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Sample records for prx mntabc trxb

  1. Signaling pathways regulating the expression of Prx1 and Prx2 in the Chick Mandibular Mesenchyme

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    Doufexi, Aikaterini-El; Mina, Mina

    2009-01-01

    Prx1 and Prx2 are members of the aristaless-related homeobox genes shown to play redundant but essential roles in morphogenesis of the mandibular processes. To gain insight into the signaling pathways that regulate expression of Prx genes in the mandibular mesenchyme, we used the chick as a model system. We examined the patterns of gene expression in the face and the roles of signals derived from the epithelium on the expression of Prx genes in the mandibular mesenchyme. Our results demonstrated stage-dependent roles of mandibular epithelium on the expression of Prx in the mandibular mesenchyme and provide evidence for positive roles of members of the fibroblast and hedgehog families derived from mandibular epithelium on the expression of Prx genes in the mandibular mesenchyme. Our studies suggest that endothelin-1 signaling derived from the mesenchyme is involved in restricting the expression of Prx2 to the medial mandibular mesenchyme. PMID:18942149

  2. Laminar shear stress up-regulates peroxiredoxins (PRX) in endothelial cells: PRX 1 as a mechanosensitive antioxidant.

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    Mowbray, Amy L; Kang, Dong-Hoon; Rhee, Sue Goo; Kang, Sang Won; Jo, Hanjoong

    2008-01-18

    Shear stress plays a significant role in endothelial cell biology and atherosclerosis development. Previous work by our group has shown that fluid flow stimulates important functional changes in cells through protein expression regulation. Peroxiredoxins (PRX) are a family of antioxidant enzymes but have yet to be investigated in response to shear stress. Studies have shown that oscillatory shear stress (OS) increases reactive oxygen species (ROS) levels in endothelial cells, whereas laminar shear stress (LS) blocks this response. We hypothesized that PRX are responsible for the anti-oxidative effect of LS. To test this hypothesis, bovine aortic endothelial cells (BAEC) were subjected to LS (15 dyn/cm(2)), OS (+/-5 dyn/cm(2), 1 Hz), or static conditions for 24 h. Using Western blot and immunofluorescence staining, all six isoforms of PRX were identified in BAEC. When compared with OS and static, exposure to chronic LS up-regulated PRX 1 levels intracellularly. LS also increased expression of PRX 5 relative to static controls, but not OS. PRX exhibited broad subcellular localization, with distribution in the cytoplasm, Golgi, mitochondria, and intermediate filaments. In addition, PRX 1 knock down, using specific small interference RNA, attenuated LS-dependent reactive oxygen species reduction in BAEC. However, PRX 5 depletion did not. Together, these results suggest that PRX 1 is a novel mechanosensitive antioxidant, playing an important role in shear-dependent regulation of endothelial biology and atherosclerosis.

  3. Prx1 and Prx2 cooperatively regulate the morphogenesis of the medial region of the mandibular process

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    Balic, Anamaria; Adams, Douglas; Mina, Mina

    2009-01-01

    Mice lacking both Prx1 and Prx2 display severe abnormalities in the mandible. Our analysis showed that complete loss of Prx gene products leads to growth abnormalities in the mandibular processes evident as early as E10.5 associated with changes in the survival of the mesenchyme in the medial region. Changes in the gene expression in the medial and lateral regions were related to gradual loss of a subpopulation of mesenchyme in the medial region expressing eHand. Our analysis also showed that Prx gene products are required for the initiation and maintenance of chondrogenesis and terminal differentiation of the chondrocytes in the caudal and rostral ends of Meckel’s cartilage. The fusion of the mandibular processes in the Prx1/Prx2 double mutants is caused by accelerated ossification. These observations together show that during mandibular morphogenesis Prx gene products play multiple roles including the cell survival, the region-specific terminal differentiation of Meckelian chondrocytes and osteogenesis. PMID:19777594

  4. [Effect of PRX-2 gene transferred by lipofectamine on the proliferation of human skin fibroblasts].

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    Song, Hui-feng; Chai, Jia-ke; Lin, Zi-hao

    2011-10-11

    To explore the effects of PRX-2 gene transferred by lipofectamine on the human skin fibroblasts. Normal human skin fibroblasts were cultured and PRX-2 gene was transferred by lipofectamine. The proliferation of fibroblasts was detected by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) and flow cytometry. The proliferation of PRX-2-transfected fibroblasts was stronger than that of normal counterparts. There were fewer cells during G0-G1 period and more cells during S and G2-M periods. The proliferative index increased. The proliferation of fibroblasts may be modified by transfected PRX-2. Thus PRX-2 plays an important role during the healing of human skin wound.

  5. The Effectiveness of a Pre-Exercise Performance Drink (PRX on Indices of Maximal Cardiorespiratory Fitness

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    Greenwood Lori

    2006-06-01

    Full Text Available Abstract This study examined the effectiveness of a pre-exercise drink (PRX called EM·PACT on indices of maximal cardiorespiratory fitness. Twenty-four males (n = 12 and females (n = 12 ages 18–24 years (20.25 + 1.42, volunteered as subjects. Each subject performed two randomized trials of a VO2max treadmill test within a week of each other. Subjects in this randomized, placebo controlled, counter balanced, crossover design, ingested either a placebo (water or PRX 20 minutes before each exercise bout. VO2max and time to exhaustion (Time during graded exercise testing were evaluated. Using paired samples t-tests, significantly greater mean values were found in VO2max and Time for the PRX trial compared to the placebo trial (p 2max and Time are enhanced by ingestion of PRX prior to exercise testing. The combined results of this investigation may provide meaningful practical applications for coaches and athletes alike regarding ergogenic hydration options.

  6. First Report of a Peroxiredoxin Homologue in Jellyfish: Molecular Cloning, Expression and Functional Characterization of CcPrx4 from Cyanea capillata

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    Ruan, Zengliang; Liu, Guoyan; Wang, Beilei; Zhou, Yonghong; Lu, Jia; Wang, Qianqian; Zhao, Jie; Zhang, Liming

    2014-01-01

    We first identified and characterized a novel peroxiredoxin (Prx), designated as CcPrx4, from the cDNA library of the tentacle of the jellyfish Cyanea capillata. The full-length cDNA sequence of CcPrx4 consisted of 884 nucleotides with an open reading frame encoding a mature protein of 247 amino acids. It showed a significant homology to peroxiredoxin 4 (Prx4) with the highly conserved F-motif (93FTFVCPTEI101), hydrophobic region (217VCPAGW222), 140GGLG143 and 239YF240, indicating that it should be a new member of the Prx4 family. The deduced CcPrx4 protein had a calculated molecular mass of 27.2 kDa and an estimated isoelectric point of 6.3. Quantitative real-time PCR analysis showed that CcPrx4 mRNA could be detected in all the jellyfish tissues analyzed. CcPrx4 protein was cloned into the expression vector, pET-24a, and expressed in Escherichia coli Rosetta (DE3) pLysS. Recombinant CcPrx4 protein was purified by HisTrap High Performance chelating column chromatography and analyzed for its biological function. The results showed that the purified recombinant CcPrx4 protein manifested the ability to reduce hydrogen peroxide and protect supercoiled DNA from oxidative damage, suggesting that CcPrx4 protein may play an important role in protecting jellyfish from oxidative damage. PMID:24413803

  7. Prx II and CKBB proteins interaction under physiological and thermal stress conditions in A549 and HeLa cells

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    A. D. Rakhmetov

    2016-02-01

    Full Text Available Peroxiredoxins (Prxs are versatile enzymes that demonstrate various cell functions as peroxidases, protein chaperones, functions of signal modulators and binding partners. It is well established that Prxs can interact with multiple proteins in cells, such as ASK1, Cdk5-p35, JNK, MIF, PDGF, TKR4 and others. In this study, we attempted to evaluate a possible association between ubiquitous Prx II and ATP/ADP buffering enzyme – brain-type creatine kinase (CKBB. Our co-immunoprecipitation (Co-IP results from the A549 and HeLa cell lysates with overexpressed HA-Prx II and Flag-CKBB have demonstrated strong association between two proteins under non-stressed conditions. This protein interaction was enhanced by the heat treatment with further HA-Prx II precipitation to the immobilized Flag-CKBB depending on the temperature increase. Temperature induced oligomerization of Prx II may contribute to the formation of Prx II conglomera­tes, which in turn, can associate with CKBB and increase signal intensities on the blotted membranes. Thus, such association and oligomerization of Prx II could take part in recovery and protection of the CKBB enzyme activity from inactivation during heat-induced stress.

  8. First‐in‐human assessment of PRX002, an anti–α‐synuclein monoclonal antibody, in healthy volunteers

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    Schenk, Dale B.; Koller, Martin; Ness, Daniel K.; Griffith, Sue G.; Grundman, Michael; Zago, Wagner; Soto, Jay; Atiee, George; Ostrowitzki, Susanne

    2016-01-01

    ABSTRACT Background: α‐Synuclein is a major component of pathologic inclusions that characterize Parkinson's disease. PRX002 is an antibody that targets α‐synuclein, and its murine parent antibody 9E4 has been shown in preclinical studies to reduce α‐synuclein pathology and to protect against cognitive and motor deteriorations and progressive neurodegeneration in human α‐synuclein transgenic mice. Methods: This first‐in‐human, randomized, double‐blind, placebo‐controlled, phase 1 study assessed the impact of PRX002 administered to 40 healthy participants in 5 ascending‐dose cohorts (n = 8/cohort) in which participants were randomly assigned to receive a single intravenous infusion of study drug (0.3, 1, 3, 10, or 30 mg/kg; n = 6/cohort) or placebo (n = 2/cohort). Results: PRX002 demonstrated favorable safety, tolerability, and pharmacokinetic profiles at all doses tested, with no immunogenicity. No serious adverse events, discontinuations as a result of adverse events, or dose‐limiting toxicities were reported. Serum PRX002 exposure was dose proportional; the average terminal half‐life across all doses was 18.2 days. A significant dose‐dependent reduction in free serum α‐synuclein (unbound to PRX002) was apparent within 1 hour after PRX002 administration, whereas total α‐synuclein (free plus bound) increased dose‐dependently, presumably because of the expected change in kinetics following antibody binding. Conclusions: This study demonstrates that serum α‐synuclein can be safely modulated in a dose‐dependent manner after single intravenous infusions of an anti–α‐synuclein antibody. These findings support continued development of PRX002, including further characterization of its safety, tolerability, pharmacokinetics, and pharmacodynamic effects in the central nervous system in patients with Parkinson's disease. © 2016 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of

  9. Preclinical and first-in-human evaluation of PRX-105, a PEGylated, plant-derived, recombinant human acetylcholinesterase-R

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    Atsmon, Jacob [Clinical Research Center, Tel Aviv Sourasky Medical Center, Tel Aviv (Israel); Sackler Faculty of Medicine, Tel Aviv University (Israel); Brill-Almon, Einat; Nadri-Shay, Carmit; Chertkoff, Raul; Alon, Sari [Protalix Biotherapeutics, Science Park, Carmiel (Israel); Shaikevich, Dimitri; Volokhov, Inna; Haim, Kirsten Y. [Clinical Research Center, Tel Aviv Sourasky Medical Center, Tel Aviv (Israel); Sackler Faculty of Medicine, Tel Aviv University (Israel); Bartfeld, Daniel [Protalix Biotherapeutics, Science Park, Carmiel (Israel); Shulman, Avidor, E-mail: avidors@protalix.com [Protalix Biotherapeutics, Science Park, Carmiel (Israel); Ruderfer, Ilya; Ben-Moshe, Tehila; Shilovitzky, Orit [Protalix Biotherapeutics, Science Park, Carmiel (Israel); Soreq, Hermona [Department of Biological Chemistry, Institute of Life Sciences, The Hebrew University of Jerusalem (Israel); Shaaltiel, Yoseph [Protalix Biotherapeutics, Science Park, Carmiel (Israel)

    2015-09-15

    PRX-105 is a plant-derived recombinant version of the human ‘read-through’ acetylcholinesterase splice variant (AChE-R). Its active site structure is similar to that of the synaptic variant, and it displays the same affinity towards organophosphorus (OP) compounds. As such, PRX-105 may serve as a bio-scavenger for OP pesticides and chemical warfare agents. To assess its potential use in prophylaxis and treatment of OP poisoning we conducted several preliminary tests, reported in this paper. Intravenous (IV) PRX-105 was administered to mice either before or after exposure to an OP toxin. All mice who received an IV dose of 50 nmol/kg PRX-105, 2 min before being exposed to 1.33 × LD{sub 50} and 1.5 × LD{sub 50} of toxin and 10 min after exposure to 1.5 × LD{sub 50} survived. The pharmacokinetic and toxicity profiles of PRX-105 were evaluated in mice and mini-pigs. Following single and multiple IV doses (50 to 200 mg/kg) no deaths occurred and no significant laboratory and histopathological changes were observed. The overall elimination half-life (t{sub ½}) in mice was 994 (± 173) min. Additionally, a first-in-human study, to assess the safety, tolerability and pharmacokinetics of the compound, was conducted in healthy volunteers. The t{sub ½} in humans was substantially longer than in mice (average 26.7 h). Despite the small number of animals and human subjects who were assessed, the fact that PRX-105 exerts a protective and therapeutic effect following exposure to lethal doses of OP, its favorable safety profile and its relatively long half-life, renders it a promising candidate for treatment and prophylaxis against OP poisoning and warrants further investigation. - Highlights: • PRX-105 is a PEGylated plant-derived recombinant human acetylcholinesterase-R. • PRX-105 is a promising bio-scavenger for organophosphorous toxins at lethal doses. • PRX-105 was shown to protect animals both prophylactically and post-poisoning. • First-in-human study

  10. The influence of a pre-exercise sports drink (PRX on factors related to maximal aerobic performance

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    Mooneyhan Andy

    2010-03-01

    Full Text Available Abstract Background Pre-exercise sports drinks (PRX are commonly used as ergogenic aids in athletic competitions requiring aerobic power. However, in most cases, claims regarding their effectiveness have not been substantiated. In addition, the ingredients in PRX products must be deemed acceptable by the athletic governing bodies that regulate their use in training and competition. The purpose of this study was to examine the effects of a modified PRX formulation (known as EM·PACT™ from earlier investigations on factors related to maximal aerobic performance during a graded exercise test. The modification consisted of removing creatine to meet the compliance standards set forth by various athletic organizations that regulate the use of nutritional supplements. Methods Twenty-nine male and female college students varying in levels of aerobic fitness participated in a randomized crossover administration of PRX (containing 14 g/serving of fructose, medium-chain triglycerides, and amino acids mixed with 8 oz. of water and placebo (PL 30 minutes prior to performing a treadmill test with approximately one week separation between the trials. VO2max, maximal heart rate (HR, time to exhaustion (Time, and percentage estimated non-protein fat substrate utilization (FA during two a priori submaximal stages of a graded exercise testing were evaluated. Results The VO2max mean value of the PRX trial was significantly greater than the PL trial (P Conclusions The modified PRX formulation utilized in this investigation supports the findings of the previous investigation and its efficacy for enhancing indices of aerobic performance (specifically VO2max, Time, & FA during graded exercise testing.

  11. Convection-enhanced drug delivery of interleukin-4 Pseudomonas exotoxin (PRX321): increased distribution and magnetic resonance monitoring.

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    Mardor, Y; Last, D; Daniels, D; Shneor, R; Maier, S E; Nass, D; Ram, Z

    2009-08-01

    Convection-enhanced drug delivery (CED) enables achieving a drug concentration within brain tissue and brain tumors that is orders of magnitude higher than by systemic administration. Previous phase I/II clinical trials using intratumoral convection of interleukin-4 Pseudomonas exotoxin (PRX321) have demonstrated an acceptable safety and toxicity profile with promising signs of therapeutic activity. The present study was designed to assess the distribution efficiency and toxicity of this PRX321 using magnetic resonance imaging (MRI) and to test whether reformulation with increased viscosity could enhance drug distribution. Convection of low- [0.02% human serum albumin (HSA)] and high-viscosity (3% HSA) infusates mixed with gadolinium-diethylenetriamine pentaacetic acid and PRX321 were compared with low- and high-viscosity infusates without the drug, in normal rat brains. MRI was used for assessment of drug distribution and detection of early and late toxicity. Representative brain samples were subjected to histological examination. Distribution volumes calculated from the magnetic resonance images showed that the average distribution of 0.02% HSA was larger than that of 0.02% HSA with PRX321 by a factor of 1.98 (p convection of the PRX321 infusate used in previous clinical trials can be reversed by increasing infusate viscosity and lead to tripling of the volume of distribution. This effect was not associated with any detectable toxicity. A similar capability to reverse impeded convection was also demonstrated in a CED model using acetic acid. These results will be implemented in an upcoming phase IIb PRX321 CED trial with a high-viscosity infusate.

  12. Preparation and characterization of Bi4–xPrxTi3O12 solid solutions

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    A. I. Klyndyuk

    2017-12-01

    Full Text Available The Bi4–xPrxTi3O12 (BPT solid solutions (x = 0.05, 0.10, 0.15 with small praseodymium content were prepared by solid-state method. Thermal, electric, and dielectric properties of BPT were studied. It was revealed that BPT titanates crystalize in аn orthorhombic structure and exhibit p-type semiconductivity. Dielectric constant of BPT increased, Curie temperature (TC, electrical conductivity and dielectric losses decreased, but lattice parameters and thermo-EMF coefficient remained practically unchanged with the increase of praseodymium content in layered Bi4–xPrxTi3O12. It was determined that activation energy of direct current (DC electrical conductivity and linear thermal expansion coefficient (LTEC of BPT changes at ferroelectric (FE → paraelectric (PE phase transition. The activation energy and LTEC changed below and above TC from 1.08–1.56 eV to 0.45–0.86 eV and from (9.10–10.80×10–6 K–1 to (13.12-14.61×10–6 K–1, respectively. The AC electrical conductivity studies of BPT illustrated short-range order with ionic translations assisted by small-polaron hopping.

  13. The effects of PRX-07034, a novel 5-HT6 antagonist, on cognitive flexibility and working memory in rats

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    Mohler, Eric G.; Baker, Phillip M.; Gannon, Kimberly S.; Jones, Simon S.; Shacham, Sharon; Sweeney, John A.

    2012-01-01

    Rationale Accumulating evidence indicates that schizophrenia and autism spectrum disorder patients are marked by cognitive deficits in working memory and strategy switching. There is accumulating evidence that 5-hydroxytryptamine (5-HT)6 receptors may serve as a useful target to improve cognitive functioning. Objectives In the present experiments, the novel 5-HT6 antagonist, PRX-07034, was examined for its selectivity of the 5-HT6 receptor, as well as its effect on delayed spontaneous alternation and strategy switching. Methods The binding affinity of PRX-07034 to the 5-HT6 receptor, other 5-HT receptors, as well as other G-protein coupled receptors, ion channels, and transporters was evaluated. Cyclic AMP production was measured from transfected HEK-293 cells. In separate behavioral experiments, rats received different doses of PRX-07034 (0.1, 1, or 3 mg/kg, i.p.) 30 min prior to delayed spontaneous alternation testing or prior to the acquisition and switch phases in a place–response switch test. Results The results indicated that PRX-07034 is both a potent (Ki = 4–8 nM) and highly selective 5-HT6 receptor antagonist (≥100-fold selectivity for the 5-HT6 receptor compared to 68 other GPCRs, ion channels, and transporters, except D3 (Ki = 71 nM) and 5-HT1B (Ki = 260 nM) receptors. For cyclic AMP quantification, PRX-07034 demonstrated antagonist activity (IC50 = 19 nM) without an effect on basal levels and did not show any agonist activity up to 10 µM. PRX-07034 at 1 and 3 mg/kg (but not 0.1 mg/kg) significantly enhanced delayed spontaneous alternation. The drug at 1 and 3 mg/kg also enhanced switching between a place and response strategy, but did not affect initial learning of either a place or response discrimination. Conclusions These findings demonstrate that PRX-07034 is a selective 5-HT6 receptor antagonist that may represent a novel treatment for enhancing working memory and cognitive flexibility. PMID:21989804

  14. Bedside Xenon-CT Shows Lower CBF in SAH Patients with Impaired CBF Pressure Autoregulation as Defined by Pressure Reactivity Index (PRx).

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    Johnson, Ulf; Engquist, Henrik; Howells, Tim; Nilsson, Pelle; Ronne-Engström, Elisabeth; Lewén, Anders; Rostami, Elham; Enblad, Per

    2016-08-01

    Subarachnoid hemorrhage (SAH) is a disease with a high rate of unfavorable outcome, often related to delayed cerebral ischemia (DCI), i.e., ischemic injury that develops days-weeks after onset, with a multifactorial etiology. Disturbances in cerebral pressure autoregulation, the ability to maintain a steady cerebral blood flow (CBF), despite fluctuations in systemic blood pressure, have been suggested to play a role in the development of DCI. Pressure reactivity index (PRx) is a well-established measure of cerebral pressure autoregulation that has been used to study traumatic brain injury, but not extensively in SAH. To study the relation between PRx and CBF in SAH patients, and to examine if PRx can be used to predict DCI. Retrospective analysis of prospectively collected data. PRx was calculated as the correlation coefficient between mean arterial blood pressure (MABP) and intracranial pressure (ICP) in a 5 min moving window. CBF was measured using bedside Xenon-CT (Xe-CT). DCI was diagnosed clinically. 47 poor-grade mechanically ventilated patients were studied. Patients with disturbed pressure autoregulation (high PRx values) had lower CBF, as measured by bedside Xe-CT; both in the early (day 0-3) and late (day 4-14) acute phase of the disease. PRx did not differ significantly between patients who developed DCI or not. In mechanically ventilated and sedated SAH patients, high PRx (more disturbed CBF pressure autoregulation) is associated with low CBF, both day 0-3 and day 4-14 after onset. The role of PRx as a monitoring tool in SAH patients needs further studying.

  15. The brain-penetrating CXCR4 antagonist, PRX177561, increases the antitumor effects of bevacizumab and sunitinib in preclinical models of human glioblastoma

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    Giovanni Luca Gravina

    2017-01-01

    Full Text Available Abstract Background Glioblastoma recurrence after treatment with the anti-vascular endothelial growth factor (VEGF antibody bevacizumab is characterized by a highly infiltrative and malignant behavior that renders surgical excision and chemotherapy ineffective. It has been demonstrated that anti-VEGF/VEGFR therapies control the invasive phenotype and that relapse occurs through the increased activity of CXCR4. We therefore hypothesized that combining bevacizumab or sunitinib with the novel CXCR4 antagonist, PRX177561, would have superior antitumor activity. Methods The effects of bevacizumab, sunitinib, and PRX177561 were tested alone or in combination in subcutaneous xenografts of U87MG, U251, and T98G cells as well as on intracranial xenografts of luciferase tagged U87MG cells injected in CD1-nu/nu mice. Animals were randomized to receive vehicle, bevacizumab (4 mg/kg iv every 4 days, sunitinib (40 mg/kg po qd, or PRX177561 (50 mg/kg po qd. Results The in vivo experiments demonstrated that bevacizumab and sunitinib increase the in vivo expression of CXCR4, SDF-1α, and TGFβ1. In addition, we demonstrate that the co-administration of the novel brain-penetrating CXCR4 antagonist, PRX177561, with bevacizumab or sunitinib inhibited tumor growth and reduced the inflammation. The combination of PRX177561 with bevacizumab resulted in a synergistic reduction of tumor growth with an increase of disease-free survival (DSF and overall survival (OS, whereas the combination of PRX177561 with sunitinib showed a mild additive effect. Conclusions The CXC4 antagonist PRX177561 may be a valid therapeutic complement to anti-angiogenic therapy, particularly when used in combination with VEGF/VEGFR inhibitors. Therefore, this compound deserves to be considered for future clinical evaluation.

  16. Essential role of cytoplasmic cdk5 and Prx2 in multiple ischemic injury models, in vivo.

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    Rashidian, Juliet; Rousseaux, Maxime W; Venderova, Katerina; Qu, Dianbo; Callaghan, Steve M; Phillips, Maryam; Bland, Ross J; During, Matthew J; Mao, Zixu; Slack, Ruth S; Park, David S

    2009-10-07

    Recent evidence suggests that abnormal activation of cyclin-dependent kinase 5 (cdk5) is a critical prodeath signal in stroke. However, the mechanism(s) by which cdk5 promotes death is unclear. Complicating the role of cdk5 are the observations that cdk5 can exist in multiple cellular regions and possess both prosurvival and prodeath characteristics. In particular, the critical role of cytoplasmic or nuclear cdk5 in neuronal jury, in vivo, is unclear. Therefore, we determined where cdk5 was activated in models of ischemia and how manipulation of cdk5 in differing compartments may affect neuronal death. Here, we show a critical function for cytoplasmic cdk5 in both focal and global models of stroke, in vivo. Cdk5 is activated in the cytoplasm and expression of DNcdk5 localized to the cytoplasm is protective. Importantly, we also demonstrate the antioxidant enzyme Prx2 (peroxiredoxin 2) as a critical cytoplasmic target of cdk5. In contrast, the role of cdk5 in the nucleus is context-dependent. Following focal ischemia, nuclear cdk5 is activated and functionally relevant while there is no evidence for such activation following global ischemia. Importantly, myocyte enhancer factor 2D (MEF2D), a previously described nuclear target of cdk5 in vitro, is also phosphorylated by cdk5 following focal ischemia. In addition, MEF2D expression in this paradigm ameliorates death. Together, our results address the critical issue of cdk5 activity compartmentalization, as well as define critical substrates for both cytoplasmic and nuclear cdk5 activity in adult models of stroke.

  17. Metabolic Interaction between Anthocyanin and Lignin Biosynthesis Is Associated with Peroxidase FaPRX27 in Strawberry Fruit1[W

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    Ring, Ludwig; Yeh, Su-Ying; Hücherig, Stephanie; Hoffmann, Thomas; Blanco-Portales, Rosario; Fouche, Mathieu; Villatoro, Carmen; Denoyes, Béatrice; Monfort, Amparo; Caballero, José Luis; Muñoz-Blanco, Juan; Gershenson, Jonathan; Schwab, Wilfried

    2013-01-01

    Plant phenolics have drawn increasing attention due to their potential nutritional benefits. Although the basic reactions of the phenolics biosynthetic pathways in plants have been intensively analyzed, the regulation of their accumulation and flux through the pathway is not that well established. The aim of this study was to use a strawberry (Fragaria × ananassa) microarray to investigate gene expression patterns associated with the accumulation of phenylpropanoids, flavonoids, and anthocyanins in strawberry fruit. An examination of the transcriptome, coupled with metabolite profiling data from different commercial varieties, was undertaken to identify genes whose expression correlated with altered phenolics composition. Seventeen comparative microarray analyses revealed 15 genes that were differentially (more than 200-fold) expressed in phenolics-rich versus phenolics-poor varieties. The results were validated by heterologous expression of the peroxidase FaPRX27 gene, which showed the highest altered expression level (more than 900-fold). The encoded protein was functionally characterized and is assumed to be involved in lignin formation during strawberry fruit ripening. Quantitative trait locus analysis indicated that the genomic region of FaPRX27 is associated with the fruit color trait. Down-regulation of the CHALCONE SYNTHASE gene and concomitant induction of FaPRX27 expression diverted the flux from anthocyanins to lignin. The results highlight the competition of the different phenolics pathways for their common precursors. The list of the 15 candidates provides new genes that are likely to impact polyphenol accumulation in strawberry fruit and could be used to develop molecular markers to select phenolics-rich germplasm. PMID:23835409

  18. Proteomic profiling of fetal esophageal epithelium, esophageal cancer, and tumor-adjacent esophageal epithelium and immunohistochemical characterization of a representative differential protein, PRX6

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    Guo, Jun-Hui; Xing, Guo-Lan; Fang, Xin-Hui; Wu, Hui-Fang; Zhang, Bo; Yu, Jin-Zhong; Fan, Zong-Min; Wang, Li-Dong

    2017-01-01

    AIM To understand the molecular mechanism of esophageal cancer development and provide molecular markers for screening high-risk populations and early diagnosis. METHODS Two-dimensional electrophoresis combined with mass spectrometry were adopted to screen differentially expressed proteins in nine cases of fetal esophageal epithelium, eight cases of esophageal cancer, and eight cases of tumor-adjacent normal esophageal epithelium collected from fetuses of different gestational age, or esophageal cancer patients from a high-risk area of esophageal cancer in China. Immunohistochemistry (avidin-biotin-horseradish peroxidase complex method) was used to detect the expression of peroxiredoxin (PRX)6 in 91 cases of esophageal cancer, tumor-adjacent normal esophageal tissue, basal cell hyperplasia, dysplasia, and carcinoma in situ, as well as 65 cases of esophageal epithelium from fetuses at a gestational age of 3-9 mo. RESULTS After peptide mass fingerprint analysis and search of protein databases, 21 differential proteins were identified; some of which represent a protein isoform. Varying degrees of expression of PRX6 protein, which was localized mainly in the cytoplasm, were detected in adult and fetal normal esophageal tissues, precancerous lesions, and esophageal cancer. With the progression of esophageal lesions, PRX6 protein expression showed a declining trend (P < 0.05). In fetal epithelium from fetuses at gestational age 3-6 mo, PRX6 protein expression showed a declining trend with age (P < 0.05). PRX6 protein expression was significantly higher in well-differentiated esophageal cancer tissues than in poorly differentiated esophageal cancer tissues (P < 0.05). CONCLUSION Development and progression of esophageal cancer result from interactions of genetic changes (accumulation or superposition). PRX6 protein is associated with fetal esophageal development and cancer differentiation. PMID:28293090

  19. Novel mutations in the PRX and the MTMR2 genes are responsible for unusual Charcot-Marie-Tooth disease phenotypes.

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    Nouioua, Sonia; Hamadouche, Tarik; Funalot, Benoit; Bernard, Rafaëlle; Bellatache, Nora; Bouderba, Radia; Grid, Djamel; Assami, Salima; Benhassine, Traki; Levy, Nicolas; Vallat, Jean-Michel; Tazir, Meriem

    2011-08-01

    Autosomal recessive Charcot-Marie-Tooth diseases, relatively common in Algeria due to high prevalence of consanguineous marriages, are clinically and genetically heterogeneous. We report on two consanguineous families with demyelinating autosomal recessive Charcot-Marie-Tooth disease (CMT4) associated with novel homozygous mutations in the MTMR2 gene, c.331dupA (p.Arg111LysfsX24) and PRX gene, c.1090C>T (p.Arg364X) respectively, and peculiar clinical phenotypes. The three patients with MTMR2 mutations (CMT4B1 family) had a typical phenotype of severe early onset motor and sensory neuropathy with typical focally folded myelin on nerve biopsy. Associated clinical features included vocal cord paresis, prominent chest deformities and claw hands. Contrasting with the classical presentation of CMT4F (early-onset Dejerine-Sottas phenotype), the four patients with PRX mutations (CMT4F family) had essentially a late age of onset and a protracted and relatively benign evolution, although they presented marked spine deformities. These observations broaden the spectrum of clinical phenotypes associated with these two CMT4 forms. Copyright © 2011 Elsevier B.V. All rights reserved.

  20. The Composition and Metabolic Phenotype of Neisseria gonorrhoeae Biofilms

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    Michael A Apicella

    2011-04-01

    Full Text Available N. gonorrhoeae has been shown to form biofilms during cervical infection. Thus, biofilm formation may play an important role in the infection of women. The ability of N. gonorrhoeae to form membrane blebs is crucial to biofilm formation. Blebs contain DNA and outer membrane structures, which have been shown to be major constituents of the biofilm matrix. The organism expresses a DNA thermonuclease that is involved in remodeling of the biofilm matrix. Comparison of the transcriptional profiles of gonococcal biofilms and planktonic runoff indicate that genes involved in anaerobic metabolism and oxidative stress tolerance are more highly expressed in biofilm. The expression of aniA, ccp, and norB, which encode nitrite reductase, cytochrome c peroxidase, and nitric oxide reductase respectively, is required for mature biofilm formation over glass and human cervical cells. In addition, anaerobic respiration occurs in the substratum of gonococcal biofilms and disruption of the norB gene required for anaerobic respiration, results in a severe biofilm attenuation phenotype. It has been demonstrated that accumulation of nitric oxide (NO contributes to the phenotype of a norB mutant and can retard biofilm formation. However, NO can also enhance biofilm formation, and this is largely dependent on the concentration and donation rate or steady state kinetics of NO. The majority of the genes involved in gonococcal oxidative stress tolerance are also required for normal biofilm formation, as mutations in the following genes result in attenuated biofilm formation over cervical cells and/or glass: oxyR, gor, prx, mntABC, trxB, and estD. Overall, biofilm formation appears to be an adaptation for coping with the environmental stresses present in the female genitourinary tract. Therefore, this review will discuss the studies, which describe the composition and metabolic phenotype of gonococcal biofilms.

  1. Critical Thresholds of ICP Derived Continuous Cerebrovascular Reactivity Indices for outcome prediction in Non-Craniectomized TBI Patients: PRx, PAx and RAC.

    Science.gov (United States)

    Zeiler, Frederick Adam; Donnelly, Joseph; Smieleweski, Peter; Menon, David; Hutchinson, Peter John; Czosnyka, Marek

    2017-12-14

    To compare ICP derived cerebrovascular reactivity indices in their ability to predict 6-month outcome, and to determine/compare critical thresholds related to outcome for each index, in adult non-craniectomized traumatic brain injury (TBI). Using a retrospective cohort of non-decompressive craniectomy (non-DC) TBI patients, we performed univariate and multivariate binary logistic regression outcome analysis of: pressure reactivity index (PRx), pulse amplitude index (PAx) and a newly described index calculated as the Regression coefficient between intracranial pressure (ICP) waveform Amplitude and Cerebral perfusion pressure RAC (CPP). Finally, we performed sequential chi-square threshold analysis for each index as they related to 6-month binary outcomes. Outcome was assessed via dichotomized Glasgow Outcome Scores (GOS): A. Favourable (GOS 4 or 5) vs. Unfavourable (GOS 3 or less), B. Alive vs. Dead. 358 non-DC TBI patients were included in all aspects of the analysis. In an analysis of the entire recording period for all patients using univariate binary logistic regression, the AUCs for favourable vs. unfavourable outcome were: PRx (0.573, p<0.0001), PAx (0.606, p<0.0001), and RAC (0.655, p<0.0001). Similarly, the AUCs for Alive vs. Dead outcome were: PRx (0.651, p<0.0001), PAx (0.705, p<0.0001), and RAC (0.722, p<0.0001). RAC displayed superior AUC statistics compared to PRx and PAx, using both univariate and multivariate regression. RAC displayed more stable critical thresholds related to 6-month outcomes. Thresholds for both Favourable vs. Unfavourable and Alive vs. Dead outcomes for PRx, PAx and RAC across the entire recording period were: +0.35 and +0.35, 0 and +0.25, -0.10 and -0.05; respectively. In non-DC TBI patients, RAC appears to be superior to PRx and PAx in 6-month outcome prediction, using both univariate and multivariate logistic regression. Further, RAC displayed more stable critical thresholds associated with binary outcomes at 6 months. Further

  2. Structural, electronic and flux dynamics of Gd(Ba2-xPrxCu3O7+& delta superconductor

    Directory of Open Access Journals (Sweden)

    M. R. Mohammadizadeh and M Akhavan

    2004-06-01

    Full Text Available   The Gd(Ba2-xPrxCu3O single phase polycrystalline samples with 0.00 ≤ x ≤ 1.00 were investigated for structural, electronic and flux dynamic properties. An unusual hump on the resistivity vs. temperature curve of the samples has been observed for particular values of Pr doping. We have found that the Ba atom substitution at the rare earth site could lead to superconductivity in some parts of the grains at Tm~80-90K, which appears as a hump on the (T curve. For all the samples, the two-dimensional variable range hopping (VRH is a dominant conduction mechanism in the normal state. The Pr doping strongly localizes the carriers in the normal state, and finally causes the suppression of superconductivity. The effect of Pr substitution in 123 structure of HTSC at R or Ba site is to increase the pseudo gap temperature Ts, although, Pr at Ba site has a stronger effect on the increase of Ts and suppression of superconductivity. We have also extracted the two dimensionality aspects of HTSC through the similarities between superconductors, two-dimensional electron gas (2D-EG i.e., MOSFETs, and the ultra thin films of conventional superconductors. The magneto resistance of the samples have been studied within thermally activated flux creep and the Ambegaokar and Halperin phase slip models. The derived critical current density, Hc2(T, Hc2(0, and superconducting coherence length show that the Pr- doping, like weak links, decreases the vortex flux pinning energy. Our results imply that understanding the real suppression mechanism of superconductivity by Pr doping in HTSC is connected unavoidably to determination of the exact position of Pr in the structure.

  3. Defect Chemistry and Thermomechanical Properties of Ce0.8PrxTb0.2-xO2-delta

    DEFF Research Database (Denmark)

    Chatzichristodoulou, Christodoulos; Hendriksen, Peter Vang; Hagen, Anke

    2010-01-01

    The oxygen nonstoichiometry (delta) of Ce0.8PrxTb0.2-xO2-delta (x=0, 0.05, 0.10, 0.15, 0.20) was measured as a function of P-O2 at temperatures between 600 and 900 degrees C by coulometric titration and thermogravimetry. A nonideal solution model, allowing for a linear delta dependence...... of the co-dopant. The redox properties strongly depended on the lattice strain energy and the mean metal-oxygen bond strength. The thermal and chemical expansion coefficients were determined by dilatometry. The strongly nonlinear behavior of the thermal expansion coefficient originated from the chemical...... strain due to increasing oxygen nonstoichiometry with increasing temperature....

  4. Identification of B6T173 (ZmPrx35 as the prevailing peroxidase in highly insect-resistant maize (Zea mays, p84C3 kernels by activity-directed purification

    Directory of Open Access Journals (Sweden)

    Laura Margarita eLópez-Castillo

    2015-08-01

    Full Text Available Plant peroxidases (PODs are involved in diverse physiological processes, including defence against pathogens and insects. Contrary to their biological importance, only very few plant peroxidases have been proven on protein level, because their low abundance makes them difficult to detect in standard proteomics work-flows. A statistically significant positive correlation between peroxidase activity and post-harvest insect resistance has been found for maize (Zea mays, p84C3 kernels. In combining activity-directed protein purification, genomic and proteomic tools we found that protein B6T173 (ZmPrx35 is responsible for the majority of the peroxidase activity of the kernel. We successfully produced recombinant ZmPrx35 protein in Escherichia coli and demonstrate both, in vitro activity and the presence of a haem (heme cofactor of the enzyme. Our findings support the screening for insect resistant maize variants and the construction of genetically optimised maize plants.

  5. The normal state transport properties of Nd1-xPrxBa2Cu3O7-δ superconductors and theoretical models

    Directory of Open Access Journals (Sweden)

    R Yazdizadeh

    2012-12-01

    Full Text Available  Polycrystalline samples of Nd1-xPrxBa2Cu3O7-δ with 0≤x≤0.30 were made by standard solid state methods. The transport and superconducting properties were studied by the resistivity and the thermoelectric power measurements as a function of temperature and doping concentration. The resistance and the thermoelectric power were increased by increasing doping concentration. The pseudogap temperature was measured from downturn deviation in a linear dependence of resistance as a function of temperature. The resitivity, the thermoelectric power, the critical temperature, and the pseudogap temperature results suggested that the hole concentration in CuO2 planes was decreased by increasing Pr doping concentration. The resistivity and the thermoelectric power results were analyzed by the bipolaron and the phenomenological narrow band model, respectively. A good agreement between models and data was obtained. On the basis of these models, it was inferred that the localization tendency is one of the main reasons for decreasing the hole concentration in the CuO2 plane, which results in the strong depression of the superconductivity.

  6. The grapevine VviPrx31 peroxidase as a candidate gene involved in anthocyanin degradation in ripening berries under high temperature.

    Science.gov (United States)

    Movahed, Nooshin; Pastore, Chiara; Cellini, Antonio; Allegro, Gianluca; Valentini, Gabriele; Zenoni, Sara; Cavallini, Erika; D'Incà, Erica; Tornielli, Giovanni Battista; Filippetti, Ilaria

    2016-05-01

    Anthocyanin levels decline in some red grape berry varieties ripened under high-temperature conditions, but the underlying mechanism is not yet clear. Here we studied the effects of two different temperature regimes, representing actual Sangiovese (Vitis vinifera L.) viticulture regions, on the accumulation of mRNAs and enzymes controlling berry skin anthocyanins. Potted uniform plants of Sangiovese were kept from veraison to harvest, in two plastic greenhouses with different temperature conditions. The low temperature (LT) conditions featured average and maximum daily air temperatures of 20 and 29 °C, respectively, whereas the corresponding high temperature (HT) conditions were 22 and 36 °C, respectively. The anthocyanin concentration at harvest was much lower in HT berries than LT berries although their profile was similar under both conditions. Under HT conditions, the biosynthesis of anthocyanins was suppressed at both the transcriptional and enzymatic levels, but peroxidase activity was higher. This suggests that the low anthocyanin content of HT berries reflects the combined impact of reduced biosynthesis and increased degradation, particularly the direct role of peroxidases in anthocyanin catabolism. Overexpression of VviPrx31 decreased anthocyanin contents in Petunia hybrida petals under heat stress condition. These data suggest that high temperature can stimulate peroxidase activity thus anthocyanin degradation in ripening grape berries.

  7. The electrical and magnetic properties of ferromagnetic-superconducting compound Ru(Gd1.5-xPrxCe0.5Sr2Cu2O10-δ

    Directory of Open Access Journals (Sweden)

    A Khajehnezhad

    2009-08-01

    Full Text Available   Coexistence of superconductivity and magnetic ordering or their mutually exclusive existence in solids is one of the fundamental problems of solid state physics. To determine the effect of Pr substitution for Gd on electrical and magnetic properties of RuGd1.5Ce0.5Sr2Cu2O10-δ (Ru-1222, Ru(Gd1.5-xPrxCe0.5Sr2Cu2O10-δ with x=0.0, 0.01, 0.03, 0.03 3 , 0.04, 0.05, 0.06, 0.1 have been prepared by the standard solid-state reaction technique. The XRD patterns for various x have been obtained to show their phase purity. The resistivity and magnetoresistivity of samples have been measured at various temperatures and different magnetic fields up to 1.5T . Superconductivity and magnetic parameters such as superconducting transition temperature Tc and magnetic transition Tirr, have been obtained through resistivity curves. The sharp decrease in Tc with x in Ru(Gd1.5-xPrxCe0.5Sr2Cu2O10-δ shows competition between pair breaking by magnetic impurity, hole doping because of different valance of ions, difference in ionic radii and oxygen stoichiometry, which affect on superconducting transition. In Pr substitution for Gd, the small difference between Gd3+ and Pr3+,4+ ionic radii decreases the mean Ru-Ru distance, and as a result, the magnetic exchange interaction can become stronger with increasing x. Both Tc and Tirr decrease with external magnetic field .

  8. Ionic/Electronic Conductivity, Thermal/Chemical Expansion and Oxygen Permeation in Pr and Gd Co-Doped Ceria PrxGd0.1Ce0.9-xO1.95-δ

    DEFF Research Database (Denmark)

    Cheng, Shiyang; Chatzichristodoulou, Christodoulos; Søgaard, Martin

    2017-01-01

    The oxygen permeation flux of Ce0.9Gd0.1O1.95-δ (CGO)-based oxygen transport membranes under oxidizing conditions is limited by the electronic conductivity of the material. This work aims to enhance the bulk ambipolar conductivity of CGO by partial substitution of Ce with the redox active element...... Pr. A series of compositions of PrxGd0.1Ce0.9-xO1.95-δ (x = 0, 0.02, 0.05, 0.08, 0.15, 0.25, 0.3 and 0.4) was prepared by solid state reaction. X-ray powder diffraction (XPD) indicates that Pr is completely dissolved in the fluorite structure up to 40 at.%. Pronounced nonlinear thermal expansion...... behavior was observed as a function of temperature, due to the simultaneous contributions of both thermal and chemical expansion. The electronic and ionic conductivities were measured as a function of temperature and oxygen partial pressure. Within the range from 10 to 15 at.% Pr, a drastic drop...

  9. The effect of PVP on morphology, optical properties and electron paramagnetic resonance of Zn0.5Co0.5Fe2-xPrxO4 nanoparticles

    Science.gov (United States)

    Bitar, Z.; El-Said Bakeer, D.; Awad, R.

    2017-07-01

    Zinc Cobalt nano ferrite doped with Praseodymium, Zn0.5Co0.5Fe2-xPrxO4 (0 ≤ x ≤ 0.2), were prepared by co-precipitation method from an aqueous solution containing metal chlorides and two concentrations of poly(vinylpyrrolidone) (PVP) 0 and 30g/L as capping agent. The samples were characterized using X-ray powder diffraction (XRD), Transmission Electron Microscope (TEM), UV-visible optical spectroscopy, Fourier transform infrared (FTIR) and Electron Paramagnetic Resonance (EPR). XRD results display the formation of cubic spinel structure with space group Fd3m and the lattice parameter (a) is slightly decreased for PVP capping samples. The particle size that determined by TEM, decreases for PVP capping samples. The optical band energy Eg increases for PVP capping samples, confirming the variation of energy gap with the particle size. The FTIR results indicate that the metal oxide bands were shifted for the PVP capping samples. EPR data shows that the PVP addition increases the magnetic resonance field and hence decreases the g-factor.

  10. Expression of recombinant multi-coloured fluorescent antibodies in gor -/trxB- E. coli cytoplasm

    Directory of Open Access Journals (Sweden)

    Markiv Anatoliy

    2011-11-01

    Full Text Available Abstract Background Antibody-fluorophore conjugates are invaluable reagents used in contemporary molecular cell biology for imaging, cell sorting and tracking intracellular events. However they suffer in some cases from batch to batch variation, partial loss of binding and susceptibility to photo-bleaching. In theory, these issues can all be addressed by using recombinant antibody fused directly to genetically encoded fluorescent reporters. However, single-chain fragment variable domains linked by long flexible linkers are themselves prone to disassociation and aggregation, and in some cases with isoelectric points incompatible with use in physiologically relevant milieu. Here we describe a general approach that permits fully functional intracellular production of a range of coloured fluorescent recombinant antibodies with optimally orientated VH/VL interfaces and isoelectric points compatible for use in physiological solutions at pH 7.4 with a binding site to fluorophore stoichiometry of 1:1. Results Here we report the design, assembly, intracellular bacterial production and purification of a panel of novel antibody fluorescent protein fusion constructs. The insertion of monomeric fluorescent protein derived from either Discosoma or Aequorea in-between the variable regions of anti-p185HER2-ECD antibody 4D5-8 resulted in optimal VH/VL interface interactions to create soluble coloured antibodies each with a single binding site, with isoelectric points of 6.5- 6. The fluorescent antibodies used in cell staining studies with SK-BR-3 cells retained the fluorophore properties and antibody specificity functions, whereas the conventional 4D5-8 single chain antibody with a (Gly4Ser3 linker precipitated at physiological pH 7.4. Conclusions This modular monomeric recombinant fluorescent antibody platform may be used to create a range of recombinant coloured antibody molecules for quantitative in situ, in vivo and ex vivo imaging, cell sorting and cell trafficking studies. Assembling the single chain antibody with monomeric fluorescent protein linker facilitates optimal variable domain pairing and alters the isoelectric point of the recombinant 4D5-8 protein conferring solubility at physiological pH 7.4. The efficient intracellular expression of these functional molecules opens up the possibility of developing an alternative approach for tagging intracellular targets with fluorescent proteins for a range of molecular cell biology imaging studies.

  11. Hypoxia and Prx1 in Malignant Progression of Prostate Cancer

    Science.gov (United States)

    2006-09-01

    323–339. 46. Shenton, D.; Grant, C.M. Protein S-thiolation targets glycolysis and protein synthesis in response to oxidative stress in the yeast...P14742 Glucosamine fructose 6 phosphate aminotransferase 183-CKSC 1102 Q15181 Inorganic pyrophosphatase EC 3 6 1 1 Pyrophosph 5101 P20228 Glutamate...P14742 Glucosamine fructose 6 phosphate aminotransferase 183-CKSC 105 P39975 Hypothetical 26 8 kDa protein in DLD3 5 region 4-CPC J .-S . L ee et a l. 5

  12. Hypoxia and Prx1 in Malignant Progression of Prostate Cancer

    Science.gov (United States)

    2007-09-01

    a currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1. REPORT DATE (DD-MM-YYYY) 30-SEP-2007 2. REPORT TYPE...regulator in returning Nrf2, and thereby the expression of Nrf2 target genes, to steady- state level after its activation (44). Such an event would have...Molecular Graphics System. DeLano Scientific LLC, San Carlos, CA 35. Ghosh, D., Sawicki, M., Lala , P., Erman, M., Pangborn, W., Eyzaguirre, J

  13. Modulated antiferromagnetic structure of Nd1-xPrx single crystals

    DEFF Research Database (Denmark)

    McEwen, K. A.; Lebech, Bente; Fort, D.

    1986-01-01

    Neutron diffraction studies of Nd0.75Pr0.25 and Nd0.65Pr0.35 are reported for T≥3K. The magnetic structure of these DHCP alloys is simpler than that of pure Nd: only satellites with qh≈0.13 τ100 were found. The structure has moments on both the hexagonal and cubic sites......Neutron diffraction studies of Nd0.75Pr0.25 and Nd0.65Pr0.35 are reported for T≥3K. The magnetic structure of these DHCP alloys is simpler than that of pure Nd: only satellites with qh≈0.13 τ100 were found. The structure has moments on both the hexagonal and cubic sites...

  14. Evaluation of the Protective Role of XvPrx2 Gene from Xerophyta ...

    African Journals Online (AJOL)

    Miccah

    Chlorophyll contents decreased faster in conventional plants than in transgenics with ... protecting plant cell membranes and DNA from damage. Peroxiredoxins are ..... AGG GCA ATG TAG GC-3'). The PCR ..... relatively stable. These results ...

  15. On the efficient luminescence of beta-Na(La1-xPrx)F-4

    NARCIS (Netherlands)

    Herden, Benjamin; Meijerink, A; Rabouw, Freddy T.; Haase, Markus; Juestel, Thomas

    This work describes the synthesis and the optical properties of beta-NaLaF4 and beta-NaLaF4 doped by Pr3+ as a function of the Pr3+ concentration. It is demonstrated that the emission spectrum is a strong function of the Pr3+ concentration and that the external PL efficiency increases with

  16. Formulation strategy and evaluation of nanocrystal piroxicam orally disintegrating tablets manufacturing by freeze-drying.

