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Sample records for agmatine pretreatment protects

  1. Protective mechanism of agmatine pretreatment on RGC-5 cells injured by oxidative stress

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    Y. Iizuka

    2010-04-01

    Full Text Available Agmatine has neuroprotective effects on retinal ganglion cells (RGCs as well as cortical and spinal neurons. It protects RGCs from oxidative stress even when it is not present at the time of injury. As agmatine has high affinity for various cellular receptors, we assessed protective mechanisms of agmatine using transformed RGCs (RGC-5 cell line. Differentiated RGC-5 cells were pretreated with 100 μM agmatine and consecutively exposed to 1.0 mM hydrogen peroxide (H2O2. Cell viability was determined by measuring lactate dehydrogenase (LDH, and the effects of selective alpha 2-adrenergic receptor antagonist yohimbine (0-500 nM and N-methyl-D-aspartic acid (NMDA receptor agonist NMDA (0-100 µM were evaluated. Agmatine’s protective effect was compared to a selective NMDA receptor antagonist MK-801. After a 16-h exposure to H2O2, the LDH assay showed cell loss greater than 50%, which was reduced to about 30% when agmatine was pretreated before injury. Yohimbine almost completely inhibited agmatine’s protective effect, but NMDA did not. In addition, MK-801 (0-100 µM did not significantly attenuate the H2O2-induced cytotoxicity. Our results suggest that neuroprotective effects of agmatine on RGCs under oxidative stress may be mainly attributed to the alpha 2-adrenergic receptor signaling pathway.

  2. Protective effect of agmatine in acute chlorpromazine hepatotoxicity in rats

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    Bratislav Dejanovic

    2014-01-01

    Full Text Available The present study focused on potentially beneficial effects of agmatine on oxidative stress development in the liver during chlorpromazine treatment in rats. We wanted to examine the role of reactive oxygen species and efficiency of antioxidant protection through the determination of malondylaldehyde and total glutathione concentrations in rat liver homogenate, as well as plasma concentrations of malonylaldehyde and sulfhydryl groups after the treatment. Also, liver tissue sections were examined to follow histological changes. Chlorpromazine was applied intraperitoneally at a single dose of 38.7 mg/kg b.w. The second group was treated with both chlorpromazine (at a single dose of 38.7 mg/kg b.w. and agmatine (at a single dose of 75 mg/kg b.w.. Agmatine was applied immediately after the chlorpromazine. The control group was treated with 0.9% saline solution in the same manner. Rats were sacrificed by decapitation 24 h after the treatment and biochemical and immunohistochemical examinations were performed. Analysis of data showed that treatment with agmatine significantly attenuated the oxidative stress indicators as evidenced by lowering malonylaldehyde concentrations in the liver and in plasma while not affecting liver concentrations of total glutathione and plasma concentration of sulfhydryl groups. Additionally, histological evaluation revealed the improvement of liver damage in this respect. The presented data indicated that intraperitoneally administered agmatine protects against chlorpromazine-induced liver disease in rats.

  3. Protective effects of agmatine on doxorubicin-induced chronic cardiotoxicity in rat.

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    Yarmohmmadi, Fatemeh; Rahimi, Nastaran; Faghir-Ghanesefat, Hedyeh; Javadian, Nina; Abdollahi, Alireza; Pasalar, Parvin; Jazayeri, Farahnaz; Ejtemaeemehr, Shahram; Dehpour, Ahmad Reza

    2017-02-05

    The detrimental cardio-toxic effect of doxorubicin, an effective chemotherapeutic agent, limited its clinical use. It has been claimed that doxorubicin cardio-toxicity occurs through calcium ions (Ca 2+ ) overload and reactive oxygen species production. Agmatine, an endogenous imidazoline receptor agonist, induce uptake of cytosolic Ca 2+ and cause an increase in activity of calcium pumps, including Ca 2+ -ATPase. Also it shows self-scavenging effect against reactive oxygen species production. Therefore, present study was designed to investigate the effects of agmatine against chronic cardio-toxicity of doxorubicin in rats. Male wistar rats were intraperitoneally injected with doxorubicin and agmatine four times a week for a month. Agmatine significantly alleviate the adverse effect of doxorubicin on left ventricular papillary muscle stimulation threshold and contractibility. Chronic co-administration of agmatine with doxorubicin blocked electrocardiographic changes induced by doxorubicin. In addition, agmatine improved body weight and decreased the mortality rate of animals by doxorubicin. Moreover, reversing the doxorubicin induced myocardial lesions was observed in animals treated by agmatine. A significant rise in the total antioxidant capacity of rat plasma was achieved in agmatine-treated animals in comparison to doxorubicin. To conclude, agmatine may improve therapeutic outcomes of doxorubicin since it exerts protective effects against doxorubicin-induced chronic cardiotoxicity in rats. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Protective effects of agmatine on lipopolysaccharide-injured microglia and inducible nitric oxide synthase activity.

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    Ahn, Soo Kyung; Hong, Samin; Park, Yu Mi; Choi, Ja Yong; Lee, Won Taek; Park, Kyung Ah; Lee, Jong Eun

    2012-12-17

    Proinflammatory factors released from activated microglia contribute to maintaining homeostasis against various noxious stimuli in the central nervous system. If excessive, however, they may initiate a pathologic neuroinflammatory process. In this investigation, we evaluated whether agmatine, a primary polyamine known to protect neurons, reduces lipopolysaccharide (LPS)-induced damage to microglia in vitro and in vivo. For in vitro study, BV2-immortalized murine microglia were exposed to LPS with agmatine treatment. After 24hours, cell viability and the amount of nitrite generated were determined. For in vivo study, LPS was microinjected into the corpus callosum of adult male albino mice. Agmatine was intraperitoneally administered at the time of injury. Brains were evaluated 24hours after LPS microinjection to check for immunoreactivity with a microglial marker of ionized calcium binding adaptor molecule 1 (Iba1) and inducible nitric oxide synthase (iNOS). Using western blot analysis, protein expression of iNOS as well as that of the proinflammatory cytokines, tumor necrosis factor (TNF)-α and interleukin (IL)-1β, was determined. Agmatine significantly reduced the LPS-induced BV2 microglial cytotoxicity from over 80% to less than 60% (pAgmatine also decreased the activities of microglia and iNOS induced by LPS microinjection into corpus callosum. Our findings reveal that agmatine attenuates LPS-induced microglial damage and suggest that agmatine may serve as a novel therapeutic strategy for neuroinflammatory diseases. Copyright © 2012 Elsevier Inc. All rights reserved.

  5. Agmatine protects against cell damage induced by NMDA and glutamate in cultured hippocampal neurons

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    Wang, Wei-Ping; Iyo, Abiye H.; Miguel-Hidalgo, Javier; Regunathan, Soundar; Zhu, Meng-Yang

    2010-01-01

    Agmatine is a polyamine and has been considered as a novel neurotransmitter or neuromodulator in the central nervous system. In the present study, the neuroprotective effect of agmatine against cell damage caused by N-methyl-d-aspartate (NMDA) and glutamate was investigated in cultured rat hippocampal neurons. Lactate dehydrogenase (LDH) activity assay, β-tubulin III immunocytochemical staining and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate (dUTP) nick end-labeling (TUNEL) assay were conducted to detect cell damage. Exposure of 12-day neuronal cultures of rat hippocampus to NMDA or glutamate for 1 h caused a concentration-dependent neurotoxicity, as indicated by the significant increase in released LDH activities. Addition of 100 µM agmatine into media ablated the neurotoxicity induced by NMDA or glutamate, an effect also produced by the specific NMDA receptor antagonist dizocilpine hydrogen maleate (MK801). Arcaine, an analog of agmatine with similar structure as agmatine, fully prevented the NMDA- or glutamate-induced neuronal damage. Spermine and putrescine, the endogenous polyamine and metabolic products of agmatine without the guanidine moiety of agmatine, failed to show this effect, indicating a structural relevance for this neuroprotection. Immunocytochemical staining and TUNEL assay confirmed the findings in the LDH measurement. That is, agmatine and MK801 markedly attenuated NMDA-induced neuronal death and significantly reduced TUNEL-positive cell numbers induced by exposure of cultured hippocampal neurons to NMDA. Taken together, these results demonstrate that agmatine can protect cultured hippocampal neurons from NMDA- or glutamate-induced excitotoxicity, through a possible blockade of the NMDA receptor channels or a potential anti-apoptotic property. PMID:16546145

  6. Agmatine induces Nrf2 and protects against corticosterone effects in hippocampal neuronal cell line.

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    Freitas, Andiara E; Egea, Javier; Buendía, Izaskun; Navarro, Elisa; Rada, Patricia; Cuadrado, Antonio; Rodrigues, Ana Lúcia S; López, Manuela G

    2015-01-01

    Hyperactivation of the hypothalamic-pituitary-adrenal axis is a common finding in major depression; this may lead to increased levels of cortisol, which are known to cause oxidative stress imbalance and apoptotic neuronal cell death, particularly in the hippocampus, a key region implicated in mood regulation. Agmatine, an endogenous metabolite of L-arginine, has been proposed for the treatment of major depression. Corticosterone induced apoptotic cell death and increased ROS production in cultured hippocampal neuronal cells, effects that were abolished in a concentration- and time-dependent manner by agmatine. Interestingly, the combination of sub-effective concentrations of agmatine with fluoxetine or imipramine afforded synergic protection. The neuroprotective effect of agmatine was abolished by yohimbine (α2-adrenoceptor antagonist), ketanserin (5-HT2A receptor antagonist), LY294002 (PI3K inhibitor), PD98059 (MEK1/2 inhibitor), SnPP (HO-1 inhibitor), and cycloheximide (protein synthesis inhibitor). Agmatine increased Akt and ERK phosphorylation and induced the transcription factor Nrf2 and the proteins HO-1 and GCLc; induction of these proteins was prevented by yohimbine, ketanserin, LY294002, and PD98059. In conclusion, agmatine affords neuroprotection against corticosterone effects by a mechanism that implicates Nrf2 induction via α2-adrenergic and 5-HT2A receptors, Akt and ERK pathways, and HO-1 and GCLc expression.

  7. Agmatine Protects against Zymosan-Induced Acute Lung Injury in Mice by Inhibiting NF-κB-Mediated Inflammatory Response

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    Xuanfei Li

    2014-01-01

    Full Text Available Acute lung injury (ALI is characterized by overwhelming lung inflammation and anti-inflammation treatment is proposed to be a therapeutic strategy for ALI. Agmatine, a cationic polyamine formed by decarboxylation of L-arginine, is an endogenous neuromodulator that plays protective roles in diverse central nervous system (CNS disorders. Consistent with its neuromodulatory and neuroprotective properties, agmatine has been reported to have beneficial effects on depression, anxiety, hypoxic ischemia, Parkinson’s disease, and gastric disorder. In this study, we tested the effect of agmatine on the lung inflammation induced by Zymosan (ZYM challenge in mice. We found that agmatine treatment relieved ZYM-induced acute lung injury, as evidenced by the reduced histological scores, wet/dry weight ratio, and myeloperoxidase activity in the lung tissue. This was accompanied by reduced levels of TNF-α, IL-1β, and IL-6 in lung and bronchoalveolar lavage fluid and decreased iNOS expression in lung. Furthermore, agmatine inhibited the phosphorylation and degradation of IκB and subsequently blocked the activation of nuclear factor (NF-κB induced by Zymosan. Taken together, our results showed that agmatine treatment inhibited NF-κB signaling in lungs and protected mice against ALI induced by Zymosan, suggesting agmatine may be a potential safe and effective approach for the treatment of ALI.

  8. Agmatine protects against zymosan-induced acute lung injury in mice by inhibiting NF-κB-mediated inflammatory response.

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    Li, Xuanfei; Liu, Zheng; Jin, He; Fan, Xia; Yang, Xue; Tang, Wanqi; Yan, Jun; Liang, Huaping

    2014-01-01

    Acute lung injury (ALI) is characterized by overwhelming lung inflammation and anti-inflammation treatment is proposed to be a therapeutic strategy for ALI. Agmatine, a cationic polyamine formed by decarboxylation of L-arginine, is an endogenous neuromodulator that plays protective roles in diverse central nervous system (CNS) disorders. Consistent with its neuromodulatory and neuroprotective properties, agmatine has been reported to have beneficial effects on depression, anxiety, hypoxic ischemia, Parkinson's disease, and gastric disorder. In this study, we tested the effect of agmatine on the lung inflammation induced by Zymosan (ZYM) challenge in mice. We found that agmatine treatment relieved ZYM-induced acute lung injury, as evidenced by the reduced histological scores, wet/dry weight ratio, and myeloperoxidase activity in the lung tissue. This was accompanied by reduced levels of TNF-α, IL-1β, and IL-6 in lung and bronchoalveolar lavage fluid and decreased iNOS expression in lung. Furthermore, agmatine inhibited the phosphorylation and degradation of IκB and subsequently blocked the activation of nuclear factor (NF)-κB induced by Zymosan. Taken together, our results showed that agmatine treatment inhibited NF-κB signaling in lungs and protected mice against ALI induced by Zymosan, suggesting agmatine may be a potential safe and effective approach for the treatment of ALI.

  9. Agmatine protects retinal ganglion cells from hypoxia-induced apoptosis in transformed rat retinal ganglion cell line

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    Kim Chan

    2007-10-01

    Full Text Available Abstract Background Agmatine is an endogenous polyamine formed by the decarboxylation of L-arginine. We investigated the protective effects of agmatine against hypoxia-induced apoptosis of immortalized rat retinal ganglion cells (RGC-5. RGC-5 cells were cultured in a closed hypoxic chamber (5% O2 with or without agmatine. Cell viability was determined by lactate dehydrogenase (LDH assay and apoptosis was examined by annexin V and caspase-3 assays. Expression and phosphorylation of mitogen-activated protein kinases (MAPKs; JNK, ERK p44/42, and p38 and nuclear factor-kappa B (NF-κB were investigated by Western immunoblot analysis. The effects of agmatine were compared to those of brain-derived neurotrophic factor (BDNF, a well-known protective neurotrophin for retinal ganglion cells. Results After 48 hours of hypoxic culture, the LDH assay showed 52.3% cell loss, which was reduced to 25.6% and 30.1% when agmatine and BDNF were administered, respectively. This observed cell loss was due to apoptotic cell death, as established by annexin V and caspase-3 assays. Although total expression of MAPKs and NF-κB was not influenced by hypoxic injury, phosphorylation of these two proteins was increased. Agmatine reduced phosphorylation of JNK and NF-κB, while BDNF suppressed phosphorylation of ERK and p38. Conclusion Our results show that agmatine has neuroprotective effects against hypoxia-induced retinal ganglion cell damage in RGC-5 cells and that its effects may act through the JNK and NF-κB signaling pathways. Our data suggest that agmatine may lead to a novel therapeutic strategy to reduce retinal ganglion cell injury related to hypoxia.

  10. Agmatine protects retinal ganglion cells from hypoxia-induced apoptosis in transformed rat retinal ganglion cell line

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    Hong, Samin; Lee, Jong Eun; Kim, Chan Yun; Seong, Gong Je

    2007-01-01

    Background Agmatine is an endogenous polyamine formed by the decarboxylation of L-arginine. We investigated the protective effects of agmatine against hypoxia-induced apoptosis of immortalized rat retinal ganglion cells (RGC-5). RGC-5 cells were cultured in a closed hypoxic chamber (5% O2) with or without agmatine. Cell viability was determined by lactate dehydrogenase (LDH) assay and apoptosis was examined by annexin V and caspase-3 assays. Expression and phosphorylation of mitogen-activated protein kinases (MAPKs; JNK, ERK p44/42, and p38) and nuclear factor-kappa B (NF-κB) were investigated by Western immunoblot analysis. The effects of agmatine were compared to those of brain-derived neurotrophic factor (BDNF), a well-known protective neurotrophin for retinal ganglion cells. Results After 48 hours of hypoxic culture, the LDH assay showed 52.3% cell loss, which was reduced to 25.6% and 30.1% when agmatine and BDNF were administered, respectively. This observed cell loss was due to apoptotic cell death, as established by annexin V and caspase-3 assays. Although total expression of MAPKs and NF-κB was not influenced by hypoxic injury, phosphorylation of these two proteins was increased. Agmatine reduced phosphorylation of JNK and NF-κB, while BDNF suppressed phosphorylation of ERK and p38. Conclusion Our results show that agmatine has neuroprotective effects against hypoxia-induced retinal ganglion cell damage in RGC-5 cells and that its effects may act through the JNK and NF-κB signaling pathways. Our data suggest that agmatine may lead to a novel therapeutic strategy to reduce retinal ganglion cell injury related to hypoxia. PMID:17908330

  11. Agmatine Protects Against 6-OHDA-Induced Apoptosis, and ERK and Akt/GSK Disruption in SH-SY5Y Cells.

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    Amiri, Esmat; Ghasemi, Rasoul; Moosavi, Maryam

    2016-08-01

    6-Hydroxydopamine (6-OHDA), a metabolite of dopamine is known to induce dopaminergic cell toxicity which makes that a suitable agent inducing an experimental model of Parkinson's disease (PD). Agmatine has been shown to protect against some cellular and animal PD models. This study was aimed to assess whether agmatine prevents 6-OHDA-induced SH-SY5Y cell death and if yes, then how it affects Akt/glycogen synthesis kinase-3β (GSK-3β) and extracellular signal-regulated kinases (ERK) signals. The cells were treated with different drugs, and their viability was examined via MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide) assay and morphological observation. Western blot studies were done to assess cleaved caspase-3, Akt/GSK-3β, and ERK proteins. 6-OHDA-induced cell death and caspase-3 cleavage, while agmatine prevented those changes. 6-OHDA also decreased the amount of phosphorylated Akt (pAkt)/Akt while increased GSK-3β activity which was prevented by agmatine. Additionally, this toxin increased pERK/ERK ratio which was averted again by agmatine. The PI3/Akt inhibitor, LY294002, impeded the changes induced by agmatine, while ERK inhibitor (PD98059) did not disturb the effects of agmatine, and by itself, it preserved the cells against 6-OHDA toxicity. This study revealed that agmatine is protective in 6-OHDA model of PD and affects Akt/GSK-3β and ERK pathways.

  12. Agmatine protects Müller cells from high-concentration glucose-induced cell damage via N-methyl-D-aspartic acid receptor inhibition.

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    Han, Ning; Yu, Li; Song, Zhidu; Luo, Lifu; Wu, Yazhen

    2015-07-01

    Neural injury is associated with the development of diabetic retinopathy. Müller cells provide structural and metabolic support for retinal neurons. High glucose concentrations are known to induce Müller cell activity. Agmatine is an endogenous polyamine, which is enzymatically formed in the mammalian brain and has exhibited neuroprotective effects in a number of experimental models. The aims of the present study were to investigate whether agmatine protects Müller cells from glucose-induced damage and to explore the mechanisms underlying this process. Lactate dehydrogenase activity and tumor necrosis factor-α mRNA expression were significantly reduced in Müller cells exposed to a high glucose concentration, following agmatine treatment, compared with cells not treated with agmatine. In addition, agmatine treatment inhibited glucose-induced Müller cell apoptosis, which was associated with the regulation of Bax and Bcl-2 expression. Agmatine treatment suppressed glucose-induced phosphorylation of mitogen-activated protein kinase (MAPK) protein in Müller cells. The present study demonstrated that the protective effects of agmatine on Müller cells were inhibited by N-methyl-D-aspartic acid (NMDA). The results of the present study suggested that agmatine treatment protects Müller cells from high-concentration glucose-induced cell damage. The underlying mechanisms may relate to the anti-inflammatory and antiapoptotic effects of agmatine, as well as to the inhibition of the MAPK pathway, via NMDA receptor suppression. Agmatine may be of use in the development of novel therapeutic approaches for patients with diabetic retinopathy.

  13. Role of nitric oxide in additive anticonvulsant effects of agmatine and morphine.

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    Payandemehr, Borna; Rahimian, Reza; Bahremand, Arash; Ebrahimi, Ali; Saadat, Seyedehpariya; Moghaddas, Peiman; Fadakar, Kaveh; Derakhshanian, Hoda; Dehpour, Ahmad Reza

    2013-06-13

    The anticonvulsant effects of agmatine, an endogenous polyamine and a metabolite of l-arginine, have been shown in various experimental seizure models. Agmatine also potentiates the anti-seizure activity of morphine. The present study aimed to investigate a possible involvement of nitric oxide (NO) pathway in the protection by agmatine and morphine co-administration against pentylenetetrazole (PTZ) -induced seizure in male mice. To this end, the thresholds for the clonic seizures induced by the intravenous administration of PTZ, a GABA antagonist, were assessed. Intraperitoneal administration of morphine at lower dose (1mg/kg) increased the seizure threshold. Also intraperitoneal administration of agmatine (5 and 10mg/kg) increased the seizure threshold significantly. Combination of subeffective doses of morphine and agmatine led to potent anticonvulsant effects. Non-effective doses of morphine (0.1 and 0.5mg/kg) were able to induce anticonvulsant effects in mice pretreated with agmatine (3mg/kg). Concomitant administration of either the non-selective nitric oxide synthase (NOS) inhibitor L-NAME (1, 5mg/kg, i.p.) or the selective NOS inhibitor 7-NI (15, 30mg/kg, i.p.), with an ineffective combination of morphine (0.1mg/kg) plus agmatine (1mg/kg) produced significant anticonvulsant impacts. Moreover, the NO precursor, l-arginine (30, 60mg/kg, i.p.), inhibited the anticonvulsant action of agmatine (3mg/kg) plus morphine (0.5mg/kg) co-administration. Our results indicate that pretreatment of animals with agmatine enhances the anticonvulsant effects of morphine via a mechanism which may involve the NO pathway. Copyright © 2013 Elsevier Inc. All rights reserved.

  14. Agmatine protection against chlorpromazine-induced forebrain cortex injury in rats.

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    Dejanovic, Bratislav; Stevanovic, Ivana; Ninkovic, Milica; Stojanovic, Ivana; Lavrnja, Irena; Radicevic, Tatjana; Pavlovic, Milos

    2016-03-01

    This study was conducted to investigate whether agmatine (AGM) provides protection against oxidative stress induced by treatment with chlorpromazine (CPZ) in Wistar rats. In addition, the role of reactive oxygen species and efficiency of antioxidant protection in the brain homogenates of forebrain cortexes prepared 48 h after treatment were investigated. Chlorpromazine was applied intraperitoneally (i.p.) in single dose of 38.7 mg/kg body weight (BW) The second group was treated with both CPZ and AGM (75 mg/kg BW). The control group was treated with 0.9% saline solution in the same manner. All tested compounds were administered i.p. in a single dose. Rats were sacrificed by decapitation 48 h after treatment Treatment with AGM significantly attenuated the oxidative stress parameters and restored antioxidant capacity in the forebrain cortex. The data indicated that i.p. administered AGM exerted antioxidant action in CPZ-treated animals. Moreover, reactive astrocytes and microglia may contribute to secondary nerve-cell damage and participate in the balance of destructive vs. protective actions involved in the pathogenesis after poisoning.

  15. Evidence for the gastric cytoprotective effect of centrally injected agmatine.

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    Zádori, Zoltán S; Tóth, Viktória E; Fehér, Ágnes; Philipp, Kirsch; Németh, József; Gyires, Klára

    2014-09-01

    Agmatine (decarboxylated arginine) exerts cytoprotective action in several tissues, such as in the brain, heart or kidneys, but there is still controversy over the effects of agmatine on the gastric mucosa. The aim of the present study was to reveal the potential gastroprotective action of agmatine by using an acid-independent ulcer model to clarify which receptors and peripheral factors are involved in it. Gastric mucosal damage was induced by acidified ethanol. Mucosal levels of calcitonin gene-related peptide (CGRP) and somatostatin were determined by radioimmunoassay. For analysis of gastric motor activity the rubber balloon method was used. It was found that agmatine given intracerebroventricularly (i.c.v., 0.044-220 nmol/rat) significantly inhibited the development of ethanol-induced mucosal damage, while in the case of intraperitoneal injection (0.001-50mg/kg i.p.) it had only a minor effect. The central gastroprotective action of agmatine was completely antagonized by mixed alpha2-adrenoceptor and imidazoline I1 receptor antagonists (idazoxan, efaroxan), but only partially by yohimbine (selective alpha2-adrenoceptor antagonist) and AGN 192403 (selective I1 receptor ligand, putative antagonist). It was also inhibited by the non-selective opioid-receptor antagonist naloxone and the selective δ-opioid receptor antagonist naltrindole, but not by β-funaltrexamine and nor-Binaltorphimine (selective μ- and κ-opioid receptor antagonists, respectively). Furthermore, the effect of agmatine was antagonized by bilateral cervical vagotomy and by pretreatment with indomethacin and NG-nitro-l-arginine. Agmatine also reversed the ethanol-induced reduction of gastric mucosal CGRP and somatostatin content, but did not have any significant effect on gastric motor activity. These results indicate that agmatine given centrally induces gastric cytoprotection, which is mediated by central imidazoline I1 receptors, alpha2-adrenoceptors and δ-opioid receptors. Activation of

  16. Evaluation of the protective effect of agmatine against cisplatin nephrotoxicity with 99mTc-DMSA renal scintigraphy and cystatin-C.

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    Salihoglu, Yavuz Sami; Elri, Tarik; Gulle, Kanat; Can, Murat; Aras, Mustafa; Ozacmak, Hale Sayan; Cabuk, Mehmet

    2016-10-01

    The aim of the current study was to investigate whether agmatine (AGM) has a protective effect against cisplatin-induced nephrotoxicity. Thirty-two rats were randomly divided into four groups: (1) Saline (control); (2) Cisplatin (CDDP; 7.5 mg/kg intraperitoneally); (3) Agmatine (AGM; 10 mg/kg intraperitoneally); (4) Cisplatin plus agmatine (CDDP + AGM). Agmatine was given before and two consecutive days after cisplatin injection. All the animals underwent renal scintigraphy with 99mTc-DMSA. The levels of serum creatinine, cystatin C, and blood urea nitrogen (BUN) were measured in addition to examination of the tissue samples with light microscopy. Acute renal injury was assessed with biochemical analyses, scintigraphic imaging, and histopathological evaluation. In the cisplatin group, the levels of BUN, creatinine, and cystatin C were significantly higher than that of the controls. Histopathological examination showed remarkable damage of tubular and glomerular structures. Additionally, cisplatin caused markedly decreased renal 99mTc-DMSA uptake. AGM administration improved renal functions. Serum creatinine, BUN, and cystatin C levels had a tendency to normalize and, scintigraphic and histopathological findings showed significantly less evidence of renal toxicity than those observed in animals receiving cisplatin alone. Our data indicate that AGM has a protective effect against cisplatin-induced nephrotoxicity. Therefore, it may improve the therapeutic index of cisplatin. In addition, the early renal damage induced by cisplatin and protective effects of AGM against cisplatin nephrotoxicity was accurately demonstrated with 99mTc-DMSA renal scintigraphy.

  17. Protective effects of agmatine against D-galactosamine and lipopolysaccharide-induced fulminant hepatic failure in mice.

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    El-Agamy, Dina S; Makled, Mirhan N; Gamil, Nareman M

    2014-06-01

    Fulminant hepatic failure (FHF) is a life-threatening syndrome characterized by massive hepatic necrosis and high mortality. There is no effective therapy for the disease other than liver transplantation. This study aimed to investigate the effect of agmatine, inducible nitric oxide synthase (iNOS) inhibitor, on D-galactosamine and lipopolysaccharide (GalN/LPS)-induced FHF in mice and explore its possible mechanism(s). Male Swiss albino mice were injected with a single dose agmatine (14 mg/kg, IP) 8 h prior to challenge with a single intraperitoneal injection of both GalN (800 mg/kg) and LPS (50 μg/kg). Agmatine significantly attenuated all GalN/LPS-induced biochemical and pathological changes in liver. It prevented the increase of serum transaminases and alkaline phosphatase (ALP). In addition, agmatine markedly attenuated GalN/LPS-induced necrosis and inflammation. Agmatine significantly reduced oxidative stress and enhanced antioxidant enzymes. Importantly, agmatine decreased total nitric oxide (NO) and pro-inflammatory cytokine, tumor necrosis factor-alpha (TNF-α). These findings reveal that agmatine has hepatoprotective effects against GalN/LPS-induced FHF in mice that may be related to its ability to suppress oxidative stress, NO synthesis and TNF-α production. Therefore, agmatine may serve as a novel therapeutic strategy for hepatic inflammatory diseases.

  18. Agmatine attenuates intestinal ischemia and reperfusion injury by reducing oxidative stress and inflammatory reaction in rats.

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    Turan, Inci; Ozacmak, Hale Sayan; Ozacmak, V Haktan; Barut, Figen; Araslı, Mehmet

    2017-11-15

    Oxidative stress and inflammatory response are major factors causing several tissue injuries in intestinal ischemia and reperfusion (I/R). Agmatine has been reported to attenuate I/R injury of various organs. The present study aims to analyze the possible protective effects of agmatine on intestinal I/R injury in rats. Four groups were designed: sham control, agmatine-treated control, I/R control, and agmatine-treated I/R groups. IR injury of small intestine was induced by the occlusion of the superior mesenteric artery for half an hour to be followed by a 3-hour-long reperfusion. Agmatine (10mg/kg) was administered intraperitoneally before reperfusion period. After 180min of reperfusion period, the contractile responses to both carbachol and potassium chloride (KCl) were subsequently examined in an isolated-organ bath. Malondialdehyde (MDA), reduced glutathione (GSH), and the activity of myeloperoxidase (MPO) were measured in intestinal tissue. Plasma cytokine levels were determined. The expression of the intestinal inducible nitric oxide synthase (iNOS) was also assessed by immunohistochemistry. The treatment with agmatine appeared to be significantly effective in reducing the MDA content and MPO activity besides restoring the content of GSH. The treatment also attenuated the histological injury. The increases in the I/R induced expressions of iNOS, IFN-γ, and IL-1α were brought back to the sham control levels by the treatment as well. Our findings indicate that the agmatine pretreatment may ameliorate reperfusion induced injury in small intestine mainly due to reducing inflammatory response and oxidative stress. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Protective Effects of Agmatine against Chlorpromazine- Induced Toxicity in the Liver of Wistar Rats

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    Dejanović Bratislav

    2016-03-01

    Full Text Available The metabolic pathways of chlorpromazine (CPZ toxicity were tracked by assessing oxidative/nitrosative stress markers. The main objective of the study was to test the hypothesis that agmatine (AGM prevents oxidative/nitrosative stress in the liver of Wistar rats 15 days after administration of CPZ. All tested substances were administered intraperitoneally (i.p. for 15 consecutive days. The rats were divided into four groups: the control group (C, 0.9 % saline solution, the CPZ group (CPZ, 38.7 mg/kg b.w., the CPZ+AGM group (AGM, 75 mg/kg b.w. immediately after CPZ, 38.7 mg/kg b.w. i.p. and the AGM group (AGM, 75 mg/kg b.w..

  20. Retinal protective effects of topically administered agmatine on ischemic ocular injury caused by transient occlusion of the ophthalmic artery

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    S. Hong

    2012-03-01

    Full Text Available Agmatine, an endogenous polyamine and putative neuromodulator, is known to have neuroprotective effects on various neurons in the central nervous system. We determined whether or not topically administered agmatine could reduce ischemic retinal injury. Transient ocular ischemia was achieved by intraluminal occlusion of the middle cerebral artery of ddY mice (30-35 g for 2 h, which is known to also induce occlusion of the ophthalmic artery. In the agmatine group (N = 6, a 1.0 mM agmatine-containing ophthalmic solution was administered four times daily for 2 weeks before occlusion. In the control group (N = 6, a 0.1% hyaluronic acid ophthalmic solution was instilled at the same times. At 22 h after reperfusion, the eyeballs were enucleated and the retinal sections were stained by terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL. Transient ocular ischemia induced apoptosis of retinal cells in the entire retinal layer, and topically administered agmatine can significantly reduce this ischemic retinal injury. The proportion of apoptotic cells was definitely decreased (P < 0.001; Kruskal-Wallis test. Overall, we determined that topical agmatine application effectively decreases retinal damage in an in vivo ocular ischemic injury model. This implies that agmatine is a good candidate as a direct neuroprotective agent for eyes with ocular ischemic diseases.

  1. Retinal protective effects of topically administered agmatine on ischemic ocular injury caused by transient occlusion of the ophthalmic artery

    Science.gov (United States)

    Hong, S.; Hara, H.; Shimazawa, M.; Hyakkoku, K.; Kim, C.Y.; Seong, G.J.

    2012-01-01

    Agmatine, an endogenous polyamine and putative neuromodulator, is known to have neuroprotective effects on various neurons in the central nervous system. We determined whether or not topically administered agmatine could reduce ischemic retinal injury. Transient ocular ischemia was achieved by intraluminal occlusion of the middle cerebral artery of ddY mice (30-35 g) for 2 h, which is known to also induce occlusion of the ophthalmic artery. In the agmatine group (N = 6), a 1.0 mM agmatine-containing ophthalmic solution was administered four times daily for 2 weeks before occlusion. In the control group (N = 6), a 0.1% hyaluronic acid ophthalmic solution was instilled at the same times. At 22 h after reperfusion, the eyeballs were enucleated and the retinal sections were stained by terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL). Transient ocular ischemia induced apoptosis of retinal cells in the entire retinal layer, and topically administered agmatine can significantly reduce this ischemic retinal injury. The proportion of apoptotic cells was definitely decreased (P agmatine application effectively decreases retinal damage in an in vivo ocular ischemic injury model. This implies that agmatine is a good candidate as a direct neuroprotective agent for eyes with ocular ischemic diseases. PMID:22331138

  2. Protection by imidazol(ine) drugs and agmatine of glutamate-induced neurotoxicity in cultured cerebellar granule cells through blockade of NMDA receptor.

    Science.gov (United States)

    Olmos, G; DeGregorio-Rocasolano, N; Paz Regalado, M; Gasull, T; Assumpció Boronat, M; Trullas, R; Villarroel, A; Lerma, J; García-Sevilla, J A

    1999-07-01

    This study was designed to assess the potential neuroprotective effect of several imidazol(ine) drugs and agmatine on glutamate-induced necrosis and on apoptosis induced by low extracellular K+ in cultured cerebellar granule cells. Exposure (30 min) of energy deprived cells to L-glutamate (1-100 microM) caused a concentration-dependent neurotoxicity, as determined 24 h later by a decrease in the ability of the cells to metabolize 3-(4,5-dimethythiazol-2-yl)-2,5-diphenyltetrazoliumbromide (MTT) into a reduced formazan product. L-glutamate-induced neurotoxicity (EC50=5 microM) was blocked by the specific NMDA receptor antagonist MK-801 (dizocilpine). Imidazol(ine) drugs and agmatine fully prevented neurotoxicity induced by 20 microM (EC100) L-glutamate with the rank order (EC50 in microM): antazoline (13)>cirazoline (44)>LSL 61122 [2-styryl-2-imidazoline] (54)>LSL 60101 [2-(2-benzofuranyl) imidazole] (75)>idazoxan (90)>LSL 60129 [2-(1,4-benzodioxan-6-yl)-4,5-dihydroimidazole](101)>RX82 1002 (2-methoxy idazoxan) (106)>agmatine (196). No neuroprotective effect of these drugs was observed in a model of apoptotic neuronal cell death (reduction of extracellular K+) which does not involve stimulation of NMDA receptors. Imidazol(ine) drugs and agmatine fully inhibited [3H]-(+)-MK-801 binding to the phencyclidine site of NMDA receptors in rat brain. The profile of drug potency protecting against L-glutamate neurotoxicity correlated well (r=0.90) with the potency of the same compounds competing against [3H]-(+)-MK-801 binding. In HEK-293 cells transfected to express the NR1-1a and NR2C subunits of the NMDA receptor, antazoline and agmatine produced a voltage- and concentration-dependent block of glutamate-induced currents. Analysis of the voltage dependence of the block was consistent with the presence of a binding site for antazoline located within the NMDA channel pore with an IC50 of 10-12 microM at 0 mV. It is concluded that imidazol(ine) drugs and agmatine are

  3. Agmatine protects rat liver from nicotine-induced hepatic damage via antioxidative, antiapoptotic, and antifibrotic pathways.

    Science.gov (United States)

    El-Sherbeeny, Nagla A; Nader, Manar A; Attia, Ghalia M; Ateyya, Hayam

    2016-12-01

    Tobacco smoking with its various forms is a global problem with proved hazardous effects to human health. The present work was planned to study the defending role of agmatine (AGM) on hepatic oxidative stress and damage induced by nicotine in rats. Thirty-two rats divided into four groups were employed: control group, nicotine-only group, AGM group, and AGM-nicotine group. Measurements of serum hepatic biochemical markers, lipid profile, and vascular cell adhesion molecule-1 were done. In addition, malondialdehyde (MDA), superoxide dismutase (SOD), glutathione (GSH) activity, and nitrate/nitrite (NOx) levels were estimated in the liver homogenates. Immunohistochemistry for Bax and transforming growth factor beta (TGF-β1) and histopathology of the liver were also included. Data of the study demonstrated that nicotine administration exhibited marked liver deterioration, an increase in liver enzymes, changes in lipid profile, and an elevation in MDA with a decline in levels of SOD, GSH, and NOx (nitrate/nitrite). Also, levels of proapoptotic Bax and profibrotic TGF-β1 showed marked elevation in the liver. AGM treatment to rats in nicotine-only group ameliorated all the previous changes. These findings indicate that AGM could successfully overcome the nicotine-evoked hepatic oxidative stress and tissue injury, apoptosis, and fibrosis.

  4. Agmatine attenuates silica-induced pulmonary fibrosis.

    Science.gov (United States)

    El-Agamy, D S; Sharawy, M H; Ammar, E M

    2014-06-01

    There is a large body of evidence that nitric oxide (NO) formation is implicated in mediating silica-induced pulmonary fibrosis. As a reactive free radical, NO may not only contribute to lung parenchymal tissue injury but also has the ability to combine with superoxide and form a highly reactive toxic species peroxynitrite that can induce extensive cellular toxicity in the lung tissues. This study aimed to explore the effect of agmatine, a known NO synthase inhibitor, on silica-induced pulmonary fibrosis in rats. Male Sprague Dawley rats were treated with agmatine for 60 days following a single intranasal instillation of silica suspension (50 mg in 0.1 ml saline/rat). The results revealed that agmatine attenuated silica-induced lung inflammation as it decreased the lung wet/dry weight ratio, protein concentration, and the accumulation of the inflammatory cells in the bronchoalveolar lavage fluid. Agmatine showed antifibrotic activity as it decreased total hydroxyproline content of the lung and reduced silica-mediated lung inflammation and fibrosis in lung histopathological specimen. In addition, agmatine significantly increased superoxide dismutase (p Agmatine also reduced silica-induced overproduction of pulmonary nitrite/nitrate as well as tumor necrosis factor α. Collectively, these results demonstrate the protective effects of agmatine against the silica-induced lung fibrosis that may be attributed to its ability to counteract the NO production, lipid peroxidation, and regulate cytokine effects. © The Author(s) 2014.

  5. Therapeutic potential of agmatine for CNS disorders.

    Science.gov (United States)

    Neis, Vivian B; Rosa, Priscila B; Olescowicz, Gislaine; Rodrigues, Ana Lúcia S

    2017-09-01

    Agmatine is a neuromodulator that regulates multiple neurotransmitters and signaling pathways. Several studies have focused on elucidating the mechanisms underlying the neuroprotective effects of this molecule, which seems to be mediated by a reduction in oxidative damage, neuroinflammation, and proapoptotic signaling. Since these events are implicated in acute and chronic excitotoxicity-related disorders (ischemia, epilepsy, traumatic brain injury, spinal cord injury, neurodegenerative, and psychiatric disorders) as well as in nociception, agmatine has been proposed as a therapeutic strategy for the treatment of central nervous system (CNS) disorders. Agmatine also stimulates the expression of trophic factors and adult neurogenesis, contributing to its ability to induce endogenous repair mechanisms. Therefore, considering its wide range of biological effects, this review summarizes the current knowledge about its protective and regenerative properties in the CNS. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Agmatine in the hypothalamic paraventricular nucleus stimulates feeding in rats: involvement of neuropeptide Y

    Science.gov (United States)

    Taksande, BG; Kotagale, NR; Nakhate, KT; Mali, PD; Kokare, DM; Hirani, K; Subhedar, NK; Chopde, CT; Ugale, RR

    2011-01-01

    BACKGROUND AND PURPOSE Agmatine, a multifaceted neurotransmitter, is abundantly expressed in the hypothalamic paraventricular nucleus (PVN). Our aim was to assess (i) the effect of agmatine on feeding behaviour and (ii) its association, if any, with neuropeptide Y (NPY). EXPERIMENTAL APPROACH Satiated rats fitted with intra-PVN cannulae were administered agmatine, alone or jointly with (i) α2-adrenoceptor agonist, clonidine, or antagonist, yohimbine; (ii) NPY, NPY Y1 receptor agonist, [Leu31, Pro34]-NPY, or antagonist, BIBP3226; or (iii) yohimbine and NPY. Cumulative food intake was monitored at different post-injection time points. Furthermore, the expression of hypothalamic NPY following i.p. treatment with agmatine, alone or in combination with yohimbine (i.p.), was evaluated by immunocytochemistry. KEY RESULTS Agmatine robustly increased feeding in a dose-dependent manner. While pretreatment with clonidine augmented, yohimbine attenuated the orexigenic response to agmatine. Similarly, NPY and [Leu31, Pro34]-NPY potentiated the agmatine-induced hyperphagia, whereas BIBP3226 inhibited it. Moreover, yohimbine attenuated the synergistic orexigenic effect induced by the combination of NPY and agmatine. Agmatine increased NPY immunoreactivity in the PVN fibres and in the cells of the hypothalamic arcuate nucleus (ARC) and this effect was prevented by pretreatment with yohimbine. NPY immunoreactivity in the fibres of the ARC, dorsomedial, ventromedial and lateral nuclei of the hypothalamus was not affected by any of the above treatments. CONCLUSIONS AND IMPLICATIONS The orexigenic effect of agmatine is coupled to increased NPY activity mediated by stimulation of α2-adrenoceptors within the PVN. This signifies the importance of agmatine or α2-adrenoceptor modulators in the development of novel therapeutic agents to treat feeding-related disorders. PMID:21564088

  7. Agmatine reduces extracellular glutamate during pentylenetetrazole-induced seizures in rat brain: A potential mechanism for the anticonvulsive effects

    Science.gov (United States)

    Feng, Yangzheng; LeBlanc, Michael H.; Regunathan, Soundar

    2010-01-01

    Glutamate has been implicated in the initiation and spread of seizure activity. Agmatine, an endogenous neuromodulator, is an antagonist of NMDA receptors and has anticonvulsive effects. Whether agmatine regulate glutamate release, as measured by in vivo microdialysis, is not known. In this study, we used pentylenetetrazole (PTZ)-induced seizure model to determine the effect of agmatine on extracellular glutamate in rat brain. We also determined the time course and the amount of agmatine that reached brain after peripheral injection. After i.p. injection of agmatine (50 mg/kg), increase of agmatine in rat cortex and hippocampus was observed in 15 min with levels returning to baseline in one hour. Rats, naïve and implanted with microdialysis cannula into the cortex, were administered PTZ (60 mg/kg, i.p.) with prior injection of agmatine (100 mg/kg, i.p.) or saline. Seizure grades were recorded and microdialysis samples were collected every 15 min for 75 min. Agmatine pre-treatment significantly reduced the seizure grade and increased the onset time. The levels of extracellular glutamate in frontal cortex rose two- to three-fold after PTZ injection and agmatine significantly inhibited this increase. In conclusion, the present data suggest that the anticonvulsant activity of agmatine, in part, could be related to the inhibition glutamate release. PMID:16125317

  8. Agmatine attenuates methamphetamine-induced hyperlocomotion and stereotyped behavior in mice.

    Science.gov (United States)

    Kitanaka, Nobue; Kitanaka, Junichi; Hall, F Scott; Uhl, George R; Watabe, Kaname; Kubo, Hitoshi; Takahashi, Hitoshi; Tanaka, Koh-ichi; Nishiyama, Nobuyoshi; Takemura, Motohiko

    2014-04-01

    We investigated whether pretreatment with the neurotransmitter/neuromodulator agmatine (decarboxylated L-arginine) affected methamphetamine (METH)-induced hyperlocomotion and stereotypy in male ICR mice. Agmatine pretreatment alone had no effects on locomotion or stereotypy, but it produced a dose-dependent attenuation of locomotion and the total incidence of stereotyped behavior induced by a low dose of METH (5 mg/kg). The stereotypy induced by this dose was predominantly characterized by stereotyped sniffing. By contrast, agmatine did not affect the total incidence of stereotypy induced by a higher dose of METH (10 mg/kg). However, the nature of stereotypy induced by this dose of METH was substantially altered; agmatine pretreatment significantly reduced stereotyped biting but significantly increased stereotyped sniffing and persistent locomotion. Agmatine pretreatment therefore appears to produce a rightward shift in the dose-response curve for METH. Pretreatment of mice with piperazine-1-carboxamidine (a putative agmatinase inhibitor) had no effect on locomotion or stereotypy induced by a low dose of METH, suggesting that endogenous agmatine may not regulate the METH action.

  9. Agmatine Prevents Adaptation of the Hippocampal Glutamate System in Chronic Morphine-Treated Rats.

    Science.gov (United States)

    Wang, Xiao-Fei; Zhao, Tai-Yun; Su, Rui-Bin; Wu, Ning; Li, Jin

    2016-12-01

    Chronic exposure to opioids induces adaptation of glutamate neurotransmission, which plays a crucial role in addiction. Our previous studies revealed that agmatine attenuates opioid addiction and prevents the adaptation of glutamate neurotransmission in the nucleus accumbens of chronic morphine-treated rats. The hippocampus is important for drug addiction; however, whether adaptation of glutamate neurotransmission is modulated by agmatine in the hippocampus remains unknown. Here, we found that continuous pretreatment of rats with ascending doses of morphine for 5 days resulted in an increase in the hippocampal extracellular glutamate level induced by naloxone (2 mg/kg, i.p.) precipitation. Agmatine (20 mg/kg, s.c.) administered concurrently with morphine for 5 days attenuated the elevation of extracellular glutamate levels induced by naloxone precipitation. Furthermore, in the hippocampal synaptosome model, agmatine decreased the release and increased the uptake of glutamate in synaptosomes from chronic morphine-treated rats, which might contribute to the reduced elevation of glutamate levels induced by agmatine. We also found that expression of the hippocampal NR2B subunit, rather than the NR1 subunit, of N-methyl-D-aspartate receptors (NMDARs) was down-regulated after chronic morphine treatment, and agmatine inhibited this reduction. Taken together, agmatine prevented the adaptation of the hippocampal glutamate system caused by chronic exposure to morphine, including modulating extracellular glutamate concentration and NMDAR expression, which might be one of the mechanisms underlying the attenuation of opioid addiction by agmatine.

  10. Neuroprotective effects of agmatine in mice infused with a single intranasal administration of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP).

    Science.gov (United States)

    Matheus, Filipe C; Aguiar, Aderbal S; Castro, Adalberto A; Villarinho, Jardel G; Ferreira, Juliano; Figueiredo, Cláudia P; Walz, Roger; Santos, Adair R S; Tasca, Carla I; Prediger, Rui D S

    2012-12-01

    We have recently demonstrated that rodents treated intranasally with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) suffered impairments in olfactory, cognitive, emotional and motor functions associated with time-dependent disruption of dopaminergic neurotransmission in different brain structures conceivably analogous to those observed during different stages of Parkinson's disease (PD). Agmatine, an endogenous arginine metabolite, has been proposed as a novel neuromodulator that plays protective roles in several models of neuronal cellular damage. In the present study we demonstrated that repeated treatment with agmatine (30 mg/kg, i.p.) during 5 consecutive days increased the survival rate (from 40% to 80%) of 15-month-old C57BL/6 female mice infused with a single intranasal (i.n.) administration of MPTP (1 mg/nostril), improving the general neurological status of the surviving animals. Moreover, pretreatment with agmatine was found to attenuate short-term social memory and locomotor activity impairments observed at different periods after i.n. MPTP administration. These behavioral benefits of exogenous agmatine administration were accompanied by a protection against the MPTP-induced decrease of hippocampal glutamate uptake and loss of dopaminergic neurons in the substantia nigra pars compacta of aging mice, without altering brain monoamine oxidase B (MAO-B) activity. These results provide new insights in experimental models of PD, indicating that agmatine represents a potential therapeutic tool for the management of cognitive and motor symptoms of PD, together with its neuroprotective effects. Copyright © 2012 Elsevier B.V. All rights reserved.

  11. Agmatine protects against intracerebroventricular streptozotocin-induced water maze memory deficit, hippocampal apoptosis and Akt/GSK3β signaling disruption.

    Science.gov (United States)

    Moosavi, Maryam; Zarifkar, Amir Hossein; Farbood, Yaghoub; Dianat, Mahin; Sarkaki, Alireza; Ghasemi, Rasoul

    2014-08-05

    Centrally administered streptozotocin (STZ), is known to cause Alzheimer׳s like memory deterioration. It mainly affects insulin signaling pathways such as PI3/Akt and GSK-3β which are involved in cell survival. Previous studies indicate that STZ increases the ratio of Bax/Bcl-2 and thereby induces caspase-3 activation and apoptosis. Agmatine, a polyamine derived from l-arginine decarboxylation, is recently shown to exert some neuroprotective effects. This study aimed to assess if agmatine reverses STZ-induced memory deficits, hippocampal Akt/GSK-3β signaling disruption and caspase-3 activation. Adult male Sprague-Dawely rats weighing 200-250 g were used. The canules were implanted bilaterally into lateral ventricles. STZ was administered on days 1 and 3 (3 mg/kg) and agmatine treatment (40 or 80 mg/kg) was started from day 4 and continued in an every other day manner till day 14. The animal׳s learning and memory capability was assessed on days 15-18 using Morris water maze. After complement of behavioral studies the hippocampi was isolated and the amounts of hippocampal cleaved caspase-3 (the landmark of apoptosis), Bax/Bcl-2 ratio, total and phosphorylated forms of GSK-3β and Akt were analyzed by western blot. The results showed that agmatine in 80 but not 40 mg/kg reversed the memory deterioration induced by STZ. Western blot analysis revealed that STZ prompted elevation of caspase-3; Bax/Bcl-2 ratio and disrupted Akt/GSK-3β signaling in the hippocampus. Agmatine treatment prevented apoptosis and Akt/GSK-3β signaling impairment induced by STZ. This study disclosed that agmatine treatment averts not only STZ-induced memory deterioration but also hippocampal apoptosis and Akt/GSK-3β signaling disruption. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Evidences for the agmatine involvement in antidepressant like effect of bupropion in mouse forced swim test.

    Science.gov (United States)

    Kotagale, Nandkishor R; Tripathi, Sunil J; Aglawe, Manish M; Chopde, Chandrabhan T; Umekar, Milind J; Taksande, Brijesh G

    2013-06-01

    Although bupropion has been widely used in the treatment of depression, the precise mechanism of its therapeutic actions is not fully understood. The present study investigated the role of agmatine in an antidepressant like effect of bupropion in mouse forced swim test. The antidepressant like effect of bupropion was potentiated by pretreatment with agmatine (10-20mg/kg, ip) and by the drugs known to increase endogenous agmatine levels in brain viz., l-arginine (40 μg/mouse, icv), an agmatine biosynthetic precursor, ornithine decarboxylase inhibitor, dl-α-difluoromethyl ornithine hydrochloride, DFMO (12.5 μg/mouse, icv), diamine oxidase inhibitor, aminoguanidine (6.5 μg/mouse, icv) and agmatinase inhibitor, arcaine (50 μg/mouse, icv) as well as imidazoline I1 receptor agonists, moxonidine (0.25mg/kg, ip) and clonidine (0.015 mg/kg, ip) and imidazoline I2 receptor agonist, 2-(2-benzofuranyl)-2-imidazoline hydrochloride, 2-BFI (5mg/kg, ip). Conversely, prior administration of I1 receptor antagonist, efaroxan (1mg/kg, ip) and I2 receptor antagonist, idazoxan (0.25mg/kg, ip) blocked the antidepressant like effect of bupropion and its synergistic combination with agmatine. These results demonstrate involvement of agmatine in the antidepressant like effect of bupropion and suggest agmatine and imidazoline receptors as a potential therapeutic target for the treatment of depressive disorders. Copyright © 2013 Elsevier Inc. All rights reserved.

  13. Agmatine Ameliorates High Glucose-Induced Neuronal Cell Senescence by Regulating the p21 and p53 Signaling.

    Science.gov (United States)

    Song, Juhyun; Lee, Byeori; Kang, Somang; Oh, Yumi; Kim, Eosu; Kim, Chul-Hoon; Song, Ho-Taek; Lee, Jong Eun

    2016-02-01

    Neuronal senescence caused by diabetic neuropathy is considered a common complication of diabetes mellitus. Neuronal senescence leads to the secretion of pro-inflammatory cytokines, the production of reactive oxygen species, and the alteration of cellular homeostasis. Agmatine, which is biosynthesized by arginine decarboxylation, has been reported in previous in vitro to exert a protective effect against various stresses. In present study, agmatine attenuated the cell death and the expression of pro-inflammatory cytokines such as IL-6, TNF-alpha and CCL2 in high glucose in vitro conditions. Moreover, the senescence associated-β-galatosidase's activity in high glucose exposed neuronal cells was reduced by agmatine. Increased p21 and reduced p53 in high glucose conditioned cells were changed by agmatine. Ultimately, agmatine inhibits the neuronal cell senescence through the activation of p53 and the inhibition of p21. Here, we propose that agmatine may ameliorate neuronal cell senescence in hyperglycemia.

  14. Anti-Atherosclerotic Action of Agmatine in ApoE-Knockout Mice.

    Science.gov (United States)

    Wiśniewska, Anna; Olszanecki, Rafał; Totoń-Żurańska, Justyna; Kuś, Katarzyna; Stachowicz, Aneta; Suski, Maciej; Gębska, Anna; Gajda, Mariusz; Jawień, Jacek; Korbut, Ryszard

    2017-08-04

    Atherosclerosis is an inflammatory disease in which dysfunction of mitochondria play an important role, and disorders of lipid management intensify this process. Agmatine, an endogenous polyamine formed by decarboxylation of arginine, exerts a protective effect on mitochondria and modulates fatty acid metabolism. We investigated the effect of exogenous agmatine on the development of atherosclerosis and changes in lipid profile in apolipoprotein E knockout (apoE-/-) mice. Agmatine caused an approximate 40% decrease of atherosclerotic lesions, as estimated by en face and cross-section methods with an influence on macrophage but not on smooth muscle content in the plaques. Agmatine treatment did not changed gelatinase activity within the plaque area. What is more, the action of agmatine was associated with an increase in the number of high density lipoproteins (HDL) in blood. Real-Time PCR analysis showed that agmatine modulates liver mRNA levels of many factors involved in oxidation of fatty acid and cholesterol biosynthesis. Two-dimensional electrophoresis coupled with mass spectrometry identified 27 differentially expressed mitochondrial proteins upon agmatine treatment in the liver of apoE-/- mice, mostly proteins related to metabolism and apoptosis. In conclusion, prolonged administration of agmatine inhibits atherosclerosis in apoE-/- mice; however, the exact mechanisms linking observed changes and elevations of HDL plasma require further investigation.

  15. Phospholipase C-dependent hydrolysis of phosphatidylinositol 4,5-bisphosphate underlies agmatine-induced suppression of N-type Ca2+ channel in rat celiac ganglion neurons.

    Science.gov (United States)

    Kim, Young-Hwan; Jeong, Ji-Hyun; Ahn, Duck-Sun; Chung, Seungsoo

    2017-03-04

    Agmatine suppresses peripheral sympathetic tone by modulating Cav2.2 channels in peripheral sympathetic neurons. However, the detailed cellular signaling mechanism underlying the agmatine-induced Cav2.2 inhibition remains unclear. Therefore, in the present study, we investigated the electrophysiological mechanism for the agmatine-induced inhibition of Cav2.2 current (I Cav2.2 ) in rat celiac ganglion (CG) neurons. Consistent with previous reports, agmatine inhibited I Cav2.2 in a VI manner. The agmatine-induced inhibition of the I Cav2.2 current was also almost completely hindered by the blockade of the imidazoline I 2 receptor (IR 2 ), and an IR 2 agonist mimicked the inhibitory effect of agmatine on I Cav2.2 , implying involvement of IR 2 . The agmatine-induced I Cav2.2 inhibition was significantly hampered by the blockade of G protein or phospholipase C (PLC), but not by the pretreatment with pertussis toxin. In addition, diC8-phosphatidylinositol 4,5-bisphosphate (PIP 2 ) dialysis nearly completely hampered agmatine-induced inhibition, which became irreversible when PIP 2 resynthesis was blocked. These results suggest that in rat peripheral sympathetic neurons, agmatine-induced IR 2 activation suppresses Cav2.2 channel voltage-independently, and that the PLC-dependent PIP 2 hydrolysis is responsible for the agmatine-induced suppression of the Cav2.2 channel. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Creatine pretreatment protects cortical axons from energy depletion in vitro

    Science.gov (United States)

    Shen, Hua; Goldberg, Mark P.

    2012-01-01

    Creatine is a natural nitrogenous guanidino compound involved in bioenergy metabolism. Although creatine has been shown to protect neurons of the central nervous system (CNS) from experimental hypoxia/ischemia, it remains unclear if creatine may also protect CNS axons, and if the potential axonal protection depends on glial cells. To evaluate the direct impact of creatine on CNS axons, cortical axons were cultured in a separate compartment from their somas and proximal neurites using a modified two-compartment culture device. Axons in the axon compartment were subjected to acute energy depletion, an in vitro model of white matter ischemia, by exposure to 6 mM sodium azide for 30 min in the absence of glucose and pyruvate. Energy depletion reduced axonal ATP by 65%, depolarized axonal resting potential, and damaged 75% of axons. Application of creatine (10 mM) to both compartments of the culture at 24 h prior to energy depletion significantly reduced axonal damage by 50%. In line with the role of creatine in the bioenergy metabolism, this application also alleviated the axonal ATP loss and depolarization. Inhibition of axonal depolarization by blocking sodium influx with tetrodotoxin also effectively reduced the axonal damage caused by energy depletion. Further study revealed that the creatine effect was independent of glial cells, as axonal protection was sustained even when creatine was applied only to the axon compartment (free from somas and glial cells) for as little as 2 h. In contrast, application of creatine after energy depletion did not protect axons. The data provide the first evidence that creatine pretreatment may directly protect CNS axons from energy deficiency. PMID:22521466

  17. Development of a Pseudomonas aeruginosa Agmatine Biosensor

    OpenAIRE

    Gilbertsen, Adam; Williams, Bryan

    2014-01-01

    Agmatine, decarboxylated arginine, is an important intermediary in polyamine production for many prokaryotes, but serves higher functions in eukaryotes such as nitric oxide inhibition and roles in neurotransmission. Pseudomonas aeruginosa relies on the arginine decarboxylase and agmatine deiminase pathways to convert arginine into putrescine. One of the two known agmatine deiminase operons, aguBA, contains an agmatine sensitive TetR promoter controlled by AguR. We have discovered that this pr...

  18. Agmatine ameliorates atherosclerosis progression and endothelial dysfunction in high cholesterol-fed rabbits.

    Science.gov (United States)

    El-Awady, Mohammed S; Suddek, Ghada M

    2014-06-01

    The aim of this work was to explore possible effects of agmatine, an endogenous inhibitor of inducible nitric oxide synthase (iNOS), against hypercholesterolemia-induced lipid profile changes and endothelial dysfunction. Hypercholesterolemia was induced by feeding rabbits with a high-cholesterol diet (HCD, 0.5%) for 8 weeks. Another HCD-fed group was orally administered agmatine (10 mg/kg/day) during weeks 5 through 8. Serum lipid profile, malondialdehyde (MDA), nitric oxide (NO) and lactate dehydrogenase (LDH) were determined. Aorta was isolated to analyse vascular reactivity, atherosclerotic lesions and intima/media (I/M) ratio. HCD induced a significant increase in serum total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), triglycerides and high-density lipoprotein cholesterol (HDL-C). Agmatine administration significantly decreased HCD-induced elevations in serum TC and LDL-C, MDA, LDH and NO while significantly increased HDL-C levels. Additionally, agmatine significantly protected against HCD-induced attenuation of rabbit aortic endothelium-dependent relaxation to acetylcholine. HCD and agmatine did not significantly influence aortic endothelium-independent relaxation to sodium nitroprusside. Moreover, agmatine significantly reduced the elevation in aortic atherosclerotic lesion area and I/M ratio. This study is the first to reveal that agmatine has the ability to ameliorate hypercholesterolemia-induced lipemic-oxidative and endothelial function injuries possibly by its antioxidant potential and/or iNOS inhibition. © 2014 Royal Pharmaceutical Society.

  19. Agmatine attenuates the discriminative stimulus and hyperthermic effects of methamphetamine in male rats.

    Science.gov (United States)

    Thorn, David A; Li, Jiuzhou; Qiu, Yanyan; Li, Jun-Xu

    2016-09-01

    Methamphetamine abuse remains an alarming public heath challenge, with no approved pharmacotherapies available. Agmatine is a naturally occurring cationic polyamine that has previously been shown to attenuate the rewarding and psychomotor-sensitizing effects of methamphetamine. This study examined the effects of agmatine on the discriminative stimulus and hyperthermic effects of methamphetamine. Adult male rats were trained to discriminate 0.32 mg/kg methamphetamine from saline. Methamphetamine dose dependently increased drug-associated lever responding. The nonselective dopamine receptor antagonist haloperidol (0.1 mg/kg) significantly attenuated the discriminative stimulus effects of methamphetamine (5.9-fold rightward shift). Agmatine (10-100 mg/kg) did not substitute for methamphetamine, but significantly attenuated the stimulus effects of methamphetamine, leading to a maximum of a 3.5-fold rightward shift. Acute 10 mg/kg methamphetamine increased the rectal temperature by a maximum of 1.96±0.17°C. Agmatine (10-32 mg/kg) pretreatment significantly attenuated the hyperthermic effect of methamphetamine. Agmatine (10 mg/kg) also significantly reversed methamphetamine-induced temperature increase. Together, these results support further exploration of the value that agmatine may have for the treatment of methamphetamine abuse and overdose.

  20. Agmatine attenuates nicotine induced conditioned place preference in mice through modulation of neuropeptide Y system.

    Science.gov (United States)

    Kotagale, Nandkishor R; Walke, Sonali; Shelkar, Gajanan P; Kokare, Dadasaheb M; Umekar, Milind J; Taksande, Brijesh G

    2014-04-01

    The purpose of the present study was to examine the effect of agmatine on nicotine induced conditioned place preference (CPP) in male albino mice. Intra-peritoneal (ip) administration of nicotine (1mg/kg) significantly increased time spent in drug-paired compartment. Agmatine (20 and 40 mg/kg, ip) co-administered with nicotine during the 6 days conditioning sessions completely abolished the acquisition of nicotine-induced CPP in mice. Concomitant administration of neuropeptide Y (NPY) (1 pg/mouse, icv) or [Leu(31), Pro(34)]-NPY (0.1 pg/mouse, icv), selective NPY Y1 receptor agonist potentiated the inhibitory effect of agmatine (10 mg/kg, ip) on nicotine CPP. Conversely, pretreatment with NPY Y1 receptor antagonist, BIBP3226 (0.01 ng/mouse, icv) blocked the effect of agmatine (20 mg/kg, ip) on nicotine induced CPP. In immunohistochemical study, nicotine decreased NPY-immunoreactivity in nucleus accumbens shell (AcbSh), bed nucleus of stria terminalis, lateral part (BNSTl), arcuate nucleus (ARC) and paraventricular nucleus (PVN). Conversely, administration of agmatine prior to the nicotine significantly reversed the effect of nicotine on NPY-immunoreactivity in the above brain nuclei. This data indicate that agmatine attenuate nicotine induced CPP via modulation of NPYergic neurotransmission in brain. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Environmentally friendly hybrid coatings for corrosion protection: silane based pre-treatments and nanostructured waterborne coatings

    OpenAIRE

    Fedel, Michele

    2009-01-01

    This thesis considers a nanotechnology approach based on the production of metals pre-treatments and organic coatings (a complete protection system at all) designed from the nanoscale. The final aim is to develop protection systems with improved corrosion protection properties and a low environmental impact. In particular, multifunctional silane hybrid molecules were used to design sol-gel pre-treatments for metals and to modify the inner structure of UV curable waterborne organic coatings...

  2. Neuropeptide Y in the central nucleus of amygdala regulates the anxiolytic effect of agmatine in rats.

    Science.gov (United States)

    Taksande, Brijesh G; Kotagale, Nandkishor R; Gawande, Dinesh Y; Bharne, Ashish P; Chopde, Chandrabhan T; Kokare, Dadasaheb M

    2014-06-01

    In the present study, modulation of anxiolytic action of agmatine by neuropeptide Y (NPY) in the central nucleus of amygdala (CeA) is evaluated employing Vogel's conflict test (VCT) in rats. The intra-CeA administration of agmatine (0.6 and 1.2µmol/rat), NPY (10 and 20pmol/rat) or NPY Y1/Y5 receptors agonist [Leu(31), Pro(34)]-NPY (30 and 60pmol/rat) significantly increased the number of punished drinking licks following 15min of treatment. Combination treatment of subeffective dose of NPY (5pmol/rat) or [Leu(31), Pro(34)]-NPY (15pmol/rat) and agmatine (0.3µmol/rat) produced synergistic anxiolytic-like effect. However, intra-CeA administration of selective NPY Y1 receptor antagonist, BIBP3226 (0.25 and 0.5mmol/rat) produced anxiogenic effect. In separate set of experiment, pretreatment with BIBP3226 (0.12mmol/rat) reversed the anxiolytic effect of agmatine (0.6µmol/rat). Furthermore, we evaluated the effect of intraperitoneal injection of agmatine (40mg/kg) on NPY-immunoreactivity in the nucleus accumbens shell (AcbSh), lateral part of bed nucleus of stria terminalis (BNSTl) and CeA. While agmatine treatment significantly decreased the fibers density in BNSTl, increase was noticed in AcbSh. In addition, agmatine reduced NPY-immunoreactive cells in the AcbSh and CeA. Immunohistochemical data suggest the enhanced transmission of NPY from the AcbSh and CeA. Taken together, this study suggests that agmatine produced anxiolytic effect which might be regulated via modulation of NPYergic system particularly in the CeA. Copyright © 2013 Elsevier B.V. and ECNP. All rights reserved.

  3. Possible involvement of neuropeptide Y Y1 receptors in antidepressant like effect of agmatine in rats.

    Science.gov (United States)

    Kotagale, Nandkishor R; Paliwal, Nikhilesh P; Aglawe, Manish M; Umekar, Milind J; Taksande, Brijesh G

    2013-09-01

    Agmatine and neuropeptide Y (NPY) are widely distributed in central nervous system and critically involved in modulation of depressive behavior in experimental animals. However their mutual interaction, if any, in regulation of depression remain largely unexplored. In the present study we explored the possible interaction between agmatine and neuropeptide Y in regulation of depression like behavior in forced swim test. We found that acute intracerebroventricular (i.c.v.) administration of agmatine (20-40μg/rat), NPY (5 and 10μg/rat) and NPY Y1 receptor agonist, [Leu(31), Pro(34)]-NPY (0.4 and 0.8ng/rat) dose dependently decreased immobility time in forced swim test indicating their antidepressant like effects. In combination studies, the antidepressant like effect of agmatine (10μg/rat) was significantly potentiated by NPY (1 and 5μg/rat, icv) or [Leu(31), Pro(34)]-NPY (0.2 and 0.4ng/rat, icv) pretreatment. Conversely, pretreatment of animals with NPY Y1 receptor antagonist, BIBP3226 (0.1ng/rat, i.c.v.) completely blocked the antidepressant like effect of agmatine (20-40μg/rat) and its synergistic effect with NPY (1μg/rat, icv) or [Leu(31), Pro(34)]-NPY (0.2ng/rat, icv). The results of the present study showed that, agmatine exerts antidepressant like effects via NPYergic system possibly mediated by the NPY Y1 receptor subtypes and suggest that interaction between agmatine and neuropeptide Y may be relevant to generate the therapeutic strategies for the treatment of depression. Copyright © 2013 Elsevier Inc. All rights reserved.

  4. Agmatine modulates melanogenesis via MITF signaling pathway.

    Science.gov (United States)

    Kwon, Eun-Jeong; Kim, Moon-Moo

    2017-01-01

    Agmatine contained in soybean is also found in Manaca, an anti-aging plant, inhabited in Amazon and induces vasodilation by the promotion of NO synthesis in blood vessel. However, the research of agmatine on melanin synthesis related to hair greying is lacking. The aim of this study was to investigate the melanogenic effect of agmatine via regulation of MITF signaling pathway in B16F1 cells. It was determined whether agmatine regulates melanin synthesis at cellular level in addition to the effect of agmatine on mushroom tyrosinase in vitro in the presence of different concentrations of agmatine. Furthermore, the effect of agmatine on the protein expressions of tyrosinase, TRP-1, TRP-2, BMP-4, BMP-6, C-KIT, p-p38, MITF and C-FOS were examined by western blot analysis. In addition, immunofluorescence staining was carried out to visualize the location of MITF expression in cell. Agmatine at 256μM or more increased melanin synthesis as well as tyrosinase activity. Moreover, whereas agmatine increased the expression levels of TRP-1, BMP-6, p-p38 and MITF, it reduced the expression level of BMP-4. It was also found that agmatine enhanced the expression level of MITF in nucleus. These results suggest that agmatine could induce melanin synthesis though the regulation of MITF transcription factor via BMP-6/p38 signaling pathway. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Development of a Pseudomonas aeruginosa Agmatine Biosensor

    Directory of Open Access Journals (Sweden)

    Adam Gilbertsen

    2014-10-01

    Full Text Available Agmatine, decarboxylated arginine, is an important intermediary in polyamine production for many prokaryotes, but serves higher functions in eukaryotes such as nitric oxide inhibition and roles in neurotransmission. Pseudomonas aeruginosa relies on the arginine decarboxylase and agmatine deiminase pathways to convert arginine into putrescine. One of the two known agmatine deiminase operons, aguBA, contains an agmatine sensitive TetR promoter controlled by AguR. We have discovered that this promoter element can produce a titratable induction of its gene products in response to agmatine, and utilized this discovery to make a luminescent agmatine biosensor in P. aeruginosa. The genome of the P. aeruginosa lab strain UCBPP-PA14 was altered to remove both its ability to synthesize or destroy agmatine, and insertion of the luminescent reporter construct allows it to produce light in proportion to the amount of exogenous agmatine applied from ~100 nM to 1mM. Furthermore it does not respond to related compounds including arginine or putrescine. To demonstrate potential applications the biosensor was used to detect agmatine in spent supernatants, to monitor the development of arginine decarboxylase over time, and to detect agmatine in the spinal cords of live mice.

  6. Agmatine, by Improving Neuroplasticity Markers and Inducing Nrf2, Prevents Corticosterone-Induced Depressive-Like Behavior in Mice.

    Science.gov (United States)

    Freitas, Andiara E; Egea, Javier; Buendia, Izaskun; Gómez-Rangel, Vanessa; Parada, Esther; Navarro, Elisa; Casas, Ana Isabel; Wojnicz, Aneta; Ortiz, José Avendaño; Cuadrado, Antonio; Ruiz-Nuño, Ana; Rodrigues, Ana Lúcia S; Lopez, Manuela G

    2016-07-01

    Agmatine, an endogenous neuromodulator, is a potential candidate to constitute an adjuvant/monotherapy for the management of depression. A recent study by our group demonstrated that agmatine induces Nrf2 and protects against corticosterone effects in a hippocampal neuronal cell line. The present study is an extension of this previous study by assessing the antidepressant-like effect of agmatine in an animal model of depression induced by corticosterone in mice. Swiss mice were treated simultaneously with agmatine or imipramine at a dose of 0.1 mg/kg/day (p.o.) and corticosterone for 21 days and the daily administrations of experimental drugs were given immediately prior to corticosterone (20 mg/kg/day, p.o.) administrations. Wild-type C57BL/6 mice (Nrf2 (+/+)) and Nrf2 KO (Nrf2 (-/-)) were treated during 21 days with agmatine (0.1 mg/kg/day, p.o.) or vehicle. Twenty-four hours after the last treatments, the behavioral tests and biochemical assays were performed. Agmatine treatment for 21 days was able to abolish the corticosterone-induced depressive-like behavior and the alterations in the immunocontent of mature BDNF and synaptotagmin I, and in the serotonin and glutamate levels. Agmatine also abolished the corticosterone-induced changes in the morphology of astrocytes and microglia in CA1 region of hippocampus. In addition, agmatine treatment in control mice increased noradrenaline, serotonin, and dopamine levels, CREB phosphorylation, mature BDNF and synaptotagmin I immunocontents, and reduced pro-BDNF immunocontent in the hippocampus. Agmatine's ability to produce an antidepressant-like effect was abolished in Nrf2 (-/-) mice. The present results reinforce the participation of Nrf2 in the antidepressant-like effect produced by agmatine and expand literature data concerning its mechanisms of action.

