, finger OA, and myofascial pain; in biomechanical but not subjective measures in temporal mandibular joint; and comparable in a short-term RCT but superior in a long-term RCT in low back pain. Many observational studies were of high quality and reported consistent positive evidence in multiple studies of tendinopathies, knee OA, sacroiliac pain, and iliac crest pain that received RCT confirmation in separate studies. Eighteen studies combined patient self-rating (subjective) with psychometric, imaging, and/or biomechanical (objective) outcome measurement and found both positive subjective and objective outcomes in 16 studies and positive

  1. 75 FR 71078 - Citric Acid and Certain Citrate Salts From People's Republic of China: Partial Rescission of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-22

    ...., Ltd. Juxian Hongde Citric Acid Co., Ltd. Kelong International Co., Ltd. Laiwu Taihe Biochemistry Co.... Shandong Laiwu Gangcheng Group Shandong Ningmeng Biochemistry Co., Ltd. Shandong Yingfeng Chemical...

  2. 21 CFR 184.1140 - Ammonium citrate, dibasic.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Listing of Specific Substances Affirmed as GRAS § 184.1140 Ammonium citrate, dibasic. (a) Ammonium citrate, dibasic ((NH4)2HC6H5O7, CAS Reg. No. 3012-65-5) is the diammonium salt of citric acid. It is prepared by partially neutralizing citric acid with ammonia. (b) The ingredient must be of a purity suitable for...

  3. 21 CFR 184.1140 - Ammonium citrate, dibasic.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... Listing of Specific Substances Affirmed as GRAS § 184.1140 Ammonium citrate, dibasic. (a) Ammonium citrate, dibasic ((NH4)2HC6H5O7, CAS Reg. No. 3012-65-5) is the diammonium salt of citric acid. It is prepared by partially neutralizing citric acid with ammonia. (b) The ingredient must be of a purity suitable for...

  4. Solid-phase extraction of galloyl- and caffeoylquinic acids from natural sources (Galphimia glauca and Arnicae flos) using pure zirconium silicate and bismuth citrate powders as sorbents inside micro spin columns.

    PubMed

    Hussain, Shah; Schönbichler, Stefan A; Güzel, Yüksel; Sonderegger, Harald; Abel, Gudrun; Rainer, Matthias; Huck, Christian W; Bonn, Günther K

    2013-10-01

    Galloyl- and caffeoylquinic acids are among the most important pharmacological active groups of natural compounds. This study describes a pre-step in isolation of some selected representatives of these groups from biological samples. A selective solid-phase extraction (SPE) method for these compounds may help assign classes and isomer designations within complex mixtures. Pure zirconium silicate and bismuth citrate powders (325 mesh) were employed as two new sorbents for optimized SPE of phenolic acids. These sorbents possess electrostatic interaction sites which accounts for additional interactions for carbon acid moieties as compared to hydrophilic and hydrophobic sorbents alone. Based on this principle, a selective SPE method for 1,3,4,5-tetragalloylquinic acid (an anti-HIV and anti-asthamatic agent) as a starting compound was developed and then deployed upon other phenolic acids with success. The recoveries and selectivities of both sorbents were compared to most commonly applied and commercially available sorbents by using high performance liquid chromatography. The nature of interaction between the carrier sorbent and the acidic target molecules was investigated by studying hydrophilic (silica), hydrophobic (C18), mixed-mode (ionic and hydrophobic: Oasis(®) MAX) and predominantly electrostatic (zirconium silicate) materials. The newly developed zirconium silicate and bismuth citrate stationary phases revealed promising results for the selective extraction of galloyl- and caffeoylquinic acids from natural sources. It was observed that zirconium silicate exhibited maximum recovery and selectivity for tetragalloylquinic acid (84%), chlorogenic acid (82%) and dicaffeoylquinic acid (94%) among all the tested sorbents.

  5. Citrate modulates lipopolysaccharide-induced monocyte inflammatory responses

    PubMed Central

    Ashbrook, M J; McDonough, K L; Pituch, J J; Christopherson, P L; Cornell, T T; Selewski, D T; Shanley, T P; Blatt, N B

    2015-01-01

    Citrate, a central component of cellular metabolism, is a widely used anti-coagulant due to its ability to chelate calcium. Adenosine triphosphate (ATP)-citrate lyase, which metabolizes citrate, has been shown to be essential for inflammation, but the ability of exogenous citrate to impact inflammatory signalling cascades remains largely unknown. We hypothesized that citrate would modulate inflammatory responses as both a cellular metabolite and calcium chelator, and tested this hypothesis by determining how clinically relevant levels of citrate modulate monocyte proinflammatory responses to lipopolysaccharide (LPS) in a human acute monocytic leukaemia cell line (THP-1). In normal medium (0·4 mM calcium), citrate inhibited LPS-induced tumour necrosis factor (TNF)-α and interleukin (IL)-8 transcripts, whereas in medium supplemented with calcium (1·4 mM), TNF-α and IL-8 levels increased and appeared independent of calcium chelation. Using an IL-8–luciferase plasmid construct, the same increased response was observed in the activation of the IL-8 promoter region, suggesting transcriptional regulation. Tricarballylic acid, an inhibitor of ATP-citrate lyase, blocked the ability of citrate to augment TNF-α, linking citrate's augmentation effect with its metabolism by ATP-citrate lyase. In the presence of citrate, increased histone acetylation was observed in the TNF-α and IL-8 promoter regions of THP-1 cells. We observed that citrate can both augment and inhibit proinflammatory cytokine production via modulation of inflammatory gene transactivation. These findings suggest that citrate anti-coagulation may alter immune function through complex interactions with the inflammatory response. PMID:25619261

  6. Analysis of ATP-citrate lyase and malic enzyme mutants of Yarrowia lipolytica points out the importance of mannitol metabolism in fatty acid synthesis.

    PubMed

    Dulermo, Thierry; Lazar, Zbigniew; Dulermo, Rémi; Rakicka, Magdalena; Haddouche, Ramedane; Nicaud, Jean-Marc

    2015-09-01

    The role of the two key enzymes of fatty acid (FA) synthesis, ATP-citrate lyase (Acl) and malic enzyme (Mae), was analyzed in the oleaginous yeast Yarrowia lipolytica. In most oleaginous yeasts, Acl and Mae are proposed to provide, respectively, acetyl-CoA and NADPH for FA synthesis. Acl was mainly studied at the biochemical level but no strain depleted for this enzyme was analyzed in oleaginous microorganisms. On the other hand the role of Mae in FA synthesis in Y. lipolytica remains unclear since it was proposed to be a mitochondrial NAD(H)-dependent enzyme and not a cytosolic NADP(H)-dependent enzyme. In this study, we analyzed for the first time strains inactivated for corresponding genes. Inactivation of ACL1 decreases FA synthesis by 60 to 80%, confirming its essential role in FA synthesis in Y. lipolytica. Conversely, inactivation of MAE1 has no effects on FA synthesis, except in a FA overaccumulating strain where it improves FA synthesis by 35%. This result definitively excludes Mae as a major key enzyme for FA synthesis in Y. lipolytica. During the analysis of both mutants, we observed a negative correlation between FA and mannitol level. As mannitol and FA pathways may compete for carbon storage, we inactivated YlSDR, encoding a mannitol dehydrogenase converting fructose and NADPH into mannitol and NADP+. The FA content of the resulting mutant was improved by 60% during growth on fructose, demonstrating that mannitol metabolism may modulate FA synthesis in Y. lipolytica.

  7. The Safety and Tolerability of 5-Aminolevulinic Acid Phosphate with Sodium Ferrous Citrate in Patients with Type 2 Diabetes Mellitus in Bahrain

    PubMed Central

    Al-Saber, Feryal; Aldosari, Waleed; Alselaiti, Mariam; Khalfan, Hesham; Kaladari, Ahmed; Khan, Ghulam; Harb, George; Rehani, Riyadh; Kudo, Sizuka; Koda, Aya; Tanaka, Tohru

    2016-01-01

    Type 2 diabetes mellitus is prevalent especially in Gulf countries and poses serious long-term risks to patients. A multifaceted treatment approach can include nutritional supplements with antioxidant properties such as 5-aminolevulinic acid (5-ALA) with sodium ferrous citrate (SFC). This prospective, randomized, single-blind, placebo-controlled, dose escalating pilot clinical trial assessed the safety of 5-ALA with SFC at doses up to 200 mg 5-ALA/229.42 mg SFC per day in patients living in Bahrain with type 2 diabetes mellitus that was uncontrolled despite the use of one or more antidiabetic drugs. Fifty-three patients (n = 53) from 3 sites at one center were enrolled by Dr. Feryal (Site #01), Dr. Hesham (Site #02), and Dr. Waleed (Site #03) (n = 35, 5-ALA-SFC; n = 18, placebo). There was no significant difference in incidence of adverse events reported, and the most frequent events reported were gastrointestinal in nature, consistent with the known safety profile of 5-ALA in patients with diabetes. No significant changes in laboratory values and no difference in hypoglycemia between patients receiving 5-ALA and placebo were noted. Overall, the current results support that use of 5-ALA-SFC up to 200 mg per day taken as 2 divided doses is safe in patients taking concomitant oral antidiabetic medications and may offer benefits in the diabetic population. This trial is registered with ClinicalTrials.gov NCT02481141. PMID:27738640

  8. INTRAPERITONEAL DEXTROSE ADMINISTRATION AS AN ALTERNATIVE EMERGENCY TREATMENT FOR HYPOGLYCEMIC YEARLING CALIFORNIA SEA LIONS (ZALOPHUS CALIFORNIANUS).

    PubMed

    Fravel, Vanessa A; Van Bonn, William; Gulland, Frances; Rios, Carlos; Fahlman, Andreas; Graham, James L; Havel, Peter J

    2016-03-01

    The Marine Mammal Center (TMMC) cares for malnourished California sea lion (CSL) (Zalophus californianus) pups and yearlings every year. Hypoglycemia is a common consequence of malnutrition in young CSLs. Administering dextrose during a hypoglycemic crisis is vital to recovery. Traditional veterinary approaches to treat hypoglycemia pose therapeutic challenges in otariids, as vascular access and catheter maintenance can be difficult. The current approach to a hypoglycemic episode at TMMC is to administer dextrose intravenously (i.v.) by medically trained personnel. Intraperitoneal (i.p.) dextrose administration is an attractive alternative to i.v. administration because volunteer staff with basic training can administer treatment instead of waiting for trained staff to treat. This study compares the effects of i.v., i.p., and no dextrose administration on serum glucose and insulin in clinically healthy, euglycemic CSL yearlings. Three groups of animals, consisting of five sea lions each, were treated with 500 mg/kg dextrose using one of the following routes: i.v., i.p., or no dextrose (control). A jugular catheter was placed, and blood samples were collected at times 0, 5, 15, 30, 60, 120, 180, and 240 min after dextrose administration. I.v. dextrose administration resulted in an increase of serum glucose concentrations from a baseline level of approximately 150 mg/dl to a peak of approximately 350 mg/dl. The resulting hyperglycemia persisted for approximately 2 hr and was associated with an attenuated plasma insulin response compared with most terrestrial mammals. Intraperitoneal dextrose administration resulted in increases of serum glucose to approximately 200 mg/dl, which gradually declined to baseline by 2 hr after dextrose administration. These data suggest that the initial treatment of a hypoglycemic crisis in young malnourished CSLs can be accomplished with i.p. dextrose, thus enabling minimally trained volunteer staff to respond immediately to a crisis

  9. Gastrointestinal citrate absorption in nephrolithiasis

    NASA Technical Reports Server (NTRS)

    Fegan, J.; Khan, R.; Poindexter, J.; Pak, C. Y.

    1992-01-01

    Gastrointestinal absorption of citrate was measured in stone patients with idiopathic hypocitraturia to determine if citrate malabsorption could account for low urinary citrate. Citrate absorption was measured directly from recovery of orally administered potassium citrate (40 mEq.) in the intestinal lavage fluid, using an intestinal washout technique. In 7 stone patients citrate absorption, serum citrate levels, peak citrate concentration in serum and area under the curve were not significantly different from those of 7 normal subjects. Citrate absorption was rapid and efficient in both groups, with 96 to 98% absorbed within 3 hours. The absorption of citrate was less efficient from a tablet preparation of potassium citrate than from a liquid preparation, probably due to a delayed release of citrate from wax matrix. However, citrate absorption from solid potassium citrate was still high at 91%, compared to 98% for a liquid preparation. Thus, hypocitraturia is unlikely to be due to an impaired gastrointestinal absorption of citrate in stone patients without overt bowel disease.

  10. 21 CFR 172.370 - Iron-choline citrate complex.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Iron-choline citrate complex. 172.370 Section 172... CONSUMPTION Special Dietary and Nutritional Additives § 172.370 Iron-choline citrate complex. Iron-choline... citric acid may be safely used as a source of iron in foods for special dietary use....

  11. 21 CFR 172.370 - Iron-choline citrate complex.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Iron-choline citrate complex. 172.370 Section 172... CONSUMPTION Special Dietary and Nutritional Additives § 172.370 Iron-choline citrate complex. Iron-choline... citric acid may be safely used as a source of iron in foods for special dietary use....

  12. 21 CFR 172.370 - Iron-choline citrate complex.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Iron-choline citrate complex. 172.370 Section 172... CONSUMPTION Special Dietary and Nutritional Additives § 172.370 Iron-choline citrate complex. Iron-choline... citric acid may be safely used as a source of iron in foods for special dietary use....

  13. 21 CFR 172.370 - Iron-choline citrate complex.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Iron-choline citrate complex. 172.370 Section 172... CONSUMPTION Special Dietary and Nutritional Additives § 172.370 Iron-choline citrate complex. Iron-choline... citric acid may be safely used as a source of iron in foods for special dietary use....

  14. Evaluation of two dextrose-based directly compressible excipients.

    PubMed

    Olmo, I G; Ghaly, E S

    1998-08-01

    The objectives of this research were to evaluate the physical properties and compaction behavior of two dextrose-based directly compressed excipients. Anhydrous theophylline (10% w/w) was used as a drug model, Emdex and or Maltrin M510 (89.5% w/w) were used as diluent, and magnesium stearate (0.5% w/w) was used as lubricant. Direct compression and wet granulation methods were used for preparing the compacts. In general, the wet granulation method reduced the density of the mixture and consequently its flow rate compared to the mixture prepared only by solid-solid mixing. All formulations were compressed at four different compressional forces and at a target weight of 450 mg +/- 5%. Tablets obtained were different in physical properties and mechanical strength based on type of excipient used and methods of tablet preparation (direct compression versus wet granulation). Compacts prepared from Maltrin M510 had a longer disintegration time and slower drug release than compacts of the same composition but prepared with Emdex. Disintegration time and drug dissolution from tablets containing Maltrin M510 as diluent and prepared by wet granulation appeared to be controlled by a "gel" layer formation around the tablets and not by the tablets porosity. This study demonstrates that full characterization of excipients is needed because a different manufacturing process for the same excipients may produce differences in the pharmaceutical products.

  15. Final report on the safety assessment of acetyl triethyl citrate, acetyl tributyl citrate, acetyl trihexyl citrate, and acetyl trioctyl citrate.

    PubMed

    Johnson, Wilbur

    2002-01-01

    Acetyl Triethyl Citrate, Acetyl Tributyl Citrate, Acetyl Trihexyl Citrate, and Acetyl Trioctyl Citrate all function as plasticizers in cosmetics. Additionally, the Trihexyl and Trioctyl forms are described as skin-conditioning agents-emollients, although there are currently no reported uses of Acetyl Trihexyl Citrate or Acetyl Trioctyl Citrate. Acetyl Triethyl Citrate and Acetyl Tributyl Citrate are used in nail products at concentrations up to 7%. Recognizing that there are no reported uses of Acetyl Trihexyl or Trioctyl Citrate, if they were to be used in the future, their concentration of use is expected to be no higher than that reported for Acetyl Triethyl and Tributyl Citrate. These ingredients were sufficiently similar in structure that safety test data on one were considered applicable to all. Approximately 99% of orally administered Acetyl Tributyl Citrate is excreted-intermediate metabolites include acetyl citrate, monobutyl citrate, acetyl monobutyl citrate, dibutyl citrate, and acetyl dibutyl citrate. In acute, short-term, subchronic, and chronic feeding studies, these ingredients were relatively nontoxic. Differences from controls were either not statistically significant or not related to any organ toxicity. Ocular exposures produced moderate reactions that cleared by 48 hours after instillation. Dermal application was not toxic in rabbits. In a guinea pig maximization test, Acetyl Triethyl Citrate was a sensitizer whereas Acetyl Tributyl Citrate was not. Limited clinical testing of Acetyl Triethyl Citrate and Acetyl Tributyl Citrate was negative for both skin irritation and sensitization. These clinical data were considered more relevant than the guinea pig maximization data, suggesting to the Cosmetic Ingredient Review Expert Panel that none of these ingredients would be a sensitizer. Physiologic effects noted with intravenous delivery of Acetyl Triethyl Citrate or Acetyl Tributyl Citrate include dose-related decreases in blood pressure and

  16. Citrate as a siderophore in Bradyrhizobium japonicum.

    PubMed Central

    Guerinot, M L; Meidl, E J; Plessner, O

    1990-01-01

    Under iron-limiting conditions, many bacteria secrete ferric iron-specific ligands, generically termed siderophores, to aid in the sequestering and transport of iron. One strain of the nitrogen-fixing soybean symbiont Bradyrhizobium japonicum, 61A152, was shown to produce a siderophore when 20 B. japonicum strains were screened with all six chemical assays commonly used to detect such production. Production by strain 61A152 was detected via the chrome azurol S assay, a general test for siderophores which is independent of siderophore structure. The iron-chelating compound was neither a catechol nor a hydroxamate and was ninhydrin negative. It was determined to be citric acid via a combination of thin-layer chromatography and high-voltage paper electrophoresis; this identification was verified by a specific enzymatic assay for citric acid. The inverse correlation which was observed between citric acid release and the iron content of the medium suggested that ferric citrate could serve as an iron source. This was confirmed via growth and transport assays. Exogenously added ferric citrate could be used to overcome iron starvation, and iron-deficient cells actively transported radiolabeled ferric citrate. These results, taken together, indicate a role for ferric citrate in the iron nutrition of this strain, which has been shown to be an efficient nitrogen-fixing strain on a variety of soybean cultivars. PMID:2140566

  17. Citrate Metabolism by Pediococcus halophilus

    PubMed Central

    Kanbe, Chiyuki; Uchida, Kinji

    1987-01-01

    Several strains of non-citrate-metabolizing Pediococcus halophilus have previously been isolated from soy sauce mash or moromi. The factors controlling the metabolism of citrate in soy pediococci were studied. All the soy pediococcal strains tested which failed to decompose citrate did not possess citrate lyase [citrate (pro-3S)-lyase; EC 4.1.3.6] activity. In P. halophilus, citrate lyase was an inducible enzyme, and the optimum pH for activity was 7.0. The metabolism of citrate in P. halophilus was different from that observed in lactic streptococci. The main products from citrate were acetate and formate, and this bacterium produced no acetoin or diacetyl. Formate production from citrate was greatly reduced in the presence of glucose. P. halophilus 7117 (Cit+) was proved to contain citrate lyase, pyruvate formate-lyase (EC 2.3.1.54) phosphotransacetylase (phosphate acetyltransferase; EC 2.3.1.8), and acetate kinase (EC 2.7.2.1), i.e., all the enzymes necessary to convert citrate to acetate and formate. PMID:16347358

  18. Synthesis and Antimicrobial Activity of Silver Citrate Complexes

    PubMed Central

    Djokić, Stojan

    2008-01-01

    Formation of silver citrate/citric acid complexed solutions was investigated. Although, silver citrate is minimally soluble in water, it can successfully be dissolved in citric acid solutions. The maximum concentration of Ag(I) in solution is estimated at 23 to 25 g/L if the concentration of citric acid is at least 4 mol/L or higher. The dissolution of silver citrate in citric acid solutions was attributed to the formation of silver citrate complexes of a general formula [Ag3(C6H5O7)n+1]3n−. The silver citrate/citric acid solutions, containing more than about 13 g/L Ag+ ion, have exhibited a decrease in Ag(I) concentration in solution over time, due to crystallization. The crystallization product was attributed to the formation of [Ag3C6H5O7]x·nH2O. Importantly, the diluted silver citrate/citric acid complexed solutions have exhibited very strong bacteriostatic and bactericidal activities. PMID:19079586

  19. Retention mechanisms of citric acid in ternary kaolinite-Fe(III)-citrate acid systems using Fe K-edge EXAFS and L3,2-edge XANES spectroscopy

    SciTech Connect

    Yang, Jianjun; Wang, Jian; Pan, Weinan; Regier, Tom; Hu, Yongfeng; Rumpel, Cornelia; Bolan, Nanthi; Sparks, Donald

    2016-05-23

    Organic carbon (OC) stability in tropical soils is strongly interlinked with multivalent cation interaction and mineral association. Low molecular weight organic acids (LMWOAs) represent the readily biodegradable OC. Therefore, investigating retention mechanisms of LMWOAs in mineral-cation-LMWOAs systems is critical to understanding soil C cycling. Given the general acidic conditions and dominance of kaolinite in tropical soils, we investigated the retention mechanisms of citric acid (CA) in kaolinite-Fe(III)-CA systems with various Fe/CA molar ratios at pH ~3.5 using Fe K-edge EXAFS and L-3,2-edge XANES techniques. With Fe/CA molar ratios >2, the formed ferrihydrite mainly contributed to CA retention through adsorption and/or coprecipitation. With Fe/CA molar ratios from 2 to 0.5, ternary complexation of CA to kaolinite via a five-coordinated Fe(III) bridge retained higher CA than ferrihydrite-induced adsorption and/or coprecipitation. With Fe/CA molar ratios ≤ 0.5, kaolinite-Fe(III)-citrate complexation preferentially occurred, but less CA was retained than via outer-sphere kaolinite-CA complexation. This study highlighted the significant impact of varied Fe/CA molar ratios on CA retention mechanisms in kaolinite-Fe(III)-CA systems under acidic conditions, and clearly showed the important contribution of Fe-bridged ternary complexation on CA retention. In conclusion, these findings will enhance our understanding of the dynamics of CA and other LMWOAs in tropical soils.

  20. Artificial citrate operon and Vitreoscilla hemoglobin gene enhanced mineral phosphate solubilizing ability of Enterobacter hormaechei DHRSS.

    PubMed

    Yadav, Kavita; Kumar, Chanchal; Archana, G; Kumar, G Naresh

    2014-10-01

    Mineral phosphate solubilization by bacteria is mediated through secretion of organic acids, among which citrate is one of the most effective. To overproduce citrate in bacterial systems, an artificial citrate operon comprising of genes encoding NADH-insensitive citrate synthase of E. coli and Salmonella typhimurium sodium-dependent citrate transporter was constructed. In order to improve its mineral phosphate solubilizing (MPS) ability, the citrate operon was incorporated into E. hormaechei DHRSS. The artificial citrate operon transformant secreted 7.2 mM citric acid whereas in the native strain, it was undetectable. The transformant released 0.82 mM phosphate in flask studies in buffered medium containing rock phosphate as sole P source. In fermenter studies, similar phenotype was observed under aerobic conditions. However, under microaerobic conditions, no citrate was detected and P release was not observed. Therefore, an artificial citrate gene cluster containing Vitreoscilla hemoglobin (vgb) gene under its native promoter, along with artificial citrate operon under constitutive tac promoter, was constructed and transformed into E. hormaechei DHRSS. This transformant secreted 9 mM citric acid under microaerobic conditions and released 1.0 mM P. Thus, incorporation of citrate operon along with vgb gene improves MPS ability of E. hormaechei DHRSS under buffered, microaerobic conditions mimicking rhizospheric environment.

  1. Identification of basic amino acid residues important for citrate binding by the periplasmic receptor domain of the sensor kinase CitA.

    PubMed

    Gerharz, Tanja; Reinelt, Stefan; Kaspar, Sibylle; Scapozza, Leonardo; Bott, Michael

    2003-05-20

    The sensor kinase CitA and the response regulator CitB of Klebsiella pneumoniae form the paradigm of a subfamily of bacterial two-component regulatory systems that are capable of sensing tri- or dicarboxylates in the environment and then induce transporters for the uptake of these compounds. We recently showed that the separated periplasmic domain of CitA, termed CitAP (encompasses residues 45-176 supplemented with an N-terminal methionine residue and a C-terminal hexahistidine tag), is a highly specific citrate receptor with a K(d) of 5.5 microM at pH 7. To identify positively charged residues involved in binding the citrate anion, each of the arginine, lysine, and histidine residues in CitAP was exchanged for alanine, and the resulting 17 muteins were analyzed by isothermal titration calorimetry (ITC). In 12 cases, the K(d) for citrate was identical to that of wild-type CitAP or slightly changed (3.9-17.2 microM). In one case (R98A), the K(d) was 6-fold decreased (0.8 microM), whereas in four cases (R66A, H69A, R107A, and K109A) the K(d) was 38- to >300-fold increased (0.2 to >1 mM). The secondary structure of the latter five proteins in their apo-form as deduced from far-UV circular dichroism (CD) spectra did not differ from the apo-form of wild-type CitAP; however, all of them showed an increased thermostability. Citrate increased the melting point (T(m)) of wild-type CitAP and mutein R98A by 6.2 and 9.5 degrees C, respectively, but had no effect on the T(m) of the four proteins with disturbed binding. Three of the residues important for citrate binding (R66, H69, and R107) are highly conserved in the CitA subfamily of sensor kinases, indicating that they might be involved in ligand binding by many of these sensor kinases.

  2. Investigation of Possible Maillard Reaction Between Acyclovir and Dextrose upon Dilution Prior to Parenteral Administration.

    PubMed

    Siahi Shadbad, Mohammad Reza; Ghaderi, Faranak; Hatami, Leila; Monajjemzadeh, Farnaz

    2016-12-01

    In this study the stability of parenteral acyclovir (ACV) when diluted in dextrose (DEX) as large volume intravenous fluid preparation (LVIF) was evaluated and the possible Maillard reaction adducts were monitored in the recommended infusion time. Different physicochemical methods were used to evaluate the Maillard reaction of dextrose with ACV to track the reaction in real infusion condition. Other large volume intravenous fluids were checked regarding the diluted drug stability profile. Differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), and mass data proved the reaction of glucose with dextrose. A Maillard-specific high performance liquid chromatography (HPLC) method was used to track the reaction in real infusion condition in vitro. The nucleophilic reaction occurred in diluted parenteral preparations of acyclovir in 5% dextrose solutions. The best diluent solution was also selected as sodium chloride and introduced based on drug stability and also its adsorption onto different infusion sets (PVC or non PVC) to provide an acceptable administration protocol in clinical practices. Although, the Maillard reaction was proved and successfully tracked in diluted solutions, and the level of drug loss when diluted in dextrose was reported to be between 0.27 up to 1.03% of the initial content. There was no drug adsorption to common infusion sets. The best diluent for parenteral acyclovir is sodium chloride large volume intravenous fluid.

  3. Stability of lidocaine hydrochloride in 5% dextrose injection in plastic bags

    SciTech Connect

    Smith, F.M.; Nuessle, N.O.

    1981-11-01

    The stability of lidocaine injection mixed with 5% dextrose injection and refrigerated or stored at room temperature was studied. Lidocaine injection was added to 5% dextrose injection to provide a lidocaine hydrochloride concentration of 4 mg/ml. Samples were assayed for lidocaine and its degradation product, 2,6-dimethylaniline, after 30, 60, and 120 days of storage at room temperature (30 degrees C) and refrigerated temperature (4 degrees C). The analysis was by a stability-indicating HPLC method. Degradation product 2,6-dimethylaniline was not detected at any assay time at either temperature. No statistically significant loss of lidocaine occurred at either temperature. Lidocaine hydrochloride injection is chemically stable for up to 120 days at either 30 degrees C or 4 degrees C when mixed with 5% dextrose injection in plastic infusion bags.

  4. Postprandial oxidative stress in response to dextrose and lipid meals of differing size

    PubMed Central

    2010-01-01

    We have recently noted that ingestion of dietary lipid (in the form of heavy whipping cream) leads to greater oxidative stress than dietary carbohydrate (in the form of dextrose), when consumed in isocaloric amounts. Objective In the present investigation we attempted to replicate our work and also to determine the oxidative stress response to dextrose and lipid meals of two different kilocalorie (kcal) amounts. Design Nine young (22 ± 2 years), healthy men consumed in a random order, cross-over design one of four meals/drinks: dextrose at 75 g (300 kcals), dextrose at 150 g (600 kcals), lipid at 33 g (300 kcals), lipid at 66 g (600 kcals). Blood samples were collected Pre meal, and at 30 min, 60 min, 120 min, and 180 min post meal. Samples were assayed for glucose, triglycerides (TAG), malondialdehyde (MDA), and hydrogen peroxide (H2O2). Area under the curve (AUC) was calculated for each variable, and a 4 × 5 ANOVA was utilized to further analyze data. Results A meal × time effect (p = 0.0002) and a time effect was noted for glucose (p < 0.0001; 30 min > Pre, 1 hr, 2 hr, and 3 hr). The dextrose meals primarily contributed to this time effect. No other effects were noted for glucose (p > 0.05). A meal effect was noted for TAG (p = 0.01; 66 g lipid meal > 75 g and 150 g dextrose meals). No other effects were noted for TAG (p > 0.05). An AUC effect was noted for MDA (p = 0.04; 66 g lipid meal > 75 g and 150 g dextrose meals). A meal × time effect (p = 0.02) and a meal effect was noted for MDA (p = 0.004; 66 g lipid meal > 75 g and 150 g dextrose meals). No time effect was noted for MDA (p = 0.72). An AUC effect was noted for H2O2 (p = 0.0001; 66 g lipid meal > 33 g lipid meal and 75 g and 150 g dextrose meals). A meal × time effect (p = 0.0002), a meal effect (p < 0.0001; 66 g lipid meal > 33 g lipid meal and 75 g and 150 g dextrose meals), and a time effect was noted for H2O2 (p < 0.0001; 2 hr > Pre, 30 min, and 1 hr; 3 hr > Pre). The time effect for H2O2 was

  5. Acute effects of calcium carbonate, calcium citrate and potassium citrate on markers of calcium and bone metabolism in young women.

    PubMed

    Karp, Heini J; Ketola, Maarit E; Lamberg-Allardt, Christel J E

    2009-11-01

    Both K and Ca supplementation may have beneficial effects on bone through separate mechanisms. K in the form of citrate or bicarbonate affects bone by neutralising the acid load caused by a high protein intake or a low intake of alkalising foods, i.e. fruits and vegetables. Ca is known to decrease serum parathyroid hormone (S-PTH) concentration and bone resorption. We compared the effects of calcium carbonate, calcium citrate and potassium citrate on markers of Ca and bone metabolism in young women. Twelve healthy women aged 22-30 years were randomised into four controlled 24 h study sessions, each subject serving as her own control. At the beginning of each session, subjects received a single dose of calcium carbonate, calcium citrate, potassium citrate or a placebo in randomised order. The diet during each session was identical, containing 300 mg Ca. Both the calcium carbonate and calcium citrate supplement contained 1000 mg Ca; the potassium citrate supplement contained 2250 mg K. Markers of Ca and bone metabolism were followed. Potassium citrate decreased the bone resorption marker (N-terminal telopeptide of type I collagen) and increased Ca retention relative to the control session. Both Ca supplements decreased S-PTH concentration. Ca supplements also decreased bone resorption relative to the control session, but this was significant only for calcium carbonate. No differences in bone formation marker (bone-specific alkaline phosphatase) were seen among the study sessions. The results suggest that potassium citrate has a positive effect on the resorption marker despite low Ca intake. Both Ca supplements were absorbed well and decreased S-PTH efficiently.

  6. DEXTROSE-TEMPLATED MICROWAVE-ASSISTED COMBUSTION SYNTHESIS OF SPONGY METAL OXIDES

    EPA Science Inventory

    Microwave-assisted combustion synthesis of porous nanocrystalline titania and carbon coated titania is reported using dextrose as template and the product was compared with the one obtained using conventional heating furnace. Out of three compositions viz., 1:1, 1:3, and 1:5 (met...

  7. Citrate uptake into Pectobacterium atrosepticum is critical for bacterial virulence.

    PubMed

    Urbany, Claude; Neuhaus, H Ekkehard

    2008-05-01

    To analyze whether metabolite import into Pectobacterium atrosepticum cells affects bacterial virulence, we investigated the function of a carrier which exhibits significant structural homology to characterized carboxylic-acid transport proteins. The corresponding gene, ECA3984, previously annotated as coding for a Na(+)/sulphate carrier, in fact encodes a highly specific citrate transporter (Cit1) which is energized by the proton-motive force. Expression of the cit1 gene is stimulated by the presence of citrate in the growth medium and is substantial during growth of P. atrosepticum on potato tuber tissue. Infection of tuber tissue with P. atrosepticum leads to reduced citrate levels. P. atrosepticum insertion mutants, lacking the functional Cit1 protein, did not grow in medium containing citrate as the sole carbon source, showed a substantially reduced ability to macerate potato tuber tissue, and did not provoke reduced citrate levels in the plant tissue upon infection. We propose that citrate uptake into P. atrosepticum is critical for full bacterial virulence.

  8. Comparative transcriptome analysis reveals a global insight into molecular processes regulating citrate accumulation in sweet orange (Citrus sinensis).

    PubMed

    Lu, Xiaopeng; Cao, Xiongjun; Li, Feifei; Li, Jing; Xiong, Jiang; Long, Guiyou; Cao, Shangyin; Xie, Shenxi

    2016-12-01

    Citrate, the predominant organic acid in citrus, determines the taste of these fruits. However, little is known about the synergic molecular processes regulating citrate accumulation. Using 'Dahongtiancheng' (Citrus sinensis) and 'Bingtangcheng' (C. sinensis) with significant difference in citrate, the objectives of this study were to understand the global mechanisms of high-citrate accumulation in sweet orange. 'Dahongtiancheng' and 'Bingtangcheng' exhibit significantly different patterns in citrate accumulation throughout fruit development, with the largest differences observed at 50-70 days after full bloom (DAFB). Comparative transcriptome profiling was performed for the endocarps of both cultivars at 50 and 70 DAFB. Over 34.5 million clean reads per library were successfully mapped to the reference database and 670-2630 differentially expressed genes (DEGs) were found in four libraries. Among the genes, five transcription factors were ascertained to be the candidates regulating citrate accumulation. Functional assignments of the DEGs indicated that photosynthesis, the citrate cycle and amino acid metabolism were significantly altered in 'Dahongtiancheng'. Physiological and molecular analyses suggested that high photosynthetic efficiency and partial impairment of citrate catabolism were crucial for the high-citrate trait, and amino acid biosynthesis was one of the important directions for citrate flux. The results reveal a global insight into the gene expression changes in a high-citrate compared with a low-citrate sweet orange. High accumulating efficiency and impaired degradation of citrate may be associated with the high-citrate trait of 'Dahongtiancheng'. Findings in this study increase understanding of the molecular processes regulating citrate accumulation in sweet orange.

  9. A turn-on fluorescent indicator for citrate with micromolar sensitivity.

    PubMed

    Burguete, M Isabel; Galindo, Francisco; Luis, Santiago V; Vigara, Laura

    2007-09-28

    A turn-on fluorescent indicator for citric acid (citrate) has been developed, displaying high emission enhancement (+1500%) and low interference by other carboxylates. The sensor is based on the non-emissive copper(II) complex of a fluorescent amino amide, which, upon addition of citrate decomplexates to yield the emissive ligand. The detection limit estimated for this new chemosensing system is about 0.5 microM. This novel approach to the analysis of citrate constitutes an alternative ca. 10(2)-10(3) times more sensitive than the standard method based on the enzyme citrate lyase.

  10. Modeling and optimising alcohol production by fermentation of dextrose-xylose mixed feed using a fluorosensor.

    PubMed

    Sundaram, S; Sailaja, D; Kalpana, N

    1997-01-01

    Dextrose with differing amounts of xylose (mixed substrate medium) has been fermented at 28 degree Celsius with sacchromyces cerevisiae (Baker's Yeast) as seeding. The progress of the reaction was recorded by measuring the fluorescent signal due to intracellular reduced nicotinamide adenine di nucleotide (NADH) present in the cells with a Dr. Ingold (Switzerland) fluorosensor which has an excitation wavelength of 360 nm and measurement wavelength of 450 nm. The concentration of xylose in the xylose-dextrose feed was varied from 0.7% to 5.0% by weight. The optimum concentration of xylose at which the production of alcohol was a maximum was found to be 3.4 percent xylose. The fluorescent voltage data for different concentration of xylose fitted a first order model with an average absolute deviation of less than one percent. Development of this model is useful in design of model predictive controllers.

  11. Reduction of neonatal pain following administration of 25% lingual dextrose: a randomized control trial.

    PubMed

    Nimbalkar, Somashekhar; Sinojia, Ankit; Dongara, Ashish

    2013-06-01

    Neonates experience painful procedures during routine care. Orally administered, sweet tasting solutions are commonly used in management of neonatal pain. We conducted a double-blind randomized control trial in neonates admitted to Neonatal Intensive Care Unit of Shri Krishna Hospital, Karamsad-Gujarat-India, of lingual administration of 25% dextrose vs. no intervention, to evaluate reduction of pain following oropharyngeal infant feeding tube insertions. Pain was assessed using Premature Infant Pain Profile score. Almost all the patients in the control group (98%) experienced moderate-to-severe pain as compared with the intervention group (71%). Mean Premature Infant Pain Profile score was statistically significantly lower in the intervention group (8.21) as compared with control group (10.31). (p < 0.001, 95% CI 1.090-3.102). Lingual 25% dextrose is an effective analgesic for relieving pain during orogastric tube insertion.

  12. Identification of two distinct Bacillus subtilis citrate synthase genes.

    PubMed

    Jin, S; Sonenshein, A L

    1994-08-01

    Two distinct Bacillus subtilis genes (citA and citZ) were found to encode citrate synthase isozymes that catalyze the first step of the Krebs cycle. The citA gene was cloned by genetic complementation of an Escherichia coli citrate synthase mutant strain (W620) and was in a monocistronic transcriptional unit. A divergently transcribed gene, citR, could encode a protein with strong similarity to the bacterial LysR family of regulatory proteins. A null mutation in citA had little effect on citrate synthase enzyme activity or sporulation. The residual citrate synthase activity was purified from a citA null mutant strain, and the partial amino acid sequence for the purified protein (CitZ) was determined. The citZ gene was cloned from B. subtilis chromosomal DNA by using a PCR-generated probe synthesized with oligonucleotide primers derived from the partial amino acid sequence of purified CitZ. The citZ gene proved to be the first gene in a tricistronic cluster that also included citC (coding for isocitrate dehydrogenase) and citH (coding for malate dehydrogenase). A mutation in citZ caused a substantial loss of citrate synthase enzyme activity, glutamate auxotrophy, and a defect in sporulation.

  13. The Effects of Prolotherapy With Hypertonic Dextrose Versus Prolozone (Intraarticular Ozone) in Patients With Knee Osteoarthritis

    PubMed Central

    Hashemi, Masoud; Jalili, Parviz; Mennati, Shirin; Koosha, Alireza; Rohanifar, Ramin; Madadi, Firouz; Razavi, Seyed Sajad; Taheri, Farinaz

    2015-01-01

    Background: Knee osteoarthritis (KOA) is a common disabling disease. Limited studies have demonstrated that prolotherapy with dextrose or with prolozone can be helpful in the treatment of patients with KOA. Objectives: In the current study, we compared the results between these two treatment methods. Patients and Methods: In the current randomized clinical trial, 80 patients with mild to moderate KOA were randomly assigned equally into two groups (ozone group and dextrose group). In each group, injections were repeated three times with 10-day intervals. Before the treatment and 3 months after the injections, the pain intensity was measured by using a visual analogue scale and the Western Ontario and McMaster university arthritis index scores. Finally, the results were compared between the two groups. Results: In the two groups, the pain intensity and WOMAC scores significantly decreased and increased, respectively (P < 0.001). However, there was no significant difference between the two groups. Conclusions: Prolotherapy with dextrose and with prolozone result in the same pain relief or functional improvement in patients with mild to moderate KOA. PMID:26587401

  14. Hypocaloric enteral nutrition protects against hypoglycemia associated with intensive insulin therapy better than intravenous dextrose.

    PubMed

    Kauffmann, Rondi M; Hayes, Rachel M; VanLaeken, Amanda H; Norris, Patrick R; Diaz, Jose J; May, Addison K; Collier, Bryan R

    2014-11-01

    Intensive insulin therapy treats hyperglycemia but increases the risk of hypoglycemia. Typically, intravenous dextrose is given to prevent hypoglycemia; however, enteral nutrition is preferred. We hypothesized that the provision of hypocaloric enteral nutrition would protect against hypoglycemia. A retrospective analysis was performed evaluating patients treated with intensive insulin therapy comparing the use of enteral nutrition versus a dextrose-only intravenous solution. Nutrition in the 2 hours before each blood glucose test was assessed, and the association with hypoglycemia (50 mg/dL or less) evaluated. Risk of hypoglycemia as a function of nutrition type and rate was estimated by multivariable regression. A total of 26,140 blood glucose tests were collected on 1289 patients. Hypoglycemia occurred in 6.4 per cent of patients. In regression models, enteral nutrition was the strongest protective factor against hypoglycemia (P < 0.001) with the largest risk reduction (steepest portion of the curve) occurring at 60 per cent goal. Hypocaloric enteral nutrition showed a greater risk reduction than a peripheral dextrose-only intravenous solution alone. In the setting of intensive insulin therapy, the provision of enteral nutrition, even if hypocaloric, is sufficient to protect against hypoglycemia. Future prospective studies should evaluate the efficacy of enteral nutrition in reducing the risk of hypoglycemia and whether lower rates of hypoglycemia correspond to improved outcomes.

  15. Hypocaloric Enteral Nutrition Protects Against Hypoglycemia Associated with Intensive Insulin Therapy Better Than Intravenous Dextrose

    PubMed Central

    Kauffmann, Rondi M.; Hayes, Rachel M.; Vanlaeken, Amanda H.; Norris, Patrick R.; Diaz, Jose J.; May, Addison K.; Collier, Bryan R.

    2015-01-01

    Intensive insulin therapy treats hyperglycemia but increases the risk of hypoglycemia. Typically, intravenous dextrose is given to prevent hypoglycemia; however, enteral nutrition is preferred. We hypothesized that the provision of hypocaloric enteral nutrition would protect against hypoglycemia. A retrospective analysis was performed evaluating patients treated with intensive insulin therapy comparing the use of enteral nutrition versus a dextrose-only intravenous solution. Nutrition in the 2 hours before each blood glucose test was assessed, and the association with hypoglycemia (50 mg/dL or less) evaluated. Risk of hypoglycemia as a function of nutrition type and rate was estimated by multivariable regression. A total of 26,140 blood glucose tests were collected on 1289 patients. Hypoglycemia occurred in 6.4 per cent of patients. In regression models, enteral nutrition was the strongest protective factor against hypoglycemia (P < 0.001) with the largest risk reduction (steepest portion of the curve) occurring at 60 per cent goal. Hypocaloric enteral nutrition showed a greater risk reduction than a peripheral dextrose-only intravenous solution alone. In the setting of intensive insulin therapy, the provision of enteral nutrition, even if hypocaloric, is sufficient to protect against hypoglycemia. Future prospective studies should evaluate the efficacy of enteral nutrition in reducing the risk of hypoglycemia and whether lower rates of hypoglycemia correspond to improved outcomes. PMID:25347500

  16. A Process-Based Model of TCA Cycle Functioning to Analyze Citrate Accumulation in Pre- and Post-Harvest Fruits

    PubMed Central

    Etienne, Audrey; Génard, Michel; Bugaud, Christophe

    2015-01-01

    Citrate is one of the most important organic acids in many fruits and its concentration plays a critical role in organoleptic properties. The regulation of citrate accumulation throughout fruit development, and the origins of the phenotypic variability of the citrate concentration within fruit species remain to be clarified. In the present study, we developed a process-based model of citrate accumulation based on a simplified representation of the TCA cycle to predict citrate concentration in fruit pulp during the pre- and post-harvest stages. Banana fruit was taken as a reference because it has the particularity of having post-harvest ripening, during which citrate concentration undergoes substantial changes. The model was calibrated and validated on the two stages, using data sets from three contrasting cultivars in terms of citrate accumulation, and incorporated different fruit load, potassium supply, and harvest dates. The model predicted the pre and post-harvest dynamics of citrate concentration with fairly good accuracy for the three cultivars. The model suggested major differences in TCA cycle functioning among cultivars during post-harvest ripening of banana, and pointed to a potential role for NAD-malic enzyme and mitochondrial malate carriers in the genotypic variability of citrate concentration. The sensitivity of citrate accumulation to growth parameters and temperature differed among cultivars during post-harvest ripening. Finally, the model can be used as a conceptual basis to study citrate accumulation in fleshy fruits and may be a powerful tool to improve our understanding of fruit acidity. PMID:26042830

  17. Regulation of anaerobic citrate metabolism in Klebsiella pneumoniae.

    PubMed

    Bott, M; Meyer, M; Dimroth, P

    1995-11-01

    Three enzymes are specifically required for uptake and catabolism of citrate by Klebsiella pneumoniae under anaerobic conditions: a Na+ -dependent citrate carrier (CitS), citrate lyase (CitDEF), and the Na+ pump oxaloacetate decarboxylase (OadGAB). The corresponding genes are clustered on the chromosome, with the citCDEFG genes located upstream and divergent to the citS-oadGAB genes. We found that expression of citS from its native promoter in Escherichia coli requires the DNA region downstream of oadB. Nucleotide sequence analysis of this region revealed the presence of two adjacent genes, citA and citB. By sequence similarity, the predicted CitA and CitB proteins were identified as members of the two-component regulatory systems. The sensor kinase CitA contained, in the N-terminal half, two putative transmembrane helices which enclosed a presumably periplasmic domain of about 130 amino acids. The C-terminal half of the response regulator CitB harboured a helix-turn-helix motif typical of DNA-binding proteins. K. pneumoniae citB null mutants were unable to grow anaerobically with citrate as the sole carbon and energy source (Cit- phenotype). When cultivated anaerobically with citrate plus glycerol, all of the citrate-specific fermentation enzymes were synthesized in the wild type, but not in the citB mutants. This showed that citS, oadGAB and citDEF required the CitB protein for expression and therefore are part of a regulon. In the wild type, synthesis of CitS, oxaloacetate decarboxylase and citrate lyase was dependent on the presence of citrate, sodium ions and a low oxygen tension. In a citA null mutant which expressed citB constitutively at high levels, none of these signals was required for the formation of the citrate fermentation enzymes. This result suggested that citrate, Na+, and oxygen exerted their regulatory effects via the CitA/CitB system. In the presence of these signals, the citAB gene products induced their own synthesis. The positive

  18. Simplified citrate anticoagulation for high-flux hemodialysis.

    PubMed

    Apsner, R; Buchmayer, H; Lang, T; Unver, B; Speiser, W; Sunder-Plassmann, G; Hörl, W H

    2001-11-01

    In a randomized crossover trial, we compared a simple citrate anticoagulation protocol for high-flux hemodialysis with standard anticoagulation by low-molecular-weight heparin (dalteparin). Primary end points were urea reduction rate (URR), Kt/V, and control of electrolyte and acid-base homeostasis. Secondary end points were bleeding time at vascular puncture sites and markers of activation of platelets, coagulation, and fibrinolysis. Solute removal during citrate dialysis was excellent (URR, 0.71 +/- 0.06; Kt/V, 1.55 +/- 0.3) and similar to results of conventional bicarbonate hemodialysis anticoagulation with dalteparin (URR, 0.72 +/- 0.04; Kt/V, 1.56 +/- 0.2). Electrolyte control was effective with both anticoagulation regimens, and total and ionized calcium, sodium, potassium, and phosphate concentrations at the end of dialysis did not differ. Alkalemia was less frequent after citrate than conventional dialysis (pH 7.5 in 25% versus 62% of patients; mean pH at end of dialysis, 7.46 +/- 0.06 versus 7.51 +/- 0.07; P < 0.01). Bleeding time at puncture sites was shorter by 30% after citrate compared with dalteparin anticoagulation (5.43 +/- 2.80 versus 7.86 +/- 2.93 minutes; P < 0.001). Activation of platelets, coagulation, and fibrinolysis was modest for both treatments and occurred mainly within the dialyzer during dalteparin treatment and in the vascular-access region during citrate anticoagulation. Citrate-related adverse events were not observed. We conclude that citrate anticoagulation for high-flux hemodialysis is feasible and safe using a simple infusion protocol.

  19. Peroxisomal and mitochondrial citrate synthase in CAM plants.

    PubMed

    Zafra, M F; Segovia, J L; Alejandre, M J; García-Peregrín, E

    1981-12-01

    Citrate synthase wa studied for the first time in peroxisomes and mitochondria of crassulacean acid metabolism plants. Cellular organelles were isolated from Agave americana leaves by sucrose density gradient centrifugation and characterized by the use of catalase and cytochrome oxidase as marker enzymes, respectively. 48,000 X g centrifugation caused the breakdown of the cellular organelles. The presence of a glyoxylate cycle enzyme (citrate synthase) and a glycollate pathway enzyme (catalase) in the same organelles, besides the absence of another glyoxalate cycle enzyme (malate synthase) is reported for the first time, suggesting that peroxisomal and glyoxysomal proteins are synthesized at the same time and housed in he same organelle.

  20. Total synthesis of alkyl citrate natural products.

    PubMed

    Rizzacasa, Mark A; Sturgess, Dayna

    2014-03-07

    This review highlights the synthesis of members of the alkyl citrate family of natural products. The focus is on the stereoselective construction of the alkyl citrate moiety common to these compounds.

  1. Characterization of citrate utilization in Corynebacterium glutamicum by transcriptome and proteome analysis.

    PubMed

    Polen, Tino; Schluesener, Daniela; Poetsch, Ansgar; Bott, Michael; Wendisch, Volker F

    2007-08-01

    Corynebacterium glutamicum grows aerobically on a variety of carbohydrates and organic acids as single or combined sources of carbon and energy. To characterize the citrate utilization in C. glutamicum on a genomewide scale, a comparative analysis was carried out by combining transcriptome and proteome analysis. In cells grown on citrate, transcriptome analysis revealed highest expression changes for two different citrate-uptake systems encoded by citM and tctCBA, whereas genes encoding uptake systems for the glucose- (ptsG), sucrose- (ptsS) and fructose- (ptsF) specific PTS components and permeases for gluconate (gntP) and glutamate (gluC) displayed decreased mRNA levels in citrate-grown cells. This pattern was also observed when cells grown in Luria-Bertani (LB) medium plus citrate were compared with cells grown in LB medium, indicating some kind of catabolite repression. Genes encoding enzymes of the tricarboxylic acid cycle (aconitase, succinyl-CoA synthetase, succinate dehydrogenase and fumarase), malic enzyme, PEP carboxykinase, gluconeogenic glyceraldehyde-3-phosphate dehydrogenase and ATP synthase displayed increased expression in cells grown on citrate. Accordingly, proteome analysis revealed elevated protein levels of these enzymes and showed a good correlation with the mRNA levels. In conclusion, this study revealed the citrate stimulon in C. glutamicum and the regulated central metabolic genes when grown on citrate.