    Science.gov (United States)

    Lai, Francesco; Pini, Elena; Corrias, Francesco; Perricci, Jacopo; Manconi, Maria; Fadda, Anna Maria; Sinico, Chiara

    2014-06-05

    Piroxicam (PRX) is a non-steroidal anti-inflammatory drug characterized by a poor water solubility and consequently by a low oral bioavailability. In this work, different nanocrystal orally disintegrating tablets (ODT) were prepared to enhance piroxicam dissolution rate and saturation solubility. PRX nanocrystals were prepared by means of high pressure homogenization technique using poloxamer 188 as stabilizer. Three different ODTs were prepared with the same nanosuspension using different excipients in order to study their effect on the PRX dissolution properties. PRX nanocrystal size and zeta potential were determined by photon correlation spectroscopy. Additional characterization of PRX nanocrystal ODT was carried out by infrared spectroscopy, X-ray powder diffractometry, differential scanning calorimetry. Dissolution study was performed in distilled water (pH 5.5) and compared with PRX coarse suspension ODT, PRX/poloxamer 188 physical mixture, bulk PRX samples and a PRX commercial ODT. All PRX nanocrystal ODT formulations showed a higher drug dissolution rate than coarse PRX ODT. PRX nanocrystal ODT prepared using gelatin or croscarmellose as excipient showed a higher PRX dissolution rate compared with the commercial formulation and ODT prepared using xanthan gum. Overall results confirmed that improved PRX dissolution rate is due to the increased surface-to-volume ratio due to the nanosized drug particle but also revealed the important role of different excipients used. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. Irreversible hyperoxidation of peroxiredoxin 2 is caused by tert-butyl hydroperoxide in human red blood cells

    Directory of Open Access Journals (Sweden)

    Y.I. Ishida

    2014-01-01

    Full Text Available Peroxiredoxin 2 (Prx2 is the third most abundant protein in red blood cells (RBCs. In this study, we have succeeded in implementing the rapid and simultaneous detection of the hyperoxidized (Prx2-SO2/3 and reduced (Prx2-SH forms of Prx2 in human RBCs using reverse phase high-performance liquid chromatography. The detection of a peak corresponding to Prx2-SO2/3 was clearly observed following treatment of tert-butyl hydroperoxide (t-BHP, but not H2O2, and was found to be dose-dependent. The identity of the peak was confirmed as Prx2 by immunoblotting and mass spectrometry analysis. Our results suggest that t-BHP hyperoxidizes cysteine residues in Prx2 more readily than H2O2, and that accumulation of hyperoxidized Prx2 might reflect disruption of redox homeostasis in RBCs.

  18. Enhanced targeting of mitochondrial peroxide defense by the combined use of thiosemicarbazones and inhibitors of thioredoxin reductase.

    Science.gov (United States)

    Myers, Charles R

    2016-02-01

    Peroxiredoxin-3 (Prx3) accounts for about 90% of mitochondrial peroxidase activity, and its marked upregulation in many cancers is important for cell survival. Prx3 oxidation can critically alter peroxide signaling and defense and can be a seminal event in promoting cell death. Here it is shown that this mechanism can be exploited pharmacologically by combinations of clinically available drugs that compromise Prx3 function in different ways. Clinically relevant levels of the thiosemicarbazone iron chelators triapine (Tp) and 2,2'-Dipyridyl-N,N-dimethylsemicarbazone (Dp44mT) promote selective oxidation of mitochondrial Prx3, but not cytosolic Prx1, in multiple human lung and ovarian cancer lines. Decreased cell survival closely correlates with Prx3 oxidation. However, Prx3 oxidation is not merely an indicator of cell death as cytotoxic concentrations of cisplatin do not cause Prx3 oxidation. The siRNA-mediated suppression of either Prx3 or thioredoxin-2, which supports Prx3, enhances Tp's cytotoxicity. Tp-mediated Prx3 oxidation is driven by enhanced peroxide generation, but not by nitric oxide. Many tumors overexpress thioredoxin reductase (TrxR) which supports Prx activity. Direct inhibitors of TrxR (e.g. auranofin, cisplatin) markedly enhanced Tp's cytotoxicity, and auranofin enhanced Prx3 oxidation by low dose Tp. Together, these results support an important role for Prx3 oxidation in the cytotoxicity of Tp, and demonstrate that TrxR inhibitors can significantly enhance Tp's cytotoxicity. Thiosemicarbazone-based regimens could prove effective for targeting Prx3 in a variety of cancers. Copyright © 2015 Elsevier Inc. All rights reserved.

  19. Mitochondrial peroxiredoxin 3 regulates sensory cell survival in the cochlea.

    Directory of Open Access Journals (Sweden)

    Fu-Quan Chen

    Full Text Available This study delineates the role of peroxiredoxin 3 (Prx3 in hair cell death induced by several etiologies of acquired hearing loss (noise trauma, aminoglycoside treatment, age. In vivo, Prx3 transiently increased in mouse cochlear hair cells after traumatic noise exposure, kanamycin treatment, or with progressing age before any cell loss occurred; when Prx3 declined, hair cell loss began. Maintenance of high Prx3 levels via treatment with the radical scavenger 2,3-dihydroxybenzoate prevented kanamycin-induced hair cell death. Conversely, reducing Prx3 levels with Prx3 siRNA increased the severity of noise-induced trauma. In mouse organ of Corti explants, reactive oxygen species and levels of Prx3 mRNA and protein increased concomitantly at early times of drug challenge. When Prx3 levels declined after prolonged treatment, hair cells began to die. The radical scavenger p-phenylenediamine maintained Prx3 levels and attenuated gentamicin-induced hair cell death. Our results suggest that Prx3 is up-regulated in response to oxidative stress and that maintenance of Prx3 levels in hair cells is a critical factor in their susceptibility to acquired hearing loss.

  20. Role of Peroxiredoxin III in the Pathogenesis of Pre-eclampsia as Evidenced in Mice

    Directory of Open Access Journals (Sweden)

    Lianqin Li

    2010-01-01

    Full Text Available As a member of peroxiredoxin (Prx family, PrxIII has been demonstrated to play an important role in scavenging intracellular reactive oxygen species (ROS. Since PrxIII knockout mice exhibited oxidative stress in placentas resembling pathophysiologic changes in placentas of human pre-eclampsia, we measured blood pressure through the carotid artery and detected oxidative status by western blotting in pregnant mice. We did not notice hypertension in pregnant PrxIII knockout mice as compared with wild-type littermates, although endothelin-1 was overexpressed in PrxIII-deficient placentas. Our results indicate that PrxIII is not involved in pre-eclamptic development. Instead, PrxIII is an indispensable antioxidant in placentas where oxidative stress exists.

  1. A peroxidase-dependent apoplastic oxidative burst in cultured Arabidopsis cells functions in MAMP-elicited defense.

    Science.gov (United States)

    O'Brien, Jose A; Daudi, Arsalan; Finch, Paul; Butt, Vernon S; Whitelegge, Julian P; Souda, Puneet; Ausubel, Frederick M; Bolwell, G Paul

    2012-04-01

    Perception by plants of so-called microbe-associated molecular patterns (MAMPs) such as bacterial flagellin, referred to as pattern-triggered immunity, triggers a rapid transient accumulation of reactive oxygen species (ROS). We previously identified two cell wall peroxidases, PRX33 and PRX34, involved in apoplastic hydrogen peroxide (H2O2) production in Arabidopsis (Arabidopsis thaliana). Here, we describe the generation of Arabidopsis tissue culture lines in which the expression of PRX33 and PRX34 is knocked down by antisense expression of a heterologous French bean (Phaseolus vulgaris) peroxidase cDNA construct. Using these tissue culture lines and two inhibitors of ROS generation, azide and diphenylene iodonium, we found that perxoxidases generate about half of the H2O2 that accumulated in response to MAMP treatment and that NADPH oxidases and other sources such as mitochondria account for the remainder of the ROS. Knockdown of PRX33/PRX34 resulted in decreased expression of several MAMP-elicited genes, including MYB51, CYP79B2, and CYP81F2. Similarly, proteomic analysis showed that knockdown of PRX33/PRX34 led to the depletion of various MAMP-elicited defense-related proteins, including the two cysteine-rich peptides PDF2.2 and PDF2.3. Knockdown of PRX33/PRX34 also led to changes in the cell wall proteome, including increases in enzymes involved in cell wall remodeling, which may reflect enhanced cell wall expansion as a consequence of reduced H2O2-mediated cell wall cross-linking. Comparative metabolite profiling of a CaCl2 extract of the PRX33/PRX34 knockdown lines showed significant changes in amino acids, aldehydes, and keto acids but not fatty acids and sugars. Overall, these data suggest that PRX33/PRX34-generated ROS production is involved in the orchestration of pattern-triggered immunity in tissue culture cells.

  2. The role of peroxiredoxin I in cisplatin-induced ototoxicity.

    Science.gov (United States)

    Le, Quang; Tabuchi, Keiji; Warabi, Eiji; Hara, Akira

    2017-04-01

    Peroxiredoxin (Prx) is a new family of antioxidative proteins. Prx I is ubiquitously expressed in various tissues and is important in the defense of tissues from increases in reactive oxygen species (ROS). The present study was designed to examine the expression of Prx subtypes in the mouse cochlea and to show the possible involvement of Prx I in protecting the cochlea against cisplatin ototoxicity. Postnatal-day-3-to-5 wildtype mice and Prx I-deficient mice were used. Prx expression in the cochlea was assessed by real-time PCR assay. Prx I protein expression was examined by immunofluorescence staining. Cochlear explants were exposed to 2, 5, and 10-μM cisplatin for 48h, and the cochlear hair cell losses of the wildtype and Prx I-deficient mice were compared. In addition, the histologic features of the cochlear lateral wall were examined after cisplatin incubation. mRNAs of all Prx subtypes were expressed in the mouse cochlea. Prx I was one of the abundant subtypes and was upregulated after 48-h exposure to 5-μM cisplatin. Immunofluorescence staining showed the ubiquitous expression of Prx I in the cochlea. No difference in cochlear hair cell loss induced by cisplatin was found between the wildtype mice and the Prx I-deficient mice. However, spiral ligament fibrocytes of Prx I-deficient mice were significantly sensitive to cisplatin at 20-μM or lower. Prx I is important for protection of at least the spiral ligament fibrocytes of the cochlear lateral wall in cisplatin ototoxicity. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  3. Differences in Proinflammatory Property of Six Subtypes of Peroxiredoxins and Anti-Inflammatory Effect of Ligustilide in Macrophages.

    Directory of Open Access Journals (Sweden)

    Li-Xue Zhao

    Full Text Available Peroxiredoxins (Prxs are proposed to function as damage-associated molecular patterns (DAMPs and contribute to post-ischemic neuroinflammation and brain injury by activating Toll-like receptor (TLR 4 at the acute and subacute phases after ischemic stroke. However, there are few studies concerning the inflammatory profiles of six distinct subtypes of Prxs (Prx1-Prx6. Our previous study demonstrated that the protective effect of ligustilide (LIG against cerebral ischemia was associated with inhibition of neuroinflammatory response and Prx/TLR4 signaling in rats. Herein, the present study explored the inflammatory members of Prxs and the effect of LIG on their inflammatory responses in macrophages.The murine RAW264.7 macrophages were treated with each of exogenous recombinant Prxs at a range of 1 to 50 nM for 24 h. The WST-1 test showed that Prx3 exhibited a significant cytotoxicity, whereas the rest five Prxs did not affect cellular viability. The quantitative measurements with spectrometry or ELISA indicated that three subtypes, Prx1, Prx2 and Prx4, increased production of proinflammatory mediators, including nitric oxide (NO metabolites, tumor necrosis factor-α (TNF-α, and interleukin-6 (IL-6 in a concentration-dependent manner. Immunostaining demonstrated that 20 nM Prx1, Prx2 or Prx4 significantly increased expression of TLR4 and iNOS and nuclear translocation of NF-κB p65. However, Prx5 and Prx6 showed no poinflammatory effect in macrophages. Remarkably, LIG treatment effectively inhibited the inflammatory response induced by Prx1, Prx2 and Prx4.Three members of Prxs, Prx1, Prx2 and Prx4, are inflammatory DAMPs that induce TLR4 activation and inflammatory response in macrophages, which is effectively inhibited by LIG. These results suggest that inflammatory Prxs-activated macrophages may provide a novel cellular model for screening the potential inhibitors of DAMPs-associated inflammatory diseases such as stroke. Moreover, selective

  4. Dual role of the active-center cysteine in human peroxiredoxin 1: Peroxidase activity and heme binding.

    Science.gov (United States)

    Watanabe, Yuta; Ishimori, Koichiro; Uchida, Takeshi

    2017-02-12

    HBP23, a 23-kDa heme-binding protein identified in rats, is a member of the peroxiredoxin (Prx) family, the primary peroxidases involved in hydrogen peroxide catabolism. Although HBP23 has a characteristic Cys-Pro heme-binding motif, the significance of heme binding to Prx family proteins remains to be elucidated. Here, we examined the effect of heme binding to human peroxiredoxin-1 (PRX1), which has 97% amino acid identity to HBP23. PRX1 was expressed in Escherichia coli and purified to homogeneity. Spectroscopic titration demonstrated that PRX1 binds heme with a 1:1 stoichiometry and a dissociation constant of 0.17 μM. UV-vis spectra of heme-PRX1 suggested that Cys52 is the axial ligand of ferric heme. PRX1 peroxidase activity was lost upon heme binding, reflecting the fact that Cys52 is not only the heme-binding site but also the active center of peroxidase activity. Interestingly, heme binding to PRX1 caused a decrease in the toxicity and degradation of heme, significantly suppressing H2O2-dependent heme peroxidase activity and degradation of PRX1-bound heme compared with that of free hemin. By virtue of its cytosolic abundance (∼20 μM), PRX1 thus functions as a scavenger of cytosolic hemin (dual role; Cys-dependent peroxidase activity and cytosolic heme scavenger. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Chloramines and hypochlorous acid oxidize erythrocyte peroxiredoxin 2.

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    Stacey, Melissa M; Peskin, Alexander V; Vissers, Margreet C; Winterbourn, Christine C

    2009-11-15

    Peroxiredoxin 2 (Prx2) is an abundant thiol protein that is readily oxidized in erythrocytes exposed to hydrogen peroxide. We investigated its reactivity in human erythrocytes with hypochlorous acid (HOCl) and chloramines, relevant oxidants in inflammation. Prx2 was oxidized to a disulfide-linked dimer by HOCl, glycine chloramine (GlyCl), and monochloramine (NH(2)Cl) in a dose-dependent manner. In the absence of added glucose, Prx2 and GSH showed similar sensitivities. Second-order rate constants for the reactions of Prx2 with NH(2)Cl and GlyCl were 1.5 x 10(4) and 8 M(-1) s(-1), respectively. The NH(2)Cl value is approximately 10 times higher than that for GSH, whereas Prx2 is approximately 30 times less sensitive than GSH to GlyCl. Thus, the relative sensitivity of Prx2 to GlyCl is greater in the erythrocyte. Oxidation of erythrocyte Prx2 and GSH was less in the presence of glucose, probably because of recycling. High doses of NH(2)Cl resulted in incomplete regeneration of reduced Prx2, suggesting impairment of the recycling mechanism. Our results show that, although HOCl and chloramines are less selective than H(2)O(2), they nevertheless oxidize Prx2. Exposure to these inflammatory oxidants will result in Prx2 oxidation and could compromise the erythrocyte's ability to resist damaging oxidative insult.

  6. Overexpression of peroxiredoxin I and thioredoxin1 in human breast carcinoma

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    Kim Il-Han

    2009-06-01

    Full Text Available Abstract Background Peroxiredoxins (Prxs are a novel group of peroxidases containing high antioxidant efficiency. The mammalian Prx family has six distinct members (Prx I-VI in various subcellular locations, including peroxisomes and mitochondria, places where oxidative stress is most evident. The function of Prx I in particular has been implicated in regulating cell proliferation, differentiation, and apoptosis. Since thioredoxin1 (Trx1 as an electron donor is functionally associated with Prx I, we investigated levels of expression of both Prx I and Trx1. Methods We investigated levels of expression of both Prx I and Trx1 in breast cancer by real-time polymerase chain reaction (RT-PCR and Western blot. Results Levels of messenger RNA (mRNA for both Prx I and Trx1 in normal human breast tissue were very low compared to other major human tissues, whereas their levels in breast cancer exceeded that in other solid cancers (colon, kidney, liver, lung, ovary, prostate, and thyroid. Among members of the Prx family (Prx I-VI and Trx family (Trx1, Trx2, Prx I and Trx1 were preferentially induced in breast cancer. Moreover, the expression of each was associated with progress of breast cancer and correlated with each other. Western blot analysis of different and paired breast tissues revealed consistent and preferential expression of Prx I and Trx1 protein in breast cancer tissue. Conclusion Prx I and Trx1 are overexpressed in human breast carcinoma and the expression levels are associated with tumor grade. The striking induction of Prx I and Trx1 in breast cancer may enable their use as breast cancer markers.

  7. Molecular cloning and characterization of a peroxiredoxin gene from the mole cricket, Gryllotalpa orientalis.

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    Kim, Iksoo; Lee, Kwang Sik; Hwang, Jae Sam; Ahn, Mi Young; Li, Jianhong; Sohn, Hung Dae; Jin, Byun Rae

    2005-04-01

    We report the cloning, expression and characterization of a cDNA encoding the antioxidant enzyme peroxiredoxin (Prx) from the mole cricket, Gryllotalpa orientalis. The G. orientalis Prx (GoPrx) cDNA contains an open reading frame of 660 bp encoding 220 amino acid residues and possesses one cysteine residue that is characteristic of the 1-Cys subgroup of the peroxiredoxin family. The deduced amino acid sequence of the GoPrx cDNA showed 69% identity to Drosophila melanogaster DPx-2540, 50% to D. melanogaster DPx-6005, and 47% to Glossina morsitans morsitans Prx. Phylogenetic analysis further confirmed a closer relationship of the deduced amino acid sequences of the GoPrx gene to the DPx-2540 within the 1-Cys Prx cluster. The cDNA encoding GoPrx was expressed as a 27-kDa polypeptide in baculovirus-infected insect Sf9 cells. The purified recombinant GoPrx was shown to reduce H(2)O(2) in the presence of electrons donated by dithiothreitol, but did not show the activity in the presence of thioredoxin as electron donor. Northern blot analysis revealed the presence of GoPrx transcripts in all tissues examined. When H(2)O(2) was injected into the body cavity of G. orientalis adult, GoPrx mRNA expression was up-regulated in the fat body tissues. Furthermore, the expression levels of GoPrx mRNA in the fat body were particularly high when G. orientalis adult was exposed at low (4 degrees C) and high (37 degrees C) temperatures, suggesting that the GoPrx seems to play a protective role against oxidative stress caused by temperature shock.

  8. Physiological Significance of Plant Peroxiredoxins and the Structure-Related and Multifunctional Biochemistry of Peroxiredoxin 1.

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    Lee, Eun Seon; Kang, Chang Ho; Park, Joung Hun; Lee, Sang Yeol

    2018-01-02

    Sessile plants respond to oxidative stress caused by internal and external stimuli by producing diverse forms of enzymatic and nonenzymatic antioxidant molecules. Peroxiredoxins (Prxs) in plants, including the Prx1, Prx5, Prx6, and PrxQ isoforms, constitute a family of antioxidant enzymes and play important functions in cells. Each Prx localizes to a specific subcellular compartment and has a distinct function in the control of plant growth, development, cellular metabolism, and various aspects of defense signaling. Recent Advances: Prx1, a typical Prx in plant chloroplasts, has redox-dependent multiple functions. It acts as a hydrogen peroxide (H2O2)-catalyzing peroxidase, a molecular chaperone, and a biological circadian marker. Prx1 undergoes a functional switching from a peroxidase to a molecular chaperone in response to oxidative stress, concomitant with the structural changes from a low-molecular-weight species to high-molecular-weight complexes mediated by the post-translational modification of its active site Cys residues. The redox status of the protein oscillates diurnally between hyperoxidation and reduction, showing a circadian rhythmic output. These dynamic structural and functional transformations mediate the effect of plant Prx1 on protecting plants from a myriad of harsh environmental stresses. The multifunctional diversity of plant Prxs and their roles in cellular defense signaling depends on their specific interaction partners, which remain largely unidentified. Therefore, the identification of Prx-interacting proteins is necessary to clarify their physiological significance. Since the functional specificity of the four plant Prx isoforms remains unclear, future studies should focus on investigating the physiological importance of each Prx isotype. Antioxid. Redox Signal. 00, 000-000.

  9. Identification and characterization of an atypical 2-cys peroxiredoxin from the silkworm, Bombyx mori.

    Science.gov (United States)

    Wang, Q; Zhou, Y; Chen, K; Ju, X

    2016-08-01

    Peroxiredoxins (Prxs) play an important role in the protection of insects against the toxicity of reactive oxygen species. Here, we identified and characterized a novel, atypical 2-cysteine (Cys) peroxiredoxin (BmPrx3) from an expressed sequence tag database in a lepidopteran insect, Bombyx mori. The BmPrx3 cDNA contained an open reading frame of 684 bp that encodes a 228-amino-acid protein with a calculated molecular mass of 25 kDa. Sequence comparison revealed that BmPrx3 belongs to the atypical 2-Cys Prxs. Quantitative real-time PCR revealed that BmPrx3 can be detected in all tissues and developmental stages. Recombinant BmPrx3 purified from Escherichia coli exhibited antioxidant activity that removed hydrogen peroxide and protected DNA from oxidative damage. Disc diffusion and viability assays revealed that recombinant BmPrx3 increased bacterial survival under H2 O2 -mediated oxidative stress. In addition, quantitative real-time PCR analysis indicated that BmPrx3 transcription levels were significantly increased in response to various oxidative stresses. Furthermore, BmPrx3 transcription levels in the midgut were regulated by bacterial infection. Taken together, these results suggest that BmPrx3 acts as an antioxidant enzyme to protect the silkworm from various oxidative stresses. © 2016 The Royal Entomological Society.

  10. A novel reaction of peroxiredoxin 4 towards substrates in oxidative protein folding.

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    Li Zhu

    Full Text Available Peroxiredoxin 4 (Prx4 is the only endoplasmic reticulum localized peroxiredoxin. It functions not only to eliminate peroxide but also to promote oxidative protein folding via oxidizing protein disulfide isomerase (PDI. In Prx4-mediated oxidative protein folding we discovered a new reaction that the sulfenic acid form of Prx4 can directly react with thiols in folding substrates, resulting in non-native disulfide cross-linking and aggregation. We also found that PDI can inhibit this reaction by exerting its reductase and chaperone activities. This discovery discloses an off-pathway reaction in the Prx4-mediated oxidative protein folding and the quality control role of PDI.

  11. A large mobility of hydrophilic molecules at the outmost layer controls the protein adsorption and adhering behavior with the actin fiber orientation of human umbilical vein endothelial cells (HUVEC).

    Science.gov (United States)

    Kakinoki, Sachiro; Seo, Ji-Hun; Inoue, Yuuki; Ishihara, Kazuhiko; Yui, Nobuhiko; Yamaoka, Tetsuji

    2013-01-01

    Adhesion behaviors of human umbilical vein endothelial cells (HUVECs) are interestingly affected by the mobility of hydrophilic chains on the material surfaces. Surfaces with different molecular mobilities were prepared using ABA-type block copolymers consisting polyrotaxane (PRX) or poly(ethylene glycol) (PEG) central block (A block), and amphiphilic anchoring B blocks of poly(2-methacryloyloxyethyl phosphorylcholine-co-n-butyl methacrylate) (PMB). Two different molecular mobilities of the PRX chains were designed by using normal α-cyclodextrin (α-CD) or α-CD whose hydroxyl groups were converted to methoxy groups in a given ratio to improve its molecular mobility (PRX-PMB and OMe-PRX-PMB). The surface mobility of these materials was assessed as the mobility factor (Mf), which is measured by quartz crystal microbalance with dissipation monitoring system. HUVECs adhered on OMe-PRX-PMB surface much more than PRX-PMB and PMB-block-PEG-block-PMB (PEG-PMB) surfaces. These different HUVEC adhesions were correlated with the density of cell-binding site of adsorbed fibronectin. In addition, the alignment of the actin cytoskeleton of adhered HUVECs was strongly suppressed on the PEG-PMB, PRX-PMB, and OMe-PRX-PMB in response to the increased Mf value. Remarkably, the HUVECs adhered on the OMe-PRX-PMB surface with much less actin organization. We concluded that not only the cell adhesion but also the cellular function are regulated by the molecular mobility of the outmost material surfaces.

  12. Functional characterization of peroxiredoxins from the human protozoan parasite Giardia intestinalis.

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    Daniela Mastronicola

    Full Text Available The microaerophilic protozoan parasite Giardia intestinalis, causative of one of the most common human intestinal diseases worldwide, infects the mucosa of the proximal small intestine, where it has to cope with O2 and nitric oxide (NO. Elucidating the antioxidant defense system of this pathogen lacking catalase and other conventional antioxidant enzymes is thus important to unveil novel potential drug targets. Enzymes metabolizing O2, NO and superoxide anion (O2 (-• have been recently reported for Giardia, but it is yet unknown how the parasite copes with H2O2 and peroxynitrite (ONOO(-. Giardia encodes two yet uncharacterized 2-cys peroxiredoxins (Prxs, GiPrx1a and GiPrx1b. Peroxiredoxins are peroxidases implicated in virulence and drug resistance in several parasitic protozoa, able to protect from nitroxidative stress and repair oxidatively damaged molecules. GiPrx1a and a truncated form of GiPrx1b (deltaGiPrx1b were expressed in Escherichia coli, purified and functionally characterized. Both Prxs effectively metabolize H2O2 and alkyl-hydroperoxides (cumyl- and tert-butyl-hydroperoxide in the presence of NADPH and E. coli thioredoxin reductase/thioredoxin as the reducing system. Stopped-flow experiments show that both proteins in the reduced state react with ONOO(- rapidly (k = 4×10(5 M(-1 s(-1 and 2×10(5 M(-1 s(-1 at 4°C, for GiPrx1a and deltaGiPrx1b, respectively. Consistent with a protective role against oxidative stress, expression of GiPrx1a (but not deltaGiPrx1b is induced in parasitic cells exposed to air O2 for 24 h. Based on these results, GiPrx1a and deltaGiPrx1b are suggested to play an important role in the antioxidant defense of Giardia, possibly contributing to pathogenesis.

  13. Genetic analysis of Runx2 function during intramembranous ossification.

    Science.gov (United States)

    Takarada, Takeshi; Nakazato, Ryota; Tsuchikane, Azusa; Fujikawa, Koichi; Iezaki, Takashi; Yoneda, Yukio; Hinoi, Eiichi

    2016-01-15

    Runt-related transcription factor 2 (Runx2) is an essential transcriptional regulator of osteoblast differentiation and its haploinsufficiency leads to cleidocranial dysplasia because of a defect in osteoblast differentiation during bone formation through intramembranous ossification. The cellular origin and essential period for Runx2 function during osteoblast differentiation in intramembranous ossification remain poorly understood. Paired related homeobox 1 (Prx1) is expressed in craniofacial mesenchyme, and Runx2 deficiency in cells of the Prx1 lineage (in mice referred to here as Runx2prx1 (-/-)) resulted in defective intramembranous ossification. Runx2 was heterogeneously expressed in Prx1-GFP(+) cells located at the intrasutural mesenchyme in the calvaria of transgenic mice expressing GFP under the control of the Prx1 promoter. Double-positive cells for Prx1-GFP and stem cell antigen-1 (Sca1) (Prx1(+)Sca1(+) cells) in the calvaria expressed Runx2 at lower levels and were more homogeneous and primitive than Prx1(+)Sca1(-) cells. Osterix (Osx) is another transcriptional determinant of osteoblast lineages expressed by osteoblast precursors; Osx is highly expressed by Prx1(-)Runx2(+) cells at the osteogenic front and on the surface of mineralized bone in the calvaria. Runx2 deficiency in cells of the Osx lineage (in mice referred to here as Runx2osx (-/-)) resulted in severe defects in intramembranous ossification. These findings indicate that the essential period of Runx2 function in intramembranous ossification begins at the Prx1(+)Sca1(+) mesenchymal stem cell stage and ends at the Osx(+)Prx1(-)Sca1(-) osteoblast precursor stage. © 2016. Published by The Company of Biologists Ltd.

  14. Circulating peroxiredoxin 4 and type 2 diabetes risk : the Prevention of Renal and Vascular Endstage Disease (PREVEND) study

    NARCIS (Netherlands)

    Abbasi, Ali; Corpeleijn, Eva; Gansevoort, Ron T; Gans, Rijk O B; Struck, Joachim; Schulte, Janin; Hillege, Hans L; van der Harst, Pim van der; Stolk, Ronald P; Navis, Gerarda; Bakker, Stephan J L

    2014-01-01

    AIMS/HYPOTHESIS: Oxidative stress plays a key role in the development of type 2 diabetes mellitus. We previously showed that the circulating antioxidant peroxiredoxin 4 (Prx4) is associated with cardiometabolic risk factors. We aimed to evaluate the association of Prx4 with type 2 diabetes risk in

  15. Chloroplast NADPH-Dependent Thioredoxin Reductase from Chlorella vulgaris Alleviates Environmental Stresses in Yeast Together with 2-Cys Peroxiredoxin

    Science.gov (United States)

    Machida, Takeshi; Ishibashi, Akiko; Kirino, Ai; Sato, Jun-ichi; Kawasaki, Shinji; Niimura, Youichi; Honjoh, Ken-ichi; Miyamoto, Takahisa

    2012-01-01

    Chloroplast NADPH-dependent thioredoxin reductase (NTRC) catalyzes the reduction of 2-Cys peroxiredoxin (2-Cys Prx) and, thus, probably functions as an antioxidant system. The functions of the enzyme in oxidative and salt stresses have been reported previously. We have previously identified and characterized NTRC in Chlorella vulgaris. In the present study, we isolated a full-length cDNA clone encoding 2-Cys Prx from C. vulgaris and investigated the involvement of Chlorella NTRC/2-Cys Prx system in several environmental stress tolerances by using yeast as a eukaryotic model. Deduced Chlorella 2-Cys Prx was homologous to those of chloroplast 2-Cys Prxs from plants, and two conserved cysteine residues were found in the deduced sequence. Enzyme assay showed that recombinant mature C. vulgaris NTRC (mCvNTRC) transferred electrons from NADPH to recombinant mature C. vulgaris 2-Cys Prx (mCvPrx), and mCvPrx decomposed hydrogen peroxide, tert-butyl hydroperoxide, and peroxynitrite by cooperating with mCvNTRC. Based on the results, the mCvNTRC/mCvPrx antioxidant system was identified in Chlorella. The antioxidant system genes were expressed in yeast separately or coordinately. Stress tolerances of yeast against freezing, heat, and menadione-induced oxidative stresses were significantly improved by expression of mCvNTRC, and the elevated tolerances were more significant when both mCvNTRC and mCvPrx were co-expressed. Our results reveal a novel feature of NTRC: it functions as an antioxidant system with 2-Cys Prx in freezing and heat stress tolerances. PMID:23029353

  16. Effects of xenon and hypothermia on cerebrovascular pressure reactivity in newborn global hypoxic–ischemic pig model

    Science.gov (United States)

    Chakkarapani, Elavazhagan; Dingley, John; Aquilina, Kristian; Osredkar, Damjan; Liu, Xun; Thoresen, Marianne

    2013-01-01

    Autoregulation of cerebral perfusion is impaired in hypoxic–ischemic encephalopathy. We investigated whether cerebrovascular pressure reactivity (PRx), an element of cerebral autoregulation that is calculated as a moving correlation coefficient between averages of intracranial and mean arterial blood pressure (MABP) with values between −1 and +1, is impaired during and after a hypoxic–ischemic insult (HI) in newborn pigs. Associations between end-tidal CO2, seizures, neuropathology, and PRx were investigated. The effect of hypothermia (HT) and Xenon (Xe) on PRx was studied. Pigs were randomized to Sham, and after HI to normothermia (NT), HT, Xe or xenon hypothermia (XeHT). We defined PRx >0.2 as peak and negative PRx as preserved. Neuropathology scores after 72 hours of survival was grouped as ‘severe' or ‘mild.' Secondary PRx peak during recovery, predictive of severe neuropathology and associated with insult severity (P=0.05), was delayed in HT (11.5 hours) than in NT (6.5 hours) groups. Seizures were associated with impaired PRx in NT pigs (P=0.0002), but not in the HT/XeHT pigs. PRx was preserved during normocapnia and impaired during hypocapnia. Xenon abolished the secondary PRx peak, increased (mean (95% confidence interval (CI)) MABP (6.5 (3.8, 9.4) mm Hg) and cerebral perfusion pressure (5.9 (2.9, 8.9) mm Hg) and preserved the PRx (regression coefficient, −0.098 (95% CI (−0.18, −0.01)), independent of the insult severity. PMID:23899927

  17. Molecular cloning of two novel peroxidases and their response to salt stress and salicylic acid in the living fossil Ginkgo biloba.

    Science.gov (United States)

    Novo-Uzal, Esther; Gutiérrez, Jorge; Martínez-Cortés, Teresa; Pomar, Federico

    2014-10-01

    Peroxidase isoenzymes play diverse roles in plant physiology, such as lignification and defence against pathogens. The actions and regulation of many peroxidases are not known with much accuracy. A number of studies have reported direct involvement of peroxidase isoenzymes in the oxidation of monolignols, which constitutes the last step in the lignin biosynthesis pathway. However, most of the available data concern only peroxidases and lignins from angiosperms. This study describes the molecular cloning of two novel peroxidases from the 'living fossil' Ginkgo biloba and their regulation by salt stress and salicylic acid. Suspension cell cultures were used to purify peroxidases and to obtain the cDNAs. Treatments with salicylic acid and sodium chloride were performed and peroxidase activity and gene expression were monitored. A novel peroxidase was purified, which preferentially used p-hydroxycinnamyl alcohols as substrates and was able to form dehydrogenation polymers in vitro from coniferyl and sinapyl alcohols. Two peroxidase full-length cDNAs, GbPrx09 and GbPrx10, were cloned. Both peroxidases showed high similarity to other basic peroxidases with a putative role in cell wall lignification. Both GbPrx09 and GbPrx10 were expressed in leaves and stems of the plant. Sodium chloride enhanced the gene expression of GbPrx09 but repressed GbPrx10, whereas salicylic acid strongly repressed both GbPrx09 and GbPrx10. Taken together, the data suggest the participation of GbPrx09 and GbPrx10 in the developmental lignification programme of the cell wall. Both peroxidases possess the structural characteristics necessary for sinapyl alcohol oxidation. Moreover, GbPrx09 is also involved in lignification induced by salt stress, while salicylic acid-mediated lignification is not a result of GbPrx09 and GbPrx10 enzymatic activity. © The Author 2014. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email

  18. Expression, purification and characterization of an atypical 2-Cys peroxiredoxin from the silkworm, Bombyx mori.

    Science.gov (United States)

    Zhang, L; Lu, Z

    2015-04-01

    Peroxiredoxins (Prxs) play important roles in protecting organisms against damage caused by reactive oxygen species (ROS). In this study, we cloned a cDNA of Bombyx mori peroxiredoxin 5 (BmPrx5), which contained a 565-bp open reading frame for a 188-residue protein. Sequence analysis indicated that BmPrx5 belongs to the atypical 2-Cys peroxiredoxin family. Recombinant BmPrx5 purified from Escherichia coli showed antioxidant activity that removes H2 O2 and protects DNA from oxidative damage. Quantitative real-time PCR showed that the level of BmPrx5 mRNA in haemocytes increased early and decreased by 24 h after injection of H2 O2 whereas, in the fat body, the transcript level decreased at 6 h and increased at 12 h. Pseudomonas aeruginosa and Staphylococcus aureus infection resulted in higher levels of H2 O2 in the haemolymph and of BmPrx5 mRNA in haemocytes at 8 h postinfection. These data suggest that BmPrx5 acts as an antioxidant enzyme to protect the silkworm from oxidative damage induced by bacterial infection. Further study is needed to elucidate the exact role of BmPrx5 in the silkworm immune system. © 2014 The Royal Entomological Society.

  19. Versatile synthesis of end-reactive polyrotaxanes applicable to fabrication of supramolecular biomaterials

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    Atsushi Tamura

    2016-12-01

    Full Text Available Cyclodextrin (CD-threaded polyrotaxanes (PRXs with reactive functional groups at the terminals of the axle polymers are attractive candidates for the design of supramolecular materials. Herein, we describe a novel and simple synthetic method for end-reactive PRXs using bis(2-amino-3-phenylpropyl poly(ethylene glycol (PEG-Ph-NH2 as an axle polymer and commercially available 4-substituted benzoic acids as capping reagents. The terminal 2-amino-3-phenylpropyl groups of PEG-Ph-NH2 block the dethreading of the α-CDs after capping with 4-substituted benzoic acids. By this method, two series of azide group-terminated polyrotaxanes (benzylazide: PRX-Bn-N3, phenylazide: PRX-Ph-N3, were synthesized for functionalization via click reactions. The PRX-Bn-N3 and PRX-Ph-N3 reacted quickly and efficiently with p-(tert-butylphenylacetylene via copper-catalyzed click reactions. Additionally, the terminal azide groups of the PRX-Bn-N3 could be modified with dibenzylcyclooctyne (DBCO-conjugated fluorescent molecules via a copper-free click reaction; this fluorescently labeled PRX was utilized for intracellular fluorescence imaging. The method of synthesizing end-reactive PRXs described herein is simple and versatile for the design of diverse functional PRXs and can be applied to the fabrication of PRX-based supramolecular biomaterials.

  20. Disabling Mitochondrial Peroxide Metabolism via Combinatorial Targeting of Peroxiredoxin 3 as an Effective Therapeutic Approach for Malignant Mesothelioma.

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    Brian Cunniff

    Full Text Available Dysregulation of signaling pathways and energy metabolism in cancer cells enhances production of mitochondrial hydrogen peroxide that supports tumorigenesis through multiple mechanisms. To counteract the adverse effects of mitochondrial peroxide many solid tumor types up-regulate the mitochondrial thioredoxin reductase 2--thioredoxin 2 (TRX2--peroxiredoxin 3 (PRX3 antioxidant network. Using malignant mesothelioma cells as a model, we show that thiostrepton (TS irreversibly disables PRX3 via covalent crosslinking of peroxidatic and resolving cysteine residues in homodimers, and that targeting the oxidoreductase TRX2 with the triphenylmethane gentian violet (GV potentiates adduction by increasing levels of disulfide-bonded PRX3 dimers. Due to the fact that activity of the PRX3 catalytic cycle dictates the rate of adduction by TS, immortalized and primary human mesothelial cells are significantly less sensitive to both compounds. Moreover, stable knockdown of PRX3 reduces mesothelioma cell proliferation and sensitivity to TS. Expression of catalase in shPRX3 mesothelioma cells restores defects in cell proliferation but not sensitivity to TS. In a SCID mouse xenograft model of human mesothelioma, administration of TS and GV together reduced tumor burden more effectively than either agent alone. Because increased production of mitochondrial hydrogen peroxide is a common phenotype of malignant cells, and TS and GV are well tolerated in mammals, we propose that targeting PRX3 is a feasible redox-dependent strategy for managing mesothelioma and other intractable human malignancies.

  1. Serum peroxiredoxin 4: a marker of oxidative stress associated with mortality in type 2 diabetes (ZODIAC-28.

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    Esther G Gerrits

    Full Text Available BACKGROUND: Oxidative stress plays an underlying pathophysiologic role in the development of diabetes complications. The aim of this study was to investigate peroxiredoxin 4 (Prx4, a proposed novel biomarker of oxidative stress, and its association with and capability as a biomarker in predicting (cardiovascular mortality in type 2 diabetes mellitus. METHODS: Prx4 was assessed in baseline serum samples of 1161 type 2 diabetes patients. Cox proportional hazard models were used to evaluate the relationship between Prx4 and (cardiovascular mortality. Risk prediction capabilities of Prx4 for (cardiovascular mortality were assessed with Harrell's C statistic, the integrated discrimination improvement and net reclassification improvement. RESULTS: Mean age was 67 and the median diabetes duration was 4.0 years. After a median follow-up period of 5.8 years, 327 patients died; 137 cardiovascular deaths. Prx4 was associated with (cardiovascular mortality. The Cox proportional hazard models added the variables: Prx4 (model 1; age and gender (model 2, and BMI, creatinine, smoking, diabetes duration, systolic blood pressure, cholesterol-HDL ratio, history of macrovascular complications, and albuminuria (model 3. Hazard ratios (HR (95% CI for cardiovascular mortality were 1.93 (1.57 - 2.38, 1.75 (1.39 - 2.20, and 1.63 (1.28 - 2.09 for models 1, 2 and 3, respectively. HR for all-cause mortality were 1.73 (1.50 - 1.99, 1.50 (1.29 - 1.75, and 1.44 (1.23 - 1.67 for models 1, 2 and 3, respectively. Addition of Prx4 to the traditional risk factors slightly improved risk prediction of (cardiovascular mortality. CONCLUSIONS: Prx4 is independently associated with (cardiovascular mortality in type 2 diabetes patients. After addition of Prx4 to the traditional risk factors, there was a slightly improvement in risk prediction of (cardiovascular mortality in this patient group.

  2. Autoregulation monitoring and outcome prediction in neurocritical care patients: Does one index fit all?

    Science.gov (United States)

    Schmidt, Bernhard; Reinhard, Matthias; Lezaic, Vesna; McLeod, Damian D; Weinhold, Marco; Mattes, Heinz; Klingelhöfer, Jürgen

    2016-06-01

    Indexes PRx and Mx have been formerly introduced to assess cerebral autoregulation and have been shown to be associated with 3-month clinical outcome. In a mixed cohort of neurocritical care patients, we retrospectively investigated the impact of selected clinical characteristics on this association. Forty-one patients (18-77 years) with severe traumatic (TBI, N = 20) and non-traumatic (N = 21) brain injuries were studied. Cerebral blood flow velocity, arterial blood pressure and intracranial pressure were repeatedly recorded during 1-h periods. Calculated PRx and Mx were correlated with 3-month clinical outcome score of modified Rankin Scale (mRS) in different subgroups with specific clinical characteristics. Both PRx and Mx correlated significantly with outcome (PRx: r = 0.38, p < 0.05; AUC = 0.64, n.s./Mx: r = 0.48, p < 0.005; AUC = 0.80, p < 0.005) in the overall group, and in patients with hemicraniectomy (N = 17; PRx: r = 0.73, p < 0.001; AUC = 0.89, p < 0.01/Mx: r = 0.69, p < 0.005; AUC = 0.87, p < 0.05). Mx, not PRx, correlated significantly with mRS in patients with heart failure (N = 17; r = 0.69, p < 0.005; AUC = 0.92, p < 0.005), and in non-traumatic patients (r = 0.49, p < 0.05; AUC = 0.79, p < 0.05). PRx, not Mx, correlated significantly with mRS in TBI patients (r = 0.63, p < 0.01; AUC = 0.89, p < 0.01). Both indexes did not correlate with mRS in diabetes patients (N = 15), PRx failed in hypocapnic patients (N = 26). Both PRx and Mx were significantly associated with 3-month clinical outcome, even in patients with hemicraniectomy. PRx was more appropriate for TBI patients, while Mx was better suited for non-traumatic patients and patients with heart failure. Prognostic values of indexes were affected by diabetes (both Mx and PRx) and hypocapnia (PRx only).

  3. Regulatory redox state in tree seeds

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    Ewelina Ratajczak

    2017-12-01

    Full Text Available Peroxiredoxins (Prx are important regulators of the redox status of tree seeds during maturation and long-term storage. Thioredoxins (Trx are redox transmitters and thereby regulate Prx activity. Current research is focused on the association of Trx with Prx in tree seeds differing in the tolerance to desiccation. The results will allow for better understanding the regulation of the redox status in orthodox, recalcitrant, and intermediate seeds. The findings will also elucidate the role of the redox status during the loss of viability of sensitive seeds during drying and long-term storage.

  4. Acid stress response and protein induction in Campylobacter jejuni isolates with different acid tolerance

    DEFF Research Database (Denmark)

    Birk, Tina; Wik, Monica Takamiya; Lametsch, René

    2012-01-01

    (Cj0706), molybdenum cofactor biosynthesis protein (MogA), and bacterioferritin (Dps). Strain and acid type dependent differences in the level of response were observed. For strain NCTC 11168, the induced proteins and the regulator fur were analysed at the transcriptomic level using qRT-PCR....... In this transcriptomic analysis, only up-regulation of trxB and p19 was observed. CONCLUSIONS: A defined medium that supports the growth of a range of Campylobacter strains and suitable for proteomic analysis was developed. Mainly proteins normally involved in iron control and oxidative stress defence were induced...

  5. Overproduction, purification, crystallization and preliminary X-ray analysis of the peroxiredoxin domain of a larger natural hybrid protein from Thermotoga maritima

    Energy Technology Data Exchange (ETDEWEB)

    Barbey, Carole, E-mail: carole.barbey@smbh.univ-paris13.fr [Laboratoire de Biophysique Moléculaire, Cellulaire et Tissulaire, UMR 7033, Université Paris 13, UFR SMBH, 74 Rue Marcel Cachin, 93017 Bobigny CEDEX (France); Rouhier, Nicolas [Unité Mixte de Recherches 1136 INRA UHP (Interaction Arbres Microorganismes), IFR 110, Nancy Université BP 239, 54506 Vandoeuvre-lès-Nancy CEDEX (France); Haouz, Ahmed [Plate-forme de Cristallogenèse et Diffraction des Rayons X, Institut Pasteur, 25 Rue du Dr Roux, 75724 Paris (France); Navaza, Alda [Laboratoire de Biophysique Moléculaire, Cellulaire et Tissulaire, UMR 7033, Université Paris 13, UFR SMBH, 74 Rue Marcel Cachin, 93017 Bobigny CEDEX (France); Jacquot, Jean-Pierre [Unité Mixte de Recherches 1136 INRA UHP (Interaction Arbres Microorganismes), IFR 110, Nancy Université BP 239, 54506 Vandoeuvre-lès-Nancy CEDEX (France); Laboratoire de Biophysique Moléculaire, Cellulaire et Tissulaire, UMR 7033, Université Paris 13, UFR SMBH, 74 Rue Marcel Cachin, 93017 Bobigny CEDEX (France)

    2008-01-01

    Crystals of the peroxiredoxin domain of a larger natural hybrid protein from T. maritima were obtained which diffracted to 2.9 Å resolution on a synchrotron source. Thermotoga maritima contains a natural hybrid protein constituted of two moieties: a peroxiredoxin domain at the N-terminus and a nitroreductase domain at the C-terminus. The peroxiredoxin (Prx) domain has been overproduced and purified from Escherichia coli cells. The recombinant Prx domain, which is homologous to bacterial Prx BCP and plant Prx Q, folds properly into a stable protein that possesses biological activity. The recombinant protein was crystallized and synchrotron data were collected to 2.9 Å resolution. The crystals belonged to the tetragonal space group I422, with unit-cell parameters a = b = 176.67, c = 141.20 Å.

  6. X-Ray diffraction, spectroscopy and thermochemical characterization of the pharmaceutical paroxetine nitrate salt

    Science.gov (United States)

    Carvalho, Paulo S.; de Melo, Cristiane C.; Ayala, Alejandro P.; Ellena, Javier

    2016-08-01

    A comprehensive solid state study of Paroxetine nitrate hydrate, (PRX+·NO3-)H2O, is reported. This salt was characterized by a combination of methods, including Single crystal X-ray diffraction, Thermal analysis, Fourier transform infrared spectroscopy (FTIR) and Solubility measurements. (PRX+·NO3-)H2O crystallizes in the monoclinic C2 space group (Z‧ = 1) and its packing was analyzed in details, showing that the main supramolecular motif consists in a C22(4) chain formed by charge-assisted N+-H⋯O- hydrogen bonds. The salt formation and conformation features were also accuracy established via FTIR spectra. In comparison with the pharmaceutical approved (PRX+ṡCl-)ṡ0.5H2O, (PRX+ṡNO3-)ṡH2O showed a decrease of 24 °C in the drug melting peak and a slight reduction in its water solubility value.

  7. Genome-wide analysis of putative peroxiredoxin in unicellular and filamentous cyanobacteria

    Directory of Open Access Journals (Sweden)

    Cui Hongli

    2012-11-01

    Full Text Available Abstract Background Cyanobacteria are photoautotrophic prokaryotes with wide variations in genome sizes and ecological habitats. Peroxiredoxin (PRX is an important protein that plays essential roles in protecting own cells against reactive oxygen species (ROS. PRXs have been identified from mammals, fungi and higher plants. However, knowledge on cyanobacterial PRXs still remains obscure. With the availability of 37 sequenced cyanobacterial genomes, we performed a comprehensive comparative analysis of PRXs and explored their diversity, distribution, domain structure and evolution. Results Overall 244 putative prx genes were identified, which were abundant in filamentous diazotrophic cyanobacteria, Acaryochloris marina MBIC 11017, and unicellular cyanobacteria inhabiting freshwater and hot-springs, while poor in all Prochlorococcus and marine Synechococcus strains. Among these putative genes, 25 open reading frames (ORFs encoding hypothetical proteins were identified as prx gene family members and the others were already annotated as prx genes. All 244 putative PRXs were classified into five major subfamilies (1-Cys, 2-Cys, BCP, PRX5_like, and PRX-like according to their domain structures. The catalytic motifs of the cyanobacterial PRXs were similar to those of eukaryotic PRXs and highly conserved in all but the PRX-like subfamily. Classical motif (CXXC of thioredoxin was detected in protein sequences from the PRX-like subfamily. Phylogenetic tree constructed of catalytic domains coincided well with the domain structures of PRXs and the phylogenies based on 16s rRNA. Conclusions The distribution of genes encoding PRXs in different unicellular and filamentous cyanobacteria especially those sub-families like PRX-like or 1-Cys PRX correlate with the genome size, eco-physiology, and physiological properties of the organisms. Cyanobacterial and eukaryotic PRXs share similar conserved motifs, indicating that cyanobacteria adopt similar catalytic

  8. Genome-wide analysis of putative peroxiredoxin in unicellular and filamentous cyanobacteria

    Science.gov (United States)

    2012-01-01

    Background Cyanobacteria are photoautotrophic prokaryotes with wide variations in genome sizes and ecological habitats. Peroxiredoxin (PRX) is an important protein that plays essential roles in protecting own cells against reactive oxygen species (ROS). PRXs have been identified from mammals, fungi and higher plants. However, knowledge on cyanobacterial PRXs still remains obscure. With the availability of 37 sequenced cyanobacterial genomes, we performed a comprehensive comparative analysis of PRXs and explored their diversity, distribution, domain structure and evolution. Results Overall 244 putative prx genes were identified, which were abundant in filamentous diazotrophic cyanobacteria, Acaryochloris marina MBIC 11017, and unicellular cyanobacteria inhabiting freshwater and hot-springs, while poor in all Prochlorococcus and marine Synechococcus strains. Among these putative genes, 25 open reading frames (ORFs) encoding hypothetical proteins were identified as prx gene family members and the others were already annotated as prx genes. All 244 putative PRXs were classified into five major subfamilies (1-Cys, 2-Cys, BCP, PRX5_like, and PRX-like) according to their domain structures. The catalytic motifs of the cyanobacterial PRXs were similar to those of eukaryotic PRXs and highly conserved in all but the PRX-like subfamily. Classical motif (CXXC) of thioredoxin was detected in protein sequences from the PRX-like subfamily. Phylogenetic tree constructed of catalytic domains coincided well with the domain structures of PRXs and the phylogenies based on 16s rRNA. Conclusions The distribution of genes encoding PRXs in different unicellular and filamentous cyanobacteria especially those sub-families like PRX-like or 1-Cys PRX correlate with the genome size, eco-physiology, and physiological properties of the organisms. Cyanobacterial and eukaryotic PRXs share similar conserved motifs, indicating that cyanobacteria adopt similar catalytic mechanisms as eukaryotes. All

  9. Learning SAS’s Perl Regular Expression Matching the Easy Way: By Doing

    Science.gov (United States)

    2015-01-12

    WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) USAF School of Aerospace Medicine Aeromedical Research Department 2510 Fifth...regex_learning_tool allows both beginner and expert to efficiently practice PRX matching by selecting and processing only the match records that the user is interested...perl regular expression and/or source string. The regex_learning_tool allows both beginner and expert to efficiently practice PRX matching by

  10. Kinetic studies of peroxiredoxin 6 from Arenicola marina: rapid oxidation by hydrogen peroxide and peroxynitrite but lack of reduction by hydrogen sulfide.