  7. Agmatine ameliorates lipopolysaccharide induced depressive-like behaviour in mice by targeting the underlying inflammatory and oxido-nitrosative mediators.

    Science.gov (United States)

    Gawali, Nitin B; Bulani, Vipin D; Chowdhury, Amrita A; Deshpande, Padmini S; Nagmoti, Dnyaneshwar M; Juvekar, Archana R

    2016-10-01

    Experimental and clinical evidence indicates that pro-inflammatory cytokines, oxidative stress and brain-derived neurotrophic factor (BDNF) signalling mechanisms play a role in the pathophysiology of depression. Agmatine is a neurotransmitter and/or neuromodulator that has emerged as a potential agent to manage diverse central nervous system disorders. Agmatine has been shown to exert antidepressant-like effect. The present study investigated ability of agmatine to abolish the depressive-like behaviour induced by the administration of the lipopolysaccharide (LPS) in mice. Agmatine (20 and 40mg/kg) was administered daily for 7days, then the mice were challenged with saline or LPS (0.83mg/kg; i.p.) on the 7th day. After 24h of LPS administration we tested mice for depressive-like behaviour. LPS treated animals presented an increase in immobility time in the forced-swim test (FST), tail suspension test (TST) which was reversed by agmatine pre-treatment (20 and 40mg/kg). Oxidative/nitrosative stress evoked by LPS was ameliorated by both doses of agmatine in hippocampus (HC) and prefrontal cortex (PFC). Administration of LPS caused an increase in interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α), whereas BDNF was down regulated in the HC. Agmatine pre-treatment at 40mg/kg ameliorated LPS-induced neuroinflammation by attenuating brain IL-1β and TNF-α level. In addition, agmatine pre-treatment also up-regulated the BDNF level in the HC. The present study shows that pre-treatment of agmatine is able to abolish the behavioural responses in the FST and TST elicited by the LPS-induced model of depression that may depend on the inhibition of pro-inflammatory mediators, reduction of oxidative stress as well as activation neuroplasticity-related signalling in mice, suggesting that agmatine may constitute an monotherapy/adjuvant for the management of depression associated with inflammation. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. [Protective effect of Uncaria rhynchophylla total alkaloids pretreatment on hippocampal neurons after acute hypoxia].

    Science.gov (United States)

    Liu, Wei; Zhang, Zhao-qin; Zhao, Xiao-min; Gao, Yun-sheng

    2006-05-01

    To investigate the effect of Uncaria rhynchophylla total alkaloids (RTA) pretreatment on the voltage-gated sodium currents of the rat hippocampal neurons after acute hypoxia. Primary cultured hippocampal neurons were divided into RTA pre-treated and non-pretreated groups. Patch clamp whole-cell recording was used to compare the voltage-gated sodium current amplitude and threshold with those before hypoxia. After acute hypoxia, sodium current amplitude was significantly decreased and its threshold was upside. RTA pretreatment could inhibit the reduction of sodium current amplitude. RTA pretreatment alleviates the acute hypoxia-induced change of sodium currents, which may be one of the mechanisms for protective effect of RTA on cells.

  9. Agmatine improves renal function in gentamicin-induced nephrotoxicity in rats.

    Science.gov (United States)

    El-Kashef, Dalia H; El-Kenawi, Asmaa E; Abdel Rahim, Mona; Suddek, Ghada M; Salem, Hatem A

    2016-03-01

    The present study was designed to explore the possible protective effects of agmatine, a known nitric oxide (NO) synthase inhibitor, against gentamicin-induced nephrotoxicity in rats. For this purpose, we quantitatively evaluated gentamicin-induced renal structural and functional alterations using histopathological and biochemical approaches. Furthermore, the effect of agmatine on gentamicin-induced hypersensitivity of urinary bladder rings to acetylcholine (ACh) was evaluated. Twenty-four male Wistar albino rats were randomly divided into 3 groups, namely control, gentamicin (100 mg/kg, i.p.), and gentamicin plus agmatine (40 mg/kg, orally). At the end of the study, all rats were sacrificed and then blood and urine samples and kidneys were taken. Administration of agmatine significantly decreased kidney/body mass ratio, serum creatinine, lactate dehydrogenase (LDH), renal malondialdehyde (MDA), myeloperoxidase (MPO), NO, and tumor necrosis factor-alpha (TNF-α) while it significantly increased creatinine clearance and renal superoxide dismutase (SOD) activity when compared with the gentamicin-treated group. Additionally, agmatine ameliorated tissue morphology as evidenced by histological evaluation and reduced the responses of isolated bladder rings to ACh. Our study indicates that agmatine administration with gentamicin attenuates oxidative-stress associated renal injury by reducing oxygen free radicals and lipid peroxidation, restoring NO level and inhibiting inflammatory mediators such as TNF-α.

  10. Effects of Agmatine on Depressive-Like Behavior Induced by Intracerebroventricular Administration of 1-Methyl-4-phenylpyridinium (MPP(+)).

    Science.gov (United States)

    Moretti, Morgana; Neis, Vivian Binder; Matheus, Filipe Carvalho; Cunha, Mauricio Peña; Rosa, Priscila Batista; Ribeiro, Camille Mertins; Rodrigues, Ana Lúcia S; Prediger, Rui Daniel

    2015-10-01

    Considering that depression is a common non-motor comorbidity of Parkinson's disease and that agmatine is an endogenous neuromodulator that emerges as a potential agent to manage diverse central nervous system disorders, this study investigated the antidepressant-like effect of agmatine in mice intracerebroventricularly (i.c.v.) injected with the dopaminergic neurotoxin 1-methyl-4-phenylpyridinium (MPP(+)). Male C57BL6 mice were treated with agmatine (0.0001, 0.1 or 1 mg/kg) and 60 min later the animals received an i.c.v. injection of MPP(+) (1.8 µg/site). Twenty-four hours after MPP(+) administration, immobility time, anhedonic behavior, and locomotor activity were evaluated in the tail suspension test (TST), splash test, and open field test, respectively. Using Western blot analysis, we investigated the putative modulation of MPP(+) and agmatine on striatal and frontal cortex levels of tyrosine hydroxylase (TH) and brain-derived neurotrophic factor (BDNF). MPP(+) increased the immobility time of mice in the TST, as well as induced an anhedonic-like behavior in the splash test, effects which were prevented by pre-treatment with agmatine at the three tested doses. Neither drug, alone or in combination, altered the locomotor activity of mice. I.c.v. administration of MPP(+) increased the striatal immunocontent of TH, an effect prevented by the three tested doses of agmatine. MPP(+) and agmatine did not alter the immunocontent of BDNF in striatum and frontal cortex. These results demonstrate for the first time the antidepressant-like effects of agmatine in an animal model of depressive-like behavior induced by the dopaminergic neurotoxin MPP(+).

  11. Suppression of MicroRNA let-7a Expression by Agmatine Regulates Neural Stem Cell Differentiation.

    Science.gov (United States)

    Song, Juhyun; Oh, Yumi; Kim, Jong Youl; Cho, Kyoung Joo; Lee, Jong Eun

    2016-11-01

    Neural stem cells (NSCs) effectively reverse some severe central nervous system (CNS) disorders, due to their ability to differentiate into neurons. Agmatine, a biogenic amine, has cellular protective effects and contributes to cellular proliferation and differentiation in the CNS. Recent studies have elucidated the function of microRNA let-7a (let-7a) as a regulator of cell differentiation with roles in regulating genes associated with CNS neurogenesis. This study aimed to investigate whether agmatine modulates the expression of crucial regulators of NSC differentiation including DCX, TLX, c-Myc, and ERK by controlling let-7a expression. Our data suggest that high levels of let-7a promoted the expression of TLX and c-Myc, as well as repressed DCX and ERK expression. In addition, agmatine attenuated expression of TLX and increased expression of ERK by negatively regulating let-7a. Our study therefore enhances the present understanding of the therapeutic potential of NSCs in CNS disorders.

  12. Effect of agmatine on locus coeruleus neuron activity: possible involvement of nitric oxide

    Science.gov (United States)

    Ruiz-Durántez, Eduardo; Ruiz-Ortega, José A; Pineda, Joseba; Ugedo, Luisa

    2002-01-01

    To investigate whether agmatine (the proposed endogenous ligand for imidazoline receptors) controls locus coeruleus neuron activity and to elucidate its mechanism of action, we used single-unit extracellular recording techniques in anaesthetized rats. Agmatine (10, 20 and 40 μg, i.c.v.) increased in a dose-related manner the firing rate of locus coeruleus neurons (maximal increase: 95±13% at 40 μg). I1-imidazoline receptor ligands stimulate locus coeruleus neuron activity through an indirect mechanism originated in the paragigantocellularis nucleus via excitatory amino acids. However, neither electrolytic lesions of the paragigantocellularis nucleus nor pretreatment with the excitatory amino acid antagonist kynurenic acid (1 μmol, i.c.v.) modified agmatine effect (10 μg, i.c.v.). After agmatine administration (20 μg, i.c.v.), dose-response curves for the effect of clonidine (0.625 – 10 μg kg−1 i.v.) or morphine (0.3 – 4.8 mg kg−1 i.v.) on locus coeruleus neurons were not different from those obtained in the control groups. Pretreatment with the nitric oxide synthase inhibitors Nω-nitro-L-arginine (10 μg, i.c.v.) or Nω-nitro-L-arginine methyl ester (100 μg, i.c.v.) but not with the less active stereoisomer Nω-nitro-D-arginine methyl ester (100 μg, i.c.v.) completely blocked agmatine effect (10 and 40 μg, i.c.v.). Similarly, when agmatine (20 pmoles) was applied into the locus coeruleus there was an increase that was blocked by Nω-nitro-L-arginine methyl ester (100 μg, i.c.v.) in the firing rate of the locus coeruleus neurons (maximal increase 53±11% and 14±10% before and after nitric oxide synthase inhibition, respectively). This study demonstrates that agmatine stimulates the firing rate of locus coeruleus neurons via a nitric oxide synthase-dependent mechanism located in this nucleus. PMID:11877321

  13. Hypoxic pretreatment protects against neuronal damage of the rat hippocampus induced by severe hypoxia.

    Science.gov (United States)

    Gorgias, N; Maidatsi, P; Tsolaki, M; Alvanou, A; Kiriazis, G; Kaidoglou, K; Giala, M

    1996-04-01

    The present study investigates whether under conditions of successive hypoxic exposures pretreatment with mild (15% O(2)) or moderate (10% O(2)) hypoxia, protects hippocampal neurones against damage induced by severe (3% O(2)) hypoxia. The ultrastructural findings were also correlated with regional superoxide dismutase (SOD) activity changes. In unpretreated rats severe hypoxia induced ultrastructural changes consistent with the aspects of delayed neuronal death (DND). However, in preexposed animals hippocampal damage was attenuated in an inversely proportional way with the severity of the hypoxic pretreatment. The ultrastructural hypoxic tolerance findings were also closely related to increased regional SOD activity levels. Thus the activation of the endogenous antioxidant defense by hypoxic preconditioning, protects against hippocampal damage induced by severe hypoxia. The eventual contribution of increased endogenous adenosine and/or reduced excitotoxicity to induce hypoxic tolerance is discussed.

  14. Agmatine enhances the antidepressant-like effect of lithium in mouse forced swimming test through NMDA pathway.

    Science.gov (United States)

    Mohseni, Gholmreza; Ostadhadi, Sattar; Imran-Khan, Muhammad; Norouzi-Javidan, Abbas; Zolfaghari, Samira; Haddadi, Nazgol-Sadat; Dehpour, Ahmad-Reza

    2017-04-01

    Depression is one the world leading global burdens leading to various comorbidities. Lithium as a mainstay in the treatment of depression is still considered gold standard treatment. Similar to lithium another agent agmatine has also central protective role against depression. Since, both agmatine and lithium modulate various effects through interaction with NMDA receptor, therefore, in current study we aimed to investigate the synergistic antidepressant-like effect of agmatine with lithium in mouse force swimming test. Also to know whether if such effect is due to interaction with NMDA receptor. In our present study we found that when potent dose of lithium (30mg/kg) was administered, it significantly decreased the immobility time. Also, when subeffective dose of agmatine (0.01mg/kg) was coadministered with subeffective dose of lithium (3mg/kg), it potentiated the antidepressant-like effect of subeffective dose of lithium. For the involvement of NMDA receptor in such effect, we administered NMDA receptor antagonist MK-801 (0.05mg/kg) with a combination of subeffective dose of lithium (3mg/kg) and agmatine (0.001mg/kg). A significant antidepressant-like effect was observed. Furthermore, when subeffective dose (50 and 75mg/kg) of NMDA was given it inhibited the synergistic effect of agmatine (0.01mg/kg) with lithium (3mg/kg). Hence, our finding demonstrate that agmatine have synergistic effect with lithium which is mediated by NMDA receptor pathway. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  15. Enzymes of agmatine degradation and the control of their synthesis in Streptococcus faecalis.

    OpenAIRE

    Simon, J P; Stalon, V

    1982-01-01

    Streptococcus faecalis ATCC 11700 uses agmatine as its sole energy source for growth. Agmatine deiminase and putrescine carbamoyltransferase are coinduced by growth on agmatine. Glucose and arginine were found to exert catabolite repression on the agmatine deiminase pathway. Four mutants unable to utilize agmatine as an energy source, isolated from the wild-type strain, exhibited three distinct phenotypes. Two of these strains showed essentially no agmatine deiminase, one mutant showed neglig...

  16. Pre-Treatment with Amifostine Protects against Cyclophosphamide-Induced Disruption of Taste in Mice

    Science.gov (United States)

    Mukherjee, Nabanita; Carroll, Brittany L.; Spees, Jeffrey L.; Delay, Eugene R.

    2013-01-01

    Cyclophosphamide (CYP), a commonly prescribed chemotherapy drug, has multiple adverse side effects including alteration of taste. The effects on taste are a cause of concern for patients as changes in taste are often associated with loss of appetite, malnutrition, poor recovery and reduced quality of life. Amifostine is a cytoprotective agent that was previously shown to be effective in preventing chemotherapy-induced mucositis and nephrotoxicity. Here we determined its ability to protect against chemotherapy-induced damage to taste buds using a mouse model of CYP injury. We conducted detection threshold tests to measure changes in sucrose taste sensitivity and found that administration of amifostine 30 mins prior to CYP injection protected against CYP-induced loss in taste sensitivity. Morphological studies showed that pre-treatment with amifostine prevented CYP-induced reduction in the number of fungiform taste papillae and increased the number of taste buds. Immunohistochemical assays for markers of the cell cycle showed that amifostine administration prevented CYP-induced inhibition of cell proliferation and also protected against loss of mature taste cells after CYP exposure. Our results indicate that treatment of cancer patients with amifostine prior to chemotherapy may improve their sensitivity for taste stimuli and protect the taste system from the detrimental effects of chemotherapy. PMID:23626702

  17. Pre-treatment with amifostine protects against cyclophosphamide-induced disruption of taste in mice.

    Directory of Open Access Journals (Sweden)

    Nabanita Mukherjee

    Full Text Available Cyclophosphamide (CYP, a commonly prescribed chemotherapy drug, has multiple adverse side effects including alteration of taste. The effects on taste are a cause of concern for patients as changes in taste are often associated with loss of appetite, malnutrition, poor recovery and reduced quality of life. Amifostine is a cytoprotective agent that was previously shown to be effective in preventing chemotherapy-induced mucositis and nephrotoxicity. Here we determined its ability to protect against chemotherapy-induced damage to taste buds using a mouse model of CYP injury. We conducted detection threshold tests to measure changes in sucrose taste sensitivity and found that administration of amifostine 30 mins prior to CYP injection protected against CYP-induced loss in taste sensitivity. Morphological studies showed that pre-treatment with amifostine prevented CYP-induced reduction in the number of fungiform taste papillae and increased the number of taste buds. Immunohistochemical assays for markers of the cell cycle showed that amifostine administration prevented CYP-induced inhibition of cell proliferation and also protected against loss of mature taste cells after CYP exposure. Our results indicate that treatment of cancer patients with amifostine prior to chemotherapy may improve their sensitivity for taste stimuli and protect the taste system from the detrimental effects of chemotherapy.

  18. Pretreatment with apoaequorin protects hippocampal CA1 neurons from oxygen-glucose deprivation.

    Science.gov (United States)

    Detert, Julia A; Adams, Erin L; Lescher, Jacob D; Lyons, Jeri-Anne; Moyer, James R

    2013-01-01

    Ischemic stroke affects ∼795,000 people each year in the U.S., which results in an estimated annual cost of $73.7 billion. Calcium is pivotal in a variety of neuronal signaling cascades, however, during ischemia, excess calcium influx can trigger excitotoxic cell death. Calcium binding proteins help neurons regulate/buffer intracellular calcium levels during ischemia. Aequorin is a calcium binding protein isolated from the jellyfish Aequorea victoria, and has been used for years as a calcium indicator, but little is known about its neuroprotective properties. The present study used an in vitro rat brain slice preparation to test the hypothesis that an intra-hippocampal infusion of apoaequorin (the calcium binding component of aequorin) protects neurons from ischemic cell death. Bilaterally cannulated rats received an apoaequorin infusion in one hemisphere and vehicle control in the other. Hippocampal slices were then prepared and subjected to 5 minutes of oxygen-glucose deprivation (OGD), and cell death was assayed by trypan blue exclusion. Apoaequorin dose-dependently protected neurons from OGD--doses of 1% and 4% (but not 0.4%) significantly decreased the number of trypan blue-labeled neurons. This effect was also time dependent, lasting up to 48 hours. This time dependent effect was paralleled by changes in cytokine and chemokine expression, indicating that apoaequorin may protect neurons via a neuroimmunomodulatory mechanism. These data support the hypothesis that pretreatment with apoaequorin protects neurons against ischemic cell death, and may be an effective neurotherapeutic.

  19. A ketogenic diet modifies glutamate, gamma-aminobutyric acid and agmatine levels in the hippocampus of rats: A microdialysis study.

    Science.gov (United States)

    Calderón, Naima; Betancourt, Luis; Hernández, Luis; Rada, Pedro

    2017-03-06

    The ketogenic diet (KD) is acknowledged as an unconventional option in the treatment of epilepsy. Several lines of investigation point to a possible role of glutamate and gamma-aminobutyric acid (GABA) as main contributors in this protective effect. Other biomolecules could also be involved in the beneficial consequence of the KD, for example, the diamine agmatine has been suggested to block imidazole and glutamate NMDA receptor and serves as an endogenous anticonvulsant in different animal models of epilepsy. In the present report, we have used microdialysis coupled to capillary electrophoresis to monitor microdialysate levels of GABA, glutamate and agmatine in the hippocampus of rats submitted to a KD for 15days compared to rats on a normal rat chow diet. A significant increase in GABA and agmatine levels while no change in glutamate levels was observed. These results support the notion that the KD modifies different transmitters favoring inhibitory over excitatory neurotransmitters. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Increased plasma agmatine levels in patients with schizophrenia.

    Science.gov (United States)

    Uzbay, Tayfun; Goktalay, Gokhan; Kayir, Hakan; Eker, Salih S; Sarandol, Asli; Oral, Sema; Buyukuysal, Levent; Ulusoy, Gokhan; Kirli, Selcuk

    2013-08-01

    Agmatine is an endogenous substance, synthesized from l-arginine, and it is proposed to be a new neurotransmitter. Preclinical studies indicated that agmatine may have an important role in the pathophysiology of schizophrenia. This study was organized to investigate plasma agmatine in patients with schizophrenia and in healthy controls. Eighteen patients with schizophrenia and 19 healthy individuals constituted the subjects. Agmatine levels in the plasma were measured using the HPLC method. The S100B protein level, which is a peripheral biomarker for brain damage, was also measured using the ELISA method. While plasma levels of agmatine in patients with schizophrenia were significantly increased (p agmatine levels as a clinical diagnostic test would significantly differentiate between patients with schizophrenia and those in the control group (predictive value: 0.969; p  0.05). A multiple regression analysis revealed that the age of the patient and the severity of the illness, as indicated by the PANSS score, significantly contributed the plasma agmatine levels in patients with schizophrenia. These results support the hypothesis that an excess agmatine release is important in the development of schizophrenia. The findings also imply that the plasma agmatine level may be a potential biomarker of schizophrenia. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. Gemfibrozil pretreatment proved protection against acute restraint stress-induced changes in the male rats' hippocampus.

    Science.gov (United States)

    Khalaj, Leila; Nejad, Sara Chavoshi; Mohammadi, Marzieh; Zadeh, Sadaf Sarraf; Pour, Marieh Hossein; Ahmadiani, Abolhassan; Khodagholi, Fariba; Ashabi, Ghorbangol; Alamdary, Shabnam Zeighamy; Samami, Elham

    2013-08-21

    Stress predisposes the brain to various neuropathological disorders. Fibrates like gemfibrozil, commonly used for hyperlipidemia, have not yet been examined for their protective/deteriorative potential against restraint stress-induced disturbances. Pretreatment of rats with a range of gemfibrozil concentrations showed significant protection against stress consequences at 90 mg/kg of gemfibrozil, as it resulted in the highest level of antioxidant defense system potentiation among other doses. It also reduced plasma corticosterone compared with the stressed animals. Administration of gemfibrozil (90 mg/kg) before stress induction was able to significantly induce the protein levels of some protective factors including hemeoxygenase-1 (HO-1) and NAD(P)H dehydrogenase quinone-1 (NQO-1) in the antioxidant nuclear factor erythroid-derived 2-like 2 (Nrf-2) pathway, as well as mitochondrial pro-survival proteins, including peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) and nuclear respiratory factor 1 (NRF-1). In parallel, the level of cleaved caspase-3 and apoptosis-inducing factor (AIF), two proteins involved in apoptotic cell death, and the number of damaged neurons detected in hematoxylin-eosin (H&E) stained hippocampus sections were suppressed in the presence of gemfibrozil. Herein, although gemfibrozil demonstrated protection against the restraint stress, considering its dose and context-dependent effects reported in the previous studies, as well as its common application in clinic, further investigations are essential to unravel its exact beneficial/deleterious effects in various neuronal contexts. Copyright © 2013 Elsevier B.V. All rights reserved.

  2. Agmatine attenuates reserpine-induced oral dyskinesia in mice: Role of oxidative stress, nitric oxide and glutamate NMDA receptors.

    Science.gov (United States)

    Cunha, Andréia S; Matheus, Filipe C; Moretti, Morgana; Sampaio, Tuane B; Poli, Anicleto; Santos, Danúbia B; Colle, Dirleise; Cunha, Mauricio P; Blum-Silva, Carlos H; Sandjo, Louis P; Reginatto, Flávio H; Rodrigues, Ana Lúcia S; Farina, Marcelo; Prediger, Rui D

    2016-10-01

    Dyskinesia consists in a series of trunk, limbs and orofacial involuntary movements that can be observed following long-term pharmacological treatment in some psychotic and neurological disorders such as schizophrenia and Parkinson's disease, respectively. Agmatine is an endogenous arginine metabolite that emerges as neuromodulator and a promising agent to manage diverse central nervous system disorders by modulating nitric oxide (NO) pathway, glutamate NMDA receptors and oxidative stress. Herein, we investigated the effects of a single intraperitoneal (i.p.) administration of different agmatine doses (10, 30 or 100mg/kg) against the orofacial dyskinesia induced by reserpine (1mg/kg,s.c.) in mice by measuring the vacuous chewing movements and tongue protusion frequencies, and the duration of facial twitching. The results showed an orofacial antidyskinetic effect of agmatine (30mg/kg, i.p.) or the combined administration of sub-effective doses of agmatine (10mg/kg, i.p.) with the NMDA receptor antagonists amantadine (1mg/kg, i.p.) and MK801 (0.01mg/kg, i.p.) or the neuronal nitric oxide synthase (NOS) inhibitor 7-nitroindazole (7-NI; 0.1mg/kg, i.p.). Reserpine-treated mice displayed locomotor activity deficits in the open field and agmatine had no effect on this response. Reserpine increased nitrite and nitrate levels in cerebral cortex, but agmatine did not reverse it. Remarkably, agmatine reversed the decrease of dopamine and non-protein thiols (NPSH) levels caused by reserpine in the striatum. However, no changes were observed in striatal immunocontent of proteins related to the dopaminergic system including tyrosine hydroxylase, dopamine transporter, vesicular monoamine transporter type 2, pDARPP-32[Thr75], dopamine D1 and D2 receptors. These results indicate that the blockade of NO pathway, NMDAR and oxidative stress are possible mechanisms associated with the protective effects of agmatine against the orofacial dyskinesia induced by reserpine in mice

  3. Effects of agmatine sulphate on facial nerve injuries.

    Science.gov (United States)

    Surmelioglu, O; Sencar, L; Ozdemir, S; Tarkan, O; Dagkiran, M; Surmelioglu, N; Tuncer, U; Polat, S

    2017-03-01

    To evaluate the effect of agmatine sulphate on facial nerve regeneration after facial nerve injury using electron and light microscopy. The study was performed on 30 male Wistar albino rats split into: a control group, a sham-treated group, a study control group, an anastomosis group, and an anastomosis plus agmatine sulphate treatment group. The mandibular branch of the facial nerve was dissected, and a piece was removed for histological and electron microscopic examination. Regeneration was better in the anastomosis group than in the study control group. However, the best regeneration findings were seen in the agmatine sulphate treatment group. There was a significant difference between the agmatine group and the others in terms of median axon numbers (p Agmatine sulphate treatment with anastomosis in traumatic facial paralysis may enhance nerve regeneration.

  4. L-carnitine pretreatment protects slow-twitch skeletal muscles in a rat model of ischemia-reperfusion injury.

    Science.gov (United States)

    Demirel, Mert; Kaya, Burak; Cerkez, Cem; Ertunc, Mert; Sara, Yildirim

    2013-10-01

    Ischemia-reperfusion (I/R) injury negatively affects the outcome of surgical interventions for amputated or severely traumatized extremities. This study aimed to evaluate the protective role of l-carnitine on the contractile properties of fast-twitch (extensor digitorum longus [EDL]) and slow-twitch (soleus [SOL]) skeletal muscles following I/R-induced injury in a rat model. Rats were divided into 4 groups (1) saline pretreatment, (2) l-carnitine pretreatment, (3) saline pretreatment and I/R, and (4) l-carnitine pretreatment and I/R. Twitch and tetanic contractions in the EDL and SOL muscles in each group were recorded. Additionally, a fatigue protocol was performed in these muscles. Twitch and tetanic contraction amplitudes were lower in the EDL and SOL muscles in which I/R was induced (P contraction amplitude in the SOL muscles following I/R (P muscles. l-Carnitine pretreatment did not alter the fatigue response in any of the muscles.

  5. Role of different types of potassium channels in the antidepressant-like effect of agmatine in the mouse forced swimming test.

    Science.gov (United States)

    Budni, Josiane; Gadotti, Vinícius M; Kaster, Manuella P; Santos, Adair R S; Rodrigues, Ana Lúcia S

    2007-12-01

    The administration of agmatine elicits an antidepressant-like effect in the mouse forced swimming test by a mechanism dependent on the inhibition of the NMDA receptors and the L-arginine-nitric oxide (NO) pathway. Since it has been reported that the NO can activate different types of potassium (K(+)) channels in several tissues, the present study investigates the possibility of synergistic interactions between different types of K(+) channel inhibitors and agmatine in the forced swimming test. Treatment of mice by i.c.v. route with subeffective doses of tetraethylammonium (a non specific inhibitor of K(+) channels, 25 pg/site), glibenclamide (an ATP-sensitive K(+) channels inhibitor, 0.5 pg/site), charybdotoxin (a large- and intermediate-conductance calcium-activated K(+) channel inhibitor, 25 pg/site) or apamin (a small-conductance calcium-activated K(+) channel inhibitor, 10 pg/site), augmented the effect of agmatine (0.001 mg/kg, i.p.) in the forced swimming test. Furthermore, the administration of agmatine and the K(+) channel inhibitors, alone or in combination, did not affect locomotion in the open-field test. Moreover, the reduction in the immobility time elicited by an active dose of agmatine (10 mg/kg, i.p.) in the forced swimming test was prevented by the pre-treatment of mice with the K(+) channel openers cromakalim (10 microg/site, i.c.v.) and minoxidil (10 microg/site, i.c.v.), without affecting locomotion. Together these data raise the possibility that the antidepressant-like effect of agmatine in the forced swimming test is related to its modulatory effects on neuronal excitability, via inhibition of K(+) channels.

  6. Protection of dichlorvos induced oxidative stress and nigrostriatal neuronal death by chronic Coenzyme Q10 pretreatment

    International Nuclear Information System (INIS)

    Binukumar, BK; Gupta, Nidhi; Bal, Amanjit; Gill, Kiran Dip

    2011-01-01

    Numerous epidemiological studies have shown an association between pesticide exposure and increased risk of developing Parkinson's diseases. Oxidative stress generated as a result of mitochondrial dysfunction has been implicated as an important factor in the etiology of Parkinson's disease. Previously, we reported that chronic dichlorvos exposure causes mitochondrial impairments and nigrostriatal neuronal death in rats. The present study was designed to test whether Coenzyme Q 10 (CoQ 10 ) administration has any neuroprotective effect against dichlorvos mediated nigrostriatal neuronal death, α-synuclein aggregation, and motor dysfunction. Male albino rats were administered dichlorvos by subcutaneous injection at a dose of 2.5 mg/kg body weight over a period of 12 weeks. Results obtained there after showed that dichlorvos exposure leads to enhanced mitochondrial ROS production, α-synuclein aggregation, decreased dopamine and its metabolite levels resulting in nigrostriatal neurodegeneration. Pretreatment by Coenzyme Q 10 (4.5 mg/kg ip for 12 weeks) to dichlorvos treated animals significantly attenuated the extent of nigrostriatal neuronal damage, in terms of decreased ROS production, increased dopamine and its metabolite levels, and restoration of motor dysfunction when compared to dichlorvos treated animals. Thus, the present study shows that Coenzyme Q 10 administration may attenuate dichlorvos induced nigrostriatal neurodegeneration, α-synuclein aggregation and motor dysfunction by virtue of its antioxidant action. - Highlights: → CoQ 10 administration attenuates dichlorvos induced nigrostriatal neurodegenaration. → CoQ 10 pre treatment leads to preservation of TH-IR neurons. → CoQ 10 may decrease oxidative damage and α-synuclin aggregation. → CoQ 10 treatment enhances motor function and protects rats from catalepsy.

  7. Antioxidative Peptides Derived from Enzyme Hydrolysis of Bone Collagen after Microwave Assisted Acid Pre-Treatment and Nitrogen Protection

    Directory of Open Access Journals (Sweden)

    Jin Sun

    2010-11-01

    Full Text Available This study focused on the preparation method of antioxidant peptides by enzymatic hydrolysis of bone collagen after microwave assisted acid pre-treatment and nitrogen protection. Phosphoric acid showed the highest ability of hydrolysis among the four other acids tested (hydrochloric acid, sulfuric acid and/or citric acid. The highest degree of hydrolysis (DH was 9.5% using 4 mol/L phosphoric acid with a ratio of 1:6 under a microwave intensity of 510 W for 240 s. Neutral proteinase gave higher DH among the four protease tested (Acid protease, neutral protease, Alcalase and papain, with an optimum condition of: (1 ratio of enzyme and substrate, 4760 U/g; (2 concentration of substrate, 4%; (3 reaction temperature, 55 °C and (4 pH 7.0. At 4 h, DH increased significantly (P < 0.01 under nitrogen protection compared with normal microwave assisted acid pre-treatment hydrolysis conditions. The antioxidant ability of the hydrolysate increased and reached its maximum value at 3 h; however DH decreased dramatically after 3 h. Microwave assisted acid pre-treatment and nitrogen protection could be a quick preparatory method for hydrolyzing bone collagen.

  8. Agmatine attenuates stress- and lipopolysaccharide-induced fever in rats

    Science.gov (United States)

    Aricioglu, Feyza; Regunathan, Soundar

    2010-01-01

    Physiological stress evokes a number of responses, including a rise in body temperature, which has been suggested to be the result of an elevation in the thermoregulatory set point. This response seems to share similar mechanisms with infectious fever. The aim of the present study was to investigate the effect of agmatine on different models of stressors [(restraint and lipopolysaccaride (LPS)] on body temperature. Rats were either restrained for 4 h or injected with LPS, both of these stressors caused an increase in body temperature. While agmatine itself had no effect on body temperature, treatment with agmatine (20, 40, 80 mg/kg intraperitoneally) dose dependently inhibited stress- and LPS-induced hyperthermia. When agmatine (80 mg/kg) was administered 30 min later than LPS (500 μg/kg) it also inhibited LPS-induced hyperthermia although the effect became significant only at later time points and lower maximal response compared to simultaneous administration. To determine if the decrease in body temperature is associated with an anti-inflammatory effect of agmatine, the nitrite/nitrate levels in plasma was measured. Agmatine treatment inhibited LPS-induced production of nitrates dose dependently. As an endogenous molecule, agmatine has the capacity to inhibit stress- and LPS-induced increases in body temperature. PMID:15936786

  9. Characterization and inactivation of an agmatine deiminase from Helicobacter pylori

    Energy Technology Data Exchange (ETDEWEB)

    Jones, Justin E.; Causey, Corey P.; Lovelace, Leslie; Knuckley, Bryan; Flick, Heather; Lebioda, Lukasz; Thompson, Paul R. (SC)

    2010-11-12

    Helicobacter pylori encodes a potential virulence factor, agmatine deiminase (HpAgD), which catalyzes the conversion of agmatine to N-carbamoyl putrescine (NCP) and ammonia - agmatine is decarboxylated arginine. Agmatine is an endogenous human cell signaling molecule that triggers the innate immune response in humans. Unlike H. pylori, humans do not encode an AgD; it is hypothesized that inhibition of this enzyme would increase the levels of agmatine, and thereby enhance the innate immune response. Taken together, these facts suggest that HpAgD is a potential drug target. Herein we describe the optimized expression, isolation, and purification of HpAgD (10-30 mg/L media). The initial kinetic characterization of this enzyme has also been performed. Additionally, the crystal structure of wild-type HpAgD has been determined at 2.1 {angstrom} resolution. This structure provides a molecular basis for the preferential deimination of agmatine, and identifies Asp198 as a key residue responsible for agmatine recognition, which has been confirmed experimentally. Information gathered from these studies led to the development and characterization of a novel class of haloacetamidine-based HpAgD inactivators. These compounds are the most potent AgD inhibitors ever described.

  10. Agmatine Modulation of Noradrenergic Neurotransmission in Isolated Rat Blood Vessels.

    Science.gov (United States)

    Török, Jozef; Zemančíková, Anna

    2016-06-30

    Agmatine, a vasoactive metabolite of L-arginine, is widely distributed in mammalian tissues including blood vessels. Agmatine binding to imidazoline and α₂-adrenoceptors induces a variety of physiological and pharmacological effects. We investigated the effect of agmatine on contractile responses of the rat pulmonary artery and portal vein induced by electrical stimulation of perivascular nerves and by exogenous adrenergic substances. Experiments were performed on isolated segments of rat main pulmonary artery and its extralobular branches, and portal vein suspended in organ bath containing modified Krebs bicarbonate solution and connected to a force-displacement transducer for isometric tension recording. Electrical field stimulation (EFS) produced tetrodotoxin-sensitive contractile responses of pulmonary artery and portal vein. Besides the well known vasorelaxant actions, we found that agmatine also produced a concentration-dependent inhibition of neurogenic contractions induced by EFS in pulmonary arteries; however, the agmatine treatment did not influence the responses to exogenous noradrenaline. The inhibitory effect on EFS-induced contractions was not abolished by the α₂-adrenoceptor antagonist rauwolscine. In portal vein, in contrast, agmatine increased spontaneous mechanical contractions and enhanced the contractions induced by EFS. The results suggest that agmatine can significantly influence vascular function of pulmonary arteries and portal veins by modulating sympathetically mediated vascular contractions by pre- and postsynaptic mechanisms.

  11. Role of agmatine in neurodegenerative diseases and epilepsy.

    Science.gov (United States)

    Moretti, Morgana; Matheus, Filipe C; de Oliveira, Paulo A; Neis, Vivian B; Ben, Juliana; Walz, Roger; Rodrigues, Ana Lucia S; Prediger, Rui Daniel

    2014-06-01

    Agmatine, a cationic polyamine synthesized after decarboxylation of L-arginine by the enzyme arginine decarboxylase, is an endogenous neuromodulator that emerges as a potential agent to manage diverse central nervous system (CNS) disorders. Consistent with its neuromodulatory and neuroprotective properties, there is increasing number of preclinical studies demonstrating the beneficial effects of exogenous agmatine administration on depression, anxiety, hypoxic ischemia, nociception, morphine tolerance, memory, Parkinson`s disease, Alzheimer`s disease, traumatic brain injury related alterations/disorders and epilepsy. The aim of this review is to summarize the knowledge about the effects of agmatine in CNS and point out its potential as new pharmacological treatment for diverse neurological and neurodegenerative diseases. Moreover, some molecular mechanisms underlying the neuroprotective effects of agmatine will be discussed.

  12. Agmatine ameliorates adjuvant induced arthritis and inflammatory cachexia in rats.

    Science.gov (United States)

    Taksande, Brijesh G; Gawande, Dinesh Y; Chopde, Chandrabhan T; Umekar, Milind J; Kotagale, Nandkishor R

    2017-02-01

    The present study investigated the pharmacological effect of agmatine in Complete Freud Adjuvant (CFA) induced arthritis and cachexia in rats. The rats were injected with CFA (0.1ml/rat) to induced symptoms of arthritis. Day 8 onwards of CFA administration, rats were injected daily with agmatine for next 7days, and arthritis score, body weights and food intake were monitored daily (g). Since cachexia is known to produce severe inflammation, malnutrition and inhibition of albumin gene expression, we have also monitored the total proteins, albumin, TNF-α and IL-6 levels in arthritic rats and its modulation by agmatine. In the present study, CFA treated rats showed a progressive reduction in both food intake and body weight. In addition analysis of blood serum of arthritis animals showed a significant reduction in proteins and albumin and significant elevation in tumor necrosis factor (TNF)-α and Interleukins (IL)-6. Chronic agmatine (20-40mg/kg, ip) treatment not only attenuated the signs of arthritis but also reverses anorexia and body weight loss in CFA treated rats. In addition, agmatine restored total protein and albumin and reduces TNF-α and IL-6 levels in arthritis rats. These results suggest that agmatine administration can prevent the body weights loss and symptoms of arthritis via inhibition of inflammatory cytokines. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  13. Agmatine Modulates the Phenotype of Macrophage Acute Phase after Spinal Cord Injury in Rats

    OpenAIRE

    Kim, Jae Hwan; Kim, Jae Young; Mun, Chin Hee; Suh, Minah; Lee, Jong Eun

    2017-01-01

    Agmatine is a decarboxylated arginine by arginine decarboxylase. Agmatine is known to be a neuroprotective agent. It has been reported that agmatine works as a NMDA receptor blocker or a competitive nitric oxide synthase inhibitor in CNS injuries. In spinal cord injury, agmatine showed reduction of neuropathic pain, improvement of locomotor function, and neuroprotection. Macrophage is a key cellular component in neuroinflammation, a major cause of impairment after spinal cord injury. Macropha...

  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. Antidepressant-like effect of agmatine is not mediated by serotonin

    DEFF Research Database (Denmark)

    Krass, Maarja; Wegener, Gregers; Vasar, Eero

    2008-01-01

    The aim of this study was to characterize the behavioral effects of systemically administered agmatine in animal models predictive of antidepressant- and anxiolytic-like activity and clarify whether the effects of agmatine depend on the intact serotonergic system. Only the highest dose of agmatin...

  16. Effects of agmatine on blood-brain barrier stabilization assessed by permeability MRI in a rat model of transient cerebral ischemia.

    Science.gov (United States)

    Ahn, S S; Kim, S H; Lee, J E; Ahn, K J; Kim, D J; Choi, H S; Kim, J; Shin, N-Y; Lee, S-K

    2015-02-01

    BBB disruption after acute ischemic stroke and subsequent permeability increase may be enhanced by reperfusion. Agmatine has been reported to attenuate BBB disruption. Our aim was to evaluate the effects of agmatine on BBB stabilization in a rat model of transient cerebral ischemia by using permeability dynamic contrast-enhanced MR imaging at early stages and subsequently to demonstrate the feasibility of dynamic contrast-enhanced MR imaging for the investigation of new therapies. Thirty-four male Sprague-Dawley rats were subjected to transient MCA occlusion for 90 minutes. Immediately after reperfusion, agmatine (100 mg/kg) or normal saline was injected intraperitoneally into the agmatine-treated group (n = 17) or the control group, respectively. MR imaging was performed after reperfusion. For quantitative analysis, regions of interest were defined within the infarct area, and values for volume transfer constant, rate transfer coefficient, volume fraction of extravascular extracellular space, and volume fraction of blood plasma were obtained. Infarct volume, infarct growth, quantitative imaging parameters, and numbers of factor VIII-positive cells after immunohistochemical staining were compared between control and agmatine-treated groups. Among the permeability parameters, volume transfer constant and volume fraction of extravascular extracellular space were significantly lower in the agmatine-treated group compared with the control group (0.05 ± 0.02 minutes(-1) versus 0.08 ± 0.03 minute(-1), P = .012, for volume transfer constant and 0.12 ± 0.06 versus 0.22 ± 0.15, P = .02 for volume fraction of extravascular extracellular space). Other permeability parameters were not significantly different between the groups. The number of factor VIII-positive cells was less in the agmatine-treated group than in the control group (3-fold versus 4-fold, P = .037). In ischemic stroke, agmatine protects the BBB, which can be monitored in vivo by quantification of

  17. Protective effect of preconditioning and adenosine pretreatment in experimental skeletal muscle reperfusion injury.

    Science.gov (United States)

    Papanastasiou, S; Estdale, S E; Homer-Vanniasinkam, S; Mathie, R T

    1999-07-01

    Prolonged ischaemia followed by reperfusion (I/R) of skeletal muscle results in significant tissue injury. Ischaemic preconditioning (IPC), achieved by repeated brief periods of I/R before prolonged ischaemia or adenosine pretreatment, can prevent I/R injury in cardiac muscle. The aim of this study was to ascertain in a rodent model if damage to skeletal muscle due to global hindlimb tourniquet-induced I/R could be similarly attenuated. Anaesthetized rats were randomized (n = 6-10 per group) to five groups: sham-operated controls; I/R (4 h of ischaemia, 2 h of reperfusion); IPC (three cycles of 10 min of ischaemia/10 min of reperfusion) alone; IPC immediately preceding I/R; or adenosine 1000 microg/kg immediately before I/R. At the end of reperfusion, biopsies were taken from the left gastrocnemius muscle for measurement of myeloperoxidase (MPO) and reduced glutathione (GSH). Before ischaemia and at the end of reperfusion, blood samples were taken for measurement of nitric oxide metabolites, tumour necrosis factor (TNF) alpha and macrophage inflammatory protein (MIP) 2. IPC before I/R resulted in lower levels of MPO (P < 0.001) and TNF-alpha (P = 0.004), and higher levels of GSH (P < 0.001) and nitric oxide metabolites (P = 0.002) than I/R alone. Adenosine had effects comparable to IPC pretreatment (P < 0.001 for MPO, P = 0.002 for GSH, P = 0.02 for nitric oxide metabolites and P = 0.001 for TNF-alpha). There was no difference in the blood pressure or the MIP-2 concentration among the groups. IPC or pretreatment with adenosine ameliorates the I/R injury of skeletal muscle.

  18. Pretreatment of Mice with Oligonucleotide prop5 Protects Them from Influenza Virus Infections

    Directory of Open Access Journals (Sweden)

    Kang Li

    2014-02-01

    Full Text Available Influenza A virus is a successful parasite and requires host factors to complete its life cycle. Prop5 is an antisense oligonucleotide, targeting programmed cell death protein 5 (PDCD5. In this study, we tested the antiviral activity of prop5 against mouse-adapted A/FM/1/47 strain of influenza A virus in a mouse model. Prop5 intranasally administered the mice at dosages of 10 and 20 mg/kg/d at 24 h and 30 min before infection, provided 80% and 100% survival rates and prolonged mean survival days in comparison with influenza virus-infected mice (both p < 0.01. Moreover, viral titres in mice pretreated with prop5, at dose of 10 and 20 mg/kg/d, had declined significantly on day two, four, and six post-infection compared with the yields in infected mice (p < 0.05 or p < 0.01; lung index in mice pretreated with prop5 (20 mg/kg/d had been inhibited on day six post-infection (p < 0.05. Western blotting and immunohistochemistry showed that prop5 could down-regulate the PDCD5 protein expression levels in lung tissues of infected mice. These data indicate that antisense oligonucleotide prop5 is a promising drug for prophylaxis and control influenza virus infections and provides an insight into the host-pathogen interaction.

  19. Pharmacological analysis of the inhibition produced by moxonidine and agmatine on the vasodepressor sensory CGRPergic outflow in pithed rats.

    Science.gov (United States)

    Rubio-Beltrán, Eloísa; Labastida-Ramírez, Alejandro; Hernández-Abreu, Oswaldo; MaassenVanDenBrink, Antoinette; Villalón, Carlos M

    2017-10-05

    Calcitonin gene-related peptide (CGRP) plays a role in several (patho)physiological functions, and modulation of its release is considered a therapeutic target. In this respect, electrical spinal (T 9 --T 12 ) stimulation of the perivascular sensory outflow in pithed rats produces vasodepressor responses mediated by CGRP release. This study investigated the role of imidazoline I 1 and I 2 receptors in the inhibition by moxonidine and agmatine of these vasodepressor responses. Male Wistar pithed rats (pretreated i.v. with 25mg/kg gallamine and 2mg/kg⋅min hexamethonium) received i.v. continuous infusions of methoxamine (20μg/kg⋅min) followed by physiological saline (0.02ml/min), moxonidine (1, 3, 10 or 30μg/kg⋅min) or agmatine (1000 or 3000μg/kg⋅min). Under these conditions, electrical stimulation (0.56-5.6Hz; 50V; 2ms) of the spinal cord (T 9 -T 12 ) produced frequency-dependent vasodepressor responses which were: (i) unchanged during saline infusion; and (ii) inhibited during the above infusions of moxonidine or agmatine. Moreover, using i.v. administrations, the inhibition by 3μg/kg⋅min moxonidine or 3000μg/kg⋅min agmatine (which failed to inhibit the vasodepressor responses by α-CGRP; 0.1-1µg/kg) was: (i) unaltered after saline (1ml/kg), rauwolscine (300μg/kg; α 2 -adrenoceptor antagonist) or BU224 (300μg/kg; imidazoline I 2 receptor antagonist); and (ii) reversed after AGN 192403 (3000μg/kg; imidazoline I 1 receptor antagonist). This reversion was relatively more pronounced after AGN 192403 plus rauwolscine. These blocking doses of antagonists lacked any effects on the electrically-induced vasodepressor responses. Therefore, the inhibition of the vasodepressor sensory CGRPergic outflow by moxonidine and agmatine is mainly mediated by prejunctional imidazoline I 1 receptors on perivascular sensory nerves. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Influence of ornithine decarboxylase antizymes and antizyme inhibitors on agmatine uptake by mammalian cells.

    Science.gov (United States)

    Ramos-Molina, Bruno; López-Contreras, Andrés J; Lambertos, Ana; Dardonville, Christophe; Cremades, Asunción; Peñafiel, Rafael

    2015-05-01

    Agmatine (4-aminobutylguanidine), a dicationic molecule at physiological pH, exerts relevant modulatory actions at many different molecular target sites in mammalian cells, having been suggested that the administration of this compound may have therapeutic interest. Several plasma membrane transporters have been implicated in agmatine uptake by mammalian cells. Here we report that in kidney-derived COS-7 cell line, at physiological agmatine levels, the general polyamine transporter participates in the plasma membrane translocation of agmatine, with an apparent Km of 44 ± 7 µM and Vmax of 17.3 ± 3.3 nmol h(-1) mg(-1) protein, but that at elevated concentrations, agmatine can be also taken up by other transport systems. In the first case, the physiological polyamines (putrescine, spermidine and spermine), several diguanidines and bis(2-aminoimidazolines) and the polyamine transport inhibitor AMXT-1501 markedly decreased agmatine uptake. In cells transfected with any of the three ornithine decarboxylase antizymes (AZ1, AZ2 and AZ3), agmatine uptake was dramatically reduced. On the contrary, transfection with antizyme inhibitors (AZIN1 and AZIN2) markedly increased the transport of agmatine. Furthermore, whereas putrescine uptake was significantly decreased in cells transfected with ornithine decarboxylase (ODC), the accumulation of agmatine was stimulated, suggesting a trans-activating effect of intracellular putrescine on agmatine uptake. All these results indicate that ODC and its regulatory proteins (antizymes and antizyme inhibitors) may influence agmatine homeostasis in mammalian tissues.

  1. Agmatine: clinical applications after 100 years in translation.

    Science.gov (United States)

    Piletz, John E; Aricioglu, Feyza; Cheng, Juei-Tang; Fairbanks, Carolyn A; Gilad, Varda H; Haenisch, Britta; Halaris, Angelos; Hong, Samin; Lee, Jong Eun; Li, Jin; Liu, Ping; Molderings, Gerhard J; Rodrigues, Ana Lúcia S; Satriano, Joseph; Seong, Gong Je; Wilcox, George; Wu, Ning; Gilad, Gad M

    2013-09-01

    Agmatine (decarboxylated arginine) has been known as a natural product for over 100 years, but its biosynthesis in humans was left unexplored owing to long-standing controversy. Only recently has the demonstration of agmatine biosynthesis in mammals revived research, indicating its exceptional modulatory action at multiple molecular targets, including neurotransmitter systems, nitric oxide (NO) synthesis and polyamine metabolism, thus providing bases for broad therapeutic applications. This timely review, a concerted effort by 16 independent research groups, draws attention to the substantial preclinical and initial clinical evidence, and highlights challenges and opportunities, for the use of agmatine in treating a spectrum of complex diseases with unmet therapeutic needs, including diabetes mellitus, neurotrauma and neurodegenerative diseases, opioid addiction, mood disorders, cognitive disorders and cancer. Copyright © 2013 Elsevier Ltd. All rights reserved.

  2. Mucuna pruriens Linn. seed extract pretreatment protects against cardiorespiratory and neuromuscular depressant effects of Naja sputatrix (Javan spitting cobra) venom in rats.

    Science.gov (United States)

    Fung, Shin Yee; Tan, Nget Hong; Sim, Si Mui; Marinello, Enrico; Guerranti, Roberto; Aguiyi, John Chinyere

    2011-04-01

    Mucuna pruriens has been used by native Nigerians as a prophylactic for snakebite. The protective effects of M. pruriens seed extract (MPE) were investigated against the pharmacological actions of N. sputatrix (Javan spitting cobra) venom in rats. The results showed that MPE-pretreatment protected against cardiorespiratory and, to a lesser extent, neuromuscular depressant effects of N. sputatrix venom. These may be explained at least in part by the neutralisation of the cobra venom toxins by anti-MPE antibodies elicited by the MPE pretreatment.

  3. No Protection against DSS-induced Colitis by Short-term Pretreatment with Seal or Fish Oils in Rats

    Directory of Open Access Journals (Sweden)

    Gülen Arslan

    2007-01-01

    Full Text Available Background: Omega-3 (n-3 polyunsaturated fatty acids (PUFAs have modulating effects in several chronic inflammatory conditions. The aim of the present study was to test whether prior short-term dietary supplementation with n-3 (fish or seal oil or n-6 (soy oil PUFA rich oils would protect the development of dextran sulfate sodium (DSS-induced colitis in rats.Methods: Forty-eight male Wistar rats were divided into 6 groups: no intervention, sham, DSS, seal oil + DSS, fi sh oil +DSS and soy oil + DSS. Following 7 days of acclimatisation, 1 mL oil (seal, fish or soy or distilled water (sham was administered by gavage day 8 to 14. Colitis was induced by 5% DSS in drinking water from day 15 to 21. Rats were sacrificed on day 23. Histological colitis (crypt and inflammation scores, faecal granulocyte marker protein (GMP and quantitative fatty acid composition in red blood cells were measured.Results: Pretreatment with fish or seal oils did not significantly influence DSS induced inflammation. In fact, all the oils tended to exacerbate the inflammation. Soy oil increased the mean crypt score (P < 0.04, but not the inflammation score or GMP. The ratio of n-6 to n-3 fatty acids (FAs was 11 to 1 and 10 to 1 in standard diet and in red blood cells of control rats, respectively. Following administration of DSS, the ratio fell in all treatment groups (P < 0.001. The lowest ratios were seen in the groups receiving DSS + fi sh or seal oils (around 6 to 1.Conclusion: Short-term pretreatment with fish or seal oils did not protect against subsequent induction of colitis by DSS in this rat model. Whether the high ratio of n-6 to n-3 FAs in the standard diet concealed effects of n-3 FA supplementation should be further investigated.

  4. Agmatine, a potential novel therapeutic strategy for depression.

    Science.gov (United States)

    Freitas, Andiara E; Neis, Vivian B; Rodrigues, Ana Lúcia S

    2016-12-01

    Major depressive disorder is the most common psychiatric disorder with lifetime prevalence of up to 20% worldwide. It is responsible for more years lost to disability than any other disorder. Despite the fact that current available antidepressant drugs are safe and effective, they are far from ideal. In addition to the need to administer the drugs for weeks or months to obtain clinical benefit, side effects are still a serious problem. Agmatine is an endogenous polyamine synthesized by the enzyme arginine decarboxylase. It modulates several receptors and is considered as a neuromodulator in the brain. In this review, studies demonstrating the antidepressant effects of agmatine are presented and discussed, as well as, the mechanisms of action related to these effects. Also, the potential beneficial effects of agmatine for the treatment of other neurological disorders are presented. In particular, we provide evidence to encourage future clinical studies investigating agmatine as a novel antidepressant drug. Copyright © 2016 Elsevier B.V. and ECNP. All rights reserved.

  5. 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.

  6. Regulation of metabolic products and gene expression in Fusarium asiaticum by agmatine addition.

    Science.gov (United States)

    Suzuki, Tadahiro; Kim, Young-Kyung; Yoshioka, Hifumi; Iwahashi, Yumiko

    2013-05-01

    The metabolic products resulting from the cultivation of F. asiaticum in agmatine were identified using capillary electrophoresis-time of flight mass spectrometry. Glyoxylic acid was detected from fungal cultures grown in agmatine, while it was absent in control cells. The abundance of other metabolic products of the glycolytic pathway also increased because of agmatine; however, there was no increase in the amounts of pyruvic acid or metabolites from the tricarboxylic acid cycle. Moreover, gene expression levels within Fusarium asiaticum exposed to agmatine were analyzed by DNA microarray. Changes in gene expression levels directed the changes in metabolic products. Our results suggest that acetyl coenzyme A, which is a starting substrate for the biosynthesis of deoxynivalenol (DON), was simultaneously produced by activated β-oxidation. Furthermore, the content of 4-aminobutyrate (GABA) was increased in the agmatine addition culture medium. GABA can be synthesized from agmatine through putrescine and might influence the regulation of DON-related genes.

  7. Focused Review: Agmatine in fermented foods

    Directory of Open Access Journals (Sweden)

    Fernanda eGalgano

    2012-06-01

    Full Text Available Polyamines (PAs are ubiquitous substances considered as bioregulators of numerous cell functions, being involved in cell growth, division and differentiation. These biogenic amines are also involved in tissue repairing and in intracellular signaling; in fact, because of their polycationic character, they interact strongly with membrane phospholipids and may play an important role in the regulation of membrane-linked enzymes. The intracellular polyamines content derives from the simultaneous regulation of their synthesis, catabolism, uptake and elimination; furthermore, PAs are present in all cell types at variable concentrations, but the highest levels are found in rapid-turnover tissues. In addition to spermidine, spermine and putrescine, also agmatine (AGM, deriving from arginine and identified in mammals in the 1990s, belongs to PAs and several studies have reported its possible positive role in secretagogues, neuronal, vascular, metabolic and therapeutic functions. Because of the low arginine decarboxylase activity (ADC in mammalians, the amounts of AGM found in their tissues can be only minimally ascribed to an endogenous de novo synthesis by the ADC, while a substantial AGM portion can be of dietary origin. Several food products contain only small amounts of polyamines, while higher concentrations can be found in fermented foods. PAs could also be considered as indicators of freshness in fish and meat products, being these moieties produced during food storage, thus confirming the main role of microorganisms in their synthesis. Although many biological functions have been attributed to polyamines, high levels of these compounds in foodstuffs can have toxicological effects; however, the safe level of dietary polyamines intake has not yet been established. In this paper the presence of AGM in different foodstuffs is discussed, taking also into account the various factors affecting its presence and concentration.

  8. Transport of diamines by Enterococcus faecalis is mediated by an agmatine-putrescine antiporter.

    OpenAIRE

    Driessen, A J; Smid, E J; Konings, W N

    1988-01-01

    Enterococcus faecalis ATCC 11700 is able to use arginine and the diamine agmatine as a sole energy source. Via the highly homologous deiminase pathways, arginine and agmatine are converted into CO2, NH3, and the end products ornithine and putrescine, respectively. In the arginine deiminase pathway, uptake of arginine and excretion of ornithine are mediated by an arginine-ornithine antiport system. The translocation of agmatine was studied in whole cells grown in the presence of arginine, agma...

  9. Protective effects of Mucuna pruriens seed extract pretreatment against cardiovascular and respiratory depressant effects of Calloselasma rhodostoma (Malayan pit viper) venom in rats.

    Science.gov (United States)

    Fung, S Y; Tan, N H; Sim, S M

    2010-12-01

    The protective effects of Mucuna pruriens seed extract (MPE) against the cardio-respiratory depressant and neuromuscular paralytic effects induced by injection of Calloselasma rhodostoma (Malayan pit viper) venom in anaesthetized rats were investigated. While MPE pretreatment did not reverse the inhibitory effect of the venom on the gastrocnemius muscle excitability, it significantly attenuated the venom-induced cardio-respiratory depressant effects (p < 0.05). The protection effects may have an immunological mechanism, as indicated by the presence of several proteins in the venom that are immunoreactive against anti-MPE. However, we cannot rule out the possibility that the pretreatment may exert a direct, non-immunological protective action against the venom.

  10. [Determination of endogenous agmatine in rat plasma by isotope dilution-gas chromatography-mass spectrometry].

    Science.gov (United States)

    Qiu, Zhongli; Lin, Ying; Xiong, Zhili; Xie, Jianwei

    2014-07-01

    A method for the determination of endogenous agmatine in rat plasma was developed by isotope dilution-gas chromatography-negative chemical ionization mass spectrometry (GC-NCI/MS). The plasma samples were analyzed after protein precipitation, evaporation, derivatization by hexafluoroacetone (HFAA), and clean-up on a Florisil SPE column. The GC-MS analysis utilized stable isotope d8-agmatine as internal standard. The samples after treatme were tested by negative chemical ionization with selected ion monitoring (SIM) which was set at m/z 492 (molecular ion of agmatine) and m/z 500 (molecular ion of internal standard). The limit of detection (LOD) of agmatine standard solution was 0.005 7 ng/mL. The calibration curve of the agmatine spiked in rat plasma showed a good linear relationship at the range of 1.14-57.0 ng/mL (r = 0.997). The recoveries of agmatine spiked in rat plasma ranged from 92.3% to 109.8%. Inter-day and intra-day precisions were less than 15%. The average concentration level of agmatine in rat plasma was (22 +/- 9) ng/mL, and there was no significant difference between male and female SD rats (p > 0.05). The method is high sensitive and specific, and can be used for the determination of endogenous agmatine in plasma. It provides a strong support for the subsequent research of agmatine.

  11. Exogenous agmatine has neuroprotective effects against restraint-induced structural changes in the rat brain

    Science.gov (United States)

    Zhu, Meng-Yang; Wang, Wei-Ping; Cai, Zheng-Wei; Regunathan, Soundar; Ordway, Gregory

    2009-01-01

    Agmatine is an endogenous amine derived from decarboxylation of arginine catalysed by arginine decarboxylase. Agmatine is considered a novel neuromodulator and possesses neuroprotective properties in the central nervous system. The present study examined whether agmatine has neuroprotective effects against repeated restraint stress-induced morphological changes in rat medial prefrontal cortex and hippocampus. Sprague-Dawley rats were subjected to 6 h of restraint stress daily for 21 days. Immunohistochemical staining with β-tubulin III showed that repeated restraint stress caused marked morphological alterations in the medial prefrontal cortex and hippocampus. Stress-induced alterations were prevented by simultaneous treatment with agmatine (50 mg/kg/day, i.p.). Interestingly, endogenous agmatine levels, as measured by high-performance liquid chromatography, in the prefrontal cortex and hippocampus as well as in the striatum and hypothalamus of repeated restraint rats were significantly reduced as compared with the controls. Reduced endogenous agmatine levels in repeated restraint animals were accompanied by a significant increase of arginine decarboxylase protein levels in the same regions. Moreover, administration of exogenous agmatine to restrained rats abolished increases of arginine decarboxylase protein levels. Taken together, these results demonstrate that exogenously administered agmatine has neuroprotective effects against repeated restraint-induced structural changes in the medial prefrontal cortex and hippocampus. These findings indicate that stress-induced reductions in endogenous agmatine levels in the rat brain may play a permissive role in neuronal pathology induced by repeated restraint stress. PMID:18364017

  12. Agmatine reduces extracellular glutamate during pentylenetetrazole-induced seizures in rat brain: A potential mechanism for the anticonvulsive effects

    OpenAIRE

    Feng, Yangzheng; LeBlanc, Michael H.; Regunathan, Soundar

    2005-01-01

    Glutamate has been implicated in the initiation and spread of seizure activity. Agmatine, an endogenous neuromodulator, is an antagonist of NMDA receptors and has anticonvulsive effects. Whether agmatine regulate glutamate release, as measured by in vivo microdialysis, is not known. In this study, we used pentylenetetrazole (PTZ)-induced seizure model to determine the effect of agmatine on extracellular glutamate in rat brain. We also determined the time course and the amount of agmatine that...

  13. Examination of Spray-Applied Oxsilan 9810/2 Steel Pretreatment on a Mine Resistant Ambush Protected (MRAP) Vehicle

    Science.gov (United States)

    2013-10-01

    Coating (CARC) system. The product demonstrated here is Oxsilan 9810/2, manufactured by Chemetall Inc., which satisfies the hexavalent chrome ...system. The product demonstrated here is Oxsilan 9810/2, manufactured by Chemetall Inc., and satisfies the hexavalent chrome prohibition while...2 Omitting this pretreatment/conversion coating step was justified because hexavalent chromium- based pretreatments, such as DOD-P-15328 (8

  14. Myocardial protection during elective coronary artery bypasses grafting by pretreatment with omega-3 polyunsaturated fatty acids

    Directory of Open Access Journals (Sweden)

    Veljović Milić

    2013-01-01

    PUFAs group was statistically significantly higher compared to the control group after 10, 20 and 30 min of reperfusion (35.5% vs 50.4%, p < 0.0004; 25.8 % vs 48.7%, p < 0.0001 and 25.8% vs 45.6%, p < 0.0002, respectively. The level of TnT, 4 and 24 h after CPB, was significantly higher in the control group compared to PUFAs group, with statistically significant differences (11.4 vs 6.6, p < 0.009 and 12.7 vs 5.9, p < 0.008, respectively. The level of CK-MB, 4 h after CPB, was significantly higher in the control group compared to PUFAs group (61.9 vs 37.7, p < 0.008, but its level, 24 h after CPB, was not statistically different between the two groups (58.9 vs 40.6, p < 0.051. Conclusion. Treatment with omega-3 PUFAs administered preoperatively promoted early metabolic recovery of the heart after elective CABG and improved myocardial protection. This study showed that omega-3 emulsion should not be considered only as a nutritional supplement but also as a clinically safe and potent cardioprotective adjunct during CPB.

  15. Transcriptome profiling of Lactococcus lactis subsp. cremoris CECT 8666 in response to agmatine

    Directory of Open Access Journals (Sweden)

    Beatriz del Rio

    2016-03-01

    Full Text Available The dairy strain Lactococcus lactis subsp. cremoris CECT 8666 (formerly GE2-14 synthesizes the biogenic amine putrescine from agmatine via the agmatine deiminase (AGDI pathway [1]. The AGDI cluster of L. lactis is composed by five genes aguR, aguB, aguD, aguA and aguC. The last four genes are co-transcribed as a single policistronic mRNA forming the catabolic operon aguBDAC, which encodes the proteins necessary for agmatine uptake and its conversion into putrescine [1,2]. The first gene of the cluster, aguR, encodes a transmembrane protein that functions as a one-component signal transduction system that senses the agmatine concentration of the medium and accordingly regulates the transcription of aguBDAC [2]. The catabolic operon aguBDAC is transcriptionally activated by agmatine [2] and transcriptionally regulated by carbon catabolite repression (CCR via glucose, but not by other sugars such as lactose or galactose [1,3]. On the contrary, the transcription of the aguR regulatory gene is not subject to CCR regulation [1,3] nor is regulated by agmatine [2]. In this study we report the transcriptional profiling of L. lactis subsp. cremoris CECT 8666 grown in M17 medium with galactose (GalM17 as carbon source and supplemented with agmatine, compared to that of the strain grown in the same culture medium without agmatine. The transcriptional profiling data of agmatine-regulated genes were deposited in the Gene Expression Omnibus (GEO database under Accession no. GSE74808. Keywords: Lactococcus lactis, Biogenic amines, Putrescine, Agmatine deiminase, Agmatine

  16. Agmatine Modulates the Phenotype of Macrophage Acute Phase after Spinal Cord Injury in Rats.

    Science.gov (United States)

    Kim, Jae Hwan; Kim, Jae Young; Mun, Chin Hee; Suh, Minah; Lee, Jong Eun

    2017-10-01

    Agmatine is a decarboxylated arginine by arginine decarboxylase. Agmatine is known to be a neuroprotective agent. It has been reported that agmatine works as a NMDA receptor blocker or a competitive nitric oxide synthase inhibitor in CNS injuries. In spinal cord injury, agmatine showed reduction of neuropathic pain, improvement of locomotor function, and neuroprotection. Macrophage is a key cellular component in neuroinflammation, a major cause of impairment after spinal cord injury. Macrophage has subtypes, M1 and M2 macrophages. M1 macrophage induces a pro-inflammatory response, but M2 inspires an anti-inflammatory response. In this study, it was clarified whether the neuroprotective effect of agmatine is related with the modulation of macrophage subdivision after spinal cord injury. Spinal cord injury was induced in rats with contusion using MASCIS. Animals received agmatine (100 mg/kg, IP) daily for 6 days beginning the day after spinal cord injury. The proportion of M1 and M2 macrophages are confirmed with immunohistochemistry and FACS. CD206 + & ED1 + cells were counted as M2 macrophages. The systemic treatment of agmatine increased M2 macrophages caudal side to epicenter 1 week after spinal cord injury in immunohistochemistry. M2 macrophage related markers, Arginase-1 and CD206 mRNA, were increased in the agmatine treatment group and M2 macrophage expressing and stimulated cytokine, IL-10 mRNA, also was significantly overexpressed by agmatine injection. Among BMPs, BMP2/4/7, agmatine significantly increased only the expression of BMP2 known to reduce M1 macrophage under inflammatory status. These results suggest that agmatine reduces impairment after spinal cord injury through modulating the macrophage phenotype.

  17. Pretreatment by low-dose fibrates protects against acute free fatty acid-induced renal tubule toxicity by counteracting PPARα deterioration

    International Nuclear Information System (INIS)

    Takahashi, Kyoko; Kamijo, Yuji; Hora, Kazuhiko; Hashimoto, Koji; Higuchi, Makoto; Nakajima, Takero; Ehara, Takashi; Shigematsu, Hidekazu; Gonzalez, Frank J.; Aoyama, Toshifumi

    2011-01-01

    Development of a preventive strategy against tubular damage associated with proteinuria is of great importance. Recently, free fatty acid (FFA) toxicities accompanying proteinuria were found to be a main cause of tubular damage, which was aggravated by insufficiency of peroxisome proliferator-activated receptor alpha (PPARα), suggesting the benefit of PPARα activation. However, an earlier study using a murine acute tubular injury model, FFA-overload nephropathy, demonstrated that high-dose treatment of PPARα agonist (0.5% clofibrate diet) aggravated the tubular damage as a consequence of excess serum accumulation of clofibrate metabolites due to decreased kidney elimination. To induce the renoprotective effects of PPARα agonists without drug accumulation, we tried a pretreatment study using low-dose clofibrate (0.1% clofibrate diet) using the same murine model. Low-dose clofibrate pretreatment prevented acute tubular injuries without accumulation of its metabolites. The tubular protective effects appeared to be associated with the counteraction of PPARα deterioration, resulting in the decrease of FFAs influx to the kidney, maintenance of fatty acid oxidation, diminution of intracellular accumulation of undigested FFAs, and attenuation of disease developmental factors including oxidative stress, apoptosis, and NFκB activation. These effects are common to other fibrates and dependent on PPARα function. Interestingly, however, clofibrate pretreatment also exerted PPARα-independent tubular toxicities in PPARα-null mice with FFA-overload nephropathy. The favorable properties of fibrates are evident when PPARα-dependent tubular protective effects outweigh their PPARα-independent tubular toxicities. This delicate balance seems to be easily affected by the drug dose. It will be important to establish the appropriate dosage of fibrates for treatment against kidney disease and to develop a novel PPARα activator that has a steady serum concentration regardless of

  18. Mechanistic studies of the agmatine deiminase from Listeria monocytogenes.

    Science.gov (United States)

    Soares, Charles A; Knuckley, Bryan

    2016-06-01

    Listeria monocytogenes is a Gram-positive food-borne pathogen that is capable of living within extreme environments (i.e. low temperatures and pH). This ability to survive in such conditions may arise, at least in part, from agmatine catabolism via the agmatine deiminase system (AgDS). This catabolic pathway utilizes an agmatine deiminase (AgD) to hydrolyse agmatine into N-carbamoylputrescine (NCP), with concomitant release of ammonia, which increases the pH, thus mitigating the ill effects of the acidic environment. Given the potential significance of this pathway for cell survival, we set out to study the catalytic mechanism of the AgD encoded by L. monocytogenes In the present paper, we describe the catalytic mechanism employed by this enzyme based on pH profiles, pKa measurements of the active site cysteine and solvent isotope effects (SIE). In addition, we report inhibition of this enzyme by two novel AgD inhibitors, i.e. N-(4-aminobutyl)-2-fluoro-ethanimidamide (ABFA) and N-(4-aminobutyl)-2-chloro-ethanimidamide (ABCA). In contrast with other orthologues, L. monocytogenes AgD does not use the reverse protonation or substrate-assisted mechanism, which requires an active site cysteine with a high pKa and has been commonly seen in other members of the guanidinium-modifying enzyme (GME) superfamily. Instead, the L. monocytogenes AgD has a low pKa cysteine in the active site leading to an alternative mechanism of catalysis. This is the first time that this mechanism has been observed in the GME superfamily and is significant because it explains why previously developed mechanism-based inactivators of AgDs are ineffective against this orthologue. © 2016 The Author(s). published by Portland Press Limited on behalf of the Biochemical Society.

  19. Supraspinally-administered agmatine attenuates the development of oral fentanyl self-administration

    Science.gov (United States)

    Wade, Carrie L.; Schuster, Daniel J.; Domingo, Kristine M.; Kitto, Kelley F.; Fairbanks, Carolyn A.