  2. 21 CFR 582.1625 - Potassium citrate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Potassium citrate. 582.1625 Section 582.1625 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1625 Potassium citrate. (a) Product. Potassium citrate. (b) Conditions of use....

  3. 21 CFR 582.6625 - Potassium citrate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Potassium citrate. 582.6625 Section 582.6625 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Potassium citrate. (a) Product. Potassium citrate. (b) Conditions of use. This substance is...

  4. 21 CFR 582.6625 - Potassium citrate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Potassium citrate. 582.6625 Section 582.6625 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Potassium citrate. (a) Product. Potassium citrate. (b) Conditions of use. This substance is...

  5. 21 CFR 582.1625 - Potassium citrate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Potassium citrate. 582.1625 Section 582.1625 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1625 Potassium citrate. (a) Product. Potassium citrate. (b) Conditions of use....

  6. 21 CFR 582.1625 - Potassium citrate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Potassium citrate. 582.1625 Section 582.1625 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1625 Potassium citrate. (a) Product. Potassium citrate. (b) Conditions of use....

  7. 21 CFR 582.1625 - Potassium citrate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Potassium citrate. 582.1625 Section 582.1625 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1625 Potassium citrate. (a) Product. Potassium citrate. (b) Conditions of use....

  8. 21 CFR 582.1625 - Potassium citrate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Potassium citrate. 582.1625 Section 582.1625 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1625 Potassium citrate. (a) Product. Potassium citrate. (b) Conditions of use....

  9. 21 CFR 582.6625 - Potassium citrate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Potassium citrate. 582.6625 Section 582.6625 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Potassium citrate. (a) Product. Potassium citrate. (b) Conditions of use. This substance is...

  10. 21 CFR 582.6625 - Potassium citrate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Potassium citrate. 582.6625 Section 582.6625 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Potassium citrate. (a) Product. Potassium citrate. (b) Conditions of use. This substance is...

  11. 21 CFR 582.6625 - Potassium citrate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Potassium citrate. 582.6625 Section 582.6625 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Potassium citrate. (a) Product. Potassium citrate. (b) Conditions of use. This substance is...

  12. 21 CFR 582.6751 - Sodium citrate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Sodium citrate. 582.6751 Section 582.6751 Food and..., FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Sequestrants 2 § 582.6751 Sodium citrate. (a) Product. Sodium citrate. (b) Conditions of use. This substance is generally recognized...

  13. 21 CFR 582.1751 - Sodium citrate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Sodium citrate. 582.1751 Section 582.1751 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS....1751 Sodium citrate. (a) Product. Sodium citrate. (b) Conditions of use. This substance is...

  14. 21 CFR 582.1751 - Sodium citrate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Sodium citrate. 582.1751 Section 582.1751 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS....1751 Sodium citrate. (a) Product. Sodium citrate. (b) Conditions of use. This substance is...

  15. 21 CFR 582.6751 - Sodium citrate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Sodium citrate. 582.6751 Section 582.6751 Food and..., FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Sequestrants 2 § 582.6751 Sodium citrate. (a) Product. Sodium citrate. (b) Conditions of use. This substance is generally recognized...

  16. 21 CFR 582.1751 - Sodium citrate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Sodium citrate. 582.1751 Section 582.1751 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS....1751 Sodium citrate. (a) Product. Sodium citrate. (b) Conditions of use. This substance is...

  17. 21 CFR 582.6751 - Sodium citrate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Sodium citrate. 582.6751 Section 582.6751 Food and..., FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Sequestrants 2 § 582.6751 Sodium citrate. (a) Product. Sodium citrate. (b) Conditions of use. This substance is generally recognized...

  18. 21 CFR 582.6751 - Sodium citrate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Sodium citrate. 582.6751 Section 582.6751 Food and..., FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Sequestrants 2 § 582.6751 Sodium citrate. (a) Product. Sodium citrate. (b) Conditions of use. This substance is generally recognized...

  19. 21 CFR 582.1751 - Sodium citrate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Sodium citrate. 582.1751 Section 582.1751 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS....1751 Sodium citrate. (a) Product. Sodium citrate. (b) Conditions of use. This substance is...

  20. 21 CFR 582.1751 - Sodium citrate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Sodium citrate. 582.1751 Section 582.1751 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS....1751 Sodium citrate. (a) Product. Sodium citrate. (b) Conditions of use. This substance is...

  1. 21 CFR 582.6751 - Sodium citrate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Sodium citrate. 582.6751 Section 582.6751 Food and..., FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Sequestrants 2 § 582.6751 Sodium citrate. (a) Product. Sodium citrate. (b) Conditions of use. This substance is generally recognized...

  2. Differentiation of Cryptococcus neoformans serotypes A and D using creatinine dextrose bromothymol blue thymine medium.

    PubMed

    Irokanulo, E A; Akueshi, C O; Makinde, A A

    1994-06-01

    A serotype differentiation of the encapsulated yeast Cryptococcus neoformans is described using creatinine dextrose bromothymol blue thymine (CDBT) medium. On CDBT medium C. neoformans serotype D grew as bright red colonies, turning the medium a bright orange after five days incubation at 28 degrees C. C. neoformans serotype A grew as pale colonies with no apparent colour effect on the medium. Serotypes B and C caused a slight greening of the medium. The reaction of the four serotypes of C. neoformans on CDBT medium is considered useful in the differentiation of the closely related serotype A and D.

  3. Citrate and the conversion of carbohydrate in fat. The activities of citrate-cleavage enzyme and acetate thiokinase in livers of starved and re-fed rats

    PubMed Central

    Kornacker, Melodee S.; Lowenstein, J. M.

    1965-01-01

    1. The activity of citrate-cleavage enzyme varies in accordance with the nutritional state of the animal. It is suppressed on starvation and restored on re-feeding after starvation. 2. The increase in enzyme activity that occurs on re-feeding starved animals depends on the diet. It is largest on diets high in carbohydrate and low in fat, and smallest on diets high in fat. Intermediate increases are obtained with balanced diets. 3. The ratio of activities of citrate-cleavage enzyme to acetate thiokinase varies from 2·5 for animals maintained on a balanced diet to 20 for animals re-fed with a diet high in carbohydrate. 4. The changes in activity of citrate-cleavage enzyme correlate with changes in the rate of fatty acid synthesis and provide evidence for the involvement of the citrate-cleavage reaction in fatty acid synthesis. PMID:14342232

  4. Prospective Evaluation of Intra-Articular Dextrose Prolotherapy for Treatment of Osteoarthritis in Dogs.

    PubMed

    Sherwood, J Matthew; Roush, James K; Armbrust, Laura J; Renberg, Walter C

    2017-03-14

    The objective of this study was to evaluate intra-articular dextrose prolotherapy for osteoarthritis of the elbow or stifle in dogs in a randomized, double-blind, placebo-controlled, prospective pilot study. Seventeen dogs were evaluated with 10 meeting inclusion criteria for this study. Evaluations included orthopedic exam, visual lameness scoring, Canine Brief Pain Inventory (CBPI), goniometry, kinetic gait analysis, and radiography. Initial lameness score, age, body weight, duration of lameness, and CBPI scores did not differ between groups. Change in CBPI pain severity score in the prolotherapy group from wk 6-12 was significantly less improved than in the placebo group, with no other significant differences in pain severity or pain interference scores between groups. Range of motion and radiographic scores did not differ between groups at any time. Mean kinetic forces improved in prolotherapy dogs but were not significantly different between treatment groups at any time. Although easily performed and well-tolerated, there were no statistically significant benefits of dextrose prolotherapy for treatment of osteoarthritis of the elbow and stifle in dogs. Post hoc power analysis of these sample means and standard deviations found that 29-106 animals per group would be necessary to demonstrate significant differences in kinetic forces, providing useful guidance for future studies.

  5. Citrate and Sugar Cofermentation in Leuconostoc oenos, a (sup13)C Nuclear Magnetic Resonance Study

    PubMed Central

    Ramos, A.; Santos, H.

    1996-01-01

    (sup13)C nuclear magnetic resonance spectroscopy was used to investigate citrate-glucose cometabolism in nongrowing cell suspensions of the wine lactic acid bacterium Leuconostoc oenos. The use of isotopically enriched substrates allowed us to identify and quantify in the end products the carbon atoms derived from each of the substrates supplied; furthermore, it was possible to differentiate between products derived from the metabolism of endogenous carbon reserves and those derived from external substrates. Citrate-sugar cometabolism was also monitored in dilute cell suspensions for comparison with the nuclear magnetic resonance results. A clear metabolic shift of the end products from glucose metabolism was observed when citrate was provided along with glucose: ethanol was replaced by acetate, and 2,3-butanediol was produced. Reciprocally, the production of lactate and 2,3-butanediol from citrate was increased in the presence of glucose. When citrate was cometabolized with glucose, a 10-fold reduction in the intracellular concentration of glucose-6-phosphate was observed, a result in line with the observed citrate-induced stimulation of glucose consumption. The presence of citrate provided additional pathways for NADP(sup+) regeneration and allowed the diversion of sugar carbon to reactions in which ATP was synthesized. The increased growth rates and maximal biomass yields of L. oenos growing on citrate-glucose mixtures resulted from increased ATP synthesis both by substrate-level phosphorylation and by a chemiosmotic mechanism. PMID:16535363

  6. Photochemical degradation of citrate buffers leads to covalent acetonation of recombinant protein therapeutics

    PubMed Central

    Valliere-Douglass, John F; Connell-Crowley, Lisa; Jensen, Randy; Schnier, Paul D; Trilisky, Egor; Leith, Matt; Follstad, Brian D; Kerr, Jennifer; Lewis, Nathan; Vunnum, Suresh; Treuheit, Michael J; Balland, Alain; Wallace, Alison

    2010-01-01

    Novel acetone and aldimine covalent adducts were identified on the N-termini and lysine side chains of recombinant monoclonal antibodies. Photochemical degradation of citrate buffers, in the presence of trace levels of iron, is demonstrated as the source of these modifications. The link between degradation of citrate and the observed protein modifications was conclusively established by tracking the citrate decomposition products and protein adducts resulting from photochemical degradation of isotope labeled 13C citrate by mass spectrometry. The structure of the acetone modification was determined by nuclear magnetic resonance (NMR) spectroscopy on modified–free glycine and found to correspond to acetone linked to the N-terminus of the amino acid through a methyl carbon. Results from mass spectrometric fragmentation of glycine modified with an acetone adduct derived from 13C labeled citrate indicated that the three central carbons of citrate are incorporated onto protein amines in the presence of iron and light. While citrate is known to stoichiometrically decompose to acetone and CO2 through various intermediates in photochemical systems, it has never been shown to be a causative agent in protein carbonylation. Our results point to a previously unknown source for the generation of reactive carbonyl species. This work also highlights the potential deleterious impact of trace metals on recombinant protein therapeutics formulated in citrate buffers. PMID:20836085

  7. Citrate anticoagulation and adverse events.

    PubMed

    De Vos, J; Hombrouckx, R

    2003-01-01

    Several patients with heparin intolerance were dialysed with tri-sodium citrate as anticoagulant without acute clinical problems (good tolerance). After some weeks however problems arose. In all patients an alkalosis developed: the pre dialysis bicarbonate level rose progressively from 27 mmol/l to 40 mmol/l. This could be tempered by lowering the dialysis fluid bicarbonate concentration from 37 mmol/l to 25 mmol/l. A second problem was a progressive rise in pre dialysis sodium level from a mean of 136 mmol/l to 150 mmol/l. Adapting the dialysis fluid sodium concentration from 140 mmol/l towards 132 mmol/l could solve this. The third problem was a progressive rise in serum aluminium level in patients from 3 microg/l to 38 microg/l. After excluding water, concentrate, dialysis fluid, drug intake, etc... as possible sources, we controlled the aluminium level in the glass bottle containing tri-sodium citrate. We noted the very high value of 35,300 microg/l. After replacing the glass bottles with polyvinylchloride bags with a negligible aluminium content, the serum aluminium levels returned back to normal. It is known that citrate chelates the aluminium present in the glass of bottles or vials.

  8. Optimalization of Poly(neutral red) Coated-wire Electrode for Determination of Citrate in Soft Drinks

    PubMed Central

    Broncová, Gabriela; Shishkanova, Tatiana V.; Krondak, Martin; Volf, Radko; Král, Vladimír

    2008-01-01

    This report presents an optimization of potentiometric measurements with citrate-selective electropolymerized poly(neutral red) electrodes. The optimal background electrolyte for these measurements is a TRIS buffer with nitrate at pH 8.5. The electrodes described here exhibit stable and reproducible near-Nernstian response to citrates with a low detection limit of 6 × 10-6 M. Electrodes polymerized from sulfuric acid and acetonitrile are compared in detail. Simple and sensitive method for quantification of citrate in real-life samples by potentiometry with poly(neutral red) electrodes are presented. Data from potentiometric measurements of citrate are compared with capillary electrophoresis. PMID:27879724

  9. Comparative genomics and transcriptome analysis of Aspergillus niger and metabolic engineering for citrate production

    PubMed Central

    Yin, Xian; Shin, Hyun-dong; Li, Jianghua; Du, Guocheng; Liu, Long; Chen, Jian

    2017-01-01

    Despite a long and successful history of citrate production in Aspergillus niger, the molecular mechanism of citrate accumulation is only partially understood. In this study, we used comparative genomics and transcriptome analysis of citrate-producing strains—namely, A. niger H915-1 (citrate titer: 157 g L−1), A1 (117 g L−1), and L2 (76 g L−1)—to gain a genome-wide view of the mechanism of citrate accumulation. Compared with A. niger A1 and L2, A. niger H915-1 contained 92 mutated genes, including a succinate-semialdehyde dehydrogenase in the γ-aminobutyric acid shunt pathway and an aconitase family protein involved in citrate synthesis. Furthermore, transcriptome analysis of A. niger H915-1 revealed that the transcription levels of 479 genes changed between the cell growth stage (6 h) and the citrate synthesis stage (12 h, 24 h, 36 h, and 48 h). In the glycolysis pathway, triosephosphate isomerase was up-regulated, whereas pyruvate kinase was down-regulated. Two cytosol ATP-citrate lyases, which take part in the cycle of citrate synthesis, were up-regulated, and may coordinate with the alternative oxidases in the alternative respiratory pathway for energy balance. Finally, deletion of the oxaloacetate acetylhydrolase gene in H915-1 eliminated oxalate formation but neither influence on pH decrease nor difference in citrate production were observed. PMID:28106122

  10. Gd2O3 nanoparticles stabilized by hydrothermally modified dextrose for positive contrast magnetic resonance imaging

    NASA Astrophysics Data System (ADS)

    Babić-Stojić, Branka; Jokanović, Vukoman; Milivojević, Dušan; Požek, Miroslav; Jagličić, Zvonko; Makovec, Darko; Arsikin, Katarina; Paunović, Verica

    2016-04-01

    Gd2O3 nanoparticles of a few nm in size and their agglomerates dispersed in dextrose derived polymer template were synthesized by hydrothermal treatment. The produced nanosized material was investigated by TEM, FTIR spectroscopy, SQUID measurements and NMR relaxometry. Biological evaluation of this material was done by crystal violet and MTT assays to determine the cell viability. Longitudinal and transverse NMR relaxivities of water diluted Gd2O3 nanoparticle dispersions measured at the magnetic field of 1.5 T, estimated to be r1(Gd2O3)=9.6 s-1 mM-1 in the Gd concentration range 0.1-30 mM and r2(Gd2O3)=17.7 s-1 mM-1 in the lower concentration range 0.1-0.8 mM, are significantly higher than the corresponding relaxivities measured for the standard contrast agent r1(Gd-DTPA)=4.1 s-1 mM-1 and r2(Gd-DTPA)=5.1 s-1 mM-1. The ratio of the two relaxivities for Gd2O3 nanoparticles r2/r1=1.8 is suitable for T1-weighted imaging. Good MRI signal intensities of the water diluted Gd2O3 nanoparticle dispersions were recorded at lower Gd concentrations 0.2-0.8 mM. The Gd2O3 samples did not exert any significant cytotoxic effects at Gd concentrations of 0.2 mM and below. These properties of the produced Gd2O3 nanoparticles in hydrothermally modified dextrose make them promising for potential application in MRI for the design of a positive MRI contrast agent.

  11. 21 CFR 184.1195 - Calcium citrate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... calcium carbonate. It occurs as a fine white, odorless powder and usually contains four moles of water per... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Calcium citrate. 184.1195 Section 184.1195 Food... GRAS § 184.1195 Calcium citrate. (a) Calcium citrate (Ca3(C6H5O7)2·4H2O, CAS Reg. No. 813-0994-095)...

  12. [THE MODERN PROSPECT FOR CITRATE MIXTURES IN THE TREATMENT OF UROLITHIASIS].

    PubMed

    Chepurov, A K; Pronkin, E A; Bolotov, A D

    2015-01-01

    The authors present a review of literature on the use of litholytic citrate medications for conservative management of urolithiasis. Urate urolithiasis is the most common clinical condition encountered by urologists. Citrate agents, in particular Blemaren, not only may be employed in a conservative therapy of uric acid stones, but can also be successfully used in the treatment of the calcium urolithiasis, i.e. mixed composition stones, which is supported by current international urology guidelines.

  13. Iron bioavailability in 8-24-month-old Thai children from a micronutrient-fortified quick-cooking rice containing ferric ammonium citrate or a mixture of ferrous sulphate and ferric sodium ethylenediaminetetraacetic acid.

    PubMed

    Chavasit, Visith; Porasuphatana, Suparat; Suthutvoravut, Umaporn; Zeder, Christroph; Hurrell, Richard

    2015-12-01

    A quick-cooking rice, produced from broken rice, is a convenient ingredient for complementary foods in Thailand. The rice is fortified with micronutrients including iron during the processing procedure, which can cause unacceptable sensory changes. A quick-cooking rice fortified with ferric ammonium citrate (FAC) or a mixture of ferrous sulphate (FeSO4 ) and ferric sodium ethylenediaminetetraacetic acid (NaFeEDTA), with a 2:1 molar ratio of iron from FeSO4  : iron from NaFeEDTA (FeSO4  + NaFeEDTA), gave a product that was organoleptically acceptable. The study compared iron absorption by infants and young children fed with micronutrient-fortified quick-cooking rice containing the test iron compounds or FeSO4 . Micronutrient-fortified quick-cooking rice prepared as a traditional Thai dessert was fed to two groups of 15 8-24-month healthy Thai children. The iron fortificants were isotopically labelled with (57) Fe for the reference FeSO4 or (58) Fe for the tested fortificants, and iron absorption was quantified based on erythrocyte incorporation of the iron isotopes 14 days after feeding. The relative bioavailability of FAC and of the FeSO4  + NaFeEDTA was obtained by comparing their iron absorption with that of FeSO4 . Mean fractional iron absorption was 5.8% [±standard error (SE) 1.9] from FAC and 10.3% (±SE 1.9) from FeSO4  + NaFeEDTA. The relative bioavailability of FAC was 83% (P = 0.02). The relative bioavailability of FeSO4  + NaFeEDTA was 145% (P = 0.001). Iron absorption from the rice containing FAC or FeSO4  + NaFeEDTA was sufficiently high to be used in its formulation, although iron absorption from FeSO4  + NaFeEDTA was significantly higher (P < 0.00001).

  14. Comparison of inhibitory mold agar to Sabouraud dextrose agar as a primary medium for isolation of fungi.

    PubMed

    Scognamiglio, Theresa; Zinchuk, Riva; Gumpeni, Pramod; Larone, Davise H

    2010-05-01

    Clinical specimens cultured on two selective fungal media, inhibitory mold agar (IMA) and Sabouraud dextrose agar (SDA), were compared with respect to recovery of fungi. Of the 840 fungal isolates recovered, 69.3% grew on both IMA and SDA; 24.9% grew only on IMA; and 5.8% grew only on SDA, showing that IMA is superior (P=0.003).

  15. FO-SPR based dextrose sensor using Ag/ZnO nanorods/GOx for insulinoma detection.

    PubMed

    Usha, Sruthi P; Shrivastav, Anand M; Gupta, Banshi D

    2016-11-15

    In this piece of work, a fiber optic sensor has been fabricated and characterized using surface plasmon resonance for dextrose sensing. The concentration range used in this study is for diagnosing the cases of hypoglycaemia especially in suppression tests of insulinoma. Insulinoma is a medical case in which the person is recognized being hypoglycaemic with the blood dextrose level falling down to 2.2mM or less. Thus, the sensor has been characterized for the dextrose concentration range of 0 mM-10mM including the cases of normal blood dextrose range. Coatings of silver layer and zinc oxide nanorods have been carried out on the bare core fiber with a dual role of zinc oxide followed by immobilization of glucose oxidase. A three stage optimization procedure has been adopted for the best performance of the sensor. Absorbance spectra have been plotted and peak absorbance wavelengths have been extracted for each concentration chosen along with the sensitivities. The results have been made conclusive with control experiments. The probe has also been tested on sample having blood serum to check the reliability of the sensor. The sensor shows better selectivity and response time along with its real time applications, online monitoring, remote sensing and reusability.

  16. Genome-wide identification of citrus ATP-citrate lyase genes and their transcript analysis in fruits reveals their possible role in citrate utilization.

    PubMed

    Hu, Xiao-Mei; Shi, Cai-Yun; Liu, Xiao; Jin, Long-Fei; Liu, Yong-Zhong; Peng, Shu-Ang

    2015-02-01

    ATP-citrate lyase (ACL, EC4.1.3.8) catalyzes citrate to oxaloacetate and acetyl-CoA in the cell cytosol, and has important roles in normal plant growth and in the biosynthesis of some secondary metabolites. We identified three ACL genes, CitACLα1, CitACLα2, and CitACLβ1, in the citrus genome database. Both CitACLα1 and CitACLα2 encode putative ACL α subunits with 82.5 % amino acid identity, whereas CitACLβ1 encodes a putative ACL β subunit. Gene structure analysis showed that CitACLα1 and CitACLα2 had 12 exons and 11 introns, and CitACLβ1 had 16 exons and 15 introns. CitACLα1 and CitACLβ1 were predominantly expressed in flower, and CitACLα2 was predominantly expressed in stem and fibrous roots. As fruits ripen, the transcript levels of CitACLα1, CitACLβ1, and/or CitACLα2 in cultivars 'Niuher' and 'Owari' increased, accompanied by significant decreases in citrate content, while their transcript levels decreased significantly in 'Egan No. 1' and 'Iyokan', although citrate content also decreased. In 'HB pummelo', in which acid content increased as fruit ripened, and in acid-free pummelo, transcript levels of CitACLα2, CitACLβ1, and/or CitACLα1 increased. Moreover, mild drought stress and ABA treatment significantly increased citrate contents in fruits. Transcript levels of the three genes were significantly reduced by mild drought stress, and the transcript level of only CitACLβ1 was significantly reduced by ABA treatment. Taken together, these data indicate that the effects of ACL on citrate use during fruit ripening depends on the cultivar, and the reduction in ACL gene expression may be attributed to citrate increases under mild drought stress or ABA treatment.

  17. Generation of circularly permuted fluorescent-protein-based indicators for in vitro and in vivo detection of citrate.

    PubMed

    Honda, Yuki; Kirimura, Kohtaro

    2013-01-01

    Indicators for citrate, particularly those applicable to its in vivo detection and quantitation, have attracted much interest in both biochemical studies and industrial applications since citrate is a key metabolic intermediate playing important roles in living cells. We generated novel fluorescence indicators for citrate by fusing the circularly permuted fluorescent protein (cpFP) and the periplasmic domain of the bacterial histidine kinase CitA, which can bind to citrate with high specificity. The ratiometric fluorescent signal change was observed with one of these cpFP-based indicators, named CF98: upon addition of citrate, the excitation peak at 504 nm increased proportionally to the decrease in the peak at 413 nm, suitable for build-in quantitative estimation of the binding compound. We confirmed that CF98 can be used for detecting citrate in vitro at millimolar levels in the range of 0.1 to 50 mM with high selectivity; even in the presence of other organic acids such as isocitrate and malate, the fluorescence intensity of CF98 remains unaffected. We finally demonstrated the in vivo applicability of CF98 to estimation of the intracellular citrate concentration in Escherichia coli co-expressing the genes encoding CF98 and the citrate carrier CitT. The novel indicator CF98 can be a specific and simple detection tool for citrate in vitro and a non-invasive tool for real-time estimation of intracellular concentrations of the compound in vivo.

  18. Citrate influences microbial Fe hydroxide reduction via a dissolution-disaggregation mechanism

    NASA Astrophysics Data System (ADS)

    Braunschweig, Juliane; Klier, Christine; Schröder, Christian; Händel, Matthias; Bosch, Julian; Totsche, Kai U.; Meckenstock, Rainer U.

    2014-08-01

    Microbial reduction of ferric iron is partly dependent on Fe hydroxide particle size: nanosized Fe hydroxides greatly exceed the bioavailability of their counterparts larger than 1 μm. Citrate as a low molecular weight organic acid can likewise stabilize colloidal suspensions against aggregation by electrostatic repulsion but also increase Fe bioavailability by enhancing Fe hydroxide solubility. The aim of this study was to see whether adsorption of citrate onto surfaces of large ferrihydrite aggregates results in the formation of a stable colloidal suspension by electrostatic repulsion and how this effect influences microbial Fe reduction. Furthermore, we wanted to discriminate between citrate-mediated colloid stabilization out of larger aggregates and ferrihydrite dissolution and their influence on microbial Fe hydroxide reduction. Dissolution kinetics of ferrihydrite aggregates induced by different concentrations of citrate and humic acids were compared to microbial reduction kinetics with Geobacter sulfurreducens. Dynamic light scattering results showed the formation of a stable colloidal suspension and colloids with hydrodynamic diameters of 69 (±37) to 165 (± 65) nm for molar citrate:Fe ratios of 0.1 to 0.5 and partial dissolution of ferrihydrite at citrate:Fe ratios ⩾ 0.1. No dissolution or colloid stabilization was detected in the presence of humic acids. Adsorption of citrate, necessary for dissolution, reversed the surface charge and led to electrostatic repulsion between sub-aggregates of ferrihydrite and colloid stabilization when the citrate:Fe ratio was above a critical value (⩽ 0.1). Lower ratios resulted in stronger ferrihydrite aggregation instead of formation of a stable colloidal suspension, owing to neutralization of the positive surface charge. At the same time, microbial ferrihydrite reduction increased from 0.029 to 0.184 mM h-1 indicating that colloids stabilized by citrate addition enhanced microbial Fe reduction. Modelling of

  19. Renal tissue citrate: independence from citrate utilization, reabsorption, and pH.

    PubMed

    Anaizi, N H; Cohen, J J; Black, A J; Wertheim, S J

    1986-09-01

    During alkalosis in vivo, renal tissue [citrate] [( citrate]t) increases and citrate reabsorption (Tcit) and utilization (Qcit) simultaneously decrease. The decrease in Qcit is interpreted to cause the increased [citrate]t, which in turn decreases Tcit X Renal citrate handling and [citrate]t could be regulated by other mechanisms, since alkalosis changes [substrate] and [H+] in extracellular (ECF) and intracellular (ICF) fluid. Also, since high plasma [citrate] decreases ionized [Ca2+] (Cai), it is not possible to determine in vivo whether there is a maximum for Tcit or Qcit and whether change in extracellular fluid (delta ECF) pH affects these maxima. We perfused the substrate-limited isolated rat kidney for either 110 (n = 36) or 50 min (n = 44) at pH 7.2, 7.4, or 7.6; pH was changed by varying [HCO3-]; Cai was held constant at approximately 2.5 meq/liter. When citrate was the only substrate available in a Krebs-Ringer-HCO3 perfusate containing 6% substrate-free albumin, both Qcit and Tcit had maximal rates: Qcit much greater than Tcit; at pH 7.6, Qcit and Tcit were significantly reduced below their values at pH 7.2 or 7.4. In contrast to in vivo observations, [citrate]t was not significantly increased at high ECF pH. To test whether [citrate]t in the perfused kidney can increase in alkalosis, 11 additional perfusions were done in the presence of glucose plus lactate plus malate but without added citrate: [citrate]t = 0.6 mumol X g-1 at pH 7.6 and 0.3 mumol X g-1 at pH 7.2 (P less than 0.01); no citrate was detectable in the perfusate, and urinary citrate excretion was negligible. Thus, in the isolated rat kidney, an increase in [citrate]t occurred in alkalosis and was derived from precursors and not from citrate in the ECF. Overall, when only citrate was available to the isolated kidney during alkalosis, a significant rise in [citrate]t did not occur, although Vmax for Tcit and Qcit decreased. These effects of alkalosis on Tcit are consistent with observations

  20. Continuous venovenous hemodialysis with regional citrate anticoagulation in patients with liver failure: a prospective observational study

    PubMed Central

    2012-01-01

    Introduction Liver failure patients might be at risk for citrate accumulation during continuous venovenous hemodialysis (CVVHD) with regional citrate anticoagulation. The aim of this study was to investigate the predictive capability of baseline liver function parameters regarding citrate accumulation, expressed as an increase in the calcium total/calcium ionized (Catot/Caion) ratio ≥2.5, and to describe the feasibility of citrate CVVHD in liver failure patients. Methods We conducted a prospective observational study in medical ICU patients treated in a German university hospital. We performed 43 CVVHD runs using citrate for regional anticoagulation in 28 critically ill patients with decompensated liver cirrhosis or acute liver failure (maximum of two CVVHD runs per patient). Liver function was characterized before CVVHD using laboratory parameters, calculation of Child-Pugh and Model of End-stage Liver Disease scores, and determination of the plasma disappearance rate of indocyanine green. In addition to blood gas analysis, we measured total calcium and citrate in serum at baseline and after definitive time points for each CVVHD run. Results Accumulation of citrate in serum correlated with an increase in the Catot/Caion ratio. Although the critical upper threshold of Catot/Caion ratio ≥2.5 was exceeded 10 times in seven different CVVHD runs, equalization of initial metabolic acidosis was possible without major disturbances of acid-base and electrolyte status. Standard laboratory liver function parameters showed poor predictive capabilities regarding citrate accumulation in terms of an elevated Catot/Caion ratio ≥2.5. In contrast, serum lactate ≥3.4 mmol/l and prothrombin time ≤26% predicted an increase in the Catot/Caion ratio ≥2.5 with high sensitivity (86% for both lactate and prothrombin time) and specificity (86% for lactate, 92% for prothrombin time). Conclusions Despite substantial accumulation of citrate in serum, CVVHD with regional citrate

  1. Outcome at two years after dextrose gel treatment for neonatal hypoglycemia; Follow up of a randomized trial

    PubMed Central

    Harris, Deborah L; Alsweiler, Jane M; Ansell, Judith M; Gamble, Greg D; Thompson, Ben; Wouldes, Trecia A; Yu, Tzu-Ying; Harding, Jane E

    2015-01-01

    Objective To determine neurodevelopmental outcome at two years’ corrected age in children randomized to treatment with dextrose gel or placebo for hypoglycemia soon after birth (The Sugar Babies Study). Study design This was a follow-up study of 184 children who had been hypoglycemic (< 2.6mM [45 mg/dL]) in the first 48 hours and randomized to either dextrose (90/118, 76%) or placebo gel (94/119, 79%). Assessments were performed at Kahikatea House, Hamilton, New Zealand, and included neurological function and general health (Pediatrician assessed), cognitive, language, behaviour and motor skills (Bayley-III), executive function (clinical assessment and BRIEF-P), and vision (clinical examination and global motion perception). Co-primary outcomes were neurosensory impairment (cognitive, language or motor score below −1 SD or cerebral palsy or blind or deaf) and processing difficulty (executive function or global motion perception worse than 1.5 SD from the mean). Statistical tests were two sided with 5% significance level. Results Mean (±SD) birth weight was 3093 ± 803 g and mean gestation was 37.7 ±1.6 weeks. Sixty-six children (36%) had neurosensory impairment (1 severe, 6 moderate, 59 mild) with similar rates in both groups (dextrose 38% vs. placebo 34%, RR 1.11, 95% CI 0.75–1.63). Processing difficulty was also similar between groups (dextrose 10% vs. placebo 18%, RR 0.52, 95% CI 0.23–1.15). Conclusions Dextrose gel is safe for treatment of neonatal hypoglycemia, but neurosensory impairment is common amongst these children. PMID:26613985

  2. [Development of identification method for isopropyl citrate].

    PubMed

    Furusho, Noriko; Ohtsuki, Takashi; Tatebe-Sasaki, Chiye; Kubota, Hiroki; Sato, Kyoko; Akiyama, Hiroshi

    2014-01-01

    In Japan's Specification and Standards for Food Additive, 8th edition, two identification tests involving isopropyl citrate for detecting isopropyl alcohol and citrate are stipulated. However, these identification tests use mercury compound, which is toxic, or require a time-consuming pretreatment process. To solve these problems, an identification test method using GC-FID for detecting isopropyl alcohol was developed. In this test, a good linearity was observed in the range of 0.1-40 mg/mL of isopropyl alcohol. While investigating the pretreatment process, we found that isopropyl alcohol could be detected using GC-FID in the distillation step only, without involving any reflux step. The study also showed that the citrate moiety of isopropyl citrate was identified using the solution remaining after conducting the distillation of isopropyl alcohol. The developed identification tests for isopropyl citrate are simple and use no toxic materials.

  3. Citrate anticoagulation: Are blood donors donating bone?

    PubMed

    Bialkowski, Walter; Bruhn, Roberta; Edgren, Gustaf; Papanek, Paula

    2016-10-01

    An estimated 2.4 million volunteer apheresis blood donation procedures were performed in the United States in 2010, and increases in the proportion of transfused blood products derived from apheresis blood collections have been consistently reported. Anticoagulation is required during apheresis and is achieved with citrate. Donor exposure to citrate causes an acute physiological response to maintain serum mineral homeostasis. Some data are available on the sequelae of this acute response in the days and weeks following exposure, raising questions about bone mineral density in regular apheresis donors. New research is emerging that addresses the potential long-term health outcomes of repeated citrate exposure. This article reviews the acute physiological response to citrate anticoagulation in volunteer blood donors, presents contrasting perspectives on the potential effects of citrate exposure on bone density, and identifies key knowledge gaps in our understanding of long-term health outcomes in apheresis donors. J. Clin. Apheresis 31:459-463, 2016. © 2015 Wiley Periodicals, Inc.

  4. Incompatibility of Contrast Medium and Trisodium Citrate

    SciTech Connect

    Delcour, Christian Bruninx, Guy

    2013-02-15

    To test the compatibility of trisodium citrate, a catheter lock solution, with iodinated contrast medium. Iohexol, iobitridol, iodixanol, ioxaglate, ioxithalamate, iomeprol, and iopromide were tested. In all tests, 2 ml of contrast medium were mixed with 2 ml of trisodium citrate solution. Iodixanol and ioxaglate provoked a highly viscous gluelike precipitation when mixed with trisodium citrate. A brief transient precipitate was observed with iohexol, iomeprol, and ioxithalamate. Permanent precipitation occurred with iobitridol and iopromide. One must be aware of the potential for precipitation when contrast medium is mixed with trisodium citrate solution. Before trisodium citrate solution is injected, the catheter should be thoroughly flushed with saline if a contrast medium has previously been injected through it.

  5. Citrate-enhanced release of arsenic during pyrite oxidation at circumneutral conditions.

    PubMed

    Zhang, Peng; Yao, Weiyu; Yuan, Songhu

    2017-02-01

    The release of arsenic (As) from the oxidation of As-rich pyrite is an important source of the high arsenic in groundwater. As a widespread low-molecular-weight organic acid, citrate plays an important role on the cycling of Fe(II)/Fe(III) through complexation in circumneutral subsurface environments, while the influence of citrate on the release of As from the oxidation of As-rich pyrite is poorly understood. In this study, As was loaded onto pyrite particles under anoxic conditions, and its release was investigated in the presence of 0-1 mM citrate at pH 7.4 under oxic conditions. As-loaded pyrite suspension was prepared by the equilibrium of 2.67 μM As(III) in 10 g/L pyrite under anoxic conditions with the decrease in dissolved As(III) concentration to 1 μM. The suspension was subsequently exposed to air for oxygenation. In the absence of citrate, the oxygenation decreased the partitioning of As in the solution because of the re-adsorption of aqueous As by the in situ generated Fe(III) oxyhydroxides. However, with the increase in citrate concentration from 0.1 to 1 mM, the As partitioned in the solution increased from 0.3 to 2.67 μM. In the presence of 1 mM citrate, the As(III) was almost completely oxidized to As(V) during the oxygenation. The mechanisms of citrate-enhanced release of As were mainly attributed to the ligand exchange of citrate with As for pyrite surface sites, the competitive adsorption of citrate with As on Fe(III) oxyhydroxides and pyrite, and the partitioning of As on the newly formed Fe(III) colloids. This finding presents an overlooked mechanism of the release of pyrite-associated As under oxic and circumneutral conditions.

  6. Physiologically relevant divalent cations modulate citrate recognition by the McpS chemoreceptor.

    PubMed

    Lacal, Jesús; García-Fontana, Cristina; Callejo-García, Carla; Ramos, Juan-Luis; Krell, Tino

    2011-01-01

    The McpS chemoreceptor of Pseudomonas putida KT2440 recognizes six different tricarboxylic acid (TCA) cycle intermediates. However, the magnitude of the chemotactic response towards these compounds differs largely, which has led to distinguish between strong attractants (malate, succinate, fumarate, oxaloacetate) and weak attractants (citrate, isocitrate). Citrate is abundantly present in plant tissues and root exudates and can serve as the only carbon source for growth. Citrate is known to form complexes with divalent cations which are also abundantly present in natural habitats of this bacterium. We have used isothermal titration calorimetry to study the formation of citrate-metal ion complexes. In all cases binding was entropy driven but significant differences in affinity were observed ranging from K(D)=157 µM (for Mg(2+)) to 3 µM (for Ni(2+)). Complex formation occurred over a range of pH and ionic strength. The ligand binding domain of McpS (McpS-LBD) was found to bind free citrate, but not complexes with physiologically relevant Mg(2+) and Ca(2+). In contrast, complexes with divalent cations which are present as trace elements (Co(2+), Cd(2+) and Ni(2+)) were recognized by McpS-LBD. This discrimination differs from other citrate sensing proteins. These results are discussed in the context of the three dimensional structure of free citrate and its complex with Mg(2+). Chemotaxis assays using P. putida revealed that taxis towards the strong attractant malate is strongly reduced in the presence of free citrate. However, this reduction is much less important in the presence of citrate-Mg(2+) complexes. The physiological relevance of these findings is discussed.

  7. Stability-Indicating UPLC Method for Tramadol HCl Impurities in the Tramadol Injection after Dilution by Infusion Fluids (5% Dextrose and 0.9% Sodium Chloride).

    PubMed

    Binnor, Anil K; Mukkanti, Khagga; Suryanarayana, Mulukutla V; Roy, Sunilendu B

    2013-01-01

    A novel, rapid, and sensitive ultra-performance liquid chromatography (UPLC) method has been developed and validated as per ICH guidelines for the determination of tramadol HCl impurities in the tramadol HCl injection after reconstitution by infusion fluids (5% dextrose and 0.9% sodium chloride). The tramadol HCl injection is for the treatment of patients with moderate-to-severe pain. The stability of the reconstituted solution is critical before intravenous injection. The literature search resulted in few published articles on assays of tramadol in infusion fluids by conventional HPLC. No attempts have yet been made to determine the impurities in infusion fluids, as the concentration of tramadol after reconstitution is extremely low (0.4 mg/mL) and that of impurities is even lower. The proposed method is novel as it allows the quantitation of the impurities of tramadol HCl and is based on modern chromatographic techniques like UPLC. The method was developed using the Waters Acquity BEH C18 column with a mobile phase consisting of a gradient mixture of solvent A (trifluroacetic acid buffer) and solvent B (methanol: acetonitrile). The model stability study was designed by diluting the tramadol HCl injection in the 5% dextrose injection and 0.9% sodium chloride injection. Each mixture was kept under storage at room temperature (25 ± 2°C) for testing at initial, 2, 4, 8, 12, 18 & 24 hours. The validation study illustrates that the proposed method is suitable for the determination of tramadol and its impurities. The proposed method makes use of the LC-MS-compatible mobile phase. It can be useful for the determination of tramadol HCl and its impurities in plasma samples and other pharmaceutical dosage forms.

  8. Films based on neutralized chitosan citrate as innovative composition for cosmetic application.

    PubMed

    Libio, Illen C; Demori, Renan; Ferrão, Marco F; Lionzo, Maria I Z; da Silveira, Nádya P

    2016-10-01

    In this work, citrate and acetate buffers, were investigated as neutralizers to chitosan salts in order to provide biocompatible and stable films. To choose the appropriate film composition for this study, neutralized chitosan citrate and acetate films, with and without the plasticizer glycerol, were prepared and characterized by thickness, moisture content, degree of swelling, total soluble matter in acid medium, simultaneous thermal analysis and differential scanning calorimetry. Chitosan films neutralized in citrate buffer showed greater physical integrity resulted from greater thicknesses, lower moisture absorbance, lower tendency to solubility in the acid medium, and better swelling capacities. According to thermal analyses, these films had higher interaction with water which is considered an important feature for cosmetic application. Since the composition prepared in citrate buffer without glycerol was considered to present better physical integrity, it was applied to investigate hyaluronic acid release in a skin model. Skins treated with those films, with or without hyaluronic acid, show stratum corneum desquamation and hydration within 10min. The results suggest that the neutralized chitosan citrate film prepared without glycerol promotes a cosmetic effect for skin exfoliation in the presence or absence of hyaluronic acid.

  9. Artificial citrate operon confers mineral phosphate solubilization ability to diverse fluorescent pseudomonads.

    PubMed

    Adhikary, Hemanta; Sanghavi, Paulomi B; Macwan, Silviya R; Archana, Gattupalli; Naresh Kumar, G

    2014-01-01

    Citric acid is a strong acid with good cation chelating ability and can be very efficient in solubilizing mineral phosphates. Only a few phosphate solubilizing bacteria and fungi are known to secrete citric acids. In this work, we incorporated artificial citrate operon containing NADH insensitive citrate synthase (gltA1) and citrate transporter (citC) genes into the genome of six-plant growth promoting P. fluorescens strains viz., PfO-1, Pf5, CHAO1, P109, ATCC13525 and Fp315 using MiniTn7 transposon gene delivery system. Comprehensive biochemical characterization of the genomic integrants and their comparison with plasmid transformants of the same operon in M9 minimal medium reveals the highest amount of ∼7.6±0.41 mM citric and 29.95±2.8 mM gluconic acid secretion along with ∼43.2±3.24 mM intracellular citrate without affecting the growth of these P. fluorescens strains. All genomic integrants showed enhanced citric and gluconic acid secretion on Tris-Cl rock phosphate (TRP) buffered medium, which was sufficient to release 200-1000 µM Pi in TRP medium. This study demonstrates that MPS ability could be achieved in natural fluorescent pseudomonads by incorporation of artificial citrate operon not only as plasmid but also by genomic integration.

  10. Study on the Antimicrobial Properties of Citrate-Based Biodegradable Polymers

    PubMed Central

    Su, Lee-Chun; Xie, Zhiwei; Zhang, Yi; Nguyen, Kytai Truong; Yang, Jian

    2014-01-01

    Citrate-based polymers possess unique advantages for various biomedical applications since citric acid is a natural metabolism product, which is biocompatible and antimicrobial. In polymer synthesis, citric acid also provides multiple functional groups to control the crosslinking of polymers and active binding sites for further conjugation of biomolecules. Our group recently developed a number of citrate-based polymers for various biomedical applications by taking advantage of their controllable chemical, mechanical, and biological characteristics. In this study, various citric acid derived biodegradable polymers were synthesized and investigated for their physicochemical and antimicrobial properties. Results indicate that citric acid derived polymers reduced bacterial proliferation to different degrees based on their chemical composition. Among the studied polymers, poly(octamethylene citrate) showed ~70–80% suppression to microbe proliferation, owing to its relatively higher ratio of citric acid contents. Crosslinked urethane-doped polyester elastomers and biodegradable photoluminescent polymers also exhibited significant bacteria reduction of ~20 and ~50% for Staphylococcus aureus and Escherichia coli, respectively. Thus, the intrinsic antibacterial properties in citrate-based polymers enable them to inhibit bacteria growth without incorporation of antibiotics, silver nanoparticles, and other traditional bacteria-killing agents suggesting that the citrate-based polymers are unique beneficial materials for wound dressing, tissue engineering, and other potential medical applications where antimicrobial property is desired. PMID:25023605

  11. Study on the Antimicrobial Properties of Citrate-Based Biodegradable Polymers.

    PubMed

    Su, Lee-Chun; Xie, Zhiwei; Zhang, Yi; Nguyen, Kytai Truong; Yang, Jian

    2014-01-01

    Citrate-based polymers possess unique advantages for various biomedical applications since citric acid is a natural metabolism product, which is biocompatible and antimicrobial. In polymer synthesis, citric acid also provides multiple functional groups to control the crosslinking of polymers and active binding sites for further conjugation of biomolecules. Our group recently developed a number of citrate-based polymers for various biomedical applications by taking advantage of their controllable chemical, mechanical, and biological characteristics. In this study, various citric acid derived biodegradable polymers were synthesized and investigated for their physicochemical and antimicrobial properties. Results indicate that citric acid derived polymers reduced bacterial proliferation to different degrees based on their chemical composition. Among the studied polymers, poly(octamethylene citrate) showed ~70-80% suppression to microbe proliferation, owing to its relatively higher ratio of citric acid contents. Crosslinked urethane-doped polyester elastomers and biodegradable photoluminescent polymers also exhibited significant bacteria reduction of ~20 and ~50% for Staphylococcus aureus and Escherichia coli, respectively. Thus, the intrinsic antibacterial properties in citrate-based polymers enable them to inhibit bacteria growth without incorporation of antibiotics, silver nanoparticles, and other traditional bacteria-killing agents suggesting that the citrate-based polymers are unique beneficial materials for wound dressing, tissue engineering, and other potential medical applications where antimicrobial property is desired.

  12. Myocardial citrate metabolism in control subjects and patients with coronary artery disease.

    PubMed

    Nielsen, T T; Henningsen, P; Bagger, J P; Thomsen, P E; Eyjolfsson, K

    1980-10-01

    A significant release of citrate across the myocardium was demonstrated in twenty-two patients with coronary artery disease (CAD) and in ten control subjects in fasting resting state. In both groups, increasingly negative arterio-coronary sinus (A-Cs) plasma citrate differences correlated positively to arterial plasma free fatty acid (FFA)concentrations and negatively to (A-Cs) differences of plasma glucose. This supports the hypothesis that a citrate inhibition of glycolysis at the site of phosphofructokinase is of regulatory importance for myocardial glucose metabolism, and suggests that FFA supress glucose utilization by the heart in many by this mechanism. The capacity of plasma FFA to increase myocardial citrate release was significantly higher in controls than in patients with CAD, and was found to be positively related to myocardial capacity of oxygen consumption as estimated from the product of heart rate and systolic blood pressure during an exercise tolerance test.

  13. Overexpression of Citrus junos mitochondrial citrate synthase gene in Nicotiana benthamiana confers aluminum tolerance.

    PubMed

    Deng, Wei; Luo, Keming; Li, Zhengguo; Yang, Yingwu; Hu, Nan; Wu, Yu

    2009-07-01

    Aluminum (Al) toxicity is one of the major factors that limit plant growth in acid soils. Al-induced release of organic acids into rhizosphere from the root apex has been identified as a major Al-tolerance mechanism in many plant species. In this study, Al tolerance of Yuzu (Citrus Junos Sieb. ex Tanaka) was tested on the basis of root elongation and the results demonstrated that Yuzu was Al tolerant compared with other plant species. Exposure to Al triggered the exudation of citrate from the Yuzu root. Thus, the mechanism of Al tolerance in Yuzu involved an Al-inducible increase in citrate release. Aluminum also elicited an increase of citrate content and increased the expression level of mitochondrial citrate synthase (CjCS) gene and enzyme activity in Yuzu. The CjCS gene was cloned from Yuzu and overexpressed in Nicotiana benthamiana using Agrobacterium tumefaciens-mediated methods. Increased expression level of the CjCS gene and enhanced enzyme activity were observed in transgenic plants compared with the wild-type plants. Root growth experiments showed that transgenic plants have enhanced levels of Al tolerance. The transgenic Nicotiana plants showed increased levels of citrate in roots compared to wild-type plants. The exudation of citrate from roots of the transgenic plants significantly increased when exposed to Al. The results with transgenic plants suggest that overexpression of mitochondrial CS can be a useful tool to achieve Al tolerance.

  14. Citrate, a Ubiquitous Key Metabolite with Regulatory Function in the CNS.

    PubMed

    Westergaard, Niels; Waagepetersen, Helle S; Belhage, Bo; Schousboe, Arne

    2017-01-05

    Citrate is key constituent of the tricarboxylic acid (TCA) cycle, serves as substrate for fatty acid and sterol biosynthesis, and functions as a key regulator of intermediary energy metabolism. Ursula Sonnewald had initiated studies using for the first time both proton- and (13)C-NMR to investigate metabolic processes in cultured neurons and astrocytes resulting in the important observation that citrate was specifically synthesized in and released from astrocytes in large amounts which is in keeping with the high concentration found in the CSF. The aim of this review is to highlight the possible roles of citrate in physiological and pathophysiological processes in the CNS. An interesting feature of citrate is its ability to chelate Ca(2+), Mg(2+) and Zn(2+)and thereby playing a pivotal role as an endogenous modulator of glutamate receptors and in particular the NMDA subtypes of these receptors in the CNS. Besides its presence in cerebrospinal fluid (CSF) citrate is also found in high amounts in prostate fluid reaching concentrations as high as 180 mM and here Zn(2+) seems also to play an important role, which makes prostate cells interesting for comparison of features of citrate and Zn(2+) between these cells and cells in the CNS.

  15. [Butamyrate citrate in cough controlling].

    PubMed

    Płusa, Tadeusz

    2013-12-01

    The cough as one of the main symptoms of respiratory infections in the most cases is carried out in children and adults using preparations without a prescription (OTC--over-the-counter) and cold medications (CCMs). Their efficacy and safety have not been fully confirmed. In turn, the administration of drugs that inhibit cough by acting on the central nervous system requires adherence to dosage. Codeine as the main standard of the cough suppressants is not always effective. Used for many years butamyrate citrate is highly effective and complete safety. The number and quality of the side effects after application of this preparation is small and is not limited especially in pediatrics. Conducted research on new drugs that inhibit cough are very promising.

