Evaluation of the sorption of Eu(III) in titanium diphosphate

International Nuclear Information System (INIS)

Ortiz O, H.B.; Ordonez R, E.; Fernandez V, S.M.

2007-01-01

In this work its are presented: the synthesis, physicochemical characterization and the surface parameters estimation that can be related with the retention properties of the titanium diphosphate for the actinides of valence III (Pu, Am, Cm among others), using the Eu 3+ like a chemical analog. The surface area, hydration time, zero charge point, density of active sites and the surface species distribution in the titanium diphosphate are reported. This information was used to explain the retention of the Eu(lll) in the surface of the titanium diphosphate. (Author)

PSI1 is responsible for the stearic acid enrichment that is characteristic of phosphatidylinositol in yeast

NARCIS (Netherlands)

Le Guédard, Marina; Bessoule, Jean-Jacques; Boyer, Valérie; Ayciriex, Sophie; Velours, Gisèle; Kulik, Willem; Ejsing, Christer S.; Shevchenko, Andrej; Coulon, Denis; Lessire, René; Testet, Eric

2009-01-01

In yeast, both phosphatidylinositol and phosphatidylserine are synthesized from cytidine diphosphate-diacylglycerol. Because, as in other eukaryotes, phosphatidylinositol contains more saturated fatty acids than phosphatidylserine (and other phospholipids), it has been hypothesized that either

Photoelectron and computational studies of the copper-nucleoside anionic complexes, Cu-(cytidine) and Cu-(uridine)

Science.gov (United States)

Li, Xiang; Ko, Yeon-Jae; Wang, Haopeng; Bowen, Kit H.; Guevara-García, Alfredo; Martínez, Ana

2011-02-01

The copper-nucleoside anions, Cu-(cytidine) and Cu-(uridine), have been generated in the gas phase and studied by both experimental (anion photoelectron spectroscopy) and theoretical (density functional calculations) methods. The photoelectron spectra of both systems are dominated by single, intense, and relatively narrow peaks. These peaks are centered at 2.63 and 2.71 eV for Cu-(cytidine) and Cu-(uridine), respectively. According to our calculations, Cu-(cytidine) and Cu-(uridine) species with these peak center [vertical detachment energy (VDE)] values correspond to structures in which copper atomic anions are bound to the sugar portions of their corresponding nucleosides largely through electrostatic interactions; the observed species are anion-molecule complexes. The combination of experiment and theory also reveal the presence of a slightly higher energy, anion-molecule complex isomer in the case of the Cu-(cytidine). Furthermore, our calculations found that chemically bond isomers of these species are much more stable than their anion-molecule complex counterparts, but since their calculated VDE values are larger than the photon energy used in these experiments, they were not observed.

Photoelectron and computational studies of the copper-nucleoside anionic complexes, Cu(-)(cytidine) and Cu(-)(uridine).

Science.gov (United States)

Li, Xiang; Ko, Yeon-Jae; Wang, Haopeng; Bowen, Kit H; Guevara-García, Alfredo; Martínez, Ana

2011-02-07

The copper-nucleoside anions, Cu(-)(cytidine) and Cu(-)(uridine), have been generated in the gas phase and studied by both experimental (anion photoelectron spectroscopy) and theoretical (density functional calculations) methods. The photoelectron spectra of both systems are dominated by single, intense, and relatively narrow peaks. These peaks are centered at 2.63 and 2.71 eV for Cu(-)(cytidine) and Cu(-)(uridine), respectively. According to our calculations, Cu(-)(cytidine) and Cu(-)(uridine) species with these peak center [vertical detachment energy (VDE)] values correspond to structures in which copper atomic anions are bound to the sugar portions of their corresponding nucleosides largely through electrostatic interactions; the observed species are anion-molecule complexes. The combination of experiment and theory also reveal the presence of a slightly higher energy, anion-molecule complex isomer in the case of the Cu(-)(cytidine). Furthermore, our calculations found that chemically bond isomers of these species are much more stable than their anion-molecule complex counterparts, but since their calculated VDE values are larger than the photon energy used in these experiments, they were not observed.

Choline Magnesium Trisalicylate

Science.gov (United States)

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

Mevalonate 5-diphosphate mediates ATP binding to the mevalonate diphosphate decarboxylase from the bacterial pathogen Enterococcus faecalis

Energy Technology Data Exchange (ETDEWEB)

Chen, Chun-Liang; Mermoud, James C.; Paul, Lake N.; Steussy, Calvin Nicklaus; Stauffacher, Cynthia V. (Purdue)

2017-10-12

The mevalonate pathway produces isopentenyl diphosphate (IPP), a building block for polyisoprenoid synthesis, and is a crucial pathway for growth of the human bacterial pathogen Enterococcus faecalis. The final enzyme in this pathway, mevalonate diphosphate decarboxylase (MDD), acts on mevalonate diphosphate (MVAPP) to produce IPP while consuming ATP. This essential enzyme has been suggested as a therapeutic target for the treatment of drug-resistant bacterial infections. Here, we report functional and structural studies on the mevalonate diphosphate decarboxylase from E. faecalis (MDDEF). The MDDEF crystal structure in complex with ATP (MDDEF–ATP) revealed that the phosphate-binding loop (amino acids 97–105) is not involved in ATP binding and that the phosphate tail of ATP in this structure is in an outward-facing position pointing away from the active site. This suggested that binding of MDDEF to MVAPP is necessary to guide ATP into a catalytically favorable position. Enzymology experiments show that the MDDEF performs a sequential ordered bi-substrate reaction with MVAPP as the first substrate, consistent with the isothermal titration calorimetry (ITC) experiments. On the basis of ITC results, we propose that this initial prerequisite binding of MVAPP enhances ATP binding. In summary, our findings reveal a substrate-induced substrate-binding event that occurs during the MDDEF-catalyzed reaction. The disengagement of the phosphate-binding loop concomitant with the alternative ATP-binding configuration may provide the structural basis for antimicrobial design against these pathogenic enterococci.

Biological function of activation-induced cytidine deaminase (AID

Directory of Open Access Journals (Sweden)

Ritu Kumar

2014-10-01

Full Text Available Activation-induced Cytidine Deaminase (AID is an essential regulator of B cell diversification, but its full range of action has until recently been an enigma. Based on homology, it was originally proposed to be an RNA-editing enzyme, but so far, no RNA substrates are known. Rather, it functions by deaminating cytidine, and in this manner, coupled with base-excision repair or mismatch repair machinery, it is a natural mutator. This allows it to play a central role in adaptive immunity, whereby it initiates the processes of class switch recombination and somatic hypermutation to help generate a diverse and high-affinity repertoire of immunoglobulin isotypes. More recently, it has been appreciated that methylated cytidine, already known as a key epigenetic mark on DNA controlling gene expression, can also be a target for AID modification. Coupled with repair machinery, this can facilitate the active removal of methylated DNA. This activity can impact the process of cellular reprogramming, including transition of a somatic cell to pluripotency, which requires major reshuffling of epigenetic memory. Thus, seemingly disparate roles for AID in controlling immune diversity and epigenetic memory have a common mechanistic basis. However, the very activity that is so useful for B cell diversity and cellular reprogramming is dangerous for the integrity of the genome. Thus, AID expression and activity is tightly regulated, and deregulation is associated with diseases including cancer. Here, we review the range of AID functions with a focus on its mechanisms of action and regulation. Major questions remain to be answered concerning how and when AID is targeted to specific loci and how this impacts development and disease.

The efflux of choline from nerve cells: mediation by ionic gradients and functional exchange of choline from glia to neurons

International Nuclear Information System (INIS)

Hoffmann, D.; Ferret, B.; Massarelli, R.; Mykita, S.

1986-01-01

This paper analyzes the relationship between ions and the efflux of choline, and suggests the possibility of a balance effect for choline fluxes which is produced and maintained by ioinic gradients. It is also suggested that glial cells may actively exchange choline with neurons during nerve actively exchange choline with neurons during nerve activity, and that they may function as a choline reservoir for neuronal needs. The study shows that neurons and glial cells spontaneously discharge choline into the incubation medium. The exiting choline is essentially of free origin, as can be seen in an illustration provided. Neurons and glial cells had been prelabelled with ( 14 C) choline overnight, and labelled for 15 min with tritium-choline. The higher amount of tritium-choline exiting the cells indicates that it is the freshly labelled choline which is preferentially released. The remaining of ( 14 C) - choline exiting the cells corresponds to the free choline of phospholipid origin which amounts to about one third of the total free choline content

Properties of ribulose diphosphate carboxylase immobilized on porous glass

Science.gov (United States)

Shapira, J.; Hanson, C. L.; Lyding, J. M.; Reilly, P. J.

1974-01-01

Ribulose-1,5-diphosphate carboxylase from spinach has been bound to arylamine porous glass with a diazo linkage and to alklamine porous glass with glutaraldehyde. Stability at elevated temperatures and responses to changes of pH and ribulose-1,5-diphosphate, Mg(2+), and dithiothreitol concentrations were not significantly different from the soluble enzyme, though stability at 4 C was somewhat improved.

Dietary Reference Values for choline

DEFF Research Database (Denmark)

Sjödin, Anders Mikael

2016-01-01

Following a request from the European Commission, the EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA) derives Dietary Reference Values (DRVs) for choline. In this Opinion, the Panel considers dietary choline including choline compounds (e.g. glycerophosphocholine, phosphocholine...

APOBEC3 cytidine deaminases in double-strand DNA break repair and cancer promotion.

Science.gov (United States)

Nowarski, Roni; Kotler, Moshe

2013-06-15

High frequency of cytidine to thymidine conversions was identified in the genome of several types of cancer cells. In breast cancer cells, these mutations are clustered in long DNA regions associated with single-strand DNA (ssDNA), double-strand DNA breaks (DSB), and genomic rearrangements. The observed mutational pattern resembles the deamination signature of cytidine to uridine carried out by members of the APOBEC3 family of cellular deaminases. Consistently, APOBEC3B (A3B) was recently identified as the mutational source in breast cancer cells. A3G is another member of the cytidine deaminases family predominantly expressed in lymphoma cells, where it is involved in mutational DSB repair following ionizing radiation treatments. This activity provides us with a new paradigm for cancer cell survival and tumor promotion and a mechanistic link between ssDNA, DSBs, and clustered mutations. Cancer Res; 73(12); 3494-8. ©2013 AACR. ©2013 AACR.

Solid-Phase Synthesis of a New Diphosphate 5-Aminoimidazole-4-carboxamide Riboside (AICAR Derivative and Studies toward Cyclic AICAR Diphosphate Ribose

Directory of Open Access Journals (Sweden)

Gennaro Piccialli

2011-09-01

Full Text Available The solid-phase synthesis of the first example of a new diphosphate AICAR derivative is reported. The new substance is characterized by the presence of a 5'-phosphate group while a second phosphate moiety is installed on a 5-hydroxypentyl chain attached to the 4-N-position of AICAR. Cyclization of the diphosphate derivative by pyrophosphate bond formation allowed for the formation of a novel AICAR-based cyclic ADP-ribose (cADPR mimic.

Choline transport via choline transporter-like protein 1 in conditionally immortalized rat syncytiotrophoblast cell lines TR-TBT.

Science.gov (United States)

Lee, N-Y; Choi, H-M; Kang, Y-S

2009-04-01

Choline is an essential nutrient for phospholipids and acetylcholine biosynthesis in normal development of fetus. In the present study, we investigated the functional characteristics of choline transport system and inhibitory effect of cationic drugs on choline transport in rat conditionally immortalized syncytiotrophoblast cell line (TR-TBT). Choline transport was weakly Na(+) dependent and significantly influenced by extracellular pH and by membrane depolarization. The transport process of choline is saturable with Michaelis-Menten constants (K(m)) of 68microM and 130microM in TR-TBT 18d-1 and TR-TBT 18d-2 respectively. Choline uptake in the cells was inhibited by unlabeled choline and hemicholinium-3 as well as various organic cations including guanidine, amiloride and acetylcholine. However, the prototypical organic cation tetraethylammonium and cimetidine showed very little inhibitory effect of choline uptake in TR-TBT cells. RT-PCR revealed that choline transporter-like protein 1 (CTL1) and organic cation transporter 2 (OCT2) are expressed in TR-TBT cells. The transport properties of choline in TR-TBT cells were similar or identical to that of CTL1 but not OCT2. CTL1 was also detected in human placenta. In addition, several cationic drugs such as diphenhydramine and verapamil competitively inhibited choline uptake in TR-TBT 18d-1 with K(i) of 115microM and 55microM, respectively. Our results suggest that choline transport system, which has intermediate affinity and weakly Na(+) dependent, in TR-TBT seems to occur through a CTL1 and this system may have relevance with the uptake of pharmacologically important organic cation drugs.

Chrysanthemyl diphosphate synthase operates in planta as a bifunctional enzyme with chrysanthemol synthase activity

DEFF Research Database (Denmark)

Yang, Ting; Gao, Liping; Hu, Hao

2014-01-01

Chrysanthemyl diphosphate synthase (CDS) is the first path-way-specific enzyme in the biosynthesis of pyrethrins, the most widely used plant-derived pesticide. CDS catalyzes c1′-2-3 cyclopropanation reactions of two molecules of dimethylallyl diphosphate (DMAPP) to yield chrysanthemyl diphosphate...

Synthesis and behavior at heating of amorphous calcium diphosphate

International Nuclear Information System (INIS)

Levchenko, L.V.; Nurkina, Z.S.; Griggs, D.; Sinyayev, V.A.

2005-01-01

There is description of synthesis of amorphous calcium diphosphate in the article. The compound was received via exchange reaction between sodium diphosphate and calcium chloride in water solution. The results of investigation of behavior when heated of produced substance are presented here as well. Composition and structure of precipitated substances and products of its thermal convention were determined by methods of IR-, NMR 31 P and X-ray spectroscopy

The biosynthetic origin of irregular monoterpenes in Lavandula: isolation and biochemical characterization of a novel cis-prenyl diphosphate synthase gene, lavandulyl diphosphate synthase.

Science.gov (United States)

Demissie, Zerihun A; Erland, Lauren A E; Rheault, Mark R; Mahmoud, Soheil S

2013-03-01

Lavender essential oils are constituted predominantly of regular monoterpenes, for example linalool, 1,8-cineole, and camphor. However, they also contain irregular monoterpenes including lavandulol and lavandulyl acetate. Although the majority of genes responsible for the production of regular monoterpenes in lavenders are now known, enzymes (including lavandulyl diphosphate synthase (LPPS)) catalyzing the biosynthesis of irregular monoterpenes in these plants have not been described. Here, we report the isolation and functional characterization of a novel cis-prenyl diphosphate synthase cDNA, termed Lavandula x intermedia lavandulyl diphosphate synthase (LiLPPS), through a homology-based cloning strategy. The LiLPPS ORF, encoding for a 305-amino acid long protein, was expressed in Escherichia coli, and the recombinant protein was purified by nickel-nitrilotriacetic acid affinity chromatography. The approximately 34.5-kDa bacterially produced protein specifically catalyzed the head-to-middle condensation of two dimethylallyl diphosphate units to LPP in vitro with apparent Km and kcat values of 208 ± 12 μm and 0.1 s(-1), respectively. LiLPPS is a homodimeric enzyme with a sigmoidal saturation curve and Hill coefficient of 2.7, suggesting a positive co-operative interaction among its catalytic sites. LiLPPS could be used to modulate the production of lavandulol and its derivatives in plants through metabolic engineering.

Choline-PET/CT for imaging prostate cancer; Cholin-PET/CT zur Bildgebung des Prostatakarzinoms

Energy Technology Data Exchange (ETDEWEB)

Krause, Bernd Joachim [Klinik- und Poliklinik fuer Nuklearmedizin, Klinikum rechts der Isar, Technische Univ. Muenchen (Germany); Treiber, U.; Schwarzenboeck, S.; Souvatzoglou, M. [Klinik fuer Urologie, Klinikum rechts der Isar, Technische Univ. Muenchen (Germany)

2010-09-15

PET and PET/CT using [{sup 11}C]- and [{sup 18}F]-labelled choline derivatives are increasingly being used for imaging of prostate cancer. The value of PET and PET/CT with [{sup 11}C]- and [{sup 18}F]-labelled choline derivates in biochemical recurrence of prostate cancer has been examined in many studies and demonstrates an increasing importance. Primary prostate cancer can be detected with moderate sensitivity using PET and PET/CT using [{sup 11}C]- and [{sup 18}F]-labelled choline derivatives - the differentiation between benign prostatic hyperplasia, prostatitis or high-grade intraepithelial neoplasia (HGPIN) is not always possible. At the present time [{sup 11}C]choline PET/CT is not recommended in the primary setting but may be utilized in clinically suspected prostate cancer with repeatedly negative prostate biopsies, in preparation of a focused re-biopsy. Promising results have been obtained for the use of PET and PET/CT with [{sup 11}C]- and [{sup 18}F]-labelled choline derivates in patients with biochemical recurrence. The detection rate of choline PET and PET/CT for local, regional, and distant recurrence in patients with a biochemical recurrence shows a linear correlation with PSA values at the time of imaging and reaches about 75% in patients with PSA > 3 ng/mL. At PSA values below 1 ng/mL, the recurrence can be diagnosed with choline PET/CT in approximately 1/3 of the patients. PET and PET/CT with [{sup 11}C]- and [{sup 18}F]choline derivates can be helpful for choosing a therapeutic strategy in the sense of an individualized treatment: since an early diagnosis of recurrence is crucial to the choice of optimal treatment. The localization of the site of recurrence - local recurrence, lymph node metastasis or systemic dissemination - has important influence on the therapy regimen. (orig.)

Isolation and characterization of farnesyl diphosphate synthase from the cotton boll weevil, Anthonomus grandis.

Science.gov (United States)

Taban, A Huma; Tittiger, Claus; Blomquist, Gary J; Welch, William H

2009-06-01

Farnesyl diphosphate synthase (FPPS) catalyzes the consecutive condensation of two molecules of isopentenyl diphosphate with dimethylallyl diphosphate to form farnesyl diphosphate (FPP). In insects, FPP is used for the synthesis of ubiquinones, dolicols, protein prenyl groups, and juvenile hormone. A full-length cDNA of FPPS was cloned from the cotton boll weevil, Anthonomus grandis (AgFPPS). AgFPPS cDNA consists of 1,835 nucleotides and encodes a protein of 438 amino acids. The deduced amino acid sequence has high similarity to previously isolated insect FPPSs and other known FPPSs. Recombinant AgFPPS expressed in E. coli converted labeled isopentenyl diphosphate in the presence of dimethylallyl diphosphate to FPP. Southern blot analysis indicated the presence of a single copy gene. Using molecular modeling, the three-dimensional structure of coleopteran FPPS was determined and compared to the X-ray crystal structure of avian FPPS. The alpha-helical fold is conserved in AgFPPS and the size of the active site cavity is consistent with the enzyme being a FPPS. (c) 2009 Wiley Periodicals, Inc.

Hypermutation by intersegmental transfer of APOBEC3G cytidine deaminase.

Science.gov (United States)

Nowarski, Roni; Britan-Rosich, Elena; Shiloach, Tamar; Kotler, Moshe

2008-10-01

Deamination of cytidine residues in single-stranded DNA (ssDNA) is an important mechanism by which apolipoprotein B mRNA-editing, catalytic polypeptide-like (APOBEC) enzymes restrict endogenous and exogenous viruses. The dynamic process underlying APOBEC-induced hypermutation is not fully understood. Here we show that enzymatically active APOBEC3G can be detected in wild-type Vif(+) HIV-1 virions, albeit at low levels. In vitro studies showed that single enzyme-DNA encounters result in distributive deamination of adjacent cytidines. Nonlinear translocation of APOBEC3G, however, directed scattered deamination of numerous targets along the DNA. Increased ssDNA concentrations abolished enzyme processivity in the case of short, but not long, DNA substrates, emphasizing the key role of rapid intersegmental transfer in targeting the deaminase. Our data support a model by which APOBEC3G intersegmental transfer via monomeric binding to two ssDNA segments results in dispersed hypermutation of viral genomes.

21 CFR 582.5252 - Choline chloride.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Choline chloride. 582.5252 Section 582.5252 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Supplements 1 § 582.5252 Choline chloride. (a) Product. Choline chloride. (b) Conditions of use. This...

Preparation of alpha-5-aza-2'-deoxy-[6-3H]cytidine

Czech Academy of Sciences Publication Activity Database

Elbert, Tomáš; Černý, B.

2008-01-01

Roč. 73, č. 5 (2008), s. 701-704 ISSN 0010-0765 Institutional research plan: CEZ:AV0Z40550506 Keywords : alfa-5aza-2'-deoxy-cytidine Subject RIV: CC - Organic Chemistry Impact factor: 0.784, year: 2008

Choline and Choline Metabolite Patterns and Associations in Blood and Milk during Lactation in Dairy Cows

Science.gov (United States)

Artegoitia, Virginia M.; Middleton, Jesse L.; Harte, Federico M.; Campagna, Shawn R.; de Veth, Michael J.

2014-01-01

Milk and dairy products are an important source of choline, a nutrient essential for human health. Infant formula derived from bovine milk contains a number of metabolic forms of choline, all contribute to the growth and development of the newborn. At present, little is known about the factors that influence the concentrations of choline metabolites in milk. The objectives of this study were to characterize and then evaluate associations for choline and its metabolites in blood and milk through the first 37 weeks of lactation in the dairy cow. Milk and blood samples from twelve Holstein cows were collected in early, mid and late lactation and analyzed for acetylcholine, free choline, betaine, glycerophosphocholine, lysophosphatidylcholine, phosphatidylcholine, phosphocholine and sphingomyelin using hydrophilic interaction liquid chromatography-tandem mass spectrometry, and quantified using stable isotope-labeled internal standards. Total choline concentration in plasma, which was almost entirely phosphatidylcholine, increased 10-times from early to late lactation (1305 to 13,535 µmol/L). In milk, phosphocholine was the main metabolite in early lactation (492 µmol/L), which is a similar concentration to that found in human milk, however, phosphocholine concentration decreased exponentially through lactation to 43 µmol/L in late lactation. In contrast, phosphatidylcholine was the main metabolite in mid and late lactation (188 µmol/L and 659 µmol/L, respectively), with the increase through lactation positively correlated with phosphatidylcholine in plasma (R 2 = 0.78). Unlike previously reported with human milk we found no correlation between plasma free choline concentration and milk choline metabolites. The changes in pattern of phosphocholine and phosphatidylcholine in milk through lactation observed in the bovine suggests that it is possible to manufacture infant formula that more closely matches these metabolites profile in human milk. PMID:25157578

Choline and choline metabolite patterns and associations in blood and milk during lactation in dairy cows.

Directory of Open Access Journals (Sweden)

Virginia M Artegoitia

Full Text Available Milk and dairy products are an important source of choline, a nutrient essential for human health. Infant formula derived from bovine milk contains a number of metabolic forms of choline, all contribute to the growth and development of the newborn. At present, little is known about the factors that influence the concentrations of choline metabolites in milk. The objectives of this study were to characterize and then evaluate associations for choline and its metabolites in blood and milk through the first 37 weeks of lactation in the dairy cow. Milk and blood samples from twelve Holstein cows were collected in early, mid and late lactation and analyzed for acetylcholine, free choline, betaine, glycerophosphocholine, lysophosphatidylcholine, phosphatidylcholine, phosphocholine and sphingomyelin using hydrophilic interaction liquid chromatography-tandem mass spectrometry, and quantified using stable isotope-labeled internal standards. Total choline concentration in plasma, which was almost entirely phosphatidylcholine, increased 10-times from early to late lactation (1305 to 13,535 µmol/L. In milk, phosphocholine was the main metabolite in early lactation (492 µmol/L, which is a similar concentration to that found in human milk, however, phosphocholine concentration decreased exponentially through lactation to 43 µmol/L in late lactation. In contrast, phosphatidylcholine was the main metabolite in mid and late lactation (188 µmol/L and 659 µmol/L, respectively, with the increase through lactation positively correlated with phosphatidylcholine in plasma (R2 = 0.78. Unlike previously reported with human milk we found no correlation between plasma free choline concentration and milk choline metabolites. The changes in pattern of phosphocholine and phosphatidylcholine in milk through lactation observed in the bovine suggests that it is possible to manufacture infant formula that more closely matches these metabolites profile in human milk.

Choline or methionine reverses impaired secretion of VLDL by hepatocytes from choline-deficient rats

International Nuclear Information System (INIS)

Yao, Z.; Vance, D.E.

1987-01-01

Male rats fed a choline-deficient (CD) diet for three days accumulated triacylglycerol (TG) in the liver. Hepatocytes from these rats were cultured and maintained in a medium + choline. The rate of secretion of TG was reduced by 50% in the CD cells. Correspondingly, [ 3 H]oleate and [ 3 H]glycerol were incorporated at a 2-fold higher rate into TG secreted by choline-supplemented cells compared to CD cells. Isolation of lipoprotein fractions by ultracentrifugation showed that the reduced secretion of TG by CD hepatocytes was mainly due to an impaired secretion of very low density lipoprotein (VLDL). Incorporation of [ 3 H]leucine into secreted apoB/sub H/, apoB/sub L/ and apoE was markedly reduced in CD cells compared to choline-supplemented cells. Secretion of high density lipoprotein was not reduced in the CD hepatocytes. Normal secretion of VLDL was resumed upon addition of methionine to the CD cells

Contents of lecithin and choline in crude drugs.

Science.gov (United States)

Yamasaki, K; Kikuoka, M; Nishi, H; Kokusenya, Y; Miyamoto, T; Matsuo, M; Sato, T

1994-01-01

The determination of lecithin and choline in crude drugs was established by a combination of high performance liquid chromatography (HPLC) with electrochemical detector (ECD) and enzyme reaction. Lecithin in crude drugs extracted with a mixture of chloroform-methanol (2:1) at room temperature was hydrolyzed by phospholipase D. The hydrolyzate was injected to HPLC, and choline was separated from impurities by reverse phase column. The choline was converted to betaine and hydrogen peroxide by passing through column packed with immobilized choline oxidase. This hydrogen peroxide was detected by ECD. The peak area of hydrogen peroxide derived from lecithin was proportional to the concentration of lecithin from 0.10 to 1.52 microgram/ml. Choline in crude drugs was extracted with ethanol under reflux and determined under the same HPLC conditions as lecithin. The peak area of hydrogen peroxide derived from choline was proportional to the concentration of choline from 0.01 to 0.45 microgram/ml. The contents of lecithin and choline in 31 kinds of crude drugs were determined by these established methods. The results showed that Cervi Parvum Cornu, Kokurozin, Foenigraeci Semen and Psoraleae Semen contained more lecithin than other crude drugs, while Angelicae Radix, Foenigraeci Semen, Psoraleae Semen, and especially Hippocampus were found to contain more choline than other crude drugs.

RBC-choline: changes by lithium and relation to prophylactic response

International Nuclear Information System (INIS)

Haag, M.; Haag, H.; Eisenried, F.; Greil, W.

1984-01-01

Red blod cell (RBC)- and plasma-choline levels were measured in patients on lithium (n=96), antidepressants (n=32) and neuroleptics (n=51) and in 25 healthy drug-free controls. Lithium patients exhibited highly increased RBC- and slightly increased plasma-choline levels compared with controls (P<0.001 and P<0.05, respectively); the choline ratio (RBC-/plasma-choline) was elevated almost to the same extent as RBC-choline (P<0.001). With antidepressants RBC-choline and choline ratios were slightly reduced (P<0.05), whereas neuroleptics showed no effect on choline levels. 79% of lithium patients were responders (reduction in hospitalizations with lithium) 21% were non-responders (no reduction or increase in hospitalizations). Choline ratio exhibited a significant relation to prophylactic lithium response, but lithium ratio did not. The percentage of non-responders was significantly higher in patients with a choline ratio exceeding 100 than in patients with a choline ratio below this cut-off (P<0.01). Thus, the increase of RBC-choline and choline ratios appears to be an effect specific for lithium and might be related to the outcome of lithium prophylaxis. (author)

Structure and mechanism of the diterpene cyclase ent-copalyl diphosphate synthase

Energy Technology Data Exchange (ETDEWEB)

Köksal, Mustafa; Hu, Huayou; Coates, Robert M.; Peters, Reuben J.; Christianson, David W. (UIUC); (Iowa State); (Penn)

2011-09-20

The structure of ent-copalyl diphosphate synthase reveals three {alpha}-helical domains ({alpha}, {beta} and {gamma}), as also observed in the related diterpene cyclase taxadiene synthase. However, active sites are located at the interface of the {beta}{gamma} domains in ent-copalyl diphosphate synthase but exclusively in the {alpha} domain of taxadiene synthase. Modular domain architecture in plant diterpene cyclases enables the evolution of alternative active sites and chemical strategies for catalyzing isoprenoid cyclization reactions.

Motesanib diphosphate in progressive differentiated thyroid cancer

DEFF Research Database (Denmark)

Sherman, Steven I; Wirth, Lori J; Droz, Jean-Pierre

2008-01-01

BACKGROUND: The expression of vascular endothelial growth factor (VEGF) is characteristic of differentiated thyroid cancer and is associated with aggressive tumor behavior and a poor clinical outcome. Motesanib diphosphate (AMG 706) is a novel oral inhibitor of VEGF receptors, platelet-derived gr...

Heterooligomeric phosphoribosyl diphosphate synthase of Saccharomyces cerevisiae

DEFF Research Database (Denmark)

Hove-Jensen, Bjarne

2004-01-01

The yeast Saccharomyces cerevisiae contains five phosphoribosyl diphosphate (PRPP) synthase-homologous genes (PRS1-5), which specify PRPP synthase subunits 1-5. Expression of the five S. cerevisiae PRS genes individually in an Escherichia coli PRPP-less strain (Deltaprs) showed that a single PRS...

Dysregulated choline metabolism in T-cell lymphoma: role of choline kinase-α and therapeutic targeting

International Nuclear Information System (INIS)

Xiong, J; Bian, J; Wang, L; Zhou, J-Y; Wang, Y; Zhao, Y; Wu, L-L; Hu, J-J; Li, B; Chen, S-J; Yan, C; Zhao, W-L

2015-01-01

Cancer cells have distinct metabolomic profile. Metabolic enzymes regulate key oncogenic signaling pathways and have an essential role on tumor progression. Here, serum metabolomic analysis was performed in 45 patients with T-cell lymphoma (TCL) and 50 healthy volunteers. The results showed that dysregulation of choline metabolism occurred in TCL and was related to tumor cell overexpression of choline kinase-α (Chokα). In T-lymphoma cells, pharmacological and molecular silencing of Chokα significantly decreased Ras-GTP activity, AKT and ERK phosphorylation and MYC oncoprotein expression, leading to restoration of choline metabolites and induction of tumor cell apoptosis/necropotosis. In a T-lymphoma xenograft murine model, Chokα inhibitor CK37 remarkably retarded tumor growth, suppressed Ras-AKT/ERK signaling, increased lysophosphatidylcholine levels and induced in situ cell apoptosis/necropotosis. Collectively, as a regulatory gene of aberrant choline metabolism, Chokα possessed oncogenic activity and could be a potential therapeutic target in TCL, as well as other hematological malignancies with interrupted Ras signaling pathways

Mutational, Phylogeny and Evolution Analyses of Salvia Copalyl Diphosphate Synthase

International Nuclear Information System (INIS)

Hao, D. C.; Thimmappa, R. B.; Xiao, P. G.

2016-01-01

The cyclization of geranylgeranyl diphosphate (GGPP) is catalyzed by copalyl diphosphate synthase (CPS), a class II diterpene synthase (diTPS), to form copalyl diphosphate (CPP), which is an essential substrate of a variety of diterpenes in secondary metabolism of angiosperm including Salvia medicinal plants. The protein environment of the N-terminal class II active site stabilizes the carbocation intermediates and maintains the catalytic activity of angiosperm class II diTPS. The virtual modeling and mutagenesis of the class II diTPS of Salvia miltiorrhiza (SmCPS) were accomplished to illuminate the catalytic activity of SmCPS. Terminal truncations and point mutations established the role of the Beta-Gamma domain and Alpha domain, i.e., they facilitate the flexible conformational change of the class II active site after substrate binding. E203 and K238 in the N-ter Gamma domain of SmCPS1 are functional in the substrate binding and conformational transition and might be essential in catalysis. Similar to other CPSs, the ensuing protonation of the GGPP substrate and coordination of the diphosphate group are governed by highly conserved residues in the DxDD motif of SmCPS, e.g., D372 of CPS1. Moreover, F256 and Y505 stabilize the carbocation and control the enzymatic activity during CPP formation. The amino acids of the predicted active sites, despite under purifying selection, vary greatly, corresponding to the functional flexibility of angiosperm CPSs. Molecular phylogeny and evolution analyses suggest early and ongoing evolution of labdane-related diterpenoid metabolism in angiosperm. (author)

Spatial memory and hippocampal plasticity are differentially sensitive to the availability of choline in adulthood as a function of choline supply in utero.

Science.gov (United States)

Wong-Goodrich, Sarah J E; Glenn, Melissa J; Mellott, Tiffany J; Blusztajn, Jan K; Meck, Warren H; Williams, Christina L

2008-10-27

Altered dietary choline availability early in life leads to persistent changes in spatial memory and hippocampal plasticity in adulthood. Developmental programming by early choline nutrition may determine the range of adult choline intake that is optimal for the types of neural plasticity involved in cognitive function. To test this, male Sprague-Dawley rats were exposed to a choline chloride deficient (DEF), sufficient (CON), or supplemented (SUP) diet during embryonic days 12-17 and then returned to a control diet (1.1 g choline chloride/kg). At 70 days of age, we found that DEF and SUP rats required fewer choices to locate 8 baited arms of a 12-arm radial maze than CON rats. When switched to a choline-deficient diet (0 g/kg), SUP rats showed impaired performance while CON and DEF rats were unaffected. In contrast, when switched to a choline-supplemented diet (5.0 g/kg), DEF rats' performance was significantly impaired while CON and SUP rats were less affected. These changes in performance were reversible when the rats were switched back to a control diet. In a second experiment, DEF, CON, and SUP rats were either maintained on a control diet, or the choline-supplemented diet. After 12 weeks, DEF rats were significantly impaired by choline supplementation on a matching-to-place water-maze task, which was also accompanied by a decrease in dentate cell proliferation in DEF rats only. IGF-1 levels were elevated by both prenatal and adult choline supplementation. Taken together, these findings suggest that the in utero availability of an essential nutrient, choline, causes differential behavioral and neuroplastic sensitivity to the adult choline supply.

Neuroprotective Actions of Dietary Choline

Directory of Open Access Journals (Sweden)

Jan Krzysztof Blusztajn

2017-07-01

Full Text Available Choline is an essential nutrient for humans. It is a precursor of membrane phospholipids (e.g., phosphatidylcholine (PC, the neurotransmitter acetylcholine, and via betaine, the methyl group donor S-adenosylmethionine. High choline intake during gestation and early postnatal development in rat and mouse models improves cognitive function in adulthood, prevents age-related memory decline, and protects the brain from the neuropathological changes associated with Alzheimer’s disease (AD, and neurological damage associated with epilepsy, fetal alcohol syndrome, and inherited conditions such as Down and Rett syndromes. These effects of choline are correlated with modifications in histone and DNA methylation in brain, and with alterations in the expression of genes that encode proteins important for learning and memory processing, suggesting a possible epigenomic mechanism of action. Dietary choline intake in the adult may also influence cognitive function via an effect on PC containing eicosapentaenoic and docosahexaenoic acids; polyunsaturated species of PC whose levels are reduced in brains from AD patients, and is associated with higher memory performance, and resistance to cognitive decline.

A Yeast Mutant Deleted of GPH1 Bears Defects in Lipid Metabolism.

Directory of Open Access Journals (Sweden)

Martina Gsell

Full Text Available In a previous study we demonstrated up-regulation of the yeast GPH1 gene under conditions of phosphatidylethanolamine (PE depletion caused by deletion of the mitochondrial (M phosphatidylserine decarboxylase 1 (PSD1 (Gsell et al., 2013, PLoS One. 8(10:e77380. doi: 10.1371/journal.pone.0077380. Gph1p has originally been identified as a glycogen phosphorylase catalyzing degradation of glycogen to glucose in the stationary growth phase of the yeast. Here we show that deletion of this gene also causes decreased levels of phosphatidylcholine (PC, triacylglycerols and steryl esters. Depletion of the two non-polar lipids in a Δgph1 strain leads to lack of lipid droplets, and decrease of the PC level results in instability of the plasma membrane. In vivo labeling experiments revealed that formation of PC via both pathways of biosynthesis, the cytidine diphosphate (CDP-choline and the methylation route, is negatively affected by a Δgph1 mutation, although expression of genes involved is not down regulated. Altogether, Gph1p besides its function as a glycogen mobilizing enzyme appears to play a regulatory role in yeast lipid metabolism.

Relationship Between Organophosphate Toxicity and Choline Metabolism

Science.gov (United States)

1986-06-06

Results from studies on the actions of the organophosphates on the central nervus system have suggested that these compounds, through an action on...Grganophosphates alter the disposition and metabolism of choline and choline-containing compounds in the nervous system , the relationshi ý of these changes to...mechanisms regulating the metabolism of choline, as well as the specific interactions of the organophospha:es with biochemical systems , may differ

Choline Theft-An Inside Job.

Science.gov (United States)

Mora-Ortiz, Marina; Claus, Sandrine Paule

2017-09-13

Choline is a crucial methyl donor necessary for epigenetic regulation. In this issue of Cell Host & Microbe, Romano et al. (2017) demonstrate that choline-utilizing gut bacteria compete with their host for this essential resource, calling for a systematic consideration of gut microbial composition for personalized diet recommendations. Copyright © 2017. Published by Elsevier Inc.

Enzymatic conformational fluctuations along the reaction coordinate of cytidine deaminase

OpenAIRE

Noonan, Ryan C.; Carter, Charles W.; Bagdassarian, Carey K.

2002-01-01

Analysis of the crystal structures for cytidine deaminase complexed with substrate analog 3-deazacytidine, transition-state analog zebularine 3,4-hydrate, and product uridine establishes significant changes in the magnitude of atomic-scale fluctuations along the (approximate) reaction coordinate of this enzyme. Differences in fluctuations between the substrate analog complex, transition-state analog complex, and product complex are monitored via changes in corresponding crystallographic tempe...

Biocompatible choline based ionic salts: Solubility in short-chain alcohols

International Nuclear Information System (INIS)

Lopes, Joana M.; Paninho, Ana B.; Môlho, Marta F.; Nunes, Ana V.M.; Rocha, Angelo; Lourenço, Nuno M.T.; Najdanovic-Visak, Vesna

2013-01-01

Highlights: • Biocompatible ionic liquids based on choline esters were synthesized in this work. • Solubility of choline and choline esters based ionic salt in alcohols were measured. • Activity coefficients were calculated. • Experimental data were correlated by means of the semi-empirical Grant equation. -- Abstract: In this work, we report data on solubility of choline chloride and choline acetate in short-chain linear alcohols (ethanol, 1-propanol and 1-butanol) at various temperatures. Furthermore, we synthesize two choline derivatives: hydrogen choline chloride glutarate ([CholGlut][Cl]) and hydrogen choline chloride succinate ([CholSucc][Cl]). Their characterization and solubility in short-chain alcohols as a function of temperature are also included. Activity coefficients were calculated and their comparisons with ideal solutions were discussed. The experimental data were correlated successfully by means of the semi-empirical Grant equation

Identification and Characterization of the Nuclear Isoform of Drosophila melanogaster CTP:Phosphocholine Cytidylyltransferase

Science.gov (United States)

CTP:phosphocholine cytidylyltransferase (CCT) catalyzes the conversion of phosphocholine and cytidine 5'-triphosphate (CTP) to CDP-choline for the eventual synthesis of phosphatidylcholine (PC). The enzyme is regulated by reversible association with cellular membranes, with the rate of catalysis in...

A terbium(III)-organic framework for highly selective sensing of cytidine triphosphate.

Science.gov (United States)

Zhao, Xi Juan; He, Rong Xing; Li, Yuan Fang

2012-11-21

Highly selective sensing of cytidine triphosphate (CTP) against other triphosphate nucleosides including ATP, GTP and UTP is successfully achieved with a luminescent terbium(III)-organic framework (TbOF) of [Tb(2)(2,3-pzdc)(2)(ox)(H(2)O)(2)](n) (2,3-pzdc(2-) = 2,3-pyrazinedicarboxylate, ox(2-) = oxalate).

Structure of trihydrated rare-earth acid diphosphates LnHP2O7·3H2O (Ln=La, Er)

International Nuclear Information System (INIS)

Ben Moussa, S.; Ventemillas, S.; Cabeza, A.; Gutierrez-Puebla, E.; Sanz, J.

2004-01-01

In trihydrated lanthanum acid-diphosphates LnHP 2 O 7 ·3H 2 O, prepared from acid LnCl 3 and Na 4 P 2 O 7 solutions (pH=1), two crystal forms were obtained. Layered structures of two representative members of this family have been determined by single-crystal X-ray diffraction (XRD) technique. In the case of orthorhombic LaHP 2 O 7 ·3H 2 O (type I), lanthanum cations are ninefold coordinated and diphosphate groups adopt a staggered (alternated) configuration. In the case of triclinic ErHP 2 O 7 ·3H 2 O (type II), erbium cations are eightfold coordinated and diphosphate groups adopt an eclipsed configuration. In agreement with Infrared (IR) spectroscopic data, a bended configuration for diphosphate groups has been deduced. In both structures, one-dimensional chains of edge-sharing rare-earth polyhedra are linked together by diphosphate groups to form the phosphate layers. In both diphosphates, PO 4 and HPO 4 environments have been identified by 31 P MAS-NMR technique. In the two compounds, OH groups of HPO 4 tetrahedra point out of diphosphate planes interacting with adjacent layers. In La-diphosphate, the interaction between HPO 4 groups and water molecules of adjacent layers is favored; however, in Er-diphosphate, the interaction between phosphate acid groups of contiguous layers is produced. Based on structural information deduced, differences detected in IR and NMR spectra of two disphosphates are discussed

Modification of zirconium diphosphate with salicylic acid and its effect on the uranium (Vi) sorption

International Nuclear Information System (INIS)

Almazan T, M. G.; Garcia G, N.; Simoni, E.

2014-10-01

The surface of zirconium diphosphate (ZrP 2 O 7 ) was modified with salicylic acid and its effect was evaluated on the uranium (Vi) sorption. The modified surface of the material was analyzed with different analytical techniques among which are included the atomic force microscopy, scanning electron microscopy and X-ray photoelectron spectroscopy. This analysis allowed showing that the salicylic acid is being held on the surface of the zirconium diphosphate. The reactivity of modified zirconium diphosphate compared with uranium (Vi) was investigated using the classical method of batch sorption. The analysis of sorption isotherms shows that the salicylic acid has an important effect in the uranium (Vi) sorption. According to the study conducted, the interaction among the uranium (Vi) and the surface of zirconium diphosphate modified with the salicylic acid most likely leads to the complexes formation of binary (U(Vi)/ZrP 2 O 7 ) and ternary (U(Vi)/salicylate/ZrP 2 O 7 ) surface. (Author)

Cytidine triphosphate synthase activity and mRNA expression in normal human blood cells

NARCIS (Netherlands)

Verschuur, A. C.; van Gennip, A. H.; Muller, E. J.; Voûte, P. A.; Vreken, P.; van Kuilenburg, A. B.

1999-01-01

Cytidine triphosphate (CTP) synthase is one of the key enzymes in pyrimidine nucleotide anabolic pathways. The activity of this enzyme is elevated in various malignancies including acute lymphocytic leukemia (ALL). In this study we investigated the activity of CTP synthase in various human blood

Spatial memory and hippocampal plasticity are differentially sensitive to the availability of choline in adulthood as a function of choline supply in utero

OpenAIRE

Wong-Goodrich, Sarah J.E.; Glenn, Melissa J.; Mellott, Tiffany J.; Blusztajn, Jan K.; Meck, Warren H.; Williams, Christina L.

2008-01-01

Altered dietary choline availability early in life leads to persistent changes in spatial memory and hippocampal plasticity in adulthood. Developmental programming by early choline nutrition may determine the range of adult choline intake that is optimal for the types of neural plasticity involved in cognitive function. To test this, male Sprague-Dawley rats were exposed to a choline chloride deficient (DEF), sufficient (CON), or supplemented (SUP) diet during embryonic days 12-17 and then re...

Recent Advances in the Development of Mammalian Geranylgeranyl Diphosphate Synthase Inhibitors

Directory of Open Access Journals (Sweden)

Staci L. Haney

2017-05-01

Full Text Available The enzyme geranylgeranyl diphosphate synthase (GGDPS catalyzes the synthesis of the 20-carbon isoprenoid geranylgeranyl diphosphate (GGPP. GGPP is the isoprenoid donor for protein geranylgeranylation reactions catalyzed by the enzymes geranylgeranyl transferase (GGTase I and II. Inhibitors of GGDPS result in diminution of protein geranylgeranylation through depletion of cellular GGPP levels, and there has been interest in GGDPS inhibitors as potential anti-cancer agents. Here we discuss recent advances in the development of GGDPS inhibitors, including insights gained by structure-function relationships, and review the preclinical data that support the continued development of this novel class of drugs.

21 CFR 182.8252 - Choline chloride.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Choline chloride. 182.8252 Section 182.8252 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR... chloride. (a) Product. Choline chloride. (b) Conditions of use. This substance is generally recognized as...

Silver vanadium diphosphate Ag2VP2O8: Electrochemistry and characterization of reduced material providing mechanistic insights

International Nuclear Information System (INIS)

Takeuchi, Esther S.; Lee, Chia-Ying; Cheng, Po-Jen; Menard, Melissa C.; Marschilok, Amy C.; Takeuchi, Kenneth J.

2013-01-01

Silver vanadium phosphorous oxides (Ag w V x P y O z ) are notable battery cathode materials due to their high energy density and demonstrated ability to form in-situ Ag metal nanostructured electrically conductive networks within the cathode. While analogous silver vanadium diphosphate materials have been prepared, electrochemical evaluations of these diphosphate based materials have been limited. We report here the first electrochemical study of a silver vanadium diphosphate, Ag 2 VP 2 O 8 , where the structural differences associated with phosphorous oxides versus diphosphates profoundly affect the associated electrochemistry. Reminiscent of Ag 2 VO 2 PO 4 reduction, in-situ formation of silver metal nanoparticles was observed with reduction of Ag 2 VP 2 O 8 . However, counter to Ag 2 VO 2 PO 4 reduction, Ag 2 VP 2 O 8 demonstrates a significant decrease in conductivity upon continued electrochemical reduction. Structural analysis contrasting the crystallography of the parent Ag 2 VP 2 O 8 with that of the proposed Li 2 VP 2 O 8 reduction product is employed to gain insight into the observed electrochemical reduction behavior, where the structural rigidity associated with the diphosphate anion may be associated with the observed particle fracturing upon deep electrochemical reduction. Further, the diphosphate anion structure may be associated with the high thermal stability of the partially reduced Ag 2 VP 2 O 8 materials, which bodes well for enhanced safety of batteries incorporating this material. - Graphical abstract: Structure and galvanostatic intermittent titration-type test data for silver vanadium diphosphate, Ag 2 VP 2 O 8 . Highlights: ► First electrochemical study of a silver vanadium diphosphate, Ag 2 VP 2 O 8 . ► In-situ formation of Ag 0 nanoparticles was observed upon electrochemical reduction. ► Structural analysis used to provide insight of the electrochemical behavior

Dependence of the product chain-length on detergents for long-chain E-polyprenyl diphosphate synthases

Science.gov (United States)

Pan, Jian-Jung; Ramamoorthy, Gurusankar; Poulter, C. Dale

2013-01-01

Long-chain E-polyprenyl diphosphate synthases (E-PDS) catalyze repetitive addition of isopentenyl diphosphate (IPP) to the growing prenyl chain of an allylic diphosphate. The polyprenyl diphosphate products are required for the biosynthesis of ubiquinones and menaquinones required for electron transport during oxidative phosphorylation to generate ATP. In vitro, the long-chain PDSs require addition of phospholipids or detergents to the assay buffer to enhance product release and maintain efficient turnover. During preliminary assays of product chain-length with anionic, zwitterionic, and non-ionic detergents, we discovered considerable variability. Examination of a series of non-ionic PEG detergents with several long-chain E-PDSs from different organisms revealed that in vitro incubations with nonaethylene glycol monododecyl ether or Triton X-100 typically gave chain lengths that corresponded to those of the isoprenoid moieties in respiratory quinones synthesized in vivo. In contrast incubations in buffer with n-butanol, CHAPS, DMSO, n-octyl-β-glucopyranoside, or β-cyclodextrin or in buffer without detergent typically proceeded more slowly and gave a broad range of chain lengths. PMID:23802587

New approaches to the synthesis of diclofenac choline

Directory of Open Access Journals (Sweden)

Elżbieta Dąbrowska-Maś

2017-07-01

Full Text Available The process described herein proceeds to obtaining diclofenac choline from choline bicarbonate and diclofenac acid in mild conditions, using non-toxic solvent, with the same impurity profile deriving from diclofenac particle as for diclofenac sodium EP. The substance is also substantially free from impurities deriving from choline and free from inorganic by-products, what means that the quality may be accepted for use as an active substance in medicine.

Choline-mediated modulation of hippocampal sharp wave-ripple complexes in vitro.

Science.gov (United States)

Fischer, Viktoria; Both, Martin; Draguhn, Andreas; Egorov, Alexei V

2014-06-01

The cholinergic system is critically involved in the modulation of cognitive functions, including learning and memory. Acetylcholine acts through muscarinic (mAChRs) and nicotinic receptors (nAChRs), which are both abundantly expressed in the hippocampus. Previous evidence indicates that choline, the precursor and degradation product of Acetylcholine, can itself activate nAChRs and thereby affects intrinsic and synaptic neuronal functions. Here, we asked whether the cellular actions of choline directly affect hippocampal network activity. Using mouse hippocampal slices we found that choline efficiently suppresses spontaneously occurring sharp wave-ripple complexes (SPW-R) and can induce gamma oscillations. In addition, choline reduces synaptic transmission between hippocampal subfields CA3 and CA1. Surprisingly, these effects are mediated by activation of both mAChRs and α7-containing nAChRs. Most nicotinic effects became only apparent after local, fast application of choline, indicating rapid desensitization kinetics of nAChRs. Effects were still present following block of choline uptake and are, therefore, likely because of direct actions of choline at the respective receptors. Together, choline turns out to be a potent regulator of patterned network activity within the hippocampus. These actions may be of importance for understanding state transitions in normal and pathologically altered neuronal networks. In this study we asked whether choline, the precursor and degradation product of acetylcholine, directly affects hippocampal network activity. Using mouse hippocampal slices we found that choline efficiently suppresses spontaneously occurring sharp wave-ripple complexes (SPW-R). In addition, choline reduces synaptic transmission between hippocampal subfields. These effects are mediated by direct activation of muscarinic as well as nicotinic cholinergic pathways. Together, choline turns out to be a potent regulator of patterned activity within hippocampal

Of the Nine Cytidine Deaminase-Like Genes in Arabidopsis, Eight Are Pseudogenes and Only One Is Required to Maintain Pyrimidine Homeostasis in Vivo.

Science.gov (United States)

Chen, Mingjia; Herde, Marco; Witte, Claus-Peter

2016-06-01

CYTIDINE DEAMINASE (CDA) catalyzes the deamination of cytidine to uridine and ammonia in the catabolic route of C nucleotides. The Arabidopsis (Arabidopsis thaliana) CDA gene family comprises nine members, one of which (AtCDA) was shown previously in vitro to encode an active CDA. A possible role in C-to-U RNA editing or in antiviral defense has been discussed for other members. A comprehensive bioinformatic analysis of plant CDA sequences, combined with biochemical functionality tests, strongly suggests that all Arabidopsis CDA family members except AtCDA are pseudogenes and that most plants only require a single CDA gene. Soybean (Glycine max) possesses three CDA genes, but only two encode functional enzymes and just one has very high catalytic efficiency. AtCDA and soybean CDAs are located in the cytosol. The functionality of AtCDA in vivo was demonstrated with loss-of-function mutants accumulating high amounts of cytidine but also CMP, cytosine, and some uridine in seeds. Cytidine hydrolysis in cda mutants is likely caused by NUCLEOSIDE HYDROLASE1 (NSH1) because cytosine accumulation is strongly reduced in a cda nsh1 double mutant. Altered responses of the cda mutants to fluorocytidine and fluorouridine indicate that a dual specific nucleoside kinase is involved in cytidine as well as uridine salvage. CDA mutants display a reduction in rosette size and have fewer leaves compared with the wild type, which is probably not caused by defective pyrimidine catabolism but by the accumulation of pyrimidine catabolism intermediates reaching toxic concentrations. © 2016 American Society of Plant Biologists. All Rights Reserved.

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

DEFF Research Database (Denmark)

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

1996-01-01

The three conserved aspartic acid residues of the 5-phospho-d-ribosyl a-1-diphosphate binding site (213-GRDCVLVDDMIDTGGT-228) of Escherichia coli phosphoribosyl diphosphate synthetase were studied by analysis of the mutant enzymes D220E, D220F, D221A, D224A, and D224S. The mutant enzymes showed...... enzymes were dependent on the metal ion present, suggesting a function of the investigated aspartic acid residues both in the binding of ribose 5-phosphate, possibly via a divalent metal ion, and in the interaction with a divalent metal ion during catalysis....

{sup 18}F-Choline, {sup 11}C-choline and {sup 11}C-acetate PET/CT: comparative analysis for imaging prostate cancer patients

Energy Technology Data Exchange (ETDEWEB)

Brogsitter, Claudia; Zoephel, Klaus; Kotzerke, Joerg [Carl Gustav Carus Medical School, University of Dresden, Department of Nuclear Medicine, Dresden (Germany)

2013-07-15

Prostate cancer (PCA) is the second most common tumour in men worldwide. Whereas prostate specific antigen (PSA) is an established biochemical marker, the optimal imaging method for all clinical scenarios has not yet been found. With the rising number of PET centres there is an increasing availability and use of {sup 18}F-/{sup 11}C-choline or {sup 11}C-acetate for staging of PCA. However, to date no final conclusion has been reached as to whether acetate or choline tracers should be preferred. In this review we provide an overview of the performance of choline and acetate PET for staging the primary and recurrent disease and lymph nodes in PCA, based on the literature of the last 10 years. Although predominantly choline has been used rather than acetate, both tracers performed in a similar manner in published studies. Choline as well as acetate have insufficient diagnostic accuracy for the staging of the primary tumour, due to a minimum detectable tumour size of 5 mm and inability to differentiate PCA from benign prostate hyperplasia, chronic prostatitis and high-grade intraepithelial neoplasia. Regarding lymph node staging, choline tracers have demonstrated a high specificity. Unfortunately, the sensitivity is only moderate. For staging recurrent disease, sensitivity depends on the level of serum PSA (PSA should be >2 ng/ml). This applies to both choline and acetate. However, despite these limitations, a significant number of patients with recurrent disease can benefit from PET imaging by a change in treatment planning. (orig.)

Co-expression of peppermint geranyl diphosphate synthase small subunit enhances monoterpene production in transgenic tobacco plants.

Science.gov (United States)

Yin, Jun-Lin; Wong, Woon-Seng; Jang, In-Cheol; Chua, Nam-Hai

2017-02-01

Monoterpenes are important for plant survival and useful to humans. In addition to their function in plant defense, monoterpenes are also used as flavors, fragrances and medicines. Several metabolic engineering strategies have been explored to produce monoterpene in tobacco but only trace amounts of monoterpenes have been detected. We investigated the effects of Solanum lycopersicum 1-deoxy-d-xylulose-5-phosphate synthase (SlDXS), Arabidopsis thaliana geranyl diphosphate synthase 1 (AtGPS) and Mentha × piperita geranyl diphosphate synthase small subunit (MpGPS.SSU) on production of monoterpene and geranylgeranyl diphosphate (GGPP) diversities, and plant morphology by transient expression in Nicotiana benthamiana and overexpression in transgenic Nicotiana tabacum. We showed that MpGPS.SSU could enhance the production of various monoterpenes such as (-)-limonene, (-)-linalool, (-)-α-pinene/β-pinene or myrcene, in transgenic tobacco by elevating geranyl diphosphate synthase (GPS) activity. In addition, overexpression of MpGPS.SSU in tobacco caused early flowering phenotype and increased shoot branching by elevating contents of GA 3 and cytokinins due to upregulated transcript levels of several plastidic 2-C-methyl-d-erythritol-4-phosphate (MEP) pathway genes, geranylgeranyl diphosphate synthases 3 (GGPPS3) and GGPPS4. Our method would allow the identification of new monoterpene synthase genes using transient expression in N. benthamiana and the improvement of monoterpene production in transgenic tobacco plants. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

Rumen-protected choline: A significance effect on dairy cattle nutrition.

Science.gov (United States)

Jayaprakash, G; Sathiyabarathi, M; Robert, M Arokia; Tamilmani, T

2016-08-01

Choline is a vitamin-like substance it has multi-function in animal production, reproduction, and health. The transition period is most crucial stage in lactation cycle of dairy cows due to its association with negative hormonal and energy balances. Unfortunately, unprotected choline easily degrades in the rumen; therefore, choline added to the diet in a rumen-protected form. The use of rumen-protected choline (RPC) is a preventive measurement for the fatty liver syndrome and ketosis; may improve milk production as well as milk composition and reproduction parameters. This review summarizes the effectiveness of RPC on animal production, health, and reproduction.

Anaerobic choline metabolism in microcompartments promotes growth and swarming of Proteus mirabilis.

Science.gov (United States)

Jameson, Eleanor; Fu, Tiantian; Brown, Ian R; Paszkiewicz, Konrad; Purdy, Kevin J; Frank, Stefanie; Chen, Yin

2016-09-01

Gammaproteobacteria are important gut microbes but only persist at low levels in the healthy gut. The ecology of Gammaproteobacteria in the gut environment is poorly understood. Here, we demonstrate that choline is an important growth substrate for representatives of Gammaproteobacteria. Using Proteus mirabilis as a model, we investigate the role of choline metabolism and demonstrate that the cutC gene, encoding a choline-trimethylamine lyase, is essential for choline degradation to trimethylamine by targeted mutagenesis of cutC and subsequent complementation experiments. Proteus mirabilis can rapidly utilize choline to enhance growth rate and cell yield in broth culture. Importantly, choline also enhances swarming-associated colony expansion of P. mirabilis under anaerobic conditions on a solid surface. Comparative transcriptomics demonstrated that choline not only induces choline-trimethylamine lyase but also genes encoding shell proteins for the formation of bacterial microcompartments. Subsequent analyses by transmission electron microscopy confirmed the presence of such novel microcompartments in cells cultivated in liquid broth and hyper-flagellated swarmer cells from solid medium. Together, our study reveals choline metabolism as an adaptation strategy for P. mirabilis and contributes to better understand the ecology of this bacterium in health and disease. © 2015 The Authors. Environmental Microbiology published by Society for Applied Microbiology and John Wiley & Sons Ltd.

21 CFR 172.370 - Iron-choline citrate complex.

Science.gov (United States)

2010-04-01

....370 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Special Dietary and Nutritional Additives § 172.370 Iron-choline citrate complex. Iron-choline...

Nutrition in pregnancy: the argument for including a source of choline

OpenAIRE

Zeisel, Steven H

2013-01-01

Steven H Zeisel Nutrition Research Institute at Kannapolis, Department of Nutrition, University of North Carolina at Chapel Hill, Kannapolis, NC, USA Abstract: Women, during pregnancy and lactation, should eat foods that contain adequate amounts of choline. A mother delivers large amounts of choline across the placenta to the fetus, and after birth she delivers large amounts of choline in milk to the infant; this greatly increases the demand on the choline stores of the mother. Adequate inta...

Choline Alleviates Parenteral Nutrition-Associated Duodenal Motility Disorder in Infant Rats.

Science.gov (United States)

Zhu, Jie; Wu, Yang; Guo, Yonggao; Tang, Qingya; Lu, Ting; Cai, Wei; Huang, Haiyan

2016-09-01

Parenteral nutrition (PN) has been found to influence duodenal motility in animals. Choline is an essential nutrient, and its deficiency is related to PN-associated organ diseases. Therefore, this study was aimed to investigate the role of choline supplementation in an infant rat model of PN-associated duodenal motility disorder. Three-week-old Sprague-Dawley male rats were fed chow and water (controls), PN solution (PN), or PN plus intravenous choline (600 mg/kg) (PN + choline). Rats underwent jugular vein cannulation for infusion of PN solution or 0.9% saline (controls) for 7 days. Duodenal oxidative stress status, concentrations of plasma choline, phosphocholine, and betaine and serum tumor necrosis factor (TNF)-α were assayed. The messenger RNA (mRNA) and protein expression of c-Kit proto-oncogene protein (c-Kit) and membrane-bound stem cell factor (mSCF) together with the electrophysiological features of slow waves in the duodenum were also evaluated. Rats on PN showed increased reactive oxygen species; decreased total antioxidant capacity in the duodenum; reduced plasma choline, phosphocholine, and betaine; and enhanced serum TNF-α concentrations, which were reversed by choline intervention. In addition, PN reduced mRNA and protein expression of mSCF and c-Kit, which were inversed under choline administration. Moreover, choline attenuated depolarized resting membrane potential and declined the frequency and amplitude of slow waves in duodenal smooth muscles of infant rats induced by PN, respectively. The addition of choline to PN may alleviate the progression of duodenal motor disorder through protecting smooth muscle cells from injury, promoting mSCF/c-Kit signaling, and attenuating impairment of interstitial cells of Cajal in the duodenum during PN feeding. © 2015 American Society for Parenteral and Enteral Nutrition.

Poly(adenosine 5'-diphosphate) ribose polymerase activation as a cause of metabolic dysfunction in critical illness.

Science.gov (United States)

Liaudet, Lucas

2002-03-01

Poly(adenosine 5'-diphosphate) ribose polymerase is a nuclear enzyme activated in response to genotoxic stress induced by a variety of DNA damaging agents. Several oxygen and nitrogen-centered free radicals, notably peroxynitrite, are strong inducers of DNA damage and poly(adenosine 5'-diphosphate) ribose polymerase activation in vitro and in vivo. Activation of this nuclear enzyme depletes the intracellular stores of its substrate nicotinamide adenine dinucleotide, slowing the rate of glycolysis, mitochondrial electron transport and adenosine triphosphate formation. This process triggers a severe energetic crisis within the cell, leading to acute cell dysfunction and cell necrosis. Poly(adenosine 5'-diphosphate) ribose polymerase also plays an important role in the regulation of inflammatory cascades, through a functional association with various transcription factors and transcription co-activators. Recent works identified this enzyme as a critical mediator of cellular metabolic dysfunction, inflammatory injury, and organ damage in conditions associated with overwhelming oxidative stress, including systemic inflammation, circulatory shock, and ischemia-reperfusion. Accordingly, pharmacological inhibitors of poly(adenosine 5'-diphosphate) ribose polymerase protect against cell death and tissue injury in such conditions, and may therefore represent novel therapeutic tools to limit multiple organ damage and dysfunction in critically ill patients.

The association constant of 5',8-cyclo-2'-deoxyguanosine with cytidine

Directory of Open Access Journals (Sweden)

Amedeo eCapobianco

2015-03-01

Full Text Available The association of 5',8-cyclo-2'-deoxyguanosine (cdG, a DNA tandem lesion, with its complementary base cytosine has been studied by voltammetry and NMR in chloroform, using properly silylated derivatives of the two nucleobases for increasing their solubilities. Both voltammetric data and NMR titrations indicated that the Watson-Crick complex of cytidine with cdG is weaker than that with guanosine, the difference being approximately of one order of magnitude between the two association constants.

Multimodal elucidation of choline metabolism in a murine glioma model using magnetic resonance spectroscopy and 11C-choline positron emission tomography

NARCIS (Netherlands)

Wehrl, H.F.; Schwab, J.; Hasenbach, K.; Reischl, G.; Tabatabai, G.; Quintanilla-Martinez, L.; Jiru, F.; Chughtai, K; Kiss, A.; Cay, F.; Bukala, D.; Heeren, R.M.A.; Pichler, B.J.; Sauter, A.W.

2013-01-01

The metabolites, transporters, and enzymes involved in choline metabolism are regarded as biomarkers for disease progression in a variety of cancers, but their in vivo detection is not ideal. Both magnetic resonance spectroscopy [MRS using chemical shift imaging (CSI) total choline (tCho)] and

Choline transport in the isolated rabbit corneal epithelium

International Nuclear Information System (INIS)

Faust, R.L.

1988-01-01

In the present study, isolated epithelial sheets were obtained by performing two sequential anterior keratectomies, three weeks apart, on rabbit corneas. Light microscopy of the isolated sheets revealed a multilayered epithelium with an intact basal cell layer without contamination from other cell types. The accumulation of [ 3 H]choline into the epithelial sheets was studied at substrate concentrations varying from 1 to 100 μMoles with and without the addition of specific metabolic and stereochemical inhibitors. Accumulation of [ 3 H]choline into these sheets was saturable. Kinetic analysis, performed by estimation from double-reciprocal plots, revealed a single component system with a K m of 24.9 μM. The metabolic inhibitors potassium cyanide and ouabain showed no effect on the uptake of [ 3 H]choline; however, the stereochemical inhibitor hemicholinium-3 significantly reduced the accumulation of radiolabel at both high and low substrate concentrations. The results suggest a non-energy dependent yet a highly specific transport system for the accumulation of choline into the rabbit epithelium

ESR study of irradiated single crystals of the cocrystalline complex of cytidine: Salicylic acid

International Nuclear Information System (INIS)

Close, D.M.; Sagstuen, E.

1983-01-01

Irradiation at 77 K of single crystals of the 1:1 complex of cytidine and salicylic acid produces a phenoxyl radical formed by oxidation of the salicylic acid. Anisotropic hyperfine coupling tensors have been determined for this radical which are associated with the para and ortho hydrogens. No cytidine oxidation products (alkoxy or hydroxyalkyl radicals) were observed at 77 K. Following the decay of the phenoxyl radical at room temperature, four radicals were detected. These include the cytosine 5--yl and 6--yl radicals, formed by H addition to the cytosine ring, and an anisotropic doublet. By UV irradiation at room temperature, it is possible to convert a significant fraction of 6-yl radicals into 5-yl radicals. Hyperfine coupling and g tensors determined for the anisotropic doublet indicate that this radical is formed in the C/sub 1'/-C/sub 2'/ region of the sugar moiety. These results indicate a shift in radiation damage away from the salicylic acid upon warming, and show that the radiation chemistry of the cocrystalline complex is different from that of the isolated bases

Phosphorylation of the Yeast Choline Kinase by Protein Kinase C

Science.gov (United States)

Choi, Mal-Gi; Kurnov, Vladlen; Kersting, Michael C.; Sreenivas, Avula; Carman, George M.

2005-01-01

The Saccharomyces cerevisiae CKI1-encoded choline kinase catalyzes the committed step in phosphatidylcholine synthesis via the Kennedy pathway. The enzyme is phosphorylated on multiple serine residues, and some of this phosphorylation is mediated by protein kinase A. In this work, we examined the hypothesis that choline kinase is also phosphorylated by protein kinase C. Using choline kinase as a substrate, protein kinase C activity was dose- and time-dependent, and dependent on the concentrations of choline kinase (Km = 27 μg/ml) and ATP (Km = 15 μM). This phosphorylation, which occurred on a serine residue, was accompanied by a 1.6-fold stimulation of choline kinase activity. The synthetic peptide SRSSS25QRRHS (Vmax/Km = 17.5 mM-1 μmol min-1 mg-1) that contains the protein kinase C motif for Ser25 was a substrate for protein kinase C. A Ser25 to Ala (S25A) mutation in choline kinase resulted in a 60% decrease in protein kinase C phosphorylation of the enzyme. Phosphopeptide mapping analysis of the S25A mutant enzyme confirmed that Ser25 was a protein kinase C target site. In vivo, the S25A mutation correlated with a decrease (55%) in phosphatidylcholine synthesis via the Kennedy pathway whereas an S25D phosphorylation site mimic correlated with an increase (44%) in phosphatidylcholine synthesis. Whereas the S25A (protein kinase C site) mutation did not affect the phosphorylation of choline kinase by protein kinase A, the S30A (protein kinase A site) mutation caused a 46% reduction in enzyme phosphorylation by protein kinase C. A choline kinase synthetic peptide (SQRRHS30LTRQ) containing Ser30 was a substrate (Vmax/Km = 3.0 mM−1 μmol min−1 mg−1) for protein kinase C. Comparison of phosphopeptide maps of the wild type and S30A mutant choline kinase enzymes phosphorylated by protein kinase C confirmed that Ser30 was also a target site for protein kinase C. PMID:15919656

Autoradiographic imaging of phosphoinositide turnover in the brain

International Nuclear Information System (INIS)

Hwang, P.M.; Bredt, D.S.; Snyder, S.H.

1990-01-01

With [ 3 H]cytidine as a precursor, phosphoinositide turnover can be localized in brain slices by selective autoradiography of the product [ 3 H]cytidine diphosphate diacylglycerol, which is membrane-bound. In the cerebellum, glutamatergic stimulation elicits an increase of phosphoinositide turnover only in Purkinje cells and the molecular layer. In the hippocampus, both glutamatergic and muscarinic cholinergic stimulation increase phosphoinositide turnover, but with distinct localizations. Cholinergic stimulation affects CA1, CA3, CA4, and subiculum, whereas glutamatergic effects are restricted to the subiculum and CA3. Imaging phosphoinositide turnover in brain slices, which are amenable to electrophysiologic studies, will permit a dynamic localized analysis of regulation of this second messenger in response to synaptic stimulation of specific neuronal pathways

Localization of phosphatidylinositol signaling components in rat taste cells: Role in bitter taste transduction

International Nuclear Information System (INIS)

Hwang, P.M.; Verma, A.; Bredt, D.S.; Snyder, S.H.

1990-01-01

To assess the role of phosphatidylinositol turnover in taste transduction we have visualized, in rat tongue, ATP-dependent endoplasmic reticular accumulation of 45 Ca 2+ , inositol 1,4,5-trisphosphate receptor binding sites, and phosphatidylinositol turnover monitored by autoradiography of [ 3 H]cytidine diphosphate diacylglycerol formed from [ 3 H]cytidine. Accumulated 45 Ca 2+ , inositol 1,4,5-trisphosphate receptors, and phosphatidylinositol turnover are selectively localized to apical areas of the taste buds of circumvallate papillae, which are associated with bitter taste. Further evidence for a role of phosphatidylinositol turnover in bitter taste is our observation of a rapid, selective increase in mass levels of inositol 1,4,5-trisphosphate elicited by low concentrations of denatonium, a potently bitter tastant

The 1-hydroxy-2-methyl-butenyl 4-diphosphate reductase gene from ...

African Journals Online (AJOL)

The 1-hydroxy-2-methyl-butenyl 4-diphosphate reductase gene from Taxus media: Cloning, characterization and functional identification. Y Sun, M Chen, J Tang, W Liu, C Yang, Y Yang, X Lan, M Hsieh, Z Liao ...

Importance of Choline as Essential Nutrient and Its Role in Prevention of Various Toxicities

Directory of Open Access Journals (Sweden)

Somava Biswas

2015-01-01

Full Text Available Choline is a water-soluble essential nutrient included as a member of the vitamin B12 group owing to its structural similarities with that of the other members of the group. Its roles and functions, however, extend much wider than that of the vitamins with which it is grouped. Choline is vital for maintenance of various key metabolic processes which play a role in the prevention or progression of various health impairments. The occurrence of diseases like neural tube defect (NTD and Alzheimer’s is prevented by the metabolic role of choline. It is also indispensable for mitigation of various forms of toxic contamination. While adequate level of choline in the body is essential, an excess of choline can result in various forms of disorder. To maintain the optimal level of choline in the body can be a challenge. The vital roles played by choline together with the range of contradictions and problems that choline presents make choline an interesting area of study. This paper attempts to summarize and review some recent publications on choline that have opened up new prospect in understanding the multiple role played by choline and in throwing light on the role played by this wonder essential nutrient in mitigating various forms of toxic contamination.

Formulation and utilization of choline based samples for dissolution dynamic nuclear polarization

DEFF Research Database (Denmark)

Bowen, Sean; Ardenkjær-Larsen, Jan Henrik

2013-01-01

their performance to more traditional sample formulations. Choline yields stable samples with exceptional polarization performance while simultaneously offering the capability to easily remove the choline after dissolution, perform experiments with the hyperpolarized choline, or anything in between....

Inhibition of Coenzyme Qs Accumulation in Engineered Escherichia coli by High Concentration of Farnesyl Diphosphate

OpenAIRE

Samoudi, Mojtaba; Omid Yeganeh, Negar; Shahbani Zahiri, Hossein; Shariati, Parvin; Hajhosseini, Reza

2015-01-01

Background: Coenzyme Q 10 (CoQ 10 ) is an isoprenoid component used widely in nutraceutical industries. Farnesyl diphosphate synthase (FPPS) is a responsible enzyme for biosynthesis of farnesyl diphosphate (FPP), a key precursor for CoQs production. This research involved investigating the effect of FPPS over-expression on CoQs production in engineered CoQ 10 -producing Escherichia coli (E. coli). Methods: Two CoQ 10 -producing strains, as referred to E. coli Ba and E. coli Br, were transform...

Cloning and sequencing of cDNAs specifying a novel class of phosphoribosyl diphosphate synthase in Arabidopsis thaliana

DEFF Research Database (Denmark)

Krath, Britta N.; Eriksen, Tina A.; Poulsen, Tim S.

1999-01-01

cDNAs specifying four active phosphoribosyl diphosphate synthase isozymes were isolated from an Arabidopsis thaliana cDNA library. In contrast to other phosphoribosyl diphosphate synthases the activity of two of the A. thaliana isozymes are independent of Pi. Amino acid sequence comparison and ph...

Evaluation of the PET component of simultaneous [18F]choline PET/MRI in prostate cancer: comparison with [18F]choline PET/CT

International Nuclear Information System (INIS)

Wetter, Axel; Lipponer, Christine; Nensa, Felix; Altenbernd, Jens-Christian; Schlosser, Thomas; Lauenstein, Thomas; Heusch, Philipp; Ruebben, Herbert; Bockisch, Andreas; Poeppel, Thorsten; Nagarajah, James

2014-01-01

The aim of this study was to evaluate the positron emission tomography (PET) component of [ 18 F]choline PET/MRI and compare it with the PET component of [ 18 F]choline PET/CT in patients with histologically proven prostate cancer and suspected recurrent prostate cancer. Thirty-six patients were examined with simultaneous [ 18 F]choline PET/MRI following combined [ 18 F]choline PET/CT. Fifty-eight PET-positive lesions in PET/CT and PET/MRI were evaluated by measuring the maximum and mean standardized uptake values (SUV max and SUV mean ) using volume of interest (VOI) analysis. A scoring system was applied to determine the quality of the PET images of both PET/CT and PET/MRI. Agreement between PET/CT and PET/MRI regarding SUV max and SUV mean was tested using Pearson's product-moment correlation and Bland-Altman analysis. All PET-positive lesions that were visible on PET/CT were also detectable on PET/MRI. The quality of the PET images was comparable in both groups. Median SUV max and SUV mean of all lesions were significantly lower in PET/MRI than in PET/CT (5.2 vs 6.1, p max of PET/CT and PET/MRI (R = 0.86, p mean of PET/CT and PET/MRI (R = 0.81, p max of PET/CT vs PET/MRI and -1.12 to +2.23 between SUV mean of PET/CT vs PET/MRI. PET image quality of PET/MRI was comparable to that of PET/CT. A highly significant correlation between SUV max and SUV mean was found. Both SUV max and SUV mean were significantly lower in [ 18 F]choline PET/MRI than in [ 18 F]choline PET/CT. Differences of SUV max and SUV mean might be caused by different techniques of attenuation correction. Furthermore, differences in biodistribution and biokinetics of [ 18 F]choline between the subsequent examinations and in the respective organ systems have to be taken into account. (orig.)

Density fluctuation in a screened Coulombic colloid dispersion: comparison of the liquid and cubic phases of lipid A-diphosphate

International Nuclear Information System (INIS)

Brown, Helen; Ross, D. Keith; Paradies, Henrich H.

2004-01-01

Light-, small-angle X-ray and neutron scattering measurements of the dynamic structure factor S(Q,t) of strong interacting dispersions of lipid A-diphosphate were recorded and analysed applying existing models of liquid state theory. Lipid A-diphosphate ordering was observed at low volume fractions (phi=2.2x10 -4 ) and at very low ionic strength (I=10 -5 M). Upon increasing the particle number density of lipid A-diphosphate a transformation of the lattices of the colloidal crystals from a BCC lattice (a=36.20 nm) to a FCC lattice (a=57.30 nm) occurred. This strongly suggests a similarity in the preformed liquid structure and the cubic colloidal phase. The fit of both S eff (Q) and the principle peak I p (Q) with the effective particle charge supports of the main conclusions drawn from the SANS experiments and the liquid state theory indicating the presence of long-range order for the dispersions of lipid A-diphosphate

Trypanosoma brucei solanesyl-diphosphate synthase localizes to the mitochondrion

Czech Academy of Sciences Publication Activity Database

Lai, D.-H.; Bontempi, E. J.; Lukeš, Julius

2012-01-01

Roč. 183, č. 2 (2012), s. 189-192 ISSN 0166-6851 R&D Projects: GA ČR(CZ) GAP305/11/2179 Institutional support: RVO:60077344 Keywords : Trypanosoma brucei * Sleeping sickness * Ubiquinone * Solanesyl-diphosphate synthase * Digitonin permeabilization * In situ tagging Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.734, year: 2012 http://www.sciencedirect.com/science/article/pii/S0166685112000539

Functional identification of a Lippia dulcis bornyl diphosphate synthase that contains a duplicated, inhibitory arginine-rich motif.

Science.gov (United States)

Hurd, Matthew C; Kwon, Moonhyuk; Ro, Dae-Kyun

2017-08-26

Lippia dulcis (Aztec sweet herb) contains the potent natural sweetener hernandulcin, a sesquiterpene ketone found in the leaves and flowers. Utilizing the leaves for agricultural application is challenging due to the presence of the bitter-tasting and toxic monoterpene, camphor. To unlock the commercial potential of L. dulcis leaves, the first step of camphor biosynthesis by a bornyl diphosphate synthase needs to be elucidated. Two putative monoterpene synthases (LdTPS3 and LdTPS9) were isolated from L. dulcis leaf cDNA. To elucidate their catalytic functions, E. coli-produced recombinant enzymes with truncations of their chloroplast transit peptides were assayed with geranyl diphosphate (GPP). In vitro enzyme assays showed that LdTPS3 encodes bornyl diphosphate synthase (thus named LdBPPS) while LdTPS9 encodes linalool synthase. Interestingly, the N-terminus of LdBPPS possesses two arginine-rich (RRX 8 W) motifs, and enzyme assays showed that the presence of both RRX 8 W motifs completely inhibits the catalytic activity of LdBPPS. Only after the removal of the putative chloroplast transit peptide and the first RRX 8 W, LdBPPS could react with GPP to produce bornyl diphosphate. LdBPPS is distantly related to the known bornyl diphosphate synthase from sage in a phylogenetic analysis, indicating a converged evolution of camphor biosynthesis in sage and L. dulcis. The discovery of LdBPPS opens up the possibility of engineering L. dulcis to remove the undesirable product, camphor. Copyright © 2017 Elsevier Inc. All rights reserved.

Activation-induced cytidine deaminase induces reproducible DNA breaks at many non-Ig Loci in activated B cells

NARCIS (Netherlands)

Staszewski, Ori; Baker, Richard E.; Ucher, Anna J.; Martier, Raygene; Stavnezer, Janet; Guikema, Jeroen E. J.

2011-01-01

After immunization or infection, activation-induced cytidine deaminase (AID) initiates diversification of immunoglobulin (Ig) genes in B cells, introducing mutations within the antigen-binding V regions (somatic hypermutation, SHM) and double-strand DNA breaks (DSBs) into switch (S) regions, leading

Behavioural effects of chronic manipulations of dietary choline in senescent rats.

Science.gov (United States)

Fundaro, A; Paschero, A

1990-01-01

1. Senescent rats were maintained on choline-deficient and choline-enriched diets. The modifications in rat behaviour caused by the chronic manipulations of dietary choline were studied in two schedules of operant conditioning. 2. In the "periodic conditioning" test, the schedule of reinforcement, in a 100 min trial, was changed from a fixed ratio to a fixed interval schedule. In the "reversal" test the contingency for food delivery was switched four times from one lever to the other in a two lever Skinner box. 3. In the "periodic conditioning" test, the choline enriched group (430 mg/Kg/day) showed the same reduction of responses/reinforcement as controls, from the beginning to the end of trial; in the same group the time course reduction of responses/reinforcement became significant earlier than in the control group. The deficient-choline group in the last 40 min of "periodic conditioning" trial gave a reduction of responses/reinforcement greater than controls and one rat in the group did not learn the change of experimental schedule and extinguished its operant behaviour. 4. In the "reversal" test, the choline-enriched diet (320 mg/Kg/day) improved the reinforced responses in the IV reversal; one rat of the deficient-choline group could not learn the new operant schedule since the first reversal and continued to respond on the same lever during the whole of the test.

Cytosolic monoterpene biosynthesis is supported by plastid-generated geranyl diphosphate substrate in transgenic tomato fruits.

Science.gov (United States)

Gutensohn, Michael; Orlova, Irina; Nguyen, Thuong T H; Davidovich-Rikanati, Rachel; Ferruzzi, Mario G; Sitrit, Yaron; Lewinsohn, Efraim; Pichersky, Eran; Dudareva, Natalia

2013-08-01

Geranyl diphosphate (GPP), the precursor of most monoterpenes, is synthesized in plastids from dimethylallyl diphosphate and isopentenyl diphosphate by GPP synthases (GPPSs). In heterodimeric GPPSs, a non-catalytic small subunit (GPPS-SSU) interacts with a catalytic large subunit, such as geranylgeranyl diphosphate synthase, and determines its product specificity. Here, snapdragon (Antirrhinum majus) GPPS-SSU was over-expressed in tomato fruits under the control of the fruit ripening-specific polygalacturonase promoter to divert the metabolic flux from carotenoid formation towards GPP and monoterpene biosynthesis. Transgenic tomato fruits produced monoterpenes, including geraniol, geranial, neral, citronellol and citronellal, while exhibiting reduced carotenoid content. Co-expression of the Ocimum basilicum geraniol synthase (GES) gene with snapdragon GPPS-SSU led to a more than threefold increase in monoterpene formation in tomato fruits relative to the parental GES line, indicating that the produced GPP can be used by plastidic monoterpene synthases. Co-expression of snapdragon GPPS-SSU with the O. basilicum α-zingiberene synthase (ZIS) gene encoding a cytosolic terpene synthase that has been shown to possess both sesqui- and monoterpene synthase activities resulted in increased levels of ZIS-derived monoterpene products compared to fruits expressing ZIS alone. These results suggest that re-direction of the metabolic flux towards GPP in plastids also increases the cytosolic pool of GPP available for monoterpene synthesis in this compartment via GPP export from plastids. © 2013 The Authors The Plant Journal © 2013 John Wiley & Sons Ltd.