    2009-01-01

    The decarboxylation product of arginine, agmatine, has effectively reduced or prevented opioid-induced tolerance and dependence when given either systemically (intraperitoneally or subcutaneously) or centrally (intrathecally or intracerebroventricularly). Systemically administered agmatine also reduces the escalation phase of intravenous fentanyl self-administration in rats. The present study assessed whether centrally (intracerebroventricular, i.c.v.) delivered agmatine could prevent the development of fentanyl self-administration in mice. Mice were trained to respond under a fixed-ratio 1 (FR1) schedule for either fentanyl (0.7 μg/70 μl, p.o.) or food reinforcement. Agmatine (10 nmol/5 μl), injected i.c.v. 12-14h before the first session and every other evening (12-14h before session) for 2 weeks, completely attenuated oral fentanyl self-administration (but not food-maintained responding) compared to saline-injected controls. When agmatine was administered after fentanyl self-administration had been established (day 8) it had no attenuating effects on bar pressing. This dose of agmatine does not decrease locomotor activity as assessed by rotarod. The present findings significantly extend the previous observation that agmatine prevents opioid-maintained behavior to a chronic model of oral fentanyl self-administration as well as identifying a supraspinal site of action for agmatine inhibition of drug addiction. PMID:18495108

  20. Multiple Two-Component Systems of Streptococcus mutans Regulate Agmatine Deiminase Gene Expression and Stress Tolerance▿

    OpenAIRE

    Liu, Yaling; Burne, Robert A.

    2009-01-01

    Induction of the agmatine deiminase system (AgDS) of Streptococcus mutans requires agmatine and is optimal at low pH. We show here that the VicRK, ComDE, and CiaRH two-component systems influence AgDS gene expression in response to acidic and thermal stresses.

  1. Distribution, Regulation and Role of the Agmatine Deiminase System in Mutans Streptococci

    OpenAIRE

    Griswold, Ann R.; Nascimento, Marcelle M.; Burne, Robert A.

    2009-01-01

    The agmatine deiminase system was identified in seven strains of mutans streptococci. Genes encoding the AgDS of Streptococcus rattus FA-1 were sequenced and found to share homology with the agu genes of Streptococcus mutans UA159. Agmatine inhibited bacterial growth, suggesting that the AgDS degrades a deleterious substance into useful compounds.

  2. Agmatine enhances antidepressant potency of MK-801 and conventional antidepressants in mice.

    Science.gov (United States)

    Neis, Vivian Binder; Moretti, Morgana; Manosso, Luana Meller; Lopes, Mark W; Leal, Rodrigo Bainy; Rodrigues, Ana Lúcia S

    2015-03-01

    Agmatine, an endogenous guanidine amine, has been shown to produce antidepressant-like effects in animal studies. This study investigated the effects of the combined administration of agmatine with either conventional monoaminergic antidepressants or the N-methyl-D-aspartate (NMDA) receptor antagonist MK-801 in the tail suspension test (TST) in mice. The aim was to evaluate the extent of the antidepressant synergism by examining the ability of a fixed dose of agmatine to shift the antidepressant potency of fluoxetine, imipramine, bupropion and MK-801. A sub-effective dose of agmatine (0.0001 mg/kg, p.o.) significantly increased the potency by which fluoxetine, imipramine, bupropion and MK-801 decreased immobility time in the TST by 2-fold (fluoxetine), 10-fold (imipramine and bupropion) and 100-fold (MK-801). Combined with previous evidence indicating a role of monoaminergic systems in the effect of agmatine, the current data suggest that agmatine may modulate monoaminergic neurotransmission and augment the activity of conventional antidepressants. Moreover, this study found that agmatine substantially augmented the antidepressant-like effect of MK-801, reinforcing the notion that this compound modulates NMDA receptor activation. These preclinical data may stimulate future clinical studies testing the effects of augmentation therapy with agmatine for the management of depressive disorders. Copyright © 2014 Elsevier Inc. All rights reserved.

  3. Evidence for oral agmatine sulfate safety--a 95-day high dosage pilot study with rats.

    Science.gov (United States)

    Gilad, Gad M; Gilad, Varda H

    2013-12-01

    Agmatine, decarboxylated arginine, exerts beneficial effects in various experimental disease models. Clinical trials indicate the safety and effectiveness of short-term (up to 21 days) high dose regimens of oral agmatine sulfate, but longer term studies are lacking. This pilot study undertook to assess the safety of a longer term high dosage oral agmatine sulfate in laboratory rats. Adult Wistar rats consumed 5.3 g/l agmatine sulfate in their drinking water for 95 days, a regimen estimated to result in a daily dosage of absorbed agmatine of about 100mg/kg. Animals' body weight, water consumption and blood pressure were periodically measured, and general cage behavior, fur appearance, urination and feces appearance monitored. These parameters were also determined at 20 days after treatment cessation (day 115). On days 95 and 115, animals were euthanized for gross necropsy assessment. Agmatine-treated rats showed slight, but significant reductions in body weight and blood pressure, and reduced water consumption during treatment, which recovered completely within 20 days after treatment cessation. Otherwise, no abnormal behaviors or organ pathologies were observed. These findings are first to suggest apparent safety of sub-chronic high dosage dietary agmatine sulfate in laboratory rats, thus lending further support to the therapeutic applications of agmatine. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. Transcriptome profiling of Lactococcus lactis subsp. cremoris CECT 8666 in response to agmatine

    NARCIS (Netherlands)

    Del Rio, Beatriz; Redruello, Begoña; Martin, M Cruz; Fernandez, Maria; de Jong, Anne; Kuipers, Oscar P; Ladero, Victor; Alvarez, Miguel A

    2016-01-01

    The dairy strain Lactococcus lactis subsp. cremoris CECT 8666 (formerly GE2-14) synthesizes the biogenic amine putrescine from agmatine via the agmatine deiminase (AGDI) pathway [1]. The AGDI cluster of L. lactis is composed by five genes aguR, aguB, aguD, aguA and aguC. The last four genes are

  5. Transport of Diamines by Enterococcus faecalis Is Mediated by an Agmatine-Putrescine Antiporter

    NARCIS (Netherlands)

    Driessen, Arnold J.M.; Smid, Eddy J.; Konings, Wilhelmus

    1988-01-01

    Enterococcusfaecalis ATCC 11700 is able to use arginine and the diamine agmatine as a sole energy source. Via the highly homologous deiminase pathways, arginine and agmatine are converted into CO2, NH3, and the end products ornithine and putrescine, respectively. In the arginine deiminase pathway,

  6. Agmatine prevents acute chlorpromazine-induced neurotoxicity in rats

    Directory of Open Access Journals (Sweden)

    Dejanović Bratislav

    2015-01-01

    Full Text Available The present study was directed to potentially beneficial effects of agmatine (AGM on oxidative/nitrosative stress development in selective vulnerable brain regions during chlorpromazine (HPZ treatment in rats. All tested compounds were administered intraperitoneally (i.p. in one single dose. The animals were divided into control (K, 0.9 % saline solution, HPZ (HPZ, 38.7 mg/kg b.w., HPZ+AGM (AGM, 75 mg/kg b.w. immediately after HPZ, 38.7 mg/kg b.w. i.p. and AGM (AGM, 75 mg/kg b.w. groups. Rats were sacrificed by decapitation 24 hours after the treatment. Analysis of data showed that HPZ+AGM injection significantly decreased drug concentration compared with HPZ-animals (p<0.05. HPZ application increased lipid peroxidation (p<0.001 in cortex, striatum and hippocampus, nitrite and nitrate concentration (p<0.001 in all three brain regions and superoxide anion production (p<0.05 in all three brain structures, while completely damaged enzymatic antioxidative defense system (superoxide dismutase in both cortex and striatum p<0.05 and hippocampus p<0.001; glutathion reductase in both cortex and striatum p<0.001 and hippocampus p<0.05; catalase in cortex p<0.001 and both striatum and hippocampus p<0.05. However, treatment with AGM significantly attenuated the oxidative stress parameters compared to HPZ-group (lipid peroxidation in cortex p<0.001, striatum p<0.01 and hippocampus p<0.05; nitrite and nitrate concentration in all three brain structures p<0.001 and restores antioxidant capacity to control values in all examined brain structures. Immunohistochemical staining of GFAP molecules in rats showed an increase in the number of positive cells 24 h after acute HPZ-administration. All these results indicate that AGM may be effective in the protection of HPZ-induced brain injury in rats.

  7. Influence of ornithine decarboxylase antizymes and antizyme inhibitors on agmatine uptake by mammalian cells

    DEFF Research Database (Denmark)

    Ramos-Molina, Bruno; López-Contreras, Andrés J; Lambertos, Ana

    2015-01-01

    Agmatine (4-aminobutylguanidine), a dicationic molecule at physiological pH, exerts relevant modulatory actions at many different molecular target sites in mammalian cells, having been suggested that the administration of this compound may have therapeutic interest. Several plasma membrane...... transporters have been implicated in agmatine uptake by mammalian cells. Here we report that in kidney-derived COS-7cell line, at physiological agmatine levels, the general polyamine transporter participates in the plasma membrane translocation of agmatine, with an apparent Km of 44 ± 7 µM and V max of 17.......3 ± 3.3 nmol h(-1) mg(-1) protein, but that at elevated concentrations, agmatine can be also taken up by other transport systems. In the first case, the physiological polyamines (putrescine, spermidine and spermine), several diguanidines and bis(2-aminoimidazolines) and the polyamine transport inhibitor...

  8. OCT2 and MATE1 Provide Bi-directional Agmatine Transport

    Science.gov (United States)

    Winter, Tate N.; Elmquist, William F.; Fairbanks, Carolyn A.

    2015-01-01

    Agmatine is a biogenic amine (l-arginine metabolite) of potential relevance to several central nervous system (CNS) conditions. The identities of transporters underlying agmatine and polyamine disposition in mammalian systems are not well defined. The SLC-family organic cation transporters (OCT) OCT1 and OCT2 and multidrug and toxin extrusion transporter-1 (MATE1) are transport systems that may be of importance for the cellular disposition of agmatine and putrescine. We investigated the transport of [3H]-agmatine and [3H]-putrescine in human embryonic kidney (HEK293) cells stably-transfected with hOCT1-, hOCT2-, and hMATE1. Agmatine transport by hOCT1 and hOCT2 was concentration-dependent, whereas only hOCT2 demonstrated pH-dependent transport. hOCT2 exhibited a greater affinity for agmatine (Km = 1.84 ± 0.38 mM) than did hOCT1 (Km = 18.73 ± 4.86 mM). Putrescine accumulation was pH- and concentration-dependent in hOCT2-HEK cells (Km = 11.29 ± 4.26 mM) but not hOCT1-HEK cells. Agmatine accumulation, in contrast to putrescine, was significantly enhanced by hMATE1 over-expression, and was saturable (Km = 240 ± 31 μM; Vmax = 192 ± 10 pmol/min/mg protein). Intracellular agmatine was also trans-stimulated (effluxed) from hMATE1-HEK cells in the presence of an inward proton-gradient. The hMATE1-mediated transport of agmatine was inhibited by polyamines, the prototypical substrates MPP+ and paraquat, as well as guanidine and arcaine, but not l-arginine. These results suggest that agmatine disposition may be influenced by hOCT2 and hMATE1, two transporters critical in the renal elimination of xenobiotic compounds. PMID:21128598

  9. N-acetylcysteine-pretreated human embryonic mesenchymal stem cell administration protects against bleomycin-induced lung injury.

    Science.gov (United States)

    Wang, Qiao; Zhu, Hong; Zhou, Wu-Gang; Guo, Xiao-Can; Wu, Min-Juan; Xu, Zhen-Yu; Jiang, Jun-feng; Shen, Ce; Liu, Hou-Qi

    2013-08-01

    The transplantation of mesenchymal stem cells (MSCs) has been reported to be a promising approach in the treatment of acute lung injury. However, the poor efficacy of transplanted MSCs is one of the serious handicaps in the progress of MSC-based therapy. Therefore, the purpose of this study was to investigate whether the pretreatment of human embryonic MSCs (hMSCs) with an antioxidant, namely N-acetylcysteine (NAC), can improve the efficacy of hMSC transplantation in lung injury. In vitro, the antioxidant capacity of NAC-pretreated hMSCs was assessed using intracellular reactive oxygen species (ROS) and glutathione assays and cell adhesion and spreading assays. In vivo, the therapeutic potential of NAC-pretreated hMSCs was assessed in a bleomycin-induced model of lung injury in nude mice. The pretreatment of hMSCs with NAC improved antioxidant capacity to defend against redox imbalances through the elimination of cellular ROS, increasing cellular glutathione levels, and the enhancement of cell adhesion and spreading when exposed to oxidative stresses in vitro. In addition, the administration of NAC-pretreated hMSCs to nude mice with bleomycin-induced lung injury decreased the pathological grade of lung inflammation and fibrosis, hydroxyproline content and numbers of neutrophils and inflammatory cytokines in bronchoalveolar lavage fluid and apoptotic cells, while enhancing the retention and proliferation of hMSCs in injured lung tissue and improving the survival rate of mice compared with results from untreated hMSCs. The pretreatment of hMSCs with NAC could be a promising therapeutic approach to improving cell transplantation and, therefore, the treatment of lung injury.

  10. Agmatine attenuates brain edema through reducing the expression of aquaporin-1 after cerebral ischemia

    Science.gov (United States)

    Kim, Jae Hwan; Lee, Yong Woo; Park, Kyung Ah; Lee, Won Taek; Lee, Jong Eun

    2010-01-01

    Brain edema is frequently shown after cerebral ischemia. It is an expansion of brain volume because of increasing water content in brain. It causes to increase mortality after stroke. Agmatine, formed by the decarboxylation of -arginine by arginine decarboxylase, has been shown to be neuroprotective in trauma and ischemia models. The purpose of this study was to investigate the effect of agmatine for brain edema in ischemic brain damage and to evaluate the expression of aquaporins (AQPs). Results showed that agmatine significantly reduced brain swelling volume 22 h after 2 h middle cerebral artery occlusion in mice. Water content in brain tissue was clearly decreased 24 h after ischemic injury by agmatine treatment. Blood–brain barrier (BBB) disruption was diminished with agmatine than without. The expressions of AQPs-1 and -9 were well correlated with brain edema as water channels, were significantly decreased by agmatine treatment. It can thus be suggested that agmatine could attenuate brain edema by limitting BBB disruption and blocking the accumulation of brain water content through lessening the expression of AQP-1 after cerebral ischemia. PMID:20029450

  11. Participation of hippocampal agmatine in spatial learning: an in vivo microdialysis study.

    Science.gov (United States)

    Rushaidhi, Madihah; Jing, Yu; Zhang, Hu; Liu, Ping

    2013-02-01

    Agmatine, decarboxylated arginine, is widely distributed in mammalian brains and is considered as a novel putative neurotransmitter. Recent research demonstrates spatial learning-induced increases in agmatine in memory-related structures at the tissue and presynaptic terminal levels. By using the in vivo microdialysis technique coupled with highly sensitive liquid chromatography/mass spectrometry assay, we investigated dynamic changes of extracellular agmatine in the rat dorsal hippocampus before, during and after water maze training to find a fixed hidden platform on the first and forth day of testing. It was firstly noted that the basal level of extracellular agmatine was significantly elevated on day 4. While swimming per se had no effect, a rapid rise (2-6 folds) in extracellular agmatine was observed during water maze training regardless of testing day. Such learning-induced rise was found to successively lessen across the multiple blocks of training on day 1. However, this pattern was reversed on day 4 when the platform was removed during the final training trial. The present study, for the first time, demonstrates water maze training-induced increase of extracellular agmatine in the dorsal hippocampus. The results suggest a role of endogenous agmatine in the encoding and retrieval of spatial information. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. Biomass pretreatment

    Science.gov (United States)

    Hennessey, Susan Marie; Friend, Julie; Elander, Richard T; Tucker, III, Melvin P

    2013-05-21

    A method is provided for producing an improved pretreated biomass product for use in saccharification followed by fermentation to produce a target chemical that includes removal of saccharification and or fermentation inhibitors from the pretreated biomass product. Specifically, the pretreated biomass product derived from using the present method has fewer inhibitors of saccharification and/or fermentation without a loss in sugar content.

  13. Novel Route for Agmatine Catabolism in Aspergillus niger Involves 4-Guanidinobutyrase.

    Science.gov (United States)

    Kumar, Sunil; Saragadam, Tejaswani; Punekar, Narayan S

    2015-08-15

    Agmatine, a significant polyamine in bacteria and plants, mostly arises from the decarboxylation of arginine. The functional importance of agmatine in fungi is poorly understood. The metabolism of agmatine and related guanidinium group-containing compounds in Aspergillus niger was explored through growth, metabolite, and enzyme studies. The fungus was able to metabolize and grow on l-arginine, agmatine, or 4-guanidinobutyrate as the sole nitrogen source. Whereas arginase defined the only route for arginine catabolism, biochemical and bioinformatics approaches suggested the absence of arginine decarboxylase in A. niger. Efficient utilization by the parent strain and also by its arginase knockout implied an arginase-independent catabolic route for agmatine. Urea and 4-guanidinobutyrate were detected in the spent medium during growth on agmatine. The agmatine-grown A. niger mycelia contained significant levels of amine oxidase, 4-guanidinobutyraldehyde dehydrogenase, 4-guanidinobutyrase (GBase), and succinic semialdehyde dehydrogenase, but no agmatinase activity was detected. Taken together, the results support a novel route for agmatine utilization in A. niger. The catabolism of agmatine by way of 4-guanidinobutyrate to 4-aminobutyrate into the Krebs cycle is the first report of such a pathway in any organism. A. niger GBase peptide fragments were identified by tandem mass spectrometry analysis. The corresponding open reading frame from the A. niger NCIM 565 genome was located and cloned. Subsequent expression of GBase in both Escherichia coli and A. niger along with its disruption in A. niger functionally defined the GBase locus (gbu) in the A. niger genome. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  14. Structure and stability of complexes of agmatine with some functional receptor residues of proteins

    Science.gov (United States)

    Remko, Milan; Broer, Ria; Remková, Anna; Van Duijnen, Piet Th.

    2017-04-01

    The paper reports the results of a theoretical study of the conformational behavior and basicity of biogenic amine agmatine. The complexes modelling of agmatine - protein interaction are also under scrutiny of our investigation using the Becke3LYP and B97D levels of the density functional theory. The relative stabilities (Gibbs energies) of individual complexes are by both DFT methods described equally. Hydration has a dramatic effect on the hydrogen bonded complexes studied. The pairing acidic carboxylate group with different agmatine species resulted in charged hydrogen bond complexes containing negatively charged acetate species acting as proton acceptors.

  15. Agmatine promotes the migration of murine brain endothelial cells via multiple signaling pathways.

    Science.gov (United States)

    Jung, Hyun-Joo; Jeon, Yong-Heui; Bokara, Kiran Kumar; Koo, Bon-Nyeo; Lee, Won Taek; Park, Kyung Ah; Lee, Jong-Eun

    2013-01-17

    The combination of adhesion and migration of endothelial cells (ECs) is an integral process for evolution, organization, repair and vessel formation in living organisms. Agmatine, a polycationic amine existing in brain, has been investigated to exert neuroprotective effects. Up to date, there are no studies reporting that agmatine modulates murine brain endothelial (bEnd.3) cells migration. In the present study, we intend to investigate the role of agmatine in bEnd.3 cells migration and the molecular mechanism mediating this action. The effect of agmatine on the bEnd.3 cells migration was examined by migration assay, and the mechanism involved for this effect was investigated by western blot analysis and NO contents measurements. Agmatine treatment (50, 100 and 200 μM) significantly accelerated bEnd.3 cells migration in a concentration-dependent manner. Western blotting revealed that agmatine treatment significantly induced vascular endothelial growth factor (VEGF), VEGF receptor 2 (Flk-1/KDR or VEGFR2), phosphatidylinositol 3-kinase (PI3K), Akt/protein kinase B (also known as PKB, PI3K downstream effector protein), endothelial nitric oxide synthase (eNOS) nitric oxide (NO; product by eNOS) and intercellular adhesion molecule 1 (ICAM-1) expressions during bEnd.3 cells migration. The expression of ICAM-1 and migration of bEnd.3 cells, induced by agmatine, were significantly attenuated by treatment of wortmannin, a specific PI3K inhibitor. Taken together, we provide the first evidence that activation of VEGF/VEGFR2 and the consequential PI3K/Akt/eNOS/NO/ICAM-1 signaling pathways are serial events, through which the treatment of agmatine could lead to bEnd.3 cells migration. Copyright © 2012 Elsevier Inc. All rights reserved.

  16. An agmatine-inducible system for the expression of recombinant proteins in Enterococcus faecalis.

    Science.gov (United States)

    Linares, Daniel M; Perez, Marta; Ladero, Victor; Del Rio, Beatriz; Redruello, Begoña; Martin, M Cruz; Fernandez, María; Alvarez, Miguel A

    2014-12-04

    Scientific interest in Enterococcus faecalis has increased greatly over recent decades. Some strains are involved in food fermentation and offer health benefits, whereas others are vancomycin-resistant and cause infections that are difficult to treat. The limited availability of vectors able to express cloned genes efficiently in E. faecalis has hindered biotechnological studies on the bacterium's regulatory and pathogenicity-related genes. The agmatine deiminase (AGDI) pathway of E. faecalis, involved in the conversion of agmatine into putrescine, is driven by a response inducer gene aguR. This study describes that the exposure to the induction factor (agmatine) results in the transcription of genes under the control of the aguB promoter, including the aguBDAC operon. A novel E. faecalis expression vector, named pAGEnt, combining the aguR inducer gene and the aguB promoter followed by a cloning site and a stop codon was constructed. pAGEnt was designed for the overexpression and purification of a protein fused to a 10-amino-acid His-tag at the C-terminus. The use of GFP as a reporter of gene expression in E. faecalis revealed that under induction with 60 mM agmatine, fluorescence reached 40 arbitrary units compared to 0 in uninduced cells. pAGEnt vector can be used for the overexpression of recombinant proteins under the induction of agmatine in E. faecalis, with a close correlation between agmatine concentration and fluorescence when GFP was used as reporter.

  17. Agmatine attenuates chronic unpredictable mild stress induced behavioral alteration in mice.

    Science.gov (United States)

    Taksande, Brijesh G; Faldu, Dharmesh S; Dixit, Madhura P; Sakaria, Jay N; Aglawe, Manish M; Umekar, Milind J; Kotagale, Nandkishor R

    2013-11-15

    Chronic stress exposure and resulting dysregulation of the hypothalamic pituitary adrenal axis develops susceptibility to variety of neurological and psychiatric disorders. Agmatine, a putative neurotransmitter has been reported to be released in response to various stressful stimuli to maintain the homeostasis. Present study investigated the role of agmatine on chronic unpredictable mild stress (CUMS) induced behavioral and biochemical alteration in mice. Exposure of mice to CUMS protocol for 28 days resulted in diminished performance in sucrose preference test, splash test, forced swim test and marked elevation in plasma corticosterone levels. Chronic agmatine (5 and 10 mg/kg, ip, once daily) treatment started on day-15 and continued till the end of the CUMS protocol significantly increased sucrose preference, improved self-care and motivational behavior in the splash test and decreased duration of immobility in the forced swim test. Agmatine treatment also normalized the elevated corticosterone levels and prevented the body weight changes in chronically stressed animals. The pharmacological effect of agmatine was comparable to selective serotonin reuptake inhibitor, fluoxetine (10mg/kg, ip). Results of present study clearly demonstrated the anti-depressant like effect of agmatine in chronic unpredictable mild stress induced depression in mice. Thus the development of drugs based on brain agmatinergic modulation may represent a new potential approach for the treatment of stress related mood disorders like depression. © 2013 Published by Elsevier B.V.

  18. Pre-treatment with cardamonin protects against cisplatin-induced nephrotoxicity in rats: Impact on NOX-1, inflammation and apoptosis

    International Nuclear Information System (INIS)

    El-Naga, Reem N.

    2014-01-01

    Cisplatin is an effective anti-cancer drug; however, its clinical use is usually associated with nephrotoxicity as a dose-limiting side effect. Several molecular mechanisms have been found to be involved in this nephrotoxicity such as oxidative stress, inflammation and apoptosis. The aim of this study was to explore the potential nephroprotective effect of cardamonin, a flavone found in Alpinia plant, in a rat model of cisplatin-induced nephrotoxicity. The possible mechanisms underlying this nephroprotective effect were investigated. Cardamonin was given at two different doses; 10 and 30 mg/kg orally for two weeks, starting one week before giving a single nephrotoxic dose of cisplatin (7 mg/kg). Acute nephrtoxicity was evident by significantly increased blood urea nitrogen and serum creatinine levels. Also, cisplatin increased lipid peroxidation and depleted reduced glutathione level and superoxide dismutase. Additionally, cisplatin showed a marked pro-inflammatory response as evidenced by significant increase in tissue levels of IL-1β, TNF-α, NF-kB, iNOS, ICAM-1 and MCP-1. Pre-treatment with cardamonin significantly attenuated the nephrotoxic effects, oxidative stress and inflammation induced by cisplatin, in a dose-dependent manner. Also, cardamonin decreased caspase-3 expression and Bax/Bcl-2 ratio as compared to cisplatin group. Besides, cradamonin reversed cisplatin-induced decrease in EGF. Furthermore, up-regulation of NOX-1 was found to be involved in cisplatin-induced nephrotoxicity and its expression was significantly reduced by cardamonin. Histopathological examination further confirmed the nephroprotective effect of cardamonin. Moreover, pre-treatment with subtoxic concentration of cardamonin has significantly enhanced cisplatin cytotoxic activity in four different human cancer cell lines; hela, hepG2, PC3 and HCT116 cancer cell lines. In conclusion, these findings suggest that cardamonin improves therapeutic index of cisplatin and that NOX-1 is

  19. Pre-treatment with cardamonin protects against cisplatin-induced nephrotoxicity in rats: Impact on NOX-1, inflammation and apoptosis

    Energy Technology Data Exchange (ETDEWEB)

    El-Naga, Reem N., E-mail: reemelnaga@hotmail.com

    2014-01-01

    Cisplatin is an effective anti-cancer drug; however, its clinical use is usually associated with nephrotoxicity as a dose-limiting side effect. Several molecular mechanisms have been found to be involved in this nephrotoxicity such as oxidative stress, inflammation and apoptosis. The aim of this study was to explore the potential nephroprotective effect of cardamonin, a flavone found in Alpinia plant, in a rat model of cisplatin-induced nephrotoxicity. The possible mechanisms underlying this nephroprotective effect were investigated. Cardamonin was given at two different doses; 10 and 30 mg/kg orally for two weeks, starting one week before giving a single nephrotoxic dose of cisplatin (7 mg/kg). Acute nephrtoxicity was evident by significantly increased blood urea nitrogen and serum creatinine levels. Also, cisplatin increased lipid peroxidation and depleted reduced glutathione level and superoxide dismutase. Additionally, cisplatin showed a marked pro-inflammatory response as evidenced by significant increase in tissue levels of IL-1β, TNF-α, NF-kB, iNOS, ICAM-1 and MCP-1. Pre-treatment with cardamonin significantly attenuated the nephrotoxic effects, oxidative stress and inflammation induced by cisplatin, in a dose-dependent manner. Also, cardamonin decreased caspase-3 expression and Bax/Bcl-2 ratio as compared to cisplatin group. Besides, cradamonin reversed cisplatin-induced decrease in EGF. Furthermore, up-regulation of NOX-1 was found to be involved in cisplatin-induced nephrotoxicity and its expression was significantly reduced by cardamonin. Histopathological examination further confirmed the nephroprotective effect of cardamonin. Moreover, pre-treatment with subtoxic concentration of cardamonin has significantly enhanced cisplatin cytotoxic activity in four different human cancer cell lines; hela, hepG2, PC3 and HCT116 cancer cell lines. In conclusion, these findings suggest that cardamonin improves therapeutic index of cisplatin and that NOX-1 is

  20. Acute orexigenic effect of agmatine involves interaction between central α2-adrenergic and GABAergic receptors.

    Science.gov (United States)

    Taksande, Brijesh Gulabrao; Sharma, Omi; Aglawe, Manish Manohar; Kale, Mayur Bhimrao; Gawande, Dinesh Yugraj; Umekar, Milind Janraoji; Kotagale, Nandkishor Ramdas

    2017-09-01

    Agmatine and GABA have been abundantly expressed in brain nuclei involved in regulation of energy homeostasis and promoting stimulation of food intake in rodents. However, their mutual interaction, if any, in the elicitation of feeding behavior is largely remains unclear. The current study provides experimental evidence for the possible interaction of agmatine, adrenergic and GABAergic systems in stimulation of feeding in satiated rats. Satiated rats fitted with intracerebroventricular (i.c.v.) cannulae and were administered agmatine, alone or jointly with (a) GABA A receptor agonist, muscimol, diazepam or antagonist bicuculline and flumazenil, GABA A positive modulator, allopregnanolone or negative modulator of GABA A receptor, dehydroepiandrosterone (b) In view of the high affinity of agmatine for α 2 -adrenoceptors and the close association between α 2 -adrenoceptors and GABAergic system, the effect of their modulators on feeding elicited by agmatine/GABAergic agonists were also examined. I.c.v. administration of agmatine (40-80μg/rat) induces the significant orexigenic effect in satiated rats. The orexigenic effect of agmatine was potentiated by muscimol (25ng/rat, i.c.v.); diazepam (0.5mg/kg, i.p.); allopregnanolone (0.5mg/kg, s.c.) and blocked by bicuculline (1mg/kg, i.p.) and dehydroepiandrosterone (4mg/kg,s.c.). However, it remained unaffected in presence of flumazenil (25ng/rat, i.c.v.). The orexigenic effect of agmatine and GABAergic agonists was potentiated by a α 2 -adrenoceptors agonist, clonidine (10ng/rat, i.c.v.) and blocked by its antagonist, yohimbine (5μg/rat, i.c.v.). Yohimbine also blocked the hyperphagic effect elicited by ineffective dose combination of agmatine (5μg/rat, i.c.v.) with muscimol (25ng/rat, i.c.v.) or diazepam (0.5mg/kg, i.p.) or allopregnanolone (0.5mg/kg,s.c.). The results of the present study suggest that agmatine induced α 2 -adrenoceptors activation might facilitate GABAergic activity to stimulate food intake in

  1. Region-specific changes in presynaptic agmatine and glutamate levels in the aged rat brain.

    Science.gov (United States)

    Jing, Y; Liu, P; Leitch, B

    2016-01-15

    During the normal aging process, the brain undergoes a range of biochemical and structural alterations, which may contribute to deterioration of sensory and cognitive functions. Age-related deficits are associated with altered efficacy of synaptic neurotransmission. Emerging evidence indicates that levels of agmatine, a putative neurotransmitter in the mammalian brain, are altered in a region-specific manner during the aging process. The gross tissue content of agmatine in the prefrontal cortex (PFC) of aged rat brains is decreased whereas levels in the temporal cortex (TE) are increased. However, it is not known whether these changes in gross tissue levels are also mirrored by changes in agmatine levels at synapses and thus could potentially contribute to altered synaptic function with age. In the present study, agmatine levels in presynaptic terminals in the PFC and TE regions (300 terminals/region) of young (3month; n=3) and aged (24month; n=3) brains of male Sprague-Dawley rats were compared using quantitative post-embedding immunogold electron-microscopy. Presynaptic levels of agmatine were significantly increased in the TE region (60%; pagmatine and glutamate were co-localized in the same synaptic terminals, and quantitative analyses revealed significantly reduced glutamate levels in agmatine-immunopositive synaptic terminals in both regions in aged rats compared to young animals. This study, for the first time, demonstrates differential effects of aging on agmatine and glutamate in the presynaptic terminals of PFC and TE. Future research is required to understand the functional significance of these changes and the underlying mechanisms. Copyright © 2015 IBRO. Published by Elsevier Ltd. All rights reserved.

  2. Sub-chronic agmatine treatment modulates hippocampal neuroplasticity and cell survival signaling pathways in mice.

    Science.gov (United States)

    Freitas, Andiara E; Bettio, Luis E B; Neis, Vivian B; Moretti, Morgana; Ribeiro, Camille M; Lopes, Mark W; Leal, Rodrigo B; Rodrigues, Ana Lúcia S

    2014-11-01

    Agmatine is an endogenous neuromodulator which, based on animal and human studies, is a putative novel antidepressant drug. In this study, we investigated the ability of sub-chronic (21 days) p.o. agmatine administration to produce an antidepressant-like effect in the tail suspension test and examined the hippocampal cell signaling pathways implicated in such an effect. Agmatine at doses of 0.01 and 0.1 mg/kg (p.o.) produced a significant antidepressant-like effect in the tail suspension test and no effect in the open-field test. Additionally, agmatine (0.001-0.1 mg/kg, p.o.) increased the phosphorylation of protein kinase A substrates (237-258% of control), protein kinase B/Akt (Ser(473)) (116-127% of control), glycogen synthase kinase-3β (Ser(9)) (110-113% of control), extracellular signal-regulated kinases 1/2 (119-137% and 121-138% of control, respectively) and cAMP response elements (Ser(133)) (127-152% of control), and brain-derived-neurotrophic factor (137-175% of control) immunocontent in a dose-dependent manner in the hippocampus. Agmatine (0.001-0.1 mg/kg, p.o.) also reduced the c-jun N-terminal kinase 1/2 phosphorylation (77-71% and 65-51% of control, respectively). Neither protein kinase C nor p38(MAPK) phosphorylation was altered under any experimental conditions. Taken together, the present study extends the available data on the mechanisms that underlie the antidepressant action of agmatine by showing an antidepressant-like effect following sub-chronic administration. In addition, our results are the first to demonstrate the ability of agmatine to elicit the activation of cellular signaling pathways associated with neuroplasticity/cell survival and the inhibition of signaling pathways associated with cell death in the hippocampus. Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. Long-term (5 years), high daily dosage of dietary agmatine--evidence of safety: a case report.

    Science.gov (United States)

    Gilad, Gad M; Gilad, Varda H

    2014-11-01

    There is presently a great interest in the therapeutic potential of agmatine, decarboxylated arginine, for various diseases. Recent clinical studies have already shown that oral agmatine sulfate given for up to 3 weeks provides a safe and, as compared with current therapeutics, more effective treatment for neuropathic pain. These studies have ushered in the use of dietary agmatine as a nutraceutical. However, in view of information paucity, assessment of long-term safety of oral agmatine treatment is now clearly required. The authors of this report undertook to assess their own health status during ongoing consumption of a high daily dosage of oral agmatine over a period of 4-5 years. A daily dose of 2.67 g agmatine sulfate was encapsulated in gelatin capsules; the regimen consists of six capsules daily, each containing 445 mg, three in the morning and three in the evening after meals. Clinical follow-up consists of periodic physical examinations and laboratory blood and urine analyses. All measurements thus far remain within normal values and good general health status is sustained throughout the study period, up to 5 years. This case study shows for the first time that the recommended high dosage of agmatine may be consumed for at least 5 years without evidence of any adverse effects. These initial findings are highly important as they provide significant evidence for the extended long-term safety of a high daily dosage of dietary agmatine--a cardinal advantage for its utility as a nutraceutical.

  4. Agmatine suppresses peripheral sympathetic tone by inhibiting N-type Ca(2+) channel activity via imidazoline I2 receptor activation.

    Science.gov (United States)

    Kim, Young-Hwan; Jeong, Ji-Hyun; Ahn, Duck-Sun; Chung, Seungsoo

    2016-08-26

    Agmatine, a putative endogenous ligand of imidazoline receptors, suppresses cardiovascular function by inhibiting peripheral sympathetic tone. However, the molecular identity of imidazoline receptor subtypes and its cellular mechanism underlying the agmatine-induced sympathetic suppression remains unknown. Meanwhile, N-type Ca(2+) channels are important for the regulation of NA release in the peripheral sympathetic nervous system. Therefore, it is possible that agmatine suppresses NA release in peripheral sympathetic nerve terminals by inhibiting Ca(2+) influx through N-type Ca(2+) channels. We tested this hypothesis by investigating agmatine effect on electrical field stimulation (EFS)-evoked contraction and NA release in endothelium-denuded rat superior mesenteric arterial strips. We also investigated the effect of agmatine on the N-type Ca(2+) current in superior cervical ganglion (SCG) neurons in rats. Our study demonstrates that agmatine suppresses peripheral sympathetic outflow via the imidazoline I2 receptor in rat mesenteric arteries. In addition, the agmatine-induced suppression of peripheral vascular sympathetic tone is mediated by modulating voltage-dependent N-type Ca(2+) channels in sympathetic nerve terminals. These results suggest a potential cellular mechanism for the agmatine-induced suppression of peripheral sympathetic tone. Furthermore, they provide basic and theoretical information regarding the development of new agents to treat hypertension. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. Agmatine attenuates acquisition but not the expression of ethanol conditioned place preference in mice: a role for imidazoline receptors.

    Science.gov (United States)

    Sameer, Shaikh M; Chakraborty, Suwarna S; Ugale, Rajesh R

    2013-04-01

    The present study investigated the effect of agmatine on acquisition and expression of ethanol conditioned place preference (CPP) and its modulation by imidazoline agents. Swiss albino mice were treated intraperitoneally with saline or agmatine (20-40 mg/kg) before injection of ethanol (1.25 mg/kg) during conditioning days or on a test day (20-120 mg/kg), to observe the effect on acquisition or expression of CPP, respectively. Agmatine inhibited the acquisition but not the expression of ethanol CPP. Furthermore, both the I₁ receptor antagonist, efaroxan (9 mg/kg) and the I₂ receptor antagonist, BU224 (5 mg/kg) attenuated the agmatine-induced inhibition of the ethanol CPP acquisition. In contrast, the I₂ receptor agonist, 2-BFI (5 mg/kg) and I₁ receptor agonist, moxonidine (0.4 mg/kg) alone, or a combination of their subeffective doses, significantly attenuated the effect of agmatine (20 mg/kg) on acquisition of ethanol CPP. Agmatine or imidazoline agents alone produced neither place preference nor aversion, and at the doses used in the present study did not affect locomotor activity. Thus, agmatine attenuates the acquisition of ethanol CPP at least in part by imidazoline (I₁ or I₂) receptors. In future studies, agmatine or agents acting at the imidazoline receptors could be explored for their therapeutic potential in ethanol dependence.

  6. Immunomodulatory pretreatment with Kalanchoe pinnata extract and its quercitrin flavonoid effectively protects mice against fatal anaphylactic shock.

    Science.gov (United States)

    Cruz, E A; Da-Silva, S A G; Muzitano, M F; Silva, P M R; Costa, S S; Rossi-Bergmann, B

    2008-12-10

    Previously, we reported the immunosuppressive action of the aqueous extract of Kalanchoe pinnata (Kp) in mice. In the present study, we report on the protective effect of Kp in fatal anaphylactic shock, likewise a Th2-driven immunopathology, and the identification of its active component. Mice daily treated with oral Kp during hypersensitization with ovalbumin were all protected against death when challenged with the allergen, as compared with the 100% mortality in the untreated group. A single intraperitoneal dose 3 h prior to challenge was partially effective. Oral protection was accompanied by a reduced production of OVA-specific IgE antibodies, reduced eosinophilia, and impaired production of the IL-5, IL-10 and TNF-alpha cytokines. In vitro, Kp prevented antigen-induced mast cell degranulation and histamine release. Oral treatment with the quercitrin flavonoid isolated from Kp prevented fatal anaphylaxis in 75% of the animals. These findings indicate that oral treatment with Kp effectively downmodulates pro-anaphylactic inducing immune responses. Protection achieved with quercitrin, although not maximal, suggests that this flavonoid is a critical component of Kp extract against this extreme allergic reaction.

  7. Pretreatment with remifentanil protects against the reduced-intestinal contractility related to the ischemia and reperfusion injury in rat

    Directory of Open Access Journals (Sweden)

    Hale Sayan-Ozacmak

    2015-12-01

    Full Text Available BACKGROUND AND OBJECTIVES: Serious functional and structural alterations of gastrointestinal tract are observed in failure of blood supply, leading to gastrointestinal dismotility. Activation of opioid receptors provides cardioprotective effect against ischemia-reperfusion (I/R injury. The aim of the present study was to determine whether or not remifentanil could reduce I/R injury of small intestine. METHODS: Male Wistar Albino rats were subjected to mesenteric ischemia (30 min followed by reperfusion (3 h. Four groups were designed: sham control; remifentanil alone; I/R control; and remifentanil + I/R. Animals in remifentanil + I/R group were subjected to infusion of remifentanil (2 ug kg-1 min-1 for 60 min, half of which started before inducing ischemia. Collecting the ileum tissues, evaluation of damage was based on contractile responses to carbachol, levels of lipid peroxidation and neutrophil infiltration, and observation of histopathological features in intestinal tissue. RESULTS: Following reperfusion, a significant decrease in carbachol-induced contractile response, a remarkable increase in both lipid peroxidation and neutrophil infiltration, and a significant injury in mucosa were observed. An average contractile response of remifentanil + I/R group was significantly different from that of the I/R group. Lipid peroxidation and neutrophil infiltration were also significantly suppressed by the treatment. The tissue samples of the I/R group were grade 4 in histopathological evaluation. In remifentanil + I/R group, on the other hand, the mucosal damage was moderate, staging as grade 1. CONCLUSIONS: The pretreatment with remifentanil can attenuate the intestinal I/R injury at a remarkable degree possibly by lowering lipid peroxidation and leukocyte infiltration.

  8. Depressive-like behavior induced by tumor necrosis factor-α is abolished by agmatine administration.

    Science.gov (United States)

    Neis, Vivian Binder; Manosso, Luana Meller; Moretti, Morgana; Freitas, Andiara E; Daufenbach, Juliana; Rodrigues, Ana Lúcia S

    2014-03-15

    Agmatine, an endogenous cationic amine, has been shown to exert antidepressant-like effects. This study investigated the ability of agmatine administered orally to abolish the depressive-like behavior induced by the administration of the pro-inflammatory cytokine, tumor necrosis factor (TNF-α) in mice. In control animals, agmatine (0.001, 0.01, 0.1, and 1 mg/kg) reduced the immobility time in the tail suspension test (TST). Acute administration of TNF-α (0.001 fg/mouse, i.c.v.) increased immobility time in the TST, indicative of a depressive-like behavior, and agmatine (0.0001, 0.1, and 1 mg/kg) prevented this effect. Additionally, we examined the effects of the combined administration of sub-effective doses of agmatine with antidepressants, the NMDA receptor antagonist MK-801 and the neuronal nitric oxide synthase inhibitor 7-nitroindazole (7-NI) in mice exposed to either TNF-α or saline. In control mice, administration of a sub-effective dose of agmatine (0.0001 mg/kg) combined with sub-effective doses of either fluoxetine (5 mg/kg, p.o.), imipramine (0.1 mg/kg, p.o.), bupropion (1 mg/kg, p.o.), MK-801 (0.001 mg/kg, p.o.) or 7-NI (25 mg/kg, i.p.) produced a synergistic antidepressant-like effect in the TST. All these administrations prevented the increased immobility time induced by TNF-α. The effect of agmatine in the TNF-α model of depression appears to be associated, at least partially, with an activation of the monoaminergic systems and inhibition of NMDA receptors and nitric oxide synthesis, although converging signal transduction pathways that may underlie the effect of agmatine should be further investigated. This set of results indicates that agmatine may constitute a new therapeutic alternative for the treatment of depression associated with inflammation. Copyright © 2014 Elsevier B.V. All rights reserved.

  9. Agmatine Attenuates Brain Edema and Apoptotic Cell Death after Traumatic Brain Injury.

    Science.gov (United States)

    Kim, Jae Young; Lee, Yong Woo; Kim, Jae Hwan; Lee, Won Taek; Park, Kyung Ah; Lee, Jong Eun

    2015-07-01

    Traumatic brain injury (TBI) is associated with poor neurological outcome, including necrosis and brain edema. In this study, we investigated whether agmatine treatment reduces edema and apoptotic cell death after TBI. TBI was produced by cold injury to the cerebral primary motor cortex of rats. Agmatine was administered 30 min after injury and once daily until the end of the experiment. Animals were sacrificed for analysis at 1, 2, or 7 days after the injury. Various neurological analyses were performed to investigate disruption of the blood-brain barrier (BBB) and neurological dysfunction after TBI. To examine the extent of brain edema after TBI, the expression of aquaporins (AQPs), phosphorylation of mitogen-activated protein kinases (MAPKs), and nuclear translocation of nuclear factor-κB (NF-κB) were investigated. Our findings demonstrated that agmatine treatment significantly reduces brain edema after TBI by suppressing the expression of AQP1, 4, and 9. In addition, agmatine treatment significantly reduced apoptotic cell death by suppressing the phosphorylation of MAPKs and by increasing the nuclear translocation of NF-κB after TBI. These results suggest that agmatine treatment may have therapeutic potential for brain edema and neural cell death in various central nervous system diseases.

  10. Effects of prolonged agmatine treatment in aged male Sprague-Dawley rats.

    Science.gov (United States)

    Rushaidhi, M; Zhang, H; Liu, P

    2013-03-27

    Increasing evidence suggests that altered arginine metabolism contributes to cognitive decline during ageing. Agmatine, decarboxylated arginine, has a variety of pharmacological effects, including the modulation of behavioural function. A recent study demonstrated the beneficial effects of short-term agmatine treatment in aged rats. The present study investigated how intraperitoneal administration of agmatine (40mg/kg, once daily) over 4-6weeks affected behavioural function and neurochemistry in aged Sprague-Dawley rats. Aged rats treated with saline displayed significantly reduced exploratory activity in the open field, impaired spatial learning and memory in the water maze and object recognition memory relative to young rats. Prolonged agmatine treatment improved animals' performance in the reversal test of the water maze and object recognition memory test, and significantly suppressed age-related elevation in nitric oxide synthase activity in the dentate gyrus of the hippocampus and prefrontal cortex. However, this prolonged supplementation was unable to improve exploratory activity and spatial reference learning and memory in aged rats. These findings further demonstrate that exogenous agmatine selectively improves behavioural function in aged rats. Copyright © 2013 IBRO. Published by Elsevier Ltd. All rights reserved.

  11. Dietary broccoli protects against fatty liver development but not against progression of liver cancer in mice pretreated with diethylnitrosamine

    Science.gov (United States)

    Chen, Yung-Ju; Myracle, Angela D.; Wallig, Matthew A.; Jeffery, Elizabeth H.

    2016-01-01

    Western-style high fat, high sugar diets are associated with non-alcoholic fatty liver disease (NAFLD) and increased liver cancer risk. Sulforaphane from broccoli may protect against these. Previously we initiated broccoli feeding to mice prior to exposure to the hepatocarcinogen diethylnitrosamine (DEN), and saw protection against NAFLD and liver cancer. Here we administered DEN to unweaned mice, initiating broccoli feeding two weeks later, to determine if broccoli protects against cancer progression. Specifically, male 15-day-old C57BL/6J mice were given DEN and placed on a Western or Western+10%Broccoli diet from the age of 4 weeks through 7 months. Dietary broccoli decreased hepatic triacylglycerols, NAFLD, liver damage and tumour necrosis factor by month 5 without changing body weight or relative liver weight, but did not slow carcinogenesis, seen in 100% of mice. We conclude that broccoli, a good source of sulforaphane, slows progression of hepatic lipidosis, but not tumourigenesis in this robust model. PMID:27672403

  12. Agmatine, an endogenous ligand at imidazoline binding sites, does not antagonize the clonidine-mediated blood pressure reaction

    Science.gov (United States)

    Raasch, Walter; Schäfer, Ulrich; Qadri, Fatimunnisa; Dominiak, Peter

    2002-01-01

    Since agmatine has been identified as a clonidine displacing substance (CDS), the aim of this study was to investigate whether agmatine can mimic CDS-induced cardiovascular reactions in organ bath experiments, pithed spontaneously hypertensive rats (SHR) and anaesthetized SHR.Intravenously-administered agmatine significantly reduced the blood pressure and heart rate of anaesthetized SHR at doses higher than 1 and 3 mg kg−1, respectively. These effects are probably mediated via central mechanisms, since there was an approximate 8 fold rightward shift of the dose-response curve in the pithed SHR (indicating a weakened cardiovascular effect). Moreover, in organ bath experiments, agmatine failed to alter the contractility of intact or endothelium-denuded aortal rings. When agmatine was administered i.c.v. to anaesthetized SHR, blood pressure was increased without any alteration of heart rate, whereas blood pressure was unchanged and heart rate was increased after injection into the 4th brain ventricle. This suggests that haemodynamic reaction patterns after central application are related to distinct influences on central cardiovascular mechanisms.Agmatine reduces noradrenaline release in pithed SHR while α2-adrenoceptors are irreversibly blocked with phenoxybenzamine, but not while I1-binding sites are selectively blocked with AGN192403. This suggests that agmatine may modulate noradrenaline release in the same way that clonidine does, i.e. via imidazoline binding sites; this involves a reduction in sympathetic tone which in turn reduces blood pressure and heart rate.Finally, CDS-like cardiovascular activity appears not to be due to agmatine, since (i) blood pressure in anaesthetized SHR is decreased by agmatine and clonidine, and (ii) agmatine did not antagonize the blood pressure reaction to clonidine in pithed or anaesthetized SHR. PMID:11834614

  13. Implementation of the agmatine-controlled expression system for inducible gene expression in Lactococcus lactis.

    Science.gov (United States)

    Linares, Daniel M; Alvarez-Sieiro, Patricia; del Rio, Beatriz; Ladero, Victor; Redruello, Begoña; Martin, Ma Cruz; Fernandez, Maria; Alvarez, Miguel A

    2015-12-30

    Lactococcus lactis has been safely consumed in fermented foods for millennia. This Gram-positive bacterium has now become of industrial importance as an expression host for the overproduction of lipopolysaccharide-free recombinant proteins used as food ingredients, therapeutic proteins and biotechnological enzymes. This paper reports an agmatine-controlled expression (ACE) system for L. lactis, comprising the lactococcal agmatine-sensor/transcriptional activator AguR and its target promoter P(aguB). The usefulness and efficiency of this system was checked via the reporter gene gfp and by producing PEP (Myxococcus xanthus prolyl-endopeptidase), an enzyme of biomedical interest able to degrade the immunotoxic peptides produced during the gastrointestinal breakdown of gluten. The ACE system developed in this work was suitable for the efficient expression of the functional recombinant proteins GFP and PEP. The expression system was tightly regulated by the agmatine concentration and allowed high protein production without leakiness.

  14. Radiation pre-treatment of seed imparts metabolic stability and quality protection during storage under accelerated aging

    International Nuclear Information System (INIS)

    Sumedha; Singh, Bhupinder; Singhal, R.K.

    2014-01-01

    Quality of seed is known to deteriorate due to unfavoured temperature and relative humidity during accelerated aging. Protecting the seed quality during storage is thus a priority challenge for the seed industry till the seeds end up with the end user. Gamma radiation treatment has been shown to improve source to sink transport of photosynthates during terminal heat stress in cereals. An experiment was conducted to measure seed irradiation induced biochemical changes in groundnut cultivar TG-37A stored under accelerated aging at 45±2 ℃ and 95-100 % humidity for 0, 5, 10, 15, 20 and 40 days to aging. The gamma irradiation doses were control (0), 0.005, 0.025, 0.1, 0.5 and 1.0 kGy. Seed samples were periodically evaluated for oil and fatty acid profile by the soxhlet extraction method and gas chromatography mass spectroscopy respectively. Here alike earlier studies variation in fatty acid profile of seed was used as an indicator of seed health under harsh storage conditions of accelerated aging. In the majority of plant species having oil rich seeds, the lipids that are at risk of auto-oxidation contain oleic (18:1), linoleic (18:2) and linolenic (18:3) fatty acid chain. Degree of unsaturation has a significant influence on degree of degradation. Decreased total lipid content in aged sunflower seeds have been reported. Auto-oxidation of unsaturated fatty acids was noticed, especially for linoleic acid in seed of oil crop after seven years of storage. Our results showed radiation treatment did not cause any significant change in oleic (C18:1), linoleic acids (C18:2) and linolenic (C18:3) acid content of seeds. This shows that gamma radiation essentially slows down the lipid peroxidation which essentially protects membrane permeability and reduces the rate of seed deterioration at high temperature and RH. Radiation treatment imparts metabolic stability in seeds during storage under accelerated aging conditions. (author)

  15. Agmatine induced NO dependent rat mesenteric artery relaxation and its impairment in salt-sensitive hypertension.

    Science.gov (United States)

    Gadkari, Tushar V; Cortes, Natalie; Madrasi, Kumpal; Tsoukias, Nikolaos M; Joshi, Mahesh S

    2013-11-30

    l-Arginine and its decarboxylated product, agmatine are important mediators of NO production and vascular relaxation. However, the underlying mechanisms of their action are not understood. We have investigated the role of arginine and agmatine in resistance vessel relaxation of Sprague-Dawley (SD) and Dahl salt-sensitive hypertensive rats. Second or 3rd-order mesenteric arterioles were cannulated in an organ chamber, pressurized and equilibrated before perfusing intraluminally with agonists. The vessel diameters were measured after mounting on the stage of a microscope fitted with a video camera. The gene expression in Dahl rat vessel homogenates was ascertained by real-time PCR. l-Arginine initiated relaxations (EC50, 5.8±0.7mM; n=9) were inhibited by arginine decarboxylase (ADC) inhibitor, difluoromethylarginine (DFMA) (EC50, 18.3±1.3mM; n=5) suggesting that arginine-induced vessel relaxation was mediated by agmatine formation. Agmatine relaxed the SD rat vessels at significantly lower concentrations (EC50, 138.7±12.1μM; n=22), which was compromised by l-NAME (l-N(G)-nitroarginine methyl ester, an eNOS inhibitor), RX821002 (α-2 AR antagonist) and pertussis toxin (G-protein inhibitor). The agmatine-mediated vessel relaxation from high salt Dahl rats was abolished as compared to that from normal salt rats (EC50, 143.9±23.4μM; n=5). The α-2A AR, α-2B AR and eNOS mRNA expression was downregulated in mesenteric arterioles of high-salt treated Dahl hypertensive rats. These findings demonstrate that agmatine facilitated the relaxation via activation of α-2 adrenergic G-protein coupled receptor and NO synthesis, and this pathway is compromised in salt-sensitive hypertension. Copyright © 2013 Elsevier Inc. All rights reserved.

  16. Chronic agmatine treatment prevents behavioral manifestations of nicotine withdrawal in mice.

    Science.gov (United States)

    Kotagale, Nandkishor R; Chopde, Chandrabhan T; Umekar, Milind J; Taksande, Brijesh G

    2015-05-05

    Smoking cessation exhibits an aversive withdrawal syndrome characterized by both increases in somatic signs and affective behaviors including anxiety and depression. In present study, abrupt withdrawal of daily nicotine injections (2mg/kg, s.c., four times daily, for 10 days) significantly increased somatic signs viz. rearing, grooming, jumping, genital licking, leg licking, head shakes with associated depression (increased immobility in forced swim test) as well as anxiety (decreased the number of entries and time spent in open arm in elevated plus maze) in nicotine dependent animals. The peak effect was observed at 24h time point of nicotine withdrawal. Repeated administration of agmatine (40-80µg/mouse, i.c.v.) before the first daily dose of nicotine from day 5 to 10 attenuated the elevated scores of somatic signs and abolished the depression and anxiety like behavior induced by nicotine withdrawal in dependent animals. However, in separate groups, its acute administration 30min before behavior analysis of nicotine withdrawal was ineffective. This result clearly shows the role of agmatine in development of nicotine dependence and its withdrawal. In extension to behavioral experiments, brain agmatine analyses, carried out at 24h time point of nicotine withdrawal demonstrated marked decrease in basal brain agmatine concentration as compared to control animals. Taken together, these data support the role of agmatine as common biological substrate for somatic signs and affective symptoms of nicotine withdrawal. This data may project therapies based on agmatine in anxiety, depression and mood changes associated with tobacco withdrawal. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Lignocellulosic Biomass Pretreatment Using AFEX

    Science.gov (United States)

    Balan, Venkatesh; Bals, Bryan; Chundawat, Shishir P. S.; Marshall, Derek; Dale, Bruce E.

    Although cellulose is the most abundant organic molecule, its susceptibility to hydrolysis is restricted due to the rigid lignin and hemicellulose protection surrounding the cellulose micro fibrils. Therefore, an effective pretreatment is necessary to liberate the cellulose from the lignin-hemicellulose seal and also reduce cellulosic crystallinity. Some of the available pretreatment techniques include acid hydrolysis, steam explosion, ammonia fiber expansion (AFEX), alkaline wet oxidation, and hot water pretreatment. Besides reducing lignocellulosic recalcitrance, an ideal pretreatment must also minimize formation of degradation products that inhibit subsequent hydrolysis and fermentation. AFEX is an important pretreatment technology that utilizes both physical (high temperature and pressure) and chemical (ammonia) processes to achieve effective pretreatment. Besides increasing the surface accessibility for hydrolysis, AFEX promotes cellulose decrystallization and partial hemicellulose depolymerization and reduces the lignin recalcitrance in the treated biomass. Theoretical glucose yield upon optimal enzymatic hydrolysis on AFEX-treated corn stover is approximately 98%. Furthermore, AFEX offers several unique advantages over other pretreatments, which include near complete recovery of the pretreatment chemical (ammonia), nutrient addition for microbial growth through the remaining ammonia on pretreated biomass, and not requiring a washing step during the process which facilitates high solid loading hydrolysis. This chapter provides a detailed practical procedure to perform AFEX, design the reactor, determine the mass balances, and conduct the process safely.

  18. The effect of amixin and agmatine on cytochrome c release from isolated mitochondria

    Directory of Open Access Journals (Sweden)

    K. R. Uspenska

    2017-02-01

    Full Text Available Mitochondrial nicotinic acetylcholine receptors (nAChRs control permeability transition pore formation and cytochrome c release in the presence of apoptogenic factors. This study demonstrates that pharmacological agents amixin and agmatine affect mitochondrial nAChR functioning: they slightly suppress cytochrome c release from mouse brain and liver mitochondria stimulated with apoptogenic dose of Са2+ and prevent the effect of α7 nAChR agonist PNU282987. We conclude that mitochondria may be one of therapeutic targets of amixin and agmatine.

  19. Prostatic relaxation induced by agmatine is decreased in spontaneously hypertensive rats.

    Science.gov (United States)

    Lee, Liang-Ming; Tsai, Tsung-Chin; Chung, Hsien-Hui; Tong, Yat-Ching; Cheng, Juei-Tang

    2012-09-01

    What's known on the subject? and What does the study add? Neurotransmitters are known to control prostate contractility. Agmatine is one of them and induces relaxation through imidazoline receptors. The paper shows that the action of agmatine is reduced in hypertensive rats, and that this change is related to the decrease of ATP-sensitive potassium channels in the prostate. The findings can increase our understanding of the possible underlying mechanism for the development of clinical benign prostatic hyperplasia. To compare agmatine-induced prostatic relaxation in hypertensive and control rats. To investigate the responsible mechanism(s) and the role of the ATP-sensitive potassium channel. Prostate strips were isolated from male spontaneously hypertensive (SH) rats and normal Wistar-Kyoto (WKY) rats for measurement of isometric tension. The strips were precontracted with 1 µmol/L phenylephrine or 50 mmol/L KCl. Dose-dependent relaxation of the prostatic strips was studied by cumulative administration of agmatine, 1 to 100 µmol/L, into the organ bath. Effects of specific antagonists on agmatine-induced relaxation were studied. Western blotting analysis was used to measure the gene expression of the ATP-sensitive potassium channel in the rat prostate. Prostatic relaxation induced by agmatine was markedly reduced in SH rats compared with WKY rats. The relaxation caused by agmatine was abolished by BU224, a selective imidazoline I(2)-receptor antagonist, but was not modified by efaroxan at a dose sufficient to block imidazoline I(1)-receptors. The relaxation induced by diazoxide at a concentration sufficient to activate ATP-sensitive potassium channels was markedly reduced in the SH rat prostate. Expressions of ATP-sensitive potassium channel sulphonylurea receptor and inwardly rectifying potassium channel (Kir) 6.2 subunits were both decreased in the prostate of SH rats. The decrease of agmatine-induced prostatic relaxation in SH rats is related to the change in

  20. Dioscorin pre-treatment protects A549 human airway epithelial cells from hydrogen peroxide-induced oxidative stress.

    Science.gov (United States)

    Hsu, Jeng-Yuan; Chu, Jao-Jia; Chou, Ming-Chih; Chen, Ya-Wen

    2013-10-01

    Hydrogen peroxide (H(2)O(2)) is a highly reactive oxygen species involved in lung and bronchial epithelium injury. Increased H(2)O(2) levels have been reported in expired breath condensates of patients with inflammatory airway diseases such as chronic obstructive pulmonary disease. Protecting airway epithelial cells from oxidative stress is an important task in the prevention and management of airway diseases. Previous studies demonstrate that yam (Dioscorea batatas Decne) has antioxidant and anti-trypsin activities. This study evaluated the validity of dioscorin in vitro. The results showed that dioscorin attenuated the alteration of H(2)O(2) on G2/M cell cycle arrest. This might be associated with the activation of IκB and subsequent inactivation of NF-κB. Furthermore, dioscorin suppressed IL-8 secretion and reduced changes of adhesion molecule expressions in H(2)O(2)-injured A549 cells. These results help in understanding the potential of traditional Chinese herbal medicine as treatment for airway inflammatory diseases.

  1. Effect of Agmatine Sulfate on Modulation of Matrix Metalloproteinases via PI3K/Akt-1 in HT1080 Cells.

    Science.gov (United States)

    Kim, Hyejeong; Kim, Moon-Moo

    2017-11-01

    The purpose of this study was to investigate the mechanism by which agmatine sulfate induces an anti-metastatic effect in human HT1080 fibrosarcoma cells, by affecting matrix metalloproteinases (MMPs). For the experiments, we used a non-toxic concentration of agmatine, below 512 μM, that was determined using an MTT assay. The effect of agmatine sulfate on metastasis was gelatin zymography, western blot, immunofluorescence staining and cell invasion assay. Agmatine sulfate inhibited MMP-2 activity stimulated by phenazine methosulfate (PMS). Furthermore, the expression level of MMP-2 stimulated by PMS, was decreased, but the expression level of TIMP-1 was increased in the presence of agmatine sulfate. Moreover, it was observed that the expression levels of ERK and p38 were increased, but those of PI3K and Akt-1 associated with the modulation of MMP-2 were decreased in this study. Furthermore, agmatine sulfate decreased the invasion level of human fibrosarcoma cells stimulated by VEGF. These results suggest that agmatine sulfate could inhibit metastasis through inhibition of MMP-2 via the PI3K/Akt-1 signaling pathway. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

  2. [Protective effect of pretreatment of Salvia miltiorrhiza Bunge. f. alba plasma against oxygen-glucose deprivation-induced injury of cultured rat hippocampal neurons by inhibiting apoptosis].

    Science.gov (United States)

    Li, Mei-Yi; Zhang, Yan-Bo; Zuo, Huan; Liu, Li-Li; Niu, Jing-Zhong

    2012-02-25

    The present study was to investigate the effect of Salvia miltiorrhiza Bunge. f. alba (SMA) pharmacological pretreatment on apoptosis of cultured hippocampal neurons from neonate rats under oxygen-glucose deprivation (OGD). Cultured hippocampal neurons were randomly divided into five groups (n = 6): normal plasma group, low dose SMA plasma (2.5%) group, middle dose SMA plasma (5%) group, high dose SMA plasma (10%) group and control group. The hippocampal neurons were cultured and treated with plasma from adult Wistar rats intragastrically administered with saline or aqueous extract of SMA. The apoptosis of neurons was induced by glucose-free Earle's solution containing 1 mmol/L Na2S2O4 and labeled by MTT and Annexin V/PI double staining. Moreover, protein expressions of Bcl-2 and Bax were detected by immunofluorescence. The results showed that few apoptotic cells were observed in control group, whereas the number of apoptotic cells was greatly increased in normal plasma group and low dose SMA plasma group. Both middle and high dose SMA plasma could protect cultured hippocampal neurons from apoptosis induced by OGD (P control, normal plasma and low dose SMA plasma groups, middle and high dose SMA plasma groups both showed significantly higher levels of Bcl-2 (P neurons by up-regulating the expression of Bcl-2 and down-regulating the expression of Bax.

  3. Effect of agmatine on experimental vascular endothelial dysfunction.

    Science.gov (United States)

    Nader, M A; Gamiel, N M; El-Kashef, H; Zaghloul, M S

    2016-05-01

    This study was designed to investigate the effect of agmatine sulfate (AG, CAS2482-00-0) in nicotine (NIC)-induced vascular endothelial dysfunction (VED) in rabbits. NIC was administered to produce VED in rabbits with or without AG for 6 weeks. Serum lipid profile, serum thiobarbituric acid reactive substances, reduced glutathione, superoxide dismutase generation, serum nitrite/nitrate, serum vascular cellular adhesion molecule-1 (VCAM-1), and aortic nuclear factor κB (NF-κB) levels were analyzed.Treatment with AG markedly improves lipid profile and prevented NIC-induced VED and oxidative stress. The mechanism of AG in improving NIC-induced VED may be due to the significant reduction in serum VCAM-1 levels and aortic NF-κB. Thus, it may be concluded that AG reduces the oxidative stress, nitric oxide production, VCAM-1 levels, and aortic NF-κB expression, thereby consequently improving the integrity of vascular endothelium. © The Author(s) 2015.

  4. Involvement of α₂-adrenoceptors, imidazoline, and endothelin-A receptors in the effect of agmatine on morphine and oxycodone-induced hypothermia in mice.

    Science.gov (United States)

    Bhalla, Shaifali; Andurkar, Shridhar V; Gulati, Anil

    2013-10-01

    Potentiation of opioid analgesia by endothelin-A (ET(A)) receptor antagonist, BMS182874, and imidazoline receptor/α₂-adrenoceptor agonists such as clonidine and agmatine are well known. It is also known that agmatine blocks morphine hyperthermia in rats. However, the effect of agmatine on morphine or oxycodone hypothermia in mice is unknown. The present study was carried out to study the role of α₂-adrenoceptors, imidazoline, and ET(A) receptors in morphine and oxycodone hypothermia in mice. Body temperature was determined over 6 h in male Swiss Webster mice treated with morphine, oxycodone, agmatine, and combination of agmatine with morphine or oxycodone. Yohimbine, idazoxan, and BMS182874 were used to determine involvement of α₂-adrenoceptors, imidazoline, and ET(A) receptors, respectively. Morphine and oxycodone produced significant hypothermia that was not affected by α₂-adrenoceptor antagonist yohimbine, imidazoline receptor/α₂ adrenoceptor antagonist idazoxan, or ET(A) receptor antagonist, BMS182874. Agmatine did not produce hypothermia; however, it blocked oxycodone but not morphine-induced hypothermia. Agmatine-induced blockade of oxycodone hypothermia was inhibited by idazoxan and yohimbine. The blockade by idazoxan was more pronounced compared with yohimbine. Combined administration of BMS182874 and agmatine did not produce changes in body temperature in mice. However, when BMS182874 was administered along with agmatine and oxycodone, it blocked agmatine-induced reversal of oxycodone hypothermia. This is the first report demonstrating that agmatine does not affect morphine hypothermia in mice, but reverses oxycodone hypothermia. Imidazoline receptors and α₂-adrenoceptors are involved in agmatine-induced reversal of oxycodone hypothermia. Our findings also suggest that ET(A) receptors may be involved in blockade of oxycodone hypothermia by agmatine. © 2012 The Authors Fundamental and Clinical Pharmacology © 2012 Société Française de

  5. Dual interaction of agmatine with the rat α2D-adrenoceptor: competitive antagonism and allosteric activation

    Science.gov (United States)

    Molderings, G J; Menzel, S; Kathmann, M; Schlicker, E; Göthert, M

    2000-01-01

    In segments of rat vena cava preincubated with [3H]-noradrenaline and superfused with physiological salt solution, the influence of agmatine on the electrically evoked [3H]-noradrenaline release, the EP3 prostaglandin receptor-mediated and the α2D-adrenoceptor-mediated inhibition of evoked [3H]-noradrenaline release was investigated. Agmatine (0.1–10 μM) by itself was without effect on evoked [3H]-noradrenaline release. In the presence of 10 μM agmatine, the prostaglandin E2(PGE2)-induced EP3-receptor-mediated inhibition of [3H]-noradrenaline release was not modified, whereas the α2D-adrenoceptor-mediated inhibition of [3H]-noradrenaline release induced by noradrenaline, moxonidine or clonidine was more pronounced than in the absence of agmatine. However, 1 mM agmatine antagonized the moxonidine-induced inhibition of [3H]-noradrenaline release. Agmatine concentration-dependently inhibited the binding of [3H]-clonidine and [3H]-rauwolscine to rat brain cortex membranes (Ki values 6 μM and 12 μM, respectively). In addition, 30 and 100 μM agmatine increased the rate of association and decreased the rate of dissociation of [3H]-clonidine resulting in an increased affinity of the radioligand for the α2D-adrenoceptors. [14C]-agmatine labelled specific binding sites on rat brain cortex membranes. In competition experiments. [14C]-agmatine was inhibited from binding to its specific recognition sites by unlabelled agmatine, but not by rauwolscine and moxonidine. In conclusion, the present data indicate that agmatine both acts as an antagonist at the ligand recognition site of the α2D-adrenoceptor and enhances the effects of α2-adrenoceptor agonists probably by binding to an allosteric binding site of the α2D-adrenoceptor which seems to be labelled by [14C]-agmatine. PMID:10928978

  6. Agmatine rescues autistic behaviors in the valproic acid-induced animal model of autism.

    Science.gov (United States)

    Kim, Ji-Woon; Seung, Hana; Kim, Ki Chan; Gonzales, Edson Luck T; Oh, Hyun Ah; Yang, Sung Min; Ko, Mee Jung; Han, Seol-Heui; Banerjee, Sourav; Shin, Chan Young

    2017-02-01

    Autism spectrum disorder (ASD) is an immensely challenging developmental disorder characterized primarily by two core behavioral symptoms of social communication deficits and restricted/repetitive behaviors. Investigating the etiological process and identifying an appropriate therapeutic target remain as formidable challenges to overcome ASD due to numerous risk factors and complex symptoms associated with the disorder. Among the various mechanisms that contribute to ASD, the maintenance of excitation and inhibition balance emerged as a key factor to regulate proper functioning of neuronal circuitry. Interestingly, our previous study involving the valproic acid animal model of autism (VPA animal model) has demonstrated excitatory-inhibitory imbalance (E/I imbalance) due to enhanced differentiation of glutamatergic neurons and reduced GABAergic neurons. Here, we investigated the potential of agmatine, an endogenous NMDA receptor antagonist, as a novel therapeutic candidate in ameliorating ASD symptoms by modulating E/I imbalance using the VPA animal model. We observed that a single treatment of agmatine rescued the impaired social behaviors as well as hyperactive and repetitive behaviors in the VPA animal model. We also observed that agmatine treatment rescued the overly activated ERK1/2 signaling in the prefrontal cortex and hippocampus of VPA animal models, possibly, by modulating over-excitability due to enhanced excitatory neural circuit. Taken together, our results have provided experimental evidence suggesting a possible therapeutic role of agmatine in ameliorating ASD-like symptoms in the VPA animal model of ASD. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Agmatine attenuates neuropathic pain in sciatic nerve ligated rats: modulation by hippocampal sigma receptors.

    Science.gov (United States)

    Kotagale, Nandkishor Ramdas; Shirbhate, Saurabh Haridas; Shukla, Pradeep; Ugale, Rajesh Ramesh

    2013-08-15

    Present study investigated the influence of the sigma (σ₁ and σ₂) receptors within hippocampus on the agmatine induced antinociception in neuropathic rats. Animals were subjected to sciatic nerve ligation for induction of neuropathic pain and observed the paw withdrawal latency in response to thermal hyperalgesia, cold allodynia and the mechanical hyperalgesia. Intrahippocampal (i.h.) as well as intraperitoneal (i.p.) administration of agmatine attenuated neuropathic pain in sciatic nerve ligated rats. Intrahippocampal administration of σ₁ agonist (+)-pentazocine or σ₂ agonist PB28 sensitized whereas, σ₁ antagonist BD1063 or σ₂ antagonist SM21 potentiated antinociceptive effect of agmatine. The behavioral effects correlated with hippocampal tumor necrosis factor-α (TNF-α) levels observed by western blot analysis. These results suggest that both the σ₁ and σ₂ receptor subunits within hippocampus play an important role in antinociceptive action of agmatine against neuropathic pain. © 2013 Elsevier B.V. All rights reserved.