    Science.gov (United States)

    Loumaye, Eléonore; Ferrer-Sueta, Gerardo; Alvarez, Beatriz; Rees, Jean-François; Clippe, André; Knoops, Bernard; Radi, Rafael; Trujillo, Madia

    2011-10-01

    Arenicola marina lives in marine environments where hydrogen peroxide concentrations reach micromolar levels. The annelid also forms reactive species through metabolic pathways. Its antioxidant systems include a cytosolic peroxiredoxin, peroxiredoxin 6 (AmPrx6 or AmPRDX6) that shows high homology to the mammalian 1-Cys peroxiredoxin. Previous work confirmed the peroxidase activity of AmPrx6 in the presence of dithiotreitol. Herein, we performed an in vitro kinetic characterization of the recombinant enzyme. AmPrx6 reduced hydrogen peroxide and peroxynitrite with rate constants of 1.1×10(7) and 2×10(6)M(-1)s(-1), respectively, at pH 7.4 and 25°C. Reduction of tert-butyl hydroperoxide was slower. The pK(a) of the peroxidatic thiol of AmPrx6 was determined as 5.1±0.2, indicating that it exists as thiolate, the reactive species, at physiological pH. The reductive part of the catalytic cycle was also explored. Hydrogen sulfide, present in millimolar concentrations in marine sediments where the annelid lives and that is able to reduce the mammalian 1-Cys peroxiredoxin, did not support AmPrx6 peroxidase activity. The enzyme was not reduced by other potential physiological reductants tested. Our data indicate that in this annelid, Prx6 could contribute to peroxide detoxification in the presence of a so far unidentified reducing counterpart. Copyright © 2011 Elsevier Inc. All rights reserved.

  11. Characterization and expression analysis of peroxiredoxin family genes from the silkworm Bombyx mori in response to phoxim and chlorpyrifos.

    Science.gov (United States)

    Shi, Gui-Qin; Zhang, Ze; Jia, Kun-Lun; Zhang, Kun; An, Dong-Xu; Wang, Gang; Zhang, Bao-Long; Yin, He-Nan

    2014-09-01

    The organophosphorus pesticide poisoning of the silkworm Bombyx mori is one of the major events causing serious damage to sericulture. Some antioxidant enzymes play roles in regulating generation of reactive oxygen species (ROS) by pesticides including phoxim and chlorpyrifos, but relatively little is known about their effects on the silkworm peroxiredoxin family genes. Here, five peroxiredoxin (Prx) genes have been identified in silkworm genome, and Prx genes of silkworm and mammalian homologs have apparent ortholog relationship. Based on the genomic DNA sequence, putative 5'-flanking region of five BmPrxs were obtained and the transcription factor binding sites were predicted. Their expression profiles exposed to different concentrations of phoxim and chlorpyrifos for 24 h, 48 h and 72 h in midgut of silkworm were investigated using quantitative RT-PCR (qRT-PCR). The results showed that five BmPrxs and dual oxidase (BmDUOX) gene were all expressed in midgut of silkworm. After feeding with 0.375 mg/L and 0.75 mg/L phoxim, the transcription levels of BmPrx3 and BmPrx5 that can be located in mitochondria reached their peak levels at an early time point (24h). However, the transcription levels of BmPrx4 and BmPrx6 that can be addressed to secrete from the cell and cytosol, respectively, reached their peak levels at a later time point (72 h). Similar to expose to phoxim, the transcription levels of BmPrx3 and BmPrx5 that can be located in mitochondria reached their peak levels at an early time point (24 h) under chlorpyrifos stress. However, the transcription levels of BmPrx4 and BmPrx6 that can be addressed to secrete from the cell and cytosol, respectively, reached their peak levels at a later time point (72 h) under chlorpyrifos stress. These results revealed that BmPrxs that can be located in mitochondria were able to protect cells even more efficiently than cytosolic from an oxidative stress caused by OP. In addition, BmDUOX was also induced by phomix and

  12. Role of reactive oxygene species, peroxiredoxins and thioredoxins in reaction of plants to hypergravity and oxidative stresses

    Science.gov (United States)

    Jadko, Sergiy

    Early increasing of reactive oxygen species (ROS) concentration, including H2O2, occur in plant cells under various impacts and these ROS can function as signaling molecules in starting of cell stress responses. Peroxiredoxins (Prx) and thioredoxins (Trx) are significant cell ROS/H2O2 sensors and transmitters. Prx besides its antioxidant activity, participate in creating of stress redox signals by destroying of H2O2 and reducing of Trx. Than these reduced Trx lead to activation of various redox sensitive proteins, transcription factors and MAP kinases. This study aimed to investigate early increasing of ROS and H2O2 contents and Prx and Trx activities in pea roots and arabidopsis tissue culture cells under hypergravity and oxidative stresses. Pea roots of 3-5 days old seedlings and 12 days old tissue culture of Arabidopsis thaliana from leaves were studied. Pea seedlings were grown on wet filter paper and the tissue culture was grown on MS medium in dark conditions under 24oC. Hypergravity stress was induced by centrifugation at 15 g. Chemiluminescence (ChL) intensity for ROS concentration, H2O2 content and Prx and Trx activities were determined. All experiments were repeated by 3-4 times. Early increasing of ChL intensity and H2O2 content in the pea roots and arabidopsis tissue culture cells took place under hypergravity and oxidative stresses and its were higher corresponding controls on average on 25, 21 and 17 percents to 30, 60 and 90 min. At the same time Prx and Trx activities increased on 7, 13 and 16 percents. Thus under hypergravity and oxidative stresses in both investigated plants take place early increasing of ROS and H2O2 contents which as second messengers can lead to ROS/H2O2-dependent increasing of Prx and Trx activities with creating of H2O2-Prx-Trx signaling pathway.

  13. Increase in expression levels and resistance to sulfhydryl oxidation of peroxiredoxin isoforms in amyloid beta-resistant nerve cells.

    Science.gov (United States)

    Cumming, Robert C; Dargusch, Richard; Fischer, Wolfgang H; Schubert, David

    2007-10-19

    Peroxiredoxins (Prxs) are a ubiquitously expressed family of thiol peroxidases that reduce hydrogen peroxide, peroxynitrite, and hydroperoxides using a highly conserved cysteine. There is substantial evidence that oxidative stress elicited by amyloid beta (Abeta) accumulation is a causative factor in the pathogenesis of Alzheimer disease (AD). Here we show that Abeta-resistant PC12 cell lines exhibit increased expression of multiple Prx isoforms with reduced cysteine oxidation. Abeta-resistant PC12 cells also display higher levels of thioredoxin and thioredoxin reductase, two enzymes critical for maintaining Prx activity. PC12 cells and rat primary hippocampal neurons transfected with wild type Prx1 exhibit increased Abeta resistance, whereas mutant Prx1, lacking a catalytic cysteine, confers no protection. Using an antibody that specifically recognizes sulfinylated and sulfonylated Prxs, it is demonstrated that primary rat cortical nerve cells exposed to Abeta display a time-dependent increase in cysteine oxidation of the catalytic site of Prxs that can be blocked by the addition of the thiol-antioxidant N-acetylcysteine. In support of previous findings, expression of Prx1 is higher in post-mortem human AD cortex tissues than in age-matched controls. In addition, two-dimensional gel electrophoresis and mass spectrometry analysis revealed that Prx2 exists in a more oxidized state in AD brains than in control brains. These findings suggest that increased Prx expression and resistance to sulfhydryl oxidation in Abeta-resistant nerve cells is a compensatory response to the oxidative stress initiated by chronic pro-oxidant Abeta exposure.

  14. A plant cell-expressed recombinant anti-TNF fusion protein is biologically active in the gut and alleviates immune-mediated hepatitis and colitis.

    Science.gov (United States)

    Ilan, Yaron; Gingis-Velitski, Svetlana; Ben Ya'aco, Ami; Shabbat, Yehudit; Zolotarov, Lidya; Almon, Einat; Shaaltiel, Yoseph

    2017-03-01

    The orally administered BY-2 plant cell-expressed recombinant anti-TNF fusion protein (PRX-106) (n=6) consists of the soluble form of the human TNF receptor (TNFR) fused to the Fc component of a human antibody IgG1 domain. To evaluate the immune modulatory effect of the oral administration of plant cells expressing PRX-106. Mice treated with Concanavalin A (ConA) to induce immune hepatitis was orally treated with cells expressing PRX-106 containing 0.5 or 5μg PRX 106. In the colitis model, TNBS-colitis was induced in mice followed by the oral administration of plant cells expressing PRX-106. The immune modulatory effect was determined through follow-up to assess the clinical effect, histology, and serum cytokine levels and by FACS analysis for lymphocyte subsets. The oral administration of BY-2 cells expressing PRX-106 alleviated immune-mediated liver injury. Serum AST and ALT levels decreased and were comparable to those of mice that had received high-dose steroids. The beneficial effect was also observed as a marked decrease in hepatic necrosis. In the colitis model, the oral administration of BY-2 plant cells expressing PRX-106 alleviated weight loss associated with immune-mediated colitis and improved bowel histology. A reduction in I-IkB-alpha phosphorylation in treated mice was also observed. These effects were associated with a significant alteration in the distribution of CD4+CD25+FOXP3+ cells. Plant cells expressing recombinant anti-TNF fusion protein show biological activity when orally administered, exerting an immune modulatory effect through the alleviation of immune-mediated hepatitis and immune-mediated colitis. Copyright © 2016 Elsevier GmbH. All rights reserved.

  15. Mutational analysis of Peroxiredoxin IV: exclusion of a positional candidate for multinodular goitre

    Directory of Open Access Journals (Sweden)

    Bonifazi Emanuela

    2002-07-01

    Full Text Available Abstract Background Multinodular goitre (MNG is a common disorder characterised by an enlargement of the thyroid, occurring as a compensatory response to hormonogenesis impairment. The incidence of MNG is dependent on sex (female:male ratio 5:1 and several reports have documented a genetic basis for the disease. Last year we mapped a MNG locus to chromosome Xp22 in a region containing the peroxiredoxin IV (Prx-IV gene. Since Prx-IV is involved in the removal of H2O2 in thyroid cells, we hypothesize that mutations in Prx-IV gene are involved in pathogenesis of MNG. Methods Four individuals (2 affected, 2 unrelated unaffected were sequenced using automated methods. All individuals were originated from the original three-generation Italian family described in previous studies. A Southern blot analysis using a Prx-IV full-length cDNA as a probe was performed in order to exclude genomic rearrangements and/or intronic mutations. In addition a RT-PCR of PRX-IV was performed in order to investigate expression alterations. Results No causative mutations were found. Two adjacent nucleotide substitutions were detected within introns 1 and 4. These changes were also detected in unaffected individuals, suggesting that they were innocuous polymorphisms. No gross genomic rearrangements and/or restriction fragment alterations were observed on Southern analysis. Finally, using RT-PCR from tissue-specific RNA, no differences of PRX-IV expression-levels were detected between affected and unaffected samples. Conclusions Based on sequence and genomic analysis, Prx-IV is very unlikely to be the MNG2 gene.

  16. An oral administration of a recombinant anti-TNF fusion protein is biologically active in the gut promoting regulatory T cells: Results of a phase I clinical trial using a novel oral anti-TNF alpha-based therapy.

    Science.gov (United States)

    Almon, Einat; Khoury, Tawfik; Drori, Ariel; Gingis-Velitski, Svetlana; Alon, Sari; Chertkoff, Raul; Mushkat, Mordechai; Shaaltiel, Yoseph; Ilan, Yaron

    2017-07-01

    An orally administered BY-2 plant cell-expressed recombinant anti-TNF fusion protein (PRX-106) consists of the soluble form of the human TNF receptor (TNFR) fused to the Fc component of a human IgG1 domain. Aim This study aim at determining the safety and the immune modulatory effect of an oral administration of PRX-106 in humans. Three different doses (2, 8 or 16mg/day) of PRX-106 were orally administered for five consecutive days in 14 healthy volunteered participants. Subjects were followed for safety parameters and for an effect on T lymphocytes subsets and cytokine levels. An oral administration of PRX-106 was safe and well tolerated. The PK study showed that PRX106 is not absorbed. No effect on white blood cells and lymphocytes counts were noted. A dose dependent effect was noted on systemic lymphocytes. The oral administration of all three dosages was associated with an increase in CD4+CD25+ and CD8+CD25+ subset of suppressor lymphocytes. A marked increase in CD4+CD25+FoxP3 regulatory T cells was noted in the 8mg treated group. In addition, NKT regulatory cells, CD3+CD69+ and CD4+CD62 lymphocyte subsets increased with treatment. No changes in serum TNF alpha were observed. An oral administration of the non-absorbable recombinant anti-TNF fusion protein, PRX-106, is safe, not associated with immune suppression, while inducing a favorable anti-inflammatory immune modulation. The PRX-106 may provide a safe orally administered effective anti-TNF alpha-based immune therapy for inflammatory bowel diseases and non-alcoholic steatohepatitis, as well as other autoimmune, TNF-mediated diseases. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Mitochondrial H2O2 signaling is controlled by the concerted action of peroxiredoxin III and sulfiredoxin: Linking mitochondrial function to circadian rhythm.

    Science.gov (United States)

    Rhee, Sue Goo; Kil, In Sup

    2016-11-01

    Mitochondria produce hydrogen peroxide (H2O2) during energy metabolism in most mammalian cells as well as during the oxidation of cholesterol associated with the synthesis of steroid hormones in steroidogenic cells. Some of the H2O2 produced in mitochondria is released into the cytosol, where it serves as a key regulator of various signaling pathways. Given that mitochondria are equipped with several H2O2-eliminating enzymes, however, it had not been clear how mitochondrial H2O2 can escape destruction by these enzymes for such release. Peroxiredoxin III (PrxIII) is the most abundant and efficient H2O2-eliminating enzyme in mitochondria of most cell types. We found that PrxIII undergoes reversible inactivation through hyperoxidation of its catalytic cysteine residue to cysteine sulfinic acid, and that release of mitochondrial H2O2 likely occurs as a result of such PrxIII inactivation. The hyperoxidized form of PrxIII (PrxIII-SO2H) is reduced and reactivated by sulfiredoxin (Srx). We also found that the amounts of PrxIII-SO2H and Srx undergo antiphasic circadian oscillation in mitochondria of the adrenal gland, heart, and brown adipose tissue of mice maintained under normal conditions. Cytosolic Srx was found to be imported into mitochondria via a mechanism that requires formation of a disulfide-linked complex with heat shock protein 90, which is likely promoted by H2O2 released from mitochondria. The imported Srx was found to be degraded by Lon protease in a manner dependent on PrxIII hyperoxidation state. The coordinated import and degradation of Srx underlie Srx oscillation and consequent PrxIII-SO2H oscillation in mitochondria. The rhythmic change in the amount of PrxIII-SO2H suggests that mitochondrial release of H2O2 is also likely a circadian event that conveys temporal information on steroidogenesis in the adrenal gland and on energy metabolism in heart and brown adipose tissue to cytosolic signaling pathways. Copyright © 2016. Published by Elsevier Inc.

  18. Neuroprotective effect of a novel gastrodin derivative against ischemic brain injury: involvement of peroxiredoxin and TLR4 signaling inhibition

    Science.gov (United States)

    Mao, Xiao-Na; Zhou, Hong-Jing; Yang, Xiao-Jia; Zhao, Li-Xue; Kuang, Xi; Chen, Chu; Liu, Dong-Ling; Du, Jun-Rong

    2017-01-01

    The inhibition of extracellular inflammatory peroxiredoxin (Prx) signaling appears to be a potential therapeutic strategy for neuroinflammatory injury after acute ischemic stroke. Gastrodin (Gas) is a phenolic glycoside that is used for the treatment of cerebral ischemia, accompanied by regulation of the autoimmune inflammatory response. The present study investigated the neuroprotective effects of Gas and its derivative, Gas-D, with a focus on the potential mechanism associated with inflammatory Prx–Toll-like receptor 4 (TLR4) signaling. Gas-D significantly inhibited Prx1-, Prx2-, and Prx4-induced inflammatory responses in RAW264.7 macrophages and H2O2-mediated oxidative injury in SH-SY5Y nerve cells. In rats, intraperitoneal Gas-D administration 10 h after reperfusion following 2-h middle cerebral artery occlusion (MCAO) ameliorated neurological deficits, brain infarction, and neuropathological alterations, including neuron loss, astrocyte and microglia/macrophage activation, T-lymphocyte invasion, and lipid peroxidation. Delayed Gas-D treatment significantly inhibited postischemic Prx1/2/4 expression and spillage, TLR4 signaling activation, and inflammatory mediator production. In contrast, Gas had no significant effects in either cell model or in MCAO rats under the same conditions. These results indicate that Gas-D may be a drug candidate with an extended therapeutic time window that blocks inflammatory responses and attenuates the expression and secretome of inflammatory Prxs in acute ischemic stroke. PMID:29207618

  19. Increasing extracellular H2O2 produces a bi-phasic response in intracellular H2O2, with peroxiredoxin hyperoxidation only triggered once the cellular H2O2-buffering capacity is overwhelmed.

    Science.gov (United States)

    Tomalin, Lewis Elwood; Day, Alison Michelle; Underwood, Zoe Elizabeth; Smith, Graham Robert; Dalle Pezze, Piero; Rallis, Charalampos; Patel, Waseema; Dickinson, Bryan Craig; Bähler, Jürg; Brewer, Thomas Francis; Chang, Christopher Joh-Leung; Shanley, Daryl Pierson; Veal, Elizabeth Ann

    2016-06-01

    Reactive oxygen species, such as H2O2, can damage cells but also promote fundamental processes, including growth, differentiation and migration. The mechanisms allowing cells to differentially respond to toxic or signaling H2O2 levels are poorly defined. Here we reveal that increasing external H2O2 produces a bi-phasic response in intracellular H2O2. Peroxiredoxins (Prx) are abundant peroxidases which protect against genome instability, ageing and cancer. We have developed a dynamic model simulating in vivo changes in Prx oxidation. Remarkably, we show that the thioredoxin peroxidase activity of Prx does not provide any significant protection against external rises in H2O2. Instead, our model and experimental data are consistent with low levels of extracellular H2O2 being efficiently buffered by other thioredoxin-dependent activities, including H2O2-reactive cysteines in the thiol-proteome. We show that when extracellular H2O2 levels overwhelm this buffering capacity, the consequent rise in intracellular H2O2 triggers hyperoxidation of Prx to thioredoxin-resistant, peroxidase-inactive form/s. Accordingly, Prx hyperoxidation signals that H2O2 defenses are breached, diverting thioredoxin to repair damage. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  20. Identification and functional analysis of peroxiredoxin isoforms in Euglena gracilis.

    Science.gov (United States)

    Tamaki, Shun; Maruta, Takanori; Sawa, Yoshihiro; Shigeoka, Shigeru; Ishikawa, Takahiro

    2014-01-01

    Euglena gracilis lacks catalase and contains ascorbate peroxidase (APX) which is localized exclusively in the cytosol. Other enzymes that scavenge reactive oxygen species (ROS) in Euglena have not yet been identified; therefore, ROS metabolism, especially in organelles, remains unclear in Euglena. The full-length cDNAs of four Euglena peroxiredoxins (EgPrxs) were isolated in this study. EgPrx1 and -4 were predicted to be localized in the cytosol, and EgPrx2 and -3 in plastids and mitochondria, respectively. The catalytic efficiencies of recombinant EgPrxs were similar to those of plant thiol-peroxidases, but were markedly lower than those of APX from Euglena. However, transcript levels of EgPrx1, -2, and -3 were markedly higher than those of APX. The growth rate of Euglena cells, in which the expression of EgPrx1 and -4 was suppressed by gene silencing, was markedly reduced under normal conditions, indicating physiological significance of Prx proteins.

  1. "Solid Red Line": An Observational Study on Death from Refractory Intracranial Hypertension.

    Science.gov (United States)

    Czosnyka, M; Aries, M; Weersink, C; Wolf, S; Budohoski, K; Dias, C; Lewis, P; Smielewski, P; Kordasti, S

    2016-01-01

    The index of cerebrovascular pressure reactivity (PRx) correlates independently with outcome after traumatic brain injury (TBI). However, as an index plotted in the time domain, PRx is rather noisy. To "organise" PRx and make its interpretation easier, the colour coding of values, with green when PRx 0.3, has been introduced as a horizontal colour bar on the ICM+ screen. In rare cases of death from refractory intracranial hypertension, an increase in intracranial pressure (ICP) is commonly preceded by values of PRx >0.3, showing a "solid red line".Twenty patients after TBI and one after traumatic subarachnoid haemorrhage (SAH) from six centres in Europe and Australia have been studied. All of them died in a scenario of refractory intracranial hypertension. In the majority of cases the initial ICP was below 20 mmHg and finally increased to values well above 60 mmHg, resulting in cerebral perfusion pressure less than 20 mmHg. In three cases initial ICP was elevated at the start of monitoring. A solid red line was observed in all cases preceding an increase in ICP above 25 mmHg by minutes to hours and in two cases by 2 and 3 days, respectively. If a solid red line is observed over a prolonged period, it should be considered as an indicator of deep cerebrovascular deterioration.

  2. Toxoplasma gondii peroxiredoxin promotes altered macrophage function, caspase-1-dependent IL-1β secretion enhances parasite replication

    Directory of Open Access Journals (Sweden)

    Marshall Edward S

    2011-06-01

    Full Text Available Abstract Alternatively activated macrophages (AAM are a key feature Th2 immunity and have been associated with a variety of roles during helminth infection. The role this cell subset plays in protzoan infection remain relatively unexplored, herein we describe the effects of a redox enzyme (rTgPrx derived from Toxoplasma gondii on murine macrophage phenotype in vitro. RTgPrx has been previously associated with the maintainence of parasite oxidative balance. Here our experiments show that rTgPrx promotes AAM as indicated by high arginase-1 (arg-1, YM1 and FIZZ expression via both signal transducer and activator of transcription (STAT6-dependent and -independent mechanisms. Additionally rTgPrx treatment reduced caspase-1 activity and IL-1β secretion, while simultaneously increasing IL-10 release. Furthermore the in vitro replication of T. gondii (RH strain was enhanced when macrophages were treated with rTgPrx. This is in contrast with the previously described effects of a Plasmodium berghei ANKA 2-cys-peroxiredoxin that promotes pro-inflammatory cytokine production. These results highlight the role of T. gondii derived redox enzymes as important immune modulators and potentially indicate a role for AAM in modulating immunopathology and promoting parasite replication during T. gondii infection.

  3. a Step Toward Development of Printable Dosage Forms for Poorly Soluble Drugs

    DEFF Research Database (Denmark)

    Raijada, Dhara; Genina, Natalja; Fors, Daniela

    2013-01-01

    The purpose of this study was to formulate printable dosage forms for a poorly soluble drug (piroxicam; PRX) and to gain understanding of critical parameters to be considered during development of such dosage forms. Liquid formulations of PRX were printed on edible paper using piezoelectric inkjet...... printing (PIJ) and impression printing (flexography). The printed dosage forms were characterized using scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX) and the amount of drug was determined using high-performance liquid chromatography. Solutions of PRX in polyethylene...... glycol 400 (PEG-400):ethanol (40:60) and in PEG-400 were found to be optimal formulations for PIJ and flexography, respectively. SEM-EDX analysis revealed no visible solid particles on the printed dosage forms indicating the drug most likely remained in solution after printing. More accurate drug...

  4. Identification of differentially expressed proteins during human urinary bladder cancer progression

    DEFF Research Database (Denmark)

    Memon, Ashfaque Ahmed; chang, Jong. w; Oh, Bong R.

    2005-01-01

    Comparative proteome analysis was performed between RT4 (grade-1) and T24 (grade-3) bladder cancer cell lines, in an attempt to identify differentially expressed proteins during bladder cancer progression. Among those relatively abundant proteins, seven spots changed more than two-fold reproducibly...... and identified by peptide mass fingerprinting using mass spectrometry and database search. We found most extensive and reproducible down-regulation of NADP dependent isocitrate dehydrogenase cytoplasmic (IDPc) and peroxiredoxin-II (Prx-II), in poorly differentiated T24 compared to well-differentiated RT4 bladder...... cancer cell line. Subsequent Western blotting analysis of human biopsy samples from bladder cancer patient revealed significant loss of IDPc and Prx-II in more advance tumor samples, in agreement with data on cell lines. These results suggest that loss of IDPc and Prx-II during tumor development may...

  5. Cell signaling promoting protein carbonylation does not cause sulfhydryl oxidation: Implications to the mechanism of redox signaling [version 1; referees: 1 approved, 2 approved with reservations

    Directory of Open Access Journals (Sweden)

    Yuichiro J. Suzuki

    2017-04-01

    Full Text Available Reactive oxygen species (ROS have been recognized as second messengers, however, targeting mechanisms for ROS in cell signaling have not been defined. While ROS oxidizing protein cysteine thiols has been the most popular proposed mechanism, our laboratory proposed that ligand/receptor-mediated cell signaling involves protein carbonylation. Peroxiredoxin-6 (Prx6 is one protein that is carbonylated at 10 min after the platelet-derived growth factor (PDGF stimulation of human pulmonary artery smooth muscle cells. In the present study, the SulfoBiotics Protein Redox State Monitoring Kit Plus (Dojindo Molecular Technologies was used to test if cysteine residues of Prx6 are oxidized in response to the PDGF stimulation. Human Prx6 has a molecular weight of 25 kDa and contains two cysteine residues. The Dojindo system adds the 15 kDa Protein-SHifter if these cysteine residues are reduced in the cells. Results showed that, in untreated cells, the Prx6 molecule predominantly exhibited the 55 kDa band, indicating that both cysteine residues are reduced in the cells. Treatment of cells with 1 mM H2O2 caused the disappearance of the 55 kDa band and the appearance of a 40 kDa band, suggesting that the high concentration of H2O2 oxidized one of the two cysteine residues in the Prx6 molecule. By contrast, PDGF stimulation had no effects on the thiol status of the Prx6 molecule. We concluded that protein carbonylation is a more sensitive target of ROS during ligand/receptor-mediated cell signaling than sulfhydryl oxidation.

  6. Cell signaling promoting protein carbonylation does not cause sulfhydryl oxidation: Implications to the mechanism of redox signaling.

    Science.gov (United States)

    Suzuki, Yuichiro J; Almansour, Faisal; Cucinotta, Camilla; Rybka, Vladyslava; Marcocci, Lucia

    2017-01-01

    Reactive oxygen species (ROS) have been recognized as second messengers, however, targeting mechanisms for ROS in cell signaling have not been defined. While ROS oxidizing protein cysteine thiols has been the most popular proposed mechanism, our laboratory proposed that ligand/receptor-mediated cell signaling involves protein carbonylation. Peroxiredoxin-6 (Prx6) is one protein that is carbonylated at 10 min after the platelet-derived growth factor (PDGF) stimulation of human pulmonary artery smooth muscle cells. In the present study, the SulfoBiotics Protein Redox State Monitoring Kit Plus (Dojindo Molecular Technologies) was used to test if cysteine residues of Prx6 are oxidized in response to the PDGF stimulation. Human Prx6 has a molecular weight of 25 kDa and contains two cysteine residues. The Dojindo system adds the 15 kDa Protein-SHifter if these cysteine residues are reduced in the cells. Results showed that, in untreated cells, the Prx6 molecule predominantly exhibited the 55 kDa band, indicating that both cysteine residues are reduced in the cells. Treatment of cells with 1 mM H 2O 2 caused the disappearance of the 55 kDa band and the appearance of a 40 kDa band, suggesting that the high concentration of H 2O 2 oxidized one of the two cysteine residues in the Prx6 molecule. By contrast, PDGF stimulation had no effects on the thiol status of the Prx6 molecule. We concluded that protein carbonylation is a more sensitive target of ROS during ligand/receptor-mediated cell signaling than sulfhydryl oxidation.

  7. Reference: 712 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available rtas Maria C et al. 2007 Dec. Plant Cell 19(12):4120-30. Nitric oxide (NO) is a free radical product of cell... metabolism that plays diverse and important roles in the regulation of cellular function. S-Nitrosylation i... We investigated the molecular mechanism for S-nitrosylation of peroxiredoxin II E (PrxII E) from Arabidopsi...s thaliana and found that this posttranslational modification inhibits the hydroperoxide-re...ducing peroxidase activity of PrxII E, thus revealing a novel regulatory mechanism for peroxiredoxins. Furthermore

  8. Electronic and Ionic Transport in Ce0.8PrxTb0.2−xO2−δ and Evaluation of Performance as Oxygen Permeation Membranes

    DEFF Research Database (Denmark)

    Chatzichristodoulou, Christodoulos; Hendriksen, Peter Vang

    2012-01-01

    to that of Ce0.9Gd0.1O1.95−δ, and was found to increase with increasing Pr/Tb ratio. The oxide ion mobility in Ce0.8PrxTb0.2−xO2−δ is similar to that in Ce1−2δGd2δO2−δ at the same oxygen vacancy concentration. Based on the measured ionic and electronic conductivities, fluxes through thin film Ce0.8PrxTb0.2−xO2...

  9. SHuffle, a novel Escherichia coli protein expression strain capable of correctly folding disulfide bonded proteins in its cytoplasm

    Directory of Open Access Journals (Sweden)

    Lobstein Julie

    2012-05-01

    Full Text Available Abstract Background Production of correctly disulfide bonded proteins to high yields remains a challenge. Recombinant protein expression in Escherichia coli is the popular choice, especially within the research community. While there is an ever growing demand for new expression strains, few strains are dedicated to post-translational modifications, such as disulfide bond formation. Thus, new protein expression strains must be engineered and the parameters involved in producing disulfide bonded proteins must be understood. Results We have engineered a new E. coli protein expression strain named SHuffle, dedicated to producing correctly disulfide bonded active proteins to high yields within its cytoplasm. This strain is based on the trxB gor suppressor strain SMG96 where its cytoplasmic reductive pathways have been diminished, allowing for the formation of disulfide bonds in the cytoplasm. We have further engineered a major improvement by integrating into its chromosome a signal sequenceless disulfide bond isomerase, DsbC. We probed the redox state of DsbC in the oxidizing cytoplasm and evaluated its role in assisting the formation of correctly folded multi-disulfide bonded proteins. We optimized protein expression conditions, varying temperature, induction conditions, strain background and the co-expression of various helper proteins. We found that temperature has the biggest impact on improving yields and that the E. coli B strain background of this strain was superior to the K12 version. We also discovered that auto-expression of substrate target proteins using this strain resulted in higher yields of active pure protein. Finally, we found that co-expression of mutant thioredoxins and PDI homologs improved yields of various substrate proteins. Conclusions This work is the first extensive characterization of the trxB gor suppressor strain. The results presented should help researchers design the appropriate protein expression conditions using

  10. Flavoprotein-mediated tellurite reduction: structural basis and applications to the synthesis of tellurium-containing nanostructures

    Directory of Open Access Journals (Sweden)

    Mauricio Arenas-Salinas

    2016-07-01

    Full Text Available The tellurium oxyanion tellurite (TeO32- is extremely harmful for most organisms. It has been suggested that a potential bacterial tellurite resistance mechanism would consist of an enzymatic, NAD(PH-dependent, reduction to the less toxic form elemental tellurium (Te0. To date, a number of enzymes such as catalase, type II NADH dehydrogenase and terminal oxidases from the electron transport chain, nitrate reductases, and dihydrolipoamide dehydrogenase (E3, among others, have been shown to display tellurite-reducing activity. This activity is generically referred to as tellurite reductase (TR. Bioinformatic data resting on some of the abovementioned enzymes enabled the identification of common structures involved in tellurite reduction including vicinal catalytic cysteine residues and the FAD/NAD(P+-binding domain, which is characteristic of some flavoproteins. Along this line, thioredoxin reductase (TrxB, alkyl hydroperoxide reductase (AhpF, glutathione reductase (GorA, mercuric reductase (MerA, NADH: flavorubredoxin reductase (NorW, dihydrolipoamide dehydrogenase, and the putative oxidoreductase YkgC from Escherichia coli or environmental bacteria were purified and assessed for TR activity. All of them displayed in vitro TR activity at the expense of NADH or NADPH oxidation. In general, optimal reducing conditions occurred around pH 9-10 and 37 °C.Enzymes exhibiting strong TR activity produced Te-containing nanostructures (TeNS. While GorA and AhpF generated TeNS of 75 nm average diameter, E3 and YkgC produced larger structures (> 100 nm. Electron-dense structures were observed in cells over-expressing genes encoding TrxB, GorA and YkgC.

  11. Barley coleoptile peroxidases. Purification, molecular cloning, and induction by pathogens

    DEFF Research Database (Denmark)

    Kristensen, B.K.; Bloch, H.; Rasmussen, Søren Kjærsgård

    1999-01-01

    -transcriptase polymerase chain reaction showed that the Prx7 protein and mRNA accumulated abundantly in barley coleoptiles and in leaf epidermis inoculated with powdery mildew fungus (Blumeria graminis). Two isoperoxidases with isoelectric points of 9.3 and 7.3 (P9.3 and P7.3, respectively) were purified to homogeneity...... from barley coleoptiles. P9.3 and P7.3 had Reinheitszahl values of 3.31 and 2.85 and specific activities (with 2,2'-azino-di-[3-ethyl-benzothiazoline-6-sulfonic acid], pH 5.5, as the substrate) of 11 and 79 units/mg, respectively. N-terminal amino acid sequencing and matrix-assisted laser desorption....../ionization time-of-flight mass-spectrometry peptide analysis identified the P9.3 peroxidase activity as due to Prx7. Tissue and subcellular accumulation of Prx7 was studied using activity-stained isoelectric focusing gels and immunoblotting. The peroxidase activity due to Prx7 accumulated in barley leaves 24 h...

  12. Percolative transport in the vicinity of charge-order ferromagnetic ...

    Indian Academy of Sciences (India)

    Prx )0.7Ca0.3MnO3 thin films fabricated on (100) oriented SrTiO3 single crystals by pulsed laser de- position. The end ... The electric field driven charge transport in the system is modelled on the basis of an inhomogeneous medium consisting of ferromagnetic metallic clusters dispersed in a CO background. Keywords.

  13. Stable Agrobacterium -mediated transformation of the halophytic ...

    African Journals Online (AJOL)

    In this study, an efficient procedure for stable Agrobacterium-mediated transformation of Leymus chinensis (Trin.) was established. Agrobacterium tumefaciens strain EHA105, harboring a binary vector pCAMBIA2300, was used for transformation, along with a sweet potato 2-cysteine peroxiredoxin (2-Cys Prx) gene under ...

  14. Mitochondrial Respiratory Chain Inhibitors Involved in ROS Production Induced by Acute High Concentrations of Iodide and the Effects of SOD as a Protective Factor

    Directory of Open Access Journals (Sweden)

    Lingyan Wang

    2015-01-01

    Full Text Available A major source of reactive oxygen species (ROS generation is the mitochondria. By using flow cytometry of the mitochondrial fluorescent probe, MitoSOX Red, western blot of mitochondrial ROS scavenger Peroxiredoxin (Prx 3 and fluorescence immunostaining, ELISA of cleaved caspases 3 and 9, and TUNEL staining, we demonstrated that exposure to 100 μM KI for 2 hours significantly increased mitochondrial superoxide production and Prx 3 protein expression with increased expressions of cleaved caspases 3 and 9. Besides, we indicated that superoxide dismutase (SOD at 1000 unit/mL attenuated the increase in mitochondrial superoxide production, Prx 3 protein expression, and lactate dehydrogenase (LDH release and improved the relative cell viability at 100 μM KI exposure. However, SOD inhibitor diethyldithiocarbamic acid (DETC (2 mM, Rotenone (0.5 μM, a mitochondrial complex I inhibitor, and Antimycin A (10 μM, a complex III inhibitor, caused an increase in mitochondrial superoxide production, Prx 3 protein expression, and LDH release and decreased the relative cell viability. We conclude that the inhibitors of mitochondrial respiratory chain complex I or III may be involved in oxidative stress caused by elevated concentrations of iodide, and SOD demonstrates its protective effect on the Fischer rat thyroid cell line (FRTL cells.

  15. Cysteine specific targeting of the functionally distinct peroxiredoxin and glutaredoxin proteins by the investigational disulfide BNP7787.

    Science.gov (United States)

    Parker, Aulma R; Petluru, Pavankumar N; Nienaber, Vicki L; Badger, John; Leverett, Betsy D; Jair, Kamwing; Sridhar, Vandana; Logan, Cheyenne; Ayala, Philippe Y; Kochat, Harry; Hausheer, Frederick H

    2015-03-18

    Glutaredoxin (Grx), peroxiredoxin (Prx), and thioredoxin (Trx) are redoxin family proteins that catalyze different types of chemical reactions that impact cell growth and survival through functionally distinct intracellular pathways. Much research is focused on understanding the roles of these redoxin proteins in the development and/or progression of human diseases. Grx and Prx are overexpressed in human cancers, including human lung cancers. BNP7787 is a novel investigational agent that has been evaluated in previous clinical studies, including non-small cell lung cancer (NSCLC) studies. Herein, data from activity assays, mass spectrometry analyses, and X-ray crystallographic studies indicate that BNP7787 forms mixed disulfides with select cysteine residues on Grx and Prx and modulates their function. Studies of interactions between BNP7787 and Trx have been conducted and reported separately. Despite the fact that Trx, Grx, and Prx are functionally distinct proteins that impact oxidative stress, cell proliferation and disease processes through different intracellular pathways, BNP7787 can modify each protein and appears to modulate function through mechanisms that are unique to each target protein. Tumor cells are often genomically heterogeneous containing subpopulations of cancer cells that often express different tumor-promoting proteins or that have multiple dysregulated signaling pathways modulating cell proliferation and drug resistance. A multi-targeted agent that simultaneously modulates activity of proteins important in mediating cell proliferation by functionally distinct intracellular pathways could have many potentially useful therapeutic applications.

  16. Cysteine Specific Targeting of the Functionally Distinct Peroxiredoxin and Glutaredoxin Proteins by the Investigational Disulfide BNP7787

    Directory of Open Access Journals (Sweden)

    Aulma R. Parker

    2015-03-01

    Full Text Available Glutaredoxin (Grx, peroxiredoxin (Prx, and thioredoxin (Trx are redoxin family proteins that catalyze different types of chemical reactions that impact cell growth and survival through functionally distinct intracellular pathways. Much research is focused on understanding the roles of these redoxin proteins in the development and/or progression of human diseases. Grx and Prx are overexpressed in human cancers, including human lung cancers. BNP7787 is a novel investigational agent that has been evaluated in previous clinical studies, including non-small cell lung cancer (NSCLC studies. Herein, data from activity assays, mass spectrometry analyses, and X-ray crystallographic studies indicate that BNP7787 forms mixed disulfides with select cysteine residues on Grx and Prx and modulates their function. Studies of interactions between BNP7787 and Trx have been conducted and reported separately. Despite the fact that Trx, Grx, and Prx are functionally distinct proteins that impact oxidative stress, cell proliferation and disease processes through different intracellular pathways, BNP7787 can modify each protein and appears to modulate function through mechanisms that are unique to each target protein. Tumor cells are often genomically heterogeneous containing subpopulations of cancer cells that often express different tumor-promoting proteins or that have multiple dysregulated signaling pathways modulating cell proliferation and drug resistance. A multi-targeted agent that simultaneously modulates activity of proteins important in mediating cell proliferation by functionally distinct intracellular pathways could have many potentially useful therapeutic applications.

  17. Effects of Benzalkonium Chloride, Proxel LV, P3 Hypochloran, Triton X-100 and DOWFAX 63N10 on anaerobic digestion processes

    DEFF Research Database (Denmark)

    Flores, German Antonio Enriquez; Fotidis, Ioannis; Karakashev, Dimitar Borisov

    2015-01-01

    In this study, the individual and synergistic toxicity of the following xenobiotics: Benzalkonium Chloride (BKC), Proxel LV (PRX), P3 Hypochloran (HPC), Triton X-100 (TRX), and DOWFAX 63N10 (DWF), on anaerobic digestion (AD) process, was assessed. The experiments were performed in batch and conti...

  18. Oxidative Stress Promotes Peroxiredoxin Hyperoxidation and Attenuates Pro-survival Signaling in Aging Chondrocytes.

    Science.gov (United States)

    Collins, John A; Wood, Scott T; Nelson, Kimberly J; Rowe, Meredith A; Carlson, Cathy S; Chubinskaya, Susan; Poole, Leslie B; Furdui, Cristina M; Loeser, Richard F

    2016-03-25

    Oxidative stress-mediated post-translational modifications of redox-sensitive proteins are postulated as a key mechanism underlying age-related cellular dysfunction and disease progression. Peroxiredoxins (PRX) are critical intracellular antioxidants that also regulate redox signaling events. Age-related osteoarthritis is a common form of arthritis that has been associated with mitochondrial dysfunction and oxidative stress. The objective of this study was to determine the effect of aging and oxidative stress on chondrocyte intracellular signaling, with a specific focus on oxidation of cytosolic PRX2 and mitochondrial PRX3. Menadione was used as a model to induce cellular oxidative stress. Compared with chondrocytes isolated from young adult humans, chondrocytes from older adults exhibited higher levels of PRX1-3 hyperoxidation basally and under conditions of oxidative stress. Peroxiredoxin hyperoxidation was associated with inhibition of pro-survival Akt signaling and stimulation of pro-death p38 signaling. These changes were prevented in cultured human chondrocytes by adenoviral expression of catalase targeted to the mitochondria (MCAT) and in cartilage explants from MCAT transgenic mice. Peroxiredoxin hyperoxidation was observedin situin human cartilage sections from older adults and in osteoarthritic cartilage. MCAT transgenic mice exhibited less age-related osteoarthritis. These findings demonstrate that age-related oxidative stress can disrupt normal physiological signaling and contribute to osteoarthritis and suggest peroxiredoxin hyperoxidation as a potential mechanism. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  19. Crystal structure of peroxiredoxin from Aeropyrum pernix K1 complexed with its substrate, hydrogen peroxide.

    Science.gov (United States)

    Nakamura, Tsutomu; Kado, Yuji; Yamaguchi, Takafumi; Matsumura, Hiroyoshi; Ishikawa, Kazuhiko; Inoue, Tsuyoshi

    2010-01-01

    Peroxiredoxin (Prx) reduces hydrogen peroxide and alkyl peroxides to water and corresponding alcohols, respectively. The reaction is dependent on a peroxidatic cysteine, whose sulphur atom nucleophilically attacks one of the oxygen atoms of the peroxide substrate. In spite of the many structural studies that have been carried out on this reaction, the tertiary structure of the hydrogen peroxide-bound form of Prx has not been elucidated. In this paper, we report the crystal structure of Prx from Aeropyrum pernix K1 in the peroxide-bound form. The conformation of the polypeptide chain is the same as that in the reduced apo-form. The hydrogen peroxide molecule is in close contact with the peroxidatic Cys50 and the neighbouring Thr47 and Arg126 side chain atoms, as well as with the main chain nitrogen atoms of Val49 and Cys50. Bound peroxide was also observed in the mutant C50S, in which the peroxidatic cysteine was replaced by serine. Therefore, the sulphur atom of the peroxidatic cysteine is not essential for peroxide binding, although it enhances the binding affinity. Hydrogen peroxide binds to the protein so that it fills the active site pocket. This study provides insight into the early stage of the Prx reaction.

  20. Quinone- and nitroreductase reactions of Thermotoga maritima peroxiredoxin-nitroreductase hybrid enzyme.

    Science.gov (United States)

    Anusevičius, Žilvinas; Misevičienė, Lina; Šarlauskas, Jonas; Rouhier, Nicolas; Jacquot, Jean-Pierre; Čėnas, Narimantas

    2012-12-01

    Thermotoga maritima peroxiredoxin-nitroreductase hybrid enzyme (Prx-NR) consists of a FMN-containing nitroreductase (NR) domain fused to a peroxiredoxin (Prx) domain. These domains seem to function independently as no electron transfer occurs between them. The reduction of quinones and nitroaromatics by NR proceeded in a two-electron manner, and follows a 'ping-pong' scheme with sometimes pronounced inhibition by quinone substrate. The comparison of steady- and presteady-state kinetic data shows that in most cases, the oxidative half-reaction may be rate-limiting in the catalytic cycle of NR. The enzyme was inhibited by dicumarol, a classical inhibitor of oxygen-insensitive nitroreductases. The reduction of quinones and nitroaromatic compounds by Prx-NR was characterized by the linear dependence of their reactivity (logk(cat)/K(m)) on their single-electron reduction potentials E(7)(1), while the reactivity of quinones markedly exceeded the one with nitroaromatics. It shows that NR lacks the specificity for the particular structure of these oxidants, except their single-electron accepting potency and the rate of electron self-exchange. It points to the possibility of a single-electron transfer step in a net two-electron reduction of quinones and nitroaromatics by T. maritima Prx-NR, and to a significant diversity of the structures of flavoenzymes which may perform the two-electron reduction of quinones and nitroaromatics. Copyright © 2012 Elsevier Inc. All rights reserved.

  1. The effects of Peroxiredoxin VI on the preservation of the small intestine in rats after ischemia/reperfusion damage

    Directory of Open Access Journals (Sweden)

    A. E. Gordeeva

    2014-01-01

    Full Text Available The intestine is an extremely sensitive organ with regard to ischemia/reperfusion damage (I/R because of its high oxygen reguirement. The aim of this study is to investigate the effects of Peroxiredoxin VI (Prx VI on preservation of the small intestine after the intestinal ischemia/reperfusion injury in strangulation ileum model. Intestinal ischemia/ reperfusion injury in strangulation model was produced by occlusion of the distal ileum loop and mesentery with its blood vessels for 60 min followed by a 120-min reperfusion period. A group of animals received intravenous injections of 10 mg/kg Prx VI 15 min prior to the intestinal ischemia/reperfusion in the strangulation model. After surgery, part of the intestine was collected for histological analysis. In I/R group a breakdown in the integrity of villi and crypts was revealed, as well as infiltration of lymphocytes, oxidative damage with serious mucosal loss. Prx VI pretreatment to rats with ischemia/reperfusion injury protected the intestine from ischemia/reperfusion injury by reducing oxidative damage and preserving intestinal mucosal composition. These results demonstrated that Prx VI possessed advantageous antioxidant effects as well as effectively attenuated ischemia-reperfusion trauma of the strangulated intestine segment. 

  2. Preparation and characterization of N-benzyl-N,O-succinyl chitosan ...

    African Journals Online (AJOL)

    Purpose: To investigate the solubilization of poorly water-soluble non-steroidal anti-inflammatory drugs (NSAIDs) in N-benzyl-N,O-succinyl chitosan (BSCS) polymeric micelles. Methods: BSCS was synthesized by reductive amination and succinylation, respectively. NSAIDs; meloxicam (MX), piroxicam (PRX), ketoprofen ...

  3. Supramolecular self-assembly of graphene oxide and metal nanoparticles into stacked multilayers by means of a multitasking protein ring.

    Science.gov (United States)

    Ardini, Matteo; Golia, Giordana; Passaretti, Paolo; Cimini, Annamaria; Pitari, Giuseppina; Giansanti, Francesco; Di Leandro, Luana; Ottaviano, Luca; Perrozzi, Francesco; Santucci, Sandro; Morandi, Vittorio; Ortolani, Luca; Christian, Meganne; Treossi, Emanuele; Palermo, Vincenzo; Angelucci, Francesco; Ippoliti, Rodolfo

    2016-03-28

    Graphene oxide (GO) is rapidly emerging worldwide as a breakthrough precursor material for next-generation devices. However, this requires the transition of its two-dimensional layered structure into more accessible three-dimensional (3D) arrays. Peroxiredoxins (Prx) are a family of multitasking redox enzymes, self-assembling into ring-like architectures. Taking advantage of both their symmetric structure and function, 3D reduced GO-based composites are hereby built up. Results reveal that the "double-faced" Prx rings can adhere flat on single GO layers and partially reduce them by their sulfur-containing amino acids, driving their stacking into 3D multi-layer reduced GO-Prx composites. This process occurs in aqueous solution at a very low GO concentration, i.e. 0.2 mg ml(-1). Further, protein engineering allows the Prx ring to be enriched with metal binding sites inside its lumen. This feature is exploited to both capture presynthesized gold nanoparticles and grow in situ palladium nanoparticles paving the way to straightforward and "green" routes to 3D reduced GO-metal composite materials.

  4. Protein Crowding in Lipid Bilayers Gives Rise to Non-Gaussian Anomalous Lateral Diffusion of Phospholipids and Proteins

    Czech Academy of Sciences Publication Activity Database

    Jeon, J. H.; Javanainen, M.; Martinez-Seara, Hector; Metzler, R.; Vattulainen, I.

    2016-01-01

    Roč. 6, č. 2 (2016), č. článku 021006. ISSN 2160-3308 Institutional support: RVO:61388963 Keywords : protein crowding * membranes * simulations * diffusion * non-Gaussian anomalous diffusion Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 12.789, year: 2016 http://journals.aps.org/prx/abstract/10.1103/PhysRevX.6.021006

  5. The influence of piroxicam, a non-selective cyclooxygenase inhibitor, on autonomic nervous system activity in experimental cyclophosphamide-induced hemorrhagic cystitis and bladder outlet obstruction in rats.