Two solanesyl diphosphate synthases with different subcellular localizations and their respective physiological roles in Oryza sativa.

Science.gov (United States)

Ohara, Kazuaki; Sasaki, Kanako; Yazaki, Kazufumi

2010-06-01

Long chain prenyl diphosphates are crucial biosynthetic precursors of ubiquinone (UQ) in many organisms, ranging from bacteria to humans, as well as precursors of plastoquinone in photosynthetic organisms. The cloning and characterization of two solanesyl diphosphate synthase genes, OsSPS1 and OsSPS2, in Oryza sativa is reported here. OsSPS1 was highly expressed in root tissue whereas OsSPS2 was found to be high in both leaves and roots. Enzymatic characterization using recombinant proteins showed that both OsSPS1 and OsSPS2 could produce solanesyl diphosphates as their final product, while OsSPS1 showed stronger activity than OsSPS2. However, an important biological difference was observed between the two genes: OsSPS1 complemented the yeast coq1 disruptant, which does not form UQ, whereas OsSPS2 only very weakly complemented the growth defect of the coq1 mutant. HPLC analyses showed that both OsSPS1 and OsSPS2 yeast transformants produced UQ9 instead of UQ6, which is the native yeast UQ. According to the complementation study, the UQ9 levels in OsSPS2 transformants were much lower than that of OsSPS1. Green fluorescent protein fusion analyses showed that OsSPS1 localized to mitochondria, while OsSPS2 localized to plastids. This suggests that OsSPS1 is involved in the supply of solanesyl diphosphate for ubiquinone-9 biosynthesis in mitochondria, whereas OsSPS2 is involved in providing solanesyl diphosphate for plastoquinone-9 formation. These findings indicate that O. sativa has a different mechanism for the supply of isoprenoid precursors in UQ biosynthesis from Arabidopsis thaliana, in which SPS1 provides a prenyl moiety for UQ9 at the endoplasmic reticulum.

Choline concentrations are lower in postnatal plasma of preterm infants than in cord plasma.

Science.gov (United States)

Bernhard, Wolfgang; Raith, Marco; Kunze, Rebecca; Koch, Vera; Heni, Martin; Maas, Christoph; Abele, Harald; Poets, Christian F; Franz, Axel R

2015-08-01

Choline is essential to human development, particularly of the brain in the form of phosphatidylcholine, sphingomyelin and acetylcholine, for bile and lipoprotein formation, and as a methyl group donator. Choline is actively transported into the fetus, and maternal supply correlates with cognitive outcome. Interruption of placental supply may therefore impair choline homeostasis in preterm infants. Determination of postnatal plasma concentrations of choline and its derivatives betaine and dimethylglycine (DMG) in preterm infants compared to cord and maternal blood matched for postmenstrual age (PMA). We collected plasma of very low-birth-weight infants undergoing neonatal intensive care (n = 162), cord plasma of term and preterm infants (n = 176, 24-42-week PMA), serum of parturients (n = 36), and plasma of healthy premenopausal women (n = 40). Target metabolites were analyzed with tandem mass spectrometry and reported as median (25th/75th percentiles). Cord plasma choline concentration was 41.4 (31.8-51.2) µmol/L and inversely correlated with PMA. In term but not in preterm infants, cord plasma choline was lower in girls than in boys. Prenatal glucocorticoid treatment did not affect choline levels in cord plasma, whereas betaine was decreased and DMG increased. In parturients and non-pregnant women, choline concentrations were 14.1 (10.3-16.9) and 8.8 (5.7-11.2) µmol/L, respectively, whereas betaine was lowest in parturients. After delivery, preterm infant plasma choline decreased to 20.8 (16.0-27.6) µmol/L within 48 h. Betaine and DMG correlated with plasma choline in all groups. In preterm infants, plasma choline decreases to 50 % of cord plasma concentrations, reflecting choline undernourishment and postnatal metabolic adaptation, and potentially contributing to impaired outcome.

Choline requirements of White Pekin ducks from hatch to 21 days of age.

Science.gov (United States)

Wen, Z G; Tang, J; Hou, S S; Guo, Y M; Huang, W; Xie, M

2014-12-01

A dose-response experiment with 8 dietary choline levels (302, 496, 778, 990, 1,182, 1,414, 1,625, and 1,832 mg/kg) was conducted with male White Pekin ducks to estimate the choline requirement from hatch to 21 d of age. Three hundred eighty-four 1-d-old male White Pekin ducks were randomly assigned to 8 dietary treatments, each containing 6 replicate pens with 8 birds per pen. At 21 d of age, weight gain, feed intake, and feed/gain from each pen were calculated for feeding period, and 2 ducks selected randomly from each pen were euthanized and the liver was collected to determine total lipids, triglycerides, and phospholipids. In our study, perosis, poor growth, and high liver fat were all observed in choline-deficient ducks and incidence of perosis was zero when dietary choline was 1,182 mg/kg. As dietary choline increased, the weight gain and feed intake increased linearly or quadratically (P < 0.05). On the other hand, as dietary choline increased, the total lipid and triglyceride in liver decreased linearly and liver phospholipid increased linearly (P < 0.05), and the lipotropic activity of choline may be associated with increasing phospholipid at a high dietary choline level. According to broken-line regression, the choline requirements for weight gain and feed intake were 810 and 823 mg/kg, respectively, but higher requirement should be considered to prevent perosis and excess liver lipid deposition completely. ©2014 Poultry Science Association Inc.

Spectroscopic and Computational Investigations of Ligand Binding to IspH: Discovery of Non-diphosphate Inhibitors

Energy Technology Data Exchange (ETDEWEB)

O' Dowd, Bing [Department of Chemistry, University of Illinois, 600 South Mathews Avenue Urbana IL 61801 USA; Williams, Sarah [Department of Chemistry and Biochemistry, University of California at San Diego, La Jolla CA 92093 USA; Wang, Hongxin [Department of Chemistry, University of California, 1 Shields Avenue Davis CA 95616 USA; Lawrence Berkeley National Laboratory, 1 Cyclotron Road Berkeley CA 94720 USA; No, Joo Hwan [Center for Biophysics and Computational Biology, Urbana, IL (United States); Rao, Guodong [Department of Chemistry, University of Illinois, 600 South Mathews Avenue Urbana IL 61801 USA; Wang, Weixue [Center for Biophysics and Computational Biology, Urbana, IL (United States); McCammon, J. Andrew [Department of Chemistry and Biochemistry, University of California at San Diego, La Jolla CA 92093 USA; Howard Hughes Medical Institute, University of California at San Diego, La Jolla CA 92093 USA; National Biomedical Computation Resource, University of California at San Diego, La Jolla CA 92093 USA; Cramer, Stephen P. [Department of Chemistry, University of California, 1 Shields Avenue Davis CA 95616 USA; Lawrence Berkeley National Laboratory, 1 Cyclotron Road Berkeley CA 94720 USA; Oldfield, Eric [Department of Chemistry, University of Illinois, 600 South Mathews Avenue Urbana IL 61801 USA

2017-04-07

Isoprenoid biosynthesis is an important area for anti-infective drug development. One isoprenoid target described is (E)-1-hydroxy-2-methyl-but-2-enyl 4-diphosphate (HMBPP) reductase (IspH), which forms isopentenyl diphosphate and dimethylallyl diphosphate from HMBPP in a 2H + /2e - reduction. IspH contains a 4 Fe-4 S cluster, and in this work, we first investigated how small molecules bound to the cluster by using HYSCORE and NRVS spectroscopies. The results of these, as well as other structural and spectroscopic investigations, led to the conclusion that, in most cases, ligands bound to IspH 4 Fe-4 S clusters by η 1 coordination, forming tetrahedral geometries at the unique fourth Fe, ligand side chains preventing further ligand (e.g., H 2 O, O 2 ) binding. Based on these ideas, we used in silico methods to find drug-like inhibitors that might occupy the HMBPP substrate binding pocket and bind to Fe, leading to the discovery of a barbituric acid analogue with a K i value of ≈500 nm against Pseudomonas aeruginosa IspH.

Catalytic residues Lys197 and Arg199 of Bacillus subtilis phosphoribosyl diphosphate synthase. Alanine-scanning mutagenesis of the flexible catalytic loop

DEFF Research Database (Denmark)

Hove-Jensen, Bjarne; Bentsen, Ann-Kristin K; Harlow, Kenneth W

2005-01-01

Eleven of the codons specifying the amino acids of the flexible catalytic loop [KRRPRPNVAEVM(197-208)] of Bacillus subtilis phosphoribosyl diphosphate synthase have been changed individually to specify alanine. The resulting variant enzyme forms, as well as the wildtype enzyme, were produced...... in an Escherichia coli strain lacking endogenous phosphoribosyl diphosphate synthase activity and purified to near homogeneity. The B. subtilis phosphoribosyl diphosphate synthase mutant variants K197A and R199A were studied in detail. The physical properties of the two enzymes were similar to those of the wildtype...

Evaluation of the sorption of Eu(III) in titanium diphosphate; Evaluacion de la sorcion de Eu(III) en difosfato de titanio

Energy Technology Data Exchange (ETDEWEB)

Ortiz O, H.B.; Ordonez R, E.; Fernandez V, S.M. [ININ, Carretera Mexico-Toluca Km 36.5, Salazar, Estado de Mexico (Mexico)]. e-mail: hortiz@nuclear.inin.mx

2007-07-01

In this work its are presented: the synthesis, physicochemical characterization and the surface parameters estimation that can be related with the retention properties of the titanium diphosphate for the actinides of valence III (Pu, Am, Cm among others), using the Eu{sup 3+} like a chemical analog. The surface area, hydration time, zero charge point, density of active sites and the surface species distribution in the titanium diphosphate are reported. This information was used to explain the retention of the Eu(lll) in the surface of the titanium diphosphate. (Author)

Transport and phosphorylation of choline in higher plant cells. Phosphorus-31 nuclear magnetic resonance studies

Energy Technology Data Exchange (ETDEWEB)

Bligny, R.; Foray, M.F.; Roby, C.; Douce, R.

1989-03-25

When sycamore cells were suspended in basal medium containing choline, the latter was taken up by the cells very rapidly. A facilitated diffusion system appertained at low concentrations of choline and exhibited Michaelis-Menten kinetics. At higher choline concentrations simple diffusion appeared to be the principal mode of uptake. Addition of choline to the perfusate of compressed sycamore cells monitored by /sup 31/P NMR spectroscopy resulted in a dramatic accumulation of P-choline in the cytoplasmic compartment containing choline kinase and not in the vacuole. The total accumulation of P-choline over a 10-h period exhibited Michaelis-Menten kinetics. During this period, in the absence of Pi in the perfusion medium there was a marked depletion of glucose-6-P, and the cytoplasmic Pi resonance disappeared almost completely. When a threshold of cytoplasmic Pi was attained, the phosphorylation of choline was sustained by the continuous release of Pi from the vacuole although at a much lower rate. However, when 100 microM inorganic phosphate was present in the perfusion medium, externally added Pi was preferentially used to sustain P-choline synthesis. It is clear, therefore, that cytosolic choline kinase associated with a carrier-mediated transport system for choline uptake appeared as effective systems for continuously trapping cytoplasmic Pi including vacuolar Pi entering the cytoplasm.

Influence of dietary protein and excess methionine on choline needs for young bobwhite quail

Science.gov (United States)

Serafin, J.A.

1982-01-01

Experiments were conducted with young Bobwhite quail (Colinus virginianus) to investigate the effect of differing dietary protein levels and nondetrimental amounts of excess methionine on choline needs. Growth and feed consumption of quail fed an adequate (27.3%) protein purified diet supplemented with 2000 mg/kg of choline were unaffected by increasing the level of excess methionine to 1.75%; however, greater amounts (2.0%, 2.25%) of excess methionine depressed growth (P less than .01), reduced feed consumption (P less than .01), and decreased feed utilization (P less than .05). Quail fed a purified diet containing 13.85% protein and 515 mg/kg of choline grew poorly. Growth was unaffected by additional choline in this diet. Growth was suboptimal among quail fed purified diets containing adequate or high (41.55%) levels of protein in which choline was limiting; however, a high level of protein did not in itself affect performance. Growth was improved by supplemental choline in these diets. Growth of quail fed purified diets with up to 1.35% excess methionine which were limiting (531 mg/kg) in choline was less than that of groups fed 2000 mg/kg of added dietary choline (P less than .01); however, excess methionine did not significantly influence growth of quail fed choline-deficient diets. These experiments indicate that neither high dietary protein nor excess methionine, fed at non-growth-depressing levels, increases dietary choline needs for young Bobwhite quail.

Binding of Divalent Magnesium by Escherichia coli Phosphoribosyl Diphosphate Synthetase

DEFF Research Database (Denmark)

Willemoës, Martin; Hove-Jensen, Bjarne

1997-01-01

The mechanism of binding of the substrates MgATP and ribose 5-phosphate as well as Mg2+ to the enzyme 5-phospho-d-ribosyl a-1-diphosphate synthetase from Escherichia coli has been analyzed. By use of the competive inhibitors of ATP and ribose 5-phosphate binding, a,ß-methylene ATP and (+)-1-a,2-a...

N3 and O2 Protonated Tautomeric Conformations of 2 '-Deoxycytidine and Cytidine Coexist in the Gas Phase

NARCIS (Netherlands)

Wu, R.R.; Yang, B.; Frieler, C.E.; Berden, G.; Oomens, J.; Rodgers, M.T.

2015-01-01

Infrared multiple photon dissociation action spectra of the protonated forms of the cytidyl nucleosides, 2'-deoxycytidine, [dCyd+H](+), and cytidine, [Cyd+H](+), are acquired over the IR fingerprint and hydrogen-stretching regions. Electronic structure calculations are performed at the

Reaction of uridine diphosphate galactose 4-epimerase with a suicide inactivator

International Nuclear Information System (INIS)

Flentke, G.R.; Frey, P.A.

1990-01-01

UDPgalactose 4-epimerase from Escherichia coli is rapidly inactivated by the compounds uridine 5'-diphosphate chloroacetol (UDC) and uridine 5'-diphosphate bromoacetol (UCB). Both UDC and UDB inactivate the enzyme in neutral solution concomitant with the appearance of chromophores absorbing maximally at 325 and 328 nm, respectively. The reaction of UDC with the enzyme follows saturation kinetics characterized by a K D of 0.110 mM and k inact of 0.84 min -1 at pH 8.5 and ionic strength 0.2 M. The inactivation by UDC is competitively inhibited by competitive inhibitors of UDPgalactose 4-epimerase, and it is accompanied by the tight but noncovalent binding of UDC to the enzyme in a stoichiometry of 1 mol of UDC/mol of enzyme dimer, corresponding to 1 mol of UDC/mol of enzyme-bound NAD + . The inactivation of epimerase by uridine 5'-diphosphate [ 2 H 2 ]chloroacetol proceeds with a primary kinetic isotope effect (k H /k D ) of 1.4. The inactivation mechanism is proposed to involve a minimum of three steps: (a) reversible binding of UDC to the active site of UDPgalactose 4-epimerase; (b) enolization of the chloroacetol moiety of enzyme-bound UDC, catalyzed by an enzymic general base at the active site; (c) alkylation of the nicotinamide ring of NAD + at the active site by the chloroacetol enolate. The resulting adduct between UDC and NAD + is proposed to be the chromophore with λ max at 325 nm. The enzymic general base required to facilitate proton transfer in redox catalysis by this enzyme may be the general base that facilitates enolization of the chloroacetol moiety of UDC in the inactivation reaction

The nutrigenetics and nutrigenomics of the dietary requirement for choline.

Science.gov (United States)

Corbin, Karen D; Zeisel, Steven H

2012-01-01

Advances in nutrigenetics and nutrigenomics have been instrumental in demonstrating that nutrient requirements vary among individuals. This is exemplified by studies of the nutrient choline, in which gender, single-nucleotide polymorphisms, estrogen status, and gut microbiome composition have been shown to influence its optimal intake level. Choline is an essential nutrient with a wide range of biological functions, and current studies are aimed at refining our understanding of its requirements and, importantly, on defining the molecular mechanisms that mediate its effects in instances of suboptimal dietary intake. This chapter introduces the reader to challenges in developing individual nutrition recommendations, the biological function of choline, current and future research paradigms to fully understand the consequences of inadequate choline nutrition, and some forward thinking about the potential for individualized nutrition recommendations to become a tangible application for improved health. Copyright © 2012 Elsevier Inc. All rights reserved.

Structure of dimeric, recombinant Sulfolobus solfataricus phosphoribosyl diphosphate synthase

DEFF Research Database (Denmark)

Andersen, Rune W.; Lo Leggio, Leila; Hove-Jensen, Bjarne

2015-01-01

The enzyme 5-phosphoribosyl-1-α-diphosphate (PRPP) synthase (EC 2.7.6.1) catalyses the Mg2+-dependent transfer of a diphosphoryl group from ATP to the C1 hydroxyl group of ribose 5-phosphate resulting in the production of PRPP and AMP. A nucleotide sequence specifying Sulfolobus solfataricus PRPP...

Phospholipid biosynthesis in Candida albicans: Regulation by the precursors inositol and choline

International Nuclear Information System (INIS)

Klig, L.S.; Friedli, L.; Schmid, E.

1990-01-01

Phospholipid metabolism in the pathogenic fungus Candida albicans was examined. The phospholipid biosynthetic pathways of C. albicans were elucidated and were shown to be similar to those of Saccharomyces cerevisiae. However, marked differences were seen between these two fungi in the regulation of the pathways in response to exogenously provided precursors inositol and choline. In S. cerevisiae, the biosynthesis of phosphatidylcholine via methylation of phosphatidylethanolamine appears to be regulated in response to inositol and choline; provision of choline alone does not repress the activity of this pathway. The same pathway in C. albicans responds to the exogenous provision of choline. Possible explanations for the observed differences in regulation are discussed

Choline transporter mutations in severe congenital myasthenic syndrome disrupt transporter localization.

Science.gov (United States)

Wang, Haicui; Salter, Claire G; Refai, Osama; Hardy, Holly; Barwick, Katy E S; Akpulat, Ugur; Kvarnung, Malin; Chioza, Barry A; Harlalka, Gaurav; Taylan, Fulya; Sejersen, Thomas; Wright, Jane; Zimmerman, Holly H; Karakaya, Mert; Stüve, Burkhardt; Weis, Joachim; Schara, Ulrike; Russell, Mark A; Abdul-Rahman, Omar A; Chilton, John; Blakely, Randy D; Baple, Emma L; Cirak, Sebahattin; Crosby, Andrew H

2017-11-01

The presynaptic, high-affinity choline transporter is a critical determinant of signalling by the neurotransmitter acetylcholine at both central and peripheral cholinergic synapses, including the neuromuscular junction. Here we describe an autosomal recessive presynaptic congenital myasthenic syndrome presenting with a broad clinical phenotype due to homozygous choline transporter missense mutations. The clinical phenotype ranges from the classical presentation of a congenital myasthenic syndrome in one patient (p.Pro210Leu), to severe neurodevelopmental delay with brain atrophy (p.Ser94Arg) and extend the clinical outcomes to a more severe spectrum with infantile lethality (p.Val112Glu). Cells transfected with mutant transporter construct revealed a virtually complete loss of transport activity that was paralleled by a reduction in transporter cell surface expression. Consistent with these findings, studies to determine the impact of gene mutations on the trafficking of the Caenorhabditis elegans choline transporter orthologue revealed deficits in transporter export to axons and nerve terminals. These findings contrast with our previous findings in autosomal dominant distal hereditary motor neuropathy of a dominant-negative frameshift mutation at the C-terminus of choline transporter that was associated with significantly reduced, but not completely abrogated choline transporter function. Together our findings define divergent neuropathological outcomes arising from different classes of choline transporter mutation with distinct disease processes and modes of inheritance. These findings underscore the essential role played by the choline transporter in sustaining acetylcholine neurotransmission at both central and neuromuscular synapses, with important implications for treatment and drug selection. © The Author (2017). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Expression of activation-induced cytidine deaminase is confined to B-cell non-Hodgkin's lymphomas of germinal-center phenotype

NARCIS (Netherlands)

Smit, Laura A.; Bende, Richard J.; Aten, Jan; Guikema, Jeroen E. J.; Aarts, Wilhelmina M.; van Noesel, Carel J. M.

2003-01-01

Activation-induced cytidine deaminase (AID) is essential for somatic hypermutation and class switch recombination of the immunoglobulin (IG) genes in B cells. It has recently been proposed that AID, as the newly identified DNA mutator in man, may be instrumental in initiation and progression of

Comparison of the computational NMR chemical shifts of choline with the experimental data

International Nuclear Information System (INIS)

Alcorn, C; Cuperlovic-Culf, M; Ghandi, K

2012-01-01

One of the main biological markers of the presence of cancer in living patients is an over-expression of total choline (tCho), which is the sum of free choline and its derivatives. 1 H Magnetic Resonance Spectroscopy, or H-MRS, enables the quantification of tCho via its proton spectra, and thus has the potential to be a diagnostic tool for the presence of cancer and an accurate early indicator of the response of cancer to treatment. However, it remains difficult to quantify individual choline derivatives, since they share a large structural similarity ((CH 3 ) 3 -N + -CH 2 -CH 2 -O-), of which the strongest signal detectable by MRS is that of the choline h ead group : the three methyl groups bonded to the nitrogen. This work used ACENet, a high performance computing system, to attempt to model the NMR parameters of choline derivatives, with the focus of this report being free choline. Optimized structures were determined using Density Functional Theory and the B3LYP electron correlation functional. The Polarizable Continuum Model was used to evaluate solvent effects. The Gauge-Invariant Atomic Orbital method was found to be the superior method for calculating the NMR parameters of cholines.

Selective retrograde labeling of cholinergic neurons with [3H]choline

International Nuclear Information System (INIS)

Bagnoli, P.; Beaudet, A.; Stella, M.; Cuenod, M.

1981-01-01

Evidence is presented which is consistent with a specific retrograde labeling of cholinergic neurons following [ 3 H]choline application in their zone of termination. [ 3 H]Choline injection in the rat hippocampus leads to perikaryal retrograde labeling in the ipsilateral medial septal nuclease and nucleus of the diagonal band, thus delineating an established cholinergic pathway, while only diffuse presumably anterograde labeling was observed in the lateral septum, the entorhinal cortex, and the opposite hippocampus. After [ 3 H]choline injection in the pigeon visual Wulst, only the ipsilateral thalamic relay, of all inputs, showed similar perikaryal retrograde labeling, an observation supporting the suggestion that at least some thalamo-Wulst neurons are cholinergic

In vitro optimization of non-small cell lung cancer activity with troxacitabine, L-1,3-dioxolane-cytidine, prodrugs

NARCIS (Netherlands)

Radi, Marco; Adema, Auke D.; Daft, Jonathan R.; Cho, Jong H.; Hoebe, Eveline K.; Alexander, Lou-Ella M. M.; Peters, Godefridus J.; Chu, Chung K.

2007-01-01

l-1,3-Dioxolane-cytidine, a potent anticancer agent against leukemia, has limited efficacy against solid tumors, perhaps due to its hydrophilicity. Herein, a library of prodrugs were synthesized to optimize in vitro antitumor activity against non-small cell lung cancer. N4-Substituted fatty acid

Synthesis of isoprenoid bisphosphonate ethers through C–P bond formations: Potential inhibitors of geranylgeranyl diphosphate synthase

Directory of Open Access Journals (Sweden)

Xiang Zhou

2014-07-01

Full Text Available A set of bisphosphonate ethers has been prepared through sequential phosphonylation and alkylation of monophosphonate ethers. After formation of the corresponding phosphonic acid salts, these compounds were tested for their ability to inhibit the enzyme geranylgeranyl diphosphate synthase (GGDPS. Five of the new compounds show IC50 values of less than 1 μM against GGDPS with little to no activity against the related enzyme farnesyl diphosphate synthase (FDPS. The most active compound displayed an IC50 value of 82 nM when assayed with GGDPS, and no activity against FDPS even at a 10 μM concentration.

Surface exposed amino acid differences between mesophilic and thermophilic phosphoribosyl diphosphate synthase

DEFF Research Database (Denmark)

Hove-Jensen, Bjarne; McGuire, James N

2004-01-01

The amino acid sequence of 5-phospho-alpha-D-ribosyl 1-diphosphate synthase from the thermophile Bacillus caldolyticus is 81% identical to the amino acid sequence of 5-phospho-alpha-D-ribosyl 1-diphosphate synthase from the mesophile Bacillus subtilis. Nevertheless the enzyme from the two organisms...... possesses very different thermal properties. The B. caldolyticus enzyme has optimal activity at 60-65 degrees C and a half-life of 26 min at 65 degrees C, compared to values of 46 degrees C and 60 s at 65 degrees C, respectively, for the B. subtilis enzyme. Chemical cross-linking shows that both enzymes...... are hexamers. Vmax is determined as 440 micromol.min(-1).mg protein(-1) and Km values for ATP and ribose 5-phosphate are determined as 310 and 530 microM, respectively, for the B. caldolyticus enzyme. The enzyme requires 50 mM Pi as well as free Mg2+ for maximal activity. Manganese ion substitutes for Mg2...

Are dietary choline and betaine intakes determinants of total homocysteine concentration?

Science.gov (United States)

Elevated homocysteine concentrations are associated with an increased risk of cardiovascular disease and a decline in cognitive function. Intakes of choline and betaine, as methyl donors, may affect homocysteine concentrations. The objective was to examine whether choline and betaine intakes, assess...

Transcriptional activation of a geranylgeranyl diphosphate synthase gene, GGPPS2, isolated from Scoparia dulcis by treatment with methyl jasmonate and yeast extract.

Science.gov (United States)

Yamamura, Y; Mizuguchi, Y; Taura, F; Kurosaki, F

2014-10-01

A cDNA clone, designated SdGGPPS2, was isolated from young seedlings of Scoparia dulcis. The putative amino acid sequence of the translate of the gene showed high homology with geranylgeranyl diphosphate synthase (GGPPS) from various plant sources, and the N-terminal residues exhibited the characteristics of chloroplast targeting sequence. An appreciable increase in the transcriptional level of SdGGPPS2 was observed by exposure of the leaf tissues of S. dulcis to methyl jasmonate, yeast extract or Ca(2+) ionophore A23187. In contrast, SdGGPPS1, a homologous GGPPS gene of the plant, showed no or only negligible change in the expression level upon treatment with these stimuli. The truncated protein heterologously expressed in Escherichia coli in which the putative targeting domain was deleted catalyzed the condensation of farnesyl diphosphate and isopentenyl diphosphate to liberate geranylgeranyl diphosphate. These results suggested that SdGGPPS2 plays physiological roles in methyl jasmonate and yeast extract-induced metabolism in the chloroplast of S. dulcis cells.

Organellar and cytosolic localization of four phosphoribosyl diphosphate synthase isozymes in spinach

DEFF Research Database (Denmark)

Krath, Britta N.; Hove-Jensen, Bjarne

1999-01-01

Four cDNAs encoding phosphoribosyl diphosphate (PRPP) synthase were isolated from a spinach (Spinacia oleracea) cDNA library by complementation of an Escherichia coli Δprs mutation. The four gene products produced PRPP in vitro from ATP and ribose-5-phosphate. Two of the enzymes (isozymes 1 and 2...

Pathways of acetylcholine synthesis, transport and release as targets for treatment of adult-onset cognitive dysfunction.

Science.gov (United States)

Amenta, F; Tayebati, S K

2008-01-01

Acetylcholine (ACh) is a neurotransmitter widely diffused in central, peripheral, autonomic and enteric nervous system. This paper has reviewed the main mechanisms of ACh synthesis, storage, and release. Presynaptic choline transport supports ACh production and release, and cholinergic terminals express a unique transporter critical for neurotransmitter release. Neurons cannot synthesize choline, which is ultimately derived from the diet and is delivered through the blood stream. ACh released from cholinergic synapses is hydrolyzed by acetylcholinesterase into choline and acetyl coenzyme A and almost 50% of choline derived from ACh hydrolysis is recovered by a high-affinity choline transporter. Parallel with the development of cholinergic hypothesis of geriatric memory dysfunction, cholinergic precursor loading strategy was tried for treating cognitive impairment occurring in Alzheimer's disease. Controlled clinical studies denied clinical usefulness of choline and lecithin (phosphatidylcholine), whereas for other phospholipids involved in choline biosynthetic pathways such as cytidine 5'-diphosphocholine (CDP-choline) or alpha-glyceryl-phosphorylcholine (choline alphoscerate) a modest improvement of cognitive dysfunction in adult-onset dementia disorders is documented. These inconsistencies have probably a metabolic explanation. Free choline administration increases brain choline availability but it does not increase ACh synthesis/or release. Cholinergic precursors to serve for ACh biosynthesis should be incorporate and stored into phospholipids in brain. It is probable that appropriate ACh precursors and other correlated molecules (natural or synthesized) could represent a tool for developing therapeutic strategies by revisiting and updating treatments/supplementations coming out from this therapeutic stalemate.

Dietary restriction of choline reduces hippocampal acetylcholine release in rats: in vivo microdialysis study.

Science.gov (United States)

Nakamura, A; Suzuki, Y; Umegaki, H; Ikari, H; Tajima, T; Endo, H; Iguchi, A

2001-12-01

We fed rats with a diet deficient in choline for 12 weeks and studied how dietary choline deficiency affected their behavior and their ability to release acetylcholine in discrete regions of rat brain using step-through passive avoidance task and in vivo microdialysis. In comparison with the control, rats fed the choline-deficient diet showed poorer retention of nociceptive memory in the passive avoidance task. Average choline level in cerebrospinal fluid in the choline-deficient group was significantly less (33.1%) than that of control rats. In vivo microdialysis showed no difference in the pattern of acetylcholine release enhanced by intraperitoneal administration of scopolamine hydrochloride (2 mg/kg) in the striatum between the two groups, whereas in the hippocampus, the maximum and subsequent increase of acetylcholine from the baseline by scopolamine injection was significantly lower in the choline-deficient group than in the control. From the results of our study, we speculate that long-term dietary restriction of choline can affect extra- and intracellular sources of substrates required for acetylcholine synthesis, and eventually limit the ability to release acetylcholine in the hippocampus. Reduced capacity to release acetylcholine in the hippocampus implies that the mechanism, maintaining acetylcholine synthesis on increased neuronal demand, may vary in discrete regions of the brain in response to dietary manipulation. The vulnerability of the mechanism in the hippocampus to dietary choline restriction is indicated by impaired mnemonic performance we observed.

APOBEC3G enhances lymphoma cell radioresistance by promoting cytidine deaminase-dependent DNA repair.

Science.gov (United States)

Nowarski, Roni; Wilner, Ofer I; Cheshin, Ori; Shahar, Or D; Kenig, Edan; Baraz, Leah; Britan-Rosich, Elena; Nagler, Arnon; Harris, Reuben S; Goldberg, Michal; Willner, Itamar; Kotler, Moshe

2012-07-12

APOBEC3 proteins catalyze deamination of cytidines in single-stranded DNA (ssDNA), providing innate protection against retroviral replication by inducing deleterious dC > dU hypermutation of replication intermediates. APOBEC3G expression is induced in mitogen-activated lymphocytes; however, no physiologic role related to lymphoid cell proliferation has yet to be determined. Moreover, whether APOBEC3G cytidine deaminase activity transcends to processing cellular genomic DNA is unknown. Here we show that lymphoma cells expressing high APOBEC3G levels display efficient repair of genomic DNA double-strand breaks (DSBs) induced by ionizing radiation and enhanced survival of irradiated cells. APOBEC3G transiently accumulated in the nucleus in response to ionizing radiation and was recruited to DSB repair foci. Consistent with a direct role in DSB repair, inhibition of APOBEC3G expression or deaminase activity resulted in deficient DSB repair, whereas reconstitution of APOBEC3G expression in leukemia cells enhanced DSB repair. APOBEC3G activity involved processing of DNA flanking a DSB in an integrated reporter cassette. Atomic force microscopy indicated that APOBEC3G multimers associate with ssDNA termini, triggering multimer disassembly to multiple catalytic units. These results identify APOBEC3G as a prosurvival factor in lymphoma cells, marking APOBEC3G as a potential target for sensitizing lymphoma to radiation therapy.

Cloning and Characterization of Farnesyl Diphosphate Synthase Gene Involved in Triterpenoids Biosynthesis from Poria cocos

Directory of Open Access Journals (Sweden)

Jianrong Wang

2014-12-01

Full Text Available Poria cocos (P. cocos has long been used as traditional Chinese medicine and triterpenoids are the most important pharmacologically active constituents of this fungus. Farnesyl pyrophosphate synthase (FPS is a key enzyme of triterpenoids biosynthesis. The gene encoding FPS was cloned from P. cocos by degenerate PCR, inverse PCR and cassette PCR. The open reading frame of the gene is 1086 bp in length, corresponding to a predicted polypeptide of 361 amino acid residues with a molecular weight of 41.2 kDa. Comparison of the P. cocos FPS deduced amino acid sequence with other species showed the highest identity with Ganoderma lucidum (74%. The predicted P. cocos FPS shares at least four conserved regions involved in the enzymatic activity with the FPSs of varied species. The recombinant protein was expressed in Pichia pastoris and purified. Gas chromatography analysis showed that the recombinant FPS could catalyze the formation of farnesyl diphosphate (FPP from geranyl diphosphate (GPP and isopentenyl diphosphate (IPP. Furthermore, the expression profile of the FPS gene and content of total triterpenoids under different stages of development and methyl jasmonate treatments were determined. The results indicated that there is a positive correlation between the activity of FPS and the amount of total triterpenoids produced in P. cocos.

Optimization of primaquine diphosphate tablet formulation for controlled drug release using the mixture experimental design.

Science.gov (United States)

Duque, Marcelo Dutra; Kreidel, Rogério Nepomuceno; Taqueda, Maria Elena Santos; Baby, André Rolim; Kaneko, Telma Mary; Velasco, Maria Valéria Robles; Consiglieri, Vladi Olga

2013-01-01

A tablet formulation based on hydrophilic matrix with a controlled drug release was developed, and the effect of polymer concentrations on the release of primaquine diphosphate was evaluated. To achieve this purpose, a 20-run, four-factor with multiple constraints on the proportions of the components was employed to obtain tablet compositions. Drug release was determined by an in vitro dissolution study in phosphate buffer solution at pH 6.8. The polynomial fitted functions described the behavior of the mixture on simplex coordinate systems to study the effects of each factor (polymer) on tablet characteristics. Based on the response surface methodology, a tablet composition was optimized with the purpose of obtaining a primaquine diphosphate release closer to a zero order kinetic. This formulation released 85.22% of the drug for 8 h and its kinetic was studied regarding to Korsmeyer-Peppas model, (Adj-R(2) = 0.99295) which has confirmed that both diffusion and erosion were related to the mechanism of the drug release. The data from the optimized formulation were very close to the predictions from statistical analysis, demonstrating that mixture experimental design could be used to optimize primaquine diphosphate dissolution from hidroxypropylmethyl cellulose and polyethylene glycol matrix tablets.

Choline evokes fluid secretion by perfused rat mandibular gland without desensitization

DEFF Research Database (Denmark)

Murakami, M; Novak, I; Young, J A

1986-01-01

M and evoked secretory responses comparable with those of acetylcholine (0.05-1.0 microM) administered at similar Na concentrations. Continuous infusion of choline, in contrast to acetylcholine, did not lead to a fall off in the secretory response (desensitization or tachyphylaxis) until the choline...

Role of choline PET/CT in guiding target volume delineation for irradiation of prostate cancer

Energy Technology Data Exchange (ETDEWEB)

Schwarzenboeck, S.M.; Kurth, J. [University Medical Centre Rostock, Department of Nuclear Medicine, Rostock (Germany); Gocke, C.; Kuhnt, T.; Hildebrandt, G. [University Medical Centre Rostock, Department of Radiotherapy, Rostock (Germany); Krause, B.J. [University Medical Centre Rostock, Department of Nuclear Medicine, Rostock (Germany); Universitaet Rostock, Department of Nuclear Medicine, Universitaetsmedizin Rostock, Rostock (Germany)

2013-07-15

Choline PET/CT has shown limitations for the detection of primary prostate cancer and nodal metastatic disease, mainly due to limited sensitivity and specificity. Conversely in the restaging of prostate cancer recurrence, choline PET/CT is a promising imaging modality for the detection of local regional and nodal recurrence with an impact on therapy management. This review highlights current literature on choline PET/CT for radiation treatment planning in primary and recurrent prostate cancer. Due to limited sensitivity and specificity in differentiating between benign and malignant prostatic tissues in primary prostate cancer, there is little enthusiasm for target volume delineation based on choline PET/CT. Irradiation planning for the treatment of single lymph node metastases on the basis of choline PET/CT is controversial due to its limited lesion-based sensitivity in primary nodal staging. In high-risk prostate cancer, choline PET/CT might diagnose lymph node metastases, which potentially can be included in the conventional irradiation field. Prior to radiation treatment of recurrent prostate cancer, choline PET/CT may prove useful for patient stratification by excluding distant disease which would require systemic therapy. In patients with local recurrence, choline PET/CT can be used to delineate local sites of recurrence within the prostatic resection bed allowing a boost to PET-positive sites. In patients with lymph node metastases outside the prostatic fossa and regional metastatic lymph nodes, choline PET/CT might influence radiation treatment planning by enabling extension of the target volume to lymphatic drainage sites with or without a boost to PET-positive lymph nodes. Further clinical randomized trials are required to assess treatment outcomes following choline-based biological radiation treatment planning in comparison with conventional radiation treatment planning. (orig.)

Heteromeric and homomeric geranyl diphosphate synthases from Catharanthus roseus and their role in monoterpene indole alkaloid biosynthesis.

Science.gov (United States)

Rai, Avanish; Smita, Shachi S; Singh, Anup Kumar; Shanker, Karuna; Nagegowda, Dinesh A

2013-09-01

Catharanthus roseus is the sole source of two most important monoterpene indole alkaloid (MIA) anti-cancer agents: vinblastine and vincristine. MIAs possess a terpene and an indole moiety derived from terpenoid and shikimate pathways, respectively. Geranyl diphosphate (GPP), the entry point to the formation of terpene moiety, is a product of the condensation of isopentenyl diphosphate (IPP) and dimethylallyl diphosphate (DMAPP) by GPP synthase (GPPS). Here, we report three genes encoding proteins with sequence similarity to large subunit (CrGPPS.LSU) and small subunit (CrGPPS.SSU) of heteromeric GPPSs, and a homomeric GPPSs. CrGPPS.LSU is a bifunctional enzyme producing both GPP and geranyl geranyl diphosphate (GGPP), CrGPPS.SSU is inactive, whereas CrGPPS is a homomeric enzyme forming GPP. Co-expression of both subunits in Escherichia coli resulted in heteromeric enzyme with enhanced activity producing only GPP. While CrGPPS.LSU and CrGPPS showed higher expression in older and younger leaves, respectively, CrGPPS.SSU showed an increasing trend and decreased gradually. Methyl jasmonate (MeJA) treatment of leaves significantly induced the expression of only CrGPPS.SSU. GFP localization indicated that CrGPPS.SSU is plastidial whereas CrGPPS is mitochondrial. Transient overexpression of AmGPPS.SSU in C. roseus leaves resulted in increased vindoline, immediate monomeric precursor of vinblastine and vincristine. Although C. roseus has both heteromeric and homomeric GPPS enzymes, our results implicate the involvement of only heteromeric GPPS with CrGPPS.SSU regulating the GPP flux for MIA biosynthesis.

Choline and betaine intake and colorectal cancer risk in Chinese population: a case-control study.

Directory of Open Access Journals (Sweden)

Min-Shan Lu

Full Text Available Few studies have examined the association of choline and betaine intake with colorectal cancer risk, although they might play an important role in colorectal cancer development because of their role as methyl donors. The aim of this study was to examine the relationship between consumption of choline and betaine and colorectal cancer risk in a Chinese population.A case-control study was conducted between July 2010 and December 2013 in Guangzhou, China. Eight hundred and ninety consecutively recruited colorectal cancer cases were frequency matched to 890 controls by age (5-year interval and sex. Dietary information was assessed with a validated food frequency questionnaire by face-to-face interviews. The logistic regression model was used to estimate multivariate odds ratios (ORs and 95% confidence intervals (CIs. Total choline intake was inversely associated with colorectal cancer risk after adjustment for various lifestyle and dietary factors. The multivariate-adjusted OR was 0.54 (95%CI = 0.37-0.80, Ptrend <0.01 comparing the highest with the lowest quartile. No significant associations were observed for betaine or total choline+betaine intakes. For choline-containing compounds, lower colorectal cancer risk was associated with higher intakes of choline from phosphatidylcholine, glycerophosphocholine and sphingomyelin but not for free choline and phosphocholine. The inverse association of total choline intake with colorectal cancer risk was observed in both men and women, colon and rectal cancer. These inverse associations were not modified by folate intake.These results indicate that high intake of total choline is associated with a lower risk of colorectal cancer.

ACTIVATION OF G-PROTEINS BY RECEPTOR-STIMULATED NUCLEOSIDE DIPHOSPHATE KINASE IN DICTYOSTELIUM

NARCIS (Netherlands)

Bominaar, Anthony A.; Molijn, Anco C.; Pestel, Martine; Veron, Michel; Haastert, Peter J.M. van

Recently, interest in the enzyme nucleoside diphosphate kinase (EC 2.7.4.6) has increased as a result of its possible involvement in cell proliferation and development. Since NDP kinase is one of the major sources of GTP in cells, it has been suggested that the effects of an altered NDP kinase

Radiosynthesis and pre-clinical evaluation of [{sup 18}F]fluoro-[1,2-{sup 2}H{sub 4}]choline

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Smith, Graham [Comprehensive Cancer Imaging Centre, Faculty of Medicine, Imperial College London, Hammersmith Hospital, Du Cane Road, London W12 0NN (United Kingdom); Zhao Yongjun [MDx Discovery (part of GE Healthcare) at Hammersmith Imanet, Ltd., Hammersmith Hospital, Du Cane Road, London W12 0NN (United Kingdom); Leyton, Julius [Comprehensive Cancer Imaging Centre, Faculty of Medicine, Imperial College London, Hammersmith Hospital, Du Cane Road, London W12 0NN (United Kingdom); Shan Bo [MDx Discovery (part of GE Healthcare) at Hammersmith Imanet, Ltd., Hammersmith Hospital, Du Cane Road, London W12 0NN (United Kingdom); Nguyen, Quang-de; Perumal, Meg [Comprehensive Cancer Imaging Centre, Faculty of Medicine, Imperial College London, Hammersmith Hospital, Du Cane Road, London W12 0NN (United Kingdom); Turton, David [GE-Imanet, Hammersmith Hospital, Du Cane Road, London, W12 0NN (United Kingdom); Arstad, Erik; Luthra, Sajinder K.; Robins, Edward G. [MDx Discovery (part of GE Healthcare) at Hammersmith Imanet, Ltd., Hammersmith Hospital, Du Cane Road, London W12 0NN (United Kingdom); Aboagye, Eric O., E-mail: eric.aboagye@imperial.ac.u [Comprehensive Cancer Imaging Centre, Faculty of Medicine, Imperial College London, Hammersmith Hospital, Du Cane Road, London W12 0NN (United Kingdom)

2011-01-15

Introduction: Choline radiotracers are widely used for clinical PET diagnosis in oncology. [{sup 11}C]Choline finds particular utility in the imaging of brain and prostate tumor metabolic status, where 2-[{sup 18}F]fluoro-2-deoxy-D-glucose ('FDG') shows high background uptake. More recently we have extended the clinical utility of [{sup 11}C]choline to breast cancer where radiotracer uptake correlates with tumor aggressiveness (grade). In the present study, a new choline analog, [{sup 18}F]fluoro-[1,2-{sup 2}H{sub 4}]choline, was synthesized and evaluated as a potential PET imaging probe. Methods: [{sup 18}F]Fluorocholine, [{sup 18}F]fluoro-[1-{sup 2}H{sub 2}]choline and [{sup 18}F]fluoro-[1,2-{sup 2}H{sub 4}]choline were synthesized by alkylation of the relevant precursor with [{sup 18}F]fluorobromomethane or [{sup 18}F]fluoromethyl tosylate. Radiosynthesis of [{sup 18}F]fluoromethyl tosylate required extensive modification of the existing method. [{sup 18}F]Fluorocholine and [{sup 18}F]fluoro-[1,2-{sup 2}H{sub 4}]choline were then subjected to in vitro oxidative stability analysis in a chemical oxidation model using potassium permanganate and an enzymatic model using choline oxidase. The two radiotracers, together with the corresponding di-deuterated compound, [{sup 18}F]fluoro-[1-{sup 2}H{sub 2}]choline, were then evaluated in vivo in a time-course biodistribution study in HCT-116 tumor-bearing mice. Results: Alkylation with [{sup 18}F]fluoromethyl tosylate proved to be the most reliable radiosynthetic route. Stability models indicate that [{sup 18}F]fluoro-[1,2-{sup 2}H{sub 4}]choline possesses increased chemical and enzymatic (choline oxidase) oxidative stability relative to [{sup 18}F]fluorocholine. The distribution of the three radiotracers, [{sup 18}F]fluorocholine, [{sup 18}F]fluoro-[1-{sup 2}H{sub 2}]choline and [{sup 18}F]fluoro-[1,2-{sup 2}H{sub 4}]choline, showed a similar uptake profile in most organs. Crucially, tumor uptake of [{sup 18}F

No Acute Effects of Choline Bitartrate Food Supplements on Memory in Healthy, Young, Human Adults.

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Lippelt, D P; van der Kint, S; van Herk, K; Naber, M

2016-01-01

Choline is a dietary component and precursor of acetylcholine, a crucial neurotransmitter for memory-related brain functions. In two double-blind, placebo-controlled cross-over experiments, we investigated whether the food supplement choline bitartrate improved declarative memory and working memory in healthy, young students one to two hours after supplementation. In experiment 1, 28 participants performed a visuospatial working memory task. In experiment 2, 26 participants performed a declarative picture memorization task. In experiment 3, 40 participants performed a verbal working memory task in addition to the visuospatial working memory and declarative picture task. All tasks were conducted approximately 60 minutes after the ingestion of 2.0-2.5g of either choline bitartrate or placebo. We found that choline did not significantly enhance memory performance during any of the tasks. The null hypothesis that choline does not improve memory performance as compared to placebo was strongly supported by Bayesian statistics. These results are in contrast with animal studies suggesting that choline supplementation boosts memory performance and learning. We conclude that choline likely has no acute effects on cholinergic memory functions in healthy human participants.

Prenatal choline supplementation mitigates behavioral alterations associated with prenatal alcohol exposure in rats.

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Thomas, Jennifer D; Idrus, Nirelia M; Monk, Bradley R; Dominguez, Hector D

2010-10-01

Prenatal alcohol exposure can alter physical and behavioral development, leading to a range of fetal alcohol spectrum disorders. Despite warning labels, pregnant women continue to drink alcohol, creating a need to identify effective interventions to reduce the severity of alcohol's teratogenic effects. Choline is an essential nutrient that influences brain and behavioral development. Recent studies indicate that choline supplementation can reduce the teratogenic effects of developmental alcohol exposure. The present study examined whether choline supplementation during prenatal ethanol treatment could mitigate the adverse effects of ethanol on behavioral development. Pregnant Sprague-Dawley rats were intubated with 6 g/kg/day ethanol in a binge-like manner from gestational days 5-20; pair-fed and ad libitum chow controls were included. During treatment, subjects from each group were intubated with either 250 mg/kg/day choline chloride or vehicle. Spontaneous alternation, parallel bar motor coordination, Morris water maze, and spatial working memory were assessed in male and female offspring. Subjects prenatally exposed to alcohol exhibited delayed development of spontaneous alternation behavior and deficits on the working memory version of the Morris water maze during adulthood, effects that were mitigated with prenatal choline supplementation. Neither alcohol nor choline influenced performance on the motor coordination task. These data indicate that choline supplementation during prenatal alcohol exposure may reduce the severity of fetal alcohol effects, particularly on alterations in tasks that require behavioral flexibility. These findings have important implications for children of women who drink alcohol during pregnancy. © 2010 Wiley-Liss, Inc.

Synthesis of acetylcholine from choline derived from phosphatidylcholine in a human neuronal cell line

International Nuclear Information System (INIS)

Blusztajn, J.K.; Liscovitch, M.; Richardson, U.I.

1987-01-01

Cholinergic neurons are unique among cells since they alone utilize choline not only as a component of major membrane phospholipids, such as phosphatidylcholine (Ptd-Cho), but also as a precursor of their neurotransmitter acetylcholine (AcCho). It has been hypothesized that choline-phospholipids might serve as a storage pool of choline for AcCho synthesis. The selective vulnerability of cholinergic neurons in certain neurodegenerative diseases (e.g., Alzheimer disease, motor neuron disorders) might result from the abnormally accelerated liberation of choline (to be used a precursor of AcCho) from membrane phospholipids, resulting in altered membrane composition and function and compromised neuronal viability. However, the proposed metabolic link between membrane turnover and AcCho synthesis has been difficult to demonstrate because of the heterogeneity of the preparations used. Here the authors used a population of purely cholinergic cells (human neuroblastomas, LA-N-2), incubated in the presence of [methyl- 3 H]methionine to selectively label PtdCho synthesized by methylation of phosphatidylethanolamine, the only pathway of de novo choline synthesis. Three peaks of radioactive material that cochromatographed with authentic AcCho, choline, and phosphocholine were observed when the water-soluble metabolites of the [ 3 H]PtdCho were purified by high-performance liquid chromatography. The results demonstrate that AcCho can be synthesized from choline derived from the degradation of endogenous PtdCho formed de novo by methylation of phosphatidylethanolamine

Crystal Structures of Staphylococcus epidermidis Mevalonate Diphosphate Decarboxylase Bound to Inhibitory Analogs Reveal New Insight into Substrate Binding and Catalysis

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Barta, Michael L.; Skaff, D. Andrew; McWhorter, William J.; Herdendorf, Timothy J.; Miziorko, Henry M.; Geisbrecht, Brian V. (UMKC)

2011-10-28

The polyisoprenoid compound undecaprenyl phosphate is required for biosynthesis of cell wall peptidoglycans in Gram-positive bacteria, including pathogenic Enterococcus, Streptococcus, and Staphylococcus spp. In these organisms, the mevalonate pathway is used to produce the precursor isoprenoid, isopentenyl 5-diphosphate. Mevalonate diphosphate decarboxylase (MDD) catalyzes formation of isopentenyl 5-diphosphate in an ATP-dependent irreversible reaction and is therefore an attractive target for inhibitor development that could lead to new antimicrobial agents. To facilitate exploration of this possibility, we report the crystal structure of Staphylococcus epidermidis MDD (1.85 {angstrom} resolution) and, to the best of our knowledge, the first structures of liganded MDD. These structures include MDD bound to the mevalonate 5-diphosphate analogs diphosphoglycolyl proline (2.05 {angstrom} resolution) and 6-fluoromevalonate diphosphate (FMVAPP; 2.2 {angstrom} resolution). Comparison of these structures provides a physical basis for the significant differences in K{sub i} values observed for these inhibitors. Inspection of enzyme/inhibitor structures identified the side chain of invariant Ser{sup 192} as making potential contributions to catalysis. Significantly, Ser {yields} Ala substitution of this side chain decreases k{sub cat} by {approx}10{sup 3}-fold, even though binding interactions between FMVAPP and this mutant are similar to those observed with wild type MDD, as judged by the 2.1 {angstrom} cocrystal structure of S192A with FMVAPP. Comparison of microbial MDD structures with those of mammalian counterparts reveals potential targets at the active site periphery that may be exploited to selectively target the microbial enzymes. These studies provide a structural basis for previous observations regarding the MDD mechanism and inform future work toward rational inhibitor design.

Serial plasma choline measurements after cardiac arrest in patients undergoing mild therapeutic hypothermia: a prospective observational pilot trial.

Directory of Open Access Journals (Sweden)

Christian Storm

Full Text Available OBJECTIVE: Choline is related to phospholipid metabolism and is a marker for global ischaemia with a small reference range in healthy volunteers. The aim of our study was to characterize the early kinetics of plasma free choline in patients after cardiac arrest. Additionally, we investigated the potential of plasma free choline to predict neurological outcome. METHODS: Twenty patients admitted to our medical intensive care unit were included in this prospective, observational trial. All patients were enrolled between May 2010 and May 2011. They received post cardiac arrest treatment including mild therapeutic hypothermia which was initiated with a combination of cold fluid and a feedback surface cooling device according to current guidelines. Sixteen blood samples per patient were analysed for plasma free choline levels within the first week after resuscitation. Choline was detected by liquid chromatography-tandem mass spectrometry. RESULTS: Most patients showed elevated choline levels on admission (median 14.8 µmol/L; interquartile range; IQR 9.9-20.1 which subsequently decreased. 48 hours after cardiac arrest choline levels in all patients reached subnormal levels at a median of 4.0 µmol/L (IQR 3-4.9; p = 0.001. Subsequently, choline levels normalized within seven days. There was no significant difference in choline levels when groups were analyzed in relation to neurological outcome. CONCLUSIONS: Our data indicate a choline deficiency in the early postresucitation phase. This could potentially result in impaired cell membrane recovery. The detailed characterization of the early choline time course may aid in planning of choline supplementation trials. In a limited number of patients, choline was not promising as a biomarker for outcome prediction.

Structural Basis for Nucleotide Binding and Reaction Catalysis in Mevalonate Diphosphate Decarboxylase

Energy Technology Data Exchange (ETDEWEB)

Barta, Michael L.; McWhorter, William J.; Miziorko, Henry M.; Geisbrecht, Brian V. (UMKC)

2012-09-17

Mevalonate diphosphate decarboxylase (MDD) catalyzes the final step of the mevalonate pathway, the Mg{sup 2+}-ATP dependent decarboxylation of mevalonate 5-diphosphate (MVAPP), producing isopentenyl diphosphate (IPP). Synthesis of IPP, an isoprenoid precursor molecule that is a critical intermediate in peptidoglycan and polyisoprenoid biosynthesis, is essential in Gram-positive bacteria (e.g., Staphylococcus, Streptococcus, and Enterococcus spp.), and thus the enzymes of the mevalonate pathway are ideal antimicrobial targets. MDD belongs to the GHMP superfamily of metabolite kinases that have been extensively studied for the past 50 years, yet the crystallization of GHMP kinase ternary complexes has proven to be difficult. To further our understanding of the catalytic mechanism of GHMP kinases with the purpose of developing broad spectrum antimicrobial agents that target the substrate and nucleotide binding sites, we report the crystal structures of wild-type and mutant (S192A and D283A) ternary complexes of Staphylococcus epidermidis MDD. Comparison of apo, MVAPP-bound, and ternary complex wild-type MDD provides structural information about the mode of substrate binding and the catalytic mechanism. Structural characterization of ternary complexes of catalytically deficient MDD S192A and D283A (k{sub cat} decreased 10{sup 3}- and 10{sup 5}-fold, respectively) provides insight into MDD function. The carboxylate side chain of invariant Asp{sup 283} functions as a catalytic base and is essential for the proper orientation of the MVAPP C3-hydroxyl group within the active site funnel. Several MDD amino acids within the conserved phosphate binding loop ('P-loop') provide key interactions, stabilizing the nucleotide triphosphoryl moiety. The crystal structures presented here provide a useful foundation for structure-based drug design.

A functional (E)-4-hydroxy-3-methylbut-2-enyl diphosphate reductase exhibits diurnal regulation of expression in Stevia rebaudiana (Bertoni).

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Kumar, Hitesh; Kumar, Sanjay

2013-09-15

The leaves of stevia [Stevia rebaudiana (Bertoni)] are a rich source of steviol glycosides that are used as non-calorific sweetener in many countries around the world. Steviol moiety of steviol glycosides is synthesized via plastidial 2C-methyl-D-erythritol 4-phosphate pathway, where (E)-4-hydroxy-3-methylbut-2-enyl diphosphate reductase (HDR) is the key enzyme. HDR catalyzes the simultaneous conversion of (E)-4-hydroxy-3-methylbut-2-enyl diphosphate into five carbon isoprenoid units, isopentenyl diphosphate and dimethylallyl diphosphate. Stevia HDR (SrHDR) successfully rescued HDR lethal mutant strain MG1655 araispH upon genetic complementation, suggesting SrHDR to encode a functional protein. The gene exhibited diurnal variation in expression. To identify the possible regulatory elements, upstream region of the gene was cloned and putative cis-acting elements were detected by in silico analysis. Electrophoretic mobility shift assay, using a putative light responsive element GATA showed the binding of nuclear proteins (NP) isolated from leaves during light period of the day, but not with the NP from leaves during the dark period. Data suggested the involvement of GATA box in light mediated gene regulation of SrHDR in stevia. Copyright © 2013 Elsevier B.V. All rights reserved.

Synthesis of P1-(11-phenoxyundecyl)-P2-(2-acetamido-2-deoxy-3-O-α-D-rhamnopyranosyl-α-D-glucopyranosyl) diphosphate and P1-(11-phenoxyundecyl)-P2-(2-acetamido-2-deoxy-3-O-β-D-galactopyranosyl-α-D-galactopyranosyl) diphosphate for the investigation of biosynthesis of O-antigenic polysaccharides in Pseudomonas aeruginosa and Escherichia coli O104.

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Torgov, Vladimir; Danilov, Leonid; Utkina, Natalia; Veselovsky, Vladimir; Brockhausen, Inka

2017-12-01

Two new phenoxyundecyl diphosphate sugars were synthesized for the first time: P 1 -(11-phenoxyundecyl)-P 2 - (2-acetamido-2-deoxy-3-O-α-D-rhamnopyranosyl-α-D-glucopyranosyl) diphosphate and P 1 -(11-phenoxyundecyl)-P 2 -(2-acetamido-2-deoxy-3-O-β-D-galactopyranosyl-α-D-galactopyranosyl) diphosphate to study the third step of biosynthesis of the repeating units of O-antigenic polysaccharides in Pseudomonas aeruginosa and E.coli O104 respectively. Copyright © 2017 Elsevier Ltd. All rights reserved.

Interaction between cytotoxic effects of γ-radiation and folate deficiency in relation to choline reserves

International Nuclear Information System (INIS)

Batra, Vipen; Devasagayam, Thomas Paul Asir

2009-01-01

The search for non-toxic radio-protective drugs has yielded many potential agents but most of these compounds have certain amount of toxicity. Recent studies have indicated that bio-molecules such as folate and choline might be of radio-protective value as they are, within broad dose ranges, non-toxic to humans and experimental animals. The objective of the present study was to investigate choline dependent adaptive response to potential synergistic cytotoxic effect of folate deficiency and γ-radiation. Male Swiss mice maintained on folate sufficient diet (FSD) and folate free diet (FFD) based on AIN-93 M formula, were subjected to 1-4 Gy total body γ-irradiation. To investigate liver DNA damage, apurinic/apyrimidinic sites (AP sites) were quantified. A significant increase in liver DNA AP sites with concomitant depletion of liver choline reserves was observed when γ-radiation was combined with folate deficiency. Further work in this direction suggested that cytotoxic interaction between folate deficiency and gamma radiation might induce utilization of choline and choline containing moieties by modifying levels of key regulatory enzymes dihydrofolate reductase (DHFR) and choline oxidase (ChoOx). Another major finding of these studies is that significant liver damage at higher doses of radiation (3-4 Gy), might release considerable amounts of choline reserves to serum. In conclusion, a plausible interpretation of the present studies is that folate deprivation and γ-radiation interact to mobilize additional choline reserves of hepatic tissue, for redistribution to other organs, which could not be utilized by folate deficiency alone. Present results clearly indicated a distinct choline pool in liver and kidney tissues that could be utilized by folate deficient animals only under radiation stress conditions

An electrochemiluminescence-based fibre optic biosensor for choline flow injection analysis.

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Tsafack, V C; Marquette, C A; Leca, B; Blum, L J

2000-01-01

A fibre optic biosensor based on luminol electrochemiluminescence (ECL) integrated in a flow injection analysis (FIA) system was developed for the detection of choline. The electrochemiluminescence of luminol was generated by a glassy carbon electrode polarised at +425 mV vs. a platinum pseudo-reference electrode. Choline oxidase (Chx) was immobilised either covalently on polyamide (ABC type) or on UltraBind preactivated membranes, or by physical entrapment in a photo-cross-linkable poly(vinyl alcohol) polymer (PVA-SbQ) alone or after absorption on a weak anion exchanger, DEAE (diethylaminoethyl) Sepharose. The optimisation of the reaction conditions and physicochemical parameters influencing the FIA biosensor response demonstrated that the choline biosensor exhibited the best performances in a 30 mM veronal buffer containing 30 mM KCl and 1.5 mM MgCl2, at pH 9. The use of a 0.5 ml min-1 flow rate enabled the measurement of choline by the membrane-based ECL biosensors in 8 or 5 min, with ABC or UltraBind membranes, respectively, whereas the measurement required only 3 min with the DEAE-PVA system. For comparison, the detection of choline was performed with Chx immobilised using the four different supports. The best performances were obtained with the DEAE-PVA-Chx sensing layer, which allowed a detection limit of 10 pmol, whereas with the ABC, the UltraBind and the PVA systems, the detection limits were 300 pmol, 75 pmol and 220 pmol, respectively. The DEAE-based system also exhibited a good operational stability since 160 repeated measurements of 3 nmol of choline could be performed with an RSD of 4.5% whereas the stability under the best conditions was 45 assays with the other supports.

X-ray diffraction study of choline chloride's β form

International Nuclear Information System (INIS)

Petrouleas, V.; Lemmon, R.M.; Christensen, A.

1978-01-01

The organic salt choline chloride exists in two crystalline polymorphs. One (the α form) is extraordinarily sensitive to ionizing radiation, the other (the β form) is not. The present report describes an x-ray diffraction study of the β form. The structure has been found to be highly disordered face centered cubic. A reasonable least-square refinement of the intensity data has been achieved in the centrosymmetric space group Fm3 or Fm3m by use of a molecular model with restrained bond lengths. The results show that in the β form the electronic density due to the choline cation is closely spaced around the N, so that hydrogen bonding to the chloride is unlikely. Comparison with infrared and NMR data indicates that the disordering is dynamic and can be ascribed to rotations of the choline ion around crystallographic symmetry axes. Possible connections of these results with the radiation stability of the β form are discussed

Postnatal choline supplementation selectively attenuates hippocampal microRNA alterations associated with developmental alcohol exposure.

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Balaraman, Sridevi; Idrus, Nirelia M; Miranda, Rajesh C; Thomas, Jennifer D

2017-05-01

Prenatal alcohol exposure can result in a range of physical, neuropathological, and behavioral alterations, collectively termed fetal alcohol spectrum disorders (FASD). We have shown that supplementation with the nutrient choline reduces the severity of developmental alcohol-associated deficits in hippocampal-dependent behaviors and normalizes some aspects of hippocampal cholinergic development and DNA methylation patterns. Alcohol's developmental effects may also be mediated, in part, by altering microRNAs (miRNAs) that serve as negative regulators of gene translation. To determine whether choline supplementation alters ethanol's long-lasting effects on miRNAs, Sprague-Dawley rats were exposed to 5.25 g/kg/day ethanol from postnatal days (PD) 4-9 via intubation; controls received sham intubations. Subjects were treated with choline chloride (100 mg/kg/day) or saline vehicle subcutaneously (s.c.) from PD 4-21. On PD 22, subjects were sacrificed, and RNA was isolated from the hippocampus. MiRNA expression was assessed with TaqMan Human MicroRNA Panel Low-Density Arrays. Ethanol significantly increased miRNA expression variance, an effect that was attenuated with choline supplementation. Cluster analysis of stably expressed miRNAs that exceeded an ANOVA p < 0.05 criterion indicated that for both male and female offspring, control and ethanol-exposed groups were most dissimilar from each other, with choline-supplemented groups in between. MiRNAs that expressed an average 2-fold change due to ethanol exposure were further analyzed to identify which ethanol-sensitive miRNAs were protected by choline supplementation. We found that at a false discovery rate (FDR)-adjusted criterion of p < 0.05, miR-200c was induced by ethanol exposure and that choline prevented this effect. Collectively, our data show that choline supplementation can normalize disturbances in miRNA expression following developmental alcohol exposure and can protect specific miRNAs from induction by

Dietary choline levels modify the effects of prenatal alcohol exposure in rats.

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Idrus, Nirelia M; Breit, Kristen R; Thomas, Jennifer D

Prenatal alcohol exposure can cause a range of physical and behavioral alterations; however, the outcome among children exposed to alcohol during pregnancy varies widely. Some of this variation may be due to nutritional factors. Indeed, higher rates of fetal alcohol spectrum disorders (FASD) are observed in countries where malnutrition is prevalent. Epidemiological studies have shown that many pregnant women throughout the world may not be consuming adequate levels of choline, an essential nutrient critical for brain development, and a methyl donor. In this study, we examined the influence of dietary choline deficiency on the severity of fetal alcohol effects. Pregnant Sprague-Dawley rats were randomly assigned to receive diets containing 40, 70, or 100% recommended choline levels. A group from each diet condition was exposed to ethanol (6.0g/kg/day) from gestational day 5 to 20 via intubation. Pair-fed and ad lib lab chow control groups were also included. Physical and behavioral development was measured in the offspring. Prenatal alcohol exposure delayed motor development, and 40% choline altered performance on the cliff avoidance task, independent of one another. However, the combination of low choline and prenatal alcohol produced the most severe impairments in development. Subjects exposed to ethanol and fed the 40% choline diet exhibited delayed eye openings, significantly fewer successes in hindlimb coordination, and were significantly overactive compared to all other groups. These data suggest that suboptimal intake of a single nutrient can exacerbate some of ethanol's teratogenic effects, a finding with important implications for the prevention of FASD. Copyright © 2016. Published by Elsevier Inc.

Reduction of nucleotides by ionizing radiation: uridine 5' phosphate, and cytidine 3' phosphate

International Nuclear Information System (INIS)

Box, H.C.; Potter, W.R.; Budzinski, E.E.

1974-01-01

Anions formed by the addition of an electron to the uracil base were observed in single crystals of the barium salt of uridine 5' phosphate x irradiated at 4.2 0 K. The hyperfine coupling tensor for the C 6 -H proton was deduced from ENDOR measurements; the principal values are -59.12, -32.92 and -16.24 MHz. Similar measurements were made on single crystals of cytidine 3' phosphate. The principal values for the C 6 -H proton hyperfine coupling in the anion formed on the cytosine base are -59.26, -33.98 and -14.68 MHz. (U.S.)

Structure of choline oxidase in complex with the reaction product glycine betaine.

Science.gov (United States)

Salvi, Francesca; Wang, Yuan-Fang; Weber, Irene T; Gadda, Giovanni

2014-02-01

Choline oxidase from Arthrobacter globiformis, which is involved in the biosynthesis of glycine betaine from choline, has been extensively characterized in its mechanistic and structural properties. Despite the knowledge gained on the enzyme, the details of substrate access to the active site are not fully understood. The `loop-and-lid' mechanism described for the glucose-methanol-choline enzyme superfamily has not been confirmed for choline oxidase. Instead, a hydrophobic cluster on the solvent-accessible surface of the enzyme has been proposed by molecular dynamics to control substrate access to the active site. Here, the crystal structure of the enzyme was solved in complex with glycine betaine at pH 6.0 at 1.95 Å resolution, allowing a structural description of the ligand-enzyme interactions in the active site. This structure is the first of choline oxidase in complex with a physiologically relevant ligand. The protein structures with and without ligand are virtually identical, with the exception of a loop at the dimer interface, which assumes two distinct conformations. The different conformations of loop 250-255 define different accessibilities of the proposed active-site entrance delimited by the hydrophobic cluster on the other subunit of the dimer, suggesting a role in regulating substrate access to the active site.

Value of bimodal (18)F-choline-PET/MRI and trimodal (18)F-choline-PET/MRI/TRUS for the assessment of prostate cancer recurrence after radiation therapy and radical prostatectomy.

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Paparo, Francesco; Piccardo, Arnoldo; Bacigalupo, Lorenzo; Romagnoli, Andrea; Piccazzo, Riccardo; Monticone, Michela; Cevasco, Luca; Campodonico, Fabio; Conzi, Giuseppe Maria; Carmignani, Giorgio; Rollandi, Gian Andrea

2015-08-01

Between 27% and 53% of all patients who undergo radical prostatectomy (RP) or radiation therapy (RT) as the first-line treatment of prostate cancer (PCa) develop a biochemical recurrence. Imaging plays a pivotal role in restaging by helping to distinguish between local relapse and metastatic disease (i.e., lymph-node and skeletal metastases). At present, the most promising tools for assessing PCa patients with biochemical recurrence are multiparametric magnetic resonance imaging (mpMRI) and positron emission tomography (PET)/computed tomography (CT) with radio-labeled choline derivatives. The main advantage of mpMRI is its high diagnostic accuracy in detecting local recurrence, while choline-PET/CT is able to identify lymph-node metastases when they are not suspicious on morphological imaging. The most recent advances in the field of fusion imaging have shown that multimodal co-registration, synchronized navigation, and combined interpretation are more valuable than the individual; separate assessment offered by different diagnostic techniques. The objective of the present essay was to describe the value of bimodal choline-PET/mpMRI fusion imaging and trimodal choline-PET/mpMRI/transrectal ultrasound (TRUS) in the assessment of PCa recurrence after RP and RT. Bimodal choline-PET/mpMRI fusion imaging allows morphological, functional, and metabolic information to be combined, thereby overcoming the limitations of each separate imaging modality. In addition, trimodal real-time choline-PET/mpMRI/TRUS fusion imaging may be useful for the planning and real-time guidance of biopsy procedures in order to obtain histological confirmation of the local recurrence.

Feeding a diet devoid of choline to lactating rodents restricts growth and lymphocyte development in offspring.

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Lewis, E D; Goruk, S; Richard, C; Dellschaft, N S; Curtis, J M; Jacobs, R L; Field, C J

2016-09-01

The nutrient choline is necessary for membrane synthesis and methyl donation, with increased requirements during lactation. The majority of immune development occurs postnatally, but the importance of choline supply for immune development during this critical period is unknown. The objective of this study was to determine the importance of maternal supply of choline during suckling on immune function in their offspring among rodents. At parturition, Sprague-Dawley dams were randomised to either a choline-devoid (ChD; n 7) or choline-sufficient (ChS, 1 g/kg choline; n 10) diet with their offspring euthanised at 3 weeks of age. In a second experiment, offspring were weaned to a ChS diet until 10 weeks of age (ChD-ChS, n 5 and ChS-ChS, n 9). Splenocytes were isolated, and parameters of immune function were measured. The ChD offspring received less choline in breast milk and had lower final body and organ weight compared with ChS offspring (P<0·05), but this effect disappeared by week 10 with choline supplementation from weaning. ChD offspring had a higher proportion of T cells expressing activation markers (CD71 or CD28) and a lower proportion of total B cells (CD45RA+) and responded less to T cell stimulation (lower stimulation index and less IFN-γ production) ex vivo (P<0·05). ChD-ChS offspring had a lower proportion of total and activated CD4+ T cells, and produced less IL-6 after mitogen stimulation compared with cells from ChS-ChS (P<0·05). Our study suggests that choline is required in the suckling diet to facilitate immune development, and choline deprivation during this critical period has lasting effects on T cell function later in life.

Phosphorylation of nm23/nucleoside diphosphate kinase by casein kinase 2 in vitro

DEFF Research Database (Denmark)

Engel, M; Issinger, O G; Lascu, I

1994-01-01

We have investigated phosphorylation of human nucleoside diphosphate kinase (NDPK) and of homologous NDPK from different species by human casein kinase 2 (CK-2). The human NDPK isotypes A and B were phosphorylated by CK-2 in vitro both when the purified proteins and total lysate of HL-60 leukemia...

Choline metabolism as a basis for the selective vulnerability of cholinergic neurons

Science.gov (United States)

Wurtman, R. J.

1992-01-01

The unique propensity of cholinergic neurons to use choline for two purposes--ACh and membrane phosphatidylcholine synthesis--may contribute to their selective vulnerability in Alzheimer's disease and other cholinergic neurodegenerative disorders. When physiologically active, the neurons use free choline taken from the 'reservoir' in membrane phosphatidylcholine to synthesize ACh; this can lead to an actual decrease in the quantity of membrane per cell. Alzheimer's disease (but not Down's syndrome, or other neurodegenerative disorders) is associated with characteristic neurochemical lesions involving choline and ethanolamine: brain levels of these compounds are diminished, while those of glycerophosphocholine and glycerophosphoethanolamine (breakdown products of their respective membrane phosphatides) are increased, both in cholinergic and noncholinergic brain regions. Perhaps this metabolic disturbance and the tendency of cholinergic neurons to 'export' choline--in the form of ACh--underlie the selective vulnerability of the neurons. Resulting changes in membrane composition could abnormally expose intramembraneous proteins such as amyloid precursor protein to proteases.

Uptake of [N-Me-3H]-choline by synaptosomes from the central nervous system of Locusta migratoria

International Nuclear Information System (INIS)

Breer, H.

1982-01-01

The accumulation of 3H-choline by isolated synaptosomes from the central nervous system of locust was studied at concentrations varying from 0.05 to 40 microM. Kinetic analysis of the saturable process revealed a high-affinity and a low-affinity system. The high-affinity uptake was competitively inhibited by hemicholinium-3 and was absolutely dependent on external sodium. Elevated potassium concentrations inhibited choline uptake. The choline uptake by insect synaptosomes was found to be remarkably resistant to a variety of metabolic inhibitors. The reduced choline uptake under depolarizing conditions (high potassium concentration or veratridine) in the absence of calcium implies that electrochemical gradients are important for high-affinity choline uptake. Depolarization of preloaded synaptosomes under appropriate conditions resulted in a significant release of newly accumulated choline radioactivity

Carbon Nanotubes/Gold Nanoparticles Composite Film for the Construction of a Novel Amperometric Choline Biosensor

Directory of Open Access Journals (Sweden)

Baoyan Wu

2011-01-01

Full Text Available This study develops a facile method to fabricate a novel choline biosensor based on multiwalled carbon nanotubes (MWCNTs and gold nanoparticles (AuNPs. Chitosan, a natural biocompatible polymer, was used to solubilize MWCNTs for constructing the aqueous Chit-MWCNTs solution. Then Chit-MWCNTs were first dropped on the surface of a cleaned platinum electrode. Finally, a thiolated silica sol containing AuNPs and choline oxidase (ChOx was immobilized on the surface of the Chit-MWCNTs-modified electrode. The MWCNTs/AuNPs/Pt electrode showed excellent electrocatalytic activity for choline. The resulting choline biosensor showed high sensitivity of choline (3.56 μA/mM, and wide linear range from 0.05 to 0.8 mM with the detection limit of 15 μM. In addition, good reproducibility and stability were obtained.

Dietary Intake and Plasma Levels of Choline and Betaine in Children with Autism Spectrum Disorders

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Joanna C. Hamlin

2013-01-01

Full Text Available Abnormalities in folate-dependent one-carbon metabolism have been reported in many children with autism. Because inadequate choline and betaine can negatively affect folate metabolism and in turn downstream methylation and antioxidant capacity, we sought to determine whether dietary intake of choline and betaine in children with autism was adequate to meet nutritional needs based on national recommendations. Three-day food records were analyzed for 288 children with autism (ASDs who participated in the national Autism Intervention Research Network for Physical Health (AIR-P Study on Diet and Nutrition in children with autism. Plasma concentrations of choline and betaine were measured in a subgroup of 35 children with ASDs and 32 age-matched control children. The results indicated that 60–93% of children with ASDs were consuming less than the recommended Adequate Intake (AI for choline. Strong positive correlations were found between dietary intake and plasma concentrations of choline and betaine in autistic children as well as lower plasma concentrations compared to the control group. We conclude that choline and betaine intake is inadequate in a significant subgroup of children with ASDs and is reflected in lower plasma levels. Inadequate intake of choline and betaine may contribute to the metabolic abnormalities observed in many children with autism and warrants attention in nutritional counseling.

Choline and betaine intake and colorectal cancer risk in Chinese population: a case-control study.

Science.gov (United States)

Lu, Min-Shan; Fang, Yu-Jing; Pan, Zhi-Zhong; Zhong, Xiao; Zheng, Mei-Chun; Chen, Yu-Ming; Zhang, Cai-Xia

2015-01-01

Few studies have examined the association of choline and betaine intake with colorectal cancer risk, although they might play an important role in colorectal cancer development because of their role as methyl donors. The aim of this study was to examine the relationship between consumption of choline and betaine and colorectal cancer risk in a Chinese population. A case-control study was conducted between July 2010 and December 2013 in Guangzhou, China. Eight hundred and ninety consecutively recruited colorectal cancer cases were frequency matched to 890 controls by age (5-year interval) and sex. Dietary information was assessed with a validated food frequency questionnaire by face-to-face interviews. The logistic regression model was used to estimate multivariate odds ratios (ORs) and 95% confidence intervals (CIs). Total choline intake was inversely associated with colorectal cancer risk after adjustment for various lifestyle and dietary factors. The multivariate-adjusted OR was 0.54 (95%CI = 0.37-0.80, Ptrend colorectal cancer risk was associated with higher intakes of choline from phosphatidylcholine, glycerophosphocholine and sphingomyelin but not for free choline and phosphocholine. The inverse association of total choline intake with colorectal cancer risk was observed in both men and women, colon and rectal cancer. These inverse associations were not modified by folate intake. These results indicate that high intake of total choline is associated with a lower risk of colorectal cancer.

PET/CT with 18F-choline: Physiological whole bio-distribution in male and female subjects and diagnostic pitfalls on 1000 prostate cancer patients: 18F-choline PET/CT bio-distribution and pitfalls. A southern Italian experience.

Science.gov (United States)

Calabria, Ferdinando; Chiaravalloti, Agostino; Cicciò, Carmelo; Gangemi, Vincenzo; Gullà, Domenico; Rocca, Federico; Gallo, Gianpasquale; Cascini, Giuseppe Lucio; Schillaci, Orazio

2017-08-01

The 11 C/ 18 F-choline is a PET/CT radiopharmaceutical useful in detecting tumors with high lipogenesis. 11 C/ 18 F-choline uptake can occur in physiological conditions or tumors. The knowledge of its bio-distribution is essential to recognize physiologic variants or diagnostic pitfalls. Moreover, few information are available on the bio-distribution of this tracer in female patients. Our aim was to discuss some documented 18 F-choline PET/CT pitfalls in prostate cancer patients. Our secondary aim was to describe the 18 F-choline bio-distribution in the female body. We collected diagnostic pitfalls in three PET centers examining 1000 prostate cancer by 18 F-choline PET/CT. All pitfalls were ensured by follow-up, imaging and/or histology. We also performed whole body 18 F-choline PET/CT in 5 female patients. 169/1000 (16.9%) patients showed pitfalls not owing to prostate cancer. These findings were due to inflammation, benign tumors while, in 1% of examined patients, a concomitant neoplasm was found. In the female body, the breast showed low physiological uptake. The accurate knowledge of 18 F-choline PET/CT bio-distribution and diagnostic pitfalls is essential. Correlative imaging and histological exam are often necessary to depict pitfalls. In women, the uptake in the breast is due to the physiological gradient of 18 F-choline uptake in the exocrine glands. Our results confirm the possibility of 18 F-choline uptake in several diseases other than prostate cancer. However, our experience was acquired on a large population and shows that a conspicuous amount of 18 F-choline diagnostic pitfalls are easily recognizable and attributable to inflammation. A new advance in knowledge is the minimal difference in terms of physiological tracer bio-distribution between male and female patients. The knowledge of the physiological bio-distribution and of the potential pitfalls linked of a tracer could help physicians to choose the best diagnostic and therapeutic approaches for a

Metabolic engineering of monoterpene biosynthesis in tomato fruits via introduction of the non-canonical substrate neryl diphosphate.

Science.gov (United States)

Gutensohn, Michael; Nguyen, Thuong T H; McMahon, Richard D; Kaplan, Ian; Pichersky, Eran; Dudareva, Natalia

2014-07-01

Recently it was shown that monoterpenes in tomato trichomes (Solanum lycopersicum) are synthesized by phellandrene synthase 1 (PHS1) from the non-canonical substrate neryl diphosphate (NPP), the cis-isomer of geranyl diphosphate (GPP). As PHS1 accepts both NPP and GPP substrates forming different monoterpenes, it was overexpressed in tomato fruits to test if NPP is also available in a tissue highly active in carotenoid production. However, transgenic fruits overexpressing PHS1 produced only small amounts of GPP-derived PHS1 monoterpene products, indicating the absence of endogenous NPP. Therefore, NPP formation was achieved by diverting the metabolic flux from carotenoids via expression of tomato neryl diphosphate synthase 1 (NDPS1). NDPS1 transgenic fruits produced NPP-derived monoterpenes, including nerol, neral and geranial, while displaying reduced lycopene content. NDPS1 co-expression with PHS1 resulted in a monoterpene blend, including β-phellandrene, similar to that produced from NPP by PHS1 in vitro and in trichomes. Unexpectedly, PHS1×NDPS1 fruits showed recovery of lycopene levels compared to NDPS1 fruits, suggesting that redirection of metabolic flux is only partially responsible for the reduction in carotenoids. In vitro assays demonstrated that NPP serves as an inhibitor of geranylgeranyl diphosphate synthase, thus its consumption by PHS1 leads to recovery of lycopene levels. Monoterpenes produced in PHS1×NDPS1 fruits contributed to direct plant defense negatively affecting feeding behavior of the herbivore Helicoverpa zea and displaying antifungal activity against Botrytis cinerea. These results show that NPP-derived terpenoids can be produced in plant tissues; however, NPP has to be consumed to avoid negative impacts on plant metabolism. Copyright © 2014 International Metabolic Engineering Society. Published by Elsevier Inc. All rights reserved.

Usual Choline Intakes Are Associated with Egg and Protein Food Consumption in the United States

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Taylor C. Wallace

2017-08-01

Full Text Available Choline is an essential nutrient with critical roles in several biological processes including neuronal development, cell signaling, nerve impulse transmission, and lipid transport and metabolism. The National Cancer Institute method was used to assess usual intakes of choline from foods according to data for participants enrolled in the National Health and Nutrition Examination Survey 2009–2014 datasets and pregnant women in the 2005–2014 datasets. Suboptimal intakes of choline are present across many gender and life-stage subpopulations, as well as pregnant women in the U.S. Only 8.03 ± 0.56% of adults and 8.51 ± 2.89% pregnant women meet the AI for choline. Children 2–3 years were the most likely to meet their gender and life-stage specific AI, followed by children 4–8 years. Adults 19+ years who consume eggs were more likely to meet their gender and life-stage AI as compared to non-consumers (57.3 ± 1.45% and 2.43 ± 0.28%. Consumers of eggs had almost double the usual intake of choline as compared to non-consumers (525 ± 5.17 mg/d and 294 ± 1.98; p < 0.0001. Protein food (meat, poultry and seafood consumption also increased usual choline intakes compared to non-consumers (345 ± 2.21 mg/day and 235 ± 8.81; p < 0.0001 to a lesser degree, but did not result in substantial increases in the percent of individuals meeting the AI. No subpopulation exceeded the UL for choline. This research illustrates that it is extremely difficult to achieve the AI for choline without consuming eggs or taking a dietary supplement.