  16. Determination of dextrose equivalent value and number average molecular weight of maltodextrin by osmometry.

    PubMed

    Rong, Y; Sillick, M; Gregson, C M

    2009-01-01

    Dextrose equivalent (DE) value is the most common parameter used to characterize the molecular weight of maltodextrins. Its theoretical value is inversely proportional to number average molecular weight (M(n)), providing a theoretical basis for correlations with physical properties important to food manufacturing, such as: hygroscopicity, the glass transition temperature, and colligative properties. The use of freezing point osmometry to measure DE and M(n) was assessed. Measurements were made on a homologous series of malto-oligomers as well as a variety of commercially available maltodextrin products with DE values ranging from 5 to 18. Results on malto-oligomer samples confirmed that freezing point osmometry provided a linear response with number average molecular weight. However, noncarbohydrate species in some commercial maltodextrin products were found to be in high enough concentration to interfere appreciably with DE measurement. Energy dispersive spectroscopy showed that sodium and chloride were the major ions present in most commercial samples. Osmolality was successfully corrected using conductivity measurements to estimate ion concentrations. The conductivity correction factor appeared to be dependent on the concentration of maltodextrin. Equations were developed to calculate corrected values of DE and M(n) based on measurements of osmolality, conductivity, and maltodextrin concentration. This study builds upon previously reported results through the identification of the major interfering ions and provides an osmolality correction factor that successfully accounts for the influence of maltodextrin concentration on the conductivity measurement. The resulting technique was found to be rapid, robust, and required no reagents.

  17. Photodegradation of uranium-citrate complex with uranium recovery

    SciTech Connect

    Dodge, C.J.; Francis, A.J. )

    1994-07-01

    Upon exposure to visible light, uranyl citrate complex showed photodegradation of citric acid to acetic acid and carbon dioxide, with the precipitation of uranium as uranium trioxide (UO[sub 3][center dot]2H[sub 2]O). The initial pH and presence of oxygen affected the rate and extent of photochemical degradation of the complex, the formation of intermediate organic degradation products, and uranium speciation. Under aerobic conditions at pH 3.5, acetic, acetoacetic, 3-oxoglutaric, and malonic acids and acetone were detected; at pH 6.0, 3-oxoglutaric and acetic acids were present. The uranyl U(VI) ion was reduced to uranous U(IV) ion and was subsequently reoxidized to the hexavalent form and precipitated out of solution as uranium trioxide. Uranium trioxide precipitate was insoluble at near-neutral pH and was soluble in acidic pH (<4.1). Under anaerobic conditions, the uranyl citrate complex showed only partial (57%) degradation, and uranium was present in the reduced form as U(IV). Excess citric acid retarded the precipitation of uranium. 26 refs., 9 figs., 1 tab.

  18. A citrate-binding site in calmodulin.

    PubMed

    Neufeld, T; Eisenstein, M; Muszkat, K A; Fleminger, G

    1998-01-01

    Calmodulin (CaM) is a major Ca2+ messenger which, upon Ca2+ activation, binds and activates a number of target enzymes involved in crucial cellular processes. The dependence on Ca2+ ion concentration suggests that CaM activation may be modulated by low-affinity Ca2+ chelators. The effect on CaM structure and function of citrate ion, a Ca2+ chelator commonly found in the cytosol and the mitochondria, was therefore investigated. A series of structural and biochemical methods, including tryptic mapping, immunological recognition by specific monoclonal antibodies, CIDNP-NMR, binding to specific ligands and association with radiolabeled citrate, showed that citrate induces conformational modifications in CaM which affect the shape and activity of the protein. These changes were shown to be associated with the C-terminal lobe of the molecule and involve actual binding of citrate to CaM. Analyzing X-ray structures of several citrate-binding proteins by computerized molecular graphics enabled us to identify a putative citrate-binding site (CBS) on the CaM molecule around residues Arg106-His107. Owing to the tight proximity of this site to the third Ca(2+)-binding loop of CaM, binding of citrate is presumably translated into changes in Ca2+ binding to site III (and indirectly to site IV). These changes apparently affect the structural and biochemical properties of the conformation-sensitive protein.

  19. Citrate bridges between mineral platelets in bone.

    PubMed

    Davies, Erika; Müller, Karin H; Wong, Wai Ching; Pickard, Chris J; Reid, David G; Skepper, Jeremy N; Duer, Melinda J

    2014-04-08

    We provide evidence that citrate anions bridge between mineral platelets in bone and hypothesize that their presence acts to maintain separate platelets with disordered regions between them rather than gradual transformations into larger, more ordered blocks of mineral. To assess this hypothesis, we take as a model for a citrate bridging between layers of calcium phosphate mineral a double salt octacalcium phosphate citrate (OCP-citrate). We use a combination of multinuclear solid-state NMR spectroscopy, powder X-ray diffraction, and first principles electronic structure calculations to propose a quantitative structure for this material, in which citrate anions reside in a hydrated layer, bridging between apatitic layers. To assess the relevance of such a structure in native bone mineral, we present for the first time, to our knowledge, (17)O NMR data on bone and compare them with (17)O NMR data for OCP-citrate and other calcium phosphate minerals relevant to bone. The proposed structural model that we deduce from this work for bone mineral is a layered structure with thin apatitic platelets sandwiched between OCP-citrate-like hydrated layers. Such a structure can explain a number of known structural features of bone mineral: the thin, plate-like morphology of mature bone mineral crystals, the presence of significant quantities of strongly bound water molecules, and the relatively high concentration of hydrogen phosphate as well as the maintenance of a disordered region between mineral platelets.

  20. Bright luminescence of Vibrio fischeri aconitase mutants reveals a connection between citrate and the Gac/Csr regulatory system.

    PubMed

    Septer, Alecia N; Bose, Jeffrey L; Lipzen, Anna; Martin, Joel; Whistler, Cheryl; Stabb, Eric V

    2015-01-01

    The Gac/Csr regulatory system is conserved throughout the γ-proteobacteria and controls key pathways in central carbon metabolism, quorum sensing, biofilm formation and virulence in important plant and animal pathogens. Here we show that elevated intracellular citrate levels in a Vibrio fischeri aconitase mutant correlate with activation of the Gac/Csr cascade and induction of bright luminescence. Spontaneous or directed mutations in the gene that encodes citrate synthase reversed the bright luminescence of aconitase mutants, eliminated their citrate accumulation and reversed their elevated expression of CsrB. Our data elucidate a correlative link between central metabolic and regulatory pathways, and they suggest that the Gac system senses a blockage at the aconitase step of the tricarboxylic acid cycle, either through elevated citrate levels or a secondary metabolic effect of citrate accumulation, and responds by modulating carbon flow and various functions associated with host colonization, including bioluminescence.

  1. Effect of intrauterine dextrose or antibiotic therapy on reproductive performance of lactating dairy cows diagnosed with clinical endometritis.

    PubMed

    Brick, T A; Schuenemann, G M; Bas, S; Daniels, J B; Pinto, C R; Rings, D M; Rajala-Schultz, P J

    2012-04-01

    The objectives of this study were to assess the responses to treatments (clinical cure and cow survival 14 d posttherapy) of cows with clinical endometritis (CE) that received intrauterine infusion of a hypertonic solution of 50% dextrose (DEX) or subcutaneous ceftiofur crystalline free acid (CCFA) and subsequent pregnancy per artificial insemination (P/AI) in cows with CE compared with cows without CE. Cows (n=760) from 2 dairy herds were screened for CE using vaginoscopy and measurement of cervix diameters [exam 1; 26±3 d in milk (DIM)]. Cows with vaginal discharge scores of 2 or 3 (scale 0-3) were stratified by parity and randomly allocated into 1 of 3 treatment groups: (1) intrauterine infusion (∼200 mL) of 50% DEX solution (n=79); (2) 6.6 mg/kg single-dose of subcutaneous administration of CCFA (n=75); or (3) untreated control animals (CON, n=83). Fourteen days posttherapy (at 40±3 DIM), cows with CE were re-examined (exam 2; 40±3 DIM) to assess the response to treatments. All cows were presynchronized with 2 injections of PGF(2α) given 14 d apart (starting at 26±3 DIM) followed by Ovsynch (OV; GnRH-7 d-PGF-56 h-GnRH 16 h-timed-AI) 12 to 14 d later. Cows displaying signs of standing estrus any time during the protocol were inseminated, whereas the remaining cows were subjected to timed AI 16 h after the second GnRH of OV. Pregnancy diagnosis was performed via transrectal ultrasonography at 39±3d post-AI followed by pregnancy reconfirmation 30 d after the first pregnancy diagnosis. Uterine swabs revealed that Arcanobacterium pyogenes and Escherichia coli were the most predominant bacteria isolated at the time of treatments. Mortality within 14 d posttherapy was not different among treatment groups. Cows with CE had greater cervical diameter at exam 1 and decreased P/AI compared with cows without CE. Treatment with CCFA or DEX increased the proportion of cows with clear vaginal discharge (score 0; clinical cure) 14 d posttherapy compared with CON cows

  2. 21 CFR 172.430 - Iron ammonium citrate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Iron ammonium citrate. 172.430 Section 172.430... CONSUMPTION Anticaking Agents § 172.430 Iron ammonium citrate. Iron ammonium citrate may be safely used in... human consumption so that the level of iron ammonium citrate does not exceed 25 parts per million...

  3. 21 CFR 172.430 - Iron ammonium citrate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Iron ammonium citrate. 172.430 Section 172.430... CONSUMPTION Anticaking Agents § 172.430 Iron ammonium citrate. Iron ammonium citrate may be safely used in... human consumption so that the level of iron ammonium citrate does not exceed 25 parts per million...

  4. 21 CFR 172.430 - Iron ammonium citrate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Iron ammonium citrate. 172.430 Section 172.430... CONSUMPTION Anticaking Agents § 172.430 Iron ammonium citrate. Iron ammonium citrate may be safely used in... human consumption so that the level of iron ammonium citrate does not exceed 25 parts per million...

  5. 21 CFR 172.430 - Iron ammonium citrate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Iron ammonium citrate. 172.430 Section 172.430 Food... Anticaking Agents § 172.430 Iron ammonium citrate. Iron ammonium citrate may be safely used in food in... consumption so that the level of iron ammonium citrate does not exceed 25 parts per million (0.0025...

  6. 21 CFR 573.560 - Iron ammonium citrate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Iron ammonium citrate. 573.560 Section 573.560... Additive Listing § 573.560 Iron ammonium citrate. Iron ammonium citrate may be safely used in animal feed... consumption so that the level of iron ammonium citrate does not exceed 25 parts per million (0.0025...

  7. Comparative effectiveness of dextrose prolotherapy versus control injections and exercise in the management of osteoarthritis pain: a systematic review and meta-analysis

    PubMed Central

    Hung, Chen-Yu; Hsiao, Ming-Yen; Chang, Ke-Vin; Han, Der-Sheng; Wang, Tyng-Guey

    2016-01-01

    Background Increasing evidence has supported the use of dextrose prolotherapy for patients with osteoarthritis. However, the real benefits may be affected by differences in injection protocols, comparative regimens, and evaluation scales. Methods PubMed and Scopus were searched from the earliest record until February 2016. One single-arm study and five randomized controlled trials were included, comprising 326 participants. We estimated the effect sizes of pain reduction before and after serial dextrose injections and compared the values between dextrose prolotherapy, comparative regimens, and exercise 6 months after the initial injection. Results Regarding the treatment arm using dextrose prolotherapy, the effect sizes compared with baseline were 0.65 (95% confidence interval [CI], 0.14–1.17), 0.84 (95% CI, 0.40–1.27), 0.85 (95% CI, 0.60–1.10), and 0.87 (95% CI, 0.53–1.21) after the first, second, third, and fourth or more injections, respectively. The overall effect of dextrose was better than control injections (effect size, 0.36; 95% CI, 0.10–0.63). Dextrose prolotherapy had a superior effect compared with local anesthesia (effect size, 0.38; 95% CI, 0.07–0.70) and exercise (effect size, 0.71; 95% CI, 0.30–1.11). There was an insignificant advantage of dextrose over corticosteroids (effect size, 0.31; 95% CI, –0.18 to 0.80) which was only estimated from one study. Conclusion Dextrose injections decreased pain in osteoarthritis patients but did not exhibit a positive dose–response relationship following serial injections. Dextrose prolotherapy was found to provide a better therapeutic effect than exercise, local anesthetics, and probably corticosteroids when patients were retested 6 months following the initial injection. PMID:27799816

  8. Citrate synthase encoded by the CIT2 gene of Saccharomyces cerevisiae is peroxisomal.

    PubMed Central

    Lewin, A S; Hines, V; Small, G M

    1990-01-01

    The product of the CIT2 gene has the tripeptide SKL at its carboxyl terminus. This amino acid sequence has been shown to act as a peroxisomal targeting signal in mammalian cells. We examined the subcellular site of this extramitochondrial citrate synthase. Cells of Saccharomyces cerevisiae were grown on oleate medium to induce peroxisome proliferation. A fraction containing membrane-enclosed vesicles and organelles was analyzed by sedimentation on density gradients. In wild-type cells, the major peak of citrate synthase activity was recovered in the mitochondrial fraction, but a second peak of activity cosedimented with peroxisomes. The peroxisomal activity, but not the mitochondrial activity, was inhibited by incubation at pH 8.1, a characteristic of the extramitochondrial citrate synthase encoded by the CIT2 gene. In a strain in which the CIT1 gene encoding mitochondrial citrate synthase had been disrupted, the major peak of citrate synthase activity was peroxisomal, and all of the activity was sensitive to incubation at pH 8.1. Yeast cells bearing a cit2 disruption were unable to mobilize stored lipids and did not form stable peroxisomes in oleate. We conclude that citrate synthase encoded by CIT2 is peroxisomal and participates in the glyoxylate cycle. Images PMID:2181273

  9. Synergistic iron reduction and citrate dissimilation by Shewanella alga and Aeromonas veronii

    PubMed

    Knight; Caccavo; Wudyka; Blakemore

    1996-10-17

    Two bacterial isolates from Great Bay Estuary, New Hampshire, in co-culture carried out anaerobic dissimilation of citric acid with Fe(III) as the terminal electron acceptor. Neither isolate oxidized citrate with Fe(III) anaerobically in axenic culture. The Fe(III) reducer, Shewanella alga strain BrY, did not grow anaerobically with citrate as an energy source. The citrate utilizer, Aeromonas veronii, did not reduce iron axenically with a variety of electron donors including citrate. The onset of iron reduction by the co-culture occurred after initiation of citrate dissimilation and just prior to initiation of growth by either organism (as measured by viable plate counts). Anaerobic culture growth rates and final cell densities of each bacterial strain were greater in co-culture than in axenic cultures. By 48 h of growth, the co-culture had consumed 27 mM citrate as compared with 12 mM dissimilated by the axenic culture of A. veronii. By 48 h the co-culture produced half as much formate (6 mM) and twice as much acetate (40 mM) as did A. veronii grown axenically (12 mM and 20 mM, respectively). Formate produced from citrate by A. veronii appeared to have supported growth and Fe(III) reduction by S. alga.Although not obligatory, nutrient coupling between these two organisms illustrates that fermentative (A. veronii-type) organisms can convert organic compounds such as citrate to those used as substrates by dissimilatory Fe(III) reducers, including S. alga. This synergism broadens the range of substrates available for iron reduction, stimulates the extent and rate of organic electron donor degradation (and that of iron reduction) and enhances the growth of each participant.

  10. Regulation of Renal Citrate Metabolism by Bicarbonate Ion and pH: Observations in Tissue Slices and Mitochondria*

    PubMed Central

    Simpson, David P.

    1967-01-01

    The effect of acid-base balance on the oxidation and utilization of citrate and other organic acids has been studied in tissue slices and isolated kidney mitochondria. The results show that: 1) With bicarbonate-buffered media, citrate oxidation and utilization are inhibited in slices of renal cortex and in kidney mitochondria when [HCO3-] and pH are increased within the physiologic range (pH 7.0 to 7.8; 10 to 60 μmoles HCO3- per ml). When phosphate or Tris buffers are used, no comparable effect on citrate oxidation occurs when pH is varied. 2) This effect is not demonstrable in heart or liver slices when a physiologic buffer is used. 3) α-Ketoglutarate utilization is inhibited in slices of renal cortex under similar conditions. Pyruvate and L-malate utilization are not inhibited in slices or mitochondria. 4) Citrate content in slices of renal cortex incubated with a high [HCO3-] is considerably greater than the concentration found with a low [HCO3-] in the medium. This effect is not duplicated by pH change in a nonbicarbonate buffer system. In mitochondria citrate content is also increased markedly at high bicarbonate concentrations. 5) The kinetic characteristics of the inhibition of citrate oxidation are those of a competitive type of inhibition. 6) When pH was varied with a constant [HCO3-] in the media, citrate oxidation was inhibited by increasing pH in slices of renal cortex but not in mitochondria. On the other hand, when [HCO3-] was increased without change in pH, no decrease in citrate oxidation occurred in slices, but a marked inhibitory effect was found when mitochondria were used. From a comparison of these results with those previously obtained in intact animal experiments, we conclude that the inhibition of citrate oxidation caused by increasing pH and [HCO3-] in slices of renal cortex and kidney mitochondria is an in vitro representation of the inhibition of citrate reabsorption in the nephron that occurs in metabolic alkalosis. Thus, citrate

  11. Citric acid metabolism in hetero- and homofermentative lactic acid bacteria.

    PubMed Central

    Drinan, D F; Robin, S; Cogan, T M

    1976-01-01

    The effect of citrate on production of diacetyl and acetoin by four strains each of heterofermentative and homofermentative lactic acid bacteria capable of utilizing citrate was studied. Acetoin was quantitatively the more important compound. The heterofermentative bacteria produced no acetoin or diacetyl in the absence of citrate, and two strains produced traces of acetoin in its presence. Citrate stimulated the growth rate of the heterofermentative lactobacilli. Acidification of all heterofermentative cultures with citric acid resulted in acetoin production. Destruction of accumulated acetoin appeared to coincide with the disappearance of citrate. All homofermentative bacteria produced more acetoin and diacetyl in the presence of citrate than in its absence. Citrate utilization was begun immediately by the streptococci but was delayed until at least the middle of the exponential phase in the case of the lactobacilli. PMID:5054

  12. Analytical chemistry of the citrate process for flue gas desulfurization

    SciTech Connect

    Marchant, W.N.; May, S.L.; Simpson, W.W.; Winter, J.K.; Beard, H.R.

    1980-01-01

    The citrate process for flue gas desulfurization (FGD) is a product of continuing research by the US Bureau of Mines to meet the goal of minimizing the objectionable effects of minerals industry operations upon the environment. The reduction of SO/sub 2/ in solution by H/sub 2/S to produce elemental sulfur by the citrate process is extremely complex and results in solutions that contain at least nine different sulfur species. Process solution analysis is essential to a clear understanding of process chemistry and its safe, efficient operation. The various chemical species, the approximate ranges of their concentrations in citrate process solutions, and the analytical methods evolved to determine them are hydrogen sulfide (approx. 0M to 0.06M) by specific ion electrode, polysulfides (unknown) by ultraviolet (uv) spectrophotometry, elemental sulfur (approx. 0M to approx. 0.001M dissolved, approx. 0M to approx. 0.1M suspended) by uv spectrophotometry, thiosulfate (approx. 0M to approx. 0.25M) by iodometry or high performance liquid chromatography (HPLC), polythionates (approx. 0M to approx. 0.01M) by thin layer chromatography (TLC), dithionite (searched for but not detected in process solutions) by polarography or TLC, bisulfite (approx. 0M to 0.2M) by iodometry, sulfate (approx. 0M to 1M) by a Bureau-developed gravimetric procedure, citric acid (approx. 0M to 0.5M) by titration or visible colorimetry, glycolic acid (approx. 0M to 1M) by HPLC, sodium (approx. 1.5M) by flame photometry, and chloride by argentometric titration.

  13. Citrate, a specific substrate for the isolation of Clostridium sphenoides.

    PubMed Central

    Walther, R; Hippe, H; Gottschalk, G

    1977-01-01

    With a medium containing citrate as the carbon and energy source, 10 clostridial strains were isolated from various mud samples. Characterization of these strains revealed that they all belonged to the same species, Clostridium sphenoides. Strains of this organism obtained from culture collections were also able to grow citrate, whereas 15 other clostridial species tested were not. Citrate was fermented by C. sphenoides to acetate, ethanol, carbon dioxide, and hydrogen. Experiments with stereospecifically 14C-labeled citrate indicated that citrate lyase was involved in citrate degradation. Images PMID:869540

  14. Beta Blockers Suppress Dextrose-Induced Endoplasmic Reticulum Stress, Oxidative Stress, and Apoptosis in Human Coronary Artery Endothelial Cells.

    PubMed

    Haas, Michael J; Kurban, William; Shah, Harshit; Onstead-Haas, Luisa; Mooradian, Arshag D

    Beta blockers are known to have favorable effects on endothelial function partly because of their capacity to reduce oxidative stress. To determine whether beta blockers can also prevent dextrose-induced endoplasmic reticulum (ER) stress in addition to their antioxidative effects, human coronary artery endothelial cells and hepatocyte-derived HepG2 cells were treated with 27.5 mM dextrose for 24 hours in the presence of carvedilol (a lipophilic beta blockers with alpha blocking activity), propranolol (a lipophilic nonselective beta blockers), and atenolol (a water-soluble selective beta blockers), and ER stress, oxidative, stress and cell death were measured. ER stress was measured using the placental alkaline phosphatase assay and Western blot analysis of glucose regulated protein 78, c-Jun-N-terminal kinase (JNK), phospho-JNK, eukaryotic initiating factor 2α (eIF2α), and phospho-eIF2α and measurement of X-box binding protein 1 (XBP1) mRNA splicing using reverse transcriptase-polymerase chain reaction. Superoxide (SO) generation was measured using the superoxide-reactive probe 2-methyl-6-(4-methoxyphenyl)-3,7-dihydroimidazo[1,2-A]pyrazin-3-one hydrochloride (MCLA) chemiluminescence. Cell viability was measured by propidium iodide staining method. The ER stress, SO production, and cell death induced by 27.5 mM dextrose were inhibited by all 3 beta blockers tested. The antioxidative and ER stress reducing effects of beta blockers were also observed in HepG2 cells. The salutary effects of beta blockers on endothelial cells in reducing both ER stress and oxidative stress may contribute to the cardioprotective effects of these agents.

  15. Aggregation Kinetics of Citrate and Polyvinylpyrrolidone Coated Silver Nanoparticles in Monovalent and Divalent Electrolyte Solutions

    PubMed Central

    Huynh, Khanh An; Chen, Kai Loon

    2011-01-01

    The aggregation kinetics of silver nanoparticles (AgNPs) that were coated with two commonly used capping agents—citrate and polyvinylpyrrolidone (PVP)—were investigated. Time-resolved dynamic light scattering (DLS) was employed to measure the aggregation kinetics of the AgNPs over a range of monovalent and divalent electrolyte concentrations. The aggregation behavior of citrate-coated AgNPs in NaCl was in excellent agreement with the predictions based on Derjaguin–Landau–Verwey–Overbeek (DLVO) theory, and the Hamaker constant of citrate-coated AgNPs in aqueous solutions was derived to be 3.7 × 10-20 J. Divalent electrolytes were more efficient in destabilizing the citrate-coated AgNPs, as indicated by the considerably lower critical coagulation concentrations (2.1 mM CaCl2 and 2.7 mM MgCl2 vs. 47.6 mM NaCl). The PVP-coated AgNPs were significantly more stable than citrate-coated AgNPs in both NaCl and CaCl2, which is likely due to steric repulsion imparted by the large, non-charged polymers. The addition of humic acid resulted in the adsorption of the macromolecules on both citrate- and PVP-coated AgNPs. The adsorption of humic acid induced additional electrosteric repulsion that elevated the stability of both nanoparticles in suspensions containing NaCl or low concentrations of CaCl2. Conversely, enhanced aggregation occurred for both nanoparticles at high CaCl2 concentrations due to interparticle bridging by humic acid clusters. PMID:21630686

  16. Citrate-permeable channels in the plasma membrane of cluster roots from white lupin.

    PubMed

    Zhang, Wen-Hao; Ryan, Peter R; Tyerman, Stephen D

    2004-11-01

    White lupin (Lupinus albus) is well adapted to phosphorus deficiency by developing cluster roots that release large amounts of citrate into the rhizosphere to mobilize the sparingly soluble phosphorus. To determine the mechanism underlying citrate release from cluster roots, we isolated protoplasts from different types of roots of white lupin plants grown in phosphorus-replete (+P) and phosphorus-deficient (-P) conditions and used the patch-clamp technique to measure the whole-cell currents flowing across plasma membrane of these protoplasts. Two main types of anion conductance were observed in protoplasts prepared from cluster root tissue: (1) an inwardly rectifying anion conductance (IRAC) activated by membrane hyperpolarization, and (2) an outwardly rectifying anion conductance (ORAC) that became more activated with membrane depolarization. Although ORAC was an outward rectifier, it did allow substantial inward current (anion efflux) to occur. Both conductances showed citrate permeability, with IRAC being more selective for citrate3- than Cl- (PCit/PCl = 26.3), while ORAC was selective for Cl- over citrate (PCl/PCit = 3.7). Both IRAC and ORAC were sensitive to the anion channel blocker anthracene-9-carboxylic acid. These currents were also detected in protoplasts derived from noncluster roots of -P plants, as well as from normal (noncluster) roots of plants grown with 25 microm phosphorus (+P). No differences were observed in the magnitude or frequency of IRAC and ORAC currents between the cluster roots and noncluster roots of -P plants. However, the IRAC current from +P plants occurred less frequently than in the -P plants. IRAC was unaffected by external phosphate, but ORAC had reduced inward current (anion efflux) when phosphate was present in the external medium. Our data suggest that IRAC is the main pathway for citrate efflux from white lupin roots, but ORAC may also contribute to citrate efflux.

  17. The effect of intrauterine infusion of dextrose on clinical endometritis cure rate and reproductive performance of dairy cows.

    PubMed

    Machado, V S; Oikonomou, G; Ganda, E K; Stephens, L; Milhomem, M; Freitas, G L; Zinicola, M; Pearson, J; Wieland, M; Guard, C; Gilbert, R O; Bicalho, R C

    2015-06-01

    The main objective of this study was to evaluate the intrauterine administration use of 200 mL of 50% dextrose solution as a treatment against clinical endometritis (CE); CE cure rate and reproductive performance were evaluated. Additionally, the association of several relevant risk factors, such as retained placenta (RP), metritis, CE, anovulation, hyperketonemia, and body condition score with reproductive performance, early embryonic mortality, and CE were evaluated. A total of 1,313 Holstein cows housed on 4 commercial dairy farms were enrolled in the study. At 7±3 DIM cows were examined for metritis and had blood collected to determine serum β-hydroxybutyrate concentration. To determine if cows had ovulated at least once before 44±3 DIM, the presence of a corpus luteum was evaluated by ovarian ultrasonography at 30±3 DIM and at 44±3 DIM. At 30±3 DIM, CE was diagnosed using the Metricheck device (SimcroTech, Hamilton, New Zealand); cows with purulent or mucopurulent vaginal discharge were diagnosed as having CE. Cows diagnosed with CE (n=175) were randomly allocated into 2 treatment groups: treatment (intrauterine infusion of 200 mL of 50% dextrose) or control (no infusion). Clinical endometritis cows were re-evaluated as described above at 44±3 DIM, and cows that were free of purulent or mucopurulent vaginal discharge were considered cured. Intrauterine infusion of dextrose tended to have a detrimental effect on CE cure rate, and treatment did not have an effect on first-service conception rate and early embryonic mortality. A multivariable Cox's proportional hazard model was performed to evaluate the effect of several variables on reproductive performance; the variables RP, CE, parity, anovulation, and the interaction term between parity and anovulation were associated with hazard of pregnancy. Cows that did not have RP or CE were more likely to conceive than cows that were diagnosed with RP or CE. Cows that had RP were at 3.36 times higher odds of

  18. Nickel sorption to goethite and montmorillonite in presence of citrate.

    PubMed

    Marcussen, Helle; Holm, Peter E; Strobel, Bjarne W; Hansen, Hans Chr B

    2009-02-15

    Mobility and bioavailability of nickel (Ni) in soil strongly depends on the interaction between Ni(II), ligands, and sorbents like organic matter and minerals. Sorption of Ni(II) and Ni(II)-citrate complexes to goethite and montmorillonite was examined in batch experiments with and without citrate as ligand in the pH range pH 4-7.5. Without citrate, montmorillonite shows higher Ni sorption than goethite. Citrate strongly decreases Ni sorption to montmorillonite; in presence of 100 microM citrate goethite becomes a stronger Ni sorbent than montmorillonite. Ni and citrate sorption was modeled successfully using the diffuse double layer model with the following reactions: Goethite: 3 [triple bond]FeOH + Citrate(3-) + 3H+ <=> [triple bond] Fe3Citrate + 3H2O, [triple bond]FeOH + Ni2+ <=> [triple bond] FeONi + H+ and 2 [triple bond] FeOH + Citrate(3)- + Ni2+ <=> [triple bond] FeONiCitrate(2-) + H+. Montmorillonite: 2X- + Ni2+ <=> X2Ni and [triple bond] AIOH + Ni2+ <=> AIONi+ + H+. Sorption of Ni to a mixture of goethite and montmorillonite could be calculated by use of reactions and constants for the monomineral systems. Without citrate, the sorbed amount of Ni per mass unit in the mixture can be found as a simple average of sorption to the two single sorbents, while in presence of citrate Ni sorption to montmorillonite is strongly influenced by citrate sorption to goethite.

  19. ATP citrate lyase inhibitors as novel cancer therapeutic agents.

    PubMed

    Zu, Xu-Yu; Zhang, Qing-Hai; Liu, Jiang-Hua; Cao, Ren-Xian; Zhong, Jing; Yi, Guang-Hui; Quan, Zhi-Hua; Pizzorno, Giuseppe

    2012-05-01

    ATP citrate lyase (ACL or ACLY) is an extra-mitochondrial enzyme widely distributed in various human and animal tissues. ACL links glucose and lipid metabolism by catalyzing the formation of acetyl-CoA and oxaloacetate from citrate produced by glycolysis in the presence of ATP and CoA. ACL is aberrantly expressed in many immortalized cells and tumors, such as breast, liver, colon, lung and prostate cancers, and is correlated reversely with tumor stage and differentiation, serving as a negative prognostic marker. ACL is an upstream enzyme of the long chain fatty acid synthesis, providing acetyl-CoA as an essential component of the fatty acid synthesis. Therefore, ACL is a key enzyme of cellular lipogenesis and potent target for cancer therapy. As a hypolipidemic strategy of metabolic syndrome and cancer treatment, many small chemicals targeting ACL have been designed and developed. This review article provides an update for the research and development of ACL inhibitors with a focus on their patent status, offering a new insight into their potential application.

  20. Vibrational study of tamoxifen citrate polymorphism

    NASA Astrophysics Data System (ADS)

    Gamberini, M. C.; Baraldi, C.; Tinti, A.; Palazzoli, F.; Ferioli, V.

    2007-09-01

    The trans isomer of ( Z)-2-[ p-(1,2-diphenyl-butenyl)phenoxy]- N, N-dimethyletylamine (tamoxifen) is well known for its endocrine activity as an antiestrogenic agent. Its citrate salt, a widely used pharmaceutical agent, appears in three main polymorphic forms, two of which are well known (I and II) and another form not yet well evidenced. A vibrational study has been conducted for identifying the two known polymorphic forms of tamoxifen citrate (I and II) and for characterising the other form (form III) examined in this study. Other techniques for the characterization of the different polymorphs, such as XRDP, have been used.

  1. Methodology of citrate-based biomaterial development and application

    NASA Astrophysics Data System (ADS)

    Tran, M. Richard

    Biomaterials play central roles in modern strategies of regenerative medicine and tissue engineering. Attempts to find tissue-engineered solutions to cure various injuries or diseases have led to an enormous increase in the number of polymeric biomaterials over the past decade. The breadth of new materials arises from the multiplicity of anatomical locations, cell types, and mode of application, which all place application-specific requirements on the biomaterial. Unfortunately, many of the currently available biodegradable polymers are limited in their versatility to meet the wide range of requirements for tissue engineering. Therefore, a methodology of biomaterial development, which is able to address a broad spectrum of requirements, would be beneficial to the biomaterial field. This work presents a methodology of citrate-based biomaterial design and application to meet the multifaceted needs of tissue engineering. We hypothesize that (1) citric acid, a non-toxic metabolic product of the body (Krebs Cycle), can be exploited as a universal multifunctional monomer and reacted with various diols to produce a new class of soft biodegradable elastomers with the flexibility to tune the material properties of the resulting material to meet a wide range of requirements; (2) the newly developed citrate-based polymers can be used as platform biomaterials for the design of novel tissue engineering scaffolding; and (3) microengineering approaches in the form thin scaffold sheets, microchannels, and a new porogen design can be used to generate complex cell-cell and cell-microenvironment interactions to mimic tissue complexity and architecture. To test these hypotheses, we first developed a methodology of citrate-based biomaterial development through the synthesis and characterization of a family of in situ crosslinkable and urethane-doped elastomers, which are synthesized using simple, cost-effective strategies and offer a variety methods to tailor the material properties to

  2. Effect of ranitidine bismuth citrate on postprandial plasma gastrin and pepsinogens.

    PubMed Central

    Fraser, A G; Lam, W M; Luk, Y W; Sercombe, J; Sawyerr, A M; Hudson, M; Samloff, I M; Pounder, R E

    1993-01-01

    Ranitidine bismuth citrate was compared with an equipotent dose of ranitidine, to determine whether the former, by an anti-Helicobacter pylori activity, would counteract the rise of gastrin resulting from ranitidine's gastric acid antisecretory activity. Twenty four men with duodenal ulcers were studied before and on the 8th day of dosing with either ranitidine bismuth citrate 800 mg twice daily or ranitidine 300 mg twice daily (double blind, randomised, parallel groups). Fasting and postprandial plasma gastrin and plasma pepsinogen I and II concentrations were measured, and a 13C-urea breath test was performed before and on the 8th day of dosing. The 13C-urea breath tests were positive in 21 patients before dosing and remained positive in nine of nine of the ranitidine dosed patients, whereas only two of 12 patients treated with ranitidine bismuth citrate remained positive. The expected rise in meal stimulated plasma gastrin with ranitidine was seen in the 12 patients who received ranitidine but, despite suppression of H pylori urease activity in 10 of 12 patients taking ranitidine bismuth citrate, there was no attenuation of the meal stimulated gastrin rise. There was no significant difference in the mean derived (4 hour) plasma pepsinogen I and II concentrations after dosing with ranitidine or ranitidine bismuth citrate. PMID:8472980

  3. Enhancing radium solubilization in soils by citrate, EDTA, and EDDS chelating amendments.

    PubMed

    Prieto, C; Lozano, J C; Blanco Rodríguez, P; Tomé, F Vera

    2013-04-15

    The effect of three chelating agents (citrate, EDTA, and EDDS) on the solubilization of radium from a granitic soil was studied systematically, considering different soil pH values, chelating agent concentrations, and leaching times. For all the chelating agents tested, the amount of radium leached proved to be strongly dependent on the pH of the substrate: only for acidic conditions did the amount of radium released increase significantly relative to the controls. Under the best conditions, the radium released from the amended soil was greater by factors of 20 in the case of citrate, 18 for EDTA, and 14 for EDDS. The greatest improvement in the release of radium was obtained for the citrate amendment at the highest concentration tested (50 mmol kg(-1)). A slightly lower amount of radium was leached with EDTA at 5 mmol kg(-1) soil, but the solubilization over time was very different from that observed with citrate or EDDS. With EDTA, a maximum in radium leaching was reached on the first day after amendment, while with citrate, the maximum was attained on the fourth day. With EDDS, radium leaching increased slightly but steadily with time (until the sixth day), but the net effect for the period tested was the lowest of the three reagents.

  4. [Fenibut and its citrate prevent psychoneurological disorders caused by chronic stress (paradoxical sleep deprivation)].

    PubMed

    Tiurenkov, I N; Bagmetova, V V; Borodkina, L E; Berestovitskaia, V M; Vasil'eva, O S

    2012-01-01

    The antistress protective action of two structural analogs of GABA, fenibut and its salt with citric acid (fenibut citrate, citrocard, RGPU-147), has been studied using a model of chronic stress caused by seven-fold 24-h deprivation of paradoxical sleep phase at an interval of 24 h between the deprivations. It is established that fenibut and fenibut citrate produce a protective action by (i) reducing the intensity of emotional disorders in the open-field test and elevated plus maze test, (ii) decreasing cognitive disorders in the tests for conditioned avoidance response and extrapolatory deliverance; and (iii) limiting stress reaction due to a decrease in the intensity of adrenal hypertrophy, thymus involution, and stomach mucous membrane ulceration. Fenibut citrate surpasses fenibut in the intensity of antistress protective action.

  5. Interaction of monolaurin, eugenol and sodium citrate on growth of common meat spoilage and pathogenic organisms.

    PubMed

    Blaszyk, M; Holley, R A

    1998-02-17

    Interactions of monolaurin, eugenol (phenolic compound) and sodium citrate (chelator) on the growth of six organisms including common meat spoilage (Lactobacillus curvatus, Lactobacillus sake, Leuconostoc mesenteroides, Brochothrix thermosphacta) and pathogenic (Escherichia coli O157:H7 and Listeria monocytogenes) organisms were investigated. The combinations of 100 to 250 ppm monolaurin with 500 and 1000 ppm eugenol, and 0.2 and 0.4% sodium citrate were more effective than each component separately. More than one combination prevented detectable growth of each organism. Lactic acid bacteria (LAB) and E. coli O157:H7 were most resistant and L. monocytogenes and B. thermosphacta most sensitive to control by the chosen combinations. The presence of sodium citrate was necessary to yield potent inhibition of Lb. curvatus and Lb. sake growth by the monolaurin and eugenol combinations.

  6. Phloretin and citrate promote the differentiation rate from epimastigote to metacyclic forms of Trypanosoma cruzi.

    PubMed

    Adroher, F J; Osuna, A; Lupiáñez, J A

    1991-11-01

    We have investigated the effects of the metabolic inhibitors, phloretin, 2-deoxy-D-glucose, maleate and trans-aconitate, as well as two intermediates of the tricarboxylic-acid cycle, acetate and citrate, on the growth and metacyclogenesis of Trypanosoma cruzi. 0.1 mM phloretin increased the percentage of metacyclic forms about 2.7-fold without affecting growth rate, whereas the other inhibitors had no apparent effect on either growth or differentiation rates. The addition of 5 mM citrate stimulated differentiation by about 2.6-fold. When either 10 mM citrate or 10 mM acetate were added, on the other hand, both the growth and differentiation rates were severely inhibited.

  7. Activity of urokinase diluted in 0.9% sodium chloride injection or 5% dextrose injection and stored in glass or plastic syringes.

    PubMed

    Patel, J P; Tran, L T; Sinai, W J; Carr, L J

    1991-07-01

    The effects of the diluent, the container, the i.v. set, and the drug concentration on the adsorption of urokinase to i.v. administration systems were studied, along with the compatibility of urokinase with plastic and glass syringes. Solutions of urokinase 1500 and 5000 IU/mL in 0.9% sodium chloride injection and 5% dextrose injection in glass and polyvinyl chloride (PVC) containers were sampled at 2 and 30 minutes. Administration sets were attached to PVC containers containing the urokinase-5% dextrose injection solutions, and samples were collected at 90 and 150 minutes. Glass and polypropylene syringes containing urokinase 5000 IU/mL in 0.9% sodium chloride injection or 5% dextrose injection were sampled at 0, 4, 8, and 24 hours. Urokinase activity was measured by an in vitro clot lysis assay. No urokinase diluted in 0.9% sodium chloride injection adsorbed to glass or PVC containers. For urokinase 1500 IU/mL in 5% dextrose injection, a loss of 15% to 20% occurred almost instantaneously in PVC containers; additional losses to the infusion sets were minimal. However, for urokinase 5000 IU/mL in 5% dextrose injection, no losses were observed in the PVC systems. No drug loss to glass bottles was seen for urokinase 1500 or 5000 IU/mL in 5% dextrose injection. Urokinase potency remained constant in polypropylene and glass syringes for 24 hours. To minimize urokinase sorption to PVC containers, higher concentrations of urokinase diluted in 5% dextrose injection should be used, provided that clinical safety and efficacy are not compromised. The use of 0.9% sodium chloride injection as a diluent also prevents sorption losses.

  8. Evidence that Osteoblasts are Specialized Citrate-producing Cells that Provide the Citrate for Incorporation into the Structure of Bone

    PubMed Central

    Franklin, Renty B.; Chellaiah, Meena; Zou, Jing; Reynolds, Mark A.; Costello, Leslie C.

    2015-01-01

    Citrate is a major component of bone in all vertebrates, but its implications in bone have remained largely unknown. Recent studies identified that citrate is incorporated into the structure of the hydroxyapatite nanocrystal/collagen complex; and is essential for the important biomechanical properties of bone. This raises the important question, “What is the source of citrate for incorporation into bone?”; A question that heretofore had remained unresolved. Studies in this report were designed to determine the plausibility of our concept that the osteoblasts are specialized citrate-producing cells, which provide the citrate that is incorporated into the structure of bone; and that osteogenic differentiation of mesenchyme cells leads to the development of the citrate-producing osteoblasts. The results demonstrated that primary human osteoblasts exhibit the capability of citrate-production. Undifferentiated mesenchyme cells do not exhibit the capability of citrate production; and osteogenic differentiation results in citrate-producing osteoblasts. The up-regulation of zinc uptake transporter ZIP1 is essential for the manifestation of the citrate-producing capability of the osteoblasts. We determined that osteoblast transport of citrate from plasma is not a likely source of citrate in bone. Thus, this study establishes for the first time that the osteoblasts are specialized citrate-producing cells that provide the citrate for incorporation into the structure of bone; and that mesenchyme cell osteogenesis leads to differentiated citrate-producing osteoblasts. This is a new understanding; which must include the osteogenic development of citrate-producing osteoblasts, and the process of “citration” in concert with mineralization during bone formation. It also provides a new understanding of the role of bone in the homeostatic maintenance of plasma citrate concentration. PMID:25745519

  9. Efficacy and Safety of a Citrate-Based Protocol for Sustained Low-Efficiency Dialysis in AKI Using Standard Dialysis Equipment

    PubMed Central

    Regolisti, Giuseppe; Cademartiri, Carola; Cabassi, Aderville; Picetti, Edoardo; Barbagallo, Maria; Gherli, Tiziano; Castellano, Giuseppe; Morabito, Santo; Maggiore, Umberto

    2013-01-01

    Summary Background and objectives A simple anticoagulation protocol was developed for sustained low-efficiency dialysis (SLED) in patients with AKI, based on the use of anticoagulant citrate dextrose solution formulation A (ACD-A) and standard dialysis equipment. Patients’ blood recalcification was obtained from calcium backtransport from dialysis fluid. Design, setting, participants, & measurements All patients treated with SLED (8- to 12-hour sessions) for AKI in four intensive care units of a university hospital were studied over a 30-month period, from May 1, 2008 to September 30, 2010. SLED interruptions and their causes, hemorrhagic complications, as well as coagulation parameters, ionized calcium, and blood citrate levels were recorded. Results This study examined 807 SLED sessions in 116 patients (mean age of 69.7 years [SD 12.1]; mean Acute Physiology and Chronic Health Evaluation II score of 23.8 [4.6]). Major bleeding was observed in six patients (5.2% or 0.4 episodes/100 person-days follow-up while patients were on SLED treatment). Citrate accumulation never occurred, even in patients with liver dysfunction. Intravenous calcium for ionized hypocalcemia (< 3.6 mg/dl or < 0.9 mmol/L) was needed in 28 sessions (3.4%); in 8 of these 28 sessions (28.6%), low ionized calcium was already present before SLED start. In 92.6% of treatments, SLED was completed within the scheduled time (median 8 hours). Interruptions of SLED by impending/irreversible clotting were recorded in 19 sessions (2.4%). Blood return was complete in 98% of the cases. In-hospital mortality was 45 of 116 patients (38.8%). Conclusions This study protocol affords efficacious and safe anticoagulation of the SLED circuit, avoiding citrate accumulation and, in most patients, systematic calcium supplementation; it can be implemented with commercial citrate solutions, standard dialysis equipment, on-line produced dialysis fluid, and minimal laboratory monitoring. PMID:23990164

  10. 21 CFR 73.2110 - Bismuth citrate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... restrictions. The color additive bismuth citrate may be safely used in cosmetics intended for coloring hair on..., eyebrows, or hair on parts of the body other than the scalp. (d) Labeling. (1) The label of the color... abraded scalp. Do not use to color eyelashes, eyebrows, or hair on parts of the body other than the...

  11. 21 CFR 73.2110 - Bismuth citrate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... restrictions. The color additive bismuth citrate may be safely used in cosmetics intended for coloring hair on..., eyebrows, or hair on parts of the body other than the scalp. (d) Labeling. (1) The label of the color... abraded scalp. Do not use to color eyelashes, eyebrows, or hair on parts of the body other than the...

  12. 21 CFR 73.2110 - Bismuth citrate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... restrictions. The color additive bismuth citrate may be safely used in cosmetics intended for coloring hair on..., eyebrows, or hair on parts of the body other than the scalp. (d) Labeling. (1) The label of the color... abraded scalp. Do not use to color eyelashes, eyebrows, or hair on parts of the body other than the...

  13. 21 CFR 73.2110 - Bismuth citrate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... restrictions. The color additive bismuth citrate may be safely used in cosmetics intended for coloring hair on..., eyebrows, or hair on parts of the body other than the scalp. (d) Labeling. (1) The label of the color... abraded scalp. Do not use to color eyelashes, eyebrows, or hair on parts of the body other than the...

  14. 21 CFR 73.2110 - Bismuth citrate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... restrictions. The color additive bismuth citrate may be safely used in cosmetics intended for coloring hair on..., eyebrows, or hair on parts of the body other than the scalp. (d) Labeling. (1) The label of the color... abraded scalp. Do not use to color eyelashes, eyebrows, or hair on parts of the body other than the...

  15. 21 CFR 582.5449 - Manganese citrate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Manganese citrate. 582.5449 Section 582.5449 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients and/or...

  16. 21 CFR 582.5195 - Calcium citrate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Calcium citrate. 582.5195 Section 582.5195 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients and/or...

  17. 21 CFR 582.5449 - Manganese citrate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Manganese citrate. 582.5449 Section 582.5449 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients and/or...

  18. 21 CFR 582.5195 - Calcium citrate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Calcium citrate. 582.5195 Section 582.5195 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients and/or...

  19. 21 CFR 582.5449 - Manganese citrate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Manganese citrate. 582.5449 Section 582.5449 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients and/or...

  20. 21 CFR 582.5449 - Manganese citrate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Manganese citrate. 582.5449 Section 582.5449 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients and/or...

  1. 21 CFR 582.5195 - Calcium citrate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Calcium citrate. 582.5195 Section 582.5195 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients and/or...

  2. 21 CFR 582.5195 - Calcium citrate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Calcium citrate. 582.5195 Section 582.5195 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients and/or...

  3. 21 CFR 582.5449 - Manganese citrate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Manganese citrate. 582.5449 Section 582.5449 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients and/or...

  4. 21 CFR 582.5195 - Calcium citrate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Calcium citrate. 582.5195 Section 582.5195 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients and/or...

  5. 14 N NQR spectrum of sildenafil citrate

    NASA Astrophysics Data System (ADS)

    Stephenson, David; Singh, Nadia

    2015-04-01

    The 14N nuclear quadrupole resonance (NQR) spectrum of sildenafil citrate tablets has been recorded allowing the quadrupole coupling constants and asymmetry parameters of all six unique nitrogen atoms in its structure to be determined. A density function calculation gives results that are largely in agreement with the experimental values.

  6. Cloning and characterization of the Salmonella typhimurium-specific chemoreceptor Tcp for taxis to citrate and from phenol.

    PubMed

    Yamamoto, K; Imae, Y

    1993-01-01

    Salmonella typhimurium shows an attractant response to citrate and a repellent response to phenol, and a chemoreceptor mediating these responses has been identified and named Tcp (taxis to citrate and away from phenol). Tcp is one of the methyl-accepting chemotaxis proteins that have a molecular mass of approximately 60 kDa estimated by SDS/PAGE, and its methylation level is increased by citrate and decreased by phenol. Tcp also mediates an attractant response to metal-citrate complexes. The complete nucleotide sequence of the tcp coding region has been determined. The deduced amino acid sequence of Tcp, consisting of 547-amino acid residues, is homologous with that of the aspartate chemoreceptor of S. typhimurium. Thus, Tcp is another member of the bacterial transmembrane chemoreceptor family. Because citrate is a good carbon source for S. typhimurium but is not a carbon source for the closely related species Escherichia coli and because citrate utilization is used as a key diagnostic character to distinguish these species, it is reasonable to assume that Tcp is specific to S. typhimurium.

  7. 40 CFR 721.10357 - Iron, citrate phosphate potassium complexes.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Iron, citrate phosphate potassium... Specific Chemical Substances § 721.10357 Iron, citrate phosphate potassium complexes. (a) Chemical..., citrate phosphate potassium complexes (PMN P-09-382; CAS No. 120579-31-9) is subject to reporting...

  8. 40 CFR 721.10357 - Iron, citrate phosphate potassium complexes.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Iron, citrate phosphate potassium... Specific Chemical Substances § 721.10357 Iron, citrate phosphate potassium complexes. (a) Chemical..., citrate phosphate potassium complexes (PMN P-09-382; CAS No. 120579-31-9) is subject to reporting...

  9. 40 CFR 721.10357 - Iron, citrate phosphate potassium complexes.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Iron, citrate phosphate potassium... Specific Chemical Substances § 721.10357 Iron, citrate phosphate potassium complexes. (a) Chemical..., citrate phosphate potassium complexes (PMN P-09-382; CAS No. 120579-31-9) is subject to reporting...

  10. 21 CFR 573.580 - Iron-choline citrate complex.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.580 Iron-choline citrate complex. Iron-choline citrate complex made by... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Iron-choline citrate complex. 573.580 Section...

  11. 21 CFR 573.580 - Iron-choline citrate complex.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.580 Iron-choline citrate complex. Iron-choline citrate complex made by... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Iron-choline citrate complex. 573.580 Section...

  12. 21 CFR 573.580 - Iron-choline citrate complex.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.580 Iron-choline citrate complex. Iron-choline citrate complex made by... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Iron-choline citrate complex. 573.580 Section...

  13. 21 CFR 573.580 - Iron-choline citrate complex.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.580 Iron-choline citrate complex. Iron-choline citrate complex made by... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Iron-choline citrate complex. 573.580 Section...

  14. 21 CFR 172.370 - Iron-choline citrate complex.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Iron-choline citrate complex. 172.370 Section 172... Nutritional Additives § 172.370 Iron-choline citrate complex. Iron-choline citrate complex made by reacting... source of iron in foods for special dietary use....