  8. The Relationship among Tyrosine Decarboxylase and Agmatine Deiminase Pathways in Enterococcus faecalis

    Directory of Open Access Journals (Sweden)

    Marta Perez

    2017-11-01

    Full Text Available Enterococci are considered mainly responsible for the undesirable accumulation of the biogenic amines tyramine and putrescine in cheeses. The biosynthesis of tyramine and putrescine has been described as a species trait in Enterococcus faecalis. Tyramine is formed by the decarboxylation of the amino acid tyrosine, by the tyrosine decarboxylase (TDC route encoded in the tdc cluster. Putrescine is formed from agmatine by the agmatine deiminase (AGDI pathway encoded in the agdi cluster. These biosynthesis routes have been independently studied, tyrosine and agmatine transcriptionally regulate the tdc and agdi clusters. The objective of the present work is to study the possible co-regulation among TDC and AGDI pathways in E. faecalis. In the presence of agmatine, a positive correlation between putrescine biosynthesis and the tyrosine concentration was found. Transcriptome studies showed that tyrosine induces the transcription of putrescine biosynthesis genes and up-regulates pathways involved in cell growth. The tyrosine modulation over AGDI route was not observed in the mutant Δtdc strain. Fluorescence analyses using gfp as reporter protein revealed PaguB (the promoter of agdi catabolic genes was induced by tyrosine in the wild-type but not in the mutant strain, confirming that tdc cluster was involved in the tyrosine induction of putrescine biosynthesis. This study also suggests that AguR (the transcriptional regulator of agdi was implicated in interaction among the two clusters.

  9. Poly(Amido Amine)s containing agmatine and butanol side chains as efficient gene carriers

    NARCIS (Netherlands)

    Won, Young-Wook; Ankone, Martinus J.K.; Engbersen, Johannes F.J.; Feijen, Jan; Kim, S.W.

    2016-01-01

    A new type of bioreducible poly(amido amine) copolymer is synthesized by the Michael addition polymerization of cystamine bisacrylamide (CBA) with 4-aminobutylguanidine (agmatine, AGM) and 4-aminobutanol (ABOL). Since the positively charged guanidinium groups of AGM and the hydroxybutyl groups of

  10. Pretreatment of MQA, a caffeoylquinic acid derivative compound, protects against H2O2-induced oxidative stress in SH-SY5Y cells.

    Science.gov (United States)

    Tian, Xing; Gao, Lingyue; An, Li; Jiang, Xiaowen; Bai, Junpeng; Huang, Jian; Meng, Weihong; Zhao, Qingchun

    2016-12-01

    Compound MQA (1,5-O-dicaffeoyl-3-O-[4-malic acid methyl ester]-quinic acid) is a natural caffeoylquinic acid derivative isolated from Arctium lappa L. roots. This study aims to explore the neuroprotective effects of MQA against hydrogen peroxide (H 2 O 2 )-induced oxidative stress in SH-SY5Y neuroblastoma cells. The SH-SY5Y cells were divided into four groups, including control, 20 μM MQA, 200 μM H2O2, 200 μM H2O2 + 20 μM MQA groups. The effects of MQA on H 2 O 2 -induced cell death were measured by MTT and LDH assays. Hoechst 33342 and Annexin V-PI double staining were used to observed H2O2-induced apoptosis. Also, the effects of MQA on antioxidant system and mitochondrial pathway were explored. Further, steady-state phosphorylation levels of ERK1/2, Akt and GSK-3β were examined by Western blot analysis. Pretreatment with MQA prevented cell death in SH-SY5Y cells exposed to 200 μM H2O2 for 3 h. Meanwhile, Hoechst 33342 and Annexin V-PI double staining showed that MQA attenuated H 2 O 2 -induced apoptosis. These changes are related to elevation in SOD activity, reduction in MDA production and ROS formation, and increases in mitochondrial membrane potential (MMP). In addition, the potential mechanisms of MQA against H 2 O 2 -induced apoptosis are associated with increases in the Bcl-2/Bax ratio, decreases in cytochrome c release, caspase-3 and caspase-9 expressions, phosphorylation of ERK1/2, and dephosphorylation of AKT and GSK-3β. These findings suggest that protective effects of MQA against H 2 O 2 -induced apoptosis might be associated with mitochondrial apoptosis, ERK1/2 and AKT/GSK-3β pathway.

  11. Agmatine abolishes restraint stress-induced depressive-like behavior and hippocampal antioxidant imbalance in mice.

    Science.gov (United States)

    Freitas, Andiara E; Bettio, Luis E B; Neis, Vivian B; Santos, Danúbia B; Ribeiro, Camille M; Rosa, Priscila B; Farina, Marcelo; Rodrigues, Ana Lúcia S

    2014-04-03

    Agmatine has been recently emerged as a novel candidate to assist the conventional pharmacotherapy of depression. The acute restraint stress (ARS) is an unavoidable stress situation that may cause depressive-like behavior in rodents. In this study, we investigated the potential antidepressant-like effect of agmatine (10mg/kg, administered acutely by oral route) in the forced swimming test (FST) in non-stressed mice, as well as its ability to abolish the depressive-like behavior and hippocampal antioxidant imbalance induced by ARS. Agmatine reduced the immobility time in the mouse FST (1-100mg/kg) in non-stressed mice. ARS caused an increase in the immobility time in the FST, indicative of a depressive-like behavior, as well as hippocampal lipid peroxidation, and an increase in the activity of hippocampal superoxide dismutase (SOD), glutathione peroxidase (GPx) and glutathione reductase (GR) activities, reduced catalase (CAT) activity and increased SOD/CAT ratio, an index of pro-oxidative conditions. Agmatine was effective to abolish the depressive-like behavior induced by ARS and to prevent the ARS-induced lipid peroxidation and changes in SOD, GR and CAT activities and in SOD/CAT activity ratio. Hippocampal levels of reduced glutathione (GSH) were not altered by any experimental condition. In conclusion, the present study shows that agmatine was able to abrogate the ARS-induced depressive-like behavior and the associated redox hippocampal imbalance observed in stressed restraint mice, suggesting that its antidepressant-like effect may be dependent on its ability to maintain the pro-/anti-oxidative homeostasis in the hippocampus. Copyright © 2013 Elsevier Inc. All rights reserved.

  12. The molecular and metabolic influence of long term agmatine consumption.

    Science.gov (United States)

    Nissim, Itzhak; Horyn, Oksana; Daikhin, Yevgeny; Chen, Pan; Li, Changhong; Wehrli, Suzanne L; Nissim, Ilana; Yudkoff, Marc

    2014-04-04

    Agmatine (AGM), a product of arginine decarboxylation, influences multiple physiologic and metabolic functions. However, the mechanism(s) of action, the impact on whole body gene expression and metabolic pathways, and the potential benefits and risks of long term AGM consumption are still a mystery. Here, we scrutinized the impact of AGM on whole body metabolic profiling and gene expression and assessed a plausible mechanism(s) of AGM action. Studies were performed in rats fed a high fat diet or standard chow. AGM was added to drinking water for 4 or 8 weeks. We used (13)C or (15)N tracers to assess metabolic reactions and fluxes and real time quantitative PCR to determine gene expression. The results demonstrate that AGM elevated the synthesis and tissue level of cAMP. Subsequently, AGM had a widespread impact on gene expression and metabolic profiling including (a) activation of peroxisomal proliferator-activated receptor-α and its coactivator, PGC1α, and (b) increased expression of peroxisomal proliferator-activated receptor-γ and genes regulating thermogenesis, gluconeogenesis, and carnitine biosynthesis and transport. The changes in gene expression were coupled with improved tissue and systemic levels of carnitine and short chain acylcarnitine, increased β-oxidation but diminished incomplete fatty acid oxidation, decreased fat but increased protein mass, and increased hepatic ureagenesis and gluconeogenesis but decreased glycolysis. These metabolic changes were coupled with reduced weight gain and a curtailment of the hormonal and metabolic derangements associated with high fat diet-induced obesity. The findings suggest that AGM elevated the synthesis and levels of cAMP, thereby mimicking the effects of caloric restriction with respect to metabolic reprogramming.

  13. The Molecular and Metabolic Influence of Long Term Agmatine Consumption*

    Science.gov (United States)

    Nissim, Itzhak; Horyn, Oksana; Daikhin, Yevgeny; Chen, Pan; Li, Changhong; Wehrli, Suzanne L.; Nissim, Ilana; Yudkoff, Marc

    2014-01-01

    Agmatine (AGM), a product of arginine decarboxylation, influences multiple physiologic and metabolic functions. However, the mechanism(s) of action, the impact on whole body gene expression and metabolic pathways, and the potential benefits and risks of long term AGM consumption are still a mystery. Here, we scrutinized the impact of AGM on whole body metabolic profiling and gene expression and assessed a plausible mechanism(s) of AGM action. Studies were performed in rats fed a high fat diet or standard chow. AGM was added to drinking water for 4 or 8 weeks. We used 13C or 15N tracers to assess metabolic reactions and fluxes and real time quantitative PCR to determine gene expression. The results demonstrate that AGM elevated the synthesis and tissue level of cAMP. Subsequently, AGM had a widespread impact on gene expression and metabolic profiling including (a) activation of peroxisomal proliferator-activated receptor-α and its coactivator, PGC1α, and (b) increased expression of peroxisomal proliferator-activated receptor-γ and genes regulating thermogenesis, gluconeogenesis, and carnitine biosynthesis and transport. The changes in gene expression were coupled with improved tissue and systemic levels of carnitine and short chain acylcarnitine, increased β-oxidation but diminished incomplete fatty acid oxidation, decreased fat but increased protein mass, and increased hepatic ureagenesis and gluconeogenesis but decreased glycolysis. These metabolic changes were coupled with reduced weight gain and a curtailment of the hormonal and metabolic derangements associated with high fat diet-induced obesity. The findings suggest that AGM elevated the synthesis and levels of cAMP, thereby mimicking the effects of caloric restriction with respect to metabolic reprogramming. PMID:24523404

  14. Control of utilization of L-arginine, L-ornithine, agmatine, and putrescine as nitrogen sources in Escherichia coli K-12.

    OpenAIRE

    Shaibe, E; Metzer, E; Halpern, Y S

    1985-01-01

    The regulation of the synthesis of the enzymes involved in the utilization of L-arginine, L-ornithine, agmatine, and putrescine as a sole nitrogen source in Escherichia coli K-12 was examined. The synthesis of agmatine ureohydrolase, putrescine aminotransferase, and pyrroline dehydrogenase is dually controlled by catabolite repression and nitrogen availability. Catabolite repression of agmatine ureohydrolase, but not that of putrescine aminotransferase or pyrroline dehydrogenase, is relieved ...

  15. Interactions of nitric oxide with α2‐adrenoceptors within the locus coeruleus underlie the facilitation of inhibitory avoidance memory by agmatine

    Science.gov (United States)

    Shelkar, Gajanan P; Gakare, Sukanya G; Chakraborty, Suwarna; Dravid, Shashank M

    2016-01-01

    Background and Purpose Agmatine, a putative neurotransmitter, plays a vital role in learning and memory. Although it is considered an endogenous ligand of imidazoline receptors, agmatine exhibits high affinity for α‐adrenoceptors, NOS and NMDA receptors. These substrates within the locus coeruleus (LC) are critically involved in learning and memory processes. Experimental Approach The hippocampus and LC of male Wistar rat were stereotaxically cannulated for injection. Effects of agmatine, given i.p. or intra‐LC, on acquisition, consolidation and retrieval of inhibitory avoidance (IA) memory were measured. The NO donor S‐nitrosoglutathione, non‐specific (L‐NAME) and specific NOS inhibitors (L‐NIL, 7‐NI, L‐NIO), the α2‐adrenoceptor antagonist (yohimbine) or the corresponding agonist (clonidine) were injected intra‐LC before agmatine. Intra‐hippocampal injections of the NMDA antagonist, MK‐801 (dizocilpine), were used to modify the memory enhancing effects of agmatine, SNG and yohimbine. Expression of tyrosine hydroxylase (TH) and eNOS in the LC was assessed immunohistochemically. Key Results Agmatine (intra‐LC or i.p.) facilitated memory retrieval in the IA test. S‐nitrosoglutathione potentiated, while L‐NAME and L‐NIO decreased, these effects of agmatine. L‐NIL and 7‐NI did not alter the effects of agmatine. Yohimbine potentiated, whereas clonidine attenuated, effects of agmatine within the LC. The effects of agmatine, S‐nitrosoglutathione and yohimbine were blocked by intra‐hippocampal MK‐801. Agmatine increased the population of TH‐ and eNOS‐immunoreactive elements in the LC. Conclusions and Implications The facilitation of memory retrieval in the IA test by agmatine is probably mediated by interactions between eNOS, NO and noradrenergic pathways in the LC. PMID:27273730

  16. Interactions of nitric oxide with α2 -adrenoceptors within the locus coeruleus underlie the facilitation of inhibitory avoidance memory by agmatine.

    Science.gov (United States)

    Shelkar, Gajanan P; Gakare, Sukanya G; Chakraborty, Suwarna; Dravid, Shashank M; Ugale, Rajesh R

    2016-09-01

    Agmatine, a putative neurotransmitter, plays a vital role in learning and memory. Although it is considered an endogenous ligand of imidazoline receptors, agmatine exhibits high affinity for α-adrenoceptors, NOS and NMDA receptors. These substrates within the locus coeruleus (LC) are critically involved in learning and memory processes. The hippocampus and LC of male Wistar rat were stereotaxically cannulated for injection. Effects of agmatine, given i.p. or intra-LC, on acquisition, consolidation and retrieval of inhibitory avoidance (IA) memory were measured. The NO donor S-nitrosoglutathione, non-specific (L-NAME) and specific NOS inhibitors (L-NIL, 7-NI, L-NIO), the α2 -adrenoceptor antagonist (yohimbine) or the corresponding agonist (clonidine) were injected intra-LC before agmatine. Intra-hippocampal injections of the NMDA antagonist, MK-801 (dizocilpine), were used to modify the memory enhancing effects of agmatine, SNG and yohimbine. Expression of tyrosine hydroxylase (TH) and eNOS in the LC was assessed immunohistochemically. Agmatine (intra-LC or i.p.) facilitated memory retrieval in the IA test. S-nitrosoglutathione potentiated, while L-NAME and L-NIO decreased, these effects of agmatine. L-NIL and 7-NI did not alter the effects of agmatine. Yohimbine potentiated, whereas clonidine attenuated, effects of agmatine within the LC. The effects of agmatine, S-nitrosoglutathione and yohimbine were blocked by intra-hippocampal MK-801. Agmatine increased the population of TH- and eNOS-immunoreactive elements in the LC. The facilitation of memory retrieval in the IA test by agmatine is probably mediated by interactions between eNOS, NO and noradrenergic pathways in the LC. © 2016 The British Pharmacological Society.

  17. Agmatine Production by Aspergillus oryzae is Elevated by Low pH During Solid-State Cultivation.

    Science.gov (United States)

    Akasaka, Naoki; Kato, Saori; Kato, Saya; Hidese, Ryota; Wagu, Yutaka; Sakoda, Hisao; Fujiwara, Shinsuke

    2018-05-25

    Sake (rice wine) produced by multiple parallel fermentation (MPF) involving Aspergillus oryzae (strain RW) and Saccharomyces cerevisiae under solid-state cultivation conditions contained 3.5 mM agmatine, while that produced from enzymatically saccharified rice syrup by S. cerevisiae contained oryzae under solid-state cultivation (3.1 mM) but not under submerged cultivation, demonstrating that A. oryzae in solid-state culture produces agmatine. The effect of cultivation conditions on agmatine production was examined. Agmatine production was boosted at 30°C and reached the highest level (6.3 mM) at pH 5.3. The addition of l-lactic, succinic, and citric acids reduced the initial culture pH to 3.0, 3.5, and 3.2, respectively, resulting in further increase in agmatine accumulation (8.2, 8.7, and 8.3 mM, respectively). Homogenate from a solid-state culture exhibited a maximum l-arginine decarboxylase (ADC) activity (74 pmol min -1 μg -1 ) at pH 3.0 at 30°C; that from a submerged culture exhibited an extremely low activity (oryzae , even though A. oryzae lacks ADC orthologs and, instead, possesses four ornithine decarboxylases (ODC1-4). Recombinant ODC1 and ODC2 exhibited no ADC activity at acidic pH (pH 4.0>), suggesting that other decarboxylases or an unidentified ADC is involved in agmatine production. IMPORTANCE It has been speculated that, in general, fungi do not synthesize agmatine from l-arginine because they do not possess genes encoding for arginine decarboxylase. Numerous preclinical studies have shown that agmatine exerts pleiotropic effects on various molecular targets, leading to an improved quality of life. In the present study, we first demonstrated that l-arginine was a feasible substrate for agmatine production by the fungus Aspergillus oryzae RW. We observed that the productivity of agmatine by A. oryzae RW was elevated at low pH only during solid-state cultivation. A. oryzae is utilized in the production of various oriental fermented foods. The

  18. Acute agmatine administration, similar to ketamine, reverses depressive-like behavior induced by chronic unpredictable stress in mice.

    Science.gov (United States)

    Neis, Vivian B; Bettio, Luis E B; Moretti, Morgana; Rosa, Priscila B; Ribeiro, Camille M; Freitas, Andiara E; Gonçalves, Filipe M; Leal, Rodrigo B; Rodrigues, Ana Lúcia S

    Agmatine is an endogenous neuromodulator that has been shown to have antidepressant-like properties. We have previously demonstrated that it can induce a rapid increase in BDNF levels after acute administration, suggesting that agmatine may be a fast-acting antidepressant. To investigate this hypothesis, the present study evaluated the effects of a single administration of agmatine in mice subjected to chronic unpredictable stress (CUS), a model of depression responsive only to chronic treatment with conventional antidepressants. The ability of agmatine to reverse CUS-induced behavioral and biochemical alterations was evaluated and compared with those elicited by the fast-acting antidepressant (ketamine) and the conventional antidepressant (fluoxetine). After exposed to CUS for 14days, mice received a single oral dose of agmatine (0.1mg/kg), ketamine (1mg/kg) or fluoxetine (10mg/kg), and were submitted to behavioral evaluation after 24h. The exposure to CUS caused an increased immobility time in the tail suspension test (TST) but did not change anhedonic-related parameters in the splash test. Our findings provided evidence that, similarly to ketamine, agmatine is able to reverse CUS-induced depressive-like behavior in the TST. Western blot analyses of prefrontal cortex (PFC) demonstrated that mice exposed to CUS and/or treated with agmatine, fluoxetine or ketamine did not present alterations in the immunocontent of synaptic proteins [i.e. GluA1, postsynaptic density protein 95 (PSD-95) and synapsin]. Altogether, our findings indicate that a single administration of agmatine is able to reverse behavioral alterations induced by CUS in the TST, suggesting that this compound may have fast-acting antidepressant-like properties. However, there was no alteration in the levels of synaptic proteins in the PFC, a result that need to be further investigated in other time points. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Potentiation of oxycodone antinociception in mice by agmatine and BMS182874 via an imidazoline I2 receptor-mediated mechanism.

    Science.gov (United States)

    Bhalla, Shaifali; Ali, Izna; Lee, Hyaera; Andurkar, Shridhar V; Gulati, Anil

    2013-01-01

    The potentiation of oxycodone antinociception by BMS182874 (endothelin-A (ET(A)) receptor antagonist) and agmatine (imidazoline receptor/α(2)-adrenoceptor agonist) is well-documented. It is also known that imidazoline receptors but not α(2)-adrenoceptors are involved in potentiation of oxycodone antinociception by agmatine and BMS182874 in mice. However, the involvement of specific imidazoline receptor subtypes (I(1), I(2), or both) in this interaction is not clearly understood. The present study was conducted to determine the involvement of imidazoline I(1) and I(2) receptors in agmatine- and BMS182874-induced potentiation of oxycodone antinociception in mice. Antinociceptive (tail flick and hot-plate) latencies were determined in male Swiss Webster mice treated with oxycodone, agmatine, BMS182874, and combined administration of oxycodone with agmatine or BMS182874. Efaroxan (imidazoline I(1) receptor antagonist) and BU224 (imidazoline I(2) receptor antagonist) were used to determine the involvement of I(1) and I(2) imidazoline receptors, respectively. Oxycodone produced significant antinociceptive response in mice which was not affected by efaroxan but was blocked by BU224. Agmatine-induced potentiation of oxycodone antinociception was blocked by BU224 but not by efaroxan. Similarly, BMS182874-induced potentiation of oxycodone antinociception was blocked by BU224 but not by efaroxan. This is the first report demonstrating that BMS182874- or agmatine-induced enhancement of oxycodone antinociception is blocked by BU224 but not by efaroxan. We conclude that imidazoline I(2) receptors but not imidazoline I(1) receptors are involved in BMS182874- and agmatine-induced potentiation of oxycodone antinociception in mice. Copyright © 2012 Elsevier Inc. All rights reserved.

  20. Effect of agmatine on the development of morphine dependence in rats: potential role of cAMP system

    Science.gov (United States)

    Aricioglu, Feyza; Means, Andrea; Regunathan, Soundar

    2010-01-01

    Agmatine is an endogenous amine derived from arginine that potentiates morphine analgesia and blocks symptoms of naloxone-precipitated morphine withdrawal in rats. In this study, we sought to determine whether treatment with agmatine during the development of morphine dependence inhibits the withdrawal symptoms and that the effect is mediated by cAMP system. Exposure of rats to morphine for 7 days resulted in marked naloxone-induced withdrawal symptoms and agmatine treatment along with morphine significantly decreasing the withdrawal symptoms. The levels of cAMP were markedly increased in morphine-treated rat brain slices when incubated with naloxone and this increase was significantly reduced in rats treated with morphine and agmatine. The induction of tyrosine hydroxylase after morphine exposure was also reduced in locus coeruleus when agmatine was administered along with morphine. We conclude that agmatine reduces the development of dependence to morphine and that this effect is probably mediated by the inhibition of cAMP signaling pathway during chronic morphine exposure. PMID:15541421

  1. The effect of agmatine on trichothecene type B and zearalenone production in Fusarium graminearum, F. culmorum and F. poae

    Directory of Open Access Journals (Sweden)

    Matias Pasquali

    2016-02-01

    Full Text Available Agmatine and other putrescines are known for being strong inducers of deoxynivalenol (DON production in Fusarium graminearum. Other important species produce DON and/or other trichothecene type B toxins (3 acetylated DON, 15 acetylated DON, Fusarenon-X, Nivalenol, such as F. culmorum and F. poae. In order to verify whether the mechanism of the regulation of trichothecene type B induction by agmatine is shared by different species of Fusarium, we tested the hypothesis on 19 strains belonging to 3 Fusarium species (F. graminearum, F. culmorum, F. poae with diverse genetic chemotypes (3ADON, 15ADON, NIV by measuring trichothecene B toxins such as DON, NIV, Fusarenon-X, 3ADON and 15ADON. Moreover, we tested whether other toxins like zearalenone were also boosted by agmatine. The trichothecene type B boosting effect was observed in the majority of strains (13 out of 19 in all the three species. Representative strains from all three genetic chemotypes were able to boost toxin production after agmatine treatment. We identified the non-responding strains to the agmatine stimulus, which may contribute to deciphering the regulatory mechanisms that link toxin production to agmatine (and, more generally, polyamines.

  2. 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.

  3. 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

  4. Imidazoline binding sites mediates anticompulsive-like effect of agmatine in marble-burying behavior in mice.

    Science.gov (United States)

    Dixit, Madhura P; Thakre, Prajwal P; Pannase, Akshay S; Aglawe, Manish M; Taksande, Brijesh G; Kotagale, Nandkishor R

    2014-06-05

    Agmatine is a cationic amine formed by decarboxylation of l-arginine by the mitochondrial enzyme arginine decarboxylase and widely distributed in mammalian brain. Although the precise function of endogenous agmatine has been largely remained unclear, its exogenous administration demonstrated beneficial effects in several neurological and psychiatric disorders. This study was planned to examine the role of imidazoline binding sites in the anticompulsive-like effect of agmatine on marble-burying behavior. Agmatine (20 and 40mg/kg, ip), mixed imidazoline I1/α2 agonists clonidine (60µg/kg, ip) and moxonidine (0.25mg/kg, ip), and imidazoline I2 agonist 2- BFI (10mg/kg, ip) showed significant inhibition of marble burying behavior in mice. In combination studies, the anticompulsive-like effect of agmatine (10mg/kg, ip) was significantly potentiated by prior administration of moxonidine (0.25mg/kg, ip) or clonidine (30µg/kg,) or 2-BFI (5mg/kg, ip). Conversely, efaroxan (1mg/kg, ip), an I1 antagonist and idazoxan (0.25mg/kg, ip), an I2 antagonist completely blocked the anticompulsive-like effect of agmatine (10mg/kg, ip). These drugs at doses used here did not influence the basal locomotor activity in experimental animals. These results clearly indicated the involvement of imidazoline binding sites in anti-compulsive-like effect of agmatine. Thus, imidazoline binding sites can be explored further as novel therapeutic target for treatment of anxiety and obsessive compulsive disorders. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. Pharmacological analysis of the cardiac sympatho-inhibitory actions of moxonidine and agmatine in pithed spontaneously hypertensive rats.

    Science.gov (United States)

    Cobos-Puc, Luis E; Sánchez-López, Araceli; Centurión, David

    2016-11-15

    This study shows that in spontaneously hypertensive rats (SHR) of 14-weeks-old, the sympathetically-induced, but not noradrenaline-induced tachycardic response are higher than age-matched Wistar normotensive rats. Furthermore, in SHR the sympathetically-induced tachycardic response was: (1) unaffected by moxonidine (3μg/kgmin); (2) partially inhibited by B-HT 933 (30μg/kgmin), both at the lowest doses; and (3) completely inhibited by the highest doses of B-HT 933 (100μg/kgmin), moxonidine (10μg/kgmin) or agmatine (1000 and 3000μg/kgmin) while the noradrenaline-induced tachycardic responses remained unaffected by the above compounds, except by 3000μg/kgmin agmatine. In SHR, 300μg/kg rauwolscine failed to block the sympatho-inhibition to 100μg/kgmin B-HT 933 or 10μg/kgmin moxonidine, but 1000μg/kg rauwolscine abolished, partially antagonized, and did not modify the sympatho-inhibition to the highest doses of B-HT 933, moxonidine, and agmatine, respectively, 3000μg/kg AGN 192403 or 300μg/kg BU224 given alone had no effect in the moxonidine- or agmatine-induced sympatho-inhibition, and the combination rauwolscine plus AGN 192403 but not plus BU224, abolished the sympatho-inhibition to the highest doses of moxonidine and agmatine. In conclusion, the sympathetically-induced tachycardic responses in SHR are inhibited by moxonidine and agmatine. The inhibition of moxonidine is mainly mediated by prejunctional α 2 -adrenoceptors and to a lesser extent by I 1 -imidazoline receptors, while the inhibition of agmatine is mediated by prejunctional α 2 -adrenoceptors and I 1 -imidazoline receptors at the same extent. Notwithstanding, the inhibitory function of α 2 -adrenoceptors seems to be altered in SHR compared with Wistar normotensive rats. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Determination of the protection efficacy and homogeneity of the distribution of sunscreens applied onto skin pre-treated with cosmetic products.

    Science.gov (United States)

    Weigmann, Hans-Jürgen; de Sainte Claire, Maude Suisse; Schanzer, Sabine; Patzelt, Alexa; Meinke, Martina; Antoniou, Christina; Sterry, Wolfram; Lademann, Jürgen

    2012-05-01

    The efficacy of sunscreens depends decisively on the homogeneity of its distribution on the skin surface, which is sensitively reflected by two spectroscopic data - the factor of inhomogeneity and the sum transmission - measured after tape stripping. The aim of this study was to investigate the influence of a skin pre-treatment with body lotion on the layout of the formulations. Six healthy volunteers were pre-treated using the body lotion, Nivea Body (Beiersdorf AG, Hamburg, Germany). The sunscreen was an oil/water (o/w) emulsion, Roc SPF 8 (RoC SA, Paris, France). The tape stripped tesa films were measured with a modified UV/VIS spectrometer Lambda 5 (PerkinElmer, Frankfurt/Main, Germany), the data of which were used to calculate both measurands. The obtained results made clear that the original spectroscopic data must be corrected taking into account the changed amounts of horny layer particles removed with the individual tape strips after pre-treatment. As a consequence of the correction, the factors of inhomogeneity as well as the sum transmissions confirm a more homogeneous distribution of the applied sunscreen. The findings confirm that the applied method is well suited to obtain information on the distribution of topically applied substances, and furthermore that the influence of the pre-treatment of the skin with the body lotion enhances the homogeneity of distribution and thus the sunscreen efficacy. © 2011 John Wiley & Sons A/S.

  7. Agmatine for combined treatment of epilepsy, depression and cognitive impairment in chronic epileptic animals.

    Science.gov (United States)

    Singh, Tanveer; Bagga, Neetu; Kaur, Anureet; Kaur, Navjot; Gawande, Dinesh Yugraj; Goel, Rajesh Kumar

    2017-08-01

    Epilepsy is fourth most common neurological disorders associated with depression and cognitive deficits. As per present scenario, none of the antiseizure drugs have been reported successful to have ameliorative effect on epilepsy associated depression and cognitive deficits. Thus, the study was envisioned to assess an ameliorative potential of agmatine on epilepsy and its efficacy and safety for management of associated depression and cognitive deficits. The animals were made epileptic employing pentylenetetrazole (35mg/kg i.p. every 48±2h) kindling model of epilepsy and subsequently were treated with vehicle, valproic acid (300mg/kg/day i.p.) and agmatine (2.5, 5, and 10mg/kg)/day/i.p. for 15days. Except naïve, all the groups were challenged with same pentylenetetrazole dose as employed during kindling on days 5, 10, and 15 to evaluate seizure severity. Two hours after seizure severity test, tail suspension test and passive shock avoidance paradigm was employed to evaluate depression and cognitive behavior respectively. Results suggested that epileptic animals were significantly associated with depression and cognitive impairment. Chronic valproate treatment significantly reduced seizure severity, but was found unable to mitigate depression and cognitive deficits. However, agmatine treatment dose dependently ameliorated seizure severity as well as associated depression and cognitive deficits. On 15th day, animals were euthanized and pertinent neurochemical estimations were carried out in cortical and hippocampal areas of the mice brain. Thus, study concluded that agmatine ameliorated seizure severity, depression and cognitive impairment in epileptic animals, possibly via restoring glutamate-GABA neurotransmission and serotonin synthesis with decreased nitrosative stress. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  8. Augmenting the Genetic Toolbox for Sulfolobus islandicus with a Stringent Positive Selectable Marker for Agmatine Prototrophy

    Science.gov (United States)

    Cooper, Tara E.; Krause, David J.

    2013-01-01

    Sulfolobus species have become the model organisms for studying the unique biology of the crenarchaeal division of the archaeal domain. In particular, Sulfolobus islandicus provides a powerful opportunity to explore natural variation via experimental functional genomics. To support these efforts, we further expanded genetic tools for S. islandicus by developing a stringent positive selection for agmatine prototrophs in strains in which the argD gene, encoding arginine decarboxylase, has been deleted. Strains with deletions in argD were shown to be auxotrophic for agmatine even in nutrient-rich medium, but growth could be restored by either supplementation of exogenous agmatine or reintroduction of a functional copy of the argD gene from S. solfataricus P2 into the ΔargD host. Using this stringent selection, a robust targeted gene knockout system was established via an improved next generation of the MID (marker insertion and unmarked target gene deletion) method. Application of this novel system was validated by targeted knockout of the upsEF genes involved in UV-inducible cell aggregation formation. PMID:23835176

  9. Agmatine Reduces Lipopolysaccharide-Mediated Oxidant Response via Activating PI3K/Akt Pathway and Up-Regulating Nrf2 and HO-1 Expression in Macrophages.

    Directory of Open Access Journals (Sweden)

    Jianshen Chai

    Full Text Available Macrophages are key responders of inflammation and are closely related with oxidative stress. Activated macrophages can enhance oxygen depletion, which causes an overproduction of reactive oxygen species (ROS and leads to further excessive inflammatory response and tissue damage. Agmatine, an endogenous metabolite of L-arginine, has recently been shown to have neuroprotective effects based on its antioxidant properties. However, the antioxidant effects of agmatine in peripheral tissues and cells, especially macrophages, remain unclear. In this study we explored the role of agmatine in mediating antioxidant effects in RAW 264.7 cells and studied its antioxidant mechanism. Our data demonstrate that agmatine is an activator of Nrf2 signaling that markedly enhances Nrf2 nuclear translocation, increases nuclear Nrf2 protein level, up-regulates the expression of the Nrf2 downstream effector HO-1, and attenuates ROS generation induced by Lipopolysaccharide (LPS. We further demonstrated that the agmatine-induced activation of Nrf2 is likely through the PI3K/Akt pathway. LY294002, a specific PI3K/Akt inhibitor, abolished agmatine-induced HO-1 up-regulation and ROS suppression significantly. Inhibiting HO-1 pathway significantly attenuated the antioxidant effect of agmatine which the products of HO-1 enzymatic activity contributed to. Furthermore, the common membrane receptors of agmatine were evaluated, revealing that α2-adrenoceptor, I1-imidazoline receptor or I2-imidazoline receptor are not required by the antioxidant properties of agmatine. Taken together, our findings revealed that agmatine has antioxidant activity against LPS-induced ROS accumulation in RAW 264.7 cells involving HO-1 expression induced by Nrf2 via PI3K/Akt pathway activation.

  10. Agmatine produces antidepressant-like effects by activating AMPA receptors and mTOR signaling.

    Science.gov (United States)

    Neis, Vivian Binder; Moretti, Morgana; Bettio, Luis Eduardo B; Ribeiro, Camille M; Rosa, Priscila Batista; Gonçalves, Filipe Marques; Lopes, Mark William; Leal, Rodrigo Bainy; Rodrigues, Ana Lúcia S

    2016-06-01

    The activation of AMPA receptors and mTOR signaling has been reported as mechanisms underlying the antidepressant effects of fast-acting agents, specially the NMDA receptor antagonist ketamine. In the present study, oral administration of agmatine (0.1mg/kg), a neuromodulator that has been reported to modulate NMDA receptors, caused a significant reduction in the immobility time of mice submitted to the tail suspension test (TST), an effect prevented by the administration of DNQX (AMPA receptor antagonist, 2.5μg/site, i.c.v.), BDNF antibody (1μg/site, i.c.v.), K-252a (TrkB receptor antagonist, 1μg/site, i.c.v.), LY294002 (PI3K inhibitor, 10nmol/site, i.c.v.) or rapamycin (selective mTOR inhibitor, 0.2nmol/site, i.c.v.). Moreover, the administration of lithium chloride (non-selective GSK-3β inhibitor, 10mg/kg, p.o.) or AR-A014418 (selective GSK-3β inhibitor, 0.01μg/site, i.c.v.) in combination with a sub-effective dose of agmatine (0.0001mg/kg, p.o.) reduced the immobility time in the TST when compared with either drug alone. Furthermore, increased immunocontents of BDNF, PSD-95 and GluA1 were found in the prefrontal cortex of mice just 1h after agmatine administration. These results indicate that the antidepressant-like effect of agmatine in the TST may be dependent on the activation of AMPA and TrkB receptors, PI3K and mTOR signaling as well as inhibition of GSK-3β, and increase in synaptic proteins. The results contribute to elucidate the complex signaling pathways involved in the antidepressant effect of agmatine and reinforce the pivotal role of these molecular targets for antidepressant responses. Copyright © 2016 Elsevier B.V. and ECNP. All rights reserved.

  11. 40 CFR 406.26 - Pretreatment standards for new sources.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 28 2010-07-01 2010-07-01 true Pretreatment standards for new sources. 406.26 Section 406.26 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS GRAIN MILLS POINT SOURCE CATEGORY Corn Dry Milling Subcategory § 406.26 Pretreatment...

  12. 40 CFR 406.34 - Pretreatment standards for existing sources.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 28 2010-07-01 2010-07-01 true Pretreatment standards for existing sources. 406.34 Section 406.34 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... § 406.34 Pretreatment standards for existing sources. Any existing source subject to this subpart that...

  13. 40 CFR 406.44 - Pretreatment standards for existing sources.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 28 2010-07-01 2010-07-01 true Pretreatment standards for existing sources. 406.44 Section 406.44 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... § 406.44 Pretreatment standards for existing sources. Any existing source subject to this subpart that...

  14. 40 CFR 406.16 - Pretreatment standards for new sources.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 28 2010-07-01 2010-07-01 true Pretreatment standards for new sources. 406.16 Section 406.16 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS GRAIN MILLS POINT SOURCE CATEGORY Corn Wet Milling Subcategory § 406.16 Pretreatment...

  15. Protection of human cells against the effects of cadmium chloride by pretreatment with vitamins, interferon, and prior low-dose γ-irradiation

    International Nuclear Information System (INIS)

    Kusainova, K.A.; Vasil'eva, I.M.; Chekova, V.V.; Akhmatullina, N.B.; Zasukhina, G.D.

    1992-01-01

    Within the increasing environmental pollution there is a need to discover means to protect humans from the mutagenic effects of chemical pollutants. Natural antimutagens such as interferon and vitamins have some protective properties. Interferons simulate a variety of repair pathways in human cells and reduce the numbers of mutations induced by physical and chemical mutagens. This study compares the protective properties of interferon and vitamins with the known protective effects of small doses of ionizing radiation

  16. Long-term pretreatment with desethylamiodarone (DEA) or amiodarone (AMIO) protects against coronary artery occlusion induced ventricular arrhythmias in conscious rats.

    Science.gov (United States)

    Morvay, Nikolett; Baczkó, István; Sztojkov-Ivanov, Anita; Falkay, György; Papp, Julius Gy; Varró, András; Leprán, István

    2015-09-01

    The aim of this investigation was to compare the effectiveness of long-term pretreatment with amiodarone (AMIO) and its active metabolite desethylamiodarone (DEA) on arrhythmias induced by acute myocardial infarction in rats. Acute myocardial infarction was induced in conscious, male, Sprague-Dawley rats by pulling a previously inserted loose silk loop around the left main coronary artery. Long-term oral pretreatment with AMIO (30 or 100 mg·(kg body mass)(-1)·day(-1), loading dose 100 or 300 mg·kg(-1) for 3 days) or DEA (15 or 50 mg·kg(-1)·day(-1), loading dose 100 or 300 mg·kg(-1) for 3 days), was applied for 1 month before the coronary artery occlusion. Chronic oral treatment with DEA (50 mg·kg(-1)·day(-1)) resulted in a similar myocardial DEA concentration as chronic AMIO treatment (100 mg·kg(-1)·day(-1)) in rats (7.4 ± 0.7 μg·g(-1) and 8.9 ± 2.2 μg·g(-1)). Both pretreatments in the larger doses significantly improved the survival rate during the acute phase of experimental myocardial infarction (82% and 64% by AMIO and DEA, respectively, vs. 31% in controls). Our results demonstrate that chronic oral treatment with DEA resulted in similar cardiac tissue levels to that of chronic AMIO treatment, and offered an equivalent degree of antiarrhythmic effect against acute coronary artery ligation induced ventricular arrhythmias in conscious rats.

  17. Mutagenic and morphologic impacts of 1.8 GHz radiofrequency radiation on human peripheral blood lymphocytes (hPBLs) and possible protective role of pre-treatment with Ginkgo biloba (EGb 761)

    Energy Technology Data Exchange (ETDEWEB)

    Esmekaya, Meric Arda, E-mail: mericarda@yahoo.com [Department of Biophysics, Gazi University, Faculty of Medicine and Gazi Non-ionizing Radiation, Protection (GNRP) Center, Ankara (Turkey); Aytekin, Ebru [Department of Medical Genetics, Gazi University Faculty of Medicine, Ankara (Turkey); Ozgur, Elcin; Gueler, Goeknur [Department of Biophysics, Gazi University, Faculty of Medicine and Gazi Non-ionizing Radiation, Protection (GNRP) Center, Ankara (Turkey); Ergun, Mehmet Ali [Department of Medical Genetics, Gazi University Faculty of Medicine, Ankara (Turkey); Oemeroglu, Suna [Department of Histology and Embryology, Gazi University, Faculty of Medicine, Ankara (Turkey); Seyhan, Nesrin [Department of Biophysics, Gazi University, Faculty of Medicine and Gazi Non-ionizing Radiation, Protection (GNRP) Center, Ankara (Turkey)

    2011-12-01

    The mutagenic and morphologic effects of 1.8 GHz Global System for Mobile Communications (GSM) modulated RF (radiofrequency) radiation alone and in combination with Ginkgo biloba (EGb 761) pre-treatment in human peripheral blood lymphocytes (hPBLs) were investigated in this study using Sister Chromatid Exchange (SCE) and electron microscopy. Cell viability was assessed with 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) reduction assay. The lymphocyte cultures were exposed to GSM modulated RF radiation at 1.8 GHz for 6, 8, 24 and 48 h with and without EGb 761. We observed morphological changes in pulse-modulated RF radiated lymphocytes. Longer exposure periods led to destruction of organelle and nucleus structures. Chromatin change and the loss of mitochondrial crista occurred in cells exposed to RF for 8 h and 24 h and were more pronounced in cells exposed for 48 h. Cytoplasmic lysis and destruction of membrane integrity of cells and nuclei were also seen in 48 h RF exposed cells. There was a significant increase (p < 0.05) in SCE frequency in RF exposed lymphocytes compared to sham controls. EGb 761 pre-treatment significantly decreased SCE from RF radiation. RF radiation also inhibited cell viability in a time dependent manner. The inhibitory effects of RF radiation on the growth of lymphoctes were marked in longer exposure periods. EGb 761 pre-treatment significantly increased cell viability in RF + EGb 761 treated groups at 8 and 24 h when compared to RF exposed groups alone. The results of our study showed that RF radiation affects cell morphology, increases SCE and inhibits cell proliferation. However, EGb 761 has a protective role against RF induced mutagenity. We concluded that RF radiation induces chromosomal damage in hPBLs but this damage may be reduced by EGb 761 pre-treatment. - Highlights: Black-Right-Pointing-Pointer RF Radiation inhibits cell proliferation. Black-Right-Pointing-Pointer RF radiation induces chromosomal damage

  18. Insights into the molecular basis for substrate binding and specificity of the wild-type L-arginine/agmatine antiporter AdiC.

    Science.gov (United States)

    Ilgü, Hüseyin; Jeckelmann, Jean-Marc; Gapsys, Vytautas; Ucurum, Zöhre; de Groot, Bert L; Fotiadis, Dimitrios

    2016-09-13

    Pathogenic enterobacteria need to survive the extreme acidity of the stomach to successfully colonize the human gut. Enteric bacteria circumvent the gastric acid barrier by activating extreme acid-resistance responses, such as the arginine-dependent acid resistance system. In this response, l-arginine is decarboxylated to agmatine, thereby consuming one proton from the cytoplasm. In Escherichia coli, the l-arginine/agmatine antiporter AdiC facilitates the export of agmatine in exchange of l-arginine, thus providing substrates for further removal of protons from the cytoplasm and balancing the intracellular pH. We have solved the crystal structures of wild-type AdiC in the presence and absence of the substrate agmatine at 2.6-Å and 2.2-Å resolution, respectively. The high-resolution structures made possible the identification of crucial water molecules in the substrate-binding sites, unveiling their functional roles for agmatine release and structure stabilization, which was further corroborated by molecular dynamics simulations. Structural analysis combined with site-directed mutagenesis and the scintillation proximity radioligand binding assay improved our understanding of substrate binding and specificity of the wild-type l-arginine/agmatine antiporter AdiC. Finally, we present a potential mechanism for conformational changes of the AdiC transport cycle involved in the release of agmatine into the periplasmic space of E. coli.

  19. Agmatine attenuates chronic unpredictable mild stress-induced anxiety, depression-like behaviours and cognitive impairment by modulating nitrergic signalling pathway.

    Science.gov (United States)

    Gawali, Nitin B; Bulani, Vipin D; Gursahani, Malvika S; Deshpande, Padmini S; Kothavade, Pankaj S; Juvekar, Archana R

    2017-05-15

    Agmatine, a neurotransmitter/neuromodulator, has shown to exert numerous effects on the CNS. Chronic stress is a risk factor for development of depression, anxiety and deterioration of cognitive performance. Compelling evidences indicate an involvement of nitric oxide (NO) pathway in these disorders. Hence, investigation of the beneficial effects of agmatine on chronic unpredictable mild stress (CUMS)-induced depression, anxiety and cognitive performance with the involvement of nitrergic pathway was undertaken. Mice were subjected to a battery of stressors for 28days. Agmatine (20 and 40mg/kg, i.p.) alone and in combination with NO modulators like L-NAME (15mg/kg, i.p.) and l-arginine (400mg/kg i.p.) were administered daily. The results showed that 4-weeks CUMS produces significant depression and anxiety-like behaviour. Stressed mice have also shown a significant high serum corticosterone (CORT) and low BDNF level. Chronic treatment with agmatine produced significant antidepressant-like behaviour in forced swim test (FST) and sucrose preference test, whereas, anxiolytic-like behaviour in elevated plus maze (EPM) and open field test (OFT) with improved cognitive impairment in Morris water maze (MWM). Furthermore, agmatine administration reduced the levels of acetylcholinesterase and oxidative stress markers. In addition, agmatine treatment significantly increased the BDNF level and inhibited serum CORT level in stressed mice. Treatment with L-NAME (15mg/kg) potentiated the effect of agmatine whereas l-arginine abolished the anxiolytic, antidepressant and neuroprotective effects of agmatine. Agmatine showed marked effect on depression and anxiety-like behaviour in mice through nitrergic pathway, which may be related to modulation of oxidative-nitrergic stress, CORT and BDNF levels. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. 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.

  1. Neuroprotective effects of agmatine in experimental peripheral nerve injury in rats: a prospective randomized and placebo-controlled trial.

    Science.gov (United States)

    Sezer, Aykut; Guclu, Bulent; Kazanci, Burak; Cakir, Murteza; Coban, Mustafa Kemal

    2014-01-01

    The purpose of this study was to demonstrate the activity of agmatine, an inducible nitric oxide synthase (iNOS) inhibitor and selective N-methyl-D-aspartate receptor (NMDAR) antagonist, on reducing tissue damage in distal part of traumatic nerve in an experimental rat peripheral nerve injury model. Sciatic nerves of 30 Sprague Dawley male rats were used. Rats were divided into 5 groups; group 1 (n=6), control group; group 2 (n=6), axonotmesis + placebo group; group 3 (n=6), axonotmesis + 50 mg/kg agmatine treatment group; group 4 (n=6), neurotmesis + placebo group; group 5 (n=6), neurotmesis + 50 mg/kg agmatine treatment group. Axonolysis, axon degeneration, edema, hemorrhage, and inflammation were evaluated in histopathologic examinations of all the groups. When group 2 was compared with group 3 in histopathologic sections, axonolysis was less in group 3 (p=0.007), as was axon degeneration (p=0.022) and edema (p=0.018). When group 4 was compared with group 5, axonolysis was less in group 5 (p=0.009), as was axon degeneration (p=0.006) and edema (p=0.021). This study demonstrated agmatine to have antioxidant and antineurotoxic effects in an experimental rat peripheral nerve injury model.

  2. Identification of functional amino acid residues involved in polyamine and agmatine transport by human organic cation transporter 2.

    Science.gov (United States)

    Higashi, Kyohei; Imamura, Masataka; Fudo, Satoshi; Uemura, Takeshi; Saiki, Ryotaro; Hoshino, Tyuji; Toida, Toshihiko; Kashiwagi, Keiko; Igarashi, Kazuei

    2014-01-01

    Polyamine (putrescine, spermidine and spermine) and agmatine uptake by the human organic cation transporter 2 (hOCT2) was studied using HEK293 cells transfected with pCMV6-XL4/hOCT2. The Km values for putrescine and spermidine were 7.50 and 6.76 mM, and the Vmax values were 4.71 and 2.34 nmol/min/mg protein, respectively. Spermine uptake by hOCT2 was not observed at pH 7.4, although it inhibited both putrescine and spermidine uptake. Agmatine was also taken up by hOCT2, with Km value: 3.27 mM and a Vmax value of 3.14 nmol/min/mg protein. Amino acid residues involved in putrescine, agmatine and spermidine uptake by hOCT2 were Asp427, Glu448, Glu456, Asp475, and Glu516. In addition, Glu524 and Glu530 were involved in putrescine and spermidine uptake activity, and Glu528 and Glu540 were weakly involved in putrescine uptake activity. Furthermore, Asp551 was also involved in the recognition of spermidine. These results indicate that the recognition sites for putrescine, agmatine and spermidine on hOCT2 strongly overlap, consistent with the observation that the three amines are transported with similar affinity and velocity. A model of spermidine binding to hOCT2 was constructed based on the functional amino acid residues.

  3. Identification of functional amino acid residues involved in polyamine and agmatine transport by human organic cation transporter 2.

    Directory of Open Access Journals (Sweden)

    Kyohei Higashi

    Full Text Available Polyamine (putrescine, spermidine and spermine and agmatine uptake by the human organic cation transporter 2 (hOCT2 was studied using HEK293 cells transfected with pCMV6-XL4/hOCT2. The Km values for putrescine and spermidine were 7.50 and 6.76 mM, and the Vmax values were 4.71 and 2.34 nmol/min/mg protein, respectively. Spermine uptake by hOCT2 was not observed at pH 7.4, although it inhibited both putrescine and spermidine uptake. Agmatine was also taken up by hOCT2, with Km value: 3.27 mM and a Vmax value of 3.14 nmol/min/mg protein. Amino acid residues involved in putrescine, agmatine and spermidine uptake by hOCT2 were Asp427, Glu448, Glu456, Asp475, and Glu516. In addition, Glu524 and Glu530 were involved in putrescine and spermidine uptake activity, and Glu528 and Glu540 were weakly involved in putrescine uptake activity. Furthermore, Asp551 was also involved in the recognition of spermidine. These results indicate that the recognition sites for putrescine, agmatine and spermidine on hOCT2 strongly overlap, consistent with the observation that the three amines are transported with similar affinity and velocity. A model of spermidine binding to hOCT2 was constructed based on the functional amino acid residues.

  4. Further analysis of the inhibition by agmatine on the cardiac sympathetic outflow: Role of the α2-adrenoceptor subtypes.

    Science.gov (United States)

    Cobos-Puc, Luis; Aguayo-Morales, Hilda; Ventura-Sobrevilla, Janeth; Luque-Contreras, Diana; Chin-Chan, Miguel

    2017-06-15

    This study has investigated the role of the α 2 -adrenoceptor subtypes involved in the inhibition of the cardiac sympathetic outflow induced by intravenous (i.v) infusions of agmatine. Therefore, we analysed the effect of an i.v. bolus injections of the selective antagonists BRL 44408 (300μg/kg; α 2A ), imiloxan (3000μg/kg; α 2B ), and JP-1302 (300μg/kg; α 2C ) given separately, and their combinations: BRL 44408 plus Imiloxan, JP 1302 plus imiloxan, BRL 44408 plus JP-1302, BRL 44408 plus imiloxan plus JP-1302 on the cardiac sympatho-inhibition of agmatine. Also, the effect of the combination BRL 44408 plus JP-1302 plus AGN 192403 (3000μg/kg; I 1 antagonist) was evaluated. In this way, i.v. infusions of 1000μg/kg min of agmatine, but not 300, inhibited the tachycardic response induced by electrical stimulation. Furthermore, the antagonists used or their combinations had no effect on the electrically-induced tachycardic response. On the other hand, the inhibitory response of agmatine was: (1) partially antagonized by BRL 44408 or JP-1302 given separately, a similar response was observed when we administered their combination with imiloxan, but not by imiloxan alone, (2) antagonized in greater magnitude by the combination BRL 44408 plus JP-1302 or the combination BRL 44408 plus imiloxan plus JP-1302, and (3) abolished by the combination BRL 44408 plus JP-1302 plus AGN 192403. Taken together, these results demonstrate that the α 2A - and α 2C -adrenoceptor subtypes and I 1 -imidazoline receptors are involved in the inhibition of the cardiac sympathetic outflow induced by agmatine. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Involvement of nitric oxide in anticompulsive-like effect of agmatine on marble-burying behaviour in mice.

    Science.gov (United States)

    Gawali, Nitin B; Chowdhury, Amrita A; Kothavade, Pankaj S; Bulani, Vipin D; Nagmoti, Dnyaneshwar M; Juvekar, Archana R

    2016-01-05

    In view of the reports that nitric oxide modulates the neurotransmitters implicated in obsessive-compulsive disorder (OCD), patients with OCD exhibit higher plasma nitrate levels, and drugs useful in OCD influence nitric oxide. Agmatine is a polyamine and widely distributed in mammalian brain which interacts with nitrergic systems. Hence, the present study was carried out to understand the involvement of nitrergic systems in the anticompulsive-like effect of agmatine. We used marble-burying behaviour (MBB) of mice as the animal model of OCD, and nitric oxide levels in hippocampus (HC) and cortex homogenate were measured. Results revealed that, agmatine (20 and 40mg/kg, i.p) significantly inhibited the MBB. Intraperitoneal administration of nitric oxide enhancers viz. nitric oxide precursor - l-arginine (l-ARG) (400mg/kg and 800mg/kg) increased MBB as well as brain nitrites levels, whereas treatment with N(G)-nitro-l-arginine methyl ester (l-NAME) neuronal nitric oxide synthase inhibitor (30mg/kg and 50mg/kg, i.p.) and 7-nitroindazole (7-NI) (20mg/kg and 40mg/kg) attenuated MBB and nitrites levels in brain. Further, in combination studies, the anticompulsive-like effect of agmatine (20mg/kg, ip) was exacerbated by prior administration of l-ARG (400mg/kg) and conversely l-NAME (15mg/kg) or 7-NI (10.0mg/kg) attenuated OCD-like behaviour with HC and cortex changes in the levels of NO. None of the above treatment had any significant influence on locomotor activity. In conclusion, Agmatine is effective in ameliorating the compulsive-like behaviour in mice which appears to be related to nitric oxide in brain. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Binding mechanisms for histamine and agmatine ligands in plasmid deoxyribonucleic acid purifications.

    Science.gov (United States)

    Sousa, Ângela; Pereira, Patrícia; Sousa, Fani; Queiroz, João A

    2014-10-31

    Histamine and agmatine amino acid derivatives were immobilized into monolithic disks, in order to combine the specificity and selectivity of the ligand with the high mass transfer and binding capacity offered by monolithic supports, to purify potential plasmid DNA biopharmaceuticals. Different elution strategies were explored by changing the type and salt concentration, as well as the pH, in order to understand the retention pattern of different plasmids isoforms The pVAX1-LacZ supercoiled isoform was isolated from a mixture of pDNA isoforms by using NaCl increasing stepwise gradient and also by ammonium sulfate decreasing stepwise gradient, in both histamine and agmatine monoliths. Acidic pH in the binding buffer mainly strengthened ionic interactions with both ligands in the presence of sodium chloride. Otherwise, for histamine ligand, pH values higher than 7 intensified hydrophobic interactions in the presence of ammonium sulfate. In addition, circular dichroism spectroscopy studies revealed that the binding and elution chromatographic conditions, such as the combination of high ionic strength with extreme pH values can reversibly influence the structural stability of the target nucleic acid. Therefore, ascending sodium chloride gradients with pH manipulation can be preferable chromatographic conditions to be explored in the purification of plasmid DNA biopharmaceuticals, in order to avoid the environmental impact of ammonium sulfate. Copyright © 2014. Published by Elsevier B.V.

  7. Purification of influenza deoxyribonucleic acid-based vaccine using agmatine monolith.

    Science.gov (United States)

    Bicho, D; Caramelo-Nunes, C; Sousa, A; Sousa, F; Queiroz, J A; Tomaz, C T

    2016-02-15

    Lately, researchers have made several efforts to improve vaccine production to fight highly contagious respiratory diseases like influenza. One of the most promising options for reducing the impact of this virus is DNA vaccination. However, a large quantity of highly pure plasmid DNA (pDNA) is necessary to attain this goal. The present work describes the production and purification of the plasmid NTC7482-41H-VA2HA expressing influenza virus hemagglutinin using an agmatine monolith. This ligand was chosen to purify supercoiled (sc) pDNA from complex lysates because of its versatile multimodal character. Its natural intervention in several biological systems together with its similarity with the highly studied arginine ligand allowed the development of a simpler and more specific purification process. Agmatine works under two strategies: descending ammonium sulfate gradient and ascending sodium chloride gradient. Furthermore, pH manipulation revealed an important role in pDNA isoforms selectivity. Dynamic binding capacity (DBC) experiments were performed varying different parameters and showed an increase with pDNA concentration, while high flow rate and high pH had the opposite effect. Sc pDNA was purified with high yield and was efficient with respect to cell transfection and cell viability. This monolith showed to be appropriate to purify the plasmid NTC7482-41H-VA2HA, providing a valuable tool for pDNA influenza vaccines preparation. Copyright © 2016. Published by Elsevier B.V.

  8. Neuroprotective effect of agmatine in rats with transient cerebral ischemia using MR imaging and histopathologic evaluation.

    Science.gov (United States)

    Huang, Y C; Tzeng, W S; Wang, C C; Cheng, B C; Chang, Y K; Chen, H H; Lin, P C; Huang, T Y; Chuang, T J; Lin, J W; Chang, C P

    2013-09-01

    This study aimed to further investigate the effects of agmatine on brain edema in the rats with middle cerebral artery occlusion (MCAO) injury using magnetic resonance imaging (MRI) monitoring and biochemical and histopathologic evaluation. Following surgical induction of MCAO for 90min, agmatine was injected 5min after beginning of reperfusion and again once daily for the next 3 post-operative days. The events during ischemia and reperfusion were investigated by T2-weighted images (T2WI), serial diffusion-weighted images (DWI), calculated apparent diffusion coefficient (ADC) maps and contrast-enhanced T1-weighted images (CE-T1WI) during 3h-72h in a 1.5T Siemens MAGNETON Avanto Scanner. Lesion volumes were analyzed in a blinded and randomized manner. Triphenyltetrazolium chloride (TTC), Nissl, and Evans Blue stainings were performed at the corresponding sections. Increased lesion volumes derived from T2WI, DWI, ADC, CE-T1WI, and TTC all were noted at 3h and peaked at 24h-48h after MCAO injury. TTC-derived infarct volumes were not significantly different from the T2WI, DWI-, and CE-T1WI-derived lesion volumes at the last imaging time (72h) point except for significantly smaller ADC lesions in the MCAO model (Pagmatine-treated rats compared with the control ischemia rats (Pagmatine has neuroprotective effects against brain edema on a reperfusion model after transient cerebral ischemia. Copyright © 2013 Elsevier Inc. All rights reserved.

  9. Bradykinin-potentiating PEPTIDE-10C, an argininosuccinate synthetase activator, protects against H2O2-induced oxidative stress in SH-SY5Y neuroblastoma cells.

    Science.gov (United States)

    Querobino, Samyr Machado; Ribeiro, César Augusto João; Alberto-Silva, Carlos

    2018-05-01

    Bradykinin-potentiating peptides (BPPs - 5a, 7a, 9a, 10c, 11e, and 12b) of Bothrops jararaca (Bj) were described as argininosuccinate synthase (AsS) activators, improving l-arginine availability. Agmatine and polyamines, which are l-arginine metabolism products, have neuroprotective properties. Here, we investigated the neuroprotective effects of low molecular mass fraction from Bj venom (LMMF) and two synthetic BPPs (BPP-10c, BPP-12b, BPP-10c showed higher protective capacity than BPP-12b. LMMF pretreatment was unable to prevent the reduction of cell viability caused by H 2 O 2 . The neuroprotective mechanism of BPP-10c against oxidative stress was investigated. BPP-10c reduced ROS generation and lipid peroxidation in relation to cells treated only with H 2 O 2 . BBP-10c increased AsS expression and was not neuroprotective in the presence of MDLA, a specific inhibitor of AsS. BPP-10c reduced iNOS expression and nitrate levels but decreased NF-kB expression. Furthermore, BPP-10c protected the mitochondrial membrane against oxidation. Overall, we demonstrated for the first time neuroprotective mechanisms of BPPs against oxidative stress, opening new perspectives to the study and application of these peptides for the treatment of neurodegenerative diseases. Copyright © 2018 Elsevier Inc. All rights reserved.

  10. The Effect of Agmatine on Expression of IL-1β and TLX Which Promotes Neuronal Differentiation in Lipopolysaccharide-Treated Neural Progenitors.

    Science.gov (United States)

    Song, Juhyun; Kumar, Bokara Kiran; Kang, Somang; Park, Kyung Ah; Lee, Won Taek; Lee, Jong Eun

    2013-12-01

    Differentiation of neural progenitor cells (NPCs) is important for protecting neural cells and brain tissue during inflammation. Interleukin-1 beta (IL-1β) is the most common pro- inflammatory cytokine in brain inflammation, and increased IL-1β levels can decrease the proliferation of NPCs. We aimed to investigate whether agmatine (Agm), a primary polyamine that protects neural cells, could trigger differentiation of NPCs by activating IL-1β in vitro. The cortex of ICR mouse embryos (E14) was dissociated to culture NPCs. NPCs were stimulated by lipopolysaccharide (LPS). After 6 days, protein expression of stem cell markers and differentiation signal factors was confirmed by using western blot analysis. Also, immunocytochemistry was used to confirm the cell fate. Agm treatment activated NPC differentiation significantly more than in the control group, which was evident by the increased expression of a neuronal marker, MAP2, in the LPS-induced, Agm-treated group. Differentiation of LPS-induced, Agm-treated NPCs was regulated by the MAPK pathway and is thought to be related to IL-1β activation and decreased expression of TLX, a transcription factor that regulates NPC differentiation. Our results reveal that Agm can promote NPC differentiation to neural stem cells by modulating IL-1β expression under inflammatory condition, and they suggest that Agm may be a novel therapeutic strategy for neuroinflammatory diseases.

  11. Methods for pretreating biomass

    Science.gov (United States)

    Balan, Venkatesh; Dale, Bruce E; Chundawat, Shishir; Sousa, Leonardo

    2017-05-09

    A method for pretreating biomass is provided, which includes, in a reactor, allowing gaseous ammonia to condense on the biomass and react with water present in the biomass to produce pretreated biomass, wherein reactivity of polysaccharides in the biomass is increased during subsequent biological conversion as compared to the reactivity of polysaccharides in biomass which has not been pretreated. A method for pretreating biomass with a liquid ammonia and recovering the liquid ammonia is also provided. Related systems which include a biochemical or biofuel production facility are also disclosed.

  12. 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

  13. Improved method for HPLC analysis of polyamines, agmatine and aromatic monoamines in plant tissue

    Science.gov (United States)

    Slocum, R. D.; Flores, H. E.; Galston, A. W.; Weinstein, L. H.

    1989-01-01

    The high performance liquid chromatographic (HPLC) method of Flores and Galston (1982 Plant Physiol 69: 701) for the separation and quantitation of benzoylated polyamines in plant tissues has been widely adopted by other workers. However, due to previously unrecognized problems associated with the derivatization of agmatine, this important intermediate in plant polyamine metabolism cannot be quantitated using this method. Also, two polyamines, putrescine and diaminopropane, also are not well resolved using this method. A simple modification of the original HPLC procedure greatly improves the separation and quantitation of these amines, and further allows the simulation analysis of phenethylamine and tyramine, which are major monoamine constituents of tobacco and other plant tissues. We have used this modified HPLC method to characterize amine titers in suspension cultured carrot (Daucas carota L.) cells and tobacco (Nicotiana tabacum L.) leaf tissues.

  14. Agmatine Reverses Sub-chronic Stress induced Nod-like Receptor Protein 3 (NLRP3) Activation and Cytokine Response in Rats.

    Science.gov (United States)

    Sahin, Ceren; Albayrak, Ozgur; Akdeniz, Tuğba F; Akbulut, Zeynep; Yanikkaya Demirel, Gulderen; Aricioglu, Feyza

    2016-10-01

    The activation of Nod-like receptor protein 3 (NLRP3) has lately been implicated in stress and depression as an initiator mechanism required for the production of interleukin (IL)-1β and IL-18. Agmatine, an endogenous polyamine widely distributed in mammalian brain, is a novel neurotransmitter/neuromodulator, with antistress, anxiolytic and antidepressant-like effects. In this study, we examined the effect of exogenously administered agmatine on NLRP3 inflammasome pathway/cytokine responses in rats exposed to restraint stress for 7 days. The rats were divided into three groups: stress, stress+agmatine (40 mg/kg; i.p.) and control groups. Agmatine significantly down-regulated the gene expressions of all stress-induced NLRP3 inflammasome components (NLRP3, NF-κB, PYCARD, caspase-1, IL-1β and IL-18) in the hippocampus and prefrontal cortex (PFC) and reduced pro-inflammatory cytokine levels not only in both brain regions, but also in serum. Stress-reduced levels of IL-4 and IL-10, two major anti-inflammatory cytokines, were restored back to normal by agmatine treatment in the PFC. The findings of the present study suggest that stress-activated NLRP3 inflammasome and cytokine responses are reversed by an acute administration of agmatine. Whether antidepressant-like effect of agmatine can somehow, at least partially, be mediated by the inhibition of NLRP3 inflammasome cascade and relevant inflammatory responses requires further studies in animal models of depression. © 2016 Nordic Association for the Publication of BCPT (former Nordic Pharmacological Society).

  15. Corrosion protection and adhesion properties of the epoxy coating applied on the steel substrate pre-treated by a sol-gel based silane coating filled with amino and isocyanate silane functionalized graphene oxide nanosheets

    Science.gov (United States)

    Parhizkar, Nafise; Ramezanzadeh, Bahram; Shahrabi, Taghi

    2018-05-01

    This research has focused on the effect of graphene oxide (GO) nano-fillers embedded in the sol-gel based silane coating on the corrosion protection and adhesion properties of the epoxy coating applied on the steel substrate pre-treated by silane coatings. For this purpose, a mixture of Methyltriethoxysilane (MTES) and Tetraethylorthosilicate (TEOS) silane precursors was used for preparation of composite matrix and the GO nanosheets, which are covalently functionalized with 3-(Triethoxysilyl)propyl isocyanate (TEPI, IGO nano-fillers) and 3-aminopropyltriethoxysilane (APTES, AGO nano-fillers), were used as filler. The GO, AGO and IGO nanosheets were characterized by Fourier Transform Infrared Spectroscopy (FT-IR), UV-Visible analysis and field emission-scanning electron microscopy techniques. The performance of the silane/epoxy coatings was investigated by pull-off adhesion, cathodic delamination, salt spray and electrochemical impedance spectroscopy (EIS) tests. Results revealed that AGO and IGO nano-fillers significantly improved the corrosion resistance and adhesion properties of the top epoxy coating due to better compatibility with silane matrix, excellent barrier properties and the formation of covalent bonds with the top epoxy coating.

  16. 40 CFR 407.14 - Pretreatment standards for existing sources.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 28 2010-07-01 2010-07-01 true Pretreatment standards for existing sources. 407.14 Section 407.14 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS CANNED AND PRESERVED FRUITS AND VEGETABLES PROCESSING POINT SOURCE...

  17. 40 CFR 407.34 - Pretreatment standards for existing sources.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 28 2010-07-01 2010-07-01 true Pretreatment standards for existing sources. 407.34 Section 407.34 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS CANNED AND PRESERVED FRUITS AND VEGETABLES PROCESSING POINT SOURCE...

  18. 40 CFR 407.24 - Pretreatment standards for existing sources.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 28 2010-07-01 2010-07-01 true Pretreatment standards for existing sources. 407.24 Section 407.24 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS CANNED AND PRESERVED FRUITS AND VEGETABLES PROCESSING POINT SOURCE...

  19. 40 CFR 407.26 - Pretreatment standards for new sources.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 28 2010-07-01 2010-07-01 true Pretreatment standards for new sources. 407.26 Section 407.26 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS CANNED AND PRESERVED FRUITS AND VEGETABLES PROCESSING POINT SOURCE CATEGORY Apple...

  20. 40 CFR 407.16 - Pretreatment standards for new sources.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 28 2010-07-01 2010-07-01 true Pretreatment standards for new sources. 407.16 Section 407.16 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS CANNED AND PRESERVED FRUITS AND VEGETABLES PROCESSING POINT SOURCE CATEGORY Apple...

  1. 40 CFR 406.36 - Pretreatment standards for new sources.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 28 2010-07-01 2010-07-01 true Pretreatment standards for new sources. 406.36 Section 406.36 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS GRAIN MILLS POINT SOURCE CATEGORY Normal Wheat Flour Milling Subcategory § 406.36...

  2. 40 CFR 406.14 - Pretreatment standards for existing sources.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 28 2010-07-01 2010-07-01 true Pretreatment standards for existing sources. 406.14 Section 406.14 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS GRAIN MILLS POINT SOURCE CATEGORY Corn Wet Milling Subcategory § 406.14...

  3. 40 CFR 406.46 - Pretreatment standards for new sources.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 28 2010-07-01 2010-07-01 true Pretreatment standards for new sources. 406.46 Section 406.46 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS GRAIN MILLS POINT SOURCE CATEGORY Bulgur Wheat Flour Milling Subcategory § 406.46...

  4. 40 CFR 406.24 - Pretreatment standards for existing sources.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 28 2010-07-01 2010-07-01 true Pretreatment standards for existing sources. 406.24 Section 406.24 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS GRAIN MILLS POINT SOURCE CATEGORY Corn Dry Milling Subcategory § 406.24...

  5. 40 CFR 427.46 - Pretreatment standards for new sources.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Pretreatment standards for new sources. 427.46 Section 427.46 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS ASBESTOS MANUFACTURING POINT SOURCE CATEGORY Asbestos Paper (Elastomeric Binder...

  6. 40 CFR 427.36 - Pretreatment standards for new sources.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Pretreatment standards for new sources. 427.36 Section 427.36 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS ASBESTOS MANUFACTURING POINT SOURCE CATEGORY Asbestos Paper (Starch Binder...

  7. 40 CFR 417.86 - Pretreatment standards for new sources.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 28 2010-07-01 2010-07-01 true Pretreatment standards for new sources. 417.86 Section 417.86 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS SOAP AND DETERGENT MANUFACTURING POINT SOURCE CATEGORY Manufacture of Liquid Soaps...

  8. 40 CFR 425.04 - Applicability of sulfide pretreatment standards.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Applicability of sulfide pretreatment standards. 425.04 Section 425.04 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS LEATHER TANNING AND FINISHING POINT SOURCE CATEGORY General Provisions...

  9. 40 CFR 428.66 - Pretreatment standards for new sources.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Pretreatment standards for new sources. 428.66 Section 428.66 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS RUBBER MANUFACTURING POINT SOURCE CATEGORY Medium-Sized General Molded, Extruded...

  10. Agmatine ameliorates type 2 diabetes induced-Alzheimer's disease-like alterations in high-fat diet-fed mice via reactivation of blunted insulin signalling.

    Science.gov (United States)

    Kang, Somang; Kim, Chul-Hoon; Jung, Hosung; Kim, Eosu; Song, Ho-Taek; Lee, Jong Eun

    2017-02-01

    The risk of Alzheimer's disease (AD) is higher in patients with type 2 diabetes mellitus (T2DM). Previous studies in high-fat diet-induced AD animal models have shown that brain insulin resistance in these animals leads to the accumulation of amyloid beta (Aβ) and the reduction in GSK-3β phosphorylation, which promotes tau phosphorylation to cause AD. No therapeutic treatments that target AD in T2DM patients have yet been discovered. Agmatine, a primary amine derived from l-arginine, has exhibited anti-diabetic effects in diabetic animals. The aim of this study was to investigate the ability of agmatine to treat AD induced by brain insulin resistance. ICR mice were fed a 60% high-fat diet for 12 weeks and received one injection of streptozotocin (100 mg/kg/ip) 4 weeks into the diet. After the 12-week diet, the mice were treated with agmatine (100 mg/kg/ip) for 2 weeks. Behaviour tests were conducted prior to sacrifice. Brain expression levels of the insulin signal molecules p-IRS-1, p-Akt, and p-GSK-3β and the accumulation of Aβ and p-tau were evaluated. Agmatine administration rescued the reduction in insulin signalling, which in turn reduced the accumulation of Aβ and p-tau in the brain. Furthermore, agmatine treatment also reduced cognitive decline. Agmatine attenuated the occurrence of AD in T2DM mice via the activation of the blunted insulin signal. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  11. Atlantic salmon endothelial cells from the heart were more susceptible than fibroblasts from the bulbus arteriosus to four RNA viruses but protected from two viruses by dsRNA pretreatment.