Four-week dietary supplementation with 10- and/or 15-fold basal choline caused decreased body weight in Sprague Dawley rats.

Science.gov (United States)

Bagley, Bradford D; Chang, Shu-Ching; Ehresman, David J; Eveland, Alan; Parker, George A; Peters, Jeffrey M; Butenhoff, John L

2017-10-01

Choline is an essential nutrient utilized for phosphatidylcholine biosynthesis and lipoprotein packaging and secretion. Recently, choline supplementation has been used by athletes and the public for weight loss. However, the potential toxicological impact of choline dietary supplementation requires further investigation. This study examined the effects of choline dietary supplementation in Sprague Dawley rats for 4 weeks. Rats were fed diets containing basal choline levels (control) or 5-, 10-, or 15-fold (5×, 10×, or 15×) basal diet concentration. In groups fed choline-supplemented diets, there were no toxicologically relevant findings in clinical observations, food intake, clinical chemistry, liver weights, or liver histopathology. However, decreased mean body weights (8.5-10.2%) and body weight gains (24-31%) were noted for the 10× choline-supplemented (females only) and 15× choline-supplemented (both sexes) groups relative to the control groups from day 3 onward. These body weight effects were not related to a persistent reduction in average food intake. Serum cholesterol was increased in the 15× choline-supplemented male rats relative to the controls, an expected effect of choline supplementation; however, there were no changes in the serum cholesterol of female rats. Serum choline concentrations were increased in female rats relative to the male rats across all treatment groups. The maximum tolerated dose for male and female rats were the 15× and 10× choline supplements, respectively, based on decreased mean body weight and body weight gains. This study supported the conclusions of a clinical trial that showed a high choline diet can decrease body weight in humans.

Choline supplementation alleviates fluoride-induced testicular toxicity by restoring the NGF and MEK expression in mice.

Science.gov (United States)

Zhang, Jianhai; Zhang, Yufang; Liang, Chen; Wang, Nasui; Zheng, Heping; Wang, Jundong

2016-11-01

Fluoride is known to cause male reproductive toxicity, and the elucidation of its underlying mechanisms is an ongoing research focus in reproductive toxicology and epidemiology. Choline, an essential nutrient, has been extensively studied for its benefits in nervous system yet was rarely discussed for its prospective effect in male reproductive system. This study aims to explore the potential protective role of choline against NaF-induced male reproductive toxicity via MAPK pathway. The male mice were administrated by 150mg/L NaF in drinking water, 5.75g/kg choline in diet, and their combination respectively from maternal gestation to postnatal 15weeks. The results showed that fluoride exposure reduced body weight growth, lowered sperm count and survival percentages, altered testicular histology, down-regulated the mRNA expressions of NGF, Ras, Raf, and MEK genes in testes, as well as significantly decreased the expressions of both NGF and phosphor-MEK proteins in testes. Examination of data from choline-treated mice revealed that choline supplementation ameliorated these fluoride-induced changes. Taken together, our findings suggest that choline supplementation alleviates fluoride-induced testicular toxicity by restoring the NGF and phosphor-MEK expression. The suitable dosage and supplementation periods of choline await further exploration. Copyright © 2016 Elsevier Inc. All rights reserved.

Triclinic-cubic phase transition and negative expansion in the actinide IV (Th, U, Np, Pu) diphosphates

International Nuclear Information System (INIS)

Wallez, Gilles; Bregiroux, Damien; Raison, Philippe E.; Bykov, Denis; Konings, Rudy J.M.; Dacheux, Nicolas; Clavier, Nicolas; Delevoye, Laurent; Popa, Karin; Fitch, Andrew N.

2012-01-01

The AnP 2 O 7 diphosphates (An = Th, U, Np, Pu) have been synthesized by various routes depending on the stability of the An(IV) cation and its suitability for the unusual octahedral environment. Synchrotron and X-ray diffraction, thermal analysis, Raman spectroscopy, and 31 P nuclear magnetic resonance reveal them as a new family of diphosphates which probably includes the recently studied CeP 2 O 7 . Although they adopt at high temperature the same cubic archetypal cell as the other known MP 2 O 7 diphosphates, they differ by a very faint triclinic distortion at room temperature that results from an ordering of the P 2 O 7 units, as shown using high-resolution synchrotron diffraction for UP 2 O 7 . The uncommon triclinic-cubic phase transition is first order, and its temperature is very sensitive to the ionic radius of An(IV). The conflicting effects which control the thermal variations of the P-O-P angle are responsible for a strong expansion of the cell followed by a contraction at higher temperature. This inversion of expansion occurs at a temperature significantly higher than the phase transition, at variance with the parent compounds with smaller Mn(IV) cations in which the two phenomena coincide. As shown by various approaches, the P-O-b-P linkage remains bent in the cubic form. (authors)

Umbilical choline and related methylamines betaine and dimethylglycine in relation to birth weight

NARCIS (Netherlands)

Hogeveen, M.; Heijer, M. den; Semmekrot, B.A.; Sporken, J.M.J.; Ueland, P.M.; Blom, H.J.

2013-01-01

Background:Low birth weight (LBW) is associated with increased morbidity and mortality for the newborn and risk of chronic disease in adulthood. Choline plays an essential role in the integrity of cell membranes, methylation reactions, and memory development. We examined whether choline, betaine,

Galvanostatic bottom-up filling of TSV-like trenches: Choline-based leveler containing two quaternary ammoniums

International Nuclear Information System (INIS)

Kim, Myung Jun; Seo, Youngran; Kim, Hoe Chul; Lee, Yoonjae; Choe, Seunghoe; Kim, Young Gyu; Cho, Sung Ki; Kim, Jae Jeong

2015-01-01

Highlights: • The choline-based leveler having two quaternary ammoniums was synthesized. • The adsorption of this leveler with suppressor and accelerator was examined. • Galvanostatic Cu bottom-up filling was achieved with three-additive system. • The mechanism of gap-filling was elucidated based on the additive adsorption. - Abstract: Through Silicon Via (TSV) technology is essential to accomplish 3-dimensional packaging of electronics. Hence, more reliable and faster TSV filling by Cu electrodeposition is required. Our approach to improve Cu gap-filling in TSV is based on the development of new organic additives for feature filling. Here, we introduce our achievements from the synthesis of choline-based leveler to the feature filling using a synthesized leveler. The choline-based leveler, which includes two quaternary ammoniums at both ends of the molecule, is synthesized from glutaric acid. The characteristics of the choline-based additive are examined by the electrochemical analyses, and it is confirmed that the choline-based leveler shows a convection dependent adsorption behavior, which is essential for leveling. The interactions between the polymeric suppressor, accelerator, and the choline-based leveler are also investigated by changing the convection condition. Using the combination of suppressor, accelerator, and the choline-based leveler, the extreme bottom-up filling of Cu at trenches with dimensions similar to TSV are fulfilled. The mechanism of Cu gap-filling is demonstrated based on the results of electrochemical analyses and feature filling

Cerium(terbium, erbium)chloride-choline chloride aqueous systems

International Nuclear Information System (INIS)

Gajfutdinova, R.K.; Zhuravlev, E.F.; Bikbaeva, G.G.; Domrachev, V.N.; Vanskova, G.I.

1985-01-01

To clarify the effect of rare earth nature on mutual solubility of rare earth salts and amines the solubility of solid phases in the systems, consisting of choline chloride, water and cerium, terbium, erbium chlorides, has been studied. It is established, that solubility isotherms of all the systems, testify to the formation of new solid phases of the composition: Ce(Tb, Er)xCl 3 x2C 5 H 14 ONClx3H 2 O. Individuality of new solid phases is proved by DTA method, the composition is confirmed by chemical analysis and data of PMR spectra, for choline chloride and its complexes with rare earth chlorides of the given composition PMR and IR spectra are studied

Chronic choline supplementation improves cognitive and motor performance via modulating oxidative and neurochemical status in rats.

Science.gov (United States)

Tabassum, Saiqa; Haider, Saida; Ahmad, Saara; Madiha, Syeda; Parveen, Tahira

2017-08-01

Choline, an essential nutrient, accounts for multiple functions in the body and brain. While its beneficial effects on healthy adults are not clear, choline supplementation is important during pregnancy for brain development, in elderly patients for support of cognitive performance and in patients with neurological disorders to reduce memory deficits. Thus, the aim of this study is to investigate whether choline administration in healthy adult rats beneficially impacts cognitive and locomotor performance, and associated oxidative and neurochemical outcomes. Two groups, control and choline, received tap water and choline bitartrate, respectively at the dose equivalent to adequate intake for five weeks. Food intake and body weight were monitored daily. Behavioral analysis comprising assessment of cognitive performance (by novel object recognition, passive avoidance and Morris Water Maze test) and locomotor performance (by Open field, Kondziela's inverted screen and beam walking test) were performed. Following testing, rats were decapitated and brain samples were collected for estimation of acetylcholine, redox profile and monoamine measurements. The results showed that chronic choline administration significantly improves cognitive and locomotor performance accompanied by a reduction in oxidative stress, enhanced cholinergic neurotransmission and monoamine levels in the brain of healthy adult rats. Hence, chronic choline intake was found to improve behavioral, oxidative and neurochemical outcomes in the normal population, so it can be suggested that choline tablets can be used as a safe and effective supplement for improving the neurological health of normal individuals and that they might also be beneficial in preventing cognitive and motor disorders later in life. Copyright © 2017 Elsevier Inc. All rights reserved.

Choline supplementation alleviates fluoride-induced testicular toxicity by restoring the NGF and MEK expression in mice

International Nuclear Information System (INIS)

Zhang, Jianhai; Zhang, Yufang; Liang, Chen; Wang, Nasui; Zheng, Heping; Wang, Jundong

2016-01-01

Fluoride is known to cause male reproductive toxicity, and the elucidation of its underlying mechanisms is an ongoing research focus in reproductive toxicology and epidemiology. Choline, an essential nutrient, has been extensively studied for its benefits in nervous system yet was rarely discussed for its prospective effect in male reproductive system. This study aims to explore the potential protective role of choline against NaF-induced male reproductive toxicity via MAPK pathway. The male mice were administrated by 150 mg/L NaF in drinking water, 5.75 g/kg choline in diet, and their combination respectively from maternal gestation to postnatal 15 weeks. The results showed that fluoride exposure reduced body weight growth, lowered sperm count and survival percentages, altered testicular histology, down-regulated the mRNA expressions of NGF, Ras, Raf, and MEK genes in testes, as well as significantly decreased the expressions of both NGF and phosphor-MEK proteins in testes. Examination of data from choline-treated mice revealed that choline supplementation ameliorated these fluoride-induced changes. Taken together, our findings suggest that choline supplementation alleviates fluoride-induced testicular toxicity by restoring the NGF and phosphor-MEK expression. The suitable dosage and supplementation periods of choline await further exploration. - Highlights: • Fluoride exposure altered the growth and development, sperm count and sperm survival percentages, testicular histology • Fluoride exposure decreased NGF, Ras, and Mek mRNA and NGF and p-MEK protein expressions in testis of mice. • Choline supplementation diminishes fluoride-induced testicular toxicity.

Choline supplementation alleviates fluoride-induced testicular toxicity by restoring the NGF and MEK expression in mice

Energy Technology Data Exchange (ETDEWEB)

Zhang, Jianhai [Shanxi Key Laboratory of Ecological Animal Science and Environmental Veterinary Medicine, Shanxi Agricultural University, Taigu, Shanxi 030801 (China); Zhang, Yufang [Shanxi Key Laboratory of Ecological Animal Science and Environmental Veterinary Medicine, Shanxi Agricultural University, Taigu, Shanxi 030801 (China); Veterinary Station in Chen Villages of Lin Country, Linxian, Shanxi 033200 (China); Liang, Chen [Shanxi Key Laboratory of Ecological Animal Science and Environmental Veterinary Medicine, Shanxi Agricultural University, Taigu, Shanxi 030801 (China); Wang, Nasui [Division of Endocrinology and Metabolism, Department of Medicine, University of Virginia, Charlottesville, VA 22908 (United States); Division of Endocrinology and Metabolism, Department of Medicine, The First Affiliated Hospital of Shantou University Medical College, Shantou (China); Zheng, Heping [Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, VA 22908 (United States); Wang, Jundong, E-mail: wangjd53@outlook.com [Shanxi Key Laboratory of Ecological Animal Science and Environmental Veterinary Medicine, Shanxi Agricultural University, Taigu, Shanxi 030801 (China)

2016-11-01

Fluoride is known to cause male reproductive toxicity, and the elucidation of its underlying mechanisms is an ongoing research focus in reproductive toxicology and epidemiology. Choline, an essential nutrient, has been extensively studied for its benefits in nervous system yet was rarely discussed for its prospective effect in male reproductive system. This study aims to explore the potential protective role of choline against NaF-induced male reproductive toxicity via MAPK pathway. The male mice were administrated by 150 mg/L NaF in drinking water, 5.75 g/kg choline in diet, and their combination respectively from maternal gestation to postnatal 15 weeks. The results showed that fluoride exposure reduced body weight growth, lowered sperm count and survival percentages, altered testicular histology, down-regulated the mRNA expressions of NGF, Ras, Raf, and MEK genes in testes, as well as significantly decreased the expressions of both NGF and phosphor-MEK proteins in testes. Examination of data from choline-treated mice revealed that choline supplementation ameliorated these fluoride-induced changes. Taken together, our findings suggest that choline supplementation alleviates fluoride-induced testicular toxicity by restoring the NGF and phosphor-MEK expression. The suitable dosage and supplementation periods of choline await further exploration. - Highlights: • Fluoride exposure altered the growth and development, sperm count and sperm survival percentages, testicular histology • Fluoride exposure decreased NGF, Ras, and Mek mRNA and NGF and p-MEK protein expressions in testis of mice. • Choline supplementation diminishes fluoride-induced testicular toxicity.

The reduction of nucleotides by ionizing radiation: uridine 5' phosphate and cytidine 3' phosphate

International Nuclear Information System (INIS)

Box, H.C.; Potter, W.R.; Budzinski, E.E.

1975-01-01

Anions formed by the addition of an electron to the uracil base were observed in single crystals of the barium salt of uridine 5' phosphate x-irradiated at 4.2 degreeK. The hyperfine coupling tensor for the C 6 --H proton was deduced from ENDOR measurements; the principal values are -59.12, -32.92, and -16.24 MHz. Similar measurements were made on single crystals of cytidine 3' phosphate. The principal values for the C 6 --H proton hyperfine coupling in the anion formed on the cytosine base are -59.26, -33.98, and -14.68 MHz

Higher Dietary Choline and Betaine Intakes Are Associated with Better Body Composition in the Adult Population of Newfoundland, Canada.

Directory of Open Access Journals (Sweden)

Xiang Gao

Full Text Available Choline is an essential nutrient and betaine is an osmolyte and methyl donor. Both are important to maintain health including adequate lipid metabolism. Supplementation of dietary choline and betaine increase muscle mass and reduce body fat in animals. However, little data is available regarding the role of dietary choline and betaine on body composition in humans.To investigate the association between dietary choline and betaine intakes with body composition in a large population based cross-sectional study.A total of 3214 subjects from the CODING (Complex Disease in Newfoundland population: Environment and Genetics study were assessed. Dietary choline and betaine intakes were computed from the Willett Food Frequency questionnaire. Body composition was measured using dual-energy X-ray absorptiometry following a 12-hour fast. Major confounding factors including age, sex, total calorie intake and physical activity level were controlled in all analyses.Significantly inverse correlations were found between dietary choline and betaine intakes, with all obesity measurements: total percent body fat (%BF, percent trunk fat (%TF, percent android fat (%AF, percent gynoid fat (%GF and anthropometrics: weight, body mass index, waist circumference, waist-to-hip ratio in both women and men (r range from -0.13 to -0.47 for choline and -0.09 to -0.26 for betaine, p<0.001 for all. Dietary choline intake had stronger association than betaine. Moreover, obese subjects had the lowest dietary choline and betaine intakes, with overweight subjects in the middle, and normal weight subjects consumed the highest dietary choline and betaine (p<0.001. Vice versa, when subjects were ranked according to dietary choline and betaine intakes, subjects with the highest intake of both had the lowest %TF, %AF, %GF, %BF and highest %LM among the groups in both sexes.Our findings indicate that high dietary choline and betaine intakes are significantly associated with favorable body

Lecithin: a by-product of biodiesel production and a source of choline for dairy cows

Directory of Open Access Journals (Sweden)

Igino Andrighetto

2012-04-01

Full Text Available The aim of the present study was to compare the effects of soy lecithins (L, a by-product of the biodiesel production process, and choline chloride microencapsulated with hydrogenated vegetable oils (C on dry matter intake, milk yield,  milk quality traits, milk choline and haematological profile of dairy cows. A total of 12 mid-lactating Holstein Friesian cows were assigned to one of two experimental groups and fed according to cross-over design (2 diets x 2 periods. Diets were isoenergetic, isofibrous and isonitrogenous and had the same content of choline. Dry matter intake was not affected by the diet, but L led to lower milk choline (P

X-ray characteristics and thermal transformations of double diphosphates MLnP2O7 (M-K, Rb, Cs; Ln-REE of yttrium subgroup)

International Nuclear Information System (INIS)

Anisimova, N.Yu.; Chudinova, N.N.; Trunov, V.K.; AN SSSR, Moscow

1993-01-01

Results on studying double diphosphates of rare earth metals with K, Rb and Cs are studied by methods of X-ray analysis, high-temperature roentgenography and DTA. Double diphosphates of rare earth and alkali metals are crystallized in three structural types: monoclinic, rhombic and hexagonal, whereby rhombic form by heating inversely transforms into hexagonal one. MLnP 2 O 7 thermal transformations are studied

Effect of choline supplementation on rapid weight loss and biochemical variables among female taekwondo and judo athletes.

Science.gov (United States)

Elsawy, Gehan; Abdelrahman, Osama; Hamza, Amr

2014-03-27

Taekwondo and judo competitions are divided into weight categories. Many athletes reduce their body mass a few days before competition in order to obtain a competitive advantage over lighter opponents. To achieve fast body mass reduction, athletes use a number of nutritional strategies, including choline supplementation. The goal of this study was to identify the effects of choline supplementation on body mass reduction and leptin levels among female taekwondo and judo athletes. Twenty-two female athletes (15 taekwondo and 7 judo athletes) were selected from different weight categories and divided into two groups, according to weight. The players in the experimental group took choline tablets for one week before a competition. The results revealed significant differences between pre- and post-competition measurements of leptin, free plasma choline, urine choline and urine malondialdehyde levels; body mass was also reduced in the post-competition measurements. In conclusion, choline supplementation could rapidly reduce body mass without any side effects on biochemical levels or static strength.

Metabolism of choline in brain of the aged CBF-1 mouse

International Nuclear Information System (INIS)

Saito, M.; Kindel, G.; Karczmar, A.G.; Rosenberg, A.

1986-01-01

In order to quantify the changes that occur in the cholinergic central nervous system with aging, we have compared acetylcholine (Ach) formation in brain cortex slice preparations from 2-year-old aged CBF-1 mouse brains and compared the findings with those in 2-4-month-old young adult mouse brain slices. Incorporation of exogenous radioactively labelled choline (31 nM [ 3 H] choline) into acetyl choline in incubated brain slices was linear with time for 90 min. Percentage of total choline label distributed into Ach remained constant from 5 min after starting the incubation to 90 min. In contrast, distribution of label into intracellular free choline (Ch) and phosphorylcholine (Pch) changed continuously over this period suggesting that the Ch pool for Ach synthesis in brain cortex is different from that for Pch synthesis. Incorporation of radioactivity into Ach was not influenced by administration of 10 microM eserine, showing that the increment of radioactivity in Ach reflects rate of Ach formation, independently from degradation by acetylcholine esterases. Under our experimental conditions, slices from cortices of aged 24-month-old mouse brain showed a significantly greater (27%) incorporation of radioactivity into intracellular Ach than those from young, 2-4-month-old, brain cortices. Inhibitors of Ach release, 1 mM ATP or GABA, had no effect. Since concentration of radioactive precursor in the incubation medium was very low (31 nM), the Ch pool for Ach synthesis in slices was labelled without measurably changing the size of the endogenous pool. These data suggest a compensatory acceleration of Ach synthesis or else a smaller precursor pool specific for Ach synthesis into which labelled Ch migrated in aged brain

Inhibition of high affinity choline uptake by N-allyl-3-quinuclidinol

International Nuclear Information System (INIS)

Asermely, K.E.; O'Neill, J.J.

1986-01-01

The peripheral actions of N-allyl-3-quinuclidinol (N-Al-3-OHQ) on high affinity choline uptake (HAChU) on rat phrenic nerve diaphragm are described. Endplate regions (EPA) identified by the Koelle histochemical techniques for acetylcholinesterase, were dissected from adult rat hemidiaphragms and placed in cold Krebs solution (pH-7.35). All measurements of HAChU were at 37 0 C in buffers containing tritium choline (5 μM 0.124 μC/mmole) at intervals of 1, 2, 4, 8, 15 and 30 min. Tissues were washed 3x, digested in 1N NaOH and counted for tritium in Chaikoff's solution. All data are expressed as pmole Ch/g wet weight. Comparison between EPA and non-EPA tissue demonstrate HAChU and slow choline diffusion, respectively. Steady state is observed in 15 min. N-Al-3-OHQ produces 15% inhibition at 5 x 10 -5 M compared with 50% inhibition on brain synaptosomes. At 5 x 10 -4 M N-Al-3-OHQ, 30% inhibition is observed. Attempts to deplete ACh by pre-stimulation with high K + -ion (25 mM) were unsuccessful; tissue 3 H-choline uptake appeared to oscillate over a 30 min period

Inhibition of high affinity choline uptake by N-allyl-3-quinuclidinol

Energy Technology Data Exchange (ETDEWEB)

Asermely, K.E.; O' Neill, J.J.

1986-03-01

The peripheral actions of N-allyl-3-quinuclidinol (N-Al-3-OHQ) on high affinity choline uptake (HAChU) on rat phrenic nerve diaphragm are described. Endplate regions (EPA) identified by the Koelle histochemical techniques for acetylcholinesterase, were dissected from adult rat hemidiaphragms and placed in cold Krebs solution (pH-7.35). All measurements of HAChU were at 37/sup 0/C in buffers containing tritium choline (5 ..mu..M 0.124 ..mu..C/mmole) at intervals of 1, 2, 4, 8, 15 and 30 min. Tissues were washed 3x, digested in 1N NaOH and counted for tritium in Chaikoff's solution. All data are expressed as pmole Ch/g wet weight. Comparison between EPA and non-EPA tissue demonstrate HAChU and slow choline diffusion, respectively. Steady state is observed in 15 min. N-Al-3-OHQ produces 15% inhibition at 5 x 10/sup -5/ M compared with 50% inhibition on brain synaptosomes. At 5 x 10/sup -4/ M N-Al-3-OHQ, 30% inhibition is observed. Attempts to deplete ACh by pre-stimulation with high K/sup +/-ion (25 mM) were unsuccessful; tissue /sup 3/H-choline uptake appeared to oscillate over a 30 min period.

Long-term effects on biotransformation of labelled choline in different parts of the rat brain induced by single choline injections

Energy Technology Data Exchange (ETDEWEB)

Nordberg, A.; Wahlstroem, G.

1988-01-01

The long-term effects of single choline (Ch) injections on the uptake and metabolism of a tracer dose of /sup 3/H-Ch were studied in male rats. Choline was administered as a threshold infusion to obtain convulsions 10 and 4 weeks before sacrific (group 1). At a single threshold infusion of choline 4 weeks before sacrifice no convulsions were induced in 50% of the animals in a second group (group 2-) whereas convulsions were induced in the remainder of the animals in this group (group 2+). Group 3 contained control animals. One min. after administration of a tracer dose of /sup 3/H-Ch the animals were sacrificed and examined for /sup 3/H-total activity, /sup 3/H-Ch, /sup 3/H-acetylcholine (/sup 3/H-ACh) and /sup 3/H-phosphorylcholine (/sup 3/-H-PhCh). These activities were determined in three parts of the brain (cortex, striatum, midbrain + medulla oblongata). In the cortex a significant negative correlation between brain weight and /sup 3/H-ACh synthesis was seen in group 1. A comparison between group 2+ and group 2- indicated that induced convulsions were not critical for this effect. In the striatum there was a significant reduction in the total uptake of radioactivity in group 1 and group 2- when values were compared to the control group. Furthermore a significant positive correlation was detected between the concentration of radiolabel and /sup 3/H-ACh synthesis and a negative relationship with the level of /sup 3/H-Ch. In the midbrain preparation the synthesis of /sup 3/H-ACh was reduced in group 1 where a significant negative correlation was found between the average threshold dose of choline and both /sup 3/H-Ach and /sup 3/H-PhCh synthesis. Thus the Ch threshold doses given several weeks before testing seem to have long term effects on the uptake and utilization of a tracer dose of /sup 3/H-Ch in the cortex and striatum.

Suppressing Farnesyl Diphosphate Synthase Alters Chloroplast Development and Triggers Sterol-Dependent Induction of Jasmonate- and Fe-Related Responses.

Science.gov (United States)

Manzano, David; Andrade, Paola; Caudepón, Daniel; Altabella, Teresa; Arró, Montserrat; Ferrer, Albert

2016-09-01

Farnesyl diphosphate synthase (FPS) catalyzes the synthesis of farnesyl diphosphate from isopentenyl diphosphate and dimethylallyl diphosphate. Arabidopsis (Arabidopsis thaliana) contains two genes (FPS1 and FPS2) encoding FPS. Single fps1 and fps2 knockout mutants are phenotypically indistinguishable from wild-type plants, while fps1/fps2 double mutants are embryo lethal. To assess the effect of FPS down-regulation at postembryonic developmental stages, we generated Arabidopsis conditional knockdown mutants expressing artificial microRNAs devised to simultaneously silence both FPS genes. Induction of silencing from germination rapidly caused chlorosis and a strong developmental phenotype that led to seedling lethality. However, silencing of FPS after seed germination resulted in a slight developmental delay only, although leaves and cotyledons continued to show chlorosis and altered chloroplasts. Metabolomic analyses also revealed drastic changes in the profile of sterols, ubiquinones, and plastidial isoprenoids. RNA sequencing and reverse transcription-quantitative polymerase chain reaction transcriptomic analysis showed that a reduction in FPS activity levels triggers the misregulation of genes involved in biotic and abiotic stress responses, the most prominent one being the rapid induction of a set of genes related to the jasmonic acid pathway. Down-regulation of FPS also triggered an iron-deficiency transcriptional response that is consistent with the iron-deficient phenotype observed in FPS-silenced plants. The specific inhibition of the sterol biosynthesis pathway by chemical and genetic blockage mimicked these transcriptional responses, indicating that sterol depletion is the primary cause of the observed alterations. Our results highlight the importance of sterol homeostasis for normal chloroplast development and function and reveal important clues about how isoprenoid and sterol metabolism is integrated within plant physiology and development. © 2016

A putative antiviral role of plant cytidine deaminases [version 2; referees: 2 approved

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Susana Martín

2017-06-01

Full Text Available Background: A mechanism of innate antiviral immunity operating against viruses infecting mammalian cells has been described during the last decade.  Host cytidine deaminases (e.g., APOBEC3 proteins edit viral genomes, giving rise to hypermutated nonfunctional viruses; consequently, viral fitness is reduced through lethal mutagenesis.  By contrast, sub-lethal hypermutagenesis may contribute to virus evolvability by increasing population diversity.  To prevent genome editing, some viruses have evolved proteins that mediate APOBEC3 degradation.  The model plant Arabidopsis thaliana genome encodes nine cytidine deaminases (AtCDAs, raising the question of whether deamination is an antiviral mechanism in plants as well. Methods: Here we tested the effects of expression of AtCDAs on the pararetrovirus Cauliflower mosaic virus (CaMV. Two different experiments were carried out. First, we transiently overexpressed each one of the nine A. thaliana AtCDA genes in Nicotiana bigelovii plants infected with CaMV, and characterized the resulting mutational spectra, comparing them with those generated under normal conditions.  Secondly, we created A. thaliana transgenic plants expressing an artificial microRNA designed to knock-out the expression of up to six AtCDA genes.  This and control plants were then infected with CaMV.  Virus accumulation and mutational spectra where characterized in both types of plants. Results:  We have shown that the A. thaliana AtCDA1 gene product exerts a mutagenic activity, significantly increasing the number of G to A mutations in vivo, with a concomitant reduction in the amount of CaMV genomes accumulated.  Furthermore, the magnitude of this mutagenic effect on CaMV accumulation is positively correlated with the level of AtCDA1 mRNA expression in the plant. Conclusions: Our results suggest that deamination of viral genomes may also work as an antiviral mechanism in plants.

Involvement of activation-induced cytidine deaminase in skin cancer development.

Science.gov (United States)

Nonaka, Taichiro; Toda, Yoshinobu; Hiai, Hiroshi; Uemura, Munehiro; Nakamura, Motonobu; Yamamoto, Norio; Asato, Ryo; Hattori, Yukari; Bessho, Kazuhisa; Minato, Nagahiro; Kinoshita, Kazuo

2016-04-01

Most skin cancers develop as the result of UV light-induced DNA damage; however, a substantial number of cases appear to occur independently of UV damage. A causal link between UV-independent skin cancers and chronic inflammation has been suspected, although the precise mechanism underlying this association is unclear. Here, we have proposed that activation-induced cytidine deaminase (AID, encoded by AICDA) links chronic inflammation and skin cancer. We demonstrated that Tg mice expressing AID in the skin spontaneously developed skin squamous cell carcinoma with Hras and Trp53 mutations. Furthermore, genetic deletion of Aicda reduced tumor incidence in a murine model of chemical-induced skin carcinogenesis. AID was expressed in human primary keratinocytes in an inflammatory stimulus-dependent manner and was detectable in human skin cancers. Together, the results of this study indicate that inflammation-induced AID expression promotes skin cancer development independently of UV damage and suggest AID as a potential target for skin cancer therapeutics.

Prenatal choline deficiency does not enhance hippocampal vulnerability after kainic acid-induced seizures in adulthood.

Science.gov (United States)

Wong-Goodrich, Sarah J E; Tognoni, Christina M; Mellott, Tiffany J; Glenn, Melissa J; Blusztajn, Jan K; Williams, Christina L

2011-09-21

Choline is a vital nutrient needed during early development for both humans and rodents. Severe dietary choline deficiency during pregnancy leads to birth defects, while more limited deficiency during mid- to late pregnancy causes deficits in hippocampal plasticity in adult rodent offspring that are accompanied by cognitive deficits only when task demands are high. Because prenatal choline supplementation confers neuroprotection of the adult hippocampus against a variety of neural insults and aids memory, we hypothesized that prenatal choline deficiency may enhance vulnerability to neural injury. To examine this, adult offspring of rat dams either fed a control diet (CON) or one deficient in choline (DEF) during embryonic days 12-17 were given multiple injections (i.p.) of saline (control) or kainic acid to induce seizures and were euthanized 16 days later. Perhaps somewhat surprisingly, DEF rats were not more susceptible to seizure induction and showed similar levels of seizure-induced hippocampal histopathology, GAD expression loss, upregulated hippocampal GFAP and growth factor expression, and increased dentate cell and neuronal proliferation as that seen in CON rats. Although prenatal choline deficiency compromises adult hippocampal plasticity in the intact brain, it does not appear to exacerbate the neuropathological response to seizures in the adult hippocampus at least shortly after excitotoxic injury. Copyright © 2011 Elsevier B.V. All rights reserved.

A mechanism for suppression of the CDP-choline pathway during apoptosis

OpenAIRE

Morton, Craig C.; Aitchison, Adam J.; Gehrig, Karsten; Ridgway, Neale D.

2013-01-01

Inhibition of the CDP-choline pathway during apoptosis restricts the availability of phosphatidylcholine (PtdCho) for assembly of membranes and synthesis of signaling factors. The N-terminal nuclear localization signal (NLS) in CTP:phosphocholine cytidylyltransferase (CCT)α is removed during apoptosis but the caspase(s) involved and the contribution to suppression of the CDP-choline pathway is unresolved. In this study we utilized siRNA silencing of caspases in HEK293 cells and caspase 3-defi...

Usefulness of Choline-PET for the detection of residual hemangiopericytoma in the skull base: comparison with FDG-PET

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Ito Shin

2012-02-01

Full Text Available Abstract Background Choline is a new PET tracer that is useful for the detection of malignant tumor. Choline is a precursor of the biosynthesis of phosphatidylcholine, a major phospholipid in the cell membrane of eukaryotic cells. Malignant tumors have an elevated level of phosphatidylcholine in cell membrane. Thus, choline is a marker of tumor malignancy. Method The patient was a 51-year-old man with repeated recurrent hemangiopericytoma in the skull base. We performed Choline-PET in this patient after various treatments and compared findings with those of FDG-PET. Results Choline accumulated in this tumor, but FDG did not accumulate. We diagnosed this tumor as residual hemangiopericytoma and performed the resection of the residual tumor. FDG-PET is not appropriate for skull base tumor detection because uptake in the brain is very strong. Conclusion We emphasize the usefulness of Choline-PET for the detection of residual hemangiopericytoma in the skull base after various treatments, compared with FDG-PET.

Effect of dimethylaminoethanol, an inhibitor of betaine production, on the disposition of choline in the rat kidney

International Nuclear Information System (INIS)

Lohr, J.; Acara, M.

1990-01-01

The choline metabolite betaine has been shown to be an important organic osmoregulatory solute in the kidney. The isolated perfused rat kidney and kidney slice incubations were used to investigate the effect of 2-dimethylaminoethanol (DMAE), a choline oxidase inhibitor, on the renal excretion and metabolism of choline. In the isolated perfused kidney, [ 14 C]choline, at an initial perfusate concentration of 300 microM, was effectively removed from the perfusate over 25 min, with nearly all the 14 C in the perfusate accounted for by betaine during the remainder of the 90-min perfusion. DMAE at concentrations of 3.0 or 5.0 mM significantly decreased the rate of removal of [ 14 C]choline from the perfusate and the rate of addition of [ 14 C]betaine to the perfusate, yet [14C]betaine remained the only metabolite of choline in perfusate and urine. In kidney tissue slice experiments, conversion of [ 14 C]choline to [ 14 C]betaine was found in cortical, outer medullary and inner medullary regions of rat kidney. DMAE at 5.0 mM significantly inhibited [ 14 C]betaine production in each of the three regions studied. These data show that DMAE is an effective inhibitor of betaine production by the kidney and, as such, may be an important agent for the study of osmoregulation by the kidney

Characterization and detection of a widely distributed gene cluster that predicts anaerobic choline utilization by human gut bacteria.

Science.gov (United States)

Martínez-del Campo, Ana; Bodea, Smaranda; Hamer, Hilary A; Marks, Jonathan A; Haiser, Henry J; Turnbaugh, Peter J; Balskus, Emily P

2015-04-14

Elucidation of the molecular mechanisms underlying the human gut microbiota's effects on health and disease has been complicated by difficulties in linking metabolic functions associated with the gut community as a whole to individual microorganisms and activities. Anaerobic microbial choline metabolism, a disease-associated metabolic pathway, exemplifies this challenge, as the specific human gut microorganisms responsible for this transformation have not yet been clearly identified. In this study, we established the link between a bacterial gene cluster, the choline utilization (cut) cluster, and anaerobic choline metabolism in human gut isolates by combining transcriptional, biochemical, bioinformatic, and cultivation-based approaches. Quantitative reverse transcription-PCR analysis and in vitro biochemical characterization of two cut gene products linked the entire cluster to growth on choline and supported a model for this pathway. Analyses of sequenced bacterial genomes revealed that the cut cluster is present in many human gut bacteria, is predictive of choline utilization in sequenced isolates, and is widely but discontinuously distributed across multiple bacterial phyla. Given that bacterial phylogeny is a poor marker for choline utilization, we were prompted to develop a degenerate PCR-based method for detecting the key functional gene choline TMA-lyase (cutC) in genomic and metagenomic DNA. Using this tool, we found that new choline-metabolizing gut isolates universally possessed cutC. We also demonstrated that this gene is widespread in stool metagenomic data sets. Overall, this work represents a crucial step toward understanding anaerobic choline metabolism in the human gut microbiota and underscores the importance of examining this microbial community from a function-oriented perspective. Anaerobic choline utilization is a bacterial metabolic activity that occurs in the human gut and is linked to multiple diseases. While bacterial genes responsible for

Re-editing the paradigm of Cytidine (C) to Uridine (U) RNA editing.

Science.gov (United States)

Fossat, Nicolas; Tam, Patrick P L

2014-01-01

Cytidine (C) to Uridine (U) RNA editing is a post-trancriptional modification that until recently was known to only affect Apolipoprotein b (Apob) RNA and minimally require 2 components of the C to U editosome, the deaminase APOBEC1 and the RNA-binding protein A1CF. Our latest work has identified a novel RNA-binding protein, RBM47, as a core component of the editosome, which can substitute A1CF for the editing of ApoB mRNA. In addition, new RNA species that are subjected to C to U editing have been identified. Here, we highlight these recent discoveries and discuss how they change our view of the composition of the C to U editing machinery and expand our knowledge of the functional attributes of C to U RNA editing.

Asymmetric Modification of Hepatitis B Virus (HBV) Genomes by an Endogenous Cytidine Deaminase inside HBV Cores Informs a Model of Reverse Transcription.

Science.gov (United States)

Nair, Smita; Zlotnick, Adam

2018-05-15

Cytidine deaminases inhibit replication of a broad range of DNA viruses by deaminating cytidines on single-stranded DNA (ssDNA) to generate uracil. While several lines of evidence have revealed hepatitis B virus (HBV) genome editing by deamination, it is still unclear which nucleic acid intermediate of HBV is modified. Hepatitis B virus has a relaxed circular double-stranded DNA (rcDNA) genome that is reverse transcribed within virus cores from a RNA template. The HBV genome also persists as covalently closed circular DNA (cccDNA) in the nucleus of an infected cell. In the present study, we found that in HBV-producing HepAD38 and HepG2.2.15 cell lines, endogenous cytidine deaminases edited 10 to 25% of HBV rcDNA genomes, asymmetrically with almost all mutations on the 5' half of the minus strand. This region corresponds to the last half of the minus strand to be protected by plus-strand synthesis. Within this half of the genome, the number of mutations peaks in the middle. Overexpressed APOBEC3A and APOBEC3G could be packaged in HBV capsids but did not change the amount or distribution of mutations. We found no deamination on pregenomic RNA (pgRNA), indicating that an intact genome is encapsidated and deaminated during or after reverse transcription. The deamination pattern suggests a model of rcDNA synthesis in which pgRNA and then newly synthesized minus-sense single-stranded DNA are protected from deaminase by interaction with the virus capsid; during plus-strand synthesis, when enough dsDNA has been synthesized to displace the remaining minus strand from the capsid surface, the single-stranded DNA becomes deaminase sensitive. IMPORTANCE Host-induced mutation of the HBV genome by APOBEC proteins may be a path to clearing the virus. We examined cytidine-to-thymidine mutations in the genomes of HBV particles grown in the presence or absence of overexpressed APOBEC proteins. We found that genomes were subjected to deamination activity during reverse transcription

Class II recombinant phosphoribosyl diphosphate synthase from spinach

DEFF Research Database (Denmark)

Krath, B N; Hove-Jensen, B

2001-01-01

to other PRPP synthases the activity of spinach PRPP synthase isozyme 3 is independent of P(i), and the enzyme is inhibited by ribonucleoside diphosphates in a purely competitive manner, which indicates a lack of allosteric inhibition by these compounds. In addition spinach PRPP synthase isozyme 3 shows...... an unusual low specificity toward diphosphoryl donors by accepting dATP, GTP, CTP, and UTP in addition to ATP. The kinetic mechanism of the enzyme is an ordered steady state Bi Bi mechanism with K(ATP) and K(Rib-5-P) values of 170 and 110 micrometer, respectively, and a V(max) value of 13.1 micromol (min x...... mg of protein)(-1). The enzyme has an absolute requirement for magnesium ions, and maximal activity is obtained at 40 degrees C at pH 7.6....

Effect of choline chloride supplementation on milk production and milk composition of Etawah grade goats

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Supriyati

2016-08-01

Full Text Available Abstract Background The effect of choline chloride supplementation through forced drinking combined with concentrate diets containing Ca-fish oil on milk production and milk composition of Etawah Grade goats was evaluated. Choline chloride is an essential component in ruminant diets as it is required for fat metabolism. Method The experiment was conducted in a completely randomized block design with three types of treatments and eight replications. The trial had two successive experimental periods; the first, during the eight weeks of late pregnancy, and the second, during the first 12 weeks of lactation. Twenty-four Etawah Grade does in the second gestation period were divided into three treatment groups. Commercial choline chloride 60 % in corncobs-based powder was used as a source of choline chloride. The treatments were no supplementation (control and supplemented with either 4 g or 8 g/2days of choline chloride. Choline chloride was given to the animals through a forced drinking technique, after dissolving it in 60 ml drinking water. The initial body weight of does was 38.81 ± 3.66 kg. The does were penned individually, and were given fresh chopped King Grass ad libitum and 700 g/day of concentrate diets containing Ca-fish oil, starting eight weeks prior to expecting kidding and continuing for 12 weeks of parturition. Results All nutrient intakes were not significantly different (p > 0.05 among the treatments during the late pregnancy and the lactation periods. Supplementation did not affect (p > 0.05 the average daily gains and feed conversion ratio during pregnancy but gave effects (p < 0.05 on the average daily gains, feed conversion ratio and income over feed cost during lactation. The highest average daily milk yields and 4 % fat corrected milk yields were found in goats supplemented with 4 g/2days of choline chloride and increased by 17.00 % and 24.67 %, respectively, compared to the control. Moreover, milk

Structural studies on choline-carboxylate bio-ionic liquids by x-ray scattering and molecular dynamics.

Science.gov (United States)

Tanzi, Luana; Ramondo, Fabio; Caminiti, Ruggero; Campetella, Marco; Di Luca, Andrea; Gontrani, Lorenzo

2015-09-21

We report a X-ray diffraction and molecular dynamics study on three choline-based bio-ionic liquids, choline formate, [Ch] [For], choline propanoate, [Ch][Pro], and choline butanoate, [Ch][But]. For the first time, this class of ionic liquids has been investigated by X-ray diffraction. Experimental and theoretical structure factors have been compared for each term of the series. Local structural organization has been obtained from ab initio calculations through static models of isolated ion pairs and dynamic simulations of small portions of liquids through twelve, ten, and nine ion pairs for [Ch][For], [Ch][Pro], and [Ch][But], respectively. All the theoretical models indicate that cations and anions are connected by strong hydrogen bonding and form stable ion pairs in the liquid that are reminiscent of the static ab initio ion pairs. Different structural aspects may affect the radial distribution function, like the local structure of ion pairs and the conformation of choline. When small portions of liquids have been simulated by dynamic quantum chemical methods, some key structural features of the X-ray radial distribution function were well reproduced whereas the classical force fields here applied did not entirely reproduce all the observed structural features.

Structural studies on choline-carboxylate bio-ionic liquids by x-ray scattering and molecular dynamics

International Nuclear Information System (INIS)

Tanzi, Luana; Ramondo, Fabio; Caminiti, Ruggero; Campetella, Marco; Di Luca, Andrea; Gontrani, Lorenzo

2015-01-01

We report a X-ray diffraction and molecular dynamics study on three choline-based bio-ionic liquids, choline formate, [Ch] [For], choline propanoate, [Ch][Pro], and choline butanoate, [Ch][But]. For the first time, this class of ionic liquids has been investigated by X-ray diffraction. Experimental and theoretical structure factors have been compared for each term of the series. Local structural organization has been obtained from ab initio calculations through static models of isolated ion pairs and dynamic simulations of small portions of liquids through twelve, ten, and nine ion pairs for [Ch][For], [Ch][Pro], and [Ch][But], respectively. All the theoretical models indicate that cations and anions are connected by strong hydrogen bonding and form stable ion pairs in the liquid that are reminiscent of the static ab initio ion pairs. Different structural aspects may affect the radial distribution function, like the local structure of ion pairs and the conformation of choline. When small portions of liquids have been simulated by dynamic quantum chemical methods, some key structural features of the X-ray radial distribution function were well reproduced whereas the classical force fields here applied did not entirely reproduce all the observed structural features

Structural studies on choline-carboxylate bio-ionic liquids by x-ray scattering and molecular dynamics

Energy Technology Data Exchange (ETDEWEB)

Tanzi, Luana; Ramondo, Fabio, E-mail: fabio.ramondo@univaq.it [Department of Physical and Chemical Sciences, University of L’Aquila, Via Vetoio, L’Aquila I-67100 (Italy); Caminiti, Ruggero; Campetella, Marco; Di Luca, Andrea; Gontrani, Lorenzo, E-mail: lorenzo.gontrani@uniroma1.it [Department of Chemistry, University of Rome ‘La Sapienza’, P.le Aldo Moro 5, I-00185 Rome (Italy)

2015-09-21

We report a X-ray diffraction and molecular dynamics study on three choline-based bio-ionic liquids, choline formate, [Ch] [For], choline propanoate, [Ch][Pro], and choline butanoate, [Ch][But]. For the first time, this class of ionic liquids has been investigated by X-ray diffraction. Experimental and theoretical structure factors have been compared for each term of the series. Local structural organization has been obtained from ab initio calculations through static models of isolated ion pairs and dynamic simulations of small portions of liquids through twelve, ten, and nine ion pairs for [Ch][For], [Ch][Pro], and [Ch][But], respectively. All the theoretical models indicate that cations and anions are connected by strong hydrogen bonding and form stable ion pairs in the liquid that are reminiscent of the static ab initio ion pairs. Different structural aspects may affect the radial distribution function, like the local structure of ion pairs and the conformation of choline. When small portions of liquids have been simulated by dynamic quantum chemical methods, some key structural features of the X-ray radial distribution function were well reproduced whereas the classical force fields here applied did not entirely reproduce all the observed structural features.

[11C]Choline PET/CT predicts survival in hormone-naive prostate cancer patients with biochemical failure after radical prostatectomy

International Nuclear Information System (INIS)

Giovacchini, Giampiero; Incerti, Elena; Mapelli, Paola; Gianolli, Luigi; Picchio, Maria; Kirienko, Margarita; Briganti, Alberto; Gandaglia, Giorgio; Montorsi, Francesco

2015-01-01

Over the last decade, PET/CT with radiolabelled choline has been shown to be useful for restaging patients with prostate cancer (PCa) who develop biochemical failure. The limitations of most clinical studies have been poor validation of [ 11 C]choline PET/CT-positive findings and lack of survival analysis. The aim of this study was to assess whether [ 11 C]choline PET/CT can predict survival in hormone-naive PCa patients with biochemical failure. This retrospective study included 302 hormone-naive PCa patients treated with radical prostatectomy who underwent [ 11 C]choline PET/CT from 1 December 2004 to 31 July 2007 because of biochemical failure (prostate-specific antigen, PSA, >0.2 ng/mL). Median PSA was 1.02 ng/mL. PCa-specific survival was estimated using Kaplan-Meier curves. Cox regression analysis was used to evaluate the association between clinicopathological variables and PCa-specific survival. The coefficients of the covariates included in the Cox regression analysis were used to develop a novel nomogram. Median follow-up was 7.2 years (1.4 - 18.9 years). [ 11 C]Choline PET/CT was positive in 101 of 302 patients (33 %). Median PCa-specific survival after prostatectomy was 14.9 years (95 % CI 9.7 - 20.1 years) in patients with positive [ 11 C]choline PET/CT. Median survival was not achieved in patients with negative [ 11 C]choline PET/CT. The 15-year PCa-specific survival probability was 42.4 % (95 % CI 31.7 - 53.1 %) in patients with positive [ 11 C]choline PET/CT and 95.5 % (95 % CI 93.5 - 97.5 %) in patients with negative [ 11 C]choline PET/CT. In multivariate analysis, [ 11 C]choline PET/CT (hazard ratio 6.36, 95 % CI 2.14 - 18.94, P < 0.001) and Gleason score >7 (hazard ratio 3.11, 95 % CI 1.11 - 8.66, P = 0.030) predicted PCa-specific survival. An internally validated nomogram predicted 15-year PCa-specific survival probability with an accuracy of 80 %. Positive [ 11 C]choline PET/CT after biochemical failure predicts PCa-specific survival in hormone

Gold nanoparticle–choline complexes can block nicotinic acetylcholine receptors

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Chur Chin

2010-04-01

Full Text Available Chur Chin1, In Kyeom Kim2, Dong Yoon Lim3, Ki Suk Kim4, Hyang Ae Lee4, Eun Joo Kim41Department of Pediatrics, Fatima Hospital, Daegu, Korea; 2Department of Pharmacology, School of Medicine, Kyungpook National University, Daegu, Korea; 3Department of Pharmacology, School of Medicine, Chosun University, Gwangju, Korea; 4Korea Institute of Toxicology, Daejeon, KoreaAbstract: We identified a novel class of direct ion-channel blockers of ligand-gated ion channels called the gold nanoparticle–choline complex. Negatively charged gold nanoparticles (1.4 nm block ion pores by binding to the sulfur group of the cysteine loop of nicotinic acetylcholine receptors (nAChRs, and currents evoked by acetylcholine (Ach can break these bonds. The current evoked by ACh in nAChRs was blocked directly in ion pores by the gold nanoparticle–choline complex. In adrenal-gland perfusion studies, the complex also blocked nAChRs by diminishing catecholamine release by about 75%. An in vivo study showed muscle relaxation in rats after injection of the complex. These results will foster the application of gold nanoparticles as a direct ion-channel blocker. Keywords: negatively charged gold nanoparticle, choline, gold–sulfur bond, nicotinic acetylcholine receptor, direct ion-channel blocker

Review on Carbon Dioxide Absorption by Choline Chloride/Urea Deep Eutectic Solvents

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Rima J. Isaifan

2018-01-01

Full Text Available In the recent past few years, deep eutectic solvents (DESs were developed sharing similar characteristics to ionic liquids but with more advantageous features related to preparation cost, environmental impact, and efficiency for gas separation processes. Amongst many combinations of DES solvents that have been prepared, reline (choline chloride as the hydrogen bond acceptor mixed with urea as the hydrogen bond donor was the first DES synthesized and is still the one with the lowest melting point. Choline chloride/urea DES has proven to be a promising solvent as an efficient medium for carbon dioxide capture when compared with amine alone or ionic liquids under the same conditions. This review sheds light on the preparation method, physical and chemical characteristics, and the CO2 absorption capacity of choline chloride/urea DES under different temperatures and pressures reported up to date.

Suppressing Farnesyl Diphosphate Synthase Alters Chloroplast Development and Triggers Sterol-Dependent Induction of Jasmonate- and Fe-Related Responses1[OPEN

Science.gov (United States)

Andrade, Paola; Caudepón, Daniel; Arró, Montserrat

2016-01-01

Farnesyl diphosphate synthase (FPS) catalyzes the synthesis of farnesyl diphosphate from isopentenyl diphosphate and dimethylallyl diphosphate. Arabidopsis (Arabidopsis thaliana) contains two genes (FPS1 and FPS2) encoding FPS. Single fps1 and fps2 knockout mutants are phenotypically indistinguishable from wild-type plants, while fps1/fps2 double mutants are embryo lethal. To assess the effect of FPS down-regulation at postembryonic developmental stages, we generated Arabidopsis conditional knockdown mutants expressing artificial microRNAs devised to simultaneously silence both FPS genes. Induction of silencing from germination rapidly caused chlorosis and a strong developmental phenotype that led to seedling lethality. However, silencing of FPS after seed germination resulted in a slight developmental delay only, although leaves and cotyledons continued to show chlorosis and altered chloroplasts. Metabolomic analyses also revealed drastic changes in the profile of sterols, ubiquinones, and plastidial isoprenoids. RNA sequencing and reverse transcription-quantitative polymerase chain reaction transcriptomic analysis showed that a reduction in FPS activity levels triggers the misregulation of genes involved in biotic and abiotic stress responses, the most prominent one being the rapid induction of a set of genes related to the jasmonic acid pathway. Down-regulation of FPS also triggered an iron-deficiency transcriptional response that is consistent with the iron-deficient phenotype observed in FPS-silenced plants. The specific inhibition of the sterol biosynthesis pathway by chemical and genetic blockage mimicked these transcriptional responses, indicating that sterol depletion is the primary cause of the observed alterations. Our results highlight the importance of sterol homeostasis for normal chloroplast development and function and reveal important clues about how isoprenoid and sterol metabolism is integrated within plant physiology and development. PMID

11C-choline vs. 18F-FDG PET/CT in assessing bone involvement in patients with multiple myeloma

Directory of Open Access Journals (Sweden)

Ambrosini Valentina

2007-06-01

Full Text Available Abstract Background Multiple Myeloma (MM is a B cell neoplasm causing lytic or osteopenic bone abnormalities. Whole body skeletal survey (WBSS, Magnetic resonance (MR and 18F-FDG PET/CT are imaging techniques routinely used for the evaluation of bone involvement in MM patients. Aim As MM bone lesions may present low 18F-FDG uptake; the aim of this study was to assess the possible added value and limitations of 11C-Choline to that of 18F-FDG PET/CT in patients affected with MM. Methods Ten patients affected with MM underwent a standard 11C-Choline PET/CT and an 18F-FDG PET/CT within one week. The results of the two scans were compared in terms of number, sites and SUVmax of lesions. Results Four patients (40% had a negative concordant 11C-Choline and 18F-FDG PET/CT scans. Two patients (20% had a positive 11C-Choline and 18F-FDG PET/CT scans that identified the same number and sites of bone lesions. The remaining four patients (40% had a positive 11C-Choline and 18F-FDG PET/CT scan, but the two exams identified different number of lesions. Choline showed a mean SUVmax of 5 while FDG showed a mean SUVmax of 3.8 (P = 0.042. Overall, 11C-Choline PET/CT scans detected 37 bone lesions and 18F-FDG PET/CT scans detected 22 bone lesions but the difference was not significant (P = 0.8. Conclusion According to these preliminary data, 11C-Choline PET/CT appears to be more sensitive than 18F-FDG PET/CT for the detection of bony myelomatous lesions. If these data are confirmed in larger series of patients, 11C-Choline may be considered a more appropriate functional imaging in association with MRI for MM bone staging.

No Acute Effects of Choline Bitartrate Food Supplements on Memory in Healthy, Young, Human Adults

NARCIS (Netherlands)

Lippelt, Dominique; van der Kint, Sander; van Herk, Kevin; Naber, M.

2016-01-01

Choline is a dietary component and precursor of acetylcholine, a crucial neurotransmitter for memory-related brain functions. In two double-blind, placebo-controlled cross-over experiments, we investigated whether the food supplement choline bitartrate improved declarative memory and working memory

Structure of the ent-Copalyl Diphosphate Synthase PtmT2 from Streptomyces platensis CB00739, a Bacterial Type II Diterpene Synthase.

Science.gov (United States)

Rudolf, Jeffrey D; Dong, Liao-Bin; Cao, Hongnan; Hatzos-Skintges, Catherine; Osipiuk, Jerzy; Endres, Michael; Chang, Chin-Yuan; Ma, Ming; Babnigg, Gyorgy; Joachimiak, Andrzej; Phillips, George N; Shen, Ben

2016-08-31

Terpenoids are the largest and most structurally diverse family of natural products found in nature, yet their presence in bacteria is underappreciated. The carbon skeletons of terpenoids are generated through carbocation-dependent cyclization cascades catalyzed by terpene synthases (TSs). Type I and type II TSs initiate cyclization via diphosphate ionization and protonation, respectively, and protein structures of both types are known. Most plant diterpene synthases (DTSs) possess three α-helical domains (αβγ), which are thought to have arisen from the fusion of discrete, ancestral bacterial type I TSs (α) and type II TSs (βγ). Type II DTSs of bacterial origin, of which there are no structurally characterized members, are a missing piece in the structural evolution of TSs. Here, we report the first crystal structure of a type II DTS from bacteria. PtmT2 from Streptomyces platensis CB00739 was verified as an ent-copalyl diphosphate synthase involved in the biosynthesis of platensimycin and platencin. The crystal structure of PtmT2 was solved at a resolution of 1.80 Å, and docking studies suggest the catalytically active conformation of geranylgeranyl diphosphate (GGPP). Site-directed mutagenesis confirmed residues involved in binding the diphosphate moiety of GGPP and identified DxxxxE as a potential Mg(2+)-binding motif for type II DTSs of bacterial origin. Finally, both the shape and physicochemical properties of the active sites are responsible for determining specific catalytic outcomes of TSs. The structure of PtmT2 fundamentally advances the knowledge of bacterial TSs, their mechanisms, and their role in the evolution of TSs.

Uptake of 3H-choline and synthesis of 3H-acetylcholine by human penile corpus cavernosum

International Nuclear Information System (INIS)

Blanco, R.; Saenz de Tejada, I.; Azadzoi, K.; Goldstein, I.; Krane, R.J.; Wotiz, H.H.; Cohen, R.A.

1986-01-01

The neuroeffectors which relax penile smooth muscle and lead to erection are unknown; physiological studies of human corpus cavernosum, in vitro, have suggested a significant role of cholinergic neurotransmission. To further characterize the importance of cholinergic nerves, biopsies of human corpus cavernosum were obtained at the time of penile prosthesis implantation. Tissues were incubated in 3 H-choline (10 -5 M, 80 Ci/mmol) in oxygenated physiological salt solution at 37 0 C, pH 7.4 for 1 hour. Radiolabelled compounds were extracted with perchloric acid (0.4 M) and acetylcholine and choline were separated by HPLC; 14 C-acetylcholine was used as internal standard. 3 H-choline was accumulated by the tissues (20 +/- 1.9 fmol/mg), and 3 H-acetylcholine was synthesized (4.0 +/- 1.1 fmol/mg). In control experiments, heating of the tissue blocked synthesis of 3 H-acetylcholine. Inhibition of high affinity choline transport by hemicholinium-3 (10 -5 M) diminished tissue accumulation of 3 H-choline and significantly reduced the synthesis of 3 H-acetylcholine (0.5 +/ 0.2 fmol/mg, p < 0.05). These results provide direct evidence of neuronal accumulation of choline and enzymatic conversion to acetylcholine in human corpus cavernosum. Taken together with the physiological studies, it can be concluded that cholinergic neurotransmission in human corpus cavernosum plays a role in penile erection

Crystal structure of heterodimeric hexaprenyl diphosphate synthase from Micrococcus luteus B-P 26 reveals that the small subunit is directly involved in the product chain length regulation.

Science.gov (United States)

Sasaki, Daisuke; Fujihashi, Masahiro; Okuyama, Naomi; Kobayashi, Yukiko; Noike, Motoyoshi; Koyama, Tanetoshi; Miki, Kunio

2011-02-04

Hexaprenyl diphosphate synthase from Micrococcus luteus B-P 26 (Ml-HexPPs) is a heterooligomeric type trans-prenyltransferase catalyzing consecutive head-to-tail condensations of three molecules of isopentenyl diphosphates (C(5)) on a farnesyl diphosphate (FPP; C(15)) to form an (all-E) hexaprenyl diphosphate (HexPP; C(30)). Ml-HexPPs is known to function as a heterodimer of two different subunits, small and large subunits called HexA and HexB, respectively. Compared with homooligomeric trans-prenyltransferases, the molecular mechanism of heterooligomeric trans-prenyltransferases is not yet clearly understood, particularly with respect to the role of the small subunits lacking the catalytic motifs conserved in most known trans-prenyltransferases. We have determined the crystal structure of Ml-HexPPs both in the substrate-free form and in complex with 7,11-dimethyl-2,6,10-dodecatrien-1-yl diphosphate ammonium salt (3-DesMe-FPP), an analog of FPP. The structure of HexB is composed of mostly antiparallel α-helices joined by connecting loops. Two aspartate-rich motifs (designated the first and second aspartate-rich motifs) and the other characteristic motifs in HexB are located around the diphosphate part of 3-DesMe-FPP. Despite the very low amino acid sequence identity and the distinct polypeptide chain lengths between HexA and HexB, the structure of HexA is quite similar to that of HexB. The aliphatic tail of 3-DesMe-FPP is accommodated in a large hydrophobic cleft starting from HexB and penetrating to the inside of HexA. These structural features suggest that HexB catalyzes the condensation reactions and that HexA is directly involved in the product chain length control in cooperation with HexB.

Perfluorooctane Sulfonate-Induced Hepatic Steatosis in Male Sprague Dawley Rats Is Not Attenuated by Dietary Choline Supplementation.

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Bagley, Bradford D; Chang, Shu-Ching; Ehresman, David J; Eveland, Alan; Zitzow, Jeremiah D; Parker, George A; Peters, Jeffrey M; Wallace, Kendall B; Butenhoff, John L

2017-12-01

Perfluorooctane sulfonate (PFOS) is an environmentally persistent chemical. Dietary 100 ppm PFOS fed to male mice and rats for 4 weeks caused hepatic steatosis through an unknown mechanism. Choline deficient diets can cause hepatic steatosis. A hepatic choline:PFOS ion complex was hypothesized to cause this effect in mice. This study tested whether dietary choline supplementation attenuates PFOS-induced hepatic steatosis in rats. Sprague Dawley rats (12/sex/group) were fed control, choline supplemented (CS), 100 ppm PFOS, or 100 ppm PFOS + CS diets for 3 weeks. Male rats fed both PFOS-containing diets had decreased serum cholesterol and triglycerides (TGs) on days 9, 16, and/or 23 and increased hepatic free fatty acids and TG (ie, steatosis). Female rats fed both PFOS diets had decreased serum cholesterol on days 9 and 16 and decreased hepatic free fatty acid and TG at termination (ie, no steatosis). Liver PFOS concentrations were similar for both sexes. Liver choline concentrations were increased in male rats fed PFOS (±CS), but the increase was lower in the PFOS + CS group. Female liver choline concentrations were not altered by any diet. These findings demonstrate a clear sex-related difference in PFOS-induced hepatic steatosis in the rat. Additional evaluated mechanisms (ie, nuclear receptor activation, mRNA upregulation, and choline kinase activity inhibition) did not appear to be involved in the hepatic steatosis. Dietary PFOS (100 ppm) induced hepatic steatosis in male, but not female, rats that was not attenuated by choline supplementation. The mechanism of lipid accumulation and the sex-related differences warrant further investigation. © The Author 2017. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Verbal and visual memory improve after choline supplementation in long-term total parenteral nutrition: a pilot study.

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Buchman, A L; Sohel, M; Brown, M; Jenden, D J; Ahn, C; Roch, M; Brawley, T L

2001-01-01

Previous investigations have demonstrated that choline deficiency, manifested in low plasma-free choline concentration and hepatic injury, may develop in patients who require long-term total parenteral nutrition (TPN). Preliminary studies have suggested lecithin or choline supplementation might lead to improved visual memory in the elderly and reverse abnormal neuropsychological development in children. We sought to determine if choline-supplemented TPN would lead to improvement in neuropsychological test scores in a group of adult, choline-deficient outpatients receiving TPN. Eleven subjects (8 males, 3 females) who received nightly TPN for more than 80% of their nutritional needs for at least 12 weeks before entry in the study were enrolled. Exclusion criteria included active drug abuse, mental retardation, cerebral vascular accident, head trauma, hemodialysis or peritoneal dialysis, (prothrombin time [PT] >2x control), or acquired immune deficiency syndrome (AIDS). Patients were randomly assigned to receive their usual TPN regimen (n = 6, aged 34.0 +/- 12.6 years) over a 12-hour nightly infusion or their usual TPN regimen plus choline chloride (2 g) (n = 5, aged 37.3 +/- 7.3 years). The following neuropsychological tests were administered at baseline and after 24 weeks of choline supplementation (or placebo): Weschler Adult Intelligence Scale-Revised (WAIS-R, intellectual functioning), Weschler Memory Scale-Revised (WMS-R, two subtests, verbal and visual memory), Rey-Osterrieth Complex Figure Test (visuospatial functioning and perceptual organization), Controlled Oral Word Association Test (verbal fluency), Grooved Pegboard (manual dexterity and motor speed), California Verbal Learning Test (CVLT, rote verbal learning ability), and Trail Making Parts A & B (visual scanning, psychomotor speed and set shifting). Scores were reported in terms of standard scores including z scores and percentile ranks. Mean absolute changes in raw scores were compared between groups

Synthesis and preclinical evaluation of the choline transport tracer deshydroxy-[18F]fluorocholine ([18F]dOC)

International Nuclear Information System (INIS)

Henriksen, G.; Herz, M.; Hauser, A.; Schwaiger, M.; Wester, H.-J.

2004-01-01

11 C-labeled choline ([ 11 C]CHO) and 18 F-fluorinated choline analogues have been demonstrated to be valuable tracers for in vivo imaging of neoplasms by means of positron emission tomography (PET). The objective of the present study was to evaluate whether deshydroxy-[ 18 F]fluorocholine, ([ 18 F]dOC), a non-metabolizable [ 18 F]fluorinated choline analogue, can serve as a surrogate for cholines that are able to be phosphorylated and thus allow PET-imaging solely by addressing the choline transport system. The specificity of uptake of [ 18 F]dOC was compared with that of [ 11 C]choline ([ 11 C]CHO) in cultured rat pancreatic carcinoma and PC-3 human prostate cancer cells in vitro. In addition, biodistribution of [ 18 F]dOC and [ 11 C]CHO was compared in AR42J- and PC-3 tumor bearing mice. The in vitro studies revealed that membrane transport of both compounds can be inhibited in a concentration dependent manner by similar concentrations of cold choline (IC 50 [ 18 F]dOC= 11 μM; IC 50 [ 11 C]CHO=13 μM. In vitro studies with PC-3 and AR42J cells revealed that the internalized fraction of [ 18 F]dOC after 5 min incubation time is comparable to that of [ 11 C]CHO, whereas the uptake of [ 11 C]CHO was superior after 20 min incubation time. As for [ 11 C]CHO, kidney and liver were also the primary sites of uptake for [ 18 F]dOC in vivo. Biodistribution data after simultaneous injection of both tracers into AR42J tumor bearing mice revealed slightly higher tumor uptake for [ 18 F]dOC at 10 min post-injection, whereas [ 11 C]CHO uptake was higher at later time points. In conclusion, [ 18 F]dOC is taken up into AR42J rat pancreatic carcinoma and PC-3 human prostate cancer cells by a choline specific transport system. Similar transport rates of [ 18 F]dOC and [ 11 C]CHO result in comparable cellular uptake levels at early time points. In contrast to [ 18 F]dOC, which is transported but not intracellularily trapped, the choline kinase substrate [ 11 C]CHO is transported

Optimization of catalyst-solvent system for preparation of alpha-5,6-dihydro-5-aza-2'-deoxy-[6-3H]-cytidine

Czech Academy of Sciences Publication Activity Database

Elbert, Tomáš

2011-01-01

Roč. 54, č. 5 (2011), s. 285-285 ISSN 0362-4803. [Workshop of the International Isotope Society - Central European Division. The Synthesis and Applications of Isotopes and Isotopically Labelled Compounds /17./. 23.09.2010-24.09.2010, Bad Soden] Institutional research plan: CEZ:AV0Z40550506 Keywords : tritium * labelled compounds * alfa-5,6-dihydro-5-aza-2'-deoxy-cytidine Subject RIV: CC - Organic Chemistry

Myeloprotection by Cytidine Deaminase Gene Transfer in Antileukemic Therapy

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Nico Lachmann

2013-03-01

Full Text Available Gene transfer of drug resistance (CTX-R genes can be used to protect the hematopoietic system from the toxicity of anticancer chemotherapy and this concept recently has been proven by overexpression of a mutant O6-methylguaninemethyltransferase in the hematopoietic system of glioblastoma patients treated with temozolomide. Given its protection capacity against such relevant drugs as cytosine arabinoside (ara-C, gemcitabine, decitabine, or azacytidine and the highly hematopoiesis-specific toxicity profile of several of these agents, cytidine deaminase (CDD represents another interesting candidate CTX-R gene and our group recently has established the myeloprotective capacity of CDD gene transfer in a number of murine transplant studies. Clinically, CDD overexpression appears particularly suited to optimize treatment strategies for acute leukemias and myelodysplasias given the efficacy of ara-C (and to a lesser degree decitabine and azacytidine in these disease entities. This article will review the current state of the art with regard to CDD gene transfer and point out potential scenarios for a clinical application of this strategy. In addition, risks and potential side effects associated with this approach as well as strategies to overcome these problems will be highlighted.

Role of carbon-11 choline PET/CT in the management of uterine carcinoma. Initial experience

International Nuclear Information System (INIS)

Sofue, Keitaro; Sawada, Morio; Arai, Yasuaki; Tateishi, Ukihide; Inoue, Tomio; Maeda, Tetsuo; Sugimura, Kazuro; Terauchi, Takashi; Kano, Daisuke

2009-01-01

The present study was conducted to clarify the role of carbon-11 choline ( 11 C-choline) positron emission tomography (PET)/computed tomography (CT) in the management of uterine carcinoma. Twenty-two patients who underwent 11 C-choline PET/CT and pelvic MRI were evaluated retrospectively. The images were reviewed by a board-certified radiologist and a nuclear medicine specialist who were unaware of any clinical information, and a consensus was reached. Diagnostic accuracy of PET/CT was evaluated for staging. The reference standard consisted of histological examination (n=17) and follow-up conventional CT (n=5). In five patients with cervical carcinoma, 11 C-choline PET/CT was performed before and after treatment that consisted of cisplatin infusion and subsequent radiotherapy. Standardized uptake value (SUV) was compared with unidimensional and volumetric measurements that were made on magnetic resonance images (MRI) before and after treatment. Based on PET/CT interpretations, the reviewers correctly classified tumor (T) stage in 8 patients (47%), nodes (N) stage in 21 patients (96%), metastasis (M) stage in 20 patients (91%), and tumor, nodes and metastasis (TNM) stage in 15 patients (88%). Tumor size, volume, and SUV decreased after treatment in five patients with cervical carcinoma. Using the Pearson correlation test, a significant correlation was found between the reduction rate of SUV and reduction rate of tumor volume. 11 C-choline PET/CT is an accurate means for the management of patients with uterine carcinoma. The combination of 11 C-choline PET/CT and MRI increases the accuracy of staging in patients with uterine carcinoma. (author)

Prenatal choline supplementation attenuates MK-801-induced deficits in memory, motor function, and hippocampal plasticity in adult male rats.

Science.gov (United States)

Nickerson, Chelsea A; Brown, Alexandra L; Yu, Waylin; Chun, Yoona; Glenn, Melissa J

2017-10-11

Choline is essential to the development and function of the central nervous system and supplemental choline during development is neuroprotective against a variety of insults, including neurotoxins like dizocilpine (MK-801). MK-801 is an NMDA receptor antagonist that is frequently used in rodent models of psychological disorders, particularly schizophrenia. At low doses, it causes cognitive impairments, and at higher doses it induces motor deficits, anhedonia, and neuronal degeneration. The primary goals of the present study were to investigate whether prenatal choline supplementation protects against the cognitive impairments, motor deficits, and neuropathologies that are precipitated by MK-801 administration in adulthood. Adult male Sprague-Dawley rats were fed a standard or supplemented choline diet prenatally. Using the novelty preference test of object recognition, we found that only prenatal standard-fed rats displayed memory consolidation deficits induced by low-dose MK-801 administered immediately following study of sample objects; all other groups, including prenatal choline supplemented rats given MK-801, showed intact memory. Following high-dose MK-801, prenatal choline supplementation significantly alleviated rats' motor response to MK-801, particularly ataxia. Using doublecortin and Ki67 to mark neurogenesis and cell division, respectively, in the hippocampus, we found that prenatal choline supplementation, in the face of MK-801 toxicity, protected against reduced hippocampal plasticity. Taken together, the current findings suggest that prenatal choline supplementation protects against a variety of behavioral and neural pathologies induced by the neurotoxin, MK-801. This research contributes to the growing body of evidence supporting the robust neuroprotective capacity of choline. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

Measurement of concentrations of whole blood levels of choline, betaine, and dimethylglycine and their relations to plasma levels.

Science.gov (United States)

Awwad, Hussain Mohamad; Kirsch, Susanne H; Geisel, Juergen; Obeid, Rima

2014-04-15

We aimed at developing a method for the measurement of choline and its metabolites in whole blood (WB). After an extraction step, quantification of choline, betaine, and dimethylglycine (DMG) was performed using ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). Plasma and WB metabolites were evaluated in a group of 61 elderly people. The calibration curves were linear (r(2)>0.997) for all compounds. The inter- and intra-assay coefficients of variation for all analytes were 90% and the relative matrix effect were ≤4.0%. The median concentrations of choline, betaine, and DMG were 11.3, 27.8, and 5.9μmol/L in plasma and 66.6, 165, and 13.7μmol/L in WB, respectively. There were positive correlations between WB and plasma markers; for choline (r=0.42), betaine (r=0.61), and DMG (r=0.56) (all p≤0.001). The concentrations of betaine in WB and plasma were significantly higher in men than in women. The concentrations of WB choline and DMG did not differ significantly according to sex. In conclusion, we have established a reliable method for measuring choline metabolites in WB. The concentrations of WB choline, betaine, and DMG seem to reflect intracellular concentrations of these metabolites. Copyright © 2014 Elsevier B.V. All rights reserved.

Early Cessation of Adenosine Diphosphate Receptor Inhibitors Among Acute Myocardial Infarction Patients Treated With Percutaneous Coronary Intervention

DEFF Research Database (Denmark)

Fosbøl, Emil L; Ju, Christine; Anstrom, Kevin J

2016-01-01

BACKGROUND: Guidelines recommend the use of adenosine diphosphate receptor inhibitor (ADPri) therapy for 1 year postacute myocardial infarction; yet, early cessation of therapy occurs frequently in clinical practice. METHODS AND RESULTS: We examined 11 858 acute myocardial infarction patients tre...

Influence of the temperature in the uranium (Vi) sorption in zirconium diphosphate

International Nuclear Information System (INIS)

Garcia G, N.; Solis, D.; Ordonez R, E.

2012-10-01

In the present work was evaluated the uranium (Vi) sorption at 10, 20, 30, 40 and 60 C on the zirconium diphosphate (ZrP 2 O 7 ). They were carried out kinetic and isotherms using the method by lots, these will allow to fix the sorption time (kinetic) and to explain the behavior of this sorption in different ph conditions and temperature (isotherm). The quantity of retained uranium in the surface was quantified by means of the fluorescence technique. (Author)

Acquisition of Genetic Aberrations by Activation-Induced Cytidine Deaminase (AID) during Inflammation-Associated Carcinogenesis

International Nuclear Information System (INIS)

Takai, Atsushi; Marusawa, Hiroyuki; Chiba, Tsutomu

2011-01-01

Genetic abnormalities such as nucleotide alterations and chromosomal disorders that accumulate in various tumor-related genes have an important role in cancer development. The precise mechanism of the acquisition of genetic aberrations, however, remains unclear. Activation-induced cytidine deaminase (AID), a nucleotide editing enzyme, is essential for the diversification of antibody production. AID is expressed only in activated B lymphocytes under physiologic conditions and induces somatic hypermutation and class switch recombination in immunoglobulin genes. Inflammation leads to aberrant AID expression in various gastrointestinal organs and increased AID expression contributes to cancer development by inducing genetic alterations in epithelial cells. Studies of how AID induces genetic disorders are expected to elucidate the mechanism of inflammation-associated carcinogenesis

Prostate cancer: concordance between "1"8F-choline PET and CT in biochemical relapse

International Nuclear Information System (INIS)

Herández Pinzón, J.; Ferrarotti, C.; Ferrari, L.; Larrañaga, N.; Gallo, J.C.; Mena, D.; Bastianello, M.

2016-01-01

Objective: To establish the concordance between 18-fluor choline positron emission tomography (PET) and computed tomography (CT) for re-staging patients with biochemical relapse of prostate cancer according to the TNM system. Materials and methods: The medical records of the Molecular Imaging Section were retrospectively reviewed. The TNM classification was established by us for each method, and the Kappa concordance statistic was used to classify the results according to the Landis and Koch proposal. Results: The PET-choline reported 19 (59.4%) patients N0 and 13 (40.6%) N1, while CT reported 28 (87.5%) N0 and 4 (12.5%) N1. In metastasis classification PET-choline established M0 in 17 (53.1%) patients, M1a in 1 (3.1%), M1b in 5 (15.6%), M1c in 1 (3.1%), M1a + M1b in 7 (21.9%), and M1b + M1c in 1 (3.1%). On the other hand, CT was M0 in 23 (71.9%) patients, M1a in 2 (6.25%), M1a + M1b in 2 (6.25%), and M1b + M1c in 5 (15.6%). The correlation between PET-choline and CT in the TNM lymph node and metastasis classifications was 71.88%, with a Kappa of 0.3455 (standard error 0.1336; P=.0049) and 62.5% with Kappa 0.3725 (standard error 0.0847; P=.0001), respectively. Discussion: Several studies have shown a high diagnostic accuracy of PET-choline detecting the spread of the disease compared to conventional methods. Conclusion: There is poor concordance for metastatic and lymph node classifications according to the TNM system between choline-PET and CT. (authors) [es

Isolation and characterization of a copalyl diphosphate synthase gene promoter from Salvia miltiorrhiza

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Piotr Szymczyk

2016-09-01

Full Text Available The promoter, 5' UTR, and 34-nt 5' fragments of protein encoding region of the Salvia miltiorrhiza copalyl diphosphate synthase gene were cloned and characterized. No tandem repeats, miRNA binding sites, or CpNpG islands were observed in the promoter, 5' UTR, or protein encoding fragments. The entire isolated promoter and 5' UTR is 2235 bp long and contains repetitions of many cis-active elements, recognized by homologous transcription factors, found in Arabidopsis thaliana and other plant species. A pyrimidine-rich fragment with only 6 non-pyrimidine bases was localized in the 33-nt stretch from nt 2185 to 2217 in the 5' UTR. The observed cis-active sequences are potential binding sites for trans-factors that could regulate spatio-temporal CPS gene expression in response to biotic and abiotic stress conditions. Obtained results are initially verified by in silico and co-expression studies based on A. thaliana microarray data. The quantitative RT-PCR analysis confirmed that the entire 2269-bp copalyl diphosphate synthase gene fragment has the promoter activity. Quantitative RT-PCR analysis was used to study changes in CPS promoter activity occurring in response to the application of four selected biotic and abiotic regulatory factors; auxin, gibberellin, salicylic acid, and high-salt concentration.

Catalytic Conversion of Carbohydrates to Furanic Derivatives in the Presence of Choline Chloride

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François Jérôme

2017-07-01

Full Text Available The synthesis of furanic derivatives (5-hydroxymethylfurfural (HMF, furfural… from carbohydrates is of high interest for a wide range of applications. These reactions are carried out in the presence of various solvents, and among them choline chloride can be used. It is a salt that can form a low melting mixture with a carbohydrate (fructose, glucose… or a deep eutectic mixture with carboxylic acid. A review of the studies performed in the conversion of carbohydrates to furanic derivatives in the presence of choline chloride is presented here with the advantages and drawbacks of this solvent. Choline chloride can enhance the selectivity to HMF by stabilizing effect and allows the conversion of highly concentrated feed. However, the extraction of the products from these solvents still needs improvement.

Ag(I)-mediated homo and hetero pairs of guanosine and cytidine: monitoring by circular dichroism spectroscopy.

Science.gov (United States)

Goncharova, Iryna

2014-01-24

Ag(I)-containing compounds are attractive as antibacterial and antifungal agents. The renewed interest in the application of silver(I) compounds has led to the need for detailed knowledge of the mechanism of their action. One of the possible ways is the coordination of Ag(I) to G-C pairs of DNA, where Ag(+) ions form Ag(I)-mediated base pairs and inhibit the transcription. Herein, a systematic chiroptical study on silver(I)-mediated homo and mixed pairs of the C-G complementary-base derivatives cytidine(C) and 5'-guanosine monophosphate(G) in water is presented. Ag(I)-mediated homo and hetero pairs of G and C and their self-assembled species were studied under two pH levels (7.0 and 10.0) by vibrational (VCD) and electronic circular dichroism(ECD). VCD was used for the first time in this field and showed itself to be a powerful method for obtaining specific structural information in solution. Based on results of the VCD experiments, the different geometries of the homo pairs were proposed under pH 7.0 and 10.0. ECD was used as a diagnostic tool to characterize the studied systems and as a contact point between the previously defined structures of the metal or proton mediated pairs of nucleobases and the systems studied here. On the basis of the obtained data, the formation of the self-assembled species of cytidine with a structure similar to the i-motif structure in DNA was proposed at pH 10.0. Copyright © 2013 Elsevier B.V. All rights reserved.

Factors influencing erythrocyte choline concentrations.

Science.gov (United States)

Miller, B L; Jenden, D J; Tang, C; Read, S

1989-01-01

Choline concentrations in human erythrocytes increase after freezing and thawing, during incubation in Krebs-phosphate for 30 min or on storage at 0 degrees C for 3-24 hr. The increase is prevented by protein precipitation by 10% perchloric acid, 10% zinc hydroxide, 10% sodium tungstate or boiling in water. It is not prevented by EDTA (10 mM) and is increased by oleate (5 mM). We suggest that the increase is due to the action of phospholipase D on erythrocyte phospholipids.

Chronic alcoholism in rats induces a compensatory response, preserving brain thiamine diphosphate, but the brain 2-oxo acid dehydrogenases are inactivated despite unchanged coenzyme levels.

Science.gov (United States)

Parkhomenko, Yulia M; Kudryavtsev, Pavel A; Pylypchuk, Svetlana Yu; Chekhivska, Lilia I; Stepanenko, Svetlana P; Sergiichuk, Andrej A; Bunik, Victoria I

2011-06-01

Thiamine-dependent changes in alcoholic brain were studied using a rat model. Brain thiamine and its mono- and diphosphates were not reduced after 20 weeks of alcohol exposure. However, alcoholism increased both synaptosomal thiamine uptake and thiamine diphosphate synthesis in brain, pointing to mechanisms preserving thiamine diphosphate in the alcoholic brain. In spite of the unchanged level of the coenzyme thiamine diphosphate, activities of the mitochondrial 2-oxoglutarate and pyruvate dehydrogenase complexes decreased in alcoholic brain. The inactivation of pyruvate dehydrogenase complex was caused by its increased phosphorylation. The inactivation of 2-oxoglutarate dehydrogenase complex (OGDHC) correlated with a decrease in free thiols resulting from an elevation of reactive oxygen species. Abstinence from alcohol following exposure to alcohol reactivated OGDHC along with restoration of the free thiol content. However, restoration of enzyme activity occurred before normalization of reactive oxygen species levels. Hence, the redox status of cellular thiols mediates the action of oxidative stress on OGDHC in alcoholic brain. As a result, upon chronic alcohol consumption, physiological mechanisms to counteract the thiamine deficiency and silence pyruvate dehydrogenase are activated in rat brain, whereas OGDHC is inactivated due to impaired antioxidant ability. © 2011 The Authors. Journal of Neurochemistry © 2011 International Society for Neurochemistry.

Eight weeks of citicoline treatment does not perturb sleep/wake cycles in cocaine-dependent adults.