    Science.gov (United States)

    Dobrek, Łukasz; Baranowska, Agnieszka; Skowron, Beata; Thor, Piotr J

    2014-01-01

    Signs and symptoms of secondary overactive bladder (OAB) are observed both in course of infravesical obstruction of urine outflow in patients with benign prostatic hyperplasia, and as a result of development of hemorrhagic cystitis (HC) following administration of cyclophosphamide (CP). Non-steroidal antiinflammatory drugs (NSAIDs) alleviate symptoms of bladder overactivity reducing local synthesis of prostaglandins (PGs), but precise effects of those agents on functions of the autonomic nervous system (ANS) in course of OAB remain unknown. The purpose of this study was to evaluate the effect of piroxicam-induced prostaglandins (PGs) synthesis block on activity of the ANS in two experimental models of secondary OAB: bladder outlet obstruction (BOO) and cyclophosphamide-induced HC (CP-HC), by heart rate variability analysis (HRV). The experiment was performed on a group of rats with surgically induced 2-week BOO, and on a group of rats that were administered CP five times, with corresponding control groups. Study animals were given piroxicam (PRX) i.p. in two doses: 2 and 10 mg/kg b.w. In the BOO model, PRX in both doses revealed a trend for reduction of value of all non-normalized components of HRV. The lower PRX dose caused an increased nHF value, and PRX administered in the dose of 10 mg/kg b.w. caused an increase of the nLF value. In the CP-HC model, the lower PRX dose caused a trend for an increase of values of all non-normalized components, and the higher dose--for their decrease. Both doses of PRX in that model caused increase of the nLF value. Inhibition of PGs synthesis caused changes of ANS function in both models of OAB. Both in BOO and in CP-HC, PGs seem to be ANS-activating factors, responsible for maintenance of a high parasympathetic activity. In both models, inhibition of PGs synthesis with PRX administered at the dose of 10 mg/kg b.w. lead to functional reconstruction of ANS, with marked sympathetic predominance. That may contribute to reduction of

  6. Enhanced radiation response in radioresistant MCF-7 cells by targeting peroxiredoxin II

    Directory of Open Access Journals (Sweden)

    Diaz AJG

    2013-10-01

    Full Text Available Anthony Joseph Gomez Diaz,1 Daniel Tamae,2 Yun Yen,3 JianJian Li,4 Tieli Wang1 1Department of Chemistry and Biochemistry, California State University at Dominguez Hills, Carson, CA, 2Center of Excellence in Environmental Toxicology, Department of Pharmacology, University of Pennsylvania, Philadelphia, PA, 3Department of Clinical and Molecular Pharmacology, Beckman Research Institute of City of Hope National Medical Center, Duarte, CA, 4Department of Radiation Oncology, University of California Davis, Sacramento, CA, USA Abstract: In our previous study, we identified that a protein target, peroxiredoxin II (PrxII, is overexpressed in radioresistant MCF+FIR3 breast-cancer cells and found that its expression and function is associated with breast-cancer radiation sensitivity or resistance. Small interference RNA (siRNA targeting PrxII gene expression was able to sensitize MCF+FIR3 radioresistant breast-cancer cells to ionizing radiation. The major focus of this work was to investigate how the radiation response of MCF+FIR3 radioresistant cells was affected by the siRNA that inhibits PrxII gene expression. Our results, presented here, show that silencing PrxII gene expression increased cellular toxicity by altering cellular thiol status, inhibiting Ca2+ efflux from the cells, and perturbing the intracellular Ca2+ homeostasis. By combining radiotherapy and siRNA technology, we hope to develop new therapeutic strategies that may have potential to enhance the efficacy of chemotherapeutic agents due to this technology's property of targeting to specific cancer-related genes. Keywords: siRNA, PrxII, radiation resistance, Ca2+, MCF+FIR3

  7. Effect of Intra-Arterial and Intravenous Nimodipine Therapy of Cerebral Vasospasm After Subarachnoid Hemorrhage on Cerebrovascular Reactivity and Oxygenation.

    Science.gov (United States)

    Hockel, Konstantin; Diedler, Jennifer; Steiner, Jochen; Birkenhauer, Ulrich; Ernemann, Ulrike; Schuhmann, Martin U

    2017-05-01

    For the treatment and prevention of delayed cerebral ischemia after subarachnoid hemorrhage, the vasodilating agent nimodipine (NDP) is widely employed. This study investigates the effect of NDP on cerebrovascular autoregulation, assessed by pressure reactivity index (PRx), and brain tissue oxygenation (pbrO2) when given continuously intravenously as an intra-arterial bolus or during continuous intra-arterial therapy. Computerized continuous neuromonitoring data (intracranial pressure, mean arterial pressure, cerebral perfusion pressure [CPP], pbrO2, PRx) of 105 patients with aneurysmal SAH were retrospectively evaluated. The effect of NDP on all parameters was compared when applied intra-arterially for the treatment of severe macrovasospasm leading to perfusion deficits as either bolus treatment (n = 111 in 37 patients) or continuous infusion (n = 20 patients) to patients without or with only mild macrovasospasm who received either intravenous NDP or no NDP at all. Compared with patients without treatment, the intravenous application of NDP was associated with a significantly higher PRx. Autoregulation was strongly and long lastingly affected (high PRx) in continuous intra-arterial NDP infusion, accompanied by a sustained improvement of pbrO2. Intra-arterial bolus NDP application resulted as well in a significant increase of pbrO2 and PRx; the induced effect, however, was transient and subsided within 6 hours. Intracranial pressure, mean arterial pressure, and CPP were not affected during the monitoring period. The pharmacologically induced alteration of the cerebrovascular autoregulation by NDP correlates with changes of pbrO2 and indicates a beneficial effect on cerebral blood flow if CPP is maintained. This effect is limited to a few hours after bolus treatment and milder for intravenous compared with intra-arterial application. Copyright © 2017. Published by Elsevier Inc.

  8. Spectral heart rate variability in rats with cyclophosphamide-induced hemorrhagic cystitis treated with cyclooxygenase inhibitors.

    Science.gov (United States)

    Dobrek, Łukasz; Baranowska, Agnieszka; Ciesielczyk, Katarzyna; Thor, Piotr J

    2015-01-01

    The pathogenesis of cyclophosphamide-induced hemorrhagic cystitis (CP-HC) is complex, involving the im- pact of many systemically and locally released agents on autonomic nervous system (ANS) activity, that affects bladder functioning. The purpose of our study was to provide an indirect evaluation of ANS functional status in experimental CP-HC model, involving prostaglandin synthesis block resulting from administration of cyclooxygenase inhibitors. The ANS activity was estimated through the spectral analysis of heart rate variability (HRV) in CP-HC rats divided into three study groups: 1-control, 2-treated with meloxicam (MLX) that preferentially blocks COX-2, and 3-treated with piroxicam (PRX) that inhibits COX1 and 2 activity. In animals treated either with MLX or PRX, the percent distribution of the spectrum in relation to components of very low (VLF) and low (LF) frequency was not different from the control group. PRX-treated group displayed nearly two times lower percent share of the high frequency (HF) component compared to the control. Moreover, an increase of the normalized LF (nLF) value with simultaneous reduction of the normalized HF (nHF) value were noted in PRX-treated rat with no change of these parameters for MLX-treated rats. The HRV analysis in CP-HC rats receiving PRX, indicated a functional reorganization manifested by reduced parasym- pathetic activity and increased sympathetic tonus. A partial prostaglandin synthesis block caused by COX-2 inhibitor (meloxicam) caused no significant changes of evaluated HRV parameters compared to the control. Assessing functional changes of the ANS caused by prostaglandin synthesis block it should be stated that prostaglandins synthesized by the constitutive COX-1 isoform seem to maintain the parasympathetic activity, which may be associated with the cholinergic anti-inflammatory pathway and resolution of inflammation in course of cyclophosphamide-induced cystitis.

  9. Expression of immune-related genes in larval stages of the giant tiger shrimp, Penaeus monodon.

    Science.gov (United States)

    Jiravanichpaisal, Pikul; Puanglarp, Narongsak; Petkon, Sasithon; Donnuea, Seri; Söderhäll, Irene; Söderhäll, Kenneth

    2007-10-01

    Shrimp undergo several morphologically different stages during development and therefore the expression of some immune-related genes such as prophenoloxidase (proPO), peroxinectin (Prx), crustin (Crus), penaeidin (Pen), transglutaminase (TGase), haemocyanin (Hc) and astakine (Ak) were determined during larval development of the shrimp (Penaeus monodon), i.e. nauplius 4 (N4), protozoea 1 and 3 (Z1 and 3), mysis 3 (My 3), post-larvae 3 (PL3) and also in haemocytes of juveniles. Semi-quantitative RT-PCR analysis showed that all transcripts were already present in the early larval stage of N4 but at different levels. The transcript of proPO was found to be extremely low or even absent at N4, whereas Prx, Crus, Pen, TGase, Hc and Ak were significantly expressed at all larval stages. Up to now expression of proPO and Prx has only been reported from haemocytes in crustaceans and in this study Prx also appeared to be expressed in stages which appear to lack haemocytes. Thus, this may suggest that Prx is expressed in other cells than haemocytes. It is well known among invertebrates that the proPO system plays a crucial role as an immune effector molecule against microbes. However, in this study, the transcript of proPO was low during the larval stages and hardly present at all at N4. This might indicate that the development of immune-competent haemocytes during the larval stages is not completed and as a consequence they are likely to be more susceptible to infectious diseases during these stages.

  10. Pressure Autoregulation Measurement Techniques in Adult Traumatic Brain Injury, Part II: A Scoping Review of Continuous Methods.

    Science.gov (United States)

    Zeiler, Frederick A; Donnelly, Joseph; Calviello, Leanne; Smielewski, Peter; Menon, David K; Czosnyka, Marek

    2017-12-01

    A scoping review of the literature was performed systematically on commonly described continuous autoregulation measurement techniques in adult traumatic brain injury (TBI) to provide an overview of methodology and comprehensive reference library of the available literature for each technique. Five separate small systematic reviews were conducted for each of the continuous techniques: pressure reactivity index (PRx), laser Doppler flowmetry (LDF), near infrared spectroscopy (NIRS) techniques, brain tissue oxygen tension (PbtO 2 ), and thermal diffusion (TD) techniques. Articles from MEDLINE, BIOSIS, EMBASE, Global Health, Scopus, Cochrane Library (inception to December 2016), and reference lists of relevant articles were searched. A two-tier filter of references was conducted. The literature base identified from the individual searches was limited, except for PRx. The total number of articles using each of the five searched techniques for continuous autoregulation in adult TBI were: PRx (28), LDF (4), NIRS (9), PbtO 2 (10), and TD (8). All continuous techniques described in adult TBI are based on moving correlation coefficients. The premise behind the calculation of these moving correlation coefficients focuses on the impact of slow fluctuations in either mean arterial pressure (MAP) or cerebral perfusion pressure (CPP) on some indirect measure of cerebral blood flow (CBF), such as: intracranial pressure (ICP), LDF, NIRS signals, PbtO 2 , or TD CBF. The thought is the correlation between a hemodynamic driving factor, such as MAP or CPP, and a surrogate for CBF or cerebral perfusion sheds insight on the state of cerebral autoregulation. Both PRx and NIRS indices were validated experimentally against the "gold standard" static autoregulatory curve (Lassen curve) at least around the lower threshold of autoregulation. The PRx has the largest literature base supporting the association with patient outcome. Various methods of continuous autoregulation assessment are

  11. Oxidative stress and protein oxidation in the brain of water drinking and alcohol drinking rats administered the HIV envelope protein, gp120.

    Science.gov (United States)

    Singh, Ashok K; Gupta, Shveta; Jiang, Yin

    2008-03-01

    Possible roles of oxidative stress and protein oxidation on alcohol-induced augmentation of cerebral neuropathy in gp120 administered alcohol preferring rats drinking either pure water (W rats) or a free-choice ethanol and water (E rats) for 90 days. This study showed that peripherally administered gp120 accumulated into the brain, liver, and RBCs samples from water drinking - gp120 administered rats (Wg rats) and ethanol drinking - gp120 administered rats (Eg rats), although gp120 levels in samples from Eg rats were significantly greater than the levels in samples from Wg rats. The brain samples from ethanol drinking-saline administered (EC) and Wg rats exhibited comparable levels of free radicals that were significantly lower than the levels in Eg rats. Peroxiredoxin-I (PrxI) activity in the brain samples exhibited the following pattern: Wg > > WC > EC > Eg. Total protein-carbonyl and carbonylated hippocampal cholinergic neurostimulating peptide precursor protein levels, but not N-acetylaspartate or N-acetyl aspartylglutamate or total protein-thiol levels, paralleled the free radical levels in the brain of all four groups. This suggests PrxI inhibition may be more sensitive indicator of oxidative stress than measuring free radicals or metabolites. As PrxI oxidation in WC, Wg, and EC rats was reversible, while PrxI oxidation in Eg rats was not, we suggest that alcohol drinking and gp120 together hyperoxidized and inactivated PrxI that suppressed free radical neutralization in the brain of Eg rats. In conclusion, chronic alcohol drinking, by carbonylating and hyperoxidizing free radical neutralization proteins, augmented the gp120-induced oxidative stress that may be associated with an increase in severity of the brain neuropathy.

  12. Peroxiredoxin 3 maintains the survival of endometrial cancer stem cells by regulating oxidative stress.

    Science.gov (United States)

    Song, In-Sung; Jeong, Yu Jeong; Seo, Young Jin; Byun, Jung Mi; Kim, Young Nanm; Jeong, Dae Hoon; Han, Jin; Kim, Ki Tae; Jang, Sung-Wuk

    2017-11-03

    Cancer stem cell (CSC)-targeted therapy could reduce tumor growth, recurrence, and metastasis in endometrial cancer (EC). The mitochondria of CSCs have been recently found to be an important target for cancer treatment, but the mitochondrial features of CSCs and their regulators, which maintain mitochondrial function, remain unclear. Here, we investigated the mitochondrial properties of CSCs, and identified specific targets for eliminating CSCs in EC. We found that endometrial CSCs displayed higher mitochondrial membrane potential, Ca 2+ , reactive oxygen species, ATP levels, and oxygen consumption rates than non-CSCs. Further, we also verified that mitochondrial peroxiredoxin 3 (Prx3) was upregulated, and that it contributed to the survival of CSCs in EC. The knockdown of the Prx3 gene resulted not only in decreased sphere formation, but also reduced the viability of endometrial CSCs, by causing mitochondrial dysfunction. Furthermore, we found that the forkhead box protein M1 (FoxM1), an important transcriptional factor, is overexpressed in patients with EC. FoxM1 expression correlates with elevated Prx3 expression levels, in agreement with the tumorigenic ability of Prx3 in endometrial CSCs. Taken together, our findings indicate that human endometrial CSCs have enhanced mitochondrial function compared to that of endometrial tumor cells. Endometrial CSCs show increased expression of the mitochondrial Prx3, which is required for the maintenance of mitochondrial function and survival, and is induced by FoxM1. Based on our findings, we believe that these proteins might represent valuable therapeutic targets and could provide new insights into the development of new therapeutic strategies for patients with endometrial cancer.

  13. Mobility of the Arg-Gly-Asp ligand on the outermost surface of biomaterials suppresses integrin-mediated mechanotransduction and subsequent cell functions.

    Science.gov (United States)

    Kakinoki, Sachiro; Seo, Ji-Hun; Inoue, Yuuki; Ishihara, Kazuhiko; Yui, Nobuhiko; Yamaoka, Tetsuji

    2015-02-01

    Mechanotransduction in the regulation of cellular responses has been previously studied using elastic hydrogels. Because cells interact only with the surface of biomaterials, we are focusing on the molecular mobility at the outermost surface of biomaterials. In this study, surfaces with the mobile Arg-Gly-Asp-Ser (RGDS) peptide have been constructed. Cell culture substrates were coated with ABA-type block copolymers composed of poly(2-methacryloyloxyethyl phosphorylcholine-co-n-butyl methacrylate) segments (A) and a polyrotaxane (PRX) unit with RGDS bound to α-cyclodextrin (B). Adhesion, morphological changes and actin filament formation of human umbilical vein endothelial cells were reduced on the surfaces containing mobile PRX-RGDS in comparison to the immobile RGDS surfaces constructed from random copolymers with RGDS side groups (Prop-andom-RGDS). In the neurite outgrowth assay using rat adrenal pheochromocytoma cells (PC12), only ∼20% of adherent PC12 cells had neurites on PRX-RGDS surfaces, but more than 50% did on the Random-RGDS surface. The beating colony of dimethyl-sulfoxide-treated mouse embryonic carcinoma cells (P19CL6) were found 10 and 14 days after induction on PRX-RGDS and Random-RGDS surfaces, respectively. After 22 days, the beating colony disappeared on PRX-RGDS surfaces, but many colonies remained on Random-RGDS surfaces. These data suggest that the molecular mobility of the cell-binding ligand on the outermost surface of materials effectively suppresses the actin filament formation and differentiation of these functional cell lines, and may be used as a culture substrate for immature stem cells or progenitor cells. Copyright © 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  14. Regulation of MntH by a dual Mn(II- and Fe(II-dependent transcriptional repressor (DR2539 in Deinococcus radiodurans.

    Directory of Open Access Journals (Sweden)

    Hongxing Sun

    Full Text Available The high intracellular Mn/Fe ratio observed within the bacteria Deinococcus radiodurans may contribute to its remarkable resistance to environmental stresses. We isolated DR2539, a novel regulator of intracellular Mn/Fe homeostasis in D. radiodurans. Electrophoretic gel mobility shift assays (EMSAs revealed that DR2539 binds specifically to the promoter of the manganese acquisition transporter (MntH gene, and that DR0865, the only Fur homologue in D. radiodurans, cannot bind to the promoter of mntH, but it can bind to the promoter of another manganese acquisition transporter, MntABC. β-galactosidase expression analysis indicated that DR2539 acts as a manganese- and iron-dependent transcriptional repressor. Further sequence alignment analysis revealed that DR2539 has evolved some special characteristics. Site-directed mutagenesis suggested that His98 plays an important role in the activities of DR2539, and further protein-DNA binding activity assays showed that the activity of H98Y mutants decreased dramatically relative to wild type DR2539. Our study suggests that D. radiodurans has evolved a very efficient manganese regulation mechanism that involves its high intracellular Mn/Fe ratio and permits resistance to extreme conditions.

  15. Regulation of MntH by a Dual Mn(II)- and Fe(II)-Dependent Transcriptional Repressor (DR2539) in Deinococcus radiodurans

    Science.gov (United States)

    Xu, Guangzhi; Chen, Huan; Jiao, Jiandong; Tian, Bing; Wang, Liangyan; Hua, Yuejin

    2012-01-01

    The high intracellular Mn/Fe ratio observed within the bacteria Deinococcus radiodurans may contribute to its remarkable resistance to environmental stresses. We isolated DR2539, a novel regulator of intracellular Mn/Fe homeostasis in D. radiodurans. Electrophoretic gel mobility shift assays (EMSAs) revealed that DR2539 binds specifically to the promoter of the manganese acquisition transporter (MntH) gene, and that DR0865, the only Fur homologue in D. radiodurans, cannot bind to the promoter of mntH, but it can bind to the promoter of another manganese acquisition transporter, MntABC. β-galactosidase expression analysis indicated that DR2539 acts as a manganese- and iron-dependent transcriptional repressor. Further sequence alignment analysis revealed that DR2539 has evolved some special characteristics. Site-directed mutagenesis suggested that His98 plays an important role in the activities of DR2539, and further protein-DNA binding activity assays showed that the activity of H98Y mutants decreased dramatically relative to wild type DR2539. Our study suggests that D. radiodurans has evolved a very efficient manganese regulation mechanism that involves its high intracellular Mn/Fe ratio and permits resistance to extreme conditions. PMID:22523570

  16. Increased localized delivery of piroxicam by cationic nanoparticles after intra-articular injection

    Directory of Open Access Journals (Sweden)

    Kim SR

    2016-11-01

    Full Text Available Sung Rae Kim,1 Myoung Jin Ho,2 Sang Hyun Kim,1 Ha Ra Cho,2 Han Sol Kim,2 Yong Seok Choi,2 Young Wook Choi,1 Myung Joo Kang2 1Division of Pharmaceutical Sciences, College of Pharmacy, Chung-Ang University, Seoul, 2College of Pharmacy, Dankook University, Cheonan, Chungnam, South Korea Abstract: Piroxicam (PRX, a potent nonsteroidal anti-inflammatory drug, is prescribed to relieve postoperative and/or chronic joint pain. However, its oral administration often results in serious gastrointestinal adverse effects including duodenal ulceration. Thus, a novel cationic nanoparticle (NP was explored to minimize the systemic exposure and increase the retention time of PRX in the joint after intra-articular (IA injection, by forming micrometer-sized electrostatic clusters with endogenous hyaluronic acid (HA in the synovial cavity. PRX-loaded NPs consisting of poly(lactic-co-glycolic acid, Eudragit RL, and polyvinyl alcohol were constructed with the following characteristics: particle size of 220 nm, zeta potential of 11.5 mV in phosphate-buffered saline, and loading amount of 4.0% (w/w of PRX. In optical and hyperspectral observations, the cationic NPs formed more than 50 µm-sized aggregates with HA, which was larger than the intercellular gaps between synoviocytes. In an in vivo pharmacokinetic study in rats, area under the plasma concentration–time curve (AUC0–24 h and maximum plasma concentration (Cmax of PRX after IA injection of the cationic NPs were <70% (P<0.05 and 60% (P<0.05, respectively, compared to those obtained from drug solution. Moreover, the drug concentration in joint tissue 24 h after dosing with the cationic NPs was 3.2-fold (P<0.05 and 1.8-fold (P<0.05 higher than that from drug solution and neutrally charged NPs, respectively. Therefore, we recommend the IA cationic NP therapy as an effective alternative to traditional oral therapy with PRX, as it increases drug retention selectively in the joint. Keywords: piroxicam

  17. Efficient production of (2)H, (13)C, (15)N-enriched industrial enzyme Rhizopus chinensis lipase with native disulfide bonds.

    Science.gov (United States)

    Zhang, Meng; Yu, Xiao-Wei; Swapna, G V T; Xiao, Rong; Zheng, Haiyan; Sha, Chong; Xu, Yan; Montelione, Gaetano T

    2016-07-13

    In order to use most modern methods of NMR spectroscopy to study protein structure and dynamics, isotope-enriched protein samples are essential. Especially for larger proteins (>20 kDa), perdeuterated and Ile (δ1), Leu, and Val methyl-protonated protein samples are required for suppressing nuclear relaxation to provide improved spectral quality, allowing key backbone and side chain resonance assignments needed for protein structure and dynamics studies. Escherichia coli and Pichia pastoris are two of the most popular expression systems for producing isotope-enriched, recombinant protein samples for NMR investigations. The P. pastoris system can be used to produce (13)C, (15)N-enriched and even (2)H,(13)C, (15)N-enriched protein samples, but efficient methods for producing perdeuterated proteins with Ile (δ1), Leu and Val methyl-protonated groups in P. pastoris are still unavailable. Glycosylation heterogeneity also provides challenges to NMR studies. E. coli expression systems are efficient for overexpressing perdeuterated and Ile (δ1), Leu, Val methyl-protonated protein samples, but are generally not successful for producing secreted eukaryotic proteins with native disulfide bonds. The 33 kDa protein-Rhizopus chinensis lipase (RCL), an important industrial enzyme, was produced using both P. pastoris and E. coli BL21 trxB (DE3) systems. Samples produced from both systems exhibit identical native disulfide bond formation and similar 2D NMR spectra, indicating similar native protein folding. The yield of (13)C, (15)N-enriched r27RCL produced using P. pastoris was 1.7 times higher that obtained using E. coli, while the isotope-labeling efficiency was ~15 % lower. Protein samples produced in P. pastoris exhibit O-glycosylation, while the protein samples produced in E. coli were not glycosylated. The specific activity of r27RCL from P. pastoris was ~1.4 times higher than that produced in E. coli. These data demonstrate efficient production of (2)H, (13)C, (15)N

  18. ANALISIS KUALITAS JARINGAN GPON PADA LAYANAN IPTV PT. TELKOM DI DAERAH DENPASAR, BALI

    Directory of Open Access Journals (Sweden)

    Ngakan Oka Pramundia

    2015-10-01

    Full Text Available GPON adalah sebuah teknologi berbasis fiber optik. PT.TELKOM menerapkan teknologi GPON sebagai jaringan access network untuk layanan IPTV Usee TV. Penelitian ini membahas kualitas jaringan GPON pada layanan IPTV di daerah Denpasar, Bali mengacu pada topologi dan standarisasi kualitas jaringan. Kualitas jaringan dikategorikan baik untuk 3 parameter yaitu Rx Power(Prx, Attenuatiion, dan Attainable Rate. Untuk Rx Power (Prx nilai berkisar antara -18 dBm sampai dengan -24 dBm. Pada Attenuation klasifikasi kualitas jaringannya termasuk pada kategori Excellent. Sedangkan untuk Attainable Rate-nya nilai downstream berkisar antara 2 Gbps sampai dengan 2.4 Gbps. Dengan nilai downstream tersebut dapat memenuhi kebutuhan layanan Usee TV. Hal ini menyatakan bahwa GPON PT.TELKOM sudah mampu melayani layanan IPTV UseeTV di daerah Denpasar, Bali dengan baik

  19. Peroxireduxin-4 is Over-Expressed in Colon Cancer and its Down-Regulation Leads to Apoptosis

    Directory of Open Access Journals (Sweden)

    Sandra M. Leydold

    2011-01-01

    Full Text Available The objective of this study was to gain insight into the biological basis of colon cancer progression by characterizing gene expression differences between normal colon epithelium, corresponding colorectal primary tumors and metastases. We found a close similarity in gene expression patterns between primary tumors and metastases, indicating a correlation between gene expression and morphological characteristics. PRDX4 was identified as highly expressed both in primary colon tumors and metastases, and selected for further characterization. Our study revealed that “Prdx4” (PrxIV, AOE372 shows functional similarities to other Prx family members by negatively affecting apoptosis induction in tumor cells. In addition, our study links Prdx4 with Hif-1α, a key regulatory factor of angiogenesis. Targeting Prdx4 may be an attractive approach in cancer therapy, as its inhibition is expected to lead to induction of apoptosis and blockage of Hif-1α-mediated tumor angiogenesis.

  20. Determination of the Resistance of Cone-Shaped Solid Electrodes

    DEFF Research Database (Denmark)

    Frandsen, Henrik Lund; Hendriksen, Peter Vang; Koch, Søren

    2017-01-01

    during processing can be avoided. Newman's formula for current constriction in the electrolyte is then used to deduce the active contact area based on the ohmic resistance of the cell, and from this the surface specific electro-catalytic activity. However, for electrode materials with low electrical...... conductivity (like Ce1-xPrxO2-δ), the resistance of the cell is significantly influenced by the ohmic resistance of the cone electrode, wherefore it must be included. In this work the ohmic resistance of a cone is modelled analytically based on simplified geometries. The two analytical models only differ...... by a model specific pre-factor, which is consequently determined by a finite element model. The model was applied to measurements on cones of Ce1-xPrxO2-δ  characterized on an YSZ electrolyte. Conclusively, the finite element model was used to obtain a formula for the resistance for different cone angles...

  1. Expression of a defence-related intercellular barley peroxidase in transgenic tobacco

    DEFF Research Database (Denmark)

    Kristensen, B.K.; Brandt, J.; Bojsen, K.

    1997-01-01

    genetically, phenotypically and biochemically. The T-DNA was steadily inherited through three generations. The barley peroxidase is expressed and sorted to the intercellular space in the transgenic tobacco plants. The peroxidase can be extracted from the intercellular space in two molecular forms from both...... barley and transgenic tobacco. The tobacco expressed forms are indistinguishable from the barley expressed forms as determined by analytical isoelectric focusing (pI 8.5) and Western-blotting. Staining for N-glycosylation showed that one form only was glycosylated. The N-terminus of purified Prx8 from...... transgenic tobacco was blocked by pyroglutamate, after the removal of which, N-terminal sequencing verified the transit signal-peptide cleavage site deduced from the cDNA sequence. Phenotype comparisons show that the constitutive expression of Prx8 lead to growth retardation. However, an infection assay...

  2. Pressure autoregulation monitoring and cerebral perfusion pressure target recommendation in patients with severe traumatic brain injury based on minute-by-minute monitoring data.

    Science.gov (United States)

    Depreitere, Bart; Güiza, Fabian; Van den Berghe, Greet; Schuhmann, Martin U; Maier, Gottlieb; Piper, Ian; Meyfroidt, Geert

    2014-06-01

    In severe traumatic brain injury, a universal target for cerebral perfusion pressure (CPP) has been abandoned. Attempts to identify a dynamic CPP target based on the patient's cerebrovascular autoregulatory capacity have been promising so far. Bedside monitoring of pressure autoregulatory capacity has become possible by a number of methods, Czosnyka's pressure reactivity index (PRx) being the most frequently used. The PRx is calculated as the moving correlation coefficient between 40 consecutive 5-second averages of intracranial pressure (ICP) and mean arterial blood pressure (MABP) values. Plotting PRx against CPP produces a U-shaped curve in roughly two-thirds of monitoring time, with the bottom of this curve representing a CPP range corresponding with optimal autoregulatory capacity (CPPopt). In retrospective series, keeping CPP close to CPPopt corresponded with better outcomes. Monitoring of PRx requires high-frequency signal processing. The aim of the present study is to investigate how the processing of the information on cerebrovascular pressure reactivity that can be obtained from routine minute-by-minute ICP and MABP data can be enhanced to enable CPPopt recommendations that do not differ from those obtained by the PRx method, show the same associations with outcome, and can be generated in more than two-thirds of monitoring time. The low-frequency autoregulation index (LAx) was defined as the moving minute-by-minute ICP/MABP correlation coefficient calculated over time intervals varying from 3 to 120 minutes. The CPPopt calculation was based on LAx-CPP plots and done for time windows between 1 and 24 hours and for each LAx type. The resulting matrix of CPPopts were then averaged in a weighted manner, with the weight based on the goodness of fit of a U-shape and the lower value of the LAx corresponding to the U-bottom, to result in a final CPPopt recommendation. The association between actual CPP/CPPopt and outcome was assessed in the multicenter Brain

  3. The Role of Peroxiredoxins in the Transduction of H2O2 Signals.

    Science.gov (United States)

    Rhee, Sue Goo; Woo, Hyun Ae; Kang, Dongmin

    2017-07-10

    Hydrogen peroxide (H2O2) is produced on stimulation of many cell surface receptors and serves as an intracellular messenger in the regulation of diverse physiological events, mostly by oxidizing cysteine residues of effector proteins. Mammalian cells express multiple H2O2-eliminating enzymes, including catalase, glutathione peroxidase (GPx), and peroxiredoxin (Prx). A conserved cysteine in Prx family members is the site of oxidation by H2O2. Peroxiredoxins possess a high-affinity binding site for H2O2 that is lacking in catalase and GPx and which renders the catalytic cysteine highly susceptible to oxidation, with a rate constant several orders of magnitude greater than that for oxidation of cysteine in most H2O2 effector proteins. Moreover, Prxs are abundant and present in all subcellular compartments. The cysteines of most H2O2 effectors are therefore at a competitive disadvantage for reaction with H2O2. Recent Advances: Here we review intracellular sources of H2O2 as well as H2O2 target proteins classified according to biochemical and cellular function. We then highlight two strategies implemented by cells to overcome the kinetic disadvantage of most target proteins with regard to H2O2-mediated oxidation: transient inactivation of local Prx molecules via phosphorylation, and indirect oxidation of target cysteines via oxidized Prx. Critical Issues and Future Directions: Recent studies suggest that only a small fraction of the total pools of Prxs and H2O2 effector proteins localized in specific subcellular compartments participates in H2O2 signaling. Development of sensitive tools to selectively detect phosphorylated Prxs and oxidized effector proteins is needed to provide further insight into H2O2 signaling. Antioxid. Redox Signal. 00, 000-000.

  4. AcEST: BP921423 [AcEST

    Lifescience Database Archive (English)

    Full Text Available RAX_RAT Periaxin OS=Rattus norvegicus GN=Prx PE=1 SV=2 29 7.5 sp|Q7PC62|HOAE1_PSEU2 Effector protein hopAE1 ...OS=Pseudomonas syr... 29 7.5 sp|A8ARN4|LIGB_CITK8 DNA ligase B OS=Citrobacter koseri (strain ... 29 9.8 sp|Q48DU8|HOAE1_PSE14 Effecto

  5. The antiandrogenic effect of finasteride against a mutant androgen receptor

    Science.gov (United States)

    Chhipa, Rishi Raj; Zhang, Haitao; Ip, Clement

    2011-01-01

    Finasteride is known to inhibit Type 2 5α-reductase and thus block the conversion of testosterone to dihydrotestosterone (DHT). The structural similarity of finasteride to DHT raises the possibility that finasteride may also interfere with the function of the androgen receptor (AR). Experiments were carried out to evaluate the antiandrogenic effect of finasteride in LNCaP, C4-2 and VCaP human prostate cancer cells. Finasteride decreased DHT binding to AR, and DHT-stimulated AR activity and cell growth in LNCaP and C4-2 cells, but not in VCaP cells. LNCaP and C4-2 (derived from castration-resistant LNCaP) cells express the T877A mutant AR, while VCaP cells express the wild-type AR. When PC-3 cells, which are AR-null, were transfected with either the wild-type or the T877A mutant AR, only the mutant AR-expressing cells were sensitive to finasteride inhibition of DHT binding. Peroxiredoxin-1 (Prx1) is a novel endogenous facilitator of AR binding to DHT. In Prx1-rich LNCaP cells, the combination of Prx1 knockdown and finasteride was found to produce a greater inhibitory effect on AR activity and cell growth than either treatment alone. The observation suggests that cells with a low expression of Prx1 are likely to be more responsive to the antiandrogenic effect of finasteride. Additional studies showed that the efficacy of finasteride was comparable to that of bicalutamide (a widely used non-steroidal antiandrogen). The implication of the above findings is discussed in the context of developing strategies to improve the outcome of androgen deprivation therapy. PMID:21386657

  6. Isozyme characterization of Capsicum accessions from the Amazonian Colombian collection Caracterización por isoenzimas de accesiones de Capsicum pertenecientes a la colección amazónica Colombiana

    OpenAIRE

    Melgarejo Luz Marina; Giraldo Martha Cecilia; García Marisol Cudris; Quintero Barrera Lorena

    2005-01-01

    Two hundred and sixty-one accessions of the genus Capsicum were obtained from the Colombian Amazonian germplasm bank at Amazonian Institute of Scientific Research (Sinchi) and were evaluated with five polymorphic enzymatic systems, including esterase (EST), peroxidase (PRX), 6-phosphogluconate dehydrogenase (6-PGDH), aspartate amino transferase (GOT), and malic enzyme (ME). Using a cluster analysis (UPGMA) the genetic variability of these accessions were characterized. Grouping of the species...

  7. Electrochemical reduction of oxygen and nitric oxide at low temperature on Ce1−xPrxO2−δ cathodes

    DEFF Research Database (Denmark)

    Werchmeister, Rebecka Maria Larsen; Kammer Hansen, Kent

    2013-01-01

    The ability of praseodymium doped cerium oxide materials to electrochemically reduce NO and O2 was studied using cone-shaped electrodes in conjunction with cyclic voltammetry, in the temperature range 200–400 °C. Four samples were studied; Ce1−xPrxO2−δ (x = 0.1, 0.2, 0.3 and 0.4). It was shown th...

  8. The effects of chromium(VI) on the thioredoxin system: Implications for redox regulation

    Science.gov (United States)

    Myers, Charles R.

    2014-01-01

    Hexavalent chromium [Cr(VI)] compounds are highly redox active and have long been recognized as potent cytotoxins and carcinogens. The intracellular reduction of Cr(VI) generates reactive Cr intermediates, which are themselves strong oxidants, as well as superoxide, hydrogen peroxide, and hydroxyl radical. These probably contribute to the oxidative damage and effects on redox-sensitive transcription factors that have been reported. However, the identification of events that initiate these signaling changes has been elusive. More recent studies show that Cr(VI) causes irreversible inhibition of thioredoxin reductase (TrxR) and oxidation of thioredoxin (Trx) and peroxiredoxin (Prx). Mitochondrial Trx2/Prx3 are more sensitive to Cr(VI) treatment than cytosolic Trx1/Prx1, although both compartments show thiol oxidation with higher doses or longer treatments. Thiol redox proteomics demonstrate that Trx2, Prx3, and Trx1 are among the most sensitive proteins in cells to Cr(VI) treatment. Their oxidation could therefore represent initiating events that have widespread implications for protein thiol redox control and for multiple aspects of redox signaling. This review summarizes the effects of Cr(VI) on the TrxR/Trx system and how these events could influence a number of downstream redox signaling systems that are influenced by Cr(VI) exposure. Some of the signaling events discussed include the activation of apoptosis signal regulating kinase and MAP kinases (p38 and JNK) and the modulation of a number of redox-sensitive transcription factors including AP-1, NF-κB, p53, and Nrf2. PMID:22542445

  9. Sex-Dependent, Osteoblast Stage-Specific Effects of Progesterone Receptor on Bone Acquisition.

    Science.gov (United States)

    Zhong, Zhendong A; Kot, Alexander; Lay, Yu-An E; Zhang, Hongliang; Jia, Junjing; Lane, Nancy E; Yao, Wei

    2017-09-01

    The role of the progesterone receptor (PR) in the regulation of sexual dimorphism in bone has yet to be determined. Here we utilized genetic fate mapping and Western blotting to demonstrate age-dependent PR expression in the mouse femoral metaphysis and diaphysis. To define sex-dependent and osteoblast stage-specific effects of PR on bone acquisition, we selectively deleted PR at different stages of osteoblast differentiation. We found that when Prx1-Cre mice were crossed with PR floxed mice to generate a mesenchymal stem cell (MSC) conditional KO model (Prx1; PRcKO), the mutant mice developed greater trabecular bone volume with higher mineral apposition rate and bone formation. This may be explained by increased number of MSCs and greater osteogenic potential, particularly in males. Age-related trabecular bone loss was similar between the Prx1; PRcKO mice and their WT littermates in both sexes. Hormone deficiency during the period of rapid bone growth induced rapid trabecular bone loss in both the WT and the Prx1; PRcKO mice in both sexes. No differences in trabecular bone mass was observed when PR was deleted in mature osteoblasts using osteocalcin-Cre (Bglap-Cre). Also, there were no differences in cortical bone mass in all three PRcKO mice. In conclusion, PR inactivation in early osteoprogenitor cells but not in mature osteoblasts influenced trabecular bone accrual in a sex-dependent manner. PR deletion in osteoblast lineage cells did not affect cortical bone mass. © 2017 American Society for Bone and Mineral Research. © 2017 American Society for Bone and Mineral Research.

  10. Crystal structure of an archaeal peroxiredoxin from the aerobic hyperthermophilic crenarchaeon Aeropyrum pernix K1.

    Science.gov (United States)

    Mizohata, Eiichi; Sakai, Hiroaki; Fusatomi, Emiko; Terada, Takaho; Murayama, Kazutaka; Shirouzu, Mikako; Yokoyama, Shigeyuki

    2005-11-25

    Peroxiredoxins (Prxs) are thiol-dependent peroxidases that catalyze the detoxification of various peroxide substrates such as H2O2, peroxinitrite, and hydroperoxides, and control some signal transduction in eukaryotic cells. Prxs are found in all cellular organisms and represent an enormous superfamily. Recent genome sequencing projects and biochemical studies have identified a novel subfamily, the archaeal Prxs. Their primary sequences are similar to those of the 1-Cys Prxs, which use only one cysteine residue in catalysis, while their catalytic properties resemble those of the typical 2-Cys Prxs, which utilize two cysteine residues from adjacent monomers within a dimer in catalysis. We present here the X-ray crystal structure of an archaeal Prx from the aerobic hyperthermophilic crenarchaeon, Aeropyrum pernix K1, determined at 2.3 A resolution (Rwork of 17.8% and Rfree of 23.0%). The overall subunit arrangement of the A.pernix archaeal Prx is a toroid-shaped pentamer of homodimers, or an (alpha2)5 decamer, as observed in the previously reported crystal structures of decameric Prxs. The basic folding topology and the peroxidatic active site structure are essentially the same as those of the 1-Cys Prx, hORF6, except that the C-terminal extension of the A.pernix archaeal Prx forms a unique helix with its flanking loops. The thiol group of the peroxidatic cysteine C50 is overoxidized to sulfonic acid. Notably, the resolving cysteine C213 forms the intra-monomer disulfide bond with the third cysteine, C207, which should be a unique structural characteristic in the many archaeal Prxs that retain two conserved cysteine residues in the C-terminal region. The conformational flexibility near the intra-monomer disulfide linkage might be necessary for the dramatic structural rearrangements that occur in the catalytic cycle.

  11. Optimization of transient expression procedures in Catharanthus roseus and Arabidopsis thaliana for subcellular localization studies

    OpenAIRE

    Ribeiro, Diana Margarida da Costa

    2010-01-01

    Dissertação de mestrado em Biotecnologia e Bio-Empreendedorismo em Plantas Aromáticas e Medicinais Nowadays, the availability of much gene sequence information demands the development of tools for their fast characterization at the protein level, where function actually resides. Here, the interest in the characterization of certain of the known Arabidopsis class III peroxidase (Prx) genes, as well as the interest in the characterization of candidate genes implicated in the meta...

  12. Effect of mannitol on cerebrovascular pressure reactivity in patients with intracranial hypertension.

    Science.gov (United States)

    Tang, Sung-Chun; Lin, Ru-Jen; Shieh, Jiann-Shing; Wu, An-Yeu; Lai, Dar-Ming; Huang, Sheng-Jean; Jeng, Jiann-Shing

    2015-09-01

    Mannitol is commonly used in patients with increased intracranial pressure (ICP), but its effect on cerebrovascular pressure reactivity (CVPR) is uncertain. We analyzed the changes of pressure reactivity index (PRx) during the course of mannitol treatment. Twenty-one patients who received mannitol treatment for increased ICP were recruited prospectively. Continuous waveforms of arterial blood pressure (ABP) and ICP were collected simultaneously for 60 minutes (10 minutes at baseline and 50 minutes since mannitol administration) during 37 events of mannitol treatment. The correlation coefficients between the mean ABP and ICP were averaged every 10 minutes and labeled as the PRx. The linear correlation of six time points of PRx in each event was calculated to represent the trend of CVPR changes. The negative slope of correlation was defined as improvement in CVPR under mannitol treatment and vice versa. At baseline, the average of ICP was 26.0 ± 9.1 mmHg and the values of PRx were significantly correlated with ICP (p = 0.0044, r = 0.46). After mannitol administration, the average of ICP decreased significantly to 21.2 ± 11.1 mmHg (p = 0.036), and CVPR improved in 59.4 % of all events. Further analysis showed that low baseline cerebral perfusion pressure was the only hemodynamic parameter significant association with the improvement of CVPR after mannitol treatment (p = 0.039). Despite lowering ICP, mannitol may have diverse effects on CVPR in patients with intracranial hypertension. Our study suggests that mannitol infusion may have a beneficial effect on CVPR, particularly in those with a low cerebral perfusion pressure at baseline. Copyright © 2013. Published by Elsevier B.V.

  13. Further Controversies About Brain Tissue Oxygenation Pressure-Reactivity After Traumatic Brain Injury

    DEFF Research Database (Denmark)

    Andresen, Morten; Donnelly, Joseph; Aries, Marcel

    2017-01-01

    arterial pressure and intracranial pressure. A new ORx index based on brain tissue oxygenation and cerebral perfusion pressure (CPP) has been proposed that similarly allows for evaluation of cerebrovascular reactivity. Conflicting results exist concerning its clinical utility. METHODS: Retrospective....... Higher mortality related to average CPP regardless of which index was used to calculate CPPopt. CONCLUSION: In the TBI setting, ORx does not appear to correlate with vascular pressure reactivity as assessed with PRx. Its potential use for individualizing CPP thresholds remains unclear....

  14. Peroxiredoxins: A Model for a Self-Assembling Nanoscale System

    Science.gov (United States)

    2014-08-24

    sulfataricus SAXS small angle x- ray scattering SDS sodium dodecyl sulfate SEC size exclusion chromatography T, Thr threonine T...transmission electron microscopy Tet tetracyclin TEV tobacco etch virus Tpx thiol peroxidise UV ultraviolet w/v weight/volume Y, Tyr...exist in plants and yeast. The name comes from bacterioferritin comigratory protein, a former name for peroxireodoxins, and the plant PrxQ. Many of

  15. Catalytic Thr or Ser Residue Modulates Structural Switches in 2-Cys Peroxiredoxin by Distinct Mechanisms.

    Science.gov (United States)

    Tairum, Carlos A; Santos, Melina Cardoso; Breyer, Carlos A; Geyer, R Ryan; Nieves, Cecilia J; Portillo-Ledesma, Stephanie; Ferrer-Sueta, Gerardo; Toledo, José Carlos; Toyama, Marcos H; Augusto, Ohara; Netto, Luis E S; de Oliveira, Marcos A

    2016-09-15

    Typical 2-Cys Peroxiredoxins (2-Cys Prxs) reduce hydroperoxides with extraordinary rates due to an active site composed of a catalytic triad, containing a peroxidatic cysteine (CP), an Arg, and a Thr (or Ser). 2-Cys Prx are involved in processes such as cancer; neurodegeneration and host-pathogen interactions. During catalysis, 2-Cys Prxs switch between decamers and dimers. Analysis of 2-Cys Prx structures in the fully folded (but not locally unfolded) form revealed a highly conserved, non-conventional hydrogen bond (CH-π) between the catalytic triad Thr of a dimer with an aromatic residue of an adjacent dimer. In contrast, structures of 2-Cys Prxs with a Ser in place of the Thr do not display this CH-π bond. Chromatographic and structural data indicate that the Thr (but not Ser) destabilizes the decamer structure in the oxidized state probably through steric hindrance. As a general trend, mutations in a yeast 2-Cys Prx (Tsa1) favoring the dimeric state also displayed a decreased catalytic activity. Remarkably, yeast naturally contains Thr-Ser variants (Tsa1 and Tsa2, respectively) with distinct oligomeric stabilities in their disulfide states.

  16. The Role of Redox-Regulating Enzymes in Inoperable Breast Cancers Treated with Neoadjuvant Chemotherapy

    Directory of Open Access Journals (Sweden)

    Nelli Roininen

    2017-01-01

    Full Text Available Although validated predictive factors for breast cancer chemoresistance are scarce, there is emerging evidence that the induction of certain redox-regulating enzymes may contribute to a poor chemotherapy effect. We investigated the possible association between chemoresistance and cellular redox state regulation in patients undergoing neoadjuvant chemotherapy (NACT for breast cancer. In total, 53 women with primarily inoperable or inflammatory breast cancer who were treated with NACT were included in the study. Pre-NACT core needle biopsies and postoperative tumor samples were immunohistochemically stained for nuclear factor erythroid 2-related factor 2 (Nrf2, Kelch-like ECH-associated protein 1 (Keap1, thioredoxin (Trx, and peroxiredoxin I (Prx I. The expression of all studied markers increased during NACT. Higher pre-NACT nuclear Prx I expression predicted smaller size of a resected tumor (p=0.00052; r=−0.550, and higher pre-NACT cytoplasmic Prx I expression predicted a lower amount of evacuated nodal metastasis (p=0.0024; r=−0.472. Pre-NACT nuclear Trx expression and pre-NACT nuclear Keap1 expression had only a minor prognostic significance as separate factors, but when they were combined, low expression for both antibodies before NACT predicted dismal disease-free survival (log-rank p=0.0030. Our results suggest that redox-regulating enzymes may serve as potential prognostic factors in primarily inoperable breast cancer patients.

  17. Novel metabolic biomarkers related to sulfur-dependent detoxification pathways in autistic patients of Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Al- Ayadhi Laila Y

    2011-11-01

    Full Text Available Abstract Background Xenobiotics are neurotoxins that dramatically alter the health of the child. In addition, an inefficient detoxification system leads to oxidative stress, gut dysbiosis, and immune dysfunction. The consensus among physicians who treat autism with a biomedical approach is that those on the spectrum are burdened with oxidative stress and immune problems. In a trial to understand the role of detoxification in the etiology of autism, selected parameters related to sulfur-dependent detoxification mechanisms in plasma of autistic children from Saudi Arabia will be investigated compared to control subjects. Methods 20 males autistic children aged 3-15 years and 20 age and gender matching healthy children as control group were included in this study. Levels of reduced glutathione (GSH, total (GSH+GSSG, glutathione status (GSH/GSSG, glutathione reductase (GR, glutathione- s-transferase (GST, thioredoxin (Trx, thioredoxin reductase (TrxR and peroxidoxins (Prxs I and III were determined. Results Reduced glutathione, total glutathione, GSH/GSSG and activity levels of GST were significantly lower, GR shows non-significant differences, while, Trx, TrxR and both Prx I and III recorded a remarkably higher values in autistics compared to control subjects. Conclusion The impaired glutathione status together with the elevated Trx and TrxR and the remarkable over expression of both Prx I and Prx III, could be used as diagnostic biomarkers of autism.

  18. Repeated Superovulation via PMSG/hCG Administration Induces 2-Cys Peroxiredoxins Expression and Overoxidation in the Reproductive Tracts of Female Mice.

    Science.gov (United States)

    Park, Sun-Ji; Kim, Tae-Shin; Kim, Jin-Man; Chang, Kyu-Tae; Lee, Hyun-Shik; Lee, Dong-Seok

    2015-12-01

    Superovulation induced by exogenous gonadotropin treatment (PMSG/hCG) increases the number of available oocytes in humans and animals. However, Superovulatory PMSG/hCG treatment is known to affect maternal environment, and these effects may result from PMSG/hCG treatment-induced oxidative stress. 2-Cys peroxiredoxins (2-Cys Prxs) act as antioxidant enzymes that protect cells from oxidative stress induced by various exogenous stimuli. Therefore, the objective of this study was to test the hypothesis that repeated PMSG/hCG treatment induces 2-Cys Prx expression and overoxidation in the reproductive tracts of female mice. Immunohistochemistry and western blotting analyses further demonstrated that, after PMSG/hCG treatment, the protein expression levels of 2-Cys Prxs increased most significantly in the ovaries, while that of Prx1 was most affected by PMSG/hCG stimulation in all tissues of the female reproductive tract. Repeated PMSG/hCG treatment eventually leads to 2-Cys Prxs overoxidation in all reproductive organs of female mice, and the abundance of the 2-Cys Prxs-SO2/3 proteins reported here supports the hypothesis that repeated superovulation induces strong oxidative stress and damage to the female reproductive tract. Our data suggest that excessive oxidative stress caused by repeated PMSG/hCG stimulation increases 2-Cys Prxs expression and overoxidation in the female reproductive organs. Intracellular 2-Cys Prx therefore plays an important role in maintaining the reproductive organ environment of female mice upon exogenous gonadotropin treatment.

  19. Towards improved solubility of poorly water-soluble drugs: cryogenic co-grinding of piroxicam with carrier polymers.

    Science.gov (United States)

    Penkina, Anna; Semjonov, Kristian; Hakola, Maija; Vuorinen, Sirpa; Repo, Timo; Yliruusi, Jouko; Aruväli, Jaan; Kogermann, Karin; Veski, Peep; Heinämäki, Jyrki

    2016-01-01

    Amorphous solid dispersions (SDs) open up exciting opportunities in formulating poorly water-soluble active pharmaceutical ingredients (APIs). In the present study, novel catalytic pretreated softwood cellulose (CPSC) and polyvinylpyrrolidone (PVP) were investigated as carrier polymers for preparing and stabilizing cryogenic co-ground SDs of poorly water-soluble piroxicam (PRX). CPSC was isolated from pine wood (Pinus sylvestris). Raman and Fourier transform infrared (FTIR) spectroscopy, X-ray powder diffraction (XRPD) and differential scanning calorimetry (DSC) were used for characterizing the solid-state changes and drug-polymer interactions. High-resolution scanning electron microscope (SEM) was used to analyze the particle size and surface morphology of starting materials and final cryogenic co-ground SDs. In addition, the molecular aspects of drug-polymer interactions and stabilization mechanisms are presented. The results showed that the carrier polymer influenced both the degree of amorphization of PRX and stabilization against crystallization. The cryogenic co-ground SDs prepared from PVP showed an enhanced dissolution rate of PRX, while the corresponding SDs prepared from CPSC exhibited a clear sustained release behavior. In conclusion, cryogenic co-grinding provides a versatile method for preparing amorphous SDs of poorly water-soluble APIs. The solid-state stability and dissolution behavior of such co-ground SDs are to a great extent dependent on the carrier polymer used.

