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Sample records for additional arginine residues

  1. Chemical modification of arginine residues in the lactose repressor

    International Nuclear Information System (INIS)

    Whitson, P.A.; Matthews, K.S.

    1987-01-01

    The lactose repressor protein was chemically modified with 2,3-butanedione and phenylglyoxal. Arginine reaction was quantitated by either amino aced analysis or incorporation of 14 C-labeled phenylglyoxal. Inducer binding activity was unaffected by the modification of arginine residues, while both operator and nonspecific DNA binding activities were diminished, although to differing degrees. The correlation of the decrease in DNA binding activities with the modification of ∼ 1-2 equiv of arginine per monomer suggests increased reactivity of a functionally essential residue(s). For both reagents, operator DNA binding activity was protected by the presence of calf thymus DNA, and the extent of reaction with phenylglyoxal was simultaneously diminished. This protection presumably results from steric restriction of reagent access to an arginine(s) that is (are) essential for DNA binding interactions. These experiments suggest that there is (are) an essential reactive arginine(s) critical for repressor binding to DNA

  2. Effects of arginine and phytogenic additive supplementation on performance and health of brown-egg layers

    Directory of Open Access Journals (Sweden)

    Vitor Barbosa Fascina

    Full Text Available ABSTRACT This study was performed to evaluate the effects of the association of different digestible arginine and phytogenic additive dietary levels on performance and health status of brown-egg layers. In this study, a total of 504 33-week-old Hisex Brown layers were distributed into a completely randomized experimental design to a 4 × 3 factorial arrangement (dietary digestible arginine levels: 880, 968, 1056, or 1144 mg/kg of feed × phytogenic additive levels: 0, 100, and 200 mg/kg of feed with six replicate cages of seven birds per cage. The phytogenic additive was composed of extracts of Baccharis dracunculifolia (40%, Astragalus membranaceus lipopolysaccharides (20%, cinnamon, and grape seed (20%. Feed intake was reduced when diets containing 1056 mg of arginine were supplemented with 100 or 200 mg phytogenic additive per kg. Feed conversion ratio was improved when diets were supplemented with 100 mg of phytogenic additive or with 1056 mg of arginine per kg of feed. Egg mass was increased when diets were supplemented with 1056 mg arginine per kg of feed. Arginine supplementation quadratically increased albumen percentage and reduced yolk percentage. Higher arginine and phytogenic additive levels reduced heterophyl:lymphocyte ratio and blood uric acid, total cholesterol, very-low density lipoprotein, and triglyceride levels. Dietary supplementation of 100 mg of phytogenic additive associated with high arginine levels increased nitric oxide production by peritoneal macrophages and 1056 mg of arginine increased antibodies titers against Newcastle disease virus. Blood and intestinal malonaldehyde levels were reduced when 200 mg of the phytogenic additive was added. Dietary supplementation of 968 mg of arginine or 100 mg of a phytogenic additive (40% Baccharis dracunculifolia, 20% Astragalus membranaceus, 20% cinnamon, and 20% grape seed extracts per kilogram of diet improves the feed conversion ratio and associated inclusion of 1144 mg of

  3. Soil CO2 evolution: Response from arginine additions

    Science.gov (United States)

    Short-term response of soil C mineralization following drying/rewetting has been proposed as an indicator of soil microbial activity. Houston Black clay was amended with four rates of arginine to vary microbial response and keep other soil properties constant. The evolution of CO2 during one and thr...

  4. Inhibition of Clostridium difficile toxin A and B by 1,2-cyclohexanedione modification of an arginine residue.

    Science.gov (United States)

    Balfanz, J; Rautenberg, P

    1989-12-29

    Toxin A (enterotoxin) and toxin B (cytotoxin) of Clostridium difficile were both inactivated by the arginine specific reagent 1,2-cyclohexanedione. Molecular stability during the inactivation process was demonstrated by SDS-PAGE analysis showing the same migration rates for modified and unmodified forms of the 230 kDa toxin A and of the 250 kDa toxin B. Cytotoxicity of both toxins as well as mouse lethality of the enterotoxin were drastically decreased as a result of the arginine modification. The reaction followed pseudo-first-order kinetics. Analysis of the data suggested that modification of a single arginine residue was sufficient to abolish the activity of both toxins.

  5. Preparation of Simvastatin Hydrogel through Arginine Addition for Drug Delivery System

    Directory of Open Access Journals (Sweden)

    Rosyida Niswati Fathmah

    2018-01-01

    Full Text Available Simvastatin is a lipid lowering agent which has been used recently as drug delivery system for stimulating bone regeneration. Because of low therapeutic efficacy and bioavailability, it is necessary to deliver simvastatin by local administration e.g. by hydrogel system. However, simvastatin has very poor solubility which restricts to prepare hydrogel formulation. The aim of this study is to improve solubility of simvastatin with arginine as co-solvent for developing a controlled released drug delivery system by loading simvastatin into gelatin hydrogel. The solubility study was performed by addition of an excess mass of simvastatin into the specified molar solutions of the arginine. All conical flasks were placed in a mechanical water bath shaker at the temperature of 25, 40, and 50 °C and shaken for a maximum period of 72 hours. The drug concentration was analyzed by UV/Visible spectroscopy at 238 nm. The hydrogel was prepared by a dehydrothermal method. The results showed that simvastatin solubility increases with increasing arginine concentrations and temperature. Characterizations showed a successful preparation of simvastatin-loaded gelatin hydrogel. The arginine simvastatin hydrogel and the gelatin hydrogel (as a blank exhibited a comparable swelling index (ca. 6.5. Furthermore, microparticles of the material show a narrow particle size distribution in the range between 150-250 μm.

  6. Unveiling the Mechanism of Arginine Transport through AdiC with Molecular Dynamics Simulations: The Guiding Role of Aromatic Residues.

    Directory of Open Access Journals (Sweden)

    Eva-Maria Krammer

    Full Text Available Commensal and pathogenic enteric bacteria have developed several systems to adapt to proton leakage into the cytoplasm resulting from extreme acidic conditions. One such system involves arginine uptake followed by export of the decarboxylated product agmatine, carried out by the arginine/agmatine antiporter (AdiC, which thus works as a virtual proton pump. Here, using classical and targeted molecular dynamics, we investigated at the atomic level the mechanism of arginine transport through AdiC of E. coli. Overall, our MD simulation data clearly demonstrate that global rearrangements of several transmembrane segments are necessary but not sufficient for achieving transitions between structural states along the arginine translocation pathway. In particular, local structural changes, namely rotameric conversions of two aromatic residues, are needed to regulate access to both the outward- and inward-facing states. Our simulations have also enabled identification of a few residues, overwhelmingly aromatic, which are essential to guiding arginine in the course of its translocation. Most of them belong to gating elements whose coordinated motions contribute to the alternating access mechanism. Their conservation in all known E. coli acid resistance antiporters suggests that the transport mechanisms of these systems share common features. Last but not least, knowledge of the functional properties of AdiC can advance our understanding of the members of the amino acid-carbocation-polyamine superfamily, notably in eukaryotic cells.

  7. Arginine and proline applied as food additives stimulate high freeze tolerance in larvae of Drosophila melanogaster.

    Science.gov (United States)

    Koštál, Vladimír; Korbelová, Jaroslava; Poupardin, Rodolphe; Moos, Martin; Šimek, Petr

    2016-08-01

    The fruit fly Drosophila melanogaster is an insect of tropical origin. Its larval stage is evolutionarily adapted for rapid growth and development under warm conditions and shows high sensitivity to cold. In this study, we further developed an optimal acclimation and freezing protocol that significantly improves larval freeze tolerance (an ability to survive at -5°C when most of the freezable fraction of water is converted to ice). Using the optimal protocol, freeze survival to adult stage increased from 0.7% to 12.6% in the larvae fed standard diet (agar, sugar, yeast, cornmeal). Next, we fed the larvae diets augmented with 31 different amino compounds, administered in different concentrations, and observed their effects on larval metabolomic composition, viability, rate of development and freeze tolerance. While some diet additives were toxic, others showed positive effects on freeze tolerance. Statistical correlation revealed tight association between high freeze tolerance and high levels of amino compounds involved in arginine and proline metabolism. Proline- and arginine-augmented diets showed the highest potential, improving freeze survival to 42.1% and 50.6%, respectively. Two plausible mechanisms by which high concentrations of proline and arginine might stimulate high freeze tolerance are discussed: (i) proline, probably in combination with trehalose, could reduce partial unfolding of proteins and prevent membrane fusions in the larvae exposed to thermal stress (prior to freezing) or during freeze dehydration; (ii) both arginine and proline are exceptional among amino compounds in their ability to form supramolecular aggregates which probably bind partially unfolded proteins and inhibit their aggregation under increasing freeze dehydration. © 2016. Published by The Company of Biologists Ltd.

  8. Partial alanine scan of mast cell degranulating peptide (MCD): importance of the histidine- and arginine residues.

    Science.gov (United States)

    Buku, Angeliki; Mendlowitz, Milton; Condie, Barry A; Price, Joseph A

    2004-06-01

    The influence of the two histidine and two arginine residues of mast cell degranulating peptide (MCD) in activity and binding was studied by replacing these amino acids in the MCD sequence with L-alanine. Their histamine releasing activity was determined on rat peritoneal mast cells. Their binding affinity to the FcepsilonRIalpha binding subunit of the human mast cell receptor protein, was carried out using fluorescence polarization. The histamine assay showed that replacement of His13 by Ala o ccurred without loss of activity compared with the activity of MCD. Alanine substitutions for Arg7 and His8 resulted in an approximately 40 fold increase, and for Arg16 in a 14-fold increase in histamine-releasing activity of MCD. The binding affinities of the analogs were tested by competitive displacement of bound fluorescent MCD peptide from the FcepsilonRIalpha binding protein of the mast cell receptor by the Ala analogs using fluorescence polarization. The analogs Ala8 (for His) and Ala16 (for Arg) showed the same binding affinities as MCD, whereas analog Ala7 (for Arg) and analog Ala13 (for His) showed slightly better binding affinity than the parent compound. This study showed that the introduction of alanine residues in these positions resulted in MCD agonists of diverse potency. These findings will be useful in further MCD structure-activity studies.

  9. Binding of the human "electron transferring flavoprotein" (ETF) to the medium chain acyl-CoA dehydrogenase (MCAD) involves an arginine and histidine residue.

    Science.gov (United States)

    Parker, Antony R

    2003-10-01

    The interaction between the "electron transferring flavoprotein" (ETF) and medium chain acyl-CoA dehydrogenase (MCAD) enables successful flavin to flavin electron transfer, crucial for the beta-oxidation of fatty acids. The exact biochemical determinants for ETF binding to MCAD are unknown. Here we show that binding of human ETF, to MCAD, was inhibited by 2,3-butanedione and diethylpyrocarbonate (DEPC) and reversed by incubation with free arginine and hydroxylamine respectively. Spectral analyses of native ETF vs modified ETF suggested that flavin binding was not affected and that the loss of ETF activity with MCAD involved modification of one ETF arginine residue and one ETF histidine residue respectively. MCAD and octanoyl-CoA protected ETF against inactivation by both 2,3-butanedione and DEPC indicating that the arginine and histidine residues are present in or around the MCAD binding site. Comparison of exposed arginine and histidine residues among different ETF species, however, indicates that arginine residues are highly conserved but that histidine residues are not. These results lead us to conclude that this single arginine residue is essential for the binding of ETF to MCAD, but that the single histidine residue, although involved, is not.

  10. Multiple Arginine Residues Are Methylated in Drosophila Mre11 and Required for Survival Following Ionizing Radiation.

    Science.gov (United States)

    Yuan, Qing; Tian, Ran; Zhao, Haiying; Li, Lijuan; Bi, Xiaolin

    2018-05-31

    Mre11 is a key player for DNA double strand break repair. Previous studies have shown that mammalian Mre11 is methylated at multiple arginines in its C-terminal Glycine-Arginine-Rich motif (GAR) by protein arginine methyltransferase PRMT1. Here, we found that the Drosophila Mre11 is methylated at arginines 559, 563, 565, and 569 in the GAR motif by DART1, the Drosophila homolog of PRMT1. Mre11 interacts with DART1 in S2 cells, and this interaction does not require the GAR motif. Arginines methylated Mre11 localizes exclusively in the nucleus as soluble nuclear protein or chromatin-binding protein. To study the in vivo functions of methylation, we generated the single Arg-Ala and all Arginines mutated flies. We found these mutants were sensitive to ionizing radiation. Furthermore, Arg-Ala mutated flies had no irradiation induced G2/M checkpoint defect in wing disc and eye disc. Thus, we provided evidence that arginines in Drosophila Mre11 are methylated by DART1 methytransferase and flies loss of arginine methylation are sensitive to irradiation. Copyright © 2018 Yuan et al.

  11. Chemical mechanisms of histone lysine and arginine modifications

    OpenAIRE

    Smith, Brian C.; Denu, John M.

    2008-01-01

    Histone lysine and arginine residues are subject to a wide array of post-translational modifications including methylation, citrullination, acetylation, ubiquitination, and sumoylation. The combinatorial action of these modifications regulates critical DNA processes including replication, repair, and transcription. In addition, enzymes that modify histone lysine and arginine residues have been correlated with a variety of human diseases including arthritis, cancer, heart disease, diabetes, an...

  12. The DEAD-Box Protein CYT-19 Uses Arginine Residues in Its C-Tail To Tether RNA Substrates.

    Science.gov (United States)

    Busa, Veronica F; Rector, Maxwell J; Russell, Rick

    2017-07-18

    DEAD-box proteins are nonprocessive RNA helicases that play diverse roles in cellular processes. The Neurospora crassa DEAD-box protein CYT-19 promotes mitochondrial group I intron splicing and functions as a general RNA chaperone. CYT-19 includes a disordered, arginine-rich "C-tail" that binds RNA, positioning the helicase core to capture and unwind nearby RNA helices. Here we probed the C-tail further by varying the number and positions of arginines within it. We found that removing sets of as few as four of the 11 arginines reduced RNA unwinding activity (k cat /K M ) to a degree equivalent to that seen upon removal of the C-tail, suggesting that a minimum or "threshold" number of arginines is required. In addition, a mutant with 16 arginines displayed RNA unwinding activity greater than that of wild-type CYT-19. The C-tail modifications impacted unwinding only of RNA helices within constructs that included an adjacent helix or structured RNA element that would allow C-tail binding, indicating that the helicase core remained active in the mutants. In addition, changes in RNA unwinding efficiency of the mutants were mirrored by changes in functional RNA affinity, as determined from the RNA concentration dependence of ATPase activity, suggesting that the C-tail functions primarily to increase RNA affinity. Interestingly, the salt concentration dependence of RNA unwinding activity is unaffected by C-tail composition, suggesting that the C-tail uses primarily hydrogen bonding, not electrostatic interactions, to bind double-stranded RNA. Our results provide insights into how an unstructured C-tail contributes to DEAD-box protein activity and suggest parallels with other families of RNA- and DNA-binding proteins.

  13. Characterization of conserved arginine residues on Cdt1 that affect licensing activity and interaction with Geminin or Mcm complex.

    Science.gov (United States)

    You, Zhiying; Ode, Koji L; Shindo, Mayumi; Takisawa, Haruhiko; Masai, Hisao

    2016-05-02

    All organisms ensure once and only once replication during S phase through a process called replication licensing. Cdt1 is a key component and crucial loading factor of Mcm complex, which is a central component for the eukaryotic replicative helicase. In higher eukaryotes, timely inhibition of Cdt1 by Geminin is essential to prevent rereplication. Here, we address the mechanism of DNA licensing using purified Cdt1, Mcm and Geminin proteins in combination with replication in Xenopus egg extracts. We mutagenized the 223th arginine of mouse Cdt1 (mCdt1) to cysteine or serine (R-S or R-C, respectively) and 342nd and 346th arginines constituting an arginine finger-like structure to alanine (RR-AA). The RR-AA mutant of Cdt1 could not only rescue the DNA replication activity in Cdt1-depleted extracts but also its specific activity for DNA replication and licensing was significantly increased compared to the wild-type protein. In contrast, the R223 mutants were partially defective in rescue of DNA replication and licensing. Biochemical analyses of these mutant Cdt1 proteins indicated that the RR-AA mutation disabled its functional interaction with Geminin, while R223 mutations resulted in ablation in interaction with the Mcm2∼7 complex. Intriguingly, the R223 mutants are more susceptible to the phosphorylation-induced inactivation or chromatin dissociation. Our results show that conserved arginine residues play critical roles in interaction with Geminin and Mcm that are crucial for proper conformation of the complexes and its licensing activity.

  14. Nicotinic Receptor Transduction Zone: Invariant Arginine Couples to Multiple Electron-Rich Residues

    Science.gov (United States)

    Mukhtasimova, Nuriya; Sine, Steven M.

    2013-01-01

    Summary Gating of the muscle-type acetylcholine receptor (AChR) channel depends on communication between the ACh-binding site and the remote ion channel. A key region for this communication is located within the structural transition zone between the ligand-binding and pore domains. Here, stemming from β-strand 10 of the binding domain, the invariant αArg209 lodges within the hydrophobic interior of the subunit and is essential for rapid and efficient channel gating. Previous charge-reversal experiments showed that the contribution of αArg209 to channel gating depends strongly on αGlu45, also within this region. Here we determine whether the contribution of αArg209 to channel gating depends on additional anionic or electron-rich residues in this region. Also, to reconcile diverging findings in the literature, we compare the dependence of αArg209 on αGlu45 in AChRs from different species, and compare the full agonist ACh with the weak agonist choline. Our findings reveal that the contribution of αArg209 to channel gating depends on additional nearby electron-rich residues, consistent with both electrostatic and steric contributions. Furthermore, αArg209 and αGlu45 show a strong interdependence in both human and mouse AChRs, whereas the functional consequences of the mutation αE45R depend on the agonist. The emerging picture shows a multifaceted network of interdependent residues that are required for communication between the ligand-binding and pore domains. PMID:23442857

  15. Nicotinic receptor transduction zone: invariant arginine couples to multiple electron-rich residues.

    Science.gov (United States)

    Mukhtasimova, Nuriya; Sine, Steven M

    2013-01-22

    Gating of the muscle-type acetylcholine receptor (AChR) channel depends on communication between the ACh-binding site and the remote ion channel. A key region for this communication is located within the structural transition zone between the ligand-binding and pore domains. Here, stemming from β-strand 10 of the binding domain, the invariant αArg209 lodges within the hydrophobic interior of the subunit and is essential for rapid and efficient channel gating. Previous charge-reversal experiments showed that the contribution of αArg209 to channel gating depends strongly on αGlu45, also within this region. Here we determine whether the contribution of αArg209 to channel gating depends on additional anionic or electron-rich residues in this region. Also, to reconcile diverging findings in the literature, we compare the dependence of αArg209 on αGlu45 in AChRs from different species, and compare the full agonist ACh with the weak agonist choline. Our findings reveal that the contribution of αArg209 to channel gating depends on additional nearby electron-rich residues, consistent with both electrostatic and steric contributions. Furthermore, αArg209 and αGlu45 show a strong interdependence in both human and mouse AChRs, whereas the functional consequences of the mutation αE45R depend on the agonist. The emerging picture shows a multifaceted network of interdependent residues that are required for communication between the ligand-binding and pore domains. Copyright © 2013 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  16. Facts about food irradiation: Irradiation and food additives and residues

    International Nuclear Information System (INIS)

    1991-01-01

    This fact sheet considers the issue of the irradiation of food containing food additives or pesticide residues. The conclusion is that there is no health hazard posed by radiolytic products of pesticides or food additives. 1 ref

  17. A single arginine residue is required for the interaction of the electron transferring flavoprotein (ETF) with three of its dehydrogenase partners.

    Science.gov (United States)

    Parker, Antony R

    2003-12-01

    The interaction of several dehydrogenases with the electron transferring flavoprotein (ETF) is a crucial step required for the successful transfer of electrons into the electron transport chain. The exact determinants regarding the interaction of ETF with its dehydrogenase partners are still unknown. Chemical modification of ETF with arginine-specific reagents resulted in the loss, to varying degrees, of activity with medium chain acyl-coenzyme A dehydrogenase (MCAD). The kinetic profiles showed the inactivations followed pseudo-first-order kinetics for all reagents used. For activity with MCAD, maximum inactivation of ETF was accomplished by 2,3-butanedione (4% residual activity after 120 min) and it was shown that modification of one arginine residue was responsible for the inactivation. Almost 100% restoration of this ETF activity was achieved upon incubation with free arginine. However, the same 2,3-butanedione modified ETF only possessed decreased activity with dimethylglycine-(DMGDH, 44%) and sarcosine- (SDH, 27%) dehydrogenases unlike the abolition with MCAD. Full protection of ETF from arginine modification by 2,3-butanedione was achieved using substrate-protected DMGDH, MCAD and SDH respectively. Cross-protection studies of ETF with the three dehydrogenases implied use of the same single arginine residue in the binding of all three dehydrogenases. These results lead us to conclude that this single arginine residue is essential in the binding of the ETF to MCAD, but only contributes partially to the binding of ETF to SDH and DMGDH and thus, the determinants of the dehydrogenase binding sites overlap but are not identical.

  18. An Additive-Multiplicative Restricted Mean Residual Life Model

    DEFF Research Database (Denmark)

    Mansourvar, Zahra; Martinussen, Torben; Scheike, Thomas H.

    2016-01-01

    mean residual life model to study the association between the restricted mean residual life function and potential regression covariates in the presence of right censoring. This model extends the proportional mean residual life model using an additive model as its covariate dependent baseline....... For the suggested model, some covariate effects are allowed to be time-varying. To estimate the model parameters, martingale estimating equations are developed, and the large sample properties of the resulting estimators are established. In addition, to assess the adequacy of the model, we investigate a goodness...

  19. Characterization of an endoprotease from rat small intestinal mucosal secretory granules which generates somatostatin-28 from prosomatostatin by cleavage after a single arginine residue

    NARCIS (Netherlands)

    Beinfeld, M. C.; Bourdais, J.; Kuks, P.; Morel, A.; Cohen, P.

    1989-01-01

    We have extracted, characterized, and partially purified an enzyme from secretory granules from rat small intestinal mucosa which cleaves a synthetic prosomatostatin substrate on the carboxyl side of a single arginine residue. This substrate Leu-Gln-Arg-Ser-Ala-Asn-Ser-NH2 contains the monobasic

  20. Arginine-aromatic interactions and their effects on arginine-induced solubilization of aromatic solutes and suppression of protein aggregation

    KAUST Repository

    Shah, Dhawal

    2011-09-21

    We examine the interaction of aromatic residues of proteins with arginine, an additive commonly used to suppress protein aggregation, using experiments and molecular dynamics simulations. An aromatic-rich peptide, FFYTP (a segment of insulin), and lysozyme and insulin are used as model systems. Mass spectrometry shows that arginine increases the solubility of FFYTP by binding to the peptide, with the simulations revealing the predominant association of arginine to be with the aromatic residues. The calculations further show a positive preferential interaction coefficient, Γ XP, contrary to conventional thinking that positive Γ XP\\'s indicate aggregation rather than suppression of aggregation. Simulations with lysozyme and insulin also show arginine\\'s preference for aromatic residues, in addition to acidic residues. We use these observations and earlier results reported by us and others to discuss the possible implications of arginine\\'s interactions with aromatic residues on the solubilization of aromatic moieties and proteins. Our results also highlight the fact that explanations based purely on Γ XP, which measures average affinity of an additive to a protein, could obscure or misinterpret the underlying molecular mechanisms behind additive-induced suppression of protein aggregation. © 2011 American Institute of Chemical Engineers (AIChE).

  1. Effect of repeated pesticide applications on soil properties in cotton fields: II. Insecticide residues and impact on dehydrogenase and arginine deaminase activities

    International Nuclear Information System (INIS)

    Vig, K.; Singh, D.K.; Agarwal, H.C.; Dhawan, A.K.; Dureja, P.

    2001-01-01

    Insecticides were applied sequentially at recommended dosages post crop emergence in cotton fields and soil was sampled at regular intervals after each treatment. Soil was analysed for insecticide residues and activity of the enzymes dehydrogenase and arginine deaminase. Insecticide residues detected in the soil were in small quantities and they did not persist for long. Only endosulfan leached below 15 cm. Insecticides had only temporary effects on enzyme activities which disappeared either before the next insecticide treatment or by the end of the experimental period. (author)

  2. Spectral Envelopes and Additive + Residual Analysis/Synthesis

    Science.gov (United States)

    Rodet, Xavier; Schwarz, Diemo

    The subject of this chapter is the estimation, representation, modification, and use of spectral envelopes in the context of sinusoidal-additive-plus-residual analysis/synthesis. A spectral envelope is an amplitude-vs-frequency function, which may be obtained from the envelope of a short-time spectrum (Rodet et al., 1987; Schwarz, 1998). [Precise definitions of such an envelope and short-time spectrum (STS) are given in Section 2.] The additive-plus-residual analysis/synthesis method is based on a representation of signals in terms of a sum of time-varying sinusoids and of a non-sinusoidal residual signal [e.g., see Serra (1989), Laroche et al. (1993), McAulay and Quatieri (1995), and Ding and Qian (1997)]. Many musical sound signals may be described as a combination of a nearly periodic waveform and colored noise. The nearly periodic part of the signal can be viewed as a sum of sinusoidal components, called partials, with time-varying frequency and amplitude. Such sinusoidal components are easily observed on a spectral analysis display (Fig. 5.1) as obtained, for instance, from a discrete Fourier transform.

  3. In vitro mutagenesis studies at the arginine residues of adenylate kinase. A revised binding site for AMP in the X-ray-deduced model

    International Nuclear Information System (INIS)

    Kim, Hyo Joon; Nishikawa, Satoshi; Tokutomi, Yuiko; Uesugi, Seiichi; Takenaka, Hitoshi; Hamada, Minoru; Kuby, S.A.

    1990-01-01

    Although X-ray crystallographic and NMR studies have been made on the adenylate kinases, the substrate-binding sites are not unequivocally established. In an attempt to shed light on the binding sites for MgATP 2- and for AMP 2- in human cytosolic adenylate kinase, the authors have investigated the enzymic effects of replacement of the arginine residues, which had been assumed by Pai et al. to interact with the phosphoryl groups of AMP 2- and MgATP 2- . With use of the site-directed mutagenesis method, point mutations were made in the artificial gene for hAK1 to replace these arginine residues with alanyl residues and yield the mutants R44A hAK1, R132A hAK1, R138A hAK1, and R149A hAK1. The resulting large increases in the K m,app values for AMP 2- of the mutant enzymes, the relatively small increases in the K m,app values for MgATP 2- , and the fact that the R132A, R138A, and R149A mutant enzymes proved to be very poor catalysts are consistent with the idea that the assigned substrate binding sites of Pai et al. have been reversed and that their ATP-binding site may be assigned as the AMP site

  4. Arginine-aromatic interactions and their effects on arginine-induced solubilization of aromatic solutes and suppression of protein aggregation

    KAUST Repository

    Shah, Dhawal; Li, Jianguo; Shaikh, Abdul Rajjak; Rajagopalan, Raj

    2011-01-01

    We examine the interaction of aromatic residues of proteins with arginine, an additive commonly used to suppress protein aggregation, using experiments and molecular dynamics simulations. An aromatic-rich peptide, FFYTP (a segment of insulin), and lysozyme and insulin are used as model systems. Mass spectrometry shows that arginine increases the solubility of FFYTP by binding to the peptide, with the simulations revealing the predominant association of arginine to be with the aromatic residues. The calculations further show a positive preferential interaction coefficient, Γ XP, contrary to conventional thinking that positive Γ XP's indicate aggregation rather than suppression of aggregation. Simulations with lysozyme and insulin also show arginine's preference for aromatic residues, in addition to acidic residues. We use these observations and earlier results reported by us and others to discuss the possible implications of arginine's interactions with aromatic residues on the solubilization of aromatic moieties and proteins. Our results also highlight the fact that explanations based purely on Γ XP, which measures average affinity of an additive to a protein, could obscure or misinterpret the underlying molecular mechanisms behind additive-induced suppression of protein aggregation. © 2011 American Institute of Chemical Engineers (AIChE).

  5. The Ergogenic Potential of Arginine

    Directory of Open Access Journals (Sweden)

    La Bounty Paul M

    2004-12-01

    Full Text Available Abstract Arginine is a conditionally essential amino acid that is involved in protein synthesis, the detoxification of ammonia, and its conversion to glucose as well as being catabolized to produce energy. In addition to these physiological functions, arginine has been purported to have ergogenic potential. Athletes have taken arginine for three main reasons: 1 its role in the secretion of endogenous growth hormone; 2 its involvement in the synthesis of creatine; 3 its role in augmenting nitric oxide. These aspects of arginine supplementation will be discussed as well as a review of clinical investigations involving exercise performance and arginine ingestion.

  6. The arginine residue within the C-terminal active core of Bombyx mori pheromone biosynthesis-activating neuropeptide (PBAN is essential for receptor binding and activation

    Directory of Open Access Journals (Sweden)

    Takeshi eKawai

    2012-03-01

    Full Text Available In most lepidopteran insects, the biosynthesis of sex pheromones is regulated by pheromone biosynthesis activating neuropeptide (PBAN. Bombyx mori PBAN (BomPBAN consists of 33 amino acid residues and contains a C-terminus FSPRLamide motif as the active core. Among neuropeptides containing the FXPRLamide motif, the arginine (Arg, R residue two positions from the C-terminus is highly conserved across several neuropeptides, which can be designated as RXamide peptides. The purpose of this study was to reveal the role of the Arg residue in the BomPBAN active core. We synthesized a ten-residue peptide corresponding to the C-terminal part of BomPBAN with a series of point mutants at the 2nd position (ie, Arg from the C-terminus, termed the C2 position, and measured their efficacy in stimulating Ca2+ influx in insect cells concomitantly expressing a fluorescent PBAN receptor chimera (PBANR-EGFP and loaded with the fluorescent Ca2+ indicator, Fura Red-AM. PBAN analogs with the C2 position replaced with alanine (Ala, A, aspartic acid (Asp, D, serine (Ser, S or L-2-aminooctanoic acid (Aoc decreased PBAN-like activity. RC2A (SKTRYFSPALamide and RC2D (SKTRYFSPDLamide had the lowest activity and could not inhibit the activity of PBAN C10 (SKTRYFSPRLamide. We also prepared Rhodamine Red-labeled PBAN analogs of the mutants and examined their ability to bind PBANR. In contrast to 100 nM Rhodamine Red-PBAN C10, none of the mutants at the same concentration exhibited PBANR binding. Taken together, our results demonstrate that the C2 Arg residue in BomPBAN is essential for PBANR binding and activation.

  7. Powder addition assessment of manganese residue ceramic matrix coating

    International Nuclear Information System (INIS)

    Conceicao, A.C.R. da; Santos, O.C.; Leao, M.A.

    2016-01-01

    The use of recycled materials in the composition of new products follows the production's worldwide trending, meeting new technological requirements and environmental concerns. This work aims to utilize the residue of manganese dust on ceramic mass for the production of ceramic coating. The raw materials were characterized by both x-ray fluorescence and diffraction. The powder residue added to clay in the percentage of 0%, 5%, 10% and 15% (measured in weight) was compressed by a uniaxial pressing of 30MPa and the sintering temperatures were 900°, 1000° and 1100°. The samples were analysed in relation to flexural strength, bulk density, water absorption and linear shrinkage. The microstructural variation was also analysed by x-ray diffraction and electron microscopy. The results showed that there is a viability for the production of porcelain ceramic coating (A3 and A4 formulations) and stoneware (A2 formulation) according to the specification of technical standards. author)

  8. Protein arginine methyltransferase 1 regulates herpes simplex virus replication through ICP27 RGG-box methylation

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Jungeun; Shin, Bongjin; Park, Eui-Soon; Yang, Sujeong; Choi, Seunga [Department of Microbiology, Chungnam National University, 220 Gung-dong, Yuseong-gu, Daejon 305-764 (Korea, Republic of); BK21 Bio Brain Center, Chungnam National University, 220 Gung-dong, Yuseong-gu, Daejon 305-764 (Korea, Republic of); Kang, Misun [Department of Microbiology, Chungnam National University, 220 Gung-dong, Yuseong-gu, Daejon 305-764 (Korea, Republic of); Rho, Jaerang, E-mail: jrrho@cnu.ac.kr [Department of Microbiology, Chungnam National University, 220 Gung-dong, Yuseong-gu, Daejon 305-764 (Korea, Republic of); BK21 Bio Brain Center, Chungnam National University, 220 Gung-dong, Yuseong-gu, Daejon 305-764 (Korea, Republic of); GRAST, Chungnam National University, 220 Gung-dong, Yuseong-gu, Daejon 305-764 (Korea, Republic of)

    2010-01-01

    Protein arginine methylation is involved in viral infection and replication through the modulation of diverse cellular processes including RNA metabolism, cytokine signaling, and subcellular localization. It has been suggested previously that the protein arginine methylation of the RGG-box of ICP27 is required for herpes simplex virus type-1 (HSV-1) viral replication and gene expression in vivo. However, a cellular mediator for this process has not yet been identified. In our current study, we show that the protein arginine methyltransferase 1 (PRMT1) is a cellular mediator of the arginine methylation of ICP27 RGG-box. We generated arginine substitution mutants in this domain and examined which arginine residues are required for methylation by PRMT1. R138, R148 and R150 were found to be the major sites of this methylation but additional arginine residues serving as minor methylation sites are still required to sustain the fully methylated form of ICP27 RGG. We also demonstrate that the nuclear foci-like structure formation, SRPK interactions, and RNA-binding activity of ICP27 are modulated by the arginine methylation of the ICP27 RGG-box. Furthermore, HSV-1 replication is inhibited by hypomethylation of this domain resulting from the use of general PRMT inhibitors or arginine mutations. Our data thus suggest that the PRMT1 plays a key role as a cellular regulator of HSV-1 replication through ICP27 RGG-box methylation.

  9. Mechanistic Basis for Type 2 Long QT Syndrome Caused by KCNH2 Mutations that Disrupt Conserved Arginine Residue in the Voltage Sensor

    Science.gov (United States)

    McBride, Christie M.; Smith, Ashley M.; Smith, Jennifer L.; Reloj, Allison R.; Velasco, Ellyn J.; Powell, Jonathan; Elayi, Claude S.; Bartos, Daniel C.; Burgess, Don E.

    2013-01-01

    KCNH2 encodes the Kv11.1 channel, which conducts the rapidly activating delayed rectifier K+ current (IKr) in the heart. KCNH2 mutations cause type 2 long QT syndrome (LQT2), which increases the risk for life-threatening ventricular arrhythmias. LQT2 mutations are predicted to prolong the cardiac action potential (AP) by reducing IKr during repolarization. Kv11.1 contains several conserved basic amino acids in the fourth transmembrane segment (S4) of the voltage sensor that are important for normal channel trafficking and gating. This study sought to determine the mechanism(s) by which LQT2 mutations at conserved arginine residues in S4 (R531Q, R531W or R534L) alter Kv11.1 function. Western blot analyses of HEK293 cells transiently expressing R531Q, R531W or R534L suggested that only R534L inhibited Kv11.1 trafficking. Voltage-clamping experiments showed that R531Q or R531W dramatically altered Kv11.1 current (IKv11.1) activation, inactivation, recovery from inactivation and deactivation. Coexpression of wild type (to mimic the patients’ genotypes) mostly corrected the changes in IKv11.1 activation and inactivation, but deactivation kinetics were still faster. Computational simulations using a human ventricular AP model showed that accelerating deactivation rates was sufficient to prolong the AP, but these effects were minimal compared to simply reducing IKr. These are the first data to demonstrate that coexpressing wild type can correct activation and inactivation dysfunction caused by mutations at a critical voltage-sensing residue in Kv11.1. We conclude that some Kv11.1 mutations might accelerate deactivation to cause LQT2 but that the ventricular AP duration is much more sensitive to mutations that decrease IKr. This likely explains why most LQT2 mutations are nonsense or trafficking-deficient. PMID:23546015

  10. Mechanistic basis for type 2 long QT syndrome caused by KCNH2 mutations that disrupt conserved arginine residues in the voltage sensor.

    Science.gov (United States)

    McBride, Christie M; Smith, Ashley M; Smith, Jennifer L; Reloj, Allison R; Velasco, Ellyn J; Powell, Jonathan; Elayi, Claude S; Bartos, Daniel C; Burgess, Don E; Delisle, Brian P

    2013-05-01

    KCNH2 encodes the Kv11.1 channel, which conducts the rapidly activating delayed rectifier K+ current (I Kr) in the heart. KCNH2 mutations cause type 2 long QT syndrome (LQT2), which increases the risk for life-threatening ventricular arrhythmias. LQT2 mutations are predicted to prolong the cardiac action potential (AP) by reducing I Kr during repolarization. Kv11.1 contains several conserved basic amino acids in the fourth transmembrane segment (S4) of the voltage sensor that are important for normal channel trafficking and gating. This study sought to determine the mechanism(s) by which LQT2 mutations at conserved arginine residues in S4 (R531Q, R531W or R534L) alter Kv11.1 function. Western blot analyses of HEK293 cells transiently expressing R531Q, R531W or R534L suggested that only R534L inhibited Kv11.1 trafficking. Voltage-clamping experiments showed that R531Q or R531W dramatically altered Kv11.1 current (I Kv11.1) activation, inactivation, recovery from inactivation and deactivation. Coexpression of wild type (to mimic the patients' genotypes) mostly corrected the changes in I Kv11.1 activation and inactivation, but deactivation kinetics were still faster. Computational simulations using a human ventricular AP model showed that accelerating deactivation rates was sufficient to prolong the AP, but these effects were minimal compared to simply reducing I Kr. These are the first data to demonstrate that coexpressing wild type can correct activation and inactivation dysfunction caused by mutations at a critical voltage-sensing residue in Kv11.1. We conclude that some Kv11.1 mutations might accelerate deactivation to cause LQT2 but that the ventricular AP duration is much more sensitive to mutations that decrease I Kr. This likely explains why most LQT2 mutations are nonsense or trafficking-deficient.

  11. Influence of organic waste and residue mud additions on chemical, physical and microbial properties of bauxite residue sand.

    Science.gov (United States)

    Jones, Benjamin E H; Haynes, Richard J; Phillips, Ian R

    2011-02-01

    In an alumina refinery, bauxite ore is treated with sodium hydroxide at high temperatures and pressures and for every tone of alumina produced, about 2 tones of alkaline, saline bauxite processing waste is also produced. At Alcoa, a dry stacking system of disposal is used, and it is the sand fraction of the processing waste that is rehabilitated. There is little information available regarding the most appropriate amendments to add to the processing sand to aid in revegetation. The purpose of this study was to investigate how the addition of organic wastes (biosolids and poultry manure), in the presence or absence of added residue mud, would affect the properties of the residue sand and its suitability for revegetation. Samples of freshly deposited residue sand were collected from Alcoa's Kwinana refinery. Samples were treated with phosphogypsum (2% v/v), incubated, and leached. A laboratory experiment was then set up in which the two organic wastes were applied at 0 or the equivalent to 60 tones ha(-1) in combination with residue mud added at rates of 0%, 10% and 20% v/v. Samples were incubated for 8 weeks, after which, key chemical, physical and microbial properties of the residue sand were measured along with seed germination. Additions of residue mud increased exchangeable Na(+), ESP and the pH, and HCO (3) (-) and Na(+) concentrations in saturation paste extracts. Additions of biosolids and poultry manure increased concentrations of extractable P, NH (4) (+) , K, Mg, Cu, Zn, Mn and Fe. Addition of residue mud, in combination with organic wastes, caused a marked decrease in macroporosity and a concomitant increase in mesoporosity, available water holding capacity and the quantity of water held at field capacity. With increasing residue mud additions, the percentage of sample present as sand particles (2 mm diameter) increased; greatest aggregation occurred where a combination of residue mud and poultry manure were added. Stability of aggregates, as measured by

  12. Two Arginine Residues of Streptococcus gordonii Sialic Acid-Binding Adhesin Hsa Are Essential for Interaction to Host Cell Receptors.

    Directory of Open Access Journals (Sweden)

    Yumiko Urano-Tashiro

    Full Text Available Hsa is a large, serine-rich protein of Streptococcus gordonii DL1 that mediates binding to α2-3-linked sialic acid termini of glycoproteins, including platelet glycoprotein Ibα, and erythrocyte membrane protein glycophorin A, and band 3. The binding of Hsa to platelet glycoprotein Ibα contributes to the pathogenesis of infective endocarditis. This interaction appears to be mediated by a second non-repetitive region (NR2 of Hsa. However, the molecular details of the interaction between the Hsa NR2 region and these glycoproteins are not well understood. In the present study, we identified the amino acid residues of the Hsa NR2 region that are involved in sialic acid recognition. To identify the sialic acid-binding site of Hsa NR2 region, we prepared various mutants of Hsa NR2 fused with glutathione transferase. Fusion proteins harboring Arg340 to Asn (R340N or Arg365 to Asn (R365N substitutions in the NR2 domain exhibited significantly reduced binding to human erythrocytes and platelets. A sugar-binding assay showed that these mutant proteins abolished binding to α2-3-linked sialic acid. Furthermore, we established S. gordonii DL1 derivatives that encoded the corresponding Hsa mutant protein. In whole-cell assays, these mutant strains showed significant reductions in hemagglutination, in platelet aggregation, and in adhesion to human leukocytes. These results indicate that the Arg340 and Arg365 residues of Hsa play an important role in the binding of Hsa to α2-3-linked sialic acid-containing glycoproteins.

  13. Addition of arginine and leucine to low or normal protein diets: performance, carcass characteristics and intramuscular fat of finishing pigs

    Directory of Open Access Journals (Sweden)

    Núria Tous

    2016-12-01

    Full Text Available The effect of dietary crude protein (CP reduction, supplementation with arginine or leucine on intramuscular fat (IMF content was evaluated in (Landrace × Duroc × Pietrain pigs. One-hundred and eight barrows (67 ± 4 kg were assigned to six diets (n=6 pens of 3 pigs each: four normal CP diets containing 16% CP from 60 to 90 kg and 13% CP from 90 to 115 kg live weight (normal protein; normal protein high Arg, normal protein high Leu or normal protein high Arg and Leu and two low CP diets containing 14% CP from 60 to 90 kg and 11.8% CP from 90 to 115 kg live weight (with or without supplementation of both amino acids. The high Leu and Arg diets were supplemented to obtain ratios of standard ileal digestible Leu/Lys and Arg/Lys of 4 and 2, respectively. While feed to gain ratio tended to increase (p<0.05, final weight (p<0.01, average daily feed intake (ADFI (p<0.05 and average daily gain (ADG (p<0.01 were reduced in animals fed low-protein diets supplemented with Arg and Leu compared to the ones fed low-protein diet unsupplemented. Marbling and IMF content in loin were reduced when Arg was supplemented (p<0.05 in normal protein diets. Supplementing these diets with Arg also reduced belly weight (p<0.01 and increased lean meat percentage (p<0.05. Contrary to the initial hypothesis, reduction of CP or dietary supplementation with Leu had no effect on IMF content and supplementation with Arg reduced it.

  14. Addition of arginine and leucine to low or normal protein diets: performance, carcass characteristics and intramuscular fat of finishing pigs

    Energy Technology Data Exchange (ETDEWEB)

    Tous, N.; Lizardo, R.; Vilà, B.; Gispert, M.; Font-i-Furnols, M.; Esteve-Garcia, E.

    2016-07-01

    The effect of dietary crude protein (CP) reduction, supplementation with arginine or leucine on intramuscular fat (IMF) content was evaluated in (Landrace × Duroc) × Pietrain pigs. One-hundred and eight barrows (67 ± 4 kg) were assigned to six diets (n=6 pens of 3 pigs each): four normal CP diets containing 16% CP from 60 to 90 kg and 13% CP from 90 to 115 kg live weight (normal protein; normal protein high Arg, normal protein high Leu or normal protein high Arg and Leu) and two low CP diets containing 14% CP from 60 to 90 kg and 11.8% CP from 90 to 115 kg live weight (with or without supplementation of both amino acids). The high Leu and Arg diets were supplemented to obtain ratios of standard ileal digestible Leu/Lys and Arg/Lys of 4 and 2, respectively. While feed to gain ratio tended to increase (p<0.05), final weight (p<0.01), average daily feed intake (ADFI) (p<0.05) and average daily gain (ADG) (p<0.01) were reduced in animals fed low-protein diets supplemented with Arg and Leu compared to the ones fed low-protein diet unsupplemented. Marbling and IMF content in loin were reduced when Arg was supplemented (p<0.05) in normal protein diets. Supplementing these diets with Arg also reduced belly weight (p<0.01) and increased lean meat percentage (p<0.05). Contrary to the initial hypothesis, reduction of CP or dietary supplementation with Leu had no effect on IMF content and supplementation with Arg reduced it.

  15. Addition of arginine and leucine to low or normal protein diets: performance, carcass characteristics and intramuscular fat of finishing pigs

    International Nuclear Information System (INIS)

    Tous, N.; Lizardo, R.; Vilà, B.; Gispert, M.; Font-i-Furnols, M.; Esteve-Garcia, E.

    2016-01-01

    The effect of dietary crude protein (CP) reduction, supplementation with arginine or leucine on intramuscular fat (IMF) content was evaluated in (Landrace × Duroc) × Pietrain pigs. One-hundred and eight barrows (67 ± 4 kg) were assigned to six diets (n=6 pens of 3 pigs each): four normal CP diets containing 16% CP from 60 to 90 kg and 13% CP from 90 to 115 kg live weight (normal protein; normal protein high Arg, normal protein high Leu or normal protein high Arg and Leu) and two low CP diets containing 14% CP from 60 to 90 kg and 11.8% CP from 90 to 115 kg live weight (with or without supplementation of both amino acids). The high Leu and Arg diets were supplemented to obtain ratios of standard ileal digestible Leu/Lys and Arg/Lys of 4 and 2, respectively. While feed to gain ratio tended to increase (p<0.05), final weight (p<0.01), average daily feed intake (ADFI) (p<0.05) and average daily gain (ADG) (p<0.01) were reduced in animals fed low-protein diets supplemented with Arg and Leu compared to the ones fed low-protein diet unsupplemented. Marbling and IMF content in loin were reduced when Arg was supplemented (p<0.05) in normal protein diets. Supplementing these diets with Arg also reduced belly weight (p<0.01) and increased lean meat percentage (p<0.05). Contrary to the initial hypothesis, reduction of CP or dietary supplementation with Leu had no effect on IMF content and supplementation with Arg reduced it.

  16. Numerical simulation of residual stress in laser based additive manufacturing process

    Science.gov (United States)

    Kalyan Panda, Bibhu; Sahoo, Seshadev

    2018-03-01

    Minimizing the residual stress build-up in metal-based additive manufacturing plays a pivotal role in selecting a particular material and technique for making an industrial part. In beam-based additive manufacturing, although a great deal of effort has been made to minimize the residual stresses, it is still elusive how to do so by simply optimizing the processing parameters, such as beam size, beam power, and scan speed. Amid different types of additive manufacturing processes, Direct Metal Laser Sintering (DMLS) process uses a high-power laser to melt and sinter layers of metal powder. The rapid solidification and heat transfer on powder bed endows a high cooling rate which leads to the build-up of residual stresses, that will affect the mechanical properties of the build parts. In the present work, the authors develop a numerical thermo-mechanical model for the measurement of residual stress in the AlSi10Mg build samples by using finite element method. Transient temperature distribution in the powder bed was assessed using the coupled thermal to structural model. Subsequently, the residual stresses were estimated with varying laser power. From the simulation result, it found that the melt pool dimensions increase with increasing the laser power and the magnitude of residual stresses in the built part increases.

  17. Effects of organic additives on preferred plane and residual stress of copper electroplated on polyimide

    International Nuclear Information System (INIS)

    Kim, Jongsoo; Kim, Heesan

    2010-01-01

    Effects of the preferred plane and the residual stress of an electroplated copper on polyethylene glycol (PEG) and 3-N,N-dimethylaminodithiocarbamoyl-1-propanesulfonic acid (DPS) were studied. Polyimide film coated with sputtered copper was used as a substrate. Preferred plane, residual stress, and impurity level in the electroplated copper were measured by an X-ray diffractometry (XRD), calculated by Stoney's equation, and analyzed with secondary ion mass spectroscopy (SMS), respectively. With increasing the concentration of PEG, the preferred plane changed in the order (1 0 0) and (1 1 0) while with increasing the concentration of DPS, the preferred plane changed in the order (1 1 0), (1 0 0), and (1 1 1). Based on the modified preferred growth model, where the amount of additive adsorbed on a plane is newly assumed to be proportional to its surface energy in vacuum, the predicted preferred planes correspond to the experimental results. The residual stress of the electroplated copper depended on the type of additive as well as its concentration but was independent of the preferred plane. For example, PEG and DPS induced tensile and compressive residual stresses in the electroplated copper, respectively, and their magnitudes increased with their concentrations. The dependency of residual stress on the additives was explained by the incorporated additives into the electroplated copper.

  18. A novel mutation affecting the arginine-137 residue of AVPR2 in dizygous twins leads to nephrogenic diabetes insipidus and attenuated urine exosome aquaporin-2

    DEFF Research Database (Denmark)

    Hinrichs, Gitte R; Hansen, Louise H; Nielsen, Maria R

    2016-01-01

    Mutations in the vasopressin V2 receptor gene AVPR2 may cause X-linked nephrogenic diabetes insipidus by defective apical insertion of aquaporin-2 in the renal collecting duct principal cell. Substitution mutations with exchange of arginine at codon 137 can cause nephrogenic syndrome...... of inappropriate antidiuresis or congenital X-linked nephrogenic diabetes insipidus. We present a novel mutation in codon 137 within AVPR2 with substitution of glycine for arginine in male dizygotic twins. Nephrogenic diabetes insipidus was demonstrated by water deprivation test and resistance to vasopressin...

  19. L-arginine prevents xanthoma development and inhibits atherosclerosis in LDL receptor knockout mice.

    Science.gov (United States)

    Aji, W; Ravalli, S; Szabolcs, M; Jiang, X C; Sciacca, R R; Michler, R E; Cannon, P J

    1997-01-21

    The potential antiatherosclerotic actions of NO were investigated in four groups of mice (n = 10 per group) lacking functional LDL receptor genes, an animal model of familial hypercholesterolemia. Group 1 was fed a regular chow diet. Groups 2 through 4 were fed a 1.25% high-cholesterol diet. In addition, group 3 received supplemental L-arginine and group 4 received L-arginine and N omega-nitro-L-arginine (L-NA), an inhibitor of NO synthase (NOS). Animals were killed at 6 months; aortas were stained with oil red O for planimetry and with antibodies against constitutive and inducible NOSs. Plasma cholesterol was markedly increased in the animals receiving the high-cholesterol diet. Xanthomas appeared in all mice fed the high-cholesterol diet alone but not in those receiving L-arginine. Aortic atherosclerosis was present in all mice on the high-cholesterol diet. The mean atherosclerotic lesion area was reduced significantly (P < .01) in the cholesterol-fed mice given L-arginine compared with those receiving the high-cholesterol diet alone. The mean atherosclerotic lesion area was significantly larger (P < .01) in cholesterol-fed mice receiving L-arginine + L-NA than in those on the high-cholesterol diet alone. Within the atherosclerotic plaques, endothelial cells immunoreacted for endothelial cell NOS; macrophages, foam cells, and smooth muscle cells immunostained strongly for inducible NOS and nitrotyrosine residues. The data indicate that L-arginine prevents xanthoma formation and reduces atherosclerosis in LDL receptor knockout mice fed a high-cholesterol diet. The abrogation of the beneficial effects of L-arginine by L-NA suggests that the antiatherosclerotic actions of L-arginine are mediated by NOS. The data suggest that L-arginine may be beneficial in familial hypercholesterolemia.

  20. Effect of bentonite addition on residual strength of microwave-hardened waterglass-containing moulding sands

    Directory of Open Access Journals (Sweden)

    M. Stachowicz

    2011-07-01

    Full Text Available The paper presents results of a preliminary research of the effect of bentonite addition on residual strength of microwave-hardened moulding sands, containing sodium waterglass. Strength was determined at ambient temperature, on cylindrical specimens baked in an oven. Moulding sands for examinations were based on high-silica sand with addition of 2.5 % of non-modified, domestic-made waterglass grade 145. The prepared standard cylindrical specimens were hardened using the innovative microwave heating process and next baked for 30 minutes at temperatures between 100 and 1200 °C. Strength parameters of the specimens were determined on the specimens cooled- down to ambient temperature. The obtained results were compared with literature data to evaluate the effect of the applied hardening method and of the special additive on residual strength as a function of baking temperature. A favourable effect was found of both the innovative heating process and the applied bentonite addition.

  1. Arginine Coordination in Enzymatic Phosphoryl Transfer: Evaluation of the Effect of Arg166 Mutations in Escherichia Coli Alkaline Phosphatase

    International Nuclear Information System (INIS)

    O'Brien, P.J.; Lassila, J.K.; Fenn, T.D.; Zalatan, J.G.; Herschlag, D.

    2008-01-01

    Arginine residues are commonly found in the active sites of enzymes catalyzing phosphoryl transfer reactions. Numerous site-directed mutagenesis experiments establish the importance of these residues for efficient catalysis, but their role in catalysis is not clear. To examine the role of arginine residues in the phosphoryl transfer reaction, we have measured the consequences of mutations to arginine 166 in Escherichia coli alkaline phosphatase on hydrolysis of ethyl phosphate, on individual reaction steps in the hydrolysis of the covalent enzyme-phosphoryl intermediate, and on thio substitution effects. The results show that the role of the arginine side chain extends beyond its positive charge, as the Arg166Lys mutant is as compromised in activity as Arg166Ser. Through measurement of individual reaction steps, we construct a free energy profile for the hydrolysis of the enzyme-phosphate intermediate. This analysis indicates that the arginine side chain strengthens binding by ∼3 kcal/mol and provides an additional 1-2 kcal/mol stabilization of the chemical transition state. A 2.1 (angstrom) X-ray diffraction structure of Arg166Ser AP is presented, which shows little difference in enzyme structure compared to the wild-type enzyme but shows a significant reorientation of the bound phosphate. Altogether, these results support a model in which the arginine contributes to catalysis through binding interactions and through additional transition state stabilization that may arise from complementarity of the guanidinum group to the geometry of the trigonal bipyramidal transition state

  2. Addition of residues and reintroduction of microorganisms in Jatropha curcas cultivated in degraded soil

    Directory of Open Access Journals (Sweden)

    Adriana A. Santos

    2016-04-01

    Full Text Available ABSTRACT The aim of this study was to evaluate, through mycorrhization (root colonization and number of spores of arbuscular mycorrhizal fungi - AMF, leaf acid phosphatase and soil chemical characteristics, the effects of the addition of residues (macrophytes and ash, hydrogel and the reintroduction of microorganisms in a degraded area cultivated with jatropha. Degradation occurred when the surface soil was removed during the construction of a hydroelectric power plant. The experiment was set in a randomized block design, using a 2 x 2 x 4 factorial scheme, i.e., two inoculation treatments (with and without soil-inoculum, two hydrogel treatments (with and without and four with the addition of residues (macrophytes - MAC, ash, MAC + ash and control, without residues applied in the planting hole, with 4 replicates and 5 plants in each replicate. Soil from preserved Cerrado area was used as a source of microorganisms, including AMF. The conclusion is that, after 12 months of planting, the hydrogel increased root colonization, while the chemical characteristics of the degraded soil responded positively to the addition of MAC and MAC + ash, with increase in pH and SB and reduction of Al and H + Al. The addition of the soil-inoculum, along with MAC and MAC + ash, promoted higher mycorrhizal colonization and number of spores and reduced amounts of leaf acid phosphatase, indicating increased absorption of P by the host.

  3. An Investigation on In-Vessel Composting of Pistachio Residuals with Different Additions

    OpenAIRE

    M Jalili; M Mokhtari; AA Ebrahimi; F Boghri

    2016-01-01

    Background and Objective: About 1.35×105 tons of pistachio waste are produced in annually Iran that can result in environmental problems if managed improperly. . The purpose of this study was to investigate in-vessel composting of pistachio residuals with addition of cow manure and dewatered sludge as a recycling alternative. Materials and Methods: Pistachios wastes were combined with weight ratio of 5.5:10 (dewatered sludge: pistachio waste) and weight ratio of 1:10 (Cow manure: pi...

  4. Neutron diffraction measurements of residual stress in additively manufactured stainless steel

    International Nuclear Information System (INIS)

    Brown, D.W.; Bernardin, J.D.; Carpenter, J.S.; Clausen, B.; Spernjak, D.; Thompson, J.M.

    2016-01-01

    Charpy test specimens were additively manufactured (AM) on a single stainless steel plate from a 17–4 class stainless steel using a powder-bed, laser melting technique on an EOS M280 direct metal laser sintering (DMLS) machine. Cross-hatched mesh support structures for the Charpy test specimens were varied in strut width and density to parametrically study their influence on the build stability and accuracy as the DMLS process has been known to generate parts with large amounts of residual stress. Neutron diffraction was used to profile the residual stresses in several of the AM samples before and after the samples were removed from the support structure for the purpose of determining residual stresses. The residual stresses were found to depend very little on the properties of the support structure over the limited range studied here. The largest stress component was in the long direction of each of the samples studied and was roughly 2/3 of the yield stress of the material. The stress field was altered considerably when the specimen was removed from the support structure. It was noted in this study that a single Charpy specimen developed a significant tear between the growth plate and support structure. The presence of the tear in the support structure strongly affected the observed stress field: the asymmetric tear resulted in a significantly asymmetric stress field that propagated through removal of the sample from the base plate. The altered final residual stress state of the sample as well as its observed final shape indicates that the tear initiated during the build and developed without disrupting the fabrication process, suggesting a need for in-situ monitoring.

  5. Neutron diffraction measurements of residual stress in additively manufactured stainless steel

    Energy Technology Data Exchange (ETDEWEB)

    Brown, D.W.; Bernardin, J.D.; Carpenter, J.S.; Clausen, B.; Spernjak, D.; Thompson, J.M.

    2016-12-15

    Charpy test specimens were additively manufactured (AM) on a single stainless steel plate from a 17–4 class stainless steel using a powder-bed, laser melting technique on an EOS M280 direct metal laser sintering (DMLS) machine. Cross-hatched mesh support structures for the Charpy test specimens were varied in strut width and density to parametrically study their influence on the build stability and accuracy as the DMLS process has been known to generate parts with large amounts of residual stress. Neutron diffraction was used to profile the residual stresses in several of the AM samples before and after the samples were removed from the support structure for the purpose of determining residual stresses. The residual stresses were found to depend very little on the properties of the support structure over the limited range studied here. The largest stress component was in the long direction of each of the samples studied and was roughly 2/3 of the yield stress of the material. The stress field was altered considerably when the specimen was removed from the support structure. It was noted in this study that a single Charpy specimen developed a significant tear between the growth plate and support structure. The presence of the tear in the support structure strongly affected the observed stress field: the asymmetric tear resulted in a significantly asymmetric stress field that propagated through removal of the sample from the base plate. The altered final residual stress state of the sample as well as its observed final shape indicates that the tear initiated during the build and developed without disrupting the fabrication process, suggesting a need for in-situ monitoring.

  6. Modified Longo's stapled hemorrhoidopexy with additional traction sutures for the treatment of residual prolapsed piles.

    Science.gov (United States)

    Chen, Chuang-Wei; Kang, Jung-Cheng; Wu, Chang-Chieh; Hsiao, Cheng-Wen; Jao, Shu-Wen

    2008-03-01

    Residual prolapsed piles is a problem after the stapled hemorrhoidopexy, especially in large third- or fourth-degree hemorrhoids. We have developed a method using additional traction sutures along with modified Longo's procedure to manage this problem. From January 2005 to October 2005, 30 consecutive patients with symptomatic third- or fourth-degree hemorrhoids who underwent the modified Longo's stapled hemorrhoidopexy with additional traction sutures in a single institution were collected. The demographics, postoperative pain score, surgical features, outcomes, and early and late complications were recorded. All patients were followed for a mean duration of 8.8 (range, 4-15) months. Thirty patients (17 males) with a mean age of 45 (range, 27-63) years were identified. The mean postoperative pain score on the morning of the first postoperative day was 2.8 (range, 1-4). The mean duration of operation was 30.7 (range, 25-37) min. The mean duration of hospital stay was 2 (range, 1-3) days. The mean days for patients to resume normal work was 6.7 (range, 4-9) days. No other procedure-related complications occurred in all patients. There was no early complication except for fecal urgency found in one patient during the first postoperative days. Regarding the late complications, no residual prolapsed piles, persistent anal pain, incontinence, anal stenosis, or recurrent symptoms were found. Our preliminary experiences indicated that this modified procedures truly contributed to reduce the residual internal hemorrhoids and maintained the benefits of stapled hemorrhoidopexy. Randomized trial and long-term follow-up warrant to determine possible surgical and functional outcome.

  7. Treating electrolytic manganese residue with alkaline additives for stabilizing manganese and removing ammonia

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Changbo; Wang, Jiwei [Chinese Research Academy of Environmental Sciences, Beijing (China); Wang, Nanfang [Hunan Institute of Engineering, Xiangtan (China)

    2013-11-15

    Electrolytic manganese residue (EMR) from the electrolytic manganese industry is a solid waste containing mainly calcium sulfate dihydrate and quartzite. It is impossible to directly use the EMR as a building material due to some contaminants such as soluble manganese, ammonia nitrogen and other toxic substances. To immobilize the contaminants and reduce their release into the environment, treating EMR using alkaline additives for stabilizing manganese and removing ammonia was investigated. The physical and chemical characteristics of the original EMR were characterized by XRFS, XRD, and SEM. Leaching test of the original EMR shows that the risks to the environment are the high content of soluble manganese and ammonia nitrogen. The influence of various alkaline additives, solidifying reaction time, and other solidifying reaction conditions such as outdoor ventilation and sunlight, and rain flow on the efficiencies of Mn{sup 2+} solidification and ammonia nitrogen removal was investigated. The results show that with mass ratio of CaO to residue 1 : 8, when the solidifying reaction was carried out indoors for 4 h with no rain flow, the highest efficiencies of Mn{sup 2+} solidification and ammonia nitrogen removal (99.98% and 99.21%) are obtained. Leaching test shows that the concentration and emission of manganese and ammonia nitrogen of the treated EMR meets the requirements of the Chinese government legislation (GB8978-1996)

  8. Treating electrolytic manganese residue with alkaline additives for stabilizing manganese and removing ammonia

    International Nuclear Information System (INIS)

    Zhou, Changbo; Wang, Jiwei; Wang, Nanfang

    2013-01-01

    Electrolytic manganese residue (EMR) from the electrolytic manganese industry is a solid waste containing mainly calcium sulfate dihydrate and quartzite. It is impossible to directly use the EMR as a building material due to some contaminants such as soluble manganese, ammonia nitrogen and other toxic substances. To immobilize the contaminants and reduce their release into the environment, treating EMR using alkaline additives for stabilizing manganese and removing ammonia was investigated. The physical and chemical characteristics of the original EMR were characterized by XRFS, XRD, and SEM. Leaching test of the original EMR shows that the risks to the environment are the high content of soluble manganese and ammonia nitrogen. The influence of various alkaline additives, solidifying reaction time, and other solidifying reaction conditions such as outdoor ventilation and sunlight, and rain flow on the efficiencies of Mn"2"+ solidification and ammonia nitrogen removal was investigated. The results show that with mass ratio of CaO to residue 1 : 8, when the solidifying reaction was carried out indoors for 4 h with no rain flow, the highest efficiencies of Mn"2"+ solidification and ammonia nitrogen removal (99.98% and 99.21%) are obtained. Leaching test shows that the concentration and emission of manganese and ammonia nitrogen of the treated EMR meets the requirements of the Chinese government legislation (GB8978-1996)

  9. Addition of an organic amendment and/or residue mud to bauxite residue sand in order to improve its properties as a growth medium.

    Science.gov (United States)

    Jones, B E H; Haynes, R J; Phillips, I R

    2012-03-01

    The effects of addition of carbonated residue mud (RMC) or seawater neutralized residue mud (RMS), at two rates, in the presence or absence of added green waste compost, on the chemical, physical and microbial properties of gypsum-treated bauxite residue sand were studied in a laboratory incubation study. The growth of two species commonly used in revegetation of residue sand (Lolium rigidum and Acacia saligna) in the treatments was then studied in a 18-week greenhouse study. Addition of green waste-based compost increased ammonium acetate-extractable (exchangeable) Mg, K and Na. Addition of residue mud at 5 and 10% w/w reduced exchangeable Ca but increased that of Mg and Na (and K for RMS). Concentrations of K, Na, Mg and level of EC in saturation paste extracts were increased by residue mud additions. Concentrations of cations in water extracts were considerably higher than those in saturation paste extracts but trends with treatment were broadly similar. Addition of both compost and residue mud caused a significant decrease in macroporosity with a concomitant increase in mesoporosity and microporosity, available water holding capacity and the quantity of water held at field capacity. Increasing rates of added residue mud reduced the percentage of sample present as discrete sand particles and increased that in aggregated form (particularly in the 1-2 and >10mm diameter ranges). Organic C content, C/N ratio, soluble organic C, microbial biomass C and basal respiration were increased by compost additions. Where compost was added, residue mud additions caused a substantial increase in microbial biomass and basal respiration. L. rigidum grew satisfactorily in all treatments although yields tended to be reduced by additions of mud (especially RMC) particularly in the absence of added compost. Growth of A. saligna was poor in sand alone and mud-amended sand and was greatly promoted by additions of compost. However, in the presence of compost, addition of carbonated

  10. UTILIZATION OF CANDEIA (Eremanthus erythropappus WOOD RESIDUES IN THE PRODUCTION OF PARTICLEBOAD WITH ADDITION OF PET

    Directory of Open Access Journals (Sweden)

    Rosimeire Cavalcante dos Santos

    2011-03-01

    Full Text Available This work aimed to evaluate, through the physical and mechanical properties, the panels production viability with inclusion of candeia (Eremanthus erythropappus wood residues and the influence of different percentages of PET (polyethylene terephthalate, as well as the presence and absence of paraffin on the properties of particleboard. There were used candeia wood residues, after oil extraction, in association with eucalypt wood in the proportion of 25:75 and urea-formaldehyde adhesive (12% for panels production; besides the PET incorporation in particle form, which were originated from soft drink bottles and included in three percentages (0%, 25% e 50% in treatments in the presence (1% and absence of paraffin emulsion. The panels pressing cycle occurred under electric heating at 160°C, 0.4 MPa of pressure, during 8 minutes. The experimental design was entirely randomized with three repetitions. The properties evaluated, according to DIN (1971, ASTM D 1037-93 (1995 and CS 236-66 (1968 standards, were: internal bonding; static bending (modulus of elasticity – MOE and rupture – MOR; compression parallel to the panel surface; water absorption and thickness swelling, after 2 and 24 hours water immersion. The panel mechanical properties decreased with increasing in PET level; in general, paraffin addition did not improve the wood/plastic panels resistance and higroscopicity; the utilization of candeia wood residues is viable, in association with eucalypt wood, for the wood/plastic panel production, since the properties attended the minimum demands of the standards, except static bending.

  11. Investigation of some additive residues in bulk raw milk collected from Pakdasht area in 2009

    Directory of Open Access Journals (Sweden)

    T Moosavi

    2011-05-01

    Full Text Available Milk is one of the most important sources of human nutrition and because of high nutrient content; it is a very suitable medium for microbial growth and spoilage. Sometimes farmers cheat and add some additives to milk in order to cover the spoilage or other defects in milk. In this study 120 samples of bulk raw milk (10 samples each month were collected from dairy farms of Pakdasht under sterile condition and send to veterinary faculty of GarmsarUniversity. The following tests were done on each sample: Anti-microbial residues, residues milk acidity neutralizer, evaluation of sugar, formalin, Hydrogen peroxide, Salicylic acid and salt presence. Results were analyzed with Spss software and the results of the first six months of the year were compared statistically with the results of the second six months of the year. The mean of antimicrobial agents, milk acid neutralizer, formalin, hydrogen peroxide and salicylic acid showed no significant difference. But sugar in first semester were more than second semester (p

  12. Residual stress measurements via neutron diffraction of additive manufactured stainless steel 17-4 PH.

    Science.gov (United States)

    Masoomi, Mohammad; Shamsaei, Nima; Winholtz, Robert A; Milner, Justin L; Gnäupel-Herold, Thomas; Elwany, Alaa; Mahmoudi, Mohamad; Thompson, Scott M

    2017-08-01

    Neutron diffraction was employed to measure internal residual stresses at various locations along stainless steel (SS) 17-4 PH specimens additively manufactured via laser-powder bed fusion (L-PBF). Of these specimens, two were rods (diameter=8 mm, length=80 mm) built vertically upward and one a parallelepiped (8×80×9 mm 3 ) built with its longest edge parallel to ground. One rod and the parallelepiped were left in their as-built condition, while the other rod was heat treated. Data presented provide insight into the microstructural characteristics of typical L-PBF SS 17-4 PH specimens and their dependence on build orientation and post-processing procedures such as heat treatment. Data have been deposited in the Data in Brief Dataverse repository (doi:10.7910/DVN/T41S3V).

  13. Residual stress measurements via neutron diffraction of additive manufactured stainless steel 17-4 PH

    Directory of Open Access Journals (Sweden)

    Mohammad Masoomi

    2017-08-01

    Full Text Available Neutron diffraction was employed to measure internal residual stresses at various locations along stainless steel (SS 17-4 PH specimens additively manufactured via laser-powder bed fusion (L-PBF. Of these specimens, two were rods (diameter=8 mm, length=80 mm built vertically upward and one a parallelepiped (8×80×9 mm3 built with its longest edge parallel to ground. One rod and the parallelepiped were left in their as-built condition, while the other rod was heat treated. Data presented provide insight into the microstructural characteristics of typical L-PBF SS 17-4 PH specimens and their dependence on build orientation and post-processing procedures such as heat treatment. Data have been deposited in the Data in Brief Dataverse repository (doi:10.7910/DVN/T41S3V.

  14. POLYMER RESIDUE BASED HYDROPHOBIC-FUNGICIDAL ADDITIVE AND PLASTER DRY MIX BASED ON IT

    Directory of Open Access Journals (Sweden)

    Chikichev Artur Andreevich

    2017-07-01

    Full Text Available Subject of study is the effect of additives on the structure formation of cement. Improvement of the re-sistance to aggressive media of materials for wet rooms. Objective is to develop a scientifically grounded composition of a plaster dry construction mix with increased water resistance and funginertness, with the use of locally available materials and man-made waste.The study was carried out by standard methods of research using XRF and DTA. The hydrophobic fungicidal additive based on the polymer residue of turpentine production and fly ash with the ratio by weight ZU: PO = 1.15: 1 was developed. It has been established that while adding the de-veloped additive in an amount of 2.5 % of the mass of cement, the rate of hydration of cement minerals and resistibility of the sand-cement mortar decrease in early strength with medium workability concrete mix. This creates conditions for the formation of a dense structure with increased resistance to aggressive envi-ronments.Using new hydrophobic fungicidal additive, a dry plaster mortar for wet rooms has been developed. It has increased water resistance values corresponding to the W8 grade and funginertness especially with respect to A. Niger, the pathogen and widespread decomposer.The additive is effective; it is developed on the basis of industrial wastes and recycled materials. Its use in the composition of materials with increased requirements for watertightness and biostability makes it pos-sible to reduce their cost and environmental stress, to increase the efficiency of the use of natural re-sources. The use of the developed plaster mixture will increase the resistance of walls of wet rooms to aggressive environments.

  15. Rmt1 catalyzes zinc-finger independent arginine methylation of ribosomal protein Rps2 in Saccharomyces cerevisiae

    International Nuclear Information System (INIS)

    Lipson, Rebecca S.; Webb, Kristofor J.; Clarke, Steven G.

    2010-01-01

    Rps2/rpS2 is a well conserved protein of the eukaryotic ribosomal small subunit. Rps2 has previously been shown to contain asymmetric dimethylarginine residues, the addition of which is catalyzed by zinc-finger-containing arginine methyltransferase 3 (Rmt3) in the fission yeast Schizosaccharomyces pombe and protein arginine methyltransferase 3 (PRMT3) in mammalian cells. Here, we demonstrate that despite the lack of a zinc-finger-containing homolog of Rmt3/PRMT3 in the budding yeast Saccharomyces cerevisiae, Rps2 is partially modified to generate asymmetric dimethylarginine and monomethylarginine residues. We find that this modification of Rps2 is dependent upon the major arginine methyltransferase 1 (Rmt1) in S. cerevisiae. These results are suggestive of a role for Rmt1 in modifying the function of Rps2 in a manner distinct from that occurring in S. pombe and mammalian cells.

  16. Nutrient assessment of olive leaf residues processed by solid-state fermentation as an innovative feedstuff additive.

    Science.gov (United States)

    Xie, P-J; Huang, L-X; Zhang, C-H; Zhang, Y-L

    2016-07-01

    Olive leaf residue feedstuff additives were prepared by solid-state fermentation (SSF), and its feeding effects on broiler chickens were examined. The fermentation's nutrient value, that is, protein enrichment, cellulase activity, tannic acid degradation and amino acid enhancement, was determined. The effect of different strains, including molds (Aspergillus niger, Aspergillus oryzae and Trichoderma viride) and yeasts (Candida utilis, Candida tropicalis and Geotrichum candidum), and the fermentation time on the nutrient values of the feedstuff additives was investigated. The experimental results showed that the optimal parameters for best performance were A. niger and C. utilis in a 1 : 1 ratio (v/v) in co-culture fermentation for 5 days. Under these conditions, the total content of amino acids in the fermented olive leaf residues increased by 22·0% in comparison with that in the raw leaf residues. Both Glutamic acid and Aspartic acid contents were increased by more than 25·4%. Broiler chickens fed with different amounts of feedstuff additives were assessed. The results demonstrated that the chicken weight gains increased by 120%, and normal serum biochemical parameters were improved significantly after 10% of the feedstuff additives were supplemented to the daily chicken feed for 28 days. The co-culture combination of A. niger and C. utilis with SSF for olive leaf residue had the best nutrient values. The addition of 10% fermented olive leaf residue facilitated the chicken growth and development. This study reveals that olive leaf residues fermented by SSF exhibited considerable potential as feed additives for feeding poultry. © 2016 The Society for Applied Microbiology.

  17. The effects of L-arginine, D-arginine, L-name and methylene blue on channa striatus-induced peripheral antinociception in mice.

    Science.gov (United States)

    Zakaria, Zainul Amiruddin; Sulaiman, Mohd Rosian; Somchit, Muhammad Nazrul; Jais, Abdul Manan Mat; Ali, Daud Israf

    2005-08-03

    To determine the involvement of nitric oxide/cyclic guanosine monophosphate (NO/cGMP) pathway in aqueous supernatant of haruan (Channa striatus) fillet (ASH) antinociception using the acetic acid-induced abdominal constriction test. The ASH was prepared by soaking fresh haruan fillet in chloroform:methanol (CM) (2/1 (v/v)) for 72 h followed by evaporation of the upper layer supernatant to remove any solvent residues. The supernatant was then subjected to a freeze-drying process (48 h) followed by doses preparation. Subcutaneous (SC) administration of ASH alone (0.170, 0.426 and 1.704 mg/kg) exhibited a dose-dependent antinociception. On the other hand, 20 mg/kg (SC) of L-arginine and MB exhibited a significant nociception and antinociception, while D-arginine and L-NAME did not produce any effect at all. Pre-treatment with L-arginine was found to significantly reverse the three respective doses of ASH antinociception; pre-treatment with D-arginine did not produce any significant change in the ASH activity; pre-treatment with L-NAME only significantly increased the 0.170 and 0.426 mg/kg ASH antinociception; and pre-treatment with MB significantly enhanced the respective doses of ASH antinociception, respectively. Furthermore, co-treatment with L-NAME significantly enhanced the L-arginine reversal effect on 0.426 mg/kg ASH antinociception. In addition, MB significantly reversed the L-arginine nociception on 0.426 mg/kg ASH. These finding suggest ASH antinociception involves the nitric oxide (NO)/cyclic guanosine monophosphate (cGMP) pathway. The presence of NO was found to reverse ASH antinociceptive activity while blocking of cGMP system enhanced it.

  18. Short-term impact of dry olive mill residue addition to soil on the resident microbiota

    Czech Academy of Sciences Publication Activity Database

    Sampedro, I.; Giubilei, M. A.; Cajthaml, Tomáš; Federici, E.; Federici, F.; Petruccioli, M.; D´Annibale, A.

    2009-01-01

    Roč. 100, č. 23 (2009), s. 6098-6106 ISSN 0960-8524 R&D Projects: GA MŠk LC06066 Institutional research plan: CEZ:AV0Z50200510 Keywords : Dry olive mill residue * Microbial community profiling * Toxicity Subject RIV: EE - Microbiology, Virology Impact factor: 4.253, year: 2009

  19. Modeling the Influence of Process Parameters and Additional Heat Sources on Residual Stresses in Laser Cladding

    Science.gov (United States)

    Brückner, F.; Lepski, D.; Beyer, E.

    2007-09-01

    In laser cladding thermal contraction of the initially liquid coating during cooling causes residual stresses and possibly cracks. Preweld or postweld heating using inductors can reduce the thermal strain difference between coating and substrate and thus reduce the resulting stress. The aim of this work is to better understand the influence of various thermometallurgical and mechanical phenomena on stress evolution and to optimize the induction-assisted laser cladding process to get crack-free coatings of hard materials at high feed rates. First, an analytical one-dimensional model is used to visualize the most important features of stress evolution for a Stellite coating on a steel substrate. For more accurate studies, laser cladding is simulated including the powder-beam interaction, the powder catchment by the melt pool, and the self-consistent calculation of temperature field and bead shape. A three-dimensional finite element model and the required equivalent heat sources are derived from the results and used for the transient thermomechanical analysis, taking into account phase transformations and the elastic-plastic material behavior with strain hardening. Results are presented for the influence of process parameters such as feed rate, heat input, and inductor size on the residual stresses at a single bead of Stellite coatings on steel.

  20. Effect of Sewage Sludge Addition on the Completion of Aerobic Composting of Thermally Hydrolyzed Kitchen Biogas Residue

    OpenAIRE

    Hong-tao Liu; Lu Cai

    2014-01-01

    The composting of thermal-hydrolyzed kitchen biogas residue, either with or without sewage sludge, was compared in this study. The addition of sewage sludge increased and prolonged the temperature to a sufficient level that met the requirements for aerobic composting. Moreover, after mixing the compost materials, oxygen, ammonia, and carbon dioxide levels reverted to those typical of aerobic composting. Finally, increased dewatering, organic matter degradation, and similar mature compost prod...