    Science.gov (United States)

    Pham, Phuc H; Tong, Winnie W L; Misk, Ehab; Jones, Ginny; Lumsden, John S; Bols, Niels C

    2017-11-01

    Heart diseases caused by viruses are major causes of Atlantic salmon aquaculture loss. Two Atlantic salmon cardiovascular cell lines, an endothelial cell line (ASHe) from the heart and a fibroblast cell line (BAASf) from the bulbus arteriosus, were evaluated for their response to four fish viruses, CSV, IPNV, VHSV IVa and VHSV IVb, and the innate immune agonist, double-stranded RNA mimic poly IC. All four viruses caused cytopathic effects in ASHe and BAASf. However, ASHe was more susceptible to all four viruses than BAASf. When comparing between the viruses, ASHe cells were found to be moderately susceptible to CSV and VHSV IVb, but highly susceptible to IPNV and VHSV IVa induced cell death. All four viruses were capable of propagating in the ASHe cell line, leading to increases in virus titre over time. In BAASf, CSV and IPNV produced more than one log increase in titre from initial infection, but VHSV IVb and IVa did not. When looking at the antiviral response of both cell lines, Mx proteins were induced in ASHe and BAASf by poly IC. All four viruses induced Mx proteins in BAASf, while only CSV and VHSV IVb induced Mx proteins in ASHe. IPNV and VHSV IVa suppressed Mx proteins expression in ASHe. Pretreatment of ASHe with poly IC to allow for Mx proteins accumulation protected the culture from subsequent infections with IPNV and VHSV IVa, resulting in delayed cell death, reduced virus titres and reduced viral proteins expression. These data suggest that endothelial cells potentially can serve as points of infections for viruses in the heart and that two of the four viruses, IPNV and VHSV IVa, have mechanisms to avoid or downregulate antiviral responses in ASHe cells. Furthermore, the high susceptibility of the ASHe cell line to IPNV and VHSV IVa can make it a useful tool for studying antiviral compounds against these viruses and for general detection of fish viruses. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. GREET Pretreatment Module

    Energy Technology Data Exchange (ETDEWEB)

    Adom, Felix K. [Argonne National Lab. (ANL), Argonne, IL (United States). Energy Systems Division; Dunn, Jennifer B. [Argonne National Lab. (ANL), Argonne, IL (United States). Energy Systems Division; Han, Jeongwoo [Argonne National Lab. (ANL), Argonne, IL (United States). Energy Systems Division

    2014-09-01

    A wide range of biofuels and biochemicals can be produced from cellulosic biomass via different pretreatment technologies that yield sugars. Process simulations of dilute acid and ammonia fiber expansion pretreatment processes and subsequent hydrolysis were developed in Aspen Plus for four lignocellulosic feedstocks (corn stover, miscanthus, switchgrass, and poplar). This processing yields sugars that can be subsequently converted to biofuels or biochemical. Material and energy consumption data from Aspen Plus were then compiled in a new Greenhouses Gases, Regulated Emissions, and Energy Use in Transportation (GREETTM) pretreatment module. The module estimates the cradle-to-gate fossil energy consumption (FEC) and greenhouse gas (GHG) emissions associated with producing fermentable sugars. This report documents the data and methodology used to develop this module and the cradle-to-gate FEC and GHG emissions that result from producing fermentable sugars.

  13. PRETREATING THORIUM FOR ELECTROPLATING

    Science.gov (United States)

    Beach, J.G.; Schaer, G.R.

    1959-07-28

    A method is presented for pretreating a thorium surface prior to electroplating the surface. The pretreatment steps of the invention comprise cleaning by vapor blasting the surface, anodically pickling in a 5 to 15% by volume aqueous hydrochloric acid bath with a current of 125 to 250 amp/sq ft for 3 to 5 min at room temperature, chemically pickling the surface in a 5 to 15% by volume of aqueous sulfuric acid for 3 to 5 min at room temperature, and rinsing the surface with water.

  14. Molecular mechanism of pH-dependent substrate transport by an arginine-agmatine antiporter.

    Science.gov (United States)

    Wang, Sheng; Yan, Renhong; Zhang, Xi; Chu, Qi; Shi, Yigong

    2014-09-02

    Enteropathogenic bacteria, exemplified by Escherichia coli, rely on acid-resistance systems (ARs) to survive the acidic environment of the stomach. AR3 consumes intracellular protons through decarboxylation of arginine (Arg) in the cytoplasm and exchange of the reaction product agmatine (Agm) with extracellular Arg. The latter process is mediated by the Arg:Agm antiporter AdiC, which is activated in response to acidic pH and remains fully active at pH 6.0 and below. Despite our knowledge of structural information, the molecular mechanism by which AdiC senses acidic pH remains completely unknown. Relying on alanine-scanning mutagenesis and an in vitro proteoliposome-based transport assay, we have identified Tyr74 as a critical pH sensor in AdiC. The AdiC variant Y74A exhibited robust transport activity at all pH values examined while maintaining stringent substrate specificity for Arg:Agm. Replacement of Tyr74 by Phe, but not by any other amino acid, led to the maintenance of pH-dependent substrate transport. These observations, in conjunction with structural information, identify a working model for pH-induced activation of AdiC in which a closed conformation is disrupted by cation-π interactions between proton and the aromatic side chain of Tyr74.

  15. Poly(Amido Amine)s Containing Agmatine and Butanol Side Chains as Efficient Gene Carriers.

    Science.gov (United States)

    Won, Young-Wook; Ankoné, Marc; Engbersen, Johan F J; Feijen, Jan; Kim, Sung Wan

    2016-04-01

    A new type of bioreducible poly(amido amine) copolymer is synthesized by the Michael addition polymerization of cystamine bisacrylamide (CBA) with 4-aminobutylguanidine (agmatine, AGM) and 4-aminobutanol (ABOL). Since the positively charged guanidinium groups of AGM and the hydroxybutyl groups of ABOL in the side chains have shown to improve the overall transfection efficiency of poly(amido amine)s, it is hypothesized that poly(CBA-ABOL/AGM) synthesized at the optimal ratio of both components would result in high transfection efficiency and minimal toxicity. In this study, a series of the poly(CBA-ABOL/AGM) copolymers is synthesized as gene carriers. The polymers are characterized and luciferase transfection efficiencies of the polymers in various cell lines are investigated to select the ideal ratio between AGM and ABOL. The poly(CBA-ABOL/AGM) containing 80% AGM and 20% ABOL has shown the best transfection efficiency with the lowest cytotoxicity, indicating that this polymer is very promising as a potent and nontoxic gene carrier. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Protective

    Directory of Open Access Journals (Sweden)

    Wessam M. Abdel-Wahab

    2013-10-01

    Full Text Available Many active ingredients extracted from herbal and medicinal plants are extensively studied for their beneficial effects. Antioxidant activity and free radical scavenging properties of thymoquinone (TQ have been reported. The present study evaluated the possible protective effects of TQ against the toxicity and oxidative stress of sodium fluoride (NaF in the liver of rats. Rats were divided into four groups, the first group served as the control group and was administered distilled water whereas the NaF group received NaF orally at a dose of 10 mg/kg for 4 weeks, TQ group was administered TQ orally at a dose of 10 mg/kg for 5 weeks, and the NaF-TQ group was first given TQ for 1 week and was secondly administered 10 mg/kg/day NaF in association with 10 mg/kg TQ for 4 weeks. Rats intoxicated with NaF showed a significant increase in lipid peroxidation whereas the level of reduced glutathione (GSH and the activity of superoxide dismutase (SOD, catalase (CAT, glutathione S-transferase (GST and glutathione peroxidase (GPx were reduced in hepatic tissues. The proper functioning of the liver was also disrupted as indicated by alterations in the measured liver function indices and biochemical parameters. TQ supplementation counteracted the NaF-induced hepatotoxicity probably due to its strong antioxidant activity. In conclusion, the results obtained clearly indicated the role of oxidative stress in the induction of NaF toxicity and suggested hepatoprotective effects of TQ against the toxicity of fluoride compounds.

  17. The multifaceted effects of agmatine on functional recovery after spinal cord injury through Modulations of BMP-2/4/7 expressions in neurons and glial cells.

    Directory of Open Access Journals (Sweden)

    Yu Mi Park

    Full Text Available Presently, few treatments for spinal cord injury (SCI are available and none have facilitated neural regeneration and/or significant functional improvement. Agmatine (Agm, a guanidinium compound formed from decarboxylation of L-arginine by arginine decarboxylase, is a neurotransmitter/neuromodulator and been reported to exert neuroprotective effects in central nervous system injury models including SCI. The purpose of this study was to demonstrate the multifaceted effects of Agm on functional recovery and remyelinating events following SCI. Compression SCI in mice was produced by placing a 15 g/mm(2 weight for 1 min at thoracic vertebra (Th 9 segment. Mice that received an intraperitoneal (i.p. injection of Agm (100 mg/kg/day within 1 hour after SCI until 35 days showed improvement in locomotor recovery and bladder function. Emphasis was made on the analysis of remyelination events, neuronal cell preservation and ablation of glial scar area following SCI. Agm treatment significantly inhibited the demyelination events, neuronal loss and glial scar around the lesion site. In light of recent findings that expressions of bone morphogenetic proteins (BMPs are modulated in the neuronal and glial cell population after SCI, we hypothesized whether Agm could modulate BMP- 2/4/7 expressions in neurons, astrocytes, oligodendrocytes and play key role in promoting the neuronal and glial cell survival in the injured spinal cord. The results from computer assisted stereological toolbox analysis (CAST demonstrate that Agm treatment dramatically increased BMP- 2/7 expressions in neurons and oligodendrocytes. On the other hand, BMP- 4 expressions were significantly decreased in astrocytes and oligodendrocytes around the lesion site. Together, our results reveal that Agm treatment improved neurological and histological outcomes, induced oligodendrogenesis, protected neurons, and decreased glial scar formation through modulating the BMP- 2/4/7 expressions following

  18. The Multifaceted Effects of Agmatine on Functional Recovery after Spinal Cord Injury through Modulations of BMP-2/4/7 Expressions in Neurons and Glial Cells

    Science.gov (United States)

    Park, Yu Mi; Lee, Won Taek; Bokara, Kiran Kumar; Seo, Su Kyoung; Park, Seung Hwa; Kim, Jae Hwan; Yenari, Midori A.; Park, Kyung Ah; Lee, Jong Eun

    2013-01-01

    Presently, few treatments for spinal cord injury (SCI) are available and none have facilitated neural regeneration and/or significant functional improvement. Agmatine (Agm), a guanidinium compound formed from decarboxylation of L-arginine by arginine decarboxylase, is a neurotransmitter/neuromodulator and been reported to exert neuroprotective effects in central nervous system injury models including SCI. The purpose of this study was to demonstrate the multifaceted effects of Agm on functional recovery and remyelinating events following SCI. Compression SCI in mice was produced by placing a 15 g/mm2 weight for 1 min at thoracic vertebra (Th) 9 segment. Mice that received an intraperitoneal (i.p.) injection of Agm (100 mg/kg/day) within 1 hour after SCI until 35 days showed improvement in locomotor recovery and bladder function. Emphasis was made on the analysis of remyelination events, neuronal cell preservation and ablation of glial scar area following SCI. Agm treatment significantly inhibited the demyelination events, neuronal loss and glial scar around the lesion site. In light of recent findings that expressions of bone morphogenetic proteins (BMPs) are modulated in the neuronal and glial cell population after SCI, we hypothesized whether Agm could modulate BMP- 2/4/7 expressions in neurons, astrocytes, oligodendrocytes and play key role in promoting the neuronal and glial cell survival in the injured spinal cord. The results from computer assisted stereological toolbox analysis (CAST) demonstrate that Agm treatment dramatically increased BMP- 2/7 expressions in neurons and oligodendrocytes. On the other hand, BMP- 4 expressions were significantly decreased in astrocytes and oligodendrocytes around the lesion site. Together, our results reveal that Agm treatment improved neurological and histological outcomes, induced oligodendrogenesis, protected neurons, and decreased glial scar formation through modulating the BMP- 2/4/7 expressions following SCI. PMID

  19. Zinc-induced protection against cadmium

    Energy Technology Data Exchange (ETDEWEB)

    Early, J.L.; Schnell, R.C.

    1978-02-01

    Pretreatment of male rats with cadmium acetate potentiates the duration of hexobarbital hypnosis and inhibits the rate of hepatic microsomal drug metabolism. Pretreatment of rats with zinc acetate protects against these alterations in drug action elicited by cadmium.

  20. AguR is a transmembrane transcription activator of the putrescine biosynthesis operon in Lactococcus lactis, and acts in response to agmatine concentration

    NARCIS (Netherlands)

    Linares, Daniel M; Del Rio, Beatriz; Redruello, Begoña; Ladero, Victor; Martin, Ma Cruz; de Jong, Anne; Kuipers, Oscar P; Fernandez, Maria; Alvarez, Miguel A

    2015-01-01

    Dairy industry fermentative processes mostly use Lactococcus lactis as a starter. However, some dairy L. lactis strains produce putrescine - a biogenic amine that raises food safety and spoilage concerns - via the agmatine deiminase pathway (AGDI). The enzymatic activities responsible for putrescine

  1. Biomass shock pretreatment

    Science.gov (United States)

    Holtzapple, Mark T.; Madison, Maxine Jones; Ramirez, Rocio Sierra; Deimund, Mark A.; Falls, Matthew; Dunkelman, John J.

    2014-07-01

    Methods and apparatus for treating biomass that may include introducing a biomass to a chamber; exposing the biomass in the chamber to a shock event to produce a shocked biomass; and transferring the shocked biomass from the chamber. In some aspects, the method may include pretreating the biomass with a chemical before introducing the biomass to the chamber and/or after transferring shocked biomass from the chamber.

  2. Agmatine Improves Cognitive Dysfunction and Prevents Cell Death in a Streptozotocin-Induced Alzheimer Rat Model

    Science.gov (United States)

    Song, Juhyun; Hur, Bo Eun; Bokara, Kiran Kumar; Yang, Wonsuk; Cho, Hyun Jin; Park, Kyung Ah; Lee, Won Taek; Lee, Kyoung Min

    2014-01-01

    Purpose Alzheimer's disease (AD) results in memory impairment and neuronal cell death in the brain. Previous studies demonstrated that intracerebroventricular administration of streptozotocin (STZ) induces pathological and behavioral alterations similar to those observed in AD. Agmatine (Agm) has been shown to exert neuroprotective effects in central nervous system disorders. In this study, we investigated whether Agm treatment could attenuate apoptosis and improve cognitive decline in a STZ-induced Alzheimer rat model. Materials and Methods We studied the effect of Agm on AD pathology using a STZ-induced Alzheimer rat model. For each experiment, rats were given anesthesia (chloral hydrate 300 mg/kg, ip), followed by a single injection of STZ (1.5 mg/kg) bilaterally into each lateral ventricle (5 µL/ventricle). Rats were injected with Agm (100 mg/kg) daily up to two weeks from the surgery day. Results Agm suppressed the accumulation of amyloid beta and enhanced insulin signal transduction in STZ-induced Alzheimer rats [experimetal control (EC) group]. Upon evaluation of cognitive function by Morris water maze testing, significant improvement of learning and memory dysfunction in the STZ-Agm group was observed compared with the EC group. Western blot results revealed significant attenuation of the protein expressions of cleaved caspase-3 and Bax, as well as increases in the protein expressions of Bcl2, PI3K, Nrf2, and γ-glutamyl cysteine synthetase, in the STZ-Agm group. Conclusion Our results showed that Agm is involved in the activation of antioxidant signaling pathways and activation of insulin signal transduction. Accordingly, Agm may be a promising therapeutic agent for improving cognitive decline and attenuating apoptosis in AD. PMID:24719136

  3. ASIC3 Channels Integrate Agmatine and Multiple Inflammatory Signals through the Nonproton Ligand Sensing Domain

    Directory of Open Access Journals (Sweden)

    Cao Hui

    2010-12-01

    Full Text Available Abstract Background Acid-sensing ion channels (ASICs have long been known to sense extracellular protons and contribute to sensory perception. Peripheral ASIC3 channels represent natural sensors of acidic and inflammatory pain. We recently reported the use of a synthetic compound, 2-guanidine-4-methylquinazoline (GMQ, to identify a novel nonproton sensing domain in the ASIC3 channel, and proposed that, based on its structural similarity with GMQ, the arginine metabolite agmatine (AGM may be an endogenous nonproton ligand for ASIC3 channels. Results Here, we present further evidence for the physiological correlation between AGM and ASIC3. Among arginine metabolites, only AGM and its analog arcaine (ARC activated ASIC3 channels at neutral pH in a sustained manner similar to GMQ. In addition to the homomeric ASIC3 channels, AGM also activated heteromeric ASIC3 plus ASIC1b channels, extending its potential physiological relevance. Importantly, the process of activation by AGM was highly sensitive to mild acidosis, hyperosmolarity, arachidonic acid (AA, lactic acid and reduced extracellular Ca2+. AGM-induced ASIC3 channel activation was not through the chelation of extracellular Ca2+ as occurs with increased lactate, but rather through a direct interaction with the newly identified nonproton ligand sensing domain. Finally, AGM cooperated with the multiple inflammatory signals to cause pain-related behaviors in an ASIC3-dependent manner. Conclusions Nonproton ligand sensing domain might represent a novel mechanism for activation or sensitization of ASIC3 channels underlying inflammatory pain-sensing under in vivo conditions.

  4. PROJECT W-551 INTERIM PRETREATMENT SYSTEM PRECONCEPTUAL CANDIDATE TECHNOLOGY DESCRIPTIONS

    Energy Technology Data Exchange (ETDEWEB)

    MAY TH

    2008-08-12

    The Office of River Protection (ORP) has authorized a study to recommend and select options for interim pretreatment of tank waste and support Waste Treatment Plant (WTP) low activity waste (LAW) operations prior to startup of all the WTP facilities. The Interim Pretreatment System (IPS) is to be a moderately sized system which separates entrained solids and 137Cs from tank waste for an interim time period while WTP high level waste vitrification and pretreatment facilities are completed. This study's objective is to prepare pre-conceptual technology descriptions that expand the technical detail for selected solid and cesium separation technologies. This revision includes information on additional feed tanks.

  5. Radioprotection of mice following garlic pretreatment

    International Nuclear Information System (INIS)

    Singh, S.P.; Abraham, S.K.; Kesavan, P.C.

    1996-01-01

    Freshly prepared aqueous extract of garlic was tested in mice for its possible in vivo protective effect against gamma-radiation-induced chromosomal damage. In the same animals, the changes in the sulphydryl content and glutathione S-transferase activity were evaluated. Three doses of garlic extract [125, 250 and 500 mg kg-1 body weight (bw)] were administered orally for five consecutive days and the animals were exposed to 0.25, 0.5, 1.0 and 2.0 Gy gamma-radiation 2 h after the final feeding. The results of the bone marrow micronucleus test revealed that pretreatment with garlic extract was effective in reducing gamma-radiation-induced chromosomal damage. Against 0.25 Gy gamma-radiation, a high dose of 500 mg kg-1 bw garlic extract was required to significantly reduce the chromosomal damage. All the three doses of garlic extract were effective in exerting a protective effect against 0.5, 1.0 and 2.0 Gy gamma-radiation. However a dose-related effect was observed only against 2.0 Gy. The sulphydryl content and glutathione S-transferase activity registered a significant increase after either pretreatment with garlic with extract or irradiation. In the garlic extract pretreated irradiated animals, a significant reduction was observed in the sulphydryl content and glutathione S-transferase activity

  6. Electrolytic pretreatment of urine

    Science.gov (United States)

    1977-01-01

    Electrolysis has been under evaluation for several years as a process to pretreat urine for ultimate recovery of potable water in manned spacecraft applications. The conclusions that were drawn from this investigation are the following: (1) A platinum alloy containing 10 percent rhodium has been shown to be an effective, corrosion-resistant anode material for the electrolytic pretreatment of urine. Black platinum has been found to be suitable as a cathode material. (2) The mechanism of the reactions occurring during the electrolysis of urine is two-stage: (a) a total Kjeldahl nitrogen and total organic carbon (TOC) removal in the first stage is the result of electrochemical oxidation of urea to CO2, H2O, and ammonia followed by chloride interaction to produce N2 from ammonia, (b) after the urea has been essentially removed and the chloride ions have no more ammonia to interact with, the chloride ions start to oxidize to higher valence states, thus producing perchlorates. (3) Formation of perchlorates can be suppressed by high/low current operation, elevated temperature, and pH adjustment. (4) UV-radiation showed promise in assisting electrolytic TOC removal in beaker tests, but was not substantiated in limited single cell testing. This may have been due to non-optimum configurations of the single cell test rig and the light source.

  7. Prevalence of the lmo0036-0043 gene cluster encoding arginine deiminase and agmatine deiminase systems in Listeria monocytogenes.

    Science.gov (United States)

    Chen, Jianshun; Chen, Fan; Cheng, Changyong; Fang, Weihuan

    2013-04-01

    Arginine deiminase and agmatine deiminase systems are involved in acid tolerance, and their encoding genes form the cluster lmo0036-0043 in Listeria monocytogenes. While lmo0042 and lmo0043 were conserved in all L. monocytogenes strains, the lmo0036-0041 region of this cluster was identified in all lineages I and II, and the majority of lineage IV (83.3%) strains, but absent in all lineage III and a small fraction of lineage IV (16.7%) strains, suggesting that the presence of the complete lmo0036-0043 cluster is dependent on lineages. lmo0036-0043-complete and -deficient lineage IV strains exhibit specific ascB-dapE profiles, which might represent two subpopulations with distinct genetic characteristics.

  8. 2-D DIGE proteomic profiles of three strains of Fusarium graminearum grown in agmatine or glutamic acid medium

    Directory of Open Access Journals (Sweden)

    Tommaso Serchi

    2016-03-01

    Full Text Available 2D DIGE proteomics data obtained from three strains belonging to Fusarium graminearum s.s. species growing in a glutamic acid or agmatine containing medium are provided.A total of 381 protein species have been identified which do differ for abundance among the two treatments and among the strains (ANOVA±1.3.Data on the diversity of protein species profiles between the two media for each strain are made available. Shared profiles among strains are discussed in Pasquali et al. [1].Here proteins that with diverse profile can be used to differentiate strains are highlighted. The full dataset allow to obtaining single strain proteomic profiles. Keywords: Comparative strain proteomics, Toxigenic fungi, Polyamines, Trichothecenes, Strain variability

  9. AguR, a Transmembrane Transcription Activator of the Putrescine Biosynthesis Operon in Lactococcus lactis, Acts in Response to the Agmatine Concentration.

    Science.gov (United States)

    Linares, Daniel M; Del Rio, Beatriz; Redruello, Begoña; Ladero, Victor; Martin, M Cruz; de Jong, Anne; Kuipers, Oscar P; Fernandez, Maria; Alvarez, Miguel A

    2015-09-01

    Dairy industry fermentative processes mostly use Lactococcus lactis as a starter. However, some dairy L. lactis strains produce putrescine, a biogenic amine that raises food safety and spoilage concerns, via the agmatine deiminase (AGDI) pathway. The enzymatic activities responsible for putrescine biosynthesis in this bacterium are encoded by the AGDI gene cluster. The role of the catabolic genes aguB, aguD, aguA, and aguC has been studied, but knowledge regarding the role of aguR (the first gene in the cluster) remains limited. In the present work, aguR was found to be a very low level constitutively expressed gene that is essential for putrescine biosynthesis and is transcribed independently of the polycistronic mRNA encoding the catabolic genes (aguBDAC). In response to agmatine, AguR acts as a transcriptional activator of the aguB promoter (PaguB), which drives the transcription of the aguBDAC operon. Inverted sequences required for PaguB activity were identified by deletion analysis. Further work indicated that AguR is a transmembrane protein which might function as a one-component signal transduction system that senses the agmatine concentration of the medium and, accordingly, regulates the transcription of the aguBDAC operon through a C-terminal cytoplasmic DNA-binding domain typically found in LuxR-like proteins. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  10. Expression of the agmatine deiminase pathway in Enterococcus faecalis is activated by the AguR regulator and repressed by CcpA and PTS(Man systems.

    Directory of Open Access Journals (Sweden)

    Cristian Suárez

    Full Text Available Although the agmatine deiminase system (AgDI has been investigated in Enterococcus faecalis, little information is available with respect to its gene regulation. In this study we demonstrate that the presence of exogenous agmatine induces the expression of agu genes in this bacterium. In contrast to the homologous and extensively characterized AgDI system of S. mutants, the aguBDAC operon in E. faecalis is not induced in response to low pH. In spite of this, agmatine catabolism in this bacterium contributes by neutralizing the external medium while enhancing bacterial growth. Our results indicate that carbon catabolic repression (CCR operates on the AgDI system via a mechanism that involves interaction of CcpA and P-Ser-HPr with a cre site found in an unusual position considering the aguB promoter (55 nt upstream the +1 position. In addition, we found that components of the mannose phosphotransferase (PTS(Man system also contributed to CCR in E. faecalis since a complete relief of the PTS-sugars repressive effect was observed only in a PTS(Man and CcpA double defective strain. Our gene context analysis revealed that aguR is present in oral and gastrointestinal microorganisms. Thus, regulation of the aguBDAC operon in E. faecalis seems to have evolved to obtain energy and resist low pH conditions in order to persist and colonize gastrointestinal niches.

  11. Expression of the Agmatine Deiminase Pathway in Enterococcus faecalis Is Activated by the AguR Regulator and Repressed by CcpA and PTSMan Systems

    Science.gov (United States)

    Blancato, Víctor S.; Magni, Christian

    2013-01-01

    Although the agmatine deiminase system (AgDI) has been investigated in Enterococcus faecalis, little information is available with respect to its gene regulation. In this study we demonstrate that the presence of exogenous agmatine induces the expression of agu genes in this bacterium. In contrast to the homologous and extensively characterized AgDI system of S. mutants, the aguBDAC operon in E. faecalis is not induced in response to low pH. In spite of this, agmatine catabolism in this bacterium contributes by neutralizing the external medium while enhancing bacterial growth. Our results indicate that carbon catabolic repression (CCR) operates on the AgDI system via a mechanism that involves interaction of CcpA and P-Ser-HPr with a cre site found in an unusual position considering the aguB promoter (55 nt upstream the +1 position). In addition, we found that components of the mannose phosphotransferase (PTSMan) system also contributed to CCR in E. faecalis since a complete relief of the PTS-sugars repressive effect was observed only in a PTSMan and CcpA double defective strain. Our gene context analysis revealed that aguR is present in oral and gastrointestinal microorganisms. Thus, regulation of the aguBDAC operon in E. faecalis seems to have evolved to obtain energy and resist low pH conditions in order to persist and colonize gastrointestinal niches. PMID:24155893

  12. Sewage sludge pretreatment and disposal. (Latest citations from the NTIS bibliographic database). Published Search

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-06-01

    The bibliography contains citations concerning techniques and equipment used in the pretreatment and disposal of sewage sludges. Citations discuss sludge digestion, dewatering, disinfection, stabilization, chlorination, and desulfurization. Topics include pretreatment programs, land disposal, incineration, and waste utilization. Environmental monitoring and protection, federal regulations, and legal aspects are examined. (Contains 50-250 citations and includes a subject term index and title list.)

  13. Silane pre-treatments on copper and aluminium

    International Nuclear Information System (INIS)

    Deflorian, F.; Rossi, S.; Fedrizzi, L.

    2006-01-01

    A large part of aluminium products are coated with an organic layer in order to improve the corrosion resistance. Copper surfaces are also sometimes protected with an organic coating to improve the durability or the aesthetic properties. Examples of industrial applications are household appliances and heat exchanger components. For these applications it is not rare to have the industrial need to treat at the same time components made of aluminium and copper. In order to extend the service life of the organic coated copper a specific surface pre-treatment is often required. Nevertheless, probably because of the limited market of this application, no specific pre-treatments for copper are industrially developed, with the exception of cleaning procedures, but simply extensions of existing pre-treatments optimised for other metals (aluminium, zinc) are used. The application of silane pre-treatments as adhesion promoters for organic coated metals is remarkably increasing in the last decade, because silanes offer very good performance together with high environmental compatibility. The idea is therefore to try to develop a specific silane based pre-treatment for copper. The starting point is the existing silane products for aluminium, optimising the composition and the application conditions (concentration, temperature, pH of the bath, etc.) in order to develop a high performance copper alloy pre-treatment increasing the protective properties and the adhesion of a successively applied organic coating. Moreover these pre-treatments could be used for aluminium alloys too and therefore could be suggested for multi-metals components. The deposits were analysed using FTIR spectroscopy and optical and electron microscopic observations. A careful electrochemical characterisation, mainly by electrochemical impedance spectroscopy measurements (EIS) was carried out to highlight the presence of silane and to evaluate the performance of the different deposits. In order to study an

  14. Processes for pretreating lignocellulosic biomass: A review

    Energy Technology Data Exchange (ETDEWEB)

    McMillan, J.D.

    1992-11-01

    This paper reviews existing and proposed pretreatment processes for biomass. The focus is on the mechanisms by which the various pretreatments act and the influence of biomass structure and composition on the efficacy of particular pretreatment techniques. This analysis is used to identify pretreatment technologies and issues that warrant further research.

  15. 40 CFR 425.25 - Pretreatment standards for existing sources (PSES).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Pretreatment standards for existing sources (PSES). 425.25 Section 425.25 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS LEATHER TANNING AND FINISHING POINT SOURCE CATEGORY Hair Save, Chrome Tan...

  16. 40 CFR 425.75 - Pretreatment standards for existing sources (PSES).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Pretreatment standards for existing sources (PSES). 425.75 Section 425.75 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS LEATHER TANNING AND FINISHING POINT SOURCE CATEGORY Shearling Subcategory...

  17. 40 CFR 425.46 - Pretreatment standards for new sources (PSNS).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Pretreatment standards for new sources (PSNS). 425.46 Section 425.46 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS LEATHER TANNING AND FINISHING POINT SOURCE CATEGORY Retan-Wet Finish...

  18. 40 CFR 425.15 - Pretreatment standards for existing sources (PSES).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Pretreatment standards for existing sources (PSES). 425.15 Section 425.15 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS LEATHER TANNING AND FINISHING POINT SOURCE CATEGORY Hair Pulp, Chrome Tan...

  19. 40 CFR 425.66 - Pretreatment standards for new sources (PSNS).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Pretreatment standards for new sources (PSNS). 425.66 Section 425.66 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS LEATHER TANNING AND FINISHING POINT SOURCE CATEGORY Through-the-Blue...

  20. 40 CFR 425.95 - Pretreatment standards for existing sources (PSES).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Pretreatment standards for existing sources (PSES). 425.95 Section 425.95 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS LEATHER TANNING AND FINISHING POINT SOURCE CATEGORY Retan-Wet Finish...

  1. 40 CFR 425.86 - Pretreatment standards for new sources (PSNS).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Pretreatment standards for new sources (PSNS). 425.86 Section 425.86 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS LEATHER TANNING AND FINISHING POINT SOURCE CATEGORY Pigskin Subcategory...

  2. 40 CFR 425.65 - Pretreatment standards for existing sources (PSES).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Pretreatment standards for existing sources (PSES). 425.65 Section 425.65 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS LEATHER TANNING AND FINISHING POINT SOURCE CATEGORY Through-the-Blue...

  3. 40 CFR 425.96 - Pretreatment standards for new sources (PSNS).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Pretreatment standards for new sources (PSNS). 425.96 Section 425.96 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS LEATHER TANNING AND FINISHING POINT SOURCE CATEGORY Retan-Wet Finish...

  4. 40 CFR 425.85 - Pretreatment standards for existing sources (PSES).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Pretreatment standards for existing sources (PSES). 425.85 Section 425.85 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS LEATHER TANNING AND FINISHING POINT SOURCE CATEGORY Pigskin Subcategory...

  5. 40 CFR 425.16 - Pretreatment standards for new sources (PSNS).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Pretreatment standards for new sources (PSNS). 425.16 Section 425.16 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS LEATHER TANNING AND FINISHING POINT SOURCE CATEGORY Hair Pulp, Chrome Tan...

  6. 40 CFR 425.55 - Pretreatment standards for existing sources (PSES).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Pretreatment standards for existing sources (PSES). 425.55 Section 425.55 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS LEATHER TANNING AND FINISHING POINT SOURCE CATEGORY No Beamhouse...

  7. 40 CFR 425.26 - Pretreatment standards for new sources (PSNS)

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Pretreatment standards for new sources (PSNS) 425.26 Section 425.26 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS LEATHER TANNING AND FINISHING POINT SOURCE CATEGORY Hair Save, Chrome Tan...

  8. 40 CFR 425.36 - Pretreatment standards for new sources (PSNS).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Pretreatment standards for new sources (PSNS). 425.36 Section 425.36 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS LEATHER TANNING AND FINISHING POINT SOURCE CATEGORY Hair Save or Pulp...

  9. 40 CFR 425.76 - Pretreatment standards for new sources (PSNS).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Pretreatment standards for new sources (PSNS). 425.76 Section 425.76 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS LEATHER TANNING AND FINISHING POINT SOURCE CATEGORY Shearling Subcategory...

  10. 40 CFR 425.56 - Pretreatment standards for new sources (PSNS).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Pretreatment standards for new sources (PSNS). 425.56 Section 425.56 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS LEATHER TANNING AND FINISHING POINT SOURCE CATEGORY No Beamhouse...

  11. 40 CFR 425.45 - Pretreatment standards for existing sources (PSES).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Pretreatment standards for existing sources (PSES). 425.45 Section 425.45 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS LEATHER TANNING AND FINISHING POINT SOURCE CATEGORY Retan-Wet Finish...

  12. Novel agmatine analogue, γ-guanidinooxypropylamine (GAPA) efficiently inhibits proliferation of Leishmania donovani by depletion of intracellular polyamine levels

    International Nuclear Information System (INIS)

    Singh, Sushma; Jhingran, Anupam; Sharma, Ankur; Simonian, Alina R.; Soininen, Pasi; Vepsalainen, Jouko; Khomutov, Alex R.; Madhubala, Rentala

    2008-01-01

    The efficacy of γ-guanidinooxypropylamine (GAPA), a novel agmatine analogue against protozoan parasite, Leishmaniadonovani was evaluated. Wild-type and ornithine decarboxylase-overexpressors of L. donovani were used to study the effect and mode of action of this inhibitor. GAPA inhibited the growth of both promastigotes and amastigotes. Ornithine decarboxylase (ODC) activity and polyamine levels were markedly lower in cells treated with GAPA and proliferation was rescued by addition of putrescine or spermidine. GAPA inhibited L. donovani recombinant ODC with K i value of ∼60 μM. The ODC-overexpressors showed significant resistance to GAPA. GAPA has pK a 6.71 and at physiological pH the analogue can mimic protonated state of putrescine and can probably use putrescine transport system. Transport of putrescine in wild-type L. donovani promastigotes was inhibited by GAPA. We for the first time report that GAPA is a potential antileishmanial lead compound and it possibly inhibits L. donovani growth by depletion of intracellular polyamine levels

  13. Tank Focus Area pretreatment activities

    International Nuclear Information System (INIS)

    McGinnis, C.P.; Welch, T.D.; Manke, K.L.

    1997-01-01

    Plans call for the high-level wastes to be retrieved from the tanks and immobilized in a stable waste form suitable for long-term isolation. Chemistry and chemical engineering operations are required to retrieve the wastes, to condition the wastes for subsequent steps, and to reduce the costs of the waste management enterprise. Pretreatment includes those processes between retrieval and immobilization, and includes preparation of suitable feed material for immobilization and separations to partition the waste into streams that yield lower life-cycle costs. Some of the technologies being developed by the Tank Focus Area (TFA) to process these wastes are described. These technologies fall roughly into three areas: (1) solid/liquid separation (SLS), (2) sludge pretreatment, and (3) supernate pretreatment

  14. Effects of low dose radiation pretreatment on radiation injuried brain's free radicle

    International Nuclear Information System (INIS)

    Xu Fuqi; Wang Cheng; Xie Hong; Tian Ye

    2006-01-01

    Objective: To investigate the effect of low dose radiation pretreatment on radiation in- juried brain's free radicle to provide some useful data of brain radiation injury protection. Methods: One hundred mGy was selected as the pretreatment does, 25 Gy was selected as the challenge does. Experiment rats were divided into three groups randomly, group one as simple group:the group irradiated without exposing to pre-irradiation; group two as 6 h-group: the group irradiated with LDR pretreatment 6 h before exposing to 25 Gy irradiation; group three as 24 h-group:the group irradiated with LDR pretreatment 24 h before 25 Gy irradiation. The observation was done 6 hour's after irradiation, the effect of LDR pretreatment on increasing activity of the superoxide dismutase(SOD) and the content of malondialdehyde(MDA) after the brain tissue homogenate were detected. Results: Com- pared with the simple group, the group with LDR pretreatment showed increasing of SOD and decreasing of MDA at the 6th hour after 25Gy irradiation. In addition, there was no difference between the 6 h-group and the 24 h-group. Conclusion: LDR pretreatment can increase SOD and decrease MDA in some period. It could infer that the suitable LDR pretreatment could play a protective role in the brain radiation injury. (authors)

  15. Anchor of Ni2+ on the Agmatine Sulfate-Modified Electrodes for the Determination of H2O2 in Food

    Science.gov (United States)

    Yan, Yuhua; Zhang, Zhonghui; Xiao, Mingshu; Zhou, Hualan

    2017-07-01

    A method was developed to conveniently and rapidly determine hydrogen peroxide (H2O2) in food. The glassy carbon electrode (GCE) modified with agmatine sulfate (AS) easily anchoring nickel ion was attached to AS with polyamine structure. As a result, more Ni2+ was obtained and transformed to Ni(OH)2/NiOOH on the AS-GCE, which caused the electrode to own much better electrocatalytic performance on H2O2. Based on these, the content of H2O2 in thin sheet of bean curd sample was detected with standard addition method, by which good results were obtained.

  16. Study on the Mechanism of mTOR-Mediated Autophagy during Electroacupuncture Pretreatment against Cerebral Ischemic Injury

    Directory of Open Access Journals (Sweden)

    Zhou-Quan Wu

    2016-01-01

    Full Text Available This study is aimed at investigating the association between the electroacupuncture (EA pretreatment-induced protective effect against early cerebral ischemic injury and autophagy. EA pretreatment can protect cerebral ischemic and reperfusion injuries, but whether the attenuation of early cerebral ischemic injury by EA pretreatment was associated with autophagy is not yet clear. This study used the middle cerebral artery occlusion model to monitor the process of ischemic injury. For rats in the EA pretreatment group, EA pretreatment was conducted at Baihui acupoint before ischemia for 30 min for 5 consecutive days. The results suggested that EA pretreatment significantly increased the expression of autophagy in the cerebral cortical area on the ischemic side of rats. But the EA pretreatment-induced protective effects on the brain could be reversed by the specific inhibitor 3-methyladenine of autophagy. Additionally, the Pearson correlation analysis indicated that the impact of EA pretreatment on p-mTOR (2481 was negatively correlated with its impact on autophagy. In conclusion, the mechanism of EA pretreatment at Baihui acupoint against cerebral ischemic injury is mainly associated with the upregulation of autophagy expression, and its regulation of autophagy may depend on mTOR-mediated signaling pathways.

  17. Alpha-2 adrenoceptors and imidazoline receptors in cardiomyocytes mediate counterbalancing effect of agmatine on NO synthesis and intracellular calcium handling.

    Science.gov (United States)

    Maltsev, Alexander V; Kokoz, Yuri M; Evdokimovskii, Edward V; Pimenov, Oleg Y; Reyes, Santiago; Alekseev, Alexey E

    2014-03-01

    Evidence suggests that intracellular Ca(2+) levels and contractility of cardiomyocytes can be modulated by targeting receptors other than already identified adrenergic or non-adrenergic sarcolemmal receptors. This study uncovers the presence in myocardial cells of adrenergic α2 (α2-AR) and imidazoline I1 (I1R) receptors. In isolated left ventricular myocytes generating stationary spontaneous Ca(2+) transients in the absence of triggered action potentials, the prototypic agonist of both receptors agmatine can activate corresponding signaling cascades with opposing outcomes on nitric oxide (NO) synthesis and intracellular Ca(2+) handling. Specifically, activation of α2-AR signaling through PI3 kinase and Akt/protein kinase B stimulates NO production and abolishes Ca(2+) transients, while targeting of I1R signaling via phosphatidylcholine-specific phospholipase C (PC-PLC) and protein kinase C (PKC) suppresses NO synthesis and elevates averaged intracellular Ca(2+). We identified that endothelial NO synthase (eNOS) is a major effector for both signaling cascades. According to the established eNOS transitions between active (Akt-dependent) and inactive (PKC-dependent) conformations, we suggest that balance between α2-AR and I1R signaling pathways sets eNOS activity, which by defining operational states of myocellular sarcoplasmic reticulum Ca(2+)-ATPase (SERCA) can adjust Ca(2+) re-uptake and thereby cardiac inotropy. These results indicate that the conventional catalog of cardiomyocyte sarcolemmal receptors should be expanded by the α2-AR and I1R populations, unveiling previously unrecognized targets for endogenous ligands as well as for existing and potential pharmacological agents in cardiovascular medicine. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Attenuation of insulin resistance in rats by agmatine: role of SREBP-1c, mTOR and GLUT-2.

    Science.gov (United States)

    Sharawy, Maha H; El-Awady, Mohammed S; Megahed, Nirmeen; Gameil, Nariman M

    2016-01-01

    Insulin resistance is a serious health condition worldwide; however, its exact mechanisms are still unclear. This study investigates agmatine (AGM; an endogenous metabolite of L-arginine) effects on insulin resistance induced by high fructose diet (HFD) in rats and the possible involved mechanisms. Sprague Dawley rats were fed 60% HFD for 12 weeks, and AGM (10 mg/kg/day, orally) was given from week 9 to 12. AGM significantly reduced HFD-induced elevation in fasting insulin level, homeostasis model assessment of insulin resistance (HOMA-IR) index and liver glycogen content from 3.44-, 3.62- and 2.07- to 2.59-, 2.78- and 1.3-fold, respectively, compared to the control group, while it increased HFD-induced reduction in glucose tolerance. Additionally, AGM significantly decreased HFD-induced elevation in serum triglycerides, low density lipoprotein cholesterol and very low density lipoprotein cholesterol levels from 3.18-, 2.97- and 4.75- to 1.25-, 1.25- and 1.07-fold, respectively, compared to control group. Conversely, AGM had no significant effect on HFD-induced changes in fasting glucose, glycosylated hemoglobin, insulin tolerance and high density lipoprotein cholesterol. Furthermore, AGM significantly reduced HFD-induced elevation in mRNA expression of glucose transporter type-2 (GLUT-2), mammalian target of rapamycin (mTOR) and sterol regulatory element-binding protein-1c (SREBP-1c) without affecting that of peroxisome proliferator-activated receptor-alpha (PPAR-α) in the liver. Additionally, AGM enhanced ACh-induced aortic relaxation and attenuated liver steatosis induced by HFD. In conclusion, AGM may have a therapeutic potential in insulin resistance through suppressing SREBP-1c, mTOR and GLUT-2 in liver.

  19. New insight into the transcarbamylase family: the structure of putrescine transcarbamylase, a key catalyst for fermentative utilization of agmatine.

    Directory of Open Access Journals (Sweden)

    Luis Mariano Polo

    Full Text Available Transcarbamylases reversibly transfer a carbamyl group from carbamylphosphate (CP to an amine. Although aspartate transcarbamylase and ornithine transcarbamylase (OTC are well characterized, little was known about putrescine transcarbamylase (PTC, the enzyme that generates CP for ATP production in the fermentative catabolism of agmatine. We demonstrate that PTC (from Enterococcus faecalis, in addition to using putrescine, can utilize L-ornithine as a poor substrate. Crystal structures at 2.5 Å and 2.0 Å resolutions of PTC bound to its respective bisubstrate analog inhibitors for putrescine and ornithine use, N-(phosphonoacetyl-putrescine and δ-N-(phosphonoacetyl-L-ornithine, shed light on PTC preference for putrescine. Except for a highly prominent C-terminal helix that projects away and embraces an adjacent subunit, PTC closely resembles OTCs, suggesting recent divergence of the two enzymes. Since differences between the respective 230 and SMG loops of PTC and OTC appeared to account for the differential preference of these enzymes for putrescine and ornithine, we engineered the 230-loop of PTC to make it to resemble the SMG loop of OTCs, increasing the activity with ornithine and greatly decreasing the activity with putrescine. We also examined the role of the C-terminal helix that appears a constant and exclusive PTC trait. The enzyme lacking this helix remained active but the PTC trimer stability appeared decreased, since some of the enzyme eluted as monomers from a gel filtration column. In addition, truncated PTC tended to aggregate to hexamers, as shown both chromatographically and by X-ray crystallography. Therefore, the extra C-terminal helix plays a dual role: it stabilizes the PTC trimer and, by shielding helix 1 of an adjacent subunit, it prevents the supratrimeric oligomerizations of obscure significance observed with some OTCs. Guided by the structural data we identify signature traits that permit easy and unambiguous annotation

  20. Agmatine inhibits nuclear factor-κB nuclear translocation in acute spinal cord compression injury rat model

    Directory of Open Access Journals (Sweden)

    Doaa M. Samy

    2016-09-01

    Full Text Available Secondary damage after acute spinal cord compression injury (SCCI exacerbates initial insult. Nuclear factor kappa-B (NF-κB-p65 activation is involved in SCCI deleterious effects. Agmatine (Agm showed neuroprotection against various CNS injuries. However, Agm impact on NF-κB signaling in acute SCCI remains to be investigated. The present study compared the effectiveness of Agm therapy and decompression laminectomy (DL in functional recovery, oxidative stress, inflammatory and apoptotic responses, and modulation of NF-κB activation in acute SCCI rat model. Rats were either sham-operated or subjected to SCCI at T8–9, using 2-Fr. catheter. SCCI rats were randomly treated with DL at T8–9, intraperitoneal Agm (100 mg/kg/day, combined (DL/Agm treatment or saline (n = 16/group. After 28-days of neurological follow-up, spinal cords were either subjected to biochemical measurement of oxidative stress and inflammatory markers or histopathology and immuno-histochemistry for NF-κB-p65 and caspase-3 expression (n = 8/group. Agm was comparable to DL in facilitating neurological functions recovery, reducing inflammation (TNF-α/interleukin-6, and apoptosis. Agm was distinctive in combating oxidative stress. Agm neuroprotective effects were paralleled with inhibition of NF-κB-p65 nuclear translocation. Combined pharmacological and surgical interventions were proved superior in functional recovery. In conclusion, present research suggested a new mechanism for Agm neuroprotection in rats SCCI through inhibition of NF-κB activation.

  1. Delayed brain ischemia tolerance induced by electroacupuncture pretreatment is mediated via MCP-induced protein 1

    Science.gov (United States)

    2013-01-01

    Background Emerging studies have demonstrated that pretreatment with electroacupuncture (EA) induces significant tolerance to focal cerebral ischemia. The present study seeks to determine the involvement of monocyte chemotactic protein-induced protein 1 (MCPIP1), a recently identified novel modulator of inflammatory reactions, in the cerebral neuroprotection conferred by EA pretreatment in the animal model of focal cerebral ischemia and to elucidate the mechanisms of EA pretreatment-induced ischemic brain tolerance. Methods Twenty-four hours after the end of the last EA pretreatment, focal cerebral ischemia was induced by middle cerebral artery occlusion (MCAO) for 90 minutes in male C57BL/6 mice and MCPIP1 knockout mice. Transcription and expression of MCPIP1 gene was monitored by qRT-PCR, Western blot and immunohistochemistry. The neurobehavioral scores, infarction volumes, proinflammatory cytokines and leukocyte infiltration in brain and NF-κB signaling were evaluated after ischemia/reperfusion. Results MCPIP1 protein and mRNA levels significantly increased specifically in mouse brain undergoing EA pretreatment. EA pretreatment significantly attenuated the infarct volume, neurological deficits, upregulation of proinflammatory cytokines and leukocyte infiltration in the brain of wild-type mice after MCAO compared with that of the non-EA group. MCPIP1-deficient mice failed to evoke EA pretreatment-induced tolerance compared with that of the control MCPIP1 knockout group without EA treatment. Furthermore, the activation of NF-κB signaling was significantly reduced in EA-pretreated wild-type mice after MCAO compared to that of the non-EA control group and MCPIP1-deficient mice failed to confer the EA pretreatment-induced inhibition of NF-κB signaling after MCAO. Conclusions Our data demonstrated that MCPIP1 deficiency caused significant lack of EA pretreatment-induced cerebral protective effects after MCAO compared with the control group and that MCPIP1 is

  2. 40 CFR 415.474 - Pretreatment standards for existing sources (PSES).

    Science.gov (United States)

    2010-07-01

    ... sources (PSES). 415.474 Section 415.474 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS INORGANIC CHEMICALS MANUFACTURING POINT SOURCE CATEGORY Nickel Salts Production Subcategory § 415.474 Pretreatment standards for existing sources (PSES). (a) Except as...

  3. Enzymatic hydrolsis of pretreated rice straw

    Energy Technology Data Exchange (ETDEWEB)

    Vlasenko, E.Y.; Shoemaker, S.P. [California Inst. of Food and Agricultural Research, Davis, CA (United States); Ding, H. [California Univ., Davis (Canada). Dept. of Food Science and Technology; Labavitch, J.M. [California Univ., Davis, CA (United States). Dept. of Pomology

    1997-02-01

    California rice straw is being evaluated as a feedstock for production of power and fuel. This paper examines the initial steps in the process: pretreatment of rice straw and enzymatic hydrolysis of the polysaccharides in the pretreated material to soluble sugars. Rice straw was subjected to three distinct pretreatment procedures: acid-catalyzed steam explosion (Swan Biomass Company), acid hydrolysis (U.S. DOE National Renewable Energy Laboratory), and ammonia fiber explosion or AFEX (Texas A and M University). Standard conditions for each pretreatment were used, but none was optimized for rice straw specifically. Six commercial cellulases, products of Genencor International (USA), Novo (Denmark), Iogen (Canada) and Fermtech (Russia) were used for hydrolysis. The Swan- and the acid-pretreatments effectively removed hemicellulose from rice straw, providing high yields of fermentable sugars. The AFEX-pretreatment was distinctly different from other pretreatments in that it did not significantly solubilize hemicellulose. All three pretreatment procedures substantially increased enzymatic digestibility of rice straw. Three commercial Trichoderma-reesei-derived enzyme preparations: Cellulase 100L (Iogen), Spezyme CP (Genencor), and Al (Fermtech), were more active on pretreated rice straw compared than others tested. Conditions for hydrolysis of rice straw using Cellulase 100L were evaluated. The supplementation of this enzyme preparation with cellobiase (Novozyme 188) significantly improved the parameters of hydrolysis for the Swan- and the acid-pretreated materials, but did not affect the hydrolysis of the AFEX-pretreated rice straw. (Author)

  4. Pretreatment Solution for Water Recovery Systems

    Science.gov (United States)

    Muirhead, Dean (Inventor)

    2018-01-01

    Chemical pretreatments are used to produce usable water by treating a water source with a chemical pretreatment that contains a hexavalent chromium and an acid to generate a treated water source, wherein the concentration of sulfate compounds in the acid is negligible, and wherein the treated water source remains substantially free of precipitates after the addition of the chemical pretreatment. Other methods include reducing the pH in urine to be distilled for potable water extraction by pretreating the urine before distillation with a pretreatment solution comprising one or more acid sources selected from a group consisting of phosphoric acid, hydrochloric acid, and nitric acid, wherein the urine remains substantially precipitate free after the addition of the pretreatment solution. Another method described comprises a process for reducing precipitation in urine to be processed for water extraction by mixing the urine with a pretreatment solution comprising hexavalent chromium compound and phosphoric acid.

  5. Method for pretreating lignocellulosic biomass

    Science.gov (United States)

    Kuzhiyil, Najeeb M.; Brown, Robert C.; Dalluge, Dustin Lee

    2015-08-18

    The present invention relates to a method for pretreating lignocellulosic biomass containing alkali and/or alkaline earth metal (AAEM). The method comprises providing a lignocellulosic biomass containing AAEM; determining the amount of the AAEM present in the lignocellulosic biomass; identifying, based on said determining, the amount of a mineral acid sufficient to completely convert the AAEM in the lignocellulosic biomass to thermally-stable, catalytically-inert salts; and treating the lignocellulosic biomass with the identified amount of the mineral acid, wherein the treated lignocellulosic biomass contains thermally-stable, catalytically inert AAEM salts.

  6. Pretreatment Engineering Platform Phase 1 Final Test Report

    International Nuclear Information System (INIS)

    Kurath, Dean E.; Hanson, Brady D.; Minette, Michael J.; Baldwin, David L.; Rapko, Brian M.; Mahoney, Lenna A.; Schonewill, Philip P.; Daniel, Richard C.; Eslinger, Paul W.; Huckaby, James L.; Billing, Justin M.; Sundar, Parameshwaran S.; Josephson, Gary B.; Toth, James J.; Yokuda, Satoru T.; Baer, Ellen B.K.; Barnes, Steven M.; Golovich, Elizabeth C.; Rassat, Scot D.; Brown, Christopher F.; Geeting, John G.H.; Sevigny, Gary J.; Casella, Amanda J.; Bontha, Jagannadha R.; Aaberg, Rosanne L.; Aker, Pamela M.; Guzman-Leong, Consuelo E.; Kimura, Marcia L.; Sundaram, S.K.; Pires, Richard P.; Wells, Beric E.; Bredt, Ofelia P.

    2009-01-01

    Pacific Northwest National Laboratory (PNNL) was tasked by Bechtel National Inc. (BNI) on the River Protection Project, Hanford Tank Waste Treatment and Immobilization Plant (RPP-WTP) project to conduct testing to demonstrate the performance of the WTP Pretreatment Facility (PTF) leaching and ultrafiltration processes at an engineering-scale. In addition to the demonstration, the testing was to address specific technical issues identified in Issue Response Plan for Implementation of External Flowsheet Review Team (EFRT) Recommendations - M12, Undemonstrated Leaching Processes. Testing was conducted in a 1/4.5-scale mock-up of the PTF ultrafiltration system, the Pretreatment Engineering Platform (PEP). Parallel laboratory testing was conducted in various PNNL laboratories to allow direct comparison of process performance at an engineering-scale and a laboratory-scale. This report presents and discusses the results of those tests.

  7. Pretreatment Engineering Platform Phase 1 Final Test Report

    Energy Technology Data Exchange (ETDEWEB)

    Kurath, Dean E.; Hanson, Brady D.; Minette, Michael J.; Baldwin, David L.; Rapko, Brian M.; Mahoney, Lenna A.; Schonewill, Philip P.; Daniel, Richard C.; Eslinger, Paul W.; Huckaby, James L.; Billing, Justin M.; Sundar, Parameshwaran S.; Josephson, Gary B.; Toth, James J.; Yokuda, Satoru T.; Baer, Ellen BK; Barnes, Steven M.; Golovich, Elizabeth C.; Rassat, Scot D.; Brown, Christopher F.; Geeting, John GH; Sevigny, Gary J.; Casella, Amanda J.; Bontha, Jagannadha R.; Aaberg, Rosanne L.; Aker, Pamela M.; Guzman-Leong, Consuelo E.; Kimura, Marcia L.; Sundaram, S. K.; Pires, Richard P.; Wells, Beric E.; Bredt, Ofelia P.

    2009-12-23

    Pacific Northwest National Laboratory (PNNL) was tasked by Bechtel National Inc. (BNI) on the River Protection Project, Hanford Tank Waste Treatment and Immobilization Plant (RPP-WTP) project to conduct testing to demonstrate the performance of the WTP Pretreatment Facility (PTF) leaching and ultrafiltration processes at an engineering-scale. In addition to the demonstration, the testing was to address specific technical issues identified in Issue Response Plan for Implementation of External Flowsheet Review Team (EFRT) Recommendations - M12, Undemonstrated Leaching Processes.( ) Testing was conducted in a 1/4.5-scale mock-up of the PTF ultrafiltration system, the Pretreatment Engineering Platform (PEP). Parallel laboratory testing was conducted in various PNNL laboratories to allow direct comparison of process performance at an engineering-scale and a laboratory-scale. This report presents and discusses the results of those tests.

  8. Flower-Like Nanoparticles of Pt-BiIII Assembled on Agmatine Sulfate Modified Glassy Carbon Electrode and Their Electrocatalysis of H2O2

    Science.gov (United States)

    Xiao, Mingshu; Yan, Yuhua; Feng, Kai; Tian, Yanping; Miao, Yuqing

    2015-04-01

    A new electrochemical technique to detect hydrogen peroxide (H2O2) was developed. The Pt nanoparticles and BiIII were subsequently assembled on agmatine sulfate (AS) modified glassy carbon electrode (GCE) and the prepared GCE-AS-Pt-BiIII was characterized by scanning electron microscopy (SEM) with result showing that the flower-like nanostructure of Pt-BiIII was yielded. Compared with Pt nanoparticles, the flower-like nanostructure of Pt-BiIII greatly enhanced the electrocatalysis of GCE-AS-Pt-BiIII towards H2O2, which is ascribed to more Pt-OH obtained on GCE-AS-Pt-BiIII surface for the presence of BiIII. Based on its high electrocatalysis, GCE-AS-Pt-BiIII was used to determine the content of H2O2 in the sample of sheet bean curd with standard addition method. Meantime, its electrocatalytic activity also was studied.

  9. Effects of agmatine on secretion of interferon tau and catecholamines and expression of genes related to production of polyamines by ovine trophectoderm cells.

    Science.gov (United States)

    Lenis, Yasser Y; Wang, Xiaoqiu; Tang, Wanjin; Wu, Guoyao; Bazer, Fuller W

    2016-10-01

    Embryonic survival requires histotrophic nutrition, including molecules secreted or transported into the uterine lumen by uterine epithelia. L-Arginine (Arg) is a common substrate for synthesis of nitric oxide, ornithine, proline, glutamate, creatinine, urea, polyamines and agmatine. Agmatine (Agm) is a product of arginine decarboxylation and it is a substrate for agmatinase for synthesis of putrescine and other polyamines in the ovine conceptus. Polyamines are essential for conceptus development. Therefore, this study compared effects of Arg and Agm on the behavior of ovine trophectoderm (oTr1) cells cultured in vitro. Arg, but not Agm, increased proliferation and migration of oTr1 cells, but neither Arg nor Agm affected cell adhesion. The total amount of IFNT in culture medium of oTr1 cells was increased by Arg, but Agm increased the IFNT production per oTr1 cell. Arg and Agm plus Arg decreased secretion of dopamine and norepinephrine by oTr1 cells. Agm upregulates expression of mRNAs SLC7A1, agmatinase and OAZ2 while the combination of Arg and Agm decreased expression of mRNAs for ODC1, SLC7A1, OAZ1 and OAZ3 by oTr1 cells. Although Agm does not stimulate proliferation, migration or adhesion of oTr1 cells or their secretion of catecholamines, Agm did increase transcription of SLC7A1, agmatinase and OAZ2 genes which would increase the capacity of oTr1 cells to produce polyamines. Collectively, our findings suggest a role for Arg and Agm in the regulation of transport of basic amino acids (including Arg), polyamine synthesis, and secretion of catecholamines by oTr1 cells.

  10. Corrosion resistance of biomimetic calcium phosphate coatings on magnesium due to varying pretreatment time

    Energy Technology Data Exchange (ETDEWEB)

    Waterman, J., E-mail: jay.waterman@pg.canterbury.ac.nz [Department of Mechanical Engineering, University of Canterbury, Christchurch (New Zealand); Pietak, A. [Department of Anatomy and Structural Biology, University of Otago, Dunedin (New Zealand); Birbilis, N. [Department of Materials Engineering, Monash University (Australia); Woodfield, T. [Department of Mechanical Engineering, University of Canterbury, Christchurch (New Zealand); Department of Orthopaedic Surgery, University of Otago, Christchurch (New Zealand); Dias, G. [Department of Anatomy and Structural Biology, University of Otago, Dunedin (New Zealand); Staiger, M.P., E-mail: mark.staiger@canterbury.ac.nz [Department of Mechanical Engineering, University of Canterbury, Christchurch (New Zealand)

    2011-12-15

    Calcium phosphate coatings were prepared on magnesium substrates via a biomimetic coating process. The effects of a magnesium hydroxide pretreatment on the formation and the ultimate corrosion protection of the coatings were studied. The pretreatment layer was found to affect the amount of defects present in the coatings. Corrosion resistance of the coatings was studied in vitro using two simulated body fluids, 0.8% NaCl and Hanks solution. In NaCl, the resistance to corrosion of all samples decreases with time as corrosion proceeded through cracks and other defects in the coatings. Samples with no pretreatment displayed the highest corrosion resistance as these samples had the fewest defects in the coating. However, in Hanks solution, corrosion resistance increased with time due to additional nucleation of calcium phosphate from the fluid on to the substrate. In this solution, additional pretreatment time was beneficial to the overall corrosion resistance.

  11. Wash water waste pretreatment system

    Science.gov (United States)

    1977-01-01

    Investigations were completed on wash waters based on each candidate personal cleansing agent. Evaluations of coagulants, antifoam agents, and the effect of promising antifoams on the chemical precipitation were included. Based on these evaluations two candidate soaps as well as their companion antifoam agents were selected for further work. Operating parameters included the effect of soap concentration, ferric chloride concentration, duration of mixing, and pore size of depth filters on the degree of soap removal. The effect of pressure on water flow through filter cartridges and on the rate of decline of water flow was also investigated. The culmination of the program was the recommendation of a pretreatment concept based on chemical precipitation followed by pressure filtration.

  12. Biomass Deconstruction and Pretreatment | Bioenergy | NREL

    Science.gov (United States)

    Deconstruction and Pretreatment Biomass Deconstruction and Pretreatment Our mission is to transform -cyclohexane hydrocarbons were produced by noble metal and acid zeoloite catalytic upgrading of biomass-derived by mechanical refining process. The left side shows biomass feedstock (represented by brown spheres

  13. Innovative pretreatment strategies for biogas production.

    Science.gov (United States)

    Patinvoh, Regina J; Osadolor, Osagie A; Chandolias, Konstantinos; Sárvári Horváth, Ilona; Taherzadeh, Mohammad J

    2017-01-01

    Biogas or biomethane is traditionally produced via anaerobic digestion, or recently by thermochemical or a combination of thermochemical and biological processes via syngas (CO and H 2 ) fermentation. However, many of the feedstocks have recalcitrant structure and are difficult to digest (e.g., lignocelluloses or keratins), or they have toxic compounds (such as fruit flavors or high ammonia content), or not digestible at all (e.g., plastics). To overcome these challenges, innovative strategies for enhanced and economically favorable biogas production were proposed in this review. The strategies considered are commonly known physical pretreatment, rapid decompression, autohydrolysis, acid- or alkali pretreatments, solvents (e.g. for lignin or cellulose) pretreatments or leaching, supercritical, oxidative or biological pretreatments, as well as combined gasification and fermentation, integrated biogas production and pretreatment, innovative biogas digester design, co-digestion, and bio-augmentation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Pretreatment of the macroalgae Chaetomorpha linum for the production of bioethanol - Comparison of five pretreatment technologies

    DEFF Research Database (Denmark)

    Schultz-Jensen, Nadja; Thygesen, Anders; Thomsen, Sune Tjalfe

    2013-01-01

    -assisted pretreatment (PAP) and ball milling (BM), to determine effects of the pretreatment methods on the conversion of C. linum into ethanol by simultaneous saccharification and fermentation (SSF). WO and BM showed the highest ethanol yield of 44. g ethanol/100. g glucan, which was close to the theoretical ethanol......A qualified estimate for pretreatment of the macroalgae Chaetomorpha linum for ethanol production was given, based on the experience of pretreatment of land-based biomass. C. linum was subjected to hydrothermal pretreatment (HTT), wet oxidation (WO), steam explosion (STEX), plasma...... yield of 57. g ethanol/100. g glucan. A 64% higher ethanol yield, based on raw material, was reached after pretreatment with WO and BM compared with unpretreated C. linum, however 50% of the biomass was lost during WO. Results indicated that the right combination of pretreatment and marine macroalgae...

  15. Evaluation of in vivo [corrected] biological activity of new agmatine analogs of growth hormone-releasing hormone (GH-RH)

    Science.gov (United States)

    Bokser, L; Zarandi, M; Schally, A V

    1990-01-01

    The effects of agmatine analogs of growth hormone releasing hormone (GH-RH) were compared to GH-RH(1-29)-NH2 after intravenous (iv) and subcutaneous (sc) administration to pentobarbital-anesthetized male rats. After the iv injection, the analogs [desNH2-Tyr1,Ala15,Nle27] GH-RH(1-28)Agm (MZ-2-51); [desNH2-Tyr1,D-Lys12,Ala15,Nle27] GH-RH(1-28)Agm (MZ-2-57); [desNH2-Tyr1,Ala15,D-Lys21,Nle27] GH-RH(1-28)Agm (MZ-2-75) and [desNH2-Tyr1, D-Lys12,21, Ala15, Nle27] GH-RH(1-28)Agm (MZ-2-87) showed a potency equivalent to 4.4, 1.9, 1.07 and 1.03 times that of GH-RH (1-29)-NH2, respectively, at 5 min and 5.6, 1.8, 1.9 and 1.8 times higher, respectively, at 15 min. After sc administration, analogs MZ-2-51, MZ-2-57 and MZ-2-75 showed to be 34.3, 14.3 and 10.5 times more potent than the parent hormone at 15 min and 179.1, 88.9 and 45.0 times more active, respectively, at 30 min. In addition, MZ-2-51 had prolonged GH-releasing activity as compared to the standard. We also compared the activity of MZ-2-51 and MZ-2-57 with their homologous L-Arg and D-Arg analogs [desNH2-Tyr1,Ala15,Nle27] GH-RH(1-29)-NH2 (MZ-2-117), [des-NH2Tyr1,D-Lys12, Ala15, Nle27] GH-RH(1-29)NH2 (MZ-2-123) and [desNH2-Tyr1,D-Lys12,Ala15, Nle27,D-Arg29] GH-RH(1-29)NH2 (MZ-2-135) after intramuscular (im) injection. MZ-2-51 induced a somewhat greater GH release than MZ-2-117 at 15 min, both responses being larger than the controls (p less than 0.01) at 15 and 30 min. MZ-2-57, MZ-2-123 and MZ-2-135 given i.m. were able to stimulate GH release only at 15 minutes (p less than 0.05). Animals injected i.m. with MZ-2-51, but not with MZ-2-117, showed GH levels significantly higher than the control group (p less than 0.05) at 60 min. GH-RH(1-29)NH2 had low activity intramuscularly when tested at a dose of 2.5 micrograms. No toxic effects were observed after the iv administration of 1 mg/kg of Agm GH-RH analogs. These results indicate that our Agm analogs are active iv, sc and im and that the substitutions made in these

  16. Neuroprotective effect of pretreatment with ganoderma lucidum in cerebral ischemia/reperfusion injury in rat hippocampus

    Science.gov (United States)

    Zhang, Wangxin; Zhang, Quiling; Deng, Wen; Li, Yalu; Xing, Guoqing; Shi, Xinjun; Du, Yifeng

    2014-01-01

    Ganoderma lucidum is a traditional Chinese medicine, which has been shown to have both anti-oxidative and anti-inflammatory effects, and noticeably decreases both the infarct area and neuronal apoptosis of the ischemic cortex. This study aimed to investigate the protective effects and mechanisms of pretreatment with ganoderma lucidum (by intragastric administration) in cerebral ischemia/reperfusion injury in rats. Our results showed that pretreatment with ganoderma lucidum for 3 and 7 days reduced neuronal loss in the hippocampus, diminished the content of malondialdehyde in the hippocampus and serum, decreased the levels of tumor necrosis factor-α and interleukin-8 in the hippocampus, and increased the activity of superoxide dismutase in the hippocampus and serum. These results suggest that pretreatment with ganoderma lucidum was protective against cerebral ischemia/reperfusion injury through its anti-oxidative and anti-inflammatory actions. PMID:25317156

  17. Alkaline pretreatment of Mexican pine residues for bioethanol ...

    African Journals Online (AJOL)

    Alkaline pretreatment of Mexican pine residues for bioethanol production. ... Keywords: Lignocellulosic biomass, alkaline pretreatment, enzymatic hydrolysis, fermentable sugars, fermentation. African Journal of Biotechnology Vol. 12(31), pp.

  18. Pretreatment of Lignocellulosic Wastes to Improve Ethanol and Biogas Production: A Review

    Directory of Open Access Journals (Sweden)

    Keikhosro Karimi

    2008-09-01

    Full Text Available Lignocelluloses are often a major or sometimes the sole components of different waste streams from various industries, forestry, agriculture and municipalities. Hydrolysis of these materials is the first step for either digestion to biogas (methane or fermentation to ethanol. However, enzymatic hydrolysis of lignocelluloses with no pretreatment is usually not so effective because of high stability of the materials to enzymatic or bacterial attacks. The present work is dedicated to reviewing the methods that have been studied for pretreatment of lignocellulosic wastes for conversion to ethanol or biogas. Effective parameters in pretreatment of lignocelluloses, such as crystallinity, accessible surface area, and protection by lignin and hemicellulose are described first. Then, several pretreatment methods are discussed and their effects on improvement in ethanol and/or biogas production are described. They include milling, irradiation, microwave, steam explosion, ammonia fiber explosion (AFEX, supercritical CO2 and its explosion, alkaline hydrolysis, liquid hot-water pretreatment, organosolv processes, wet oxidation, ozonolysis, dilute- and concentrated-acid hydrolyses, and biological pretreatments.

  19. Benefits of hyperbaric oxygen pretreatment for decompression sickness in Bama pigs.

    Science.gov (United States)

    Qing, Long; Yi, Hong-Jie; Wang, Ye-Wei; Zhou, Quan; Ariyadewa, Dinesh K; Xu, Wei-Gang

    2018-03-07

    Decompression sickness (DCS) occurs when ambient pressure is severely reduced during diving and aviation. Hyperbaric oxygen (HBO) pretreatment has been shown to exert beneficial effects on DCS in rats via heat-shock proteins (HSPs). We hypothesized that HBO pretreatment will also reduce DCS via HSPs in swine models. In the first part of our investigation, six swine were subjected to a session of HBO treatment. HSP32, 60, 70 and 90 were detected, before and at 6, 12, 18, 24 and 30 h following exposure in lymphocytes. In the second part of our investigation, another 10 swine were randomly assigned into two groups (five per group). All swine were subjected to two simulated air dives in a hyperbaric chamber with an interval of 7 days. Eighteen hours before each dive, the swine were pretreated with HBO or air: the first group received air pretreatment prior to the first dive and HBO pretreatment prior to the second; the second group were pretreated with HBO first and then air. Bubble loads, skin lesions, inflammation and endothelial markers were detected after each dive. In lymphocytes, all HSPs increased significantly ( P <0.05), with the greatest expression appearing at 18 h for HSP32 and 70. HBO pretreatment significantly reduced all the determined changes compared with air pretreatment. The results demonstrate that a single exposure to HBO 18 h prior to diving effectively protects against DCS in the swine model, possibly via induction of HSPs. © 2018. Published by The Company of Biologists Ltd.

  20. Protective clothing in the sun | Tamas | Nigerian Journal of Clinical ...

    African Journals Online (AJOL)

    Sun protecting clothing is clothing designed for sun protection and is producted from the fabric rated for its level ultraviolet (UV) protection. Some textiles and fabrics emloyed in the use of sun protective clothing may be pre-treated with UV inhibiting ingredients during manufacture to enhance their UV blocking capacitiy.

