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  1. Loss of p53 enhances the function of the endoplasmic reticulum through activation of the IRE1α/XBP1 pathway

    Science.gov (United States)

    Kodama, Rika; Byun, Sanguine; Yoon, Kyoung Wan; Hiraki, Masatsugu; Mandinova, Anna; Lee, Sam W.

    2015-01-01

    Altered regulation of ER stress response has been implicated in a variety of human diseases, such as cancer and metabolic diseases. Excessive ER function contributes to malignant phenotypes, such as chemoresistance and metastasis. Here we report that the tumor suppressor p53 regulates ER function in response to stress. We found that loss of p53 function activates the IRE1α/XBP1 pathway to enhance protein folding and secretion through upregulation of IRE1α and subsequent activation of its target XBP1. We also show that wild-type p53 interacts with synoviolin (SYVN1)/HRD1/DER3, a transmembrane E3 ubiquitin ligase localized to ER during ER stress and removes unfolded proteins by reversing transport to the cytosol from the ER, and its interaction stimulates IRE1α degradation. Moreover, IRE1α inhibitor suppressed protein secretion, induced cell death in p53-deficient cells, and strongly suppressed the formation of tumors by p53-deficient human tumor cells in vivo compared with those that expressed wild-type p53. Therefore, our data imply that the IRE1α/XBP1 pathway serves as a target for therapy of chemoresistant tumors that express mutant p53. PMID:26254280

  2. HSP72 protects cells from ER stress-induced apoptosis via enhancement of IRE1alpha-XBP1 signaling through a physical interaction.

    LENUS (Irish Health Repository)

    Gupta, Sanjeev

    2010-01-01

    Endoplasmic reticulum (ER) stress is a feature of secretory cells and of many diseases including cancer, neurodegeneration, and diabetes. Adaptation to ER stress depends on the activation of a signal transduction pathway known as the unfolded protein response (UPR). Enhanced expression of Hsp72 has been shown to reduce tissue injury in response to stress stimuli and improve cell survival in experimental models of stroke, sepsis, renal failure, and myocardial ischemia. Hsp72 inhibits several features of the intrinsic apoptotic pathway. However, the molecular mechanisms by which Hsp72 expression inhibits ER stress-induced apoptosis are not clearly understood. Here we show that Hsp72 enhances cell survival under ER stress conditions. The UPR signals through the sensor IRE1alpha, which controls the splicing of the mRNA encoding the transcription factor XBP1. We show that Hsp72 enhances XBP1 mRNA splicing and expression of its target genes, associated with attenuated apoptosis under ER stress conditions. Inhibition of XBP1 mRNA splicing either by dominant negative IRE1alpha or by knocking down XBP1 specifically abrogated the inhibition of ER stress-induced apoptosis by Hsp72. Regulation of the UPR was associated with the formation of a stable protein complex between Hsp72 and the cytosolic domain of IRE1alpha. Finally, Hsp72 enhanced the RNase activity of recombinant IRE1alpha in vitro, suggesting a direct regulation. Our data show that binding of Hsp72 to IRE1alpha enhances IRE1alpha\\/XBP1 signaling at the ER and inhibits ER stress-induced apoptosis. These results provide a physical connection between cytosolic chaperones and the ER stress response.

  3. HSP72 protects cells from ER stress-induced apoptosis via enhancement of IRE1alpha-XBP1 signaling through a physical interaction.

    Directory of Open Access Journals (Sweden)

    Sanjeev Gupta

    2010-07-01

    Full Text Available Endoplasmic reticulum (ER stress is a feature of secretory cells and of many diseases including cancer, neurodegeneration, and diabetes. Adaptation to ER stress depends on the activation of a signal transduction pathway known as the unfolded protein response (UPR. Enhanced expression of Hsp72 has been shown to reduce tissue injury in response to stress stimuli and improve cell survival in experimental models of stroke, sepsis, renal failure, and myocardial ischemia. Hsp72 inhibits several features of the intrinsic apoptotic pathway. However, the molecular mechanisms by which Hsp72 expression inhibits ER stress-induced apoptosis are not clearly understood. Here we show that Hsp72 enhances cell survival under ER stress conditions. The UPR signals through the sensor IRE1alpha, which controls the splicing of the mRNA encoding the transcription factor XBP1. We show that Hsp72 enhances XBP1 mRNA splicing and expression of its target genes, associated with attenuated apoptosis under ER stress conditions. Inhibition of XBP1 mRNA splicing either by dominant negative IRE1alpha or by knocking down XBP1 specifically abrogated the inhibition of ER stress-induced apoptosis by Hsp72. Regulation of the UPR was associated with the formation of a stable protein complex between Hsp72 and the cytosolic domain of IRE1alpha. Finally, Hsp72 enhanced the RNase activity of recombinant IRE1alpha in vitro, suggesting a direct regulation. Our data show that binding of Hsp72 to IRE1alpha enhances IRE1alpha/XBP1 signaling at the ER and inhibits ER stress-induced apoptosis. These results provide a physical connection between cytosolic chaperones and the ER stress response.

  4. The metabolic ER stress sensor IRE1α suppresses alternative activation of macrophages and impairs energy expenditure in obesity.

    Science.gov (United States)

    Shan, Bo; Wang, Xiaoxia; Wu, Ying; Xu, Chi; Xia, Zhixiong; Dai, Jianli; Shao, Mengle; Zhao, Feng; He, Shengqi; Yang, Liu; Zhang, Mingliang; Nan, Fajun; Li, Jia; Liu, Jianmiao; Liu, Jianfeng; Jia, Weiping; Qiu, Yifu; Song, Baoliang; Han, Jing-Dong J; Rui, Liangyou; Duan, Sheng-Zhong; Liu, Yong

    2017-05-01

    Obesity is associated with metabolic inflammation and endoplasmic reticulum (ER) stress, both of which promote metabolic disease progression. Adipose tissue macrophages (ATMs) are key players orchestrating metabolic inflammation, and ER stress enhances macrophage activation. However, whether ER stress pathways underlie ATM regulation of energy homeostasis remains unclear. Here, we identified inositol-requiring enzyme 1α (IRE1α) as a critical switch governing M1-M2 macrophage polarization and energy balance. Myeloid-specific IRE1α abrogation in Ern1 f/f ; Lyz2-Cre mice largely reversed high-fat diet (HFD)-induced M1-M2 imbalance in white adipose tissue (WAT) and blocked HFD-induced obesity, insulin resistance, hyperlipidemia and hepatic steatosis. Brown adipose tissue (BAT) activity, WAT browning and energy expenditure were significantly higher in Ern1 f/f ; Lyz2-Cre mice. Furthermore, IRE1α ablation augmented M2 polarization of macrophages in a cell-autonomous manner. Thus, IRE1α senses protein unfolding and metabolic and immunological states, and consequently guides ATM polarization. The macrophage IRE1α pathway drives obesity and metabolic syndrome through impairing BAT activity and WAT browning.

  5. Arabidopsis IRE1 catalyses unconventional splicing of bZIP60 mRNA to produce the active transcription factor

    KAUST Repository

    Nagashima, Yukihiro

    2011-07-01

    IRE1 plays an essential role in the endoplasmic reticulum (ER) stress response in yeast and mammals. We found that a double mutant of Arabidopsis IRE1A and IRE1B (ire1a/ire1b) is more sensitive to the ER stress inducer tunicamycin than the wild-type. Transcriptome analysis revealed that genes whose induction was reduced in ire1a/ire1b largely overlapped those in the bzip60 mutant. We observed that the active form of bZIP60 protein detected in the wild-type was missing in ire1a/ire1b. We further demonstrated that bZIP60 mRNA is spliced by ER stress, removing 23 ribonucleotides and therefore causing a frameshift that replaces the C-terminal region of bZIP60 including the transmembrane domain (TMD) with a shorter region without a TMD. This splicing was detected in ire1a and ire1b single mutants, but not in the ire1a/ire1b double mutant. We conclude that IRE1A and IRE1B catalyse unconventional splicing of bZIP60 mRNA to produce the active transcription factor.

  6. Endoplasmic Reticulum Stress Sensor IREEnhances IL-23 Expression by Human Dendritic Cells

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    Saioa Márquez

    2017-06-01

    Full Text Available Human monocyte-derived dendritic cells (DCs exposed to pathogen-associated molecular patterns (PAMPs undergo bioenergetic changes that influence the immune response. We found that stimulation with PAMPs enhanced glycolysis in DCs, whereas oxidative phosphorylation remained unaltered. Glucose starvation and the hexokinase inhibitor 2-deoxy-d-glucose (2-DG modulated cytokine expression in stimulated DCs. Strikingly, IL23A was markedly induced upon 2-DG treatment, but not during glucose deprivation. Since 2-DG can also rapidly inhibit protein N-glycosylation, we postulated that this compound could induce IL-23 in DCs via activation of the endoplasmic reticulum (ER stress response. Indeed, stimulation of DCs with PAMPs in the presence of 2-DG robustly activated inositol-requiring protein 1α (IRE1α signaling and to a lesser extent the PERK arm of the unfolded protein response. Additional ER stressors such as tunicamycin and thapsigargin also promoted IL-23 expression by PAMP-stimulated DCs. Pharmacological, biochemical, and genetic analyses using conditional knockout mice revealed that IL-23 induction in ER stressed DCs stimulated with PAMPs was IRE1α/X-box binding protein 1-dependent upon zymosan stimulation. Interestingly, we further evidenced PERK-mediated and CAAT/enhancer-binding protein β-dependent trans-activation of IL23A upon lipopolysaccharide treatment. Our findings uncover that the ER stress response can potently modulate cytokine expression in PAMP-stimulated human DCs.

  7. Activation of IRE1α-XBP1 pathway induces cell proliferation and invasion in colorectal carcinoma

    International Nuclear Information System (INIS)

    Jin, Chun; Jin, Zhao; Chen, Nian-zhao; Lu, Min; Liu, Chang-bao; Hu, Wan-Le; Zheng, Chen-guo

    2016-01-01

    Cell proliferation and tumor metastasis are considered as the main reasons for death in colorectal carcinoma (CRC). IRE1α-XBP1 pathway is the most conserved UPR pathways, which are activated during ER stress caused by the accumulation of unfolded or misfolded protein in the lumen of ER. Here, we demonstrated the critical role of IRE1α-XBP1 pathway and underlying molecular mechanism in cell proliferation and tumor metastasis in CRC. By the use of tissue microarray analysis of samples from 119 patients with CRC, IRE1α was determined to be an independent predictor of overall survival as higher expression of IRE1α in CRC patients showed lower survival rates (p = 0.0041). RNA interference and ectopic expression of IRE1α were applied to determine the molecular effects of IRE1α in CRC cells. The silencing of IRE1α inhibited the proliferation and blocked the invasion of CRC cells in vitro, while ectopic expression of IRE1α in turn promoted cell proliferation and invasion. IRE1α-XBP1 pathway regulated the mitosis of CRC cells through the directly binding of XBP1s to Cyclin D1 promoter to activate Cyclin D1 expression. Our results reveal that IRE1α-XBP1 pathway plays an important role in tumor progression and epithelial-to-mesenchymal transition (EMT), and IRE1α could be employed as a novel prognostic marker and a promising therapeutic target for CRC. - Highlights: • IRE1 was determined to be an independent predictor of overall survival in CRC patient. • IRE1-XBP1 pathway promoted CRC cell proliferation through regulating Cyclin D1 expression. • IRE1-XBP1 pathway played important role in EMT of CRC cells.

  8. Activation of IRE1α-XBP1 pathway induces cell proliferation and invasion in colorectal carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Chun [Department of Coloproctology, The Second Affiliated Hospital of Wenzhou Medical University, Wenzhou 325000 (China); Jin, Zhao [Department of Coloproctology, Wenzhou Hospital of Integrated Traditional Chinese and Western Medicine, Wenzhou 325000 (China); Chen, Nian-zhao [Department of Medicine, The Chinese Medicine Hospital of Wenzhou, Wenzhou 325000 (China); Lu, Min; Liu, Chang-bao; Hu, Wan-Le [Department of Coloproctology, The Second Affiliated Hospital of Wenzhou Medical University, Wenzhou 325000 (China); Zheng, Chen-guo, E-mail: zhengchenguo80@163.com [Department of Coloproctology, The Second Affiliated Hospital of Wenzhou Medical University, Wenzhou 325000 (China)

    2016-01-29

    Cell proliferation and tumor metastasis are considered as the main reasons for death in colorectal carcinoma (CRC). IRE1α-XBP1 pathway is the most conserved UPR pathways, which are activated during ER stress caused by the accumulation of unfolded or misfolded protein in the lumen of ER. Here, we demonstrated the critical role of IRE1α-XBP1 pathway and underlying molecular mechanism in cell proliferation and tumor metastasis in CRC. By the use of tissue microarray analysis of samples from 119 patients with CRC, IRE1α was determined to be an independent predictor of overall survival as higher expression of IRE1α in CRC patients showed lower survival rates (p = 0.0041). RNA interference and ectopic expression of IRE1α were applied to determine the molecular effects of IRE1α in CRC cells. The silencing of IRE1α inhibited the proliferation and blocked the invasion of CRC cells in vitro, while ectopic expression of IRE1α in turn promoted cell proliferation and invasion. IRE1α-XBP1 pathway regulated the mitosis of CRC cells through the directly binding of XBP1s to Cyclin D1 promoter to activate Cyclin D1 expression. Our results reveal that IRE1α-XBP1 pathway plays an important role in tumor progression and epithelial-to-mesenchymal transition (EMT), and IRE1α could be employed as a novel prognostic marker and a promising therapeutic target for CRC. - Highlights: • IRE1 was determined to be an independent predictor of overall survival in CRC patient. • IRE1-XBP1 pathway promoted CRC cell proliferation through regulating Cyclin D1 expression. • IRE1-XBP1 pathway played important role in EMT of CRC cells.

  9. Arabidopsis IRE1 catalyses unconventional splicing of bZIP60 mRNA to produce the active transcription factor

    KAUST Repository

    Nagashima, Yukihiro; Mishiba, Kei-ichiro; Suzuki, Eiji; Shimada, Yukihisa; Iwata, Yuji; Koizumi, Nozomu

    2011-01-01

    -type. Transcriptome analysis revealed that genes whose induction was reduced in ire1a/ire1b largely overlapped those in the bzip60 mutant. We observed that the active form of bZIP60 protein detected in the wild-type was missing in ire1a/ire1b. We further demonstrated

  10. Inflammatory conditions induce IRES-dependent translation of cyp24a1.

    Directory of Open Access Journals (Sweden)

    Daniela Rübsamen

    Full Text Available Rapid alterations in protein expression are commonly regulated by adjusting translation. In addition to cap-dependent translation, which is e.g. induced by pro-proliferative signaling via the mammalian target of rapamycin (mTOR-kinase, alternative modes of translation, such as internal ribosome entry site (IRES-dependent translation, are often enhanced under stress conditions, even if cap-dependent translation is attenuated. Common stress stimuli comprise nutrient deprivation, hypoxia, but also inflammatory signals supplied by infiltrating immune cells. Yet, the impact of inflammatory microenvironments on translation in tumor cells still remains largely elusive. In the present study, we aimed at identifying translationally deregulated targets in tumor cells under inflammatory conditions. Using polysome profiling and microarray analysis, we identified cyp24a1 (1,25-dihydroxyvitamin D3 24-hydroxylase to be translationally upregulated in breast tumor cells co-cultured with conditioned medium of activated monocyte-derived macrophages (CM. Using bicistronic reporter assays, we identified and validated an IRES within the 5' untranslated region (5'UTR of cyp24a1, which enhances translation of cyp24a1 upon CM treatment. Furthermore, IRES-dependent translation of cyp24a1 by CM was sensitive to phosphatidyl-inositol-3-kinase (PI3K inhibition, while constitutive activation of Akt sufficed to induce its IRES activity. Our data provide evidence that cyp24a1 expression is translationally regulated via an IRES element, which is responsive to an inflammatory environment. Considering the negative feedback impact of cyp24a1 on the vitamin D responses, the identification of a novel, translational mechanism of cyp24a1 regulation might open new possibilities to overcome the current limitations of vitamin D as tumor therapeutic option.

  11. HCV IRES-mediated core expression in zebrafish.

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    Ye Zhao

    Full Text Available The lack of small animal models for hepatitis C virus has impeded the discovery and development of anti-HCV drugs. HCV-IRES plays an important role in HCV gene expression, and is an attractive target for antiviral therapy. In this study, we report a zebrafish model with a biscistron expression construct that can co-transcribe GFP and HCV-core genes by human hepatic lipase promoter and zebrafish liver fatty acid binding protein enhancer. HCV core translation was designed mediated by HCV-IRES sequence and gfp was by a canonical cap-dependent mechanism. Results of fluorescence image and in situ hybridization indicate that expression of HCV core and GFP is liver-specific; RT-PCR and Western blotting show that both core and gfp expression are elevated in a time-dependent manner for both transcription and translation. It means that the HCV-IRES exerted its role in this zebrafish model. Furthermore, the liver-pathological impact associated with HCV-infection was detected by examination of gene markers and some of them were elevated, such as adiponectin receptor, heparanase, TGF-β, PDGF-α, etc. The model was used to evaluate three clinical drugs, ribavirin, IFNα-2b and vitamin B12. The results show that vitamin B12 inhibited core expression in mRNA and protein levels in dose-dependent manner, but failed to impact gfp expression. Also VB12 down-regulated some gene transcriptions involved in fat liver, liver fibrosis and HCV-associated pathological process in the larvae. It reveals that HCV-IRES responds to vitamin B12 sensitively in the zebrafish model. Ribavirin did not disturb core expression, hinting that HCV-IRES is not a target site of ribavirin. IFNα-2b was not active, which maybe resulted from its degradation in vivo for the long time. These findings demonstrate the feasibility of the zebrafish model for screening of anti-HCV drugs targeting to HCV-IRES. The zebrafish system provides a novel evidence of using zebrafish as a HCV model organism.

  12. Activation of Host IRE1α-Dependent Signaling Axis Contributes the Intracellular Parasitism of Brucella melitensis

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    Aseem Pandey

    2018-04-01

    Full Text Available Brucella spp. are intracellular vacuolar pathogens that causes brucellosis, a worldwide zoonosis of profound importance. We previously demonstrated that the activity of host unfolded protein response (UPR sensor IRE1α (inositol-requiring enzyme 1 and ER-associated autophagy confer susceptibility to Brucella melitensis and Brucella abortus intracellular replication. However, the mechanism by which host IRE1α regulates the pathogen intracellular lifestyle remains elusive. In this study, by employing a diverse array of molecular approaches, including biochemical analyses, fluorescence microscopy imaging, and infection assays using primary cells derived from Ern1 (encoding IRE1 conditional knockout mice, we address this gap in our understanding by demonstrating that a novel IRE1α to ULK1, an important component for autophagy initiation, signaling axis confers susceptibility to Brucella intracellular parasitism. Importantly, deletion or inactivation of key signaling components along this axis, including IRE1α, BAK/BAX, ASK1, and JNK as well as components of the host autophagy system ULK1, Atg9a, and Beclin 1, resulted in striking disruption of Brucella intracellular trafficking and replication. Host kinases in the IRE1α-ULK1 axis, including IRE1α, ASK1, JNK1, and/or AMPKα as well as ULK1, were also coordinately phosphorylated in an IRE1α-dependent fashion upon the pathogen infection. Taken together, our findings demonstrate that the IRE1α-ULK1 signaling axis is subverted by the bacterium to promote intracellular parasitism, and provide new insight into our understanding of the molecular mechanisms of intracellular lifestyle of Brucella.

  13. MRI and contrast-enhanced ultrasound imaging for evaluation of focal irreversible electroporation treatment: results from a phase I-II study in patients undergoing IRE followed by radical prostatectomy

    International Nuclear Information System (INIS)

    Bos, Willemien van den; Bruin, D.M. de; Randen, A. van; Engelbrecht, M.R.W.; Postema, A.W.; Muller, B.G.; Zondervan, P.J.; Laguna Pes, M.P.; Reijke, T.M. de; Rosette, J.J.M.C.H. de la; Varkarakis, I.M.; Skolarikos, A.; Savci-Heijink, C.D.; Jurhill, R.R.; Wijkstra, H.

    2016-01-01

    Irreversible electroporation (IRE) is an ablative therapy with a low side-effect profile in prostate cancer. The objective was: 1) To compare the volumetric IRE ablation zone on grey-scale transrectal ultrasound (TRUS), contrast-enhanced ultrasound (CEUS) and multiparametric MRI (mpMRI) with histopathology findings; 2) To determine a reliable imaging modality to visualize the IRE ablation effects accurately. A prospective phase I-II study was performed in 16 patients scheduled for radical prostatectomy (RP). IRE of the prostate was performed 4 weeks before RP. Prior to, and 4 weeks after the IRE treatment, imaging was performed by TRUS, CEUS, and mpMRI. 3D-analysis of the ablation volumes on imaging and on H and E-stained whole-mount sections was performed. The volumes were compared and the correlation was calculated. Evaluation of the imaging demonstrated that with T2-weighted MRI, dynamic contrast enhanced (DCE) MRI, and CEUS, effects of IRE are visible. T2MRI and CEUS closely match the volumes on histopathology (Pearson correlation r = 0.88 resp. 0.80). However, IRE is not visible with TRUS. mpMRI and CEUS are appropriate for assessing IRE effects and are the most feasible imaging modalities to visualize IRE ablation zone. The imaging is concordant with results of histopathological examination. (orig.)

  14. Rapid kinetics of iron responsive element (IRE) RNA/iron regulatory protein 1 and IRE-RNA/eIF4F complexes respond differently to metal ions.

    Science.gov (United States)

    Khan, Mateen A; Ma, Jia; Walden, William E; Merrick, William C; Theil, Elizabeth C; Goss, Dixie J

    2014-06-01

    Metal ion binding was previously shown to destabilize IRE-RNA/IRP1 equilibria and enhanced IRE-RNA/eIF4F equilibria. In order to understand the relative importance of kinetics and stability, we now report rapid rates of protein/RNA complex assembly and dissociation for two IRE-RNAs with IRP1, and quantitatively different metal ion response kinetics that coincide with the different iron responses in vivo. kon, for FRT IRE-RNA binding to IRP1 was eight times faster than ACO2 IRE-RNA. Mn(2+) decreased kon and increased koff for IRP1 binding to both FRT and ACO2 IRE-RNA, with a larger effect for FRT IRE-RNA. In order to further understand IRE-mRNA regulation in terms of kinetics and stability, eIF4F kinetics with FRT IRE-RNA were determined. kon for eIF4F binding to FRT IRE-RNA in the absence of metal ions was 5-times slower than the IRP1 binding to FRT IRE-RNA. Mn(2+) increased the association rate for eIF4F binding to FRT IRE-RNA, so that at 50 µM Mn(2+) eIF4F bound more than 3-times faster than IRP1. IRP1/IRE-RNA complex has a much shorter life-time than the eIF4F/IRE-RNA complex, which suggests that both rate of assembly and stability of the complexes are important, and that allows this regulatory system to respond rapidly to change in cellular iron. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

  15. IRE1: ER stress sensor and cell fate executor.

    Science.gov (United States)

    Chen, Yani; Brandizzi, Federica

    2013-11-01

    Cells operate a signaling network termed the unfolded protein response (UPR) to monitor protein-folding capacity in the endoplasmic reticulum (ER). Inositol-requiring enzyme 1 (IRE1) is an ER transmembrane sensor that activates the UPR to maintain the ER and cellular function. Although mammalian IRE1 promotes cell survival, it can initiate apoptosis via decay of antiapoptotic miRNAs. Convergent and divergent IRE1 characteristics between plants and animals underscore its significance in cellular homeostasis. This review provides an updated scenario of the IRE1 signaling model, discusses emerging IRE1 sensing mechanisms, compares IRE1 features among species, and outlines exciting future directions in UPR research. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. IRE1α links Nck1 deficiency to attenuated PTP1B expression in HepG2 cells.

    Science.gov (United States)

    Li, Hui; Li, Bing; Larose, Louise

    2017-08-01

    PTP1B, a prototype of the non-receptor subfamily of the protein tyrosine phosphatase superfamily, plays a key role in regulating intracellular signaling from various receptor and non-receptor protein tyrosine kinases. Previously, we reported that silencing Nck1 in human hepatocellular carcinoma HepG2 cells enhances basal and growth factor-induced activation of the PI3K-Akt pathway through attenuating PTP1B expression. However, the underlying mechanism by which Nck1 depletion represses PTP1B expression remains unclear. In this study, we found that silencing Nck1 attenuates PTP1B expression in HepG2 cells through down-regulation of IRE1α. Indeed, we show that silencing Nck1 in HepG2 cells leads to decreased IRE1α expression and signaling. Accordingly, IRE1α depletion using siRNA in HepG2 cells enhances PI3K-dependent basal and growth factor-induced Akt activation, reproducing the effects of silencing Nck1 on activation of this pathway. In addition, depletion of IRE1α also leads to reduced PTP1B expression, which was rescued by ectopic expression of IRE1α in Nck1-depleted cells. Mechanistically, we found that silencing either Nck1 or IRE1α in HepG2 cells decreases PTP1B mRNA levels and stability. However, despite miR-122 levels, a miRNA targeting PTP1B 3' UTR and inducing PTP1B mRNA degradation in HepG2 cells, are increased in both Nck1- and IRE1α-depleted HepG2 cells, a miR-122 antagomir did not rescue PTP1B expression in these cells. Overall, this study highlights an important role for Nck1 in fine-tuning IRE1α expression and signaling that regulate PTP1B expression and subsequent activation of the PI3K-Akt pathway in HepG2 cells. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Structural and functional basis for RNA cleavage by Ire1

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    Stroud Robert M

    2011-07-01

    Full Text Available Abstract Background The unfolded protein response (UPR controls the protein folding capacity of the endoplasmic reticulum (ER. Central to this signaling pathway is the ER-resident bifunctional transmembrane kinase/endoribonuclease Ire1. The endoribonuclease (RNase domain of Ire1 initiates a non-conventional mRNA splicing reaction, leading to the production of a transcription factor that controls UPR target genes. The mRNA splicing reaction is an obligatory step of Ire1 signaling, yet its mechanism has remained poorly understood due to the absence of substrate-bound crystal structures of Ire1, the lack of structural similarity between Ire1 and other RNases, and a scarcity of quantitative enzymological data. Here, we experimentally define the active site of Ire1 RNase and quantitatively evaluate the contribution of the key active site residues to catalysis. Results This analysis and two new crystal structures suggest that Ire1 RNase uses histidine H1061 and tyrosine Y1043 as the general acid-general base pair contributing ≥ 7.6 kcal/mol and 1.4 kcal/mol to transition state stabilization, respectively, and asparagine N1057 and arginine R1056 for coordination of the scissile phosphate. Investigation of the stem-loop recognition revealed that additionally to the stem-loops derived from the classic Ire1 substrates HAC1 and Xbp1 mRNA, Ire1 can site-specifically and rapidly cleave anticodon stem-loop (ASL of unmodified tRNAPhe, extending known substrate specificity of Ire1 RNase. Conclusions Our data define the catalytic center of Ire1 RNase and suggest a mechanism of RNA cleavage: each RNase monomer apparently contains a separate catalytic apparatus for RNA cleavage, whereas two RNase subunits contribute to RNA stem-loop docking. Conservation of the key residues among Ire1 homologues suggests that the mechanism elucidated here for yeast Ire1 applies to Ire1 in metazoan cells, and to the only known Ire1 homologue RNase L.

  18. Ire1 Has Distinct Catalytic Mechanisms for XBP1/HAC1 Splicing and RIDD

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    Arvin B. Tam

    2014-11-01

    Full Text Available An evolutionarily conserved unfolded protein response (UPR component, IRE1, cleaves XBP1/HAC1 introns in order to generate spliced mRNAs that are translated into potent transcription factors. IRE1 also cleaves endoplasmic-reticulum-associated RNAs leading to their decay, an activity termed regulated IRE1-dependent decay (RIDD; however, the mechanism by which IRE1 differentiates intron cleavage from RIDD is not well understood. Using in vitro experiments, we found that IRE1 has two different modes of action: XBP1/HAC1 is cleaved by IRE1 subunits acting cooperatively within IRE1 oligomers, whereas a single subunit of IRE1 performs RIDD without cooperativity. Furthermore, these distinct activities can be separated by complementation of catalytically inactive IRE1 RNase and mutations at oligomerization interfaces. Using an IRE1 RNase inhibitor, STF-083010, selective inhibition of XBP1 splicing indicates that XBP1 promotes cell survival, whereas RIDD leads to cell death, revealing modulation of IRE1 activities as a drug-development strategy.

  19. Promotion of Viral IRES-Mediated Translation Initiation under Mild Hypothermia.

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    Maria Licursi

    Full Text Available Internal ribosome entry site (IRES-mediated translation is an essential replication step for certain viruses. As IRES-mediated translation is regulated differently from cap-dependent translation under various cellular conditions, we sought to investigate whether temperature influences efficiency of viral IRES-mediated translation initiation by using bicistronic reporter constructs containing an IRES element of encephalomyocarditis virus (EMCV, foot-and-mouth disease virus (FMDV, hepatitis C virus (HCV, human rhinovirus (HRV or poliovirus (PV. Under mild hypothermic conditions (30 and 35°C, we observed increases in the efficiency of translation initiation by HCV and HRV IRES elements compared to translation initiation at 37°C. The promotion of HRV IRES activity was observed as early as 2 hours after exposure to mild hypothermia. We also confirmed the promotion of translation initiation by HRV IRES under mild hypothermia in multiple cell lines. The expression levels and locations of polypyrimidine tract-binding protein (PTB and upstream of N-Ras (unr, the IRES trans-acting factors (ITAFs of HCV and HRV IRES elements, were not modulated by the temperature shift from 37°C to 30°C. Taken together, this study demonstrates that efficiency of translation initiation by some viral IRES elements is temperature dependent.

  20. Viral IRES prediction system - a web server for prediction of the IRES secondary structure in silico.

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    Jun-Jie Hong

    Full Text Available The internal ribosomal entry site (IRES functions as cap-independent translation initiation sites in eukaryotic cells. IRES elements have been applied as useful tools for bi-cistronic expression vectors. Current RNA structure prediction programs are unable to predict precisely the potential IRES element. We have designed a viral IRES prediction system (VIPS to perform the IRES secondary structure prediction. In order to obtain better results for the IRES prediction, the VIPS can evaluate and predict for all four different groups of IRESs with a higher accuracy. RNA secondary structure prediction, comparison, and pseudoknot prediction programs were implemented to form the three-stage procedure for the VIPS. The backbone of VIPS includes: the RNAL fold program, aimed to predict local RNA secondary structures by minimum free energy method; the RNA Align program, intended to compare predicted structures; and pknotsRG program, used to calculate the pseudoknot structure. VIPS was evaluated by using UTR database, IRES database and Virus database, and the accuracy rate of VIPS was assessed as 98.53%, 90.80%, 82.36% and 80.41% for IRES groups 1, 2, 3, and 4, respectively. This advance useful search approach for IRES structures will facilitate IRES related studies. The VIPS on-line website service is available at http://140.135.61.250/vips/.

  1. Structural Features of the Seneca Valley Virus Internal Ribosome Entry Site (IRES) Element: a Picornavirus with a Pestivirus-Like IRES

    DEFF Research Database (Denmark)

    Willcocks, Margaret M.; Locker, Nicolas; Gomwalk, Zarmwa

    2011-01-01

    The RNA genome of Seneca Valley virus (SVV), a recently identified picornavirus, contains an internal ribosome entry site (IRES) element which has structural and functional similarity to that from classical swine fever virus (CSFV) and hepatitis C virus, members of the FLAVIVIRIDAE: The SVV IRES...... has an absolute requirement for the presence of a short region of virus-coding sequence to allow it to function either in cells or in rabbit reticulocyte lysate. The IRES activity does not require the translation initiation factor eIF4A or intact eIF4G. The predicted secondary structure indicates...

  2. Physiological roles of Regulated Ire1 Dependent Decay

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    Dina S. Coelho

    2014-04-01

    Full Text Available Ire1 is an important transducer of the Unfolded Protein Response (UPR that is activated by the accumulation of misfolded proteins in the Endoplamic Reticulum (ER stress. Activated Ire1 mediates the splicing of an intron from the mRNA of Xbp1, causing a frame-shift during translation and introducing a new carboxyl domain in the Xbp1 protein, which only then becomes a fully functional transcription factor. Studies using cell culture systems demonstrated that Ire1 also promotes the degradation of mRNAs encoding mostly ER-targeted proteins, to reduce the load of incoming ER client proteins during ER stress. This process was called RIDD (regulated Ire1-dependent decay, but its physiological significance remained poorly characterized beyond cell culture systems. Here we review several recent studies that have highlighted the physiological roles of RIDD in specific biological paradigms, such as photoreceptor differentiation in Drosophila or mammalian liver and endocrine pancreas function. These studies demonstrate the importance of RIDD in tissues undergoing intense secretory function and highlight the physiologic role of RIDD during UPR activation in cells and organisms.

  3. Translational Control Protein 80 Stimulates IRES-Mediated Translation of p53 mRNA in Response to DNA Damage

    Directory of Open Access Journals (Sweden)

    Marie-Jo Halaby

    2015-01-01

    Full Text Available Synthesis of the p53 tumor suppressor increases following DNA damage. This increase and subsequent activation of p53 are essential for the protection of normal cells against tumorigenesis. We previously discovered an internal ribosome entry site (IRES that is located at the 5′-untranslated region (UTR of p53 mRNA and found that the IRES activity increases following DNA damage. However, the mechanism underlying IRES-mediated p53 translation in response to DNA damage is still poorly understood. In this study, we discovered that translational control protein 80 (TCP80 has increased binding to the p53 mRNA in vivo following DNA damage. Overexpression of TCP80 also leads to increased p53 IRES activity in response to DNA damage. TCP80 has increased association with RNA helicase A (RHA following DNA damage and overexpression of TCP80, along with RHA, leads to enhanced expression of p53. Moreover, we found that MCF-7 breast cancer cells with decreased expression of TCP80 and RHA exhibit defective p53 induction following DNA damage and diminished expression of its downstream target PUMA, a proapoptotic protein. Taken together, our discovery of the function of TCP80 and RHA in regulating p53 IRES and p53 induction following DNA damage provides a better understanding of the mechanisms that regulate IRES-mediated p53 translation in response to genotoxic stress.

  4. Brucella Rough Mutant Induce Macrophage Death via Activating IRE1α Pathway of Endoplasmic Reticulum Stress by Enhanced T4SS Secretion.

    Science.gov (United States)

    Li, Peng; Tian, Mingxing; Bao, Yanqing; Hu, Hai; Liu, Jiameng; Yin, Yi; Ding, Chan; Wang, Shaohui; Yu, Shengqing

    2017-01-01

    Brucella is a Gram-negative facultative intracellular pathogen that causes the worldwide zoonosis, known as brucellosis. Brucella virulence relies mostly on its ability to invade and replicate within phagocytic cells. The type IV secretion system (T4SS) and lipopolysaccharide are two major Brucella virulence factors. Brucella rough mutants reportedly induce the death of infected macrophages, which is T4SS dependent. However, the underlying molecular mechanism remains unclear. In this study, the T4SS secretion capacities of Brucella rough mutant and its smooth wild-type strain were comparatively investigated, by constructing the firefly luciferase fused T4SS effector, BPE123 and VceC. In addition, quantitative real-time PCR and western blotting were used to analyze the T4SS expression. The results showed that T4SS expression and secretion were enhanced significantly in the Brucella rough mutant. We also found that the activity of the T4SS virB operon promoter was notably increased in the Brucella rough mutant, which depends on quorum sensing-related regulators of VjbR upregulation. Cell infection and cell death assays revealed that deletion of vjbR in the Brucella rough mutant absolutely abolished cytotoxicity within macrophages by downregulating T4SS expression. This suggests that up-regulation of T4SS promoted by VjbR in rough mutant Δ rfbE contribute to macrophage death. In addition, we found that the Brucella rough mutant induce macrophage death via activating IRE1α pathway of endoplasmic reticulum stress. Taken together, our study provide evidence that in comparison to the Brucella smooth wild-type strain, VjbR upregulation in the Brucella rough mutant increases transcription of the virB operon, resulting in overexpression of the T4SS gene, accompanied by the over-secretion of effecter proteins, thereby causing the death of infected macrophages via activating IRE1α pathway of endoplasmic reticulum stress, suggesting novel insights into the molecular

  5. Brucella Rough Mutant Induce Macrophage Death via Activating IRE1α Pathway of Endoplasmic Reticulum Stress by Enhanced T4SS Secretion

    Directory of Open Access Journals (Sweden)

    Peng Li

    2017-09-01

    Full Text Available Brucella is a Gram-negative facultative intracellular pathogen that causes the worldwide zoonosis, known as brucellosis. Brucella virulence relies mostly on its ability to invade and replicate within phagocytic cells. The type IV secretion system (T4SS and lipopolysaccharide are two major Brucella virulence factors. Brucella rough mutants reportedly induce the death of infected macrophages, which is T4SS dependent. However, the underlying molecular mechanism remains unclear. In this study, the T4SS secretion capacities of Brucella rough mutant and its smooth wild-type strain were comparatively investigated, by constructing the firefly luciferase fused T4SS effector, BPE123 and VceC. In addition, quantitative real-time PCR and western blotting were used to analyze the T4SS expression. The results showed that T4SS expression and secretion were enhanced significantly in the Brucella rough mutant. We also found that the activity of the T4SS virB operon promoter was notably increased in the Brucella rough mutant, which depends on quorum sensing-related regulators of VjbR upregulation. Cell infection and cell death assays revealed that deletion of vjbR in the Brucella rough mutant absolutely abolished cytotoxicity within macrophages by downregulating T4SS expression. This suggests that up-regulation of T4SS promoted by VjbR in rough mutant ΔrfbE contribute to macrophage death. In addition, we found that the Brucella rough mutant induce macrophage death via activating IRE1α pathway of endoplasmic reticulum stress. Taken together, our study provide evidence that in comparison to the Brucella smooth wild-type strain, VjbR upregulation in the Brucella rough mutant increases transcription of the virB operon, resulting in overexpression of the T4SS gene, accompanied by the over-secretion of effecter proteins, thereby causing the death of infected macrophages via activating IRE1α pathway of endoplasmic reticulum stress, suggesting novel insights into the

  6. Divergent picornavirus IRES elements

    DEFF Research Database (Denmark)

    Belsham, Graham

    2009-01-01

    Internal ribosome entry site (IRES) elements were first identified about 20 years ago within the 5' untranslated region of picornavirus RNAs. They direct a cap-independent mechanism of translation initiation on the viral RNA. Within the picornavirus family it is now known that there are four...... classes of IRES element which vary in size (450-270nt), they also have different, complex, secondary structures and distinct requirements for cellular proteins to allow them to function. This review describes the features of each class of picornavirus IRES element but focuses on the characteristics...... of the most recently described group, initially identified within the porcine teschovirus-1 RNA, which has strong similarities to the IRES elements from within the genomes of hepatitis C virus and the pestiviruses which are members of the flavivirus family. The selection of the initiation codon...

  7. Structure of the hepatitis C virus IRES bound to the human 80S ribosome: remodeling of the HCV IRES.

    Science.gov (United States)

    Boehringer, Daniel; Thermann, Rolf; Ostareck-Lederer, Antje; Lewis, Joe D; Stark, Holger

    2005-11-01

    Initiation of translation of the hepatitis C virus (HCV) polyprotein is driven by an internal ribosome entry site (IRES) RNA that bypasses much of the eukaryotic translation initiation machinery. Here, single-particle electron cryomicroscopy has been used to study the mechanism of HCV IRES-mediated initiation. A HeLa in vitro translation system was used to assemble human IRES-80S ribosome complexes under near physiological conditions; these were stalled before elongation. Domain 2 of the HCV IRES is bound to the tRNA exit site, touching the L1 stalk of the 60S subunit, suggesting a mechanism for the removal of the HCV IRES in the progression to elongation. Domain 3 of the HCV IRES positions the initiation codon in the ribosomal mRNA binding cleft by binding helix 28 at the head of the 40S subunit. The comparison with the previously published binary 40S-HCV IRES complex reveals structural rearrangements in the two pseudoknot structures of the HCV IRES in translation initiation.

  8. New small molecule inhibitors of UPR activation demonstrate that PERK, but not IRE1α signaling is essential for promoting adaptation and survival to hypoxia

    International Nuclear Information System (INIS)

    Cojocari, Dan; Vellanki, Ravi N.; Sit, Brandon; Uehling, David; Koritzinsky, Marianne; Wouters, Bradly G.

    2013-01-01

    Background and purpose: The unfolded protein response (UPR) is activated in response to hypoxia-induced stress in the endoplasmic reticulum (ER) and consists of three distinct signaling arms. Here we explore the potential of targeting two of these arms with new potent small-molecule inhibitors designed against IRE1α and PERK. Methods: We utilized shRNAs and small-molecule inhibitors of IRE1α (4μ8c) and PERK (GSK-compound 39). XBP1 splicing and DNAJB9 mRNA was measured by qPCR and was used to monitor IREactivity. PERK activity was monitored by immunoblotting eIF2α phosphorylation and qPCR of DDIT3 mRNA. Hypoxia tolerance was measured using proliferation and clonogenic cell survival assays of cells exposed to mild or severe hypoxia in the presence of the inhibitors. Results: Using knockdown experiments we show that PERK is essential for survival of KP4 cells while knockdown of IRE1α dramatically decreases the proliferation and survival of HCT116 during hypoxia. Further, we show that in response to both hypoxia and other ER stress-inducing agents both 4μ8c and the PERK inhibitor are selective and potent inhibitors of IRE1α and PERK activation, respectively. However, despite potent inhibition of IREactivation, 4μ8c had no effect on cell proliferation or clonogenic survival of cells exposed to hypoxia. This was in contrast to the inactivation of PERK signaling with the PERK inhibitor, which reduced tolerance to hypoxia and other ER stress inducing agents. Conclusions: Our results demonstrate that IRE1α but not its splicing activity is important for hypoxic cell survival. The PERK signaling arm is uniquely important for promoting adaptation and survival during hypoxia-induced ER stress and should be the focus of future therapeutic efforts

  9. The IRES electronic seal

    International Nuclear Information System (INIS)

    Autrusson, B.; Brochard, D.; Moreau, J.F.; Martin, J.C.

    2001-01-01

    In the framework of the French Support Program for the IAEA Safeguards, the 'Institut de Protection et de Surete Nucleaire' (IPSN), developed an electronic seal called Integrated and Reusable Electronic Seal (IRES) that enables independent verification by different inspectorates (IAEA, Euratom, and National Inspectorate). The seal can be remotely interrogated by radio frequency and integrated to other Containment/surveillance systems by serial line RS 485. Data are authenticated and the IRESMAG software manages in the seal reader all functionalities of the seal and records inspection data compatible with the IAEA's Seal Database. To perform this development, IPSN relies on industrial partners: SAPHYMO for the general architecture of the seal and the electronics, THALES for the authentication of data and the security of transmission. The main features of the IRES seal are the following: Interrogation by different inspectorate, allowing independent conclusions; Recording of events, including tampering, in a non-volatile memory; Authentication of data and enhanced security of the communication between the seal and the seal reader; Remote interrogation by an inspector or/and automatic for unattended systems or remote monitoring; Reusable after erasing the seal memory and replacement of the batteries

  10. RITA enhances irradiation-induced apoptosis in p53-defective cervical cancer cells via upregulation of IRE1α/XBP1 signaling.

    Science.gov (United States)

    Zhu, Hong; Abulimiti, Muyasha; Liu, Huan; Su, Xiang-Jiang; Liu, Cai-Hong; Pei, Hai-Ping

    2015-09-01

    Radiation therapy is the most widely used treatment for patients with cervical cancer. Recent studies have shown that endoplasmic reticulum (ER) stress induces apoptosis and sensitizes tumor cells to radiotherapy, which reportedly induces ER stress in cells. Classical key tumor suppressor p53 is involved in the response to a variety of cellular stresses, including those incurred by ionizing irradiation. A recent study demonstrated that small-molecule RITA (reactivation of p53 and induction of tumor cell apoptosis) increased the radiosensitivity of tumor cells expressing mutant p53 (mtp53). In the present study, we explored the effects and the underlying mechanisms of RITA in regards to the radiosensitivity and ER stress in mtp53-expressing human cervix cancer cells. Treatment with 1 µM of RITA for 24 h before irradiation markedly decreased survival and increased apoptosis in C-33A and HT-3 cells; the effects were not significantly altered by knockdown of p53. In the irradiated C-33A and HT-3 cells, RITA significantly increased the expression of IRE1α, the spliced XBP1 mRNA level, as well as apoptosis; the effects were abolished by knockdown of IRE1α. Transcriptional pulse-chase assays revealed that RITA significantly increased the stability of IRE1α mRNA in the irradiated C-33A and HT-3 cells. In contrast, the same RITA treatment did not show any significant effect on sham-irradiated cells. In conclusion, the present study provides initial evidence that RITA upregulates the expression level of IRE1α by increasing the stability of IRE1α mRNA in irradiated mtp53-expressing cervical cancer cells; the effect leads to enhanced IRE1α/XBP1 ER stress signaling and increased apoptosis in the cells. The present study offers novel insight into the pharmacological potential of RITA in the radiotherapy for cervical cancer.

  11. Enterovirus 71 contains a type I IRES element that functions when eukaryotic initiation factor eIF4G is cleaved

    International Nuclear Information System (INIS)

    Thompson, Sunnie R.; Sarnow, Peter

    2003-01-01

    Human enterovirus 71 (EV71) is a member of the Enterovirus genus of the Picornaviridae family. Other members of this family utilize an unusual mechanism of translation initiation whereby ribosomes are recruited internally to the viral RNA by an internal ribosome site (IRES) located in their 5' noncoding regions (5' NCR). Using dicistronic reporter constructs, we demonstrate that the 5' NCRs of the 7423/MS/87 and BrCr strains of EV71 function as an IRES both in extracts and in cultured cells. Preincubation of translation extracts with purified coxsackievirus 2A protease cleaved elF4G, a component of the cap binding complex, resulting in a significant decrease in translation of capped mRNAs. In contrast, the translational efficiency of the EV71 IRES was enhanced under this condition, demonstrating that the EV71 IRES functions similar to other enterovirus IRES elements when components of the cap binding protein complex are cleaved. Finally, insertion of an upstream, out-of-frame start codon in the 5' NCR of the EV71 genome inhibited IRES activity, suggesting that EV71 can be classified as a type I IRES, in which ribosomes first bind upstream of the initiation codon and then scan the mRNA until an appropriate downstream AUG start codon is encountered and protein synthesis commences

  12. Insights into the Biology of IRES Elements through Riboproteomic Approaches

    Directory of Open Access Journals (Sweden)

    Almudena Pacheco

    2010-01-01

    Full Text Available Translation initiation is a highly regulated process that exerts a strong influence on the posttranscriptional control of gene expression. Two alternative mechanisms govern translation initiation in eukaryotic mRNAs, the cap-dependent initiation mechanism operating in most mRNAs, and the internal ribosome entry site (IRES-dependent mechanism, first discovered in picornaviruses. IRES elements are highly structured RNA sequences that, in most instances, require specific proteins for recruitment of the translation machinery. Some of these proteins are eukaryotic initiation factors. In addition, RNA-binding proteins (RBPs play a key role in internal initiation control. RBPs are pivotal regulators of gene expression in response to numerous stresses, including virus infection. This review discusses recent advances on riboproteomic approaches to identify IRES transacting factors (ITAFs and the relationship between RNA-protein interaction and IRES activity, highlighting the most relevant features on picornavirus and hepatitis C virus IRESs.

  13. Dissection of Ire1 functions reveals stress response mechanisms uniquely evolved in Candida glabrata.

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    Taiga Miyazaki

    2013-01-01

    Full Text Available Proper protein folding in the endoplasmic reticulum (ER is vital in all eukaryotes. When misfolded proteins accumulate in the ER lumen, the transmembrane kinase/endoribonuclease Ire1 initiates splicing of HAC1 mRNA to generate the bZIP transcription factor Hac1, which subsequently activates its target genes to increase the protein-folding capacity of the ER. This cellular machinery, called the unfolded protein response (UPR, is believed to be an evolutionarily conserved mechanism in eukaryotes. In this study, we comprehensively characterized mutant phenotypes of IRE1 and other related genes in the human fungal pathogen Candida glabrata. Unexpectedly, Ire1 was required for the ER stress response independently of Hac1 in this fungus. C. glabrata Ire1 did not cleave mRNAs encoding Hac1 and other bZIP transcription factors identified in the C. glabrata genome. Microarray analysis revealed that the transcriptional response to ER stress is not mediated by Ire1, but instead is dependent largely on calcineurin signaling and partially on the Slt2 MAPK pathway. The loss of Ire1 alone did not confer increased antifungal susceptibility in C. glabrata contrary to UPR-defective mutants in other fungi. Taken together, our results suggest that the canonical Ire1-Hac1 UPR is not conserved in C. glabrata. It is known in metazoans that active Ire1 nonspecifically cleaves and degrades a subset of ER-localized mRNAs to reduce the ER load. Intriguingly, this cellular response could occur in an Ire1 nuclease-dependent fashion in C. glabrata. We also uncovered the attenuated virulence of the C. glabrata Δire1 mutant in a mouse model of disseminated candidiasis. This study has unveiled the unique evolution of ER stress response mechanisms in C. glabrata.

  14. Xbp1-Independent Ire1 Signaling Is Required for Photoreceptor Differentiation and Rhabdomere Morphogenesis in Drosophila

    Directory of Open Access Journals (Sweden)

    Dina S. Coelho

    2013-11-01

    Full Text Available The unfolded protein response (UPR is composed by homeostatic signaling pathways that are activated by excessive protein misfolding in the endoplasmic reticulum. Ire1 signaling is an important mediator of the UPR, leading to the activation of the transcription factor Xbp1. Here, we show that Drosophila Ire1 mutant photoreceptors have defects in the delivery of rhodopsin-1 to the rhabdomere and in the secretion of Spacemaker/Eyes Shut into the interrhabdomeral space. However, these defects are not observed in Xbp1 mutant photoreceptors. Ire1 mutant retinas have higher mRNA levels for targets of regulated Ire1-dependent decay (RIDD, including for the fatty acid transport protein (fatp. Importantly, the downregulation of fatp by RNAi rescues the rhodopsin-1 delivery defects observed in Ire1 mutant photoreceptors. Our results show that the role of Ire1 during photoreceptor differentiation is independent of Xbp1 function and demonstrate the physiological relevance of the RIDD mechanism in this specific paradigm.

  15. Yip1A, a Novel Host Factor for the Activation of the IRE1 Pathway of the Unfolded Protein Response during Brucella Infection

    Science.gov (United States)

    Taguchi, Yuki; Imaoka, Koichi; Kataoka, Michiyo; Uda, Akihiko; Nakatsu, Daiki; Horii-Okazaki, Sakuya; Kunishige, Rina; Kano, Fumi; Murata, Masayuki

    2015-01-01

    Brucella species replicate within host cells in the form of endoplasmic reticulum (ER)-derived vacuoles. The mechanisms by which the bacteria are sequestered into such vacuoles and obtain a continuous membrane supply for their replication remain to be elucidated. In the present study, we provided several lines of evidence that demonstrate the mechanism by which B. abortus acquires the ER-derived membrane. First, during Brucella infection, the IRE1 pathway, but not the PERK and ATF6 pathways, of the unfolded protein response (UPR) was activated in a time-dependent manner, and the COPII vesicle components Sar1, Sec23, and Sec24D were upregulated. Second, a marked accretion of ER-derived vacuoles was observed around replicating bacteria using fluorescent microscopy and electron microscopy. Third, we identified a novel host factor, Yip1A, for the activation of the IRE1 pathway in response to both tunicamycin treatment and infection with B. abortus. We found that Yip1A is responsible for the phosphorylation of IRE1 through high-order assembly of Ire1 molecules at ER exit sites (ERES) under the UPR conditions. In Yip1A-knockdown cells, B. abortus failed to generate the ER-derived vacuoles, and remained in endosomal/lysosomal compartments. These results indicate that the activation of the IRE1 pathway and the subsequent formation of ER-derived vacuoles are critical for B. abortus to establish a safe replication niche, and that Yip1A is indispensable for these processes. Furthermore, we showed that the autophagy-related proteins Atg9 and WIPI1, but not DFCP1, were required for the biogenesis of the ER-derived membrane compartments.  On the basis of our findings, we propose a model for intracellular Brucella replication that exploits the host UPR and ER-derived vacuole formation machineries, both of which depend on Yip1A-mediated IRE1 activation. PMID:25742138

  16. The effects of irreversible electroporation (IRE on nerves.

    Directory of Open Access Journals (Sweden)

    Wei Li

    Full Text Available BACKGROUND: If a critical nerve is circumferentially involved with tumor, radical surgery intended to cure the cancer must sacrifice the nerve. Loss of critical nerves may lead to serious consequences. In spite of the impressive technical advancements in nerve reconstruction, complete recovery and normalization of nerve function is difficult to achieve. Though irreversible electroporation (IRE might be a promising choice to treat tumors near or involved critical nerve, the pathophysiology of the nerve after IRE treatment has not be clearly defined. METHODS: We applied IRE directly to a rat sciatic nerve to study the long term effects of IRE on the nerve. A sequence of 10 square pulses of 3800 V/cm, each 100 µs long was applied directly to rat sciatic nerves. In each animal of group I (IRE the procedure was applied to produce a treated length of about 10 mm. In each animal of group II (Control the electrodes were only applied directly on the sciatic nerve for the same time. Electrophysiological, histological, and functional studies were performed on immediately after and 3 days, 1 week, 3, 5, 7 and 10 weeks following surgery. FINDINGS: Electrophysiological, histological, and functional results show the nerve treated with IRE can attain full recovery after 7 weeks. CONCLUSION: This finding is indicative of the preservation of nerve involving malignant tumors with respect to the application of IRE pulses to ablate tumors completely. In summary, IRE may be a promising treatment tool for any tumor involving nerves.

  17. Alphavirus replicon approach to promoterless analysis of IRES elements.

    Science.gov (United States)

    Kamrud, K I; Custer, M; Dudek, J M; Owens, G; Alterson, K D; Lee, J S; Groebner, J L; Smith, J F

    2007-04-10

    Here we describe a system for promoterless analysis of putative internal ribosome entry site (IRES) elements using an alphavirus (family Togaviridae) replicon vector. The system uses the alphavirus subgenomic promoter to produce transcripts that, when modified to contain a spacer region upstream of an IRES element, allow analysis of cap-independent translation of genes of interest (GOI). If the IRES element is removed, translation of the subgenomic transcript can be reduced >95% compared to the same transcript containing a functional IRES element. Alphavirus replicons, used in this manner, offer an alternative to standard dicistronic DNA vectors or in vitro translation systems currently used to analyze putative IRES elements. In addition, protein expression levels varied depending on the spacer element located upstream of each IRES. The ability to modulate the level of expression from alphavirus vectors should extend the utility of these vectors in vaccine development.

  18. IRES-dependent translational control during virus-induced endoplasmic reticulum stress and apoptosis

    Directory of Open Access Journals (Sweden)

    Paul eHanson

    2012-03-01

    Full Text Available Many virus infections and stresses can induce endoplasmic reticulum (ER stress response, a host self defense mechanism against viral invasion and stress. During this event, viral and cellular gene expression is actively regulated and often encounters a switching of the translation initiation from cap-dependent to IRES (internal ribosome entry sites-dependent. This switching is largely dependent on the mRNA structure of the 5’untranslated region (5’UTR and on the particular stress stimuli. Picornviruses and some other viruses contain an IRES within their 5’UTR of viral genome and employ an IRES-driven mechanism for translation initiation. Recently, a growing number of cellular genes involved in growth control, cell cycle progression and apoptosis were also found to contain one or more IRES within their long highly structured 5’UTRs. These genes initiate translation usually by a cap-dependent mechanism under normal physiological conditions; however, in certain environments, such as infection, starvation and heat shock they shift translation initiation to an IRES-dependent modality. Although the molecular mechanism is not entirely understood, a number of studies have revealed that several cellular biochemical processes are responsible for the switching of translation initiation to IRES-dependent. These include the cleavage of translation initiation factors by viral and/or host proteases, phosphorylation (inactivation of host factors for translation initiation, over-production of homologous proteins of cap-binding protein eIF4E, suppression of cap-binding protein eIF4E expression by specific microRNA, activation of enzymes for mRNA decapping, as well as others. Here, we summarize the recent advances in our understanding of the molecular mechanisms for the switching of translation initiation, particularly for the proteins involved in cell survival and apoptosis in the ER stress pathways during viral infections.

  19. IRES-mediated translation of foot-and-mouth disease virus (FMDV) in cultured cells derived from FMDV-susceptible and -insusceptible animals.

    Science.gov (United States)

    Kanda, Takehiro; Ozawa, Makoto; Tsukiyama-Kohara, Kyoko

    2016-03-31

    Foot-and-mouth disease virus (FMDV) possess a positive sense, single stranded RNA genome. Internal ribosomal entry site (IRES) element exists within its 5' untranslated region (5'UTR) of the viral RNA. Translation of the viral RNA is initiated by internal entry of the 40S ribosome within the IRES element. This process is facilitated by cellular factors known as IRES trans-acting factors (ITAFs). Foot-and-mouth disease (FMD) is host-restricted disease for cloven-hoofed animals such as cattle and pigs, but the factors determining the host range have not been identified yet. Although, ITAFs are known to promote IRES-mediated translation, these findings were confirmed only in cells derived from FMDV-insusceptible animals so far. We evaluated and compared the IRES-mediated translation activities among cell lines derived from four different animal species using bicistronic luciferase reporter plasmid, which possesses an FMDV-IRES element between Renilla and Firefly luciferase genes. Furthermore, we analyzed the effect of the cellular factors on IRES-mediated translation by silencing the cellular factors using siRNA in both FMDV-susceptible and -insusceptible animal cells. Our data indicated that IRES-mediated translational activity was not linked to FMDV host range. ITAF45 promoted IRES-mediated translation in all cell lines, and the effects of poly-pyrimidine tract binding protein (PTB) and eukaryotic initiation factor 4E-binding protein 1 (4E-BP1) were observed only in FMDV-susceptible cells. Thus, PTB and 4E-BP1 may influence the host range of FMDV. IRES-mediated translation activity of FMDV was not predictive of its host range. ITAF45 promoted IRES-mediated translation in all cells, and the effects of PTB and 4E-BP1 were observed only in FMDV-susceptible cells.

  20. Characterization of Hepatitis C Virus IRES Quasispecies – From the Individual to the Pool

    Directory of Open Access Journals (Sweden)

    Václav Vopálenský

    2018-04-01

    Full Text Available Hepatitis C virus (HCV is a single-stranded positive-sense RNA virus from the genus Hepacivirus. The viral genomic +RNA is 9.6 kb long and contains highly structured 5′ and 3′ untranslated regions (UTRs and codes for a single large polyprotein, which is co- and post-translationally processed by viral and cellular proteases into at least 11 different polypeptides. Most of the 5′ UTR and an initial part of the polyprotein gene are occupied by an internal ribosome entry site (IRES, which mediates cap-independent translation of the viral proteins and allows the virus to overcome cellular antiviral defense based on the overall reduction of the cap-dependent translation initiation. We reconsidered published results concerning a search for possible correlation between patient response to interferon-based antiviral therapy and accumulation of nucleotide changes within the HCV IRES. However, we were unable to identify any such correlation. Rather than searching for individual mutations, we suggest to focus on determination of individual and collective activities of the HCV IRESs found in patient specimens. We developed a combined, fast, and undemanding approach based on high-throughput cloning of the HCV IRES species to a bicistronic plasmid followed by determination of the HCV IRES activity by flow cytometry. This approach can be adjusted for measurement of the individual HCV IRES activity and for estimation of the aggregate ability of the whole HCV population present in the specimen to synthesize viral proteins. To detect nucleotide variations in the individual IRESs, we used denaturing gradient gel electrophoresis (DGGE analysis that greatly improved identification and classification of HCV IRES variants in the sample. We suggest that determination of the collective activity of the majority of HCV IRES variants present in one patient specimen in a given time represents possible functional relations among variant sequences within the complex

  1. High epiregulin expression in human U87 glioma cells relies on IRE1α and promotes autocrine growth through EGF receptor

    International Nuclear Information System (INIS)

    Auf, Gregor; Vajkoczy, Peter; Seno, Masaharu; Bikfalvi, Andreas; Minchenko, Dmitri; Minchenko, Oleksandr; Moenner, Michel; Jabouille, Arnaud; Delugin, Maylis; Guérit, Sylvaine; Pineau, Raphael; North, Sophie; Platonova, Natalia; Maitre, Marlène; Favereaux, Alexandre

    2013-01-01

    Epidermal growth factor (EGF) receptors contribute to the development of malignant glioma. Here we considered the possible implication of the EGFR ligand epiregulin (EREG) in glioma development in relation to the activity of the unfolded protein response (UPR) sensor IRE1α. We also examined EREG status in several glioblastoma cell lines and in malignant glioma. Expression and biological properties of EREG were analyzed in human glioma cells in vitro and in human tumor xenografts with regard to the presence of ErbB proteins and to the blockade of IRE1α. Inactivation of IRE1α was achieved by using either the dominant-negative strategy or siRNA-mediated knockdown. EREG was secreted in high amounts by U87 cells, which also expressed its cognate EGF receptor (ErbB1). A stimulatory autocrine loop mediated by EREG was evidenced by the decrease in cell proliferation using specific blocking antibodies directed against either ErbB1 (cetuximab) or EREG itself. In comparison, anti-ErbB2 antibodies (trastuzumab) had no significant effect. Inhibition of IRE1α dramatically reduced EREG expression both in cell culture and in human xenograft tumor models. The high-expression rate of EREG in U87 cells was therefore linked to IRE1α, although being modestly affected by chemical inducers of the endoplasmic reticulum stress. In addition, IRE1-mediated production of EREG did not depend on IRE1 RNase domain, as neither the selective dominant-negative invalidation of the RNase activity (IRE1 kinase active) nor the siRNA-mediated knockdown of XBP1 had significant effect on EREG expression. Finally, chemical inhibition of c-Jun N-terminal kinases (JNK) using the SP600125 compound reduced the ability of cells to express EREG, demonstrating a link between the growth factor production and JNK activation under the dependence of IRE1α. EREG may contribute to glioma progression under the control of IRE1α, as exemplified here by the autocrine proliferation loop mediated in U87 cells by the

  2. Generation and analysis of an improved Foxg1-IRES-Cre driver mouse line.

    Science.gov (United States)

    Kawaguchi, Daichi; Sahara, Setsuko; Zembrzycki, Andreas; O'Leary, Dennis D M

    2016-04-01

    Foxg1 expression is highly restricted to the telencephalon and other head structures in the early embryo. This expression pattern has been exploited to generate conditional knockout mice, based on a widely used Foxg1-Cre knock-in line (Foxg1(tm1(cre)Skm)), in which the Foxg1 coding region was replaced by the Cre gene. The utility of this line, however, is severely hampered for two reasons: (1) Foxg1-Cre mice display ectopic and unpredictable Cre activity, and (2) Foxg1 haploinsufficiency can produce neurodevelopmental phenotypes. To overcome these issues, we have generated a new Foxg1-IRES-Cre knock-in mouse line, in which an IRES-Cre cassette was inserted in the 3'UTR of Foxg1 locus, thus preserving the endogenous Foxg1 coding region and un-translated gene regulatory sequences in the 3'UTR, including recently discovered microRNA target sites. We further demonstrate that the new Foxg1-IRES-Cre line displays consistent Cre activity patterns that recapitulated the endogenous Foxg1 expression at embryonic and postnatal stages without causing defects in cortical development. We conclude that the new Foxg1-IRES-Cre mouse line is a unique and advanced tool for studying genes involved in the development of the telencephalon and other Foxg1-expressing regions starting from early embryonic stages. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Specificity in endoplasmic reticulum-stress signaling in yeast entails a step-wise engagement of HAC1 mRNA to clusters of the stress sensor Ire1.

    Science.gov (United States)

    van Anken, Eelco; Pincus, David; Coyle, Scott; Aragón, Tomás; Osman, Christof; Lari, Federica; Gómez Puerta, Silvia; Korennykh, Alexei V; Walter, Peter

    2014-12-30

    Insufficient protein-folding capacity in the endoplasmic reticulum (ER) induces the unfolded protein response (UPR). In the ER lumen, accumulation of unfolded proteins activates the transmembrane ER-stress sensor Ire1 and drives its oligomerization. In the cytosol, Ire1 recruits HAC1 mRNA, mediating its non-conventional splicing. The spliced mRNA is translated into Hac1, the key transcription activator of UPR target genes that mitigate ER-stress. In this study, we report that oligomeric assembly of the ER-lumenal domain is sufficient to drive Ire1 clustering. Clustering facilitates Ire1's cytosolic oligomeric assembly and HAC1 mRNA docking onto a positively charged motif in Ire1's cytosolic linker domain that tethers the kinase/RNase to the transmembrane domain. By the use of a synthetic bypass, we demonstrate that mRNA docking per se is a pre-requisite for initiating Ire1's RNase activity and, hence, splicing. We posit that such step-wise engagement between Ire1 and its mRNA substrate contributes to selectivity and efficiency in UPR signaling.

  4. An approach to modeling and optimization of integrated renewable energy system (ires)

    Science.gov (United States)

    Maheshwari, Zeel

    The purpose of this study was to cost optimize electrical part of IRES (Integrated Renewable Energy Systems) using HOMER and maximize the utilization of resources using MATLAB programming. IRES is an effective and a viable strategy that can be employed to harness renewable energy resources to energize remote rural areas of developing countries. The resource- need matching, which is the basis for IRES makes it possible to provide energy in an efficient and cost effective manner. Modeling and optimization of IRES for a selected study area makes IRES more advantageous when compared to hybrid concepts. A remote rural area with a population of 700 in 120 households and 450 cattle is considered as an example for cost analysis and optimization. Mathematical models for key components of IRES such as biogas generator, hydropower generator, wind turbine, PV system and battery banks are developed. A discussion of the size of water reservoir required is also presented. Modeling of IRES on the basis of need to resource and resource to need matching is pursued to help in optimum use of resources for the needs. Fixed resources such as biogas and water are used in prioritized order whereas movable resources such as wind and solar can be used simultaneously for different priorities. IRES is cost optimized for electricity demand using HOMER software that is developed by the NREL (National Renewable Energy Laboratory). HOMER optimizes configuration for electrical demand only and does not consider other demands such as biogas for cooking and water for domestic and irrigation purposes. Hence an optimization program based on the need-resource modeling of IRES is performed in MATLAB. Optimization of the utilization of resources for several needs is performed. Results obtained from MATLAB clearly show that the available resources can fulfill the demand of the rural areas. Introduction of IRES in rural communities has many socio-economic implications. It brings about improvement in living

  5. The IRE1α/XBP1s Pathway Is Essential for the Glucose Response and Protection of β Cells.

    Directory of Open Access Journals (Sweden)

    Justin R Hassler

    2015-10-01

    Full Text Available Although glucose uniquely stimulates proinsulin biosynthesis in β cells, surprisingly little is known of the underlying mechanism(s. Here, we demonstrate that glucose activates the unfolded protein response transducer inositol-requiring enzyme 1 alpha (IRE1α to initiate X-box-binding protein 1 (Xbp1 mRNA splicing in adult primary β cells. Using mRNA sequencing (mRNA-Seq, we show that unconventional Xbp1 mRNA splicing is required to increase and decrease the expression of several hundred mRNAs encoding functions that expand the protein secretory capacity for increased insulin production and protect from oxidative damage, respectively. At 2 wk after tamoxifen-mediated Ire1α deletion, mice develop hyperglycemia and hypoinsulinemia, due to defective β cell function that was exacerbated upon feeding and glucose stimulation. Although previous reports suggest IRE1α degrades insulin mRNAs, Ire1α deletion did not alter insulin mRNA expression either in the presence or absence of glucose stimulation. Instead, β cell failure upon Ire1α deletion was primarily due to reduced proinsulin mRNA translation primarily because of defective glucose-stimulated induction of a dozen genes required for the signal recognition particle (SRP, SRP receptors, the translocon, the signal peptidase complex, and over 100 other genes with many other intracellular functions. In contrast, Ire1α deletion in β cells increased the expression of over 300 mRNAs encoding functions that cause inflammation and oxidative stress, yet only a few of these accumulated during high glucose. Antioxidant treatment significantly reduced glucose intolerance and markers of inflammation and oxidative stress in mice with β cell-specific Ire1α deletion. The results demonstrate that glucose activates IRE1α-mediated Xbp1 splicing to expand the secretory capacity of the β cell for increased proinsulin synthesis and to limit oxidative stress that leads to β cell failure.

  6. Hypoxic regulation of the expression of genes encoded estrogen related proteins in U87 glioma cells: eff ect of IRE1 inhibition.

    Science.gov (United States)

    Minchenko, D O; Riabovol, O O; Ratushna, O O; Minchenko, O H

    2017-01-01

    The aim of the present study was to examine the effect of inhibition of endoplasmic reticulum stress signaling, mediated by IRE1 (inositol requiring enzyme 1), which is a central mediator of the unfolded protein response on the expression of genes encoded estrogen related proteins (NRIP1/RIP140, TRIM16/EBBP, ESRRA/NR3B1, FAM162A/E2IG5, PGRMC2/PMBP, and SLC39A6/LIV-1) and their hypoxic regulation in U87 glioma cells for evaluation of their possible significance in the control of glioma cells proliferation. The expression of NRIP1, EBBP, ESRRA, E2IG5, PGRMC2, and SLC39A6 genes in U87 glioma cells, transfected by empty vector pcDNA3.1 (control) and cells without IRE1 signaling enzyme function (transfected by dnIRE1) upon hypoxia, was studied by a quantitative polymerase chain reaction. Inhibition of both enzymatic activities (kinase and endoribonuclease) of IRE1 signaling enzyme function up-regulates the expression of EBBP, E2IG5, PGRMC2, and SLC39A6 genes is in U87 glioma cells in comparison with the control glioma cells, with more significant changes for E2IG5 and PGRMC2 genes. At the same time, the expression of NRIP1 and ESRRA genes is strongly down-regulated in glioma cells upon inhibition of IRE1. We also showed that hypoxia increases the expression of E2IG5, PGRMC2, and EBBP genes and decreases NRIP1 and ESRRA genes expression in control glioma cells. Furthermore, the inhibition of IRE1 in U87 glioma cells decreases the eff ect of hypoxia on the expression of E2IG5 and PGRMC2 genes, eliminates hypoxic regulation of NRIP1 gene, and enhances the sensitivity of ESRRA gene to hypoxic condition. Furthermore, the expression of SLC39A6 gene is resistant to hypoxia in both the glioma cells with and without IRE1 signaling enzyme function. Results of this investigation demonstrate that inhibition of IRE1 signaling enzyme function affects the expression of NRIP1, EBBP, ESRRA, E2IG5, PGRMC2, and SLC39A6 genes in U87 glioma cells in gene specific manner and these changes

  7. The mechanism of translation initiation on Aichivirus RNA mediated by a novel type of picornavirus IRES.

    Science.gov (United States)

    Yu, Yingpu; Sweeney, Trevor R; Kafasla, Panagiota; Jackson, Richard J; Pestova, Tatyana V; Hellen, Christopher Ut

    2011-08-26

    Picornavirus mRNAs contain IRESs that sustain their translation during infection, when host protein synthesis is shut off. The major classes of picornavirus IRESs (Types 1 and 2) have distinct structures and sequences, but initiation on both is determined by their specific interaction with eIF4G. We report here that Aichivirus (AV), a member of the Kobuvirus genus of Picornaviridae, contains an IRES that differs structurally from Type 1 and Type 2 IRESs. Its function similarly involves interaction with eIF4G, but its eIF4G-interacting domain is structurally distinct, although it contains an apical eIF4G-interacting motif similar to that in Type 2 IRESs. Like Type 1 and Type 2 IRESs, AV IRES function is enhanced by pyrimidine tract-binding protein (PTB), but the pattern of PTB's interaction with each of these IRESs is distinct. Unlike all known IRESs, the AV IRES is absolutely dependent on DHX29, a requirement imposed by sequestration of its initiation codon in a stable hairpin.

  8. AtLa1 protein initiates IRES-dependent translation of WUSCHEL mRNA and regulates the stem cell homeostasis of Arabidopsis in response to environmental hazards.

    Science.gov (United States)

    Cui, Yuchao; Rao, Shaofei; Chang, Beibei; Wang, Xiaoshuang; Zhang, Kaidian; Hou, Xueliang; Zhu, Xueyi; Wu, Haijun; Tian, Zhaoxia; Zhao, Zhong; Yang, Chengwei; Huang, Tao

    2015-10-01

    Plant stem cells are hypersensitive to environmental hazards throughout their life cycle, but the mechanism by which plants safeguard stem cell homeostasis in response to environmental hazards is largely unknown. The homeodomain transcription factor WUSCHEL (WUS) protein maintains the stem cell pool in the shoot apical meristem of Arabidopsis. Here, we demonstrate that the translation of WUS mRNA is directed by an internal ribosomal entry site (IRES) located in the 5'-untranslated region. The AtLa1 protein, an RNA-binding factor, binds to the 5'-untranslated region and initiates the IRES-dependent translation of WUS mRNA. Knockdown of AtLa1 expression represses the WUS IRES-dependent translation and leads to the arrest of growth and development. The AtLa1 protein is mainly located in the nucleoplasm. However, environmental hazards promote the nuclear-to-cytoplasmic translocation of the AtLa1 protein, which further enhances the IRES-dependent translation of WUS mRNA. Genetic evidence indicates that the WUS protein increases the tolerance of the shoot apical meristem to environmental hazards. Based on these results, we conclude that the stem cell niche in Arabidopsis copes with environmental hazards by enhancing the IRES-dependent translation of WUS mRNA under the control of the AtLa1 protein. © 2015 John Wiley & Sons Ltd.

  9. Initiation of translation in bacteria by a structured eukaryotic IRES RNA.

    Science.gov (United States)

    Colussi, Timothy M; Costantino, David A; Zhu, Jianyu; Donohue, John Paul; Korostelev, Andrei A; Jaafar, Zane A; Plank, Terra-Dawn M; Noller, Harry F; Kieft, Jeffrey S

    2015-03-05

    The central dogma of gene expression (DNA to RNA to protein) is universal, but in different domains of life there are fundamental mechanistic differences within this pathway. For example, the canonical molecular signals used to initiate protein synthesis in bacteria and eukaryotes are mutually exclusive. However, the core structures and conformational dynamics of ribosomes that are responsible for the translation steps that take place after initiation are ancient and conserved across the domains of life. We wanted to explore whether an undiscovered RNA-based signal might be able to use these conserved features, bypassing mechanisms specific to each domain of life, and initiate protein synthesis in both bacteria and eukaryotes. Although structured internal ribosome entry site (IRES) RNAs can manipulate ribosomes to initiate translation in eukaryotic cells, an analogous RNA structure-based mechanism has not been observed in bacteria. Here we report our discovery that a eukaryotic viral IRES can initiate translation in live bacteria. We solved the crystal structure of this IRES bound to a bacterial ribosome to 3.8 Å resolution, revealing that despite differences between bacterial and eukaryotic ribosomes this IRES binds directly to both and occupies the space normally used by transfer RNAs. Initiation in both bacteria and eukaryotes depends on the structure of the IRES RNA, but in bacteria this RNA uses a different mechanism that includes a form of ribosome repositioning after initial recruitment. This IRES RNA bridges billions of years of evolutionary divergence and provides an example of an RNA structure-based translation initiation signal capable of operating in two domains of life.

  10. Characterization of the functional role of nucleotides within the URE2 IRES element and the requirements for eIF2A-mediated repression.

    Science.gov (United States)

    Reineke, Lucas C; Merrick, William C

    2009-12-01

    Cap-independent initiation of translation is thought to promote protein synthesis on some mRNAs during times when cap-dependent initiation is down-regulated. However, the mechanism of cap-independent initiation is poorly understood. We have previously reported the secondary structure within the yeast minimal URE2 IRES element. In this study, we sought to investigate the mechanism of internal initiation in yeast by assessing the functional role of nucleotides within the minimal URE2 IRES element, and delineating the cis-sequences that modulate levels of internal initiation using a monocistronic reporter vector. Furthermore, we compared the eIF2A sensitivity of the URE2 IRES element with some of the invasive growth IRES elements using DeltaeIF2A yeast. We found that the stability of the stem-loop structure within the minimal URE2 IRES element is not a critical determinant of optimal IRES activity, and the downstream sequences that modulate URE2 IRES-mediated translation can be defined to discrete regions within the URE2 coding region. Repression of internal initiation on the URE2 minimal IRES element by eIF2A is not dependent on the stability of the secondary structure within the URE2 IRES element. Our data also indicate that eIF2A-mediated repression is not specific to the URE2 IRES element, as both the GIC1 and PAB1 IRES elements are repressed by eIF2A. These data provide valuable insights into the mRNA requirements for internal initiation in yeast, and insights into the mechanism of eIF2A-mediated suppression.