Science.gov (United States)

Bracken, Bethany K; Penetar, David M; Rodolico, John; Ryan, Elizabeth T; Lukas, Scott E

2011-06-01

Citicoline (cytidine-5'-diphosphate) is a mononucleotide composed of ribose, cytosine, pyrophosphate, and choline, and is involved in the biosynthesis of the structural phosopholipids of cell membranes. Treatment with citicoline, improves memory in patients with dementia, and reduces damage to the brain after traumatic brain injury or stroke. Recent research has been conducted to assess whether citicoline is an effective treatment for cocaine dependence. In cocaine-dependent individuals, withdrawal from cocaine is associated with disturbed sleep, which may contribute to the high rate of relapse to cocaine use. Therefore, it is important to know the impact of citicoline on the sleep/wake cycle in these individuals in order to rate its overall efficacy. In this double-blind, placebo-controlled trial, the effects of citicoline treatment on the sleep/wake cycles of cocaine dependent participants were assessed. The results of the current study are reported as part of a larger study, consisting of an eight-week treatment period to assess the efficacy of longer-term treatment with citicoline at decreasing cocaine consumption in cocaine-dependent polydrug using participants. In this non-abstinent, cocaine-dependent population, citicoline had no effect on any of the sleep parameters measured including sleep efficiency, sleep latency, total sleep time, number of waking episodes, time awake per episode, amount of time in bed spent moving, number of sleep episodes, time asleep per episode, and amount of time in bed spent immobile. These data suggest that eight weeks of citicoline administration does not disturb sleep/wake cycles of cocaine-dependent individuals. Copyright © 2011 Elsevier Inc. All rights reserved.

Effect of CDP-choline on the biosynthesis of phospholipids in brain regions during hypoxic treatment

International Nuclear Information System (INIS)

Alberghina, M.; Viola, M.; Serra, I.; Mistretta, A.; Giuffrida, A.M.

1981-01-01

Acute administration of CDP-choline (i.p. 100 mg/Kg b.w.), 10 min before the intraventricular injection of labeled precursors, [2-3H] glycerol and [1-14C]-palmitate, was able to correct the impairment caused by hypoxic treatment of lipid metabolism in some brain regions, ie, cerebral hemispheres, cerebellum, and brainstem. After CDP-choline treatment, an increase of the specific radioactivity of total lipids and of phospholipids was observed in mitochondria purified from the three above-mentioned brain regions of the hypoxic animals, while no effect on the other subcellular fractions was found. CDP-Choline had a stimulating effect particularly on the incorporation of both precursors into mitochondrial PC, PE, and polyglycerophosphatides isolated form the three brain regions examined. The results obtained show that the action of CDP-choline in restoring lipid metabolism was more pronounced in brain mitochondria, which, among subcellular fractions, were the most affected by the hypoxic treatment

Comparable stability of Hoogsteen and Watson-Crick base pairs in ionic liquid choline dihydrogen phosphate.

Science.gov (United States)

Tateishi-Karimata, Hisae; Nakano, Miki; Sugimoto, Naoki

2014-01-08

The instability of Hoogsteen base pairs relative to Watson-Crick base pairs has limited biological applications of triplex-forming oligonucleotides. Hydrated ionic liquids (ILs) provide favourable environments for a wide range of chemical reactions and are known to impact the stabilities of Watson-Crick base pairs. We found that DNA triplex formation was significantly stabilized in hydrated choline dihydrogen phosphate as compared with an aqueous buffer at neutral pH. Interestingly, the stability of Hoogsteen base pairs was found to be comparable with that of Watson-Crick base pairs in the hydrated IL. Molecular dynamics simulations of a DNA triplex in the presence of choline ions revealed that the DNA triplex was stabilized because of the binding of choline ion around the third strand in the grooves. Our finding will facilitate the development of new DNA materials. Our data also indicate that triplex formation may be stabilized inside cells where choline ions and their derivatives are abundant in vivo.

Comparable Stability of Hoogsteen and Watson–Crick Base Pairs in Ionic Liquid Choline Dihydrogen Phosphate

Science.gov (United States)

Tateishi-Karimata, Hisae; Nakano, Miki; Sugimoto, Naoki

2014-01-01

The instability of Hoogsteen base pairs relative to Watson–Crick base pairs has limited biological applications of triplex-forming oligonucleotides. Hydrated ionic liquids (ILs) provide favourable environments for a wide range of chemical reactions and are known to impact the stabilities of Watson–Crick base pairs. We found that DNA triplex formation was significantly stabilized in hydrated choline dihydrogen phosphate as compared with an aqueous buffer at neutral pH. Interestingly, the stability of Hoogsteen base pairs was found to be comparable with that of Watson–Crick base pairs in the hydrated IL. Molecular dynamics simulations of a DNA triplex in the presence of choline ions revealed that the DNA triplex was stabilized because of the binding of choline ion around the third strand in the grooves. Our finding will facilitate the development of new DNA materials. Our data also indicate that triplex formation may be stabilized inside cells where choline ions and their derivatives are abundant in vivo. PMID:24399194

Studies on the riboflavin, pantothenic acid, nicotinic acid and choline requirements of young Embden geese

Science.gov (United States)

Serafin, J.A.

1981-01-01

Four experiments were conducted to examine the riboflavin, pantothenic acid, nicotinic acid, and choline requirements of young Embden geese fed purified diets. Goslings fed diets deficient in either riboflavin, pantothenic acid, nicotinic acid, or choline grew poorly. Feeding a pantothenic acid-deficient diet resulted in 100% mortality. Goslings fed diets containing 530 mg/kg of choline or less developed perosis. Under the conditions of these experiments it was found that: 1) goslings require no more than 3.84 mg/kg of riboflavin and 31.2 mg/kg of nicotinic acid in the diet for rapid growth and normal development, 2) the pantothenic acid requirement of goslings is no more than 12.6 mg/kg of diet, and 3) a dietary choline level of 1530 mg/kg is adequate for both the prevention of perosis and rapid growth of goslings. The levels of vitamins found to support normal growth and development of goslings appear to be similar to requirements of other species that have been examined.

Value of {sup 11}C-choline PET and PET/CT in patients with suspected prostate cancer

Energy Technology Data Exchange (ETDEWEB)

Scher, Bernhard; Albinger, Wolfram; Tiling, Reinhold; Gildehaus, Franz-Josef; Dresel, Stefan [University of Munich, Department of Nuclear Medicine, Munich (Germany); Seitz, Michael [University of Munich, Department of Urology, Munich (Germany); Scherr, Michael; Becker, Hans-Christoph [University of Munich, Department of Radiology, Munich (Germany); Souvatzogluou, Michael; Wester, Hans-Juergen [Technical University of Munich, Department of Nuclear Medicine, Munich (Germany)

2007-01-15

The value and limitations of {sup 11}C-choline PET and PET/CT for the detection of prostate cancer remain controversial. The aim of this study was to investigate the diagnostic efficacy of {sup 11}C-choline PET and PET/CT in a large group of patients with suspected prostate cancer. Fifty-eight patients with clinical suspicion of prostate cancer underwent {sup 11}C-choline PET (25/58, Siemens ECAT Exact HR+) or PET/CT (33/58, Philips Gemini) scanning. On average, 500 MBq of {sup 11}C-choline was administered intravenously. Studies were interpreted by raters blinded to clinical information and other diagnostic procedures. Qualitative image analysis as well as semiquantitative SUV measurement was carried out. The reference standard was histopathological examination of resection specimens or biopsy. Prevalence of prostate cancer in this selected patient population was 63.8% (37/58). {sup 11}C-choline PET and PET/CT showed a sensitivity of 86.5% (32/37) and a specificity of 61.9% (13/21) in the detection of the primary malignancy. With regard to metastatic spread, PET showed a per-patient sensitivity of 81.8% (9/11) and produced no false positive findings. Based on our findings, differentiation between benign prostatic changes, such as benign prostatic hyperplasia or prostatitis, and prostate cancer is feasible in the majority of cases when image interpretation is primarily based on qualitative characteristics. SUV{sub max} may serve as guidance. False positive findings may occur due to an overlap of {sup 11}C-choline uptake between benign and malignant processes. By providing functional information regarding both the primary malignancy and its metastases, {sup 11}C-choline PET may prove to be a useful method for staging prostate cancer. (orig.)

Crystal structure of CbpF, a bifunctional choline-binding protein and autolysis regulator from Streptococcus pneumoniae.

Science.gov (United States)

Molina, Rafael; González, Ana; Stelter, Meike; Pérez-Dorado, Inmaculada; Kahn, Richard; Morales, María; Moscoso, Miriam; Campuzano, Susana; Campillo, Nuria E; Mobashery, Shahriar; García, José L; García, Pedro; Hermoso, Juan A

2009-03-01

Phosphorylcholine, a crucial component of the pneumococcal cell wall, is essential in bacterial physiology and in human pathogenesis because it binds to serum components of the immune system and acts as a docking station for the family of surface choline-binding proteins. The three-dimensional structure of choline-binding protein F (CbpF), one of the most abundant proteins in the pneumococcal cell wall, has been solved in complex with choline. CbpF shows a new modular structure composed both of consensus and non-consensus choline-binding repeats, distributed along its length, which markedly alter its shape, charge distribution and binding ability, and organizing the protein into two well-defined modules. The carboxy-terminal module is involved in cell wall binding and the amino-terminal module is crucial for inhibition of the autolytic LytC muramidase, providing a regulatory function for pneumococcal autolysis.

Loss of P53 Function in Colon Cancer Cells Results in Increased Phosphocholine and Total Choline

Directory of Open Access Journals (Sweden)

Noriko Mori

2004-10-01

Full Text Available Mutations in the p53 gene are the most frequently observed genetic lesions in human cancers. Human cancers that contain a p53 mutation are more aggressive, more apt to metastasize, and more often fatal. p53 controls numerous downstream targets that can influence various outcomes such as apoptosis, growth arrest, and DNA repair. Based on previous observations using 1H magnetic resonance spectroscopy (MRS, we have identified choline phospholipid metabolite intensities typical of increased malignancy. Here we have used 1H MRS to characterize the choline phospholipid metabolite levels of p53+/+ and p53−/– cells, and demonstrated that loss of p53 function results in increased phosphocholine and total choline. These data suggest that the increased malignancy of cancer cells resulting from loss of p53 may be mediated, in part, through the choline phospholipid pathway.

Editor's Highlight: Perfluorooctane Sulfonate-Choline Ion Pair Formation: A Potential Mechanism Modulating Hepatic Steatosis and Oxidative Stress in Mice.

Science.gov (United States)

Zhang, Limin; Krishnan, Prasad; Ehresman, David J; Smith, Philip B; Dutta, Mainak; Bagley, Bradford D; Chang, Shu-Ching; Butenhoff, John L; Patterson, Andrew D; Peters, Jeffrey M

2016-09-01

The mechanisms underlying perfluorooctane sulfonate (PFOS)-induced steatosis remain unclear. The hypothesis that PFOS causes steatosis and other hepatic effects by forming an ion pair with choline was examined. C57BL/6 mice were fed either a control diet or a marginal methionine/choline-deficient (mMCD) diet, with and without 0.003, 0.006, or 0.012% potassium PFOS. Dietary PFOS caused a dose-dependent decrease in body weight, and increases in the relative liver weight, hepatic triglyceride concentration and serum markers of liver toxicity and oxidative stress. Some of these effects were exacerbated in mice fed the mMCD diet supplemented with 0.012% PFOS compared with those fed the control diet supplemented with 0.012% PFOS. Surprisingly, serum PFOS concentrations were higher while liver PFOS concentrations were lower in mMCD-fed mice compared with corresponding control-fed mice. To determine if supplemental dietary choline could prevent PFOS-induced hepatic effects, C57BL/6 mice were fed a control diet, or a choline supplemental diet (1.2%) with or without 0.003% PFOS. Lipidomic analysis demonstrated that PFOS caused alterations in hepatic lipid metabolism in the PFOS-fed mice compared with controls, and supplemental dietary choline prevented these PFOS-induced changes. Interestingly, dietary choline supplementation also prevented PFOS-induced oxidative damage. These studies are the first to suggest that PFOS may cause hepatic steatosis and oxidative stress by effectively reducing the choline required for hepatic VLDL production and export by forming an ion pair with choline, and suggest that choline supplementation may prevent and/or treat PFOS-induced hepatic steatosis and oxidative stress. © The Author 2016. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Choline-based biodegradable ionic liquid catalyst for Mannich-type

Indian Academy of Sciences (India)

Choline-based biodegradable ionic liquid catalyst for Mannich-type reaction ... Abstract. A three-component Mannich-type reaction of aromatic aldehydes, ketones, and amines was catalyzed by a novel ... Journal of Chemical Sciences | News.

Molecular Effects of Doxorubicin on Choline Metabolism in Breast Cancer

Directory of Open Access Journals (Sweden)

Menglin Cheng

2017-08-01

Full Text Available Abnormal choline phospholipid metabolism is a hallmark of cancer. The magnetic resonance spectroscopy (MRS detected total choline (tCho signal can serve as an early noninvasive imaging biomarker of chemotherapy response in breast cancer. We have quantified the individual components of the tCho signal, glycerophosphocholine (GPC, phosphocholine (PC and free choline (Cho, before and after treatment with the commonly used chemotherapeutic drug doxorubicin in weakly metastatic human MCF7 and triple-negative human MDA-MB-231 breast cancer cells. While the tCho concentration did not change following doxorubicin treatment, GPC significantly increased and PC decreased. Of the two phosphatidylcholine-specific PLD enzymes, only PLD1, but not PLD2, mRNA was down-regulated by doxorubicin treatment. For the two reported genes encoding GPC phosphodiesterase, the mRNA of GDPD6, but not GDPD5, decreased following doxorubicin treatment. mRNA levels of choline kinase α (ChKα, which converts Cho to PC, were reduced following doxorubicin treatment. PLD1 and ChKα protein levels decreased following doxorubicin treatment in a concentration dependent manner. Treatment with the PLD1 specific inhibitor VU0155069 sensitized MCF7 and MDA-MB-231 breast cancer cells to doxorubicin-induced cytotoxicity. Low concentrations of 100 nM of doxorubicin increased MDA-MB-231 cell migration. GDPD6, but not PLD1 or ChKα, silencing by siRNA abolished doxorubicin-induced breast cancer cell migration. Doxorubicin induced GPC increase and PC decrease are caused by reductions in PLD1, GDPD6, and ChKα mRNA and protein expression. We have shown that silencing or inhibiting these genes/proteins can promote drug effectiveness and reduce adverse drug effects. Our findings emphasize the importance of detecting PC and GPC individually.

Choline status and neurodevelopmental outcomes at 5 years of age in the Seychelles Child Development Nutrition Study.

Science.gov (United States)

Strain, J J; McSorley, Emeir M; van Wijngaarden, Edwin; Kobrosly, Roni W; Bonham, Maxine P; Mulhern, Maria S; McAfee, Alison J; Davidson, Philip W; Shamlaye, Conrad F; Henderson, Juliette; Watson, Gene E; Thurston, Sally W; Wallace, Julie M W; Ueland, Per M; Myers, Gary J

2013-07-28

Choline is an essential nutrient that is found in many food sources and plays a critical role in the development of the central nervous system. Animal studies have shown that choline status pre- and postnatally can have long-lasting effects on attention and memory; however, effects in human subjects have not been well studied. The aim of the present study was to examine the association between plasma concentrations of free choline and its related metabolites in children and their neurodevelopment in the Seychelles Child Development Nutrition Study, an ongoing longitudinal study assessing the development of children born to mothers with high fish consumption during pregnancy. Plasma concentrations of free choline, betaine, dimethylglycine (DMG), methionine and homocysteine and specific measures of neurodevelopment were measured in 210 children aged 5 years. The children's plasma free choline concentration (9·17 (sd 2·09) μmol/l) was moderately, but significantly, correlated with betaine (r 0·24; P= 0·0006), DMG (r 0·15; P= 0·03), methionine (r 0·24; P= 0·0005) and homocysteine (r 0·19; P= 0·006) concentrations. Adjusted multiple linear regression revealed that betaine concentrations were positively associated with Preschool Language Scale – total language scores (β = 0·066; P= 0·04), but no other associations were evident. We found no indication that free choline concentration or its metabolites, within the normal physiological range, are associated with neurodevelopmental outcomes in children at 5 years of age. As there is considerable animal evidence suggesting that choline status during development is associated with cognitive outcome, the issue deserves further study in other cohorts.

Choline kinase-alpha by regulating cell aggressiveness and drug sensitivity is a potential druggable target for ovarian cancer

OpenAIRE

Granata, A; Nicoletti, R; Tinaglia, V; De Cecco, L; Pisanu, M E; Ricci, A; Podo, F; Canevari, S; Iorio, E; Bagnoli, M; Mezzanzanica, D

2013-01-01

Background: Aberrant choline metabolism has been proposed as a novel cancer hallmark. We recently showed that epithelial ovarian cancer (EOC) possesses an altered MRS-choline profile, characterised by increased phosphocholine (PCho) content to which mainly contribute over-expression and activation of choline kinase-alpha (ChoK-alpha). Methods: To assess its biological relevance, ChoK-alpha expression was downmodulated by transient RNA interference in EOC in vitro models. Gene expression profi...

A Facile, Choline Chloride/Urea Catalyzed Solid Phase Synthesis of Coumarins via Knoevenagel Condensation

Directory of Open Access Journals (Sweden)

Hosanagara N. Harishkumar

2011-01-01

Full Text Available The influence of choline chloride/urea ionic liquid in solid phase on the Knoevenagel condensation is demonstrated. The active methylene compounds such as meldrum’s acid, diethylmalonate, ethyl cyanoacetate, dimethylmalonate, were efficiently condensed with various salicylaldehydes in presence of choline chloride/urea ionic liquid without using any solvents or additional catalyst. The reaction is remarkably facile because of the air and water stability of the catalyst, and needs no special precautions. The reactions were completed within 1hr with excellent yields (95%. The products formed were sufficiently pure, and can be easily recovered. The use of ionic liquid choline chloride/urea in solid phase offered several significant advantages such as low cost, greater selectivity and easy isolation of products.

Phosphoribosyl diphosphate synthetase-independent NAD de novo synthesis in Escherichia coli: a new phenotype of phosphate regulon mutants

DEFF Research Database (Denmark)

Hove-Jensen, Bjarne

1996-01-01

Phosphoribosyl diphosphate-lacking (Δprs) mutant strains of Escherichia coli require NAD, guanosine, uridine, histidine, and tryptophan for growth. NAD is required by phosphoribosyl diphosphate-lacking mutants because of lack of one of the substrates for the quinolinate phosphoribosyltransferase...... reaction, an enzyme of the NAD de novo pathway. Several NAD-independent mutants of a host from which prs had been deleted were isolated; all of them were shown to have lesions in the pstSCAB-phoU operon, in which mutations lead to derepression of the Pho regulon. In addition NAD-independent growth...... was dependent on a functional quinolinate phosphoribosyltransferase. The prs suppressor mutations led to the synthesis of a new phosphoryl compound that may act as a precursor for a new NAD biosynthetic pathway. This compound may be synthesized by the product of an unknown phosphate starvation-inducible gene...

Choline and its metabolites are differently associated with cardiometabolic risk factors, cardiovascular history and MRI documented cerebrovascular disease in older adults

Science.gov (United States)

Background: There is a potential role of choline in cardiovascular and cerebrovascular disease through its involvement in lipid and one-carbon metabolism. Objective: We evaluated the associations of plasma choline and choline-related compounds with cardiometabolic risk factors, history of cardiovas...

Bronsted acid-functionalized choline chloride-butane sultone for the ...

Indian Academy of Sciences (India)

M P PADMA PRIYA

2018-03-21

Mar 21, 2018 ... Choline chloride and 1,4-butane sultone were combined to obtain a sulphonic acid-functionalized ..... Knifton J F and Sanderson J R 1990 Method for produc- ... alkenes via the Knoevenagel condensation Tetrahedron. Lett.

Choline PET based dose-painting in prostate cancer - Modelling of dose effects

International Nuclear Information System (INIS)

Niyazi, Maximilian; Bartenstein, Peter; Belka, Claus; Ganswindt, Ute

2010-01-01

Several randomized trials have documented the value of radiation dose escalation in patients with prostate cancer, especially in patients with intermediate risk profile. Up to now dose escalation is usually applied to the whole prostate. IMRT and related techniques currently allow for dose escalation in sub-volumes of the organ. However, the sensitivity of the imaging modality and the fact that small islands of cancer are often dispersed within the whole organ may limit these approaches with regard to a clear clinical benefit. In order to assess potential effects of a dose escalation in certain sub-volumes based on choline PET imaging a mathematical dose-response model was developed. Based on different assumptions for α/β, γ50, sensitivity and specificity of choline PET, the influence of the whole prostate and simultaneous integrated boost (SIB) dose on tumor control probability (TCP) was calculated. Based on the given heterogeneity of all potential variables certain representative permutations of the parameters were chosen and, subsequently, the influence on TCP was assessed. Using schedules with 74 Gy within the whole prostate and a SIB dose of 90 Gy the TCP increase ranged from 23.1% (high detection rate of choline PET, low whole prostate dose, high γ50/ASTRO definition for tumor control) to 1.4% TCP gain (low sensitivity of PET, high whole prostate dose, CN + 2 definition for tumor control) or even 0% in selected cases. The corresponding initial TCP values without integrated boost ranged from 67.3% to 100%. According to a large data set of intermediate-risk prostate cancer patients the resulting TCP gains ranged from 22.2% to 10.1% (ASTRO definition) or from 13.2% to 6.0% (CN + 2 definition). Although a simplified mathematical model was employed, the presented model allows for an estimation in how far given schedules are relevant for clinical practice. However, the benefit of a SIB based on choline PET seems less than intuitively expected. Only under the

Dietary folate and choline status differentially affect lipid metabolism and behavior-mediated neurotransmitters in young rats

Science.gov (United States)

The relationship between choline and folate metabolisms is an important issue due to the essential role of these nutrients in brain plasticity and cognitive functions. Present study was designed to investigate whether modification of the dietary folate-choline status in young rats would affect brain...

Effect of addition of Proline, ionic liquid [Choline][Pro] on CO2 separation properties of poly(amidoamine) dendrimer / poly(ethylene glycol) hybrid membranes

Science.gov (United States)

Duan, S. H.; Kai, T.; Chowdhury, F. A.; Taniguchi, I.; Kazama, S.

2018-01-01

Poly(amidoamine) (PAMAM) dendrimers were incorporated into cross-linked poly(ethylene glycol) (PEGDMA) matrix to improve carbon dioxide (CO2) separation performance at elevated pressures. In our previous studies, PAMAM/PEGDMA hybrid membranes showed high CO2 separation properties from CO2/H2 mixed gases. In this study, proline, choline and ionic liquid [Choline][Pro] compounds were selected as rate promoters that were used to prepare PAMAM/PEGDMA hybrid membranes. The effect of addition of proline, choline, IL [Choline][Pro] on separation performance of PAMAM/PEGDMA) hybrid membranes for CO2/H2 separation was investigated. Amino acid proline, choline, and IL [Choline][Pro] were used to promote CO2 and amine reaction. With the addition of [Choline][Pro] into PAMAM/PEG membrane, CO2 permeance of PAMAM/PEG hybrid membranes are increased up to 46% without any change of selectivity of membrane for CO2.

Synthesis and study of thiocarbonate derivatives of choline as potential inhibitors of acetylcholinesterase.

Science.gov (United States)

Boyle, N A; Talesa, V; Giovannini, E; Rosi, G; Norton, S J

1997-09-12

Fourteen alkyl and aryl thiocarbonate derivatives of choline were synthesized and studied as potential inhibitors of acetylcholinesterase (AChE). Twelve of the compounds inhibited AChEs derived from calf forebrain, human red blood cells, and octopus brain ranging from low to moderately high inhibition potency. The concentration of each inhibitory compound giving 50% inhibition of enzyme activity (IC50 values, which ranged from 1 x 10(-2) to 8 x 10(-7) M) was determined and is reported; inhibitor constants (Ki values) for the most inhibitory compounds, (1-pentylthiocarbonyl)choline chloride and (1-heptylthiocarbonyl)choline chloride, were calculated from kinetic data and are also reported. The inhibitors are competitive with substrate, and they are not hydrolyzed by the AChE activities. Certain of these new compounds may provide direction for the development of new drugs that have anticholinesterase activity and may be used for the treatment of Alzheimer's disease.

Functional characterization of ent-copalyl diphosphate synthase from Andrographis paniculata with putative involvement in andrographolides biosynthesis.

Science.gov (United States)

Shen, Qinqin; Li, Lixia; Jiang, Yu; Wang, Qiang

2016-01-01

To characterize the ent-copalyl diphosphate (ent-CPP) synthase involved in the biosynthetic pathway of andrographolides in a medicinal plant, Andrographis paniculata. The ent-CPP synthase (ent-CPS) gene was cloned from A. paniculata and its encoded ApCPS was demonstrated to react with (E,E,E)-geranylgeranyl diphosphate to form ent-CPP through recombinant expression in Escherichia coli. Site-directed mutagenesis of the Asp to Ala in the conserved DXDD motif of ApCPS resulted in loss of function. One Arg is located in the conserved position close to DXDD motif indicating the involvement of ApCPS in specialized metabolism. In addition, RT-PCR analysis revealed that ApCPS was expressed in all tissues of A. paniculata at all growth stages, which is consistent with andrographolides accumulating in these organs. Methyl jasmonate induced ApCPS gene expression, matching inducible accumulation of andrographolides in vivo. ApCPS is the first ent-CPS characterized in A. paniculata and is suggested to be involved in biosynthesis of andrographolides that have high pharmaceutical values.

Overexpression of Farnesyl Diphosphate Synthase in Arabidopsis Mitochondria Triggers Light-dependent Lesion Formation and Alters Cytokinin Homeostasis

Czech Academy of Sciences Publication Activity Database

Manzano, D.; Busquets, A.; Closa, M.; Hoyerová, Klára; Schaller, H.; Kamínek, Miroslav; Arró, M.; Ferrer, A.

2006-01-01

Roč. 61, 1-2 (2006), s. 195-213 ISSN 0167-4412 R&D Projects: GA AV ČR(CZ) IAA600380507 Institutional research plan: CEZ:AV0Z50380511 Keywords : Arabidopsis thaliana * cytokinin * farnesyl diphosphate synthase * isoprenoid Subject RIV: EF - Botanics Impact factor: 3.577, year: 2006

3D-segmentation of the 18F-choline PET signal for target volume definition in radiation therapy of the prostate.

Science.gov (United States)

Ciernik, I Frank; Brown, Derek W; Schmid, Daniel; Hany, Thomas; Egli, Peter; Davis, J Bernard

2007-02-01

Volumetric assessment of PET signals becomes increasingly relevant for radiotherapy (RT) planning. Here, we investigate the utility of 18F-choline PET signals to serve as a structure for semi-automatic segmentation for forward treatment planning of prostate cancer. 18F-choline PET and CT scans of ten patients with histologically proven prostate cancer without extracapsular growth were acquired using a combined PET/CT scanner. Target volumes were manually delineated on CT images using standard software. Volumes were also obtained from 18F-choline PET images using an asymmetrical segmentation algorithm. PTVs were derived from CT 18F-choline PET based clinical target volumes (CTVs) by automatic expansion and comparative planning was performed. As a read-out for dose given to non-target structures, dose to the rectal wall was assessed. Planning target volumes (PTVs) derived from CT and 18F-choline PET yielded comparable results. Optimal matching of CT and 18F-choline PET derived volumes in the lateral and cranial-caudal directions was obtained using a background-subtracted signal thresholds of 23.0+/-2.6%. In antero-posterior direction, where adaptation compensating for rectal signal overflow was required, optimal matching was achieved with a threshold of 49.5+/-4.6%. 3D-conformal planning with CT or 18F-choline PET resulted in comparable doses to the rectal wall. Choline PET signals of the prostate provide adequate spatial information amendable to standardized asymmetrical region growing algorithms for PET-based target volume definition for external beam RT.

Correlation between 11C-choline or 18F-FDG uptake and tumor proliferation: a rabbit bearing lung cancer model study

International Nuclear Information System (INIS)

Li Yajun; Bai Renju; Gao Shuo; Li Yansheng; Liu Lei; Jia Wei; Cai Li; Xing Xiling

2009-01-01

Objective: Tumor proliferative activity has been recognized as an indicator of malignant degree in lung cancer and related to prognosis. The purpose of this study was to evaluate the feasibility of assessing proliferative activity with 11 C-choline and 18 F-fluorodeoxyglucose (FDG) PET on a rabbit bearing lung VX2 tumor model. Methods: About 0.5 ml of viable VX2 tumor cell suspension was slowly injected into the right lungs of 54 New Zealand white rabbits through a transthoracical needle insertion. 11 C-choline and 18 F-FDG PET scan were performed 10-11 d after tumor implantation. One ear vein was cannulated for administration of the tracers, 11 C-choline PET scan (with Discovery LS PET/CT scanner, GE) was performed 5 rain after intravenously injection of 37 MBq 11 C-choline. Then 18.7 MBq 18 F-FDG was infused at 60 min after 11 C-choline administration and 18 F-FDG PET scan was performed at 60 min after 18 F-FDG administration. The maximal standardized uptake value of tumor was calculated. The animals were euthanized after examination. Histochemical stain with proliferating cell nuclear antigen (PCNA) was performed and PCNA index was obtained to assess tumor proliferation. The difference of 11 C-choline and 18 F-FDG was analyzed using paired student t-test. The correlation of 11 C-choline 18 F-FDG and tumor cell density and PCNA index was analyzed using Pearson linear regression. Results: Of the 54 rabbits, 36 had a solitary pulmonary tumor. The rate of successful generation of a solitary VX2 tumor was 66.7% (36/54). Only 33 rabbits underwent both 11 C-choline and 18 F-FDG PET, and enrolled in this study. The mean cellular density was (547.36 ± 64.78) cells/field and the mean PCNA index was (42.34 ± 15.26)%. 18 F-FDG was higher than 11 C-choline (5.70 ± 3.45 vs 4.02 ± 3.07, t=-3.188, P=0.003). 11 C-choline significantly and positively correlated with PCNA index (r=0.786, P 11 C-choline and tumor cellular density (r=-0.176, P=0.327). 18 F-FDG significantly and

Enhancing the biodegradation of oil in sandy sediments with choline: A naturally methylated nitrogen compound

International Nuclear Information System (INIS)

Mortazavi, Behzad; Horel, Agota; Anders, Jennifer S.; Mirjafari, Arsalan; Beazley, Melanie J.; Sobecky, Patricia A.

2013-01-01

We investigated how additions of choline, a naturally occurring methylated nitrogen-containing compound, accelerated hydrocarbon degradation in sandy sediments contaminated with moderately weathered crude oil (4000 mg kg −1 sediment). Addition of lauroylcholine chloride (LCC) and tricholine citrate (TCC) to oil contaminated sediments resulted in 1.6 times higher hydrocarbon degradation rates compared to treatments without added choline derivatives. However, the degradation rate constant for the oil contaminated sediments amended with LCC was similar to that in contaminated sediments amended with inorganic nitrogen, phosphorus, and glucose. Additions of LLC and TCC to sediments containing extensively weathered oil also resulted in enhanced mineralization rates. Cultivation-free 16S rRNA analysis revealed the presence of an extant microbial community with clones closely related to known hydrocarbon degraders from the Gammaproteobacteria, Alphaproteobacteria, and Firmicutes phyla. The results demonstrate that the addition of minimal amounts of organic compounds to oil contaminated sediments enhances the degradation of hydrocarbons. -- Highlights: •Aerobic degradation of weathered crude oil in sandy sediments was determined. •The effect of input of choline on degradation rates was determined. •16S rRNA clone library analyses were used to examine the microbial phylogeny. •The bacterial community was consisted of clones related to hydrocarbon degraders. •Hydrocarbon degradation in sandy sediments was accelerated by addition of choline. -- Choline, a naturally occurring methylated nitrogen-containing compound, accelerated hydrocarbon degradation in sandy sediments by an extant microbial community

Application of 11C-choline PET/CT imaging for differentiating malignant from benign prostate lesions

International Nuclear Information System (INIS)

Li Xin; Wang Muwen; Liu Qingwei; Zhu Renjuan; Liu Lihui; Yuan Xianshun; Yao Shuzhan; Liu Songtao

2006-01-01

Objective: To investigate the potential of 11 C-choline PET/CT imaging for differentiating prostate cancer from benign prostate hyperplasia. Methods: A total of 45 patients with prostate lesions under- went 11 C-choline PET/CT imaging before transrectal needle biopsy. PET/CT imaging was performed 5 min after injection of 7.4 MBq/kg 11 C-choline in supine position over lower abdomen (3 min per bed with 2 beds), including the pelvis, and the whole body with 6 beds when necessary. After attenuation correction and iterative reconstruction, PET data were analyzed semi-quantitatively by measuring maximum standardized uptake values (SUV max ) in prostate lesions (P, target) and the muscles (M, non-target) and then P/M ratios were calculated. Also visual analysis was performed in different transverse, sagittal views and slices as well as three-dimensional images. Results: Eighteen prostate cancer and 27 benign prostate hyperplasia [and(or) chronic prostatitis] were all confirmed by pathology. The mean P/M ratio of prostate cancer was 4.02± 1.88, while in benign lesions was 1.87±1.21. The statistical differences of P/M ratios between them were significant (t=2.07, P 11 C-choline PET/CT imaging were 88.89%, 88.89% and 92.31% respectively. Conclusions: 11 C-choline PET/CT imaging is a valuable non-invasive technology in the diagnosis of pros- tate cancer. The P/M ratio can differentiate prostate cancer from benign lesions better than SUV. (authors)

Role of choline deficiency in the Fatty liver phenotype of mice fed a low protein, very low carbohydrate ketogenic diet.

Science.gov (United States)

Schugar, Rebecca C; Huang, Xiaojing; Moll, Ashley R; Brunt, Elizabeth M; Crawford, Peter A

2013-01-01

Though widely employed for clinical intervention in obesity, metabolic syndrome, seizure disorders and other neurodegenerative diseases, the mechanisms through which low carbohydrate ketogenic diets exert their ameliorative effects still remain to be elucidated. Rodent models have been used to identify the metabolic and physiologic alterations provoked by ketogenic diets. A commonly used rodent ketogenic diet (Bio-Serv F3666) that is very high in fat (~94% kcal), very low in carbohydrate (~1% kcal), low in protein (~5% kcal), and choline restricted (~300 mg/kg) provokes robust ketosis and weight loss in mice, but through unknown mechanisms, also causes significant hepatic steatosis, inflammation, and cellular injury. To understand the independent and synergistic roles of protein restriction and choline deficiency on the pleiotropic effects of rodent ketogenic diets, we studied four custom diets that differ only in protein (5% kcal vs. 10% kcal) and choline contents (300 mg/kg vs. 5 g/kg). C57BL/6J mice maintained on the two 5% kcal protein diets induced the most significant ketoses, which was only partially diminished by choline replacement. Choline restriction in the setting of 10% kcal protein also caused moderate ketosis and hepatic fat accumulation, which were again attenuated when choline was replete. Key effects of the 5% kcal protein diet - weight loss, hepatic fat accumulation, and mitochondrial ultrastructural disarray and bioenergetic dysfunction - were mitigated by choline repletion. These studies indicate that synergistic effects of protein restriction and choline deficiency influence integrated metabolism and hepatic pathology in mice when nutritional fat content is very high, and support the consideration of dietary choline content in ketogenic diet studies in rodents to limit hepatic mitochondrial dysfunction and fat accumulation.

A Trojan-Horse Peptide-Carboxymethyl-Cytidine Antibiotic from Bacillus amyloliquefaciens.

Science.gov (United States)

Serebryakova, Marina; Tsibulskaya, Darya; Mokina, Olga; Kulikovsky, Alexey; Nautiyal, Manesh; Van Aerschot, Arthur; Severinov, Konstantin; Dubiley, Svetlana

2016-12-07

Microcin C and related antibiotics are Trojan-horse peptide-adenylates. The peptide part is responsible for facilitated transport inside the sensitive cell, where it gets processed to release a toxic warhead-a nonhydrolyzable aspartyl-adenylate, which inhibits aspartyl-tRNA synthetase. Adenylation of peptide precursors is carried out by MccB THIF-type NAD/FAD adenylyltransferases. Here, we describe a novel microcin C-like compound from Bacillus amyloliquefaciens. The B. amyloliquefaciens MccB demonstrates an unprecedented ability to attach a terminal cytidine monophosphate to cognate precursor peptide in cellular and cell free systems. The cytosine moiety undergoes an additional modification-carboxymethylation-that is carried out by the C-terminal domain of MccB and the MccS enzyme that produces carboxy-SAM, which serves as a donor of the carboxymethyl group. We show that microcin C-like compounds carrying terminal cytosines are biologically active and target aspartyl-tRNA synthetase, and that the carboxymethyl group prevents resistance that can occur due to modification of the warhead. The results expand the repertoire of known enzymatic modifications of peptides that can be used to obtain new biological activities while avoiding or limiting bacterial resistance.

  Adenosine-diphosphate (ADP) reduces infarct size and improves porcine heart function after myocardial infarction

DEFF Research Database (Denmark)

Bune, Laurids Touborg; Larsen, Jens Kjærgaard Rolighed; Thaning, Pia

2013-01-01

Acute myocardial infarction continues to be a major cause of morbidity and mortality. Timely reperfusion can substantially improve outcomes and the administration of cardioprotective substances during reperfusion is therefore highly attractive. Adenosine diphosphate (ADP) and uridine-5-triphoshat...... infusion during reperfusion reduces IS by ~20% independently from systemic release of t-PA. ADP-induced reduction in both preload and afterload could account for the beneficial myocardial effect....

Geranylgeranyl diphosphate synthase in fission yeast is a heteromer of farnesyl diphosphate synthase (FPS), Fps1, and an FPS-like protein, Spo9, essential for sporulation.

Science.gov (United States)

Ye, Yanfang; Fujii, Makoto; Hirata, Aiko; Kawamukai, Makoto; Shimoda, Chikashi; Nakamura, Taro

2007-09-01

Both farnesyl diphosphate synthase (FPS) and geranylgeranyl diphosphate synthase (GGPS) are key enzymes in the synthesis of various isoprenoid-containing compounds and proteins. Here, we describe two novel Schizosaccharomyces pombe genes, fps1(+) and spo9(+), whose products are similar to FPS in primary structure, but whose functions differ from one another. Fps1 is essential for vegetative growth, whereas, a spo9 null mutant exhibits temperature-sensitive growth. Expression of fps1(+), but not spo9(+), suppresses the lethality of a Saccharomyces cerevisiae FPS-deficient mutant and also restores ubiquinone synthesis in an Escherichia coli ispA mutant, which lacks FPS activity, indicating that S. pombe Fps1 in fact functions as an FPS. In contrast to a typical FPS gene, no apparent GGPS homologues have been found in the S. pombe genome. Interestingly, although neither fps1(+) nor spo9(+) expression alone in E. coli confers clear GGPS activity, coexpression of both genes induces such activity. Moreover, the GGPS activity is significantly reduced in the spo9 mutant. In addition, the spo9 mutation perturbs the membrane association of a geranylgeranylated protein, but not that of a farnesylated protein. Yeast two-hybrid and coimmunoprecipitation analyses indicate that Fps1 and Spo9 physically interact. Thus, neither Fps1 nor Spo9 alone functions as a GGPS, but the two proteins together form a complex with GGPS activity. Because spo9 was originally identified as a sporulation-deficient mutant, we show here that expansion of the forespore membrane is severely inhibited in spo9Delta cells. Electron microscopy revealed significant accumulation membrane vesicles in spo9Delta cells. We suggest that lack of GGPS activity in a spo9 mutant results in impaired protein prenylation in certain proteins responsible for secretory function, thereby inhibiting forespore membrane formation.

Modification of zirconium diphosphate with salicylic acid and its effect on the uranium (Vi) sorption; Modificacion del difosfato de circonio con acido salicilico y su efecto sobre la sorcion de uranio (VI)

Energy Technology Data Exchange (ETDEWEB)

Almazan T, M. G.; Garcia G, N. [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico); Simoni, E., E-mail: guadalupe.almazan@inin.gob.mx [Universidad Paris Sud, Instituto de Fisica Nuclear, Georges Clemenceau No. 15, Orsay (France)

2014-10-15

The surface of zirconium diphosphate (ZrP{sub 2}O{sub 7}) was modified with salicylic acid and its effect was evaluated on the uranium (Vi) sorption. The modified surface of the material was analyzed with different analytical techniques among which are included the atomic force microscopy, scanning electron microscopy and X-ray photoelectron spectroscopy. This analysis allowed showing that the salicylic acid is being held on the surface of the zirconium diphosphate. The reactivity of modified zirconium diphosphate compared with uranium (Vi) was investigated using the classical method of batch sorption. The analysis of sorption isotherms shows that the salicylic acid has an important effect in the uranium (Vi) sorption. According to the study conducted, the interaction among the uranium (Vi) and the surface of zirconium diphosphate modified with the salicylic acid most likely leads to the complexes formation of binary (U(Vi)/ZrP{sub 2}O{sub 7}) and ternary (U(Vi)/salicylate/ZrP{sub 2}O{sub 7}) surface. (Author)

Role of choline deficiency in the Fatty liver phenotype of mice fed a low protein, very low carbohydrate ketogenic diet.

Directory of Open Access Journals (Sweden)

Rebecca C Schugar

Full Text Available Though widely employed for clinical intervention in obesity, metabolic syndrome, seizure disorders and other neurodegenerative diseases, the mechanisms through which low carbohydrate ketogenic diets exert their ameliorative effects still remain to be elucidated. Rodent models have been used to identify the metabolic and physiologic alterations provoked by ketogenic diets. A commonly used rodent ketogenic diet (Bio-Serv F3666 that is very high in fat (~94% kcal, very low in carbohydrate (~1% kcal, low in protein (~5% kcal, and choline restricted (~300 mg/kg provokes robust ketosis and weight loss in mice, but through unknown mechanisms, also causes significant hepatic steatosis, inflammation, and cellular injury. To understand the independent and synergistic roles of protein restriction and choline deficiency on the pleiotropic effects of rodent ketogenic diets, we studied four custom diets that differ only in protein (5% kcal vs. 10% kcal and choline contents (300 mg/kg vs. 5 g/kg. C57BL/6J mice maintained on the two 5% kcal protein diets induced the most significant ketoses, which was only partially diminished by choline replacement. Choline restriction in the setting of 10% kcal protein also caused moderate ketosis and hepatic fat accumulation, which were again attenuated when choline was replete. Key effects of the 5% kcal protein diet - weight loss, hepatic fat accumulation, and mitochondrial ultrastructural disarray and bioenergetic dysfunction - were mitigated by choline repletion. These studies indicate that synergistic effects of protein restriction and choline deficiency influence integrated metabolism and hepatic pathology in mice when nutritional fat content is very high, and support the consideration of dietary choline content in ketogenic diet studies in rodents to limit hepatic mitochondrial dysfunction and fat accumulation.

A choline-deficient diet exacerbates fatty liver but attenuates insulin resistance and glucose intolerance in mice fed a high-fat diet.

Science.gov (United States)

Raubenheimer, Peter J; Nyirenda, Moffat J; Walker, Brian R

2006-07-01

Liver fat accumulation is proposed to link obesity and insulin resistance. To dissect the role of liver fat in the insulin resistance of diet-induced obesity, we altered liver fat using a choline-deficient diet. C57Bl/6 mice were fed a low-fat (10% of calories) or high-fat (45% of calories) diet for 8 weeks; during the final 4 weeks, diets were either choline deficient or choline supplemented. In choline replete animals, high-fat feeding induced weight gain, elevated liver triglycerides (171%), hyperinsulinemia, and glucose intolerance. Choline deficiency did not affect body or adipose depot weights but amplified liver fat accumulation with high-fat diet (281%, P insulin (from 983 +/- 175 to 433 +/- 36 pmol/l, P phosphatidylcholine synthesis and of enzymes involved in free fatty acid esterification, without affecting those of de novo lipogenesis or fatty acid oxidation. We conclude that liver fat accumulation per se does not cause insulin resistance during high-fat feeding and that choline deficiency may shunt potentially toxic free fatty acids toward innocuous storage triglyceride in the liver.

Synthesis of a tritium labeled photolabile analogue of farnesyl diphosphate: (E,E)-[1-3H]-(2-diazo-3-trifluoropropionyloxy)geranyl diphosphate (DATFP-GDP)

International Nuclear Information System (INIS)

Liu, J.; Benedict, C.R.

1996-01-01

Tritiated (E,E)-(2-diazo-3-trifluoropropionyloxy)geranyl disphosphate (DATFP-GDP) has been used as a photolabile analogue of (E,E)-farnesyl diphosphate (E,E-FDP) for an aid in isolating enzymes utilizing E,E-FDP as a substrate. We now report an alternative method of synthesizing this probe in which the tritium label is introduced in the step just before the introduction of the diphospate group. Thus, DATFP-geranial is oxidized to DATFP-geranial with activated manganese dioxide. The tritium label is introduced by reduction of the aldehyde with NaBT 4 . The DATFP-group successfully withstands both of these steps. The overall yield for these two steps is 69%. Diphosphorylation of the resulting alcohol afforded DATFP-[1- 3 H]-GDP in 8% yield with a specific activity of 48.6 μCi/μmol and radiochemical purity of 94%. (Author)

7-methylguanosine diphosphate (m(7)GDP) is not hydrolyzed but strongly bound by decapping scavenger (DcpS) enzymes and potently inhibits their activity.

Science.gov (United States)

Wypijewska, Anna; Bojarska, Elzbieta; Lukaszewicz, Maciej; Stepinski, Janusz; Jemielity, Jacek; Davis, Richard E; Darzynkiewicz, Edward

2012-10-09

Decapping scavenger (DcpS) enzymes catalyze the cleavage of a residual cap structure following 3' → 5' mRNA decay. Some previous studies suggested that both m(7)GpppG and m(7)GDP were substrates for DcpS hydrolysis. Herein, we show that mononucleoside diphosphates, m(7)GDP (7-methylguanosine diphosphate) and m(3)(2,2,7)GDP (2,2,7-trimethylguanosine diphosphate), resulting from mRNA decapping by the Dcp1/2 complex in the 5' → 3' mRNA decay, are not degraded by recombinant DcpS proteins (human, nematode, and yeast). Furthermore, whereas mononucleoside diphosphates (m(7)GDP and m(3)(2,2,7)GDP) are not hydrolyzed by DcpS, mononucleoside triphosphates (m(7)GTP and m(3)(2,2,7)GTP) are, demonstrating the importance of a triphosphate chain for DcpS hydrolytic activity. m(7)GTP and m(3)(2,2,7)GTP are cleaved at a slower rate than their corresponding dinucleotides (m(7)GpppG and m(3)(2,2,7)GpppG, respectively), indicating an involvement of the second nucleoside for efficient DcpS-mediated digestion. Although DcpS enzymes cannot hydrolyze m(7)GDP, they have a high binding affinity for m(7)GDP and m(7)GDP potently inhibits DcpS hydrolysis of m(7)GpppG, suggesting that m(7)GDP may function as an efficient DcpS inhibitor. Our data have important implications for the regulatory role of m(7)GDP in mRNA metabolic pathways due to its possible interactions with different cap-binding proteins, such as DcpS or eIF4E.

PET imaging of hepatocellular carcinoma with {sup 18}F-fluoroethylcholine and {sup 11}C-choline

Energy Technology Data Exchange (ETDEWEB)

Kolthammer, Jeffrey A.; Tenley, Nathan [Case Western Reserve University, Department of Biomedical Engineering, Cleveland, OH (United States); Corn, David J.; Wu, Chunying; Tian, Haibin; Wang, Yanming [University Hospitals Case Medical Center, Nuclear Medicine Division, Department of Radiology, Cleveland, OH (United States); Lee, Zhenghong [Case Western Reserve University, Department of Biomedical Engineering, Cleveland, OH (United States); University Hospitals Case Medical Center, Nuclear Medicine Division, Department of Radiology, Cleveland, OH (United States)

2011-07-15

Choline-based radiotracers have been studied for PET imaging of hepatocellular carcinoma (HCC). Using an {sup 18}F-labeled choline analog, instead of the {sup 11}C-labeled native choline, would facilitate its widespread use in the clinic. In this study, PET with {sup 18}F-fluoroethylcholine (FEC) and {sup 11}C-choline (CHOL) were compared using an animal model of HCC. The effects of fasting on the performance of choline-based tracers were also investigated. A woodchuck model of HCC was used to compare the two tracers, which were administered and imaged in sequence during the same imaging session. Dynamic PET images were generated spanning 50 min starting from tracer injection. Time-activity curves and tracer contrast were calculated in liver regions with tracer accumulation, and the contrast at a late time-point with the two tracers, and between fasted and nonfasted states, were compared. Foci of HCC with increased uptake ranged in size from 1.0 to 1.6 cm, with mean tumor-to-background contrast of 1.3 with FEC and 1.5 with CHOL at 50 min after injection. The tracers show similar patterns of uptake immediately following administration, and both activities plateaued at 10 min after injection. No significant differences in uptake dynamics or final contrast were observed between the fasted and nonfasted states. PET imaging of HCC is possible with both CHOL and FEC. Fasting was not found to affect accumulation of either tracer. These results encourage further investigation into the clinical utility of FEC for HCC imaging. (orig.)

Production, purification, crystallization and preliminary X-ray diffraction studies of the nucleoside diphosphate kinase b from Leishmania major

International Nuclear Information System (INIS)

Tonoli, Celisa Caldana Costa; Vieira, Plinio Salmazo; Ward, Richard John; Arni, Raghuvir Krishnaswamy; Oliveira, Arthur Henrique Cavalcante de; Murakami, Mario Tyago

2009-01-01

Overexpression, purification, crystallization and preliminary X-ray diffraction analysis of the nucleoside diphosphate kinase b from Leishmania major are reported. The crystals belonged to the trigonal space group P3 2 21 and diffracted to 2.18 Å resolution. Nucleoside diphosphate kinases (NDKs; EC 2.7.4.6) play an essential role in the synthesis of nucleotides from intermediates in the salvage pathway in all parasitic trypanosomatids and their structural studies will be instrumental in shedding light on the biochemical machinery involved in the parasite life cycle and host–parasite interactions. In this work, NDKb from Leishmania major was overexpressed in Escherichia coli, purified to homogeneity and crystallized using the sitting-drop vapour-diffusion method. The NDK crystal diffracted to 2.2 Å resolution and belonged to the trigonal crystal system, with unit-cell parameters a = 114.2, c = 93.9 Å. Translation-function calculations yielded an unambiguous solution in the enantiomorphic space group P3 2 21

Maternal Choline Supplementation: A Potential Prenatal Treatment for Down Syndrome and Alzheimer's Disease.

Science.gov (United States)

Strupp, Barbara J; Powers, Brian E; Velazquez, Ramon; Ash, Jessica A; Kelley, Christy M; Alldred, Melissa J; Strawderman, Myla; Caudill, Marie A; Mufson, Elliott J; Ginsberg, Stephen D

2016-01-01

Although Down syndrome (DS) can be diagnosed prenatally, currently there are no effective treatments to lessen the intellectual disability (ID) which is a hallmark of this disorder. Furthermore, starting as early as the third decade of life, DS individuals exhibit the neuropathological hallmarks of Alzheimer's disease (AD) with subsequent dementia, adding substantial emotional and financial burden to their families and society at large. A potential therapeutic strategy emerging from the study of trisomic mouse models of DS is to supplement the maternal diet with additional choline during pregnancy and lactation. Studies demonstrate that maternal choline supplementation (MCS) markedly improves spatial cognition and attentional function, as well as normalizes adult hippocampal neurogenesis and offers protection to basal forebrain cholinergic neurons (BFCNs) in the Ts65Dn mouse model of DS. These effects on neurogenesis and BFCNs correlate significantly with spatial cognition, suggesting functional relationships. In this review, we highlight some of these provocative findings, which suggest that supplementing the maternal diet with additional choline may serve as an effective and safe prenatal strategy for improving cognitive, affective, and neural functioning in DS. In light of growing evidence that all pregnancies would benefit from increased maternal choline intake, this type of recommendation could be given to all pregnant women, thereby providing a very early intervention for individuals with DS, and include babies born to mothers unaware that they are carrying a fetus with DS.

Structural and thermodynamic basis of the inhibition of Leishmania major farnesyl diphosphate synthase by nitrogen-containing bisphosphonates

Energy Technology Data Exchange (ETDEWEB)

Aripirala, Srinivas [Johns Hopkins University, 725 North Wolfe Street WBSB 605, Baltimore, MD 21210 (United States); Gonzalez-Pacanowska, Dolores [López-Neyra Institute of Parasitology and Biomedicine, 18001 Granada (Spain); Oldfield, Eric [University of Illinois at Urbana-Champaign, Urbana, IL 61801 (United States); Kaiser, Marcel [University of Basel, Petersplatz 1, CH-4003 Basel (Switzerland); Amzel, L. Mario, E-mail: mamzel@jhmi.edu [Johns Hopkins University School of Medicine, 725 N. Wolfe Street WBSB 604, Baltimore, MD 21205 (United States); Gabelli, Sandra B., E-mail: mamzel@jhmi.edu [Johns Hopkins University School of Medicine, 725 N. Wolfe Street WBSB 604, Baltimore, MD 21205 (United States); Johns Hopkins University School of Medicine, Baltimore, MD 21205 (United States); Johns Hopkins University, 725 North Wolfe Street WBSB 605, Baltimore, MD 21210 (United States)

2014-03-01

Structural insights into L. major farnesyl diphosphate synthase, a key enzyme in the mevalonate pathway, are described. Farnesyl diphosphate synthase (FPPS) is an essential enzyme involved in the biosynthesis of sterols (cholesterol in humans and ergosterol in yeasts, fungi and trypanosomatid parasites) as well as in protein prenylation. It is inhibited by bisphosphonates, a class of drugs used in humans to treat diverse bone-related diseases. The development of bisphosphonates as antiparasitic compounds targeting ergosterol biosynthesis has become an important route for therapeutic intervention. Here, the X-ray crystallographic structures of complexes of FPPS from Leishmania major (the causative agent of cutaneous leishmaniasis) with three bisphosphonates determined at resolutions of 1.8, 1.9 and 2.3 Å are reported. Two of the inhibitors, 1-(2-hydroxy-2,2-diphosphonoethyl)-3-phenylpyridinium (300B) and 3-butyl-1-(2,2-diphosphonoethyl)pyridinium (476A), co-crystallize with the homoallylic substrate isopentenyl diphosphate (IPP) and three Ca{sup 2+} ions. A third inhibitor, 3-fluoro-1-(2-hydroxy-2,2-diphosphonoethyl)pyridinium (46I), was found to bind two Mg{sup 2+} ions but not IPP. Calorimetric studies showed that binding of the inhibitors is entropically driven. Comparison of the structures of L. major FPPS (LmFPPS) and human FPPS provides new information for the design of bisphosphonates that will be more specific for inhibition of LmFPPS. The asymmetric structure of the LmFPPS–46I homodimer indicates that binding of the allylic substrate to both monomers of the dimer results in an asymmetric dimer with one open and one closed homoallylic site. It is proposed that IPP first binds to the open site, which then closes, opening the site on the other monomer, which closes after binding the second IPP, leading to the symmetric fully occupied FPPS dimer observed in other structures.

Involvement of an ent-copalyl diphosphate synthase in tissue-specific accumulation of specialized diterpenes in Andrographis paniculata.

Science.gov (United States)

Misra, Rajesh Chandra; Garg, Anchal; Roy, Sudeep; Chanotiya, Chandan Singh; Vasudev, Prema G; Ghosh, Sumit

2015-11-01

Ent-labdane-related diterpene (ent-LRD) specialized (i.e. secondary) metabolites of the medicinal plant kalmegh (Andrographis paniculata) have long been known for several pharmacological activities. However, our understanding of the ent-LRD biosynthetic pathway has remained largely incomplete. Since ent-LRDs accumulate in leaves, we carried out a comparative transcriptional analysis using leaf and root tissues, and identified 389 differentially expressed transcripts, including 223 transcripts that were preferentially expressed in leaf tissue. Analysis of the transcripts revealed various specialized metabolic pathways, including transcripts of the ent-LRD biosynthetic pathway. Two class II diterpene synthases (ApCPS1 and ApCPS2) along with one (ApCPS1') and two (ApCPS2' and ApCPS2″) transcriptional variants that were the outcomes of alternative splicing of the precursor mRNA and alternative transcriptional termination, respectively, were identified. ApCPS1 and ApCPS2 encode for 832- and 817-amino acids proteins, respectively, and are phylogenetically related to the dicotyledons ent-copalyl diphosphate synthases (ent-CPSs). The spatio-temporal patterns of ent-LRD metabolites accumulation and gene expression suggested a likely role for ApCPS1 in general (i.e. primary) metabolism, perhaps by providing precursor for the biosynthesis of phytohormone gibberellin (GA). However, ApCPS2 is potentially involved in tissue-specific accumulation of ent-LRD specialized metabolites. Bacterially expressed recombinant ApCPS2 catalyzed the conversion of (E,E,E)-geranylgeranyl diphosphate (GGPP), the general precursor of diterpenes to ent-copalyl diphosphate (ent-CPP), the precursor of ent-LRDs. Taken together, these results advance our understanding of the tissue-specific accumulation of specialized ent-LRDs of medicinal importance. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Choline and/or folic acid deficiency is associated with genomic damage and cell death in human lymphocytes in vitro.

Science.gov (United States)

Lu, Lin; Ni, Juan; Zhou, Tao; Xu, Weijiang; Fenech, Michael; Wang, Xu

2012-04-01

Choline and folate are interrelated methyl donors. Previous studies showed that folate prevents genomic damage in human lymphocytes in vitro; however, the association between choline and human genomic stability is uncertain. To explore the genotoxicity, cytotoxicity, and cytostatic effects and possible interactions of choline and/or folate deficiency on the human genome, lymphocytes from 6 volunteers were cultured in 18 combinations of choline (CC) and folic acid (FA) media for 9 days. The genotoxicity was evaluated by micronuclei, nucleoplasmic bridges, and nuclear buds in the binucleated cell; the cytotoxicity indices included apoptosis and necrosis, and the cytostatic effects were indicated by nuclear division index (NDI). Across all choline concentrations, the frequencies of all biomarkers except NDI were diminished when FA concentration was more than or equal to 120 nmol/L. The frequencies of micronuclei, buds, and necrosis were significantly higher at lower levels of CC (0-6 μmol/L) compared with higher concentrations of CC (12-21.5 μmol/L) while maintaining the same FA concentration. We concluded that both choline and folate significantly impact genomic stability and cell death, although effects of folate were 2.5- to 6.2-fold greater, depending on the biomarker and dose. A combination of 12 μmol/L CC and 120 nmol/L FA appears to be optimal for genomic integrity in vitro.

Cytidine deaminases from B. subtilis and E. coli: compensating effects of changing zinc coordination and quaternary structure.

Science.gov (United States)

Carlow, D C; Carter, C W; Mejlhede, N; Neuhard, J; Wolfenden, R

1999-09-21

Cytidine deaminase from E. coli is a dimer of identical subunits (M(r) = 31 540), each containing a single zinc atom. Cytidine deaminase from B. subtilis is a tetramer of identical subunits (M(r) = 14 800). After purification from an overexpressing strain, the enzyme from B. subtilis is found to contain a single atom of zinc per enzyme subunit by flame atomic absorption spectroscopy. Fluorescence titration indicates that each of the four subunits contains a binding site for the transition state analogue inhibitor 5-fluoro-3,4-dihydrouridine. A region of amino acid sequence homology, containing residues that are involved in zinc coordination in the enzyme from E. coli, strongly suggests that in the enzyme from B. subtilis, zinc is coordinated by the thiolate side chains of three cysteine residues (Cys-53, Cys-86, and Cys-89) [Song, B. H., and Neuhard, J. (1989) Mol. Gen. Genet. 216, 462-468]. This pattern of zinc coordination appears to be novel for a hydrolytic enzyme, and might be expected to reduce the reactivity of the active site substantially compared with that of the enzyme from E. coli (His-102, Cys-129, and Cys-132). Instead, the B. subtilis and E. coli enzymes are found to be similar in their activities, and also in their relative binding affinities for a series of structurally related inhibitors with binding affinities that span a range of 6 orders of magnitude. In addition, the apparent pK(a) value of the active site is shifted upward by less than 1 unit. Sequence alignments, together with model building, suggest one possible mechanism of compensation.

The detection rate of [11C]Choline-PET/CT depends on the serum PSA-value in patients with biochemical recurrence of prostate cancer

International Nuclear Information System (INIS)

Krause, B.J.; Souvatzoglou, M.; Tuncel, M.; Herrmann, K.; Buck, A.K.; Praus, C.; Schwaiger, M.; Schuster, T.; Geinitz, H.; Treiber, U.

2008-01-01

An increase of the serum PSA-level is a sensitive in vitro marker for recurrent prostate cancer. However, it remains difficult to differentiate between local, regional or distant recurrent disease. The aim of this study was to assess the relationship between the detection rate of [ 11 C]Choline-PET/CT and the serum PSA-level in patients with a biochemical recurrence of prostate cancer with the view towards localisation of recurrent disease. Sixty-three patients (mean age, 68.8 ± 6.9; range, 45-83 years) with biochemical recurrence after primary therapy for prostate cancer were included in the analysis. Mean PSA-levels were 5.9 ± 9.7 ng/ml (range, 0.2-39 ng/ml; median, 2.15). Of the 63 patients, 17 were under anti-androgen therapy at the time of [ 11 C]Choline PET/CT. Patients underwent a [ 11 C]Choline-PET/CT study after injection of 656 ± 119 MBq [ 11 C]Choline on a Sensation 16 Biograph PET/CT scanner. Of the 63 patients, 35 (56%) showed a pathological [ 11 C]Choline uptake. The detection rate of [ 11 C]Choline-PET/CT showed a relationship with the serum PSA-level: The detection rate was 36% for a PSA-value 11 C]Choline-PET/CT (p = 0.374). As an important result our study shows that even for PSA-values 11 C]Choline-PET/CT is 36%. Furthermore, the detection rate of [ 11 C]Choline-PET/CT shows a positive relationship with serum PSA-levels in patients with biochemical recurrence of prostate cancer after primary therapy. Therefore, in these patients, [ 11 C]Choline PET/CT allows not only to diagnose but also to localise recurrent disease with implications on disease management (localised vs systemic therapy). (orig.)

Choline Phospholipid Metabolites of Human Vascular Endothelial Cells Altered by Cyclooxygenase Inhibition, Growth Factor Depletion, and Paracrine Factors Secreted by Cancer Cells

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Noriko Mori

2003-04-01

Full Text Available Magnetic resonance studies have previously shown that solid tumors and cancer cells in culture typically exhibit high phosphocholine and total choline. Treatment of cancer cells with the anti-inflammatory agent, indomethacin (INDO, reverted the phenotype of choline phospholipid metabolites in cancer cells towards a less malignant phenotype. Since endothelial cells form a key component of tumor vasculature, in this study, we used MR spectroscopy to characterize the phenotype of choline phospholipid metabolites in human umbilical vein endothelial cells (HUVECs. We determined the effect of growth factors, the anti-inflammatory agent INDO, and conditioned media obtained from a malignant cell line, on choline phospholipid metabolites. Growth factor depletion or treatment with INDO induced similar changes in the choline phospholipid metabolites of HUVECs. Treatment with conditioned medium obtained from MDA-MB-231 cancer cells induced changes similar to the presence of growth factor supplements. These results suggest that cancer cells secrete growth factors and/or other molecules that influence the choline phospholipid metabolism of HUVECs. The ability of INDO to alter choline phospholipid metabolism in the presence of growth factor supplements suggests that the inflammatory response pathways of HUVECs may play a role in cancer cell-HUVEC interaction and in the response of HUVECs to growth factors.

Studies on the riboflavin, niacin, pantothenic acid and choline requirements of young bobwhite quail

Science.gov (United States)

Serafin, J.A.

1974-01-01

Four experiments were conducted to examine the riboflavin, niacin, pantothenic acid and choline requirements of young Bobwhite quail. Quail fed purified diets deficient in either riboflavin, niacin, pantothenic acid or choline grew poorly and high mortality occurred by 5 weeks of age. Under the conditions of these experiments, it was found that: (1) young quail require approximately 3.8 mg. riboflavin/kg. diet for satisfactory growth and survival; (2) no more than 31 mg. niacin/kg. diet are required for normal growth and survival of young quail; (3) the requirement for pantothenic acid is higher than has previously been reported, quail in these studies requiring 12.6 mg. pantothenic acid/kg. feed for growth and survival; and (4) the requirement for choline for reducing mortality is approximately 1000 mg./kg., while the amount necessary for normal growth of young quail is no greater than 1500 mg./kg. when the diet contains ample amounts of methionine. Quail fed a niacin-deficient diet developed stiff, shortened feathers and an erythema about the head; those receiving a riboflavin-deficient ration developed enlarged hocks and bowed legs, as did quail fed diets low or devoid of choline. Aside from slow growth, poor feathering was the only other indication that a deficient diet was being fed when quail were placed on a basal ration without pantothenic acid for five weeks.

Variability of Gross Tumor Volume in Nasopharyngeal Carcinoma Using 11C-Choline and 18F-FDG PET/CT.

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Jun Jiang

Full Text Available This study was conducted to evaluate the variability of gross tumor volume (GTV using 11C-Choline and 18F-FDG PET/CT images for nasopharyngeal carcinomas boundary definition. Assessment consisted of inter-observer and inter-modality variation analysis. Four radiation oncologists were invited to manually contour GTV by using PET/CT fusion obtained from a cohort of 12 patients with nasopharyngeal carcinoma (NPC and who underwent both 11C-Choline and 18F-FDG scans. Student's paired-sample t-test was performed for analyzing inter-observer and inter-modality variability. Semi-automatic segmentation methods, including thresholding and region growing, were also validated against the manual contouring of the two types of PET images. We observed no significant variation in the results obtained by different oncologists in terms of the same type of PET/CT volumes. Choline fusion volumes were significantly larger than the FDG volumes (p < 0.0001, mean ± SD = 18.21 ± 8.19. While significantly consistent results were obtained between the oncologists and the standard references in Choline volumes compared with those in FDG volumes (p = 0.0025. Simple semi-automatic delineation methods indicated that 11C-Choline PET images could provide better results than FDG volumes (p = 0.076, CI = [-0.29, 0.025]. 11C-Choline PET/CT may be more advantageous in GTV delineation for the radiotherapy of NPC than 18F-FDG. Phantom simulations and clinical trials should be conducted to prove the possible improvement of the treatment outcome.

Ocular lesions and experimental choline deficiency Lesiones oculares y deficiencia experimental de colina

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Georgina P. Ossani

2006-10-01

Full Text Available Previous studies have shown ocular haemorrhages in choline-deficient rats. The aim of this paper is to study further the relationship between ocular and renal lesions and biochemical alterations in rats fed a choline-deficient diet. Fifty one weanling male Wistar rats, were divided into two groups. Thirty one of them were fed a choline-deficient diet and the rest was fed a choline-supplemented diet ad libitum. Animals from both groups were killed between the fifth and the eighth day. Urea, creatinine and homocysteine concentrations in blood were determined. Eyes were used for light microscopy study; high resolution light microscopy and the study of the retina as "rétine a plat". Kidneys were studied by light microscopy. Choline-supplemented rats did not show ocular or renal lesion. Choline-deficient rats that showed renal lesions, tubular or cortical necrosis, did not always have ocular changes. There were no ocular changes in the only choline-deficient rat without renal lesion. The ocular changes consisted mainly in haemorrhage in both cameras and ciliary and vitreous bodies. Correlations between ocular and renal lesion (r=0.72, pEstudios previos han demostrado hemorragia ocular en ratas deficientes en colina. El objetivo de este trabajo es profundizar en la relación entre las alteraciones oculares, renales y bioquímicas en ratas deficientes en colina. Cincuenta y una ratas Wistar macho recién destetadas fueron divididas en dos grupos: treinta y una fueron alimentadas con una dieta colino deficiente y el resto con colina suplementada ad-libitum. Los animales de ambos grupos fueron sacrificados entre el quinto y el octavo día. Se midió la concentración de urea, creatinina y homocisteína en sangre. Los ojos fueron estudiados por microscopía de luz, microscopía óptica de alta resolución y para el estudio de la retina como retina plana. Los riñones fueron estudiados por microscopía de luz. Las ratas suplementadas con colina no

Hepatic conversion of bilirubin monoglucuronide to diglucuronide in uridine diphosphate-glucuronyl transferase-deficient man and rat by bilirubin glucuronoside glucuronosyltransferase

NARCIS (Netherlands)

Chowdhury, J. R.; Jansen, P. L.; Fischberg, E. B.; Daniller, A.; Arias, I. M.

1978-01-01

The microsomal enzyme uridine diphosphate (UDP) glucuronate glucuronyltransferase (E.C. 2.4.1.17) catalyzes formation of bilirubin mono-glucuronide from bilirubin and UDPglucuronic acid. Bilirubin glucuronoside glucuronosyltransferase (E.C. 2.4.1.95), an enzyme concentrated in plasma

Choline chloride-based deep eutectic solvents as additives for optimizing chromatographic behavior of caffeic acid

International Nuclear Information System (INIS)

Li, Guizhen; Zhu, Tao; Lei, Yingjie

2015-01-01

A series of deep eutectic solvents (DESs) were prepared using glycerol and choline chloride (ChCl), and Fourier transform infrared spectrometer (FT-IR) was used to analyze the spectra of glycerol, choline chloride and DESs based on glycerol and choline chloride. Then DESs were used as the additives of mobile phase to optimize chromatographic behavior of caffeic acid in high performance liquid chromatography (HPLC). A 17-run Box-Behnken design (BBD) was employed to evaluate effect of DESs as additives by analyzing the maximum theoretical plate number. Three factors, reaction temperature (60 .deg. C, 80 .deg. C, 100 .deg. C), molar ratio of glycerol and choline chloride (2 : 1, 3 : 1, 4 : 1, n/n), and volume percent of additives (0.05%, 0.10%, 0.15%, v/v), were investigated in BBD. The optimum experiment condition was that of reaction temperature (80 .deg. C), molar ratio of glycerol and ChCl (3 : 1, n/n), and volume percent of additive (0.10%, v/v). The mean chromatographic theoretical plate number of the caffeic acid this condition was 1567.5, and DESs as additives shorten the retention time and modify the chromatogram shape, proving DESs as additives for effective theoretical plate number and column efficiency in HPLC.

Choline chloride-based deep eutectic solvents as additives for optimizing chromatographic behavior of caffeic acid

Energy Technology Data Exchange (ETDEWEB)

Li, Guizhen; Zhu, Tao; Lei, Yingjie [Tianjin University of Technology, Tianjin (China)

2015-10-15

A series of deep eutectic solvents (DESs) were prepared using glycerol and choline chloride (ChCl), and Fourier transform infrared spectrometer (FT-IR) was used to analyze the spectra of glycerol, choline chloride and DESs based on glycerol and choline chloride. Then DESs were used as the additives of mobile phase to optimize chromatographic behavior of caffeic acid in high performance liquid chromatography (HPLC). A 17-run Box-Behnken design (BBD) was employed to evaluate effect of DESs as additives by analyzing the maximum theoretical plate number. Three factors, reaction temperature (60 .deg. C, 80 .deg. C, 100 .deg. C), molar ratio of glycerol and choline chloride (2 : 1, 3 : 1, 4 : 1, n/n), and volume percent of additives (0.05%, 0.10%, 0.15%, v/v), were investigated in BBD. The optimum experiment condition was that of reaction temperature (80 .deg. C), molar ratio of glycerol and ChCl (3 : 1, n/n), and volume percent of additive (0.10%, v/v). The mean chromatographic theoretical plate number of the caffeic acid this condition was 1567.5, and DESs as additives shorten the retention time and modify the chromatogram shape, proving DESs as additives for effective theoretical plate number and column efficiency in HPLC.

Structure of the ent -Copalyl Diphosphate Synthase PtmT2 from Streptomyces platensis CB00739, a Bacterial Type II Diterpene Synthase

Energy Technology Data Exchange (ETDEWEB)

Rudolf, Jeffrey D.; Dong, Liao-Bin; Cao, Hongnan; Hatzos-Skintges, Catherine; Osipiuk, Jerzy; Endres, Michael; Chang, Chin-Yuan; Ma, Ming; Babnigg, Gyorgy; Joachimiak, Andrzej; Phillips, George N.; Shen, Ben

2016-08-31

Terpenoids are the largest and most structurally diverse family of natural products found in nature, yet their presence in bacteria is underappreciated. The carbon skeletons of terpenoids are generated through carbocation-dependent cyclization cascades catalyzed by terpene synthases (TSs). Type I and type II TSs initiate cyclization via diphosphate ionization and protonation, respectively, and protein structures of both types are known. Most plant diterpene synthases (DTSs) possess three alpha-helical domains (alpha beta gamma), which are thought to have arisen from the fusion of discrete, ancestral bacterial type I TSs (alpha) and type II TSs (beta gamma). Type II DTSs of bacterial origin, of which there are no structurally characterized members, are a missing piece in the structural evolution of TSs. Here, we report the first crystal structure of a type II DTS from bacteria. PtnaT2 from Streptomyces platensis CB00739 was verified as an ent-copalyl diphosphate synthase involved in the biosynthesis of platensimycin and platencin. The crystal structure of PtmT2 was solved at a resolution of 1.80 angstrom, and docking studies suggest the catalytically active conformation of geranylgeranyl diphosphate (GGPP). Site-directed mutagenesis confirmed residues involved in binding the diphosphate moiety of GGPP and identified DxxxxE as a potential Mg2+-binding motif for type II DTSs of bacterial origin. Finally, both the shape and physicochemical properties of the active sites are responsible for determining specific catalytic outcomes of TSs. The structure of PtmT2 fundamentally advances the knowledge of bacterial TSs, their mechanisms, and their role in the evolution of TSs.

Overexpression of an isopentenyl diphosphate isomerase gene to enhance trans-polyisoprene production in Eucommia ulmoides Oliver

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Chen Ren

2012-10-01

Full Text Available Abstract Background Natural rubber produced by plants, known as polyisoprene, is the most widely used isoprenoid polymer. Plant polyisoprenes can be classified into two types; cis-polyisoprene and trans-polyisoprene, depending on the type of polymerization of the isoprene unit. More than 2000 species of higher plants produce latex consisting of cis-polyisoprene. Hevea brasiliensis (rubber tree produces cis-polyisoprene, and is the key source of commercial rubber. In contrast, relatively few plant species produce trans-polyisoprene. Currently, trans-polyisoprene is mainly produced synthetically, and no plant species is used for its commercial production. Results To develop a plant-based system suitable for large-scale production of trans-polyisoprene, we selected a trans-polyisoprene-producing plant, Eucommia ulmoides Oliver, as the target for genetic transformation. A full-length cDNA (designated as EuIPI, Accession No. AB041629 encoding isopentenyl diphosphate isomerase (IPI was isolated from E. ulmoides. EuIPI consisted of 1028 bp with a 675-bp open reading frame encoding a protein with 224 amino acid residues. EuIPI shared high identity with other plant IPIs, and the recombinant protein expressed in Escherichia coli showed IPI enzymatic activity in vitro. EuIPI was introduced into E. ulmoides via Agrobacterium-mediated transformation. Transgenic lines of E. ulmoides overexpressing EuIPI showed increased EuIPI expression (up to 19-fold that of the wild-type and a 3- to 4-fold increase in the total content of trans-polyisoprenes, compared with the wild-type (non-transgenic root line control. Conclusions Increasing the expression level of EuIPI by overexpression increased accumulation of trans-polyisoprenes in transgenic E. ulmoides. IPI catalyzes the conversion of isopentenyl diphosphate to its highly electrophilic isomer, dimethylallyl diphosphate, which is the first step in the biosynthesis of all isoprenoids, including polyisoprene. Our

Choline acetyltransferase expression during periods of behavioral activity and across natural sleep-wake states in the basal forebrain.

Science.gov (United States)

Greco, M A; McCarley, R W; Shiromani, P J

1999-01-01

The present study examined whether the expression of the messenger RNA encoding the protein responsible for acetylcholine synthesis is associated with sleep-wakefulness. Choline acetyltransferase messenger RNA levels were analysed using a semi-quantitative assay in which reverse transcription was coupled to complementary DNA amplification using the polymerase chain reaction. To examine the relationship between steady-state messenger RNA and behavioral activity, rats were killed during the day (4.00 p.m.) or night (4.00 a.m.), and tissue from the vertical and horizontal limbs of the diagonal bands of Broca was analysed. Choline acetyltransferase messenger RNA levels were higher during the day than during the night. The second study examined more closely the association between choline acetyltransferase messenger RNA levels and individual bouts of wakefulness, slow-wave sleep or rapid eye movement sleep. Choline acetyltransferase messenger RNA levels were low during wakefulness, intermediate in slow-wave sleep and high during rapid eye movement sleep. In contrast, protein activity, measured at a projection site of cholinergic neurons of the basal forebrain, was higher during wakefulness than during sleep. These findings suggest that choline acetyltransferase protein and messenger RNA levels exhibit an inverse relationship during sleep and wakefulness. The increased messenger RNA expression during sleep is consistent with a restorative function of sleep.

Choline Catabolism in Burkholderia thailandensis Is Regulated by Multiple Glutamine Amidotransferase 1-Containing AraC Family Transcriptional Regulators.

Science.gov (United States)

Nock, Adam M; Wargo, Matthew J

2016-09-15

Burkholderia thailandensis is a soil-dwelling bacterium that shares many metabolic pathways with the ecologically similar, but evolutionarily distant, Pseudomonas aeruginosa Among the diverse nutrients it can utilize is choline, metabolizable to the osmoprotectant glycine betaine and subsequently catabolized as a source of carbon and nitrogen, similar to P. aeruginosa Orthologs of genes in the choline catabolic pathway in these two bacteria showed distinct differences in gene arrangement as well as an additional orthologous transcriptional regulator in B. thailandensis In this study, we showed that multiple glutamine amidotransferase 1 (GATase 1)-containing AraC family transcription regulators (GATRs) are involved in regulation of the B. thailandensis choline catabolic pathway (gbdR1, gbdR2, and souR). Using genetic analyses and sequencing the transcriptome in the presence and absence of choline, we identified the likely regulons of gbdR1 (BTH_II1869) and gbdR2 (BTH_II0968). We also identified a functional ortholog for P. aeruginosa souR, a GATR that regulates the metabolism of sarcosine to glycine. GbdR1 is absolutely required for expression of the choline catabolic locus, similar to P. aeruginosa GbdR, while GbdR2 is important to increase expression of the catabolic locus. Additionally, the B. thailandensis SouR ortholog (BTH_II0994) is required for catabolism of choline and its metabolites as carbon sources, whereas in P. aeruginosa, SouR function can by bypassed by GbdR. The strategy employed by B. thailandensis represents a distinct regulatory solution to control choline catabolism and thus provides both an evolutionary counterpoint and an experimental system to analyze the acquisition and regulation of this pathway during environmental growth and infection. Many proteobacteria that occupy similar environmental niches have horizontally acquired orthologous genes for metabolism of compounds useful in their shared environment. The arrangement and differential

Effect of herbal choline and rumen-protected methionine on lamb ...

African Journals Online (AJOL)

Elizabeth A Mendoza B MD

2018-01-30

Jan 30, 2018 ... oral doses of rumen-protected methionine (RPM) (0 and 1.5 g/day) and ... and stimulating glucose and cholesterol synthesis. .... The in vitro gas production indicates that half of herbal choline is fermented at 18 hours (Table 2),.

Activation-induced cytidine deaminase deficiency causes organ-specific autoimmune disease.

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Koji Hase

Full Text Available Activation-induced cytidine deaminase (AID expressed by germinal center B cells is a central regulator of somatic hypermutation (SHM and class switch recombination (CSR. Humans with AID mutations develop not only the autosomal recessive form of hyper-IgM syndrome (HIGM2 associated with B cell hyperplasia, but also autoimmune disorders by unknown mechanisms. We report here that AID-/- mice spontaneously develop tertiary lymphoid organs (TLOs in non-lymphoid tissues including the stomach at around 6 months of age. At a later stage, AID-/- mice develop a severe gastritis characterized by loss of gastric glands and epithelial hyperplasia. The disease development was not attenuated even under germ-free (GF conditions. Gastric autoantigen -specific serum IgM was elevated in AID-/- mice, and the serum levels correlated with the gastritis pathological score. Adoptive transfer experiments suggest that autoimmune CD4+ T cells mediate gastritis development as terminal effector cells. These results suggest that abnormal B-cell expansion due to AID deficiency can drive B-cell autoimmunity, and in turn promote TLO formation, which ultimately leads to the propagation of organ-specific autoimmune effector CD4+ T cells. Thus, AID plays an important role in the containment of autoimmune diseases by negative regulation of autoreactive B cells.

Novel class III phosphoribosyl diphosphate synthase: structure and properties of the tetrameric, phosphate-activated, non-allosterically inhibited enzyme from Methanocaldococcus jannaschii

DEFF Research Database (Denmark)

Kadziola, Anders; Jepsen, Clemens H; Johansson, Eva

2005-01-01

The prs gene encoding phosphoribosyl diphosphate (PRPP) synthase of the hyperthermophilic autotrophic methanogenic archaeon Methanocaldococcus jannaschii has been cloned and expressed in Escherichia coli. Subsequently, M.jannaschii PRPP synthase has been purified, characterised, crystallised, and...

Oscillatory bands, neuronal synchrony and hippocampal function: implications of the effects of prenatal choline supplementation for sleep-dependent memory consolidation.

Science.gov (United States)

Cheng, Ruey-Kuang; Williams, Christina L; Meck, Warren H

2008-10-27

Choline supplementation of the maternal diet has long-term facilitative effects on spatial and temporal memory processes in the offspring. To further delineate the impact of early nutritional status on brain and behavior, we examined effects of prenatal-choline availability on hippocampal oscillatory frequency bands in 12 month-old male and female rats. Adult offspring of time-pregnant dams that were given a deficient level of choline (DEF=0.0 g/kg), sufficient choline (CON=1.1 g/kg) or supplemental choline (SUP=3.5 g/kg) in their chow during embryonic days (ED) 12-17 were implanted with an electroencephalograph (EEG) electrode in the hippocampal dentate gyrus in combination with an electromyograph (EMG) electrode patch implanted in the nuchal muscle. Five consecutive 8-h recording sessions revealed differential patterns of EEG activity as a function of awake, slow-wave sleep (SWS) and rapid-eye movement (REM) sleep states and prenatal choline status. The main finding was that SUP rats displayed increased power levels of gamma (30-100 Hz) band oscillations during all phases of the sleep/wake cycle. These findings are discussed within the context of a general review of neuronal oscillations (e.g., delta, theta, and gamma bands) and synchronization across multiple brain regions in relation to sleep-dependent memory consolidation in the hippocampus.