  1. Extrusion Pretreatment of Lignocellulosic Biomass: A Review

    Directory of Open Access Journals (Sweden)

    Jun Zheng

    2014-10-01

    Full Text Available Bioconversion of lignocellulosic biomass to bioethanol has shown environmental, economic and energetic advantages in comparison to bioethanol produced from sugar or starch. However, the pretreatment process for increasing the enzymatic accessibility and improving the digestibility of cellulose is hindered by many physical-chemical, structural and compositional factors, which make these materials difficult to be used as feedstocks for ethanol production. A wide range of pretreatment methods has been developed to alter or remove structural and compositional impediments to (enzymatic hydrolysis over the last few decades; however, only a few of them can be used at commercial scale due to economic feasibility. This paper will give an overview of extrusion pretreatment for bioethanol production with a special focus on twin-screw extruders. An economic assessment of this pretreatment is also discussed to determine its feasibility for future industrial cellulosic ethanol plant designs.

  2. Understanding Ionic Liquid Pretreatment of Lignocellulosic Biomasses

    Science.gov (United States)

    Pretreatment of biomass is essential for breaking apart highly ordered and crystalline plant cell walls and loosening the lignin and hemicellulose conjugation to cellulose microfibrills, thereby facilitating enzyme accessibility and adsorption and reducing costs of downstream saccharification proces...

  3. Hydrothermal pretreatments of macroalgal biomass for biorefineries

    DEFF Research Database (Denmark)

    Ruiz, Héctor A.; Rodríguez-Jasso, Rosa M.; Aguedo, Mario

    2015-01-01

    in accordance with the integrated biorefineries. Furthermore, biorefinery concept requires processes that allow efficient utilization of all components of the biomass. The pretreatment step in a biorefinery is often based on hydrothermal principles of high temperatures in aqueous solution. Therefore...

  4. Hydrolysis of alkaline pretreated banana peel

    Science.gov (United States)

    Fatmawati, A.; Gunawan, K. Y.; Hadiwijaya, F. A.

    2017-11-01

    Banana peel is one of food wastes that are rich in carbohydrate. This shows its potential as fermentation substrate including bio-ethanol. This paper presented banana peel alkaline pretreatment and enzymatic hydrolysis. The pretreatment was intended to prepare banana peel in order to increase hydrolysis performance. The alkaline pretreatment used 10, 20, and 30% w/v NaOH solution and was done at 60, 70 and 80°C for 1 hour. The hydrolysis reaction was conducted using two commercial cellulose enzymes. The reaction time was varied for 3, 5, and 7 days. The best condition for pretreatment process was one conducted using 30% NaOH solution and at 80°C. This condition resulted in cellulose content of 90.27% and acid insoluble lignin content of 2.88%. Seven-day hydrolysis time had exhibited the highest reducing sugar concentration, which was7.2869 g/L.

  5. Ultrasonic sludge pretreatment under pressure.

    Science.gov (United States)

    Le, Ngoc Tuan; Julcour-Lebigue, Carine; Delmas, Henri

    2013-09-01

    The objective of this work was to optimize the ultrasound (US) pretreatment of sludge. Three types of sewage sludge were examined: mixed, secondary and secondary after partial methanisation ("digested" sludge). Thereby, several main process parameters were varied separately or simultaneously: stirrer speed, total solid content of sludge (TS), thermal operating conditions (adiabatic vs. isothermal), ultrasonic power input (PUS), specific energy input (ES), and for the first time external pressure. This parametric study was mainly performed for the mixed sludge. Five different TS concentrations of sludge (12-36 g/L) were tested for different values of ES (7000-75,000 kJ/kgTS) and 28 g/L was found as the optimum value according to the solubilized chemical oxygen demand in the liquid phase (SCOD). PUS of 75-150 W was investigated under controlled temperature and the "high power input - short duration" procedure was the most effective at a given ES. The temperature increase in adiabatic US application significantly improved SCOD compared to isothermal conditions. With PUS of 150 W, the effect of external pressure was investigated in the range of 1-16 bar under isothermal and adiabatic conditions for two types of sludge: an optimum pressure of about 2 bar was found regardless of temperature conditions and ES values. Under isothermal conditions, the resulting improvement of sludge disintegration efficacy as compared to atmospheric pressure was by 22-67% and 26-37% for mixed and secondary sludge, respectively. Besides, mean particle diameter (D[4,3]) of the three sludge types decreased respectively from 408, 117, and 110 μm to about 94-97, 37-42, and 36-40 μm regardless of sonication conditions, and the size reduction process was much faster than COD extraction. Copyright © 2013 Elsevier B.V. All rights reserved.

  6. Pretreatment with polyamines alleviate the deleterious effects of diuron in maize leaves.

    Science.gov (United States)

    Durmuş, Nuran; Bekircan, Tuba

    2015-03-01

    The effects of diuron, a photosystem II inhibiting herbicide, on lipid peroxidation, photosynthetic pigments, soluble protein, proline contents and some antioxidant enzymes in maize leaves were studied and protective effects of polyamines against diuron toxicity were investigated. Diuron significantly increased lipid peroxidation, suggesting oxidative damage in the plants and proline content, while it decreased total chlorophyll, carotenoid and soluble protein levels in the leaves during the experiments. Pretreatment with polyamines statistically decreased lipid peroxidation induced by diuron and spermine (SPM) proved to be the most effective polyamine. Also, pretreatment with polyamines significantly prevented the losses of total chlorophyll, carotenoid and soluble protein induced by diuron. On the other hand, pretreatment with polyamines significantly increased proline contents of the leaves in comparison with the leaves treated with diuron. Superoxide dismutase (SOD), guaiacol peroxidase (GPX) and glutathione reductase (GR) activities increased in the leaves treated with diuron while catalase (CAT ) activity decreased. Pretreatment with spermidine (SPD) did not change significantly SOD activity at 24 and 72 hrs of diuron treatment but prevented the increase in SOD activity induced by diuron at 48 h. However, pretreatment with SPD increased GPX activity at 24 h and GR activity at 48 and 72 hrs. CAT activity in the leaves pretreated with SPD was similar to that of the leaves treated with diuron. Pretreatment with SPM prevented the increase in SOD activity induced by diuron at 48 h but significantly increased it at 72 h of diuron treatment. However, pretreatment with SPM did not significantly change GPX and GR activities during the experiments but reversed the decrease in CAT activity induced by diuron at 72 h. Pretreatment with putrescine (PUT) prevented the increase in SOD activity induced by diuron at 48 and 72 hrs while it increased GPX and GR activities at 48

  7. Pretreatment techniques for biofuels and biorefineries

    Energy Technology Data Exchange (ETDEWEB)

    Fang, Zhen (ed.) [Chinese Academy of Sciences, Kunming, YN (China). Xishuangbanna Tropical Botonical Garden

    2013-02-01

    The first book focused on pretreatment techniques for biofuels contributed by the world's leading experts. Extensively covers the different types of biomass, various pretreatment approaches and methods that show the subsequent production of biofuels and chemicals. In addition to traditional pretreatment methods, novel techniques are also introduced and discussed. An accessible reference work for students, researchers, academicians and industrialists in biorefineries. This book includes 19 chapters contributed by the world's leading experts on pretreatment methods for biomass. It extensively covers the different types of biomass (e.g. molasses, sugar beet pulp, cheese whey, sugarcane residues, palm waste, vegetable oil, straws, stalks and wood), various pretreatment approaches (e.g. physical, thermal, chemical, physicochemical and biological) and methods that show the subsequent production of biofuels and chemicals such as sugars, ethanol, extracellular polysaccharides, biodiesel, gas and oil. In addition to traditional methods such as steam, hot-water, hydrothermal, diluted-acid, organosolv, ozonolysis, sulfite, milling, fungal and bacterial, microwave, ultrasonic, plasma, torrefaction, pelletization, gasification (including biogas) and liquefaction pretreatments, it also introduces and discusses novel techniques such as nano and solid catalysts, organic electrolyte solutions and ionic liquids. This book offers a review of state-of-the-art research and provides guidance for the future paths of developing pretreatment techniques of biomass for biofuels, especially in the fields of biotechnology, microbiology, chemistry, materials science and engineering. It intends to provide a systematic introduction of pretreatment techniques. It is an accessible reference work for students, researchers, academicians and industrialists in biorefineries.

  8. The agmatine-containing poly(amidoamine) polymer AGMA1 binds cell surface heparan sulfates and prevents attachment of mucosal human papillomaviruses.

    Science.gov (United States)

    Cagno, Valeria; Donalisio, Manuela; Bugatti, Antonella; Civra, Andrea; Cavalli, Roberta; Ranucci, Elisabetta; Ferruti, Paolo; Rusnati, Marco; Lembo, David

    2015-09-01

    The agmatine-containing poly(amidoamine) polymer AGMA1 was recently shown to inhibit the infectivity of several viruses, including human papillomavirus 16 (HPV-16), that exploit cell surface heparan sulfate proteoglycans (HSPGs) as attachment receptors. The aim of this work was to assess the antiviral activity of AGMA1 and its spectrum of activity against a panel of low-risk and high-risk HPVs and to elucidate its mechanism of action. AGMA1 was found to be a potent inhibitor of mucosal HPV types (i.e., types 16, 31, 45, and 6) in pseudovirus-based neutralization assays. The 50% inhibitory concentration was between 0.34 μg/ml and 0.73 μg/ml, and no evidence of cytotoxicity was observed. AGMA1 interacted with immobilized heparin and with cellular heparan sulfates, exerting its antiviral action by preventing virus attachment to the cell surface. The findings from this study indicate that AGMA1 is a leading candidate compound for further development as an active ingredient of a topical microbicide against HPV and other sexually transmitted viral infections. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  9. Microwave pretreatment of switchgrass for bioethanol production

    Science.gov (United States)

    Keshwani, Deepak Radhakrishin

    Lignocellulosic materials are promising alternative feedstocks for bioethanol production. These materials include agricultural residues, cellulosic waste such as newsprint and office paper, logging residues, and herbaceous and woody crops. However, the recalcitrant nature of lignocellulosic biomass necessitates a pretreatment step to improve the yield of fermentable sugars. The overall goal of this dissertation is to expand the current state of knowledge on microwave-based pretreatment of lignocellulosic biomass. Existing research on bioenergy and value-added applications of switchgrass is reviewed in Chapter 2. Switchgrass is an herbaceous energy crop native to North America and has high biomass productivity, potentially low requirements for agricultural inputs and positive environmental impacts. Based on results from test plots, yields in excess of 20 Mg/ha have been reported. Environmental benefits associated with switchgrass include the potential for carbon sequestration, nutrient recovery from run-off, soil remediation and provision of habitats for grassland birds. Published research on pretreatment of switchgrass reported glucose yields ranging from 70-90% and xylose yields ranging from 70-100% after hydrolysis and ethanol yields ranging from 72-92% after fermentation. Other potential value-added uses of switchgrass include gasification, bio-oil production, newsprint production and fiber reinforcement in thermoplastic composites. Research on microwave-based pretreatment of switchgrass and coastal bermudagrass is presented in Chapter 3. Pretreatments were carried out by immersing the biomass in dilute chemical reagents and exposing the slurry to microwave radiation at 250 watts for residence times ranging from 5 to 20 minutes. Preliminary experiments identified alkalis as suitable chemical reagents for microwave-based pretreatment. An evaluation of different alkalis identified sodium hydroxide as the most effective alkali reagent. Under optimum pretreatment

  10. Enzymatic hydrolysis of pretreated soybean straw

    International Nuclear Information System (INIS)

    Xu Zhong; Wang Qunhui; Jiang Zhaohua; Yang Xuexin; Ji Yongzhen

    2007-01-01

    In order to produce lactic acid, from agricultural residues such as soybean straw, which is a raw material for biodegradable plastic production, it is necessary to decompose the soybean straw into soluble sugars. Enzymatic hydrolysis is one of the methods in common use, while pretreatment is the effective way to increase the hydrolysis rate. The optimal conditions of pretreatment using ammonia and enzymatic hydrolysis of soybean straw were determined. Compared with the untreated straw, cellulose in straw pretreated by ammonia liquor (10%) soaking for 24 h at room temperature increased 70.27%, whereas hemicellulose and lignin in pretreated straw decreased to 41.45% and 30.16%, respectively. The results of infrared spectra (IR), scanning electron microscope (SEM) and X-ray diffraction (XRD) analysis also showed that the structure and the surface of the straw were changed through pretreatment that is in favor of the following enzymatic hydrolysis. maximum enzymatic hydrolysis rate of 51.22% was achieved at a substrate concentration of 5% (w/v) at 50 deg. C and pH 4.8 using cellulase (50 fpu/g of substrate) for 36 h

  11. Temperature Modelling of the Biomass Pretreatment Process

    DEFF Research Database (Denmark)

    Prunescu, Remus Mihail; Blanke, Mogens; Jensen, Jakob M.

    2012-01-01

    In a second generation biorefinery, the biomass pretreatment stage has an important contribution to the efficiency of the downstream processing units involved in biofuel production. Most of the pretreatment process occurs in a large pressurized thermal reactor that presents an irregular temperature...... that captures the environmental temperature differences inside the reactor using distributed parameters. A Kalman filter is then added to account for any missing dynamics and the overall model is embedded into a temperature soft sensor. The operator of the plant will be able to observe the temperature in any...

  12. Effect of HCl pre-treatment on corrosion resistance of cerium-based conversion coatings on magnesium and magnesium alloys

    International Nuclear Information System (INIS)

    Brunelli, Katya; Dabala, Manuele; Calliari, Irene; Magrini, Maurizio

    2005-01-01

    The corrosion protection afforded by a cerium conversion coating, formed by immersion in a solution containing rare earth salt and hydrogen peroxide, on pure magnesium and two magnesium alloys, AZ91 and AM50, has been studied. The effect of HCl pre-treatments on the morphology and on the corrosion resistance of the cerium conversion layer was investigated. A thicker and more homogeneous distribution of the conversion coating was obtained when the sample surface was pre-treated with acid. Higher amounts of cerium on the surface of the pre-treated samples were detected. The cerium conversion coating increased the corrosion resistance of the alloys because it ennobled the corrosion potential and decreased both the anodic and cathodic current. The acid pre-treatment further increased the corrosion resistance of the coated alloys. After five days of immersion in chloride environment the untreated samples showed localized corrosion while the chemical conversion coated samples appeared unaffected

  13. Effect of Mucuna pruriens Seed Extract Pretreatment on the Responses of Spontaneously Beating Rat Atria and Aortic Ring to Naja sputatrix (Javan Spitting Cobra) Venom

    Science.gov (United States)

    Fung, Shin Yee; Tan, Nget Hong; Sim, Si Mui; Aguiyi, John C.

    2012-01-01

    Mucuna pruriens Linn. (velvet bean) has been used by native Nigerians as a prophylactic for snakebite. Rats pretreated with M. pruriens seed extract (MPE) have been shown to protect against the lethal and cardiovascular depressant effects of Naja sputatrix (Javan spitting cobra) venoms, and the protective effect involved immunological neutralization of the venom toxins. To investigate further the mechanism of the protective effect of MPE pretreatment against cobra venom toxicity, the actions of Naja sputatrix venom on spontaneously beating rat atria and aortic rings isolated from both MPE pretreated and untreated rats were studied. Our results showed that the MPE pretreatment conferred protection against cobra venom-induced depression of atrial contractility and atrial rate in the isolated atrial preparations, but it had no effect on the venom-induced contractile response of aortic ring preparation. These observations suggested that the protective effect of MPE pretreatment against cobra venom toxicity involves a direct protective action of MPE on the heart function, in addition to the known immunological neutralization mechanism, and that the protective effect does not involve action on blood vessel contraction. The results also suggest that M. pruriens seed may contain novel cardioprotective agent with potential therapeutic value. PMID:21785646

  14. Effect of Mucuna pruriens Seed Extract Pretreatment on the Responses of Spontaneously Beating Rat Atria and Aortic Ring to Naja sputatrix (Javan Spitting Cobra Venom

    Directory of Open Access Journals (Sweden)

    Shin Yee Fung

    2012-01-01

    Full Text Available Mucuna pruriens Linn. (velvet bean has been used by native Nigerians as a prophylactic for snakebite. Rats pretreated with M. pruriens seed extract (MPE have been shown to protect against the lethal and cardiovascular depressant effects of Naja sputatrix (Javan spitting cobra venoms, and the protective effect involved immunological neutralization of the venom toxins. To investigate further the mechanism of the protective effect of MPE pretreatment against cobra venom toxicity, the actions of Naja sputatrix venom on spontaneously beating rat atria and aortic rings isolated from both MPE pretreated and untreated rats were studied. Our results showed that the MPE pretreatment conferred protection against cobra venom-induced depression of atrial contractility and atrial rate in the isolated atrial preparations, but it had no effect on the venom-induced contractile response of aortic ring preparation. These observations suggested that the protective effect of MPE pretreatment against cobra venom toxicity involves a direct protective action of MPE on the heart function, in addition to the known immunological neutralization mechanism, and that the protective effect does not involve action on blood vessel contraction. The results also suggest that M. pruriens seed may contain novel cardioprotective agent with potential therapeutic value.

  15. Technical Basis of Scaling Relationships for the Pretreatment Engineering Platform

    Energy Technology Data Exchange (ETDEWEB)

    Kuhn, William L.; Arm, Stuart T.; Huckaby, James L.; Kurath, Dean E.; Rassat, Scot D.

    2008-07-15

    Pacific Northwest National Laboratory has been tasked by Bechtel National Inc. (BNI) on the River Protection Project-Waste Treatment Plant (RPP-WTP) project to perform research and development activities. The Pretreatment Engineering Platform (PEP) is being designed and constructed as part of a plan to respond to an issue raised by the WTP External Flowsheet Review Team (EFRT) entitled “Undemonstrated Leaching Processes” and numbered M12. The PEP replicates the WTP leaching process using prototypic equipment and control strategies. The approach for scaling PEP performance data to predict WTP performance is critical to the successful resolution of the EFRT issue. This report describes the recommended PEP scaling approach, PEP data interpretation and provides recommendations on test conduct and data requirements.

  16. Technical Basis of Scaling Relationships for the Pretreatment Engineering Platform

    International Nuclear Information System (INIS)

    Kuhn, William L.; Arm, Stuart T.; Huckaby, James L.; Kurath, Dean E.; Rassat, Scot D.

    2008-01-01

    Pacific Northwest National Laboratory has been tasked by Bechtel National Inc. (BNI) on the River Protection Project-Waste Treatment Plant (RPP-WTP) project to perform research and development activities. The Pretreatment Engineering Platform (PEP) is being designed and constructed as part of a plan to respond to an issue raised by the WTP External Flowsheet Review Team (EFRT) entitled 'Undemonstrated Leaching Processes' and numbered M12. The PEP replicates the WTP leaching process using prototypic equipment and control strategies. The approach for scaling PEP performance data to predict WTP performance is critical to the successful resolution of the EFRT issue. This report describes the recommended PEP scaling approach, PEP data interpretation and provides recommendations on test conduct and data requirements

  17. Simulation of the ozone pretreatment of wheat straw.

    Science.gov (United States)

    Bhattarai, Sujala; Bottenus, Danny; Ivory, Cornelius F; Gao, Allan Haiming; Bule, Mahesh; Garcia-Perez, Manuel; Chen, Shulin

    2015-11-01

    Wheat straw is a potential feedstock in biorefinery for sugar production. However, the cellulose, which is the major source of sugar, is protected by lignin. Ozonolysis deconstructs the lignin and makes cellulose accessible to enzymatic digestion. In this study, the change in lignin concentration with different ozonolysis times (0, 1, 2, 3, 5, 7, 10, 15, 20, 30, 60min) was fit to two different kinetic models: one using the model developed by Garcia-Cubero et al. (2012) and another including an outer mass transfer barrier or "cuticle" region where ozone mass transport is reduced in proportion to the mass of unreacted insoluble lignin in the cuticle. The kinetic parameters of two mathematical models for predicting the soluble and insoluble lignin at different pretreatment time were determined. The results showed that parameters derived from the cuticle-based model provided a better fit to experimental results compared to a model without a cuticle layer. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Antibacterial effect of surface pretreatment techniques against ...

    African Journals Online (AJOL)

    Objective: The aim of this study was to evaluate the antibacterial surface pretreatment methods against Streptococcus mutans within the infected dentin surface using a tooth cavity model. Material and Methods: Seventy-two cavities were prepared on caries-free third molars (n = 8). After sterilization, teeth were inoculated ...

  19. Bromine pretreated chitosan for adsorption of lead

    Indian Academy of Sciences (India)

    Pollution by heavy metals like lead (II) is responsible for health hazards and environmental degradation. Adsorption is a prevalent method applied for removal of heavy metal pollutants from water. This study explored adsorption performances of 30% bromine pretreated chitosan for lead (II) abatement from water. Bromine ...

  20. Effective pretreatment of coal for briquetting

    Energy Technology Data Exchange (ETDEWEB)

    Sunami, Y; Nishioka, K; Sugimoto, Y

    1980-01-01

    The pretreatment of coal for briquetting is considered in an attempt to improve the quality of the briquets produced. Crushing of coal to obtain a size distribution suitable for close packing was found to be effective in improving coking properties while drying of coal was found to be effective in increasing briquet density. (In Japanese)

  1. Biomass Deconstruction and Pretreatment Publications | Bioenergy | NREL

    Science.gov (United States)

    Analysis, ACS Sustainable Chemistry & Engineering Eight black-and-white micrograph images of corn Hydrocarbons via Aqueous Phase Hydrodeoxygenation, Green Chemistry Image of a diagram with a curved line Chemistry & Engineering Image of a diagram corn stover pretreatment showing arrows pointing from "

  2. Pretreatment of lignocellulosic biomass using Fenton chemistry

    Science.gov (United States)

    Pretreatment is a necessary step in “biomass to biofuel conversion” due to the recalcitrant nature of lignocellulosic biomass. White-rot fungi utilize peroxidases and hydrogen peroxide (in vivo Fenton chemistry) to degrade lignin. In an attempt to mimic this process, solution phase Fenton chemistry ...

  3. Glass transition temperature of dried lens tissue pretreated with trehalose, maltose, or cyclic tetrasaccharide.

    Science.gov (United States)

    Kawata, Tetsuhiro; Matsuo, Toshihiko; Uchida, Tetsuya

    2014-01-01

    Glass transition temperature is a main indicator for amorphous polymers and biological macromolecules as materials, and would be a key for understanding the role of trehalose in protecting proteins and cells against desiccation. In this study, we measured the glass transition temperature by differential scanning calorimetry of dried lens tissues as a model of a whole biological tissue to know the effect of pretreatment by trehalose and other sugars. Isolated porcine lenses were incubated with saline, 100 or 1000 mM concentration of trehalose, maltose, or cyclic tetrasaccharide dissolved in saline at room temperature for 150 minutes. The solutions were removed and all samples were dried at room temperature in a desiccator until no weight change. The dried tissues were ground into powder and placed in a measuring pan for differential scanning calorimetry. The glass transition temperature of the dried lens tissues, as a mean and standard deviation, was 63.0 ± 6.4°C (n = 3) with saline pretreatment; 53.0 ± 0.8°C and 56.3 ± 2.7°C (n = 3), respectively, with 100 and 1000 mM trehalose pretreatment; 56.0 ± 1.6°C and 55.8 ± 1.1°C (n = 3), respectively, with 100 and 1000 mM maltose pretreatment; 60.0 ± 8.8°C and 59.2 ± 6.3°C (n = 3), respectively, with 100 and 1000 mM cyclic tetrasaccharide pretreatment. The glass transition temperature appeared lower, although not significantly, with trehalose and maltose pretreatments than with saline and cyclic tetrasaccharide pretreatments (P > 0.05, Kruskal-Wallis test). The glass transition temperature of the dried lens tissues with trehalose pretreatment appeared more noticeable on the thermogram, compared with other pretreatments. The glass transition temperature was measured for the first time in the dried lens tissues as an example of a whole biological tissue and might provide a basis for tissue preservation in the dried condition.

  4. NON-POLLUTING METAL SURFACE FINISHING PRETREATMENT AND PRETREATMENT/CONVERSION COATING

    Science.gov (United States)

    Picklex, a proprietary formulation, is an alterantive to conventional metal surface pretreatments and is claimed not to produce waste or lower production or lower performance. A laboratory program was designed to evaluate Picklex in common, large scale, polluting surface finishin...

  5. Pretreatment of Reed by Wet Oxidation and Subsequent Utilization of the Pretreated Fibers for Ethanol Production

    DEFF Research Database (Denmark)

    Szijarto, Nora; Kádár, Zsófia; Varga, Eniko

    2009-01-01

    lignocelluloses usually do. In the present study, wet oxidation was investigated as the pretreatment method to enhance the enzymatic digestibility of reed cellulose to soluble sugars and thus improve the convertibility of reed to ethanol. The most effective treatment increased the digestibility of reed cellulose...... of cellulose to glucose was 82.4%. Simultaneous saccharification and fermentation of pretreated solids resulted in a final ethanol concentration as high as 8.7 g/L, yielding 73% of the theoretical....

  6. 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.

  7. 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.

  8. The impacts of pretreatment on the fermentability of pretreated lignocellulosic biomass: a comparative evaluation between ammonia fiber expansion and dilute acid pretreatment

    Directory of Open Access Journals (Sweden)

    Dale Bruce E

    2009-12-01

    Full Text Available Abstract Background Pretreatment chemistry is of central importance due to its impacts on cellulosic biomass processing and biofuels conversion. Ammonia fiber expansion (AFEX and dilute acid are two promising pretreatments using alkaline and acidic pH that have distinctive differences in pretreatment chemistries. Results Comparative evaluation on these two pretreatments reveal that (i AFEX-pretreated corn stover is significantly more fermentable with respect to cell growth and sugar consumption, (ii both pretreatments can achieve more than 80% of total sugar yield in the enzymatic hydrolysis of washed pretreated solids, and (iii while AFEX completely preserves plant carbohydrates, dilute acid pretreatment at 5% solids loading degrades 13% of xylose to byproducts. Conclusion The selection of pretreatment will determine the biomass-processing configuration, requirements for hydrolysate conditioning (if any and fermentation strategy. Through dilute acid pretreatment, the need for hemicellulase in biomass processing is negligible. AFEX-centered cellulosic technology can alleviate fermentation costs through reducing inoculum size and practically eliminating nutrient costs during bioconversion. However, AFEX requires supplemental xylanases as well as cellulase activity. As for long-term sustainability, AFEX has greater potential to diversify products from a cellulosic biorefinery due to lower levels of inhibitor generation and lignin loss.

  9. Anticorrosive behaviour of Cr(VI)-free surface pretreatments applied on magnesium alloys

    OpenAIRE

    Simancas Peco, Joaquín; Fuente, Daniel de la; Chico, Belén; Madueño, L.; Camón, F.; Blanco, M. C.; Morcillo, Manuel

    2013-01-01

    Among the anticorrosive protection technologies for magnesium alloys, the development of paint systems is a pressing need especially for the automotive and aeronautical industries. Conventional technologies are based on the use of Cr(VI) based compounds, both in pretreatments and primers, but for health and environmental reasons these technologies are being abandoned. An added problem in the painting of magnesium alloys is the lack of adhesion and the high reactivity of magnesium substrates, ...

  10. Radiation pretreatment of cellulose for energy production

    Science.gov (United States)

    Dela Rosa, A. M.; Dela Mines, A. S.; Banzon, R. B.; Simbul-Nuguid, Z. F.

    The effect of radiation pretreatment of agricultural cellulosic wastes was investigated through hydrolytic reactions of cellulose. Gamma irradiation significantly increased the acid hydrolysis of rice straw, rice hull and corn husk. The yields of reducing sugar were higher with increasing radiation dose in these materials. The observed radiation effect varied with the cellulosic material but it correlated with neither the cellulose content nor the lignin content. Likewise, the radiation pretreatment accelerated the subsequent enzymatic hydrolysis of rice straw and rice hull by cellulase. The irradiated rice straw appeared to be a better growth medium for the cellulolytic microorganism, Myrothecium verrucaria, than the non-irradiated material. This was attributed to increased digestibility of the cellulose by the microorganism.

  11. Radiation pretreatment of cellulose for energy production

    International Nuclear Information System (INIS)

    Dela Rosa, A.M.; Dela Mines, A.S.; Banzon, R.B.; Simbul-Nuguid, Z.F.

    1983-01-01

    The effect of radiation pretreatment of agricultural cellulosic wastes was investigated through hydrolytic reactions of cellulose. Gamma irradiation significantly increased the acid hydrolysis of rice straw, rice hull and corn husk. The yields of reducing sugar were higher with increasing radiation dose in these materials. The observed radiation effect varied with the cellulose material but it correlated with neither the cellulose content nor the lignin content. Likewise, the radiation pretreatment accelerated the subsequent enzymatic hydrolysis of rice straw and rice hull by cellulase. The irradiated rice straw appeared to be a better growth medium for the cellulolytic microorganism, Myrothecium verrucaria, than the non-irradiated material. This was attributed to increased digestibility of the cellulose by the microorganism. (author)

  12. PRETREATMENT OF LIGNOCELLULOSIC BIOMASS FOR ENZYMATIC HYDROLYSIS

    Directory of Open Access Journals (Sweden)

    Doan Thai Hoa

    2017-11-01

    Full Text Available The cost of raw materials continues to be a limiting factor in the production of bio-ethanol from traditional raw materials, such as sugar and starch. At the same time, there are large amount of agricultural residues as well as industrial wastes that are of low or negative value (due to costs of current effluent disposal methods. Dilute sulfuric acid pretreatment of elephant grass and wood residues for the enzymatic hydrolysis of cellulose has been investigated in this study.    Elephant grass (agricultural residue and sawdust (Pulp and Paper Industry waste with a small particulate size were treated using different dilute sulfuric acid concentrations at a temperature  of 140-170°C within 0.5-3 hours. The appropriate pretreatment conditions give the highest yield of soluble saccharides and total reducing sugars.

  13. Apple's dehydration by the irradiation pretreatment

    International Nuclear Information System (INIS)

    Fu Junjie; Chao Yan; Shen Weiqiao; Wang Jun

    2001-01-01

    "6"0 Co γ-ray irradiation was used as a pre-treatment method to dry the apple. The aim of this study was to discover the effect factor concerning the change of the apple cell structure which would affect the speed of drhydration and the relation between the speed of hot air dehydration and the irradiation dose. The results demonstrated that with the increasing of irradiation dose. The damage of apple's vacuole membrane increased. The positive correlation was shown in slice thickness and dehydration rate, the relation of the irradiation dose and the temperature of hot air was negatively correlated. The optimum of pre-treatment was gained for slice thickness, the irradiation dose and dry temperature of hot air. (authors)

  14. Waste Separations and Pretreatment Workshop report

    International Nuclear Information System (INIS)

    Cruse, J.M.; Harrington, R.A.; Quadrel, M.J.

    1994-01-01

    This document provides the minutes from the Waste Separations and Pretreatment Workshop sponsored by the Underground Storage Tank-Integrated Demonstration in Salt Lake City, Utah, February 3--5, 1993. The Efficient Separations and Processing-Integrated Program and the Hanford Site Tank Waste Remediation System were joint participants. This document provides the detailed minutes, including responses to questions asked, an attendance list, reproductions of the workshop presentations, and a revised chart showing technology development activities

  15. Design Criteria for Process Wastewater Pretreatment Facilities

    Science.gov (United States)

    1988-05-01

    Stripping Column H13 ’Re Purpose: The purpose of this report, is to provide design criteria for pretreatment needs for ’ I. INTRODUCTION ’". discharge of...which a portion of the vessel is filled with packing. Packing materials vary from corrugated steel to bundles of fibers (Langdon et al., 1972) to beds...concentration(s) using Table 20. Wastewater treatability studies should be considered as a process-screening tool for all wastewater streams for

  16. Pretreatment on Corn Stover with Low Concentration of Formic Acid

    DEFF Research Database (Denmark)

    Xu, Jian; Thomsen, Mette Hedegaard; Thomsen, Anne Belinda

    2009-01-01

    the cellulose easily degraded into sugars and further fermented to ethanol. In this work, hydrothermal pretreatment on corn stover at 195 degrees for 15 min with and without lower concentration of formic acid was compared in terms of sugar recoveries and ethanol fermentation. For pretreatment with formic acid...... pretreatment without formic acid. Toxicity tests of liquor parts showed that there were no inhibitions found for both pretreatment conditions. After simultaneous saccharification and fermentation (SSF) of the pretreated corn stover with Baker's yeast, the highest ethanol yield of 76.5% of the theoretical...

  17. Cost comparison for REDC pretreatment project

    International Nuclear Information System (INIS)

    Robinson, S.M.; Homan, F.J.

    1997-06-01

    This analysis has been prepared to support the planned expenditure to provide the Radiochemical Engineering Development Center (REDC) with the capability to pretreat their liquid low-level waste (LLLW) before discharging it to the Oak Ridge National Laboratory (ORNL) LLLW system. Pretreatment will remove most of the radioactivity, particularly the transuranic isotopes and Cs-137 from the waste to be discharged. This will render the supernates that accumulate in the storage tanks low-activity Class B low-level wastes rather than high-activity Class B or Class C wastes. The sludges will be Class C rather than remote-handled transuranic (RH-TRU) wastes. When REDC wastes are commingled with other ORNL LLLW, the present-worth treatment and transport costs are higher by a factor of 1.3 for the no-pretreatment cases. This result is consistent with data from similar studies conducted at other sites. Based on the information presented in this analysis, the recommendation is to proceed with REDC treatment projects

  18. Electrochemical impedance spectroscopic investigation of the role of alkaline pre-treatment in corrosion resistance of a silane coating on magnesium alloy, ZE41

    Energy Technology Data Exchange (ETDEWEB)

    Chakraborty Banerjee, P. [Department of Chemical Engineering, Monash University, Clayton, VIC-3800 (Australia); CAST Cooperative Research Centre, Hawthorn, VIC-3122 (Australia); Singh Raman, R.K., E-mail: raman.singh@eng.monash.edu.a [Department of Chemical Engineering, Monash University, Clayton, VIC-3800 (Australia); Department of Mechanical and Aerospace Engineering, Monash University, Clayton, VIC-3800 (Australia)

    2011-04-15

    The protective performance of the coatings of bis-1,2-(triethoxysilyl) ethane (BTSE) on ZE41 magnesium alloy with different surface pre-treatments were evaluated using potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) in 0.1 M sodium chloride solution. Electrical equivalent circuits were developed based upon hypothetical corrosion mechanisms and simulated to correspond to the experimental data. The morphology and cross section of the alloy subjected to different pre-treatments and coatings were characterized using scanning electron microscope. A specific alkaline pre-treatment of the substrate prior to the coating has been found to improve the corrosion resistance of the alloy.

  19. Electrochemical impedance spectroscopic investigation of the role of alkaline pre-treatment in corrosion resistance of a silane coating on magnesium alloy, ZE41

    International Nuclear Information System (INIS)

    Chakraborty Banerjee, P.; Singh Raman, R.K.

    2011-01-01

    The protective performance of the coatings of bis-1,2-(triethoxysilyl) ethane (BTSE) on ZE41 magnesium alloy with different surface pre-treatments were evaluated using potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) in 0.1 M sodium chloride solution. Electrical equivalent circuits were developed based upon hypothetical corrosion mechanisms and simulated to correspond to the experimental data. The morphology and cross section of the alloy subjected to different pre-treatments and coatings were characterized using scanning electron microscope. A specific alkaline pre-treatment of the substrate prior to the coating has been found to improve the corrosion resistance of the alloy.

  20. The effect of wastewater pretreatment on nanofiltration membrane performance

    Directory of Open Access Journals (Sweden)

    Ali Hashlamon

    2017-03-01

    Full Text Available Membrane fouling is considered a serious obstacle for operation and cost efficiency in wastewater treatment using nanofiltration (NF. However, pretreatment is the most practical way to reduce this prior to NF. In this research, two types of wastewaters were pretreated with different methods prior to NF to examine the effect of pretreatment on membrane fouling in terms of turbidity, chemical oxygen demand (COD and permeate flux. Turbidity and COD were measured to assess solid foulants and organic species in the wastewater, respectively. The first sample was secondary treated sewage, which was pretreated using coagulation-flocculation-sedimentation (CFS only. Steady flux was increased from 24 L/m2h for wastewater without pretreatment to 32.1 L/m2h with pretreatment. COD was also eliminated after CFS/NF, and turbidity was reduced to 0.6 NTU. The second sample was diluted biodiesel wastewater, which was pretreated using a combination of powdered-activated carbon (PAC adsorption and CFS (PAC/CFS. Steady flux was increased from 22.3 L/m2h for wastewater without pretreatment to 28.7 L/m2h with pretreatment; biodiesel wastewater quality also improved. Turbidity was reduced from 12 to 0.6 NTU, and COD was reduced from 526 to 4 mg/L after NF with PAC/CFS pretreatment, while COD was reduced from 526 to 95 mg/L using NF without pretreatment.

  1. Hydrogen–argon plasma pre-treatment for improving the anti-corrosion properties of thin Al2O3 films deposited using atomic layer deposition on steel

    International Nuclear Information System (INIS)

    Härkönen, Emma; Potts, Stephen E.; Kessels, Wilhelmus M.M.; Díaz, Belén; Seyeux, Antoine; Światowska, Jolanta; Maurice, Vincent; Marcus, Philippe; Radnóczi, György; Tóth, Lajos; Kariniemi, Maarit; Niinistö, Jaakko; Ritala, Mikko

    2013-01-01

    The effect of H 2 –Ar plasma pre-treatment prior to thermal atomic layer deposition (ALD) and plasma-enhanced atomic layer deposition (PEALD) of Al 2 O 3 films on steel for corrosion protection was investigated. Time-of-flight secondary ion mass spectrometry and transmission electron microscopy were used to observe the changes in the interface. The electrochemical properties of the samples were studied with polarization measurements, and the coating porosities were calculated from the polarization results for easier comparison of the coatings. Prior to thermal ALD the plasma pre-treatment was observed to reduce the amount of impurities at the interface and coating porosity by 1–3 orders of magnitude. The anti-corrosion properties of the PEALD coatings could also be improved by the pre-treatment. However, exposure of the pre-treatment plasma activated steel surface to oxygen plasma species in PEALD led to facile oxide layer formation in the interface. The oxide layer formed this way was thicker than the native oxide layer and appeared to be detrimental to the protective properties of the coating. The best performance for PEALD Al 2 O 3 coatings was achieved when, after the plasma pre-treatment, the surface was given time to regrow a thin protective interfacial oxide prior to exposure to the oxygen plasma. The different effects that thermal and plasma-enhanced ALD have on the substrate-coating interface were compared. The reactivity of the oxygen precursor was shown to have a significant influence on substrate surface in the early stages of film growth and thereafter also on the overall quality of the protective film. - Highlights: • Influence of H 2 –Ar plasma pre-treatment to ALD coatings on steel was studied. • The pre-treatment modified the coating–substrate interface composition and thickness. • The pre-treatment improved the barrier properties of the coatings

  2. Reducing biomass recalcitrance via mild sodium carbonate pretreatment.

    Science.gov (United States)

    Mirmohamadsadeghi, Safoora; Chen, Zhu; Wan, Caixia

    2016-06-01

    This study examined the effects of mild sodium carbonate (Na2CO3) pretreatment on enzymatic hydrolysis of different feedstocks (i.e., corn stover, Miscanthus, and switchgrass). The results showed that sodium carbonate pretreatment markedly enhanced the sugar yields of the tested biomass feedstocks. The pretreated corn stover, Miscanthus, and switchgrass gave the glucose yields of 95.1%, 62.3%, and 81.3%, respectively, after enzymatic hydrolysis. The above glucose yields of pretreated feedstocks were 2-4 times that of untreated ones. The pretreatment also enhanced the xylose yields, 4 times for corn stover and 20 times for both Miscanthus and switchgrass. Sodium carbonate pretreatment removed 40-59% lignin from the tested feedstocks while preserving most of cellulose (sodium carbonate pretreatment was effective for reducing biomass recalcitrance and subsequently improving the digestibility of lignocellulosic biomass. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. New degradation compounds from lignocellulosic biomass pretreatment: routes for formation of potent oligophenolic enzyme inhibitors

    DEFF Research Database (Denmark)

    Rasmussen, H.; Tanner, David Ackland; Sørensen, H. R.

    2017-01-01

    -condensation reactions involving aldol condensations, 1,4 additions to α,β unsaturated carbonyl compounds, 3-keto acid decarboxylations and oxidations. Furthermore, pentose reactions with phenolic lignin components are suggested. The identification of the central role of xylose in the reaction routes for oligophenolic...... inhibitor formation led to the solution to protect the reactive anomeric center in xylose. It is shown that protection of the anomeric center in in situ generated xylose with ethylene glycol monobutyl ether, during pretreatment of wheat straw, reduces the level of oligophenols by 73%. The results pave...

  4. Influences of mechanical pretreatment on the non-biological treatment of municipal wastewater by forward osmosis.

    Science.gov (United States)

    Hey, Tobias; Zarebska, Agata; Bajraktari, Niada; Vogel, Jörg; Hélix-Nielsen, Claus; la Cour Jansen, Jes; Jönsson, Karin

    2017-09-01

    Municipal wastewater treatment involves mechanical, biological and chemical treatment steps for protecting the environment from adverse effects. The biological treatment step consumes the most energy and can create greenhouse gases. This study investigates municipal wastewater treatment without the biological treatment step, including the effects of different pretreatment configurations, for example, direct membrane filtration before forward osmosis. Forward osmosis was tested using raw wastewater and wastewater subjected to different types of mechanical pretreatment, for example, microsieving and microfiltration permeation, as a potential technology for municipal wastewater treatment. Forward osmosis was performed using Aquaporin Inside™ and Hydration Technologies Inc. (HTI) membranes with NaCl as the draw solution. Both types of forward osmosis membranes were tested in parallel for the different types of pretreated feed and evaluated in terms of water flux and solute rejection, that is, biochemical oxygen demand (BOD 7 ) and total and soluble phosphorus contents. The Aquaporin and HTI membranes achieved a stable water flux with rejection rates of more than 96% for BOD 7 and total and soluble phosphorus, regardless of the type of mechanical pretreated wastewater considered. This result indicates that forward osmosis membranes can tolerate exposure to municipal waste water and that the permeate can fulfil the Swedish discharge limits.

  5. 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

  6. Synthesis and in vitro and in vivo activity of analogs of growth hormone-releasing hormone (GH-RH) with C-terminal agmatine.

    Science.gov (United States)

    Zarandi, M; Csernus, V; Bokser, L; Bajusz, S; Groot, K; Schally, A V

    1990-12-01

    In the search for more active analogs of human growth hormone-releasing hormone (GH-RH), 37 new compounds were synthesized by solid phase methodology, purified, and tested biologically. Most of the analogs contained a sequence of 27 amino acids and N-terminal desaminotyrosine (Dat) and C-terminal agmatine (Agm), which are not amino acids. In addition to Dat in position 1 and Agm in position 29, the majority of the analogs had Ala15 and Nle27 substitutions and one or more additional L- or D-amino acid modifications. [Dat1, Ala15, Nle27]GH-RH(1-28)Agm (MZ-2-51) was the most active analog. Its in vitro GH-releasing potency was 10.5 times higher than that of GH-RH(1-29)NH2 and in the i.v. in vivo assay, MZ-2-51 was 4-5 times more active than the standard. After s.c. administration to rats. MZ-2-51 showed an activity 34 times higher at 15 min and 179 times greater at 30 min than GH-RH(1-29)NH2 and also displayed a prolonged activity. D-Tyr10, D-Lys12, and D-Lys21 homologs of MZ-2-51 also showed enhanced activities. Thus, [Dat1, D-Tyr10, Ala15, Nle27]GH-RH(1-28)Agm (MZ-2-159), [Dat1, D-Lys12, Ala15, Nle27]GH-RH(1-28)AGM (MZ-2-57), and [Dat1, Ala15, D-Lys21, Nle27]GH-RH(1-28)Agm (MZ-2-75) were 4-6 times more active in vitro than GH-RH(1-29)NH2. In vivo, after i.v. administration, analog MZ-2-75 was equipotent and analogs MZ-2-159 and MZ-2-57 about twice as potent as the standard.(ABSTRACT TRUNCATED AT 250 WORDS)

  7. Attenuation of methamphetamine-induced nigrostriatal dopaminergic neurotoxicity in mice by lipopolysaccharide pretreatment.

    Science.gov (United States)

    Lin, Yin Chiu; Kuo, Yu-Min; Liao, Pao-Chi; Cherng, Chianfang G; Su, Su-Wen; Yu, Lung

    2007-04-30

    Immunological activation has been proposed to play a role in methamphetamine-induced dopaminergic terminal damage. In this study, we examined the roles of lipopolysaccharide, a pro-inflammatory and inflammatory factor, treatment in modulating the methamphetamine-induced nigrostriatal dopamine neurotoxicity. Lipopolysaccharide pretreatment did not affect the basal body temperature or methamphetamine-elicited hyperthermia three days later. Such systemic lipopolysaccharide treatment mitigated methamphetamine-induced striatal dopamine and 3,4-dihydroxyphenylacetic acid depletions in a dose-dependent manner. As the most potent dose (1 mg/kg) of lipopolysaccharide was administered two weeks, one day before or after the methamphetamine dosing regimen, methamphetamine-induced striatal dopamine and 3,4-dihydroxyphenylacetic acid depletions remained unaltered. Moreover, systemic lipopolysaccharide pretreatment (1 mg/kg) attenuated local methamphetamine infusion-produced dopamine and 3,4-dihydroxyphenylacetic acid depletions in the striatum, indicating that the protective effect of lipopolysaccharide is less likely due to interrupted peripheral distribution or metabolism of methamphetamine. We concluded a critical time window for systemic lipopolysaccharide pretreatment in exerting effective protection against methamphetamine-induced nigrostriatal dopamine neurotoxicity.

  8. Rheological evaluation of pretreated cladding removal waste

    International Nuclear Information System (INIS)

    McCarthy, D.; Chan, M.K.C.; Lokken, R.O.

    1986-01-01

    Cladding removal waste (CRW) contains concentrations of transuranic (TRU) elements in the 80 to 350 nCi/g range. This waste will require pretreatment before it can be disposed of as glass or grout at Hanford. The CRW will be pretreated with a rare earth strike and solids removal by centrifugation to segregate the TRU fraction from the non-TRU fraction of the waste. The centrifuge centrate will be neutralized with sodium hydroxide. This neutralized cladding removal waste (NCRW) is expected to be suitable for grouting. The TRU solids removed by centrifugation will be vitrified. The goal of the Rheological Evaluation of Pretreated Cladding Removal Waste Program was to evaluate those rheological and transport properties critical to assuring successful handling of the NCRW and TRU solids streams and to demonstrate transfers in a semi-prototypic pumping environment. This goal was achieved by a combination of laboratory and pilot-scale evaluations. The results obtained during these evaluations were correlated with classical rheological models and scaled-up to predict the performance that is likely to occur in the full-scale system. The Program used simulated NCRW and TRU solid slurries. Rockwell Hanford Operations (Rockwell) provided 150 gallons of simulated CRW and 5 gallons of simulated TRU solid slurry. The simulated CRW was neutralized by Pacific Northwest Laboratory (PNL). The physical and rheological properties of the NCRW and TRU solid slurries were evaluated in the laboratory. The properties displayed by NCRW allowed it to be classified as a pseudoplastic or yield-pseudoplastic non-Newtonian fluid. The TRU solids slurry contained very few solids. This slurry exhibited the properties associated with a pseudoplastic non-Newtonian fluid

  9. Surface pretreatments for medical application of adhesion

    Directory of Open Access Journals (Sweden)

    Weber Michael

    2003-09-01

    Full Text Available Abstract Medical implants and prostheses (artificial hips, tendono- and ligament plasties usually are multi-component systems that may be machined from one of three material classes: metals, plastics and ceramics. Typically, the body-sided bonding element is bone. The purpose of this contribution is to describe developments carried out to optimize the techniques , connecting prosthesis to bone, to be joined by an adhesive bone cement at their interface. Although bonding of organic polymers to inorganic or organic surfaces and to bone has a long history, there remains a serious obstacle in realizing long-term high-bonding strengths in the in vivo body environment of ever present high humidity. Therefore, different pretreatments, individually adapted to the actual combination of materials, are needed to assure long term adhesive strength and stability against hydrolysis. This pretreatment for metal alloys may be silica layering; for PE-plastics, a specific plasma activation; and for bone, amphiphilic layering systems such that the hydrophilic properties of bone become better adapted to the hydrophobic properties of the bone cement. Amphiphilic layering systems are related to those developed in dentistry for dentine bonding. Specific pretreatment can significantly increase bond strengths, particularly after long term immersion in water under conditions similar to those in the human body. The bond strength between bone and plastic for example can be increased by a factor approaching 50 (pealing work increasing from 30 N/m to 1500 N/m. This review article summarizes the multi-disciplined subject of adhesion and adhesives, considering the technology involved in the formation and mechanical performance of adhesives joints inside the human body.

  10. Enzymatic Hydrolysis of Alkaline Pretreated Coconut Coir

    Directory of Open Access Journals (Sweden)

    Akbarningrum Fatmawati

    2013-06-01

    Full Text Available The purpose of this research is to study the effect of concentration and temperature on the cellulose and lignin content, and the reducing sugars produced in the enzymatic hydrolysis of coconut coir. In this research, the coconut coir is pretreated using 3%, 7%, and 11% NaOH solution at 60oC, 80oC, and 100oC. The pretreated coir were assayed by measuring the amount of cellulose and lignin and then hydrolysed using Celluclast and Novozyme 188 under various temperature (30oC, 40oC, 50oC and pH (3, 4, 5. The hydrolysis results were assayed for the reducing sugar content. The results showed that the alkaline delignification was effective to reduce lignin and to increase the cellulose content of the coir. The best delignification condition was observed at 11% NaOH solution and 100oC which removed 14,53% of lignin and increased the cellulose content up to 50,23%. The best condition of the enzymatic hydrolysis was obtained at 50oC and pH 4 which produced 7,57 gr/L reducing sugar. © 2013 BCREC UNDIP. All rights reservedReceived: 2nd October 2012; Revised: 31st January 2013; Accepted: 6th February 2013[How to Cite: Fatmawati, A., Agustriyanto, R., Liasari, Y. (2013. Enzymatic Hydrolysis of Alkaline Pre-treated Coconut Coir. Bulletin of Chemical Reaction Engineering & Catalysis, 8 (1: 34-39 (doi:10.9767/bcrec.8.1.4048.34-39[Permalink/DOI: http://dx.doi.org/10.9767/bcrec.8.1.4048.34-39] | View in  |

  11. Energy consumption modeling during dairy sewage pretreatment

    Directory of Open Access Journals (Sweden)

    Dąbrowski Wojciech

    2017-01-01

    Full Text Available The research was conducted in a dairy WWTP located in north-eastern Poland with the average flow of 546 m3d-1 and PE 11500 in 2016. Energy consumption was measured with the help of Lumel 3-phase network parameter transducers installed within the plant. The modeling was conducted based on the quantity and quality of raw sewage, after its screening, averaging and dissolved air flotation. The following parameters were determined: BOD5, COD. N-total and P-total. During the research period. 15 measurement series were carried out. Pollution loads removed in primary treatment varied from 167.0 to 803.5 kgO2d-1 and 1205.9 to 10032 kgO2d-1 for BOD5 and COD respectively. The energy consumption share during dairy pretreatment in relation to the total energy consumption was in the range from 13.8 to 28.5% with the mean value of 18.7% during the research period. Energy consumption indicators relating to removed pollution loads for primary treatment were established with the mean values of 0.74 and 0.83 kWhkg-1d-1 for BOD5 and COD respectively. An attempt was made to determine the influence of raw sewage characteristics and pretreatment efficiency on energy consumption of the object. A model of energy consumption during pretreatment was estimated according to the experimental data obtained in the research period. It was modeled using the linear regression model and principal component analysis.

  12. Pretreatment and enzymatic hydrolysis of lignocellulosic biomass

    Science.gov (United States)

    Corredor, Deisy Y.

    The performance of soybean hulls and forage sorghum as feedstocks for ethanol production was studied. The main goal of this research was to increase fermentable sugars' yield through high-efficiency pretreatment technology. Soybean hulls are a potential feedstock for production of bio-ethanol due to their high carbohydrate content (≈50%) of nearly 37% cellulose. Soybean hulls could be the ideal feedstock for fuel ethanol production, because they are abundant and require no special harvesting and additional transportation costs as they are already in the plant. Dilute acid and modified steam-explosion were used as pretreatment technologies to increase fermentable sugars yields. Effects of reaction time, temperature, acid concentration and type of acid on hydrolysis of hemicellulose in soybean hulls and total sugar yields were studied. Optimum pretreatment parameters and enzymatic hydrolysis conditions for converting soybean hulls into fermentable sugars were identified. The combination of acid (H2SO4, 2% w/v) and steam (140°C, 30 min) efficiently solubilized the hemicellulose, giving a pentose yield of 96%. Sorghum is a tropical grass grown primarily in semiarid and dry parts of the world, especially in areas too dry for corn. The production of sorghum results in about 30 million tons of byproducts mainly composed of cellulose, hemicellulose, and lignin. Forage sorghum such as brown midrib (BMR) sorghum for ethanol production has generated much interest since this trait is characterized genetically by lower lignin concentrations in the plant compared with conventional types. Three varieties of forage sorghum and one variety of regular sorghum were characterized and evaluated as feedstock for fermentable sugar production. Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM) and X-Ray diffraction were used to determine changes in structure and chemical composition of forage sorghum before and after pretreatment and enzymatic hydrolysis

  13. EFFECT OF AQUEOUS PRETREATMENT ON PYROLYSIS CHARACTERISTICS OF NAPIER GRASS

    Directory of Open Access Journals (Sweden)

    ISAH YAKUB MOHAMMED

    2015-11-01

    Full Text Available Effect of non-catalytic aqueous pretretment on pyrolysis characteristics of Napier grass was investigated using thermogravimetric analyser. Increasing pretreatment severity (0.0-2.0 improved pyrolysis process. The residual mass at the end of pyrolysis for the pretreated sample was about 50% less compared to the untreated sample. Kinetics of the process was evaluated using order based model and both pretreated and untreated samples followed first order reaction. The activation energy of the pretreated samples was similar and higher than that of the raw sample which was attributed to faster rate of decomposition due removal of hetromaterials (ash, extractives and some hemicellulose in the pretreatment stage. Finally, this pretreatment method has demonstrated effectiveness for the removal of pyrolysis retardants and will improve the quantity and quality of bio-oil yield.

  14. Impact of pretreatment on colour and texture of watermelon rind

    Science.gov (United States)

    Athmaselvi, K.; Alagusundaram, K.; Kavitha, C.; Arumuganathan, T.

    2012-07-01

    The effect of osmotic dehydration pretreatment on water loss, solid gain, colour and textural change was investigated. Watermelon rind 1 x 1 cm size was immersed in sucrose solution of 40, 50 and 60° Brix after pretreatment with microwave and conventional boiling in water for 1, 3, and 5 min, respectively. Water loss and solid gain increased with the time of cooking and sugar concentration. Microwave pretreated samples showed higher water loss and solid gain. Increase in the time of cooking decreased the brightness of all the samples. Microwave pretreated samples showed higher `b' values than conventionally pretreated ones. There was no significant difference (P≤0.05) in texture profile analysis parameters except for hardness. Hardness decreased with increase in time of cooking and sugar concentration. Second order regression model was developed for water loss and solid gain of microwave and conventional pretreated watermelon rind.

  15. The characteristic changes of betung bamboo (Dendrocalamus asper pretreated by fungal pretreatment

    Directory of Open Access Journals (Sweden)

    Widya Fatriasari

    2014-05-01

    Full Text Available Normal 0 false false false IN X-NONE X-NONE MicrosoftInternetExplorer4 The fungal pretreatment effect on chemical structural and morphological changes of Betung Bamboo was evaluated based on its biomass components after being cultivated by white rot fungi, Trametes versicolor. Betung bamboo powder (15 g was exposed to liquid inoculum of white rot fungi and incubated at 270C for 15, 30 and 45 days. The treated samples were then characterized by FT-IR spectroscopy, X-Ray diffraction and SEM-EDS analyses. Cultivation for 30 days with 5 and 10% loadings retained greater selectivity compared to that of the other treatments. FTIR spectra demonstrated that the fungus affected the decreasing of functional group quantities without changing the functional groups. The decrease in intensity at wave number of 1246 cm-1 (guaiacyl of lignin was greater than that at wave number of 1328 cm-1 (deformation combination of syringyl and xylan after fungal treatment. X-ray analysis showed the pretreated samples had a higher crystallinity than the untreated ones which might be due to the cleavage of amorphous fractions of cellulose. The pretreated samples have more fragile than the untreated ones confirmed by SEM. Crystalline allomorph calculated by XRD analysis showed that fungus pretreatment for 30 days has transformed triclinic structure of cellulose to monoclinic structure.

  16. Microbial Lipid Production from Enzymatic Hydrolysate of Pecan Nutshell Pretreated by Combined Pretreatment.

    Science.gov (United States)

    Qin, Lizhen; Qian, Hanyu; He, Yucai

    2017-12-01

    Biodiesel is a fuel composed of monoalkyl esters of long-chain fatty acids derived from renewable biomass sources. In this study, biomass waste pecan nutshell (PS) was attempted to be converted into microbial oil. For effective utilization of PS, sequential pretreatment with ethylene glycol-H 2 SO 4 -water (78:2:20, wt:wt:wt) at 130 °C for 30 min and aqueous ammonia (25 wt%) at 50 °C for 24 h was used to enhance its enzymatic saccharification. Significant linear correlation was obtained about delignification-saccharification (R 2  = 0.9507). SEM and FTIR results indicated that combination pretreatment could effectively remove lignin and xylan in PS for promoting its enzymatic saccharification. After 72 h, the reducing sugars from the hydrolysis of 50 g/L pretreated PS by combination pretreatment could be obtained at 73.6% yield. Using the recovered PS hydrolysates containing 20 g/L glucose as carbon source, microbial lipids produced from the PS hydrolysates by Rhodococcus opacus ACCC41043. Four fatty acids including palmitic acid (C16:0; 23.1%), palmitoleic acid (C16:1; 22.4%), stearic acid (C18:0; 15.3%), and oleic acid (C18:1; 23.9%) were distributed in total fatty acids. In conclusion, this strategy has potential application in the future.

  17. Slice image pretreatment for cone-beam computed tomography based on adaptive filter

    International Nuclear Information System (INIS)

    Huang Kuidong; Zhang Dinghua; Jin Yanfang

    2009-01-01

    According to the noise properties and the serial slice image characteristics in Cone-Beam Computed Tomography (CBCT) system, a slice image pretreatment for CBCT based on adaptive filter was proposed. The judging criterion for the noise is established firstly. All pixels are classified into two classes: adaptive center weighted modified trimmed mean (ACWMTM) filter is used for the pixels corrupted by Gauss noise and adaptive median (AM) filter is used for the pixels corrupted by impulse noise. In ACWMTM filtering algorithm, the estimated Gauss noise standard deviation in the current slice image with offset window is replaced by the estimated standard deviation in the adjacent slice image to the current with the corresponding window, so the filtering accuracy of the serial images is improved. The pretreatment experiment on CBCT slice images of wax model of hollow turbine blade shows that the method makes a good performance both on eliminating noises and on protecting details. (authors)

  18. FRACTIONAL CRYSTALLIZATION TESTING WITH INTERIM PRETREATMENT SYSTEM FEEDS

    International Nuclear Information System (INIS)

    HERTING DL

    2008-01-01

    The fractional crystallization process was developed as a pretreatment method for saltcake waste retrieved from Hanford single-shell tanks (SST). The process separates the retrieved SST waste into a high-level waste stream containing the bulk of the radionuclides and a low-activity waste stream containing the bulk of the nonradioactive sodium salts. The Interim Pretreatment System project shifted the focus on pretreatment planning from SST waste to double-shell tank waste

  19. Cellulose conversion of corn pericarp without pretreatment.

    Science.gov (United States)

    Kim, Daehwan; Orrego, David; Ximenes, Eduardo A; Ladisch, Michael R

    2017-12-01

    We report enzyme hydrolysis of cellulose in unpretreated pericarp at a cellulase loading of 0.25FPU/g pericarp solids using a phenol tolerant Aspergillus niger pectinase preparation. The overall protein added was 5mg/g and gave 98% cellulose conversion in 72h. However, for double the amount of enzyme from Trichoderma reesei, which is significantly less tolerant to phenols, conversion was only 16%. The key to achieving high conversion without pretreatment is combining phenol inhibition-resistant enzymes (such as from A. niger) with unground pericarp from which release of phenols is minimal. Size reduction of the pericarp, which is typically carried out in a corn-to-ethanol process, where corn is first ground to a fine powder, causes release of highly inhibitory phenols that interfere with cellulase enzyme activity. This work demonstrates hydrolysis without pretreatment of large particulate pericarp is a viable pathway for directly producing cellulose ethanol in corn ethanol plants. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. K basins sludge removal sludge pretreatment system

    International Nuclear Information System (INIS)

    Chang, H.L.

    1997-01-01

    The Spent Nuclear Fuels Program is in the process of planning activities to remove spent nuclear fuel and other materials from the 100-K Basins as a remediation effort for clean closure. The 105 K- East and K-West Basins store spent fuel, sludge, and debris. Sludge has accumulated in the 1 00 K Basins as a result of fuel oxidation and a slight amount of general debris being deposited, by settling, in the basin water. The ultimate intent in removing the sludge and fuel is to eliminate the environmental risk posed by storing fuel at the K Basins. The task for this project is to disposition specific constituents of sludge (metallic fuel) to produce a product stream through a pretreatment process that will meet the requirements, including a final particle size acceptable to the Tank Waste Remediation System (TWRS). The purpose of this task is to develop a preconceptual design package for the K Basin sludge pretreatment system. The process equipment/system is at a preconceptual stage, as shown in sketch ES-SNF-01 , while a more refined process system and material/energy balances are ongoing (all sketches are shown in Appendix C). Thus, the overall process and 0535 associated equipment have been conservatively selected and sized, respectively, to establish the cost basis and equipment layout as shown in sketches ES- SNF-02 through 08

  1. Biologically Pre-Treated Habitation Waste Water as a Sustainable Green Urine Pre-Treat Solution

    Science.gov (United States)

    Jackson, W. Andrew; Thompson, Bret; Sevanthi, Ritesh; Morse, Audra; Meyer, Caitlin; Callahan, Michael

    2017-01-01

    The ability to recover water from urine and flush water is a critical process to allow long term sustainable human habitation in space or bases on the moon or mars. Organic N present as urea or similar compounds can hydrolyze producing free ammonia. This reaction results in an increase in the pH converting ammonium to ammonia which is volatile and not removed by distillation. The increase in pH will also cause precipitation reactions to occur. In order to prevent this, urine on ISS is combined with a pretreat solution. While use of a pretreatment solution has been successful, there are numerous draw backs including: storage and use of highly hazardous solutions, limitations on water recovery (less than 85%), and production of brine with pore dewatering characteristics. We evaluated the use of biologically treated habitation wastewaters (ISS and early planetary base) to replace the current pretreat solution. We evaluated both amended and un-amended bioreactor effluent. For the amended effluent, we evaluated "green" pretreat chemicals including citric acid and citric acid amended with benzoic acid. We used a mock urine/air separator modeled after the urine collection assembly on ISS. The urine/air separator was challenged continually for >6 months. Depending on the test point, the separator was challenged daily with donated urine and flushed with amended or un-amended reactor effluent. We monitored the pH of the urine, flush solution and residual pH in the urine/air separator after each urine event. We also evaluated solids production and biological growth. Our results support the use of both un-amended and amended bioreactor effluent to maintain the operability of the urine /air separator. The ability to use bioreactor effluent could decrease consumable cost, reduce hazards associated with current pre-treat chemicals, allow other membrane based desalination processes to be utilized, and improve brine characteristics.

  2. Whistleblower Protection

    Science.gov (United States)

    The Whistleblower Protection Enhancement Act of 2012 (WPA) and the Whistleblower Protection Act of 1989 Enhanced by the Act of 2012 provides protection rights for Federal employees against retaliation for whistleblowing activities.

  3. 40 CFR 407.74 - Pretreatment standards for existing sources.

    Science.gov (United States)

    2010-07-01

    ...) EFFLUENT GUIDELINES AND STANDARDS CANNED AND PRESERVED FRUITS AND VEGETABLES PROCESSING POINT SOURCE CATEGORY Canned and Preserved Vegetables Subcategory § 407.74 Pretreatment standards for existing sources...

  4. The Effect of Ultrasound Pretreatment on Poplar Wood Dimensional Stability

    Directory of Open Access Journals (Sweden)

    Shu Qiu

    2016-08-01

    Full Text Available Dimensional stability is a key property of wood that significantly affects its applications. The effect of an ultrasound pretreatment on poplar wood (Populous tomentosa dimensional stability was examined. During the pretreatments, wood samples were immersed in distilled water and treated ultrasonically under three different powers and frequencies. The samples were then analyzed by Fourier transform infrared spectroscopy (FTIR and X-ray diffraction (XRD. The chemical transformation of the cell-wall material was studied and then associated with the change of water absorption and the swelling coefficient. The results showed that the water absorption decreased after the ultrasonic pretreatment. The axial and radial swelling coefficients of the pretreated samples decreased, while the tangential swelling coefficients increased. The volumetric swelling coefficient of pretreated specimens fluctuated near 4.48% (the volumetric swelling coefficient of untreated wood. Ultrasonic pretreatment increased the number of hydrophilic groups, such as the hydroxyl, acetyl, and uronic ester groups. Meanwhile, the pretreatment also increased the degree of crystallinity and reduced the available polar groups. These two factors together caused the change of the moisture absorption and the swelling coefficient of the pretreated wood. These conclusions suggest that the ultrasonic pretreatment is a promising method for further chemical modification of wood.

  5. 40 CFR 427.34 - Pretreatment standards for existing sources.

    Science.gov (United States)

    2010-07-01

    ...) EFFLUENT GUIDELINES AND STANDARDS ASBESTOS MANUFACTURING POINT SOURCE CATEGORY Asbestos Paper (Starch Binder) Subcategory § 427.34 Pretreatment standards for existing sources. Any existing source subject to...

  6. 40 CFR 427.44 - Pretreatment standards for existing sources.

    Science.gov (United States)

    2010-07-01

    ...) EFFLUENT GUIDELINES AND STANDARDS ASBESTOS MANUFACTURING POINT SOURCE CATEGORY Asbestos Paper (Elastomeric Binder) Subcategory § 427.44 Pretreatment standards for existing sources. Any existing source subject to...

  7. 40 CFR 417.84 - Pretreatment standards for existing sources.

    Science.gov (United States)

    2010-07-01

    ...) EFFLUENT GUIDELINES AND STANDARDS SOAP AND DETERGENT MANUFACTURING POINT SOURCE CATEGORY Manufacture of Liquid Soaps Subcategory § 417.84 Pretreatment standards for existing sources. Any existing source...

  8. Nonhazardous Urine Pretreatment Method for Future Exploration Systems, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — A nonhazardous urine pretreatment system prototype is proposed that will stabilize urine against biological growth or chemical instabilities without using hazardous...

  9. Nonhazardous Urine Pretreatment Method for Future Exploration Systems, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — A novel urine pretreatment that will prevent biological growth or chemical instabilities in urine without using hazardous chemicals is proposed. Untreated urine...

  10. Feasibility of Hydrothermal Pretreatment on Maize Silage for Bioethanol Production

    DEFF Research Database (Denmark)

    Xu, Jian; Thomsen, Mette Hedegaard; Thomsen, Anne Belinda

    2010-01-01

    The potential of maize silage as a feedstock to produce bioethanol was evaluated in the present study. The hydrothermal pretreatment with five different pretreatment severity factors (PSF) was employed to pretreat the maize silage and compared in terms of sugar recovery, toxic test, and ethanol...... the liquors from the five conditions were not toxic to the Baker’s yeast. Pretreatment under 195°C for 7 min had the similar PSF with that of 185°C for 15 min, and both gave the higher ethanol concentration of 19.92 and 19.98 g/L, respectively. The ethanol concentration from untreated maize silage was only 7...

  11. Radiation protection

    International Nuclear Information System (INIS)

    Koelzer, W.

    1975-01-01

    Physical and radiological terms, quantities, and units. Basic principles of radiation protection (ICRP, IAEA, EURATOM, FRG). Biological effects of ionizing radiation. Objectives of practical radiation protection. (HP) [de

  12. Understanding of alkaline pretreatment parameters for corn stover enzymatic saccharification

    Directory of Open Access Journals (Sweden)

    Chen Ye

    2013-01-01

    Full Text Available Abstract Background Previous research on alkaline pretreatment has mainly focused on optimization of the process parameters to improve substrate digestibility. To achieve satisfactory sugar yield, extremely high chemical loading and enzyme dosages were typically used. Relatively little attention has been paid to reduction of chemical consumption and process waste management, which has proven to be an indispensable component of the bio-refineries. To indicate alkali strength, both alkali concentration in pretreatment solution (g alkali/g pretreatment liquor or g alkali/L pretreatment liquor and alkali loading based on biomass solids (g alkali/g dry biomass have been widely used. The dual approaches make it difficult to compare the chemical consumption in different process scenarios while evaluating the cost effectiveness of this pretreatment technology. The current work addresses these issues through pretreatment of corn stover at various combinations of pretreatment conditions. Enzymatic hydrolysis with different enzyme blends was subsequently performed to identify the effects of pretreatment parameters on substrate digestibility as well as process operational and capital costs. Results The results showed that sodium hydroxide loading is the most dominant variable for enzymatic digestibility. To reach 70% glucan conversion while avoiding extensive degradation of hemicellulose, approximately 0.08 g NaOH/g corn stover was required. It was also concluded that alkali loading based on total solids (g NaOH/g dry biomass governs the pretreatment efficiency. Supplementing cellulase with accessory enzymes such as α-arabinofuranosidase and β-xylosidase significantly improved the conversion of the hemicellulose by 6–17%. Conclusions The current work presents the impact of alkaline pretreatment parameters on the enzymatic hydrolysis of corn stover as well as the process operational and capital investment costs. The high chemical consumption for alkaline

  13. Plasma-Assisted Pretreatment of Wheat Straw

    DEFF Research Database (Denmark)

    Schultz-Jensen, Nadja; Leipold, Frank; Bindslev, Henrik

    2011-01-01

    O3 generated in a plasma at atmospheric pressure and room temperature, fed with dried air (or oxygen-enriched dried air), has been used for the degradation of lignin in wheat straw to optimize the enzymatic hydrolysis and to get more fermentable sugars. A fixed bed reactor was used combined...... with a CO2 detector and an online technique for O3 measurement in the fed and exhaust gas allowing continuous measurement of the consumption of O3. This rendered it possible for us to determine the progress of the pretreatment in real time (online analysis). The process time can be adjusted to produce wheat...... straw with desired lignin content because of the online analysis. The O3 consumption of wheat straw and its polymeric components, i.e., cellulose, hemicellulose, and lignin, as well as a mixture of these, dry as well as with 50% water, were studied. Furthermore, the process parameters dry matter content...

  14. Structural changes of corn stover lignin during acid pretreatment.

    Science.gov (United States)

    Moxley, Geoffrey; Gaspar, Armindo Ribeiro; Higgins, Don; Xu, Hui

    2012-09-01

    In this study, raw corn stover was subjected to dilute acid pretreatments over a range of severities under conditions similar to those identified by the National Renewable Energy Laboratory (NREL) in their techno-economic analysis of biochemical conversion of corn stover to ethanol. The pretreated corn stover then underwent enzymatic hydrolysis with yields above 70 % at moderate enzyme loading conditions. The enzyme exhausted lignin residues were characterized by ³¹P NMR spectroscopy and functional moieties quantified and correlated to enzymatic hydrolysis yields. Results from this study indicated that both xylan solubilization and lignin degradation are important for improving the enzyme accessibility and digestibility of dilute acid pretreated corn stover. At lower pretreatment temperatures, there is a good correlation between xylan solubilization and cellulose accessibility. At higher pretreatment temperatures, lignin degradation correlated better with cellulose accessibility, represented by the increase in phenolic groups. During acid pretreatment, the ratio of syringyl/guaiacyl functional groups also gradually changed from less than 1 to greater than 1 with the increase in pretreatment temperature. This implies that more syringyl units are released from lignin depolymerization of aryl ether linkages than guaiacyl units. The condensed phenolic units are also correlated with the increase in pretreatment temperature up to 180 °C, beyond which point condensation reactions may overtake the hydrolysis of aryl ether linkages as the dominant reactions of lignin, thus leading to decreased cellulose accessibility.