  11. The UPR reduces glucose metabolism via IRE1 signaling.

    Science.gov (United States)

    van der Harg, Judith M; van Heest, Jessica C; Bangel, Fabian N; Patiwael, Sanne; van Weering, Jan R T; Scheper, Wiep

    2017-04-01

    Neurons are highly dependent on glucose. A disturbance in glucose homeostasis therefore poses a severe risk that is counteracted by activation of stress responses to limit damage and restore the energy balance. A major stress response that is activated under conditions of glucose deprivation is the unfolded protein response (UPR) that is aimed to restore proteostasis in the endoplasmic reticulum. The key signaling of the UPR involves the transient activation of a transcriptional program and an overall reduction of protein synthesis. Since the UPR is strategically positioned to sense and integrate metabolic stress signals, it is likely that - apart from its adaptive response to restore proteostasis - it also directly affects metabolic pathways. Here we investigate the direct role of the UPR in glucose homeostasis. O-GlcNAc is a post-translational modification that is highly responsive to glucose fluctuations. We find that UPR activation results in decreased O-GlcNAc modification, in line with reduced glucose metabolism. Our data indicate that UPR activation has no direct impact on the upstream processes in glucose metabolism; glucose transporter expression, glucose uptake and hexokinase activity. In contrast, prolonged UPR activation decreases glycolysis and mitochondrial metabolism. Decreased mitochondrial respiration is not accompanied by apoptosis or a structural change in mitochondria indicating that the reduction in metabolic rate upon UPR activation is a physiological non-apoptotic response. Metabolic decrease is prevented if the IRE1 pathway of the UPR is inhibited. This indicates that activation of IRE1 signaling induces a reduction in glucose metabolism, as part of an adaptive response. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. PRMT5 regulates IRES-dependent translation via methylation of hnRNP A1

    Science.gov (United States)

    Gao, Guozhen; Dhar, Surbhi

    2017-01-01

    Abstract The type II arginine methyltransferase PRMT5 is responsible for the symmetric dimethylation of histone to generate the H3R8me2s and H4R3me2s marks, which correlate with the repression of transcription. However, the protein level of a number of genes (MEP50, CCND1, MYC, HIF1a, MTIF and CDKN1B) are reported to be downregulated by the loss of PRMT5, while their mRNA levels remain unchanged, which is counterintuitive for PRMT5's proposed role as a transcription repressor. We noticed that the majority of the genes regulated by PRMT5, at the posttranscriptional level, express mRNA containing an internal ribosome entry site (IRES). Using an IRES-dependent reporter system, we established that PRMT5 facilitates the translation of a subset of IRES-containing genes. The heterogeneous nuclear ribonucleoprotein, hnRNP A1, is an IRES transacting factor (ITAF) that regulates the IRES-dependent translation of Cyclin D1 and c-Myc. We showed that hnRNP A1 is methylated by PRMT5 on two residues, R218 and R225, and that this methylation facilitates the interaction of hnRNP A1 with IRES RNA to promote IRES-dependent translation. This study defines a new role for PRMT5 regulation of cellular protein levels, which goes beyond the known functions of PRMT5 as a transcription and splicing regulator. PMID:28115626

  13. Role of IRE1α/XBP-1 in Cystic Fibrosis Airway Inflammation

    Directory of Open Access Journals (Sweden)

    Carla M. P. Ribeiro

    2017-01-01

    Full Text Available Cystic fibrosis (CF pulmonary disease is characterized by chronic airway infection and inflammation. The infectious and inflamed CF airway environment impacts on the innate defense of airway epithelia and airway macrophages. The CF airway milieu induces an adaptation in these cells characterized by increased basal inflammation and a robust inflammatory response to inflammatory mediators. Recent studies have indicated that these responses depend on activation of the unfolded protein response (UPR. This review discusses the contribution of airway epithelia and airway macrophages to CF airway inflammatory responses and specifically highlights the functional importance of the UPR pathway mediated by IRE1/XBP-1 in these processes. These findings suggest that targeting the IRE1/XBP-1 UPR pathway may be a therapeutic strategy for CF airway disease.

  14. IRE/F as a Cross-Curricular Collaborative Genre of Implicit Argumentation

    Science.gov (United States)

    Lawrence, Ann M.; Crespo, Sandra

    2016-01-01

    We contend that the classroom-discourse routine of IRE/F (teacher initiation, student response, teacher evaluation/follow-up) is a genre of argumentation that is both collaborative and implicit because teachers and students cooperate during IRE/F exchanges not only to make and mirror knowledge claims but also to suppress justification for those…

  15. Crystallization and preliminary X-ray diffraction analysis of iron regulatory protein 1 in complex with ferritin IRE RNA

    International Nuclear Information System (INIS)

    Selezneva, Anna I.; Cavigiolio, Giorgio; Theil, Elizabeth C.; Walden, William E.; Volz, Karl

    2006-01-01

    The iron regulatory protein IRP1 has been crystallized in a complex with ferritin IRE RNA and a complete data set has been collected to 2.8 Å resolution. Iron regulatory protein 1 (IRP1) is a bifunctional protein with activity as an RNA-binding protein or as a cytoplasmic aconitase. Interconversion of IRP1 between these mutually exclusive states is central to cellular iron regulation and is accomplished through iron-responsive assembly and disassembly of a [4Fe–4S] cluster. When in its apo form, IRP1 binds to iron responsive elements (IREs) found in mRNAs encoding proteins of iron storage and transport and either prevents translation or degradation of the bound mRNA. Excess cellular iron stimulates the assembly of a [4Fe–4S] cluster in IRP1, inhibiting its IRE-binding ability and converting it to an aconitase. The three-dimensional structure of IRP1 in its different active forms will provide details of the interconversion process and clarify the selective recognition of mRNA, Fe–S sites and catalytic activity. To this end, the apo form of IRP1 bound to a ferritin IRE was crystallized. Crystals belong to the monoclinic space group P2 1 , with unit-cell parameters a = 109.6, b = 80.9, c = 142.9 Å, β = 92.0°. Native data sets have been collected from several crystals with resolution extending to 2.8 Å and the structure has been solved by molecular replacement

  16. IRESPred: Web Server for Prediction of Cellular and Viral Internal Ribosome Entry Site (IRES)

    Science.gov (United States)

    Kolekar, Pandurang; Pataskar, Abhijeet; Kulkarni-Kale, Urmila; Pal, Jayanta; Kulkarni, Abhijeet

    2016-01-01

    Cellular mRNAs are predominantly translated in a cap-dependent manner. However, some viral and a subset of cellular mRNAs initiate their translation in a cap-independent manner. This requires presence of a structured RNA element, known as, Internal Ribosome Entry Site (IRES) in their 5′ untranslated regions (UTRs). Experimental demonstration of IRES in UTR remains a challenging task. Computational prediction of IRES merely based on sequence and structure conservation is also difficult, particularly for cellular IRES. A web server, IRESPred is developed for prediction of both viral and cellular IRES using Support Vector Machine (SVM). The predictive model was built using 35 features that are based on sequence and structural properties of UTRs and the probabilities of interactions between UTR and small subunit ribosomal proteins (SSRPs). The model was found to have 75.51% accuracy, 75.75% sensitivity, 75.25% specificity, 75.75% precision and Matthews Correlation Coefficient (MCC) of 0.51 in blind testing. IRESPred was found to perform better than the only available viral IRES prediction server, VIPS. The IRESPred server is freely available at http://bioinfo.net.in/IRESPred/. PMID:27264539

  17. hNIS-IRES-eGFP Dual Reporter Gene Imaging

    Directory of Open Access Journals (Sweden)

    Jiantu Che

    2005-04-01

    Full Text Available The human and rodent sodium iodide symporters (NIS have recently been cloned and are being investigated as potential therapeutic and reporter genes. We have extended this effort by constructing an internal ribosomal entry site (IRES-linked human NIS (hNIS-enhanced green fluorescent protein (eGFP hybrid reporter gene for both nuclear and optical imaging. A self-inactivating retroviral vector, termed pQCNIG, containing hNIS-IRES-eGFP dual reporter gene, driven by a constitutive CMV promoter, was constructed and used to generate RG2-pQCNIG cells and RG2-pQCNIG tumors. 131I-iodide and 99mTcO4-pertechnetate accumulation studies plus fluorescence microscopy and intensity assays were performed in vitro, and gamma camera imaging studies in RG2-pQCNIG and RG2 tumor-bearing athymic rats were performed. RG2-pQCNIG cells expressed high levels of hNIS protein and showed high intensity of eGFP fluorescence compared with RG2 wild-type cells. RG2-pQCNIG cells accumulated Na131I and 99mTcO4– to a 50:1 and a 170:1 tissue/medium ratio at 10 min, compared with 0.8:1.2 tissue/medium ratio in wild-type RG2 cells. A significant correlation between radiotracer accumulation and eGFP fluorescence intensity was demonstrated. RG2-pQCNIG and RG2 tumors were readily differentiated by in vivo gamma camera imaging; radiotracer uptake increased in RG2-pQCNIG but declined in RG2 tumors over the 50-min imaging period. Stomach and thyroid were the major organs of radionuclide accumulation. The IRES-linked hNIS-eGFP dual reporter gene is functional and stable in transduced RG2-pQCNIG cells. Optical and nuclear imaging of tumors produced from these cell lines provides the opportunity to monitor tumor growth and response to therapy. These studies indicate the potential for a wider application of hNIS reporter imaging and translation into patient studies using radioisotopes that are currently available for human use for both SPECT and PET imaging.

  18. Careful treatment planning enables safe ablation of liver tumors adjacent to major blood vessels by percutaneous irreversible electroporation (IRE).

    Science.gov (United States)

    Kos, Bor; Voigt, Peter; Miklavcic, Damijan; Moche, Michael

    2015-09-01

    Irreversible electroporation (IRE) is a tissue ablation method, which relies on the phenomenon of electroporation. When cells are exposed to a sufficiently electric field, the plasma membrane is disrupted and cells undergo an apoptotic or necrotic cell death. Although heating effects are known IRE is considered as non-thermal ablation technique and is currently applied to treat tumors in locations where thermal ablation techniques are contraindicated. The manufacturer of the only commercially available pulse generator for IRE recommends a voltage-to-distance ratio of 1500 to 1700 V/cm for treating tumors in the liver. However, major blood vessels can influence the electric field distribution. We present a method for treatment planning of IRE which takes the influence of blood vessels on the electric field into account; this is illustrated on a treatment of 48-year-old patient with a metastasis near the remaining hepatic vein after a right side hemi-hepatectomy. Output of the numerical treatment planning method shows that a 19.9 cm3 irreversible electroporation lesion was generated and the whole tumor was covered with at least 900 V/cm. This compares well with the volume of the hypodense lesion seen in contrast enhanced CT images taken after the IRE treatment. A significant temperature raise occurs near the electrodes. However, the hepatic vein remains open after the treatment without evidence of tumor recurrence after 6 months. Treatment planning using accurate computer models was recognized as important for electrochemotherapy and irreversible electroporation. An important finding of this study was, that the surface of the electrodes heat up significantly. Therefore the clinical user should generally avoid placing the electrodes less than 4 mm away from risk structures when following recommendations of the manufacturer.

  19. Intestinal IRE1 Is Required for Increased Triglyceride Metabolism and Longer Lifespan under Dietary Restriction.

    Science.gov (United States)

    Luis, Nuno Miguel; Wang, Lifen; Ortega, Mauricio; Deng, Hansong; Katewa, Subhash D; Li, Patrick Wai-Lun; Karpac, Jason; Jasper, Heinrich; Kapahi, Pankaj

    2016-10-25

    Dietary restriction (DR) is one of the most robust lifespan-extending interventions in animals. The beneficial effects of DR involve a metabolic adaptation toward increased triglyceride usage. The regulatory mechanism and the tissue specificity of this metabolic switch remain unclear. Here, we show that the IRE1/XBP1 endoplasmic reticulum (ER) stress signaling module mediates metabolic adaptation upon DR in flies by promoting triglyceride synthesis and accumulation in enterocytes (ECs) of the Drosophila midgut. Consistently, IRE1/XBP1 function in ECs is required for increased longevity upon DR. We further identify sugarbabe, a Gli-like zinc-finger transcription factor, as a key mediator of the IRE1/XBP1-regulated induction of de novo lipogenesis in ECs. Overexpression of sugarbabe rescues metabolic and lifespan phenotypes of IRE1 loss-of-function conditions. Our study highlights the critical role of metabolic adaptation of the intestinal epithelium for DR-induced lifespan extension and explores the IRE1/XBP1 signaling pathway regulating this adaptation and influencing lifespan. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.

  20. Endoplasmic reticulum stress and IRE-1 signaling cause apoptosis in colon cancer cells in response to andrographolide treatment.

    Science.gov (United States)

    Banerjee, Aditi; Ahmed, Hafiz; Yang, Peixin; Czinn, Steven J; Blanchard, Thomas G

    2016-07-05

    The plant metabolite andrographolide induces cell cycle arrest and apoptosis in cancer cells. The mechanism(s) by which andrographolide induces apoptosis however, have not been elucidated. The present study was performed to determine the molecular events that promote apoptosis in andrographolide treated cells using T84, HCT116 and COLO 205 colon cancer cell lines. Andrographolide was determined to limit colony formation and Ki67 expression, alter nuclear morphology, increase cytoplasmic histone-associated-DNA-fragments, and increase cleaved caspase-3 levels. Andrographolide also induced significantly higher expression of endoplasmic reticulum (ER) stress proteins GRP-78 and IRE-1 by 48 h but not PERK or ATF6. Apoptosis signaling molecules BAX, spliced XBP-1 and CHOP were also significantly increased. Moreover, chemical inhibition of ER stress or IRE-1 depletion with siRNA in andrographolide treated cells significantly limited expression of IRE-1 and CHOP as determined by immunofluorescence staining, real time PCR, or immunobloting. This was accompanied by a decreased BAX/Bcl-2 ratio. Andrographolide significantly promotes cancer cell death compared to normal cells. These data demonstrate that andrographolide associated ER stress contributes to apoptosis through the activation of a pro-apoptotic GRP-78/IRE-1/XBP-1/CHOP signaling pathway.

  1. Cryo-EM structure of Hepatitis C virus IRES bound to the human ribosome at 3.9-Å resolution.

    Science.gov (United States)

    Quade, Nick; Boehringer, Daniel; Leibundgut, Marc; van den Heuvel, Joop; Ban, Nenad

    2015-07-08

    Hepatitis C virus (HCV), a widespread human pathogen, is dependent on a highly structured 5'-untranslated region of its mRNA, referred to as internal ribosome entry site (IRES), for the translation of all of its proteins. The HCV IRES initiates translation by directly binding to the small ribosomal subunit (40S), circumventing the need for many eukaryotic translation initiation factors required for mRNA scanning. Here we present the cryo-EM structure of the human 40S ribosomal subunit in complex with the HCV IRES at 3.9 Å resolution, determined by focused refinement of an 80S ribosome-HCV IRES complex. The structure reveals the molecular details of the interactions between the IRES and the 40S, showing that expansion segment 7 (ES7) of the 18S rRNA acts as a central anchor point for the HCV IRES. The structural data rationalizes previous biochemical and genetic evidence regarding the initiation mechanism of the HCV and other related IRESs.

  2. Switch from cap- to factorless IRES-dependent 0 and +1 frame translation during cellular stress and dicistrovirus infection.

    Directory of Open Access Journals (Sweden)

    Qing S Wang

    Full Text Available Internal ribosome entry sites (IRES are utilized by a subset of cellular and viral mRNAs to initiate translation during cellular stress and virus infection when canonical cap-dependent translation is compromised. The intergenic region (IGR IRES of the Dicistroviridae uses a streamlined mechanism in which it can directly recruit the ribosome in the absence of initiation factors and initiates translation using a non-AUG codon. A subset of IGR IRESs including that from the honey bee viruses can also direct translation of an overlapping +1 frame gene. In this study, we systematically examined cellular conditions that lead to IGR IRES-mediated 0 and +1 frame translation in Drosophila S2 cells. Towards this, a novel bicistronic reporter that exploits the 2A "stop-go" peptide was developed to allow the detection of IRES-mediated translation in vivo. Both 0 and +1 frame translation by the IGR IRES are stimulated under a number of cellular stresses and in S2 cells infected by cricket paralysis virus, demonstrating a switch from cap-dependent to IRES-dependent translation. The regulation of the IGR IRES mechanism ensures that both 0 frame viral structural proteins and +1 frame ORFx protein are optimally expressed during virus infection.

  3. HCV IRES domain IIb affects the configuration of coding RNA in the 40S subunit's decoding groove.

    Science.gov (United States)

    Filbin, Megan E; Kieft, Jeffrey S

    2011-07-01

    Hepatitis C virus (HCV) uses a structured internal ribosome entry site (IRES) RNA to recruit the translation machinery to the viral RNA and begin protein synthesis without the ribosomal scanning process required for canonical translation initiation. Different IRES structural domains are used in this process, which begins with direct binding of the 40S ribosomal subunit to the IRES RNA and involves specific manipulation of the translational machinery. We have found that upon initial 40S subunit binding, the stem-loop domain of the IRES that contains the start codon unwinds and adopts a stable configuration within the subunit's decoding groove. This configuration depends on the sequence and structure of a different stem-loop domain (domain IIb) located far from the start codon in sequence, but spatially proximal in the IRES•40S complex. Mutation of domain IIb results in misconfiguration of the HCV RNA in the decoding groove that includes changes in the placement of the AUG start codon, and a substantial decrease in the ability of the IRES to initiate translation. Our results show that two distal regions of the IRES are structurally communicating at the initial step of 40S subunit binding and suggest that this is an important step in driving protein synthesis.

  4. Inhibition of Hepatitis C Virus in Mice by a Small Interfering RNA Targeting a Highly Conserved Sequence in Viral IRES Pseudoknot.

    Directory of Open Access Journals (Sweden)

    Jae-Su Moon

    Full Text Available The hepatitis C virus (HCV internal ribosome entry site (IRES that directs cap-independent viral translation is a primary target for small interfering RNA (siRNA-based HCV antiviral therapy. However, identification of potent siRNAs against HCV IRES by bioinformatics-based siRNA design is a challenging task given the complexity of HCV IRES secondary and tertiary structures and association with multiple proteins, which can also dynamically change the structure of this cis-acting RNA element. In this work, we utilized siRNA tiling approach whereby siRNAs were tiled with overlapping sequences that were shifted by one or two nucleotides over the HCV IRES stem-loop structures III and IV spanning nucleotides (nts 277-343. Based on their antiviral activity, we mapped a druggable region (nts 313-343 where the targets of potent siRNAs were enriched. siIE22, which showed the greatest anti-HCV potency, targeted a highly conserved sequence across diverse HCV genotypes, locating within the IRES subdomain IIIf involved in pseudoknot formation. Stepwise target shifting toward the 5' or 3' direction by 1 or 2 nucleotides reduced the antiviral potency of siIE22, demonstrating the importance of siRNA accessibility to this highly structured and sequence-conserved region of HCV IRES for RNA interference. Nanoparticle-mediated systemic delivery of the stability-improved siIE22 derivative gs_PS1 siIE22, which contains a single phosphorothioate linkage on the guide strand, reduced the serum HCV genome titer by more than 4 log10 in a xenograft mouse model for HCV replication without generation of resistant variants. Our results provide a strategy for identifying potent siRNA species against a highly structured RNA target and offer a potential pan-HCV genotypic siRNA therapy that might be beneficial for patients resistant to current treatment regimens.

  5. IRSS: a web-based tool for automatic layout and analysis of IRES secondary structure prediction and searching system in silico

    Directory of Open Access Journals (Sweden)

    Hong Jun-Jie

    2009-05-01

    Full Text Available Abstract Background Internal ribosomal entry sites (IRESs provide alternative, cap-independent translation initiation sites in eukaryotic cells. IRES elements are important factors in viral genomes and are also useful tools for bi-cistronic expression vectors. Most existing RNA structure prediction programs are unable to deal with IRES elements. Results We designed an IRES search system, named IRSS, to obtain better results for IRES prediction. RNA secondary structure prediction and comparison software programs were implemented to construct our two-stage strategy for the IRSS. Two software programs formed the backbone of IRSS: the RNAL fold program, used to predict local RNA secondary structures by minimum free energy method; and the RNA Align program, used to compare predicted structures. After complete viral genome database search, the IRSS have low error rate and up to 72.3% sensitivity in appropriated parameters. Conclusion IRSS is freely available at this website http://140.135.61.9/ires/. In addition, all source codes, precompiled binaries, examples and documentations are downloadable for local execution. This new search approach for IRES elements will provide a useful research tool on IRES related studies.

  6. 42 CFR 423.2010 - When CMS, the IRE, or Part D plan sponsors may participate in an ALJ hearing.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 3 2010-10-01 2010-10-01 false When CMS, the IRE, or Part D plan sponsors may... PRESCRIPTION DRUG BENEFIT Reopening, ALJ Hearings, MAC review, and Judicial Review § 423.2010 When CMS, the IRE... require, CMS, the IRE, and/or the Part D plan sponsor to participate in any proceedings before the ALJ...

  7. Muudatused tulekahjuhäiresüsteemide ehitamisel / Veiko Jürisson

    Index Scriptorium Estoniae

    Jürisson, Veiko, 1956-2008

    2005-01-01

    Tulekahju-signalisatsioonisüsteemi ehitusele eelneva kirjaliku nõusoleku taotlemisest kohalikult omavalitsuselt, valminud süsteemi üleandmisest omanikule ning automaatse tulekahjuhäiresüsteemi kasutusloa andmisest

  8. Reduced IRE1α mediates apoptotic cell death by disrupting calcium homeostasis via the InsP3 receptor.

    Science.gov (United States)

    Son, S M; Byun, J; Roh, S-E; Kim, S J; Mook-Jung, I

    2014-04-17

    The endoplasmic reticulum (ER) is not only a home for folding and posttranslational modifications of secretory proteins but also a reservoir for intracellular Ca(2+). Perturbation of ER homeostasis contributes to the pathogenesis of various neurodegenerative diseases, such as Alzheimer's and Parkinson diseases. One key regulator that underlies cell survival and Ca(2+) homeostasis during ER stress responses is inositol-requiring enzyme 1α (IRE1α). Despite extensive studies on this ER membrane-associated protein, little is known about the molecular mechanisms by which excessive ER stress triggers cell death and Ca(2+) dysregulation via the IRE1α-dependent signaling pathway. In this study, we show that inactivation of IRE1α by RNA interference increases cytosolic Ca(2+) concentration in SH-SY5Y cells, leading to cell death. This dysregulation is caused by an accelerated ER-to-cytosolic efflux of Ca(2+) through the InsP3 receptor (InsP3R). The Ca(2+) efflux in IRE1α-deficient cells correlates with dissociation of the Ca(2+)-binding InsP3R inhibitor CIB1 and increased complex formation of CIB1 with the pro-apoptotic kinase ASK1, which otherwise remains inactivated in the IRE1α-TRAF2-ASK1 complex. The increased cytosolic concentration of Ca(2+) induces mitochondrial production of reactive oxygen species (ROS), in particular superoxide, resulting in severe mitochondrial abnormalities, such as fragmentation and depolarization of membrane potential. These Ca(2+) dysregulation-induced mitochondrial abnormalities and cell death in IRE1α-deficient cells can be blocked by depleting ROS or inhibiting Ca(2+) influx into the mitochondria. These results demonstrate the importance of IRE1α in Ca(2+) homeostasis and cell survival during ER stress and reveal a previously unknown Ca(2+)-mediated cell death signaling between the IRE1α-InsP3R pathway in the ER and the redox-dependent apoptotic pathway in the mitochondrion.

  9. The IRES electronic seal

    International Nuclear Information System (INIS)

    Gourlez, P.; Funk, P.; Brochard, D.; Moreau, J.F.; Martin, J.C.

    2001-01-01

    In the framework of the French Support Program for the IAEA Safeguards, the 'Institut de Protection et de Surete Nucleaire' (IPSN), developed an electronic seal called Integrated and Reusable Electronic Seal (IRES) that enables independent verification by different inspectorates (IAEA, Euratom, and National Inspectorate) Furthermore, a bilateral co-ordination between Euratom and French domestic safeguards takes place in some French facilities regarding a common approach concerning the seals especially in case of crisis situation. The seal can be remotely interrogated by radio frequency and integrated to other Containment/surveillance systems by serial line RS 485. Data are authenticated and the IRESMAG software manages in the seal reader all functionalities of the seal and records inspection data compatible with the IAEA's Seal Database

  10. Interactome Screening Identifies the ER Luminal Chaperone Hsp47 as a Regulator of the Unfolded Protein Response Transducer IRE1α.

    Science.gov (United States)

    Sepulveda, Denisse; Rojas-Rivera, Diego; Rodríguez, Diego A; Groenendyk, Jody; Köhler, Andres; Lebeaupin, Cynthia; Ito, Shinya; Urra, Hery; Carreras-Sureda, Amado; Hazari, Younis; Vasseur-Cognet, Mireille; Ali, Maruf M U; Chevet, Eric; Campos, Gisela; Godoy, Patricio; Vaisar, Tomas; Bailly-Maitre, Béatrice; Nagata, Kazuhiro; Michalak, Marek; Sierralta, Jimena; Hetz, Claudio

    2018-01-18

    Maintenance of endoplasmic reticulum (ER) proteostasis is controlled by a dynamic signaling network known as the unfolded protein response (UPR). IRE1α is a major UPR transducer, determining cell fate under ER stress. We used an interactome screening to unveil several regulators of the UPR, highlighting the ER chaperone Hsp47 as the major hit. Cellular and biochemical analysis indicated that Hsp47 instigates IRE1α signaling through a physical interaction. Hsp47 directly binds to the ER luminal domain of IRE1α with high affinity, displacing the negative regulator BiP from the complex to facilitate IRE1α oligomerization. The regulation of IRE1α signaling by Hsp47 is evolutionarily conserved as validated using fly and mouse models of ER stress. Hsp47 deficiency sensitized cells and animals to experimental ER stress, revealing the significance of Hsp47 to global proteostasis maintenance. We conclude that Hsp47 adjusts IRE1α signaling by fine-tuning the threshold to engage an adaptive UPR. Copyright © 2018 Elsevier Inc. All rights reserved.

  11. The use of IRE in multi-modality treatment for oligometastatic pancreatic cancer.

    Science.gov (United States)

    Hong, Young; Rice, Jonathan; Sharma, Divyansh; Martin, Robert C G

    2018-03-02

    Pancreatic ductal adenocarcinoma (PDAC) often presents late with only 20% of patients being candidates for resection while majority already have advanced metastases with median overall survival of 3-6 months. Currently, the role of oligometastasectomy and local therapy options in PDAC is unknown in patients who have favorable response to systemic chemotherapy. The aim of this study is to analyze the survival outcome of oligometastasectomy and local IRE therapy in select patients who are treated with systemic chemotherapy for PDAC metastases. We utilized a prospective database from 2010 to 2016 to identify patients with local surgical therapy after induction systemic chemotherapy for oligometastatic PDAC (Stage 4). The initial local therapy treatment of distant metastatic lesions was followed by adjuvant chemotherapy. Subsequently, resection of the primary PDAC in conjunction with irreversible electroporation (IRE) was performed after favorable response by RECIST criteria. Seven patients were identified with metastatic PDAC treated with oligometastasectomy and/or local therapy. There was single metastatic lesion in 43% (3/7) of which 57% (4/7) were localized in the liver. The treatment of the primary pancreatic cancer was performed utilizing IRE in situ in 6/7 (86%) of patients in our study with resection or radiation of oligometastasis. The median survival in our study group was 16 months with 28% (2/7) patients who remain NED (range 16-41 months). Combination of systemic chemotherapy and oligometastasectomy with adjunctive local IRE therapy is a feasible treatment strategy in highly select patients with oligometastatic PDAC that demonstrate favorable tumor biology with objective response to systemic therapy. Copyright © 2018 Elsevier Inc. All rights reserved.

  12. Enhancement of internal ribosome entry site-mediated translation and replication of hepatitis C virus by PD98059

    International Nuclear Information System (INIS)

    Murata, Takayuki; Hijikata, Makoto; Shimotohno, Kunitada

    2005-01-01

    Translation initiation of hepatitis C virus (HCV) occurs in an internal ribosome entry site (IRES)-dependent manner. We found that HCV IRES-dependent protein synthesis is enhanced by PD98059, an inhibitor of the extracellular signal-regulated kinase (ERK) signaling pathway, while cellular cap-dependent translation was relatively unaffected by the compound. Treatment of cells with PD98059 allowed for robust HCV replication following cellular incubation with HCV-positive serum. Though the molecular mechanism underlying IRES enhancement remains elusive, PD98059 is a potent accelerator of HCV RNA replication

  13. Ire1 mediated mRNA splicing in a C-terminus deletion mutant of Drosophila Xbp1.

    Directory of Open Access Journals (Sweden)

    Dina S Coelho

    Full Text Available The Unfolded Protein Response is a homeostatic mechanism that permits eukaryotic cells to cope with Endoplasmic Reticulum (ER stress caused by excessive accumulation of misfolded proteins in the ER lumen. The more conserved branch of the UPR relies on an ER transmembrane enzyme, Ire1, which, upon ER stress, promotes the unconventional splicing of a small intron from the mRNA encoding the transcription factor Xbp1. In mammals, two specific regions (the hydrophobic region 2--HR2--and the C-terminal translational pausing site present in the Xbp1unspliced protein mediate the recruitment of the Xbp1 mRNA-ribosome-nascent chain complex to the ER membrane, so that Xbp1 mRNA can be spliced by Ire1. Here, we generated a Drosophila Xbp1 deletion mutant (Excision101 lacking both HR2 and C-terminal region, but not the Ire1 splicing site. We show that Ire1-dependent splicing of Xbp1 mRNA is reduced, but not abolished in Excision101. Our results suggest the existence of additional mechanisms for ER membrane targeting of Xbp1 mRNA that are independent of the C-terminal domain of Drosophila Xbp1unspliced.

  14. The unfolded protein response in melanocytes: activation in response to chemical stressors of the endoplasmic reticulum and tyrosinase misfolding.

    Science.gov (United States)

    Manga, Prashiela; Bis, Sabina; Knoll, Kristen; Perez, Beremis; Orlow, Seth J

    2010-10-01

    Accumulation of proteins in the endoplasmic reticulum (ER) triggers the unfolded protein response (UPR), comprising three signaling pathways initiated by Ire1, Perk and Atf6 respectively. Unfolded protein response activation was compared in chemically stressed murine wildtype melanocytes and mutant melanocytes that retain tyrosinase in the ER. Thapsigargin, an ER stressor, activated all pathways in wildtype melanocytes, triggering Caspase 12-mediated apoptosis at toxic doses. Albino melanocytes expressing mutant tyrosinase showed evidence of ER stress with increased Ire1 expression, but the downstream effector, Xbp1, was not activated even following thapsigargin treatment. Attenuation of Ire1 signaling was recapitulated in wildtype melanocytes treated with thapsigargin for 8 days, with diminished Xbp1 activation observed after 4 days. Atf6 was also activated in albino melanocytes, with no response to thapsigargin, while the Perk pathway was not activated and thapsigargin treatment elicited robust expression of the downstream effector CCAAT-enhancer-binding protein homologous protein. Thus, melanocytes adapt to ER stress by attenuating two UPR pathways.

  15. First Delayed Resection Findings After Irreversible Electroporation (IRE) of Human Localised Renal Cell Carcinoma (RCC) in the IRENE Pilot Phase 2a Trial

    Energy Technology Data Exchange (ETDEWEB)

    Wendler, Johann Jakob, E-mail: johann.wendler@med.ovgu.de [Otto von Guericke University of Magdeburg, Department of Urology, University Hospital (Germany); Ricke, Jens, E-mail: jens.Ricke@med.ovgu.de; Pech, Maciej, E-mail: macej.pech@med.ovgu.de; Fischbach, Frank, E-mail: frank.fischbach@med.ovgu.de; Jürgens, Julian, E-mail: julian.juergens@med.ovgu.de [University of Magdeburg, Department of Radiology (Germany); Siedentopf, Sandra, E-mail: sandra.siedentopf@med.ovgu.de; Roessner, Albert, E-mail: albert.roessner@med.ovgu.de [University of Magdeburg, Institute of Pathology (Germany); Porsch, Markus, E-mail: markus.porsch@med.ovgu.de; Baumunk, Daniel, E-mail: daniel.baumunk@med.ovgu.de; Schostak, Martin, E-mail: martin.schostak@med.ovgu.de [Otto von Guericke University of Magdeburg, Department of Urology, University Hospital (Germany); Köllermann, Jens, E-mail: jens.koellermann@sana.de [Sana Klinikum Offenbach Am Main, Institute of Pathology (Germany); Liehr, Uwe-Bernd, E-mail: uwe-bernd.liehr@med.ovgu.de [Otto von Guericke University of Magdeburg, Department of Urology, University Hospital (Germany)

    2016-02-15

    IntroductionIt is postulated that focal IRE affords complete ablation of soft-tissue tumours while protecting the healthy peritumoral tissue. Therefore, IRE may be an interesting option for minimally invasive, kidney-tissue-sparing, non-thermal ablation of renal tumours.AimWith this current pilot study (“IRENE trial”), we present the first detailed histopathological data of IRE of human RCC followed by delayed tumour resection. The aim of this interim analysis of the first three patients was to investigate the ablation efficiency of percutaneous image-guided focal IRE in RCC, to assess whether a complete ablation of T1a RCC and tissue preservation with the NanoKnife system is possible and to decide whether the ablation parameters need to be altered.MethodsFollowing resection 4 weeks after percutaneous IRE, the success of ablation and detailed histopathological description were used to check the ablation parameters.ResultsThe IRE led to a high degree of damage to the renal tumours (1 central, 2 peripheral; size range 15–17 mm). The postulated homogeneous, isomorphic damage was only partly confirmed. We found a zonal structuring of the ablation zone, negative margins and, enclosed within the ablation zone, very small tumour residues of unclear malignancy.ConclusionAccording to these initial, preliminary study results of the first three renal cases, a new zonal distribution of IRE damage was described and the curative intended, renal saving focal ablation of localised RCC below <3 cm by percutaneous IRE by the NanoKnife system appears to be possible, but needs further, systematic evaluation for this treatment method and treatment protocol.

  16. Effect of CD34+ cord blood stem cell transfected by plasmid vector pIRES2-FL-IL-3 on the mice after irradiation

    International Nuclear Information System (INIS)

    Zhang Yong; Zhang Linsheng; Zhang Hongbing; Guo Chaohua; Tong Shiwu

    2008-01-01

    Objective: To observe the effect of CD34 cord blood stem cell transfected by plasmid vector plRES2-FL-IL-3 on the mouse after irradiation and to investigate its mechanisms. Methods: In the co-expressed group (12 mice), CD 34 + cord blood stem cells were transfected by plasmid vector pIRES2-FL-IL-3.5 x lO 5 cells were injected intravenously in the mouse. The hemogram changes in mice were detected 2, 4 and 6 weeks after radiation. At 6 weeks after irradiation, the expression of the CD 34 in spleen was detected by immumofluorescence method. The mRNA level and the activity of IL-3 and FL were detected by RT-PCR and Western blot. Other 3 groups were CD 34 + cell group (CD 34 group), pIRES2-IL-3 group(IL 3 group) and pIRES2-FL group(FL group), and there were 12 mice in each group. Results: The survival rate of CD 34 group, IL3 group and FL group at the 6th week were 25.0% (3/12), 50.0% (6/12) and 50.0% (6/12), respectively. It was 91.7% (11/12) in the co-expressed group, which was higher than those in the other groups. The expression of the CD 34 of spleen in the co-expressed group was higher than those of the other groups. The mRNA level and the activity of IL-3 and FL of spleen in the co-expressed group were higher than those in the other groups too. Conclusions: The CD 34 '+ cord blood stem cells transfected by plasmid vector pIRES2-FL-IL-3 have hemogenesis promotion effect on the mice after irradiation, which was related with the aggregation, proliferation of stem cells and the high expression of the interest proteins.. (authors)

  17. Targeting the CACNA1A IRES as a Treatment for Spinocerebellar Ataxia Type 6.

    Science.gov (United States)

    Pastor, Parviz Daniel Hejazi; Du, Xiaofei; Fazal, Sarah; Davies, Andre N; Gomez, Christopher M

    2018-02-01

    We have discovered that the P/Q-type voltage-gated Ca 2+ channel (VGCC) gene, CACNA1A, encodes both the α1A (Cav2.1) subunit and a newly recognized transcription factor, α1ACT, by means of a novel internal ribosomal entry site (IRES) within the α1A C-terminal coding region. α1ACT, when mutated with an expansion of the polyglutamine tract in the C-terminus, gives rise to spinocerebellar ataxia type 6 (SCA6). Because silencing of the entire CACNA1A gene would result in the loss of the essential Cav2.1 channel, the IRES controlling α1ACT expression is an excellent target for selective silencing of α1ACT as a therapeutic intervention for SCA6. We performed a high-throughput screen of FDA-approved small molecules using a dual luciferase reporter system and identified ten hits able to selectively inhibit the IRES. We identified four main candidates that showed selective suppression of α1ACT relative to α1A in HEK cells expressing a native CACNA1A vector. We previously pursued another avenue of molecular intervention through miRNA silencing. We studied three human miRNAs (miRNA-711, -3191-5p, -4786) that would potentially bind to sequences within the CACNA1A IRES region, based on an miRNA prediction program. Only miRNA-3191-5p was found to selectively inhibit the translation of α1ACT in cells. We developed a hyperacute model of SCA6 in mice by injecting a pathogenic form of the IRES-mediated α1ACT (AAV9-α1ACTQ33). Finally, we tested the effectiveness of the miRNA therapy by co-expressing either control miRNA or miRNA-3191-5p and found that miRNA-3191-5p decreased the levels of α1ACTQ33 and prevented the hyperacute disease in mice. These studies provide the proof of principle that a therapy directed at selectively preventing α1ACT expression could be used to treat SCA6.

  18. Irreversible electroporation ablation (IRE of unresectable soft tissue tumors: learning curve evaluation in the first 150 patients treated.

    Directory of Open Access Journals (Sweden)

    Prejesh Philips

    Full Text Available BACKGROUND: Irreversible electroporation (IRE is a novel technology that uses peri-target discrete probes to deliver high-voltage localized electric current to induce cell death without thermal-induced coagulative necrosis. "Learnability" and consistently effective results by novice practitioners is essential for determining acceptance of novel techniques. This multi-center prospectively-collected database study evaluates the learning curve of IRE. METHODS: Analysis of 150 consecutive patients over 7 institutions from 9/2010-7/2012 was performed with patients treated divided into 3 groups A (1(st 50 patients treated, B (2(nd 50 and C (3(rd 50 patients treated chronologically and analyzed for outcomes. RESULTS: A total of 167 IRE procedures were performed, with a majority being liver(39.5% and pancreatic(35.5% lesions. The three groups were similar with respect to co-morbidities and demographics. Group C had larger lesions (3.9 vs 3 cm,p=0.001, more numerous lesions (3.2 vs 2.2,p=0.07, more vascular invasion(p=0.001, underwent more associated procedures(p=0.001 and had longer operative times(p<0.001. Despite this, they had similar complication and high-grade complication rates(p=0.24. Attributable morbidity rate was 13.3%(total 29.3% and high-grade complications were seen in 4.19%(total 12.6%. Pancreatic lesions(p=0.001 and laparotomy(p=0.001 were associated with complications. CONCLUSION: The review represents that single largest review of IRE soft tissue ablation demonstrating initial patient selection and safety. Over time, complex treatments of larger lesions and lesions with greater vascular involvement were performed without a significant increase in adverse effects or impact on local relapse free survival. This evolution demonstrates the safety profile of IRE and speed of graduation to more complex lesions, which was greater than 5 cases by institution. IRE is a safe and effective alternative to conventional ablation with a demonstrable

  19. Gamma background radiation monitoring results (1990-95) in the environs around IRE OSCOM, Orissa using TLDs

    Energy Technology Data Exchange (ETDEWEB)

    Mehta, N K; Bapat, V N; Nambi, K S.V. [Bhabha Atomic Research Centre, Mumbai (India). Environmental Assessment Div.; Saha, S C [Bhabha Atomic Research Centre, Bombay (India). Health Physics Div.

    1997-09-01

    Quarterly environmental radiation monitoring data using TLDs in about 28 locations in and around IRE-OSCOM covering a six year period 1990-95 is presented in the report. While the indoor radiation levels in beach areas having monazite deposits recorded annual average of 653{+-}230 mR/y, that in IRE residential colony gave a value of 240 {+-}30 mR/y. The radiation levels recorded inside the OSCOM plant are well within the limits prescribed for occupational radiation exposures. (author). 3 refs., 7 figs., 1 tab.

  20. Gamma background radiation monitoring results (1990-95) in the environs around IRE OSCOM, Orissa using TLDs

    International Nuclear Information System (INIS)

    Mehta, N.K.; Bapat, V.N.; Nambi, K.S.V.; Saha, S.C.

    1997-01-01

    Quarterly environmental radiation monitoring data using TLDs in about 28 locations in and around IRE-OSCOM covering a six year period 1990-95 is presented in the report. While the indoor radiation levels in beach areas having monazite deposits recorded annual average of 653±230 mR/y, that in IRE residential colony gave a value of 240 ±30 mR/y. The radiation levels recorded inside the OSCOM plant are well within the limits prescribed for occupational radiation exposures. (author). 3 refs., 7 figs., 1 tab

  1. Minimal-length Synthetic shRNAs Formulated with Lipid Nanoparticles are Potent Inhibitors of Hepatitis C Virus IRES-linked Gene Expression in Mice

    Directory of Open Access Journals (Sweden)

    Anne Dallas

    2013-01-01

    Full Text Available We previously identified short synthetic shRNAs (sshRNAs that target a conserved hepatitis C virus (HCV sequence within the internal ribosome entry site (IRES of HCV and potently inhibit HCV IRES-linked gene expression. To assess in vivo liver delivery and activity, the HCV-directed sshRNA, SG220 was formulated into lipid nanoparticles (LNP and injected i.v. into mice whose livers supported stable HCV IRES-luciferase expression from a liver-specific promoter. After a single injection, RNase protection assays for the sshRNA and 3H labeling of a lipid component of the nanoparticles showed efficient liver uptake of both components and long-lasting survival of a significant fraction of the sshRNA in the liver. In vivo imaging showed a dose-dependent inhibition of luciferase expression (>90% 1 day after injection of 2.5 mg/kg sshRNA with t1/2 for recovery of about 3 weeks. These results demonstrate the ability of moderate levels of i.v.-injected, LNP-formulated sshRNAs to be taken up by liver hepatocytes at a level sufficient to substantially suppress gene expression. Suppression is rapid and durable, suggesting that sshRNAs may have promise as therapeutic agents for liver indications.

  2. Structural Analysis of PTM Hotspots (SAPH-ire)--A Quantitative Informatics Method Enabling the Discovery of Novel Regulatory Elements in Protein Families.

    Science.gov (United States)

    Dewhurst, Henry M; Choudhury, Shilpa; Torres, Matthew P

    2015-08-01

    Predicting the biological function potential of post-translational modifications (PTMs) is becoming increasingly important in light of the exponential increase in available PTM data from high-throughput proteomics. We developed structural analysis of PTM hotspots (SAPH-ire)--a quantitative PTM ranking method that integrates experimental PTM observations, sequence conservation, protein structure, and interaction data to allow rank order comparisons within or between protein families. Here, we applied SAPH-ire to the study of PTMs in diverse G protein families, a conserved and ubiquitous class of proteins essential for maintenance of intracellular structure (tubulins) and signal transduction (large and small Ras-like G proteins). A total of 1728 experimentally verified PTMs from eight unique G protein families were clustered into 451 unique hotspots, 51 of which have a known and cited biological function or response. Using customized software, the hotspots were analyzed in the context of 598 unique protein structures. By comparing distributions of hotspots with known versus unknown function, we show that SAPH-ire analysis is predictive for PTM biological function. Notably, SAPH-ire revealed high-ranking hotspots for which a functional impact has not yet been determined, including phosphorylation hotspots in the N-terminal tails of G protein gamma subunits--conserved protein structures never before reported as regulators of G protein coupled receptor signaling. To validate this prediction we used the yeast model system for G protein coupled receptor signaling, revealing that gamma subunit-N-terminal tail phosphorylation is activated in response to G protein coupled receptor stimulation and regulates protein stability in vivo. These results demonstrate the utility of integrating protein structural and sequence features into PTM prioritization schemes that can improve the analysis and functional power of modification-specific proteomics data. © 2015 by The American

  3. An adenine-to-guanine nucleotide change in the IRES SL-IV domain of picornavirus/hepatitis C chimeric viruses leads to a nonviable phenotype

    International Nuclear Information System (INIS)

    McKnight, Kevin L.; Sandefur, Stephanie; Phipps, Krista M.; Heinz, Beverly A.

    2003-01-01

    The inability for the internal ribosomal entry site (IRES) of hepatitis C virus (HCV) to be readily studied in the context of viral replication has been circumvented by constructing chimeras such as with poliovirus (PV), in which translation of the genome polyprotein is under control of the HCV IRES. During our attempts to configure the PV/HCV chimera for our drug discovery efforts, we discovered that an adenine- (A) to-guanine (G) change at nt 350 in domain IV of the HCV IRES resulted in a nonviable phenotype. Similarly, a mengovirus (MV)/HCV chimera using the same configuration with a G at nt 350 (G-350) was found to be nonviable. In contrast, a bovine viral diarrhea virus (BVDV)/HCV chimera remained viable with G-350 in the HCV IRES insert. Second-site, resuscitating mutations were identified from the G-350 PV/HCV and MV/HCV viruses after blind passaging. For both viruses, the resuscitating mutations involved destabilization of domain IV in the HCV IRES. The nonviability of G-350 in the picornavirus/HCV chimeric background might be linked to translation efficiency as indicated by analyses with dual reporter and PV/HCV replicon constructs

  4. Generation of Oxtr cDNA(HA)-Ires-Cre Mice for Gene Expression in an Oxytocin Receptor Specific Manner.

    Science.gov (United States)

    Hidema, Shizu; Fukuda, Tomokazu; Hiraoka, Yuichi; Mizukami, Hiroaki; Hayashi, Ryotaro; Otsuka, Ayano; Suzuki, Shingo; Miyazaki, Shinji; Nishimori, Katsuhiko

    2016-05-01

    The neurohypophysial hormone oxytocin (OXT) and its receptor (OXTR) have critical roles in the regulation of pro-social behaviors, including social recognition, pair bonding, parental behavior, and stress-related responses. Supporting this hypothesis, a portion of patients suffering from autism spectrum disorder have mutations, such as single nucleotide polymorphisms, or epigenetic modifications in their OXTR gene. We previously reported that OXTR-deficient mice exhibit pervasive social deficits, indicating the critical role of OXTR in social behaviors. In the present study, we generated Oxtr cDNA(HA)-Ires-Cre knock-in mice, expressing both OXTR and Cre recombinase under the control of the endogenous Oxtr promoter. Knock-in cassette of Oxtr cDNA(HA)-Ires-Cre consisted of Oxtr cDNA tagged with the hemagglutinin epitope at the 3' end (Oxtr cDNA(HA)), internal ribosomal entry site (Ires), and Cre. Cre was expressed in the uterus, mammary gland, kidney, and brain of Oxtr cDNA(HA)-Ires-Cre knock-in mice. Furthermore, the distribution of Cre in the brain was similar to that observed in Oxtr-Venus fluorescent protein expressing mice (Oxtr-Venus), another animal model previously generated by our group. Social behavior of Oxtr cDNA(HA)-Ires-Cre knock-in mice was similar to that of wild-type animals. We demonstrated that this construct is expressed in OXTR-expressing neurons specifically after an infection with the recombinant adeno-associated virus carrying the flip-excision switch vector. Using this system, we showed the transport of the wheat-germ agglutinin tracing molecule from the OXTR-expressing neurons to the innervated neurons in knock-in mice. This study might contribute to the monosynaptic analysis of neuronal circuits and to the optogenetic analysis of neurons expressing OXTR. © 2015 Wiley Periodicals, Inc.

  5. Careful treatment planning enables safe ablation of liver tumors adjacent to major blood vessels by percutaneous irreversible electroporation (IRE

    Directory of Open Access Journals (Sweden)

    Kos Bor

    2015-09-01

    Full Text Available Background. Irreversible electroporation (IRE is a tissue ablation method, which relies on the phenomenon of electroporation. When cells are exposed to a sufficiently electric field, the plasma membrane is disrupted and cells undergo an apoptotic or necrotic cell death. Although heating effects are known IRE is considered as non-thermal ablation technique and is currently applied to treat tumors in locations where thermal ablation techniques are contraindicated.

  6. Analysis of Factors Affecting System Performance in the ASpIRE Challenge

    Science.gov (United States)

    2015-12-13

    performance in the ASpIRE ( Automatic Speech recognition In Reverberant Environments) challenge. In particular, overall word error rate (WER) of the solver...in mismatched conditions. Index Terms: speech recognition, reverberant rooms, microphone audio 1. Introduction The development of automatic ...IEEE Workshop on Automatic Speech Recognition and Understanding, 2005. [7] Harper, M., The Automatic Speech Recognition in Reverberant

  7. Ground Reaction Force and Mechanical Differences Between the Interim Resistive Exercise Device (iRED) and Smith Machine While Performing a Squat

    Science.gov (United States)

    Amonette, William E.; Bentley, Jason R.; Lee, Stuart M. C.; Loehr, James A.; Schneider, Suzanne

    2004-01-01

    Musculoskeletal unloading in microgravity has been shown to induce losses in bone mineral density, muscle cross-sectional area, and muscle strength. Currently, an Interim Resistive Exercise Device (iRED) is being flown on board the ISS to help counteract these losses. Free weight training has shown successful positive musculoskeletal adaptations. In biomechanical research, ground reaction forces (GRF) trajectories are used to define differences between exercise devices. The purpose of this evaluation is to quantify the differences in GRF between the iRED and free weight exercise performed on a Smith machine during a squat. Due to the differences in resistance properties, inertial loading and load application to the body between the two devices, we hypothesize that subjects using iRED will produce GRF that are significantly different from the Smith machine. There will be differences in bar/harness range of motion and the time when peak GRF occurred in the ROMbar. Three male subjects performed three sets of ten squats on the iRED and on the Smith Machine on two separate days at a 2-second cadence. Statistically significant differences were found between the two devices in all measured GRF variables. Average Fz and Fx during the Smith machine squat were significantly higher than iRED. Average Fy (16.82 plus or minus.23; p less than .043) was significantly lower during the Smith machine squat. The mean descent/ascent ratio of the magnitude of the resultant force vector of all three axes for the Smith machine and iRED was 0.95 and 0.72, respectively. Also, the point at which maximum Fz occurred in the range of motion (Dzpeak) was at different locations with the two devices.

  8. BECCS Market Launch Strategy Aiming to Help Ensure Reliable Grid Power at High Penetrations of IRE (Intermittent Renewable Electricity)

    Science.gov (United States)

    WIlliams, R. H.

    2017-12-01

    Despite its recognized importance for carbon (C)-mitigation, progress in advancing biomass energy with CO2 capture and sequestration (BECCS) has been slow. A BECCS market launch strategy based on technologies ready for commercial-scale demonstration is discussed—based on co-gasification of coal and biomass to make H2 with CCS. H2 so produced would be a key element of a H2 balancing capacity (H2-BC) strategy for ensuring reliable grid power at high IRE penetrations. High grid penetrations of IRE must be complemented by fast-ramping balancing (backup and/or storage) capacity (BC) to ensure reliable grid power. BC provided now by natural gas-fired gas turbine combined cycle and combustion turbine units would eventually have to be decarbonized to realize C-mitigation goals, via CCS or other means. Capital-intensive CCS energy systems require baseload operation to realize favourable economics, but at high IRE penetrations, BC plants must be operated at low capacity factors. A H2-BC strategy is a promising way to address this challenge. The elements of a H2-BC system are: (a) H2 production from carbonaceous feedstocks in baseload plants with CCS; (b) H2 consumption in fast-ramping BC units that operate at low capacity factors; (c) Buffer underground H2 storage to enable decoupling baseload H2 production from highly variable H2 consumption by BC units. The concept is likely to "work" because underground H2 storage is expected to be inexpensive. A H2 production analysis is presented for a negative GHG-emitting H2-BC system based on cogasification of corn stover and coal, with captured CO2 used for enhanced oil recovery. The technical readiness of each system component is discussed, and preliminary insights are offered as to the conditions under which the corresponding H2-BC system might compete with natural gas in providing backup for IRE on US electric grids. Public policy to help advance this strategy might be forthcoming, because 2 US Senate bills with broad

  9. Structural Analysis of PTM Hotspots (SAPH-ire) – A Quantitative Informatics Method Enabling the Discovery of Novel Regulatory Elements in Protein Families*

    Science.gov (United States)

    Dewhurst, Henry M.; Choudhury, Shilpa; Torres, Matthew P.

    2015-01-01

    Predicting the biological function potential of post-translational modifications (PTMs) is becoming increasingly important in light of the exponential increase in available PTM data from high-throughput proteomics. We developed structural analysis of PTM hotspots (SAPH-ire)—a quantitative PTM ranking method that integrates experimental PTM observations, sequence conservation, protein structure, and interaction data to allow rank order comparisons within or between protein families. Here, we applied SAPH-ire to the study of PTMs in diverse G protein families, a conserved and ubiquitous class of proteins essential for maintenance of intracellular structure (tubulins) and signal transduction (large and small Ras-like G proteins). A total of 1728 experimentally verified PTMs from eight unique G protein families were clustered into 451 unique hotspots, 51 of which have a known and cited biological function or response. Using customized software, the hotspots were analyzed in the context of 598 unique protein structures. By comparing distributions of hotspots with known versus unknown function, we show that SAPH-ire analysis is predictive for PTM biological function. Notably, SAPH-ire revealed high-ranking hotspots for which a functional impact has not yet been determined, including phosphorylation hotspots in the N-terminal tails of G protein gamma subunits—conserved protein structures never before reported as regulators of G protein coupled receptor signaling. To validate this prediction we used the yeast model system for G protein coupled receptor signaling, revealing that gamma subunit–N-terminal tail phosphorylation is activated in response to G protein coupled receptor stimulation and regulates protein stability in vivo. These results demonstrate the utility of integrating protein structural and sequence features into PTM prioritization schemes that can improve the analysis and functional power of modification-specific proteomics data. PMID:26070665

  10. Beam Simulations for IRE and Driver-Status and Strategy

    International Nuclear Information System (INIS)

    Friedman, A.; Grote, D.P.; Lee, E.P.; Sonnendrucker, E.

    2000-01-01

    The methods and codes employed in the U.S. Heavy Ion Fusion program to simulate the beams in an Integrated Research Experiments (IRE) facility and a fusion driver are presented in overview. A new family of models incorporating accelerating module impedance, multi-beam, and self-magnetic effects is described, and initial WARP3d particle simulations of beams using these models are presented. Finally, plans for streamlining the machine-design simulation sequence, and for simulating beam dynamics from the source to the target in a consistent and comprehensive manner, are described

  11. Irreversible Electroporation (IRE) Fails to Demonstrate Efficacy in a Prospective Multicenter Phase II Trial on Lung Malignancies: The ALICE Trial

    Energy Technology Data Exchange (ETDEWEB)

    Ricke, Jens, E-mail: jens.ricke@med.ovgu.de; Jürgens, Julian H. W., E-mail: julian.juergens@med.ovgu.de [University of Magdeburg, Department of Radiology and Nuclear Medicine (Germany); Deschamps, Frederic; Tselikas, Lambros [Institut de Cancérologie Gustave Roussy, Department of Image Guided Therapy (France); Uhde, Katja; Kosiek, Ortrud [University of Magdeburg, Department of Radiology and Nuclear Medicine (Germany); Baere, Thierry De [Institut de Cancérologie Gustave Roussy, Department of Image Guided Therapy (France)

    2015-04-15

    PurposeTo assess safety and efficacy of irreversible electroporation (IRE) of lung malignancies.Materials and MethodsPatients with primary and secondary lung malignancies and preserved lung function were included in this prospective single arm trial. Primary and secondary endpoints were safety and efficacy. Recruitment goal was 36 subjects in 2 centers. Patients underwent IRE under general anesthesia with probe placement performed in Fluoroscopy-CT. The IRE system employed was NanoKnife{sup ®} (Angiodynamics). System settings for the ablation procedure followed the manufacturer’s recommendations. The Mann–Whitney U test was used to evaluate the correlation of nine technical parameters with local tumor control. Median follow up was 12 months.ResultsThe expected efficacy was not met at interim analysis and the trial was stopped prematurely after inclusion of 23 patients (13/10 between both centers). The dominant tumor entity was colorectal (n = 13). The median tumor diameter was 16 mm (8–27 mm). Pneumothoraces were observed in 11 of 23 patients with chest tubes required in 8 (35 %). Frequently observed alveolar hemorrhage never led to significant hemoptysis. 14/23 showed progressive disease (61 %). Stable disease was found in 1 (4 %), partial remission in 1 (4 %) and complete remission in 7 (30 %) patients. The relative increase of the current during ablation was significantly higher in the group treated successfully as compared to the group presenting local recurrence (p < 0.05). Needle tract seeding was found in three cases (13 %).ConclusionsIRE is not effective for the treatment of lung malignancies. We hypothesize that the energy deposition with current IRE probes is highly sensitive to air exposure.

  12. Ribosome stalling regulates IRES-mediated translation in eukaryotes, a parallel to prokaryotic attenuation

    NARCIS (Netherlands)

    Fernandez, James; Yaman, Ibrahim; Huang, Charles; Liu, Haiyan; Lopez, Alex B.; Komar, Anton A.; Caprara, Mark G.; Merrick, William C.; Snider, Martin D.; Kaufman, Randal J.; Lamers, Wouter H.; Hatzoglou, Maria

    2005-01-01

    It was previously shown that the mRNA for the cat-1 Arg/Lys transporter is translated from an internal ribosome entry site (IRES) that is regulated by cellular stress. Amino acid starvation stimulated cat-1 translation via a mechanism that requires translation of an ORF in the mRNA leader and

  13. Increased expression of IRE1α and stress-related signal transduction proteins in ischemia-reperfusion injured retina

    Directory of Open Access Journals (Sweden)

    Natsuyo Hata

    2008-08-01

    Full Text Available Natsuyo Hata1, Toshiyuki Oshitari1,2, Akiko Yokoyama1,3, Yoshinori Mitamura1, Shuichi Yamamoto11Department of Ophthalmology and Visual Science, Chiba University Graduate School of Medicine, Chuo-ku, Chiba, Japan; 2Department of Ophthalmology, Kimitsu Central Hospital, Kisarazu City, Chiba, Japan; 3Department of Ophthalmology, Inoue Memorial Hospital, Chuo-ku, Chiba, JapanAbstract: The purpose of this study was to determine whether the expression of ER stress-related factors IRE1α, apoptosis signal-regulating kinase 1 (ASK1, SAPK/ERK kinase 1 (SEK1 and c-Jun N-terminal kinase (JNK is associated with the damaged retinal neurons induced by ischemia-reperfusion injury. After 60 minutes of ischemia, the rat retinas were reperfused, and retinas were isolated and fixed after 6, 9, 12, 18, and 24 hours, and 2, 5, and 9 days of reperfusion. Cryosections were immunostained with Fluoro-Jade B, a degenerating neuron marker to label degenerating neurons. Semi-quantitative analysis of the expression of IRE1α, ASK1, SEK1, and JNK were performed in both control and ischemic retinas. In ischemic retinas, the intensities of IRE1α immunoreactivity in the ganglion cell layer (GCL were significantly higher than in the control retinas. In ischemic retinas, the numbers of SEK1-, ASK1-, and JNK-positive cells were significantly increased in the GCL compared to those in the control retinas. In addition, the cells that were positive for SEK1-, ASK1-, and JNK were also positive for Fluoro-Jade B-positive cells. These results indicate that the increased expression of ER stress-related factors was, in part, associated with the retinal neuronal abnormalities after ischemia-reperfusion injury in rat retinas.Keywords: endoplasmic reticulum, IRE1α, apoptosis signal-regulating kinase 1, SAPK/ERK kinase 1, c-Jun N-terminal kinase, Fluoro-Jade B, ischemia-reperfusion injury

  14. Multivesicular body formation enhancement and exosome release during endoplasmic reticulum stress.

    Science.gov (United States)

    Kanemoto, Soshi; Nitani, Ryota; Murakami, Tatsuhiko; Kaneko, Masayuki; Asada, Rie; Matsuhisa, Koji; Saito, Atsushi; Imaizumi, Kazunori

    2016-11-11

    The endoplasmic reticulum (ER) plays a pivotal role in maintaining cellular homeostasis. However, numerous environmental and genetic factors give rise to ER stress by inducing an accumulation of unfolded proteins. Under ER stress conditions, cells initiate the unfolded protein response (UPR). Here, we demonstrate a novel aspect of the UPR by electron microscopy and immunostaining analyses, whereby multivesicular body (MVB) formation was enhanced after ER stress. This MVB formation was influenced by inhibition of ER stress transducers inositol required enzyme 1 (IRE1) and PKR-like ER kinase (PERK). Furthermore, exosome release was also increased during ER stress. However, in IRE1 or PERK deficient cells, exosome release was not upregulated, indicating that IRE1- and PERK-mediated pathways are involved in ER stress-dependent exosome release. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Biomonitoring of intermittent rivers and ephemeral streams in Europe: Current practice and priorities to enhance ecological status assessments.

    Science.gov (United States)

    Stubbington, Rachel; Chadd, Richard; Cid, Núria; Csabai, Zoltán; Miliša, Marko; Morais, Manuela; Munné, Antoni; Pařil, Petr; Pešić, Vladimir; Tziortzis, Iakovos; Verdonschot, Ralf C M; Datry, Thibault

    2018-03-15

    Intermittent rivers and ephemeral streams (IRES) are common across Europe and dominate some Mediterranean river networks. In all climate zones, IRES support high biodiversity and provide ecosystem services. As dynamic ecosystems that transition between flowing, pool, and dry states, IRES are typically poorly represented in biomonitoring programmes implemented to characterize EU Water Framework Directive ecological status. We report the results of a survey completed by representatives from 20 European countries to identify current challenges to IRES status assessment, examples of best practice, and priorities for future research. We identify five major barriers to effective ecological status classification in IRES: 1. the exclusion of IRES from Water Framework Directive biomonitoring based on their small catchment size; 2. the lack of river typologies that distinguish between contrasting IRES; 3. difficulties in defining the 'reference conditions' that represent unimpacted dynamic ecosystems; 4. classification of IRES ecological status based on lotic communities sampled using methods developed for perennial rivers; and 5. a reliance on taxonomic characterization of local communities. Despite these challenges, we recognize examples of innovative practice that can inform modification of current biomonitoring activity to promote effective IRES status classification. Priorities for future research include reconceptualization of the reference condition approach to accommodate spatiotemporal fluctuations in community composition, and modification of indices of ecosystem health to recognize both taxon-specific sensitivities to intermittence and dispersal abilities, within a landscape context. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  16. Back to basics: the untreated rabbit reticulocyte lysate as a competitive system to recapitulate cap/poly(A) synergy and the selective advantage of IRES-driven translation.

    Science.gov (United States)

    Soto Rifo, Ricardo; Ricci, Emiliano P; Décimo, Didier; Moncorgé, Olivier; Ohlmann, Théophile

    2007-01-01

    Translation of most eukaryotic mRNAs involves the synergistic action between the 5' cap structure and the 3' poly(A) tail at the initiation step. The poly(A) tail has also been shown to stimulate translation of picornavirus internal ribosome entry sites (IRES)-directed translation. These effects have been attributed principally to interactions between eIF4G and poly(A)-binding protein (PABP) but also to the participation of PABP in other steps during translation initiation. As the rabbit reticulocyte lysate (RRL) does not recapitulate this cap/poly(A) synergy, several systems based on cellular cell-free extracts have been developed to study the effects of poly(A) tail in vitro but they generally exhibit low translational efficiency. Here, we describe that the non-nuclease-treated RRL (untreated RRL) is able to recapitulate the effects of poly(A) tail on translation in vitro. In this system, translation of a capped/polyadenylated RNA was specifically inhibited by either Paip2 or poly(rA), whereas translation directed by HCV IRES remained unaffected. Moreover, cleavage of eIF4G by FMDV L protease strongly stimulated translation directed by the EMCV IRES, thus recapitulating the competitive advantage that the proteolytic processing of eIF4G confers to IRES-driven RNAs.

  17. The multi-targeted kinase inhibitor sorafenib inhibits enterovirus 71 replication by regulating IRES-dependent translation of viral proteins.

    Science.gov (United States)

    Gao, Meng; Duan, Hao; Liu, Jing; Zhang, Hao; Wang, Xin; Zhu, Meng; Guo, Jitao; Zhao, Zhenlong; Meng, Lirong; Peng, Yihong

    2014-06-01

    The activation of ERK and p38 signal cascade in host cells has been demonstrated to be essential for picornavirus enterovirus 71 (EV71) replication and up-regulation of virus-induced cyclooxygenase-2 (COX-2)/prostaglandins E2 (PGE2) expression. The aim of this study was to examine the effects of sorafenib, a clinically approved anti-cancer multi-targeted kinase inhibitor, on the propagation and pathogenesis of EV71, with a view to its possible mechanism and potential use in the design of therapy regimes for Hand foot and mouth disease (HFMD) patients with life threatening neurological complications. In this study, non-toxic concentrations of sorafenib were shown to inhibit the yield of infectious progeny EV71 (clinical BC08 strain) by about 90% in three different cell types. A similar inhibitory effect of sorafenib was observed on the synthesis of both viral genomic RNA and the VP1 protein. Interestingly, sorafenib exerted obvious inhibition of the EV71 internal ribosomal entry site (IRES)-mediated translation, the first step in picornavirus replication, by linking it to a firefly luciferase reporter gene. Sorafenib was also able to prevent both EV71-induced CPE and the activation of ERK and p38, which contributes to up-regulation COX-2/PGE2 expression induced by the virus. Overall, this study shows that sorafenib strongly inhibits EV71 replication at least in part by regulating viral IRES-dependent translation of viral proteins, indicating a novel potential strategy for the treatment of HFMD patients with severe neurological complications. To our knowledge, this is the first report that investigates the mechanism by which sorafenib inhibits EV71 replication. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Reliability and responsiveness of dynamic contrast-enhanced magnetic resonance imaging in rheumatoid arthritis

    DEFF Research Database (Denmark)

    Axelsen, M.B.; Poggenborg, R.P.; Stoltenberg, M.

    2013-01-01

    intraarticular injection with 80 mg methylprednisolone. Using semi-automated image processing software, DCE-MRI parameters, including the initial rate of enhancement (IRE) and maximal enhancement (ME), were generated for three regions of interest (ROIs): ‘Whole slice’, ‘Quick ROI’, and ‘Precise ROI......Objectives: To investigate the responsiveness to treatment and the reliability of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) in rheumatoid arthritis (RA) knee joints. Methods: DCE-MRI was performed in 12 clinically active RA knee joints before and 1, 7, 30, and 180 days after......’. The smallest detectable difference (SDD), the smallest detectable change (SDC), and intra- and inter-reader intraclass correlation coefficients (ICCs) were used to assess the reliability of DCE-MRI. Responsiveness to treatment was assessed by the standardized response mean (SRM). Results: In all patients...

  19. Insight into the recognition, binding, and reactivity of catalytic metallodrugs targeting stem loop IIb of hepatitis C IRES RNA.

    Science.gov (United States)

    Bradford, Seth S; Ross, Martin James; Fidai, Insiya; Cowan, James A

    2014-06-01

    The complex Cu-GGHYrFK-amide (1-Cu) was previously reported as a novel metallotherapeutic that catalytically inactivates stem loop IIb (SLIIb) of the hepatitis C virus (HCV) internal ribosomal entry site (IRES) RNA and demonstrates significant antiviral activity in a cellular HCV replicon assay. Herein we describe additional studies focused on understanding the cleavage mechanism as well as the relationship of catalyst configuration to structural recognition and site-selective cleavage of the structured RNA motif. These are advanced by use of a combination of MALDI-TOF mass spectrometry, melting temperature determinations, and computational analysis to develop a structural model for binding and reactivity toward SLIIb of the IRES RNA. In addition, the binding, reactivity, and structural chemistry of the all-D-amino acid form of this metallopeptide, complex 2-Cu, are reported and compared with those of complex 1-Cu. In vitro RNA binding and cleavage assays for complex 2-Cu show a KD value of 76 ± 3 nM, and Michaelis-Menten parameters of kcat =0.14 ± 0.01 min(-1) and KM =7.9 ± 1.2 μM, with a turnover number exceeding 40. In a luciferase-based cellular replicon assay Cu-GGhyrfk-amide shows activity similar to that of the 1-Cu parent peptide, with an IC50 value of 1.9 ± 0.4 μM and cytotoxicity exceeding 100 μM. RT-PCR experiments confirm a significant decrease in HCV RNA levels in replicon assays for up to nine days when treated with complex 1-Cu in three-day dosing increments. This study shows the influence that the α-carbon stereocenter has for this new class of compounds, while detailed mass spectrometry and computational analyses provide new insight into the mechanisms of recognition, binding, and reactivity. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. The IRP/IRE system in vivo: insights from mouse models

    Directory of Open Access Journals (Sweden)

    Nicole eWilkinson

    2014-07-01

    Full Text Available Iron regulatory proteins 1 and 2 (IRP1 and IRP2 post-transcriptionally control the expression of several mRNAs encoding proteins of iron, oxygen and energy metabolism. The mechanism involves their binding to iron responsive elements (IREs in the untranslated regions of target mRNAs, thereby controlling mRNA translation or stability. Whereas IRP2 functions solely as an RNA-binding protein, IRP1 operates as either an RNA-binding protein or a cytosolic aconitase. Early experiments in cultured cells established a crucial role of IRPs in regulation of cellular iron metabolism. More recently, studies in mouse models with global or localized Irp1 and/or Irp2 deficiencies uncovered new physiological functions of IRPs in the context of systemic iron homeostasis. Thus, IRP1 emerged as a key regulator of erythropoiesis and iron absorption by controlling hypoxia inducible factor 2α (HIF2α mRNA translation, while IRP2 appears to dominate the control of iron uptake and heme biosynthesis in erythroid progenitor cells by regulating the expression of transferrin receptor 1 (TfR1 and 5-aminolevulinic acid synthase 2 (ALAS2 mRNAs, respectively. Targeted disruption of either Irp1 or Irp2 in mice is associated with distinct phenotypic abnormalities. Thus, Irp1-/- mice develop polycythemia and pulmonary hypertension, while Irp2-/- mice present with microcytic anemia, iron overload in the intestine and the liver, and neurologic defects. Combined disruption of both Irp1 and Irp2 is incombatible with life and leads to early embryonic lethality. Mice with intestinal- or liver-specific disruption of both Irps are viable at birth but die later on due to malabsorption or liver failure, respectively. Adult mice lacking both Irps in the intestine exhibit a profound defect in dietary iron absorption due to a mucosal block that is caused by the de-repression of ferritin mRNA translation. Herein, we discuss the physiological function of the IRE/IRP regulatory system.

  1. Roles of different IRES-dependent FGF2 isoforms in the acquisition of the major aggressive features of human metastatic melanoma.

    Science.gov (United States)

    Andreucci, Elena; Bianchini, Francesca; Biagioni, Alessio; Del Rosso, Mario; Papucci, Laura; Schiavone, Nicola; Magnelli, Lucia

    2017-01-01

    Fibroblast growth factor 2 (FGF2) is involved in many physiological and pathological processes. Fgf2 deregulation contributes to the acquisition of malignant features of melanoma and other cancers. FGF2 is an alternative translation product expressed as five isoforms, a low-molecular-weight (18 KDa) and four high-molecular-weight (22, 22.5, 24, 34 KDa) isoforms, with different subcellular distributions. An internal ribosomal entry site (IRES) in its mRNA controls the translation of all the isoforms with the exception for the cap-dependent 34 KDa. The 18-KDa isoform has been extensively studied, while very few is known about the roles of high molecular weight isoforms. FGF2 is known to promote melanoma development and progression. To disclose the differential contribution of FGF2 isoforms in melanoma, we forced the expression of IRES-dependent low-molecular-weight (LMW, 18 KDa) and high-molecular-weight (HMW, 22, 22.5, 24 KDa) isoforms in a human metastatic melanoma cell line. This comparative study highlights that, while LMW isoform confers stem-like features to melanoma cells and promotes angiogenesis, HMW isoforms induce higher migratory ability and contribute to tumor perfusion by promoting vasculogenic mimicry (VM) when endothelial cell-driven angiogenesis is lacking. To conclude, FGF2 isoforms mainly behave in specific, antithetical manners, but can cooperate in different steps of tumor progression, providing melanoma cells with major malignant features. FGF2 is an alternative translation product expressed as different isoforms termed LMW and HMW. FGF2 is involved in melanoma development and progression. HMW FGF2 isoforms enhance in vitro motility of melanoma cells. LMW FGF2 confers stem-like features and increases in vivo metastasization. LMW FGF2 promotes angiogenesis while HMW FGF2 induces vasculogenic mimicry.

  2. A close connection between the PERK and IRE arms of the UPR and the transcriptional regulation of autophagy.

    Science.gov (United States)

    Deegan, Shane; Koryga, Izabela; Glynn, Sharon A; Gupta, Sanjeev; Gorman, Adrienne M; Samali, Afshin

    2015-01-02

    Endoplasmic reticulum (ER) stress is known to lead to activation of both the unfolded protein response (UPR) and autophagy. Although regulatory connections have been identified between the UPR and autophagy, it is still unclear to what extent the UPR regulates the genes involved at the different stages of the autophagy pathway. Here, we carried out a microarray analysis of HCT116 cells subjected to ER stress and observed the transcriptional upregulation of a large cohort of autophagy-related genes. Of particular interest, we identified the transcriptional upregulation of the autophagy receptor genes SQSTM1/p62, NBR1 and BNIP3L/NIX in response to ER stress and show that the inhibition of the UPR transmembrane receptors, PERK and IRE1, abrogates this upregulation. Copyright © 2014 Elsevier Inc. All rights reserved.

  3. Enhancing Irreversible Electroporation by Manipulating Cellular Biophysics with a Molecular Adjuvant.

    Science.gov (United States)

    Ivey, Jill W; Latouche, Eduardo L; Richards, Megan L; Lesser, Glenn J; Debinski, Waldemar; Davalos, Rafael V; Verbridge, Scott S

    2017-07-25

    Pulsed electric fields applied to cells have been used as an invaluable research tool to enhance delivery of genes or other intracellular cargo, as well as for tumor treatment via electrochemotherapy or tissue ablation. These processes involve the buildup of charge across the cell membrane, with subsequent alteration of transmembrane potential that is a function of cell biophysics and geometry. For traditional electroporation parameters, larger cells experience a greater degree of membrane potential alteration. However, we have recently demonstrated that the nuclear/cytoplasm ratio (NCR), rather than cell size, is a key predictor of response for cells treated with high-frequency irreversible electroporation (IRE). In this study, we leverage a targeted molecular therapy, ephrinA1, known to markedly collapse the cytoplasm of cells expressing the EphA2 receptor, to investigate how biophysical cellular changes resulting from NCR manipulation affect the response to IRE at varying frequencies. We present evidence that the increase in the NCR mitigates the cell death response to conventional electroporation pulsed-electric fields (∼100 μs), consistent with the previously noted size dependence. However, this same molecular treatment enhanced the cell death response to high-frequency electric fields (∼1 μs). This finding demonstrates the importance of considering cellular biophysics and frequency-dependent effects in developing electroporation protocols, and our approach provides, to our knowledge, a novel and direct experimental methodology to quantify the relationship between cell morphology, pulse frequency, and electroporation response. Finally, this novel, to our knowledge, combinatorial approach may provide a paradigm to enhance in vivo tumor ablation through a molecular manipulation of cellular morphology before IRE application. Copyright © 2017 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  4. Growth- and Stress-Induced PASTA Kinase Phosphorylation in Enterococcus faecalis.

    Science.gov (United States)

    Labbe, Benjamin D; Kristich, Christopher J

    2017-11-01

    Transmembrane Ser/Thr kinases containing extracellular PASTA domains are ubiquitous among Actinobacteria and Firmicutes Such PASTA kinases regulate critical processes, including antibiotic resistance, cell division, toxin production, and virulence, and are essential for viability in certain organisms. Based on in vitro studies with purified extracellular and intracellular fragments of PASTA kinases, a model for signaling has been proposed, in which the extracellular PASTA domains bind currently undefined ligands (typically thought to be peptidoglycan, or fragments thereof) to drive kinase dimerization, which leads to enhanced kinase autophosphorylation and enhanced phosphorylation of substrates. However, this model has not been rigorously tested in vivo Enterococcus faecalis is a Gram-positive intestinal commensal and major antibiotic-resistant opportunistic pathogen. In E. faecalis , the PASTA kinase IreK drives intrinsic resistance to cell wall-active antimicrobials, suggesting that such antimicrobials may trigger IreK signaling. Here we show that IreK responds to cell wall stress in vivo by enhancing its phosphorylation and that of a downstream substrate. This response requires both the extracellular PASTA domains and specific phosphorylatable residues in the kinase domain. Thus, our results provide in vivo evidence, with an intact full-length PASTA kinase in its native physiological environment, that supports the prevailing model of PASTA kinase signaling. In addition, we show that IreK responds to a signal associated with growth and/or cell division, in the absence of cell wall-active antimicrobials. Surprisingly, the ability of IreK to respond to growth and/or division does not require the extracellular PASTA domains, suggesting that IreK monitors multiple parameters for sensory input in vivo IMPORTANCE Transmembrane Ser/Thr kinases containing extracellular PASTA domains are ubiquitous among Actinobacteria and Firmicutes and regulate critical processes. The

  5. Sigma-1 receptor chaperone at the ER-mitochondrion interface mediates the mitochondrion-ER-nucleus signaling for cellular survival.