APOBEC3B-Mediated Cytidine Deamination Is Required for Estrogen Receptor Action in Breast Cancer

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Manikandan Periyasamy

2015-10-01

Full Text Available Estrogen receptor α (ERα is the key transcriptional driver in a large proportion of breast cancers. We report that APOBEC3B (A3B is required for regulation of gene expression by ER and acts by causing C-to-U deamination at ER binding regions. We show that these C-to-U changes lead to the generation of DNA strand breaks through activation of base excision repair (BER and to repair by non-homologous end-joining (NHEJ pathways. We provide evidence that transient cytidine deamination by A3B aids chromatin modification and remodelling at the regulatory regions of ER target genes that promotes their expression. A3B expression is associated with poor patient survival in ER+ breast cancer, reinforcing the physiological significance of A3B for ER action.

A Novel Regulator of Activation-Induced Cytidine Deaminase/APOBECs in Immunity and Cancer: Schrödinger’s CATalytic Pocket

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Mani Larijani

2017-04-01

Full Text Available Activation-induced cytidine deaminase (AID and its relative APOBEC3 cytidine deaminases boost immune response by mutating immune or viral genes. Because of their genome-mutating activities, AID/APOBECs are also drivers of tumorigenesis. Due to highly charged surfaces, extensive non-specific protein–protein/nucleic acid interactions, formation of polydisperse oligomers, and general insolubility, structure elucidation of these proteins by X-ray crystallography and NMR has been challenging. Hence, almost all available AID/APOBEC structures are of mutated and/or truncated versions. In 2015, we reported a functional structure for AID using a combined computational–biochemical approach. In so doing, we described a new regulatory mechanism that is a first for human DNA/RNA-editing enzymes. This mechanism involves dynamic closure of the catalytic pocket. Subsequent X-ray and NMR studies confirmed our discovery by showing that other APOBEC3s also close their catalytic pockets. Here, we highlight catalytic pocket closure as an emerging and important regulatory mechanism of AID/APOBEC3s. We focus on three sub-topics: first, we propose that variable pocket closure rates across AID/APOBEC3s underlie differential activity in immunity and cancer and review supporting evidence. Second, we discuss dynamic pocket closure as an ever-present internal regulator, in contrast to other proposed regulatory mechanisms that involve extrinsic binding partners. Third, we compare the merits of classical approaches of X-ray and NMR, with that of emerging computational–biochemical approaches, for structural elucidation specifically for AID/APOBEC3s.

Long-term improvements in sensory inhibition with gestational choline supplementation linked to α7 nicotinic receptors through studies in Chrna7 null mutation mice.

Science.gov (United States)

Stevens, Karen E; Choo, Kevin S; Stitzel, Jerry A; Marks, Michael J; Adams, Catherine E

2014-03-13

Perinatal choline supplementation has produced several benefits in rodent models, from improved learning and memory to protection from the behavioral effects of fetal alcohol exposure. We have shown that supplemented choline through gestation and lactation produces long-term improvement in deficient sensory inhibition in DBA/2 mice which models a similar deficit in schizophrenia patients. The present study extends that research by feeding normal or supplemented choline diets to DBA/2 mice carrying the null mutation for the α7 nicotinic receptor gene (Chrna7). DBA/2 mice heterozygotic for Chrna7 were bred together. Dams were placed on supplemented (5 gm/kg diet) or normal (1.1 gm/kg diet) choline at mating and remained on the specific diet until offspring weaning. Thereafter, offspring were fed standard rodent chow. Adult offspring were assessed for sensory inhibition. Brains were obtained to ascertain hippocampal α7 nicotinic receptor levels. Choline-supplemented mice heterozygotic or null-mutant for Chrna7 failed to show improvement in sensory inhibition. Only wildtype choline-supplemented mice showed improvement with the effect solely through a decrease in test amplitude. This supports the hypothesis that gestational-choline supplementation is acting through the α7 nicotinic receptor to improve sensory inhibition. Although there was a significant gene-dose-related change in hippocampal α7 receptor numbers, binding studies did not reveal any choline-dose-related change in binding in any hippocampal region, the interaction being driven by a significant genotype main effect (wildtype>heterozygote>null mutant). These data parallel a human study wherein the offspring of pregnant women receiving choline supplementation during gestation, showed better sensory inhibition than offspring of women on placebo. Published by Elsevier B.V.

Choline chloride based ionic liquid analogues as tool for the fabrication of agar films with improved mechanical properties

Science.gov (United States)

In the present paper, we test the suitability of Choline-Cl/urea (DES-U) and Choline-Cl/glycerol (DES-G) eutectic mixtures at 1:2 molar ratios for the production of agar biodegradable films. A three-step process is proposed: pre-solubilization of polymer in DES followed by compression-molding and s...

Genetic signatures in choline and 1-carbon metabolism are associated with the severity of hepatic steatosis

Science.gov (United States)

Corbin, Karen D.; Abdelmalek, Manal F.; Spencer, Melanie D.; da Costa, Kerry-Ann; Galanko, Joseph A.; Sha, Wei; Suzuki, Ayako; Guy, Cynthia D.; Cardona, Diana M.; Torquati, Alfonso; Diehl, Anna Mae; Zeisel, Steven H.

2013-01-01

Choline metabolism is important for very low-density lipoprotein secretion, making this nutritional pathway an important contributor to hepatic lipid balance. The purpose of this study was to assess whether the cumulative effects of multiple single nucleotide polymorphisms (SNPs) across genes of choline/1-carbon metabolism and functionally related pathways increase susceptibility to developing hepatic steatosis. In biopsy-characterized cases of nonalcoholic fatty liver disease and controls, we assessed 260 SNPs across 21 genes in choline/1-carbon metabolism. When SNPs were examined individually, using logistic regression, we only identified a single SNP (PNPLA3 rs738409) that was significantly associated with severity of hepatic steatosis after adjusting for confounders and multiple comparisons (P=0.02). However, when groupings of SNPs in similar metabolic pathways were defined using unsupervised hierarchical clustering, we identified groups of subjects with shared SNP signatures that were significantly correlated with steatosis burden (P=0.0002). The lowest and highest steatosis clusters could also be differentiated by ethnicity. However, unique SNP patterns defined steatosis burden irrespective of ethnicity. Our results suggest that analysis of SNP patterns in genes of choline/1-carbon metabolism may be useful for prediction of severity of steatosis in specific subsets of people, and the metabolic inefficiencies caused by these SNPs should be examined further.—Corbin, K. D., Abdelmalek, M. F., Spencer, M. D., da Costa, K.-A., Galanko, J. A., Sha, W., Suzuki, A., Guy, C. D., Cardona, D. M., Torquati, A., Diehl, A. M., Zeisel, S. H. Genetic signatures in choline and 1-carbon metabolism are associated with the severity of hepatic steatosis. PMID:23292069

Improving monoterpene geraniol production through geranyl diphosphate synthesis regulation in Saccharomyces cerevisiae.

Science.gov (United States)

Zhao, Jianzhi; Bao, Xiaoming; Li, Chen; Shen, Yu; Hou, Jin

2016-05-01

Monoterpenes have wide applications in the food, cosmetics, and medicine industries and have recently received increased attention as advanced biofuels. However, compared with sesquiterpenes, monoterpene production is still lagging in Saccharomyces cerevisiae. In this study, geraniol, a valuable acyclic monoterpene alcohol, was synthesized in S. cerevisiae. We evaluated three geraniol synthases in S. cerevisiae, and the geraniol synthase Valeriana officinalis (tVoGES), which lacked a plastid-targeting peptide, yielded the highest geraniol production. To improve geraniol production, synthesis of the precursor geranyl diphosphate (GPP) was regulated by comparing three specific GPP synthase genes derived from different plants and the endogenous farnesyl diphosphate synthase gene variants ERG20 (G) (ERG20 (K197G) ) and ERG20 (WW) (ERG20 (F96W-N127W) ), and controlling endogenous ERG20 expression, coupled with increasing the expression of the mevalonate pathway by co-overexpressing IDI1, tHMG1, and UPC2-1. The results showed that overexpressing ERG20 (WW) and strengthening the mevalonate pathway significantly improved geraniol production, while expressing heterologous GPP synthase genes or down-regulating endogenous ERG20 expression did not show positive effect. In addition, we constructed an Erg20p(F96W-N127W)-tVoGES fusion protein, and geraniol production reached 66.2 mg/L after optimizing the amino acid linker and the order of the proteins. The best strain yielded 293 mg/L geraniol in a fed-batch cultivation, a sevenfold improvement over the highest titer previously reported in an engineered S. cerevisiae strain. Finally, we showed that the toxicity of geraniol limited its production. The platform developed here can be readily used to synthesize other monoterpenes.

Choline-Deficient-Diet-Induced Fatty Liver Is a Metastasis-Resistant Microenvironment.

Science.gov (United States)

Nakamura, Miki; Suetsugu, Atsushi; Hasegawa, Kosuke; Matsumoto, Takuro; Aoki, Hitomi; Kunisada, Takahiro; Shimizu, Masahito; Saji, Shigetoyo; Moriwaki, Hisataka; Hoffman, Robert M

2017-07-01

Fatty liver disease is increasing in the developed and developing world. Liver metastasis from malignant lymphoma in the fatty liver is poorly understood. In a previous report, we developed color-coded imaging of the tumor microenvironment (TME) of the murine EL4-RFP malignant lymphoma during metastasis, including the lung. In the present report, we investigated the potential and microenvironment of the fatty liver induced by a choline-deficient diet as a metastatic site in this mouse lymphoma model. C57BL/6-GFP transgenic mice were fed with a choline-deficient diet in order to establish a fatty liver model. EL4-RFP cells were injected in the spleen of normal mice and fatty-liver mice. Metastases in mice with fatty liver or normal liver were imaged with the Olympus SZX7 microscope and the Olympus FV1000 confocal microscope. Metastases of EL4-RFP were observed in the liver, ascites and bone marrow. Primary tumors were imaged in the spleen at the injection site. The fewest metastases were observed in the fatty liver. In addition, the fewest cancer-associated fibroblasts (CAFs) were observed in the fatty liver. The relative metastatic resistance of the fatty liver may be due to the reduced number of CAFs in the fatty livers. The mechanism of the effect of the choline-deficient diet is discussed. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

Effect of quinolinic acid in the nucleus basalis magnocellularis on cortical high-affinity choline uptake

Energy Technology Data Exchange (ETDEWEB)

Metcalf, R.H.; Boegman, R.J.; Quirion, R.; Riopelle, R.J.; Ludwin, S.K.

1987-08-01

A transient 45% increase in cortical high-affinity choline uptake (HACU) was observed after an injection of quinolinic acid (QUIN) into the nucleus basalis magnocellularis (nbM) of the rat. This was followed by a steady decline in choline uptake, which resulted in a 46% decrease by day 7. Specific (/sup 3/H)hemicholinium-3 binding to coronal brain sections showed a similar pattern following injections of QUIN into the nbM. The increase in cortical HACU elicited by QUIN appeared to be dose dependent.

Eggs early in complementary feeding increase choline pathway biomarkers and DHA: a randomized controlled trial in Ecuador.

Science.gov (United States)

Iannotti, Lora L; Lutter, Chessa K; Waters, William F; Gallegos Riofrío, Carlos Andres; Malo, Carla; Reinhart, Gregory; Palacios, Ana; Karp, Celia; Chapnick, Melissa; Cox, Katherine; Aguirre, Santiago; Narvaez, Luis; López, Fernando; Sidhu, Rohini; Kell, Pamela; Jiang, Xuntian; Fujiwara, Hideji; Ory, Daniel S; Young, Rebecca; Stewart, Christine P

2017-12-01

Background: Choline status has been associated with stunting among young children. Findings from this study showed that an egg intervention improved linear growth by a length-for-age z score of 0.63. Objective: We aimed to test the efficacy of eggs introduced early in complementary feeding on plasma concentrations of biomarkers in choline pathways, vitamins B-12 and A, and essential fatty acids. Design: A randomized controlled trial, the Lulun ("egg" in Kichwa) Project, was conducted in a rural indigenous population of Ecuador. Infants aged 6-9 mo were randomly assigned to treatment (1 egg/d for 6 mo; n = 80) and control (no intervention; n = 83) groups. Socioeconomic data, anthropometric measures, and blood samples were collected at baseline and endline. Household visits were made weekly for morbidity surveillance. We tested vitamin B-12 plasma concentrations by using chemiluminescent competitive immunoassay and plasma concentrations of choline, betaine, dimethylglycine, retinol, essential fatty acids, methionine, dimethylamine (DMA), trimethylamine, and trimethylamine- N -oxide (TMAO) with the use of liquid chromatography-tandem mass spectrometry. Results: Socioeconomic factors and biomarker concentrations were comparable at baseline. Of infants, 11.4% were vitamin B-12 deficient and 31.7% marginally deficient at baseline. In adjusted generalized linear regression modeling, the egg intervention increased plasma concentrations compared with control by the following effect sizes: choline, 0.35 (95% CI: 0.12, 0.57); betaine, 0.29 (95% CI: 0.01, 0.58); methionine, 0.31 (95% CI: 0.03, 0.60); docosahexaenoic acid, 0.43 (95% CI: 0.13, 0.73); DMA, 0.37 (95% CI: 0.37, 0.69); and TMAO, 0.33 (95% CI: 0.08, 0.58). No significant group differences were found for vitamin B-12, retinol, linoleic acid (LA), α-linolenic acid (ALA), or ratios of betaine to choline and LA to ALA. Conclusion: The findings supported our hypothesis that early introduction of eggs significantly

Detection of choline transporter-like 1 protein CTL1 in neuroblastoma × glioma cells and in the CNS, and its role in choline uptake

Czech Academy of Sciences Publication Activity Database

Machová, Eva; O´Regan, S.; Newcombe, J.; Meunier, F. M.; Prentice, J.; Dove, R.; Lisá, Věra; Doležal, Vladimír

2009-01-01

Roč. 110, č. 4 (2009), s. 1297-1309 ISSN 0022-3042 R&D Projects: GA MŠk(CZ) LC554; GA AV ČR(CZ) IAA500110703 Institutional research plan: CEZ:AV0Z50110509 Keywords : CTL1 * choline * cell growth Subject RIV: ED - Physiology Impact factor: 3.999, year: 2009

11C-Choline PET/pathology image coregistration in primary localized prostate cancer

International Nuclear Information System (INIS)

Grosu, Anca-Ligia; Prokic, Vesna; Weirich, Gregor; Wendl, Christina; Geinitz, Hans; Molls, Michael; Kirste, Simon; Souvatzoglou, Michael; Schwaiger, Markus; Gschwend, Juergen E.; Treiber, Uwe; Weber, Wolfgang A.; Krause, Bernd Joachim

2014-01-01

The aim of this study was to develop a methodology for the comparison of pathology specimens after prostatectomy (post-S) with PET images obtained before surgery (pre-S). This method was used to evaluate the merit of 11 C-choline PET/CT for delineation of gross tumour volume (GTV) in prostate cancer (PC). In 28 PC patients, 11 C-choline PET/CT was performed before surgery. PET/CT data were coregistered with the pathology specimens. GTV on PET images (GTV-PET) was outlined automatically and corrected manually. Tumour volume in the prostate (TVP) was delineated manually on the pathology specimens. Based on the coregistered PET/pathology images, the following parameters were assessed: SUVmax and SUVmean in the tumoral and nontumoral prostate (NP), GTV-PET (millilitres) and TVP (millilitres). PET/pathology image coregistration was satisfactory. Mean SUVmax in the TVP was lower than in the NP: 5.0 and 5.5, respectively (p = 0.093). Considering the entire prostate, SUVmax was located in the TVP in two patients, in the TVP and NP in 12 patients and exclusively in NP in 14 patients. Partial overlap the TVP and GTV-PET was seen in 71 % of patients, and complete overlap in 4 %. PET/pathology image coregistration can be used for evaluation of different imaging modalities. 11 C-Choline PET failed to distinguish tumour from nontumour tissue. (orig.)

An efficient and green method for regio- and chemo-selective Friedel–Crafts acylations using a deep eutectic mixture ([CholineCl][ZnCl2]3)

DEFF Research Database (Denmark)

Hoang, Tran Phuong; Nguyen, Hai Truong; Hansen, Poul Erik

2016-01-01

[CholineCl][ZnCl2]3, a deep eutectic solvent between choline chloride and ZnCl2, has been used as a dual function catalyst and green solvent for the Friedel–Crafts acylation of aromatic compounds instead of using the moisture-sensitive Lewis acids and volatile organic solvents. The reactions...... are performed with high yields under microwave irradiation with short reaction times for the synthesis of ketones. Interestingly, indole derivatives are regioselectively acylated in the 3-position under mild conditions with high yields without NH protection. Three new ketone products are synthesized. [Choline......Cl][ZnCl2]3 is easily synthesized from choline chloride and zinc chloride at a low cost, with easy purification and environmentally benign compounds. [CholineCl][ZnCl2]3 can be reused up to five times without loss of catalytic activity, making it ideal in industrial processes....

[{sup 11}C]Choline PET/CT detection of bone metastases in patients with PSA progression after primary treatment for prostate cancer: comparison with bone scintigraphy

Energy Technology Data Exchange (ETDEWEB)

Picchio, Maria [San Raffaele Scientific Institute, Nuclear Medicine Department, Milan (Italy); National Research Council (IBFM-CNR), Institute for Bioimaging and Molecular Physiology, Milan (Italy); Spinapolice, Elena Giulia; Crivellaro, Cinzia [University of Milano-Bicocca, Center for Molecular Bioimaging, Milan (Italy); Fallanca, Federico; Gianolli, Luigi [San Raffaele Scientific Institute, Nuclear Medicine Department, Milan (Italy); Giovacchini, Giampiero [University of Milano-Bicocca, Center for Molecular Bioimaging, Milan (Italy); University Hospital Basel, Institute of Nuclear Medicine, Basel (Switzerland); Messa, Cristina [National Research Council (IBFM-CNR), Institute for Bioimaging and Molecular Physiology, Milan (Italy); University of Milano-Bicocca, Center for Molecular Bioimaging, Milan (Italy); San Gerardo Hospital, Department of Nuclear Medicine, Monza (Italy)

2012-01-15

The aim of this study was to evaluate the clinical usefulness of [{sup 11}C]choline positron emission tomography (PET)/CT in comparison with bone scintigraphy (BS) in detecting bone metastases (BM) of patients with biochemical progression after radical treatment for prostate cancer (PCa). Seventy-eight consecutive patients with biochemical progression of PCa (mean prostate-specific antigen 21.1 ng/ml, range 0.2-500.0 ng/ml) referred for both [{sup 11}C]choline PET/CT and BS for restaging purposes were retrospectively analysed. The diagnostic accuracy of [{sup 11}C]choline PET/CT and BS was assessed by using morphological imaging and/or follow-up as standards of reference. As equivocal findings were found, the accuracy analysis was performed twice, once including them as positive and once as negative. A separate analysis was also performed in hormone-resistant patients and data compared with those of patients who did not receive anti-androgenic treatment. Equivocal findings occurred in 1 of 78 (1%) cases in [{sup 11}C]choline PET/CT and in 21 of 78 (27%) cases in BS. Depending on their attribution as either positive or negative, the ranges of sensitivity, specificity, positive predictive value, negative predictive value and accuracy for [{sup 11}C]choline PET/CT were 89-89%, 98-100%, 96-100%, 94-96% and 95-96%, respectively. For BS they were 100-70%, 75-100%, 68-100%, 100-86% and 83-90%, respectively. Concordant findings between [{sup 11}C]choline PET/CT and BS occurred in 55 of 78 (71%) cases. The accuracy of [{sup 11}C]choline PET/CT did not significantly (p = 0.30) differ between hormone-resistant patients (97%) and those who did not receive anti-androgenic treatment (95%). In clinical practice, [{sup 11}C]choline PET/CT may not replace BS because of its lower sensitivity. However, for its high specificity, [{sup 11}C]choline PET/CT positive findings may accurately predict the presence of BM. Equivocal findings are more frequent in BS than [{sup 11}C]choline PET

Tenofovir-induced Fanconi syndrome and osteomalacia in two HIV-infected patients: Role of intracellular tenofovir diphosphate levels and review of the literature

NARCIS (Netherlands)

Haverkort, M.E.; van der Spek, B.W.; Lips, P.T.A.M.; Slieker, W.A.; ter Heine, R.; Huitema, A.D.; Bronsveld, W.

2011-01-01

We present 2 human immunodeficiency virus-infected patients with tenofovir disoproxil fumarate-induced Fanconi syndrome, leading to osteomalacia. Intracellular tenofovir diphosphate levels were measured in 1 patient and were found to be very high, with plasma tenofovir levels just slightly elevated.

Plasma immune protein analysis in the orange-spotted grouper Epinephelus coioides: Evidence for altered expressions of immune factors associated with a choline-supplemented diet.

Science.gov (United States)

Shiu, Ya-Li; Chiu, Kuo-Hsun; Huynh, Truong-Giang; Liu, Ping-Chung; Liu, Chun-Hung

2017-06-01

This study aimed to unravel the regulatory roles of choline in activating immune responses and disease resistance of the orange-spotted grouper Epinephelus coioides. Fish were fed a choline-supplemented diet at 1 g kg -1 of feed for 30 days. Fish fed a fish meal basal diet without choline-supplement served as controls. At the end of the feeding trial, fish were challenged with Vibrio alginolyticus. Meanwhile, plasma proteomics of fish in each group were also evaluated by two-dimensional gel electrophoresis (2-DE), and differentially expressed proteins were identified by tandem mass spectrophotometry (MS/MS), then a Western blot analysis or real-time polymerase chain reaction was used to confirm differential expressions of immune-enhancing proteins. Results showed that choline significantly increased survival of E. coioides 48 days after being injected with V. alginolyticus. From maps of plasma proteins, a comparative analysis between the control and choline groups revealed that 111 spots matched, with 26 altered expression spots in the choline group. Of these 26 spots, 16 were upregulated and 10 downregulated. After protein identification by reverse-phase nano-high-performance liquid chromatography-electrospray ionization MS/MS analysis, eight of 26 proteins were found to be immune-related proteins, all of which were upregulated, including complement 3 (C3), alpha-2-macroglobulin-P-like isoform (A2M), fibrinogen beta chain precursor (FBG), and immunoglobulin heavy constant mu (Ighm) proteins. Expression of the A2M protein and A2M enzyme activity in plasma of fish fed choline significantly increased compared to the control group. Additionally, A2M messenger (m)RNA transcripts were also upregulated in the liver and kidneys. Significantly higher C3 expressions at both the mRNA and protein levels were detected in the liver of fish in the choline group. Moreover, FBG gene expressions in the liver and kidneys significantly increased, while Ighm increased in the

Suppression Effects of Betaine-Enriched Spinach on Hyperhomocysteinemia Induced by Guanidinoacetic Acid and Choline Deficiency in Rats

Directory of Open Access Journals (Sweden)

Yi-Qun Liu

2014-01-01

Full Text Available Betaine is an important natural component of rich food sources, especially spinach. Rats were fed diets with betaine or spinach powder at the same level of betaine for 10 days to investigate the dose-dependent effects of spinach powder supplementation on hyperhomocysteinemia induced by guanidinoacetic acid (GAA addition and choline deprivation. The GAA-induced hyperhomocysteinemia in rats fed 25% casein diet (25C was significantly suppressed by supplementation with betaine or spinach, and it was completely suppressed by taking 11.0% spinach supplementation. The choline deprivation-induced enhancement of plasma homocysteine concentration in rats fed 25% soybean protein diet (25S was markedly suppressed by 3.82% spinach. Supplementation with betaine or spinach partially prevented the effects of GAA on hepatic concentrations of methionine metabolites. The decrease in activity of betaine-homocysteine S-methyltransferase (BHMT and cystathionine β-synthase (CBS in GAA-induced hyperhomocysteinemia was recovered by supplementation with betaine or spinach. Supplementation with betaine or spinach did not affect BHMT activity, whereas it partially restored CBS activity in choline-deprived 25S. The results indicated that betaine or spinach could completely suppress the hyperhomocysteinemia induced by choline deficiency resulting from stimulating the homocysteine removal by both remethylation and cystathionine formation.

The value of 18F-choline PET/CT in patients with elevated PSA-level and negative prostate needle biopsy for localisation of prostate cancer

International Nuclear Information System (INIS)

Igerc, I.; Kohlfuerst, S.; Gallowitsch, H.J.; Matschnig, S.; Kresnik, E.; Gomez-Segovia, I.; Lind, P.

2008-01-01

Patients with persistent elevated PSA and repeated negative prostate biopsy, that means having the prostate biopsied at multiple times, were investigated with 18F-choline PET/CT to delineate prostate cancer and guide renewed prostate biopsy. Twenty patients with elevated PSA and negative prostate biopsies underwent 18F-choline PET/CT. We performed an early examination of the pelvic region 3-5 min after application. After 30 minutes a whole body PET/CT examination was performed. Image analysis was performed visually and by semi-quantitative analysis calculating the maximum standardised uptake value (SUVmax). 18F-choline uptake was defined as focal, multifocal or inhomogeneous. After the 18F-choline PET/CT, all patients underwent a repeated prostate biopsy, and in the cases where a focal or multifocal uptake was found, the biopsy was guided by the result of the examination. Qualitative image analysis revealed focal 18F-choline uptake in 13 out of 20 patients. In five patients, prostate cancer was revealed by repeated aspiration biopsy. None of the patients with a multifocal or inhomogeneous 18F-choline uptake had a malignant neoplasm in the prostate. Semiquantitative analysis performed with SUVmax was not helpful in the discrimination of malignancy but showed high values also in benign prostate diseases, as well as in normal prostate tissue. The dual-phase protocol delivered no clear benefit in discriminating malignancy from benign alterations. The use of 18F-choline cannot be generally recommended for localising prostate cancer; however, in highly selected patients, we found useful additional information. In 25% of patients, 18F-choline PET/CT allowed the identification of neoplastic prostatic zones. (orig.)

Prostate cancer: a comparative study of {sup 11}C-choline PET and MR imaging combined with proton MR spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Yamaguchi, Takako; Lee, Jin; Takahashi, Nobukazu; Oka, Takashi; Shizukuishi, Kazuya; Inoue, Tomio [Yokohama City University School of Medicine, Department of Radiology, Yokohama (Japan); Uemura, Hiroji; Kubota, Yoshinobu [Yokohama City University School of Medicine, Department of Urology, Kanagawa (Japan); Sasaki, Takeshi [Yokohama City University School of Medicine, Department of Pathology, Kanagawa (Japan); Endou, Hisashi [Yokohama City University School of Medicine, Department of Pharmacy, Kanagawa (Japan)

2005-07-01

Prostate cancer is difficult to visualise in its early stages using current imaging technology. The present study aimed to clarify the utility of {sup 11}C-choline PET for localising and evaluating cancer lesions in patients with prostate cancer by conducting a prospective comparison with magnetic resonance (MR) imaging combined with proton MR spectroscopy. PET and MR imaging combined with proton MR spectroscopy were performed in 20 patients with prostate cancer. Correlations among the metabolite ratio of choline + creatine to citrate (Cho+Cr/Ci) on MR spectroscopy, serum PSA and maximum standardised uptake value (SUV{sub max}) of {sup 11}C-choline were assessed. The location of the primary lesion was assessed by the site of SUV{sub max} and the laterality of the highest Cho+Cr/Ci ratio and confirmed by examination of surgical pathology specimens (n=16). PET exhibited a diagnostic sensitivity of 100% (20/20) for primary lesions, while the sensitivities of MR imaging and MR spectroscopy were 60% (12/20) and 65% (13/20), respectively. Weak linear correlations were observed between SUV{sub max} and serum PSA (r=0.52, p<0.05), and between SUV{sub max} and Cho+Cr/Ci ratio (r=0.49, p<0.05). Regarding the localisation of main primary lesions, PET results agreed with pathological findings in 13 patients (81%) ({kappa}=0.59), while MR spectroscopy results were in accordance with pathological findings in eight patients (50%) ({kappa}=0.11). This preliminary study suggests that {sup 11}C-choline PET may provide more accurate information regarding the localisation of main primary prostate cancer lesions than MR imaging/MR spectroscopy. A further clinical study of {sup 11}C-choline PET in a large number of patients suspected of prostate cancer will be necessary to determine the clinical utility of {sup 11}C-choline PET in patients who clinically require biopsy. (orig.)

Choline and Working Memory Training Improve Cognitive Deficits Caused by Prenatal Exposure to Ethanol

Directory of Open Access Journals (Sweden)

Jaylyn Waddell

2017-09-01

Full Text Available Prenatal ethanol exposure is associated with deficits in executive function such as working memory, reversal learning and attentional set shifting in humans and animals. These behaviors are dependent on normal structure and function in cholinergic brain regions. Supplementation with choline can improve many behaviors in rodent models of fetal alcohol spectrum disorders and also improves working memory function in normal rats. We tested the hypothesis that supplementation with choline in the postnatal period will improve working memory during adolescence in normal and ethanol-exposed animals, and that working memory engagement during adolescence will transfer to other cognitive domains and have lasting effects on executive function in adulthood. Male and female offspring of rats fed an ethanol-containing liquid diet (ET; 3% v/v or control dams given a non-ethanol liquid diet (CT were injected with choline (Cho; 100 mg/kg or saline (Sal once per day from postnatal day (P 16–P30. Animals were trained/tested on a working memory test in adolescence and then underwent attentional set shifting and reversal learning in young adulthood. In adolescence, ET rats required more training to reach criterion than CT-Sal. Choline improved working memory performance for both CT and ET animals. In young adulthood, ET animals also performed poorly on the set shifting and reversal tasks. Deficits were more robust in ET male rats than female ET rats, but Cho improved performance in both sexes. ET male rats given a combination of Cho and working memory training in adolescence required significantly fewer trials to achieve criterion than any other ET group, suggesting that early interventions can cause a persistent improvement.

Study of the thorium phosphate-diphosphate (TPD) dissolution: kinetic aspect - thermodynamic aspect: analysis of the neo-formed phases; Etude de la dissolution du phosphate diphosphate de thorium: - aspect cinetique - aspect thermodynamique: analyse des phases neoformees

Energy Technology Data Exchange (ETDEWEB)

Thomas, A.Ch

2000-10-06

The aim of this work is to study the aqueous corrosion of the thorium phosphate-diphosphate (TPD), of the formula Th{sub 4}(PO{sub 4}){sub 4}P{sub 2}O{sub 7}, in the framework of the actinides immobilization. In order to complete the anterior studies concerning solid solutions where thorium is substituted by a tetravalent ion (uranium (IV) or plutonium (IV)) in the TPD structure, compounds of thorium and neptunium phosphate-diphosphate, of formula Th{sub 4-x}Np{sub x}(PO{sub 4}){sub 4}P{sub 2}O{sub 7}, have been prepared. Furthermore, a new chemical way of synthesis has been investigated in order to sinter solids solution of thorium and uranium phosphate-diphosphate (TUPD) in good conditions. The TPD dissolution study showed two principals steps. The first one corresponds to the control of element concentration by the material dissolution whereas the second corresponds to the formation of secondary precipitates for which thermodynamic equilibrium controls the concentration of the species in solution. Leaching tests have been performed varying several independent parameters in order to determine the TPD dissolution rate. The partial orders related to the protons or to the hydroxide ions have been found between 0.35 and 0.45 whereas the apparent dissolution rate constants are in the range 1.10{sup -5} for 9.10{sup -5} g.m{sup -2}.j{sup -1} for acidic and basic media. The neo-formed phases have been characterized after the dissolution of TPD and TUPD. We found that the TPD leaching in acidic medium leads to the formation of the crystallized thorium phosphate-hydrogen-phosphate (TPHP), of formula Th{sub 2}(PO{sub 4}){sub 2}(HPO{sub 4}), x H{sub 2}O, whereas the TUPD dissolution leads to the TPHP and an other compound, of formula (UO{sub 2}){sub 3}(PO{sub 4}){sub 2}, 5 H{sub 2}O. We calculated its solubility product which is in good agreement with those found in the literature. The phases formed during the leaching of solids containing plutonium; americium or curium (Th

Crystallization and preliminary X-ray diffraction studies of choline-binding protein F from Streptococcus pneumoniae

Energy Technology Data Exchange (ETDEWEB)

Molina, Rafael [Grupo de Cristalografía Macromolecular y Biología Estructural, Instituto Química Física Rocasolano, CSIC, Serrano 119, 28006 Madrid (Spain); González, Ana; Moscoso, Miriam; García, Pedro [Departamento de Microbiología Molecular, Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, 28040 Madrid (Spain); Stelter, Meike; Kahn, Richard [Institut de Biologie Structurale J.-P. Ebel CEA CNRS UJF, Laboratoire de Cristallographie Macromoléculaire, 41 Rue Jules Horowitz, 38027 Grenoble CEDEX 1 (France); Hermoso, Juan A., E-mail: xjuan@iqfr.csic.es [Grupo de Cristalografía Macromolecular y Biología Estructural, Instituto Química Física Rocasolano, CSIC, Serrano 119, 28006 Madrid (Spain)

2007-09-01

The modular choline-binding protein F (CbpF) from S. pneumoniae has been crystallized by the hanging-drop vapour-diffusion method. A SAD data set from a gadolinium-complex derivative has been collected to 2.1 Å resolution. Choline-binding protein F (CbpF) is a modular protein that is bound to the pneumococcal cell wall through noncovalent interactions with choline moieties of the bacterial teichoic and lipoteichoic acids. Despite being one of the more abundant proteins on the surface, along with the murein hydrolases LytA, LytB, LytC and Pce, its function is still unknown. CbpF has been crystallized using the hanging-drop vapour-diffusion method at 291 K. Diffraction-quality orthorhombic crystals belong to space group P2{sub 1}2{sub 1}2, with unit-cell parameters a = 49.13, b = 114.94, c = 75.69 Å. A SAD data set from a Gd-HPDO3A-derivatized CbpF crystal was collected to 2.1 Å resolution at the gadolinium L{sub III} absorption edge using synchrotron radiation.

Crystallization and preliminary X-ray diffraction studies of choline-binding protein F from Streptococcus pneumoniae

International Nuclear Information System (INIS)

Molina, Rafael; González, Ana; Moscoso, Miriam; García, Pedro; Stelter, Meike; Kahn, Richard; Hermoso, Juan A.

2007-01-01

The modular choline-binding protein F (CbpF) from S. pneumoniae has been crystallized by the hanging-drop vapour-diffusion method. A SAD data set from a gadolinium-complex derivative has been collected to 2.1 Å resolution. Choline-binding protein F (CbpF) is a modular protein that is bound to the pneumococcal cell wall through noncovalent interactions with choline moieties of the bacterial teichoic and lipoteichoic acids. Despite being one of the more abundant proteins on the surface, along with the murein hydrolases LytA, LytB, LytC and Pce, its function is still unknown. CbpF has been crystallized using the hanging-drop vapour-diffusion method at 291 K. Diffraction-quality orthorhombic crystals belong to space group P2 1 2 1 2, with unit-cell parameters a = 49.13, b = 114.94, c = 75.69 Å. A SAD data set from a Gd-HPDO3A-derivatized CbpF crystal was collected to 2.1 Å resolution at the gadolinium L III absorption edge using synchrotron radiation

The use of choline in association with the Bangerter filters for the treatment of amblyopia

Directory of Open Access Journals (Sweden)

Lelio Sabetti

2017-11-01

Full Text Available The study investigated the effects of choline combined with Bangerter filter in the treatment of amblyopia. All amblyopic subjects used a Bangerter filter on the corrective spectacle lens (1d over the left eye, 1d over the right eye. Choline was then administered orally to 39 patients once daily, five days per week for the entire study period. Subjects treated with the Bangerter filter showed a mean visual acuity of 0.27 logMAR; at 12mo of treatment, the mean visual acuity reached 0.09 logMAR. Patients treated with the Bangerter filter and citicoline showed a mean visual acuity of 0.35 logMAR; at 12mo of treatment, the mean visual acuity reached 0.01 logMAR. No significant changes in the angle of deviation were observed in both groups. Subjects in both forms of amblyopia therapies demonstrated an increase in visual acuity. However, these effects were markedly enhanced when coupled with the administration of choline. Findings suggest that the effects are particularly relevant in the more severe amblyopic cases.

Quantification of acetylcholine, choline, betaine, and dimethylglycine in human plasma and urine using stable-isotope dilution ultra performance liquid chromatography-tandem mass spectrometry.

Science.gov (United States)

Kirsch, Susanne H; Herrmann, Wolfgang; Rabagny, Yannick; Obeid, Rima

2010-12-15

Disorders in choline metabolism are related to disease conditions. We developed a stable-isotope dilution ultra performance liquid chromatography-mass spectrometry (UPLC-MS/MS) method for the simultaneous quantification of acetylcholine (ACh), betaine, choline, and dimethylglycine (DMG). We used this method to measure concentrations of the analytes in plasma and urine in addition to other biological fluids after a protein precipitation by acetonitrile. The detection limits were between 0.35 nmol/L (for ACh in urine) and 0.34 μmol/L (for betaine in urine). ACh concentrations were not detectable in plasma. Intraassay and interassay coefficient of variation (CVs) were all DMG in cerebrospinal fluid (CV=12.44%). Mean recoveries in urine pool samples were between 99.2% and 103.9%. The urinary excretion of betaine, choline, and DMG was low, with approximately 50.0% higher excretion of choline in females compared to males. Median urinary excretion of ACh were 3.44 and 3.92 μmol/mol creatinine in males and females, respectively (p=0.689). Plasma betaine concentrations correlated significantly with urinary excretions of betaine (r=0.495, p=0.027) and choline (r=0.502, p=0.024) in females. Plasma choline concentrations correlated significantly with urinary excretion of ACh in males (r=0.419, p=0.041) and females (r=0.621, p=0.003). The new method for the simultaneous determination of ACh, betaine, choline, and DMG is sensitive, precise, and fast enough to be used in clinical investigations related to the methylation pathway. Copyright © 2010 Elsevier B.V. All rights reserved.

Distinct choline metabolic profiles are associated with differences in gene expression for basal-like and luminal-like breast cancer xenograft models

International Nuclear Information System (INIS)

Moestue, Siver A; Borgan, Eldrid; Huuse, Else M; Lindholm, Evita M; Sitter, Beathe; Børresen-Dale, Anne-Lise; Engebraaten, Olav; Mælandsmo, Gunhild M; Gribbestad, Ingrid S

2010-01-01

Increased concentrations of choline-containing compounds are frequently observed in breast carcinomas, and may serve as biomarkers for both diagnostic and treatment monitoring purposes. However, underlying mechanisms for the abnormal choline metabolism are poorly understood. The concentrations of choline-derived metabolites were determined in xenografted primary human breast carcinomas, representing basal-like and luminal-like subtypes. Quantification of metabolites in fresh frozen tissue was performed using high-resolution magic angle spinning magnetic resonance spectroscopy (HR MAS MRS). The expression of genes involved in phosphatidylcholine (PtdCho) metabolism was retrieved from whole genome expression microarray analyses. The metabolite profiles from xenografts were compared with profiles from human breast cancer, sampled from patients with estrogen/progesterone receptor positive (ER+/PgR+) or triple negative (ER-/PgR-/HER2-) breast cancer. In basal-like xenografts, glycerophosphocholine (GPC) concentrations were higher than phosphocholine (PCho) concentrations, whereas this pattern was reversed in luminal-like xenografts. These differences may be explained by lower choline kinase (CHKA, CHKB) expression as well as higher PtdCho degradation mediated by higher expression of phospholipase A2 group 4A (PLA2G4A) and phospholipase B1 (PLB1) in the basal-like model. The glycine concentration was higher in the basal-like model. Although glycine could be derived from energy metabolism pathways, the gene expression data suggested a metabolic shift from PtdCho synthesis to glycine formation in basal-like xenografts. In agreement with results from the xenograft models, tissue samples from triple negative breast carcinomas had higher GPC/PCho ratio than samples from ER+/PgR+ carcinomas, suggesting that the choline metabolism in the experimental models is representative for luminal-like and basal-like human breast cancer. The differences in choline metabolite

Prospective head-to-head comparison of 11C-choline-PET/MR and 11C-choline-PET/CT for restaging of biochemical recurrent prostate cancer

International Nuclear Information System (INIS)

Eiber, Matthias; Rauscher, Isabel; Souvatzoglou, Michael; Schwaiger, Markus; Maurer, Tobias; Holzapfel, Konstantin; Beer, Ambros J.

2017-01-01

Whole-body integrated 11 C-choline PET/MR might provide advantages compared to 11 C-choline PET/CT for restaging of prostate cancer (PC) due to the high soft-tissue contrast and the use of multiparametric MRI, especially for detection of local recurrence and bone metastases. Ninety-four patients with recurrent PC underwent a single-injection/dual-imaging protocol with contrast-enhanced PET/CT followed by fully diagnostic PET/MR. Imaging datasets were read separately by two reader teams (team 1 and 2) assessing the presence of local recurrence, lymph node and bone metastases in predefined regions using a five-point scale. Detection rates were calculated. The diagnostic performance of PET/CT vs. PET/MR was compared using ROC analysis. Inter-observer and inter-modality variability, radiation exposure, and mean imaging time were evaluated. Clinical follow-up, imaging, and/or histopathology served as standard of reference (SOR). Seventy-five patients qualified for the final image analysis. A total of 188 regions were regarded as positive: local recurrence in 37 patients, 87 regions with lymph node metastases, and 64 regions with bone metastases. Mean detection rate between both readers teams for PET/MR was 84.7% compared to 77.3% for PET/CT (p > 0.05). Local recurrence was identified significantly more often in PET/MR compared to PET/CT by team 1. Lymph node and bone metastases were identified significantly more often in PET/CT compared to PET/MR by both teams. However, this difference was not present in the subgroup of patients with PSA values ≤2 ng/ml. Inter-modality and inter-observer agreement (K > 0.6) was moderate to substantial for nearly all categories. Mean reduction of radiation exposure for PET/MR compared to PET/CT was 79.7% (range, 72.6-86.2%). Mean imaging time for PET/CT was substantially lower (18.4 ± 0.7 min) compared to PET/MR (50.4 ± 7.9 min). 11 C-choline PET/MR is a robust imaging modality for restaging biochemical recurrent PC and

Choline Deficiency Causes Colonic Type II Natural Killer T (NKT) Cell Loss and Alleviates Murine Colitis under Type I NKT Cell Deficiency.

Science.gov (United States)

Sagami, Shintaro; Ueno, Yoshitaka; Tanaka, Shinji; Fujita, Akira; Niitsu, Hiroaki; Hayashi, Ryohei; Hyogo, Hideyuki; Hinoi, Takao; Kitadai, Yasuhiko; Chayama, Kazuaki

2017-01-01

Serum levels of choline and its derivatives are lower in patients with inflammatory bowel disease (IBD) than in healthy individuals. However, the effect of choline deficiency on the severity of colitis has not been investigated. In the present study, we investigated the role of choline deficiency in dextran sulfate sodium (DSS)-induced colitis in mice. Methionine-choline-deficient (MCD) diet lowered the levels of type II natural killer T (NKT) cells in the colonic lamina propria, peritoneal cavity, and mesenteric lymph nodes, and increased the levels of type II NKT cells in the livers of wild-type B6 mice compared with that in mice fed a control (CTR) diet. The gene expression pattern of the chemokine receptor CXCR6, which promotes NKT cell accumulation, varied between colon and liver in a manner dependent on the changes in the type II NKT cell levels. To examine the role of type II NKT cells in colitis under choline-deficient conditions, we assessed the severity of DSS-induced colitis in type I NKT cell-deficient (Jα18-/-) or type I and type II NKT cell-deficient (CD1d-/-) mice fed the MCD or CTR diets. The MCD diet led to amelioration of inflammation, decreases in interferon (IFN)-γ and interleukin (IL)-4 secretion, and a decrease in the number of IFN-γ and IL-4-producing NKT cells in Jα18-/- mice but not in CD1d-/- mice. Finally, adaptive transfer of lymphocytes with type II NKT cells exacerbated DSS-induced colitis in Jα18-/- mice with MCD diet. These results suggest that choline deficiency causes proinflammatory type II NKT cell loss and alleviates DSS-induced colitis. Thus, inflammation in DSS-induced colitis under choline deficiency is caused by type II NKT cell-dependent mechanisms, including decreased type II NKT cell and proinflammatory cytokine levels.

Improved Diagnostic Accuracy in Characterization of Adnexal Masses by Detection of Choline Peak Using 1H MR Spectroscopy in Comparison to Internal Reference at 3 Tesla.

Science.gov (United States)

Malek, Mahrooz; Pourashraf, Maryam; Gilani, Mitra Modares; Gity, Masoumeh

2015-01-01

The aim of this study was to assess the role of the presence of a choline peak in 3 Tesla 1H magnetic resonance spectroscopy (MRS) for differentiating benign from malignant adnexal masses. A total of 46 adnexal masses (23 malignant and 23 benign) underwent 1H MRS study prior to surgery to assess the presence of choline peak. A choline peak was detected in 16 malignant masses (69.5%) and was absent in the other 7 (30.5%). A choline peak was only detected in 6 (26%) of the benign adnexal masses. The presence of an MRS choline peak had a sensitivity of 69.5%, a specificity of 74%, a positive predictive value (PPV) of 72.7%, and a negative predictive value (NPV) of 71% for diagnosing malignant adnexal masses. A significant difference between the frequency of mean choline peaks in benign and malignant adnexal masses was observed (P valuepeak is seen in malignant adnexal masses more frequently than the benign masses, and may be helpful for diagnosing malignant adnexal masses.

Enhanced Bacterial α(2,6-Sialyltransferase Reaction through an Inhibition of Its Inherent Sialidase Activity by Dephosphorylation of Cytidine-5'-Monophosphate.

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Ji-Yeon Kang

Full Text Available Bacterial α(2,6-sialyltransferases (STs from Photobacterium damsela, Photobacterium sp. JT-ISH-224, and P. leiognathi JT-SHIZ-145 were recombinantly expressed in Escherichia coli and their ST activities were compared directly using a galactosylated bi-antennary N-glycan as an acceptor substrate. In all ST reactions, there was an increase of sialylated glycans at shorter reaction times and later a decrease in prolonged reactions, which is related with the inherent sialidase activities of bacterial STs. These sialidase activities are greatly increased by free cytidine monophosphate (CMP generated from a donor substrate CMP-N-acetylneuraminic acid (CMP-Neu5Ac during the ST reactions. The decrease of sialylated glycans in prolonged ST reaction was prevented through an inhibition of sialidase activity by simple treatment of alkaline phosphatase (AP, which dephosphorylates CMP to cytidine. Through supplemental additions of AP and CMP-Neu5Ac to the reaction using the recombinant α(2,6-ST from P. leiognathi JT-SHIZ-145 (P145-ST, the content of bi-sialylated N-glycan increased up to ~98% without any decrease in prolonged reactions. This optimized P145-ST reaction was applied successfully for α(2,6-sialylation of asialofetuin, and this resulted in a large increase in the populations of multi-sialylated N-glycans compared with the reaction without addition of AP and CMP-Neu5Ac. These results suggest that the optimized reaction using the recombinant P145-ST readily expressed from E. coli has a promise for economic glycan synthesis and glyco-conjugate remodeling.

Effect of choline on antioxidant defenses and gene expressions of Nrf2 signaling molecule in the spleen and head kidney of juvenile Jian carp (Cyprinus carpio var. Jian).

Science.gov (United States)

Wu, Pei; Jiang, Wei-Dan; Liu, Yang; Chen, Gang-Fu; Jiang, Jun; Li, Shu-Hong; Feng, Lin; Zhou, Xiao-Qiu

2014-06-01

The present work evaluates the effects of various levels of dietary choline on antioxidant defenses and gene expressions of Nrf2 signaling molecule in spleen and head kidney of juvenile Jian carp (Cyprinus carpio var. Jian). Fish were fed with six different experimental diets containing graded levels of choline at 165 (choline-deficient control), 310, 607, 896, 1167 and 1820 mg kg(-1) diet for 65 days. At the end of the feeding trail, fish were challenged with Aeromonas hydrophila and mortalities were recorded over 17 days. Dietary choline significantly decreased malondialdehyde and protein carbonyl contents in spleen and head kidney. However, anti-superoxide anion and anti-hydroxyl radical activities in spleen and head kidney also decreased. Interestingly, activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione-S-transferase (GST) and glutathione reductase (GR) in spleen, GPx activity in head kidney, and glutathione contents in spleen and head kidney were decreased with increase of dietary choline levels up to a certain point, whereas, activities of SOD, GST and GR in head kidney showed no significantly differences among groups. Similarly, expression levels of CuZnSOD, MnSOD, CAT, GPx1a, GPx1b and GR gene in spleen and head kidney were significantly lower in group with choline level of 607 mg kg(-1) diet than those in the choline-deficient group. The relative gene expressions of Nrf2 in head kidney and Keap1a in spleen and head kidney were decreased with increasing of dietary choline up to a certain point. However, the relative gene expression of Nrf2 in spleen were not significantly affected by dietary choline. In conclusion, dietary choline decreased the oxidant damage and regulated the antioxidant system in immune organs of juvenile Jian carp. Copyright © 2014 Elsevier Ltd. All rights reserved.

Evaluation of 11C-choline PET/CT for primary diagnosis and staging of urothelial carcinoma of the upper urinary tract: a pilot study

International Nuclear Information System (INIS)

Sassa, Naoto; Yamamoto, Tokunori; Gotoh, Momokazu; Kato, Katsuhiko; Ikeda, Mitsuru; Shimamoto, Kazuhiro; Yamamoto, Seiichi; Abe, Shinji; Iwano, Shingo; Ito, Shinji; Naganawa, Shinji

2014-01-01

We conducted a pilot study to prospectively evaluate the efficacy of PET/CT with 11 C-choline (choline PET/CT) for primary diagnosis and staging of urothelial carcinoma of the upper urinary tract (UUT-UC). Enrolled in this study were 16 patients (9 men, 7 women; age range 51 - 83 years, mean ± SD 69 ± 10.8 years) with suspected UUT-UC. The patients were examined by choline PET/CT, and 13 underwent laparoscopic nephroureterectomy and partial cystectomy. Lymphadenectomy and chemotherapy were also performed as necessary in some of the patients. Of the 16 patients, 12 were confirmed to have UUT-UC (7 renal pelvis carcinoma and 5 ureteral carcinoma), 1 had malignant lymphoma (ureter), 1 had IgG4-related disease (ureter), and 2 had other benign diseases (ureter). Of the 16 study patients, 13 showed definite choline uptake in urothelial lesions, and of these, 11 had UUT-UC, 1 had malignant lymphoma, and 1 had IgG4-related disease. Three patients without choline uptake comprised one with UUT-UC and two with benign diseases. Of the 12 patients with UUT-UC, 3 had distant metastases, 2 had metastases only in the regional lymph nodes, and 7 had no metastases. Distant metastases and metastases in the regional lymph nodes showed definite choline uptake. The outcome in patients with UUT-UC, which was evaluated 592 - 1,530 days after surgery, corresponded to the patient classification based on the presence or absence of metastases and locoregional or distant metastases. Choline uptake determined as SUVmax 10 min after administration was significantly higher than at 20 min in metastatic tumours of UUT-UC (p < 0.05), whereas there was no statistically significant difference between the SUVmax values at 10 and those at 20 min in primary tumours of UUT-UC. This study suggests that choline PET/CT is a promising tool for the primary diagnosis and staging of UUT-UC. (orig.)

(18)F-choline PET/CT pitfalls in image interpretation: an update on 300 examined patients with prostate cancer.

Science.gov (United States)

Calabria, Ferdinando; Chiaravalloti, Agostino; Schillaci, Orazio

2014-02-01

F-choline PET/CT is an important diagnostic tool in the management of patients with prostate cancer (PC). The aim of this study was to describe and discuss some abnormal sites of uptake that we observed, not due to PC recurrence. Three hundred patients were submitted to F-choline PET/CT for staging or restaging of PC. Whole-body PET/CT was acquired 40 minutes after the F-choline administration. We found abnormal uptake of the tracer, not related to PC, in 48/300 patients (16%). Most of these findings were due to inflammatory processes. Furthermore, some malignant conditions, such as a case of colon cancer, a case of bladder carcinoma, and a multiple myeloma, were diagnosed. Mild uptake was also detected in some benign diseases, such as thymoma, adrenal adenoma, and sarcoidosis. Six patients showed focal brain uptake in correspondence to a meningioma. It is necessary for nuclear physicians, during clinical practice, to consider the possibility of F-choline uptake in some benign or malignant conditions for the intrinsic pharmacologic property of the tracer. An accurate medical investigation, correlative imaging with CT and/or MRI with contrast agents, laboratory data, and above all, histologic examination are often necessary for correct diagnosis.

Role of Choline-Docosahexaenoic acid and Trigonella foenum graecum Seed Extract on Ovariectomy Induced Dyslipidemia and Oxidative Stress in Rat Model

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Nagamma Takkella

2018-01-01

Full Text Available Background: Menopause is characterized by the deficiency of ovarian hormones, mainly estrogen. The decline in estrogen hormone is contributing the cardiovascular disorders in women. Hormone replacement therapy has disadvantages especially a higher risk of breast, ovarian and endometrial cancers upon chronic use. Phytoestrogens may be used as an alternative to hormone replacement therapy. Aim and Objectives: This study was designed to scientifically evaluate the role of Choline- Docosahexaenoic Acid (DHA and Trigonella foenum graecum (TFG seed extract on Ovariectomy (OVX induced dyslipidemia and oxidative stress in rat model. Material and Methods: Female Wistar rats were allocated into four groups (n=6:1 Sham control, 2 ovariectomized, 3 ovariectomized+ choline-DHA and 4 ovariectomized + choline-DHA+TFG. After 30 days of treatment, fasting blood samples and liver tissues were collected. Serum was analyzed for lipid profile and liver homogenates were used for assessment of oxidative stress and antioxidant activity. Results: Ovariectomized rats showed significantly increased (P<0.05 Total Cholesterol (TC, Low Density Lipoprotein (LDL levels and decreased High Density Lipoprotein (HDL levels. Treating ovariectomized rats with choline-DHA and TFG seed extract significantly lowered (P<0.05 total cholesterol, LDL and markedly increased the HDL. Significantly increased (P≤0.01 Thiobarbituric Acid Reactive Substances (TBARS and reduced (P<0.05 glutathione levels were observed in OVX group. The synergetic effect of choline-DHA and fenugreek showed a significant reduction ((P≤0.01 in TBARS levels. Conclusion: These results showed that choline-DHA with TFG supplementation have a favorable effect on OVX induced hyperlipidemia and oxidative stress. Therefore, these components may be a therapeutic agent for treating the menopause induced hyperlipidemia or oxidative stress.

A recruiting protein of geranylgeranyl diphosphate synthase controls metabolic flux toward chlorophyll biosynthesis in rice.

Science.gov (United States)

Zhou, Fei; Wang, Cheng-Yuan; Gutensohn, Michael; Jiang, Ling; Zhang, Peng; Zhang, Dabing; Dudareva, Natalia; Lu, Shan

2017-06-27

In plants, geranylgeranyl diphosphate (GGPP) is produced by plastidic GGPP synthase (GGPPS) and serves as a precursor for vital metabolic branches, including chlorophyll, carotenoid, and gibberellin biosynthesis. However, molecular mechanisms regulating GGPP allocation among these biosynthetic pathways localized in the same subcellular compartment are largely unknown. We found that rice contains only one functionally active GGPPS, OsGGPPS1, in chloroplasts. A functionally active homodimeric enzyme composed of two OsGGPPS1 subunits is located in the stroma. In thylakoid membranes, however, the GGPPS activity resides in a heterodimeric enzyme composed of one OsGGPPS1 subunit and GGPPS recruiting protein (OsGRP). OsGRP is structurally most similar to members of the geranyl diphosphate synthase small subunit type II subfamily. In contrast to members of this subfamily, OsGRP enhances OsGGPPS1 catalytic efficiency and specificity of GGPP production on interaction with OsGGPPS1. Structural biology and protein interaction analyses demonstrate that affinity between OsGRP and OsGGPPS1 is stronger than between two OsGGPPS1 molecules in homodimers. OsGRP determines OsGGPPS1 suborganellar localization and directs it to a large protein complex in thylakoid membranes, consisting of geranylgeranyl reductase (OsGGR), light-harvesting-like protein 3 (OsLIL3), protochlorophyllide oxidoreductase (OsPORB), and chlorophyll synthase (OsCHLG). Taken together, genetic and biochemical analyses suggest OsGRP functions in recruiting OsGGPPS1 from the stroma toward thylakoid membranes, thus providing a mechanism to control GGPP flux toward chlorophyll biosynthesis.

Opioid receptor subtypes mediating the noise-induced decreases in high-affinity choline uptake in the rat brain.

Science.gov (United States)

Lai, H; Carino, M A

1992-07-01

Acute (20 min) exposure to 100-dB white noise elicits a naltrexone-sensitive decrease in sodium-dependent high-affinity choline uptake in the frontal cortex and hippocampus of the rat. In the present study, the subtypes of opioid receptors involved were investigated by pretreating rats with microinjection of specific opioid-receptor antagonists into the lateral cerebroventricle before noise exposure. We found that the noise-induced decrease in high-affinity choline uptake in the hippocampus was blocked by pretreatment with either mu-, delta-, or kappa-opioid-receptor antagonists, whereas the effect of noise on frontal cortical high-affinity choline uptake was blocked by a mu- and delta- but not by a kappa-antagonist. These data further confirm the role of endogenous opioids in mediating the effects of noise on central cholinergic activity and indicate that different neural mechanisms are involved in the effects of noise on the frontal cortical and hippocampal cholinergic systems.

Choline Modulation of the Aβ P1-40 Channel Reconstituted into a Model Lipid Membrane

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Daniela Meleleo

2010-01-01

Full Text Available Nicotinic acetylcholine receptors (AChRs, implicated in memory and learning, in subjects affected by Alzheimer's disease result altered. Stimulation of α7-nAChRs inhibits amyloid plaques and increases ACh release. β-amyloid peptide (AβP forms ion channels in the cell and model phospholipid membranes that are retained responsible in Alzheimer disease. We tested if choline, precursor of ACh, could affect the AβP1-40 channels in oxidized cholesterol (OxCh and in palmitoyl-oleoyl-phosphatidylcholine (POPC:Ch lipid bilayers. Choline concentrations of 5 × 10−11 M–1.5 × 10−8 M added to the cis- or trans-side of membrane quickly increased AβP1-40 ion channel frequency (events/min and ion conductance in OxCh membranes, but not in POPC:Ch membranes. Circular Dichroism (CD spectroscopy shows that after 24 and 48 hours of incubation with AβP1-40, choline stabilizes the random coil conformation of the peptide, making it less prone to fibrillate. These actions seem to be specific in that ACh is ineffective either in solution or on AβP1-40 channel incorporated into PLMs.

Analysis of quinocide in unprocessed primaquine diphosphate and primaquine diphosphate tablets using gas chromatography-mass spectrometry with supersonic molecular beams.

Science.gov (United States)

Brondz, Ilia; Fialkov, Alexander B; Amirav, Aviv

2009-01-30

Malaria is one of the most widespread and deadly diseases on the planet. Every year, about 500 million new cases are diagnosed, and the annual death toll is about 3 million. Primaquine has strong antiparasitic effects against gametocytes and can therefore prevent the spread of the parasite from treated patients to mosquitoes. It is also used in radical cures and prevents relapse. Consequently, primaquine is an often-used drug. In this study the separation of unprocessed primaquine from the contaminant quinocide based on gas chromatography-mass spectrometry with supersonic molecular beam (SMB) is presented and 7.5 mg primaquine diphosphate tablets were analyzed. We present a novel method for fast determination of quinocide which is an isomer of primaquine as the main contaminant in unprocessed primaquine and in its medical form as tablets by gas chromatography-mass spectrometry with SMB (also named supersonic GC-MS). Supersonic GC-MS provides enhanced molecular ion without any ion source related peak tailing plus extended range of compounds amenable for GC-MS analysis. In addition, major isomer mass spectral effects were revealed in the mass spectra of primaquine and quinocide which facilitated the unambiguous identification of quinocide in primaquine tablets. Fast GC-MS analysis is demonstrated with less then 2 min elution time of the drug and its main contaminants.

Escherichia coli phnN, encoding ribose 1,5-bisphosphokinase activity (phosphoribosyl diphosphate forming): dual role in phosphonate degradation and NAD biosynthesis pathways

DEFF Research Database (Denmark)

Hove-Jensen, Bjarne; Rosenkrantz, Tina J; Haldimann, Andreas

2003-01-01

An enzymatic pathway for synthesis of 5-phospho-D-ribosyl alpha-1-diphosphate (PRPP) without the participation of PRPP synthase was analyzed in Escherichia coli. This pathway was revealed by selection for suppression of the NAD requirement of strains with a deletion of the prs gene, the gene...

75 FR 760 - Choline chloride; Exemption from the Requirement of a Tolerance

Science.gov (United States)

2010-01-06

... affected. The North American Industrial Classification System (NAICS) codes have been provided to assist... body functions including the maintenance of osmotic pressure, acid-base balance, muscular activity, and... nervous system and memory. Choline is necessary to promote proper development in the fetus and infant and...

Autosomal recessive hyper IgM syndrome associated with activation-induced cytidine deaminase gene in three Turkish siblings presented with tuberculosis lymphadenitis - Case report.

Science.gov (United States)

Patiroglu, Turkan; Akar, H Haluk; van der Burg, Mirjam; Unal, Ekrem

2015-09-01

The hyper-immunoglobulin M (HIGM) syndrome is a heterogeneous group of genetic disorders characterized by recurrent infections, decreased serum levels of immunoglobulin G (IgG) and IgA, and normal/increased serum levels of IgM. Herein, we describe three Turkish siblings with HIGM syndrome who had a homozygous missense mutation (c.70C>T, p.Arg24Trp) in the activation-induced cytidine deaminase gene which results in autosomal recessive HIGM syndrome. Two of the siblings, sibling 1 and sibling 3, presented with cervical deep abscess and cervical tuberculosis lymphadenitis, respectively.

Prospective head-to-head comparison of {sup 11}C-choline-PET/MR and {sup 11}C-choline-PET/CT for restaging of biochemical recurrent prostate cancer

Energy Technology Data Exchange (ETDEWEB)

Eiber, Matthias [Klinikum rechts der Isar, Department of Nuclear Medicine, Technische Universitaet Muenchen, Munich (Germany); David Geffen School of Medicine at UCLA, Department of Molecular and Medical Pharmacology, Los Angeles (United States); Rauscher, Isabel; Souvatzoglou, Michael; Schwaiger, Markus [Klinikum rechts der Isar, Department of Nuclear Medicine, Technische Universitaet Muenchen, Munich (Germany); Maurer, Tobias [Klinikum rechts der Isar, Department of Urology, Technische Universitaet Muenchen, Munich (Germany); Holzapfel, Konstantin [Klinikum rechts der Isar, Department of Radiology, Technische Universitaet Muenchen, Munich (Germany); Beer, Ambros J. [Klinikum rechts der Isar, Department of Nuclear Medicine, Technische Universitaet Muenchen, Munich (Germany); Ulm University, Department of Nuclear Medicine, Ulm (Germany)

2017-12-15

Whole-body integrated {sup 11}C-choline PET/MR might provide advantages compared to {sup 11}C-choline PET/CT for restaging of prostate cancer (PC) due to the high soft-tissue contrast and the use of multiparametric MRI, especially for detection of local recurrence and bone metastases. Ninety-four patients with recurrent PC underwent a single-injection/dual-imaging protocol with contrast-enhanced PET/CT followed by fully diagnostic PET/MR. Imaging datasets were read separately by two reader teams (team 1 and 2) assessing the presence of local recurrence, lymph node and bone metastases in predefined regions using a five-point scale. Detection rates were calculated. The diagnostic performance of PET/CT vs. PET/MR was compared using ROC analysis. Inter-observer and inter-modality variability, radiation exposure, and mean imaging time were evaluated. Clinical follow-up, imaging, and/or histopathology served as standard of reference (SOR). Seventy-five patients qualified for the final image analysis. A total of 188 regions were regarded as positive: local recurrence in 37 patients, 87 regions with lymph node metastases, and 64 regions with bone metastases. Mean detection rate between both readers teams for PET/MR was 84.7% compared to 77.3% for PET/CT (p > 0.05). Local recurrence was identified significantly more often in PET/MR compared to PET/CT by team 1. Lymph node and bone metastases were identified significantly more often in PET/CT compared to PET/MR by both teams. However, this difference was not present in the subgroup of patients with PSA values ≤2 ng/ml. Inter-modality and inter-observer agreement (K > 0.6) was moderate to substantial for nearly all categories. Mean reduction of radiation exposure for PET/MR compared to PET/CT was 79.7% (range, 72.6-86.2%). Mean imaging time for PET/CT was substantially lower (18.4 ± 0.7 min) compared to PET/MR (50.4 ± 7.9 min). {sup 11}C-choline PET/MR is a robust imaging modality for restaging biochemical recurrent PC

Lewis acidic (choline chloride.3ZnCl2) ionic liquid: A green and ...

Indian Academy of Sciences (India)

Choline chloride; zinc chloride; ionic liquid; one-pot; triarylmethane. 1. Introduction ... applications such as zinc electroplating11 and batter- ies.12 It has also been used as ... as indicated by Thin Layer Chromatography (TLC), the catalyst was ...

Adenosine diphosphate sugar pyrophosphatase prevents glycogen biosynthesis in Escherichia coli

Science.gov (United States)

Moreno-Bruna, Beatriz; Baroja-Fernández, Edurne; Muñoz, Francisco José; Bastarrica-Berasategui, Ainara; Zandueta-Criado, Aitor; Rodríguez-López, Milagros; Lasa, Iñigo; Akazawa, Takashi; Pozueta-Romero, Javier

2001-01-01

An adenosine diphosphate sugar pyrophosphatase (ASPPase, EC 3.6.1.21) has been characterized by using Escherichia coli. This enzyme, whose activities in the cell are inversely correlated with the intracellular glycogen content and the glucose concentration in the culture medium, hydrolyzes ADP-glucose, the precursor molecule of glycogen biosynthesis. ASPPase was purified to apparent homogeneity (over 3,000-fold), and sequence analyses revealed that it is a member of the ubiquitously distributed group of nucleotide pyrophosphatases designated as “nudix” hydrolases. Insertional mutagenesis experiments leading to the inactivation of the ASPPase encoding gene, aspP, produced cells with marginally low enzymatic activities and higher glycogen content than wild-type bacteria. aspP was cloned into an expression vector and introduced into E. coli. Transformed cells were shown to contain a dramatically reduced amount of glycogen, as compared with the untransformed bacteria. No pleiotropic changes in the bacterial growth occurred in both the aspP-overexpressing and aspP-deficient strains. The overall results pinpoint the reaction catalyzed by ASPPase as a potential step of regulating glycogen biosynthesis in E. coli. PMID:11416161

Folate, vitamin B12, alpha-tocopherol and selected liver components in periparturient dairy goats supplemented with choline and vitamin E

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V. Dell'Orto

2010-04-01

Full Text Available The influence of rumen-protected choline and vitamin E administration on status of folate, vitamin B12, and vitamin E and selected liver components was studied on 4 groups of 12 periparturient dairy goats: control, CTR; choline supplemented, RPC; vitamin E, VITE; choline and vitamin E, RPCE. Plasma folate did not differ between groups, except at parturition when RPC and RPCE goats had higher folate levels than CTR and VITE animals. Neither RPC nor vitamin E affected vitamin B12 plasma concentrations, while a time effect was observed after the third week of lactation, when B12 levels in each group started to increase. Alpha-tocopherol supplementation was associated with increased plasma a-tocopherol in the VITE and RPCE compared to the CRT and RPC groups, while RPC supplementation did not affect a-tocopherol levels in both RPC and RPCE groups compared to CTR and VITE ones. In control and RPC goats liver total lipid did not differ, while DNA contents and their ratio, were respectively higher and lower in RPC supplemented animals. Overall these results suggest that greater choline availability seems to be essential for optimising metabolic health and methyl group status, in dairy ruminants.

Acquisition of wild-type HIV-1 infection in a patient on pre-exposure prophylaxis with high intracellular concentrations of tenofovir diphosphate: a case report.

NARCIS (Netherlands)

Hoornenborg, Elske; Prins, Maria; Achterbergh, Roel C A; Woittiez, Lycke R; Cornelissen, Marion; Jurriaans, Suzanne; Kootstra, Neeltje A; Anderson, Peter L; Reiss, Peter; de Vries, Henry J C; Prins, Jan M; de Bree, Godelieve J

2017-01-01

Pre-exposure prophylaxis (PrEP) with emtricitabine and tenofovir disoproxil fumarate is highly effective against acquisition of HIV infection, and only two cases of infection with a multidrug-resistant virus have been reported under adequate long-term adherence, as evidenced by tenofovir diphosphate

Effect of hypoxia on the uptake of [methyl-3H]choline, [1-14C] acetate and [18F]FDG in cultured prostate cancer cells

International Nuclear Information System (INIS)

Hara, Toshihiko; Bansal, Aditya; DeGrado, Timothy R.

2006-01-01

Introduction: Choline, acetate and glucose ([2- 18 F]fluoro-2-deoxyglucose, [ 18 F]FDG) analogs are under investigation as positron emission tomography (PET) tracers for the imaging of prostate cancer; however, their response to tumor hypoxia has not been clarified. Methods: The uptake of [methyl- 3 H]choline, [1- 14 C]acetate and [ 18 F]FDG was monitored in androgen-independent PC-3 cells and androgen-sensitive LNCaP cells under aerobic or anoxic conditions. The effect of androgen depletion was also examined. Results: PC-3 cells exhibited aerobic choline and acetate uptake five to six times higher than FDG uptake, whereas LNCaP cells showed choline uptake 2.2-fold higher than acetate uptake and 10-fold higher than FDG uptake. After 4 h of anoxia, PC-3 cells showed an 85% increase in FDG uptake, a 15% decrease in choline uptake and a 36% increase in acetate uptake, whereas LNCaP cells showed a 212% increase in FDG uptake, a 28% decrease in choline uptake and no change in acetate uptake. Androgen depletion resulted in a marked decrease in the uptake of all tracers in LNCaP cells but no changes in PC-3 cells. Conclusion: In aerobic conditions, both PC-3 and LNCaP cells exhibited an order of uptake preference as follows: choline>acetate>FDG. In hypoxic cells, the order is reversed, reflecting diverse biochemical responses to hypoxia. These findings may help to explain PET imaging findings of the diverse responses of these tracers in different stages and locations of prostate cancer. Androgen depletion markedly suppressed the uptake of all three tracers in LNCaP cells, which suggests the potential for underestimation of the disease state when PET imaging is performed subsequent to antiandrogen therapy

Bornyl-diphosphate synthase from Lavandula angustifolia: A major monoterpene synthase involved in essential oil quality.

Science.gov (United States)

Despinasse, Yolande; Fiorucci, Sébastien; Antonczak, Serge; Moja, Sandrine; Bony, Aurélie; Nicolè, Florence; Baudino, Sylvie; Magnard, Jean-Louis; Jullien, Frédéric

2017-05-01

Lavender essential oils (EOs) of higher quality are produced by a few Lavandula angustifolia cultivars and mainly used in the perfume industry. Undesirable compounds such as camphor and borneol are also synthesized by lavender leading to a depreciated EO. Here, we report the cloning of bornyl diphosphate synthase of lavender (LaBPPS), an enzyme that catalyzes the production of bornyl diphosphate (BPP) and then by-products such as borneol or camphor, from an EST library. Compared to the BPPS of Salvia officinalis, the functional characterization of LaBPPS showed several differences in amino acid sequence, and the distribution of catalyzed products. Molecular modeling of the enzyme's active site suggests that the carbocation intermediates are more stable in LaBPPS than in SoBPPS leading probably to a lower efficiency of LaBPPS to convert GPP into BPP. Quantitative RT-PCR performed from leaves and flowers at different development stages of L. angustifolia samples show a clear correlation between transcript level of LaBPPS and accumulation of borneol/camphor, suggesting that LaBPPS is mainly responsible of in vivo biosynthesis of borneol/camphor in fine lavender. A phylogenetic analysis of terpene synthases (TPS) pointed out the basal position of LaBPPS in the TPSb clade, suggesting that LaBPPS could be an ancestor of others lavender TPSb. Finally, borneol could be one of the first monoterpenes to be synthesized in the Lavandula subgenus. Knowledge gained from these experiments will facilitate future studies to improve the lavender oils through metabolic engineering or plant breeding. Accession numbers: LaBPPS: KM015221. Copyright © 2017. Published by Elsevier Ltd.

Effect of fructose diphosphate combined with large-dose vitamin C therapy on the myocardial oxidative stress injury after neonatal asphyxia

Directory of Open Access Journals (Sweden)

Chun-Hua Liang1

2017-04-01

Full Text Available Objective: To study the effect of fructose diphosphate combined with large-dose vitamin C therapy on the myocardial oxidative stress injury after neonatal asphyxia. Methods: 40 patients with neonatal asphyxia who were treated in our hospital between June 2013 and April 2016 were collected and divided into the control group (n=20 who received large-dose vitamin C therapy and the observation group (n=20 who received fructose diphosphate combined with large-dose vitamin C therapy according to the double-blind randomized control method, and the treatment lasted for 10 d. Immediately after admission and after 10 d of treatment, RIA method was used to detect the serum levels of oxidative stress indexes, color Doppler diasonograph was used to determine left cardiac function parameters, and the myocardial enzyme spectrum detector was used to determine myocardial enzyme spectrum index levels. Results: Immediately after admission, the differences in the systemic oxidative stress degree, the left cardiac function damage degree and the myocardial enzyme spectrum index levels were not statistically significant between two groups of patients (P>0.05. After 10 d of treatment, serum malondialdehyde (MDA, advanced oxidation protein products (AOPP, creatine kinase isoenzyme (CK-MB, N-terminal pro-brain natriuretic peptide (Nt-proBNP, heart-type fatty acid-binding protein (H-FABP and troponin I (cTnI contents of observation group were lower than those of control group (P<0.05 while superoxide dismutase (SOD content was higher than that of control group (P<0.05, and the left cardiac function parameter ejection time (ET level was higher than that of control group (P<0.05 while left ventricular isovolumetric contraction time (ICT and left ventricular isovolumetric relaxation time (IRT levels were lower than those of control group (P<0.05. Conclusion: Fructose diphosphate combined with large-dose vitamin C can reduce the systemic oxidative stress of neonatal asphyxia

68Ga-PSMA and 11C-Choline comparison using a tri-modality PET/CT-MRI (3.0 T) system with a dedicated shuttle.

Science.gov (United States)

Alonso, Omar; Dos Santos, Gerardo; García Fontes, Margarita; Balter, Henia; Engler, Henry

2018-01-01

The aim of this study was to prospectively compare the detection rate of 68 Ga-PSMA versus 11 C-Choline in men with prostate cancer with biochemical recurrence and to demonstrate the added value of a tri-modality PET/CT-MRI system. We analysed 36 patients who underwent both 11 C-Choline PET/CT and 68 Ga-PSMA PET/CT scanning within a time window of 1-2 weeks. Additionally, for the 68 Ga-PSMA scan, we used a PET/CT-MRI (3.0 T) system with a dedicated shuttle, acquiring MRI images of the pelvis. Both scans were positive in 18 patients (50%) and negative in 8 patients (22%). Nine patients were positive with 68 Ga-PSMA alone (25%) and one with 11 C-Choline only (3%). The median detected lesion per patient was 2 for 68 Ga-PSMA (range 0-93) and 1 for 11 C-Choline (range 0-57). Tumour to background ratios in all concordant lesions ( n  = 96) were higher for 68 Ga-PSMA than for 11 C-Choline (110.3 ± 107.8 and 27.5 ± 17.1, mean ± S.D., for each tracer, respectively P  = 0.0001). The number of detected lesions per patient was higher for 11 C-Choline in those with PSA ≥ 3.3 ng/mL, while the number of detected lesions was independent of PSA levels for 68 Ga-PSMA using the same PSA cut-off value. Metastatic pelvic lesions were found in 25 patients (69%) with 68 Ga-PSMA PET/CT, in 18 (50%) with 11 C-Choline PET/CT and in 21 (58%) with MRI (3.0 T). MRI was very useful in detecting recurrence in cases classified as indeterminate by means of PET/CT alone at prostate bed. In patients with prostate cancer with biochemical recurrence 68 Ga-PSMA detected more lesions per patient than 11 C-Choline, regardless of PSA levels. PET/CT-MRI (3.0 T) system is a feasible imaging modality that potentially adds useful relevant information with increased accuracy of diagnosis.

A 24-hour dietary recall for assessing the intake pattern of choline among Bangladeshi pregnant women at their third trimester of pregnancy

Directory of Open Access Journals (Sweden)

Shatabdi Goon

2014-04-01

Full Text Available Maternal choline intake during the third trimester of human pregnancy can modify systemic and local epigenetic marks in fetal-derived tissues, promoting better pregnancy outcomes, increased immunity, as well as improved mental and physical work capacity with proper memory and cognitive development. 103 pregnant women presenting to the antenatal care of Azimpur Maternity Hospital of Dhaka, Bangladesh in their third trimester of pregnancy were randomly selected for this cross sectional study exploring dietary intake patterns of choline. A dietary recall form was administered to estimate frequency and amount of food consumption of foods for the previous 24 hours. Most women reported diets that delivered less than the recommended choline intake (mean ± SD; 189.5 ± 98.2 providing only 42.72% of total RDA value. The results of this study may indicate that dietary choline among pregnant, Bangladeshi women may not be adequate to meet the needs of both, the mother and fetus. Further studies are warranted to determine clinical implications. Normal 0 false false false MicrosoftInternetExplorer4

Crotoxin, the major toxin from the rattlesnake Crotalus durissus terrificus, inhibits ³H-choline uptake in guinea pig ileum

Directory of Open Access Journals (Sweden)

L.S. Kattah

2000-09-01

Full Text Available We examined the effect of crotoxin, the neurotoxic complex from the venom of the South American rattlesnake Crotalus durissus terrificus, on the uptake of ³H-choline in minces of smooth muscle myenteric plexus from guinea pig ileum. In the concentration range used (0.03-1 µM and up to 10 min of treatment, crotoxin decreased ³H-choline uptake by 50-75% compared to control. This inhibition was time dependent and did not seem to be associated with the disruption of the neuronal membrane, because at least for the first 20 min of tissue exposure to the toxin (up to 1 µM the levels of lactate dehydrogenase (LDH released into the supernatant were similar to those of controls. Higher concentrations of crotoxin or more extensive incubation times with this toxin resulted in elevation of LDH activity detected in the assay supernatant. The inhibitory effect of crotoxin on ³H-choline uptake seems to be associated with its phospholipase activity since the equimolar substitution of Sr2+ for Ca2+ in the incubation medium or the modification of the toxin with p-bromophenacyl bromide substantially decreased this effect. Our results show that crotoxin inhibits ³H-choline uptake with high affinity (EC25 = 10 ± 5 nM. We suggest that this inhibition could explain, at least in part, the blocking effect of crotoxin on neurotransmission.

Electron density reactivity indexes of the tautomeric/ionization forms of thiamin diphosphate.

Science.gov (United States)

Jaña, Gonzalo A; Delgado, Eduardo J

2013-09-01

The generation of the highly reactive ylide in thiamin diphosphate catalysis is analyzed in terms of the nucleophilicity of key atoms, by means of density functional calculations at X3LYP/6-31++G(d,p) level of theory. The Fukui functions of all tautomeric/ionization forms are calculated in order to assess their reactivity. The results allow to conclude that the highly conserved glutamic residue does not protonate the N1' atom of the pyrimidyl ring, but it participates in a strong hydrogen bonding, stabilizing the eventual negative charge on the nitrogen, in all forms involved in the ylide generation. This condition provides the necessary reactivity on key atoms, N4' and C2, to carry out the formation of the ylide required to initiate the catalytic cycle of ThDP-dependent enzymes. This study represents a new approach for the ylide formation in ThDP catalysis.

Asymmetric Stetter reactions catalyzed by thiamine diphosphate-dependent enzymes.

Science.gov (United States)

Kasparyan, Elena; Richter, Michael; Dresen, Carola; Walter, Lydia S; Fuchs, Georg; Leeper, Finian J; Wacker, Tobias; Andrade, Susana L A; Kolter, Geraldine; Pohl, Martina; Müller, Michael

2014-12-01

The intermolecular asymmetric Stetter reaction is an almost unexplored transformation for biocatalysts. Previously reported thiamine diphosphate (ThDP)-dependent PigD from Serratia marcescens is the first enzyme identified to catalyze the Stetter reaction of α,β-unsaturated ketones (Michael acceptor substrates) and α-keto acids. PigD is involved in the biosynthesis of the potent cytotoxic agent prodigiosin. Here, we describe the investigation of two new ThDP-dependent enzymes, SeAAS from Saccharopolyspora erythraea and HapD from Hahella chejuensis. Both show a high degree of homology to the amino acid sequence of PigD (39 and 51 %, respectively). The new enzymes were heterologously overproduced in Escherichia coli, and the yield of soluble protein was enhanced by co-expression of the chaperone genes groEL/ES. SeAAS and HapD catalyze intermolecular Stetter reactions in vitro with high enantioselectivity. The enzymes possess a characteristic substrate range with respect to Michael acceptor substrates. This provides support for a new type of ThDP-dependent enzymatic activity, which is abundant in various species and not restricted to prodigiosin biosynthesis in different strains. Moreover, PigD, SeAAS, and HapD are also able to catalyze asymmetric carbon-carbon bond formation reactions of aldehydes and α-keto acids, resulting in 2-hydroxy ketones.

[A machine learning model using gut microbiome data for predicting changes of trimethylamine-N-oxide in healthy volunteers after choline consumption].

Science.gov (United States)

Lu, Jun-Qi; Wang, Shan; Yin, Jia; Wu, Shan; He, Yan; Zheng, Hui-Min; Sheng, Hua-Fang; Zhou, Hong-Wei

2017-03-20

To establish a machine learning model based on gut microbiota for predicting the level of trimethylamine N-oxide (TMAO) metabolism in vivo after choline intake to provide guidance of individualized precision diet and evidence for screening population at high risks of cardiovascular disease. We quantified plasma levels of TMAO in 18 healthy volunteers before and 8 h after a choline challenge (ingestion of two boiled eggs). The volunteers were divided into two groups with increased or decreased TMAO level following choline challenge. Fresh fecal samples were collected before taking fasting blood samples for amplifying 16S rRNA V4 tags, and the PCR products were sequenced using the platform of Illumina HiSeq 2000. The differences in gut microbiata between subjects with increased and decreased plasma TMAO were analyzed using QIIME. Based on the gut microbiota data and TMAO levels in the two groups, the prediction model was established using the machine learning random forest algorithm, and the validity of the model was tested using a verified dataset. An obvious difference was found in beta diversity of the gut microbota between the subjects with increased and decreased plasma TMAO level following choline challenge. The area under the curve (AUC) of the model was 86.39% (95% CI: 72.7%-100%). Using the verified dataset, the model showed a much higher probability for correctly predicting TMAO variation following choline challenge. The model is feasible and reliable for predicting the level of TMAO metabolism in vivo based on gut microbiota.

A comparison between endogenous acetylcholiner release and (3H) choline outflow from guinea-pig brain slices

International Nuclear Information System (INIS)

Beani, L.; Bianchi, C.; Siniscalchi, A.; Sivilotti, L.; Tanganelli, S.; Veratti, E.