  1. Arginine Adjunctive Therapy in Active Tuberculosis

    Directory of Open Access Journals (Sweden)

    Aliasghar Farazi

    2015-01-01

    Full Text Available Background. Dietary supplementation has been used as a mechanism to augment the immune system. Adjunctive therapy with L-arginine has the potential to improve outcomes in active tuberculosis. Methods. In a randomized clinical trial 63 participants with smear-positive pulmonary tuberculosis in Markazi Province of Iran were given arginine or placebo for 4 weeks in addition to conventional chemotherapy. The final treatment success, sputum conversion, weight gain, and clinical symptoms after one and two months were considered as primary outcomes and secondary outcomes were ESR, CRP, and Hg. Data were collected and analyzed with SPSS software (ver. 18. Results. Arginine supplementation reduced constitutional symptoms (P=0.032 in patients with smear-positive TB at the end of the first month of treatment. Arginine treated patients had significantly increased BMI at the end of the first and second months of treatment (P=0.032 and P=0.04 and a reduced CRP at the end of the first month of treatment (P=0.03 versus placebo group. Conclusion. Arginine is useful as an adjunctive therapy in patients with active tuberculosis, in which the effects are more likely mediated by the increased production of nitric oxide and improved constitutional symptoms and weight gain. This trial is registered with Clinical Trials Registry of Iran: IRCT201211179855N2.

  2. Assessment of Nano Cellulose from Peach Palm Residue as Potential Food Additive: Part II: Preliminary Studies.

    Science.gov (United States)

    Andrade, Dayanne Regina Mendes; Mendonça, Márcia Helena; Helm, Cristiane Vieira; Magalhães, Washington L E; de Muniz, Graciela Ines Bonzon; Kestur, Satyanarayana G

    2015-09-01

    High consumption of dietary fibers in the diet is related to the reduction of the risk of non-transmitting of chronic diseases, prevention of the constipation etc. Rich diets in dietary fibers promote beneficial effects for the metabolism. Considering the above and recognizing the multifaceted advantages of nano materials, there have been many attempts in recent times to use the nano materials in the food sector including as food additive. However, whenever new product for human and animal consumption is developed, it has to be tested for their effectiveness regarding improvement in the health of consumers, safety aspects and side effects. However, before it is tried with human beings, normally such materials would be assessed through biological tests on a living organism to understand its effect on health condition of the consumer. Accordingly, based on the authors' finding reported in a previous paper, this paper presents body weight, biochemical (glucose, cholesterol and lipid profile in blood, analysis of feces) and histological tests carried out with biomass based cellulose nano fibrils prepared by the authors for its possible use as food additive. Preliminary results of the study with mice have clearly brought out potential of these fibers for the said purpose.

  3. Asymmetric Arginine dimethylation of Epstein-Barr virus nuclear antigen 2 promotes DNA targeting

    International Nuclear Information System (INIS)

    Gross, Henrik; Barth, Stephanie; Palermo, Richard D.; Mamiani, Alfredo; Hennard, Christine; Zimber-Strobl, Ursula; West, Michelle J.; Kremmer, Elisabeth; Graesser, Friedrich A.

    2010-01-01

    The Epstein-Barr virus (EBV) growth-transforms B-lymphocytes. The virus-encoded nuclear antigen 2 (EBNA2) is essential for transformation and activates gene expression by association with DNA-bound transcription factors such as RBPJκ (CSL/CBF1). We have previously shown that EBNA2 contains symmetrically dimethylated Arginine (sDMA) residues. Deletion of the RG-repeat results in a reduced ability of the virus to immortalise B-cells. We now show that the RG repeat also contains asymmetrically dimethylated Arginines (aDMA) but neither non-methylated (NMA) Arginines nor citrulline residues. We demonstrate that only aDMA-containing EBNA2 is found in a complex with DNA-bound RBPJκ in vitro and preferentially associates with the EBNA2-responsive EBV C, LMP1 and LMP2A promoters in vivo. Inhibition of methylation in EBV-infected cells results in reduced expression of the EBNA2-regulated viral gene LMP1, providing additional evidence that methylation is a prerequisite for DNA-binding by EBNA2 via association with the transcription factor RBPJκ.

  4. Remission of diabetes mellitus in cats cannot be predicted by the arginine stimulation test

    OpenAIRE

    Tschuor, F

    2011-01-01

    Background: Responsiveness of β-cells to arginine persists the longest during diabetes progression, making the intravenous arginine stimulation test (IVAST) a useful tool to assess residual insulin and glucagon secretion. Hypothesis: Diabetic cats with and without remission will have different arginine-induced insulin or glucagon response. Animals: 17 cats with diabetes, 7 healthy cats. Methods: Response to IVAST was assessed by calculating insulin and glucagon area under the c...

  5. The use of sewage sludge as additive to avoid operational problems at combustion of shredder residues

    International Nuclear Information System (INIS)

    Gyllenhammar, Marianne

    2010-01-01

    When shredder light fraction (SLF) from recovery of metal scrap is energy recovered it is usually mixed with more than 90% of other wastes. SLF is a fuel with high energy content but also with relatively high chlorine and metal content and could cause deposit and corrosion problems in incineration plants. Sewage sludge has previously been shown to reduce deposition and corrosion problems in combustion of alkali and chlorine containing biomass. In this work 20 % SLF (by energy content) has been combusted together with municipal solid waste and industrial wastes, with and without addition of 3 % (by energy content) sewage sludge. The initial fireside corrosion rate was then compared to the corrosion rate during combustion of the normal fuel mix, i.e. only municipal solid waste and industrial wastes. The tests were done at the 20 MW fluidized bed boiler of Lidkoping heat production plant. During the tests air-cooled corrosion and deposit probes were exposed for 24 hours. Deposit probes were placed at three different flue gas temperatures - in the combustion chamber, upstream and downstream the convection pass. The corrosion probes were placed upstream the convection pass and on the probes there were three different materials at three different water temperatures (280, 350 and 420 degree Celsius). The tests showed that sewage sludge could help avoiding deposition and corrosion problems when incinerating SLF. The amount of deposits was reduced and the content of the deposits was less corrosive when sewage sludge was added. The project was financed by Waste Refinery as a collaboration project between Stena Metall AB, Metso AB, High Temperature Corrosion Center at Chalmers University of Technology, SP Technical Research Institute of Sweden and Lidkopings Varmeverk. (author)

  6. Anti-aging effects of l-arginine

    Directory of Open Access Journals (Sweden)

    Mohamed Z. Gad

    2010-07-01

    Full Text Available l-Arginine is one of the most metabolically versatile amino acids. In addition to its role in the synthesis of nitric oxide, l-arginine serves as a precursor for the synthesis of polyamines, proline, glutamate, creatine, agmatine and urea. Several human and experimental animal studies have indicated that exogenous l-arginine intake has multiple beneficial pharmacological effects when taken in doses larger than normal dietary consumption. Such effects include reduction in the risk of vascular and heart diseases, reduction in erectile dysfunction, improvement in immune response and inhibition of gastric hyperacidity. This review summarises several positive studies and personal experiences of l-arginine. The demonstrated anti-aging benefits of l-arginine show greater potential than any pharmaceutical or nutraceutical agent ever previously discovered.

  7. On the mechanism of arginine requirement for adenovirus synthesis

    International Nuclear Information System (INIS)

    Plaat, D.; Weber, J.

    1979-01-01

    The effects of arginine deprivation on the synthesis and processing of viral proteins and the assembly of incomplete and complete virions were studied during infection with human adenovirus type 2. Arginine deprivation greatly reduced the synthesis of all viral proteins, particularly the precursor to core protein VII. The inhibition was completely reversible by the addition of arginine to the medium. Arginine deprivation between 7 and 20 hours post-infection inhibited the processing of PVII to VII, suggesting that PVII is not cleaved autocatalytically. The assembly of incomplete virions was sensitive to arginine deprivation only prior to 20 hours, while the assembly of complete virions was dependent on the continuous presence of arginine. This observation supports the hypothesis that incomplete virions are precursors of complete virions. The experiments on the PVII-specific endoprotease activity showed that arginine deprivation caused only slight reduction in the in vitro activity, although no activity was observed in vivo. The present results lead to the hypothesis that arginine deficiency inhibits the synthesis of a functional protein essential for virion maturation, other than the synthesis of processing of PVII. (author)

  8. Recycling of drinking water treatment residue as an additional medium in columns for effective P removal from eutrophic surface water.

    Science.gov (United States)

    Wang, Changhui; Wu, Yu; Bai, Leilei; Zhao, Yaqian; Yan, Zaisheng; Jiang, Helong; Liu, Xin

    2018-07-01

    This study assesses the feasibility of recycling drinking water treatment residue (DWTR) to treat eutrophic surface water in a one-year continuous flow column test. Heat-treated DWTR was used as an additional medium (2%-4%) in columns in case excessive organic matter and N were released from the DWTR to surface water. The results indicated that with minimal undesirable effects on other water properties, DWTR addition substantially enhanced P removal, rendering P concentrations in treated water oligotrophic and treated water unsuitable for Microcystis aeruginosa breeding. Long-term stable P removal by DWTR-column treatment was mainly attributed to the relatively low P levels in raw water (cycles and multiple pollution control (e.g., Dechloromonas, Geobacter, Leucobacter, Nitrospira, Rhodoplanes, and Sulfuritalea); an apparent decrease in Mycobacterium with potential pathogenicity was observed in DWTR-columns. Regardless, limited denitrification of DWTR-columns was observed as a result of low bioavailability of C in surface water. This finding indicates that DWTR can be used with other methods to ensure denitrification for enhanced treatment effects. Overall, the use of DWTR as an additional medium in column systems can potentially treat eutrophic surface water. Copyright © 2018 Elsevier Ltd. All rights reserved.

  9. Analysis of an Alanine/Arginine Mixture by Using TLC/FTIR Technique

    Directory of Open Access Journals (Sweden)

    Jun Liu

    2014-01-01

    Full Text Available We applied TLC/FTIR coupled with mapping technique to analyze an alanine/arginine mixture. Narrow band TLC plates prepared by using AgI as a stationary phase were used to separate alanine and arginine. The distribution of alanine and arginine spots was manifested by a 3D chromatogram. Alanine and arginine can be successfully separated by the narrow band TLC plate. In addition, the FTIR spectra of the separated alanine and arginine spots on the narrow band TLC plate are roughly the same as the corresponding reference IR spectra.

  10. Drosophila arginine methyltransferase 1 (DART1) is an ecdysone receptor co-repressor

    International Nuclear Information System (INIS)

    Kimura, Shuhei; Sawatsubashi, Shun; Ito, Saya; Kouzmenko, Alexander; Suzuki, Eriko; Zhao, Yue; Yamagata, Kaoru; Tanabe, Masahiko; Ueda, Takashi; Fujiyama, Sari; Murata, Takuya; Matsukawa, Hiroyuki; Takeyama, Ken-ichi; Yaegashi, Nobuo

    2008-01-01

    Histone arginine methylation is an epigenetic marker that regulates gene expression by defining the chromatin state. Arginine methyltransferases, therefore, serve as transcriptional co-regulators. However, unlike other transcriptional co-regulators, the physiological roles of arginine methyltransferases are poorly understood. Drosophila arginine methyltransferase 1 (DART1), the mammalian PRMT1 homologue, methylates the arginine residue of histone H4 (H4R3me2). Disruption of DART1 in Drosophila by imprecise P-element excision resulted in low viability during metamorphosis in the pupal stages. In the pupal stage, an ecdysone hormone signal is critical for developmental progression. DART1 interacted with the nuclear ecdysone receptor (EcR) in a ligand-dependent manner, and co-repressed EcR in intact flies. These findings suggest that DART1, a histone arginine methyltransferase, is a co-repressor of EcR that is indispensable for normal pupal development in the intact fly

  11. A Promising Material by Using Residue Waste from Bisphenol A Manufacturing to Prepare Fluid-Loss-Control Additive in Oil Well Drilling Fluid

    Directory of Open Access Journals (Sweden)

    Zhi-Lei Zhang

    2013-01-01

    Full Text Available The residues mixture from Bisphenol A manufacturing process was analyzed. Fourier transform infrared (FTIR spectroscopy, gas chromatography-mass spectrometry (GC-MS, and nuclear magnetic resonance (NMR were used to characterize the residues. The results indicated that the residues were complex mixture of several molecules. 3-(2-Hydroxyphenyl-1,1,3-trimethyl-2,3-dihydro-1H-inden-5-ol and phenol were the main components of the residues. The technical feasibility of using it as phenol replacement in fluid-loss-control additive production was also investigated. The fluid-loss-control capacity of the novel additive was systematically investigated. It was discovered that the well fluid-loss performance of the prepared additive can be achieved, especially at high temperature.

  12. Effect of water treatment additives on lime softening residual trace chemical composition--implications for disposal and reuse.

    Science.gov (United States)

    Cheng, Weizhi; Roessler, Justin; Blaisi, Nawaf I; Townsend, Timothy G

    2014-12-01

    Drinking water treatment residues (WTR) offer potential benefits when recycled through land application. The current guidance in Florida, US allows for unrestricted land application of lime softening WTR; alum and ferric WTR require additional evaluation of total and leachable concentrations of select trace metals prior to land application. In some cases a mixed WTR is produced when lime softening is accompanied by the addition of a coagulant or other treatment chemical; applicability of the current guidance is unclear. The objective of this research was to characterize the total and leachable chemical content of WTR from Florida facilities that utilize multiple treatment chemicals. Lime and mixed lime WTR samples were collected from 18 water treatment facilities in Florida. Total and leachable concentrations of the WTR were measured. To assess the potential for disposal of mixed WTR as clean fill below the water table, leaching tests were conducted at multiple liquid to solid ratios and under reducing conditions. The results were compared to risk-based soil and groundwater contamination thresholds. Total metal concentrations of WTR were found to be below Florida soil contaminant thresholds with Fe found in the highest abundance at a concentration of 3600 mg/kg-dry. Aluminum was the only element that exceeded the Florida groundwater contaminant thresholds using SPLP (95% UCL = 0.23 mg/L; risk threshold = 0.2 mg/L). Tests under reducing conditions showed elevated concentrations of Fe and Mn, ranging from 1 to 3 orders of magnitude higher than SPLP leachates. Mixed lime WTR concentrations (total and leachable) were lower than the ferric and alum WTR concentrations, supporting that mixed WTR are appropriately represented as lime WTR. Testing of WTR under reducing conditions demonstrated the potential for release of certain trace metals (Fe, Al, Mn) above applicable regulatory thresholds; additional evaluation is needed to assess management options where

  13. Dietary arginine and linear growth

    DEFF Research Database (Denmark)

    van Vught, Anneke J A H; Dagnelie, Pieter C; Arts, Ilja C W

    2013-01-01

    Child Intervention Study during 2001-2 (baseline), and at 3-year and 7-year follow-up, were used. Arginine intake was estimated via a 7 d precoded food diary at baseline and 3-year follow-up. Data were analysed in a multilevel structure in which children were embedded within schools. Random intercept......The amino acid arginine is a well-known growth hormone (GH) stimulator and GH is an important modulator of linear growth. The aim of the present study was to investigate the effect of dietary arginine on growth velocity in children between 7 and 13 years of age. Data from the Copenhagen School...... and slopes were defined to estimate the association between arginine intake and growth velocity, including the following covariates: sex; age; baseline height; energy intake; puberty stage at 7-year follow-up and intervention/control group. The association between arginine intake and growth velocity...

  14. Combinatorial effects of arginine and fluoride on oral bacteria.

    Science.gov (United States)

    Zheng, X; Cheng, X; Wang, L; Qiu, W; Wang, S; Zhou, Y; Li, M; Li, Y; Cheng, L; Li, J; Zhou, X; Xu, X

    2015-02-01

    Dental caries is closely associated with the microbial disequilibrium between acidogenic/aciduric pathogens and alkali-generating commensal residents within the dental plaque. Fluoride is a widely used anticaries agent, which promotes tooth hard-tissue remineralization and suppresses bacterial activities. Recent clinical trials have shown that oral hygiene products containing both fluoride and arginine possess a greater anticaries effect compared with those containing fluoride alone, indicating synergy between fluoride and arginine in caries management. Here, we hypothesize that arginine may augment the ecological benefit of fluoride by enriching alkali-generating bacteria in the plaque biofilm and thus synergizes with fluoride in controlling dental caries. Specifically, we assessed the combinatory effects of NaF/arginine on planktonic and biofilm cultures of Streptococcus mutans, Streptococcus sanguinis, and Porphyromonas gingivalis with checkerboard microdilution assays. The optimal NaF/arginine combinations were selected, and their combinatory effects on microbial composition were further examined in single-, dual-, and 3-species biofilm using bacterial species-specific fluorescence in situ hybridization and quantitative polymerase chain reaction. We found that arginine synergized with fluoride in suppressing acidogenic S. mutans in both planktonic and biofilm cultures. In addition, the NaF/arginine combination synergistically reduced S. mutans but enriched S. sanguinis within the multispecies biofilms. More importantly, the optimal combination of NaF/arginine maintained a "streptococcal pressure" against the potential growth of oral anaerobe P. gingivalis within the alkalized biofilm. Taken together, we conclude that the combinatory application of fluoride and arginine has a potential synergistic effect in maintaining a healthy oral microbial equilibrium and thus represents a promising ecological approach to caries management. © International & American

  15. Bioinformatic evaluation of L-arginine catabolic pathways in 24 cyanobacteria and transcriptional analysis of genes encoding enzymes of L-arginine catabolism in the cyanobacterium Synechocystis sp. PCC 6803

    Directory of Open Access Journals (Sweden)

    Pistorius Elfriede K

    2007-11-01

    Full Text Available Abstract Background So far very limited knowledge exists on L-arginine catabolism in cyanobacteria, although six major L-arginine-degrading pathways have been described for prokaryotes. Thus, we have performed a bioinformatic analysis of possible L-arginine-degrading pathways in cyanobacteria. Further, we chose Synechocystis sp. PCC 6803 for a more detailed bioinformatic analysis and for validation of the bioinformatic predictions on L-arginine catabolism with a transcript analysis. Results We have evaluated 24 cyanobacterial genomes of freshwater or marine strains for the presence of putative L-arginine-degrading enzymes. We identified an L-arginine decarboxylase pathway in all 24 strains. In addition, cyanobacteria have one or two further pathways representing either an arginase pathway or L-arginine deiminase pathway or an L-arginine oxidase/dehydrogenase pathway. An L-arginine amidinotransferase pathway as a major L-arginine-degrading pathway is not likely but can not be entirely excluded. A rather unusual finding was that the cyanobacterial L-arginine deiminases are substantially larger than the enzymes in non-photosynthetic bacteria and that they are membrane-bound. A more detailed bioinformatic analysis of Synechocystis sp. PCC 6803 revealed that three different L-arginine-degrading pathways may in principle be functional in this cyanobacterium. These are (i an L-arginine decarboxylase pathway, (ii an L-arginine deiminase pathway, and (iii an L-arginine oxidase/dehydrogenase pathway. A transcript analysis of cells grown either with nitrate or L-arginine as sole N-source and with an illumination of 50 μmol photons m-2 s-1 showed that the transcripts for the first enzyme(s of all three pathways were present, but that the transcript levels for the L-arginine deiminase and the L-arginine oxidase/dehydrogenase were substantially higher than that of the three isoenzymes of L-arginine decarboxylase. Conclusion The evaluation of 24

  16. Insight on an arginine synthesis metabolon from the tetrameric structure of yeast acetylglutamate kinase.

    Science.gov (United States)

    de Cima, Sergio; Gil-Ortiz, Fernando; Crabeel, Marjolaine; Fita, Ignacio; Rubio, Vicente

    2012-01-01

    N-acetyl-L-glutamate kinase (NAGK) catalyzes the second, generally controlling, step of arginine biosynthesis. In yeasts, NAGK exists either alone or forming a metabolon with N-acetyl-L-glutamate synthase (NAGS), which catalyzes the first step and exists only within the metabolon. Yeast NAGK (yNAGK) has, in addition to the amino acid kinase (AAK) domain found in other NAGKs, a ~150-residue C-terminal domain of unclear significance belonging to the DUF619 domain family. We deleted this domain, proving that it stabilizes yNAGK, slows catalysis and modulates feed-back inhibition by arginine. We determined the crystal structures of both the DUF619 domain-lacking yNAGK, ligand-free as well as complexed with acetylglutamate or acetylglutamate and arginine, and of complete mature yNAGK. While all other known arginine-inhibitable NAGKs are doughnut-like hexameric trimers of dimers of AAK domains, yNAGK has as central structure a flat tetramer formed by two dimers of AAK domains. These dimers differ from canonical AAK dimers in the -110° rotation of one subunit with respect to the other. In the hexameric enzymes, an N-terminal extension, found in all arginine-inhibitable NAGKs, forms a protruding helix that interlaces the dimers. In yNAGK, however, it conforms a two-helix platform that mediates interdimeric interactions. Arginine appears to freeze an open inactive AAK domain conformation. In the complete yNAGK structure, two pairs of DUF619 domains flank the AAK domain tetramer, providing a mechanism for the DUF619 domain modulatory functions. The DUF619 domain exhibits the histone acetyltransferase fold, resembling the catalytic domain of bacterial NAGS. However, the putative acetyl CoA site is blocked, explaining the lack of NAGS activity of yNAGK. We conclude that the tetrameric architecture is an adaptation to metabolon formation and propose an organization for this metabolon, suggesting that yNAGK may be a good model also for yeast and human NAGSs.

  17. Insight on an arginine synthesis metabolon from the tetrameric structure of yeast acetylglutamate kinase.

    Directory of Open Access Journals (Sweden)

    Sergio de Cima

    Full Text Available N-acetyl-L-glutamate kinase (NAGK catalyzes the second, generally controlling, step of arginine biosynthesis. In yeasts, NAGK exists either alone or forming a metabolon with N-acetyl-L-glutamate synthase (NAGS, which catalyzes the first step and exists only within the metabolon. Yeast NAGK (yNAGK has, in addition to the amino acid kinase (AAK domain found in other NAGKs, a ~150-residue C-terminal domain of unclear significance belonging to the DUF619 domain family. We deleted this domain, proving that it stabilizes yNAGK, slows catalysis and modulates feed-back inhibition by arginine. We determined the crystal structures of both the DUF619 domain-lacking yNAGK, ligand-free as well as complexed with acetylglutamate or acetylglutamate and arginine, and of complete mature yNAGK. While all other known arginine-inhibitable NAGKs are doughnut-like hexameric trimers of dimers of AAK domains, yNAGK has as central structure a flat tetramer formed by two dimers of AAK domains. These dimers differ from canonical AAK dimers in the -110° rotation of one subunit with respect to the other. In the hexameric enzymes, an N-terminal extension, found in all arginine-inhibitable NAGKs, forms a protruding helix that interlaces the dimers. In yNAGK, however, it conforms a two-helix platform that mediates interdimeric interactions. Arginine appears to freeze an open inactive AAK domain conformation. In the complete yNAGK structure, two pairs of DUF619 domains flank the AAK domain tetramer, providing a mechanism for the DUF619 domain modulatory functions. The DUF619 domain exhibits the histone acetyltransferase fold, resembling the catalytic domain of bacterial NAGS. However, the putative acetyl CoA site is blocked, explaining the lack of NAGS activity of yNAGK. We conclude that the tetrameric architecture is an adaptation to metabolon formation and propose an organization for this metabolon, suggesting that yNAGK may be a good model also for yeast and human NAGSs.

  18. Characterizing chronic and acute health risks of residues of veterinary drugs in food: latest methodological developments by the joint FAO/WHO expert committee on food additives.

    Science.gov (United States)

    Boobis, Alan; Cerniglia, Carl; Chicoine, Alan; Fattori, Vittorio; Lipp, Markus; Reuss, Rainer; Verger, Philippe; Tritscher, Angelika

    2017-11-01

    The risk assessment of residues of veterinary drugs in food is a field that continues to evolve. The toxicological end-points to be considered are becoming more nuanced and in light of growing concern about the development of antimicrobial resistance, detailed analysis of the antimicrobial activity of the residues of veterinary drugs in food is increasingly incorporated in the assessment. In recent years, the Joint FAO/WHO Expert Committee on Food Additives (JECFA) has refined its approaches to provide a more comprehensive and fit-for-purpose risk assessment. This publication describes in detail the consideration of acute and chronic effects, the estimation of acute and chronic dietary exposure, current approaches for including microbiological endpoints in the risk assessment, and JECFA's considerations for the potential effects of food processing on residues from veterinary drugs. JECFA now applies these approaches in the development of health-based guidance values (i.e. safe exposure levels) for residues of veterinary drugs. JECFA, thus, comprehensively addresses acute and chronic risks by using corresponding estimates for acute and chronic exposure and suitable correction for the limited bioavailability of bound residues by the Gallo-Torres model. On a case-by-case basis, JECFA also considers degradation products that occur from normal food processing of food containing veterinary drug residues. These approaches will continue to be refined to ensure the most scientifically sound basis for the establishment of health-based guidance values for veterinary drug residues.

  19. Evaluation of certain veterinary drug residues in food. Seventy-eighth report of the Joint FAO/WHO Expert Committee on Food Additives.

    Science.gov (United States)

    2014-01-01

    This report represents the conclusions of a Joint FAO/WHO Expert Committee convened to evaluate the safety of residues of certain veterinary drugs in food and to recommend maximum levels for such residues of food. The first part of the report considers general principles regarding the evaluation of residues of veterinary drugs within the terms of reference of the Joint FAO/WHO Expert Committee on Food Additives (JECFA), including extrapolation of maximum residue limits (MRLs) to minor species, MRLs for veterinary drug residues in honey, MRLs relating to fish and fish species, dietary exposure assessment methodologies, the decision-tree approach to the evaluation of residues of veterinary drugs and guidance for JECFA experts. Summaries follow of the Committee's evaluations of toxicology and residue data on a variety of veterinary drugs: two anthelminthic agents (derquantel, monepantel), three antiparasitic agents (emanectin benzoate, ivermectin, lasalocid sodium), one antibacterial, antifungal and anthelminthic agent (gentian violet), a production aid (recombinant bovine somatotropins) and an adrenoceptor agonist and growth promoter (zilpaterol hydorchloride). Annexed to the report is a summary of the Committee's recommendations on these drugs, including acceptable daily intakes (ADIs)) and proposed MRLs.

  20. Preparation of arginine (guanide 14C)

    International Nuclear Information System (INIS)

    Pichat, L.; Baret, C.

    1960-01-01

    Reaction of anhydrous ammoniac at 800 deg. C on 14 CO 3 Ba gives rise to barium cyanamide 14 C with a yield of about 98 per cent. Addition on H 2 S on cyanamide 14 C leads to thiourea 14 C with a 85 per cent yield, which is quantitatively transformed into S-ethyl-isothiouronium iodide by treatment with methyl iodide. This 14 C-isothiouronium salt is used to introduce 14 C guanide group in α-N-tosyl-ornithine; tosyl group in α-N-tosyl-arginine thus obtained is then removed by hydrolysis with hydrochloric acid. Arginine is separated as flavianic acid salt and is purified on exchange resin Dowex-50. The overall yield based on 14 CO 3 Ba is 25 per cent. (author) [fr

  1. Mutation of exposed hydrophobic amino acids to arginine to increase protein stability

    Directory of Open Access Journals (Sweden)

    Czaplicki Jerzy

    2004-07-01

    Full Text Available Abstract Background One strategy to increase the stability of proteins is to reduce the area of water-accessible hydrophobic surface. Results In order to test it, we replaced 14 solvent-exposed hydrophobic residues of acetylcholinesterase by arginine. The stabilities of the resulting proteins were tested using denaturation by high temperature, organic solvents, urea and by proteolytic digestion. Conclusion Altough the mutational effects were rather small, this strategy proved to be successful since half of the mutants showed an increased stability. This stability may originate from the suppression of unfavorable interactions of nonpolar residues with water or from addition of new hydrogen bonds with the solvent. Other mechanisms may also contribute to the increased stability observed with some mutants. For example, introduction of a charge at the surface of the protein may provide a new coulombic interaction on the protein surface.

  2. Characterisation of neuroprotective efficacy of modified poly-arginine-9 (R9) peptides using a neuronal glutamic acid excitotoxicity model.

    Science.gov (United States)

    Edwards, Adam B; Anderton, Ryan S; Knuckey, Neville W; Meloni, Bruno P

    2017-02-01

    In a recent study, we highlighted the importance of cationic charge and arginine residues for the neuroprotective properties of poly-arginine and arginine-rich peptides. In this study, using cortical neuronal cultures and an in vitro glutamic acid excitotoxicity model, we examined the neuroprotective efficacy of different modifications to the poly-arginine-9 peptide (R9). We compared an unmodified R9 peptide with R9 peptides containing the following modifications: (i) C-terminal amidation (R9-NH2); (ii) N-terminal acetylation (Ac-R9); (iii) C-terminal amidation with N-terminal acetylation (Ac-R9-NH2); and (iv) C-terminal amidation with D-amino acids (R9D-NH2). The three C-terminal amidated peptides (R9-NH2, Ac-R9-NH2, and R9D-NH2) displayed neuroprotective effects greater than the unmodified R9 peptide, while the N-terminal acetylated peptide (Ac-R9) had reduced efficacy. Using the R9-NH2 peptide, neuroprotection could be induced with a 10 min peptide pre-treatment, 1-6 h before glutamic acid insult, or when added to neuronal cultures up to 45 min post-insult. In addition, all peptides were capable of reducing glutamic acid-mediated neuronal intracellular calcium influx, in a manner that reflected their neuroprotective efficacy. This study further highlights the neuroprotective properties of poly-arginine peptides and provides insight into peptide modifications that affect efficacy.

  3. Residual tumor size and IGCCCG risk classification predict additional vascular procedures in patients with germ cell tumors and residual tumor resection: a multicenter analysis of the German Testicular Cancer Study Group.

    Science.gov (United States)

    Winter, Christian; Pfister, David; Busch, Jonas; Bingöl, Cigdem; Ranft, Ulrich; Schrader, Mark; Dieckmann, Klaus-Peter; Heidenreich, Axel; Albers, Peter

    2012-02-01

    Residual tumor resection (RTR) after chemotherapy in patients with advanced germ cell tumors (GCT) is an important part of the multimodal treatment. To provide a complete resection of residual tumor, additional surgical procedures are sometimes necessary. In particular, additional vascular interventions are high-risk procedures that require multidisciplinary planning and adequate resources to optimize outcome. The aim was to identify parameters that predict additional vascular procedures during RTR in GCT patients. A retrospective analysis was performed in 402 GCT patients who underwent 414 RTRs in 9 German Testicular Cancer Study Group (GTCSG) centers. Overall, 339 of 414 RTRs were evaluable with complete perioperative data sets. The RTR database was queried for additional vascular procedures (inferior vena cava [IVC] interventions, aortic prosthesis) and correlated to International Germ Cell Cancer Collaborative Group (IGCCCG) classification and residual tumor volume. In 40 RTRs, major vascular procedures (23 IVC resections with or without prosthesis, 11 partial IVC resections, and 6 aortic prostheses) were performed. In univariate analysis, the necessity of IVC intervention was significantly correlated with IGCCCG (14.1% intermediate/poor vs 4.8% good; p=0.0047) and residual tumor size (3.7% size risk features must initially be identified as high-risk patients for vascular procedures and therefore should be referred to specialized surgical centers with the ad hoc possibility of vascular interventions. Copyright © 2011 European Association of Urology. Published by Elsevier B.V. All rights reserved.

  4. Arginine does not exacerbate markers of inflammation in cocultures of human enterocytes and leukocytes

    DEFF Research Database (Denmark)

    Parlesak, Alexandr; Negrier, I.; Neveux, N.

    2007-01-01

    with arginine did not affect epithelial integrity, production of any of the cytokines investigated, or the amount of nitric oxide. The amino acid used primarily by nonstimulated intestinal epithelial cells cocultured with leukocytes was glutamine. Activation of IEC with bacteria significantly enhanced...... the catabolism of serine, asparagine, and lysine, and reduced glutamine catabolism. Addition of arginine increased ornithine formation and moderately reduced transepithelial transport of methionine and other amino acids. Hence, arginine supplementation does not interfere with inflammation-associated cross...

  5. Evaluation of certain veterinary drug residues in food. Eighty-first report of the Joint FAO/WHO Expert Committee on Food Additives.

    Science.gov (United States)

    2016-01-01

    This report represents the conclusions of a Joint FAO/WHO Expert Committee convened to evaluate the safety of residues of certain veterinary drugs in food and to recommend maximum levels for such residues in food. The first part of the report considers general principles regarding the evaluation of residues of veterinary drugs within the terms of reference of the Joint FAO/WHO Expert Committee on Food Additives (JECFA), including MRLs for generic fish species, acute reference doses (ARfDs) for veterinary drugs, an approach for dietary exposure assessment of compounds used for multiple purposes (i.e veterinary drugs and pesticides), dietary exposure assessment for less-than-lifetime exposure, and the assessment of short-term (90-day and 12-month) studies in dogs. Summaries follow of the Committee's evaluations of toxicological and residue data on a variety of veterinary drugs: two insecticides (diflubenzuron and teflubenzuron), an antiparasitic agent (ivermectin), an ectoparasiticide (sisapronil) and a β2-adrenoceptor agonist (zilpaterol hydrochloride). In addition, the Committee considered issues raised in concern forms from the Codex Committee on Residues of Veterinary Drugs in Foods on lasalocid sodium, an antiparasitic agent. Annexed to the report is a summary of the Committee's recommendations on these drugs, including acceptable daily intakes (ADIs), ARfDs and proposed MRLs.

  6. Residual Sorption and leaching of the herbicide diuron following de-oiled two-phase olive mill waste addition to soil

    Energy Technology Data Exchange (ETDEWEB)

    Lopez-Pineiro, A.; Albarran, A.; Cabrera, D.; Rato, J. M.; Munoz, A.; Flores, S.

    2009-07-01

    The residual sorption, desorption, degradation, and leaching of the herbicide diuron (3-(3,4-dichlorophenyl)-1,1-dimethylurea) a herbicide widely used in olive groves, was studied following the addition to soils of de oiled two-phase olive mill waste (DTPOMW). Field experiments were conducted on an olive grove soil amended over seven years with DTPOMW. (Author)

  7. Residual Sorption and leaching of the herbicide diuron following de-oiled two-phase olive mill waste addition to soil

    International Nuclear Information System (INIS)

    Lopez-Pineiro, A.; Albarran, A.; Cabrera, D.; Rato, J. M.; Munoz, A.; Flores, S.

    2009-01-01

    The residual sorption, desorption, degradation, and leaching of the herbicide diuron (3-(3,4-dichlorophenyl)-1,1-dimethylurea) a herbicide widely used in olive groves, was studied following the addition to soils of de oiled two-phase olive mill waste (DTPOMW). Field experiments were conducted on an olive grove soil amended over seven years with DTPOMW. (Author)

  8. Dietary arginine depletion reduces depressive-like responses in male, but not female, mice.

    Science.gov (United States)

    Workman, Joanna L; Weber, Michael D; Nelson, Randy J

    2011-09-30

    Previous behavioral studies have manipulated nitric oxide (NO) production either by pharmacological inhibition of its synthetic enzyme, nitric oxide synthase (NOS), or by deletion of the genes that code for NOS. However manipulation of dietary intake of the NO precursor, L-arginine, has been understudied in regard to behavioral regulation. L-Arginine is a common amino acid present in many mammalian diets and is essential during development. In the brain L-arginine is converted into NO and citrulline by the enzyme, neuronal NOS (nNOS). In Experiment 1, paired mice were fed a diet comprised either of an L-arginine-depleted, L-arginine-supplemented, or standard level of L-arginine during pregnancy. Offspring were continuously fed the same diets and were tested in adulthood in elevated plus maze, forced swim, and resident-intruder aggression tests. L-Arginine depletion reduced depressive-like responses in male, but not female, mice and failed to significantly alter anxiety-like or aggressive behaviors. Arginine depletion throughout life reduced body mass overall and eliminated the sex difference in body mass. Additionally, arginine depletion significantly increased corticosterone concentrations, which negatively correlated with time spent floating. In Experiment 2, adult mice were fed arginine-defined diets two weeks prior to and during behavioral testing, and again tested in the aforementioned tests. Arginine depletion reduced depressive-like responses in the forced swim test, but did not alter behavior in the elevated plus maze or the resident intruder aggression test. Corticosterone concentrations were not altered by arginine diet manipulation in adulthood. These results indicate that arginine depletion throughout development, as well as during a discrete period during adulthood ameliorates depressive-like responses. These results may yield new insights into the etiology and sex differences of depression. Copyright © 2011 Elsevier B.V. All rights reserved.

  9. Proteome-wide analysis of arginine monomethylation reveals widespread occurrence in human cells

    DEFF Research Database (Denmark)

    Larsen, Sara C; Sylvestersen, Kathrine B; Mund, Andreas

    2016-01-01

    to the frequency of somatic mutations at arginine methylation sites throughout the proteome, we observed that somatic mutations were common at arginine methylation sites in proteins involved in mRNA splicing. Furthermore, in HeLa and U2OS cells, we found that distinct arginine methyltransferases differentially...... kidney 293 cells, indicating that the occurrence of this modification is comparable to phosphorylation and ubiquitylation. A site-level conservation analysis revealed that arginine methylation sites are less evolutionarily conserved compared to arginines that were not identified as modified...... as coactivator-associated arginine methyltransferase 1 (CARM1)] or PRMT1 increased the RNA binding function of HNRNPUL1. High-content single-cell imaging additionally revealed that knocking down CARM1 promoted the nuclear accumulation of SRSF2, independent of cell cycle phase. Collectively, the presented human...

  10. Arginine Improves pH Homeostasis via Metabolism and Microbiome Modulation.

    Science.gov (United States)

    Agnello, M; Cen, L; Tran, N C; Shi, W; McLean, J S; He, X

    2017-07-01

    Dental caries can be described as a dysbiosis of the oral microbial community, in which acidogenic, aciduric, and acid-adapted bacterial species promote a pathogenic environment, leading to demineralization. Alkali generation by oral microbes, specifically via arginine catabolic pathways, is an essential factor in maintaining plaque pH homeostasis. There is evidence that the use of arginine in dentifrices helps protect against caries. The aim of the current study was to investigate the mechanistic and ecological effect of arginine treatment on the oral microbiome and its regulation of pH dynamics, using an in vitro multispecies oral biofilm model that was previously shown to be highly reflective of the in vivo oral microbiome. Pooled saliva from 6 healthy subjects was used to generate overnight biofilms, reflecting early stages of biofilm maturation. First, we investigated the uptake of arginine by the cells of the biofilm as well as the metabolites generated. We next explored the effect of arginine on pH dynamics by pretreating biofilms with 75 mM arginine, followed by the addition of sucrose (15 mM) after 0, 6, 20, or 48 h. pH was measured at each time point and biofilms were collected for 16S sequencing and targeted arginine quantification, and supernatants were prepared for metabolomic analysis. Treatment with only sucrose led to a sustained pH drop from 7 to 4.5, while biofilms treated with sucrose after 6, 20, or 48 h of preincubation with arginine exhibited a recovery to higher pH. Arginine was detected within the cells of the biofilms, indicating active uptake, and arginine catabolites citrulline, ornithine, and putrescine were detected in supernatants, indicating active metabolism. Sequencing analysis revealed a shift in the microbial community structure in arginine-treated biofilms as well as increased species diversity. Overall, we show that arginine improved pH homeostasis through a remodeling of the oral microbial community.

  11. Activities of arginine and ornithine decarboxylases in various plant species.

    Science.gov (United States)

    Birecka, H; Bitonti, A J; McCann, P P

    1985-10-01

    In extracts from the youngest leaves of Avena sativa, Hordeum vulgare, Zea Mays, Pisum sativum, Phaseolus vulgaris, Lactuca sativa, and four pyrrolizidine alkaloid-bearing species of Heliotropium, the activities of ornithine decarboxylase, close to V(max), ranged between traces and 1.5 nanomoles per hour per gram fresh weight when based on putrescine formed during incubation with labeled ornithine. The arginine decarboxylase activities in the same extracts ranged between 8 and 8000 nanomoles per hour per gram fresh weight being lowest in the borages and highest in oat and barley. alpha-Difluoromethylornithine and alpha-difluoromethylarginine inhibited ornithine and arginine decarboxylases, respectively, in all species. Agmatine, putrescine, spermidine, and spermine were found in all, diaminopropane in eight, and cadaverine in three species.No correlation was observed between arginine or ornithine decarboxylase level and the levels of total polyamines. The in vitro decarboxylase activities found in the borages cannot explain the high accumulation of putrescine-derived pyrrolizidines in their youngest leaves if the pyrrolizidines are produced in situ from arginine and/or ornithine as precursors; other possibilities are discussed.In assays of ornithine decarboxylase, an interference of decarboxylation not due to this enzyme was observed in extracts from all species. In arginine decarboxylase assays, the interfering decarboxylation as well as the interference of arginase were apparent in two species. Addition of aminoguanidine was needed to suppress oxidative degradation of putrescine and agmatine during incubation of extracts from pea, bean, lettuce, Heliotropium angiospermum, and Heliotropium indicum.

  12. Backbone Brackets and Arginine Tweezers delineate Class I and Class II aminoacyl tRNA synthetases

    Science.gov (United States)

    Haupt, V. Joachim; Schroeder, Michael; Labudde, Dirk

    2018-01-01

    The origin of the machinery that realizes protein biosynthesis in all organisms is still unclear. One key component of this machinery are aminoacyl tRNA synthetases (aaRS), which ligate tRNAs to amino acids while consuming ATP. Sequence analyses revealed that these enzymes can be divided into two complementary classes. Both classes differ significantly on a sequence and structural level, feature different reaction mechanisms, and occur in diverse oligomerization states. The one unifying aspect of both classes is their function of binding ATP. We identified Backbone Brackets and Arginine Tweezers as most compact ATP binding motifs characteristic for each Class. Geometric analysis shows a structural rearrangement of the Backbone Brackets upon ATP binding, indicating a general mechanism of all Class I structures. Regarding the origin of aaRS, the Rodin-Ohno hypothesis states that the peculiar nature of the two aaRS classes is the result of their primordial forms, called Protozymes, being encoded on opposite strands of the same gene. Backbone Brackets and Arginine Tweezers were traced back to the proposed Protozymes and their more efficient successors, the Urzymes. Both structural motifs can be observed as pairs of residues in contemporary structures and it seems that the time of their addition, indicated by their placement in the ancient aaRS, coincides with the evolutionary trace of Proto- and Urzymes. PMID:29659563

  13. The subcellular compartmentalization of arginine metabolizing enzymes and their role in endothelial dysfunction

    Directory of Open Access Journals (Sweden)

    Feng eChen

    2013-07-01

    Full Text Available The endothelial production of nitric oxide (NO mediates endothelium-dependent vasorelaxation and restrains vascular inflammation, smooth muscle proliferation and platelet aggregation. Impaired production of NO is a hallmark of endothelial dysfunction and promotes the development of cardiovascular disease. In endothelial cells, NO is generated by endothelial nitric oxide synthase (eNOS through the conversion of its substrate, L-arginine to L-citrulline. Reduced access to L-arginine has been proposed as a major mechanism underlying reduced eNOS activity and NO production in cardiovascular disease. The arginases (Arg1 and Arg2 metabolize L-arginine to generate L-ornithine and urea and increased expression of arginase has been proposed as a mechanism of reduced eNOS activity secondary to the depletion of L-arginine. Indeed, supplemental L-arginine and suppression of arginase activity has been shown to improve endothelium-dependent relaxation and ameliorate cardiovascular disease. However, L-arginine concentrations in endothelial cells remain sufficiently high to support NO synthesis suggesting additional mechanisms. The compartmentalization of intracellular L-arginine into poorly interchangeable pools has been proposed to allow for the local depletion of L-arginine. Indeed the subcellular location of L-arginine metabolizing enzymes plays important functional roles. In endothelial cells, eNOS is found in discrete intracellular locations and the capacity to generate NO is heavily influenced by its localtion. Arg1 and Arg2 also reside in different subcellular environments and are thought to differentially influence endothelial function. The plasma membrane solute transporter, CAT-1 and the arginine recycling enzyme, ASL, co-localize with eNOS and facilitate NO release. This review highlights the importance of the subcellular location of eNOS and arginine transporting and metabolizing enzymes to NO release and cardiovascular disease.

  14. Determination of residual stresses in objects at their additive manufacturing by layer-by-layer photopolymerization method

    Science.gov (United States)

    Bychkov, P. S.; Chentsov, A. V.; Kozintsev, V. M.; Popov, A. L.

    2018-04-01

    A calculation-experimental technique is developed for identification of the shrinkage stresses generated in objects after their additive manufacturing by layer-by-layer photopolymerization. The technique is based on the analysis of shrinkage deformations at bending occurring in a series of samples in the form of plates-stripes with identical sizes, but with different time of polymerization which is predetermined during their production on the 3D printer.

  15. Arginine de novo and nitric oxide production in disease states

    OpenAIRE

    Luiking, Yvette C.; Ten Have, Gabriella A. M.; Wolfe, Robert R.; Deutz, Nicolaas E. P.

    2012-01-01

    Arginine is derived from dietary protein intake, body protein breakdown, or endogenous de novo arginine production. The latter may be linked to the availability of citrulline, which is the immediate precursor of arginine and limiting factor for de novo arginine production. Arginine metabolism is highly compartmentalized due to the expression of the enzymes involved in arginine metabolism in various organs. A small fraction of arginine enters the NO synthase (NOS) pathway. Tetrahydrobiopterin ...

  16. Accumulation of Citrulline by Microbial Arginine Metabolism during Alcoholic Fermentation of Soy Sauce.

    Science.gov (United States)

    Fang, Fang; Zhang, Jiran; Zhou, Jingwen; Zhou, Zhaohui; Li, Tieqiao; Lu, Liling; Zeng, Weizhu; Du, Guocheng; Chen, Jian

    2018-03-07

    Citrulline, the major precursor of ethyl carbamate in soy sauce, is an intermediate catabolite of arginine produced by bacteria present in soy sauce moromi mash. Pediococcus acidilactici is responsible for the formation of citrulline during the lactic acid fermentation process of soy sauce. However, citrulline accumulation during the alcoholic fermentation process and the corresponding bacteria involved have not been identified. Salt-tolerant, arginine-utilizing bacteria were isolated from moromi mash during the alcoholic fermentation process. Under normal cultivation conditions, arginine utilization by these strains did not contribute to citrulline accumulation. However, the conversion of arginine to citrulline by these bacteria increased when cultivated during the alcoholic fermentation process. Additionally, the ethanol-enhanced solubility of free fatty acids in moromi mash stimulated the accumulation of citrulline. Staphylococcus exhibited the highest capability in the conversion of arginine to citrulline.

  17. The role of bicarbonate in platelet additive solution for apheresis platelet concentrates stored with low residual plasma.

    Science.gov (United States)

    Radwanski, Katherine; Min, Kyungyoon

    2013-03-01

    Complex platelet additive solutions (PASs) are required to store platelet (PLT) concentrates with plasma levels below 30%. Previously, apheresis PLTs stored with 5% plasma in acetate- and bicarbonate-containing PAS maintained stable pH and bicarbonate levels during 7-day storage. Due to this observation, the necessity of added bicarbonate in PAS was investigated and whether the concurrent increase in PAS pH after bicarbonate addition had any effect on PLT storage. Apheresis PLTs were stored in 5% plasma-95% high- or low-pH PAS, with or without bicarbonate (n=10 per arm). Bicarbonate PAS PLTs were paired and nonbicarbonate PAS PLTs were paired (split from same double-dose collection). PLTs were evaluated for in vitro variables on Days 1 and 7 and up to Day 14 if the Day 7 pH was higher than 6.2. PLT pH was maintained above 7.3 to Day 14 in bicarbonate PAS PLTs while pH failures below 6.2 were observed in 4 of 10 and 2 of 10 units on Day 7 in low- and high-pH nonbicarbonate PAS arms, respectively. Day 7 in vitro variables in nonbicarbonate PAS PLTs with pH values of higher than 6.2 were comparable to Day 7 variables in bicarbonate PAS PLTs. The pH of bicarbonate PAS did have a small effect on pH and bicarbonate levels in PLT units, but did not have an effect on functional variables and metabolism. Bicarbonate was not required to maintain in vitro PLT function in 5% plasma-95% PAS, but was required as a pH buffer and increased PAS pH did not significantly contribute to this effect. © 2012 American Association of Blood Banks.

  18. The Effect of Carbohydrates and Arginine on Arginine Metabolism by Excised Bean Leaves in the Dark

    Science.gov (United States)

    Stewart, Cecil R.

    1975-01-01

    The effect of carbohydrate on arginine utilization by excised bean (Phaseolus vulgaris L. var. Tendergreen) leaves in the dark was studied by adding arginine to leaves differing in carbohydrate levels, and measuring the arginine content of the leaves at intervals. In nonstarved leaves, the arginine content decreased steadily after vacuum infiltration of 10 mm arginine and was essentially completely utilized by 36 hours after infiltration. In starved leaves, the arginine content did not decrease except for a brief period of about 4 hours after infiltration. The distribution of 14C after adding 14C-arginine to starved and nonstarved leaves indicated that the presence of carbohydrates in the leaves stimulates the utilization of arginine for protein synthesis and conversion to other amino acids, organic acids, and CO2 (catabolism). Adding sucrose along with arginine to starved leaves stimulated this utilization of arginine for both protein synthesis and catabolism. This effect of sugar on catabolism is different than results of similar studies done previously with proline. Increasing the concentration of added arginine greatly increased arginine catabolism but had a relatively small effect on utilization of arginine for protein synthesis. This result is the same as similar results from adding different concentrations of proline to excised leaves. PMID:16659159

  19. Symmetric Allosteric Mechanism of Hexameric Escherichia coli Arginine Repressor Exploits Competition between L-Arginine Ligands and Resident Arginine Residues

    Czech Academy of Sciences Publication Activity Database

    Strawn, R.; Melicherčík, Milan; Green, M.; Stockner, T.; Carey, J.; Ettrich, Rüdiger

    2010-01-01

    Roč. 6, č. 6 (2010), s. 1-12 ISSN 1553-734X R&D Projects: GA MŠk(CZ) LC06010; GA ČR GAP207/10/1934 Institutional research plan: CEZ:AV0Z60870520 Keywords : molecular-dynamics simulations * free-energy calculations * structural basis * DNA-binding domain * bacillus-stearothermophilus * T4 lysozyme * proteins * hemoglobin * model * affinity Subject RIV: EH - Ecology, Behaviour Impact factor: 5.515, year: 2010

  20. L-arginine biosensors: A comprehensive review

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    Neelam Verma

    2017-12-01

    Full Text Available Arginine has been considered as the most potent nutraceutics discovered ever, due to its powerful healing property, and it's been known to scientists as the Miracle Molecule. Arginine detection in fermented food products is necessary because, high level of arginine in foods forms ethyl carbamate (EC during the fermentation process. Therefore, L-arginine detection in fermented food products is very important as a control measure for quality of fermented foods, food supplements and beverages including wine. In clinical analysis arginine detection is important due to their enormous inherent versatility in various metabolic pathways, topmost in the synthesis of Nitric oxide (NO and tumor growth. A number of methods are being used for arginine detection, but biosensors technique holds prime position due to rapid response, high sensitivity and high specificity. However, there are many problems still to be addressed, including selectivity, real time analysis and interference of urea presence in the sample. In the present review we aim to emphasize the significant role of arginine in human physiology and foods. A small attempt has been made to discuss the various techniques used for development of arginine biosensor and how these techniques affect their performance. The choice of transducers for arginine biosensor ranges from optical, pH sensing, ammonia gas sensing, ammonium ion-selective, conductometric and amperometric electrodes because ammonia is formed as a final product.

  1. Stationary phase expression of the arginine biosynthetic operon argCBH in Escherichia coli

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    Sun Yuan

    2006-02-01

    Full Text Available Abstract Background Arginine biosynthesis in Escherichia coli is elevated in response to nutrient limitation, stress or arginine restriction. Though control of the pathway in response to arginine limitation is largely modulated by the ArgR repressor, other factors may be involved in increased stationary phase and stress expression. Results In this study, we report that expression of the argCBH operon is induced in stationary phase cultures and is reduced in strains possessing a mutation in rpoS, which encodes an alternative sigma factor. Using strains carrying defined argR, and rpoS mutations, we evaluated the relative contributions of these two regulators to the expression of argH using operon-lacZ fusions. While ArgR was the main factor responsible for modulating expression of argCBH, RpoS was also required for full expression of this biosynthetic operon at low arginine concentrations (below 60 μM L-arginine, a level at which growth of an arginine auxotroph was limited by arginine. When the argCBH operon was fully de-repressed (arginine limited, levels of expression were only one third of those observed in ΔargR mutants, indicating that the argCBH operon is partially repressed by ArgR even in the absence of arginine. In addition, argCBH expression was 30-fold higher in ΔargR mutants relative to levels found in wild type, fully-repressed strains, and this expression was independent of RpoS. Conclusion The results of this study indicate that both derepression and positive control by RpoS are required for full control of arginine biosynthesis in stationary phase cultures of E. coli.

  2. Qualidade da silagem de resíduo de manga com diferentes aditivos Quality of mango residue silage with different additives

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    Cristovão Colombo de Carvalho Couto Filho

    2007-10-01

    Full Text Available Com o objetivo de avaliar a qualidade da silagem de resíduo de manga (Mangifera indica L. em mistura com diferentes aditivos, em níveis crescentes de adição, foi conduzido este estudo. O delineamento experimental utilizado foi o inteiramente casualizado, com três repetições, sendo os tratamentos dispostos em um esquema fatorial do tipo (4 x 3 + 1, sendo quatro aditivos (milho desintegrado com palha e sabugo (MDPS, palha de feijão (PF, sabugo de milho (SM e casca de café (CC em três níveis de adição (10, 20 e 30% e um tratamento testemunha (resíduo de manga puro ensilado. O material experimental foi ensilado em silos de PVC adaptados com válvula tipo "Bunsen" com capacidade para aproximadamente 3 kg cada. Todos os aditivos utilizados elevaram os teores de MS. À medida que se aumentou os níveis de adição dos aditivos, houve uma redução nos valores de poder tampão (PT. Os valores de pH e nitrogênio amoniacal (N-NH3 /%N total mantiveram-se dentro dos padrões indicativos de um bom processo fermentativo. O padrão de fermentação das silagens aditivadas foi satisfatório, sem haver comprometimento na qualidade destas. Os aditivos milho desintegrado com palha e sabugo, palha de feijão ou casca de café podem ser adicionados ao processo de ensilagem do resíduo de manga nos níveis de adição de 20 ou 30%, melhorando seu padrão fermentativo.With the objective to evaluate the quality of mango (Mangifera indica L. residue silage in mixture with different additives at growing levels of addition, this study was undertaken. The experimental design utilized was the completely randomized, with three replicates. The treatments were arranged in a factorial scheme (4 x 3 + 1 type and the additives being four (ground ears with husks (GEWH, bean straw (BS, corn cob (CC and coffee hull (CH at three levels of addition (10, 20 and 30% and a control treatment (ensiled unmixed mango residue. The experimental material was ensiled in PVC silos

  3. Serum Stabilities of Short Tryptophan-and Arginine-Rich Antimicrobial Peptide Analogs

    NARCIS (Netherlands)

    Nguyen, L.T.; Chau, J.K.; Perry, N.A.; de Boer, L.; Zaat, S.A.J.; Vogel, H.J.

    2010-01-01

    Background: Several short antimicrobial peptides that are rich in tryptophan and arginine residues were designed with a series of simple modifications such as end capping and cyclization. The two sets of hexapeptides are based on the Trp- and Arg-rich primary sequences from the "antimicrobial

  4. Gas-phase salt bridge interactions between glutamic acid and arginine

    NARCIS (Netherlands)

    Jaeqx, S.; Oomens, J.; Rijs, A.M.

    2013-01-01

    The gas-phase side chain-side chain (SC-SC) interaction and possible proton transfer between glutamic acid (Glu) and arginine (Arg) residues are studied under low-temperature conditions in an overall neutral peptide. Conformation-specific IR spectra, obtained with the free electron laser FELIX, in

  5. Residual Effect Of Organic Fertilizer And Addition Inorganik Fertilizer To Nutrient Uptake Growth And Productions Of Black Soy Bean Glycine Max L. Merr At Rainfed Areas.

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    Elli Afrida

    2015-02-01

    Full Text Available Abstract Research that have theme Residual Effect of Organic Fertilizer and Addition Anorganik Fertilizer to Nutrient Uptake Growth and pruductions of Black Soy Bean Glycine max L. Merr at Rainfed Wetland. Research was conducted at Suka Makmur village sub-distric Binjai Distric Langkat. Research was arranged in split plot design main plot is applications of phonska fertilizerwith 4 level i.e 0 t ha-1 A0 0.20 t ha-1 A1 0.25 t ha-1 A2 dan 0.30 t ha-1 A3 and sub plot is residual effect from first research with 16 combinations. Research was replicated 3 times. Result of research was showed application organic fertilizer that was combinated with anorganic fertilizer can increased N and K uptake. Application organic and anorganic fertilizer as single factor showed significantly effect of number of pods and soy bean productions but at interaction treatment not significantly effect however generally occurs increased production at O33A3 tratment until 80 comparison with control.

  6. Frações fibrosas da silagem de resíduo de manga com aditivos Fibrous fractions of mango residue silage with additives

    Directory of Open Access Journals (Sweden)

    Cristovão Colombo de Carvalho Couto Filho

    2010-06-01

    Full Text Available Com o objetivo de avaliar as diferentes frações fibrosas da silagem de resíduo de manga em mistura com diferentes aditivos, em níveis crescentes de adição, foi conduzido este estudo. O delineamento experimental utilizado foi o inteiramente casualizado, com três repetições, sendo os tratamentos dispostos em um esquema fatorial do tipo (4 x 3 + 1, sendo quatro aditivos (milho desintegrado com palha e sabugo (MDPS, palha de feijão (PF, sabugo de milho (SM e casca de café (CC em três níveis de adição (10, 20 e 30% e um tratamento testemunha (resíduo de manga puro ensilado. O material experimental foi ensilado em silos de PVC adaptados com válvula tipo "Bunsen" com capacidade para aproximadamente 3 kg cada. Todos os aditivos utilizados elevaram os teores de MS. Os aditivos PF, SM e CC elevaram os teores de FDN, FDA e celulose. Quanto aos teores de hemicelulose, apenas o aditivo SM promoveu aumento com a elevação dos níveis de adição. Comportamento semelhante foi observado para o aditivo PF em relação à lignina. Os valores registrados para as diferentes frações fibrosas das silagens, quando se utilizou o MDPS, sofreram reduções em relação ao resíduo de manga ensilado puro, não diferindo, no entanto, com o aumento dos níveis de adição. De maneira geral, a utilização dos demais aditivos, promoveu elevações nos teores das variáveis estudadas.This study was undertaken with the goal of evaluating the different fibrous fractions of mango residue silage in mixture with different additives at growing levels of addition. The experimental design used was the completely randomized, with three replicates, the treatments being arranged in a 4 x 3 + 1 factorial arrangement, the additives being four (ground ears with husks (GEWH, bean straw (BS, corn cob (CC and coffee hull (CH at three levels of addition (10, 20 and 30% and a control treatment (ensiled unmixed mango residue. The experimental material was ensiled in PVC silos

  7. Supplementation with apple enriched with L-arginine may improve metabolic control and survival rate in alloxan-induced diabetic rats.

    Science.gov (United States)

    Escudero, Andrea; Petzold, Guillermo; Moreno, Jorge; Gonzalez, Marcelo; Junod, Julio; Aguayo, Claudio; Acurio, Jesenia; Escudero, Carlos

    2013-01-01

    Supplementation with L-arginine or fresh food with high content of this amino acid is associated with favorable effects in the metabolic control of diabetes. We aimed to determine whether supplementation with apples enriched with L-arginine offer additional benefits compared to L-arginine by itself in a preclinical study of diabetes. This study combines food-engineer technologies with in vivo and in vitro analysis. In vitro experiments show that cells derived from non-diabetic animals and exposed to high glucose (25 mM, 12 H) and cells isolated from alloxan-induced diabetic animals exhibited a reduction (∼50%) in the L-arginine uptake. This effect was reverted by L-arginine pretreatment (12 H) in both the normal and diabetes-derived cells. In preclinical studies, normoglycemic (n = 25) and diabetic groups (n = 50) were divided into subgroups that received either L-arginine (375 mg/kg per 10 days) or apple enriched with L-arginine or vehicle (control). In a preliminary analysis, supplementation with L-arginine by itself (50%) or apple enriched with L-arginine (100%) improve survival rate in the diabetic group compared to control (0%) at the end of the follow up (17 days). This phenomenon was associated with a partial but sustained high plasma level of L-arginine, as well as plasma concentration of nitrites and insulin in the L-arginine or apple + L-arginine groups after supplementation. Apple + L-arginine supplementation in diabetic animals induced the highest and longest effects in the level of these three markers among the studied groups. Therefore, apple enriched by L-arginine offers more benefits than L-arginine by itself in this preclinical study. Copyright © 2013 International Union of Biochemistry and Molecular Biology, Inc.

  8. DIVERSE POTENTIAL AND PHARMACOLOGICAL STUDIES OF ARGININE

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    Anju Meshram

    2015-09-01

    Full Text Available Arginine is metabolically flexible amino acid with major role in protein synthesis and detoxification of ammonia. It is involved in several metabolic pathways for the production of biologically active compounds such as creatine, nitric oxide, ornithine, glutamate, agmatine, citrulline and polyamines. Regarding this all, we review the crucial role of arginine in metabolism, diversified prospective uses and pharmacological applications. Arginine plays an important role in the treatment of tumorigenesis, asthama, gastric, erectile dysfunction, apoptosis, melanoma and congestive heart failure. Ability to produce nitric oxide offers various applications as in the prevention of age and hair loss. It serves as a precursor of creatine with ergogenic potential. The ability to increase endogenous growth hormone makes arginine a preferred supplement for the improvement of physical performance. In the present study details about the pharmacological applications of arginine based on modern scientific investigations have been discussed. There are immense properties hidden in arginine that need to be explored using the scientific investigations to make it beneficial for the medicine and human health. More research is needed to evaluate the role of arginine supplementation on exercise performance and training adaptations in healthy and diseased populations before taking any conclusions.

  9. PRMT5: A novel regulator of Hepatitis B virus replication and an arginine methylase of HBV core.

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    Barbora Lubyova

    Full Text Available In mammals, protein arginine methyltransferase 5, PRMT5, is the main type II enzyme responsible for the majority of symmetric dimethylarginine formation in polypeptides. Recent study reported that PRMT5 restricts Hepatitis B virus (HBV replication through epigenetic repression of HBV DNA transcription and interference with encapsidation of pregenomic RNA. Here we demonstrate that PRMT5 interacts with the HBV core (HBc protein and dimethylates arginine residues within the arginine-rich domain (ARD of the carboxyl-terminus. ARD consists of four arginine rich subdomains, ARDI, ARDII, ARDIII and ARDIV. Mutation analysis of ARDs revealed that arginine methylation of HBc required the wild-type status of both ARDI and ARDII. Mass spectrometry analysis of HBc identified multiple potential ubiquitination, methylation and phosphorylation sites, out of which lysine K7 and arginines R150 (within ARDI and R156 (outside ARDs were shown to be modified by ubiquitination and methylation, respectively. The HBc symmetric dimethylation appeared to be linked to serine phosphorylation and nuclear import of HBc protein. Conversely, the monomethylated HBc retained in the cytoplasm. Thus, overexpression of PRMT5 led to increased nuclear accumulation of HBc, and vice versa, down-regulation of PRMT5 resulted in reduced levels of HBc in nuclei of transfected cells. In summary, we identified PRMT5 as a potent controller of HBc cell trafficking and function and described two novel types of HBc post-translational modifications (PTMs, arginine methylation and ubiquitination.

  10. Indian women of childbearing age do not metabolically conserve arginine as do American and Jamaican women.

    Science.gov (United States)

    Kao, Christina C; Hsu, Jean W; Dwarkanath, Pratibha; Karnes, Jeffrey M; Baker, Tameka M; Bohren, Kurt M; Badaloo, Asha; Thame, Minerva M; Kurpad, Anura V; Jahoor, Farook

    2015-05-01

    In a previous study in pregnant American women, we reported that arginine flux and nitric oxide synthesis increased in trimester 2. More recently, we reported that Indian women do not increase arginine flux during pregnancy as their American or Jamaican counterparts do. The purpose of this study was to determine whether Indian women of childbearing age are producing less arginine and/or catabolizing more arginine and therefore have less available for anabolic pathways than do Jamaican and American women. Thirty healthy women aged 28.3 ± 0.8 y from the United States, India, and Jamaica (n = 10/group) were given 6 h primed, constant intravenous infusions of guanidino-¹⁵N₂-arginine, 5,5-²H₂-citrulline, ¹⁵N₂-ornithine, and ring-²H₅-phenylalanine, in addition to primed, oral doses of U-¹³C₆-arginine in both the fasting and postprandial states. An oral dose of deuterium oxide was also given to determine fat-free mass (FFM). Compared with American women, Indian and Jamaican women had greater ornithine fluxes (μmol · kg fat FFM⁻¹ · h⁻¹) in the fasting and postprandial states (27.3 ± 2.5 vs. 39.6 ± 3.7 and 37.2 ± 2.0, respectively, P = 0.01), indicating greater arginine catabolism. However, Jamaican women had a higher endogenous arginine flux than did Indian and American women in the fasting (66.1 ± 3.1 vs. 54.2 ± 3.1 and 56.1 ± 2.1, respectively, P = 0.01) and postprandial (53.8 ± 2.2 vs. 43.7 ± 4.9 and 42.8 ± 3.1, respectively, P = 0.06) states. As a consequence, Indian women had lower arginine bioavailability (μmol · kg FFM⁻¹ · h⁻¹) in the fasting state (42.0 ± 2.6) than did American (49.9 ± 1.3, P = 0.045) and Jamaican (55.5 ± 3.5, P = 0.004) women, as well as in the postprandial state (40.7 ± 3.5 vs. 51.8 ± 1.2 and 57.5 ± 3.2, respectively, P = 0.001). Compared with American and Jamaican women, Indian women of childbearing age have a decreased arginine supply because of increased arginine catabolism without an

  11. Inversion of allosteric effect of arginine on N-acetylglutamate synthase, a molecular marker for evolution of tetrapods

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    Cabrera-Luque Juan

    2008-09-01

    Full Text Available Abstract Background The efficient conversion of ammonia, a potent neurotoxin, into non-toxic metabolites was an essential adaptation that allowed animals to move from the aquatic to terrestrial biosphere. The urea cycle converts ammonia into urea in mammals, amphibians, turtles, snails, worms and many aquatic animals and requires N-acetylglutamate (NAG, an essential allosteric activator of carbamylphosphate synthetase I (CPSI in mammals and amphibians, and carbamylphosphate synthetase III (CPSIII in fish and invertebrates. NAG-dependent CPSI and CPSIII catalyze the formation of carbamylphosphate in the first and rate limiting step of ureagenesis. NAG is produced enzymatically by N-acetylglutamate synthase (NAGS, which is also found in bacteria and plants as the first enzyme of arginine biosynthesis. Arginine is an allosteric inhibitor of microbial and plant NAGS, and allosteric activator of mammalian NAGS. Results Information from mutagenesis studies of E. coli and P. aeruginosa NAGS was combined with structural information from the related bacterial N-acetylglutamate kinases to identify four residues in mammalian NAGS that interact with arginine. Substitutions of these four residues were engineered in mouse NAGS and into the vertebrate-like N-acetylglutamate synthase-kinase (NAGS-K of Xanthomonas campestris, which is inhibited by arginine. All mutations resulted in arginine losing the ability to activate mouse NAGS, and inhibit X. campestris NAGS-K. To examine at what point in evolution inversion of arginine effect on NAGS occur, we cloned NAGS from fish and frogs and examined the arginine response of their corresponding proteins. Fish NAGS were partially inhibited by arginine and frog NAGS were activated by arginine. Conclusion Difference in arginine effect on bacterial and mammalian NAGS most likely stems from the difference in the type of conformational change triggered by arginine binding to these proteins. The change from arginine

  12. Enhanced protection against malaria by indoor residual spraying in addition to insecticide treated nets: is it dependent on transmission intensity or net usage?

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    Philippa A West

    Full Text Available Insecticide treated nets (ITNs and indoor residual spraying (IRS are effective vector control tools that protect against malaria. There is conflicting evidence regarding whether using ITNs and IRS in combination provides additional benefit over using either of these methods alone. This study investigated factors that may modify the effect of the combined use of IRS and ITNs compared to using ITNs alone on malaria infection prevalence.Secondary analysis was carried out on data from a cluster randomised trial in north-west Tanzania. 50 clusters received ITNs from a universal coverage campaign; of these 25 were randomly allocated to additionally receive two rounds of IRS in 2012. In cross-sectional household surveys children 0.5-14 years old were tested for Plasmodium falciparum infections (PfPR two, six and ten months after the first IRS round.IRS protected those sleeping under nets (OR = 0.38, 95%CI 0.26-0.57 and those who did not (OR = 0.43, 95%CI 0.29-0.63. The protective effect of IRS was not modified by community level ITN use (ITN use = 50%, OR = 0.46, 95%CI 0.28-0.74. The additional protection from IRS was similar in low (<10% PfPR, OR = 0.38, 95%CI 0.19-0.75 and high transmission areas (≥10% PfPR, OR = 0.34, 95%CI 0.18-0.67. ITN use was protective at the individual-level regardless of whether the village had been sprayed (OR = 0.83, 95%CI 0.70-0.98. Living in a sprayed village was protective regardless of whether the individual slept under an ITN last night (OR = 0.41, 95%CI 0.29-0.58.Implementing IRS in addition to ITNs was beneficial for individuals from villages with a wide range of transmission intensities and net utilisation levels. Net users received additional protection from IRS. ITNs were providing some individual protection, even in this area with high levels of pyrethroid insecticide resistance. These results demonstrate that there is a supplementary benefit of IRS even when ITNs are effective.ClinicalTrials.gov NCT01697852.

  13. Influence of Addition of Fluid Catalytic Cracking Residue (FCC and the SiO2 Concentration in Alkali-Activated Ceramic Sanitary-Ware (CSW Binders

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    Juan Cosa

    2018-03-01

    Full Text Available Production of Portland cement requires a large volume of natural raw materials and releases huge amounts of CO2 to the atmosphere. Lower environmental impact alternatives focus on alkali-activated cements. In this paper, fluid catalytic cracking residue (FCC was used to partially replace (0 wt %–50 wt % ceramic sanitaryware (CSW in alkali-activated systems. Samples were activated with NaOH and sodium silicate solutions and were cured at 65 °C for 7 days and at 20 °C for 28 and 90 days. In order to increase CSW/FCC binders’ sustainability, the influence of reducing the silica concentration (from 7.28 mol·kg−1 up to 2.91 mol·kg−1 was analyzed. The microstructure of the developed binders was investigated in pastes by X-ray diffraction, thermo tests and field emission scanning electron microscopy analyses. Compressive strength evolution was assessed in mortars. The results showed a synergetic effect of the CSW/FCC combinations so that, under the studied conditions, mechanical properties significantly improved when combining both waste materials (up to 70 MPa were achieved in the mortars containing 50 wt % FCC cured at room temperature for 90 days. Addition of FCC allowed CSW to be activated at room temperature, which significantly broadens the field of applications of alkali-activated CSW binders.

  14. Short Arginine Motifs Drive Protein Stickiness in the Escherichia coli Cytoplasm.

    Science.gov (United States)

    Kyne, Ciara; Crowley, Peter B

    2017-09-19

    Although essential to numerous biotech applications, knowledge of molecular recognition by arginine-rich motifs in live cells remains limited. 1 H, 15 N HSQC and 19 F NMR spectroscopies were used to investigate the effects of C-terminal -GR n (n = 1-5) motifs on GB1 interactions in Escherichia coli cells and cell extracts. While the "biologically inert" GB1 yields high-quality in-cell spectra, the -GR n fusions with n = 4 or 5 were undetectable. This result suggests that a tetra-arginine motif is sufficient to drive interactions between a test protein and macromolecules in the E. coli cytoplasm. The inclusion of a 12 residue flexible linker between GB1 and the -GR 5 motif did not improve detection of the "inert" domain. In contrast, all of the constructs were detectable in cell lysates and extracts, suggesting that the arginine-mediated complexes were weak. Together these data reveal the significance of weak interactions between short arginine-rich motifs and the E. coli cytoplasm and demonstrate the potential of such motifs to modify protein interactions in living cells. These interactions must be considered in the design of (in vivo) nanoscale assemblies that rely on arginine-rich sequences.

  15. Arginine depletion by arginine deiminase does not affect whole protein metabolism or muscle fractional protein synthesis rate in mice

    Science.gov (United States)

    Due to the absolute need for arginine that certain cancer cells have, arginine depletion is a therapy in clinical trials to treat several types of cancers. Arginine is an amino acids utilized not only as a precursor for other important molecules, but also for protein synthesis. Because arginine depl...

  16. Amelioration of bauxite residue sand by intermittent additions of nitrogen fertiliser and leaching fractions: The effect on growth of kikuyu grass and fate of applied nutrients.

    Science.gov (United States)

    Kaur, Navjot; Phillips, Ian; Fey, Martin V

    2016-04-15

    Bauxite residue, a waste product of aluminium processing operations is characterised by high pH, salinity and exchangeable sodium which hinders sustainable plant growth. The aim of this study was to investigate the uptake form, optimum application rate and timing of nitrogen fertiliser to improve bauxite residue characteristics for plant growth. Kikuyu grass was grown in plastic columns filled with residue sand/carbonated residue mud mixture (20:1) previously amended with gypsum, phosphoric acid and basal nutrients. The experiment was set up as a 4×4 factorial design comprising four levels of applied nitrogen (N) fertiliser (0, 3, 6 and 12mgNkg(-1) residue) and four frequencies of leaching (16, 8 and 4day intervals). We hypothesised that the use of ammonium sulfate fertiliser would increase retention of N within the rhizosphere thereby encouraging more efficient fertiliser use. We found that N uptake by kikuyu grass was enhanced due to leaching of excess salts and alkalinity from the residue profile. It was also concluded that biomass production and associated N uptake by kikuyu grass grown in residue is dependent on the type of fertiliser used. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Ecological Effect of Arginine on Oral Microbiota.

    Science.gov (United States)

    Zheng, Xin; He, Jinzhi; Wang, Lin; Zhou, Shuangshuang; Peng, Xian; Huang, Shi; Zheng, Liwei; Cheng, Lei; Hao, Yuqing; Li, Jiyao; Xu, Jian; Xu, Xin; Zhou, Xuedong

    2017-08-03

    Dental caries is closely associated with the microbial dybiosis between acidogenic/aciduric pathogens and alkali-generating commensal bacteria colonized in the oral cavity. Our recent studies have shown that arginine may represent a promising anti-caries agent by modulating microbial composition in an in vitro consortium. However, the effect of arginine on the oral microbiota has yet to be comprehensively delineated in either clinical cohort or in vitro biofilm models that better represent the microbial diversity of oral cavity. Here, by employing a clinical cohort and a saliva-derived biofilm model, we demonstrated that arginine treatment could favorably modulate the oral microbiota of caries-active individuals. Specifically, treatment with arginine-containing dentifrice normalized the oral microbiota of caries-active individuals similar to that of caries-free controls in terms of microbial structure, abundance of typical species, enzymatic activities of glycolysis and alkali-generation related enzymes and their corresponding transcripts. Moreover, we found that combinatory use of arginine with fluoride could better enrich alkali-generating Streptococcus sanguinis and suppress acidogenic/aciduric Streptococcus mutans, and thus significantly retard the demineralizing capability of saliva-derived oral biofilm. Hence, we propose that fluoride and arginine have a potential synergistic effect in maintaining an eco-friendly oral microbial equilibrium in favor of better caries management.

  18. THE ARGININE AND PREARGININE GROUPS IN EDESTIN.

    Science.gov (United States)

    Simms, H S

    1930-09-20

    The author corroborates the data of Schmidt showing that the dissociation index of the third group of arginine is pK(3)' = 12.5. New titration data of edestin have been obtained in very alkaline solutions and show that there is a corresponding group with a titration index of pG' = 12.0, but present in much less quantity than can account for the arginine found on hydrolysis. The data support the theory that the combination of strong base or strong acid with proteins is produced by the formation of salts with the "extra groups" of those trivalent amino acids which can be isolated from the protein, with the exception of arginine. Arginine contributes to the titration curve in much smaller amount than is found on hydrolysis. This deficiency in the arginine group may be accounted for by the basic group in proteins having a titration index of pG' = 3.8 to 4.6 (depending on the protein), which apparently yields arginine on hydrolysis, and may properly be called prearginine.

  19. Arginine promotes Proteus mirabilis motility and fitness by contributing to conservation of the proton gradient and proton motive force.

    Science.gov (United States)

    Armbruster, Chelsie E; Hodges, Steven A; Smith, Sara N; Alteri, Christopher J; Mobley, Harry L T

    2014-10-01

    Swarming contributes to Proteus mirabilis pathogenicity by facilitating access to the catheterized urinary tract. We previously demonstrated that 0.1-20 mmol/L arginine promotes swarming on normally nonpermissive media and that putrescine biosynthesis is required for arginine-induced swarming. We also previously determined that arginine-induced swarming is pH dependent, indicating that the external proton concentration is critical for arginine-dependent effects on swarming. In this study, we utilized survival at pH 5 and motility as surrogates for measuring changes in the proton gradient (ΔpH) and proton motive force (μH(+) ) in response to arginine. We determined that arginine primarily contributes to ΔpH (and therefore μH(+) ) through the action of arginine decarboxylase (speA), independent of the role of this enzyme in putrescine biosynthesis. In addition to being required for motility, speA also contributed to fitness during infection. In conclusion, consumption of intracellular protons via arginine decarboxylase is one mechanism used by P. mirabilis to conserve ΔpH and μH(+) for motility. © 2014 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.

  20. Heterologous radioimmunoassay for arginine vasopressin

    International Nuclear Information System (INIS)

    Shimamoto, K.; Murase, T.; Yamaji, T.