    Directory of Open Access Journals (Sweden)

    Tomohisa Mori

    Full Text Available The membrane of the endoplasmic reticulum (ER of a cell forms contacts directly with mitochondria whereby the contact is referred to as the mitochondrion-associated ER membrane or the MAM. Here we found that the MAM regulates cellular survival via an MAM-residing ER chaperone the sigma-1 receptor (Sig-1R in that the Sig-1R chaperones the ER stress sensor IRE1 to facilitate inter-organelle signaling for survival. IRE1 is found in this study to be enriched at the MAM in CHO cells. We found that IRE1 is stabilized at the MAM by Sig-1Rs when cells are under ER stress. Sig-1Rs stabilize IRE1 and thus allow for conformationally correct IRE1 to dimerize into the long-lasting, activated endonuclease. The IRE1 at the MAM also responds to reactive oxygen species derived from mitochondria. Therefore, the ER-mitochondrion interface serves as an important subcellular entity in the regulation of cellular survival by enhancing the stress-responding signaling between mitochondria, ER, and nucleus.

  6. Sigma-1 receptor chaperone at the ER-mitochondrion interface mediates the mitochondrion-ER-nucleus signaling for cellular survival.

    Science.gov (United States)

    Mori, Tomohisa; Hayashi, Teruo; Hayashi, Eri; Su, Tsung-Ping

    2013-01-01

    The membrane of the endoplasmic reticulum (ER) of a cell forms contacts directly with mitochondria whereby the contact is referred to as the mitochondrion-associated ER membrane or the MAM. Here we found that the MAM regulates cellular survival via an MAM-residing ER chaperone the sigma-1 receptor (Sig-1R) in that the Sig-1R chaperones the ER stress sensor IRE1 to facilitate inter-organelle signaling for survival. IRE1 is found in this study to be enriched at the MAM in CHO cells. We found that IRE1 is stabilized at the MAM by Sig-1Rs when cells are under ER stress. Sig-1Rs stabilize IRE1 and thus allow for conformationally correct IRE1 to dimerize into the long-lasting, activated endonuclease. The IRE1 at the MAM also responds to reactive oxygen species derived from mitochondria. Therefore, the ER-mitochondrion interface serves as an important subcellular entity in the regulation of cellular survival by enhancing the stress-responding signaling between mitochondria, ER, and nucleus.

  7. Accidental release of iodine 131 by the IRE of the Fleurus site: return on experience by the Belgian safety authority

    International Nuclear Information System (INIS)

    Vandecasteele, C.M.; Sonck, M.; Degueldre, D.

    2010-01-01

    After a presentation of the activities of the IRE, the Belgian National Institute of Radio-elements, i.e. the production of radionuclides used in nuclear medicine, this report describes the process and chemical reaction which caused an accidental release of iodine 131. It analyzes the causes of this incident, and how the incident has been managed by the Belgian safety authority. It discusses the first assessment of radiological consequences, describes how the incident has been managed at the federal level, and how population and media have been informed. It discusses the actual radiological consequences through measurements performed on grass and vegetables (graphs and maps indicate contamination levels and contaminated areas), and through the assessment of exposure of adults and children by different ways. Lessons learned are then discussed

  8. Tat-haFGF14–154 Upregulates ADAM10 to Attenuate the Alzheimer Phenotype of APP/PS1 Mice through the PI3K-CREB-IRE1α/XBP1 Pathway

    Directory of Open Access Journals (Sweden)

    Tian Meng

    2017-06-01

    Full Text Available Acid fibroblast growth factor (aFGF has shown neuroprotection in Alzheimer’s disease (AD models in previous studies, yet its mechanism is still uncertain. Here we report that the efficacy of Tat-haFGF14–154 is markedly increased when loaded cationic liposomes for intranasal delivery are intranasally administered to APP/PS1 mice. Our results demonstrated that liposomal Tat-haFGF14–154 treatment significantly ameliorated behavioral deficits, relieved brain Aβ burden, and increased the expression and activity of disintegrin and metalloproteinase domain-containing protein 10 (ADAM10 in the brain. Tat-haFGF14–154 antagonized Aβ1–42-induced cell death and structural damage in rat primary neurons in an ADAM10-dependent manner, which, in turn, was promoted by the activation of XBP1 splicing and modulated by the PI3K-CREB pathway. Both knockdown of ADAM10 and inhibition of PI3K (LY294002 negated Tat-haFGF14–154 rescue. Thus, Tat-haFGF14–154 activates the IRE1α/XBP1 pathway of the unfolded protein response (UPR against the endoplasmic reticulum (ER stress induced by Aβ, and, subsequently, the nuclear translocation of spliced XBP1 (XBP1s promotes transcription of ADAM10. These results highlight the important role of ADAM10 and its activation through the PI3K-CREB-IRE1α/XBP1 pathway as a key factor in the mechanism of neuroprotection for Tat-haFGF14–154.

  9. Evaluating automated dynamic contrast enhanced wrist 3 T MRI in healthy volunteers: One-year longitudinal observational study

    Energy Technology Data Exchange (ETDEWEB)

    Rastogi, Anshul, E-mail: anshul.rastogi@bartshealth.nhs.uk [Kennedy Institute of Rheumatology, Imperial College London (United Kingdom); Kubassova, Olga, E-mail: olga@imageanalysis.org.uk [Image Analysis, Leeds (United Kingdom); Krasnosselskaia, Lada V., E-mail: solaguz@yahoo.com [Imaging Sciences Department, Imperial College London (United Kingdom); Lim, Adrian K.P., E-mail: a.lim@imperial.ac.uk [Department of Radiology, Imperial College Healthcare NHS Trust, London (United Kingdom); Satchithananda, Keshthra, E-mail: keshthra.satchithananda@imperial.nhs.uk [Department of Radiology, Imperial College Healthcare NHS Trust, London (United Kingdom); Boesen, Mikael, E-mail: mikael.boesen@gmail.com [Department of Radiology and the Parker Institute, Frederiksberg and Bispebjerg Hospitals (Denmark); Binks, Michael, E-mail: michael.h.binks@gsk.com [GlaxoSmithKline, Stevenage, SG1 2NY (United Kingdom); Hajnal, Joseph V., E-mail: jo.hajnal@kcl.ac.uk [Imaging Sciences Department, Imperial College London (United Kingdom); Taylor, Peter C., E-mail: peter.taylor@kennedy.ox.ac.uk [Kennedy Institute of Rheumatology, Imperial College London (United Kingdom)

    2013-08-15

    Rational and Objective: Dynamic contrast enhanced (DCE)-MRI has great potential to provide quantitative measure of inflammatory activity in rheumatoid arthritis. There is no current benchmark to establish the stability of signal in the joints of healthy subjects when imaged with DCE-MRI longitudinally, which is crucial so as to differentiate changes induced by treatment from the inherent variability of perfusion measures. The objective of this study was to test a pixel-by-pixel parametric map based approach for analysis of DCE-MRI (Dynamika) and to investigate the variability in signal characteristics over time in healthy controls using longitudinally acquired images. Materials and Methods: 10 healthy volunteers enrolled, dominant wrists were imaged with contrast enhanced 3T MRI at baseline, week 12, 24 and 52 and scored with RAMRIS, DCE-MRI was analysed using a novel quantification parametric map based approach. Radiographs were obtained at baseline and week 52 and scored using modified Sharp van der Heidje method. RAMRIS scores and dynamic MRI measures were correlated. Results: No erosions were seen on radiographs, whereas MRI showed erosion-like changes, low grade bone marrow oedema and low-moderate synovial enhancement. The DCE-MRI parameters were stable (baseline scores, variability) (mean ± st.dev); in whole wrist analysis, ME{sub mean} (1.3 ± 0.07, −0.08 ± 0.1 at week 24) and IRE{sub mean} (0.008 ± 0.004, −0.002 ± 0.005 at week 12 and 24). In the rough wrist ROI, ME{sub mean} (1.2 ± 0.07, 0.04 ± 0.02 at week 52) and IRE{sub mean} (0.001 ± 0.0008, 0.0006 ± 0.0009 at week 52) and precise wrist ROI, ME{sub mean} (1.2 ± 0.09, 0.04 ± 0.04 at week 52) and IRE{sub mean} (0.001 ± 0.0008, 0.0008 ± 0.001 at week 24 and 52). The Dynamic parameters obtained using fully automated analysis demonstrated strong, statistically significant correlations with RAMRIS synovitis scores. Conclusion: The study demonstrated that contrast enhancement does occur in

  10. Regulation of translation during cancer progression

    International Nuclear Information System (INIS)

    Petz, M.

    2012-01-01

    Laminin B1 (LamB1) is a main component of the extracellular matrix and is involved in the regulation of tumor cell migration and invasion of during carcinogenesis. Metastasis of carcinoma cells is crucially linked to the process of epithelial to mesenchymal transition (EMT), which allows tumor cells to acquire a more motile phenotype and to dissociate from the epithelial cell cluster of the tumor. Expression profiling of polysome-associated mRNA revealed LamB1 to be translationally upregulated upon EMT of malignant hepatocytes. The enhanced translation of LamB1 in metastatic hepatocytes proved to be regulated by an internal ribosome entry site (IRES) located within the 5’-untranslated region (UTR) of the LamB1 transcript. IRES activity was detected by employing two independent reporter systems and verified by stringent assays for the presence of cryptic promoter or splice sites. The minimal cis-acting IRES sequence of 293 nucleotides that is required for cap-independent translation was localized directly upstream of the start codon. Notably, the IRES trans-acting factor (ITAF) La was identified by RNA affinity purification as regulatory factor that interacts with LamB1 5’-UTR. This interaction was verified by RNA-immunoprecipitation in vivo, which revealed enhanced binding of La to the minimal IRES motif of LamB1 after EMT. Consistently, cytoplasmic levels of La were elevated in EMT-transformed cells and correlated with increased LamB1 protein expression. Furthermore, IRES-driven translation of LamB1 was elevated in the presence of La in vitro. Importantly, the EMT-induced cytoplasmic translocation of La was found to be triggered by platelet derived growth factor (PDGF) that is downstream of transforming growth factor (TGF)-β signaling. Together, these data demonstrate that La interacts with the LamB1 IRES in the cytoplasm, resulting in enhanced cap-independent translation of LamB1 in malignant hepatocytes that have undergone EMT. (author) [de

  11. Somatostatin-IRES-Cre Mice: Between Knockout and Wild-Type?

    Science.gov (United States)

    Viollet, Cécile; Simon, Axelle; Tolle, Virginie; Labarthe, Alexandra; Grouselle, Dominique; Loe-Mie, Yann; Simonneau, Michel; Martel, Guillaume; Epelbaum, Jacques

    2017-01-01

    The neuropeptide somatostatin (SOM) is widely expressed in rodent brain and somatostatin-IRES-Cre (SOM-cre) mouse strains are increasingly used to unravel the physiology of SOM-containing neurons. However, while knock-in targeting strategy greatly improves Cre-Lox system accuracy, recent reports have shown that genomic insertion of Cre construct per se can markedly affect physiological function. We show that Cre transgene insertion into the 3'UTR of the somatostatin gene leads to the selective and massive depletion of endogenous SOM in all tested brain regions. It also strongly impacts SOM-related neuroendocrine responses in a similar manner to what has been reported for SST KO mice: increased corticosterone levels after 30-min restraint stress, decreased amplitude and regularity of ultradian growth hormone secretory patterns accompanied by changes in sexually dimorphic liver gene expression ( serpina1, Cyp2b9, Cyp2a4, Cyp2d9, and Cyp7b1 ). In addition to demonstrating the need for examination of the consequences of Cre transgenesis, these results also reveal how this SOM-cre strain may be a useful tool in studying the functional consequences of moderate to low SOM levels as reported in neurological and psychiatric disorders.

  12. Isikult vabaduse võtmine põhjendusel, et ta on psüühikahäire tõttu endale või teistele ohtlik / Sten Lind, Katrin Eino

    Index Scriptorium Estoniae

    Lind, Sten, 1979-

    2014-01-01

    Psüühikahäire määratlemine ning isiku ohtlikkus psühhiaatrilise abi seaduse § 11, sotsiaalhoolekande seaduse § 19 ja karistusseadustiku § 86 kontekstis. Riigikohtu lahenditest 3-2-1-81-07 ja 3-2-1-155-13

  13. Induction of viral, 7-methyl-guanosine cap-independent translation and oncolysis by mitogen-activated protein kinase-interacting kinase-mediated effects on the serine/arginine-rich protein kinase.

    Science.gov (United States)

    Brown, Michael C; Bryant, Jeffrey D; Dobrikova, Elena Y; Shveygert, Mayya; Bradrick, Shelton S; Chandramohan, Vidyalakshmi; Bigner, Darell D; Gromeier, Matthias

    2014-11-01

    Protein synthesis, the most energy-consuming process in cells, responds to changing physiologic priorities, e.g., upon mitogen- or stress-induced adaptations signaled through the mitogen-activated protein kinases (MAPKs). The prevailing status of protein synthesis machinery is a viral pathogenesis factor, particularly for plus-strand RNA viruses, where immediate translation of incoming viral RNAs shapes host-virus interactions. In this study, we unraveled signaling pathways centered on the ERK1/2 and p38α MAPK-interacting kinases MNK1/2 and their role in controlling 7-methyl-guanosine (m(7)G) "cap"-independent translation at enterovirus type 1 internal ribosomal entry sites (IRESs). Activation of Raf-MEK-ERK1/2 signals induced viral IRES-mediated translation in a manner dependent on MNK1/2. This effect was not due to MNK's known functions as eukaryotic initiation factor (eIF) 4G binding partner or eIF4E(S209) kinase. Rather, MNK catalytic activity enabled viral IRES-mediated translation/host cell cytotoxicity through negative regulation of the Ser/Arg (SR)-rich protein kinase (SRPK). Our investigations suggest that SRPK activity is a major determinant of type 1 IRES competency, host cell cytotoxicity, and viral proliferation in infected cells. We are targeting unfettered enterovirus IRES activity in cancer with PVSRIPO, the type 1 live-attenuated poliovirus (PV) (Sabin) vaccine containing a human rhinovirus type 2 (HRV2) IRES. A phase I clinical trial of PVSRIPO with intratumoral inoculation in patients with recurrent glioblastoma (GBM) is showing early promise. Viral translation proficiency in infected GBM cells is a core requirement for the antineoplastic efficacy of PVSRIPO. Therefore, it is critically important to understand the mechanisms controlling viral cap-independent translation in infected host cells. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  14. Modulation of mitogen-activated protein kinase-activated protein kinase 3 by hepatitis C virus core protein

    DEFF Research Database (Denmark)

    Ngo, HT; Pham, Long; Kim, JW

    2013-01-01

    Hepatitis C virus (HCV) is highly dependent on cellular proteins for its own propagation. In order to identify the cellular factors involved in HCV propagation, we performed protein microarray assays using the HCV core protein as a probe. Of ~9,000 host proteins immobilized in a microarray...... inducers. Binding of HCV core to MAPKAPK3 was confirmed by in vitro pulldown assay and further verified by coimmunoprecipitation assay. HCV core protein interacted with MAPKAPK3 through amino acid residues 41 to 75 of core and the N-terminal half of kinase domain of MAPKAPK3. In addition, both RNA...... increased HCV IRES-mediated translation and MAPKAPK3-dependent HCV IRES activity was further increased by core protein. These data suggest that HCV core may modulate MAPKAPK3 to facilitate its own propagation....

  15. Fasting exacerbates hepatic growth differentiation factor 15 to promote fatty acid β-oxidation and ketogenesis via activating XBP1 signaling in liver

    Directory of Open Access Journals (Sweden)

    Meiyuan Zhang

    2018-06-01

    Full Text Available Liver coordinates a series of metabolic adaptations to maintain systemic energy balance and provide adequate nutrients for critical organs, tissues and cells during starvation. However, the mediator(s implicated in orchestrating these fasting-induced adaptive responses and the underlying molecular mechanisms are still obscure. Here we show that hepatic growth differentiation factor 15 (GDF15 is regulated by IRE1α-XBP1s branch and promotes hepatic fatty acids β-oxidation and ketogenesis upon fasting. GDF15 expression was exacerbated in liver of mice subjected to long-term fasted or ketogenic diet feeding. Abrogation of hepatic Gdf15 dramatically attenuated hepatic β-oxidation and ketogenesis in fasted mice or mice with STZ-initiated type I diabetes. Further study revealed that XBP1s activated Gdf15 transcription via binding to its promoter. Elevated GDF15 in liver reduced lipid accumulation and impaired NALFD development in obese mice through enhancing fatty acids oxidation in liver. Therefore, our results demonstrate a novel and critical role of hepatic GDF15 activated by IRE1α-XBP1s branch in regulating adaptive responses of liver upon starvation stress. Keywords: Fasting, Fatty acid β-oxidation, Ketogenesis, GDF15, XBP1, NAFLD

  16. Establishment and Application of a High Throughput Screening System Targeting the Interaction between HCV Internal Ribosome Entry Site and Human Eukaryotic Translation Initiation Factor 3

    Directory of Open Access Journals (Sweden)

    Yuying Zhu

    2017-05-01

    Full Text Available Viruses are intracellular obligate parasites and the host cellular machinery is usually recruited for their replication. Human eukaryotic translation initiation factor 3 (eIF3 could be directly recruited by the hepatitis C virus (HCV internal ribosome entry site (IRES to promote the translation of viral proteins. In this study, we establish a fluorescence polarization (FP based high throughput screening (HTS system targeting the interaction between HCV IRES and eIF3. By screening a total of 894 compounds with this HTS system, two compounds (Mucl39526 and NP39 are found to disturb the interaction between HCV IRES and eIF3. And these two compounds are further demonstrated to inhibit the HCV IRES-dependent translation in vitro. Thus, this HTS system is functional to screen the potential HCV replication inhibitors targeting human eIF3, which is helpful to overcome the problem of viral resistance. Surprisingly, one compound HP-3, a kind of oxytocin antagonist, is discovered to significantly enhance the interaction between HCV IRES and eIF3 by this HTS system. HP-3 is demonstrated to directly interact with HCV IRES and promote the HCV IRES-dependent translation both in vitro and in vivo, which strongly suggests that HP-3 has potentials to promote HCV replication. Therefore, this HTS system is also useful to screen the potential HCV replication enhancers, which is meaningful for understanding the viral replication and screening novel antiviral drugs. To our knowledge, this is the first HTS system targeting the interaction between eIF3 and HCV IRES, which could be applied to screen both potential HCV replication inhibitors and enhancers.

  17. Dynamic contrast-enhanced, extremity-dedicated MRI identifies synovitis changes in the follow-up of rheumatoid arthritis patients treated with rituximab

    DEFF Research Database (Denmark)

    Cimmino, Marco A; Parodi, Massimiliano; Zampogna, Giuseppe

    2014-01-01

    according to the 1987 ACR criteria were treated with a single course of RTX (2 infusions of 1000 mg, 15 days apart). MRI of the dominant hand was performed with a 0.2T extremity-dedicated machine using pre and post contrast T1 weighted SE, turbo 3D, and STIR sequences at baseline, and after 4 and 24 weeks....... MRI was analysed using the OMERACT-RAMRIS score and the dynamic contrast-enhanced (DCE-MRI) technique for wrist synovitis, which calculates the enhancement ratio as both rate of early enhancement (REE) and relative enhancement (RE). The corresponding ME and IRE parameters were calculated also through...

  18. La importancia de los proyectos y redes innovadoras para el avance de la Enseñanza de las Ciencias: El caso de un profesor de la Red IRES

    Directory of Open Access Journals (Sweden)

    Gabriela Delord

    2017-01-01

    Full Text Available Este articulo presenta la descripción y análisis del Modelo de Investigación en la Escuela que fundamenta el Proyecto IRES (Investigación y Renovación Escolar y el análisis en profundidad de una entrevista a un maestro en el área de ciencias que pertenece a la red de este proyecto: Red IRES. Los resultados ponen en evidencia la importancia que ha tenido para este profesor la pertenencia al proyecto y al colectivo de docentes que lo impulsan, así como la pertinencia del modelo para sustentar los cambios introducidos en el aula. Destaca también la relevancia, para su evolución profesional, del diálogo entre docentes de todos los niveles del sistema educativo, incluida la universidad. Proponemos que estas experiencias sean más reconocidas y valoradas en el ámbito de la Enseñanza de las Ciencias y en las instancias gubernamentales.

  19. Nuclear Protein Sam68 Interacts with the Enterovirus 71 Internal Ribosome Entry Site and Positively Regulates Viral Protein Translation.

    Science.gov (United States)

    Zhang, Hua; Song, Lei; Cong, Haolong; Tien, Po

    2015-10-01

    Enterovirus 71 (EV71) recruits various cellular factors to assist in the replication and translation of its genome. Identification of the host factors involved in the EV71 life cycle not only will enable a better understanding of the infection mechanism but also has the potential to be of use in the development of antiviral therapeutics. In this study, we demonstrated that the cellular factor 68-kDa Src-associated protein in mitosis (Sam68) acts as an internal ribosome entry site (IRES) trans-acting factor (ITAF) that binds specifically to the EV71 5' untranslated region (5'UTR). Interaction sites in both the viral IRES (stem-loops IV and V) and the heterogeneous nuclear ribonucleoprotein K homology (KH) domain of Sam68 protein were further mapped using an electrophoretic mobility shift assay (EMSA) and biotin RNA pulldown assay. More importantly, dual-luciferase (firefly) reporter analysis suggested that overexpression of Sam68 positively regulated IRES-dependent translation of virus proteins. In contrast, both IRES activity and viral protein translation significantly decreased in Sam68 knockdown cells compared with the negative-control cells treated with short hairpin RNA (shRNA). However, downregulation of Sam68 did not have a significant inhibitory effect on the accumulation of the EV71 genome. Moreover, Sam68 was redistributed from the nucleus to the cytoplasm and interacts with cellular factors, such as poly(rC)-binding protein 2 (PCBP2) and poly(A)-binding protein (PABP), during EV71 infection. The cytoplasmic relocalization of Sam68 in EV71-infected cells may be involved in the enhancement of EV71 IRES-mediated translation. Since Sam68 is known to be a RNA-binding protein, these results provide direct evidence that Sam68 is a novel ITAF that interacts with EV71 IRES and positively regulates viral protein translation. The nuclear protein Sam68 is found as an additional new host factor that interacts with the EV71 IRES during infection and could potentially

  20. Accidental release of iodine-131 by IRE at Fleurus: back experience of Belgium safety authority; Rejet accidentel d'iode-131 par l'IRE sur le site de Fleurus: retour d'experience de l'autorite de surete belge

    Energy Technology Data Exchange (ETDEWEB)

    Vandecasteele, C.M.; Sonck, M. [AFCN - Agence federale de controle nucleaire, Bruxelles (Belgium); Degueldre, D. [Bel V, Anderlecht (Belgium)

    2011-04-15

    The IRE (National institute for radioelements) produces radionuclides for nuclear medicine from highly enriched uranium irradiated targets. On 22/08/2008, fresh production wastes were transferred into an almost empty decay tank. The mixing of these liquids led to the release of approximately 47 GBq of molecular iodine-131 into the atmosphere. The first conservative assessments of the radiological consequences did not require taking direct protective actions for the population, such as sheltering or stable iodine intake. However, the estimated iodine-131 deposits could locally reach or exceed the derived reference levels for the contamination of milk (4 kBq/m2) and leafy vegetables (10 kBq/m2). For this reason, and because there was a threat of a further release, the federal emergency plan was activated on 28/08 and the population potentially concerned was recommended to avoid consumption of locally produced fruits, vegetables and fresh milk. These protective actions were lifted on 7/09 and the emergency plan was lifted on 12/09. The main lesson learned from this event concerns the paramount importance of the rapid exchange of information that is as accurate and complete as possible between the different stakeholders: from the operator up to the population, through federal and local authorities. (authors)

  1. A La autoantigen homologue is required for the internal ribosome entry site mediated translation of giardiavirus.

    Directory of Open Access Journals (Sweden)

    Srinivas Garlapati

    2011-03-01

    Full Text Available Translation of Giardiavirus (GLV mRNA is initiated at an internal ribosome entry site (IRES in the viral transcript. The IRES localizes to a downstream portion of 5' untranslated region (UTR and a part of the early downstream coding region of the transcript. Recent studies indicated that the IRES does not require a pre-initiation complex to initiate translation but may directly recruit the small ribosome subunit with the help of a number of trans-activating protein factors. A La autoantigen homologue in the viral host Giardia lamblia, GlLa, was proposed as one of the potential trans-activating factors based on its specific binding to GLV-IRES in vitro. In this study, we further elucidated the functional role of GlLa in GLV-IRES mediated translation in Giardia by knocking down GlLa with antisense morpholino oligo, which resulted in a reduction of GLV-IRES activity by 40%. An over-expression of GlLa in Giardia moderately stimulated GLV-IRES activity by 20%. A yeast inhibitory RNA (IRNA, known to bind mammalian and yeast La autoantigen and inhibit Poliovirus and Hepatitis C virus IRES activities in vitro and in vivo, was also found to bind to GlLa protein in vitro and inhibited GLV-IRES function in vivo. The C-terminal domain of La autoantigen interferes with the dimerization of La and inhibits its function. An over-expression of the C-terminal domain (200-348aa of GlLa in Giardia showed a dominant-negative effect on GLV-IRES activity, suggesting a potential inhibition of GlLa dimerization. HA tagged GlLa protein was detected mainly in the cytoplasm of Giardia, thus supporting a primary role of GlLa in translation initiation in Giardiavirus.

  2. Enhancement of the Electrocatalytic Activity of Gold Nanoparticles via Anodic Treatment and the Decrease of the Enhanced Activity with Aging

    International Nuclear Information System (INIS)

    Jo, Kyung Min; Kang, Hyun Ju; Yang, Hae Sik

    2011-01-01

    We have recently shown that the electrocatalytic activity of Au nanoparticles (AuNPs) can be enhanced via NaBH 4 treatment and cathodic treatment and that the enhanced activity slowly decreases with aging. We have also demonstrated that the electrocatalytic activity of the AuNPs freshly prepared by electrochemical or chemical reduction slowly decreases with aging in both air and solution. Likewise, the electrocatalytic activity of anodically treated Au electrodes or AuNPs might change with aging. Herein, we report that the electrocatalytic activity of long-aged AuNPs can be enhanced via anodic treatment and that the enhanced electrocatalytic activity decreases with aging in air. The change in the electrocatalytic activity of AuNPs was evaluated by comparing cyclic voltammograms for the electrooxi-dation of hydrogen peroxide (H 2 O 2 ) and formic acid

  3. A Sequence-Independent, Unstructured Internal Ribosome Entry Site Is Responsible for Internal Expression of the Coat Protein of Turnip Crinkle Virus.

    Science.gov (United States)

    May, Jared; Johnson, Philip; Saleem, Huma; Simon, Anne E

    2017-04-15

    To maximize the coding potential of viral genomes, internal ribosome entry sites (IRES) can be used to bypass the traditional requirement of a 5' cap and some/all of the associated translation initiation factors. Although viral IRES typically contain higher-order RNA structure, an unstructured sequence of about 84 nucleotides (nt) immediately upstream of the Turnip crinkle virus (TCV) coat protein (CP) open reading frame (ORF) has been found to promote internal expression of the CP from the genomic RNA (gRNA) both in vitro and in vivo An absence of extensive RNA structure was predicted using RNA folding algorithms and confirmed by selective 2'-hydroxyl acylation analyzed by primer extension (SHAPE) RNA structure probing. Analysis of the IRES region in vitro by use of both the TCV gRNA and reporter constructs did not reveal any sequence-specific elements but rather suggested that an overall lack of structure was an important feature for IRES activity. The CP IRES is A-rich, independent of orientation, and strongly conserved among viruses in the same genus. The IRES was dependent on eIF4G, but not eIF4E, for activity. Low levels of CP accumulated in vivo in the absence of detectable TCV subgenomic RNAs, strongly suggesting that the IRES was active in the gRNA in vivo Since the TCV CP also serves as the viral silencing suppressor, early translation of the CP from the viral gRNA is likely important for countering host defenses. Cellular mRNA IRES also lack extensive RNA structures or sequence conservation, suggesting that this viral IRES and cellular IRES may have similar strategies for internal translation initiation. IMPORTANCE Cap-independent translation is a common strategy among positive-sense, single-stranded RNA viruses for bypassing the host cell requirement of a 5' cap structure. Viral IRES, in general, contain extensive secondary structure that is critical for activity. In contrast, we demonstrate that a region of viral RNA devoid of extensive secondary

  4. Generation of Pax6-IRES-EGFP knock-in mouse via the cloning-free CRISPR/Cas9 system to reliably visualize neurodevelopmental dynamics.

    Science.gov (United States)

    Inoue, Yukiko U; Morimoto, Yuki; Hoshino, Mikio; Inoue, Takayoshi

    2018-07-01

    Pax6 encodes a transcription factor that plays pivotal roles in eye development, early brain patterning, neocortical arealization, and so forth. Visualization of Pax6 expression dynamics in these events could offer numerous advantages to neurodevelopmental studies. While CRISPR/Cas9 system has dramatically accelerated one-step generation of knock-out mouse, establishment of gene-cassette knock-in mouse via zygote injection has been considered insufficient due to its low efficiency. Recently, an improved CRISPR/Cas9 system for effective gene-cassette knock-in has been reported, where the native form of guide RNAs (crRNA and tracrRNA) assembled with recombinant Cas9 protein are directly delivered into mouse fertilized eggs. Here we apply this strategy to insert IRES-EGFP-pA cassette into Pax6 locus and achieve efficient targeted insertions of the 1.8 kb reporter gene. In Pax6-IRES-EGFP mouse we have generated, EGFP-positive cells reside in the eyes and cerebellum as endogenous Pax6 expressing cells at postnatal day 2. At the early embryonic stages when the embryos are transparent, EGFP-positive regions can be easily identified without PCR-based genotyping, precisely recapitulating the endogenous Pax6 expression patterns. Remarkably, at E12.5, the graded expression patterns of Pax6 in the developing neocortex now become recognizable in our knock-in mice, serving a sufficiently sensitive and useful tool to precisely visualize neurodevelopmental processes. Copyright © 2018 Elsevier B.V. and Japan Neuroscience Society. All rights reserved.

  5. Dynamic gadolinium-enhanced magnetic resonance imaging allows accurate assessment of the synovial inflammatory activity in rheumatoid arthritis knee joints: a comparison with synovial histology

    DEFF Research Database (Denmark)

    Axelsen, Mette Bjørndal; Stoltenberg, M.; Poggenborg, R.

    2012-01-01

    , the average grade of histological synovial inflammation was determined from four biopsies obtained during surgery. A preoperative series of T(1)-weighted dynamic fast low-angle shot (FLASH) MR images was obtained. Parameters characterizing contrast uptake dynamics, including the initial rate of enhancement...... capsule of the knee joint (Precise ROI). Intra- and interreader agreement was assessed using the intra-class correlation coefficient (ICC). Results: The IRE from the Quick ROI and the Precise ROI revealed high correlations to the grade of histological inflammation (Spearman's correlation coefficient (rho......) = 0.70, p = 0.001 and rho = 0.74, p = 0.001, respectively). Intraand inter-reader ICCs were very high (0.93-1.00). No Whole slice parameters were correlated to histology. Conclusion: DCE-MRI provides fast and accurate assessment of synovial inflammation in RA patients. Manual outlining of the joint...

  6. Prodigiosin activates endoplasmic reticulum stress cell death pathway in human breast carcinoma cell lines

    International Nuclear Information System (INIS)

    Pan, Mu-Yun; Shen, Yuh-Chiang; Lu, Chien-Hsing; Yang, Shu-Yi; Ho, Tsing-Fen; Peng, Yu-Ta; Chang, Chia-Che

    2012-01-01

    Prodigiosin is a bacterial tripyrrole pigment with potent cytotoxicity against diverse human cancer cell lines. Endoplasmic reticulum (ER) stress is initiated by accumulation of unfolded or misfolded proteins in the ER lumen and may induce cell death when irremediable. In this study, the role of ER stress in prodigiosin-induced cytotoxicity was elucidated for the first time. Comparable to the ER stress inducer thapsigargin, prodigiosin up-regulated signature ER stress markers GRP78 and CHOP in addition to activating the IRE1, PERK and ATF6 branches of the unfolded protein response (UPR) in multiple human breast carcinoma cell lines, confirming prodigiosin as an ER stress inducer. Prodigiosin transcriptionally up-regulated CHOP, as evidenced by its promoting effect on the CHOP promoter activity. Of note, knockdown of CHOP effectively lowered prodigiosin's capacity to evoke PARP cleavage, reduce cell viability and suppress colony formation, highlighting an essential role of CHOP in prodigiosin-induced cytotoxic ER stress response. In addition, prodigiosin down-regulated BCL2 in a CHOP-dependent manner. Importantly, restoration of BCL2 expression blocked prodigiosin-induced PARP cleavage and greatly enhanced the survival of prodigiosin-treated cells, suggesting that CHOP-dependent BCL2 suppression mediates prodigiosin-elicited cell death. Moreover, pharmacological inhibition of JNK by SP600125 or dominant-negative blockade of PERK-mediated eIF2α phosphorylation impaired prodigiosin-induced CHOP up-regulation and PARP cleavage. Collectively, these results identified ER stress-mediated cell death as a mode-of-action of prodigiosin's tumoricidal effect. Mechanistically, prodigiosin engages the IRE1–JNK and PERK–eIF2α branches of the UPR signaling to up-regulate CHOP, which in turn mediates BCL2 suppression to induce cell death. Highlights: ► Prodigiosin is a bacterial tripyrrole pigment with potent anticancer effect. ► Prodigiosin is herein identified as an

  7. Prodigiosin activates endoplasmic reticulum stress cell death pathway in human breast carcinoma cell lines

    Energy Technology Data Exchange (ETDEWEB)

    Pan, Mu-Yun [Institute of Biomedical Sciences, National Chung Hsing University, Taichung, Taiwan (China); Shen, Yuh-Chiang [Institute of Biomedical Sciences, National Chung Hsing University, Taichung, Taiwan (China); National Research Institute of Chinese Medicine, Taipei, Taiwan (China); Lu, Chien-Hsing [Department of Obstetrics and Gynecology, Taichung Veterans General Hospital, Taichung, Taiwan (China); Department of Obstetrics and Gynecology, National Yang-Ming University School of Medicine, Taipei, Taiwan (China); Yang, Shu-Yi [Institute of Biomedical Sciences, National Chung Hsing University, Taichung, Taiwan (China); Ho, Tsing-Fen [Department of Medical Laboratory Science and Biotechnology, Central Taiwan University of Science and Technology, Taichung, Taiwan (China); Peng, Yu-Ta [Institute of Biomedical Sciences, National Chung Hsing University, Taichung, Taiwan (China); Chang, Chia-Che, E-mail: chia_che@dragon.nchu.edu.tw [Institute of Biomedical Sciences, National Chung Hsing University, Taichung, Taiwan (China); Agricultural Biotechnology Center, National Chung Hsing University, Taichung, Taiwan (China); Graduate Institute of Basic Medical Science, China Medical University, Taichung, Taiwan (China)

    2012-12-15

    Prodigiosin is a bacterial tripyrrole pigment with potent cytotoxicity against diverse human cancer cell lines. Endoplasmic reticulum (ER) stress is initiated by accumulation of unfolded or misfolded proteins in the ER lumen and may induce cell death when irremediable. In this study, the role of ER stress in prodigiosin-induced cytotoxicity was elucidated for the first time. Comparable to the ER stress inducer thapsigargin, prodigiosin up-regulated signature ER stress markers GRP78 and CHOP in addition to activating the IRE1, PERK and ATF6 branches of the unfolded protein response (UPR) in multiple human breast carcinoma cell lines, confirming prodigiosin as an ER stress inducer. Prodigiosin transcriptionally up-regulated CHOP, as evidenced by its promoting effect on the CHOP promoter activity. Of note, knockdown of CHOP effectively lowered prodigiosin's capacity to evoke PARP cleavage, reduce cell viability and suppress colony formation, highlighting an essential role of CHOP in prodigiosin-induced cytotoxic ER stress response. In addition, prodigiosin down-regulated BCL2 in a CHOP-dependent manner. Importantly, restoration of BCL2 expression blocked prodigiosin-induced PARP cleavage and greatly enhanced the survival of prodigiosin-treated cells, suggesting that CHOP-dependent BCL2 suppression mediates prodigiosin-elicited cell death. Moreover, pharmacological inhibition of JNK by SP600125 or dominant-negative blockade of PERK-mediated eIF2α phosphorylation impaired prodigiosin-induced CHOP up-regulation and PARP cleavage. Collectively, these results identified ER stress-mediated cell death as a mode-of-action of prodigiosin's tumoricidal effect. Mechanistically, prodigiosin engages the IRE1–JNK and PERK–eIF2α branches of the UPR signaling to up-regulate CHOP, which in turn mediates BCL2 suppression to induce cell death. Highlights: ► Prodigiosin is a bacterial tripyrrole pigment with potent anticancer effect. ► Prodigiosin is herein identified

  8. Convergence of PASTA kinase and two-component signaling in response to cell wall stress in Enterococcus faecalis.

    Science.gov (United States)

    Kellogg, Stephanie L; Kristich, Christopher J

    2018-04-09

    Two common signal transduction mechanisms used by bacteria to sense and respond to changing environments are two-component systems (TCSs) and eukaryotic-like Ser/Thr kinases and phosphatases (eSTK/Ps). Enterococcus faecalis is a Gram-positive bacterium and serious opportunistic pathogen that relies on both a TCS and an eSTK/P pathway for intrinsic resistance to cell wall-targeting antibiotics. The TCS consists of a histidine kinase (CroS) and response regulator (CroR) that become activated upon exposure of cells to cell wall-targeting antibiotics, leading to modulation of gene expression. The eSTK/P pathway consists of a transmembrane kinase (IreK) and its cognate phosphatase (IreP), which act antagonistically to mediate antibiotic resistance through an unknown mechanism. Because both CroS/R and IreK/P contribute to enterococcal resistance towards cell wall-targeting antibiotics, we hypothesized these signaling systems are intertwined. To test this hypothesis, we analyzed CroR phosphorylation and CroS/R-dependent gene expression to probe the influence of IreK and IreP on CroS/R signaling. In addition, we analyzed the phosphorylation state of CroS which revealed IreK-dependent phosphorylation of a Thr residue important for CroS function. Our results are consistent with a model in which IreK positively influences CroR-dependent gene expression through phosphorylation of CroS to promote antimicrobial resistance in E. faecalis Importance Two-component signaling systems (TCSs) and eukaryotic-like Ser/Thr kinases (eSTKs) are used by bacteria to sense and adapt to changing environments. Understanding how these pathways are regulated to promote bacterial survival is critical for a more complete understanding of bacterial stress responses and physiology. The opportunistic pathogen Enterococcus faecalis relies on both a TCS (CroS/R) and an eSTK (IreK) for intrinsic resistance to cell wall-targeting antibiotics. We probed the relationship between CroS/R and IreK, revealing

  9. Method for enhancing amidohydrolase activity of fatty acid amide hydrolase

    Science.gov (United States)

    John, George; Nagarajan, Subbiah; Chapman, Kent; Faure, Lionel; Koulen, Peter

    2016-10-25

    A method for enhancing amidohydrolase activity of Fatty Acid Amide Hydrolase (FAAH) is disclosed. The method comprising administering a phenoxyacylethanolamide that causes the enhanced activity. The enhanced activity can have numerous effects on biological organisms including, for example, enhancing the growth of certain seedlings. The subject matter disclosed herein relates to enhancers of amidohydrolase activity.

  10. Undergraduate Student Involvement in International Research - The IRES Program at MAX-lab, Sweden

    Science.gov (United States)

    Briscoe, William; O'Rielly, Grant; Fissum, Kevin

    2014-03-01

    Undergraduate students associated with The George Washington University and UMass Dartmouth have had the opportunity to participate in nuclear physics research as a part of the PIONS@MAXLAB Collaboration performing experiments at MAX-lab at Lund University in Sweden. This project has supported thirteen undergraduate students during 2009 - 2011. The student researchers are involved with all aspects of the experiments performed at the laboratory, from set-up to analysis and presentation at national conferences. These experiments investigate the dynamics responsible for the internal structure of the nucleon through the study of pion photoproduction off the nucleon and high-energy Compton scattering. Along with the US and Swedish project leaders, members of the collaboration (from four different countries) have contributed to the training and mentoring of these students. This program provides students with international research experiences that prepare them to operate successfully in a global environment and encourages them to stay in areas of science, technology, engineering and math (STEM) that are crucial for our modern, technology-dependent society. We will present the history, goals and outcomes in both physics results and student success that have come from this program. This work supported by NSF OISE/IRES award 0553467.

  11. Activation of the cellular unfolded protein response by recombinant adeno-associated virus vectors.

    Directory of Open Access Journals (Sweden)

    Balaji Balakrishnan

    Full Text Available The unfolded protein response (UPR is a stress-induced cyto-protective mechanism elicited towards an influx of large amount of proteins in the endoplasmic reticulum (ER. In the present study, we evaluated if AAV manipulates the UPR pathways during its infection. We first examined the role of the three major UPR axes, namely, endoribonuclease inositol-requiring enzyme-1 (IRE1α, activating transcription factor 6 (ATF6 and PKR-like ER kinase (PERK in AAV infected cells. Total RNA from mock or AAV infected HeLa cells were used to determine the levels of 8 different ER-stress responsive transcripts from these pathways. We observed a significant up-regulation of IRE1α (up to 11 fold and PERK (up to 8 fold genes 12-48 hours after infection with self-complementary (scAAV2 but less prominent with single-stranded (ssAAV2 vectors. Further studies demonstrated that scAAV1 and scAAV6 also induce cellular UPR in vitro, with AAV1 vectors activating the PERK pathway (3 fold while AAV6 vectors induced a significant increase on all the three major UPR pathways [6-16 fold]. These data suggest that the type and strength of UPR activation is dependent on the viral capsid. We then examined if transient inhibition of UPR pathways by RNA interference has an effect on AAV transduction. siRNA mediated silencing of PERK and IRE1α had a modest effect on AAV2 and AAV6 mediated gene expression (∼1.5-2 fold in vitro. Furthermore, hepatic gene transfer of scAAV2 vectors in vivo, strongly elevated IRE1α and PERK pathways (2 and 3.5 fold, respectively. However, when animals were pre-treated with a pharmacological UPR inhibitor (metformin during scAAV2 gene transfer, the UPR signalling and its subsequent inflammatory response was attenuated concomitant to a modest 2.8 fold increase in transgene expression. Collectively, these data suggest that AAV vectors activate the cellular UPR pathways and their selective inhibition may be beneficial during AAV mediated gene transfer.

  12. Molecular cloning and preliminary function study of iron responsive element binding protein 1 gene from cypermethrin-resistant Culex pipiens pallens

    Directory of Open Access Journals (Sweden)

    Tan Wenbin

    2011-11-01

    Full Text Available Abstract Background Insecticide resistance jeopardizes the control of mosquito populations and mosquito-borne disease control, which creates a major public health concern. Two-dimensional electrophoresis identified one protein segment with high sequence homology to part of Aedes aegypti iron-responsive element binding protein (IRE-BP. Method RT-PCR and RACE (rapid amplification of cDNA end were used to clone a cDNA encoding full length IRE-BP 1. Real-time quantitative RT-PCR was used to evaluate the transcriptional level changes in the Cr-IRE strain Aedes aegypti compared to the susceptible strain of Cx. pipiens pallens. The expression profile of the gene was established in the mosquito life cycle. Methyl tritiated thymidine (3H-TdR was used to observe the cypermethrin resistance changes in C6/36 cells containing the stably transfected IRE-BP 1 gene of Cx. pipiens pallens. Results The complete sequence of iron responsive element binding protein 1 (IRE-BP 1 has been cloned from the cypermethrin-resistant strain of Culex pipiens pallens (Cr-IRE strain. Quantitative RT-PCR analysis indicated that the IRE-BP 1 transcription level was 6.7 times higher in the Cr-IRE strain than in the susceptible strain of 4th instar larvae. The IRE-BP 1 expression was also found to be consistently higher throughout the life cycle of the Cr-IRE strain. A protein of predicted size 109.4 kDa has been detected by Western blotting in IRE-BP 1-transfected mosquito C6/36 cells. These IRE-BP 1-transfected cells also showed enhanced cypermethrin resistance compared to null-transfected or plasmid vector-transfected cells as determined by 3H-TdR incorporation. Conclusion IRE-BP 1 is expressed at higher levels in the Cr-IRE strain, and may confer some insecticide resistance in Cx. pipiens pallens.

  13. Irreversible electroporation ablation area enhanced by synergistic high- and low-voltage pulses.

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    Chenguo Yao

    Full Text Available Irreversible electroporation (IRE produced by a pulsed electric field can ablate tissue. In this study, we achieved an enhancement in ablation area by using a combination of short high-voltage pulses (HVPs to create a large electroporated area and long low-voltage pulses (LVPs to ablate the electroporated area. The experiments were conducted in potato tuber slices. Slices were ablated with an array of four pairs of parallel steel electrodes using one of the following four electric pulse protocols: HVP, LVP, synergistic HVP+LVP (SHLVP or LVP+HVP. Our results showed that the SHLVPs more effectively necrotized tissue than either the HVPs or LVPs, even when the SHLVP dose was the same as or lower than the HVP or LVP doses. The HVP and LVP order mattered and only HVPs+LVPs (SHLVPs treatments increased the size of the ablation zone because the HVPs created a large electroporated area that was more susceptible to the subsequent LVPs. Real-time temperature change monitoring confirmed that the tissue was non-thermally ablated by the electric pulses. Theoretical calculations of the synergistic effects of the SHLVPs on tissue ablation were performed. Our proposed SHLVP protocol provides options for tissue ablation and may be applied to optimize the current clinical IRE protocols.

  14. Irreversible electroporation ablation area enhanced by synergistic high- and low-voltage pulses.

    Science.gov (United States)

    Yao, Chenguo; Lv, Yanpeng; Dong, Shoulong; Zhao, Yajun; Liu, Hongmei

    2017-01-01

    Irreversible electroporation (IRE) produced by a pulsed electric field can ablate tissue. In this study, we achieved an enhancement in ablation area by using a combination of short high-voltage pulses (HVPs) to create a large electroporated area and long low-voltage pulses (LVPs) to ablate the electroporated area. The experiments were conducted in potato tuber slices. Slices were ablated with an array of four pairs of parallel steel electrodes using one of the following four electric pulse protocols: HVP, LVP, synergistic HVP+LVP (SHLVP) or LVP+HVP. Our results showed that the SHLVPs more effectively necrotized tissue than either the HVPs or LVPs, even when the SHLVP dose was the same as or lower than the HVP or LVP doses. The HVP and LVP order mattered and only HVPs+LVPs (SHLVPs) treatments increased the size of the ablation zone because the HVPs created a large electroporated area that was more susceptible to the subsequent LVPs. Real-time temperature change monitoring confirmed that the tissue was non-thermally ablated by the electric pulses. Theoretical calculations of the synergistic effects of the SHLVPs on tissue ablation were performed. Our proposed SHLVP protocol provides options for tissue ablation and may be applied to optimize the current clinical IRE protocols.

  15. HuR and Ago2 Bind the Internal Ribosome Entry Site of Enterovirus 71 and Promote Virus Translation and Replication.

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    Jing-Yi Lin

    Full Text Available EV71 (enterovirus 71 RNA contains an internal ribosomal entry site (IRES that directs cap-independent initiation of translation. IRES-dependent translation requires the host's translation initiation factors and IRES-associated trans-acting factors (ITAFs. We reported recently that mRNA decay factor AUF1 is a negative-acting ITAF that binds IRES stem-loop II. We also reported that the small RNA-processing enzyme Dicer produces at least four small RNAs (vsRNAs from the EV71 IRES. One of these, vsRNA1, derived from IRES stem-loop II, reduces IRES activity and virus replication. Since its mechanism of action is unknown, we hypothesized that it might control association of ITAFs with the IRES. Here, we identified the mRNA stability factor HuR and the RISC subunit Argonaute 2 (Ago2 as two ITAFs that bind stem-loop II. In contrast to AUF1, HuR and Ago2 promote EV71 IRES activity and virus replication. In vitro RNA-binding assays revealed that vsRNA1 can alter association of Ago2, HuR, and AUF1 with stem-loop II. This presents a possible mechanism by which vsRNA1 could control viral translation and replication.

  16. Oblongifolin M, an active compound isolated from a Chinese medical herb Garcinia oblongifolia, potently inhibits enterovirus 71 reproduction through downregulation of ERp57.

    Science.gov (United States)

    Wang, Mengjie; Dong, Qi; Wang, Hua; He, Yaqing; Chen, Ying; Zhang, Hong; Wu, Rong; Chen, Xinchun; Zhou, Boping; He, Jason; Kung, Hsiang-Fu; Huang, Canhua; Wei, Yuquan; Huang, Jian-dong; Xu, Hongxi; He, Ming-Liang

    2016-02-23

    There is no effective drug to treat EV71 infection yet. Traditional Chinese herbs are great resources for novel antiviral compounds. Here we showed that Oblongifolin M (OM), an active compound isolated from Garcinia oblongifolia, potently inhibited EV71 infection in a dose dependent manner. To identify its potential effectors in the host cells, we successfully identified 18 proteins from 52 differentially expressed spots by comparative proteomics studies. Further studies showed that knockdown of ERp57 inhibited viral replication through downregulating viral IRES (internal ribosome entry site) activities, whereas ectopic expression of ERp57 increased IRES activity and partly rescued the inhibitory effects of OM on viral replication. We demonstrated that OM is an effective antiviral agent; and that ERp57 is one of its cellular effectors against EV71 infection.

  17. Method for enhancing amidohydrolase activity of fatty acid amide hydrolase

    Science.gov (United States)

    John, George; Nagarajan, Subbiah; Chapman, Kent; Faure, Lionel; Koulen, Peter

    2017-12-26

    A method for enhancing amidohydrolase activity of Fatty Acid Amide Hydrolase (FAAH) is disclosed. The method comprising administering a phenoxyacyl-ethanolamide that causes the enhanced activity. The enhanced activity can have numerous effects on biological organisms including, for example, enhancing the growth of certain seedlings.

  18. Enhanced activation of the left hemisphere promotes normative decision making.

    Science.gov (United States)

    Corser, Ryan; Jasper, John D

    2014-01-01

    Previous studies have reported that enhanced activation of the left cerebral hemisphere reduces risky-choice, attribute, and goal-framing effects relative to enhanced activation of the right cerebral hemisphere. The present study sought to extend these findings and show that enhanced activation of the left hemisphere also reduces violations of other normative principles, besides the invariance principle. Participants completed ratio bias (Experiment 1, N = 296) and base rate neglect problems (Experiment 2, N = 145) under normal (control) viewing or with the right or left hemisphere primarily activated by imposing a unidirectional gaze. In Experiment 1 we found that enhanced left hemispheric activation reduced the ratio bias relative to normal viewing and a group experiencing enhanced right hemispheric activation. In Experiment 2 enhanced left hemispheric activation resulted in using base rates more than normal viewing, but not significantly more than enhanced right hemispheric activation. Results suggest that hemispheric asymmetries can affect higher-order cognitive processes, such as decision-making biases. Possible theoretical accounts are discussed as well as implications for dual-process theories.

  19. Modeling cancer registration processes with an enhanced activity diagram.

    Science.gov (United States)

    Lyalin, D; Williams, W

    2005-01-01

    Adequate instruments are needed to reflect the complexity of routine cancer registry operations properly in a business model. The activity diagram is a key instrument of the Unified Modeling Language (UML) for the modeling of business processes. The authors aim to improve descriptions of processes in cancer registration, as well as in other public health domains, through the enhancements of an activity diagram notation within the standard semantics of UML. The authors introduced the practical approach to enhance a conventional UML activity diagram, complementing it with the following business process concepts: timeline, duration for individual activities, responsibilities for individual activities within swimlanes, and descriptive text. The authors used an enhanced activity diagram for modeling surveillance processes in the cancer registration domain. Specific example illustrates the use of an enhanced activity diagram to visualize a process of linking cancer registry records with external mortality files. Enhanced activity diagram allows for the addition of more business concepts to a single diagram and can improve descriptions of processes in cancer registration, as well as in other domains. Additional features of an enhanced activity diagram allow to advance the visualization of cancer registration processes. That, in turn, promotes the clarification of issues related to the process timeline, responsibilities for particular operations, and collaborations among process participants. Our first experiences in a cancer registry best practices development workshop setting support the usefulness of such an approach.

  20. Apigenin Restricts FMDV Infection and Inhibits Viral IRES Driven Translational Activity

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    Suhong Qian

    2015-03-01

    Full Text Available Foot-and-mouth disease (FMD is a highly contagious disease of domestic and wild ruminants that is caused by FMD virus (FMDV. FMD outbreaks have occurred in livestock-containing regions worldwide. Apigenin, which is a flavonoid naturally existing in plant, possesses various pharmacological effects, including anti-inflammatory, anticancer, antioxidant and antiviral activities. Results show that apigenin can inhibit FMDV-mediated cytopathogenic effect and FMDV replication in vitro. Further studies demonstrate the following: (i apigenin inhibits FMDV infection at the viral post-entry stage; (ii apigenin does not exhibit direct extracellular virucidal activity; and (iii apigenin interferes with the translational activity of FMDV driven by internal ribosome entry site. Studies on applying apigein in vivo are required for drug development and further identification of potential drug targets against FDMV infection.

  1. Apigenin restricts FMDV infection and inhibits viral IRES driven translational activity.

    Science.gov (United States)

    Qian, Suhong; Fan, Wenchun; Qian, Ping; Zhang, Dong; Wei, Yurong; Chen, Huanchun; Li, Xiangmin

    2015-03-31

    Foot-and-mouth disease (FMD) is a highly contagious disease of domestic and wild ruminants that is caused by FMD virus (FMDV). FMD outbreaks have occurred in livestock-containing regions worldwide. Apigenin, which is a flavonoid naturally existing in plant, possesses various pharmacological effects, including anti-inflammatory, anticancer, antioxidant and antiviral activities. Results show that apigenin can inhibit FMDV-mediated cytopathogenic effect and FMDV replication in vitro. Further studies demonstrate the following: (i) apigenin inhibits FMDV infection at the viral post-entry stage; (ii) apigenin does not exhibit direct extracellular virucidal activity; and (iii) apigenin interferes with the translational activity of FMDV driven by internal ribosome entry site. Studies on applying apigein in vivo are required for drug development and further identification of potential drug targets against FDMV infection.

  2. Percutaneous Irreversible Electroporation Lung Ablation: Preliminary Results in a Porcine Model

    International Nuclear Information System (INIS)

    Deodhar, Ajita; Monette, Sébastien; Single, Gordon W.; Hamilton, William C.; Thornton, Raymond H.; Sofocleous, Constantinos T.; Maybody, Majid; Solomon, Stephen B.

    2011-01-01

    Objective: Irreversible electroporation (IRE) uses direct electrical pulses to create permanent “pores” in cell membranes to cause cell death. In contrast to conventional modalities, IRE has a nonthermal mechanism of action. Our objective was to study the histopathological and imaging features of IRE in normal swine lung. Materials and Methods: Eleven female swine were studied for hyperacute (8 h), acute (24 h), subacute (96 h), and chronic (3 week) effects of IRE ablation in lung. Paired unipolar IRE applicators were placed under computed tomography (CT) guidance. Some applicators were deliberately positioned near bronchovascular structures. IRE pulse delivery was synchronized with the cardiac rhythm only when ablation was performed within 2 cm of the heart. Contrast-enhanced CT scan was performed immediately before and after IRE and at 1 and 3 weeks after IRE ablation. Representative tissue was stained with hematoxylin and eosin for histopathology. Results: Twenty-five ablations were created: ten hyperacute, four acute, and three subacute ablations showed alveolar edema and necrosis with necrosis of bronchial, bronchiolar, and vascular epithelium. Bronchovascular architecture was maintained. Chronic ablations showed bronchiolitis obliterans and alveolar interstitial fibrosis. Immediate post-procedure CT images showed linear or patchy density along the applicator tract. At 1 week, there was consolidation that resolved partially or completely by 3 weeks. Pneumothorax requiring chest tube developed in two animals; no significant cardiac arrhythmias were noted. Conclusion: Our preliminary porcine study demonstrates the nonthermal and extracellular matrix sparing mechanism of action of IRE. IRE is a potential alternative to thermal ablative modalities.

  3. Internal ribosomal entry site-mediated translation is important for rhythmic PERIOD1 expression.

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    Kyung-Ha Lee

    Full Text Available The mouse PERIOD1 (mPER1 plays an important role in the maintenance of circadian rhythm. Translation of mPer1 is directed by both a cap-dependent process and cap-independent translation mediated by an internal ribosomal entry site (IRES in the 5' untranslated region (UTR. Here, we compared mPer1 IRES activity with other cellular IRESs. We also found critical region in mPer1 5'UTR for heterogeneous nuclear ribonucleoprotein Q (HNRNPQ binding. Deletion of HNRNPQ binding region markedly decreased IRES activity and disrupted rhythmicity. A mathematical model also suggests that rhythmic IRES-dependent translation is a key process in mPER1 oscillation. The IRES-mediated translation of mPer1 will help define the post-transcriptional regulation of the core clock genes.

  4. Discovery of stimulation-responsive immune enhancers with CRISPR activation

    Science.gov (United States)

    Simeonov, Dimitre R.; Gowen, Benjamin G.; Boontanrart, Mandy; Roth, Theodore L.; Gagnon, John D.; Mumbach, Maxwell R.; Satpathy, Ansuman T.; Lee, Youjin; Bray, Nicolas L.; Chan, Alice Y.; Lituiev, Dmytro S.; Nguyen, Michelle L.; Gate, Rachel E.; Subramaniam, Meena; Li, Zhongmei; Woo, Jonathan M.; Mitros, Therese; Ray, Graham J.; Curie, Gemma L.; Naddaf, Nicki; Chu, Julia S.; Ma, Hong; Boyer, Eric; van Gool, Frederic; Huang, Hailiang; Liu, Ruize; Tobin, Victoria R.; Schumann, Kathrin; Daly, Mark J.; Farh, Kyle K.; Ansel, K. Mark; Ye, Chun J.; Greenleaf, William J.; Anderson, Mark S.; Bluestone, Jeffrey A.; Chang, Howard Y.; Corn, Jacob E.; Marson, Alexander

    2017-09-01

    The majority of genetic variants associated with common human diseases map to enhancers, non-coding elements that shape cell-type-specific transcriptional programs and responses to extracellular cues. Systematic mapping of functional enhancers and their biological contexts is required to understand the mechanisms by which variation in non-coding genetic sequences contributes to disease. Functional enhancers can be mapped by genomic sequence disruption, but this approach is limited to the subset of enhancers that are necessary in the particular cellular context being studied. We hypothesized that recruitment of a strong transcriptional activator to an enhancer would be sufficient to drive target gene expression, even if that enhancer was not currently active in the assayed cells. Here we describe a discovery platform that can identify stimulus-responsive enhancers for a target gene independent of stimulus exposure. We used tiled CRISPR activation (CRISPRa) to synthetically recruit a transcriptional activator to sites across large genomic regions (more than 100 kilobases) surrounding two key autoimmunity risk loci, CD69 and IL2RA. We identified several CRISPRa-responsive elements with chromatin features of stimulus-responsive enhancers, including an IL2RA enhancer that harbours an autoimmunity risk variant. Using engineered mouse models, we found that sequence perturbation of the disease-associated Il2ra enhancer did not entirely block Il2ra expression, but rather delayed the timing of gene activation in response to specific extracellular signals. Enhancer deletion skewed polarization of naive T cells towards a pro-inflammatory T helper (TH17) cell state and away from a regulatory T cell state. This integrated approach identifies functional enhancers and reveals how non-coding variation associated with human immune dysfunction alters context-specific gene programs.

  5. Discovery of stimulation-responsive immune enhancers with CRISPR activation

    Science.gov (United States)

    Simeonov, Dimitre R.; Gowen, Benjamin G.; Boontanrart, Mandy; Roth, Theodore L.; Gagnon, John D.; Mumbach, Maxwell R.; Satpathy, Ansuman T.; Lee, Youjin; Bray, Nicolas L.; Chan, Alice Y.; Lituiev, Dmytro S.; Nguyen, Michelle L.; Gate, Rachel E.; Subramaniam, Meena; Li, Zhongmei; Woo, Jonathan M.; Mitros, Therese; Ray, Graham J.; Curie, Gemma L.; Naddaf, Nicki; Chu, Julia S.; Ma, Hong; Boyer, Eric; Van Gool, Frederic; Huang, Hailiang; Liu, Ruize; Tobin, Victoria R.; Schumann, Kathrin; Daly, Mark J.; Farh, Kyle K; Ansel, K. Mark; Ye, Chun J.; Greenleaf, William J.; Anderson, Mark S.; Bluestone, Jeffrey A.; Chang, Howard Y.; Corn, Jacob E.; Marson, Alexander

    2017-01-01

    The majority of genetic variants associated with common human diseases map to enhancers, non-coding elements that shape cell-type-specific transcriptional programs and responses to extracellular cues1–3. Systematic mapping of functional enhancers and their biological contexts is required to understand the mechanisms by which variation in non-coding genetic sequences contributes to disease. Functional enhancers can be mapped by genomic sequence disruption4–6, but this approach is limited to the subset of enhancers that are necessary in the particular cellular context being studied. We hypothesized that recruitment of a strong transcriptional activator to an enhancer would be sufficient to drive target gene expression, even if that enhancer was not currently active in the assayed cells. Here we describe a discovery platform that can identify stimulus-responsive enhancers for a target gene independent of stimulus exposure. We used tiled CRISPR activation (CRISPRa)7 to synthetically recruit a transcriptional activator to sites across large genomic regions (more than 100 kilobases) surrounding two key autoimmunity risk loci, CD69 and IL2RA. We identified several CRISPRa-responsive elements with chromatin features of stimulus-responsive enhancers, including an IL2RA enhancer that harbours an autoimmunity risk variant. Using engineered mouse models, we found that sequence perturbation of the disease-associated Il2ra enhancer did not entirely block Il2ra expression, but rather delayed the timing of gene activation in response to specific extracellular signals. Enhancer deletion skewed polarization of naive T cells towards a pro-inflammatory T helper (TH17) cell state and away from a regulatory T cell state. This integrated approach identifies functional enhancers and reveals how non-coding variation associated with human immune dysfunction alters context-specific gene programs. PMID:28854172

  6. A BCR/ABL-hIL-2 DNA Vaccine Enhances the Immune Responses in BALB/c Mice

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    Yanan Qin

    2013-01-01

    Full Text Available The use of a DNA vaccine encoding the BCR/ABL fusion gene is thought to be a promising approach for patients with chronic myeloid leukemia (CML to eradicate minimal residual disease after treatment with chemotherapy or targeted therapy. In this study, our strategy employs genetic technology to create a DNA vaccine encoding the BCR/ABL fusion and human interleukin-2 (hIL-2 genes. The successfully constructed plasmids BCR/ABL-pIRES-hIL-2, BCR/ABL-pIRES, and pIRES-hIL-2 were delivered intramuscularly to BALB/c mice at 14-day intervals for three cycles. The transcription and expression of the BCR/ABL and hIL-2 genes were found in the injected muscle tissues. The interferon-γ (IFN-γ serum levels were increased, and the splenic CD4+/CD8+ T cell ratio was significantly decreased in the BCR/ABL-pIRES-hIL-2-injected mice. Furthermore, specific antibodies against K562 cells could be detected by indirect immunofluorescence. These results indicate that a DNA vaccine containing BCR/ABL and hIL-2 together may elicit increased in vivo humoral and cellular immune responses in BALB/c mice.

  7. Construction of a recombinant adenovirus co-expressing truncated human prostate-specific membrane antigen and mouse 4-1BBL genes and its effect on dendritic cells

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    Xiaodong Weng

    2011-03-01

    Full Text Available Our aim was to construct a recombinant adenovirus co-expressing truncated human prostate-specific membrane antigen (tPSMA and mouse 4-1BBL genes and to determine its effect on dendritic cells (DCs generated from bone marrow suspensions harvested from C57BL/6 mice for which the effect of 4-1BBL on DCs is not clear, especially during DCs processing tumor-associated antigen. Replication deficient adenovirus AdMaxTM Expression System was used to construct recombinant adenovirus Ad-tPSMA-internal ribosome entry site-mouse 4-1BBL (Ad-tPSMA-IRES-m4-1BBL and Ad-enhanced green fluorescent protein. Day 7 proliferating DC aggregates generated from C57BL/6 mice were collected as immature DCs and further mature DCs were obtained by lipopolysaccharide activated immature DCs. After DCs were exposed to the recombinant adenovirus with 250 multiplicity of infection, the expression of tPSMA and m4-1BBL proteins were detected by Western blot, and the apoptosis and phenotype of DCs were analyzed by flow cytometry. Cytokines (IL-6 and IL-12 in the supernatant were detected by enzyme-linked immunosorbent assay (ELISA. Proliferation of T cells was detected by allogeneic mixed lymphocyte reactions. The tPSMA and m4-1BBL proteins were expressed correctly. The apoptosis rate of DCs transfected with Ad-tPSMA-IRES-m4-1BBL was 14.6%, lower than that of control DCs. The expression of co-stimulatory molecules [CD80 (81.6 ± 5.4% and CD86 (80.13 ± 2.81%] up-regulated in Ad-tPSMA-IRES-m4-1BBL-pulsed DCs, and the level of IL-6 (3960.2 ± 50.54 pg/mL and IL-12 (249.57 ± 12.51 pg/mL production in Ad-tPSMA-IRES-m4-1BBL-transduced DCs were significantly higher (P < 0.05 than those in control DCs. Ad-tPSMA-IRES-m4-1BBL induced higher T-cell proliferation (OD450 = 0.614 ± 0.018, indicating that this recombinant adenovirus can effectively enhance the activity of DCs.

  8. Inflammatory response to strenuous muscular exercise in man

    Directory of Open Access Journals (Sweden)

    G. Camus

    1993-01-01

    Full Text Available Based on the humoral and cellular changes occurring during strenuous muscular work in humans, the concept of inflammatory response to exercise (IRE is developed. The main indices of IRE consist of signs of an acute phase response, leucocytosis and leucocyte activation, release of inflammatory mediators, tissue damage and cellular infiltrates, production of free radicals, activation of complement, and coagulation and fibrinolytic pathways. Depending on exercise intensity and duration, it seems likely that muscle and/or associated connective tissue damage, contact system activation due to shear stress on endothelium and endotoxaemia could be the triggering mechanisms of IRE. Although this phenomenon can be considered in most cases as a physiological process associated with tissue repair, exaggerated IRE could have physiopathological consequences. On the other hand, the influence of several factors such as age, sex, training, hormonal status, nutrition, anti-inflammatory drugs, and the extent to which IRE could be a potential risk for subjects undergoing intense physical training require further study.

  9. Papel da via de sinalização mediada por Ire1 e Xbp1 na diferenciação de fotoreceptores em Drosophila

    OpenAIRE

    Coelho, Dina Raquel da Silva, 1984-

    2009-01-01

    Tese de mestrado. Biologia (Biologia Molecular Humana). Universidade de Lisboa, Faculdade de Ciências, 2009 O mecanismo de Unfolded Protein Response (UPR) protege as células do stress no retículo endoplasmático (RE) causado pela acumulação de proteínas misfolded no seu lúmen. Este mecanismo leva à activação de um conjunto de vias de sinalização que aumenta a capacidade de folding de proteínas no RE. No presente trabalho, analisámos o papel da via do UPR mediada por Ire1 e Xbp1 no desenvolv...

  10. Enhanced NIF neutron activation diagnostics.

    Science.gov (United States)

    Yeamans, C B; Bleuel, D L; Bernstein, L A

    2012-10-01

    The NIF neutron activation diagnostic suite relies on removable activation samples, leading to operational inefficiencies and a fundamental lower limit on the half-life of the activated product that can be observed. A neutron diagnostic system measuring activation of permanently installed samples could remove these limitations and significantly enhance overall neutron diagnostic capabilities. The physics and engineering aspects of two proposed systems are considered: one measuring the (89)Zr/(89 m)Zr isomer ratio in the existing Zr activation medium and the other using potassium zirconate as the activation medium. Both proposed systems could improve the signal-to-noise ratio of the current system by at least a factor of 5 and would allow independent measurement of fusion core velocity and fuel areal density.

  11. Re-localization of Cellular Protein SRp20 during Poliovirus Infection: Bridging a Viral IRES to the Host Cell Translation Apparatus

    Science.gov (United States)

    Fitzgerald, Kerry D.; Semler, Bert L.

    2011-01-01

    Poliovirus IRES-mediated translation requires the functions of certain canonical as well as non-canonical factors for the recruitment of ribosomes to the viral RNA. The interaction of cellular proteins PCBP2 and SRp20 in extracts from poliovirus-infected cells has been previously described, and these two proteins were shown to function synergistically in viral translation. To further define the mechanism of ribosome recruitment for the initiation of poliovirus IRES-dependent translation, we focused on the role of the interaction between cellular proteins PCBP2 and SRp20. Work described here demonstrates that SRp20 dramatically re-localizes from the nucleus to the cytoplasm of poliovirus-infected neuroblastoma cells during the course of infection. Importantly, SRp20 partially co-localizes with PCBP2 in the cytoplasm of infected cells, corroborating our previous in vitro interaction data. In addition, the data presented implicate the presence of these two proteins in viral translation initiation complexes. We show that in extracts from poliovirus-infected cells, SRp20 is associated with PCBP2 bound to poliovirus RNA, indicating that this interaction occurs on the viral RNA. Finally, we generated a mutated version of SRp20 lacking the RNA recognition motif (SRp20ΔRRM) and found that this protein is localized similar to the full length SRp20, and also partially co-localizes with PCBP2 during poliovirus infection. Expression of this mutated version of SRp20 results in a ∼100 fold decrease in virus yield for poliovirus when compared to expression of wild type SRp20, possibly via a dominant negative effect. Taken together, these results are consistent with a model in which SRp20 interacts with PCBP2 bound to the viral RNA, and this interaction functions to recruit ribosomes to the viral RNA in a direct or indirect manner, with the participation of additional protein-protein or protein-RNA interactions. PMID:21779168

  12. Estrogen Receptor β Agonist Attenuates Endoplasmic Reticulum Stress-Induced Changes in Social Behavior and Brain Connectivity in Mice.

    Science.gov (United States)

    Crider, Amanda; Nelson, Tyler; Davis, Talisha; Fagan, Kiley; Vaibhav, Kumar; Luo, Matthew; Kamalasanan, Sunay; Terry, Alvin V; Pillai, Anilkumar

    2018-02-12

    Impaired social interaction is a key feature of several major psychiatric disorders including depression, autism, and schizophrenia. While, anatomically, the prefrontal cortex (PFC) is known as a key regulator of social behavior, little is known about the cellular mechanisms that underlie impairments of social interaction. One etiological mechanism implicated in the pathophysiology of the aforementioned psychiatric disorders is cellular stress and consequent adaptive responses in the endoplasmic reticulum (ER) that can result from a variety of environmental and physical factors. The ER is an organelle that serves essential roles in protein modification, folding, and maturation of proteins; however, the specific role of ER stress in altered social behavior is unknown. In this study, treatment with tunicamycin, an ER stress inducer, enhanced the phosphorylation level of inositol-requiring ER-to-nucleus signal kinase 1 (IRE1) and increased X-box-binding protein 1 (XBP1) mRNA splicing activity in the mouse PFC, whereas inhibition of IRE1/XBP1 pathway in PFC by a viral particle approach attenuated social behavioral deficits caused by tunicamycin treatment. Reduced estrogen receptor beta (ERβ) protein levels were found in the PFC of male mice following tunicamycin treatment. Pretreatment with an ERβ specific agonist, ERB-041 significantly attenuated tunicamycin-induced deficits in social behavior, and activation of IRE1/XBP1 pathway in mouse PFC. Moreover, ERB-041 inhibited tunicamycin-induced increases in functional connectivity between PFC and hippocampus in male mice. Together, these results show that ERβ agonist attenuates ER stress-induced deficits in social behavior through the IRE-1/XBP1 pathway.

  13. Antiviral activity of a small molecule deubiquitinase inhibitor occurs via induction of the unfolded protein response.

    Directory of Open Access Journals (Sweden)

    Jeffrey W Perry

    Full Text Available Ubiquitin (Ub is a vital regulatory component in various cellular processes, including cellular responses to viral infection. As obligate intracellular pathogens, viruses have the capacity to manipulate the ubiquitin (Ub cycle to their advantage by encoding Ub-modifying proteins including deubiquitinases (DUBs. However, how cellular DUBs modulate specific viral infections, such as norovirus, is poorly understood. To examine the role of DUBs during norovirus infection, we used WP1130, a small molecule inhibitor of a subset of cellular DUBs. Replication of murine norovirus in murine macrophages and the human norovirus Norwalk virus in a replicon system were significantly inhibited by WP1130. Chemical proteomics identified the cellular DUB USP14 as a target of WP1130 in murine macrophages, and pharmacologic inhibition or siRNA-mediated knockdown of USP14 inhibited murine norovirus infection. USP14 is a proteasome-associated DUB that also binds to inositol-requiring enzyme 1 (IRE1, a critical mediator of the unfolded protein response (UPR. WP1130 treatment of murine macrophages did not alter proteasome activity but activated the X-box binding protein-1 (XBP-1 through an IRE1-dependent mechanism. In addition, WP1130 treatment or induction of the UPR also reduced infection of other RNA viruses including encephalomyocarditis virus, Sindbis virus, and La Crosse virus but not vesicular stomatitis virus. Pharmacologic inhibition of the IRE1 endonuclease activity partially rescued the antiviral effect of WP1130. Taken together, our studies support a model whereby induction of the UPR through cellular DUB inhibition blocks specific viral infections, and suggest that cellular DUBs and the UPR represent novel targets for future development of broad spectrum antiviral therapies.

  14. Curcumin attenuates glutamate neurotoxicity in the hippocampus by suppression of ER stress-associated TXNIP/NLRP3 inflammasome activation in a manner dependent on AMPK

    Energy Technology Data Exchange (ETDEWEB)

    Li, Ying; Li, Jia; Li, Shanshan; Li, Yi; Wang, Xiangxiang; Liu, Baolin [Department of Pharmacology of Chinese Materia Medica, China Pharmaceutical University, Nanjing, 639, Longmian Road, Nanjing 211198 (China); Jiangsu Provincial Key Laboratory for TCM Evaluation and Translational Research, China Pharmaceutical University, 639, Longmian Road, Nanjing 211198 (China); Fu, Qiang, E-mail: fuqiang@cpu.edu.cn [Department of Pharmacology of Chinese Materia Medica, China Pharmaceutical University, Nanjing, 639, Longmian Road, Nanjing 211198 (China); Jiangsu Provincial Key Laboratory for TCM Evaluation and Translational Research, China Pharmaceutical University, 639, Longmian Road, Nanjing 211198 (China); Ma, Shiping, E-mail: spma@cpu.edu.cn [Department of Pharmacology of Chinese Materia Medica, China Pharmaceutical University, Nanjing, 639, Longmian Road, Nanjing 211198 (China); Jiangsu Provincial Key Laboratory for TCM Evaluation and Translational Research, China Pharmaceutical University, 639, Longmian Road, Nanjing 211198 (China)

    2015-07-01

    Curcumin is a natural polyphenolic compound in Curcuma longa with beneficial effects on neuronal protection. This study aims to investigate the action of curcumin in the hippocampus subjected to glutamate neurotoxicity. Glutamate stimulation induced reactive oxygen species (ROS), endoplasmic reticulum stress (ER stress) and TXNIP/NLRP3 inflammasome activation, leading to damage in the hippocampus. Curcumin treatment in the hippocampus or SH-SY5Y cells inhibited IRE1α and PERK phosphorylation with suppression of intracellular ROS production. Curcumin increased AMPK activity and knockdown of AMPKα with specific siRNA abrogated its inhibitory effects on IRE1α and PERK phosphorylation, indicating that AMPK activity was essential for the suppression of ER stress. As a result, curcumin reduced TXNIP expression and inhibited NLRP3 inflammasome activation by downregulation of NLRP3 and cleaved caspase-1 induction, and thus reduced IL-1β secretion. Specific fluorescent probe and flow cytometry analysis showed that curcumin prevented mitochondrial malfunction and protected cell survival from glutamate neurotoxicity. Moreover, oral administration of curcumin reduced brain infarct volume and attenuated neuronal damage in rats subjected to middle cerebral artery occlusion. Immunohistochemistry showed that curcumin inhibited p-IRE1α, p-PERK and NLRP3 expression in hippocampus CA1 region. Together, these results showed that curcumin attenuated glutamate neurotoxicity by inhibiting ER stress-associated TXNIP/NLRP3 inflammasome activation via the regulation of AMPK, and thereby protected the hippocampus from ischemic insult. - Highlights: • Curcumin attenuates glutamate neurotoxicity in the hippocampus. • Curcumin suppresses ER stress in glutamate-induced hippocampus slices. • Curcumin inhibits TXNIP/NLRP3 inflammasome activation. • Regulation of AMPK by curcumin contributes to suppressing ER stress.