  15. Pretreatment of Oil Palm Frond (OPF) with Ionic Liquid

    Science.gov (United States)

    Azmi, I. S.; Azizan, A.; Salleh, R. Mohd

    2018-05-01

    Pretreatment is the key to unlock the recalcitrance of lignocellulose for cellulosic biofuel production. Increasing attention has been drawn to ionic liquids (ILs) for pretreatment of lignocellulosic biomass because this approach was considered as a green engineering method over other conventional methods. In this work, Oil palm frond (OPF) was pretreated by using the ionic liquid 1-ethyl-3-methylimidazolium acetate [EMIM] Ac at the temperature of 99˚C for 3 hours. The characterization of the untreated and pretreated OPF was conducted by using different techniques which are Fourier Transform Infrared Spectroscopy (FTIR), X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). The pretreatment of OPF with [EMIM] Ac was demonstrated to be effective evidenced by the significant reduction of Lateral Order Index (LOI) from FTIR, reduction of Crystallinity Index (CI) based on XRD and the significant morphology changes indicated by SEM. The CI value for the pretreated OPF decreased from 0.47 (untreated sample) to 0.28 while the LOI value decreased from 1.10 to 0.24 after pretreatment with [EMIM]Ac and the SEM morphology showed that the pretreated OPF becomes distorted and disordered.

  16. Environmentally Friendly Pretreatment for Department of Defense Applications

    Science.gov (United States)

    2012-08-29

    Develop an environmentally friendly pretreatment system for multi-material Department of Defense applications ― Free of hexavalent chromium (Cr6...Zn phosphate and chrome wash primer •Two Zirconium pretreatment variations passed the 336 hr and 1000 hr B-117 outlined per MIL-DTL-53022 or MIL

  17. Physical protection

    International Nuclear Information System (INIS)

    Myers, D.A.

    1989-01-01

    Physical protection is defined and its function in relation to other functions of a State System of Accounting for and Control of Nuclear Materials is described. The need for a uniform minimum international standard for physical protection as well as the need for international cooperation in physical protection is emphasized. The IAEA's INFCIRC/225/Rev. 1 (Annex 1) is reviewed. The Convention on the Physical Protection of Nuclear Material (Annex 2) is discussed. Photographs show examples of typical physical protection technology (Annex 3)

  18. Diplomatic Protection

    OpenAIRE

    Režná, Jana

    2006-01-01

    Final thesis Topic: Diplomatic protection Thesis supervisor: JUDr. Vladimír Balaš, CSc. Student: Marek Čermák Thesis on the topic of diplomatic protection deals with the granting of exercise of diplomatic protection by the states and is divided into seven chapters which follow each other. The first chapter describes the diplomatic protection and its historical foundations. The second chapter focuses on the possibility of exercise of diplomatic protection in respect of natural persons and the ...

  19. Pretreatment of Biomass by Aqueous Ammonia for Bioethanol Production

    Science.gov (United States)

    Kim, Tae Hyun; Gupta, Rajesh; Lee, Y. Y.

    The methods of pretreatment of lignocellulosic biomass using aqueous ammonia are described. The main effect of ammonia treatment of biomass is delignification without significantly affecting the carbohydrate contents. It is a very effective pretreatment method especially for substrates that have low lignin contents such as agricultural residues and herbaceous feedstock. The ammonia-based pretreatment is well suited for simultaneous saccharification and co-fermentation (SSCF) because the treated biomass retains cellulose as well as hemicellulose. It has been demonstrated that overall ethanol yield above 75% of the theoretical maximum on the basis of total carbohydrate is achievable from corn stover pretreated with aqueous ammonia by way of SSCF. There are two different types of pretreatment methods based on aqueous ammonia: (1) high severity, low contact time process (ammonia recycle percolation; ARP), (2) low severity, high treatment time process (soaking in aqueous ammonia; SAA). Both of these methods are described and discussed for their features and effectiveness.

  20. Pretreatment of Cellulose By Electron Beam Irradiation Method

    Science.gov (United States)

    Jusri, N. A. A.; Azizan, A.; Ibrahim, N.; Salleh, R. Mohd; Rahman, M. F. Abd

    2018-05-01

    Pretreatment process of lignocellulosic biomass (LCB) to produce biofuel has been conducted by using various methods including physical, chemical, physicochemical as well as biological. The conversion of bioethanol process typically involves several steps which consist of pretreatment, hydrolysis, fermentation and separation. In this project, microcrystalline cellulose (MCC) was used in replacement of LCB since cellulose has the highest content of LCB for the purpose of investigating the effectiveness of new pretreatment method using radiation technology. Irradiation with different doses (100 kGy to 1000 kGy) was conducted by using electron beam accelerator equipment at Agensi Nuklear Malaysia. Fourier Transform Infrared Spectroscopy (FTIR) and X-Ray Diffraction (XRD) analyses were studied to further understand the effect of the suggested pretreatment step to the content of MCC. Through this method namely IRR-LCB, an ideal and optimal condition for pretreatment prior to the production of biofuel by using LCB may be introduced.

  1. Dielectric barrier discharge plasma pretreatment on hydrolysis of microcrystalline cellulose

    Science.gov (United States)

    Huang, Fangmin; Long, Zhouyang; Liu, Sa; Qin, Zhenglong

    2017-04-01

    Dielectric barrier discharge (DBD) plasma was used as a pretreatment method for downstream hydrolysis of microcrystalline cellulose (MCC). The degree of polymerization (DP) of MCC decreased after it was pretreated by DBD plasma under a carrier gas of air/argon. The effectiveness of depolymerization was found to be influenced by the crystallinity of MCC when under the pretreatment of DBD plasma. With the addition of tert-butyl alcohol in the treated MCC water suspension solution, depolymerization effectiveness of MCC was inhibited. When MCC was pretreated by DBD plasma for 30 min, the total reducing sugar concentration (TRSC) and liquefaction yield (LY) of pretreated-MCC (PMCC) increased by 82.98% and 34.18% respectively compared with those for raw MCC.

  2. Laboratory Tests on Post-Filtration Precipitation in the WTP Pretreatment Process

    International Nuclear Information System (INIS)

    Russell, Renee L.; Peterson, Reid A.; Rinehart, Donald E.; Crum, Jarrod V.

    2009-01-01

    Pacific Northwest National Laboratory (PNNL) has been tasked by Bechtel National Inc. (BNI) on the River Protection Project-Hanford Tank Waste Treatment and Immobilization Plant (RPP-WTP) project to perform research and development activities to resolve technical issues identified for the Pretreatment Facility (PTF). The Pretreatment Engineering Platform (PEP) was designed, constructed, and operated as part of a plan to respond to issue M12, 'Undemonstrated Leaching Processes,' of the External Flowsheet Review Team (EFRT) issue response plan (Barnes et al. 2006). The PEP is a 1/4.5-scale test platform designed to simulate the WTP pretreatment caustic leaching, oxidative leaching, ultrafiltration solids concentration, and slurry washing processes. The PEP replicates the WTP leaching processes using prototypic equipment and control strategies. A simplified flow diagram of the PEP system is shown in Figure 1.1. Two operating scenarios are currently being evaluated for the ultrafiltration process (UFP) and leaching operations. The first scenario has caustic leaching performed in the UFP-2 ultrafiltration feed vessels (i.e., vessel UFP-VSL-T02A in the PEP; and vessels UFP-VSL-00002A and B in the WTP PTF). The second scenario has caustic leaching conducted in the UFP-1 ultrafiltration feed preparation vessels (i.e., vessels UFP-VSL-T01A and B in the PEP; vessels UFP-VSL-00001A and B in the WTP PTF).

  3. Quinacrine pretreatment reduces microwave-induced neuronal damage by stabilizing the cell membrane

    Science.gov (United States)

    Ding, Xue-feng; Wu, Yan; Qu, Wen-rui; Fan, Ming; Zhao, Yong-qi

    2018-01-01

    Quinacrine, widely used to treat parasitic diseases, binds to cell membranes. We previously found that quinacrine pretreatment reduced microwave radiation damage in rat hippocampal neurons, but the molecular mechanism remains poorly understood. Considering the thermal effects of microwave radiation and the protective effects of quinacrine on heat damage in cells, we hypothesized that quinacrine would prevent microwave radiation damage to cells in a mechanism associated with cell membrane stability. To test this, we used retinoic acid to induce PC12 cells to differentiate into neuron-like cells. We then pretreated the neurons with quinacrine (20 and 40 mM) and irradiated them with 50 mW/cm2 microwaves for 3 or 6 hours. Flow cytometry, atomic force microscopy and western blot assays revealed that irradiated cells pretreated with quinacrine showed markedly less apoptosis, necrosis, and membrane damage, and greater expression of heat shock protein 70, than cells exposed to microwave irradiation alone. These results suggest that quinacrine stabilizes the neuronal membrane structure by upregulating the expression of heat shock protein 70, thus reducing neuronal injury caused by microwave radiation. PMID:29623929

  4. Size effects on acid bisulfite pretreatment efficiency: multiple product yields in spent liquor and enzymatic digestibility of pretreated solids

    Science.gov (United States)

    Yalan Liu; Jinwu Wang; Michael P. Wolcott

    2017-01-01

    Currently, feedstock size effects on chemical pretreatment performance were not clear due to the complexity of the pretreatment process and multiple evaluation standards such as the sugar recovery in spent liquor or enzymatic digestibility. In this study, we evaluated the size effects by various ways: the sugar recovery and coproduct yields in spent liquor, the...

  5. Low temperature lignocellulose pretreatment: effects and interactions of pretreatment pH are critical for maximizing enzymatic monosaccharide yields from wheat straw

    DEFF Research Database (Denmark)

    Pedersen, Mads; Johansen, Katja S.; Meyer, Anne S.

    2011-01-01

    Background: The recent development of improved enzymes and pentose-using yeast for cellulosic ethanol processes calls for new attention to the lignocellulose pretreatment step. This study assessed the influence of pretreatment pH, temperature, and time, and their interactions on the enzymatic...... alkaline pretreatments. Alkaline pretreatments also solubilized most of the lignin. Conclusions: Pretreatment pH exerted significant effects and factor interactions on the enzymatic glucose and xylose releases. Quite extreme pH values were necessary with mild thermal pretreatment strategies (T...... glucose and xylose yields from mildly pretreated wheat straw in multivariate experimental designs of acid and alkaline pretreatments. Results: The pretreatment pH was the most significant factor affecting both the enzymatic glucose and xylose yields after mild thermal pretreatments at maximum 140 degrees...

  6. Influence of wheat type and pretreatment on fungal growth in solid-state fermentation

    NARCIS (Netherlands)

    Hoogschagen, M.; Zhu, Y.; As, H. van; Tramper, J.; Rinzema, A.

    2001-01-01

    The respiration kinetics of Aspergillus oryzae on different varieties of whole wheat kernels were studied. Six wheat varieties were pretreated in two different ways. Five of the six substrates fermented similarly and independently of the pretreatment method. However, pretreatment affected

  7. Comparison of pre-treatment and post-treatment use of selenium in retinal ischemia reperfusion injury

    Directory of Open Access Journals (Sweden)

    Alper Yazici

    2015-04-01

    Full Text Available AIM: To investigate the effects of selenium in rat retinal ischemia reperfusion (IR model and compare pre-treatment and post-treatment use. METHODS: Selenium pre-treatment group (n=8 was treated with intraperitoneal (i.p. selenium 0.5 mg/kg for 7d and terminated 24h after the IR injury. Selenium post-treatment group (n=8 was treated with i.p. selenium 0.5 mg/kg for 7d after the IR injury with termination at the end of the 7d period. Sham group (n=8 received i.p. saline injections identical to the selenium volume for 7d with termination 24h after the IR injury. Control group (n=8 received no intervention. Main outcome measures were retina superoxide dismutase (SOD, glutathione (GSH, total antioxidant status (TAS, malondialdehyde (MDA, DNA fragmentation levels, and immunohistological apoptosis evaluation. RESULTS: Compared to the Sham group, selenium pre-treatment had a statistical difference in all parameters except SOD. Post-treatment selenium also resulted in statistical differences in all parameters except the MDA levels. When comparing selenium groups, the pre-treatment selenium group had a statistically higher success in reduction of markers of cell damage such as MDA and DNA fragmentation. In contrast, the post-selenium treatment group had resulted in statistically higher levels of GSH. Histologically both selenium groups succeeded to limit retinal thickening and apoptosis. Pre-treatment use was statistically more successful in decreasing apoptosis in ganglion cell layer compared to post-treatment use. CONCLUSION: Selenium was successful in retinal protection in IR injuries. Pre-treatment efficacy was superior in terms of prevention of tissue damage and apoptosis.

  8. Environmental protection

    International Nuclear Information System (INIS)

    Klinda, J.; Lieskovska, Z.

    1998-01-01

    In this chapter environmental protection in the Slovak Republic in 1997 are reviewed. The economics of environmental protection, state budget, Slovak state environmental fund, economic instruments, environmental laws, environmental impact assessment, environmental management systems, and environmental education are presented

  9. Effects of Pretreatment Methods on Electrodes and SOFC Performance

    Directory of Open Access Journals (Sweden)

    Guo-Bin Jung

    2014-06-01

    Full Text Available Commercially available tapes (anode, electrolyte and paste (cathode were choosen to prepare anode-supported cells for solid oxide fuel cell applications. For both anode-supported cells or electrolyte-supported cells, the anode needs pretreatment to reduce NiO/YSZ to Ni/YSZ to increase its conductivity as well as its catalytic characteristics. In this study, the effects of different pretreatments (open-circuit, closed-circuit on cathode and anodes as well as SOFC performance are investigated. To investigate the influence of closed-circuit pretreatment on the NiO/YSZ anode alone, a Pt cathode is utilized as reference for comparison with the LSM cathode. The characterization of the electrical resistance, AC impedance, and SOFC performance of the resulting electrodes and/or anode-supported cell were carried out. It’s found that the influence of open-circuit pretreatment on the LSM cathode is limited. However, the influence of closed-circuit pretreatment on both the LSM cathode and NiO/YSZ anode and the resulting SOFC performance is profound. The effect of closed-circuit pretreatment on the NiO/YSZ anode is attributed to its change of electronic/pore structure as well as catalytic characteristics. With closed-circuit pretreatment, the SOFC performance improved greatly from the change of LSM cathode (and Pt reference compared to the Ni/YSZ anode.

  10. Dilute alkali pretreatment of softwood pine: A biorefinery approach.

    Science.gov (United States)

    Safari, Ali; Karimi, Keikhosro; Shafiei, Marzieh

    2017-06-01

    Dilute alkali pretreatment was performed on softwood pine to maximize ethanol and biogas production via a biorefinery approach. Alkali pretreatments were performed with 0-2% w/v NaOH at 100-180°C for 1-5h. The liquid fraction of the pretreated substrates was subjected to anaerobic digestion. The solid fraction of the pretreatment was used for separate enzymatic hydrolysis and fermentation. High ethanol yields of 76.9‒78.0% were achieved by pretreatment with 2% (w/v) NaOH at 180°C. The highest biogas yield of 244mL/g volatile solid (at 25°C, 1bar) was achieved by the pretreatment with 1% (w/v) NaOH at 180°C. The highest gasoline equivalent (sum of ethanol and methane) of 197L per ton of pinewood and the lowest ethanol manufacturing cost of 0.75€/L was obtained after pretreatment with 1% NaOH at 180°C for 5h. The manufacturing cost of ethanol from untreated wood was 4.12€/L. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Effects of different pretreatment methods on fermentation types and dominant bacteria for hydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Ren, Nan-Qi; Guo, Wan-Qian; Liu, Bing-Feng; Wang, Xing-Zu; Ding, Jie; Chen, Zhao-Bo [State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, Heilongjiang (China); Wang, Xiang-Jing; Xiang, Wen-Sheng [Research Center of Life Science and Biotechnology, Northeast Agricultural University, Harbin 150030 (China)

    2008-08-15

    In order to enrich hydrogen producing bacteria and to establish high-efficient communities of the mixed microbial cultures, inoculum needs to be pretreated before the cultivation. Four pretreatment methods including heat-shock pretreatment, acid pretreatment, alkaline pretreatment and repeated-aeration pretreatment were performed on the seed sludge which was collected from a secondary settling tank of a municipal wastewater treatment plant. In contrast to the control test without any pretreatment, the heat-shock pretreatment, acid pretreatment and repeated-aeration pretreatment completely suppressed the methanogenic activity of the seed sludge, but the alkaline pretreatment did not. Employing different pretreatment methods resulted in the change in fermentation types as butyric-acid type fermentation was achieved by the heat-shock and alkaline pretreatments, mixed-acid type fermentation was achieved by acid pretreatment and the control, and ethanol-type fermentation was observed by repeated-aeration pretreatment. Denaturing gradient gel electrophoresis (DGGE) profiles revealed that pretreatment method substantially affected the species composition of microbial communities. The highest hydrogen yield of 1.96 mol/mol-glucose was observed with the repeated-aeration pretreatment method, while the lowest was obtained as the seed sludge was acidified. It is concluded that the pretreatment methods led to the difference in the initial microbial communities which might be directly responsible for different fermentation types and hydrogen yields. (author)

  12. 40 CFR 439.37 - Pretreatment standards for new sources (PSNS).

    Science.gov (United States)

    2010-07-01

    ...) EFFLUENT GUIDELINES AND STANDARDS PHARMACEUTICAL MANUFACTURING POINT SOURCE CATEGORY Chemical Synthesis... achieve the pretreatment standard for ammonia (as N). (b) The pretreatment standards for cyanide are as...

  13. Influence of ultrasound pretreatment on wood physiochemical structure.

    Science.gov (United States)

    He, Zhengbin; Wang, Zhenyu; Zhao, Zijian; Yi, Songlin; Mu, Jun; Wang, Xiaoxu

    2017-01-01

    As an initial step to increase the use of renewable biomass resources, this study was aimed at investigating the effects of ultrasound pretreatment on structural changes of wood. Samples were pretreated by ultrasound with the power of 300W and frequency of 28kHz in aqueous soda solution, aqueous acetic acid, or distilled water, then pretreated and control samples were characterized via X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA). The results shown that ultrasound pretreatment is indeed effective in modifying the physiochemical structure of eucalyptus wood; the pretreatment decreased the quantity of alkali metals (e.g., potassium, calcium and magnesium) in the resulting material. Compared to the control group, the residual char content of samples pretreated in aqueous soda solution increased by 10.08%-20.12% and the reaction temperature decreased from 361°C to 341°C, however, in samples pretreated by ultrasound in acetic solution or distilled water, the residual char content decreased by 12.40%-21.45% and there were no significant differences in reactivity apart from a slightly higher maximum reaction rate. Ultrasound pretreatment increased the samples' crystallinity up to 35.5% and successfully removed cellulose, hemicellulose, and lignin from the samples; the pretreatment also increased the exposure of the sample to the treatment solutions, broke down sample pits, and generated collapses and microchannels on sample pits, and removed attachments in the samples. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Investigation of Pleurotus ostreatus pretreatment on switchgrass for ethanol production

    Science.gov (United States)

    Slavens, Shelyn Gehle

    Fungal pretreatment using the white-rot fungus Pleurotus ostreatus on switchgrass for ethanol production was studied. In a small-scale storage study, small switchgrass bales were inoculated with fungal spawn and automatically watered to maintain moisture. Sampled at 25, 53, and 81 d, the switchgrass composition was determined and liquid hot water (LHW) pretreatment was conducted. Fungal pretreatment significantly decreased the xylan and lignin content; glucan was not significantly affected by fungal loading. The glucan, xylan, and lignin contents significantly decreased with increased fungal pretreatment time. The effects of the fungal pretreatment were not highly evident after the LHW pretreatment, showing only changes based on sampling time. Although other biological activity within the bales increased cellulose degradation, the fungal pretreatment successfully reduced the switchgrass lignin and hemicellulose contents. In a laboratory-scale nutrient supplementation study, copper, manganese, glucose, or water was added to switchgrass to induce production of ligninolytic enzymes by P. ostreatus. After 40 d, ligninolytic enzyme activities and biomass composition were determined and simultaneous saccharification and fermentation (SSF) was conducted to determine ethanol yield. Laccase activity was similar for all supplements and manganese peroxidase (MnP) activity was significantly less in copper-treated samples than in the other fungal-inoculated samples. The fungal pretreatment reduced glucan, xylan, and lignin content, while increasing extractable sugars content. The lowest lignin contents occurred in the water-fungal treated samples and produced the greatest ethanol yields. The greatest lignin contents occurred in the copper-fungal treated samples and produced the lowest ethanol yields. Manganese-fungal and glucose-fungal treated samples had similar, intermediate lignin contents and produced similar, intermediate ethanol yields. Ethanol yields from switchgrass

  15. Pretreatment of phosphoric acid of Annaba

    International Nuclear Information System (INIS)

    Kada, R.

    1990-03-01

    The most important step in the process of uranium recovery from phosphoric acid is the pretreatment operation. In this study, the adsorption of organic matters on activated carbon was carried out in a batch process and in a fixed bed column. First, the chemical and physical characterization of phosphoric acid, activated carbon and gypsum were performed. In addition, the organic matters were qualitatively analysed and a new and original quantitative method was experimented. Next, the various operating parameters such as agitation speed, granulometry, temperature, solid/liquid ratio, initial concentration, acid flowrate, and bed height were optimized. The experimental equilibrium isotherm was compared to the Langmuir, Freundlich, and Redlich-Peterson theoretical isotherms. It was noticed that the three models did not fit the experimental isotherm in the total concentration range. Thus, an original bilinear model was proposed. The influence of the operating conditions on the adsorption kinetics was also investigated. As a result of that, a new mathematical model was proposed to determine both the liquid and solid phases mass transfer and the solid phase diffusion coefficient. Finally, adsorption of organic matters on a fixed bed process allowed computation of the number of transfer units (NTU), the height of adsorption zone and the degree of saturation of activated carbon

  16. Combined (alkaline+ultrasonic) pretreatment effect on sewage sludge disintegration.

    Science.gov (United States)

    Kim, Dong-Hoon; Jeong, Emma; Oh, Sae-Eun; Shin, Hang-Sik

    2010-05-01

    The individual effects of alkaline (pH 8-13) and ultrasonic (3750-45,000kJ/kg TS) pretreatments on the disintegration of sewage sludge were separately tested, and then the effect of combining these two methods at different intensity levels was investigated using response surface methodology (RSM). In the combined pretreatment, ultrasonic treatment was applied to the alkali-pretreated sludge. While the solubilization (SCOD/TCOD) increase was limited to 50% in individual pretreatments, it reached 70% in combined pretreatment, and the results clearly showed that preconditioning of sludge at high pH levels played a crucial role in enhancing the disintegration efficiency of the subsequent ultrasonic pretreatment. By applying regression analysis, the disintegration degree (DD) was fitted based on the actual value to a second order polynomial equation: Y=-172.44+29.82X(1)+5.30x10(-3)X(2)-7.53x10(-5)X(1)X(2)-1.10X(1)(2)-1.043x10(-7)X(2)(2), where X(1), X(2), and Y are pH, specific energy input (kJ/kg TS), and DD, respectively. In a 2D contour plot describing the tendency of DD with respect to pH and specific energy input, it was clear that DD increased as pH increased, but it seemed that DD decreased when the specific energy input exceeded about 20,000kJ/kg TS. This phenomenon tells us that there exists a certain point where additional energy input is ineffective in achieving further disintegration. A synergetic disintegration effect was also found in the combined pretreatment, with lower specific energy input in ultrasonic pretreatment yielding higher synergetic effect. Finally, in order to see the combined pretreatment effect in continuous operation, the sludge pretreated with low intensity alkaline (pH 9)/ultrasonic (7500kJ/kg TS) treatment was fed to a 3 L of anaerobic sequencing batch reactor after 70 days of control operation. CH(4) production yield significantly increased from 81.9+/-4.5mL CH(4)/g COD(added) to 127.3+/-5.0mL CH(4)/g COD(added) by pretreatment, and

  17. Plasma-Assisted Pretreatment of Wheat Straw for Ethanol Production

    DEFF Research Database (Denmark)

    Schultz-Jensen, Nadja; Kádár, Zsófia; Thomsen, Anne Belinda

    2011-01-01

    (0–7 h), e.g., oxalic acid and acetovanillon. Interestingly, washing had no effect on the ethanol production with pretreatment times up to 1 h. Washing improved the glucose availability with pretreatment times of more than 2 h. One hour of ozonisation was found to be optimal for the use of washed...... carboxylic acids and phenolic compounds were found, e.g., vanillic acid, acetic acid, and formic acid. Some components had the highest concentration at the beginning of the ozonisation process (0.5, 1 h), e.g., 4-hydroxybenzladehyde, while the concentration of others increased during the entire pretreatment...

  18. Evaluation of wet oxidation pretreatment for enzymatic hydrolysis of softwood

    DEFF Research Database (Denmark)

    Palonen, H.; Thomsen, A.B.; Tenkanen, M.

    2004-01-01

    The wet oxidation pretreatment (water, oxygen, elevated temperature, and pressure) of softwood (Picea abies) was investigated for enhancing enzymatic hydrolysis. The pretreatment was preliminarily optimized. Six different combinations of reaction time, temperature, and pH were applied......, and the compositions of solid and liquid fractions were analyzed. The solid fraction after wet oxidation contained 58-64% cellulose, 2-16% hemicellulose, and 24-30% lignin. The pretreatment series gave information about the roles of lignin and hemicellulose in the enzymatic hydrolysis. The temperature...

  19. Protective relay

    International Nuclear Information System (INIS)

    Lim, Mu Ji; Jung, Hae Sang

    1974-10-01

    This book is divided into two chapters, which deals with protective relay. The first chapter deals with the basic knowledge of relay on development of relay, classification of protective relay, rating of protective relay general structure of protective relay, detecting of ground protection, about point of contact, operating relay and trip relaying. The second chapter is about structure and explanation of relay on classification by structure such as motor type and moving-coil type, explanation of other relays over current relay, over voltage relay, short voltage relay, relay for power, relay for direction, test of over voltage relay, test of short voltage relay and test of directional circuit relay.

  20. Protecting knowledge

    DEFF Research Database (Denmark)

    Sofka, Wolfgang; de Faria, Pedro; Shehu, Edlira

    2018-01-01

    Most firms use secrecy to protect their knowledge from potential imitators. However, the theoretical foundations for secrecy have not been well explored. We extend knowledge protection literature and propose theoretical mechanisms explaining how information visibility influences the importance...... of secrecy as a knowledge protection instrument. Building on mechanisms from information economics and signaling theory, we postulate that secrecy is more important for protecting knowledge for firms that have legal requirements to reveal information to shareholders. Furthermore, we argue that this effect...... and a firm's investment in fixed assets. Our findings inform both academics and managers on how firms balance information disclosure requirements with the use of secrecy as a knowledge protection instrument....

  1. Lignocellulosic biomass-Thermal pretreatment with steam: Pretreatment techniques for biofuels and biorefineries

    DEFF Research Database (Denmark)

    Toor, Saqib; Rosendahl, Lasse; Hoffmann, Jessica

    2013-01-01

    With the ever rising demand for more energy and the limited availability of depleted world resources, many are beginning to look for alternatives to fossil fuels. Liquid biofuel, in particular, is of key interest to decrease our dependency on fuels produced from imported petroleum. Biomass pre......-treatment remains one of the most pressing challenges in terms of cost-effective production of biofuels. The digestibility of lingo-cellulosic biomass is limited by different factors such as the lignin content, the crystallinity of cellulose, and the available cellulose accessibility to hydrolytic enzymes. A number...

  2. Comparison of aqueous ammonia and dilute acid pretreatment of bamboo fractions: Structure properties and enzymatic hydrolysis.

    Science.gov (United States)

    Xin, Donglin; Yang, Zhong; Liu, Feng; Xu, Xueru; Zhang, Junhua

    2015-01-01

    The effect of two pretreatments methods, aqueous ammonia (SAA) and dilute acid (DA), on the chemical compositions, cellulose crystallinity, morphologic change, and enzymatic hydrolysis of bamboo fractions (bamboo yellow, timber, green, and knot) was compared. Bamboo fractions with SAA pretreatment had better hydrolysability than those with DA pretreatment. High crystallinity index resulted in low hydrolysis yield in the conversion of SAA pretreated bamboo fractions, not DA pretreated fractions. The increase of cellulase loading had modestly positive effect in the hydrolysis of both SAA and DA pretreated bamboo fractions, while supplement of xylanase significantly increased the hydrolysis of the pretreated bamboo fractions, especially after SAA pretreatment. The results indicated that SAA pretreatment was more effective than DA pretreatment in conversion of bamboo fractions, and supplementation of xylanase was necessary in effective conversion of the SAA pretreated fractions into fermentable sugars. Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. Pretreatments to enhance the digestibility of lignocellulosic biomass

    NARCIS (Netherlands)

    Hendriks, A.T.W.M.; Zeeman, G.

    2009-01-01

    Lignocellulosic biomass represents a rather unused source for biogas and ethanol production. Many factors, like lignin content, crystallinity of cellulose, and particle size, limit the digestibility of the hemicellulose and cellulose present in the lignocellulosic biomass. Pretreatments have as a

  4. 40 CFR 407.76 - Pretreatment standards for new sources.

    Science.gov (United States)

    2010-07-01

    ... GUIDELINES AND STANDARDS CANNED AND PRESERVED FRUITS AND VEGETABLES PROCESSING POINT SOURCE CATEGORY Canned and Preserved Vegetables Subcategory § 407.76 Pretreatment standards for new sources. Any new source...

  5. 40 CFR 407.64 - Pretreatment standards for existing sources.

    Science.gov (United States)

    2010-07-01

    ...) EFFLUENT GUIDELINES AND STANDARDS CANNED AND PRESERVED FRUITS AND VEGETABLES PROCESSING POINT SOURCE CATEGORY Canned and Preserved Fruits Subcategory § 407.64 Pretreatment standards for existing sources. Any...

  6. 40 CFR 407.66 - Pretreatment standards for new sources.

    Science.gov (United States)

    2010-07-01

    ... GUIDELINES AND STANDARDS CANNED AND PRESERVED FRUITS AND VEGETABLES PROCESSING POINT SOURCE CATEGORY Canned and Preserved Fruits Subcategory § 407.66 Pretreatment standards for new sources. Any new source...

  7. Effects of Pretreatments in Convective Dehydration of Rosehip (Rosa eglanteria

    Directory of Open Access Journals (Sweden)

    Alejandra Mabellini

    2012-04-01

    Full Text Available The aim of this work was to experimentally determine drying curves for thin layer and bed drying of rosehip fruits, with and without pretreatments, to reduce processing times as a function of drying air operating variables, to propose dehydration kinetics of fruits and to determine its kinetic parameters for further use within drying simulation software. Fruits were pre-treated both chemically and mechanically, which included dipping the fruits in NaOH and ethyl oleate solutions; and cutting or perforating the fruit cuticle, respectively. Simulation models were then adopted to fit the kinetics drying data considering fruit volume shrinkage. These simple models minimized the calculation time during the simulation of deep-bed driers. Results show that pre-treatments reduced processing times up to 57%, and evaluated models satisfactorily predicted the drying of rosehip fruit. Effective mass diffusion coefficients were up to 4-fold greater when fruit was submitted to mechanical pretreatments.

  8. Pretreatment Characteristics of Waste Oak Wood by Ammonia Percolation

    Science.gov (United States)

    Kim, Jun-Seok; Kim, Hyunjoon; Lee, Jin-Suk; Lee, Joon-Pyo; Park, Soon-Chul

    A log of waste oak wood collected from a Korean mushroom farm has been tested for ammonia percolation pretreatment. The waste log has different physical characteristics from that of virgin oak wood. The density of the waste wood was 30% lower than that of virgin oak wood. However, there is little difference in the chemical compositions between the woods. Due to the difference in physical characteristics, the optimal pretreatment conditions were also quite different. While for waste oak the optimum temperature was determined to be 130°C, for virgin oak wood the optimum pretreatment was only achieved at 170°C. Presoaking for 12 h with ammonia solution before pretreatment was helpful to increase the delignification efficiency.

  9. Tank waste pretreatment issues, alternatives and strategies for resolution

    International Nuclear Information System (INIS)

    Miller, W.C.; Appel, J.; Barton, W.B.; Orme, R.M.; Holton, L.K. Jr.

    1993-02-01

    The US Department of Energy (DOE) has established the Tank Waste Remediation System (TWRS) to safely manage and dispose of the Hanford Site tank waste. The overall strategy for disposing of tank waste is evolving and initial recommendations on a course of action are expected in March, 1993. Pretreatment of these wastes may be required for one or both of the following reasons: (1) resolution of tank safety issues, and (2) preparation of low level and high level waste fractions for disposal. Pretreatment is faced with several issues that must be addressed by the deployment strategies that are being formulated. These issues are identified. There is also a discussion of several pretreatment deployment strategies and how these strategies address the issues. Finally, the technology alternatives that are being considered for the pretreatment function are briefly discussed

  10. Ensiling as pretreatment of grass for lignocellulosic biomass conversion

    DEFF Research Database (Denmark)

    Ambye-Jensen, Morten

    for subsequent enzymatic saccharification of cellulose and hemicellulose, by using the temperate grass Festulolium Hykor. The method was additionally combined with hydrothermal treatment, in order to decrease the required severity of an industrial applied pretreatment method. The first part of the project...... conditions providing the best possible pretreatment effect. The parameters were biomass composition, varied by ensiling of four seasonal cuts of grass, different dry matter (DM) content at ensiling, and an addition of different lactic acid bacteria species. First of all, the study confirmed that ensiling can...... act as a method of pretreatment and improve the enzymatic cellulose convertibility of grass. Furthermore, low DM ensiling was found to improve the effects of pretreatment due to a higher production of organic acids in the silage. The effect of applied lactic acid bacteria species was, however...

  11. Bioethanol from lignocellulose - pretreatment, enzyme immobilization and hydrolysis kinetics

    DEFF Research Database (Denmark)

    Tsai, Chien Tai

    , the cost of enzyme is still the bottle neck, re-using the enzyme is apossible way to reduce the input of enzyme in the process. In the point view of engineering, the prediction of enzymatic hydrolysis kinetics under different substrate loading, enzyme combination is usful for process design. Therefore...... lignocellulose is the required high cellulase enzyme dosages that increase the processing costs. One method to decrease the enzyme dosage is to re-use BG, which hydrolyze the soluble substrate cellobiose. Based on the hypothesis that immobilized BG can be re-used, how many times the enzyme could be recycled...... liquid and pretreatment time can be reduced, the influence of substrate concentration, pretreatment time and temperature were investigated and optimized. Pretreatment of barley straw by [EMIM]Ac, correlative models were constructed using 3 different pretreatment parameters (temperature, time...

  12. Synergistic Effect of Trehalose and Saccharose Pretreatment on ...

    African Journals Online (AJOL)

    maintenance of lyophilized human red blood cell (RBC) quality. Methods: RBCs were pre-treated with trehalose and saccharose, and then lyophilized and .... different concentrations of trehalose and saccharose as described above.

  13. Optimization of microwave pretreatment on wheat straw for ethanol production

    DEFF Research Database (Denmark)

    Xu, Jian; Chen, Hongzhang; Kádár, Zsófia

    2011-01-01

    An orthogonal design (L9(34)) was used to optimize the microwave pretreatment on wheat straw for ethanol production. The orthogonal analysis was done based on the results obtained from the nine pretreatments. The effect of four factors including the ratio of biomass to NaOH solution, pretreatment...... time, microwave power, and the concentration of NaOH solution with three different levels on the chemical composition, cellulose/hemicellulose recoveries and ethanol concentration was investigated. According to the orthogonal analysis, pretreatment with the ratio of biomass to liquid at 80 g kg−1......, the NaOH concentration of 10 kg m−3, the microwave power of 1000 W for 15 min was confirmed to be the optimal condition. The ethanol yield was 148.93 g kg−1 wheat straw at this condition, much higher than that from the untreated material which was only 26.78 g kg−1....

  14. New pentose dimers with bicyclic moieties from pretreated biomass

    DEFF Research Database (Denmark)

    Rasmussen, H.; Sørensen, Henrik Rokkjær; Tanner, David Ackland

    2017-01-01

    In lignocellulosic biorefinery processes involving enzyme catalysed reactions it is a challenge that enzyme inhibiting compounds are generated and liberated during pretreatment of the biomass. In this study the contribution to cellulase inhibition from xylooligosaccharides and newly discovered...... oligophenolic compounds from pilot scale pretreated wheat straw was assessed at two different pretreatment severities. An increase in severity of the pretreatment led to more oligophenol compounds and in turn the total overall cellulase inhibition increased. When the xylooligosaccharides were enzymatically...... degraded prior to cellulose hydrolysis, a relief in cellulase inhibition was observed, but some inhibition remained, suggesting that other components also played a role in inhibition. We propose that these components include dipentoses with bicyclic moieties and feruloylated tripentoses, because LC...

  15. Effect of Pretreatments on Seed Viability During Fruit Development ...

    African Journals Online (AJOL)

    Fiifi Baidoo

    and petri dishes on moist filter paper, gave 80% germination in variety gabonensis, 20 weeks after fruiting. .... Effect of pretreatments on seed germination of fruits of Irvingia gabonensis plucked from forest ...... A review of the tariff structure and.

  16. 40 CFR 405.86 - Pretreatment standards for new sources.

    Science.gov (United States)

    2010-07-01

    ... GUIDELINES AND STANDARDS DAIRY PRODUCTS PROCESSING POINT SOURCE CATEGORY Ice Cream, Frozen Desserts, Novelties and Other Dairy Desserts Subcategory § 405.86 Pretreatment standards for new sources. Any new...

  17. Bromine pretreated chitosan for adsorption of lead (II) from water

    Indian Academy of Sciences (India)

    isotherm and maximum sorption capacity of 30% bromine pretreated chitosan sorbent was 1·755 g/kg with 85–. 90% lead .... C by applying Lagergren first ... Lead (II) ions concentrations were determined by using an .... following equation.

  18. Effects of embryo induction media and pretreatments in isolated ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-11-16

    Nov 16, 2009 ... chemical + heat and also the effects of 5 embryo induction media (NPB-99, C17, ... Key words: Hexaploid wheat, haploid, isolated microspore culture, pretreatment, ..... this method is influenced by several mentioned factors.

  19. Improving biogas production from microalgae by enzymatic pretreatment.

    Science.gov (United States)

    Passos, Fabiana; Hom-Diaz, Andrea; Blanquez, Paqui; Vicent, Teresa; Ferrer, Ivet

    2016-01-01

    In this study, enzymatic pretreatment of microalgal biomass was investigated under different conditions and evaluated using biochemical methane potential (BMP) tests. Cellulase, glucohydrolase and an enzyme mix composed of cellulase, glucohydrolase and xylanase were selected based on the microalgae cell wall composition (cellulose, hemicellulose, pectin and glycoprotein). All of them increased organic matter solubilisation, obtaining high values already after 6h of pretreatment with an enzyme dose of 1% for cellulase and the enzyme mix. BMP tests with pretreated microalgae showed a methane yield increase of 8 and 15% for cellulase and the enzyme mix, respectively. Prospective research should evaluate enzymatic pretreatments in continuous anaerobic reactors so as to estimate the energy balance and economic cost of the process. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Pretreatment of Miscanthus for hydrogen production by Thermotoga elfii

    NARCIS (Netherlands)

    Vrije, de T.; Haas, de G.G.; Tan, G.B.; Keijsers, E.R.P.; Claassen, P.A.M.

    2002-01-01

    Pretreatment methods for the production of fermentable substrates from Miscanthus, a lignocellulosic biomass, were investigated. Results demonstrated an inverse relationship between lignin content and the efficiency of enzymatic hydrolysis of polysaccharides. High delignification values were

  1. Increased viability of fibroblasts when pretreated with ceria nanoparticles during serum deprivation

    Directory of Open Access Journals (Sweden)

    Genier FS

    2018-02-01

    Full Text Available Francielli S Genier,1 Maximilian Bizanek,1 Thomas J Webster,1,2 Amit K Roy1,2 1Department of Chemical Engineering, Northeastern University, Boston, MA, USA; 2Wenzhou Institute of Biomaterials and Engineering (WIBE, Wenzhou University, Wenzhou, People’s Republic of China Abstract: Conditions of cellular stress are often the cause of cell death or dysfunction. Sustained cell stress can lead to several health complications, such as extensive inflammatory responses, tumor growth, and necrosis. To prevent disease and protect human tissue during these conditions and to avoid medication side effects, nanomaterials with unique characteristics have been applied to biological systems. This paper introduces the pretreatment in human dermal fibroblasts with cerium oxide nanoparticles during nutritional stress. For this purpose, human dermal fibroblast cells received cell culture media with concentrations of 250 µg/mL and 500 µg/mL of nano-cerium oxide before being exposed to 24, 48, and 72 hours of serum starvation. Contrast images demonstrated higher cell confluence and cell integrity in cells pretreated with ceria nanoparticles compared to untreated cells. It was confirmed by MTS assay after 72 hours of serum starvation that higher cell viability was achieved with ceria nanoparticles. The results demonstrate the potential of cerium oxide nanoparticles as protective agents during cellular starvation. Keywords: cerium oxide, nanoparticles, serum starvation, human dermal fibroblasts

  2. Increased viability of fibroblasts when pretreated with ceria nanoparticles during serum deprivation.

    Science.gov (United States)

    Genier, Francielli S; Bizanek, Maximilian; Webster, Thomas J; Roy, Amit K

    2018-01-01

    Conditions of cellular stress are often the cause of cell death or dysfunction. Sustained cell stress can lead to several health complications, such as extensive inflammatory responses, tumor growth, and necrosis. To prevent disease and protect human tissue during these conditions and to avoid medication side effects, nanomaterials with unique characteristics have been applied to biological systems. This paper introduces the pretreatment in human dermal fibroblasts with cerium oxide nanoparticles during nutritional stress. For this purpose, human dermal fibroblast cells received cell culture media with concentrations of 250 µg/mL and 500 µg/mL of nano-cerium oxide before being exposed to 24, 48, and 72 hours of serum starvation. Contrast images demonstrated higher cell confluence and cell integrity in cells pretreated with ceria nanoparticles compared to untreated cells. It was confirmed by MTS assay after 72 hours of serum starvation that higher cell viability was achieved with ceria nanoparticles. The results demonstrate the potential of cerium oxide nanoparticles as protective agents during cellular starvation.

  3. Pretreatment with Fish Oil-Based Lipid Emulsion Modulates Muscle Leukocyte Chemotaxis in Murine Model of Sublethal Lower Limb Ischemia

    Directory of Open Access Journals (Sweden)

    Yao-Ming Shih

    2017-01-01

    Full Text Available This study investigated the effects of a fish oil- (FO- based lipid emulsion on muscle leukocyte chemotaxis and inflammatory responses in a murine model of limb ischemia-reperfusion (IR injury. Mice were assigned randomly to 1 sham (sham group, 2 ischemic groups, and 2 IR groups. The sham group did not undergo the ischemic procedure. The mice assigned to the ischemic or IR groups were pretreated intraperitoneally with either saline or FO-based lipid emulsion for 3 consecutive days. The IR procedure was induced by applying a 4.5 oz orthodontic rubber band to the left thigh above the greater trochanter for 120 min and then cutting the band to allow reperfusion. The ischemic groups were sacrificed immediately while the IR groups were sacrificed 24 h after reperfusion. Blood, IR-injured gastrocnemius, and lung tissues were collected for analysis. The results showed that FO pretreatment suppressed the local and systemic expression of several IR-induced proinflammatory mediators. Also, the FO-pretreated group had lower blood Ly6ChiCCR2hi monocyte percentage and muscle M1/M2 ratio than the saline group at 24 h after reperfusion. These findings suggest that FO pretreatment may have a protective role in limb IR injury by modulating the expression of proinflammatory mediators and regulating the polarization of macrophage.

  4. Effect of Pre-treatment with Moringa oleifera (Drumstick Leaves on Diabetogenesis Produced by Alloxan in Rats

    Directory of Open Access Journals (Sweden)

    Shamsun Nahar

    2015-07-01

    Full Text Available Background: Medicinal plants constitute an important source of potential therapeutic agents for diabetes. Objective: In the study, we aimed to investigate the pre-treatment effect or preventive effects of Moringa oleifera (MO leaves on blood sugar of rats. Materials and method: This experimental study was carried out in the department of Pharmacology and Therapeutics of Sir Salimullah Medical College in collaboration with Bangladesh Council of Scientific and Industrial Research (BCSIR, Dhaka. A total 24 long Evans rats were included in this study and divided in to four groups. Hyperglycemia was induced on rats using alloxan (100 mg/kg body weight, intraperitioneally. Blood sample was collected from tail vein by tail tipping method. Pre-treatment effect or preventive role of Moringa oleifera (drumstick leaf powder on diabetogenesis produced by Alloxan in rats was tested by giving 50 mg/rat/day Moringa oleifera leaf powder for 14 days orally as pre-treatment along with standard rat feed. Then alloxan was administered intraperitoneally on 15th day of the experiment and 50mg/rat/day Moringa oleifera leaf powder was given for 7 days as post-treatment. Results: No significant effect of MO on blood glucose level was observed on normal rats and non significant hypoglycaemic effect was found in rats that were pretreated with MO. Conclusion: The present study suggests that Moringa oleifera leaf powder did not produce any significant protective effect in diabetogenesis produced by alloxan though it has hypoglycaemic effect.

  5. Pretreatment seizure semiology in childhood absence epilepsy.

    Science.gov (United States)

    Kessler, Sudha Kilaru; Shinnar, Shlomo; Cnaan, Avital; Dlugos, Dennis; Conry, Joan; Hirtz, Deborah G; Hu, Fengming; Liu, Chunyan; Mizrahi, Eli M; Moshé, Solomon L; Clark, Peggy; Glauser, Tracy A

    2017-08-15

    To determine seizure semiology in children with newly diagnosed childhood absence epilepsy and to evaluate associations with short-term treatment outcomes. For participants enrolled in a multicenter, randomized, double-blind, comparative-effectiveness trial, semiologic features of pretreatment seizures were analyzed as predictors of treatment outcome at the week 16 to 20 visit. Video of 1,932 electrographic absence seizures from 416 participants was evaluated. Median seizure duration was 10.2 seconds; median time between electrographic seizure onset and clinical manifestation onset was 1.5 seconds. For individual seizures and by participant, the most common semiology features were pause/stare (seizure 95.5%, participant 99.3%), motor automatisms (60.6%, 86.1%), and eye involvement (54.9%, 76.5%). The interrater agreement for motor automatisms and eye involvement was good (72%-84%). Variability of semiology features between seizures even within participants was high. Clustering analyses revealed 4 patterns (involving the presence/absence of eye involvement and motor automatisms superimposed on the nearly ubiquitous pause/stare). Most participants experienced more than one seizure cluster pattern. No individual semiologic feature was individually predictive of short-term outcome. Seizure freedom was half as likely in participants with one or more seizure having the pattern of eye involvement without motor automatisms than in participants without this pattern. Almost all absence seizures are characterized by a pause in activity or staring, but rarely is this the only feature. Semiologic features tend to cluster, resulting in identifiable absence seizure subtypes with significant intraparticipant seizure phenomenologic heterogeneity. One seizure subtype, pause/stare and eye involvement but no motor automatisms, is specifically associated with a worse treatment outcome. © 2017 American Academy of Neurology.

  6. Alkaline pretreatment of Mexican pine residues for bioethanol ...

    African Journals Online (AJOL)

    CLAUDIA

    2013-07-31

    Jul 31, 2013 ... 120°C. The pretreated blending was subjected to enzymatic hydrolysis for 130 h at 80 rpm and 50°C with an enzymatic load of ... pretreatment of 2.5% NaOH for 90 min, 120°C, and a hydrolysis residence time of 130 h. The removal of ...... Programa Estratégico Forestal para el estado de Durango,. México.

  7. Wet oxidation pretreatment of rape straw for ethanol production

    International Nuclear Information System (INIS)

    Arvaniti, Efthalia; Bjerre, Anne Belinda; Schmidt, Jens Ejbye

    2012-01-01

    Rape straw can be used for production of second generation bioethanol. In this paper we optimized the pretreatment of rape straw for this purpose using Wet oxidation (WO). The effect of reaction temperature, reaction time, and oxygen gas pressure was investigated for maximum ethanol yield via Simultaneous Saccharification and Fermentation (SSF). To reduce the water use and increase the energy efficiency in WO pretreatment features like recycling liquid (filtrate), presoaking of rape straw in water or recycled filtrate before WO, skip washing pretreated solids (filter cake) after WO, or use of whole slurry (Filter cake + filtrate) in SSF were also tested. Except ethanol yields, pretreatment methods were evaluated based on achieved glucose yields, amount of water used, recovery of cellulose, hemicellulose, and lignin. The highest ethanol yield obtained was 67% after fermenting the whole slurry produced by WO at 205 °C for 3 min with 12 bar of oxygen gas pressure and featured with presoaking in water. At these conditions after pre-treatment, cellulose and hemicellulose was recovered quantitatively (100%) together with 86% of the lignin. WO treatments of 2–3 min at 205–210 °C with 12 bar of oxygen gas produced higher ethanol yields and cellulose, hemicelluloses, and lignin recoveries, than 15 min WO treatment at 195 °C. Also, recycling filtrate and use of higher oxygen gas pressure reduced recovery of materials. The use of filtrate could be inhibitory for the yeast, but also reduced lactic acid formation in SSF. -- Highlights: ► Wet Oxidation pretreatment on rape straw for sugar and ethanol production. ► Variables were reaction time, temperature, and oxygen gas pressure. ► Also, other configurations for increase of water and energy efficiency. ► Short Wet oxidation pretreatment (2–3 min) produced highest ethanol yield. ► After these pretreatment conditions recovery of lignin in solids was 86%.

  8. Pretreatment of wheat straw for fermentation to methane

    International Nuclear Information System (INIS)

    Hashimoto, A.G.

    1986-01-01

    The effects of pretreating wheat straw with gamma-ray irradiation, ammonium hydroxide, and sodium hydroxide on methane yield, fermentation rate constant, and loss of feedstock constituents were evaluated using laboratory-scale batch fermentors. Results showed that methane yield increased as pretreatment alkali concentration increased, with the highest yield being 37% over untreated straw for the pretreatment consisting of sodium hydroxide dosage of 34 g OH - /kg volatile solids, at 90 0 C for 1 h. Gamma-ray irradiation had no significant effect on methane yield. Alkaline pretreatment temperatures above 100 0 C caused a decrease in methane yield. After more than 100 days of fermentation, all of the hemicellulose and more than 80% of the cellulose were degraded. The loss in cellulose and hemicellulose accounted for 100% of the volatile solids lost. No consistent effect of pretreatments on batch fermentation rates was noted. Semicontinuous fermentations of straw-manure mixtures confirmed the relative effectiveness of sodium- and ammonium-hydroxide pretreatments

  9. Effect of alkaline pretreatment on anaerobic digestion of solid wastes

    International Nuclear Information System (INIS)

    Lopez Torres, M.; Espinosa Llorens, Ma. del C.

    2008-01-01

    The introduction of the anaerobic digestion for the treatment of the organic fraction of municipal solid waste (OFMSW) is currently of special interest. The main difficulty in the treatment of this waste fraction is its biotransformation, due to the complexity of organic material. Therefore, the first step must be its physical, chemical and biological pretreatment for breaking complex molecules into simple monomers, to increase solubilization of organic material and improve the efficiency of the anaerobic treatment in the second step. This paper describes chemical pretreatment based on lime addition (Ca(OH) 2 ), in order to enhance chemical oxygen demand (COD) solubilization, followed by anaerobic digestion of the OFMSW. Laboratory-scale experiments were carried out in completely mixed reactors, 1 L capacity. Optimal conditions for COD solubilization in the first step of pretreatment were 62.0 mEq Ca(OH) 2 /L for 6.0 h. Under these conditions, 11.5% of the COD was solubilized. The anaerobic digestion efficiency of the OFMSW, with and without pretreatment, was evaluated. The highest methane yield under anaerobic digestion of the pretreated waste was 0.15 m 3 CH 4 /kg volatile solids (VS), 172.0% of the control. Under that condition the soluble COD and VS removal were 93.0% and 94.0%, respectively. The results have shown that chemical pretreatment with lime, followed by anaerobic digestion, provides the best results for stabilizing the OFMSW

  10. Removal mechanism of tritium by variously pretreated silica gel

    International Nuclear Information System (INIS)

    Nakashima, M.; Tachikawa, E.; Saeki, M.; Aratono, Y.

    1981-01-01

    Removal mechanisms of HTO from variously pretreated and non-pretreated silica gel columns were investigated with pulse-loading with tritiated water vapor. With non-pretreated silica gel, the HTO physisorbed on the upper part of the column comes into contact with surface hydroxyl groups while passing downward the column, so that in each equilibration a part of the tritium is incorporated into hydroxyl groups by H/T isotopic exchange reactions. With the silica gel pretreated at a temperature below 400 0 C, most of tritium in the applied HTO is easily incorporated into surface hydroxyl groups in the upper part of the column either by H/T isotopic exchange reactions or by rehydration of the dehydrated surface (siloxyl linkage). In the pretreatment above 400 0 C, essentially all the tritium is trapped by siloxyl groups of various stabilities. The ease of rehydration of siloxyl groups by applied HTO depends on their stabilities, which, in turn, depend on the pretreatment temperature. As a general trend, treatment at higher temperature promotes annealing of the constrained siloxyl groups and thus the rate of rehydration becomes slower. (author)

  11. Optimization and evaluation of alkaline potassium permanganate pretreatment of corncob.

    Science.gov (United States)

    Ma, Lijuan; Cui, Youzhi; Cai, Rui; Liu, Xueqiang; Zhang, Cuiying; Xiao, Dongguang

    2015-03-01

    Alkaline potassium permanganate solution (APP) was applied to the pretreatment of corncob with a simple and effective optimization of APP concentration, reaction time, temperature and solid to liquid ratio (SLR). The optimized pretreatment conditions were at 2% (w/v) potassium permanganate with SLR of 1:10 treating for 6h at 50°C. This simple one-step treatment resulted in significant 94.56% of the cellulose and 81.47% of the hemicellulose recoveries and 46.79% of the lignin removal of corncob. The reducing sugar in the hydrolysate from APP-pretreated corncob was 8.39g/L after 12h enzymatic hydrolysis, which was 1.44 and 1.29 folds higher than those from raw and acid pretreated corncobs. Physical characteristics, crystallinity and structure of the pretreated corncob were analyzed and assessed by SEM, XRD and FTIR. The APP pretreatment process was novel and enhanced enzymatic hydrolysis of lignocellulose by affecting composition and structural features. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. The effect of levocabastine and furosemide pretreatment on hyperreactive response after nasal provocation with hypotonic aerosol in subjects with allergic rhinitis.

    Science.gov (United States)

    Anzic, Srdjan Ante; Dzepina, Davor; Kalogjera, Livije

    2007-11-01

    Patients with allergic rhinitis demonstrate hyperreactive response in distilled water nasal provocation, shown by significant increase in nasal airway resistance (NAR). Antihistamines, including topical antihistamine, levocabastine, reduce response in non-specific nasal provocation tests. Furosemide is a diuretic which reduces hyperreactivity in lower airways, but the mode of its action is not yet fully understood. In this study, we hypothesized that either levocabastine or furosemide pre-treatment in allergic rhinitis patients reduced response to nasal challenge with non-isotonic aerosol. To test the hypothesis, we measured the effect of pre-treatment with levocabastine and furosemide in topical application on suppression of hyperreactive response to distilled water nasal inhalation. Nasal resistance was measured, prior to and after the provocation, by active anterior rhinomanometry in two randomized groups of patients, according to pre-treatment, either by levocabastine or furosemide, 20 patients in each group, respectively. Nasal airflow resistance and level of hyperreactive response considering nasal eosinophilia were tested. Significant increase in nasal resistance following provocation was found at baseline conditions (without pre-medication); pre-treatment with levocabastine and furosemide has suppressed such response. Patients with positive nasal eosinophilia showed a significantly higher increase in nasal resistance compared to those with negative smears. Furosemide has shown significantly better protective effect on nasal resistance increase in patients with positive eosinophils nasal smears. Levocabastine and furosemide pre-treatment suppress hyperreactive response to distilled water nasal provocation. Comparison of resistances (pre-treatment vs. without) showed more protective effect of furosemide, measured on both better and worse patent side of nose, in contrast to levocabastine group for which it was shown only on better patent side prior to

  13. Investigation of the impacts of thermal pretreatment on waste activated sludge and development of a pretreatment model.

    Science.gov (United States)

    Burger, Gillian; Parker, Wayne

    2013-09-15

    This study investigated the impacts of high pressure thermal hydrolysis (HPTH) pretreatment on the distribution of chemical oxygen demand (COD) species in waste activated sludge (WAS). In the first phase of the project, WAS from a synthetically-fed biological reactor (BR) was fed to an aerobic digester (AD). In the second phase, WAS from the BR was pretreated by HPTH at 150 °C and 3 bars for 30 min prior to being fed to the AD. A range of physical, biochemical and biological properties were regularly measured in each process stream in both phases. The COD of the BR WAS consisted of storage products (XSTO), active heterotrophs (XH) and endogenous decay products (XE). Pretreatment did not increase the extent to which the BR WAS was aerobically digested and hence it was concluded that the unbiodegradable COD fraction, i.e. XE, was unchanged by pretreatment. However, pretreatment did increase the rate of degradation as it converted 36% of XH to readily biodegradable COD (SB) and the remaining XH to slowly biodegradable COD (XB). Furthermore, XSTO was fully converted to SB by pretreatment. Although pretreatment did not change the VSS concentration in the downstream aerobic digester, it did decrease the ISS concentration by 46 ± 11%. This reduced the total mass of solids produced by the digester by 21 ± 8%. A COD-based HPTH pretreatment model was developed and calibrated. When this model was integrated into BioWin 3.1(®), it was able to accurately simulate both the steady state performance of the overall system employed in this study as well as dynamic respirometry results. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. Techniques and practices for pretreatment of low and intermediate level solid and liquid radioactive wastes

    International Nuclear Information System (INIS)

    1987-01-01

    An overall waste management strategy generally includes several components: pretreatment, treatment, conditioning, transport and disposal. Benefits of pretreatment are improved safety, lower radiation exposures and significantly lower costs in subsequent waste management operations. This publication reviews current practices in the pretreatment of wastes in different countries and may assist the specialist in selection of appropriate pretreatment techniques

  15. Biomass pretreatment affects Ustilago maydis in producing itaconic acid

    Directory of Open Access Journals (Sweden)

    Klement Tobias

    2012-04-01

    Full Text Available Abstract Background In the last years, the biotechnological production of platform chemicals for fuel components has become a major focus of interest. Although ligno-cellulosic material is considered as suitable feedstock, the almost inevitable pretreatment of this recalcitrant material may interfere with the subsequent fermentation steps. In this study, the fungus Ustilago maydis was used to produce itaconic acid as platform chemical for the synthesis of potential biofuels such as 3-methyltetrahydrofuran. No studies, however, have investigated how pretreatment of ligno-cellulosic biomass precisely influences the subsequent fermentation by U. maydis. Thus, this current study aims to first characterize U. maydis in shake flasks and then to evaluate the influence of three exemplary pretreatment methods on the cultivation and itaconic acid production of this fungus. Cellulose enzymatically hydrolysed in seawater and salt-assisted organic-acid catalysed cellulose were investigated as substrates. Lastly, hydrolysed hemicellulose from fractionated beech wood was applied as substrate. Results U. maydis was characterized on shake flask level regarding its itaconic acid production on glucose. Nitrogen limitation was shown to be a crucial condition for the production of itaconic acid. For itaconic acid concentrations above 25 g/L, a significant product inhibition was observed. Performing experiments that simulated influences of possible pretreatment methods, U. maydis was only slightly affected by high osmolarities up to 3.5 osmol/L as well as of 0.1 M oxalic acid. The production of itaconic acid was achieved on pretreated cellulose in seawater and on the hydrolysed hemicellulosic fraction of pretreated beech wood. Conclusion The fungus U. maydis is a promising producer of itaconic acid, since it grows as single cells (yeast-like in submerged cultivations and it is extremely robust in high osmotic media and real seawater. Moreover, U. maydis can grow on

  16. Radiation Protection

    International Nuclear Information System (INIS)

    Loos, M.

    2002-01-01

    Major achievements of SCK-CEN's Radiation Protection Department in 2001 are described. The main areas for R and D of the department are enviromnental remediation, emergency planning, radiation protection research, low-level radioactvity measurements, safeguards and physics measurements, decision strategy research and policy support and social sciences in nuclear research. Main achievements for 2001 in these areas are reported

  17. Sun protection

    Science.gov (United States)

    ... sun exposure. The start of summer is when UV rays can cause the most skin damage. Use sun protection, even on cloudy days. Clouds and haze don't protect you from the sun. Avoid surfaces that reflect light, such as water, sand, concrete, snow, and areas ...

  18. Comparison the effects of nitric oxide and spermidin pretreatment on alleviation of salt stress in chamomile plant (Matricaria recutita L.

    Directory of Open Access Journals (Sweden)

    Fazelian Nasrin

    2012-08-01

    Full Text Available Salt stress is an important environmental stress that produces reactive oxygen species in plants and causes oxidative injuries. In this investigation, salt stress reduced the shoot and root length, while increased the content of malondealdehyde, Hydrogen peroxide, and the activity of Ascorbate peroxidase andguaiacol peroxidase. Pretreatment of chamomile plants under salt stress with sodium nitroprussideand Spermidin caused enhancement of growth parameters and reduction of malondealdehyde and Hydrogen peroxide content. Pretreatment of plants with sodium nitroprusside remarkably increased Ascorbate peroxidase activity, while Spermidin pre-treatment significantly increased guaiacol peroxidase activity. Application of sodium nitroprusside or Spermidin with Methylene blue which is known to block cyclic guanosine monophosphate signaling pathway, reduced the protective effects of sodium nitroprussideand Spermidin in plants under salinity condition. The result of this study indicated that Methylene blue could partially and entirely abolish the protective effect of Nitric oxide on some physiological parameter. Methylene blue also has could reduce the alleviation effect of Spermidin on some of parameters in chamomile plant under salt stress, so with comparing the results of this study it seems that Spermidin probably acts through Nitric oxide pathway, but the use of 2-4- carboxyphenyl- 4,4,5,5- tetramethyl-imidazoline-1-oxyl-3-oxide is better to prove.

  19. Nanostructured sol-gel coatings doped with cerium nitrate as pre-treatments for AA2024-T3

    International Nuclear Information System (INIS)

    Zheludkevich, M.L.; Serra, R.; Montemor, M.F.; Yasakau, K.A.; Salvado, I.M. Miranda; Ferreira, M.G.S.

    2005-01-01

    Nanostructured hybrid sol-gel coatings doped with cerium ions were investigated in the present work as pre-treatments for the AA2024-T3 alloy. The sol-gel films have been synthesized from tetraethylorthosilicate (TEOS) and 3-glycidoxypropyltrimethoxysilane (GPTMS) precursors. Additionally the hybrid sol was doped with zirconia nanoparticles prepared from hydrolyzed tetra-n-propoxyzirconium (TPOZ). Cerium nitrate, as corrosion inhibitor, was added into the hybrid matrix or into the oxide nanoparticles. The chemical composition and the structure of the hybrid sol-gel films were studied by XPS (X-ray photoelectron spectroscopy) and AFM (atomic force microscopy), respectively. The evolution of the corrosion protection properties of the sol-gel films was studied by EIS (electrochemical impedance spectroscopy), which can provide quantitative information on the role of the different pre-treatments. Different equivalent circuits, for different stages of the corrosion processes, were used in order to model the coating degradation. The models were supported by SEM (scanning electron microscopy) measurements. The results show that the sol-gel films containing zirconia nanoparticles present improved barrier properties. Doping the hybrid nanostructured sol-gel coatings with cerium nitrate leads to additional improvement of the corrosion protection. The zirconia particles present in the sol-gel matrix seem to act as nanoreservoirs providing a prolonged release of cerium ions. The nanostructured sol-gel films doped with cerium nitrate can be proposed as a potential candidate for substitution of the chromate pre-treatments for AA2024-T3

  20. The Role of Praziquantel- chemoprophylaxis and UV-attenuated Vaccine in Protecting Mice Against S. Mansoni Infection

    International Nuclear Information System (INIS)

    Gad, H.S.M.

    1999-01-01

    Potential control of schistosomiasis rely on multiple and integrated strategies, including vaccine production, chemotherapy and combination between chemotherapy and vaccination. The present work was conducted to evaluate the efficacy of combined PZQ- treatment with PZQ-chemoprophylaxis (PZQ-pretreatment) and UV-attenuated cercarial vaccination for the control of schistosomiasis. In the present work the induced levels of protection induced in vaccinated and vaccinated-PZQ-treated as well as, PZQ-pretreated and PZQ-pretreated followed by PZQ-treatment will be discussed. Results revealed that UV-Irradiated Vaccinated and vaccinated-PZQ-treated and PZQ-pretreated followed by PZQ-treated post challenged groups induced high levels of worm burdens reduction and mild pathological changes in both liver and intestine. Meanwhile, PZQ-pretreated alone failed to induce significant protection

  1. Enhanced fermentable sugar production from kitchen waste using various pretreatments.

    Science.gov (United States)

    Hafid, Halimatun Saadiah; Rahman, Nor'Aini Abdul; Md Shah, Umi Kalsom; Baharudin, Azhari Samsu

    2015-06-01

    The kitchen waste fraction in municipal solid waste contains high organic matter particularly carbohydrate that can contribute to fermentable sugar production for subsequent conversion to bioethanol. This study was carried out to evaluate the influence of single and combination pretreatments of kitchen waste by liquid hot water, mild acid pretreatment of hydrochloric acid (HCl) and sulphuric acid (H2SO4) and enzymatic hydrolysis (glucoamylase). The maximum total fermentable sugar produced after combination pretreatment by 1.5% HCl and glucoamylase consisted of 93.25 g/L glucose, 0.542 g/L sucrose, 0.348 g/L maltose, and 0.321 g/L fructose. The glucose released by the combination pretreatment method was 0.79 g glucose/g KW equivalent to 79% of glucose conversion. The effects of the pre-treatment on kitchen waste indicated that the highest solubilization was 40% by the combination method of 1.5% HCl and glucoamylase. The best combination pre-treatment gave concentrations of lactic acid, acetic acid, and propionic acid of 11.74 g/L, 6.77 g/L, and 1.02 g/L, respectively. The decrease of aliphatic absorbance bands of polysaccharides at 2851 and 2923 cm(-1) and the increase on structures of carbonyl absorbance bands at 1600 cm(-1) reflects the progress of the kitchen waste hydrolysis to fermentable sugars. Overall, 1.5% HCl and glucoamylase treatment was the most profitable process as the minimum selling price of glucose was USD 0.101/g kitchen waste. Therefore, the combination pretreatment method was proposed to enhance the production of fermentable sugar, particularly glucose from kitchen waste as the feedstock for bioethanol production. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Study of Enzymatic Hydrolysis of Dilute Acid Pretreated Coconut Husk

    Directory of Open Access Journals (Sweden)

    Rudy Agustriyanto

    2012-12-01

    Full Text Available Coconut husk is classified as complex lignocellulosic material that contains cellulose, hemicellulose, lignin, and some other extractive compounds. Cellulose from coconut husk can be used as fermentation substrate after enzymatic hydrolysis. In contrary, lignin content from the coconut husk will act as an inhibitor in this hydrolysis process. Therefore, a pretreatment process is needed to enhance the hydrolysis of cellulose. The objective of this research is to investigate the production of the glucose through dilute acid pretreatment and to obtain its optimum operating conditions. In this study, the pretreatment was done using dilute sulfuric acid in an autoclave reactor. The pretreatment condition were varied at 80°C, 100°C, 120°C and 0.9%, 1.2%, 1.5% for temperature and acid concentration respectively. The acid pretreated coconut husk was then hydrolyzed using commercial cellulase (celluclast and β-glucosidase (Novozyme 188. The hydrolysis time was 72 hours and the operating conditions were varied at several temperature and pH. From the experimental results it can be concluded that the delignification temperature variation has greater influence than the acid concentration. The optimum operating condition was obtained at pH 4 and 50°C which was pretreated at 100°C using 1.5% acid concentration. Copyright © 2012 by BCREC UNDIP. All rights reserved. (Selected Paper from International Conference on Chemical and Material Engineering (ICCME 2012Received: 28th September 2012, Revised: 2nd October 2012, Accepted: 4th October 2012[How to Cite: R. Agustriyanto, A. Fatmawati, Y. Liasari. (2012. Study of Enzymatic Hydrolysis of Dilute Acid Pretreated Coconut Husk. Bulletin of Chemical Reaction Engineering & Catalysis, 7(2: 137-141. doi:10.9767/bcrec.7.2.4046.137-141] [How to Link / DOI: http://dx.doi.org/10.9767/bcrec.7.2.4046.137-141 ] | View in 

  3. An improved technology for decontaminating ruthenium in uranium purification cycle by hydroxylamine pretreatment

    International Nuclear Information System (INIS)

    Qi Zhanshun; Zhu Zhixuan; Zhang Pilu

    1996-01-01

    The Influences of hydroxylamine concentration, pretreatment time, acidity and the concentration of stabilizer have been studied, and the best pretreatment condition for the improvement of Ru decontamination in uranium purification cycle by hydroxylamine pretreatment has been obtained. The results show that no satisfactory result can be obtained by solely using hydroxylamine as pretreatment agent unless a small amount of hydrazine is added into the pretreatment system as stabilizer

  4. Pretreatment Engineering Platform (PEP) Integrated Test B Run Report--Caustic and Oxidative Leaching in UFP-VSL-T02A

    Energy Technology Data Exchange (ETDEWEB)

    Geeting, John GH; Bredt, Ofelia P.; Burns, Carolyn A.; Golovich, Elizabeth C.; Guzman-Leong, Consuelo E.; Josephson, Gary B.; Kurath, Dean E.; Sevigny, Gary J.; Aaberg, Rosanne L.

    2009-12-10

    Pacific Northwest National Laboratory (PNNL) has been tasked by Bechtel National Inc. (BNI) on the River Protection Project-Hanford Tank Waste Treatment and Immobilization Plant (RPP-WTP) project to perform research and development activities to resolve technical issues identified for the Pretreatment Facility (PTF). The Pretreatment Engineering Platform (PEP) was designed, constructed and operated as part of a plan to respond to issue M12, “Undemonstrated Leaching Processes” of the External Flowsheet Review Team (EFRT) issue response plan.( ) The PEP is a 1/4.5-scale test platform designed to simulate the WTP pretreatment caustic leaching, oxidative leaching, ultrafiltration solids concentration, and slurry washing processes. The PEP replicates the WTP leaching processes using prototypic equipment and control strategies. The PEP also includes non-prototypic ancillary equipment to support the core processing.

  5. Autohydrolysis pretreatment assessment in ethanol production from agave bagasse.

    Science.gov (United States)

    Rios-González, Leopoldo J; Morales-Martínez, Thelma K; Rodríguez-Flores, María F; Rodríguez-De la Garza, José A; Castillo-Quiroz, David; Castro-Montoya, Agustín J; Martinez, Alfredo

    2017-10-01

    The aim of the present work was to assess the autohydrolysis pretreatment of Agave tequilana bagasse for ethanol production. The pretreatment was conducted using a one-liter high pressure Parr reactor under different severity factors (SF) at a 1:6w/v ratio (solid:liquid) and 200rpm. The solids obtained under the selected autohydrolysis conditions were subjected to enzymatic hydrolysis with a commercial cellulase cocktail, and the enzymatic hydrolysate was fermented using Saccharomyces cerevisiae. The results obtained from the pretreatment process showed that the glucan content in the pretreated solid was mostly preserved, and an increase in the digestibility was observed for the case with a SF of 4.13 (190°C, 30min). Enzymatic hydrolysis of the pretreated solids showed a yield of 74.3%, with a glucose concentration of 126g/L, resulting in 65.26g/L of ethanol after 10h of fermentation, which represent a 98.4% conversion according to the theoretical ethanol yield value. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Biosorption of heavy metals by pretreated biomass of aspergillus niger

    International Nuclear Information System (INIS)

    Javaid, A.; Bajwa, R.; Manzoor, T.