    1976-01-01

    A sensitive and specific radioimmunoassay for arginine vasopressin (AVP) was developed utilizing the antisera against lysine vasopressin (LVP) in combination with a labeled AVP. The assay employs an acetone extraction procedure and detects as little as 0.8 pg. per millimeter of AVP in human plasma. In normal subjects, the mean (+- S.D.) plasma concentration of AVP was 4.9 +- 1.2 pg. per milliliter after fluid deprivation and 1.2 +- 0.4 pg. per milliliter after water loading. Plasma AVP levels correlated significantly with plasma osmolalities. In four patients with diabetes insipidus, plasma AVP concentrations ranged from less than 0.8 to 1.2 pg. per milliliter, whereas six patients with the syndrome of inappropriate ADH secretion showed plasma levels of AVP which correspond to those of the dehydrated state in normal subjects or greater, although plasma osmolalities were low in all cases. It was concluded that the present radioimmunoassay method for AVP provides a useful way of assessing neurohypophyseal function in man

  1. Arginine- and Polyamine-Induced Lactic Acid Resistance in Neisseria gonorrhoeae.

    Directory of Open Access Journals (Sweden)

    Zheng Gong

    Full Text Available Microbe-derived lactic acid protects women from pathogens in their genital tract. The purpose of this study was to determine lactic acid susceptibility of Neisseria gonorrhoeae, and identify potential acid resistance mechanisms present in this pathogen. Tested in vitro, lactic acid killed all 10 gonococcal strains analyzed in a low pH-dependent manner. Full inactivation occurred at pH 4.5. At low pH, lactic acid treatment resulted in the entry of the DNA-binding fluorochrome propidium iodide into the microbial cells, suggesting that hydrogen ions from lactic acid compromise the integrity of the bacterial cell wall/membrane. Most likely, hydrogen ions also inactivate intracellular proteins since arginine rendered significant protection against lactic acid presumably through action of the gonococcal arginine decarboxylase, an enzyme located in the bacterial cytoplasm. Surprisingly, arginine also lessened lactic acid-mediated cell wall/membrane disruption. This effect is probably mediated by agmatine, a triamine product of arginine decarboxylase, since agmatine demonstrated a stronger protective effect on GC than arginine at equal molar concentration. In addition to agmatine, diamines cadaverine and putrescine, which are generated by bacterial vaginosis-associated microbes, also induced significant resistance to lactic acid-mediated GC killing and cell wall/membrane disruption. These findings suggest that the arginine-rich semen protects gonococci through both neutralization-dependent and independent mechanisms, whereas polyamine-induced acid resistance contributes to the increased risk of gonorrhea in women with bacterial vaginosis.

  2. The Conserved Arginine Cluster in the Insert of the Third Cytoplasmic Loop of the Long Form of the D2 Dopamine Receptor (D2L-R Acts as an Intracellular Retention Signal

    Directory of Open Access Journals (Sweden)

    Valentina Kubale

    2016-07-01

    Full Text Available This study examined whether the conserved arginine cluster present within the 29-amino acid insert of the long form of the D2 dopamine receptor (D2L-R confers its predominant intracellular localization. We hypothesized that the conserved arginine cluster (RRR located within the insert could act as an RXR-type endoplasmic reticulum (ER retention signal. Arginine residues (R within the cluster at positions 267, 268, and 269 were charge-reserved to glutamic acids (E, either individually or in clusters, thus generating single, double, and triple D2L-R mutants. Through analyses of cellular localization by confocal microscopy and enzyme-linked immunosorbent assay (ELISA, radioligand binding assay, bioluminescence resonance energy transfer (BRET2 β-arrestin 2 (βarr2 recruitment assay, and cAMP signaling, it was revealed that charge reversal of the R residues at all three positions within the motif impaired their colocalization with ER marker calnexin and led to significantly improved cell surface expression. Additionally, these data demonstrate that an R to glutamic acid (E substitution at position 2 within the RXR motif is not functionally permissible. Furthermore, all generated D2L-R mutants preserved their functional integrity regarding ligand binding, agonist-induced βarr2 recruitment and Gαi-mediated signaling. In summary, our results show that the conserved arginine cluster within the 29-amino acid insert of third cytoplasmic loop (IC3 of the D2L-R appears to be the ER retention signal.

  3. Ablation of arginase II spares arginine and abolishes the arginine requirement for growth in male mice

    Science.gov (United States)

    Arginine is considered a semi-essential amino acid in many species, including humans, because under certain conditions its demand exceeds endogenous production. Arginine availability, however, is not only determined by its production, but also by its disposal. Manipulation of disposal pathways has t...

  4. IMMUNOSUPPRESSIVE EFFECTS OF ARGININE DEIMINASE FROM STREPTOCOCCUS PYOGENES

    Directory of Open Access Journals (Sweden)

    E. A. Starikova

    2015-01-01

    Full Text Available Many pathogens use metabolic pathway of arginine for successful dissemination. Bacterial arginine deiminase hydrolyzes arginine to form one molecule of ammonia and two molecules of ATP. The activity of the enzyme contributes to the improvement of survival of pathogenic bacteria in conditions of low pH at the site of infection or in phagolysosome, as well as in anaerobic conditions, and also leads to deficiency of arginine. Metabolism of arginine plays an important role in regulating the functions of immune system cells in mammals. Arginine is a substrate of enzymes NOS and arginase. Arginine depletion, potentially contributs to immunosuppression. The review analyzed the literature data on the effect of streptococcal arginine deiminase on the metabolism of arginine eukaryotic cells, and discusses immunosuppressive action of the enzyme.

  5. The Role of Protein Arginine Methyltransferases in Inflammatory Responses

    Directory of Open Access Journals (Sweden)

    Ji Hye Kim

    2016-01-01

    Full Text Available Protein arginine methyltransferases (PRMTs mediate the methylation of a number of protein substrates of arginine residues and serve critical functions in many cellular responses, including cancer development, progression, and aggressiveness, T-lymphocyte activation, and hepatic gluconeogenesis. There are nine members of the PRMT family, which are divided into 4 types (types I–IV. Although most PRMTs do not require posttranslational modification (PTM to be activated, fine-tuning modifications, such as interactions between cofactor proteins, subcellular compartmentalization, and regulation of RNA, via micro-RNAs, seem to be required. Inflammation is an essential defense reaction of the body to eliminate harmful stimuli, including damaged cells, irritants, or pathogens. However, chronic inflammation can eventually cause several types of diseases, including some cancers, atherosclerosis, rheumatoid arthritis, and periodontitis. Therefore, inflammation responses should be well modulated. In this review, we briefly discuss the role of PRMTs in the control of inflammation. More specifically, we review the roles of four PRMTs (CARM1, PRMT1, PRMT5, and PRMT6 in modulating inflammation responses, particularly in terms of modulating the transcriptional factors or cofactors related to inflammation. Based on the regulatory roles known so far, we propose that PRMTs should be considered one of the target molecule groups that modulate inflammatory responses.

  6. A Heparin Binding Motif Rich in Arginine and Lysine is the Functional Domain of YKL-40

    Directory of Open Access Journals (Sweden)

    Nipaporn Ngernyuang

    2018-02-01

    Full Text Available The heparin-binding glycoprotein YKL-40 (CHI3L1 is intimately associated with microvascularization in multiple human diseases including cancer and inflammation. However, the heparin-binding domain(s pertinent to the angiogenic activity have yet been identified. YKL-40 harbors a consensus heparin-binding motif that consists of positively charged arginine (R and lysine (K (RRDK; residues 144–147; but they don't bind to heparin. Intriguingly, we identified a separate KR-rich domain (residues 334–345 that does display strong heparin binding affinity. A short synthetic peptide spanning this KR-rich domain successfully competed with YKL-40 and blocked its ability to bind heparin. Three individual point mutations, where alanine (A substituted for K or R (K337A, K342A, R344A, led to remarkable decreases in heparin-binding ability and angiogenic activity. In addition, a neutralizing anti-YKL-40 antibody that targets these residues and prevents heparin binding impeded angiogenesis in vitro. MDA-MB-231 breast cancer cells engineered to express ectopic K337A, K342A or R344A mutants displayed reduced tumor development and compromised tumor vessel formation in mice relative to control cells expressing wild-type YKL-40. These data reveal that the KR-rich heparin-binding motif is the functional heparin-binding domain of YKL-40. Our findings shed light on novel molecular mechanisms underlying endothelial cell angiogenesis promoted by YKL-40 in a variety of diseases.

  7. Improving the thermostability by introduction of arginines on the surface of α-L-rhamnosidase (r-Rha1) from Aspergillus niger.

    Science.gov (United States)

    Li, Lijun; Liao, Hui; Yang, Yan; Gong, Jianye; Liu, Jianan; Jiang, Zedong; Zhu, Yanbing; Xiao, Anfeng; Ni, Hui

    2018-06-01

    To improve the thermostability of α-L-rhamnosidase (r-Rha1), an enzyme previously identified from Aspergillus niger JMU-TS528, multiple arginine (Arg) residues were introduced into the r-Rha1 sequence to replace several lysine (Lys) residues that located on the surface of the folded r-Rha1. Hinted by in silico analysis, five surface Lys residues (K134, K228, K406, K440, K573) were targeted to produce a list of 5 single-residue mutants and 4 multiple-residue mutants using site-directed mutagenesis. Among these mutants, a double Lys to Arg mutant, i.e. K406R/K573R, showed the best thermostability improvement. The half-life of this mutant's enzyme activity increased 3 h at 60 °C, 23 min at 65 °C, and 3.5 min at 70 °C, when compared with the wild type. The simulated protein structure based interaction analysis and molecular dynamics calculation indicate that the thermostability improvement of the mutant K406R-K573R was possibly due to the extra hydrogen bonds, the additional cation-π interactions, and the relatively compact conformation. With the enhanced thermostability, the α-L-rhamnosidase mutant, K406R-K573R, has potentially broadened the r-Rha1 applications in food processing industry. Copyright © 2018 Elsevier B.V. All rights reserved.

  8. Impaired nitric oxide production in children with MELAS syndrome and the effect of arginine and citrulline supplementation.

    Science.gov (United States)

    El-Hattab, Ayman W; Emrick, Lisa T; Hsu, Jean W; Chanprasert, Sirisak; Almannai, Mohammed; Craigen, William J; Jahoor, Farook; Scaglia, Fernando

    2016-04-01

    Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome is one of the most frequent maternally inherited mitochondrial disorders. The pathogenesis of this syndrome is not fully understood and believed to result from several interacting mechanisms including impaired mitochondrial energy production, microvasculature angiopathy, and nitric oxide (NO) deficiency. NO deficiency in MELAS syndrome is likely to be multifactorial in origin with the decreased availability of the NO precursors, arginine and citrulline, playing a major role. In this study we used stable isotope infusion techniques to assess NO production in children with MELAS syndrome and healthy pediatric controls. We also assessed the effect of oral arginine and citrulline supplementations on NO production in children with MELAS syndrome. When compared to control subjects, children with MELAS syndrome were found to have lower NO production, arginine flux, plasma arginine, and citrulline flux. In children with MELAS syndrome, arginine supplementation resulted in increased NO production, arginine flux, and arginine concentration. Citrulline supplementation resulted in a greater increase of these parameters. Additionally, citrulline supplementation was associated with a robust increase in citrulline concentration and flux and de novo arginine synthesis rate. The greater effect of citrulline in increasing NO production is due to its greater ability to increase arginine availability particularly in the intracellular compartment in which NO synthesis takes place. This study, which is the first one to assess NO metabolism in children with mitochondrial diseases, adds more evidence to the notion that NO deficiency occurs in MELAS syndrome, suggests a better effect for citrulline because of its greater role as NO precursor, and indicates that impaired NO production occurs in children as well as adults with MELAS syndrome. Thus, the initiation of treatment with NO precursors may be

  9. Mutation of exposed hydrophobic amino acids to arginine to increase protein stability

    OpenAIRE

    Strub, Caroline; Alies, Carole; Lougarre, Andrée; Ladurantie, Caroline; Czaplicki, Jerzy; Fournier, Didier

    2004-01-01

    Abstract Background One strategy to increase the stability of proteins is to reduce the area of water-accessible hydrophobic surface. Results In order to test it, we replaced 14 solvent-exposed hydrophobic residues of acetylcholinesterase by arginine. The stabilities of the resulting proteins were tested using denaturation by high temperature, organic solvents, urea and by proteolytic digestion. Conclusion Altough the mutational effects were rather small, this strategy proved to be successful...

  10. Calcium Sensing Receptor Mutations Implicated in Pancreatitis and Idiopathic Epilepsy Syndrome Disrupt an Arginine-rich Retention Motif

    Science.gov (United States)

    Stepanchick, Ann; McKenna, Jennifer; McGovern, Olivia; Huang, Ying; Breitwieser, Gerda E.

    2010-01-01

    Calcium sensing receptor (CaSR) mutations implicated in familial hypocalciuric hypercalcemia, pancreatitis and idiopathic epilepsy syndrome map to an extended arginine-rich region in the proximal carboxyl terminus. Arginine-rich motifs mediate endoplasmic reticulum retention and/or retrieval of multisubunit proteins so we asked whether these mutations, R886P, R896H or R898Q, altered CaSR targeting to the plasma membrane. Targeting was enhanced by all three mutations, and Ca2+-stimulated ERK1/2 phosphorylation was increased for R896H and R898Q. To define the role of the extended arginine-rich region in CaSR trafficking, we independently determined the contributions of R890/R891 and/or R896/K897/R898 motifs by mutation to alanine. Disruption of the motif(s) significantly increased surface expression and function relative to wt CaSR. The arginine-rich region is flanked by phosphorylation sites at S892 (protein kinase C) and S899 (protein kinase A). The phosphorylation state of S899 regulated recognition of the arginine-rich region; S899D showed increased surface localization. CaSR assembles in the endoplasmic reticulum as a covalent disulfide-linked dimer and we determined whether retention requires the presence of arginine-rich regions in both subunits. A single arginine-rich region within the dimer was sufficient to confer intracellular retention comparable to wt CaSR. We have identified an extended arginine-rich region in the proximal carboxyl terminus of CaSR (residues R890 - R898) which fosters intracellular retention of CaSR and is regulated by phosphorylation. Mutation(s) identified in chronic pancreatitis and idiopathic epilepsy syndrome therefore increase plasma membrane targeting of CaSR, likely contributing to the altered Ca2+ signaling characteristic of these diseases. PMID:20798521

  11. Tuning interionic interaction by rationally controlling solution pH for highly selective colorimetric sensing of arginine.

    Science.gov (United States)

    Qian, Qin; Hao, Jie; Ma, Wenjie; Yu, Ping; Mao, Lanqun

    2016-04-01

    Direct selective sensing of arginine in central nervous systems remains very essential to understanding of the molecular basis of some physiological events. This study presents the first demonstration on a simple yet effective method for arginine sensing with gold nanoparticles (Au-NPs) as the signal readout. The rationale for the method is based on the pH-dependent feature of the interionic interaction between cysteine and arginine. At pH 6.0, cysteine can only interact with arginine through the ion-pair interaction and such interaction can lead to the changes in both the solution color and UV-vis spectrum of the cysteine-protected Au-NPs upon the addition of arginine. These changes are further developed into an analytical strategy for effective sensing of arginine by rationally controlling the pH values of Au-NP dispersions with the ratio of the absorbance at 650 nm (A 650) to that at 520 nm (A 520) (A 650/A 520) as a parameter for analysis. The method is responsive to arginine without the interference from other species in the cerebral system; under the optimized conditions, the A 650/A 520 values are linear with the concentration of arginine within a concentration range from 0.80 to 64 μM, yet remain unchanged with the addition of other kinds of amino acids or the species in the central nervous system into the Au-NPs dispersion containing cysteine. The method demonstrated here is reliable and robust and could thus be used for detection of the increase of arginine in central nervous systems.

  12. Powder addition assessment of manganese residue ceramic matrix coating; Avaliacao da adicao do po de residuo de manganes em matriz ceramica para revestimento

    Energy Technology Data Exchange (ETDEWEB)

    Conceicao, A.C.R. da; Santos, O.C.; Leao, M.A., E-mail: arangel-ma@hotmail.com [Instituto Federal de Educacao, Ciencia e Tecnologia da Bahia (IFBA), BA (Brazil)

    2016-07-01

    The use of recycled materials in the composition of new products follows the production's worldwide trending, meeting new technological requirements and environmental concerns. This work aims to utilize the residue of manganese dust on ceramic mass for the production of ceramic coating. The raw materials were characterized by both x-ray fluorescence and diffraction. The powder residue added to clay in the percentage of 0%, 5%, 10% and 15% (measured in weight) was compressed by a uniaxial pressing of 30MPa and the sintering temperatures were 900°, 1000° and 1100°. The samples were analysed in relation to flexural strength, bulk density, water absorption and linear shrinkage. The microstructural variation was also analysed by x-ray diffraction and electron microscopy. The results showed that there is a viability for the production of porcelain ceramic coating (A3 and A4 formulations) and stoneware (A2 formulation) according to the specification of technical standards. author)

  13. The do's and don'ts of arginine supplementation

    African Journals Online (AJOL)

    to meet the body's nutritional needs for energy, protein and micronutrients. ... inflammatory response syndrome (SIRS) and therefore the use of arginine in this ... smooth muscle cell proliferation12 and controlling vascular oxidative stress and the ... reduced arginine levels in sepsis that reflect the specific changes in arginine ...

  14. Unique contributions of an arginine side chain to ligand recognition in a glutamate-gated chloride channel

    DEFF Research Database (Denmark)

    Lynagh, Timothy; Komnatnyy, Vitaly V; Pless, Stephan A

    2017-01-01

    Glutamate recognition by neurotransmitter receptors often relies on arginine (Arg) residues in the binding site, leading to the assumption that charge-charge interactions underlie ligand recognition. However, assessing the precise chemical contribution of Arg side chains to protein function......-gated chloride channel from the nematode Haemonchus contortus. Our data unveil a surprisingly small contribution of charge at a conserved arginine side chain previously suggested to form a salt bridge with the ligand, glutamate. Instead, our data show that Arg contributes crucially to ligand sensitivity via...

  15. Low plasma arginine:asymmetric dimethyl arginine ratios predict mortality after intracranial aneurysm rupture

    DEFF Research Database (Denmark)

    Staalsø, Jonatan Myrup; Bergström, Anita; Edsen, Troels

    2013-01-01

    Asymmetrical dimethylarginine (ADMA), an endogenous inhibitor of nitric oxide synthases, predicts mortality in cardiovascular disease and has been linked to cerebral vasospasm after aneurysmal subarachnoid hemorrhage (SAH). In this prospective study, we assessed whether circulating ADMA, arginine...

  16. Risk-based approach to developing a national residue sampling plan for testing under European Union regulation for veterinary medicinal products and coccidiostat feed additives in domestic animal production.

    Science.gov (United States)

    Danaher, Martin; Shanahan, Conor; Butler, Francis; Evans, Rhodri; O'Sullivan, Dan; Glynn, Denise; Camon, Tim; Lawlor, Peadar; O'Keeffe, Michael

    2016-07-01

    A ranking system for veterinary medicinal products and coccidiostat feed additives has been developed as a tool to be applied in a risk-based approach to the residue testing programme for foods of animal origin in the Irish National Residue Control Plan (NRCP). Three characteristics of substances that may occur as residues in food are included in the developed risk ranking system: Potency, as measured by the acceptable daily intake assigned by the European Medicines Agency Committee for Medicinal Products for Veterinary Use, to each substance; Usage, as measured by the three factors of Number of Doses, use on Individual animals or for Group treatment, and Withdrawal Period; and Residue Occurrence, as measured by the number of Non-Compliant Samples in the NRCP. For both Number of Doses and Non-Compliant Samples, data for the 5-year period 2008-12 have been used. The risk ranking system for substances was developed for beef cattle, sheep and goats, pigs, chickens and dairy cattle using a scoring system applied to the various parameters described above to give an overall score based on the following equation: Potency × Usage (Number of Doses + Individual/Group Use + Withdrawal Period) × Residue Occurrence. Applying this risk ranking system, the following substances are ranked very highly: antimicrobials such as amoxicillin (for all species except pigs), marbofloxacillin (for beef cattle), oxytetracycline (for all species except chickens), sulfadiazine with trimethoprim (for pigs and chickens) and tilmicosin (for chickens); antiparasitic drugs, such as the benzimidazoles triclabendazole (for beef and dairy cattle), fenbendazole/oxfendazole (for sheep/goats and dairy cattle) and albendazole (for dairy cattle), the avermectin ivermectin (for beef cattle), and anti-fluke drugs closantel and rafoxanide (for sheep/goats); the anticoccidials monensin, narasin, nicarbazin and toltrazuril (for chickens). The risk ranking system described is a relatively simple system

  17. Modulators of arginine metabolism support cancer immunosurveillance

    Directory of Open Access Journals (Sweden)

    Freschi Massimo

    2009-01-01

    Full Text Available Abstract Background Tumor-associated accrual of myeloid derived suppressor cells (MDSC in the blood, lymphoid organs and tumor tissues may lead to perturbation of the arginine metabolism and impairment of the endogenous antitumor immunity. The objective of this study was to evaluate whether accumulation of MDSC occurred in Th2 prone BALB/c and Th1 biased C57BL/6 mice bearing the C26GM colon carcinoma and RMA T lymphoma, respectively, and to investigate whether N(G nitro-L-arginine methyl ester (L-NAME and sildenafil, both modulators of the arginine metabolism, restored antitumor immunity. Results We report here that MDSC accumulate in the spleen and blood of mice irrespective of the mouse and tumor model used. Treatment of tumor-bearing mice with either the phosphodiesterase-5 inhibitor sildenafil or the nitric-oxide synthase (NOS inhibitor L-NAME significantly restrained tumor growth and expanded the tumor-specific immune response. Conclusion Our data emphasize the role of MDSC in modulating the endogenous tumor-specific immune response and underline the anti-neoplastic therapeutic potential of arginine metabolism modulators.

  18. Altered brain arginine metabolism in schizophrenia.

    Science.gov (United States)

    Liu, P; Jing, Y; Collie, N D; Dean, B; Bilkey, D K; Zhang, H

    2016-08-16

    Previous research implicates altered metabolism of l-arginine, a versatile amino acid with a number of bioactive metabolites, in the pathogenesis of schizophrenia. The present study, for we believe the first time, systematically compared the metabolic profile of l-arginine in the frontal cortex (Brodmann's area 8) obtained post-mortem from schizophrenic individuals and age- and gender-matched non-psychiatric controls (n=20 per group). The enzyme assays revealed no change in total nitric oxide synthase (NOS) activity, but significantly increased arginase activity in the schizophrenia group. Western blot showed reduced endothelial NOS protein expression and increased arginase II protein level in the disease group. High-performance liquid chromatography and liquid chromatography/mass spectrometric assays confirmed significantly reduced levels of γ-aminobutyric acid (GABA), but increased agmatine concentration and glutamate/GABA ratio in the schizophrenia cases. Regression analysis indicated positive correlations between arginase activity and the age of disease onset and between l-ornithine level and the duration of illness. Moreover, cluster analyses revealed that l-arginine and its main metabolites l-citrulline, l-ornithine and agmatine formed distinct groups, which were altered in the schizophrenia group. The present study provides further evidence of altered brain arginine metabolism in schizophrenia, which enhances our understanding of the pathogenesis of schizophrenia and may lead to the future development of novel preventions and/or therapeutics for the disease.

  19. Activities of Arginine and Ornithine Decarboxylases in Various Plant Species 1

    Science.gov (United States)

    Birecka, Helena; Bitonti, Alan J.; McCann, Peter P.

    1985-01-01

    In extracts from the youngest leaves of Avena sativa, Hordeum vulgare, Zea Mays, Pisum sativum, Phaseolus vulgaris, Lactuca sativa, and four pyrrolizidine alkaloid-bearing species of Heliotropium, the activities of ornithine decarboxylase, close to Vmax, ranged between traces and 1.5 nanomoles per hour per gram fresh weight when based on putrescine formed during incubation with labeled ornithine. The arginine decarboxylase activities in the same extracts ranged between 8 and 8000 nanomoles per hour per gram fresh weight being lowest in the borages and highest in oat and barley. α-Difluoromethylornithine and α-difluoromethylarginine inhibited ornithine and arginine decarboxylases, respectively, in all species. Agmatine, putrescine, spermidine, and spermine were found in all, diaminopropane in eight, and cadaverine in three species. No correlation was observed between arginine or ornithine decarboxylase level and the levels of total polyamines. The in vitro decarboxylase activities found in the borages cannot explain the high accumulation of putrescine-derived pyrrolizidines in their youngest leaves if the pyrrolizidines are produced in situ from arginine and/or ornithine as precursors; other possibilities are discussed. In assays of ornithine decarboxylase, an interference of decarboxylation not due to this enzyme was observed in extracts from all species. In arginine decarboxylase assays, the interfering decarboxylation as well as the interference of arginase were apparent in two species. Addition of aminoguanidine was needed to suppress oxidative degradation of putrescine and agmatine during incubation of extracts from pea, bean, lettuce, Heliotropium angiospermum, and Heliotropium indicum. PMID:16664442

  20. Apple snack enriched with L-arginine using vacuum impregnation/ohmic heating technology.

    Science.gov (United States)

    Moreno, Jorge; Echeverria, Julian; Silva, Andrea; Escudero, Andrea; Petzold, Guillermo; Mella, Karla; Escudero, Carlos

    2017-07-01

    Modern life has created a high demand for functional food, and in this context, emerging technologies such as vacuum impregnation and ohmic heating have been applied to generate functional foods. The aim of this research was to enrich the content of the semi-essential amino acid L-arginine in apple cubes using vacuum impregnation, conventional heating, and ohmic heating. Additionally, combined vacuum impregnation/conventional heating and vacuum impregnation/ohmic heating treatments were evaluated. The above treatments were applied at 30, 40 and 50  ℃ and combined with air-drying at 40 ℃ in order to obtain an apple snack rich in L-arginine. Both the impregnation kinetics of L-arginine and sample color were evaluated. The impregnated samples created using vacuum impregnation/ohmic heating at 50 ℃ presented a high content of L-arginine, an effect attributed primarily to electropermeabilization. Overall, vacuum impregnation/ohmic heating treatment at 50 ℃, followed by drying at 40 ℃, was the best process for obtaining an apple snack rich in L-arginine.

  1. l-Arginine-Dependent Epigenetic Regulation of Interleukin-10, but Not Transforming Growth Factor-β, Production by Neonatal Regulatory T Lymphocytes

    Science.gov (United States)

    Yu, Hong-Ren; Tsai, Ching-Chang; Chang, Ling-Sai; Huang, Hsin-Chun; Cheng, Hsin-Hsin; Wang, Jiu-Yao; Sheen, Jiunn-Ming; Kuo, Ho-Chang; Hsieh, Kai-Sheng; Huang, Ying-Hsien; Yang, Kuender D.; Hsu, Te-Yao

    2017-01-01

    A growing number of diseases in humans, including trauma, certain cancers, and infection, are known to be associated with l-arginine deficiency. In addition, l-arginine must be supplemented by diet during pregnancy to aid fetal development. In conditions of l-arginine depletion, T cell proliferation is impaired. We have previously shown that neonatal blood has lower l-arginine levels than adult blood, which is associated with poor neonatal lymphocyte proliferation, and that l-arginine enhances neonatal lymphocyte proliferation through an interleukin (IL)-2-independent pathway. In this study, we have further investigated how exogenous l-arginine enhances neonatal regulatory T-cells (Tregs) function in relation to IL-10 production under epigenetic regulation. Results showed that cord blood mononuclear cells (CBMCs) produced higher levels of IL-10 than adult peripheral blood mononuclear cells (PBMCs) by phytohemagglutinin stimulation but not by anti-CD3/anti-CD28 stimulation. Addition of exogenous l-arginine had no effect on transforming growth factor-β production by PBMCs or CBMCs, but enhanced IL-10 production by neonatal CD4+CD25+FoxP3+ Tregs. Further studies showed that IL-10 promoter DNA hypomethylation, rather than histone modification, corresponded to the l-arginine-induced increase in IL-10 production by neonatal CD4+ T cells. These results suggest that l-arginine modulates neonatal Tregs through the regulation of IL-10 promoter DNA methylation. l-arginine supplementation may correct the Treg function in newborns with l-arginine deficiency. PMID:28487700

  2. l-Arginine-Dependent Epigenetic Regulation of Interleukin-10, but Not Transforming Growth Factor-β, Production by Neonatal Regulatory T Lymphocytes

    Directory of Open Access Journals (Sweden)

    Kuender D. Yang

    2017-04-01

    Full Text Available A growing number of diseases in humans, including trauma, certain cancers, and infection, are known to be associated with l-arginine deficiency. In addition, l-arginine must be supplemented by diet during pregnancy to aid fetal development. In conditions of l-arginine depletion, T cell proliferation is impaired. We have previously shown that neonatal blood has lower l-arginine levels than adult blood, which is associated with poor neonatal lymphocyte proliferation, and that l-arginine enhances neonatal lymphocyte proliferation through an interleukin (IL-2-independent pathway. In this study, we have further investigated how exogenous l-arginine enhances neonatal regulatory T-cells (Tregs function in relation to IL-10 production under epigenetic regulation. Results showed that cord blood mononuclear cells (CBMCs produced higher levels of IL-10 than adult peripheral blood mononuclear cells (PBMCs by phytohemagglutinin stimulation but not by anti-CD3/anti-CD28 stimulation. Addition of exogenous l-arginine had no effect on transforming growth factor-β production by PBMCs or CBMCs, but enhanced IL-10 production by neonatal CD4+CD25+FoxP3+ Tregs. Further studies showed that IL-10 promoter DNA hypomethylation, rather than histone modification, corresponded to the l-arginine-induced increase in IL-10 production by neonatal CD4+ T cells. These results suggest that l-arginine modulates neonatal Tregs through the regulation of IL-10 promoter DNA methylation. l-arginine supplementation may correct the Treg function in newborns with l-arginine deficiency.

  3. The control of fruiting body formation in the ascomycete Sordaria macrospora Auersw. by arginine and biotin: a two-factor analysis.

    Science.gov (United States)

    Molowitz, R; Bahn, M; Hock, B

    1976-01-01

    Fruiting body formation of Sordaria macrospora Auersw. is controlled by L-arginine and biotin when the fungus is grown on a synthetic nutrient medium containing optimal concentrations of fructose, KNO3, KH2PO4, MgSO4, and ZnSO4. Arginine and biotin operate in very low concentrations which exclude unspecific nutrient effects. In spite of the complicated interactions of arginine and biotin which are shown qualitatively (Figs. 3 and 4a) and quantitatively (Figs. 2 and 4b), the following conclusions are reached: 1. In the absence of biotin, the development of Sordaria macrospora is blocked at the stage of small protoperithecia. The external addition of biotin (optimal concentration: 3-12 μg/l) allows the formation of fertile fruiting bodies. This effect cannot be imitated by arginine. The biotin effect is discussed in connection with stimulated RNA synthesis.-2. The developmental velocity is influenced by the external addition of arginine. Without arginine but at permissible biotin concentrations, the total life cycle takes about 10 days, in the presence of arginine (1 mM), however, about 6 days.-3. The hyphal density, as well as the total number of fruiting bodies being produced, is controlled in a similar manner by biotin and arginine. The induction of fruiting body formation obviously takes place after the transgression of a critical hyphal density.

  4. Correlation of the L-Arginine Pathway with Thrombo-Inflammation May Contribute to the Outcome of Acute Ischemic Stroke

    DEFF Research Database (Denmark)

    Molnar, Tihamer; Pusch, Gabriella; Nagy, Lajos

    2016-01-01

    BACKGROUND: Immune responses contribute to secondary injury after acute ischemic stroke (AIS), and metabolites of the L-arginine pathway are associated with stroke outcome. Here, we analyzed the relationship of the L-arginine pathway with thrombo-inflammatory biomarkers in AIS and their additive...... and independent associations to outcome. METHODS: Serial changes in P-selectin, tPA, MCP-1, sCD40L, IL-6, IL-8, L-arginine, and asymmetric and symmetric dimethylarginine (ADMA, SDMA) were investigated in 55 patients with AIS and without infection within 6 and 72 hours after stroke onset. Outcomes were assessed...... as National Institutes of Health Stroke Scale (NIHSS) worsening by 24 hours, poststroke infection, and death by 1 month. RESULTS: Serum levels of L-arginine showed negative correlation, whereas ADMA and SDMA showed positive correlation with thrombo-inflammatory biomarkers in the hyperacute phase. Most...

  5. Arginine-vasopressin stimulates the formation of phosphatidic acid in rat Leydig cells

    DEFF Research Database (Denmark)

    Nielsen, J.R.; Hansen, Harald S.; Jensen, B.

    1987-01-01

    Arginine-vasopressin (AVP) stimulated the formation of labelled phosphatidic acid (PA) in [C]arachidonic acid-prelabelled rat Leydig cells. After addition of 10 M AVP [C]arachidonoylphosphatidic acid reached a maximum within 2 min. The increase was dose-dependent (10-10 M). No change in labelling...

  6. Chemical modifications in solarized soil with addition of organic residues/
    Modificações químicas em solo solarizado, com e sem incorporação de resíduos orgânicos

    OpenAIRE

    Carlos Roberto Padovani; Elisangela Marques Jeronimo; Marcelo de Almeida Silva; Nilton Luiz de Souza; Marli Teixeira de Almeida Minhoni; Glauber José de Castro Gava; Juliana Cristina Sodário Cruz

    2008-01-01

    The soil solarization is used in small properties as an alternative for control of phytopathogens and weeds, besides it also can affect the availability of some nutrients and phytotoxic elements in the soil. Thus, one experiment was carried out as a three-factor factorial (solarized and not solarized soil x with and without addition of vegetable residue x four collection times) for evaluation of variations of pH, organic matter, phosphorus, total nitrogen, potassium, calcium, magnesium and al...

  7. Do wood-based panels made with agro-industrial residues provide environmentally benign alternatives? An LCA case study of sugarcane bagasse addition to particle board manufacturing

    DEFF Research Database (Denmark)

    Silva, Diogo Aparecido Lopes; Lahr, Francisco Antonio Rocco; Pavan, Ana Laura Raymundo

    2014-01-01

    environmental impacts? Could it substitute wood as raw material? Accordingly, this paper presents a life cycle assessment (LCA) study of particle board manufactured with sugarcane bagasse residues.The cradle-to-gate assessment of 1 m3 of particle board made with sugarcane bagasse (PSB) considered three main...... subsystem was 9.08 % (economic base). The potential environmental impact phase was assessed by applying the CML and USEtox methods. PSB was compared with the conventional particle board manufactured in Brazil by the categories of the CML and USETox, and including land use indicators. Finally, two scenarios......, it is suggested that the sugarcane bagasse be mixed up to 75 % during particle board manufacturing so that good quality properties and environmental performance of panels can be provided....

  8. Role of arginine-292 in the substrate specificity of aspartate aminotransferase as examined by site-directed mutagenesis

    International Nuclear Information System (INIS)

    Cronin, C.N.; Kirsch, J.F.

    1988-01-01

    X-ray crystallographic data have implicated Arg-292 as the residue responsible for the preferred side-chain substrate specificity of asparate aminotransferase. It forms a salt bridge with the β or γ carboxylate group of the substrate. In order to test this proposal and, in addition, to attempt to reverse the substrate charge specificity of this enzyme, Arg-292 has been converted to Asp-292 by site-directed mutagenesis. The activity k/sub cat//K/sub M/) of the mutant enzyme, R292D, toward the natural anionic substrates L-aspartate, L-glutamate, and α-ketoglutarate is depressed by over 5 orders of magnitude, whereas the activity toward the keto acid pyruvate and a number of aromatic and other neutral amino acids is reduced by only 2-9-fold. These results confirm the proposal that Arg-292 is critical for the rapid turnover of substrates bearing anionic side chains and show further that, apart from the desired alteration no major perturbations of the remainder of the molecule have been made. The activity of R292D toward the cationic amino acids L-arginine, L-lysine, and L-ornithine is increased by 9-16-fold over that of wild type and the ratio (k/sub cat//K/sub M/)/sub cationic//(k/sub cat//K/sub M/)/sub anionic/ is in the range 2-40-fold for R292D, whereas this ratio has a range of [(0.3-6) x 10 -6 ]-fold for wild type. Thus, the mutation has produced an inversion of the substrate charge specificity. Possible explanations for the less-than-expected reactivity of R292D with arginine are discussed

  9. Arginine Vasotocin, the Social Neuropeptide of Amphibians and Reptiles.

    Science.gov (United States)

    Wilczynski, Walter; Quispe, Maricel; Muñoz, Matías I; Penna, Mario

    2017-01-01

    Arginine vasotocin (AVT) is the non-mammalian homolog of arginine vasopressin (AVP) and, like vasopressin, serves as an important modulator of social behavior in addition to its peripheral functions related to osmoregulation, reproductive physiology, and stress hormone release. In amphibians and reptiles, the neuroanatomical organization of brain AVT cells and fibers broadly resembles that seen in mammals and other taxa. Both parvocellular and magnocellular AVT-containing neurons are present in multiple populations located mainly in the basal forebrain from the accumbens-amygdala area to the preoptic area and hypothalamus, from which originate widespread fiber connections spanning the brain with a particularly heavy innervation of areas associated with social behavior and decision-making. As for mammalian AVP, AVT is present in greater amounts in males in many brain areas, and its presence varies seasonally, with hormonal state, and in males with differing social status. AVT's social influence is also conserved across herpetological taxa, with significant effects on social signaling and aggression, and, based on the very small number of studies investigating more complex social behaviors in amphibians and reptiles, AVT may also modulate parental care and social bonding when it is present in these vertebrates. Within this conserved pattern, however, both AVT anatomy and social behavior effects vary significantly across species. Accounting for this diversity represents a challenge to understanding the mechanisms by which AVT exerts its behavioral effects, as well are a potential tool for discerning the structure-function relationships underlying AVT's many effects on behavior.

  10. Effects of arginine on multimodal anion exchange chromatography.

    Science.gov (United States)

    Hirano, Atsushi; Arakawa, Tsutomu; Kameda, Tomoshi

    2015-12-01

    The effects of arginine on binding and elution properties of a multimodal anion exchanger, Capto adhere, were examined using bovine serum albumin (BSA) and a monoclonal antibody against interleukin-8 (mAb-IL8). Negatively charged BSA was bound to the positively charged Capto adhere and was readily eluted from the column with a stepwise or gradient elution using 1M NaCl at pH 7.0. For heat-treated BSA, small oligomers and remaining monomers were also eluted using a NaCl gradient, whereas larger oligomers required arginine for effective elution. The positively charged mAb-IL8 was bound to Capto adhere at pH 7.0. Arginine was also more effective for elution of the bound mAb-IL8 than was NaCl. The results imply that arginine interacts with the positively charged Capto adhere. The mechanism underlying the interactions of arginine with Capto adhere was examined by calculating the binding free energy between an arginine molecule and a Capto adhere ligand in water through molecular dynamics simulations. The overall affinity of arginine for Capto adhere is attributed to the hydrophobic and π-π interactions between an arginine side chain and the aromatic moiety of the ligand as well as hydrogen bonding between arginine and the ligand hydroxyl group, which may account for the characteristics of protein elution using arginine. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. Supplementation with a combination of beta-hydroxy-beta-methylbutyrate (HMB), arginine, and glutamine is safe and could improve hematological parameters.

    Science.gov (United States)

    Rathmacher, J A; Nissen, S; Panton, L; Clark, R H; Eubanks May, P; Barber, A E; D'Olimpio, J; Abumrad, N N

    2004-01-01

    Combining the amino acids arginine and glutamine with the leucine metabolite beta-hydroxy-beta-methylbutyrate (HMB) has been shown to reverse lean tissue loss in cancer and acquired immunodeficiency syndrome (AIDS) patients. Although each of these nutrients has been shown to be safe, the safety of this mixture has not been reported. Three double-blind studies examined the safety of the combination of HMB, arginine and glutamine on blood chemistries, hematology, emotional profile, and adverse events. Study 1 was conducted in healthy adult males (n = 34), study 2 was in HIV patients with AIDS-associated weight loss (n = 43), and study 3 was in cancer patients with wasting (n = 32). Volunteers were assigned to either a placebo or a mixture of 3 g HMB, 14 g arginine, and 14 g glutamine per day. Across the 3 studies, HMB, arginine, and glutamine supplementation was not associated with any adverse indicators of health. The only significant changes noted were positive indicators of health status. HMB, arginine, and glutamine supplementation was associated with an improvement in emotional profile (p = .05), a decreased feeling of weakness (p = .03), and increased red blood cells, hemoglobin, hematocrit, lymphocytes, and eosinophils (p HMB, arginine, and glutamine supplementation, which was possibly caused by the additional nitrogen consumed or to the fact that ureagenesis is influenced by arginine and glutamine supplementation. These results show that HMB, arginine, and glutamine can be safely used to treat muscle wasting associated with AIDS and cancer.

  12. Mutational analysis to identify the residues essential for the inhibition of N-acetyl glutamate kinase of Corynebacterium glutamicum.

    Science.gov (United States)

    Huang, Yuanyuan; Zhang, Hao; Tian, Hongming; Li, Cheng; Han, Shuangyan; Lin, Ying; Zheng, Suiping

    2015-09-01

    N-acetyl glutamate kinase (NAGK) is a key enzyme in the synthesis of L-arginine that is inhibited by its end product L-arginine in Corynebacterium glutamicum (C. glutamicum). In this study, the potential binding sites of arginine and the residues essential for its inhibition were identified by homology modeling, inhibitor docking, and site-directed mutagenesis. The allosteric inhibition of NAGK was successfully alleviated by a mutation, as determined through analysis of mutant enzymes, which were overexpressed in vivo in C. glutamicum ATCC14067. Analysis of the mutant enzymes and docking analysis demonstrated that residue W23 positions an arginine molecule, and the interaction between arginine and residues L282, L283, and T284 may play an important role in the remote inhibitory process. Based on the results of the docking analysis of the effective mutants, we propose a linkage mechanism for the remote allosteric regulation of NAGK activity, in which residue R209 may play an essential role. In this study, the structure of the arginine-binding site of C. glutamicum NAGK (CgNAGK) was successfully predicted and the roles of the relevant residues were identified, providing new insight into the allosteric regulation of CgNAGK activity and a solid platform for the future construction of an optimized L-arginine producing strain.

  13. Additional correction of OAB symptoms by two anti-muscarinics for men over 50 years old with residual symptoms of moderate prostatic obstruction after treatment with Tamsulosin.

    Science.gov (United States)

    Kosilov, Kirill; Loparev, Sergey; Ivanovskaya, Marina; Kosilova, Liliya

    2015-03-01

    To study the effectiveness and safety of combined standard-dosed Solifenacin and Trospium for management of symptoms of overactive bladder (OAB) in elderly patients after the treatment with Tamsulosin. A total of 417 men over 50 years of age (average age 57.9 (8.3)) with diagnosed prostatic obstruction (score 8-19 according to I-PSS), who had not taken Tamsulosin before, were enrolled in the study. I-PSS questionnaire (from 8 to 19 - moderate) and Awareness Tool questionnaire for evaluating OAB symptoms (total score for OAB symptoms over 8) were used at the beginning and at the end of the observation. Also, urodynamic parameters were examined. Percentage of patients with prevalent symptoms of obstruction of urethra decreases after the treatment with Tamsulosin and then rises again (36.2%), but absolute number of patients remains smaller than initial data. Percentage of patients with relative prevalence of symptoms of overactive bladder slightly increases against administration of Tamsulosin and reaches initial values at the time of administration of anti-muscarinic drugs with absolute decrease in number of such patients. Combination of Trospium and Solifenacin is an effective way to manage residual symptoms of hyperactive bladder during treatment of early obstruction of urinary bladder.

  14. Action of arginine for protection of ulcerative colitis by dextran sodium sulphate (DSS)

    International Nuclear Information System (INIS)

    Andrade, Maria Emilia Rabelo

    2016-01-01

    Recent studies have demonstrated the benefits of immunomodulators, such as arginine, in the regulation of inflammatory responses and trophism of the intestinal mucosa. The aim of this study was to evaluate the possible mechanisms action of arginine (pretreatment or treatment) in experimental model of ulcerative colitis induced by dextran sodium sulfate (DSS). C57BL/6 mice were randomized into 5 groups: Control group (C): standard diet and water; Arginine group (ARG): diet supplementation with arginine and water; Colitis group (COL): standard diet and DSS solution; Pretreated group (PT): diet supplementation with arginine before and during colitis induction; Treated group (T): diet supplementation with arginine during colitis induction. Colitis was induced by administration of 1.5% DSS for 5 days. After this, all the mice were euthanized and blood, organs and intestinal fluid were collected for carrying out analyzes. Parameters such as intestinal permeability (IP), bacterial translocation (BT), histological analysis (histological score, morphometric analysis, collagen and mucins stain), nitrate and nitrite, cytokines and chemokines, secretory immunoglobulin A (sIgA), inflammatory infiltrate and oxidative stress were performed. The ARG group did not show difference compared to group C in the investigated parameters (C vs ARG: p> 0.05). The COL group showed increased IP (C vs COL: p < 0.05) and BT (C vs COL: p <0.05). In the histological analysis, the COL group showed severe inflammation and reduction the crypts length. In addition, in the group COL observed increase infiltration of eosinophils, neutrophils and macrophages in the colon, increase cytokine IL-17 and chemokine KC in serum and oxidative stress in the colon (COL vs C: p <0.05). In the arginine-supplemented groups (PT and T) was observed decrease IP and BT to blood, liver and lung (PT and T vs Col: p <0.05). Histological analysis showed that the arginine (PT and T) preserved the intestinal mucosa and crypts

  15. Expanding the clinical and molecular spectrum of PRMT7 mutations: 3 additional patients and review.

    Science.gov (United States)

    Agolini, E; Dentici, M L; Bellacchio, E; Alesi, V; Radio, F C; Torella, A; Musacchia, F; Tartaglia, M; Dallapiccola, B; Nigro, V; Digilio, M C; Novelli, A

    2018-03-01

    Protein arginine methyltransferase 7 (PRMT7) is a member of a family of enzymes that catalyze the transfer of methyl groups from S-adenosyl-l-methionine to nitrogen atoms on arginine residues. Arginine methylation is involved in multiple biological processes, such as signal transduction, mRNA splicing, transcriptional control, DNA repair, and protein translocation. Currently, 7 patients have been described harboring compound heterozygous or homozygous variants in the PRMT7 gene, causing a novel intellectual disability syndrome, known as SBIDDS syndrome (Short Stature, Brachydactyly, Intellectual Developmental Disability, and Seizures). We report on 3 additional patients from 2 consanguineous families with severe/moderate intellectual disability, short stature, brachydactyly and dysmorphisms. Exome sequencing revealed 2 novel homozygous mutations in PRMT7. Our findings expand the clinical and molecular spectrum of homozygous PRMT7 mutations, associated to the SBIDDS syndrome, showing a possible correlation between the type of mutation and the severity of the phenotype. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  16. A glutamate/aspartate switch controls product specificity in a protein arginine methyltransferase

    Energy Technology Data Exchange (ETDEWEB)

    Debler, Erik W.; Jain, Kanishk; Warmack, Rebeccah A.; Feng, You; Clarke, Steven G.; Blobel, Günter; Stavropoulos, Pete

    2016-02-08

    Trypanosoma brucei PRMT7 (TbPRMT7) is a protein arginine methyltransferase (PRMT) that strictly monomethylates various substrates, thus classifying it as a type III PRMT. However, the molecular basis of its unique product specificity has remained elusive. Here, we present the structure of TbPRMT7 in complex with its cofactor product S-adenosyl-L-homocysteine (AdoHcy) at 2.8 Å resolution and identify a glutamate residue critical for its monomethylation behavior. TbPRMT7 comprises the conserved methyltransferase and β-barrel domains, an N-terminal extension, and a dimerization arm. The active site at the interface of the N-terminal extension, methyltransferase, and β-barrel domains is stabilized by the dimerization arm of the neighboring protomer, providing a structural basis for dimerization as a prerequisite for catalytic activity. Mutagenesis of active-site residues highlights the importance of Glu181, the second of the two invariant glutamate residues of the double E loop that coordinate the target arginine in substrate peptides/proteins and that increase its nucleophilicity. Strikingly, mutation of Glu181 to aspartate converts TbPRMT7 into a type I PRMT, producing asymmetric dimethylarginine (ADMA). Isothermal titration calorimetry (ITC) using a histone H4 peptide showed that the Glu181Asp mutant has markedly increased affinity for monomethylated peptide with respect to the WT, suggesting that the enlarged active site can favorably accommodate monomethylated peptide and provide sufficient space for ADMA formation. In conclusion, these findings yield valuable insights into the product specificity and the catalytic mechanism of protein arginine methyltransferases and have important implications for the rational (re)design of PRMTs.

  17. Radioimmunoassay of arginine vasopressin (AVP) and clinical application

    International Nuclear Information System (INIS)

    Wagner, H.; Haeberle, M.; Franz, H.E.; Maier, V.

    1977-01-01

    The low circulating levels of vasopressin required an initial extraction procedure. The extraction method itself presented problems with the specificity and the reproducibility of the extracted hormone from serum. The presented paper describes the developement of a radioimmunoassay without an extraction procedure. The AVP was coupled with rabbit-albumin by gluteraldehyde condensation for the immunization of rabbits. Synthetic AVP was iodinated by the method of GREENWOOD and HUNTER (1963) and purified by the addition of Dowex. The antibody cannot differentiate between lysine- and arginine-, ornithine-, glycerine - vasopressin and oxytocin. 1 - 24 ACTH and gastrin did not crosscreact. Normal subjects were found to have 5.7 +- 4.4/uU/ml after a dehydration period of 12 hours. Subjects suffering from psychogenic polydipsia showed normal levels, however, different forms of stress yielded higher levels in normal subjects. In patients suffering from liver cirrhosis the values normalized when ascites was under control. (orig.) [de

  18. Application of dispersive solid-phase extraction and ultra-fast liquid chromatography-tandem quadrupole mass spectrometry in food additive residue analysis of red wine.

    Science.gov (United States)

    Chen, Xiao-Hong; Zhao, Yong-Gang; Shen, Hao-Yu; Jin, Mi-Cong

    2012-11-09

    A novel and effective dispersive solid-phase extraction (dSPE) procedure with rapid magnetic separation using ethylenediamine-functionalized magnetic polymer as an adsorbent was developed. The new procedure had excellent clean-up ability for the selective removal of the matrix in red wine. An accurate, simple, and rapid analytical method using ultra-fast liquid chromatography-tandem quadrupole mass spectrometry (UFLC-MS/MS) for the simultaneous determination of nine food additives (i.e., acesulfame, saccharin, sodium cyclamate, aspartame, benzoic acid, sorbic acid, stevioside, dehydroacetic acid, and neotame) in red wine was also used and validated. Recoveries ranging from 78.5% to 99.2% with relative standard deviations ranging from 0.46% to 6.3% were obtained using the new method. All target compounds showed good linearities in the tested range with correlation coefficients (r) higher than 0.9993. The limits of quantification for the nine food additives were between 0.10 μg/L and 50.0 μg/L. The proposed dSPE-UFLC-MS/MS method was successfully applied in the food-safety risk monitoring of real red wine in Zhejiang Province, China. Crown Copyright © 2012. Published by Elsevier B.V. All rights reserved.

  19. Characterization of arginine decarboxylase from Dianthus caryophyllus.

    Science.gov (United States)

    Ha, Byung Hak; Cho, Ki Joon; Choi, Yu Jin; Park, Ky Young; Kim, Kyung Hyun

    2004-04-01

    Arginine decarboxylase (ADC, EC 4.1.1.9) is a key enzyme in the biosynthesis of polyamines in higher plants, whereas ornithine decarboxylase represents the sole pathway of polyamine biosynthesis in animals. Previously, we characterized a genomic clone from Dianthus caryophyllus, in which the deduced polypeptide of ADC was 725 amino acids with a molecular mass of 78 kDa. In the present study, the ADC gene was subcloned into the pGEX4T1 expression vector in combination with glutathione S-transferase (GST). The fusion protein GST-ADC was water-soluble and thus was purified by sequential GSTrap-arginine affinity chromatography. A thrombin-mediated on-column cleavage reaction was employed to release free ADC from GST. Hiload superdex gel filtration FPLC was then used to obtain a highly purified ADC. The identity of the ADC was confirmed by immunoblot analysis, and its specific activity with respect to (14)C-arginine decarboxylation reaction was determined to be 0.9 CO(2) pkat mg(-1) protein. K(m) and V(max) of the reaction between ADC and the substrate were 0.077 +/- 0.001 mM and 6.0 +/- 0.6 pkat mg(-1) protein, respectively. ADC activity was reduced by 70% in the presence of 0.1 mM Cu(2+) or CO(2+), but was only marginally affected by Mg(2+), or Ca(2+) at the same concentration. Moreover, spermine at 1 mM significantly reduced its activity by 30%.

  20. Weissella halotolerans W22 combines arginine deiminase and ornithine decarboxylation pathways and converts arginine to putrescine

    NARCIS (Netherlands)

    Pereira, C. I.; San Romao, M. V.; Lolkema, J. S.; Barreto Crespo, M. T.; Baretto Crespo, M.

    2009-01-01

    Aims: To demonstrate that the meat food strain Weissella halotolerans combines an ornithine decarboxylation pathway and an arginine deiminase (ADI) pathway and is able to produce putrescine, a biogenic amine. Evidence is shown that these two pathways produce a proton motive force (PMF). Methods and

  1. Characterization of four arginine kinases in the ciliate Paramecium tetraurelia: Investigation on the substrate inhibition mechanism.

    Science.gov (United States)

    Yano, Daichi; Suzuki, Takaya; Hirokawa, Saki; Fuke, Kyoko; Suzuki, Tomohiko

    2017-08-01

    The ciliate Paramecium tetraurelia contains four arginine kinase genes (AK1-4). We detected cDNA for only three of the AKs (AK1-3) via PCR. Recombinant AK1-4 were expressed in Escherichia coli and their kinetics parameters determined. AK3 showed typical substrate inhibition toward arginine, and enzymatic activity markedly decreased when arginine concentration increased. This is the first example of substrate inhibition in wild-type phosphagen kinases. To explore the substrate inhibition mechanism, site-directed mutations were generated, targeting the amino acid sequence D-D-S-Q-V at positions 77-81 in P. tetraurelia AK3. Among the mutants, substrate inhibition was lost remarkably in the S79A mutant. In spite of high amino acid sequence identity (91%) between P. tetraurelia AK3 and AK4, the enzymatic activity of AK4 was less by 3% than that of AK3. We noticed that the conservative G298 was unusually replaced by R in P. tetraurelia AK4, and we constructed two mutants, R298G/AK4 and G298R/AK3. Enzymatic activity of the former mutant was comparable with that of the wild-type AK3, whereas that of the latter mutant was dramatically reduced. Thus, we concluded that the significantly low activity of P. tetraurelia AK4 is due to the residue R298. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Deceleration of arginine kinase refolding by induced helical structures.

    Science.gov (United States)

    Li, Hai-Long; Zhou, Sheng-Mei; Park, Daeui; Jeong, Hyoung Oh; Chung, Hae Young; Yang, Jun-Mo; Meng, Fan-Guo; Hu, Wei-Jiang

    2012-04-01

    Arginine kinase (AK) is a key metabolic enzyme for keeping energy balance in invertebrates. Therefore, regulation of the enzymatic activity and the folding studies of AK from the various invertebrates have been the focus of investigation. We studied the effects of helical structures by using hexafluoroisopropanol (HFIP) on AK folding. Folding kinetic studies showed that the folding rates of the urea-denatured AKs were significantly decelerated after being induced in various concentrations of HFIP. AK lost its activity completely at concentrations greater than 60%. The results indicated that the HFIP-induced helical structures in the denatured state play a negative role in protein folding, and the helical structures induced in 5% (v/v) HFIP act as the most effective barrier against AK taking its native structure. The computational docking simulations (binding energies for -2.19 kcal/mol for AutoDock4.2 and -20.47 kcal/mol for Dock6.3) suggested that HFIP interacts with the several important residues that are predicted by both programs. The excessively pre-organized helical structures not only hampered the folding process, but also ultimately brought about changes in the three-dimensional conformation and biological function of AK.

  3. Arginine, citrulline and nitric oxide metabolism in sepsis

    Science.gov (United States)

    Arginine has vasodilatory effects, via its conversion by nitric oxide (NO) synthase into NO, and immunomodulatory actions that play important roles in sepsis. Protein breakdown affects arginine availability, and the release of asymmetric dimethylarginine, an inhibitor of NO synthase, may therefore a...

  4. Functional and neurochemical profile of place learning after L-nitro-arginine in the rat

    DEFF Research Database (Denmark)

    Mogensen, Jesper; Wörtwein, Gitta; Hasman, Andreas

    1995-01-01

    Neurobiology, nitrogenoxid (NO), place learning, rotte, L-Nitro-Arginin, funktionel genopretning......Neurobiology, nitrogenoxid (NO), place learning, rotte, L-Nitro-Arginin, funktionel genopretning...

  5. Arginase treatment prevents the recovery of canine lymphoma and osteosarcoma cells resistant to the toxic effects of prolonged arginine deprivation.

    Science.gov (United States)

    Wells, James W; Evans, Christopher H; Scott, Milcah C; Rütgen, Barbara C; O'Brien, Timothy D; Modiano, Jaime F; Cvetkovic, Goran; Tepic, Slobodan

    2013-01-01

    Rapidly growing tumor cells require a nutrient-rich environment in order to thrive, therefore, restricting access to certain key amino acids, such as arginine, often results in the death of malignant cells, which frequently display defective cell cycle check-point control. Healthy cells, by contrast, become quiescent and remain viable under arginine restriction, displaying full recovery upon return to arginine-rich conditions. The use of arginase therapy to restrict available arginine for selectively targeting malignant cells is currently under investigation in human clinical trials. However, the suitability of this approach for veterinary uses is unexplored. As a prelude to in vivo studies in canine malignancies, we examined the in vitro effects of arginine-deprivation on canine lymphoid and osteosarcoma cell lines. Two lymphoid and 2 osteosarcoma cell lines were unable to recover following 6 days of arginine deprivation, but all remaining cell lines displayed full recovery upon return to arginine-rich culture conditions. These remaining cell lines all proved susceptible to cell death following the addition of arginase to the cultures. The lymphoid lines were particularly sensitive to arginase, becoming unrecoverable after just 3 days of treatment. Two of the osteosarcoma lines were also susceptible over this time-frame; however the other 3 lines required 6-8 days of arginase treatment to prevent recovery. In contrast, adult progenitor cells from the bone marrow of a healthy dog were able to recover fully following 9 days of culture in arginase. Over 3 days in culture, arginase was more effective than asparaginase in inducing the death of lymphoid lines. These results strongly suggest that short-term arginase treatment warrants further investigation as a therapy for lymphoid malignancies and osteosarcomas in dogs.

  6. Arginase treatment prevents the recovery of canine lymphoma and osteosarcoma cells resistant to the toxic effects of prolonged arginine deprivation.

    Directory of Open Access Journals (Sweden)

    James W Wells

    Full Text Available Rapidly growing tumor cells require a nutrient-rich environment in order to thrive, therefore, restricting access to certain key amino acids, such as arginine, often results in the death of malignant cells, which frequently display defective cell cycle check-point control. Healthy cells, by contrast, become quiescent and remain viable under arginine restriction, displaying full recovery upon return to arginine-rich conditions. The use of arginase therapy to restrict available arginine for selectively targeting malignant cells is currently under investigation in human clinical trials. However, the suitability of this approach for veterinary uses is unexplored. As a prelude to in vivo studies in canine malignancies, we examined the in vitro effects of arginine-deprivation on canine lymphoid and osteosarcoma cell lines. Two lymphoid and 2 osteosarcoma cell lines were unable to recover following 6 days of arginine deprivation, but all remaining cell lines displayed full recovery upon return to arginine-rich culture conditions. These remaining cell lines all proved susceptible to cell death following the addition of arginase to the cultures. The lymphoid lines were particularly sensitive to arginase, becoming unrecoverable after just 3 days of treatment. Two of the osteosarcoma lines were also susceptible over this time-frame; however the other 3 lines required 6-8 days of arginase treatment to prevent recovery. In contrast, adult progenitor cells from the bone marrow of a healthy dog were able to recover fully following 9 days of culture in arginase. Over 3 days in culture, arginase was more effective than asparaginase in inducing the death of lymphoid lines. These results strongly suggest that short-term arginase treatment warrants further investigation as a therapy for lymphoid malignancies and osteosarcomas in dogs.

  7. Arginine affects appetite via nitric oxide in ducks.

    Science.gov (United States)

    Wang, C; Hou, S S; Huang, W; Xu, T S; Rong, G H; Xie, M

    2014-08-01

    The objective of the study was to investigate the mechanism by which arginine regulates feed intake in Pekin ducks. In experiment 1, one hundred forty-four 1-d-old male Pekin ducks were randomly allotted to 3 dietary treatments with 6 replicate pens of 8 birds per pen. Birds in each group were fed a corn-corn gluten meal diet containing 0.65, 0.95, and 1.45% arginine. Ducks fed the diet containing 0.65% arginine had lower feed intake and plasma nitric oxide level (P ducks were allotted to 1 of 2 treatments. After 2 h fasting, birds in the 2 groups were intraperitoneally administrated saline and l-NG-nitro-arginine methyl ester HCl (L-NAME) for 3 d, respectively. Feed intake (P study implied that arginine modifies feeding behavior possibly through controlling endogenous synthesis of nitric oxide in Pekin ducks. © Poultry Science Association Inc.

  8. Purification of free arginine from chickpea (Cicer arietinum) seeds.

    Science.gov (United States)

    Cortés-Giraldo, Isabel; Megías, Cristina; Alaiz, Manuel; Girón-Calle, Julio; Vioque, Javier

    2016-02-01

    Chickpea is a grain legume widely consumed in the Mediterranean region and other parts of the world. Chickpea seeds are rich in proteins but they also contain a substantial amount of free amino acids, especially arginine. Hence chickpea may represent a useful source of free amino acids for nutritional or pharmaceutical purposes. Arginine is receiving great attention in recent years because it is the substrate for the synthesis of nitric oxide, an important signaling molecule involved in numerous physiological and pathological processes in mammals. In this work we describe a simple procedure for the purification of arginine from chickpea seeds, using nanofiltration technology and an ion-exchange resin, Amberlite IR-120. Arginine was finally purified by precipitation or crystallization, yielding preparations with purities of 91% and 100%, respectively. Chickpea may represent an affordable green source of arginine, and a useful alternative to production by fermentation or protein hydrolysis. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Arginine Vasotocin, the Social Neuropeptide of Amphibians and Reptiles

    Science.gov (United States)

    Wilczynski, Walter; Quispe, Maricel; Muñoz, Matías I.; Penna, Mario

    2017-01-01

    Arginine vasotocin (AVT) is the non-mammalian homolog of arginine vasopressin (AVP) and, like vasopressin, serves as an important modulator of social behavior in addition to its peripheral functions related to osmoregulation, reproductive physiology, and stress hormone release. In amphibians and reptiles, the neuroanatomical organization of brain AVT cells and fibers broadly resembles that seen in mammals and other taxa. Both parvocellular and magnocellular AVT-containing neurons are present in multiple populations located mainly in the basal forebrain from the accumbens–amygdala area to the preoptic area and hypothalamus, from which originate widespread fiber connections spanning the brain with a particularly heavy innervation of areas associated with social behavior and decision-making. As for mammalian AVP, AVT is present in greater amounts in males in many brain areas, and its presence varies seasonally, with hormonal state, and in males with differing social status. AVT’s social influence is also conserved across herpetological taxa, with significant effects on social signaling and aggression, and, based on the very small number of studies investigating more complex social behaviors in amphibians and reptiles, AVT may also modulate parental care and social bonding when it is present in these vertebrates. Within this conserved pattern, however, both AVT anatomy and social behavior effects vary significantly across species. Accounting for this diversity represents a challenge to understanding the mechanisms by which AVT exerts its behavioral effects, as well are a potential tool for discerning the structure-function relationships underlying AVT’s many effects on behavior. PMID:28824546

  10. Arginine Vasotocin, the Social Neuropeptide of Amphibians and Reptiles

    Directory of Open Access Journals (Sweden)

    Walter Wilczynski

    2017-08-01

    Full Text Available Arginine vasotocin (AVT is the non-mammalian homolog of arginine vasopressin (AVP and, like vasopressin, serves as an important modulator of social behavior in addition to its peripheral functions related to osmoregulation, reproductive physiology, and stress hormone release. In amphibians and reptiles, the neuroanatomical organization of brain AVT cells and fibers broadly resembles that seen in mammals and other taxa. Both parvocellular and magnocellular AVT-containing neurons are present in multiple populations located mainly in the basal forebrain from the accumbens–amygdala area to the preoptic area and hypothalamus, from which originate widespread fiber connections spanning the brain with a particularly heavy innervation of areas associated with social behavior and decision-making. As for mammalian AVP, AVT is present in greater amounts in males in many brain areas, and its presence varies seasonally, with hormonal state, and in males with differing social status. AVT’s social influence is also conserved across herpetological taxa, with significant effects on social signaling and aggression, and, based on the very small number of studies investigating more complex social behaviors in amphibians and reptiles, AVT may also modulate parental care and social bonding when it is present in these vertebrates. Within this conserved pattern, however, both AVT anatomy and social behavior effects vary significantly across species. Accounting for this diversity represents a challenge to understanding the mechanisms by which AVT exerts its behavioral effects, as well are a potential tool for discerning the structure-function relationships underlying AVT’s many effects on behavior.

  11. Redox Specificity of 2-Hydroxyacid-Coupled NAD+/NADH Dehydrogenases: A Study Exploiting “Reactive” Arginine as a Reporter of Protein Electrostatics

    Science.gov (United States)

    Durani, Susheel

    2013-01-01

    With “reactive” arginine as a kinetic reporter, 2-hydroxyacid dehydrogenases are assessed in basis of their specialization as NAD+-reducing or NADH-oxidizing enzymes. Specifically, M4 and H4 lactate dehydrogenases (LDHs) and cytoplasmic and mitochondrial malate dehydrogenases (MDHs) are compared to assess if their coenzyme specificity may involve electrostatics of cationic or neutral nicotinamide structure as the basis. The enzymes from diverse eukaryote and prokaryote sources thus are assessed in “reactivity” of functionally-critical arginine as a function of salt concentration and pH. Electrostatic calculations were performed on “reactive” arginines and found good correspondence with experiment. The reductive and oxidative LDHs and MDHs are assessed in their count over ionizable residues and in placement details of the residues in their structures as proteins. The variants found to be high or low in ΔpKa of “reactive” arginine are found to be also strong or weak cations that preferentially oxidize NADH (neutral nicotinamide structure) or reduce NAD+ (cationic nicotinamide structure). The ionized groups of protein structure may thus be important to redox specificity of the enzyme on basis of electrostatic preference for the oxidized (cationic nicotinamide) or reduced (neutral nicotinamide) coenzyme. Detailed comparisons of isozymes establish that the residues contributing in their redox specificity are scrambled in structure of the reductive enzyme. PMID:24391777

  12. Redox specificity of 2-hydroxyacid-coupled NAD(+/NADH dehydrogenases: a study exploiting "reactive" arginine as a reporter of protein electrostatics.

    Directory of Open Access Journals (Sweden)

    Pooja Gupta

    Full Text Available With "reactive" arginine as a kinetic reporter, 2-hydroxyacid dehydrogenases are assessed in basis of their specialization as NAD(+-reducing or NADH-oxidizing enzymes. Specifically, M4 and H4 lactate dehydrogenases (LDHs and cytoplasmic and mitochondrial malate dehydrogenases (MDHs are compared to assess if their coenzyme specificity may involve electrostatics of cationic or neutral nicotinamide structure as the basis. The enzymes from diverse eukaryote and prokaryote sources thus are assessed in "reactivity" of functionally-critical arginine as a function of salt concentration and pH. Electrostatic calculations were performed on "reactive" arginines and found good correspondence with experiment. The reductive and oxidative LDHs and MDHs are assessed in their count over ionizable residues and in placement details of the residues in their structures as proteins. The variants found to be high or low in ΔpKa of "reactive" arginine are found to be also strong or weak cations that preferentially oxidize NADH (neutral nicotinamide structure or reduce NAD(+ (cationic nicotinamide structure. The ionized groups of protein structure may thus be important to redox specificity of the enzyme on basis of electrostatic preference for the oxidized (cationic nicotinamide or reduced (neutral nicotinamide coenzyme. Detailed comparisons of isozymes establish that the residues contributing in their redox specificity are scrambled in structure of the reductive enzyme.

  13. Murine elongation factor 1 alpha (EF-1 alpha) is posttranslationally modified by novel amide-linked ethanolamine-phosphoglycerol moieties. Addition of ethanolamine-phosphoglycerol to specific glutamic acid residues on EF-1 alpha

    International Nuclear Information System (INIS)

    Whiteheart, S.W.; Shenbagamurthi, P.; Chen, L.; Cotter, R.J.; Hart, G.W.

    1989-01-01

    Elongation Factor 1 alpha (EF-1 alpha), an important eukaryotic translation factor, transports charged aminoacyl-tRNA from the cytosol to the ribosomes during poly-peptide synthesis. Metabolic radiolabeling with [ 3 H] ethanolamine shows that, in all cells examined, EF-1 alpha is the major radiolabeled protein. Radiolabeled EF-1 alpha has an apparent Mr = 53,000 and a basic isoelectric point. It is cytosolic and does not contain N-linked oligosaccharides. Trypsin digestion of murine EF-1 alpha generated two major [ 3 H]ethanolamine-labeled peptides. Three peptides were sequenced and were identical to two distinct regions of the human EF-1 alpha protein. Blank sequencing cycles coinciding with glutamic acid in the human cDNA-derived sequence were also found to release [ 3 H]ethanolamine, and compositional analysis of these peptides confirmed the presence of glutamic acid. Dansylation analysis demonstrates that the amine group of the ethanolamine is blocked. These results indicate that EF-1 alpha is posttranslationally modified by the covalent attachment of ethanolamine via an amide bond to at least two specific glutamic acid residues (Glu-301 and Glu-374). The hydroxyl group of the attached ethanolamine was shown by mass spectrometry and compositional analysis, to be further modified by the addition of a phosphoglycerol unit. This novel posttranslational modification may represent an important alteration of EF-1 alpha, comparable to the regulatory effects of posttranslational methylation of EF-1 alpha lysine residues

  14. Tracking the behavior of Maillard browning in lysine/arginine-sugar model systems under high hydrostatic pressure.

    Science.gov (United States)

    Ma, Xiao-Juan; Gao, Jin-Yan; Tong, Ping; Li, Xin; Chen, Hong-Bing

    2017-12-01

    High-pressure processing is gaining popularity in the food industry. However, its effect on the Maillard reaction during high-pressure-assisted pasteurization and sterilization is not well documented. This study aimed to investigate the effects of high hydrostatic pressure on the Maillard reaction during these processes using amino acid (lysine or arginine)-sugar (glucose or fructose) solution models. High pressure retarded the intermediate and final stages of the Maillard reaction in the lysine-sugar model. For the lysine-glucose model, the degradation rate of Amadori compounds was decelerated, while acceleration was observed in the arginine-sugar model. Increased temperature not only accelerated the Maillard reaction over time but also formed fluorescent compounds with different emission wavelengths. Lysine reacted with the sugars more readily than arginine under the same conditions. In addition, it was easier for lysine to react with glucose, whereas arginine reacted more readily with fructose under high pressure. High pressure exerts different effects on lysine-sugar and arginine-sugar models. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  15. Sensitive radioimmunoassay for plasma arginine vasopressin

    International Nuclear Information System (INIS)

    Thibonnier, M.; Soto, M.E.; Corvol, P.; Milliez, P.; Marchetti, J.; Menard, J.

    1980-01-01

    Using an ion exchange resin, a sensitive radioimmunoassay for plasma arginine vasopressin (AVP) was developed. This assay was characterized by the absence of blank values, an excellent recovery rate, great sensitivity (0.1 pg of AVP was significantly detected) and reproducibility. In 8 normal men, plasma AVP after overnight dehydration was 1.57+-0.17 pg/ml, and dropped to 0.58+-0.11 pg/ml after 20 ml/kg oral water loading. Significant correlations between plasma AVP levels and plasma or urinary osmolality confirm the validity of this assay. In complete pituitary diabetes insipidus (n=4) plasma AVP was undetectable whereas it was frankly increased in Schwartz-Bartter syndrome (3 to 33 pg/ml, n=8) [fr

  16. Arginine and Polyamines Fate in Leishmania Infection

    Science.gov (United States)

    Muxel, Sandra M.; Aoki, Juliana I.; Fernandes, Juliane C. R.; Laranjeira-Silva, Maria F.; Zampieri, Ricardo A.; Acuña, Stephanie M.; Müller, Karl E.; Vanderlinde, Rubia H.; Floeter-Winter, Lucile M.

    2018-01-01

    Leishmania is a protozoan parasite that alternates its life cycle between the sand fly and the mammalian host macrophages, involving several environmental changes. The parasite responds to these changes by promoting a rapid metabolic adaptation through cellular signaling modifications that lead to transcriptional and post-transcriptional gene expression regulation and morphological modifications. Molecular approaches such as gene expression regulation, next-generation sequencing (NGS), microRNA (miRNA) expression profiling, in cell Western blot analyses and enzymatic activity profiling, have been used to characterize the infection of murine BALB/c and C57BL/6 macrophages, as well as the human monocytic cell-lineage THP-1, with Leishmania amazonensis wild type (La-WT) or arginase knockout (La-arg-). These models are being used to elucidate physiological roles of arginine and polyamines pathways and the importance of arginase for the establishment of the infection. In this review, we will describe the main aspects of Leishmania-host interaction, focusing on the arginine and polyamines pathways and pointing to possible targets to be used for prognosis and/or in the control of the infection. The parasite enzymes, arginase and nitric oxide synthase-like, have essential roles in the parasite survival and in the maintenance of infection. On the other hand, in mammalian macrophages, defense mechanisms are activated inducing alterations in the mRNA, miRNA and enzymatic profiles that lead to the control of infection. Furthermore, the genetic background of both parasite and host are also important to define the fate of infection. PMID:29379478

  17. Asymmetric Dimethyl Arginine in Hypothyroid Patients

    International Nuclear Information System (INIS)

    Abdel-Messeih, P.L.

    2012-01-01

    Thyroid diseases may lead to endothelial dysfunction, however, the mechanism underlying the endothelial dysfunction in thyroid disease is still not clear. Asymmetric dimethyl arginine (ADMA), a novel inhibitor of endothelial nitric oxide synthetase (eNOS), was reported to inhibit nitric oxide (NO) synthesis from L-arginine. The present study was carried out to investigate ADMA levels together with effects of dislipidemia in sub-clinical and overt hypothyroid females. There were significant increase in the levels of total cholesterol, low density lipoprotein-cholesterol (LDL-c), high density lipoprotein-cholesterol (HDL-c), thyroid stimulating hormone (TSH) and ADMA in hypothyroid females as compared to controls while the levels of NO and free T 4 were significantly decreased than controls. Sub-clinical hypothyroid females had significant high TSH, LDL-c and non-significantly high ADMA levels and total cholesterol as compared to controls while they had significant decrease in NO, HDL-c and non-significant decrease in free T 4 as compared to controls. There were significant negative correlations between NO and both ADMA (r 2 = 0.84) and free T 4 (r 2 = 0.95) in overt hypothyroid group while significant positive correlation (r 2 = 0.85) was detected between TSH and HDL-c in the same group. These results are highly suggestive that the decrease of nitric oxide secondary to accumulation of ADMA represent an important pathogenic factor together with dyslipidemia in endothelial dysfunction and increased cardiovascular risk especially in hypothyroid females

  18. Asymmetric Dimethyl Arginine in Hypothyroid Patients

    Energy Technology Data Exchange (ETDEWEB)

    Abdel-Messeih, P. L. [Health Radiation Research Department, National Centre for Radiation Research and Technology, Cairo (Egypt)

    2012-07-01

    Thyroid diseases may lead to endothelial dysfunction, however, the mechanism underlying the endothelial dysfunction in thyroid disease is still not clear. Asymmetric dimethyl arginine (ADMA), a novel inhibitor of endothelial nitric oxide synthetase (eNOS), was reported to inhibit nitric oxide (NO) synthesis from L-arginine. The present study was carried out to investigate ADMA levels together with effects of dislipidemia in sub-clinical and overt hypothyroid females. There were significant increase in the levels of total cholesterol, low density lipoprotein-cholesterol (LDL-c), high density lipoprotein-cholesterol (HDL-c), thyroid stimulating hormone (TSH) and ADMA in hypothyroid females as compared to controls while the levels of NO and free T{sub 4} were significantly decreased than controls. Sub-clinical hypothyroid females had significant high TSH, LDL-c and non-significantly high ADMA levels and total cholesterol as compared to controls while they had significant decrease in NO, HDL-c and non-significant decrease in free T{sub 4} as compared to controls. There were significant negative correlations between NO and both ADMA (r{sup 2} = 0.84) and free T{sub 4} (r{sup 2} = 0.95) in overt hypothyroid group while significant positive correlation (r{sup 2} = 0.85) was detected between TSH and HDL-c in the same group. These results are highly suggestive that the decrease of nitric oxide secondary to accumulation of ADMA represent an important pathogenic factor together with dyslipidemia in endothelial dysfunction and increased cardiovascular risk especially in hypothyroid females.

  19. Bio energy production in birch and hybrid aspen after addition of residue based fertilizers - establishment of fertilization trials; Bioenergiproduktion hos bjoerk och hybridasp vid tillfoersel av restproduktbaserade goedselmedel - etablering av goedslingsfoersoek

    Energy Technology Data Exchange (ETDEWEB)

    Thelin, Gunnar (EkoBalans Fenix AB, Malmoe (Sweden))

    2009-03-15

    Sewage sludge and wood ashes could be used as fertilizers in order to increase forest tree production. In southern Sweden forest growth normally increases with approximately 10 % after ash recycling due to increased N and/or P availability. P is added with the ashes and the pH-increasing effect of the wood ash can lead to increased N net mineralization. Other positive effects of wood ash recycling are improved nutrient sustainability and less acid run-off water. Possible negative effects are heavy metal accumulation, if the content of one or more heavy metals of the recycled ash exceeds the heavy metal content of the harvested biomass, and nitrate leaching if the vegetation cannot take up nitrified N. It is important to evaluate the sustainability of fertilization systems based on residues such as sludge and wood ash. Wood ash does not contain N and the P concentration often is too low for the ashes to function as an NP fertilizer. Thus N and sometimes P must be added. Sludge is an interesting alternative. The main purpose of the project is to study sustainable production of forest bio energy in intensively cultivated birch and hybrid aspen stands. Another purpose is to establish experiments that can be used for long term studies and as demonstration objects. In the first few years the goal is to study the short term effects of residue based fertilization compared to conventional NPK fertilization on tree nutrient uptake, nutrient leaching, sustainability and economy. In the long term the goal is to design appropriate fertilization strategies in a residue based fertilization system for the intensive cultivation of birch and hybrid aspen without negative side effects such as large scale nutrient leaching. Four field experiments were established in 2008 and one additional experiment in hybrid aspen will be established in the spring of 2009. Elevated bud N and P concentrations after fertilization with both Ashes+N and NPK means good possibilities for future growth

  20. Residual stresses

    International Nuclear Information System (INIS)

    Sahotra, I.M.