  15. Curcumin attenuates glutamate neurotoxicity in the hippocampus by suppression of ER stress-associated TXNIP/NLRP3 inflammasome activation in a manner dependent on AMPK

    International Nuclear Information System (INIS)

    Li, Ying; Li, Jia; Li, Shanshan; Li, Yi; Wang, Xiangxiang; Liu, Baolin; Fu, Qiang; Ma, Shiping

    2015-01-01

    Curcumin is a natural polyphenolic compound in Curcuma longa with beneficial effects on neuronal protection. This study aims to investigate the action of curcumin in the hippocampus subjected to glutamate neurotoxicity. Glutamate stimulation induced reactive oxygen species (ROS), endoplasmic reticulum stress (ER stress) and TXNIP/NLRP3 inflammasome activation, leading to damage in the hippocampus. Curcumin treatment in the hippocampus or SH-SY5Y cells inhibited IRE1α and PERK phosphorylation with suppression of intracellular ROS production. Curcumin increased AMPK activity and knockdown of AMPKα with specific siRNA abrogated its inhibitory effects on IRE1α and PERK phosphorylation, indicating that AMPK activity was essential for the suppression of ER stress. As a result, curcumin reduced TXNIP expression and inhibited NLRP3 inflammasome activation by downregulation of NLRP3 and cleaved caspase-1 induction, and thus reduced IL-1β secretion. Specific fluorescent probe and flow cytometry analysis showed that curcumin prevented mitochondrial malfunction and protected cell survival from glutamate neurotoxicity. Moreover, oral administration of curcumin reduced brain infarct volume and attenuated neuronal damage in rats subjected to middle cerebral artery occlusion. Immunohistochemistry showed that curcumin inhibited p-IRE1α, p-PERK and NLRP3 expression in hippocampus CA1 region. Together, these results showed that curcumin attenuated glutamate neurotoxicity by inhibiting ER stress-associated TXNIP/NLRP3 inflammasome activation via the regulation of AMPK, and thereby protected the hippocampus from ischemic insult. - Highlights: • Curcumin attenuates glutamate neurotoxicity in the hippocampus. • Curcumin suppresses ER stress in glutamate-induced hippocampus slices. • Curcumin inhibits TXNIP/NLRP3 inflammasome activation. • Regulation of AMPK by curcumin contributes to suppressing ER stress

  16. Environmental Education Activities to Enhance Decision-Making.

    Science.gov (United States)

    Yambert, Paul A.; And Others

    This document contains a set of 10 activities that teachers may use with students (ages 10 to adult) to enhance environmental knowledge and environmentally responsible behavior. Sample worksheets are included when applicable. The activities focus on: renewable and nonrenewable resources; recycling; population growth; wildlife; recycling in a…

  17. Strong eukaryotic IRESs have weak secondary structure.

    Directory of Open Access Journals (Sweden)

    Xuhua Xia

    Full Text Available BACKGROUND: The objective of this work was to investigate the hypothesis that eukaryotic Internal Ribosome Entry Sites (IRES lack secondary structure and to examine the generality of the hypothesis. METHODOLOGY/PRINCIPAL FINDINGS: IRESs of the yeast and the fruit fly are located in the 5'UTR immediately upstream of the initiation codon. The minimum folding energy (MFE of 60 nt RNA segments immediately upstream of the initiation codons was calculated as a proxy of secondary structure stability. MFE of the reverse complements of these 60 nt segments was also calculated. The relationship between MFE and empirically determined IRES activity was investigated to test the hypothesis that strong IRES activity is associated with weak secondary structure. We show that IRES activity in the yeast and the fruit fly correlates strongly with the structural stability, with highest IRES activity found in RNA segments that exhibit the weakest secondary structure. CONCLUSIONS: We found that a subset of eukaryotic IRESs exhibits very low secondary structure in the 5'-UTR sequences immediately upstream of the initiation codon. The consistency in results between the yeast and the fruit fly suggests a possible shared mechanism of cap-independent translation initiation that relies on an unstructured RNA segment.

  18. Enhancing specific-antibody production to the ragB vaccine with GITRL that expand Tfh, IFN-γ(+ T cells and attenuates Porphyromonas gingivalis infection in mice.

    Directory of Open Access Journals (Sweden)

    Dong Zheng

    Full Text Available The outer membrane protein RagB is one of the major virulence factors of the periodontal pathogen Porphyromonas gingivalis (P. gingivalis. In order to induce protective immune response against P. gingivalis infection, an mGITRL gene-linked ragB DNA vaccine (pIRES-ragB-mGITRL was constructed. Six-week-old female BALB/c mice were immunized with pIRES-ragB-mGITRL through intramuscular injection and then challenged by subcutaneous injection in the abdomen with P. gingivalis. RagB-specific antibody-forming cells were evaluated by an Enzyme-linked immunosorbent spot, and specific antibody was determined by enzyme-linked immunosorbent assay. In addition, the frequencies of Tfh and IFN-γ(+ T cells in spleen were measured using flow cytometer, and the levels of IL-21 and IFN-γ mRNA or proteins were detected by real time RT-PCR or ELISA. The data showed that the mGITRL-linked ragB DNA vaccine induced higher levels of RagB-specific IgG in serum and RagB-specific antibody-forming cells in spleen. The frequencies of Tfh and IFN-γ(+ T cells were obviously expanded in mice immunized by pIRES-ragB-mGITRL compared with other groups (pIRES or pIRES-ragB . The levels of Tfh and IFN-γ(+ T cells associated cytokines were also significantly increased in pIRES-ragB-mGITRL group. Therefore, the mice immunized with ragB plus mGITRL showed the stronger resistant to P. gingivalis infection and a significant reduction of the lesion size caused by P. gingivalis infection comparing with other groups. Taken together, our findings demonstrated that intramuscular injection of DNA vaccine ragB together with mGITRL induced protective immune response dramatically by increasing Tfh and IFN-γ(+ T cells and antibody production to P. gingivalis.

  19. ChIP-seq Accurately Predicts Tissue-Specific Activity of Enhancers

    Energy Technology Data Exchange (ETDEWEB)

    Visel, Axel; Blow, Matthew J.; Li, Zirong; Zhang, Tao; Akiyama, Jennifer A.; Holt, Amy; Plajzer-Frick, Ingrid; Shoukry, Malak; Wright, Crystal; Chen, Feng; Afzal, Veena; Ren, Bing; Rubin, Edward M.; Pennacchio, Len A.

    2009-02-01

    A major yet unresolved quest in decoding the human genome is the identification of the regulatory sequences that control the spatial and temporal expression of genes. Distant-acting transcriptional enhancers are particularly challenging to uncover since they are scattered amongst the vast non-coding portion of the genome. Evolutionary sequence constraint can facilitate the discovery of enhancers, but fails to predict when and where they are active in vivo. Here, we performed chromatin immunoprecipitation with the enhancer-associated protein p300, followed by massively-parallel sequencing, to map several thousand in vivo binding sites of p300 in mouse embryonic forebrain, midbrain, and limb tissue. We tested 86 of these sequences in a transgenic mouse assay, which in nearly all cases revealed reproducible enhancer activity in those tissues predicted by p300 binding. Our results indicate that in vivo mapping of p300 binding is a highly accurate means for identifying enhancers and their associated activities and suggest that such datasets will be useful to study the role of tissue-specific enhancers in human biology and disease on a genome-wide scale.

  20. The Running Wheel Enhances Food Anticipatory Activity: An Exploratory Study.

    Science.gov (United States)

    Flôres, Danilo E F L; Bettilyon, Crystal N; Jia, Lori; Yamazaki, Shin

    2016-01-01

    Rodents anticipate rewarding stimuli such as daily meals, mates, and stimulant drugs. When a single meal is provided daily at a fixed time of day, an increase in activity, known as food anticipatory activity (FAA), occurs several hours before feeding time. The factors affecting the expression of FAA have not been well-studied. Understanding these factors may provide clues to the undiscovered anatomical substrates of food entrainment. In this study we determined whether wheel-running activity, which is also rewarding to rodents, modulated the robustness of FAA. We found that access to a freely rotating wheel enhanced the robustness of FAA. This enhancement was lost when the wheel was removed. In addition, while prior exposure to a running wheel alone did not enhance FAA, the presence of a locked wheel did enhance FAA as long as mice had previously run in the wheel. Together, these data suggest that FAA, like wheel-running activity, is influenced by reward signaling.

  1. Distinct roles for the IIId2 sub-domain in pestivirus and picornavirus internal ribosome entry sites.

    Science.gov (United States)

    Willcocks, Margaret M; Zaini, Salmah; Chamond, Nathalie; Ulryck, Nathalie; Allouche, Delphine; Rajagopalan, Noemie; Davids, Nana A; Fahnøe, Ulrik; Hadsbjerg, Johanne; Rasmussen, Thomas Bruun; Roberts, Lisa O; Sargueil, Bruno; Belsham, Graham J; Locker, Nicolas

    2017-12-15

    Viral internal ribosomes entry site (IRES) elements coordinate the recruitment of the host translation machinery to direct the initiation of viral protein synthesis. Within hepatitis C virus (HCV)-like IRES elements, the sub-domain IIId(1) is crucial for recruiting the 40S ribosomal subunit. However, some HCV-like IRES elements possess an additional sub-domain, termed IIId2, whose function remains unclear. Herein, we show that IIId2 sub-domains from divergent viruses have different functions. The IIId2 sub-domain present in Seneca valley virus (SVV), a picornavirus, is dispensable for IRES activity, while the IIId2 sub-domains of two pestiviruses, classical swine fever virus (CSFV) and border disease virus (BDV), are required for 80S ribosomes assembly and IRES activity. Unlike in SVV, the deletion of IIId2 from the CSFV and BDV IRES elements impairs initiation of translation by inhibiting the assembly of 80S ribosomes. Consequently, this negatively affects the replication of CSFV and BDV. Finally, we show that the SVV IIId2 sub-domain is required for efficient viral RNA synthesis and growth of SVV, but not for IRES function. This study sheds light on the molecular evolution of viruses by clearly demonstrating that conserved RNA structures, within distantly related RNA viruses, have acquired different roles in the virus life cycles. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.

  2. Ficus Deltoidea Enhance Glucose Uptake Activity in Cultured Muscle Cells

    International Nuclear Information System (INIS)

    Zainah Adam; Shafii Khamis; Amin Ismail; Muhajir Hamid

    2015-01-01

    Ficus deltoidea or locally known as Mas cotek is one of the common medicinal plants used in Malaysia. Our previous studies showed that this plant have blood glucose lowering effect. Glucose uptake into muscle and adipocytes cells is one of the known mechanisms of blood glucose lowering effect. This study was performed to evaluate the effect of Ficus deltoidea on glucose uptake activity into muscle cells. The cells were incubated with Ficus deltoidea extracts either alone or combination with insulin. Amount of glucose uptake by L6 myotubes was determined using glucose tracer, 2-deoxy-(1- 3 H 1 )-glucose. The results showed that Ficus deltoidea extracts at particular doses enhanced basal or insulin-mediated glucose uptake into muscle cells significantly. Hot aqueous extract enhanced glucose uptake at the low concentration (10 μg/ ml) whereas methanolic extract enhanced glucose uptake at low and high concentrations. Methanolic extract also mimicked insulin activity during enhancing glucose uptake into L^ muscle cells. Glucose uptake activity of Ficus deltoidea could be attributed by the phenolic compound presence in the plant. This study had shown that Ficus deltoidea has the ability to enhance glucose uptake into muscle cells which is partly contributed the antidiabetic activity of this plant. (author)

  3. VESPA. Behaviour of long-lived fission and activation products in the nearfield of a nuclear waste repository and the possibilities of their retention

    Energy Technology Data Exchange (ETDEWEB)

    Bischofer, Barbara; Hagemann, Sven [Gesellschaft fuer Anlagen- und Reaktorsicherheit (GRS) gGmbH, Koeln (Germany); Altmaier, Marcus [Karlsruher Institut fuer Technologie (KIT) (Germany); and others

    2016-06-15

    The present document is the final report of the Joint Research Project VESPA (Behaviour of Long-lived Fission and Activation Products in the Near Field of a Nuclear Waste Repository and the Possibilities of Their Retention), started in July 2010 with a duration of four years. The following four institutions were collaborative Partners in VESPA: - Gesellschaft fuer Anlagen- und Reaktorsicherheit (GRS) gGmbH - Institut fuer Energie- und Klimaforschung, IEK-6: Nukleare Entsorgung und Reaktorsicherheit, Forschungszentrum Juelich (FZJ) - Institut fuer Ressourcenoekologie (IRE), Helmholtz-Zentrum Dresden-Rossendorf (HZDR) - Institut fuer Nukleare Entsorgung (INE), Karlsruher Institut fuer Technologie (KIT) VESPA was funded by the German Federal Ministry of Economics and Energy (BMWi) under the contract numbers 02 E 10770 (GRS), 02 E 10780 (FZJ-IEF-6), 02 E 10790 (HZDR-IRE), 02 E 10800 (KIT-INE).

  4. Functional assessment of human enhancer activities using whole-genome STARR-sequencing.

    Science.gov (United States)

    Liu, Yuwen; Yu, Shan; Dhiman, Vineet K; Brunetti, Tonya; Eckart, Heather; White, Kevin P

    2017-11-20

    Genome-wide quantification of enhancer activity in the human genome has proven to be a challenging problem. Recent efforts have led to the development of powerful tools for enhancer quantification. However, because of genome size and complexity, these tools have yet to be applied to the whole human genome.  In the current study, we use a human prostate cancer cell line, LNCaP as a model to perform whole human genome STARR-seq (WHG-STARR-seq) to reliably obtain an assessment of enhancer activity. This approach builds upon previously developed STARR-seq in the fly genome and CapSTARR-seq techniques in targeted human genomic regions. With an improved library preparation strategy, our approach greatly increases the library complexity per unit of starting material, which makes it feasible and cost-effective to explore the landscape of regulatory activity in the much larger human genome. In addition to our ability to identify active, accessible enhancers located in open chromatin regions, we can also detect sequences with the potential for enhancer activity that are located in inaccessible, closed chromatin regions. When treated with the histone deacetylase inhibitor, Trichostatin A, genes nearby this latter class of enhancers are up-regulated, demonstrating the potential for endogenous functionality of these regulatory elements. WHG-STARR-seq provides an improved approach to current pipelines for analysis of high complexity genomes to gain a better understanding of the intricacies of transcriptional regulation.

  5. The Specificity of Innate Immune Responses Is Enforced by Repression of Interferon Response Elements by NF-κB p50

    Science.gov (United States)

    Cheng, Christine S.; Feldman, Kristyn E.; Lee, James; Verma, Shilpi; Huang, De-Bin; Huynh, Kim; Chang, Mikyoung; Ponomarenko, Julia V.; Sun, Shao-Cong; Benedict, Chris A.; Ghosh, Gourisankar; Hoffmann, Alexander

    2011-01-01

    The specific binding of transcription factors to cognate sequence elements is thought to be critical for the generation of specific gene expression programs. Members of the nuclear factor κB (NF-κB) and interferon (IFN) regulatory factor (IRF) transcription factor families bind to the κB site and the IFN response element (IRE), respectively, of target genes, and they are activated in macrophages after exposure to pathogens. However, how these factors produce pathogen-specific inflammatory and immune responses remains poorly understood. Combining top-down and bottom-up systems biology approaches, we have identified the NF-κB p50 homodimer as a regulator of IRF responses. Unbiased genome-wide expression and biochemical and structural analyses revealed that the p50 homodimer repressed a subset of IFN-inducible genes through a previously uncharacterized subclass of guanine-rich IRE (G-IRE) sequences. Mathematical modeling predicted that the p50 homodimer might enforce the stimulus specificity of composite promoters. Indeed, the production of the antiviral regulator IFN-β was rendered stimulus-specific by the binding of the p50 homodimer to the G-IRE–containing IFNβ enhancer to suppress cytotoxic IFN signaling. Specifically, a deficiency in p50 resulted in the inappropriate production of IFN-β in response to bacterial DNA sensed by Toll-like receptor 9. This role for the NF-κB p50 homodimer in enforcing the specificity of the cellular response to pathogens by binding to a subset of IRE sequences alters our understanding of how the NF-κB and IRF signaling systems cooperate to regulate antimicrobial immunity. PMID:21343618

  6. The internal initiation of translation in bovine viral diarrhea virus RNA depends on the presence of an RNA pseudoknot upstream of the initiation codon.

    Science.gov (United States)

    Moes, Lorin; Wirth, Manfred

    2007-11-22

    Bovine viral diarrhea virus (BVDV) is the prototype representative of the pestivirus genus in the Flaviviridae family. It has been shown that the initiation of translation of BVDV RNA occurs by an internal ribosome entry mechanism mediated by the 5' untranslated region of the viral RNA 1. The 5' and 3' boundaries of the IRES of the cytopathic BVDV NADL have been mapped and it has been suggested that the IRES extends into the coding of the BVDV polyprotein 2. A putative pseudoknot structure has been recognized in the BVDV 5'UTR in close proximity to the AUG start codon. A pseudoknot structure is characteristic for flavivirus IRESes and in the case of the closely related classical swine fever virus (CSFV) and the more distantly related Hepatitis C virus (HCV) pseudoknot function in translation has been demonstrated. To characterize the BVDV IRESes in detail, we studied the BVDV translational initiation by transfection of dicistronic expression plasmids into mammalian cells. A region coding for the amino terminus of the BVDV SD-1 polyprotein contributes considerably to efficient initiation of translation. The translation efficiency mediated by the IRES of BVDV strains NADL and SD-1 approximates the poliovirus type I IRES directed translation in BHK cells. Compared to the poliovirus IRES increased expression levels are mediated by the BVDV IRES of strain SD-1 in murine cell lines, while lower levels are observed in human cell lines. Site directed mutagenesis revealed that a RNA pseudoknot upstream of the initiator AUG is an important structural element for IRES function. Mutants with impaired ability to base pair in stem I or II lost their translational activity. In mutants with repaired base pairing either in stem 1 or in stem 2 full translational activity was restored. Thus, the BVDV IRES translation is dependent on the pseudoknot integrity. These features of the pestivirus IRES are reminiscent of those of the classical swine fever virus, a pestivirus, and the

  7. The internal initiation of translation in bovine viral diarrhea virus RNA depends on the presence of an RNA pseudoknot upstream of the initiation codon

    Directory of Open Access Journals (Sweden)

    Moes Lorin

    2007-11-01

    Full Text Available Abstract Background Bovine viral diarrhea virus (BVDV is the prototype representative of the pestivirus genus in the Flaviviridae family. It has been shown that the initiation of translation of BVDV RNA occurs by an internal ribosome entry mechanism mediated by the 5' untranslated region of the viral RNA 1. The 5' and 3' boundaries of the IRES of the cytopathic BVDV NADL have been mapped and it has been suggested that the IRES extends into the coding of the BVDV polyprotein 2. A putative pseudoknot structure has been recognized in the BVDV 5'UTR in close proximity to the AUG start codon. A pseudoknot structure is characteristic for flavivirus IRESes and in the case of the closely related classical swine fever virus (CSFV and the more distantly related Hepatitis C virus (HCV pseudoknot function in translation has been demonstrated. Results To characterize the BVDV IRESes in detail, we studied the BVDV translational initiation by transfection of dicistronic expression plasmids into mammalian cells. A region coding for the amino terminus of the BVDV SD-1 polyprotein contributes considerably to efficient initiation of translation. The translation efficiency mediated by the IRES of BVDV strains NADL and SD-1 approximates the poliovirus type I IRES directed translation in BHK cells. Compared to the poliovirus IRES increased expression levels are mediated by the BVDV IRES of strain SD-1 in murine cell lines, while lower levels are observed in human cell lines. Site directed mutagenesis revealed that a RNA pseudoknot upstream of the initiator AUG is an important structural element for IRES function. Mutants with impaired ability to base pair in stem I or II lost their translational activity. In mutants with repaired base pairing either in stem 1 or in stem 2 full translational activity was restored. Thus, the BVDV IRES translation is dependent on the pseudoknot integrity. These features of the pestivirus IRES are reminiscent of those of the classical

  8. MR and CT imaging characteristics and ablation zone volumetry of locally advanced pancreatic cancer treated with irreversible electroporation

    Energy Technology Data Exchange (ETDEWEB)

    Vroomen, Laurien G.P.H.; Scheffer, Hester J.; Melenhorst, Marleen C.A.M.; Jong, Marcus C. de; Bergh, Janneke E. van den; Kuijk, Cornelis van; Meijerink, Martijn R. [VU University Medical Center, Department of Radiology and Nuclear Medicine, Amsterdam (Netherlands); Delft, Foke van [VU University Medical Center, Department of Gastroenterology and Hepatology, Amsterdam (Netherlands); Kazemier, Geert [VU University Medical Center, Department of Surgery, Amsterdam (Netherlands)

    2017-06-15

    To assess specific imaging characteristics after irreversible electroporation (IRE) for locally advanced pancreatic carcinoma (LAPC) with contrast-enhanced (ce)MRI and ceCT, and to explore the correlation of these characteristics with the development of recurrence. Qualitative and quantitative analyses of imaging data were performed on 25 patients treated with percutaneous IRE for LAPC. Imaging characteristics of the ablation zone on ceCT and ceMRI were assessed over a 6-month follow-up period. Contrast ratio scores between pre- and post-treatment were compared. To detect early imaging markers for treatment failure, attenuation characteristics at 6 weeks were linked to the area of recurrence within 6 months. Post-IRE, diffusion-weighted imaging (DWI)-b800 signal intensities decreased in all cases (p < 0.05). Both ceMRI and ceCT revealed absent or decreased contrast enhancement, with a hyperintense rim on ceMRI. Ablation zone volume increase was noted on both modalities in the first 6 weeks, followed by a decrease (p < 0.05). In the patients developing tumour recurrence (5/25), a focal DWI-b800 hyperintense spot at 6 weeks predated unequivocal recurrence on CT. The most remarkable signal alterations after pancreatic IRE were shown by DWI-b800 and ceMRI. These early imaging characteristics may be useful to establish technical success and predict treatment outcome. (orig.)

  9. Xenobiotics enhance laccase activity in alkali-tolerant γ-proteobacterium JB.

    Science.gov (United States)

    Singh, Gursharan; Batish, Mona; Sharma, Prince; Capalash, Neena

    2009-01-01

    Various genotoxic textile dyes, xenobiotics, substrates (10 µM) and agrochemicals (100 µg/ml) were tested for enhancement of alkalophilic laccase activity in γ-proteobacterium JB. Neutral Red, Indigo Carmine, Naphthol Base Bordears and Sulphast Ruby dyes increased the activity by 3.7, 2.7, 2.6 and 2.3 fold respectively. Xenobiotics/substrates like p-toluidine, 8-hydroxyquinoline and anthracine increased it by 3.4, 2.8 and 2.3 fold respectively. Atrazine and trycyclozole pesticides enhanced the activity by 1.95 and 1.5 fold respectively.

  10. "A Separation Theorem of Active Management and Synthetic Enhanced Active Strategies"(in Japanese)

    OpenAIRE

    Takao Kobayashi; Seiji Minami

    2008-01-01

    We propose a Separation Theorem of Active Management. It asserts that in the so-called Enhanced Active Portfolio framework the efficient frontier is linear in the active return/active risk space, and one can separate the determination of optimal active portfolio weights from the determination of optimal leverage ratio. The risk preference of investors does not play any role in the former decision. The theorem holds under a fairly general set of conditions on portfolio restrictions. As such it...

  11. Enhancement of hypoxia-activated prodrug TH-302 anti-tumor activity by Chk1 inhibition.

    Science.gov (United States)

    Meng, Fanying; Bhupathi, Deepthi; Sun, Jessica D; Liu, Qian; Ahluwalia, Dharmendra; Wang, Yan; Matteucci, Mark D; Hart, Charles P

    2015-05-21

    The hypoxia-activated prodrug TH-302 is reduced at its nitroimidazole group and selectively under hypoxic conditions releases the DNA cross-linker bromo-isophosphoramide mustard (Br-IPM). Here, we have explored the effect of Chk1 inhibition on TH-302-mediated pharmacological activities. We employed in vitro cell viability, DNA damage, cellular signaling assays and the in vivo HT29 human tumor xenograft model to study the effect of Chk1inhibition on TH-302 antitumor activities. TH-302 cytotoxicity is greatly enhanced by Chk1 inhibition in p53-deficient but not in p53-proficient human cancer cell lines. Chk1 inhibitors reduced TH-302-induced cell cycle arrest via blocking TH-302-induced decrease of phosphorylation of histone H3 and increasing Cdc2-Y15 phosphorylation. Employing the single-cell gel electrophoresis (comet) assay, we observed a potentiation of the TH-302 dependent tail moment. TH-302 induced γH2AX and apoptosis were also increased upon the addition of Chk1 inhibitor. Potentiation of TH-302 cytotoxicity by Chk1 inhibitor was only observed in cell lines proficient in, but not deficient in homology-directed DNA repair. We also show that combination treatment led to lowering of Rad51 expression levels as compared to either agent alone. In vivo data demonstrate that Chk1 inhibitor enhances TH-302 anti-tumor activity in p53 mutant HT-29 human tumor xenografts, supporting the hypothesis that these in vitro results can translate to enhanced in vivo efficacy of the combination. TH-302-mediated in vitro and in vivo anti-tumor activities were greatly enhanced by the addition of Chk1 inhibitors. The preclinical data presented in this study support a new approach for the treatment of p53-deficient hypoxic cancers by combining Chk1 inhibitors with the hypoxia-activated prodrug TH-302.

  12. Mechanisms of morphine enhancement of spontaneous seizure activity.

    Science.gov (United States)

    Saboory, Ehsan; Derchansky, Miron; Ismaili, Mohammed; Jahromi, Shokrollah S; Brull, Richard; Carlen, Peter L; El Beheiry, Hossam

    2007-12-01

    High-dose opioid therapy can precipitate seizures; however, the mechanism of such a dangerous adverse effect remains poorly understood. The aim of our study was to determine whether the neuroexcitatory activity of high-dose morphine is mediated by selective stimulation of opioid receptors. Mice hippocampi were resected intact and bathed in low magnesium artificial cerebrospinal fluid to induce spontaneous seizure-like events recorded from CA1 neurons. Application of morphine had a biphasic effect on the recorded spontaneous seizure-like events. In a low concentration (10 microM), morphine depressed electrographic seizure activity. Higher morphine concentrations (30 and 100 microM) enhanced seizure activity in an apparent dose-dependent manner. Naloxone, a nonselective opiate antagonist blocked the proconvulsant action of morphine. Selective mu and kappa opiate receptor agonists and antagonists enhanced and suppressed the spontaneous seizure activity, respectively. On the contrary, delta opioid receptor ligands did not have an effect. The proseizure effect of morphine is mediated through selective stimulation of mu and kappa opiate receptors but not the activation of the delta receptor system. The observed dose-dependent mechanism of morphine neuroexcitation underscores careful adjustment and individualized opioid dosing in the clinical setting.

  13. Gramicidin D enhances the antibacterial activity of fluoride

    OpenAIRE

    Nelson, James W.; Zhou, Zhiyuan; Breaker, Ronald R.

    2014-01-01

    Fluoride is a toxic anion found in many natural environments. One of the major bacterial defenses against fluoride is the cell envelope, which limits passage of the membrane-impermeant fluoride anion. Accordingly, compounds that enhance the permeability of bacterial membranes to fluoride should also enhance fluoride toxicity. In this study, we demonstrate that the pore-forming antibiotic gramicidin D increases fluoride uptake in B. subtilis and that the antibacterial activity of this compound...

  14. An internal ribosome entry site directs translation of the 3'-gene from Pelargonium flower break virus genomic RNA: implications for infectivity.

    Directory of Open Access Journals (Sweden)

    Olga Fernández-Miragall

    Full Text Available Pelargonium flower break virus (PFBV, genus Carmovirus has a single-stranded positive-sense genomic RNA (gRNA which contains five ORFs. The two 5'-proximal ORFs encode the replicases, two internal ORFs encode movement proteins, and the 3'-proximal ORF encodes a polypeptide (p37 which plays a dual role as capsid protein and as suppressor of RNA silencing. Like other members of family Tombusviridae, carmoviruses express ORFs that are not 5'-proximal from subgenomic RNAs. However, in one case, corresponding to Hisbiscus chlorotic ringspot virus, it has been reported that the 3'-proximal gene can be translated from the gRNA through an internal ribosome entry site (IRES. Here we show that PFBV also holds an IRES that mediates production of p37 from the gRNA, raising the question of whether this translation strategy may be conserved in the genus. The PFBV IRES was functional both in vitro and in vivo and either in the viral context or when inserted into synthetic bicistronic constructs. Through deletion and mutagenesis studies we have found that the IRES is contained within a 80 nt segment and have identified some structural traits that influence IRES function. Interestingly, mutations that diminish IRES activity strongly reduced the infectivity of the virus while the progress of the infection was favoured by mutations potentiating such activity. These results support the biological significance of the IRES-driven p37 translation and suggest that production of the silencing suppressor from the gRNA might allow the virus to early counteract the defence response of the host, thus facilitating pathogen multiplication and spread.

  15. An internal ribosome entry site directs translation of the 3'-gene from Pelargonium flower break virus genomic RNA: implications for infectivity.

    Science.gov (United States)

    Fernández-Miragall, Olga; Hernández, Carmen

    2011-01-01

    Pelargonium flower break virus (PFBV, genus Carmovirus) has a single-stranded positive-sense genomic RNA (gRNA) which contains five ORFs. The two 5'-proximal ORFs encode the replicases, two internal ORFs encode movement proteins, and the 3'-proximal ORF encodes a polypeptide (p37) which plays a dual role as capsid protein and as suppressor of RNA silencing. Like other members of family Tombusviridae, carmoviruses express ORFs that are not 5'-proximal from subgenomic RNAs. However, in one case, corresponding to Hisbiscus chlorotic ringspot virus, it has been reported that the 3'-proximal gene can be translated from the gRNA through an internal ribosome entry site (IRES). Here we show that PFBV also holds an IRES that mediates production of p37 from the gRNA, raising the question of whether this translation strategy may be conserved in the genus. The PFBV IRES was functional both in vitro and in vivo and either in the viral context or when inserted into synthetic bicistronic constructs. Through deletion and mutagenesis studies we have found that the IRES is contained within a 80 nt segment and have identified some structural traits that influence IRES function. Interestingly, mutations that diminish IRES activity strongly reduced the infectivity of the virus while the progress of the infection was favoured by mutations potentiating such activity. These results support the biological significance of the IRES-driven p37 translation and suggest that production of the silencing suppressor from the gRNA might allow the virus to early counteract the defence response of the host, thus facilitating pathogen multiplication and spread.

  16. Vitamin D Promotes Protein Homeostasis and Longevity via the Stress Response Pathway Genes skn-1, ire-1, and xbp-1

    Directory of Open Access Journals (Sweden)

    Karla A. Mark

    2016-10-01

    Full Text Available Vitamin D has multiple roles, including the regulation of bone and calcium homeostasis. Deficiency of 25-hydroxyvitamin D, the major circulating form of vitamin D, is associated with an increased risk of age-related chronic diseases, including Alzheimer’s disease, Parkinson’s disease, cognitive impairment, and cancer. In this study, we utilized Caenorhabditis elegans to examine the mechanism by which vitamin D influences aging. We found that vitamin-D3-induced lifespan extension requires the stress response pathway genes skn-1, ire-1, and xbp-1. Vitamin D3 (D3 induced expression of SKN-1 target genes but not canonical targets of XBP-1. D3 suppressed an important molecular pathology of aging, that of widespread protein insolubility, and prevented toxicity caused by human β-amyloid. Our observation that D3 improves protein homeostasis and slows aging highlights the importance of maintaining appropriate vitamin D serum levels and may explain why such a wide variety of human age-related diseases are associated with vitamin D deficiency.

  17. Active and Inactive Enhancers Cooperate to Exert Localized and Long-Range Control of Gene Regulation

    Directory of Open Access Journals (Sweden)

    Charlotte Proudhon

    2016-06-01

    Full Text Available V(DJ recombination relies on the presence of proximal enhancers that activate the antigen receptor (AgR loci in a lineage- and stage-specific manner. Unexpectedly, we find that both active and inactive AgR enhancers cooperate to disseminate their effects in a localized and long-range manner. Here, we demonstrate the importance of short-range contacts between active enhancers that constitute an Igk super-enhancer in B cells. Deletion of one element reduces the interaction frequency between other enhancers in the hub, which compromises the transcriptional output of each component. Furthermore, we establish that, in T cells, long-range contact and cooperation between the inactive Igk enhancer MiEκ and the active Tcrb enhancer Eβ alters enrichment of CBFβ binding in a manner that impacts Tcrb recombination. These findings underline the complexities of enhancer regulation and point to a role for localized and long-range enhancer-sharing between active and inactive elements in lineage- and stage-specific control.

  18. Contrast-enhanced ultrasonography for the determination of Crohn's disease activity - preliminary experience.

    Science.gov (United States)

    Białecki, Marcin; Białecka, Agnieszka; Laskowska, Katarzyna; Kłopocka, Maria; Liebert, Ariel; Lemanowicz, Adam; Serafin, Zbigniew

    2014-01-01

    Contrast-enhanced ultrasound (CEUS) is a recent non-invasive modality, which may partially replace currently used techniques (endoscopy, CT enterography and MR enterography) in the diagnostics and assessment of Crohn's disease (CD). The aim of the study was to analyze early experience in the use of CEUS for the measurement of activity and staging of CD. Eleven patients previously diagnosed with CD were included in the study. They underwent contrast-enhanced ultrasonography (SonoVue, Bracco), low-dose CT enterography (LDCTE), assessment of laboratory markers of inflammation and clinical CD activity index (CDAI). Contrast enhancement was evaluated using a semi-quantitative method and a quantitative method that included measurement of peak enhancement (PE), enhancement curve rise time (RT) and wash-in-rate (WiR). Ileal wall thickening was observed in all patients. Semi-quantitative method was used to observe CD activity in CEUS in 10 cases that perfectly matched LDCTE findings. There was a moderate positive correlation between PE and CDAI (r=0.65, p<0.001). There was no significant relationship between perfusion parameters and laboratory markers of inflammation. CEUS is a promising modality for non-invasive assessment of pathologic ileal vascularization in the course of Crohn's disease. Intensity of enhancement in CEUS reflects activity of the disease detected in LDCTE and correlates with CDAI.

  19. Design of New Antibacterial Enhancers Based on AcrB’s Structure and the Evaluation of Their Antibacterial Enhancement Activity

    Directory of Open Access Journals (Sweden)

    Yi Song

    2016-11-01

    Full Text Available Previously, artesunate (AS and dihydroartemisinine 7 (DHA7 were found to have antibacterial enhancement activity against Escherichia coli via inhibition of the efflux pump AcrB. However, they were only effective against E. coli standard strains. This study aimed to develop effective antibacterial enhancers based on the previous work. Our results demonstrate that 86 new antibacterial enhancers were designed via 3D-SAR and molecular docking. Among them, DHA27 had the best antibacterial enhancement activity. It could potentiate the antibacterial effects of ampicillin against not only E. coli standard strain but also clinical strains, and of β-lactam antibiotics, not non-β-lactamantibiotics. DHA27 could increase the accumulation of daunomycin and nile red within E. coli ATCC 35218, but did not increase the bacterial membrane permeability. DHA27 reduced acrB’s mRNA expression of E. coli ATCC 35218 in a dose-dependent manner, and its antibacterial enhancement activity is related to the degree of acrB mRNA expression in E. coli clinical strains. The polypeptides from AcrB were obtained via molecular docking assay; the pre-incubated polypeptides could inhibit the activity of DHA27. Importantly, DHA27 had no cytotoxicity on cell proliferation. In conclusion, among newly designed antibacterial enhancers, DHA27 had favorable physical and pharmacological properties with no significant cytotoxicity at effective concentrations, and might serve as a potential efflux pump inhibitor in the future.

  20. Nanocaged enzymes with enhanced catalytic activity and increased stability against protease digestion

    Science.gov (United States)

    Zhao, Zhao; Fu, Jinglin; Dhakal, Soma; Johnson-Buck, Alexander; Liu, Minghui; Zhang, Ting; Woodbury, Neal W.; Liu, Yan; Walter, Nils G.; Yan, Hao

    2016-01-01

    Cells routinely compartmentalize enzymes for enhanced efficiency of their metabolic pathways. Here we report a general approach to construct DNA nanocaged enzymes for enhancing catalytic activity and stability. Nanocaged enzymes are realized by self-assembly into DNA nanocages with well-controlled stoichiometry and architecture that enabled a systematic study of the impact of both encapsulation and proximal polyanionic surfaces on a set of common metabolic enzymes. Activity assays at both bulk and single-molecule levels demonstrate increased substrate turnover numbers for DNA nanocage-encapsulated enzymes. Unexpectedly, we observe a significant inverse correlation between the size of a protein and its activity enhancement. This effect is consistent with a model wherein distal polyanionic surfaces of the nanocage enhance the stability of active enzyme conformations through the action of a strongly bound hydration layer. We further show that DNA nanocages protect encapsulated enzymes against proteases, demonstrating their practical utility in functional biomaterials and biotechnology. PMID:26861509

  1. Nanocaged enzymes with enhanced catalytic activity and increased stability against protease digestion

    Science.gov (United States)

    Zhao, Zhao; Fu, Jinglin; Dhakal, Soma; Johnson-Buck, Alexander; Liu, Minghui; Zhang, Ting; Woodbury, Neal W.; Liu, Yan; Walter, Nils G.; Yan, Hao

    2016-02-01

    Cells routinely compartmentalize enzymes for enhanced efficiency of their metabolic pathways. Here we report a general approach to construct DNA nanocaged enzymes for enhancing catalytic activity and stability. Nanocaged enzymes are realized by self-assembly into DNA nanocages with well-controlled stoichiometry and architecture that enabled a systematic study of the impact of both encapsulation and proximal polyanionic surfaces on a set of common metabolic enzymes. Activity assays at both bulk and single-molecule levels demonstrate increased substrate turnover numbers for DNA nanocage-encapsulated enzymes. Unexpectedly, we observe a significant inverse correlation between the size of a protein and its activity enhancement. This effect is consistent with a model wherein distal polyanionic surfaces of the nanocage enhance the stability of active enzyme conformations through the action of a strongly bound hydration layer. We further show that DNA nanocages protect encapsulated enzymes against proteases, demonstrating their practical utility in functional biomaterials and biotechnology.

  2. Active and Inactive Enhancers Cooperate to Exert Localized and Long-Range Control of Gene Regulation.

    Science.gov (United States)

    Proudhon, Charlotte; Snetkova, Valentina; Raviram, Ramya; Lobry, Camille; Badri, Sana; Jiang, Tingting; Hao, Bingtao; Trimarchi, Thomas; Kluger, Yuval; Aifantis, Iannis; Bonneau, Richard; Skok, Jane A

    2016-06-07

    V(D)J recombination relies on the presence of proximal enhancers that activate the antigen receptor (AgR) loci in a lineage- and stage-specific manner. Unexpectedly, we find that both active and inactive AgR enhancers cooperate to disseminate their effects in a localized and long-range manner. Here, we demonstrate the importance of short-range contacts between active enhancers that constitute an Igk super-enhancer in B cells. Deletion of one element reduces the interaction frequency between other enhancers in the hub, which compromises the transcriptional output of each component. Furthermore, we establish that, in T cells, long-range contact and cooperation between the inactive Igk enhancer MiEκ and the active Tcrb enhancer Eβ alters enrichment of CBFβ binding in a manner that impacts Tcrb recombination. These findings underline the complexities of enhancer regulation and point to a role for localized and long-range enhancer-sharing between active and inactive elements in lineage- and stage-specific control. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.

  3. Growth enhancement and gene expression of Arabidopsis thaliana irradiated with active oxygen species

    Science.gov (United States)

    Watanabe, Satoshi; Ono, Reoto; Hayashi, Nobuya; Shiratani, Masaharu; Tashiro, Kosuke; Kuhara, Satoru; Inoue, Asami; Yasuda, Kaori; Hagiwara, Hiroko

    2016-07-01

    The characteristics of plant growth enhancement effect and the mechanism of the enhancement induced by plasma irradiation are investigated using various active species in plasma. Active oxygen species in oxygen plasma are effective for growth enhancement of plants. DNA microarray analysis of Arabidopsis thaliana indicates that the genes coding proteins that counter oxidative stresses by eliminating active oxygen species are expressed at significantly high levels. The size of plant cells increases owing to oxygen plasma irradiation. The increases in gene expression levels and cell size suggest that the increase in the expression level of the expansin protein is essential for plant growth enhancement phenomena.

  4. Regulation of hepatitis B virus ENI enhancer activity by hepatocyte-enriched transcription factor HNF3.

    Science.gov (United States)

    Chen, M; Hieng, S; Qian, X; Costa, R; Ou, J H

    1994-11-15

    Hepatitis B virus (HBV) ENI enhancer can activate the expression of HBV and non-HBV genes in a liver-specific manner. By performing the electrophoretic mobility-shift assays, we demonstrated that the three related, liver-enriched, transcription factors, HNF3 alpha, HNF3 beta, and HNF3 gamma could all bind to the 2c site of HBV ENI enhancer. Mutations introduced in the 2c site to abolish the binding by HNF3 reduced the enhancer activity approximately 15-fold. Moreover, expression of HNF3 antisense sequences to suppress the expression of HNF3 in Huh-7 hepatoma cells led to reduction of the ENI enhancer activity. These results indicate that HNF3 positively regulates the ENI enhancer activity and this regulation is most likely mediated through the 2c site. The requirement of HNF3 for the ENI enhancer activity could explain the liver specificity of this enhancer element.

  5. Hypothyroidism Causes Endoplasmic Reticulum Stress in Adult Rat Hippocampus: A Mechanism Associated with Hippocampal Damage

    Directory of Open Access Journals (Sweden)

    Alejandra Paola Torres-Manzo

    2018-01-01

    Full Text Available Thyroid hormones (TH are essential for hippocampal neuronal viability in adulthood, and their deficiency causes hypothyroidism, which is related to oxidative stress events and neuronal damage. Also, it has been hypothesized that hypothyroidism causes a glucose deprivation in the neuron. This study is aimed at evaluating the temporal participation of the endoplasmic reticulum stress (ERE in hippocampal neurons of adult hypothyroid rats and its association with the oxidative stress events. Adult Wistar male rats were divided into euthyroid and hypothyroid groups. Thyroidectomy with parathyroid gland reimplementation caused hypothyroidism at three weeks postsurgery. Oxidative stress, redox environment, and antioxidant enzyme markers, as well as the expression of the ERE through the pathways of PERK, ATF6, and IRE1, were evaluated at the 3rd and 4th weeks postsurgery. We found a rise in ROS and nitrite production; also, catalase increased and glutathione peroxidase diminished their activities. These events promote an enhancement of the lipoperoxidation, as well as of γ-GT, myeloperoxidase, and caspase 3 activities. With respect to ERE, there were ATF6, IRE1, and GADD153 overexpressions with a reduction in mitochondrial activity and GSH2/GSSG ratio. We conclude that the endoplasmic reticulum stress might play a pivotal role in the activation of hypothyroidism-induced hippocampal cell death.

  6. Ultrasound enhanced activation of peroxydisulfate by activated carbon fiber for decolorization of azo dye.

    Science.gov (United States)

    Huang, Tianyin; Zhang, Ke; Qian, Yajie; Fang, Cong; Chen, Jiabin

    2018-02-20

    Activated carbon fiber (ACF) has become an emerging activator for peroxydisulfate (PDS) to generate sulfate radical (SO 4 •- ). However, the relative low activation efficiency and poor contaminant mineralization limited its widespread application. Herein, ultrasound (US) was introduced to the ACF activated PDS system, and the synergistic effect of US and ACF in PDS activation and the enhancement of contaminant mineralization were investigated. The synergistic effect of US and ACF was observed in the PDS activation to decolorize orange G (OG). The decolorization efficiency increased with increasing ACF loading and US power, and PDS/OG ratio from 1 to 40. The activation energy was determined to be 24.065 kJ/mol. The radical-induced decolorization of OG took place on the surface of ACF, and both SO 4 •- and hydroxyl radical ( • OH) contributed to OG decolorization. The azo bond and naphthalene ring on OG were destructed to other aromatic intermediates and finally mineralized to CO 2 and H 2 O. The introduction of US in the ACF/PDS system significantly enhanced the mineralization of OG. The combination of US and PDS was highly efficient to activate PDS to decolorize azo dyes. Moreover, the introduction of US remarkably improved the contaminant mineralization.

  7. Naphthoquinone Derivative PPE8 Induces Endoplasmic Reticulum Stress in p53 Null H1299 Cells

    Directory of Open Access Journals (Sweden)

    Jin-Cherng Lien

    2015-01-01

    Full Text Available Endoplasmic reticulum (ER plays a key role in synthesizing secretory proteins and sensing signal function in eukaryotic cells. Responding to calcium disturbance, oxidation state change, or pharmacological agents, ER transmembrane protein, inositol-regulating enzyme 1 (IRE1, senses the stress and triggers downstream signals. Glucose-regulated protein 78 (GRP78 dissociates from IRE1 to assist protein folding and guard against cell death. In prolonged ER stress, IRE1 recruits and activates apoptosis signal-regulating kinase 1 (ASK1 as well as downstream JNK for cell death. Naphthoquinones are widespread natural phenolic compounds. Vitamin K3, a derivative of naphthoquinone, inhibits variant tumor cell growth via oxygen uptake and oxygen stress. We synthesized a novel naphthoquinone derivative PPE8 and evaluated capacity to induce ER stress in p53 null H1299 and p53 wild-type A549 cells. In H1299 cells, PPE8 induced ER enlargement, GRP78 expression, and transient IER1 activation. Activated IRE1 recruited ASK1 for downstream JNK phosphorylation. IRE1 knockdown by siRNA attenuated PPE8-induced JNK phosphorylation and cytotoxicity. Prolonged JNK phosphorylation may be involved in PPE8-induced cytotoxicity. Such results did not arise in A549 cells, but p53 knockdown by siRNA restored PPE8-induced GRP78 expression and JNK phosphorylation. We offer a novel compound to induce ER stress and cytotoxicity in p53-deficient cancer cells, presenting an opportunity for treatment.

  8. Gramicidin D enhances the antibacterial activity of fluoride.

    Science.gov (United States)

    Nelson, James W; Zhou, Zhiyuan; Breaker, Ronald R

    2014-07-01

    Fluoride is a toxic anion found in many natural environments. One of the major bacterial defenses against fluoride is the cell envelope, which limits passage of the membrane-impermeant fluoride anion. Accordingly, compounds that enhance the permeability of bacterial membranes to fluoride should also enhance fluoride toxicity. In this study, we demonstrate that the pore-forming antibiotic gramicidin D increases fluoride uptake in Bacillus subtilis and that the antibacterial activity of this compound is potentiated by fluoride. Polymyxin B, another membrane-targeting antibiotic with a different mechanism of action, shows no such improvement. These results, along with previous findings, indicate that certain compounds that destabilize bacterial cell envelopes can enhance the toxicity of fluoride. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Memory-enhancing activity of Anacyclus pyrethrum in albino Wistar rats

    Directory of Open Access Journals (Sweden)

    K Sujith

    2012-08-01

    Full Text Available Objective: To explore the potential effect of ethanolic extract of Anacyclus pyrethrum (A. pyrethrum in memory dysfunction. Methods: Memory impairment was produced by administration of scopolamine (1mg/kg i. p in rats. Passive avoidance paradigms, elevated plus maze and social learning task was used to assess learning and memory. Results: A. pyrethrum extract treated group decreased transfer latency in elevated plus maze model paradigm which is an indicative of cognition improvement. In case of passive avoidance paradigm extract treated group exhibited prounced effect in reversal of scopolamine induced amnesia which was revealed by increase in step down latency. Social learning task also revealed the memory enhancing activity of A. pyrethrum extract. Conclusions: Ethanolic extract of A. pyrethrum has been demonstrated to improve cognitive processes by enhancing memory in different experimental paradigms such as passive avoidance paradigms, elevated plus maze and social learning task when administered orallyBrain cholinesterase level was measured to assess central cholinergic activity. The treatment with drugs, which increase cholinergic neurotransmission, causes an improvement in cognitive deficits. The present study suggest that ethanolic extract of A. pyrethrum increased brain cholinesterase level and hence it possess memory enhancing activity in scopolamine induced amnesia model by enhancing central cholinergic neurotransmission.

  10. Developing design-based STEM education learning activities to enhance students' creative thinking

    Science.gov (United States)

    Pinasa, Siwa; Siripun, Kulpatsorn; Yuenyong, Chokchai

    2018-01-01

    Creative thinking on applying science and mathematics knowledge is required by the future STEM career. The STEM education should be provided for the required skills of future STEM career. This paper aimed to clarify the developing STEM education learning activities to enhance students' creative thinking. The learning activities were developed for Grade 10 students who will study in the subject of independent study (IS) of Khon Kaen Wittayayon School, Khon Kaen, Thailand. The developing STEM education learning activities for enhancing students' creative thinking was developed regarding on 6 steps including (1) providing of understanding of fundamental STEM education concept, (2) generating creative thinking from prototype, (4) revised ideas, (5) engineering ability, and (6) presentation and discussion. The paper will clarify the 18 weeks activities that will be provided based these 6 steps of developing learning activities. Then, these STEM learning activities will be discussed to provide the chance of enhancing students' creative thinking. The paper may have implication for STEM education in school setting.

  11. Anticancer and enhanced antimicrobial activity of biosynthesizd silver nanoparticles against clinical pathogens

    Science.gov (United States)

    Rajeshkumar, Shanmugam; Malarkodi, Chelladurai; Vanaja, Mahendran; Annadurai, Gurusamy

    2016-07-01

    The present investigation shows the biosynthesis of eco-friendly silver nanoparticles using culture supernatant of Enterococcus sp. and study the effect of enhanced antimicrobial activity, anticancer activity against pathogenic bacteria, fungi and cancer cell lines. Silver nanoparticles was synthesized by adding 1 mM silver nitrate into the 100 ml of 24 h freshly prepared culture supernatant of Enterococcus sp. and were characterized by UV-vis spectroscopy, X-ray diffraction (XRD), Transmission Electron Microscope (TEM), Selected Area Diffraction X-Ray (SAED), Energy Dispersive X Ray (EDX) and Fourier Transform Infra red Spectroscopy (FT-IR). The synthesized silver nanoparticles were impregnated with commercial antibiotics for evaluation of enhanced antimicrobial activity. Further these synthesized silver nanoparticles were assessed for its anticancer activity against cancer cell lines. In this study crystalline structured nanoparticles with spherical in the size ranges from 10 to 80 nm and it shows excellent enhanced antimicrobial activity than the commercial antibiotics. The in vitro assay of silver nanoparticles on anticancer have great potential to inhibit the cell viability. Amide linkages and carboxylate groups of proteins from Enterococcus sp. may bind with silver ions and convert into nanoparticles. The activities of commercial antibiotics were enhanced by coating silver nanoparticles shows significant improved antimicrobial activity. Silver nanoparticles have the great potential to inhibit the cell viability of liver cancer cells lines (HepG2) and lung cancer cell lines (A549).

  12. Amygdala activity related to enhanced memory for pleasant and aversive stimuli.

    Science.gov (United States)

    Hamann, S B; Ely, T D; Grafton, S T; Kilts, C D

    1999-03-01

    Pleasant or aversive events are better remembered than neutral events. Emotional enhancement of episodic memory has been linked to the amygdala in animal and neuropsychological studies. Using positron emission tomography, we show that bilateral amygdala activity during memory encoding is correlated with enhanced episodic recognition memory for both pleasant and aversive visual stimuli relative to neutral stimuli, and that this relationship is specific to emotional stimuli. Furthermore, data suggest that the amygdala enhances episodic memory in part through modulation of hippocampal activity. The human amygdala seems to modulate the strength of conscious memory for events according to emotional importance, regardless of whether the emotion is pleasant or aversive.

  13. Metal-chelating active packaging film enhances lysozyme inhibition of Listeria monocytogenes.

    Science.gov (United States)

    Roman, Maxine J; Decker, Eric A; Goddard, Julie M

    2014-07-01

    Several studies have demonstrated that metal chelators enhance the antimicrobial activity of lysozyme. This study examined the effect of metal-chelating active packaging film on the antimicrobial activity of lysozyme against Listeria monocytogenes. Polypropylene films were surface modified by photoinitiated graft polymerization of acrylic acid (PP-g-PAA) from the food contact surface of the films to impart chelating activity based on electrostatic interactions. PP-g-PAA exhibited a carboxylic acid density of 113 ± 5.4 nmol cm(-2) and an iron chelating activity of 53.7 ± 9.8 nmol cm(-2). The antimicrobial interaction of lysozyme and PP-g-PAA depended on growth media composition. PP-g-PAA hindered lysozyme activity at low ionic strength (2.48-log increase at 64.4 mM total ionic strength) and enhanced lysozyme activity at moderate ionic strength (5.22-log reduction at 120 mM total ionic strength). These data support the hypothesis that at neutral pH, synergy between carboxylate metal-chelating films (pKa(bulk) 6.45) and lysozyme (pI 11.35) is optimal in solutions of moderate to high ionic strength to minimize undesirable charge interactions, such as lysozyme absorption onto film. These findings suggest that active packaging, which chelates metal ions based on ligand-specific interactions, in contrast to electrostatic interactions, may improve antimicrobial synergy. This work demonstrates the potential application of metal-chelating active packaging films to enhance the antimicrobial activity of membrane-disrupting antimicrobials, such as lysozyme.

  14. The Elav-like protein HuR exerts translational control of viral internal ribosome entry sites

    International Nuclear Information System (INIS)

    Rivas-Aravena, Andrea; Ramdohr, Pablo; Vallejos, Maricarmen; Valiente-Echeverria, Fernando; Dormoy-Raclet, Virginie; Rodriguez, Felipe; Pino, Karla; Holzmann, Cristian; Huidobro-Toro, J. Pablo; Gallouzi, Imed-Eddine; Lopez-Lastra, Marcelo

    2009-01-01

    The human embryonic-lethal abnormal vision (ELAV)-like protein, HuR, has been recently found to be involved in the regulation of protein synthesis. In this study we show that HuR participates in the translational control of the HIV-1 and HCV IRES elements. HuR functions as a repressor of HIV-1 IRES activity and acts as an activator of the HCV IRES. The effect of HuR was evaluated in three independent experimental systems, rabbit reticulocyte lysate, HeLa cells, and Xenopus laevis oocytes, using both overexpression and knockdown approaches. Furthermore, results suggest that HuR mediated regulation of HIV-1 and HCV IRESes does not require direct binding of the protein to the RNA nor does it need the nuclear translocation of the IRES-containing RNAs. Finally, we show that HuR has a negative impact on post-integration steps of the HIV-1 replication cycle. Thus, our observations yield novel insights into the role of HuR in the post-transcriptional regulation of HCV and HIV-1 gene expression.

  15. Active and inactive enhancers co-operate to exert localized and long-range control of gene regulation

    Science.gov (United States)

    Proudhon, Charlotte; Snetkova, Valentina; Raviram, Ramya; Lobry, Camille; Badri, Sana; Jiang, Tingting; Hao, Bingtao; Trimarchi, Thomas; Kluger, Yuval; Aifantis, Iannis; Bonneau, Richard; Skok, Jane A

    2016-01-01

    V(D)J recombination relies on the presence of proximal enhancers that activate the antigen receptor (AgR) loci in a lineage and stage specific manner. Unexpectedly we find that both active and inactive AgR enhancers co-operate to disseminate their effects in a localized and long-range manner. Here we demonstrate the importance of short-range contacts between active enhancers that constitute an Igk super-enhancer in B cells. Deletion of one element reduces the interaction frequency between other enhancers in the hub, which compromises the transcriptional output of each component. We further establish that in T cells long-range contact and co-operation between the inactive Igk enhancer, MiEκ and the active Tcrb enhancer, Eβ, alters enrichment of CBFβ binding in a manner that impacts Tcrb recombination. These findings underline the complexities of enhancer regulation and point to a role for localized and long-range enhancer-sharing between active and inactive elements in lineage and stage specific control. PMID:27239026

  16. Next-generation proteasome inhibitor oprozomib synergizes with modulators of the unfolded protein response to suppress hepatocellular carcinoma.

    Science.gov (United States)

    Vandewynckel, Yves-Paul; Coucke, Céline; Laukens, Debby; Devisscher, Lindsey; Paridaens, Annelies; Bogaerts, Eliene; Vandierendonck, Astrid; Raevens, Sarah; Verhelst, Xavier; Van Steenkiste, Christophe; Libbrecht, Louis; Geerts, Anja; Van Vlierberghe, Hans

    2016-06-07

    Hepatocellular carcinoma (HCC) responds poorly to conventional systemic therapies. The first-in-class proteasome inhibitor bortezomib has been approved in clinical use for hematologic malignancies and has shown modest activity in solid tumors, including HCC. However, a considerable proportion of patients fail to respond and experience important adverse events. Recently, the next-generation orally bioavailable irreversible proteasome inhibitor oprozomib was developed. Here, we assessed the efficacy of oprozomib and its effects on the unfolded protein response (UPR), a signaling cascade activated through the ATF6, PERK and IRE1 pathways by accumulation of unfolded proteins in the endoplasmic reticulum, in HCC. The effects of oprozomib and the role of the UPR were evaluated in HCC cell lines and in diethylnitrosamine-induced and xenograft mouse models for HCC. Oprozomib dose-dependently reduced the viability and proliferation of human HCC cells. Unexpectedly, oprozomib-treated cells displayed diminished cytoprotective ATF6-mediated signal transduction as well as unaltered PERK and IRE1 signaling. However, oprozomib increased pro-apoptotic UPR-mediated protein levels by prolonging their half-life, implying that the proteasome acts as a negative UPR regulator. Supplementary boosting of UPR activity synergistically improved the sensitivity to oprozomib via the PERK pathway. Oral oprozomib displayed significant antitumor effects in the orthotopic and xenograft models for HCC, and importantly, combining oprozomib with different UPR activators enhanced the antitumor efficacy by stimulating UPR-induced apoptosis without cumulative toxicity. In conclusion, next-generation proteasome inhibition by oprozomib results in dysregulated UPR activation in HCC. This finding can be exploited to enhance the antitumor efficacy by combining oprozomib with clinically applicable UPR activators.

  17. Enhanced casein kinase II activity in human tumour cell cultures

    DEFF Research Database (Denmark)

    Prowald, K; Fischer, H; Issinger, O G

    1984-01-01

    Casein kinase II (CKII) activity is enhanced as much as 2-3 fold in established and 4-5-fold in transformed human cell lines when compared to that of fibroblasts and primary human tumour cell cultures where CKII activity never exceeded a basic level. The high activity of CKII in transformed cells...

  18. 6-Shogaol induces apoptosis in human hepatocellular carcinoma cells and exhibits anti-tumor activity in vivo through endoplasmic reticulum stress.

    Directory of Open Access Journals (Sweden)

    Rong Hu

    Full Text Available 6-Shogaol is an active compound isolated from Ginger (Zingiber officinale Rosc. In this work, we demonstrated that 6-shogaol induces apoptosis in human hepatocellular carcinoma cells in relation to caspase activation and endoplasmic reticulum (ER stress signaling. Proteomic analysis revealed that ER stress was accompanied by 6-shogaol-induced apoptosis in hepatocellular carcinoma cells. 6-shogaol affected the ER stress signaling by regulating unfolded protein response (UPR sensor PERK and its downstream target eIF2α. However, the effect on the other two UPR sensors IRE1 and ATF6 was not obvious. In prolonged ER stress, 6-shogaol inhibited the phosphorylation of eIF2α and triggered apoptosis in SMMC-7721 cells. Salubrinal, an activator of the PERK/eIF2α pathway, strikingly enhanced the phosphorylation of eIF2α in SMMC-7721 cells with no toxicity. However, combined treatment with 6-shogaol and salubrinal resulted in significantly increase of apoptosis and dephosphorylation of eIF2α. Overexpression of eIF2α prevented 6-shogaol-mediated apoptosis in SMMC-7721 cells, whereas inhibition of eIF2α by small interfering RNA markedly enhanced 6-shogaol-mediated cell death. Furthermore, 6-shogaol-mediated inhibition of tumor growth of mouse SMMC-7721 xenograft was associated with induction of apoptosis, activation of caspase-3, and inactivation of eIF2α. Altogether our results indicate that the PERK/eIF2α pathway plays an important role in 6-shogaol-mediated ER stress and apoptosis in SMMC-7721 cells in vitro and in vivo.

  19. Divergent antiviral effects of bioflavonoids on the hepatitis C virus life cycle

    Energy Technology Data Exchange (ETDEWEB)

    Khachatoorian, Ronik, E-mail: RnKhch@ucla.edu [Molecular Biology Interdepartmental Ph.D. Program (MBIDP), Molecular Biology Institute, David Geffen School of Medicine at University of California, Los Angeles, California, CA (United States); Molecular Biology Institute, David Geffen School of Medicine at University of California, Los Angeles, California, CA (United States); Arumugaswami, Vaithilingaraja, E-mail: VArumugaswami@mednet.ucla.edu [Department of Molecular and Medical Pharmacology, David Geffen School of Medicine at University of California, Los Angeles, California, CA (United States); Department of Surgery, Regenerative Medicine Institute at Cedars-Sinai Medical Center, Los Angeles, California, CA (United States); Raychaudhuri, Santanu, E-mail: SRaychau@ucla.edu [Department of Microbiology, Immunology, and Molecular Genetics, David Geffen School of Medicine at University of California, Los Angeles, California, CA (United States); Yeh, George K., E-mail: GgYeh@ucla.edu [Molecular Biology Interdepartmental Ph.D. Program (MBIDP), Molecular Biology Institute, David Geffen School of Medicine at University of California, Los Angeles, California, CA (United States); Molecular Biology Institute, David Geffen School of Medicine at University of California, Los Angeles, California, CA (United States); Maloney, Eden M., E-mail: EMaloney@ucla.edu [Department of Molecular, Cell, and Developmental Biology, University of California, Los Angeles, California, CA (United States); Wang, Julie, E-mail: JulieW1521@ucla.edu [Department of Microbiology, Immunology, and Molecular Genetics, David Geffen School of Medicine at University of California, Los Angeles, California, CA (United States); and others

    2012-11-25

    We have previously demonstrated that quercetin, a bioflavonoid, blocks hepatitis C virus (HCV) proliferation by inhibiting NS5A-driven internal ribosomal entry site (IRES)-mediated translation of the viral genome. Here, we investigate the mechanisms of antiviral activity of quercetin and six additional bioflavonoids. We demonstrate that catechin, naringenin, and quercetin possess significant antiviral activity, with no associated cytotoxicity. Infectious virion secretion was not significantly altered by these bioflavonoids. Catechin and naringenin demonstrated stronger inhibition of infectious virion assembly compared to quercetin. Quercetin markedly blocked viral translation whereas catechin and naringenin demonstrated mild activity. Similarly quercetin completely blocked NS5A-augmented IRES-mediated translation in an IRES reporter assay, whereas catechin and naringenin had only a mild effect. Moreover, quercetin differentially inhibited HSP70 induction compared to catechin and naringenin. Thus, the antiviral activity of these bioflavonoids is mediated through different mechanisms. Therefore combination of these bioflavonoids may act synergistically against HCV.

  20. Enhanced natural radiation exposure enhanced by human activity: the largest contributor to the Chinese population dose

    International Nuclear Information System (INIS)

    Pan Ziqiang; Liu Yanyang

    2011-01-01

    For the radiation exposure caused by human activities, the enhanced natural radiation exposure is the largest contributor to Chinese population dose. This problem has attracted social attention in recent years. Efforts have been made in several fields, such as radon indoors and in workplace, environmental problems associated with NORMs, occupational radiation hazards of non-uranium mine, and radiation dose evaluation for energy chain, but there are still many problems to be solved. In order to protect the health of workers and the public, while ensuring industrial production and economic development, it is also necessary to continue to strengthen research in all aspects above mentioned, and gradually promote the control of natural radiation exposure enhanced by human activities. (authors)

  1. Why we should not routinely apply irreversible electroporation as an alternative curative treatment modality for localized prostate cancer at this stage.

    Science.gov (United States)

    Wendler, J J; Ganzer, R; Hadaschik, B; Blana, A; Henkel, T; Köhrmann, K U; Machtens, S; Roosen, A; Salomon, G; Sentker, L; Witzsch, U; Schlemmer, H P; Baumunk, D; Köllermann, J; Schostak, M; Liehr, U B

    2017-01-01

    Irreversible electroporation (IRE), a new tissue ablation procedure available since 2007, could meet the requirements for ideal focal therapy of prostate cancer with its postulated features, especially the absence of a thermal ablation effect. Thus far, there is not enough evidence of its effectiveness or adverse effects to justify its use as a definitive treatment option for localized prostate cancer. Moreover, neither optimal nor individual treatment parameters nor uniform endpoints have been defined thus far. No advantages over established treatment procedures have as yet been demonstrated. Nevertheless, IRE is now being increasingly applied for primary prostate cancer therapy outside clinical trials, not least through active advertising in the lay press. This review reflects the previous relevant literature on IRE of the prostate or prostate cancer and shows why we should not adopt IRE as a routine treatment modality at this stage.

  2. Resonance Raman Optical Activity and Surface Enhanced Resonance Raman Optical Activity analysis of Cytochrome C

    DEFF Research Database (Denmark)

    Johannessen, Christian; Abdali, Salim; White, Peter C.

    2007-01-01

    High quality Resonance Raman (RR) and resonance Raman Optical Activity (ROA) spectra of cytochrome c were obtained in order to perform full assignment of spectral features of the resonance ROA spectrum. The resonance ROA spectrum of cytochrome c revealed a distinct spectral signature pattern due...... to resonance enhanced skeletal porphyrin vibrations, more pronounced than any contribution from the protein back-bone. Combining the intrinsic resonance enhancement of cytochrome c with surface plasmon enhancement by colloidal silver particles, the Surface Enhanced Resonance Raman Scattering (SERRS) and Chiral...... Enhanced Raman Spectroscopy (ChERS) spectra of the protein were successfully obtained at very low concentration (as low as 1 µM). The assignment of spectral features was based on the information obtained from the RR and resonance ROA spectra. Excellent agreement between RR and SERRS spectra is reported...

  3. High-affinity interaction of hnRNP A1 with conserved RNA structural elements is required for translation and replication of enterovirus 71.

    Science.gov (United States)

    Levengood, Jeffrey D; Tolbert, Michele; Li, Mei-Ling; Tolbert, Blanton S

    2013-07-01

    Human Enterovirus 71 (EV71) is an emerging pathogen of infectious disease and a serious threat to public health. Currently, there are no antivirals or vaccines to slow down or prevent EV71 infections, thus underscoring the urgency to better understand mechanisms of host-enterovirus interactions. EV71 uses a type I internal ribosome entry site (IRES) to recruit the 40S ribosomal subunit via a pathway that requires the cytoplasmic localization of hnRNP A1, which acts as an IRES trans-activating factor. The mechanism of how hnRNP A1 trans activates EV71 RNA translation is unknown, however. Here, we report that the UP1 domain of hnRNP A1 interacts specifically with stem loop II (SLII) of the IRES, via a thermodynamically well-defined biphasic transition that involves conserved bulge 5'-AYAGY-3' and hairpin 5'-RY(U/A)CCA-3' loops. Calorimetric titrations of wild-type and mutant SLII constructs reveal these structural elements are essential to form a high-affinity UP1-SLII complex. Mutations that alter the bulge and hairpin primary or secondary structures abrogate the biphasic transition and destabilize the complex. Notably, mutations within the bulge that destabilize the complex correlate with a large reduction in IRES-dependent translational activity and impair EV71 replication. Taken together, this study shows that a conserved SLII structure is necessary to form a functional hnRNP A1-IRES complex, suggesting that small molecules that target this stem loop may have novel antiviral properties.

  4. Educating Students for a Lifetime of Physical Activity: Enhancing Mindfulness, Motivation, and Meaning

    Science.gov (United States)

    Ennis, Catherine D.

    2017-01-01

    For many years, pedagogical scholars and physical education (PE) teachers have worked to enhance effective teaching and learning environments. Yet for some children, youth, and young adults, many of the benefits associated with a physically active lifestyle remain elusive. Enhancing programming and performance to meet physical activity goals may…

  5. Activity enhancement of ligninolytic enzymes of Trametes versicolor ...

    African Journals Online (AJOL)

    Suspended cultures of white-rot fungus, Trametes versicolor, supplemented with bagasse powder showed a concentration dependent enhancement in the ligninolytic enzymes activity in liquid shake cultures. 2% (w/v) bagasse powder improved greater stability to the enzymes. The optimum pH is 3.5 and the optimum ...

  6. Integration of Bass Enhancement and Active Noise Control System in Automobile Cabin

    Directory of Open Access Journals (Sweden)

    Liang Wang

    2008-01-01

    Full Text Available With the advancement of digital signal processing technologies, consumers are more concerned with the quality of multimedia entertainment in automobiles. In order to meet this demand, an audio enhancement system is needed to improve bass reproduction and cancel engine noise in the cabins. This paper presents an integrated active noise control system that is based on frequency-sampling filters to track and extract the bass information from the audio signal, and a multifrequency active noise equalizer to tune the low-frequency engine harmonics to enhance the bass reproduction. In the noise cancellation mode, a maximum of 3 dB bass enhancement can be achieved with significant noise suppression, while higher bass enhancement can be achieved in the bass enhance mode. The results show that the proposed system is effective for solving both the bass audio reproduction and the noise control problems in automobile cabins.

  7. ChIP-seq Mapping of Distant-Acting Enhancers and Their In Vivo Activities

    Energy Technology Data Exchange (ETDEWEB)

    Visel, Axel; Pennacchio, Len A.

    2011-06-01

    The genomic location and function of most distant-acting transcriptional enhancers in the human genome remains unknown We performed ChIP-seq for various transcriptional coactivator proteins (such as p300) directly from different embryonic mouse tissues, identifying thousands of binding sitesTransgenic mouse experiments show that p300 and other co-activator peaks are highly predictive of genomic location AND tissue-specific activity patterns of distant-acting enhancersMost enhancers are active only in one or very few tissues Genomic location of tissue-specific p300 peaks correlates with tissue-specific expression of nearby genes Most binding sites are conserved, but the global degree of conservation varies between tissues

  8. Brucella suis vaccine strain 2 induces endoplasmic reticulum stress that affects intracellular replication in goat trophoblast cells in vitro

    Directory of Open Access Journals (Sweden)

    Xiangguo eWang

    2016-02-01

    Full Text Available Brucella has been reported to impair placental trophoblasts, a cellular target where Brucella efficiently replicates in association with the endoplasmic reticulum (ER, and ultimately trigger abortion in pregnant animals. However, the precise effects of Brucella on trophoblast cells remain unclear. Here, we describe the infection and replication of Brucella suis vaccine strain 2 (B.suis.S2 in goat trophoblast cells (GTCs and the cellular and molecular responses induced in vitro. Our studies demonstrated that B.suis.S2 was able to infect and proliferate to high titers, hamper the proliferation of GTCs and induce apoptosis due to ER stress. Tunicamycin (Tm, a pharmacological chaperone that strongly mounts ER stress-induced apoptosis, inhibited B.suis.S2 replication in GTCs. In addition, 4 phenyl butyric acid (4-PBA, a pharmacological chaperone that alleviates ER stress-induced apoptosis, significantly enhanced B.suis.S2 replication in GTCs. The Unfolded Protein Response (UPR chaperone molecule GRP78 also promoted B.suis.S2 proliferation in GTCs by inhibiting ER stress-induced apoptosis. We also discovered that the IRE1 pathway, but not the PERK or ATF6 pathway, was activated in the process. However, decreasing the expression of phosphoIRE1α and IRE1α proteins with Irestatin 9389 (IRE1 antagonist in GTCs did not affect the proliferation of B.suis.S2. Although GTC implantation was not affected upon B.suis.S2 infection, progesterone secretion was suppressed, and prolactin and estrogen secretion increased; these effects were accompanied by changes in the expression of genes encoding key steroidogenic enzymes. This study systematically explored the mechanisms of abortion in Brucella infection from the viewpoint of pathogen invasion, ER stress and reproductive endocrinology. Our findings may provide new insight for understanding the mechanisms involved in goat abortions caused by Brucella infection.

  9. Psychosocial Practices that Enhance Cognitive Activity in Dementia

    Directory of Open Access Journals (Sweden)

    Neslihan Lok

    2014-09-01

    Full Text Available The daily lives of individuals with dementia, cognitive aspects need to be strengthened in order to maintain the quality. For this reason, dementia, cognitive, psycho-social applications there is a need to increase activity. Dementia drug treatment interventions used as an aid to increase cognitive activity. These interventions, behavior, emotion, perception and stimulation-oriented approaches can be classified into four groups. Dementia cognitive enhancer activity and an older group, this intervention and dissemination practices for selecting the most appropriate method to be applied. All psychosocial practices to increase cognitive activity psychiatrist, psychiatric nurse specialists, psychologists, social workers, occupational therapists can with the condition to study the relevant therapy. [Psikiyatride Guncel Yaklasimlar - Current Approaches in Psychiatry 2014; 6(3.000: 210-216

  10. Telmisartan enhances mitochondrial activity and alters cellular functions in human coronary artery endothelial cells via AMP-activated protein kinase pathway.

    Science.gov (United States)

    Kurokawa, Hirofumi; Sugiyama, Seigo; Nozaki, Toshimitsu; Sugamura, Koichi; Toyama, Kensuke; Matsubara, Junichi; Fujisue, Koichiro; Ohba, Keisuke; Maeda, Hirofumi; Konishi, Masaaki; Akiyama, Eiichi; Sumida, Hitoshi; Izumiya, Yasuhiro; Yasuda, Osamu; Kim-Mitsuyama, Shokei; Ogawa, Hisao

    2015-04-01

    Mitochondrial dysfunction plays an important role in cellular senescence and impaired function of vascular endothelium, resulted in cardiovascular diseases. Telmisartan is a unique angiotensin II type I receptor blocker that has been shown to prevent cardiovascular events in high risk patients. AMP-activated protein kinase (AMPK) plays a critical role in mitochondrial biogenesis and endothelial function. This study assessed whether telmisartan enhances mitochondrial function and alters cellular functions via AMPK in human coronary artery endothelial cells (HCAECs). In cultured HCAECs, telmisartan significantly enhanced mitochondrial activity assessed by mitochondrial reductase activity and intracellular ATP production and increased the expression of mitochondria related genes. Telmisartan prevented cellular senescence and exhibited the anti-apoptotic and pro-angiogenic properties. The expression of genes related anti-oxidant and pro-angiogenic properties were increased by telmisartan. Telmisartan increased endothelial NO synthase and AMPK phosphorylation. Peroxisome proliferator-activated receptor gamma signaling was not involved in telmisartan-induced improvement of mitochondrial function. All of these effects were abolished by inhibition of AMPK. Telmisartan enhanced mitochondrial activity and exhibited anti-senescence effects and improving endothelial function through AMPK in HCAECs. Telmisartan could provide beneficial effects on vascular diseases via enhancement of mitochondrial activity and modulating endothelial function through AMPK activation. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  11. Involvement of the iron regulatory protein from Eisenia andrei earthworms in the regulation of cellular iron homeostasis.

    Directory of Open Access Journals (Sweden)

    Petra Procházková

    Full Text Available Iron homeostasis in cells is regulated by iron regulatory proteins (IRPs that exist in different organisms. IRPs are cytosolic proteins that bind to iron-responsive elements (IREs of the 5'- or 3'-untranslated regions (UTR of mRNAs that encode many proteins involved in iron metabolism. In this study, we have cloned and described a new regulatory protein belonging to the family of IRPs from the earthworm Eisenia andrei (EaIRP. The earthworm IRE site in 5'-UTR of ferritin mRNA most likely folds into a secondary structure that differs from the conventional IRE structures of ferritin due to the absence of a typically unpaired cytosine that participates in protein binding. Prepared recombinant EaIRP and proteins from mammalian liver extracts are able to bind both mammalian and Eisenia IRE structures of ferritin mRNA, although the affinity of the rEaIRP/Eisenia IRE structure is rather low. This result suggests the possible contribution of a conventional IRE structure. When IRP is supplemented with a Fe-S cluster, it can function as a cytosolic aconitase. Cellular cytosolic and mitochondrial fractions, as well as recombinant EaIRP, exhibit aconitase activity that can be abolished by the action of oxygen radicals. The highest expression of EaIRP was detected in parts of the digestive tract. We can assume that earthworms may possess an IRE/IRP regulatory network as a potential mechanism for maintaining cellular iron homeostasis, although the aconitase function of EaIRP is most likely more relevant.