  15. 21 CFR 172.430 - Iron ammonium citrate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Iron ammonium citrate. 172.430 Section 172.430... ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Anticaking Agents § 172.430 Iron ammonium citrate. Iron ammonium citrate may be safely used in food in accordance with the...

  16. 21 CFR 573.580 - Iron-choline citrate complex.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Iron-choline citrate complex. 573.580 Section 573... Food Additive Listing § 573.580 Iron-choline citrate complex. Iron-choline citrate complex made by... used as a source of iron in animal feed....

  17. 21 CFR 520.622b - Diethylcarbamazine citrate syrup.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Diethylcarbamazine citrate syrup. 520.622b Section... Diethylcarbamazine citrate syrup. (a)(1) Specifications. Each milliliter of syrup contains 60 milligrams of diethylcarbamazine citrate. (2) Sponsor. See No. 053501 in § 510.600(c) of this chapter. (3) Conditions of use....

  18. 21 CFR 520.622b - Diethylcarbamazine citrate syrup.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Diethylcarbamazine citrate syrup. 520.622b Section... Diethylcarbamazine citrate syrup. (a)(1) Specifications. Each milliliter of syrup contains 60 milligrams of diethylcarbamazine citrate. (2) Sponsor. See No. 053501 in § 510.600(c) of this chapter. (3) Conditions of use....

  19. 21 CFR 520.622b - Diethylcarbamazine citrate syrup.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Diethylcarbamazine citrate syrup. 520.622b Section... Diethylcarbamazine citrate syrup. (a)(1) Specifications. Each milliliter of syrup contains 60 milligrams of diethylcarbamazine citrate. (2) Sponsor. See No. 053501 in § 510.600(c) of this chapter. (3) Conditions of use....

  20. 21 CFR 520.623 - Diethylcarbamazine citrate, oxibendazole chewable tablets.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Diethylcarbamazine citrate, oxibendazole chewable... § 520.623 Diethylcarbamazine citrate, oxibendazole chewable tablets. (a) Specifications. Each tablet contains either 60, 120, or 180 milligrams of diethylcarbamazine citrate with 45, 91, or 136 milligrams...

  1. 21 CFR 520.623 - Diethylcarbamazine citrate, oxibendazole chewable tablets.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Diethylcarbamazine citrate, oxibendazole chewable... § 520.623 Diethylcarbamazine citrate, oxibendazole chewable tablets. (a) Specifications. Each tablet contains either 60, 120, or 180 milligrams of diethylcarbamazine citrate with 45, 91, or 136 milligrams...

  2. 21 CFR 520.623 - Diethylcarbamazine citrate, oxibendazole chewable tablets.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Diethylcarbamazine citrate, oxibendazole chewable... § 520.623 Diethylcarbamazine citrate, oxibendazole chewable tablets. (a) Specifications. Each tablet contains either 60, 120, or 180 milligrams of diethylcarbamazine citrate with 45, 91, or 136 milligrams...

  3. 21 CFR 520.622d - Diethylcarbamazine citrate capsules.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Diethylcarbamazine citrate capsules. 520.622d... Diethylcarbamazine citrate capsules. (a) Specifications. Each capsule contains 12.5, 50, 200, or 400 milligrams (mg) diethylcarbamazine citrate. (b) Sponsor. See No. 011014 in § 510.600(c) of this chapter. (c) Conditions of use...

  4. Photodegradation of parabens by Fe(III)-citrate complexes at circumneutral pH: matrix effect and reaction mechanism.

    PubMed

    Feng, Xiaonan; Chen, Yong; Fang, Yuan; Wang, Xiaoyue; Wang, Zongping; Tao, Tao; Zuo, Yuegang

    2014-02-15

    The photodegradation of four parabens including methyl-, ethyl-, propyl-, and butyl-paraben in the presence of Fe(III)-citrate complexes under simulated sunlight was investigated. The degradation of parabens increased with decreasing pH within the range of 5.0-8.0 at the Fe(III)-to-citrate ratio of 10:150 (μM). The addition of low-molecular-weight carboxylic acids showed different effects on the photodegradation of methylparaben. The low-photoreactive carboxylic acids inhibited the photodegradation of methylparaben in the order of formic acid>succinic acid>acetic acid>malonic acid. In contrast, oxalic acid enhanced the photodegradation and exhibited appreciable synergistic effect with Fe(III)-citrate at concentration higher than 500 μM. Up to 99.0% of substrate was degraded after 30 min at pH6.0 in the Fe(III)-citrate-oxalate system. The various fractions of fulvic acid inhibited the photodegradation of methylparaben. The inhibition increased with increasing nominal molecular weight of fractionated fulvic acid. Moreover, the photodegradation of methylparaben was inhibited in natural waters in the order of Liangzi Lake

  5. Early initiation of low-level parenteral dextrose induces an accelerated diabetic phenotype in septic C57BL/6J mice

    PubMed Central

    Singamsetty, Srikanth; Shah, Faraaz Ali; Guo, Lanping; Watanabe, Yoshio; McDonald, Sherie; Sharma, Rohit; Zhang, Yingze; Alonso, Laura C.; O’Donnell, Christopher P.; McVerry, Bryan J.

    2016-01-01

    Development of hyperglycemia during sepsis is associated with increased morbidity and mortality. Nutritional support is common practice in the intensive care unit, but the metabolic effects are not well understood. The purpose of this study is to determine the effect of early low-level calorie provision on the development of hyperglycemia in a clinically relevant murine model of sepsis. C57BL/6J mice underwent femoral arterial and venous catheterization followed by cecal ligation and puncture (CLP) or sham surgery and low-dose intravenous dextrose or saline infusion. Blood glucose, plasma insulin, and cytokines were measured after 24 h. Additional septic mice underwent hyperinsulinemic-euglycemic clamps or received intravenous insulin concurrent with dextrose to determine whole-body insulin sensitivity and test the efficacy of insulin to reverse hyperglycemia. Neither dextrose infusion nor CLP alone induced hyperglycemia. Early initiation of low-level dextrose in septic mice produced a variable glycemic response: 49% maintained euglycemia (blood glucose <200) and 27% developed severe hyperglycemia (blood glucose≥600). Hyperglycemia was associated with increased inflammation and reduced insulin secretion and sensitivity compared with control mice or CLP mice maintaining euglycemia. Insulin prevented the progression to severe hyperglycemia but was ineffective in reestablishing glycemic control once hyperglycemia had developed. In conclusion, early initiation of clinically relevant low-level dextrose (~20% daily caloric requirements) precipitated hyperglycemia akin to an acute diabetic phenotype in septic mice characterized by decreased insulin sensitivity, decreased insulin secretion, and an increased inflammatory response. PMID:26624964

  6. The mechanisms of citrate on regulating the distribution of carbon flux in the biosynthesis of uridine 5'-monophosphate by Saccharomyces cerevisiae.

    PubMed

    Chen, Yong; Li, Shuya; Xiong, Jian; Li, Zhenjiang; Bai, Jianxin; Zhang, Lei; Ye, Qi; Ouyang, Pingkai; Ying, Hanjie

    2010-03-01

    A whole cell biocatalytic process for uridine 5'-monophosphate (UMP) production from orotic acid by Saccharomyces cerevisiae was developed. The concentration of UMP was increased by 23% when 1 g l(-1) sodium citrate was fed into the broth. Effects of citrate addition on UMP production were investigated. Glucose-6-phosphate pool was elevated by onefold, while FBP and pyruvate were decreased by 42% and 40%, respectively. Organic acid pools such as acetate and succinate were averagely decreased by 30% and 49%. The results demonstrated that manipulation of citrate levels could be used as a novel tool to regulate the metabolic fluxes distribution among glycolysis, pentose phosphate pathway, and TCA cycle.

  7. Uptake of α-Ketoglutarate by Citrate Transporter CitP Drives Transamination in Lactococcus lactis

    PubMed Central

    Pudlik, Agata M.

    2013-01-01

    Transamination is the first step in the conversion of amino acids into aroma compounds by lactic acid bacteria (LAB) used in food fermentations. The process is limited by the availability of α-ketoglutarate, which is the best α-keto donor for transaminases in LAB. Here, uptake of α-ketoglutarate by the citrate transporter CitP is reported. Cells of Lactococcus lactis IL1403 expressing CitP showed significant levels of transamination activity in the presence of α-ketoglutarate and one of the amino acids Ile, Leu, Val, Phe, or Met, while the same cells lacking CitP showed transamination activity only after permeabilization of the cell membrane. Moreover, the transamination activity of the cells followed the levels of CitP in a controlled expression system. The involvement of CitP in the uptake of the α-keto donor was further demonstrated by the increased consumption rate in the presence of l-lactate, which drives CitP in the fast exchange mode of transport. Transamination is the only active pathway for the conversion of α-ketoglutarate in IL1403; a stoichiometric conversion to glutamate and the corresponding α-keto acid from the amino acids was observed. The transamination activity by both the cells and the cytoplasmic fraction showed a remarkably flat pH profile over the range from pH 5 to pH 8, especially with the branched-chain amino acids. Further metabolism of the produced α-keto acids into α-hydroxy acids and other flavor compounds required the coupling of transamination to glycolysis. The results suggest a much broader role of the citrate transporter CitP in LAB than citrate uptake in the citrate fermentation pathway alone. PMID:23204417

  8. Involvement of CitCHX and CitDIC in Developmental-Related and Postharvest-Hot-Air Driven Citrate Degradation in Citrus Fruits

    PubMed Central

    Lin, Qiong; Li, Shaojia; Dong, Wencheng; Feng, Chao; Yin, Xueren; Xu, Changjie; Sun, Chongde; Chen, Kunsong

    2015-01-01

    Citrate is the predominant organic acid associated with taste in citrus fruit. Although citrate metabolism has been widely studied in recent years, the potential contributions of transport proteins to citrate content remain unclear. In the present study, high-acid citrus fruit Gaocheng (‘GC’, Citrus sp.) and low-acid citrus fruit Satsuma mandarin (‘SM’, Citrus unshiu Marc.) were selected for study, and the degradation of citrate was deduced to be the main cause of the difference in acidity in fully mature fruits. RNA-seq analysis was carried out on ‘GC’ and ‘SM’ fruit samples over the same time course, and the results indicated that citrate degradation occurred mainly through the glutamine pathway, catalyzed by CitAco3-CitGS2-CitGDU1, and also two transport-related genes, CitCHX and CitDIC, were shown to be associated with citrate degradation. These results were confirmed by real-time PCR. In postharvest ‘GC’ fruit, the expressions of these two transport-related genes were induced by 2-fold under hot air treatment, accompanied by a reduction of 7%-9% in total acid degradation. Transient expression of CitCHX and CitDIC in tobacco leaves was performed, and the citrate content was reduced by 62%, 75% and 78% following CitCHX, CitDIC and CitCHX plus CitDIC treatments, respectively, as compared with expression of an empty vector. Overall, these data indicated that two transport proteins, CitCHX and CitDIC, are not only involved in citrate degradation during fruit development, but also involved in postharvest hot air triggered citrate reduction. PMID:25738939

  9. Involvement of CitCHX and CitDIC in developmental-related and postharvest-hot-air driven citrate degradation in citrus fruits.

    PubMed

    Lin, Qiong; Li, Shaojia; Dong, Wencheng; Feng, Chao; Yin, Xueren; Xu, Changjie; Sun, Chongde; Chen, Kunsong

    2015-01-01

    Citrate is the predominant organic acid associated with taste in citrus fruit. Although citrate metabolism has been widely studied in recent years, the potential contributions of transport proteins to citrate content remain unclear. In the present study, high-acid citrus fruit Gaocheng ('GC', Citrus sp.) and low-acid citrus fruit Satsuma mandarin ('SM', Citrus unshiu Marc.) were selected for study, and the degradation of citrate was deduced to be the main cause of the difference in acidity in fully mature fruits. RNA-seq analysis was carried out on 'GC' and 'SM' fruit samples over the same time course, and the results indicated that citrate degradation occurred mainly through the glutamine pathway, catalyzed by CitAco3-CitGS2-CitGDU1, and also two transport-related genes, CitCHX and CitDIC, were shown to be associated with citrate degradation. These results were confirmed by real-time PCR. In postharvest 'GC' fruit, the expressions of these two transport-related genes were induced by 2-fold under hot air treatment, accompanied by a reduction of 7%-9% in total acid degradation. Transient expression of CitCHX and CitDIC in tobacco leaves was performed, and the citrate content was reduced by 62%, 75% and 78% following CitCHX, CitDIC and CitCHX plus CitDIC treatments, respectively, as compared with expression of an empty vector. Overall, these data indicated that two transport proteins, CitCHX and CitDIC, are not only involved in citrate degradation during fruit development, but also involved in postharvest hot air triggered citrate reduction.

  10. Why sildenafil and sildenafil citrate monohydrate crystals are not stable?

    PubMed

    Sawatdee, Somchai; Pakawatchai, Chaveng; Nitichai, Kwanjai; Srichana, Teerapol; Phetmung, Hirihattaya

    2015-10-01

    Sildenafil citrate was crystallized by various techniques aiming to determine the behavior and factors affecting the crystal growth. There are only 2 types of sildenafil obtaining from crystallization: sildenafil (1) and sildenafil citrate monohydrate (2). The used techniques were (i) crystallization from saturated solutions, (ii) addition of an antisolvent, (iii) reflux and (iv) slow solvent evaporation method. By pursuing these various methods, our work pointed that the best formation of crystal (1) was obtained from technique no. (i). Surprisingly, the obtained crystals (1) were perfected if the process was an acidic pH at a cold temperature then perfect crystals occurred within a day. Crystals of compound (2) grew easily using technique no. (ii) which are various polar solvents over a wide range of pH and temperature preparation processes. The infrared spectroscopy and nuclear magnetic resonance spectra fit well with these two X-ray crystal structures. The crystal structures of sildenafil free base and salt forms were different from their different growing conditions leading to stability difference.

  11. Why sildenafil and sildenafil citrate monohydrate crystals are not stable?

    PubMed Central

    Sawatdee, Somchai; Pakawatchai, Chaveng; Nitichai, Kwanjai; Srichana, Teerapol; Phetmung, Hirihattaya

    2015-01-01

    Sildenafil citrate was crystallized by various techniques aiming to determine the behavior and factors affecting the crystal growth. There are only 2 types of sildenafil obtaining from crystallization: sildenafil (1) and sildenafil citrate monohydrate (2). The used techniques were (i) crystallization from saturated solutions, (ii) addition of an antisolvent, (iii) reflux and (iv) slow solvent evaporation method. By pursuing these various methods, our work pointed that the best formation of crystal (1) was obtained from technique no. (i). Surprisingly, the obtained crystals (1) were perfected if the process was an acidic pH at a cold temperature then perfect crystals occurred within a day. Crystals of compound (2) grew easily using technique no. (ii) which are various polar solvents over a wide range of pH and temperature preparation processes. The infrared spectroscopy and nuclear magnetic resonance spectra fit well with these two X-ray crystal structures. The crystal structures of sildenafil free base and salt forms were different from their different growing conditions leading to stability difference. PMID:26594116

  12. The metabolic fate of the products of citrate cleavage. Adenosine triphosphate citrate lyase and nicotinamide–adenine dinucleotide phosphate-linked malate dehydrogenase in foetal and adult liver from ruminants and non-ruminants

    PubMed Central

    Hanson, R. W.; Ballard, F. J.

    1968-01-01

    1. Foetal rat liver slices incorporate the C-3 of aspartate and C-2 of glutamate into fatty acids at rates equal to those observed with adult rat liver slices. Incorporation of either of these labelled carbon atoms into fatty acids would require a functioning citrate-cleavage pathway which consists of the enzymes ATP–citrate lyase, NAD–malate dehydrogenase and NADP–malate dehydrogenase. However, NADP–malate dehydrogenase is present in foetal rat liver at only 5% of the activity detectable in adult rat liver. 2. From these findings and the effect of cofactors on the formation of 14CO2 from [1,5-14C2]citrate in liver supernatant fractions (100000g), it is suggested that NADP–malate dehydrogenase limits the citrate-cleavage sequence. 3. Measurement of the citrate-cleavage pathway by incorporation studies with [3-14C]aspartate and [U-14C]glucose and by determining the activities of ATP–citrate lyase and NADP–malate dehydrogenase have shown that this sequence of reactions is present in the liver of the bovine foetus but not in the adult. However, C-2 of glutamate is not incorporated into fatty acids or non-saponifiable lipid by bovine liver slices. This finding as well as those presented above for the adult and foetal rat liver are interpreted on the basis of a competition between phosphoenolpyruvate carboxykinase and NAD–malate dehydrogenase for oxaloacetate produced by the cleavage of citrate in the cytosol. PMID:4386407

  13. Substrate Specificity of the Citrate Transporter CitP of Lactococcus lactis

    PubMed Central

    Pudlik, Agata M.

    2012-01-01

    The citrate transporter CitP of lactic acid bacteria catalyzes electrogenic precursor-product exchange of citrate versus l-lactate during citrate-glucose cometabolism. In the absence of sugar, l-lactate is replaced by the metabolic intermediates/end products pyruvate, α-acetolactate, and acetate. In this study, the binding and translocation properties of CitP were analyzed systematically for a wide variety of mono- and dicarboxylates of the form X-CR2-COO−, where X represents OH (2-hydroxy acid), O (2-keto acid), or H (acid) and R groups differ in size, hydrophobicity, and composition. It follows that CitP is a very promiscuous carboxylate transporter. A carboxylate group is both essential and sufficient for recognition by the transporter. A C-2 atom is not essential, formate is a substrate, and C-2 may be part of a ring structure, as in benzoate. The R group may be as bulky as an indole ring structure. For all monocarboxylates of the form X-CHR-COO−, the hydroxy (X = OH) analogs were the preferred substrates. The preference for keto (X = O) or acid (X = H) analogs was dependent on the bulkiness of the R group, such that the acid was preferred for small R groups and the 2-ketoacid was preferred for more bulky R groups. The C4 to C6 dicarboxylates succinate, glutarate, and adipate were also substrates of CitP. The broad substrate specificity is discussed in the context of a model of the binding site of CitP. Many of the substrates of CitP are intermediates or products of amino acid metabolism, suggesting that CitP may have a broader physiological function than its role in citrate fermentation alone. PMID:22563050

  14. Use of Potassium Citrate to Reduce the Risk of Renal Stone Formation During Spaceflight

    NASA Technical Reports Server (NTRS)

    Whitson, P. A.; Pietrzyk, R. A.; Sams, C. F.; Jones, J. A.; Nelman-Gonzalez, M.; Hudson, E. K.

    2008-01-01

    Introduction: NASA s Vision for Space Exploration centers on exploration class missions including the goals of returning to the moon and landing on Mars. One of NASA s objectives is to focus research on astronaut health and the development of countermeasures that will protect crewmembers during long duration voyages. Exposure to microgravity affects human physiology and results in changes in the urinary chemical composition favoring urinary supersaturation and an increased risk of stone formation. Nephrolithiasis is a multifactorial disease and development of a renal stone is significantly influenced by both dietary and environmental factors. Previous results from long duration Mir and short duration Shuttle missions have shown decreased urine volume, pH, and citrate levels and increased calcium. Citrate, an important inhibitor of calcium-containing stones, binds with urinary calcium reducing the amount of calcium available to form stones. Citrate inhibits renal stone recurrence by preventing crystal growth, aggregation, and nucleation and is one of the most common therapeutic agents used to prevent stone formation. Methods: Thirty long duration crewmembers (29 male, 1 female) participated in this study. 24-hour urines were collected and dietary monitoring was performed pre, in, and postflight. Crewmembers in the treatment group received two potassium citrate (KCIT) pills, 10 mEq/pill, ingested daily beginning 3 days before launch, all inflight days and through 14 days postflight. Urinary biochemical and dietary analyses were completed. Results: KCIT treated subjects exhibited decreased urinary calcium excretion and maintained the levels of calcium oxalate supersaturation risk at their preflight levels. The increased urinary pH levels in these subjects reduced the risk of uric acid stones. Discussion: The current study investigated the use of potassium citrate as a countermeasure to minimize the risk of stone formation during ISS missions. Results suggest that

  15. Citrate Accumulation-Related Gene Expression and/or Enzyme Activity Analysis Combined With Metabolomics Provide a Novel Insight for an Orange Mutant

    PubMed Central

    Guo, Ling-Xia; Shi, Cai-Yun; Liu, Xiao; Ning, Dong-Yuan; Jing, Long-Fei; Yang, Huan; Liu, Yong-Zhong

    2016-01-01

    ‘Hong Anliu’ (HAL, Citrus sinensis cv. Hong Anliu) is a bud mutant of ‘Anliu’ (AL), characterized by a comprehensive metabolite alteration, such as lower accumulation of citrate, high accumulation of lycopene and soluble sugars in fruit juice sacs. Due to carboxylic acid metabolism connects other metabolite biosynthesis and/or catabolism networks, we therefore focused analyzing citrate accumulation-related gene expression profiles and/or enzyme activities, along with metabolic fingerprinting between ‘HAL’ and ‘AL’. Compared with ‘AL’, the transcript levels of citrate biosynthesis- and utilization-related genes and/or the activities of their respective enzymes such as citrate synthase, cytosol aconitase and ATP-citrate lyase were significantly higher in ‘HAL’. Nevertheless, the mitochondrial aconitase activity, the gene transcript levels of proton pumps, including vacuolar H+-ATPase, vacuolar H+-PPase, and the juice sac-predominant p-type proton pump gene (CsPH8) were significantly lower in ‘HAL’. These results implied that ‘HAL’ has higher abilities for citrate biosynthesis and utilization, but lower ability for the citrate uptake into vacuole compared with ‘AL’. Combined with the metabolites-analyzing results, a model was then established and suggested that the reduction in proton pump activity is the key factor for the low citrate accumulation and the comprehensive metabolite alterations as well in ‘HAL’. PMID:27385485

  16. Plasma membrane H-ATPase-dependent citrate exudation from cluster roots of phosphate-deficient white lupin.

    PubMed

    Tomasi, Nicola; Kretzschmar, Tobias; Espen, Luca; Weisskopf, Laure; Fuglsang, Anja Thoe; Palmgren, Michael Gjedde; Neumann, Günter; Varanini, Zeno; Pinton, Roberto; Martinoia, Enrico; Cesco, Stefano

    2009-05-01

    White lupin (Lupinus albus L.) is able to grow on soils with sparingly available phosphate (P) by producing specialized structures called cluster roots. To mobilize sparingly soluble P forms in soils, cluster roots release substantial amounts of carboxylates and concomitantly acidify the rhizosphere. The relationship between acidification and carboxylate exudation is still largely unknown. In the present work, we studied the linkage between organic acids (malate and citrate) and proton exudations in cluster roots of P-deficient white lupin. After the illumination started, citrate exudation increased transiently and reached a maximum after 5 h. This effect was accompanied by a strong acidification of the external medium and alkalinization of the cytosol, as evidenced by in vivo nuclear magnetic resonance (NMR) analysis. Fusicoccin, an activator of the plasma membrane (PM) H+-ATPase, stimulated citrate exudation, whereas vanadate, an inhibitor of the H+-ATPase, reduced citrate exudation. The burst of citrate exudation was associated with an increase in expression of the LHA1 PM H+-ATPase gene, an increased amount of H+-ATPase protein, a shift in pH optimum of the enzyme and post-translational modification of an H+-ATPase protein involving binding of activating 14-3-3 protein. Taken together, our results indicate a close link in cluster roots of P-deficient white lupin between the burst of citrate exudation and PM H+-ATPase-catalysed proton efflux.

  17. High-throughput and rapid fluorescent visualization sensor of urinary citrate by CdTe quantum dots.

    PubMed

    Zhuo, Shujuan; Gong, Jiajia; Zhang, Ping; Zhu, Changqing

    2015-08-15

    In this paper, we have presented a novel CdTe quantum dots (QDs) based fluorescent sensor for visual and turn-on sensing of citrate in human urine samples. The europium ion (Eu(3+)) can lead to the fluorescence quenching of thioglycollic acid (TGA) modified CdTe QDs due to photoinduced electron transfer accompanied by the change of emission color from yellow to orange. Next, addition of citrate breaks the preformed assembly because citrate can replace the CdTe QDs, based on the fact that the Eu(3+) ion displays higher affinity with citrate than the CdTe QDs. Thus the photoinduced electron transfer is switched off, and the fluorescence emission of CdTe QDs is rapidly (within 5min) recovered, simultaneously, the orange emission color restores to yellow. Such proposed strategy may conveniently discriminate the patient of renal stone from normal person by naked eyes. In addition to visualization detection, the fluorescence responses can be used for well quantifying citrate in the range of 0.67-133μM. So, the present, simple, low-cost and visualized citrate fluorescence sensor has great potential in the applications for earlier screening in clinical detection.

  18. Plasma Citrate Homeostasis: How It Is Regulated; And Its Physiological and Clinical Implications. An Important, But Neglected, Relationship in Medicine

    PubMed Central

    Costello, Leslie C; Franklin, Renty B

    2017-01-01

    The homeostatic maintenance of a normal plasma citrate concentration is an important factor in humans and in animals; and is required for many normal physiological activities. Dysregulation of normal plasma citrate presents pathophysiological hypocitricemic or hypercitricemic conditions. This can lead to clinical consequences in many areas of medicine; such as impaired blood clotting, altered acid/base status, impaired neuromuscular/cardiac activities, hypocitraturia and stone formation, bone disorders with loss of bone strength and increased fractures, hypocitricemia of surgical stress. These important implications of citrate relationships have been largely ignored by the contemporary clinical and biomedical community; to the extent that it is not even described in most current textbooks and review papers. This review describes the physiological, endocrine, and metabolic relationships in the normal regulation and maintenance of plasma citrate; and presents some important clinical consequences of its dysfunctional maintenance. The importance of bone, kidney and liver activities in the maintenance of normal plasma citrate is described along with the citricemic roles of parathyroid hormone, calcitonin and vitamin D. These factors and relationships are presented as the contemporary understanding of the integrated regulation of plasma citrate as the basis for its clinical importance in medicine. The exclusion of these citrate relationships leads to misunderstanding and misrepresentation of physiological and clinical conditions in many issues in medicine and paramedicine areas. The intent of this review is to revive the interest and support for research to address the many unknown and speculative issues of plasma citrate regulation and its important clinical implications. This is in the best interest of the medical community and the public-at-large. PMID:28286881

  19. Cloning and nucleotide sequence of the gene (citA) encoding a citrate carrier from Salmonella typhimurium.

    PubMed

    Shimamoto, T; Izawa, H; Daimon, H; Ishiguro, N; Shinagawa, M; Sakano, Y; Tsuda, M; Tsuchiya, T

    1991-07-01

    A cryptic citrate transport gene (citA) from Salmonella typhimurium chromosome was cloned and its nucleotide sequence was determined. The cloned plasmid conferred citrate-utilizing ability on wild-type Escherichia coli, which cannot grow on citrate as the sole source of carbon. The resultant E. coli transformant was able to transport citrate. A 1,302-base-pair open reading frame with a preceding ribosomal binding site was found in the cloned DNA fragment. The 434-amino-acid protein that could be translated from this open reading frame is highly hydrophobic (69% nonpolar amino acid residues), consistent with the fact that the transport protein is an intrinsic membrane protein. The molecular weight of this protein was calculated to be 47,188. The gene sequence determined is highly homologous to those of Cit+ plasmid-mediated citrate transport gene, citA, from E. coli, the chromosomal citA gene from Citrobacter amalonaticus and the chromosomal cit+ gene from Klebsiella pneumoniae. The hydropathy profile of the deduced amino acid sequence suggests that this carrier has 12 hydrophobic segments, which may span the membrane lipid bilayer.

  20. Endoscopic Treatment of Bleeding Diversion Pouchitis with High-Concentration Dextrose Spray

    PubMed Central

    Nyabanga, Custon T.

    2017-01-01

    Surgical closure of stoma with the reestablishment of gut continuity is the only curative intervention available for inflammatory bowel disease patients with diversion pouchitis, proctitis, or colitis. For patients who are not candidates for surgical reestablishment of bowel continuity, the alternative nonsurgical approaches, such as topical therapy with mesalamine, corticosteroids, or short-chain fatty acids, have only shown modest efficacy. The management of massive bleeding from diversion pouchitis has not been described. We present a patient with ulcerative colitis with severe hematochezia and diffuse mucosal bleeding in a diverted ileal pouch, which was successfully treated with endoscopic spray of hypertonic glucose. PMID:28377939

  1. (13)C heteronuclear NMR studies of the interaction of cultured neurons and astrocytes and aluminum blockade of the preferential release of citrate from astrocytes.

    PubMed

    Meshitsuka, Shunsuke; Aremu, David A

    2008-02-01

    Citrate has been identified as a major tricarboxylic acid (TCA) cycle constituent preferentially released by astrocytes. We undertook the present study to examine further the nature of metabolic compartmentation in central nervous system tissues using (13)C-labeled glucose and to provide new information on the influence of aluminum on the metabolic interaction between neurons and astrocytes. Metabolites released into the culture medium from astrocytes and neuron-astrocyte coculture, as well as the perchloric acid extracts of the cells were analyzed using 2D (1)H and (13)C NMR spectroscopy. Astrocytes released citrate into the culture medium and the released citrate was consumed by neurons in coculture. Citrate release by astrocytes was blocked in the presence of aluminum, with progressive accumulation of citrate within the cells. We propose citrate supply is a more efficient energy source than lactate for neurons to produce ATP, especially in the hypoglycemic state on account of it being a direct component of the TCA cycle. Astrocytes may be the cellular compartment for aluminum accumulation as a citrate complex in the brain.

  2. Assembly of citrate gold nanoparticles on hydrophilic monolayers

    NASA Astrophysics Data System (ADS)

    Vikholm-Lundin, Inger; Rosqvist, Emil; Ihalainen, Petri; Munter, Tony; Honkimaa, Anni; Marjomäki, Varpu; Albers, Willem M.; Peltonen, Jouko

    2016-08-01

    Self-assembled monolayers (SAMs) as model surfaces were linked onto planar gold films thorough lipoic acid or disulfide groups. The molecules used were polyethylene glycol (EG-S-S), N-[tris-(hydroxymethyl)methyl]acrylamide polymers with and without lipoic acid (Lipa-pTHMMAA and pTHMMAA) and a lipoic acid triazine derivative (Lipa-MF). All the layers, but Lipa-MF with a primary amino group were hydroxyl terminated. The layers were characterized by contact angle measurements and atomic force microscopy, AFM. Citrate stabilized nanoparticles, AuNPs in water and phosphate buffer were allowed to assemble on the layers for 10 min and the binding was followed in real-time with surface plasmon resonance, SPR. The SPR resonance curves were observed to shift to higher angles and become increasingly damped, while also the peaks strongly broaden when large nanoparticles assembled on the surface. Both the angular shift and the damping of the curve was largest for nanoparticles assembling on the EG-S-S monolayer. High amounts of particles were also assembled on the pTHMMAA layer without the lipoic acid group, but the damping of the curve was considerably lower with a more even distribution of the particles. Topographical images confirmed that the highest number of particles were assembled on the polyethylene glycol monolayer. By increasing the interaction time more particles could be assembled on the surface.

  3. Cloning and characterization of the citA gene encoding the mitochondrial citrate synthase of Aspergillus nidulans.

    PubMed

    Park, B W; Han, K H; Lee, C Y; Lee, C H; Maeng, P J

    1997-04-30

    We isolated a citrate synthase gene (citA) from Aspergillus nidulans. By analysis of the protein coding region, citA was shown to encode a citrate synthase (CitA) of 52.2 kDa consisting of 474 amino acid residues that were interrupted by seven introns. Also, the precursor CitA protein was revealed to have an N-terminal mitochondrial targeting signal of 35 amino acid residues containing an R-3 cleavage motif, R(32)-C-Y decreases S(35), which supports the fact that citA encodes the mitochondrial form of citrate synthase of A. nidulans. Southern blot analysis showed that citA is present as a single copy in the genome.

  4. Citrate metabolism in blood transfusions and its relationship due to metabolic alkalosis and respiratory acidosis

    PubMed Central

    Li, Kai; Xu, Yuan

    2015-01-01

    Metabolic alkalosis commonly results from excessive hydrochloric acid (HCl), potassium (K+) and water (H2O) loss from the stomach or through the urine. The plasma anion gap increases in non-hypoproteinemic metabolic alkalosis due to an increased negative charge equivalent on albumin and the free ionized calcium (Ca++) content of plasma decreases. The mean citrate load in all patients was 8740±7027 mg from 6937±6603 mL of transfused blood products. The citrate load was significantly higher in patients with alkalosis (9164±4870 vs. 7809±3967, P < 0.05). The estimated mean total citrate administered via blood and blood products was calculated as 43.2±34.19 mg/kilogram/day. In non-massive and frequent blood transfusions, the elevated carbon dioxide output has been shown to occur. Due to citrate metabolism causes intracellular acidosis. As a result of intracellular acidosis compensation, decompensated metabolic alkalosis + respiratory acidosis and electrolyte imbalance may develop, blood transfusions may result in certain complications. PMID:26131288

  5. Brassica oleracea MATE encodes a citrate transporter and enhances aluminum tolerance in Arabidopsis thaliana.

    PubMed

    Wu, Xinxin; Li, Ren; Shi, Jin; Wang, Jinfang; Sun, Qianqian; Zhang, Haijun; Xing, Yanxia; Qi, Yan; Zhang, Na; Guo, Yang-Dong

    2014-08-01

    The secretion of organic acid anions from roots is an important mechanism for plant aluminum (Al) tolerance. Here we report cloning and characterizing BoMATE (KF031944), a multidrug and toxic compound extrusion (MATE) family gene from cabbage (Brassica oleracea). The expression of BoMATE was more abundant in roots than in shoots, and it was highly induced by Al treatment. The (14)C-citrate efflux experiments in oocytes demonstrated that BoMATE is a citrate transporter. Electrophysiological analysis and SIET analysis of Xenopus oocytes expressing BoMATE indicated BoMATE is activated by Al. Transient expression of BoMATE in onion epidermal cells demonstrated that it localized to the plasma membrane. Compared with the wild-type Arabidopsis, the transgenic lines constitutively overexpressing BoMATE enhanced Al tolerance and increased citrate secretion. In addition, Arabidopsis transgenic lines had a lower K(+) efflux and higher H(+) efflux, in the presence of Al, than control wild type in the distal elongation zone (DEZ). This is the first direct evidence that MATE protein is involved in the K(+) and H(+) flux in response to Al treatment. Taken together, our results show that BoMATE is an Al-induced citrate transporter and enhances aluminum tolerance in Arabidopsis thaliana.

  6. Sildenafil citrate for female sexual arousal disorder: a future possibility?

    PubMed

    Schoen, Corina; Bachmann, Gloria

    2009-04-01

    Female sexual arousal disorder (FSAD) is a common disorder encountered in clinical practice, with self-reported arousal difficulties reported in up to 26% of American women. Various oral therapies for FSAD have been studied, including sildenafil citrate, a phosphodiesterase inhibitor that is currently used to treat male erectile dysfunction. In vitro studies of sildenafil citrate have demonstrated smooth-muscle relaxation in clitoral tissue, and phosphodiesterase type-5 has been shown to be present in vaginal, clitoral and labial smooth muscle; these findings have led to theories that sildenafil citrate might be successful for treating FSAD. This Review discusses the data from clinical trials that have assessed sildenafil citrate for the treatment of FSAD; the trials show that sildenafil citrate is moderately effective. Sildenafil citrate may also be effective in women with FSAD secondary to multiple sclerosis, diabetes or antidepressant use; however, more trials in these patient populations are required to confirm these findings.

  7. Citrate in plasma and urine during total fasting.

    PubMed

    Nielsen, T T; Sørensen, N S

    1979-01-01

    Plasma citrate was determined in 12 obese subjects who underwent total fasting for 10 days. Mean plasma citrate concentration rose significantly from 128 before to 205 micro mol/1 on the 10th day of fasting. Plasma citrate rose continuously during fasting in seven subjects in whom daily determinations were carried out. The 24-hour urinary citrate excretion was followed in six subjects. A significant decrease was found from 2.91 mmol/24 h in the prefasting state to 0.25 mmol/24 h at the end of the fast. Intravenous glucose tolerance test were performed before and on the 10th day of fasting. Kivgtt decreased significantly and was inversely related to plasma citrate concentration on the 10th day of fasting. The results agree well with the concept that an increased citrate level of tissues is of regulatory importance for the decreased glucose utilization during fasting in man.

  8. SbnG, a Citrate Synthase in Staphylococcus aureus

    PubMed Central

    Kobylarz, Marek J.; Grigg, Jason C.; Sheldon, Jessica R.; Heinrichs, David E.; Murphy, Michael E. P.

    2014-01-01

    In response to iron deprivation, Staphylococcus aureus produces staphyloferrin B, a citrate-containing siderophore that delivers iron back to the cell. This bacterium also possesses a second citrate synthase, SbnG, that is necessary for supplying citrate to the staphyloferrin B biosynthetic pathway. We present the structure of SbnG bound to the inhibitor calcium and an active site variant in complex with oxaloacetate. The overall fold of SbnG is structurally distinct from TCA cycle citrate synthases yet similar to metal-dependent class II aldolases. Phylogenetic analyses revealed that SbnG forms a separate clade with homologs from other siderophore biosynthetic gene clusters and is representative of a metal-independent subgroup in the phosphoenolpyruvate/pyruvate domain superfamily. A structural superposition of the SbnG active site to TCA cycle citrate synthases and site-directed mutagenesis suggests a case for convergent evolution toward a conserved catalytic mechanism for citrate production. PMID:25336653

  9. Prophylactic Oral Dextrose Gel for Newborn Babies at Risk of Neonatal Hypoglycaemia: A Randomised Controlled Dose-Finding Trial (the Pre-hPOD Study)

    PubMed Central

    Hegarty, Joanne Elizabeth; Harding, Jane Elizabeth; Gamble, Gregory David; Crowther, Caroline Anne; Edlin, Richard; Alsweiler, Jane Marie

    2016-01-01

    Background Neonatal hypoglycaemia is common, affecting up to 15% of newborns, and can cause brain damage. Currently, there are no strategies, beyond early feeding, to prevent neonatal hypoglycaemia. Our aim was to determine a dose of 40% oral dextrose gel that will prevent neonatal hypoglycaemia in newborn babies at risk. Methods and Findings We conducted a randomised, double-blind, placebo-controlled dose-finding trial of buccal dextrose gel to prevent neonatal hypoglycaemia at two hospitals in New Zealand. Babies at risk of hypoglycaemia (infant of a mother with diabetes, late preterm delivery, small or large birthweight, or other risk factors) but without indication for admission to a neonatal intensive care unit (NICU) were randomly allocated either to one of four treatment groups: 40% dextrose at one of two doses (0.5 ml/kg = 200 mg/kg, or 1 ml/kg = 400 mg/kg), either once at 1 h of age or followed by three additional doses of dextrose (0.5 ml/kg before feeds in the first 12 h); or to one of four corresponding placebo groups. Treatments were administered by massaging gel into the buccal mucosa. The primary outcome was hypoglycaemia (<2.6 mM) in the first 48 h. Secondary outcomes included admission to a NICU, admission for hypoglycaemia, and breastfeeding at discharge and at 6 wk. Prespecified potential dose limitations were tolerance of gel, time taken to administer, messiness, and acceptability to parents. From August 2013 to November 2014, 416 babies were randomised. Compared to babies randomised to placebo, the risk of hypoglycaemia was lowest in babies randomised to a single dose of 200 mg/kg dextrose gel (relative risk [RR] 0.68; 95% confidence interval [CI] 0.47–0.99, p = 0.04) but was not significantly different between dose groups (p = 0.21). Compared to multiple doses, single doses of gel were better tolerated, quicker to administer, and less messy, but these limitations were not different between dextrose and placebo gel groups. Babies who received

  10. Enrofloxacinium citrate monohydrate: Preparation, crystal structure, thermal stability and IR-characterization

    NASA Astrophysics Data System (ADS)

    Golovnev, Nicolay N.; Vasiliev, Alexander D.; Kirik, Sergei D.

    2012-08-01

    Enrofloxacinium citrate monohydrate (I), CHFNO3+·CHO7-·HO, [C19H22FN3O3 - enrofloxacin, EnrH] has been crystallized from the mutual solution of citric acid and enrofloxacin in ambient conditions. The colorless crystals have been investigated using X-ray single crystal and powder techniques, and characterized by differential scanning calorimetry, thermogravimetry and infrared spectroscopy. The obtained compound can be considered as a salt with enrofloxacinium in the role of a cation and citrate as an anion. The ions ratio equals to 1:1. The compound crystallizes in the triclinic lattice with a = 9.0489(8) Å, b = 9.6531(8) Å, c = 14.913(1) Å, α = 98.813(1)°, β = 92.029(1)°, γ = 91.013(1)°, Z = 2, V = 1286.1(2) Å3, S.G. P1¯. The crystal structure determination reveals the importance of inter- and intramolecular interactions in the crystal formation. The EnrH2+ and HCit molecular ions are packed in alternating layers with water molecules inserted into the citrate layers. A citrate ion in the layer is linked via H-bondings with two adjacent ones and three water molecules. Enrofloxacinium cations are packaged by means of a benched mode and every cation is linked by three intermolecular thymus type H-bondings with nitrogens of adjacent cations and by two links with the oxygen of the citrate ions. The infrared spectra gave the evidence of H-bonding formation in the obtained salt. The π-stacking interactions are observed between the aromatic cycles of the adjacent cations which are located in an antiparallel style in a layer.

  11. Combined effect of γ-irradiation and bacterial-fermented dextrose on microbiological quality of refrigerated pork sausages

    NASA Astrophysics Data System (ADS)

    Dussault, D.; Benoit, C.; Lacroix, M.

    2012-08-01

    The objective of this study was to evaluate the effect of a concentrated fermented dextrose (FD), a natural antimicrobial product, combined with low dose γ-irradiation (1.5 kGy) on the microbiological quality of fresh pork sausages. Fresh pork sausages containing the FD (0.25%, 0.5% and 0.75%) were prepared in a meat pilot plant and were irradiated using a UC-15A irradiator equipped with a 60Cobalt source. The γ-irradiation treatment alone was able to reduce the initial psychrophilic and mesophilic bacteria by more than 2 log CFU/g and kept the lactobacillus population under the detection limit (100 CFU/g). Results also showed that the FD alone was able to extend the shelf life of the sausages from 5 days up to 13 days. At day 13, the FD or irradiation alone showed 2 log CFU/g less mesophilic bacteria than the control. After combining FD and irradiation another reduction of the microbial count of 1 log CFU/g was observed. When combining the irradiation treatment with the FD results it showed a reduced growth rate of the psychrophilic and mesophilic bacteria compared to both treatments alone. This study demonstrated that FD with low dose gamma irradiation act in synergy to reduce the multiplication of the total bacterial flora in fresh sausages.

  12. Citraturic response to oral citric acid load

    NASA Technical Reports Server (NTRS)

    Sakhaee, K.; Alpern, R.; Poindexter, J.; Pak, C. Y.

    1992-01-01

    It is possible that some orally administered citrate may appear in urine by escaping oxidation in vivo. To determine whether this mechanism contributes to the citraturic response to potassium citrate, we measured serum and urinary citrate for 4 hours after a single oral load of citric acid (40 mEq.) in 6 normal subjects. Since citric acid does not alter acid-base balance, the effect of absorbed citrate could be isolated from that of alkali load. Serum citrate concentration increased significantly (p less than 0.05) 30 minutes after a single oral dose of citric acid and remained significantly elevated for 3 hours after citric acid load. Commensurate with this change, urinary citrate excretion peaked at 2 hours and gradually decreased during the next 2 hours after citric acid load. In contrast, serum and urinary citrate remained unaltered following the control load (no drug). Differences of the citratemic and citraturic effects between phases were significant (p less than 0.05) at 2 and 3 hours. Urinary pH, carbon dioxide pressure, bicarbonate, total carbon dioxide and ammonium did not change at any time after citric acid load, and did not differ between the 2 phases. No significant difference was noted in serum electrolytes, arterialized venous pH and carbon dioxide pressure at any time after citric acid load and between the 2 phases. Thus, the citraturic and citratemic effects of oral citric acid are largely accountable by provision of absorbed citrate, which has escaped in vivo degradation.

  13. Na/K citrate versus sodium bicarbonate in prevention of contrast-induced nephropathy.

    PubMed

    Abouzeid, Sameh Mohamed; ElHossary, Hossam E

    2016-05-01

    Contrast-induced nephropathy (CIN) is one of the important complications of radiographic procedures, especially in patients with chronic kidney disease. It is also one of the common causes of acute kidney injury. The pathogenesis is postulated to be the effect of oxygen- free radicals and hyperosmolar stress on the renal medulla. It is reported that the production of superoxide is most active at acid environment. K/Na citrate is well known as a urine alkalinization medium, and this has been evaluated earlier with standard hydration for reduction of CIN and was stated to be efficient. We aimed to determine the efficacy of Na/K citrate in reducing the frequency of CIN in comparison to sodium bicarbonate in patients after coronary angiography. Two hundred and ten patients with renal dysfunction [estimated glomerular filtration rate (eGFR), 60 mL/min/1.73 m(2) or less] who underwent elective or emergency coronary angiography (CAG) with/without percutaneous coronary intervention (PCI) at our institution were enrolled into the study. The patients were randomized into two groups, Group 1-Taking Na/K citrate and Group 2-Taking sodium bicarbonate. Radiographic contrast agent iohexol was used. Change in creatinine, percent change in creatinine, percent change in eGFR, change in serum potassium, and urine pH were all compared between the two groups. There was no significant difference for prevention of CIN when comparing the Na/K citrate with sodium bicarbonate solution in patients exposed to CAG with or without PCI. Mean absolute change in eGFR after 48 h after administration of contrast between sodium bicarbonate group and Na/K citrate group was -0.60 ± 1.58 versus -0.71 ± 1.38. Serum potassium decreased postprocedure in the sodium bicarbonate group than in the citrate group (3.90 ± 0.33 vs. 4.14 ± 0.39). Both agents are equally effective in reducing the incidence of CIN, but the citrate would possibly be a safer option for patients at risk of hypokalemia.

  14. Title A de novo synthesis citrate transporter VuMATE confers aluminum resistance in rice bean (vigna umbellata)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Al-activated organic acid anion efflux from roots is an important Al resistance mechanism in plants. We have conducted the homologous cloning and isolation of VuMATE (Vigna umbellata multidrug and toxic compound extrusion), a gene encoding a de novo citrate transporter from rice bean. Al treatment u...

  15. Optimalization of Poly(neutral red) Coated-wire Electrode for Determination of Citrate in Soft Drinks.

    PubMed

    Broncová, Gabriela; Shishkanova, Tatiana V; Krondak, Martin; Volf, Radko; Král, Vladimír

    2008-02-04

    This report presents an optimization of potentiometric measurements withcitrate-selective electropolymerized poly(neutral red) electrodes. The optimal backgroundelectrolyte for these measurements is a TRIS buffer with nitrate at pH 8.5. The electrodesdescribed here exhibit stable and reproducible near-Nernstian response to citrates with alow detection limit of 6 × 10(-6) M. Electrodes polymerized from sulfuric acid andacetonitrile are compared in detail. Simple and sensitive method for quantification ofcitrate in real-life samples by potentiometry with poly(neutral red) electrodes arepresented. Data from potentiometric measurements of citrate are compared with capillaryelectrophoresis.

  16. The distribution of plasmids determining citrate utilization in citrate-positive variants of Escherichia coli from humans, domestic animals, feral birds and environments.

    PubMed

    Ishiguro, N; Sato, G

    1979-10-01

    Sixty-seven isolates of citrate-positive variants of Escherichia coli were isolated from human, domestic animal, feral bird and environmental sources. With the exception of citrate utilization, all isolates were identified as typical E. coli by their biochemical reactions. The transmission of the ability to utilize citrate on Simmons' citrate agar was demonstrated in 53 (79.1%) out of the 67 citrate-positive E. coli variants obtained from various sources. Drug resistance determinants and citrate utilizing character were co-transmitted into E. coli K-12 by conjugation among citrate-positive E. coli isolates carrying R plasmids except for that isolated from horses. The other characters (haemolysin or colicin production, raffinose or sucrose fermentation) were not transmitted together with the citrate utilizing character. These facts suggested that the structural gene responsible for citrate utilizing ability in citrate-positive variants of E. coli was located on a conjugative plasmid.

  17. 21 CFR 73.1025 - Ferric ammonium citrate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 1 2011-04-01 2011-04-01 false Ferric ammonium citrate. 73.1025 Section 73.1025 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1025 Ferric ammonium citrate. (a) Identity....

  18. 21 CFR 73.1025 - Ferric ammonium citrate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 1 2014-04-01 2014-04-01 false Ferric ammonium citrate. 73.1025 Section 73.1025 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1025 Ferric ammonium citrate. (a) Identity....

  19. 21 CFR 73.1025 - Ferric ammonium citrate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 1 2013-04-01 2013-04-01 false Ferric ammonium citrate. 73.1025 Section 73.1025 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1025 Ferric ammonium citrate. (a) Identity....

  20. 21 CFR 73.1025 - Ferric ammonium citrate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 1 2012-04-01 2012-04-01 false Ferric ammonium citrate. 73.1025 Section 73.1025 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1025 Ferric ammonium citrate. (a) Identity....

  1. 21 CFR 73.1025 - Ferric ammonium citrate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Ferric ammonium citrate. 73.1025 Section 73.1025 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1025 Ferric ammonium citrate. (a) Identity....

  2. Characterization of ATP citrate lyase from Chlorobium limicola.

    PubMed Central

    Antranikian, G; Herzberg, C; Gottschalk, G

    1982-01-01

    ATP citrate lyase (EC 4.1.3.8) from Chlorobium limicola was partially purified. It was established that the consumption of substrates and the formation of products proceeded stoichiometrically and that citrate cleavage was of the si-type. ADP and oxaloacetate inhibited enzyme activity. Oxaloacetate also inhibited the growth of C. limicola. PMID:7142107

  3. Enhanced dissolution of sildenafil citrate as dry foam tablets.

    PubMed

    Sawatdee, Somchai; Atipairin, Apichart; Sae Yoon, Attawadee; Srichana, Teerapol; Changsan, Narumon

    2017-01-30

    Dry foam formulation technology is alternative approach to enhance dissolution of the drug. Sildenafil citrate was suspended in sodium dodecyl sulfate solution and adding a mixture of maltodextrin and mannitol as diluent to form a paste. Sildenafil citrate paste was passed through a nozzle spray bottle to obtain smooth foam. The homogeneous foam was dried in a vacuum oven and sieved to obtain dry foam granules. The granules were mixed with croscarmellose sodium, magnesium stearate and compressed into tablet. All formulations were evaluated for their physicochemical properties and dissolution profiles. All the tested excipients were compatible with sildenafil citrate by both differential scanning calorimetry (DSC) and infrared (IR) analysis. There are no X-ray diffraction (XRD) peaks representing crystals of sildenafil citrate observed form dry foam formulations. The hardness of tablets was about 5 kg, friability test <1% with a disintegration time <5 min. The sildenafil citrate dry foam tablet had higher dissolution rate in 0.1 N HCl in comparison with commercial sildenafil citrate tablet, sildenafil citrate prepared by direct compression and wet granulation method. Sildenafil citrate dry foam tablet with the high-level composition of surfactant, water and diluent showed enhanced dissolution rate than that of the lower-level composition of these excipients. This formulation was stable under accelerated conditions for at least 6 months.