    2006-01-01

    The principal effect of unloading a material strained into the plastic range is to create a permanent set (plastic deformation), which if restricted somehow, gives rise to a system of self-balancing within the same member or reaction balanced by other members of the structure., known as residual stresses. These stresses stay there as locked-in stresses, in the body or a part of it in the absence of any external loading. Residual stresses are induced during hot-rolling and welding differential cooling, cold-forming and extruding: cold straightening and spot heating, fabrication and forced fitting of components constraining the structure to a particular geometry. The areas which cool more quickly develop residual compressive stresses, while the slower cooling areas develop residual tensile stresses, and a self-balancing or reaction balanced system of residual stresses is formed. The phenomenon of residual stresses is the most challenging in its application in surface modification techniques determining endurance mechanism against fracture and fatigue failures. This paper discusses the mechanism of residual stresses, that how the residual stresses are fanned and what their behavior is under the action of external forces. Such as in the case of a circular bar under limit torque, rectangular beam under limt moment, reclaiming of shafts welds and peening etc. (author)

  1. Identification of a novel antimicrobial peptide from human hepatitis B virus core protein arginine-rich domain (ARD.

    Directory of Open Access Journals (Sweden)

    Heng-Li Chen

    Full Text Available The rise of multidrug-resistant (MDR pathogens causes an increasing challenge to public health. Antimicrobial peptides are considered a possible solution to this problem. HBV core protein (HBc contains an arginine-rich domain (ARD at its C-terminus, which consists of 16 arginine residues separated into four clusters (ARD I to IV. In this study, we demonstrated that the peptide containing the full-length ARD I-IV (HBc147-183 has a broad-spectrum antimicrobial activity at micro-molar concentrations, including some MDR and colistin (polymyxin E-resistant Acinetobacter baumannii. Furthermore, confocal fluorescence microscopy and SYTOX Green uptake assay indicated that this peptide killed Gram-negative and Gram-positive bacteria by membrane permeabilization or DNA binding. In addition, peptide ARD II-IV (HBc153-176 and ARD I-III (HBc147-167 were found to be necessary and sufficient for the activity against P. aeruginosa and K. peumoniae. The antimicrobial activity of HBc ARD peptides can be attenuated by the addition of LPS. HBc ARD peptide was shown to be capable of direct binding to the Lipid A of lipopolysaccharide (LPS in several in vitro binding assays. Peptide ARD I-IV (HBc147-183 had no detectable cytotoxicity in various tissue culture systems and a mouse animal model. In the mouse model by intraperitoneal (i.p. inoculation with Staphylococcus aureus, timely treatment by i.p. injection with ARD peptide resulted in 100-fold reduction of bacteria load in blood, liver and spleen, as well as 100% protection of inoculated animals from death. If peptide was injected when bacterial load in the blood reached its peak, the protection rate dropped to 40%. Similar results were observed in K. peumoniae using an IVIS imaging system. The finding of anti-microbial HBc ARD is discussed in the context of commensal gut microbiota, development of intrahepatic anti-viral immunity and establishment of chronic infection with HBV. Our current results suggested that

  2. Biosynthesis of agmatine in isolated mitochondria and perfused rat liver: studies with 15N-labelled arginine

    Science.gov (United States)

    2005-01-01

    An important but unresolved question is whether mammalian mitochondria metabolize arginine to agmatine by the ADC (arginine decarboxylase) reaction. 15N-labelled arginine was used as a precursor to address this question and to determine the flux through the ADC reaction in isolated mitochondria obtained from rat liver. In addition, liver perfusion system was used to examine a possible action of insulin, glucagon or cAMP on a flux through the ADC reaction. In mitochondria and liver perfusion, 15N-labelled agmatine was generated from external 15N-labelled arginine. The production of 15N-labelled agmatine was time- and dose-dependent. The time-course of [U-15N4]agmatine formation from 2 mM [U-15N4]arginine was best fitted to a one-phase exponential curve with a production rate of approx. 29 pmol·min−1·(mg of protein)−1. Experiments with an increasing concentration (0– 40 mM) of [guanidino-15N2]arginine showed a Michaelis constant Km for arginine of 46 mM and a Vmax of 3.7 nmol·min−1·(mg of protein)−1 for flux through the ADC reaction. Experiments with broken mitochondria showed little changes in Vmax or Km values, suggesting that mitochondrial arginine uptake had little effect on the observed Vmax or Km values. Experiments with liver perfusion demonstrated that over 95% of the effluent agmatine was derived from perfusate [guanidino-15N2]arginine regardless of the experimental condition. However, the output of 15N-labelled agmatine (nmol·min−1·g−1) increased by approx. 2-fold (P<0.05) in perfusions with cAMP. The findings of the present study provide compelling evidence that mitochondrial ADC is present in the rat liver, and suggest that cAMP may stimulate flux through this pathway. PMID:15656789

  3. Effect of Polyhydroxybutyrate (PHB) storage on L-arginine production in recombinant Corynebacterium crenatum using coenzyme regulation.

    Science.gov (United States)

    Xu, Meijuan; Qin, Jingru; Rao, Zhiming; You, Hengyi; Zhang, Xian; Yang, Taowei; Wang, Xiaoyuan; Xu, Zhenghong

    2016-01-19

    Corynebacterium crenatum SYPA 5 is the industrial strain for L-arginine production. Poly-β-hydroxybutyrate (PHB) is a kind of biopolymer stored as bacterial reserve materials for carbon and energy. The introduction of the PHB synthesis pathway into several strains can regulate the global metabolic pathway. In addition, both the pathways of PHB and L-arginine biosynthesis in the cells are NADPH-dependent. NAD kinase could upregulate the NADPH concentration in the bacteria. Thus, it is interesting to investigate how both PHB and NAD kinase affect the L-arginine biosynthesis in C. crenatum SYPA 5. C. crenatum P1 containing PHB synthesis pathway was constructed and cultivated in batch fermentation for 96 h. The enzyme activities of the key enzymes were enhanced comparing to the control strain C. crenatum SYPA 5. More PHB was found in C. crenatum P1, up to 12.7 % of the dry cell weight. Higher growth level and enhanced glucose consumptions were also observed in C. crenatum P1. With respect to the yield of L-arginine, it was 38.54 ± 0.81 g/L, increasing by 20.6 %, comparing to the control under the influence of PHB accumulation. For more NADPH supply, C. crenatum P2 was constructed with overexpression of NAD kinase based on C. crenatum P1. The NADPH concentration was increased in C. crenatum P2 comparing to the control. PHB content reached 15.7 % and 41.11 ± 1.21 g/L L-arginine was obtained in C. crenatum P2, increased by 28.6 %. The transcription levels of key L-arginine synthesis genes, argB, argC, argD and argJ in recombinant C. crenatum increased 1.9-3.0 times compared with the parent strain. Accumulation of PHB by introducing PHB synthesis pathway, together with up-regulation of coenzyme level by overexpressing NAD kinase, enables the recombinant C. crenatum to serve as high-efficiency cell factories in the long-time L-arginine fermentation. Furthermore, batch cultivation of the engineered C. crenatum revealed that it could accumulate both extracellular L-arginine

  4. EG-01EPIGENETIC INACTIVATION OF ARGININE BIOSYNTHESIS PATHWAY IN PAEDIATRIC HIGH GRADE GLIOMA

    Science.gov (United States)

    Channathodiyil, Prasanna; Kardooni, Hoda; Khozoie, Combiz; Nelofer, Syed; Darling, John; Morris, Mark; Warr, Tracy

    2014-01-01

    Aberrant cellular metabolism contributes significantly to the growth and proliferation of several tumour types. Identification of genes that control critical metabolic pathways is a major factor in the development of novel therapies that target metabolic defects in tumour cells. Our aim is to identify such genes in paediatric high grade glioma that are altered due to promoter hyper-methylation of cytosine residues in CpG dinucleotides. Genome wide DNA methylation profiling using Illumina infinium methylation 450K bead chip array was performed on 18 well-characterised short term cultures derived from paediatric high grade astrocytoma including 3 from diffuse intrinsic pontine glioma. Data analyses were based on beta scores of probes for each gene as measures of intensities of methylation. Genes were selected with beta scores of tumour > =0.70 and that of normal human astrocytes < =0.30. We identified that two vital genes involved in the regulation of arginine biosynthetic pathway, argininosuccinate synthetase 1(ASS1) and argininosuccinate lyase (ASL) were methylated in 9/18 (50%) cases. Hyper methylation was confirmed by methylation-specific PCR and up-regulation of gene expression following treatment with 2 µM 5-aza-2'-deoxyctidine. Down-regulation of ASS1 in hyper methylated samples was confirmed by Western blot analysis. Our findings report epigenetic deregulation of ASS1 and ASL in a subset of paediatric high grade glioma. The enzymes encoded by these genes are essential elements of urea cycle that function together in the de novo synthesis of arginine from citrulline. Tumour cells with deficient ASS1/ASL depend on external sources of arginine for survival and have been reported to be sensitive to autophagic cell death induced by arginine starvation. Therefore, further investigation may render the possibility of arginine-deprivation therapy in such sub type of paediatric high grade glioma. This therapeutic approach is of interest as tumour cells with abnormal

  5. [Effect of L-arginine on platelet aggregation, endothelial function adn exercise tolerance in patients with stable angina pectoris].

    Science.gov (United States)

    Sozykin, A V; Noeva, E A; Balakhonova, T V; Pogorelova, O A; Men'shikov, M Iu

    2000-01-01

    Examination of the action of donor NO (L-arginine) on platelet aggregation, endothelial function and exercise tolerance in patients with stable angina of effort (SAE). 42 patients with SAE (functional class I-II) and 10 healthy volunteers (control group) were assigned to two groups. 22 patients of group 1 were randomized to cross-over. They received cardiket (60 mg/day for 10 days or cardiket (60 mg/day) in combination with L-arginine (15 g/day for 10 days). 20 SAE patients of group 2 and control group received L-arginine (15 g/day for 10 days). In each group blood lipids were examined, and bicycle exercise test (BET) was performed. In addition, platelet aggregation and endothelial function were studied in group 2 and control group before and after the course of L-arginine. Compared to control group, endothelial function significantly improved in group 2 (from 5.0 +/- 2.9 to 7.8 +/- 4.1% vs 7.1 +/- 1.9 to 6.6 +/- 4.8%) (M +/- SD). BET duration increased in all the patients. After ADP addition in concentrations 1.5, 2.0, and 5.0 micromol/l platelet aggregation declined in 17 patients except 3 in whom the aggregation remained unchanged. Positive effect of L-arginine on endothelial function, exercise tolerance and platelet aggregation was observed in patients with stable angina of effort (functional class I-II). Therefore, arginine can be recommended as an adjuvant in the treatment of patients with ischemic heart disease.

  6. Residual stresses

    International Nuclear Information System (INIS)

    Macherauch, E.

    1978-01-01

    Residual stresses are stresses which exist in a material without the influence of external powers and moments. They come into existence when the volume of a material constantly changes its form as a consequence of mechanical, thermal, and/or chemical processes and is hindered by neighbouring volumes. Bodies with residual stress are in mechanical balance. These residual stresses can be manifested by means of all mechanical interventions disturbing this balance. Acoustical, optical, radiological, and magnetical methods involving material changes caused by residual stress can also serve for determining residual stress. Residual stresses have an ambivalent character. In technical practice, they are feared and liked at the same time. They cause trouble because they can be the cause for unexpected behaviour of construction elements. They are feared since they can cause failure, in the worst case with catastrophical consequences. They are appreciated, on the other hand, because, in many cases, they can contribute to improvements of the material behaviour under certain circumstances. But they are especially liked for their giving convenient and (this is most important) mostly uncontrollable explanations. For only in very few cases we have enough knowledge and possibilities for the objective evaluation of residual stresses. (orig.) [de

  7. A cyanase is transcriptionally regulated by arginine and involved in cyanate decomposition in Sordaria macrospora.

    Science.gov (United States)

    Elleuche, Skander; Pöggeler, Stefanie

    2008-11-01

    Cyanase degrades toxic cyanate to NH3 and CO2 in a bicarbonate-dependent reaction. High concentrations of cyanate are fairly toxic to organisms. Here, we characterize a eukaryotic cyanase for the first time. We have isolated the cyn1 gene encoding a cyanase from the filamentous ascomycete Sordaria macrospora and functionally characterized the cyn1 product after heterologous expression in Escherichia coli. Site-directed mutagenesis confirmed a predicted catalytic centre of three conserved amino-acids. A Deltacyn1 knockout in S. macrospora was totally devoid of cyanase activity and showed an increased sensitivity to exogenously supplied cyanate in an arginine-depleted medium, defects in ascospore germination, but no other obvious morphological phenotype. By means of real-time PCR we have demonstrated that the transcriptional level of cyn1 is markedly elevated in the presence of cyanate and down-regulated by addition of arginine. The putative functions of cyanase in fungi are discussed.

  8. N-hydroxylamine is not an intermediate in the conversion of L-arginine to an activator of soluble guanylate cyclase in neuroblastoma N1E-115 cells.

    Science.gov (United States)

    Pou, S; Pou, W S; Rosen, G M; el-Fakahany, E E

    1991-01-01

    This study evaluates the role of N-hydroxylamine (NH2OH) in activating soluble guanylate cyclase in the mouse neuroblastoma clone N1E-115. It has been proposed that NH2OH is a putative intermediate in the biochemical pathway for the generation of nitric oxide (NO)/endothelium-derived relaxing factor (EDRF) from L-arginine. NH2OH caused a time- and concentration-dependent increase in cyclic GMP formation in intact cells. This response was not dependent on Ca2+. In cytosol preparations the activation of guanylate cyclase by L-arginine was dose-dependent and required Ca2+ and NADPH. In contrast, NH2OH itself did not activate cytosolic guanylate cyclase but it inhibited the basal activity of this enzyme in a concentration-dependent manner. The formation of cyclic GMP in the cytosolic fractions in response to NH2OH required the addition of catalase and H2O2. On the other hand, catalase and/or H2O2 lead to a decrease in L-arginine-induced cyclic GMP formation. Furthermore, NH2OH inhibited L-arginine- and sodium nitroprusside-induced cyclic GMP formation in the cytosol. The inhibition of L-arginine-induced cyclic GMP formation in the cytosol by NH2OH was not reversed by the addition of superoxide dismutase. These data strongly suggest that NH2OH is not a putative intermediate in the metabolism of L-arginine to an activator of guanylate cyclase. PMID:1671745

  9. Endoplasmic reticulum protein targeting of phospholamban: a common role for an N-terminal di-arginine motif in ER retention?

    Directory of Open Access Journals (Sweden)

    Parveen Sharma

    2010-07-01

    Full Text Available Phospholamban (PLN is an effective inhibitor of the sarco(endoplasmic reticulum Ca(2+-ATPase, which transports Ca(2+ into the SR lumen, leading to muscle relaxation. A mutation of PLN in which one of the di-arginine residues at positions 13 and 14 was deleted led to a severe, early onset dilated cardiomyopathy. Here we were interested in determining the cellular mechanisms involved in this disease-causing mutation.Mutations deleting codons for either or both Arg13 or Arg14 resulted in the mislocalization of PLN from the ER. Our data show that PLN is recycled via the retrograde Golgi to ER membrane traffic pathway involving COP-I vesicles, since co-immunoprecipitation assays determined that COP I interactions are dependent on an intact di-arginine motif as PLN RDelta14 did not co-precipitate with COP I containing vesicles. Bioinformatic analysis determined that the di-arginine motif is present in the first 25 residues in a large number of all ER/SR Gene Ontology (GO annotated proteins. Mutations in the di-arginine motif of the Sigma 1-type opioid receptor, the beta-subunit of the signal recognition particle receptor, and Sterol-O-acyltransferase, three proteins identified in our bioinformatic screen also caused mislocalization of these known ER-resident proteins.We conclude that PLN is enriched in the ER due to COP I-mediated transport that is dependent on its intact di-arginine motif and that the N-terminal di-arginine motif may act as a general ER retrieval sequence.

  10. Mitochondrial dysfunction in brain cortex mitochondria of STZ-diabetic rats: effect of l-Arginine.

    Science.gov (United States)

    Ortiz, M Del Carmen; Lores-Arnaiz, Silvia; Albertoni Borghese, M Florencia; Balonga, Sabrina; Lavagna, Agustina; Filipuzzi, Ana Laura; Cicerchia, Daniela; Majowicz, Monica; Bustamante, Juanita

    2013-12-01

    Mitochondrial dysfunction has been implicated in many diseases, including diabetes. It is well known that oxygen free radical species are produced endogenously by mitochondria, and also nitric oxide (NO) by nitric oxide synthases (NOS) associated to mitochondrial membranes, in consequence these organelles constitute main targets for oxidative damage. The aim of this study was to analyze mitochondrial physiology and NO production in brain cortex mitochondria of streptozotocin (STZ) diabetic rats in an early stage of diabetes and the potential effect of L-arginine administration. The diabetic condition was characterized by a clear hyperglycaemic state with loose of body weight after 4 days of STZ injection. This hyperglycaemic state was associated with mitochondrial dysfunction that was evident by an impairment of the respiratory activity, increased production of superoxide anion and a clear mitochondrial depolarization. In addition, the alteration in mitochondrial physiology was associated with a significant decrease in both NO production and nitric oxide synthase type I (NOS I) expression associated to the mitochondrial membranes. An increased level of thiobarbituric acid-reactive substances (TBARS) in brain cortex homogenates from STZ-diabetic rats indicated the presence of lipid peroxidation. L-arginine treatment to diabetic rats did not change blood glucose levels but significantly ameliorated the oxidative stress evidenced by lower TBARS and a lower level of superoxide anion. This effect was paralleled by improvement of mitochondrial respiratory function and a partial mitochondrial repolarization.In addition, the administration of L-arginine to diabetic rats prevented the decrease in NO production and NOSI expression. These results could indicate that exogenously administered L-arginine may have beneficial effects on mitochondrial function, oxidative stress and NO production in brain cortex mitochondria of STZ-diabetic rats.

  11. Facilitation of peptide fibre formation by arginine-phosphate ...

    Indian Academy of Sciences (India)

    WINTEC

    Peptide; self-assembly; arginine; microscopy. ... The latter property, in particular, observed in .... this process repeated till the gummy compound be- ..... micrograph of Congo red-stained image of individual peptide fibre from aged solution of 4.

  12. An Arginine Finger Regulates the Sequential Action of Asymmetrical Hexameric ATPase in the Double-Stranded DNA Translocation Motor.

    Science.gov (United States)

    Zhao, Zhengyi; De-Donatis, Gian Marco; Schwartz, Chad; Fang, Huaming; Li, Jingyuan; Guo, Peixuan

    2016-10-01

    Biological motors are ubiquitous in living systems. Currently, how the motor components coordinate the unidirectional motion is elusive in most cases. Here, we report that the sequential action of the ATPase ring in the DNA packaging motor of bacteriophage ϕ29 is regulated by an arginine finger that extends from one ATPase subunit to the adjacent unit to promote noncovalent dimer formation. Mutation of the arginine finger resulted in the interruption of ATPase oligomerization, ATP binding/hydrolysis, and DNA translocation. Dimer formation reappeared when arginine mutants were mixed with other ATPase subunits that can offer the arginine to promote their interaction. Ultracentrifugation and virion assembly assays indicated that the ATPase was presenting as monomers and dimer mixtures. The isolated dimer alone was inactive in DNA translocation, but the addition of monomer could restore the activity, suggesting that the hexameric ATPase ring contained both dimer and monomers. Moreover, ATP binding or hydrolysis resulted in conformation and entropy changes of the ATPase with high or low DNA affinity. Taking these observations together, we concluded that the arginine finger regulates sequential action of the motor ATPase subunit by promoting the formation of the dimer inside the hexamer. The finding of asymmetrical hexameric organization is supported by structural evidence of many other ATPase systems showing the presence of one noncovalent dimer and four monomer subunits. All of these provide clues for why the asymmetrical hexameric ATPase gp16 of ϕ29 was previously reported as a pentameric configuration by cryo-electron microscopy (cryo-EM) since the contact by the arginine finger renders two adjacent ATPase subunits closer than other subunits. Thus, the asymmetrical hexamer would appear as a pentamer by cryo-EM, a technology that acquires the average of many images. Copyright © 2016 Zhao et al.

  13. Roles of conserved arginines in ATP-binding domains of AAA+ chaperone ClpB from Thermus thermophilus.

    Science.gov (United States)

    Yamasaki, Takashi; Nakazaki, Yosuke; Yoshida, Masasuke; Watanabe, Yo-hei

    2011-07-01

    ClpB, a member of the expanded superfamily of ATPases associated with diverse cellular activities (AAA+), forms a ring-shaped hexamer and cooperates with the DnaK chaperone system to reactivate aggregated proteins in an ATP-dependent manner. The ClpB protomer consists of an N-terminal domain, an AAA+ module (AAA-1), a middle domain, and a second AAA+ module (AAA-2). Each AAA+ module contains highly conserved WalkerA and WalkerB motifs, and two arginines (AAA-1) or one arginine (AAA-2). Here, we investigated the roles of these arginines (Arg322, Arg323, and Arg747) of ClpB from Thermus thermophilus in the ATPase cycle and chaperone function by alanine substitution. These mutations did not affect nucleotide binding, but did inhibit the hydrolysis of the bound ATP and slow the threading of the denatured protein through the central pore of the T. thermophilus ClpB ring, which severely impaired the chaperone functions. Previously, it was demonstrated that ATP binding to the AAA-1 module induced motion of the middle domain and stabilized the ClpB hexamer. However, the arginine mutations of the AAA-1 module destabilized the ClpB hexamer, even though ATP-induced motion of the middle domain was not affected. These results indicated that the three arginines are crucial for ATP hydrolysis and chaperone activity, but not for ATP binding. In addition, the two arginines in AAA-1 and the ATP-induced motion of the middle domain independently contribute to the stabilization of the hexamer. © 2011 The Authors Journal compilation © 2011 FEBS.

  14. Acellular matrix of bovine pericardium bound with L-arginine

    International Nuclear Information System (INIS)

    Kim, Hyo Joo; Bae, Jin Woo; Kim, Chun Ho; Lee, Jin Woo; Shin, Jung Woog; Park, Ki Dong

    2007-01-01

    Surface immobilization of bioactive molecules onto natural tissues has been interestingly studied for the development of new functional matrices for the replacement of lost or malfunctioning tissues. In this study, an acellular matrix of bovine pericardium (ABP) was chemically modified by the direct coupling of L-arginine after glutaraldehyde (GA) cross-linking. The effects of L-arginine coupling on durability and calcification were investigated and the biocompatibility was evaluated in vitro and in vivo. A four-step detergent and enzymatic extraction process has been utilized to remove cellular components from fresh bovine pericardium (BP). Microscopic observation confirmed that nearly all cellular constituents are removed. Thermal and mechanical properties showed that the durability of L-arginine-treated matrices increased as compared with control ABP and GA-treated ABP. Resistance to collagenase digestion revealed that modified matrices have greater resistance to enzyme digestion than control ABP and GA-treated ABP. The in vivo calcification study demonstrated much less calcium deposition on L-arginine-treated ABP than GA-treated one. In vitro cell viability results showed that ABP modified with L-arginine leads to a significant increase in attachment of human dermal fibroblasts. The obtained results attest to the usefulness of L-arginine-treated ABP matrices for cardiovascular bioprostheses

  15. Acellular matrix of bovine pericardium bound with L-arginine

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyo Joo [Department of Molecular Science and Technology, Ajou University, Suwon 443-749 (Korea, Republic of); Bae, Jin Woo [Department of Molecular Science and Technology, Ajou University, Suwon 443-749 (Korea, Republic of); Kim, Chun Ho [Laboratory of Tissue Engineering, Korea Cancer Center Hospital, Seoul 139-240 (Korea, Republic of); Lee, Jin Woo [Department of Orthopaedic Surgery, College of Medicine, Yonsei University, Seoul 120-749 (Korea, Republic of); Shin, Jung Woog [Department of Biomedical Engineering, Inje University, Gimhae 621-749 (Korea, Republic of); Park, Ki Dong [Department of Molecular Science and Technology, Ajou University, Suwon 443-749 (Korea, Republic of)

    2007-09-15

    Surface immobilization of bioactive molecules onto natural tissues has been interestingly studied for the development of new functional matrices for the replacement of lost or malfunctioning tissues. In this study, an acellular matrix of bovine pericardium (ABP) was chemically modified by the direct coupling of L-arginine after glutaraldehyde (GA) cross-linking. The effects of L-arginine coupling on durability and calcification were investigated and the biocompatibility was evaluated in vitro and in vivo. A four-step detergent and enzymatic extraction process has been utilized to remove cellular components from fresh bovine pericardium (BP). Microscopic observation confirmed that nearly all cellular constituents are removed. Thermal and mechanical properties showed that the durability of L-arginine-treated matrices increased as compared with control ABP and GA-treated ABP. Resistance to collagenase digestion revealed that modified matrices have greater resistance to enzyme digestion than control ABP and GA-treated ABP. The in vivo calcification study demonstrated much less calcium deposition on L-arginine-treated ABP than GA-treated one. In vitro cell viability results showed that ABP modified with L-arginine leads to a significant increase in attachment of human dermal fibroblasts. The obtained results attest to the usefulness of L-arginine-treated ABP matrices for cardiovascular bioprostheses.

  16. Radioimmunoassay of arginine vasopressin in human plasma

    International Nuclear Information System (INIS)

    Uhlich, E.; Weber, P.; Groeschel-Stewart, U.; Roeschlau, T.; Wuerzburg Univ.

    1975-01-01

    Antibodies for the radioimmunoassay of arginine vasopressin (AVP) described here were produced in rabbits using synthetic AVP coupled to rabbit γ-globulin with carbodiimide. In three out of six rabbits, significant antibody titres were obtained. Using the best antisera produced, 40% of labelled AVP was bound at a final dilution of 1 : 50,000. After iodination of synthetic AVP with 125 I using the chloramin-T method, a gel filtration on Sephadex G-25 was performed to purify the iodinated AVP. For separation of antibody bound and free hormone, a second antibody precipitation was used. There was no crossreactivity with oxytocin. AVP was extracted from plasma after ammoniumsulfate precipitation of the proteins by adsorption to Florisil. The recovery of AVP added to plasma in amounts of 5-25 pg/ml was 60 +- 15% (n = 6). The minimum amount of AVP detectable was 1 pg per ml plasma. The plasma level in normal adults under standard conditions was 3.4 +- 2.2 pg/ml. This is in agreement with data recently published by other researchers. The applicability and reproducibility was further tested in measurements of samples taken hourly during the entire day under water diuresis and after hormonal stimulation of AVP. (orig.) [de

  17. Hot Melt Extrusion and Spray Drying of Co-amorphous Indomethacin-Arginine With Polymers.

    Science.gov (United States)

    Lenz, Elisabeth; Löbmann, Korbinian; Rades, Thomas; Knop, Klaus; Kleinebudde, Peter

    2017-01-01

    Co-amorphous drug-amino acid systems have gained growing interest as an alternative to common amorphous formulations which contain polymers as stabilizers. Several preparation methods have recently been investigated, including vibrational ball milling on a laboratory scale or spray drying in a larger scale. In this study, the feasibility of hot melt extrusion for continuous manufacturing of co-amorphous drug-amino acid formulations was examined, challenging the fact that amino acids melt with degradation at high temperatures. Furthermore, the need for an addition of a polymer in this process was evaluated. After a polymer screening via the solvent evaporation method, co-amorphous indomethacin-arginine was prepared by a melting-solvent extrusion process without and with copovidone. The obtained products were characterized with respect to their solid-state properties, non-sink dissolution behavior, and stability. Results were compared to those of spray-dried formulations with the same compositions and to spray-dried indomethacin-copovidone. Overall, stable co-amorphous systems could be prepared by extrusion without or with copovidone, which exhibited comparable molecular interaction properties to the respective spray-dried products, while phase separation was detected by differential scanning calorimetry in several cases. The formulations containing indomethacin in combination with arginine and copovidone showed enhanced dissolution behavior over the formulations with only copovidone or arginine. Copyright © 2016 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

  18. Persistence of TEL-AML1 fusion gene as minimal residual disease has no additive prognostic value in CD 10 positive B-acute lymphoblastic leukemia: a FISH study

    Directory of Open Access Journals (Sweden)

    Ezz-Eldin Azza M

    2008-10-01

    Full Text Available Abstract Objectives We have analyzed t(12;21(p13:q22 in an attempt to evaluate the frequency and prognostic significance of TEL-AML1 fusion gene in patients with childhood CD 10 positive B-ALL by fluorescence in situ hybridization (FISH. Also, we have monitored the prognostic value of this gene as a minimal residual disease (MRD. Methods All bone marrow samples of eighty patients diagnosed as CD 10 positive B-ALL in South Egypt Cancer Institute were evaluated by fluorescence in situ hybridization (FISH for t(12;21 in newly diagnosed cases and after morphological complete remission as a minimal residual disease (MRD. We determined the prognostic significance of TEL-AML1 fusion represented by disease course and survival. Results TEL-AML1 fusion gene was positive in (37.5% in newly diagnosed patients. There was a significant correlation between TEL-AML1 fusion gene both at diagnosis (r = 0.5, P = 0.003 and as a MRD (r = 0.4, P = 0.01 with favorable course. Kaplan-Meier curve for the presence of TEL-AML1 fusion at the diagnosis was associated with a better probability of overall survival (OS; mean survival time was 47 ± 1 month, in contrast to 28 ± 5 month in its absence (P = 0.006. Also, the persistence at TEL-AML1 fusion as a MRD was not significantly associated with a better probability of OS; the mean survival time was 42 ± 2 months in the presence of MRD and it was 40 ± 1 months in its absence. So, persistence of TEL-AML1 fusion as a MRD had no additive prognostic value over its measurement at diagnosis in terms of predicting the probability of OS. Conclusion For most patients, the presence of TEL-AML1 fusion gene at diagnosis suggests a favorable prognosis. The present study suggests that persistence of TEL-AML1 fusion as MRD has no additive prognostic value.

  19. Arginine side chain interactions and the role of arginine as a gating charge carrier in voltage sensitive ion channels

    Science.gov (United States)

    Armstrong, Craig T.; Mason, Philip E.; Anderson, J. L. Ross; Dempsey, Christopher E.

    2016-02-01

    Gating charges in voltage-sensing domains (VSD) of voltage-sensitive ion channels and enzymes are carried on arginine side chains rather than lysine. This arginine preference may result from the unique hydration properties of the side chain guanidinium group which facilitates its movement through a hydrophobic plug that seals the center of the VSD, as suggested by molecular dynamics simulations. To test for side chain interactions implicit in this model we inspected interactions of the side chains of arginine and lysine with each of the 19 non-glycine amino acids in proteins in the protein data bank. The arginine guanidinium interacts with non-polar aromatic and aliphatic side chains above and below the guanidinium plane while hydrogen bonding with polar side chains is restricted to in-plane positions. In contrast, non-polar side chains interact largely with the aliphatic part of the lysine side chain. The hydration properties of arginine and lysine are strongly reflected in their respective interactions with non-polar and polar side chains as observed in protein structures and in molecular dynamics simulations, and likely underlie the preference for arginine as a mobile charge carrier in VSD.

  20. L-arginine:glycine amidinotransferase deficiency protects from metabolic syndrome.

    Science.gov (United States)

    Choe, Chi-un; Nabuurs, Christine; Stockebrand, Malte C; Neu, Axel; Nunes, Patricia; Morellini, Fabio; Sauter, Kathrin; Schillemeit, Stefan; Hermans-Borgmeyer, Irm; Marescau, Bart; Heerschap, Arend; Isbrandt, Dirk

    2013-01-01

    Phosphorylated creatine (Cr) serves as an energy buffer for ATP replenishment in organs with highly fluctuating energy demand. The central role of Cr in the brain and muscle is emphasized by severe neurometabolic disorders caused by Cr deficiency. Common symptoms of inborn errors of creatine synthesis or distribution include mental retardation and muscular weakness. Human mutations in l-arginine:glycine amidinotransferase (AGAT), the first enzyme of Cr synthesis, lead to severely reduced Cr and guanidinoacetate (GuA) levels. Here, we report the generation and metabolic characterization of AGAT-deficient mice that are devoid of Cr and its precursor GuA. AGAT-deficient mice exhibited decreased fat deposition, attenuated gluconeogenesis, reduced cholesterol levels and enhanced glucose tolerance. Furthermore, Cr deficiency completely protected from the development of metabolic syndrome caused by diet-induced obesity. Biochemical analyses revealed the chronic Cr-dependent activation of AMP-activated protein kinase (AMPK), which stimulates catabolic pathways in metabolically relevant tissues such as the brain, skeletal muscle, adipose tissue and liver, suggesting a mechanism underlying the metabolic phenotype. In summary, our results show marked metabolic effects of Cr deficiency via the chronic activation of AMPK in a first animal model of AGAT deficiency. In addition to insights into metabolic changes in Cr deficiency syndromes, our genetic model reveals a novel mechanism as a potential treatment option for obesity and type 2 diabetes mellitus.

  1. Solid residues

    International Nuclear Information System (INIS)

    Mulder, E.; Duin, P.J. van; Grootenboer, G.J.

    1995-01-01

    A summary is presented of the many investigations that have been done on solid residues of atmospheric fluid bed combustion (AFBC). These residues are bed ash, cyclone ash and bag filter ash. Physical and chemical properties are discussed and then the various uses of residues (in fillers, bricks, gravel, and for recovery of aluminium) are summarised. Toxicological properties of fly ash and stack ash are discussed as are risks of pneumoconiosis for workers handling fly ash, and contamination of water by ashes. On the basis of present information it is concluded that risks to public health from exposure to emissions of coal fly ash from AFBC appear small or negligible as are health risk to workers in the coal fly ash processing industry. 35 refs., 5 figs., 12 tabs

  2. Chemical modifications in solarized soil with addition of organic residues/ Modificações químicas em solo solarizado, com e sem incorporação de resíduos orgânicos

    Directory of Open Access Journals (Sweden)

    Carlos Roberto Padovani

    2008-08-01

    Full Text Available The soil solarization is used in small properties as an alternative for control of phytopathogens and weeds, besides it also can affect the availability of some nutrients and phytotoxic elements in the soil. Thus, one experiment was carried out as a three-factor factorial (solarized and not solarized soil x with and without addition of vegetable residue x four collection times for evaluation of variations of pH, organic matter, phosphorus, total nitrogen, potassium, calcium, magnesium and aluminum in a soil characterized as Distrofic Red Latosoil, in Botucatu county (SP. The incorporated vegetable residue was constituted of crop remains of kale (Brassica oleraceae var. acephala L. fresh and triturated. Soil samples of each treatment were collected from zero to 0.1m of depth, at 7, 21, 35, and 49 days after solarization treatment, from January to March of 2001. Soil chemical analyses were done as well as the soil temperature were monitored on the treatments. The solarized soil with kale organic residues addition treatment presented higher values of pH, organic matter, total nitrogen, phosphorus, potassium, calcium, magnesium and minor values of aluminum.A solarização de solo é empregada em pequenas propriedades no controle alternativo de fitopatógenos e plantas invasoras, podendo também afetar a disponibilidade de alguns nutrientes e elementos fitotóxicos no solo. Desta forma elaborou-se o ensaio com delineamento fatorial 2x2x4 (solo solarizado e não solarizado x com e sem adição de resíduo vegetal x 4 épocas de coleta para o acompanhamento das variações de pH, matéria orgânica, fósforo, nitrogênio total, potássio, cálcio, magnésio e alumínio em solo caracterizado como Latossolo Vermelho Distrófico, em Botucatu (SP. O resíduo vegetal incorporado foi constituído de restos culturais de couve (Brassica oleraceae var. acephala L. frescos e triturados. Amostras de solo de cada tratamento foram coletadas de zero a 0,1m de

  3. To assess whether indoor residual spraying can provide additional protection against clinical malaria over current best practice of long-lasting insecticidal mosquito nets in The Gambia: study protocol for a two-armed cluster-randomised trial

    Directory of Open Access Journals (Sweden)

    Parker David

    2011-06-01

    Full Text Available Abstract Background Recently, there has been mounting interest in scaling-up vector control against malaria in Africa. It needs to be determined if indoor residual spraying (IRS with DDT will provide significant marginal protection against malaria over current best practice of long-lasting insecticidal nets (LLINs and prompt treatment in a controlled trial, given that DDT is currently the most persistent insecticide for IRS. Methods A 2 armed cluster-randomised controlled trial will be conducted to assess whether DDT IRS and LLINs combined provide better protection against clinical malaria in children than LLINs alone in rural Gambia. Each cluster will be a village, or a group of small adjacent villages; all clusters will receive LLINs and half will receive IRS in addition. Study children, aged 6 months to 13 years, will be enrolled from all clusters and followed for clinical malaria using passive case detection to estimate malaria incidence for 2 malaria transmission seasons in 2010 and 2011. This will be the primary endpoint. Exposure to malaria parasites will be assessed using light and exit traps followed by detection of Anopheles gambiae species and sporozoite infection. Study children will be surveyed at the end of each transmission season to estimate the prevalence of Plasmodium falciparum infection and the prevalence of anaemia. Discussion Practical issues concerning intervention implementation, as well as the potential benefits and risks of the study, are discussed. Trial Registration ISRCTN01738840 - Spraying And Nets Towards malaria Elimination (SANTE

  4. The effect of arginine on oral biofilm communities.

    Science.gov (United States)

    Nascimento, M M; Browngardt, C; Xiaohui, X; Klepac-Ceraj, V; Paster, B J; Burne, R A

    2014-02-01

    Alkali production by oral bacteria via the arginine deiminase system (ADS) increases the pH of oral biofilms and reduces the risk for development of carious lesions. This study tested the hypothesis that increased availability of arginine in the oral environment through an exogenous source enhances the ADS activity levels in saliva and dental plaque. Saliva and supra-gingival plaque samples were collected from 19 caries-free (CF) individuals (DMFT = 0) and 19 caries-active (CA) individuals (DMFT ≥ 2) before and after treatment, which comprised the use of a fluoride-free toothpaste containing 1.5% arginine, or a regular fluoride-containing toothpaste twice daily for 4 weeks. ADS activity was measured by quantification of ammonia produced from arginine by oral samples at baseline, after washout period, 4 weeks of treatment, and 2 weeks post-treatment. Higher ADS activity levels were observed in plaque samples from CF compared to those of CA individuals (P = 0.048) at baseline. The use of the arginine toothpaste significantly increased ADS activity in plaque of CA individuals (P = 0.026). The plaque microbial profiles of CA treated with the arginine toothpaste showed a shift in bacterial composition to a healthier community, more similar to that of CF individuals. Thus, an anti-caries effect may be expected from arginine-containing formulations due in large part to the enhancement of ADS activity levels and potential favorable modification to the composition of the oral microbiome. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  5. L-Arginine Supplementation and Metabolism in Asthma

    Directory of Open Access Journals (Sweden)

    Angela Linderholm

    2011-01-01

    Full Text Available L-Arginine, the amino acid substrate for nitric oxide synthase, has been tested as a therapeutic intervention in a variety of chronic diseases and is commonly used as a nutritional supplement. In this study, we hypothesized that a subset of moderate to severe persistent asthma patients would benefit from supplementation with L-arginine by transiently increasing nitric oxide levels, resulting in bronchodilation and a reduction in inflammation. The pilot study consisted of a 3 month randomized, double-blind, placebo-controlled trial of L-arginine (0.05 g/kg twice daily in patients with moderate to severe asthma. We measured spirometry, exhaled breath nitric oxide, serum arginine metabolites, questionnaire scores, daily medication use and PEFR with the primary endpoint being the number of minor exacerbations at three months. Interim analysis of the 20 subjects showed no difference in the number of exacerbations, exhaled nitric oxide levels or lung function between groups, though participants in the L-arginine group had higher serum L-arginine at day 60 (2.0 ± 0.6 × 10−3 vs. 1.1 ± 0.2 × 10−3 µmol/L, p < 0.05, ornithine at day 30 (2.4 ± 0.9 vs. 1.2 ± 0.3 µmol/L serum, p < 0.05 and ADMA at day 30 (6.0 ± 1.5 × 10−1 vs. 2.6 ± 0.6 × 10−1 µmol/L serum, p < 0.05 on average compared to the placebo group. The study was terminated prematurely. Supplementing asthma subjects with L-arginine increases plasma levels; whether subgroups might benefit from such supplementation requires further study.

  6. Regulation of Skeletal Muscle Plasticity by Protein Arginine Methyltransferases and Their Potential Roles in Neuromuscular Disorders

    Directory of Open Access Journals (Sweden)

    Derek W. Stouth

    2017-11-01

    Full Text Available Protein arginine methyltransferases (PRMTs are a family of enzymes that catalyze the methylation of arginine residues on target proteins, thereby mediating a diverse set of intracellular functions that are indispensable for survival. Indeed, full-body knockouts of specific PRMTs are lethal and PRMT dysregulation has been implicated in the most prevalent chronic disorders, such as cancers and cardiovascular disease (CVD. PRMTs are now emerging as important mediators of skeletal muscle phenotype and plasticity. Since their first description in muscle in 2002, a number of studies employing wide varieties of experimental models support the hypothesis that PRMTs regulate multiple aspects of skeletal muscle biology, including development and regeneration, glucose metabolism, as well as oxidative metabolism. Furthermore, investigations in non-muscle cell types strongly suggest that proteins, such as peroxisome proliferator-activated receptor-γ coactivator-1α, E2F transcription factor 1, receptor interacting protein 140, and the tumor suppressor protein p53, are putative downstream targets of PRMTs that regulate muscle phenotype determination and remodeling. Recent studies demonstrating that PRMT function is dysregulated in Duchenne muscular dystrophy (DMD, spinal muscular atrophy (SMA, and amyotrophic lateral sclerosis (ALS suggests that altering PRMT expression and/or activity may have therapeutic value for neuromuscular disorders (NMDs. This review summarizes our understanding of PRMT biology in skeletal muscle, and identifies uncharted areas that warrant further investigation in this rapidly expanding field of research.

  7. Arginine-phosphate salt bridges between histones and DNA: Intermolecular actuators that control nucleosome architecture

    Science.gov (United States)

    Yusufaly, Tahir I.; Li, Yun; Singh, Gautam; Olson, Wilma K.

    2014-10-01

    Structural bioinformatics and van der Waals density functional theory are combined to investigate the mechanochemical impact of a major class of histone-DNA interactions, namely, the formation of salt bridges between arginine residues in histones and phosphate groups on the DNA backbone. Principal component analysis reveals that the configurational fluctuations of the sugar-phosphate backbone display sequence-specific directionality and variability, and clustering of nucleosome crystal structures identifies two major salt-bridge configurations: a monodentate form in which the arginine end-group guanidinium only forms one hydrogen bond with the phosphate, and a bidentate form in which it forms two. Density functional theory calculations highlight that the combination of sequence, denticity, and salt-bridge positioning enables the histones to apply a tunable mechanochemical stress to the DNA via precise and specific activation of backbone deformations. The results suggest that selection for specific placements of van der Waals contacts, with high-precision control of the spatial distribution of intermolecular forces, may serve as an underlying evolutionary design principle for the structure and function of nucleosomes, a conjecture that is corroborated by previous experimental studies.

  8. Calculation of additional costs in 2010 - for the demolition of the Swedish nuclear power plants and disposal of residues; Beraekning av merkostnader 2010 - foer rivning av de svenska kaernkraftsverken och omhaendertagande av restprodukter

    Energy Technology Data Exchange (ETDEWEB)

    Brewitz, Erica; Schoultz, Christian; Wetzel, Carina

    2010-09-15

    This report describes the SSM's calculation of additional costs for fee proposal for 2012-2014. The calculation is made pursuant to the Financing Act and includes all additional costs until the residue from the Swedish nuclear power plants is disposed of. According to current calculations, this should be done in 2069. Estimates of such a long time means a great deal of uncertainty and SSM uses, like SKB, the successive calculation method to estimate an expected value and tax association uncertainty. As a starting point for analysis, the SSM has made estimates of the future costs broken down into paragraphs in paragraph 2 Financing Act. The estimates were made after discussions within the organization and representatives of relevant external organizations. Assuming a total annual cost per worker of 1.24 million gave these estimates a total cost of over three billion. It should be emphasized that this sum is only a starting point for analysis and applies in particular circumstances. These circumstances critically reviewed the analysis and the reasonableness of assessments made by a analysis group. The analysis took place for 2.5 days in spring 2010. The analysis group consisted of 17 people including nine from the SSM. Lores Borg and Steen Lichtenberg were moderators. Via a brainstorming process, the analysis group presented a number of uncertainties and made a three-part assessment of their impact on the overall results (minimum, most likely and maximum). The result of the analysis: average in the 2010 monetary value was assessed to 4.24 billion Swedish crowns with a standard deviation of 920 million Swedish crowns. These values are undiscounted

  9. Synthesis of specific deuterium labeled tyrosine and phenylalanine derivatives and their use in the total synthesis of [8-arginine]vasopressin derivatives: the separation of diastereomeric [8-arginine]vasopressin derivatives by partition chromatography

    International Nuclear Information System (INIS)

    Yamamoto, D.M.; Upson, D.A.; Linn, D.K.; Hruby, V.J.

    1977-01-01

    Derivatives of tyrosine specifically deuterated at the α carbon ([α- 2 H 1 ]tyrosine) and at both the α and β carbons ([α,β,β- 2 H 3 ]tyrosine) and a derivative of phenylalanine specifically deuterated at the α carbon ([α- 2 H 1 ]phenylalanine) have been synthesized in high yield. These labeled compounds have been resolved enzymatically, and the enantiomers and racemates have been converted to N-tert-butyloxycarbonyl derivatives. The deuterium labels were not exchanged under the conditions of the syntheses. The protected derivatives as well as specifically deuterated derivatives of S-benzylcysteine and of glycine were used to prepare specifically deuterated analogues of [8-arginine] vasopressin using solid phase peptide procedures. The use of improved synthetic procedures resulted in considerable improvements in the yields of [8-arginine]vasopressin compared with previous reports. In addition, new solvent systems for partition chromatography purification of [8-arginine]vasopressin on Sephadex were developed which allowed a facile one-step separation of diastereomers of [8-arginine]vasopressin containing a racemic amino acid at either the 1-hemicystine or the 2-tyrosine positions of the hormone

  10. Lysine and arginine reduce the effects of cerebral ischemic insults and inhibit glutamate-induced neuronal activity in rats

    Directory of Open Access Journals (Sweden)

    Takashi Kondoh

    2010-06-01

    Full Text Available Intravenous administration of arginine was shown to be protective against cerebral ischemic insults via nitric oxide production and possibly via additional mechanisms. The present study aimed at evaluating the neuroprotective effects of oral administration of lysine (a basic amino acid, arginine, and their combination on ischemic insults (cerebral edema and infarction and hemispheric brain swelling induced by transient middle cerebral artery occlusion/reperfusion in rats. Magnetic resonance imaging and 2,3,5-triphenyltetrazolium chloride staining were performed two days after ischemia induction. In control animals, the major edematous areas were observed in the cerebral cortex and striatum. The volumes associated with cortical edema were significantly reduced by lysine (2.0 g/kg, arginine (0.6 g/kg, or their combined administration (0.6 g/kg each. Protective effects of these amino acids on infarction were comparable to the inhibitory effects on edema formation. Interestingly, these amino acids, even at low dose (0.6 g/kg, were effective to reduce hemispheric brain swelling. Additionally, the effects of in vivo microiontophoretic (juxtaneuronal applications of these amino acids on glutamate-evoked neuronal activity in the ventromedial hypothalamus were investigated in awake rats. Glutamate-induced neuronal activity was robustly inhibited by microiontophoretic applications of lysine or arginine onto neuronal membranes. Taken together, our results demonstrate the neuroprotective effects of oral ingestion of lysine and arginine against ischemic insults (cerebral edema and infarction, especially in the cerebral cortex, and suggest that suppression of glutamate-induced neuronal activity might be the primary mechanism associated with these neuroprotective effects.

  11. Residual basins

    International Nuclear Information System (INIS)

    D'Elboux, C.V.; Paiva, I.B.

    1980-01-01

    Exploration for uranium carried out over a major portion of the Rio Grande do Sul Shield has revealed a number of small residual basins developed along glacially eroded channels of pre-Permian age. Mineralization of uranium occurs in two distinct sedimentary units. The lower unit consists of rhythmites overlain by a sequence of black shales, siltstones and coal seams, while the upper one is dominated by sandstones of probable fluvial origin. (Author) [pt

  12. Gliclazide directly inhibits arginine-induced glucagon release

    DEFF Research Database (Denmark)

    Cejvan, Kenan; Coy, David H; Holst, Jens Juul

    2002-01-01

    Arginine-stimulated insulin and somatostatin release is enhanced by the sulfonylurea gliclazide. In contrast, gliclazide inhibits the glucagon response. The aim of the present study was to investigate whether this inhibition of glucagon release was mediated by a direct suppressive effect of glicl......Arginine-stimulated insulin and somatostatin release is enhanced by the sulfonylurea gliclazide. In contrast, gliclazide inhibits the glucagon response. The aim of the present study was to investigate whether this inhibition of glucagon release was mediated by a direct suppressive effect....... In islet perifusions with DC-41-33, arginine-induced glucagon release was inhibited by 66%. We therefore concluded that gliclazide inhibits glucagon release by a direct action on the pancreatic A cell....

  13. Mitochondria: role of citrulline and arginine supplementation in MELAS syndrome.

    Science.gov (United States)

    El-Hattab, Ayman W; Emrick, Lisa T; Chanprasert, Sirisak; Craigen, William J; Scaglia, Fernando

    2014-03-01

    Mitochondria are found in all nucleated human cells and generate most of the cellular energy. Mitochondrial disorders result from dysfunctional mitochondria that are unable to generate sufficient ATP to meet the energy needs of various organs. Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome is a frequent maternally inherited mitochondrial disorder. There is growing evidence that nitric oxide (NO) deficiency occurs in MELAS syndrome and results in impaired blood perfusion that contributes significantly to several complications including stroke-like episodes, myopathy, and lactic acidosis. Both arginine and citrulline act as NO precursors and their administration results in increased NO production and hence can potentially have therapeutic utility in MELAS syndrome. Citrulline raises NO production to a greater extent than arginine, therefore, citrulline may have a better therapeutic effect. Controlled studies assessing the effects of arginine or citrulline supplementation on different clinical aspects of MELAS syndrome are needed. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Current Understanding of Physicochemical Mechanisms for Cell Membrane Penetration of Arginine-rich Cell Penetrating Peptides: Role of Glycosaminoglycan Interactions.

    Science.gov (United States)

    Takechi-Haraya, Yuki; Saito, Hiroyuki

    2018-01-01

    Arginine-rich cell penetrating peptides (CPPs) are very promising drug carriers to deliver membrane-impermeable pharmaceuticals, such as siRNA, bioactive peptides and proteins. CPPs directly penetrate into cells across cell membranes via a spontaneous energy-independent process, in which CPPs appear to interact with acidic lipids in the outer leaflet of the cell membrane. However, acidic lipids represent only 10 to 20% of the total membrane lipid content and in mammalian cell membranes they are predominantly located in the inner leaflet. Alternatively, CPPs favorably bind in a charge density- dependent manner to negatively charged, sulfated glycosaminoglycans (GAGs), such as heparan sulfate and chondroitin sulfate, which are abundant on the cell surface and are involved in many biological functions. We have recently demonstrated that the interaction of CPPs with sulfated GAGs plays a critical role in their direct cell membrane penetration: the favorable enthalpy contribution drives the high-affinity binding of arginine-rich CPPs to sulfated GAGs, initiating an efficient cell membrane penetration. The favorable enthalpy gain is presumably mainly derived from a unique property of the guanidino group of arginine residues forming multidentate hydrogen bonding with sulfate and carboxylate groups in GAGs. Such interactions can be accompanied with charge neutralization of arginine-rich CPPs, promoting their partition into cell membranes. This review summarizes the current understanding of the physicochemical mechanism for lipid membrane penetration of CPPs, and discusses the role of the GAG interactions on the cell membrane penetration of CPPs. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  15. Plasma glucagon responses to L-arginine in various diseases

    International Nuclear Information System (INIS)

    Morita, Nobuto; Hayakawa, Hiroyuki; Kawai, Kohzo; Noto, Yutaka; Ohno, Taro

    1978-01-01

    To clarify the mechanism of abnormal glucose metabolism in the secondary diabetes, we examined the dynamics of plasma glucagon levels in various diseases which may accompany glucose intolerance. Plasma glucagon responses to L-arginine were observed in 20 liver cirrhotics, 8 patients with chronic renal failure, 6 patients with chronic pancreatitis, 4 patients, with hyperthyroidism, 22 diabetics and 9 normal controls. Plasma glucagon levels were determined by the radioimmunoassay method of Unger using 125 I-glucagon and antiserum 30K which is specific for pancreatic glucagon. In the cirrhotics, the plasma glucagon responses to L-arginine were significantly higher than in normal controls. The patients whose BSP retention at 45 minutes were above 30% showed higher plasma glucagon responses than in the patients whose BSP retention at 45 minutes were below 30%, suggesting that the more severely the liver was damaged, the more the plasma glucagon levels were elevated. In the patients with chronic renal failure, the plasma glucagon responses to L-arginine were also significantly higher than in normal controls. These abnormal levels were not improved by a hemodialysis, although serum creatinine levels were fairly decreased. In the patients with chronic pancreatitis, the plasma glucagon responses to L-arginine were the same as those in normal controls. In the patients with hyperthyroidism the plasma glucagon responses to L-arginine seemed to be lower than normal controls. In the diabetics, the plasma glucagon responses to L-arginine were almost the same as in normal controls. However their glucagon levels seemed to be relatively high, considering the fact that diabetics had high blood glucose levels. (auth.)

  16. Selective effects of charge on G protein activation by FSH-receptor residues 551-555 and 650-653.

    Science.gov (United States)

    Grasso, P; Deziel, M R; Reichert, L E

    1995-01-01

    Two cytosolic regions of the rat testicular FSH receptor (FSHR), residues 533-555 and 645-653, have been identified as G protein-coupling domains. We localized the activity in these domains to their C-terminal sequences, residues 551-555 (KIAKR, net charge +3) and 650-653 (RKSH, net charge +3), and examined the effects of charge on G protein activation by the C-terminal peptides, using synthetic analogs containing additions, through alanine (A) linkages, of arginine (R, +), histidine (H, +) or both. RA-KIAKR (net charge +4) mimicked the effect of FSHR-(551-555) on guanine nucleotide exchange in rat testis membranes, but reduced its ability to inhibit FSH-stimulated estradiol biosynthesis in cultured rat Sertoli cells. Further increasing net charge by the addition of H (HARA-KIAKR, net charge +5) increased guanosine 5'-triphosphate (GTP) binding, but eliminated FSHR-(551-555) effects on FSH-stimulated steroidogenesis. HA-RKSH (net charge +4) significantly inhibited guanine nucleotide exchange in rat testis membranes, but stimulated basal and potentiated FSH-induced estradiol biosynthesis in cultured rat Sertoli cells. Addition of two H residues (HAHA-RKSH, net charge +5) restored GTP binding and further potentiated basal and FSH-stimulated steroidogenesis. These results suggest that positive charges in G protein-coupling domains of the FSHR play a role in modulating G protein activation and postbinding effects of FSH, such as steroidogenesis.

  17. Phase equilibria in a system of aqueous arginine with an octane solution of sulfonic acid

    Science.gov (United States)

    Kuvaeva, Z. I.; Koval'chuk, I. V.; Vodop'yanova, L. A.; Soldatov, V. S.

    2013-05-01

    The extraction of arginine (Arg) from aqueous salt (0.1 M NaCl) solutions with a sulfo extractant in a wide range of pH values and amino acid concentrations was studied. The 0.1 M solution of dinonylnaphthalenesulfonic acid (HD) in octane was used as an extractant. The degree of extraction was found to be high at pH 0.8-9.0. This can be explained by the effect of additional intermolecular interactions in the extractant phase involving the guanidine group of Arg.

  18. Arginine intake and risk of coronary heart disease mortality in elderly men

    NARCIS (Netherlands)

    Oomen, C.M.; Erk, van M.J.; Feskens, E.J.M.; Kok, F.J.; Kromhout, D.

    2000-01-01

    From experimental studies, the hypothesis is derived that the amino acid arginine, the precursor of NO, could restore the impaired endothelial function and increased platelet activation observed in atherosclerosis. We investigated whether dietary intake of arginine is associated with reduced

  19. Effects of dietary L-arginine on orthodontic tooth movement in rats

    African Journals Online (AJOL)

    Yomi

    2012-01-03

    Jan 3, 2012 ... arginine in drinking water six days before the insertion of springs to ... Key words: L-Arginine, dietary, orthodontic tooth movement, nitric oxide, root resorption, osteoclast, .... cAMP, interleukin 1-beta and neurotransmitters are.

  20. The Arginine/ADMA Ratio Is Related to the Prevention of Atherosclerotic Plaques in Hypercholesterolemic Rabbits When Giving a Combined Therapy with Atorvastatine and Arginine

    Directory of Open Access Journals (Sweden)

    Saskia J. H. Brinkmann

    2015-05-01

    Full Text Available Supplementation with arginine in combination with atorvastatin is more efficient in reducing the size of an atherosclerotic plaque than treatment with a statin or arginine alone in homozygous Watanabe heritable hyperlipidemic (WHHL rabbits. We evaluated the mechanism behind this feature by exploring the role of the arginine/asymmetric dimethylarginine (ADMA ratio, which is the substrate and inhibitor of nitric oxide synthase (NOS and thereby nitric oxide (NO, respectively. Methods: Rabbits were fed either an arginine diet (group A, n = 9, standard rabbit chow plus atorvastatin (group S, n = 8, standard rabbit chow plus an arginine diet with atorvastatin (group SA, n = 8 or standard rabbit chow (group C, n = 9 as control. Blood was sampled and the aorta was harvested for topographic and histological analysis. Plasma levels of arginine, ADMA, cholesterol and nitric oxide were determined and the arginine/ADMA ratio was calculated. Results: The decrease in ADMA levels over time was significantly correlated to fewer aortic lesions in the distal aorta and total aorta. The arginine/ADMA ratio was correlated to cholesterol levels and decrease in cholesterol levels over time in the SA group. A lower arginine/ADMA ratio was significantly correlated to lower NO levels in the S and C group. Discussion: A balance between arginine and ADMA is an important indicator in the prevention of the development of atherosclerotic plaques.

  1. The role of arginine and the modified arginine deiminase enzyme ADI-PEG 20 in cancer therapy with special emphasis on Phase I/II clinical trials.

    Science.gov (United States)

    Synakiewicz, Anna; Stachowicz-Stencel, Teresa; Adamkiewicz-Drozynska, Elzbieta

    2014-11-01

    The metabolic differences between normal, healthy cells and neoplastic cells have been exploited by anticancer therapies targeting metabolic pathways. Various studies of malignant processes have demonstrated disturbances in both arginine synthesis and metabolism that enhance or inhibit tumor cell growth. Consequently, there has been an increased interest in the arginine-depleting enzyme arginine deiminase (ADI) as a potential antineoplastic therapy. This review summarizes the literature on the potential anti-cancer therapeutics arginine and ADI, an arginine-catabolizing enzyme. The authors searched the MEDLINE database PubMed using the key words: 'arginine, 'ADI', 'arginine in cancer' and 'ADI and cancer'. The authors evaluate prospective randomized studies on cancer patients between 2004 and 2013 as well as ongoing research found through the US National Institutes of Health trial database. The results of current studies are promising but do not give unequivocal answers and so it is impossible to recommend arginine or its enzyme ADI as a therapeutic. In the opinion of the authors, further identification of arginine-dependent malignant tumors and their metabolism should be investigated. Furthermore, the use of these chemicals, in combination with other chemotherapeutics drugs, should be investigated and indeed may improve the success of arginine-depleting enzymes such as pegylated ADI (ADI-PEG20).

  2. A forma de aplicação da uréia e dos resíduos vegetais afeta a disponibilidade de nitrogênio The addition form of crop residues and urea interfers on nitrogen availability

    Directory of Open Access Journals (Sweden)

    Paulo Roberto Ernani

    2005-04-01

    Full Text Available O método de aplicação dos resíduos vegetais e dos fertilizantes nitrogenados pode afetar as reações do nitrogênio no solo, principalmente no plantio direto. O presente trabalho objetivou avaliar esses efeitos na disponibilidade de N para o milho em dois solos, em casa-de-vegetação. Combinações de métodos (ausência, incorporada ou na superfície de adição de palha de aveia (0,4kg m-2 e uréia (50mg N kg-1 foram aplicadas em unidades experimentais (7dm³ vaso-1 de dois solos, perfazendo um fatorial 3 x 3 x 2. O milho foi semeado no dia da aplicação dos tratamentos e as plantas foram cultivadas durante trinta dias, sobre um Neossolo e um Nitossolo, respectivamente com 50 e 520g kg-1 de argila e 8 e 48g kg-1 de matéria orgânica. A aplicação de palha de aveia, principalmente sobre a superfície do solo, beneficiou o desenvolvimento das plantas, possivelmente pela manutenção de maior quantidade de umidade nos solos. A aplicação de uréia não afetou nenhum parâmetro vegetal no solo argiloso, talvez porque a decomposição da matéria orgânica liberou mais N do que a imobilização ocasionada durante a decomposição da palha; no solo arenoso, entretanto, a uréia foi benéfica quando incorporada ao solo, e prejudicial quando adicionada na superfície, provavelmente devido à toxidez de amônia. Dessa forma, o efeito da decomposição da palha de aveia na disponibilidade de N foi função do teor de matéria orgânica original do solo.Management of both crop residues and nitrogen fertilizers affects soil N reactions especially on no-till systems. The magnitude of these effects on N availability to maize was evaluated in a greenhouse study. Combinations of oat straw and urea (absence, soil incorporated or surface applied were added to experimental units (7-dm³ per pot of two soils, in a 3 x 3 x 2 factorial combination. Plants were sown just following treatments addition, and grown for thirty days in two soils (Typic

  3. Effects of Arginine Vasopressin on musical short-term memory

    Directory of Open Access Journals (Sweden)

    Roni Y. Granot

    2013-10-01

    Full Text Available Previous genetic studies showed an association between variations in the gene coding for the 1a receptor of the neuro-hormone arginine vasopressin (AVP and musical working memory (WM. The current study set out to test the influence of intranasal administration (INA of AVP on musical as compared to verbal WM using a double blind crossover (AVP – placebo design. Two groups of 25 males were exposed to 20 IU of AVP in one session, and 20 IU of saline water (placebo in a second session, one week apart. In each session subjects completed the tonal subtest from Gordon's Musical Aptitude Profile, the interval subtest from the Montreal Battery for Evaluation of Amusias (MBEA, and the forward and backward digit span tests. Scores in the digit span tests were not influenced by AVP. In contrast, in the music tests there was an AVP effect. In the MBEA test, scores for the group receiving placebo in the first session (PV were higher than for the group receiving vasopressin in the first session (VP (p < .05 with no main Session effect nor Group * Session interaction. In the Gordon test there was a main Session effect (p < .05 with scores higher in the second as compared to the first session, a marginal main Group effect (p = .093 and a marginal Group X Session interaction (p = 0.88. In addition we found that the group that received AVP in the first session scored higher on scales indicative of happiness, and alertness on the Positive and Negative Affect Scale, (PANAS. Only in this group and only in the music test these scores were significantly correlated with memory scores. Together the results reflect a complex interaction between AVP, musical memory, arousal, and contextual effects such as session, and base levels of memory. The results are interpreted in light of music's universal use as a means to modulate arousal on the one hand, and AVP's influence on mood, arousal, and social interactions on the other.

  4. Crystal structure of arginine methyltransferase 6 from Trypanosoma brucei.

    Directory of Open Access Journals (Sweden)

    Chongyuan Wang

    Full Text Available Arginine methylation plays vital roles in the cellular functions of the protozoan Trypanosoma brucei. The T. brucei arginine methyltransferase 6 (TbPRMT6 is a type I arginine methyltransferase homologous to human PRMT6. In this study, we report the crystal structures of apo-TbPRMT6 and its complex with the reaction product S-adenosyl-homocysteine (SAH. The structure of apo-TbPRMT6 displays several features that are different from those of type I PRMTs that were structurally characterized previously, including four stretches of insertion, the absence of strand β15, and a distinct dimerization arm. The comparison of the apo-TbPRMT6 and SAH-TbPRMT6 structures revealed the fine rearrangements in the active site upon SAH binding. The isothermal titration calorimetry results demonstrated that SAH binding greatly increases the affinity of TbPRMT6 to a substrate peptide derived from bovine histone H4. The western blotting and mass spectrometry results revealed that TbPRMT6 methylates bovine histone H4 tail at arginine 3 but cannot methylate several T. brucei histone tails. In summary, our results highlight the structural differences between TbPRMT6 and other type I PRMTs and reveal that the active site rearrangement upon SAH binding is important for the substrate binding of TbPRMT6.

  5. Arginine-dependent acid resistance in Salmonella enterica serovar Typhimurium

    NARCIS (Netherlands)

    Kieboom, J.; Abee, T.

    2006-01-01

    Salmonella enterica serovar Typhimurium does not survive a pH 2.5 acid challenge under conditions similar to those used for Escherichia coli (J. W. Foster, Nat. Rev. Microbiol. 2:898-907, 2004). Here, we provide evidence that S. enterica serovar Typhimurium can display arginine-dependent acid

  6. Glutamine-enriched enteral diet increases renal arginine production

    NARCIS (Netherlands)

    Houdijk, A. P.; van Leeuwen, P. A.; Teerlink, T.; FLINKERBUSCH, E. L.; Boermeester, M. A.; Sauerwein, H. P.; Wesdorp, R. I.

    1994-01-01

    Arginine (Arg) is generated in the kidney by the conversion of circulating citrulline. The most important source for circulating citrulline is the metabolism of glutamine (Gln) by the gut. In this study, we investigated the influence of an enteral diet enriched with Gln on renal Arg synthesis in the

  7. Effect of iron, taurine and arginine on rat hepatic fibrosis

    International Nuclear Information System (INIS)

    Song Liangwen; Wang Dewen; Cui Xuemei

    1997-01-01

    Objective: The promotion role of iron on pathogenesis of hepatic fibrosis and the protective role of taurine and L-arginine against hepatic fibrosis were studied. Method: The model of rat radiation hepatic fibrosis was used. Experimental rats were divided into 0 Gy, 30 Gy, 30 Gy + iron, 30 Gy + taurine and 30 Gy + L-arginine groups. Serum iron, liver tissue hydroxyproline (Hyp) and malondialdehyde (MDA) were measured one and three months respectively after irradiation of hepatic tissue, production and distribution characteristics of hepatic tissue type I and III collagen were observed with a polarizing microscope. Results: Administration of iron agent could significantly increase hepatic tissue MDA content and serum iron concentration, one month after irradiation, hepatic tissue Hyp in 30 Gy + iron group began to increase, and collagen in hepatic tissue obviously increased. Taurine and L-arginine could reduce serum iron concentration and decrease production of hepatic fissure Hyp. Conclusion: Exogenous iron agent could promote early development of radiation hepatic fibrosis; taurine and arginine could diminish pathologic alteration of hepatic fibrosis to a certain extent

  8. Lysine, Arginine, and Histidine Residues in Peptide-Catalyzed Hydrogen Evolution at Mercury Electrodes

    Czech Academy of Sciences Publication Activity Database

    Dorčák, Vlastimil; Vargová, Veronika; Ostatná, Veronika; Paleček, Emil

    2015-01-01

    Roč. 27, č. 4 (2015), s. 910-916 ISSN 1040-0397 R&D Projects: GA ČR(CZ) GA15-15479S; GA ČR(CZ) GA13-00956S Institutional support: RVO:68081707 Keywords : AMALGAM ELECTRODES * STRIPPING CHRONOPOTENTIOMETRY * CARBON ELECTRODES Subject RIV: BO - Biophysics Impact factor: 2.471, year: 2015

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

    Science.gov (United States)

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

    2014-08-01

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

  10. Effect of methylation on the side-chain pKa value of arginine.

    Science.gov (United States)

    Evich, Marina; Stroeva, Ekaterina; Zheng, Yujun George; Germann, Markus W

    2016-02-01

    Arginine methylation is important in biological systems. Recent studies link the deregulation of protein arginine methyltransferases with certain cancers. To assess the impact of methylation on interaction with other biomolecules, the pKa values of methylated arginine variants were determined using NMR data. The pKa values of monomethylated, symmetrically dimethylated, and asymmetrically dimethylated arginine are similar to the unmodified arginine (14.2 ± 0.4). Although the pKa value has not been significantly affected by methylation, consequences of methylation include changes in charge distribution and steric effects, suggesting alternative mechanisms for recognition. © 2015 The Protein Society.

  11. Residual nilpotence and residual solubility of groups

    International Nuclear Information System (INIS)

    Mikhailov, R V

    2005-01-01

    The properties of the residual nilpotence and the residual solubility of groups are studied. The main objects under investigation are the class of residually nilpotent groups such that each central extension of these groups is also residually nilpotent and the class of residually soluble groups such that each Abelian extension of these groups is residually soluble. Various examples of groups not belonging to these classes are constructed by homological methods and methods of the theory of modules over group rings. Several applications of the theory under consideration are presented and problems concerning the residual nilpotence of one-relator groups are considered.

  12. In vivo whole body and organ arginine metabolism during endotoxemia (sepsis) is dependent on mouse strain and gender

    NARCIS (Netherlands)

    Luiking, Y. C.; Hallemeesch, M. M.; Vissers, Y. L. J.; Lamers, W. H.; Deutz, N. E. P.

    2004-01-01

    Arginine metabolism involves various organs such as the kidney, the intestines, and the liver, which act together in an interorgan axis. Major pathways for arginine production are protein breakdown and de novo arginine production from citrulline; disposal of arginine is mainly used for protein

  13. Restoration of impaired nitric oxide production in MELAS syndrome with citrulline and arginine supplementation.

    Science.gov (United States)

    El-Hattab, Ayman W; Hsu, Jean W; Emrick, Lisa T; Wong, Lee-Jun C; Craigen, William J; Jahoor, Farook; Scaglia, Fernando

    2012-04-01

    Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome is one of the most common mitochondrial disorders. Although the pathogenesis of stroke-like episodes remains unclear, it has been suggested that mitochondrial proliferation may result in endothelial dysfunction and decreased nitric oxide (NO) availability leading to cerebral ischemic events. This study aimed to assess NO production in subjects with MELAS syndrome and the effect of the NO precursors arginine and citrulline. Using stable isotope infusion techniques, we assessed arginine, citrulline, and NO metabolism in control subjects and subjects with MELAS syndrome before and after arginine or citrulline supplementation. The results showed that subjects with MELAS had lower NO synthesis rate associated with reduced citrulline flux, de novo arginine synthesis rate, and plasma arginine and citrulline concentrations, and higher plasma asymmetric dimethylarginine (ADMA) concentration and arginine clearance. We conclude that the observed impaired NO production is due to multiple factors including elevated ADMA, higher arginine clearance, and, most importantly, decreased de novo arginine synthesis secondary to decreased citrulline availability. Arginine and, to a greater extent, citrulline supplementation increased the de novo arginine synthesis rate, the plasma concentrations and flux of arginine and citrulline, and NO production. De novo arginine synthesis increased markedly with citrulline supplementation, explaining the superior efficacy of citrulline in increasing NO production. The improvement in NO production with arginine or citrulline supplementation supports their use in MELAS and suggests that citrulline may have a better therapeutic effect than arginine. These findings can have a broader relevance for other disorders marked by perturbations in NO metabolism. Copyright © 2012 Elsevier Inc. All rights reserved.

  14. Development and cytotoxicity of Schiff base derivative as a fluorescence probe for the detection of L-Arginine

    Science.gov (United States)

    Shang, Xuefang; Li, Jie; Guo, Kerong; Ti, Tongyu; Wang, Tianyun; Zhang, Jinlian

    2017-04-01

    Inspired from biological counter parts, chemical modification of Schiff base derivatives with function groups may provide a highly efficient method to detect amino acids. Therefore, a fluorescent probe involving Schiff base and hydroxyl group has been designed and prepared, which showed high response and specificity for Arginine (Arg) among normal eighteen standard kinds of amino acids (Alanine, Valine, Leucine, Isoleucine, Methionine, Asparticacid, Glutamicacid, Arginine, Glycine, Serine, Threonine, Asparagine, Phenylalanine, Histidine, Tryptophan, Proline, Lysine, Glutamine, Tyrosine and Cysteine). Furthermore, theoretical investigation further illustrated the possible binding mode in the host-guest interaction and the roles of molecular frontier orbitals in molecular interplay. In addition, the synthesized fluorescent probe exhibited high binding ability for Arg and low cytotoxicity to MCF-7 cells over a concentration range of 0-200 μg mL-1 which can be also used as a biosensor for the Arg detection in vivo.

  15. Arginine inhibits the malignant transformation induced by interferon-gamma through the NF-κB-GCN2/eIF2α signaling pathway in mammary epithelial cells in vitro and in vivo.

    Science.gov (United States)

    Ren, Wenbo; Li, Yang; Xia, Xiaojing; Guo, Wenfei; Zhai, Taiyu; Jin, Yuting; Che, Yanyi; Gao, Haidi; Duan, Xiumei; Ma, Hongxi; Huang, Tinghao; Huang, Jing; Lei, Liancheng

    2018-07-15

    Breast cancer is the most common female malignant tumors in the world. It seriously affects women's physical and mental health and the leading cause of cancer death among women. Our previous study demonstrated that diet-derived IFN-γ promoted the malignant transformation of primary bovine mammary epithelial cells by accelerating arginine depletion. The current study aimed to explore whether arginine addition could inhibit the degree of malignant transformation and its molecular mechanism. The results indicate that arginine addition could alleviate the malignant transformation of mammary epithelial cells induced by IFN-γ, including reducing cell proliferation, cell migration and colony formation, through the NF-κB-GCN2/eIF2α pathway. The in vivo experiments also consistently confirmed that arginine supplementation could significantly inhibit tumor growth in tumor-bearing mice. Furthermore, the investigation of the clinical data also revealed that the plasma or tissue from human breast cancer patients owned lower arginine level and higher IFN-γ level than that from patients with benign breast disease, showing IFN-γ may be a potential control target. Our findings demonstrate that arginine supplement could antagonize the malignant transformation of mammary epithelial cells induced by IFN-γ (nutritionally induced) both in vitro and in vivo, and IFN-γ was higher in breast cancer women. This might provide a novel strategy for the prevention and treatment of breast cancer regarding to nutrition. Copyright © 2018 Elsevier Inc. All rights reserved.

  16. Theoretical study about L-arginine complexes formation with thiotriazolin

    Directory of Open Access Journals (Sweden)

    L. I. Kucherenko

    2017-02-01

    Full Text Available Brain vascular diseases are one of the leading causes of morbidity, mortality and disability of population in the industrialized countries of the world. An important element of this problem’s solution is the creation of new highly effective and safe drugs, which would lead to mortality reduction, to increase in life expectancy and quality of life. Therefore it is interesting to create a new combined drug based on L-arginine and thiotriazolin. Purpose of the study: to consider the possible structure and energy characteristics of complexes formed by L-arginine, 3-methyl-1,2,4-triazolyl-5-thioacetate (MTTA and morpholine. Calculation method. The initial approximation to the complex geometry was obtained using molecular docking with the help of AutoDock Vina program. The obtained ternary complexes were pre-optimized by semi-empirical PM7 method with modeling the impact of the environment by COSMO method. The calculations were carried out using MOPAC2012 program. Then they were optimized by B97-D3/SVP + COSMO (Water dispersion-corrected DFT-D with geometrical spreading correction on insufficiency of gCP basis set. A more accurate calculation of the solvation energy was conducted by SMD. The calculations by density functional method were carried out using the ORCA 3.0.3 software. Energy complex formation in solution was calculated as the difference of the Gibbs free energy of the solvated complex and its individual components. Results. Quantum chemical calculations show, that thiotriazolin and L-arginine are able to form ternary complexes, where molecules are linked by multiple hydrogen bonds. The calculation data suggest, that studied complexes are thermodynamically unstable in solution. The energies of them are positive, but rather low despite charge gain of a number of intermolecular hydrogen bonds. Finding. Based on the results of the conducted quantum-chemical study of a three components system (MTTA, morpholine, and L-arginine it is possible

  17. Protein arginine methyltransferase 5 regulates multiple signaling pathways to promote lung cancer cell proliferation

    International Nuclear Information System (INIS)

    Sheng, Xiumei; Wang, Zhengxin

    2016-01-01

    Protein arginine methyltransferase 5 (PRMT5) catalyzes the formation of symmetrical dimethylation of arginine residues in proteins. WD repeat domain 77 (WDR77), also known as p44, MEP50, or WD45, forms a stoichiometric complex with PRMT5. The PRMT5/p44 complex is required for cellular proliferation of lung and prostate epithelial cells during earlier stages of development and is re-activated during prostate and lung tumorigenesis. The molecular mechanisms by which PRMT5 and p44 promote cellular proliferation are unknown. Expression of PRMT5 and p44 in lung and prostate cancer cells was silenced and their target genes were identified. The regulation of target genes was validated in various cancer cells during lung development and tumorigenesis. Altered expression of target genes was achieved by ectopic cDNA expression and shRNA-mediated silencing. PRMT5 and p44 regulate expression of a specific set of genes encoding growth and anti-growth factors, including receptor tyrosine kinases and antiproliferative proteins. Genes whose expression was suppressed by PRMT5 and p44 encoded anti-growth factors and inhibited cell growth when ectopically expressed. In contrast, genes whose expression was enhanced by PRMT5 and p44 encoded growth factors and increased cell growth when expressed. Altered expression of target genes is associated with re-activation of PRMT5 and p44 during lung tumorigenesis. Our data provide the molecular basis by which PRMT5 and p44 regulate cell growth and lay a foundation for further investigation of their role in lung tumor initiation. The online version of this article (doi:10.1186/s12885-016-2632-3) contains supplementary material, which is available to authorized users

  18. Evolution of the Maillard Reaction in Glutamine or Arginine-Dextrinomaltose Model Systems

    Directory of Open Access Journals (Sweden)

    Silvia Pastoriza

    2016-12-01

    Full Text Available Enteral formulas are foods designed for medical uses to feed patients who are unable to eat normally. They are prepared by mixing proteins, amino acids, carbohydrates and fats and submitted to sterilization. During thermal treatment, the Maillard reaction takes place through the reaction of animo acids with reducing sugars. Thus, although glutamine and arginine are usually added to improve the nutritional value of enteral formulas, their final concentration may vary. Thus, in the present paper the early, intermediate, and advanced states of the Maillard reaction were studied in model systems by measuring loss of free amino acids through the decrease of fluorescence intensity with o-phtaldialdehyde (OPA, 5-Hydroximethylfurfural (HMF, furfural, glucosylisomaltol, fluorescence, and absorbance at 420 nm. The systems were prepared by mixing glutamine or arginine with dextrinomaltose (similar ingredients to those used in special enteral formula, and heated at 100 °C, 120 °C and 140 °C for 0 to 30 min. The recorded changes in the concentration of furanic compounds was only useful for longer heating times of high temperatures, while absorbance and fluorescence measurements were useful in all the assayed conditions. In addition, easiness and sensitivity of absorbance and fluorescence make them useful techniques that could be implemented as indicators for monitoring the manufacture of special enteral formulas. Glucosylisomaltol is a useful indicator to monitor the manufacture of glutamine-enriched enteral formulas.