  20. Development of Oromucosal Dosage Forms by Combining Electrospinning and Inkjet Printing.

    Science.gov (United States)

    Palo, Mirja; Kogermann, Karin; Laidmäe, Ivo; Meos, Andres; Preis, Maren; Heinämäki, Jyrki; Sandler, Niklas

    2017-03-06

    Printing technology has been shown to enable flexible fabrication of solid dosage forms for personalized drug therapy. Several methods can be applied for tailoring the properties of the printed pharmaceuticals. In this study, the use of electrospun fibrous substrates in the fabrication of inkjet-printed dosage forms was investigated. A single-drug formulation with lidocaine hydrochloride (LH) and a combination drug system containing LH and piroxicam (PRX) for oromucosal administration were prepared. The LH was deposited on the electrospun and cross-linked gelatin substrates by inkjet printing, whereas PRX was incorporated within the substrate fibers during electrospinning. The solid state analysis of the electrospun substrates showed that PRX was in an amorphous state within the fibers. Furthermore, the results indicated the entrapment and solidification of the dissolved LH within the fibrous gelatin matrix. The printed drug amount (2-3 mg) was in good correlation with the theoretical dose calculated based on the printing parameters. However, a noticeable degradation of the printed LH was detected after a few months. An immediate release (over 85% drug release after 8 min) of both drugs from the printed dosage forms was observed. In conclusion, the prepared electrospun gelatin scaffolds were shown to be suitable substrates for inkjet printing of oromucosal formulations. The combination of electrospinning and inkjet printing allowed the preparation of a dual drug system.

  1. Dynamic Cerebrovascular and Intracranial Pressure Reactivity Assessment of Impaired Cerebrovascular Autoregulation in Intracranial Hypertension.

    Science.gov (United States)

    Bragin, Denis E; Statom, Gloria; Nemoto, Edwin M

    2016-01-01

    We previously suggested that the discrepancy between a critical cerebral perfusion pressure (CPP) of 30 mmHg, obtained by increasing intracranial pressure (ICP), and 60 mmHg, obtained by decreasing arterial pressure, was due to pathological microvascular shunting at high ICP [1], and that the determination of the critical CPP by the static cerebral blood flow (CBF) autoregulation curve is not valid with intracranial hypertension. Here, we demonstrated that induced dynamic ICP reactivity (iPRx), and cerebrovascular reactivity (CVRx) tests accurately identify the critical CPP in the hypertensive rat brain, which differs from that obtained by the static autoregulation curve. Step changes in CPP from 70 to 50 and 30 mmHg were made by increasing ICP using an artificial cerebrospinal fluid reservoir connected to the cisterna magna. At each CPP, a transient 10-mmHg increase in arterial pressure was induced by bolus intravenous dopamine. iPRx and iCVRx were calculated as ΔICP/Δ mean arterial pressure (MAP) and as ΔCBF/ΔMAP, respectively. The critical CPP at high ICP, obtained by iPRx and iCVRx, is 50 mmHg, where compromised capillary flow, transition of blood flow to nonnutritive microvascular shunts, tissue hypoxia, and brain-blood barrier leakage begin to occur, which is higher than the 30 mmHg determined by static autoregulation.

  2. Treatment of erythrocytes with the 2-cys peroxiredoxin inhibitor, Conoidin A, prevents the growth of Plasmodium falciparum and enhances parasite sensitivity to chloroquine.

    Directory of Open Access Journals (Sweden)

    Mariana Brizuela

    Full Text Available The human erythrocyte contains an abundance of the thiol-dependant peroxidase Peroxiredoxin-2 (Prx2, which protects the cell from the pro-oxidant environment it encounters during its 120 days of life in the blood stream. In malarial infections, the Plasmodium parasite invades red cells and imports Prx2 during intraerythrocytic development, presumably to supplement in its own degradation of peroxides generated during cell metabolism, especially hemoglobin (Hb digestion. Here we demonstrate that an irreversible Prx2 inhibitor, Conoidin A (2,3-bis(bromomethyl-1,4-dioxide-quinoxaline; BBMQ, has potent cytocidal activity against cultured P. falciparum. Parasite growth was also inhibited in red cells that were treated with BBMQ and then washed prior to parasite infection. These cells remained susceptible to merozoite invasion, but failed to support normal intraerythrocytic development. In addition the potency of chloroquine (CQ, an antimalarial drug that prevents the detoxification of Hb-derived heme, was significantly enhanced in the presence of BBMQ. CQ IC50 values decreased an order of magnitude when parasites were either co-incubated with BBMQ, or introduced into BBMQ-pretreated cells; these effects were equivalent for both drug-resistant and drug-sensitive parasite lines. Together these results indicate that treatment of red cells with BBMQ renders them incapable of supporting parasite growth and increases parasite sensitivity to CQ. We also propose that molecules such as BBMQ that target host cell proteins may constitute a novel host-directed therapeutic approach for treating malaria.

  3. Homologous overexpression of alkyl hydroperoxide reductase subunit C (ahpC) protects Bifidobacterium longum strain NCC2705 from oxidative stress.

    Science.gov (United States)

    Zuo, FangLei; Yu, Rui; Khaskheli, Gul Bahar; Ma, HuiQin; Chen, LiLi; Zeng, Zhu; Mao, AiJun; Chen, ShangWu

    2014-09-01

    The ability to manage reactive oxygen species (ROS) effectively is crucial for the survival of gut bifidobacteria under conditions of oxidative stress. Alkyl hydroperoxide reductase catalytic subunit C (ahpC) of Bifidobacterium longum responds to various oxidative stresses. In this study, an ahpC-overexpressing transformant of B. longum strain NCC2705 was constructed to investigate the role and function of ahpC in oxidative stresses inflicted by treatments with hydrogen peroxide (H2O2), cumene hydroperoxide, and aerobic oxygen. Results indicated that in B. longum, AhpC is the primary scavenger of endogenous H2O2 generated by aerobic metabolism, but it is unable to detoxify high concentrations of exogenous H2O2. The ahpC-overexpressing B. longum strain showed increased resistance to organic hydroperoxide killing, increased viability under aerobic growth, but decreased resistance to exogenous H2O2 in comparison to the control strain. Analysis of genes from the oxidative stress-defense pathway encoding oxygen-independent coproporphyrinogen III oxidase (HemN), NADH oxidase (Nox) and thioredoxin reductase-like protein (TrxB) showed increased transcript levels in the ahpC-overexpressing vs. control strain. These findings suggest that elevated ahpC expression facilitates or activates the different electron donor-dependent ROS-elimination pathways in B. longum's response to oxidative stress. Copyright © 2014 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

  4. Differential roles for the Co2+/Ni2+ transporting ATPases, CtpD and CtpJ, in Mycobacterium tuberculosis virulence

    Science.gov (United States)

    Raimunda, Daniel; Long, Jarukit E.; Padilla-Benavides, Teresita; Sassetti, Christopher M.; Argüello, José M.

    2013-01-01

    SUMMARY The genome of Mycobacterium tuberculosis encodes two paralogous P1B4-ATPases, CtpD (Rv1469) and CtpJ (Rv3743). Both proteins showed ATPase activation by Co2+ and Ni2+, and both appear to be required for metal efflux from the cell. However, using a combination of biochemical and genetic studies we found that these proteins play nonredundant roles in virulence and metal efflux. CtpJ expression is induced by Co2+ and this protein possesses a relatively high turnover rate. A ctpJ deletion mutant accumulated Co2+, indicating that this ATPase controls cytoplasmic metal levels. In contrast, CtpD expression is induced by redox stressors and this protein displays a relatively low turnover rate. A ctpD mutant failed to accumulate metal, suggesting an alternative cellular function. ctpD is co-transcribed with two thioredoxin genes trxA (Rv1470), trxB (Rv1471), and an enoyl-coA hydratase (Rv1472), indicating a possible role for CtpD in the metallation of these redox-active proteins. Supporting this, in vitro metal binding assays showed that TrxA binds Co2+ and Ni2+. Mutation of ctpD, but not ctpJ, reduced bacterial fitness in the mouse lung, suggesting that redox maintenance, but not Co+2 accumulation, is important for growth in vivo. PMID:24255990

  5. Three-Dimensional Structure and Biophysical Characterization of Staphylococcus aureus Cell Surface Antigen-Manganese Transporter MntC

    Energy Technology Data Exchange (ETDEWEB)

    Gribenko, Alexey; Mosyak, Lidia; Ghosh, Sharmistha; Parris, Kevin; Svenson, Kristine; Moran, Justin; Chu, Ling; Li, Sheng; Liu, Tong; Woods, Jr., Virgil L.; Jansen, Kathrin U.; Green, Bruce A.; Anderson, Annaliesa S.; Matsuka, Yury V. [Pfizer; (UCSD)

    2013-08-23

    MntC is a metal-binding protein component of the Mn2 +-specific mntABC transporter from the pathogen Staphylococcus aureus. The protein is expressed during the early stages of infection and was proven to be effective at reducing both S. aureus and Staphylococcus epidermidis infections in a murine animal model when used as a vaccine antigen. MntC is currently being tested in human clinical trials as a component of a multiantigen vaccine for the prevention of S. aureus infections. To better understand the biological function of MntC, we are providing structural and biophysical characterization of the protein in this work. The three-dimensional structure of the protein was solved by X-ray crystallography at 2.2 Å resolution and suggests two potential metal binding modes, which may lead to reversible as well as irreversible metal binding. Precise Mn2 +-binding affinity of the protein was determined from the isothermal titration calorimetry experiments using a competition approach. Differential scanning calorimetry experiments confirmed that divalent metals can indeed bind to MntC reversibly as well as irreversibly. Finally, Mn2 +-induced structural and dynamics changes have been characterized using spectroscopic methods and deuterium–hydrogen exchange mass spectroscopy. Results of the experiments show that these changes are minimal and are largely restricted to the structural elements involved in metal coordination. Therefore, it is unlikely that antibody binding to this antigen will be affected by the occupancy of the metal-binding site by Mn2 +.

  6. Changes in Cerebral Partial Oxygen Pressure and Cerebrovascular Reactivity During Intracranial Pressure Plateau Waves.

    Science.gov (United States)

    Lang, Erhard W; Kasprowicz, Magdalena; Smielewski, Peter; Pickard, John; Czosnyka, Marek

    2015-08-01

    Plateau waves in intracranial pressure (ICP) are frequently recorded in neuro intensive care and are not yet fully understood. To further investigate this phenomenon, we analyzed partial pressure of cerebral oxygen (pbtO2) and a moving correlation coefficient between ICP and mean arterial blood pressure (ABP), called PRx, along with the cerebral oxygen reactivity index (ORx), which is a moving correlation coefficient between cerebral perfusion pressure (CPP) and pbtO2 in an observational study. We analyzed 55 plateau waves in 20 patients after severe traumatic brain injury. We calculated ABP, ABP pulse amplitude (ampABP), ICP, CPP, pbtO2, heart rate (HR), ICP pulse amplitude (ampICP), PRx, and ORx, before, during, and after each plateau wave. The analysis of variance with Bonferroni post hoc test was used to compare the differences in the variables before, during, and after the plateau wave. We considered all plateau waves, even in the same patient, independent because they are separated by long intervals. We found increases for ICP and ampICP according to our operational definitions for plateau waves. PRx increased significantly (p = 0.00026), CPP (p waves. ABP, ampABP, and HR remained unchanged. PRx during the plateau was higher than before the onset of wave in 40 cases (73 %) with no differences in baseline parameters for those with negative and positive ΔPRx (difference during and after). ORx showed an increase during and a decrease after the plateau waves, however, not statistically significant. PbtO2 overshoot after the wave occurred in 35 times (64 %), the mean difference was 4.9 ± 4.6 Hg (mean ± SD), and we found no difference in baseline parameters between those who overshoot and those who did not overshoot. Arterial blood pressure remains stable in ICP plateau waves, while cerebral autoregulatory indices show distinct changes, which indicate cerebrovascular reactivity impairment at the top of the wave. PbtO2 decreases during the waves and may

  7. A Description of a New Continuous Physiologic Index in TBI using the Correlation Between Pulse Amplitude of ICP and Cerebral Perfusion Pressure.

    Science.gov (United States)

    Zeiler, Frederick Adam; Donnelly, Joseph; Menon, David; Smieleweski, Peter; Hutchinson, Peter John; Czosnyka, Marek

    2017-12-06

    To describe a new continuous index of physiologic measurement in a TBI population, the moving correlation coefficient between intracranial pressure (ICP) pulse amplitude (AMP) and cerebral perfusion pressure (CPP), which we refer to as RAC. We use patient examples of sustained intracranial hypertension, systemic arterial hypotension and plateau waves, as well as the retrospective analysis of 358 non-decompressive craniectomy (DC) traumatic brain injury (TBI) patients with high frequency ICP and ABP data, to explore the relationships of this new index, RAC, with AMP, ICP, CPP, RAP, pressure reactivity index (PRx) and pulse amplitude index (PAx). We compared the RAC-CPP relationship to that observed between CPP and both PRx and PAx. RAC displays temporal responsiveness to sustained increased ICP, arterial hypotension and plateau waves, with positive values found during episodes of high ICP and low CPP. Analysis of AMP versus CPP and AMP versus ICP relationships in data from the entire non-DC cohort, show lower breakpoints for AMP/CPP at CPP= 40 mm Hg; and upper breakpoints for AMP/ICP at ICP=50 to 60 mm Hg. RAC trends to positive values with increasing ICP, particularly with ICP values above the peak in AMP (ICP>50 mm Hg), though it's interpretation requires concomitant interpretation of AMP, RAP and PRx/PAx to determine contributions of compliance and cerebrovascular responsiveness to the changes seen in RAC. There is a parabolic relationship between RAC vs. CPP, with trends towards positive RAC values near (and beyond) limits for low and high CPPs, suggesting that RAC may be used in the determination of optimum CPP (CPPopt). RAC appears to carry information regarding both: cerebrovascular responsiveness and cerebral compliance. This contributes to RAC's uniqueness and complex interpretation. Further prospective clinical studies of RAC in CPP optimum estimation and outcome prediction in TBI are required.

  8. Klotho expression in long bones regulates FGF23 production during renal failure.

    Science.gov (United States)

    Kaludjerovic, Jovana; Komaba, Hirotaka; Sato, Tadatoshi; Erben, Reinhold G; Baron, Roland; Olauson, Hannes; Larsson, Tobias E; Lanske, Beate

    2017-05-01

    Circulating levels of bone-derived fibroblast growth factor 23 (FGF23) increase early during acute and chronic kidney disease and are associated with adverse outcomes. Membrane-bound Klotho acts as a permissive coreceptor for FGF23, and its expression was recently found in osteoblasts/osteocytes. We hypothesized that Klotho in bone cells is part of an autocrine feedback loop that regulates FGF23 expression during renal failure. Thus, we induced renal failure in mice with targeted deletion of Klotho in long bones. Uremic wild-type (KLfl/fl ) and knockout (Prx1-Cre;KLfl/fl ) mice both responded with reduced body weight, kidney atrophy, hyperphosphatemia, and increased bone turnover. Importantly, long bones of Prx1-Cre;KLfl/fl mice but not their axial skeleton failed to increase FGF23 expression as observed in uremic KLfl/fl mice. Consequently, Prx1-Cre;KLfl/fl mice had significantly lower serum FGF23 and parathyroid hormone levels, and higher renal 1-α-hydroxylase expression, serum 1,25-dihydroxyvitamin D, and calcium levels than KLfl/fl mice. These results were confirmed in two independent models of renal failure, adenine diet induced and 5/6 nephrectomy. Moreover, FGF23-treated bone cells required Klotho to increase FGF23 mRNA and ERK phosphorylation. In summary, our novel findings show that Klotho in bone is crucial for inducing FGF23 production upon renal failure. We propose the presence of an autocrine feedback loop in which Klotho senses the need for FGF23.-Kaludjerovic, J., Komaba, H., Sato, T., Erben, R. G., Baron, R., Olauson, H., Larsson, T. E., Lanske, B. Klotho expression in long bones regulates FGF23 production during renal failure. © FASEB.

  9. Oxidation of 2-cys peroxiredoxins in human endothelial cells by hydrogen peroxide, hypochlorous acid, and chloramines.

    Science.gov (United States)

    Stacey, Melissa M; Vissers, Margreet C; Winterbourn, Christine C

    2012-08-01

    Reactive oxygen species released from neutrophils during vascular inflammation could contribute to endothelial dysfunction seen in diseases such as atherosclerosis. Activated neutrophils generate hydrogen peroxide (H(2)O(2)) and hypochlorous acid (HOCl), as well as chloramines that are formed when HOCl reacts with amino compounds. These oxidants preferentially target thiol groups and thiol-containing proteins. The peroxiredoxins (Prxs) are thiol proteins that have high reactivity with H(2)O(2) and may also be sensitive to HOCl and chloramines. We have investigated human umbilical vein endothelial cells and shown that their cytoplasmic (Prx1 and Prx2) and mitochondrial (Prx3) Prxs are oxidized when they are exposed to H(2)O(2), HOCl, or cell-permeable chloramines. H(2)O(2) converted the Prxs to hyperoxidized, inactive forms, with little accumulation of disulfide-linked dimers. The oxidized Prxs were reduced over hours, presumably due to the action of endothelial sulfiredoxin. In contrast to the hyperoxidation seen with H(2)O(2), HOCl and the chloramine derivatives of glycine and ammonia converted the Prxs to disulfide-linked dimers and dimerization was reversed within 10-30 min of oxidant removal. HOCl treatment caused thioredoxin reductase (TrxR) inhibition with no reversal of dimerization. The cytotoxicity of ammonia chloramine was increased when cells were pretreated with H(2)O(2) to hyperoxidize the Prxs, or when the chloramine was added in the presence of the TrxR inhibitor, auranofin. We describe the novel observation that exposure of nucleated cells to inflammatory oxidants results in the accumulation of Prxs in the dimeric form. Endothelial cell Prxs are sensitive targets for neutrophil-derived oxidants and may protect against their damaging effects.

  10. Evaluation of toxicological biomarkers in secreted proteins of HepG2 cells exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin and their expressions in the plasma of rats and incineration workers.

    Science.gov (United States)

    Phark, Sohee; Park, So-Young; Chang, Yoon-Seok; Choi, Seonyoung; Lim, Ji-youn; Kim, Yoonjin; Seo, Jong Bok; Jung, Woon-Won; Sul, Donggeun

    2016-05-01

    Toxicological biomarkers of 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD) were investigated in proteins secreted by HepG2 cells and their expression levels were determined in the plasma of rats exposed to 2,3,7,8-TCDD and in the plasma of incineration workers exposed to dioxins. HepG2 cells were treated with various concentrations of 2,3,7,8-TCDD (0, 0.25, 0.5, 1, 2.5, 5, 10, 25 nM) for 24 or 48 h. MTT and Comet assays were performed to determine cytotoxicities and genotoxicities to select exposure concentrations for the proteomic analysis of proteins secreted by 2,3,7,8-TCDD-treated cells. In the proteomic analysis, dose- and time-dependent toxicological biomarkers were evaluated using two pI ranges (4-7 and 6-9) using a large gel 2-DE system. Fifteen secreted proteins were identified by a nano-LC-ESI-MS/MS and nano-ESI on a Q-TOF2 MS and the identities of eight secreted proteins including glyoxalase 1 (GLO 1), homogentisate dioxygenase (HGD), peroxiredoxin 1 (PRX 1), proteasome subunit beta type (PSMB) 5 and 6, UDP-glucose 6-dehydrogenase (UDP-GlcDH), hydroxyacyl-coenzyme A dehydrogenase (HADH) and serotransferrin (STF) were confirmed by western blotting. Of these, PSMB 5 and PRX 1 were also found in the plasma of rats exposed to 2,3,7,8-TCDD, whereas GLO 1, HGD, PSMB 6 and PRX 1 were found in the plasma of incineration workers exposed to dioxins. Copyright © 2016. Published by Elsevier B.V.

  11. Peroxiredoxin 2: a potential biomarker for early diagnosis of Hepatitis B Virus related liver fibrosis identified by proteomic analysis of the plasma

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    Wang Haijian

    2010-10-01

    Full Text Available Abstract Background Liver fibrosis is a middle stage in the course of chronic Hepatitis B virus (HBV infection, which will develop into cirrhosis and eventually hepatocellular carcinoma (HCC if not treated at the early stage. Considering the limitations and patients' reluctance to undergo liver biopsy, a reliable, noninvasive diagnostic system to predict and assess treatment and prognosis of liver fibrosis is needed. The aim of this study was to identify biomarkers for early diagnosis of HBV related liver fibrosis. Method Plasma samples from 7 healthy volunteers and 27 HBV infected patients with different stages of fibrosis were selected for 2-DIGE proteomic screening. One-way ANOVA analysis was used to assess differences in protein expression among all groups. The alteration was further confirmed by western blotting. Plasma levels of 25 serological variables in 42 healthy volunteers and 68 patients were measured to establish a decision tree for the detection of various stages fibrosis. Result The up-regulated proteins along with fibrosis progress included fibrinogen, collagen, macroglobulin, hemopexin, antitrypsin, prealbumin and thioredoxin peroxidase. The down-regulated proteins included haptoglobin, serotransferrin, CD5 antigen like protein, clusterin, apolipoprotein and leucine-rich alpha-2-glycoprotein. For the discrimination of milder stage fibrosis, the area under curve for Prx II was the highest. Four variables (PT, Pre, HA and Prx II were selected from the 25 variables to construct the decision tree. In a training group, the correct prediction percentage for normal control, milder fibrosis, significant fibrosis and early cirrhosis was 100%, 88.9%, 95.2% and 100%, respectively, with an overall correct percent of 95.9%. Conclusion This study showed that 2-D DIGE-based proteomic analysis of the plasma was helpful in screening for new plasma biomarkers for liver disease. The significant up-expression of Prx II could be used in the early

  12. Expression profile of desiccation tolerance factors in intertidal seaweed species during the tidal cycle.

    Science.gov (United States)

    Fierro, Camila; López-Cristoffanini, Camilo; Meynard, Andrés; Lovazzano, Carlos; Castañeda, Francisco; Guajardo, Eduardo; Contreras-Porcia, Loretto

    2017-06-01

    The transcriptional modulation of desiccation tolerance factors in P. orbicularis explains its successful recuperation after water deficit. Differential responses to air exposure clarify seaweed distribution along intertidal rocky zones. Desiccation-tolerant seaweed species, such as Pyropia orbicularis, can tolerate near 96% water loss during air exposure. To understand the phenotypic plasticity of P. orbicularis to desiccation, several tolerance factors were assessed by RT-qPCR, Western-blot analysis, and enzymatic assays during the natural desiccation-rehydration cycle. Comparative enzymatic analyses were used to evidence differential responses between P. orbicularis and desiccation-sensitive species. The results showed that during desiccation, the relative mRNA levels of genes associated with basal metabolism [trehalose phosphate synthase (tps) and pyruvate dehydrogenase (pdh)] were overexpressed in P. orbicularis. Transcript levels related to antioxidant metabolism [peroxiredoxin (prx); thioredoxin (trx); catalase (cat); lipoxygenase (lox); ferredoxin (fnr); glutathione S-transferase (gst)], cellular detoxification [ABC transporter (abc) and ubiquitin (ubq)], and signal transduction [calmodulin (cam)] increased approximately 15- to 20-fold, with the majority returning to basal levels during the final hours of rehydration. In contrast, actin (act) and transcription factor 1 (tf1) transcripts were down-regulated. ABC transporter protein levels increased in P. orbicularis during desiccation, whereas PRX transcripts decreased. The antioxidant enzymes showed higher specific activity in P. orbicularis under desiccation, and sensitive species exhibited enzymatic inactivation and scarce ABC and PRX protein detection following prolonged desiccation. In conclusion, the reported findings contribute towards understanding the ecological distribution of intertidal seaweeds at the molecular and functional levels.

  13. Identification of a novel and unique transcription factor in the intraerythrocytic stage of Plasmodium falciparum.

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    Kanako Komaki-Yasuda

    Full Text Available The mechanisms of stage-specific gene regulation in the malaria parasite Plasmodium falciparum are largely unclear, with only a small number of specific regulatory transcription factors (AP2 family having been identified. In particular, the transcription factors that function in the intraerythrocytic stage remain to be elucidated. Previously, as a model case for stage-specific transcription in the P. falciparum intraerythrocytic stage, we analyzed the transcriptional regulation of pf1-cys-prx, a trophozoite/schizont-specific gene, and suggested that some nuclear factors bind specifically to the cis-element of pf1-cys-prx and enhance transcription. In the present study, we purified nuclear factors from parasite nuclear extract by 5 steps of chromatography, and identified a factor termed PREBP. PREBP is not included in the AP2 family, and is a novel protein with four K-homology (KH domains. The KH domain is known to be found in RNA-binding or single-stranded DNA-binding proteins. PREBP is well conserved in Plasmodium species and partially conserved in phylum Apicomplexa. To evaluate the effects of PREBP overexpression, we used a transient overexpression and luciferase assay combined approach. Overexpression of PREBP markedly enhanced luciferase expression under the control of the pf1-cys-prx cis-element. These results provide the first evidence of a novel transcription factor that activates the gene expression in the malaria parasite intraerythrocytic stage. These findings enhance our understanding of the evolution of specific transcription machinery in Plasmodium and other eukaryotes.

  14. NADPH-thioredoxin reductase C mediates the response to oxidative stress and thermotolerance in the cyanobacterium Anabaena sp. PCC7120.

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    ANA MARÍA SÁNCHEZ-RIEGO

    2016-08-01

    Full Text Available NTRC (NADPH-thioredoxin reductase C is a bimodular enzyme composed of an NADPH-thioredoxin reductase and a thioredoxin domain extension in the same protein. In plants, NTRC has been described to be involved in the protection of the chloroplast against oxidative stress damage through reduction of the 2-Cys peroxiredoxin (2-Cys Prx as well as through other functions related to redox enzyme regulation. In cyanobacteria, the Anabaena NTRC has been characterized in vitro, however nothing was known about its in vivo function. In order to study that, we have generated the first knockout mutant strain (∆ntrC, apart from the previously described in Arabidopsis. Detailed characterization of this strain reveals a differential sensitivity to oxidative stress treatments with respect to the wild-type Anabaena strain, including a higher level of ROS (reactive oxygen species in normal growth conditions. In the mutant strain, different oxidative stress treatments such as hydrogen peroxide, methyl-viologen or high light irradiance provoke an increase in the expression of genes related to ROS detoxification, including AnNTRC and peroxiredoxin genes, with a concomitant increase in the amount of AnNTRC and 2-Cys Prx. Moreover, the role of AnNTRC in the antioxidant response is confirmed by the observation of a pronounced overoxidation of the 2-Cys Prx and a time-delay recovery of the reduced form of this protein upon oxidative stress treatments. Our results suggest the participation of this enzyme in the peroxide detoxification in Anabaena. In addition, we describe the role of Anabaena NTRC in thermotolerance, by the appearance of high molecular mass AnNTRC complexes, showing that the mutant strain is more sensitive to high temperature treatments.

  15. Non-cognitive behavior associated with development of Alzheimer pathology in APPswePS1dE9 mice and an effect of long-term paroxetine treatment

    DEFF Research Database (Denmark)

    Bouzinova, Elena; Olesen, Louise Ørum; Wiborg, Ove

    to characterize non-cognitive behavioral changes associated with development of pathology and differentiated from normal aging. We have used open field and elevated plus maze tests to capture the behavioral pattern of Tg and Wt mice and performed these tests at 9, 12, 15, and 18 months of age. The principal......-cognitive behavioural phenotype become apparent beyond 15 months of age. We observed decline in locomotion, in exploration and risk assessment behaviour specific for the AD pathology, which were delayed by treatment with prx. Furthermore, the analysis of locomotion at 18 months of age is sufficient to describe the AD...... associated non-cognitive phenotype....

  16. Análisis de la variabilidad genética de la colección colombiana de musáceas usando marcadores isoenzimáticos Analysis of the genetic variability of colombian collection of Musaceae using isozyme markers

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    Martha C Giraldo

    2011-04-01

    Full Text Available La Colección Colombiana de Musáceas (CCM es la única a nivel mundial que representa un alto valor por ser la que posee introducciones andinas de altura (> 1500 m.s.n.m.. La caracterización de este germoplasma puede generar valor agregado para su utilización en procesos de selección clonal y para el mejoramiento genético de la especie, mediante el uso de materiales diploides con características transmisibles de importancia. Por esta razón, 33 clones de la CCM conservadas in vitro, fueron evaluadas bioquímicamente mediante 10 enzimas, de las cuales cuatro fueron polimórficas: glutamato oxaloacetil transaminasa (GOT, ab-esterasa (ab-EST, peroxidasa (PRX y diaforasa (DIAP. La enzima GOT fue la más discriminante entre grupos genómicos particulares. PRX, DIAP y ab-EST permitieron evaluar la variabilidad al interior de cada grupo. El estudio facilita el entendimiento de la estructura genética de los genotipos de plátano y banano cultivados en Colombia.The Colombian Collection of Musaceae (CCM represents a great value to the world agriculture for being the only one with high Andean germplasm. The characterization of this germplasm can generate added value to use in processes of clone selection and breeding of the species by using diploid materials with desirable traits to be transferred and thus help alleviate food problems in poor countries. For this reason the CCM 33 clones conserved in vitro, were assessed biochemically using 10 enzymes of which four were polimorfics: oxaloacetil transaminasa glutamate (GOT, ab-esterase (ab-EST, peroxidase (PRX and diaphorase (DIAP. The GOT enzyme was the most discriminating among individual genomic groups. PRX, ab-EST and DIAP allowed us to evaluate the variability within each group. The study provided a better understanding of the genetic structure of the genotypes of plantain and banana grown in Colombia.

  17. Caracterización por isoenzimas de accesiones de capsicum pertenecientes a la colección amazónica colombiana

    OpenAIRE

    Quintero Barrera, Lorena; García, Marisol Cudris; Giraldo, Martha Cecilia; Melgarejo, Luz Marina

    2007-01-01

    Doscientas sesenta y una accesiones del género Capsicum del banco de germoplasma del Instituto Amazónico de Investigaciones Científicas (Sinchi) se evaluaron a través de cinco sistemas enzimáticos polimórficos: esterasa (EST), peroxidasa (PRX), 6-fosfogluconato deshidrogenasa (6-PGDH), aspartato amino transferasa (GOT) y enzima málica (ME). Se utilizó un análisis de agrupamiento (Upgma) con el fin de determinar la variabilidad genética. Se observó un agrupamiento de las especies C. baccatum y...

  18. Caracterización por isoenzimas de accesiones de Capsicum pertenecientes a la colección amazónica Colombiana Isozyme characterization of Capsicum accessions from the Amazonian Colombian collection

    OpenAIRE

    Melgarejo Luz Marina; Giraldo Martha Cecilia; Quintero Barrera Lorena; García Marisol Cudris

    2005-01-01

    Doscientas sesenta y una accesiones del género Capsicum del banco de germoplasma del Instituto Amazónico de Investigaciones Científicas (Sinchi) se evaluaron a través de cinco sistemas enzimáticos polimórficos: esterasa (EST), peroxidasa (PRX), 6-fosfogluconato deshidrogenasa (6-PGDH), aspartato amino transferasa (GOT) y enzima málica (ME). Se utilizó un análisis de agrupamiento (Upgma) con el fin de determinar la variabilidad genética. Se observó un agrupamiento de las especies C. baccatum y...

  19. cDNA, amino acid carbohydrate sequence of barley seed-specific peroxidase BP 1

    DEFF Research Database (Denmark)

    Johansson, A.; Rasmussen, Søren Kjærsgård; Harthill, J.E.

    1992-01-01

    The major peroxidase of barley seed BP 1 was characterized. Previous studies showed a low carbohydrate content, low specific activity and tissue-specific expression, and suggested that this basic peroxidase could be particularly useful in the elucidation of the structure-function relationship...... plant modified-type structure, Man-alpha-1-6(Xyl-beta-1-2)Man-beta-1-4GlcNAc-beta-1-4(Fuc-alpha-1-3)GlcNAc. The BP 1 gene was RFLP-mapped on barley chromosome 3, and we propose Prx5 as the name for this new peroxidase locus....

  20. Lifelong training preserves some redox-regulated adaptive responses after an acute exercise stimulus in aged human skeletal muscle.

    Science.gov (United States)

    Cobley, J N; Sakellariou, G K; Owens, D J; Murray, S; Waldron, S; Gregson, W; Fraser, W D; Burniston, J G; Iwanejko, L A; McArdle, A; Morton, J P; Jackson, M J; Close, G L

    2014-05-01

    Several redox-regulated responses to an acute exercise bout fail in aged animal skeletal muscle, including the ability to upregulate the expression of antioxidant defense enzymes and heat shock proteins (HSPs). These findings are generally derived from studies on sedentary rodent models and thus may be related to reduced physical activity and/or intraspecies differences as opposed to aging per se. This study, therefore, aimed to determine the influence of age and training status on the expression of HSPs, antioxidant enzymes, and NO synthase isoenzymes in quiescent and exercised human skeletal muscle. Muscle biopsy samples were obtained from the vastus lateralis before and 3 days after an acute high-intensity-interval exercise bout in young trained, young untrained, old trained, and old untrained subjects. Levels of HSP72, PRX5, and eNOS were significantly higher in quiescent muscle of older compared with younger subjects, irrespective of training status. 3-NT levels were elevated in muscles of the old untrained but not the old trained state, suggesting that lifelong training may reduce age-related macromolecule damage. SOD1, CAT, and HSP27 levels were not significantly different between groups. HSP27 content was upregulated in all groups studied postexercise. HSP72 content was upregulated to a greater extent in muscle of trained compared with untrained subjects postexercise, irrespective of age. In contrast to every other group, old untrained subjects failed to upregulate CAT postexercise. Aging was associated with a failure to upregulate SOD2 and a downregulation of PRX5 in muscle postexercise, irrespective of training status. In conclusion, lifelong training is unable to fully prevent the progression toward a more stressed muscular state as evidenced by increased HSP72, PRX5, and eNOS protein levels in quiescent muscle. Moreover, lifelong training preserves some (e.g., CAT) but not all (e.g., SOD2, HSP72, PRX5) of the adaptive redox-regulated responses after an

  1. Disruption of reducing pathways is not essential for efficient disulfide bond formation in the cytoplasm of E. coli

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    Hatahet Feras

    2010-09-01

    Full Text Available Abstract Background The formation of native disulfide bonds is a complex and essential post-translational modification for many proteins. The large scale production of these proteins can be difficult and depends on targeting the protein to a compartment in which disulfide bond formation naturally occurs, usually the endoplasmic reticulum of eukaryotes or the periplasm of prokaryotes. It is currently thought to be impossible to produce large amounts of disulfide bond containing protein in the cytoplasm of wild-type bacteria such as E. coli due to the presence of multiple pathways for their reduction. Results Here we show that the introduction of Erv1p, a sulfhydryl oxidase and FAD-dependent catalyst of disulfide bond formation found in the inter membrane space of mitochondria, allows the efficient formation of native disulfide bonds in heterologously expressed proteins in the cytoplasm of E. coli even without the disruption of genes involved in disulfide bond reduction, for example trxB and/or gor. Indeed yields of active disulfide bonded proteins were higher in BL21 (DE3 pLysSRARE, an E. coli strain with the reducing pathways intact, than in the commercial Δgor ΔtrxB strain rosetta-gami upon co-expression of Erv1p. Conclusions Our results refute the current paradigm in the field that disruption of at least one of the reducing pathways is essential for the efficient production of disulfide bond containing proteins in the cytoplasm of E. coli and open up new possibilities for the use of E. coli as a microbial cell factory.

  2. Quickly-released peroxidase of moss in defense against fungal invaders.

    Science.gov (United States)

    Lehtonen, Mikko T; Akita, Motomu; Kalkkinen, Nisse; Ahola-Iivarinen, Elina; Rönnholm, Gunilla; Somervuo, Panu; Thelander, Mattias; Valkonen, Jari P T

    2009-01-01

    Mosses (Bryophyta) are nonvascular plants that constitute a large part of the photosynthesizing biomass and carbon storage on Earth. Little is known about how this important portion of flora maintains its health status. This study assessed whether the moss, Physcomitrella patens, responds to treatment with chitosan, a fungal cell wall-derived compound inducing defense against fungal pathogens in vascular plants. Application of chitosan to liquid culture of P. patens caused a rapid increase in peroxidase activity in the medium. For identification of the peroxidase(s), matrix-assisted laser desorption/ionization-time-of-flight (MALDI-TOF)/MS, other methods and the whole-genome sequence of P. patens were utilized. Peroxidase gene knock-out mutants were made and inoculated with fungi. The peroxidase activity resulted from a single secreted class III peroxidase (Prx34) which belonged to a P. patens specific phylogenetic cluster in analysis of the 45 putative class III peroxidases of P. patens and those of Arabidopsis and rice. Saprophytic and pathogenic fungi isolated from another moss killed the Prx34 knockout mutants but did not damage wild-type P. patens. The data point out the first specific host factor that is pivotal for pathogen defense in a nonvascular plant. Furthermore, results provide conclusive evidence that class III peroxidases in plants are needed in defense against hostile invasion by fungi.

  3. Induction of antioxidant genes by sulforaphane and klotho in human aortic smooth muscle cells.

    Science.gov (United States)

    Rizzo, Benedetta; Maltese, Giuseppe; Paraskevi, Maria Psefteli; Hrelia, Silvana; Mann, Giovanni; Siow, Richard

    2014-10-01

    Vascular smooth muscle cell (SMC) dysfunction due to enhanced oxidative stress contributes to age-related cardiovascular diseases such as atherosclerosis and calcification. Klotho, a protein with multiple pleiotropic effects associated with anti-ageing, can extend lifespan when overexpressed while its deficiencies result in rapid aging. It exists in membrane and secreted forms with distinct pleiotropic functions, with the secreted form regulating ion channels, suppressing growth factor signaling and oxidative stress while the transmembrane protein forms a co-receptor for FGF23, although the mechanisms involved in its actions remain to be fully elucidated. Sulforaphane (SFN) is an isothiocyanate present in cruciferous vegetables that can induce antioxidant defence enzymes such as heme oxygenase-1 (HO-1) and peroxiredoxin-1 (Prx-1). The present study investigates whether SFN or klotho increases antioxidant defences in cultured human aortic SMC. Cells were treated (0-24h) with either SFN (0-5µM) or klotho (0-1nM) and HO-1, Prx-1 expression determined by western blot analyses and glutathione (GSH) levels measured using the o-phthalaldehyde fluorescence assay. SFN significantly (pMarco Polo' Program, University of Bologna. Copyright © 2014. Published by Elsevier Inc.

  4. Effect of the Algaecide Palmitoleic Acid on the Immune Function of the Bay Scallop Argopecten irradians

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    Cheng Chi

    2016-05-01

    Full Text Available Palmitoleic acid (PA, an algicidal compound, is used against the toxin producing dinofagelate Alexandrium tamarense, however, its impact on the edible bay scallop (Argopecten irradians is still unclear. Therefore, we investigated the impacts of effective algicidal concentrations (20, 40, and 80 mg/L of PA on immune responses in A. irradians. Various immune parameters including acid phosphatase (ACP activity, superoxide dismutase (SOD, lysozyme, phagocytic activity, total protein, malondialdehyde (MDA level, and reactive oxygen species (ROS production and the expression of immune-related genes (PrxV, CLT-6, MT, and BD were measured at 3, 6, 12, 24, and 48 h post-exposure (hpe to PA. Lysozyme activity was lower in scallops at 12–48 hpe to 80 mg/L. SOD, ACP activity, ROS production, the total protein, and MDA level was higher at 12 to 48 hpe with different concentrations of PA. Phagocytic activity increased at 6–12 hpe to 40–80 mg/L of PA, but decreased at 24–48 hpe. The expressions of genes PrxV, CLT-6, MT and BD down-regulated at 3 hpe were observed, while differential expressions from 6–48 hpe with different concentrations of PA. The present study demonstrated that immersing A. irradians in PA at effective concentrations could result in differential effects on non-specific immune responses and expressions of immune-related genes.

  5. Calcium and magnesium ions modulate the oligomeric state and function of mitochondrial 2-Cys peroxiredoxins in Leishmania parasites.

    Science.gov (United States)

    Morais, Mariana A B; Giuseppe, Priscila O; Souza, Tatiana A C B; Castro, Helena; Honorato, Rodrigo V; Oliveira, Paulo S L; Netto, Luis E S; Tomas, Ana M; Murakami, Mario T

    2017-04-28

    Leishmania parasites have evolved a number of strategies to cope with the harsh environmental changes during mammalian infection. One of these mechanisms involves the functional gain that allows mitochondrial 2-Cys peroxiredoxins to act as molecular chaperones when forming decamers. This function is critical for parasite infectivity in mammals, and its activation has been considered to be controlled exclusively by the enzyme redox state under physiological conditions. Herein, we have revealed that magnesium and calcium ions play a major role in modulating the ability of these enzymes to act as molecular chaperones, surpassing the redox effect. These ions are directly involved in mitochondrial metabolism and participate in a novel mechanism to stabilize the decameric form of 2-Cys peroxiredoxins in Leishmania mitochondria. Moreover, we have demonstrated that a constitutively dimeric Prx1m mutant impairs the survival of Leishmania under heat stress, supporting the central role of the chaperone function of Prx1m for Leishmania parasites during the transition from insect to mammalian hosts. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  6. Study on production of useful metabolites by development of advanced cell culture techniques using radiation

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Byung Yeoup; Lee, Seung Sik; Bai, Hyounwoo; Singh, Sudhir; Lee, Eun Mi; Hong, Sung Hyun; Park, Chul Hong; Srilatha, B.; Kim, Mi Ja; Lee, Ohchul

    2012-01-15

    The purpose of this project is improvement of investigation, materialization and evaluation techniques on effectiveness for functional natural compounds throughout development of tissue/cell culture techniques for mass production of useful metabolites using radiation. Research scope includes Development of a technique for radiation tissue and cell culture, Database construction for radiation response in plants and radiation effects, Construction of general-purpose national based techniques of cell culture technique using radiation. Main results are as follow: Development of a technique for radiation tissue and cell culture for Erigeron breviscapus (Vant.) Hand. Mazz.; Identification and functional analysis of AtTDX (chaperone and peroxidase activities); Functional analysis of radiation(gamma ray, electron beam, and proton beam) induced chaperon protein activities (AtTDX); Determine the action mechanism of yPrx2; Development of transgenic plant with bas I gene from Arabidopsis; Development of transgenic plant with EoP gene from centipedegrass; Identification of radiation induced multi functional compounds from Aloe; Determination of the effects of radiation on removing undesirable color and physiological activities (Schizandra chinensis baillon, centipedegrass); Determine the action mechanism of transgenic plant with 2-Cys Prx for heat stress resistance; Determination of the effects of centipedegrass extracts on anti-cancer activities; Functional analysis of centipedegrass extracts (anti-virus effects)

  7. Effect of the Algaecide Palmitoleic Acid on the Immune Function of the Bay Scallop Argopecten irradians.

    Science.gov (United States)

    Chi, Cheng; Giri, Sib Sankar; Jun, Jin Woo; Kim, Hyoun Joong; Kim, Sang Guen; Yun, Saekil; Park, Se Chang

    2016-05-10

    Palmitoleic acid (PA), an algicidal compound, is used against the toxin producing dinofagelate Alexandrium tamarense, however, its impact on the edible bay scallop (Argopecten irradians) is still unclear. Therefore, we investigated the impacts of effective algicidal concentrations (20, 40, and 80 mg/L) of PA on immune responses in A. irradians. Various immune parameters including acid phosphatase (ACP) activity, superoxide dismutase (SOD), lysozyme, phagocytic activity, total protein, malondialdehyde (MDA) level, and reactive oxygen species (ROS) production and the expression of immune-related genes (PrxV, CLT-6, MT, and BD) were measured at 3, 6, 12, 24, and 48 h post-exposure (hpe) to PA. Lysozyme activity was lower in scallops at 12-48 hpe to 80 mg/L. SOD, ACP activity, ROS production, the total protein, and MDA level was higher at 12 to 48 hpe with different concentrations of PA. Phagocytic activity increased at 6-12 hpe to 40-80 mg/L of PA, but decreased at 24-48 hpe. The expressions of genes PrxV, CLT-6, MT and BD down-regulated at 3 hpe were observed, while differential expressions from 6-48 hpe with different concentrations of PA. The present study demonstrated that immersing A. irradians in PA at effective concentrations could result in differential effects on non-specific immune responses and expressions of immune-related genes.

  8. Genetic diversity and recruitment of the tropical palm, Euterpe edulis Mart., in a natural population from the Brazilian Atlantic Forest.

    Science.gov (United States)

    Conte, R; Nodari, R O; Vencovsky, R; dos Reis, M Sedrez

    2003-10-01

    The genetic diversity and recruitment of plants of heart-of-palm tree (Euterpe edulis Mart.) were investigated in a natural population located in Southern Brazil. Five categories of plants, from seedlings to adults, were analysed using 16 allozymic loci. The results showed an average population level of genetic diversity (He=0.278) greater than the average of plant species already studied. The recruitment process of E. edulis is related to its genetic characteristics. A significant increase in the heterozygote frequency towards the adult stages was observed at three loci (Pgdh-2, G6pdh-1 and Mdh-1). This suggests the possible action of natural selection in promoting such heterozygote increase. In the same way, a linear increase in allele frequencies was observed at four loci (Prx-3, Prx-4, Pgdh-2 and G6pdh-1), indicating that recruitment is also related to a greater survival of individuals that are carriers of certain alleles. The maintenance of high diversity levels, as well as the increase in the heterozygote frequency, are positive aspects for in situ conservation. Furthermore, an increase in heterozygote frequency is favourable to the management of the species, since the maintenance of a stock of reproductive individuals with high heterozygosity levels favours the maintenance of the population dynamic and structure.

  9. Dkk1 haploinsufficiency requires expression of Bmp2 for bone anabolic activity

    Science.gov (United States)

    Intini, Giuseppe; Nyman, Jeffry S.

    2015-01-01

    Bone fractures remain a serious health burden and prevention and enhanced healing of fractures has been obtained by augmenting either BMP or Wnt signaling. However, whether BMP and Wnt signaling are both required or are self-sufficient for anabolic and fracture healing activities has never been fully elucidated. Mice haploinsufficient for Dkk1 (Dkk1+/−) exhibit a high bone mass phenotype due to an up-regulation of canonical Wnt signaling while mice lacking Bmp2 expression in the limbs (Bmp2c/c;Prx1::cre) succumb to spontaneous fracture and are unable to initiate fracture healing; combined, these mice offer an opportunity to examine the requirement for activated BMP signaling on the anabolic and fracture healing activity of Wnts. When Dkk1+/− mice were crossed with Bmp2c/c;Prx1::cre mice, the offspring bearing both genetic alterations were unable to increase bone mass and heal fractures, indicating that increased canonical Wnt signaling is unable to exploit its activity in absence of Bmp2. Thus, our data suggest that BMP signaling is required for Wnt-mediated anabolic activity and that therapies aimed at preventing fractures and fostering fracture repair may need to target both pathways for maximal efficacy. PMID:25603465

  10. [Intracranial pressure plateau waves in patients with severe traumatic brain injury].

    Science.gov (United States)

    Oshorov, A V; Savin, I A; Goriachev, A S; Popugaev, K A; Polupan, A A; Sychev, A A; Gavrilov, A G; Kravchuk, A D; Zakharova, N E; Danilov, G V; Potapov, A A

    2013-01-01

    The goal of the study was to assess frequency of plato waves, their influence on outcomes and define factors leading to plato waves. Ninety eight patients with severe traumatic brain injury (TBI) were included. Blood pressure (BP), intracranial pressure (ICP), cerebral perfusion pressure (CPP) and pressure reactivity index (Prx) were registered. Age was 34 +/- 13.6. There were 73 male and 25 female. Glasgow Coma Scale (GCS) was 6 +/- 1.4. Plato waves developed in 24 patients (group 1), 74 patients (group 2) did not have plato waves. Median of plato waves in the 1st group was 7[3.5; 7]. They developed on 3rd [2;4.5] day. Maximum level of ICP during plato waves was 47.5 [40;53] mmHg, its duration was 8.5 [7;27] minutes. In the group 1 Prx was significantly lower during first day, than in the group 2. Duration of ICP monitoring was longer in the group I due to presence of plato waves in these patients. CPP did not differ in groups, because CPP was strictly controlled. Patients of the group I had preserved autoregulation and less severe trauma (predominance of closed trauma and Marshall I, II type of brain damage). Plato waves did not predict bad outcomes.

  11. DCA1 Acts as a Transcriptional Co-activator of DST and Contributes to Drought and Salt Tolerance in Rice.

    Directory of Open Access Journals (Sweden)

    Long-Gang Cui

    2015-10-01

    Full Text Available Natural disasters, including drought and salt stress, seriously threaten food security. In previous work we cloned a key zinc finger transcription factor gene, Drought and Salt Tolerance (DST, a negative regulator of drought and salt tolerance that controls stomatal aperture in rice. However, the exact mechanism by which DST regulates the expression of target genes remains unknown. In the present study, we demonstrated that DST Co-activator 1 (DCA1, a previously unknown CHY zinc finger protein, acts as an interacting co-activator of DST. DST was found to physically interact with itself and to form a heterologous tetramer with DCA1. This transcriptional complex appears to regulate the expression of peroxidase 24 precursor (Prx 24, a gene encoding an H2O2 scavenger that is more highly expressed in guard cells. Downregulation of DCA1 significantly enhanced drought and salt tolerance in rice, and overexpression of DCA1 increased sensitivity to stress treatment. These phenotypes were mainly influenced by DCA1 and negatively regulated stomatal closure through the direct modulation of genes associated with H2O2 homeostasis. Our findings establish a framework for plant drought and salt stress tolerance through the DCA1-DST-Prx24 pathway. Moreover, due to the evolutionary and functional conservation of DCA1 and DST in plants, engineering of this pathway has the potential to improve tolerance to abiotic stress in other important crop species.