  12. Involvement of the Iron Regulatory Protein from Eisenia andrei Earthworms in the Regulation of Cellular Iron Homeostasis

    Science.gov (United States)

    Procházková, Petra; Škanta, František; Roubalová, Radka; Šilerová, Marcela; Dvořák, Jiří; Bilej, Martin

    2014-01-01

    Iron homeostasis in cells is regulated by iron regulatory proteins (IRPs) that exist in different organisms. IRPs are cytosolic proteins that bind to iron-responsive elements (IREs) of the 5′- or 3′-untranslated regions (UTR) of mRNAs that encode many proteins involved in iron metabolism. In this study, we have cloned and described a new regulatory protein belonging to the family of IRPs from the earthworm Eisenia andrei (EaIRP). The earthworm IRE site in 5′-UTR of ferritin mRNA most likely folds into a secondary structure that differs from the conventional IRE structures of ferritin due to the absence of a typically unpaired cytosine that participates in protein binding. Prepared recombinant EaIRP and proteins from mammalian liver extracts are able to bind both mammalian and Eisenia IRE structures of ferritin mRNA, although the affinity of the rEaIRP/Eisenia IRE structure is rather low. This result suggests the possible contribution of a conventional IRE structure. When IRP is supplemented with a Fe-S cluster, it can function as a cytosolic aconitase. Cellular cytosolic and mitochondrial fractions, as well as recombinant EaIRP, exhibit aconitase activity that can be abolished by the action of oxygen radicals. The highest expression of EaIRP was detected in parts of the digestive tract. We can assume that earthworms may possess an IRE/IRP regulatory network as a potential mechanism for maintaining cellular iron homeostasis, although the aconitase function of EaIRP is most likely more relevant. PMID:25279857

  13. Unfolded protein response is required for Aspergillus oryzae growth under conditions inducing secretory hydrolytic enzyme production.

    Science.gov (United States)

    Tanaka, Mizuki; Shintani, Takahiro; Gomi, Katsuya

    2015-12-01

    Unfolded protein response (UPR) is an intracellular signaling pathway for adaptation to endoplasmic reticulum (ER) stress. In yeast UPR, Ire1 cleaves the unconventional intron of HAC1 mRNA, and the functional Hac1 protein translated from the spliced HAC1 mRNA induces the expression of ER chaperone genes and ER-associated degradation genes for the refolding or degradation of unfolded proteins. In this study, we constructed an ireA (IRE1 ortholog) conditionally expressing strain of Aspergillus oryzae, a filamentous fungus producing a large amount of amylolytic enzymes, and examined the contribution of UPR to ER stress adaptation under physiological conditions. Repression of ireA completely blocked A. oryzae growth under conditions inducing the production of hydrolytic enzymes, such as amylases and proteases. This growth defect was restored by the introduction of unconventional intronless hacA (hacA-i). Furthermore, UPR was observed to be induced by amylolytic gene expression, and the disruption of the transcriptional activator for amylolytic genes resulted in partial growth restoration of the ireA-repressing strain. In addition, a homokaryotic ireA disruption mutant was successfully generated using the strain harboring hacA-i as a parental host. These results indicated that UPR is required for A. oryzae growth to alleviate ER stress induced by excessive production of hydrolytic enzymes. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. Activation of the polyomavirus enhancer by a murine activator protein 1 (AP1) homolog and two contiguous proteins.

    OpenAIRE

    Martin, M E; Piette, J; Yaniv, M; Tang, W J; Folk, W R

    1988-01-01

    The polyomavirus enhancer is composed of multiple DNA sequence elements serving as binding sites for proteins present in mouse nuclear extracts that activate transcription and DNA replication. We have identified three such proteins and their binding sites and correlate them with enhancer function. Mutation of nucleotide (nt) 5140 in the enhancer alters the binding site (TGACTAA, nt 5139-5145) for polyomavirus enhancer A binding protein 1 (PEA1), a murine homolog of the human transcription fac...

  15. Passivity enhancement by series LC filtered active damper with zero current reference

    DEFF Research Database (Denmark)

    Bai, Haofeng; Wang, Xiongfei; Blaabjerg, Frede

    2016-01-01

    can be improved by enhancing the passivity of the total admittance seen by the grid, which allows for a zero current reference and a much simpler current controller for the active damper. To show the performance of the active damper with zero reference, this paper first carries out the impedance based...... stability analysis of grid converters in the weak grid. Based on the impedance model of the series LC filtered active damper, the real part of its output admittance is investigated and shown to be able to enhance the passivity of the admittance of the converters seen by the grid. Finally, simulation...

  16. CT-guided Irreversible Electroporation in an Acute Porcine Liver Model: Effect of Previous Transarterial Iodized Oil Tissue Marking on Technical Parameters, 3D Computed Tomographic Rendering of the Electroporation Zone, and Histopathology

    International Nuclear Information System (INIS)

    Sommer, C. M.; Fritz, S.; Vollherbst, D.; Zelzer, S.; Wachter, M. F.; Bellemann, N.; Gockner, T.; Mokry, T.; Schmitz, A.; Aulmann, S.; Stampfl, U.; Pereira, P.; Kauczor, H. U.; Werner, J.; Radeleff, B. A.

    2015-01-01

    PurposeTo evaluate the effect of previous transarterial iodized oil tissue marking (ITM) on technical parameters, three-dimensional (3D) computed tomographic (CT) rendering of the electroporation zone, and histopathology after CT-guided irreversible electroporation (IRE) in an acute porcine liver model as a potential strategy to improve IRE performance.MethodsAfter Ethics Committee approval was obtained, in five landrace pigs, two IREs of the right and left liver (RL and LL) were performed under CT guidance with identical electroporation parameters. Before IRE, transarterial marking of the LL was performed with iodized oil. Nonenhanced and contrast-enhanced CT examinations followed. One hour after IRE, animals were killed and livers collected. Mean resulting voltage and amperage during IRE were assessed. For 3D CT rendering of the electroporation zone, parameters for size and shape were analyzed. Quantitative data were compared by the Mann–Whitney test. Histopathological differences were assessed.ResultsMean resulting voltage and amperage were 2,545.3 ± 66.0 V and 26.1 ± 1.8 A for RL, and 2,537.3 ± 69.0 V and 27.7 ± 1.8 A for LL without significant differences. Short axis, volume, and sphericity index were 16.5 ± 4.4 mm, 8.6 ± 3.2 cm 3 , and 1.7 ± 0.3 for RL, and 18.2 ± 3.4 mm, 9.8 ± 3.8 cm 3 , and 1.7 ± 0.3 for LL without significant differences. For RL and LL, the electroporation zone consisted of severely widened hepatic sinusoids containing erythrocytes and showed homogeneous apoptosis. For LL, iodized oil could be detected in the center and at the rim of the electroporation zone.ConclusionThere is no adverse effect of previous ITM on technical parameters, 3D CT rendering of the electroporation zone, and histopathology after CT-guided IRE of the liver

  17. CT-guided Irreversible Electroporation in an Acute Porcine Liver Model: Effect of Previous Transarterial Iodized Oil Tissue Marking on Technical Parameters, 3D Computed Tomographic Rendering of the Electroporation Zone, and Histopathology

    Energy Technology Data Exchange (ETDEWEB)

    Sommer, C. M., E-mail: christof.sommer@med.uni-heidelberg.de [University Hospital Heidelberg, Department of Diagnostic and Interventional Radiology (Germany); Fritz, S., E-mail: stefan.fritz@med.uni-heidelberg.de [University Hospital Heidelberg, Department of General Visceral and Transplantation Surgery (Germany); Vollherbst, D., E-mail: dominikvollherbst@web.de [University Hospital Heidelberg, Department of Diagnostic and Interventional Radiology (Germany); Zelzer, S., E-mail: s.zelzer@dkfz-heidelberg.de [German Cancer Research Center (dkfz), Medical and Biological Informatics (Germany); Wachter, M. F., E-mail: fredericwachter@googlemail.com; Bellemann, N., E-mail: nadine.bellemann@med.uni-heidelberg.de; Gockner, T., E-mail: theresa.gockner@med.uni-heidelberg.de; Mokry, T., E-mail: theresa.mokry@med.uni-heidelberg.de; Schmitz, A., E-mail: anne.schmitz@med.uni-heidelberg.de [University Hospital Heidelberg, Department of Diagnostic and Interventional Radiology (Germany); Aulmann, S., E-mail: sebastian.aulmann@mail.com [University Hospital Heidelberg, Department of General Pathology (Germany); Stampfl, U., E-mail: ulrike.stampfl@med.uni-heidelberg.de [University Hospital Heidelberg, Department of Diagnostic and Interventional Radiology (Germany); Pereira, P., E-mail: philippe.pereira@slk-kliniken.de [SLK Kliniken Heilbronn GmbH, Clinic for Radiology, Minimally-invasive Therapies and Nuclear Medicine (Germany); Kauczor, H. U., E-mail: hu.kauczor@med.uni-heidelberg.de [University Hospital Heidelberg, Department of Diagnostic and Interventional Radiology (Germany); Werner, J., E-mail: jens.werner@med.uni-heidelberg.de [University Hospital Heidelberg, Department of General Visceral and Transplantation Surgery (Germany); Radeleff, B. A., E-mail: boris.radeleff@med.uni-heidelberg.de [University Hospital Heidelberg, Department of Diagnostic and Interventional Radiology (Germany)

    2015-02-15

    PurposeTo evaluate the effect of previous transarterial iodized oil tissue marking (ITM) on technical parameters, three-dimensional (3D) computed tomographic (CT) rendering of the electroporation zone, and histopathology after CT-guided irreversible electroporation (IRE) in an acute porcine liver model as a potential strategy to improve IRE performance.MethodsAfter Ethics Committee approval was obtained, in five landrace pigs, two IREs of the right and left liver (RL and LL) were performed under CT guidance with identical electroporation parameters. Before IRE, transarterial marking of the LL was performed with iodized oil. Nonenhanced and contrast-enhanced CT examinations followed. One hour after IRE, animals were killed and livers collected. Mean resulting voltage and amperage during IRE were assessed. For 3D CT rendering of the electroporation zone, parameters for size and shape were analyzed. Quantitative data were compared by the Mann–Whitney test. Histopathological differences were assessed.ResultsMean resulting voltage and amperage were 2,545.3 ± 66.0 V and 26.1 ± 1.8 A for RL, and 2,537.3 ± 69.0 V and 27.7 ± 1.8 A for LL without significant differences. Short axis, volume, and sphericity index were 16.5 ± 4.4 mm, 8.6 ± 3.2 cm{sup 3}, and 1.7 ± 0.3 for RL, and 18.2 ± 3.4 mm, 9.8 ± 3.8 cm{sup 3}, and 1.7 ± 0.3 for LL without significant differences. For RL and LL, the electroporation zone consisted of severely widened hepatic sinusoids containing erythrocytes and showed homogeneous apoptosis. For LL, iodized oil could be detected in the center and at the rim of the electroporation zone.ConclusionThere is no adverse effect of previous ITM on technical parameters, 3D CT rendering of the electroporation zone, and histopathology after CT-guided IRE of the liver.

  18. Inhibition of autophagy enhances the cytotoxic effect of PA-MSHA in breast cancer

    International Nuclear Information System (INIS)

    Xu, Wen-Huan; Liu, Zhe-Bin; Hou, Yi-Feng; Hong, Qi; Hu, Da-Li; Shao, Zhi-Ming

    2014-01-01

    PA-MSHA, a genetically engineered Pseudomonas aeruginosa (PA) strain, is currently under investigation as a new anti-cancer drug. It can induce cell cycle arrest and apoptosis in different human cancer cells, including hormone receptor negative breast cancer cells. However, the underlying mechanism of tumor lethality mediated by PA-MSHA remains to be fully investigated. The effect of PA-MSHA on human hormone receptor negative breast cancer cells was analyzed by morphological measurement, western blot, cell proliferation assay and mouse xenograft model. PA-MSHA was found to induce endoplasmic reticulum (ER) stress in breast cancer cell lines through the IRE1 signaling pathway. Inhibiting autophagy potentiated the cytotoxic effect of PA-MSHA while treating breast cancer cell lines. In mouse xenograft model, PA-MSHA produced more pronounced tumor suppression in mice inoculated with IRE1 gene knockdown. MDA-MB-231HM cells. These findings demonstrated inhibiting autophagy together with PA-MSHA might be a promising therapeutic strategy in treating hormone receptor negative breast cancer cells

  19. Enhanced supercapacitance of activated vertical graphene nanosheets in hybrid electrolyte

    Science.gov (United States)

    Ghosh, Subrata; Sahoo, Gopinath; Polaki, S. R.; Krishna, Nanda Gopala; Kamruddin, M.; Mathews, Tom

    2017-12-01

    Supercapacitors are becoming the workhorse for emerging energy storage applications due to their higher power density and superior cycle life compared to conventional batteries. The performance of supercapacitors depends on the electrode material, type of electrolyte, and interaction between them. Owing to the beneficial interconnected porous structure with multiple conducting channels, vertical graphene nanosheets (VGN) have proved to be leading supercapacitor electrode materials. Herein, we demonstrate a novel approach based on the combination of surface activation and a new organo-aqueous hybrid electrolyte, tetraethylammonium tetrafluoroborate in H2SO4, to achieve significant enhancement in supercapacitor performance of VGN. As-synthesized VGN exhibits an excellent supercapacitance of 0.64 mF/cm2 in H2SO4. However, identification of a novel electrolyte for performance enhancement is the subject of current research. The present manuscript demonstrates the potential of the hybrid electrolyte in enhancing the areal capacitance (1.99 mF/cm2) with excellent retention (only 5.4% loss after 5000 cycles) and Coulombic efficiency (93.1%). In addition, a five-fold enhancement in the capacitance of VGNs (0.64 to 3.31 mF/cm2) with a reduced internal resistance is achieved by the combination of KOH activation and the hybrid electrolyte.

  20. Enhanced bag of words using multilevel k-means for human activity recognition

    Directory of Open Access Journals (Sweden)

    Motasem Elshourbagy

    2016-07-01

    Full Text Available This paper aims to enhance the bag of features in order to improve the accuracy of human activity recognition. In this paper, human activity recognition process consists of four stages: local space time features detection, feature description, bag of features representation, and SVMs classification. The k-means step in the bag of features is enhanced by applying three levels of clustering: clustering per video, clustering per action class, and clustering for the final code book. The experimental results show that the proposed method of enhancement reduces the time and memory requirements, and enables the use of all training data in the k-means clustering algorithm. The evaluation of accuracy of action classification on two popular datasets (KTH and Weizmann has been performed. In addition, the proposed method improves the human activity recognition accuracy by 5.57% on the KTH dataset using the same detector, descriptor, and classifier.

  1. Highly reproducible surface-enhanced Raman scattering-active Au nanostructures prepared by simple electrodeposition: origin of surface-enhanced Raman scattering activity and applications as electrochemical substrates.

    Science.gov (United States)

    Choi, Suhee; Ahn, Miri; Kim, Jongwon

    2013-05-24

    The fabrication of effective surface-enhanced Raman scattering (SERS) substrates has been the subject of intensive research because of their useful applications. In this paper, dendritic gold (Au) rod (DAR) structures prepared by simple one-step electrodeposition in a short time were examined as an effective SERS-active substrate. The SERS activity of the DAR surfaces was compared to that of other nanostructured Au surfaces with different morphologies, and its dependence on the structural variation of DAR structures was examined. These comparisonal investigations revealed that highly faceted sharp edge sites present on the DAR surfaces play a critical role in inducing a high SERS activity. The SERS enhancement factor was estimated to be greater than 10(5), and the detection limit of rhodamine 6G at DAR surfaces was 10(-8)M. The DAR surfaces exhibit excellent spot-to-spot and substrate-to-substrate SERS enhancement reproducibility, and their long-term stability is very good. It was also demonstrated that the DAR surfaces can be effectively utilized in electrochemical SERS systems, wherein a reversible SERS behavior was obtained during the cycling to cathodic potential regions. Considering the straightforward preparation of DAR substrates and the clean nature of SERS-active Au surfaces prepared in the absence of additives, we expect that DAR surfaces can be used as cost-effective SERS substrates in analytical and electrochemical applications. Copyright © 2013 Elsevier B.V. All rights reserved.

  2. Polypeptides having cellulolytic enhancing activity and polynucleotides encoding same

    Science.gov (United States)

    Maiyuran, Suchindra; Kramer, Randall; Harris, Paul

    2013-10-29

    The present invention relates to isolated polypeptides having cellulolytic enhancing activity and isolated polynucleotides encoding the polypeptides. The invention also relates to nucleic acid constructs, vectors, and host cells comprising the polynucleotides as well as methods of producing and using the polypeptides.

  3. Cross-sector cooperation in health-enhancing physical activity policymaking

    DEFF Research Database (Denmark)

    Hämäläinen, Riitta-Maija; Aro, Arja R.; Juel Lau, Cathrine

    2016-01-01

    in health-enhancing physical activity (HEPA) policies in six European Union (EU) member states. METHODS: Qualitative content analysis of HEPA policies and semi-structured interviews with key policymakers in six European countries. RESULTS: Cross-sector cooperation varied between EU member states within HEPA...

  4. Endoplasmic Reticulum Stress Caused by Lipoprotein Accumulation Suppresses Immunity against Bacterial Pathogens and Contributes to Immunosenescence

    Directory of Open Access Journals (Sweden)

    Jogender Singh

    2017-05-01

    Full Text Available The unfolded protein response (UPR is a stress response pathway that is activated upon increased unfolded and/or misfolded proteins in the endoplasmic reticulum (ER, and enhanced ER stress response prolongs life span and improves immunity. However, the mechanism by which ER stress affects immunity remains poorly understood. Using the nematode Caenorhabditis elegans, we show that mutations in the lipoproteins vitellogenins, which are homologs of human apolipoprotein B-100, resulted in upregulation of the UPR. Lipoprotein accumulation in the intestine adversely affects the immune response and the life span of the organism, suggesting that it could be a contributing factor to immunosenescence. We show that lipoprotein accumulation inhibited the expression of several immune genes encoding proteins secreted by the intestinal cells in an IRE-1-independent manner. Our studies provide a mechanistic explanation for adverse effects caused by protein aggregation and ER stress on immunity and highlight the role of an IRE-1-independent pathway in the suppression of the expression of genes encoding secreted proteins.

  5. An atlas of active enhancers across human cell types and tissues

    DEFF Research Database (Denmark)

    Andersson, Robin; Gebhard, Claudia; Miguel-Escalada, Irene

    2014-01-01

    Enhancers control the correct temporal and cell-type-specific activation of gene expression in multicellular eukaryotes. Knowing their properties, regulatory activity and targets is crucial to understand the regulation of differentiation and homeostasis. Here we use the FANTOM5 panel of samples, ...

  6. Replicating the EnhanceFitness physical activity program in Hawai`i's multicultural population, 2007-2010.

    Science.gov (United States)

    Tomioka, Michiyo; Sugihara, Naomi; Braun, Kathryn L

    2012-01-01

    Despite evidence of the benefits of regular physical activity, many older adults are not physically active. Health professionals are challenged to replicate evidence-based programs to address low levels of physical activity among members of their communities. EnhanceFitness is an evidence-based group exercise program developed in Seattle to increase the strength, flexibility, and balance of older adults. Hawai`i's Healthy Aging Partnership supported the rural island of Kaua`i to select, adapt, implement, and evaluate EnhanceFitness to increase physical activity among older adult residents (75% Asian/Pacific Islander [API]). Evaluation measures of the replication of EnhanceFitness included fidelity of EnhanceFitness delivery and participants' attendance, satisfaction with the program, confidence to exercise regularly, and pre-post fitness check measures of physical performance (chair stands, arm curls, and the up-and-go test). Between July 2007 and December 2010, 223 Kaua`i residents enrolled in EnhanceFitness; 178 (80%) participated at least 4 months and completed the 4-month fitness checks. EnhanceFitness classes were offered with a high degree of fidelity, and both API and white participants significantly improved their physical performance (chair stands, t = -11.06, P program and instructors and high confidence to continue to exercise regularly. EnhanceFitness is replicable in Hawai`i and increased physical performance among API and white older adults. This case study outlines a replication process that other communities can follow.

  7. Thrombopoietin contributes to enhanced platelet activation in cigarette smokers.

    Science.gov (United States)

    Lupia, Enrico; Bosco, Ornella; Goffi, Alberto; Poletto, Cesare; Locatelli, Stefania; Spatola, Tiziana; Cuccurullo, Alessandra; Montrucchio, Giuseppe

    2010-05-01

    Thrombopoietin (TPO) is a humoral growth factor that primes platelet activation in response to several agonists. We recently showed that TPO enhances platelet activation in unstable angina and sepsis. Aim of this study was to investigate the role of TPO in platelet function abnormalities described in cigarette smokers. In a case-control study we enrolled 20 healthy cigarette smokers and 20 nonsmokers, and measured TPO and C-reactive protein (CRP), as well as platelet-leukocyte binding and P-selectin expression. In vitro we evaluated the priming activity of smoker or control plasma on platelet activation, and the role of TPO in this effect. We then studied the effects of acute smoking and smoking cessation on TPO levels and platelet activation indices. Chronic cigarette smokers had higher circulating TPO levels than nonsmoking controls, as well as increased platelet-leukocyte binding, P-selectin expression, and CRP levels. Serum cotinine concentrations correlated with TPO concentrations, platelet-monocyte aggregates and P-selectin expression. In addition, TPO levels significantly correlated with ex vivo platelet-monocyte aggregation and P-selectin expression. In vitro, the plasma from cigarette smokers, but not from nonsmoking controls, primed platelet-monocyte binding, which was reduced when an inhibitor of TPO was used. We also found that acute smoking slightly increased TPO levels, but did not affect platelet-leukocyte binding, whereas smoking cessation induced a significant decrease in both circulating TPO and platelet-leukocyte aggregation. Elevated TPO contributes to enhance platelet activation and platelet-monocyte cross-talk in cigarette smokers. Copyright 2009 Elsevier Ireland Ltd. All rights reserved.

  8. Clinical and pathological outcomes after irreversible electroporation of the pancreas using two parallel plate electrodes: a porcine model.

    Science.gov (United States)

    Rombouts, Steffi J E; van Dijck, Willemijn P M; Nijkamp, Maarten W; Derksen, Tyche C; Brosens, Lodewijk A A; Hoogwater, Frederik J H; van Leeuwen, Maarten S; Borel Rinkes, Inne H M; van Hillegersberg, Richard; Wittkampf, Fred H; Molenaar, Izaak Q

    2017-12-01

    Irreversible electroporation (IRE) by inserting needles around the tumor as treatment for locally advanced pancreatic cancer entails several disadvantages, such as incomplete ablation due to field inhomogeneity, technical difficulties in needle placement and a risk of pancreatic fistula development. This experimental study evaluates outcomes of IRE using paddles in a porcine model. Six healthy pigs underwent laparotomy and were treated with 2 separate ablations (in head and tail of the pancreas). Follow-up consisted of clinical and laboratory parameters and contrast-enhanced computed tomography (ceCT) imaging. After 2 weeks, pancreatoduodenectomy was performed for histology and the pigs were terminated. All animals survived 14 days. None of the animals developed signs of infection or significant abdominal distention. Serum amylase and lipase peaked at day 1 postoperatively in all pigs, but normalized without signs of pancreatitis. On ceCT-imaging the ablation zone was visible as an ill-defined, hypodense lesion. No abscesses, cysts or ascites were seen. Histology showed a homogenous fibrotic lesion in all pigs. IRE ablation of healthy porcine pancreatic tissue using two plate electrodes is feasible and safe and creates a homogeneous fibrotic lesion. IRE-paddles should be tested on pancreatic adenocarcinoma to determine the effect in cancer tissue. Copyright © 2017. Published by Elsevier Ltd.

  9. Identification of Toyocamycin, an agent cytotoxic for multiple myeloma cells, as a potent inhibitor of ER stress-induced XBP1 mRNA splicing

    International Nuclear Information System (INIS)

    Ri, M; Tashiro, E; Oikawa, D; Shinjo, S; Tokuda, M; Yokouchi, Y; Narita, T; Masaki, A; Ito, A; Ding, J; Kusumoto, S; Ishida, T; Komatsu, H; Shiotsu, Y; Ueda, R; Iwawaki, T; Imoto, M; Iida, S

    2012-01-01

    The IRE1α-XBP1 pathway, a key component of the endoplasmic reticulum (ER) stress response, is considered to be a critical regulator for survival of multiple myeloma (MM) cells. Therefore, the availability of small-molecule inhibitors targeting this pathway would offer a new chemotherapeutic strategy for MM. Here, we screened small-molecule inhibitors of ER stress-induced XBP1 activation, and identified toyocamycin from a culture broth of an Actinomycete strain. Toyocamycin was shown to suppress thapsigargin-, tunicamycin- and 2-deoxyglucose-induced XBP1 mRNA splicing in HeLa cells without affecting activating transcription factor 6 (ATF6) and PKR-like ER kinase (PERK) activation. Furthermore, although toyocamycin was unable to inhibit IRE1α phosphorylation, it prevented IRE1α-induced XBP1 mRNA cleavage in vitro. Thus, toyocamycin is an inhibitor of IRE1α-induced XBP1 mRNA cleavage. Toyocamycin inhibited not only ER stress-induced but also constitutive activation of XBP1 expression in MM lines as well as primary samples from patients. It showed synergistic effects with bortezomib, and induced apoptosis of MM cells including bortezomib-resistant cells at nanomolar levels in a dose-dependent manner. It also inhibited growth of xenografts in an in vivo model of human MM. Taken together, our results suggest toyocamycin as a lead compound for developing anti-MM therapy and XBP1 as an appropriate molecular target for anti-MM therapy

  10. Contrast-enhanced ultrasonography for the determination of Crohn’s disease activity – preliminary experience

    Science.gov (United States)

    Białecki, Marcin; Białecka, Agnieszka; Laskowska, Katarzyna; Kłopocka, Maria; Liebert, Ariel; Lemanowicz, Adam; Serafin, Zbigniew

    2014-01-01

    Summary Background Contrast-enhanced ultrasound (CEUS) is a recent non-invasive modality, which may partially replace currently used techniques (endoscopy, CT enterography and MR enterography) in the diagnostics and assessment of Crohn’s disease (CD). The aim of the study was to analyze early experience in the use of CEUS for the measurement of activity and staging of CD. Material/Methods Eleven patients previously diagnosed with CD were included in the study. They underwent contrast-enhanced ultrasonography (SonoVue, Bracco), low-dose CT enterography (LDCTE), assessment of laboratory markers of inflammation and clinical CD activity index (CDAI). Contrast enhancement was evaluated using a semi-quantitative method and a quantitative method that included measurement of peak enhancement (PE), enhancement curve rise time (RT) and wash-in-rate (WiR). Results Ileal wall thickening was observed in all patients. Semi-quantitative method was used to observe CD activity in CEUS in 10 cases that perfectly matched LDCTE findings. There was a moderate positive correlation between PE and CDAI (r=0.65, p<0.001). There was no significant relationship between perfusion parameters and laboratory markers of inflammation. Conclusions CEUS is a promising modality for non-invasive assessment of pathologic ileal vascularization in the course of Crohn’s disease. Intensity of enhancement in CEUS reflects activity of the disease detected in LDCTE and correlates with CDAI. PMID:24723988

  11. Contrast-enhanced ultrasonography for the determination of Crohn’s disease activity – preliminary experience

    International Nuclear Information System (INIS)

    Białecki, Marcin; Białecka, Agnieszka; Laskowska, Katarzyna; Kłopocka, Maria; Liebert, Ariel; Lemanowicz, Adam; Serafin, Zbigniew

    2014-01-01

    Contrast-enhanced ultrasound (CEUS) is a recent non-invasive modality, which may partially replace currently used techniques (endoscopy, CT enterography and MR enterography) in the diagnostics and assessment of Crohn’s disease (CD). The aim of the study was to analyze early experience in the use of CEUS for the measurement of activity and staging of CD. Eleven patients previously diagnosed with CD were included in the study. They underwent contrast-enhanced ultrasonography (SonoVue, Bracco), low-dose CT enterography (LDCTE), assessment of laboratory markers of inflammation and clinical CD activity index (CDAI). Contrast enhancement was evaluated using a semi-quantitative method and a quantitative method that included measurement of peak enhancement (PE), enhancement curve rise time (RT) and wash-in-rate (WiR). Ileal wall thickening was observed in all patients. Semi-quantitative method was used to observe CD activity in CEUS in 10 cases that perfectly matched LDCTE findings. There was a moderate positive correlation between PE and CDAI (r=0.65, p<0.001). There was no significant relationship between perfusion parameters and laboratory markers of inflammation. CEUS is a promising modality for non-invasive assessment of pathologic ileal vascularization in the course of Crohn’s disease. Intensity of enhancement in CEUS reflects activity of the disease detected in LDCTE and correlates with CDAI

  12. Identification of activated enhancers and linked transcription factors in breast, prostate, and kidney tumors by tracing enhancer networks using epigenetic traits.

    Science.gov (United States)

    Rhie, Suhn Kyong; Guo, Yu; Tak, Yu Gyoung; Yao, Lijing; Shen, Hui; Coetzee, Gerhard A; Laird, Peter W; Farnham, Peggy J

    2016-01-01

    Although technological advances now allow increased tumor profiling, a detailed understanding of the mechanisms leading to the development of different cancers remains elusive. Our approach toward understanding the molecular events that lead to cancer is to characterize changes in transcriptional regulatory networks between normal and tumor tissue. Because enhancer activity is thought to be critical in regulating cell fate decisions, we have focused our studies on distal regulatory elements and transcription factors that bind to these elements. Using DNA methylation data, we identified more than 25,000 enhancers that are differentially activated in breast, prostate, and kidney tumor tissues, as compared to normal tissues. We then developed an analytical approach called Tracing Enhancer Networks using Epigenetic Traits that correlates DNA methylation levels at enhancers with gene expression to identify more than 800,000 genome-wide links from enhancers to genes and from genes to enhancers. We found more than 1200 transcription factors to be involved in these tumor-specific enhancer networks. We further characterized several transcription factors linked to a large number of enhancers in each tumor type, including GATA3 in non-basal breast tumors, HOXC6 and DLX1 in prostate tumors, and ZNF395 in kidney tumors. We showed that HOXC6 and DLX1 are associated with different clusters of prostate tumor-specific enhancers and confer distinct transcriptomic changes upon knockdown in C42B prostate cancer cells. We also discovered de novo motifs enriched in enhancers linked to ZNF395 in kidney tumors. Our studies characterized tumor-specific enhancers and revealed key transcription factors involved in enhancer networks for specific tumor types and subgroups. Our findings, which include a large set of identified enhancers and transcription factors linked to those enhancers in breast, prostate, and kidney cancers, will facilitate understanding of enhancer networks and mechanisms

  13. Slow-light enhancement of spontaneous emission in active photonic crystal waveguides

    DEFF Research Database (Denmark)

    Ek, Sara; Chen, Yaohui; Semenova, Elizaveta

    2012-01-01

    Photonic crystal defect waveguides with embedded active layers containing single or multiple quantum wells or quantum dots have been fabricated. Spontaneous emission spectra are enhanced close to the bandedge, consistently with the enhancement of gain by slow light effects. These are promising...... results for future compact devices for terabit/s communication, such as miniaturised semiconductor optical amplifiers and mode-locked lasers....

  14. IL-6 Inhibition Reduces STAT3 Activation and Enhances the Antitumor Effect of Carboplatin

    Directory of Open Access Journals (Sweden)

    Zhi-Yong Wang

    2016-01-01

    Full Text Available Recent studies suggest that tumor-associated macrophage-produced IL-6 is an important mediator within the tumor microenvironment that promotes tumor growth. The activation of IL-6/STAT3 axis has been associated with chemoresistance and poor prognosis of a variety of cancers including colorectal carcinoma and thus serves as a potential immunotherapeutic target for cancer treatment. However, it is not fully understood whether anticytokine therapy could reverse chemosensitivity and enhance the suppressive effect of chemotherapy on tumor growth. In this study, we aimed to investigate the effect of IL-6 inhibition therapy on the antitumor effect of carboplatin. Enhanced expression of IL-6 and activation of STAT3 were observed in human colorectal carcinoma samples compared to normal colorectal tissue, with higher levels of IL-6/STAT3 in low grade carcinomas. Treatment of carboplatin (CBP dose-dependently increased IL-6 production and STAT3 activation in human colorectal LoVo cells. Blockade of IL-6 with neutralizing antibody enhanced chemosensitivity of LoVo cells to carboplatin as evidenced by increased cell apoptosis. IL-6 blockade abolished carboplatin-induced STAT3 activation. IL-6 blockade and carboplatin synergistically reduced cyclin D1 expression and enhanced caspase-3 activity in LoVo cells. Our results suggest that inhibition of IL-6 may enhance chemosensitivity of colon cancers with overactive STAT3 to platinum agents.

  15. Does the Room Matter? Active Learning in Traditional and Enhanced Lecture Spaces

    Science.gov (United States)

    Stoltzfus, Jon R.; Libarkin, Julie

    2016-01-01

    SCALE-UP–type classrooms, originating with the Student-Centered Active Learning Environment with Upside-down Pedagogies project, are designed to facilitate active learning by maximizing opportunities for interactions between students and embedding technology in the classroom. Positive impacts when active learning replaces lecture are well documented, both in traditional lecture halls and SCALE-UP–type classrooms. However, few studies have carefully analyzed student outcomes when comparable active learning–based instruction takes place in a traditional lecture hall and a SCALE-UP–type classroom. Using a quasi-experimental design, we compared student perceptions and performance between sections of a nonmajors biology course, one taught in a traditional lecture hall and one taught in a SCALE-UP–type classroom. Instruction in both sections followed a flipped model that relied heavily on cooperative learning and was as identical as possible given the infrastructure differences between classrooms. Results showed that students in both sections thought that SCALE-UP infrastructure would enhance performance. However, measures of actual student performance showed no difference between the two sections. We conclude that, while SCALE-UP–type classrooms may facilitate implementation of active learning, it is the active learning and not the SCALE-UP infrastructure that enhances student performance. As a consequence, we suggest that institutions can modify existing classrooms to enhance student engagement without incorporating expensive technology. PMID:27909018

  16. The second extracellular loop of the adenosine A1 receptor mediates activity of allosteric enhancers.

    Science.gov (United States)

    Kennedy, Dylan P; McRobb, Fiona M; Leonhardt, Susan A; Purdy, Michael; Figler, Heidi; Marshall, Melissa A; Chordia, Mahendra; Figler, Robert; Linden, Joel; Abagyan, Ruben; Yeager, Mark

    2014-02-01

    Allosteric enhancers of the adenosine A1 receptor amplify signaling by orthosteric agonists. Allosteric enhancers are appealing drug candidates because their activity requires that the orthosteric site be occupied by an agonist, thereby conferring specificity to stressed or injured tissues that produce adenosine. To explore the mechanism of allosteric enhancer activity, we examined their action on several A1 receptor constructs, including (1) species variants, (2) species chimeras, (3) alanine scanning mutants, and (4) site-specific mutants. These findings were combined with homology modeling of the A1 receptor and in silico screening of an allosteric enhancer library. The binding modes of known docked allosteric enhancers correlated with the known structure-activity relationship, suggesting that these allosteric enhancers bind to a pocket formed by the second extracellular loop, flanked by residues S150 and M162. We propose a model in which this vestibule controls the entry and efflux of agonists from the orthosteric site and agonist binding elicits a conformational change that enables allosteric enhancer binding. This model provides a mechanism for the observations that allosteric enhancers slow the dissociation of orthosteric agonists but not antagonists.

  17. NSCT BASED LOCAL ENHANCEMENT FOR ACTIVE CONTOUR BASED IMAGE SEGMENTATION APPLICATION

    Directory of Open Access Journals (Sweden)

    Hiren Mewada

    2010-08-01

    Full Text Available Because of cross-disciplinary nature, Active Contour modeling techniques have been utilized extensively for the image segmentation. In traditional active contour based segmentation techniques based on level set methods, the energy functions are defined based on the intensity gradient. This makes them highly sensitive to the situation where the underlying image content is characterized by image nonhomogeneities due to illumination and contrast condition. This is the most difficult problem to make them as fully automatic image segmentation techniques. This paper introduces one of the approaches based on image enhancement to this problem. The enhanced image is obtained using NonSubsampled Contourlet Transform, which improves the edges strengths in the direction where the illumination is not proper and then active contour model based on level set technique is utilized to segment the object. Experiment results demonstrate that proposed method can be utilized along with existing active contour model based segmentation method under situation characterized by intensity non-homogeneity to make them fully automatic.

  18. Nerve growth factor enhances the CRE-dependent transcriptional activity activated by nobiletin in PC12 cells.

    Science.gov (United States)

    Takito, Jiro; Kimura, Junko; Kajima, Koji; Uozumi, Nobuyuki; Watanabe, Makoto; Yokosuka, Akihito; Mimaki, Yoshihiro; Nakamura, Masanori; Ohizumi, Yasushi

    2016-07-01

    Prevention and treatment of Alzheimer disease are urgent problems for elderly people in developed countries. We previously reported that nobiletin, a poly-methoxylated flavone from the citrus peel, improved the symptoms in various types of animal models of memory loss and activated the cAMP responsive element (CRE)-dependent transcription in PC12 cells. Nobiletin activated the cAMP/PKA/MEK/Erk/MAPK signaling pathway without using the TrkA signaling activated by nerve growth factor (NGF). Here, we examined the effect of combination of nobiletin and NGF on the CRE-dependent transcription in PC12 cells. Although NGF alone had little effect on the CRE-dependent transcription, NGF markedly enhanced the CRE-dependent transcription induced by nobiletin. The NGF-induced enhancement was neutralized by a TrkA antagonist, K252a. This effect of NGF was effective on the early signaling event elicited by nobiletin. These results suggested that there was crosstalk between NGF and nobiletin signaling in activating the CRE-dependent transcription in PC12 cells.

  19. Porous-ZnO-Nanobelt Film as Recyclable Photocatalysts with Enhanced Photocatalytic Activity

    Directory of Open Access Journals (Sweden)

    Wang Min

    2010-01-01

    Full Text Available Abstract In this article, the porous-ZnO-nanobelt film was synthesized by oxidizing the ZnSe-nanobelt film in air. The experiment results show that the porous-ZnO-nanobelt film possesses enhanced photocatalytic activity compared with the ZnO-nanobelt film, and can be used as recyclable photocatalysts. The enhanced photocatalytic activity of the porous-ZnO-nanobelt film is attributed to the increased surface area. Therefore, turning the 1D-nanostructure film into porous one may be a feasible approach to meet the demand of photocatalyst application.

  20. Enhancing learning in geosciences and water engineering via lab activities

    Science.gov (United States)

    Valyrakis, Manousos; Cheng, Ming

    2016-04-01

    This study focuses on the utilisation of lab based activities to enhance the learning experience of engineering students studying Water Engineering and Geosciences. In particular, the use of modern highly visual and tangible presentation techniques within an appropriate laboratory based space are used to introduce undergraduate students to advanced engineering concepts. A specific lab activity, namely "Flood-City", is presented as a case study to enhance the active engagement rate, improve the learning experience of the students and better achieve the intended learning objectives of the course within a broad context of the engineering and geosciences curriculum. Such activities, have been used over the last few years from the Water Engineering group @ Glasgow, with success for outreach purposes (e.g. Glasgow Science Festival and demos at the Glasgow Science Centre and Kelvingrove museum). The activity involves a specific setup of the demonstration flume in a sand-box configuration, with elements and activities designed so as to gamely the overall learning activity. Social media platforms can also be used effectively to the same goals, particularly in cases were the students already engage in these online media. To assess the effectiveness of this activity a purpose designed questionnaire is offered to the students. Specifically, the questionnaire covers several aspects that may affect student learning, performance and satisfaction, such as students' motivation, factors to effective learning (also assessed by follow-up quizzes), and methods of communication and assessment. The results, analysed to assess the effectiveness of the learning activity as the students perceive it, offer a promising potential for the use of such activities in outreach and learning.

  1. Gene activation regresses atherosclerosis, promotes health, and enhances longevity

    Directory of Open Access Journals (Sweden)

    Luoma Pauli V

    2010-07-01

    Full Text Available Abstract Background Lifestyle factors and pharmacological compounds activate genetic mechanisms that influence the development of atherosclerotic and other diseases. This article reviews studies on natural and pharmacological gene activation that promotes health and enhances longevity. Results Living habits including healthy diet and regular physical activity, and pharmacotherapy, upregulate genes encoding enzymes and apolipoprotein and ATP-binding cassette transporters, acting in metabolic processes that promote health and increase survival. Cytochrome P450-enzymes, physiological factors in maintaining cholesterol homeostasis, generate oxysterols for the elimination of surplus cholesterol. Hepatic CTP:phosphocholine cytidylyltransferase-α is an important regulator of plasma HDL-C level. Gene-activators produce plasma lipoprotein profile, high HDL-C, HDL2-C and HDL-C/cholesterol ratio, which is typical of low risk of atherosclerotic disease, and also of exceptional longevity together with reduced prevalence of cardiovascular, metabolic and other diseases. High HDL contributes to protection against inflammation, oxidation and thrombosis, and associates with good cognitive function in very old people. Avoiding unhealthy stress and managing it properly promotes health and increases life expectancy. Conclusions Healthy living habits and gene-activating xenobiotics upregulate mechanisms that produce lipoprotein pattern typical of very old people and enhance longevity. Lipoprotein metabolism and large HDL2 associate with the process of living a very long life. Major future goals for health promotion are the improving of commitment to both wise lifestyle choices and drug therapy, and further the developing of new and more effective and well tolerated drugs and treatments.

  2. Contrast-enhanced ultrasound imaging of active bleeding associated with hepatic and splenic trauma.

    Science.gov (United States)

    Lv, F; Tang, J; Luo, Y; Li, Z; Meng, X; Zhu, Z; Li, T

    2011-10-01

    The aim of this study was to evaluate contrast-enhanced ultrasound (CEUS) imaging of active bleeding from hepatic and splenic trauma. Three hundred and ninety-two patients with liver or/and spleen trauma (179 liver and 217 spleen injuries), who underwent CEUS examinations following contrast-enhanced computed tomography (CT), were enrolled in this retrospective study over a period of >4 years. CEUS detected contrast medium extravasation or pooling in 16% (63/396) of liver or spleen lesions in 61 patients, which was confirmed by contrast-enhanced CT. Special attention was paid to observing the presence, location, and characteristics of the extravasated or pooled contrast medium. The CEUS detection rate for active bleeding was not different from that of contrast-enhanced CT (p=0.333). Information from surgery, minimally invasive treatment and conservative treatment was used as reference standard, and the sensitivities of the two techniques were not different (p=0.122). Of 63 lesions in 61 patients, CEUS showed that 74.6% (47/63) (21 liver lesions and 26 spleen lesions) presented contrast medium extravasation or pooling, both in the organ and out the capsule, in 14.3% (9/63) and only outside the capsule in 11.1% (7/63). CEUS imaging of active bleeding from hepatic and splenic trauma presented various characteristics, and the sizes and shapes of the active bleeding due to contrast medium extravasation or pooling were variable. CEUS can show the active bleeding associated with hepatic and splenic trauma with various imaging characteristics, thus making it possible to diagnose active bleeding using CEUS.

  3. Epigenetic switch involved in activation of pioneer factor FOXA1-dependent enhancers

    Science.gov (United States)

    Sérandour, Aurélien A.; Avner, Stéphane; Percevault, Frédéric; Demay, Florence; Bizot, Maud; Lucchetti-Miganeh, Céline; Barloy-Hubler, Frédérique; Brown, Myles; Lupien, Mathieu; Métivier, Raphaël; Salbert, Gilles; Eeckhoute, Jérôme

    2011-01-01

    Transcription factors (TFs) bind specifically to discrete regions of mammalian genomes called cis-regulatory elements. Among those are enhancers, which play key roles in regulation of gene expression during development and differentiation. Despite the recognized central regulatory role exerted by chromatin in control of TF functions, much remains to be learned regarding the chromatin structure of enhancers and how it is established. Here, we have analyzed on a genomic-scale enhancers that recruit FOXA1, a pioneer transcription factor that triggers transcriptional competency of these cis-regulatory sites. Importantly, we found that FOXA1 binds to genomic regions showing local DNA hypomethylation and that its cell-type-specific recruitment to chromatin is linked to differential DNA methylation levels of its binding sites. Using neural differentiation as a model, we showed that induction of FOXA1 expression and its subsequent recruitment to enhancers is associated with DNA demethylation. Concomitantly, histone H3 lysine 4 methylation is induced at these enhancers. These epigenetic changes may both stabilize FOXA1 binding and allow for subsequent recruitment of transcriptional regulatory effectors. Interestingly, when cloned into reporter constructs, FOXA1-dependent enhancers were able to recapitulate their cell type specificity. However, their activities were inhibited by DNA methylation. Hence, these enhancers are intrinsic cell-type-specific regulatory regions of which activities have to be potentiated by FOXA1 through induction of an epigenetic switch that includes notably DNA demethylation. PMID:21233399

  4. Intelligent Architecture for Enhanced Observability for Active Distribution System

    DEFF Research Database (Denmark)

    Pokhrel, Basanta Raj; Nainar, Karthikeyan; Bak-Jensen, Birgitte

    2017-01-01

    There is a rapid increase of renewable energy resources (RE) and demand response resources (DRR) in the distribution networks. This is challenging for the reliable and stable operation of the grid. So, to ensure secure, optimized and economical operation in such active distribution grids they need...... for active distribution network which satisfies the need for higher observability reach with less field observation. Improved state estimation with composite load forecasting model is aimed for enhanced observability. This paper also summarizes the application of intelligent architecture in the operation...

  5. Capacitance enhancement of polyaniline coated curved-graphene supercapacitors in a redox-active electrolyte

    KAUST Repository

    Chen, Wei; Baby, Rakhi Raghavan; Alshareef, Husam N.

    2013-01-01

    We show, for the first time, a redox-active electrolyte in combination with a polyaniline-coated curved graphene active material to achieve significant enhancement in the capacitance (36-92% increase) compared to supercapacitors that lack the redox-active

  6. Aminoglycosylation can enhance the G-quadruplex binding activity of epigallocatechin.

    Directory of Open Access Journals (Sweden)

    Li-Ping Bai

    Full Text Available With the aim of enhancing G-quadruplex binding activity, two new glucosaminosides (16, 18 of penta-methylated epigallocatechin were synthesized by chemical glycosylation. Subsequent ESI-TOF-MS analysis demonstrated that these two glucosaminoside derivatives exhibit much stronger binding activity to human telomeric DNA and RNA G-quadruplexes than their parent structure (i.e., methylated EGC (14 as well as natural epigallocatechin (EGC, 6. The DNA G-quadruplex binding activity of 16 and 18 is even more potent than strong G-quadruplex binder quercetin, which has a more planar structure. These two synthetic compounds also showed a higher binding strength to human telomeric RNA G-quadruplex than its DNA counterpart. Analysis of the structure-activity relationship revealed that the more basic compound, 16, has a higher binding capacity with DNA and RNA G-quadruplexes than its N-acetyl derivative, 18, suggesting the importance of the basicity of the aminoglycoside for G-quadruplex binding activity. Molecular docking simulation predicted that the aromatic ring of 16 π-stacks with the aromatic ring of guanine nucleotides, with the glucosamine moiety residing in the groove of G-quadruplex. This research indicates that glycosylation of natural products with aminosugar can significantly enhance their G-quadruplex binding activities, thus is an effective way to generate small molecules targeting G-quadruplexes in nucleic acids. In addition, this is the first report that green tea catechin can bind to nucleic acid G-quadruplex structures.

  7. Capacitance enhancement of polyaniline coated curved-graphene supercapacitors in a redox-active electrolyte

    Science.gov (United States)

    Chen, Wei; Rakhi, R. B.; Alshareef, H. N.

    2013-05-01

    We show, for the first time, a redox-active electrolyte in combination with a polyaniline-coated curved graphene active material to achieve significant enhancement in the capacitance (36-92% increase) compared to supercapacitors that lack the redox-active contribution from the electrolyte. The supercapacitors based on the redox-active electrolyte also exhibit excellent rate capability and very long cycling performance (>50 000 cycles).We show, for the first time, a redox-active electrolyte in combination with a polyaniline-coated curved graphene active material to achieve significant enhancement in the capacitance (36-92% increase) compared to supercapacitors that lack the redox-active contribution from the electrolyte. The supercapacitors based on the redox-active electrolyte also exhibit excellent rate capability and very long cycling performance (>50 000 cycles). Electronic supplementary information (ESI) available: Experimental section, supporting figures including SEM, TEM, XPS, BET, CV and CD curves and a summary table of capacitance. See DOI: 10.1039/c3nr00773a

  8. Thiourea-Modified TiO2 Nanorods with Enhanced Photocatalytic Activity

    Directory of Open Access Journals (Sweden)

    Xiaofeng Wu

    2016-02-01

    Full Text Available Semiconductor TiO2 photocatalysis has attracted much attention due to its potential application in solving the problems of environmental pollution. In this paper, thiourea (CH4N2S modified anatase TiO2 nanorods were fabricated by calcination of the mixture of TiO2 nanorods and thiourea at 600 °C for 2 h. It was found that only N element was doped into the lattice of TiO2 nanorods. With increasing the weight ratio of thiourea to TiO2 (R from 0 to 8, the light-harvesting ability of the photocatalyst steady increases. Both the crystallization and photocatalytic activity of TiO2 nanorods increase first and then decrease with increase in R value, and R2 sample showed the highest crystallization and photocatalytic activity in degradation of Brilliant Red X3B (X3B and Rhodamine B (RhB dyes under visible light irradiation (λ > 420 nm. The increased visible-light photocatalytic activity of the prepared N-doped TiO2 nanorods is due to the synergistic effects of the enhanced crystallization, improved light-harvesting ability and reduced recombination rate of photo-generated electron-hole pairs. Note that the enhanced visible photocatalytic activity of N-doped nanorods is not based on the scarification of their UV photocatalytic activity.

  9. Gamma radiation induced enhancement in the antioxidant and radioprotective activities of flavonoids

    International Nuclear Information System (INIS)

    Arul Anantha Kumar, A.; Sonwani, Swetha; Bakkiam, D.

    2018-01-01

    Recently γ-radiation has been used as a tool to induce structural changes in natural biomolecules to enhance their biological and physiological properties. Flavonoids are a family of plant derived polyphenolic compounds having considerable scientific and therapeutic importance. Structurally they are the benzo-γ-pyrone derivatives containing phenolic and pyrane rings. Flavonoid radioprotection is an intense area of research thanks to features like natural origin, effectiveness at non-toxic dose levels and lack of side effects. But till date no report is available on the effect of γ-radiation mediated enhancement in radioprotection activity of flavonoids. In view of this the present study was carried out to determine the γ-radiation induced structural changes in selected flavonoids i.e. apigenin, naringenin and genistein and also to explore the possibility of enhancement in their antioxidant and radioprotective activities

  10. Enhancement of collaboration activities utilizing 21st century learning design rubric

    Science.gov (United States)

    Cubero, Dave D.; Gargar, Clare V., Lady; Nallano, Gerlett Grace D.; Magsayo, Joy R.; Guarin, Rica Mae B.; Lahoylahoy, Myrna E.

    2018-01-01

    Twenty first century learners have incredibly diverse learning interests, needs, and aspirations. Engaging middle school students and sculpting successful, confident, and creative learners is a constant endeavor for educators [4]. In the 21st century classroom environments in which students can develop the skills they need in workplace. Collaboration occurs when students work together to create, discuss challenge and develop deeper critical thinking. In today's workplace, collaboration is essential as only few tasks are completed alone (Calgary and Park, 2016). The collaborative project-based curriculum used in this classroom develops the higher order thinking skills, effective communication skills, and knowledge of technology that students will need in the 21st century workplace. The study therefore aims to promote collaboration skills among learners as it is deemed as one of the top 21st century skills. Collaborative learning unleashes a unique intellectual and social synergy. This study aims to enhance the collaborative skills of students through conducting collaboration activities in learning the Ecosystem. This research utilizes pretest-posttest and employs descriptive research designs. It uses modified activities about the lesson on Ecosystem and utilizes a Collaboration Rubric to rate the modified activities. The activities were rated by ten In-Service teachers and there are 105 students who participated in doing the activities. The paired t-test is then used to analyze the data. The In-Service teachers evaluated the 1st and 2nd adapted activity and are rated as fair. Thus, the modified activities were enhanced since the ratings of each activity did not meet the criterion of the collaboration rubric. As for the 3rd adapted activity is rated as excellent and is ready for implementation. The evaluators provided comments and suggestions such as producing colored pictures on the activities, omitting some questions, and making the words simpler to enhance the

  11. Handling and safety enhancement of race cars using active aerodynamic systems

    Science.gov (United States)

    Diba, Fereydoon; Barari, Ahmad; Esmailzadeh, Ebrahim

    2014-09-01

    A methodology is presented in this work that employs the active inverted wings to enhance the road holding by increasing the downward force on the tyres. In the proposed active system, the angles of attack of the vehicle's wings are adjusted by using a real-time controller to increase the road holding and hence improve the vehicle handling. The handling of the race car and safety of the driver are two important concerns in the design of race cars. The handling of a vehicle depends on the dynamic capabilities of the vehicle and also the pneumatic tyres' limitations. The vehicle side-slip angle, as a measure of the vehicle dynamic safety, should be narrowed into an acceptable range. This paper demonstrates that active inverted wings can provide noteworthy dynamic capabilities and enhance the safety features of race cars. Detailed analytical study and formulations of the race car nonlinear model with the airfoils are presented. Computer simulations are carried out to evaluate the performance of the proposed active aerodynamic system.

  12. Novel Chiroptical Analysis of Hemoglobin by Surface Enhanced Resonance Raman Optical Activity Spectroscopy

    DEFF Research Database (Denmark)

    Brazhe, Nadezda; Brazhe, Alexey; Sosnovtseva, Olga

    2010-01-01

    The metalloprotein hemoglobin (Hb) was studied using surface enhanced resonance Raman spectroscopy (SERRS) and surface enhanced resonance Raman optical activity (SERROA). The SERROA results are analyzed and compared with the SERRS, and the later to the resonance Raman (RRS) performed on Hb...

  13. Enhanced persistency of resting and active periods of locomotor activity in schizophrenia.

    Directory of Open Access Journals (Sweden)

    Wataru Sano

    Full Text Available Patients with schizophrenia frequently exhibit behavioral abnormalities associated with its pathological symptoms. Therefore, a quantitative evaluation of behavioral dynamics could contribute to objective diagnoses of schizophrenia. However, such an approach has not been fully established because of the absence of quantitative biobehavioral measures. Recently, we studied the dynamical properties of locomotor activity, specifically how resting and active periods are interwoven in daily life. We discovered universal statistical laws ("behavioral organization" and their alterations in patients with major depressive disorder. In this study, we evaluated behavioral organization of schizophrenic patients (n = 19 and healthy subjects (n = 11 using locomotor activity data, acquired by actigraphy, to investigate whether the laws could provide objective and quantitative measures for a possible diagnosis and assessment of symptoms. Specifically, we evaluated the cumulative distributions of resting and active periods, defined as the periods with physical activity counts successively below and above a predefined threshold, respectively. Here we report alterations in the laws governing resting and active periods; resting periods obeyed a power-law cumulative distribution with significantly lower parameter values (power-law scaling exponents, whereas active periods followed a stretched exponential distribution with significantly lower parameter values (stretching exponents, in patients. Our findings indicate enhanced persistency of both lower and higher locomotor activity periods in patients with schizophrenia, probably reflecting schizophrenic pathophysiology.

  14. 77 FR 33546 - Agency Information Collection Activities: Proposed Request

    Science.gov (United States)

    2012-06-06

    ... seek personal information from SSA records, or who register to participate in SSA's online business... third parties who are registering for SSA's online business services. Average burden Estimated Modality...-0626. The IRES System verifies the identity of individuals, businesses, organizations, entities, and...

  15. A new generation of pPRIG-based retroviral vectors

    Directory of Open Access Journals (Sweden)

    Boulukos Kim E

    2007-11-01

    Full Text Available Abstract Background Retroviral vectors are valuable tools for gene transfer. Particularly convenient are IRES-containing retroviral vectors expressing both the protein of interest and a marker protein from a single bicistronic mRNA. This coupled expression increases the relevance of tracking and/or selection of transduced cells based on the detection of a marker protein. pAP2 is a retroviral vector containing eGFP downstream of a modified IRES element of EMCV origin, and a CMV enhancer-promoter instead of the U3 region of the 5'LTR, which increases its efficiency in transient transfection. However, pAP2 contains a limited multicloning site (MCS and shows weak eGFP expression, which previously led us to engineer an improved version, termed pPRIG, harboring: i the wild-type ECMV IRES sequence, thereby restoring its full activity; ii an optimized MCS flanked by T7 and SP6 sequences; and iii a HA tag encoding sequence 5' of the MCS (pPRIG HAa/b/c. Results The convenience of pPRIG makes it a good basic vector to generate additional derivatives for an extended range of use. Here we present several novel pPRIG-based vectors (collectively referred to as PRIGs in which : i the HA tag sequence was inserted in the three reading frames 3' of the MCS (3'HA PRIGs; ii a functional domain (ER, VP16 or KRAB was inserted either 5' or 3' of the MCS (« modular » PRIGs; iii eGFP was replaced by either eCFP, eYFP, mCherry or puro-R (« single color/resistance » PRIGs; and iv mCherry, eYFP or eGFP was inserted 5' of the MCS of the IRES-eGFP, IRES-eCFP or IRES-Puro-R containing PRIGs, respectively (« dual color/selection » PRIGs. Additionally, some of these PRIGs were also constructed in a pMigR MSCV background which has been widely used in pluripotent cells. Conclusion These novel vectors allow for straightforward detection of any expressed protein (3'HA PRIGs, for functional studies of chimeric proteins (« modular » PRIGs, for multiple transductions and

  16. Intraperitoneal administration of the globular adiponectin gene ameliorates diabetic nephropathy in Wistar rats.

    Science.gov (United States)

    Yuan, Fang; Liu, Ying-Hong; Liu, Fu-You; Peng, You-Ming; Tian, Jun-Wei

    2014-06-01

    The present study investigated the potential effects of the long-term expression of exogenous adiponectin (ADPN) on normal and diabetic kidneys. Type 2 diabetes mellitus models were induced by high-lipid and high-sucrose feeding plus intraperitoneal injection of streptozotocin. The recombinant plasmid pIRES2-EGFP-gAd, which is able to co-express globular ADPN (gAd) and enhanced green fluorescent protein (EGFP), was intraperitoneally injected into rat models mediated by Lipofectamine. In total, 32 Wistar rats were randomly assigned into four groups: the normal control group, the diabetes group, the diabetes group treated with pIRES2-EGFP-gAd and the diabetes group treated with pIRES2-EGFP. After 12 weeks, serum biochemistry and urine albumin levels were measured. The kidneys were collected to assess the generation of reactive oxygen species (ROS) and the renal pathological changes were observed by light microcopy. The protein expression of endothelial nitric oxide synthase (eNOS), transforming growth factor-β1 (TGF-β1) and phosphorylated adenosine monophosphate-activated protein kinase (p-AMPK) were determined by an immunohistochemical staining method and western blot analysis. Intraperitoneal injection of the human gAd gene via Lipofectamine resulted in abundant ADPN protein in the kidney. In the diabetic rats, the delivery of the exogenous gAd gene ameliorated the progression of diabetic nephropathy (DN). ADPN attenuated urine albumin excretion in the diabetic rats. ADPN also mitigated glomerular mesangial expansion, reduced the generation of ROS and prevented interstitial fibrosis. In addition, the expression of gAd inhibited the renal expression of TGF-β1, promoted the protein expression of eNOS and activated the opening of the AMPK signaling pathway in the renal tissues of the diabetic rats. Despite the effects of ADPN on DN being controversial, these observations indicate that the supplementation of ADPN is beneficial in ameliorating DN in rats.

  17. Chronic alcohol consumption enhances iNKT cell maturation and activation

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Hui, E-mail: hzhang@wsu.edu; Zhang, Faya; Zhu, Zhaohui; Luong, Dung; Meadows, Gary G.

    2015-01-15

    Alcohol consumption exhibits diverse effects on different types of immune cells. NKT cells are a unique T cell population and play important immunoregulatory roles in different types of immune responses. The effects of chronic alcohol consumption on NKT cells remain to be elucidated. Using a mouse model of chronic alcohol consumption, we found that alcohol increases the percentage of NKT cells, especially iNKT cells in the thymus and liver, but not in the spleen or blood. Alcohol consumption decreases the percentage of NK1.1{sup −} iNKT cells in the total iNKT cell population in all of the tissues and organs examined. In the thymus, alcohol consumption increases the number of NK1.1{sup +}CD44{sup hi} mature iNKT cells but does not alter the number of NK1.1{sup −} immature iNKT cells. A BrdU incorporation assay shows that alcohol consumption increases the proliferation of thymic NK1.1{sup −} iNKT cells, especially the NK1.1{sup −}CD44{sup lo} Stage I iNKT cells. The percentage of NKG2A{sup +} iNKT cells increases in all of the tissues and organs examined; whereas CXCR3{sup +} iNKT cells only increases in the thymus of alcohol-consuming mice. Chronic alcohol consumption increases the percentage of IFN-γ-producing iNKT cells and increases the blood concentration of IFN-γ and IL-12 after in vivo α-galactosylceramide (αGalCer) stimulation. Consistent with the increased cytokine production, the in vivo activation of iNKT cells also enhances the activation of dendritic cells (DC) and NK, B, and T cells in the alcohol-consuming mice. Taken together the data indicate that chronic alcohol consumption enhances iNKT cell maturation and activation, which favors the Th1 immune response. - Highlights: • Chronic alcohol consumption increases iNKT cells in the thymus and liver • Chronic alcohol consumption enhances thymic Stage I iNKT cell proliferation • Chronic alcohol consumption enhances iNKT cell maturation in thymus and periphery • Chronic alcohol

  18. Chronic alcohol consumption enhances iNKT cell maturation and activation

    International Nuclear Information System (INIS)

    Zhang, Hui; Zhang, Faya; Zhu, Zhaohui; Luong, Dung; Meadows, Gary G.

    2015-01-01

    Alcohol consumption exhibits diverse effects on different types of immune cells. NKT cells are a unique T cell population and play important immunoregulatory roles in different types of immune responses. The effects of chronic alcohol consumption on NKT cells remain to be elucidated. Using a mouse model of chronic alcohol consumption, we found that alcohol increases the percentage of NKT cells, especially iNKT cells in the thymus and liver, but not in the spleen or blood. Alcohol consumption decreases the percentage of NK1.1 − iNKT cells in the total iNKT cell population in all of the tissues and organs examined. In the thymus, alcohol consumption increases the number of NK1.1 + CD44 hi mature iNKT cells but does not alter the number of NK1.1 − immature iNKT cells. A BrdU incorporation assay shows that alcohol consumption increases the proliferation of thymic NK1.1 − iNKT cells, especially the NK1.1 − CD44 lo Stage I iNKT cells. The percentage of NKG2A + iNKT cells increases in all of the tissues and organs examined; whereas CXCR3 + iNKT cells only increases in the thymus of alcohol-consuming mice. Chronic alcohol consumption increases the percentage of IFN-γ-producing iNKT cells and increases the blood concentration of IFN-γ and IL-12 after in vivo α-galactosylceramide (αGalCer) stimulation. Consistent with the increased cytokine production, the in vivo activation of iNKT cells also enhances the activation of dendritic cells (DC) and NK, B, and T cells in the alcohol-consuming mice. Taken together the data indicate that chronic alcohol consumption enhances iNKT cell maturation and activation, which favors the Th1 immune response. - Highlights: • Chronic alcohol consumption increases iNKT cells in the thymus and liver • Chronic alcohol consumption enhances thymic Stage I iNKT cell proliferation • Chronic alcohol consumption enhances iNKT cell maturation in thymus and periphery • Chronic alcohol consumption induces Th1 immune response upon i

  19. Mast cells enhance T cell activation: Importance of mast cell-derived TNF

    Science.gov (United States)

    Nakae, Susumu; Suto, Hajime; Kakurai, Maki; Sedgwick, Jonathon D.; Tsai, Mindy; Galli, Stephen J.

    2005-05-01

    Mast cells are not only important effector cells in immediate hypersensitivity reactions and immune responses to pathogens but also can contribute to T cell-mediated disorders. However, the mechanisms by which mast cells might influence T cells in such settings are not fully understood. We find that mast cells can enhance proliferation and cytokine production in multiple T cell subsets. Mast cell-dependent enhancement of T cell activation can be promoted by FcRI-dependent mast cell activation, TNF production by both mast cells and T cells, and mast cell-T cell contact. However, at high concentrations of cells, mast cells can promote T cell activation independent of IgE or TNF. Finally, mast cells also can promote T cell activation by means of soluble factors. These findings identify multiple mechanisms by which mast cells can influence T cell proliferation and cytokine production. allergy | asthma | autoimmunity | cytokines | immune response

  20. Inhibition of host cell translation elongation by Legionella pneumophila blocks the host cell unfolded protein response.

    Science.gov (United States)

    Hempstead, Andrew D; Isberg, Ralph R

    2015-12-08

    Cells of the innate immune system recognize bacterial pathogens by detecting common microbial patterns as well as pathogen-specific activities. One system that responds to these stimuli is the IRE1 branch of the unfolded protein response (UPR), a sensor of endoplasmic reticulum (ER) stress. Activation of IRE1, in the context of Toll-like receptor (TLR) signaling, induces strong proinflammatory cytokine induction. We show here that Legionella pneumophila, an intravacuolar pathogen that replicates in an ER-associated compartment, blocks activation of the IRE1 pathway despite presenting pathogen products that stimulate this response. L. pneumophila TLR ligands induced the splicing of mRNA encoding XBP1s, the main target of IRE1 activity. L. pneumophila was able to inhibit both chemical and bacterial induction of XBP1 splicing via bacterial translocated proteins that interfere with host protein translation. A strain lacking five translocated translation elongation inhibitors was unable to block XBP1 splicing, but this could be rescued by expression of a single such inhibitor, consistent with limitation of the response by translation elongation inhibitors. Chemical inhibition of translation elongation blocked pattern recognition receptor-mediated XBP1 splicing, mimicking the effects of the bacterial translation inhibitors. In contrast, host cell-promoted inhibition of translation initiation in response to the pathogen was ineffective in blocking XBP1 splicing, demonstrating the need for the elongation inhibitors for protection from the UPR. The inhibition of host translation elongation may be a common strategy used by pathogens to limit the innate immune response by interfering with signaling via the UPR.

  1. Unsaturated fatty acids lactose esters: cytotoxicity, permeability enhancement and antimicrobial activity.

    Science.gov (United States)

    Lucarini, Simone; Fagioli, Laura; Campana, Raffaella; Cole, Hannah; Duranti, Andrea; Baffone, Wally; Vllasaliu, Driton; Casettari, Luca

    2016-10-01

    Sugar based surfactants conjugated with fatty acid chains are an emerging broad group of highly biocompatible and biodegradable compounds with established and potential future applications in the pharmaceutical, cosmetic and food industries. In this work, we investigated absorption enhancing and antimicrobial properties of disaccharide lactose, monoesterified with unsaturated fatty acids through an enzymatic synthetic approach. After chemical and cytotoxicity characterizations, their permeability enhancing activity was demonstrated using intestinal Caco-2 monolayers through transepithelial electrical resistance (TEER) and permeability studies. The synthesized compounds, namely lactose palmitoleate (URB1076) and lactose nervonate (URB1077), were shown to exhibit antimicrobial activity versus eight pathogenic species belonging to Gram-positive, Gram-negative microorganisms and fungi. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Enhanced venous thrombus resolution in plasminogen activator inhibitor type-2 deficient mice.

    Science.gov (United States)

    Siefert, S A; Chabasse, C; Mukhopadhyay, S; Hoofnagle, M H; Strickland, D K; Sarkar, R; Antalis, T M

    2014-10-01

    The resolution of deep vein thrombosis requires an inflammatory response and mobilization of proteases, such as urokinase-type plasminogen activator (uPA) and matrix metalloproteinases (MMPs), to degrade the thrombus and remodel the injured vein wall. Plasminogen activator inhibitor type 2 (PAI-2) is a serine protease inhibitor (serpin) with unique immunosuppressive and cell survival properties that was originally identified as an inhibitor of uPA. To investigate the role of PAI-2 in venous thrombus formation and resolution. Venous thrombus resolution was compared in wild-type C57BL/6, PAI-2(-/-) , and PAI-1(-/-) mice using the stasis model of deep vein thrombosis. Formed thrombi were harvested, thrombus weights were recorded, and tissue was analyzed for uPA and MMP activities, PAI-1 expression, and the nature of inflammatory cell infiltration. We found that the absence of PAI-2 enhanced venous thrombus resolution, while thrombus formation was unaffected. Enhanced venous thrombus resolution in PAI-2(-/-) mice was associated with increased uPA activity and reduced levels of PAI-1, with no significant effect on MMP-2 and -9 activities. PAI-1 deficiency resulted in an increase in thrombus resolution similar to PAI-2 deficiency, but additionally reduced venous thrombus formation and altered MMP activity. PAI-2-deficient thrombi had increased levels of the neutrophil chemoattractant CXCL2, which was associated with early enhanced neutrophil recruitment. These data identify PAI-2 as a novel regulator of venous thrombus resolution, which modulates several pathways involving both inflammatory and uPA activity mechanisms, distinct from PAI-1. Further examination of these pathways may lead to potential therapeutic prospects in accelerating thrombus resolution. © 2014 International Society on Thrombosis and Haemostasis.

  3. Acetic Acid Causes Endoplasmic Reticulum Stress and Induces the Unfolded Protein Response in Saccharomyces cerevisiae

    Directory of Open Access Journals (Sweden)

    Nozomi Kawazoe

    2017-06-01

    Full Text Available Since acetic acid inhibits the growth and fermentation ability of Saccharomyces cerevisiae, it is one of the practical hindrances to the efficient production of bioethanol from a lignocellulosic biomass. Although extensive information is available on yeast response to acetic acid stress, the involvement of endoplasmic reticulum (ER and unfolded protein response (UPR has not been addressed. We herein demonstrated that acetic acid causes ER stress and induces the UPR. The accumulation of misfolded proteins in the ER and activation of Ire1p and Hac1p, an ER-stress sensor and ER stress-responsive transcription factor, respectively, were induced by a treatment with acetic acid stress (>0.2% v/v. Other monocarboxylic acids such as propionic acid and sorbic acid, but not lactic acid, also induced the UPR. Additionally, ire1Δ and hac1Δ cells were more sensitive to acetic acid than wild-type cells, indicating that activation of the Ire1p-Hac1p pathway is required for maximum tolerance to acetic acid. Furthermore, the combination of mild acetic acid stress (0.1% acetic acid and mild ethanol stress (5% ethanol induced the UPR, whereas neither mild ethanol stress nor mild acetic acid stress individually activated Ire1p, suggesting that ER stress is easily induced in yeast cells during the fermentation process of lignocellulosic hydrolysates. It was possible to avoid the induction of ER stress caused by acetic acid and the combined stress by adjusting extracellular pH.

  4. Robust Identification of Developmentally Active Endothelial Enhancers in Zebrafish Using FANS-Assisted ATAC-Seq.

    Science.gov (United States)

    Quillien, Aurelie; Abdalla, Mary; Yu, Jun; Ou, Jianhong; Zhu, Lihua Julie; Lawson, Nathan D

    2017-07-18

    Identification of tissue-specific and developmentally active enhancers provides insights into mechanisms that control gene expression during embryogenesis. However, robust detection of these regulatory elements remains challenging, especially in vertebrate genomes. Here, we apply fluorescent-activated nuclei sorting (FANS) followed by Assay for Transposase-Accessible Chromatin with high-throughput sequencing (ATAC-seq) to identify developmentally active endothelial enhancers in the zebrafish genome. ATAC-seq of nuclei from Tg(fli1a:egfp) y1 transgenic embryos revealed expected patterns of nucleosomal positioning at transcriptional start sites throughout the genome and association with active histone modifications. Comparison of ATAC-seq from GFP-positive and -negative nuclei identified more than 5,000 open elements specific to endothelial cells. These elements flanked genes functionally important for vascular development and that displayed endothelial-specific gene expression. Importantly, a majority of tested elements drove endothelial gene expression in zebrafish embryos. Thus, FANS-assisted ATAC-seq using transgenic zebrafish embryos provides a robust approach for genome-wide identification of active tissue-specific enhancer elements. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

  5. On the Enhanced Antibacterial Activity of Antibiotics Mixed with Gold Nanoparticles

    Directory of Open Access Journals (Sweden)

    Shantrokha AN

    2009-01-01

    Full Text Available Abstract The bacterial action of gentamicin and that of a mixture of gentamicin and 15-nm colloidal-gold particles onEscherichia coliK12 was examined by the agar-well-diffusion method, enumeration of colony-forming units, and turbidimetry. Addition of gentamicin to colloidal gold changed the gold color and extinction spectrum. Within the experimental errors, there were no significant differences in antibacterial activity between pure gentamicin and its mixture with gold nanoparticles (NPs. Atomic absorption spectroscopy showed that upon application of the gentamicin-particle mixture, there were no gold NPs in the zone of bacterial-growth suppression in agar. Yet, free NPs diffused into the agar. These facts are in conflict with the earlier findings indicating an enhancement of the bacterial activity of similar gentamicin–gold nanoparticle mixtures. The possible causes for these discrepancies are discussed, and the suggestion is made that a necessary condition for enhancement of antibacterial activity is the preparation of stable conjugates of NPs coated with the antibiotic molecules.

  6. Psychosocial Pain Management Moderation: The Limit, Activate, and Enhance Model.

    Science.gov (United States)

    Day, Melissa A; Ehde, Dawn M; Jensen, Mark P

    2015-10-01

    There is a growing emphasis in the pain literature on understanding the following second-order research questions: Why do psychosocial pain treatments work? For whom do various treatments work? This critical review summarizes research that addresses the latter question and proposes a moderation model to help guide future research. A theoretical moderation framework for matching individuals to specific psychosocial pain interventions has been lacking. However, several such frameworks have been proposed in the broad psychotherapy and implementation science literature. Drawing on these theories and adapting them specifically for psychosocial pain treatment, here we propose a Limit, Activate, and Enhance model of pain treatment moderation. This model is unique in that it includes algorithms not only for matching treatments on the basis of patient weaknesses but also for directing patients to interventions that build on their strengths. Critically, this model provides a basis for specific a priori hypothesis generation, and a selection of the possible hypotheses drawn from the model are proposed and discussed. Future research considerations are presented that could refine and expand the model based on theoretically driven empirical evidence. The Limit, Activate, and Enhance model presented here is a theoretically derived framework that provides an a priori basis for hypothesis generation regarding psychosocial pain treatment moderators. The model will advance moderation research via its unique focus on matching patients to specific treatments that (1) limit maladaptive responses, (2) activate adaptive responses, and (3) enhance treatment outcomes based on patient strengths and resources. Copyright © 2015 American Pain Society. Published by Elsevier Inc. All rights reserved.

  7. Networking in Sport Management: Ideas and Activities to Enhance Student Engagement and Career Development

    Directory of Open Access Journals (Sweden)

    Alan S. Kornspan

    2013-01-01

    Full Text Available The primary purpose of this paper is to present information regarding the development of networking skills to enhance the career development of sport management students. Specifically, literature is reviewed which supports the importance of networking in the attainment of employment and career advancement in the sport industry. This is followed by an overview of emerging networking activities that allow opportunities for sport management students to expand their network. Sport industry career fairs and career conferences that students can attend are discussed. Additionally, sport industry professional associations that students can become involved with are presented. This is then followed with information related to the development of sport management clubs and various events that can be promoted to enhance the networking process. Specifically, activities provided by university faculty to enhance the educational experience of sport management students are detailed. Finally, a sample schedule of semester activities focused on student engagement and networking activities is provided.

  8. Photon activation therapy: a Monte Carlo study on dose enhancement by various sources and activation media

    International Nuclear Information System (INIS)

    Bakhshabadi, Mahdi; Ghorbani, Mahdi; Meigooni, Ali Soleimani

    2013-01-01

    In the present study, a number of brachytherapy sources and activation media were simulated using MCNPX code and the results were analyzed based on the dose enhancement factor values. Furthermore, two new brachytherapy sources ( 131 Cs and a hypothetical 170 Tm) were evaluated for their application in photon activation therapy (PAT). 125 I, 103 Pd, 131 Cs and hypothetical 170 Tm brachytherapy sources were simulated in water and their dose rate constant and the radial dose functions were compared with previously published data. The sources were then simulated in a soft tissue phantom which was composed of Ag, I, Pt or Au as activation media uniformly distributed in the tumour volume. These simulations were performed using the MCNPX code, and dose enhancement factor (DEF) was obtained for 7, 18 and 30 mg/ml concentrations of the activation media. Each source, activation medium and concentration was evaluated separately in a separate simulation. The calculated dose rate constant and radial dose functions were in agreement with the published data for the aforementioned sources. The maximum DEF was found to be 5.58 for a combination of the 170 Tm source with 30 mg/ml concentration of I. The DEFs for 131 Cs and 170 Tm sources for all the four activation media were higher than those for other sources and activation media. From this point of view, these two sources can be more useful in photon activation therapy with photon emitter sources. Furthermore, 131 Cs and 170 Tm brachytherapy sources can be proposed as new options for use in the field of PAT.