  19. Antiviral and Virucidal Activities of N-Cocoyl-L-Arginine Ethyl Ester

    Directory of Open Access Journals (Sweden)

    Hisashi Yamasaki

    2011-01-01

    Full Text Available Various amino acid-derived compounds, for example, Nα-Cocoyl-L-arginine ethyl ester (CAE, alkyloxyhydroxylpropylarginine, arginine cocoate, and cocoyl glycine potassium salt (Amilite, were examined for their virucidal activities against herpes simplex virus type 1 and 2 (HSV-1 and HSV-2, influenza A virus (IAV, and poliovirus type 1 (PV-1 in comparison to benzalkonium chloride (BKC and sodium dodecylsulfate (SDS as a cationic and anionic control detergent and also to other commercially available disinfectants. While these amino acid-derived compounds were all effective against HSV-1 and HSV-2, CAE and Amilite were the most effective. These two compounds were, however, not as effective against IAV, another enveloped virus, as against HSV. Cytotoxicity of CAE was weak; at 0.012%, only 5% of the cells were killed under the conditions, in which 100% cells were killed by either SDS or BKC. In addition to these direct virucidal effects, CAE inhibited the virus growth in the HSV-1- or PV-1-infected cells even at 0.01%. These results suggest a potential application of CAE as a therapeutic or preventive medicine against HSV superficial infection at body surface.

  20. Evolution of the Maillard Reaction in Glutamine or Arginine-Dextrinomaltose Model Systems.

    Science.gov (United States)

    Pastoriza, Silvia; Rufián-Henares, José Ángel; García-Villanova, Belén; Guerra-Hernández, Eduardo

    2016-12-07

    Enteral formulas are foods designed for medical uses to feed patients who are unable to eat normally. They are prepared by mixing proteins, amino acids, carbohydrates and fats and submitted to sterilization. During thermal treatment, the Maillard reaction takes place through the reaction of animo acids with reducing sugars. Thus, although glutamine and arginine are usually added to improve the nutritional value of enteral formulas, their final concentration may vary. Thus, in the present paper the early, intermediate, and advanced states of the Maillard reaction were studied in model systems by measuring loss of free amino acids through the decrease of fluorescence intensity with o -phtaldialdehyde (OPA), 5-Hydroximethylfurfural (HMF), furfural, glucosylisomaltol, fluorescence, and absorbance at 420 nm. The systems were prepared by mixing glutamine or arginine with dextrinomaltose (similar ingredients to those used in special enteral formula), and heated at 100 °C, 120 °C and 140 °C for 0 to 30 min. The recorded changes in the concentration of furanic compounds was only useful for longer heating times of high temperatures, while absorbance and fluorescence measurements were useful in all the assayed conditions. In addition, easiness and sensitivity of absorbance and fluorescence make them useful techniques that could be implemented as indicators for monitoring the manufacture of special enteral formulas. Glucosylisomaltol is a useful indicator to monitor the manufacture of glutamine-enriched enteral formulas.

  1. Combinatorial Effects of Arginine and Fluoride on Oral Bacteria

    OpenAIRE

    Zheng, X.; Cheng, X.; Wang, L.; Qiu, W.; Wang, S.; Zhou, Y.; Li, M.; Li, Y.; Cheng, L.; Li, J.; Zhou, X.; Xu, X.

    2015-01-01

    Dental caries is closely associated with the microbial disequilibrium between acidogenic/aciduric pathogens and alkali-generating commensal residents within the dental plaque. Fluoride is a widely used anticaries agent, which promotes tooth hard-tissue remineralization and suppresses bacterial activities. Recent clinical trials have shown that oral hygiene products containing both fluoride and arginine possess a greater anticaries effect compared with those containing fluoride alone, indicati...

  2. Primary assimilation process of triply (/sup 15/N, /sup 14/C and /sup 3/H) labeled arginine in the roots of arginine-fed barley

    Energy Technology Data Exchange (ETDEWEB)

    Mori, Satoshi [Tokyo Univ. (Japan). Faculty of Agriculture

    1981-03-01

    To clarify the mechanism of arginine utilization in barley roots, triply labeled (ureido-/sup 15/N, ureido-/sup 14/C and 5-/sup 3/H) arginine was applied to plants precultured with arginine (Arg-plants). (5-/sup 3/H) Arginine was incorporated mainly into ornithine, suggesting that arginase contributes in the first step of arginine metabolism. The arginase activity in the tissues was greatly enhanced by continuous supply of arginine, whereas urease activity was not by the same treatment. The amount of /sup 14/CO/sub 2/ evolved from (ureido-/sup 14/C) arginine in the Arg-plants was several times higher than that in plants treated with NO/sub 3//sup -/(NO/sub 3/-plants), and most /sup 14/C-urea exogenously supplied to detached roots of Arg-plants was immediately decomposed to /sup 14/CO/sub 2/. The urea released from arginine by arginase was cleaved to /sup 15/NH/sub 4//sup +/ + /sup 14/CO/sub 2/ by urease. Most of the /sup 14/CO/sub 2/ was then lost from the root system. On the other hand, the released /sup 15/NH/sub 4//sup +/ was reassimilated into amino acids probably through the pathway of ammonia assimilation. Released (5-/sup 3/H) ornithine was metabolized dominantly to proline.

  3. PRMT1-mediated arginine methylation controls ATXN2L localization

    Energy Technology Data Exchange (ETDEWEB)

    Kaehler, Christian; Guenther, Anika; Uhlich, Anja; Krobitsch, Sylvia, E-mail: krobitsc@molgen.mpg.de

    2015-05-15

    Arginine methylation is a posttranslational modification that is of importance in diverse cellular processes. Recent proteomic mass spectrometry studies reported arginine methylation of ataxin-2-like (ATXN2L), the paralog of ataxin-2, a protein that is implicated in the neurodegenerative disorder spinocerebellar ataxia type 2. Here, we investigated the methylation state of ATXN2L and its significance for ATXN2L localization. We first confirmed that ATXN2L is asymmetrically dimethylated in vivo, and observed that the nuclear localization of ATXN2L is altered under methylation inhibition. We further discovered that ATXN2L associates with the protein arginine-N-methyltransferase 1 (PRMT1). Finally, we showed that neither mutation of the arginine–glycine-rich motifs of ATXN2L nor methylation inhibition alters ATXN2L localization to stress granules, suggesting that methylation of ATXN2L is probably not mandatory. - Highlights: • ATXN2L is asymmetrically dimethylated in vivo. • ATXN2L interacts with PRMT1 under normal and stress conditions. • PRMT1-mediated dimethylation of ATXN2L controls its nuclear localization. • ATXN2L localization to stress granules appears independent of its methylation state.

  4. Spray drying of poorly soluble drugs from aqueous arginine solution.

    Science.gov (United States)

    Ojarinta, Rami; Lerminiaux, Louise; Laitinen, Riikka

    2017-10-30

    Co-amorphous drug-amino acid mixtures have shown potential for improving the solid-state stability and dissolution behavior of amorphous drugs. In previous studies, however these mixtures have been produced mainly with small-scale preparation methods, or with methods that have required the use of organic solvents or other dissolution enhancers. In the present study, co-amorphous ibuprofen-arginine and indomethacin-arginine mixtures were spray dried from water. The mixtures were prepared at two drug-arginine molar ratios (1:1 and 1:2). The properties of the prepared mixtures were investigated with differential scanning calorimetry, X-ray powder diffractometry, Fourier-transform infrared spectroscopy and a 24h, non-sink, dissolution study. All mixtures exhibited a single glass transition temperature (T g ), evidence of the formation of homogenous single-phase systems. Fourier transform infrared spectroscopy revealed strong interactions (mainly salt formation) that account for the positive deviation between measured and estimated T g values. No crystallization was observed during a 1-year stability study in either 1:1 or 1:2 mixtures, but in the presence of moisture, handling difficulties were encountered. The formation of co-amorphous salts led to improved dissolution characteristics when compared to the corresponding physical mixtures or to pure crystalline drugs. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. [l-arginine efficiency in MELAS syndrome. A case report].

    Science.gov (United States)

    Moutaouakil, F; El Otmani, H; Fadel, H; Sefrioui, F; Slassi, I

    2009-05-01

    Mitochondrial encephalomyopathy lactic acidosis and stoke-like episodes (MELAS) is a rare neurodegenerative disease caused by mutations of mitochondrial DNA. We report the case of a 12-year-old child with MELAS syndrome who presented with recurrent migraine-like headache and sudden blindness suggesting stroke-like episodes. Furthermore, he developed progressive muscular impairment with bilateral hearing loss. Serum lactate and pyruvate levels were elevated and the muscle biopsy showed an aspect of red-ragged fibers with Gomori trichrome. Brain imaging showed calcifications of basal ganglia on the CT scan and a parieto-occipital high signal on diffusion-weighted MRI. A genetic analysis was not performed but the presence of hearing loss in the patient's mother was suggestive of maternal transmission. Stroke-like episodes in the form of migraine-like headache and blindness were the patient's major complaint and did not improve despite analgesic drugs. After oral administration of l-arginine at the dose of 0.4mg/kg per day, stroke-like symptoms totally and rapidly disappeared. The efficiency of l-arginine in stroke-like episodes was initially reported then confirmed in a controlled study. The pathophysiology of stoke-like episodes and the mechanisms underlying the action of l-arginine are discussed.

  6. Arginine and proline applied as food additives stimulate high freeze tolerance in larvae of Drosophila melanogaster

    Czech Academy of Sciences Publication Activity Database

    Košťál, Vladimír; Korbelová, Jaroslava; Poupardin, Rodolphe; Moos, Martin; Šimek, Petr

    2016-01-01

    Roč. 219, č. 15 (2016), s. 2358-2367 ISSN 0022-0949 R&D Projects: GA ČR GA13-01057S EU Projects: European Commission(XE) 316304 Institutional support: RVO:60077344 Keywords : fruit fly * diet augmentation * cold tolerance Subject RIV: ED - Physiology Impact factor: 3.320, year: 2016

  7. Action of arginine for protection of ulcerative colitis by dextran sodium sulphate (DSS); Acao da arginina na protecao da colite ulcerativa induzida por sulfato de sodio dextrano

    Energy Technology Data Exchange (ETDEWEB)

    Andrade, Maria Emilia Rabelo

    2016-10-01

    Recent studies have demonstrated the benefits of immunomodulators, such as arginine, in the regulation of inflammatory responses and trophism of the intestinal mucosa. The aim of this study was to evaluate the possible mechanisms action of arginine (pretreatment or treatment) in experimental model of ulcerative colitis induced by dextran sodium sulfate (DSS). C57BL/6 mice were randomized into 5 groups: Control group (C): standard diet and water; Arginine group (ARG): diet supplementation with arginine and water; Colitis group (COL): standard diet and DSS solution; Pretreated group (PT): diet supplementation with arginine before and during colitis induction; Treated group (T): diet supplementation with arginine during colitis induction. Colitis was induced by administration of 1.5% DSS for 5 days. After this, all the mice were euthanized and blood, organs and intestinal fluid were collected for carrying out analyzes. Parameters such as intestinal permeability (IP), bacterial translocation (BT), histological analysis (histological score, morphometric analysis, collagen and mucins stain), nitrate and nitrite, cytokines and chemokines, secretory immunoglobulin A (sIgA), inflammatory infiltrate and oxidative stress were performed. The ARG group did not show difference compared to group C in the investigated parameters (C vs ARG: p> 0.05). The COL group showed increased IP (C vs COL: p < 0.05) and BT (C vs COL: p <0.05). In the histological analysis, the COL group showed severe inflammation and reduction the crypts length. In addition, in the group COL observed increase infiltration of eosinophils, neutrophils and macrophages in the colon, increase cytokine IL-17 and chemokine KC in serum and oxidative stress in the colon (COL vs C: p <0.05). In the arginine-supplemented groups (PT and T) was observed decrease IP and BT to blood, liver and lung (PT and T vs Col: p <0.05). Histological analysis showed that the arginine (PT and T) preserved the intestinal mucosa and crypts

  8. How to improve fertility of African soils? Leguminous fallows (Cameroon), addition of farmyard manure and mineral fertilizer (Kenya), organic residues management and introduction of N2 fixing species in forest plantations (Congo).

    Science.gov (United States)

    Koutika, Lydie-Stella; Mareschal, Louis; Mouanda, Cadeau; Epron, Daniel

    2014-05-01

    Most of African soils are inherently infertile and poor in nutrients mainly nitrogen and phosphorus. Several practices are used to improve soil fertility, increase productivity and ensure their sustainability. Soil fertility in the leguminous fallows was evaluated through particulate organic matter (POM), the more active part of soil organic matter (SOM) in Cameroon. The combination of mineral and organic (manure) fertilizers increased microbial P biomass allowing the release of P along the plant growing period in the Kenyan soils. Organic residues management and introduction of nitrogen fixing species (Acacia) were used to improve soil fertility and sustain forest productivity on the coastal plains of Congo. SOM fractionation was made under Pueraria, Mucuna fallows and natural regrowth mainly Chromolaena and under 3 forest plantation treatments installed in previous savanna: 1) no input, 2) normal input, and 3) double input of organic residues. Microbial P biomass and sequential P fractionation were evaluated in high and low P fixing soils. N, C, available P and pH were determined on soil sampled in acacia (100A), eucalypt (100E) and mixed-species (50A:50E) stands. N and P were determined in aboveground litters and in leaves, bark and wood of trees. The two leguminous fallows increased N content in POM fractions i.e., N >1% for Pueraria and Mucuna against Nplantations increased the soil N concentration under the mixed-species stand (N>0.06%) compared to under the pure eucalypt stand (N1% in the mixed stand and CEucalyptus stand).

  9. Graphene Functionalized with Arginine Decreases the Development of Glioblastoma Multiforme Tumor in a Gene-Dependent Manner

    Directory of Open Access Journals (Sweden)

    Ewa Sawosz

    2015-10-01

    Full Text Available Our previous studies revealed that graphene had anticancer properties in experiments in vitro with glioblastoma multiforme (GBM cells and in tumors cultured in vivo. We hypothesized that the addition of arginine or proline to graphene solutions might counteract graphene agglomeration and increase the activity of graphene. Experiments were performed in vitro with GBM U87 cells and in vivo with GBM tumors cultured on chicken embryo chorioallantoic membranes. The measurements included cell morphology, mortality, viability, tumor morphology, histology, and gene expression. The cells and tumors were treated with reduced graphene oxide (rGO and rGO functionalized with arginine (rGO + Arg or proline (rGO + Pro. The results confirmed the anticancer effect of graphene on GBM cells and tumor tissue. After functionalization with amino acids, nanoparticles were distributed more specifically, and the flakes of graphene were less agglomerated. The molecule of rGO + Arg did not increase the expression of TP53 in comparison to rGO, but did not increase the expression of MDM2 or the MDM2/TP53 ratio in the tumor, suggesting that arginine may block MDM2 expression. The expression of NQO1, known to be a strong protector of p53 protein in tumor tissue, was greatly increased. The results indicate that the complex of rGO + Arg has potential in GBM therapy.

  10. Graphene Functionalized with Arginine Decreases the Development of Glioblastoma Multiforme Tumor in a Gene-Dependent Manner

    Science.gov (United States)

    Sawosz, Ewa; Jaworski, Sławomir; Kutwin, Marta; Vadalasetty, Krishna Prasad; Grodzik, Marta; Wierzbicki, Mateusz; Kurantowicz, Natalia; Strojny, Barbara; Hotowy, Anna; Lipińska, Ludwika; Jagiełło, Joanna; Chwalibog, André

    2015-01-01

    Our previous studies revealed that graphene had anticancer properties in experiments in vitro with glioblastoma multiforme (GBM) cells and in tumors cultured in vivo. We hypothesized that the addition of arginine or proline to graphene solutions might counteract graphene agglomeration and increase the activity of graphene. Experiments were performed in vitro with GBM U87 cells and in vivo with GBM tumors cultured on chicken embryo chorioallantoic membranes. The measurements included cell morphology, mortality, viability, tumor morphology, histology, and gene expression. The cells and tumors were treated with reduced graphene oxide (rGO) and rGO functionalized with arginine (rGO + Arg) or proline (rGO + Pro). The results confirmed the anticancer effect of graphene on GBM cells and tumor tissue. After functionalization with amino acids, nanoparticles were distributed more specifically, and the flakes of graphene were less agglomerated. The molecule of rGO + Arg did not increase the expression of TP53 in comparison to rGO, but did not increase the expression of MDM2 or the MDM2/TP53 ratio in the tumor, suggesting that arginine may block MDM2 expression. The expression of NQO1, known to be a strong protector of p53 protein in tumor tissue, was greatly increased. The results indicate that the complex of rGO + Arg has potential in GBM therapy. PMID:26512645

  11. The free energy barrier for arginine gating charge translation is altered by mutations in the voltage sensor domain.

    Directory of Open Access Journals (Sweden)

    Christine S Schwaiger

    Full Text Available The gating of voltage-gated ion channels is controlled by the arginine-rich S4 helix of the voltage-sensor domain moving in response to an external potential. Recent studies have suggested that S4 moves in three to four steps to open the conducting pore, thus visiting several intermediate conformations during gating. However, the exact conformational changes are not known in detail. For instance, it has been suggested that there is a local rotation in the helix corresponding to short segments of a 3(10-helix moving along S4 during opening and closing. Here, we have explored the energetics of the transition between the fully open state (based on the X-ray structure and the first intermediate state towards channel closing (C1, modeled from experimental constraints. We show that conformations within 3 Å of the X-ray structure are obtained in simulations starting from the C1 model, and directly observe the previously suggested sliding 3(10-helix region in S4. Through systematic free energy calculations, we show that the C1 state is a stable intermediate conformation and determine free energy profiles for moving between the states without constraints. Mutations indicate several residues in a narrow hydrophobic band in the voltage sensor contribute to the barrier between the open and C1 states, with F233 in the S2 helix having the largest influence. Substitution for smaller amino acids reduces the transition cost, while introduction of a larger ring increases it, largely confirming experimental activation shift results. There is a systematic correlation between the local aromatic ring rotation, the arginine barrier crossing, and the corresponding relative free energy. In particular, it appears to be more advantageous for the F233 side chain to rotate towards the extracellular side when arginines cross the hydrophobic region.

  12. Characterisation and management of concrete grinding residuals.

    Science.gov (United States)

    Kluge, Matt; Gupta, Nautasha; Watts, Ben; Chadik, Paul A; Ferraro, Christopher; Townsend, Timothy G

    2018-02-01

    Concrete grinding residue is the waste product resulting from the grinding, cutting, and resurfacing of concrete pavement. Potential beneficial applications for concrete grinding residue include use as a soil amendment and as a construction material, including as an additive to Portland cement concrete. Concrete grinding residue exhibits a high pH, and though not hazardous, it is sufficiently elevated that precautions need to be taken around aquatic ecosystems. Best management practices and state regulations focus on reducing the impact on such aquatic environment. Heavy metals are present in concrete grinding residue, but concentrations are of the same magnitude as typically recycled concrete residuals. The chemical composition of concrete grinding residue makes it a useful product for some soil amendment purposes at appropriate land application rates. The presence of unreacted concrete in concrete grinding residue was examined for potential use as partial replacement of cement in new concrete. Testing of Florida concrete grinding residue revealed no dramatic reactivity or improvement in mortar strength.

  13. Inhibition of protein aggregation: supramolecular assemblies of arginine hold the key.

    Directory of Open Access Journals (Sweden)

    Utpal Das

    Full Text Available BACKGROUND: Aggregation of unfolded proteins occurs mainly through the exposed hydrophobic surfaces. Any mechanism of inhibition of this aggregation should explain the prevention of these hydrophobic interactions. Though arginine is prevalently used as an aggregation suppressor, its mechanism of action is not clearly understood. We propose a mechanism based on the hydrophobic interactions of arginine. METHODOLOGY: We have analyzed arginine solution for its hydrotropic effect by pyrene solubility and the presence of hydrophobic environment by 1-anilino-8-naphthalene sulfonic acid fluorescence. Mass spectroscopic analyses show that arginine forms molecular clusters in the gas phase and the cluster composition is dependent on the solution conditions. Light scattering studies indicate that arginine exists as clusters in solution. In the presence of arginine, the reverse phase chromatographic elution profile of Alzheimer's amyloid beta 1-42 (Abeta(1-42 peptide is modified. Changes in the hydrodynamic volume of Abeta(1-42 in the presence of arginine measured by size exclusion chromatography show that arginine binds to Abeta(1-42. Arginine increases the solubility of Abeta(1-42 peptide in aqueous medium. It decreases the aggregation of Abeta(1-42 as observed by atomic force microscopy. CONCLUSIONS: Based on our experimental results we propose that molecular clusters of arginine in aqueous solutions display a hydrophobic surface by the alignment of its three methylene groups. The hydrophobic surfaces present on the proteins interact with the hydrophobic surface presented by the arginine clusters. The masking of hydrophobic surface inhibits protein-protein aggregation. This mechanism is also responsible for the hydrotropic effect of arginine on various compounds. It is also explained why other amino acids fail to inhibit the protein aggregation.

  14. Inhibition of mammalian nitric oxide synthases by agmatine, an endogenous polyamine formed by decarboxylation of arginine.

    OpenAIRE

    Galea, E; Regunathan, S; Eliopoulos, V; Feinstein, D L; Reis, D J

    1996-01-01

    Agmatine, decarboxylated arginine, is a metabolic product of mammalian cells. Considering the close structural similarity between L-arginine and agmatine, we investigated the interaction of agmatine and nitric oxide synthases (NOSs), which use L-arginine to generate nitric oxide (NO) and citrulline. Brain, macrophages and endothelial cells were respectively used as sources for NOS isoforms I, II and III. Enzyme activity was measured by the production of nitrites or L-citrulline. Agmatine was ...

  15. The arginine-ornithine antiporter ArcD contributes to biological fitness of Streptococcus suis

    Directory of Open Access Journals (Sweden)

    Marcus eFulde

    2014-08-01

    Full Text Available The arginine-ornithine antiporter (ArcD is part of the Arginine Deiminase System (ADS, a catabolic, energy-providing pathway found in a variety of different bacterial species, including the porcine zoonotic pathogen Streptococcus suis. The ADS has recently been shown to play a role in the pathogenicity of S. suis, in particular in its survival in host cells. The contribution of arginine and arginine transport mediated by ArcD, however, has yet to be clarified. In the present study, we showed by experiments using [U-13C6]arginine as a tracer molecule that S. suis is auxotrophic for arginine and that bacterial growth depends on the uptake of extracellular arginine. To further study the role of ArcD in arginine metabolism, we generated an arcD-specific mutant strain and characterized its growth compared to the wild-type (WT strain, a virulent serotype 2 strain. The mutant strain showed a markedly reduced growth rate in chemically defined media supplemented with arginine when compared to the WT strain, indicating that ArcD promotes arginine uptake. To further evaluate the in vivo relevance of ArcD, we studied the intracellular bacterial survival of the arcD mutant strain in an epithelial cell culture infection model. The mutant strain was substantially attenuated, and its reduced intracellular survival rate correlated with a lower ability to neutralize the acidified environment. Based on these results, we propose that ArcD, by its function as an arginine-ornithine antiporter, is important for supplying arginine as substrate of the ADS and, thereby, contributes to biological fitness and virulence of S. suis in the host.

  16. Synthesis of the arginine labelled by {sup 15}N on the amidine group; Synthese de l'arginine marquee par {sup 15}N dans le groupe amidine

    Energy Technology Data Exchange (ETDEWEB)

    Pichat, L; Clement, J [Commissariat a l' Energie Atomique, Saclay(France). Centre d' Etudes Nucleaires

    1955-07-01

    For some biologic studies, it was necessarily to have (+) arginine marked by nitrogen 15 in the amidine group. This report describes the synthesis of the labelled arginine. The first step is the synthesis of the methyl-isourated hydro-chlorate, the intermediate reactive, from the ClNH{sub 4} isotope. The arginine is obtained from the ornithine which we previously blocked the amino group as cupric complex. The mean yield in arginine reaches 30%, based on the ammonium chloride uses. (M.B.) [French] Pour certaines etudes biologiques, il etait indispensable de disposer de (+) arginine marquee par l'azote 15 dans le groupement amidine. Ce rapport decrit la synthese de l'ariginine marquee. La premiere etape est la synthese du chlorhydrate de methylisouree, intermediaire reactif, a partir du ClNH{sub 4} isotopique. L'obtention de l'arginine est obtenue a partir de l'ornithine dont on a prealablement bloque le groupe amino sous forme de complexe cuivrique. Le rendement global moyen en arginine atteint 30 %, base sur le chlorure d'ammonium utilise. (M.B.)

  17. Structures of the N47A and E109Q mutant proteins of pyruvoyl-dependent arginine decarboxylase from Methanococcus jannaschii

    International Nuclear Information System (INIS)

    Soriano, Erika V.; McCloskey, Diane E.; Kinsland, Cynthia; Pegg, Anthony E.; Ealick, Steven E.

    2008-01-01

    The crystal structures of two arginine decarboxylase mutant proteins provide insights into the mechanisms of pyruvoyl-group formation and the decarboxylation reaction. Pyruvoyl-dependent arginine decarboxylase (PvlArgDC) catalyzes the first step of the polyamine-biosynthetic pathway in plants and some archaebacteria. The pyruvoyl group of PvlArgDC is generated by an internal autoserinolysis reaction at an absolutely conserved serine residue in the proenzyme, resulting in two polypeptide chains. Based on the native structure of PvlArgDC from Methanococcus jannaschii, the conserved residues Asn47 and Glu109 were proposed to be involved in the decarboxylation and autoprocessing reactions. N47A and E109Q mutant proteins were prepared and the three-dimensional structure of each protein was determined at 2.0 Å resolution. The N47A and E109Q mutant proteins showed reduced decarboxylation activity compared with the wild-type PvlArgDC. These residues may also be important for the autoprocessing reaction, which utilizes a mechanism similar to that of the decarboxylation reaction

  18. Nitrogen availability of biogas residues

    Energy Technology Data Exchange (ETDEWEB)

    El-Sayed Fouda, Sara

    2011-09-07

    The objectives of this study were to characterize biogas residues either unseparated or separated into a liquid and a solid phase from the fermentation of different substrates with respect to their N and C content. In addition, short and long term effects of the application of these biogas residues on the N availability and N utilization by ryegrass was investigated. It is concluded that unseparated or liquid separated biogas residues provide N at least corresponding to their ammonium content and that after the first fertilizer application the C{sub org}:N{sub org} ratio of the biogas residues was a crucial factor for the N availability. After long term application, the organic N accumulated in the soil leads to an increased release of N.

  19. L-Arginine improves multiple physiological parameters in mice exposed to diet-induced metabolic disturbances

    DEFF Research Database (Denmark)

    Clemmensen, Christoffer; Madsen, Andreas Nygaard; Smajilovic, Sanela

    2012-01-01

    L: -Arginine (L: -Arg) is a conditionally essential amino acid and a natural constituent of dietary proteins. Studies in obese rats and type 2 diabetic humans have indicated that dietary supplementation with L: -Arg can diminish gain in white adipose tissue (WAT) and improve insulin sensitivity....... However, the effects of L: -Arg on glucose homeostasis, body composition and energy metabolism remain unclear. In addition, no studies have, to our knowledge, examined whether L: -Arg has beneficial effects as a dietary supplement in the mouse model. In the present study, we investigated the effects of L...... groups. Glucose homeostasis experiments revealed a major effect of L: -Arg supplementation on glucose tolerance and insulin sensitivity, interestingly, independent of a parallel regulation in whole-body adiposity. Increased L: -Arg ingestion also raised energy expenditure; however, no concurrent effect...

  20. Oligomerization and chaperone-like activity of Drosophila melanogaster small heat shock protein DmHsp27 and three arginine mutants in the alpha-crystallin domain.

    Science.gov (United States)

    Moutaoufik, Mohamed Taha; Morrow, Geneviève; Maaroufi, Halim; Férard, Céline; Finet, Stéphanie; Tanguay, Robert M

    2017-07-01

    The small Hsp DmHsp27 from Drosophila melanogaster is one of the few small heat shock proteins (sHsps) found within the nucleus. We report that its dimerization is independent of disulfide bond formation and seems to rely on salt bridges. Unlike metazoan sHsps, DmHsp27 forms two populations of oligomers not in equilibrium. Mutations at highly conserved arginine residues in mammalian sHsps have been reported to be associated with protein conformational defects and intracellular aggregation. Independent mutation of three highly conserved arginines (R122, R131, and R135) to glycine in DmHsp27 results in only one population of higher molecular weight form. In vitro, the chaperone-like activity of wild-type DmHsp27 was comparable with that of its two isolated populations and to the single population of the R122G, R131G, and R135G using luciferase as substrate. However, using insulin, the chaperone-like activity of wild-type DmHsp27 was lower than that of R122G and R131G mutants. Altogether, the results characterize wild-type DmHsp27 and its alpha-crystallin domain (ACD) arginine mutants and may give insight into protection mechanism of sHsps.

  1. Novel photoluminescence enzyme immunoassay based on supramolecular host-guest recognition using L-arginine/6-aza-2-thiothymine-stabilized gold nanocluster.

    Science.gov (United States)

    Wang, Youmei; Lu, Minghua; Tang, Dianping

    2018-06-30

    A new photoluminescence (PL) enzyme immunoassay was designed for sensitive detection of aflatoxin B 1 (AFB 1 ) via an innovative enzyme substrate, 6-aza-2-thiothymine-stabilized gold nanocluster (AAT-AuNC) with L-arginine. The enzyme substrate with strong PL intensity was formed through supramolecular host-guest assembly between guanidine group of L-arginine and AAT capped on the surface of AuNC. Upon arginase introduction, the captured L-arginine was hydrolyzed into ornithine and urea, thus resulting in the decreasing PL intensity. Based on this principle, a novel competitive-type immunoreaction was first carried out on AFB 1 -bovine serum albumin (AFB 1 -BSA) conjugate-coated microplate, using arginase-labeled anti-AFB 1 antibody as the competitor. Under the optimum conditions, the PL intensity increased with the increment of target AFB 1 , and allowed the detection of the analyte at concentrations as low as 3.2 pg mL -1 (ppt). Moreover, L-arginine-AAT-AuNC-based PL enzyme immunoassay afforded good reproducibility and acceptable specificity. In addition, the accuracy of this methodology, referring to commercial AFB 1 ELISA kit, was evaluated to analyze naturally contaminated or spiked peanut samples, giving well-matched results between two methods, thus representing a useful scheme for practical application in quantitative monitoring of mycotoxins in foodstuff. Copyright © 2018 Elsevier B.V. All rights reserved.

  2. Efficacy of desensitizing products containing 8% arginine and calcium carbonate for hypersensitivity relief in MIH-affected molars: an 8-week clinical study.

    Science.gov (United States)

    Bekes, Katrin; Heinzelmann, Karolin; Lettner, Stefan; Schaller, Hans-Günter

    2017-09-01

    The objective of this study was to compare the efficacy in reducing hypersensitivity in molar incisor hypomineralization (MIH)-affected molars immediately and over 8 weeks combining a single in-office application and a homed-based program with desensitizing products containing 8% arginine and calcium carbonate. Nineteen children with at least one MIH-affected molar with hypersensitivity were included. Hypersensitivity was assessed with an evaporative (air) stimulus and a tactile stimulus. Each child received a single in-office treatment with a desensitizing paste containing 8% arginine and calcium carbonate (elmex Sensitive Professional desensitizing paste), followed by 8 weeks of brushing twice daily with a desensitizing toothpaste containing 8% arginine, calcium carbonate with 1450 ppm fluoride (elmex Sensitive Professional toothpaste), using the elmex Sensitive Professional toothbrush. Additionally, the corresponding mouthwash (elmex Sensitive Professional mouthwash) was used. Clinical assessments were made at baseline, immediately after the in-office treatment and after 1, 2, 4 and 8 weeks of brushing twice daily. Fifty-six molars with an air blast hypersensitivity score of 2 or 3 (Schiff Cold Air Sensitivity Scale) were included. Application of the desensitizing paste decreased hypersensitivity significantly immediately and throughout the 8 weeks recalls (p MIH. This is the first study evaluating the desensitizing effect of a desensitizing paste containing 8% arginine and calcium carbonate in patients with MIH.

  3. Effect of l-arginine therapy on plasma NO/sub 2/ and NO/sub 3/ levels, and blood pressure in uremic rabbits

    International Nuclear Information System (INIS)

    Hanif, M.; Khemomal, A.

    2011-01-01

    Background: Normal kidney function is regulated by Nitric oxide (NO) and Superoxide (O/sub 2/-) in the body, and consequently controls blood pressure. Nitric Oxide promotes natriuresis and diuresis, and therefore results in reduction of blood pressure. The objective of this study was to determine the effect of L-arginine supplementation on blood pressure, urinary protein, nitrite and nitrate in addition to blood urea, serum creatinine and creatinine clearance in uremic rabbits. Methods: This study was carried out in the Department of Biochemistry Basic Medical Sciences Institute, Jinnah Postgraduate Medical Centre, Karachi. A total of 48 rabbits were included in the study. Twenty-four of the rabbits on surgical intervention were prepared as uremic and so became hypertensive as well. Two groups were uremic, one group was given L-arginine and the other was remained untreated. Systolic and diastolic blood pressure was measured on week 0, week 2, week 4, and week 6, while blood and urine was collected on week 0 and week 6. Results: On supplementation with L-arginine to uremic rabbits systolic and diastolic blood pressures were decreased significantly. Nitrite/nitrate and urinary protein were corrected to some extent while blood urea and serum creatinine were unaffected. Conclusion: L-arginine has a beneficial role as blood pressure lowering agent in uremic rabbits. It corrects NO/sub 2/NO/sub 3/ plasma level and proteinuria which is indicator of renal failure. (author)

  4. The Influence of Arginine on the Response of Enamel Matrix Derivative (EMD Proteins to Thermal Stress: Towards Improving the Stability of EMD-Based Products.

    Directory of Open Access Journals (Sweden)

    Alessandra Apicella

    Full Text Available In a current procedure for periodontal tissue regeneration, enamel matrix derivative (EMD, which is the active component, is mixed with a propylene glycol alginate (PGA gel carrier and applied directly to the periodontal defect. Exposure of EMD to physiological conditions then causes it to precipitate. However, environmental changes during manufacture and storage may result in modifications to the conformation of the EMD proteins, and eventually premature phase separation of the gel and a loss in therapeutic effectiveness. The present work relates to efforts to improve the stability of EMD-based formulations such as Emdogain™ through the incorporation of arginine, a well-known protein stabilizer, but one that to our knowledge has not so far been considered for this purpose. Representative EMD-buffer solutions with and without arginine were analyzed by 3D-dynamic light scattering, UV-Vis spectroscopy, transmission electron microscopy and Fourier transform infrared spectroscopy at different acidic pH and temperatures, T, in order to simulate the effect of pH variations and thermal stress during manufacture and storage. The results provided evidence that arginine may indeed stabilize EMD against irreversible aggregation with respect to variations in pH and T under these conditions. Moreover, stopped-flow transmittance measurements indicated arginine addition not to suppress precipitation of EMD from either the buffers or the PGA gel carrier when the pH was raised to 7, a fundamental requirement for dental applications.

  5. Analysis of physicochemical properties of ternary systems of oxaprozin with randomly methylated-ß-cyclodextrin and l-arginine aimed to improve the drug solubility.

    Science.gov (United States)

    Mennini, Natascia; Maestrelli, Francesca; Cirri, Marzia; Mura, Paola

    2016-09-10

    The influence of l-arginine on the complexing and solubilizing power of randomly-methylated-β-cyclodextrin (RameβCD) towards oxaprozin, a very poorly soluble anti-inflammatory drug, was examined. The interactions between the components were investigated both in solution, by phase-solubility analysis, and in the solid state, by differential scanning calorimetry, FTIR and X-ray powder diffractometry. The morphology of the solid products was examined by Scanning Electron Microscopy. Results of phase-solubility studies indicated that addition of arginine enhanced the RameβCD complexing and solubilizing power of about 3.0 and 4.5 times, respectively, in comparison with the binary complex (both at pH≈6.8). The effect of arginine was not simply additive, but synergistic, being the ternary system solubility higher than the sum of those of the respective drug-CD and drug-arginine binary systems. Solid equimolar ternary systems were prepared by physical mixing, co-grinding, coevaporation and kneading techniques, to explore the effect of the preparation method on the physicochemical properties of the final products. The ternary co-ground product exhibited a dramatic increase in both drug dissolution efficiency and percent dissolved at 60min, whose values (83.6 and 97.1, respectively) were about 3 times higher than the sum of those given by the respective drug-CD and drug-aminoacid binary systems. Therefore, the ternary co-ground system with arginine and RameβCD appears as a very valuable product for the development of new more effective delivery systems of oxaprozin, with improved safety and bioavailability. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. L-Arginine Pathway in COPD Patients with Acute Exacerbation

    DEFF Research Database (Denmark)

    Ruzsics, Istvan; Nagy, Lajos; Keki, Sandor

    2016-01-01

    -performance liquid chromatography in venous blood samples and partial capillary oxygen pressure were prospectively investigated in 32 patients with COPD, 12 with AECOPD and 30 healthy subjects. RESULTS: Both ADMA and SDMA were significantly higher in AECOPD compared to stable COPD (p = 0.004 and p ....001, respectively). Oxygen content in capillaries correlated with serum ADMA concentration. However, the concentration of L-arginine was not different between AECOPD and stable COPD. Both ADMA and SDMA separated AECOPD with high sensitivity and specificity (AUC: 0.81, p = 0.001; AUC: 0.91, p

  7. Role of Arginine decarboxylase (ADC) in Arabidopsis thaliana defence against the pathogenic bacterium Pseudomonas viridiflava.

    Science.gov (United States)

    Rossi, F R; Marina, M; Pieckenstain, F L

    2015-07-01

    Polyamine biosynthesis starts with putrescine production through the decarboxylation of arginine or ornithine. In Arabidopsis thaliana, putrescine is synthesised exclusively by arginine decarboxylase (ADC), which exists as two isoforms (ADC1 and 2) that are differentially regulated by abiotic stimuli, but their role in defence against pathogens has not been studied in depth. This work analysed the participation of ADC in Arabidopsis defence against Pseudomonas viridiflava. ADC activity and expression, polyamine levels and bacterial resistance were analysed in null mutants of each ADC isoform. In non-infected wild-type (WT) plants, ADC2 expression was much higher than ADC1. Analysis of adc mutants demonstrated that ADC2 contributes to a much higher extent than ADC1 to basal ADC activity and putrescine biosynthesis. In addition, adc2 mutants showed increased basal expression of salicylic acid- and jasmonic acid-dependent PR genes. Bacterial infection induced putrescine accumulation and ADC1 expression in WT plants, but pathogen-induced putrescine accumulation was blocked in adc1 mutants. Results suggest a specific participation of ADC1 in defence, although basal resistance was not decreased by dysfunction of either of the two ADC genes. In addition, and as opposed to WT plants, bacterial infection increased ADC2 expression and ADC activity in adc1 mutants, which could counterbalance the lack of ADC1. Results demonstrate a major contribution of ADC2 to total ADC activity and the specific induction of ADC1 in response to infection. A certain degree of functional redundancy between the two isoforms in relation to their contribution to basal resistance is also evident. © 2015 German Botanical Society and The Royal Botanical Society of the Netherlands.

  8. Plasma L-arginine levels distinguish pulmonary arterial hypertension from left ventricular systolic dysfunction.

    Science.gov (United States)

    Sandqvist, Anna; Schneede, Jörn; Kylhammar, David; Henrohn, Dan; Lundgren, Jakob; Hedeland, Mikael; Bondesson, Ulf; Rådegran, Göran; Wikström, Gerhard

    2018-03-01

    Pulmonary arterial hypertension (PAH) is a life-threatening condition, characterized by an imbalance of vasoactive substances and remodeling of pulmonary vasculature. Nitric oxide, formed from L-arginine, is essential for homeostasis and smooth muscle cell relaxation in PAH. Our aim was to compare plasma concentrations of L-arginine, asymmetric dimethylarginine (ADMA), and symmetric dimethylarginine (SDMA) in PAH compared to left ventricular systolic dysfunction (LVSD) and healthy subjects. This was an observational, multicenter study comparing 21 patients with PAH to 14 patients with LVSD and 27 healthy subjects. Physical examinations were obtained and blood samples were collected. Plasma levels of ADMA, SDMA, L-arginine, L-ornithine, and L-citrulline were analyzed using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Plasma levels of ADMA and SDMA were higher, whereas L-arginine and L-arginine/ADMA ratio were lower in PAH patients compared to healthy subjects (p L-arginine than patients with LVSD (p L-Arginine correlated to 6 min walking distance (6MWD) (r s  = 0.58, p = 0.006) and L-arginine/ADMA correlated to WHO functional class (r s  = -0.46, p = 0.043) in PAH. In conclusion, L-arginine levels were significantly lower in treatment naïve PAH patients compared to patients with LVSD. Furthermore, L-arginine correlated with 6MWD in PAH. L-arginine may provide useful information in differentiating PAH from LVSD.

  9. Substitution of arginine for histidine-47 in the coenzyme binding site of yeast alcohol dehydrogenase I

    International Nuclear Information System (INIS)

    Gould, R.M.; Plapp, B.V.

    1990-01-01

    Molecular modeling of alcohol dehydrogenases suggests that His-47 in the yeast enzyme (His-44 in the protein sequence, corresponding to Arg-47 in the horse liver enzyme) binds the pyrophosphate of the NAD coenzyme. His-47 in the Saccharomyces cerevisiae isoenzyme I was substituted with an arginine by a directed mutation. Steady-state kinetic results at pH 7.3 and 30 degree C of the mutant and wild-type enzymes were consistent with an ordered Bi-Bi mechanism. The substitution decreased dissociation constants by 4-fold for NAD + and 2-fold for NADH while turnover numbers were decreased by 4-fold for ethanol oxidation and 6-fold for acetaldehyde reduction. The magnitudes of these effects are smaller than those found for the same mutation in the human liver β enzyme, suggesting that other amino acid residues in the active site modulate the effects of the substitution. The pH dependencies of dissociation constants and other kinetic constants were similar in the two yeast enzymes. Thus, it appears that His-47 is not solely responsible for a pK value near 7 that controls activity and coenzyme binding rates in the wild-type enzyme. The small substrate deuterium isotope effect above pH 7 and the single exponential phase of NADH production during the transient oxidation of ethanol by the Arg-47 enzyme suggest that the mutation makes an isomerization of the enzyme-NAD + complex limiting for turnover with ethanol

  10. Purification, cloning, and immunological characterization of arginine kinase, a novel allergen of Octopus fangsiao.

    Science.gov (United States)

    Shen, Hai-Wang; Cao, Min-Jie; Cai, Qiu-Feng; Ruan, Mi-Mi; Mao, Hai-Yan; Su, Wen-Jin; Liu, Guang-Ming

    2012-03-07

    Arginine kinase (AK) is an important enzyme participating in energy metabolism in invertebrates, but, to date, there have been no reports that AK from octopus is an allergen. In this study, octopus AK was purified, and its molecular biological, immunological, and physicochemical characterizations were analyzed. The results showed that octopus AK was purified and confirmed by mass spectrometry for the first time, and its molecular mass was 38 kDa. The full-length gene sequence of octopus AK encompassed 1209 bp and was predicted to encode a protein with 348 amino acid residues. The homology of octopus AK and crustacean AK was about 54%, but the similarity between their three-dimensional structures was high. Octopus AK could react with mouse anti-shrimp AK and rabbit anti-crab AK polyclonal antibody singly. Octopus AK could also react with specific IgE of the sera from octopus-allergic patients effectively, whereas crab AK could inhibit the reaction between them. Finally, the IgE-binding activity of octopus AK could be reduced in the processes of thermal or acid-alkali treatment. In summary, AK was identified as a novel allergen in octopus, which had a sensitizing ability similar to that of crustacean AK. This is significant in allergy diagnosis and the treatment of octopus-allergic disorders.

  11. Agmatine: multifunctional arginine metabolite and magic bullet in clinical neuroscience?

    Science.gov (United States)

    Laube, Gregor; Bernstein, Hans-Gert

    2017-07-26

    Agmatine, the decarboxylation product of arginine, was largely neglected as an important player in mammalian metabolism until the mid-1990s, when it was re-discovered as an endogenous ligand of imidazoline and α 2 -adrenergic receptors. Since then, a wide variety of agmatine-mediated effects have been observed, and consequently agmatine has moved from a wallflower existence into the limelight of clinical neuroscience research. Despite this quantum jump in scientific interest, the understanding of the anabolism and catabolism of this amine is still vague. The purification and biochemical characterization of natural mammalian arginine decarboxylase and agmatinase still are open issues. Nevertheless, the agmatinergic system is currently one of the most promising candidates in order to pharmacologically interfere with some major diseases of the central nervous system, which are summarized in the present review. Particularly with respect to major depression, agmatine, its derivatives, and metabolizing enzymes show great promise for the development of an improved treatment of this common disease. © 2017 The Author(s); published by Portland Press Limited on behalf of the Biochemical Society.

  12. PRmePRed: A protein arginine methylation prediction tool.

    Directory of Open Access Journals (Sweden)

    Pawan Kumar

    Full Text Available Protein methylation is an important Post-Translational Modification (PTMs of proteins. Arginine methylation carries out and regulates several important biological functions, including gene regulation and signal transduction. Experimental identification of arginine methylation site is a daunting task as it is costly as well as time and labour intensive. Hence reliable prediction tools play an important task in rapid screening and identification of possible methylation sites in proteomes. Our preliminary assessment using the available prediction methods on collected data yielded unimpressive results. This motivated us to perform a comprehensive data analysis and appraisal of features relevant in the context of biological significance, that led to the development of a prediction tool PRmePRed with better performance. The PRmePRed perform reasonably well with an accuracy of 84.10%, 82.38% sensitivity, 83.77% specificity, and Matthew's correlation coefficient of 66.20% in 10-fold cross-validation. PRmePRed is freely available at http://bioinfo.icgeb.res.in/PRmePRed/.

  13. The do's and don'ts of arginine supplementation | Chetty | South ...

    African Journals Online (AJOL)

    In the last three decades the nutritional and pharmacologic effects of arginine have been the subject of intense investigation. Taking into consideration the many benefits that have been demonstrated from arginine supplementation, the question remains: “Can we afford not to supplement with this immuno-nutrient”.

  14. Radioimmunoassay of [8-D-arginine] deamino-vasopressin (dDAVP)

    International Nuclear Information System (INIS)

    Slaninova, J.; Barth, T.

    1978-01-01

    Specific antibodies to [8-D-arginine] deamino-vasopressin (dDAVP) were prepared by immunizing pigs with the conjugate of [8-D-arginine] vasopressin (DVAP) and rabbit immunoglobulin. The specificity of the antibodies was studied by comparing their cross-reactivity with 20 analogues of neurohypophysial hormones. The sensitivity of the developed radioimmunoassay was 30 pg/ml. (authors)

  15. L-arginine increases nitric oxide and attenuates pressor and heart ...

    African Journals Online (AJOL)

    olayemitoyin

    heart rate responses to change in posture in sickle cell anemia subjects. 1 .... the standing position and measurements made immediately. Arterial ... pressure was the difference between systolic and diastolic ... Table 3. Effect of L-Arginine Supplementation on Blood Pressure Parameters, Plasma L-Arginine and Nitric Oxide.

  16. Synthesis, characterization and behaviour of trans-bis (argininate) copper (II) to gamma radiation

    International Nuclear Information System (INIS)

    Pereira, A.B.

    1984-01-01

    The synthesis, the characterization and the behaviour to gamma radiation of trans-bis (argininate) copper (II) are presented. The synthesis is made from copper sulfate, sodium hydroxide and hydrochloride of L (+) arginine, in aqueous medium, and the characterization by infrared spectroscopy, visible and ultraviolet spectroscopy and elementary analysis. (C.G.C.)

  17. The additional benefit of residual spraying and insecticide-treated curtains for dengue control over current best practice in Cuba: Evaluation of disease incidence in a cluster randomized trial in a low burden setting with intensive routine control.

    Science.gov (United States)

    Toledo, Maria Eugenia; Vanlerberghe, Veerle; Rosales, Julio Popa; Mirabal, Mayelin; Cabrera, Pedro; Fonseca, Viviana; Gómez Padrón, Tania; Pérez Menzies, Mirtha; Montada, Domingo; Van der Stuyft, Patrick

    2017-11-01

    Aedes control interventions are considered the cornerstone of dengue control programmes, but there is scarce evidence on their effect on disease. We set-up a cluster randomized controlled trial in Santiago de Cuba to evaluate the entomological and epidemiological effectiveness of periodical intra- and peri-domiciliary residual insecticide (deltamethrin) treatment (RIT) and long lasting insecticide treated curtains (ITC). Sixty three clusters (around 250 households each) were randomly allocated to two intervention (RIT and ITC) and one control arm. Routine Aedes control activities (entomological surveillance, source reduction, selective adulticiding, health education) were applied in the whole study area. The outcome measures were clinical dengue case incidence and immature Aedes infestation. Effectiveness of tools was evaluated using a generalized linear regression model with a negative binomial link function. Despite significant reduction in Aedes indices (Rate Ratio (RR) 0.54 (95%CI 0.32-0.89) in the first month after RIT, the effect faded out over time and dengue incidence was not reduced. Overall, in this setting there was no protective effect of RIT or ITC over routine in the 17months intervention period, with for house index RR of 1.16 (95%CI 0.96-1.40) and 1.25 (95%CI 1.03-1.50) and for dengue incidence RR of 1.43 (95%CI 1.08-1.90) and 0.96 (95%CI 0.72-1.28) respectively. The monthly dengue incidence rate (IR) at cluster level was best explained by epidemic periods (Incidence Rate Ratio (IRR) 5.50 (95%CI 4.14-7.31)), the IR in bordering houseblocks (IRR 1.03 (95%CI 1.02-1.04)) and the IR pre-intervention (IRR 1.02 (95%CI 1.00-1.04)). Adding RIT to an intensive routine Aedes control programme has a transient effect on the already moderate low entomological infestation levels, while ITC did not have any effect. For both interventions, we didn't evidence impact on disease incidence. Further studies are needed to evaluate impact in settings with high Aedes

  18. The ArcD1 and ArcD2 arginine/ornithine exchangers encoded in the arginine deiminase (ADI) pathway gene cluster of Lactococcus lactis

    NARCIS (Netherlands)

    Noens, Elke E E; Kaczmarek, Michał B; Żygo, Monika; Lolkema, Juke S

    2015-01-01

    The arginine deiminase pathway (ADI) gene cluster in Lactococcus lactis contains two copies of a gene encoding an L-arginine/L-ornithine exchanger, the arcD1 and arcD2 genes. The physiological function of ArcD1 and ArcD2 was studied by deleting the two genes. Deletion of arcD1 resulted in loss of

  19. Cell surface binding and uptake of arginine- and lysine-rich penetratin peptides in absence and presence of proteoglycans

    KAUST Repository

    Å mand, Helene L.; Rydberg, Hanna A.; Fornander, Louise H.; Lincoln, Per; Nordé n, Bengt; Esbjö rner, Elin K.

    2012-01-01

    Cell surface proteoglycans (PGs) appear to promote uptake of arginine-rich cell-penetrating peptides (CPPs), but their exact functions are unclear. To address if there is specificity in the interactions of arginines and PGs leading to improved

  20. Deciphering the Arginine-binding preferences at the substrate-binding groove of Ser/Thr kinases by computational surface mapping.

    Directory of Open Access Journals (Sweden)

    Avraham Ben-Shimon

    2011-11-01

    Full Text Available Protein kinases are key signaling enzymes that catalyze the transfer of γ-phosphate from an ATP molecule to a phospho-accepting residue in the substrate. Unraveling the molecular features that govern the preference of kinases for particular residues flanking the phosphoacceptor is important for understanding kinase specificities toward their substrates and for designing substrate-like peptidic inhibitors. We applied ANCHORSmap, a new fragment-based computational approach for mapping amino acid side chains on protein surfaces, to predict and characterize the preference of kinases toward Arginine binding. We focus on positions P-2 and P-5, commonly occupied by Arginine (Arg in substrates of basophilic Ser/Thr kinases. The method accurately identified all the P-2/P-5 Arg binding sites previously determined by X-ray crystallography and produced Arg preferences that corresponded to those experimentally found by peptide arrays. The predicted Arg-binding positions and their associated pockets were analyzed in terms of shape, physicochemical properties, amino acid composition, and in-silico mutagenesis, providing structural rationalization for previously unexplained trends in kinase preferences toward Arg moieties. This methodology sheds light on several kinases that were described in the literature as having non-trivial preferences for Arg, and provides some surprising departures from the prevailing views regarding residues that determine kinase specificity toward Arg. In particular, we found that the preference for a P-5 Arg is not necessarily governed by the 170/230 acidic pair, as was previously assumed, but by several different pairs of acidic residues, selected from positions 133, 169, and 230 (PKA numbering. The acidic residue at position 230 serves as a pivotal element in recognizing Arg from both the P-2 and P-5 positions.

  1. The role of the arginine metabolome in pain: implications for sickle cell disease

    Directory of Open Access Journals (Sweden)

    Bakshi N

    2016-03-01

    Full Text Available Nitya Bakshi,1–2 Claudia R Morris3–6 1Division of Pediatric Hematology-Oncology, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, USA; 2Aflac Cancer and Blood Disorders Center, Children’s Healthcare of Atlanta, Atlanta, GA, USA; 3Division of Pediatric Emergency Medicine, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, USA; 4Department of Emergency Medicine, Emory University School of Medicine, Atlanta, GA, USA; 5Emory-Children’s Center for Cystic Fibrosis and Airways Disease Research, Emory University School of Medicine, Atlanta, GA, USA; 6Pediatric Emergency Medicine, Children’s Healthcare of Atlanta, Atlanta, GA, USA Abstract: Sickle cell disease (SCD is the most common hemoglobinopathy in the US, affecting approximately 100,000 individuals in the US and millions worldwide. Pain is the hallmark of SCD, and a subset of patients experience pain virtually all of the time. Of interest, the arginine metabolome is associated with several pain mechanisms highlighted in this review. Since SCD is an arginine deficiency syndrome, the contribution of the arginine metabolome to acute and chronic pain in SCD is a topic in need of further attention. Normal arginine metabolism is impaired in SCD through various mechanisms that contribute to endothelial dysfunction, vaso-occlusion, pulmonary complications, risk of leg ulcers, and early mortality. Arginine is a semiessential amino acid that serves as a substrate for protein synthesis and is the precursor to nitric oxide (NO, polyamines, proline, glutamate, creatine, and agmatine. Since arginine is involved in multiple metabolic processes, a deficiency of this amino acid has the potential to disrupt many cellular and organ functions. NO is a potent vasodilator that is depleted in SCD and may contribute to vaso-occlusive pain. As the obligate substrate for NO production, arginine also plays a mechanistic role in SCD-related pain, although its

  2. Combining glial cell line-derived neurotrophic factor gene delivery (AdGDNF) with L-arginine decreases contusion size but not behavioral deficits after traumatic brain injury.

    Science.gov (United States)

    Degeorge, M L; Marlowe, D; Werner, E; Soderstrom, K E; Stock, M; Mueller, A; Bohn, M C; Kozlowski, D A

    2011-07-27

    Our laboratory has previously demonstrated that viral administration of glial cell line-derived neurotrophic factor (AdGDNF), one week prior to a controlled cortical impact (CCI) over the forelimb sensorimotor cortex of the rat (FL-SMC) is neuroprotective, but does not significantly enhance recovery of sensorimotor function. One possible explanation for this discrepancy is that although protected, neurons may not have been functional due to enduring metabolic deficiencies. Additionally, metabolic events following TBI may interfere with expression of therapeutic proteins administered to the injured brain via gene therapy. The current study focused on enhancing the metabolic function of the brain by increasing cerebral blood flow (CBF) with l-arginine in conjunction with administration of AdGDNF immediately following CCI. An adenoviral vector harboring human GDNF was injected unilaterally into FL-SMC of the rat immediately following a unilateral CCI over the FL-SMC. Within 30min of the CCI and AdGDNF injections, some animals were injected with l-arginine (i.v.). Tests of forelimb function and asymmetry were administered for 4weeks post-injury. Animals were sacrificed and contusion size and GDNF protein expression measured. This study demonstrated that rats treated with AdGDNF and l-arginine post-CCI had a significantly smaller contusion than injured rats who did not receive any treatment, or injured rats treated with either AdGDNF or l-arginine alone. Nevertheless, no amelioration of behavioral deficits was seen. These findings suggest that AdGDNF alone following a CCI was not therapeutic and although combining it with l-arginine decreased contusion size, it did not enhance behavioral recovery. Copyright © 2011 Elsevier B.V. All rights reserved.

  3. THE EFFECT OF L- ARGININE ON OXIDATIVE STRESS AND MICROALBUMINURIA IN PATIENTS WITH TYPE 2 DIABETES MELLITUS AND CHRONIC KIDNEY DISEASE

    Directory of Open Access Journals (Sweden)

    L. P. Martynyuk

    2017-07-01

    Full Text Available Background. One of the severest complications of diabetes is diabetic kidney disease (DKD. Microalbuminuria (MAU is one of the first signals of DKD and an important pathogenetic mechanism of disease progression. With diabetes dramatically antioxidant properties worsen. Objective. The aim was to investigate the effect of L-arginine on oxidative stress parameters and microalbuminuria in type 2 diabetes mellitus and chronic kidney disease patients. Methods. Total of 57 patients with type 2 diabetes mellitus and chronic kidney disease and 30 healthy subjects (control group were included in the study. The patients were divided into 2 congruent groups. The 1-st group of patients (n=33, in addition to standard therapy, received L-arginine 4.2 g intravenously for 5 days, after that they took it 1,0 g orally three times a day during meals for 1 month. The second group of patients (n=24 received a standard therapy. The concentration of lipid peroxidation products was measured by a spectrophotometric method. The determination of MAU was carried out in morning portion of urine immunological semiquantitative using test strips. Results. Significant improvement in indexes of lipid peroxidation was observed in both groups after therapy (p˂0.01, but in patients treated with L-arginine it was more expressed (p˂0,01. The standard therapy did not significantly affect the level of MAU (p˃0,05. The patients treated with L-Arginine, showed a significant reduction in MAU (p˂0.01. Conclusions. The usage of L-arginine facilitates the correction of lipid peroxidation processes and reduces the severity of microalbuminuria in patients with diabetic kidney disease that slowing its progression.

  4. The second case of a young man with L-arginine-induced acute pancreatitis.

    Science.gov (United States)

    Binet, Quentin; Dufour, Inès; Agneessens, Emmanuel; Debongnie, Jean-Claude; Aouattah, Tarik; Covas, Angélique; Coche, Jean-Charles; De Koninck, Xavier

    2018-04-21

    Dietary supplementation of arginine has been used by numerous world-class athletes and professional bodybuilders over the past 30 years. L-Arginine indeed enhances muscular power and general performance via maintaining ATP level. However, L-arginine is also known to induce acute pancreatitis in murine models. We report the case of young man presenting with upper abdominal pain and increased serum lipase levels. Contrast-enhanced computed tomography confirms a mild acute pancreatitis. Common etiologies have been ruled out and toxicological anamnestic screening reveals the intake of protein powder. This is, to the best of our knowledge, the second case in human of arginine-induced acute pancreatitis. This case report suggests that every patient presenting with acute pancreatitis without obvious etiology should be evaluated for the intake of toxics other than alcohol, including L-arginine.

  5. Potentiality of application of the conductometric L-arginine biosensors for the real sample analysis

    Directory of Open Access Journals (Sweden)

    Jaffrezic-Renault N.

    2012-12-01

    Full Text Available Aim. To determine an influence of serum components on the L-arginine biosensor sensitivity and to formulate practical recommendations for its reliable analysis. Methods. The L-arginine biosensor comprised arginase and urease co-immobilized by cross-linking. Results. The biosensor specificity was investigated based on a series of representative studies (namely, through urea determination in the serum; inhibitory effect studies of mercury ions; high temperature treatment of sensors; studying the biosensor sensitivity to the serum treated by enzymes, and selectivity studies. It was found that the response of the biosensor to the serum injections was determined by high sensitivity of the L-arginine biosensor toward not only to L-arginine but also toward two other basic amino acids (L-lysine and L-histidine. Conclusions. A detailed procedure of optimization of the conductometric biosensor for L-arginine determination in blood serum has been proposed.

  6. Effects of Aging and Tocotrienol-Rich Fraction Supplementation on Brain Arginine Metabolism in Rats

    Directory of Open Access Journals (Sweden)

    Musalmah Mazlan

    2017-01-01

    Full Text Available Accumulating evidence suggests that altered arginine metabolism is involved in the aging and neurodegenerative processes. This study sought to determine the effects of age and vitamin E supplementation in the form of tocotrienol-rich fraction (TRF on brain arginine metabolism. Male Wistar rats at ages of 3 and 21 months were supplemented with TRF orally for 3 months prior to the dissection of tissue from five brain regions. The tissue concentrations of L-arginine and its nine downstream metabolites were quantified using high-performance liquid chromatography and liquid chromatography tandem mass spectrometry. We found age-related alterations in L-arginine metabolites in the chemical- and region-specific manners. Moreover, TRF supplementation reversed age-associated changes in arginine metabolites in the entorhinal cortex and cerebellum. Multiple regression analysis revealed a number of significant neurochemical-behavioral correlations, indicating the beneficial effects of TRF supplementation on memory and motor function.

  7. Role of Renal Nerves in the Treatment of Renovascular Hypertensive Rats with L-Arginine

    Directory of Open Access Journals (Sweden)

    Sonia Alves Gouvea

    2014-01-01

    Full Text Available The purpose was to determine the role of renal nerves in mediating the effects of antihypertensive treatment with L-arginine in a renovascular hypertension model. The 2K1C (two-kidney one-clip model hypertensive rats were submitted to bilateral surgical-pharmacological renal denervation. The animals were subdivided into six experimental groups: normotensive control rats (SHAM, 2K1C rats, 2K1C rats treated with L-arginine (2K1C + L-arg, denervated normotensive (DN rats, denervated 2K1C (2K1C + DN rats, and denervated 2K1C + L-arg (2K1C + DN + L-arg rats. Arterial blood pressure, water intake, urine volume, and sodium excretion were measured. The 2K1C rats exhibited an increase in the mean arterial pressure (MAP (from 106 ± 3 to 183 ± 5.8 mmHg, P<0.01, whereas L-arg treatment induced a reduction in the MAP (143 ± 3.4 mmHg without lowering it to the control level. Renal nerve denervation reduced the MAP to normotensive levels in 2K1C rats with or without chronic L-arg treatment. L-arg and denervation induced increases in water intake and urine volume, and L-arg caused a significant natriuretic effect. Our results suggest that renal sympathetic activity participates in the genesis and the maintenance of the hypertension and also demonstrate that treatment with L-arg alone is incapable of normalizing the MAP and that the effect of such treatment is not additive with the effect of kidney denervation.

  8. Poly-L-arginine: Enhancing Cytotoxicity and Cellular Uptake of Doxorubicin and Necrotic Cell Death.

    Science.gov (United States)

    Movafegh, Bahareh; Jalal, Razieh; Mohammadi, Zobeideh; Aldaghi, Seyyede Araste

    2018-04-11

    Cell resistance to doxorubicin and its toxicity to healthy tissue reduce its efficiency. The use of cell penetrating peptides as drug delivery system along with doxorubicin is a strategy to reduce its side effects. In this study, the influence of poly-L-arginine on doxorubicin cytotoxicity, its cellular uptake and doxorubicin-induced apoptosis on human prostate cancer DU145 cells are assessed. The cytotoxicity of doxorubicin and poly-L-arginine, alone and in combination, in DU145 cells was evaluated at different exposure times using MTT assay. The influence of poly-L-arginine on doxorubicin delivery into cells was evaluated by fluorescence microscopy and ultraviolet spectroscopy. DAPI and ethidium bromide-acridine orange stainings, flow cytometry using annexin V/propidium iodide, western blot analysis with anti-p21 antibody and caspase-3 activity were used to examine the influence of poly-L-arginine on doxorubicin-induced cell death. Poly-L-arginine had no cytotoxicity at low concentrations and short exposure times. Poly-L-arginine increased the cytotoxic effect of doxorubicin in DU145 cells in a time-dependent manner. But no significant reduction was found in HFF cell viability. Poly-L-arginine seems to facilitate doxorubicin uptake and increase its intracellular concentration. 24 h combined treatment of cells with doxorubicin (0.5 μM) and poly-L-arginine (1 μg ml-1) caused a small increase in doxorubicin-induced apoptosis and significant elevated necrosis in DU145 cells as compared to each agent alone. Conlusion: Our results indicate that poly-L-arginine at lowest and highest concentrations act as proliferation-inducing and antiproliferative agents, respectively. Between these concentrations, poly-L-arginine increases the cellular uptake of doxorubicin and its cytotoxicity through induction of necrosis. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  9. Effects of carbohydrate, branched-chain amino acids, and arginine in recovery period on the subsequent performance in wrestlers

    Directory of Open Access Journals (Sweden)

    Jang Tsong-Rong

    2011-11-01

    Full Text Available Abstract Many athletes need to participate in multiple events in a single day. The efficient post-exercise glycogen recovery may be critical for the performance in subsequent exercise. This study examined whether post-exercise carbohydrate supplementation could restore the performance in the subsequent simulated wrestling match. The effect of branched-chain amino acids and arginine on glucose disposal and performance was also investigated. Nine well-trained male wrestlers participated in 3 trials in a random order. Each trial contained 3 matches with a 1-hr rest between match 1 and 2, and a 2-hr rest between match 2 and 3. Each match contained 3 exercise periods interspersed with 1-min rests. The subjects alternated 10-s all-out sprints and 20-s rests in each exercise period. At the end of match 2, 3 different supplementations were consumed: 1.2 g/kg glucose (CHO trial, 1 g/kg glucose + 0.1 g/kg Arg + 0.1 g/kg BCAA (CHO+AA trial, or water (placebo trial. The peak and average power in the 3 matches was similar in the 3 trials. After the supplementation, CHO and CHO+AA trial showed significantly higher glucose and insulin, and lower glycerol and non-esterified fatty acid concentrations than the placebo trial. There was no significant difference in these biochemical parameters between the CHO and CHO+AA trials. Supplementation of carbohydrate with or without BCAA and arginine during the post-match period had no effect on the performance in the following simulated match in wrestlers. In addition, BCAA and arginine did not provide additional insulinemic effect.

  10. Effects of Mutations and Ligands on the Thermostability of the l-Arginine/Agmatine Antiporter AdiC and Deduced Insights into Ligand-Binding of Human l-Type Amino Acid Transporters

    Directory of Open Access Journals (Sweden)

    Hüseyin Ilgü

    2018-03-01

    Full Text Available The l-arginine/agmatine transporter AdiC is a prokaryotic member of the SLC7 family, which enables pathogenic enterobacteria to survive the extremely acidic gastric environment. Wild-type AdiC from Escherichia coli, as well as its previously reported point mutants N22A and S26A, were overexpressed homologously and purified to homogeneity. A size-exclusion chromatography-based thermostability assay was used to determine the melting temperatures (Tms of the purified AdiC variants in the absence and presence of the selected ligands l-arginine (Arg, agmatine, l-arginine methyl ester, and l-arginine amide. The resulting Tms indicated stabilization of AdiC variants upon ligand binding, in which Tms and ligand binding affinities correlated positively. Considering results from this and previous studies, we revisited the role of AdiC residue S26 in Arg binding and proposed interactions of the α-carboxylate group of Arg exclusively with amide groups of the AdiC backbone. In the context of substrate binding in the human SLC7 family member l-type amino acid transporter-1 (LAT1; SLC7A5, an analogous role of S66 in LAT1 to S26 in AdiC is discussed based on homology modeling and amino acid sequence analysis. Finally, we propose a binding mechanism for l-amino acid substrates to LATs from the SLC7 family.

  11. Effects of Mutations and Ligands on the Thermostability of the l-Arginine/Agmatine Antiporter AdiC and Deduced Insights into Ligand-Binding of Human l-Type Amino Acid Transporters.

    Science.gov (United States)

    Ilgü, Hüseyin; Jeckelmann, Jean-Marc; Colas, Claire; Ucurum, Zöhre; Schlessinger, Avner; Fotiadis, Dimitrios

    2018-03-20

    The l-arginine/agmatine transporter AdiC is a prokaryotic member of the SLC7 family, which enables pathogenic enterobacteria to survive the extremely acidic gastric environment. Wild-type AdiC from Escherichia coli, as well as its previously reported point mutants N22A and S26A, were overexpressed homologously and purified to homogeneity. A size-exclusion chromatography-based thermostability assay was used to determine the melting temperatures ( T m s) of the purified AdiC variants in the absence and presence of the selected ligands l-arginine (Arg), agmatine, l-arginine methyl ester, and l-arginine amide. The resulting T m s indicated stabilization of AdiC variants upon ligand binding, in which T m s and ligand binding affinities correlated positively. Considering results from this and previous studies, we revisited the role of AdiC residue S26 in Arg binding and proposed interactions of the α-carboxylate group of Arg exclusively with amide groups of the AdiC backbone. In the context of substrate binding in the human SLC7 family member l-type amino acid transporter-1 (LAT1; SLC7A5), an analogous role of S66 in LAT1 to S26 in AdiC is discussed based on homology modeling and amino acid sequence analysis. Finally, we propose a binding mechanism for l-amino acid substrates to LATs from the SLC7 family.

  12. Altered Nitrogen Balance and Decreased Urea Excretion in Male Rats Fed Cafeteria Diet Are Related to Arginine Availability

    Directory of Open Access Journals (Sweden)

    David Sabater

    2014-01-01

    rats, but low arginine levels point to a block in the urea cycle between ornithine and arginine, thereby preventing the elimination of excess nitrogen as urea. The ultimate consequence of this paradoxical block in the urea cycle seems to be the limitation of arginine production and/or availability.

  13. Bioenergy from sisal residues

    Energy Technology Data Exchange (ETDEWEB)

    Jungersen, G. [Dansk Teknologisk Inst. (Denmark); Kivaisi, A.; Rubindamayugi, M. [Univ. of Dar es Salaam (Tanzania, United Republic of)

    1998-05-01

    The main objectives of this report are: To analyse the bioenergy potential of the Tanzanian agro-industries, with special emphasis on the Sisal industry, the largest producer of agro-industrial residues in Tanzania; and to upgrade the human capacity and research potential of the Applied Microbiology Unit at the University of Dar es Salaam, in order to ensure a scientific and technological support for future operation and implementation of biogas facilities and anaerobic water treatment systems. The experimental work on sisal residues contains the following issues: Optimal reactor set-up and performance; Pre-treatment methods for treatment of fibre fraction in order to increase the methane yield; Evaluation of the requirement for nutrient addition; Evaluation of the potential for bioethanol production from sisal bulbs. The processing of sisal leaves into dry fibres (decortication) has traditionally been done by the wet processing method, which consumes considerable quantities of water and produces large quantities of waste water. The Tanzania Sisal Authority (TSA) is now developing a dry decortication method, which consumes less water and produces a waste product with 12-15% TS, which is feasible for treatment in CSTR systems (Continously Stirred Tank Reactors). (EG)

  14. Collision-Induced Dissociation of Deprotonated Peptides. Relative Abundance of Side-Chain Neutral Losses, Residue-Specific Product Ions, and Comparison with Protonated Peptides.

    Science.gov (United States)

    Liang, Yuxue; Neta, Pedatsur; Yang, Xiaoyu; Stein, Stephen E

    2018-03-01

    High-accuracy MS/MS spectra of deprotonated ions of 390 dipeptides and 137 peptides with three to six residues are studied. Many amino acid residues undergo neutral losses from their side chains. The most abundant is the loss of acetaldehyde from threonine. The abundance of losses from the side chains of other amino acids is estimated relative to that of threonine. While some amino acids lose the whole side chain, others lose only part of it, and some exhibit two or more different losses. Side-chain neutral losses are less abundant in the spectra of protonated peptides, being significant mainly for methionine and arginine. In addition to the neutral losses, many amino acid residues in deprotonated peptides produce specific negative ions after peptide bond cleavage. An expanded list of fragment ions from protonated peptides is also presented and compared with those of deprotonated peptides. Fragment ions are mostly different for these two cases. These lists of fragments are used to annotate peptide mass spectral libraries and to aid in the confirmation of specific amino acids in peptides. Graphical Abstract ᅟ.

  15. Characterization of casein and poly-l-arginine multilayer films

    Science.gov (United States)

    Szyk-Warszyńska, Lilianna; Kilan, Katarzyna; Socha, Robert P.

    2014-06-01

    Thin films containing casein appear to be a promising material for coatings used in the medical area to promote biomineralization. alfa- and beta-casein and poly-L-arginine multilayer films were formed by the layer-by layer technique and their thickness and mass were analyzed by ellipsometry and quartz crystal microbalance with dissipation monitoring (QCM-D). We investigated the effect of the type of casein used for the film formation and of the polyethyleneimine anchoring layer on the thickness and mass of adsorbed films. The analysis of the mass of films during their post-treatment with the solutions of various ionic strength and pH provided the information concerning films stability, while the XPS elemental analysis confirmed binding of calcium ions by the casein embedded in the multilayers.

  16. Microwave heating of arginine yields highly fluorescent nanoparticles

    International Nuclear Information System (INIS)

    Philippidis, Aggelos; Stefanakis, Dimitrios; Anglos, Demetrios; Ghanotakis, Demetrios

    2013-01-01

    Brightly fluorescent nanoparticles were produced via a single-step, single-precursor procedure based on microwave heating of an aqueous solution of the amino acid arginine. Key structural and optical properties of the resulting Arg nanoparticles, Arg-dots, are reported and discussed with emphasis on the pH dependence of their fluorescence emission. The surface of the Arg-dots was functionalised through coupling to folic acid, opening up ways for connecting fluorescent nanoparticles to cancer cells. The generality and versatility of the microwave heating procedure was further demonstrated by the synthesis of different types of carbon nanoparticles, such as CE-dots, that were produced by use of citric acid and ethanolamine as precursors and compared to the Arg-dots.

  17. Residuals Management and Water Pollution Control Planning.

    Science.gov (United States)

    Environmental Protection Agency, Washington, DC. Office of Public Affairs.

    This pamphlet addresses the problems associated with residuals and water quality especially as it relates to the National Water Pollution Control Program. The types of residuals and appropriate management systems are discussed. Additionally, one section is devoted to the role of citizen participation in developing management programs. (CS)

  18. Additive manufacturing.

    Science.gov (United States)

    Mumith, A; Thomas, M; Shah, Z; Coathup, M; Blunn, G

    2018-04-01

    Increasing innovation in rapid prototyping (RP) and additive manufacturing (AM), also known as 3D printing, is bringing about major changes in translational surgical research. This review describes the current position in the use of additive manufacturing in orthopaedic surgery. Cite this article: Bone Joint J 2018;100-B:455-60.

  19. Clinical Outcome And Arginine Serum of Acute Ischemic Stroke Patients Supplemented by Snakehead Fish Extract

    Science.gov (United States)

    Pudjonarko, Dwi; Retnaningsih; Abidin, Zainal

    2018-02-01

    Background: Levels of arginine associated with clinical outcome in acute ischemic stroke (AIS). Arginine is a protein needed to synthesis nitric oxide (NO), a potential vasodilator and antioxidant. Snakehead fish is a source of protein which has antioxidant activity. Snakehead fish contains mineral, vitamin, and amino acids. One of the amino acids that were found quite high in snakehead fish extract is arginine. The aim of this study was done to determine the effect of snakehead fish extracts (SFE) on serum arginin levels and clinical outcome of AIS patients. Methods: It was double-blind randomized pretest-posttest control group design, with. AIS patients were divided into two groups i.e. snakehead fish extracts (SFE) and control. SFE group were administered 15 grams SFE for 7 days . Arginine serum levels and clinical outcome (measured by National Institute of Health Stroke Scale = NIHSS) were measured before and after treatment, other related factors were also analyzed in Logistic regression. Results: A total of 42 subjects who were performed random allocation as SFE or control group. There was no differences in subject characteristics between the two groups. There was a differences Δ arginine serum levels between SFE and control (33.6±19.95 μmol/L 0.3±2.51 μmol/L pgender factor that affected on improvement of NIHSS (OR=7; p=0,01). Conclusion: There is Clinical outcome improvement and enhancement of arginine serum levels in AIS patient with snakehead fish extract supplementation.

  20. Arginine as an adjuvant to chemotherapy improves clinical outcome in active tuberculosis

    DEFF Research Database (Denmark)

    Schön, T; Elias, D; Moges, F

    2003-01-01

    , and clinical symptoms after week 8. Secondary outcomes were sedimentation rate and levels of NO metabolites, arginine, citrulline, and tumour necrosis factor-a. Compared with the human immunodeficiency virus (HIV)-/TB+ placebo group, the HIV-/TB+ patients in the arginine group showed significant improvement......, defined as increased weight gain, higher sputum conversion rate and faster reduction of symptoms, such as cough. The arginine level increased after week 2 in the HIV-/TB+ arginine group (100.2 microM (range 90.5-109.9) versus 142.1 microM (range 114.1-170.1)) compared with the HIV-/TB+ placebo group (105.......5 microM (range 93.7-117.3) versus 95.7 microM (range 82.4-108.9)). HIV seroprevalence was 52.5%. No clinical improvement or increase in serum arginine was detected in arginine supplemented HIV+/TB+ patients compared with placebo. Arginine is beneficial as an adjuvant treatment in human immunodeficiency...

  1. Quantitative phosphoproteomics reveals the role of protein arginine phosphorylation in the bacterial stress response.

    Science.gov (United States)

    Schmidt, Andreas; Trentini, Débora Broch; Spiess, Silvia; Fuhrmann, Jakob; Ammerer, Gustav; Mechtler, Karl; Clausen, Tim

    2014-02-01

    Arginine phosphorylation is an emerging protein modification implicated in the general stress response of Gram-positive bacteria. The modification is mediated by the arginine kinase McsB, which phosphorylates and inactivates the heat shock repressor CtsR. In this study, we developed a mass spectrometric approach accounting for the peculiar chemical properties of phosphoarginine. The improved methodology was used to analyze the dynamic changes in the Bacillus subtilis arginine phosphoproteome in response to different stress situations. Quantitative analysis showed that a B. subtilis mutant lacking the YwlE arginine phosphatase accumulated a strikingly large number of arginine phosphorylations (217 sites in 134 proteins), however only a minor fraction of these sites was increasingly modified during heat shock or oxidative stress. The main targets of McsB-mediated arginine phosphorylation comprise central factors of the stress response system including the CtsR and HrcA heat shock repressors, as well as major components of the protein quality control system such as the ClpCP protease and the GroEL chaperonine. These findings highlight the impact of arginine phosphorylation in orchestrating the bacterial stress response.