  12. Identification of 2-Cys Peroxiredoxin (BmTPx-2 as Antioxidant Active Molecule from Babesia microti

    Directory of Open Access Journals (Sweden)

    Xunan Hai

    2017-10-01

    Full Text Available Peroxiredoxins (Prxs are a family of antioxidant enzymes that reduce peroxides in the presence of thioredoxin, thioredoxin reductase, and nicotinamide adenine dinucleotide phosphate (NADPH to resist oxidative stress. In this study, we identified and isolated a 2-Cys Prx designated as ‘BmTPx-2’ from Babesia microti, with a full-length cDNA of 826 bp and an open reading frame of 756 bp, which encodes a 251-amino acid protein. BLAST analysis demonstrated that BmTPx-2 shows the typical features of members of the 2-Cys Prx family, which includes harboring two conserved VCP motifs with Cys101 and Cys221 conserved cysteine residues. Recombinant BmTPx-2 was expressed in Escherichia coli and analyzed by western blot. The antioxidant activity of BmTPx-2 was demonstrated using a mixed-function oxidation system and oxidation of NADPH. Furthermore, BmTPx-2 mRNA expression level in parasites at the erythrocytes and tick stages were analyzed by real-time fluorescence quantitative PCR. Peak BmTPx-2 mRNA transcription was detected 8 days after infection at the erythrocyte stage, but not at the tick stage. Taken together, this study characterized BmTPx-2 from B. microti as an antioxidant molecule that was specifically transcribed at the erythrocyte stage.

  13. Structural, evolutionary and functional analysis of the class III peroxidase gene family in Chinese pear (Pyrus bretschneideri

    Directory of Open Access Journals (Sweden)

    Yun Peng Cao

    2016-12-01

    Full Text Available Peroxidases (PRXs are widely existed in various organisms and could be divided into different types according to their structures and functions. Specifically, the Class III Peroxidase, a plant-specific multi-gene family, involves in many physiological processes, such as the metabolism of auxin, the extension and thickening of cell wall, as well as the formation of lignin. By searching the pear genome database, 94 non-redundant PRXs from Pyrus bretschneideri (PbPRXs were identified. Subsequently, analysis of phylogenetic relationships, gene structures, conserved motifs, and microsynteny was performed. These PbPRXs were unevenly distributed among 17 chromosomes of pear. In addition, 26 segmental duplication events but only one tandem duplication were occurred in these PbPRXs, implying segmental duplication was the main contributor to the expansion of the PbPRX family. By the Ka/Ks analysis, 26 out of 27 duplicated PbPRXs has experienced purifying selection. Twenty motifs were identified in PbPRXs based on the MEME analysis, eleven of which were enriched in pear. A total of 41 expressed genes were identified from ESTs of pear fruit. According to qRT-PCR, the expression trends of five PbPRXs in subgroup C were consistent with the change of lignin content during pear fruit development. So we inferred that the five PbPRXs were candidate genes involved in the lignin synthesis pathway. These results provided useful information for further researches of PRX genes in pear.

  14. Giant anisotropic nonlinear optical response in transition metal monopnictide Weyl semimetals

    CERN Document Server

    Wu, Liang; Morimoto, Takahiro; Nair, Nityan L; Thewalt, Eric; Little, Arielle; Analytis, James G; Moore, Joel E; Orenstein, J

    2016-01-01

    Although Weyl fermions have proven elusive in high-energy physics, their existence as emergent quasiparticles was recently predicted in certain crystalline solids in which either inversion or time-reversal symmetry is broken\\cite{WanPRB2011,BurkovPRL2011, WengPRX2015,HuangNatComm2015}. The subsequent search for Weyl fermions in condensed matter soon led to their detection\\cite{XuScience2015, LvPRX2015, YangNatPhys2015} in transition metal monopnictides (TMMPs) such as TaAs, a class of noncentrosymmetric materials that heretofore received only limited attention. Now that the Weyl semimetal state in TMMPs is confirmed, the question arises as to whether these materials will exhibit novel, enhanced, or technologically applicable electronic properties. The TMMPs are polar metals, a rare subset of inversion-breaking crystals that would allow spontaneous polarization, were it not screened by conduction electrons\\cite{anderson1965symmetry,shi2013ferroelectric,kim2016polar}. Despite the absence of spontaneous polariza...

  15. Quantitative high-throughput screen identifies inhibitors of the Schistosoma mansoni redox cascade.

    Directory of Open Access Journals (Sweden)

    Anton Simeonov

    2008-01-01

    Full Text Available Schistosomiasis is a tropical disease associated with high morbidity and mortality, currently affecting over 200 million people worldwide. Praziquantel is the only drug used to treat the disease, and with its increased use the probability of developing drug resistance has grown significantly. The Schistosoma parasites can survive for up to decades in the human host due in part to a unique set of antioxidant enzymes that continuously degrade the reactive oxygen species produced by the host's innate immune response. Two principal components of this defense system have been recently identified in S. mansoni as thioredoxin/glutathione reductase (TGR and peroxiredoxin (Prx and as such these enzymes present attractive new targets for anti-schistosomiasis drug development. Inhibition of TGR/Prx activity was screened in a dual-enzyme format with reducing equivalents being transferred from NADPH to glutathione via a TGR-catalyzed reaction and then to hydrogen peroxide via a Prx-catalyzed step. A fully automated quantitative high-throughput (qHTS experiment was performed against a collection of 71,028 compounds tested as 7- to 15-point concentration series at 5 microL reaction volume in 1536-well plate format. In order to generate a robust data set and to minimize the effect of compound autofluorescence, apparent reaction rates derived from a kinetic read were utilized instead of end-point measurements. Actives identified from the screen, along with previously untested analogues, were subjected to confirmatory experiments using the screening assay and subsequently against the individual targets in secondary assays. Several novel active series were identified which inhibited TGR at a range of potencies, with IC(50s ranging from micromolar to the assay response limit ( approximately 25 nM. This is, to our knowledge, the first report of a large-scale HTS to identify lead compounds for a helminthic disease, and provides a paradigm that can be used to jump

  16. Modulation of the Acetone/Butanol Ratio during Fermentation of Corn Stover-Derived Hydrolysate by Clostridium beijerinckii Strain NCIMB 8052.

    Science.gov (United States)

    Liu, Zi-Yong; Yao, Xiu-Qing; Zhang, Quan; Liu, Zhen; Wang, Ze-Jie; Zhang, Yong-Yu; Li, Fu-Li

    2017-04-01

    Producing biobutanol from lignocellulosic biomass has shown promise to ultimately reduce greenhouse gases and alleviate the global energy crisis. However, because of the recalcitrance of a lignocellulosic biomass, a pretreatment of the substrate is needed which in many cases releases soluble lignin compounds (SLCs), which inhibit growth of butanol-producing clostridia. In this study, we found that SLCs changed the acetone/butanol ratio (A/B ratio) during butanol fermentation. The typical A/B molar ratio during Clostridium beijerinckii NCIMB 8052 batch fermentation with glucose as the carbon source is about 0.5. In the present study, the A/B molar ratio during batch fermentation with a lignocellulosic hydrolysate as the carbon source was 0.95 at the end of fermentation. Structural and redox potential changes of the SLCs were characterized before and after fermentation by using gas chromatography/mass spectrometry and electrochemical analyses, which indicated that some exogenous SLCs were involved in distributing electron flow to C. beijerinckii , leading to modulation of the redox balance. This was further demonstrated by the NADH/NAD + ratio and trxB gene expression profile assays at the onset of solventogenic growth. As a result, the A/B ratio of end products changed significantly during C. beijerinckii fermentation using corn stover-derived hydrolysate as the carbon source compared to glucose as the carbon source. These results revealed that SLCs not only inhibited cell growth but also modulated the A/B ratio during C. beijerinckii butanol fermentation. IMPORTANCE Bioconversion of lignocellulosic feedstocks to butanol involves pretreatment, during which hundreds of soluble lignin compounds (SLCs) form. Most of these SLCs inhibit growth of solvent-producing clostridia. However, the mechanism by which these compounds modulate electron flow in clostridia remains elusive. In this study, the results revealed that SLCs changed redox balance by producing oxidative

  17. Sequence analysis and characterization of a 40-kilodalton Borrelia hermsii glycerophosphodiester phosphodiesterase homolog.

    Science.gov (United States)

    Shang, E S; Skare, J T; Erdjument-Bromage, H; Blanco, D R; Tempst, P; Miller, J N; Lovett, M A

    1997-04-01

    , including a glycerol-3-phosphate transporter (GlpT), a glycerol-3-phosphate dehydrogenase (GlpD), and a thioredoxin reductase (TrxB).

  18. Upper limit for the effect of elastic bending stress on the saturation magnetization of La0.8Sr0.2MnO3

    KAUST Repository

    Wang, Q.

    2018-01-31

    Using polarized neutron reflectometry, we measured the influence of elastic bending stress on the magnetization depth profile of a La0.8Sr0.2MnO3 (LSMO) epitaxial film grown on a SrTiO3 substrate. The elastic bending strain of +/- 0.03% has no obvious effect on the magnetization depth profile at saturation. This result is in stark contrast to that of (La1-xPrx)(1-y),Ca-y,MnO3 (LPCMO) films for which strain of +/- 0.01% produced dramatic changes in the magnetization profile and Curie temperature. We attribute the difference between the influence of strain on the saturation magnetization in LSMO (weak or none) and LPCMO (strong) to a difference in the ability of LSMO (weak or none) and LPCMO (strong) to phase separate. Our observation provides an upper limit of tuning LSMO saturation magnetization via elastic strain effect.

  19. Physical Review: a family of journals

    Science.gov (United States)

    Sprouse, Gene

    2013-03-01

    The expansion of research in physics in the last 100 years has been reflected in the expansion of the Physical Review(PR). Reviews of Modern Physics was the first ``new'' journal, starting in 1929. Physical Review Letters commenced in 1958, and was the first ``letters'' type of journal for important new results in all fields. By 1970 the Physical Review itself had grown so large that it was necessary to separate it by field into manageable volumes: PRA, PRB, PRC and PRD, and subsequently PRE, which was split off from PRA. More recently, two Special Topics journals for accelerator physics and physics education were pioneers of the open access business model, and the newest member of the family, Physical Review X, continues this trend. PRX is broad scope and very selective, setting it well above many of the new open access journals with a review standard of ``not incorrect.'' Some possible future directions for the Physical Review journals will be discussed.

  20. Cadmium-induced changes in antioxidative systems and differentiation in roots of contrasted Medicago truncatula lines.

    Science.gov (United States)

    Rahoui, Sondès; Martinez, Yves; Sakouhi, Lamia; Ben, Cécile; Rickauer, Martina; El Ferjani, Ezzeddine; Gentzbittel, Laurent; Chaoui, Abdelilah

    2017-01-01

    Defense pathways and stress responses induced under Cd stress were illustrated in roots of hydroponically grown Medicago truncatula seedlings. Actually, the ascorbate-glutathione and antioxidative system, secondary metabolism events including peroxidases, phenolic compounds, and lignification launching, and developmental modifications were described. Cd (100 μM) initially increased reactive oxygen species, enhanced antioxidative (total SOD, CAT, and PRX) and ascorbate-glutathione-related metabolism enzymes (APX and MDAR), except in A17 and TN1.11. In agreement with peroxidase enhancement, physiological measurement and in situ observation illustrated soluble phenolic compound accumulation under Cd treatment. However, lignification was restricted to recently created protoxylem elements established in the root tip area, usually constituting the elongation zone. Cell death was increased. In the absence of necrotic reactions, developmental changes including lignin deposition, increase in cellulose and pectin contents, intercellular meatus, and condensed and deformed hairs were noticed in Cd-treated roots.

  1. Infection propagator approach to compute epidemic thresholds on temporal networks: impact of immunity and of limited temporal resolution

    CERN Document Server

    Valdano, Eugenio; Colizza, Vittoria

    2015-01-01

    The epidemic threshold of a spreading process indicates the condition for the occurrence of the wide spreading regime, thus representing a predictor of the network vulnerability to the epidemic. Such threshold depends on the natural history of the disease and on the pattern of contacts of the network with its time variation. Based on the theoretical framework introduced in (Valdano et al. PRX 2015) for a susceptible-infectious-susceptible model, we formulate here an infection propagator approach to compute the epidemic threshold accounting for more realistic effects regarding a varying force of infection per contact, the presence of immunity, and a limited time resolution of the temporal network. We apply the approach to two temporal network models and an empirical dataset of school contacts. We find that permanent or temporary immunity do not affect the estimation of the epidemic threshold through the infection propagator approach. Comparisons with numerical results show the good agreement of the analytical ...

  2. Post deposition annealing of epitaxial Ce(1-x)Pr(x)O(2-δ) films grown on Si(111).

    Science.gov (United States)

    Wilkens, H; Spiess, W; Zoellner, M H; Niu, G; Schroeder, T; Wollschläger, J

    2015-04-21

    In this work the structural and morphological changes of Ce1-xPrxO2-δ (x = 0.20, 0.35 and 0.75) films grown on Si(111) due to post deposition annealing are investigated by low energy electron diffraction combined with a spot profile analysis. The surface of the oxide films exhibit mosaics with large terraces separated by monoatomic steps. It is shown that the Ce/Pr ratio and post deposition annealing temperature can be used to tune the mosaic spread, terrace size and step height of the grains. The morphological changes are accompanied by a phase transition from a fluorite type lattice to a bixbyite structure. Furthermore, at high PDA temperatures a silicate formation via a polycrystalline intermediate state is observed.

  3. Ethylene-Induced Vinblastine Accumulation Is Related to Activated Expression of Downstream TIA Pathway Genes in Catharanthus roseus.

    Science.gov (United States)

    Wang, Xi; Pan, Ya-Jie; Chang, Bo-Wen; Hu, Yan-Bo; Guo, Xiao-Rui; Tang, Zhong-Hua

    2016-01-01

    We selected different concentrations of ethephon, to stress C. roseus. We used qRT-PCR and HPLC followed by PCA to obtain comprehensive profiling of the vinblastine biosynthesis in response to ethephon. Based on our findings, the results showed that the high concentration of ethephon had a positive effect at both transcriptional and metabolite level. Meanwhile, there was a remarkable decrease of hydrogen peroxide content and a promoted peroxidase activity in leaves. The loading plot combination with correlation analysis suggested that CrPrx1 could be regarded as a positive regulator and interacts with ethylene response factor (ERF) to play a key role in vinblastine content and peroxidase (POD) activity. This study provides the foundation for a better understanding of the regulation and accumulation of vinblastine in response to ethephon.

  4. Ionic/Electronic Conductivity, Thermal/Chemical Expansion and Oxygen Permeation in Pr and Gd Co-Doped Ceria PrxGd0.1Ce0.9-xO1.95

    DEFF Research Database (Denmark)

    Cheng, Shiyang; Chatzichristodoulou, Christodoulos; Søgaard, Martin

    2017-01-01

    Pr. A series of compositions of PrxGd0.1Ce0.9-xO1.95-δ (x = 0, 0.02, 0.05, 0.08, 0.15, 0.25, 0.3 and 0.4) was prepared by solid state reaction. X-ray powder diffraction (XPD) indicates that Pr is completely dissolved in the fluorite structure up to 40 at.%. Pronounced nonlinear thermal expansion...... behavior was observed as a function of temperature, due to the simultaneous contributions of both thermal and chemical expansion. The electronic and ionic conductivities were measured as a function of temperature and oxygen partial pressure. Within the range from 10 to 15 at.% Pr, a drastic drop...

  5. Mechanical Behaviour and Fracture Mechanics of Praseodymium Modified Lead Titanate Ceramics Prepared by Solid-State Reaction Route

    Directory of Open Access Journals (Sweden)

    Vishal Singh

    2013-01-01

    Full Text Available The praseodymium modified lead titanate ceramics with composition Pb1-xPrxTi0.96Fe0.02Mo0.02O3 where x = 0.04, 0.06, 0.08, and 0.10 prepared by solid-state reaction technique were subjected to indentation induced hardness testing method. The indentations were induced in the applied load ranging from 0.245 N to 4.90 N. The microhardness varies nonlinearly with load and was best explained by the concept of Newtonian resistance pressure as proposed by Hays and Kendall’s law. Crack propagation, fracture toughness (Kc, brittleness index (Bi, and yield strength (σy were studied to understand the effect of Pr content on various mechanical parameters. The load independent values were found to increase with the increase in praseodymium content.

  6. TAK1 Regulates Cartilage and Joint Development via the MAPK and BMP Signaling Pathways

    Science.gov (United States)

    Gunnell, Lea M; Jonason, Jennifer H; Loiselle, Alayna E; Kohn, Anat; Schwarz, Edward M; Hilton, Matthew J; O'Keefe, Regis J

    2010-01-01

    The importance of canonical transforming growth factor β (TGF-β) and bone morphogenetic protein (BMP) signaling during cartilage and joint development is well established, but the necessity for noncanonical (SMAD-independent) signaling during these processes is largely unknown. TGF-β activated kinase 1 (TAK1) is a MAP3K activated by TGF-β, BMP, and other mitogen-activated protein kinase (MAPK) signaling components. We set out to define the potential role for noncanonical, TAK1-mediated signaling in cartilage and joint development via deletion of Tak1 in chondrocytes (Col2Cre;Tak1f/f) and the developing limb mesenchyme (Prx1Cre;Tak1f/f). Deletion of Tak1 in chondrocytes resulted in novel embryonic developmental cartilage defects including decreased chondrocyte proliferation, reduced proliferating chondrocyte survival, delayed onset of hypertrophy, reduced Mmp13 expression, and a failure to maintain interzone cells of the elbow joint, which were not observed previously in another Col2Cre;Tak1f/f model. Deletion of Tak1 in limb mesenchyme resulted in widespread joint fusions likely owing to the differentiation of interzone cells to the chondrocyte lineage. The Prx1Cre;Tak1f/f model also allowed us to identify novel columnar chondrocyte organization and terminal maturation defects owing to the interplay between chondrocytes and the surrounding mesenchyme. Furthermore, both our in vivo models and in vitro cell culture studies demonstrate that loss of Tak1 results in impaired activation of the downstream MAPK target p38, as well as diminished activation of the BMP/SMAD signaling pathway. Taken together, these data demonstrate that TAK1 is a critical regulator of both MAPK and BMP signaling and is necessary for proper cartilage and joint development. © 2010 American Society for Bone and Mineral Research. PMID:20213696

  7. Antioxidant capacity develops with maturation in the deep-diving hooded seal

    Science.gov (United States)

    Vázquez-Medina, José Pablo; Soñanez-Organis, José Guadalupe; Burns, Jennifer M.; Zenteno-Savín, Tania; Ortiz, Rudy M.

    2011-01-01

    SUMMARY Maturation in hooded seals is characterized by the rapid development of their physiological diving capacity and is accompanied by increases in oxidant production but not oxidative damage. To test the hypothesis that the antioxidant system of hooded seals develops as they transition from a terrestrial to an aquatic environment, we obtained the complete cDNA sequence that encodes the NF-E2-related factor 2 (Nrf2), a central regulator of the antioxidant response, and compared Nrf2 mRNA and protein expression levels in muscle samples from neonate, weaned pups and adult hooded seals, along with glutathione (GSH) levels and the activity/protein content of the antioxidant enzymes catalase, glutathione peroxidase (GPx), peroxyredoxin VI (PrxVI), thioredoxin 1 (Trx1), thioredoxin reductase (TrxR), glutaredoxin 1 (Glrx1), glutathione disulphide reductase, glutathione S-transferase and glutamate-cysteine ligase. The Nrf2 of the hooded seal is 1822 bp long and encodes a protein of 606 amino acids with a leucine zipper domain and Keap1-mediated proteosomal degradation residues, which are key for Nrf2 function and regulation. Although neither Nrf2 mRNA nor Nrf2 nuclear protein content are higher in adults than in pups, GSH levels along with GPx, PrxVI, Trx1, TrxR and Glrx1 activity/protein content increase with maturation, suggesting that the potential for peroxide removal increases with development in hooded seals, and that these enzymes contribute to the regulation of the intracellular redox state and the prevention of oxidative damage in these deep-diving mammals. PMID:21832133

  8. Anti-Inflammatory and Antioxidative Effects of Camellia japonica on Human Corneal Epithelial Cells and Experimental Dry Eye: In Vivo and In Vitro Study.

    Science.gov (United States)

    Lee, Hyo Seok; Choi, Joo-Hee; Cui, Lian; Li, Ying; Yang, Jee Myung; Yun, Je-Jung; Jung, Ji Eun; Choi, Won; Yoon, Kyung Chul

    2017-02-01

    To analyze the anti-inflammatory and antioxidative effects of Camellia japonica (CJ) on human corneal epithelial (HCE) cells and its therapeutic effects in a mouse model of experimental dry eye (EDE). Camellia japonica extracts of varying concentrations (0.001%, 0.01%, and 0.1%) were used to treat HCE cells. Dichlorofluorescein diacetate (DCF-DA) and dihydroethidium (DHE) assays were performed. The production of peroxiredoxin (PRX) 1-6 and manganese-dependent superoxide dismutase (MnSOD) in HCE cells was assessed using Western blot analysis. Furthermore, eye drops containing 0.001%, 0.01%, or 0.1% CJ extract or a balanced salt solution (BSS) were applied to the EDE. Clinical parameters were measured 7 days after treatment. The levels of inflammatory markers and intracellular reactive oxygen species (ROS) were measured. Treatment with 0.01% and 0.1% CJ extracts decreased apoptosis in HCE cells. In addition, band intensities of PRX 1, 4, and 5, as well as MnSOD, after hydrogen peroxide (H2O2) treatment showed a significant improvement after pretreatment with 0.01% and 0.1% CJ extracts. Mice treated with 0.1% CJ extract showed significantly improved clinical parameters when compared to those of the EDE control and BSS groups. A significant decrease in the levels of inflammatory markers and intracellular ROS was observed in the 0.01% and 0.1% CJ extract groups. Camellia japonica extracts promoted antioxidative protein expression and suppressed apoptosis in HCE cells. Furthermore, CJ extracts improved clinical signs of dry eye and reduced oxidative stress and the expression of inflammatory markers, suggesting that eye drops containing CJ extract could be used as an adjunctive treatment for dry eye.

  9. Blue light-induced oxidative stress in human corneal epithelial cells: protective effects of ethanol extracts of various medicinal plant mixtures.

    Science.gov (United States)

    Lee, Jee-Bum; Kim, Soo-Hyun; Lee, Seung-Chul; Kim, Hee-Gu; Ahn, Ho-Geun; Li, Zhengri; Yoon, Kyung Chul

    2014-06-12

    To investigate the effects of visible light on human corneal epithelial cells and the impact of natural antioxidants on oxidative stress produced by overexposure to light. Light-emitting diodes with various wavelengths (410-830 nm) were used to irradiate human corneal epithelial cells, and cell viability was assessed. The production of reactive oxygen species (ROS) was analyzed using 2',7'-dichlorodihydrofluorescein diacetate (DCF-DA). Ethyl alcohol (EtOH) extracts were prepared from mixtures of medicinal plants. After application of the EtOH extracts, the free radical scavenging activity was measured using a 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay. The induction of antioxidant enzymes including heme oxygenase-1 (HO-1), peroxiredoxin-1 (Prx-1), catalase (CAT), and superoxide dismutase-2 (SOD-2) by the extracts was evaluated by reverse transcription-polymerase chain reaction and Western blotting. The ability of the extracts to inhibit ROS was also analyzed using DCF-DA. The viability of corneal epithelial cells was diminished after irradiation of blue light (above 10 J at 410 nm and 50 J at 480 nm). Reactive oxygen species production was induced by irradiation at 410 and 480 nm at doses of 5 J/cm(2) and higher. Ethyl alcohol extracts had potent radical scavenging activity. Application of the extracts not only increased the expression of HO-1, Prx-1, CAT, and SOD-2, but it also attenuated the ROS production induced by blue light in a dose-dependent manner. Overexposure to blue light (410-480 nm) may have a harmful effect on human corneal epithelial cells compared with other visible light wavelengths. Medicinal plant extracts can have potent protective effects on blue light-induced oxidative stress. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

  10. Characterization of Withania somnifera leaf transcriptome and expression analysis of pathogenesis-related genes during salicylic acid signaling.

    Directory of Open Access Journals (Sweden)

    Modhumita Ghosh Dasgupta

    Full Text Available Withania somnifera (L. Dunal is a valued medicinal plant with pharmaceutical applications. The present study was undertaken to analyze the salicylic acid induced leaf transcriptome of W. somnifera. A total of 45.6 million reads were generated and the de novo assembly yielded 73,523 transcript contig with average transcript contig length of 1620 bp. A total of 71,062 transcripts were annotated and 53,424 of them were assigned GO terms. Mapping of transcript contigs to biological pathways revealed presence of 182 pathways. Seventeen genes representing 12 pathogenesis-related (PR families were mined from the transcriptome data and their pattern of expression post 17 and 36 hours of salicylic acid treatment was documented. The analysis revealed significant up-regulation of all families of PR genes by 36 hours post treatment except WsPR10. The relative fold expression of transcripts ranged from 1 fold to 6,532 fold. The two families of peroxidases including the lignin-forming anionic peroxidase (WsL-PRX and suberization-associated anionic peroxidase (WsS-PRX recorded maximum expression of 377 fold and 6532 fold respectively, while the expression of WsPR10 was down-regulated by 14 fold. Additionally, the most stable reference gene for normalization of qRT-PCR data was also identified. The effect of SA on the accumulation of major secondary metabolites of W. somnifera including withanoside V, withaferin A and withanolide A was also analyzed and an increase in content of all the three metabolites were detected. This is the first report on expression patterns of PR genes during salicylic acid signaling in W. somnifera.

  11. The presence of sinapyl lignin in Ginkgo biloba cell cultures changes our views of the evolution of lignin biosynthesis.

    Science.gov (United States)

    Uzal, Esther Novo; Gómez Ros, Laura V; Pomar, Federico; Bernal, María A; Paradela, Alberto; Albar, Juan P; Ros Barceló, Alfonso

    2009-02-01

    Suspension cell cultures (SCCs) from one of the oldest seed plants, Ginkgo biloba, show unpredictable alterations in the nature of the lignins, such as is the recruitment of sinapyl alcohol for lignin biosynthesis, compared with the woody tissues of the same species, which lack syringyl (S) lignins. These results show that, in this gymnosperm, the genes involved in sinapyl alcohol biosynthesis are latent and that their regulatory regions respond, by initiating gene expression, to the developmental signals and the environmental clues, which condition its in vitro culture. G. biloba SCCs not only synthesize S lignins but also their extracellular proteome contains both class III peroxidases capable of oxidizing sinapyl alcohol and enzymes involved in H2O2 production, observation which suggests that the peroxidase branch for the oxidative coupling of sinapyl alcohol units into lignins is operative. The incomplete knowledge of the G. biloba peroxidase-encoding genes led us to purify, characterize and partially sequence the peroxidase responsible for monolignol oxidation. When the major peroxidase from G. biloba SCCs (GbPrx) was purified to homogeneity, it showed absorption maxima in the visible region at 414 (Soret band), and at 543 and 570 nm, which calls to mind those shown by low-spin ferric peroxidases. However, the results also showed that the paraperoxidase-like character of GbPrx is not an obstacle for oxidizing the three monolignols compared with high-spin ferric peroxidases. Taken together, these results mean that the time at which the evolutionary gain of the segment of the route that leads to the biosynthesis of S lignins took place in seed plants needs to be revised.

  12. Oxidation of archaeal peroxiredoxin involves a hypervalent sulfur intermediate

    Science.gov (United States)

    Nakamura, Tsutomu; Yamamoto, Takahiko; Abe, Manabu; Matsumura, Hiroyoshi; Hagihara, Yoshihisa; Goto, Tadashi; Yamaguchi, Takafumi; Inoue, Tsuyoshi

    2008-01-01

    The oxidation of thiol groups in proteins is a common event in biochemical processes involving disulfide bond formation and in response to an increased level of reactive oxygen species. It has been widely accepted that the oxidation of a cysteine side chain is initiated by the formation of cysteine sulfenic acid (Cys-SOH). Here, we demonstrate a mechanism of thiol oxidation through a hypervalent sulfur intermediate by presenting crystallographic evidence from an archaeal peroxiredoxin (Prx), the thioredoxin peroxidase from Aeropyrum pernix K1 (ApTPx). The reaction of Prx, which is the reduction of a peroxide, depends on the redox active cysteine side chains. Oxidation by hydrogen peroxide converted the active site peroxidatic Cys-50 of ApTPx to a cysteine sulfenic acid derivative, followed by further oxidation to cysteine sulfinic and sulfonic acids. The crystal structure of the cysteine sulfenic acid derivative was refined to 1.77 Å resolution with Rcryst and Rfree values of 18.8% and 22.0%, respectively. The refined structure, together with quantum chemical calculations, revealed that the sulfenic acid derivative is a type of sulfurane, a hypervalent sulfur compound, and that the Sγ atom is covalently linked to the Nδ1 atom of the neighboring His-42. The reaction mechanism is revealed by the hydrogen bond network around the peroxidatic cysteine and the motion of the flexible loop covering the active site and by quantum chemical calculations. This study provides evidence that a hypervalent sulfur compound occupies an important position in biochemical processes. PMID:18436649

  13. Effects of combinatorial treatment with pituitary adenylate cyclase activating peptide and human mesenchymal stem cells on spinal cord tissue repair.

    Directory of Open Access Journals (Sweden)

    Kuan-Min Fang

    Full Text Available The aim of this study is to understand if human mesenchymal stem cells (hMSCs and neuropeptide pituitary adenylate cyclase-activating polypeptide (PACAP have synergistic protective effect that promotes functional recovery in rats with severe spinal cord injury (SCI. To evaluate the effect of delayed combinatorial therapy of PACAP and hMSCs on spinal cord tissue repair, we used the immortalized hMSCs that retain their potential of neuronal differentiation under the stimulation of neurogenic factors and possess the properties for the production of several growth factors beneficial for neural cell survival. The results indicated that delayed treatment with PACAP and hMSCs at day 7 post SCI increased the remaining neuronal fibers in the injured spinal cord, leading to better locomotor functional recovery in SCI rats when compared to treatment only with PACAP or hMSCs. Western blotting also showed that the levels of antioxidant enzymes, Mn-superoxide dismutase (MnSOD and peroxiredoxin-1/6 (Prx-1 and Prx-6, were increased at the lesion center 1 week after the delayed treatment with the combinatorial therapy when compared to that observed in the vehicle-treated control. Furthermore, in vitro studies showed that co-culture with hMSCs in the presence of PACAP not only increased a subpopulation of microglia expressing galectin-3, but also enhanced the ability of astrocytes to uptake extracellular glutamate. In summary, our in vivo and in vitro studies reveal that delayed transplantation of hMSCs combined with PACAP provides trophic molecules to promote neuronal cell survival, which also foster beneficial microenvironment for endogenous glia to increase their neuroprotective effect on the repair of injured spinal cord tissue.

  14. Enhanced Host-Parasite Resistance Based on Down-Regulation of Phelipanche aegyptiaca Target Genes Is Likely by Mobile Small RNA

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    Neeraj K. Dubey

    2017-09-01

    Full Text Available RNA silencing refers to diverse mechanisms that control gene expression at transcriptional and post-transcriptional levels which can also be used in parasitic pathogens of plants that Broomrapes (Orobanche/Phelipanche spp. are holoparasitic plants that subsist on the roots of a variety of agricultural crops and cause severe negative effects on the yield and yield quality of those crops. Effective methods for controlling parasitic weeds are scarce, with only a few known cases of genetic resistance. In the current study, we suggest an improved strategy for the control of parasitic weeds based on trans-specific gene-silencing of three parasite genes at once. We used two strategies to express dsRNA containing selected sequences of three Phelipanche aegyptiaca genes PaACS, PaM6PR, and PaPrx1 (pma: transient expression using Tobacco rattle virus (TRV:pma as a virus-induced gene-silencing vector and stable expression in transgenic tomato Solanum lycopersicum (Mill. plants harboring a hairpin construct (pBINPLUS35:pma. siRNA-mediated transgene-silencing (20–24 nt was detected in the host plants. Our results demonstrate that the quantities of PaACS and PaM6PR transcripts from P. aegyptiaca tubercles grown on transgenic tomato or on TRV-infected Nicotiana benthamiana plants were significantly reduced. However, only partial reductions in the quantity of PaPrx1 transcripts were observed in the parasite tubercles grown on tomato and on N. benthamiana plants. Concomitant with the suppression of the target genes, there were significant decreases in the number and weight of the parasite tubercles that grew on the host plants, in both the transient and the stable experimental systems. The results of the work carried out using both strategies point to the movement of mobile exogenous siRNA from the host to the parasite, leading to the impaired expression of essential parasite target genes.

  15. Development of Mixed Ion-Electron Conducting Metal Oxides for Solid Oxide Fuel Cells

    Science.gov (United States)

    Kan, Wang Hay

    A solid oxide fuel cell (SOFC) is an energy conversion device, which directly converts chemical fuels (e.g., H2, C xHy) into electricity and heat with high efficiency up to 90%. The by-product of CO2 can be safely sequestrated or subsequently chemically transformed back into fuels (e.g., CO, CH 4) by electrolysis using renewable energy sources such as solar and wind. The state-of-the-art Ni-YSZ anode is de-activated in the presence of ppm level of H2S and forming coke in hydrocarbons. Currently, mixed ion and electron conductors (MIECs) are considered as alternatives for Ni-YSZ in SOFCs. The key goal of the research was to develop mixed ion-electron conducting metal oxides based on B-site disordered perovskite-type Ba(Ca,Nb)1-x MxO3-delta (M = Mn, Fe, Co), the B-site 1:1 ordered perovskite-type (M = Mn, Fe, Co) and the Sr2PbO4-type Sr2Ce1-xPrxO4 for SOFCs. Ba2(Ca,Nb)2-xMxO6-delta was chemically stable in 30 ppm levels of H2S at 600 °C for 24 h and in pure CO2 at 800 °C for 24 h. The thermal expansion coefficients (TEC) of the as-prepared ordered perovskites was found to be comparable to Zr0.84Y0.16O1.92 (YSZ). The near-surface concentration of Fe2+ in Ba2Ca 0.67Fe0.33NbO6-delta was found to be about 3 times higher than that in the bulk sample. The electrochemical performance of Ba2Ca0.67M0.33NbO6-delta was assessed by ac impedance spectroscopy using a YSZ supported half-cell. The area specific polarization resistance (ASR) of all samples was found to decrease with increasing temperature. The ASR for H2 gas oxidation can be correlated to the higher concentration of low valence Fe2+ species near-surface (nano-scale). BaCa0.335M0.165Nb0.5O3-delta crystallizes in the B-site disordered primitive perovskite (space group Pm-3m) at 900 °C in air, which can be converted into the B-site 1:2 ordered perovskite (space group P-3m1) at 1200 °C and the B-site 1:1 ordered double perovskite phase (space group Fm-3m ) at 1300 °C. The chemical stability of the perovskites in CO

  16. Metal-induced self-assembly of peroxiredoxin as a tool for sorting ultrasmall gold nanoparticles into one-dimensional clusters

    Science.gov (United States)

    Ardini, Matteo; Giansanti, Francesco; di Leandro, Luana; Pitari, Giuseppina; Cimini, Annamaria; Ottaviano, Luca; Donarelli, Maurizio; Santucci, Sandro; Angelucci, Francesco; Ippoliti, Rodolfo

    2014-06-01

    Nanomanipulation of matter to create responsive, ordered materials still remains extremely challenging. Supramolecular chemistry has inspired new strategies by which such nanomaterials can be synthesized step by step by exploiting the self-recognition properties of molecules. In this work, the ring-shaped architecture of the 2-Cys peroxiredoxin I protein from Schistosoma mansoni, engineered to have metal ion-binding sites, is used as a template to build up 1D nanoscopic structures through metal-induced self-assembly. Chromatographic and microscopic analyses demonstrate the ability of the protein rings to stack directionally upon interaction with divalent metal ions and form well-defined nanotubes by exploiting the intrinsic recognition properties of the ring surfaces. Taking advantage of such behavior, the rings are then used to capture colloidal Ni2+-functionalized ultrasmall gold nanoparticles and arrange them into 1D arrays through stacking into peapod-like complexes. Finally, as the formation of such nano-peapods strictly depends on nanoparticle dimensions, the peroxiredoxin template is used as a colloidal cut-off device to sort by size the encapsulated nanoparticles. These results open up possibilities in developing Prx-based methods to synthesize new advanced functional materials.Nanomanipulation of matter to create responsive, ordered materials still remains extremely challenging. Supramolecular chemistry has inspired new strategies by which such nanomaterials can be synthesized step by step by exploiting the self-recognition properties of molecules. In this work, the ring-shaped architecture of the 2-Cys peroxiredoxin I protein from Schistosoma mansoni, engineered to have metal ion-binding sites, is used as a template to build up 1D nanoscopic structures through metal-induced self-assembly. Chromatographic and microscopic analyses demonstrate the ability of the protein rings to stack directionally upon interaction with divalent metal ions and form well

  17. In vitro oxime reactivation of red blood cell acetylcholinesterase inhibited by methyl-paraoxon.

    Science.gov (United States)

    Petroianu, G A; Arafat, K; Nurulain, S M; Kuca, K; Kassa, J

    2007-01-01

    Oximes are cholinesterase reactivators of use in poisoning with organophosphorus ester enzyme inhibitors. Pralidoxime (PRX) is the oxime used in the United States. Clinical experience with pralidoxime (and other oximes) is disappointing and the routine use has been questioned. Furthermore oximes are not equally effective against all existent enzyme inhibitors. There is a clear demand for 'broad spectrum' cholinesterase reactivators with a higher efficacy than those clinically available. To meet this need over the years new reactivators of cholinesterase of potential clinical utility have been developed. The purpose of the study was to quantify 'in vitro' the extent of protection conferred by available (pralidoxime and methoxime) and experimental (K-27, K-33 and K-48) oximes, using methyl-paraoxon (methyl-POX) as an esterase inhibitor and to compare the results with those previously obtained using paraoxon (POX) as an inhibitor. Red blood cell (RBC) acetylcholinesterase (AChE) activities in whole blood were measured photometrically in the presence of different methyl-POX concentrations and IC(50) values calculated. Determinations were repeated in the presence of increasing oxime concentrations. The IC(50) of methyl-POX (59 nm) increased with the oxime concentration in a linear manner. The calculated IC(50) values were plotted against the oxime concentrations to obtain an IC(50) shift curve. The slope of the shift curve (tg alpha) was used to quantify the magnitude of the protective effect (nm IC(50) increase per microm reactivator). Based on our determinations the new K-series of reactivators is superior to pralidoxime (tg alpha = 1.9) and methoxime (tg alpha = 0.7), K-27 and K-48 being the outstanding compounds with a tg alpha value of 10 (nm IC(50) increase per microm reactivator), which is approximately five times the reactivator ability of PRX. The tg alpha value determined for K-33 was 6.3. The ranking of reactivator potencies of the examined oximes determined

  18. Functional and morphological changes in endocrine pancreas following cola drink consumption in rats.

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    Matilde Otero-Losada

    Full Text Available We report the effects of long-term cola beverage drinking on glucose homeostasis, endocrine pancreas function and morphology in rats.Wistar rats drank: water (group W, regular cola beverage (group C, sucrose sweetened or "light" cola beverage (group L, artificially sweetened. After 6 months, 50% of the animals in each group were euthanized and the remaining animals consumed water for the next 6 months when euthanasia was performed. Biochemical assays, insulinemia determination, estimation of insulin resistance (HOMA-IR, morphometry and immunohistochemistry evaluations were performed in pancreas.Hyperglycemia (16%, p<0.05, CoQ10 (coenzyme-Q10 decrease (-52%,p<0.01, strong hypertriglyceridemia (2.8-fold, p<0.01, hyperinsulinemia (2.4 fold, p<0.005 and HOMA-IR increase (2.7 fold, p<0.01 were observed in C. Group C showed a decrease in number of α cells (-42%, p<0.01 and β cells (-58%, p<0.001 and a moderate increase in α cells' size after wash-out (+14%, p<0.001. Group L showed reduction in β cells' size (-9%, p<0.001 and only after wash-out (L12 a 19% increase in size (p<0.0001 with 35% decrease in number of α cells (p<0.01. Groups C and L showed increase in α/β-cell ratio which was irreversible only in C (α/β = +38% in C6,+30% in C12, p<0.001vs.W6. Regular cola induced a striking increase in the cytoplasmic expression of Trx1 (Thioredoxin-1 (2.25-fold in C6 vs. W6; 2.7-fold in C12 vs. W12, p<0.0001 and Prx2 (Peroxiredoxin-2 (3-fold in C6 vs. W6; 2-fold in C12 vs. W12, p<0.0001. Light cola induced increase in Trx1 (3-fold and Prx2 (2-fold after wash-out (p<0.0001, L12 vs. W12.Glucotoxicity may contribute to the loss of β cell function with depletion of insulin content. Oxidative stress, suggested by increased expression of thioredoxins and low circulating levels of CoQ10, may follow sustained hyperglycemia. A likely similar panorama may result from the effects of artificially sweetened cola though via other downstream routes.

  19. (La, Pr)0.8Sr0.2FeO3-δ-Sm 0.2Ce0.8O2-δ composite cathode for proton-conducting solid oxide fuel cells

    KAUST Repository

    Chen, Yonghong

    2014-08-01

    Mixed rare-earth (La, Pr)0.8Sr0.2FeO 3-δ-Sm0.2Ce0.8O2-δ (LPSF-SDC) composite cathode was investigated for proton-conducting solid oxide fuel cells based on protonic BaZr0.1Ce0.7Y 0.2O3-δ (BZCY) electrolyte. The powders of La 0.8-xPrxSr0.2FeO3-δ (x = 0, 0.2, 0.4, 0.6), Sm0.2Ce0.8O2-δ (SDC) and BaZr0.1Ce0.7Y0.2O3-δ (BZCY) were synthesized by a citric acid-nitrates self-propagating combustion method. The XRD results indicate that La0.8-xPrxSr 0.2FeO3-δ samples calcined at 950 °C exhibit perovskite structure and there are no interactions between LPSF0.2 and SDC at 1100 °C. The average thermal expansion coefficient (TEC) of LPSF0.2-SDC, BZCY and NiO-BZCY is 12.50 × 10-6 K-1, 13.51 × 10-6 K-1 and 13.47 × 10-6 K -1, respectively, which can provide good thermal compatibility between electrodes and electrolyte. An anode-supported single cell of NiO-BZCY|BZCY|LPSF0.2-SDC was successfully fabricated and operated from 700 °C to 550 °C with humidified hydrogen (∼3% H2O) as fuel and the static air as oxidant. A high maximum power density of 488 mW cm -2, an open-circuit potential of 0.95 V, and a low electrode polarization resistance of 0.071 Ω cm2 were achieved at 700 °C. Preliminary results demonstrate that LPSF0.2-SDC composite is a promising cathode material for proton-conducting solid oxide fuel cells. © 2014, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.

  20. The Role of Polyphenoloxidase, Peroxidase, and β-Glucosidase in Phenolics Accumulation in Olea europaea L. Fruits under Different Water Regimes

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    Marco Cirilli

    2017-05-01

    Full Text Available Olive fruits and oils contain an array of compounds that contribute to their sensory and nutritional properties. Phenolic compounds in virgin oil and olive-derived products have been proven to be highly beneficial for human health, eliciting increasing attention from the food industry and consumers. Although phenolic compounds in olive fruit and oil have been extensively investigated, allowing the identification of the main classes of metabolites and their accumulation patterns, knowledge of the molecular and biochemical mechanisms regulating phenolic metabolism remains scarce. We focused on the role of polyphenoloxidase (PPO, peroxidase (PRX and β-glucosidase (β-GLU gene families and their enzyme activities in the accumulation of phenolic compounds during olive fruit development (35–146 days after full bloom, under either full irrigation (FI or rain-fed (RF conditions. The irrigation regime affected yield, maturation index, mesocarp oil content, fruit size, and pulp-to-pit ratio. Accumulation of fruit phenolics was higher in RF drupes than in FI ones. Members of each gene family were developmentally regulated, affected by water regime, and their transcript levels were correlated with the respective enzyme activities. During the early phase of drupe growth (35–43 days after full bloom, phenolic composition appeared to be linked to β-GLU and PRX activities, probably through their effects on oleuropein catabolism. Interestingly, a higher β-GLU activity was measured in immature RF drupes, as well as a higher content of the oleuropein derivate 3,4-DHPEA-EDA and verbascoside. Activity of PPO enzymes was slightly affected by the water status of trees during ripening (from 120 days after full bloom, but was not correlated with phenolics content. Overall, the main changes in phenolics content appeared soon after the supply of irrigation water and remained thereafter almost unchanged until maturity, despite fruit growth and the progressive

  1. Apoplastic peroxidases are required for salicylic acid-mediated defense against Pseudomonas syringae.

    Science.gov (United States)

    Mammarella, Nicole D; Cheng, Zhenyu; Fu, Zheng Qing; Daudi, Arsalan; Bolwell, G Paul; Dong, Xinnian; Ausubel, Frederick M

    2015-04-01

    Reactive oxygen species (ROS) generated by NADPH oxidases or apoplastic peroxidases play an important role in the plant defense response. Diminished expression of at least two Arabidopsis thaliana peroxidase encoding genes, PRX33 (At3g49110) and PRX34 (At3g49120), as a consequence of anti-sense expression of a heterologous French bean peroxidase gene (asFBP1.1), were previously shown to result in reduced levels of ROS following pathogen attack, enhanced susceptibility to a variety of bacterial and fungal pathogens, and reduced levels of callose production and defense-related gene expression in response to the microbe associated molecular pattern (MAMP) molecules flg22 and elf26. These data demonstrated that the peroxidase-dependent oxidative burst plays an important role in the elicitation of pattern-triggered immunity (PTI). Further work reported in this paper, however, shows that asFBP1.1 antisense plants are not impaired in all PTI-associated responses. For example, some but not all flg22-elicited genes are induced to lower levels by flg22 in asFPB1.1, and callose deposition in asFPB1.1 is similar to wild-type following infiltration with a Pseudomonas syringae hrcC mutant or with non-host P. syringae pathovars. Moreover, asFPB1.1 plants did not exhibit any apparent defect in their ability to mount a hypersensitive response (HR). On the other hand, salicylic acid (SA)-mediated activation of PR1 was dramatically impaired in asFPB1.1 plants. In addition, P. syringae-elicited expression of many genes known to be SA-dependent was significantly reduced in asFBP1.1 plants. Consistent with this latter result, in asFBP1.1 plants the key regulator of SA-mediated responses, NPR1, showed both dramatically decreased total protein abundance and a failure to monomerize, which is required for its translocation into the nucleus. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. Isoenzymatic polymorphism in Citrus spp. and Poncirus trifoliata (L. Raf. (Rutaceae

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    Valdenice Moreira Novelli

    2000-03-01

    Full Text Available Isoenzymatic polymorphism analysis was used to determine genetic variability among species and hybrids of Citrus spp. and one accession of Poncirus trifoliata (L. Raf. Ten enzymatic systems aspartate aminotransferase (AAT, acid phosphatase (ACP, leucine aminopeptidase (LAP, 6-phosphogluconate dehydrogenase (6-PGD, isocitrate dehydrogenase (IDH, phosphoglucoisomerase (PGI, phosphoglucomutase (PGM, diaphorase (DIA, shikimate dehydrogenase (SKD and peroxidase (PRX were analyzed. Twenty loci and 48 alleles were identified. Sweet orange cultivars (C. sinensis (L. Osbeck showed the highest polymorphism with the largest number of heterozygous loci, although the alleles of those loci were the same in all cultivars, with the exception of Westin and Lima graúda. Mandarins (C. reticulata Blanco exhibited diverse patterns, whereas Poncirus trifoliata (L. Raf. showed high variability with all Citrus species and hybrids. Exclusive phenotypes were observed in some enzymatic systems, and similar patterns were found among interspecific hybrids and their putative parents.A análise do polimorfismo isoenzimático foi usada para determinar a variabilidade genética entre espécies e híbridos de Citrus spp. e um acesso da espécie Poncirus trifoliata (L. Raf. Dez diferentes sistemas enzimáticos foram analisados, incluindo aspartato aminotransferase (AAT, fosfatase ácida (ACP, leucina aminopeptidase (LAP, 6-fosfogluconato desidrogenase (6-PGD, isocitrato desidrogenase (IDH, fosfoglucose isomerase (PGI, fosfoglucomutase (PGM, diaforase (DIA, shiquimato desidrogenase (SKD e peroxidase (PRX. Um total de 20 locos e 48 alelos foram identificados. Os cultivares de laranja doce (C. sinensis (L. Osbeck apresentaram um grande número de locos heterozigotos, mas similares entre eles, com exceção dos cultivares Westin e Lima graúda. Os cultivares de mandarim (C. reticulata Blanco apresentaram diferentes padrões entre eles, enquanto que Poncirus trifoliata (L. Raf

  3. COMe: the ontology of bioinorganic proteins

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    Contrino Sergio

    2004-02-01

    Full Text Available Abstract Background Many characterised proteins contain metal ions, small organic molecules or modified residues. In contrast, the huge amount of data generated by genome projects consists exclusively of sequences with almost no annotation. One of the goals of the structural genomics initiative is to provide representative three-dimensional (3-D structures for as many protein/domain folds as possible to allow successful homology modelling. However, important functional features such as metal co-ordination or a type of prosthetic group are not always conserved in homologous proteins. So far, the problem of correct annotation of bioinorganic proteins has been largely ignored by the bioinformatics community and information on bioinorganic centres obtained by methods other than crystallography or NMR is only available in literature databases. Results COMe (Co-Ordination of Metals represents the ontology for bioinorganic and other small molecule centres in complex proteins. COMe consists of three types of entities: 'bioinorganic motif' (BIM, 'molecule' (MOL, and 'complex proteins' (PRX, with each entity being assigned a unique identifier. A BIM consists of at least one centre (metal atom, inorganic cluster, organic molecule and two or more endogenous and/or exogenous ligands. BIMs are represented as one-dimensional (1-D strings and 2-D diagrams. A MOL entity represents a 'small molecule' which, when in complex with one or more polypeptides, forms a functional protein. The PRX entities refer to the functional proteins as well as to separate protein domains and subunits. The complex proteins in COMe are subdivided into three categories: (i metalloproteins, (ii organic prosthetic group proteins and (iii modified amino acid proteins. The data are currently stored in both XML format and a relational database and are available at http://www.ebi.ac.uk/come/. Conclusion COMe provides the classification of proteins according to their 'bioinorganic' features

  4. In silico molecular modeling and docking studies on the leishmanial tryparedoxin peroxidase

    Directory of Open Access Journals (Sweden)

    Ozal Mutlu

    2014-04-01

    Full Text Available Leishmaniasis is one of the most common form of neglected parasitic disease that affects about 350 million people worldwide. Leishmanias have a trypanothione mediated hydroperoxide metabolism to eliminate endogenous or exogenous oxidative agents. Both of 2-Cys peroxiredoxin (Prx and glutathione peroxidase type tryparedoxin peroxidase (Px are the terminal enzymes in the trypanothione dependent detoxification system. Therefore absence of trypanothione redox system in mammals and the sensitivity of trypanosomatids against oxidative stress, enzymes of this pathway are drug targets candidates. In this study, 3D structure of tryparedoxin peroxidase (2-Cys peroxiredoxin type from Leishmania donovani (LdTXNPx was described by homology modeling method based on the template of tryparedoxin peroxidase from Crithidia fasciculata and selected compounds were docked to the active site pocket. The quality of the 3D structure of the model was confirmed by various web based validation programs. When compared secondary and tertiary structure of the model, it showed a typical thioredoxin fold containing a central beta-sheet and three alpha-helices. Docking study showed that the selected compound 2 (CID 16073813 interacted with the active site amino acids and binding energy was -118.675 kcal/mol.