  9. Origin of Activity and Stability Enhancement for Ag3PO4 Photocatalyst after Calcination

    Directory of Open Access Journals (Sweden)

    Pengyu Dong

    2016-11-01

    Full Text Available Pristine Ag3PO4 microspheres were synthesized by a co-precipitation method, followed by being calcined at different temperatures to obtain a series of calcined Ag3PO4 photocatalysts. This work aims to investigate the origin of activity and stability enhancement for Ag3PO4 photocatalyst after calcination based on the systematical analyses of the structures, morphologies, chemical states of elements, oxygen defects, optical absorption properties, separation and transfer of photogenerated electron-hole pairs, and active species. The results indicate that oxygen vacancies (VO˙˙ are created and metallic silver nanoparticles (Ag NPs are formed by the reaction of partial Ag+ in Ag3PO4 semiconductor with the thermally excited electrons from Ag3PO4 and then deposited on the surface of Ag3PO4 microspheres during the calcination process. Among the calcined Ag3PO4 samples, the Ag3PO4-200 sample exhibits the best photocatalytic activity and greatly enhanced photocatalytic stability for photodegradation of methylene blue (MB solution under visible light irradiation. Oxygen vacancies play a significantly positive role in the enhancement of photocatalytic activity, while metallic Ag has a very important effect on improving the photocatalytic stability. Overall, the present work provides some powerful evidences and a deep understanding on the origin of activity and stability enhancement for the Ag3PO4 photocatalyst after calcination.

  10. Chimeric polypeptides having cellulolytic enhancing activity and polynucleotides encoding same

    Science.gov (United States)

    Wogulis, Mark; Sweeney, Matthew; Heu, Tia

    2017-06-14

    The present invention relates to chimeric GH61 polypeptides having cellulolytic enhancing activity. The present invention also relates to polynucleotides encoding the chimeric GH61 polypeptides; nucleic acid constructs, vectors, and host cells comprising the polynucleotides; and methods of using the chimeric GH61 polypeptides.

  11. Hydrolytic enzyme activity enhanced by Barium supplementation

    Directory of Open Access Journals (Sweden)

    Camilo Muñoz

    2016-10-01

    Full Text Available Hydrolysis of polymers is a first and often limiting step during the degradation of plant residues. Plant biomass is generally a major component of waste residues and a major renewable resource to obtain a variety of secondary products including biofuels. Improving the performance of enzymatic hydrolysis of plant material with minimum costs and limiting the use of additional microbial biomass or hydrolytic enzymes directly influences competitiveness of these green biotechnological processes. In this study, we cloned and expressed a cellulase and two esterases recovered from environmental thermophilic soil bacterial communities and characterize their optimum activity conditions including the effect of several metal ions. Results showed that supplementing these hydrolytic reactions with Barium increases the activity of these extracellular hydrolytic enzymes. This observation represents a simple but major improvement to enhance the efficiency and competitiveness of this process within an increasingly important biotechnological sector.

  12. Sphingosine 1-phosphate receptor activation enhances BMP-2-induced osteoblast differentiation

    International Nuclear Information System (INIS)

    Sato, Chieri; Iwasaki, Tsuyoshi; Kitano, Sachie; Tsunemi, Sachi; Sano, Hajime

    2012-01-01

    Highlights: ► We investigated the role of S1P signaling for osteoblast differentiation. ► Both S1P and FTY enhanced BMP-2-stimulated osteoblast differentiation by C2C12 cells. ► S1P signaling enhanced BMP-2-stimulated Smad and ERK phosphorylation by C2C12 cells. ► MEK/ERK signaling is a pathway underlying S1P signaling for osteoblast differentiation. -- Abstract: We previously demonstrated that sphingosine 1-phosphate (S1P) receptor-mediated signaling induced proliferation and prostaglandin productions by synovial cells from rheumatoid arthritis (RA) patients. In the present study we investigated the role of S1P receptor-mediated signaling for osteoblast differentiation. We investigated osteoblast differentiation using C2C12 myoblasts, a cell line derived from murine satellite cells. Osteoblast differentiation was induced by the treatment of bone morphogenic protein (BMP)-2 in the presence or absence of either S1P or FTY720 (FTY), a high-affinity agonist of S1P receptors. Osteoblast differentiation was determined by osteoblast-specific transcription factor, Runx2 mRNA expression, alkaline phosphatase (ALP) activity and osteocalcin production by the cells. Smad1/5/8 and extracellular signal-regulated kinase (ERK) 1/2 phosphorylation was examined by Western blotting. Osteocalcin production by C2C12 cells were determined by ELISA. Runx2 expression and ALP activity by BMP-2-stimulated C2C12 cells were enhanced by addition of either S1P or FTY. Both S1P and FTY enhanced BMP-2-induced ERK1/2 and Smad1/5/8 phosphorylation. The effect of FTY was stronger than that of S1P. S1P receptor-mediated signaling on osteoblast differentiation was inhibited by addition of mitogen-activated protein kinase/ERK kinase (MEK) 1/2 inhibitor, indicating that the S1P receptor-mediated MEK1/2-ERK1/2 signaling pathway enhanced BMP-2-Smad signaling. These results indicate that S1P receptor-mediated signaling plays a crucial role for osteoblast differentiation.

  13. Daily physical activity enhances resilient resources for symptom management in middle-aged women.

    Science.gov (United States)

    Kishida, Moé; Elavsky, Steriani

    2015-07-01

    The aim of the present study was to evaluate the direct and indirect associations between physical activity and menopausal symptoms. Community-dwelling middle-aged women (N = 103; age range 40-60 years) completed daily Internet surveys at the end of the day and wore an accelerometer for the objective assessment of physical activity for 21-days. 1-1-1 multilevel mediation models were estimated to test whether resilient resources (i.e., positive affect and coping efficacy) mediated the association between physical activity and symptom burden at the between- and within-person level. Analyses demonstrated physical activity had an indirect effect (-0.16) on symptom burden through the enhancement of positive affect at the within-person level (p physical activity on symptom burden at the within-person level was -0.08 (p physical activity may help a woman to cope with her symptoms is through the enhancement of positive affect and coping efficacy on a day-to-day basis. (c) 2015 APA, all rights reserved.

  14. PERSPECTIVE: Electrical activity enhances neuronal survival and regeneration

    Science.gov (United States)

    Corredor, Raul G.; Goldberg, Jeffrey L.

    2009-10-01

    The failure of regeneration in the central nervous system (CNS) remains an enormous scientific and clinical challenge. After injury or in degenerative diseases, neurons in the adult mammalian CNS fail to regrow their axons and reconnect with their normal targets, and furthermore the neurons frequently die and are not normally replaced. While significant progress has been made in understanding the molecular basis for this lack of regenerative ability, a second approach has gained momentum: replacing lost neurons or lost connections with artificial electrical circuits that interface with the nervous system. In the visual system, gene therapy-based 'optogenetics' prostheses represent a competing technology. Now, the two approaches are converging, as recent data suggest that electrical activity itself, via the molecular signaling pathways such activity stimulates, is sufficient to induce neuronal survival and regeneration, particularly in retinal ganglion cells. Here, we review these data, discuss the effects of electrical activity on neurons' molecular signaling pathways and propose specific mechanisms by which exogenous electrical activity may be acting to enhance survival and regeneration.

  15. Differentiation and fiber type-specific activity of a muscle creatine kinase intronic enhancer

    Directory of Open Access Journals (Sweden)

    Tai Phillip WL

    2011-07-01

    Full Text Available Abstract Background Hundreds of genes, including muscle creatine kinase (MCK, are differentially expressed in fast- and slow-twitch muscle fibers, but the fiber type-specific regulatory mechanisms are not well understood. Results Modulatory region 1 (MR1 is a 1-kb regulatory region within MCK intron 1 that is highly active in terminally differentiating skeletal myocytes in vitro. A MCK small intronic enhancer (MCK-SIE containing a paired E-box/myocyte enhancer factor 2 (MEF2 regulatory motif resides within MR1. The SIE's transcriptional activity equals that of the extensively characterized 206-bp MCK 5'-enhancer, but the MCK-SIE is flanked by regions that can repress its activity via the individual and combined effects of about 15 different but highly conserved 9- to 24-bp sequences. ChIP and ChIP-Seq analyses indicate that the SIE and the MCK 5'-enhancer are occupied by MyoD, myogenin and MEF2. Many other E-boxes located within or immediately adjacent to intron 1 are not occupied by MyoD or myogenin. Transgenic analysis of a 6.5-kb MCK genomic fragment containing the 5'-enhancer and proximal promoter plus the 3.2-kb intron 1, with and without MR1, indicates that MR1 is critical for MCK expression in slow- and intermediate-twitch muscle fibers (types I and IIa, respectively, but is not required for expression in fast-twitch muscle fibers (types IIb and IId. Conclusions In this study, we discovered that MR1 is critical for MCK expression in slow- and intermediate-twitch muscle fibers and that MR1's positive transcriptional activity depends on a paired E-box MEF2 site motif within a SIE. This is the first study to delineate the DNA controls for MCK expression in different skeletal muscle fiber types.

  16. The Unfolded Protein Response Is Induced by the Cell Wall Integrity Mitogen-activated Protein Kinase Signaling Cascade and Is Required for Cell Wall Integrity in Saccharomyces cerevisiae

    OpenAIRE

    Scrimale, Thomas; Didone, Louis; de Mesy Bentley, Karen L.; Krysan, Damian J.

    2009-01-01

    The yeast cell wall is an extracellular structure that is dependent on secretory and membrane proteins for its construction. We investigated the role of protein quality control mechanisms in cell wall integrity and found that the unfolded protein response (UPR) and, to a lesser extent, endoplasmic reticulum (ER)-associated degradation (ERAD) pathways are required for proper cell wall construction. Null mutation of IRE1, double mutation of ERAD components (hrd1Δ and ubc7Δ) and ire1Δ, or expres...

  17. Gamma irradiation enhances biological activities of mulberry leaf extract

    International Nuclear Information System (INIS)

    Cho, Byoung-Ok; Che, Denis Nchang; Yin, Hong-Hua; Jang, Seon-Il

    2017-01-01

    The purpose of this study was to investigate the influence of irradiation on the anti-oxidative, anti-inflammatory and whitening effects of mulberry leaf extract. This was done by comparing the phenolic contents; 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging effects; 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonicacid) (ABTS) radical scavenging effects; in vitro tyrosinase inhibitory effects and the production of IL-6, TNF-α, PGE 2 , and NO in lipopolysaccharide-stimulated RAW264.7 macrophages and the production of IL-6 and TNF-α in phorbol 12-myristate 13-acetate plus calcium ionophore A23187-stimulated HMC-1 cells, respectively. The results showed that irradiated mulberry leaf extract possesses more anti-oxidant, anti-inflammatory, and tyrosinase inhibitory activities than their non-irradiated counterpart, probably due to increase in phenolic contents induced by gamma irradiation at dose of 10kGy. This research stresses on the importance of irradiation in functional foods. - Highlights: • Gamma-irradiated mulberry leaf extract enhanced in vitro antioxidant activities. • Gamma-irradiated mulberry leaf extract enhanced in vitro tyrosinase inhibitory effects. • Gamma-irradiated mulberry leaf extract treatment reduced the production of IL-6, TNF-α, PGE 2 , and NO.

  18. Can aquatic worms enhance methane production from waste activated sludge?

    NARCIS (Netherlands)

    Serrano, Antonio; Hendrickx, Tim L.G.; Elissen, Hellen; Laarhoven, Bob; Buisman, Cees J.N.; Temmink, Hardy

    2016-01-01

    Although literature suggests that aquatic worms can help to enhance the methane production from excess activated sludge, clear evidence for this is missing. Therefore, anaerobic digestion tests were performed at 20 and at 30 °C with sludge from a high-loaded membrane bioreactor, the aquatic worm

  19. A calpain-2 selective inhibitor enhances learning & memory by prolonging ERK activation.

    Science.gov (United States)

    Liu, Yan; Wang, Yubin; Zhu, Guoqi; Sun, Jiandong; Bi, Xiaoning; Baudry, Michel

    2016-06-01

    While calpain-1 activation is required for LTP induction by theta burst stimulation (TBS), calpain-2 activation limits its magnitude during the consolidation period. A selective calpain-2 inhibitor applied either before or shortly after TBS enhanced the degree of potentiation. In the present study, we tested whether the selective calpain-2 inhibitor, Z-Leu-Abu-CONH-CH2-C6H3 (3, 5-(OMe)2 (C2I), could enhance learning and memory in wild-type (WT) and calpain-1 knock-out (C1KO) mice. We first showed that C2I could reestablish TBS-LTP in hippocampal slices from C1KO mice, and this effect was blocked by PD98059, an inhibitor of ERK. TBS resulted in PTEN degradation in hippocampal slices from both WT and C1KO mice, and C2I treatment blocked this effect in both mouse genotypes. Systemic injection of C2I 30 min before training in the fear-conditioning paradigm resulted in a biphasic dose-response curve, with low doses enhancing and high doses inhibiting freezing behavior. The difference between the doses needed to enhance and inhibit learning matches the difference in concentrations producing inhibition of calpain-2 and calpain-1. A low dose of C2I also restored normal learning in a novel object recognition task in C1KO mice. Levels of SCOP, a ERK phosphatase known to be cleaved by calpain-1, were decreased in dorsal hippocampus early but not late following training in WT mice; C2I treatment did not affect the early decrease in SCOP levels but prevented its recovery at the later time-point and prolonged ERK activation. The results indicate that calpain-2 activation limits the extent of learning, an effect possibly due to temporal limitation of ERK activation, as a result of SCOP synthesis induced by calpain-2-mediated PTEN degradation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Bioengineered nisin A derivatives with enhanced activity against both Gram positive and Gram negative pathogens.

    Directory of Open Access Journals (Sweden)

    Des Field

    Full Text Available Nisin is a bacteriocin widely utilized in more than 50 countries as a safe and natural antibacterial food preservative. It is the most extensively studied bacteriocin, having undergone decades of bioengineering with a view to improving function and physicochemical properties. The discovery of novel nisin variants with enhanced activity against clinical and foodborne pathogens has recently been described. We screened a randomized bank of nisin A producers and identified a variant with a serine to glycine change at position 29 (S29G, with enhanced efficacy against S. aureus SA113. Using a site-saturation mutagenesis approach we generated three more derivatives (S29A, S29D and S29E with enhanced activity against a range of Gram positive drug resistant clinical, veterinary and food pathogens. In addition, a number of the nisin S29 derivatives displayed superior antimicrobial activity to nisin A when assessed against a range of Gram negative food-associated pathogens, including E. coli, Salmonella enterica serovar Typhimurium and Cronobacter sakazakii. This is the first report of derivatives of nisin, or indeed any lantibiotic, with enhanced antimicrobial activity against both Gram positive and Gram negative bacteria.

  1. Bioengineered Nisin A Derivatives with Enhanced Activity against Both Gram Positive and Gram Negative Pathogens

    Science.gov (United States)

    Field, Des; Begley, Maire; O’Connor, Paula M.; Daly, Karen M.; Hugenholtz, Floor; Cotter, Paul D.; Hill, Colin; Ross, R. Paul

    2012-01-01

    Nisin is a bacteriocin widely utilized in more than 50 countries as a safe and natural antibacterial food preservative. It is the most extensively studied bacteriocin, having undergone decades of bioengineering with a view to improving function and physicochemical properties. The discovery of novel nisin variants with enhanced activity against clinical and foodborne pathogens has recently been described. We screened a randomized bank of nisin A producers and identified a variant with a serine to glycine change at position 29 (S29G), with enhanced efficacy against S. aureus SA113. Using a site-saturation mutagenesis approach we generated three more derivatives (S29A, S29D and S29E) with enhanced activity against a range of Gram positive drug resistant clinical, veterinary and food pathogens. In addition, a number of the nisin S29 derivatives displayed superior antimicrobial activity to nisin A when assessed against a range of Gram negative food-associated pathogens, including E. coli, Salmonella enterica serovar Typhimurium and Cronobacter sakazakii. This is the first report of derivatives of nisin, or indeed any lantibiotic, with enhanced antimicrobial activity against both Gram positive and Gram negative bacteria. PMID:23056510

  2. ER signaling is activated to protect human HaCaT keratinocytes from ER stress induced by environmental doses of UVB

    International Nuclear Information System (INIS)

    Mera, Kentaro; Kawahara, Ko-ichi; Tada, Ko-ichi; Kawai, Kazuhiro; Hashiguchi, Teruto; Maruyama, Ikuro; Kanekura, Takuro

    2010-01-01

    Proteins are folded properly in the endoplasmic reticulum (ER). Various stress such as hypoxia, ischemia and starvation interfere with the ER function, causing ER stress, which is defined by the accumulation of unfolded protein (UP) in the ER. ER stress is prevented by the UP response (UPR) and ER-associated degradation (ERAD). These signaling pathways are activated by three major ER molecules, ATF6, IRE-1 and PERK. Using HaCaT cells, we investigated ER signaling in human keratinocytes irradiated by environmental doses of ultraviolet B (UVB). The expression of Ero1-Lα, an upstream signaling molecule of ER stress, decreased at 1-4 h after 10 mJ/cm 2 irradiation, indicating that the environmental dose of UVB-induced ER stress in HaCaT cells, without growth retardation. Furthermore, expression of intact ATF6 was decreased and it was translocated to the nuclei. The expression of XBP-1, a downstream molecule of IRE-1, which is an ER chaperone whose expression is regulated by XBP-1, and UP ubiquitination were induced by 10 mJ/cm 2 UVB at 4 h. PERK, which regulates apoptosis, was not phosphorylated. Our results demonstrate that UVB irradiation generates UP in HaCaT cells and that the UPR and ERAD systems are activated to protect cells from UVB-induced ER stress. This is the first report to show ER signaling in UVB-irradiated keratinocytes.

  3. Educating Students for a Lifetime of Physical Activity: Enhancing Mindfulness, Motivation, and Meaning.

    Science.gov (United States)

    Ennis, Catherine D

    2017-09-01

    For many years, pedagogical scholars and physical education (PE) teachers have worked to enhance effective teaching and learning environments. Yet for some children, youth, and young adults, many of the benefits associated with a physically active lifestyle remain elusive. Enhancing programming and performance to meet physical activity goals may require moving programs beyond "effective." It will require teachers and program leaders to focus programmatic attention on strategies to actually increase students' out-of-class physical activity behavior. Transformative PE provides physical activity content within a nurturing and motivating environment that can change students' lives. It focuses on PE students' role in cognitive decision making, self-motivation, and their search for personal meaning that can add connection and relevance to physical activities. In this SHAPE America - Society of Health and Physical Educators Research Quarterly for Exercise and Sport Lecture, I have synthesized the research on these topics to emphasize useful findings applicable to teachers' everyday planning and teaching. Using sport, physical activity, dance, and adventure activities as the means to an end for personal and social growth, we can meet our commitment to effective standards-based education while preparing students for a lifetime of physical activity.

  4. MWCNT/CdS hybrid nanocomposite for enhanced photocatalytic activity

    International Nuclear Information System (INIS)

    Chaudhary, Deepti; Khare, Neeraj; Vankar, V. D.

    2016-01-01

    Multi-walled carbon nanotubes (MWCNT)/CdS hybrid nanocomposite were synthesized by one step hydrothermal method. MWCNTs were used as a substrate for the growth of CdS nanoparticles. MWCNT/CdS nanocomposite and pure CdS were characterized by XRD, TEM, UV-vis and photoluminescence spectroscopy. HRTEM study confirms the intimate contact of CdS with MWCNT. The photocatalytic activity of nanocomposite was studied for the degradation of methylene blue dye under UV irradiation. The enhanced photocatalytic activity of MWCNT/CdS nanocomposite as compared to pure CdS has been attributed to reduced recombination of photogenerated charge carriers due to interfacial electron transfer from CdS to MWCNT.

  5. Enhanced Photocatalytic Activity of La3+-Doped TiO2 Nanotubes with Full Wave-Band Absorption

    Science.gov (United States)

    Xia, Minghao; Huang, Lingling; Zhang, Yubo; Wang, Yongqian

    2018-06-01

    TiO2 nanotubes doped with La3+ were synthesized by anodic oxidation method and the photocatalytic activity was detected by photodegrading methylene blue. As-prepared samples improved the absorption of both ultraviolet light and visible light and have a great enhancement on the photocatalytic activity while contrasting with the pristine TiO2 nanotubes. A tentative mechanism for the enhancement of photocatalytic activity with full wave-band absorption is proposed.

  6. 77 FR 25188 - Extension of Agency Information Collection Activity Under OMB Review: Enhanced Security...

    Science.gov (United States)

    2012-04-27

    ... general aviation (GA) aircraft operators who wish to fly into and/or out of Ronald Reagan Washington.... Information Collection Requirement Title: Enhanced Security Procedures at Ronald Reagan Washington National...] Extension of Agency Information Collection Activity Under OMB Review: Enhanced Security Procedures at Ronald...

  7. Ileal Crohn disease: mural microvascularity quantified with contrast-enhanced US correlates with disease activity.

    Science.gov (United States)

    De Franco, Antonio; Di Veronica, Alessandra; Armuzzi, Alessandro; Roberto, Italia; Marzo, Manuela; De Pascalis, Barbara; De Vitis, Italo; Papa, Alfredo; Bock, Enrico; Danza, Francesco M; Bonomo, Lorenzo; Guidi, Luisa

    2012-02-01

    To quantitatively assess microvascular activation in the thickened ileal walls of patients with Crohn disease (CD) by using contrast-enhanced ultrasonography (US) and evaluate its correlation with widely used indexes of CD activity. This prospective study was approved by the ethics committee, and written informed consent was obtained from all patients. The authors examined 54 consecutively enrolled patients (mean age, 35.29 years; age range, 18-69 years; 39 men, 15 women) with endoscopically confirmed CD of the terminal ileum. Ileal wall segments thicker than 3 mm were examined with low-mechanical-index contrast-enhanced US and a second-generation US contrast agent. The authors analyzed software-plotted time-enhancement intensity curves to determine the maximum peak intensity (MPI) and wash-in slope coefficient (β) and evaluated their correlation with (a) the composite index of CD activity (CICDA), (b) the CD activity index (CDAI), and (c) the simplified endoscopic score for CD (SES-CD, evaluated in 37 patients) for the terminal ileum. Statistical analysis was performed with the Mann-Whitney test, Spearman rank test, and receiver operating characteristic (ROC) analysis. MPI and β coefficients were significantly increased in the 36 patients with a CICDA indicative of active disease (P<.0001 for both), the 33 patients with a CDAI of at least 150 (P<.032 and P<.0074, respectively), and the 26 patients with an SES-CD of at least 1 (P<.0001 and P<.002, respectively). ROC analysis revealed accurate identification (compared with CICDA) of active CD with an MPI threshold of 24 video intensity (VI) (sensitivity, 97%; specificity, 83%) and a β coefficient of 4.5 VI/sec (sensitivity, 86%; specificity, 83%). Contrast-enhanced US of the ileal wall is a promising method for objective, reproducible assessment of disease activity in patients with ileal CD. © RSNA, 2011

  8. Activated platelets enhance IL-10 secretion and reduce TNF-α secretion by monocytes

    DEFF Research Database (Denmark)

    Gudbrandsdottir, Sif; Hasselbalch, Hans C; Nielsen, Claus H

    2013-01-01

    ), Escherichia coli LPS, or intact Porphyromonas gingivalis. Addition of platelets activated by thrombin-receptor-activating peptide enhanced IL-10 production induced by LPS (p gingivalis (p ....05), and P. gingivalis (p gingivalis-stimulated cultures (p ... of activated platelets. Adherence of platelets increased TG- and TT-induced IL-10 secretion by monocytes (p gingivalis (p

  9. Morphine withdrawal enhances constitutive μ-opioid receptor activity in the ventral tegmental area.

    Science.gov (United States)

    Meye, Frank J; van Zessen, Ruud; Smidt, Marten P; Adan, Roger A H; Ramakers, Geert M J

    2012-11-14

    μ-Opioid receptors (MORs) in the ventral tegmental area (VTA) are pivotally involved in addictive behavior. While MORs are typically activated by opioids, they can also become constitutively active in the absence of any agonist. In the current study, we present evidence that MOR constitutive activity is highly relevant in the mouse VTA, as it regulates GABAergic input to dopamine neurons. Specifically, suppression of MOR constitutive activity with the inverse agonist KC-2-009 enhanced GABAergic neurotransmission onto VTA dopamine neurons. This inverse agonistic effect was fully blocked by the specific MOR neutral antagonist CTOP, which had no effect on GABAergic transmission itself. We next show that withdrawal from chronic morphine further increases the magnitude of inverse agonistic effects at the MOR, suggesting enhanced MOR constitutive activity. We demonstrate that this increase can be an adaptive response to the detrimental elevation in cAMP levels known to occur during morphine withdrawal. These findings offer important insights in the physiological occurrence and function of MOR constitutive activity, and have important implications for therapeutic strategies aimed at normalizing MOR signaling during addiction and opioid overdose.

  10. The Effect of a Voice Activity Detector on the Speech Enhancement

    DEFF Research Database (Denmark)

    Dau, Torsten; Catic, Jasmina; Buchholz, Jörg

    2010-01-01

    A multimicrophone speech enhancement algorithm for binaural hearing aids that preserves interaural time delays was proposed recently. The algorithm is based on multichannel Wiener filtering and relies on a voice activity detector (VAD) for estimation of second-order statistics. Here, the effect...... of a VAD on the speech enhancement of this algorithm was evaluated using an envelopebased VAD, and the performance was compared to that achieved using an ideal error-free VAD. The performance was considered for stationary directional noise and nonstationary diffuse noise interferers at input SNRs from −10...

  11. Silver enhances antibiotic activity against gram-negative bacteria.

    Science.gov (United States)

    Morones-Ramirez, J Ruben; Winkler, Jonathan A; Spina, Catherine S; Collins, James J

    2013-06-19

    A declining pipeline of clinically useful antibiotics has made it imperative to develop more effective antimicrobial therapies, particularly against difficult-to-treat Gram-negative pathogens. Silver has been used as an antimicrobial since antiquity, yet its mechanism of action remains unclear. We show that silver disrupts multiple bacterial cellular processes, including disulfide bond formation, metabolism, and iron homeostasis. These changes lead to increased production of reactive oxygen species and increased membrane permeability of Gram-negative bacteria that can potentiate the activity of a broad range of antibiotics against Gram-negative bacteria in different metabolic states, as well as restore antibiotic susceptibility to a resistant bacterial strain. We show both in vitro and in a mouse model of urinary tract infection that the ability of silver to induce oxidative stress can be harnessed to potentiate antibiotic activity. Additionally, we demonstrate in vitro and in two different mouse models of peritonitis that silver sensitizes Gram-negative bacteria to the Gram-positive-specific antibiotic vancomycin, thereby expanding the antibacterial spectrum of this drug. Finally, we used silver and antibiotic combinations in vitro to eradicate bacterial persister cells, and show both in vitro and in a mouse biofilm infection model that silver can enhance antibacterial action against bacteria that produce biofilms. This work shows that silver can be used to enhance the action of existing antibiotics against Gram-negative bacteria, thus strengthening the antibiotic arsenal for fighting bacterial infections.

  12. Sphingosine 1-phosphate receptor activation enhances BMP-2-induced osteoblast differentiation

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Chieri [Division of Rheumatology, Department of Internal Medicine, Hyogo College of Medicine, 1-1 Mukogawa-cho, Nishinomiya, Hyogo 663-8501 (Japan); Iwasaki, Tsuyoshi, E-mail: tsuyo-i@huhs.ac.jp [Division of Pharmacotherapy, Department of Pharmacy, School of Pharmacy, Hyogo University of Health Sciences, 1-3-6 Minatojima, Chuo-ku, Kobe 650-8530 (Japan); Kitano, Sachie; Tsunemi, Sachi; Sano, Hajime [Division of Rheumatology, Department of Internal Medicine, Hyogo College of Medicine, 1-1 Mukogawa-cho, Nishinomiya, Hyogo 663-8501 (Japan)

    2012-06-22

    Highlights: Black-Right-Pointing-Pointer We investigated the role of S1P signaling for osteoblast differentiation. Black-Right-Pointing-Pointer Both S1P and FTY enhanced BMP-2-stimulated osteoblast differentiation by C2C12 cells. Black-Right-Pointing-Pointer S1P signaling enhanced BMP-2-stimulated Smad and ERK phosphorylation by C2C12 cells. Black-Right-Pointing-Pointer MEK/ERK signaling is a pathway underlying S1P signaling for osteoblast differentiation. -- Abstract: We previously demonstrated that sphingosine 1-phosphate (S1P) receptor-mediated signaling induced proliferation and prostaglandin productions by synovial cells from rheumatoid arthritis (RA) patients. In the present study we investigated the role of S1P receptor-mediated signaling for osteoblast differentiation. We investigated osteoblast differentiation using C2C12 myoblasts, a cell line derived from murine satellite cells. Osteoblast differentiation was induced by the treatment of bone morphogenic protein (BMP)-2 in the presence or absence of either S1P or FTY720 (FTY), a high-affinity agonist of S1P receptors. Osteoblast differentiation was determined by osteoblast-specific transcription factor, Runx2 mRNA expression, alkaline phosphatase (ALP) activity and osteocalcin production by the cells. Smad1/5/8 and extracellular signal-regulated kinase (ERK) 1/2 phosphorylation was examined by Western blotting. Osteocalcin production by C2C12 cells were determined by ELISA. Runx2 expression and ALP activity by BMP-2-stimulated C2C12 cells were enhanced by addition of either S1P or FTY. Both S1P and FTY enhanced BMP-2-induced ERK1/2 and Smad1/5/8 phosphorylation. The effect of FTY was stronger than that of S1P. S1P receptor-mediated signaling on osteoblast differentiation was inhibited by addition of mitogen-activated protein kinase/ERK kinase (MEK) 1/2 inhibitor, indicating that the S1P receptor-mediated MEK1/2-ERK1/2 signaling pathway enhanced BMP-2-Smad signaling. These results indicate that S1P

  13. Immune suppressor factor confers stromal cell line with enhanced supporting activity for hematopoietic stem cells

    International Nuclear Information System (INIS)

    Nakajima, Hideaki; Shibata, Fumi; Fukuchi, Yumi; Goto-Koshino, Yuko; Ito, Miyuki; Urano, Atsushi; Nakahata, Tatsutoshi; Aburatani, Hiroyuki; Kitamura, Toshio

    2006-01-01

    Immune suppressor factor (ISF) is a subunit of the vacuolar ATPase proton pump. We earlier identified a short form of ISF (ShIF) as a stroma-derived factor that supports cytokine-independent growth of mutant Ba/F3 cells. Here, we report that ISF/ShIF supports self-renewal and expansion of primary hematopoietic stem cells (HSCs). Co-culture of murine bone marrow cells with a stromal cell line overexpressing ISF or ShIF (MS10/ISF or MS10/ShIF) not only enhanced their colony-forming activity and the numbers of long-term culture initiating cells, but also maintained the competitive repopulating activity of HSC. This stem cell supporting activity depended on the proton-transfer function of ISF/ShIF. Gene expression analysis of ISF/ShIF-transfected cell lines revealed down-regulation of secreted frizzled-related protein-1 and tissue inhibitor of metalloproteinase-3, and the restoration of their expressions in MS10/ISF cells partially reversed its enhanced LTC-IC supporting activity to a normal level. These results suggest that ISF/ShIF confers stromal cells with enhanced supporting activities for HSCs by modulating Wnt-activity and the extracellular matrix

  14. Gaming is related to enhanced working memory performance and task-related cortical activity.

    Science.gov (United States)

    Moisala, M; Salmela, V; Hietajärvi, L; Carlson, S; Vuontela, V; Lonka, K; Hakkarainen, K; Salmela-Aro, K; Alho, K

    2017-01-15

    Gaming experience has been suggested to lead to performance enhancements in a wide variety of working memory tasks. Previous studies have, however, mostly focused on adult expert gamers and have not included measurements of both behavioral performance and brain activity. In the current study, 167 adolescents and young adults (aged 13-24 years) with different amounts of gaming experience performed an n-back working memory task with vowels, with the sensory modality of the vowel stream switching between audition and vision at random intervals. We studied the relationship between self-reported daily gaming activity, working memory (n-back) task performance and related brain activity measured using functional magnetic resonance imaging (fMRI). The results revealed that the extent of daily gaming activity was related to enhancements in both performance accuracy and speed during the most demanding (2-back) level of the working memory task. This improved working memory performance was accompanied by enhanced recruitment of a fronto-parietal cortical network, especially the dorsolateral prefrontal cortex. In contrast, during the less demanding (1-back) level of the task, gaming was associated with decreased activity in the same cortical regions. Our results suggest that a greater degree of daily gaming experience is associated with better working memory functioning and task difficulty-dependent modulation in fronto-parietal brain activity already in adolescence and even when non-expert gamers are studied. The direction of causality within this association cannot be inferred with certainty due to the correlational nature of the current study. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Hyperbaric Oxygen Environment Can Enhance Brain Activity and Multitasking Performance

    Directory of Open Access Journals (Sweden)

    Dor Vadas

    2017-09-01

    Full Text Available Background: The Brain uses 20% of the total oxygen supply consumed by the entire body. Even though, <10% of the brain is active at any given time, it utilizes almost all the oxygen delivered. In order to perform complex tasks or more than one task (multitasking, the oxygen supply is shifted from one brain region to another, via blood perfusion modulation. The aim of the present study was to evaluate whether a hyperbaric oxygen (HBO environment, with increased oxygen supply to the brain, will enhance the performance of complex and/or multiple activities.Methods: A prospective, double-blind randomized control, crossover trial including 22 healthy volunteers. Participants were asked to perform a cognitive task, a motor task and a simultaneous cognitive-motor task (multitasking. Participants were randomized to perform the tasks in two environments: (a normobaric air (1 ATA 21% oxygen (b HBO (2 ATA 100% oxygen. Two weeks later participants were crossed to the alternative environment. Blinding of the normobaric environment was achieved in the same chamber with masks on while hyperbaric sensation was simulated by increasing pressure in the first minute and gradually decreasing to normobaric environment prior to tasks performance.Results: Compared to the performance at normobaric conditions, both cognitive and motor single tasks scores were significantly enhanced by HBO environment (p < 0.001 for both. Multitasking performance was also significantly enhanced in HBO environment (p = 0.006 for the cognitive part and p = 0.02 for the motor part.Conclusions: The improvement in performance of both single and multi-tasking while in an HBO environment supports the hypothesis which according to, oxygen is indeed a rate limiting factor for brain activity. Hyperbaric oxygenation can serve as an environment for brain performance. Further studies are needed to evaluate the optimal oxygen levels for maximal brain performance.

  16. Cognitive emotion regulation enhances aversive prediction error activity while reducing emotional responses.

    Science.gov (United States)

    Mulej Bratec, Satja; Xie, Xiyao; Schmid, Gabriele; Doll, Anselm; Schilbach, Leonhard; Zimmer, Claus; Wohlschläger, Afra; Riedl, Valentin; Sorg, Christian

    2015-12-01

    Cognitive emotion regulation is a powerful way of modulating emotional responses. However, despite the vital role of emotions in learning, it is unknown whether the effect of cognitive emotion regulation also extends to the modulation of learning. Computational models indicate prediction error activity, typically observed in the striatum and ventral tegmental area, as a critical neural mechanism involved in associative learning. We used model-based fMRI during aversive conditioning with and without cognitive emotion regulation to test the hypothesis that emotion regulation would affect prediction error-related neural activity in the striatum and ventral tegmental area, reflecting an emotion regulation-related modulation of learning. Our results show that cognitive emotion regulation reduced emotion-related brain activity, but increased prediction error-related activity in a network involving ventral tegmental area, hippocampus, insula and ventral striatum. While the reduction of response activity was related to behavioral measures of emotion regulation success, the enhancement of prediction error-related neural activity was related to learning performance. Furthermore, functional connectivity between the ventral tegmental area and ventrolateral prefrontal cortex, an area involved in regulation, was specifically increased during emotion regulation and likewise related to learning performance. Our data, therefore, provide first-time evidence that beyond reducing emotional responses, cognitive emotion regulation affects learning by enhancing prediction error-related activity, potentially via tegmental dopaminergic pathways. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. Exposure to tributyltin induces endoplasmic reticulum stress and the unfolded protein response in zebrafish.

    Science.gov (United States)

    Komoike, Yuta; Matsuoka, Masato

    2013-10-15

    Tributyltin (TBT) is a major marine contaminant and causes endocrine disruption, hepatotoxicity, immunotoxicity, and neurotoxicity. However, the molecular mechanisms underlying the toxicity of TBT have not been fully elucidated. We examined whether exposure to TBT induces the endoplasmic reticulum (ER) stress response in zebrafish, a model organism. Zebrafish-derived BRF41 fibroblast cells were exposed to 0.5 or 1 μM TBT for 0.5-16 h and subsequently lysed and immunoblotted to detect ER stress-related proteins. Zebrafish embryos, grown until 32 h post fertilization (hpf), were exposed to 1 μM TBT for 16 h and used in whole mount in situ hybridization and immunohistochemistry to visualize the expression of ER chaperones and an ER stress-related apoptosis factor. Exposure of the BRF41 cells to TBT caused phosphorylation of the zebrafish homolog of protein kinase RNA-activated-like ER kinase (PERK), eukaryotic translation initiation factor 2 alpha (eIF2α), and inositol-requiring enzyme 1 (IRE1), characteristic splicing of X-box binding protein 1 (XBP1) mRNA, and enhanced expression of activating transcription factor 4 (ATF4) protein. In TBT-exposed zebrafish embryos, ectopic expression of the gene encoding zebrafish homolog of the 78 kDa glucose-regulating protein (GRP78) and gene encoding CCAAT/enhancer-binding protein homologous protein (CHOP) was detected in the precursors of the neuromast, which is a sensory organ for detecting water flow and vibration. Our in vitro and in vivo studies revealed that exposure of zebrafish to TBT induces the ER stress response via activation of both the PERK-eIF2α and IRE1-XBP1 pathways of the unfolded protein response (UPR) in an organ-specific manner. Copyright © 2013 Elsevier B.V. All rights reserved.

  18. Kaposi's sarcoma-associated herpesvirus-encoded LANA associates with glucocorticoid receptor and enhances its transcriptional activities

    International Nuclear Information System (INIS)

    Togi, Sumihito; Nakasuji, Misa; Muromoto, Ryuta; Ikeda, Osamu; Okabe, Kanako; Kitai, Yuichi; Kon, Shigeyuki; Oritani, Kenji; Matsuda, Tadashi

    2015-01-01

    Kaposi's sarcoma-associated herpesvirus (KSHV)-encoded latency-associated nuclear antigen (LANA), which interacts with cellular proteins, plays a central role in modification of viral and/or cellular gene expression. Here, we show that LANA associates with glucocorticoid receptor (GR), and that LANA enhances the transcriptional activity of GR. Co-immunoprecipitation revealed a physical interaction between LANA and GR in transiently transfected 293T and HeLa cells. In human B-lymphoma cells, LANA overexpression enhanced GR activity and cell growth suppression following glucocorticoid stimulation. Furthermore, confocal microscopy showed that activated GR was bound to LANA and accumulated in the nucleus, leading to an increase in binding of activated GR to the glucocorticoid response element of target genes. Taken together, KSHV-derived LANA acts as a transcriptional co-activator of GR. Our results might suggest a careful use of glucocorticoids in the treatment of patients with KSHV-related malignancies such as Kaposi's sarcoma, primary effusion lymphoma, and multicentric Castleman disease. - Highlights: • KSHV-LANA enhances the transcriptional activity of GR in 293T and HeLa cells. • KSHV-LANA physically associates with GR. • KSHV-LANA enhances GR activation and cell growth suppression in human B-lymphocytes. • KSHV-LANA influences the nuclear retention and DNA binding activity of GR

  19. Kaposi's sarcoma-associated herpesvirus-encoded LANA associates with glucocorticoid receptor and enhances its transcriptional activities

    Energy Technology Data Exchange (ETDEWEB)

    Togi, Sumihito; Nakasuji, Misa; Muromoto, Ryuta; Ikeda, Osamu; Okabe, Kanako; Kitai, Yuichi; Kon, Shigeyuki [Department of Immunology, Graduate School of Pharmaceutical Sciences Hokkaido University, Sapporo 060-0812 (Japan); Oritani, Kenji [Department of Hematology and Oncology, Graduate School of Medicine, Osaka University, 2-2 Yamada-oka, Suita, Osaka 565-0871 (Japan); Matsuda, Tadashi, E-mail: tmatsuda@pharm.hokudai.ac.jp [Department of Immunology, Graduate School of Pharmaceutical Sciences Hokkaido University, Sapporo 060-0812 (Japan)

    2015-07-31

    Kaposi's sarcoma-associated herpesvirus (KSHV)-encoded latency-associated nuclear antigen (LANA), which interacts with cellular proteins, plays a central role in modification of viral and/or cellular gene expression. Here, we show that LANA associates with glucocorticoid receptor (GR), and that LANA enhances the transcriptional activity of GR. Co-immunoprecipitation revealed a physical interaction between LANA and GR in transiently transfected 293T and HeLa cells. In human B-lymphoma cells, LANA overexpression enhanced GR activity and cell growth suppression following glucocorticoid stimulation. Furthermore, confocal microscopy showed that activated GR was bound to LANA and accumulated in the nucleus, leading to an increase in binding of activated GR to the glucocorticoid response element of target genes. Taken together, KSHV-derived LANA acts as a transcriptional co-activator of GR. Our results might suggest a careful use of glucocorticoids in the treatment of patients with KSHV-related malignancies such as Kaposi's sarcoma, primary effusion lymphoma, and multicentric Castleman disease. - Highlights: • KSHV-LANA enhances the transcriptional activity of GR in 293T and HeLa cells. • KSHV-LANA physically associates with GR. • KSHV-LANA enhances GR activation and cell growth suppression in human B-lymphocytes. • KSHV-LANA influences the nuclear retention and DNA binding activity of GR.

  20. Effect of SOCS1 overexpression on RPE cell activation by proinflammatory cytokines.

    Science.gov (United States)

    Bazewicz, Magdalena; Draganova, Dafina; Makhoul, Maya; Chtarto, Abdel; Elmaleh, Valerie; Tenenbaum, Liliane; Caspers, Laure; Bruyns, Catherine; Willermain, François

    2016-09-06

    The purpose of this study was to investigate the in vitro effect of Suppressor Of Cytokine Signaling 1 (SOCS1) overexpression in retinal pigment epithelium (RPE) cells on their activation by pro-inflammatory cytokines IFNγ, TNFα and IL-17. Retinal pigment epithelium cells (ARPE-19) were stably transfected with the control plasmid pIRES2-AcGFP1 or the plasmid pSOCS1-IRES2-AcGFP1. They were stimulated by IFNγ (150ng/ml), TNFα (30ng/ml) or IL-17 (100ng/ml). The levels of SOCS1 mRNA were measured by real-time PCR. Signal Transducer and Activator of Transcription 1 (STAT1) phosphorylation and IκBα expression were analysed by western Blot (WB). IL-8 secretion was analysed by ELISA and expression of MHCII molecules and ICAM-1/CD54 by flow cytometry. Our data show that SOCS1 mRNA overexpression in RPE cells prevents IFNγ-induced SOCS1 mRNA increase and IFNγ-mediated STAT1 phosphorylation. Moreover, SOCS1 overexpression in RPE cells inhibits IFNγ-induced decrease of IL-8 secretion and prevents IFNγ-induced MHC II and ICAM1/CD54 upregulation. However, SOCS1 overexpression does not affect TNFα-induced IκBα degradation nor block TNFα-induced or IL-17-induced IL-8 secretion. On the contrary, IL-17-induced secretion is increased by SOCS1 overexpression. In conclusion, SOCS1 overexpression in RPE cells inhibits some IFNγ-mediated responses that lead to uveitis development. This notion raises the possibility that SOCS1 overexpression could be a novel target for treating non-infectious uveitis. However, some proinflammatory effects of TNFα and IL-17 stimulation on RPE are not blocked by SOCS1 overexpression. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  1. Sensitivity-Enhanced Wearable Active Voiceprint Sensor Based on Cellular Polypropylene Piezoelectret.

    Science.gov (United States)

    Li, Wenbo; Zhao, Sheng; Wu, Nan; Zhong, Junwen; Wang, Bo; Lin, Shizhe; Chen, Shuwen; Yuan, Fang; Jiang, Hulin; Xiao, Yongjun; Hu, Bin; Zhou, Jun

    2017-07-19

    Wearable active sensors have extensive applications in mobile biosensing and human-machine interaction but require good flexibility, high sensitivity, excellent stability, and self-powered feature. In this work, cellular polypropylene (PP) piezoelectret was chosen as the core material of a sensitivity-enhanced wearable active voiceprint sensor (SWAVS) to realize voiceprint recognition. By virtue of the dipole orientation control method, the air layers in the piezoelectret were efficiently utilized, and the current sensitivity was enhanced (from 1.98 pA/Hz to 5.81 pA/Hz at 115 dB). The SWAVS exhibited the superiorities of high sensitivity, accurate frequency response, and excellent stability. The voiceprint recognition system could make correct reactions to human voices by judging both the password and speaker. This study presented a voiceprint sensor with potential applications in noncontact biometric recognition and safety guarantee systems, promoting the progress of wearable sensor networks.

  2. Enhancement of DNA polymerase activity in potato tuber slices

    International Nuclear Information System (INIS)

    Watanabe, Akira; Imaseki, Hidemasa

    1977-01-01

    DNA polymerase was extracted from potato (Soleum tuberosum L.) tuber discs and the temporal correlation of its activity change to DNA synthesis in vivo was examined during aging of the discs. Most of the DNA polymerase was recovered as a bound form in the 18,000 x g precipitate. Reaction with the bound-form enzyme was dependent on the presence of four deoxynucleoside triphosphates, Mg 2+ , and a template. ''Activated'' DNA and heat-denatured DNA, but not native DNA, were utilized as templates. The polymerase activity was sensitive to SH reagents. Fresh discs, which do not synthesize DNA in vivo, contained a significant amount of DNA polymerase and its activity increased linearly with time until 48 hr after slicing and became four times that of fresh discs after 72 hr, whereas the activity of DNA synthesis in vivo increased with time and decreased after reaching a maximum at 30 hr. Cycloheximide inhibited the enhancement of polymerase activity. DNA polymerase from aged and fresh discs had identical requirements for deoxynucleotides and a template in their reactions, sensitivity to SH reagent, and affinity to thymidine triphosphate. (auth.)

  3. Recombinant raccoon pox vaccine protects mice against lethal plague

    Science.gov (United States)

    Osorio, J.E.; Powell, T.D.; Frank, R.S.; Moss, K.; Haanes, E.J.; Smith, S.R.; Rocke, T.E.; Stinchcomb, D.T.

    2003-01-01

    Using a raccoon poxvirus (RCN) expression system, we have developed new recombinant vaccines that can protect mice against lethal plague infection. We tested the effects of a translation enhancer (EMCV-IRES) in combination with a secretory (tPA) signal or secretory (tPA) and membrane anchoring (CHV-gG) signals on in vitro antigen expression of F1 antigen in tissue culture and the induction of antibody responses and protection against Yersinia pestis challenge in mice. The RCN vector successfully expressed the F1 protein of Y. pestis in vitro. In addition, the level of expression was increased by the insertion of the EMCV-IRES and combinations of this and the secretory signal or secretory and anchoring signals. These recombinant viruses generated protective immune responses that resulted in survival of 80% of vaccinated mice upon challenge with Y. pestis. Of the RCN-based vaccines we tested, the RCN-IRES-tPA-YpF1 recombinant construct was the most efficacious. Mice vaccinated with this construct withstood challenge with as many as 1.5 million colony forming units of Y. pestis (7.7×104 LD50). Interestingly, vaccination with F1 fused to the anchoring signal (RCN-IRES-tPA-YpF1-gG) elicited significant anti-F1 antibody titers, but failed to protect mice from plague challenge. Our studies demonstrate, in vitro and in vivo, the potential importance of the EMCV-IRES and secretory signals in vaccine design. These molecular tools provide a new approach for improving the efficacy of vaccines. In addition, these novel recombinant vaccines could have human, veterinary, and wildlife applications in the prevention of plague.

  4. The influence of adsorption capacity on enhanced gas absorption in activated carbon slurries

    NARCIS (Netherlands)

    Holstvoogd, R.D.; van Swaaij, Willibrordus Petrus Maria

    1990-01-01

    The enhanced absorption of gases in aqueous activated carbbon slurries of fine particles is studied with a non-steady-state absorption model, taking into account the finite adsorption capacity of the carbon particles. It has been found that, for the different gas/activated carbon slurry systems

  5. Phanerochaete mutants with enhanced ligninolytic activity

    International Nuclear Information System (INIS)

    Kakar, S.N.; Perez, A.; Gonzales, J.

    1994-01-01

    In addition to lignin, the white rot fungus Phanerochaete chrysosporium has the ability to degrade a wide spectrum of recalcitrant organo pollutants in soils and aqueous media. Most of the organic compounds are degraded under ligninolytic conditions with the involvement of the extracellular enzymes, lignin peroxidases, and manganese-dependent peroxidases, which are produced as secondary metabolites triggered by conditions of nutrient starvation (e.g., nitrogen limitation). The fungus and its enzymes can thus provide alternative technologies for bioremediation, bio pulping, bio bleaching, and other industrial applications. The efficiency and effectiveness of the fungus can be enhanced by increasing production and secretion of the important enzymes in large quantities and as primary metabolites under enriched conditions. One way this can be achieved is through isolation of mutants that are deregulated, or are hyper producers or super secretors of key enzymes under enriched conditions. Through UV-light and γ-ray mutagenesis, we have isolated a variety of mutants, some of which produce key enzymes of the ligninolytic system under high-nitrogen growth conditions. One of the mutants, 76UV, produced 272 U of lignin peroxidases enzyme activity/L after 9 d under high nitrogen (although the parent strain does not produce this enzyme under these conditions). The mutant and the parent strains produced up to 54 and 62 U/L, respectively, of the enzyme activity under low nitrogen growth conditions during this period. In some experiments, the mutant showed 281 U/L of enzyme activity under high nitrogen after 17 d

  6. The utrophin A 5'-UTR drives cap-independent translation exclusively in skeletal muscles of transgenic mice and interacts with eEF1A2.

    Science.gov (United States)

    Miura, P; Coriati, A; Bélanger, G; De Repentigny, Y; Lee, J; Kothary, R; Holcik, M; Jasmin, B J

    2010-04-01

    The molecular mechanisms regulating expression of utrophin A are of therapeutic interest since upregulating its expression at the sarcolemma can compensate for the lack of dystrophin in animal models of Duchenne Muscular Dystrophy (DMD). The 5'-UTR of utrophin A has been previously shown to drive cap-independent internal ribosome entry site (IRES)-mediated translation in response to muscle regeneration and glucocorticoid treatment. To determine whether the utrophin A IRES displays tissue specific activity, we generated transgenic mice harboring control (CMV/betaGAL/CAT) or utrophin A 5'-UTR (CMV/betaGAL/UtrA/CAT) bicistronic reporter transgenes. Examination of multiple tissues from two CMV/betaGAL/UtrA/CAT lines revealed that the utrophin A 5'-UTR drives cap-independent translation of the reporter gene exclusively in skeletal muscles and no other examined tissues. This expression pattern suggested that skeletal muscle-specific factors are involved in IRES-mediated translation of utrophin A. We performed RNA-affinity chromatography experiments combined with mass spectrometry to identify trans-factors that bind the utrophin A 5'-UTR and identified eukaryotic elongation factor 1A2 (eEF1A2). UV-crosslinking experiments confirmed the specificity of this interaction. Regions of the utrophin A 5'-UTR that bound eEF1A2 also mediated cap-independent translation in C2C12 muscle cells. Cultured cells lacking eEF1A2 had reduced IRES activity compared with cells overexpressing eEF1A2. Together, these results suggest an important role for eEF1A2 in driving cap-independent translation of utrophin A in skeletal muscle. The trans-factors and signaling pathways driving skeletal-muscle specific IRES-mediated translation of utrophin A could provide unique targets for developing pharmacological-based DMD therapies.

  7. Identifying intrinsic and extrinsic determinants that regulate internal initiation of translation mediated by the FMR1 5' leader

    Directory of Open Access Journals (Sweden)

    Timmerman Stephanie

    2008-10-01

    Full Text Available Abstract Background Regulating synthesis of the Fragile X gene (FMR1 product, FMRP alters neural plasticity potentially through its role in the microRNA pathway. Cap-dependent translation of the FMR1 mRNA, a process requiring ribosomal scanning through the 5' leader, is likely impeded by the extensive secondary structure generated by the high guanosine/cytosine nucleotide content including the CGG triplet nucleotide repeats in the 5' leader. An alternative mechanism to initiate translation – internal initiation often utilizes secondary structure to recruit the translational machinery. Consequently, studies were undertaken to confirm and extend a previous observation that the FMR1 5' leader contains an internal ribosomal entry site (IRES. Results Cellular transfection of a dicistronic DNA construct containing the FMR1 5' leader inserted into the intercistronic region yielded significant translation of the second cistron, but the FMR1 5' leader was also found to contain a cryptic promoter possibly confounding interpretation of these results. However, transfection of dicistronic and monocistronic RNA ex vivo or in vitro confirmed that the FMR1 5' leader contains an IRES. Moreover, inhibiting cap-dependent translation ex vivo did not affect the expression level of endogenous FMRP indicating a role for IRES-dependent translation of FMR1 mRNA. Analysis of the FMR1 5' leader revealed that the CGG repeats and the 5' end of the leader were vital for internal initiation. Functionally, exposure to potassium chloride or intracellular acidification and addition of polyinosinic:polycytidylic acid as mimics of neural activity and double stranded RNA, respectively, differentially affected FMR1 IRES activity. Conclusion Our results indicate that multiple stimuli influence IRES-dependent translation of the FMR1 mRNA and suggest a functional role for the CGG nucleotide repeats.

  8. Kernel-Based Relevance Analysis with Enhanced Interpretability for Detection of Brain Activity Patterns

    Directory of Open Access Journals (Sweden)

    Andres M. Alvarez-Meza

    2017-10-01

    Full Text Available We introduce Enhanced Kernel-based Relevance Analysis (EKRA that aims to support the automatic identification of brain activity patterns using electroencephalographic recordings. EKRA is a data-driven strategy that incorporates two kernel functions to take advantage of the available joint information, associating neural responses to a given stimulus condition. Regarding this, a Centered Kernel Alignment functional is adjusted to learning the linear projection that best discriminates the input feature set, optimizing the required free parameters automatically. Our approach is carried out in two scenarios: (i feature selection by computing a relevance vector from extracted neural features to facilitating the physiological interpretation of a given brain activity task, and (ii enhanced feature selection to perform an additional transformation of relevant features aiming to improve the overall identification accuracy. Accordingly, we provide an alternative feature relevance analysis strategy that allows improving the system performance while favoring the data interpretability. For the validation purpose, EKRA is tested in two well-known tasks of brain activity: motor imagery discrimination and epileptic seizure detection. The obtained results show that the EKRA approach estimates a relevant representation space extracted from the provided supervised information, emphasizing the salient input features. As a result, our proposal outperforms the state-of-the-art methods regarding brain activity discrimination accuracy with the benefit of enhanced physiological interpretation about the task at hand.

  9. Belgian experience with radiation technologies for sterilization

    International Nuclear Information System (INIS)

    Bonet, H.; Dardenne, P.; Herier, A.

    1998-01-01

    Belgium pioneered in non energetic applications of nuclear science. In 1970, the National Institute for Radioisotopes (IRE) was founded on the ground of the experience acquired at the CEN/SCK, for developing nuclear techniques oriented to the well-being of population. In 1978 IRE started operation of 2 γ-irradiation units with a 2.25 million Ci Co 60 , source having a capacity for sterilization of more than 100 m 3 of product per day. this installation is currently operated by Griffith-Mediris (Group Griffith Micro Science) and has accumulated 20 years of experience for irradiation of foodstuffs, medical appliances and pharmaceuticals. In 1986, IRE was producing radioisotopes from accelerators and joined UCL for founding Ion Beam Applications (IBA) company which shortly became the world leader for design and delivery of cyclotrons. More recently, on the basis of French CEA patent, IBA developed the Rhodotron, an e-beam accelerator, with an X-ray option, which is now facing commercial success i area of ionization of food and medical appliances. IRE developed also expertise for the back-end of these activities i.e. final disposal of radioactive sealed source and dismantling of the installations. (author)

  10. Capacitance enhancement of polyaniline coated curved-graphene supercapacitors in a redox-active electrolyte

    KAUST Repository

    Chen, Wei

    2013-01-01

    We show, for the first time, a redox-active electrolyte in combination with a polyaniline-coated curved graphene active material to achieve significant enhancement in the capacitance (36-92% increase) compared to supercapacitors that lack the redox-active contribution from the electrolyte. The supercapacitors based on the redox-active electrolyte also exhibit excellent rate capability and very long cycling performance (>50 000 cycles). This journal is © The Royal Society of Chemistry.

  11. Oridonin Loaded Solid Lipid Nanoparticles Enhanced Antitumor Activity in MCF-7 Cells

    Directory of Open Access Journals (Sweden)

    Lu Wang

    2014-01-01

    Full Text Available Oridonin (ORI, a famous diterpenoid from Chinese herbal medicine, has drawn rising attention for its remarkable apoptosis and autophagy-inducing activity in human cancer therapy, while clinical application of ORI is limited by its strong hydrophobicity and rapid plasma clearance. The purpose of this study was to evaluate whether the antitumor activity of ORI could be enhanced by loading into solid lipid nanoparticles (SLNs. ORI-loaded SLNs were prepared by hot high pressure homogenization with narrow size distribution and good entrapment efficacy. MTT assay indicated that ORI-loaded SLNs enhanced the inhibition of proliferation against several human cancer cell lines including breast cancer MCF-7 cells, hepatocellular carcinoma HepG 2 cells, and lung carcinoma A549 cells compared with free ORI, while no significant enhancement of toxicity to human mammary epithelial MCF-10A cells was shown. Meanwhile, flow cytometric analysis demonstrated that ORI-SLNs induced more significant cell cycle arrest at S and decreased cell cycle arrest at G1/G0 phase in MCF-7 cells than bulk ORI solution. Hoechst 33342 staining and Annexin V/PI assay indicated that apoptotic rates of cells treated with ORI-loaded SLNs were higher compared with free ORI. In summary, our data indicated that SLNs may be a potential carrier for enhancing the antitumor effect of hydrophobic drug ORI.

  12. Enhanced Multisensory Integration and Motor Reactivation after Active Motor Learning of Audiovisual Associations

    Science.gov (United States)

    Butler, Andrew J.; James, Thomas W.; James, Karin Harman

    2011-01-01

    Everyday experience affords us many opportunities to learn about objects through multiple senses using physical interaction. Previous work has shown that active motor learning of unisensory items enhances memory and leads to the involvement of motor systems during subsequent perception. However, the impact of active motor learning on subsequent…

  13. Activated prostaglandin D2 receptors on macrophages enhance neutrophil recruitment into the lung

    Science.gov (United States)

    Jandl, Katharina; Stacher, Elvira; Bálint, Zoltán; Sturm, Eva Maria; Maric, Jovana; Peinhaupt, Miriam; Luschnig, Petra; Aringer, Ida; Fauland, Alexander; Konya, Viktoria; Dahlen, Sven-Erik; Wheelock, Craig E.; Kratky, Dagmar; Olschewski, Andrea; Marsche, Gunther; Schuligoi, Rufina; Heinemann, Akos

    2016-01-01

    Background Prostaglandin (PG) D2 is an early-phase mediator in inflammation, but its action and the roles of the 2 D-type prostanoid receptors (DPs) DP1 and DP2 (also called chemoattractant receptor–homologous molecule expressed on TH2 cells) in regulating macrophages have not been elucidated to date. Objective We investigated the role of PGD2 receptors on primary human macrophages, as well as primary murine lung macrophages, and their ability to influence neutrophil action in vitro and in vivo. Methods In vitro studies, including migration, Ca2+ flux, and cytokine secretion, were conducted with primary human monocyte-derived macrophages and neutrophils and freshly isolated murine alveolar and pulmonary interstitial macrophages. In vivo pulmonary inflammation was assessed in male BALB/c mice. Results Activation of DP1, DP2, or both receptors on human macrophages induced strong intracellular Ca2+ flux, cytokine release, and migration of macrophages. In a murine model of LPS-induced pulmonary inflammation, activation of each PGD2 receptor resulted in aggravated airway neutrophilia, tissue myeloperoxidase activity, cytokine contents, and decreased lung compliance. Selective depletion of alveolar macrophages abolished the PGD2-enhanced inflammatory response. Activation of PGD2 receptors on human macrophages enhanced the migratory capacity and prolonged the survival of neutrophils in vitro. In human lung tissue specimens both DP1 and DP2 receptors were located on alveolar macrophages along with hematopoietic PGD synthase, the rate-limiting enzyme of PGD2 synthesis. Conclusion For the first time, our results show that PGD2 markedly augments disease activity through its ability to enhance the proinflammatory actions of macrophages and subsequent neutrophil activation. PMID:26792210

  14. Dynamic contrast-enhanced 3-T magnetic resonance imaging: a method for quantifying disease activity in early polyarthritis

    Energy Technology Data Exchange (ETDEWEB)

    Navalho, Marcio [Faculdade de Medicina da Universidade de Lisboa, Rheumatology Research Unit, Instituto de Medicina Molecular, Lisbon (Portugal); Hospital da Luz, Radiology Department, Lisbon (Portugal); Hospital da Luz, Centro de Imagiologia, Lisbon (Portugal); Resende, Catarina [Hospital da Luz, Rheumatology Department, Lisbon (Portugal); Hospital de Santa Maria, Rheumatology Department, Centro Hospitalar de Lisboa Norte, EPE, Lisbon (Portugal); Rodrigues, Ana Maria; Fonseca, Joao Eurico; Canhao, Helena [Faculdade de Medicina da Universidade de Lisboa, Rheumatology Research Unit, Instituto de Medicina Molecular, Lisbon (Portugal); Hospital de Santa Maria, Rheumatology Department, Centro Hospitalar de Lisboa Norte, EPE, Lisbon (Portugal); Gaspar, Augusto [Hospital da Luz, Radiology Department, Lisbon (Portugal); Campos, Jorge [Hospital de Santa Maria, Radiology Department, Centro Hospitalar de Lisboa Norte, EPE, Lisbon (Portugal)

    2012-01-15

    To determine whether measurement of synovial enhancement and thickness quantification parameters with 3.0-Tesla magnetic resonance imaging (3-T MRI) can reliably quantify disease activity in patients with early polyarthritis. Eighteen patients (16 women, 2 men; mean age 46 years) with early polyarthritis with less than 12 months of symptoms were included. MRI examination using 3-T device was performed by a new approach including both wrists and hands simultaneously in the examination field-of-view. MRI scoring of disease activity included quantification of synovial enhancement with simple measurements such as rate of early enhancement (REE; REE{sub 57} = S{sub 57}/S{sub 200}, where S{sub 57} and S{sub 200} are the signal intensities 57 s and 200 s after gadolinium injection) and rate of relative enhancement (RE; RE = S{sub 200} - S{sub 0}). Both wrists and hands were scored according to the Rheumatoid Arthritis MRI Scoring System (RAMRIS) for synovitis. Disease activity was clinically assessed by the 28-joint Disease Activity Score (DAS28). DAS28 score was strongly correlated with RE (r = 0.8331, p < 0.0001), REE (r = 0.8112, p < 0.0001), and RAMRIS score for synovitis (r = 0.7659, p < 0.0002). An REE score above 0.778 accurately identified patients with clinically active disease (sensitivity 92%; specificity 67%; p < 0.05). A statistically significant difference was observed in the RE, REE, and RAMRIS scores for synovitis between patients with active and inactive disease (p < 0.05). Our findings support the use of 3-T dynamic contrast-enhanced MRI for precise quantification of disease activity and for discriminating active disease from inactive disease in early polyarthritis. (orig.)

  15. Modafinil enhances thalamocortical activity by increasing neuronal electrotonic coupling

    Science.gov (United States)

    Urbano, Francisco J.; Leznik, Elena; Llinás, Rodolfo R.

    2007-01-01

    Modafinil (Provigil, Modiodal), an antinarcoleptic and mood-enhancing drug, is shown here to sharpen thalamocortical activity and to increase electrical coupling between cortical interneurons and between nerve cells in the inferior olivary nucleus. After irreversible pharmacological block of connexin permeability (i.e., by using either 18β-glycyrrhetinic derivatives or mefloquine), modafinil restored electrotonic coupling within 30 min. It was further established that this restoration is implemented through a Ca2+/calmodulin protein kinase II-dependent step. PMID:17640897

  16. Using the standard deviation of a region of interest in an image to estimate camera to emitter distance.

    Science.gov (United States)

    Cano-García, Angel E; Lazaro, José Luis; Infante, Arturo; Fernández, Pedro; Pompa-Chacón, Yamilet; Espinoza, Felipe

    2012-01-01

    In this study, a camera to infrared diode (IRED) distance estimation problem was analyzed. The main objective was to define an alternative to measures depth only using the information extracted from pixel grey levels of the IRED image to estimate the distance between the camera and the IRED. In this paper, the standard deviation of the pixel grey level in the region of interest containing the IRED image is proposed as an empirical parameter to define a model for estimating camera to emitter distance. This model includes the camera exposure time, IRED radiant intensity and the distance between the camera and the IRED. An expression for the standard deviation model related to these magnitudes was also derived and calibrated using different images taken under different conditions. From this analysis, we determined the optimum parameters to ensure the best accuracy provided by this alternative. Once the model calibration had been carried out, a differential method to estimate the distance between the camera and the IRED was defined and applied, considering that the camera was aligned with the IRED. The results indicate that this method represents a useful alternative for determining the depth information.

  17. Using the Standard Deviation of a Region of Interest in an Image to Estimate Camera to Emitter Distance

    Directory of Open Access Journals (Sweden)

    Felipe Espinoza

    2012-05-01

    Full Text Available In this study, a camera to infrared diode (IRED distance estimation problem was analyzed. The main objective was to define an alternative to measures depth only using the information extracted from pixel grey levels of the IRED image to estimate the distance between the camera and the IRED. In this paper, the standard deviation of the pixel grey level in the region of interest containing the IRED image is proposed as an empirical parameter to define a model for estimating camera to emitter distance. This model includes the camera exposure time, IRED radiant intensity and the distance between the camera and the IRED. An expression for the standard deviation model related to these magnitudes was also derived and calibrated using different images taken under different conditions. From this analysis, we determined the optimum parameters to ensure the best accuracy provided by this alternative. Once the model calibration had been carried out, a differential method to estimate the distance between the camera and the IRED was defined and applied, considering that the camera was aligned with the IRED. The results indicate that this method represents a useful alternative for determining the depth information.

  18. Cis-regulatory RNA elements that regulate specialized ribosome activity.

    Science.gov (United States)

    Xue, Shifeng; Barna, Maria

    2015-01-01

    Recent evidence has shown that the ribosome itself can play a highly regulatory role in the specialized translation of specific subpools of mRNAs, in particular at the level of ribosomal proteins (RP). However, the mechanism(s) by which this selection takes place has remained poorly understood. In our recent study, we discovered a combination of unique RNA elements in the 5'UTRs of mRNAs that allows for such control by the ribosome. These mRNAs contain a Translation Inhibitory Element (TIE) that inhibits general cap-dependent translation, and an Internal Ribosome Entry Site (IRES) that relies on a specific RP for activation. The unique combination of an inhibitor of general translation and an activator of specialized translation is key to ribosome-mediated control of gene expression. Here we discuss how these RNA regulatory elements provide a new level of control to protein expression and their implications for gene expression, organismal development and evolution.

  19. Building novel Ag/CeO2 heterostructure for enhancing photocatalytic activity

    International Nuclear Information System (INIS)

    Leng, Qiang; Yang, Dezhi; Yang, Qi; Hu, Chenguo; Kang, Yue; Wang, Mingjun; Hashim, Muhammad

    2015-01-01

    Highlights: • Ag nanoparticle is designed to building Schottky heterojunction on CeO 2 nanocube. • The photocatalytic activity of Ag/CeO 2 heterostructure is much enhanced. • 95.33% of MB can be effectively degraded within half an hour. • Ag as acceptor of photoelectrons blocks the recombination of electron–hole pairs. - Abstract: Stable and recyclable photocatalysts with high efficiency to degrade organic contamination are important and widely demanded under the threat of the environment pollution. Ag/CeO 2 heterostructure is designed as a photocatalyst to degrade organic dye under the simulated sunlight. The catalytic activity of CeO 2 nanocubes (NCs) to degrade methylene blue (MB) is obviously enhanced when Ag nanoparticles (NPs) are deposited on the surface of them. The weight ratio of Ag and CeO 2 in forming high efficiency catalyst, the amount of Ag/CeO 2 catalyst used in degradation process, and the dye concentration and pH value of the initial MB solution are examined systematically. 95.33% of MB can be effectively degraded within half an hour when 50 mg of Ag/CeO 2 catalyst in an optimal weight ratio of 1:3, is added to the 100 mL of MB solution (c 0 = 1 × 10 −5 mol L −1 , pH 6.2). The mechanism of the enhanced catalytic activity of Ag/CeO 2 heterostructure is discussed. The photocatalytic degradation rate is found to obey pseudo-first-order kinetics equations according to Langmuir–Hinshelwood model. The intermediate products in different stages during the degradation of MB are analyzed

  20. Microwave activation of palladium nanoparticles for enhanced ethanol electrocatalytic oxidation reaction in alkaline medium

    CSIR Research Space (South Africa)

    Rohwer, MB

    2015-02-01

    Full Text Available in alkaline medium (in terms of high mass activity stability and fast reaction kinetics). The remarkable microwave-induced properties on the Pd catalyst promise to revolutionize the use of microwave for catalyst activation for enhanced heterogeneous catalysis...

  1. HIV-1 transcripts use IRES-initiation under conditions where Cap-dependent translation is restricted by poliovirus 2A protease.

    Directory of Open Access Journals (Sweden)

    Raquel Amorim

    Full Text Available The 30 different species of mRNAs synthesized during the HIV-1 replication cycle are all capped and polyadenilated. Internal ribosome entry sites have been recognized in the 5' untranslated region of some mRNA species of HIV-1, which would contribute to an alternative mechanism of initiation of mRNA translation. However, the Cap-dependent translation is assumed to be the main mechanism driving the initiation of HIV-1 protein synthesis. In this work, we describe a cell system in which lower to higher levels of transient expression of the poliovirus 2A protease strongly inhibited cellular Cap-dependent translation with no toxic effect to the cells during a 72-hour time frame. In this system, the synthesis of HIV-1 proteins was inhibited in a temporal dose-dependent way. Higher levels of 2A protease expression severely inhibited HIV-1 protein synthesis during the first 24 hours of infection consequently inhibiting viral production and infectivity. Intermediate to lower levels of 2A Protease expression caused the inhibition of viral protein synthesis only during the first 48 hours of viral replication. After this period both protein synthesis and viral release were recovered to the control levels. However, the infectivity of viral progeny was still partially inhibited. These results indicate that two mechanisms of mRNA translation initiation contribute to the synthesis of HIV-1 proteins; during the first 24-48 hours of viral replication HIV-1 protein synthesis is strongly dependent on Cap-initiation, while at later time points IRES-driven translation initiation is sufficient to produce high amounts of viral particles.

  2. Enhancement of the antifungal activity of antimicrobial drugs by Eugenia uniflora L.

    Science.gov (United States)

    Santos, Karla K A; Matias, Edinardo F F; Tintino, Saulo R; Souza, Celestina E S; Braga, Maria F B M; Guedes, Gláucia M M; Costa, José G M; Menezes, Irwin R A; Coutinho, Henrique Douglas Melo

    2013-07-01

    Candidiasis is the most frequent infection by opportunistic fungi such as Candida albicans, Candida tropicalis, and Candida krusei. Ethanol extract from Eugenia uniflora was assayed, for its antifungal activity, either alone or combined with four selected chemotherapeutic antimicrobial agents, including anphotericin B, mebendazole, nistatin, and metronidazole against these strains. The obtained results indicated that the association of the extract of E. uniflora to metronidazole showed a potential antifungal activity against C. tropicalis. However, no synergistic activity against the other strains was observed, as observed when the extract was associated with the other, not enhancing their antifungal activity.

  3. Lactic acid bacteria: promising supplements for enhancing the biological activities of kombucha.

    Science.gov (United States)

    Nguyen, Nguyen Khoi; Dong, Ngan Thi Ngoc; Nguyen, Huong Thuy; Le, Phu Hong

    2015-01-01

    Kombucha is sweetened black tea that is fermented by a symbiosis of bacteria and yeast embedded within a cellulose membrane. It is considered a health drink in many countries because it is a rich source of vitamins and may have other health benefits. It has previously been reported that adding lactic acid bacteria (Lactobacillus) strains to kombucha can enhance its biological functions, but in that study only lactic acid bacteria isolated from kefir grains were tested. There are many other natural sources of lactic acid bacteria. In this study, we examined the effects of lactic acid bacteria from various fermented Vietnamese food sources (pickled cabbage, kefir and kombucha) on kombucha's three main biological functions: glucuronic acid production, antibacterial activity and antioxidant ability. Glucuronic acid production was determined by high-performance liquid chromatography-mass spectrometry, antibacterial activity was assessed by the agar-well diffusion method and antioxidant ability was evaluated by determining the 2,2-diphenyl-1-picrylhydrazyl radical scavenging capacity. Four strains of food-borne pathogenic bacteria were used in our antibacterial experiments: Listeria monocytogenes ATCC 19111, Escherichia coli ATCC 8739, Salmonella typhimurium ATCC 14028 and Bacillus cereus ATCC 11778. Our findings showed that lactic acid bacteria strains isolated from kefir are superior to those from other sources for improving glucuronic acid production and enhancing the antibacterial and antioxidant activities of kombucha. This study illustrates the potential of Lactobacillus casei and Lactobacillus plantarum isolated from kefir as biosupplements for enhancing the bioactivities of kombucha.

  4. Dengue virus infection-enhancing antibody activities against Indonesian strains in inhabitants of central Thailand.

    Science.gov (United States)

    Yamanaka, Atsushi; Oddgun, Duangjai; Chantawat, Nantarat; Okabayashi, Tamaki; Ramasoota, Pongrama; Churrotin, Siti; Kotaki, Tomohiro; Kameoka, Masanori; Soegijanto, Soegeng; Konishi, Eiji

    2016-04-01

    Dengue virus (DENV) infection-enhancing antibodies are a hypothetic factor to increase the dengue disease severity. In this study, we investigated the enhancing antibodies against Indonesian strains of DENV-1-4 in 50 healthy inhabitants of central Thailand (Bangkok and Uthai Thani). Indonesia and Thailand have seen the highest dengue incidence in Southeast Asia. The infection history of each subject was estimated by comparing his/her neutralizing antibody titers against prototype DENV-1-4 strains. To resolve the difficulty in obtaining foreign live viruses for use as assay antigens, we used a recombinant system to prepare single-round infectious dengue viral particles based on viral sequence information. Irrespective of the previously infecting serotype(s), most serum samples showed significantly higher enhancement titers against Indonesian DENV-2 strains than against Thai DENV-2 strains, whereas the opposite effect was observed for the DENV-3 strains. Equivalent enhancing activities were observed against both DENV-1 and DENV-4. These results suggest that the genotype has an impact on enhancing antibody activities against DENV-2 and DENV-3, because the predominant circulating genotypes of each serotype differ between Indonesia and Thailand. Copyright © 2015 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

  5. Enhancement of synchronized activity between hippocampal CA1 neurons during initial storage of associative fear memory.