    2011-01-01

    The present study reports the bio sorption potential of chemically pretreated mycelial biomass of fungus Aspergillus niger van. Tieghem for Cu(II) and Ni(II) ions from aqueous phase. Fungal biomass was pretreated with different types of alkaline/salts (NaOH, NaHCO/sub 3/, Na/sub 2/CO/sub 3/, NaCl and CaCl/sub 2/), acids (HCl and H/sub 2/SO/sub 4/) and detergent. Pretreatment of biomass with Na/sub 2/CO/sub 3/ and NaOH were proved to increase or maintain adsorption efficiency and capacity in comparison to untreated biomass. Pretreatment with NaHCO/sub 3/, detergent, NaCl and CaCl/sub 2/ significantly reduce (10-40%) metal sequestering efficiency of the adsorbent. Whereas, acid treatments resulted in drastic loss (80%) in metal uptake efficiency of the biomass. Amongst various pretreatments, Na/sub 2/CO/sub 3/ could be use efficiently for the removal of Ni(II) and Cu(II) ions from aqueous solution using A. niger. (author)

  7. 1-Butyl-3-Methylimidazolium Chloride Pretreatment on Malaysia Lignocellulose Wastes

    International Nuclear Information System (INIS)

    Lee, L.P.; Nur Hasyareeda Hassan; Muhammad Rahimi Yusop

    2015-01-01

    Ionic liquids (ILs) are of great interest as potential solvents for the production of fuels from lignocellulose biomass which is a potential source of bio fuels. To study the effects of pretreatment, 1-butyl-3-methylimidazolium chloride ([B mim]Cl) was used to pretreat woody plants, kempas (Koompassia malaccensis) and jelutong (Dyera costulata), and non-woody plants, kenaf (Hibiscus cannabinus) and rice husk (Oryza sativa) at 120 degree Celsius for 24 h. Cellulose was regenerated by the addition of water. The cell wall composition and structure of the lignocellulose bio masses before and after the ILs pretreatment were observed and characterized using field emission scanning electron microscopy (FESEM), attenuated total reflectance fourier transform infrared (ATR FT-IR) spectroscopy, and X-ray diffraction (XRD). After the pretreatment, enzymatic hydrolysis was carried out to identify the total reducing sugars (TRS) yields using dinitrosalicylic acid (DNS) method. Regenerated lignocellulose bio masses resulted in high TRS yields compared to their counter-parts which are in agreement with the findings of FESEM, ATR FT-IR and XRD that exhibited regenerated cellulose were less crystalline and more amorphous upon IL pretreatment. Therefore, kempas and jelutong can be alternate sources for the bio fuels production. (author)

  8. Cellulase digestibility of pretreated biomass is limited by cellulose accessibility.

    Science.gov (United States)

    Jeoh, Tina; Ishizawa, Claudia I; Davis, Mark F; Himmel, Michael E; Adney, William S; Johnson, David K

    2007-09-01

    Attempts to correlate the physical and chemical properties of biomass to its susceptibility to enzyme digestion are often inconclusive or contradictory depending on variables such as the type of substrate, the pretreatment conditions and measurement techniques. In this study, we present a direct method for measuring the key factors governing cellulose digestibility in a biomass sample by directly probing cellulase binding and activity using a purified cellobiohydrolase (Cel7A) from Trichoderma reesei. Fluorescence-labeled T. reesei Cel7A was used to assay pretreated corn stover samples and pure cellulosic substrates to identify barriers to accessibility by this important component of cellulase preparations. The results showed cellulose conversion improved when T. reesei Cel7A bound in higher concentrations, indicating that the enzyme had greater access to the substrate. Factors such as the pretreatment severity, drying after pretreatment, and cellulose crystallinity were found to directly impact enzyme accessibility. This study provides direct evidence to support the notion that the best pretreatment schemes for rendering biomass more digestible to cellobiohydrolase enzymes are those that improve access to the cellulose in biomass cell walls, as well as those able to reduce the crystallinity of cell wall cellulose.

  9. Intensification of biogas production using pretreatment based on hydrodynamic cavitation.

    Science.gov (United States)

    Patil, Pankaj N; Gogate, Parag R; Csoka, Levente; Dregelyi-Kiss, Agota; Horvath, Miklos

    2016-05-01

    The present work investigates the application of hydrodynamic cavitation (HC) for the pretreatment of wheat straw with an objective of enhancing the biogas production. The hydrodynamic cavitation reactor is based on a stator and rotor assembly. The effect of three different speeds of rotor (2300, 2500, 2700 rpm), wheat straw to water ratios (0.5%, 1% and 1.5% wt/wt) and also treatment times as 2, 4 and 6 min have been investigated in the work using the design of experiments (DOE) approach. It was observed that the methane yield of 31.8 ml was obtained with untreated wheat straw whereas 77.9 ml was obtained with HC pre-treated wheat straw confirming the favourable changes during the pre-treatment. The combined pre-treatment using KOH and HC gave maximum yield of biogas as 172.3 ml. Overall, it has been established that significant enhancement in the biogas production can be obtained due to the pretreatment using HC which can also be further intensified by combination with chemical treatment. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. ALA Pretreatment Improves Waterlogging Tolerance of Fig Plants.

    Directory of Open Access Journals (Sweden)

    Yuyan An

    Full Text Available 5-aminolevulinic acid (ALA, a natural and environmentally friendly plant growth regulator, can improve plant tolerance to various environmental stresses. However, whether ALA can improve plant waterlogging tolerance is unknown. Here, we investigated the effects of ALA pretreatment on the waterlogging-induced damage of fig (Ficus carica Linn. plants, which often suffer from waterlogging stress. ALA pretreatment significantly alleviated stress-induced morphological damage, increased leaf relative water content (RWC, and reduced leaf superoxide anion ([Formula: see text] production rate and malonaldehyde (MDA content in fig leaves, indicating ALA mitigates waterlogging stress of fig plants. We further demonstrated that ALA pretreatment largely promoted leaf chlorophyll content, photosynthetic electron transfer ability, and photosynthetic performance index, indicating ALA significantly improves plant photosynthetic efficiency under waterlogging stress. Moreover, ALA pretreatment significantly increased activities of leaf superoxide dismutase (SOD and peroxidase (POD, root vigor, and activities of root alcohol dehydrogenase (ADH, and lactate dehydrogenase (LDH, indicating ALA also significantly improves antioxidant ability and root function of fig plants under waterlogging stress. Taken together, ALA pretreatment improves waterlogging tolerance of fig plants significantly, and the promoted root respiration, leaf photosynthesis, and antioxidant ability may contribute greatly to this improvement. Our data firstly shows that ALA can improve plant waterlogging tolerance.

  11. Enhancing biogas production of corn stover by fast pyrolysis pretreatment.

    Science.gov (United States)

    Wang, Fang; Zhang, Deli; Wu, Houkai; Yi, Weiming; Fu, Peng; Li, Yongjun; Li, Zhihe

    2016-10-01

    A new thermo-chemical pretreatment by a lower temperature fast pyrolysis (LTFP) was applied to promote anaerobic digestion (AD) efficiency of corn stover (CS). The pretreatment experiment was performed by a fluidized bed pyrolysis reactor at 180, 200 and 220°C with a carrier gas flow rate of 4 and 3m(3)/h. The components characteristics, Scanning Electron Microscope (SEM) images and Crystal Intensity (CrI) of the pretreated CS were tested to explore effectiveness of the pretreatment. The results showed that the cumulative methane production at 180°C for 4 and 3m(3)/h were 199.8 and 200.3mL/g TS, respectively. As compared to the untreated CS, the LTFP pretreatment significantly (a<0.05) increased the methane production by 18.07% and 18.33%, respectively. Methane production was well fitted by the Gompertz models, and the maximum methane potential and AD efficiency was obtained at 180°C for 3m(3)/h. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Pretreatment of macroalgae for volatile fatty acid production.

    Science.gov (United States)

    Pham, Thi Nhan; Um, Youngsoon; Yoon, Hyon Hee

    2013-10-01

    In this study, a novel method was proposed for the biological pretreatment of macroalgae (Laminaria japonica, Pachymeniopsis elliptica, and Enteromorpha crinita) for production of volatile fatty acid (VFA) by anaerobic fermentation. The amount of VFA produced from 40 g/L of L. japonica increased from 8.3 g/L (control) to 15.6 g/L when it was biologically pretreated with Vibrio harveyi. The biological treatment of L. japonica with Vibrio spp. was most effective likely due to the alginate lyase activity of Vibrio spp. However, a considerable effect was also observed after biological pretreatment of P. elliptica and E. crinita, which are red and green algae, respectively. Alkaline pretreatment of 40 g/L of L. japonica with 0.5 N NaOH resulted in an increase of VFA production to 12.2 g/L. These results indicate that VFA production from macroalgae can be significantly enhanced using the proposed biological pretreatments. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. Effect of pretreating of host oil on coprocessing

    Energy Technology Data Exchange (ETDEWEB)

    Hajdu, P.E.; Tierney, J.W.; Wender, I. [Univ. of Pittsburgh, PA (United States)

    1995-12-31

    The principal objective of this research was to determine if coprocessing performance (i.e., coal conversion and oil yield) could be significantly improved by pretreating the heavy resid prior to reacting it with coal. For this purpose, two petroleum vacuum resids (1000{degrees}F+), one from the Amoco Co. and another from the Citgo Co., were used as such and after they had been pretreated by catalytic hydrogenation and hydrocracking reactions. The pretreatments were aimed at improving the host oil by; (1) converting any aromatic structures in the petroleum to hydroaromatic compounds capable of donating hydrogen, (2) cracking the heavy oil to lower molecular weight material that might serve as a better solvent, (3) reducing the coking propensity of the heavy oil through the hydrogenation of polynuclear aromatic compounds, and (4) removing metals and heteroatoms that might poison a coprocessing catalyst. Highly dispersed catalysts, including fine particle Fe- and Mo-based, and dicobalt octacarbonyl, Co{sub 2}(CO){sub 8}, were used in this study. The untreated and pretreated resids were extensively characterized in order to determine chemical changes brought about by the pretreatments. The modified heavy oils were then coprocessed with an Illinois No. 6 coal as well as with a Wyodak coal, and compared to coprocessing with untreated resids under the same hydroliquefaction conditions. The amount of oil derived from coal was estimated by measuring the level of phenolic oxygen (derived mainly from coal) present in the oil products. Results are presented and discussed.

  14. Activation of glassy carbon electrodes by photocatalytic pretreatment

    Energy Technology Data Exchange (ETDEWEB)

    Dumanli, Onur [Department of Chemistry, Faculty of Science and Art, Ondokuz Mayis University, Kurupelit, 55139 Samsun (Turkey); Onar, A. Nur [Department of Chemistry, Faculty of Science and Art, Ondokuz Mayis University, Kurupelit, 55139 Samsun (Turkey)], E-mail: nonar@omu.edu.tr

    2009-11-01

    This paper describes a simple and rapid photocatalytic pretreatment procedure that removes contaminants from glassy carbon (GC) surfaces. The effectiveness of TiO{sub 2} mediated photocatalytic pretreatment procedure was compared to commonly used alumina polishing procedure. Cyclic voltammetric and chronocoulometric measurements were carried out to assess the changes in electrode reactivity by using four redox systems. Electrochemical measurements obtained on photocatalytically treated GC electrodes showed a more active surface relative to polished GC. In cyclic voltammograms of epinephrine, Fe(CN){sub 6}{sup 3-/4-} and ferrocene redox systems, higher oxidation and reduction currents were observed. The heterogeneous electron transfer rate constants (k{sup o}) were calculated for Fe(CN){sub 6}{sup 3-/4-} and ferrocene which were greater for photocatalytic pretreatment. Chronocoulometry was performed in order to find the amount of adsorbed methylene blue onto the electrode and was calculated as 0.34 pmol cm{sup -2} for photocatalytically pretreated GC. The proposed photocatalytic GC electrode cleansing and activating pretreatment procedure was more effective than classical alumina polishing.

  15. Radiation protection

    International Nuclear Information System (INIS)

    1989-01-01

    A NRPB leaflet in the 'At-a-Glance' series explains in a simple but scientifically accurate way what radiation is, the biological effects and the relative sensitivity of different parts of the human body. The leaflet then discusses radiation protection principles, radiation protection in the UK and finally the effectiveness of this radiation protection as judged by a breakdown of the total dose received by an average person in the UK, a heavy consumer of Cumbrian seafood, an average nuclear industry worker and an average person in Cornwall. (UK)

  16. The use of raw and acid-pretreated bivalve mollusk shells to remove metals from aqueous solutions

    International Nuclear Information System (INIS)

    Liu Yang; Sun Changbin; Xu Jin; Li Youzhi

    2009-01-01

    Heavy metal removal from industrial wastewater is not only to protect living organisms in the environment but also to conserve resources such as metals and water by enabling their reuse. To overcome the disadvantage of high cost and secondary pollution by the conventional physico-chemical treatment techniques, environmentally benign and low-cost adsorbents are in demand. In this study, the use of raw and acid-pretreated bivalve mollusk shells (BMSs) to remove metals from aqueous solutions with single or mixed metal was evaluated at different BMSs doses, pH and temperatures in batch shaking experiments in laboratory conditions. When the BMSs were used to treat CuSO 4 .5H 2 O solution, the copper sorption capacities of the raw and acid-pretreated BMSs were approximately 38.93 mg/g and 138.95 mg/g, respectively. The copper removal efficiency (CRE) of the raw BMSs became greatly enhanced with increasing initial pH, reaching 99.51% at the initial pH 5. Conversely, the CRE of the acid-pretreated BMSs was maintained at 99.48-99.52% throughout the pH range of 1-5. Furthermore, the CRE values of the raw and acid-pretreated BMSs were not greatly changed when the temperature was varied from 15 deg. C to 40 deg. C. In addition, the CRE value of the raw BMSs was maintained for 12 cycles of sorption-desorption with a CRE of 98.4% being observed in the final cycle. Finally, when the BMSs were used to treat electroplating wastewater, the removal efficiencies (REs) of the raw BMSs were 99.97%, 98.99% and 87% for Fe, Zn and Cu, respectively, whereas the REs of the acid-pretreated BMSs were 99.98%, 99.43% and 92.13%, respectively. Ion exchange experiments revealed that one of mechanisms for metal sorption by the BMSs from aqueous solution is related to ion exchange, especially between the metal ions in the treated solution and Ca 2+ from BMSs. Infrared absorbance spectra analysis indicated that the acid pretreatment led to occurrence of the groups (i.e. -OH, -NH, C=O and S=O) of

  17. The use of raw and acid-pretreated bivalve mollusk shells to remove metals from aqueous solutions.

    Science.gov (United States)

    Liu, Yang; Sun, Changbin; Xu, Jin; Li, Youzhi

    2009-08-30

    Heavy metal removal from industrial wastewater is not only to protect living organisms in the environment but also to conserve resources such as metals and water by enabling their reuse. To overcome the disadvantage of high cost and secondary pollution by the conventional physico-chemical treatment techniques, environmentally benign and low-cost adsorbents are in demand. In this study, the use of raw and acid-pretreated bivalve mollusk shells (BMSs) to remove metals from aqueous solutions with single or mixed metal was evaluated at different BMSs doses, pH and temperatures in batch shaking experiments in laboratory conditions. When the BMSs were used to treat CuSO(4)x5H(2)O solution, the copper sorption capacities of the raw and acid-pretreated BMSs were approximately 38.93 mg/g and 138.95 mg/g, respectively. The copper removal efficiency (CRE) of the raw BMSs became greatly enhanced with increasing initial pH, reaching 99.51% at the initial pH 5. Conversely, the CRE of the acid-pretreated BMSs was maintained at 99.48-99.52% throughout the pH range of 1-5. Furthermore, the CRE values of the raw and acid-pretreated BMSs were not greatly changed when the temperature was varied from 15 degrees C to 40 degrees C. In addition, the CRE value of the raw BMSs was maintained for 12 cycles of sorption-desorption with a CRE of 98.4% being observed in the final cycle. Finally, when the BMSs were used to treat electroplating wastewater, the removal efficiencies (REs) of the raw BMSs were 99.97%, 98.99% and 87% for Fe, Zn and Cu, respectively, whereas the REs of the acid-pretreated BMSs were 99.98%, 99.43% and 92.13%, respectively. Ion exchange experiments revealed that one of mechanisms for metal sorption by the BMSs from aqueous solution is related to ion exchange, especially between the metal ions in the treated solution and Ca(2+) from BMSs. Infrared absorbance spectra analysis indicated that the acid pretreatment led to occurrence of the groups (i.e. -OH, -NH, C=O and S

  18. Cisplatin toxicity reduced in human cultured renal tubular cells by oxygen pretreatment.

    Science.gov (United States)

    Kaeidi, Ayat; Rasoulian, Bahram; Hajializadeh, Zahra; Pourkhodadad, Soheila; Rezaei, Maryam

    2013-01-01

    Cisplatin is an effective and widely used chemotherapy agent and its side effects, particularly nephrotoxicity, limit its usage and related platinum-based drugs. Cisplatin nephrotoxicity is mainly due to extremely increase in reactive oxygen species (ROS) generation leading to kidney tubular cell death. Preconditioning with oxidative stress has been demonstrated to stimulate the cellular adaptation to subsequent severe oxidative stress. Short term oxygen pre-exposure as a mild oxidative stress may enhance some endogenous defense mechanisms, so its effect on Cisplatin induced cell death was investigated in present research. We studied the effects of hyperoxic environment pre-exposure on Cisplatin toxicity in an in-vitro model of cultured human embryonic tubular epithelial cells (AD293). Viability of AD293 cells, as evaluated by MTT-assay, was affected by Cisplatin in a time (1-4 h) dependent model. Biochemical markers of cell apoptosis were evaluated using immunoblotting. Pretreatment with nearly pure oxygen (≥90%) for 2 h significantly reduced the level of cell damage. Activated caspase 3 and Bax/Bcl-2 ratio were significantly increased in Cisplatin-treated cells. Oxygen pretreatment inhibited caspase 3 activation and decreased Bax/Bcl-2 ratio. Oxygen pre-treatment itself not showed any cytotoxicity in exposure times up to 3 h. Our data indicate that hyperoxic preconditioning reduces Cisplatin toxicity in cultured human tubular epithelial cells. The exact mechanism of protection is unclear, though enhancement of some endogenous defense mechanisms and subsequently scavenging of free oxygen radicals may play an important role.

  19. Effect of isoproturon pretreatment on the biochemical toxicodynamics of anilofos in male rats.

    Science.gov (United States)

    Hazarika, A; Sarkar, S N

    2001-08-28

    Anilofos and isoproturon are important herbicides of organophosphorus and substituted phenylurea groups, respectively. Isoproturon is an inducer of hepatic drug-metabolizing enzymes. Animals and humans have the potential to be exposed to the mixture of these intentionally introduced environmental xenobiotics, but toxicological interactions between these herbicides are not known. Effects of isoproturon pretreatment (675 mg/kg/day for 3 consecutive days) on the toxic actions of anilofos administered orally as a single dose (850 mg/kg) were evaluated by determining some biochemical attributes in blood (erythrocyte/plasma), brain and liver of rats. Anilofos or isoproturon alone or in combination failed to produce any noticeable signs of cholinergic hyperactivity and behavioural alterations. Isoproturon did not potentiate the anticholinesterase action of anilofos in blood and liver. Inhibition of brain acetylcholinesterase was significantly protected. No significant alteration in anilofos-mediated production of lipid peroxidation was observed in erythrocyte and brain of isoproturon-pretreated rats, but it was significantly increased in liver. Anilofos did not affect GSH and GST. The isoproturon-mediated increase in GSH levels of brain (threefold) and liver (3.6-fold) was also not affected following combined administration. GST activity was increased in liver of rats given isoproturon alone (fourfold) or in combination with anilofos (2.8-fold). Activities of total ATPase, Mg2+-ATPase and Na+-K+-ATPase were not affected in rats given either anilofos alone or herbicides in sequence. With these treatments, there were no alterations in the protein content of plasma, brain and liver. Overall findings of the study indicate that isoproturon pretreatment does not alter the toxicity of anilofos, the GSH-GST metabolic pathway may not have a significant implication in the detoxification of anilofos and the production of a reactive oxygen species may be a factor in mediating

  20. Protected Areas

    Data.gov (United States)

    Kansas Data Access and Support Center — This dataset shows the boundaries of properties in Kansas in public or institutional ownership that contain ecological resources that merit some level of protection....

  1. Protective clothing

    International Nuclear Information System (INIS)

    Malet, J.C.; Regnier, J.

    1979-01-01

    The present operational and intervention suits are described. Research work is currently in progress to improve the performance of the existing suits and to develop more resistant protective clothing. (author)

  2. Radiation protection

    International Nuclear Information System (INIS)

    Ures Pantazi, M.

    1994-01-01

    This work define procedures and controls about ionizing radiations. Between some definitions it found the following topics: radiation dose, risk, biological effects, international radioprotection bodies, workers exposure, accidental exposure, emergencies and radiation protection

  3. Employment protection

    OpenAIRE

    Stefano Scarpetta

    2014-01-01

    Laws on hiring and firing are intended to protect workers from unfair behavior by employers, to counter imperfections in financial markets that limit workers’ ability to insure themselves against job loss, and to preserve firm-specific human capital. But by imposing costs on firms’ adaptation to changes in demand and technology, employment protection legislation may reduce not only job destruction but also job creation, hindering the efficient allocation of labor and productivity growth....

  4. Environmental protection

    International Nuclear Information System (INIS)

    Martinez, A.S.

    1987-01-01

    The question of environment protection related to the use of nuclear energy aiming to power generation, based on the harmonic concept of economic and industrial development, preserving the environment, is discussed. A brief study of environmental impacts for some energy sources, including nuclear energy, to present the systems of a nuclear power plant which aim at environmental protection, is done. (M.C.K.) [pt

  5. Radiation protection

    International Nuclear Information System (INIS)

    Koelzer, W.

    1976-01-01

    The lecture is divided into five sections. The introduction deals with the physical and radiological terms, quantities and units. Then the basic principles of radiological protection are discussed. In the third section attention is paid to the biological effects of ionizing radiation. The fourth section deals with the objectives of practical radiological protection. Finally the emergency measures are discussed to be taken in radiation accidents. (HP) [de

  6. Copyright protection

    OpenAIRE

    Plchotová, Gabriela

    2011-01-01

    The aim of this thesis is to offer a straightforward manual to anyone who authors their own original work or who utilises the original work of other creators. As such, it is necessary to briefly and clearly explain the historical development and essential terms of authorship as a concept and the origin of the need for copyright protection. Furthermore, this thesis includes chapters on copyright protection development specifically in the Czech Republic and the current definition of related law...

  7. Chemical and Physicochemical Pretreatment of Lignocellulosic Biomass: A Review

    Directory of Open Access Journals (Sweden)

    Gary Brodeur

    2011-01-01

    Full Text Available Overcoming the recalcitrance (resistance of plant cell walls to deconstruction of lignocellulosic biomass is a key step in the production of fuels and chemicals. The recalcitrance is due to the highly crystalline structure of cellulose which is embedded in a matrix of polymers-lignin and hemicellulose. The main goal of pretreatment is to overcome this recalcitrance, to separate the cellulose from the matrix polymers, and to make it more accessible for enzymatic hydrolysis. Reports have shown that pretreatment can improve sugar yields to higher than 90% theoretical yield for biomass such as wood, grasses, and corn. This paper reviews different leading pretreatment technologies along with their latest developments and highlights their advantages and disadvantages with respect to subsequent hydrolysis and fermentation. The effects of different technologies on the components of biomass (cellulose, hemicellulose, and lignin are also reviewed with a focus on how the treatment greatly enhances enzymatic cellulose digestibility.

  8. Chemical and physicochemical pretreatment of lignocellulosic biomass: a review.

    Science.gov (United States)

    Brodeur, Gary; Yau, Elizabeth; Badal, Kimberly; Collier, John; Ramachandran, K B; Ramakrishnan, Subramanian

    2011-01-01

    Overcoming the recalcitrance (resistance of plant cell walls to deconstruction) of lignocellulosic biomass is a key step in the production of fuels and chemicals. The recalcitrance is due to the highly crystalline structure of cellulose which is embedded in a matrix of polymers-lignin and hemicellulose. The main goal of pretreatment is to overcome this recalcitrance, to separate the cellulose from the matrix polymers, and to make it more accessible for enzymatic hydrolysis. Reports have shown that pretreatment can improve sugar yields to higher than 90% theoretical yield for biomass such as wood, grasses, and corn. This paper reviews different leading pretreatment technologies along with their latest developments and highlights their advantages and disadvantages with respect to subsequent hydrolysis and fermentation. The effects of different technologies on the components of biomass (cellulose, hemicellulose, and lignin) are also reviewed with a focus on how the treatment greatly enhances enzymatic cellulose digestibility.

  9. Fluid mechanics relevant to flow through pretreatment of cellulosic biomass.

    Science.gov (United States)

    Archambault-Léger, Véronique; Lynd, Lee R

    2014-04-01

    The present study investigates fluid mechanical properties of cellulosic feedstocks relevant to flow through (FT) pretreatment for biological conversion of cellulosic biomass. The results inform identifying conditions for which FT pretreatment can be implemented in a practical context. Measurements of pressure drop across packed beds, viscous compaction and water absorption are reported for milled and not milled sugarcane bagasse, switchgrass and poplar, and important factors impacting viscous flow are deduced. Using biomass knife-milled to pass through a 2mm sieve, the observed pressure drop was highest for bagasse, intermediate for switchgrass and lowest for poplar. The highest pressure drop was associated with the presence of more fine particles, greater viscous compaction and the degree of water absorption. Using bagasse without particle size reduction, the instability of the reactor during pretreatment above 140kg/m(3) sets an upper bound on the allowable concentration for continuous stable flow. Copyright © 2014. Published by Elsevier Ltd.

  10. Leachate pretreatment for enhancing organic matter conversion in landfill bioreactor

    International Nuclear Information System (INIS)

    He Pinjing; Qu Xian; Shao Liming; Li Guojian; Lee Duujong

    2007-01-01

    Direct recycling of leachate from refuse of high food waste content was shown to ineffectively stabilize the refuse. This work aims at evaluating the effects of three pretreatments of leachate on the refuse stabilization efficiency were investigated. Pretreatment of leachate using an anaerobic upflow filtration bioreactor (UFB) or a well-decomposed waste layer could reduce the COD and provide methanogens, both were beneficial to establish early methanogenesis status. Using an aerobic sequential batch reactor (SBR) to pretreat the leachate could reduce its COD to 1000 mg l -1 , but the fully developed methanogenesis phase would be built up in a later stage. The organic matters in the effluent leachate inhibited both the hydrolysis/acidogenesis and the methanogenesis steps in the refuse. With the dilution and acid neutralization effects by the recycled leachate, a favorable methanogenetic environment could be produced from the column's top, which moved downward along, and finally made the breakthrough of the column

  11. Hazard Analysis for the Pretreatment Engineering Platform (PEP)

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan, Robin S.; Geeting, John GH; Lawrence, Wesley E.; Young, Jonathan

    2008-07-10

    The Pretreatment Engineering Platform (PEP) is designed to perform a demonstration on an engineering scale to confirm the Hanford Waste Treatment Plant Pretreatment Facility (PTF) leaching and filtration process equipment design and sludge treatment process. The system will use scaled prototypic equipment to demonstrate sludge water wash, caustic leaching, oxidative leaching, and filtration. Unit operations to be tested include pumping, solids washing, chemical reagent addition and blending, heating, cooling, leaching, filtration, and filter cleaning. In addition, the PEP will evaluate potential design changes to the ultrafiltration process system equipment to potentially enhance leaching and filtration performance as well as overall pretreatment throughput. The skid-mounted system will be installed and operated in the Processing Development Laboratory-West at Pacific Northwest National Laboratory (PNNL) in Richland, Washington.

  12. Carbohydrate degradation mechanisms and compounds from pretreated biomass

    DEFF Research Database (Denmark)

    Rasmussen, Helena

    The formation of inhibitors during pretreatment of lignocellulosic feedstocks is a persistent problem, and notably the compounds that retard enzymatic cellulose conversion represent an obstacle for achieving optimal enzymatic productivity and high glucose yields. Compounds with many chemical...... pretreated wheat straw after enzymatic treatment. It was found that formation of the oligophenolic degradation compounds were common across biomass sources as sugar cane bagasse and oil palm empty fruit bunches. These findings were in line with that the oligophenolic compounds arise from reactions involving...... functionalities are formed during biomass pretreatment, which gives possibilities for various chemical reactions to take place and hence formation of many new potential inhibitor compounds. This somehow overlooked contemplation formed the basis for the main hypothesis investigated in this work: Hypothesis 1...

  13. Urine pretreatment for waste water processing systems. [for space station

    Science.gov (United States)

    Winkler, H. E.; Verostko, C. E.; Dehner, G. F.

    1983-01-01

    Recovery of high quality water from urine is an essential part of life support on a Space Station to avoid costly launch and resupply penalties. Water can be effectively recovered from urine by distillation following pretreatment by a chemical agent to inhibit microorganism contamination and fix volatile ammonia constituents. This paper presents the results of laboratory investigations of several pretreatment chemicals which were tested at several concentration levels in combination with sulfuric acid in urine. The optimum pretreatment formulation was then evaluated with urine in the Hamilton Standard Thermoelectric Integrated Membrane Evaporation Subsystem (TIMES). Over 2600 hours of test time was accumulated. Results of these laboratory and system tests are presented in this paper.

  14. Wet oxidation pretreatment of rape straw for ethanol production

    DEFF Research Database (Denmark)

    Arvaniti, Efthalia; Bjerre, Anne Belinda; Schmidt, Jens Ejbye

    2012-01-01

    Rape straw can be used for production of second generation bioethanol. In this paper we optimized the pretreatment of rape straw for this purpose using Wet oxidation (WO). The effect of reaction temperature, reaction time, and oxygen gas pressure was investigated for maximum ethanol yield via...... Simultaneous Saccharification and Fermentation (SSF). To reduce the water use and increase the energy efficiency in WO pretreatment features like recycling liquid (filtrate), presoaking of rape straw in water or recycled filtrate before WO, skip washing pretreated solids (filter cake) after WO, or use of whole...... gas produced higher ethanol yields and cellulose, hemicelluloses, and lignin recoveries, than 15 min WO treatment at 195 °C. Also, recycling filtrate and use of higher oxygen gas pressure reduced recovery of materials. The use of filtrate could be inhibitory for the yeast, but also reduced lactic acid...

  15. A xylanase-aided enzymatic pretreatment facilitates cellulose nanofibrillation.

    Science.gov (United States)

    Long, Lingfeng; Tian, Dong; Hu, Jinguang; Wang, Fei; Saddler, Jack

    2017-11-01

    Although biological pretreatment of cellulosic fiber based on endoglucanases has shown some promise to facilitate cellulose nanofibrillation, its efficacy is still limited. In this study, a xylanase-aided endoglucanase pretreatment was assessed on the bleached hardwood and softwood Kraft pulps to facilitate the downstream cellulose nanofibrillation. Four commercial xylanase preparations were compared and the changes of major fiber physicochemical characteristics such as cellulose/hemicellulose content, gross fiber properties, fiber morphologies, cellulose accessibility/degree of polymerization (DP)/crystallinity were systematically evaluated before and after enzymatic pretreatment. It showed that the synergistic cooperation between endoglucanase and certain xylanase (Biobrite) could efficiently "open up" the hardwood Kraft pulp with limited carbohydrates degradation (cellulose nanofibrillation during mild sonication process (90Wh) with more uniform disintegrated nanofibril products (50-150nm, as assessed by scanning electron microscopy and UV-vis spectroscopy). Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Radiological protection

    International Nuclear Information System (INIS)

    Azorin N, J.; Azorin V, J. C.

    2010-01-01

    This work is directed to all those people related with the exercise of the radiological protection and has the purpose of providing them a base of knowledge in this discipline so that they can make decisions documented on technical and scientist factors for the protection of the personnel occupationally exposed, the people in general and the environment during the work with ionizing radiations. Before de lack of a text on this matter, this work seeks to cover the specific necessities of our country, providing a solid presentation of the radiological protection, included the bases of the radiations physics, the detection and radiation dosimetry, the radiobiology, the normative and operational procedures associates, the radioactive wastes, the emergencies and the transport of the radioactive material through the medical and industrial applications of the radiations, making emphasis in the relative particular aspects to the radiological protection in Mexico. The book have 16 chapters and with the purpose of supplementing the given information, are included at the end four appendixes: 1) the radioactive waste management in Mexico, 2-3) the Mexican official standards related with the radiological protection, 4) a terms glossary used in radiological protection. We hope this book will be of utility for those people that work in the investigation and the applications of the ionizing radiations. (Author)

  17. Fungal pretreatment of straw for enhanced biogas yield

    Energy Technology Data Exchange (ETDEWEB)

    Feng, Xinmei; Pilar Castillo, Maria del; Schnuerer, Anna

    2013-07-01

    Among lignocellulosic materials from the agricultural sector, straw is considered to have the biggest potential as a biofuel and therefore also represents a big potential for biogas production. However, the degradation of lignocellulosic materials is somewhat restricted due to the high content of lignin that binds cellulose and hemicellulose and makes them unavailable for microbial degradation. Consequently, low methane yields are achieved. The biodegradability of the lignocellulosic material can be increased by a pretreatment. Optimally the pre-treatment should give an increase in the formation of sugars while avoiding the degradation or loss of carbohydrates and the formation of inhibitory by-products. The treatment should also be cost-effective. Different methods for pre-treatment of lignocellulosic material have been explored, for example thermal, acid, alkaline and oxidative pretreatments. However, they often have a high energy demand. Biological treatment with fungi represents an alternative method for pretreatment of lignocellulosic materials that could be comparably more environmentally friendly, easier to operate and with low energy input. The fungal groups of interest for lignocellulose degradation are the wood decaying fungi, such as the white-, brown-rot and cellulose degraders. The purpose with this work was to increase the biogas potential of straw by using a pretreatment with fungi. Straw was incubated with fungi at aerobic conditions under certain periods of time. The growth and colonization of the straw by the fungi was expected to increase the availability of the lignocellulosic structure of the straw and thus positively affect the biogas potential. In addition also, the spent lignocellulosic material from the cultivation of edible fungi was investigated. We hypothesized that also growth of edible fungi could give a more accessible material and thus give higher biogas potential compared to the substrate before fungal growth.

  18. Pre-treating Seed to Enhance Germination of Desert Shrubs

    Energy Technology Data Exchange (ETDEWEB)

    W. K. Ostler; D. C. Anderson; D. J. Hansen

    2002-06-01

    Creosotebush [Larrea tridentata (D.C.) Cav.] and white bursage [Ambrosia dumosa (A. Gray) W.W. Payne] seeds were subjected to pre-treatments of rinsing and soaking in water and thiourea to enhance germination in laboratory experiments. The effects of darkness, temperature, seed source, and soil moisture were also evaluated in the laboratory. The best pre-treatment from the laboratory experiments, rinsing with water for 36 hours followed by drying, was field-tested at Fort Irwin, California. Two sites and two seeding dates (early March and mid April) were determined for each site. Five mulch treatments (no mulch, straw, gravel, chemical stabilizer, and plastic) were evaluated in combination with the seed pre-treatments. Field emergence was greatly enhanced with the seed pre-treatment for white bursage during the March (18-42% increase in germination) and April seedings (16-23% increase in germination). Creosotebush showed poor germination during March (2-5%) when soil temperatures averaged 15 C, but germination increased during the April trials (6-43%) when soil temperatures averaged 23 C. The seed pre-treatment during the April trials increased germination from 16-23%. The plastic mulch treatment increased germination dramatically during both the March and April trials. The plastic mulch increased soil temperatures (8-10 C)and maintained high humidity during germination. Both the chemical stabilizer and the gravel mulches improved germination over the control while the straw mulch decreased germination. These results suggest that seed pre-treatments combined with irrigation and mulch are effective techniques to establish these two dominant Mojave Desert species from seed.

  19. Deep Eutectic Solvents pretreatment of agro-industrial food waste.

    Science.gov (United States)

    Procentese, Alessandra; Raganati, Francesca; Olivieri, Giuseppe; Russo, Maria Elena; Rehmann, Lars; Marzocchella, Antonio

    2018-01-01

    Waste biomass from agro-food industries are a reliable and readily exploitable resource. From the circular economy point of view, direct residues from these industries exploited for production of fuel/chemicals is a winning issue, because it reduces the environmental/cost impact and improves the eco-sustainability of productions. The present paper reports recent results of deep eutectic solvent (DES) pretreatment on a selected group of the agro-industrial food wastes (AFWs) produced in Europe. In particular, apple residues, potato peels, coffee silverskin, and brewer's spent grains were pretreated with two DESs, (choline chloride-glycerol and choline chloride-ethylene glycol) for fermentable sugar production. Pretreated biomass was enzymatic digested by commercial enzymes to produce fermentable sugars. Operating conditions of the DES pretreatment were changed in wide intervals. The solid to solvent ratio ranged between 1:8 and 1:32, and the temperature between 60 and 150 °C. The DES reaction time was set at 3 h. Optimal operating conditions were: 3 h pretreatment with choline chloride-glycerol at 1:16 biomass to solvent ratio and 115 °C. Moreover, to assess the expected European amount of fermentable sugars from the investigated AFWs, a market analysis was carried out. The overall sugar production was about 217 kt yr -1 , whose main fraction was from the hydrolysis of BSGs pretreated with choline chloride-glycerol DES at the optimal conditions. The reported results boost deep investigation on lignocellulosic biomass using DES. This investigated new class of solvents is easy to prepare, biodegradable and cheaper than ionic liquid. Moreover, they reported good results in terms of sugars' release at mild operating conditions (time, temperature and pressure).

  20. Bioethanol production: Pretreatment and enzymatic hydrolysis of softwood

    Energy Technology Data Exchange (ETDEWEB)

    Tengborg, Charlotte

    2000-05-01

    The enzymatic hydrolysis process can be used to produce bioethanol from softwood, which are the dominating raw material in the Northern hemisphere. This thesis deals with the development of the process focusing on the pretreatment and the enzymatic hydrolysis stages. The influence of pretreatment conditions on sugar yield, and the effect of inhibitors on the ethanol yield, were investigated for spruce and pine. The maximum yields of hemicellulose sugars and glucose were obtained under different pretreatment conditions. This indicates that two-stage pretreatment may be preferable. The added catalysts, H{sub 2}SO{sub 4} and SO{sub 2}, resulted in similar total sugar yields about 40 g/100 g dry raw material. However, the fermentability of SO{sub 2}-impregnated material was better. This pretreatment resulted in the formation of inhibitors to the subsequent process steps, e.g. sugar and lignin degradation products. The glucose yield in the enzymatic hydrolysis stage was affected by various parameters such as enzyme loading, temperature, pH, residence time, substrate concentration, and agitation. To decrease the amount of fresh water used and thereby waste water produced, the sugar-rich prehydrolysate from the pretreatment step was included in the enzymatic hydrolysis of the solid fraction, resulting in a reduction in the cellulose conversion of up to 36%. Different prehydrolysate detoxification methods, such as treatment with Ca(OH){sub 2}, laccase, and fermentation using yeast, were investigated. The latter was shown to be very efficient. The amount of fresh water used can be further reduced by recycling various process streams. This was simulated experimentally in a bench-scale process. A reduction in fresh water demand of 50% was obtained without any further negative effects on either hydrolysis or fermentation.

  1. Long-wave UVA offers partial protection against UVB-induced

    DEFF Research Database (Denmark)

    Skov, L.; Villadsen, L.; Ersbøll, Bjarne Kjær

    2000-01-01

    Ultraviolet-B (UVB, 280–320 nm) interferes with the generation of cell-mediated immunity to contact allergens applied epicutaneously on the irradiated site. To investigate whether pretreatment with UVA-1 (340–400 nm) protects against the UVB-induced immune suppression we sensitized human volunteers...... with diphenylcyclopropenone (DPCP) on normal buttock skin (n=12), on UVB-irradiated buttock skin (n=21), on buttock skin pretreated with UVA-1 (n=12), and on buttock skin pretreated with UVA-1 and thereafter irradiated with UVB (n=22). Sensitization on UVB-irradiated skin reduced the immunization rate to DPCP compared...

  2. ENZYMATIC HYDROLYSIS OF SWITCHGRASS AND COASTAL BERMUDA GRASS PRETREATED USING DIFFERENT CHEMICAL METHODS

    Directory of Open Access Journals (Sweden)

    Jiele Xu

    2011-06-01

    Full Text Available To investigate the effects of biomass feedstock and pretreatment method on the enzyme requirement during hydrolysis, swichgrass and coastal Bermuda grass pretreated using H2SO4, NaOH, and Ca(OH2 at the optimal conditions were subjected to enzymatic hydrolysis using two enzyme combinations: NS 50013 + NS 50010 and Cellic CTec + Cellic HTec. The enzyme loadings were optimized, and correlations between feedstock property, pretreatment strategy, and enzyme usage were evaluated. The results show that pretreatment methods resulting in greater lignin contents in the pretreated biomass were generally associated with higher enzyme requirements. More sugars could be recovered from alkaline-pretreated biomass during enzymatic hydrolysis due to the better carbohydrate preservation achieved at mild pretreatment temperatures. The cellulase enzyme, Cellic CTec, was more efficient in catalyzing the hydrolysis of coastal Bermuda grass, a feedstock more digestible than the pretreated swichgrass, following pretreatment with NaOH or Ca(OH2.

  3. Permitting plan for project W-236B, initial pretreatment module

    International Nuclear Information System (INIS)

    Tollefson, K.S.

    1995-01-01

    The Tank Waste Remediation System pretreatment process mission is to separate high-level and low-level waste fractions. A comprehensive review of environmental regulations has indicated that several environmental reviews, permits, and approvals are required before construction and operation of the facility. This revised document provides a summary of permit application data requirements, alternative strategies for permit completion and approval, as well as the probability of success for each alternative for the Initial Pretreatment Module resulting from recent revisions to the Tri-Party Agreement

  4. GSDO Program Hexavalent Chrome Alternatives: Final Pretreatments Test Report

    Science.gov (United States)

    Kessel, Kurt

    2013-01-01

    Hexavalent chrome free pretreatments should be considered for use on Ground Support Equipment (OSE) and Electrical Ground Support Equipment (EOSE). Both of the hexavalent chrome free pretreatments (Metalast TCP HF and SurTec 650C) evaluated by this project met, and in some instances exceeded, the requirements ofMIL-DTL-5541 "Chemical Conversion Coatings on Aluminum and Aluminum Alloys". For DC resistance measurements, both Metalast TCP HF and SurTec (!50C met initial requirements following assembly and in many cases continued to maintain passing readings for the duration of testing.

  5. Direct ethanol conversion of pretreated straw by Fusarium oxysporum

    Energy Technology Data Exchange (ETDEWEB)

    Christakopoulos, P.; Koullas, D.P.; Kekos, D.; Koukios, E.G.; Macris, B.J. (National Technical Univ., Athens (GR). Dept. of Chemical Engineering)

    1991-01-01

    Factors affecting the direct conversion of alkali pretreated straw to ethanol by Fusarium oxysporum F3 were investigated and the alkali level used for pretreatment and the degree of delignification of straw were found to be the most important. A linear correlation between ethanol yield and both the degree of straw delignification and the alkali level was observed. At optimum delignified straw concentration (4% w/v), a maximum ethanol yield of 0.275 g ethanol g{sup -1} of straw was obtained corresponding to 67.8% of the theoretical yield. (author).

  6. Pretreatment of sawdust and its hydrolysis with immobilised enzymes

    International Nuclear Information System (INIS)

    Kumakura, M.; Kaetsu, I.

    1988-01-01

    The pretreatment of sawdust by radiation and its hydrolysis with immobilised cellulase were studied. The sawdust was irradiated with a number of different irradiation doses and crushed with two kinds of crusher; pulveriser and ball mill. In ball-mill crushing, the crushing time to get a fine powder was reduced by radiation treatment and the conversion yield of cellulose to glucose in the enzyme hydrolysis was increased. It was found that sawdust pretreated by radiation and subsequent crushing was efficiently hydrolysed by immobilised cellulase which itself was obtained by a radiation polymerisation technique. (author)

  7. TWRS tank waste pretreatment process development hot test siting report

    International Nuclear Information System (INIS)

    Howden, G.F.; Banning, D.L.; Dodd, D.A.; Smith, D.A.; Stevens, P.F.; Hansen, R.I.; Reynolds, B.A.

    1995-02-01

    This report is the sixth in a series that have assessed the hot testing requirements for TWRS pretreatment process development and identified the hot testing support requirements. This report, based on the previous work, identifies specific hot test work packages, matches those packages to specific hot cell facilities, and provides recommendations of specific facilities to be employed for the pretreatment hot test work. Also identified are serious limitations in the tank waste sample retrieval and handling infrastructure. Recommendations are provided for staged development of 500 mL, 3 L, 25 L and 4000 L sample recovery systems and specific actions to provide those capabilities

  8. Development and application of free pretreatment container steel

    Science.gov (United States)

    Yang, Y.; Liu, Y.; Han, B.; Wei, B.; Wang, S. Z.

    2017-12-01

    Due to economic and environmental advantages pre-treatment containers have good big development prospects, which can avoid shot blasting processes, and decrease the noise and dust pollution. By analyzing requirements of the container steel surface quality, target oxide scale structure of free pretreatment container steel has been determined. Trial process was carried out, and test results showed that the oxide scale achieved the desired objects, oxide scale with outer thin Fe3O4 layer and inner eutectoid α-Fe+Fe3O4. Salt spray test, second adhesion test, and modeling performance basically corroborated the container feasibility.

  9. Study on the Pretreating Approaches for the Potato Straws

    OpenAIRE

    An Yumin; Wang Jukui; Huang Ye; Xu Xiaomei

    2016-01-01

    This paper proposes an approach to pretreat the potato straws. Specifically, potato straws are handled using various kinds of chemical solutions, including HCI, H2SO4, NaOH and NaOH+H2O2, under different concentrations. For each kind of solution, particular indicators, such as the cellulose content as well as scarification ratio of the treated straws, are studied in the paper. Based on orthogonal experiments, the best pretreatment effect is obtained by using the solution of 4% NaOH under temp...

  10. Effects of stress and. beta. -funal trexamine pretreatment on morphine analgesia and opioid binding in rats

    Energy Technology Data Exchange (ETDEWEB)

    Adams, J.U.; Andrews, J.S.; Hiller, J.M.; Simon, E.J.; Holtzman, S.G.

    1987-12-28

    This study was essentially an in vivo protection experiment designed to test further the hypothesis that stress induces release of endogenous opiods which then act at opioid receptors. Rats that were either subjected to restraint stress for 1 yr or unstressed were injected ICV with either saline or 2.5 ..mu..g of ..beta..-funaltrexamine (..beta..-FNA), an irreversible opioid antagonist that alkylates the mu-opioid receptor. Twenty-four hours later, subjects were tested unstressed for morphine analgesia or were sacrificed and opioid binding in brain was determined. (/sup 3/H)D-Ala/sup 2/NMePhe/sup 4/-Gly/sup 5/(ol)enkephalin (DAGO) served as a specific ligand for mu-opioid receptors, and (/sup 3/H)-bremazocine as a general ligand for all opioid receptors. Rats injected with saline while stressed were significantly less sensitive to the analgesic action of morphine 24 hr later than were their unstressed counterparts. ..beta..-FNA pretreatment attenuated morphine analgesia in an insurmountable manner. Animals pretreated with ..beta..-FNA while stressed were significantly more sensitive to the analgesic effect of morphine than were animals that received ..beta..-FNA while unstressed. ..beta..-FNA caused small and similar decreases in (/sup 3/H)-DAGO binding in brain of both stressed and unstressed animals. 35 references, 2 figures, 2 tables.

  11. Radiation protection

    International Nuclear Information System (INIS)

    Jain, Aman; Sharma, Shivam; Parasher, Abhishek

    2014-01-01

    Radiation dose measurement, field of radiobiology, is considered to be critical factor for optimizing radiation protection to the health care practitioners, patients and the public. This lead to equipment that has dose - area product meters permanently installed. In many countries and even institution, the range of equipment is vast and with the opportunity for radiation protection and dose recording varies considerably. Practitioners must move with the changed demands of radiation protection but in many cases without assistance of modern advancements in technology Keeping the three basic safety measures Time, Dose and Shielding we can say 'Optimum dose is safe dose' instead of 'No dose is safe dose'. The purpose enclosed within the title 'Radiation Protection'. The use of radiation is expanding widely everyday around the world and crossing boundaries of medical imaging, diagnostic and. The way to get the ''As low as reasonably achievable' is only achievable by using methodology of radiation protection and to bring the concern of general public and practitioners over the hazards of un-necessary radiation dose. Three basic principles of radiation protection are time, distance and shielding. By minimizing the exposure time increasing the distance and including the shielding we can reduce the optimum range of dose. The ability of shielding material to attenuate radiation is generally given as half value layer. This is the thickness of the material which will reduce the amount of radiation by 50%. Lab coat and gloves must be worn when handling radioactive material or when working in a labeled radiation work area. Safety glasses or other appropriate splash shields should be used when handling radioactive material. 1. Reached to low dose level to occupational workers, public as per prescribed dose limit. 2. By mean of ALARA principle we achieved the protection from radiation besides us using the radiation for our benefit

  12. Machine Protection

    International Nuclear Information System (INIS)

    Schmidt, R

    2014-01-01

    The protection of accelerator equipment is as old as accelerator technology and was for many years related to high-power equipment. Examples are the protection of powering equipment from overheating (magnets, power converters, high-current cables), of superconducting magnets from damage after a quench and of klystrons. The protection of equipment from beam accidents is more recent. It is related to the increasing beam power of high-power proton accelerators such as ISIS, SNS, ESS and the PSI cyclotron, to the emission of synchrotron light by electron–positron accelerators and FELs, and to the increase of energy stored in the beam (in particular for hadron colliders such as LHC). Designing a machine protection system requires an excellent understanding of accelerator physics and operation to anticipate possible failures that could lead to damage. Machine protection includes beam and equipment monitoring, a system to safely stop beam operation (e.g. dumping the beam or stopping the beam at low energy) and an interlock system providing the glue between these systems. The most recent accelerator, the LHC, will operate with about 3 × 10 14 protons per beam, corresponding to an energy stored in each beam of 360 MJ. This energy can cause massive damage to accelerator equipment in case of uncontrolled beam loss, and a single accident damaging vital parts of the accelerator could interrupt operation for years. This article provides an overview of the requirements for protection of accelerator equipment and introduces the various protection systems. Examples are mainly from LHC, SNS and ESS

  13. Machine Protection

    CERN Document Server

    Schmidt, R

    2014-01-01

    The protection of accelerator equipment is as old as accelerator technology and was for many years related to high-power equipment. Examples are the protection of powering equipment from overheating (magnets, power converters, high-current cables), of superconducting magnets from damage after a quench and of klystrons. The protection of equipment from beam accidents is more recent. It is related to the increasing beam power of high-power proton accelerators such as ISIS, SNS, ESS and the PSI cyclotron, to the emission of synchrotron light by electron–positron accelerators and FELs, and to the increase of energy stored in the beam (in particular for hadron colliders such as LHC). Designing a machine protection system requires an excellent understanding of accelerator physics and operation to anticipate possible failures that could lead to damage. Machine protection includes beam and equipment monitoring, a system to safely stop beam operation (e.g. dumping the beam or stopping the beam at low energy) and an ...

  14. Factors affecting seawater-based pretreatment of lignocellulosic date palm residues

    DEFF Research Database (Denmark)

    Fang, Chuanji; Thomsen, Mette Hedegaard; Frankaer, Christian Grundahl

    2017-01-01

    Seawater-based pretreatment of lignocellulosic biomass is an innovative process at research stage. With respect to process optimization, factors affecting seawater-based pretreatment of lignocellulosic date palm residues were studied for the first time in this paper. Pretreatment temperature (180...... °C–210 °C), salinity of seawater (0 ppt–50 ppt), and catalysts (H2SO4, Na2CO3, and NaOH) were investigated. The results showed that pretreatment temperature exerted the largest influence on seawater-based pretreatment in terms of the enzymatic digestibility and fermentability of pretreated solids...

  15. Methods of pretreating comminuted cellulosic material with carbonate-containing solutions

    Energy Technology Data Exchange (ETDEWEB)

    Francis, Raymond

    2012-11-06

    Methods of pretreating comminuted cellulosic material with an acidic solution and then a carbonate-containing solution to produce a pretreated cellulosic material are provided. The pretreated material may then be further treated in a pulping process, for example, a soda-anthraquinone pulping process, to produce a cellulose pulp. The pretreatment solutions may be extracted from the pretreated cellulose material and selectively re-used, for example, with acid or alkali addition, for the pretreatment solutions. The resulting cellulose pulp is characterized by having reduced lignin content and increased yield compared to prior art treatment processes.

  16. Techno-economic analysis of organosolv pretreatment process from lignocellulosic biomass

    DEFF Research Database (Denmark)

    Rodrigues Gurgel da Silva, Andrè; Errico, Massimiliano; Rong, Ben-Guang

    2018-01-01

    data, we propose a feasible process flowsheet for organosolv pretreatment. Simulation of the pretreatment process provided mass and energy balances for a techno-economic analysis, and the values were compared with the most prevalent and mature pretreatment method: diluted acid. Organosolv pretreatment...... required more energy, 578.1 versus 213.8 MW for diluted acid pretreatment, but resulted in a higher ethanol concentration after the biomass fermentation, 11.1% compared to 5.4%. Total annual costs (TACs) calculations showed advantages for diluted acid pretreatment, but future improvements explored...

  17. Pretreatment method for radioactive iodine-containing liquid wastes and pretreatment device

    International Nuclear Information System (INIS)

    Wakaida, Yasuo.

    1996-01-01

    Heretofore, radioactive iodine-containing liquid wastes have been discharged directly to a storing and decaying storage vessel to conduct a water draining treatment. In the present invention, the radioactive iodine-containing liquid wastes to be discharged are not discharged to the storage vessel directly but injected to a filling tank, as a pretreatment, to distinguish whether proteins are mixed in the liquid wastes or not. When proteins are mixed, miscellaneous materials such as proteins are recovered and removed by a protein processing system. When proteins are not mixed, radioactive iodine is recovered and removed directly by an iodine processing system. With such procedures, water draining treatment in the storing and decaying storage vessel is mitigated, and even when the amount of the radioactive iodine-containing liquid wastes is increased, the existent maintaining and decaying storage vessel can be used as it is. Accordingly, a safe water draining treatment with good efficiency can be conducted relative to radioactive iodine-containing liquid wastes at a reduced cost. (T.M.)

  18. Machine Protection

    International Nuclear Information System (INIS)

    Zerlauth, Markus; Schmidt, Rüdiger; Wenninger, Jörg

    2012-01-01

    The present architecture of the machine protection system is being recalled and the performance of the associated systems during the 2011 run will be briefly summarized. An analysis of the causes of beam dumps as well as an assessment of the dependability of the machine protection systems (MPS) itself is being presented. Emphasis will be given to events that risked exposing parts of the machine to damage. Further improvements and mitigations of potential holes in the protection systems will be evaluated along with their impact on the 2012 run. The role of rMPP during the various operational phases (commissioning, intensity ramp up, MDs...) will be discussed along with a proposal for the intensity ramp up for the start of beam operation in 2012

  19. Machine Protection

    CERN Document Server

    Zerlauth, Markus; Wenninger, Jörg

    2012-01-01

    The present architecture of the machine protection system is being recalled and the performance of the associated systems during the 2011 run will be briefly summarized. An analysis of the causes of beam dumps as well as an assessment of the dependability of the machine protection systems (MPS) itself is being presented. Emphasis will be given to events that risked exposing parts of the machine to damage. Further improvements and mitigations of potential holes in the protection systems will be evaluated along with their impact on the 2012 run. The role of rMPP during the various operational phases (commissioning, intensity ramp up, MDs...) will be discussed along with a proposal for the intensity ramp up for the start of beam operation in 2012.

  20. Machine Protection

    Energy Technology Data Exchange (ETDEWEB)

    Zerlauth, Markus; Schmidt, Rüdiger; Wenninger, Jörg [European Organization for Nuclear Research, Geneva (Switzerland)

    2012-07-01

    The present architecture of the machine protection system is being recalled and the performance of the associated systems during the 2011 run will be briefly summarized. An analysis of the causes of beam dumps as well as an assessment of the dependability of the machine protection systems (MPS) itself is being presented. Emphasis will be given to events that risked exposing parts of the machine to damage. Further improvements and mitigations of potential holes in the protection systems will be evaluated along with their impact on the 2012 run. The role of rMPP during the various operational phases (commissioning, intensity ramp up, MDs...) will be discussed along with a proposal for the intensity ramp up for the start of beam operation in 2012.

  1. A new magnesium bisulfite pretreatment (MBSP) development for bio-ethanol production from corn stover.

    Science.gov (United States)

    Yu, Heng; Ren, Jiwei; Liu, Lei; Zheng, Zhaojuan; Zhu, Junjun; Yong, Qiang; Ouyang, Jia

    2016-01-01

    This study established a new more neutral magnesium bisulfate pretreatment (MBSP) using magnesium bisulfate as sulfonating agent for improving the enzymatic hydrolysis efficiency of corn stover. Using the MBSP with 5.21% magnesium bisulfate, 170°C and pH 5.2 for 60 min, about 90% of lignin and 80% of hemicellulose were removed from biomass and more than 90% cellulose conversion of substrate was achieved after 48 h hydrolysis. About 6.19 kg raw corn stover could produce 1 kg ethanol by Saccharomyces cerevisiae. Meanwhile, MBSP also could protect sugars from excessive degradation, prevent fermentation inhibition formation and directly convert the hemicelluloses into xylooligosaccharides as higher-value products. These results suggested that the MBSP method offers an alternative approach to the efficient conversion of nonwoody lignocellulosic biomass to ethanol and had broad space for development. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Effects of L-carnitine pretreatment in methamphetamine and 3-nitropropionic acid-induced neurotoxicity.

    Science.gov (United States)

    Binienda, Zbigniew K; Przybyla, Beata D; Robinson, Bonnie L; Salem, Nadia; Virmani, Ashraf; Amato, Antonino; Ali, Syed F

    2006-08-01

    Adult, male Sprague-Dawley rats were injected with 3-ni-tropropionic acid (3-NPA) at 30 mg/kg or methamphetamine (METH) at 20 mg/kg alone or following pretreatment with L-cartnitine (LC) at 100 mg/kg. Rectal temperature was measured before and 4 h following treatment. Animals were sacrificed at 4 h posttreatment. Monoamine neurotransmitters, dopamine (DA) and serotonin (5-HT), and their metabolites were analyzed in the striatum using high-performance liquid chromatography method coupled with electrochemical detection (HPLC/ED). Transcripts of several genes related to DA metabolism were quantified using real time reverse transciption polymerase chain reaction (RT-PCR). Core temperature decreased significantly after 3-NPA acid and increased in METH-treated rats (P protection against METH toxicity.

  3. Furfural production from biomass pretreatment hydrolysate using vapor-releasing reactor system.

    Science.gov (United States)

    Liu, Lu; Chang, Hou-Min; Jameel, Hasan; Park, Sunkyu

    2018-03-01

    Biomass hydrolysate from autohydrolysis pretreatment was used for furfural production considering it is in rich of xylose, xylo-oligomers, and other decomposition products from hemicellulose structure. By using the vapor-releasing reactor system, furfural was protected from degradation by separating it from the reaction media. The maximum furfural yield of 73% was achieved at 200 °C for biomass hydrolysate without the use of the catalyst. This is because the presence of organic acids such as acetic acid in hydrolysate functioned as a catalyst. According to the results in this study, biomass hydrolysate with a vapor-releasing system proves to be efficient for furfural production. The biorefinery process which allows the separation of xylose-rich autohydrolysate from other parts from biomass feedstock also improves the overall application of the biomass. Copyright © 2018 Elsevier Ltd. All rights reserved.

  4. Physical protection

    International Nuclear Information System (INIS)

    Myre, W.C.; DeMontmollin, J.M.

    1989-01-01

    Serious concern about physical protection of nuclear facilities began around 1972. R and D was initiated at Sandia National Laboratories which had developed techniques to protect weapons for many years. Special vehicles, convoy procedures, and a communications system previously developed for weapons shipments were improved and extended for shipments of other sensitive materials. Barriers, perimeter alarms, portal and internal control systems were developed, tested, and published in handbooks and presented at symposia. Training programs were initiated for U.S. and foreign personnel. Containment and surveillance techniques were developed for the IAEA. Presently emphasis is on computer security, active barriers, and techniques to prevent theft or sabotage by ''insiders''

  5. Influence of pre-treatments on the desorption isotherm ...

    African Journals Online (AJOL)

    Influence of pre-treatments on the desorption isotherm characteristics of plaintain. P-N T Johnson. Full Text: EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT · http://dx.doi.org/10.4314/gjs.v39i1.15851 · AJOL African Journals Online. HOW TO USE AJOL... for Researchers · for ...

  6. The Use of Clay-Polymer Nanocomposites in Wastewater Pretreatment

    Science.gov (United States)

    Rytwo, Giora

    2012-01-01

    Some agricultural effluents are unsuitable for discharge into standard sewage-treatment plants: their pretreatment is necessary to avoid clogging of the filtering devices by colloidal matter. The colloidal stability of the effluents is mainly due to mutual repulsive forces that keep charged particles in suspension. Pretreatment processes are based on two separate stages: (a) neutralization of the charges (“coagulation”) and (b) bridging between several small particles to form larger aggregates that sink, leaving clarified effluent (“flocculation”). The consequent destabilization of the colloidal suspension lowers total suspended solids (TSSs), turbidity, and other environmental quality parameters, making the treatments that follow more efficient. Clay-based materials have been widely used for effluent pretreatment and pollutant removal. This study presents the use of nanocomposites, comprised of an anchoring particle and a polymer, as “coagoflocculants” for the efficient and rapid reduction of TSS and turbidity in wastewater with a high organic load. The use of such particles combines the advantages of coagulant and flocculant by neutralizing the charge of the suspended particles while bridging between them and anchoring them to a denser particle (the clay mineral), enhancing their precipitation. Very rapid and efficient pretreatment is achieved in one single treatment step. PMID:22454607

  7. Microalgal biomass pretreatment for bioethanol production: a review

    Directory of Open Access Journals (Sweden)

    Jesús Velazquez-Lucio

    2018-03-01

    Full Text Available Biofuels derived from microalgae biomass have received a great deal of attention owing to their high potentials as sustainable alternatives to fossil fuels. Microalgae have a high capacity of CO2 fixation and depending on their growth conditions, they can accumulate different quantities of lipids, proteins, and carbohydrates. Microalgal biomass can, therefore, represent a rich source of fermentable sugars for third generation bioethanol production. The utilization of microalgal carbohydrates for bioethanol production follows three main stages: i pretreatment, ii saccharification, and iii fermentation. One of the most important stages is the pretreatment, which is carried out to increase the accessibility to intracellular sugars, and thus plays an important role in improving the overall efficiency of the bioethanol production process. Diverse types of pretreatments are currently used including chemical, thermal, mechanical, biological, and their combinations, which can promote cell disruption, facilitate extraction, and result in the modification the structure of carbohydrates as well as the production of fermentable sugars. In this review, the different pretreatments used on microalgae biomass for bioethanol production are presented and discussed. Moreover, the methods used for starch and total carbohydrates quantification in microalgae biomass are also briefly presented and compared.

  8. EVALUATION OF NANOFILTRATION PRETREATMENTS FOR FLUX LOSS CONTROL

    Science.gov (United States)

    Differing nanofiltration pretreatment approaches for Ohio River water were evaluated withthe intent of producing systems with varying degrees of biological fouling. The membrane feed water was alum-coagulated, settled, and filtered Ohio River water (SF-ORW). Five 1.8" x 12" N...

  9. 40 CFR 421.275 - Pretreatment standards for existing sources.

    Science.gov (United States)

    2010-07-01

    ... Nickel 0.000 0.000 (e) Sodium hypochlorite filter backwash. PSES for the Primary Rare Earth Metals...) EFFLUENT GUIDELINES AND STANDARDS NONFERROUS METALS MANUFACTURING POINT SOURCE CATEGORY Primary Rare Earth Metals Subcategory § 421.275 Pretreatment standards for existing sources. Except as provided in 40 CFR...

  10. Effects of Chloramphenicol Pretreatment on Xylazine/ketamine ...

    African Journals Online (AJOL)

    Keyword: Chloramphenicol, xylazine, ketamine, anaesthesia, cats. The effect of pretreatment with a single intramuscular (im) dose of chloramphenicol (10mg/kg) on the anaethesia induced with im injection of ketamine (25mg/kg) was investigated in five cats premedicated with im xylazine (1.0mg/kg) and atropine ...

  11. Effect of seed collection times and pretreatment methods on ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-08-18

    Aug 18, 2008 ... Several basic methods are used to overcome seed- coat dormancy in ... The experiment on seed pretreatment were conducted at Forestry. Research ..... applicability to rural areas where these trees are planted may be limited. .... Forestry. Research News: Indicators and Tools for Restoration & Sustainable.

  12. Sugar cane bagasse pretreatment: An attempt to enhance the ...

    African Journals Online (AJOL)

    +1.5%NaOH. The pretreatment of bagasse with 2.0% H2O2 along with 1.5% NaOH enhanced the biosynthesis of cellulases by H. insolens. Production rate was also optimized with different parameters like thickness of fermentation medium, ...

  13. 40 CFR 35.907 - Municipal pretreatment program.

    Science.gov (United States)

    2010-07-01

    ... industrial survey as required by § 403.8 of this chapter including identification of system users, the... program; (4) A determination of technical information necessary to support development of an industrial waste ordinance or other means of enforcing pretreatment standards; (5) Design of a monitoring...

  14. Comparative effects of pretreatment of stem cuttings of Chromolaena ...

    African Journals Online (AJOL)

    Results showed that there was significant decrease in heavy metal and polyaromatic hydrocarbon (PAH) components of soil. Remediation of Cu and Pb by C. Odorata was best at 0.25% NH2OH.HCl treatment. Remediation efficiencies for PAH and heavy metals were better enhanced with the pretreatment of Chromolaena ...

  15. 40 CFR 418.76 - Pretreatment standard for new sources.

    Science.gov (United States)

    2010-07-01

    ... properties controlled by this section which may be discharged to a publicly owned treatment works by a new source subject to the provisions of this subpart: Pollutant or pollutant property Pretreatment standard BOD5 No limitations. TSS Do. pH Do. Ammonia (as N) 30 mg/l. Nitrate (as N) Do. Total phosphorus (as P...

  16. Separations/pretreatment considerations for Hanford privatization phase 2

    Energy Technology Data Exchange (ETDEWEB)

    Hunt, R.D.; McGinnis, C.P.; Welch, T.D.

    1998-05-01

    The Tank Focus Area is funded to develop, demonstrate, and deploy technologies that will assist in the treatment and closure of its nuclear waste tanks. Pretreatment technologies developed to support the privatization effort by the Department of Energy are reviewed. Advancements in evaporation, solid-liquid separation, sludge treatment, solids controls, sodium management, and radionuclide removal are considered.

  17. Effects of glycyrrhizin pre-treatment on transient ischemic brain ...

    African Journals Online (AJOL)

    Effects of glycyrrhizin pre-treatment on transient ischemic brain injury in mice. ... on transient ischemic brain injury in mice. Chiyeon Lim, Sehyun Lim, Young-Jun Lee, Bokcheul Kong, Byoungho Lee, Chang-Hyun Kim, Buyeo Kim, Suin Cho ... induced brain damage. Keywords: Glycyrrhizin, licorice, stroke, apoptosis ...

  18. Tank Focus Area Pretreatment Program. FY 1995 Program Management Plan

    International Nuclear Information System (INIS)

    Morrison, M.I.; McGinnis, C.P.; Wilkenson, W.T.; Hunt, R.D.

    1995-02-01

    This program management plan (PMP) describes the FY 1995 project plans for the Pretreatment Program of the Tank Focus Area. The Tank Focus Area is one of five areas of environmental concerns originally identified by the Deputy Assistant Secretary for Technology Development (EM-50). Projects in the Tank Focus Area relate to the remediation of liquid waste stored in underground storage tanks at various US Department of Energy sites. The Pretreatment Program is an organizational unit performing work within the Tank Focus Area. The function of the Pretreatment Program is to develop, test, evaluate, and demonstrate new technologies, with emphasis on separations. The 11 Pretreatment Program projects for FY 1995 are (1) Cesium Extraction Testing, (2) Comprehensive Supernate Treatment, (3) Hot Cell Studies, (4) Cesium Removal Demonstration, (5) Out-of-Tank Evaporator Demonstration, (6) Crossflow Filtration, (7) Technical Interchange with CEA, (8) TRUEX Applications, (9) NAC/NAG Process Studies (conducted at Oak Ridge National Laboratory), (10) NAC/NAG Process and Waste Form Studies (conducted at Florida International University), and (11) Program Management. Section 2 of this PMP contains a separate subsection for each FY 1995 project. A brief description of the project, a schedule of major milestones, and a breakdown of costs are provided for each project. The PMP also contains sections that describe the project controls that are in place. Quality assurance, document control, the project management system, and the management organization are described in these sections

  19. Effect of Kaempferol Pretreatment on Myocardial Injury in Rats.

    Science.gov (United States)

    Vishwakarma, Anamika; Singh, Thakur Uttam; Rungsung, Soya; Kumar, Tarun; Kandasamy, Arunvikram; Parida, Subhashree; Lingaraju, Madhu Cholenahalli; Kumar, Ajay; Kumar, Asok; Kumar, Dinesh

    2018-01-20

    The present study was undertaken to evaluate the effect of kaempferol in isoprenaline (ISP)-induced myocardial injury in rats. ISP was administered subcutaneously for two subsequent days to induce myocardial injury. Assessment of myocardial injury was done by estimation of hemodynamic functions, myocardial infarcted area, cardiac injury markers, lipid profile, oxidative stress, pro-inflammatory cytokines and histopathology of heart and liver. Rats pretreated with kaempferol showed reduction in the myocardial infarcted area and heart rate. However, no improvement was observed in change in body weight, mean arterial, systolic and diastolic blood pressure. Kaempferol showed significant decrease in serum LDH, CK-MB, troponin-I and lipid profile. However, highest dose of kaempferol did not reduce the serum triglyceride level. Further, antioxidant enzymes, SOD and catalase, were also higher. However, reduced glutathione, serum SGOT and creatinine did not show any improvement. Kaempferol showed reduction in MDA level. Kaempferol at highest dose showed reduction in pro-MMP-2 expression and MMP-9 level. mRNA expression level of TNF-α was not different in kaempferol-pretreated myocardial injured rats with ISP-alone group. Pretreatment with kaempferol at highest dose showed mild mononuclear infiltration and degenerative changes in heart tissue section of myocardial injured rats. Rats pretreated with kaempferol at higher concentration showed normal cordlike arrangement of hepatocytes with moderate swelling of hepatocytes (vacuolar degeneration) around the central vein. Study suggests that kaempferol attenuated lipid profile, infarcted area and oxidative stress in ISP-induced myocardial injury in rats.

  20. [DNA quantification of blood samples pre-treated with pyramidon].

    Science.gov (United States)

    Zhu, Chuan-Hong; Zheng, Dao-Li; Ni, Rao-Zhi; Wang, Hai-Sheng; Ning, Ping; Fang, Hui; Liu, Yan

    2014-06-01

    To study DNA quantification and STR typing of samples pre-treated with pyramidon. The blood samples of ten unrelated individuals were anticoagulated in EDTA. The blood stains were made on the filter paper. The experimental groups were divided into six groups in accordance with the storage time, 30 min, 1 h, 3 h, 6 h, 12 h and 24h after pre-treated with pyramidon. DNA was extracted by three methods: magnetic bead-based extraction, QIAcube DNA purification method and Chelex-100 method. The quantification of DNA was made by fluorescent quantitative PCR. STR typing was detected by PCR-STR fluorescent technology. In the same DNA extraction method, the sample DNA decreased gradually with times after pre-treatment with pyramidon. In the same storage time, the DNA quantification in different extraction methods had significant differences. Sixteen loci DNA typing were detected in 90.56% of samples. Pyramidon pre-treatment could cause DNA degradation, but effective STR typing can be achieved within 24 h. The magnetic bead-based extraction is the best method for STR profiling and DNA extraction.