  5. DEWAX Transcription Factor Is Involved in Resistance to Botrytis cinerea in Arabidopsis thaliana and Camelina sativa.

    Science.gov (United States)

    Ju, Seulgi; Go, Young Sam; Choi, Hyo Ju; Park, Jeong Mee; Suh, Mi Chung

    2017-01-01

    The cuticle of land plants is the first physical barrier to protect their aerial parts from biotic and abiotic stresses. DEWAX, an AP2/ERF-type transcription factor, negatively regulates cuticular wax biosynthesis. In this study, we investigated the resistance to Botrytis cinerea in Arabidopsis thaliana and Camelina sativa overexpressing DEWAX and in Arabidopsis dewax mutant. Compared to wild type (WT) leaves, Arabidopsis DEWAX OX and dewax leaves were more and less permeable to toluidine blue dye, respectively. The ROS levels increased in DEWAX OX leaves, but decreased in dewax relative to WT leaves. Compared to WT, DEWAX OX was more resistant, while dewax was more sensitive to B. cinerea; however, defense responses to Pseudomonas syringae pv. tomato DC3000:GFP were inversely modulated. Microarray and RT-PCR analyses indicated that the expression of defense-related genes was upregulated in DEWAX OX, but downregulated in dewax relative to WT. Transactivation assay showed that DEWAX upregulated the expression of PDF1.2a, IGMT1, and PRX37. Chromatin immunoprecipitation assay revealed that DEWAX directly interacts with the GCC-box motifs of PDF1.2a promoter. In addition, ectopic expression of DEWAX increased the tolerance to B. cinerea in C. sativa. Taken together, we suggest that increased ROS accumulation and DEWAX-mediated upregulation of defense-related genes are closely associated with enhanced resistance to B. cinerea in Arabidopsis and C. sativa.

  6. A novel 1-Cys thioredoxin peroxidase gene in Apis cerana cerana: characterization of AccTpx4 and its role in oxidative stresses.

    Science.gov (United States)

    Huaxia, Yifeng; Wang, Fang; Yan, Yan; Liu, Feng; Wang, Hongfang; Guo, Xingqi; Xu, Baohua

    2015-07-01

    Thioredoxin peroxidase (Tpx), also named peroxiredoxin (Prx), is an important peroxidase that can protect organisms against stressful environments. AccTpx4, a 1-Cys thioredoxin peroxidase gene from the Chinese honey bee Apis cerana cerana, was cloned and characterized. The AccTpx4 gene encodes a protein that is predicted to contain the conserved PVCTTE motif from 1-Cys peroxiredoxin. Quantitative real-time PCR (Q-PCR) and Western blotting revealed that AccTpx4 was induced by various oxidative stresses, such as cold, heat, insecticides, H(2)O(2), and HgCl(2). The in vivo peroxidase activity assay showed that recombinant AccTpx4 protein could efficiently degrade H(2)O(2) in the presence of DL-dithiothreitol (DTT). In addition, disc fusion assays revealed that AccTpx4 could function to protect cells against oxidative stresses. These results indicate that AccTpx4 plays an important role in oxidative stress responses and may contribute to the conservation of honeybees.

  7. Inhalation exposure to chloramine T induces DNA damage and inflammation in lung of Sprague-Dawley rats.

    Science.gov (United States)

    Shim, Ilseob; Seo, Gyun-Baek; Oh, Eunha; Lee, Mimi; Kwon, Jung-Taek; Sul, Donggeun; Lee, Byung-Woo; Yoon, Byung-Il; Kim, Pilje; Choi, Kyunghee; Kim, Hyun-Mi

    2013-01-01

    Chloramine T has been widely used as a disinfectant in many areas such as kitchens, laboratories and hospitals. It has been also used as a biocide in air fresheners and deodorants which are consumer products; however, little is known about its toxic effects by inhalation route. This study was performed to identify the subacute inhalation toxicity of chloramine T under whole-body inhalation exposure conditions. Male and female groups of rats were exposed to chloramine T at concentrations of 0.2, 0.9 and 4.0 mg/m³ for 6 hr/day, 5 days/week during 4 weeks. After 28-day repeated inhalation of chloramine T, there were dose-dependently significant DNA damage in the rat tissues evaluated and inflammation was histopathologically noted around the terminal airways of the lung in both genders. As a result of the expression of three types of antioxidant enzymes (SOD-2, GPx-1, PRX-1) in rat's lung after exposure, there was no significant change of all antioxidant enzymes in the male and female rats. The results showed that no observed adverse effect level (NOAEL) was 0.2 mg/m³ in male rats and 0.9 mg/m³ in female rats under the present experimental condition.

  8. Comparison of Soybean Transformation Efficiency and Plant Factors Affecting Transformation during the Agrobacterium Infection Process.

    Science.gov (United States)

    Jia, Yuying; Yao, Xingdong; Zhao, Mingzhe; Zhao, Qiang; Du, Yanli; Yu, Cuimei; Xie, Futi

    2015-08-07

    The susceptibility of soybean genotype to Agrobacterium infection is a key factor for the high level of genetic transformation efficiency. The objective of this study is to evaluate the plant factors related to transformation in cotyledonary nodes during the Agrobacterium infection process. This study selected three genotypes (Williams 82, Shennong 9 and Bert) with high transformation efficiency, which presented better susceptibility to Agrobacterium infection, and three low transformation efficiency genotypes (General, Liaodou 16 and Kottman), which showed a relatively weak susceptibility. Gibberellin (GA) levels and soybean GA20ox2 and CYP707A2 transcripts of high-efficiency genotypes increased and were higher than those of low-efficiency genotypes; however, the opposite performance was shown in abscisic acid (ABA). Higher zeatin riboside (ZR) content and DNA quantity, and relatively higher expression of soybean IPT5, CYCD3 and CYCA3 were obtained in high-efficiency genotypes. High-efficiency genotypes had low methyl jasmonate (MeJA) content, polyphenol oxidase (PPO) and peroxidase (POD) activity, and relatively lower expression of soybean OPR3, PPO1 and PRX71. GA and ZR were positive plant factors for Agrobacterium-mediated soybean transformation by facilitating germination and growth, and increasing the number of cells in DNA synthesis cycle, respectively; MeJA, PPO, POD and ABA were negative plant factors by inducing defence reactions and repressing germination and growth, respectively.

  9. Urm1: an essential regulator of JNK signaling and oxidative stress in Drosophila melanogaster.

    Science.gov (United States)

    Khoshnood, B; Dacklin, I; Grabbe, C

    2016-05-01

    Ubiquitin-related modifier 1 (Urm1) is a ubiquitin-like molecule (UBL) with the dual capacity to act both as a sulphur carrier and posttranslational protein modifier. Here we characterize the Drosophila melanogaster homologues of Urm1 (CG33276) and its E1 activating enzyme Uba4 (CG13090), and show that they function together to induce protein urmylation in vivo. Urm1 conjugation to target proteins in general, and to the evolutionary conserved substrate Peroxiredoxin 5 (Prx5) specifically, is dependent on Uba4. A complete loss of Urm1 is lethal in flies, although a small number of adult zygotic Urm1 (n123) mutant escapers can be recovered. These escapers display a decreased general fitness and shortened lifespan, but in contrast to their S. cerevisiae counterparts, they are resistant to oxidative stress. Providing a molecular explanation, we demonstrate that cytoprotective JNK signaling is increased in Urm1 deficient animals. In agreement, molecular and genetic evidence suggest that elevated activity of the JNK downstream target genes Jafrac1 and gstD1 strongly contributes to the tolerance against oxidative stress displayed by Urm1 (n123) null mutants. In conclusion, Urm1 is a UBL that is involved in the regulation of JNK signaling and the response against oxidative stress in the fruit fly.

  10. Antioxidant Systems are Regulated by Nitric Oxide-Mediated Post-translational Modifications (NO-PTMs)

    Science.gov (United States)

    Begara-Morales, Juan C.; Sánchez-Calvo, Beatriz; Chaki, Mounira; Valderrama, Raquel; Mata-Pérez, Capilla; Padilla, María N.; Corpas, Francisco J.; Barroso, Juan B.

    2016-01-01

    Nitric oxide (NO) is a biological messenger that orchestrates a plethora of plant functions, mainly through post-translational modifications (PTMs) such as S-nitrosylation or tyrosine nitration. In plants, hundreds of proteins have been identified as potential targets of these NO-PTMs under physiological and stress conditions indicating the relevance of NO in plant-signaling mechanisms. Among these NO protein targets, there are different antioxidant enzymes involved in the control of reactive oxygen species (ROS), such as H2O2, which is also a signal molecule. This highlights the close relationship between ROS/NO signaling pathways. The major plant antioxidant enzymes, including catalase, superoxide dismutases (SODs) peroxiredoxins (Prx) and all the enzymatic components of the ascorbate-glutathione (Asa-GSH) cycle, have been shown to be modulated to different degrees by NO-PTMs. This mini-review will update the recent knowledge concerning the interaction of NO with these antioxidant enzymes, with a special focus on the components of the Asa-GSH cycle and their physiological relevance. PMID:26909095

  11. Polimorfismo isoenzimático en cuatro razas y un híbrido de Bactris gasipaes (Palmae

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    Sonia Rojas-Vargas

    1999-12-01

    Full Text Available Se estandarizó un sistema de electroforesis de isoenzimas con tejido de hojas que permitió la identificación del polimorfismo fenético entre cuatro razas y un híbrido de pejibaye Bactris gasipaes provenientes de Brasil, Perú, Bolivia, Panamá y Costa Rica. Las isoenzimas ensayadas fueron: PRX, EST, ACP, ME, DIA, MDH, G6PDH, PGI, SOD, PGM, ADH, GOT, de estas solamente las dos œltimas no mostraron actividad. El resto de isoenzimas mostraron polimorfismo fenético en diferentes grados, por esto se consideran marcadores polimórficos potenciales para estudios de variabilidad genética en pejibaye. Se encontró un locus único en el zimograma de la enzima PRX en las muestras de Utilis-Guápiles (CR, el cual podría usarse como un marcador discriminatorio para esta raza. Se establecieron relaciones de similitud isoenzimática entre las razas Utilis-Guápiles (CR y Tuira-Darién (Pa; Tembé-Chapare (Bo y Pará-Belem (Bra respectivamente, mientras que el híbrido Yurimaguas (Pe se ubicó aparte y ligeramente más cercano a Utilis y Tuira, por esto se considera que posiblemente desciende de padres aún no identificados.The study of genetic diversity in peach palm (Bactris gasipaes K. is important for the breeding work on this palm and to corroborate the hypotheses on its origins. For that purpose it is necessary to use alternative techniques to complement the morphological studies traditionally made. One of the techniques that responds to that need is isozyme electrophoresis. The isozymes are biochemical markers of importance in the study of genetic variability in plants of economic importance, because they are the primary products of genetic expression. This work is an electrophoretic analysis on gels of polyacrilamide to study phenetic relations using twelve isozymes on four races and an spontaneous hybrid of peach palm. The biological material used came from the germplasm bank from Los Diamantes Experimental Station, Guápiles-Costa Rica. Four

  12. Discovering Antioxidant Molecules in the Archaea Domain: Peroxiredoxin Bcp1 from Sulfolobus solfataricus Protects H9c2 Cardiomyoblasts from Oxidative Stress

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    Carmen Sarcinelli

    2016-01-01

    Full Text Available Peroxiredoxins (Prxs are ubiquitous thiol peroxidases that are involved in the reduction of peroxides. It has been reported that prokaryotic Prxs generally show greater structural robustness than their eukaryotic counterparts, making them less prone to inactivation by overoxidation. This difference has inspired the search for new antioxidants from prokaryotic sources that can be used as possible therapeutic biodrugs. Bacterioferritin comigratory proteins (Bcps of the hyperthermophilic archaeon Sulfolobus solfataricus that belong to the Prx family have recently been characterized. One of these proteins, Bcp1, was chosen to determine its antioxidant effects in H9c2 rat cardiomyoblast cells. Bcp1 activity was measured in vitro under physiological temperature and pH conditions that are typical of mammalian cells; the yeast thioredoxin reductase (yTrxR/thioredoxin (yTrx reducing system was used to evaluate enzyme activity. A TAT-Bcp1 fusion protein was constructed to allow its internalization and verify the effect of Bcp1 on H9c2 rat cardiomyoblasts subjected to oxidative stress. The results reveal that TAT-Bcp1 is not cytotoxic and inhibits H2O2-induced apoptosis in H9c2 cells by reducing the H2O2 content inside these cells.

  13. Study on production of useful metabolites by development of advanced cell culture techniques using radiation

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    Chung, Byung Yeoup; Kim, Jinhong; Lee, Seung Sik; Bai, Hyounwoo; An, Byung Chull; Lee, Eun Mi; Lee, Jae Taek; Kim, Mi Ja

    2010-12-15

    The purpose of this project is improvement of investigation, materialization and evaluation techniques on effectiveness for functional natural compounds throughout development of tissue/cell culture techniques for mass production of useful metabolites using radiation. Research scope includes Development of a technique for radiation tissue and cell culture, Database construction for radiation response in plants and radiation effects, Construction of general-purpose national based techniques of cell culture technique using radiation. Main results are as follow: Isolation and identification of radiation induced basI gene; Determination of stresses sensitivities by transformating basI gene into arabidopsis; Isolation and identification of radiation induced chaperon proteins (PaAhpC and yPrxII) from Pseudomonas and yeast, and structural and functional analysis of the proteins; Determination of oxidative and heat resistance by transformating PaAhpC; Isolation and identification of maysin and its derivatives from centipedgrass; Investigation of enhancement technique for improving maysin and its derivatives production using radiation; Investigation of removing undesirable color in maysin and its derivatives using radiation; Determination of the effect of radiation on physiological functions of centipedgrass extracts; Identification of H{sub 2}O{sub 2} removing enzyme in radiation irradiated plant (Spinach); Determination of the effects of centipedgrass extracts on anti-obesity and anti-cancer activities.

  14. Polyethyleneimine (PEI mediated siRNA gene silencing in the Schistosoma mansoni snail host, Biomphalaria glabrata.

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    Matty Knight

    2011-07-01

    Full Text Available An in vivo, non-invasive technique for gene silencing by RNA interference (RNAi in the snail, Biomphalaria glabrata, has been developed using cationic polymer polyethyleneimine (PEI mediated delivery of long double-stranded (ds and small interfering (si RNA. Cellular delivery was evaluated and optimized by using a 'mock' fluorescent siRNA. Subsequently, we used the method to suppress expression of Cathepsin B (CathB with either the corresponding siRNA or dsRNA of this transcript. In addition, the knockdown of peroxiredoxin (Prx at both RNA and protein levels was achieved with the PEI-mediated soaking method. B. glabrata is an important snail host for the transmission of the parasitic digenean platyhelminth, Schistosoma mansoni that causes schistosomiasis in the neotropics. Progress is being made to realize the genome sequence of the snail and to uncover gene expression profiles and cellular pathways that enable the snail to either prevent or sustain an infection. Using PEI complexes, a convenient soaking method has been developed, enabling functional gene knockdown studies with either dsRNA or siRNA. The protocol developed offers a first whole organism method for host-parasite gene function studies needed to identify key mechanisms required for parasite development in the snail host, which ultimately are needed as points for disrupting this parasite mediated disease.

  15. Mechanical and Thermal Properties of Praseodymium Monopnictides: AN Ultrasonic Study

    Science.gov (United States)

    Bhalla, Vyoma; Kumar, Raj; Tripathy, Chinmayee; Singh, Devraj

    2013-09-01

    We have computed ultrasonic attenuation, acoustic coupling constants and ultrasonic velocities of praseodymium monopnictides PrX(X: N, P, As, Sb and Bi) along the , , in the temperature range 100-500 K using higher order elastic constants. The higher order elastic constants are evaluated using Coulomb and Born-Mayer potential with two basic parameters viz. nearest-neighbor distance and hardness parameter in the temperature range of 0-500 K. Several other mechanical and thermal parameters like bulk modulus, shear modulus, Young's modulus, Poisson ratio, anisotropic ratio, tetragonal moduli, Breazeale's nonlinearity parameter and Debye temperature are also calculated. In the present study, the fracture/toughness (B/G) ratio is less than 1.75 which implies that PrX compounds are brittle in nature at room temperature. The chosen material fulfilled Born criterion of mechanical stability. We also found the deviation of Cauchy's relation at higher temperatures. PrN is most stable material as it has highest valued higher order elastic constants as well as the ultrasonic velocity. Further, the lattice thermal conductivity using modified approach of Slack and Berman is determined at room temperature. The ultrasonic attenuation due to phonon-phonon interaction and thermoelastic relaxation mechanisms have been computed using modified Mason's approach. The results with other well-known physical properties are useful for industrial applications.

  16. Quantitative proteomic analysis of pregnancy-related proteins from peripheral blood mononuclear cells during pregnancy in pigs.

    Science.gov (United States)

    Chae, Jung-Il; Kim, Jumi; Lee, Seong Goo; Koh, Min Whan; Jeon, Young-Joo; Kim, Dong-Wook; Ko, Seon Mi; Seo, Kang Seok; Lee, Hak Kyo; Choi, Nag-Jin; Cho, Seong-Keun; Ryu, Joohyun; Kang, Sunghyun; Lee, Dong-Seok; Chung, Hyung-Min; Koo, Deog-Bon

    2012-10-01

    Information obtained from peripheral blood could help us understand the underlying mechanisms in autoimmune diseases, cancer, pregnancy, and other conditions. In this paper, we present the protein map of porcine peripheral blood mononuclear cells (PBMC) to better understand the molecular expression changes that occur during pregnancy using proteomic analysis. We detected 94 differentially expressed proteins in pregnant vs. non-pregnant (NP) pigs, and a representative set of the proteins was subjected to LC-MS/MS analysis. Furthermore, the identified proteins were categorized according to their biological process and molecular function. By classifying the proteins according to their functions, a large number of differentially regulated proteins involved in anti-oxidant, detoxification and stress response pathways were found, including peroxiredoxin (PRX) 1, 2, and 6, glutathione-S-transferase (GST), annexin A2, and A6, and heat shock protein 27 (HSP 27) during pregnancy (pregnancy d of E40, embryonic day 40; E70, embryonic day 70; and E93, embryonic day 93) compared with non-pregnancy. In this study, a proteomic approach utilizing 2-DE and LC-MS/MS was applied to evaluate specific molecular expression changes during pregnancy compared with non-pregnancy. Together, these data offer new information about the proteome map and factors that are differentially regulated during maintenance of normal pregnancy. Copyright © 2012 Elsevier B.V. All rights reserved.

  17. DEWAX Transcription Factor Is Involved in Resistance to Botrytis cinerea in Arabidopsis thaliana and Camelina sativa

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    Seulgi Ju

    2017-07-01

    Full Text Available The cuticle of land plants is the first physical barrier to protect their aerial parts from biotic and abiotic stresses. DEWAX, an AP2/ERF-type transcription factor, negatively regulates cuticular wax biosynthesis. In this study, we investigated the resistance to Botrytis cinerea in Arabidopsis thaliana and Camelina sativa overexpressing DEWAX and in Arabidopsis dewax mutant. Compared to wild type (WT leaves, Arabidopsis DEWAX OX and dewax leaves were more and less permeable to toluidine blue dye, respectively. The ROS levels increased in DEWAX OX leaves, but decreased in dewax relative to WT leaves. Compared to WT, DEWAX OX was more resistant, while dewax was more sensitive to B. cinerea; however, defense responses to Pseudomonas syringae pv. tomato DC3000:GFP were inversely modulated. Microarray and RT-PCR analyses indicated that the expression of defense-related genes was upregulated in DEWAX OX, but downregulated in dewax relative to WT. Transactivation assay showed that DEWAX upregulated the expression of PDF1.2a, IGMT1, and PRX37. Chromatin immunoprecipitation assay revealed that DEWAX directly interacts with the GCC-box motifs of PDF1.2a promoter. In addition, ectopic expression of DEWAX increased the tolerance to B. cinerea in C. sativa. Taken together, we suggest that increased ROS accumulation and DEWAX-mediated upregulation of defense-related genes are closely associated with enhanced resistance to B. cinerea in Arabidopsis and C. sativa.

  18. BIM Guidelines Inform Facilities Management Databases: A Case Study over Time

    Directory of Open Access Journals (Sweden)

    Karen Kensek

    2015-08-01

    Full Text Available A building information model (BIM contains data that can be accessed and exported for other uses during the lifetime of the building especially for facilities management (FM and operations. Working under the guidance of well-designed BIM guidelines to insure completeness and compatibility with FM software, architects and contractors can deliver an information rich data model that is valuable to the client. Large owners such as universities often provide these detailed guidelines and deliverable requirements to their building teams. Investigation of the University of Southern California (USC Facilities Management Service’s (FMS website showed a detailed plan including standards, file names, parameter lists, and other requirements of BIM data, which were specifically designated for facilities management use, as deliverables on new construction projects. Three critical details were also unearthed in the reading of these documents: Revit was the default BIM software; COBie was adapted to help meet facilities management goals; and EcoDomus provided a display of the collected data viewed through Navisworks. Published accounts about the Cinema Arts Complex developed with and under these guidelines reported positive results. Further examination with new projects underway reveal the rapidly changing relational database landscape evident in the new USC “Project Record Revit Requirement Execution Plan (PRxP”.

  19. Comparison of Soybean Transformation Efficiency and Plant Factors Affecting Transformation during the Agrobacterium Infection Process

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    Yuying Jia

    2015-08-01

    Full Text Available The susceptibility of soybean genotype to Agrobacterium infection is a key factor for the high level of genetic transformation efficiency. The objective of this study is to evaluate the plant factors related to transformation in cotyledonary nodes during the Agrobacterium infection process. This study selected three genotypes (Williams 82, Shennong 9 and Bert with high transformation efficiency, which presented better susceptibility to Agrobacterium infection, and three low transformation efficiency genotypes (General, Liaodou 16 and Kottman, which showed a relatively weak susceptibility. Gibberellin (GA levels and soybean GA20ox2 and CYP707A2 transcripts of high-efficiency genotypes increased and were higher than those of low-efficiency genotypes; however, the opposite performance was shown in abscisic acid (ABA. Higher zeatin riboside (ZR content and DNA quantity, and relatively higher expression of soybean IPT5, CYCD3 and CYCA3 were obtained in high-efficiency genotypes. High-efficiency genotypes had low methyl jasmonate (MeJA content, polyphenol oxidase (PPO and peroxidase (POD activity, and relatively lower expression of soybean OPR3, PPO1 and PRX71. GA and ZR were positive plant factors for Agrobacterium-mediated soybean transformation by facilitating germination and growth, and increasing the number of cells in DNA synthesis cycle, respectively; MeJA, PPO, POD and ABA were negative plant factors by inducing defence reactions and repressing germination and growth, respectively.

  20. Conditional inactivation of Has2 reveals a crucial role for hyaluronan in skeletal growth, patterning, chondrocyte maturation and joint formation in the developing limb.

    Science.gov (United States)

    Matsumoto, Kazu; Li, Yingcui; Jakuba, Caroline; Sugiyama, Yoshinori; Sayo, Tetsuya; Okuno, Misako; Dealy, Caroline N; Toole, Bryan P; Takeda, Junji; Yamaguchi, Yu; Kosher, Robert A

    2009-08-01

    The glycosaminoglycan hyaluronan (HA) is a structural component of extracellular matrices and also interacts with cell surface receptors to directly influence cell behavior. To explore functions of HA in limb skeletal development, we conditionally inactivated the gene for HA synthase 2, Has2, in limb bud mesoderm using mice that harbor a floxed allele of Has2 and mice carrying a limb mesoderm-specific Prx1-Cre transgene. The skeletal elements of Has2-deficient limbs are severely shortened, indicating that HA is essential for normal longitudinal growth of all limb skeletal elements. Proximal phalanges are duplicated in Has2 mutant limbs indicating an involvement of HA in patterning specific portions of the digits. The growth plates of Has2-deficient skeletal elements are severely abnormal and disorganized, with a decrease in the deposition of aggrecan in the matrix and a disruption in normal columnar cellular relationships. Furthermore, there is a striking reduction in the number of hypertrophic chondrocytes and in the expression domains of markers of hypertrophic differentiation in the mutant growth plates, indicating that HA is necessary for the normal progression of chondrocyte maturation. In addition, secondary ossification centers do not form in the central regions of Has2 mutant growth plates owing to a failure of hypertrophic differentiation. In addition to skeletal defects, the formation of synovial joint cavities is defective in Has2-deficient limbs. Taken together, our results demonstrate that HA has a crucial role in skeletal growth, patterning, chondrocyte maturation and synovial joint formation in the developing limb.

  1. Isozyme and RAPD studies in Prosopis glandulosa and P. Velutina (Leguminosae, Mimosoideae

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    Bessega Cecilia

    2000-01-01

    Full Text Available Allozyme and random amplified polymorphic DNA (RAPD techniques have been compared for their usefulness for genetic and taxonomic studies in Prosopis glandulosa and P. velutina populations. Isozymes and RAPDs yielded similarly high estimates of genetic variability. Genetic structure and differentiation were analyzed through non-hierarchical Wright's F DT. For all populations considered, both markers produced low gene flow (Nm 1, in agreement with that expected for conspecific populations. However, in RAPD data the expected reduction in F DT and the increase in Nm were not observed. Correlation between F DT and geographical distance matrices (Mantel test for all populations was significant (P = 0.02 when based on isozymes, but not so (P = 0.33 when based on RAPDs. No significant associations among genetic and geographical or climatic variables were observed. Two isoenzyme systems (GOT and PRX enabled us to distinguish between P. glandulosa and P. velutina, but no diagnostic band for recognition of populations or species studied here were detected by RAPD. However, RAPD markers showed higher values for genetic differentiation among conspecific populations of P. glandulosa and a lower coefficient of variation than those obtained from isozymes.

  2. The sigma-1 receptor-zinc finger protein 179 pathway protects against hydrogen peroxide-induced cell injury.

    Science.gov (United States)

    Su, Tzu-Chieh; Lin, Shu-Hui; Lee, Pin-Tse; Yeh, Shiu-Hwa; Hsieh, Tsung-Hsun; Chou, Szu-Yi; Su, Tsung-Ping; Hung, Jan-Jong; Chang, Wen-Chang; Lee, Yi-Chao; Chuang, Jian-Ying

    2016-06-01

    The accumulation of reactive oxygen species (ROS) have implicated the pathogenesis of several human diseases including neurodegenerative disorders, stroke, and traumatic brain injury, hence protecting neurons against ROS is very important. In this study, we focused on sigma-1 receptor (Sig-1R), a chaperone at endoplasmic reticulum, and investigated its protective functions. Using hydrogen peroxide (H2O2)-induced ROS accumulation model, we verified that apoptosis-signaling pathways were elicited by H2O2 treatment. However, the Sig-1R agonists, dehydroepiandrosterone (DHEA) and DHEA sulfate (DHEAS), reduced the activation of apoptotic pathways significantly. By performing protein-protein interaction assays and shRNA knockdown of Sig-1R, we identified the brain Zinc finger protein 179 (Znf179) as a downstream target of Sig-1R regulation. The neuroprotective effect of Znf179 overexpression was similar to that of DHEAS treatment, and likely mediated by affecting the levels of antioxidant enzymes. We also quantified the levels of peroxiredoxin 3 (Prx3) and superoxide dismutase 2 (SOD2) in the hippocampi of wild-type and Znf179 knockout mice, and found both enzymes to be reduced in the knockout versus the wild-type mice. In summary, these results reveal that Znf179 plays a novel role in neuroprotection, and Sig-1R agonists may be therapeutic candidates to prevent ROS-induced damage in neurodegenerative and neurotraumatic diseases. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. The role of sulfenic acids in cellular redox signaling: Reconciling chemical kinetics and molecular detection strategies.

    Science.gov (United States)

    Heppner, David E; Janssen-Heininger, Yvonne M W; van der Vliet, Albert

    2017-02-15

    The reversible oxidation of protein cysteine residues is well recognized as an important regulatory mechanism in redox-dependent cell signaling. Cysteine oxidation is diverse in nature and involves various post-translational modifications (sulfenic acids, disulfides, etc.) and the specific functional or structural impact of these specific oxidative events is still poorly understood. The proximal product of protein cysteine oxidation by biological reactive oxygen species (ROS) is sulfenic acid (Cys-SOH), and experimental evidence is accruing for the formation of Cys-SOH as intermediate in protein cysteine oxidation in various biological settings. However, the plausibility of protein Cys-SH oxidation by ROS has often been put in question because of slow reaction kinetics compared to more favorable reactions with abundant thiol-based reductants such as peroxiredoxins (Prx) or glutathione (GSH). This commentary aims to address this controversy by highlighting the unique physical properties in cells that may restrict ROS diffusion and allow otherwise less favorable cysteine oxidation of proteins. Some limitations of analytical tools to assess Cys-SOH are also discussed. We conclude that formation of Cys-SOH in biological systems cannot always be predicted based on kinetic analyses in homogenous solution, and may be facilitated by unique structural and physical properties of Cys-containing proteins within e.g. signaling complexes. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Dynamic chemical expansion of thin-film non-stoichiometric oxides at extreme temperatures.

    Science.gov (United States)

    Swallow, Jessica G; Kim, Jae Jin; Maloney, John M; Chen, Di; Smith, James F; Bishop, Sean R; Tuller, Harry L; Van Vliet, Krystyn J

    2017-07-01

    Actuator operation in increasingly extreme and remote conditions requires materials that reliably sense and actuate at elevated temperatures, and over a range of gas environments. Design of such materials will rely on high-temperature, high-resolution approaches for characterizing material actuation in situ. Here, we demonstrate a novel type of high-temperature, low-voltage electromechanical oxide actuator based on the model material PrxCe1-xO2-δ (PCO). Chemical strain and interfacial stress resulted from electrochemically pumping oxygen into or out of PCO films, leading to measurable film volume changes due to chemical expansion. At 650 °C, nanometre-scale displacement and strain of >0.1% were achieved with electrical bias values <0.1 V, low compared to piezoelectrically driven actuators, with strain amplified fivefold by stress-induced structural deflection. This operando measurement of films 'breathing' at second-scale temporal resolution also enabled detailed identification of the controlling kinetics of this response, and can be extended to other electrochemomechanically coupled oxide films at extreme temperatures.

  5. Fungal endophytes of Catharanthus roseus enhance vindoline content by modulating structural and regulatory genes related to terpenoid indole alkaloid biosynthesis.

    Science.gov (United States)

    Pandey, Shiv S; Singh, Sucheta; Babu, C S Vivek; Shanker, Karuna; Srivastava, N K; Shukla, Ashutosh K; Kalra, Alok

    2016-05-25

    Not much is known about the mechanism of endophyte-mediated induction of secondary metabolite production in Catharanthus roseus. In the present study two fungal endophytes, Curvularia sp. CATDLF5 and Choanephora infundibulifera CATDLF6 were isolated from the leaves of the plant that were found to enhance vindoline content by 229-403%. The isolated endophytes did not affect the primary metabolism of the plant as the maximum quantum efficiency of PSII, net CO2 assimilation, plant biomass and starch content of endophyte-inoculated plants was similar to endophyte-free control plants. Expression of terpenoid indole alkaloid (TIA) pathway genes, geraniol 10-hydroxylase (G10H), tryptophan decarboxylase (TDC), strictosidine synthase (STR), 16-hydoxytabersonine-O-methyltransferase (16OMT), desacetoxyvindoline-4-hydroxylase (D4H), deacetylvindoline-4-O-acetyltransferase (DAT) were upregulated in endophyte-inoculated plants. Endophyte inoculation upregulated the expression of the gene for transcriptional activator octadecanoid-responsive Catharanthus AP2-domain protein (ORCA3) and downregulated the expression of Cys2/His2-type zinc finger protein family transcriptional repressors (ZCTs). The gene for the vacuolar class III peroxidase (PRX1), responsible for coupling vindoline and catharanthine, was upregulated in endophyte-inoculated plants. These endophytes may enhance vindoline production by modulating the expression of key structural and regulatory genes of vindoline biosynthesis without affecting the primary metabolism of the host plant.

  6. Mussel oligopeptides protect human fibroblasts from hydrogen peroxide (H2O2)-induced premature senescence.

    Science.gov (United States)

    Zhou, Yue; Dong, Ying; Xu, Qing-Gang; Zhu, Shu-Yun; Tian, Shi-Lei; Huo, Jing-jing; Hao, Ting-Ting; Zhu, Bei-Wei

    2014-01-01

    Mussel bioactive peptides have been viewed as mediators to maximize the high quality of life. In this study, the anti-aging activities of mussel oligopeptides were evaluated using H2O2-induced prematurely senescent MRC-5 fibroblasts. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and flow cytometry displayed that exposure to H2O2 led to the loss of cell viability and cell cycle arrest. In addition, H2O2 caused the elevation of senescence-associated-β-galactosidase (SA-β-gal) activity and formation of senescence-associated heterochromatin foci (SAHF). It was found that pretreatment with mussel oligopeptides could significantly attenuate these properties associated with cellular senescence. Mussel oligopeptides also led to the increase of glutathione (GSH) level and mitochondrial transmembrane potential (Δψm) recovery. In addition, mussel oligopeptides resulted in an improvement in transcriptional activity of peroxiredoxin 1 (Prx1), nicotinamide phosphoribosyltransferase (NAMPT) and sirtuin 1 (SIRT1). This study revealed that mussel oligopeptides could protect against cellular senescence induced by H2O2, and the effects were closely associated with redox cycle modulating and potentiating the SIRT1 pathway. These findings provide new insights into the beneficial role of mussel bioactive peptides on retarding senescence process. Crown Copyright © 2013. Published by Elsevier Ireland Ltd. All rights reserved.

  7. Computational identification of a new SelD-like family that may participate in sulfur metabolism in hyperthermophilic sulfur-reducing archaea.

    Science.gov (United States)

    Li, Gao-Peng; Jiang, Liang; Ni, Jia-Zuan; Liu, Qiong; Zhang, Yan

    2014-10-17

    Selenium (Se) and sulfur (S) are closely related elements that exhibit similar chemical properties. Some genes related to S metabolism are also involved in Se utilization in many organisms. However, the evolutionary relationship between the two utilization traits is unclear. In this study, we conducted a comparative analysis of the selenophosphate synthetase (SelD) family, a key protein for all known Se utilization traits, in all sequenced archaea. Our search showed a very limited distribution of SelD and Se utilization in this kingdom. Interestingly, a SelD-like protein was detected in two orders of Crenarchaeota: Sulfolobales and Thermoproteales. Sequence and phylogenetic analyses revealed that SelD-like protein contains the same domain and conserved functional residues as those of SelD, and might be involved in S metabolism in these S-reducing organisms. Further genome-wide analysis of patterns of gene occurrence in different thermoproteales suggested that several genes, including SirA-like, Prx-like and adenylylsulfate reductase, were strongly related to SelD-like gene. Based on these findings, we proposed a simple model wherein SelD-like may play an important role in the biosynthesis of certain thiophosphate compound. Our data suggest novel genes involved in S metabolism in hyperthermophilic S-reducing archaea, and may provide a new window for understanding the complex relationship between Se and S metabolism in archaea.

  8. AMRI-59 has a role of radiosensitizer via enhancement of γ-ionizing radiation-induced apoptotic cell death

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Wan Gi; Cho, Jeong Hyun; Kim, Ju Yeon; Hwang, Sang Gu; Um, Hong Duck; Park, Jong Kuk [KAERI, Daejeon (Korea, Republic of)

    2016-05-15

    Recent in vitro studies have suggested that may increase the invasiveness of some cancer cells (e.g., glioma, hepatocellular carcinoma, and pancreatic cancer cells) by stimulating several intracellular signaling pathways and in vivo studies have found that radiotherapy of primary tumor sites may promote metastasis. Thus, in addition to having therapeutic effects, IR might promote the malignant traits of surviving cancer cells. The existing efforts to develop radiosensitizing agents have focused on overcoming radioresistance and reducing damage to normal tissues. Recently, concepts of personalized- or precision medicine are developed due to advancement of mega data technique, which provide new targets to develop new anti-cancer drugs. In this study, we sought to identify the radiosensitizer effect of AMRI-59 in vitro and in vivo., which is recently developed specific inhibitor of peroxiredoxin (Prx) I. AMRI-59 enhanced radiation-induced cell death and its mean calculated dose enhancement ratio was 1.26. We also found combination of AMRI-59 and IR In a xenograft assay, the combined PHCM and radiation group showed 14.3 days of growth delay versus the control in terms of tumor growth. The enhancement factor of this combined treatment was determined to be 2.03.

  9. Multiparameter-based bioassay of 2-(4-chlorophenyl)-4-(4-methoxyphenyl) quinazoline, a newly-synthesized quinazoline derivative, toward Microcystis aeruginosa HAB5100 (cyanobacteria).

    Science.gov (United States)

    Zhao, Yang; Liu, Weisheng; Li, Qi; Yang, Qin; Chai, Wenbo; Zeng, Mengjing; Li, Renhui; Peng, Yiyuan

    2015-03-01

    Quinazoline derivatives have wide biological activities and therapeutic properties, implying their potential for development and application on a large scale. In the present study, 2-(4-chlorophenyl)-4-(4-methoxyphenyl) quinazoline (CMQ), was selected to examine its effect on unicellular cyanobacteria, Microcystis aeruginosa by evaluating growth, physiological and molecular responses. Growth was inhibited by CMQ, with a 96 h EC50 of 1.93 ± 0.19 mg L(-1). The up-regulated expression of prx was shown, reflecting that oxidative stress might be a toxic factor of CMQ. At higher concentrations of CMQ, the quantum yields of Y(II) and Y(NPQ) in photosystem II decreased seriously and Y(NO) increased sharply, and psbA gene encoding for D1 protein was over-expressed. These results demonstrated that high concentrations of CMQ had different inhibitory targets associated with photosystem electron transport and with sites beyond the electron transport chain, leading to severe toxicity.

  10. Treatment of lower urinary tract symptoms: agents for intraprostatic injection.

    Science.gov (United States)

    Andersson, Karl-Erik

    2013-04-01

    When the currently available pharmacotherapeutic principles used for treatment of male lower urinary tract symptoms (LUTS) fail, transurethral resection of the prostate still remains the widely applied gold-standard therapy, since the majority of minimally invasive therapies have not achieved the same efficacy and/or lack an evidence base to support their routine use. Intraprostatic injection therapy, which probably is the oldest minimally invasive surgical treatment, has not been widely used, but recent reports of successful treatments with several new agents have renewed interest in this approach. Anhydrous ethanol still seems to be one of the most extensively studied injectables to date, but intraprostatic injection of botulinum toxin has received much recent attention, with regard to both its mechanism of action and efficacy. In addition, other agents such as NX-1207 and PRX302 have been reported to have promising effects. Injection therapy, using the transperineal, transrectal and transurethral routes for delivery of the active compounds, seems to be an effective minimally invasive surgical therapy for LUTS associated with benign prostatic hyperplasia (BPH). However, further studies on mechanisms of action of the novel agents used, and controlled clinical trials documenting their efficacy and side-effects (which are largely lacking), are needed before their place in the treatment of BPH/LUTS can be properly assessed.

  11. Intraprostatic injections for lower urinary tract symptoms treatment.

    Science.gov (United States)

    Andersson, Karl-Erik

    2015-01-01

    The purpose of this study is to review and discuss recently published (2013-2014) experimental and clinical studies of intraprostatic injection therapy as an alternative treatment of lower urinary tract symptoms (LUTS). Recent focus has been on intraprostatic injection of botulinum toxin both with regard to mechanism of action and efficacy. In contrast to the promising findings in several previous studies, a recent large, randomized, placebo-controlled trial found no differences between onabotulinumtoxin A treatment and placebo. There is little new information on the use of anhydrous ethanol and agents such as NX-1207 and PRX302, which previously have been reported to have promising effects. Intraprostatic injection of different agents as a minimally invasive surgical therapy for LUTS associated with benign prostatic hyperplasia seems attractive and may have a potential as a treatment alternative, but so far, available results are not convincing. Further studies on the mechanisms of action of novel agents, and controlled clinical trials documenting their efficacy and side-effects when injected into the prostate are needed before their place in the treatment of benign prostatic hyperplasia/LUTS can be properly assessed.

  12. Fungal endophytes of Catharanthus roseus enhance vindoline content by modulating structural and regulatory genes related to terpenoid indole alkaloid biosynthesis

    Science.gov (United States)

    Pandey, Shiv S.; Singh, Sucheta; Babu, C. S. Vivek; Shanker, Karuna; Srivastava, N. K.; Shukla, Ashutosh K.; Kalra, Alok

    2016-01-01

    Not much is known about the mechanism of endophyte-mediated induction of secondary metabolite production in Catharanthus roseus. In the present study two fungal endophytes, Curvularia sp. CATDLF5 and Choanephora infundibulifera CATDLF6 were isolated from the leaves of the plant that were found to enhance vindoline content by 229–403%. The isolated endophytes did not affect the primary metabolism of the plant as the maximum quantum efficiency of PSII, net CO2 assimilation, plant biomass and starch content of endophyte-inoculated plants was similar to endophyte-free control plants. Expression of terpenoid indole alkaloid (TIA) pathway genes, geraniol 10-hydroxylase (G10H), tryptophan decarboxylase (TDC), strictosidine synthase (STR), 16-hydoxytabersonine-O-methyltransferase (16OMT), desacetoxyvindoline-4-hydroxylase (D4H), deacetylvindoline-4-O-acetyltransferase (DAT) were upregulated in endophyte-inoculated plants. Endophyte inoculation upregulated the expression of the gene for transcriptional activator octadecanoid-responsive Catharanthus AP2-domain protein (ORCA3) and downregulated the expression of Cys2/His2-type zinc finger protein family transcriptional repressors (ZCTs). The gene for the vacuolar class III peroxidase (PRX1), responsible for coupling vindoline and catharanthine, was upregulated in endophyte-inoculated plants. These endophytes may enhance vindoline production by modulating the expression of key structural and regulatory genes of vindoline biosynthesis without affecting the primary metabolism of the host plant. PMID:27220774

  13. Induction of heme oxygenase-1 by chamomile protects murine macrophages against oxidative stress.

    Science.gov (United States)

    Bhaskaran, Natarajan; Shukla, Sanjeev; Kanwal, Rajnee; Srivastava, Janmejai K; Gupta, Sanjay

    2012-06-27

    Protection of cells from oxidative insult may be possible through direct scavenging of reactive oxygen species, or through stimulation of intracellular antioxidant defense mechanisms by induction of antioxidant gene expression. In this study we investigated the cytoprotective effect of chamomile and elucidated the underlying mechanisms. The cytoprotective effect of chamomile was examined on H(2)O(2)-induced cellular stress in RAW 264.7 murine macrophages. RAW 264.7 murine macrophages treated with chamomile were protected from cell death caused by H(2)O(2). Treatment with 50μM H(2)O(2) for 6h caused significant increase in cellular stress accompanied by cell death in RAW 264.7 macrophages. Pretreatment with chamomile at 10-20μg/mL for 16h followed by H(2)O(2) treatment protected the macrophages against cell death. Chamomile exposure significantly increased the expression of antioxidant enzymes viz. heme oxygenase-1 (HO-1), peroxiredoxin-1 (Prx-1), and thioredoxin-1 (Trx-1) in a dose-dependent manner, compared with their respective controls. Chamomile increased nuclear translocation of Nrf2 with increased phosphorylated Nrf2 levels, and binding to the antioxidant response element in the nucleus. These molecular findings for the first time provide insights into the mechanisms underlying the induction of phase 2 enzymes through the Keap1-Nrf2 signaling pathway by chamomile, and provide evidence that chamomile possesses antioxidant and cytoprotective properties. Copyright © 2012 Elsevier Inc. All rights reserved.

  14. Studi Perancangan Jaringan Worldwide Interoperability For Microwave Access (Wimax Di Area Banyumas

    Directory of Open Access Journals (Sweden)

    Alfin Hikmaturokhman

    2012-05-01

    Full Text Available At present the need for higher internet connection along with the age which is growing so fast. Then there is the latest breakthrough in telecomunications that is WiMAX technology is a wireless broadband technology reffered the IEEE 802.16 standard. WiMAX technology comes with a network of excellence in aspects of data access speed, wide area coverage and the presence of QoS is can allocate frequencies in accordance with user needs using OFDM technology. WiMAX technology can reach area far as 50 kilometers, also allows user equipment (customer premise equipment or CPE to get a broadband connection without having a direct path (non line of sight, NLOS to the base station (BS and provides a total data rate of up to 75 Mbps. Results of this Final project assumed that the area where will be design is Banyumas district. Then final project results of the PRX -100.31 dB; the Total Margin of 23.56 dB; Path los of 134.5 dB; gamma (? of 4.375; Frequency correction factor (?PLf of 0,36; antenna correction factor (?PLh is -3,25; Radius Cells (d is approximately 1995 meters; area of cell is at 10,34010495 km2 and the number of cells 133

  15. Fusarium oxysporum triggers tissue-specific transcriptional reprogramming in Arabidopsis thaliana.

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    Rebecca Lyons

    Full Text Available Some of the most devastating agricultural diseases are caused by root-infecting pathogens, yet the majority of studies on these interactions to date have focused on the host responses of aerial tissues rather than those belowground. Fusarium oxysporum is a root-infecting pathogen that causes wilt disease on several plant species including Arabidopsis thaliana. To investigate and compare transcriptional changes triggered by F. oxysporum in different Arabidopsis tissues, we infected soil-grown plants with F. oxysporum and subjected root and leaf tissue harvested at early and late timepoints to RNA-seq analyses. At least half of the genes induced or repressed by F. oxysporum showed tissue-specific regulation. Regulators of auxin and ABA signalling, mannose binding lectins and peroxidases showed strong differential expression in root tissue. We demonstrate that ARF2 and PRX33, two genes regulated in the roots, promote susceptibility to F. oxysporum. In the leaves, defensins and genes associated with the response to auxin, cold and senescence were strongly regulated while jasmonate biosynthesis and signalling genes were induced throughout the plant.

  16. Dynamic chemical expansion of thin-film non-stoichiometric oxides at extreme temperatures

    Science.gov (United States)

    Swallow, Jessica G.; Kim, Jae Jin; Maloney, John M.; Chen, Di; Smith, James F.; Bishop, Sean R.; Tuller, Harry L.; van Vliet, Krystyn J.

    2017-07-01

    Actuator operation in increasingly extreme and remote conditions requires materials that reliably sense and actuate at elevated temperatures, and over a range of gas environments. Design of such materials will rely on high-temperature, high-resolution approaches for characterizing material actuation in situ. Here, we demonstrate a novel type of high-temperature, low-voltage electromechanical oxide actuator based on the model material PrxCe1-xO2-δ (PCO). Chemical strain and interfacial stress resulted from electrochemically pumping oxygen into or out of PCO films, leading to measurable film volume changes due to chemical expansion. At 650 °C, nanometre-scale displacement and strain of >0.1% were achieved with electrical bias values <0.1 V, low compared to piezoelectrically driven actuators, with strain amplified fivefold by stress-induced structural deflection. This operando measurement of films `breathing’ at second-scale temporal resolution also enabled detailed identification of the controlling kinetics of this response, and can be extended to other electrochemomechanically coupled oxide films at extreme temperatures.

  17. Immunoproteomic Analysis of Antibody Responses to Extracellular Proteins of Candida albicans Revealing the Importance of Glycosylation for Antigen Recognition.

    Science.gov (United States)

    Luo, Ting; Krüger, Thomas; Knüpfer, Uwe; Kasper, Lydia; Wielsch, Natalie; Hube, Bernhard; Kortgen, Andreas; Bauer, Michael; Giamarellos-Bourboulis, Evangelos J; Dimopoulos, George; Brakhage, Axel A; Kniemeyer, Olaf

    2016-08-05

    During infection, the human pathogenic fungus Candida albicans undergoes a yeast-to-hypha transition, secretes numerous proteins for invasion of host tissues, and modulates the host's immune response. Little is known about the interplay of C. albicans secreted proteins and the host adaptive immune system. Here, we applied a combined 2D gel- and LC-MS/MS-based approach for the characterization of C. albicans extracellular proteins during the yeast-to-hypha transition, which led to a comprehensive C. albicans secretome map. The serological responses to C. albicans extracellular proteins were investigated by a 2D-immunoblotting approach combined with MS for protein identification. On the basis of the screening of sera from candidemia and three groups of noncandidemia patients, a core set of 19 immunodominant antibodies against secreted proteins of C. albicans was identified, seven of which represent potential diagnostic markers for candidemia (Xog1, Lip4, Asc1, Met6, Tsa1, Tpi1, and Prx1). Intriguingly, some secreted, strongly glycosylated protein antigens showed high cross-reactivity with sera from noncandidemia control groups. Enzymatic deglycosylation of proteins secreted from hyphae significantly impaired sera antibody recognition. Furthermore, deglycosylation of the recombinantly produced, secreted aspartyl protease Sap6 confirmed a significant contribution of glycan epitopes to the recognition of Sap6 by antibodies in patient's sera.

  18. Multiple strategies to prevent oxidative stress in Arabidopsis plants lacking the malate valve enzyme NADP-malate dehydrogenase

    Science.gov (United States)

    Hebbelmann, Inga; Selinski, Jennifer; Wehmeyer, Corinna; Goss, Tatjana; Voss, Ingo; Mulo, Paula; Kangasjärvi, Saijaliisa; Aro, Eva-Mari; Oelze, Marie-Luise; Dietz, Karl-Josef; Nunes-Nesi, Adriano; Do, Phuc T.; Fernie, Alisdair R.; Talla, Sai K.; Raghavendra, Agepati S.; Linke, Vera; Scheibe, Renate

    2012-01-01

    The nuclear-encoded chloroplast NADP-dependent malate dehydrogenase (NADP-MDH) is a key enzyme controlling the malate valve, to allow the indirect export of reducing equivalents. Arabidopsis thaliana (L.) Heynh. T-DNA insertion mutants of NADP-MDH were used to assess the role of the light-activated NADP-MDH in a typical C3 plant. Surprisingly, even when exposed to high-light conditions in short days, nadp-mdh knockout mutants were phenotypically indistinguishable from the wild type. The photosynthetic performance and typical antioxidative systems, such as the Beck–Halliwell–Asada pathway, were barely affected in the mutants in response to high-light treatment. The reactive oxygen species levels remained low, indicating the apparent absence of oxidative stress, in the mutants. Further analysis revealed a novel combination of compensatory mechanisms in order to maintain redox homeostasis in the nadp-mdh plants under high-light conditions, particularly an increase in the NTRC/2-Cys peroxiredoxin (Prx) system in chloroplasts. There were indications of adjustments in extra-chloroplastic components of photorespiration and proline levels, which all could dissipate excess reducing equivalents, sustain photosynthesis, and prevent photoinhibition in nadp-mdh knockout plants. Such metabolic flexibility suggests that the malate valve acts in concert with other NADPH-consuming reactions to maintain a balanced redox state during photosynthesis under high-light stress in wild-type plants. PMID:22140244

  19. Incorporation of Pr into LuAG ceramics

    Science.gov (United States)

    Marchewka, M. R.; Chapman, M. G.; Qian, H.; Jacobsohn, L. G.