1986-01-01

The measure of tritium-choline efflux from preloaded brain slices is considered a valid method for studying cholinergic functiton. At variance with th say of endogenous acetylcholine this procedure gives andindex of the release process in the absence of esterase inhibition, thus excluding the dampening of the autoreceptor-mediated negative feedback. In order to establish the equivalence of these approaches the tow methods have been compared on electrically=stimulated guinea-pig brain slices, kept under the ame experimental conditions. The results show that only a partial equivalence of the two methods can be recognized. A drawback of the tritium-choline approach is the exhaustion or dilution of tritium stores, so that drug-induced increases of evoked efflux are minimized

Inhibition of Coenzyme Qs Accumulation in Engineered Escherichia coli by High Concentration of Farnesyl Diphosphate

Science.gov (United States)

Samoudi, Mojtaba; Omid Yeganeh, Negar; Shahbani Zahiri, Hossein; Shariati, Parvin; Hajhosseini, Reza

2015-01-01

Background: Coenzyme Q 10 (CoQ 10 ) is an isoprenoid component used widely in nutraceutical industries. Farnesyl diphosphate synthase (FPPS) is a responsible enzyme for biosynthesis of farnesyl diphosphate (FPP), a key precursor for CoQs production. This research involved investigating the effect of FPPS over-expression on CoQs production in engineered CoQ 10 -producing Escherichia coli (E. coli). Methods: Two CoQ 10 -producing strains, as referred to E. coli Ba and E. coli Br, were transformed by the encoding gene for FPPS (ispA) under the control of either the trc or P BAD promoters. Results: Over-expression of ispA under the control of P BAD promoter led to a relative increase in CoQ 10 production only in recombinant E. coli Br although induction by arabinose resulted in partial reduction of CoQ 10 production in both recombinant E. coli Ba and E. coli Br strains. Over-expression of ispA under the control of stronger trc promoter, however, led to a severe decrease in CoQ 10 production in both recombinant E. coli Ba and E. coli Br strains, as reflected by reductions from 629±40 to 30±13 and 564±28 to 80±14 μg/g Dried Cell Weight (DCW), respectively. The results showed high level of FPP reduces endogenous CoQ 8 production as well and that CoQs are produced in a complimentary manner, as the increase in production of one decreases the production of the other. Conclusion: The reduction in CoQ 10 production can be a result of Dds inhibition by high FPP concentration. Therefore, more effort is needed to verify the role of intermediate metabolite concentration and to optimize production of CoQ 10 . PMID:26306151

Kinetic study of the thorium phosphate - diphosphate dissolution

International Nuclear Information System (INIS)

Dacheux, N.; Thomas, A.C.; Brandel, V.; Genet, M.

2000-01-01

The thorium phosphate-diphosphate Th 4 (PO 4 ) 4 P 2 O 7 (TPD) structure allows the replacement of large amounts of thorium by tetravalent actinides leading to the formation of solid solutions. This compound was obtained in powdered or sintered form after pressing at room temperature at 300-800 MPa then heating at 1250 deg. C for 10-30 hours. The resistance of this material to aqueous corrosion was determined by varying several parameters such as surface, leaching flow, acidity or temperature. It was thus possible to independently determine the influence of each parameter on the leaching rate provided that the saturation of the solution was not obtained. In acidic media, the partial order related to [H 3 O + ] was found to be in the 0.31-0.35 range while, in basic media, the partial order related to [OH - ] was almost the same (0.45). The activation energy (42 kJ/mol) was determined between 4 deg. C and 120 deg. C. Moreover, the addition of phosphate in the leachate slightly increased the TPD dissolution rate. When the saturation of the solution is reached, a gelatinous precipitate controls the thorium and phosphate concentrations. The complete characterization of this solid led to the proposed general formula Th 2 (PO 4 ) 2 (HPO 4 ). n H 2 O which conventional solubility product (at I = 0 M) is very low: K * S,0 10 -66.6±1.2 even in very acidic media. (authors)

SIMULTANEOUS ANALYSIS OF AZIDOTHYMIDINE AND ITS MONOPHOSPHATE, DIPHOSPHATE AND TRIPHOSPHATE DERIVATIVES IN BIOLOGICAL-FLUIDS, TISSUE AND CULTURED-CELLS BY A RAPID HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHIC METHOD

NARCIS (Netherlands)

MOLEMA, G; JANSEN, RW; Visser, Jan; MEIJER, DKF

1992-01-01

A rapid high-performance liquid chromatographic (HPLC) method for the simultaneous analysis of the antiviral drug azidothymidine (AZT), AZT monophosphate, AZT diphosphate and AZT triphosphate, with ultraviolet detection in the nanomolar range, is described. Determination of these compounds in vitro

Histopathological correlation of 11C-choline PET scans for target volume definition in radical prostate radiotherapy

International Nuclear Information System (INIS)

Chang, Joe H.; Joon, Daryl Lim; Lee, Sze Ting; Gong, Sylvia J.; Scott, Andrew M.; Davis, Ian D.; Clouston, David; Bolton, Damien; Hamilton, Christopher S.; Khoo, Vincent

2011-01-01

Background and purpose: To evaluate the accuracy of 11 C-choline PET scans in defining dominant intraprostatic lesions (DILs) for radiotherapy target volume definition. Material and methods: Eight men with prostate cancer who had 11 C-choline PET scans prior to radical prostatectomy were studied. Several methods were used to contour the DIL on the PET scans: visual, PET Edge, Region Grow, absolute standardised uptake value (SUV) thresholds and percentage of maximum SUV thresholds. Prostatectomy specimens were sliced in the transverse plane and DILs were delineated on these by a pathologist. These were then compared with the PET scans. The accuracy of correlation was assessed by the Dice similarity coefficient (DSC) and the Youden index. Results: The contouring method resulting in both the highest DSC and the highest Youden index was 60% of the maximum SUV (SUV 60% ), with values of 0.64 and 0.51, respectively. However SUV 60% was not statistically significantly better than all of the other methods by either measure. Conclusions: Although not statistically significant, SUV 60% resulted in the best correlation between 11 C-choline PET and pathology amongst all the methods studied. The degree of correlation shown here is consistent with previous studies that have justified using imaging for DIL radiotherapy target volume definition.

The role of positron emission tomography/computed tomography imaging with radiolabeled choline analogues in prostate cancer.

Science.gov (United States)

Navarro-Pelayo Láinez, M M; Rodríguez-Fernández, A; Gómez-Río, M; Vázquez-Alonso, F; Cózar-Olmo, J M; Llamas-Elvira, J M

2014-11-01

prostate cancer is the most frequent solid malignant tumor in Western Countries. Positron emission tomography/x-ray computed tomography imaging with radiolabeled choline analogues is a useful tool for restaging prostate cancer in patients with rising prostate-specific antigen after radical treatment (in whom conventional imaging techniques have important limitations) as well as in the initial assessment of a selected group of prostate cancer patients. For this reason a literature review is necessary in order to evaluate the usefulness of this imaging test for the diagnosis and treatment of prostate cancer. a MEDLINE (PubMed way) literature search was performed using the search parameters: «Prostate cancer» and «Choline-PET/CT». Other search terms were «Biochemical failure» and/or «Staging» and/or «PSA kinetics». English and Spanish papers were selected; original articles, reviews, systematic reviews and clinical guidelines were included. according to available data, radiolabeled choline analogues plays an important role in the management of prostate cancer, especially in biochemical relapse because technique accuracy is properly correlated with prostate-specific antigen values and kinetics. Although is an emerging diagnostic technique useful in treatment planning of prostate cancer, final recommendations have not been submitted. Copyright © 2013 AEU. Published by Elsevier Espana. All rights reserved.

Functional evidence for the critical amino-terminal conserved domain and key amino acids of Arabidopsis 4-HYDROXY-3-METHYLBUT-2-ENYL DIPHOSPHATE REDUCTASE.

Science.gov (United States)

Hsieh, Wei-Yu; Sung, Tzu-Ying; Wang, Hsin-Tzu; Hsieh, Ming-Hsiun

2014-09-01

The plant 4-HYDROXY-3-METHYLBUT-2-ENYL DIPHOSPHATE REDUCTASE (HDR) catalyzes the last step of the methylerythritol phosphate pathway to synthesize isopentenyl diphosphate and its allyl isomer dimethylallyl diphosphate, which are common precursors for the synthesis of plastid isoprenoids. The Arabidopsis (Arabidopsis thaliana) genomic HDR transgene-induced gene-silencing lines are albino, variegated, or pale green, confirming that HDR is essential for plants. We used Escherichia coli isoprenoid synthesis H (Protein Data Bank code 3F7T) as a template for homology modeling to identify key amino acids of Arabidopsis HDR. The predicted model reveals that cysteine (Cys)-122, Cys-213, and Cys-350 are involved in iron-sulfur cluster formation and that histidine (His)-152, His-241, glutamate (Glu)-242, Glu-243, threonine (Thr)-244, Thr-312, serine-379, and asparagine-381 are related to substrate binding or catalysis. Glu-242 and Thr-244 are conserved only in cyanobacteria, green algae, and land plants, whereas the other key amino acids are absolutely conserved from bacteria to plants. We used site-directed mutagenesis and complementation assay to confirm that these amino acids, except His-152 and His-241, were critical for Arabidopsis HDR function. Furthermore, the Arabidopsis HDR contains an extra amino-terminal domain following the transit peptide that is highly conserved from cyanobacteria, and green algae to land plants but not existing in the other bacteria. We demonstrated that the amino-terminal conserved domain was essential for Arabidopsis and cyanobacterial HDR function. Further analysis of conserved amino acids in the amino-terminal conserved domain revealed that the tyrosine-72 residue was critical for Arabidopsis HDR. These results suggest that the structure and reaction mechanism of HDR evolution have become specific for oxygen-evolving photosynthesis organisms and that HDR probably evolved independently in cyanobacteria versus other prokaryotes. © 2014

Acid dissociation constants of uridine-5 Prime -diphosphate compounds determined by {sup 31}phosphorus nuclear magnetic resonance spectroscopy and internal pH referencing

Energy Technology Data Exchange (ETDEWEB)

Jancan, Igor [Louisiana State University, Department of Chemistry, Baton Rouge, LA 70803 (United States); Macnaughtan, Megan A., E-mail: macnau@lsu.edu [Louisiana State University, Department of Chemistry, Baton Rouge, LA 70803 (United States)

2012-10-24

Highlights: Black-Right-Pointing-Pointer The first reported phosphate and imide pK{sub a} values of UDP-GlcNAc and UDP-S-GlcNAc. Black-Right-Pointing-Pointer New role for the monosaccharide in the imide pK{sub a} of uridine-5 Prime -phosphate compounds. Black-Right-Pointing-Pointer UDP-S-GlcNAc and UDP-GlcNAc have the same phosphate pK{sub a}, unlike thioyl analogs. Black-Right-Pointing-Pointer The {sup 31}P chemical shift of inorganic phosphate is a viable internal pH reference. Black-Right-Pointing-Pointer Stability of the external {sup 31}P chemical shift reference is essential. - Abstract: The acid dissociation constant (pK{sub a}) of small, biological molecules is an important physical property used for investigating enzyme mechanisms and inhibitor design. For phosphorus-containing molecules, the {sup 31}P nuclear magnetic resonance (NMR) chemical shift is sensitive to the local chemical environment, particularly to changes in the electronic state of the molecule. Taking advantage of this property, we present a {sup 31}P NMR approach that uses inorganic phosphate buffer as an internal pH reference to determine the pK{sub a} values of the imide and second diphosphate of uridine-5 Prime -diphosphate compounds, including the first reported values for UDP-GlcNAc and UDP-S-GlcNAc. New methods for using inorganic phosphate buffer as an internal pH reference, involving mathematical correction factors and careful control of the chemical shift reference sample, are illustrated. A comparison of the newly determined imide and diphosphate pK{sub a} values of UDP, UDP-GlcNAc, and UDP-S-GlcNAc with other nucleotide phosphate and thio-analogs reveals the significance of the monosaccharide and sulfur position on the pK{sub a} values.

Prospective evaluation of [11C]Choline PET/CT in therapy response assessment of standardized docetaxel first-line chemotherapy in patients with advanced castration refractory prostate cancer

International Nuclear Information System (INIS)

Schwarzenboeck, Sarah M.; Krause, Bernd J.; Eiber, Matthias; Schwaiger, Markus; Kundt, Guenther; Retz, Margitta; Treiber, Uwe; Nawroth, Roman; Gschwend, Juergen E.; Thalgott, Mark; Sakretz, Monique; Kurth, Jens; Rummeny, Ernst J.

2016-01-01

The aim of this study was to prospectively evaluate the value of [ 11 C] Choline PET/CT in monitoring early and late response to a standardized first-line docetaxel chemotherapy in castration refractory prostate cancer (mCRPC) patients. Thirty-two patients were referred for [ 11 C] Choline PET/CT before the start of docetaxel chemotherapy, after one and ten chemotherapy cycles (or - in case of discontinuation - after the last administered cycle) for therapy response assessment. [ 11 C] Choline uptake (SUV max , SUV mean ), CT derived Houndsfield units (HU max , HU mean ), and volume of bone, lung, and nodal metastases and local recurrence were measured semi-automatically at these timepoints. Change in SUV max , SUV mean , HU max , HU mean, and volume was assessed between PET 2 and 1 (early response assessment, ERA) and PET 3 and 1 (late response assessment, LRA) on a patient and lesion basis. Results of PET/CT were compared to clinically used RECIST 1.1 and clinical criteria based therapy response assessment including PSA for defining progressive disease (PD) and non-progressive disease (nPD), respectively. Relationships between changes of SUV max and SUV mean (early and late) and changes of PSA early and PSA late were evaluated. Prognostic value of initial SUV max and SUV mean was assessed. Statistical analyses were performed using SPSS. In the patient-based ERA and LRA there were no statistically significant differences in change of choline uptake, HU, and volume between PD and nPD applying RECIST or clinical response criteria. In the lesion-based ERA, decrease in choline uptake of bone metastases was even higher in PD (applying RECIST criteria), whereas in LRA the decrease was higher in nPD (applying clinical criteria). There were only significant correlations between change in choline uptake and PSA in ERA in PD, in LRA no significant correlations were discovered. Initial SUV max and SUV mean were statistically significantly higher in nPD (applying clinical

Chemical interaction of potassium diphosphate with cadmium nitrate in aqueous solution

International Nuclear Information System (INIS)

Kokhanovskij, V.V.

1993-01-01

Formation of low-soluble compounds in 1.5 mol/l isomolar cross section of K 4 P 2 O 7 -Cd(NO 3 ) 2 -H 2 O system was studied. Liquid phases are studied by the methods of refractometry and pH value measuring, an solid ones - by the methods of chemical and X-ray phase analysis, IR spectroscopy, chromatography and microscopy. Three individual chemical compounds K 2 CdP 2 O 7 x 4H 2 O, K 2 Cd 3 (P 2 O 7 ) 2 x 3H 2 O and Cd 2 P 2 O 7 x 3.5H 2 O and some their mixtures were isolated and investigated. It is shown that doulble diphosphate K 6 Cd(P 2 O 7 ) 2 x 6H 2 O does not precipitate spontanously, but instead of it in wide region of system K 2 CdP 2 O 7 x 4H 2 O crystallizes as elongated acicular crystals or as thin plates of improper form

Open reading frame 176 in the photosynthesis gene cluster of Rhodobacter capsulatus encodes idi, a gene for isopentenyl diphosphate isomerase.

OpenAIRE

Hahn, F M; Baker, J A; Poulter, C D

1996-01-01

Isopentenyl diphosphate (IPP) isomerase catalyzes an essential activation step in the isoprenoid biosynthetic pathway. A database search based on probes from the highly conserved regions in three eukaryotic IPP isomerases revealed substantial similarity with ORF176 in the photosynthesis gene cluster in Rhodobacter capsulatus. The open reading frame was cloned into an Escherichia coli expression vector. The encoded 20-kDa protein, which was purified in two steps by ion exchange and hydrophobic...

Automated synthesis of 11C-carfentanil with 11C-choline module and micro PET imaging

International Nuclear Information System (INIS)

Zhang Jinming; Zhang Xiaojun; Tian Jiahe; Xu Zhihong; Xiang Xiaohui

2011-01-01

A simple modified home-made 11 C-choline module enabled to rapid and efficient synthesis 11 C-carfentanil ( 11 C-CFN) as CNS μ-opioid receptor imaging agent. The synthesis of 11 C-CFN was completed in a yield of 14.8 GBq within 18 min from 11 C-CO 2 on the choline module. The methylation took place from 4-piperidinecarboxylic acid, 4-[(1-oxopropyl) phenylamino]-l-(2-phenylethyl), sodium salt as precursor in DMSO solution. The radio- chemical yields were over 80% (n=55, decay-corrected and based on 11 CH 3 -triflate). The radiochemical purity was over 95% and the specific activities was over 1.4 × 10 14 Bq/g. The biologic activity of 11 C-CFN was confirmed with Micro PET/CT imaging. (authors)

Imaging primary prostate cancer with 11C-Choline PET/CT: relation to tumour stage, Gleason score and biomarkers of biologic aggressiveness

International Nuclear Information System (INIS)

Chen, Ji; Zhao, Yong; Li, Xin; Sun, Peng; Wang, Muwen; Wang, Ridong; Jin, Xunbo

2012-01-01

As a significant overlap of 11C-Choline standardized uptake value (SUV) between prostate cancer and benign prostate hyperplasia (BPH) tissue, controversy exists regarding the clinical value of 11C-Choline PET/CT scan in primary prostate cancer. In this study, the SUVmax of the prostate lesions and the pelvic muscles were measured and their ratios (SUVmax-P/M ratio) were calculated. Then we evaluated whether the tracer 11C-Choline uptake, quantified as SUVmax-P/M ratio, correlated with tumour stage, Gleason score, and expression levels of several biomarkers of aggressiveness. Twenty-six patients with primary prostate cancer underwent 11C-Choline PET/CT. Tumour specimens from these patients were graded histopathologically, and immunnohistochemistry for Ki-67, CD31, androgen receptor (AR), Her-2/neu, Bcl-2, and PTEN were performed. Both SUVmax and SUVmax-P/M ratio showed no significant difference between patients with tumour stage II and III, but significantly elevated in patients with tumour stage IV. SUVmax-P/M ratio was also significantly higher in lesions with Gleason score of 4+3 or higher versus less than or equal to 3+4. SUVmax-P/M ratio was found significantly correlated with expression levels of Ki-67 and CD31. In addition, a higher SUVmax-P/M ratio was demonstrated in Her-2/neu positive subgroup than negative subgroup. At the same time, Gleason score and expression levels of these biomarkers showed no significant association with SUVmax. Using the parameter SUVmax-P/M ratio, 11C-Choline PET/CT may be a valuable non-invasive imaging technology in the diagnosis of primary prostate cancer

Targeting personalized medicine in a non-Hodgkin lymphoma patient with {sup 18F}-FDG and {sup 18F}-choline PET/CT

Energy Technology Data Exchange (ETDEWEB)

Ribeiro, Thalles H.; Filho, Raul S.; Castro, Ana Carolina G.; Paulino Junior, Eduardo; Mamede, Marcelo, E-mail: mamede.mm@gmail.com [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil)

2017-02-15

Early diagnosis and staging of non-Hodgkin lymphoma (NHL) is essential for therapeutic strategy decision. Positron emission tomography/computed tomography (PET/CT) with fluorodeoxyglucose (FDG), a glucose analogue, labeled with fluor-18 ({sup 18F}-FDG) has been used to evaluate staging, therapy response and prognosis in NHL patients. However, in some cases, {sup 18F}-FDG has shown false- -positive uptake due to inflammatory reaction after chemo and/or radiation therapy. In this case report, we present a NHL patient evaluated with {sup 18F}-FDG and {sup 18F}-choline PET/CT scan imaging pre- and post-therapy. {sup 18F}-FDG and {sup 18F}-choline PET/CT were performed for the purpose of tumor staging and have shown intense uptake in infiltrative tissue as well as in the lymph node, but with some mismatching in the tumor. Post-treatment {sup 18F}-FDG and {sup 18F}-choline PET/ CT scans revealed no signs of radiotracer uptake, suggesting complete remission of the tumor. {sup 18F}-choline may be a complimentary tool for staging and assessment of therapeutic response in non-Hodgkin lymphoma, while non-{sup 18F}-FDG tracer can be used for targeted therapy and patient management. (author)

Methyl group balance in brain and liver: role of choline on increased S-adenosyl methionine (SAM) demand by chronic arsenic exposure.

Science.gov (United States)

Ríos, Rosalva; Santoyo, Martha E; Cruz, Daniela; Delgado, Juan Manuel; Zarazúa, Sergio; Jiménez-Capdeville, María E

2012-11-30

Arsenic toxicity has been related to its interference with one carbon metabolism, where a high demand of S-adenosylmethionine (SAM) for arsenic methylation as well as a failure of its regeneration would compromise the availability of methyl groups for diverse cellular functions. Since exposed animals show disturbances of methylated products such as methylated arginines, myelin and axon membranes, this work investigates whether alterations of SAM, choline and phosphatidylcholine (PC) in the brain of arsenic exposed rats are associated with myelin alterations and myelin basic protein (MBP) immunoreactivity. Also these metabolites, morphologic and biochemical markers of methyl group alterations were analyzed in the liver, the main site of arsenic methylation. In adult, life-long arsenic exposed rats through drinking water (3 ppm), no changes of SAM, choline and PC concentrations where found in the brain, but SAM and PC were severely decreased in liver accompanied by a significant increase of choline. These results suggest that choline plays an important role as methyl donor in arsenic exposure, which could underlie hepatic affections observed when arsenic exposure is combined with other environmental factors. Also, important myelin and nerve fiber alterations, accompanied by a 75% decrease of MBP immunoreactivity were not associated with a SAM deficit in the brain. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Overexpression, purification and crystallization of a choline-binding protein CbpI from Streptococcus pneumoniae

International Nuclear Information System (INIS)

Paterson, Neil G.; Riboldi-Tunicliffe, Alan; Mitchell, Timothy J.; Isaacs, Neil W.

2006-01-01

The choline-binding protein CbpI from S. pneumoniae has been purified and crystallized and diffraction data have been collected to 3.5 Å resolution. The choline-binding protein CbpI from Streptococcus pneumoniae is a 23.4 kDa protein with no known function. The protein has been successfully purified initially using Ni–NTA chromatography and to homogeneity using Q-Sepharose ion-exchange resin as an affinity column. CbpI was crystallized using PEG 3350 as a precipitant and X-ray crystallographic analysis showed that the crystals belonged to the tetragonal space group P4, with unit-cell parameters a = b = 83.31, c = 80.29 Å, α = β = γ = 90°. The crystal contains two molecules in the asymmetric unit with a solvent content of 55.7% (V M = 2.77 Å 3 Da −1 ) and shows a diffraction limit of 3.5 Å

Overexpression, purification and crystallization of a choline-binding protein CbpI from Streptococcus pneumoniae

Energy Technology Data Exchange (ETDEWEB)

Paterson, Neil G., E-mail: neison@chem.gla.ac.uk; Riboldi-Tunicliffe, Alan [Department of Chemistry and WestCHEM, Glasgow Biomedical Research Centre (GBRC), University of Glasgow, 120 University Place, Glasgow G12 8TA,Scotland (United Kingdom); Mitchell, Timothy J. [Division of Infection and Immunity (IBLS), Glasgow Biomedical Research Centre (GBRC), University of Glasgow, 120 University Place, Glasgow G12 8TA,Scotland (United Kingdom); Isaacs, Neil W. [Department of Chemistry and WestCHEM, Glasgow Biomedical Research Centre (GBRC), University of Glasgow, 120 University Place, Glasgow G12 8TA,Scotland (United Kingdom)

2006-07-01

The choline-binding protein CbpI from S. pneumoniae has been purified and crystallized and diffraction data have been collected to 3.5 Å resolution. The choline-binding protein CbpI from Streptococcus pneumoniae is a 23.4 kDa protein with no known function. The protein has been successfully purified initially using Ni–NTA chromatography and to homogeneity using Q-Sepharose ion-exchange resin as an affinity column. CbpI was crystallized using PEG 3350 as a precipitant and X-ray crystallographic analysis showed that the crystals belonged to the tetragonal space group P4, with unit-cell parameters a = b = 83.31, c = 80.29 Å, α = β = γ = 90°. The crystal contains two molecules in the asymmetric unit with a solvent content of 55.7% (V{sub M} = 2.77 Å{sup 3} Da{sup −1}) and shows a diffraction limit of 3.5 Å.

Acetylcholine and choline contents of rat skeletal muscle determined by a radioenzymatic microassay: effects of drugs

International Nuclear Information System (INIS)

Consolo, S.

1986-01-01

This paper describes a specific, radioenzymatic microassay for measuring picomole quantities of ACh in skeletal muscle. The levels of ACh as well ascholine in the extensor digitorum longus (EDL), soleus and gastrocnemiusmuscles of the rat are reported after focussed microwave irradiation to the hind limb to prevent post-mortem changes in ACh and choline contents. Particular attention was directed to the effect of some drugs potently affecting neuromuscular transmission at the end plate. Preparation of tissue samples, extraction and electrophoresis are described. A 26 ul portion of a second incubation mixture of tritium-acetylcoenzyme A and 14 ul of a partially purified choline acetyltransferase solution were added. A flow sheet giving an overview of he analytical steps involved in the method are shown

{sup 11}C-Choline PET/CT for restaging prostate cancer. Results from 4,426 scans in a single-centre patient series

Energy Technology Data Exchange (ETDEWEB)

Graziani, Tiziano; Ceci, Francesco; Polverari, Giulia; Lima, Giacomo Maria; Lodi, Filippo; Fanti, Stefano [S. Orsola-Malpighi Hospital, University of Bologna, Service of Nuclear Medicine, Bologna (Italy); Castellucci, Paolo [S. Orsola-Malpighi Hospital, University of Bologna, Service of Nuclear Medicine, Bologna (Italy); Azienda Ospedaliero-Universitaria di Bologna, Policlinico S. Orsola-Malpighi, UO Medicina Nucleare, Bologna (Italy); Morganti, Alessio Giuseppe [S. Orsola-Malpighi Hospital, University of Bologna, Department of Radiotherapy, Bologna (Italy); Ardizzoni, Andrea [S. Orsola-Malpighi Hospital, University of Bologna, Department of Oncology, Bologna (Italy); Schiavina, Riccardo [S. Orsola-Malpighi Hospital, University of Bologna, Department of Urology, Bologna (Italy)

2016-10-15

To evaluate {sup 11}C-choline PET/CT as a diagnostic tool for restaging prostate cancer (PCa), in a large, homogeneous and clinically relevant population of patients with biochemical recurrence (BCR) of PCa after primary therapy. The secondary aim was to assess the best timing for performing {sup 11}C-choline PET/CT during BCR. We retrospectively analysed 9,632 {sup 11}C-choline PET/CT scans performed in our institution for restaging PCa from January 2007 to June 2015. The inclusion criteria were: (1) proven PCa radically treated with radical prostatectomy (RP) or with primary external beam radiotherapy (EBRT); (2) PSA serum values available; (3) proven BCR (PSA >0.2 ng/mL after RP or PSA >2 ng/mL above the nadir after primary EBRT with rising PSA levels). Finally, 3,203 patients with recurrent PCa matching all the inclusion criteria were retrospectively enrolled and 4,426 scans were analysed. Overall, 52.8 % of the {sup 11}C-choline PET/CT scans (2,337/4,426) and 54.8 % of the patients (1,755/3,203) were positive. In 29.4 % of the scans, at least one distant finding was observed. The mean and median PSA values were, respectively, 4.9 and 2.1 ng/mL at the time of the scan (range 0.2 - 50 ng/mL). In our series, 995 scans were performed in patients with PSA levels between 1 and 2 ng/mL. In this subpopulation the positivity rate in the 995 scans was 44.7 %, with an incidence of distant findings of 19.2 % and an incidence of oligometastatic disease (one to three lesions) of 37.7 %. The absolute PSA value at the time of the scan and ongoing androgen deprivation therapy were associated with an increased probability of a positive {sup 11}C-choline PET/CT scan (p < 0.0001). In the ROC analysis, a PSA value of 1.16 ng/mL was the optimal cut-off value. In patients with a PSA value <1.16 ng/mL, 26.8 % of 1,426 {sup 11}C-choline PET/CT scans were positive, with oligometastatic disease in 84.7 % of positive scans. In a large cohort of patients, the feasibility of {sup 11}C-choline

Prospective evaluation of [{sup 11}C]Choline PET/CT in therapy response assessment of standardized docetaxel first-line chemotherapy in patients with advanced castration refractory prostate cancer

Energy Technology Data Exchange (ETDEWEB)

Schwarzenboeck, Sarah M.; Krause, Bernd J. [Technical University of Munich, Department of Nuclear Medicine, Klinikum rechts der Isar, Munich (Germany); Rostock University Medical Centre, Department of Nuclear Medicine, Rostock (Germany); Eiber, Matthias; Schwaiger, Markus [Technical University of Munich, Department of Nuclear Medicine, Klinikum rechts der Isar, Munich (Germany); Kundt, Guenther [Rostock University Medical Centre, Department of Biostatistics and Informatics, Rostock (Germany); Retz, Margitta; Treiber, Uwe; Nawroth, Roman; Gschwend, Juergen E.; Thalgott, Mark [Technical University of Munich, Department of Urology, Klinikum rechts der Isar, Munich (Germany); Sakretz, Monique; Kurth, Jens [Rostock University Medical Centre, Department of Nuclear Medicine, Rostock (Germany); Rummeny, Ernst J. [Technical University of Munich, Institute of Radiology, Klinikum rechts der Isar, Munich (Germany)

2016-11-15

The aim of this study was to prospectively evaluate the value of [{sup 11}C] Choline PET/CT in monitoring early and late response to a standardized first-line docetaxel chemotherapy in castration refractory prostate cancer (mCRPC) patients. Thirty-two patients were referred for [{sup 11}C] Choline PET/CT before the start of docetaxel chemotherapy, after one and ten chemotherapy cycles (or - in case of discontinuation - after the last administered cycle) for therapy response assessment. [{sup 11}C] Choline uptake (SUV{sub max}, SUV{sub mean}), CT derived Houndsfield units (HU{sub max}, HU{sub mean}), and volume of bone, lung, and nodal metastases and local recurrence were measured semi-automatically at these timepoints. Change in SUV{sub max}, SUV{sub mean}, HU{sub max}, HU{sub mean,} and volume was assessed between PET 2 and 1 (early response assessment, ERA) and PET 3 and 1 (late response assessment, LRA) on a patient and lesion basis. Results of PET/CT were compared to clinically used RECIST 1.1 and clinical criteria based therapy response assessment including PSA for defining progressive disease (PD) and non-progressive disease (nPD), respectively. Relationships between changes of SUV{sub max} and SUV{sub mean} (early and late) and changes of PSA{sub early} and PSA{sub late} were evaluated. Prognostic value of initial SUV{sub max} and SUV{sub mean} was assessed. Statistical analyses were performed using SPSS. In the patient-based ERA and LRA there were no statistically significant differences in change of choline uptake, HU, and volume between PD and nPD applying RECIST or clinical response criteria. In the lesion-based ERA, decrease in choline uptake of bone metastases was even higher in PD (applying RECIST criteria), whereas in LRA the decrease was higher in nPD (applying clinical criteria). There were only significant correlations between change in choline uptake and PSA in ERA in PD, in LRA no significant correlations were discovered. Initial SUV{sub max

Different behaviors of single and multi wall carbon nanotubes for studying electrochemistry and electrocatalysis of choline oxidase

International Nuclear Information System (INIS)

Sajjadi, Sharareh; Ghourchian, Hedayatollah; Rahimi, Parvaneh

2011-01-01

Highlights: → In the presence of a typical room temperature ionic liquid (RTIL), Choline oxidase (ChOx) as a model enzyme was uniformly immobilized on either single or multi wall carbon nanotubes (SWCNTs or MWCNTs) covered on glassy carbon (GC) electrode, and the electron transfer and electroanalytical response of enzyme toward choline was evaluated. → ChOx on RTIL/MWCNTs/GC electrode showed higher electrical conductivity, better reversibility of redox reaction and higher electron transfer rate indicating more facile and rapid rate of electron transfer. → On the other hand, RTIL/SWCNTs/GC electrode showed higher amount of enzyme loading, higher enzyme-substrate affinity, lower detection limit, better sensitivity and wider linear range. → Consequently, MWCNTs are preferable for kinetic study of ChOx, while SWCNTs are more convenient for biosensing applications. - Abstract: This work presents a detailed comparison between single and multi wall carbon nanotubes (SWCNTs and MWCNTs) in an effort to understand which could be a better supporting material for studying the electrochemistry and electrocatalysis of enzymes. Choline oxidase (ChOx) was chosen as a model enzyme for evaluation of the electrodes' performance. The enzyme was adsorbed on either SWCNT or MWCNT modified electrode, in the presence of a typical room temperature ionic liquid (RTIL), and its electron transfer and electroanalytical response toward choline was investigated. RTIL/MWCNTs/GC electrode was uniformly covered by ChOx. Besides, higher electrical conductivity, better reversibility of the ChOx redox reaction and higher electron transfer rate of the enzyme indicated more facile and rapid rate of electron transfer. On the other hand, RTIL/SWCNTs/GC electrodes showed higher amount of enzyme loading, higher enzyme-substrate affinity, lower detection limit, better sensitivity and wider linear range. Consequently, MWCNTs are preferable for kinetic study of ChOx, while SWCNTs are more convenient

Choline-amino acid ionic liquids: past and recent achievements about the structure and properties of these really "green" chemicals.

Science.gov (United States)

Gontrani, Lorenzo

2018-06-01

The structure of choline-amino acid ionic liquids, atoxic task-specific solvents composed of materials originated from renewable feedstocks, is reviewed in this letter. The varied and strong interactions that these liquids are capable of establishing are largely dependent on their structure and confer them outstanding solvating properties with respect to a large number of different solutes. Among the experimental methods capable of yielding structural insight, the energy-dispersive version of X-Ray diffraction, that uses the Bremsstrahlung radiation of the X-Ray tube, is a technique very well suited to investigate these liquid systems. The diffraction spectra of five choline-amino acid ionic liquids, recently measured, are reported and discussed; in particular, the presence or absence of the medium-range order pre-peak is related to the presence of polar groups within the amino acid side chain that destroys the hydrophobic interactions between aliphatic chains. In the final section, a recent example of choline-amino acid ionic liquids as for ancient paper preservation and two other interesting results are discussed at the end.

Escherichia coli O157:H7 Converts Plant-Derived Choline to Glycine Betaine for Osmoprotection during Pre- and Post-harvest Colonization of Injured Lettuce Leaves

Directory of Open Access Journals (Sweden)

Russell A. Scott

2017-12-01

Full Text Available Plant injury is inherent to the production and processing of fruit and vegetables. The opportunistic colonization of damaged plant tissue by human enteric pathogens may contribute to the occurrence of outbreaks of foodborne illness linked to produce. Escherichia coli O157:H7 (EcO157 responds to physicochemical stresses in cut lettuce and lettuce lysates by upregulation of several stress response pathways. We investigated the tolerance of EcO157 to osmotic stress imposed by the leakage of osmolytes from injured lettuce leaf tissue. LC-MS analysis of bacterial osmoprotectants in lettuce leaf lysates and wound washes indicated an abundant natural pool of choline, but sparse quantities of glycine betaine and proline. Glycine betaine was a more effective osmoprotectant than choline in EcO157 under osmotic stress conditions in vitro. An EcO157 mutant with a deletion of the betTIBA genes, which are required for biosynthesis of glycine betaine from imported choline, achieved population sizes twofold lower than those of the parental strain (P < 0.05 over the first hour of colonization of cut lettuce in modified atmosphere packaging (MAP. The cell concentrations of the betTIBA mutant also were 12-fold lower than those of the parental strain (P < 0.01 when grown in hypertonic lettuce lysate, indicating that lettuce leaf cellular contents provide choline for osmoprotection of EcO157. To demonstrate the utilization of available choline by EcO157 for osmoadaptation in injured leaf tissue, deuterated (D-9 choline was introduced to wound sites in MAP lettuce; LC-MS analysis revealed the conversion of D9-choline to D-9 glycine betaine in the parental strain, but no significant amounts were observed in the betTIBA mutant. The EcO157 ΔbetTIBA-ΔotsBA double mutant, which is additionally deficient in de novo synthesis of the compatible solute trehalose, was significantly less fit than the parental strain after their co-inoculation onto injured lettuce leaves and

Flow injection determination of choline in milk hydrolysates by an immobilized enzyme reactor coupled to a selective hydrogen peroxide amperometric sensor

Energy Technology Data Exchange (ETDEWEB)

Pati, Sandra [Dipartimento di Chimica, Universita degli Studi di Bari, Via Orabona 4, 70126 Bari (Italy); Quinto, Maurizio [Dipartimento di Scienze Agroambientali, Chimica e Difesa Vegetale, Universita degli Studi di Foggia, Via Napoli 25, 71100 Foggia (Italy); Palmisano, Francesco [Dipartimento di Chimica, Universita degli Studi di Bari, Via Orabona 4, 70126 Bari (Italy)]. E-mail: palmisano@chimica.uniba.it

2007-07-02

A choline oxidase (ChO) immobilized enzyme reactor (IMER) prepared by glutaraldehyde coupling of the enzyme on aminopropyl modified controlled pore glass beads is described. The ChO-IMER was coupled, in a flow injection configuration system, to an interference free hydrogen peroxide amperometric sensor based on a Pt surface modified by an overoxidized polypyrrole film. The resulting analytical device responds selectively to choline and displays a sensitivity of 46.9 {+-} 0.2 {mu}C mM{sup -1} and a limit of detection, calculated at a signal-to-noise ratio equal to 3, of 7 {mu}M. Sensitivity remains constant for about 20 days and then starts to slowly deteriorate and after 2 months a 70% of the initial sensitivity was still retained. The application to choline determination in milk hydrolysates is demonstrated. Short- and long-term drift observed in the analytical response can be corrected by a bracketing technique.

Kinetic study of the thorium phosphate - diphosphate dissolution

Energy Technology Data Exchange (ETDEWEB)

Dacheux, N.; Thomas, A.C.; Brandel, V.; Genet, M. [Paris-11 Univ., 91 - Orsay (France). Inst. de Physique Nucleaire; Aupiais, J. [CEA/DAM-Ile de France, Dept. Analyse Surveillance Environnement, DASE, Service Radioanalyses Chimie Environnement, 91 - Bruyeres-Le-Chatel (France)

2000-07-01

The thorium phosphate-diphosphate Th{sub 4}(PO{sub 4}){sub 4}P{sub 2}O{sub 7} (TPD) structure allows the replacement of large amounts of thorium by tetravalent actinides leading to the formation of solid solutions. This compound was obtained in powdered or sintered form after pressing at room temperature at 300-800 MPa then heating at 1250 deg. C for 10-30 hours. The resistance of this material to aqueous corrosion was determined by varying several parameters such as surface, leaching flow, acidity or temperature. It was thus possible to independently determine the influence of each parameter on the leaching rate provided that the saturation of the solution was not obtained. In acidic media, the partial order related to [H{sub 3}O{sup +}] was found to be in the 0.31-0.35 range while, in basic media, the partial order related to [OH{sup -}] was almost the same (0.45). The activation energy (42 kJ/mol) was determined between 4 deg. C and 120 deg. C. Moreover, the addition of phosphate in the leachate slightly increased the TPD dissolution rate. When the saturation of the solution is reached, a gelatinous precipitate controls the thorium and phosphate concentrations. The complete characterization of this solid led to the proposed general formula Th{sub 2}(PO{sub 4}){sub 2}(HPO{sub 4}). n H{sub 2}O which conventional solubility product (at I = 0 M) is very low: K{sup *}{sub S,0} 10{sup -66.6{+-}}{sup 1.2} even in very acidic media. (authors)

Diagnostic performance of 11C-choline PET/CT and bone scintigraphy in the detection of bone metastases in patients with prostate cancer.

Science.gov (United States)

Kitajima, Kazuhiro; Fukushima, Kazuhito; Yamamoto, Shingo; Kato, Takashi; Odawara, Soichi; Takaki, Haruyuki; Fujiwara, Masayuki; Yamakado, Koichiro; Nakanishi, Yukako; Kanematsu, Akihiro; Nojima, Michio; Hirota, Shozo

2017-08-01

The aim of this study was to compare 11C-choline PET/CT and bone scintigraphy (BS) for detection of bone metastases in patients with prostate cancer. Twenty-one patients with histologically proven prostate cancer underwent 11C-choline PET/CT and BS before (n = 4) or after (n = 17) treatment. Patient-, region-, and lesion-based diagnostic performances of bone metastasis of both 11C-choline PET/CT and BS were evaluated using a five-point scale by two experienced readers. Bone metastases were present in 11 (52.4%) of 21 patients and 48 (32.7%) of 147 regions; 111 lesions were found to have bone metastases. Region-based analysis showed that the sensitivity, specificity, accuracy, and area under the receiver-operating-characteristic curves (AUC) of 11C-choline PET/CT were 97.9%, 99.0%, 98.6%, and 0.9989, respectively; those of BS were 72.9%, 99.0%, 90.5%, and 0.8386, respectively. Sensitivity, accuracy, and AUC significantly differed between the two methods (McNemar test, p = 0.0015, p = 0.0015, and p PET/CT detected 110/111 metastatic lesions (99.1%); BS detected 85 (76.6%) (p PET/BS were 100%/90.3% for the blastic type, 91.7%/8.3% for the lytic type, 100%/100% for the mixed type, and 100%/53.3% for the invisible type, respectively. Significant differences in blastic, lytic, and invisible types were observed between the two methods (p = 0.013, p = 0.0044, and p = 0.023, respectively). In conclusion, 11C-choline PET/CT had greater sensitivity and accuracy than BS for detection of bone involvement in patients with prostate cancer.

No evidence for role of extracellular choline-acetyltransferase in generation of gamma oscillations in rat hippocampal slices in vitro.

Science.gov (United States)

Hollnagel, J O; ul Haq, R; Behrens, C J; Maslarova, A; Mody, I; Heinemann, U

2015-01-22

Acetylcholine (ACh) is well known to induce persistent γ-oscillations in the hippocampus when applied together with physostigmine, an inhibitor of the ACh degrading enzyme acetylcholinesterase (AChE). Here we report that physostigmine alone can also dose-dependently induce γ-oscillations in rat hippocampal slices. We hypothesized that this effect was due to the presence of choline in the extracellular space and that this choline is taken up into cholinergic fibers where it is converted to ACh by the enzyme choline-acetyltransferase (ChAT). Release of ACh from cholinergic fibers in turn may then induce γ-oscillations. We therefore tested the effects of the choline uptake inhibitor hemicholinium-3 (HC-3) on persistent γ-oscillations either induced by physostigmine alone or by co-application of ACh and physostigmine. We found that HC-3 itself did not induce γ-oscillations and also did not prevent physostigmine-induced γ-oscillation while washout of physostigmine and ACh-induced γ-oscillations was accelerated. It was recently reported that ChAT might also be present in the extracellular space (Vijayaraghavan et al., 2013). Here we show that the effect of physostigmine was prevented by the ChAT inhibitor (2-benzoylethyl)-trimethylammonium iodide (BETA) which could indicate extracellular synthesis of ACh. However, when we tested for effects of extracellularly applied acetyl-CoA, a substrate of ChAT for synthesis of ACh, physostigmine-induced γ-oscillations were attenuated. Together, these findings do not support the idea that ACh can be synthesized by an extracellularly located ChAT. Copyright © 2014 IBRO. Published by Elsevier Ltd. All rights reserved.

In vitro inhibition of choline acetyltransferase by a series of 2-benzylidene-3-quinuclidinones

International Nuclear Information System (INIS)

Capacio, B.R.

1988-01-01

Ten substituted 2-benzylidene-3-quinuclidinones were synthesized and evaluated for their relative potency as in vitro inhibitors of choline acetyltransferase (ChAT). Acetylcholine (ACh) synthesis was followed radiometrically by the incorporation of labeled acetate originating from 14 C-acetyl-CoA. Woolf-Augustinsson-Hofstee data analysis was used to calculate Vmax, Km, and Ki values. The inhibition was found to be noncompetitive or uncompetitive with respect to choline. Quantitative structure activity relationship correlations demonstrated a primary dependence on κ-σ, as well as steric properties of the substituted benzene ring. Additional radiometric and spectrophotometric were performed with 2-(3'-methyl)-benzylidene-3-quinuclidinone, one of the more potent analogs, to further elucidate the inhibitory mechanism. ChAT-mediated cleavage of ACh was measured spectrophotometrically by following the appearance of NADH at 340 nanometers in an enzyme coupled assay. Lineweaver-Burk analysis indicated mixed or uncompetitive inhibition with respect to both substrates of the forward reaction, suggesting interference with a rate limiting step

Choline uptake in the hippocampus: inhibition of septal-hippocampal cholinergenic neurons by intraventricular barbiturates

International Nuclear Information System (INIS)

Richter, J.A.

1986-01-01

The author attempts to determine where in the brain pentobarbital acts to cause the inhibition of high-affinity, sodium-dependent choline uptake, and what behavioral consequences result from this particular effect of barbituates. The experiments were done in male Wistar rats which had received an injection of Nivea cream injected directly to the acannula. In the experiments the drug solution injected into the lateral ventricle was also spiked with ( 14 C) - phenobarbital at a final specific activity of 5 dpm/nmole so that a more precise estimate of the spread of drug solution could be made. When a phenobarbital-Fast green Dye mixture was injected bilaterally into the lateral ventricles, the dye was found to have spread through the entire ventricular system when the rat was killed 10-20 min later. Choline uptake in the hippocampus was inhibited and the inhibition was apparently greater of 20 min rather than 10 min were allowed to elapse after the injection

An Incidental Renal Oncocytoma: 18F-Choline PET/MRI

Directory of Open Access Journals (Sweden)

Andrew Mallia

2016-04-01

Full Text Available PET/MRI is a new hybrid imaging modality and has the potential to become a powerful imaging tool. It is currently one of the most active areas of research in diagnostic imaging. The characterisation of an incidental renal lesion can be difficult. In particular, the differentiation of an oncocytoma from other solid renal lesions such as renal cell carcinoma (RCC represents a diagnostic challenge. We describe the detection of an incidental renal oncocytoma in a 79-year gentleman who underwent a re-staging 18F-Choline PET/MRI following a rise in PSA values (4.07, nadir 1.3.

SU-C-303-01: Activation-Induced Cytidine Deaminase Confers Cancer Resistance to Radiation Therapy

International Nuclear Information System (INIS)

Yi, S; La Count, S; Liu, J; Bai, X; Lu, L

2015-01-01

Purpose: To study the role of activation-induced cytidine deaminase (AID) in malignant cell resistance to radiation therapy. Methods: We first developed several small devices that could be used to adopt radiation beams from clinical high dose rate brachy therapy (HDR) or linac-based megavoltage machines to perform pre-clinical cell and mouse experiments. Then we used these devices to deliver radiation to AID-positive and AID-silenced cancer cells or tumors formed by these cells in mice. Cells and mice bearing tumors received the same dose under the same experimental conditions. For cells, we observed the apoptosis and the cell survival rate over time. For mice bearing tumors, we measured and recorded the tumor sizes every other day for 4 weeks. Results: For cell experiments, we found that the AID-positive cells underwent much less apoptosis compared with AID-silenced cells upon radiation. And for mouse experiments, we found that AID-positive tumors grew significantly faster than the AID-silenced tumors despite of receiving the same doses of radiation. Conclusion: Our study suggests that AID may confer cancer resistance to radiation therapy, and AID may be a significant biomarker predicting cancer resistance to radiation therapy for certain cancer types

Choline and methionine differentially alter methyl carbon metabolism in bovine neonatal hepatocytes.

Science.gov (United States)

Chandler, Tawny L; White, Heather M

2017-01-01

Intersections in hepatic methyl group metabolism pathways highlights potential competition or compensation of methyl donors. The objective of this experiment was to examine the expression of genes related to methyl group transfer and lipid metabolism in response to increasing concentrations of choline chloride (CC) and DL-methionine (DLM) in primary neonatal hepatocytes that were or were not exposed to fatty acids (FA). Primary hepatocytes isolated from 4 neonatal Holstein calves were maintained as monolayer cultures for 24 h before treatment with CC (61, 128, 2028, and 4528 μmol/L) and DLM (16, 30, 100, 300 μmol/L), with or without a 1 mmol/L FA cocktail in a factorial arrangement. After 24 h of treatment, media was collected for quantification of reactive oxygen species (ROS) and very low-density lipoprotein (VLDL), and cell lysates were collected for quantification of gene expression. No interactions were detected between CC, DLM, or FA. Both CC and DLM decreased the expression of methionine adenosyltransferase 1A (MAT1A). Increasing CC did not alter betaine-homocysteine S-methyltranferase (BHMT) but did increase 5-methyltetrahydrofolate-homocysteine methyltransferase (MTR) and methylenetetrahydrofolate reductase (MTHFR) expression. Increasing DLM decreased expression of BHMT and MTR, but did not affect MTHFR. Expression of both phosphatidylethanolamine N-methyltransferase (PEMT) and microsomal triglyceride transfer protein (MTTP) were decreased by increasing CC and DLM, while carnitine palmitoyltransferase 1A (CPT1A) was unaffected by either. Treatment with FA decreased the expression of MAT1A, MTR, MTHFR and tended to decrease PEMT but did not affect BHMT and MTTP. Treatment with FA increased CPT1A expression. Increasing CC increased secretion of VLDL and decreased the accumulation of ROS in media. Within neonatal bovine hepatocytes, choline and methionine differentially regulate methyl carbon pathways and suggest that choline may play a critical role in

Synergistic effects of ginseng stem and leaf-extracted ginsenoside and choline on improving learning and memory in rats Association verification experiment in animals with multiple learning and memory Disorders

Institute of Scientific and Technical Information of China (English)

Xiaomin Zhao; Hongxia Gu; Qing Li; Xianglin Xie; Zuoli Xia; Hongxin Cai; Ling Zhang; Dawei Li; Xinnong Wang

2008-01-01

BACKGROUND:Ginsenoside extracted from the stem and leaf of ginseng(GSL)and choline have both been shown to improve learning and memory functions; however,further studies are needed to understand the synergistic effects of a combination of both.OBJECTIVE:To verify the combined improved synergistic effects of GSL and choline on learning and memory disorders in rats.DESIGN:Control observation.SETTING:Taishan Medical College.MATERIALS:A total of 150 male Kunming mice weighing(20±2)g and 40 healthy male Wistar rats weighing(220±20)g were provided by the Experimental Animal Department of Jilin University.Animal experimentation received confirmed consent from the local ethic committee.GSL was provided by the Department of Chemistry,Norman Bethune Medical University,and choline was provided by the Third Experiment Factory,Shanghai.METHODS:This study was performed at the Life Science Institute,Taishan Medical College from October 2006 to February 2007.①Scopolamine-induced learning and memory disorders in rats:Forty rats were randomly divided into control group,model group,combination group(400 mg/kg GSL + 200 mg/kg choline),GSL(400 mg/kg)group,and choline(200 mg/kg)group,8 rats/group.Rats were perfused and administrated in the morning,once a day for 14 successive days.Rats in the control group and model group were perfused with 20 mL/kg distilled water and underwent Morris water maze spatial resolution test 1 hour after perfusion on the 10th,11th,and 12th days after administration.Rats also underwent passive step-down avoidance test 1 hour after reperfusion on the 13th and 14th days after administration.Thirty minutes prior to experimentation,rats in the remaining three groups were intraperitoneally(I.p)injected with 2 mg/kg scopolamine,and rats in the control group were I.p.injected with 2 mL/kg saline.②Scopolamine-induced learning disorder and memory acquired disorder in mice:Fifty mice were randomly divided into control group,model group,combination group(400 mg

Diagnostic value of combining {sup 11}C-choline and {sup 18}F-FDG PET/CT in hepatocellular carcinoma

Energy Technology Data Exchange (ETDEWEB)

Castilla-Lievre, Maria-Angela [University Department Hepatinov, Assistance-Publique Hopitaux de Paris, Department of Nuclear Medicine, Hopital Antoine Beclere, Clamart (France); IMIV - UMR 1023 Inserm/CEA/Universite Paris Sud - ERL 9218 CNRS, Orsay (France); Franco, Dominique [Universite Paris-Sud, Department of Surgery, Hopital Antoine Beclere, University Department Hepatinov, Assistance-Publique Hopitaux de Paris, Clamart (France); Gervais, Philippe; Kuhnast, Bertrand; Desarnaud, Serge; Helal, Badia-Ourkia [IMIV - UMR 1023 Inserm/CEA/Universite Paris Sud - ERL 9218 CNRS, Orsay (France); CEA, DSV, I2BM, Service Hospitalier Frederic Joliot, Orsay (France); Agostini, Helene [University Department Hepatinov, Assistance-Publique Hopitaux de Paris, Clinical Research Unit of Hopitaux universitaires Paris-Sud, Hopital Kremlin Bicetre (France); Marthey, Lysiane [Universite Paris-Sud, Department of Gastroenterology, Hopital Antoine Beclere, University Department Hepatinov, Assistance-Publique Hopitaux de Paris, Clamart (France)

2016-05-15

In this prospective study, our goal was to emphasize the diagnostic value of combining {sup 11}C-choline and {sup 18}F-FDG PET/CT for hepatocellular carcinoma (HCC) in patients with chronic liver disease. Thirty-three consecutive patients were enrolled. All patients were suspected to have HCC based on CT and/or MRI imaging. A final diagnosis was obtained by histopathological examination or by imaging alone according to American Association for the Study of Liver Disease criteria. All patients underwent PET/CT with both tracers within a median of 5 days. All lesions showing higher tracer uptake than normal liver were considered positive for HCC. We examined how tracer uptake was related to biological (serum α-fetoprotein levels) and pathological (differentiation status, peritumoral capsule and vascular invasion) prognostic markers of HCC, as well as clinical observations at 6 months (recurrence and death). Twenty-eight HCC, four cholangiocarcinomas and one adenoma were diagnosed. In the HCC patients, the sensitivity of {sup 11}C-choline, {sup 18}F-FDG and combined {sup 11}C-choline and {sup 18}F-FDG PET/CT for the detection of HCC was 75 %, 36 % and 93 %, respectively. Serum α-fetoprotein levels >200 ng/ml were more frequent among patients with {sup 18}F-FDG-positive lesions than those with {sup 18}F-FDG-negative lesions (p < 0.05). Early recurrence (n=2) or early death (n=5) occurred more frequently in patients with {sup 18}F-FDG-positive lesions than in those with {sup 18}F-FDG-negative lesions (p < 0.05). The combined use of {sup 11}C-choline and {sup 18}F-FDG PET/CT detected HCC with high sensitivity. This approach appears to be of potential prognostic value and may facilitate the selection of patients for surgical resection or liver transplantation. (orig.)

Effects of in ovo administration of betaine and choline on hatchability results, growth and carcass characteristics and immune response of broiler chickens

Directory of Open Access Journals (Sweden)

Jafar Gholami

2015-05-01

Full Text Available The effect of in ovo administration of different levels of betaine and choline on egg hatchability, immune response, growth and carcass traits of broiler chickens was studied. Four thousand hatching eggs from Ross 308 broiler breeder layers, weighed individually, were incubated for 21 days in a commercial hatchery. At 12th day of incubation, 3456 fertilized eggs were randomly divided into 8 experimental groups of 3 replicates each (144 eggs per replicate: negative control (NC – not injected; positive control (PC – injected with 0.5 mL deionized water; Bet 0.25 – injected with 0.5 mL deionized water+0.25 mg soluble betaine; Bet 0.375 – injected with 0.5 mL deionized water+0.375 mg soluble betaine; Bet 0.50 – injected with 0.5 mL deionized water+0.50 mg soluble betaine; Chol 0.25 – injected with 0.5 mL deionized water+0.25 mg soluble choline; Chol 0.375 – injected with 0.5 mL deionized water+0.375 mg soluble choline; Chol 0.50 – injected with 0.5 mL deionized water+0.50 mg soluble choline. Among the hatched chickens, 360 males were randomly chosen (45 for each group and were grown up to 42nd day of age. The embryo mortality, pecked eggs, infected eggs and hatchability percentages were similar among the experimental groups. The betaine and choline treatments improved hatching weight and final weight of chickens, while reduced feed conversion ratio and abdominal fat percentage. No effect on carcass yield, and breast muscle, leg and wings percentages, as well as on immunoglobulin M (IgM, G (IgG, and total antibody (IgT titers was observed. The treatments had little effect on internal organs.

Studies of antimony telluride and copper telluride films electrodeposition from choline chloride containing ionic liquids

Energy Technology Data Exchange (ETDEWEB)

Catrangiu, Adriana-Simona; Sin, Ion [Department of Inorganic Chemistry, Physical Chemistry and Electrochemistry, POLITEHNICA University of Bucharest, Calea Grivitei 132, Bucharest (Romania); Prioteasa, Paula [INCDIE ICPE-Advanced Research, Splaiul Unirii 313, Bucharest (Romania); Cotarta, Adina [Department of Inorganic Chemistry, Physical Chemistry and Electrochemistry, POLITEHNICA University of Bucharest, Calea Grivitei 132, Bucharest (Romania); Cojocaru, Anca, E-mail: a_cojocaru@chim.upb.ro [Department of Inorganic Chemistry, Physical Chemistry and Electrochemistry, POLITEHNICA University of Bucharest, Calea Grivitei 132, Bucharest (Romania); Anicai, Liana [Center of Surface Science and Nanotechnology, University POLITEHNICA of Bucharest, Splaiul Independentei 313, Bucharest (Romania); Visan, Teodor [Department of Inorganic Chemistry, Physical Chemistry and Electrochemistry, POLITEHNICA University of Bucharest, Calea Grivitei 132, Bucharest (Romania)

2016-07-29

Cyclic voltammetry and electrochemical impedance spectroscopy were used to investigate the deposition of antimony telluride or copper telluride from ionic liquid consisting in mixture of choline chloride with oxalic acid. In addition, the cathodic process during copper telluride formation was studied in the mixture of choline chloride with ethylene glycol. The results indicate that the Pt electrode is first covered with a Te layer, and then the more negative polarisation leads to the deposition of Sb{sub x}Te{sub y} or Cu{sub x}Te{sub y} semiconductor compounds. Thin films were deposited on copper and carbon steel at 60–70 °C and were characterised by scanning electron microscopy, energy X-ray dispersive spectroscopy (EDS), and X-ray diffraction (XRD). Their stoichiometry depends on the bath composition and applied potential. EDS and XRD patterns indicate the possible synthesis of stoichiometric Sb{sub 2}Te{sub 3} phase and Cu{sub 2}Te, Cu{sub 5}Te{sub 3}, and Cu{sub 2.8}Te{sub 2} phases, respectively, by controlling the ratio of ion concentrations in ionic liquid electrolytes and deposition potential. - Highlights: • Sb{sub x}Te{sub y} and Cu{sub x}Te{sub y} films electrodeposited from choline-chloride-based ionic liquids. • The stoichiometry of film depends on the bath composition and deposition potential. • Sb{sub 2}Te{sub 3}, Cu{sub 2}Te, Cu{sub 5}Te{sub 3}, Cu{sub 2.8}Te{sub 2} phases were identified in X-ray diffraction patterns.

Protein τ-mediated effects on rat hippocampal choline transporters CHT1 and τ-amyloid β interactions

Czech Academy of Sciences Publication Activity Database

Krištofíková, Z.; Řípová, D.; Hegnerová, Kateřina; Šírová, J.; Homola, Jiří

2013-01-01

Roč. 38, č. 9 (2013), s. 1949-1959 ISSN 0364-3190 Institutional support: RVO:67985882 Keywords : Tau protein * Amyloid β peptide * Choline transporter Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 2.551, year: 2013

PET and PET/CT with radiolabeled choline in prostate cancer: a critical reappraisal of 20 years of clinical studies

Energy Technology Data Exchange (ETDEWEB)

Giovacchini, Giampiero; Giovannini, Elisabetta; Leoncini, Rossella; Riondato, Mattia; Ciarmiello, Andrea [S. Andrea Hospital, Nuclear Medicine Department, La Spezia (Italy)

2017-09-15

We here aim to provide a comprehensive and critical review of the literature concerning the clinical applications of positron emission tomography/computed tomography (PET/CT) with radiolabeled choline in patients with prostate cancer (PCa). We will initially briefly summarize the historical context that brought to the synthesis of [{sup 11}C]choline, which occurred exactly 20 years ago. We have arbitrarily grouped the clinical studies in three different periods, according to the year in which they were published and according to their relation with their applications in urology, radiotherapy and oncology. Studies at initial staging and, more extensively, studies in patients with biochemical failure, as well as factors predicting positive PET/CT will be reviewed. The capability of PET/CT with radiolabeled choline to provide prognostic information on PCa-specific survival will also be examined. The last sections will be devoted to the use of radiolabeled choline for monitoring the response to androgen deprivation therapy, radiotherapy, and chemotherapy. The accuracy and the limits of the technique will be discussed according to the information available from standard validation processes, including biopsy or histology. The clinical impact of the technique will be discussed on the basis of changes induced in the management of patients and in the evaluation of the response to therapy. Current indications to PET/CT, as officially endorsed by guidelines, or as routinely performed in the clinical practice will be illustrated. Emphasis will be made on methodological factors that might have influenced the results of the studies or their interpretation. Finally, we will briefly highlight the potential role of positron emission tomography/magnetic resonance and of new radiotracers for PCa imaging. (orig.)

Therapeutic Efficacy of Fenugreek Extract or/and Choline with Docosahexaenoic Acid in Attenuating Learning and Memory Deficits in Ovariectomized Rats

Directory of Open Access Journals (Sweden)

Anjaneyulu K

2018-04-01

Full Text Available Background: Studies have demonstrated that estradiol influences cognitive functions. Phytoestrogens and many other estrogen-like compounds in plants have beneficial effects on cognitive performance in postmenopausal women. However, there is no evident report of fenugreek and choline-Docosahexaenoic Acid (DHA on cognition in ovariectomized rats. Aim and Objectives: The present study was aimed to evaluate the therapeutic efficacy of fenugreek extract or/and choline- DHA in attenuating ovariectomy-induced memory impairment, brain antioxidant status and hippocampal neural cell deficits in the rat model. Material and Methods: Female Wistar 9-10 months old rats were grouped (n=12/group as - (1 Normal Control (NC, (2 Ovariectomized (OVX, (3 OVX+FG (hydroalcoholic seed extract of fenugreek, (4 OVX+C-DHA,(5 OVX+FG+C-DHA and (6 OVX+Estradiol. Groups 2- 6 were bilaterally OVX. FG, C-DHA was supplemented orally for 30 days, 14 days after ovariectomy. Assessment of learning and memory was performed by passive avoidance test. Oxidative stress and antioxidant markers were assessed by standard methods. Nissl stained hippocampal sections were analyzed to determine alterations in neural cell numbers in CA1, CA3 and dentate gyrus. Results: Supplementation of FG or/and choline with DHA to OVX rats, caused significant improvement in learning and memory as well as decreased neural cell deficits compared to the same in OVX rats. Further, significantly reduced levels of brain Malondialdehyde (MDA and increased levels of Glutathione (GSH were observed. Conclusion: Therapeutic supplementation of FG with choline-DHA significantly attenuates ovariectomy-induced neurocognitive deficits in rats.

Pertussis toxin substrate is a guanosine 5'-[beta-thio]diphosphate-, N-ethylmaleimide-, Mg2+- and temperature-sensitive GTP-binding protein.

OpenAIRE

Wong, S K; Martin, B R; Tolkovsky, A M

1985-01-01

We compared the effects of guanine nucleotides and Mg2+ on ADP-ribosylation of rat brain and liver membrane proteins catalysed by Bordetella pertussis toxin (IAP) and cholera toxin (CT). Labelling of proteins in the presence of [alpha-32P]NAD+, ATP and CT required GTP or guanosine 5'-[gamma-thio]triphosphate (GTP [S]). In contrast, labelling of one (liver) or two (brain) polypeptides by IAP was enhanced by guanosine 5'-[beta-thio]diphosphate (GDP[S]) or GTP, but was blocked by GTP[S] or guano...

Theoretical pKa prediction of the α-phosphate moiety of uridine 5‧-diphosphate-GlcNAc

Science.gov (United States)

Vipperla, Bhavaniprasad; Griffiths, Thomas M.; Wang, Xingyong; Yu, Haibo

2017-01-01

The pKa value of the α-phosphate moiety of uridine 5‧-diphosphate-GlcNAc (UDP-GlcNAc) has been successfully calculated using density functional theory methods in conjunction with the Polarizable Continuum Models. Theoretical methods were benchmarked over a dataset comprising of alkyl phosphates. B3LYP/6-31+G(d,p) calculations using SMD solvation model provide excellent agreement with the experimental data. The predicted pKa for UDP-GlcNAc is consistent with most recent NMR studies but much higher than what it has long been thought to be. The importance of this study is evident that the predicted pKa for UDP-GlcNAc supports its potential role as a catalytic base in the substrate-assisted biocatalysis.

Effects of betaine supplementation and choline deficiency on folate deficiency-induced hyperhomocysteinemia in rats.

Science.gov (United States)

Liu, Ying; Liu, Yi-qun; Morita, Tatsuya; Sugiyama, Kimio

2012-01-01

The effect of betaine status on folate deficiency-induced hyperhomocysteinemia was investigated to determine whether folate deficiency impairs homocysteine removal not only by the methionine synthase (MS) pathway but also by the betaine-homocysteine S-methyltransferase (BHMT) pathway. For this purpose, we investigated the effect of dietary supplementation with betaine at a high level (1%) in rats fed a folate-deprived 10% casein diet (10C) and 20% casein diet (20C). We also investigated the effect of choline deprivation on folate deficiency-induced hyperhomocysteinemia in rats fed 20C. Supplementation of folate-deprived 10C and 20C with 1% betaine significantly suppressed folate deprivation-induced hyperhomocysteinemia, but the extent of suppression was partial or limited, especially in rats fed 10C, the suppression of plasma homocysteine increment being 48.5% in rats fed 10C and 69.7% in rats fed 20C. Although betaine supplementation greatly increased hepatic betaine concentration and BHMT activity, these increases did not fully explain why the effect of betaine supplementation was partial or limited. Folate deprivation markedly increased the hepatic concentration of N,N-dimethylglycine (DMG), a known inhibitor of BHMT, and there was a significant positive correlation between hepatic DMG concentration and plasma homocysteine concentration, suggesting that folate deficiency increases hepatic DMG concentration and thereby depresses BHMT reaction, leading to interference with the effect of betaine supplementation. Choline deprivation did not increase plasma homocysteine concentration in rats fed 20C, but it markedly enhanced plasma homocysteine concentration when rats were fed folate-deprived 20C. This indicates that choline deprivation reinforced folate deprivation-induced hyperhomocysteinemia. Increased hepatic DMG concentration was also associated with such an effect. These results support the concept that folate deficiency impairs homocysteine metabolism not only

Comparison of {sup 68}Ga-labelled PSMA-11 and {sup 11}C-choline in the detection of prostate cancer metastases by PET/CT

Energy Technology Data Exchange (ETDEWEB)

Schwenck, Johannes [Eberhard Karls University, Department of Nuclear Medicine and Clinical Molecular Imaging, Tuebingen (Germany); Eberhard Karls University, Department of Preclinical Imaging and Radiopharmacy, Tuebingen (Germany); Rempp, Hansjoerg; Nikolaou, Konstantin; Pfannenberg, Christina [Eberhard Karls University, Department of Diagnostic and Interventional Radiology, Tuebingen (Germany); Reischl, Gerald [Eberhard Karls University, Department of Preclinical Imaging and Radiopharmacy, Tuebingen (Germany); Kruck, Stephan; Stenzl, Arnulf [Eberhard Karls University, Department of Urology, Tuebingen (Germany); La Fougere, Christian [Eberhard Karls University, Department of Nuclear Medicine and Clinical Molecular Imaging, Tuebingen (Germany); German Cancer Consortium, German Cancer Research Center Partner Site, Heidelberg (Germany)

2017-01-15

Prostate-specific membrane antigen (PSMA) is expressed ubiquitously on the membrane of most prostate tumors and its metastasis. While PET/CT using {sup 11}C-choline was considered as the gold standard in the staging of prostate cancer, PET with radiolabelled PSMA ligands was introduced into the clinic in recent years. Our aim was to compare the PSMA ligand {sup 68}Ga-PSMA-11 with {sup 11}C-choline in patients with primary and recurrent prostate cancer. 123 patients underwent a whole-body PET/CT examination using {sup 68}Ga-PSMA-11 and {sup 11}C-choline. Suspicious lesions were evaluated visually and semiquantitatively (SUVavg). Out of these, 103 suffered from a confirmed biochemical relapse after prostatectomy and/or radiotherapy (mean PSA level of 4.5 ng/ml), while 20 patients underwent primary staging. In 67 patients with biochemical relapse, we detected 458 lymph nodes suspicious for metastasis. PET using {sup 68}Ga-PSMA-11 showed a significantly higher uptake and detection rate than {sup 11}C-choline PET. Also {sup 68}Ga-PSMA-11 PET identified significantly more patients with suspicious lymph nodes as well as affected lymph nodes regions especially at low PSA levels. Bone lesions suspicious for prostate cancer metastasis were revealed in 36 patients' biochemical relapse. Significantly more bone lesions were detected by {sup 68}Ga-PSMA-11, but only 3 patients had only PSMA-positive bone lesions. Nevertheless, we detected also 29 suspicious lymph nodes and 8 bone lesions, which were only positive as per {sup 11}C-choline PET. These findings led to crucial differences in the TNM classification and the identification of oligometastatic patients. In the patients who underwent initial staging, all primary tumors showed uptake of both tracers. Although significantly more suspicious lymph nodes and bone lesions were identified, only 2 patients presented with bone lesions only detected by {sup 68}Ga-PSMA-11 PET. Thus, PET using {sup 68}Ga-PSMA-11 showed a higher

Novel concept of enzyme selective nicotinamide adenine dinucleotide (NAD)-modified inhibitors based on enzyme taxonomy from the diphosphate conformation of NAD.

Science.gov (United States)

Fujii, Mikio; Kitagawa, Yasuyuki; Iida, Shui; Kato, Keisuke; Ono, Machiko

2015-11-15

The dihedral angle θ of the diphosphate part of NAD(P) were investigated to distinguish the differences in the binding-conformation of NAD(P) to enzymes and to create an enzyme taxonomy. Furthermore, new inhibitors with fixed dihedral angles showed that enzymes could recognize the differences in the dihedral angle θ. We suggest the taxonomy and the dihedral angle θ are important values for chemists to consider when designing inhibitors and drugs that target enzymes. Copyright © 2015 Elsevier Ltd. All rights reserved.

Spectrophotometric determination of Sc in eriochrome cyanine R(chrome azurol S) - phosphatidyl choline system

International Nuclear Information System (INIS)

Xu, Y.; Chen, X.; Hu, Z.

1987-01-01

Eriochrome cyanine R(chrome azurol S) is used as a color reagent to determine Sc in the presence of phosphatidyl choline, eta = 3.7 * 10 4 (4.5 * 10 4 ). This method has been connected to extraction separation to determine Sc in the presence of rare earth elements, and good results have been obtained. Phosphatidyl choline(PC) is a biochemical reagent, which can be used as a surfactant. It has been reported that chrome azurol S(CAS) can be used to determine Be in the presence of PC but it has not been reported that eriochrome cyanine R(ECR) and CAS can been used to determine Sc in the presence of PC. This paper has put forward a method by which Sc can be determined. ECR (CAS) has been used as a color reagent and PC as a surfactant. Conditional experiments have been made and this method has been connected to extraction separation. Tributyl phosphate (TBP) extracts Sc from rare earth elements to make a determination and good results have been obtained

MTHFR deficiency or reduced intake of folate or choline in pregnant mice results in impaired short-term memory and increased apoptosis in the hippocampus of wild-type offspring.

Science.gov (United States)

Jadavji, N M; Deng, L; Malysheva, O; Caudill, M A; Rozen, R

2015-08-06

Genetic or nutritional disturbances in one-carbon metabolism, with associated hyperhomocysteinemia, can result in complex disorders including pregnancy complications and neuropsychiatric diseases. In earlier work, we showed that mice with a complete deficiency of methylenetetrahydrofolate reductase (MTHFR), a critical enzyme in folate and homocysteine metabolism, had cognitive impairment with disturbances in choline metabolism. Maternal demands for folate and choline are increased during pregnancy and deficiencies of these nutrients result in several negative outcomes including increased resorption and delayed development. The goal of this study was to investigate the behavioral and neurobiological impact of a maternal genetic deficiency in MTHFR or maternal nutritional deficiency of folate or choline during pregnancy on 3-week-old Mthfr(+/+) offspring. Mthfr(+/+) and Mthfr(+/-) females were placed on control diets (CD); and Mthfr(+/+) females were placed on folate-deficient diets (FD) or choline-deficient diets (ChDD) throughout pregnancy and lactation until their offspring were 3weeks of age. Short-term memory was assessed in offspring, and hippocampal tissue was evaluated for morphological changes, apoptosis, proliferation and choline metabolism. Maternal MTHFR deficiency resulted in short-term memory impairment in offspring. These dams had elevated levels of plasma homocysteine when compared with wild-type dams. There were no differences in plasma homocysteine in offspring. Increased apoptosis and proliferation was observed in the hippocampus of offspring from Mthfr(+/-) mothers. In the maternal FD and ChDD study, offspring also showed short-term memory impairment with increased apoptosis in the hippocampus; increased neurogenesis was observed in ChDD offspring. Choline acetyltransferase protein was increased in the offspring hippocampus of both dietary groups and betaine was decreased in the hippocampus of FD offspring. Our results reveal short-term memory

Significance of determination of serum cytidine deaminase (CD) levels for diagnosis of active rheumatoid arthritis (RA)

International Nuclear Information System (INIS)

Xiao Chuangqing; Jang Xiaogong; He Yunnan

2005-01-01

Objective: To determine the clinical value of measurement of serum cytidine deaminase (CD) levels in patients with active rheumatoid arthritis (RA). Methods: Serum levels of CD were detected with spectrophotometry, in 33 patients with active RA and 60 controls. The erythrocyte sedimentation rate (ESR) and CRP content were also determined in both groups. Results: The ser- um CD contents in patients with active RA(14.80 ± 2.11U/ml) were significantly higher than those in controls(4.86±1.86 U/ml,P<0.01). The CRP contents (51.46 ± 20.43mg/L) and ESR readings(85.03 ± 27.6mm/h) in the patients were also significantly higher than those in the controls(3.40 ± 2.21mg/L and 13.04 ± 4.89mm/h respectively, all P<0.01). In the patients, the serum CD contents were linearly positively correlated with the ESR contents and CRP readings (r=0.6324 and 0.8013 respectively, P <0.01). Conclusion: Serum CD is an early biochemical marker for diagnosis of active rheumatoid arthritis and is also of prognostic value. (authors)

SALT ACCLIMATION OF TRITICUM-AESTIVUM BY CHOLINE CHLORIDE - PLANT-GROWTH, MINERAL-CONTENT, AND CELL-PERMEABILITY

NARCIS (Netherlands)

MANSOUR, MM; STADELMANN, EJ; LEESTADELMANN, OY

1993-01-01

Seedlings of a salt sensitive line of Triticum aestivum were grown in Hoagland solution supplemented with 100 mM NaCl following a pretreatment with choline chloride (ChCl). Changes in growth, mineral content of roots and shoots, and passive permeability of the cell membrane were measured. Relative

Incorporation of radioactive labelled cholin and palmitate into lung lecithin of rabbits treated with high doses of bromcarbamides, barbiturates and diazepam

International Nuclear Information System (INIS)

Wichert, P. von; Schmidt, C.; Pomraenke, K.; Wiegers, U.

1977-01-01

Severe intoxications with bromcarbamides often show respiratory complications. To answer the question if there is a direct effect of the drug on lung tissue the incorporation of radioactive labelled choline and palmitate into lung lecithin was investigated. The phospholipid metabolism is in close relation to the surfactant system of the lung. Secondly the influence of bromcarbamides was compared with other hypnotic drugs. There was a reduction of palmitate incorporation into lung lecithin down to 40%, whereas the incorporation of choline increases in bromcarbamide intoxication. The relation between palmitate and choline incorporation was 6.77 in the controls and it decreases to 2-3 in the bromcarbamide group. The total phospholipid content in the lung/g wet weight remained unchanged in all experiments. From this data it is concluded, that these drugs cause a reduction of fatty acid exchange of the lecithin molecules of the lung. This might lead to the production of non surface active lecithin. The clinical and the morphological aspects of severe bromcarbamide intoxication are consistent with a perturbation of the surfactant function. (orig./MG) [de

Formation of nicotinamide ribose diphosphate ribose, a new metabolite of the NAD pathway, by growing mycelium of Aspergillus niger

International Nuclear Information System (INIS)

Kuwahara, Masaaki

1976-01-01

A new step of NAD metabolism was shown in Aspergillus niger. Radioactive nicotinic acid and nicotinamide were incorporated into nicotinamide ribose diphosphate ribose (NAm-RDPR), which had been isolated from the culture filtrate. Its content in the culture medium increased with an increase of culture time, and this compound was proved to be a terminal metabolite in the NAD pathway. The experimental results also showed that the Preiss-Handler pathway and the NAD cycling system function in the NAD biosynthesis in A. niger. A part of the radioactive precursors was also incorporated into an unknown compound. (auth.)

Effects of ginsenoside of stem and leaf combined with choline on learning and memory ability of rat models with Alzheimer diseases

Institute of Scientific and Technical Information of China (English)

Xiaomin Zhao; Xianglin Xie; Zuoli Xia; Yunsheng Gao; Yuyun Zhu; Hongxia Gu

2006-01-01

BACKGROUND: Central adrenergic nerve and 5-serotonergic nerve can influence central cholinergic nerve on learning and memory and make easy for study; however, ginsenoside of stem and leaf (GSL) can improve functions of central adrenergic nerve; moreover, 5-serotonergic nerve and the combination with choline can produce synergistic effect and enhance learning and memory ability so as to improve learning and memory disorder of patients with Alzheimer disease (AD).OBJECTIVE: To observe the effects of GSL combining with choline on learning and memory of AD model rats.DESIGN: Randomized grouping design and controlled animal study.SETTING: Department of Pharmacology, Taishan Medical College.MATERIALS: The experiment was carried out in the Pharmacological Department of Medical College of Jilin University from October 1996 to January 1997. Forty healthy male Wistar rats of clean grade were randomly divided into 5 groups, including sham-injury group, model group, GSL group, choline group and combination group, with 8 rats in each group. Main medications: GSL with the volume more than 92.8% was provided by Department of Chemistry, Norman Bethune Medical College of Jilin University. Panaxatriol, the main component, was detected with thin layer scanning technique and regarded as the index of GSL quality [(55±1)%, CV= 2%, n= 5]. Choline was provided by the Third Shanghai Laboratory Factory.METHODS: 150 nmol quinolinic acid was used to damage bilateral Meynert basal nuclei of adult rats so as to establish AD models. Rats in GSL, choline and combination groups were intragastric administrated with 400 mg/kg GSL, 200 mg/kg choline (20 mL/kg), and both respectively last for 17 days starting from two days 400 mg/kg GSL, 200 mg/kg choline (20 mL/kg), and both respectively last for 17 days starting from two days before operation. Rats in sham-injury group and model group were perfused with the same volume of distilled jumped up safe platform when they were shocked with 36 V

Conductivity and electrochemical stability of concentrated aqueous choline chloride solutions

Science.gov (United States)

Grishina, E. P.; Kudryakova, N. O.

2017-10-01

The conductivity and electrochemical stability of choline chloride (ChCl) solutions with water contents ranging from 20 to 39 wt % are studied. Exposing ChCl to moist ambient air yields a highly concentrated aqueous solution that, as an electrolyte, exhibits the properties and variations in conductivity with temperature and concentration characteristic of other similar systems. Its electrochemical stability window, determined by cyclic voltammetry, is comparable to that of ChCl-based deep eutectic solvents (DESs). Products of the electrolysis of ChCl‒H2O mixtures seem to be less toxic than those of Reline, Ethaline, and Maline.

Effect of rumen-protected choline on performance, blood metabolites, and hepatic triacylglycerols of periparturient dairy cattle

NARCIS (Netherlands)

Zom, R.L.G.; Baal, van J.; Goselink, R.M.A.; Bakker, J.A.; Veth, M.J.; Vuuren, van A.M.

2011-01-01

The effects of a dietary supplement of rumen-protected choline on feed intake, milk yield, milk composition, blood metabolites, and hepatic triacylglycerol were evaluated in periparturient dairy cows. Thirty-eight multiparous cows were blocked into 19 pairs and then randomly allocated to either one

Prospective study on dietary intakes of folate, betaine, and choline and cardiovascular disease risk in women.

NARCIS (Netherlands)

Dalmeijer, G.W.; Olthof, M.R.; Verhoef, P.; Bots, M.L.; van der Schouw, Y.T.

2008-01-01

Objective: To investigate the association between dietary intakes of folate, betaine and choline and the risk of cardiovascular disease (CVD). Design: Prospective cohort study. Subjects: A total of 16165 women aged 49-70 years without prior CVD. Subjects were breast cancer screening participants in

Is There an Additional Value of 11C-Choline PET-CT to T2-weighted MRI Images in the Localization of Intraprostatic Tumor Nodules?

International Nuclear Information System (INIS)

Van den Bergh, Laura; Koole, Michel; Isebaert, Sofie; Joniau, Steven; Deroose, Christophe M.; Oyen, Raymond; Lerut, Evelyne; Budiharto, Tom; Mottaghy, Felix; Bormans, Guy; Van Poppel, Hendrik; Haustermans, Karin

2012-01-01

Purpose: To investigate the additional value of 11 C-choline positron emission tomography (PET)-computed tomography (CT) to T2-weighted (T2w) magnetic resonance imaging (MRI) for localization of intraprostatic tumor nodules. Methods and Materials: Forty-nine prostate cancer patients underwent T2w MRI and 11 C-choline PET-CT before radical prostatectomy and extended lymphadenectomy. Tumor regions were outlined on the whole-mount histopathology sections and on the T2w MR images. Tumor localization was recorded in the basal, middle, and apical part of the prostate by means of an octant grid. To analyze 11 C-choline PET-CT images, the same grid was used to calculate the standardized uptake values (SUV) per octant, after rigid registration with the T2w MR images for anatomic reference. Results: In total, 1,176 octants were analyzed. Sensitivity, specificity, and accuracy of T2w MRI were 33.5%, 94.6%, and 70.2%, respectively. For 11 C-choline PET-CT, the mean SUV max of malignant octants was significantly higher than the mean SUV max of benign octants (3.69 ± 1.29 vs. 3.06 ± 0.97, p mean values (2.39 ± 0.77 vs. 1.94 ± 0.61, p mean and absolute tumor volume (Spearman r = 0.3003, p = 0.0362). No correlation was found between SUVs and prostate-specific antigen, T-stage or Gleason score. The highest accuracy (61.1%) was obtained with a SUV max cutoff of 2.70, resulting in a sensitivity of 77.4% and a specificity of 44.9%. When both modalities were combined (PET-CT or MRI positive), sensitivity levels increased as a function of SUV max but at the cost of specificity. When only considering suspect octants on 11 C-choline PET-CT (SUV max ≥ 2.70) and T2w MRI, 84.7% of these segments were in agreement with the gold standard, compared with 80.5% for T2w MRI alone. Conclusions: The additional value of 11 C-choline PET-CT next to T2w MRI in detecting tumor nodules within the prostate is limited.