    Science.gov (United States)

    Liu, Yu-Zhang; Wang, Yao; Shen, Weida; Wang, Zhiru

    2017-08-01

    Learning and memory storage requires neuronal plasticity induced in the hippocampus and other related brain areas, and this process is thought to rely on synchronized activity in neural networks. We used paired whole-cell recording in vivo to examine the synchronized activity that was induced in hippocampal CA1 neurons by associative fear learning. We found that both membrane potential synchronization and spike synchronization of CA1 neurons could be transiently enhanced after task learning, as observed on day 1 but not day 5. On day 1 after learning, CA1 neurons showed a decrease in firing threshold and rise times of suprathreshold membrane potential changes as well as an increase in spontaneous firing rates, possibly contributing to the enhancement of spike synchronization. The transient enhancement of CA1 neuronal synchronization may play important roles in the induction of neuronal plasticity for initial storage and consolidation of associative memory. The hippocampus is critical for memory acquisition and consolidation. This function requires activity- and experience-induced neuronal plasticity. It is known that neuronal plasticity is largely dependent on synchronized activity. As has been well characterized, repetitive correlated activity of presynaptic and postsynaptic neurons can lead to long-term modifications at their synapses. Studies on network activity have also suggested that memory processing in the hippocampus may involve learning-induced changes of neuronal synchronization, as observed in vivo between hippocampal CA3 and CA1 networks as well as between the rhinal cortex and the hippocampus. However, further investigation of learning-induced synchronized activity in the hippocampus is needed for a full understanding of hippocampal memory processing. In this study, by performing paired whole-cell recording in vivo on CA1 pyramidal cells (PCs) in anaesthetized adult rats, we examined CA1 neuronal synchronization before and after associative fear

  6. Enhancement of antibacterial activity of ciprofloxacin hydrochloride by complexation with sodium cholate

    Directory of Open Access Journals (Sweden)

    Uduma E. Osonwa

    2017-12-01

    Full Text Available Ciprofloxacin is a broad spectrum bactericidal anti-infective agent of the fluoroquinolones class used in treatment of many bacterial infections. In recent times, there has been increasing resistance to the antibiotic. In this work, we investigated the effect of making an ion- pair complex of Ciprofloxacin – hydrochloride with Sodium cholate on bacterial activity. The optimal ratio of the reactants and pH were determined using UV spectrometry. The complex was characterized by octanol-water partitioning, melting point, and IR spectrometry. The antibacterial activity of the complex was determined against Escherichia coli, Staphylococcus aureus, Klebsiella pneumoniae, and Streptococcus pneumoniae by the agar-well diffusion method. The complex was whitish to off-white in color and crystalline, with a melting point of 238 °C. The stoichiometry of the complex shows a molar ratio of 1:1 of sodium cholate to ciprofloxacin. The best pH for complexation was pH 9. The complex partitioned 3.38 times into octanol than in water. The FTIR revealed interaction between the 4-nitrogen atom in the 7-piperazinyl group of ciprofloxacin and the carbonyl of the cholate. The drug in complex form gave double the antibacterial activity of the uncomplexed drug. This study showed that development of hydrophobic ion pair complex enhances antibacterial activity of ciprofloxacin hydrochloride. Keywords: Ciprofloxacin, Sodium cholate, Ion-pair complex, Antibacterial activity, Enhanced activity

  7. Psychopaths show enhanced amygdala activation during fear conditioning

    Directory of Open Access Journals (Sweden)

    Douglas eSchultz

    2016-03-01

    Full Text Available Psychopathy is a personality disorder characterized by emotional deficits and a failure to inhibit impulsive behavior and is often subdivided into primary and secondary psychopathic subtypes. The maladaptive behavior related to primary psychopathy is thought to reflect constitutional fearlessness, while the problematic behavior related to secondary psychopathy is motivated by other factors. The fearlessness observed in psychopathy has often been interpreted as reflecting a fundamental deficit in amygdala function, and previous studies have provided support for a low-fear model of psychopathy. However, many of these studies fail to use appropriate screening procedures, use liberal inclusion criteria, or have used unconventional approaches to assay amygdala function. We measured brain activity with BOLD imaging in primary and secondary psychopaths and non-psychopathic control subjects during Pavlovian fear conditioning. In contrast to the low-fear model, we observed normal fear expression in primary psychopaths. Psychopaths also displayed greater differential BOLD activity in the amygdala relative to matched controls. Inverse patterns of activity were observed in the anterior cingulate cortex (ACC for primary versus secondary psychopaths. Primary psychopaths exhibited a pattern of activity in the dorsal and ventral ACC consistent with enhanced fear expression, while secondary psychopaths exhibited a pattern of activity in these regions consistent with fear inhibition. These results contradict the low-fear model of psychopathy and suggest that the low fear observed for psychopaths in previous studies may be specific to secondary psychopaths.

  8. Platelets are required for enhanced activation of the endothelium and fibrinogen in a mouse thrombosis model of APS.

    Science.gov (United States)

    Proulle, Valerie; Furie, Richard A; Merrill-Skoloff, Glenn; Furie, Barbara C; Furie, Bruce

    2014-07-24

    Antiphospholipid syndrome (APS) is defined by thrombosis, fetal loss, and the presence of antiphospholipid antibodies, including anti-β2-glycoprotein-1 autoantibodies (anti-β2GP1) that have a direct role in the pathogenesis of thrombosis in vivo. The cellular targets of the anti-β2GP1 autoantibody/β2GP1 complex in vivo were studied using a laser-induced thrombosis model of APS in a live mouse and human anti-β2GP1 autoantibodies affinity-purified from APS patients. Cell binding of fluorescently labeled β2GP1 and anti-β2GP1 autoantibodies revealed their colocalization on the platelet thrombus but not the endothelium. Anti-β2GP1 autoantibodies enhanced platelet activation, monitored by calcium mobilization, and endothelial activation, monitored by intercellular adhesion molecule-1 expression. When eptifibatide was infused to block platelet thrombus formation, enhanced fibrin generation and endothelial cell activation were eliminated. Thus, the anti-β2GP1 autoantibody/β2GP1 complex binds to the thrombus, enhancing platelet activation, and platelet secretion leads to enhanced endothelium activation and fibrin generation. These results lead to a paradigm shift away from the concept that binding of the anti-β2GP1 autoantibody/β2GP1 complex activates both endothelial cells and platelets toward one in which activation of platelets in response to anti-β2GP1 autoantibody/β2GP1 complex binding leads to subsequent enhanced endothelium activation and fibrin generation. © 2014 by The American Society of Hematology.

  9. Phospholipase D2 Enhances Epidermal Growth Factor-Induced Akt Activation in EL4 Lymphoma Cells

    Directory of Open Access Journals (Sweden)

    Manpreet S. Chahal

    2010-07-01

    Full Text Available Phospholipase D2 (PLD2 generates phosphatidic acid through hydrolysis of phosphatidylcholine. PLD2 has been shown to play a role in enhancing tumorigenesis. The epidermal growth factor receptor (EGFR can both activate and interact with PLD2. Murine lymphoma EL4 cells lacking endogenous PLD2 present a unique model to elucidate the role of PLD2 in signal transduction. In the current study, we investigated effects of PLD2 on EGF response. Western blotting and RT-PCR were used to establish that both parental cells and PLD2 transfectants express endogenous EGFR. Levels of EGFR protein are increased in cells expressing active PLD2, as compared to parental cells or cells expressing inactive PLD2. EGF stimulates proliferation of EL4 cells transfected with active PLD2, but not parental cells or cells transfected with inactive PLD2. EGF-mediated proliferation in cells expressing active PLD2 is dependent on the activities of both the EGFR and the PI3K/Akt pathway, as demonstrated by studies using protein kinase inhibitors. EGF-induced invasion through a synthetic extracellular matrix is enhanced in cells expressing active PLD2, as compared to parental cells or cells expressing inactive PLD2. Taken together, the data suggest that PLD2 acts in concert with EGFR to enhance mitogenesis and invasion in lymphoma cells.

  10. Phospholipase D2 Enhances Epidermal Growth Factor-Induced Akt Activation in EL4 Lymphoma Cells.

    Science.gov (United States)

    Chahal, Manpreet S; Brauner, Daniel J; Meier, Kathryn E

    2010-07-02

    Phospholipase D2 (PLD2) generates phosphatidic acid through hydrolysis of phosphatidylcholine. PLD2 has been shown to play a role in enhancing tumorigenesis. The epidermal growth factor receptor (EGFR) can both activate and interact with PLD2. Murine lymphoma EL4 cells lacking endogenous PLD2 present a unique model to elucidate the role of PLD2 in signal transduction. In the current study, we investigated effects of PLD2 on EGF response. Western blotting and RT-PCR were used to establish that both parental cells and PLD2 transfectants express endogenous EGFR. Levels of EGFR protein are increased in cells expressing active PLD2, as compared to parental cells or cells expressing inactive PLD2. EGF stimulates proliferation of EL4 cells transfected with active PLD2, but not parental cells or cells transfected with inactive PLD2. EGF-mediated proliferation in cells expressing active PLD2 is dependent on the activities of both the EGFR and the PI3K/Akt pathway, as demonstrated by studies using protein kinase inhibitors. EGF-induced invasion through a synthetic extracellular matrix is enhanced in cells expressing active PLD2, as compared to parental cells or cells expressing inactive PLD2. Taken together, the data suggest that PLD2 acts in concert with EGFR to enhance mitogenesis and invasion in lymphoma cells.

  11. Enhanced photocatalytic activity of SrTiO3 photocatalyst by topotactic preparation

    Science.gov (United States)

    Cao, Jiafeng; Huang, Xianshan; Liu, Yi; Wu, Jianguang; Ji, Yuexia

    2016-11-01

    Novel SrTiO3 (ST) photocatalysts with different shapes such as plates, rods and cubes were successfully synthesized based on a topotactic approach. The rod-like ST particles formed in situ at the plates show superior photocatalytic activities towards the decomposition of Rhodamine B than the plate-like and the cubic particles under visible-light irradiation, which could be attributed to the crystal orientation exposing highly active sites accompanied by the crystallite growth in molten salt. The results reveal an effective approach for fabrication of novel photocatalysts of perovskite structure with enhanced photocatalytic activities.

  12. The enhanced visible light photocatalytic activity of yttrium-doped BiOBr synthesized via a reactable ionic liquid

    Energy Technology Data Exchange (ETDEWEB)

    He, Minqiang; Li, Weibing [School of Chemistry and Chemical Engineering, Jiangsu University, 301 Xuefu Road, Zhenjiang 212013 (China); Xia, Jiexiang, E-mail: xjx@ujs.edu.cn [School of Chemistry and Chemical Engineering, Jiangsu University, 301 Xuefu Road, Zhenjiang 212013 (China); Xu, Li; Di, Jun [School of Chemistry and Chemical Engineering, Jiangsu University, 301 Xuefu Road, Zhenjiang 212013 (China); Xu, Hui [School of the Environment, Jiangsu University, 301 Xuefu Road, Zhenjiang 212013 (China); Yin, Sheng [School of Chemistry and Chemical Engineering, Jiangsu University, 301 Xuefu Road, Zhenjiang 212013 (China); Li, Huaming, E-mail: lhm@ujs.edu.cn [School of Chemistry and Chemical Engineering, Jiangsu University, 301 Xuefu Road, Zhenjiang 212013 (China); Li, Mengna [School of Chemistry and Chemical Engineering, Jiangsu University, 301 Xuefu Road, Zhenjiang 212013 (China)

    2015-03-15

    Graphical abstract: Yttrium (Y)-doped BiOBr with different Y doping concentrations has been synthesized via solvothermal method in the presence of reactable ionic liquid 1-hexadecyl-3-methylimidazolium bromide ([C16mim]Br). The photocatalytic activities of the yttrium doped BiOBr samples were evaluated by the degradation of ciprofloxacin (CIP) and rhodamine B (RhB) under visible-light irradiation. The yttrium doped BiOBr exhibited enhanced photocatalytic activity for the degradation of the two types of pollutants, and the 5wt%Y-doped BiOBr showed the highest photocatalytic activity. The enhanced photocatalytic performance could be attributed to the reduced band gap and improved separation of electron–hole pairs. - Highlights: • Yttrium (Y)-doped BiOBr composites have been synthesized via solvothermal method in the presence of reactable ionic liquid [C16mim]Br. • The yttrium doped BiOBr exhibited enhanced photocatalytic activity for the degradation of ciprofloxacin (CIP) and rhodamine B (RhB). • The enhanced photocatalytic performance could be attributed to the reduced band gap and improved separation of electron–hole pairs. - Abstract: Yttrium (Y)-doped BiOBr with different Y doping concentrations has been synthesized via solvothermal method in the presence of reactable ionic liquid 1-hexadecyl-3-methylimidazolium bromide ([C{sub 16}mim]Br). Their structures, morphologies and optical properties were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS) and UV–vis diffuse reflectance spectroscopy (DRS). The photocatalytic activities of the yttrium doped BiOBr samples were evaluated by the degradation of ciprofloxacin (CIP) and rhodamine B (RhB) under visible-light irradiation. The yttrium doped BiOBr exhibited enhanced photocatalytic activity for the degradation of the two types of pollutants, and the 5wt%Y-doped BiOBr showed the highest

  13. Transport activity of the sodium bicarbonate cotransporter NBCe1 is enhanced by different isoforms of carbonic anhydrase.

    Directory of Open Access Journals (Sweden)

    Christina Schueler

    Full Text Available Transport metabolons have been discussed between carbonic anhydrase II (CAII and several membrane transporters. We have now studied different CA isoforms, expressed in Xenopus oocytes alone and together with the electrogenic sodium bicarbonate cotransporter 1 (NBCe1, to determine their catalytic activity and their ability to enhance NBCe1 transport activity. pH measurements in intact oocytes indicated similar activity of CAI, CAII and CAIII, while in vitro CAIII had no measurable activity and CAI only 30% of the activity of CAII. All three CA isoforms increased transport activity of NBCe1, as measured by the transport current and the rate of intracellular sodium rise in oocytes. Two CAII mutants, altered in their intramolecular proton pathway, CAII-H64A and CAII-Y7F, showed significant catalytic activity and also enhanced NBCe1 transport activity. The effect of CAI, CAII, and CAII mutants on NBCe1 activity could be reversed by blocking CA activity with ethoxyzolamide (EZA, 10 µM, while the effect of the less EZA-sensitive CAIII was not reversed. Our results indicate that different CA isoforms and mutants, even if they show little enzymatic activity in vitro, may display significant catalytic activity in intact cells, and that the ability of CA to enhance NBCe1 transport appears to depend primarily on its catalytic activity.

  14. Irreversible electroporation of the pancreas is feasible and safe in a porcine survival model.

    Science.gov (United States)

    Fritz, Stefan; Sommer, Christof M; Vollherbst, Dominik; Wachter, Miguel F; Longerich, Thomas; Sachsenmeier, Milena; Knapp, Jürgen; Radeleff, Boris A; Werner, Jens

    2015-07-01

    Use of thermal tumor ablation in the pancreatic parenchyma is limited because of the risk of pancreatitis, pancreatic fistula, or hemorrhage. This study aimed to evaluate the feasibility and safety of irreversible electroporation (IRE) in a porcine model. Ten pigs were divided into 2 study groups. In the first group, animals received IRE of the pancreatic tail and were killed after 60 minutes. In the second group, animals received IRE at the head of the pancreas and were followed up for 7 days. Clinical parameters, computed tomography imaging, laboratory results, and histology were obtained. All animals survived IRE ablation, and no cardiac adverse effects were noted. Sixty minutes after IRE, a hypodense lesion on computed tomography imaging indicated the ablation zone. None of the animals developed clinical signs of acute pancreatitis. Only small amounts of ascites fluid, with a transient increase in amylase and lipase levels, were observed, indicating that no pancreatic fistula occurred. This porcine model shows that IRE is feasible and safe in the pancreatic parenchyma. Computed tomography imaging reveals significant changes at 60 minutes after IRE and therefore might serve as an early indicator of therapeutic success. Clinical studies are needed to evaluate the efficacy of IRE in pancreatic cancer.

  15. Enhancement of antioxidant activity of C-phycocyanin of Spirulina powder treated with supercritical fluid carbon dioxide

    Directory of Open Access Journals (Sweden)

    Monchai Dejsungkranont

    2017-10-01

    Full Text Available The functionality and activity of proteins can be modified by supercritical fluid CO2 (SCFCO2. The objectives of this study were to investigate the possibility of enhanced antioxidant activity of C-phycocyanin (C-PC proteins from light-harvested Spirulina maxima powder using the SCFCO2 pretreatment and to optimize the SCFCO2 pretreatment conditions enhancing the antioxidant activity of C-PC. The Taguchi method was used to determine the optimum conditions for the SCFCO2 pretreatment. The experimental factors were the pretreatment temperature, pressure, pretreatment mode (static, dynamic and conjugated and duration. The optimal conditions of SCFCO2 pretreatment were: 60 °C, 24.13 MPa and 60 min in static batch mode. Using these pretreatment conditions, the maximum antioxidant activity of C-PC from the treated residual biomass was 410.1 μmole trolox/mg, which was 1.7-fold higher than the untreated biomass (control. The factor that most affected the antioxidant activity of C-PC was temperature (59%. A high pretreatment temperature could damage C-PC, but promoted antioxidant activity. Of note is that this work was the first to explore SCFCO2 treatment enhancing the antioxidant activity of C-PC in Spirulina sp. powder. Keywords: Antioxidant activity, C-phycocyanin, Spirulina sp., Supercritical fluid carbon dioxide pretreatment, Taguchi method

  16. Exposure to 4-tert-octylphenol, an environmentally persistent alkylphenol, enhances interleukin-4 production in T cells via NF-AT activation

    International Nuclear Information System (INIS)

    Lee, Mi H.; Kim, Eugene; Kim, Tae S.

    2004-01-01

    4-tert-Octylphenol (OP) is a representative endocrine disruptor that may have adverse effects on human health. The influence of this compound on allergic immune responses remains unclear. In this study, we have examined the effects of OP on production of interleukin-4 (IL-4), a pro-inflammatory cytokine closely associated with allergic immune responses. OP significantly enhanced IL-4 production in antigen-primed T cells in a dose-dependent manner. Treatment with OP in vivo resulted in significant increase of IL-4 production in T cells and of IgE levels in sera of antigen-primed mice. Furthermore, OP enhanced the activation of IL-4 gene promoter in EL4 T cells transiently transfected with IL-4 promoter/reporter constructs, and the enhancing effect mapped to a region in the IL-4 promoter containing binding sites for nuclear factor of activated T cell (NF-AT). Activation of T cells by phorbol-12-myristate-13-acetate (PMA) resulted in markedly enhanced binding activities to the NF-AT site, which significantly increased upon addition of OP, indicating that the transcription factor NF-AT was involved in the enhancing effect of OP on IL-4 production. The enhancement of IL-4 production by OP was blocked by FK506, a calcineurin inhibitor, but not by the estrogen receptor (ER) antagonist ICI 182 780. FK506 inhibited the NF-AT-DNA binding activity and IL-4 gene promoter activity enhanced by OP in a dose-dependent manner. These findings demonstrate that OP enhances IL-4 production in T cells via the stimulation of calcineurin-dependent NF-AT activation

  17. The interaction between the iron-responsive element binding protein and its cognate RNA is highly dependent upon both RNA sequence and structure.

    Science.gov (United States)

    Jaffrey, S R; Haile, D J; Klausner, R D; Harford, J B

    1993-09-25

    To assess the influence of RNA sequence/structure on the interaction RNAs with the iron-responsive element binding protein (IRE-BP), twenty eight altered RNAs were tested as competitors for an RNA corresponding to the ferritin H chain IRE. All changes in the loop of the predicted IRE hairpin and in the unpaired cytosine residue characteristically found in IRE stems significantly decreased the apparent affinity of the RNA for the IRE-BP. Similarly, alteration in the spacing and/or orientation of the loop and the unpaired cytosine of the stem by either increasing or decreasing the number of base pairs separating them significantly reduced efficacy as a competitor. It is inferred that the IRE-BP forms multiple contacts with its cognate RNA, and that these contacts, acting in concert, provide the basis for the high affinity of this interaction.

  18. Fingolimod in active multiple sclerosis: an impressive decrease in Gd-enhancing lesions

    NARCIS (Netherlands)

    Muris, A.H.; Rolf, L.; Damoiseaux, J.; Koeman, E.; Hupperts, R.

    2014-01-01

    Background: Fingolimod is a disease modifying therapy (DMT) in highly active relapsing remitting multiple sclerosis (RRMS), as is natalizumab. Fingolimod decreases annual relapse rates and gadolinium enhancing lesions on MRI as compared to either interferon beta (IFNβ) or placebo. The effect of

  19. Glutamate transporter activity promotes enhanced Na+/K+-ATPase -mediated extracellular K+ management during neuronal activity

    DEFF Research Database (Denmark)

    Larsen, Brian R; Holm, Rikke; Vilsen, Bente

    2016-01-01

    , in addition, Na+ /K+ -ATPase-mediated K+ clearance could be governed by astrocytic [Na+ ]i . During most neuronal activity, glutamate is released in the synaptic cleft and is re-absorbed by astrocytic Na+ -coupled glutamate transporters, thereby elevating [Na+ ]i . It thus remains unresolved whether...... the different Na+ /K+ -ATPase isoforms are controlled by [K+ ]o or [Na+ ]i during neuronal activity. Hippocampal slice recordings of stimulus-induced [K+ ]o transients with ion-sensitive microelectrodes revealed reduced Na+ /K+ -ATPase-mediated K+ management upon parallel inhibition of the glutamate transporter......+ affinity to the α1 and α2 isoforms than the β2 isoform. In summary, enhanced astrocytic Na+ /K+ -ATPase-dependent K+ clearance was obtained with parallel glutamate transport activity. The astrocytic Na+ /K+ -ATPase isoform constellation α2β1 appeared to be specifically geared to respond to the [Na+ ]i...

  20. Hyperbaric Oxygen Environment Can Enhance Brain Activity and Multitasking Performance.

    Science.gov (United States)

    Vadas, Dor; Kalichman, Leonid; Hadanny, Amir; Efrati, Shai

    2017-01-01

    Background: The Brain uses 20% of the total oxygen supply consumed by the entire body. Even though, multitasking), the oxygen supply is shifted from one brain region to another, via blood perfusion modulation. The aim of the present study was to evaluate whether a hyperbaric oxygen (HBO) environment, with increased oxygen supply to the brain, will enhance the performance of complex and/or multiple activities. Methods: A prospective, double-blind randomized control, crossover trial including 22 healthy volunteers. Participants were asked to perform a cognitive task, a motor task and a simultaneous cognitive-motor task (multitasking). Participants were randomized to perform the tasks in two environments: (a) normobaric air (1 ATA 21% oxygen) (b) HBO (2 ATA 100% oxygen). Two weeks later participants were crossed to the alternative environment. Blinding of the normobaric environment was achieved in the same chamber with masks on while hyperbaric sensation was simulated by increasing pressure in the first minute and gradually decreasing to normobaric environment prior to tasks performance. Results: Compared to the performance at normobaric conditions, both cognitive and motor single tasks scores were significantly enhanced by HBO environment ( p Multitasking performance was also significantly enhanced in HBO environment ( p = 0.006 for the cognitive part and p = 0.02 for the motor part). Conclusions: The improvement in performance of both single and multi-tasking while in an HBO environment supports the hypothesis which according to, oxygen is indeed a rate limiting factor for brain activity. Hyperbaric oxygenation can serve as an environment for brain performance. Further studies are needed to evaluate the optimal oxygen levels for maximal brain performance.

  1. Niclosamide enhances ROS-mediated cell death through c-Jun activation.

    Science.gov (United States)

    Lee, Sae-lo-oom; Son, A-Rang; Ahn, Jiyeon; Song, Jie-Young

    2014-06-01

    Radiotherapy is an effective treatment modality in the clinical treatment of cancers, and has been combined with chemotherapy in order to improve therapeutic efficacy. Therefore, we aimed to develop small molecules that enhance the cytotoxic effects of radiotherapy. In this study, we provide evidence that niclosamide is an effective radiosensitizer in non-small cell lung cancer cells. Using a cell-based high-throughput viability screen of 1040 compounds in combination with γ-ionizing radiation (IR), we found niclosamide, an FDA-approved antihelminthic agent, had a radiosensitizing effect on H1299 human lung cancer cells. Pretreatment with niclosamide enhanced IR- induced cell death of H1299 in a dose-dependent manner via apoptosis compared with IR or niclosamide alone. The combined treatment induced significantly more phosphorylation of p38 MAPK and c-Jun in H1299 cells than IR or niclosamide alone. Since IR induces apoptosis through generation of reactive oxygen species (ROS), hydrogen peroxide (H2O2) was employed as another ROS generator and we found that niclosamide also sensitized cells to H2O2. Niclosamide pretreatment also induced c-Jun and its phosphorylation in the presence of H2O2, thereby enhancing apoptosis. N-acetyl-L-cysteine (NAC) treatment abolished both cell death and c-Jun activation induced by the combination treatments. Knockdown of c-Jun also decreased PARP cleavage and clonogenic cell survival in niclosamide- and IR-treated H1299 cells. Our findings suggest that niclosamide could be a promising radiosensitizer in lung cancer patients through activation of the p38 MAPK-c-Jun axis. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  2. Study on CO{sub 2} absorption enhancement by adding active carbon particles into MEA solution

    Energy Technology Data Exchange (ETDEWEB)

    Qian, Juan; Sun, Rui; Ma, Lian; Sun, Shaozeng [Harbin Institute of Technology, Harbin (China). School of Energy Science and Engineering

    2013-07-01

    The chemical absorption of CO{sub 2} is generally recognized as the most efficient post-combustion technology of CO{sub 2} separation at present. A study on CO{sub 2} absorption enhancement by adding small particles of active carbon into MEA solution is investigated within a self-designed glass stirring tank. Experiments of different particle loadings and different particle sizes have been conducted. When active carbon particle concentration is fewer, compared to the absorption rate of CO{sub 2} gas absorbed by MEA aqueous solution, the role of active carbon adsorption CO{sub 2} gas is negligible. The enhancement efficiency of CO{sub 2} absorption could be improved by 10% to the upmost in this liquid-particle system.

  3. Select polyphenolic fractions from dried plum enhance osteoblast activity through BMP-2 signaling.

    Science.gov (United States)

    Graef, Jennifer L; Rendina-Ruedy, Elizabeth; Crockett, Erica K; Ouyang, Ping; King, Jarrod B; Cichewicz, Robert H; Lucas, Edralin A; Smith, Brenda J

    2018-05-01

    Dried plum supplementation has been shown to enhance bone formation while suppressing bone resorption. Evidence from previous studies has demonstrated that these responses can be attributed in part to the fruit's polyphenolic compounds. The purpose of this study was to identify the most bioactive polyphenolic fractions of dried plum with a focus on their osteogenic activity and to investigate their mechanisms of action under normal and inflammatory conditions. Utilizing chromatographic techniques, six fractions of polyphenolic compounds were prepared from a crude extract of dried plum. Initial screening assays revealed that two fractions (DP-FrA and DP-FrB) had the greatest osteogenic potential. Subsequent experiments using primary bone-marrow-derived osteoblast cultures demonstrated these two fractions enhanced extracellular alkaline phosphatase (ALP), an indicator of osteoblast activity, and mineralized nodule formation under normal conditions. Both fractions enhanced bone morphogenetic protein (BMP) signaling, as indicated by increased Bmp2 and Runx2 gene expression and protein levels of phosphorylated Smad1/5. DP-FrB was most effective at up-regulating Tak1 and Smad1, as well as protein levels of phospho-p38. Under inflammatory conditions, TNF-α suppressed ALP and tended to decrease nodule formation (P=.0674). This response coincided with suppressed gene expression of Bmp2 and the up-regulation of Smad6, an inhibitor of BMP signaling. DP-FrA and DP-FrB partially normalized these responses. Our results show that certain fractions of polyphenolic compounds in dried plum up-regulate osteoblast activity by enhancing BMP signaling, and when this pathway is inhibited by TNF-α, the osteogenic response is attenuated. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Hydrogen adsorption-mediated synthesis of concave Pt nanocubes and their enhanced electrocatalytic activity

    Science.gov (United States)

    Lu, Bang-An; Du, Jia-Huan; Sheng, Tian; Tian, Na; Xiao, Jing; Liu, Li; Xu, Bin-Bin; Zhou, Zhi-You; Sun, Shi-Gang

    2016-06-01

    Concave nanocubes are enclosed by high-index facets and have negative curvature; they are expected to have enhanced reactivity, as compared to nanocubes with flat surfaces. Herein, we propose and demonstrate a new strategy for the synthesis of concave Pt nanocubes with {hk0} high-index facets, by using a hydrogen adsorption-mediated electrochemical square-wave potential method. It was found that Pt atoms prefer to deposit on edge sites rather than terrace sites on Pt surfaces with intensive hydrogen adsorption, resulting in the formation of concave structures. The as-prepared concave Pt nanocubes exhibit enhanced catalytic activity and stability towards oxidation of ethanol and formic acid in acidic solutions, compared to commercial Pt/C catalysts.Concave nanocubes are enclosed by high-index facets and have negative curvature; they are expected to have enhanced reactivity, as compared to nanocubes with flat surfaces. Herein, we propose and demonstrate a new strategy for the synthesis of concave Pt nanocubes with {hk0} high-index facets, by using a hydrogen adsorption-mediated electrochemical square-wave potential method. It was found that Pt atoms prefer to deposit on edge sites rather than terrace sites on Pt surfaces with intensive hydrogen adsorption, resulting in the formation of concave structures. The as-prepared concave Pt nanocubes exhibit enhanced catalytic activity and stability towards oxidation of ethanol and formic acid in acidic solutions, compared to commercial Pt/C catalysts. Electronic supplementary information (ESI) available: Details of DFT calculation, SEM images of concave Pt nanocubes, mass activity and stability characterization of the catalysts. See DOI: 10.1039/c6nr02349e

  5. Enhancement mechanisms of short-time aerobic digestion for waste activated sludge in the presence of cocoamidopropyl betaine.

    Science.gov (United States)

    Xia, Siqing; Zhou, Yun; Eustance, Everett; Zhang, Zhiqiang

    2017-10-18

    Cocoamidopropyl betaine (CAPB), which is a biodegradable ampholytic surfactant, has recently been found to dramatically enhance the aerobic digestion of waste activated sludge (WAS) in short-time aerobic digestion (STAD) systems. Therefore, it is important to understand the mechanisms in which CAPB enhances WAS aerobic digestion performance. Results showed that CAPB could dramatically enhance the solubilization of soluble proteins (PN), polysaccharides (PS), nucleic acids (NA) and humic-like substances (HS) in the STAD system within the initial 2 h. Then PN, PS and NA gradually decreased, while HS showed only minor decease. In addition, CAPB increased the proportion of low MW fractions (biodegradable. Specific oxygen uptake rates and dehydrogenase enzyme activity results indicated that CAPB markedly improved the aerobic microorganism activities. Microbial community analyses and principle coordinate analyses (PCoA) revealed that CAPB increased the proportion of some functional microorganisms, including Proteobacteria, Planctomycetales, Acinetobacter, Pseudomonas and Aeromonas. The changes driven by CAPB could explain the enhanced performance of the STAD system for WAS aerobic treatment.

  6. Translational Control in Bone Marrow Failure

    Science.gov (United States)

    2016-07-01

    2014). 2d. Prepare vectors containing mutations for IRES test assay (months 3-9). Vectors for IRES test assay were prepared as described in the...Materials and Methods section of Tidwell et al. 2014. 2e. Develop IRES test assay in HeLa cells (months 9-12). We developed an IRES test assay system...Pathogenesis of ELANE-related neutropenia). 11 6. PUBLICATIONS, ABSTRACTS, AND PRESENTATIONS a. Manuscripts Tidwell, T., Wechsler , J., Nayak

  7. Zero-valent iron enhanced methanogenic activity in anaerobic digestion of waste activated sludge after heat and alkali pretreatment.

    Science.gov (United States)

    Zhang, Yaobin; Feng, Yinghong; Quan, Xie

    2015-04-01

    Heat or alkali pretreatment is the effective method to improve hydrolysis of waste sludge and then enhance anaerobic sludge digestion. However the pretreatment may inactivate the methanogens in the sludge. In the present work, zero-valent iron (ZVI) was used to enhance the methanogenic activity in anaerobic sludge digester under two methanogens-suppressing conditions, i.e. heat-pretreatment and alkali condition respectively. With the addition of ZVI, the lag time of methane production was shortened, and the methane yield increased by 91.5% compared to the control group. The consumption of VFA was accelerated by ZVI, especially for acetate, indicating that the acetoclastic methanogenesis was enhanced. In the alkali-condition experiment, the hydrogen produced decreased from 27.6 to 18.8 mL when increasing the ZVI dosage from 0 to 10 g/L. Correspondingly, the methane yield increased from 1.9 to 32.2 mL, which meant that the H2-utilizing methanogenes was enriched. These results suggested that the addition of ZVI into anaerobic digestion of sludge after pretreated by the heat or alkali process could efficiently recover the methanogenic activity and increase the methane production and sludge reduction. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Biomonitoring of intermittent rivers and ephemeral streams in Europe

    NARCIS (Netherlands)

    Stubbington, Rachel; Chadd, Richard; Cid, Núria; Csabai, Zoltán; Miliša, Marko; Morais, Manuela; Munné, Antoni; Pařil, Petr; Pešić, Vladimir; Tziortzis, Iakovos; Verdonschot, Ralf C.M.; Datry, Thibault

    2018-01-01

    Intermittent rivers and ephemeral streams (IRES) are common across Europe and dominate some Mediterranean river networks. In all climate zones, IRES support high biodiversity and provide ecosystem services. As dynamic ecosystems that transition between flowing, pool, and dry states, IRES are

  9. The nucleosome assembly activity of NAP1 is enhanced by Alien.

    Science.gov (United States)

    Eckey, Maren; Hong, Wei; Papaioannou, Maria; Baniahmad, Aria

    2007-05-01

    The assembly of nucleosomes into chromatin is essential for the compaction of DNA and inactivation of the DNA template to modulate and repress gene expression. The nucleosome assembly protein 1, NAP1, assembles nucleosomes independent of DNA synthesis and was shown to enhance coactivator-mediated gene expression, suggesting a role for NAP1 in transcriptional regulation. Here, we show that Alien, known to harbor characteristics of a corepressor of nuclear hormone receptors such as of the vitamin D receptor (VDR), binds in vivo and in vitro to NAP1 and modulates its activity by enhancing NAP1-mediated nucleosome assembly on DNA. Furthermore, Alien reduces the accessibility of the histones H3 and H4 for NAP1-promoted assembly reaction. This indicates that Alien sustains and reinforces the formation of nucleosomes. Employing deletion mutants of Alien suggests that different regions of Alien are involved in enhancement of NAP1-mediated nucleosome assembly and in inhibiting the accessibility of the histones H3 and H4. In addition, we provide evidence that Alien is associated with chromatin and with micrococcus nuclease-prepared nucleosome fractions and interacts with the histones H3 and H4. Furthermore, chromatin immunoprecipitation and reimmunoprecipitation experiments suggest that NAP1 and Alien localize to the endogenous CYP24 promoter in vivo, a VDR target gene. Based on these findings, we present here a novel pathway linking corepressor function with nucleosome assembly activity.

  10. Enhanced multimaterial 4D printing with active hinges

    Science.gov (United States)

    Akbari, Saeed; Hosein Sakhaei, Amir; Kowsari, Kavin; Yang, Bill; Serjouei, Ahmad; Yuanfang, Zhang; Ge, Qi

    2018-06-01

    Despite great progress in four-dimensional (4D) printing, i.e. three-dimensional (3D) printing of active (stimuli-responsive) materials, the relatively low actuation force of the 4D printed structures often impedes their engineering applications. In this study, we use multimaterial inkjet 3D printing technology to fabricate shape memory structures, including a morphing wing flap and a deployable structure, which consist of active and flexible hinges joining rigid (non-active) parts. The active hinges, printed from a shape memory polymer (SMP), lock the structure into a second temporary shape during a thermomechanical programming process, while the flexible hinges, printed from an elastomer, effectively increase the actuation force and the load-bearing capacity of the printed structure as reflected in the recovery ratio. A broad range of mechanical properties such as modulus and failure strain can be achieved for both active and flexible hinges by varying the composition of the two base materials, i.e. the SMP and the elastomer, to accommodate large deformation induced during programming step, and enhance the recovery in the actuating step. To find the important design parameters, including local deformation, shape fixity and recovery ratio, we conduct high fidelity finite element simulations, which are able to accurately predict the nonlinear deformation of the printed structures. In addition, a coupled thermal-electrical finite element analysis was performed to model the heat transfer within the active hinges during the localized Joule heating process. The model predictions showed good agreement with the measured temperature data and were used to find the major parameters affecting temperature distribution including the applied voltage and the convection rate.

  11. Case study on total electron content enhancements at low latitudes during low geomagnetic activities before the storms

    Directory of Open Access Journals (Sweden)

    Libo Liu

    2008-05-01

    Full Text Available Sometimes the ionospheric total electron content (TEC is significantly enhanced during low geomagnetic activities before storms. In this article, we investigate the characteristics of those interesting TEC enhancements using regional and global TEC data. We analyzed the low-latitude TEC enhancement events that occurred around longitude 120° E on 10 February 2004, 21 January 2004, and 4 March 2001, respectively. The TEC data are derived from regional Global Positioning System (GPS observations in the Asia/Australia sector as well as global ionospheric maps (GIMs produced by Jet Propulsion Laboratory (JPL. Strong enhancements under low geomagnetic activity before the storms are simultaneously presented at low latitudes in the Asia/Australia sector in regional TEC and JPL GIMs. These TEC enhancements are shown to be regional events with longitudinal and latitudinal extent. The regions of TEC enhancements during these events are confined at narrow longitude ranges around longitude 120° E. The latitudinal belts of maxima of enhancements locate around the northern and southern equatorial ionization anomaly (EIA crests, which are consistent with those low-latitude events presented by Liu et al. (2008. During the 4 March 2001 event, the total plasma density Ni observed by the Defense Meteorological Satellite Program (DMSP spacecraft F13 at 840 km altitude are of considerably higher values on 4 March than on the previous day in the TEC enhanced regions. Some TEC enhancement events are possibly due to contributions from auroral/magnetospheric origins; while there are also quasi-periodic enhancement events not related to geomagnetic activity and associated probably with planetary wave type oscillations (e.g. the 6 January 1998 event. Further investigation is warrented to identify/separate contributions from possible sources.

  12. Enhanced neutrophil chemotactic activity after bronchial challenge in subjects with grain dust-induced asthma.

    Science.gov (United States)

    Park, H S; Jung, K S

    1998-03-01

    There have been few reports suggesting involvement of neutrophils in induction of bronchoconstriction after inhalation of grain dust. To understand the role of neutrophils in pathogenesis of grain dust-induced asthma. We observed serum neutrophil chemotactic activity during grain dust-bronchoprovocation tests in six asthmatic subjects with positive bronchial challenges (group I). They were compared with those of six symptomatic subjects from the same workplace with negative bronchial challenges (group II). After grain dust inhalation, serum neutrophil chemotactic activity significantly increased at 30 minutes (P = .028), and then decreased to baseline level at 240 minutes (P = .028) in five subjects of group I having isolated early asthmatic responses. Enhanced neutrophil chemotactic activity was persistent for up to 240 minutes in one asthmatic subject having both early and late asthmatic responses. There was, however, no significant change in serum neutrophil chemotactic activity during bronchial challenges in subjects of group II. Pre-incubation of sera with anti-interleukin-8 (IL-8) antibody did not affect the neutrophil chemotactic activity results of group I subjects. These results suggest that enhanced neutrophil chemotactic activity distinct from IL-8 may contribute to significant bronchoconstriction induced by grain dust.

  13. Black ginseng activates Akt signaling, thereby enhancing myoblast differentiation and myotube growth

    Directory of Open Access Journals (Sweden)

    Soo-Yeon Lee

    2018-01-01

    Conclusion: BG enhances myoblast differentiation and myotube hypertrophy by activating Akt/mTOR/p70S6k axis. Thus, our study demonstrates that BG has promising potential to treat or prevent muscle loss related to aging or other pathological conditions, such as diabetes.

  14. Enhancement of knowledge construction activities utilizing 21st century learning design rubric

    Science.gov (United States)

    Pedoche, Margarette Anne U.; Taladua, Janica Mae M.; Panal, Geicky Pearl C.; Magsayo, Joy R.; Guarin, Rica Mae B.; Myrna, H. Lahoylahoy

    2018-01-01

    The main objective of the study was to enhance knowledge construction activities on its design particularly the objectives, support materials, student activities and assessment tools. Activities from the 2nd Quarter of Science Learners Material were the basis in the adaptation of activities. The adapted activities were evaluated by the In-service Science teachers and undergone modification by the researchers based on the teacher's comments and suggestions. It was then evaluated, revised, and validated, tried-out using the 21st CLD Rubric. Subjects of the study were 110 students from Grade 7-B, Grade 7-D, Grade 7-F in Geronima Cabrera National High School, Kolambugan, Lanao del Norte during the academic year 2016-2017, the study to determine their learning capabilities investigated by the use of Knowledge Construction Activities in the 21st Century Classroom, to investigate how the lessons were understood and appreciated by students, to stimulate interpretation, analysis, synthesizing, or evaluating ideas and develop critical thinking. Both quantitative and qualitative data were obtained from the students' scores in three activities. Results showed that there was a significant difference between the pretest and posttest scores of students. Mean scores between the pretest and posttest showed a mean difference of 3.35, thus the null hypothesis was rejected. It could be concluded with sufficient evidence to show that the students had basically low prior knowledge about the topic ecosystem. A significant difference was seen in the pretest and posttest, scores of the activities and Ecosystem model results after the implementation phase that a knowledge construction type of activity was better than the traditional one for it promoted meaningful learning and active engagement of students. Based on the results, it was clear that the use of knowledge construction activities had an effect on student's achievement in comparison to traditional teaching method. Thus, it was

  15. Cellular cooperation in lymphocyte activation. III. B-cell helper effect in the enhancement of T-cell response.

    Science.gov (United States)

    Kasahara, T; Kin, K; Itoh, Y; Kawai, T; Kano, Y; Shioiri-Nakano, K

    1979-01-01

    T and B cells were purified from human tonsil and peripheral blood by the removal of phagocytic cells, followed by filtration through a nylon fiber column (NC) and E-rosette formation. Purified T and B cells contained less than 1% of other cell types. The responses of T cells to concanavalin A (Con A) and soluble protein A were greatly enhanced in the presence of autologous B cells. Participation of B cells in T-cell enhancement was confirmed by the following observations: (a) purified B copulation, which was separated further from adherent B cells, retained its enhancing activity. (b) Another adherent cell-free B-cell preparation, which was purified from the NC-passed fraction, and (c) no T lymphoid but some B lymphoid cell lines, elicited strong T-cell enhancement. It was also found that the enhancing capacity of B cells required no metabolic activity, but rather an intact cell form and direct cell-to-cell contact with responding cells. The stimulatory determinants on B cells were resistant to trypsin and neuraminidase treatment. In this paper a hypothesis will be presented that at least two signals are prerequisite for the effective activation of T cells.

  16. PTP1B Inhibition Causes Rac1 Activation by Enhancing Receptor Tyrosine Kinase Signaling

    Directory of Open Access Journals (Sweden)

    Ayako Tsuchiya

    2014-04-01

    Full Text Available Background/Aims: The present study investigated the signaling pathway underlying Rac1 activation induced by the linoleic acid derivative 8-[2-(2-pentyl-cyclopropylmethyl-cyclopropyl]-octanoic acid (DCP-LA. Methods: Activity of protein tyrosine phosphatase 1B (PTP1B was assayed under cell-free conditions. Western blot was carried out to quantify phosphorylation of insulin receptor substrate-1 (IRS-1 and Akt in PC-12 cells. Rac1 activity was monitored in the föerster resonance energy transfer (FRET analysis using living and fixed PC-12 cells. Results: DCP-LA markedly suppressed PTP1B activity in a concentration (100 pM-100 µM-dependent manner. In the DCP-LA binding assay, fluorescein-conjugated DCP-LA produced a single fluorescent signal band at 60 kDa, corresponding to the molecule of PTP1B, and the signal was attenuated or abolished by co-treatment or pretreatment with non-conjugated DCP-LA. DCP-LA significantly enhanced nerve growth factor (NGF-stimulated phosphorylation of IRS-1 at Tyr1222 and Akt1/2 at Thr308/309 and Ser473/474 in PC-12 cells. In the FRET analysis, DCP-LA significantly enhanced NGF-stimulated Rac1 activation, which is abrogated by the phosphatidylinositol 3 kinase (PI3K inhibitor wortmannin, the 3-phosphoinositide-dependent protein kinase-1 (PDK1 inhibitor BX912, or the Akt inhibitor MK2206. Conclusion: The results of the present study show that DCP-LA-induced PTP1B inhibition, possibly through its direct binding, causes Rac1 activation by enhancing a pathway along a receptor tyrosine kinase (RTK/IRS-1/PI3K/Akt/Rac1 axis.

  17. Ultrasonic synthesis of fern-like ZnO nanoleaves and their enhanced photocatalytic activity

    International Nuclear Information System (INIS)

    Ma, Qing Lan; Xiong, Rui; Zhai, Bao-gai; Huang, Yuan Ming

    2015-01-01

    Graphical abstract: - Highlights: • Fern-like ZnO nanoleaves were synthesized by ultrasonicating Zn microcrystals in water. • A fern-like ZnO nanoleaf is a self-assembly of ZnO nanoplates along one ZnO nanorod. • Fern-like ZnO nanoleaves exhibit enhanced photocatalytic activity than ZnO nanocrystals. • The branched hierarchical structures are responsible for the enhanced photocatalytic activity. - Abstract: Two-dimensional fern-like ZnO nanoleaves were synthesized by ultrasonicating zinc microcrystals in water. The morphology, crystal structure, optical property and photocatalytic activity of the fern-like ZnO nanoleaves were characterized with scanning electron microscopy, X-ray diffraction, transmission electron microscopy, photoluminescence spectroscopy and ultraviolet–visible spectroscopy, respectively. It is found that one fern-like ZnO nanoleaf is composed of one ZnO nanorod as the central trunk and a number of ZnO nanoplates as the side branches in opposite pairs along the central ZnO nanorod. The central ZnO nanorod in the fern-like nanoleaves is about 1 μm long while the side-branching ZnO nanoplates are about 100 nm long and 20 nm wide. Further analysis has revealed that ZnO nanocrystals are the building blocks of the central ZnO nanorod and the side-branching ZnO nanoplates. Under identical conditions, fern-like ZnO nanoleaves exhibit higher photocatalytic activity in photodegrading methyl orange in aqueous solution than spherical ZnO nanocrystals. The first-order photocatalytic rate constant of the fern-like ZnO nanoleaves is about four times as large as that of the ZnO nanoparticles. The branched architecture of the hierarchical nanoleaves is suggested be responsible for the enhanced photocatalytic activity of the fern-like ZnO nanoleaves

  18. Self-efficacy enhancing intervention increases light physical activity in people with chronic obstructive pulmonary disease.

    Science.gov (United States)

    Larson, Janet L; Covey, Margaret K; Kapella, Mary C; Alex, Charles G; McAuley, Edward

    2014-01-01

    People with chronic obstructive pulmonary disease lead sedentary lives and could benefit from increasing their physical activity. The purpose of this study was to determine if an exercise-specific self-efficacy enhancing intervention could increase physical activity and functional performance when delivered in the context of 4 months of upper body resistance training with a 12-month follow-up. IN THIS RANDOMIZED CONTROLLED TRIAL, SUBJECTS WERE ASSIGNED TO: exercise-specific self-efficacy enhancing intervention with upper body resistance training (SE-UBR), health education with upper body resistance training (ED-UBR), or health education with gentle chair exercises (ED-Chair). Physical activity was measured with an accelerometer and functional performance was measured with the Functional Performance Inventory. Forty-nine people with moderate to severe chronic obstructive pulmonary disease completed 4 months of training and provided valid accelerometry data, and 34 also provided accelerometry data at 12 months of follow-up. The self-efficacy enhancing intervention emphasized meeting physical activity guidelines and increasing moderate-to-vigorous physical activity. Differences were observed in light physical activity (LPA) after 4 months of training, time by group interaction effect (P=0.045). The SE-UBR group increased time spent in LPA by +20.68±29.30 minutes/day and the other groups decreased time spent in LPA by -22.43±47.88 minutes/day and -25.73±51.76 minutes/day. Changes in LPA were not sustained at 12-month follow-up. There were no significant changes in moderate-to-vigorous physical activity, sedentary time, or functional performance. Subjects spent most of their waking hours sedentary: 72%±9% for SE-UBR, 68%±10% for ED-UBR, and 74%±9% for ED-Chair. The self-efficacy enhancing intervention produced a modest short-term increase in LPA. Further work is needed to increase the magnitude and duration of effect, possibly by targeting LPA.

  19. Photon activation therapy with 127I-deoxyuridine: measurement of dose enhancement in cultured mammalian cells

    International Nuclear Information System (INIS)

    Fairchild, R.G.; Laster, B.H.; Commerford, S.L.; Furcinitti, P.S.; Sylvester, B.; Gabel, D.; Popenoe, E.; Foster, S.

    1985-01-01

    A technique for radiation enhancement of conventional photon radiotherapy is outlined which has been called photon activation therapy (PAT) (6). High linear energy transfer (LET) radiations in the form of Auger electron distributions are generated by photons of appropriate energies, through photon activation of stable iodine incorporated as an analog of thymidine (Tyd) in DNA. Of the several halogenated deoxyribonucleosides evaluated, iodinated deoxyuridine (IdUrd) has been chosen as the only Tyd analog providing effective photon activation. This mechanism is combined with radiation sensitization produced by IdUrd to produce an overall radiation enhancement. Calculations show that at 5% replacement (IdUrd for Tyd) therapeutic (TG) will vary from ∼2 (single acute dose) to ∼17 (low dose rates associated with permanent implant brachytherapy). Parameters used in the calculation of TG have been evaluated in cell culture; dose enhancements obtained with x-rays (including photon activation) were found to be significantly higher than values measured with γ-rays (no photon activation). Comparison is made between theoretical and measured values. Because of the evident lack of repair of damage produced by both sensitization and photon activation, significant gains are expected to be realized following protracted irradiations. Exchanges (IdUrd for Tyd) for 105 have been obtained in vivo (murine tumors). The authors believe that the application of PAT would be most advantageous in the treatment of brain tumors (grade IV astrocytomas) with implanted 145 Sm sources

  20. A temporal gate for viral enhancers to co-opt Toll-like-receptor transcriptional activation pathways upon acute infection.

    Directory of Open Access Journals (Sweden)

    Kai A Kropp

    2015-04-01

    Full Text Available Viral engagement with macrophages activates Toll-Like-Receptors (TLRs and viruses must contend with the ensuing inflammatory responses to successfully complete their replication cycle. To date, known counter-strategies involve the use of viral-encoded proteins that often employ mimicry mechanisms to block or redirect the host response to benefit the virus. Whether viral regulatory DNA sequences provide an opportunistic strategy by which viral enhancer elements functionally mimic innate immune enhancers is unknown. Here we find that host innate immune genes and the prototypical viral enhancer of cytomegalovirus (CMV have comparable expression kinetics, and positively respond to common TLR agonists. In macrophages but not fibroblasts we show that activation of NFκB at immediate-early times of infection is independent of virion-associated protein, M45. We find upon virus infection or transfection of viral genomic DNA the TLR-agonist treatment results in significant enhancement of the virus transcription-replication cycle. In macrophage time-course infection experiments we demonstrate that TLR-agonist stimulation of the viral enhancer and replication cycle is strictly delimited by a temporal gate with a determined half-maximal time for enhancer-activation of 6 h; after which TLR-activation blocks the viral transcription-replication cycle. By performing a systematic siRNA screen of 149 innate immune regulatory factors we identify not only anticipated anti-viral and pro-viral contributions but also new factors involved in the CMV transcription-replication cycle. We identify a central convergent NFκB-SP1-RXR-IRF axis downstream of TLR-signalling. Activation of the RXR component potentiated direct and indirect TLR-induced activation of CMV transcription-replication cycle; whereas chromatin binding experiments using wild-type and enhancer-deletion virus revealed IRF3 and 5 as new pro-viral host transcription factor interactions with the CMV enhancer in

  1. Photometric Characterization of the Reductive Amination Scope of the Imine Reductases from Streptomyces tsukubaensis and Streptomyces ipomoeae.

    Science.gov (United States)

    Matzel, Philipp; Krautschick, Lukas; Höhne, Matthias

    2017-10-18

    Imine reductases (IREDs) have emerged as promising enzymes for the asymmetric synthesis of secondary and tertiary amines starting from carbonyl substrates. Screening the substrate specificity of the reductive amination reaction is usually performed by time-consuming GC analytics. We found two highly active IREDs in our enzyme collection, IR-20 from Streptomyces tsukubaensis and IR-Sip from Streptomyces ipomoeae, that allowed a comprehensive substrate screening with a photometric NADPH assay. We screened 39 carbonyl substrates combined with 17 amines as nucleophiles. Activity data from 663 combinations provided a clear picture about substrate specificity and capabilities in the reductive amination of these enzymes. Besides aliphatic aldehydes, the IREDs accepted various cyclic (C 4 -C 8 ) and acyclic ketones, preferentially with methylamine. IR-Sip also accepted a range of primary and secondary amines as nucleophiles. In biocatalytic reactions, IR-Sip converted (R)-3-methylcyclohexanone with dimethylamine or pyrrolidine with high diastereoselectivity (>94-96 % de). The nucleophile acceptor spectrum depended on the carbonyl substrate employed. The conversion of well-accepted substrates could also be detected if crude lysates were employed as the enzyme source. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Flow intermittence and ecosystem services in rivers of the Anthropocene

    Science.gov (United States)

    Intermittent rivers and ephemeral streams (IRES) are watercourses that cease flow at some point in time and space. Arguably Earth's most widespread type of flowing water, IRES are expanding where Anthropocenic climates grow drier and human demands for water escalate. However, IRE...

  3. Modulation of Translation Initiation Efficiency in Classical Swine Fever Virus

    DEFF Research Database (Denmark)

    Friis, Martin Barfred; Rasmussen, Thomas Bruun; Belsham, Graham J.

    Modulation of translation initiation efficiency on classical swine fever virus (CSFV) RNA can be achieved by targeted mutations within the internal ribosome entry site (IRES). In this study, the nucleotides 47 to 427, including the IRES region of the wt CSFV strain Paderborn, were amplified...... and inserted, under T7 promoter control, into mono- and dicistronic plasmids containing the reporter genes rLuc and fLuc. Mutant fragments of the IRES sequence were generated by overlap PCR and inserted into the reporter plasmids. To evaluate IRES functionality, translation of the rLUC was placed under...... viruses were obtained after one cell culture passage from constructs with more than 75 % translation efficiency compared to the wildtype IRES. cDNA was generated from these clones and sequenced to verify the maintenance of the changes in the IRES. These results show that full-length viable mutant viruses...

  4. Self-Assembled Complexes of Horseradish Peroxidase with Magnetic Nanoparticles Showing Enhanced Peroxidase Activity

    KAUST Repository

    Corgié , Sté phane C.; Kahawong, Patarawan; Duan, Xiaonan; Bowser, Daniel; Edward, Joseph B.; Walker, Larry P.; Giannelis, Emmanuel P.

    2012-01-01

    Bio-nanocatalysts (BNCs) consisting of horseradish peroxidase (HRP) self-assembled with magnetic nanoparticles (MNPs) enhance enzymatic activity due to the faster turnover and lower inhibition of the enzyme. The size and magnetization of the MNPs

  5. STRUCTURILE DE DEFLECTORI, FACTORI DE ÎMBUNĂTĂŢIRE AI HABITATULUI PISCICOL- STUDIU DE CAZ, RÂUL NICOLET (QUEBEC-CANADA

    Directory of Open Access Journals (Sweden)

    Marius DULGHERU

    2010-06-01

    Full Text Available Deflection structures factors for improve the fish habitat. Case study nicolet river (Quebec-Canada. Există câţiva factori care joacă un rol important în definirea calităţii habitatului fizic al râurilor, speciile de peşti manifestând preferinţe pentru anumite elemente hidraulice (viteză, adâncime, tipul sedimentelor etc. Un habitat sănătos este în mod normal caracterizat printr-o succesiune morfologică de vaduri şi adâncuri cu impact în oxigenarea apei, reproducerea şi hrănirea peştilor etc. Datorită importanţei recreaţionale a pescuitului, în Canada există un număr foarte mare de proiecte de îmbunătăţire a habitatului piscicol. In acest sens, deflectorii amplasaţi în albiile cursurilor de apă s-au dovedit a fi metoda cea mai de succes pentru habitatul păstrăvilor. Pe râul Nicolet (Quebec-Canada a fost monitorizată influenţa unor astfel de structuri inginereşti asupra menţinerii în timp a structurii de adânc. Din analiza evoluţiei morfologice şi morfometrice a adâncurilor (prin folosirea diferitelor ridicări topografice succesive din perioada 2000-2007, rezultă faptul că structurile inginereşti au un rol benefic în menţinerea unui habitat propice pentru peşti.

  6. Light-Enhanced Antibacterial Activity of Graphene Oxide, Mainly via Accelerated Electron Transfer.

    Science.gov (United States)

    Chong, Yu; Ge, Cuicui; Fang, Ge; Wu, Renfei; Zhang, He; Chai, Zhifang; Chen, Chunying; Yin, Jun-Jie

    2017-09-05

    Before graphene derivatives can be exploited as next-generation antimicrobials, we must understand their behavior under environmental conditions. Here, we demonstrate how exposure to simulated sunlight significantly enhances the antibacterial activity of graphene oxide (GO) and reveal the underlying mechanism. Our measurements of reactive oxygen species (ROS) showed that only singlet oxygen ( 1 O 2 ) is generated by GO exposed to simulated sunlight, which contributes only slightly to the oxidation of antioxidant biomolecules. Unexpectedly, we find the main cause of oxidation is light-induced electron-hole pairs generated on the surface of GO. These light-induced electrons promote the reduction of GO, introducing additional carbon-centered free radicals that may also enhance the antibacterial activities of GO. We conclude that GO-mediated oxidative stress mainly is ROS-independent; simulated sunlight accelerates the transfer of electrons from antioxidant biomolecules to GO, thereby destroying bacterial antioxidant systems and causing the reduction of GO. Our insights will help support the development of graphene for antibacterial applications.

  7. Fraction From Lycium barbarum Polysaccharides Reduces Immunotoxicity and Enhances Antitumor Activity of Doxorubicin in Mice.

    Science.gov (United States)

    Deng, Xiangliang; Luo, Shuang; Luo, Xia; Hu, Minghua; Ma, Fangli; Wang, Yuanyuan; Zhou, Lian; Huang, Rongrong

    2018-01-01

    The aim of the present study was to investigate whether fraction from Lycium barbarum polysaccharide (LBP) could reduce immunotoxicity and enhance antitumor activity of doxorubicin (Dox) in mice. A water-soluble LBP fraction, designated LBP3, was isolated from edible Chinese herbal Lycium barbarum and used in this study. To investigate the effect of LBP3 on Dox-induced immunotoxicity, tumor-free mice were used and treated with either normal saline, Dox, or Dox plus LBP3. To investigate the effect of LBP3 on antitumor activity of Dox, H22 tumor-bearing mice were used and treated with either normal saline, Dox, LBP3, or Dox plus LBP3. The results showed that LBP3 did not protect against the body weight loss caused by Dox, but it promoted the recovery of body weight starting at day 5 after Dox treatment in tumor-free mice. LBP3 also improved peripheral blood lymphocyte counts, promoted cell cycle recovery in bone marrow cells, and restored the cytotoxicity of natural killer cells. Furthermore, in H22 tumor-bearing mice, LBP3 enhanced antitumor activity of Dox and improved peripheral blood lymphocyte counts and the cytotoxicity of splenocytes. In brief, our results demonstrated that LBP3 could reduce the immunotoxicity and enhance antitumor activity of Dox.

  8. Incorporation of tantalum ions enhances the electrocatalytic activity of hexagonal WO3 nanowires for hydrogen evolution reaction

    International Nuclear Information System (INIS)

    Xie, Xiang; Mu, Wanjun; Li, Xingliang; Wei, Hongyuan; Jian, Yuan; Yu, Qianhong; Zhang, Rui; Lv, Kai; Tang, Hui; Luo, Shunzhong

    2014-01-01

    WO 3 has been identified as a promising candidate electrocatalyst for hydrogen evolution reaction (HER), because it can form a tungsten bronze (HxWO 3 ) which is highly electron and proton conducting. In this paper, we report that the electrocatalytic activity of WO 3 for HER can be enhanced by incorporation of tantalum ions (Ta 5+ ) into the lattice of WO 3 . The most active performance is achieved with the molar ratio of Ta/W being 0.01, which is two times more active than that of undoped WO 3 at an overpotential of -0.52 V. It is shown that incorporation of proper Ta 5+ into WO 3 can induce moderate defects and oxygen vacancies, as well as intercalate a higher amount of protons, which enhance the electron transfer and short the protons diffusion paths. These changes correlated positively with the enhanced catalytic HER activity. This study demonstrates, for the first time, that metal ions-doped WO 3 nanowires are promising electrocatalysts for HER

  9. Enhanced activation of RVLM-projecting PVN neurons in rats with chronic heart failure.

    Science.gov (United States)

    Xu, Bo; Zheng, Hong; Patel, Kaushik P

    2012-04-15

    Previous studies have indicated that there is increased activation of the paraventricular nucleus (PVN) in rats with chronic heart failure (CHF); however, it is not clear if the preautonomic neurons within the PVN are specifically overactive. Also, it is not known if these neurons have altered responses to baroreceptor or osmotic challenges. Experiments were conducted in rats with CHF (6-8 wk after coronary artery ligation). Spontaneously active neurons were recorded in the PVN, of which 36% were antidromically activated from the rostral ventrolateral medulla (RVLM). The baseline discharge rate in RVLM-projecting PVN (PVN-RVLM) neurons from CHF rats was significantly greater than in sham-operated (sham) rats (6.0 ± 0.6 vs. 2.6 ± 0.3 spikes/s, P neurons by 80% in CHF rats compared with 37% in sham rats. Fifty-two percent of spontaneously active PVN-RVLM neurons responded to changes in the mean arterial pressure (MAP). The changes in discharge rate in PVN-RVLM neurons after a reduction in MAP (+52 ± 7% vs. +184 ± 61%) or an increase in MAP (-42 ± 8% vs. -71 ± 6%) were significantly attenuated in rats with CHF compared with sham rats. Most PVN-RVLM neurons (63%), including all barosensitive PVN-RVLM neurons, were excited by an internal carotid artery injection of hypertonic NaCl (2.1 osmol/l), whereas a smaller number (7%) were inhibited. The increase in discharge rate in PVN-RVLM neurons to hypertonic stimulation was significantly enhanced in rats with CHF compared with sham rats (134 ± 15% vs. 92 ± 13%). Taken together, these data suggest that PVN-RVLM neurons are more active under basal conditions and this overactivation is mediated by an enhanced glutamatergic tone in rats with CHF. Furthermore, this enhanced activation of PVN-RVLM neurons may contribute to the altered responses to baroreceptor and osmotic challenges observed during CHF.

  10. Noninvasive evaluation of active lower gastrointestinal bleeding: comparison between contrast-enhanced MDCT and 99mTc-labeled RBC scintigraphy.

    Science.gov (United States)

    Zink, Stephen I; Ohki, Stephen K; Stein, Barry; Zambuto, Domenic A; Rosenberg, Ronald J; Choi, Jenny J; Tubbs, Daniel S

    2008-10-01

    The purpose of our study was to compare contrast-enhanced MDCT and (99m)Tc-labeled RBC scanning for the evaluation of active lower gastrointestinal bleeding. Over 17 months, 55 patients (32 men, 23 women; age range, 21-92 years) were evaluated prospectively with contrast-enhanced MDCT using 100 mL of iopromide 300 mg I/mL. Technetium-99m-labeled RBC scans were obtained on 41 of 55 patients and select patients underwent angiography for attempted embolization. Each imaging technique was reviewed in a blinded fashion for sensitivity for detection of active bleeding as well as the active lower gastrointestinal bleeding location. Findings were positive on both examinations in eight patients and negative on both examinations in 20 patients. Findings were positive on contrast-enhanced MDCT and negative on (99m)Tc-labeled RBC in two patients; findings were negative on contrast-enhanced MDCT and positive on (99m)Tc-labeled RBC in 11 patients. Statistics showed significant disagreement, with simple agreement = 68.3%, kappa = 0.341, and p = 0.014. Sixteen of 60 (26.7%) contrast-enhanced MDCT scans were positive prospectively, with all accurately localizing the site of bleeding and identification of the underlying lesion in eight of 16 (50%). Nineteen of 41 (46.3%) (99m)Tc-labeled RBC scans were positive. Eighteen of 41 matched patients went on to angiography. In four of these 18 (22.2%) patients, the site of bleeding was confirmed by angiography, but in 14 of 18 (77.8%), the findings were negative. Contrast-enhanced MDCT and (99m)Tc-labeled RBC scanning show significant disagreement for evaluation of active lower gastrointestinal bleeding. Contrast-enhanced MDCT appears effective for detection and localization in cases of active lower gastrointestinal bleeding in which hemorrhage is active at the time of CT.

  11. Development of microalgae biomaterials with enhanced antioxidant activity using electron beam

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Younghwa; Park, Hyunjin; Choi, Soojeong; Lee, Jaehwa [Silla Univ., Busan (Korea, Republic of)

    2013-07-01

    By increasing the antioxidant products (e. g. antioxidant enzyme, carotenoid, phycobiliproteins, chlorophyll, lipid phenolic compounds, etc.) in microalgae, it could be useful for industry. In this study, mutants of fresh water microalgae Arthrospira platensis (A. platensis) by high energy electron beam were isolated and characterized. Those selected mutants showed higher growth rate than parental strain. The antioxidant enzyme activity (SOD and POD), flavonoid, phenolic compound and phycocyanin of mutants were increased about 2 times compared to wild type. Moreover, DPPH radical scavenging activity was increased about 20%. Microalgae species with improved growth rate and enhanced active compounds make the commercial process more feasible in industry. Using microalgae mutants with increased antioxidant products, it is useful to develop microalgae biomaterials for neutraceuticals.

  12. Development of microalgae biomaterials with enhanced antioxidant activity using electron beam

    International Nuclear Information System (INIS)

    Kim, Younghwa; Park, Hyunjin; Choi, Soojeong; Lee, Jaehwa

    2013-01-01

    By increasing the antioxidant products (e. g. antioxidant enzyme, carotenoid, phycobiliproteins, chlorophyll, lipid phenolic compounds, etc.) in microalgae, it could be useful for industry. In this study, mutants of fresh water microalgae Arthrospira platensis (A. platensis) by high energy electron beam were isolated and characterized. Those selected mutants showed higher growth rate than parental strain. The antioxidant enzyme activity (SOD and POD), flavonoid, phenolic compound and phycocyanin of mutants were increased about 2 times compared to wild type. Moreover, DPPH radical scavenging activity was increased about 20%. Microalgae species with improved growth rate and enhanced active compounds make the commercial process more feasible in industry. Using microalgae mutants with increased antioxidant products, it is useful to develop microalgae biomaterials for neutraceuticals

  13. Loss of Subcellular Lipid Transport Due to ARV1 Deficiency Disrupts Organelle Homeostasis and Activates the Unfolded Protein Response*

    Science.gov (United States)

    Shechtman, Caryn F.; Henneberry, Annette L.; Seimon, Tracie A.; Tinkelenberg, Arthur H.; Wilcox, Lisa J.; Lee, Eunjee; Fazlollahi, Mina; Munkacsi, Andrew B.; Bussemaker, Harmen J.; Tabas, Ira; Sturley, Stephen L.

    2011-01-01

    The ARV1-encoded protein mediates sterol transport from the endoplasmic reticulum (ER) to the plasma membrane. Yeast ARV1 mutants accumulate multiple lipids in the ER and are sensitive to pharmacological modulators of both sterol and sphingolipid metabolism. Using fluorescent and electron microscopy, we demonstrate sterol accumulation, subcellular membrane expansion, elevated lipid droplet formation, and vacuolar fragmentation in ARV1 mutants. Motif-based regression analysis of ARV1 deletion transcription profiles indicates activation of Hac1p, an integral component of the unfolded protein response (UPR). Accordingly, we show constitutive splicing of HAC1 transcripts, induction of a UPR reporter, and elevated expression of UPR targets in ARV1 mutants. IRE1, encoding the unfolded protein sensor in the ER lumen, exhibits a lethal genetic interaction with ARV1, indicating a viability requirement for the UPR in cells lacking ARV1. Surprisingly, ARV1 mutants expressing a variant of Ire1p defective in sensing unfolded proteins are viable. Moreover, these strains also exhibit constitutive HAC1 splicing that interacts with DTT-mediated perturbation of protein folding. These data suggest that a component of UPR induction in arv1Δ strains is distinct from protein misfolding. Decreased ARV1 expression in murine macrophages also results in UPR induction, particularly up-regulation of activating transcription factor-4, CHOP (C/EBP homologous protein), and apoptosis. Cholesterol loading or inhibition of cholesterol esterification further elevated CHOP expression in ARV1 knockdown cells. Thus, loss or down-regulation of ARV1 disturbs membrane and lipid homeostasis, resulting in a disruption of ER integrity, one consequence of which is induction of the UPR. PMID:21266578

  14. Decoupling Intensity Radiated by the Emitter in Distance Estimation from Camera to IR Emitter

    Directory of Open Access Journals (Sweden)

    Carlos Andrés Luna Vázquez

    2013-05-01

    Full Text Available Various models using radiometric approach have been proposed to solve the problem of estimating the distance between a camera and an infrared emitter diode (IRED. They depend directly on the radiant intensity of the emitter, set by the IRED bias current. As is known, this current presents a drift with temperature, which will be transferred to the distance estimation method. This paper proposes an alternative approach to remove temperature drift in the distance estimation method by eliminating the dependence on radiant intensity. The main aim was to use the relative accumulated energy together with other defined models, such as the zeroth-frequency component of the FFT of the IRED image and the standard deviation of pixel gray level intensities in the region of interest containing the IRED image. By using the abovementioned models, an expression free of IRED radiant intensity was obtained. Furthermore, the final model permitted simultaneous estimation of the distance between the IRED and the camera and the IRED orientation angle. The alternative presented in this paper gave a 3% maximum relative error over a range of distances up to 3 m.

  15. Enhancement of human natural cytotoxicity by Plasmodium falciparum antigen activated lymphocytes

    DEFF Research Database (Denmark)

    Theander, T G; Pedersen, B K; Bygbjerg, I C

    1987-01-01

    Mononuclear cells (MNC) isolated from malaria immune donors and from donors never exposed to malaria were stimulated in vitro with soluble purified Plasmodium falciparum antigens (SPag) or PPD. After 7 days of culture the proliferative response and the cytotoxic activity against the natural killer...... were preincubated with interleukin 2 (IL-2) for one hour before the start of the cytotoxic assay. SPag activation did not enhance the cytotoxic activity of MNC which did not respond to the antigen in the proliferation assay, and preincubation of these cells with IL-2 did not increase the activity. PPD...

  16. Building novel Ag/CeO{sub 2} heterostructure for enhancing photocatalytic activity

    Energy Technology Data Exchange (ETDEWEB)

    Leng, Qiang; Yang, Dezhi; Yang, Qi [Department of Applied Physics, Chongqing University, Chongqing 400044 (China); Hu, Chenguo, E-mail: hucg@cqu.edu.cn [Department of Applied Physics, Chongqing University, Chongqing 400044 (China); Kang, Yue; Wang, Mingjun [Department of Applied Physics, Chongqing University, Chongqing 400044 (China); Hashim, Muhammad [Department of Applied Physics, Chongqing University, Chongqing 400044 (China); Applied Physics Department, Federal Urdu University of Arts Science and Technology, Islamabad (Pakistan)

    2015-05-15

    Highlights: • Ag nanoparticle is designed to building Schottky heterojunction on CeO{sub 2} nanocube. • The photocatalytic activity of Ag/CeO{sub 2} heterostructure is much enhanced. • 95.33% of MB can be effectively degraded within half an hour. • Ag as acceptor of photoelectrons blocks the recombination of electron–hole pairs. - Abstract: Stable and recyclable photocatalysts with high efficiency to degrade organic contamination are important and widely demanded under the threat of the environment pollution. Ag/CeO{sub 2} heterostructure is designed as a photocatalyst to degrade organic dye under the simulated sunlight. The catalytic activity of CeO{sub 2} nanocubes (NCs) to degrade methylene blue (MB) is obviously enhanced when Ag nanoparticles (NPs) are deposited on the surface of them. The weight ratio of Ag and CeO{sub 2} in forming high efficiency catalyst, the amount of Ag/CeO{sub 2} catalyst used in degradation process, and the dye concentration and pH value of the initial MB solution are examined systematically. 95.33% of MB can be effectively degraded within half an hour when 50 mg of Ag/CeO{sub 2} catalyst in an optimal weight ratio of 1:3, is added to the 100 mL of MB solution (c{sub 0} = 1 × 10{sup −5} mol L{sup −1}, pH 6.2). The mechanism of the enhanced catalytic activity of Ag/CeO{sub 2} heterostructure is discussed. The photocatalytic degradation rate is found to obey pseudo-first-order kinetics equations according to Langmuir–Hinshelwood model. The intermediate products in different stages during the degradation of MB are analyzed.

  17. The potential role of waste biomass in the future urban electricity system

    OpenAIRE

    Jiang, Yu; Werf, van der, Edwin; Ierland, van, Ekko C.; Keesman, Karel J.

    2017-01-01

    The share of intermittent renewable electricity (IRE) in the future urban electricity system is expected to increase significantly. Sufficient back-up capacity is needed in the period when IRE output is low. Bioenergy is both dispatchable and carbon-neutral, and can hence be a promising option to back up IRE. The objective of this study is to explore the potential of urban waste biomass in backing up IRE in an urban electricity system. An urban electricity system model is developed to project...

  18. Enhanced oxidation of naphthalene using plasma activation of TiO2/diatomite catalyst.

    Science.gov (United States)

    Wu, Zuliang; Zhu, Zhoubin; Hao, Xiaodong; Zhou, Weili; Han, Jingyi; Tang, Xiujuan; Yao, Shuiliang; Zhang, Xuming

    2018-04-05

    Non-thermal plasma technology has great potential in reducing polycyclic aromatic hydrocarbons (PAHs) emission. But in plasma-alone process, various undesired by-products are produced, which causes secondary pollutions. Here, a dielectric barrier discharge (DBD) reactor has been developed for the oxidation of naphthalene over a TiO 2 /diatomite catalyst at low temperature. In comparison to plasma-alone process, the combination of plasma and TiO 2 /diatomite catalyst significantly enhanced naphthalene conversion (up to 40%) and CO x selectivity (up to 92%), and substantially reduced the formation of aerosol (up to 90%) and secondary volatile organic compounds (up to near 100%). The mechanistic study suggested that the presence of the TiO 2 /diatomite catalyst intensified the electron energy in the DBD. Meantime, the energized electrons generated in the discharge activated TiO 2 , while the presence of ozone enhanced the activity of the TiO 2 /diatomite catalyst. This plasma-catalyst interaction led to the synergetic effect resulting from the combination of plasma and TiO 2 /diatomite catalyst, consequently enhanced the oxidation of naphthalene. Importantly, we have demonstrated the effectiveness of plasma to activate the photocatalyst for the deep oxidation of PAH without external heating, which is potentially valuable in the development of cost-effective gas cleaning process for the removal of PAHs in vehicle applications during cold start conditions. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Increased p21ras activity in human fibroblasts transduced with survivin enhances cell proliferation

    International Nuclear Information System (INIS)

    Temme, Achim; Diestelkoetter-Bachert, Petra; Schmitz, Marc; Morgenroth, Agnieszka; Weigle, Bernd; Rieger, Michael A.; Kiessling, Andrea; Rieber, E. Peter

    2005-01-01

    Survivin is critically involved in mitosis and when overexpressed enhances the activity of the Aurora B kinase, a serine-threonine kinase belonging to the family of oncogenic Aurora/IpI1p-related kinases. Both proteins interact with Ras GTPase-activating protein suggesting an impact on the Ras pathway. This study aimed at defining the role of survivin in proliferation and potential transformation of cells. When survivin was overexpressed in normal human lung fibroblasts, the characteristic track lanes of fibroblasts were disturbed and the rate of cell proliferation was increased. An enhanced level of p21 ras mRNA and protein expression and concomitant rise in levels of activated p21 ras were observed. Despite increased proliferation cell survival remained dependent on serum and cells were not able to form colonies in soft agar assays. These data suggest that overexpression of survivin increases cell growth but, despite the increase in active p21 ras , is not sufficient to transform primary cells. Yet, in addition to its anti-apoptotic function it might contribute to the accelerated growth of tumour cells by increasing p21 ras activity

  20. Solvothermal synthesis of hierarchical TiO{sub 2} nanostructures with tunable morphology and enhanced photocatalytic activity

    Energy Technology Data Exchange (ETDEWEB)

    Fan, Zhenghua [School of Physics and Materials Science, Anhui University, Hefei 230601 (China); Meng, Fanming, E-mail: mrmeng@ahu.edu.cn [School of Physics and Materials Science, Anhui University, Hefei 230601 (China); Key laboratory of Materials Modification by Laser, Ion and Electron Beams (Dalian University of Technology), Ministry of Education, Dalian 116024 (China); Zhang, Miao [School of Physics and Materials Science, Anhui University, Hefei 230601 (China); Wu, Zhenyu [College of Chemistry & Chemical Engineering, Anhui University, Hefei 230601 (China); Sun, Zhaoqi; Li, Aixia [School of Physics and Materials Science, Anhui University, Hefei 230601 (China)

    2016-01-01

    Graphical abstract: - Highlights: • Hierarchical anatase TiO{sub 2} nanostructures with enhanced photocatalytic activity are synthesized by solvothermal method. • A mechanism for enhanced photocatalytic activity of chrysanthemum-like hierarchical TiO{sub 2} nanostructures is proposed. • A possible formation mechanism is suggested to explain the transformation from rose-like to chrysanthemum-like, and to sea-urchin-like. - Abstract: This paper presents controllable growth and photocatalytic activity of TiO{sub 2} hierarchical nanostructures by solvothermal method at different temperatures. It is revealed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) that the morphology of TiO{sub 2} can be effectively controlled as rose-like, chrysanthemum-like and sea-urchin-like only changing solvothermal temperature. BET surface area analysis confirms the presence of a mesoporous network in all the nanostructures, and shows high surface area at relatively high temperature. The photocatalytic activities of the photocatalysts are evaluated by the photodegradation of RhB under UV light irradiation. The TiO{sub 2} samples exhibit high activity on the photodegradation of RhB, which is higher than that of the commercial P25. The enhancement in photocatalytic performance can be attributed to the synergetic effect of the surface area, crystallinity, band gap and crystalline size.