  2. Renal response to L-arginine in diabetic rats. A possible link between nitric oxide system and aquaporin-2.

    Directory of Open Access Journals (Sweden)

    María C Ortiz

    Full Text Available The aim of this study was to evaluate whether L-Arginine (L-Arg supplementation modifies nitric oxide (NO system and consequently aquaporin-2 (AQP2 expression in the renal outer medulla of streptozotocin-diabetic rats at an early time point after induction of diabetes. Male Wistar rats were divided in four groups: Control, Diabetic, Diabetic treated with L-Arginine and Control treated with L-Arginine. Nitric oxide synthase (NOS activity was estimated by [14C] L-citrulline production in homogenates of the renal outer medulla and by NADPH-diaphorase staining in renal outer medullary tubules. Western blot was used to detect the expression of AQP2 and NOS types I and III; real time PCR was used to quantify AQP2 mRNA. The expression of both NOS isoforms, NOS I and NOS III, was decreased in the renal outer medulla of diabetic rats and L-Arg failed to prevent these decreases. However, L-Arg improved NO production, NADPH-diaphorase activity in collecting ducts and other tubular structures, and NOS activity in renal homogenates from diabetic rats. AQP2 protein and mRNA were decreased in the renal outer medulla of diabetic rats and L-Arg administration prevented these decreases. These results suggest that the decreased NOS activity in collecting ducts of the renal outer medulla may cause, at least in part, the decreased expression of AQP2 in this model of diabetes and constitute additional evidence supporting a role for NO in contributing to renal water reabsorption through the modulation of AQP2 expression in this pathological condition. However, we cannot discard that another pathway different from NOS also exists that links L-Arg to AQP2 expression.

  3. Hepatic adaptation compensates inactivation of intestinal arginine biosynthesis in suckling mice.

    Directory of Open Access Journals (Sweden)

    Vincent Marion

    Full Text Available Suckling mammals, including mice, differ from adults in the abundant expression of enzymes that synthesize arginine from citrulline in their enterocytes. To investigate the importance of the small-intestinal arginine synthesis for whole-body arginine production in suckling mice, we floxed exon 13 of the argininosuccinate synthetase (Ass gene, which codes for a key enzyme in arginine biosynthesis, and specifically and completely ablated Ass in enterocytes by crossing Ass (fl and Villin-Cre mice. Unexpectedly, Ass (fl/fl /VilCre (tg/- mice showed no developmental impairments. Amino-acid fluxes across the intestine, liver, and kidneys were calculated after determining the blood flow in the portal vein, and hepatic and renal arteries (86%, 14%, and 33%, respectively, of the transhepatic blood flow in 14-day-old mice. Relative to control mice, citrulline production in the splanchnic region of Ass (fl/fl /VilCre (tg/- mice doubled, while arginine production was abolished. Furthermore, the net production of arginine and most other amino acids in the liver of suckling control mice declined to naught or even changed to consumption in Ass (fl/fl /VilCre (tg/- mice, and had, thus, become remarkably similar to that of post-weaning wild-type mice, which no longer express arginine-biosynthesizing enzymes in their small intestine. The adaptive changes in liver function were accompanied by an increased expression of genes involved in arginine metabolism (Asl, Got1, Gpt2, Glud1, Arg1, and Arg2 and transport (Slc25a13, Slc25a15, and Slc3a2, whereas no such changes were found in the intestine. Our findings suggest that the genetic premature deletion of arginine synthesis in enterocytes causes a premature induction of the post-weaning pattern of amino-acid metabolism in the liver.

  4. Atropine and ODQ antagonize tetanic fade induced by L-arginine in cats

    Directory of Open Access Journals (Sweden)

    J.M. Cruciol-Souza

    1999-10-01

    Full Text Available Although it has been demonstrated that nitric oxide (NO released from sodium nitrite induces tetanic fade in the cat neuromuscular preparations, the effect of L-arginine on tetanic fade and its origin induced by NO have not been studied in these preparations. Furthermore, atropine reduces tetanic fade induced by several cholinergic and anticholinergic drugs in these preparations, whose mechanism is suggested to be mediated by the interaction of acetylcholine with inhibitory presynaptic muscarinic receptors. The present study was conducted in cats to determine the effects of L-arginine alone or after pretreatment with atropine or 1H-[1,2,4]oxadiazole [4,3-a]quinoxalin-1-one (ODQ on neuromuscular preparations indirectly stimulated at high frequency. Drugs were injected into the middle genicular artery. L-arginine (2 mg/kg and S-nitroso-N-acetylpenicillamine (SNAP; 16 µg/kg induced tetanic fade. The Nw-nitro-L-arginine (L-NOARG; 2 mg/kg alone did not produce any effect, but reduced the tetanic fade induced by L-arginine. D-arginine (2 mg/kg did not induce changes in tetanic fade. The tetanic fade induced by L-arginine or SNAP was reduced by previous injection of atropine (1.0 µg/kg or ODQ (15 µg/kg. ODQ alone did not change tetanic fade. The data suggest that the NO-synthase-GC pathway participates in the L-arginine-induced tetanic fade in cat neuromuscular preparations. The tetanic fade induced by L-arginine probably depends on the action of NO at the presynaptic level. NO may stimulate guanylate cyclase increasing acetylcholine release and thereby stimulating presynaptic muscarinic receptors.

  5. PRE-EXERCISE ARGININE SUPPLEMENTATION INCREASES TIME TO EXHAUSTION IN ELITE MALE WRESTLERS

    Directory of Open Access Journals (Sweden)

    H.U. Yavuz

    2014-08-01

    Full Text Available Dietary supplements containing arginine are among the most popular ergogenics intended to enhance strength, power and muscle recovery associated with both anaerobic and aerobic exercise. The aim of the present study was to evaluate the possible effect of pre-exercise acute intake of arginine on performance and exercise metabolism during incremental exhaustive exercise in elite male wrestlers. Nine volunteer elite male wrestlers (24.7±3.8 years participated in this study. The test-retest protocol was used on the same subjects. The study was conducted using a cross-over design. A single dose of arginine (1.5 g · 10 kg-1 body weight or placebo was given to the subjects after 12 hours fasting (during the night for both test and retest. Subjects were allowed to drink water but not allowed to eat anything between arginine or placebo ingestion and the exercise protocol. An incremental exercise protocol was applied and oxygen consumption was measured during the exercise. Heart rate and plasma lactate levels were measured during the exercise and recovery. Results showed that in the same working loads there was no significant difference for the mean lactate levels and no difference in maximum oxygen consumption (arginine 52.47±4.01 mL · kg-1 · min-1, placebo 52.07±5.21 mL · kg-1 · min-1 or in maximum heart rates (arginine 181.09±13.57 bpm, placebo 185.89±7.38 bpm between arginine and placebo trials. Time to exhaustion was longer with arginine supplementation (1386.8±69.8 s compared to placebo (1313±90.8 s (p<0.05. These results suggest that L-arginine supplementation can have beneficial effects on exercise performance in elite male wrestlers but cannot explain the metabolic pathways which are responsible from these effects.

  6. Alterations in plasma L-arginine and methylarginines in heart failure and after heart transplantation.

    Science.gov (United States)

    Lundgren, Jakob; Sandqvist, Anna; Hedeland, Mikael; Bondesson, Ulf; Wikström, Gerhard; Rådegran, Göran

    2018-04-12

    Endothelial function, including the nitric oxide (NO)-pathway, has previously been extensively investigated in heart failure (HF). In contrast, studies are lacking on the NO pathway after heart transplantation (HT). We therefore investigated substances in the NO pathway prior to and after HT in relation to hemodynamic parameters. 12 patients (median age 50.0 yrs, 2 females), heart transplanted between June 2012 and February 2014, evaluated at our hemodynamic lab, at rest, prior to HT, as well as four weeks and six months after HT were included. All patients had normal left ventricular function post-operatively and none had post-operative pulmonary hypertension or acute cellular rejection requiring therapy at the evaluations. Plasma concentrations of ADMA, SDMA, L-Arginine, L-Ornithine and L-Citrulline were analyzed at each evaluation. In comparison to controls, the plasma L-Arginine concentration was low and ADMA high in HF patients, resulting in low L-Arginine/ADMA-ratio pre-HT. Already four weeks after HT L-Arginine was normalized whereas ADMA remained high. Consequently the L-Arginine/ADMA-ratio improved, but did not normalize. The biomarkers remained unchanged at the six-month evaluation and the L-Arginine/ADMA-ratio correlated inversely to pulmonary vascular resistance (PVR) six months post-HT. Plasma L-Arginine concentrations normalize after HT. However, as ADMA is unchanged, the L-Arginine/ADMA-ratio remained low and correlated inversely to PVR. Together these findings suggest that (i) the L-Arginine/ADMA-ratio may be an indicator of pulmonary vascular tone after HT, and that (ii) NO-dependent endothelial function is partly restored after HT. Considering the good postoperative outcome, the biomarker levels may be considered "normal" after HT.

  7. Food additives

    Science.gov (United States)

    ... GO About MedlinePlus Site Map FAQs Customer Support Health Topics Drugs & Supplements Videos & Tools Español You Are Here: Home → Medical Encyclopedia → Food additives URL of this page: //medlineplus.gov/ency/article/ ...

  8. Negative argininosuccinate synthetase expression in melanoma tumours may predict clinical benefit from arginine-depleting therapy with pegylated arginine deiminase

    Science.gov (United States)

    Feun, L G; Marini, A; Walker, G; Elgart, G; Moffat, F; Rodgers, S E; Wu, C J; You, M; Wangpaichitr, M; Kuo, M T; Sisson, W; Jungbluth, A A; Bomalaski, J; Savaraj, N

    2012-01-01

    Background: Arginine-depleting therapy with pegylated arginine deiminase (ADI-PEG20) was reported to have activity in advanced melanoma in early phase I–II trial, and clinical trials are currently underway in other cancers. However, the optimal patient population who benefit from this treatment is unknown. Methods: Advanced melanoma patients with accessible tumours had biopsy performed before the start of treatment with ADI-PEG20 and at the time of progression or relapse when amenable to determine whether argininosuccinate synthetase (ASS) expression in tumour was predictive of response to ADI-PEG20. Results: Twenty-seven of thirty-eight patients treated had melanoma tumours assessable for ASS staining before treatment. Clinical benefit rate (CBR) and longer time to progression were associated with negative expression of tumour ASS. Only 1 of 10 patients with ASS-positive tumours (ASS+) had stable disease, whereas 4 of 17 (24%) had partial response and 5 had stable disease, when ASS expression was negative (ASS−), giving CBR rates of 52.9 vs 10%, P=0.041. Two responding patients with negative ASS expression before therapy had rebiopsy after tumour progression and the ASS expression became positive. The survival of ASS− patients receiving at least four doses at 320 IU m−2 was significantly better than the ASS+ group at 26.5 vs 8.5 months, P=0.024. Conclusion: ADI-PEG20 is safe and the drug is only efficacious in melanoma patients whose tumour has negative ASS expression. Argininosuccinate synthetase tumour positivity is associated with drug resistance and tumour progression. PMID:22472884

  9. Participation of the arcRACME protein in self-activation of the arc operon located in the arginine catabolism mobile element in pandemic clone USA300.

    Science.gov (United States)

    Rozo, Zayda Lorena Corredor; Márquez-Ortiz, Ricaurte Alejandro; Castro, Betsy Esperanza; Gómez, Natasha Vanegas; Escobar-Pérez, Javier

    2017-07-01

    Staphylococcus aureus pandemic clone USA300 has, in addition to its constitutive arginine catabolism (arc) gene cluster, an arginine catabolism mobile element (ACME) carrying another such cluster, which gives this clone advantages in colonisation and infection. Gene arcR, which encodes an oxygen-sensitive transcriptional regulator, is inside ACME and downstream of the constitutive arc gene cluster, and this situation may have an impact on its activation. Different relative expression behaviours are proven here for arcRACME and the arcACME operon compared to the constitutive ones. We also show that the artificially expressed recombinant ArcRACME protein binds to the promoter region of the arcACME operon; this mechanism can be related to a positive feedback model, which may be responsible for increased anaerobic survival of the USA300 clone during infection-related processes.

  10. Protein arginine methyltransferase 5 functions as an epigenetic activator of the androgen receptor to promote prostate cancer cell growth.

    Science.gov (United States)

    Deng, X; Shao, G; Zhang, H-T; Li, C; Zhang, D; Cheng, L; Elzey, B D; Pili, R; Ratliff, T L; Huang, J; Hu, C-D

    2017-03-02

    Protein arginine methyltransferase 5 (PRMT5) is an emerging epigenetic enzyme that mainly represses transcription of target genes via symmetric dimethylation of arginine residues on histones H4R3, H3R8 and H2AR3. Accumulating evidence suggests that PRMT5 may function as an oncogene to drive cancer cell growth by epigenetic inactivation of several tumor suppressors. Here, we provide evidence that PRMT5 promotes prostate cancer cell growth by epigenetically activating transcription of the androgen receptor (AR) in prostate cancer cells. Knockdown of PRMT5 or inhibition of PRMT5 by a specific inhibitor reduces the expression of AR and suppresses the growth of multiple AR-positive, but not AR-negative, prostate cancer cells. Significantly, knockdown of PRMT5 in AR-positive LNCaP cells completely suppresses the growth of xenograft tumors in mice. Molecular analysis reveals that PRMT5 binds to the proximal promoter region of the AR gene and contributes mainly to the enriched symmetric dimethylation of H4R3 in the same region. Mechanistically, PRMT5 is recruited to the AR promoter by its interaction with Sp1, the major transcription factor responsible for AR transcription, and forms a complex with Brg1, an ATP-dependent chromatin remodeler, on the proximal promoter region of the AR gene. Furthermore, PRMT5 expression in prostate cancer tissues is significantly higher than that in benign prostatic hyperplasia tissues, and PRMT5 expression correlates positively with AR expression at both the protein and mRNA levels. Taken together, our results identify PRMT5 as a novel epigenetic activator of AR in prostate cancer. Given that inhibiting AR transcriptional activity or androgen synthesis remains the major mechanism of action for most existing anti-androgen agents, our findings also raise an interesting possibility that targeting PRMT5 may represent a novel approach for prostate cancer treatment by eliminating AR expression.

  11. Asymmetric dimethyl-L-arginine (ADMA): a possible link between homocyst(e)ine and endothelial dysfunction.

    Science.gov (United States)

    Stühlinger, Markus C; Stanger, Olaf

    2005-02-01

    Hyperhomocyst(e)inemia is associated with an increased risk for atherosclerotic disease and venous thromboembolism. The impact of elevated plasma homocysteine levels seems to be clinically relevant, since the total cardiovascular risk of hyperhomocyst(e)inemia is comparable to the risk associated with hyperlipidemia or smoking. There is substantial evidence for impairment of endothelial function in human and animal models of atherosclerosis, occurring even before development of overt plaques. Interestingly endothelial dysfunction appears to be a sensitive indicator of the process of atherosclerotic lesion development and predicts future vascular events. NO is the most potent endogenous vasodilator known. It is released by the endothelium, and reduced NO bioavailability is responsible for impaired endothelium-dependent vasorelaxation in hyperhomocyst(e)inemia and other metabolic disorders associated with vascular disease. Substances leading to impaired endothelial function as a consequence of reduced NO generation are endogenous NO synthase inhibitors such as ADMA. Indeed there is accumulating evidence from animal and human studies that ADMA, endothelial function and homocyst(e)ine might be closely interrelated. Specifically elevations of ADMA associated with impaired endothelium-dependent relaxation were found in chronic hyperhomocyst(e)inemia, as well as after acute elevation of plasma homocyst(e)ine following oral methionine intake. The postulated mechanisms for ADMA accumulation are increased methylation of arginine residues within proteins, as well as reduced metabolism of ADMA by the enzyme DDAH, but they still need to be confirmed to be operative in vivo. Hyperhomocyst(e)inemia, as well as subsequent endothelial dysfunction can be successfully treated by application of folate and B vitamins. Since ADMA seems to play a central role in homocyst(e)ine-induced endothelial dysfunction, another way of preventing vascular disease in patients with elevated homocyst

  12. Serum stabilities of short tryptophan- and arginine-rich antimicrobial peptide analogs.

    Directory of Open Access Journals (Sweden)

    Leonard T Nguyen

    2010-09-01

    Full Text Available Several short antimicrobial peptides that are rich in tryptophan and arginine residues were designed with a series of simple modifications such as end capping and cyclization. The two sets of hexapeptides are based on the Trp- and Arg-rich primary sequences from the "antimicrobial centre" of bovine lactoferricin as well as an antimicrobial sequence obtained through the screening of a hexapeptide combinatorial library.HPLC, mass spectrometry and antimicrobial assays were carried out to explore the consequences of the modifications on the serum stability and microbicidal activity of the peptides. The results show that C-terminal amidation increases the antimicrobial activity but that it makes little difference to its proteolytic degradation in human serum. On the other hand, N-terminal acetylation decreases the peptide activities but significantly increases their protease resistance. Peptide cyclization of the hexameric peptides was found to be highly effective for both serum stability and antimicrobial activity. However the two cyclization strategies employed have different effects, with disulfide cyclization resulting in more active peptides while backbone cyclization results in more proteolytically stable peptides. However, the benefit of backbone cyclization did not extend to longer 11-mer peptides derived from the same region of lactoferricin. Mass spectrometry data support the serum stability assay results and allowed us to determine preferred proteolysis sites in the peptides. Furthermore, isothermal titration calorimetry experiments showed that the peptides all had weak interactions with albumin, the most abundant protein in human serum.Taken together, the results provide insight into the behavior of the peptides in human serum and will therefore aid in advancing antimicrobial peptide design towards systemic applications.

  13. Maternal melatonin or N-acetylcysteine therapy regulates hydrogen sulfide-generating pathway and renal transcriptome to prevent prenatal NG-Nitro-L-arginine-methyl ester (L-NAME)-induced fetal programming of hypertension in adult male offspring.

    Science.gov (United States)

    Tain, You-Lin; Lee, Chien-Te; Chan, Julie Y H; Hsu, Chien-Ning

    2016-11-01

    Pregnancy is a critical time for fetal programming of hypertension. Nitric oxide deficiency during pregnancy causes hypertension in adult offspring. We examined whether maternal melatonin or N-acetylcysteine therapy can prevent N G -nitro-L-arginine-methyl ester-induced fetal programming of hypertension in adult offspring. Next, we aimed to identify potential gatekeeper pathways that contribute to N G -nitro-L-arginine-methyl ester -induced programmed hypertension using the next generation RNA sequencing technology. Pregnant Sprague-Dawley rats were assigned to 4 groups: control, N G -nitro-L-arginine-methyl ester, N G -nitro-L-arginine-methyl ester +melatonin, and N G -nitro-L-arginine-methyl ester+N-acetylcysteine. Pregnant rats received N G -nitro-L-arginine-methyl ester administration at 60 mg/kg/d subcutaneously during pregnancy alone, with additional 0.01% melatonin in drinking water, or with additional 1% N-acetylcysteine in drinking water during the entire pregnancy and lactation. Male offspring (n=8/group) were killed at 12 weeks of age. N G -nitro-L-arginine-methyl ester exposure during pregnancy induced programmed hypertension in adult male offspring, which was prevented by maternal melatonin or N-acetylcysteine therapy. Protective effects of melatonin and N-acetylcysteine against N G -nitro-L-arginine-methyl ester-induced programmed hypertension were associated with an increase in hydrogen sulfide-generating enzymes and hydrogen sulfide synthesis in the kidneys. Nitric oxide inhibition by N G -nitro-L-arginine-methyl ester in pregnancy caused >2000 renal transcripts to be modified during nephrogenesis stage in 1-day-old offspring kidney. Among them, genes belong to the renin-angiotensin system, and arachidonic acid metabolism pathways were potentially involved in the N G -nitro-L-arginine-methyl ester-induced programmed hypertension. However, melatonin and N-acetylcysteine reprogrammed the renin-angiotensin system and arachidonic acid pathway

  14. Oral L-Arginine Stimulates GLP-1 Secretion to Improve Glucose Tolerance in Male Mice

    DEFF Research Database (Denmark)

    Clemmensen, Christoffer; Smajilovic, Sanela; Smith, Eric P

    2013-01-01

    Pharmacological and surgical interventions that increase glucagon-like peptide 1 (GLP-1) action are effective to improve glucose homeostasis in type 2 diabetes mellitus. In light of this, nutritional strategies to enhance postprandial GLP-1 secretion, particularly in the context of diet......-induced obesity, may provide an alternative therapeutic approach. Importantly, recent evidence suggests the amino acid l-arginine, a well-known insulin secretagogue, can also stimulate release of GLP-1 from isolated rat intestine. Here we tested the hypothesis that oral l-arginine acts as a GLP-1 secretagogue...... in vivo, to augment postprandial insulin secretion and improve glucose tolerance. To test this, we administered l-arginine or vehicle by oral gavage, immediately prior to an oral glucose tolerance test in lean and diet-induced obese mice. In both lean and obese mice oral l-arginine increased plasma GLP-1...

  15. Endothelial arginine resynthesis contributes to the maintenance of vasomotor function in male diabetic mice

    DEFF Research Database (Denmark)

    Chennupati, Ramesh; Meens, Merlijn J P M T; Marion, Vincent

    2014-01-01

    AIM: Argininosuccinate synthetase (ASS) is essential for recycling L-citrulline, the by-product of NO synthase (NOS), to the NOS substrate L-arginine. Here, we assessed whether disturbed arginine resynthesis modulates endothelium-dependent vasodilatation in normal and diabetic male mice. METHODS...... of endothelial citrulline recycling to arginine did not affect blood pressure and systemic arterial vasomotor responses in healthy mice. EDNO-mediated vasodilatation was significantly more impaired in diabetic Ass-KOTie2 than in control mice demonstrating that endothelial arginine recycling becomes a limiting...... responses were studied in isolated saphenous arteries of 12- and 34-week-old Ass-KOTie2 and control animals. At the age of 10 weeks, diabetes was induced in control and Ass-KOTie2 mice by streptozotocin injections. Vasomotor responses of diabetic animals were studied 10 weeks later. MAP was similar...

  16. Improved method and its clinical application of a radioimmunoassay of arginine vasopressin in human serum

    International Nuclear Information System (INIS)

    Wagner, H.; Maier, V.; Franz, H.W.; Ulm Univ.; Ulm Univ.

    1977-01-01

    A sensitive and specific double-antibody radioimmunoassay for measuring circulating levels of arginine vasopressin in human serum is described. It is possible to detect arginine vasopressin levels of 1 μU/ml serum without extraction procedure. Normal subjects were found to have 5.7 +- 4.4 μU/ml after a dehydration period of 12 hours. Water loading diminished arginine vasopressin concentrations while dehydration incrased it. Application of furosemide over a period of 14 days brought forth constant but not significant decreases. Subjects suffering from psychogenic polydipsia showed normal levels in spite of drinking 8-12 liters of water per day. Patients suffering from liver cirrhosis with ascites showed significantly higher arginine vasopressin levels, approaching normal values when ascites was under control. (orig.) [de

  17. Synthesis, characterization and properties of L-arginine-passivated silver nanocolloids

    International Nuclear Information System (INIS)

    Sunatkari, A. L.; Talwatkar, S. S.; Tamgadge, Y. S.; Muley, G. G.

    2016-01-01

    We investigate the effect of L-arginine-surface passivation on localised surface plasmon resonance (LSPR), size and stability of colloidal Silver Nanoparticles (AgNPs) synthesized by chemical reduction method. The surface Plasmon resonance absorption peak of AgNPs shows blue shift with the increase in L-arginine concentration. Transmission electron microscopy (TEM) analysis confirmed that the average size of AgNPs reduces from 10 nm to 6 nm as the concentration of L-Arginine increased from 1 to 5 mM. The X-ray diffraction study (XRD) confirmed the formation face-centred cubic (fcc) structured AgNPs. FT-IR studies revealed strong bonding between L-arginine functional groups and AgNPs.

  18. Synthesis, characterization and properties of L-arginine-passivated silver nanocolloids

    Energy Technology Data Exchange (ETDEWEB)

    Sunatkari, A. L., E-mail: ashok.sunatkari@rediffmail.com [Department of Physics, Siddhartha College of Arts, Science and Commerce, Fort, Mumbai-400001, India. Email: ashok.sunatkari@rediffmail.com (India); Talwatkar, S. S. [Department of Physics, N.G. Aacharya and D.K. Maratha College of Arts, Science and Commerce, Chembur, Mumbai-400071, India. Email: swarna-81@rediffmail.com (India); Tamgadge, Y. S. [Department of Physics, Mahatma Phule Arts, Commerce & S.R.C. Science College, Warud-444906, India. Email: ystamgadge@gmail.com (India); Muley, G. G., E-mail: gajananggm@yahoo.co.in [Department of Physics, Sant Gadge Baba Amravati University, Amravati-444602 India. Email: gajananggm@yahoo.co.in (India)

    2016-05-06

    We investigate the effect of L-arginine-surface passivation on localised surface plasmon resonance (LSPR), size and stability of colloidal Silver Nanoparticles (AgNPs) synthesized by chemical reduction method. The surface Plasmon resonance absorption peak of AgNPs shows blue shift with the increase in L-arginine concentration. Transmission electron microscopy (TEM) analysis confirmed that the average size of AgNPs reduces from 10 nm to 6 nm as the concentration of L-Arginine increased from 1 to 5 mM. The X-ray diffraction study (XRD) confirmed the formation face-centred cubic (fcc) structured AgNPs. FT-IR studies revealed strong bonding between L-arginine functional groups and AgNPs.

  19. Improved method and its clinical application of a radioimmunoassay of arginine vasopressin in human serum

    Energy Technology Data Exchange (ETDEWEB)

    Wagner, H; Maier, V; Franz, H W [Ulm Univ. (Germany, F.R.). Abt. Endokrinologie und Stoffwechsel; Ulm Univ. (Germany, F.R.). Zentrum fuer Innere Medizin und Kinderheilkunde; Ulm Univ. (Germany, F.R.). Sektion Nephrologie)

    1977-05-01

    A sensitive and specific double-antibody radioimmunoassay for measuring circulating levels of arginine vasopressin in human serum is described. It is possible to detect arginine vasopressin levels of 1 ..mu..U/ml serum without extraction procedure. Normal subjects were found to have 5.7 +- 4.4 ..mu..U/ml after a dehydration period of 12 hours. Water loading diminished arginine vasopressin concentrations while dehydration incrased it. Application of furosemide over a period of 14 days brought forth constant but not significant decreases. Subjects suffering from psychogenic polydipsia showed normal levels in spite of drinking 8-12 liters of water per day. Patients suffering from liver cirrhosis with ascites showed significantly higher arginine vasopressin levels, approaching normal values when ascites was under control.

  20. The effect of citrulline and arginine supplementation on lactic acidemia in MELAS syndrome☆

    Science.gov (United States)

    El-Hattab, Ayman W.; Emrick, Lisa T.; Williamson, Kaitlin C.; Craigen, William J.; Scaglia, Fernando

    2013-01-01

    Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome is a mitochondrial disorder in which nitric oxide (NO) deficiency may play a role in the pathogenesis of several complications including stroke-like episodes and lactic acidosis. Supplementing the NO precursors arginine and citrulline restores NO production in MELAS syndrome. In this study we evaluated the effect of arginine or citrulline on lactic acidemia in adults with MELAS syndrome. Plasma lactate decreased significantly after citrulline supplementation, whereas the effect of arginine supplementation did not reach statistical significance. These results support the potential therapeutic utility of arginine and citrulline in MELAS syndrome and suggest that citrulline supplementation may be more efficacious. However, therapeutic efficacy of these compounds should be further evaluated in clinical trials. PMID:25411654

  1. The effect of citrulline and arginine supplementation on lactic acidemia in MELAS syndrome.

    Science.gov (United States)

    El-Hattab, Ayman W; Emrick, Lisa T; Williamson, Kaitlin C; Craigen, William J; Scaglia, Fernando

    2013-12-01

    Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome is a mitochondrial disorder in which nitric oxide (NO) deficiency may play a role in the pathogenesis of several complications including stroke-like episodes and lactic acidosis. Supplementing the NO precursors arginine and citrulline restores NO production in MELAS syndrome. In this study we evaluated the effect of arginine or citrulline on lactic acidemia in adults with MELAS syndrome. Plasma lactate decreased significantly after citrulline supplementation, whereas the effect of arginine supplementation did not reach statistical significance. These results support the potential therapeutic utility of arginine and citrulline in MELAS syndrome and suggest that citrulline supplementation may be more efficacious. However, therapeutic efficacy of these compounds should be further evaluated in clinical trials.

  2. Detecting organic gunpowder residues from handgun use

    Science.gov (United States)

    MacCrehan, William A.; Ricketts, K. Michelle; Baltzersen, Richard A.; Rowe, Walter F.

    1999-02-01

    The gunpowder residues that remain after the use of handguns or improvised explosive devices pose a challenge for the forensic investigator. Can these residues be reliably linked to a specific gunpowder or ammunition? We investigated the possibility by recovering and measuring the composition of organic additives in smokeless powder and its post-firing residues. By determining gunpowder additives such as nitroglycerin, dinitrotoluene, ethyl- and methylcentralite, and diphenylamine, we hope to identify the type of gunpowder in the residues and perhaps to provide evidence of a match to a sample of unfired powder. The gunpowder additives were extracted using an automated technique, pressurized fluid extraction (PFE). The conditions for the quantitative extraction of the additives using neat and solvent-modified supercritical carbon dioxide were investigated. All of the major gunpowder additives can be determined with baseline resolution using capillary electrophoresis (CE) with a micellar agent and UV absorbance detection. A study of candidate internal standards for use in the CE method is also presented. The PFE/CE technique is used to evaluate a new residue sampling protocol--asking shooters to blow their noses. In addition, an initial investigation of the compositional differences among unfired and post-fired .22 handgun residues is presented.

  3. Plasma l-citrulline concentrations in l-arginine-supplemented healthy dogs.

    Science.gov (United States)

    Flynn, K M; Kellihan, H B; Trepanier, L A

    2017-08-01

    To determine whether oral l-arginine increases plasma [l-citrulline] in dogs. Eleven healthy staff-owned dogs were used in this study. Dogs (n = 3) were given l-arginine (50mg/kg PO q8h) for 7 days, and plasma [l-arginine] and [l-citrulline] were analyzed by high performance liquid chromatography at baseline (BL), steady state trough, and 0.5, 1, 1.5, 2, 4, 6, and 8 h after final dosing on day 7. Eleven dogs were then treated with 100mg/kg l-arginine PO q8h for 7 days, and [l-arginine] and [l-citrulline] were measured at BL, steady state trough, and at peak 4 hrs after dosing (T4 hrs). - Plasma [l-arginine] and [l-citrulline] peaked at T4 hrs on the 50mg/kg dosage. Target outcome, modeled after human study results, of a doubling of [l-arginine] and a 25-30% increase in [l-citrulline] from BL were not reached. After the 100mg/kg dosage, plasma [l-arginine] increased from a BL median of 160.1 μM (range, 100.2-231.4 μM) to a peak of 417.4 μM (206.5-807.3 μM) at T4 hrs, and plasma [l-citrulline] increased from a BL median of 87.8 μM (59.1-117.1 μM) to peak of 102.2 μM (47.4-192.6 μM) at T4 hrs. Ten of eleven dogs showed a doubling of plasma [l-arginine] and 4/11 dogs achieved 25-30% or greater increases in plasma [l-citrulline]. No adverse effects on heart rate or blood pressure were noted. - Oral l-arginine dosage of 100mg/kg q8h doubles plasma [l-arginine] in healthy dogs, but conversion to l-citrulline is quite variable. Further evaluation of this dosage regimen in dogs with pulmonary hypertension is warranted. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Arginine metabolism by macrophages promotes cardiac and muscle fibrosis in mdx muscular dystrophy.

    Directory of Open Access Journals (Sweden)

    Michelle Wehling-Henricks

    2010-05-01

    Full Text Available Duchenne muscular dystrophy (DMD is the most common, lethal disease of childhood. One of 3500 new-born males suffers from this universally-lethal disease. Other than the use of corticosteroids, little is available to affect the relentless progress of the disease, leading many families to use dietary supplements in hopes of reducing the progression or severity of muscle wasting. Arginine is commonly used as a dietary supplement and its use has been reported to have beneficial effects following short-term administration to mdx mice, a genetic model of DMD. However, the long-term effects of arginine supplementation are unknown. This lack of knowledge about the long-term effects of increased arginine metabolism is important because elevated arginine metabolism can increase tissue fibrosis, and increased fibrosis of skeletal muscles and the heart is an important and potentially life-threatening feature of DMD.We use both genetic and nutritional manipulations to test whether changes in arginase metabolism promote fibrosis and increase pathology in mdx mice. Our findings show that fibrotic lesions in mdx muscle are enriched with arginase-2-expressing macrophages and that muscle macrophages stimulated with cytokines that activate the M2 phenotype show elevated arginase activity and expression. We generated a line of arginase-2-null mutant mdx mice and found that the mutation reduced fibrosis in muscles of 18-month-old mdx mice, and reduced kyphosis that is attributable to muscle fibrosis. We also observed that dietary supplementation with arginine for 17-months increased mdx muscle fibrosis. In contrast, arginine-2 mutation did not reduce cardiac fibrosis or affect cardiac function assessed by echocardiography, although 17-months of dietary supplementation with arginine increased cardiac fibrosis. Long-term arginine treatments did not decrease matrix metalloproteinase-2 or -9 or increase the expression of utrophin, which have been reported as beneficial

  5. Protein Arginine Methyltransferase 5 Inhibition Upregulates Foxp3+ Regulatory T Cells Frequency and Function during the Ulcerative Colitis

    Directory of Open Access Journals (Sweden)

    Yingxia Zheng

    2017-05-01

    Full Text Available Ulcerative colitis (UC pathogenesis is related to imbalance of immune responses, and the equilibrium between inflammatory T cells and Foxp3+ regulatory T cells (Tregs plays an important role in the intestinal homeostasis. Protein arginine methyltransferases (PRMTs regulate chromatin remodeling and gene expression. Here, we investigated whether inhibition of PRMTs affects colitis pathogenesis in mice and inflammatory bowel disease patients and further explored the underlying mechanisms. In this study, we found that protein arginine N-methyltransferase inhibitor 1 (AMI-1 treatments increased Tregs frequency, function, and reduced colitis incidence. Adoptive transfer of AMI-1-treated Tregs could reduce the colitis incidence. Colitis was associated with increased local PRMT5 expression, which was inhibited by AMI-1 treatment. Additionally, PRMT5 knockdown T cells produced a better response to TGFβ and promoted Tregs differentiation through decreased DNA methyltransferase 1 (DNMT1 expression. PRMT5 also enhanced H3K27me3 and DNMT1 binding to Foxp3 promoter, which restricted Tregs differentiation. Furthermore, PRMT5 knockdown led to decreased Foxp3 promoter methylation during Tregs induction. PRMT5 expression had a negative relationship with Tregs in UC patients, knockdown of PRMT5 expression increased Tregs frequency and decreased TNFα, IL-6, and IL-13 levels. Our study outlines a novel regulation of PRMT5 on Tregs development and function. Strategies to decrease PRMT5 expression might have therapeutic potential to control UC.

  6. L-ARGININE PREVENTS METABOLIC EFFECTS OF HIGH GLUCOSE IN DIABETIC MICE

    OpenAIRE

    West, Matthew B.; Ramana, Kota V.; Kaiserova, Karin; Srivastava, Satish K.; Bhatnagar, Aruni

    2008-01-01

    We tested the hypothesis that activation of the polyol pathway and protein kinase C (PKC) during diabetes is due to loss of NO. Our results show that after 4 weeks of streptozotocin-induced diabetes, treatment with L-arginine restored NO levels and prevented tissue accumulation of sorbitol in mice, which was accompanied by an increase in glutathiolation of aldose reductase. L-arginine treatment decreased superoxide generation in the aorta, total PKC activity and PKC-βII phosphorylation in the...

  7. Kidney Mass Reduction Leads to l-Arginine Metabolism-Dependent Blood Pressure Increase in Mice.

    Science.gov (United States)

    Pillai, Samyuktha Muralidharan; Seebeck, Petra; Fingerhut, Ralph; Huang, Ji; Ming, Xiu-Fen; Yang, Zhihong; Verrey, François

    2018-02-25

    Uninephrectomy (UNX) is performed for various reasons, including kidney cancer or donation. Kidneys being the main site of l-arginine production in the body, we tested whether UNX mediated kidney mass reduction impacts l-arginine metabolism and thereby nitric oxide production and blood pressure regulation in mice. In a first series of experiments, we observed a significant increase in arterial blood pressure 8 days post-UNX in female and not in male mice. Further experimental series were performed in female mice, and the blood pressure increase was confirmed by telemetry. l-citrulline, that is used in the kidney to produce l-arginine, was elevated post-UNX as was also asymmetric dimethylarginine, an inhibitor of nitric oxide synthase that competes with l-arginine and is a marker for renal failure. Interestingly, the UNX-induced blood pressure increase was prevented by supplementation of the diet with 5% of the l-arginine precursor, l-citrulline. Because l-arginine is metabolized in the kidney and other peripheral tissues by arginase-2, we tested whether the lack of this metabolic pathway also compensates for decreased l-arginine production in the kidney and/or for local nitric oxide synthase inhibition and consecutive blood pressure increase. Indeed, upon uninephrectomy, arginase-2 knockout mice (Arg-2 -/- ) neither displayed an increase in asymmetric dimethylarginine and l-citrulline plasma levels nor a significant increase in blood pressure. UNX leads to a small increase in blood pressure that is prevented by l-citrulline supplementation or arginase deficiency, 2 measures that appear to compensate for the impact of kidney mass reduction on l-arginine metabolism. © 2018 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

  8. Residual gas analysis

    International Nuclear Information System (INIS)

    Berecz, I.

    1982-01-01

    Determination of the residual gas composition in vacuum systems by a special mass spectrometric method was presented. The quadrupole mass spectrometer (QMS) and its application in thin film technology was discussed. Results, partial pressure versus time curves as well as the line spectra of the residual gases in case of the vaporization of a Ti-Pd-Au alloy were demonstrated together with the possible construction schemes of QMS residual gas analysers. (Sz.J.)

  9. Análise experimental de blocos intertravados de concreto com adição de resíduos do processo de recauchutagem de pneus = Analysis of experimental interlocking blocks of concrete with addition of residues of process the tires retreading production

    Directory of Open Access Journals (Sweden)

    Cesar Fabiano Fioriti

    2010-07-01

    Full Text Available Com o aumento da população nos últimos anos, a indústria de modo geral tem se adequado à demanda resultante. A indústria do processo de recauchutagem de pneus gera resíduos que em sua maioria têm sido descartados sem nenhum controle. Este fato contribui para aumentar a poluição ambiental e favorecer a proliferação de vetores nocivos àsaúde. Visando encontrar uma aplicação para esse tipo de resíduo, neste trabalho serão apresentados resultados experimentais de blocos intertravados para pavimentos de concreto, com traços adicionados de resíduos de pneus. Foram confeccionados blocos intertravados em que se determinou, por meio de ensaios laboratoriais, a necessidade de se fixar o traço que desse maior retorno quanto às características analisadas. Verificaram-se quatro tipos de traços de concreto com resíduos de pneus. Procedeu-se aos ensaios de resistência mecânicaà compressão, absorção de água e resistência ao impacto. Pelos resultados preliminares obtidos, verificou-se que são satisfatórios, confirmando-se a possibilidade de aplicação desse tipo de bloco intertravado em ambientes com solicitações baixas, o que traria, além da economia das fontes naturais de agregados, benefícios ecológicos pela reutilização dos resíduos da recauchutagem de pneus.With the population growth in recent years, industry in general has ajusted itself to resulting demand. the industry of tire retreading generates residues that have been discarded without any control. this adds to environmental pollution and promotes the proliferation of vectors harmful to health. aiming to find an application for this type of residues, this study presents experimental results to interlocking concrete block pavements, with addition of residuestires. interlocking blocks were built up and we determined, through laboratory tests, the need to set the mark that provide greater return regarding analyzed characteristics. there are four types of dosage

  10. tlpA gene expression is required for arginine and bicarbonate chemotaxis in Helicobacter pylori.

    Science.gov (United States)

    Cerda, Oscar A; Núñez-Villena, Felipe; Soto, Sarita E; Ugalde, José Manuel; López-Solís, Remigio; Toledo, Héctor

    2011-01-01

    About half of the human population is infected with Helicobacter pylori, a bacterium causing gastritis, peptic ulcer and progression to gastric cancer. Chemotaxis and flagellar motility are required for colonization and persistence of H. pylori in the gastric mucus layer. It is not completely clear which chemical gradients are used by H. pylori to maintain its position. TlpA, a chemotaxis receptor for arginine/ bicarbonate, has been identified. This study aimed to find out whether tlpA gene expression is required for the chemotactic response to arginine/bicarbonate. Wild-type motile H. pylori ATCC 700392 and H. pylori ATCC 43504, a strain having an interrupted tlpA gene, were used. Also, a tlpA-knockout mutant of H. pylori 700392 (H. pylori 700-tlpA::cat) was produced by homologous recombination. Expression of tlpA was assessed by a Reverse Transcriptase-Polymerase Chain Reaction (RT-PCR) assay. Chemotaxis was measured as a Relative Chemotaxis Response (RCR) by a modified capillary assay. H. pylori 700392 presented chemotaxis to arginine and sodium bicarbonate. H. pylori 700-tlpA::cat showed neither tlpA gene expression nor chemotaxis towards arginine and bicarbonate. Besides confirming that TlpA is a chemotactic receptor for arginine/bicarbonate in H. pylori, this study showed that tlpA gene expression is required for arginine/bicarbonate chemotaxis.

  11. The role of arginine metabolic pathway during embryogenesis and germination in maritime pine (Pinus pinaster Ait.).

    Science.gov (United States)

    Llebrés, María-Teresa; Pascual, María-Belén; Debille, Sandrine; Trontin, Jean-François; Harvengt, Luc; Avila, Concepción; Cánovas, Francisco M

    2018-03-01

    Vegetative propagation through somatic embryogenesis is critical in conifer biotechnology towards multivarietal forestry that uses elite varieties to cope with environmental and socio-economic issues. An important and still sub-optimal process during in vitro maturation of somatic embryos (SE) is the biosynthesis and deposition of storage proteins, which are rich in amino acids with high nitrogen (N) content, such as arginine. Mobilization of these N-rich proteins is essential for the germination and production of vigorous somatic seedlings. Somatic embryos accumulate lower levels of N reserves than zygotic embryos (ZE) at a similar stage of development. To understand the molecular basis for this difference, the arginine metabolic pathway has been characterized in maritime pine (Pinus pinaster Ait.). The genes involved in arginine metabolism have been identified and GFP-fusion constructs were used to locate the enzymes in different cellular compartments and clarify their metabolic roles during embryogenesis and germination. Analysis of gene expression during somatic embryo maturation revealed high levels of transcripts for genes involved in the biosynthesis and metabolic utilization of arginine. By contrast, enhanced expression levels were only observed during the last stages of maturation and germination of ZE, consistent with the adequate accumulation and mobilization of protein reserves. These results suggest that arginine metabolism is unbalanced in SE (simultaneous biosynthesis and degradation of arginine) and could explain the lower accumulation of storage proteins observed during the late stages of somatic embryogenesis.

  12. tlpA gene expression is required for arginine and bicarbonate chemotaxis in Helicobacter pylori

    Directory of Open Access Journals (Sweden)

    Oscar A Cerda

    2011-01-01

    Full Text Available About half of the human population is infected with Helicobacter pylori, a bacterium causing gastritis, peptic ulcer and progression to gastric cancer. Chemotaxis and flagellar motility are required for colonization and persistence of H. pylori in the gastric mucus layer. It is not completely clear which chemical gradients are used by H. pylori to maintain its position. TlpA, a chemotaxis receptor for arginine/ bicarbonate, has been identified. This study aimed to find out whether tlpA gene expression is required for the chemotactic response to arginine/bicarbonate. Wild-type motile H. pylori ATCC 700392 and H. pylori ATCC 43504, a strain having an interrupted tlpA gene, were used. Also, a tlpA-knockout mutant of H. pylori 700392 (H. pylori 700-tlpA::cat was produced by homologous recombination. Expression of tlpA was assessed by a Reverse Transcriptase-Polymerase Chain Reaction (RT-PCR assay. Chemotaxis was measured as a Relative Chemotaxis Response (RCR by a modified capillary assay. H. pylori 700392 presented chemotaxis to arginine and sodium bicarbonate. H. pylori 700-tlpA::cat showed neither tlpA gene expression nor chemotaxis towards arginine and bicarbonate. Besides confirming that TlpA is a chemotactic receptor for arginine/bicarbonate in H. pylori, this study showed that tlpA gene expression is required for arginine/bicarbonate chemotaxis.

  13. Effects of arginine vasopressin on musical working memory.

    Science.gov (United States)

    Granot, Roni Y; Uzefovsky, Florina; Bogopolsky, Helena; Ebstein, Richard P

    2013-01-01

    Previous genetic studies showed an association between variations in the gene coding for the 1a receptor of the neuro-hormone arginine vasopressin (AVP) and musical working memory (WM). The current study set out to test the influence of intranasal administration (INA) of AVP on musical as compared to verbal WM using a double blind crossover (AVP-placebo) design. Two groups of 25 males were exposed to 20 IU of AVP in one session, and 20 IU of saline water (placebo) in a second session, 1 week apart. In each session subjects completed the tonal subtest from Gordon's "Musical Aptitude Profile," the interval subtest from the "Montreal Battery for Evaluation of Amusias (MBEA)," and the forward and backward digit span tests. Scores in the digit span tests were not influenced by AVP. In contrast, in the music tests there was an AVP effect. In the MBEA test, scores for the group receiving placebo in the first session (PV) were higher than for the group receiving vasopressin in the first session (VP) (p music test these scores were significantly correlated with memory scores. Together the results reflect a complex interaction between AVP, musical memory, arousal, and contextual effects such as session, and base levels of memory. The results are interpreted in light of music's universal use as a means to modulate arousal on the one hand, and AVP's influence on mood, arousal, and social interactions on the other.

  14. An application of residual current protective device at electrical installation

    International Nuclear Information System (INIS)

    Firman Silitonga

    2008-01-01

    In an electrical installation, a protection for overload and short circuit are always to be installed. In addition to the installation, it is necessary to be installed a protection device for residual current because both the short circuit and the overload device protection will not work for the residual current. The quantity of the residual current must be defined first at any electrical installation to define an appropriate residual current protection so that not every residual current will break the circuit down. This paper will explain a method how to install a residual protection device for 3500 VA or more at TN and TT of earthing system. (author)

  15. The arginine methyltransferase Rmt2 is enriched in the nucleus and co-purifies with the nuclear porins Nup49, Nup57 and Nup100

    International Nuclear Information System (INIS)

    Olsson, Ida; Berrez, Jean-Marc; Leipus, Arunas; Ostlund, Cecilia; Mutvei, Ann

    2007-01-01

    Arginine methylation is a post-translational modification of proteins implicated in RNA processing, protein compartmentalization, signal transduction, transcriptional regulation and DNA repair. In a screen for proteins associated with the nuclear envelope in the yeast Saccharomyces cerevisiae, we have identified the arginine methyltransferase Rmt2, previously shown to methylate the ribosomal protein L12. By indirect immunofluorescence and subcellular fractionations we demonstrate here that Rmt2 has nuclear and cytoplasmic localizations. Biochemical analysis of a fraction enriched in nuclei reveals that nuclear Rmt2 is resistant to extractions with salt and detergent, indicating an association with structural components. This was supported by affinity purification experiments with TAP-tagged Rmt2. Rmt2 was found to co-purify with the nucleoporins Nup49, Nup57 and Nup100, revealing a novel link between arginine methyltransferases and the nuclear pore complex. In addition, a genome-wide transcription study of the rmt2Δ mutant shows significant downregulation of the transcription of MYO1, encoding the Type II myosin heavy chain required for cytokinesis and cell separation

  16. The protective effect of NG-nitro-L-arginine methyl ester and insulin on nitric oxide inhibition and pathology in experimental diabetic rat liver

    International Nuclear Information System (INIS)

    Ozden, H.; Guven, G.; Tekin, N.; Akyuz, F.; Gurer, F.; Kucuk, F.; Ustuner, Mehmet C.; Yaylak, F.

    2009-01-01

    Objective was to determine on protective role of NG-nitro-L-arginine methyl ester (L-NAME) and insulin on the liver in streptoozotocin (STZ) induced diabetic rats. This study was performed in the Department of Biochemistry, Faculty of Medicine, Eskisehir Osmangazi University, Eskisehir, Turkey in 2007. Forty male Wistar albino rats were divided into 5 groups. These were untreated, diabetic control, STZ+insulin, STZ+L-NAME and STZ+insulin+L-NAME induced groups. The STZ was intraperitonally injected into 3 groups and includes insulin, L-NAME and their joint administrations as protective agents. The blood glucose and nitric oxide (NO) levels were determined. The tissue samples were obtained at the end of the fourth week. The liver tissue distortions were evaluated using hematoxylin and eosin staining. The serum glucose level was significantly higher in diabetic control (p=0.000), than the untreated group. The focal pseudo lobular structures without vena centralis increased portal fibrillary necrosis and bile duct stenosis with voagulation necrosis of the peripheral hepatocytes were more observed in diabetic group than the protective agent groups. In addition, insulin and L-NAME lead to hepatocyte regeneration and minimal mononuclear cell infiltration was noted. NG-nitro-L-arginine methyl ester inhibits NO level in STZ+L-NAME induced group. NG-nitro-L-arginine methyl ester either alone or with insulin combination significantly attenuates the liver morphological disarrangements in STZ induced diabetic rats. (author)

  17. Harvesting and handling agricultural residues for energy

    Energy Technology Data Exchange (ETDEWEB)

    Jenkins, B.M.; Summer, H.R.

    1986-05-01

    Significant progress in understanding the needs for design of agricultural residue collection and handling systems has been made but additional research is required. Recommendations are made for research to (a) integrate residue collection and handling systems into general agricultural practices through the development of multi-use equipment and total harvest systems; (b) improve methods for routine evaluation of agricultural residue resources, possibly through remote sensing and image processing; (c) analyze biomass properties to obtain detailed data relevant to engineering design and analysis; (d) evaluate long-term environmental, social, and agronomic impacts of residue collection; (e) develop improved equipment with higher capacities to reduce residue collection and handling costs, with emphasis on optimal design of complete systems including collection, transportation, processing, storage, and utilization; and (f) produce standard forms of biomass fuels or products to enhance material handling and expand biomass markets through improved reliability and automatic control of biomass conversion and other utilization systems. 118 references.

  18. L-arginine and Arginase Products Potentiate Dexmedetomidine-induced Contractions in the Rat Aorta.

    Science.gov (United States)

    Wong, Emily S W; Man, Ricky Y K; Ng, Kwok F J; Leung, Susan W S; Vanhoutte, Paul M

    2018-03-01

    The α2-adrenergic sedative/anesthetic agent dexmedetomidine exerts biphasic effects on isolated arteries, causing endothelium-dependent relaxations at concentrations at or below 30 nM, followed by contractions at higher concentrations. L-arginine is a common substrate of endothelial nitric oxide synthase and arginases. This study was designed to investigate the role of L-arginine in modulating the overall vascular response to dexmedetomidine. Isometric tension was measured in isolated aortic rings of Sprague Dawley rats. Cumulative concentrations of dexmedetomidine (10 nM to 10 μM) were added to quiescent rings (with and without endothelium) after previous incubation with vehicle, N-nitro-L-arginine methyl ester hydrochloride (L-NAME; nitric oxide synthase inhibitor), prazosin (α1-adrenergic antagonist), rauwolscine (α2-adrenergic antagonist), L-arginine, (S)-(2-boronethyl)-L-cysteine hydrochloride (arginase inhibitor), N-hydroxy-L-arginine (arginase inhibitor), urea and/or ornithine. In some preparations, immunofluorescent staining, immunoblotting, or measurement of urea content were performed. Dexmedetomidine did not contract control rings with endothelium but evoked concentration-dependent increases in tension in such rings treated with L-NAME (Emax 50 ± 4%) or after endothelium-removal (Emax 74 ± 5%; N = 7 to 12). Exogenous L-arginine augmented the dexmedetomidine-induced contractions in the presence of L-NAME (Emax 75 ± 3%). This potentiation was abolished by (S)-(2-boronethyl)-L-cysteine hydrochloride (Emax 16 ± 4%) and N-hydroxy-L-arginine (Emax 18 ± 4%). Either urea or ornithine, the downstream arginase products, had a similar potentiating effect as L-arginine. Immunoassay measurements demonstrated an upregulation of arginase I by L-arginine treatment in the presence of L-NAME (N = 4). These results suggest that when vascular nitric oxide homeostasis is impaired, the potentiation of the vasoconstrictor effect of

  19. Role of distal arginine in early sensing intermediates in the heme domain of the oxygen sensor FixL.

    Science.gov (United States)

    Jasaitis, Audrius; Hola, Klara; Bouzhir-Sima, Latifa; Lambry, Jean-Christophe; Balland, Veronique; Vos, Marten H; Liebl, Ursula

    2006-05-16

    FixL is a bacterial heme-based oxygen sensor, in which release of oxygen from the sensing PAS domain leads to activation of an associated kinase domain. Static structural studies have suggested an important role of the conserved residue arginine 220 in signal transmission at the level of the heme domain. To assess the role of this residue in the dynamics and properties of the initial intermediates in ligand release, we have investigated the effects of R220X (X = I, Q, E, H, or A) mutations in the FixLH heme domain on the dynamics and spectral properties of the heme upon photolysis of O(2), NO, and CO using femtosecond transient absorption spectroscopy. Comparison of transient spectra for CO and NO dissociation with steady-state spectra indicated less strain on the heme in the ligand dissociation species for all mutants compared to the wild type (WT). For CO and NO, the kinetics were similar to those of the wild type, with the exception of (1) a relatively low yield of picosecond NO rebinding to R220A, presumably related to the increase in the free volume of the heme pocket, and (2) substantial pH-dependent picosecond to nanosecond rebinding of CO to R220H, related to formation of a hydrogen bond between CO and histidine 220. Upon excitation of the complex bound with the physiological sensor ligand O(2), a 5-8 ps decay phase and a nondecaying (>4 ns) phase were observed for WT and all mutants. The strong distortion of the spectrum associated with the decay phase in WT is substantially diminished in all mutant proteins, indicating an R220-induced role of the heme in the primary intermediate in signal transmission. Furthermore, the yield of dissociated oxygen after this phase ( approximately 10% in WT) is increased in all mutants, up to almost unity in R220A, indicating a key role of R220 in caging the oxygen near the heme through hydrogen bonding. Molecular dynamics simulations corroborate these findings and suggest motions of O(2) and arginine 220 away from the heme

  20. Identification and characterization of new molecular partners for the protein arginine methyltransferase 6 (PRMT6.

    Directory of Open Access Journals (Sweden)

    Alessandra Lo Sardo

    Full Text Available PRMT6 is a protein arginine methyltransferase that has been implicated in transcriptional regulation, DNA repair, and human immunodeficiency virus pathogenesis. Only few substrates of this enzyme are known and therefore its cellular role is not well understood. To identify in an unbiased manner substrates and potential regulators of PRMT6 we have used a yeast two-hybrid approach. We identified 36 new putative partners for PRMT6 and we validated the interaction in vivo for 7 of them. In addition, using invitro methylation assay we identified 4 new substrates for PRMT6, extending the involvement of this enzyme to other cellular processes beyond its well-established role in gene expression regulation. Holistic approaches create molecular connections that allow to test functional hypotheses. The assembly of PRMT6 protein network allowed us to formulate functional hypotheses which led to the discovery of new molecular partners for the architectural transcription factor HMGA1a, a known substrate for PRMT6, and to provide evidences for a modulatory role of HMGA1a on the methyltransferase activity of PRMT6.

  1. The uptake of arginine-rich cell-penetrating peptides: putting the puzzle together.

    Science.gov (United States)

    Brock, Roland

    2014-05-21

    Over the past 20 years, cell-penetrating peptides (CPPs) have captured the attention of biomedical researchers, biophysicists, and (bio)organic chemists. These molecules efficiently enter cells and mediate entry of (macro)molecules that by themselves do not cross the plasma membrane. Since their discovery, models on the mechanism by which uptake occurs have seen major revisions. Starting from direct penetration across the plasma membrane, it later became apparent that for large molecular weight cargos in particular, endocytosis plays a role in uptake and furthermore that the route of uptake is a function of CPP, cell-type, cargo, and concentration. For the class of arginine-rich CPPs, this dependence on conditions has been elucidated in particular. As I will discuss here for this class of CPPs, a downside of this multitude of possibilities has been a lack of attention for commonalities in the observation of apparently distinct phenomena. At the same time, differences of apparently similar observations were not appreciated sufficiently. In addition, there has been insufficient acknowledgment of observations that are incompatible with the proposed models. Nevertheless, a considerable amount of data can be assembled into a quite coherent picture and the data that is left creates the basis for concrete future lines of research to resolve the questions that remain. Moreover, any uptake mechanism has its distinct structure-activity relationship for uptake giving room for the molecular design of molecules to preferentially direct uptake to either of them.

  2. Simultaneous silencing of two arginine decarboxylase genes alters development in Arabidopsis

    Directory of Open Access Journals (Sweden)

    Diana eSánchez-Rangel

    2016-03-01

    Full Text Available Polyamines (PAs are small aliphatic polycations that are found ubiquitously in all organisms. In plants, PAs are involved in diverse biological processes such as growth, development, and stress responses. In Arabidopsis thaliana, the arginine decarboxylase enzymes (ADC1 and 2 catalyze the first step of PA biosynthesis. For a better understanding of PA biological functions, mutants in PA biosynthesis have been generated; however, the double adc1/adc2 mutant is not viable in A. thaliana. In this study, we generated non-lethal A. thaliana lines through an artificial microRNA that simultaneously silenced the two ADC genes (amiR:ADC. The generated transgenic lines (amiR:ADC-L1 and -L2 showed reduced AtADC1 and AtADC2 transcript levels. For further analyses the amiR:ADC-L2 line was selected. We found that the amiR:ADC-L2 line showed a significant decrease of their PA levels. The co-silencing revealed a stunted growth in A. thaliana seedlings, plantlets and delay in its flowering rate; these phenotypes were reverted with PA treatment. In addition, amiR:ADC-L2 plants displayed two seed phenotypes, such as yellow and brownish seeds. The yellow mutant seeds were smaller than adc1, adc2 mutants and wild type seeds; however, the brownish were the smallest seeds with arrested embryos at the torpedo stage. These data reinforce the importance of PA homeostasis in the plant development processes.

  3. Deregulation of the arginine deiminase (arc) operon in penicillin-tolerant mutants of Streptococcus gordonii.

    Science.gov (United States)

    Caldelari, I; Loeliger, B; Langen, H; Glauser, M P; Moreillon, P

    2000-10-01

    Penicillin tolerance is an incompletely understood phenomenon that allows bacteria to resist drug-induced killing. Tolerance was studied with independent Streptococcus gordonii mutants generated by cyclic exposure to 500 times the MIC of penicillin. Parent cultures lost 4 to 5 log(10) CFU/ml of viable counts/24 h. In contrast, each of four independent mutant cultures lost bacteria and were encoded by an operon that was >80% similar to the arginine-deiminase (arc) operon of these organisms. Partial nucleotide sequencing and insertion inactivation of the S. gordonii arc locus indicated that tolerance was not a direct consequence of arc alteration. On the other hand, genetic transformation of tolerance by Tol1 DNA always conferred arc deregulation. In nontolerant recipients, arc was repressed during exponential growth and up-regulated during postexponential growth. In tolerant transformants, arc was constitutively expressed. Tol1 DNA transformed tolerance at the same rate as transformation of a point mutation (10(-2) to 10(-3)). The tolerance mutation mapped on a specific chromosomal fragment but was physically distant from arc. Importantly, arc deregulation was observed in most (6 of 10) of additional independent penicillin-tolerant mutants. Thus, although not exclusive, the association between arc deregulation and tolerance was not fortuitous. Since penicillin selection mimicked the antibiotic pressure operating in the clinical environment, arc deregulation might be an important correlate of naturally occurring tolerance and help in understanding the mechanism(s) underlying this clinically problematic phenotype.

  4. Growth and dielectric, mechanical, thermal and etching studies of an organic nonlinear optical L-arginine trifluoroacetate (LATF) single crystal

    International Nuclear Information System (INIS)

    Arjunan, S.; Mohan Kumar, R.; Mohan, R.; Jayavel, R.

    2008-01-01

    L-arginine trifluoroacetate, an organic nonlinear optical material, has been synthesized from aqueous solution. Bulk single crystal of dimension 57 mm x 5 mm x 3 mm has been grown by temperature lowering technique. Powder X-ray diffraction studies confirmed the monoclinic structure of the grown L-arginine trifluoroacetate crystal. Linear optical property of the grown crystal has been studied by UV-vis spectrum. Dielectric response of the L-arginine trifluoroacetate crystal was analysed for different frequencies and temperatures in detail. Microhardness study on the sample reveals that the crystal possesses relatively higher hardness compared to many organic crystals. Thermal analyses confirmed that the L-arginine trifluoroacetate material is thermally stable upto 212 deg. C. The etching studies have been performed to assess the perfection of the L-arginine trifluoroacetate crystal. Kurtz powder second harmonic generation test confirms the nonlinear optical properties of the as-grown L-arginine trifluoroacetate crystal

  5. Intracellular L-arginine concentration does not determine NO production in endothelial cells: Implications on the 'L-arginine paradox'

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Soyoung; Mohan, Srinidi [Department of Pharmaceutical Sciences, University at Buffalo, The State University of New York, Buffalo, NY 14260 (United States); Fung, Ho-Leung, E-mail: hlfung@buffalo.edu [Department of Pharmaceutical Sciences, University at Buffalo, The State University of New York, Buffalo, NY 14260 (United States)

    2011-11-04

    Highlights: Black-Right-Pointing-Pointer Our findings provide a possible solution to the 'L-arginine paradox'. Black-Right-Pointing-Pointer Extracellular L-arginine concentration is the major determinant of NO production. Black-Right-Pointing-Pointer Cellular L-arginine action is limited by cellular ARG transport, not the K{sub m} of NOS. Black-Right-Pointing-Pointer We explain how L-arginine supplementation can work to increase endothelial function. -- Abstract: We examined the relative contributory roles of extracellular vs. intracellular L-arginine (ARG) toward cellular activation of endothelial nitric oxide synthase (eNOS) in human endothelial cells. EA.hy926 human endothelial cells were incubated with different concentrations of {sup 15}N{sub 4}-ARG, ARG, or L-arginine ethyl ester (ARG-EE) for 2 h. To modulate ARG transport, siRNA for ARG transporter (CAT-1) vs. sham siRNA were transfected into cells. ARG transport activity was assessed by cellular fluxes of ARG, {sup 15}N{sub 4}-ARG, dimethylarginines, and L-citrulline by an LC-MS/MS assay. eNOS activity was determined by nitrite/nitrate accumulation, either via a fluorometric assay or by{sup 15}N-nitrite or estimated {sup 15}N{sub 3}-citrulline concentrations when {sup 15}N{sub 4}-ARG was used to challenge the cells. We found that ARG-EE incubation increased cellular ARG concentration but no increase in nitrite/nitrate was observed, while ARG incubation increased both cellular ARG concentration and nitrite accumulation. Cellular nitrite/nitrate production did not correlate with cellular total ARG concentration. Reduced {sup 15}N{sub 4}-ARG cellular uptake in CAT-1 siRNA transfected cells vs. control was accompanied by reduced eNOS activity, as determined by {sup 15}N-nitrite, total nitrite and {sup 15}N{sub 3}-citrulline formation. Our data suggest that extracellular ARG, not intracellular ARG, is the major determinant of NO production in endothelial cells. It is likely that once transported inside

  6. Intracellular L-arginine concentration does not determine NO production in endothelial cells: Implications on the “L-arginine paradox”

    International Nuclear Information System (INIS)

    Shin, Soyoung; Mohan, Srinidi; Fung, Ho-Leung

    2011-01-01

    Highlights: ► Our findings provide a possible solution to the “L-arginine paradox”. ► Extracellular L-arginine concentration is the major determinant of NO production. ► Cellular L-arginine action is limited by cellular ARG transport, not the K m of NOS. ► We explain how L-arginine supplementation can work to increase endothelial function. -- Abstract: We examined the relative contributory roles of extracellular vs. intracellular L-arginine (ARG) toward cellular activation of endothelial nitric oxide synthase (eNOS) in human endothelial cells. EA.hy926 human endothelial cells were incubated with different concentrations of 15 N 4 -ARG, ARG, or L-arginine ethyl ester (ARG-EE) for 2 h. To modulate ARG transport, siRNA for ARG transporter (CAT-1) vs. sham siRNA were transfected into cells. ARG transport activity was assessed by cellular fluxes of ARG, 15 N 4 -ARG, dimethylarginines, and L-citrulline by an LC–MS/MS assay. eNOS activity was determined by nitrite/nitrate accumulation, either via a fluorometric assay or by 15 N-nitrite or estimated 15 N 3 -citrulline concentrations when 15 N 4 -ARG was used to challenge the cells. We found that ARG-EE incubation increased cellular ARG concentration but no increase in nitrite/nitrate was observed, while ARG incubation increased both cellular ARG concentration and nitrite accumulation. Cellular nitrite/nitrate production did not correlate with cellular total ARG concentration. Reduced 15 N 4 -ARG cellular uptake in CAT-1 siRNA transfected cells vs. control was accompanied by reduced eNOS activity, as determined by 15 N-nitrite, total nitrite and 15 N 3 -citrulline formation. Our data suggest that extracellular ARG, not intracellular ARG, is the major determinant of NO production in endothelial cells. It is likely that once transported inside the cell, ARG can no longer gain access to the membrane-bound eNOS. These observations indicate that the “L-arginine paradox” should not consider intracellular ARG

  7. A role for PPARα in the regulation of arginine metabolism and nitric oxide synthesis.

    Science.gov (United States)

    Guelzim, Najoua; Mariotti, François; Martin, Pascal G P; Lasserre, Frédéric; Pineau, Thierry; Hermier, Dominique

    2011-10-01

    The pleiotropic effects of PPARα may include the regulation of amino acid metabolism. Nitric oxide (NO) is a key player in vascular homeostasis. NO synthesis may be jeopardized by a differential channeling of arginine toward urea (via arginase) versus NO (via NO synthase, NOS). This was studied in wild-type (WT) and PPARα-null (KO) mice fed diets containing either saturated fatty acids (COCO diet) or 18:3 n-3 (LIN diet). Metabolic markers of arginine metabolism were assayed in urine and plasma. mRNA levels of arginases and NOS were determined in liver. Whole-body NO synthesis and the conversion of systemic arginine into urea were assessed by using (15)N(2)-guanido-arginine and measuring urinary (15)NO(3) and [(15)N]-urea. PPARα deficiency resulted in a markedly lower whole-body NO synthesis, whereas the conversion of systemic arginine into urea remained unaffected. PPARα deficiency also increased plasma arginine and decreased citrulline concentration in plasma. These changes could not be ascribed to a direct effect on hepatic target genes, since NOS mRNA levels were unaffected, and arginase mRNA levels decreased in KO mice. Despite the low level in the diet, the nature of the fatty acids modulated some effects of PPARα deficiency, including plasma arginine and urea, which increased more in KO mice fed the LIN diet than in those fed the COCO diet. In conclusion, PPARα is largely involved in normal whole-body NO synthesis. This warrants further study on the potential of PPARα activation to maintain NO synthesis in the initiation of the metabolic syndrome.

  8. Expression pattern of a nuclear encoded mitochondrial arginine-ornithine translocator gene from Arabidopsis

    Directory of Open Access Journals (Sweden)

    Schneider Anja

    2003-01-01

    Full Text Available Abstract Background Arginine and citrulline serve as nitrogen storage forms, but are also involved in biosynthetic and catabolic pathways. Metabolism of arginine, citrulline and ornithine is distributed between mitochondria and cytosol. For the shuttle of intermediates between cytosol and mitochondria transporters present on the inner mitochondrial membrane are required. Yeast contains a mitochondrial translocator for ornithine and arginine, Ort1p/Arg11p. Ort1p/Arg11p is a member of the mitochondrial carrier family (MCF essential for ornithine export from mitochondria. The yeast arg11 mutant, which is deficient in Ort1p/Arg11p grows poorly on media lacking arginine. Results High-level expression of a nuclear encoded Arabidopsis thaliana homolog (AtmBAC2 of Ort1p/Arg11p was able to suppress the growth deficiency of arg11. RT-PCR analysis demonstrated expression of AtmBAC2 in all tissues with highest levels in flowers. Promoter-GUS fusions showed preferential expression in flowers, i.e. pollen, in the vasculature of siliques and in aborted seeds. Variable expression was observed in leaf vasculature. Induction of the promoter was not observed during the first two weeks in seedlings grown on media containing NH4NO3, arginine or ornithine as sole nitrogen sources. Conclusion AtmBAC2 was isolated as a mitochondrial transporter for arginine in Arabidopsis. The absence of expression in developing seeds and in cotyledons of seedlings indicates that other transporters are responsible for storage and mobilization of arginine in seeds.

  9. Transsulfuration pathway thiols and methylated arginines: the Hunter Community Study.

    Directory of Open Access Journals (Sweden)

    Arduino A Mangoni

    Full Text Available Serum homocysteine, when studied singly, has been reported to be positively associated both with the endogenous nitric oxide synthase inhibitor asymmetric dimethylarginine [ADMA, via inhibition of dimethylarginine dimethylaminohydrolase (DDAH activity] and with symmetric dimethylarginine (SDMA. We investigated combined associations between transsulfuration pathway thiols, including homocysteine, and serum ADMA and SDMA concentrations at population level.Data on clinical and demographic characteristics, medication exposure, C-reactive protein, serum ADMA and SDMA (LC-MS/MS, and thiols (homocysteine, cysteine, taurine, glutamylcysteine, total glutathione, and cysteinylglycine; capillary electrophoresis were collected from a sample of the Hunter Community Study on human ageing [n = 498, median age (IQR = 64 (60-70 years].REGRESSION ANALYSIS SHOWED THAT: a age (P = 0.001, gender (P = 0.03, lower estimated glomerular filtration rate (eGFR, P = 0.08, body mass index (P = 0.008, treatment with beta-blockers (P = 0.03, homocysteine (P = 0.02, and glutamylcysteine (P = 0.003 were independently associated with higher ADMA concentrations; and b age (P = 0.001, absence of diabetes (P = 0.001, lower body mass index (P = 0.01, lower eGFR (P<0.001, cysteine (P = 0.007, and glutamylcysteine (P < 0.001 were independently associated with higher SDMA concentrations. No significant associations were observed between methylated arginines and either glutathione or taurine concentrations.After adjusting for clinical, demographic, biochemical, and pharmacological confounders the combined assessment of transsulfuration pathway thiols shows that glutamylcysteine has the strongest and positive independent associations with ADMA and SDMA. Whether this reflects a direct effect of glutamylcysteine on DDAH activity (for ADMA and/or cationic amino acid transport requires further investigations.

  10. Arginine-rich cross-linking peptides with different SV40 nuclear localization signal content as vectors for intranuclear DNA delivery.

    Science.gov (United States)

    Bogacheva, Mariia; Egorova, Anna; Slita, Anna; Maretina, Marianna; Baranov, Vladislav; Kiselev, Anton

    2017-11-01

    The major barriers for intracellular DNA transportation by cationic polymers are their toxicity, poor endosomal escape and inefficient nuclear uptake. Therefore, we designed novel modular peptide-based carriers modified with SV40 nuclear localization signal (NLS). Core peptide consists of arginine, histidine and cysteine residues for DNA condensation, endosomal escape promotion and interpeptide cross-linking, respectively. We investigated three polyplexes with different NLS content (10 mol%, 50 mol% and 90 mol% of SV40 NLS) as vectors for intranuclear DNA delivery. All carriers tested were able to condense DNA, to protect it from DNAase I and were not toxic to the cells. We observed that cell cycle arrest by hydroxyurea did not affect transfection efficacy of NLS-modified carriers which we confirmed using quantitative confocal microscopy analysis. Overall, peptide carrier modified with 90 mol% of SV40 NLS provided efficient transfection and nuclear uptake in non-dividing cells. Thus, incorporation of NLS into arginine-rich cross-linking peptides is an adequate approach to the development of efficient intranuclear gene delivery vehicles. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Protein arginine methyltransferase 5 promotes lung cancer metastasis via the epigenetic regulation of miR-99 family/FGFR3 signaling.

    Science.gov (United States)

    Jing, Pengyu; Zhao, Nan; Ye, Mingxiang; Zhang, Yong; Zhang, Zhipei; Sun, Jianyong; Wang, Zhengxin; Zhang, Jian; Gu, Zhongping

    2018-07-28

    Protein arginine methyltransferase 5 (PRMT5) functions as a tumor initiator to regulate several cancer progressions, such as proliferation and apoptosis, by catalyzing the symmetrical dimethylation (me2s) of arginine residues within targeted molecules. However, the exact role of PRMT5-mediated metastasis in lung cancer is not fully understood. Here, we illustrated its potential effects in lung cancer metastasis in vivo and vitro. PRMT5 was frequently overexpressed in lung tumors, and its expression was positively related to tumor stages, lymphatic metastasis and poor outcome. In this model, PRMT5 repressed the transcription of the miR-99 family by symmetrical dimethylation of histone H4R3, which increased FGFR3 expression and in turn activated Erk1/2 and Akt, leading to cell growth and metastasis in lung cancer. Furthermore, loss of PRMT5 exerted anti-metastasis effects on lung cancer progression by blocking histone-modification of miR-99 family. Overall, this study provides new insights into the PRMT5/miR-99 family/FGFR3 axis in regulating lung cancer progression and identifies PRMT5 as a promising prognostic biomarker and therapeutic target. Copyright © 2018 The Author(s). Published by Elsevier B.V. All rights reserved.

  12. Handling of Solid Residues

    International Nuclear Information System (INIS)

    Medina Bermudez, Clara Ines

    1999-01-01

    The topic of solid residues is specifically of great interest and concern for the authorities, institutions and community that identify in them a true threat against the human health and the atmosphere in the related with the aesthetic deterioration of the urban centers and of the natural landscape; in the proliferation of vectorial transmitters of illnesses and the effect on the biodiversity. Inside the wide spectrum of topics that they keep relationship with the environmental protection, the inadequate handling of solid residues and residues dangerous squatter an important line in the definition of political and practical environmentally sustainable. The industrial development and the population's growth have originated a continuous increase in the production of solid residues; of equal it forms, their composition day after day is more heterogeneous. The base for the good handling includes the appropriate intervention of the different stages of an integral administration of residues, which include the separation in the source, the gathering, the handling, the use, treatment, final disposition and the institutional organization of the administration. The topic of the dangerous residues generates more expectation. These residues understand from those of pathogen type that are generated in the establishments of health that of hospital attention, until those of combustible, inflammable type, explosive, radio-active, volatile, corrosive, reagent or toxic, associated to numerous industrial processes, common in our countries in development

  13. Residues in food derived from animals

    International Nuclear Information System (INIS)

    Grossklaus, D.

    1989-01-01

    The first chapter presents a survey of fundamentals and methods of the detection and analysis of residues in food derived from animals, also referring to the resulting health hazards to man, and to the relevant legal provisions. The subsequent chapters have been written by experts of the Federal Health Office, each dealing with particular types of residues such as those of veterinary drugs, additives to animal feeds, pesticide residues, and with environmental pollutants and the contamination of animal products with radionuclides. (MG) With 35 figs., 61 tabs [de

  14. Amniotic Fluid Arginine from Gestational Weeks 13 to 15 Is a Predictor of Birth Weight, Length, and Head Circumference

    Directory of Open Access Journals (Sweden)

    Astrid Bjørke-Jenssen

    2017-12-01

    Full Text Available Arginine is a constituent of proteins and a precursor for polyamines and nitric oxide, and is essential for placentation, angiogenesis, and growth. Maternal plasma arginine concentrations are found to be lower in pregnancies complicated by fetal growth restriction, and arginine supplementation in later pregnancy is reported to increase birth weight. We measured arginine and the metabolites asymmetric dimethylarginine (ADMA and symmetric dimethylarginine (SDMA in the amniotic fluid obtained in pregnancy weeks 13 to 15 from 363 pregnancies with a documented normal outcome and related the concentrations to birth weight, length, and head circumference. Arginine was higher in the amniotic fluid from female (mean 40.8 (SD 10.6 µmol/L compared to male fetuses (37.4 (SD 11.2 µmol/L, p = 0.003. Despite the gender difference, arginine in the amniotic fluid from gestational weeks 13–15 was the strongest predictor for birth weight, length, and head circumference. ADMA was a strong predictor for birth weight and length, SDMA for birth weight, while Arg/ADMA and Arg/SDMA only predicted head circumference in multiple linear regression models. Due to increased arginine demands, pregnancy is considered a state of relative arginine deficiency. Our findings reflect the importance of a good maternal arginine status in early pregnancy, an observation that should be evaluated in an intervention study.

  15. Deprivation of L-Arginine Induces Oxidative Stress Mediated Apoptosis in Leishmania donovani Promastigotes: Contribution of the Polyamine Pathway

    Science.gov (United States)

    Mandal, Abhishek; Das, Sushmita; Roy, Saptarshi; Ghosh, Ayan Kumar; Sardar, Abul Hasan; Verma, Sudha; Saini, Savita; Singh, Ruby; Abhishek, Kumar; Kumar, Ajay; Mandal, Chitra; Das, Pradeep

    2016-01-01

    The growth and survival of intracellular parasites depends on the availability of extracellular nutrients. Deprivation of nutrients viz glucose or amino acid alters redox balance in mammalian cells as well as some lower organisms. To further understand the relationship, the mechanistic role of L-arginine in regulation of redox mediated survival of Leishmania donovani promastigotes was investigated. L-arginine deprivation from the culture medium was found to inhibit cell growth, reduce proliferation and increase L-arginine uptake. Relative expression of enzymes, involved in L-arginine metabolism, which leads to polyamine and trypanothione biosynthesis, were downregulated causing decreased production of polyamines in L-arginine deprived parasites and cell death. The resultant increase in reactive oxygen species (ROS), due to L-arginine deprivation, correlated with increased NADP+/NADPH ratio, decreased superoxide dismutase (SOD) level, increased lipid peroxidation and reduced thiol content. A deficiency of L-arginine triggered phosphatidyl serine externalization, a change in mitochondrial membrane potential, release of intracellular calcium and cytochrome-c. This finally led to DNA damage in Leishmania promastigotes. In summary, the growth and survival of Leishmania depends on the availability of extracellular L-arginine. In its absence the parasite undergoes ROS mediated, caspase-independent apoptosis-like cell death. Therefore, L-arginine metabolism pathway could be a probable target for controlling the growth of Leishmania parasites and disease pathogenesis. PMID:26808657

  16. Familial hypofibrinogenaemia associated with heterozygous substitution of a conserved arginine residue; Bbeta255 Arg-->His (Fibrinogen Merivale).