  4. Diffuse abdominal gallium-67 citrate uptake in salmonella infections

    SciTech Connect

    Garty, I.; Koren, A.

    1987-11-01

    Two pediatric patients with salmonella infections (one with typhoid fever and the second with salmonella C2 gastroenteritis), had a diffuse abdominal uptake of Ga-67 citrate. The possible explanation for this finding is discussed. Salmonella infection should be included as a cause in the differential diagnosis of diffuse accumulation of Ga-67 citrate.

  5. Structural basis for norovirus inhibition and fucose mimicry by citrate.

    PubMed

    Hansman, Grant S; Shahzad-Ul-Hussan, Syed; McLellan, Jason S; Chuang, Gwo-Yu; Georgiev, Ivelin; Shimoike, Takashi; Katayama, Kazuhiko; Bewley, Carole A; Kwong, Peter D

    2012-01-01

    Human noroviruses bind with their capsid-protruding domains to histo-blood-group antigens (HBGAs), an interaction thought to direct their entry into cells. Although human noroviruses are the major cause of gastroenteritis outbreaks, development of antivirals has been lacking, mainly because human noroviruses cannot be cultivated. Here we use X-ray crystallography and saturation transfer difference nuclear magnetic resonance (STD NMR) to analyze the interaction of citrate with genogroup II (GII) noroviruses. Crystals of citrate in complex with the protruding domain from norovirus GII.10 Vietnam026 diffracted to 1.4 Å and showed a single citrate bound at the site of HBGA interaction. The citrate interaction was coordinated with a set of capsid interactions almost identical to that involved in recognizing the terminal HBGA fucose, the saccharide which forms the primary conserved interaction between HBGAs and GII noroviruses. Citrate and a water molecule formed a ring-like structure that mimicked the pyranoside ring of fucose. STD NMR showed the protruding domain to have weak affinity for citrate (460 μM). This affinity, however, was similar to the affinities of the protruding domain for fucose (460 μM) and H type 2 trisaccharide (390 μM), an HBGA shown previously to be specifically recognized by human noroviruses. Importantly, competition STD NMR showed that citrate could compete with HBGA for norovirus binding. Together, the results suggest that citrate and other glycomimetics have the potential to block human noroviruses from binding to HBGAs.

  6. Structural Basis for Norovirus Inhibition and Fucose Mimicry by Citrate

    SciTech Connect

    Hansman, Grant S.; Shahzad-ul-Hussan, Syed; McLellan, Jason S.; Chuang, Gwo-Yu; Georgiev, Ivelin; Shimoike, Takashi; Katayama, Kazuhiko; Bewley, Carole A.; Kwong, Peter D.

    2012-01-20

    Human noroviruses bind with their capsid-protruding domains to histo-blood-group antigens (HBGAs), an interaction thought to direct their entry into cells. Although human noroviruses are the major cause of gastroenteritis outbreaks, development of antivirals has been lacking, mainly because human noroviruses cannot be cultivated. Here we use X-ray crystallography and saturation transfer difference nuclear magnetic resonance (STD NMR) to analyze the interaction of citrate with genogroup II (GII) noroviruses. Crystals of citrate in complex with the protruding domain from norovirus GII.10 Vietnam026 diffracted to 1.4 {angstrom} and showed a single citrate bound at the site of HBGA interaction. The citrate interaction was coordinated with a set of capsid interactions almost identical to that involved in recognizing the terminal HBGA fucose, the saccharide which forms the primary conserved interaction between HBGAs and GII noroviruses. Citrate and a water molecule formed a ring-like structure that mimicked the pyranoside ring of fucose. STD NMR showed the protruding domain to have weak affinity for citrate (460 {mu}M). This affinity, however, was similar to the affinities of the protruding domain for fucose (460 {mu}M) and H type 2 trisaccharide (390 {mu}M), an HBGA shown previously to be specifically recognized by human noroviruses. Importantly, competition STD NMR showed that citrate could compete with HBGA for norovirus binding. Together, the results suggest that citrate and other glycomimetics have the potential to block human noroviruses from binding to HBGAs.

  7. 21 CFR 520.622 - Diethylcarbamazine citrate oral dosage forms.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Diethylcarbamazine citrate oral dosage forms. 520.622 Section 520.622 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... Diethylcarbamazine citrate oral dosage forms....

  8. 21 CFR 520.622 - Diethylcarbamazine citrate oral dosage forms.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Diethylcarbamazine citrate oral dosage forms. 520.622 Section 520.622 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... Diethylcarbamazine citrate oral dosage forms....

  9. 21 CFR 520.622 - Diethylcarbamazine citrate oral dosage forms.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Diethylcarbamazine citrate oral dosage forms. 520.622 Section 520.622 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... Diethylcarbamazine citrate oral dosage forms....

  10. 21 CFR 520.622 - Diethylcarbamazine citrate oral dosage forms.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Diethylcarbamazine citrate oral dosage forms. 520.622 Section 520.622 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... Diethylcarbamazine citrate oral dosage forms....

  11. Injectable citrate-modified Portland cement for use in vertebroplasty.

    PubMed

    Wynn-Jones, Gareth; Shelton, Richard M; Hofmann, Michael P

    2014-11-01

    The injectability of Portland cement (PC) with several citrate additives was investigated for use in clinical applications such as vertebroplasty (stabilization of a fractured vertebra with bone cement) using a syringe. A 2-wt % addition of sodium or potassium citrate with PC significantly improved cement injectability, decreased cement setting times from over 2 h to below 25 min, while increasing the compressive strength to a maximum of 125 MPa. Zeta-potential measurements indicated that the citrate anion was binding to one or more of the positively charged species causing charged repulsion between cement particles which dispersed aggregates and caused the liquefying effect of the anion. Analysis of the hydrating phases of PC indicated that the early strength producing PC phase (ettringite) developed within the first 2 h of setting following addition of the citrate anion, while this did not occur in the control cement (PC only). Within 24 h ettringite developed in PC as well as calcium-silicate-hydrate (C-S-H), the major setting phase of PC, whereas cements containing citrate did not develop this phase. The evidence suggested that in the presence of citrate the cements limited water supply appeared to be utilized for ettringite formation, producing the early strength of the citrate cements. The present study has demonstrated that it is possible to modify PC with citrate to both improve the injectability and crucially reduce the setting times of PC while improving the strength of the cement.

  12. Controlling Citrate Synthase Expression by CRISPR/Cas9 Genome Editing for n-Butanol Production in Escherichia coli.

    PubMed

    Heo, Min-Ji; Jung, Hwi-Min; Um, Jaeyong; Lee, Sang-Woo; Oh, Min-Kyu

    2017-02-17

    Genome editing using CRISPR/Cas9 was successfully demonstrated in Esherichia coli to effectively produce n-butanol in a defined medium under microaerobic condition. The butanol synthetic pathway genes including those encoding oxygen-tolerant alcohol dehydrogenase were overexpressed in metabolically engineered E. coli, resulting in 0.82 g/L butanol production. To increase butanol production, carbon flux from acetyl-CoA to citric acid cycle should be redirected to acetoacetyl-CoA. For this purpose, the 5'-untranslated region sequence of gltA encoding citrate synthase was designed using an expression prediction program, UTR designer, and modified using the CRISPR/Cas9 genome editing method to reduce its expression level. E. coli strains with decreased citrate synthase expression produced more butanol and the citrate synthase activity was correlated with butanol production. These results demonstrate that redistributing carbon flux using genome editing is an efficient engineering tool for metabolite overproduction.

  13. Citrate synthesis in intact rat-liver mitochondria is irreversible.

    PubMed

    Greksák, M; Lopes-Cardozo, M; van den Bergh, S G

    1982-02-01

    Rat-liver mitochondria were incubated with [1,5-14C]citrate in the presence of fluorocitrate to block its oxidation in the Krebs cycle. The reaction products were analysed enzymatically and by anion-exchange chromatography. Incorporation of 14C into acetyl-L-carnitine or ketone bodies via a backward action of citrate synthase was not observed. The optimal rate of citrate synthesis from pyruvate and malate in the presence of fluorocitrate was 15 nmol . mg-1 min-1. In the absence of fluorocitrate, but in the presence of malonate, citrate was oxidized to succinate at a rate of 4 nmol . mg-1 . min-1. We conclude that the synthesis of citrate by intact rat liver mitochondria is an irreversible process. The possible mechanism underlying this phenomenon and the consequence for metabolic regulation are discussed.

  14. Stability of acetyl-1-carnitine in 5% dextrose using a high-performance liquid chromatography-mass spectrometry times 2 method.

    PubMed

    Zhang, Yang; Jiang, Hongliang; Hutson, Paul

    2012-01-01

    A stability-indicating high-performance liquid chromatography-mass spectrometry times 2 method was developed to establish the stability of acetyl-l-carnitine dissolved in 5% dextrose in water; quantitation of acetyl-l-carnitine and its hydrolysis product I-carnitine was performed using this method. Acetyl-l-carnitine dissolved in water was stress-degraded at a pH range of 3 to 12, and conversion to l-carnitine was quantified over 18 hours. The method was further validated by stressing the acetyl-l-carnitine solution at 68 degrees C, 82 degrees C, and 90 degrees C for up to 10 days, yielding a temperature-dependent hydrolysis rate constant. Acetyl-l-carnitine solutions were stored at 25 degrees C and 4 degrees C to 8 degrees C for 33 days to validate the kinetics prediction. The liquid chromatography-mass spectrometry times 2 method was sensitive and specific, allowing rapid separation and simultaneous quantitation of acetyl-l-carnitine and l-carnitine. Acetyl-l-carnitine dissolved in aqueous solutions is stable at neutral to acidic pH, but unstable at pH > 9. After 1 hour storage at room temperature, only 72.6% of acetyl-l-carnitine was left at pH 11 and 4.2% left at pH 12. The kinetics relationship between temperature and rate constant was In(k) = -8650.1 /T + 20.344 (r2 = 0.9851) at pH 5.2. The time required to degrade 15% of acetyl-I-carnitine was estimated to be 38 days at 25 degrees C or 234 days at 8 degrees C, and was confirmed with actual storage stability testing. Acetyl-l-carnitine dissolved in water (pH 5.2) at concentrations of 1 and 10 mg/mL was found stable at room temperature or refrigerated for at least 33 days using the established stability-indicating method. Acetyl-l-carnitine solutions are not stable at basic pH. When reconstituted in water, acetyl-l-carnitine is stable for over 30 days at room temperature or under refrigeration.

  15. Binding constant determination of uranyl-citrate complex by ACE using a multi-injection method.

    PubMed

    Zhang, Yiding; Li, Linnan; Huang, Hexiang; Xu, Linnan; Li, Ze; Bai, Yu; Liu, Huwei

    2015-04-01

    The binding constant determination of uranyl with small-molecule ligands such as citric acid could provide fundamental knowledge for a better understanding of the study of uranyl complexation, which is of considerable importance for multiple purposes. In this work, the binding constant of uranyl-citrate complex was determined by ACE. Besides the common single-injection method, a multi-injection method to measure the electrophoretic mobility was also applied. The BGEs used contained HClO4 and NaClO4 , with a pH of 1.98 ± 0.02 and ionic strength of 0.050 mol/L, then citric acid was added to reach different concentrations. The electrophoretic mobilities of the uranyl-citrate complex measured by both of the two methods were consistent, and then the binding constant was calculated by nonlinear fitting assuming that the reaction had a 1:1 stoichiometry and the complex was [(UO2 )(Cit)](-) . The binding constant obtained by the multi-injection method was log K = 9.68 ± 0.07, and that obtained by the single-injection method was log K = 9.73 ± 0.02. The results provided additional knowledge of the uranyl-citrate system, and they demonstrated that compared with other methods, ACE using the multi-injection method could be an efficient, fast, and simple way to determine electrophoretic mobilities and to calculate binding constants.

  16. Synthesis and characterization of biomimetic citrate-based biodegradable composites.

    PubMed

    Tran, Richard T; Wang, Liang; Zhang, Chang; Huang, Minjun; Tang, Wanjin; Zhang, Chi; Zhang, Zhongmin; Jin, Dadi; Banik, Brittany; Brown, Justin L; Xie, Zhiwei; Bai, Xiaochun; Yang, Jian

    2014-08-01

    Natural bone apatite crystals, which mediate the development and regulate the load-bearing function of bone, have recently been associated with strongly bound citrate molecules. However, such understanding has not been translated into bone biomaterial design and osteoblast cell culture. In this work, we have developed a new class of biodegradable, mechanically strong, and biocompatible citrate-based polymer blends (CBPBs), which offer enhanced hydroxyapatite binding to produce more biomimetic composites (CBPBHAs) for orthopedic applications. CBPBHAs consist of the newly developed osteoconductive citrate-presenting biodegradable polymers, crosslinked urethane-doped polyester and poly (octanediol citrate), which can be composited with up to 65 wt % hydroxyapatite. CBPBHA networks produced materials with a compressive strength of 116.23 ± 5.37 MPa comparable to human cortical bone (100-230 MPa), and increased C2C12 osterix gene and alkaline phosphatase gene expression in vitro. The promising results above prompted an investigation on the role of citrate supplementation in culture medium for osteoblast culture, which showed that exogenous citrate supplemented into media accelerated the in vitro phenotype progression of MG-63 osteoblasts. After 6 weeks of implantation in a rabbit lateral femoral condyle defect model, CBPBHA composites elicited minimal fibrous tissue encapsulation and were well integrated with the surrounding bone tissues. The development of citrate-presenting CBPBHA biomaterials and preliminary studies revealing the effects of free exogenous citrate on osteoblast culture shows the potential of citrate biomaterials to bridge the gap in orthopedic biomaterial design and osteoblast cell culture in that the role of citrate molecules has previously been overlooked.

  17. Bioavailability of iron from ferric choline citrate and a ferric copper cobalt choline citrate complex for young pigs.

    PubMed

    Miller, E R; Parsons, M J; Ullrey, D E; Ku, P K

    1981-04-01

    Two experiments were conducted to determine the bioavailability for young pigs of Fe from ferric choline citrate or from a commercial mixture of Fe, Cu and Co choline citrate salts. Relative biological value of Fe from either source with a standard of 100 for FeSO4 x 7H20 was about 140 by both hemoglobin regeneration and Fe retention methods.

  18. Reduced peroxisomal citrate synthase activity increases substrate availability for polyhydroxyalkanoate biosynthesis in plant peroxisomes.

    PubMed

    Tilbrook, Kimberley; Poirier, Yves; Gebbie, Leigh; Schenk, Peer M; McQualter, Richard B; Brumbley, Stevens M

    2014-10-01

    Polyhydroxyalkanoates (PHAs) are bacterial carbon storage polymers used as renewable, biodegradable plastics. PHA production in plants may be a way to reduce industrial PHA production costs. We recently demonstrated a promising level of peroxisomal PHA production in the high biomass crop species sugarcane. However, further production strategies are needed to boost PHA accumulation closer to commercial targets. Through exogenous fatty acid feeding of Arabidopsis thaliana plants that contain peroxisome-targeted PhaA, PhaB and PhaC enzymes from Cupriavidus necator, we show here that the availability of substrates derived from the β-oxidation cycle limits peroxisomal polyhydroxybutyrate (PHB) biosynthesis. Knockdown of peroxisomal citrate synthase activity using artificial microRNA increased PHB production levels approximately threefold. This work demonstrates that reduction of peroxisomal citrate synthase activity may be a valid metabolic engineering strategy for increasing PHA production in other plant species.

  19. Implication of citrate, malate and histidine in the accumulation and transport of nickel in Mesembryanthemum crystallinum and Brassica juncea.

    PubMed

    Amari, Taoufik; Lutts, Stanley; Taamali, Manel; Lucchini, Giorgio; Sacchi, Gian Attilio; Abdelly, Chedly; Ghnaya, Tahar

    2016-04-01

    Citrate, malate and histidine have been involved in many processes including metal tolerance and accumulation in plants. These molecules have been frequently reported to be the potential nickel chelators, which most likely facilitate metal transport through xylem. In this context, we assess here, the relationship between organics acids and histidine content and nickel accumulation in Mesembryanthemum crystallinum and Brassica juncea grown in hydroponic media added with 25, 50 and 100 µM NiCl2. Results showed that M. crystallinum is relatively more tolerant to Ni toxicity than B. juncea. For both species, xylem transport rate of Ni increased with increasing Ni supply. A positive correlation was established between nickel and citrate concentrations in the xylem sap. In the shoot of B. juncea, citric and malic acids concentrations were significantly higher than in the shoot of M. crystallinum. Also, the shoots and roots of B. juncea accumulated much more histidine. In contrast, a higher root citrate concentration was observed in M. crystallinum. These findings suggest a specific involvement of malic and citric acid in Ni translocation and accumulation in M. crystallinum and B. juncea. The high citrate and histidine accumulation especially at 100µM NiCl2, in the roots of M. crystallinum might be among the important factors associated with the tolerance of this halophyte to toxic Ni levels.

  20. Study of Maxwell–Wagner (M–W) relaxation behavior and hysteresis observed in bismuth titanate layered structure obtained by solution combustion synthesis using dextrose as fuel

    SciTech Connect

    Subohi, Oroosa; Shastri, Lokesh; Kumar, G.S.; Malik, M.M.; Kurchania, Rajnish

    2014-01-01

    Graphical abstract: X-ray diffraction studies show that phase formation and crystallinity was reached only after calcinations at 800 °C. Dielectric constant versus temperature curve shows ferroelectric to paraelectric transition temperature (T{sub c}) to be 650 °C. Complex impedance curves show deviation from Debye behavior. The material shows a thin PE Loop with low remnant polarization due to high conductivity in the as prepared sample. - Highlights: • Bi{sub 4}Ti{sub 3}O{sub 12} is synthesized using solution combustion technique with dextrose as fuel. • Dextrose has high reducing capacity (+24) and generates more no. of moles of gases. • Impedance studies show that the sample follows Maxwell–Wagner relaxation behavior. • Shows lower remnant polarization due to higher c-axis ratio. - Abstract: Structural, dielectric and ferroelectric properties of bismuth titanate (Bi{sub 4}Ti{sub 3}O{sub 12}) obtained by solution combustion technique using dextrose as fuel is studied extensively in this paper. Dextrose is used as fuel as it has high reducing valancy and generates more number of moles of gases during the reaction. X-ray diffraction studies show that phase formation and crystallinity was reached only after calcinations at 800 °C. Dielectric constant versus temperature curve shows ferroelectric to paraelectric transition temperature (T{sub c}) to be 650 °C. The dielectric loss is very less (tan δ < 1) at lower temperatures but increases around T{sub c} due to structural changes in the sample. Complex impedance curves show deviation from Debye behavior. The material shows a thin PE Loop with low remnant polarization due to high conductivity in the as prepared sample.

  1. Acquired immunodeficiency syndrome: Ga-67 citrate imaging

    SciTech Connect

    Woolfenden, J.M.; Carrasquillo, J.A.; Larson, S.M.; Simmons, J.T.; Masur, H.; Smith, P.D.; Shelhamer, J.H.; Ognibene, F.P.

    1987-02-01

    All gallium-67 citrate scans obtained in patients with acquired immunodeficiency syndrome (AIDS) at the Clinical Center, National Institutes of Health (Bethesda, Md.) were retrospectively analyzed and correlated with the results of bronchoscopy, chest radiography, and endoscopy. There were 164 scans of 95 patients. Twenty scans were from patients with Pneumocystis carinii pneumonia; 19 were abnormal, for a sensitivity of 95%. Ga-67 uptake tended to be less in patients receiving therapy for P. carinii pneumonia. Chest radiographs were normal at least initially in three patients with abnormal scans and P. carinii pneumonia. Unusually prominent colonic activity was associated with infection in some patients. No lesions of Kaposi sarcoma showed tracer uptake. Gallium scanning is useful for detecting P. carinii pneumonia and other opportunistic infections in patients with AIDS, but it is not useful for localizing Kaposi sarcoma.

  2. Citrate substitutes for homocitrate in nitrogenase of a nifV mutant of Klebsiella pneumoniae

    SciTech Connect

    Liang, Jihong; Madden, M.; Shah, V.K.; Burris, R.H. )

    1990-09-18

    An organic acid extracted from purified dinitrogenase isolated from a nifV mutant of Klebsiella pneumoniae has been identified as citric acid. H{sub 2} evolution by the citrate-containing dinitrogenase is partially inhibited by CO, and by some substrates for nitrogenase. The response of maximum velocities to changes in pH for both the wild-type and the NifV{sup {minus}} dinitrogenase was compared. No substantial differences between the enzymes were observed, but there are minor differences. Both enzymes are stable in the pH range 4.8-10, but the enzyme activities dropped dramatically below pH 6.2.

  3. Self-healable and reversible liposome leakage by citrate-capped gold nanoparticles: probing the initial adsorption/desorption induced lipid phase transition

    NASA Astrophysics Data System (ADS)

    Wang, Feng; Liu, Juewen

    2015-09-01

    We herein report that the adsorption/desorption of citrate-capped gold nanoparticles (AuNPs) transiently causes leakage in fluid phase DOPC liposomes, while the liposomes do not leak with AuNPs capped with mercaptopropionic acid (MPA). Leakage also fails to occur for gel phase DPPC liposomes. Citrate-capped (but not MPA-capped) AuNPs raise the phase transition temperature of DPPC. We conclude that citrate-capped AuNPs interact with the PC liposomes very strongly, inducing a local fluid-to-gel lipid phase transition for DOPC. Leakage takes place during this transition, and the membrane integrity is resumed after the transition. Citrate-capped AuNPs allow stronger van der Waals forces than MPA-capped AuNPs with PC liposomes, since the latter are separated from the liposome surface by the ~0.3 nm MPA layer.We herein report that the adsorption/desorption of citrate-capped gold nanoparticles (AuNPs) transiently causes leakage in fluid phase DOPC liposomes, while the liposomes do not leak with AuNPs capped with mercaptopropionic acid (MPA). Leakage also fails to occur for gel phase DPPC liposomes. Citrate-capped (but not MPA-capped) AuNPs raise the phase transition temperature of DPPC. We conclude that citrate-capped AuNPs interact with the PC liposomes very strongly, inducing a local fluid-to-gel lipid phase transition for DOPC. Leakage takes place during this transition, and the membrane integrity is resumed after the transition. Citrate-capped AuNPs allow stronger van der Waals forces than MPA-capped AuNPs with PC liposomes, since the latter are separated from the liposome surface by the ~0.3 nm MPA layer. Electronic supplementary information (ESI) available: Methods, TEM, UV-vis and DLS data. See DOI: 10.1039/c5nr04805b

  4. Intranasal microemulsion of sildenafil citrate: in vitro evaluation and in vivo pharmacokinetic study in rabbits.

    PubMed

    Elshafeey, Ahmed H; Bendas, Ehab R; Mohamed, Osama H

    2009-01-01

    The purpose of the present study was to prepare intranasal delivery system of sildenafil citrate and estimate its relative bioavailability after nasal administration in rabbits to attain rapid onset of action with good efficacy at lower doses. Sildenafil citrate saturated solubility was determined in different solvents, cosolvents, and microemulsion systems. For nasal application, sildenafil citrate was formulated in two different systems: the first was a cosolvent system (S3) of benzyl alcohol/ethanol/water/Transcutol/taurodeoxy cholate/Tween 20 (0.5:16.8:47.7:15.9:1:18.1% w/w). The second was a microemulsion system (ME6) containing Oleic acid: Labrasol/Transcutol/water (8.33:33.3:16.66:41.66% w/w). The prepared systems were characterized in relation to their clarity, particle size, viscosity, pH, and nasal ciliotoxicity. In vivo pharmacokinetic performance of the selected system ME6 (with no nasal ciliotoxicity) was evaluated in a group of six rabbits in a randomized crossover study and compared to the marketed oral tablets. The targeted solubility (>20 mg/ml) of sildenafil citrate was achieved with cosolvent systems S1, S3, and S5 and with microemulsion systems ME3-ME6. The saturated solubility of sildenafil citrate in cosolvent system S3 and microemulsion system ME6 were 22.98 +/- 1.26 and 23.79 +/- 1.16 mg/ml, respectively. Microemulsion formulation ME6 showed shorter t (max) (0.75 h) and higher AUC((0-infinity)) (1,412.42 ng h/ml) compared to the oral tablets which showed t (max) equals 1.25 h and AUC((0-infinity)) of 1,251.14 ng h/ml after administration to rabbits at dose level of 5 mg/kg. The relative bioavailability was 112.89%. In conclusion, the nasal absorption of sildenafil citrate microemulsion was found to be fast, indicating the potential of nasal delivery instead of the conventional oral administration of such drug.

  5. Effect of intrauterine dextrose on reproductive performance of lactating dairy cows diagnosed with purulent vaginal discharge under certified organic management.

    PubMed

    Maquivar, M G; Barragan, A A; Velez, J S; Bothe, H; Schuenemann, G M

    2015-06-01

    The objectives of the study were to assess responses to treatments (clinical cure and resumption of estrous cycles) of cows with purulent vaginal discharge (PVD) that received intrauterine infusion of a hypertonic solution of 50% dextrose (DEX) or untreated control (CON) cows and the subsequent pregnancy per artificial insemination (PAI) in cows with and without PVD. Cows (n=2,852) from 2 dairy herds were screened for PVD using the gloved hand technique at exam 1 [26±3 d in milk (DIM)]. Cows with vaginal discharge scores of 2 or 3 (0-3 scale) were stratified by parity and randomly allocated into 1 of 2 treatment groups: (1) intrauterine infusion (~200 mL) of 50% DEX solution (n=456), or (2) untreated control animals (CON, n=491). Fourteen days posttherapy (40±3 DIM), cows with PVD were re-examined at exam 2 (40±3 DIM) to assess the response to treatments. All cows were subjected to the same reproductive program, which consisted of estrus detection twice daily (using tail chalking and visual observation) for the first 5 artificial inseminations; then, open lactating cows were turned out with bulls. Cows displaying signs of standing estrus underwent AI and no reproductive hormones were used. Pregnancy diagnosis (PD) was performed via transrectal palpation at 40±3 d post-AI. The risk of culling within 14 d posttherapy was not different among treatment groups. Cows with PVD had greater cervical diameter at exam 1 and decreased PAI compared with cows without PVD. Treatment with DEX increased the proportion of cows with clear vaginal discharge (clinical cure) and cyclicity 14 d posttherapy compared with CON cows. Pregnancy per AI for DEX (29.2±2%) cows was significantly greater than that for CON (22.5±2%) cows. Cows without PVD had a greater proportion of cycling cows (65.6%) and PAI (37%) with reduced pregnancy losses (5.7%) compared with DEX or CON cows. The use of intrauterine DEX alone improved reproductive performance of cows with PVD.

  6. Effectiveness and Safety Assessment of Citrate Anticoagulation During Albumin Dialysis in Comparison to Other Methods of Anticoagulation.

    PubMed

    Dyla, Agnieszka; Mielnicki, Wojciech; Bartczak, Joanna; Zawada, Tomasz; Garba, Piotr

    2017-03-23

    Liver failure is a serious and often deadly disease often requiring MARS (Molecular Adsorbent Recirculating System) therapy. Choosing the safe and effective method of anticoagulation during artificial liver support systems seems to be very difficult and extremely important. The aim of this study was to assess effectiveness and safety of regional anticoagulation with citrate in liver failure patients during MARS. We used a single center observational study. We analyzed 158 MARS sessions performed in 65 patients: 105 (66.5%) sessions in 41 patients with heparin anticoagulation, 40 (25.3%) sessions in 19 patients with citrate, and 13 (8%) sessions in only five patients without anticoagulation, that were excluded from part of the analysis. To determine the effectiveness of regional anticoagulation with citrate, probability of filter survival and changes in laboratory parameters were analyzed according to the applied method of anticoagulation. The safety of citrate was determined by Ca/Ca(2+) ratio, acid-base balance, bleeding complications, and the need for blood product transfusions. The probability of filter survival in the citrate group was 94% and in the heparin group 82% (P = 0.204). There was no relationship between the method of anticoagulation and effectiveness of MARS therapy in lowering the levels of the analyzed parameters. Only one patient had a Ca/Ca(2+) ratio higher than he safety margin. There were no statistically significant changes in pH and lactate level irrespective of anticoagulation; bicarbonate dropped significantly only in the heparin group (P = 0.03). The frequency of bleeding complications and the need for transfusions did not differ significantly between groups. Regional anticoagulation with citrate can be an effective and safe method of anticoagulation during MARS therapy, but requires attentive monitoring and further studies in liver failure patients.

  7. Low Temperature Induced Changes in Citrate Metabolism in Ponkan (Citrus reticulata Blanco cv. Ponkan) Fruit during Maturation

    PubMed Central

    Lin, Qiong; Qian, Jing; Zhao, Chenning; Wang, Dengliang; Liu, Chunrong; Wang, Zhidong; Sun, Chongde; Chen, Kunsong

    2016-01-01

    Citrate is the most important organic acid in citrus fruit, and its concentration in fruit cells is regulated mainly by the balance between synthesis and degradation. Ponkan (Citrus reticulate Blanco cv. Ponkan) is one of the major citrus cultivars grew in China, and the fruit are picked before fully mature to avoid bad weather. Greenhouse production is widely used to prolong the maturation period and improve the quality of Ponkan fruit by maintaining adequate temperature and providing protection from adverse weather. In this research, Ponkan fruit cultivated in either a greenhouse or open field were used to investigate differences in the expression of genes related to citrate metabolism during maturation in the two environments. The citrate contents were higher in open field fruit, and were mainly correlated with expressions of CitPEPCs, CitCSs, CitAco3 and CitGAD4, which were significantly increased. In addition, the impacts of low temperature (LT) and water stress (WS) on citrate metabolism in Ponkan were investigated during fruit maturation. The citrate contents in LT fruit were significantly increased, by between 1.4–1.9 fold, compared to the control; it showed no significant difference in fruit with water stress treatment compared to the control fruit. Furthermore, the expressions of CitPEPCs, CitCSs, CitAco3 and CitGAD4 were significantly increased in response to LT treatment, but showed no significant difference in WS compared to the control fruit. Thus, it can be concluded that low temperature may be the main factor influencing citrate metabolism during maturation in Ponkan fruit. PMID:27249065

  8. The impact of particle size on the adsorption of citrate to hematite.

    PubMed

    Noerpel, Matthew R; Lenhart, John J

    2015-12-15

    We investigated the adsorption of citric acid on the surface of two different sized hematite nanoparticles using batch adsorption experiments, Fourier-transform infrared spectroscopy, surface complexation modeling and computational molecular modeling. Citrate adsorption reached a maximum between pH approximately 2.5 and 5.5 and declined as the pH was increased or decreased from that range. At high surface loading conditions, the dominant adsorbed citrate structure was outer-sphere in nature with a protonation state that varied with pH. At low pH, there was also evidence of an inner-sphere complex consistent with a binuclear, bidentate structure where the hydroxyl group was deprotonated and played an active role in the adsorption. An inner-sphere complex was also detected at low citrate surface loading conditions. Surface-area normalized surface coverages were similar for both sizes of hematite, however, the inner sphere complex appeared to be slightly more prevalent on the smaller hematite. Based on these structures, a triple layer surface complexation model comprised of two outer-sphere complexes and one inner-sphere complex was used to describe the adsorption data for both hematite sizes across a range of solution conditions with a single set of surface area dependent equilibrium constants.

  9. Ionized hypomagnesemia in patients undergoing orthotopic liver transplantation: a complication of citrate intoxication.

    PubMed

    Scott, V L; De Wolf, A M; Kang, Y; Altura, B T; Virji, M A; Cook, D R; Altura, B M

    1996-09-01

    Using a new ion-selective electrode, plasma concentration of ionized magnesium was measured in nine adult patients undergoing orthotopic liver transplantation. Baseline plasma ionized magnesium (IMg2+) concentration (0.49 +/- 0.07 mmol/L) was slightly below normal values (0.55-0.66 mmol/L, 95% CI): Six patients had ionized hypomagnesemia and two of these had total hypomagnesemia. Ionized IMg2+ concentration progressively decreased during the dissection (0.45 +/- 0.07 mmol/L, p < 0.05) and anhepatic stage (0.38 +/- 0.07 mmol/L, p < 0.05) and returned toward baseline values by 2 hours after graft reperfusion. Plasma ionized calcium levels and acid-base status were maintained within normal limits during surgery. Serum citrate concentration increased during the dissection (0.58 +/- 0.60 mmol/L) and anhepatic stages (1.18 +/- 0.78 mmol/L), the result of transfusion of citrate-rich blood products in the absence of adequate hepatic function, and gradually returned toward baseline values after graft reperfusion. IMg2+ concentration inversely correlated with the plasma citrate concentration (r2 = 0.54). The results of this study demonstrate that ionized hypomagnesemia invariably occurs during liver transplantation and suggest that this derangement may be a clinical concern, because magnesium is an important cofactor for the maintenance of cardiovascular homeostasis. The data further suggest the clinical importance of supplementation with magnesium based on the monitoring of plasma IMg2+ concentration.

  10. Bacterial citrate synthase expression and soil aluminum tolerance in transgenic alfalfa.

    PubMed

    Barone, Pierluigi; Rosellini, Daniele; Lafayette, Peter; Bouton, Joseph; Veronesi, Fabio; Parrott, Wayne

    2008-05-01

    Alfalfa is very sensitive to soil acidity and its yield and stand duration are compromised due to inhibited root growth and reduced nitrogen fixation caused by Al toxicity. Soil improvement by liming is expensive and only partially effective, and conventional plant breeding for Al tolerance has had limited success. Because tobacco and papaya plants overexpressing Pseudomonas aeruginosa citrate synthase (CS) have been reported to exhibit enhanced tolerance to Al, alfalfa was engineered by introducing the CS gene controlled by the Arabidopsis Act2 constitutive promoter or the tobacco RB7 root-specific promoter. Fifteen transgenic plants were assayed for exclusion of Al from the root tip, for internal citrate content, for growth in in vitro assays, or for shoot and root growth in either hydroponics or in soil assays. Overall, only the soil assays yielded consistent results. Based on the soil assays, two transgenic events were identified that were more aluminum-tolerant than the non-transgenic control, confirming that citrate synthase overexpression can be a useful tool to help achieve aluminum tolerance.

  11. Simultaneous growth on citrate reduces the effects of iron limitation during toluene degradation in Pseudomonas.

    PubMed

    Dinkla, I J T; Janssen, D B

    2003-01-01

    Rhizoremediation has been suggested as an attractive bioremediation strategy for the effective breakdown of pollutants in soil. The presence of plant root exudates such as organic acids, sugars, and amino acids that may serve as carbon sources or biosynthetic building blocks and the limited bioavailability of iron may influence the degradation of pollutants in the rhizosphere. To test the effect of such compounds on hydrocarbon degradation, trace concentrations of yeast extract or mixtures of organic acids and amino acids were added to continuous cultures of Pseudomonas putida mt2 and P. putida WCS358 (TOL) growing on toluene. By addition of these compounds increased growth yields and higher specific growth rates on toluene were obtained. The effects of iron limitation on the substrate utilization pattern of both strains were tested by growing the strains on a mixture of toluene and the readily degradable carbon source citrate while the iron concentration was varied. Simultaneous use of both substrates under carbon-limited as well as iron-limited conditions was observed. Growth yields were less reduced and iron requirement was lower during iron-limited growth in the toluene + citrate grown cultures compared to cultures in which toluene was used as the sole carbon source. The kinetic properties of the cells for toluene degradation were less hampered by the lack of iron when citrate was used as an additional carbon source. The results indicate that the availability of low concentrations of natural organic compounds, such as produced in the rhizosphere, may positively influence the degradative performance of hydrocarbon-degrading bacteria.

  12. Citrate-Linked Keto- and Aldo-Hexose Monosaccharide Cellulose Conjugates Demonstrate Selective Human Neutrophil Elastase-Lowering Activity in Cotton Dressings

    PubMed Central

    Edwards, Judson V.; Caston-Pierre, Sonya

    2013-01-01

    Sequestration of harmful proteases as human neutrophil elastase (HNE) from the chronic wound environment is an important goal of wound dressing design and function. Monosaccharides attached to cellulose conjugates as ester-appended aldohexoses and ketohexoses were prepared on cotton gauze as monosccharide-citrate-cellulose-esters for HNE sequestration. The monosaccharide-cellulose analogs demonstrated selective binding when the derivatized cotton dressings were measured for sequestration of HNE. Each monosaccharide-cellulose conjugate was prepared as a cellulose citrate-linked monosaccharide ester on the cotton wound dressing, and assayed under wound exudate-mimicked conditions for elastase sequestration activity. A series of three aldohexose and four ketohexose ester cellulose conjugates were prepared on cotton gauze through citric acid-cellulose cross linking esterification. The monosaccharide portion of the conjugate was characterized by hydrolysis of the citrate-monosaccharide ester bond, and subsequent analysis of the free monosaccharide with high performance anion exchange chromatography. The ketohexose and aldohexose conjugate levels on cotton were quantified on cotton using chromatography and found to be present in milligram/gram amounts. The citrate-cellulose ester bonds were characterized with FTIR. Ketohexose-citrate-cellulose conjugates sequestered more elastase activity than aldohexose-citrate-cellulose conjugates. The monosaccharide cellulose conjugate families each gave distinctive profiles in elastase-lowering effects. Possible mechanisms of elastase binding to the monosaccharide-cellulose conjugates are discussed. PMID:24955952

  13. Properties of peroxisomal and mitochondrial citrate synthase from Agave americana.

    PubMed

    Segovia, J L; Zafra, M F; Alejandre, M J; García-Peregrín, E

    1982-09-01

    Adenine nucleotides were tested as effectors of peroxisomal and mitochondrial citrate synthase from Agave americana leaves in the presence of different concentrations of acetyl-CoA and oxalacetate substrates. ATP inhibited both enzyme activities but with a different inhibition profile. 1.0-7.5 mM ADP did not inhibit the peroxisomal citrate synthase in the presence of high substrate concentrations, while the mitochondrial enzyme was strongly inhibited by 1.0 mM ADP in the same conditions. Likewise, a different pattern was obtained with AMP on both peroxisomal and mitochondrial activities. The rate of citrate formation as function of acetyl-CoA and oxalacetate concentration was also studied in both fractions. Maximal velocity was highest in the peroxisomal fraction, whether acetyl-CoA or oxalacetate were the variable substrates. These differences indicate that peroxisomal and mitochondrial citrate synthases seem to be two different isoenzymes.

  14. Injectable citrate-modified Portland cement for use in vertebroplasty

    PubMed Central

    Wynn-Jones, Gareth; Shelton, Richard M; Hofmann, Michael P

    2014-01-01

    The injectability of Portland cement (PC) with several citrate additives was investigated for use in clinical applications such as vertebroplasty (stabilization of a fractured vertebra with bone cement) using a syringe. A 2-wt % addition of sodium or potassium citrate with PC significantly improved cement injectability, decreased cement setting times from over 2 h to below 25 min, while increasing the compressive strength to a maximum of 125 MPa. Zeta-potential measurements indicated that the citrate anion was binding to one or more of the positively charged species causing charged repulsion between cement particles which dispersed aggregates and caused the liquefying effect of the anion. Analysis of the hydrating phases of PC indicated that the early strength producing PC phase (ettringite) developed within the first 2 h of setting following addition of the citrate anion, while this did not occur in the control cement (PC only). Within 24 h ettringite developed in PC as well as calcium–silicate–hydrate (C–S–H), the major setting phase of PC, whereas cements containing citrate did not develop this phase. The evidence suggested that in the presence of citrate the cements limited water supply appeared to be utilized for ettringite formation, producing the early strength of the citrate cements. The present study has demonstrated that it is possible to modify PC with citrate to both improve the injectability and crucially reduce the setting times of PC while improving the strength of the cement. © 2014 The Authors Journal of Biomedical Materials Research Part B: Applied Biomaterials Published by Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 102B: 1799–1808, 2014. PMID:24711245

  15. Citrate-Based Biomaterials and Their Applications in Regenerative Engineering

    NASA Astrophysics Data System (ADS)

    Tran, Richard T.; Yang, Jian; Ameer, Guillermo A.

    2015-07-01

    Advances in biomaterials science and engineering are crucial to translating regenerative engineering, an emerging field that aims to recreate complex tissues, into clinical practice. In this regard, citrate-based biomaterials have become an important tool owing to their versatile material and biological characteristics including unique antioxidant, antimicrobial, adhesive, and fluorescent properties. This review discusses fundamental design considerations, strategies to incorporate unique functionality, and examples of how citrate-based biomaterials can be an enabling technology for regenerative engineering.

  16. Citrate-Based Biomaterials and Their Applications in Regenerative Engineering

    PubMed Central

    Tran, Richard T.; Yang, Jian; Ameer, Guillermo A.

    2015-01-01

    Advances in biomaterials science and engineering are crucial to translating regenerative engineering, an emerging field that aims to recreate complex tissues, into clinical practice. In this regard, citrate-based biomaterials have become an important tool owing to their versatile material and biological characteristics including unique antioxidant, antimicrobial, adhesive, and fluorescent properties. This review discusses fundamental design considerations, strategies to incorporate unique functionality, and examples of how citrate-based biomaterials can be an enabling technology for regenerative engineering. PMID:27004046

  17. Mutational analysis of the CitA citrate transporter from Salmonella typhimurium: altered substrate specificity.

    PubMed

    Shimamoto, T; Negishi, K; Tsuda, M; Tsuchiya, T

    1996-09-13

    The CitA citrate transporter in Salmonella typhimurium is encoded by the citA gene and consists of 434 amino acid residues that probably include 12 membrane-spanning segments [Shimamoto. T., et al. (1991) J. Biochem. 110, 22-28]. CitA mutants with altered substrate specificities were isolated by in vitro mutagenesis using nitrous acid. The mutants could grow on isocitrate as a sole carbon source which normally cannot be transported well by the CitA transporter of S. typhimurium. The mutation sites in the citA gene of the nine mutants were determined to involve single residues at seven sites (one mutation per mutant). The original amino acid residues at these sites (Arg-19, Ala-38, Glu-51, Gly-132, Ala-169, Pro-262 and Leu-271) were identified to be responsible for the altered substrate specificity. All these amino acid residues were conserved in four other homologous citrate transporters from Escherichia coli, Citrobacter amalonaticus and Klebsiella pneumoniae and are suggested to be involved in substrate recognition by the CitA transporter.

  18. The correlations among serum tumor necrosis factor-alpha (TNF-alpha), interferon-gamma (IFN-gamma) and sialic acids with peripheral lymphocytes in bovine tropical theileriosis.

    PubMed

    Razavi, Seyed Mostafa; Nazifi, Saeed; Emadi, Mahboobeh; Rakhshandehroo, Ehsan

    2010-10-01

    The infection with protozoan parasite Theileria annulata induces changes triggering the activation and/or proliferation of the host lymphocytes. In order to find out the possible correlations among peripheral circulatory lymphocytes, cytokine activities and the level of sialic acids, 50 dairy Holstein cattle, naturally infected with T. annulata, were divided into 4 subgroups according to their parasitemia rates (<1%, 1-3%, 3-5% and >5%). Also, ten non-infected cattle were sampled as control group. Blood samples were taken from jugular vein into acid citrate dextrose-containing tubes for measuring hematological parameters and B and T (CD(4) and CD(8)) cell populations and without anticoagulant for TNF-alpha, IFN-gamma and sialic acid concentrations. Remarkable decreases observed in red blood cells (RBCs), white blood cells (WBCs) and packed cell volume (PCV) in infected cattle compared to healthy ones (P < 0.05). Also, with increase in parasitemia rate, total lymphocytes and monocytes alleviated in the diseased groups. By contrast, total neutrohpils and the concentrations of TNF-alpha, IFN-gamma and total sialic acids were significantly elevated (P < 0.05) in infected animals. Accordingly, the circulatory populations of CD(4) and CD(8) T cells and B cells showed a substantial decrease, while a significant increase was observed in T (CD(4) and CD(8)) cells in cattle infected with <1% parasitemia rates. Decreased circulatory T cell population shows the ineffective responses of T cells to the stimulatory cytokines such as IFN-gamma or TNF-alpha. On the other hand, the elevation of cytokines (particularly IFN-gamma) and sialic acids have presumably an inhibitory role on circulatory B cell population in infected cattle. In addition, a high level of sialic acid concentration indicates the probable role of sialic acid to regulate the parasite-host cell adhesion during sporozoites invasion.

  19. Compatibility and stability of potassium chloride and magnesium sulfate in 0.9% sodium chloride injection and 5% dextrose injeciton solutions.

    PubMed

    Quay, I; Tan, E

    2001-01-01

    The compatibility and stability of 80 mmol/L potassium chloride and 16 mmol/L magnesium sulfate in 0.9% sodium chloride injection and in 5% dextrose injection solutions at 22 deg C have been studied by means of a Beckman Clinical Chemistry Analyzer Synchron CX5 Delta. The infusions were stable for 24 hours at 22 deg C. The results from both diluents showed an average of +/-5% fluctuations in concentration. None of the samples appeared to form visible precipitation or to change in color or clarity.

  20. Scaling of Structural and Rheological Responde of L3 Sponge Phases in the "Sweetened" Cetylpyridinium/Hexanol/Dextrose/Brine System

    SciTech Connect

    Porcar, L.; Hamilton, William A; Butler, Paul D; Warr, G. G.

    2003-01-01

    We report a study of the shear response of sponge phases in cetylpyridinium chloride (CPCl)/hexanol/brine/dextrose systems by parallel measurements of rheology and structure by small angle neutron scattering (SANS). Our measurements show that this dextrose added to the extensively studied CPCl/hexanol/brine system is taken up exclusively by the brine solvent, resulting in an equivalent CPCl/hexanol membrane structure and phase behavior for this modified system. Adding dextrose to the brine in these systems to volume fractions up to 0.4 allows us to increase the solvent viscosity by more than an order of magnitude. This lowers the cooperative membrane diffusion coefficient in this system as measured by dynamic light scattering by the same factor, resulting in a corresponding slowing of the Helfrich fluctuation dominated membrane dynamics. Our results show clear and consistent evidence of shear-induced sponge to lamellar phase transformations in these systems. Further, both the rheological and microstructural responses of these systems follow universal master curves when plotted against a rescaled applied shear {sub {gamma}}{eta}{sub s}/{phi}{sup 3}, where {phi} is the membrane volume fraction and {eta}{sub s} is the viscosity of the brine/dextrose solvent. This well-defined shear response is characterized by three distinct regimes. At low shear rates the sponge phases exhibit Newtonian flow behavior and no structural change is observed. For intermediate shear rates, the systems shear thin and SANS measurements show that the sponge phases are progressively transformed into lamellar phases with the CPCl/hexanol membrane normals aligned parallel to the velocity gradient. This continuous process and the absence of a stress plateau in the rheological measurements both rule out the existence of a biphasic state in this region and thus of a first-order transition between sponge and lamellar phases as is observed in equilibrium phase diagrams. At higher shear rates, the

  1. Effect of citrate on Aspergillus niger phytase adsorption and catalytic activity in soil

    NASA Astrophysics Data System (ADS)

    Mezeli, Malika; Menezes-Blackburn, Daniel; Zhang, Hao; Giles, Courtney; George, Timothy; Shand, Charlie; Lumsdon, David; Cooper, Patricia; Wendler, Renate; Brown, Lawrie; Stutter, Marc; Blackwell, Martin; Darch, Tegan; Wearing, Catherine; Haygarth, Philip

    2015-04-01

    Current developments in cropping systems that promote mobilisation of phytate in agricultural soils, by exploiting plant-root exudation of phytase and organic acids, offer potential for developments in sustainable phosphorus use. However, phytase adsorption to soil particles and phytate complexion has been shown to inhibit phytate dephosphorylation, thereby inhibiting plant P uptake, increasing the risk of this pool contributing to diffuse pollution and reducing the potential benefits of biotechnologies and management strategies aimed to utilise this abundant reserve of 'legacy' phosphorus. Citrate has been seen to increase phytase catalytic efficiency towards complexed forms of phytate, but the mechanisms by which citrate promotes phytase remains poorly understood. In this study, we evaluated phytase (from Aspergillus niger) inactivation, and change in catalytic properties upon addition to soil and the effect citrate had on adsorption of phytase and hydrolysis towards free, precipitated and adsorbed phytate. A Langmuir model was fitted to phytase adsorption isotherms showing a maximum adsorption of 0.23 nKat g-1 (19 mg protein g-1) and affinity constant of 435 nKat gˉ1 (8.5 mg protein g-1 ), demonstrating that phytase from A.niger showed a relatively low affinity for our test soil (Tayport). Phytases were partially inhibited upon adsorption and the specific activity was of 40.44 nKat mgˉ1 protein for the free enzyme and 25.35 nKat mgˉ1 protein when immobilised. The kinetics of adsorption detailed that most of the adsorption occurred within the first 20 min upon addition to soil. Citrate had no effect on the rate or total amount of phytase adsorption or loss of activity, within the studied citrate concentrations (0-4mM). Free phytases in soil solution and phytase immobilised on soil particles showed optimum activity (>80%) at pH 4.5-5.5. Immobilised phytase showed greater loss of activity at pH levels over 5.5 and lower activities at the secondary peak at pH 2

  2. Alkali absorption and citrate excretion in calcium nephrolithiasis

    NASA Technical Reports Server (NTRS)

    Sakhaee, K.; Williams, R. H.; Oh, M. S.; Padalino, P.; Adams-Huet, B.; Whitson, P.; Pak, C. Y.

    1993-01-01

    The role of net gastrointestinal (GI) alkali absorption in the development of hypocitraturia was investigated. The net GI absorption of alkali was estimated from the difference between simple urinary cations (Ca, Mg, Na, and K) and anions (Cl and P). In 131 normal subjects, the 24 h urinary citrate was positively correlated with the net GI absorption of alkali (r = 0.49, p < 0.001). In 11 patients with distal renal tubular acidosis (RTA), urinary citrate excretion was subnormal relative to net GI alkali absorption, with data from most patients residing outside the 95% confidence ellipse described for normal subjects. However, the normal relationship between urinary citrate and net absorbed alkali was maintained in 11 patients with chronic diarrheal syndrome (CDS) and in 124 stone-forming patients devoid of RTA or CDS, half of whom had "idiopathic" hypocitraturia. The 18 stone-forming patients without RTA or CDS received potassium citrate (30-60 mEq/day). Both urinary citrate and net GI alkali absorption increased, yielding a significantly positive correlation (r = 0.62, p < 0.0001), with the slope indistinguishable from that of normal subjects. Thus, urinary citrate was normally dependent on the net GI absorption of alkali. This dependence was less marked in RTA, confirming the renal origin of hypocitraturia. However, the normal dependence was maintained in CDS and in idiopathic hypocitraturia, suggesting that reduced citrate excretion was largely dietary in origin as a result of low net alkali absorption (from a probable relative deficiency of vegetables and fruits or a relative excess of animal proteins).