    2017-06-01

    An investigation of the effects of Pr in (Lu1-xPrx)3Al5O12 (LuAG:Pr) ceramics was carried out by means of x-ray diffraction (XRD), energy dispersive x-ray spectroscopy (EDX), and attenuated total reflection Fourier transform infrared spectroscopy (ATR FTIR) measurements coupled with luminescence measurements. It was found that the Pr concentration that maximizes luminescence emission depends on the thermal processing conditions. While the calcined LuAG:Pr powder showed maximum luminescence emission for Pr concentrations between 0.18 and 0.33 at.%, maximum emission of ceramic bodies sintered at 1500 °C for 20 h was obtained with Pr concentrations between 0.018 and 0.18 at.%. Further, for short sintering times up to about 3 h, luminescence emission intensity is maximum for Pr concentrations around 0.33 at.%. Longer sintering times lead to the formation of PrAlO3 as a secondary phase, concomitant with a reduction of the intensity of luminescence emission.

  20. Caracterización morfoagronómica e isoenzimática de 23 accesiones de Leucaena spp. Morphoagronomic and isoenzymatic characterization of 23 Leucaena spp. accessions

    Directory of Open Access Journals (Sweden)

    Hilda B Wencomo

    2011-12-01

    Full Text Available El objetivo de este trabajo fue valorar el grado de diversidad existente en 23 accesiones de Leucaena, atendiendo a los caracteres morfoagronómicos e isoenzimáticos. Se incluyeron cinco especies de este género (L. leucocephala, L. lanceolata, L. diversifolia, L. macrophylla y L. esculenta, además de los cultivares comerciales. Se evaluó: la altura de la planta, el número de ramas, el grosor del tallo, el comportamiento de los patrones fenológicos de floración y fructificación, el número de pinnas por hoja y de pínulas por pinna, entre otros. Se realizaron además los análisis electroforéticos peroxidasas (Prx,α- y ß- esterasas (Est, malato deshidrogenasa (Mdh y alcohol deshidrogenasa (Adh. Las accesiones cumplieron con los criterios de selección predeterminados en cuanto a los caracteres morfoagronómicos, aunque no en el mismo tiempo. En este sentido, se destacaron L. leucocephala cv. Cunningham, cv. Perú, CIAT-9119, CIAT-9438, CIAT-751, CIAT-7988, CIAT-7384, CIAT-7929, CIAT-17480, cv. Ipil-Ipil y cv. CNIA-250; L. lanceolata CIAT-17255 y CIAT-17501, y L. diversifolia CIAT-17270. Se pudo detectar la existencia de variabilidad genética dentro de la colección. Los sistemas isoenzimáticos (esterasas y peroxidasas resultaron polimórficos en la muestra estudiada, principalmente las esterasas. Por otra parte, el análisis de diversidad genética permitió diferenciar L. leucocephala con una mayor claridad respecto al resto de las especies estudiadas, aunque no se ganó en discriminación dentro de la especie.The objective of this work was to evaluate the existing diversity degree in 23 Leucaena accessions, regarding the morphoagronomic and isoenzymatic characteristics. Five species of this genus were included (L. leucocephala, L. lanceolata, L. diversifolia, L. macrophylla and L. esculenta, in addition to the commercial cultivars. The following aspects were evaluated: plant height, number of branches, stem diameter, performance of

  1. Comparison of topological clustering within protein networks using edge metrics that evaluate full sequence, full structure, and active site microenvironment similarity.

    Science.gov (United States)

    Leuthaeuser, Janelle B; Knutson, Stacy T; Kumar, Kiran; Babbitt, Patricia C; Fetrow, Jacquelyn S

    2015-09-01

    The development of accurate protein function annotation methods has emerged as a major unsolved biological problem. Protein similarity networks, one approach to function annotation via annotation transfer, group proteins into similarity-based clusters. An underlying assumption is that the edge metric used to identify such clusters correlates with functional information. In this contribution, this assumption is evaluated by observing topologies in similarity networks using three different edge metrics: sequence (BLAST), structure (TM-Align), and active site similarity (active site profiling, implemented in DASP). Network topologies for four well-studied protein superfamilies (enolase, peroxiredoxin (Prx), glutathione transferase (GST), and crotonase) were compared with curated functional hierarchies and structure. As expected, network topology differs, depending on edge metric; comparison of topologies provides valuable information on structure/function relationships. Subnetworks based on active site similarity correlate with known functional hierarchies at a single edge threshold more often than sequence- or structure-based networks. Sequence- and structure-based networks are useful for identifying sequence and domain similarities and differences; therefore, it is important to consider the clustering goal before deciding appropriate edge metric. Further, conserved active site residues identified in enolase and GST active site subnetworks correspond with published functionally important residues. Extension of this analysis yields predictions of functionally determinant residues for GST subgroups. These results support the hypothesis that active site similarity-based networks reveal clusters that share functional details and lay the foundation for capturing functionally relevant hierarchies using an approach that is both automatable and can deliver greater precision in function annotation than current similarity-based methods. © 2015 The Authors Protein Science

  2. The genetics and conservation of Araucaria angustifolia: I. Genetic structure and diversity of natural populations by means of non-adaptive variation in the state of Santa Catarina, Brazil

    Directory of Open Access Journals (Sweden)

    Neiva Maria Frizon Auler

    2002-01-01

    Full Text Available The objective of this study was to generate information relative to the allele distribution and dynamics within and among populations of Araucaria angustifolia, a naturally-occurring conifer in the south of Brazil, being known popularly as "pinheiro-do-Paraná", "araucaria" or pine tree. In order to elucidate the levels and the distribution of the genetic variability, the population's genetic structure and the genetic distance among natural populations of this species with different levels of disturbance in different geographical areas were studied in detail. For this, samples of leaf tissue were collected from 328 adult individuals in nine natural populations in Santa Catarina State. To analyze the samples, the allozyme technique was applied in starch gel electrophoresis (penetrose 13%, with citrate/morfholine buffer. Nine enzymatic systems (PGM, PGI MDH, PRX, SKDH, 6PGDH, ACP, IDH and G6PDH revealed 15 loci. The analysis provided values for He and Ho of 0.084 and 0.072, respectively. The general average of polymorphic loci was 73% in the species and 26.6% in the studied populations and the allele number per locus was 1.6. Wright's F-statistical estimates indicated the existence of inbreeding in populations (F IS= 0.148 and a low divergence among populations (F ST = 0.044. However, the inbreeding values were variable in different populations. Taken together, the results indicated that the greater part of the genetic variability is contained within populations. The working hypothesis that originally there was greater genetic diversity can be supported by these results which indicate that in the degraded populations the diversity indexes are lower in the degraded populations than those found in better-conserved populations. Thus the fragmentation of the forest followed by "araucaria" exploitation could have contributed to the genetic differentiation expressed through the allele frequency of the studied population.

  3. Vitamin D: calcium and bone homeostasis during evolution

    Science.gov (United States)

    Bouillon, Roger; Suda, Tatsuo

    2014-01-01

    Vitamin D3 is already found early in the evolution of life but essentially as inactive end products of the photochemical reaction of 7-dehydrocholestol with ultraviolet light B. A full vitamin D (refers to vitamin D2 and D3) endocrine system, characterized by a specific VDR (vitamin D receptor, member of the nuclear receptor family), specific vitamin D metabolizing CYP450 enzymes regulated by calciotropic hormones and a dedicated plasma transport-protein is only found in vertebrates. In the earliest vertebrates (lamprey), vitamin D metabolism and VDR may well have originated from a duplication of a common PRX/VDR ancestor gene as part of a xenobiotic detoxification pathway. The vitamin D endocrine system, however, subsequently became an important regulator of calcium supply for an extensive calcified skeleton. Vitamin D is essential for normal calcium and bone homeostasis as shown by rickets in vitamin D-deficient growing amphibians, reptiles, birds and mammals. From amphibians onward, bone is gradually more dynamic with regulated bone resorption, mainly by combined action of PTH and 1α,25-dihydroxyvitamin D3 (1,25(OH)2D3) on the generation and function of multinucleated osteoclasts. Therefore, bone functions as a large internal calcium reservoir, under the control of osteoclasts. Osteocytes also display a remarkable spectrum of activities, including mechanical sensing and regulating mineral homeostasis, but also have an important role in global nutritional and energy homeostasis. Mineralization from reptiles onward is under the control of well-regulated SIBLING proteins and associated enzymes, nearly all under the control of 1,25(OH)2D3. The vitamin D story thus started as inert molecule but gained an essential role for calcium and bone homeostasis in terrestrial animals to cope with the challenge of higher gravity and calcium-poor environment. PMID:24466411

  4. Garlic revisited: antimicrobial activity of allicin-containing garlic extracts against Burkholderia cepacia complex.

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    Daynea Wallock-Richards

    Full Text Available The antimicrobial activities of garlic and other plant alliums are primarily based on allicin, a thiosulphinate present in crushed garlic bulbs. We set out to determine if pure allicin and aqueous garlic extracts (AGE exhibit antimicrobial properties against the Burkholderia cepacia complex (Bcc, the major bacterial phytopathogen for alliums and an intrinsically multiresistant and life-threatening human pathogen. We prepared an AGE from commercial garlic bulbs and used HPLC to quantify the amount of allicin therein using an aqueous allicin standard (AAS. Initially we determined the minimum inhibitory concentrations (MICs of the AGE against 38 Bcc isolates; these MICs ranged from 0.5 to 3% (v/v. The antimicrobial activity of pure allicin (AAS was confirmed by MIC and minimum bactericidal concentration (MBC assays against a smaller panel of five Bcc isolates; these included three representative strains of the most clinically important species, B. cenocepacia. Time kill assays, in the presence of ten times MIC, showed that the bactericidal activity of AGE and AAS against B. cenocepacia C6433 correlated with the concentration of allicin. We also used protein mass spectrometry analysis to begin to investigate the possible molecular mechanisms of allicin with a recombinant form of a thiol-dependent peroxiredoxin (BCP, Prx from B. cenocepacia. This revealed that AAS and AGE modifies an essential BCP catalytic cysteine residue and suggests a role for allicin as a general electrophilic reagent that targets protein thiols. To our knowledge, we report the first evidence that allicin and allicin-containing garlic extracts possess inhibitory and bactericidal activities against the Bcc. Present therapeutic options against these life-threatening pathogens are limited; thus, allicin-containing compounds merit investigation as adjuncts to existing antibiotics.

  5. Garlic revisited: antimicrobial activity of allicin-containing garlic extracts against Burkholderia cepacia complex.

    Science.gov (United States)

    Wallock-Richards, Daynea; Doherty, Catherine J; Doherty, Lynsey; Clarke, David J; Place, Marc; Govan, John R W; Campopiano, Dominic J

    2014-01-01

    The antimicrobial activities of garlic and other plant alliums are primarily based on allicin, a thiosulphinate present in crushed garlic bulbs. We set out to determine if pure allicin and aqueous garlic extracts (AGE) exhibit antimicrobial properties against the Burkholderia cepacia complex (Bcc), the major bacterial phytopathogen for alliums and an intrinsically multiresistant and life-threatening human pathogen. We prepared an AGE from commercial garlic bulbs and used HPLC to quantify the amount of allicin therein using an aqueous allicin standard (AAS). Initially we determined the minimum inhibitory concentrations (MICs) of the AGE against 38 Bcc isolates; these MICs ranged from 0.5 to 3% (v/v). The antimicrobial activity of pure allicin (AAS) was confirmed by MIC and minimum bactericidal concentration (MBC) assays against a smaller panel of five Bcc isolates; these included three representative strains of the most clinically important species, B. cenocepacia. Time kill assays, in the presence of ten times MIC, showed that the bactericidal activity of AGE and AAS against B. cenocepacia C6433 correlated with the concentration of allicin. We also used protein mass spectrometry analysis to begin to investigate the possible molecular mechanisms of allicin with a recombinant form of a thiol-dependent peroxiredoxin (BCP, Prx) from B. cenocepacia. This revealed that AAS and AGE modifies an essential BCP catalytic cysteine residue and suggests a role for allicin as a general electrophilic reagent that targets protein thiols. To our knowledge, we report the first evidence that allicin and allicin-containing garlic extracts possess inhibitory and bactericidal activities against the Bcc. Present therapeutic options against these life-threatening pathogens are limited; thus, allicin-containing compounds merit investigation as adjuncts to existing antibiotics.

  6. Molecular analysis of the genes causing recessive demyelinating Charcot-Marie-Tooth disease in Japan.

    Science.gov (United States)

    Hayashi, Makiko; Abe, Akiko; Murakami, Tatsufumi; Yamao, Satoshi; Arai, Hidee; Hattori, Hideji; Iai, Mizue; Watanabe, Kyoko; Oka, Nobuyuki; Chida, Keiji; Kishikawa, Yumiko; Hayasaka, Kiyoshi

    2013-05-01

    Charcot-Marie-Tooth disease (CMT), the most common hereditary neuropathy, has been classified into two types, demyelinating and axonal types. We previously analyzed the genes causing dominant demyelinating CMT in 227 Japanese patients to identify the genetic background, but could not find any mutations in 110 patients. To investigate the frequency of patients with autosomal recessive demyelinating CMT (CMT4) mutations, we analyzed the coding sequence of known causative genes of CMT4 in 103 demyelinating CMT patients, excluding seven patients owing to lack of specimens. We found one patient with a GDAP1 mutation, one patient with an MTMR2 mutation, two patients with SH3TC2/KIAA1985 mutations and three patients with FGD4 mutations. Twelve patients, including five previously detected patients with PRX mutations, were diagnosed as CMT4, accounting for 5.5% of demyelinating CMT. In the patient with GDAP1 mutation, only one mutation inherited from his mother was detected by genomic sequencing. Analysis by reverse transcription polymerase chain reaction using messenger RNA (mRNA) from the patient's leukocytes revealed the absence of transcription from the allele inherited from his father, suggesting the existence of one more mutation leading to a lack or destabilization of mRNA. Most patients carrying CMT4 gene mutations present with early-onset and slowly progressive symptoms, which may be associated with the function of mutants. We could not identify the disease-causing gene in 96 patients (about 45%). Further studies including studies with next-generation sequencers will be required to identify the causative gene in Japanese CMT.

  7. GATA6 Is a Crucial Regulator of Shh in the Limb Bud

    Science.gov (United States)

    Kozhemyakina, Elena; Ionescu, Andreia; Lassar, Andrew B.

    2014-01-01

    In the limb bud, patterning along the anterior-posterior (A-P) axis is controlled by Sonic Hedgehog (Shh), a signaling molecule secreted by the “Zone of Polarizing Activity”, an organizer tissue located in the posterior margin of the limb bud. We have found that the transcription factors GATA4 and GATA6, which are key regulators of cell identity, are expressed in an anterior to posterior gradient in the early limb bud, raising the possibility that GATA transcription factors may play an additional role in patterning this tissue. While both GATA4 and GATA6 are expressed in an A-P gradient in the forelimb buds, the hindlimb buds principally express GATA6 in an A-P gradient. Thus, to specifically examine the role of GATA6 in limb patterning we generated Prx1-Cre; GATA6fl/fl mice, which conditionally delete GATA6 from their developing limb buds. We found that these animals display ectopic expression of both Shh and its transcriptional targets specifically in the anterior mesenchyme of the hindlimb buds. Loss of GATA6 in the developing limbs results in the formation of preaxial polydactyly in the hindlimbs. Conversely, forced expression of GATA6 throughout the limb bud represses expression of Shh and results in hypomorphic limbs. We have found that GATA6 can bind to chromatin (isolated from limb buds) encoding either Shh or Gli1 regulatory elements that drive expression of these genes in this tissue, and demonstrated that GATA6 works synergistically with FOG co-factors to repress expression of luciferase reporters driven by these sequences. Most significantly, we have found that conditional loss of Shh in limb buds lacking GATA6 prevents development of hindlimb polydactyly in these compound mutant embryos, indicating that GATA6 expression in the anterior region of the limb bud blocks hindlimb polydactyly by repressing ectopic expression of Shh. PMID:24415953

  8. GATA6 is a crucial regulator of Shh in the limb bud.

    Directory of Open Access Journals (Sweden)

    Elena Kozhemyakina

    2014-01-01

    Full Text Available In the limb bud, patterning along the anterior-posterior (A-P axis is controlled by Sonic Hedgehog (Shh, a signaling molecule secreted by the "Zone of Polarizing Activity", an organizer tissue located in the posterior margin of the limb bud. We have found that the transcription factors GATA4 and GATA6, which are key regulators of cell identity, are expressed in an anterior to posterior gradient in the early limb bud, raising the possibility that GATA transcription factors may play an additional role in patterning this tissue. While both GATA4 and GATA6 are expressed in an A-P gradient in the forelimb buds, the hindlimb buds principally express GATA6 in an A-P gradient. Thus, to specifically examine the role of GATA6 in limb patterning we generated Prx1-Cre; GATA6(fl/fl mice, which conditionally delete GATA6 from their developing limb buds. We found that these animals display ectopic expression of both Shh and its transcriptional targets specifically in the anterior mesenchyme of the hindlimb buds. Loss of GATA6 in the developing limbs results in the formation of preaxial polydactyly in the hindlimbs. Conversely, forced expression of GATA6 throughout the limb bud represses expression of Shh and results in hypomorphic limbs. We have found that GATA6 can bind to chromatin (isolated from limb buds encoding either Shh or Gli1 regulatory elements that drive expression of these genes in this tissue, and demonstrated that GATA6 works synergistically with FOG co-factors to repress expression of luciferase reporters driven by these sequences. Most significantly, we have found that conditional loss of Shh in limb buds lacking GATA6 prevents development of hindlimb polydactyly in these compound mutant embryos, indicating that GATA6 expression in the anterior region of the limb bud blocks hindlimb polydactyly by repressing ectopic expression of Shh.

  9. Oxygen vacancy induced room temperature ferromagnetism in Pr-doped CeO2 thin films on silicon.

    Science.gov (United States)

    Niu, Gang; Hildebrandt, Erwin; Schubert, Markus Andreas; Boscherini, Federico; Zoellner, Marvin Hartwig; Alff, Lambert; Walczyk, Damian; Zaumseil, Peter; Costina, Ioan; Wilkens, Henrik; Schroeder, Thomas

    2014-10-22

    Integration of functional oxides on Si substrates could open a pathway to integrate diverse devices on Si-based technology. Oxygen vacancies (Vo(··)) can strongly affect solid state properties of oxides, including the room temperature ferromagnetism (RTFM) in diluted magnetic oxides. Here, we report a systematical study on the RTFM of oxygen vacancy engineered (by Pr(3+) doping) CeO2 epitaxial thin films on Si substrates. High quality, mixed single crystalline Ce1-xPrxO2-δ (x = 0-1) solid solution films were obtained. The Ce ions in CeO2 with a fluorite structure show a Ce(4+)-dominant valence state in all films. The local crystal structures of the films were analyzed in detail. Pr doping creates both Vo(··) and PrO8-complex defects in CeO2 and their relative concentrations vary with the Pr-doping level. The RTFM properties of the films reveal a strong dependence on the relative Vo(··) concentration. The RTFM in the films initially increases with higher Pr-doping levels due to the increase of the F(+) center (Vo(··) with one occupied electron) concentration and completely disappears when x > 0.2, where the magnetic polaron concentration is considered to decline below the percolation threshold, thus long-range FM order can no longer be established. We thus demonstrate the possibility to directly grow RTFM Pr-doped CeO2 films on Si substrates, which can be an interesting candidate for potential magneto-optic or spintronic device applications.

  10. A cell wall-bound anionic peroxidase, PtrPO21, is involved in lignin polymerization in Populus trichocarpa

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Chien-Yuan; Li, Quanzi; Tunlaya-Anukit, Sermsawat; Shi, Rui; Sun, Ying-Hsuan; Wang, Jack P.; Liu, Jie; Loziuk, Philip; Edmunds, Charles W.; Miller, Zachary D.; Peszlen, Ilona; Muddiman, David C.; Sederoff, Ronald R.; Chiang, Vincent L.

    2016-03-11

    Class III peroxidases are members of a large plant-specific sequence-heterogeneous protein family. Several sequence-conserved homologs have been associated with lignin polymerization in Arabidopsis thaliana, Oryza sativa, Nicotiana tabacum, Zinnia elegans, Picea abies, and Pinus sylvestris. In Populus trichocarpa, a model species for studies of wood formation, the peroxidases involved in lignin biosynthesis have not yet been identified. To do this, we retrieved sequences of all PtrPOs from Peroxibase and conducted RNA-seq to identify candidates. Transcripts from 42 PtrPOs were detected in stem differentiating xylem (SDX) and four of them are the most xylem-abundant (PtrPO12, PtrPO21, PtrPO42, and PtrPO64). PtrPO21 shows xylem-specific expression similar to that of genes encoding the monolignol biosynthetic enzymes. Using protein cleavage-isotope dilution mass spectrometry, PtrPO21 is detected only in the cell wall fraction and not in the soluble fraction. Downregulated transgenics of PtrPO21 have a lignin reduction of ~20% with subunit composition (S/G ratio) similar to wild type. The transgenics show a growth reduction and reddish color of stem wood. The modulus of elasticity (MOE) of the stems of the downregulated PtrPO21-line 8 can be reduced to ~60% of wild type. Differentially expressed gene (DEG) analysis of PtrPO21 downregulated transgenics identified a significant overexpression of PtPrx35, suggesting a compensatory effect within the peroxidase family. No significant changes in the expression of the 49 P. trichocarpa laccases (PtrLACs) were observed.

  11. Role of abscisic acid (ABA) in activating antioxidant tolerance responses to desiccation stress in intertidal seaweed species.

    Science.gov (United States)

    Guajardo, Eduardo; Correa, Juan A; Contreras-Porcia, Loretto

    2016-03-01

    The hormone ABA regulates the oxidative stress state under desiccation in seaweed species; an environmental condition generated during daily tidal changes. Desiccation is one of the most important factors that determine the distribution pattern of intertidal seaweeds. Among most tolerant seaweed is Pyropia orbicularis, which colonizes upper intertidal zones along the Chilean coast. P. orbicularis employs diverse mechanisms of desiccation tolerance (DT) (among others, e.g., antioxidant activation, photoinhibition, and osmo-compatible solute overproduction) such as those used by resurrection plants and bryophytes. In these organisms, the hormone abscisic acid (ABA) plays an important role in regulating responses to water deficit, including gene expression and the activity of antioxidant enzymes. The present study determined the effect of ABA on the activation of antioxidant responses during desiccation in P. orbicularis and in the sensitive species Mazzaella laminarioides and Lessonia spicata. Changes in endogenous free and conjugated ABA, water content during the hydration-desiccation cycle, enzymatic antioxidant activities [ascorbate peroxidase (AP), catalase (CAT) and peroxiredoxine (PRX)], and levels of lipid peroxidation and cell viability were evaluated. The results showed that P. orbicularis had free ABA levels 4-7 times higher than sensitive species, which was overproduced during water deficit. Using two ABA inhibitors (sodium tungstate and ancymidol), ABA was found to regulate the activation of the antioxidant enzymes activities during desiccation. In individuals exposed to exogenous ABA the enzyme activity increased, concomitant with low lipid peroxidation and high cell viability. These results demonstrate the participation of ABA in the regulation of DT in seaweeds, and suggest that regulatory mechanisms with ABA signaling could be of great importance for the adaptation of these organisms to dehydration.

  12. Inhibition of CaMKK2 Enhances Fracture Healing by Stimulating Indian Hedgehog Signaling and Accelerating Endochondral Ossification.

    Science.gov (United States)

    Williams, Justin N; Kambrath, Anuradha Valiya; Patel, Roshni B; Kang, Kyung Shin; Mével, Elsa; Li, Yong; Cheng, Ying-Hua; Pucylowski, Austin J; Hassert, Mariah A; Voor, Michael J; Kacena, Melissa A; Thompson, William R; Warden, Stuart J; Burr, David B; Allen, Matthew R; Robling, Alexander G; Sankar, Uma

    2018-01-03

    Approximately ten percent of all bone fractures do not heal, resulting in patient morbidity and healthcare costs. However, no pharmacological treatments are currently available to promote efficient bone healing. Inhibition of Ca2+ /calmodulin (CaM)-dependent protein kinase kinase 2 (CaMKK2) reverses age-associated loss of trabecular and cortical bone volume and strength in mice. In the current study, we investigated the role of CaMKK2 in bone fracture healing and show that its pharmacological inhibition using STO-609 accelerates early cellular and molecular events associated with endochondral ossification, resulting in a more rapid and efficient healing of the fracture. Within 7 days post-fracture, treatment with STO-609 resulted in enhanced Indian hedgehog signaling, paired-related homeobox (PRX1)-positive mesenchymal stem cell recruitment, chondrocyte differentiation and hypertrophy, along with elevated expression of osterix, vascular endothelial growth factor and type 1 collagen at the fracture callus. Early deposition of primary bone by osteoblasts resulted in STO-609 treated mice possessing significantly higher callus bone volume by 14 days following fracture. Subsequent rapid maturation of the bone matrix bestowed fractured bones in STO-609 treated animals with significantly higher torsional strength and stiffness by 28 days post-injury, indicating accelerated healing of the fracture. Previous studies indicate that fixed and closed femoral fractures in the mice take 35 days to fully heal without treatment. Therefore, our data suggest that STO-609 potentiates a 20% acceleration of the bone healing process. Moreover, inhibiting CaMKK2 also imparted higher mechanical strength and stiffness at the contralateral cortical bone within 4 weeks of treatment. Taken together, the data presented here underscore the therapeutic potential of targeting CaMKK2 to promote efficacious and rapid healing of bone fractures and as a mechanism to strengthen normal bones. This

  13. The Pr and Ca Substitution in GdBa2Cu3O7- & delta

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    H. S. H.

    2001-12-01

    Full Text Available   The granular Gd1-x-zPrxCazBa2Cu3O7-δ high-temperature cuprate samples with 0.0 ≤ x ≤ 0.3 and 0.0≤ x ≤ 0.35 are prepared by standard solid state reaction and characterized by XRD and SEM techniques. The BaCuO2 and impurity phases are less than 1% in the samples having high levels of pr and Ca concentrations. The electrical resistivity measurements show a nonlinear reduction in Tc(x,z=etc versus x. Moreover, the Tc(z curve with x=0 is nonlinear and aplateau appears at z≈ 0.05-0.015. For Pr-Ca-doped samples with a constant concentration of Pr, Tc increases with the increase of Ca up to an optimum value of Ca doping and then in decreases. Based on these observations, we suggest that hole filling and hole localization the main effects of Pr ion substiution. The magnetic measurements indicate that the value of Hc1 is in the order of 10 mT. The mangetoresistance measurements have been measured and analyzed. The superconducting transition region is broadened by the application of magnetic field. The experimental data near the onsen of superconductivity are fitted with the Ambegakor and Halperin (AH phase-slip model. We observe that the AH parameter,γ (H, depends not only on the temperature and the magnetic field, but also on the Pr and Ca ions concentrations. It is observed that the critical current density increases with Ca substitution and decreases with Pr substitution in Gd-123 system. We suggest that the Pr ion substitution probably enhances the weak link, but the Ca ion acts as flux pinning center in the GdPrCa-123 system.

  14. Oxidative Stress in Horseradish (Armoracia lapathifolia Gilib. Tissues Grown in vitro

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    Petra Peharec

    2011-01-01

    Full Text Available In a previous study it was reported that transformed tissue of horseradish (Armoracia lapathifolia Gilib., obtained by infection of leaf explants with A. tumefaciens, developed two tumour lines with different morphology. One line grew as a completely unorganized tissue (TN – tumour tissue, while the other line grew as a partially organized teratogenous tumour with malformed hyperhydric shoots (TM – teratoma tissue, but did not regenerate the whole plant of normal morphology. The factor responsible for this problem could be the increased production of reactive oxygen species (ROS. Therefore, in this study a possible involvement of activated oxygen metabolism in dedifferentiation and hyperhydricity in TM and TN tissues is investigated. Elevated values of malondialdehyde and protein carbonyl contents found in TM and TN, in comparison with plantlet leaf, confirm the presence of oxidative stress. However, lower H2O2 content was measured in TM and TN. Lipoxygenase (LOX activity was more pronounced in TM and especially in TN compared to leaf, which suggests that the LOX-dependent peroxidation of fatty acids might be one of the causes of oxidative damage. Moreover, significantly higher peroxidase (PRX and ascorbate peroxidase (APX activity as well as the increased number of their isoforms was found in transformed TM and TN in comparison with leaf. On the other hand, significantly lower superoxide dismutase (SOD activity was found in TM and TN, which correlates with lower H2O2 content. High catalase (CAT activity measured in leaf and partially organized TM is consistent with the role of CAT in growth and differentiation. In conclusion, in horseradish transformed tissues that underwent dedifferentiation and hyperhydricity, prominent oxidative damage was found. This result suggests that oxidative stress could be associated with the inability of partially organized teratogenous TM to regenerate plantlets with normal morphology.

  15. Distribution of extreme rainfall events over Ebro River basin

    Science.gov (United States)

    Saa, Antonio; Tarquis, Ana Maria; Valencia, Jose Luis; Gascó, Jose Maria

    2010-05-01

    The purpose of this work is to provide a description of the heavy rainfall phenomenon on statistical tools from a Spanish region. We want to quantify the effect of the climate change to verify the rapidity of its evolution across the variation of the probability distributions. Our conclusions have special interest for the agrarian insurances, which may make estimates of costs more realistically. In this work, the analysis mainly focuses on: The distribution of consecutive days without rain for each gauge stations and season. We estimate density Kernel functions and Generalized Pareto Distribution (GPD) for a network of station from the Ebro River basin until a threshold value u. We can establish a relation between distributional parameters and regional characteristics. Moreover we analyze especially the tail of the probability distribution. These tails are governed by law of power means that the number of events n can be expressed as the power of another quantity x : n(x) = x? . ? can be estimated as the slope of log-log plot the number of events and the size. The most convenient way to analyze n(x) is using the empirical probability distribution. Pr(X > x) ∞ x-?. The distribution of rainfall over percentile of order 0.95 from wet days at the seasonal scale and in a yearly scale with the same treatment of tails than in the previous section. The evolution of the distribution in the second XXth century and the impact on the extreme values model. After realized the analyses it does not appreciate difference in the distribution throughout the time which suggests that this region does not appreciate increase of the extreme values both for the number of dry consecutive days and for the value of the rainfall References: Coles, Stuart (2001). An Introduction to Statistical Modeling of Extreme Values,. Springer-Verlag Krishnamoorthy K. (2006), Handbook of Statistical Distributions with Applications, Chapman & Hall/CRC. Bodini A., Cossu A. (2010). Vulnerability assessment

  16. Transcranial Doppler Systolic Flow Index and ICP-Derived Cerebrovascular Reactivity Indices in Traumatic Brain Injury.

    Science.gov (United States)

    Zeiler, Frederick A; Cardim, Danilo; Donnelly, Joseph; Menon, David K; Czosnyka, Marek; Smielewski, Peter

    2017-12-18

    The purpose of our study was to explore relationships between transcranial Doppler (TCD) indices of cerebrovascular reactivity and those derived from intracranial pressure (ICP). Goals included: A) confirming previously described co-variance patterns of TCD/ICP indices, and B) describing thresholds for systolic flow index (Sx; correlation between systolic flow velocity [FVs] and cerebral perfusion pressure [CPP]) associated with outcome. In a retrospective cohort of traumatic brain injury (TBI) patients: with TCD and ICP monitoring, we calculated various continuous indices of cerebrovascular reactivity: A) ICP (pressure reactivity index [PRx]: correlation between ICP and mean arterial pressure [MAP]; PAx: correlation between pulse amplitude of ICP [AMP] and MAP; RAC: correlation between AMP and CPP) and B) TCD (mean flow index [Mx]: correlation between mean flow velocity [FVm] and CPP; Mx_a: correlation between FVm and MAP; Sx: correlation between FVs and CPP; Sx_a: correlation between FVs and MAP; Dx: correlation between diastolic flow velocity [FVd] and CPP; Dx_a: correlation between FVd and MAP). We assessed the relationships via various statistical techniques, including: principal component analysis, agglomerative hierarchal clustering, and k-means cluster analysis (KMCA). We performed sequential χ2 testing to define thresholds associated with outcome for Sx/Sx_a. Outcome was assessed at 6 months via dichotomized Glasgow Outcome Score (GOS): A) Favorable (GOS 4 or 5) versus Unfavorable (GOS 3 or less), B) Alive versus Dead. We analyzed 410 recordings in 347 patients. All analyses confirmed our previously described co-variance of Sx/Sx_a with ICP-derived indices. Sx displayed thresholds of -0.15 for unfavorable outcome (p < 0.0001) and -0.20 for mortality (p < 0.0001). Sx_a displayed thresholds of +0.05 (p = 0.019) and -0.10 (p = 0.0001) for alive/dead and favorable/unfavorable outcomes. TCD systolic indices are most closely associated with ICP

  17. RNA-seq Transcriptome Response of Flax (Linum usitatissimum L. to the Pathogenic Fungus Fusarium oxysporum f. sp. lini.

    Directory of Open Access Journals (Sweden)

    Leonardo Miguel Galindo-González

    2016-11-01

    -related enzymes chalcone synthase, dihydroflavonol reductase and multiple anthocyanidin synthases; and a peroxidase implicated in lignin formation (PRX52. Additionally, regulation of some genes indicated potential pathogen manipulation to facilitate infection; these included four disease resistance proteins that were repressed, indole acetic acid amido/amino hydrolases which were upregulated, activated expansins and glucanases, amino acid transporters and aquaporins, and finally, repression of major latex proteins.

  18. Dual neuroprotective pathways of a pro-electrophilic compound via HSF-1-activated heat-shock proteins and Nrf2-activated phase 2 antioxidant response enzymes.

    Science.gov (United States)

    Satoh, Takumi; Rezaie, Tayebeh; Seki, Masaaki; Sunico, Carmen R; Tabuchi, Takahito; Kitagawa, Tomomi; Yanagitai, Mika; Senzaki, Mutsumi; Kosegawa, Chihiro; Taira, Hideharu; McKercher, Scott R; Hoffman, Jennifer K; Roth, Gregory P; Lipton, Stuart A

    2011-11-01

    Activation of the Keap1/nuclear factor erythroid 2-related factor 2 (Nrf2) pathway and consequent induction of phase 2 antioxidant enzymes is known to afford neuroprotection. Here, we present a series of novel electrophilic compounds that protect neurons via this pathway. Natural products, such as carnosic acid (CA), are present in high amounts in the herbs rosemary and sage as ortho-dihydroquinones, and have attracted particular attention because they are converted by oxidative stress to their active form (ortho-quinone species) that stimulate the Keap1/Nrf2 transcriptional pathway. Once activated, this pathway leads to the production of a series of antioxidant phase 2 enzymes. Thus, such dihydroquinones function as redox-activated 'pro-electrophiles'. Here, we explored the concept that related para-dihydroquinones represent even more effective bioactive pro-electrophiles for the induction of phase 2 enzymes without producing toxic side effects. We synthesized several novel para-hydroquinone-type pro-electrophilic compounds (designated D1 and D2) to analyze their protective mechanism. DNA microarray, PCR, and western blot analyses showed that compound D1 induced expression of heat-shock proteins (HSPs), including HSP70, HSP27, and DnaJ, in addition to phase 2 enzymes such as hemeoxygenase-1 (HO-1), NADP(H) quinine-oxidoreductase1, and the Na(+)-independent cystine/glutamate exchanger (xCT). Treatment with D1 resulted in activation of Nrf2 and heat-shock transcription factor-1 (HSF-1) transcriptional elements, thus inducing phase 2 enzymes and HSPs, respectively. In this manner, D1 protected neuronal cells from both oxidative and endoplasmic reticulum (ER)-related stress. Additionally, D1 suppressed induction of 78 kDa glucose-regulated protein (GRP78), an ER chaperone protein, and inhibited hyperoxidation of peroxiredoxin 2 (PRX2), a molecule that is in its reduced state can protect from oxidative stress. These results suggest that D1 is a novel pro

  19. Molecular Cloning of a cDNA Encoding for Taenia solium TATA-Box Binding Protein 1 (TsTBP1 and Study of Its Interactions with the TATA-Box of Actin 5 and Typical 2-Cys Peroxiredoxin Genes.

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    Oscar Rodríguez-Lima

    Full Text Available TATA-box binding protein (TBP is an essential regulatory transcription factor for the TATA-box and TATA-box-less gene promoters. We report the cloning and characterization of a full-length cDNA that encodes a Taenia solium TATA-box binding protein 1 (TsTBP1. Deduced amino acid composition from its nucleotide sequence revealed that encodes a protein of 238 residues with a predicted molecular weight of 26.7 kDa, and a theoretical pI of 10.6. The NH2-terminal domain shows no conservation when compared with to pig and human TBP1s. However, it shows high conservation in size and amino acid identity with taeniids TBP1s. In contrast, the TsTBP1 COOH-terminal domain is highly conserved among organisms, and contains the amino acids involved in interactions with the TATA-box, as well as with TFIIA and TFIIB. In silico TsTBP1 modeling reveals that the COOH-terminal domain forms the classical saddle structure of the TBP family, with one α-helix at the end, not present in pig and human. Native TsTBP1 was detected in T. solium cysticerci´s nuclear extract by western blot using rabbit antibodies generated against two synthetic peptides located in the NH2 and COOH-terminal domains of TsTBP1. These antibodies, through immunofluorescence technique, identified the TBP1 in the nucleus of cells that form the bladder wall of cysticerci of Taenia crassiceps, an organism close related to T. solium. Electrophoretic mobility shift assays using nuclear extracts from T. solium cysticerci and antibodies against the NH2-terminal domain of TsTBP1 showed the interaction of native TsTBP1 with the TATA-box present in T. solium actin 5 (pAT5 and 2-Cys peroxiredoxin (Ts2-CysPrx gene promoters; in contrast, when antibodies against the anti-COOH-terminal domain of TsTBP1 were used, they inhibited the binding of TsTBP1 to the TATA-box of the pAT5 promoter gene.

  20. Variabilidade genética em batata-doce com base em marcadores isoenzimáticos

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    Oliveira Antonio Carlos B. de

    2002-01-01

    Full Text Available A variabilidade genética de 55 clones de batata-doce, compreendendo cultivares comerciais e acessos obtidos de coletas, foi avaliada por meio de padrões isoenzimáticos, utilizando-se técnicas de análise multivariada. Cultivou-se uma planta por vaso, com 2 litros de capacidade, preenchido com terra, esterco e areia lavada na proporção de 3:2:1, com três repetições. As coletas das folhas e raízes novas para análises iniciaram-se aos 45 dias após o plantio. Foram utilizados, para folhas, os sistemas enzimáticos: GOT, alfaEST, betaEST, PGI, PGM e IDH e, para as raízes: PRX, alfaEST, betaEST, PGI, PGM e IDH. A combinação dos diferentes padrões enzimáticos e tecidos analisados possibilitou a discriminação individual de 32 dos 55 clones analisados. Os 23 clones restantes foram incluídos em sete grupos distintos, com base nos fenótipos isoenzimáticos exibidos. Os clones, dentro de cada um desses grupos, foram considerados materiais de mesmo genótipo, devido, também, às suas características morfológicas semelhantes. A aEST de raízes foi o sistema que apresentou maior número de bandas polimórficas, proporcionando a discriminação individual de 32 clones. O método de agrupamento de Tocher reuniu os 39 clones em nove grupos e, a análise pelo método das médias das distâncias, revelou a formação de onze grupos de similaridade. O clone 46 formou um grupo individual pelo método de Tocher e foi o mais divergente pelo método das médias das distâncias. Por apresentar boas características comerciais e produtivas, seria um dos clones eleitos para se iniciar programas de cruzamentos.

  1. Comparative molecular modeling study of Arabidopsis NADPH-dependent thioredoxin reductase and its hybrid protein.

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    Yuno Lee

    Full Text Available 2-Cys peroxiredoxins (Prxs play important roles in the protection of chloroplast proteins from oxidative damage. Arabidopsis NADPH-dependent thioredoxin reductase isotype C (AtNTRC was identified as efficient electron donor for chloroplastic 2-Cys Prx-A. There are three isotypes (A, B, and C of thioredoxin reductase (TrxR in Arabidopsis. AtNTRA contains only TrxR domain, but AtNTRC consists of N-terminal TrxR and C-terminal thioredoxin (Trx domains. AtNTRC has various oligomer structures, and Trx domain is important for chaperone activity. Our previous experimental study has reported that the hybrid protein (AtNTRA-(Trx-D, which was a fusion of AtNTRA and Trx domain from AtNTRC, has formed variety of structures and shown strong chaperone activity. But, electron transfer mechanism was not detected at all. To find out the reason of this problem with structural basis, we performed two different molecular dynamics (MD simulations on AtNTRC and AtNTRA-(Trx-D proteins with same cofactors such as NADPH and flavin adenine dinucleotide (FAD for 50 ns. Structural difference has found from superimposition of two structures that were taken relatively close to average structure. The main reason that AtNTRA-(Trx-D cannot transfer the electron from TrxR domain to Trx domain is due to the difference of key catalytic residues in active site. The long distance between TrxR C153 and disulfide bond of Trx C387-C390 has been observed in AtNTRA-(Trx-D because of following reasons: i unstable and unfavorable interaction of the linker region, ii shifted Trx domain, and iii different or weak interface interaction of Trx domains. This study is one of the good examples for understanding the relationship between structure formation and reaction activity in hybrid protein. In addition, this study would be helpful for further study on the mechanism of electron transfer reaction in NADPH-dependent thioredoxin reductase proteins.

  2. Cytoplasmic- and extracellular-proteome analysis of Diplodia seriata: a phytopathogenic fungus involved in grapevine decline

    Science.gov (United States)

    2010-01-01

    the identified proteins have been reported as pathogenicity factors in other phytopathogenic fungi. Moreover, this proteomic analysis supposes a useful basis for deepening into D. seriata knowledge and will contribute to the development of the molecular biology of this fungal strain as it has been demonstrated by cloning the gene Prx1 encoding mitochondrial peroxiredoxin-1 of D. seriata (the first gene to be cloned in this microorganism; data not shown). PMID:20828386

  3. Rictor is required for optimal bone accrual in response to anti-sclerostin therapy in the mouse.

    Science.gov (United States)

    Sun, Weiwei; Shi, Yu; Lee, Wen-Chih; Lee, Seung-Yon; Long, Fanxin

    2016-04-01

    Wnt signaling has emerged as a major target pathway for the development of novel bone anabolic therapies. Neutralizing antibodies against the secreted Wnt antagonist sclerostin (Scl-Ab) increase bone mass in both animal models and humans. Because we have previously shown that Rictor-dependent mTORC2 activity contributes to Wnt signaling, we test here whether Rictor is required for Scl-Ab to promote bone anabolism. Mice with Rictor deleted in the early embryonic limb mesenchyme (Prx1-Cre;Rictor(f/f), hereafter RiCKO) were subjected to Scl-Ab treatment for 5weeks starting at 4months of age. In vivo micro-computed tomography (μCT) analyses before the treatment showed that the RiCKO mice displayed normal trabecular, but less cortical bone mass than the littermate controls. After 5weeks of treatment, Scl-Ab dose-dependently increased trabecular and cortical bone mass in both control and RiCKO mice, but the increase was significantly blunted in the latter. Dynamic histomorphometry revealed that the RiCKO mice formed less bone than the control in response to Scl-Ab. In addition, the RiCKO mice possessed fewer osteoclasts than normal under the basal condition and exhibited lesser suppression in osteoclast number by Scl-Ab. Consistent with the fewer osteoclasts in vivo, bone marrow stromal cells (BMSC) from the RiCKO mice expressed less Rankl but normal levels of Opg or M-CSF, and were less effective than the control cells in supporting osteoclastogenesis in vitro. The reliance of Rankl on Rictor appeared to be independent of Wnt-β-catenin or Wnt-mTORC2 signaling as Wnt3a had no effect on Rankl expression by BMSC from either control or RICKO mice. Overall, Rictor in the limb mesenchymal lineage is required for the normal response to the anti-sclerostin therapy in both bone formation and resorption. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. Isozyme, ISSR and RAPD profiling of genotypes in marvel grass (Dichanthium annulatum).

    Science.gov (United States)

    Saxena, Raghvendra; Chandra, Amaresh

    2010-11-01

    Genetic analysis of 30 accessions of marvel grass (Dichanthium annulatum Forsk.), a tropical range grass collected from grasslands and open fields of drier regions, was carried out with the objectives of identifying unique materials that could be used in developing the core germplasm for such regions as well as to explore gene (s) for drought tolerance. Five inter-simple sequence repeat (ISSR) primers [(CA)4, (AGAC), (GACA) 4; 27 random amplified polymorphic DNA (RAPD) and four enzyme systems were employed in the present study. In total, ISSR yielded 61 (52 polymorphic), RAPD 269 (253 polymorphic) and enzyme 55 isozymes (44 polymorphic) bands. The average polymorphic information content (PIC) and marker index (MI) across all polymorphic bands of 3 markers systems ranged from 0.419 to 0.480 and 4.34 to 5.25 respectively Dendrogram analysis revealed three main clusters with all three markers. Four enzymes namely esterase (EST), polyphenoloxidase (PPO), peroxidase (PRX) and superoxide dismutase (SOD) revealed 55 alleles from a total of 16 enzyme-coding loci. Of these, 14 loci and 44 alleles were polymorphic. The mean number of alleles per locus was 3.43. Mean heterozygosity observed among the polymorphic loci ranged from 0.406 (SOD) to 0.836 (EST) and accession wise from 0.679 (1G3108) to 0.743 (IGKMD-10). Though there was intermixing of few accessions of one agro-climatic region to another largely groupings of accessions were with their regions of collections. Bootstrap analysis at 1000 iterations also showed large numbers of nodes (11 to 17) having strong clustering (> 50 bootstrap values) in all three marker systems. The accessions of the arid and drier regions forming one cluster are assigned as distinct core collection of Dichanthium and can be targeted for isolation of gene (s) for drought tolerance. Variations in isozyme allele numbers and high PIC (0.48) and MI (4.98) as observed with ISSR markers indicated their usefulness for germplasm characterization.

  5. Evaluación de la diversidad genética del género Capsicum sp. presente en los Departamentos de Vaupés, Guainía y Putumayo por medio de Isoenzimas

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    Andrade Pérez Luis Eugenio

    2000-06-01

    Full Text Available El género Capsicumcomprende 25 especies de las cuales cinco han sido domesticadas y dadoorigen a numerosos cultivares. Sin embargo, la alta selección a la que está siendo sometido elgénero podría llevarla a su erosión genética, por ello se requiere la introducción de nuevogermoplasma que suministre una fuente de diversidad genética, para el mejoramiento de loscultivares comerciales. Dicha fuente se debe encontrar en aquellas zonas donde las especiessilvestres, cercanas y/o relacionadas se distribuyen, ya que estas áreas funcionan como reser-vorio de genes y es allí donde se encuentran variedades con acervos genéticos amplios; fuentesgenéticas para resistencia a enfermedades, alta productividad y calidad nutricional. Teniendoen cuenta lo anterior la región amazónica colombiana tiene un valor potencial en la exploraciónde germoplasma importante para el género Capsicum, por ser considerada como el lugar deorigen del complejo silvestre annuum-chinense-frutescens. Así mismo se requiere de unaevaluación urgente de la diversidad genética de la región amazónica, antes de que se agotela disponibilidad de material vivo debido al proceso de deforestación. Con el propósito devalorar la diversidad genética presente del género Capsicum, en la Amazonía colombiana seutilizó la técnica de electroforésis de isoenzimas para los materiales de Ají colectados enhuertos y chagras indígenas de los departamentos de Vaupés, Guainía y Putumayo. Para laevaluación se utilizaron cinco isoenzimas polimórficas: alfabetaEST (alfabeta esterasa, GOT(glutamato oxaloacetato transaminasa, PRX (peroxidasa, 6PGDH (6-fosfoglucona-todehidrogenasa y ME (enzima málica. Con los resultados de presencia-ausencia de bandasse construyeron fenogramas con el índice de similaridad de Dice o Nei (1945 por mediodel programa estadístico NTSYS (Numerical Taxonomy and Multivariate Analisys System. Deacuerdo a los resultados se pudo establecer la alta variabilidad

  6. Sufficient Condition for Monotonicity in Constructing the Distribution Function With Bernoulli Scheme

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    Vedenyapin Aleksandr Dmitrievich

    2015-11-01

    by the function r(x, kmin: Pnk=Сnk[P(r(x, kmin]k[1-P(r(x, kmin]n-k. We defined the probability that the total index change will be in the section [x, nS] as the sum of the probabilities of incompatible events, for which the number of successes satisfies to entered inequality. Then obviously we defined the probability that the total index changing will be in the interval [nI, x. Then the function F(x was introduced, defined on the whole line, which is identical to the amount (probability that the total index changing will be in the interval in the interval (nI, nS], and is identical to zero and one in the additions. Some properties of the distribution function F(x are satisfied automatically. A sufficient condition for the monotonicity is presented in the form of Theorem 2.

  7. Magnetism in Complex Oxides Probed by Magnetocaloric Effect and Transverse Susceptibility

    Science.gov (United States)

    Bingham, Nicholas S.

    Magnetic oxides exhibit rich complexity in their fundamental physical properties determined by the intricate interplay between structural, electronic and magnetic degrees of freedom. The common themes that are often present in these systems are the phase coexistence, strong magnetostructural coupling, and possible spin frustration induced by lattice geometry. While a complete understanding of the ground state magnetic properties and cooperative phenomena in this class of compounds is key to manipulating their functionality for applications, it remains among the most challenging problems facing condensed-matter physics today. To address these outstanding issues, it is essential to employ experimental methods that allow for detailed investigations of the temperature and magnetic field response of the different phases. In this PhD dissertation, I will demonstrate the relatively unconventional experimental methods of magnetocaloric effect (MCE) and radio-frequency transverse susceptibility (TS) as powerful probes of multiple magnetic transitions, glassy phenomena, and ground state magnetic properties in a large class of complex magnetic oxides, including La0.7Ca0.3- xSrxMnO3 (x = 0, 0.05, 0.1, 0.2 and 0.25), Pr0.5Sr0.5MnO3, Pr1-xSrxCoO 3 (x = 0.3, 0.35, 0.4 and 0.5), La5/8- xPrxCa3/8MnO3 (x = 0.275 and 0.375), and Ca3Co2O 6. First, the influences of strain and grain boundaries, via chemical substitution and reduced dimensionality, were studied via MCE in La0.7Ca 0.3-xSrxMnO 3. Polycrystalline, single crystalline, and thin-film La0.7Ca 0.3-xSrxMnO 3 samples show a paramagnetic to ferromagnetic transition at a wide variety of temperatures as well as an observed change in the fundamental nature of the transition (i.e. first-order magnetic transition to second order magnetic transition) that is dependent on the chemical concentration and dimensionality. Systematic TS and MCE experiments on Pr0.5Sr0.5MnO 3 and Pr0.5Sr0.5CoO3 have uncovered the different nature of low