    Science.gov (United States)

    Maghzal, Ghassan J; Brennan, Stephen O; Fellowes, Andrew P; Spearing, Ruth; George, Peter M

    2003-02-21

    Sequencing of all three fibrinogen genes from an individual with hypofibrinogenaemia led to the identification of two new point mutations in the Bbeta gene. Family studies showed the mutations Bbeta255 Arg-->His (Fibrinogen Merivale) and Bbeta148 Lys-->Asn (Fibrinogen Merivale II) were on different alleles and that only the Bbeta255 Arg-->His mutation segregated with hypofibrinogenaemia. Three simple heterozygotes for this mutation had mean fibrinogen concentrations of 1.4 mg/ml, while heterozygotes for the Bbeta148 Lys-->Asn mutation had normal fibrinogen concentrations. ESI MS analysis of endoproteinase Asp-N digests of Bbeta chains showed that the Bbeta255 Arg-->His substitution was not expressed in plasma, confirming it as the cause of the hypofibrinogenaemia. The Bbeta148 Lys-->Asn chains, on the other hand, were equally expressed with wild-type Bbeta chains in simple heterozygotes. Genotype analysis failed to detect either substitution in 182 healthy controls. Arg(255) is located in the first strand of the five-stranded sheet that forms the main feature of the betaD domain and appears to form an essential H bond with Gly(414). Both the Arg and Gly are absolutely conserved, not only in all known Bbeta chains, but also in all homologous alphaE and gamma chains and in all fibrinogen-related proteins. Protein instability from loss of this contact could easily explain the association of this mutation with hypofibrinogenaemia.

  17. Caracterização Estrutural e da Capacidade de Absorção de Água em Bloco de Cimento com Adição de Resíduo de Pneu (Ecobloco = Water Absorption Capacity and Structural Characterization of Cement Block with Addition of Tire Residue (Ecobloco.

    Directory of Open Access Journals (Sweden)

    Maria da Conceição S. Gomes

    2007-12-01

    Full Text Available Foram feitos caracterizações estruturais com ensaios em corpo de prova, medidas granulométricas do resíduo, docimento, do pó de brita e da areia, e a medida da capacidade de absorção de água em blocos de cimento (chamados de ecoblocos com adição de 5%, 10%, 15%, 25% e 35% de resíduo de pneu, obtido por meio de raspagem de pneus automotivos inservíveis. A geometria de confecção dos ecoblocos foi projetada para serem encaixados no empilhamento vertical, requerendo o mínimo de massa de cimento para a confecção de parede de vedação. = Experiment for structural characterizations were made in test body as well as measurements of the capacity of water absorption in cement blocks (called ecoblocos with the addition of 5%, 10%, 15%, 25% and 35% of tire residue.These additions are obtained by means of worn out tire’s scratching. The ecoblocos´ design was projected for them to be inserted in the vertical piling up, requesting the minimum of mortar for the construction of walls.

  18. Maximizing Selective Cleavages at Aspartic Acid and Proline Residues for the Identification of Intact Proteins

    Science.gov (United States)

    Foreman, David J.; Dziekonski, Eric T.; McLuckey, Scott A.

    2018-04-01

    A new approach for the identification of intact proteins has been developed that relies on the generation of relatively few abundant products from specific cleavage sites. This strategy is intended to complement standard approaches that seek to generate many fragments relatively non-selectively. Specifically, this strategy seeks to maximize selective cleavage at aspartic acid and proline residues via collisional activation of precursor ions formed via electrospray ionization (ESI) under denaturing conditions. A statistical analysis of the SWISS-PROT database was used to predict the number of arginine residues for a given intact protein mass and predict a m/z range where the protein carries a similar charge to the number of arginine residues thereby enhancing cleavage at aspartic acid residues by limiting proton mobility. Cleavage at aspartic acid residues is predicted to be most favorable in the m/z range of 1500-2500, a range higher than that normally generated by ESI at low pH. Gas-phase proton transfer ion/ion reactions are therefore used for precursor ion concentration from relatively high charge states followed by ion isolation and subsequent generation of precursor ions within the optimal m/z range via a second proton transfer reaction step. It is shown that the majority of product ion abundance is concentrated into cleavages C-terminal to aspartic acid residues and N-terminal to proline residues for ions generated by this process. Implementation of a scoring system that weights both ion fragment type and ion fragment area demonstrated identification of standard proteins, ranging in mass from 8.5 to 29.0 kDa. [Figure not available: see fulltext.

  19. EVALUATION OF ANTIOXIDANT ACTIVITY OF SOME IMINES DERIVATIVES OF L-ARGININE.

    Science.gov (United States)

    Iacob, Andreea-Teodora; Drăgan, Maria; Constantin, Sandra; Lupaşcu, Florentina; Confederat, Luminiţa; Buron, F; Routier, S; Profire, Lenuţa

    2016-01-01

    L-Arginine is an a-amino acid which plays important roles in different diseases or processes, such as Alzheimer disease, inflammatory process, healing and tissue regeneration and it also could be useful as an anti-atherosclerotic agent. Considering the large amount of studies on the beneficial effects of different antioxidants, this paper is focused on the evaluation of the antioxidant potential of some imine derivatives, synthesized by the authors and described in a previous article. The evaluation of the antioxidant power was performed using phosphomolydenum-reducing antioxidant power (PRAP) and ferric reducing antioxidant power (FRAP) assays, tests described in the literature and which are used with some minor modifications. It was found that most of the imine derivatives are more active than the L-Arginine in the PPAP and FRAP assays. The most active derivative was the compound obtained by condensation of L-arginine with 2,3-dihydroxybenzaldehyde (2k) and 2-nitrobenzaldehyde (2g). Following the described protocol, some imine derivatives of L-arginine were evaluated in terms of antioxidant potential using in vitro methods. The most favorable influence was obtained by the aromatic substitution with nitro and hydroxyl, the corresponding derivatives being the most active derivatives compared to L-arginine.

  20. The impact of arginine-modified chitosan-DNA nanoparticles on the function of macrophages

    Energy Technology Data Exchange (ETDEWEB)

    Liu Lanxia; Bai Yuanyuan; Song Chunni; Zhu Dunwan; Song Liping; Zhang Hailing; Dong Xia; Leng Xigang, E-mail: lengxg@bme.org.c [Tianjin Key Laboratory of Biomedical Materials, Institute of Biomedical Engineering, Chinese Academy of Medical Sciences and Peking Union Medical College, Laboratory of Bioengineering (China)

    2010-06-15

    It has been demonstrated that incorporation of arginine moieties into chitosan significantly elevates the transgenic efficacy of the chitosan. However, little is known about the impact of arginine-modified chitosan on the function of macrophages, which play a vitally important role in the inflammatory response of the body to foreign substances, especially particulate substances. This study was designed to investigate the impact of arginine-modified chitosan/DNA nanoparticles on the function of the murine macrophage through observation of phagocytic activity and production of pro-inflammatory cytokines (IL-1{beta}, IL-6, IL-10, IL-12, and TNF-{alpha}). Results showed that both chitosan/DNA nanoparticles and arginine-modified chitosan/DNA nanoparticles, containing 20 {mu}g/mL DNA, were internalized by almost all the macrophages in contact. This led to no significant changes, compared to the non-exposure group, in production of cytokines and phagocytic activity of the macrophages 24 h post co-incubation, whereas exposure to LPS induced obviously elevated cytokine production and phagocytic activity, suggesting that incorporation of arginine moieties into chitosan does not have a negative impact on the function of the macrophages.

  1. L-Arginine metabolism in cardiovascular and renal tissue from hyper- and hypothyroid rats.

    Science.gov (United States)

    Rodríguez-Gómez, Isabel; Moliz, Juan N; Quesada, Andrés; Montoro-Molina, Sebastian; Vargas-Tendero, Pablo; Osuna, Antonio; Wangensteen, Rosemary; Vargas, Félix

    2016-03-01

    This study assessed the effects of thyroid hormones on the enzymes involved in l-arginine metabolism and the metabolites generated by the different metabolic pathways. Compounds of l-arginine metabolism were measured in the kidney, heart, aorta, and liver of euthyroid, hyperthyroid, and hypothyroid rats after 6 weeks of treatment. Enzymes studied were NOS isoforms (neuronal [nNOS], inducible [iNOS], and endothelial [eNOS]), arginases I and II, ornithine decarboxylase (ODC), ornithine aminotransferase (OAT), and l-arginine decarboxylase (ADC). Metabolites studied were l-arginine, l-citrulline, spermidine, spermine, and l-proline. Kidney heart and aorta levels of eNOS and iNOS were augmented and reduced (P hyperthyroid rats and was decreased in kidney and aorta of hypothyroid rats (P hyperthyroid rats and remained unchanged in all organs of hypothyroid rats. The substrate for these enzymes, l-arginine, was reduced (P hyperthyroid rats. Levels of ODC and spermidine, its product, were increased and decreased (P metabolic pathways. The changes recorded in the abundance of eNOS, arginases I and II, and ADC protein in renal and cardiovascular tissues may play a role in the hemodynamic and renal manifestations observed in thyroid disorders. Furthermore, the changes in ODC and spermidine might contribute to the changes in cardiac and renal mass observed in thyroid disorders. © 2015 by the Society for Experimental Biology and Medicine.

  2. A UV-induced mutation in neurospora that affects translational regulation in response to arginine

    International Nuclear Information System (INIS)

    Freitag, M.; Dighde, N.; Sachs, M.S.

    1996-01-01

    The Neurospora crassa arg-2 gene encodes the small subunit of arginine-specific carbamoyl phosphate synthetase. The levels of arg-2 mRNA and mRNA translation are negatively regulated by arginine. An upstream open reading frame (uORF) in the transcript's 5' region has been implicated in arginine-specific control. An arg-2-hph fusion gene encoding hygromycin phosphotransferase conferred arginine-regulated resistance to hygromycin when introduced into N. crassa. We used an arg-2-hph strain to select for UV-induced mutants that grew in the presence of hygromycin and arginine, and we isolated 46 mutants that had either of two phenotypes. One phenotype indicated altered expression of both arg-2-hph and arg-2 genes; the other, altered expression of arg-2-hph but not arg-2. One of the latter mutations, which was genetically closely linked to arg-2-hph, was recovered from the 5' region of the arg-2-hph gene using PCR Sequence analyses and transformation experiments revealed a mutation at uORF codon 12 (Asp to Asn) that abrogated negative regulation. Examination of the distribution of ribosomes on arg-2-hph transcripts showed that loss of regulation had a translational component, indicating the uORF sequence was important for Arg-specific translational control. Comparisons with other uORFs suggest common elements in translational control mechanisms

  3. Utilização de uréia no resíduo desidratado de vitivinícola associado à palma forrageira na alimentação de caprinos: consumo e digestibilidade de nutrientes Addition of urea to dehydrated vineyards residue, associated with forage cactus in goats feeding: intake and nutrient digestibility

    Directory of Open Access Journals (Sweden)

    Manuela Silva Libanio Tosto

    2008-10-01

    Full Text Available Avaliou-se a influência da adição de 0; 0,5; 1 ou 1,5% de uréia no resíduo desidratado de vitivinícolas - utilizado em associação a palma forrageira na alimentação de caprinos - no consumo e na digestibilidade dos nutrientes. Foram utilizados 24 caprinos machos castrados, sem padrão racial definido, com peso vivo médio de 18 kg, distribuídos em blocos ao acaso, de acordo com o peso vivo. O período experimental foi de 20 dias: 15 para adaptação e 5 para coleta. A adição de teores crescentes de uréia ao resíduo desidratado de vitivinícola possibilitou aumento do consumo de matéria seca (MS, matéria orgânica (MO, proteína bruta (PB e fibra em detergente neutro (FDN, expressos em kg/dia, %PV e em g/kgPV0,75. Observou-se consumo linear crescente de nutrientes digest��veis totais (NDT, carboidratos totais (CT e carboidratos não-fibrosos (CNF, em %PV e g/kgPV0,75. Não houve diferença significativa nos consumos de NDT, CT e CNF expressos em kg/dia, cujos valores médios foram 0,363; 0,575 e 0,258, respectivamente. Entretanto, a adição de uréia ao resíduo não influenciou os coeficientes de digestibildade de MS, MO e FDN (médias de 48,13; 46,08 e de 20,37%, respectivamente. Os coeficientes de digestibilidade de CNF apresentaram crescimento linear, enquanto os de PB apresentaram comportamento quadrático, com valor máximo de 48,93%, com a adição de 1,3% de uréia ao resíduo. O uso de uréia no resíduo desidratado de vitivinícola elevou linearmente o consumo de nutrientes, contudo, o nível de 1,3% é o mais indicado, pois promove melhor digestibilidade da proteína bruta de dietas contendo esse alimento alternativo.The effect of the addition of 0.0, 0.5, 1.0 and 1.5% of urea to dehydrated vineyards residue, associated to forage cactus palm in the feeding of goats on intake and nutrient digestibility was evaluated. Twenty-four castrated crossbred goats, without defined breed, with average 18 kg of BW were

  4. Characterization of Hospital Residuals

    International Nuclear Information System (INIS)

    Blanco Meza, A.; Bonilla Jimenez, S.

    1997-01-01

    The main objective of this investigation is the characterization of the solid residuals. A description of the handling of the liquid and gassy waste generated in hospitals is also given, identifying the source where they originate. To achieve the proposed objective the work was divided in three stages: The first one was the planning and the coordination with each hospital center, in this way, to determine the schedule of gathering of the waste can be possible. In the second stage a fieldwork was made; it consisted in gathering the quantitative and qualitative information of the general state of the handling of residuals. In the third and last stage, the information previously obtained was organized to express the results as the production rate per day by bed, generation of solid residuals for sampled services, type of solid residuals and density of the same ones. With the obtained results, approaches are settled down to either determine design parameters for final disposition whether for incineration, trituration, sanitary filler or recycling of some materials, and storage politics of the solid residuals that allow to determine the gathering frequency. The study concludes that it is necessary to improve the conditions of the residuals handling in some aspects, to provide the cleaning personnel of the equipment for gathering disposition and of security, minimum to carry out this work efficiently, and to maintain a control of all the dangerous waste, like sharp or polluted materials. In this way, an appreciable reduction is guaranteed in the impact on the atmosphere. (Author) [es

  5. Effect of L-arginine supplementation on immune responsiveness in patients with sickle cell disease.

    Science.gov (United States)

    Scavella, Arnette; Leiva, Lily; Monjure, Hanh; Zea, Arnold H; Gardner, Renee V

    2010-08-01

    L-arginine (L-Arg) is deficient in sickle cell disease (SSD) during vasoocclusion. We investigated possible causal relationship between L-Arg deficiency and immune dysfunction in SSD in steady-state. Fifteen patients with SSD in steady-state and 13 controls were studied. Plasma L-Arg levels were measured using liquid chromatography. T cell subsets and CD3zeta (CD3zeta) chain expression were analyzed using flow cytometry. Lymphocyte proliferative response to phytohemagglutinin (PHA) and production of IL-6 and interferon-gamma (IFN-gamma) were evaluated with and without L-Arg. SSD patients had significantly lower L-Arg levels than controls. CD3 and CD19 cell populations were comparable for both groups, but SSD patients had above normal numbers of natural killer cells (P = 0.06). Patients and controls exhibited significantly increased lymphocyte blastogenesis to PHA after introduction of L-Arg to cultures; response of patients was significantly greater than values for control individuals. Proliferative response to candida in SSD patients was significantly lower than in controls; L-Arg supplementation did not increase this response. L-Arg had no effect on blastogenic response to PPD and candida albicans. No effect was likewise seen in production of IL-6 and IFN-gamma after addition of L-Arg. CD3zeta chain expression increased after addition of L-Arg in both groups; differences were insignificant. L-Arg levels in steady-state SSD are significantly lower than in controls. L-Arg supplementation enhanced lymphocyte blastogenesis to PHA for both controls and patients, but not in response to antigen. There were no significant differences in CD3zeta chain expression although upregulation of expression occurred after L-Arg supplementation for both groups. (c) 2010 Wiley-Liss, Inc.

  6. Effects of a diabetes-specific enteral nutrition on nutritional and immune status of diabetic, obese, and endotoxemic rats: interest of a graded arginine supply.

    Science.gov (United States)

    Breuillard, Charlotte; Darquy, Sylviane; Curis, Emmanuel; Neveux, Nathalie; Garnier, Jean-Pierre; Cynober, Luc; De Bandt, Jean-Pascal

    2012-08-01

    Obese and type 2 diabetic patients present metabolic disturbance-related alterations in nonspecific immunity, to which the decrease in their plasma arginine contributes. Although diabetes-specific formulas have been developed, they have never been tested in the context of an acute infectious situation as can be seen in intensive care unit patients. Our aim was to investigate the effects of a diabetes-specific diet enriched or not with arginine in a model of infectious stress in a diabetes and obesity situation. As a large intake of arginine may be deleterious, this amino acid was given in graded fashion. Randomized, controlled experimental study. University research laboratory. Zucker diabetic fatty rats. Gastrostomized Zucker diabetic fatty rats were submitted to intraperitoneal lipopolysaccharide administration and fed for 7 days with either a diabetes-specific enteral nutrition without (G group, n=7) or with graded arginine supply (1-5 g/kg/day) (GA group, n=7) or a standard enteral nutrition (HP group, n=10). Survival rate was better in G and GA groups than in the HP group. On day 7, plasma insulin to glucose ratio tended to be lower in the same G and GA groups. Macrophage tumor necrosis factor-α (G: 5.0±1.1 ng/2×10⁶ cells·hr⁻¹; GA: 3.7±0.8 ng/2×10⁶ cells·hr⁻¹; and HP: 1.7±0.6 ng/2×10⁶ cells·hr⁻¹; p1.1 ng/2×10⁶ cells·hr⁻¹; GA: 5.1±1.0 ng/2×10⁶ cells·hr⁻¹; and HP: 1.0±0.5 nmol/2×10⁶ cells·hr⁻¹; pdiabetic obese and endotoxemic rats, a diabetes-specific formula leads to a lower mortality, a decreased insulin resistance, and an improvement in peritoneal macrophage function. Arginine supplementation has no additional effect. These data support the use of such disease-specific diets in critically ill diabetic and obese patients.

  7. Effect of L-arginine on the growth of Plasmodium falciparum and immune modulation of host cells.

    Science.gov (United States)

    Awasthi, Vikky; Chauhan, Rubika; Chattopadhyay, Debprasad; Das, Jyoti

    2017-01-01

    Malaria is a life-threatening disease caused by Plasmodium parasites. The life-cycle of Plasmodium species involves several stages both in mosquito and the vertebrate host. In the erythrocytic stage, Plasmodium resides inside the red blood cells (RBCs), where it meets most of its nutritional requirement by degrad- ing host's haemoglobin. L-arginine is required for growth and division of cells. The present study was aimed to demonstrate the effect of supplementation of different concentrations of L-arginine and L-citrulline on the growth of parasite, and effect of the culture supernatant on the host's peripheral blood mononuclear cells (PBMCs). To examine the effect of supplementation of L-arginine and L-citrulline, Plasmodium falciparum (3D7 strain) was cultured in RPMI 1640, L-arginine deficient RPMI 1640, and in different concentrations of L-arginine, and L-citrulline supplemented in arginine deficient RPMI 1640 medium. To have a holistic view of in vivo cell activation, the PBMCs isolated from healthy human host were cultured in the supernatant collected from P. falciparum culture. Growth of the parasite was greatly enhanced in L-arginine supplemented media and was found to be concentration dependent. However, parasite growth was compromised in L-citrulline supplemented and L-arginine deficient media. The supernatant collected from L-arginine supplemented parasite media (sArg) showed increased FOXP3 and interleukin-10 (IL-10) expression as compared to the supernatant collected from L-citrulline supple- mented parasite media (sCit). The in vitro culture results showed, decreased parasite growth, and decreased expression of programmed cell death-1 (PD-1) (a coinhibitory molecule) and IL-10 in the L-citrulline supplemented media as compared to L-arginine supplemented media. Hence, it was concluded that L-citrulline supplementation would be a better alternative than L-arginine to inhibit the parasite growth.

  8. Killing of Mycobacterium avium by lactoferricin peptides: improved activity of arginine- and D-amino-acid-containing molecules.

    Science.gov (United States)

    Silva, Tânia; Magalhães, Bárbara; Maia, Sílvia; Gomes, Paula; Nazmi, Kamran; Bolscher, Jan G M; Rodrigues, Pedro N; Bastos, Margarida; Gomes, Maria Salomé

    2014-06-01

    Mycobacterium avium causes respiratory disease in susceptible individuals, as well as disseminated infections in immunocompromised hosts, being an important cause of morbidity and mortality among these populations. Current therapies consist of a combination of antibiotics taken for at least 6 months, with no more than 60% overall clinical success. Furthermore, mycobacterial antibiotic resistance is increasing worldwide, urging the need to develop novel classes of antimicrobial drugs. One potential and interesting alternative strategy is the use of antimicrobial peptides (AMP). These are present in almost all living organisms as part of their immune system, acting as a first barrier against invading pathogens. In this context, we investigated the effect of several lactoferrin-derived AMP against M. avium. Short peptide sequences from both human and bovine lactoferricins, namely, hLFcin1-11 and LFcin17-30, as well as variants obtained by specific amino acid substitutions, were evaluated. All tested peptides significantly inhibited the axenic growth of M. avium, the bovine peptides being more active than the human. Arginine residues were found to be crucial for the display of antimycobacterial activity, whereas the all-d-amino-acid analogue of the bovine sequence displayed the highest mycobactericidal activity. These findings reveal the promising potential of lactoferricins against mycobacteria, thus opening the way for further research on their development and use as a new weapon against mycobacterial infections. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  9. Residual life management. Maintenance improvement

    International Nuclear Information System (INIS)

    Sainero Garcia, J.; Hevia Ruperez, F.

    1995-01-01

    The terms Residual Life Management, Life Cycle Management and Long-Term Management are synonymous with a concept which aims to establish efficient maintenance for the profitable and safe operation of a power plant for as long as possible. A Residual Life Management programme comprises a number of stages, of which Maintenance Evaluation focuses on how power plant maintenance practices allow the mitigation and control of component ageing. with this objective in mind, a methodology has been developed for the analysis of potential degradative phenomena acting on critical components in terms of normal power plant maintenance practices. This methodology applied to maintenance evaluation enables the setting out of a maintenance programme based on the Life Management concept, and the programme's subsequent up-dating to allow for new techniques and methods. Initial applications have shown that although, in general terms, power plant maintenance is efficient, the way in which Residual Life Management is approached requires changes in maintenance practices. These changes range from modifications to existing inspection and surveillance methods or the establishment of new ones, to the monitoring of trends or the performance of additional studies, the purpose of which is to provide an accurate evaluation of the condition of the installations and the possibility of life extension. (Author)

  10. Competitive metabolism of L-arginine: arginase as a therapeutic target in asthma☆

    Science.gov (United States)

    Bratt, Jennifer M.; Zeki, Amir A.; Last, Jerold A.; Kenyon, Nicholas J.

    2011-01-01

    Exhaled breath nitric oxide (NO) is an accepted asthma biomarker. Lung concentrations of NO and its amino acid precursor, L-arginine, are regulated by the relative expressions of the NO synthase (NOS) and arginase isoforms. Increased expression of arginase I and NOS2 occurs in murine models of allergic asthma and in biopsies of asthmatic airways. Although clinical trials involving the inhibition of NO-producing enzymes have shown mixed results, small molecule arginase inhibitors have shown potential as a therapeutic intervention in animal and cell culture models. Their transition to clinical trials is hampered by concerns regarding their safety and potential toxicity. In this review, we discuss the paradigm of arginase and NOS competition for their substrate L-arginine in the asthmatic airway. We address the functional role of L-arginine in inflammation and the potential role of arginase inhibitors as therapeutics. PMID:23554705

  11. l-arginine and l-NMMA for assessing cerebral endothelial dysfunction in ischaemic cerebrovascular disease

    DEFF Research Database (Denmark)

    Karlsson, William K; Sørensen, Caspar G; Kruuse, Christina

    2017-01-01

    Endothelial dysfunction (ED), in particular cerebral ED, may be an essential biomarker for ischaemic cerebrovascular disease. However, there is no consensus on methods to best estimate cerebral ED. In this systematic review, we evaluate the use of l-arginine and NG -monomethyl-l-arginine (l......-NMMA) for assessment of cerebral ED. A systematic search of PubMed, EMBASE and the Cochrane Library was done. We included studies investigating cerebrovascular response to l-arginine or l-NMMA in human subjects with vascular risk factors or ischaemic cerebrovascular disease. Seven studies (315 subjects) were eligible...... cerebrovascular disease. Inconsistencies in results were most likely due to variations in methods and included subject populations. In order to use cerebral ED as a prognostic marker, further studies are required to evaluate the association to cerebrovascular disease....

  12. Temporal Lob Epilepsi'sinde L-Arginine ve CaEDTA'nın Etkileri

    OpenAIRE

    NOYAN, Behzat

    2005-01-01

    Bu çalışmada, bir nitrik oksit (NO-) prekürsörü olan L-Arginine ve bir ekstrasellüler çinko şelatörü olan CaEDTA'nın pilokarpine HCl ile oluşturulan kısa süreli epileptik nöbet üzerine etkileri araştırıldı. Deney, nöbet kontrol (serum fizyolojik 10 µl, i.c.v., ve sonra 380 mg/kg pilokarpine HCl i.p.), L-Arginine (150 µg/10 µl, i.c.v.), CaEDTA (100 mM, 10 µl, i.c.v.), L-Arginine+CaEDTA olmak üzere 4 gruptan oluştu. Enjeksiyonlardan sonra iki saat boyunca nöbet davranışları gözlemlenen ...

  13. Synthesis and characterization of arginine-NIPAAm hybrid hydrogel as wound dressing: In vitro and in vivo study.

    Science.gov (United States)

    Wu, De-Qun; Zhu, Jie; Han, Hua; Zhang, Jun-Zhi; Wu, Fei-Fei; Qin, Xiao-Hong; Yu, Jian-Yong

    2018-01-01

    A multi-functional hybrid hydrogel P(M-Arg/NIPAAm) with temperature response, anti-protein adsorption and antibacterial properties was prepared and applied as wound dressing. The hydrogel was carried out by free radical copolymerization of methacrylate arginine (M-Arg) and N-isopropyl acrylamide (NIPAAm) monomers using N,N'-methylene bisacrylamide as a crosslinker, and ammonium persulfate/N,N,N', N'-tetramethylethylenediamine as the redox initiator. To endow the antimicrobial property, chlorhexidine diacetate (CHX) was preloaded into the hydrogel and polyhexamethylene guanidine phosphate (PHMG) was grafted on the hydrogel surface, respectively. The antimicrobial property of two series of hydrogels was evaluated and compared. The successful synthesis of M-Arg, PHMG and hydrogels was proved by 13 C NMR, 1 H NMR and FTIR spectroscopy. The hydrogel morphology characterized by scanning electron microscopy confirmed that the homogeneous porous and interconnected structures of the hydrogels. The swelling, protein adsorption property, in vitro release of CHX, antimicrobial assessment, cell viability as well as in vivo wound healing in a mouse model were studied. The results showed the nontoxicity and antimicrobial P(M-Arg/NIPAAm) hydrogel accelerated the full-thickness wound healing process and had the potential application in wound dressing. Despite the zwitterionic characteristic and biocompatible property of arginine based hydrogels, the brittle behavior and non-transparency still remain as a significant problem for wound dressing. Furthermore promoting the antibacterial property of the zwitterionic hydrogel is also necessary to prevent the bacterial colonization and subsequent wound infection. Therefore, we created a hybrid hydrogel combined methacrylate arginine (M-Arg) and N-isopropyl acrylamide (NIPAAm). NIPAAm improves transparency and mechanical property as well as acts as a temperature-response drug release system. Additionally, chlorhexidine (CHX) was preloaded

  14. Sided functions of an arginine-agmatine antiporter oriented in liposomes.

    Science.gov (United States)

    Tsai, Ming-Feng; Fang, Yiling; Miller, Christopher

    2012-02-28

    The arginine-dependent extreme acid resistance system helps enteric bacteria survive the harsh gastric environment. At the center of this multiprotein system is an arginine-agmatine antiporter, AdiC. To maintain cytoplasmic pH, AdiC imports arginine and exports its decarboxylated product, agmatine, resulting in a net extrusion of one "virtual proton" in each turnover. The random orientation of AdiC in reconstituted liposomes throws up an obstacle to quantifying its transport mechanism. To overcome this problem, we introduced a mutation, S26C, near the substrate-binding site. This mutant exhibits substrate recognition and pH-dependent activity similar to those of the wild-type protein but loses function completely upon reaction with thiol reagents. The membrane-impermeant MTSES reagent can then be used as a cleanly sided inhibitor to silence those S26C-AdiC proteins whose extracellular portion projects from the external side of the liposome. Alternatively, the membrane-permeant MTSEA and membrane-impermeant reducing reagent, TCEP, can be used together to inhibit proteins in the opposite orientation. This approach allows steady-state kinetic analysis of AdiC in a sided fashion. Arginine and agmatine have similar Michaelis-Menten parameters for both sides of the protein, while the extracellular side selects arginine over argininamide, a mimic of the carboxylate-protonated form of arginine, more effectively than does the cytoplasmic side. Moreover, the two sides of AdiC have different pH sensitivities. AdiC activity increases to a plateau at pH 4 as the extracellular side is acidified, while the cytoplasmic side shows an optimal pH of 5.5, with further acidification inhibiting transport. This oriented system allows more precise analysis of AdiC-mediated substrate transport than has been previously available and permits comparison to the situation experienced by the bacterial membrane under acid stress.

  15. The Metabolic Conversion of Arginine in the Rumen Wall and its Importance in Ruminant Nitrogen Metabolism

    Energy Technology Data Exchange (ETDEWEB)

    Harmeyer, J.; Kurelec, B.; Hill, H. [Department of Physiology, School of Veterinary Medicine, Hanover, Federal Republic of Germany (Germany)

    1968-07-01

    The functions of arginase and urease of the rumen wall were investigated in vitro and in vivo. Surviving ruminal mucosae of cattle were incubated for four hours. {sup 14}C-arginine-HCl, uniformly labelled, was added to the serosal side at a concentration of 10 pmol/mi. About 25% of the added arginine was used during the incubation by the ruminal tissue. In comparison with controls an increased amount of {sup 14}C-omithine, urea, and ammonia were formed in the mucosa and appeared on both sides. The increase was due to arginase and urease functions. It was estimated that about 50% of the urea formed by arginine breakdown were present at the mucosa side, mainly in the form of ammonia. Of the omithine simultaneously formed, 85% remained on the serosa side. Remarkable individual variations of omithine and urea formation were found from animal to animal. The in-vivo experiments were performed using goats with catheters placed in the right ruminal artery and vein. We injected 90 {mu}Ci of {sup 14}C-arginine into the ruminal artery. When 80 g of soluble starch were added to the rumen the activity and concentration of ornithine increased in the ruminal venous blood showing an arterial-venous difference. The radioactivity of urea in blood taken from the ruminal vein and the carotid artery did not show any difference. When starch was omitted from the rumen a comparable difference of omithine concentration was not found. It is assumed that the enzymes arginase and urease of the rumen wall are involved in nitrogen recycling processes. Blood arginine may be hydrolysed in the rumen wall forming urea and ornithine. Urea formed by arginine breakdown may be split to CO{sub 2} and ammonia. The experiments produced evidence that the ammonia formed preferably enters the rumen content. The nitrogen transfer through the rumen wall may be affected by varying activities of arginase. (author)

  16. Supplementation with rumen-protected L-arginine-HCl increased fertility in sheep with synchronized estrus.

    Science.gov (United States)

    de Chávez, Julio Agustín Ruiz; Guzmán, Adrian; Zamora-Gutiérrez, Diana; Mendoza, Germán David; Melgoza, Luz María; Montes, Sergio; Rosales-Torres, Ana María

    2015-08-01

    The aim of the present study was to evaluate the effects of L-arginine-HCl supplementation on ovulation rate, fertility, prolificacy, and serum VEGF concentrations in ewes with synchronized oestrus. Thirty Suffolk ewes with a mean body weight of 45 ± 3 kg and a mean body condition score (BCS) of 2.4 ± 0.28 were synchronized for estrus presentation with a progestin-containing sponge (20 mg Chronogest® CR) for 9 days plus PGF2-α (Lutalyse; Pfizer, USA) on day 7 after the insertion of the sponge. The ewes were divided into two groups; i.e., a control group (n = 15) that was fed on the native pasture (basal diet) and an L-arginine-HCl group (n = 15) that received 7.8 g of rumen-protected L-arginine-HCl from day 5 of the sponge insertion until day 25 after mating plus the basal diet. The L-arginine-HCl was administered daily via an esophageal probe between days 5 and 9 of the synchronization protocol and every third day subsequently. Blood samples were drawn from the jugular vein every 6 days throughout the entire experimental period. The results revealed that the L-arginine-HCl supplementation increased fertility during the synchronized estrus (P = 0.05). However, no effects were observed on the final BCS (P = 0.78), estrus presentation (P = 0.33), multiple ovulations (P = 0.24), prolificacy (P = 0.63), or serum VEGF concentration. In conclusion, L-arginine-HCl supplementation during the period used in this study increased fertility in sheep with synchronized estrus possibly due to improved embryo-fetal survival during early pregnancy.

  17. L-arginine fails to prevent ventricular remodeling and heart failure in the spontaneously hypertensive rat.

    Science.gov (United States)

    Brooks, Wesley W; Conrad, Chester H; Robinson, Kathleen G; Colucci, Wilson S; Bing, Oscar H L

    2009-02-01

    The effects of long-term oral administration of L-arginine, a substrate for nitric oxide (NO) production, on left ventricular (LV) remodeling, myocardial function and the prevention of heart failure (HF) was compared to the angiotensin-converting enzyme (ACE) inhibitor captopril in a rat model of hypertensive HF (aged spontaneously hypertensive rat (SHR)). SHRs and age-matched normotensive Wistar-Kyoto (WKY) rats were assigned to either no treatment, treatment with L-arginine (7.5 g/l in drinking water) or captopril (1 g/l in drinking water) beginning at 14 months of age, a time when SHRs exhibit stable compensated hypertrophy with no hemodynamic impairment; animals were studied at 23 months of age or at the time of HF. In untreated SHR, relative to WKY, there was significant LV hypertrophy, myocardial fibrosis, and isolated LV muscle performance and response to isoproterenol (ISO) were depressed; and, 7 of 10 SHRs developed HF. Captopril administration to six SHRs attenuated hypertrophy and prevented impaired inotropic responsiveness to ISO, contractile dysfunction, fibrosis, increased passive stiffness, and HF. In contrast, L-arginine administration to SHR increased LV hypertrophy and myocardial fibrosis while cardiac performance was depressed; and 7 of 9 SHRs developed HF. In WKY, L-arginine treatment but not captopril resulted in increased LV weight and the contractile response to ISO was blunted. Neither L-arginine nor captopril treatment of WKY changed fibrosis and HF did not occur. These data demonstrate that in contrast to captopril, long-term treatment with L-arginine exacerbates age-related cardiac hypertrophy, fibrosis, and did not prevent contractile dysfunction or the development of HF in aging SHR.

  18. Excess L-arginine restores endothelium-dependent relaxation impaired by monocrotaline pyrrole

    International Nuclear Information System (INIS)

    Cheng Wei; Oike, Masahiro; Hirakawa, Masakazu; Ohnaka, Keizo; Koyama, Tetsuya; Ito, Yushi

    2005-01-01

    The pyrrolizidine alkaloid plant toxin monocrotaline pyrrole (MCTP) causes pulmonary hypertension in experimental animals. The present study aimed to examine the effects of MCTP on the endothelium-dependent relaxation. We constructed an in vitro disease model of pulmonary hypertension by overlaying MCTP-treated bovine pulmonary artery endothelial cells (CPAEs) onto pulmonary artery smooth muscle cell-embedded collagen gel lattice. Acetylcholine (Ach) induced a relaxation of the control CPAEs-overlaid gels that were pre-contracted with noradrenaline, and the relaxation was inhibited by L-NAME, an inhibitor of NO synthase (NOS). In contrast, when MCTP-treated CPAEs were overlaid, the pre-contracted gels did not show a relaxation in response to Ach in the presence of 0.5 mM L-arginine. Expression of endothelial NOS protein, Ach-induced Ca 2+ transients and cellular uptake of L-[ 3 H]arginine were significantly smaller in MCTP-treated CPAEs than in control cells, indicating that these changes were responsible for the impaired NO production in MCTP-treated CPAEs. Since cellular uptake of L-[ 3 H]arginine linearly increased according to its extracellular concentration, we hypothesized that the excess concentration of extracellular L-arginine might restore NO production in MCTP-treated CPAEs. As expected, in the presence of 10 mM L-arginine, Ach showed a relaxation of the MCTP-treated CPAEs-overlaid gels. These results indicate that the impaired NO production in damaged endothelial cells can be reversed by supplying excess L-arginine

  19. Developmental changes of l-arginine transport at the blood-brain barrier in rats.

    Science.gov (United States)

    Tachikawa, Masanori; Hirose, Shirou; Akanuma, Shin-Ichi; Matsuyama, Ryo; Hosoya, Ken-Ichi

    2018-05-01

    l-Arginine is required for regulating synapse formation/patterning and angiogenesis in the developing brain. We hypothesized that this requirement would be met by increased transporter-mediated supply across the blood-brain barrier (BBB). Thus, the purpose of this work was to test the idea that elevation of blood-to-brain l-arginine transport across the BBB in the postnatal period coincides with up-regulation of cationic acid transporter 1 (CAT1) expression in developing brain capillaries. We found that the apparent brain-to-plasma concentration ratio (Kp, app) of l-arginine after intravenous administration during the first and second postnatal weeks was 2-fold greater than that at the adult stage. Kp, app of l-serine was also increased at the first postnatal week. In contrast, Kp, app of d-mannitol, a passively BBB-permeable molecule, did not change, indicating that increased transport of l-arginine and l-serine is not due to BBB immaturity. Double immunohistochemical staining of CAT1 and a marker protein, glucose transporter 1, revealed that CAT1 was localized on both luminal and abluminal membranes of brain capillary endothelial cells during the developmental and adult stages. A dramatic increase in CAT1 expression in the brain was seen at postnatal day 7 (P7) and day 14 (P14) and the expression subsequently decreased as the brain matured. In accordance with this, intense immunostaining of CAT1 was observed in brain capillaries at P7 and P14. These findings strongly support our hypothesis and suggest that the supply of blood-born l-arginine to the brain via CAT1 at the BBB plays a key role in meeting the elevated demand for l-arginine in postnatal brain. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Evolution of Substrate Specificity within a Diverse Family of [beta/alpha]-Barrel-fold Basic Amino Acid Decarboxylases X-ray Structure Determination of Enzymes with Specificity for L-Arginine and Carboxynorspermidine

    Energy Technology Data Exchange (ETDEWEB)

    Deng, Xiaoyi; Lee, Jeongmi; Michael, Anthony J.; Tomchick, Diana R.; Goldsmith, Elizabeth J.; Phillips, Margaret A. (Sungkyunkwan); (UTSMC)

    2010-08-26

    Pyridoxal 5{prime}-phosphate (PLP)-dependent basic amino acid decarboxylases from the {beta}/{alpha}-barrel-fold class (group IV) exist in most organisms and catalyze the decarboxylation of diverse substrates, essential for polyamine and lysine biosynthesis. Herein we describe the first x-ray structure determination of bacterial biosynthetic arginine decarboxylase (ADC) and carboxynorspermidine decarboxylase (CANSDC) to 2.3- and 2.0-{angstrom} resolution, solved as product complexes with agmatine and norspermidine. Despite low overall sequence identity, the monomeric and dimeric structures are similar to other enzymes in the family, with the active sites formed between the {beta}/{alpha}-barrel domain of one subunit and the {beta}-barrel of the other. ADC contains both a unique interdomain insertion (4-helical bundle) and a C-terminal extension (3-helical bundle) and it packs as a tetramer in the asymmetric unit with the insertions forming part of the dimer and tetramer interfaces. Analytical ultracentrifugation studies confirmed that the ADC solution structure is a tetramer. Specificity for different basic amino acids appears to arise primarily from changes in the position of, and amino acid replacements in, a helix in the {beta}-barrel domain we refer to as the 'specificity helix.' Additionally, in CANSDC a key acidic residue that interacts with the distal amino group of other substrates is replaced by Leu{sup 314}, which interacts with the aliphatic portion of norspermidine. Neither product, agmatine in ADC nor norspermidine in CANSDC, form a Schiff base to pyridoxal 5{prime}-phosphate, suggesting that the product complexes may promote product release by slowing the back reaction. These studies provide insight into the structural basis for the evolution of novel function within a common structural-fold.

  1. Roles of the conserved aspartate and arginine in the catalytic mechanism of an archaeal beta-class carbonic anhydrase.

    Science.gov (United States)

    Smith, Kerry S; Ingram-Smith, Cheryl; Ferry, James G

    2002-08-01

    The roles of an aspartate and an arginine, which are completely conserved in the active sites of beta-class carbonic anhydrases, were investigated by steady-state kinetic analyses of replacement variants of the beta-class enzyme (Cab) from the archaeon Methanobacterium thermoautotrophicum. Previous kinetic analyses of wild-type Cab indicated a two-step zinc-hydroxide mechanism of catalysis in which the k(cat)/K(m) value depends only on the rate constants for the CO(2) hydration step, whereas k(cat) also depends on rate constants from the proton transfer step (K. S. Smith, N. J. Cosper, C. Stalhandske, R. A. Scott, and J. G. Ferry, J. Bacteriol. 182:6605-6613, 2000). The recently solved crystal structure of Cab shows the presence of a buffer molecule within hydrogen bonding distance of Asp-34, implying a role for this residue in the proton transport step (P. Strop, K. S. Smith, T. M. Iverson, J. G. Ferry, and D. C. Rees, J. Biol. Chem. 276:10299-10305, 2001). The k(cat)/K(m) values of Asp-34 variants were decreased relative to those of the wild type, although not to an extent which supports an essential role for this residue in the CO(2) hydration step. Parallel decreases in k(cat) and k(cat)/K(m) values for the variants precluded any conclusions regarding a role for Asp-34 in the proton transfer step; however, the k(cat) of the D34A variant was chemically rescued by replacement of 2-(N-morpholino)propanesulfonic acid buffer with imidazole at pH 7.2, supporting a role for the conserved aspartate in the proton transfer step. The crystal structure of Cab also shows Arg-36 with two hydrogen bonds to Asp-34. Arg-36 variants had both k(cat) and k(cat)/K(m) values that were decreased at least 250-fold relative to those of the wild type, establishing an essential function for this residue. Imidazole was unable to rescue the k(cat) of the R36A variant; however, partial rescue of the kinetic parameter was obtained with guanidine-HCl indicating that the guanido group of this

  2. Efficacy L-Arginine In Patients With Nonalcoholic Steatohepatitis Associated With Metabolic Syndrome

    Directory of Open Access Journals (Sweden)

    Oleksandr Fediv

    2015-01-01

    Full Text Available Abstract Background and Purpose Recent research in the field of hematology indicate that among the many pathogenic mechanisms of development and progression of nonalcoholic steatohepatitis NASH which occurs on the background of the metabolic syndrome an important role is played by endothelial dysfunction and violations of haemocoagulation. The aim of this research was to study the effectiveness of L-arginine as it corrects endothelial dysfunction and disorders of homeostasis haemocoagulation link in patients with NASH associated with the metabolic syndrome. Subjects and Methods 128 patients with nonalcoholic steatohepatitis associated with metabolic syndrome were examined. Some patients 63 persons received standard treatment according to national guidelines. To another group 65 patients on the background of basic therapy L-arginine hydrochloride followed by transition to oral form of L-arginine aspartate was administered. Blood levels of stable nitrogen monoxide metabolites nitrites nitrates endothelin-1 and plasma recalcification time prothrombin time thrombin time activated partial thromboplastin time fibrinogen plasma level activity of antithrombin III and coagulation factor XIII potential activity of plasminogen plasma fibrinolytic blood activity were studied. Results Originally significantly increased levels of endothelin-1 decreased after the therapy in all studied groups but more noticeable changes in the group with L-arginine appointment were observed p0.05. In the studied groups normalization of stable nitrogen monoxide metabolites after treatment was also noticed. Significant p0.05 increase in all haemocoagulation time characteristics and activities of antithrombin-III and factor XIII was found. The positive effect of L-arginine on blood fibrinolytic activity was noted. Discussion and Conclusion Combined therapy of nonalcoholic steatohepatitis associated with metabolic syndrome with a differentiated degreeal L-arginine assignment by

  3. Arginine vasopressin stimulates phosphoinositide turnover in an enriched rat Leydig cell preparation

    DEFF Research Database (Denmark)

    Nielsen, J.R.; Hansen, Harald S.; Jensen, B.

    1989-01-01

    An enriched rat Leydig cell preparation was preincubated with [C]arachidonic acid. Stimulation of the cells with arginine vasopressin (AVP) (1 µM) for 2 min caused a significant increase in labelled phosphatidic acid and a significant fall in radioactivity in phosphatidylinositol and phosphatidyl......An enriched rat Leydig cell preparation was preincubated with [C]arachidonic acid. Stimulation of the cells with arginine vasopressin (AVP) (1 µM) for 2 min caused a significant increase in labelled phosphatidic acid and a significant fall in radioactivity in phosphatidylinositol...

  4. Arginine as an adjuvant to chemotherapy improves clinical outcome in active tuberculosis

    DEFF Research Database (Denmark)

    Schön, T; Elias, D; Moges, F

    2003-01-01

    Nitric oxide (NO) is involved in the host defence against tuberculosis (TB). Patients with TB exhibit increased catabolism and reduced energy intake. Thus the hypothesis for this study was that restoring a relative deficiency in the amino acid arginine, the substrate for mycobactericidal NO produ......Nitric oxide (NO) is involved in the host defence against tuberculosis (TB). Patients with TB exhibit increased catabolism and reduced energy intake. Thus the hypothesis for this study was that restoring a relative deficiency in the amino acid arginine, the substrate for mycobactericidal...... virus-negative patients with active tuberculosis, most likely mediated by increased production of nitric oxide....

  5. Management of NORM Residues

    International Nuclear Information System (INIS)

    2013-06-01

    The IAEA attaches great importance to the dissemination of information that can assist Member States in the development, implementation, maintenance and continuous improvement of systems, programmes and activities that support the nuclear fuel cycle and nuclear applications, and that address the legacy of past practices and accidents. However, radioactive residues are found not only in nuclear fuel cycle activities, but also in a range of other industrial activities, including: - Mining and milling of metalliferous and non-metallic ores; - Production of non-nuclear fuels, including coal, oil and gas; - Extraction and purification of water (e.g. in the generation of geothermal energy, as drinking and industrial process water; in paper and pulp manufacturing processes); - Production of industrial minerals, including phosphate, clay and building materials; - Use of radionuclides, such as thorium, for properties other than their radioactivity. Naturally occurring radioactive material (NORM) may lead to exposures at some stage of these processes and in the use or reuse of products, residues or wastes. Several IAEA publications address NORM issues with a special focus on some of the more relevant industrial operations. This publication attempts to provide guidance on managing residues arising from different NORM type industries, and on pertinent residue management strategies and technologies, to help Member States gain perspectives on the management of NORM residues

  6. NOS3 is involved in the increased protein and arginine metabolic response in muscle during early endotoxemia in mice

    NARCIS (Netherlands)

    Luiking, Yvette C.; Hallemeesch, Marcella M.; Lamers, Wouter H.; Deutz, Nicolaas E. P.

    2005-01-01

    Sepsis is a severe catabolic condition. The loss of skeletal muscle protein mass is characterized by enhanced release of the amino acids glutamine and arginine, which (in)directly affects interorgan arginine and the related nitric oxide (NO) synthesis. To establish whether changes in muscle amino

  7. Functional variation in the arginine vasopressin 2 receptor as a modifier of human plasma von Willebrand factor levels

    DEFF Research Database (Denmark)

    Nossent, Anne Yaël; Robben, J H; Deen, P M T

    2010-01-01

    SUMMARY OBJECTIVES: Stimulation of arginine vasopressin 2 receptor (V2R) with arginine vasopressin (AVP) results in a rise in von Willebrand factor (VWF) and factor VIII plasma levels. We hypothesized that gain-of-function variations in the V2R gene (AVPR2) would lead to higher plasma levels of V...

  8. L-arginine enhances cell proliferation and reduces apoptosis in human endometrial RL95-2 cells

    Science.gov (United States)

    L-arginine is considered to be one of the most versatile amino acids due to the fact that it serves as a precursor for many important molecules in cellular physiology. When supplemented in the diet, L-arginine can increase the number of implantation sites in mice and rats, suggesting an effect at th...

  9. Heritability and genetic variance for citrulline, arginine and lycopene content in a diverse set of watermelon cultigens

    Science.gov (United States)

    Citrulline, arginine, and lycopene are naturally occurring compounds found in watermelon, Citrullus lanatus (Thumb) Matsum & Nakai, with beneficial effects on plant growth and human health. This study evaluated seven commercial cultivars and one breeding line for citrulline, arginine, and lycopene c...

  10. L-arginine supplementation enhances exhaled NO, breath condensate VEGF, and headache at 4,342 m.

    Science.gov (United States)

    Mansoor, Jim K; Morrissey, Brian M; Walby, William F; Yoneda, Ken Y; Juarez, Maya; Kajekar, Radhika; Severinghaus, John W; Eldridge, Marlowe W; Schelegle, Edward S

    2005-01-01

    We examined the effect of dietary supplementation with L-arginine on breath condensate VEGF, exhaled nitric oxide (NO), plasma erythropoietin, symptoms of acute mountain sickness, and respiratory related sensations at 4,342 m through the course of 24 h in seven healthy male subjects. Serum L-arginine levels increased in treated subjects at time 0, 8, and 24 h compared with placebo, indicating the effectiveness of our treatment. L-arginine had no significant effect on overall Lake Louise scores compared with placebo. However, there was a significant increase in headache within the L-arginine treatment group at 12 h compared with time 0, a change not seen in the placebo condition between these two time points. There was a trend (p = 0.087) toward greater exhaled NO and significant increases in breath condensate VEGF with L-arginine treatment, but no L-arginine effect on serum EPO. These results suggest that L-arginine supplementation increases HIF-1 stabilization in the lung, possibly through a NO-dependent pathway. In total, our observations indicate that L-arginine supplementation is not beneficial in the prophylactic treatment of AMS.

  11. Cyolane residues in milk of lactating goats

    International Nuclear Information System (INIS)

    Zayed, S.M.A.D.; Osman, A.; Fakhr, I.M.I.

    1981-01-01

    Consecutive feeding of lactating goats with 14 C-alkyl labelled cyolane for 5 days at dietary levels 8 and 16 ppm resulted in the appearance of measurable insecticide residues in milk (0.02-0.04 mg/kg). The residue levels were markedly reduced after a withdrawal period of 7 days. Analysis of urine and milk residues showed the presence of similar metabolites in addition to the parent compound. The major part of the residue consisted of mono-, diethyl phosphate and 2 hydrophilic unknown metabolites. The erythrocyte cholinesterase activity was reduced to about 50% after 24 hours whereas the plasma enzyme was only slightly affected. The animals remained symptom-free during the experimental period. (author)

  12. The human neonatal small intestine has the potential for arginine synthesis; developmental changes in the expression of arginine-synthesizing and -catabolizing enzymes

    Directory of Open Access Journals (Sweden)

    Ruijter Jan M

    2008-11-01

    Full Text Available Abstract Background Milk contains too little arginine for normal growth, but its precursors proline and glutamine are abundant; the small intestine of rodents and piglets produces arginine from proline during the suckling period; and parenterally fed premature human neonates frequently suffer from hypoargininemia. These findings raise the question whether the neonatal human small intestine also expresses the enzymes that enable the synthesis of arginine from proline and/or glutamine. Carbamoylphosphate synthetase (CPS, ornithine aminotransferase (OAT, argininosuccinate synthetase (ASS, arginase-1 (ARG1, arginase-2 (ARG2, and nitric-oxide synthase (NOS were visualized by semiquantitative immunohistochemistry in 89 small-intestinal specimens. Results Between 23 weeks of gestation and 3 years after birth, CPS- and ASS-protein content in enterocytes was high and then declined to reach adult levels at 5 years. OAT levels declined more gradually, whereas ARG-1 was not expressed. ARG-2 expression increased neonatally to adult levels. Neurons in the enteric plexus strongly expressed ASS, OAT, NOS1 and ARG2, while varicose nerve fibers in the circular layer of the muscularis propria stained for ASS and NOS1 only. The endothelium of small arterioles expressed ASS and NOS3, while their smooth-muscle layer expressed OAT and ARG2. Conclusion The human small intestine acquires the potential to produce arginine well before fetuses become viable outside the uterus. The perinatal human intestine therefore resembles that of rodents and pigs. Enteral ASS behaves as a typical suckling enzyme because its expression all but disappears in the putative weaning period of human infants.

  13. Protein arginine methyltransferase 5 is an essential component of the hypoxia-inducible factor 1 signaling pathway

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Ji-Hong; Choi, Yong-Joon; Cho, Chung-Hyun [Department of Pharmacology, Ischemic/Hypoxic Disease Institute, Seoul National University College of Medicine, 103 Daehak-ro, Jongno-gu, Seoul 110-799 (Korea, Republic of); Park, Jong-Wan, E-mail: parkjw@snu.ac.kr [Department of Pharmacology, Ischemic/Hypoxic Disease Institute, Seoul National University College of Medicine, 103 Daehak-ro, Jongno-gu, Seoul 110-799 (Korea, Republic of)

    2012-02-10

    Highlights: Black-Right-Pointing-Pointer HIF-1{alpha} is expressed PRMT5-dependently in hypoxic cancer cells. Black-Right-Pointing-Pointer The HIF-1 regulation of hypoxia-induced genes is attenuated in PRMT5-knocked-down cells. Black-Right-Pointing-Pointer The de novo synthesis of HIF-1{alpha} depends on PRMT5. Black-Right-Pointing-Pointer PRMT5 is involved in the HIF-1{alpha} translation initiated by 5 Prime UTR of HIF-1{alpha} mRNA. -- Abstract: Protein arginine methyltransferase 5 (PRMT5) is an enzyme that transfers one or two methyl groups to the arginine residues of histones or non-histone proteins, and that plays critical roles in cellular processes as diverse as receptor signaling and gene expression. Furthermore, PRMT5 is highly expressed in tumors, where it may be associated with tumor growth. Although much research has been conducted on PRMT5, little is known regarding its role in adaption to hypoxia. As hypoxia-inducible factor 1 (HIF-1) is a key player in hypoxic response, we examined the possible involvement of PRMT5 in the HIF-1 signaling pathway. Of the siRNAs targeting PRMT1-8, only PRMT5 siRNA attenuated the hypoxic induction of HIF-1{alpha} in A549 cells, and this result was reproducible in all three cancer cell lines examined. PRMT5 knock-down also repressed the promoter activities and the transcript levels of HIF-1-governed genes. Mechanistically, de novo synthesis of HIF-1{alpha} protein was reduced in PRMT5-knocked-down A549 cells, and this was rescued by PRMT5 restoration. In contrast, HIF-1{alpha} transcription, RNA processing, and protein stability were unaffected by PRMT5 knock-down. Furthermore, PRMT5 was found to be essential for the HIF-1{alpha} translation initiated by the 5 Prime UTR of HIF-1{alpha} mRNA. Given our results and previous reports, we believe that PRMT5 probably promotes tumor growth by stimulating cell proliferation and by participating in the construction of a tumor-favorable microenvironment via HIF-1 activation.

  14. Protein arginine methyltransferase 5 is an essential component of the hypoxia-inducible factor 1 signaling pathway

    International Nuclear Information System (INIS)

    Lim, Ji-Hong; Choi, Yong-Joon; Cho, Chung-Hyun; Park, Jong-Wan

    2012-01-01

    Highlights: ► HIF-1α is expressed PRMT5-dependently in hypoxic cancer cells. ► The HIF-1 regulation of hypoxia-induced genes is attenuated in PRMT5-knocked-down cells. ► The de novo synthesis of HIF-1α depends on PRMT5. ► PRMT5 is involved in the HIF-1α translation initiated by 5′ UTR of HIF-1α mRNA. -- Abstract: Protein arginine methyltransferase 5 (PRMT5) is an enzyme that transfers one or two methyl groups to the arginine residues of histones or non-histone proteins, and that plays critical roles in cellular processes as diverse as receptor signaling and gene expression. Furthermore, PRMT5 is highly expressed in tumors, where it may be associated with tumor growth. Although much research has been conducted on PRMT5, little is known regarding its role in adaption to hypoxia. As hypoxia-inducible factor 1 (HIF-1) is a key player in hypoxic response, we examined the possible involvement of PRMT5 in the HIF-1 signaling pathway. Of the siRNAs targeting PRMT1–8, only PRMT5 siRNA attenuated the hypoxic induction of HIF-1α in A549 cells, and this result was reproducible in all three cancer cell lines examined. PRMT5 knock-down also repressed the promoter activities and the transcript levels of HIF-1-governed genes. Mechanistically, de novo synthesis of HIF-1α protein was reduced in PRMT5-knocked-down A549 cells, and this was rescued by PRMT5 restoration. In contrast, HIF-1α transcription, RNA processing, and protein stability were unaffected by PRMT5 knock-down. Furthermore, PRMT5 was found to be essential for the HIF-1α translation initiated by the 5′ UTR of HIF-1α mRNA. Given our results and previous reports, we believe that PRMT5 probably promotes tumor growth by stimulating cell proliferation and by participating in the construction of a tumor-favorable microenvironment via HIF-1 activation.

  15. Interaction of the Small GTPase Cdc42 with Arginine Kinase Restricts White Spot Syndrome Virus in Shrimp.

    Science.gov (United States)

    Xu, Ji-Dong; Jiang, Hai-Shan; Wei, Tian-Di; Zhang, Ke-Yi; Wang, Xian-Wei; Zhao, Xiao-Fan; Wang, Jin-Xing

    2017-03-01

    Many types of small GTPases are widely expressed in eukaryotes and have different functions. As a crucial member of the Rho GTPase family, Cdc42 serves a number of functions, such as regulating cell growth, migration, and cell movement. Several RNA viruses employ Cdc42-hijacking tactics in their target cell entry processes. However, the function of Cdc42 in shrimp antiviral immunity is not clear. In this study, we identified a Cdc42 protein in the kuruma shrimp ( Marsupenaeus japonicus ) and named it Mj Cdc42. Mj Cdc42 was upregulated in shrimp challenged by white spot syndrome virus (WSSV). The knockdown of Mj Cdc42 and injection of Cdc42 inhibitors increased the proliferation of WSSV. Further experiments determined that Mj Cdc42 interacted with an arginine kinase ( Mj AK). By analyzing the binding activity and enzyme activity of Mj AK and its mutant, Δ Mj AK, we found that Mj AK could enhance the replication of WSSV in shrimp. Mj AK interacted with the envelope protein VP26 of WSSV. An inhibitor of AK activity, quercetin, could impair the function of Mj AK in WSSV replication. Further study demonstrated that the binding of Mj Cdc42 and Mj AK depends on Cys 271 of Mj AK and suppresses the WSSV replication-promoting effect of Mj AK. By interacting with the active site of Mj AK and suppressing its enzyme activity, Mj Cdc42 inhibits WSSV replication in shrimp. Our results demonstrate a new function of Cdc42 in the cellular defense against viral infection in addition to the regulation of actin and phagocytosis, which has been reported in previous studies. IMPORTANCE The interaction of Cdc42 with arginine kinase plays a crucial role in the host defense against WSSV infection. This study identifies a new mechanism of Cdc42 in innate immunity and enriches the knowledge of the antiviral innate immunity of invertebrates. Copyright © 2017 American Society for Microbiology.

  16. Protective effect of Mimosa pudica L. in an L-arginine model of acute necrotising pancreatitis in rats.

    Science.gov (United States)

    Kaur, Jagdeep; Sidhu, Shabir; Chopra, Kanwaljit; Khan, M U

    2016-07-01

    Mimosa pudica is used in traditional medicine for treating various disorders such as inflammatory conditions, diarrhoea, insomnia, alopecia, urogenital infections and wounds. The present study investigated the effect of M. pudica extract (MPE) on L-arginine-induced acute necrotising pancreatitis in rats. The ethanolic extract of M. pudica leaves was studied for the presence of quercetin and gallic acid using high-performance liquid chromatography. Four groups were employed-normal control rats, L-arginine control rats (two intraperitoneal [i.p.] injections of 2 g/kg at an interval of 1 h), MPE-treated rats (400 mg/kg orally) and melatonin-treated rats (positive control 10 mg/kg i.p.), which were further divided into subgroups according to time points (24 h, 3 days and 14 days). Serum amylase, lipase, tumour necrosis factor-α (TNF-α), pancreatic amylase, nucleic acid content, protein, transforming growth factor-β1 (TGF-β1), thiobarbituric reactive substances, glutathione, nitrite/nitrate, collagen content and histopathological examination were carried out. MPE significantly improved acute necrotising pancreatitis by modulating diagnostic markers of pancreatitis such as serum lipase and pancreatic amylase, inflammation (TNF-α), and oxidative and nitrosative stress. Moreover, MPE administration induced regenerative changes in the pancreas evidenced by increased levels of pancreatic proteins, nucleic acid content and histopathology report. In addition, MPE improved TGF-β1 and collagen levels thereby preventing fibrosis. The current investigation indicates the novel role of MPE in reducing the severity of acute necrotising pancreatitis by plausible mechanisms such as anti-inflammatory and anti-fibrotic activity and by promoting repair and regeneration of the pancreas.

  17. L-arginine supplementation improves responses to injury and inflammation in dextran sulfate sodium colitis.

    Directory of Open Access Journals (Sweden)

    Lori A Coburn

    Full Text Available Inflammatory bowel disease (IBD, consisting of Crohn's disease and ulcerative colitis (UC, results in substantial morbidity and is difficult to treat. New strategies for adjunct therapies are needed. One candidate is the semi-essential amino acid, L-arginine (L-Arg, a complementary medicine purported to be an enhancer of immunity and vitality in the lay media. Using dextran sulfate sodium (DSS as a murine colonic injury and repair model with similarities to human UC, we assessed the effect of L-Arg, as DSS induced increases in colonic expression of the y(+ cationic amino acid transporter 2 (CAT2 and L-Arg uptake. L-Arg supplementation improved the clinical parameters of survival, body weight loss, and colon weight, and reduced colonic permeability and the number of myeloperoxidase-positive neutrophils in DSS colitis. Luminex-based multi-analyte profiling demonstrated that there was a marked reduction in proinflammatory cytokine and chemokine expression with L-Arg treatment. Genomic analysis by microarray demonstrated that DSS-treated mice supplemented with L-Arg clustered more closely with mice not exposed to DSS than to those receiving DSS alone, and revealed that multiple genes that were upregulated or downregulated with DSS alone exhibited normalization of expression with L-Arg supplementation. Additionally, L-Arg treatment of mice with DSS colitis resulted in increased ex vivo migration of colonic epithelial cells, suggestive of increased capacity for wound repair. Because CAT2 induction was sustained during L-Arg treatment and inducible nitric oxide (NO synthase (iNOS requires uptake of L-Arg for generation of NO, we tested the effect of L-Arg in iNOS(-/- mice and found that its benefits in DSS colitis were eliminated. These preclinical studies indicate that L-Arg supplementation could be a potential therapy for IBD, and that one mechanism of action may be functional enhancement of iNOS activity.

  18. Residual-stress measurements

    Energy Technology Data Exchange (ETDEWEB)

    Ezeilo, A N; Webster, G A [Imperial College, London (United Kingdom); Webster, P J [Salford Univ. (United Kingdom)

    1997-04-01

    Because neutrons can penetrate distances of up to 50 mm in most engineering materials, this makes them unique for establishing residual-stress distributions non-destructively. D1A is particularly suited for through-surface measurements as it does not suffer from instrumental surface aberrations commonly found on multidetector instruments, while D20 is best for fast internal-strain scanning. Two examples for residual-stress measurements in a shot-peened material, and in a weld are presented to demonstrate the attractive features of both instruments. (author).

  19. The Effects of Pretreatment with Various Doses of L-Arginine on Cisplatin-Induced Nephropathy of Male Rats

    Directory of Open Access Journals (Sweden)

    B Rasoulian

    2016-09-01

    Full Text Available Introduction: Cisplatin is a widely used anti-cancer drug, which its application is limited by nephrotoxicity. In this study, the effect of pretreatment with different l-arginine doses on Cisplatin-induced renal functional injury was investigated. Methods: 63 male rats were divided into 7 groups: In groups 3, 4, 5 and 6, 60 min before the Cisplatin injection (5mg/kg; L-Arginine with doses of 50,100,200 or 400mg/kg was injected, respectively. In group7, normal saline was injected before Cisplatin administration. In groups 1 and 2, normal saline was injected instead of Cisplatin. In group 2, 60min before normal saline injection, 400mg/kg L-Arginine was administered and in group1, instead of L-arginine, normal saline was injected too. Injections were intraperitoneal. 72h after Cisplatin injection, blood sampling and plasma separation were done. Urine sample was collected 24 hours before blood sampling by metabolic cage. The mean of plasma urea and creatinine levels and creatinine clearance (ml/day.kg and fractional excretion of Na (FENa, % were compared among different groups as renal functional parameters. Results: In comparison to group 7, L-arginine injection in a dose of 400mg/kg led to significant amelioration of all parameters. 200 mg/kg L-arginine administration led to significant decrease in plasma urea level and FENa. 100mg/kg L-arginine caused significant improvement in fractional excretion of sodium. L-arginine injection with 50mg/kg dose, significantly ameliorate all renal function tests instead of creatinine clearance. Conclusion: Pretreatment with L-arginine administration with 400 or 50 mg/kg doses, respectively, had the highest effect on reducing Cisplatin-induced nephropathy. L-arginine injection with intermediate doses i.e. 200 or 100 mg/kg had less effect in reducing Cisplatin-induced nephropathy and it needs more investigations.

  20. Metabolically induced heteroplasmy shifting and L-arginine treatment reduce the energetic defect in a neuronal-like model of MELAS

    Science.gov (United States)

    Desquiret-Dumas, Valerie; Gueguen, Naig; Barth, Magalie; Chevrollier, Arnaud; Hancock, Saege; Wallace, Douglas C; Amati-Bonneau, Patrizia; Henrion, Daniel; Bonneau, Dominique; Reynier, Pascal; Procaccio, Vincent

    2012-01-01

    The m.3243A>G variant in the mitochondrial tRNALeu (UUR) gene is a common mitochondrial DNA (mtDNA) mutation. Phenotypic manifestations depend mainly on the heteroplasmy, i.e. the ratio of mutant to normal mtDNA copies. A high percentage of mutant mtDNA is associated with a severe, life-threatening neurological syndrome known as MELAS (mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes). MELAS is described as a neurovascular disorder primarily affecting the brain and blood vessels, but the pathophysiology of the disease is poorly understood. We developed a series of cybrid cell lines at two different mutant loads: 70% and 100% in the nuclear background of a neuroblastoma cell line (SH-SY5Y). We investigated the impact of the mutation on the metabolism and mitochondrial respiratory chain activity of the cybrids. The m.3243A>G mitochondrial mutation induced a metabolic switch towards glycolysis in the neuronal cells and produced severe defects in respiratory chain assembly and activity. We used two strategies to compensate for the biochemical defects in the mutant cells: one consisted of lowering the glucose content in the culture medium, and the other involved the addition of L-arginine. The reduction of glucose significantly shifted the 100% mutant cells towards the wild-type, reaching a 90% mutant level and restoring respiratory chain complex assembly. The addition of L-arginine, a nitric oxide (NO) donor, improved complex I activity in the mutant cells in which the defective NO metabolism had led to a relative shortage of NO. Thus, metabolically induced heteroplasmy shifting and L-arginine therapy may constitute promising therapeutic strategies against MELAS. PMID:22306605

  1. Role of the L-citrulline/L-arginine cycle in iNANC nerve-mediated nitric oxide production and airway smooth muscle relaxation in allergic asthma

    NARCIS (Netherlands)

    Maarsingh, Ham; Leusink, John; Zaagsma, Johan; Meurs, Herman

    2006-01-01

    Nitric oxide synthase (NOS) converts L-arginine into nitric oxide (NO) and L-Citrulline. In NO-producing cells, L-citrulline can be recycled to L-arginine in a two-step reaction involving argininosuccinate synthase (ASS) and -lyase (ASL). In guinea pig trachea, L-arginine is a limiting factor in

  2. Alternative additives; Alternative additiver

    Energy Technology Data Exchange (ETDEWEB)

    2007-08-15

    In this project a number of industrial and agricultural waste products have been characterised and evaluated in terms of alkali-getter performance. The intended use is for biomass-fired power stations aiming at reducing corrosion or slagging related problems. The following products have been obtained, characterised and evaluated: 1) Brewery draff 2) Danish de-gassed manure 3) Paper sludge 4) Moulding sand 5) Spent bleaching earth 6) Anorthosite 7) Sand 8) Clay-sludge. Most of the above alternative additive candidates are deemed unsuitable due to insufficient chemical effect and/or expensive requirements for pre-treatment (such as drying and transportation). 3 products were selected for full-scale testing: de-gassed manure, spent bleaching earth and clay slugde. The full scale tests were undertaken at the biomass-fired power stations in Koege, Slagelse and Ensted. Spent bleaching earth (SBE) and clay sludge were the only tested additive candidates that had a proven ability to react with KCl, to thereby reduce Cl-concentrations in deposits, and reduce the deposit flux to superheater tubes. Their performance was shown to nearly as good as commercial additives. De-gassed manure, however, did not evaluate positively due to inhibiting effects of Ca in the manure. Furthermore, de-gassed manure has a high concentration of heavy metals, which imposes a financial burden with regard to proper disposal of the ash by-products. Clay-sludge is a wet clay slurring, and drying and transportation of this product entails substantial costs. Spent bleaching does not require much pre-treatment and is therefore the most promising alternative additive. On the other hand, bleaching earth contains residual plant oil which means that a range of legislation relating to waste combustion comes into play. Not least a waste combustion fee of 330 DKK/tonne. For all alternative (and commercial) additives disposal costs of the increase ash by-products represents a significant cost. This is

  3. Content of non-esterified fatty acids in the blood plasma of rabbits with acute arginine pancreatitis and its correction

    Directory of Open Access Journals (Sweden)

    Y. F. Rivis

    2013-01-01

    Full Text Available The aim of this work was to study the content of non-esterified fatty acids in plasma and liver of rabbits with acute arginine pancreatitis and its correction by linseed oil. The experiment was carried out on male rabbits breed gray giant with live weight 3.8–4.0 kg. The material for the study was sampled from blood and liver. Lipids from plasma and liver were extracted with a mixture of chloroform and methanol. After that the non-esterified fatty acids were isolated and methylated. Methyl esters of fatty acids were studied by the gas-liquid chromatography with the chromatograph ''Chrom 5'' (Prague,CzechRepublic. We have found that the content of non-esterified fatty acids decreases in the blood plasma and liver of rabbits with the acute arginine pancreatitis. It takes place at the expense of a reduce of saturated fatty acids with odd and even number of carbon atoms in a chain, monounsaturated fatty acids of the families ω-7 and ω-9 and polyunsaturated fatty acids of the families ω-3 and ω-6. That may indicate a greater use of non-esterified fatty acids for energy metabolism and esterification of lipids. We suppose that this is a consequence of the probable increase in content of non-esterified and esterified cholesterol in the rabbits’ blood plasma. Those processes provoke the cholesterol deposits in blood vessels and therefore cardiovascular diseases. We tried to influence on the processes by addition of linseed oil to the rabbits diet. We have found that in the linseed oil-fed rabbits the content of non-esterified fatty acids decreases at the expense of saturated fatty acids with odd and even number of carbon atoms in a chain and monounsaturated fatty acids of the families ω-7 and ω-9 inblood plasma and liver of the rabbits with acute arginine pancreatitis. Furthermore the levels of non-esterified polyunsaturated fatty acids of ω-3 family increase in the rabbits’ plasma and liver. As this takes place the ratio of non

  4. Designing with residual materials

    NARCIS (Netherlands)

    Walhout, W.; Wever, R.; Blom, E.; Addink-Dölle, L.; Tempelman, E.

    2013-01-01

    Many entrepreneurial businesses have attempted to create value based on the residual material streams of third parties. Based on ‘waste’ materials they designed products, around which they built their company. Such activities have the potential to yield sustainable products. Many of such companies

  5. Arginine and vitamin E improve the immune response after a Salmonella challenge in broiler chicks

    Science.gov (United States)

    Two experiments were conducted to evaluate the effects of arginine (ARG), vitamin E (VE), and mannanoligosaccharide (MOS) on the immune response and clearance of Salmonella in broiler chickens. In each experiment, chicks were randomly distributed into 4 groups: antibiotic-free diet (negative contro...

  6. Structural alterations in rat myocardium induced by chronic l-arginine and l-NAME supplementation

    Directory of Open Access Journals (Sweden)

    Amal Abdussalam Ali A. Hmaid

    2018-03-01

    Full Text Available Structural changes affecting cardiomyocyte function may contribute to the pathophysiological remodeling underlying cardiac function impairment. Recent reports have shown that endogenous nitric oxide (NO plays an important role in this process. In order to examine the role of NO in cardiomyocyte remodeling, male rats were acclimated to room temperature (22 ± 1 °C or cold (4 ± 1 °C and treated with 2.25% l-arginine·HCl or 0.01% l-NAME (Nω-nitro-l-arginine methyl ester·HCl for 45 days. Untreated groups served as controls. Right heart ventricles were routinely prepared for light microscopic examination. Stereological estimations of volume densities of cardiomyocytes, surrounding blood vessels and connective tissue, as well as the morphometric measurements of cardiomyocyte diameters were performed. Tissue sections were also analyzed for structural alterations. We observed that both l-arginine and l-NAME supplementation induced cardiomyocyte hypertrophy, regardless of ambient temperature. However, cardiomyocyte hypertrophy was associated with fibrosis and extra collagen deposition only in the l-NAME treated group. Taken together, our results suggest that NO has a modulatory role in right heart ventricle remodeling by coordinating hypertrophy of cardiomyocytes and fibrous tissue preventing cardiac fibrosis. Keywords: Cardiomyocyte, Cardiac hypertrophy, l-Arginine, l-NAME, Myocardium

  7. Thermal, FT–IR and SHG efficiency studies of L-arginine doped KDP ...

    Indian Academy of Sciences (India)

    TECS

    popular due to their applications in frequency converters, electro-optic switching and .... parameters of dehydration process of pure and L-arginine doped KDP crystals were ... action, R a gas constant, and a the heating rate in deg.C.min. –1.

  8. Calcium alpha-ketoglutarate administration to malnourished hemodialysis patients improves plasma arginine concentrations.

    Science.gov (United States)

    Riedel, E; Hampl, H; Steudle, V; Nündel, M

    1996-01-01

    Calcium alpha-ketoglutarate administration to 24 malnourished hemodialysis patients for 1 year leads to a significant increase in plasma concentrations of L-arginine from 53.6 +/- 18.3 (compared to a healthy control group: 87.5 +/- 27.3) to 71.1 +/- 15.9 mumol/l (p calcium alpha-ketoglutarate administration.

  9. Effect of in ovo injection with L-arginine on productive and ...

    African Journals Online (AJOL)

    p2492989

    Significant decreases were recorded in blood serum cholesterol, total lipids ... 2% and 3% arginine, resulted in a significant improvement in the productive ... Various factors play important roles in birds in influencing hatchability efficiency and growth ... in the yolk sac may not be sufficient to supply in the maintenance energy.

  10. Friend of Prmt1, a novel chromatin target of protein arginine methyltransferases

    NARCIS (Netherlands)

    T.B. van Dijk (Thamar); N. Gillemans (Nynke); C. Stein (Claudia); P. Fanis (Pavlos); J.A.A. Demmers (Jeroen); M.P.C. van de Corput (Mariëtte); J. Essers (Jeroen); F.G. Grosveld (Frank); U.M. Bauer (Uta-Maria); J.N.J. Philipsen (Sjaak)

    2010-01-01

    textabstractWe describe the isolation and characterization of Friend of Prmt1 (Fop), a novel chromatin target of protein arginine methyltransferases. Human Fop is encoded by C1orf77, a gene of previously unknown function. We show that Fop is tightly associated with chromatin, and that it is modified

  11. Allevation of Oxidative Damages Induced by Salinity in Cress (Lepidium sativum by Pretreating with Arginine

    Directory of Open Access Journals (Sweden)

    E Asadi karam

    2015-05-01

    Full Text Available Salinity is one of the main stresses that have negative effectcs on seedling growth, and plant production. It inhibits growth of plants through disturbance of the balance between production of ROS and antioxidant defense mechanism which results in oxidative stress. Because, arginine is a vital regulator of physiological and developmental processes the effect of different concentrations of arginine pretreatment of the plant on alleviation of oxidative stress induced by salt 50 and 100Mm NaCl was investigated. Arginine pretreatment increased chlorophyll a, b, carotenoid and seedling growth under salinity condition. Results also showed that salt stress increased proline, protein, H2O2, soluble sugar and the activity of ascorbate peroxidase, guaiacol peroxidase and catalase. Pretreatment of plants with Arg reduced proline, soluble sugar, H2O2 and antioxidant enzymes activity content significantly. The conclusion is that in garden cress plants, pretreatment with concentration of 5 µM and 10 μM arginine may protect cress under salinity stress, probably through the contracting with ROS and or induction of anti-oxidative enzymes

  12. Conformationally Constrained Peptidomimetics as Inhibitors of the Protein Arginine Methyl Transferases

    DEFF Research Database (Denmark)

    Knuhtsen, Astrid; Legrand, Baptiste; Van der Poorten, Olivier

    2016-01-01

    Protein arginine N-methyl transferases (PRMTs) belong to a family of enzymes that modulate the epigenetic code through modifications of histones. In the present study, peptides emerging from a phage display screening were modified in the search for PRMT inhibitors through substitution with non-pr...

  13. Arginine metabolism is altered in adults with A-B + ketosis-prone diabetes

    Science.gov (United States)

    A-B + ketosis-prone diabetes (KPD) is a subset of type 2 diabetes in which patients have severe but reversible B cell dysfunction of unknown etiology. Plasma metabolomic analysis indicates that abnormal arginine metabolism may be involved. The objective of this study was to determine the relation be...