  3. Absorption and Bioavailability of Nano-Size Reduced Calcium Citrate Fortified Milk Powder in Ovariectomized and Ovariectomized-Osteoporosis Rats.

    PubMed

    Erfanian, Arezoo; Mirhosseini, Hamed; Rasti, Babak; Hair-Bejo, Mohd; Bin Mustafa, Shuhaimi; Abd Manap, Mohd Yazid

    2015-06-24

    The aim of this study was to evaluate the effects of fortification and nano-size reduction on calcium absorption and bioavailability of milk powder formula in sham, ovariectomized, and ovariectomized-osteoporosis rats as a menopause and menopause-osteoporosis model. Skim milk powder and skim milk powder fortified with calcium citrate and the suitable doses of inulin, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), and vitamins D3, K1, and B6 were formulated based on the North American and Western European recommended dietary allowances. Optimization on cycle and pressure of high-pressure homogenizer was done to produce nano-fortified milk powder. In vivo study demonstrated that fortification and calcium citrate nano-fortified milk powder increased absorption and bioavailability of calcium, as well as bone stiffness and bone strength in sham, ovariectomized, and ovariectomized-osteoporosis rats. This study successfully developed an effective fortified milk powder for food application.

  4. Treatment Efficacy and Safety During Plasma Exchange With Citrate Anticoagulation: A Randomized Study of 4 Versus 15% Citrate.

    PubMed

    Antonic, Manja; Gubensek, Jakob; Buturovic-Ponikvar, Jadranka; Ponikvar, Rafael

    2016-04-01

    In plasma exchange (PE), contrary to dialysis, there is no ultrafiltration, and the volume of anticoagulant contributes to volume overload of the patient and might also reduce PE efficiency through dilution. To reduce the volume of citrate, we compared 4 and 15% citrate anticoagulation protocols in PE in a randomized study, aiming to evaluate PE efficacy, anticoagulation efficiency, and overall safety. In addition to standard biochemical analyses during PE treatments, the elimination rate (ER) of immunoglobulins was calculated to evaluate PE efficacy. Anticoagulation was evaluated by postfilter ionized calcium, visual evaluation of the extracorporeal system, and change in the sieving coefficient (SC) during PE. Accumulation of citrate was determined by calculating the total-to-ionized calcium ratio and measuring the citrate concentration after PE. One hundred forty procedures (70 in each group) were performed in 37 patients. The mean citrate infusion rate was 197 ± 10 mL/h in the 4% and 59 ± 5.5 mL/h in the 15% groups, respectively; the total volume of infused citrate was 502 ± 77 mL versus 164 ± 52 mL (P < 0.001). ER for immunoglobulin G (0.57 ± 0.06 vs. 0.55 ± 0.1, P = 0.18), M, and A were comparable. Ionized calcium was stable during the procedures, and there were no significant side effects. Although postfilter ionized calcium was on the upper limit of the target range (0.41 ± 0.16 vs. 0.37 ± 0.14 mmol/L, P = 0.38), the visual assessment score was excellent, and even a rise in SC was observed during the procedures in both groups. The total-to-ionized calcium ratio was increased in 20 versus 22% of procedures, and citrate concentrations after PE were also similar (1306 ± 441 vs. 1263 ± 405 μmol/L). To conclude, we were unable to show superior PE efficacy in the 15% citrate group, but we significantly reduced the infused volume, which is important in patients with fluid overload. Both

  5. Nanoscale observations of the effect of citrate on calcium oxalate precipitation on calcite surfaces.

    NASA Astrophysics Data System (ADS)

    Burgos-Cara, Alejandro; Ruiz-Agudo, Encarnacion; Putnis, Christine V.

    2016-04-01

    Calcium oxalate (CaC2O4ṡxH2O) minerals are naturally occurring minerals found in fossils, plants, kidney stones and is a by-product in some processes such as paper, food and beverage production [1,2]. In particular, calcium oxalate monohydrate phase (COM) also known as whewellite (CaC2O4ṡH2O), is the most frequently reported mineral phase found in urinary and kidney stones together with phosphates. Organic additives are well known to play a key role in the formation of minerals in both biotic and abiotic systems, either facilitating their precipitation or hindering it. In this regard, recent studies have provided direct evidence demonstrating that citrate species could enhance dissolution of COM and inhibit their precipitation. [3,4] The present work aims at evauate the influence of pH, citrate and oxalic acid concentrations in calcium oxalate precipitation on calcite surfaces (Island Spar, Chihuahua, Mexico) through in-situ nanoscale observation using in situ atomic force microscopy (AFM, Multimode, Bruker) in flow-through experiments. Changes in calcium oxalate morphologies and precipitated phases were observed, as well as the inhibitory effect of citrate on calcium oxalate precipitation, which also lead to stabilization an the amorphous calcium oxalate phase. [1] K.D. Demadis, M. Öner, Inhibitory effects of "green"additives on the crystal growth of sparingly soluble salts, in: J.T. Pearlman (Ed.), Green Chemistry Research Trends, Nova Science Publishers Inc., New York, 2009, pp. 265-287. [2] M. Masár, M. Zuborová, D. Kaniansky, B. Stanislawski, Determination of oxalate in beer by zone electrophoresis on a chip with conductivity detection, J. Sep. Sci. 26 (2003) 647-652. [3] Chutipongtanate S, Chaiyarit S, Thongboonkerd V. Citrate, not phosphate, can dissolve calcium oxalate monohydrate crystals and detach these crystals from renal tubular cells. Eur J Pharmacol 2012;689:219-25. [4] Weaver ML, Qiu SR, Hoyer JR, Casey WH, Nancollas GH, De Yoreo JJ

  6. Enhancing the versatility of alternate current biosusceptometry (ACB) through the synthesis of a dextrose-modified tracer and a magnetic muco-adhesive cellulose gel.

    PubMed

    Martins, Murillo L; Calabresi, Marcos F; Quini, Caio; Matos, Juliana F; Miranda, José R A; Saeki, Margarida J; Bordallo, Heloisa N

    2015-03-01

    Alternate Current Biosusceptometry (ACB) is a promising bio-magnetic method, radiation free and easily performed used for gastric emptying exams. Due to development on its sensitivity level, interesting nature, noninvasiveness and low cost it has attracted a lot of attention. In this work, magnetic nanoparticles of Mn-Zn ferrite as well as dextrose-modified nanoparticles were synthesized to be used as possible tracers in ACB gastric emptying exams. In addition, a magnetic muco-adhesive gel was obtained by modifying the ferrite nanoparticles with cellulose. Based on in-vivo tests in rats, we show that the pure ferrite nanoparticles, whose isoelectric point was found to be at pH=3.2, present a great sensitivity to pH variations along the gastrointestinal tract, while the reduction of the isoelectric point by the dextrose modification leads to suitable nanoparticles for rapid gastric emptying examinations. On the other hand, the in-vivo tests show that the muco-adhesive cellulose gel presents substantial stomach adhesion and is a potential drug delivery system easily traceable by the ACB system.

  7. 21 CFR 172.832 - Monoglyceride citrate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... HUMAN CONSUMPTION (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION... monooleate and its citric acid monoester manufactured by the reaction of glyceryl monooleate with citric acid... percent-17 percent. (b) It is used, or intended for use, in antioxidant formulations for addition to...

  8. Glycerol citrate polyesters produced through microwave heating

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The influence of various heating methods without catalysis to prepare copolyesters from citric acid:glycerol blends were studied. In the presence of short term microwave treatments, i.e., 60 sec at 1200 W, blends of glycerol and citric acid invariably formed solid amorphous copolyesters. Fourier tra...

  9. pH-responsive delivery of doxorubicin from citrate-apatite nanocrystals with tailored carbonate content.

    PubMed

    Rodríguez-Ruiz, Isaac; Delgado-López, José Manuel; Durán-Olivencia, Miguel A; Iafisco, Michele; Tampieri, Anna; Colangelo, Donato; Prat, Maria; Gómez-Morales, Jaime

    2013-07-02

    In this work, the efficiency of bioinspired citrate-functionalized nanocrystalline apatites as nanocarriers for delivery of doxorubicin (DOXO) has been assessed. The nanoparticles were synthesized by thermal decomplexing of metastable calcium/citrate/phosphate solutions both in the absence (Ap) and in the presence (cAp) of carbonate ions. The presence of citrate and carbonate ions in the solution allowed us to tailor the size, shape, carbonate content, and surface chemistry of the nanoparticles. The drug-loading efficiency of the two types of apatite was evaluated by means of the adsorption isotherms, which were found to fit a Langmuir-Freundlich behavior. A model describing the interaction between apatite surface and DOXO is proposed from adsorption isotherms and ζ-potential measurements. DOXO is adsorbed as a dimer by means of a positively charged amino group that electrostatically interacts with negatively charged surface groups of nanoparticles. The drug-release profiles were explored at pHs 7.4 and 5.0, mimicking the physiological pH in the blood circulation and the more acidic pH in the endosome-lysosome intracellular compartment, respectively. After 7 days at pH 7.4, cAp-DOXO released around 42% less drug than Ap-DOXO. However, at acidic pH, both nanoassemblies released similar amounts of DOXO. In vitro assays analyzed by confocal microscopy showed that both drug-loaded apatites were internalized within GTL-16 human carcinoma cells and could release DOXO, which accumulated in the nucleus in short times and exerted cytotoxic activity with the same efficiency. cAp are thus expected to be a more promising nanocarrier for experiments in vivo, in situations where intravenous injection of nanoparticles are required to reach the targeted tumor, after circulating in the bloodstream.

  10. Colloid mobilization in the field using citrate to remediate chromium.

    PubMed

    Johnson, C R; Hellerich, L A; Nikolaidis, N P; Gschwend, P M

    2001-01-01

    We investigated the feasibility of cleaning aquifer sediments, long contaminated with chromium (Cr) from a metal plating facility, by detaching colloid-sized sorbents from the immobile aquifer solids and then pumping those colloids to the surface for treatment. In laboratory experiments using aquifer solids from the site, several solutions (water at various pHs, phosphate, oxalate, ascorbate, citrate) were examined for their ability to disperse colloids and Cr. Based on these tests, a 5 mM citrate solution at pH 7 was selected. Subsequently, such a citrate solution was used in the field in two single-well injection-withdrawal experiments. Large quantities of colloids were released immediately after injection. The colloidal particles mobilized by citrate in the field had more than 20 times higher Cr concentrations than did the average aquifer sediments, implying success in mobilizing Cr-associated phases. Further, laboratory and field tests showed that anion exchange of citrate for chromate caused some additional release of Cr from these aquifer solids.

  11. Development and validation of an UPLC method for rapid determination of ibuprofen and diphenhydramine citrate in the presence of impurities in combined dosage form.

    PubMed

    Rao, Dantu Durga; Sait, Shakil S; Mukkanti, K

    2011-04-01

    A novel, stability-indicating gradient reverse-phase ultra-performance liquid chromatographic method was developed for the simultaneous determination of ibuprofen and diphenhydramine citrate in the presence of degradation products and process related impurities in combined dosage form. The method was developed using C18 column with mobile phase containing a gradient mixture of solvent A and B. The eluted compounds were monitored at 220 nm. Ibuprofen and diphenhydramine citrate were subjected to the stress conditions of oxidative, acid, base, hydrolytic, thermal, and photolytic degradation. Major unknown impurity formed under oxidative degradation was identified using LC-MS-MS study. The developed method was validated as per ICH guidelines with respect to specificity, linearity, limit of detection, limit of quantitation, accuracy, precision and robustness. The described method was linear over the range of 0.20-6.00 μg/mL (r>0.998) for Ibuprofen and 0.084-1.14 μg/mL for diphenhydramine citrate (r>0.998). The limit of detection results were ranged from 0.200-0.320 μg/mL for ibuprofen impurities and 0.084-0.099 μg/mL for diphenhydramine citrate impurities. The limit of quantitation results were ranged from 0.440 to 0.880 μg/mL for ibuprofen impurities and 0.258 to 0.372 μg/mL for diphenhydramine citrate impurities. The recovery of ibuprofen impurities were ranged from 98.1% to 100.5% and the recovery of diphenhydramine citrate impurities were ranged from 97.5% to 102.1%. This method is also suitable for the simultaneous assay determination of ibuprofen and diphenhydramine citrate in pharmaceutical dosage forms.

  12. Magnetic nanoparticles coated with cyclodextrins and citrate for irinotecan delivery.

    PubMed

    Monteiro, Ana P F; Caminhas, Larissa D; Ardisson, José D; Paniago, Roberto; Cortés, Maria E; Sinisterra, Rubén D

    2017-05-01

    In the present work, we study the role of different components in the formation of more stable iron oxide magnetic nanoparticles (MNPs): β-cyclodextrin (BCD), 2-hydroxypropyl-β-cyclodextrin (HP) and citrate anion. MNPs formulations were characterized by FTIR, particles size measurements, zeta potential based on dynamic light scattering principle technique, X-ray powder pattern diffraction, XPS spectroscopy, transmission electron microscopy and thermogravimetric analysis. The results showed that cyclodextrins and citrate plays a key role in order to obtain a lower size of coated MNPs and proved to be an efficient strategy to obtain a more stable colloidal dispersion, avoiding the nanoparticles oxidation, enhancing the irinotecan incorporation and release. Furthermore, citrate-coated BCD-MNPs showed the same cytotoxicity of the free IRI.

  13. Utility of Aspergillus niger citrate synthase promoter for heterologous expression.

    PubMed

    Dave, Kashyap; Punekar, Narayan S

    2011-09-10

    Citrate synthase is a central player in the acidogenic metabolism of Aspergillus niger. The 5' upstream sequence (0.9kb DNA) of citrate synthase gene (citA) from A. niger NCIM 565 was analyzed and its promoter function demonstrated through the heterologous expression of two proteins. The cloned citrate synthase promoter (PcitA) sequence was able to express bar coding sequence thereby conferring phosphinothricin resistance. This sequence was further analyzed by systematic deletions to define an effective but compact functional promoter. The PcitA driven egfp expression showed that PcitA was active in all differentiation cell-stages of A. niger. EGFP expression was highest on non-repressible carbon sources like acetate and glycerol. Mycelial EGFP levels increased during acidogenic growth suggesting that PcitA is functional throughout this cultivation. A. niger PcitA is the first Krebs cycle gene promoter used to express heterologous proteins in filamentous fungi.

  14. Strongly bound citrate stabilizes the apatite nanocrystals in bone

    SciTech Connect

    Hu, Y.-Y.; Rawal, A.; Schmidt-Rohr, K.

    2010-10-12

    Nanocrystals of apatitic calcium phosphate impart the organic-inorganic nanocomposite in bone with favorable mechanical properties. So far, the factors preventing crystal growth beyond the favorable thickness of ca. 3 nm have not been identified. Here we show that the apatite surfaces are studded with strongly bound citrate molecules, whose signals have been identified unambiguously by multinuclear magnetic resonance (NMR) analysis. NMR reveals that bound citrate accounts for 5.5 wt% of the organic matter in bone and covers apatite at a density of about 1 molecule per (2 nm){sup 2}, with its three carboxylate groups at distances of 0.3 to 0.45 nm from the apatite surface. Bound citrate is highly conserved, being found in fish, avian, and mammalian bone, which indicates its critical role in interfering with crystal thickening and stabilizing the apatite nanocrystals in bone

  15. Supplementation of total parenteral nutrition solutions with ferrous citrate.

    PubMed

    Sayers, M H; Johnson, D K; Schumann, L A; Ivey, M F; Young, J H; Finch, C A

    1983-01-01

    Daily infusion of a total parenteral nutrition (TPN) formulation containing 1 liter of 5.5% Travasol provides less than 0.1 milligrams of iron. By comparison, a formulation which includes a liter of 10% Travamin provides 2 milligrams of iron per day. To meet iron requirements in patients infusing formulations containing Travasol, iron was added as ferrous citrate. In in virto experiments, 74% of this iron was available to transferrin. In seven patients in whom in vivo availability was tested by red cell incorporation, the mean availability was 81%. Ferrous citrate is recommended as a safe, effective additive to TPN solutions for adult patients requiring iron supplements.

  16. Long-term Stability of Esomeprazole in 5% Dextrose Infusion Polyolefin Bags at 5 degrees C +/- 3 degrees C after Microwave Freeze-thaw Treatment.

    PubMed

    Hecq, Jean-daniel; Rolin, Catherine; Godet, Marie; Gillet, Patricia; Jamart, Jacques; Galanti, Laurence M

    2015-01-01

    To improve quality assurance, security, time management, and cost saving of drug delivery, preparation in advance of intravenous solutions has been developed for several infusion solutions. The objective of this study was to investigate the stability of esomeprazole 0.4 mg/mL and 0.8 mg/mL in 5% dextrose polyolefin bags after freezing, long-term storage, and microwave thawing. The stability of five polyolefin bags containing approximately 0.4 mg/mL of esomeprazole and five other bags containing approximately 0.8 mg/mL in 5% dextrose prepared under aseptic conditions was studied after freezing for 1 month at -20 degrees C, thawing in a microwave oven with a validated cycle, and stored at 5 degrees C +/- 3 degrees C. Esomeprazole concentration was measured by high-pressure liquid chromatography using a reversed-phase column C8, a mobile phase consisting of 35% of acetonitrile and 65% of Na2HPO4 buffer at pH 7.59 with HPO4 (2 M) and NaOH (0.5 M), and detection with a diode array detector at 280 nm. Visual, microscopic, and spectrophotometric observation and pH measurements were also performed. No precipitation occurred in the preparations but little change of color was observed. No microaggregate was observed with optical microscopy or revealed by a change of absorbance at 350, 410, and 550 nm. Based on a shelf life of 90% residual potency, esomeprazole solutions (0.4 and 0.8 mg/mL) were stable for at least 20 or 29 days, respectively, after a freezing and microwave thawing period, where 95% one-side lower confidence limit of the concentration-time profile remained superior to 90% of the initial concentration. During this period, the pH values of drug solutions have been observed to decrease without affecting chromatographic parameters. Within these limits, esomeprazole (0.4 and 0.8 mg/mL) in 5% dextrose infusions may be prepared and frozen in advance by a centralized intravenous admixture service, thawed, and stored at least 20 days at 5 degrees C +/- 3 degrees C

  17. The periplasmic domain of the histidine autokinase CitA functions as a highly specific citrate receptor.

    PubMed

    Kaspar, S; Perozzo, R; Reinelt, S; Meyer, M; Pfister, K; Scapozza, L; Bott, M

    1999-08-01

    The two-component regulatory system CitA/CitB is essential for induction of the citrate fermentation genes in Klebsiella pneumoniae. CitA represents a membrane-bound sensor kinase consisting of a periplasmic domain flanked by two transmembrane helices, a linker domain and the conserved kinase or transmitter domain. A fusion protein (MalE-CitAC) composed of the maltose-binding protein and the CitA kinase domain (amino acids 327-547) showed constitutive autokinase activity and transferred the gamma-phosphate group of ATP to its cognate response regulator CitB. The autokinase activity of CitA was abolished by an H350L exchange, and phosphorylation of CitB was inhibited by a D56N exchange, indicating that H-350 and D-56 represent the phosphorylation sites of CitA and CitB respectively. In the presence of ATP, CitB-D56N formed a stable complex with MalE-CitAC. To analyse the sensory properties of CitA, the periplasmic domain (amino acids 45-176) was overproduced as a soluble, cytoplasmic protein with a C-terminally attached histidine tag (CitAPHis). Purified CitAPHis bound citrate, but none of the other tri- and dicarboxylates tested, with high affinity (KD approximately 5 microM at pH 7) in a 1:1 stoichiometry. As shown by isothermal titration calorimetry, the binding reaction was driven by the enthalpy change (DeltaH = -76.3 kJ mol-1), whereas the entropy change was opposed (-TDeltaS = + 46.3 kJ mol-1). The pH dependency of the binding reaction indicated that the dianionic form H-citrate2- is the citrate species recognized by CitAPHis. In the presence of Mg2+ ions, the dissociation constant increased significantly, suggesting that the Mg-citrate complex is not bound by CitAPHis. This work defines the periplasmic domain of CitA as a highly specific citrate receptor and elucidates the binding characteristics of CitAPHis.

  18. The sensor kinase CitA (DpiB) of Escherichia coli functions as a high-affinity citrate receptor.

    PubMed

    Kaspar, Sibylle; Bott, Michael

    2002-04-01

    For the CitA-CitB (DpiB-DpiA) two-component signal transduction system from Escherichia coli, three diverse functions have been reported: induction of the citrate fermentation genes citCDEFXGT, repression of the regulator gene appY, and destabilization of the inheritance of iteron-containing plasmids such as pSC101. This poses the question of the principal biological role of this system. Here it is shown that the periplasmic domain of the E. coli sensor kinase CitA functions as a high-affinity citrate receptor. Two CitA derivatives were purified by affinity chromatography and subjected to binding studies using isothermal titration calorimetry (ITC). One of them, termed CitA215MBP, comprised the N-terminal part of CitA (amino acid residues 1-215), including the two transmembrane helices, and was fused to the amino terminus of the E. coli maltose-binding protein lacking its signal peptide. The second CitA derivative, designated CitAP(Ec), encompassed only the periplasmic domain (amino acid residues 38-177). CitA215MBP bound citrate at 25 degrees C with a K(d) of 0.3 microM and a binding stoichiometry of up to 0.9 in 50 mM sodium phosphate buffer, pH 7. Binding was driven by the enthalpy change (Delta H of -95.7 kJ mol(-1)), whereas the entropy change was not favorable for binding ( T Delta S of -58.6 kJ mol(-1)). ITC experiments with CitAP(Ec) yielded similar K(d) values for citrate (0.15-1.0 microM). Besides citrate, also isocitrate ( K(d) approximately tricarballylate ( K(d) approximately t not malate were bound by CitAP(Ec). The results favor the assumption that the primary biological function of the CitA-CitB system is the regulation of the citrate fermentation genes.

  19. 21 CFR 172.832 - Monoglyceride citrate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... FOR HUMAN CONSUMPTION (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN... glyceryl monooleate and its citric acid monoester manufactured by the reaction of glyceryl monooleate with... addition to oils and fats whereby the additive does not exceed 200 parts per million of the combined...

  20. 21 CFR 172.832 - Monoglyceride citrate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Multipurpose Additives § 172.832... manufactured by the reaction of glyceryl monooleate with citric acid under controlled conditions may be safely... use, in antioxidant formulations for addition to oils and fats whereby the additive does not...

  1. Effect of the Food Additives Sodium Citrate and Disodium Phosphate on Shiga Toxin-Producing Escherichia coli and Production of stx-Phages and Shiga toxin

    PubMed Central

    Lenzi, Lucas J.; Lucchesi, Paula M. A.; Medico, Lucía; Burgán, Julia; Krüger, Alejandra

    2016-01-01

    Induction and propagation of bacteriophages along the food production chain can represent a significant risk when bacteriophages carry genes for potent toxins. The aim of this study was to evaluate the effect of different compounds used in the food industry on the growth of Shiga toxin-producing Escherichia coli (STEC) and the production of stx-phage particles and Shiga toxin. We tested the in vitro effect of lactic acid, acetic acid, citric acid, disodium phosphate, and sodium citrate on STEC growth. A bacteriostatic effect was observed in most of treated cultures. The exceptions were those treated with sodium citrate and disodium phosphate in which similar growth curves to the untreated control were observed, but with reduced OD600 values. Evaluation of phage production by plaque-based assays showed that cultures treated with sodium citrate and disodium phosphate released phages in similar o lower levels than untreated cultures. However, semi-quantification of Stx revealed higher levels of extracellular Stx in STEC cultures treated with 2.5% sodium citrate than in untreated cultures. Our results reinforce the importance to evaluate if additives and other treatments used to decrease bacterial contamination in food induce stx-phage and Stx production. PMID:27446032

  2. Effect of the Food Additives Sodium Citrate and Disodium Phosphate on Shiga Toxin-Producing Escherichia coli and Production of stx-Phages and Shiga toxin.

    PubMed

    Lenzi, Lucas J; Lucchesi, Paula M A; Medico, Lucía; Burgán, Julia; Krüger, Alejandra

    2016-01-01

    Induction and propagation of bacteriophages along the food production chain can represent a significant risk when bacteriophages carry genes for potent toxins. The aim of this study was to evaluate the effect of different compounds used in the food industry on the growth of Shiga toxin-producing Escherichia coli (STEC) and the production of stx-phage particles and Shiga toxin. We tested the in vitro effect of lactic acid, acetic acid, citric acid, disodium phosphate, and sodium citrate on STEC growth. A bacteriostatic effect was observed in most of treated cultures. The exceptions were those treated with sodium citrate and disodium phosphate in which similar growth curves to the untreated control were observed, but with reduced OD600 values. Evaluation of phage production by plaque-based assays showed that cultures treated with sodium citrate and disodium phosphate released phages in similar o lower levels than untreated cultures. However, semi-quantification of Stx revealed higher levels of extracellular Stx in STEC cultures treated with 2.5% sodium citrate than in untreated cultures. Our results reinforce the importance to evaluate if additives and other treatments used to decrease bacterial contamination in food induce stx-phage and Stx production.

  3. 40 CFR 721.7286 - Amines, N-tallowalkyltripropylenetetra-, citrates.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Amines, N-tallowalkyltripropylenetetra... Specific Chemical Substances § 721.7286 Amines, N-tallowalkyltripropylenetetra-, citrates. (a) Chemical substances and significant new uses subject to reporting. (1) The chemical substance identified as amines,...

  4. 40 CFR 721.7285 - Amines, N-cocoalkyltrimethylenedi-, citrates.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Amines, N-cocoalkyltrimethylenedi... Specific Chemical Substances § 721.7285 Amines, N-cocoalkyltrimethylenedi-, citrates. (a) Chemical substances and significant new uses subject to reporting. (1) The chemical substance identified as amines,...

  5. 40 CFR 721.7285 - Amines, N-cocoalkyltrimethylenedi-, citrates.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Amines, N-cocoalkyltrimethylenedi... Specific Chemical Substances § 721.7285 Amines, N-cocoalkyltrimethylenedi-, citrates. (a) Chemical substances and significant new uses subject to reporting. (1) The chemical substance identified as amines,...

  6. 40 CFR 721.7286 - Amines, N-tallowalkyltripropylenetetra-, citrates.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Amines, N-tallowalkyltripropylenetetra... Specific Chemical Substances § 721.7286 Amines, N-tallowalkyltripropylenetetra-, citrates. (a) Chemical substances and significant new uses subject to reporting. (1) The chemical substance identified as amines,...

  7. 40 CFR 721.7285 - Amines, N-cocoalkyltrimethylenedi-, citrates.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Amines, N-cocoalkyltrimethylenedi... Specific Chemical Substances § 721.7285 Amines, N-cocoalkyltrimethylenedi-, citrates. (a) Chemical substances and significant new uses subject to reporting. (1) The chemical substance identified as amines,...

  8. 40 CFR 721.7285 - Amines, N-cocoalkyltrimethylenedi-, citrates.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Amines, N-cocoalkyltrimethylenedi... Specific Chemical Substances § 721.7285 Amines, N-cocoalkyltrimethylenedi-, citrates. (a) Chemical substances and significant new uses subject to reporting. (1) The chemical substance identified as amines,...

  9. 40 CFR 721.7286 - Amines, N-tallowalkyltripropylenetetra-, citrates.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Amines, N-tallowalkyltripropylenetetra... Specific Chemical Substances § 721.7286 Amines, N-tallowalkyltripropylenetetra-, citrates. (a) Chemical substances and significant new uses subject to reporting. (1) The chemical substance identified as amines,...

  10. 40 CFR 721.7286 - Amines, N-tallowalkyltripropylenetetra-, citrates.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Amines, N-tallowalkyltripropylenetetra... Specific Chemical Substances § 721.7286 Amines, N-tallowalkyltripropylenetetra-, citrates. (a) Chemical substances and significant new uses subject to reporting. (1) The chemical substance identified as amines,...

  11. Development of Injectable Citrate-Based Bioadhesive Bone Implants

    PubMed Central

    Xie, Denghui; Guo, Jinshan; Mehdizadeh, Mohammadreza; Tran, Richard T.; Chen, Ruisong; Sun, Dawei; Qian, Guoying; Jin, Dadi; Bai, Xiaochun; Yang, Jian

    2014-01-01

    Injectable bone implants have been widely used in bone tissue repairs including the treatment of comminuted bone fractures (CBF). However, most injectable bone implants are not suitable for the treatment of CBF due to their weak tissue adhesion strengths and minimal osteoinduction. Citrate has been recently reported to promote bone formation through enhanced bioceramic integration and osteoinductivity. Herein, a novel injectable citrate-based mussel-inspired bioadhesive hydroxyapatite (iCMBA/HA) bone substitute was developed for CBF treatment. iCMBA/HA can be set within 2–4 minutes and the as-prepared (wet) iCMBA/HA possess low swelling ratios, compressive mechanical strengths of up to 3.2±0.27 MPa, complete degradation in 30 days, suitable biocompatibility, and osteoinductivity. This is also the first time to demonstrate that citrate supplementation in osteogenic medium and citrate released from iCMBA/HA degradation can promote the mineralization of osteoblastic committed human mesenchymal stem cells (hMSCs). In vivo evaluation of iCMBA/HA in a rabbit comminuted radial fracture model showed significantly increased bone formation with markedly enhanced three-point bending strength compared to the negative control. Neovascularization and bone ingrowth as well as highly organized bone formation were also observed showing the potential of iCMBA/HA in treating CBF. PMID:25580247

  12. 21 CFR 522.300 - Carfentanil citrate injection.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Carfentanil citrate injection. 522.300 Section 522.300 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL DRUGS §...

  13. 21 CFR 522.300 - Carfentanil citrate injection.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Carfentanil citrate injection. 522.300 Section 522.300 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL DRUGS §...

  14. 21 CFR 522.300 - Carfentanil citrate injection.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Carfentanil citrate injection. 522.300 Section 522.300 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL DRUGS §...

  15. 21 CFR 573.560 - Iron ammonium citrate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Iron ammonium citrate. 573.560 Section 573.560 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS...

  16. 21 CFR 573.560 - Iron ammonium citrate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Iron ammonium citrate. 573.560 Section 573.560 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS...

  17. 21 CFR 573.560 - Iron ammonium citrate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Iron ammonium citrate. 573.560 Section 573.560 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS...

  18. 21 CFR 573.560 - Iron ammonium citrate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Iron ammonium citrate. 573.560 Section 573.560 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS...

  19. 21 CFR 520.623 - Diethylcarbamazine citrate, oxibendazole chewable tablets.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Diethylcarbamazine citrate, oxibendazole chewable tablets. 520.623 Section 520.623 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... during heartworm season. For free-choice feeding or broken and placed on or mixed with feed. Do not...

  20. 21 CFR 520.622 - Diethylcarbamazine citrate oral dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Diethylcarbamazine citrate oral dosage forms. 520.622 Section 520.622 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS §...

  1. 21 CFR 522.800 - Droperidol and fentanyl citrate injection.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Droperidol and fentanyl citrate injection. 522.800 Section 522.800 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL...

  2. 21 CFR 522.300 - Carfentanil citrate injection.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Carfentanil citrate injection. 522.300 Section 522.300 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL DRUGS §...

  3. 21 CFR 522.800 - Droperidol and fentanyl citrate injection.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Droperidol and fentanyl citrate injection. 522.800 Section 522.800 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL...

  4. Complex transcriptional regulation of citrate metabolism in Clostridium perfringens.

    PubMed

    Yuan, Yonghui; Ohtani, Kaori; Yoshizawa, Satoko; Shimizu, Tohru

    2012-02-01

    A Gram-positive, spore-forming bacterium, Clostridium perfringens, possesses genes for citrate metabolism, which might play an important role in the utilization of citrate as a sole carbon source. In this study, we identified a chromosomal citCDEFX-mae-citS operon in C. perfringens strain 13, which is transcribed on three mRNAs of different sizes. Expression of the cit operon was significantly induced when 5 mM extracellular citrate was added to the growth medium. Most interestingly, three regulatory systems were found to be involved in the regulation of the expression of cit genes: 1) the two upstream divergent genes citG and citI; 2) two different two-component regulatory systems, CitA/CitB (TCS6 consisted of CPE0531/CPE0532) and TCS5 (CPE0518/CPE0519); and 3) the global two-component VirR/VirS-VR-RNA regulatory system known to regulate various genes for toxins and degradative enzymes. Our results suggest that in C. perfringens the citrate metabolism might be strictly controlled by a complex regulatory system.

  5. 21 CFR 184.1296 - Ferric ammonium citrate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... FOR HUMAN CONSUMPTION (CONTINUED) DIRECT FOOD SUBSTANCES AFFIRMED AS GENERALLY RECOGNIZED AS SAFE... brown or garnet red scales or granules or as a brownish-yellowish powder. (2) Ferric ammonium citrate... occurs as thin transparent green scales, as granules, as a powder, or as transparent green crystals....

  6. 21 CFR 184.1296 - Ferric ammonium citrate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... FOR HUMAN CONSUMPTION (CONTINUED) DIRECT FOOD SUBSTANCES AFFIRMED AS GENERALLY RECOGNIZED AS SAFE... brown or garnet red scales or granules or as a brownish-yellowish powder. (2) Ferric ammonium citrate... occurs as thin transparent green scales, as granules, as a powder, or as transparent green crystals....

  7. 40 CFR 721.7286 - Amines, N-tallowalkyltripropylenetetra-, citrates.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Amines, N-tallowalkyltripropylenetetra... Specific Chemical Substances § 721.7286 Amines, N-tallowalkyltripropylenetetra-, citrates. (a) Chemical substances and significant new uses subject to reporting. (1) The chemical substance identified as amines,...

  8. 40 CFR 721.7285 - Amines, N-cocoalkyltrimethylenedi-, citrates.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Amines, N-cocoalkyltrimethylenedi... Specific Chemical Substances § 721.7285 Amines, N-cocoalkyltrimethylenedi-, citrates. (a) Chemical substances and significant new uses subject to reporting. (1) The chemical substance identified as amines,...

  9. 21 CFR 520.622d - Diethylcarbamazine citrate capsules.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... Diethylcarbamazine citrate capsules. (a) Specifications. Each capsule contains 12.5, 50, 200, or 400 milligrams (mg... dogs—(1) Amount/indications for use. 3 mg per pound (/lb) body weight daily for prevention of heartworm disease (Dirofilaria immitis); 25 to 50 mg/lb body weight in a single dose as an aid in the treatment...

  10. 21 CFR 520.622d - Diethylcarbamazine citrate capsules.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Diethylcarbamazine citrate capsules. (a) Specifications. Each capsule contains 12.5, 50, 200, or 400 milligrams (mg... dogs—(1) Amount/indications for use. 3 mg per pound (/lb) body weight daily for prevention of heartworm disease (Dirofilaria immitis); 25 to 50 mg/lb body weight in a single dose as an aid in the treatment...

  11. 75 FR 14491 - Listing of Color Additives Exempt From Certification; Bismuth Citrate

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-26

    ... level of bismuth citrate as a color additive in cosmetics intended for coloring hair on the scalp. This... citrate as a color additive in cosmetics intended for coloring hair on the scalp from 0.5 percent (weight... bismuth citrate in cosmetics intended for coloring scalp hair to 2.0 percent (w/v) with no changes to...

  12. 78 FR 63228 - Determination That Potassium Citrate, 10 Milliequivalents/Packet and 20 Milliequivalents/Packet...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-23

    ... HUMAN SERVICES Food and Drug Administration Determination That Potassium Citrate, 10 Milliequivalents...) has determined that Potassium Citrate, 10 milliequivalents/packet (mEq/packet) and 20 mEq/ packet, was... approve abbreviated new drug applications (ANDAs) for Potassium Citrate, 10 mEq/packet and 20...

  13. Citrate and malonate increase microbial activity and alter microbial community composition in uncontaminated and diesel-contaminated soil microcosms

    NASA Astrophysics Data System (ADS)

    Martin, Belinda C.; George, Suman J.; Price, Charles A.; Shahsavari, Esmaeil; Ball, Andrew S.; Tibbett, Mark; Ryan, Megan H.

    2016-09-01

    Petroleum hydrocarbons (PHCs) are among the most prevalent sources of environmental contamination. It has been hypothesized that plant root exudation of low molecular weight organic acid anions (carboxylates) may aid degradation of PHCs by stimulating heterotrophic microbial activity. To test their potential implication for bioremediation, we applied two commonly exuded carboxylates (citrate and malonate) to uncontaminated and diesel-contaminated microcosms (10 000 mg kg-1; aged 40 days) and determined their impact on the microbial community and PHC degradation. Every 48 h for 18 days, soil received 5 µmol g-1 of (i) citrate, (ii) malonate, (iii) citrate + malonate or (iv) water. Microbial activity was measured daily as the flux of CO2. After 18 days, changes in the microbial community were assessed by a community-level physiological profile (CLPP) and 16S rRNA bacterial community profiles determined by denaturing gradient gel electrophoresis (DGGE). Saturated PHCs remaining in the soil were assessed by gas chromatography-mass spectrometry (GC-MS). Cumulative soil respiration increased 4- to 6-fold with the addition of carboxylates, while diesel contamination resulted in a small, but similar, increase across all carboxylate treatments. The addition of carboxylates resulted in distinct changes to the microbial community in both contaminated and uncontaminated soils but only a small increase in the biodegradation of saturated PHCs as measured by the n-C17 : pristane biomarker. We conclude that while the addition of citrate and malonate had little direct effect on the biodegradation of saturated hydrocarbons present in diesel, their effect on the microbial community leads us to suggest further studies using a variety of soils and organic acids, and linked to in situ studies of plants, to investigate the role of carboxylates in microbial community dynamics.

  14. Some factors affecting cyclopropane acid formation in Escherichia coli

    PubMed Central

    Knivett, V. A.; Cullen, Julia

    1965-01-01

    1. The fatty acid composition of the extractable lipids of Escherichia coli varied with growth conditions. 2. The principal fatty acids were palmitic acid, hexadecenoic acid, octadecenoic acid and the cyclopropane acids, methylenehexadecanoic acid and methyleneoctadecanoic acid. 3. Cyclopropane acid formation from monoenoic acids was increased by acid media, poor oxygen supply, or high growth temperature. 4. Cyclopropane acid formation was decreased by alkaline media, well oxygenated conditions, the presence of citrate, or lack of Mg2+. PMID:5324304

  15. Effects of citric acid esterification on digestibility, structural and physicochemical properties of cassava starch.

    PubMed

    Mei, Ji-Qiang; Zhou, Da-Nian; Jin, Zheng-Yu; Xu, Xue-Ming; Chen, Han-Qing

    2015-11-15

    In this study, citric acid was used to react with cassava starch in order to compare the digestibility, structural and physicochemical properties of citrate starch samples. The results indicated that citric acid esterification treatment significantly increased the content of resistant starch (RS) in starch samples. The swelling power and solubility of citrate starch samples were lower than those of native starch. Compared with native starch, a new peak at 1724 cm(-1) was appeared in all citrate starch samples, and crystalline peaks of all starch citrates became much smaller or even disappeared. Differential scanning calorimetry results indicated that the endothermic peak of citrate starches gradually shrank or even disappeared. Moreover, the citrate starch gels exhibited better freeze-thaw stability. These results suggested that citric acid esterification induced structural changes in cassava starch significantly affected its digestibility and it could be a potential method for the preparation of RS with thermal stability.

  16. Effect of trisodium citrate concentration and cooking time on the physicochemical properties of pasteurized process cheese.

    PubMed

    Shirashoji, N; Jaeggi, J J; Lucey, J A

    2006-01-01

    The effects of the concentration of trisodium citrate (TSC) emulsifying salt (0.25 to 2.75%) and holding time (0 to 20 min) on the textural, rheological, and microstructural properties of pasteurized process Cheddar cheese were studied using a central composite rotatable design. The loss tangent parameter (from small amplitude oscillatory rheology), extent of flow (derived from the University of Wisconsin Meltprofiler), and melt area (from the Schreiber test) all indicated that the meltability of process cheese decreased with increased concentration of TSC and that holding time led to a slight reduction in meltability. Hardness increased as the concentration of TSC increased. Fluorescence micrographs indicated that the size of fat droplets decreased with an increase in the concentration of TSC and with longer holding times. Acid-base titration curves indicated that the buffering peak at pH 4.8, which is due to residual colloidal calcium phosphate, decreased as the concentration of TSC increased. The soluble phosphate content increased as concentration of TSC increased. However, the insoluble Ca decreased with increasing concentration of TSC. The results of this study suggest that TSC chelated Ca from colloidal calcium phosphate and dispersed casein; the citrate-Ca complex remained trapped within the process cheese matrix. Increasing the concentration of TSC helped to improve fat emulsification and casein dispersion during cooking, both of which probably helped to reinforce the structure of process cheese.

  17. Modification by food of the calcium absorbability and physicochemical effects of calcium citrate

    NASA Technical Reports Server (NTRS)

    Wabner, C. L.; Pak, C. Y.

    1992-01-01

    The food-calcium (Ca) interaction was examined in 12 healthy women (mean age 38 years) maintained on a constant metabolic diet. They underwent three phases of study, comprised of control (no Ca), Ca citrate (1 g Ca/day) during meals, and Ca citrate separately from meals. Each phase was 7 days in length and two 24-hour urine samples were collected on days 6 and 7. The rise from the control phase in urinary Ca was slightly more prominent when Ca citrate was given with meals than without (68 and 62%, respectively). The fall in urinary phosphorus was equivalent at about 25% between Ca citrate phases. The rise in urinary citrate and pH and the decline in urinary ammonium were more prominent when Ca citrate was given with meals; however, the changes were small or nonsignificant. The urinary saturation of Ca oxalate, brushite or monosodium urate did not differ between the two Ca citrate phases. There was a nonsignificant rise in serum iron during Ca citrate phases. The results suggest that: 1) dissolution and absorption of Ca citrate might be slightly greater when given with food than without; 2) that the ability of Ca citrate to attenuate crystallization of stone-forming Ca salts in urine is not modified by food; and 3) that Ca citrate may not impair iron absorption from food.

  18. Chitosan citrate as film former: compatibility with water-soluble anionic dyes and drug dissolution from coated tablet.

    PubMed

    Phaechamud, T; Koizumi, T; Ritthidej, G C

    2000-03-30

    Chitosan citrate solution containing 25% w/w propylene glycol was prepared and tested for its compatibility with some water soluble anionic dyes. The immiscibility between erythrosine, ponceau 4R, sunset yellow or tartrazine solutions and chitosan citrate solution was evident. The Fourier transform-infrared spectra revealed charged interaction between anionic dye and chitosan. Brilliant blue and green FS at concentration of 0.02-1.00% w/w polymer could be miscible with chitosan citrate solution due to the decrease in charge interaction by the positive charge on molecule of brilliant blue, which was also the composition in green FS. Propranolol HCl tablets coated with these colored film-coating solutions exhibited good appearance and no color migration. Drug dissolution from coated tablets was pH dependent, corresponding to the ability of chitosan to protonate in the medium. Color incorporation slightly retarded drug dissolution in acidic medium. Drug dissolved from coated tablet colored with brilliant blue was faster than from that colored with green FS. This was because brilliant blue had positive charge and more SO(3)H groups on its molecular structure, and exhibited higher water solubility. Accelerated condition could alter dissolution characteristics, and the Td+t(0) value from curve fitting between the dissolution profiles and Weibull equation was increased. However, drug dissolution from freshly prepared coated tablets, coated tablets after exposure to accelerated condition and after storage at room temperature for 12 months conformed to the monograph in USP XXIII.

  19. Citrate sensing by the C4-dicarboxylate/citrate sensor kinase DcuS of Escherichia coli: binding site and conversion of DcuS to a C4-dicarboxylate- or citrate-specific sensor.

    PubMed

    Krämer, J; Fischer, J D; Zientz, E; Vijayan, V; Griesinger, C; Lupas, A; Unden, G

    2007-06-01

    The histidine protein kinase DcuS of Escherichia coli senses C(4)-dicarboxylates and citrate by a periplasmic domain. The closely related sensor kinase CitA binds citrate, but no C(4)-dicarboxylates, by a homologous periplasmic domain. CitA is known to bind the three carboxylate and the hydroxyl groups of citrate by sites C1, C2, C3, and H. DcuS requires the same sites for C(4)-dicarboxylate sensing, but only C2 and C3 are highly conserved. It is shown here that sensing of citrate by DcuS required the same sites. Binding of citrate to DcuS, therefore, was similar to binding of C(4)-dicarboxylates but different from that of citrate binding in CitA. DcuS could be converted to a C(4)-dicarboxylate-specific sensor (DcuS(DC)) by mutating residues of sites C1 and C3 or of some DcuS-subtype specific residues. Mutations around site C1 aimed at increasing the size and accessibility of the site converted DcuS to a citrate-specific sensor (DcuS(Cit)). DcuS(DC) and DcuS(Cit) had complementary effector specificities and responded either to C(4)-dicarboxylates or to citrate and mesaconate. The results imply that DcuS binds citrate (similar to the C(4)-dicarboxylates) via the C(4)-dicarboxylate part of the molecule. Sites C2 and C3 are essential for binding of two carboxylic groups of citrate or of C(4)-dicarboxylates; sites C1 and H are required for other essential purposes.

  20. The contribution of stored malate and citrate to the substrate requirements of metabolism of ripening peach (Prunus persica L. Batsch) flesh is negligible. Implications for the occurrence of phosphoenolpyruvate carboxykinase and gluconeogenesis.

    PubMed

    Famiani, Franco; Farinelli, Daniela; Moscatello, Stefano; Battistelli, Alberto; Leegood, Richard C; Walker, Robert P

    2016-04-01

    The first aim of this study was to determine the contribution of stored malate and citrate to the substrate requirements of metabolism in the ripening flesh of the peach (Prunus persica L. Batsch) cultivar Adriatica. In the flesh, stored malate accumulated before ripening could contribute little or nothing to the net substrate requirements of metabolism. This was because there was synthesis and not dissimilation of malate throughout ripening. Stored citrate could potentially contribute a very small amount (about 5.8%) of the substrate required by metabolism when the whole ripening period was considered, and a maximum of about 7.5% over the latter part of ripening. The second aim of this study was to investigate why phosphoenolpyruvate carboxykinase (PEPCK) an enzyme utilised in gluconeogenesis from malate and citrate is present in peach flesh. The occurrence and localisation of enzymes utilised in the metabolism of malate, citrate and amino acids were determined in peach flesh throughout its development. Phosphoenolpyruvate carboxylase (essential for the synthesis of malate and citrate) was present in the same cells and at the same time as PEPCK and NADP-malic enzyme (both utilised in the dissimilation of malate and citrate). A hypothesis is presented to explain the presence of these enzymes and to account for the likely occurrence of gluconeogenesis.

  1. Trisodium citrate, Na3(C6H5O7)

    PubMed Central

    Rammohan, Alagappa; Kaduk, James A.

    2016-01-01

    The crystal structure of anhydrous tris­odium citrate, Na3(C6H5O7), has been solved and refined using synchrotron X-ray powder diffraction data, and optimized using density functional theory (DFT). There are two independent five-coordinate Na+ and one six-coordinate Na+ cations in the asymmetric unit. The [NaO5] and [NaO6] polyhedra share edges and corners to form a three-dimensional framework. There are channels parallel to the a and b axes in which the remainder of the citrate anions reside. The only hydrogen bonds are an intra­molecular one between the hy­droxy group and one of the terminal carboxyl­ate O atoms and an intermolecular one between a methylene group and the hydroxyl O atom. PMID:27308044

  2. Calcium citrate for vulvar vestibulitis. A case report.

    PubMed

    Solomons, C C; Melmed, M H; Heitler, S M

    1991-12-01

    A woman had suffered from vulvar vestibulitis (vulvodynia) for four years. Pain from the disorder had disrupted her ability to function at work and home as well as sexually. An initial full range of treatments, including multiple operations, had produced no relief. Examination of the urine for evidence of excess oxalate, which has been shown to cause epithelial reactions similar to those found in vulvodynia, showed periodic hyperoxaluria and pH elevations related to the symptoms. Calcium citrate was given to modify the oxalate crystalluria. The symptoms were significantly reduced in three months, and the patient was pain free after one year. She was able to resume normal work, family, sexual and recreational activities. Withdrawal of the calcium citrate resulted in a return of the symptoms; reinstitution alleviated them. These findings suggest that further study of individualized metabolic factors that may underlie vulvodynia is warranted.

  3. Clomiphene citrate and its effects upon ovulation and estrogen.

    PubMed

    Shirai, E; Iizuka, R; Notake, Y

    1972-05-01

    This paper reports a clinical evaluation of the mechanism of action of clomiphene citrate and describes selection of the most responsive patients. Patients were 121 women, aged 21-37 years, who desired pregnancy. Their infertility was diagnosed as being due to anovulation. Primary amenorrhea or special endocrine disorders were not present. All the women who had no vaginal bleeding for more than 2 months were diagnosed amenorrhea and treated with 65 mg of progesterone capronate intramuscularly. They were then divided into two subgroups on the basis of the presence or absence of vaginal bleeding within 2 weeks. Clinical studies included: basal body temperature charts; daily vaginal smears evaluated by the ink acidophilic stain index (ISI); cervical mucus evaluated by amount, spresence of spinnbarkeit, and ferning; 24-hour urines examined for estrogen and total gonadotropic activity; and a pregnanediol determination. Each group received daily 50 mg doses of clomiphene citrate for 5 days. Estrogen inhibiting effect of the drug was suggested by vaginal cytology and the disappearance of ferning and decrease in quantity of cervical mucus. However, the excretion of the total urinary estrogen was increased in ovulatory cases (81 of the 121 patients). In 17 patients having no bleeding within 2 weeks after progesterone injection no ovulation could be induced. In patients with withdrawal flow 54 of 70 achieved ovulation. Of 37 patients with previous anovulatory bleeding 27 achieved ovulation. There were 11 of the 121 who became pregnant. In those with early ovulation the antiestrogen effect is believed to be in the hypothalamus and pituitary bringing about the estrogen surge and stimulating LH secretion. In those with later ovulation the antiestrogenic effect increased FSH secretion followed by ovulation. The type of patient most likely to respond to clomiphene citrate is one with nearly normal pituitary-gonadal axis. Inducing withdrawal bleeding with progesterone in those

  4. Severe citrate toxicity complicating volunteer apheresis platelet donation.

    PubMed

    Bell, A M; Nolen, J D L; Knudson, C M; Raife, T J

    2007-02-01

    We report a case of severe citrate toxicity during volunteer donor apheresis platelet collection. The donor was a 40-year-old female, first-time apheresis platelet donor. Past medical history was remarkable for hypertension, hyperlipidemia, and depression. Reported medications included bumetanide, pravastatin, and paroxetine. Thirty minutes from the start of the procedure, the donor noted tingling around the mouth, hands, and feet. She then very rapidly developed acute onset of severe facial and extremity tetany. Empirical treatment with intravenous calcium gluconate was initiated, and muscle contractions slowly subsided over approximately 10 to 15 minutes. The events are consistent with a severe reaction to calcium chelation by sodium citrate anticoagulant resulting in symptomatic systemic hypocalcemia. Upon additional retrospective analysis, it was noted that bumetanide is a loop diuretic that may cause significant hypocalcemia. We conclude that careful screening for medications and underlying conditions predisposing to hypocalcemia is recommended to help prevent severe reactions due to citrate toxicity. Laboratory measurement of pre-procedure serum calcium levels in selected donors may identify cases requiring heightened vigilance. The case also illustrates the importance of maintaining preparedness for managing rare but serious reactions in volunteer apheresis blood donors.