Self irradiation effects on the thorium phosphate diphosphate dissolution (TPD): simulation by external irradiations

International Nuclear Information System (INIS)

Tamain, C.; Ozgumus, A.; Dacheux, N.; Garrido, F.; Thome, L.; Corbel, C.; Genet, M.

2004-01-01

The Thorium Phosphate Diphosphate (TPD), proposed as a ceramic for the long term immobilization of actinides, was externally irradiated with several ions and energies (but also with gamma rays) in order to simulate the self-irradiation. The influence of the electronic energy loss was first investigated. Thus, the XRD measurements have shown a complete amorphization of the material under 10 13 ions of Kr.cm -2 , while no significant structural change occurred after 5.10 13 S.cm -2 , 2.10 16 He.cm -2 or 320 kGy of dose of gamma rays. The dissolution of the raw and irradiated pellets was studied versus several parameters such as amorphized fraction, energy loss of incident ions, radiolytic species produced in situ in the leachate during irradiation (such as H 2 O 2 ), temperature and acidity. The results reveal an important increase of the dissolution kinetics for amorphized pellets compared to raw ceramic. (authors)

Activation of G-proteins by receptor-stimulated nucleoside diphosphate kinase in Dictyostelium.

Science.gov (United States)

Bominaar, A A; Molijn, A C; Pestel, M; Veron, M; Van Haastert, P J

1993-01-01

Recently, interest in the enzyme nucleoside diphosphate kinase (EC2.7.4.6) has increased as a result of its possible involvement in cell proliferation and development. Since NDP kinase is one of the major sources of GTP in cells, it has been suggested that the effects of an altered NDP kinase activity on cellular processes might be the result of altered transmembrane signal transduction via guanine nucleotide-binding proteins (G-proteins). In the cellular slime mould Dictyostelium discoideum, extracellular cAMP induces an increase of phospholipase C activity via a surface cAMP receptor and G-proteins. In this paper it is demonstrated that part of the cellular NDP kinase is associated with the membrane and stimulated by cell surface cAMP receptors. The GTP produced by the action of NDP kinase is capable of activating G-proteins as monitored by altered G-protein-receptor interaction and the activation of the effector enzyme phospholipase C. Furthermore, specific monoclonal antibodies inhibit the effect of NDP kinase on G-protein activation. These results suggest that receptor-stimulated NDP kinase contributes to the mediation of hormone action by producing GTP for the activation of GTP-binding proteins. Images PMID:8389692

Organic cation transporter 2 (SLC22A2), a low-affinity and high-capacity choline transporter, is preferentially enriched on synaptic vesicles in cholinergic neurons.

Science.gov (United States)

Nakata, T; Matsui, T; Kobayashi, K; Kobayashi, Y; Anzai, N

2013-11-12

Organic cation transporters (OCTs) are expressed mainly in the kidney and liver. OCTs transport intrinsic organic cations, including monoamine, dopamine, serotonine and choline, across the plasma membrane. Here, we demonstrate that OCT2 (SLC22A2) is expressed in cholinergic neurons, motoneurons in the anterior horn of the spinal cord, and is implicated in acetylcholine (Ach) recycling in presynaptic terminals. Application of rabbit anti-peptide antibody revealed that OCT2 was expressed in the anterior horn of the spinal cord. Double immunostaining of muscle sections with anti-OCT2 and alpha-bungarotoxin (BTX) revealed that OCT2 was localized in the neuromuscular junctions (NMJs). Immunoelectron microscopy revealed that OCT2 was localized both in synaptic vesicles (SVs) in presynaptic terminals around the motoneurons (C-terminals) and in SVs in nerve terminals in NMJs. The similarity in the distribution of OCT2 in cholinergic neurons and that of vesicular acetyl choline transporter (VAchT), and the fact that OCT2 can transport choline suggest that OCT2 could work as a low-affinity and high-capacity choline transporter at presynaptic terminals in cholinergic neurons in a firing-dependent manner. Copyright © 2013 IBRO. Published by Elsevier Ltd. All rights reserved.

Effect of dietary γ-aminobutyric acid on the nerve growth factor and the choline acetyltransferase in the cerebral cortex and hippocampus of ovariectomized female rats.

Science.gov (United States)

Tujioka, Kazuyo; Thanapreedawat, Panicha; Yamada, Takashi; Yokogoshi, Hidehiko; Horie, Kenji; Kim, Mujo; Tsutsui, Kazumi; Hayase, Kazutoshi

2014-01-01

The brain protein synthesis and the plasma concentration of growth hormone (GH) is sensitive to the dietary γ-aminobutyric acid (GABA) in ovariectomized female rats; however, the role of dietary GABA on biomarkers including nerve growth factor (NGF) and choline acetyltransferase for the function of cholinergic neurons remains unknown in ovariectomized female rats. The purpose of this study was to determine whether the dietary GABA affects the concentration and mRNA level of NGF, and the activity of choline acetyltransferase in the brains of ovariectomized female rats. Experiments were done on two groups of 24-wk-old ovariectomized female rats given 0 or 0.5% GABA added to a 20% casein diet. The concentrations of NGF and activities of choline acetyltransferase in the cerebral cortex and hippocampus, and mRNA level of NGF in the hippocampus increased significantly with the 20% casein+0.5% GABA compared with the 20% casein diet alone. In the hippocampus, the mRNA level of NGF significantly correlated with the NGF concentration (r=0.714, pGABA to ovariectomized female rats is likely to control the mRNA level and concentration of NGF and cause an increase in the activity of choline acetyltransferase in the brains.

Therapy assessment in prostate cancer using choline and PSMA PET/CT

Energy Technology Data Exchange (ETDEWEB)

Ceci, Francesco; Castellucci, Paolo; Fanti, Stefano [University of Bologna, Nuclear Medicine Unit, S. Orsola-Malpighi University Hospital, Bologna (Italy); Herrmann, Ken [University Hospital Essen, Department of Nuclear Medicine, Essen (Germany); University of California Los Angeles, Department of Molecular and Medical Pharmacology, David Geffen School of Medicine, Los Angeles, CA (United States); Hadaschik, Boris [University Hospital Essen, Department of Urology, Essen (Germany)

2017-08-15

While PET with non-FDG tracers (mainly choline and Ga-PSMA) has commonly been used for restaging in men with biochemically recurrent prostate cancer, as well as for primary staging, it is only recently that a few preliminary studies have addressed the possible use of PET for monitoring the response to systemic therapy of metastatic disease, especially innovative treatments such as abiraterone and enzalutamide. This article aims to evaluate the role of PET imaging with different non-FDG radiotracers for assessment of therapy in advanced prostate cancer patients. (orig.)

Multilayer Choline Phosphate Molecule Modified Surface with Enhanced Cell Adhesion but Resistance to Protein Adsorption.

Science.gov (United States)

Chen, Xingyu; Yang, Ming; Liu, Botao; Li, Zhiqiang; Tan, Hong; Li, Jianshu

2017-08-22

Choline phosphate (CP), which is a new zwitterionic molecule, and has the reverse order of phosphate choline (PC) and could bind to the cell membrane though the unique CP-PC interaction. Here we modified a glass surface with multilayer CP molecules using surface-initiated atom-transfer radical polymerization (SI-ATRP) and the ring-opening method. Polymeric brushes of (dimethylamino)ethyl methacrylate (DMAEMA) were synthesized by SI-ATRP from the glass surface. Then the grafted PDMAEMA brushes were used to introduce CP groups to fabricate the multilayer CP molecule modified surface. The protein adsorption experiment and cell culture test were used to evaluate the biocompatibility of the modified surfaces by using human umbilical veinendothelial cells (HUVECs). The protein adsorption results demonstrated that the multilayer CP molecule decorated surface could prevent the adsorption of fibrinogen and serum protein. The adhesion and proliferation of cells were improved significantly on the multilayer CP molecule modified surface. Therefore, the biocompatibility of the material surface could be improved by the modified multilayer CP molecule, which exhibits great potential for biomedical applications, e.g., scaffolds in tissue engineering.

Immunolocalization of choline acetyltransferase of common type in the central brain mass of Octopus vulgaris

Directory of Open Access Journals (Sweden)

A. Casini

2012-07-01

Full Text Available Acetylcholine, the first neurotransmitter to be identified in the vertebrate frog, is widely distributed among the animal kingdom. The presence of a large amount of acetylcholine in the nervous system of cephalopods is well known from several biochemical and physiological studies. However, little is known about the precise distribution of cholinergic structures due to a lack of a suitable histochemical technique for detecting acetylcholine. The most reliable method to visualize the cholinergic neurons is the immunohistochemical localization of the enzyme choline acetyltransferase, the synthetic enzyme of acetylcholine. Following our previous study on the distribution patterns of cholinergic neurons in the Octopus vulgaris visual system, using a novel antibody that recognizes choline acetyltransferase of the common type (cChAT, now we extend our investigation on the octopus central brain mass. When applied on sections of octopus central ganglia, immunoreactivity for cChAT was detected in cell bodies of all central brain mass lobes with the notable exception of the subfrontal and subvertical lobes. Positive varicosed nerves fibers where observed in the neuropil of all central brain mass lobes.

Immunolocalization of choline acetyltransferase of common type in the central brain mass of Octopus vulgaris.

Science.gov (United States)

Casini, A; Vaccaro, R; D'Este, L; Sakaue, Y; Bellier, J P; Kimura, H; Renda, T G

2012-07-19

Acetylcholine, the first neurotransmitter to be identified in the vertebrate frog, is widely distributed among the animal kingdom. The presence of a large amount of acetylcholine in the nervous system of cephalopods is well known from several biochemical and physiological studies. However, little is known about the precise distribution of cholinergic structures due to a lack of a suitable histochemical technique for detecting acetylcholine. The most reliable method to visualize the cholinergic neurons is the immunohistochemical localization of the enzyme choline acetyltransferase, the synthetic enzyme of acetylcholine. Following our previous study on the distribution patterns of cholinergic neurons in the Octopus vulgaris visual system, using a novel antibody that recognizes choline acetyltransferase of the common type (cChAT), now we extend our investigation on the octopus central brain mass. When applied on sections of octopus central ganglia, immunoreactivity for cChAT was detected in cell bodies of all central brain mass lobes with the notable exception of the subfrontal and subvertical lobes. Positive varicosed nerves fibers where observed in the neuropil of all central brain mass lobes.

Electrochemical synthesis of nanosized TiO2 nanopowder involving choline chloride based ionic liquids

International Nuclear Information System (INIS)

Anicai, Liana; Petica, Aurora; Patroi, Delia; Marinescu, Virgil; Prioteasa, Paula; Costovici, Stefania

2015-01-01

Highlights: • TiO 2 nanopowder electrochemically prepared using choline chloride based ionic liquids. • The new proposed method allowed high anodic synthesis efficiencies of minimum 92%. • High surface area of the electrochemically synthesized titania nanopowders. • Enhanced photocatalytic activity. - Abstract: The paper presents some experimental results regarding the electrochemical synthesis of TiO 2 nanopowders through anodic dissolution of Ti metal in choline chloride based eutectic mixtures (DES). A detailed characterization of the obtained titania has been performed, using various techniques, including XRD, Raman spectroscopy, XPS, SEM associated with EDX analysis, BET and UV–vis diffuse reflectance spectra. The anodic behavior of Ti electrode in DES has been also investigated. The photoreactivity of the synthesized materials was evaluated for the degradation of Orange II dye under UV (λ = 365 nm) and visible light irradiation. An anodic synthesis efficiency of minimum 92% has been determined. The as-synthesized TiO 2 showed amorphous structure and a calcination post-treatment at temperatures between 400 and 600 °C yielded anatase. The anodically obtained nanocrystalline oxides have crystallite sizes of 8–18 nm, a high surface area and enhanced photocatalytic effect

Dietary choline supplementation in adult rats improves performance on a test of recognition memory.

Science.gov (United States)

Moreno, Hayarelis; Hall, Geoffrey; Gallo, Milagros; de Brugada, Isabel

2018-04-22

In two experiments adult rats (aged at least 6 months at the start of the procedure) received a diet enriched with added choline for a period of 10 weeks; control subjects were maintained on a standard diet during this time. All rats then underwent the spontaneous object recognition (SOR) procedure in which they were exposed to a pair of objects and then tested, after a retention interval, to a display with one object changed. Exploration of the changed object indicates retention and use of information acquired during the exposure phase. All subjects showed retention with a 24-h interval (Experiments 1 and 2) and when retested after a further 24 h (Experiment 1). But when tested for the first time after a 48-h interval (Experiment 2), control subjects showed no evidence of retention, exploring both objects equally, whereas those given the dietary supplement continued to show a preference for the changed object. This supports the conclusion that dietary choline supplementation can enhance performance on a task regarded as a test of declarative memory, and will do so even when the supplementations is given in adulthood. Copyright © 2018 Elsevier B.V. All rights reserved.

Biosynthesis of the Common Polysaccharide Antigen of Pseudomonas aeruginosa PAO1: Characterization and Role of GDP-D-Rhamnose:GlcNAc/GalNAc-Diphosphate-Lipid α1,3-D-Rhamnosyltransferase WbpZ.

Science.gov (United States)

Wang, Shuo; Hao, Youai; Lam, Joseph S; Vlahakis, Jason Z; Szarek, Walter A; Vinnikova, Anna; Veselovsky, Vladimir V; Brockhausen, Inka

2015-06-15

The opportunistic pathogen Pseudomonas aeruginosa produces two major cell surface lipopolysaccharides, characterized by distinct O antigens, called common polysaccharide antigen (CPA) and O-specific antigen (OSA). CPA contains a polymer of D-rhamnose (D-Rha) in α1-2 and α1-3 linkages. Three putative glycosyltransferase genes, wbpX, wbpY, and wbpZ, are part of the CPA biosynthesis cluster. To characterize the enzymatic function of the wbpZ gene product, we chemically synthesized the donor substrate GDP-D-Rha and enzymatically synthesized GDP-D-[(3)H]Rha. Using nuclear magnetic resonance (NMR) spectroscopy, we showed that WbpZ transferred one D-Rha residue from GDP-D-Rha in α1-3 linkage to both GlcNAc- and GalNAc-diphosphate-lipid acceptor substrates. WbpZ is also capable of transferring D-mannose (D-Man) to these acceptors. Therefore, WbpZ has a relaxed specificity with respect to both acceptor and donor substrates. The diphosphate group of the acceptor, however, is required for activity. WbpZ does not require divalent metal ion for activity and exhibits an unusually high pH optimum of 9. WbpZ from PAO1 is therefore a GDP-D-Rha:GlcNAc/GalNAc-diphosphate-lipid α1,3-D-rhamnosyltransferase that has significant activity of GDP-D-Man:GlcNAc/GalNAc-diphosphate-lipid α1,3-D-mannosyltransferase. We used site-directed mutagenesis to replace the Asp residues of the two DXD motifs with Ala. Neither of the mutant constructs of wbpZ (D172A or D254A) could be used to rescue CPA biosynthesis in the ΔwbpZ knockout mutant in a complementation assay. This suggested that D172 and D254 are essential for WbpZ function. This work is the first detailed characterization study of a D-Rha-transferase and a critical step in the development of CPA synthesis inhibitors. This is the first characterization of a D-rhamnosyltransferase and shows that it is essential in Pseudomonas aeruginosa for the synthesis of the common polysaccharide antigen. Copyright © 2015, American Society for

No up-regulation of the phosphatidylethanolamine N-methyltransferase pathway and choline production by sex hormones in cats

NARCIS (Netherlands)

Valtolina, Chiara; Vaandrager, Arie B; Favier, Robert P; Robben, Joris H; Tuohetahuntila, Maidina; Kummeling, Anne; Jeusette, Isabelle; Rothuizen, Jan

2015-01-01

BACKGROUND: Feline hepatic lipidosis (FHL) is a common cholestatic disease affecting cats of any breed, age and sex. Both choline deficiency and low hepatic phosphatidylethanolamine N-methyltransferase (PEMT) activity are associated with hepatic lipidosis (HL) in humans, mice and rats. The PEMT

Fully automated preparation of [11C]choline and [18F]fluoromethylcholine using TracerLab synthesis modules and facilitated quality control using analytical HPLC

International Nuclear Information System (INIS)

Shao Xia; Hockley, Brian G.; Hoareau, Raphael; Schnau, Paul L.; Scott, Peter J.H.

2011-01-01

Modifications of a GE TracerLab FX C-Pro , which can be implemented for solid-phase [ 11 C]methylation are described. The simplified procedure for synthesis of [ 11 C]choline uses a single Sep-Pak CM-Light cation-exchange cartridge for both solid-supported reaction and purification. Compared with the commonly used two Sep-Pak method, the low back-pressure of this Sep-Pak enables efficient and reliable production of [ 11 C]choline using a TracerLab FX C-Pro without requirement for any gas pressure adjustment. Typical radiochemical yields (RCY) are >60%, radiochemical purity (RCP) is 99.9% and levels of residual precursor in the final product, which may inhibit the uptake of [ 11 C]choline, are reduced to 1 μg/mL. Similarly, modification of a GE TracerLab FX FN is reported which enables gas-phase production of [ 18 F]fluoromethylcholine, suitable for pre-clinical use, (in 4-6% RCY and >99.7% RCP) using a related Sep-Pak method. These modifications can be utilized for solid-phase [ 11 C]methylation and [ 18 F]fluoromethylation of other radiotracers, and allow straightforward switching to other module configurations for solution-phase radiochemistry or loop chemistry. In addition, we report a convenient HPLC ion chromatography method, which can monitor residual precursor and the radiochemical purity of product at the same time, providing highly efficient quality control for routine clinical application. The reported HPLC method is appropriate for analysis of doses of both [ 11 C]choline and [ 18 F]fluoromethylcholine, and eliminates the need for a GC method to determine residual precursor levels. -- Graphical abstract: Simplified procedures for the automated synthesis of [ 11 C]choline and [ 18 F]fluoromethylcholine using TracerLab FX C-Pro and TracerLab FX FN synthesis modules are presented. In addition, we report a convenient HPLC ion chromatography method, which can monitor residual precursor and radiochemical purity of the product at the same time. Display Omitted

Activation-induced cytidine deaminase (AID) is localized to subnuclear domains enriched in splicing factors

Energy Technology Data Exchange (ETDEWEB)

Hu, Yi, E-mail: yihooyi@gmail.com; Ericsson, Ida, E-mail: ida.ericsson@ntnu.no; Doseth, Berit, E-mail: berit.doseth@ntnu.no; Liabakk, Nina B., E-mail: nina.beate.liabakk@ntnu.no; Krokan, Hans E., E-mail: hans.krokan@ntnu.no; Kavli, Bodil, E-mail: bodil.kavli@ntnu.no

2014-03-10

Activation-induced cytidine deaminase (AID) is the mutator enzyme in adaptive immunity. AID initiates the antibody diversification processes in activated B cells by deaminating cytosine to uracil in immunoglobulin genes. To some extent other genes are also targeted, which may lead to genome instability and B cell malignancy. Thus, it is crucial to understand its targeting and regulation mechanisms. AID is regulated at several levels including subcellular compartmentalization. However, the complex nuclear distribution and trafficking of AID has not been studied in detail previously. In this work, we examined the subnuclear localization of AID and its interaction partner CTNNBL1 and found that they associate with spliceosome-associated structures including Cajal bodies and nuclear speckles. Moreover, protein kinase A (PKA), which activates AID by phosphorylation at Ser38, is present together with AID in nuclear speckles. Importantly, we demonstrate that AID physically associates with the major spliceosome subunits (small nuclear ribonucleoproteins, snRNPs), as well as other essential splicing components, in addition to the transcription machinery. Based on our findings and the literature, we suggest a transcription-coupled splicing-associated model for AID targeting and activation. - Highlights: • AID and its interaction partner CTNNBL1 localize to Cajal bodies and nuclear speckles. • AID associates with its activating kinase PKA in nuclear speckles. • AID is linked to the splicing machinery in switching B-cells. • Our findings suggest a transcription-coupled splicing associated mechanism for AID targeting and activation.

Experience in using ceretone (choline alfoscerate in brain concussion

Directory of Open Access Journals (Sweden)

N G Voropay

2010-01-01

Full Text Available Nootropics are used to treat patients who have sustained concussion of the brain and complain of reductions in memory and working capacity, as well as emotional disorders. The efficacy of ceretone® (choline alfoscerate was studied in 76 patients (45 men and 31 women whose age was 21-56 years who had sustained brain concussion and had complaints of headache, easy fatigability, nocturnal sleep disorders, daytime sleepiness, anxiety, and bad mood. Thirty-nine patients received intravenous ceretone® in a dose of 1000 mg/day for 10 days; the other 37 patients formed a control group. A one-year follow-up indicated that ceretone® had a positive effect on health, autonomic, and emotional status and working capacity.

A robust quantitative solid phase immunoassay for the acute phase protein C-reactive protein (CRP) based on cytidine 5 '-diphosphocholine coupled dendrimers

DEFF Research Database (Denmark)

Heegaard, Peter M. H.; Pedersen, H. G.; Jensen, A. L.

2009-01-01

C-reactive protein (CRP) is an important acute phase protein, being used as a sensitive indicator of inflammation and infection and is also associated with the risk of cardiovascular problems. The present paper describes a robust and sensitive ELISA for CRP, based on the affinity of CRP for phosp......C-reactive protein (CRP) is an important acute phase protein, being used as a sensitive indicator of inflammation and infection and is also associated with the risk of cardiovascular problems. The present paper describes a robust and sensitive ELISA for CRP, based on the affinity of CRP...... was applied to determination of pig and human CRP using commercially available antibodies against human CRP. The assay was shown to be more sensitive than previously published immunoassays employing albumin-coupled cytidine diphosphocholine. The coating was stable for at least 30 days at room temperature...

{sup 11}C-Choline PET/CT in castration-resistant prostate cancer patients treated with docetaxel

Energy Technology Data Exchange (ETDEWEB)

Ceci, Francesco [University of Bologna, Service of Nuclear Medicine, S. Orsola-Malpighi Hospital, Bologna (Italy); Azienda Ospedaliero-Universitaria di Bologna, Policlinico S. Orsola-Malpighi, UO Medicina Nucleare PAD. 30, Bologna (Italy); Castellucci, Paolo; Graziani, Tiziano; Renzi, Riccardo; Fanti, Stefano [University of Bologna, Service of Nuclear Medicine, S. Orsola-Malpighi Hospital, Bologna (Italy); Schiavina, Riccardo; Borghesi, Marco; Brunocilla, Eugenio [University of Bologna, Department of Urology, S. Orsola-Malpighi Hospital, Bologna (Italy); Di Tullio, Piergiorgio; Ardizzoni, Andrea [University of Bologna, Department of Oncology, S. Orsola-Malpighi Hospital, Bologna (Italy)

2016-01-15

To investigate the role of {sup 11}C-choline PET/CT for evaluating the response to treatment in patients with metastatic castration-resistant prostate cancer (mCRPC) treated with docetaxel in comparison with PSA response. Inclusion criteria were (a) proven mCRPC, (b) docetaxel as first line of chemotherapy (docetaxel 75 mg/m{sup 2} + prednisone 5 mg), and (c) {sup 11}C-choline PET/CT and PSA values assessed before and after docetaxel administration. A total of 61 patients were retrospectively enrolled (mean age 68.9 years, range 57 - 84 years). {sup 11}C-Choline PET/CT was performed at baseline before docetaxel treatment (PET1) and after the end of treatment (PET2). PSA values were measured before treatment (PSA1) and after treatment (PSA2). PET2 was reported as complete response (CR), partial response (PR) or stable disease (SD). Progressive disease (PD) was considered if a new lesion was seen. PSA trend was calculated from the change in absolute values between PSA1 and PSA2. A decrease of ≥50 % between PSA1 and PSA2 was considered a PSA response. Clinical, radiological and laboratory follow-up ranged from 6 to 53 months (mean 13.5 months). Of the 61 patients, 40 (65.5 %) showed PD on PET2, 13 (21.3 %) showed SD, 2 (3.4 %) showed PR, and 6 (9.8 %) showed CR. An increasing PSA trend was seen in 29 patients (47.5 %) and a decreasing PSA trend in 32 patients (52.5 %). A PSA response of ≥50 % was seen in 25 patients (41 %). Radiological PD was seen in 23 of the 29 patients (79.3 %) with an increasing PSA trend, in 16 of the 32 patients (50 %) with a decreasing PSA trend, and in 11 of the 25 patients (44 %) with a PSA response of ≥50 %. In the multivariate statistical analysis, the presence of more than ten bone lesions detected on PET1 was significantly associated with an increased probability of PD on PET2. No association was observed between PSA level and PD on PET2. Our results suggest that an increasing PSA trend measured after docetaxel treatment could be

Tricistronic operon expression of the genes gcaD (tms), which encodes N-acetylglucosamine 1-phosphate uridyltransferase, prs, which encodes phosphoribosyl diphosphate synthetase, and ctc in vegetative cells of Bacillus subtilis

DEFF Research Database (Denmark)

Hilden, Ida; Krath, Britta N.; Hove-Jensen, Bjarne

1995-01-01

The gcaD, prs, and ctc genes were shown to be organized as a tricistronic operon. The transcription of the prs gene, measured as phosphoribosyl diphosphate synthetase activity, and of the ctc gene, measured as β-galactosidase activity specified by a ctc-lacZ protein fusion, were dependent...

A study of 11C-acetate production using 11C-choline commercial module

International Nuclear Information System (INIS)

Zhang Jinming; Tian Jiahe; Yao Shulin; Chen Yan

2008-01-01

Objective: 11 C-acetate is a useful PET tracer in evaluating myocardial metabolism but more interest has been focused on its application in tumor detection in recent years, especially hepatocellular carcinoma (HCC). This study was designed to evaluate the laboratory, preparation of 11 C-acetate with a modified 11 C-choline commercial module and to investigate its biodistribution in tumor (lung adenocarcinoma)-bearing mice as well as its potential as a tumor imaging agent. Methods: 11 C-acetate was synthesized with a modified 11 C choline module: Methyl magnesium bromide Grignard (0.1 ml of 1.5 mol/L) was load- ed to a Teflon loop before 11 CO 2 was recovered from the target. Cartier acetate solution (2 ml of 1 mmol/L) was pushed through the loop, SPE cartridges (mixed AG50 and IC-Ag) and then the QMA. The loop and cartridges were then rinsed with water. The product 11 C-acetate was then washed out from QMA with 0.9% NaCl solution into a collection vial containing diluted HCl. 11 C-carbonate was removed by nitrogen bubbling for 2 min. After neutralization with trisodium citrate, the injectable 11 C-acetate solution was obtained. The tumor-bearing mice were sacrificed. The percentage activity of injected dose per gram of tissue (% ID/g) for tumor and other tissues were calculated. One patient with known diagnosis of moderately differentiated HCC was injected with 11 C-acetate and imaged by PET/CT, followed by 18 F-fluorodeoxyglucose (FDG). Results: The synthesis yield of 11 C-acetate was (60.5 ± 8.7)% (decay conected, n=10); the radio-chemistry purity was > 98% and the synthesis time was 10 min from 11 CO 2 to 11 C-acetate. The radioactivity ratio for tumor/muscle was 1.76 at 30 min. A patient with known HCC showed positive 11 C-acetate accumulation in the tumor but was negative in 18 F-FDG. Conclusion: The synthesis of 11 C-acetate by modification of an 11 C-choline commercial module was feasible and it could be achieved with high yield, high radiochemical purity

Determination of betaine, l-carnitine, and choline in human urine using a self-packed column and column-switching ion chromatography with nonsuppressed conductivity detection.

Science.gov (United States)

Wei, Dan; Liu, Junwei; Guo, Ming; Zhu, Yan

2017-11-01

A simple method for the determination of betaine, l-carnitine, and choline in human urine was developed based on column-switching ion chromatography coupled with nonsuppressed conductivity detection by using a self-packed column. A pretreatment column (50 mm × 4.6 mm, id) packed with poly(glycidyl methacrylate-divinylbenzene) microspheres was used for the extraction and cleanup of analytes. Chromatographic separation was achieved within 10 min on a cationic exchange column (150 mm × 4.6 mm, id) using maleic anhydride modified poly(glycidyl methacrylate-divinylbenzene) as the particles for packing. The detection was performed by ion chromatography with nonsuppressed conductivity detection. Parameters including column-switching time, eluent type, flow rates of eluent, and interfering effects were optimized. Linearity (r 2 ≥ 0.99) was obtained for the concentration range of 0.50-100, 0.75-100, and 0.25-100 μg/mL for betaine, l-carnitine, and choline, respectively. Detection limits were 0.12, 0.20, and 0.05 μg/mL for betaine, l-carnitine, and choline, respectively. The intra- and interday accuracy and precision for all quality controls were within ±10.11%. Satisfactory recovery was observed between 92.5 and 105.0%. The validated method was successfully applied for the determination of betaine, l-carnitine, and choline in urine samples from healthy people. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Prospective Comparison of F-18 Choline PET/CT Scan Versus Axial MRI for Detecting Bone Metastasis in Biochemically Relapsed Prostate Cancer Patients

Directory of Open Access Journals (Sweden)

Wouter Huysse

2017-10-01

Full Text Available We compared fluor-18 choline positron emission tomography/computed tomography (PET/CT and axial skeleton magnetic resonance imaging (MRI prospectively obtained for the detection of bone metastases in non-castrated patients with biochemically recurrent prostate cancer following primary treatment. PET/CT was performed 45 min post-injection of 3–4 MBq/kg F-18 methyl choline. MRI included T1- and fluid sensitive T2-weighted images of the spine and pelvis. Readers were initially blinded from other results and all scans underwent independent double reading. The best valuable comparator (BVC defined the metastatic status. On the basis of the BVC, 15 out of 64 patients presented with 24 bone metastases. On a patient level, the sensitivity and specificity of MRI and PET were not significantly different. On a lesion level, the sensitivity of MRI was significantly better compared to PET, and the specificity did not differ significantly. In conclusion, axial MRI is an interesting screening tool for the detection of bone metastases because of its low probability of false negative results. However, F-18 choline PET is a valuable addition as it can overrule false positive MRI results and detect non-axial metastases.

Synthesis, hybridization characteristics, and fluorescence properties of oligonucleotides modified with nucleobase-functionalized locked nucleic acid adenosine and cytidine monomers.

Science.gov (United States)

Kaura, Mamta; Kumar, Pawan; Hrdlicka, Patrick J

2014-07-03

Conformationally restricted nucleotides such as locked nucleic acid (LNA) are very popular as affinity-, specificity-, and stability-enhancing modifications in oligonucleotide chemistry to produce probes for nucleic acid targeting applications in molecular biology, biotechnology, and medicinal chemistry. Considerable efforts have been devoted in recent years to optimize the biophysical properties of LNA through additional modification of the sugar skeleton. We recently introduced C5-functionalization of LNA uridines as an alternative and synthetically more straightforward approach to improve the biophysical properties of LNA. In the present work, we set out to test the generality of this concept by studying the characteristics of oligonucleotides modified with four different C5-functionalized LNA cytidine and C8-functionalized LNA adenosine monomers. The results strongly suggest that C5-functionalization of LNA pyrimidines is indeed a viable approach for improving the binding affinity, target specificity, and/or enzymatic stability of LNA-modified ONs, whereas C8-functionalization of LNA adenosines is detrimental to binding affinity and specificity. These insights will impact the future design of conformationally restricted nucleotides for nucleic acid targeting applications.

Crystal structure of APOBEC3A bound to single-stranded DNA reveals structural basis for cytidine deamination and specificity.

Science.gov (United States)

Kouno, Takahide; Silvas, Tania V; Hilbert, Brendan J; Shandilya, Shivender M D; Bohn, Markus F; Kelch, Brian A; Royer, William E; Somasundaran, Mohan; Kurt Yilmaz, Nese; Matsuo, Hiroshi; Schiffer, Celia A

2017-04-28

Nucleic acid editing enzymes are essential components of the immune system that lethally mutate viral pathogens and somatically mutate immunoglobulins, and contribute to the diversification and lethality of cancers. Among these enzymes are the seven human APOBEC3 deoxycytidine deaminases, each with unique target sequence specificity and subcellular localization. While the enzymology and biological consequences have been extensively studied, the mechanism by which APOBEC3s recognize and edit DNA remains elusive. Here we present the crystal structure of a complex of a cytidine deaminase with ssDNA bound in the active site at 2.2 Å. This structure not only visualizes the active site poised for catalysis of APOBEC3A, but pinpoints the residues that confer specificity towards CC/TC motifs. The APOBEC3A-ssDNA complex defines the 5'-3' directionality and subtle conformational changes that clench the ssDNA within the binding groove, revealing the architecture and mechanism of ssDNA recognition that is likely conserved among all polynucleotide deaminases, thereby opening the door for the design of mechanistic-based therapeutics.

Solubility of disodium cytidine 5′-monophosphate in different binary mixtures from 288.15 K to 313.15 K

International Nuclear Information System (INIS)

Yu, Jin; Ma, Tianle; Li, An; Chen, Xiaochun; Chen, Yong; Xie, Jingjing; Wu, Jinglan; Ying, Hanjie

2013-01-01

Highlights: • Solubility of 5′-CMPNa 2 in different systems was measured the first time. • Experimental data were correlated by CNIBS/Redlich–Kister model and Apelblat model. • Good agreement has been observed between the calculated and the experimental data. • Enthalpy and entropy were calculated by the van’t Hoff equation and Gibbs equation. - Abstract: The solubility of disodium cytidine 5′-monophosphate (5′-CMPNa 2 ) in methanol + water and ethanol + water binary mixtures was measured experimentally at the temperatures ranging from 288.15 to 313.15 K. The results showed that the solubility of 5′-CMPNa 2 increased with the increasing of temperature and the mole fraction of water in different binary mixtures. The (CNIBS)/Redlich–Kister model and the semi-empirical Apelblat model were applied for the prediction of the experimental data. Both models could give satisfactory simulation results. In addition, the thermodynamic properties of the dissolution process such as Gibbs energy, enthalpy, and entropy were calculated using the van’t Hoff equation and the Gibbs equation. The results indicated that the dissolution process was endothermic

Protein preparation, crystallization and preliminary X-ray analysis of Trypanosoma cruzi nucleoside diphosphate kinase 1

International Nuclear Information System (INIS)

Gómez Barroso, J. A.; Pereira, H.; Miranda, M.; Pereira, C.; Garratt, R. C.; Aguilar, C. F.

2010-01-01

T. cruzi TcNDPK1 was overexpressed in Escherichia coli as an N-terminally poly-His-tagged fusion protein and crystallized. The flagellated protozoan parasite Trypanosoma cruzi is the aetiological agent of Chagas disease. Nucleoside diphosphate kinases (NDPKs) are enzymes that are involved in energy management and nucleoside balance in the cell. T. cruzi TcNDPK1, a canonical isoform, was overexpressed in Escherichia coli as an N-terminally poly-His-tagged fusion protein and crystallized. Crystals grew after 72 h in 0.2 M MgCl 2 , 20% PEG 3350. Data were collected to 3.5 Å resolution using synchrotron X-ray radiation at the National Synchrotron Light Laboratory (Campinas, Brazil). The crystals belonged to the trigonal space group P3, with unit-cell parameters a = b = 127.84, c = 275.49 Å. Structure determination is under way and will provide relevant information that may lead to the first step in rational drug design for the treatment of Chagas disease

Electron attachment to DNA single strands: gas phase and aqueous solution.

Science.gov (United States)

Gu, Jiande; Xie, Yaoming; Schaefer, Henry F

2007-01-01

The 2'-deoxyguanosine-3',5'-diphosphate, 2'-deoxyadenosine-3',5'-diphosphate, 2'-deoxycytidine-3',5'-diphosphate and 2'-deoxythymidine-3',5'-diphosphate systems are the smallest units of a DNA single strand. Exploring these comprehensive subunits with reliable density functional methods enables one to approach reasonable predictions of the properties of DNA single strands. With these models, DNA single strands are found to have a strong tendency to capture low-energy electrons. The vertical attachment energies (VEAs) predicted for 3',5'-dTDP (0.17 eV) and 3',5'-dGDP (0.14 eV) indicate that both the thymine-rich and the guanine-rich DNA single strands have the ability to capture electrons. The adiabatic electron affinities (AEAs) of the nucleotides considered here range from 0.22 to 0.52 eV and follow the order 3',5'-dTDP > 3',5'-dCDP > 3',5'-dGDP > 3',5'-dADP. A substantial increase in the AEA is observed compared to that of the corresponding nucleic acid bases and the corresponding nucleosides. Furthermore, aqueous solution simulations dramatically increase the electron attracting properties of the DNA single strands. The present investigation illustrates that in the gas phase, the excess electron is situated both on the nucleobase and on the phosphate moiety for DNA single strands. However, the distribution of the extra negative charge is uneven. The attached electron favors the base moiety for the pyrimidine, while it prefers the 3'-phosphate subunit for the purine DNA single strands. In contrast, the attached electron is tightly bound to the base fragment for the cytidine, thymidine and adenosine nucleotides, while it almost exclusively resides in the vicinity of the 3'-phosphate group for the guanosine nucleotides due to the solvent effects. The comparatively low vertical detachment energies (VDEs) predicted for 3',5'-dADP(-) (0.26 eV) and 3',5'-dGDP(-) (0.32 eV) indicate that electron detachment might compete with reactions having high activation barriers

Role of 11C-choline positron emission tomography/computed tomography in evaluating patients affected by prostate cancer with suspected relapse due to prostate-specific antigen elevation

International Nuclear Information System (INIS)

Bertagna, F.; Bosio, G.; Abuhilal, M.

2011-01-01

The aim of this study was to evaluate the accuracy of 11 C-choline positron emission tomography/computed tomography (PET/CT) in restaging patients affected by prostate cancer and suspected relapse due to prostate-specific antigen (PSA) increase. We also aimed to determine a PSA cutoff that is most suited to the study in terms of best compromise between sensitivity and specificity. Secondary endpoints were a comparison between 11 C-choline PET/CT and histological results, clinical findings, and radiological imaging (CT and magnetic resonance imaging). We retrospectively evaluated 210 patients (median±standard deviation (SD) age 70±7 years) affected by prostate cancer who underwent 11 C-choline PET/CT. 11 C-choline PET/CT imaging was positive in 116 (55.2%) patients and negative in 94 (44.8%). Receiver operating characteristic (ROC) analysis showed that the highest accuracy (sensitivity 76.8%, specificity 92.5%) for the whole population was achieved when the PSA level of 1.26 ng/ml level was used as the cutoff value for interpreting the results (P=0.0001 and the area under the ROC curve area under the curve (AUC)=0.897). For patients treated with surgery or surgery plus radiotherapy the cutoff was 0.81 ng/ml (sensitivity 73.2%, specificity 86.1%). For patients treated with radiotherapy alone, the cutoff was 2.0 ng/ml (sensitivity 81.8%, specificity 92.9%). Our results indicate that 11 C-choline PET/CT is a useful diagnostic tool in patients affected by prostate cancer and a relapsed PSA level. The highest accuracy for all patients is obtained with a PSA cutoff level of 1.26 ng/ml, above which the imaging study is performed (0.81 ng/ml for patients treated with surgery or surgery plus radiotherapy and 2.0 ng/ml for patients treated with radiotherapy alone). (author)

The defective phosphoribosyl diphosphate synthase in a temperature-sensitive prs-2 mutant of Escherichia coli is compensated by increased enzyme synthesis

DEFF Research Database (Denmark)

Post, David A.; Switzer, Robert L.; Hove-Jensen, Bjarne

1996-01-01

An Escherichia coli strain which is temperature-sensitive for growth due to a mutation (prs-2) causing a defective phosphoribosyl diphosphate (PRPP) synthase has been characterized. The temperature-sensitive mutation was mapped to a 276 bp HindIII-BssHII DNA fragment located within the open reading...... temperature shift to 42 degrees C. The other mutation was a C -> T transition located 39 bp upstream of the G -> A mutation, i.e. outside the coding sequence and close to the Shine-Dalgarno sequence. Cells harbouring only the C -> T mutation in a plasmid contained approximately three times as much PRPP...

Electrochemical synthesis of nanosized TiO{sub 2} nanopowder involving choline chloride based ionic liquids

Energy Technology Data Exchange (ETDEWEB)

Anicai, Liana, E-mail: lanicai@itcnet.ro [POLITEHNICA University of Bucharest, Center of Surface Science and Nanotechnology, Splaiul Independentei 313, Bucharest, 060042 (Romania); Petica, Aurora [Leather and Footwear Research Institute (ICPI), Ion Minulescu 93, Bucharest, 031215 (Romania); Patroi, Delia; Marinescu, Virgil; Prioteasa, Paula [INCDIE ICPE-Advanced Research, Splaiul Unirii 313, Bucharest (Romania); Costovici, Stefania [POLITEHNICA University of Bucharest, Center of Surface Science and Nanotechnology, Splaiul Independentei 313, Bucharest, 060042 (Romania)

2015-09-15

Highlights: • TiO{sub 2} nanopowder electrochemically prepared using choline chloride based ionic liquids. • The new proposed method allowed high anodic synthesis efficiencies of minimum 92%. • High surface area of the electrochemically synthesized titania nanopowders. • Enhanced photocatalytic activity. - Abstract: The paper presents some experimental results regarding the electrochemical synthesis of TiO{sub 2} nanopowders through anodic dissolution of Ti metal in choline chloride based eutectic mixtures (DES). A detailed characterization of the obtained titania has been performed, using various techniques, including XRD, Raman spectroscopy, XPS, SEM associated with EDX analysis, BET and UV–vis diffuse reflectance spectra. The anodic behavior of Ti electrode in DES has been also investigated. The photoreactivity of the synthesized materials was evaluated for the degradation of Orange II dye under UV (λ = 365 nm) and visible light irradiation. An anodic synthesis efficiency of minimum 92% has been determined. The as-synthesized TiO{sub 2} showed amorphous structure and a calcination post-treatment at temperatures between 400 and 600 °C yielded anatase. The anodically obtained nanocrystalline oxides have crystallite sizes of 8–18 nm, a high surface area and enhanced photocatalytic effect.

A modified choline-deficient, ethionine-supplemented diet reduces morbidity and retains a liver progenitor cell response in mice

Directory of Open Access Journals (Sweden)

Adam M. Passman

2015-12-01

Full Text Available The choline-deficient, ethionine-supplemented (CDE dietary model induces chronic liver damage, and stimulates liver progenitor cell (LPC-mediated repair. Long-term CDE administration leads to hepatocellular carcinoma in rodents and lineage-tracing studies show that LPCs differentiate into functional hepatocytes in this model. The CDE diet was first modified for mice by our laboratory by separately administering choline-deficient chow and ethionine in the drinking water (CD+E diet. Although this CD+E diet is widely used, concerns with variability in weight loss, morbidity, mortality and LPC response have been raised by researchers who have adopted this model. We propose that these inconsistencies are due to differential consumption of chow and ethionine in the drinking water, and that incorporating ethionine in the choline-deficient chow, and altering the strength, will achieve better outcomes. Therefore, C57Bl/6 mice, 5 and 6 weeks of age, were fed an all-inclusive CDE diet of various strengths (67% to 100% for 3 weeks. The LPC response was quantitated and cell lines were derived. We found that animal survival, LPC response and liver damage are correlated with CDE diet strength. The 67% and 75% CDE diet administered to mice older than 5 weeks and greater than 18 g provides a consistent and acceptable level of animal welfare and induces a substantial LPC response, permitting their isolation and establishment of cell lines. This study shows that an all-inclusive CDE diet for mice reproducibly induces an LPC response conducive to in vivo studies and isolation, whilst minimizing morbidity and mortality.

PET/CT with {sup 11}C-choline for evaluation of prostate cancer patients with biochemical recurrence: meta-analysis and critical review of available data

Energy Technology Data Exchange (ETDEWEB)

Fanti, Stefano; Castellucci, Paolo [S. Orsola-Malpighi University Hospital, Department of Nuclear Medicine, Bologna (Italy); Minozzi, Silvia [Lazio Regional Health Service, Cochrane Review Group on Drugs and Alcohol, Department of Epidemiology, Rome (Italy); Balduzzi, Sara [University of Modena and Reggio Emilia, Department of Diagnostic Medicine, Clinical and Public Health, Modena (Italy); Herrmann, Ken [David Geffen School of Medicine at UCLA, Department of Molecular and Medical Pharmacology, Los Angeles, CA (United States); University Hospital Wuerzburg, Department of Nuclear Medicine, Wuerzburg (Germany); Krause, Bernd Joachim [Universitaetsmedizin Rostock, Department of Nuclear Medicine, Rostock (Germany); Oyen, Wim [Radboud University Medical Center, Department of Radiology and Nuclear Medicine, Nijmegen (Netherlands); Chiti, Arturo [Humanitas Research Hospital, Nuclear Medicine, Rozzano, Milano (Italy); Humanitas University, Rozzano, Milano (Italy)

2016-01-15

For the last decade PET and PET/CT with {sup 11}C-choline have been proposed for the evaluation of prostate cancer (PC), but the diagnostic performance of {sup 11}C-choline PET/CT is still a matter of debate. We performed a comprehensive review of the most important clinical application of {sup 11}C-choline PET, restaging of patients with biochemical relapse, following a rigorous methodological approach and including assessment of the risk of bias. We conducted a systematic review and meta-analysis of the literature assessing {sup 11}C-choline PET/CT for its accuracy in the diagnosis and ability to detect the site of recurrence of PC in the restaging of patients with biochemical recurrence after initial treatment with curative intent. We performed a comprehensive literature search of PubMed and the Cochrane Library to determine the accuracy for the detection of the site of recurrence (prostate bed recurrences, metastatic spread to locoregional pelvic lymph nodes or distant metastases). Only studies with a reference standard (for prostatic bed histopathology, for histopathology or biopsy of distant metastases or a composite reference standard with clinical follow-up of at least 12 months, correlative imaging and clinical data) were included. Overall 425 studies were retrieved, of which 43 were judged as potentially relevant and 29 with 2,686 participants were finally included. Of these 29 studies, 18 reported results for any relapse, All 18 studies, with a total of 2,126 participants, reported detection rates. The pooled rate was 62 % (95 % CI 53 - 71 %). Of the 18 studies, 12 with 1,270 participants reported useful data to derive sensitivity and specificity. The pooled sensitivity was 89 % (95 % CI 83 - 93 %) and the pooled specificity was 89 % (95 % CI 73 - 96 %). Of 11 studies reporting results for local relapse, 9 with 993 participants reported detection rates. The pooled rate was 27 % (95 % CI 16 - 38 %). Six studies with 491 participants reported sensitivity

Simple determination of betaine, l-carnitine and choline in human urine using self-packed column and column-switching ion chromatography with nonsuppressed conductivity detection.

Science.gov (United States)

Wei, Dan; Zhu, Yan; Guo, Ming

2018-02-01

A sequential online extraction, clean-up and separation system for the determination of betaine, l-carnitine and choline in human urine using column-switching ion chromatography with nonsuppressed conductivity detection was developed in this work. A self-packed pretreatment column (50 × 4.6 mm, i.d.) was used for the extraction and clean-up of betaine, l-carnitine and choline. The separation was achieved using self-packed cationic exchange column (150 × 4.6 mm, i.d.), followed by nonsuppressed conductivity detection. Under optimized experimental conditions, the developed method presented good analytical performance, with excellent linearity in the range of 0.60-100 μg mL -1 for betaine, 0.75-100 μg mL -1 for l-carnitine and 0.50-100 μg mL -1 for choline, with all correlation coefficients (R 2 ) >0.99 in urine. The limits of detection were 0.15 μg mL -1 for betaine, 0.20 μg mL -1 for l-carnitine and 0.09 μg mL -1 for choline. The intra- and inter-day accuracy and precision for all quality controls were within ±10.32 and ±9.05%, respectively. Satisfactory recovery was observed between 92.8 and 102.0%. The validated method was successfully applied to the detection of urinary samples from 10 healthy people. The values detected in human urine using the proposed method showed good agreement with the measurement reported previously. Copyright © 2017 John Wiley & Sons, Ltd.

The optimal timing to perform 18F/11C-choline PET/CT in patients with suspicion of relapse of prostate cancer: trigger PSA versus PSA velocity and PSA doubling time.

Science.gov (United States)

Calabria, Ferdinando; Rubello, Domenico; Schillaci, Orazio

2014-12-09

In the present short communication we considered the main publications focused on trigger prostate-specific antigen (PSA) and PSA kinetics that systematically compared 18F to 11C-choline PET/CT in order to establish the optimal time to perform choline PET/CT in relation to the trigger values and velocity, as well as doubling time of PSA serum levels.

Incidental detection of colorectal cancer via 1(8)F-choline PET/CT in a patient with recurrent prostate cancer: usefulness of early images.

Science.gov (United States)

Bagni, Oreste; Filippi, Luca; Schillaci, Orazio

2015-06-01

A 74-year-old man with history of prostate cancer underwent F-choline PET/CT for restaging. Early acquisition of the pelvic region revealed intense uptake in prostate, with infiltration of the posterior wall of the bladder. Furthermore, focal uptake in the thickened anterior wall of the rectum was detected. Whole-body scan at 60 minutes confirmed early findings in pelvis, although the infiltration of the bladder was no more evident due to interference of radioactive urine. Biopsy demonstrated the presence of colorectal carcinoma. The dual-phase protocol resulted in significant clinical impact to clearly characterize focuses of abnormal F-choline uptake in the pelvic region.

Electrodeposition of copper composites from deep eutectic solvents based on choline chloride.

Science.gov (United States)

Abbott, Andrew P; El Ttaib, Khalid; Frisch, Gero; McKenzie, Katy J; Ryder, Karl S

2009-06-07

Here we describe for the first time the electrolytic deposition of copper and copper composites from a solution of the metal chloride salt in either urea-choline chloride, or ethylene glycol-choline chloride based eutectics. We show that the deposition kinetics and thermodynamics are quite unlike those in aqueous solution under comparable conditions and that the copper ion complexation is also different. The mechanism of copper nucleation is studied using chronoamperometry and it is shown that progressive nucleation leads to a bright nano-structured deposit. In contrast, instantaneous nucleation, at lower concentrations of copper ions, leads to a dull deposit. This work also pioneers the use of the electrochemical quartz crystal microbalance (EQCM) to monitor both current efficiency and the inclusion of inert particulates into the copper coatings. This technique allows the first in situ quantification or particulate inclusion. It was found that the composition of composite material was strongly dependent on the amount of species suspended in solution. It was also shown that the majority of material was dragged onto the surface rather than settling on to it. The distribution of the composite material was found to be even throughout the coating. This technology is important because it facilitates deposition of bright copper coatings without co-ligands such as cyanide. The incorporation of micron-sized particulates into ionic liquids has resulted, in one case, in a decrease in viscosity. This observation is both unusual and surprising; we explain this here in terms of an increase in the free volume of the liquid and local solvent perturbation.

Effect of rumen-protected choline supplementation on liver and adipose gene expression during the transition period in dairy cattle

NARCIS (Netherlands)

Goselink, R.M.A.; Baal, van J.; Widjaja, H.C.A.; Dekker, R.A.; Zom, R.L.G.; Veth, M.J.; Vuuren, van A.M.

2013-01-01

We previously reported that supplementation of rumen-protected choline (RPC) reduces the hepatic triacylglycerol concentration in periparturient dairy cows during early lactation. Here, we investigated the effect of RPC on the transcript levels of lipid metabolism-related genes in liver and adipose

The substrate oxidation mechanism of pyranose 2-oxidase and other related enzymes in the glucose-methanol-choline superfamily.

Science.gov (United States)

Wongnate, Thanyaporn; Chaiyen, Pimchai

2013-07-01

Enzymes in the glucose-methanol-choline (GMC) oxidoreductase superfamily catalyze the oxidation of an alcohol moiety to the corresponding aldehyde. In this review, the current understanding of the sugar oxidation mechanism in the reaction of pyranose 2-oxidase (P2O) is highlighted and compared with that of other enzymes in the GMC family for which structural and mechanistic information is available, including glucose oxidase, choline oxidase, cholesterol oxidase, cellobiose dehydrogenase, aryl-alcohol oxidase, and pyridoxine 4-oxidase. Other enzymes in the family that have been newly discovered or for which less information is available are also discussed. A large primary kinetic isotope effect was observed for the flavin reduction when 2-d-D-glucose was used as a substrate, but no solvent kinetic isotope effect was detected for the flavin reduction step. The reaction of P2O is consistent with a hydride transfer mechanism in which there is stepwise formation of d-glucose alkoxide prior to the hydride transfer. Site-directed mutagenesis of P2O and pH-dependence studies indicated that His548 is a catalytic base that facilitates the deprotonation of C2-OH in D-glucose. This finding agrees with the current mechanistic model for aryl-alcohol oxidase, glucose oxidase, cellobiose dehydrogenase, methanol oxidase, and pyridoxine 4-oxidase, but is different from that of cholesterol oxidase and choline oxidase. Although all of the GMC enzymes share similar structural folding and use the hydride transfer mechanism for flavin reduction, they appear to have subtle differences in the fine-tuned details of how they catalyze substrate oxidation. © 2013 The Authors Journal compilation © 2013 FEBS.

A modified choline-deficient, ethionine-supplemented diet reduces morbidity and retains a liver progenitor cell response in mice.

Science.gov (United States)

Passman, Adam M; Strauss, Robyn P; McSpadden, Sarah B; Finch-Edmondson, Megan L; Woo, Ken H; Diepeveen, Luke A; London, Roslyn; Callus, Bernard A; Yeoh, George C

2015-12-01

The choline-deficient, ethionine-supplemented (CDE) dietary model induces chronic liver damage, and stimulates liver progenitor cell (LPC)-mediated repair. Long-term CDE administration leads to hepatocellular carcinoma in rodents and lineage-tracing studies show that LPCs differentiate into functional hepatocytes in this model. The CDE diet was first modified for mice by our laboratory by separately administering choline-deficient chow and ethionine in the drinking water (CD+E diet). Although this CD+E diet is widely used, concerns with variability in weight loss, morbidity, mortality and LPC response have been raised by researchers who have adopted this model. We propose that these inconsistencies are due to differential consumption of chow and ethionine in the drinking water, and that incorporating ethionine in the choline-deficient chow, and altering the strength, will achieve better outcomes. Therefore, C57Bl/6 mice, 5 and 6 weeks of age, were fed an all-inclusive CDE diet of various strengths (67% to 100%) for 3 weeks. The LPC response was quantitated and cell lines were derived. We found that animal survival, LPC response and liver damage are correlated with CDE diet strength. The 67% and 75% CDE diet administered to mice older than 5 weeks and greater than 18 g provides a consistent and acceptable level of animal welfare and induces a substantial LPC response, permitting their isolation and establishment of cell lines. This study shows that an all-inclusive CDE diet for mice reproducibly induces an LPC response conducive to in vivo studies and isolation, whilst minimizing morbidity and mortality. © 2015. Published by The Company of Biologists Ltd.

Supplementation with Folic Acid, but Not Creatine, Increases Plasma Betaine, Decreases Plasma Dimethylglycine, and Prevents a Decrease in Plasma Choline in Arsenic-Exposed Bangladeshi Adults.

Science.gov (United States)

Hall, Megan N; Howe, Caitlin G; Liu, Xinhua; Caudill, Marie A; Malysheva, Olga; Ilievski, Vesna; Lomax-Luu, Angela M; Parvez, Faruque; Siddique, Abu B; Shahriar, Hasan; Uddin, Mohammad N; Islam, Tariqul; Graziano, Joseph H; Gamble, Mary V

2016-05-01

Folic acid (FA) supplementation facilitates urinary excretion of arsenic, a human carcinogen. A better understanding of interactions between one-carbon metabolism intermediates may improve the ability to design nutrition interventions that further facilitate arsenic excretion. The objective was to determine if FA and/or creatine supplementation increase choline and betaine and decrease dimethylglycine (DMG). We conducted a secondary analysis of the Folic Acid and Creatine Trial, a randomized trial in arsenic-exposed Bangladeshi adults (n = 605, aged 24-55 y, 50.3% male) who received arsenic-removal water filters. We examined treatment effects of FA and/or creatine supplementation on plasma choline, betaine, and DMG concentrations, measured by LC-tandem mass spectrometry at baseline and at week 12. Group comparisons were between 1) 400 and 800 μg FA/d (FA400 and FA800, respectively) compared with placebo, 2) creatine (3 g/d) compared with placebo, and 3) creatine plus FA400 compared with FA400. Choline decreased in the placebo group (-6.6%; 95% CI: -10.2%, -2.9%) but did not change in the FA groups (FA400: 2.5%; 95% CI: -0.9%, 6.1%; FA800: 1.4%; 95% CI: -2.5%, 5.5%; P creatine treatment arms and their respective reference groups. Supplementation for 12 wk with FA, but not creatine, increases plasma betaine, decreases plasma DMG, and prevents a decrease in plasma choline in arsenic-exposed Bangladeshi adults. This trial was registered at clinicaltrials.gov as NCT01050556. © 2016 American Society for Nutrition.

Solubility of disodium cytidine 5′-monophosphate in different binary mixtures from 288.15 K to 313.15 K

Energy Technology Data Exchange (ETDEWEB)

Yu, Jin [College of Biotechnology and Pharmaceutical Engineering, Nanjing University of Technology, Nanjing (China); National Engineering Technique Research Center for Biotechnology, Nanjing (China); Ma, Tianle; Li, An [National Engineering Technique Research Center for Biotechnology, Nanjing (China); State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing (China); Chen, Xiaochun; Chen, Yong; Xie, Jingjing [College of Biotechnology and Pharmaceutical Engineering, Nanjing University of Technology, Nanjing (China); National Engineering Technique Research Center for Biotechnology, Nanjing (China); Wu, Jinglan, E-mail: yinghanjie@njut.edu.cn [College of Biotechnology and Pharmaceutical Engineering, Nanjing University of Technology, Nanjing (China); National Engineering Technique Research Center for Biotechnology, Nanjing (China); Ying, Hanjie [College of Biotechnology and Pharmaceutical Engineering, Nanjing University of Technology, Nanjing (China); National Engineering Technique Research Center for Biotechnology, Nanjing (China); State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing (China)

2013-08-10

Highlights: • Solubility of 5′-CMPNa{sub 2} in different systems was measured the first time. • Experimental data were correlated by CNIBS/Redlich–Kister model and Apelblat model. • Good agreement has been observed between the calculated and the experimental data. • Enthalpy and entropy were calculated by the van’t Hoff equation and Gibbs equation. - Abstract: The solubility of disodium cytidine 5′-monophosphate (5′-CMPNa{sub 2}) in methanol + water and ethanol + water binary mixtures was measured experimentally at the temperatures ranging from 288.15 to 313.15 K. The results showed that the solubility of 5′-CMPNa{sub 2} increased with the increasing of temperature and the mole fraction of water in different binary mixtures. The (CNIBS)/Redlich–Kister model and the semi-empirical Apelblat model were applied for the prediction of the experimental data. Both models could give satisfactory simulation results. In addition, the thermodynamic properties of the dissolution process such as Gibbs energy, enthalpy, and entropy were calculated using the van’t Hoff equation and the Gibbs equation. The results indicated that the dissolution process was endothermic.

Surface complexation modeling of uranium (Vi) retained onto zirconium diphosphate in presence of organic acids

International Nuclear Information System (INIS)

Almazan T, M. G.; Garcia G, N.; Ordonez R, E.

2010-10-01

In the field of nuclear waste disposal, predictions regarding radionuclide migration through the geosphere, have to take account the effects of natural organic matter. This work presents an investigation of interaction mechanisms between U (Vi) and zirconium diphosphate (ZrP 2 O 7 ) in presence of organic acids (citric acid and oxalic acid). The retention reactions were previously examined using a batch equilibrium method. Previous results showed that U (Vi) retention was more efficient when citric acid or oxalic acid was present in solid surface at lower ph values. In order to determine the retention equilibria for both systems studied, a phosphorescence spectroscopy study was carried out. The experimental data were then fitted using the Constant Capacitance Model included in the FITEQL4.0 code. Previous results concerning surface characterization of ZrP 2 O 7 (surface sites density and surface acidity constants) were used to constraint the modeling. The best fit for U (Vi)/citric acid/ZrP 2 O 7 and U (Vi)/oxalic acid/ZrP 2 O 7 systems considered the formation of a ternary surface complex. (Author)

Characterisation of a thiamine diphosphate-dependent alpha-keto acid decarboxylase from Proteus mirabilis JN458.

Science.gov (United States)

Wang, Biying; Bai, Yajun; Fan, Taiping; Zheng, Xiaohui; Cai, Yujie

2017-10-01

Alpha-keto acid decarboxylases can convert keto acids to their corresponding aldehydes, which are often volatile aroma compounds. The gene encoding α-keto acid decarboxylase in Proteus mirabilis JN458 was cloned, and the enzyme overexpressed in Escherichia coli BL21 (DE3), purified in high yield, and characterised. The molecular weight is 62.291kDa by MALDI-TOF MS, and optimum activity at pH 6.0 and 40-50°C. The enzyme is a typical decarboxylase, dependent on thiamine diphosphate and Mg 2+ as cofactors. For the decarboxylation reaction, the enzyme displayed a broad substrate range. Kinetic parameters were determined using 4-methyl-2-oxopentanoic acid, phenyl pyruvate and 3-methyl-2-oxopentanoic acid as substrates. K m and k cat values for phenyl pyruvate were 0.62mM and 77.38s -1 , respectively, and the k cat /K m value was 124.81mM -1 s -1 . The enzyme properties suggest it may act effectively under cheese ripening conditions. Copyright © 2017. Published by Elsevier Ltd.

Direct incorporation of guanosine 5'-diphosphate into microtubules without guanosine 5'-triphosphate hydrolysis

International Nuclear Information System (INIS)

Hamel, E.; Batra, J.K.; Lin, C.M.

1986-01-01

Using highly purified calf brain tubulin bearing [8- 14 C]guanosine 5'-diphosphate (GDP) in the exchangeable nucleotide site and heat-treated microtubule-associated proteins, the authors have found that a significant proportion of exchangeable-site GDP in microtubules can be incorporated directly during guanosine 5'-triphosphate (GTP) dependent polymerization of tubulin, without an initial exchange of GDP for GTP and subsequent GTP hydrolysis during assembly. The precise amount of GDP incorporated directly into microtubules is highly dependent on specific reaction conditions, being favored by high tubulin concentrations, low GTP and Mg 2+ concentrations, and exogenous GDP in the reaction mixture. Minimum effects were observed with changes in reaction pH or temperature, changes in concentration of microtubule-associated proteins, alteration of the sulfonate buffer, or the presence of a calcium chelator in the reaction mixture. Under conditions most favorable for direct GDP incorporation, about one-third of the GDP in microtubules is incorporated directly (without GTP hydrolysis) and two-thirds is incorporated hydrolytically (as a consequence of GTP hydrolysis). Direct incorporation of GDP occurs in a constant proportion throughout elongation, and the amount of direct incorporation probably reflects the rapid equilibration of GDP and GTP at the exchangeable site that occurs before the onset of assembly

Identification and Functional Characterization of Monofunctional ent-Copalyl Diphosphate and ent-Kaurene Synthases in White Spruce Reveal Different Patterns for Diterpene Synthase Evolution for Primary and Secondary Metabolism in Gymnosperms1[W][OA

Science.gov (United States)

Keeling, Christopher I.; Dullat, Harpreet K.; Yuen, Mack; Ralph, Steven G.; Jancsik, Sharon; Bohlmann, Jörg

2010-01-01

The biosynthesis of the tetracyclic diterpene ent-kaurene is a critical step in the general (primary) metabolism of gibberellin hormones. ent-Kaurene is formed by a two-step cyclization of geranylgeranyl diphosphate via the intermediate ent-copalyl diphosphate. In a lower land plant, the moss Physcomitrella patens, a single bifunctional diterpene synthase (diTPS) catalyzes both steps. In contrast, in angiosperms, the two consecutive cyclizations are catalyzed by two distinct monofunctional enzymes, ent-copalyl diphosphate synthase (CPS) and ent-kaurene synthase (KS). The enzyme, or enzymes, responsible for ent-kaurene biosynthesis in gymnosperms has been elusive. However, several bifunctional diTPS of specialized (secondary) metabolism have previously been characterized in gymnosperms, and all known diTPSs for resin acid biosynthesis in conifers are bifunctional. To further understand the evolution of ent-kaurene biosynthesis as well as the evolution of general and specialized diterpenoid metabolisms in gymnosperms, we set out to determine whether conifers use a single bifunctional diTPS or two monofunctional diTPSs in the ent-kaurene pathway. Using a combination of expressed sequence tag, full-length cDNA, genomic DNA, and targeted bacterial artificial chromosome sequencing, we identified two candidate CPS and KS genes from white spruce (Picea glauca) and their orthologs in Sitka spruce (Picea sitchensis). Functional characterization of the recombinant enzymes established that ent-kaurene biosynthesis in white spruce is catalyzed by two monofunctional diTPSs, PgCPS and PgKS. Comparative analysis of gene structures and enzyme functions highlights the molecular evolution of these diTPSs as conserved between gymnosperms and angiosperms. In contrast, diTPSs for specialized metabolism have evolved differently in angiosperms and gymnosperms. PMID:20044448

Crystallization and preliminary X ray analysis of nucleoside diphosphate kinase 1 from T. cruzi

International Nuclear Information System (INIS)

Gomez Barroso, J.A.; Aguilar, C.F.; Miranda, M.R.; Pereira, C.A.

2009-01-01

Introduction: Trypanosoma cruzi is the etiologic agent of Chagas disease. The Nucleoside diphosphate kinases (NDPKs) are enzymes involved in energy management and nucleoside balance in the cell. T. cruzi TcNDPK1, a canonical isoform. The objective of this work is obtaining protein's crystals, diffract and process the data for tridimensional structure resolution. Materials and Methods: TcNDPK1 was expressed in E. coli as a fusion protein with Nterminal His-tag. TcNDPK1 was overexpressed and purified by FPLC. Crystallization was assayed by sitting drop and hanging drop vapor diffusion method. Crystals was frozen and diffracted on synchrotron x-ray radiation in Campinas (Brasil). The data set collected was reduced and merged using MOSFLM and SCALA programs. Results and Discussion: His-TcNDPK was overexpressed, purified and crystallized. The crystals are diffracted and collected the data to 3.5A. The crystals belong to the trigonal space group P3, with unit cell parameters a=127.94, b=127.84, c=275.49. Structure determination is under way. These results will provide relevant information that could be the first step in rational drug design for treating Chagas disease.(authors)

The correlation between (1)H MRS choline concentrations and MR diffusion trace values in human brain tumors

Czech Academy of Sciences Publication Activity Database

Wagnerová, Dita; Jirů, F.; Dezortová, M.; Vargová, Lýdia; Syková, Eva; Hájek, M.

2009-01-01

Roč. 22, č. 1 (2009), s. 19-31 ISSN 0968-5243 R&D Projects: GA MŠk(CZ) LC554 Grant - others:MZd(CZ) MZ0IKEM2005; EC FP6 project Angiotargeting(XE) 504743 Institutional research plan: CEZ:AV0Z50390512 Keywords : spectroscopic imaging * cholines * diffusion trace Subject RIV: FH - Neurology Impact factor: 1.859, year: 2009

Choline kinase-alpha by regulating cell aggressiveness and drug sensitivity is a potential druggable target for ovarian cancer.

Science.gov (United States)

Granata, A; Nicoletti, R; Tinaglia, V; De Cecco, L; Pisanu, M E; Ricci, A; Podo, F; Canevari, S; Iorio, E; Bagnoli, M; Mezzanzanica, D

2014-01-21

Aberrant choline metabolism has been proposed as a novel cancer hallmark. We recently showed that epithelial ovarian cancer (EOC) possesses an altered MRS-choline profile, characterised by increased phosphocholine (PCho) content to which mainly contribute over-expression and activation of choline kinase-alpha (ChoK-alpha). To assess its biological relevance, ChoK-alpha expression was downmodulated by transient RNA interference in EOC in vitro models. Gene expression profiling by microarray analysis and functional analysis was performed to identify the pathway/functions perturbed in ChoK-alpha-silenced cells, then validated by in vitro experiments. In silenced cells, compared with control, we observed: (I) a significant reduction of both CHKA transcript and ChoK-alpha protein expression; (II) a dramatic, proportional drop in PCho content ranging from 60 to 71%, as revealed by (1)H-magnetic spectroscopy analysis; (III) a 35-36% of cell growth inhibition, with no evidences of apoptosis or modification of the main cellular survival signalling pathways; (IV) 476 differentially expressed genes, including genes related to lipid metabolism. Ingenuity pathway analysis identified cellular functions related to cell death and cellular proliferation and movement as the most perturbed. Accordingly, CHKA-silenced cells displayed a significant delay in wound repair, a reduced migration and invasion capability were also observed. Furthermore, although CHKA silencing did not directly induce cell death, a significant increase of sensitivity to platinum, paclitaxel and doxorubicin was observed even in a drug-resistant context. We showed for the first time in EOC that CHKA downregulation significantly decreased the aggressive EOC cell behaviour also affecting cells' sensitivity to drug treatment. These observations open the way to further analysis for ChoK-alpha validation as a new EOC therapeutic target to be used alone or in combination with conventional drugs.

ORF Alignment: NC_004431 [GENIUS II[Archive

Lifescience Database Archive (English)

Full Text Available EDL933] pdb|1KDT|B Chain B, ... Cytidine Monophosphate Kinase From E.Coli In Complex ... With... 2',3'-Dideoxy-Cytidine Monophosphate pdb|1KDT|A ... Chain A, Cytidine Monophosphate Kinase From E.Coli...|1KDR|B Chain B, Cytidine Monophosphate Kinase From ... E.Coli In Complex With Ara-Cytidine Monophosp...hate ... pdb|1KDR|A Chain A, Cytidine Monophosphate Kinase From ... E.Coli In Complex With Ara

ORF Alignment: NC_002655 [GENIUS II[Archive

Lifescience Database Archive (English)

Full Text Available EDL933] pdb|1KDT|B Chain B, ... Cytidine Monophosphate Kinase From E.Coli In Complex ... With... 2',3'-Dideoxy-Cytidine Monophosphate pdb|1KDT|A ... Chain A, Cytidine Monophosphate Kinase From E.Coli...|1KDR|B Chain B, Cytidine Monophosphate Kinase From ... E.Coli In Complex With Ara-Cytidine Monophosp...hate ... pdb|1KDR|A Chain A, Cytidine Monophosphate Kinase From ... E.Coli In Complex With Ara

ORF Alignment: NC_002695 [GENIUS II[Archive

Lifescience Database Archive (English)

Full Text Available EDL933] pdb|1KDT|B Chain B, ... Cytidine Monophosphate Kinase From E.Coli In Complex ... With... 2',3'-Dideoxy-Cytidine Monophosphate pdb|1KDT|A ... Chain A, Cytidine Monophosphate Kinase From E.Coli...|1KDR|B Chain B, Cytidine Monophosphate Kinase From ... E.Coli In Complex With Ara-Cytidine Monophosp...hate ... pdb|1KDR|A Chain A, Cytidine Monophosphate Kinase From ... E.Coli In Complex With Ara

ORF Alignment: NC_000913 [GENIUS II[Archive

Lifescience Database Archive (English)

Full Text Available EDL933] pdb|1KDT|B Chain B, ... Cytidine Monophosphate Kinase From E.Coli In Complex ... With... 2',3'-Dideoxy-Cytidine Monophosphate pdb|1KDT|A ... Chain A, Cytidine Monophosphate Kinase From E.Coli...|1KDR|B Chain B, Cytidine Monophosphate Kinase From ... E.Coli In Complex With Ara-Cytidine Monophosp...hate ... pdb|1KDR|A Chain A, Cytidine Monophosphate Kinase From ... E.Coli In Complex With Ara

Influence of the temperature in the uranium (Vi) sorption in zirconium diphosphate; Influencia de la temperatura en la sorcion de uranio (VI) en difosfato de circonio

Energy Technology Data Exchange (ETDEWEB)

Garcia G, N.; Solis, D. [Universidad Autonoma del Estado de Mexico, Facultad de Quimica, Paseo Colon y Paseo Tollocan, 50120 Toluca, Estado de Mexico (Mexico); Ordonez R, E., E-mail: nidgg@yahoo.com.mx [ININ, Departamento de Quimica, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

2012-10-15

In the present work was evaluated the uranium (Vi) sorption at 10, 20, 30, 40 and 60 C on the zirconium diphosphate (ZrP{sub 2}O{sub 7}). They were carried out kinetic and isotherms using the method by lots, these will allow to fix the sorption time (kinetic) and to explain the behavior of this sorption in different ph conditions and temperature (isotherm). The quantity of retained uranium in the surface was quantified by means of the fluorescence technique. (Author)

Comparison of C-11-choline and F-18-FDG PET in primary diagnosis and staging of patients with thoracic cancer

NARCIS (Netherlands)

Pieterman, RM; Que, TH; Elsinga, PH; Pruim, J; van Putten, JWG; Willemsen, ATM; Vaalburg, W; Groen, HJM

PET with F-18-FDG is used for detection and staging of thoracic cancer; however, more specific PET radiopharmaceuticals would be welcome. C-11-labeled choline (CHOL) is a new radiopharmaceutical potentially useful for tumor imaging, since it is incorporated into cell membranes as

Revisiting the Latency of Uridine Diphosphate-Glucuronosyltransferases (UGTs—How Does the Endoplasmic Reticulum Membrane Influence Their Function?

Directory of Open Access Journals (Sweden)

Yuejian Liu

2017-08-01

Full Text Available Uridine diphosphate-glucuronosyltransferases (UGTs are phase 2 conjugation enzymes mainly located in the endoplasmic reticulum (ER of the liver and many other tissues, and can be recovered in artificial ER membrane preparations (microsomes. They catalyze glucuronidation reactions in various aglycone substrates, contributing significantly to the body’s chemical defense mechanism. There has been controversy over the last 50 years in the UGT field with respect to the explanation for the phenomenon of latency: full UGT activity revealed by chemical or physical disruption of the microsomal membrane. Because latency can lead to inaccurate measurements of UGT activity in vitro, and subsequent underprediction of drug clearance in vivo, it is important to understand the mechanisms behind this phenomenon. Three major hypotheses have been advanced to explain UGT latency: compartmentation, conformation, and adenine nucleotide inhibition. In this review, we discuss the evidence behind each hypothesis in depth, and suggest some additional studies that may reveal more information on this intriguing phenomenon.

Choline acetyltransferase-containing neurons in the human parietal neocortex

Directory of Open Access Journals (Sweden)

V Benagiano

2009-06-01

Full Text Available A number of immunocytochemical studies have indicated the presence of cholinergic neurons in the cerebral cortex of various species of mammals. Whether such cholinergic neurons in the human cerebral cortex are exclusively of subcortical origin is still debated. In this immunocytochemical study, the existence of cortical cholinergic neurons was investigated on surgical samples of human parietal association neocortex using a highly specific monoclonal antibody against choline acetyltransferase (ChAT, the acetylcholine biosynthesising enzyme. ChAT immunoreactivity was detected in a subpopulation of neurons located in layers II and III. These were small or medium-sized pyramidal neurons which showed cytoplasmic immunoreactivity in the perikarya and processes, often in close association to blood microvessels. This study, providing demonstration of ChAT neurons in the human parietal neocortex, strongly supports the existence of intrinsic cholinergic innervation of the human neocortex. It is likely that these neurons contribute to the cholinergic innervation of the intracortical microvessels.

The concentration of N-acetyl aspartate, creatine + phosphocreatine, and choline in different parts of the brain in adulthood and senium

DEFF Research Database (Denmark)

Christiansen, P; Toft, P; Larsson, H B

1993-01-01

The fully relaxed water signal was used as an internal standard in a STEAM experiment to calculate the concentrations of the metabolites: N-acetyl aspartate (NAA), creatine + phosphocreatine (Cr + PCr), and choline (Cho) containing compounds in four different parts of the brain in two age groups...

New Acquisition Protocol of 18F-Choline PET/CT in Prostate Cancer Patients: Review of the Literature about Methodology and Proposal of Standardization

Directory of Open Access Journals (Sweden)

Sotirios Chondrogiannis

2014-01-01

Full Text Available Purpose. (1 To evaluate a new acquisition protocol of 18F-choline (FCH PET/CT for prostate cancer patients (PC, (2 to review acquisition 18F-choline PET/CT methodology, and (3 to propose a standardized acquisition protocol on FCH PET/CT in PC patients. Materials. 100 consecutive PC patients (mean age 70.5 years, mean PSA 21.35 ng/mL were prospectively evaluated. New protocol consisted of an early scan of the pelvis immediately after the injection of the tracer (1 bed position of 4 min followed by a whole body scan at one 1 hour. Early and 1 hour images were compared for interfering activity and pathologic findings. Results. The overall detection rate of FCH PET/CT was 64%. The early static images of the pelvis showed absence of radioactive urine in ureters, bladder, or urethra which allowed a clean evaluation of the prostatic fossae. Uptake in the prostatic region was better visualized in the early phase in 26% (7/30 of cases. Other pelvic pathologic findings (bone and lymph nodes were visualized in both early and late images. Conclusion. Early 18F-choline images improve visualization of abnormal uptake in prostate fossae. All pathologic pelvic deposits (prostate, lymph nodes, and bone were visualized in both early and late images.

Steady state kinetic model for the binding of substrates and allosteric effectors to Escherichia coli phosphoribosyl-diphosphate synthase

DEFF Research Database (Denmark)

Willemoës, Martin; Hove-Jensen, Bjarne; Larsen, Sine

2000-01-01

A steady state kinetic investigation of the Pi activation of 5-phospho-D-ribosyl α-1-diphosphate synthase from Escherichia coli suggests that Pi can bind randomly to the enzyme either before or after an ordered addition of free Mg2+ and substrates. Unsaturation with ribose 5-phosphate increased...... the apparent cooperativity of Pi activation. At unsaturating Pi concentrations partial substrate inhibition by ribose 5-phosphate was observed. Together these results suggest that saturation of the enzyme with Pi directs the subsequent ordered binding of Mg2+ and substrates via a fast pathway, whereas...... saturation with ribose 5-phosphate leads to the binding of Mg2+ and substrates via a slow pathway where Pi binds to the enzyme last. The random mechanism for Pi binding was further supported by studies with competitive inhibitors of Mg2+, MgATP, and ribose 5-phosphate that all appeared noncompetitive when...

The uridine diphosphate glucuronosyltransferases: quantitative structure-activity relationships for hydroxyl polychlorinated biphenyl substrates

Energy Technology Data Exchange (ETDEWEB)

Wang, Degao [Dalian University of Technology, Department of Environmental Science and Technology, Dalian (China)

2005-10-01

Quantitative structure-activity relationships (QSARs), which relate the glucuronidation of hydroxyl polychlorinated biphenyls (OH-PCBs) - catalyzed by the uridine diphosphate glucuronosyltransferases (UGTs) - to their physicochemical properties and molecular structural parameters, can be used to predict the rate constants and interpret the mechanism of glucuronidation. In this study, QSARs have been developed that use 23 semi-empirical calculated quantum chemical descriptors to predict the logarithms of the constants 1/K{sub m} and V{sub max}, related to enzyme kinetics. A partial least squares regression method was used to select the optimal set of descriptors to minimize the multicollinearity between the descriptors, as well as to maximize the cross-validated coefficient (Q{sup 2} {sub cum}) values. The key descriptors affecting log(1/K{sub m}) were E{sub lumo}- E{sub homo} (the energy gap between the lowest unoccupied molecular orbital and the highest occupied molecular orbital) and q{sub C}{sup -} (the largest negative net atomic charge on a carbon atom), while the key descriptors affecting log V{sub max} were the polarizability {alpha}, the Connolly solvent-excluded volume (CSEV), and logP (the logarithm of the partition coefficient for octanol/water). From the results obtained it can be concluded that hydrophobic and electronic aspects of OH-PCBs are important in the glucuronidation of OH-PCBs. (orig.)

Surface and micellar properties of Chloroquine Diphosphate and its interactions with surfactants and Human Serum Albumin

International Nuclear Information System (INIS)

Usman, Muhammad; Siddiq, Mohammad

2013-01-01

Highlights: ► Free energy of adsorption is more negative than free energy of micellization. ► Shifts in UV/Visible spectra in presence of SDS indicated interaction of CLQ with SDS. ► The decrease in fluorescence intensity of HSA by CLQ shows its binding with HSA. -- Abstract: This manuscript addresses the physicochemical behavior of an antimalarial drug Chloroquine Diphosphate (CLQ) as well as its interaction with anionic surfactants and Human Serum Albumin (HSA). Surface tension and specific conductivity were employed to detect the critical micelle concentration (CMC) and thus its surface and thermodynamic parameters were calculated. Solubilization of this drug within micelles of anionic surfactant sodium dodecyl sulfate (SDS) has also been studied. UV/Visible spectroscopy was used to calculate partition coefficient (K x ), free energy of partition and number of drug molecules per micelle. The complexation of drug with HSA at physiological conditions (pH 7.4) has also been analyzed by using UV/Visible and fluorescence spectroscopy. The values of drug-protein binding constant, number of binding sites and free energy of binding were calculated

18F-FDG versus 11C-choline PET/CT for the imaging of advanced head and neck cancer after combined intra-arterial chemotherapy and radiotherapy: the time period during which PET/CT can reliably detect non-recurrence

International Nuclear Information System (INIS)

Ito, Kimiteru; Matsuda, Hiroshi; Yokoyama, Jyunkichi; Kubota, Kazuo; Morooka, Miyako; Shiibashi, Michio

2010-01-01

The purpose of this prospective study was to evaluate the usefulness of 18 F-fluorodeoxyglucose (FDG) and 11 C-choline positron emission tomography (PET)/computed tomography (CT) for detecting recurrences of advanced head and neck cancer after combined intra-arterial chemotherapy and radiotherapy. Additionally, we surveyed the time period during which an effective negative predictive value could be maintained after the first follow-up PET/CT examination and estimated the optimal timing of a second PET/CT examination for detecting late recurrences. Fifty-three subjects (36 men and 17 women; mean age: 59.4±11.5 years) with advanced head and neck squamous cell carcinoma were recruited. Post-treatment 18 F-FDG PET/CT and 11 C-choline examinations were performed in all patients between 8 and 12 weeks after combined intra-arterial chemotherapy and radiotherapy. The PET/CT images were evaluated using a patient-based analysis and a lesion-based analysis. All of the patients were prospectively followed for at least 9 months after the post-treatment PET/CT examination, with surveillance using conventional images (including CT and/or MRI) and a physical examination performed every 3 months. Recurrences, as determined using the patient-based analysis, were eventually confirmed in 18, 6 and 5 patients at 3, 4-6 and 7-9 months after the post-treatment PET/CT examination, respectively. The sensitivity and specificity of the 18F-FDG PET/CT and the 11C-choline PET/CT examinations to predict recurrence within 3 months were higher (FDG: 89 and 91%; choline: 83 and 80%, respectively) than for recurrence detection 6 months (FDG: 67 and 90%; choline: 62 and 76%, respectively) and 9 months later (FDG: 59 and 92%; choline: 55 and 75%, respectively). The lesion-based analysis showed that the maximum standardized uptake value of 18 F-FDG and 11 C-choline in the recurrent lesions were correlated with each other, compared with their relation in scar tissues (R 2 = 0.492 and 0

Specificity of choline metabolites for in vivo diagnosis of breast cancer using 1H MRS at 1.5 T

International Nuclear Information System (INIS)

Stanwell, Peter; Gluch, Laurence; Lean, Cynthia; Malycha, Peter; Mountford, Carolyn; Clark, David; Tomanek, Boguslaw; Baker, Luke; Giuffre, Bruno

2005-01-01

The purpose was to determine if in vivo proton magnetic resonance spectroscopy ( 1 H MRS) at 1.5 T can accurately provide the correct pathology of breast disease. Forty-three asymptomatic volunteers including three lactating mothers were examined and compared with 21 breast cancer patients. Examinations were undertaken at 1.5 T using a purpose-built transmit-receive single breast coil. Single voxel spectroscopy was undertaken using echo times of 135 and 350 ms. The broad composite resonance at 3.2 ppm, which includes contributions from choline, phosphocholine (PC), glycerophosphocholine (GPC), myo-inositol and taurine, was found not to be a unique marker for malignancy providing a diagnostic sensitivity and specificity of 80.0 and 86.0%, respectively. This was due to three of the asymptomatic volunteers and all of the lactating mothers also generating the broad composite resonance at 3.2 ppm. Optimised post-acquisitional processing of the spectra resolved a resonance at 3.22 ppm, consistent with PC, in patients with cancer. In contrast the spectra recorded for three false-positive volunteers, and the three lactating mothers had a resonance centred at 3.28 ppm (possibly taurine, myo-inositol or GPC). This improved the specificity of the test to 100%. Careful referencing of the spectra and post-acquisitional processing intended to optimise spectral resolution of in vivo MR proton spectra from human breast tissue resolves the composite choline resonance. This allows the distinction of patients with malignant disease from volunteers with a sensitivity of 80% and specificity of 100%. Therefore, resolution of the composite choline resonance into its constituent components improves the specificity of the in vivo 1 H MRS method, but does not overcome the problem of 20% false-negatives. (orig.)