  14. Evidence for arginine as the endogenous precursor of necines in heliotropium.

    Science.gov (United States)

    Birecka, H; Birecki, M; Frohlich, M W

    1987-05-01

    In pyrrolizidine alkaloid-bearing Heliotropium angiospermum and H. indicum shoots exposed, in the light, to (14)C-labeled CO(2) for 44 hours, the incorporation of (14)C into 1,2-epoxy-1-hydroxymethylpyrrolizidine and retronecine amounted to 0.23 and 0.15%, respectively, of the total carbon assimilated. Treatment of the shoots with alpha-dl-difluoromethylornithine, the specific ornithine decarboxylase inhibitor, at 1 to 2 millimolar had no effect on (14)C incorporation into the necines. In contrast, alpha-dl-difluoromethylarginine, the specific arginine decarboxylase inhibitor, prevented the incorporation of (14)C into the necines of both species; the inhibitor did not affect the absolute incorporation of (14)C from exogenous [1,4-(14)C] putrescine in either species. Thus, arginine is the only apparent endogenous precursor of the putrescine channeled into pyrrolizidines, at least in these two Heliotropium species that exhibited a relatively much higher in vitro activity of arginine decarboxylase than of ornithine decarboxylase. However, within 28 hours after administration, not only exogenous l-[5-(14)C]arginine, but also exogenous l-[5-(14)C]ornithine exhibited significant incorporation of their label into the necines, incorporation that could be partially prevented by both inhibitors. Neither inhibitor affected the rates of (14)C-labeled CO(2) assimilation, transformation of labeled assimilates into ethanol-insoluble compounds, or the very high degree of conversion of the introduced amino acids into other compounds. Methodology related to alkaloid biosynthetic studies is discussed.

  15. Evidence for Arginine as the Endogenous Precursor of Necines in Heliotropium1

    Science.gov (United States)

    Birecka, Helena; Birecki, Mieczyslaw; Frohlich, M. W.

    1987-01-01

    In pyrrolizidine alkaloid-bearing Heliotropium angiospermum and H. indicum shoots exposed, in the light, to 14C-labeled CO2 for 44 hours, the incorporation of 14C into 1,2-epoxy-1-hydroxymethylpyrrolizidine and retronecine amounted to 0.23 and 0.15%, respectively, of the total carbon assimilated. Treatment of the shoots with α-dl-difluoromethylornithine, the specific ornithine decarboxylase inhibitor, at 1 to 2 millimolar had no effect on 14C incorporation into the necines. In contrast, α-dl-difluoromethylarginine, the specific arginine decarboxylase inhibitor, prevented the incorporation of 14C into the necines of both species; the inhibitor did not affect the absolute incorporation of 14C from exogenous [1,4-14C] putrescine in either species. Thus, arginine is the only apparent endogenous precursor of the putrescine channeled into pyrrolizidines, at least in these two Heliotropium species that exhibited a relatively much higher in vitro activity of arginine decarboxylase than of ornithine decarboxylase. However, within 28 hours after administration, not only exogenous l-[5-14C]arginine, but also exogenous l-[5-14C]ornithine exhibited significant incorporation of their label into the necines, incorporation that could be partially prevented by both inhibitors. Neither inhibitor affected the rates of 14C-labeled CO2 assimilation, transformation of labeled assimilates into ethanol-insoluble compounds, or the very high degree of conversion of the introduced amino acids into other compounds. Methodology related to alkaloid biosynthetic studies is discussed. PMID:16665402

  16. Diurnal changes in polyamine content, arginine and ornithine decarboxylase, and diamine oxidase in tobacco leaves

    Czech Academy of Sciences Publication Activity Database

    Gemperlová, Lenka; Nováková, Marie; Vaňková, Radomíra; Eder, Josef; Cvikrová, Milena

    2006-01-01

    Roč. 57, č. 6 (2006), s. 1413-1421 ISSN 0022-0957 R&D Projects: GA ČR GA206/03/0369 Institutional research plan: CEZ:AV0Z50380511 Keywords : Arginine decarboxylase * diamine oxidase * ornithine decarboxylase Subject RIV: ED - Physiology Impact factor: 3.630, year: 2006

  17. Erythrocytes L-arginine y+ transporter inhibition by N-ethylmaleimide in ice-bath.

    Science.gov (United States)

    Pinheiro da Costa, Bartira Ercília; de Almeida, Priscilla Barcellos; Conceição, Ioná Rosine; Antonello, Ivan Carlos Ferreira; d'Avila, Domingos O; Poli-de-Figueiredo, Carlos Eduardo

    2010-11-01

    Erythrocytes L: -arginine uptake is conveyed by y+ and y+L membrane transport systems. Pre-incubation with N-ethylmaleimide for 10 min at 37°C inhibits the y+ system. The aim of this study was to determine the ideal pre-incubation temperature in evaluating y+ and y+L systems. Cells were pre-incubated with or without N-ethylmaleimide for 10 min at 4°C and 37°C. L: -Arginine uptake was quantified by radioisotope and standard erythrocytes membrane flux methodology. Results demonstrate that erythrocytes L: -arginine content is depleted by pre-incubation at 37°C for 10 min, thus changing the V (max) measurement. The inhibitory effect of N-ethylmaleimide pre-incubation was temperature independent and already complete after 1 min of incubation. No significant difference in kinetic parameters was detected between cells pre-incubated at 37°C or 4°C, under zero-trans conditions. In conclusion, we suggest that measurement of erythrocytes L: -arginine uptake by y+ and y+L systems could be carried out without N-ethylmaleimide pre-incubation at 37°C.

  18. Mutations in protein N-arginine methyltransferases are not the cause of FTLD-FUS

    NARCIS (Netherlands)

    Ravenscroft, T.A.; Baker, M.C.; Rutherford, N.J.; Neumann, M.; Mackenzie, I.R.; Josephs, K.A.; Boeve, B.F.; Petersen, R.; Halliday, G.M.; Kril, J.; van Swieten, J.C.; Seeley, W.W.; Dickson, D.W.; Rademakers, R.

    2013-01-01

    The nuclear protein fused in sarcoma (FUS) is found in cytoplasmic inclusions in a subset of patients with the neurodegenerative disorder frontotemporal lobar degeneration (FTLD-FUS). FUS contains a methylated arginine-glycine-glycine domain that is required for transport into the nucleus. Recent

  19. Feed supplementation with arginine and zinc on antioxidant status and inflammatory response in challenged weanling piglets

    Directory of Open Access Journals (Sweden)

    Nadia Bergeron

    2017-09-01

    Full Text Available Although supplementing the diet with zinc oxide and arginine is known to improve growth in weanling piglets, the mechanism of action is not well understood. We measured the antioxidant status and inflammatory response in 48 weanling castrated male piglets fed diets supplemented with or without zinc oxide (2,500 mg Zn oxide per kg and arginine (1% starting at the age of 20 days. The animals were injected with lipopolysaccharide (100 μg/kg on day 5. Half of them received another injection on day 12. Blood samples were taken just before and 6, 24 and 48 h after injection and the mucosa lining the ileum was recovered following euthanizing on days 7 and 14. Zinc supplementation increased reduced and total glutathione (GSH (reduced and total during days 5 to 7 and arginine decreased oxidized GSH measured on days 5 and 12 and the ratio of total antioxidant capacity to total oxidative status during days 12 to 14. Zinc decreased plasma malondialdehyde measured on days 5 and 12 and serum haptoglobin measured on day 12 and increased both metallothionein-1 expression and total antioxidant capacity measured in the ileal mucosa on day 14. Tumour necrosis factor α concentration decreased from days 5 to 12 (all effects were significant at P < 0.05. This study shows that the zinc supplement reduced lipid oxidation and lipopolysaccharide-induced inflammation during the post-weaning period, while the arginine supplementation had only a limited effect.

  20. The Effect of Pumpkin ( Cucurbita pepo L) Seeds and L-Arginine ...

    African Journals Online (AJOL)

    The present study aimed to examine the effect of pumpkin (Cucurbita pepo L.) seeds supplementation on androgenic diet-induced atherosclerosis. Rat were divided into two main groups , normal control and atherogenic control rats , each group composed of three subgroups one of them supplemented with 2% arginine in ...

  1. L-Arginine deficiency causes airway hyperresponsiveness after the late asthmatic reaction

    NARCIS (Netherlands)

    Maarsingh, H.; Bossenga, B. E.; Bos, I. S. T.; Volders, H. H.; Zaagsma, J.; Meurs, H.

    Peroxynitrite has been shown to be crucially involved in airway hyperresponsiveness (AHR) after the late asthmatic reaction (LAR). Peroxynitrite production may result from simultaneous synthesis of nitric oxide (NO) and superoxide by inducible NO-synthase (iNOS) at low L-arginine concentrations.

  2. Periodical low eggshell temperatures during incubation and post hatch dietary arginine supplementation

    NARCIS (Netherlands)

    Afsarian, O.; Shahir, M.H.; Akhlaghi, A.; Lotfolahian, H.; Hoseini, A.; Lourens, A.

    2016-01-01

    An experiment was conducted to evaluate the effects of a periodically low eggshell temperature exposure during incubation and dietary supplementation of arginine on performance, ascites incidence, and cold tolerance acquisition in broilers. A total of 2,400 hatching eggs were randomly assigned to

  3. Nutritional supplementation with arginine protects radiation-induced effects: an experimental study

    Energy Technology Data Exchange (ETDEWEB)

    Pinto, Flavia Cristina Morone, E-mail: fcmorone@gmail.com [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil); Campos-Silva, Pamella; Souza, Diogo Benchimol de; Costa, Waldemar Silva; Sampaio, Francisco Jose Barcellos [Universidade do Estado do Rio de Janeiro (UERJ), Rio de Janeiro, RJ (Brazil)

    2016-10-15

    Purpose: To investigate the protective effect of L-arginine on the prostate (nonneoplasic) of rats with radiation-induced injury. Methods: Twenty-nine Wistar rats, male adult, allocated into three groups: Control group (C) was not exposed to irradiation (n=10); Radiated group (R) had undergone pelvic irradiation (n=10); Supplemented and radiated group (R+S) had undergone pelvic irradiation plus L-arginine supplementation (n=9). The animals were observed for signs of toxicity. After euthanization, the prostate was dissected under magnification and stained by hematoxylin and eosin to study acinar structures and stained with Picrosirius red for collagen analysis. Results: After radiation exposure, all animals presented diarrhea, but supplementation with L-arginine reduced this effect. The weight gain in the R+S group was significantly higher than in the C and R groups. In the R+S group the collagen density and the prostate acinar area was similar to the R and C groups. Epithelial height was significantly reduced in group R compared with group C (p<0.0001). When comparing the group R+S with R, a statistical difference was observed to be present (p<0.0001). Conclusions: Pelvic radiation promotes systemic effects and some structural modifications in the ventral prostate of rats. These modifications can be prevented by oral supplementation with L-arginine. (author)

  4. l-Arginine Pathway Metabolites Predict Need for Intra-operative Shunt During Carotid Endarterectomy

    DEFF Research Database (Denmark)

    Szabo, P; Lantos, J; Nagy, L

    2016-01-01

    lactate levels were increased during reperfusion (p = .02). The median pre-operative concentration of l-arginine was lower in patients requiring an intra-operative shunt than in patients without need of shunt (median: 30.3 μmol/L [interquartile range 24.4-34.4 μmol/L] vs. 57.6 μmol/L [interquartile range...

  5. Growth and characterization of pure and doped NLO L-arginine ...

    Indian Academy of Sciences (India)

    Administrator

    NLO; SHG; solution growth; LAA. 1. Introduction. L-arginine phosphate monohydrate (LAP) was first repor- ted by Xu et al (1983) as a promising nonlinear optical. (NLO) material. LAP is nearly three times more nonlinear than KDP. Monaco et al (1987) reported the formation of. LAP and its chemical analogs from the strongly ...

  6. Ensemble Kalman filtering with residual nudging

    KAUST Repository

    Luo, X.

    2012-10-03

    Covariance inflation and localisation are two important techniques that are used to improve the performance of the ensemble Kalman filter (EnKF) by (in effect) adjusting the sample covariances of the estimates in the state space. In this work, an additional auxiliary technique, called residual nudging, is proposed to monitor and, if necessary, adjust the residual norms of state estimates in the observation space. In an EnKF with residual nudging, if the residual norm of an analysis is larger than a pre-specified value, then the analysis is replaced by a new one whose residual norm is no larger than a pre-specified value. Otherwise, the analysis is considered as a reasonable estimate and no change is made. A rule for choosing the pre-specified value is suggested. Based on this rule, the corresponding new state estimates are explicitly derived in case of linear observations. Numerical experiments in the 40-dimensional Lorenz 96 model show that introducing residual nudging to an EnKF may improve its accuracy and/or enhance its stability against filter divergence, especially in the small ensemble scenario.

  7. Ensemble Kalman filtering with residual nudging

    Directory of Open Access Journals (Sweden)

    Xiaodong Luo

    2012-10-01

    Full Text Available Covariance inflation and localisation are two important techniques that are used to improve the performance of the ensemble Kalman filter (EnKF by (in effect adjusting the sample covariances of the estimates in the state space. In this work, an additional auxiliary technique, called residual nudging, is proposed to monitor and, if necessary, adjust the residual norms of state estimates in the observation space. In an EnKF with residual nudging, if the residual norm of an analysis is larger than a pre-specified value, then the analysis is replaced by a new one whose residual norm is no larger than a pre-specified value. Otherwise, the analysis is considered as a reasonable estimate and no change is made. A rule for choosing the pre-specified value is suggested. Based on this rule, the corresponding new state estimates are explicitly derived in case of linear observations. Numerical experiments in the 40-dimensional Lorenz 96 model show that introducing residual nudging to an EnKF may improve its accuracy and/or enhance its stability against filter divergence, especially in the small ensemble scenario.

  8. L-arginine and glycine supplementation in the repair of the irradiated colonic wall of rats.

    Science.gov (United States)

    de Aguiar Picanço, Etiene; Lopes-Paulo, Francisco; Marques, Ruy G; Diestel, Cristina F; Caetano, Carlos Eduardo R; de Souza, Mônica Vieira Mano; Moscoso, Gabriela Mendes; Pazos, Helena Maria F

    2011-05-01

    Radiotherapy is widely used for cancer treatment but has harmful effects. This study aimed to assess the effects of L-arginine and glycine supplementation on the colon wall of rats submitted to abdominal irradiation. Forty male Wistar rats were randomly divided into four groups: I-healthy, II-irradiated with no amino acid supplementation, III-irradiated and supplemented with L-arginine, and IV-irradiated and supplemented with glycine. The animals received supplementation for 14 days, with irradiation being applied on the eighth day of the experiment. All animals underwent laparotomy on the 15th day for resection of a colonic segment for stereologic analysis. Parametric and nonparametric tests were used for statistical analysis, with the level of significance set at p ≤0.05. Stereologic analysis showed that irradiation induced a reduction of the total volume of the colon wall of group II and III animals compared to healthy controls, but not of group IV animals supplemented with glycine. The mucosal layer of the irradiated animals of all groups was reduced compared to healthy group I animals, but supplementation with L-arginine and glycine was effective in maintaining the epithelial surface of the mucosal layer. The present results suggest that glycine supplementation had a superior effect on the irradiated colon wall compared to L-arginine supplementation since it was able to maintain the thickness of the wall and the epithelial surface of the mucosa, whereas L-arginine maintained the partial volume of the epithelium and the epithelial surface, but not the total volume of the intestinal wall.

  9. The effect of L-Arginine on the brain tissue of stressed rats

    Directory of Open Access Journals (Sweden)

    Batoul Ebadi

    2010-01-01

    Full Text Available Introduction: This study was conducted to determine the possible beneficial results of L-arginine on prefrontal cortex of rats which impressed by immobilization stress to define the synchronous impression of stress and nitric oxide (NO on evolution of prefrontal cortex of rats after birth. Methods: Forty-eight one month, male Wistar rats were divided into two groups: stressed and non-stressed. L-Arginine (200 mg/kg as a NO synthase (NOS inducer and L-NAME (2O mg/kg were injected intraperitonealy (IP and 7- nitroindazde (25 mg/kg as non-specific was injected subcutaneously (S.C. for 4 weeks. The kind of stress was immobilization for 4 weeks, every other day. The brain was removed after this period and each brain divided into two parts in a coronal section manner. Anterior part used for histological studies with H&E staining and posterior part used for measurement of NO production using spectrophotometer at 540 nm wavelengh. Results: Statistical analysis of microscopic and light microscopic finding showed that thickness of prefrontal cortex and NO production were significantly decreased in stressed rats and especially in groups which received 7- nitroindazole and L-NAME and L-arginine could reverse these results. Discussion: According to this research, we could say that L-arginine decreases the cortical damages in stressed rats and 7-nitroindazole and L-NAME increase this damage in non-stressed group. Although in non stressed groups, L-arginine, L-NAME and 7- nitroindazole were all non-protective and damaging.

  10. The effect of L-Arginine on the brain tissue of stressed rats

    Directory of Open Access Journals (Sweden)

    Batoul Ebadi

    2010-01-01

    Full Text Available   Abstract  Introduction: This study was conducted to determine the possible beneficial results of L-arginine on prefrontal cortex of rats which impressed by immobilization stress to define the synchronous impression of stress and nitric oxide (NO on evolution of prefrontal cortex of rats after birth. Methods: Forty-eight one month, male Wistar rats were divided into two groups: stressed and non-stressed. L-Arginine (200 mg/kg as a NO synthase (NOS inducer and L-NAME (2O mg/kg were injected intraperitonealy (IP and 7- nitroindazde (25 mg/kg as non-specific was injected subcutaneously (S.C. for 4 weeks. The kind of stress was immobilization for 4 weeks, every other day. The brain was removed after this period and each brain divided into two parts in a coronal section manner. Anterior part used for histological studies with H&E staining and posterior part used for measurement of NO production using spectrophotometer at 540 nm wavelengh. Results: Statistical analysis of microscopic and light microscopic finding showed that thickness of prefrontal cortex and NO production were significantly decreased in stressed rats and especially in groups which received 7- nitroindazole and L-NAME and L-arginine could reverse these results. Discussion: According to this research, we could say that L-arginine decreases the cortical damages in stressed rats and 7-nitroindazole and L-NAME increase this damage in non-stressed group. Although in non stressed groups, L-arginine, L-NAME and 7- nitroindazole were all non-protective and damaging.

  11. EFFECTS OF ARGININE AND VITAMIN E SUPPLEMENTED DIETS ON THE IMMUNOLOGICAL RESPONSE OF BROILERS CHICKENS

    Directory of Open Access Journals (Sweden)

    David Jesús Chan Diaz

    2012-08-01

    Full Text Available In order to evaluate the effect of arginine and vitamin E supplementation in broiler chicken diets on the immune response during post-vaccine stress, a trial was conducted with 700 chicks (1 day-old which were distributed into 28 floor-pens and fed one of four dietary treatments (with 7 replicates randomly assigned: T1 = control diet (1.31 % of arginine and 10 IU of vitamin E/kg of feed; T2 = T1 + 0.3 % of arginine; T3 = T1 + 70 IU of vitamin E; T4 = T1 + 0.3 % of arginine + 70 IU of vitamin E. At 12 days of age, all birds were vaccinated against Newcastle disease virus (ND, infectious bronchitis, avian influenza (AI and fowl pox. The traits evaluated were: post-vaccine reaction at days 14, 16, 18, 21 and 23; antibody titers against ND and AI, and relative lymphoid organs weight at days 11, 19 and 26; and the performance were recorded weekly. Chickens fed T2, T4 (at day 16, and T3 (at day 21 had lesser (p≤0.05 post-vaccine reaction than birds fed T1. The antibody titers against ND (at day 11 was higher (p≤0.05 in chickens fed T4 (3.1, T3 (2.7 and T2 (2.7 compared to T1 (1.6; meanwhile, for AI titers no differences were found. There were no differences, neither for immune organs weight, nor for performance. In conclusion, arginine and vitamin E supplementation in broiler chicken diets reduced the post-vaccine stress and improved the immune response without affecting the performance.

  12. Endothelial arginine resynthesis contributes to the maintenance of vasomotor function in male diabetic mice.

    Directory of Open Access Journals (Sweden)

    Ramesh Chennupati

    Full Text Available Argininosuccinate synthetase (ASS is essential for recycling L-citrulline, the by-product of NO synthase (NOS, to the NOS substrate L-arginine. Here, we assessed whether disturbed arginine resynthesis modulates endothelium-dependent vasodilatation in normal and diabetic male mice.Endothelium-selective Ass-deficient mice (Assfl/fl/Tie2Cretg/- = Ass-KOTie2 were generated by crossing Assfl/fl mice ( = control with Tie2Cre mice. Gene ablation in endothelial cells was confirmed by immunohistochemistry. Blood pressure (MAP was recorded in 34-week-old male mice. Vasomotor responses were studied in isolated saphenous arteries of 12- and 34-week-old Ass-KOTie2 and control animals. At the age of 10 weeks, diabetes was induced in control and Ass-KOTie2 mice by streptozotocin injections. Vasomotor responses of diabetic animals were studied 10 weeks later. MAP was similar in control and Ass-KOTie2 mice. Depletion of circulating L-arginine by arginase 1 infusion or inhibition of NOS activity with L-NAME resulted in an increased MAP (10 and 30 mmHg, respectively in control and Ass-KOTie2 mice. Optimal arterial diameter, contractile responses to phenylephrine, and relaxing responses to acetylcholine and sodium nitroprusside were similar in healthy control and Ass-KOTie2 mice. However, in diabetic Ass-KOTie2 mice, relaxation responses to acetylcholine and endothelium-derived NO (EDNO were significantly reduced when compared to diabetic control mice.Absence of endothelial citrulline recycling to arginine did not affect blood pressure and systemic arterial vasomotor responses in healthy mice. EDNO-mediated vasodilatation was significantly more impaired in diabetic Ass-KOTie2 than in control mice demonstrating that endothelial arginine recycling becomes a limiting endothelial function in diabetes.

  13. Transcriptome analysis shows activation of the arginine deiminase pathway in Lactococcus lactis as a response to ethanol stress.

    Science.gov (United States)

    Díez, Lorena; Solopova, Ana; Fernández-Pérez, Rocío; González, Miriam; Tenorio, Carmen; Kuipers, Oscar P; Ruiz-Larrea, Fernanda

    2017-09-18

    This paper describes the molecular response of Lactococcus lactis NZ9700 to ethanol. This strain is a well-known nisin producer and a lactic acid bacteria (LAB) model strain. Global transcriptome profiling using DNA microarrays demonstrated a bacterial adaptive response to the presence of 2% ethanol in the culture broth and differential expression of 67 genes. The highest up-regulation was detected for those genes involved in arginine degradation through the arginine deiminase (ADI) pathway (20-40 fold up-regulation). The metabolic responses to ethanol of wild type L. lactis strains were studied and compared to those of regulator-deletion mutants MG∆argR and MG∆ahrC. The results showed that in the presence of 2% ethanol those strains with an active ADI pathway reached higher growth rates when arginine was available in the culture broth than in absence of arginine. In a chemically defined medium strains with an active ADI pathway consumed arginine and produced ornithine in the presence of 2% ethanol, hence corroborating that arginine catabolism is involved in the bacterial response to ethanol. This is the first study of the L. lactis response to ethanol stress to demonstrate the relevance of arginine catabolism for bacterial adaptation and survival in an ethanol containing medium. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Preliminary characterization of residual biomass from Hibiscus ...

    African Journals Online (AJOL)

    Hibiscus sabdariffa calyces are mainly used for different agro-food and beverages applications. The residual biomass generated contains various useful substances that were extracted and characterized. It contained 23% (w/w) soluble pectic material, a food additive, extracted with hot acidified water (80°C, pH = 1.5) and ...

  15. Determination of agmatine using isotope dilution UPLC-tandem mass spectrometry: application to the characterization of the arginine decarboxylase pathway in Pseudomonas aeruginosa.

    Science.gov (United States)

    Dalluge, Joseph J; McCurtain, Jennifer L; Gilbertsen, Adam J; Kalstabakken, Kyle A; Williams, Bryan J

    2015-07-01

    A method has been developed for the direct determination of agmatine in bacterial culture supernatants using isotope dilution ultra performance liquid chromatography (UPLC)-tandem mass spectrometry (UPLC-MS/MS). Agmatine determination in bacterial supernatants is comprised of spiking culture or isolate supernatants with a fixed concentration of uniformly labeled (13)C5,(15)N4-agmatine (synthesized by decarboxylation of uniformly labeled (13)C6,(15)N4-arginine using arginine decarboxylase from Pseudomonas aeruginosa) as an internal standard, followed by derivatization with 4-fluoro-7-nitro-2,1,3-benzoxadiazole (NBDF) to improve the reversed-phase chromatographic retention characteristics of agmatine, as well as the selectivity and sensitivity of UPLC-MS/MS detection of this amine in complex biologically derived mixtures. Intrasample precisions for measurement of agmatine in culture supernatants average 4.1% (relative standard deviation). Calibration curves are linear over the range 5 nM to 10 μM, and the detection limit is estimated at 1.5 nM. To demonstrate the utility of the method, agmatine levels in supernatants of overnight cultures of wild-type (UCBPP-PA14), as well as arginine decarboxylase and agmatine deiminase mutant strains of P. aeruginosa strain UCBPP-PA14 were measured. This method verified that the mutant strains are lacking the specific metabolic capabilities to produce and metabolize agmatine. In addition, measurement of agmatine in supernatants of a panel of clinical isolates from patients with cystic fibrosis revealed that three of the P. aeruginosa isolates hyper-secreted agmatine into the supernatant, hypothesized to be a result of a mutation in the aguA gene. Because agmatine has potential inflammatory activities in the lung, this phenotype may be a virulence factor for P. aeruginosa in the lung environment of cystic fibrosis patients.

  16. Determination of agmatine using isotope dilution UPLC-tandem mass spectrometry: application to the characterization of the arginine decarboxylase pathway in Pseudomonas aeruginosa

    Science.gov (United States)

    McCurtain, Jennifer L.; Gilbertsen, Adam J.; Kalstabakken, Kyle A.; Williams, Bryan J.

    2018-01-01

    A method has been developed for the direct determination of agmatine in bacterial culture supernatants using isotope dilution ultra performance liquid chromatography (UPLC)-tandem mass spectrometry (UPLC-MS/MS). Agmatine determination in bacterial supernatants is comprised of spiking culture or isolate supernatants with a fixed concentration of uniformly labeled 13C5,15N4-agmatine (synthesized by decarboxylation of uniformly labeled 13C6,15N4-arginine using arginine decarboxylase from Pseudomonas aeruginosa) as an internal standard, followed by derivatization with 4-fluoro-7-nitro-2,l,3-benzoxadiazole (NBDF) to improve the reversed-phase chromatographic retention characteristics of agmatine, as well as the selectivity and sensitivity of UPLC-MS/MS detection of this amine in complex biologically derived mixtures. Intrasample precisions for measurement of agmatine in culture supernatants average 4.1 % (relative standard deviation). Calibration curves are linear over the range 5 nM to 10 μM, and the detection limit is estimated at 1.5 nM. To demonstrate the utility of the method, agmatine levels in supernatants of overnight cultures of wild-type (UCBPP-PA14), as well as arginine decarboxylase and agmatine deiminase mutant strains of P. aeruginosa strain UCBPP-PA14 were measured. This method verified that the mutant strains are lacking the specific metabolic capabilities to produce and metabolize agmatine. In addition, measurement of agmatine in supernatants of a panel of clinical isolates from patients with cystic fibrosis revealed that three of the P. aeruginosa isolates hyper-secreted agmatine into the supernatant, hypothesized to be a result of a mutation in the aguA gene. Because agmatine has potential inflammatory activities in the lung, this phenotype may be a virulence factor for P. aeruginosa in the lung environment of cystic fibrosis patients. PMID:25957842

  17. Class side effects: decreased pressure in the lower oesophageal and the pyloric sphincters after the administration of dopamine antagonists, neuroleptics, anti-emetics, L-NAME, pentadecapeptide BPC 157 and L-arginine.

    Science.gov (United States)

    Belosic Halle, Zeljka; Vlainic, Josipa; Drmic, Domagoj; Strinic, Dean; Luetic, Kresimir; Sucic, Mario; Medvidovic-Grubisic, Maria; Pavelic Turudic, Tatjana; Petrovic, Igor; Seiwerth, Sven; Sikiric, Predrag

    2017-05-17

    The ulcerogenic potential of dopamine antagonists and L-NAME in rats provides unresolved issues of anti-emetic neuroleptic application in both patients and experimental studies. Therefore, in a 1-week study, we examined the pressures within the lower oesophageal and the pyloric sphincters in rats [assessed manometrically (cm H 2 O)] after dopamine neuroleptics/prokinetics, L-NAME, L-arginine and stable gastric pentadecapeptide BPC 157 were administered alone and/or in combination. Medication (/kg) was given once daily intraperitoneally throughout the 7 days, with the last dose at 24 h before pressure assessment. Given as individual agents to healthy rats, all dopamine antagonists (central [haloperidol (6.25 mg, 16 mg, 25 mg), fluphenazine (5 mg), levomepromazine (50 mg), chlorpromazine (10 mg), quetiapine (10 mg), olanzapine (5 mg), clozapine (100 mg), sulpiride (160 mg), metoclopramide (25 mg)) and peripheral(domperidone (10 mg)], L-NAME (5 mg) and L-arginine (100 mg) decreased the pressure within both sphincters. As a common effect, this decreased pressure was rescued, dose-dependently, by BPC 157 (10 µg, 10 ng) (also note that L-arginine and L-NAME given together antagonized each other's responses). With haloperidol, L-NAME worsened both the lower oesophageal and the pyloric sphincter pressure, while L-arginine ameliorated lower oesophageal sphincter but not pyloric sphincter pressure, and antagonized L-NAME effect. With domperidone, L-arginine originally had no effect, while L-NAME worsened pyloric sphincter pressure. This effect was opposed by L-arginine. All these effects were further reversed towards a stronger beneficial effect, close to normal pressure values, by the addition of BPC 157. In addition, NO level was determined in plasma, sphincters and brain tissue. Thiobarbituric acid reactive substances (TBARS) were also assessed. Haloperidol increased NO levels (in both sphincters, the plasma and brain), consistently producing increased

  18. Evaluation of residue-residue contact predictions in CASP9

    KAUST Repository

    Monastyrskyy, Bohdan; Fidelis, Krzysztof; Tramontano, Anna; Kryshtafovych, Andriy

    2011-01-01

    This work presents the results of the assessment of the intramolecular residue-residue contact predictions submitted to CASP9. The methodology for the assessment does not differ from that used in previous CASPs, with two basic evaluation measures

  19. Sharing Residual Liability

    DEFF Research Database (Denmark)

    Carbonara, Emanuela; Guerra, Alice; Parisi, Francesco

    2016-01-01

    Economic models of tort law evaluate the efficiency of liability rules in terms of care and activity levels. A liability regime is optimal when it creates incentives to maximize the value of risky activities net of accident and precaution costs. The allocation of primary and residual liability...... for policy makers and courts in awarding damages in a large number of real-world accident cases....

  20. The Hydrophobic Region of the DmsA Twin-Arginine Leader Peptide Determines Specificity with Chaperone DmsD

    OpenAIRE

    Winstone, Tara M. L.; Tran, Vy A.; Turner, Raymond J.

    2013-01-01

    The system specific chaperone DmsD plays a role in the maturation of the catalytic subunit of dimethyl sulfoxide (DMSO) reductase, DmsA. Pre-DmsA contains a 45-amino acid twin-arginine leader peptide that is important for targeting and translocation of folded and cofactor-loaded DmsA by the twin-arginine translocase. DmsD has previously been shown to interact with the complete twin-arginine leader peptide of DmsA. In this study, isothermal titration calorimetry was used to investigate the the...

  1. Arginine kinase in Toxocara canis: Exon-intron organization, functional analysis of site-directed mutants and evaluation of putative enzyme inhibitors.

    Science.gov (United States)

    Wickramasinghe, Susiji; Yatawara, Lalani; Nagataki, Mitsuru; Agatsuma, Takeshi

    2016-10-01

    To determine exon/intron organization of the Toxocara canis (T. canis) AK (TCAK) and to test green and black tea and several other chemicals against the activity of recombinant TCAK in the guanidino-specific region by site-directed mutants. Amplification of genomic DNA fragments containing introns was carried out by PCRs. The open-reading frame (1200 bp) of TCAK (wild type) was cloned into the BamH1/SalI site of pMAL-c2X. The maltose-binding protein-TCAK fusion protein was expressed in Escherichia coli TB1 cells. The purity of the expressed enzyme was verified by SDS-PAGE. Mutations were introduced into the guanidino-specific region and other areas of pMAL/TCAK by PCR. Enzyme activity was measured with an NADH-linked assay at 25 °C for the forward reaction (phosphagen synthesis). Arginine kinase in T. canis has a seven-exon/six-intron gene structure. The lengths of the introns ranged from 542 bp to 2 500 bp. All introns begin with gt and end with ag. Furthermore, we measured the enzyme activity of site-directed mutants of the recombinant TCAK. The K m value of the mutant (Alanine to Serine) decreased indicating a higher affinity for substrate arginine than the wild-type. The K m value of the mutant (Serine to Glycine) increased to 0.19 mM. The K m value (0.19 mM) of the double mutant (Alanine-Serine to Serine-Glycine) was slightly greater than in the wild-type (0.12 mM). In addition, several other chemicals were tested; including plant extract Azadiracta indica (A. indica), an aminoglycoside antibiotic (aminosidine), a citrus flavonoid glycoside (rutin) and a commercially available catechin mixture against TCAK. Green and black tea (1:10 dilution) produced 15% and 25% inhibition of TCAK, respectively. The extract of A. indica produced 5% inhibition of TCAK. Moreover, green and black tea produced a non-competitive type of inhibition and A. indica produced a mixed-type of inhibition on TCAK. Arginine kinase in T. canis has a seven-exon/six-intron gene

  2. The Histological Effects of L-arginine on Ventricular Myocardium in Iron Treated Male Rats

    Directory of Open Access Journals (Sweden)

    M Sofiabadi

    2012-05-01

    Full Text Available

    Background and Objectives: Iron overload is detrimental for the body and can create damage to different body tissues, such as myocardium by producing oxidative stress. Therefore, the antioxidant factors can neutralize iron induced damages. According to available reports, L-arginine as a precursor nitric oxide production has antioxidant effects. This study was carried out to evaluate the histological effects of iron overload on ventricular muscle and preventive role of L-arginine in male rats.
    Methods: In this experiment, 40 male rats with weight range of 300-250g were divided at random into five equal groups including:1- Control, 2- Iron (10mg/kg, ip, 3- Iron(10mg/kg, ip+L-arginine (1mg/ml, po, 4- Iron (50mg/kg, ip and 5- Iron (50mg/kg,ip+L-arginine(1mg/ml,po. After treatment (6 weeks, the animals were anesthetized and the samples of left apical ventricular myocardium were taken out and morphological studies were done following fixation with 10% formalin and H&E staining. Microscopic parameters under study were cell swelling, vessel dilatation and hypercongestion, cell necrosis and tissue deformity. The type and severity of damage to the tissue were also noted. Data were analyzed using chi-square statistical procedure, and Pvalue≤0.05 were considered to be significant. 
    Results: The data showed moderate changes in the ventricular myocardium of group 2 that was significant in comparison to the control group (P<0.05. The ventricular myocardium of group 3 showed low changes and wasn't significant in comparison to control group (P=0.84. The ventricular myocardium of the group 4 showed severe changes in comparison to the control group (P<0.01. The low change showed in the ventricular myocardium of group 5 that wasn't significant in comparison to the control group.

    Conclusion: This study showed

  3. Staphylococcal nuclease active-site amino acids: pH dependence of tyrosines and arginines by 13C NMR and correlation with kinetic studies

    International Nuclear Information System (INIS)

    Grissom, C.G.; Markley, J.L.

    1989-01-01

    The pH and temperature dependence of the kinetic parameters of staphylococcal nuclease have been examined with three p-nitrophenyl phosphate containing DNA analogues that vary as to 3'-substituent. With wild-type (Foggi variant) nuclease (nuclease wt) and the substrates thymidine 3'-phosphate 5'-(p-nitrophenyl phosphate) (PNPdTp), thymidine 3'-methylphosphonate 5'-(p-nitrophenyl phosphate) (PNPdTp Me), and thymidine 5'-(p-nitrophenyl phosphate) (PNPdT), k cat remains nearly constant at 13 min -1 . However, k cat /k m with nuclease wt varies considerably. The data suggests that the inflection k cat /K m with pK a at 9.67 arises from ionization of tyrosine-85, which hydrogen bonds to the divalent 3'-phosphomonester of substrates with this substituent. The enthalpy of ionization of both deprotonation steps in the k cat /K m versus pH profile is 5 kcal/mol. 13 C NMR has been used to determine the pK a values of the arginine and tyrosine residues. The results do not rule out arginine as a candidate for the acidic catalyst that protonates the 5'-ribose alkoxide prior to product release. The phenolic hydroxyl carbon of tyrosine-85 has been assigned by comparing the 13 C NMR spectrum of nuclease wt and nuclease Y85F. This correlation between pK a values along with the absence of other candidates indicates that the ionization of tyrosine-85 is the pK a seen in the k cat /K m vs pH profile for substrates with a divalent 3'-phosphomonester. This conclusion is consistent with the proposed role of tyrosine-85 as a hydrogen-bond donor to the 3'-phosphomonoester of substrates poised for exonucleolytic hydrolysis

  4. Identification of a Novel Protein Arginine Methyltransferase 5 Inhibitor in Non-small Cell Lung Cancer by Structure-Based Virtual Screening

    Directory of Open Access Journals (Sweden)

    Qianqian Wang

    2018-03-01

    Full Text Available Protein arginine methyltransferase 5 (PRMT5 is able to regulate gene transcription by catalyzing the symmetrical dimethylation of arginine residue of histone, which plays a key role in tumorigenesis. Many efforts have been taken in discovering small-molecular inhibitors against PRMT5, but very few were reported and most of them were SAM-competitive. EPZ015666 is a recently reported PRMT5 inhibitor with a new binding site, which is different from S-adenosylmethionine (SAM-binding pocket. This new binding site provides a new clue for the design and discovery of potent and specific PRMT5 inhibitors. In this study, the structure-based virtual screening targeting this site was firstly performed to identify potential PRMT5 inhibitors. Then, the bioactivity of the candidate compound was studied. MTT results showed that compound T1551 decreased cell viability of A549 and H460 non-small cell lung cancer cell lines. By inhibiting the methyltransferase activity of PRMT5, T1551 reduced the global level of H4R3 symmetric dimethylation (H4R3me2s. T1551 also downregulated the expression of oncogene FGFR3 and eIF4E, and disturbed the activation of related PI3K/AKT/mTOR and ERK signaling in A549 cell. Finally, we investigated the conformational spaces and identified collective motions important for description of T1551/PRMT5 complex by using molecular dynamics simulation and normal mode analysis methods. This study provides a novel non-SAM-competitive hit compound for developing small molecules targeting PRMT5 in non-small cell lung cancer.

  5. Cooperativity in the two-domain arginine kinase from the sea anemone Anthopleura japonicus. II. Evidence from site-directed mutagenesis studies.

    Science.gov (United States)

    Tada, Hiroshi; Suzuki, Tomohiko

    2010-08-01

    The arginine kinase (AK) from the sea anemone Anthopleura japonicus has an unusual two-domain structure (contiguous dimer; denoted by D1-D2). In a previous report, we suggested cooperativity in the contiguous dimer, which may be a result of domain-domain interactions, using MBP-fused enzymes. To further understand this observation, we inserted six-Lys residues into the linker region of the two-domain AK (D1-K6-D2 mutant) using His-tagged enzyme. The dissociation constants, K(a) and K(ia), of the mutant were similar to those of the wild-type enzyme but the catalytic constant, k(cat), was decreased to 28% that of the wild-type, indicating that some of the domain-domain interactions are lost due to the six-Lys insertion. Y68 plays a major role in arginine binding in the catalytic pocket in Limulus AK, and introduction of mutation at the Y68 position virtually abolishes catalytic activity. Thus, the constructed D1(Y68G)-D2 and D1-D2(Y68G) mutants mimic the D1(inactive)-D2(active) and D1(active)-D2(inactive) enzymes, respectively. The k(cat) values of both Y68 mutants were decreased to 13-18% that of the wild-type enzyme, which is much less than the 50% level of the two-domain enzyme. Thus, it is clear that substrate-binding to both domains is necessary for full expression of activity. In other words, substrate-binding appears to act as the trigger of the functional cooperativity in two-domain AK. Copyright 2010 Elsevier B.V. All rights reserved.

  6. Upgraded wood residue fuels 1995

    International Nuclear Information System (INIS)

    Vinterbaeck, J.

    1995-01-01

    The Swedish market for upgraded residue fuels, i.e. briquettes, pellets and wood powder, has developed considerably during the nineties. The additional costs for the upgrading processes are regained and create a surplus in other parts of the system, e.g. in the form of higher combustion efficiencies, lower investment costs for burning equipment, lower operation costs and a diminished environmental impact. All these factors put together have resulted in a rapid growth of this part of the energy sector. In 1994 the production was 1.9 TWh, an increase of 37 % compared to the previous year. In the forthcoming heating season 1995/96 the production may reach 4 TWh. 57 refs, 11 figs, 6 tabs

  7. Optimization of the Use of Selected Non-Phosphate Water Retention Additives in Minced Beef Using Response Surface Methodology

    Science.gov (United States)

    Shang, Xiaolan; Qiao, Jie; Liu, Yujie

    2017-12-01

    This study looked to determine what the optimum cooking loss for minced beef was when three different non-phosphate water retention additives (L-Arginine, sodium carbonate, and sodium citrate) were combined; the optimum value was determined using a Box-Behnken response surface design method. The optimum value was found to be 8.26%, and it was obtained when 0.29% L-Arginine, 0.45% sodium carbonate, and 0.24% sodium citrate were added to the beef.

  8. Nitrous oxide emission from soils amended with crop residues

    NARCIS (Netherlands)

    Velthof, G.L.; Kuikman, P.J.; Oenema, O.

    2002-01-01

    Crop residues incorporated in soil are a potentially important source of nitrous oxide (N2O), though poorly quantified. Here, we report on the N2O emission from 10 crop residues added to a sandy and a clay soil, both with and without additional nitrate (NO3-). In the sandy soil, total nitrous oxide

  9. Machine for compacting solid residues

    International Nuclear Information System (INIS)

    Herzog, J.

    1981-11-01

    Machine for compacting solid residues, particularly bulky radioactive residues, constituted of a horizontally actuated punch and a fixed compression anvil, in which the residues are first compacted horizontally and then vertically. Its salient characteristic is that the punch and the compression anvil have embossments on the compression side and interpenetrating plates in the compression position [fr

  10. Residual Defect Density in Random Disks Deposits.

    Science.gov (United States)

    Topic, Nikola; Pöschel, Thorsten; Gallas, Jason A C

    2015-08-03

    We investigate the residual distribution of structural defects in very tall packings of disks deposited randomly in large channels. By performing simulations involving the sedimentation of up to 50 × 10(9) particles we find all deposits to consistently show a non-zero residual density of defects obeying a characteristic power-law as a function of the channel width. This remarkable finding corrects the widespread belief that the density of defects should vanish algebraically with growing height. A non-zero residual density of defects implies a type of long-range spatial order in the packing, as opposed to only local ordering. In addition, we find deposits of particles to involve considerably less randomness than generally presumed.

  11. Quadratic residues and non-residues selected topics

    CERN Document Server

    Wright, Steve

    2016-01-01

    This book offers an account of the classical theory of quadratic residues and non-residues with the goal of using that theory as a lens through which to view the development of some of the fundamental methods employed in modern elementary, algebraic, and analytic number theory. The first three chapters present some basic facts and the history of quadratic residues and non-residues and discuss various proofs of the Law of Quadratic Reciprosity in depth, with an emphasis on the six proofs that Gauss published. The remaining seven chapters explore some interesting applications of the Law of Quadratic Reciprocity, prove some results concerning the distribution and arithmetic structure of quadratic residues and non-residues, provide a detailed proof of Dirichlet’s Class-Number Formula, and discuss the question of whether quadratic residues are randomly distributed. The text is a valuable resource for graduate and advanced undergraduate students as well as for mathematicians interested in number theory.

  12. How does spa treatment affect cardiovascular function and vascular endothelium in patients with generalized osteoarthritis? A pilot study through plasma asymmetric di-methyl arginine (ADMA) and L-arginine/ADMA ratio

    Science.gov (United States)

    Karaarslan, Fatih; Ozkuk, Kagan; Seringec Karabulut, Serap; Bekpinar, Seldag; Karagulle, Mufit Zeki; Erdogan, Nergis

    2018-05-01

    The study aims to investigate the effect of spa treatment on vascular endothelium and clinical symptoms of generalized osteoarthritis. Forty generalized osteoarthritis (GOA) patients referred to a government spa hospital, and 40 GOA patients followed on university hospital locomotor system disease ambulatory clinics were included as study and control groups, respectively. Study group received spa treatment including thermal water baths, physical therapy modalities, and exercises. Control group was followed with home exercises for 15 days. Plasma ADMA, L-arginine, L-arginine/ADMA ratio, routine blood analyses, 6-min walking test, including fingertip O2 saturation, systolic/diastolic blood pressure, and pulse rate, were measured at the beginning and at the end of treatment. Groups were evaluated with VAS pain, patient, and physician global assessment; HAQ; and WOMAC at the beginning, at the end, and after 1 month of treatment. In study group, L-arginine and L-arginine/ADMA ratio showed statistically significant increase after treatment. Plasma ADMA levels did not change. There is no significant difference in intergroup comparison. Study group displayed statistically significant improvements in all clinical parameters. The study showed that spa treatment does not cause any harm to the vascular endothelium through ADMA. Significant increase in plasma L-arginine and L-arginine/ADMA ratio suggests that balneotherapy may play a preventive role on cardiovascular diseases. Balneotherapy provides meaningful improvements on clinical parameters of GOA.

  13. How does spa treatment affect cardiovascular function and vascular endothelium in patients with generalized osteoarthritis? A pilot study through plasma asymmetric di-methyl arginine (ADMA) and L-arginine/ADMA ratio

    Science.gov (United States)

    Karaarslan, Fatih; Ozkuk, Kagan; Seringec Karabulut, Serap; Bekpinar, Seldag; Karagulle, Mufit Zeki; Erdogan, Nergis

    2017-12-01

    The study aims to investigate the effect of spa treatment on vascular endothelium and clinical symptoms of generalized osteoarthritis. Forty generalized osteoarthritis (GOA) patients referred to a government spa hospital, and 40 GOA patients followed on university hospital locomotor system disease ambulatory clinics were included as study and control groups, respectively. Study group received spa treatment including thermal water baths, physical therapy modalities, and exercises. Control group was followed with home exercises for 15 days. Plasma ADMA, L-arginine, L-arginine/ADMA ratio, routine blood analyses, 6-min walking test, including fingertip O2 saturation, systolic/diastolic blood pressure, and pulse rate, were measured at the beginning and at the end of treatment. Groups were evaluated with VAS pain, patient, and physician global assessment; HAQ; and WOMAC at the beginning, at the end, and after 1 month of treatment. In study group, L-arginine and L-arginine/ADMA ratio showed statistically significant increase after treatment. Plasma ADMA levels did not change. There is no significant difference in intergroup comparison. Study group displayed statistically significant improvements in all clinical parameters. The study showed that spa treatment does not cause any harm to the vascular endothelium through ADMA. Significant increase in plasma L-arginine and L-arginine/ADMA ratio suggests that balneotherapy may play a preventive role on cardiovascular diseases. Balneotherapy provides meaningful improvements on clinical parameters of GOA.

  14. Exogenous L-arginine reduces matrix metalloproteinase-2 and -9 activities and oxidative stress in patients with hypertension

    DEFF Research Database (Denmark)

    Garcia, Vinicius P; Rocha, Helena N M; Silva, Gustavo M.

    2016-01-01

    Aims Increased matrix metalloproteinases activity and reduced nitric oxide (NO) bioavailability contributes to development of hypertension and this may be associated with a defective L-arginine-NO pathway. Exogenous L-arginine improves endothelial function to prevent the onset of cardiovascular...... disease, but the mechanism by which this is accomplished remains unclear. We determined the effects of exogenous L-arginine infusion on vascular biomarkers in patients with hypertension. Main methods Venous blood samples were obtained from seven patients with hypertension (45 ± 5 yrs., HT group...... biomarkers between groups during the saline infusion (P > 0.05). Significance Exogenous L-arginine diminished metalloproteinase-2 and -9 activities and MMP-9/TIMP-1 ratio along with restoring the oxidative stress balance in patients with hypertension....

  15. Mobility of organic carbon from incineration residues

    International Nuclear Information System (INIS)

    Ecke, Holger; Svensson, Malin

    2008-01-01

    Dissolved organic carbon (DOC) may affect the transport of pollutants from incineration residues when landfilled or used in geotechnical construction. The leaching of dissolved organic carbon (DOC) from municipal solid waste incineration (MSWI) bottom ash and air pollution control residue (APC) from the incineration of waste wood was investigated. Factors affecting the mobility of DOC were studied in a reduced 2 6-1 experimental design. Controlled factors were treatment with ultrasonic radiation, full carbonation (addition of CO 2 until the pH was stable for 2.5 h), liquid-to-solid (L/S) ratio, pH, leaching temperature and time. Full carbonation, pH and the L/S ratio were the main factors controlling the mobility of DOC in the bottom ash. Approximately 60 weight-% of the total organic carbon (TOC) in the bottom ash was available for leaching in aqueous solutions. The L/S ratio and pH mainly controlled the mobilization of DOC from the APC residue. About 93 weight-% of TOC in the APC residue was, however, not mobilized at all, which might be due to a high content of elemental carbon. Using the European standard EN 13 137 for determination of total organic carbon (TOC) in MSWI residues is inappropriate. The results might be biased due to elemental carbon. It is recommended to develop a TOC method distinguishing between organic and elemental carbon

  16. Self-assembled nanoparticles based on amphiphilic chitosan derivative and arginine for oral curcumin delivery

    Directory of Open Access Journals (Sweden)

    Raja MA

    2016-09-01

    Full Text Available Mazhar Ali Raja, Shah Zeenat, Muhammad Arif, Chenguang Liu College of Marine Life Science, Ocean University of China, Qingdao, Shandong, People’s Republic of China Abstract: Curcumin (Cur is a striking anticancer agent, but its low aqueous solubility, poor absorption, hasty metabolism, and elimination limit its oral bioavailability and consequently hinder its development as a drug. To redress these limitations, amphiphilic chitosan (CS conjugate with improved mucoadhesion and solubility over a wider pH range was developed by modification with hydrophobic acrylonitrile (AN and hydrophilic arginine (Arg; the synthesized conjugate (AN–CS–Arg, which was well characterized by Fourier transform infrared and 1H nuclear magnetic resonance spectroscopy. Results of critical aggregation concentration revealed that the AN–CS–Arg conjugate had low critical aggregation concentration and was prone to form self-assembled nanoparticles (NPs in aqueous medium. Cur-encapsulated AN–CS–Arg NPs (AN–CS–Arg/Cur NPs were developed by a simple sonication method and characterized for the physicochemical parameters such as zeta potential, particle size, and drug encapsulation. The results showed that zeta potential of the prepared NPs was 40.1±2.81 mV and the average size was ~218 nm. A considerable improvement in the aqueous solubility of Cur was observed after encapsulation into AN–CS–Arg/Cur NPs. With the increase in Cur concentration, loading efficiency increased but encapsulation efficiency decreased. The in vitro release profile exhibited sustained release pattern from the AN–CS–Arg/Cur NPs in typical biological buffers. The ex vivo mucoadhesion study revealed that AN–CS–Arg/Cur NPs had greater mucoadhesion than the control CS NPs. Compared with free Cur solution, AN–CS–Arg/Cur NPs showed stronger dose-dependent cytotoxicity against HT-29 cells. In addition, it was observed that cell uptake of AN–CS–Arg/Cur NPs was much higher

  17. Neuropsychological profile and clinical effects of arginine treatment in children with creatine transport deficiency

    Science.gov (United States)

    2012-01-01

    Background SLC6A8, an X-linked gene, encodes the creatine transporter (CRTR) and its mutations lead to cerebral creatine (Cr) deficiency which results in mental retardation, speech and language delay, autistic-like behaviour and epilepsy (CRTR-D, OMIM 300352). CRTR-D represents the most frequent Cr metabolism disorder but, differently from Cr synthesis defects, that are partially reversible by oral Cr supplementation, does not respond to Cr treatment even if precociously administrated. The precursors of Cr are the non-essential amino acids Glycine (Gly) and Arginine (Arg), which have their own transporters at the brain–blood barrier level and, therefore, their supplementation appears an attractive and feasible therapeutic option aimed at stimulating Cr endogenous synthesis and, in this way, at overcoming the block of Cr transport within the brain. However, until now the effects of Arg and/or Gly supplementation on Cr brain levels and behaviour have been controversial. Methods In this study five Italian male patients affected by CRTR-D were supplemented with oral L-Arg at a dosage of 300 mg/kg/day divided into 3 doses, for 24–36 months. Biochemical and plasmatic amino acids examinations and thyroid hormone dosages were periodically performed. Moreover, Proton and Phosphorus Magnetic Resonance Spectroscopy (MRS) was monitored during follow-up in concurrence with neuropsychological evaluations. Results During L-Arg treatment a clinical improvement in motor skills and to a lesser extent in communication and attention was observed. In addition, all patients had a reduction in the number and frequency of epileptic seizures. Daily living skills appeared also to be positively influenced by L-Arg treatment. Moreover, Total Cr and especially PhosphoCr, evaluated by proton and phosphorus spectroscopy, showed a mild increase, although well below the normal range. Conclusion This study provides information to support the effectiveness of L-Arg supplement treatment in

  18. Selective small-chemical inhibitors of protein arginine methyltransferase 5 with anti-lung cancer activity.

    Directory of Open Access Journals (Sweden)

    Gui-Mei Kong

    Full Text Available Protein arginine methyltransferase 5 (PRMT5 plays critical roles in a wide variety of biological processes, including tumorigenesis. By screening a library of small chemical compounds, we identified eight compounds that selectively inhibit the PRMT5 enzymatic activity, with IC50 values ranging from 0.1 to 6 μM. Molecular docking simulation and site-directed mutagenesis indicated that identified compounds target the substrate-binding site in PRMT5. Treatment of lung cancer cells with identified inhibitors led to inhibition of the symmetrical arginine methylation of SmD3 and histones and the cellular proliferation. Oral administration of the inhibitor demonstrated antitumor activity in a lung tumor xenograft model. Thus, identified PRMT5-specific small-molecule inhibitors would help elucidate the biological roles of PRMT5 and serve as lead compounds for future drug development.

  19. Solid-state properties and dissolution behaviour of tablets containing co-amorphous indomethacin-arginine

    DEFF Research Database (Denmark)

    Lenz, Elisabeth; Jensen, Katrine Birgitte Tarp; Blaabjerg, Lasse Ingerslev

    2015-01-01

    arginine in a larger production scale. In this work, a tablet formulation was developed for a co-amorphous salt, namely spray dried indomethacin–arginine (SD IND–ARG). The effects of compaction pressure on tablet properties, physical stability and dissolution profiles under non-sink conditions were examined....... Dissolution profiles of tablets with SD IND–ARG (TAB SD IND–ARG) were compared to those of tablets containing a physical mixture of crystalline IND and ARG (TAB PM IND–ARG) and to the dissolution of pure spray dried powder. Concerning tableting, the developed formulation allowed for the preparation of tablets...... with a broad range of compaction pressures resulting in different porosities and tensile strengths. XRPD results showed that, overall, no crystallization occurred neither during tableting nor during long-term storage. Dissolution profiles of TAB SD IND–ARG showed an immediate release of IND by erosion...

  20. Hot Melt Extrusion and Spray Drying of Co-amorphous Indomethacin-Arginine With Polymers

    DEFF Research Database (Denmark)

    Lenz, Elisabeth; Löbmann, Korbinian; Rades, Thomas

    2017-01-01

    Co-amorphous drug-amino acid systems have gained growing interest as an alternative to common amorphous formulations which contain polymers as stabilizers. Several preparation methods have recently been investigated, including vibrational ball milling on a laboratory scale or spray drying......, and stability. Results were compared to those of spray-dried formulations with the same compositions and to spray-dried indomethacin-copovidone. Overall, stable co-amorphous systems could be prepared by extrusion without or with copovidone, which exhibited comparable molecular interaction properties...... to the respective spray-dried products, while phase separation was detected by differential scanning calorimetry in several cases. The formulations containing indomethacin in combination with arginine and copovidone showed enhanced dissolution behavior over the formulations with only copovidone or arginine....

  1. Colostrum and milk production in multiparous sows fed supplementary arginine during gestation and lactation

    DEFF Research Database (Denmark)

    Larsen, Uffe Krogh; Oksbjerg, Niels; Purup, Stig

    2016-01-01

    ) or isonitrogenous amounts of alanine (CON; n = 10) from d 30 of gestation until weaning on d 28 of lactation (in 2 blocks). Piglets were weighed 0, 12, 24, and 36 h after birth of the first piglet and on d 2, 7, 14, 21, and 28 in lactation for estimation of colostrum and milk intake. Colostrum samples obtained at 0......, 12, 24, and 36 h after parturition and milk from sows on d 3, 10, 17, and 24 of lactation were analyzed for macrochemical composition. Also, the content of IGF-I was determined in colostrum. Arginine supplementation decreased lactose and increased DM content of colostrum (P ... on colostrum or milk yield, piglet weight, piglet ADG, or fat content of colostrum and milk was observed (P > 0.10). Concentration of protein and IGF-I tended to be increased in ARG-fed sows. In conclusion, arginine supplementation of sows during gestation and lactation affected macrochemical composition...

  2. The L-arginine Pathway in Acute Ischemic Stroke and Severe Carotid Stenosis

    DEFF Research Database (Denmark)

    Molnar, Tihamer; Pusch, Gabriella; Papp, Viktoria

    2014-01-01

    BACKGROUND: Endothelial dysfunction is associated with increased levels of asymmetric dimethylarginine (ADMA) and symmetric dimethylarginine (SDMA) resulting in a decreased production of nitric oxide, which regulates the vascular tone. METHODS: Patients with acute ischemic stroke (AIS, n = 55......) and asymptomatic significant carotid stenosis (AsCS, n = 44) were prospectively investigated. L-arginine, ADMA, SDMA, S100 B, and high-sensitivity C-reactive protein (hsCRP) were serially measured within 6 hours after the onset of stroke, at 24 and 72 poststroke hours. All markers were compared with healthy...... subjects (n = 45). The severity of AIS was daily assessed by National Institute of Health Stroke Scale scoring. RESULTS: Even within 6 hours after the onset of stroke, L-arginine, ADMA, and SDMA were significantly higher in patients with AIS compared with both AsCS and healthy subjects. S100 B reflecting...

  3. Cloning of a protein arginine methyltransferase PRMT1 homologue from Schistosoma mansoni: Evidence for roles in nuclear receptor signaling and RNA metabolism

    International Nuclear Information System (INIS)

    Mansure, Jose Joao; Furtado, Daniel Rodrigues; Bastos de Oliveira, Francisco Meirelles; Rumjanek, Franklin David; Franco, Gloria Regina; Fantappie, Marcelo Rosado

    2005-01-01

    The most studied arginine methyltransferase is the type I enzyme, which catalyzes the transfer of an S-adenosyl-L-methionine to a broad spectrum of substrates, including histones, RNA-transporting proteins, and nuclear hormone receptor coactivators. We cloned a cDNA encoding a protein arginine methyltransferase in Schistosoma mansoni (SmPRMT1). SmPRMT1 is highly homologous to the vertebrate PRMT1 enzyme. In vitro methylation assays showed that SmPRMT1 recombinant protein was able to specifically methylate histone H4. Two schistosome proteins likely to be involved in RNA metabolism, SMYB1 and SmSmD3, that display a number of RGG motifs, were strongly methylated by SmPRMT1. In vitro GST pull-down assays showed that SMYB1 and SmSmD3 physically interacted with SmPRMT1. Additional GST pull-down assay suggested the occurrence of a ternary complex including SmPRMT1, SmRXR1 nuclear receptor, and the p160 (SRC-1) nuclear receptor coactivator. Together, these data suggest a mechanism by which SmPRMT1 plays a role in nuclear receptor-mediated chromatin remodeling and RNA transactions

  4. Comparison of the effects of NG-nitro-L-arginine and indomethacin on the hypercapnic cerebral blood flow increase in rats

    DEFF Research Database (Denmark)

    Wang, Qian; Pelligrino, D A; Paulson, O B

    1994-01-01

    The effects of NG-nitro-L-arginine (NOLAG), an inhibitor of nitric oxide synthase (NOS), and of indomethacin, an inhibitor of cyclooxygenase, on the rise in cerebral blood flow (CBF) accompanying increasing levels of hypercapnia (paCO2 = 40-135 mmHg) were studied in anesthetized rats. CBF...... with additional step increase in paCO2. Intracarotid infusion of 7.5 mg/kg NOLAG significantly attenuated the CO2-elicited CBF increase by about 45-65% at paCO2 values below 115 mmHg. Beyond this level, there was a lesser inhibition of about 27-35%. 30 mg/kg NOLAG had essentially the same effect as 7.5 mg....../kg NOLAG. 50 mg/kg NOLAG, given intraperitoneally (i.p.) twice daily for 4 days, also caused an attenuated CBF response to CO2, but the inhibitory effect was significantly less than with acute NOLAG administration in the paCO2 range of 61-90 mmHg. Infusion of L-arginine, 1 g/kg/h, prevented the effect of 7...

  5. Low dose vitamin C, vitamin E or L-arginine supplementation and ...

    African Journals Online (AJOL)

    The effect of chronic low-dose supplementation with vitamin C (300mg/day for 6 weeks in adults or 100mg/day for 6 weeks in children) or vitamin E (100 IU/day for 6 weeks in adults) or L-Arginine (1g/day for 6 weeks in adults) in ameliorating the pathophysiology and combating the deleterious effects of sickle cell disease in ...

  6. Evaluation of novel arginine based inhibitors of DDAH and investigations into radical hydroacylation of vinyl sulfonates

    OpenAIRE

    Khanom, N.

    2010-01-01

    The thesis is in two main sections. In the first section, studies on methylarginine processing enzymes are presented. Dimethyalrginine dimethylaminohydrolase (DDAH) is a class of enzymes involved in the metabolism of methylarginines ADMA and L-NMMA, which indirectly regulate physiological nitric oxide levels. It is desirable to inhibit excess NO in pathological situations, and the arginine mimetic L-257 is a DDAH inhibitor which reduces levels of NO. Synthesis of ester analo...

  7. Delayed nootropic effects of arginine vasopressin after early postnatal chronic administration to albino rat pups.

    Science.gov (United States)

    Kim, P A; Voskresenskaya, O G; Kamensky, A A

    2009-06-01

    Intranasal administration of arginine vasopressin (10 microg/kg) to albino rat pups had a strong nootropic effect during training with positive and negative reinforcement. This effect was different in animals of various age groups: training with positive reinforcement was improved in "adolescent" rats and pubertal animals, while during training with negative reinforcement, the nootropic effect of the peptide was more prolonged and persisted also in adult animals.

  8. Association of arginine vasopressin receptor 1a gene polymorphisms with hepatorenal syndrome

    International Nuclear Information System (INIS)

    Wang, C.; Luo, X.; Ye, J.; Liu, S.; Miu, L.; Bao, J.; Wang, F.; Yu, Z.

    2017-01-01

    To assess the association of arginine vasopressin receptor 1a gene single nucleotide polymorphisms with type I hepatorenal syndrome. Methods: The case-control study was conducted at the Hangzhou City Xixi Hospital, Hangzhou, China, from January 2012 to June 2014, and comprised patients with type I hepatorenal syndrome and individuals with cirrhosis who acted as the control group. Arginine vasopressin receptor 1a gene rs113481894 locus single nucleotide polymorphisms were analysed by high-resolution melting methods. Statistical analysis was performed using SPSS 17. Results: Of the 60 participants, 28(46.7%) were in the hepatorenal syndrome group and 32(53.3%) were controls. The mean age was 42.21+-11.30years in the hepatorenal syndrome group and 43.69+-12.60 in the control group (p=0.64). Mean total bilirubin, albumin and prothrombin activity levels were 154.76+-51.58, 49.30+-24.67 and 33.42+-3.69 in the hepatorenal syndrome group compared to 181.26+-64.46, 41.78+-17.52 and 32.98+-4.81 among controls (p=0.09, p=0.18 and p=0.70). Statistically significant differences were found in the distributions of arginine vasopressin receptor 1a gene rs113481894 locus T allele between type I hepatorenal syndrome patients and the control group (odds ratio= 2.230; p= 0.040). Conclusion: T allele located at arginine vasopressin receptor 1a receptor promoter rs113481894 locus may be associated with the pathogenesis of type I hepatorenal syndrome. (author)

  9. Molecular cloning and characterization of arginine kinase gene of Toxocara canis

    OpenAIRE

    Sahu, Shivani; Samanta, S.; Harish, D. R.; Sudhakar, N. R.; Raina, O. K.; Shantaveer, S. B.; Madhu, D. N.; Kumar, Ashok

    2013-01-01

    Toxocara canis is an important gastrointestinal nematode of dogs and also a causative agent of visceral larva migrans in humans. Arginine kinase (AK) gene is one of the important biomolecule of phosphagen kinase of T. canis which is emerging as an exciting novel diagnostic target in toxocarosis. The present study was carried out to clone and characterize AK gene of T. canis for future utilization as a diagnostic molecule. Total RNA was extracted from intact adult worms and reverse transcripti...

  10. The Effects Of L-Arginine And L-Name On Coronary Flow And Oxidative Stress In Isolated Rat Hearts

    Directory of Open Access Journals (Sweden)

    Sobot Tanja

    2015-12-01

    Full Text Available The aim of this experimental study was to assess the effects of the acute administration of L-arginine alone and in combination with L-NAME (a non-selective NO synthase inhibitor on the coronary flow and oxidative stress markers in isolated rat hearts. The experimental study was performed on hearts isolated from Wistar albino rats (n=12, male, 8 weeks old, body mass of 180-200 g. Retrograde perfusion of the isolated preparations was performed using a modified method according to the Langendorff technique with a gradual increase in the perfusion pressure (40–120 cmH2O. The following values were measured in the collected coronary effluents: coronary flow, released nitrites (NO production marker, superoxide anion radical and the index of lipid peroxidation (measured as thiobarbiturate reactive substances. The experimental protocol was performed under controlled conditions, followed by the administration of L-arginine alone (1 mmol and L-arginine (1 mmol + L-NAME (30 μmol. The results indicated that L-arginine did not significantly increase the coronary flow or the release of NO, TBARS and the superoxide anion radical. These effects were partially blocked by the joint administration of L-arginine + L-NAME, which indicated their competitive effect. Hence, the results of our study do not demonstrate significant effects of L-arginine administration on the coronary flow and oxidative stress markers in isolated rat hearts.

  11. Effects of Arginine Supplementation on Amino Acid Profiles in Blood and Tissues in Fed and Overnight-Fasted Rats

    Directory of Open Access Journals (Sweden)

    Milan Holecek

    2016-04-01

    Full Text Available Chronic arginine intake is believed to have favorable effects on the body. However, it might be hypothesized that excessive consumption of an individual amino acid exerts adverse effects on distribution and metabolism of other amino acids. We evaluated the effect of chronic intake of arginine on amino acid concentrations in blood plasma, liver, kidneys, and soleus and extensor digitorum longus muscles. Rats were fed a standard diet or a high-arginine diet (HAD for two months. Half of the animals in each group were sacrificed in the fed state, and the other half after fasting overnight. HAD increased blood plasma concentrations of urea, creatinine, arginine, and ornithine and decreased most other amino acids. Arginine and ornithine also increased in muscles and kidneys; an increase of lysine was observed in both muscle types. Methionine, phenylalanine, threonine, asparagine, glycine, serine, and taurine decreased in most tissues of HAD fed animals. Most of the effects of HAD disappeared after overnight fasting. It is concluded that (i enhanced dietary arginine intake alters distribution of almost all amino acids; and (ii to attain a better assessment of the effects of various nutritional interventions, an appropriate number of biochemical measurements must be performed in both postprandial and postabsorptive states.

  12. Influence of phenolic compounds on the growth and arginine deiminase system in a wine lactic acid bacterium

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    María R. Alberto

    2012-03-01

    Full Text Available The influence of seven phenolic compounds, normally present in wine, on the growth and arginine deiminase system (ADI of Lactobacillus hilgardii X1B, a wine lactic acid bacterium, was established. This system provides energy for bacterial growth and produces citrulline that reacts with ethanol forming the carcinogen ethyl carbamate (EC, found in some wines. The influence of phenolic compounds on bacterial growth was compound dependent. Growth and final pH values increased in presence of arginine. Arginine consumption decreased in presence of protocatechuic and gallic acids (31 and 17%, respectively and increased in presence of quercetin, rutin, catechin and the caffeic and vanillic phenolic acids (between 10 and 13%, respectively. ADI enzyme activities varied in presence of phenolic compounds. Rutin, quercetin and caffeic and vanillic acids stimulated the enzyme arginine deiminase about 37-40%. Amounts of 200 mg/L gallic and protocatechuic acids inhibited the arginine deiminase enzyme between 53 and 100%, respectively. Ornithine transcarbamylase activity was not modified at all concentrations of phenolic compounds. As gallic and protocatechuic acids inhibited the arginine deiminase enzyme that produces citrulline, precursor of EC, these results are important considering the formation of toxic compounds.

  13. Reverse Transcriptase-Containing Particles Induced in Rous Sarcoma Virus-Transformed Rat Cells by Arginine Deprivation

    Science.gov (United States)

    Kotler, Moshe; Weinberg, Eynat; Haspel, Osnat; Becker, Yechiel

    1972-01-01

    Incubation of rat cells transformed by Rous sarcoma virus (RSV) in an arginine-deficient medium resulted in accumulation of particles in the culture medium. Such particles did not appear when the transformed rat cells were incubated in a complete medium nor in the medium of primary rat cells which were incubated either in arginine-deficient or complete media. The particles which were released from the arginine-deprived transformed rat cells resemble C-type particles in their properties. These particles band in sucrose gradients at a density of 1.16 g/ml and contain 35S ribonucleic acid (RNA) molecules and a reverse transcriptase activity. Analysis of the cytoplasm of transformed and primary rat cells, deprived and undeprived of arginine, revealed the presence of reverse transcriptase-containing particles which banded in sucrose gradients at a density of 1.14 g/ml. These particles differed from the particles released into the medium by the arginine-deprived RSV-transformed rat cells. The deoxyribonucleic acid (DNA) molecules synthesized in vitro by the reverse transcriptase present in the particles isolated from the medium of arginine-deprived cells hybridized to RSV RNA, whereas the DNA synthesized by the cell-bound enzyme had no homology to RSV RNA. PMID:4116137

  14. l-Arginine induces antioxidant response to prevent oxidative stress via stimulation of glutathione synthesis and activation of Nrf2 pathway.

    Science.gov (United States)

    Liang, Mingcai; Wang, Zhengxuan; Li, Hui; Cai, Liang; Pan, Jianghao; He, Hongjuan; Wu, Qiong; Tang, Yinzhao; Ma, Jiapei; Yang, Lin

    2018-05-01

    Arginine is a conditionally essential amino acid. To elucidate the influence of l-arginine on the activation of endogenous antioxidant defence, male Wistar rats were orally administered daily with l-arginine at different levels of 25, 50, 100 mg/100 g body weight. After 7 and 14 days feeding, the antioxidative capacities and glutathione (GSH) contents in the plasma and in the liver were uniformly enhanced with the increasing consumption of l-arginine, whereas the oxidative stress was effectively suppressed by l-arginine treatment. After 14 days feeding, the mRNA levels and protein expressions of Keap1 and Cul3 were gradually reduced by increasing l-arginine intake, resulting that the nuclear factor Nrf2 was activated. Upon activation of Nrf2, the expressions of antioxidant responsive element (ARE)-dependent genes and proteins (GCLC, GCLM, GS, GR, GST, GPx, CAT, SOD, NQO1, HO-1) were up-regulated by l-arginine feeding, indicating an upward trend in antioxidant capacity uniformly with the increasing consumption of l-arginine. The present study demonstrates that the supplementation of l-arginine stimulates GSH synthesis and activates Nrf2 pathway, leading to the up-regulation of ARE-driven antioxidant expressions via Nrf2-Keap1 pathway. Results suggest the availability of l-arginine is a critical factor to suppress oxidative stress and induce an endogenous antioxidant response. Copyright © 2018 Elsevier Ltd. All rights reserved.

  15. Arginine and antioxidant supplement on performance in elderly male cyclists: a randomized controlled trial

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    Carpenter Catherine L

    2010-03-01

    Full Text Available Abstract Background Human exercise capacity declines with advancing age. These changes often result in loss of physical fitness and more rapid senescence. Nitric oxide (NO has been implicated in improvement of exercise capacity through vascular smooth muscle relaxation in both coronary and skeletal muscle arteries, as well as via independent mechanisms. Antioxidants may prevent nitric oxide inactivation by oxygen free radicals. The purpose of this study was to investigate the effects of an L-arginine and antioxidant supplement on exercise performance in elderly male cyclists. Methods This was a two-arm prospectively randomized double-blinded and placebo-controlled trial. Sixteen male cyclists were randomized to receive either a proprietary supplement (Niteworks®, Herbalife International Inc., Century City, CA or a placebo powder. Exercise parameters were assessed by maximal incremental exercise testing performed on a stationary cycle ergometer using breath-by-breath analysis at baseline, week one and week three. Results There was no difference between baseline exercise parameters. In the supplemented group, anaerobic threshold increased by 16.7% (2.38 ± 0.18 L/min, p 2 max between control and intervention groups at either week 1 or week 3 by comparison to baseline. Conclusion An arginine and antioxidant-containing supplement increased the anaerobic threshold at both week one and week three in elderly cyclists. No effect on VO2 max was observed. This study indicated a potential role of L-arginine and antioxidant supplementation in improving exercise performance in elderly.

  16. Caries-free subjects have high levels of urease and arginine deiminase activity

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    Evelyn REYES

    2014-06-01

    Full Text Available Objectives: This study investigated the relationship between urease and arginine deiminase system (ADS activities and dental caries through a cross-sectional study. Material and Methods: Urease and ADS activities were measured in saliva and plaque samples from 10 caries-free subjects and 13 caries-active. Urease activity was obtained from the ammonia produced by incubation of plaque and saliva samples in urea. ADS activity was obtained from the ammonia generated by the arginine-HCl and Tris-maleate buffer. Specific activity was defined as micromoles of ammonia per minute per milligram of protein. Shapiro-Wilk statistical test was used to analyze the distribution of the data, and Mann-Whitney test was used to determine the significance of the data. Results: The specific urease activity in saliva and plaque was significantly higher in individuals with low DMFT scores. ADS activity in saliva (6.050 vs 1.350, p=0.0154 and plaque (8.830 vs 1.210, p=0.025 was also higher in individuals with low DMFT scores. Conclusions: Caries-free subjects had a higher ammonia generation activity by urease and arginine deiminase system for both saliva and plaque samples than low caries-active subjects. High levels of alkali production in oral environment were related to caries-free subjects.

  17. Identification and characterization of an arginine kinase as a major allergen from silkworm (Bombyx mori) larvae.

    Science.gov (United States)

    Liu, Zhigang; Xia, Lixin; Wu, Yulan; Xia, Qingyou; Chen, Jiajie; Roux, Kenneth H

    2009-01-01

    The silkworm, Bombyx mori, is an important insect in the textile industry and its pupa are used in Chinese cuisine and traditional Chinese medicine. The silk, urine and dander of silkworms is often the cause of allergies in sericulture workers and the pupa has been found to be a food allergen in China. Recent studies have focused on reporting cases of silkworm allergies, but only a few studies have addressed the specific allergens present in the B. mori silkworm. We collected sera from 10 patients with a positive skin prick test to silkworm crude extract (SCE) and analyzed these samples by Western blot and ELISA. The cDNA of arginine kinase from the B. mori silkworm was also cloned and expressed in high yield in Escherichia coli. Allergenicity and cross-allergenicity of the recombinant B. mori arginine kinase (rBmAK) were investigated by ELISA inhibition assay. Collected sera all reacted to a 42-kDa protein in a Western blot with SCE as the antigen. Preincubation of sera with rBmAK eliminated the reactivity of the patients' sera to this 42-kDa band. All patient sera also exhibited positive reactivity to SCE in an ELISA assay. BmAK also demonstrated cross-reactivity with a recombinant AK from cockroach. Arginine kinase from the B. mori silkworm is a major allergen and crossreacts with cockroach AK. Copyright 2009 S. Karger AG, Basel.

  18. Structural alterations in rat myocardium induced by chronic l-arginine and l-NAME supplementation.

    Science.gov (United States)

    Hmaid, Amal Abdussalam Ali A; Markelic, Milica; Otasevic, Vesna; Masovic, Sava; Jankovic, Aleksandra; Korac, Bato; Korac, Aleksandra

    2018-03-01

    Structural changes affecting cardiomyocyte function may contribute to the pathophysiological remodeling underlying cardiac function impairment. Recent reports have shown that endogenous nitric oxide (NO) plays an important role in this process. In order to examine the role of NO in cardiomyocyte remodeling, male rats were acclimated to room temperature (22 ± 1 °C) or cold (4 ± 1 °C) and treated with 2.25% l-arginine·HCl or 0.01% l-NAME (N ω -nitro-l-arginine methyl ester)·HCl for 45 days. Untreated groups served as controls. Right heart ventricles were routinely prepared for light microscopic examination. Stereological estimations of volume densities of cardiomyocytes, surrounding blood vessels and connective tissue, as well as the morphometric measurements of cardiomyocyte diameters were performed. Tissue sections were also analyzed for structural alterations. We observed that both l-arginine and l-NAME supplementation induced cardiomyocyte hypertrophy, regardless of ambient temperature. However, cardiomyocyte hypertrophy was associated with fibrosis and extra collagen deposition only in the l-NAME treated group. Taken together, our results suggest that NO has a modulatory role in right heart ventricle remodeling by coordinating hypertrophy of cardiomyocytes and fibrous tissue preventing cardiac fibrosis.

  19. Preparing hydraulic cement from oil-shale residue

    Energy Technology Data Exchange (ETDEWEB)

    1921-08-28

    A process for preparation of hydraulic cement from oil-shale residue is characterized in that, as flux is used, rich-in-lime poor-in-sulfur portland-cement clinker, by which the usual gypsum addition, is avoided.

  20. Bioconversion of sago residue into value added products | Awg ...

    African Journals Online (AJOL)

    ... value added products. DS Awg-Adeni, S Abd-Aziz,