  5. Exogenous citrate impairs glucose tolerance and promotes visceral adipose tissue inflammation in mice.

    PubMed

    Leandro, João G B; Espindola-Netto, Jair M; Vianna, Maria Carolina F; Gomez, Lilian S; DeMaria, Thaina M; Marinho-Carvalho, Monica M; Zancan, Patricia; Paula Neto, Heitor A; Sola-Penna, Mauro

    2016-03-28

    Overweight and obesity have become epidemic worldwide and are linked to sedentary lifestyle and the consumption of processed foods and drinks. Citrate is a metabolite that plays central roles in carbohydrate and lipid metabolism. In addition, citrate is the additive most commonly used by the food industry, and therefore is highly consumed. Extracellular citrate can freely enter the cells via the constitutively expressed plasma membrane citrate transporter. Within the cytosol, citrate is readily metabolised by ATP-citrate lyase into acetyl-CoA - the metabolic precursor of endogenously produced lipids and cholesterol. We therefore hypothesised that the citrate ingested from processed foods and drinks could contribute to increased postprandial fat production and weight gain. To test our hypothesis, we administered citrate to mice through their drinking water with or without sucrose and monitored their weight gain and other metabolic parameters. Our results showed that mice receiving citrate or citrate+sucrose did not show increased weight gain or an increase in the weight of the liver, skeletal muscles or adipose tissues (AT). Moreover, the plasma lipid profiles (TAG, total cholesterol, LDL and HDL) were similar across all groups. However, the group receiving citrate+sucrose showed augmented fasting glycaemia, glucose intolerance and the expression of pro-inflammatory cytokines (TNF-α, IL-1β, IL-6 and IL-10) in their AT. Therefore, our results suggest that citrate consumption contributes to increased AT inflammation and altered glucose metabolism, which is indicative of initial insulin resistance. Thus, citrate consumption could be a previously unknown causative agent for the complications associated with obesity.

  6. Optimization and validation of a rapid method to determine citrate and inorganic phosphate in milk by capillary electrophoresis.

    PubMed

    Izco, J M; Tormo, M; Harris, A; Tong, P S; Jimenez-Flores, R

    2003-01-01

    Quantification of phosphate and citrate compounds is very important because their distribution between soluble and colloidal phases of milk and their interactions with milk proteins influence the stability and some functional properties of dairy products. The aim of this work was to optimize and validate a capillary electrophoresis method for the rapid determination of these compounds in milk. Various parameters affecting analysis have been optimized, including type, composition, and pH of the electrolyte, and sample extraction. Ethanol, acetonitrile, sulfuric acid, water at 50 degrees C or at room temperature were tested as sample buffers (SB). Water at room temperature yielded the best overall results and was chosen for further validation. The extraction time was checked and could be shortened to less than 1 min. Also, sample preparation was simplified to pipet 12 microl of milk into 1 ml of water containing 20 ppm of tartaric acid as an internal standard. The linearity of the method was excellent (R2 > 0.999) with CV values of response factors <3%. The detection limits for phosphate and citrate were 5.1 and 2.4 nM, respectively. The accuracy of the method was calculated for each compound (103.2 and 100.3%). In addition, citrate and phosphate content of several commercial milk samples were analyzed by this method, and the results deviated less than 5% from values obtained when analyzing the samples by official methods. To study the versatility of the technique, other dairy productssuch as cream cheese, yogurt, or Cheddar cheese were analyzed and accuracy was similar to milk in all products tested. The procedure is rapid and offers a very fast and simple sample preparation. Once the sample has arrived at the laboratory, less than 5 min (including handling, preparation, running, integration, and quantification) are necessary to determine the concentration of citric acid and inorganic phosphate. Because of the speed and accuracy of this method, it is promising as an

  7. Gastroprotective effect of ranitidine bismuth citrate is associated with increased mucus bismuth concentration in rats.

    PubMed Central

    Tanaka, S; Guth, P H; Paulsen, G; Kaunitz, J D

    1996-01-01

    BACKGROUND: Antisecretory and bismuth compounds protect the gastric mucosa from injury resulting from non-steroidal anti-inflammatory drugs. AIM: To study the mechanism underlying the gastroprotective effects of ranitidine bismuth citrate (GG311) in rats. METHODS: Indomethacin rat injury model and in vivo microscopy in which acid output, surface cell intracellular pH (pHi), gastric mucus gel thickness, and mucosal blood flow were measured simultaneously. RESULTS: In injury studies, GG311 dose dependently protected against severe injury induced by indomethacin (60 mg/kg subcutaneously). In in vivo microscopic studies, indomethacin significantly decreased mucus gel thickness and increased the initial rate of acidification of gastric surface cells when the superfusate pH was lowered from 7.4 to 1.0, and impaired pHi during acid exposure. Indomethacin had no effect on mucosal blood flow or acid output. GG311 alone had no effect on gel thickness, blood flow, or pHi homeostasis during acid exposure, but improved the initial acidification rate and pHi during superfusion with pH 1.0 solutions in the presence of indomethacin. In separate experiments, indomethacin pretreatment considerably increased gastric mucus bismuth concentrations in rats given GG311. CONCLUSIONS: The gastroprotective effect of GG311 against indomethacin induced gastric injury is associated with high and prolonged gastric mucus bismuth concentrations, which may impair proton permeation across the mucus gel. PMID:8977335

  8. SbnG, a citrate synthase in Staphylococcus aureus: a new fold on an old enzyme.

    PubMed

    Kobylarz, Marek J; Grigg, Jason C; Sheldon, Jessica R; Heinrichs, David E; Murphy, Michael E P

    2014-12-05

    In response to iron deprivation, Staphylococcus aureus produces staphyloferrin B, a citrate-containing siderophore that delivers iron back to the cell. This bacterium also possesses a second citrate synthase, SbnG, that is necessary for supplying citrate to the staphyloferrin B biosynthetic pathway. We present the structure of SbnG bound to the inhibitor calcium and an active site variant in complex with oxaloacetate. The overall fold of SbnG is structurally distinct from TCA cycle citrate synthases yet similar to metal-dependent class II aldolases. Phylogenetic analyses revealed that SbnG forms a separate clade with homologs from other siderophore biosynthetic gene clusters and is representative of a metal-independent subgroup in the phosphoenolpyruvate/pyruvate domain superfamily. A structural superposition of the SbnG active site to TCA cycle citrate synthases and site-directed mutagenesis suggests a case for convergent evolution toward a conserved catalytic mechanism for citrate production.

  9. Phytic acid increases mucin and endogenous amino acid losses from the gastrointestinal tract of chickens.

    PubMed

    Onyango, Edward M; Asem, Elikplimi K; Adeola, Olayiwola

    2009-03-01

    The influence of the form of phytic acid on the regulation of mucin and endogenous losses of amino acids, nitrogen and energy in chickens was investigated. Forty-eight 10-week-old male broilers were grouped by weight into eight blocks of six cages with one bird per cage. Birds received by intubation six dextrose-based combinations of phytic acid and phytase arranged in a 3 x 2 factorial consisting of phytic acid form (no phytic acid, 1.0 g free phytic acid or 1.3 g magnesium-potassium phytate) and phytase (0 or 1000 units). Each bird received the assigned combination added to 25 g dextrose at each of the two feedings on the first day of experimentation. All excreta were collected continuously for 54 h following feeding and frozen until analysed. Frozen excreta were thawed, pooled for each bird, lyophilised, ground, and analysed for DM, energy, nitrogen, amino acids, mucin, and sialic and uric acids. Chickens fed either magnesium-potassium phytate or free phytic acid showed increased (P < 0.05) loss of crude mucin and sialic acid. The amount of crude mucin lost was significantly greater (P < 0.05) with magnesium-potassium phytate than with free phytic acid treatment. Both phytic acid treatments also increased (P < 0.05) endogenous loss of threonine, proline and serine. In conclusion, the form of phytic acid fed to chickens affects the extent of mucin and endogenous amino acid losses from the gastrointestinal tract.

  10. Engineering genetically encoded nanosensors for real-time in vivo measurements of citrate concentrations.

    PubMed

    Ewald, Jennifer C; Reich, Sabrina; Baumann, Stephan; Frommer, Wolf B; Zamboni, Nicola

    2011-01-01

    Citrate is an intermediate in catabolic as well as biosynthetic pathways and is an important regulatory molecule in the control of glycolysis and lipid metabolism. Mass spectrometric and NMR based metabolomics allow measuring citrate concentrations, but only with limited spatial and temporal resolution. Methods are so far lacking to monitor citrate levels in real-time in-vivo. Here, we present a series of genetically encoded citrate sensors based on Förster resonance energy transfer (FRET). We screened databases for citrate-binding proteins and tested three candidates in vitro. The citrate binding domain of the Klebsiella pneumoniae histidine sensor kinase CitA, inserted between the FRET pair Venus/CFP, yielded a sensor highly specific for citrate. We optimized the peptide linkers to achieve maximal FRET change upon citrate binding. By modifying residues in the citrate binding pocket, we were able to construct seven sensors with different affinities spanning a concentration range of three orders of magnitude without losing specificity. In a first in vivo application we show that E. coli maintains the capacity to take up glucose or acetate within seconds even after long-term starvation.

  11. Buffer-stimulated citrate efflux in Penicillium simplicissimum: an alternative charge balancing ion flow in case of reduced proton backflow?

    PubMed

    Burgstaller, W; Zanella, A; Schinner, F

    1994-01-01

    Organic acids excreted by filamentous fungi may be used to win metals from industrial secondary raw materials. For a future commercial use a high production rate of organic acids is necessary. The conditions under which the commercially used fungus Aspergillus niger excretes high amounts of citric acid can not be maintained in metal leaching processes. However, Penicillium simplicissimum showed an enhanced citric acid efflux in the presence of an industrial filter dust containing 50% zinc oxide. Because Good buffers of high molarity were able to mimic the effect of zinc oxide, the high buffering capacity of zinc oxide and not an effect of the zinc ions was held responsible for the enhanced citric acid efflux. The presence of ammonium and trace elements reduced this buffer-stimulated citric acid efflux, whereas the plant hormone auxine canceled this reduction. This citric acid efflux was influenced by a depolarization of the membrane: the freely permeable compound tetraphenylphosphoniumbromide decreased the citric acid efflux, without decreasing intracellular citric acid or consumption of glucose and oxygen. Vanadate, an inhibitor of the plasma membrane H(+)-ATPase also reduced the buffer-stimulated citric acid efllux. The role of the efflux of citrate anions as an alternative charge balancing ion flow in case of impaired backflow of extruded protons because of a high extracellular buffering capacity is discussed.

  12. Transport of citrate-coated silver nanoparticles in unsaturated sand

    NASA Astrophysics Data System (ADS)

    Kumahor, Samuel; Hron, Pavel; Metreveli, George; Schaumann, Gabriele; Vogel, Hans-Jörg

    2015-04-01

    Chemical factors and physical constraints lead to coupled effects during particle transport in unsaturated porous media. Unlike for saturated transport, studies on unsaturated transport as typical for soil are currently scarce. We investigated the mobility of citrate-coated Ag NPs in unsaturated sand (grain diameter: 0.1-0.3 mm). For three flux rates and a given pore-water ionic strength (1 mM KNO3), the citrate-coated Ag NPs were less mobile at pH = 5 compared to pH = 9. The classic Derjaguin-Landau-Verwey-Overbeek (DLVO) theory suggests unfavorable deposition conditions at both, the air-water interface and solid-water interface. Breakthrough curves measured under quasi-steady state unsaturated flow showed retardation of the citrate-coated Ag NPs compared to inert solute (KBr). After flushing with nanoparticle-free 1 mM KNO3 solution (pH-adjusted), retention was much lower in deeper depths compared to the surface where the particles entered the flow field. The results show a non-linear dependence of nanoparticle (NP) mobility on flux rate and water content. Especially the observed retardation similar to equilibrium sorption is in contrast to observations under saturated flow conditions. A convection-dispersion and reaction model that combines a reversible equilibrium process and a non-equilibrium interaction process reproduced the measured breakthrough curves reasonably well. From comparison between saturated and unsaturated experiments we conclude that the air-water interface is responsible for the reversible equilibrium process while the water-solid interface accounts for irreversible soption.

  13. Antitumor effect and toxicity of free rhodium (II) citrate and rhodium (II) citrate-loaded maghemite nanoparticles in mice bearing breast cancer

    PubMed Central

    2013-01-01

    Background Magnetic fluids containing superparamagnetic iron oxide nanoparticles represent an attractive platform as nanocarriers in chemotherapy. Recently, we developed a formulation of maghemite nanoparticles coated with rhodium (II) citrate, which resulted in in vitro cytotoxicity enhanced up to 4.6 times when compared to free rhodium (II) citrate formulation on breast carcinoma cells. In this work, we evaluate the antitumor activity and toxicity induced by these formulations in Balb/c mice bearing orthotopic 4T1 breast carcinoma. Methods Mice were evaluated with regard to the treatments’ toxicity through analyses of hemogram, serum levels of alanine aminotransferase, iron, and creatinine; DNA fragmentation and cell cycle of bone marrow cells; and liver, kidney and lung histology. In addition, the antitumor activity of rhodium (II) citrate and maghemite nanoparticles coated with rhodium (II) citrate was verified by tumor volume reduction, histology and immunohistochemistry. Results Regarding the treatments’ toxicity, no experimental groups had alterations in levels of serum ALT or creatinine, and this suggestion was corroborated by the histopathologic examination of liver and kidney of mice. Moreover, DNA fragmentation frequency of bone marrow cells was lower than 15% in all experimental groups. On the other hand, the complexes rhodium (II) citrate-functionalized maghemite and free rhodium (II) citrate led to a marked growth inhibition of tumor and decrease in CD31 and Ki-67 staining. Conclusions In summary, we demonstrated that both rhodium (II) citrate and maghemite nanoparticles coated with rhodium (II) citrate formulations exhibited antitumor effects against 4T1 metastatic breast cancer cell line following intratumoral administration. This antitumor effect was followed by inhibition of both cell proliferation and microvascularization and by tumor tissue injury characterized as necrosis and fibrosis. Remarkably, this is the first published report

  14. The effect of EDDS and citrate on the uptake of lead in hydroponically grown Matthiola flavida.

    PubMed

    Mohtadi, Ahmad; Ghaderian, Seyed Majid; Schat, Henk

    2013-10-01

    Root and shoot lead concentrations and the impact of chelating agents on these were investigated in two populations of the novel metallophyte Matthiola flavida. Plants were exposed in hydroponics to Pb(NO3)2, supplied alone, or in combination with citric acid, or EDDS. When supplied at concentrations expected to bind about 95% of the Pb in a solution containing 1-μM Pb (1000 μM citrate or 3.1 μM EDDS, respectively), the root and shoot Pb concentrations were dramatically lowered, in comparison with a 1-μM free ionic Pb control exposure. A 1-mM EDDS+1-μM Pb treatment decreased the plants' Pb concentrations further, even to undetectable levels in one population. At 100 μM Pb in a 1-mM EDDS-amended solution the Pb concentration increased strongly in shoots, but barely in roots, in comparison with the 1-μM Pb+1-mM EDDS treatment, without causing toxicity symptoms. Further increments of the Pb concentration in the 1-mM EDDS-amended solution, i.e. to 800 and 990 μM, caused Pb hyperaccumulation, both in roots and in shoots, associated with a complete arrest of root growth and foliar necrosis. M. flavida seemed to be devoid of constitutive mechanisms for uptake of Pb-citrate or Pb-EDDS complexes. Hyperaccumulation of Pb-EDDS occurred only at high exposure levels. Pb-EDDS was toxic, but is much less so than free Pb. Free EDDS did not seem to be toxic at the concentrations tested.

  15. Citrate synthase proteins in extremophilic organisms: Studies within a structure-based model

    SciTech Connect

    Różycki, Bartosz Cieplak, Marek

    2014-12-21

    We study four citrate synthase homodimeric proteins within a structure-based coarse-grained model. Two of these proteins come from thermophilic bacteria, one from a cryophilic bacterium and one from a mesophilic organism; three are in the closed and two in the open conformations. Even though the proteins belong to the same fold, the model distinguishes the properties of these proteins in a way which is consistent with experiments. For instance, the thermophilic proteins are more stable thermodynamically than their mesophilic and cryophilic homologues, which we observe both in the magnitude of thermal fluctuations near the native state and in the kinetics of thermal unfolding. The level of stability correlates with the average coordination number for amino acid contacts and with the degree of structural compactness. The pattern of positional fluctuations along the sequence in the closed conformation is different than in the open conformation, including within the active site. The modes of correlated and anticorrelated movements of pairs of amino acids forming the active site are very different in the open and closed conformations. Taken together, our results show that the precise location of amino acid contacts in the native structure appears to be a critical element in explaining the similarities and differences in the thermodynamic properties, local flexibility, and collective motions of the different forms of the enzyme.

  16. Five percent dextrose maximizes dose delivery of Yttrium-90 resin microspheres and reduces rates of premature stasis compared to sterile water

    PubMed Central

    Koran, Mary Ellen; Stewart, Samantha; Baker, Jennifer C.; Lipnik, Andrew J.; Banovac, Fil; Omary, Reed A.; Brown, Daniel B.

    2016-01-01

    Resin Yttrium-90 (Y90) microspheres have historically been infused using sterile water (H2O). In 2013, recommendations expanded to allow delivery with 5% dextrose in water (D5W). In this retrospective study, we hypothesized that D5W would improve Y90 delivery with a lower incidence of stasis. We reviewed 190 resin Y90 infusions using H2O (n=137) or D5W (n=53). Y90 dosimetry was calculated using the body surface area method. Infusion was halted if intra-arterial stasis was fluoroscopically identified prior to clearing the vial. Differences between H2O and D5W groups were calculated for activity prescription, percentage of cases reaching stasis, and percentage delivery of prescribed activity using z- and t-test comparisons, with α=0.05. Thirty-one of 137 H2O infusions developed stasis compared to 2 of 53 with D5W (z=3.07, p=1.05E-03). D5W also had a significantly higher prescribed activity than H2O [28.2 millicuries (mCi) vs. 20.4 mCi, respectively; t=5.0, p=1.1E-6]. D5W had a higher delivery percentage of the prescribed dose compared to H2O (101.5 vs. 92.7%, respectively; t=3.8, p=1.92E-4). In conclusion, resin microsphere infusion utilizing D5W has a significantly lower rate of stasis than H2O and results in more complete dose delivery. D5W is preferable to H2O for resin microsphere infusion. PMID:28105342

  17. Inkjet printing of silver citrate conductive ink on PET substrate

    NASA Astrophysics Data System (ADS)

    Nie, Xiaolei; Wang, Hong; Zou, Jing

    2012-11-01

    Direct synthesis of silver conductive film on PET substrate by inkjet printing silver citrate conductive ink was presented in this paper. This kind of conductive ink contained silver citrate as silver precursor, 1,2-diaminopropane as complex agent dissolving the silver salt and methanol and isopropanol as a media adjusting the viscosity and surface tension. The formation of silver-amine complex reduced the decomposition temperature from 180 °C to 135 °C, thus the ink could be cured at relatively low temperature. The film reached the lowest resistivity of 17 μΩ cm after cured at 150 °C for 50 min, 3.1 μΩ cm at 230 °C and possessed high reflection and excellent adhesive property. Electrical conductivity, surface morphology and composition were investigated by four-point probe method, scanning electron microscope (SEM) and energy dispersive X-ray spectroscopy (EDS). It is demonstrated how the cured condition affects the silver film. Moreover, radio-frequency identification (RFID) antenna was fabricated by inkjet printing, which opens up routes for the flexible electronics fabrication.

  18. Formulation, Characterization and Physicochemical Evaluation of Potassium Citrate Effervescent Tablets

    PubMed Central

    Aslani, Abolfazl; Fattahi, Fatemeh

    2013-01-01

    Purpose: The aim of this study was to design and formulation of potassium citrate effervescent tablet for reduction of calcium oxalate and urate kidney stones in patients suffering from kidney stones. Methods: In this study, 13 formulations were prepared from potassium citrate and effervescent base in different concentration. The flowability of powders and granules was studied. Then effervescent tablets were prepared by direct compression, fusion and wet granulation methods. The prepared tablets were evaluated for hardness, friability, effervescent time, pH, content uniformity. To amend taste of formulations, different flavoring agents were used and then panel test was done by using Latin Square method by 30 volunteers. Results: Formulations obtained from direct compression and fusion methods had good flow but low hardness. Wet granulation improves flowability and other physicochemical properties such as acceptable hardness, effervescence time ≤3 minutes, pH<6, friability < 1%, water percentage < 0.5% and accurate content uniformity. In panel test, both of combination flavors; (orange - lemon) and (strawberry - raspberry) had good acceptability. Conclusion: The prepared tablets by wet granulation method using PVP solution had more tablet hardness. It is a reproducible process and suitable to produce granules that are compressed into effervescent tablets due to larger agglomerates. PMID:24312839

  19. Transcriptional regulation of Bacillus subtilis citrate synthase genes.

    PubMed

    Jin, S; Sonenshein, A L

    1994-08-01

    The Bacillus subtilis citrate synthase genes citA and citZ were repressed during early exponential growth phase in nutrient broth medium and were induced as cells reached the end of exponential phase. Both genes were also induced by treatment of cells with the drug decoyinine. After induction, the steady-state level of citZ mRNA was about five times higher than that of citA mRNA. At least some of the citZ transcripts read through into the isocitrate dehydrogenase (citC) gene. Transcription from an apparent promoter site located near the 3' end of the citZ gene also contributed to expression of citC. In minimal medium, citA transcription was about 6-fold lower when glucose was the sole carbon source than it was when succinate was the carbon source. Expression of the citZ gene was repressed 2-fold by glucose and 10-fold when glucose and glutamate were present simultaneously. This latter synergistic repression is similar to the effect of glucose and glutamate on steady-state citrate synthase enzyme activity. CitR, a protein of the LysR family, appeared to be a repressor of citA but not of citZ.

  20. Green synthesis of multi metal- citrate complexes and their characterization

    NASA Astrophysics Data System (ADS)

    Raju, Usha; Warkar, Sudhir G.; Kumar, Anil

    2017-04-01

    Four new multi metal-citrate complexes have been synthesized through green synthetic pathways. Their synthesis by hydrothermal route in the present research is decorated with features such as, a simple one pot synthesis, cost effectiveness, easy to scale up for commercial production, efficient synthesis conditions like mild temperature and shorter duration which further rules out the possibility of forming byproducts which may cause damage to the environment and being environmental benign as it eliminates the use and recovery of harmful organic solvents such as N, N- dimethyl formamide and N, N- diethyl formamide, used by the researchers in the past during the synthesis of similar metal- organic framework complexes. All four complexes are well defined crystalline materials with polynuclear multi metal-citrate framework having cubic crystal structure as indicated by their Powder X-ray Diffraction patterns. These complexes have been characterized by Fourier Transform Infrared Spectroscopy, Scanning Electron Microscopy, Energy Dispersive X-ray Spectroscopy, Thermogravimetric analysis and Powder XRD techniques.

  1. A sensitive liquid chromatography-electrospray ionization-mass spectrometry method for the simultaneous determination of pentoxyverine citrate and guaifenesin in human plasma---application to pharmacokinetic and bioequivalence studies.

    PubMed

    Wen, Jinhua; Zhang, Hong; Xia, Chunhua; Hu, Xiao; Xu, Wenwei; Cheng, Xiaohua; Gao, Jun; Xiong, Yuqing

    2010-04-01

    A sensitive and specific liquid chromatography-electrospray ionization-mass spectrometry method for the identification and quantification of pentoxyverine citrate and guaifenesin in human plasma has been developed. After extraction from plasma samples by ethyl acetate, the internal standard and analytes were separated by high-performance liquid chromatographic on a Shim-pack VP-ODS C(18) column (150 x 2.0 mm) using a mobile phase consisting of A (methanol) and B (0.4% glacial acetic acid and 4 mmol/L ammonium acetate) (A:B, 43 : 57). Analysis was performed on a Shimadzu LC/MS-2010A in selected ion monitoring mode with a positive electrospray ionization interface. The method was linear in the concentration range of 1.0-640.0 ng/mL for pentoxyverine citrate and 0.025-6.4 microg/mL for guaifenesin. The inter- and intra- precision were all within 12% and accuracy ranged from 85 to 115%.The lower limits of quantification were 1.0 ng/mL for pentoxyverine citrate and 25.0 ng/mL for guaifenesin. The extraction recovery was on average 81.95% for pentoxyverine citrate and 89.03% for guaifenesin. This is the first assay method reported for the simultaneous determination of pentoxyverine citrate and guaifenesin in plasma using one chromatographic run.

  2. 21 CFR 172.755 - Stearyl monoglyceridyl citrate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... Limitations Citric acid Monoglycerides of fatty acids Prepared by the glycerolysis of edible fats and oils or derived from fatty acids conforming with § 172.860. Stearyl alcohol Derived from fatty acids conforming... specifications: Acid number 40 to 52. Total citric acid 15 to 18 percent. Saponification number 215-255. (c)...

  3. 21 CFR 172.755 - Stearyl monoglyceridyl citrate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... Limitations Citric acid Monoglycerides of fatty acids Prepared by the glycerolysis of edible fats and oils or derived from fatty acids conforming with § 172.860. Stearyl alcohol Derived from fatty acids conforming... specifications: Acid number 40 to 52. Total citric acid 15 to 18 percent. Saponification number 215-255. (c)...

  4. A novel citrate selective electrode based on surfactant modified nano-clinoptilolite.

    PubMed

    Hasheminejad, Mahdieh; Nezamzadeh-Ejhieh, Alireza

    2015-04-01

    A citrate-selective sensor was prepared by modification of a PVC membrane with modified nano-clinoptilolite particles by hexadecyltrimethyl ammonium surfactant (SMZ). A Nernstian slope of 29.9 ± 0.2 mV per decade of citrate concentration was obtained over the concentration range of 5.0 × 10(-5)-5.0 × 10(-2) mol L(-1) of citrate. The electrode showed a fast response time (⩽ 10 s) and a detection limit of 1.3 × 10(-5) mol L(-1) of citrate. The linear range and detection limit were respectively changed to 1.0 × 10(-4)-5.0 × 10(-2) mol L(-1) and 1.0 × 10(-4) mol L(-1) of citrate when the micronized clinoptilolite particles were used.

  5. Struvite crystal growth inhibition by trisodium citrate and the formation of chemical complexes in growth solution

    NASA Astrophysics Data System (ADS)

    Prywer, Jolanta; Mielniczek-Brzóska, Ewa; Olszynski, Marcin

    2015-05-01

    Effect of trisodium citrate on the crystallization of struvite was studied. To evaluate such an effect an experiment of struvite growth from artificial urine was performed. The investigations are related to infectious urinary stones formation. The crystallization process was induced by the addition of aqueous ammonia solution to mimic the bacterial activity. The spectrophotometric results demonstrate that trisodium citrate increases induction time with respect to struvite formation and decreases the growth efficiency of struvite. The inhibitory effect of trisodium citrate on the nucleation and growth of struvite is explained in base of chemical speciation analysis. Such an analysis demonstrates that the inhibitory effect is related with the fact that trisodium citrate binds NH4 + and Mg2+ ions in the range of pH from 7 to 9.5 characteristic for struvite precipitation. The most important is the MgCit- complex whose concentration strongly depends on an increase in pH rather than on an increase in citrate concentrations.

  6. 3-Bromopyruvate antagonizes effects of lactate and pyruvate, synergizes with citrate and exerts novel anti-glioma effects.

    PubMed

    El Sayed, S M; El-Magd, R M Abou; Shishido, Y; Chung, S P; Diem, T H; Sakai, T; Watanabe, H; Kagami, S; Fukui, K

    2012-02-01

    Oxidative stress-energy depletion therapy using oxidative stress induced by D-amino acid oxidase (DAO) and energy depletion induced by 3-bromopyruvate (3BP) was reported recently (El Sayed et al., Cancer Gene Ther., 19, 1-18, 2012). Even in the presence of oxygen, cancer cells oxidize glucose preferentially to produce lactate (Warburg effect) which seems vital for cancer microenvironment and progression. 3BP is a closely related structure to lactate and pyruvate and may antagonize their effects as a novel mechanism of its action. Pyruvate exerted a potent H(2)O(2) scavenging effect to exogenous H(2)O(2), while lactate had no scavenging effect. 3BP induced H(2)O(2) production. Pyruvate protected against H(2)O(2)-induced C6 glioma cell death, 3BP-induced C6 glioma cell death but not against DAO/D-serine-induced cell death, while lactate had no protecting effect. Lactate and pyruvate protected against 3BP-induced C6 glioma cell death and energy depletion which were overcome with higher doses of 3BP. Lactate and pyruvate enhanced migratory power of C6 glioma which was blocked by 3BP. Pyruvate and lactate did not protect against C6 glioma cell death induced by other glycolytic inhibitors e.g. citrate (inhibitor of phosphofructokinase) and sodium fluoride (inhibitor of enolase). Serial doses of 3BP were synergistic with citrate in decreasing viability of C6 glioma cells and spheroids. Glycolysis subjected to double inhibition using 3BP with citrate depleted ATP, clonogenic power and migratory power of C6 glioma cells. 3BP induced a caspase-dependent cell death in C6 glioma. 3BP was powerful in decreasing viability of human glioblastoma multiforme cells (U373MG) and C6 glioma in a dose- and time-dependent manner.

  7. Oxidative modification of citrate synthase by peroxyl radicals and protection with novel antioxidants.

    PubMed

    Chepelev, Nikolai L; Bennitz, Joshua D; Wright, James S; Smith, Jeffrey C; Willmore, William G

    2009-12-01

    In mammals, aging is linked to a decline in the activity of citrate synthase (CS; E.C. 2.3.3.1), the first enzyme of the citric acid cycle. We used 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH), a water-soluble generator of peroxyl and alkoxyl radicals, to investigate the susceptibility of CS to oxidative damage. Treatment of isolated mitochondria with AAPH for 8-24 h led to CS inactivation; however, the activity of aconitase, a mitochondrial enzyme routinely used as an oxidative stress marker, was unaffected. In addition to enzyme inactivation, AAPH treatment of purified CS resulted in dityrosine formation, increased protein surface hydrophobicity, and loss of tryptophan fluorescence. Propyl gallate, 1,8-naphthalenediol, 2,3-naphthalenediol, ascorbic acid, glutathione, and oxaloacetate protected CS from AAPH-mediated inactivation, with IC(50) values of 9, 14, 34, 37, 150, and 160 muM, respectively. Surprisingly, the antioxidant epigallocatechin gallate offered no protection against AAPH, but instead caused CS inactivation. Our results suggest that the current practice of using the enzymatic activity of CS as an index of mitochondrial abundance and the use of aconitase activity as an oxidative stress marker may be inappropriate, especially in oxidative stress-related studies, during which alkyl peroxyl and alkoxyl radicals can be generated.

  8. [Contribution to the problem of preventing recurrences of oxalate and phosphate urinary caluli: active modification of citrate excretion and Ca++-binding capacity in the urine of Wistar rats].

    PubMed

    Leskovar, P; Hropot, M; Wellnhofer, E; Scherm, D; Schade, K L

    1982-03-01

    Citric acid may well be, quantitatively and in terms of complex chemistry, the most important of the organic acids capable of binding Ca++ in urine. Since the quantitative determination of citrates in urine became a routine method in many research-orientated urological laboratories thanks to the introduction of standardized enzymatic tests, reports of a reduced excretion of citrates in patients with (recurrent) (oxalate) calculi have become frequent. During our long-term study of patients with recurrent formation of calculi we also observed a clear deficit of citrates in their morning, midday and evening urine. The conspicuous incidence of calculi when there is a concurrence of hypocitraturia and alkaline urine (RTA, in animal experiments: acetazolamide) clearly suggests the lithoprotective significance of citric acid. By quantitatively testing a large number of organic compounds which are interesting both structurally and in terms of complex chemistry, it has been possible to find some substances which restrict crystallization, raise the level of citrates and bind Ca++. A few have also found to restrict the excretion of oxalate in Wistar rats.

  9. Heterotopic pregnancy following induction of ovulation with clomiphene citrate

    PubMed Central

    Ghandi, Sedigheh; Ahmadi, Raheleh; Fazel, Mahmoud

    2011-01-01

    Background: Although heterotopic gestation is common in assisted reproductive techniques, it is very rare in natural conception and clomiphene induced pregnancy. Diagnosis and appropriate intervention of heterotopic pregnancy requires a high index of suspicious. Case: In this paper a case of heterotopic pregnancy in a 30-year old woman with hemoperitoneum from ruptured tubal pregnancy with live intrauterine gestation at 9 weeks of gestation is reported. Conclusion: This case suggests that a heterotopic pregnancy must always be considered particularly after the induction of ovulation by clomiphene citrate or assisted reproductive technology. Every clinician treating women of reproductive age should keep this diagnosis in mind. It also demonstrates that early diagnosis is essential in order to salvage the intrauterine pregnancy and avoid maternal morbidity and mortality. PMID:26396583

  10. Response of patients with indolent systemic mastocytosis to tamoxifen citrate.

    PubMed

    Butterfield, Joseph H; Chen, Dong

    2016-01-01

    We examined whether tamoxifen citrate at 20mg/day for 1 year had a beneficial effect on laboratory findings, bone marrow mastocytosis, common clinical symptoms, or quality-of-life assessment for 5 women and 2 men with indolent systemic mastocytosis. Tamoxifen was well tolerated. We found significant reductions in the platelet count, serum alkaline phosphatase, and 24-h urinary excretion of N-methylhistamine and significant increases in serum lactate dehydrogenase and (excluding 2 patients taking aspirin) in 24-h urinary excretion of 11β-prostaglandin F2α. Overall, no change occurred in percent involvement of bone marrow by mastocytosis. Symptom scores were mild and did not change during the treatment. The 36-Item Short Form Health Survey scores for quality of life physical and mental components showed no marked changes. Tamoxifen, an older, nonhematotoxic medication, has limited activity in systemic mastocytosis at the dosage used in this study.

  11. Sildenafil citrate for the treatment of pulmonary hypertension.

    PubMed

    Hrometz, Sandra L; Shields, Kelly M

    2006-12-01

    Pulmonary arterial hypertension is a progressive disease that has a high rate of mortality. For these reasons, early treatment is essential. Treatment choices for pulmonary arterial hypertension are limited by drug tolerability, drug cost and inconvenience associated with administration techniques and dosing schedules. Therefore, a therapy that provides oral dosing with limited side effects would prove useful in managing many patients. Sildenafil citrate, the first and highly publicized oral medication to receive approval from the U.S. Food and Drug Administration for erectile dysfunction, has recently been approved for treatment of pulmonary arterial hypertension. This review summarizes the normal physiology of the pulmonary vasculature, and the pathophysiology involved in pulmonary arterial hypertension and the role of sildenafil in its treatment.

  12. Identification of ATP Citrate Lyase as a Positive Regulator of Glycolytic Function in Glioblastomas

    PubMed Central

    Beckner, Marie E.; Fellows-Mayle, Wendy; Zhang, Zhe; Agostino, Naomi R.; Kant, Jeffrey A.; Day, Billy W.; Pollack, Ian F.

    2009-01-01

    Glioblastomas, the most malignant type of glioma, are more glycolytic than normal brain tissue. Robust migration of glioblastoma cells has been previously demonstrated under glycolytic conditions and their pseudopodia contain increased glycolytic and decreased mitochondrial enzymes. Glycolysis is suppressed by metabolic acids, including citric acid which is excluded from mitochondria during hypoxia. We postulated that glioma cells maintain glycolysis by regulating metabolic acids, especially in their pseudopodia. The enzyme that breaks down cytosolic citric acid is ATP citrate lyase (ACLY). Our identification of increased ACLY in pseudopodia of U87 glioblastoma cells on 1D gels and immunoblots prompted investigation of ACLY gene expression in gliomas for survival data and correlation with expression of ENO1, that encodes enolase 1. Queries of the NIH’s REMBRANDT brain tumor database based on Affymetrix data indicated that decreased survival correlated with increased gene expression of ACLY in gliomas. Queries of gliomas and glioblastomas found an association of upregulated ACLY and ENO1 expression by chi square for all probe sets (reporters) combined and correlation for numbers of probe sets indicating shared upregulation of these genes. Real-time quantitative PCR confirmed correlation between ACLY and ENO1 in 21 glioblastomas (p < 0.001). Inhibition of ACLY with hydroxycitrate suppressed (p < 0.05) in vitro glioblastoma cell migration, clonogenicity and brain invasion under glycolytic conditions and enhanced the suppressive effects of a Met inhibitor on cell migration. In summary, gene expression data, proteomics and functional assays support ACLY as a positive regulator of glycolysis in glioblastomas. PMID:19795461

  13. Recessive mutations in SLC13A5 result in a loss of citrate transport and cause neonatal epilepsy, developmental delay and teeth hypoplasia.

    PubMed

    Hardies, Katia; de Kovel, Carolien G F; Weckhuysen, Sarah; Asselbergh, Bob; Geuens, Thomas; Deconinck, Tine; Azmi, Abdelkrim; May, Patrick; Brilstra, Eva; Becker, Felicitas; Barisic, Nina; Craiu, Dana; Braun, Kees P J; Lal, Dennis; Thiele, Holger; Schubert, Julian; Weber, Yvonne; van 't Slot, Ruben; Nürnberg, Peter; Balling, Rudi; Timmerman, Vincent; Lerche, Holger; Maudsley, Stuart; Helbig, Ingo; Suls, Arvid; Koeleman, Bobby P C; De Jonghe, Peter

    2015-11-01

    The epileptic encephalopathies are a clinically and aetiologically heterogeneous subgroup of epilepsy syndromes. Most epileptic encephalopathies have a genetic cause and patients are often found to carry a heterozygous de novo mutation in one of the genes associated with the disease entity. Occasionally recessive mutations are identified: a recent publication described a distinct neonatal epileptic encephalopathy (MIM 615905) caused by autosomal recessive mutations in the SLC13A5 gene. Here, we report eight additional patients belonging to four different families with autosomal recessive mutations in SLC13A5. SLC13A5 encodes a high affinity sodium-dependent citrate transporter, which is expressed in the brain. Neurons are considered incapable of de novo synthesis of tricarboxylic acid cycle intermediates; therefore they rely on the uptake of intermediates, such as citrate, to maintain their energy status and neurotransmitter production. The effect of all seven identified mutations (two premature stops and five amino acid substitutions) was studied in vitro, using immunocytochemistry, selective western blot and mass spectrometry. We hereby demonstrate that cells expressing mutant sodium-dependent citrate transporter have a complete loss of citrate uptake due to various cellular loss-of-function mechanisms. In addition, we provide independent proof of the involvement of autosomal recessive SLC13A5 mutations in the development of neonatal epileptic encephalopathies, and highlight teeth hypoplasia as a possible indicator for SLC13A5 screening. All three patients who tried the ketogenic diet responded well to this treatment, and future studies will allow us to ascertain whether this is a recurrent feature in this severe disorder.

  14. Citrate anticoagulation during plasma exchange in a patient with thrombotic thrombocytopenic purpura: short heparin-free hemodialysis helps to attenuate citrate load.

    PubMed

    Buturović-Ponikvar, Jadranka; Pernat, Andreja Marn; Ponikvar, Rafael

    2005-06-01

    The treatment of thrombotic thrombocytopenic purpura requires plasma exchange using fresh frozen plasma as a replacement solution once or even twice daily. If citrate anticoagulation is needed, the citrate load (both from fresh frozen plasma and citrate as an anticoagulant) can be significant, causing metabolic complications. The aim of our report is to present our experience with citrate anticoagulation in a patient with thrombotic thrombocytopenic purpura treated with daily membrane plasma exchange. Twenty-six plasma exchange procedures were performed during 20 days of treatment in a 46-year-old female. The blood flow was 98 +/- 8 mL/min; 4% trisodium citrate was infused into the arterial line (134 +/- 11 mL/h) and 1 M CaCl2 into the venous line (11.4 +/- 1.8 mL/h). Fresh frozen plasma (first 7 procedures) or cryo-poor plasma (19 procedures) were used as a replacement solution, 3176 +/- 536 mL per procedure. A total of 88,930 mL of plasma was exchanged. No serious side-effects occurred. iCa before plasma exchange was significantly higher than afterwards (1.23 +/- 0.12 vs. 1.12 +/- 0.12, P = 0.0047). Significant alkalosis occurred after three plasma exchanges (pH 7.64, bicarbonate 36.2 mmol/L), and was corrected by 3-h heparin-free hemodialysis with dialysate as follows: K 4.0 mmol/L, calcium 1.5 mmol/L, and bicarbonate set to 24 mmol/L. After dialysis, pH was 7.45 and bicarbonate 29.4 mmol/L. Another (2-h) heparin-free hemodialysis procedure was repeated after six plasma exchanges. Citrate anticoagulation can be safely performed in patients treated with plasma exchange once or twice daily. Periodically performed short heparin-free hemodialysis can correct metabolic alkalosis and attenuate the citrate load.

  15. Circulating concentrations of non-esterified fatty acids (NEFA) as mediators of the innate immune response in cattle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We previously reported that temperamental cattle have greater non-esterified fatty acid (NEFA) concentrations and an altered innate immune response compared to calm cattle. Therefore, this trial was designed to determine if increasing energy availability via a lipid infusion or bolus dextrose inject...

  16. The Citrate Carrier CitS Probed by Single-Molecule Fluorescence Spectroscopy

    PubMed Central

    Kästner, Christopher N.; Prummer, Michael; Sick, Beate; Renn, Alois; Wild, Urs P.; Dimroth, Peter

    2003-01-01

    A prominent region of the Na+-dependent citrate carrier (CitS) from Klebsiella pneumoniae is the highly conserved loop X-XI, which contains a putative citrate binding site. To monitor potential conformational changes within this region by single-molecule fluorescence spectroscopy, the target cysteines C398 and C414 of the single-Cys mutants (CitS-sC398, CitS-sC414) were selectively labeled with the thiol-reactive fluorophores AlexaFluor 546/568 C5 maleimide (AF546, AF568). While both single-cysteine mutants were catalytically active citrate carriers, labeling with the fluorophore was only tolerated at C398. Upon citrate addition to the functional protein fluorophore conjugate CitS-sC398-AF546, complete fluorescence quenching of the majority of molecules was observed, indicating a citrate-induced conformational change of the fluorophore-containing domain of CitS. This quenching was specific for the physiological substrate citrate and therefore most likely reflecting a conformational change in the citrate transport mechanism. Single-molecule studies with dual-labeled CitS-sC398-AF546/568 and dual-color detection provided strong evidence for a homodimeric association of CitS. PMID:12609868

  17. Effect of volume expansion on renal citrate and ammonia metabolism in KCl-deficient rats.

    PubMed Central

    Adler, S; Zett, B; Anderson, B; Fraley, D S

    1975-01-01

    When rats with desoxycorticosterone acetate (DOCA)-induced potassium chloride deficiency are given sodium chloride there is simultaneously a partial correction of metabolic alkalosis and a marked reduction in urinary citrate excretion and renal citrate content. To examine DOCA's role in this phenomenon and to determine how sodium chloride alters renal metabolism, rats were made KC1 deficient using furosemide and a KC1-deficient diet. Renal citrate and ammonia metabolism were then studied after chronic oral sodium chloride administration or acute volume expansion with isotonic mannitol. Although both maneuvers partially corrected metabolic alkalosis, sodium chloride raised serum chloride concentration while mannitol significantly decreased it. Urinary citrate excretion decreased to 10% of control in rats given NaCl and to 50% of control in rats infused with mannitol. The filtered load of citrate was constant or increased indicating increased tubular citrate reabsorption. Renal cortical citrate content also decreased approximately 50%. Renal cortical slices from KCl-deficient rats incubated in low or normal chloride media produced equal amounts of 14CO2 from (1, 5-14C) citrate. In addition, urinary ammonia excretion increased by over 300% in both groups. This occurred in the mannitol group despite increased urinary pH and flow rate indicating a rise in renal ammonia production. It seems that neither DOCA nor an increase in serum chloride concentration explains the experimental results. Rather, it appears that volume expansion is responsible for increased renal tubular citrate reabsorption and renal ammonia production. As these renal metabolic responses ordinarily occur in response to acidosis, the data are consistent with the hypothesis that volume expansion reduces renal cell pH in 3KCl-deficient rats. PMID:239022

  18. Chemical Speciation Analysis of Sports Drinks by Acid-Base Titrimetry and Ion Chromatography: A Challenging Beverage Formulation Project

    ERIC Educational Resources Information Center

    Drossman, Howard

    2007-01-01

    Students have standardized a sodium hydroxide solution and analyzed commercially available sports drinks by titrimetric analysis of the triprotic citric acid, dihydrogen phosphate, and dihydrogen citrate and by ion chromatography for chloride, total phosphate and citrate. These experiments are interesting examples of analyzing real-world food and…

  19. Investigation the efficacy of intra-articular prolotherapy with erythropoietin and dextrose and intra-articular pulsed radiofrequency on pain level reduction and range of motion improvement in primary osteoarthritis of knee

    PubMed Central

    Rahimzadeh, Poupak; Imani, Farnad; Faiz, Seyed Hamid Reza; Entezary, Saeed Reza; Nasiri, Ali Akbar; Ziaeefard, Mohsen

    2014-01-01

    Background: Osteoarthritis is one of the most common diseases and the knee is the most commonly affected joint. Intra-articular prolotherapy is being utilized in acute and chronic pain management setting. This study was designed to compare the efficacy of three methods of intra-articular knee joint therapies with erythropoietin, dextrose, and pulsed radiofrequency. Materials and Methods: After approval by the Ethics Committee and explaining the therapeutic method to volunteers, 70 patients who were suffering from primary knee osteoarthrosis went through one of the treatment methods (erythropoietin, dextrose, and pulsed radiofrequency). The study was double-blind randomized clinical trial performed from December 2012 to July 2013. Patients’ pain level was assessed through the visual analog pain scale (VAS), and range of motion (ROM) was measured by goniometric method. Furthermore, patients’ satisfaction was assessed before and after different treatment methods in weeks 2, 4, and 12. For analysis, Chi-square, one-way ANOVA, and repeated measured ANOVA were utilized. Results: The demographic results among the three groups did not indicate any statistical difference. The mean VAS in erythropoietin group in the 2nd, 4th, and 12th weeks was 3.15 ± 1.08, 3.15 ± 1.08, and 3.5 ± 1.23, respectively (P ≤ 0.005). Knee joint ROM in the erythropoietin group in the 2nd, 4th, and 12th weeks was 124 ± 1.50, 124 ± 1.4, and 123 ± 1.53 respectively (P ≤ 0.005). Satisfaction score in the 12th week in erythropoietin group was extremely satisfied 15%, satisfied 55%, and moderately satisfied 30%, (P = 0.005). No specific side-effects were observed. Conclusion: Intra-articular prolotherapy with erythropoietin was more effective in terms of pain level reduction and ROM improvement compared with dextrose and pulsed radiofrequency. PMID:25422652

  20. Purification of L-glutamate-dependent citrate lyase from Clostridium sphenoides and electron microscopic analysis of citrate lyase isolated from Rhodopseudomonas gelatinosa, Streptococcus diacetilactis and C. sphenoides.

    PubMed

    Antranikian, G; Klinner, C; Kümmel, A; Schwanitz, D; Zimmermann, T; Mayer, F; Gottschalk, G

    1982-08-01

    Citrate lyase from Clostridium sphenoides was purified 72-fold with a yield of 11%. In contrast to citrate lyase from other sources the activity of this enzyme was strictly dependent on the presence of L-glutamate. The purified enzyme was only stable in the presence of 150 mM L-glutamate or 7 mM L-glutamate plus glycerol, sucrose or bovine serum albumin. Changes of the L-glutamate pool and of enzyme activity in growing cells of C. sphenoides indicated that citrate lyase activity in this organism was regulated by the intracellular L-glutamate concentration. Citrate lyase isolated from C. sphenoides, Rhodopseudomonas gelatinosa and Streptococcus diacetilactis was investigated by electron microscopy using the negative staining technique. Three different projections of enzyme molecules were observed: 'star' form, 'ring' form and 'triangle' form. In samples from R. gelatinosa and S. diacetilactis, star and ring forms occurred in a ratio of about 1:9. Using the enzyme from S. diacetilactis it was demonstrated that this ratio could be altered in favour of the star form by the addition of citrate or tricarballylate. The triangle form was observed in less than 1% of all evaluated molecules and may represent a transition form. In lyase samples from C. sphenoides there existed a correlation between enzyme activity and the proportion of stars and rings at varying concentrations of L-glutamate.

  1. Citrate Attenuates Adenine-Induced Chronic Renal Failure in Rats by Modulating the Th17/Treg Cell Balance.

    PubMed

    Ou, Yan; Li, Shuiqin; Zhu, Xiaojing; Gui, Baosong; Yao, Ganglian; Ma, Liqun; Zhu, Dan; Fu, Rongguo; Ge, Heng; Wang, Li; Jia, Lining; Tian, Lifang; Duan, Zhaoyang

    2016-02-01

    Citrate is commonly used as an anticoagulant in hemodialysis for chronic renal failure (CRF) and for the regulation of the immune dysfunction in CRF patients. The objective of this study was to investigate the effect of citrate on the balance of T helper 17 (Th17) and regulatory T (Treg) cells in CRF. The levels of blood urea nitrogen (BUN) and serum creatinine (Scr) were significantly increased in the CRF model group compared to the control group, and were decreased in the citrate-treated groups. Citrate treatment inhibited the viability of Th17 cells while elevating the viability of Treg cells in CRF rats. Moreover, Th17-related cytokines significantly decreased while the Treg-related cytokines significantly increased with citrate treatment. Moreover, citrate had a negative influence on the deviation of Th17/Treg cells in CRF rats. Therefore, our study suggests that citrate had an anti-inflammatory effect on CRF through the modulation of the Th17/Treg balance.

  2. 21 CFR 172.755 - Stearyl monoglyceridyl citrate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... Limitations Citric acid Monoglycerides of fatty acids Prepared by the glycerolysis of edible fats and oils or derived from fatty acids conforming with § 172.860. Stearyl alcohol Derived from fatty acids conforming... additive is used or intended for use as an emulsion stabilizer in or with shortenings...