Effects of dietary amino acids, carbohydrates, and choline on neurotransmitter synthesis

Science.gov (United States)

Wurtman, Richard J.

1988-01-01

The ability of a meal to increase or decrease brain neurotransmitter synthesis has been studied. It is concluded that brain serotonin synthesis is directly controlled by the proportions of carbohydrate to protein in meals and snacks that increase or decrease brain tryptophan levels, thereby changing the substrate saturation of tryptophan hydroxylase and the rate of serotonin synthesis. The ability of serotoninergic neurons to have their output coupled to dietary macronutrients enables them to function as sensors of peripheral metabolism, and to subserve an important role in the control of appetite. The robust and selective responses of catecholaminergic and cholinergic neurons to supplemental tyrosine and choline suggest that these compounds may become useful as a new type of drug for treating deseases or conditions in which adequate quantities of the transmitter would otherwise be unavailable.

Blockage of High-Affinity Choline Transporter Increases Visceral Hypersensitivity in Rats with Chronic Stress

Science.gov (United States)

2018-01-01

Background Visceral hypersensitivity is a common feature of irritable bowel syndrome. Cholinergic system involves in the development of visceral hypersensitivity, and high-affinity choline transporter (CHT1) is of crucial importance in choline uptake system. However, involvement of CHT1 in visceral hypersensitivity remains unknown. The research aimed to study the CHT1 expression in dorsal root ganglions (DRGs) and the role of CHT1 in visceral hypersensitivity. Methods Repetitive water avoidance stress (WAS) was used to induce visceral hypersensitivity in rats. Colorectal distension (CRD) was determined, and the abdominal withdrawal reflex (AWR) and threshold intensity data were recorded to measure the visceral sensitivity. After intraperitoneal injection of hemicholinium-3 (HC-3), the specific inhibitor of CHT1, CRD data were also recorded. The CHT1 expression of DRGs was investigated by Western blotting, immunohistochemistry, and quantitative RT-PCR. Acetylcholine levels in the DRGs were detected by the assay kit. Results Repetitive WAS increased the AWR score of CRD at high distension pressure and decreased the mean threshold of rats. The CHT1 expression and acetylcholine concentration of DRG were significantly increased in WAS rats. After the administration of HC-3, the AWR score in WAS group was significantly increased at higher distension pressure while the threshold intensity was significantly reduced compared to the normal saline group. Acetylcholine concentration was significantly lower than the normal saline rats. Conclusion Our research firstly reports that CHT1 is overexpressed in noninflammatory visceral hypersensitivity, and blockage of CHT1 can enhance the visceral hypersensitivity. CHT1 may play an inhibitory role in visceral hypersensitivity. PMID:29849603

Structural determinants of enzyme binding affinity: the E1 component of pyruvate dehydrogenase from Escherichia coli in complex with the inhibitor thiamin thiazolone diphosphate.

Science.gov (United States)

Arjunan, Palaniappa; Chandrasekhar, Krishnamoorthy; Sax, Martin; Brunskill, Andrew; Nemeria, Natalia; Jordan, Frank; Furey, William

2004-03-09

Thiamin thiazolone diphosphate (ThTDP), a potent inhibitor of the E1 component from the Escherichia coli pyruvate dehydrogenase multienzyme complex (PDHc), binds to the enzyme with greater affinity than does the cofactor thiamin diphosphate (ThDP). To identify what determines this difference, the crystal structure of the apo PDHc E1 component complex with ThTDP and Mg(2+) has been determined at 2.1 A and compared to the known structure of the native holoenzyme, PDHc E1-ThDP-Mg(2+) complex. When ThTDP replaces ThDP, reorganization occurs in the protein structure in the vicinity of the active site involving positional and conformational changes in some amino acid residues, a change in the V coenzyme conformation, addition of new hydration sites, and elimination of others. These changes culminate in an increase in the number of hydrogen bonds to the protein, explaining the greater affinity of the apoenzyme for ThTDP. The observed hydrogen bonding pattern is not an invariant feature of ThDP-dependent enzymes but rather specific to this enzyme since the extra hydrogen bonds are made with nonconserved residues. Accordingly, these sequence-related hydrogen bonding differences likewise explain the wide variation in the affinities of different thiamin-dependent enzymes for ThTDP and ThDP. The sequence of each enzyme determines its ability to form hydrogen bonds to the inhibitor or cofactor. Mechanistic roles are suggested for the aforementioned reorganization and its reversal in PDHc E1 catalysis: to promote substrate binding and product release. This study also provides additional insight into the role of water in enzyme inhibition and catalysis.

Intensity Modulated Radiation Therapy Dose Painting for Localized Prostate Cancer Using 11C-choline Positron Emission Tomography Scans

International Nuclear Information System (INIS)

Chang, Joe H.; Lim Joon, Daryl; Lee, Sze Ting; Gong, Sylvia J.; Anderson, Nigel J.; Scott, Andrew M.; Davis, Ian D.; Clouston, David; Bolton, Damien; Hamilton, Christopher S.; Khoo, Vincent

2012-01-01

Purpose: To demonstrate the technical feasibility of intensity modulated radiation therapy (IMRT) dose painting using 11 C-choline positron emission tomography PET scans in patients with localized prostate cancer. Methods and Materials: This was an RT planning study of 8 patients with prostate cancer who had 11 C-choline PET scans prior to radical prostatectomy. Two contours were semiautomatically generated on the basis of the PET scans for each patient: 60% and 70% of the maximum standardized uptake values (SUV 60% and SUV 70% ). Three IMRT plans were generated for each patient: PLAN 78 , which consisted of whole-prostate radiation therapy to 78 Gy; PLAN 78-90 , which consisted of whole-prostate RT to 78 Gy, a boost to the SUV 60% to 84 Gy, and a further boost to the SUV 70% to 90 Gy; and PLAN 72-90 , which consisted of whole-prostate RT to 72 Gy, a boost to the SUV 60% to 84 Gy, and a further boost to the SUV 70% to 90 Gy. The feasibility of these plans was judged by their ability to reach prescription doses while adhering to published dose constraints. Tumor control probabilities based on PET scan-defined volumes (TCP PET ) and on prostatectomy-defined volumes (TCP path ), and rectal normal tissue complication probabilities (NTCP) were compared between the plans. Results: All plans for all patients reached prescription doses while adhering to dose constraints. TCP PET values for PLAN 78 , PLAN 78-90 , and PLAN 72-90 were 65%, 97%, and 96%, respectively. TCP path values were 71%, 97%, and 89%, respectively. Both PLAN 78-90 and PLAN 72-90 had significantly higher TCP PET (P=.002 and .001) and TCP path (P 78 . PLAN 78-90 and PLAN 72-90 were not significantly different in terms of TCP PET or TCP path . There were no significant differences in rectal NTCPs between the 3 plans. Conclusions: IMRT dose painting for localized prostate cancer using 11 C-choline PET scans is technically feasible. Dose painting results in higher TCPs without higher NTCPs.

SU-F-J-101: Stereotactic Body Radiation Therapy Planning for Primary Prostate Cancer with Selective Intraprostatic Boost Determined by 18F-Choline PET/CT

Energy Technology Data Exchange (ETDEWEB)

Wu, L [Cancer Hospital of Shantou University Medical College, Shantou, Guangdong (China); Wang, H; Kuang, Y [University of Nevada Las Vegas, Las Vegas, NV (United States); Hirata, E; Kwee, S [Queen’s Medical Center, Honolulu, HI (United States)

2016-06-15

Purpose: To investigate the utility of {sup 18}F-choline positron emission tomography (PET) scans guidance for SBRT dose painting in patients with prostate cancer and its impact on tumor control probability (TCP) and normal tissue complication probability (NTCP). Methods: Twenty seven patients with localized prostate cancer who had {sup 18}F-choline PET/CT scan prior to treatment were included. A pair of nested intraprostatic dominant lesion (IDL) contours (IDL{sub suv60%} and IDL{sub suv70%}) were generated for each patient based on 60% and 70% of maximum prostate uptake on the {sup 18}F-choline PET images. GTV{sub reg} was delineated on prostate according to the gland boundary seen on CT images. The PTVs (PTV{sub suv60%} and PTV{sub suv70%}) were defined as respective IDLs with a 3-mm margin posteriorly and 5 mm in all other dimensions. Two 5-fraction SBRT plans using VMAT technique along with 10 MV FFF beams, plan{sub 36Gy} and plan{sub 50–55Gy}, were generated for each patient. All plans included a dose of 36.25 Gy prescribed to PTV{sub reg}. The Plan{sub 50–55Gy} also included a simultaneous boost dose of 50 Gy and 55 Gy prescribed to the PTV{sub suv60%} and PTV{sub suv70%}, respectively. The utility of {sup 18}F-Choline PET-guided SBRT dose escalation was evaluated by its ability to achieve the prescription dose objectives while adhering to organ-at-risk (OAR) dose constraints. The TCP and NTCP calculated by radiological models were also compared between two plans for each patient. Results: In all 54 SBRT plans generated, the planning objectives and dose constraints were met without exception. Plan{sub 50–55Gy} had a significantly higher dose in PTV{sub suv60%} and PTV{sub suv70%} than those in Plan{sub 36Gy} (p < 0.05), respectively, while still maintaining a safe OAR sparing profile. In addition, plan{sub 50–55Gy} had significantly higher TCP than plan{sub 36Gy}. Conclusion: Using VMAT with FFF beams to incorporate a simultaneous {sup 18}F-choline

Specificity of choline metabolites for in vivo diagnosis of breast cancer using {sup 1}H MRS at 1.5 T

Energy Technology Data Exchange (ETDEWEB)

Stanwell, Peter; Gluch, Laurence; Lean, Cynthia; Malycha, Peter; Mountford, Carolyn [Royal North Shore Hospital, Institute for Magnetic Resonance Research and Department of Magnetic Resonance in Medicine, University of Sydney, St Leonards, NSW (Australia); Clark, David [Breast Centre, Waratah, NSW (Australia); Tomanek, Boguslaw [National Research Council Canada, Institute for Biodiagnostics, Winnipeg, MB (Canada); Baker, Luke [Sydney Adventist Hospital, Department of Radiology, Wahroonga, NSW (Australia); Giuffre, Bruno [Royal North Shore Hospital, Department of Radiology, St Leonards, NSW (Australia)

2005-05-01

The purpose was to determine if in vivo proton magnetic resonance spectroscopy ({sup 1}H MRS) at 1.5 T can accurately provide the correct pathology of breast disease. Forty-three asymptomatic volunteers including three lactating mothers were examined and compared with 21 breast cancer patients. Examinations were undertaken at 1.5 T using a purpose-built transmit-receive single breast coil. Single voxel spectroscopy was undertaken using echo times of 135 and 350 ms. The broad composite resonance at 3.2 ppm, which includes contributions from choline, phosphocholine (PC), glycerophosphocholine (GPC), myo-inositol and taurine, was found not to be a unique marker for malignancy providing a diagnostic sensitivity and specificity of 80.0 and 86.0%, respectively. This was due to three of the asymptomatic volunteers and all of the lactating mothers also generating the broad composite resonance at 3.2 ppm. Optimised post-acquisitional processing of the spectra resolved a resonance at 3.22 ppm, consistent with PC, in patients with cancer. In contrast the spectra recorded for three false-positive volunteers, and the three lactating mothers had a resonance centred at 3.28 ppm (possibly taurine, myo-inositol or GPC). This improved the specificity of the test to 100%. Careful referencing of the spectra and post-acquisitional processing intended to optimise spectral resolution of in vivo MR proton spectra from human breast tissue resolves the composite choline resonance. This allows the distinction of patients with malignant disease from volunteers with a sensitivity of 80% and specificity of 100%. Therefore, resolution of the composite choline resonance into its constituent components improves the specificity of the in vivo {sup 1}H MRS method, but does not overcome the problem of 20% false-negatives. (orig.)

Identification of a Post-translational Modification with Ribitol-Phosphate and Its Defect in Muscular Dystrophy

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Motoi Kanagawa

2016-03-01

Full Text Available Glycosylation is an essential post-translational modification that underlies many biological processes and diseases. α-dystroglycan (α-DG is a receptor for matrix and synaptic proteins that causes muscular dystrophy and lissencephaly upon its abnormal glycosylation (α-dystroglycanopathies. Here we identify the glycan unit ribitol 5-phosphate (Rbo5P, a phosphoric ester of pentose alcohol, in α-DG. Rbo5P forms a tandem repeat and functions as a scaffold for the formation of the ligand-binding moiety. We show that enzyme activities of three major α-dystroglycanopathy-causing proteins are involved in the synthesis of tandem Rbo5P. Isoprenoid synthase domain-containing (ISPD is cytidine diphosphate ribitol (CDP-Rbo synthase. Fukutin and fukutin-related protein are sequentially acting Rbo5P transferases that use CDP-Rbo. Consequently, Rbo5P glycosylation is defective in α-dystroglycanopathy models. Supplementation of CDP-Rbo to ISPD-deficient cells restored α-DG glycosylation. These findings establish the molecular basis of mammalian Rbo5P glycosylation and provide insight into pathogenesis and therapeutic strategies in α-DG-associated diseases.

Cloning and expression analysis of two dehydrodolichyl diphosphate synthase genes from Tripterygium wilfordii

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Lin-Hui Gao

2018-01-01

Full Text Available Objective: To clone and investigate two dehydrodolichyl diphosphate synthase genes of Tripterygium wilfordii by bioinformatics and tissue expression analysis. Materials and Methods: According to the T. wifordii transcriptome database, specific primers were designed to clone the TwDHDDS1 and TwDHDDS2 genes via PCR. Based on the cloned sequences, protein structure prediction, multiple sequence alignment and phylogenetic tree construction were performed. The expression levels of the genes in different tissues of T. wilfordii were measured by real-time quantitative PCR. Results: The TwDHDDS1 gene encompassed a 873 bp open reading frame (ORF and encoded a protein of 290 amino acids. The calculated molecular weight of the translated protein was about 33.46 kDa, and the theoretical isoelectric point (pI was 8.67. The TwDHDDS2 encompassed a 768 bp ORF, encoding a protein of 255 amino acids with a calculated molecular weight of about 21.19 kDa, and a theoretical isoelectric point (pI of 7.72. Plant tissue expression analysis indicated that TwDHDDS1 and TwDHDDS2 both have relatively ubiquitous expression in all sampled organ tissues, but showed the highest transcription levels in the stems. Conclusions: The results of this study provide a basis for further functional studies of TwDHDDS1 and TwDHDDS2. Most importantly, these genes are promising genetic targets for the regulation of the biosynthetic pathways of important bioactive terpenoids such as triptolide.

Persistent fibrosis in the liver of choline-deficient and iron-supplemented L-amino acid-defined diet-induced nonalcoholic steatohepatitis rat due to continuing oxidative stress after choline supplementation

International Nuclear Information System (INIS)

Takeuchi-Yorimoto, Ayano; Noto, Takahisa; Yamada, Atsushi; Miyamae, Yoichi; Oishi, Yuji; Matsumoto, Masahiro

2013-01-01

Nonalcoholic steatohepatitis (NASH) is characterized by combined pathology of steatosis, lobular inflammation, fibrosis, and hepatocellular degeneration, with systemic symptoms of diabetes or hyperlipidemia, all in the absence of alcohol abuse. Given the therapeutic importance and conflicting findings regarding the potential for healing the histopathologic features of NASH in humans, particularly fibrosis, we investigated the reversibility of NASH-related findings in Wistar rats fed a choline-deficient and iron-supplemented L-amino acid-defined (CDAA) diet for 12 weeks, with a recovery period of 7 weeks, during which the diets were switched to a choline-sufficient and iron-supplemented L-amino acid-defined (CSAA) one. Analysis showed that steatosis and inflammation were significantly resolved by the end of the recovery period, along with decreases in AST and ALT activities within 4 weeks. In contrast, fibrosis remained even after the recovery period, to an extent similar to that in continuously CDAA-fed animals. Real-time reverse transcriptase-polymerase chain reaction, Western blot, and immunohistochemical investigations revealed that expression of some factors indicating oxidative stress (CYP2E1, 4-HNE, and iNOS) were elevated, whereas catalase and SOD1 were decreased, and a hypoxic state and CD34-positive neovascularization were evident even after the recovery period, although the fibrogenesis pathway by activated α-SMA-positive hepatic stellate cells via TGF-β and TIMPs decreased to the CSAA group level. In conclusion, persistent fibrosis was noted after the recovery period of 7 weeks, possibly due to sustained hypoxia and oxidative stress supposedly caused by capillarization. Otherwise, histopathological features of steatosis and inflammation, as well as serum AST and ALT activities, were recovered. - Highlights: ► NASH-like liver lesions are induced in rats by feeding a CDAA diet. ► Steatosis and lobular inflammation are resolved after switching to a

Persistent fibrosis in the liver of choline-deficient and iron-supplemented L-amino acid-defined diet-induced nonalcoholic steatohepatitis rat due to continuing oxidative stress after choline supplementation

Energy Technology Data Exchange (ETDEWEB)

Takeuchi-Yorimoto, Ayano, E-mail: ayano.takeuchi@astellas.com [Drug Safety Research Labs, Astellas Pharma Inc., Osaka 532-8514 (Japan); Noto, Takahisa [Drug Safety Research Labs, Astellas Pharma Inc., Osaka 532-8514 (Japan); Yamada, Atsushi [Drug Safety Research Division, Astellas Research Technologies Co., Ltd., Osaka 532-8514 (Japan); Miyamae, Yoichi; Oishi, Yuji; Matsumoto, Masahiro [Drug Safety Research Labs, Astellas Pharma Inc., Osaka 532-8514 (Japan)

2013-05-01

Nonalcoholic steatohepatitis (NASH) is characterized by combined pathology of steatosis, lobular inflammation, fibrosis, and hepatocellular degeneration, with systemic symptoms of diabetes or hyperlipidemia, all in the absence of alcohol abuse. Given the therapeutic importance and conflicting findings regarding the potential for healing the histopathologic features of NASH in humans, particularly fibrosis, we investigated the reversibility of NASH-related findings in Wistar rats fed a choline-deficient and iron-supplemented L-amino acid-defined (CDAA) diet for 12 weeks, with a recovery period of 7 weeks, during which the diets were switched to a choline-sufficient and iron-supplemented L-amino acid-defined (CSAA) one. Analysis showed that steatosis and inflammation were significantly resolved by the end of the recovery period, along with decreases in AST and ALT activities within 4 weeks. In contrast, fibrosis remained even after the recovery period, to an extent similar to that in continuously CDAA-fed animals. Real-time reverse transcriptase-polymerase chain reaction, Western blot, and immunohistochemical investigations revealed that expression of some factors indicating oxidative stress (CYP2E1, 4-HNE, and iNOS) were elevated, whereas catalase and SOD1 were decreased, and a hypoxic state and CD34-positive neovascularization were evident even after the recovery period, although the fibrogenesis pathway by activated α-SMA-positive hepatic stellate cells via TGF-β and TIMPs decreased to the CSAA group level. In conclusion, persistent fibrosis was noted after the recovery period of 7 weeks, possibly due to sustained hypoxia and oxidative stress supposedly caused by capillarization. Otherwise, histopathological features of steatosis and inflammation, as well as serum AST and ALT activities, were recovered. - Highlights: ► NASH-like liver lesions are induced in rats by feeding a CDAA diet. ► Steatosis and lobular inflammation are resolved after switching to a

A choline derivate-modified nanoprobe for glioma diagnosis using MRI

Science.gov (United States)

Li, Jianfeng; Huang, Shixian; Shao, Kun; Liu, Yang; An, Sai; Kuang, Yuyang; Guo, Yubo; Ma, Haojun; Wang, Xuxia; Jiang, Chen

2013-04-01

Gadolinium (Gd) chelate contrast-enhanced magnetic resonance imaging (MRI) is a preferred method of glioma detection and preoperative localisation because it offers high spatial resolution and non-invasive deep tissue penetration. Gd-based contrast agents, such as Gd-diethyltriaminepentaacetic acid (DTPA-Gd, Magnevist), are widely used clinically for tumor diagnosis. However, the Gd-based MRI approach is limited for patients with glioma who have an uncompromised blood-brain barrier (BBB). Moreover, the rapid renal clearance and non-specificity of such contrast agents further hinders their prevalence. We present a choline derivate (CD)-modified nanoprobe with BBB permeability, glioma specificity and a long blood half-life. Specific accumulation of the nanoprobe in gliomas and subsequent MRI contrast enhancement are demonstrated in vitro in U87 MG cells and in vivo in a xenograft nude model. BBB and glioma dual targeting by this nanoprobe may facilitate precise detection of gliomas with an uncompromised BBB and may offer better preoperative and intraoperative tumor localization.

Temperature effects on the interaction mechanisms between the europium (III) and uranyl ions and zirconium diphosphate

International Nuclear Information System (INIS)

Finck, N.

2006-10-01

Temperature should remain higher than 25 C in the near field environment of a nuclear waste repository for thousands years. In this context, the aim of this work is to study the temperature influence on the interaction mechanisms between europium (III) and uranyl ions and zirconium diphosphate, as well as the influence of a complexing medium (nitrate) on the sorption of the lanthanide. The experimental definition of the equilibria was achieved by combining a structural investigation with the macroscopic sorption data. Surface complexes were characterized at all temperatures (25 C to 90 C) by TRLFS experiments carried out on dry and in situ samples using an oven. This characterization was completed by XPS experiments carried out at 25 C on samples prepared at 25 C and 90 C. The reaction constants (surface hydration and cations sorption) were obtained by simulating the experimental data with the constant capacitance surface complexation model. The reaction constants temperature dependency allowed one to characterize thermodynamically the different reactions by application of the van't Hoff relation. The validity of this law was tested by performing microcalorimetric measurements of the sorption heat for both cations. (author)

Repeatability of two-dimensional chemical shift imaging multivoxel proton magnetic resonance spectroscopy for measuring human cerebral choline-containing compounds.

Science.gov (United States)

Puri, Basant K; Egan, Mary; Wallis, Fintan; Jakeman, Philip

2018-03-22

To investigate the repeatability of proton magnetic resonance spectroscopy in the in vivo measurement of human cerebral levels of choline-containing compounds (Cho). Two consecutive scans were carried out in six healthy resting subjects at a magnetic field strength of 1.5 T. On each occasion, neurospectroscopy data were collected from 64 voxels using the same 2D chemical shift imaging (CSI) sequence. The data were analyzed in the same way, using the same software, to obtain the values for each voxel of the ratio of Cho to creatine. The Wilcoxon related-samples signed-rank test, coefficient of variation (CV), repeatability coefficient (RC), and intraclass correlation coefficient (ICC) were used to assess the repeatability. The CV ranged from 2.75% to 33.99%, while the minimum RC was 5.68%. There was excellent reproducibility, as judged by significant ICC values, in 26 voxels. Just three voxels showed significant differences according to the Wilcoxon related-samples signed-rank test. It is therefore concluded that when CSI multivoxel proton neurospectroscopy is used to measure cerebral choline-containing compounds at 1.5 T, the reproducibility is highly acceptable.

Effect of Vegan Fecal Microbiota Transplantation on Carnitine- and Choline-Derived Trimethylamine-N-Oxide Production and Vascular Inflammation in Patients With Metabolic Syndrome

NARCIS (Netherlands)

Smits, L.P.; Kootte, R.S.; Levin, E.; Prodan, A.; Fuentes, S.; Zoetendal, E.G.; Wang, Z; Levison, B.S.; Cleophas, M.C.P.; Kemper, E.M.; Dallinga-Thie, G.M.; Groen, A.K.; Joosten, L.A.B.; Netea, M.G.; Stroes, E.S.; Vos, W.M. de; Hazen, S.L.; Nieuwdorp, M.

2018-01-01

BACKGROUND: Intestinal microbiota have been found to be linked to cardiovascular disease via conversion of the dietary compounds choline and carnitine to the atherogenic metabolite TMAO (trimethylamine-N-oxide). Specifically, a vegan diet was associated with decreased plasma TMAO levels and nearly

Effect of vegan fecal microbiota transplantation on carnitine- and choline-derived trimethylamine-N-oxide production and vascular inflammation in patients with metabolic syndrome

NARCIS (Netherlands)

Smits, Loek P.; Kootte, Ruud S.; Levin, Evgeni; Prodan, Andrei; Fuentes, Susana; Zoetendal, Erwin G.; Wang, Zeneng; Levison, Bruce S.; Cleophas, Maartje C.P.; Kemper, E.M.; Dallinga-Thie, Geesje M.; Groen, Albert K.; Joosten, Leo A.B.; Netea, Mihai G.; Stroes, Erik S.G.; Vos, de Willem M.; Hazen, Stanley L.; Nieuwdorp, Max

2018-01-01

Background--Intestinal microbiota have been found to be linked to cardiovascular disease via conversion of the dietary compounds choline and carnitine to the atherogenic metabolite TMAO (trimethylamine-N-oxide). Specifically, a vegan diet was associated with decreased plasma TMAO levels and nearly

Blockage of High-Affinity Choline Transporter Increases Visceral Hypersensitivity in Rats with Chronic Stress

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Chen Zhao

2018-01-01

Full Text Available Background. Visceral hypersensitivity is a common feature of irritable bowel syndrome. Cholinergic system involves in the development of visceral hypersensitivity, and high-affinity choline transporter (CHT1 is of crucial importance in choline uptake system. However, involvement of CHT1 in visceral hypersensitivity remains unknown. The research aimed to study the CHT1 expression in dorsal root ganglions (DRGs and the role of CHT1 in visceral hypersensitivity. Methods. Repetitive water avoidance stress (WAS was used to induce visceral hypersensitivity in rats. Colorectal distension (CRD was determined, and the abdominal withdrawal reflex (AWR and threshold intensity data were recorded to measure the visceral sensitivity. After intraperitoneal injection of hemicholinium-3 (HC-3, the specific inhibitor of CHT1, CRD data were also recorded. The CHT1 expression of DRGs was investigated by Western blotting, immunohistochemistry, and quantitative RT-PCR. Acetylcholine levels in the DRGs were detected by the assay kit. Results. Repetitive WAS increased the AWR score of CRD at high distension pressure and decreased the mean threshold of rats. The CHT1 expression and acetylcholine concentration of DRG were significantly increased in WAS rats. After the administration of HC-3, the AWR score in WAS group was significantly increased at higher distension pressure while the threshold intensity was significantly reduced compared to the normal saline group. Acetylcholine concentration was significantly lower than the normal saline rats. Conclusion. Our research firstly reports that CHT1 is overexpressed in noninflammatory visceral hypersensitivity, and blockage of CHT1 can enhance the visceral hypersensitivity. CHT1 may play an inhibitory role in visceral hypersensitivity.

Expression of activation-induced cytidine deaminase gene in B lymphocytes of patients with common variable immunodeficiency.

Science.gov (United States)

Abolhassani, Hassan; Farrokhi, Amir Salek; Pourhamdi, Shabnam; Mohammadinejad, Payam; Sadeghi, Bamdad; Moazzeni, Seyed-Mohammad; Aghamohammadi, Asghar

2013-08-01

Common variable immunodeficiency (CVID) is a heterogeneous disorder characterized by reduced serum level of IgG, IgA or IgM and recurrent bacterial infections. Class switch recombination (CSR) as a critical process in immunoglobulin production is defective in a group of CVID patients. Activation-induced cytidine deaminase (AID) protein is an important molecule involving CSR process. The aim of this study was to investigate the AID gene mRNA production in a group of CVID patients indicating possible role of this molecule in this disorder. Peripheral blood mononuclear cells (PBMC) of 29 CVID patients and 21 healthy controls were isolated and stimulated by CD40L and IL-4 to induce AID gene expression. After 5 days AID gene mRNA production was investigated by real time polymerase chain reaction. AID gene was expressed in all of the studied patients. However the mean density of extracted AID mRNA showed higher level in CVID patients (230.95±103.04 ng/ml) rather than controls (210.00±44.72 ng/ml; P=0.5). CVID cases with lower level of AID had decreased total level of IgE (P=0.04) and stimulated IgE production (P=0.02); while cases with increased level of AID presented higher level of IgA (P=0.04) and numbers of B cells (P=0.02) and autoimmune disease (P=0.02). Different levels of AID gene expression may have important roles in dysregulation of immune system and final clinical presentation in CVID patients. Therefore investigating the expression of AID gene can help in classifying CVID patients.

Desempenho produtivo de tilápia do Nilo alimentada com níveis de colina na dieta = Growth performance of Nile tilapia fed graded choline levels in the diet

Directory of Open Access Journals (Sweden)

Ademir Calvo Fernandes Junior

2010-04-01

Full Text Available Este estudo foi realizado com o objetivo de avaliar o desempenho produtivo da tilápia do Nilo (Oreochromis niloticus alimentada com níveis de colina na dieta pelo período de 109 dias. Foram utilizados 192 alevinos com 4,0 ± 0,15 g de peso médio, distribuídos em 32 tanques-rede de 200 L, na densidade de seis peixes por tanque-rede, dispostos em aquários de 1.000 L. O delineamento experimental foi inteiramente casualizado com oito tratamentos e quatro repetições. As rações foram suplementadas com 0, 100, 200, 400, 600, 800, 1.000 e 1.200 mg de colina kg-1 de ração. Não foram observadas diferenças para ganho de peso, taxa de sobrevivência, conversão alimentar aparente, porcentagem de extrato etéreo do filé e do fígado, índice hepatossomático e concentração de lipídeos no plasma. Concluiuseque os diferentes níveis de colina não melhoraram o desempenho produtivo dos peixes nestas condições, pois a dieta basal supostamente supriu a exigência do peixe para colina.A 109-day feeding trial was undertaken aiming to evaluate the growth performance of Nile tilapia fed graded choline levels. One hundred and ninety-two (initial weight 4.0 ± 0.15 g fingerlings were distributed into 32 net cages (200 L each, four cages per treatmentand six fish per cage, placed in eight 1000L aquaria in a closed recirculation system. The treatments were assigned to the tanks comprising eight treatments and four replications arranged in a completely randomized experimental design. Diets were supplemented with choline chloride to provide 100, 200, 400, 600, 800, 1000, 1200 mg of choline per kg of feed and an unsupplemented diet. No significant differences were observed in growth performance, survival, apparent feed conversion, liver and fillet ether extract, hepatosomatic index and plasma lipid concentration, among treatments. Choline levels did not improve growth performance, possibly because the amount of choline in the diet had already met fish

NMR (1H and 13C) based signatures of abnormal choline metabolism in oral squamous cell carcinoma with no prominent Warburg effect

International Nuclear Information System (INIS)

Bag, Swarnendu; Banerjee, Deb Ranjan; Basak, Amit; Das, Amit Kumar; Pal, Mousumi; Banerjee, Rita; Paul, Ranjan Rashmi; Chatterjee, Jyotirmoy

2015-01-01

At functional levels, besides genes and proteins, changes in metabolome profiles are instructive for a biological system in health and disease including malignancy. It is understood that metabolomic alterations in association with proteomic and transcriptomic aberrations are very fundamental to unravel malignant micro-ambient criticality and oral cancer is no exception. Hence deciphering intricate dimensions of oral cancer metabolism may be contributory both for integrated appreciation of its pathogenesis and to identify any critical but yet unexplored dimension of this malignancy with high mortality rate. Although several methods do exist, NMR provides higher analytical precision in identification of cancer metabolomic signature. Present study explored abnormal signatures in choline metabolism in oral squamous cell carcinoma (OSCC) using 1 H and 13 C NMR analysis of serum. It has demonstrated down-regulation of choline with concomitant up-regulation of its break-down product in the form of trimethylamine N-oxide in OSCC compared to normal counterpart. Further, no significant change in lactate profile in OSCC possibly indicated that well-known Warburg effect was not a prominent phenomenon in such malignancy. Amongst other important metabolites, malonate has shown up-regulation but D-glucose, saturated fatty acids, acetate and threonine did not show any significant change. Analyzing these metabolomic findings present study proposed trimethyl amine N-oxide and malonate as important metabolic signature for oral cancer with no prominent Warburg effect. - Highlights: • NMR ( 1 H and 13 C) study of Oral Squamous cell Carcinoma Serum. • Abnormal Choline metabolomic signatures. • Up-regulation of Trimethylamine N-oxide. • Unchanged lactate profile indicates no prominent Warburg effect. • Proposed alternative glucose metabolism path through up-regulation of malonate

Restriction of Equine Infectious Anemia Virus by Equine APOBEC3 Cytidine Deaminases ▿ †

Science.gov (United States)

Zielonka, Jörg; Bravo, Ignacio G.; Marino, Daniela; Conrad, Elea; Perković, Mario; Battenberg, Marion; Cichutek, Klaus; Münk, Carsten

2009-01-01

The mammalian APOBEC3 (A3) proteins comprise a multigene family of cytidine deaminases that act as potent inhibitors of retroviruses and retrotransposons. The A3 locus on the chromosome 28 of the horse genome contains multiple A3 genes: two copies of A3Z1, five copies of A3Z2, and a single copy of A3Z3, indicating a complex evolution of multiple gene duplications. We have cloned and analyzed for expression the different equine A3 genes and examined as well the subcellular distribution of the corresponding proteins. Additionally, we have tested the functional antiretroviral activity of the equine and of several of the human and nonprimate A3 proteins against the Equine infectious anemia virus (EIAV), the Simian immunodeficiency virus (SIV), and the Adeno-associated virus type 2 (AAV-2). Hematopoietic cells of horses express at least five different A3s: A3Z1b, A3Z2a-Z2b, A3Z2c-Z2d, A3Z2e, and A3Z3, whereas circulating macrophages, the natural target of EIAV, express only part of the A3 repertoire. The five A3Z2 tandem copies arose after three consecutive, recent duplication events in the horse lineage, after the split between Equidae and Carnivora. The duplicated genes show different antiviral activities against different viruses: equine A3Z3 and A3Z2c-Z2d are potent inhibitors of EIAV while equine A3Z1b, A3Z2a-Z2b, A3Z2e showed only weak anti-EIAV activity. Equine A3Z1b and A3Z3 restricted AAV and all equine A3s, except A3Z1b, inhibited SIV. We hypothesize that the horse A3 genes are undergoing a process of subfunctionalization in their respective viral specificities, which might provide the evolutionary advantage for keeping five copies of the original gene. PMID:19458006

Supplementation with Folic Acid, but Not Creatine, Increases Plasma Betaine, Decreases Plasma Dimethylglycine, and Prevents a Decrease in Plasma Choline in Arsenic-Exposed Bangladeshi Adults123

Science.gov (United States)

Hall, Megan N; Liu, Xinhua; Caudill, Marie A; Malysheva, Olga; Ilievski, Vesna; Lomax-Luu, Angela M; Parvez, Faruque; Siddique, Abu B; Shahriar, Hasan; Uddin, Mohammad N; Islam, Tariqul; Graziano, Joseph H; Gamble, Mary V

2016-01-01

Background: Folic acid (FA) supplementation facilitates urinary excretion of arsenic, a human carcinogen. A better understanding of interactions between one-carbon metabolism intermediates may improve the ability to design nutrition interventions that further facilitate arsenic excretion. Objective: The objective was to determine if FA and/or creatine supplementation increase choline and betaine and decrease dimethylglycine (DMG). Methods: We conducted a secondary analysis of the Folic Acid and Creatine Trial, a randomized trial in arsenic-exposed Bangladeshi adults (n = 605, aged 24–55 y, 50.3% male) who received arsenic-removal water filters. We examined treatment effects of FA and/or creatine supplementation on plasma choline, betaine, and DMG concentrations, measured by LC–tandem mass spectrometry at baseline and at week 12. Group comparisons were between 1) 400 and 800 μg FA/d (FA400 and FA800, respectively) compared with placebo, 2) creatine (3 g/d) compared with placebo, and 3) creatine plus FA400 compared with FA400. Results: Choline decreased in the placebo group (−6.6%; 95% CI: −10.2%, −2.9%) but did not change in the FA groups (FA400: 2.5%; 95% CI: −0.9%, 6.1%; FA800: 1.4%; 95% CI: −2.5%, 5.5%; P DMG was greater in the FA groups (FA400: −26.7%; 95% CI: −30.9%, −22.2%; FA800: −27.8%; 95% CI: −31.8%, −23.4%) than in the placebo group (−12.3%; 95% CI: −18.1%, −6.2%; P DMG did not differ between creatine treatment arms and their respective reference groups. Conclusion: Supplementation for 12 wk with FA, but not creatine, increases plasma betaine, decreases plasma DMG, and prevents a decrease in plasma choline in arsenic-exposed Bangladeshi adults. This trial was registered at clinicaltrials.gov as NCT01050556. PMID:27052531

Change of choline compounds in sodium selenite-induced apoptosis of rats used as quantitative analysis by in vitro 9.4T MR spectroscopy

DEFF Research Database (Denmark)

Cao, Zhen; Wu, Lin-Ping; Li, Yun-Xia

2008-01-01

staining was employed to detect and confirm the change of liver cells. RESULTS: Good (1)H-MR spectra of perchloric acid extract from liver tissue of rats were obtained. The conventional metabolites were detected and assigned. Concentrations of different ingredient choline compounds in treatment group vs...

Temperature effects on the interaction mechanisms between the europium (III) and uranyl ions and zirconium diphosphate; Effets de la temperature sur les mecanismes d'interaction entre les ions europium (3) et uranyle et le diphosphate de zirconium

Energy Technology Data Exchange (ETDEWEB)

Finck, N

2006-10-15

Temperature should remain higher than 25 C in the near field environment of a nuclear waste repository for thousands years. In this context, the aim of this work is to study the temperature influence on the interaction mechanisms between europium (III) and uranyl ions and zirconium diphosphate, as well as the influence of a complexing medium (nitrate) on the sorption of the lanthanide. The experimental definition of the equilibria was achieved by combining a structural investigation with the macroscopic sorption data. Surface complexes were characterized at all temperatures (25 C to 90 C) by TRLFS experiments carried out on dry and in situ samples using an oven. This characterization was completed by XPS experiments carried out at 25 C on samples prepared at 25 C and 90 C. The reaction constants (surface hydration and cations sorption) were obtained by simulating the experimental data with the constant capacitance surface complexation model. The reaction constants temperature dependency allowed one to characterize thermodynamically the different reactions by application of the van't Hoff relation. The validity of this law was tested by performing microcalorimetric measurements of the sorption heat for both cations. (author)

Amyloid Beta Peptide 1-40 and the Function of Rat Hippocampal Hemicholinium-3 Sensitive Choline Carriers: Effects of a Proteolytic Degradation in Vitro

Czech Academy of Sciences Publication Activity Database

Krištofíková, Z.; Tejkalová, H.; Klaschka, Jan

2001-01-01

Roč. 26, č. 3 (2001), s. 203-212 ISSN 0364-3190 R&D Projects: GA MZd IZ3702 Institutional research plan: AV0Z1030915 Keywords : abeta * bromelain * papain * choline uptake * hemicholinium-3 * rat hippocampus Subject RIV: BB - Applied Statistics, Operational Research Impact factor: 1.638, year: 2001

Characterization of new eye drops with choline salicylate and assessment of their irritancy by in vitro short time exposure tests

OpenAIRE

Wroblewska, Katarzyna; Kucinska, Małgorzata; Murias, Marek; Lulek, Janina

2015-01-01

The aim of our study was to examine the irritation potential of new eye drops containing 2% choline salicylate (CS) as an active pharmaceutical ingredient (API) and various polymers increasing eye drop viscosity (hydroxyethylcellulose, hydroxypropyl methylcellulose, methylcellulose, polyvinyl alcohol, polyvinylpyrrolidone). The standard method for assessing the potential of irritating substances has been the Draize rabbit eye test. However the European Centre for Validation of Alternative Met...

Enhanced incorporation of fatty acid into phosphatidyl choline that parallels histamine discharge in mast cells

International Nuclear Information System (INIS)

Castle, J.D.; Castle, A.M.; Ma, A.K.; Stukenbrok, H.

1984-01-01

Purified rat peritoneal and pleural mast cells preincubated briefly with radioactively labeled fatty acid were treated with A23187, which bypasses primary receptors in stimulating exocytosis. An enhanced incorporation of fatty acid into phosphatidyl choline (PC) that occurred in parallel with histamine release at 24-25 degrees C was observed and was initially proportional to the total amount of histamine discharged. Enhanced PC labeling and histamine secretion were also proportional at temperatures ranging from 17-37 degrees C. Both radioactive linoleic and palmitic acids were incorporated selectively at the beta-position of the glycerol backbone of PC. PC labeling by [3H]choline was not detectably different in control and stimulated cells, and phosphatidic acid did not exhibit selectively enhanced beta-acylation. Thus, the stimulated labeling in A23187-treated cells may occur secondary to the action of a phospholipase A2 that favors PC as a substrate. Other peritoneal cell types exhibit a very similar A23187-stimulated selective labeling of PC. Therefore, autoradiography has been used to provide a direct demonstration that in purified preparations, mast cells are the principal cell type engaged in A23187-elicited incorporation of fatty acid into PC. The efficacy of this approach has relied on special procedures devised to obtain significantly different autoradiographic grain densities between control and stimulated preparations that can be attributed to differences in the level of [3H]palmitate-labeled PC. Preliminary tests using compound 48/80 as a secretory stimulus for mast cells have identified a similar selectively enhanced PC labeling. In either case, however, consideration of possible relationships between PC metabolism and the secretory process are premature since they have not been tested directly

Biphasic Elimination of Tenofovir Diphosphate and Nonlinear Pharmacokinetics of Zidovudine Triphosphate in a Microdosing Study

Science.gov (United States)

Chen, Jianmeng; Flexner, Charles; Liberman, Rosa G.; Skipper, Paul L.; Louissaint, Nicolette; Tannenbaum, Steven R.; Hendrix, Craig; Fuchs, Edward

2012-01-01

Objective Phase 0 studies can provide initial pharmacokinetics (PK) data in humans and help to facilitate early drug development, but their predictive value for standard dosing is controversial. To evaluate the prediction of microdosing for active intracellular drug metabolites, we compared the PK profile of two antiretroviral drugs, zidovudine (ZDV) and tenofovir (TFV), in microdose and standard dosing regimens. Study Design We administered a microdose (100 μg) of 14C-labeled drug (ZDV or tenofovir disoproxil fumarate (TDF)) with or without a standard unlabelled dose (300 mg) to healthy volunteers. Both the parent drug in plasma and the active metabolite, ZDV-triphosphate (ZDV-TP) or TFV-diphosphate (TFV-DP) in PBMCs and CD4+ cells were measured by AMS. Results The intracellular ZDV-TP concentration increased less than proportionally over the dose range studied (100 μg to 300 mg), while the intracellular TFV-DP PK were linear over the same dose range. ZDV-TP concentrations were lower in CD4+ cells versus total peripheral blood mononuclear cells (PBMCs), while TFV-DP concentrations were not different in CD4+ cells and PBMCs. Conclusion Our data were consistent with a rate-limiting step in the intracellular phosphorylation of ZDV but not TFV. AMS shows promise for predicting the PK of active intracellular metabolites of nucleosides, but nonlinearity of PK may be seen with some drugs. PMID:23187888

Detection of lymph node metastasis in patients with nodal prostate cancer relapse using (18)F/(11)C-choline positron emission tomography/computerized tomography.

Science.gov (United States)

Jilg, Cordula A; Schultze-Seemann, Wolfgang; Drendel, Vanessa; Vach, Werner; Wieser, Gesche; Krauss, Tobias; Jandausch, Anett; Hölz, Stefanie; Henne, Karl; Reske, Sven N; Grosu, Anca-L; Weber, Wolfgang A; Rischke, H Christian

2014-07-01

We evaluated the diagnostic accuracy of choline positron emission tomography/computerized tomography for nodal relapse of prostate cancer according to topographical site and tumor infiltration size in lymph nodes. A total of 72 patients with nodal prostate cancer relapse after primary therapy underwent pelvic and/or retroperitoneal salvage lymph node dissection. Salvage was done after whole body positron emission tomography/computerized tomography with (11)C-choline or (18)F-fluoroethylcholine showed positron emission tomography positive lymph nodes but no other detectable metastasis. Diagnostic accuracy was evaluated in 160 dissected lymph node regions (pelvic left/right and retroperitoneal), 498 subregions (common, external and internal iliac, obturator, presacral, aortic bifurcation, aortal, vena caval and interaortocaval) and 2,122 lymph nodes. Lymph node metastasis was present in 32% of resected lymph nodes (681 of 2,122), resulting in 238 positive subregions and 111 positive regions. Positron emission tomography/computerized tomography was positive for 110 regions and 209 subregions. Sensitivity, specificity, positive and negative predictive values, and accuracy were 91.9%, 83.7%, 92.7%, 82.0% and 89.4% (region based), 80.7%, 93.5%, 91.9%, 84.1% and 87.3% (subregion based), and 57.0%, 98.4%, 94.5%, 82.6% and 84.9% (lesion based), respectively. Of 393 positive lymph node metastases detected by this method 278 (70.7%) were in lymph nodes with a less than 10 mm short axis diameter. Imaging sensitivity was 13.3%, 57.4% and 82.8% for a tumor infiltration depth of 2 or greater to less than 3 mm, 5 or greater to less than 6 mm and 10 or greater to less than 11 mm, respectively. Lymph node metastasis site and the radiotracer ((11)C-choline/(18)F-fluoroethylcholine) had no substantial impact on diagnostic accuracy. Choline positron emission tomography/computerized tomography detects affected lymph node regions (pelvic left/right and retroperitoneal) in patients with

Influence of PSA, PSA velocity and PSA doubling time on contrast-enhanced 18F-choline PET/CT detection rate in patients with rising PSA after radical prostatectomy

International Nuclear Information System (INIS)

Schillaci, Orazio; Calabria, Ferdinando; Tavolozza, Mario; Caracciolo, Cristiana Ragano; Orlacchio, Antonio; Danieli, Roberta; Simonetti, Giovanni; Agro, Enrico Finazzi; Miano, Roberto

2012-01-01

To evaluate the accuracy of contrast-enhanced 18 F-choline PET/CT in restaging patients with prostate cancer after radical prostatectomy in relation to PSA, PSA velocity (PSAve) and PSA doubling time (PSAdt). PET/CT was performed in 49 patients (age range 58-87 years) with rising PSA (mean 4.13 ng/ml) who were divided in four groups according to PSA level: ≤1 ng/ml, 1 to ≤2 ng/ml, 2 to ≤4 ng/ml, and >4 ng/ml. PSAve and PSAdt were measured. PET and CT scans were interpreted separately and then together. PET/CT diagnosed relapse in 33 of the 49 patients (67%). The detection rates were 20%, 55%, 80% and 87% in the PSA groups ≤1, 1 to ≤2, 2 to ≤4 and >4 ng/ml, respectively. PET/CT was positive in 7 of 18 patients (38.9%) with a PSA ≤2 ng/ml, and in 26 of 31 (83.9%) with a PSA >2 ng/ml. PET/CT was positive in 7 of 25 patients (84%) with PSAdt ≤6 months, and in 12 of 24 patients (50%) with PSAdt >6 months, and was positive in 26 of 30 patients (86%) with a PSAve >2 ng/ml per year, and in 7 of 19 patients (36.8%) with PSAve ≤2 ng/ml per year. PET alone was positive in 31 of 49 patients (63.3%), and of these 31 patients, CT was negative in 14 but diagnosed bone lesions in 2 patients in whom PET alone was negative. CT with the administration of intravenous contrast medium did not provide any further information. Detection rate of 18 F-choline imaging is closely related to PSA and PSA kinetics. In particular, 18 F-choline PET/CT is recommended in patients with PSA >2 ng/ml, PSAdt ≤6 months and PSAve >2 ng/ml per year. CT is useful for detecting bone metastases that are not 18 F-choline-avid. The use of intravenous contrast agent seems unnecessary. (orig.)

Metabolic pathways promoting intrahepatic fatty acid accumulation in methionine and choline deficiency: implications for the pathogenesis of steatohepatitis.

Science.gov (United States)

Macfarlane, David P; Zou, Xiantong; Andrew, Ruth; Morton, Nicholas M; Livingstone, Dawn E W; Aucott, Rebecca L; Nyirenda, Moffat J; Iredale, John P; Walker, Brian R

2011-02-01

The pathological mechanisms that distinguish simple steatosis from steatohepatitis (or NASH, with consequent risk of cirrhosis and hepatocellular cancer) remain incompletely defined. Whereas both a methionine- and choline-deficient diet (MCDD) and a choline-deficient diet (CDD) lead to hepatic triglyceride accumulation, MCDD alone is associated with hepatic insulin resistance and inflammation (steatohepatitis). We used metabolic tracer techniques, including stable isotope ([¹³C₄]palmitate) dilution and mass isotopomer distribution analysis (MIDA) of [¹³C₂]acetate, to define differences in intrahepatic fatty acid metabolism that could explain the contrasting effect of MCDD and CDD on NASH in C57Bl6 mice. Compared with control-supplemented (CS) diet, liver triglyceride pool sizes were similarly elevated in CDD and MCDD groups (24.37 ± 2.4, 45.94 ± 3.9, and 43.30 ± 3.5 μmol/liver for CS, CDD, and MCDD, respectively), but intrahepatic neutrophil infiltration and plasma alanine aminotransferase (31 ± 3, 48 ± 4, 231 ± 79 U/l, P triglyceride pool differed between groups. Unlike CDD, MCDD had a defect in hepatic triglyceride export that was confirmed using intravenous tyloxapol (142 ± 21, 122 ± 15, and 80 ± 7 mg·kg⁻¹·h⁻¹, P metabolism may promote the development of steatohepatitis. Similar mechanisms may predispose to hepatocyte damage in human NASH.

Effect of adding different levels of rumen protected choline to the diet on productive and reproductive performance of female goats and growth of their kids from birthing to weaning.

Science.gov (United States)

Habeeb, Alsaied A; Gad, Ahmed E; Atta, Mostafa A; Mustafa, Mohammed M

2018-02-01

Forty female goats in the third parity were randomly divided into four similar groups. The experiment was started 20 days before mating and lasted until the end of the suckling period for 60 days and weaning their kids. The first group were fed diet without supplementation and kept as control while in the second, third and fourth groups, each doe was fed diets with rumen protected choline (RPC) at the rate of 10, 20 and 40 g/day, respectively. Results showed that number of doe kidding twins and triplets and litter weight of kids born per group increased with increasing the level of RPC in the diet of goats and viability rate of born kids during the suckling period improved due to RPC supplementation in the diets of their mothers. Duration of estrous, days from weaning to estrous, days from kidding to estrous and kidding interval decreased significantly, while conception rate increased due to adding RPC. Milk choline concentrations and total choline secretion though milk were progressively increased significantly with increasing the level of RPC supplementation. Live body weight and daily body gain of their suckling male and female kids at weaning increased significantly with increasing RPC levels in the diets of their mothers. © 2017 Japanese Society of Animal Science.

Phospholipids chiral at phosphorus. Dramatic effects of phosphorus chirality on the deuterium NMR properties of the choline head group of phospholipids in the liquid crystalline phase

International Nuclear Information System (INIS)

Loffredo, W.M.; Jiang, Rutai; Tsai, Mingdaw

1990-01-01

To probe the motional and conformational propertis of the choline head group of 1,2-dipalmitoyl-sn-glycero-3-thiophosphocholine (DPPsC), the R p , S p , and R p + S p isomers of [α-D 2 ]DPPsC, [β-D 2 ]DPPsC, and [δ-D 9 ]DPPsC in the subgel, gel, and liquid crystalline phases were investigated with deuterium NMR, and the results were compared with those of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) labeled at the same positions. In the subgel phase (5 degree C) all isomers of [α-D 2 ]DPPsC and [β-D 2 ]DPPsC displayed amorphous line shapes characteristic of a restricted and disordered motional environment, whereas [δ-D 9 ]DPPsC showed narrower and symmetric line shapes indicating substantial motions. For all three labeled positions the apparent line width of the R p isomer is larger than those of S p and R p + S p isomers, and the amorphous line shape of the R p isomer also persists at 25 and 35 degree C. These results indicate that the motional and conformational properties of the C α -C β segment of DPPsC is very sensitive to the configuration at phosphorus. Structurally, this provides strong support for noncovalent interactions between the quaternary ammonium group of choline and the phosphate group of a neighboring molecule in the bilayers of phosphatidylcholine and suggests that such interactions are important to the motion of the choline chain

Synthesis, molecular docking, DFT calculations and cytotoxicity activity of benzo[g]quinazoline derivatives in choline chloride-urea

Science.gov (United States)

Lakshmanan, Sivalingam; Govindaraj, Dharman; Ramalakshmi, Narayanan; Antony, S. Arul

2017-12-01

Green and highly efficient one-pot three component approach for the synthesis of benzo[g]quinazoline derivatives (6a-g) using Choline chloride-urea (DES). Synthesized compounds 6b and 6g showed the most potent biological activity against A549 lung cancer cell line. Docking simulation was performed to position compounds 6b and 6g showed the greater affinity for anaplastic lymphoma kinase (ALK) receptor. Quantum chemical studies were carried out on these compounds to understand the structural features essential for activity using DFT/6-31G level of theory.

The Semi-automatic Synthesis of 18F-fluoroethyl-choline by Domestic FDG Synthesizer

Directory of Open Access Journals (Sweden)

ZHOU Ming

2016-02-01

Full Text Available As an important complementary imaging agent for 18F-FDG, 18F-fluoroethyl-choline (18F-FECH has been demonstrated to be promising in brain and prostate cancer imaging. By using domestic PET-FDG-TI-I CPCU synthesizer, 18F-FECH was synthesized by different reagents and consumable supplies. The C18 column was added before the product collection bottle to remove K2.2.2. The 18F-FECH was synthesized by PET-FDG-IT-I synthesizer efficiently about 30 minutes by radiochemical yield of 42.0% (no decay corrected, n=5, and the radiochemical purity was still more than 99.0% after 6 hours. The results showed the domestic PET-FDG-IT-I synthesizer could semi-automatically synthesize injectable 18F-FECH in high efficiency and radiochemical purity

Visual evoked potentials (VEP and visual acuity improvement after cytidine 52 -diphosphocholine (CDP-Choline therapy in amblyopic patient

Directory of Open Access Journals (Sweden)

Regina Halfeld Furtado de Mendonça

2012-10-01

Full Text Available Citicoline may be used in many neurological disorders. Combined treatment of citicoline with patching in amblyopia has previously been researched. The purpose of this paper is to illustrate the effect of citicoline in non-patching amblyopic patient. A 11-year-old amblyopic boy underwent complete ophthalmological examinations, including VEP with flash and pattern stimulus. Two averages of 100 sweep were performed for flash stimulus. Pattern reversal stimulus obtained with high contrast was performed with 60', 30' and 15' checks stimuli. The VEP was repeated 90 days later after a therapy with citicoline and vitamin and the results compared with the responses of the previous recording session. The visual acuity (VA was 0,7 in the RE and 1,0 in the LE. The VEP pattern amplitude was normal in both eyes. Delayed in latency was detected for all spatial frequency stimulus (SFS in the RE. Delay in latency was detected only for high SFS in the LE. After the treatment, the VA was 1,0 in both eyes. The latency was normalized with low SFS on the RE and with high SFS on the LE. The flash VEP was normal before and after the therapy. In conclusion, the citicoline demonstrated that it was effective in the treatment of amblyopic eye without patching. The VA and the VEP latency improvement demonstrated that the citicoline enhance the transmission of the electric impulse from retina to visual cortex. Further research is required to understand the immediate and long-term effect of coline treatment in amblyopic patients.

Patterns of Direct Projections from the Hippocampus to the Medial Septum-Diagonal Band Complex : Anterograde Tracing with Phaseolus vulgaris Leucoagglutinin Combined with Immunohistochemistry of Choline Acetyltransferase

NARCIS (Netherlands)

Gaykema, R.P.A.; Kuil, J. van der; Hersh, L.B.; Luiten, P.G.M.

1991-01-01

The projections from the Ammon's horn to the cholinergic cell groups in the medial septal and diagonal band nuclei were investigated with anterograde tracing of Phaseolus vulgaris leucoagglutinin combined with immunocytochemical detection of choline acetyltransferase, in the rat. Tracer injections

Activation of functional α7-containing nAChRs in hippocampal CA1 pyramidal neurons by physiological levels of choline in the presence of PNU-120596.

Directory of Open Access Journals (Sweden)

Bopanna I Kalappa

2010-11-01

Full Text Available The level of expression of functional α7-containing nicotinic acetylcholine receptors (nAChRs in hippocampal CA1 pyramidal neurons is believed to be very low compared to hippocampal CA1 interneurons, and for many years this expression was largely overlooked. However, high densities of expression of functional α7-containing nAChRs in CA1 pyramidal neurons may not be necessary for triggering important cellular and network functions, especially if activation of α7-containing nAChRs occurs in the presence of positive allosteric modulators such as PNU-120596.An approach previously developed for α7-containing nAChRs expressed in tuberomammillary neurons was applied to investigate functional CA1 pyramidal α7-containing nAChRs using rat coronal hippocampal slices and patch-clamp electrophysiology. The majority (∼71% of tested CA1 pyramidal neurons expressed low densities of functional α7-containing nAChRs as evidenced by small whole-cell responses to choline, a selective endogenous agonist of α7 nAChRs. These responses were potentiated by PNU-120596, a novel positive allosteric modulator of α7 nAChRs. The density of functional α7-containing nAChRs expressed in CA1 pyramidal neurons (and thus, the normalized net effect of activation, i.e., response net charge per unit of membrane capacitance per unit of time was estimated to be ∼5% of the density observed in CA1 interneurons. The results of this study demonstrate that despite low levels of expression of functional pyramidal α7-containing nAChRs, physiological levels of choline (∼10 µM are sufficient to activate these receptors and transiently depolarize and even excite CA1 pyramidal neurons in the presence of PNU-120596. The observed effects are possible because in the presence of 10 µM choline and 1-5 µM PNU-120596, a single opening of an individual pyramidal α7-containing nAChR ion channel appears to transiently depolarize (∼4 mV the entire pyramidal neuron and occasionally

NMR ({sup 1}H and {sup 13}C) based signatures of abnormal choline metabolism in oral squamous cell carcinoma with no prominent Warburg effect

Energy Technology Data Exchange (ETDEWEB)

Bag, Swarnendu, E-mail: Swarna.bag@gmail.com [School of Medical Science and Technology, Indian Institute of Technology-Kharagpur, 721302 West Bengal (India); Banerjee, Deb Ranjan, E-mail: debranjan2@gmail.com [Department of Chemistry, Indian Institute of Technology-Kharagpur, 721302 West Bengal (India); Basak, Amit, E-mail: absk@chem.iitkgp.ernet.in [Department of Chemistry, Indian Institute of Technology-Kharagpur, 721302 West Bengal (India); Das, Amit Kumar, E-mail: amitk@hijli.iitkgp.ernet.in [Department of Biotechnology, Indian Institute of Technology-Kharagpur, 721302 West Bengal (India); Pal, Mousumi, E-mail: drmpal62@gmail.com [Department of Oral and Maxillofacial Pathology, Guru Nanak Institute of Dental Sciences and Research, Kolkata, West Bengal (India); Banerjee, Rita, E-mail: ritabanerjee@outlook.com [Department of Science and Technology, New Mehrauli Road, New Delhi 110016 (India); Paul, Ranjan Rashmi, E-mail: dr_rsspaul@yahoo.co.in [Department of Oral and Maxillofacial Pathology, Guru Nanak Institute of Dental Sciences and Research, Kolkata, West Bengal (India); Chatterjee, Jyotirmoy, E-mail: jchatterjee.iitkgp@gmail.com [School of Medical Science and Technology, Indian Institute of Technology-Kharagpur, 721302 West Bengal (India)

2015-04-17

At functional levels, besides genes and proteins, changes in metabolome profiles are instructive for a biological system in health and disease including malignancy. It is understood that metabolomic alterations in association with proteomic and transcriptomic aberrations are very fundamental to unravel malignant micro-ambient criticality and oral cancer is no exception. Hence deciphering intricate dimensions of oral cancer metabolism may be contributory both for integrated appreciation of its pathogenesis and to identify any critical but yet unexplored dimension of this malignancy with high mortality rate. Although several methods do exist, NMR provides higher analytical precision in identification of cancer metabolomic signature. Present study explored abnormal signatures in choline metabolism in oral squamous cell carcinoma (OSCC) using {sup 1}H and {sup 13}C NMR analysis of serum. It has demonstrated down-regulation of choline with concomitant up-regulation of its break-down product in the form of trimethylamine N-oxide in OSCC compared to normal counterpart. Further, no significant change in lactate profile in OSCC possibly indicated that well-known Warburg effect was not a prominent phenomenon in such malignancy. Amongst other important metabolites, malonate has shown up-regulation but D-glucose, saturated fatty acids, acetate and threonine did not show any significant change. Analyzing these metabolomic findings present study proposed trimethyl amine N-oxide and malonate as important metabolic signature for oral cancer with no prominent Warburg effect. - Highlights: • NMR ({sup 1}H and {sup 13}C) study of Oral Squamous cell Carcinoma Serum. • Abnormal Choline metabolomic signatures. • Up-regulation of Trimethylamine N-oxide. • Unchanged lactate profile indicates no prominent Warburg effect. • Proposed alternative glucose metabolism path through up-regulation of malonate.

Influence of PSA, PSA velocity and PSA doubling time on contrast-enhanced {sup 18}F-choline PET/CT detection rate in patients with rising PSA after radical prostatectomy

Energy Technology Data Exchange (ETDEWEB)

Schillaci, Orazio [University ' ' Tor Vergata' ' , Department of Biopathology and Diagnostic Imaging, Interventional, Rome (Italy); IRCCS Neuromed, Department of Nuclear Medicine and Molecular Imaging, Pozzilli (Italy); Calabria, Ferdinando [IRCCS Neuromed, Department of Nuclear Medicine and Molecular Imaging, Pozzilli (Italy); Tavolozza, Mario; Caracciolo, Cristiana Ragano; Orlacchio, Antonio; Danieli, Roberta; Simonetti, Giovanni [University ' ' Tor Vergata' ' , Department of Biopathology and Diagnostic Imaging, Interventional, Rome (Italy); Agro, Enrico Finazzi; Miano, Roberto [University Hospital ' ' Tor Vergata' ' , Department of Urology, Rome (Italy)

2012-04-15

To evaluate the accuracy of contrast-enhanced {sup 18}F-choline PET/CT in restaging patients with prostate cancer after radical prostatectomy in relation to PSA, PSA velocity (PSAve) and PSA doubling time (PSAdt). PET/CT was performed in 49 patients (age range 58-87 years) with rising PSA (mean 4.13 ng/ml) who were divided in four groups according to PSA level: {<=}1 ng/ml, 1 to {<=}2 ng/ml, 2 to {<=}4 ng/ml, and >4 ng/ml. PSAve and PSAdt were measured. PET and CT scans were interpreted separately and then together. PET/CT diagnosed relapse in 33 of the 49 patients (67%). The detection rates were 20%, 55%, 80% and 87% in the PSA groups {<=}1, 1 to {<=}2, 2 to {<=}4 and >4 ng/ml, respectively. PET/CT was positive in 7 of 18 patients (38.9%) with a PSA {<=}2 ng/ml, and in 26 of 31 (83.9%) with a PSA >2 ng/ml. PET/CT was positive in 7 of 25 patients (84%) with PSAdt {<=}6 months, and in 12 of 24 patients (50%) with PSAdt >6 months, and was positive in 26 of 30 patients (86%) with a PSAve >2 ng/ml per year, and in 7 of 19 patients (36.8%) with PSAve {<=}2 ng/ml per year. PET alone was positive in 31 of 49 patients (63.3%), and of these 31 patients, CT was negative in 14 but diagnosed bone lesions in 2 patients in whom PET alone was negative. CT with the administration of intravenous contrast medium did not provide any further information. Detection rate of {sup 18}F-choline imaging is closely related to PSA and PSA kinetics. In particular, {sup 18}F-choline PET/CT is recommended in patients with PSA >2 ng/ml, PSAdt {<=}6 months and PSAve >2 ng/ml per year. CT is useful for detecting bone metastases that are not {sup 18}F-choline-avid. The use of intravenous contrast agent seems unnecessary. (orig.)

Expression of human choline kinase in NIH 3T3 fibroblasts increases the mitogenic potential of insulin and insulin-like growth factor I.

Science.gov (United States)

Chung, T; Huang, J S; Mukherjee, J J; Crilly, K S; Kiss, Z

2000-05-01

In mammalian cells, growth factors, oncogenes, and carcinogens stimulate phosphocholine (PCho) synthesis by choline kinase (CK), suggesting that PCho may regulate cell growth. To validate the role of PCho in mitogenesis, we determined the effects of insulin, insulin-like growth factor I (IGF-I), and other growth factors on DNA synthesis in NIH 3T3 fibroblast sublines highly expressing human choline kinase (CK) without increasing phosphatidylcholine synthesis. In serum-starved CK expressor cells, insulin and IGF-I stimulated DNA synthesis, p70 S6 kinase (p70 S6K) activity, phosphatidylinositol 3-kinase (PI3K) activity, and activating phosphorylation of p42/p44 mitogen-activated protein kinases (MAPK) to greater extents than in the corresponding vector control cells. Furthermore, the CK inhibitor hemicholinium-3 (HC-3) inhibited insulin- and IGF-I-induced DNA synthesis in the CK overexpressors, but not in the vector control cells. The results indicate that high cellular levels of PCho potentiate insulin- and IGF-I-induced DNA synthesis by MAPK- and p70 S6K-regulated mechanisms.

Impact of total PSA, PSA doubling time and PSA velocity on detection rates of 11C-Choline positron emission tomography in recurrent prostate cancer

NARCIS (Netherlands)

Rybalov, Maxim; Breeuwsma, Anthonius J.; Leliveld, Anna M.; Pruim, Jan; Dierckx, Rudi A.; de Jong, Igle J.

PURPOSE: To evaluate the effect of total PSA (tPSA) and PSA kinetics on the detection rates of (11)C-Choline PET in patients with biochemical recurrence (BCR) after radical prostatectomy (RP) or external beam radiotherapy (EBRT). METHODS: We included 185 patients with BCR after RP (PSA >0.2 ng/ml)

Choline Supplementation Prevents a Hallmark Disturbance of Kwashiorkor in Weanling Mice Fed a Maize Vegetable Diet: Hepatic Steatosis of Undernutrition

OpenAIRE

Thaddaeus May; Kevin C. Klatt; Jacob Smith; Eumenia Castro; Mark Manary; Marie A. Caudill; Farook Jahoor; Marta L. Fiorotto

2018-01-01

Hepatic steatosis is a hallmark feature of kwashiorkor malnutrition. However, the pathogenesis of hepatic steatosis in kwashiorkor is uncertain. Our objective was to develop a mouse model of childhood undernutrition in order to test the hypothesis that feeding a maize vegetable diet (MVD), like that consumed by children at risk for kwashiorkor, will cause hepatic steatosis which is prevented by supplementation with choline. A MVD was developed with locally sourced organic ingredients, and fed...

Implications of secondary structure prediction and amino acid sequence comparison of class I and class II phosphoribosyl diphosphate synthases on catalysis, regulation, and quaternary structure

DEFF Research Database (Denmark)

Krath, B N; Hove-Jensen, B

2001-01-01

Spinach 5-phospho-D-ribosyl alpha-1-diphosphate (PRPP) synthase isozyme 4 was synthesized in Escherichia coli and purified to near homogeneity. The activity of the enzyme is independent of P(i); it is inhibited by ADP in a competitive manner, indicating a lack of an allosteric site; and it accepts...... is consistent with a homotrimer. Secondary structure prediction shows that spinach PRPP synthase isozyme 4 has a general folding similar to that of Bacillus subtilis class I PRPP synthase, for which the three-dimensional structure has been solved, as the position and extent of helices and beta-sheets of the two...... in the spinach enzyme. In contrast, residues of the active site of B. subtilis PRPP synthase show extensive conservation in spinach PRPP synthase isozyme 4....

Supplementation with rumen-protected methionine or choline during the transition period influences whole-blood immune response in periparturient dairy cows.

Science.gov (United States)

Vailati-Riboni, M; Zhou, Z; Jacometo, C B; Minuti, A; Trevisi, E; Luchini, D N; Loor, J J

2017-05-01

Methionine, together with Lys, is the most limiting AA for milk production in dairy cows. Besides its crucial role in milk production, Met and its derivate metabolites (e.g., glutathione, taurine, polyamines) are well-known immunonutrients in nonruminants, helping support and boost immune function and activity. In the present study, the effects of Met or choline, as its precursor, were investigated using an ex vivo whole blood challenge. The study involved 33 multiparous Holstein cows (from a larger cohort with a factorial arrangement of treatments) assigned from d -21 to +30 relative to parturition to a basal control (CON) diet, CON plus rumen-protected Met (MET, Smartamine M, Adisseo NA, Alpharetta, GA) at a rate of 0.08% of dry matter, or CON plus rumen-protected choline (CHOL, ReaShure, Balchem Inc., New Hampton, NY) at 60 g/d. Blood was sampled on d -15, -7, 2, 7, and 20 for ex vivo lipopolysaccharide (LPS) challenge, and on d 1, 4, 14, and 28 relative to parturition for phagocytosis and oxidative burst assays. The MET cows had greater energy-corrected milk production and milk protein content. Overall, IL-6 response to LPS increased around parturition, whereas IL-1β remained constant, casting doubt on the existence of systemic immunosuppression in the peripartal period. Supplementation with MET dampened the postpartal blood response to LPS (lower IL-1β), while improving postpartum neutrophil and monocyte phagocytosis capacity and oxidative burst activity. In contrast, CHOL supplementation increased monocyte phagocytosis capacity. Overall, the data revealed a peripartal immune hyper-response, which appeared to have been mitigated by MET supplementation. Both MET and CHOL effectively improved immune function; however, MET affected the immune and antioxidant status before parturition, which might have been beneficial to prepare the cow to respond to metabolic challenges after parturition. These results provide insights on potential differences in the

18F-Choline Positron Emission Tomography/Computed Tomography–Driven High-Dose Salvage Radiation Therapy in Patients With Biochemical Progression After Radical Prostatectomy: Feasibility Study in 60 Patients

International Nuclear Information System (INIS)

D'Angelillo, Rolando M.; Sciuto, Rosa; Ramella, Sara; Papalia, Rocco; Jereczek-Fossa, Barbara A.; Trodella, Luca E.; Fiore, Michele; Gallucci, Michele; Maini, Carlo L.; Trodella, Lucio

2014-01-01

Purpose: To retrospectively review data of a cohort of patients with biochemical progression after radical prostatectomy, treated according to a uniform institutional treatment policy, to evaluate toxicity and feasibility of high-dose salvage radiation therapy (80 Gy). Methods and Materials: Data on 60 patients with biochemical progression after radical prostatectomy between January 2009 and September 2011 were reviewed. The median value of prostate-specific antigen before radiation therapy was 0.9 ng/mL. All patients at time of diagnosis of biochemical recurrence underwent dynamic 18 F-choline positron emission tomography/computed tomography (PET/CT), which revealed in all cases a local recurrence. High-dose salvage radiation therapy was delivered up to total dose of 80 Gy to 18F-choline PET/CT-positive area. Toxicity was recorded according to the Common Terminology Criteria for Adverse Events, version 3.0, scale. Results: Treatment was generally well tolerated: 54 patients (90%) completed salvage radiation therapy without any interruption. Gastrointestinal grade ≥2 acute toxicity was recorded in 6 patients (10%), whereas no patient experienced a grade ≥2 genitourinary toxicity. No grade 4 acute toxicity events were recorded. Only 1 patient (1.7%) experienced a grade 2 gastrointestinal late toxicity. With a mean follow-up of 31.2 months, 46 of 60 patients (76.6%) were free of recurrence. The 3-year biochemical progression-free survival rate was 72.5%. Conclusions: At early follow-up, 18 F-choline PET/CT-driven high-dose salvage radiation therapy seems to be feasible and well tolerated, with a low rate of toxicity

Thiamin diphosphate-dependent enzymes: from enzymology to metabolic regulation, drug design and disease models.

Science.gov (United States)

Bunik, Victoria I; Tylicki, Adam; Lukashev, Nikolay V

2013-12-01

Bringing a knowledge of enzymology into research in vivo and in situ is of great importance in understanding systems biology and metabolic regulation. The central metabolic significance of thiamin (vitamin B1 ) and its diphosphorylated derivative (thiamin diphosphate; ThDP), and the fundamental differences in the ThDP-dependent enzymes of metabolic networks in mammals versus plants, fungi and bacteria, or in health versus disease, suggest that these enzymes are promising targets for biotechnological and medical applications. Here, the in vivo action of known regulators of ThDP-dependent enzymes, such as synthetic structural analogs of the enzyme substrates and thiamin, is analyzed in light of the enzymological data accumulated during half a century of research. Mimicking the enzyme-specific catalytic intermediates, the phosphonate analogs of 2-oxo acids selectively inhibit particular ThDP-dependent enzymes. Because of their selectivity, use of these compounds in cellular and animal models of ThDP-dependent enzyme malfunctions improves the validity of the model and its predictive power when compared with the nonselective and enzymatically less characterized oxythiamin and pyrithiamin. In vitro studies of the interaction of thiamin analogs and their biological derivatives with potential in vivo targets are necessary to identify and attenuate the analog selectivity. For both the substrate and thiamin synthetic analogs, in vitro reactivities with potential targets are highly relevant in vivo. However, effective concentrations in vivo are often higher than in vitro studies would suggest. The significance of specific inihibition of the ThDP-dependent enzymes for the development of herbicides, antibiotics, anticancer and neuroprotective strategies is discussed. © 2013 FEBS.

Crystallization and preliminary X-ray analysis of formate oxidase, an enzyme of the glucose–methanol–choline oxidoreductase family

International Nuclear Information System (INIS)

Maeda, Yoshifumi; Doubayashi, Daiju; Ootake, Takumi; Oki, Masaya; Mikami, Bunzo; Uchida, Hiroyuki

2010-01-01

Formate oxidase from A. oryzae RIB40 was crystallized and diffraction data were collected to a resolution of 2.4 Å. Formate oxidase (FOD), which catalyzes the oxidation of formate to yield carbon dioxide and hydrogen peroxide, belongs to the glucose–methanol–choline oxidoreductase (GMCO) family. FOD from Aspergillus oryzae RIB40, which has a modified FAD as a cofactor, was crystallized at 293 K by the hanging-drop vapour-diffusion method. The crystal was orthorhombic and belonged to space group C222 1 . Diffraction data were collected from a single crystal to 2.4 Å resolution

Colina e betaína em rações purificadas na nutrição da tilápia do Nilo (Oreochromis niloticus Choline and betaine in purified diets for Nile tilapia (Oreochromis niloticus

Directory of Open Access Journals (Sweden)

Ivan Vieira

2001-12-01

Full Text Available Problemas metabólicos observados em produções intensivas de tilápias do Nilo (Oreochromis niloticus têm sido relacionados à deficiência de colina nas rações. Com o objetivo de avaliar o efeito da suplementação dietética da colina na nutrição da espécie, rações purificadas contendo 0; 375; 750; 1.125; 1.500 ou 1.875 mg de cloreto de colina por kg, foram administradas ad libitum por 42 dias a tilápias do Nilo (5,09 ± 0,14 g, estocados em gaiolas de PVC atóxico (volume = 60 L, alojadas em caixas de polipropileno de 1000 L, em ambiente com condições controladas de temperatura e luminosidade, num delineamento experimental em blocos incompletos casualizados, com três parcelas por bloco (n=5. O ganho de peso (GDP e o índice de conversão alimentar (ICA de todos os tratamentos foram superiores ao controle. Não foram observadas diferenças para a quantidade de lipídios no fígado e tecido corporal, e sobrevivência (S%. Num segundo experimento, os peixes foram alimentados com rações suplementadas com 1.250 ou 2.500 mg de cloreto de colina por kg; ou 1.000; 2.000 ou 3.000 mg de betaína por kg. Não foram observadas diferenças significativas para S% e acúmulo de lipídeos hepáticos ou corporais; o ICA e GDP dos tratamentos suplementados com colina foram superiores aos dos tratamentos suplementados com betaína, mas não diferiram entre si. Níveis de suplementação superiores a 375 mg de cloreto de colina por kg de alimento melhoram o ICA e o GDP da tilápia do Nilo, mas a betaína não substitui efetivamente a colina em rações para a espécie.Metabolic problems detected in intensively raised Nile tilapia (Oreochromis niloticus are credited to possible sub-supplementation of coline in commercial feeds. To investigate the utilization of choline and betaine as feed supplement for the Nile tilapia, groups of 10 fingerlings (5.09 ± 0.14 g stocked in 30 PVC cages (60 L, kept under controlled environmental conditions inside

Study of the irradiation effects on thorium phosphate diphosphate ({beta}-TPD): consequences on its chemical durability; Etude des effets d'irradiation sur le phosphate diphosphate de thorium ({beta}-PDT): consequences sur la durabilite chimique

Energy Technology Data Exchange (ETDEWEB)

Tamain, C

2005-12-15

Since Thorium Phosphate Diphosphate (beta-TPD) can be considered as a potential host matrix for long-term storage in underground repository, it is necessary to study the irradiation effects on the structure of this ceramics and the consequences on its chemical durability. Sintered samples of beta-TPD and of associated solid solutions of beta-TUPD were irradiated under ion beams and then altered in aqueous solutions. Depending on the electronic LET value, beta-TPD can be completely or partly amorphized. Furthermore, the ability of recrystallization of the amorphous material by thermal annealing was also demonstrated. Some leaching tests, realized on these irradiated samples, have shown a significant effect of the amorphous fraction on the normalized dissolution rate which was increased by a factor of 10 from the crystallized to the fully amorphized material. Correlatively, the amorphous fraction also modified the delay to reach the saturation conditions associated to the thermodynamic equilibria involved. On the other hand, it exhibited no influence neither on other kinetic parameters, such as activation energy of the dissolution process or partial order related to the proton concentration, nor on the nature of the neo-formed phase formed at the saturation of the leachate and identified as Thorium Phosphate Hydrogeno-Phosphate Hydrate (TPHPH). Beta-TUPD samples were also irradiated by gamma and alpha rays during leaching tests to study the effects of radiolysis in the leaching medium on the normalized leaching rate. It appeared that the radiolytic species occurring in the dissolution mechanism were unstable, disappearing quickly when stopping the irradiation. (author)

Fibrillin 5 Is Essential for Plastoquinone-9 Biosynthesis by Binding to Solanesyl Diphosphate Synthases in Arabidopsis

Science.gov (United States)

Kim, Eun-Ha; Lee, Yongjik

2015-01-01

Fibrillins are lipid-associated proteins in plastids and are ubiquitous in plants. They accumulate in chromoplasts and sequester carotenoids during the development of flowers and fruits. However, little is known about the functions of fibrillins in leaf tissues. Here, we identified fibrillin 5 (FBN5), which is essential for plastoquinone-9 (PQ-9) biosynthesis in Arabidopsis thaliana. Homozygous fbn5-1 mutations were seedling-lethal, and XVE:FBN5-B transgenic plants expressing low levels of FBN5-B had a slower growth rate and were smaller than wild-type plants. In chloroplasts, FBN5-B specifically interacted with solanesyl diphosphate synthases (SPSs) 1 and 2, which biosynthesize the solanesyl moiety of PQ-9. Plants containing defective FBN5-B accumulated less PQ-9 and its cyclized product, plastochromanol-8, but the levels of tocopherols were not affected. The reduced PQ-9 content of XVE:FBN5-B transgenic plants was consistent with their lower photosynthetic performance and higher levels of hydrogen peroxide under cold stress. These results indicate that FBN5-B is required for PQ-9 biosynthesis through its interaction with SPS. Our study adds FBN5 as a structural component involved in the biosynthesis of PQ-9. FBN5 binding to the hydrophobic solanesyl moiety, which is generated by SPS1 and SPS2, in FBN5-B/SPS homodimeric complexes stimulates the enzyme activity of SPS1 and SPS2. PMID:26432861

Effects of choline chloride on electrodeposited Ni coating from a Watts-type bath

Science.gov (United States)

Wang, Yurong; Yang, Caihong; He, Jiawei; Wang, Wenchang; Mitsuzak, Naotoshi; Chen, Zhidong

2016-05-01

Electrodeposition of bright nickel (Ni) was carried out in a Watts-type bath. Choline chloride (ChCl) was applied as a multifunctional additive and substitute for nickel chloride (NiCl2) in a Watts-type bath. The function of ChCl was investigated through conductivity tests, anodic polarization, and cathodic polarization experiments. The studies revealed that ChCl performed well as a conducting salt, anodic activator, and cathodic inhibitor. The effects of ChCl on deposition rate, preferred orientation, grain size, surface morphology, and microhardness of Ni coatings were also studied. The deposition rate reached a maximum value of greater than 27 μm h-1 when 20 g L-1 ChCl was introduced to the bath. Using X-ray diffraction, it was confirmed that progressive addition of ChCl promoted the preferred crystal orientation modification from (2 0 0) and (2 2 0) to (1 1 1), refined grain size, and enhanced microhardness. The presence of ChCl lowered the roughness of the coating.