  3. Physicochemical and Microbiological Stability of the Extemporaneous Sildenafil Citrate Oral Suspension.

    PubMed

    Sae Yoon, Attawadee; Sawatdee, Somchai; Woradechakul, Chuthamas; Sae Chee, Kridsada; Atipairin, Apichart

    2015-01-01

    Sildenafil is a potent and selective phosphodiesterase-5 inhibitor that is effectively used in the treatment of pulmonary arterial hypertension. In several countries, hospital pharmacists prepare the drug in an extemporaneous liquid preparation as there are no liquid formulations available for pediatric and adult uses. The purpose of this study was to evaluate the stability of an extemporaneous sildenafil citrate oral suspension for 90 days, according to the ASEAN guideline on stability studies of drug products. The results showed that the preparation was a white suspension with a sweet taste. It was a viscous and weakly acidic mixture with pseudoplastic behavior. The drug content was in the range between 99.23% and 102.23%, and the microbial examination met the general requirements throughout the study period. Therefore, the extemporaneously compounded sildenafil suspensions were physically, chemically, and microbiologically stable for at least 90 days when stored at 30° and 40°C. Furthermore, the in-use stability study showed that the preparations had acceptable attributes at least 14 days after the first-time use. This might provide an alternative option when the commercial suspension is unavailable.

  4. Nanoscale zero-valent iron for the removal of Zn2+, Zn(II)-EDTA and Zn(II)-citrate from aqueous solutions.

    PubMed

    Kržišnik, Nina; Mladenovič, Ana; Škapin, Andrijana Sever; Škrlep, Luka; Ščančar, Janez; Milačič, Radmila

    2014-04-01

    The parameters which influence the removal of different zinc (Zn) species: Zn(2+), Zn(II)-EDTA and Zn(II)-citrate from aqueous solutions by nanoparticles of zero-valent iron (nZVI) were investigated at environmental relevant pH values. Untreated, surface modified and silica-fume supported nZVI were applied at different iron loads and contact times to Zn solutions, which were buffered to pH 5.3, 6.0 and 7.0. The results revealed that pH, the type of nZVI, the iron load, the contact time, and the Zn species all had a significant influence on the efficiency of removal. Zn(2+), Zn(II)-EDTA and Zn(II)-citrate were the most effectively removed from aqueous solutions by untreated nZVI. Zn(2+) removal was governed mainly by adsorption onto precipitated iron oxides. Complete removal of Zn(2+) and Zn(II)-citrate was obtained at all pH values investigated. The removal of strong Zn(II)-EDTA complex was successful only at acidic pH, which favored degradation of Zn(II)-EDTA. Consequently, the released Zn(2+) was completely removed from the solution by adsorption onto iron oxides.

  5. Inhibition of flower formation by antisense repression of mitochondrial citrate synthase in transgenic potato plants leads to a specific disintegration of the ovary tissues of flowers.

    PubMed Central

    Landschütze, V; Willmitzer, L; Müller-Röber, B

    1995-01-01

    The tricarboxylic acid (TCA) cycle constitutes a major component of the mitochondrial metabolism of eucaryotes, including higher plants. To analyze the importance of this pathway, we down-regulated mitochondrial citrate synthase (mCS; EC 4.1.3.7), the first enzyme of the TCA cycle, in transgenic potato plants using an antisense RNA approach. Several transformants were identified with reduced citrate synthase activity (down to approximately 6% of wild-type activity). These plants were indistinguishable from wild-type plants in the greenhouse during vegetative growth. A major change, however, was seen upon initiation of the generative phase (flower formation). In the case of transgenic plants with a strong reduction in citrate synthase activity (< 30% of wild-type levels), flower buds formed > 2 weeks later as compared with wild-type plants. Furthermore, flower buds from these plants did not develop into mature flowers but rather were aborted at an early stage of development. Microscopic analysis showed that in these cases ovaries disintegrated during flower development. We conclude that the TCA cycle is of major importance during the transition from the vegetative to the generative phase. Images PMID:7882969

  6. 75 FR 34360 - Listing of Color Additives Exempt From Certification; Bismuth Citrate; Confirmation of Effective...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-17

    ... level of bismuth citrate as a color additive in cosmetics intended for coloring hair on the scalp. DATES... hair on the scalp. FDA gave interested persons until April 26, 2010, to file objections or requests...

  7. Pharmacokinetics of bismuth and ranitidine following single doses of ranitidine bismuth citrate

    PubMed Central

    KOCH, K M; DAVIS, I M; GOODING, A E; YIN, Y

    1996-01-01

    The pharmacokinetics of bismuth and ranitidine derived from ranitidine bismuth citrate given in single oral doses ranging from 200 mg to 1600 mg were evaluated in healthy subjects. Bismuth was only minimally absorbed (<0.5% of the amount dosed) after administration of ranitidine bismuth citrate, and peak plasma concentrations never exceeded 33 ng ml−1 in any subject. Plasma concentrations and urinary recoveries of bismuth at doses up to and including 800 mg were relatively constant and not proportional to dose. Bismuth absorption was increased more than proportionally with the dose at 1600 mg. The pharmacokinetics of ranitidine after administration of ranitidine bismuth citrate were dose-proportional and consistent with previous observations for ranitidine administered alone. Ranitidine bismuth citrate was well-tolerated in single oral doses of up to 1600 mg. PMID:8864318

  8. 21 CFR 520.763c - Dithiazanine iodide and piperazine citrate suspension.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... piperazine citrate). (b) Sponsor. See 054628 in § 510.600(c) of this chapter. (c) (d) Conditions of use—(1... for administration by stomach tube, it shall be labeled: “Federal law restricts this drug to use by...

  9. Preventing serpin aggregation: The molecular mechanism of citrate action upon antitrypsin unfolding

    SciTech Connect

    Pearce, Mary C.; Morton, Craig J.; Feil, Susanne C.; Hansen, Guido; Adams, Julian J.; Parker, Michael W.; Bottomley, Stephen P.

    2008-11-21

    The aggregation of antitrypsin into polymers is one of the causes of neonatal hepatitis, cirrhosis, and emphysema. A similar reaction resulting in disease can occur in other human serpins, and collectively they are known as the serpinopathies. One possible therapeutic strategy involves inhibiting the conformational changes involved in antitrypsin aggregation. The citrate ion has previously been shown to prevent antitrypsin aggregation and maintain the protein in an active conformation; its mechanism of action, however, is unknown. Here we demonstrate that the citrate ion prevents the initial misfolding of the native state to a polymerogenic intermediate in a concentration-dependent manner. Furthermore, we have solved the crystal structure of citrate bound to antitrypsin and show that a single citrate molecule binds in a pocket between the A and B beta-sheets, a region known to be important in maintaining antitrypsin stability.

  10. Kinetic studies of the regulation of mitochondrial malate dehydrogenase by citrate.

    PubMed Central

    Gelpí, J L; Dordal, A; Montserrat, J; Mazo, A; Cortés, A

    1992-01-01

    Mitochondrial malate dehydrogenase shows a complex regulation pattern in the presence of citrate. Previously published results indicate that this enzyme is activated by citrate in the NAD(+)----NADH direction and inhibited in the opposite direction. Moreover, high concentrations of L-malate or oxaloacetate produce deviations from the Michaelis-Menten behaviour. Results reported in this paper clearly show that citrate both activates and inhibits mitochondrial malate dehydrogenase in the same direction (NAD(+)----NADH), and in the same reaction medium, depending on substrate concentration. This surprising effect has made it necessary to propose a new kinetic mechanism that extends those previously suggested and allows us to explain both the citrate effect (activating or inhibitory) and the effect of high concentrations of L-malate and oxaloacetate. PMID:1567375

  11. Closed circuit recovery of copper, lead and iron from electronic waste with citrate solutions.

    PubMed

    Torres, Robinson; Lapidus, Gretchen T

    2017-02-01

    An integral closed circuit hydrometallurgical process is presented for base metal recovery from electronic waste. The leaching medium consists of a sodium citrate solution, from which base metals are retrieved by direct electrowinning, and the barren solution is recycled back to the leaching stage. This leaching-electrowinning cycle was repeated four times. The redox properties of the fresh citrate solution, as well as the leach liquors, were characterized by cyclic voltammetry to determine adequate conditions for metal reduction, as well as to limit citrate degradation. The leaching efficiency of electronic waste, employing the same solution after four complete cycles was 71, 83 and 94% for copper, iron and lead, respectively, compared to the original leach with fresh citrate solution.

  12. The role of citrate and phthalate during Co(II) coprecipitation with calcite

    NASA Astrophysics Data System (ADS)

    Lee, Young J.; Reeder, Richard J.

    2006-05-01

    The influence of citrate and phthalate on Co coprecipitation with calcite was investigated using a combination of batch experiments, Fourier-transform infra-red (FT-IR) spectroscopy, and thermogravimetric analysis (TGA) over a wide range of precipitation rates. Steady-state growth conditions (at constant [Ca], [Co], DIC, and pH) were generally achieved within 3-5 h, after which Co(II) partitioning into calcite was evaluated. Only minor differences are observed in the partition coefficient ( Kd) trends with and without citrate and phthalate as a function of calcite precipitation rate except at very low rates. Slight inhibition of calcite growth is observed in the presence of citrate or phthalate, which can be attributed to adsorption at surface sites. TGA curves for samples coprecipitated with citrate show a significant mass loss between 375 and 550 °C, whereas the weight-loss curves for the Co-phthalate coprecipitates are indistinguishable from those of the organic-free Co coprecipitates. This indicates that citrate is incorporated into calcite during calcite crystallization, whereas phthalate is excluded. FT-IR spectra for the sample with citrate show a broad absorption in the range 3700-3100 cm -1, which is attributable to water molecules coordinated to citrate coprecipitated with calcite. The preferential incorporation of citrate over phthalate likely reflects differences in both aqueous speciation and conformation of the carboxylate groups. This new finding may provide new insight to the factors that control the behavior of macromolecules and their incorporation into the structure of calcium carbonate during biomineralization.

  13. Anaerobic regulation of citrate fermentation by CitAB in Escherichia coli.

    PubMed

    Yamamoto, Kaneyoshi; Matsumoto, Fumika; Oshima, Taku; Fujita, Nobuyuki; Ogasawara, Naotake; Ishihama, Akira

    2008-11-01

    In Escherichia coli, CitB, a cognate response regulator of CitA, specifically bound to the promoter regions for mdh, citA, citC, and exuT. Transcription of these genes was induced by citrate under anaerobic conditions in a CitAB-dependent manner. Taking this together, we conclude that CitAB is the master regulatory system that activates the set of genes involved in citrate fermentation in E. coli.

  14. Clomiphene citrate treatment for late onset hypogonadism: rise and fall

    PubMed Central

    Marconi, Marcelo; Souper, Renato; Hartmann, Jonathan; Alvarez, Matías; Fuentes, Ignacio; Guarda, Francisco J.

    2016-01-01

    ABSTRACT Objective: Previous series have demonstrated that Clomiphene Citrate (CC) is an effective treatment to increase Total Testosterone (TT) in Late Onset Hypogonadism (LOH) patients. However, what happens to TT levels after ending CC treatment is still debatable. The objective of this study is to evaluate TT levels 3 months after the discontinuation of CC in patients with LOH who were previously successfully treated with the same drug. Materials and Methods: Twenty-seven patients with LOH that were successfully treated (achieved TT levels >11nmol/l) with CC 50mgs daily for 50 days were prospectively recruited in our Andrological outpatient clinic. CC was then stopped for 3 months and TT levels were measured at the end of this period. Results: Mean TT level before discontinuation of CC was 22.7±8.1nmol/L (mean±SD). Three months after discontinuation, mean TT level significantly decreased in all patients, 10.2±3.9nmol/l (p<0.01). Twenty-one patients (78%) decreased TT levels under 11nmol/L. Six patients (22%) had TT levels that remained within the normal recommended range (≥11nmol/l). No statistical significant differences were observed between both groups. Conclusion: In the short term LOH does not seem to be a reversible condition in most patients after CC treatment. More studies with longer follow-up are needed to evaluate the kinetics of TT in LOH. PMID:27622282

  15. Pseudohypernatremia secondary to trisodium citrate (Citra-LockTM)

    PubMed Central

    Milliere, Janice; Corriveau, Daryl; Parmar, Malvinder S.

    2016-01-01

    Introduction Hypernatremia is common among hospitalized patients especially in the intensive care units and presents an independent risk factor for mortality. Mild hypernatremia is often asymptomatic but severe hypernatremia causes central nervous system dysfunction with initial non-specific symptoms of encephalopathy that may progress to seizures, coma and death, if left untreated. Severe hypernatremia is a medical emergency and requires emergent medical attention. Materials and methods A haemodialysis patient who arrived for his scheduled haemodialysis treatment had monthly blood work drawn and was reported to have severe hypernatremia with serum sodium concentration of 183 mmol/L. The possibility of technique or laboratory error was considered and systematically evaluated. Results The serum sodium measurement using another analyser showed similar value of 182 mmolL. A repeat serum sodium level on a sample drawn 2 h later showed normal value of 139–140 mmol/L. A step-wise evaluation of the complete procedure from blood collection to analysis of the sample revealed this to be spuriously elevated serum sodium concentration secondary to contamination of the sample during sample collection with trisodium citrate, a catheter-lock solution, commonly used in dialysis units to maintain patency of dialysis catheters. Conclusions Spuriously elevated plasma sodium concentration (pseudohypernatremia) of mild degree is common but severe pseudohypernatremia is rare and the possibility of sample contaminations or laboratory error should be considered. Vigilance is required by both the medical and the laboratory staff to resolve such issues in a timely fashion to avoid unintended consequences. PMID:27346973

  16. Improved crystallinity, spatial arrangement and monodispersity of submicron La0.7Ba0.3MnO3 powders: A citrate chelation approach

    NASA Astrophysics Data System (ADS)

    Rao, Ch. N.; Samatham, S. Shanmukharao; Ganesan, V.; Sathe, V. G.; Phase, D. M.; Kale, S. N.

    2012-11-01

    The perovskite manganite systems have been the materials of tremendous interest due to their strong correlation between structure, transport and magnetism. These materials in their single-crystal form show colossal magneto-resistance (CMR), but the applied fields are very high (˜1-5 T). The polycrystalline samples do show high low-field magneto-resistance (LFMR), but good amount of control over particle sizes and grain-boundary distribution is required, which is well known but less realized in practical approaches. In this context, we report on synthesis and manipulation of polycrystalline La0.7Ba0.3MnO3 (LBMO) submicron powders using citric acid chelation. The Citrate-gel route is used to synthesize poly-dispersed LBMO powders which are subjected to citrate chelation for a duration of 0 (LB0) to 4 h(LB4) . The samples show improved ordering in X-ray diffraction patterns. Raman spectroscopy scans indicate changed mode signatures due to the probable chelating process, which alters the surface morphology. X-ray photoelectron microscopy shows an evidence of fine citrate layer on the grain boundaries. Low temperature B-H curves exhibit fine hysteresis loops for all samples, while room temperature B-H curves shows paramagnetic response. Scanning electron microscopy images showed the formation of well arranged, connected, mono-dispersed grains of LB4 sample, as against polydispered LB0. The magneto-resistance (at H=100 kOe) is seen to enhance for LB4 at its transition temperature (75%, as compared to LB0, where it is 60%), which can be attributed to the well-controlled inter-grain tunneling phenomenon and thin insulating regions in between, created due to citrate chelation, which probably enhances the scattering phenomenon and its susceptibility to applied fields. As citric acid is known to chelate Mn ions, it probably chelates the smaller LB particulate structure and leaves behind citrate-connected submicron grains of LBMO, which are seen to be well engineered.

  17. Mild reductions in mitochondrial citrate synthase activity result in a compromised nitrate assimilation and reduced leaf pigmentation but have no effect on photosynthetic performance or growth.

    PubMed

    Sienkiewicz-Porzucek, Agata; Nunes-Nesi, Adriano; Sulpice, Ronan; Lisec, Jan; Centeno, Danilo C; Carillo, Petronia; Leisse, Andrea; Urbanczyk-Wochniak, Ewa; Fernie, Alisdair R

    2008-05-01

    Transgenic tomato (Solanum lycopersicum) plants, expressing a fragment of the mitochondrial citrate synthase gene in the antisense orientation and exhibiting mild reductions in the total cellular activity of this enzyme, displayed essentially no visible phenotypic alteration from the wild type. A more detailed physiological characterization, however, revealed that although these plants were characterized by relatively few changes in photosynthetic parameters they displayed a decreased relative flux through the tricarboxylic acid cycle and an increased rate of respiration. Furthermore, biochemical analyses revealed that the transformants exhibited considerably altered metabolism, being characterized by slight decreases in the levels of organic acids of the tricarboxylic acid cycle, photosynthetic pigments, and in a single line in protein content but increases in the levels of nitrate, several amino acids, and starch. We additionally determined the maximal catalytic activities of a wide range of enzymes of primary metabolism, performed targeted quantitative PCR analysis on all three isoforms of citrate synthase, and conducted a broader transcript profiling using the TOM1 microarray. Results from these studies confirmed that if the lines were somewhat impaired in nitrate assimilation, they were not severely affected by this, suggesting the presence of strategies by which metabolism is reprogrammed to compensate for this deficiency. The results are discussed in the context of carbon-nitrogen interaction and interorganellar coordination of metabolism.

  18. Crystal structure of caesium di­hydrogen citrate from laboratory X-ray powder diffraction data and DFT comparison

    PubMed Central

    Kaduk, James A.

    2017-01-01

    The crystal structure of caesium di­hydrogen citrate, Cs+·H2C6H5O7 −, has been solved and refined using laboratory X-ray powder diffraction data, and optimized using density functional techniques. The coordination polyhedra of the nine-coordinate Cs+ cations share edges to form chains along the a-axis. These chains are linked by corners along the c-axis. The un-ionized carb­oxy­lic acid groups form two different types of hydrogen bonds; one forms a helical chain along the c-axis, and the other is discrete. The hy­droxy group participates in both intra- and inter­molecular hydrogen bonds. PMID:28217327

  19. Crystal structure of dirubidium hydrogen citrate from laboratory X-ray powder diffraction data and DFT comparison

    PubMed Central

    Rammohan, Alagappa; Kaduk, James A.

    2017-01-01

    The crystal structure of dirubidium hydrogen citrate, 2Rb+·HC6H5O7 2−, has been solved and refined using laboratory X-ray powder diffraction data, and optimized using density functional techniques. The un-ionized carb­oxy­lic acid group forms helical chains of very strong hydrogen bonds (O⋯O ∼ 2.42 Å) along the b axis. The hy­droxy group participates in a chain of intra- and inter­molecular hydrogen bonds along the c axis. These hydrogen bonds result in corrugated hydrogen-bonded layers in the bc plane. The Rb+ cations are six-coordinate, and share edges and corners to form layers in the ab plane. The inter­layer contacts are composed of the hydro­phobic methyl­ene groups. PMID:28083145

  20. Crystal structure of caesium di-hydrogen citrate from laboratory X-ray powder diffraction data and DFT comparison.

    PubMed

    Rammohan, Alagappa; Kaduk, James A

    2017-02-01

    The crystal structure of caesium di-hydrogen citrate, Cs(+)·H2C6H5O7(-), has been solved and refined using laboratory X-ray powder diffraction data, and optimized using density functional techniques. The coordination polyhedra of the nine-coordinate Cs(+) cations share edges to form chains along the a-axis. These chains are linked by corners along the c-axis. The un-ionized carb-oxy-lic acid groups form two different types of hydrogen bonds; one forms a helical chain along the c-axis, and the other is discrete. The hy-droxy group participates in both intra- and inter-molecular hydrogen bonds.

  1. Crystal structure of dirubidium hydrogen citrate from laboratory X-ray powder diffraction data and DFT comparison.

    PubMed

    Rammohan, Alagappa; Kaduk, James A

    2017-01-01

    The crystal structure of dirubidium hydrogen citrate, 2Rb(+)·HC6H5O7(2-), has been solved and refined using laboratory X-ray powder diffraction data, and optimized using density functional techniques. The un-ionized carb-oxy-lic acid group forms helical chains of very strong hydrogen bonds (O⋯O ∼ 2.42 Å) along the b axis. The hy-droxy group participates in a chain of intra- and inter-molecular hydrogen bonds along the c axis. These hydrogen bonds result in corrugated hydrogen-bonded layers in the bc plane. The Rb(+) cations are six-coordinate, and share edges and corners to form layers in the ab plane. The inter-layer contacts are composed of the hydro-phobic methyl-ene groups.

  2. iTRAQ analysis of low-phytate mung bean sprouts treated with sodium citrate, sodium acetate and sodium tartrate.

    PubMed

    Jin, Xiaolin; Yang, Runqiang; Guo, Liping; Wang, Xinkun; Yan, Xiaokun; Gu, Zhenxin

    2017-03-01

    The effects of sodium citrate (SC), sodium acetate (SA) and sodium tartrate (ST) spraying on mung bean germination were investigated. Exogenous SC, ST and SA treatments significantly reduced the phytic acid content and increased the antioxidant enzyme activities. In this study, an iTRAQ-based proteomic approach was employed to explore the proteomes of mung bean sprouts, and 81, 101 and 90 differentially expressed proteins were identified in 4-day-old SC-, SA- and ST-treated mung bean sprouts, with 38 proteins present in all samples. Functional classification analysis showed that most of the differentially expressed proteins in mung bean sprouts subjected to the three treatments were involved in carbohydrate and energy metabolism. The inhibitory effect of the SA treatment was probably due to impairments in protein biosynthesis, whereas enhanced energy metabolism, accelerated reserve hydrolysis and protein processing were very important strategies for growth stimulation in response to ST and SC treatments.

  3. OsFRDL1 is a citrate transporter required for efficient translocation of iron in rice.

    PubMed

    Yokosho, Kengo; Yamaji, Naoki; Ueno, Daisei; Mitani, Namiki; Ma, Jian Feng

    2009-01-01

    Multidrug and toxic compound extrusion (MATE) transporters represent a large family in plants, but their functions are poorly understood. Here, we report the function of a rice (Oryza sativa) MATE gene (Os03g0216700, OsFRDL1), the closest homolog of barley (Hordeum vulgare) HvAACT1 (aluminum [Al]-activated citrate transporter 1), in terms of metal stress (iron [Fe] deficiency and Al toxicity). This gene was mainly expressed in the roots and the expression level was not affected by either Fe deficiency or Al toxicity. Knockout of this gene resulted in leaf chlorosis, lower leaf Fe concentration, higher accumulation of zinc and manganese concentration in the leaves, and precipitation of Fe in the root's stele. The concentration of citrate and ferric iron in the xylem sap was lower in the knockout line compared to the wild-type rice. Heterologous expression of OsFRDL1 in Xenopus oocytes showed transport activity for citrate. Immunostaining showed that OsFRDL1 was localized at the pericycle cells of the roots. On the other hand, there was no difference in the Al-induced secretion of citrate from the roots between the knockout line and the wild-type rice. Taken together, our results indicate that OsFRDL1 is a citrate transporter localized at the pericycle cells, which is necessary for efficient translocation of Fe to the shoot as a Fe-citrate complex.

  4. Assessment of Multiplate® platelet aggregometry using Citrate, Heparin or Hirudin in Rhesus macaques

    PubMed Central

    Dugan, Greg; O’Donnell, Lisa; Hanbury, David B.; Cline, J. Mark; Caudell, David L.

    2016-01-01

    Electrical impedance aggregometry (EIA) has gained popularity for clinical and research applications. Nonhuman primates are used to study disease and drug-related mechanisms that affect hemostasis, therefore normal establishing normal EIA parameters are necessary. The anticoagulants sodium heparin, hirudin and sodium citrate and three agonists, ADP, ASPI, and collagen were evaluated. Whole blood from 12 adult male rhesus macaques was collected to evaluate anticoagulants, sodium heparin, hirudin and sodium citrate using three agonists (ADP, ASPI and collagen), on the Multiplate® 5.0 Analyzer. Platelet function was reported for three parameters: Area under the curve (AUC), aggregation, and aggregation velocity. There was a significant difference in mean AUC between citrate and heparin samples, and citrate and hirudin samples regardless of the agonist used. There was no difference in AUC between heparin and hirudin. ADP-activated samples showed an increase in impedance with hirudin samples compared to citrate. Furthermore heparin and hirudin out-perform citrate as the anticoagulant for EIA in the macaque. Finally, this study demonstrates the utility of the Multiplate® system in this model and provides important insight into anticoagulant choice when using EIA. PMID:25549285

  5. Citrate and celecoxib induce apoptosis and decrease necrosis in synergistic manner in canine mammary tumor cells.

    PubMed

    Vahidi, R; Safi, S; Farsinejad, A; Panahi, N

    2015-10-16

    Celecoxib and citrate have been shown to possess antitumor activity in a variety of cancer cells. However, the antitumor activities of these agents in canine mammary tumors have not been well demonstrated. The aim of our study was to investigate the apoptotic and antiproliferative effects of citrate and celecoxib, individually and in combination, on canine mammary tumor cell line CF41—Mg. MTT assay was performed to determine cell viability, and Annexin—PI test was performed to evaluate apoptosis induction. MTT assay results revealed that compared with the control groups, treatment groups, as both single and combined treatments, showed significant inhibition of tumor growth in a dose—dependent manner. IC50 concentrations of citrate and celecoxib were defined 26mM and 22μM, respectively. In another set of experiment, significant increase in cell apoptosis was observed at IC50 concentrations of citrate and celecoxib after 48h incubation. In spite of that, simultaneous treatment of cells with citrate and celecoxib eventuated with meaningful toxicity augmentation and induction of apoptosis at lower concentrations. Also necrotic cells were decreased by coadministration of the two agents. In conclusion, the present study indicates significant cytotoxic and apoptotic effects of citrate and celecoxib coadministration on CF41—Mg cells, and proposes new strategies for counteracting cancer cells proliferation and overcoming chemo resistance.

  6. SbnG, a citrate synthase in Staphylococcus aureus: A new fold on an old enzyme

    DOE PAGES

    Kobylarz, Marek J.; Grigg, Jason C.; Sheldon, Jessica R.; ...

    2014-10-21

    In response to iron deprivation, Staphylococcus aureus produces staphyloferrin B, a citrate-containing siderophore that delivers iron back to the cell. This bacterium also possesses a second citrate synthase, SbnG, that is necessary for supplying citrate to the staphyloferrin B biosynthetic pathway. In this paper, we present the structure of SbnG bound to the inhibitor calcium and an active site variant in complex with oxaloacetate. The overall fold of SbnG is structurally distinct from TCA cycle citrate synthases yet similar to metal-dependent class II aldolases. Phylogenetic analyses revealed that SbnG forms a separate clade with homologs from other siderophore biosynthetic genemore » clusters and is representative of a metal-independent subgroup in the phosphoenolpyruvate/pyruvate domain superfamily. Finally, a structural superposition of the SbnG active site to TCA cycle citrate synthases and site-directed mutagenesis suggests a case for convergent evolution toward a conserved catalytic mechanism for citrate production.« less

  7. Clinical review: Anticoagulation for continuous renal replacement therapy - heparin or citrate?

    PubMed Central

    2011-01-01

    Heparin is the most commonly prescribed anticoagulant for continuous renal replacement therapy. There is, however, increasing evidence questioning its safety, particularly in the critically ill. Heparin mainly confers its anticoagulant effect by binding to antithrombin. Heparin binds to numerous other proteins and cells as well, however, compromising its efficacy and safety. Owing to antithrombin consumption and degradation, and to the binding of heparin to acute phase proteins, and to apoptotic and necrotic cells, critical illness confers heparin resistance. The nonspecific binding of heparin further leads to an unpredictable interference with inflammation pathways, microcirculation and phagocytotic clearance of dead cells, with possible deleterious consequences for patients with sepsis and systemic inflammation. Regional anticoagulation with citrate does not increase the patient's risk of bleeding. The benefits of citrate further include a longer or similar circuit life, and possibly better patient and kidney survival. This needs to be confirmed in larger randomized controlled multicenter trials. The use of citrate might be associated with less inflammation and has useful bio-energetic implications. Citrate can, however, with inadequate use cause metabolic derangements. Full advantages of citrate can only be realized if its risks are well controlled. These observations suggest a greater role for citrate. PMID:21345279

  8. Transformations of citrate and Tween coated silver nanoparticles reacted with Na₂S.

    PubMed

    Baalousha, M; Arkill, K P; Romer, I; Palmer, R E; Lead, J R

    2015-01-01

    Silver nanoparticles (Ag NPs) are susceptible to transformations in environmental and biological media such as aggregation, oxidation, dissolution, chlorination, sulfidation, formation/replacement of surface coatings following interaction with natural organic matter (NOM). This paper investigates the impact of surface coating and Suwannee River fulvic acid (SRFA) on the transformations and behavior of Ag NPs (citrate coated and Tween coated; cit-Ag NPs and Tween-Ag NPs, respectively), following reaction with different concentrations of Na2S solution (as a source of sulfide species, H2S and HS(-)). These transformations and the dominant mechanisms of transformations were investigated using UV-vis and scanning transmission electron microscopy coupled with electron energy loss spectroscopy. Here, we have shown that Ag NP surface coating impacts their dissolution following dilution in ultrahigh purity water, with higher extent of dissolution of Tween-Ag NPs compared with cit-Ag NPs. Tween-Ag NPs are susceptible to dissolution following their sulfidation at low S/Ag molar ratio. Suwannee River fulvic acid (SRFA) slows down the dissolution of Tween-Ag NPs at low sulfide concentrations and reduces the aggregation of cit-Ag NP in the presence of sodium sulfide. Sulfidation appears to occur by direct interaction of sulfide species with Ag NPs rather than by indirect reaction of sulfide with dissolved Ag species subsequent to dissolution. Furthermore, the sulfidation process results in the formation of partially sulfidized Ag NPs containing unreacted (metallic) subgrains at the edge of the NPs for Tween-Ag NPs in the presence of high sulfide concentration (2000nM Na2S), which occurred to less extent at lower Na2S concentration for Tween-Ag NPs and at all concentrations of Na2S for cit-Ag NPs. Thus, sulfidized Ag NPs may preserve some of the properties of the Ag NPs such as their potential to shed Ag(+) ions and their toxic potential of Ag NPs.

  9. Mitochondrial Citrate Transporter-dependent Metabolic Signature in the 22q11.2 Deletion Syndrome*

    PubMed Central

    Napoli, Eleonora; Tassone, Flora; Wong, Sarah; Angkustsiri, Kathleen; Simon, Tony J.; Song, Gyu; Giulivi, Cecilia

    2015-01-01

    The congenital disorder 22q11.2 deletion syndrome (22qDS), characterized by a hemizygous deletion of 1.5–3 Mb on chromosome 22 at locus 11.2, is the most common microdeletion disorder (estimated prevalence of 1 in 4000) and the second risk factor for schizophrenia. Nine of ∼30 genes involved in 22qDS have the potential of disrupting mitochondrial metabolism (COMT, UFD1L, DGCR8, MRPL40, PRODH, SLC25A1, TXNRD2, T10, and ZDHHC8). Deficits in bioenergetics during early postnatal brain development could set the basis for a disrupted neuronal metabolism or synaptic signaling, partly explaining the higher incidence in developmental and behavioral deficits in these individuals. Here, we investigated whether mitochondrial outcomes and metabolites from 22qDS children segregated with the altered dosage of one or several of these mitochondrial genes contributing to 22qDS etiology and/or morbidity. Plasma metabolomics, lymphocytic mitochondrial outcomes, and epigenetics (histone H3 Lys-4 trimethylation and 5-methylcytosine) were evaluated in samples from 11 22qDS children and 13 age- and sex-matched neurotypically developing controls. Metabolite differences between 22qDS children and controls reflected a shift from oxidative phosphorylation to glycolysis (higher lactate/pyruvate ratios) accompanied by an increase in reductive carboxylation of α-ketoglutarate (increased concentrations of 2-hydroxyglutaric acid, cholesterol, and fatty acids). Altered metabolism in 22qDS reflected a critical role for the haploinsufficiency of the mitochondrial citrate transporter SLC25A1, further enhanced by HIF-1α, MYC, and metabolite controls. This comprehensive profiling served to clarify the biochemistry of this disease underlying its broad, complex phenotype. PMID:26221035

  10. 21 CFR 172.755 - Stearyl monoglyceridyl citrate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Monoglycerides of fatty acids Prepared by the glycerolysis of edible fats and oils or derived from fatty acids conforming with § 172.860. Stearyl alcohol Derived from fatty acids conforming with § 172.860, or derived... for use as an emulsion stabilizer in or with shortenings containing emulsifiers....

  11. Transcriptomic analysis of the role of carboxylic acids in metabolite signaling in Arabidopsis leaves.

    PubMed

    Finkemeier, Iris; König, Ann-Christine; Heard, William; Nunes-Nesi, Adriano; Pham, Phuong Anh; Leister, Dario; Fernie, Alisdair R; Sweetlove, Lee J

    2013-05-01

    The transcriptional response to metabolites is an important mechanism by which plants integrate information about cellular energy and nutrient status. Although some carboxylic acids have been implicated in the regulation of gene expression for select transcripts, it is unclear whether all carboxylic acids have the same effect, how many transcripts are affected, and how carboxylic acid signaling is integrated with other metabolite signals. In this study, we demonstrate that perturbations in cellular concentrations of citrate, and to a lesser extent malate, have a major impact on nucleus-encoded transcript abundance. Functional categories of transcripts that were targeted by both organic acids included photosynthesis, cell wall, biotic stress, and protein synthesis. Specific functional categories that were only regulated by citrate included tricarboxylic acid cycle, nitrogen metabolism, sulfur metabolism, and DNA synthesis. Further quantitative real-time polymerase chain reaction analysis of specific citrate-responsive transcripts demonstrated that the transcript response to citrate is time and concentration dependent and distinct from other organic acids and sugars. Feeding of isocitrate as well as the nonmetabolizable citrate analog tricarballylate revealed that the abundance of selected marker transcripts is responsive to citrate and not downstream metabolites. Interestingly, the transcriptome response to citrate feeding was most similar to those observed after biotic stress treatments and the gibberellin biosynthesis inhibitor paclobutrazol. Feeding of citrate to mutants with defects in plant hormone signaling pathways did not completely abolish the transcript response but hinted at a link with jasmonic acid and gibberellin signaling pathways. Our results suggest that changes in carboxylic acid abundances can be perceived and signaled in Arabidopsis (Arabidopsis thaliana) by as yet unknown signaling pathways.

  12. Synthesis of nanocrystalline Ba(MnTi) xFe 12-2 xO 19 powders by the sol-gel combustion method in citrate acid-metal nitrates system ( x=0, 0.5, 1.0, 1.5, 2.0)

    NASA Astrophysics Data System (ADS)

    Hong, Y. S.; Ho, C. M.; Hsu, H. Y.; Liu, C. T.

    2004-08-01

    Nano-size M-type hexaferrites Ba(MnTi) xFe 12-2 xO 19 powders are synthesized by using the sol-gel combustion method in nitrate citric acid systems. The spectra of FTIR, TGA, and DSC indicate that citric acid and nitrate ion were decomposed at the temperature between 170°C and 200°C. The largest exothermic peaks at 180-270°C, which are due to the combustion reaction between decomposed citric acid and nitrate, were observed in DSC curves. The X-ray diffraction patterns of Ba(MnTi) xFe 12-2 xO 19 annealed above 800°C manifest that all the species have hexagonal crystal structure with lattice constants of a=5.89-5.91 and c=23.11-23.28 Å. TEM observation of as-burnt powders of Ba(MnTi)Fe 12O 19 shows the powder particles have an average particle size of 50 nm. Magnetic hysteresis loop measurements of the series Ba(MnTi) xFe 12-2 xO 19, x=0.5-2.0, exhibit that the saturation magnetization ( Ms), the remanent magnetization ( Mr) and the coercitivity ( Hc) of compounds depend strongly on the chemical composition of materials. The maxium values of Ms (67.6 emu/g) and Mr (32.7 emu/g) of this series of compounds were found at x=1.0; however, the values of Hc and the areas of magnetic hysteresis loop of compounds decrease with increasing the value of x.

  13. Potassium citrate decreases urine calcium excretion in patients with hypocitraturic calcium oxalate nephrolithiasis.

    PubMed

    Song, Yan; Hernandez, Natalia; Shoag, Jonathan; Goldfarb, David S; Eisner, Brian H

    2016-04-01

    Two previous studies (<10 patients each) have demonstrated that alkali therapy may reduce urine calcium excretion in patients with calcium oxalate nephrolithiasis. The hypothesized mechanisms are (1) a decrease in bone turnover due to systemic alkalinization by the medications; (2) binding of calcium by citrate in the gastrointestinal tract; (3) direct effects on TRPV5 activity in the distal tubule. We performed a retrospective review of patients on potassium citrate therapy to evaluate the effects of this medication on urinary calcium excretion. A retrospective review was performed of a metabolic stone database at a tertiary care academic hospital. Patients were identified with a history of calcium oxalate nephrolithiasis and hypocitraturia who were on potassium citrate therapy for a minimum of 3 months. 24-h urine composition was assessed prior to the initiation of potassium citrate therapy and after 3 months of therapy. Patients received 30-60 mEq potassium citrate by mouth daily. Inclusion criterion was a change in urine potassium of 20 mEq/day or greater, which suggests compliance with potassium citrate therapy. Paired t test was used to compare therapeutic effect. Twenty-two patients were evaluated. Mean age was 58.8 years (SD 14.0), mean BMI was 29.6 kg/m(2) (SD 5.9), and gender prevalence was 36.4% female:63.6% male. Mean pre-treatment 24-h urine values were as follows: citrate 280.0 mg/day, potassium 58.7 mEq/day, calcium 216.0 mg/day, pH 5.87. Potassium citrate therapy was associated with statistically significant changes in each of these parameters-citrate increased to 548.4 mg/day (p < 0.0001), potassium increased to 94.1 mEq/day (p < 0.0001), calcium decreased to 156.5 mg/day (p = 0.04), pH increased to 6.47 (p = 0.001). Urine sodium excretion was not different pre- and post-therapy (175 mEq/day pre-therapy versus 201 mEq/day post-therapy, p = NS). Urinary calcium excretion decreased by a mean of 60 mg/day on potassium citrate therapy-a nearly 30

  14. Sensitive and selective SERS probe for trivalent chromium detection using citrate attached gold nanoparticles

    NASA Astrophysics Data System (ADS)

    Ye, Yingjie; Liu, Honglin; Yang, Liangbao; Liu, Jinhuai

    2012-09-01

    In this article, we have demonstrated a sensitive and selective surface enhanced Raman spectroscopy (SERS) probe, based on citrate-capped gold nanoparticles (AuNPs), for trivalent chromium (Cr3+) detection. After introducing Tween 20 to a solution of citrate-capped AuNPs, the as-prepared Tween 20/citrate-AuNP probe could recognize Cr3+ at a 50 × 10-9 M level in an aqueous medium at a pH of 6.0. Tween 20 can stabilize the citrate-capped AuNPs against conditions of high ionic strength. Due to the chelation between Cr3+ and citrate ions, AuNPs undergo aggregation. As a result, it formed several hot spots and provided a significant enhancement of the Raman signal intensity through electromagnetic (EM) field enhancements. A detailed mechanism for tremendous SERS intensity change had been discussed. The selectivity of this system toward Cr3+ was 400-fold, remarkably greater than other metal ions.In this article, we have demonstrated a sensitive and selective surface enhanced Raman spectroscopy (SERS) probe, based on citrate-capped gold nanoparticles (AuNPs), for trivalent chromium (Cr3+) detection. After introducing Tween 20 to a solution of citrate-capped AuNPs, the as-prepared Tween 20/citrate-AuNP probe could recognize Cr3+ at a 50 × 10-9 M level in an aqueous medium at a pH of 6.0. Tween 20 can stabilize the citrate-capped AuNPs against conditions of high ionic strength. Due to the chelation between Cr3+ and citrate ions, AuNPs undergo aggregation. As a result, it formed several hot spots and provided a significant enhancement of the Raman signal intensity through electromagnetic (EM) field enhancements. A detailed mechanism for tremendous SERS intensity change had been discussed. The selectivity of this system toward Cr3+ was 400-fold, remarkably greater than other metal ions. Electronic supplementary information (ESI) available: Fig. S1-S5. See DOI: 10.1039/c2nr31985c

  15. Sildenafil citrate attenuates the deleterious effects of elevated ammonia.

    PubMed

    Arafa, Manar H; Atteia, Hebatallah H

    2013-07-01

    Ammonia is a bi-product of protein metabolism in the body. It is able to cross the blood-brain barrier and elevated ammonia levels are toxic to the brain. Rats with hyperammonemia showed impaired learning ability and impaired function of the glutamate-nitric oxide-cyclic guanosine monophosphate (glutamate-NO-cGMP) pathway in the brain. Chronic treatment with sildenafil restored learning ability. We therefore tested the hypothesis that sildenafil has a protective effect on the brains of hyperammonemic rats. Hyperammonemia was induced in male rats by daily intraperitoneal (i.p.) injection of ammonium chloride (100 mg/kg body weight) for 8 weeks. Sildenafil citrate was administered intraperitoneally (10 mg/kg body weight/3 days) for 8 weeks. Treatment with sildenafil resulted in a significant reduction in plasma liver enzymes, lipid profile as well as brain lipid peroxidation and caspase-3 mRNA. Meanwhile, plasma NO as well as cGMP, antioxidants and endothelial nitric oxide synthase (eNOS) gene expression were significantly elevated in the brains of hyperammonemic rats. Our results showed that sildenafil exerts a protective effect on the brain by reversing oxidative stress during hyperammonemia and this could be due to (i) cytoprotective, antioxidant and anti-apoptotic effects (ii) increasing cGMP and enhancing the proper metabolism of fats which could suppress oxygen radical generation and thus preventing oxidative damage in the brain. The exact protective mechanism of sildenafil has to be still investigated and further studies are warranted. Consequently, therapeutic modulation of the NO/cGMP pathway might have important clinical applications to improve brain functions in patients with hyperammonemia or clinical hepatic encephalopathy.

  16. Transport of citrate-coated silver nanoparticles in unsaturated sand.

    PubMed

    Kumahor, Samuel K; Hron, Pavel; Metreveli, George; Schaumann, Gabriele E; Vogel, Hans-Jörg

    2015-12-01

    Chemical factors and physical constraints lead to coupled effects during particle transport in unsaturated porous media. Studies on unsaturated transport as typical for soils are currently scarce. In unsaturated porous media, particle mobility is determined by the existence of an air-water interface in addition to a solid-water interface. To this end, we measured breakthrough curves and retention profiles of citrate-coated Ag nanoparticles in unsaturated sand at two pH values (5 and 9) and three different flow rates corresponding to different water contents with 1 mM KNO3 as background electrolyte. The classical DLVO theory suggests unfavorable deposition conditions at the air-water and solid-water interfaces. The breakthrough curves indicate modification in curve shapes and retardation of nanoparticles compared to inert solute. Retention profiles show sensitivity to flow rate and pH and this ranged from almost no retention for the highest flow rate at pH=9 to almost complete retention for the lowest flow rate at pH=5. Modeling of the breakthrough curves, thus, required coupling two parallel processes: a kinetically controlled attachment process far from equilibrium, responsible for the shape modification, and an equilibrium sorption, responsible for particle retardation. The non-equilibrium process and equilibrium sorption are suggested to relate to the solid-water and air-water interfaces, respectively. This is supported by the DLVO model extended for hydrophobic interactions which suggests reversible attachment, characterized by a secondary minimum (depth 3-5 kT) and a repulsive barrier at the air-water interface. In contrast, the solid-water interface is characterized by a significant repulsive barrier and the absence of a secondary minimum suggesting kinetically controlled and non-equilibrium interaction. This study provides new insights into particle transport in unsaturated porous media and offers a model concept representing the relevant processes.

  17. Testosterone restoration using enclomiphene citrate in men with secondary hypogonadism: a pharmacodynamic and pharmacokinetic study

    PubMed Central

    Wiehle, Ronald; Cunningham, Glenn R; Pitteloud, Nelly; Wike, Jenny; Hsu, Kuang; Fontenot, Gregory K; Rosner, Michele; Dwyer, Andrew; Podolski, Joseph

    2013-01-01

    Objectives To determine the pharmacodynamic profile of serum total testosterone and luteinizing hormone (LH) levels in men with secondary hypogonadism after initial and chronic daily oral doses of enclomiphene citrate vs transdermal testosterone. To determine the effects of daily oral doses of enclomiphene citrate in comparison with transdermal testosterone on other hormones and markers in men with secondary hypogonadism. Patients and Methods This was a randomized, single-blind, two-centre, phase II study to evaluate the effects of three different doses of enclomiphene citrate (6.25, 12.5 and 25 mg) vs transdermal testosterone on 24-h LH and total testosterone in otherwise normal healthy men with secondary hypogonadism. Forty-eight men were enrolled in the trial (the intent-to-treat population), but four men had testosterone levels >350 ng/dL at baseline. Forty-four men completed the study per protocol. All subjects enrolled in this trial had serum total testosterone in the low range (<350 ng/dL) and had low to normal LH (<12 IU/L) on at least two occasions. Total testosterone and LH levels were assessed each hour for 24 h to examine the effects at each of three treatment doses of enclomiphene citrate vs a standard dose (5 g) of transdermal testosterone. In the initial profile, total testosterone and LH were determined in a naïve population after a single initial oral or transdermal treatment (day 1). This was contrasted to that seen after 6 weeks of continuous daily oral or transdermal treatment (day 42). The pharmacokinetics of enclomiphene citrate were assessed in a select subpopulation. Serum samples were obtained over the course of the study to determine the levels of various hormones and lipids. Results After 6 weeks of continuous use, the mean (sd) concentration of total testosterone at day 42 was 604 (160) ng/dL for men taking the highest dose of enclomiphene citrate (enclomiphene citrate, 25 mg daily) and 500 (278) ng in those men treated with transdermal

  18. Influence of ingestion of aluminum, citric acid and soil on mineral metabolism of lactating beef cows.

    PubMed

    Allen, V G; Horn, F P; Fontenot, J P

    1986-05-01

    Lactating beef cows (16 Hereford and 34 Angus, 430 kg average body weight, aged 8 to 10 yr) were fed a basal diet containing 200 micrograms/g Al alone or supplemented with Al-citrate, citric acid, soil or soil plus citric acid for 56 d. Diets containing Al-citrate, soil and soil plus citric acid contained 1,730, 1,870 and 1,935 micrograms/g Al, dry-basis, respectively. Adding soil to the diet also increased Mg and Fe content of the diet. Aluminum values in ruminal contents of beef cows fed the basal alone or supplemented with citric acid, Al-citrate, soil or soil plus citric acid were 800, 990, 2,930, 3,410 and 2,910 micrograms/g, air-dry basis, respectively. Serum Mg and inorganic P declined (P less than .01) and urinary Ca concentration increased (P less than .01) for cows fed Al-citrate. By d 56, serum Mg was 1.5 and 2.2 mg/dl, and serum P was 3.8 and 6.8 mg/dl, for cows fed Al-citrate and basal diets, respectively. Calcium concentrations in urine were 281 and 11 micrograms/g for cows fed Al-citrate and basal diets, respectively. Citric acid, soil and soil plus citric acid had no detrimental effects on serum Mg and inorganic P, or urinary Ca concentration. By d 56, serum Ca was higher (P less than .06) in cows fed Al-citrate, compared with cows on the other four diets. Bone Ca, P, Zn and percent ash were not significantly affected by treatment but bone Mg tended to be slightly lower (P less than .07) for cows fed Al-citrate.(ABSTRACT TRUNCATED AT 250 WORDS)

  19. Protective effects of sildenafil citrate administration on cisplatin-induced ovarian damage in rats.

    PubMed

    Taskin, Mine Islimye; Yay, Arzu; Adali, Ertan; Balcioglu, Esra; Inceboz, Umit

    2015-04-01

    The aim of this study is to evaluate the effects of sildenafil citrate on cisplatin-induced ovarian toxicity. Thirty-two female rats were divided into four groups. Group 1: saline control; group 2: cisplatin; group 3: sildenafil citrate; and group 4: cisplatin plus sildenafil citrate group. In groups 2 and 4, the rats were injected with 5 mg/kg cisplatin intraperitoneally (i.p.). In groups 3 and 4, the rats were injected with 1.4 mg/kg sildenafil citrate i.p. The ovaries were removed two weeks later in all groups. Histopathologic examination, follicle counting and classification were performed. The expression of anti-Müllerian hormone (AMH) was detected immunohistochemically in the ovarian tissues. Sildenafil alleviated cisplatin-induced histopathological changes in the ovarian tissue. Primordial, secondary and tertiary follicles were diminished in group 2 compared with group 1 (p < 0.05). Pretreatment with sildenafil citrate preserved primordial follicle count in group 4 compared with group 2, and the difference was statistically significant (p < 0.05). According to our results, immunoreactivity intensity of AMH was lower in group 2 compared with group 1 (92.4 ± 3.97 versus 88.8 ± 1.77) but not significantly, whereas immunoreactivity intensity of AMH was higher in group 4 compared with group 2 (88.8 ± 1.77 versus 94.1 ± 2.36; p < 0.05). Our results demonstrated that pretreatment with sildenafil citrate is beneficial for protecting the ovaries from cisplatin-induced damage. Sildenafil citrate can be a choice for fertility preservation.

  20. Localization of the calcium-regulated citrate transport process in proximal tubule cells.

    PubMed

    Hering-Smith, Kathleen S; Mao, Weibo; Schiro, Faith R; Coleman-Barnett, Joycelynn; Pajor, Ana M; Hamm, L Lee

    2014-06-01

    Urinary citrate is an important inhibitor of calcium-stone formation. Most of the citrate reabsorption in the proximal tubule is thought to occur via a dicarboxylate transporter NaDC1 located in the apical membrane. OK cells, an established opossum kidney proximal tubule cell line, transport citrate but the characteristics change with extracellular calcium such that low calcium solutions stimulate total citrate transport as well as increase the apparent affinity for transport. The present studies address several fundamental properties of this novel process: the polarity of the transport process, the location of the calcium-sensitivity and whether NaDC1 is present in OK cells. OK cells grown on permeable supports exhibited apical >basolateral citrate transport. Apical transport of both citrate and succinate was sensitive to extracellular calcium whereas basolateral transport was not. Apical calcium, rather than basolateral, was the predominant determinant of changes in transport. Also 2,3-dimethylsuccinate, previously identified as an inhibitor of basolateral dicarboxylate transport, inhibited apical citrate uptake. Although the calcium-sensitive transport process in OK cells is functionally not typical NaDC1, NaDC1 is present in OK cells by Western blot and PCR. By immunolocalization studies, NaDC1 was predominantly located in discrete apical membrane or subapical areas. However, by biotinylation, apical NaDC1 decreases in the apical membrane with lowering calcium. In sum, OK cells express a calcium-sensitive/regulated dicarboxylate process at the apical membrane which responds to variations in apical calcium. Despite the functional differences of this process compared to NaDC1, NaDC1 is present in these cells, but predominantly in subapical vesicles.