  1. Investigation of repressive and enhancive effects of fruit extracts on the activity of glucose-6-phophatase.

    Science.gov (United States)

    Zahoor, Muhammad; Jan, Muhammad Rasul; Naz, Sumaira

    2016-11-01

    Glucose-6-phosphatase is a key enzyme of glucose metabolic pathways. Deficiency of this enzyme leads to glycogen storage disease. This enzyme also plays a negative role in diabetes mellitus disorder in which the catalytic activity of this enzyme increases. Thus there is need for activators to enhance the activity of glucose-6-phosphatase in glycogen storage disease of type 1b while in diabetes mellitus repressors are needed to reduce its activity. Crude extracts of apricot, fig, mulberry and apple fruits were investigated for their repressive/enhancive effects on glucose-6-phosphatase in vivo. Albino mice were used as experimental animal. All the selected extracts showed depressive effects on glucose-6-phosphatase, which shows that all these extracts can be used as antidiabetic supplement of food. The inhibitory pattern was competitive one, which was evident from the effect of increasing dose from 1g/Kg body weight to 3g/Kg body weight for all the selected fruit extracts. However fig and apple fruit extracts showed high repressive effects for high doses as compared to apricot and mulberry fruit extracts. None of these selected fruit extracts showed enhancive effect on glucose-6-phosphatase activity. All these fruits or their extracts can be used as antidiabetic dietary supplement for diabetes mellitus.

  2. The Effectiveness of Cooperative Learning Activities in Enhancing EFL Learners' Fluency

    Science.gov (United States)

    Alrayah, Hassan

    2018-01-01

    This research-paper aims at examining the effectiveness of cooperative learning activities in enhancing EFL learners' fluency. The researcher has used the descriptive approach, recorded interviews for testing fluency as tools of data collection and the software program SPSS as a tool for the statistical treatment of data. Research sample consists…

  3. Circadian variations of interferon-induced enhancement of human natural killer (NK) cell activity.

    Science.gov (United States)

    Gatti, G; Cavallo, R; Sartori, M L; Carignola, R; Masera, R; Delponte, D; Salvadori, A; Angeli, A

    1988-01-01

    We searched for circadian changes in the enhancement of the NK activity after exposure to IFN-gamma of peripheral blood mononuclear (PBM) cells obtained serially throughout the 24-h cycle. In August-October 1986, blood was drawn from 7 healthy, diurnally active and nocturnally resting male volunteers (22-34 yr) at 4-h intervals for 24 h starting at 08:00. PBM cells were immediately separated and assayed for NK cell activity, using K 562 cultured cells as a target in a 4-h 51Cr release assay after prior incubation for 20 h with buffer or 300 IU rIFN-gamma. Circadian variations of the spontaneous NK cell cytotoxicity were apparent; the activity was at its maximum at the end of the night or in the early morning and then declined in the afternoon. The 24-h rhythmic pattern was validated with statistical significance by the Cosinor method (p less than 0.02; acrophase 04:22). Maximum enhancement by IFN-gamma was attained in the second part of the night or in the early morning, i.e. in phase with the peak of the spontaneous NK cell activity. A significant circadian rhythm of the percent increase above control levels was validated by the Cosinor method (p less than 0.01; acrophase 04:03). Our findings may be of relevance to a better understanding of the mechanisms of control of human NK activity and warrant consideration as an approach to improve the effectiveness of time-qualified immunotherapy.

  4. Antimicrobial activity of Bacillus amyloliquefaciens LBM 5006 is enhanced in the presence of Escherichia coli.

    Science.gov (United States)

    Benitez, Lisianne; Correa, AnaPaula; Daroit, Daniel; Brandelli, Adriano

    2011-03-01

    Increased antimicrobial activity was observed when Bacillus amyloliquefaciens LBM 5006 strain was cultivated in the presence of thermally inactivated cells of Escherichia coli, but not with Staphylococcus aureus, Listeria monocytogenes, or Bacillus cereus. E. coli also enhanced the antimicrobial activity when it was added to the medium in the form of living cells or as cell debris after cellular fractionation. No inducing activity was observed with addition of cell-free supernatant of E. coli cultures, suggesting that inducing factor is associated to the cells. Polyacrylamide gel electrophoresis revealed that additional peptide bands are secreted when B. amyloliquefaciens was cultivated in the presence of cell debris of E. coli. These results suggest that the presence of intact or inactivated E. coli enhanced the synthesis of antimicrobial peptides by B. amyloliquefaciens LBM 5006.

  5. C/EBPα Activates Pre-existing and De Novo Macrophage Enhancers during Induced Pre-B Cell Transdifferentiation and Myelopoiesis

    Directory of Open Access Journals (Sweden)

    Chris van Oevelen

    2015-08-01

    Full Text Available Transcription-factor-induced somatic cell conversions are highly relevant for both basic and clinical research yet their mechanism is not fully understood and it is unclear whether they reflect normal differentiation processes. Here we show that during pre-B-cell-to-macrophage transdifferentiation, C/EBPα binds to two types of myeloid enhancers in B cells: pre-existing enhancers that are bound by PU.1, providing a platform for incoming C/EBPα; and de novo enhancers that are targeted by C/EBPα, acting as a pioneer factor for subsequent binding by PU.1. The order of factor binding dictates the upregulation kinetics of nearby genes. Pre-existing enhancers are broadly active throughout the hematopoietic lineage tree, including B cells. In contrast, de novo enhancers are silent in most cell types except in myeloid cells where they become activated by C/EBP factors. Our data suggest that C/EBPα recapitulates physiological developmental processes by short-circuiting two macrophage enhancer pathways in pre-B cells.

  6. Enhancement of lysyl-tRNA synthetase activity in the Enterobacteriaceae

    International Nuclear Information System (INIS)

    Hickey, E.W.; Hirshfield, I.

    1987-01-01

    Lysyl-tRNA synthetase (LRS) in E. coli is coded by two genes, one constitutive, and the other inducible; the latter is a cell stress protein. To determine if this system is wide spread in prokaryotes, the inducibility of LRS was first tested in eight members of the Enterobacteriaceae using cultural conditions known to induce the enzyme in E. coli K-12. Uninduced control cultures were grown to an O.D. of 0.2 at 580 nm in a supplemented minimal medium (SMM), pH 7.0 at 37 0 C. Induction stimuli include: growth in SMM with 3mM Gly-L-Leu; growth in SMM as above, but with the initial pH adjusted to 5.0; or growth in Difco AC Broth to early stationary phase with a concomitant drop in the pH of the medium below 5.5. LRS activity was assayed in whole-cell sonic extracts by the aminoacylation of crude E. coli tRNA by 14 C-lysine at pH 7.8 for three minutes. When E. aerogenes, K. pneumoniae, C. freundii, and S. typhimurium were grown in AC Broth, LRS activity was enhanced 2 to 4 fold. The enzyme is induced 2 to 4 fold in C. freundii and S. typhimurium upon growth at pH 5.0, whereas E. coli, K.; pneumoniae, and E. aerogenes show only a 1.5 fold induction. The peptide Gly-L-Leu enhanced LRS activity only in E. coli. LRS was not found to be inducible in S. marcescens, M. morganii, P. mirabilis, or P. vulgaris by any of the stimuli

  7. Enhanced photocatalytic activity of titania-silica mixed oxide prepared via basic hydrolyzation

    International Nuclear Information System (INIS)

    Xie Chao; Xu Zili; Yang Qiujing; Xue Baoyong; Du Yaoguo; Zhang Jiahua

    2004-01-01

    Two different synthesis routes were applied to prepare TiO 2 -XSiO 2 (X denotes mol% of silica in titania-silica mixed oxides) with different silica concentrations by using ammonia water as hydrolysis catalyst. Through comparing the photocatalytic performance of two sets of mixed oxides, we found that the photocatalytic activity of mixed oxides prepared via the route which can promote homogeneity, was significantly enhanced as compared with that of counterparts prepared via the another route, and the highest photocatalytic activity obtained by adding about 9.1 mol% silica into titania was much higher than that of pure TiO 2 . The mixed oxides were investigated by means of XRD, thermal analysis, UV-vis, FT-IR and XPS. The characterization results suggest that, in comparison with pure TiO 2 , the mixed oxides exhibit smaller crystallite size and higher thermal stability which can elevate the temperature of anatase to rutile phase transformation due to the addition of silica. Furthermore, Broensted acidity, which is associated with the formation of Ti-O-Si hetero linkages where tetrahedrally coordinated silica is chemically mixed with the octahedral titania matrix, may be a very important contribution to the enhanced photocatalytic activity of titania-silica mixed oxides as well

  8. Enhanced oxygen reduction activity on surface-decorated perovskite thin films for solid oxide fuel cells

    KAUST Repository

    Mutoro, Eva; Crumlin, Ethan J.; Biegalski, Michael D.; Christen, Hans M.; Shao-Horn, Yang

    2011-01-01

    Surface-decoration of perovskites can strongly affect the oxygen reduction activity, and therefore is a new and promising approach to improve SOFC cathode materials. In this study, we demonstrate that a small amount of secondary phase on a (001) La 0.8Sr 0.2CoO 3-δ (LSC) surface can either significantly activate or passivate the electrode. LSC (001) microelectrodes prepared by pulsed laser deposition on a (001)-oriented yttria-stabilized zirconia (YSZ) substrate were decorated with La-, Co-, and Sr-(hydr)oxides/carbonates. "Sr"-decoration with nanoparticle coverage in the range from 50% to 80% of the LSC surface enhanced the surface exchange coefficient, k q, by an order of magnitude while "La"- decoration and "Co"-decoration led to no change and reduction in k q, respectively. Although the physical origin for the enhancement is not fully understood, results from atomic force microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy suggest that the observed k q enhancement for "Sr"-decorated surfaces can be attributed largely to catalytically active interface regions between surface Sr-enriched particles and the LSC surface. © 2011 The Royal Society of Chemistry.

  9. The vitamin-like dietary supplement para-aminobenzoic acid enhances the antitumor activity of ionizing radiation

    International Nuclear Information System (INIS)

    Xavier, Sandhya; MacDonald, Shannon; Roth, Jennifer; Caunt, Maresa; Akalu, Abebe; Morais, Danielle; Buckley, Michael T.; Liebes, Leonard; Formenti, Silvia C.; Brooks, Peter C.

    2006-01-01

    Purpose: To determine whether para-aminobenzoic acid (PABA) alters the sensitivity of tumor cells to ionizing radiation in vitro and in vivo. Methods and Materials: Cellular proliferation was assessed by WST-1 assays. The effects of PABA and radiation on tumor growth were examined with chick embryo and murine models. Real-time reverse transcriptase-polymerase chain reaction and Western blotting were used to quantify p21 CIP1 and CDC25A levels. Results: Para-aminobenzoic acid enhanced (by 50%) the growth inhibitory activity of radiation on B16F10 cells, whereas it had no effect on melanocytes. Para-aminobenzoic acid enhanced (50-80%) the antitumor activity of radiation on B16F10 and 4T1 tumors in vivo. The combination of PABA and radiation therapy increased tumor apoptosis. Treatment of tumor cells with PABA increased expression of CDC25A and decreased levels of p21 CIP1 . Conclusions: Our findings suggest that PABA might represent a compound capable of enhancing the antitumor activity of ionizing radiation by a mechanism involving altered expression of proteins known to regulate cell cycle arrest

  10. Microbial Consortium with High Cellulolytic Activity (MCHCA for enhanced biogas production.

    Directory of Open Access Journals (Sweden)

    Krzysztof ePoszytek

    2016-03-01

    Full Text Available The use of lignocellulosic biomass as a substrate in agricultural biogas plants is very popular and yields good results. However, the efficiency of anaerobic digestion, and thus biogas production, is not always satisfactory due to the slow or incomplete degradation (hydrolysis of plant matter. To enhance the solubilization of the lignocellulosic biomass various physical, chemical and biological pretreatment methods are used.The aim of this study was to select and characterize cellulose-degrading bacteria, and to construct a microbial consortium, dedicated for degradation of maize silage and enhancing biogas production from this substrate.Over one hundred strains of cellulose-degrading bacteria were isolated from: sewage sludge, hydrolyzer from an agricultural biogas plant, cattle slurry and manure. After physiological characterization of the isolates, sixteen strains (representatives of Bacillus, Providencia and Ochrobactrum genera were chosen for the construction of a Microbial Consortium with High Cellulolytic Activity, called MCHCA. The selected strains had a high endoglucanase activity (exceeding 0.21 IU/mL CMCase activity and a wide range of tolerance to various physical and chemical conditions. Lab-scale simulation of biogas production using the selected strains for degradation of maize silage was carried out in a two-bioreactor system, similar to those used in agricultural biogas plants.The obtained results showed that the constructed MCHCA consortium is capable of efficient hydrolysis of maize silage, and increases biogas production by even 38%, depending on the inoculum used for methane fermentation. The results in this work indicate that the mesophilic Microbial Consortium with High Cellulolytic Activity has a great potential for application on industrial scale in agricultural biogas plants.

  11. Strategies to enhance biologically active-secondary metabolites in cell cultures of Artemisia - current trends.

    Science.gov (United States)

    Ali, Mohammad; Abbasi, Bilal Haider; Ahmad, Nisar; Khan, Haji; Ali, Gul Shad

    2017-11-01

    The genus Artemisia has been utilized worldwide due to its immense potential for protection against various diseases, especially malaria. Artemisia absinthium, previously renowned for its utilization in the popular beverage absinthe, is gaining resurgence due to its extensive pharmacological activities. Like A. annua, this species exhibits strong biological activities like antimalarial, anticancer and antioxidant. Although artemisinin was found to be the major metabolite for its antimalarial effects, several flavonoids and terpenoids are considered to possess biological activities when used alone and also to synergistically boost the bioavailability of artemisinin. However, due to the limited quantities of these metabolites in wild plants, in vitro cultures were established and strategies have been adopted to enhance medicinally important secondary metabolites in these cultures. This review elaborates on the traditional medicinal uses of Artemisia species and explains current trends to establish cell cultures of A. annua and A. absinthium for enhanced production of medicinally important secondary metabolites.

  12. Albumin Enhances Caspofungin Activity against Aspergillus Species by Facilitating Drug Delivery to Germinating Hyphae.

    Science.gov (United States)

    Ioannou, Petros; Andrianaki, Aggeliki; Akoumianaki, Tonia; Kyrmizi, Irene; Albert, Nathaniel; Perlin, David; Samonis, George; Kontoyiannis, Dimitrios P; Chamilos, Georgios

    2015-12-07

    The modest in vitro activity of echinocandins against Aspergillus implies that host-related factors augment the action of these antifungal agents in vivo. We found that, in contrast to the other antifungal agents (voriconazole, amphotericin B) tested, caspofungin exhibited a profound increase in activity against various Aspergillus species under conditions of cell culture growth, as evidenced by a ≥4-fold decrease in minimum effective concentrations (MECs) (P = 0. 0005). Importantly, the enhanced activity of caspofungin against Aspergillus spp. under cell culture conditions was strictly dependent on serum albumin and was not observed with the other two echinocandins, micafungin and anidulafungin. Of interest, fluorescently labeled albumin bound preferentially on the surface of germinating Aspergillus hyphae, and this interaction was further enhanced upon treatment with caspofungin. In addition, supplementation of cell culture medium with albumin resulted in a significant, 5-fold increase in association of fluorescently labeled caspofungin with Aspergillus hyphae (P hyphae. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  13. Albumin Enhances Caspofungin Activity against Aspergillus Species by Facilitating Drug Delivery to Germinating Hyphae

    Science.gov (United States)

    Ioannou, Petros; Andrianaki, Aggeliki; Akoumianaki, Tonia; Kyrmizi, Irene; Albert, Nathaniel; Perlin, David; Samonis, George

    2015-01-01

    The modest in vitro activity of echinocandins against Aspergillus implies that host-related factors augment the action of these antifungal agents in vivo. We found that, in contrast to the other antifungal agents (voriconazole, amphotericin B) tested, caspofungin exhibited a profound increase in activity against various Aspergillus species under conditions of cell culture growth, as evidenced by a ≥4-fold decrease in minimum effective concentrations (MECs) (P = 0. 0005). Importantly, the enhanced activity of caspofungin against Aspergillus spp. under cell culture conditions was strictly dependent on serum albumin and was not observed with the other two echinocandins, micafungin and anidulafungin. Of interest, fluorescently labeled albumin bound preferentially on the surface of germinating Aspergillus hyphae, and this interaction was further enhanced upon treatment with caspofungin. In addition, supplementation of cell culture medium with albumin resulted in a significant, 5-fold increase in association of fluorescently labeled caspofungin with Aspergillus hyphae (P Aspergillus hyphae. PMID:26643329

  14. Activity Enhancement Based on the Chemical Equilibrium of Multiple-Subunit Nitrile Hydratase from Bordetella petrii.

    Science.gov (United States)

    Liu, Yi; Liu, Ping; Lin, Lu; Zhao, Yueqin; Zhong, Wenjuan; Wu, Lunjie; Zhou, Zhemin; Sun, Weifeng

    2016-09-01

    The maturation mechanism of nitrile hydratase (NHase) of Pseudomonas putida NRRL-18668 was discovered and named as "self-subunit swapping." Since the NHase of Bordetella petrii DSM 12804 is similar to that of P. putida, the NHase maturation of B. petrii is proposed to be the same as that of P. putida. However, there is no further information on the application of NHase according to these findings. We successfully rapidly purified NHase and its activator through affinity his tag, and found that the cell extracts of NHase possessed multiple types of protein ingredients including α, β, α2β2, and α(P14K)2 who were in a state of chemical equilibrium. Furthermore, the activity was significantly enhanced through adding extra α(P14K)2 to the cell extracts of NHase according to the chemical equilibrium. Our findings are useful for the activity enhancement of multiple-subunit enzyme and for the first time significantly increased the NHase activity according to the chemical equilibrium.

  15. Kaempferol enhances endothelium-dependent relaxation in the porcine coronary artery through activation of large-conductance Ca(2+) -activated K(+) channels.

    Science.gov (United States)

    Xu, Y C; Leung, S W S; Leung, G P H; Man, R Y K

    2015-06-01

    Kaempferol, a plant flavonoid present in normal human diet, can modulate vasomotor tone. The present study aimed to elucidate the signalling pathway through which this flavonoid enhanced relaxation of vascular smooth muscle. The effect of kaempferol on the relaxation of porcine coronary arteries to endothelium-dependent (bradykinin) and -independent (sodium nitroprusside) relaxing agents was studied in an in vitro organ chamber setup. The whole-cell patch-clamp technique was used to determine the effect of kaempferol on potassium channels in porcine coronary artery smooth muscle cells (PCASMCs). At a concentration without direct effect on vascular tone, kaempferol (3 × 10(-6) M) enhanced relaxations produced by bradykinin and sodium nitroprusside. The potentiation by kaempferol of the bradykinin-induced relaxation was not affected by N(ω)-nitro-L-arginine methyl ester, an inhibitor of NO synthase (10(-4) M) or TRAM-34 plus UCL 1684, inhibitors of intermediate- and small-conductance calcium-activated potassium channels, respectively (10(-6) M each), but was abolished by tetraethylammonium chloride, a non-selective inhibitor of calcium-activated potassium channels (10(-3) M), and iberiotoxin, a selective inhibitor of large-conductance calcium-activated potassium channel (KCa 1.1; 10(-7) M). Iberiotoxin also inhibited the potentiation by kaempferol of sodium nitroprusside-induced relaxations. Kaempferol stimulated an outward-rectifying current in PCASMCs, which was abolished by iberiotoxin. The present results suggest that, in smooth muscle cells of the porcine coronary artery, kaempferol enhanced relaxations caused by endothelium-derived and exogenous NO as well as those due to endothelium-dependent hyperpolarization. This vascular effect of kaempferol involved the activation of KCa 1.1 channels. © 2015 The British Pharmacological Society.

  16. Star-shaped ZnO/Ag hybrid nanostructures for enhanced photocatalysis and antibacterial activity

    Energy Technology Data Exchange (ETDEWEB)

    Andrade, George R.S., E-mail: grsandrade@hotmail.com [Postgraduate Program in Materials Science and Engineering, Federal University of Sergipe, São Cristóvão, SE (Brazil); Nascimento, Cristiane C. [Postgraduate Program in Materials Science and Engineering, Federal University of Sergipe, São Cristóvão, SE (Brazil); Federal Institute of Education, Science and Technology of Sergipe, Glória Campus, Nossa Senhora da Glória, SE (Brazil); Lima, Zenon M. [Postgraduate Program in Industrial Biochemistry, Tiradentes University, Aracaju, SE (Brazil); Teixeira-Neto, Erico [LNNano − Brazilian Nanotechnology National Laboratory, Brazilian Center for Research in Energy and Materials, Campinas, SP (Brazil); Costa, Luiz P. [Postgraduate Program in Industrial Biochemistry, Tiradentes University, Aracaju, SE (Brazil); ITPS − Technological and Research Institute of Sergipe, Aracaju, SE (Brazil); Gimenez, Iara F. [Postgraduate Program in Materials Science and Engineering, Federal University of Sergipe, São Cristóvão, SE (Brazil); Department of Chemistry, Federal University of Sergipe, São Cristóvão, SE (Brazil)

    2017-03-31

    Highlights: • A new and simple one-pot method for preparing star-shaped ZnO particles was reported. • ZnO particles were decorated with Ag nanoparticles (SNPs) by a photodeposition method. • The presence of SNC{sup −} ions on ZnO surface prevented uncontrollable growth of SNPs. • ZnO/Ag particles showed plasmon-enhanced photocatalytic activity toward an AZO dye. • SNP improved 16 times the antibacterial activity of ZnO toward 4 bacterial strains. - Abstract: Zinc oxide (ZnO) particles with a star-shaped morphology have been synthesized by a novel and simple room-temperature method and decorated with silver nanoparticles (SNPs) for enhanced photocatalysis and bactericide applications. The presence of thiourea during the precipitation of ZnO in alkaline conditions allowed the control of morphological features (e.g. average size and shape) and the surface functionalization with thiocyanate ions (SCN{sup −}). SNPs were deposited into the ZnO surface by a photoreduction method and their sizes could be easily controlled by changing the ZnO/AgNO{sub 3} ratio. The presence of SCN{sup −} on the semiconductor surface prevents uncontrollable growth of Ag nanoparticles into different morphologies and high degrees of polydispersity. XRD, SEM, TEM, FTIR, UV-vis-NIR and PL were employed for characterizing the structure, morphology and optical properties of the as-obtained pure and hybrid nanostructures. Finally, the hybrid ZnO/Ag particles have shown plasmon-enhanced performance for applications in photocatalysis and antibacterial activity compared to the pure ZnO counterpart. In this work, evaluation of the photodegradation of an aqueous methylene blue solution under UV-A irradiation and the antibacterial activity toward 4 bacterial strains, including Gram-positive bacteria Staphylococcus aureus (ATCC 43300, ATCC 25923 and ATCC 33591) and Gram-negative bacteria Pseudomonas aeruginosa (ATCC 27853).

  17. Enhanced exo-inulinase activity and stability by fusion of an inulin-binding module.

    Science.gov (United States)

    Zhou, Shun-Hua; Liu, Yuan; Zhao, Yu-Juan; Chi, Zhe; Chi, Zhen-Ming; Liu, Guang-Lei

    2016-09-01

    In this study, an inulin-binding module from Bacillus macerans was successfully fused to an exo-inulinase from Kluyveromyces marxianus, creating a hybrid functional enzyme. The recombinant exo-inulinase (rINU), the hybrid enzyme (rINUIBM), and the recombinant inulin-binding module (rIBM) were, respectively, heterologously expressed and biochemically characterized. It was found that both the inulinase activity and the catalytic efficiency (k cat/K m(app)) of the rINUIBM were considerably higher than those of rINU. Though the rINU and the rINUIBM shared the same optimum pH of 4.5, the optimum temperature of the rINUIBM (60 °C) was 5 °C higher than that of the rINU. Notably, the fused IBM significantly enhanced both the pH stability and the thermostability of the rINUIBM, suggesting that the rINUIBM obtained would have more extensive potential applications. Furthermore, the fusion of the IBM could substantially improve the inulin-binding capability of the rINUIBM, which was consistent with the determination of the K m(app). This meant that the fused IBM could play a critical role in the recognition of polysaccharides and enhanced the hydrolase activity of the associated inulinase by increasing enzyme-substrate proximity. Besides, the extra supplement of the independent non-catalytic rIBM could also improve the inulinase activity of the rINU. However, this improvement was much better in case of the fusion. Consequently, the IBM could be designated as a multifunctional domain that was responsible for the activity enhancement, the stabilization, and the substrate binding of the rINUIBM. All these features obtained in this study make the rINUIBM become an attractive candidate for an efficient inulin hydrolysis.

  18. MAML1 enhances the transcriptional activity of Runx2 and plays a role in bone development.

    Directory of Open Access Journals (Sweden)

    Takashi Watanabe

    Full Text Available Mastermind-like 1 (MAML1 is a transcriptional co-activator in the Notch signaling pathway. Recently, however, several reports revealed novel and unique roles for MAML1 that are independent of the Notch signaling pathway. We found that MAML1 enhances the transcriptional activity of runt-related transcription factor 2 (Runx2, a transcription factor essential for osteoblastic differentiation and chondrocyte proliferation and maturation. MAML1 significantly enhanced the Runx2-mediated transcription of the p6OSE2-Luc reporter, in which luciferase expression was controlled by six copies of the osteoblast specific element 2 (OSE2 from the Runx2-regulated osteocalcin gene promoter. Interestingly, a deletion mutant of MAML1 lacking the N-terminal Notch-binding domain also enhanced Runx2-mediated transcription. Moreover, inhibition of Notch signaling did not affect the action of MAML1 on Runx2, suggesting that the activation of Runx2 by MAML1 may be caused in a Notch-independent manner. Overexpression of MAML1 transiently enhanced the Runx2-mediated expression of alkaline phosphatase, an early marker of osteoblast differentiation, in the murine pluripotent mesenchymal cell line C3H10T1/2. MAML1(-/- embryos at embryonic day 16.5 (E16.5 had shorter bone lengths than wild-type embryos. The area of primary spongiosa of the femoral diaphysis was narrowed. At E14.5, extended zone of collagen type II alpha 1 (Col2a1 and Sox9 expression, markers of chondrocyte differentiation, and decreased zone of collagen type X alpha 1 (Col10a1 expression, a marker of hypertrophic chondrocyte, were observed. These observations suggest that chondrocyte maturation was impaired in MAML1(-/- mice. MAML1 enhances the transcriptional activity of Runx2 and plays a role in bone development.

  19. CAMKII activation is not required for maintenance of learning-induced enhancement of neuronal excitability.

    Directory of Open Access Journals (Sweden)

    Ori Liraz

    Full Text Available Pyramidal neurons in the piriform cortex from olfactory-discrimination trained rats show enhanced intrinsic neuronal excitability that lasts for several days after learning. Such enhanced intrinsic excitability is mediated by long-term reduction in the post-burst after-hyperpolarization (AHP which is generated by repetitive spike firing. AHP reduction is due to decreased conductance of a calcium-dependent potassium current, the sI(AHP. We have previously shown that learning-induced AHP reduction is maintained by persistent protein kinase C (PKC and extracellular regulated kinase (ERK activation. However, the molecular machinery underlying this long-lasting modulation of intrinsic excitability is yet to be fully described. Here we examine whether the CaMKII, which is known to be crucial in learning, memory and synaptic plasticity processes, is instrumental for the maintenance of learning-induced AHP reduction. KN93, that selectively blocks CaMKII autophosphorylation at Thr286, reduced the AHP in neurons from trained and control rat to the same extent. Consequently, the differences in AHP amplitude and neuronal adaptation between neurons from trained rats and controls remained. Accordingly, the level of activated CaMKII was similar in pirifrom cortex samples taken form trained and control rats. Our data show that although CaMKII modulates the amplitude of AHP of pyramidal neurons in the piriform cortex, its activation is not required for maintaining learning-induced enhancement of neuronal excitability.

  20. Construction of rat beta defensin-2 eukaryotic expression vector and expression in the transfected rat corneal epithelial cell

    Directory of Open Access Journals (Sweden)

    Jing Dan

    2017-03-01

    Full Text Available AIM: To construct a recombinant eukaryotic expression vector of rat beta defensin-2(rBD-2, transfect it into the rat corneal epithelial cells with lipofection, determine the expression of target gene in the transfected cells, and discuss the potentiality of recombinant plasmid expressed in corneal epithelial cells, hoping to provide an experimental foundation for further study on the antimicrobial activity of rBD-2 in vitro and in vivo and to assess the probability of defensins as a new application for infectious corneal diseases in the future. METHODS: The synthetic rBD-2 DNA fragment was inserted between the XhoI and BamHI restriction enzyme cutting sites of eukaryotic expression vector pIRES2-ZsGreen1 to construct the recombinant plasmid pIRES2-ZsGreen1-rBD-2, then transformed it into E.coli DH5α, positive clones were screened by kanamycin and identified with restriction endonucleases and sequencing analysis. Transfection into the rat corneal epithelial cells was performed by lipofection. Then the experiment was divided into three groups: rat corneal epithelial cell was transfected with the recombinant plasmid pIRES2- ZsGreen1-rBD-2, rat corneal epithelial cell was transfected with the empty plasmid pIRES2-ZsGreen1 and the non-transfected group. The inverted fluorescence microscope was used to observe the transfection process. At last, the level of rBD-2 mRNA expressed in the transfected cells and the control groups are compared by the real-time fluoresence relative quantitative PCR. RESULTS: The recombinant eukaryotic expression vector of pIRES2-ZsGreen1-rBD-2 was successfully constructed. The level of rBD-2 mRNA in transfected cells was significantly higher than that in control groups through the real-time fluorescence relative quantitative PCR. CONCLUSION: The recombinant eukaryotic expression vector pIRES2-ZsGreen1-rBD-2 could be transfected into rat corneal epithelial cells, and exogenous rBD-2 gene could be transcripted into mRNA in

  1. Exploration of the Role of Heat Activation in Enhancing Serpentine Carbon Sequestration Reactions

    International Nuclear Information System (INIS)

    McKelvy, M.J.; Chizmeshya, A.V.G.; Diefenbacher, J.; Bearat, H.; Wolf, G.

    2005-01-01

    As compared with other candidate carbon sequestration technologies, mineral carbonation offers the unique advantage of permanent disposal via geologically stable and environmentally benign carbonates. The primary challenge is the development of an economically viable process. Enhancing feedstock carbonation reactivity is key. Heat activation dramatically enhances aqueous serpentine carbonation reactivity. Although the present process is too expensive to implement, the materials characteristics and mechanisms that enhance carbonation are of keen interest for further reducing cost. Simultaneous thermogravimetric and differential thermal analysis (TGA/DTA) of the serpentine mineral lizardite was used to isolate a series of heat-activated materials as a function of residual hydroxide content at progressively higher temperatures. Their structure and composition are evaluated via TGA/DTA, X-ray powder diffraction (including phase analysis), and infrared analysis. The meta-serpentine materials that were observed to form ranged from those with longer range ordering, consistent with diffuse stage-2 like interlamellar order, to an amorphous component that preferentially forms at higher temperatures. The aqueous carbonation reaction process was investigated for representative materials via in situ synchrotron X-ray diffraction. Magnesite was observed to form directly at 15 MPa CO 2 and at temperatures ranging from 100 to 125 C. Carbonation reactivity is generally correlated with the extent of meta-serpentine formation and structural disorder.

  2. Enhanced electrochemomechanical activity of polyaniline films towards high pH region: contribution of Donnan effect

    International Nuclear Information System (INIS)

    Takashima, Wataru; Nakashima, Megumi; Pandey, Shyam S.; Kaneto, Keiichi

    2004-01-01

    Enhancement of electrochemomechanical deformation (ECMD) and expansion of ECMD activity towards high pH have been simultaneously achieved in the electrolytes equilibrated with HCl and NaCl solutions for polyaniline (PANI) film. The maximum deformation has been reached to 6.7% in the mixture of 3 M HCl and 3 M NaCl equilibrated at pH 3 at ambient temperature. By comparing the fact that the ECMD magnitude is 3.2% in 1 M HCl equilibrated at pH 0.5, the simple judicious selection of electrolyte condition leads to the enhancement of ECMD magnitude by around two times. The concentration dependence on both electrical conductivity and absorption spectra elucidates the increase of protonation ratio as a function of electrolyte concentration. The results indicate that the high concentration retains both the electrochemical and ECMD activities in PANI film towards high pH region, which is the enhanced functionality of PANI supported by Donnan effect

  3. Oligo-carrageenan kappa increases NADPH, ascorbate and glutathione syntheses and TRR/TRX activities enhancing photosynthesis, basal metabolism, and growth in Eucalyptus trees.

    Science.gov (United States)

    González, Alberto; Moenne, Fabiola; Gómez, Melissa; Sáez, Claudio A; Contreras, Rodrigo A; Moenne, Alejandra

    2014-01-01

    In order to analyze the effect of OC kappa in redox status, photosynthesis, basal metabolism and growth in Eucalyptus globulus, trees were treated with water (control), with OC kappa at 1 mg mL(-1), or treated with inhibitors of NAD(P)H, ascorbate (ASC), and glutathione (GSH) syntheses and thioredoxin reductase (TRR) activity, CHS-828, lycorine, buthionine sulfoximine (BSO), and auranofin, respectively, and with OC kappa, and cultivated for 4 months. Treatment with OC kappa induced an increase in NADPH, ASC, and GSH syntheses, TRR and thioredoxin (TRX) activities, photosynthesis, growth and activities of basal metabolism enzymes such as rubisco, glutamine synthetase (GlnS), adenosine 5'-phosphosulfate reductase (APR), involved in C, N, and S assimilation, respectively, Krebs cycle and purine/pyrimidine synthesis enzymes. Treatment with inhibitors and OC kappa showed that increases in ASC, GSH, and TRR/TRX enhanced NADPH synthesis, increases in NADPH and TRR/TRX enhanced ASC and GSH syntheses, and only the increase in NADPH enhanced TRR/TRX activities. In addition, the increase in NADPH, ASC, GSH, and TRR/TRX enhanced photosynthesis and growth. Moreover, the increase in NADPH, ASC and TRR/TRX enhanced activities of rubisco, Krebs cycle, and purine/pyrimidine synthesis enzymes, the increase in GSH, NADPH, and TRR/TRX enhanced APR activity, and the increase in NADPH and TRR/TRX enhanced GlnS activity. Thus, OC kappa increases NADPH, ASC, and GSH syntheses leading to a more reducing redox status, the increase in NADPH, ASC, GSH syntheses, and TRR/TRX activities are cross-talking events leading to activation of photosynthesis, basal metabolism, and growth in Eucalyptus trees.

  4. Oligo-carrageenan kappa increases NADPH, ascorbate and glutathione syntheses and TRR/TRX activities enhancing photosynthesis, basal metabolism, and growth in Eucalyptus trees

    Directory of Open Access Journals (Sweden)

    Alberto eGonzález

    2014-10-01

    Full Text Available In order to analyze the effect of OC kappa in redox status, photosynthesis, basal metabolism and growth in Eucalyptus globulus, trees were treated with water (control, with OC kappa at 1 mg mL-1, or treated with inhibitors of NAD(PH, ascorbate (ASC and glutathione (GSH syntheses and thioredoxin reductase (TRR activity, CHS-828, lycorine, buthionine sulfoximine (BSO and auranofin, respectively, and with OC kappa, and cultivated for 4 months. Treatment with OC kappa induced an increase in NADPH, ASC, and GSH syntheses, TRR and thioredoxin (TRX activities, photosynthesis, growth and activities of basal metabolism enzymes such as rubisco, glutamine synthetase (GlnS, adenosine 5´-phosphosulfate reductase (APR, involved in C, N and S assimilation, respectively, Krebs cycle and purine/pyrimidine synthesis enzymes. Treatment with inhibitors and OC kappa showed that increases in ASC, GSH and TRR/TRX enhanced NADPH synthesis, increases in NADPH and TRR/TRX enhanced ASC and GSH syntheses, and only the increase in NADPH enhanced TRR/TRX activities. In addition, the increase in NADPH, ASC, GSH and TRR/TRX enhanced photosynthesis and growth. Moreover, the increase in NADPH, ASC and TRR/TRX enhanced activities of rubisco, Krebs cycle and purine/pyrimidine synthesis enzymes, the increase in GSH, NADPH, and TRR/TRX enhanced APR activity, and the increase in NADPH and TRR/TRX enhanced GlnS activity. Thus, OC kappa increases NADPH, ASC and GSH syntheses leading to a more reducing redox status, the increase in NADPH, ASC, GSH syntheses and TRR/TRX activities are cross-talking events leading to activation of photosynthesis, basal metabolism and growth in Eucalyptus trees.

  5. Aged refuse enhances anaerobic digestion of waste activated sludge.

    Science.gov (United States)

    Zhao, Jianwei; Gui, Lin; Wang, Qilin; Liu, Yiwen; Wang, Dongbo; Ni, Bing-Jie; Li, Xiaoming; Xu, Rui; Zeng, Guangming; Yang, Qi

    2017-10-15

    In this work, a low-cost alternative approach (i.e., adding aged refuse (AR) into waste activated sludge) to significantly enhance anaerobic digestion of sludge was reported. Experimental results showed that with the addition dosage of AR increasing from 0 to 400 mg/g dry sludge soluble chemical oxygen demand (COD) increased from 1150 to 5240 mg/L at the digestion time of 5 d, while the maximal production of volatile fatty acids (VFA) increased from 82.6 to 183.9 mg COD/g volatile suspended solids. Although further increase of AR addition decreased the concentrations of both soluble COD and VFA, their contents in these systems with AR addition at any concentration investigated were still higher than those in the blank, which resulted in higher methane yields in these systems. Mechanism studies revealed that pertinent addition of AR promoted solubilization, hydrolysis, and acidogenesis processes and did not affect methanogenesis significantly. It was found that varieties of enzymes and anaerobes in AR were primary reason for the enhancement of anaerobic digestion. Humic substances in AR benefited hydrolysis and acidogenesis but inhibited methanogenesis. The effect of heavy metals in AR on sludge anaerobic digestion was dosage dependent. Sludge anaerobic digestion was enhanced by appropriate amounts of heavy metals but inhibited by excessive amounts of heavy metals. The relative abundances of microorganisms responsible for sludge hydrolysis and acidogenesis were also observed to be improved in the system with AR addition, which was consistent with the performance of anaerobic digestion. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Mechanism, kinetics and application studies on enhanced activated sludge by interior microelectrolysis.

    Science.gov (United States)

    Yang, Xiaoyi; Xue, Yu; Wang, Wenna

    2009-01-01

    Enhanced activated sludge by interior microelectrolysis (EAIM) was studied to treat textile wastewater, kinetics, mechanism and application of which were also discussed in comparison with traditional activated sludge and interior microelectrolysis, respectively. The results of kinetics study indicated three different processes all followed first-order kinetics well. In EAIM, three impact factors take effects on COD removal, which are flocculation, activated sludge and electrophoresis and redox. In terms of assumption of no interaction among three COD removal mechanisms, 49.6% of the total COD removal is ascribed to flocculation, 30.1% to activated sludge and 20.3% to electrophoresis and redox. EAIM showed its advantages in COD removal efficiency, extensive adaptability to complex composition and wide range of pH. EAIM-aerobic process provided an efficient and economic performance for dealing with textile wastewater.

  7. Active music classes in infancy enhance musical, communicative and social development.

    Science.gov (United States)

    Gerry, David; Unrau, Andrea; Trainor, Laurel J

    2012-05-01

    Previous studies suggest that musical training in children can positively affect various aspects of development. However, it remains unknown as to how early in development musical experience can have an effect, the nature of any such effects, and whether different types of music experience affect development differently. We found that random assignment to 6 months of active participatory musical experience beginning at 6 months of age accelerates acquisition of culture-specific knowledge of Western tonality in comparison to a similar amount of passive exposure to music. Furthermore, infants assigned to the active musical experience showed superior development of prelinguistic communicative gestures and social behaviour compared to infants assigned to the passive musical experience. These results indicate that (1) infants can engage in meaningful musical training when appropriate pedagogical approaches are used, (2) active musical participation in infancy enhances culture-specific musical acquisition, and (3) active musical participation in infancy impacts social and communication development. © 2012 Blackwell Publishing Ltd.

  8. Enhanced photocatalytic activity of ZnO–graphene nanocomposites prepared by microwave synthesis

    International Nuclear Information System (INIS)

    Herring, Natalie P.; Almahoudi, Serial H.; Olson, Chelsea R.; El-Shall, M. Samy

    2012-01-01

    This work reports a simple one-step synthesis of ZnO nanopyramids supported on reduced graphene oxide (RGO) nanosheets using microwave irradiation (MWI) of zinc acetate and GO in the presence of a mixture of oleic acid and oleylamine. The rapid decomposition of zinc acetate by MWI in the presence of the mixture of oleic acid and oleylamine results in the formation of hexagonal ZnO nanopyramids. GO has a high affinity for absorbing MWI, which results in a high local heating effect around the GO nanosheets and facilitates the reduction of GO by the oleylamine. The RGO nanosheets act as heterogeneous surface sites for the nucleation and growth of the ZnO nanopyramids. Using ligand exchange, the ZnO–RGO nanocomposites can be dispersed in an aqueous medium, thus allowing their use as photocatalysts for the degradation of the malachite green dye in water. The ZnO–RGO nanocomposites show enhanced photocatalytic activity for the degradation of the dye over the unsupported ZnO nanopyramids. The enhanced activity is attributed to efficient charge transfer of the photogenerated electrons in the conduction band of ZnO to graphene. This enhances the oxidative pathway of the holes generated in the valence band of ZnO which can effectively lead to the degradation and mineralization of the malachite green. The ZnO nanopyramids supported on RGO could have improved performance in other photocatalytic reactions and also in solar energy conversion.

  9. Gemcitabine enhances cell invasion via activating HAb18G/CD147-EGFR-pSTAT3 signaling.

    Science.gov (United States)

    Xu, Bao-Qing; Fu, Zhi-Guang; Meng, Yao; Wu, Xiao-Qing; Wu, Bo; Xu, Liang; Jiang, Jian-Li; Li, Ling; Chen, Zhi-Nan

    2016-09-20

    Pancreatic cancer, one of the most lethal cancers, has very poor 5-year survival partly due to gemcitabine resistance. Recently, it was reported that chemotherapeutic agents may act as stressors to induce adaptive responses and to promote chemoresistance in cancer cells. During long-term drug treatment, the minority of cancer cells survive and acquire an epithelial-mesenchymal transition phenotype with increased chemo-resistance and metastasis. However, the short-term response of most cancer cells remains unclear. This study aimed to investigate the short-term response of pancreatic cancer cells to gemcitabine stress and to explore the corresponding mechanism. Our results showed that gemcitabine treatment for 24 hours enhanced pancreatic cancer cell invasion. In gemcitabine-treated cells, HAb18G/CD147 was up-regulated; and HAb18G/CD147 down-regulation or inhibition attenuated gemcitabine-enhanced invasion. Mechanistically, HAb18G/CD147 promoted gemcitabine-enhanced invasion by activating the EGFR (epidermal growth factor receptor)-STAT3 (signal transducer and activator of transcription 3) signaling pathway. Inhibition of EGFR-STAT3 signaling counteracted gemcitabine-enhanced invasion, and which relied on HAb18G/CD147 levels. In pancreatic cancer tissues, EGFR was highly expressed and positively correlated with HAb18G/CD147. These data indicate that pancreatic cancer cells enhance cell invasion via activating HAb18G/CD147-EGFR-pSTAT3 signaling. Our findings suggest that inhibiting HAb18G/CD147 is a potential strategy for overcoming drug stress-associated resistance in pancreatic cancer.

  10. Infrared Analysis Of Enzymes Adsorbed Onto Model Surfaces

    Science.gov (United States)

    Story, Gloria M.; Rauch, Deborah S.; Brode, Philip F.; Marcott, Curtis A.

    1989-12-01

    The adsorption of the enzymes, subtilisin BPN' and lysozyme, onto model surfaces was examined using attenuated total reflectance (ATR) infrared (IR) spectroscopy. Using a cylindrical internal reflection (CIRcle) cell with a Germanium (Ge) internal reflection element (IRE), model hydrophilic surfaces were made by plasma cleaning the IRE and model hydrophobic surfaces were made by precoating the IRE with a thin film of polystyrene. Gas chromatography (GC)-IR data collection software was used to monitor adsorption kinetics during the first five minutes after injection of the enzyme into the CIRcle cell. It was found that for both lysozyme and BPN', most of the enzyme that was going to adsorb onto the model surface did so within ten seconds after injection. Nearly an order-of-magnitude more BPN' adsorbed on the hydrophobic Ge surface than the hydrophilic one, while lysozyme adsorbed somewhat more strongly to the hydrophilic Ge surface. Overnight, the lysozyme layer continued to increase in thickness, while BPN' maintained its initial coverage. The appearance of carboxylate bands in some of the adsorbed BPN' spectra suggests the occurrence of peptide bond hydrolysis. A Au/Pd coating on the CIRcle cell o-rings had a significant effect on the adsorption of BPN'. (This coating was applied in an attempt to eliminate interfering Teflon absorption bands.) An apparent electrochemical reaction occurred, involving BPN', Ge, Au/Pd, and the salt solution used to stabilize BPN'. The result of this reaction was enhanced adsorption of the enzyme around the coated o-rings, etching of the Ge IRE at the o-ring site, and some autolysis of the enzyme. No such reaction was observed with lysozyme.

  11. Plant carbohydrate binding module enhances activity of hybrid microbial cellulase enzyme

    Directory of Open Access Journals (Sweden)

    Caitlin Siobhan Byrt

    2012-11-01

    Full Text Available A synthetic, highly active cellulase enzyme suitable for in planta production may be a valuable tool for biotechnological approaches to develop transgenic biofuel crops with improved digestibility. Here, we demonstrate that the addition of a plant derived carbohydrate binding module (CBM to a synthetic glycosyl hydrolase (GH improved the activity of the hydrolase in releasing sugar from plant biomass. A CEL-HYB1-CBM enzyme was generated by fusing a hybrid microbial cellulase, CEL-HYB1, with the carbohydrate-binding module (CBM of the tomato (Solanum lycopersicum SlCel9C1 cellulase. CEL-HYB1 and CEL-HYB1-CBM enzymes were produced in vitro using Pichia pastoris and the activity of these enzymes was tested using CMC, MUC and native crystalline cellulose assays. The presence of the CBM substantially improved the endo-glucanase activity of CEL-HYB1, especially against the native crystalline cellulose encountered in Sorghum plant cell walls. These results indicate that addition of an endogenous plant derived CBM to cellulase enzymes may enhance hydrolytic activity.

  12. AMPK activation enhances the anti-atherogenic effects of high density lipoproteins in apoE-/- mice.

    Science.gov (United States)

    Ma, Ang; Wang, Jing; Yang, Liu; An, Yuanyuan; Zhu, Haibo

    2017-08-01

    HDL plays crucial roles at multiple stages of the pathogenesis of atherosclerosis. AMP-activated protein kinase (AMPK) is a therapeutic candidate for the treatment of cardiovascular disease. However, the effect of AMPK activation on HDL functionality has not been established in vivo. We assessed the effects of pharmacological AMPK activation using A-769662, AICAR, metformin, and IMM-H007 on the atheroprotective functions of HDL in apoE-deficient (apoE -/- ) mice fed with a high-fat diet. After administration, there were no changes in serum lipid levels among the groups. However, mice treated with AMPK activators showed significantly enhanced reverse cholesterol transport in vivo and in vitro. AMPK activation also increased the expression of ABCA1 and ABCG1 in macrophages and scavenger receptor class B type I and LCAT in the liver. HDL from AMPK activation mice exhibited lower HDL inflammatory index and myeloperoxidase activity and higher paraoxonase 1 activity than HDL from untreated mice, implying superior antioxidant and anti-inflammatory capacities. Pharmacological AMPK activation also induced polarization of macrophages to the M2 state and reduced plasma lipid peroxidation, inflammatory cytokine production, and atherosclerotic plaque formation in apoE -/- mice. These observations suggest that pharmacological AMPK activation enhances the anti-atherogenic properties of HDL in vivo. This likely represents a key mechanism by which AMPK activation attenuates atherosclerosis. Copyright © 2017 by the American Society for Biochemistry and Molecular Biology, Inc.

  13. Chicago section activities to enhance public acceptance of nuclear power

    International Nuclear Information System (INIS)

    Snyder, T.L.; Keffer, J.W.

    1992-01-01

    The Chicago section of the American Nuclear Society (ANS) is an active organization with ∼450 members. The local section territory encompasses northern Illinois and includes in its territory all six of Commonwealth Edison Company's (CECo's) nuclear generating stations as well as Argonne National Laboratory (ANL). Included in the territory are several large engineering firms - ABB Impell, Bechtel, Fluor Daniel, and Sargent ampersand Lundy. The national headquarters of the ANS is also located within the local section boundaries. All these organizations are represented in the local section membership and provide access to abundant technical resources that can be used to enhance public acceptance of nuclear power. An important attribute of any local section that enables it to perform interesting programs and be active in the community is its financial resources. The Chicago section has a strong financial base because of its ability to raise funds by participating in and sponsoring ANS topical and other meetings. For instance, in 1991, they sponsored and were actively involved in the Emergency Preparedness Topical Meeting held in Chicago. In 1992, they were actively involved in sponsoring the organizational activities of the ANS/ENS International Meeting, which will celebrate the 50th year of nuclear fission. The financial and technical resources of the Chicago section continue to contribute to a successful program of public education and public acceptance activities regarding the nuclear industry

  14. [High-level expression of heterologous protein based on increased copy number in Saccharomyces cerevisiae].

    Science.gov (United States)

    Zhang, Xinjie; He, Peng; Tao, Yong; Yang, Yi

    2013-11-04

    High-level expression system of heterologous protein mediated by internal ribosome entry site (IRES) in Saccharomyces cerevisiae was constructed, which could be used for other applications of S. cerevisiae in metabolic engineering. We constructed co-expression cassette (promoter-mCherry-TIF4631 IRES-URA3) containing promoters Pilv5, Padh2 and Ptdh3 and recombined the co-expression cassette into the genome of W303-1B-A. The URA3+ transformants were selected. By comparing the difference in the mean florescence value of mCherry in transformants, the effect of three promoters was detected in the co-expression cassette. The copy numbers of the interested genes in the genome were determined by Real-Time PCR. We analyzed genetic stability by continuous subculturing transformants in the absence of selection pressure. To verify the application of co-expression cassette, the ORF of mCherry was replaced by beta-galactosidase (LACZ) and xylose reductase (XYL1). The enzyme activities and production of beta-galactosidase and xylose reductase were detected. mCherry has been expressed in the highest-level in transformants with co-expression cassette containing Pilv5 promoter. The highest copy number of DNA fragment integrating in the genome was 47 in transformants containing Pilv5. The engineering strains showed good genetic stability. Xylose reductase was successfully expressed in the co-expression cassette containing Pilv5 promoter and TIF4631 IRES. The highest enzyme activity was 0. 209 U/mg crude protein in the transformants WIX-10. Beta-galactosidase was also expressed successfully. The transformants that had the highest enzyme activity was WIL-1 and the enzyme activity was 12.58 U/mg crude protein. The system mediated by Pilv5 promoter and TIF4631 IRES could express heterologous protein efficiently in S. cerevisiae. This study offered a new strategy for expression of heterologous protein in S. cerevisiae and provided sufficient experimental evidence for metabolic engineering

  15. Inhibition of enterovirus 71 infection by antisense octaguanidinium dendrimer-conjugated morpholino oligomers.

    Science.gov (United States)

    Tan, Chee Wah; Chan, Yoke Fun; Quah, Yi Wan; Poh, Chit Laa

    2014-07-01

    Enterovirus 71 (EV-71) infections are generally manifested as mild hand, foot and mouth disease, but have been reported to cause severe neurological complications with high mortality rates. Treatment options remain limited due to the lack of antivirals. Octaguanidinium-conjugated morpholino oligomers (vivo-MOs) are single-stranded DNA-like antisense agents that can readily penetrate cells and reduce gene expression by steric blocking of complementary RNA sequences. In this study, inhibitory effects of three vivo-MOs that are complementary to the EV-71 internal ribosome entry site (IRES) and the RNA-dependent RNA polymerase (RdRP) were tested in RD cells. Vivo-MO-1 and vivo-MO-2 targeting the EV-71 IRES showed significant viral plaque reductions of 2.5 and 3.5 log10PFU/ml, respectively. Both vivo-MOs reduced viral RNA copies and viral capsid expression in RD cells in a dose-dependent manner. In contrast, vivo-MO-3 targeting the EV-71 RdRP exhibited less antiviral activity. Both vivo-MO-1 and 2 remained active when administered either 4h before or within 6h after EV-71 infection. Vivo-MO-2 exhibited antiviral activities against poliovirus (PV) and coxsackievirus A16 but vivo-MO-1 showed no antiviral activities against PV. Both the IRES-targeting vivo-MO-1 and vivo-MO-2 inhibit EV-71 RNA translation. Resistant mutants arose after serial passages in the presence of vivo-MO-1, but none were isolated against vivo-MO-2. A single T to C substitution at nucleotide position 533 was sufficient to confer resistance to vivo-MO-1. Our findings suggest that IRES-targeting vivo-MOs are good antiviral candidates for treating early EV-71 infection, and vivo-MO-2 is a more favorable candidate with broader antiviral spectrum against enteroviruses and are refractory to antiviral resistance. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. 6-Mercaptopurine, an activator of Nur77, enhances transcriptional activity of HIF-1alpha resulting in new vessel formation.

    Science.gov (United States)

    Yoo, Y-G; Na, T-Y; Yang, W-K; Kim, H-J; Lee, I-K; Kong, G; Chung, J-H; Lee, M-O

    2007-05-31

    Hypoxia-inducible factor-1alpha (HIF-1alpha) plays a central role in oxygen homeostasis. Previously, we reported that the orphan nuclear receptor Nur77 functions in stabilizing HIF-1alpha. Here, we demonstrate that 6-mercaptopurine (6-MP), an activator of the NR4A family members, enhances transcriptional activity of HIF-1. 6-MP enhanced the protein-level of HIF-1alpha as well as vascular endothelial growth factor (VEGF) in a dose- and time-dependent manner. The induction of HIF-1alpha was abolished by the transfection of either a dominant-negative Nur77 mutant or si-Nur77, indicating a critical role of Nur77 in the 6-MP action. The HIF-1alpha protein level remained up to 60 min in the presence of 6-MP when de novo protein synthesis was blocked by cycloheximide, suggesting that 6-MP induces stabilization of the HIF-1alpha protein. The fact that 6-MP decreased the association of HIF-1alpha with von Hippel-Lindau protein and the acetylation of HIF-1alpha, may explain how 6-MP induced stability of HIF-1alpha. Further, 6-MP induced the transactivation function of HIF-1alpha by recruiting co-activator cyclic-AMP-response-element-binding protein. Finally, 6-MP enhanced the expression of HIF-1alpha and VEGF, and the formation of capillary tubes in human umbilical vascular endothelial cells. Together, our results provide a new insight for 6-MP action in the stabilization of HIF-1alpha and imply a potential application of 6-MP in hypoxia-associated human vascular diseases.

  17. DNP-enhanced solid-state NMR spectroscopy of active pharmaceutical ingredients.

    Science.gov (United States)

    Zhao, Li; Pinon, Arthur C; Emsley, Lyndon; Rossini, Aaron J

    2017-11-28

    Solid-state NMR spectroscopy has become a valuable tool for the characterization of both pure and formulated active pharmaceutical ingredients (APIs). However, NMR generally suffers from poor sensitivity that often restricts NMR experiments to nuclei with favorable properties, concentrated samples, and acquisition of one-dimensional (1D) NMR spectra. Here, we review how dynamic nuclear polarization (DNP) can be applied to routinely enhance the sensitivity of solid-state NMR experiments by one to two orders of magnitude for both pure and formulated APIs. Sample preparation protocols for relayed DNP experiments and experiments on directly doped APIs are detailed. Numerical spin diffusion models illustrate the dependence of relayed DNP enhancements on the relaxation properties and particle size of the solids and can be used for particle size determination when the other factors are known. We then describe the advanced solid-state NMR experiments that have been enabled by DNP and how they provide unique insight into the molecular and macroscopic structure of APIs. For example, with large sensitivity gains provided by DNP, natural isotopic abundance, 13 C- 13 C double-quantum single-quantum homonuclear correlation NMR spectra of pure APIs can be routinely acquired. DNP also enables solid-state NMR experiments with unreceptive quadrupolar nuclei such as 2 H, 14 N, and 35 Cl that are commonly found in APIs. Applications of DNP-enhanced solid-state NMR spectroscopy for the molecular level characterization of low API load formulations such as commercial tablets and amorphous solid dispersions are described. Future perspectives for DNP-enhanced solid-state NMR experiments on APIs are briefly discussed. Copyright © 2017 John Wiley & Sons, Ltd.

  18. Effects of selenylation modification on immune-enhancing activity of garlic polysaccharide.

    Directory of Open Access Journals (Sweden)

    Shulei Qiu

    Full Text Available The garlic polysaccharide was modified by HNO3-Na2SeO3 method according to orthogonal design L9(3(4 to obtain nine selenizing garlic polysaccharides, sGPS1-sGPS9. Their effects on chicken peripheral lymphocytes proliferation in vitro were compared by MTT assay. The results showed that sGPSs could significantly promote lymphocytes proliferation, sGPS3, sGPS5 and sGPS6 presented stronger efficacy. In vivo experiment, 14-day-old chickens were injected respectively with sGPS3, sGPS5 and sGPS6 when they were vaccinated with ND vaccine taking unmodified GPS as control. The results showed that three sGPSs could significantly promote lymphocyte proliferation, enhance serum antibody titer, IFN-γ and IL-2 contents. These results indicated that selenylation modification could significantly enhance the immune-enhancing activity of GPS, sGPS6 possessed the best efficacy and could be as a candidate drug of immunoenhancer. Its optimal modification conditions were 400 mg of sodium selenite for 500 mg of GPS, reaction temperature of 70°C and reaction time of 6 h.

  19. Webcams, crowdsourcing, and enhanced crosswalks: Developing a novel method to analyze active transportation

    Directory of Open Access Journals (Sweden)

    J. Aaron eHipp

    2016-05-01

    Full Text Available Introduction: Active transportation opportunities and infrastructure are an important component of a community’s design, livability, and health. Features of the built environment influence active transportation, but objective study of the natural experiment effects of built environment improvements on active transportation is challenging. The purpose of this study was to develop and present a novel method of active transportation research using webcams and crowdsourcing, and to determine if crosswalk enhancement was associated with changes in active transportation rates, including across a variety of weather conditions. Methods: 20,529 publicly available webcam images from two street intersections in Washington, D.C., were used to examine the impact of an improved crosswalk on active transportation. A crowdsource, Amazon Mechanical Turk, annotated image data. Temperature data was collected from the National Oceanic and Atmospheric Administration, and precipitation data was annotated from images by trained research assistants. Results: Summary analyses demonstrated slight, bi-directional differences in the percent of images with pedestrians and bicyclists captured before and after the enhancement of the crosswalks. Chi-square analyses revealed these changes were not significant. In general, pedestrian presence increased in images captured during moderate temperatures compared to images captured during hot or cold temperatures. Chi-square analyses indicated the crosswalk improvement may have encouraged walking and biking in uncomfortable outdoor conditions (p<0.5. Conclusion: The methods employed provide an objective, cost-effective alternative to traditional means of examining the effects of built environment changes on active transportation. The use of webcams to collect active transportation data has applications for community policymakers, planners, and health professionals. Future research will work to validate this method in a variety of

  20. Webcams, Crowdsourcing, and Enhanced Crosswalks: Developing a Novel Method to Analyze Active Transportation.

    Science.gov (United States)

    Hipp, J Aaron; Manteiga, Alicia; Burgess, Amanda; Stylianou, Abby; Pless, Robert

    2016-01-01

    Active transportation opportunities and infrastructure are an important component of a community's design, livability, and health. Features of the built environment influence active transportation, but objective study of the natural experiment effects of built environment improvements on active transportation is challenging. The purpose of this study was to develop and present a novel method of active transportation research using webcams and crowdsourcing, and to determine if crosswalk enhancement was associated with changes in active transportation rates, including across a variety of weather conditions. The 20,529 publicly available webcam images from two street intersections in Washington, DC, USA were used to examine the impact of an improved crosswalk on active transportation. A crowdsource, Amazon Mechanical Turk, annotated image data. Temperature data were collected from the National Oceanic and Atmospheric Administration, and precipitation data were annotated from images by trained research assistants. Summary analyses demonstrated slight, bi-directional differences in the percent of images with pedestrians and bicyclists captured before and after the enhancement of the crosswalks. Chi-square analyses revealed these changes were not significant. In general, pedestrian presence increased in images captured during moderate temperatures compared to images captured during hot or cold temperatures. Chi-square analyses indicated the crosswalk improvement may have encouraged walking and biking in uncomfortable outdoor conditions (P < 0.5). The methods employed provide an objective, cost-effective alternative to traditional means of examining the effects of built environment changes on active transportation. The use of webcams to collect active transportation data has applications for community policymakers, planners, and health professionals. Future research will work to validate this method in a variety of settings as well as across different built

  1. Apitherapeutics and phage-loaded nanofibers as wound dressings with enhanced wound healing and antibacterial activity.

    Science.gov (United States)

    Sarhan, Wessam A; Azzazy, Hassan Me

    2017-09-01

    Develop green wound dressings which exhibit enhanced wound-healing ability and potent antibacterial effects. Honey, polyvinyl alcohol, chitosan nanofibers were electrospun and loaded with bee venom, propolis and/or bacteriophage against the multidrug-resistant Pseudomonas aeruginosa and examined for their antibacterial, wound-healing ability and cytotoxicity. Among different formulations of nanofibers, honey, polyvinyl alcohol, chitosan-bee venom/bacteriophage exhibited the most potent antibacterial activity against all tested bacterial strains (Gram-positive and -negative strains) and achieved nearly complete killing of multidrug-resistant P. aeruginosa. In vivo testing revealed enhanced wound-healing results and cytotoxicity testing proved improved biocompatibility. The developed biocompatible nanofibers represent competitive wound-healing dressings with potent antibacterial and wound-healing activity.

  2. Granzyme B-dependent proteolysis acts as a switch to enhance the proinflammatory activity of IL-1α.

    LENUS (Irish Health Repository)

    Afonina, Inna S

    2011-10-21

    Granzyme B is a cytotoxic lymphocyte-derived protease that plays a central role in promoting apoptosis of virus-infected target cells, through direct proteolysis and activation of constituents of the cell death machinery. However, previous studies have also implicated granzymes A and B in the production of proinflammatory cytokines, via a mechanism that remains undefined. Here we show that IL-1α is a substrate for granzyme B and that proteolysis potently enhanced the biological activity of this cytokine in vitro as well as in vivo. Consistent with this, compared with full-length IL-1α, granzyme B-processed IL-1α exhibited more potent activity as an immunoadjuvant in vivo. Furthermore, proteolysis of IL-1α within the same region, by proteases such as calpain and elastase, was also found to enhance its biological potency. Thus, IL-1α processing by multiple immune-related proteases, including granzyme B, acts as a switch to enhance the proinflammatory properties of this cytokine.

  3. 1,25D3 enhances antitumor activity of gemcitabine and cisplatin in human bladder cancer models

    Science.gov (United States)

    Ma, Yingyu; Yu, Wei-Dong; Trump, Donald L.; Johnson, Candace S.

    2010-01-01

    Background 1,25 dihydroxyvitamin D3 (1,25D3) potentiates the cytotoxic effects of several common chemotherapeutic agents. The combination of gemcitabine and cisplatin (GC) is a current standard chemotherapy regimen for bladder cancer. We investigated whether 1,25D3 could enhance the antitumor activity of GC in bladder cancer model systems. Methods Human bladder cancer T24 and UMUC3 cells were pretreated with 1,25D3 followed by GC. Apoptosis were assessed by annexin V staining. Caspase activation was examined by immunoblot analysis and substrate-based caspase activity assay. The cytotoxic effects were examined using MTT and in vitro clonogenic assay. p73 protein levels were assessed by immunoblot analysis. Knockdown of p73 was achieved by siRNA. The in vivo antitumor activity was assessed by in vivo excision clonogenic assay and tumor regrowth delay in the T24 xenograft model. Results 1,25D3 pretreatment enhanced GC-induced apoptosis and the activities of caspases- 8, 9 and 3 in T24 and UMUC3 cells. 1,25D3 synergistically reduced GC-suppressed surviving fraction in T24 cells. 1,25D3, gemcitabine, or cisplatin induced p73 accumulation, which was enhanced by GC or 1,25D3 and GC. p73 expression was lower in human primary bladder tumor tissue compared with adjacent normal tissue. Knockdown of p73 increased clonogenic capacity of T24 cells treated with 1,25D3, GC or 1,25D3 and GC. 1,25D3 and GC combination enhanced tumor regression compared with 1,25D3 or GC alone. Conclusions 1,25D3 potentiates GC-mediated growth inhibition in human bladder cancer models in vitro and in vivo, which involves p73 induction and apoptosis. PMID:20564622

  4. Collective Behavior of Chiral Active Matter: Pattern Formation and Enhanced Flocking

    Science.gov (United States)

    Liebchen, Benno; Levis, Demian

    2017-08-01

    We generalize the Vicsek model to describe the collective behavior of polar circle swimmers with local alignment interactions. While the phase transition leading to collective motion in 2D (flocking) occurs at the same interaction to noise ratio as for linear swimmers, as we show, circular motion enhances the polarization in the ordered phase (enhanced flocking) and induces secondary instabilities leading to structure formation. Slow rotations promote macroscopic droplets with late time sizes proportional to the system size (indicating phase separation) whereas fast rotations generate patterns consisting of phase synchronized microflocks with a controllable characteristic size proportional to the average single-particle swimming radius. Our results defy the viewpoint that monofrequent rotations form a vapid extension of the Vicsek model and establish a generic route to pattern formation in chiral active matter with possible applications for understanding and designing rotating microflocks.

  5. Kaempferol enhances endothelium-dependent relaxation in the porcine coronary artery through activation of large-conductance a2+-activated K+ channels

    Science.gov (United States)

    Xu, Y C; Leung, S W S; Leung, G P H; Man, R Y K

    2015-01-01

    Background and Purpose Kaempferol, a plant flavonoid present in normal human diet, can modulate vasomotor tone. The present study aimed to elucidate the signalling pathway through which this flavonoid enhanced relaxation of vascular smooth muscle. Experimental Approach The effect of kaempferol on the relaxation of porcine coronary arteries to endothelium-dependent (bradykinin) and -independent (sodium nitroprusside) relaxing agents was studied in an in vitro organ chamber setup. The whole-cell patch-clamp technique was used to determine the effect of kaempferol on potassium channels in porcine coronary artery smooth muscle cells (PCASMCs). Key Results At a concentration without direct effect on vascular tone, kaempferol (3 × 10−6 M) enhanced relaxations produced by bradykinin and sodium nitroprusside. The potentiation by kaempferol of the bradykinin-induced relaxation was not affected by Nω-nitro-L-arginine methyl ester, an inhibitor of NO synthase (10−4 M) or TRAM-34 plus UCL 1684, inhibitors of intermediate- and small-conductance calcium-activated potassium channels, respectively (10−6 M each), but was abolished by tetraethylammonium chloride, a non-selective inhibitor of calcium-activated potassium channels (10−3 M), and iberiotoxin, a selective inhibitor of large-conductance calcium-activated potassium channel (KCa1.1; 10−7 M). Iberiotoxin also inhibited the potentiation by kaempferol of sodium nitroprusside-induced relaxations. Kaempferol stimulated an outward-rectifying current in PCASMCs, which was abolished by iberiotoxin. Conclusions and Implications The present results suggest that, in smooth muscle cells of the porcine coronary artery, kaempferol enhanced relaxations caused by endothelium-derived and exogenous NO as well as those due to endothelium-dependent hyperpolarization. This vascular effect of kaempferol involved the activation of KCa1.1 channels. PMID:25652142

  6. Diatomite-immobilized BiOI hybrid photocatalyst: Facile deposition synthesis and enhanced photocatalytic activity

    Science.gov (United States)

    Li, Baoying; Huang, Hongwei; Guo, Yuxi; Zhang, Yihe

    2015-10-01

    A novel diatomite-immobilized BiOI hybrid photocatalyst has been prepared by a facile one-step deposition process for the first time. The structure, morphology and optical property of the products were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and UV-vis diffuse reflectance spectroscopy (DRS). The photocatalytic performance of the as-prepared BiOI/diatomite photocatalysts was studied by photodegradation of Rhodamine B (RhB) and methylene blue (MB) and monitoring photocurrent generation under visible light (λ > 420 nm). The results revealed that BiOI/diatomite composites exhibit enhanced photocatalytic activity compared to the pristine BiOI sample. This enhancement should be attributed to that diatomite can play as an excellent carrier platform to increase the reactive sites and promote the separation of photogenerated electron-hole pairs. In addition, the corresponding photocatalytic mechanism was proposed based on the active species trapping experiments. This work shed new light on facile fabrication of novel composite photocatalyst based on natural mineral.

  7. Curcumin induces apoptotic cell death of activated human CD4+ T cells via increasing endoplasmic reticulum stress and mitochondrial dysfunction.

    Science.gov (United States)

    Zheng, Min; Zhang, Qinggao; Joe, Yeonsoo; Lee, Bong Hee; Ryu, Do Gon; Kwon, Kang Beom; Ryter, Stefan W; Chung, Hun Taeg

    2013-03-01

    Curcumin, a natural polyphenolic antioxidant compound, exerts well-known anti-inflammatory and immunomodulatory effects, the latter which can influence the activation of immune cells including T cells. Furthermore, curcumin can inhibit the expression of pro-inflammatory cytokines and chemokines, through suppression of the NF-κB signaling pathway. The beneficial effects of curcumin in diseases such as arthritis, allergy, asthma, atherosclerosis, diabetes and cancer may be due to its immunomodulatory properties. We studied the potential of curcumin to modulate CD4+ T cells-mediated autoimmune disease, by examining the effects of this compound on human CD4+ lymphocyte activation. Stimulation of human T cells with PHA or CD3/CD28 induced IL-2 mRNA expression and activated the endoplasmic reticulum (ER) stress response. The treatment of T cells with curcumin induced the unfolded protein response (UPR) signaling pathway, initiated by the phosphorylation of PERK and IRE1. Furthermore, curcumin increased the expression of the ER stress associated transcriptional factors XBP-1, cleaved p50ATF6α and C/EBP homologous protein (CHOP) in human CD4+ and Jurkat T cells. In PHA-activated T cells, curcumin further enhanced PHA-induced CHOP expression and reduced the expression of the anti-apoptotic protein Bcl-2. Finally, curcumin treatment induced apoptotic cell death in activated T cells via eliciting an excessive ER stress response, which was reversed by the ER-stress inhibitor 4-phenylbutyric acid or transfection with CHOP-specific siRNA. These results suggest that curcumin can impact both ER stress and mitochondria functional pathways, and thereby could be used as a promising therapy in the context of Th1-mediated autoimmune diseases. Copyright © 2013 Elsevier B.V. All rights reserved.

  8. A general approach toward enhancement of pseudocapacitive performance of conducting polymers by redox-active electrolytes

    KAUST Repository

    Chen, Wei

    2014-12-01

    A general approach is demonstrated where the pseudocapacitive performance of different conducting polymers is enhanced in redox-active electrolytes. The concept is demonstrated using several electroactive conducting polymers, including polyaniline, polypyrrole, and poly(3,4-ethylenedioxythiophene). As compared to conventional electrolytes, the redox-active electrolytes, prepared by simply adding a redox mediator to the conventional electrolyte, can significantly improve the energy storage capacity of pseudocapacitors with different conducting polymers. The results show that the specific capacitance of conducting polymer based pseudocapacitors can be increased by a factor of two by utilization of the redox-active electrolytes. In fact, this approach gives some of the highest reported specific capacitance values for electroactive conducting polymers. Moreover, our findings present a general and effective approach for the enhancement of energy storage performance of pseudocapacitors using a variety of polymeric electrode materials. © 2014 Elsevier B.V. All rights reserved.

  9. Quorum Sensing Extracellular Death Peptides Enhance the Endoribonucleolytic Activities of Mycobacterium tuberculosis MazF Toxins

    Science.gov (United States)

    Nigam, Akanksha; Kumar, Sathish

    2018-01-01

    ABSTRACT mazEF is a toxin-antitoxin module located on chromosomes of most bacteria. MazF toxins are endoribonucleases antagonized by MazE antitoxins. Previously, we characterized several quorum sensing peptides called "extracellular death factors" (EDFs). When secreted from bacterial cultures, EDFs induce interspecies cell death. EDFs also enhance the endoribonucleolytic activity of Escherichia coli MazF. Mycobacterium tuberculosis carries several mazEF modules. Among them, the endoribonucleolytic activities of MazF proteins mt-1, mt-3, and mt-6 were identified. MazF-mt6 and MazF-mt-3 cleave M. tuberculosis rRNAs. Here we report the in vitro effects of EDFs on the endoribonucleolytic activities of M. tuberculosis MazFs. Escherichia coli EDF (EcEDF) and the three Pseudomonas aeruginosa EDFs (PaEDFs) individually enhance the endoribonucleolytic activities of MazF-mt6 and MazF-mt3 and overcome the inhibitory effect of MazE-mt3 or MazE-mt6 on the endoribonucleolytic activities of the respective toxins. We propose that these EDFs can serve as a basis for a novel class of antibiotics against M. tuberculosis. PMID:29717013

  10. Neuromodulation of activity-dependent synaptic enhancement at crayfish neuromuscular junction.

    Science.gov (United States)

    Qian, S M; Delaney, K R

    1997-10-17

    Action potential-evoked transmitter release is enhanced for many seconds after moderate-frequency stimulation (e.g. 15 Hz for 30 s) at the excitor motorneuron synapse of the crayfish dactyl opener muscle. Beginning about 1.5 s after a train, activity-dependent synaptic enhancement (ADSE) is dominated by a process termed augmentation (G.D. Bittner, D.A. Baxter, Synaptic plasticity at crayfish neuromuscular junctions: facilitation and augmentation, Synapse 7 (1991) 235-243'[4]; K.L. Magleby, Short-term changes in synaptic efficacy, in: G.M. Edelman, L.E. Gall, C.W. Maxwell (Eds.), Synaptic Function, John Wiley and Sons, New York, 1987, pp. 21-56; K.L. Magleby; J.E. Zengel, Augmentation: a process that acts to increase transmitter release at the frog neuromuscular junction, J. Physiol. (Lond.) 257 (1976) 449-470) which decays approximately exponentially with a time constant of about 10 s at 16 degrees C, reflecting the removal of Ca2+ which accumulates during the train in presynaptic terminals (K.R. Delaney, D.W. Tank, R.S. Zucker, Serotonin-mediated enhancement of transmission at crayfish neuromuscular junction is independent of changes in calcium, J. Neurosci. 11 (1991) 2631-2643). Serotonin (5-HT, 1 microM) increases evoked and spontaneous transmitter release several-fold (D. Dixon, H.L. Atwood, Crayfish motor nerve terminal's response to serotonin examined by intracellular microelectrode, J. Neurobiol. 16 (1985) 409-424; J. Dudel, Modulation of quantal synaptic release by serotonin and forskolin in crayfish motor nerve terminals, in: Modulation of Synaptic Transmission and Plasticity in Nervous Systems, G. Hertting, H.-C. Spatz (Eds.), Springer-Verlag, Berlin, 1988; S. Glusman, E.A. Kravitz. The action of serotonin on excitatory nerve terminals in lobster nerve-muscle preparations, J. Physiol. (Lond.) 325 (1982) 223-241). We found that ADSE persists about 2-3 times longer after moderate-frequency presynaptic stimulation in the presence of 5-HT. This slowing of the

  11. Toward Multimodal Human-Robot Interaction to Enhance Active Participation of Users in Gait Rehabilitation.

    Science.gov (United States)

    Gui, Kai; Liu, Honghai; Zhang, Dingguo

    2017-11-01

    Robotic exoskeletons for physical rehabilitation have been utilized for retraining patients suffering from paraplegia and enhancing motor recovery in recent years. However, users are not voluntarily involved in most systems. This paper aims to develop a locomotion trainer with multiple gait patterns, which can be controlled by the active motion intention of users. A multimodal human-robot interaction (HRI) system is established to enhance subject's active participation during gait rehabilitation, which includes cognitive HRI (cHRI) and physical HRI (pHRI). The cHRI adopts brain-computer interface based on steady-state visual evoked potential. The pHRI is realized via admittance control based on electromyography. A central pattern generator is utilized to produce rhythmic and continuous lower joint trajectories, and its state variables are regulated by cHRI and pHRI. A custom-made leg exoskeleton prototype with the proposed multimodal HRI is tested on healthy subjects and stroke patients. The results show that voluntary and active participation can be effectively involved to achieve various assistive gait patterns.

  12. The Start2Bike program is effective in increasing health-enhancing physical activity : A controlled study

    NARCIS (Netherlands)

    Ooms, Linda; Veenhof, Cindy; De Bakker, Dinny H.

    2017-01-01

    Background: The sports club is seen as a new relevant setting to promote health-enhancing physical activity (HEPA) among inactive population groups. Little is known about the effectiveness of strategies and activities implemented in the sports club setting on increasing HEPA levels. This study

  13. Glucose Administration Enhances fMRI Brain Activation and Connectivity Related to Episodic Memory Encoding for Neutral and Emotional Stimuli

    Science.gov (United States)

    Parent, Marise B.; Krebs-Kraft, Desiree L.; Ryan, John P.; Wilson, Jennifer S.; Harenski, Carla; Hamann, Stephan

    2011-01-01

    Glucose enhances memory in a variety of species. In humans, glucose administration enhances episodic memory encoding, although little is known regarding the neural mechanisms underlying these effects. Here we examined whether elevating blood glucose would enhance functional MRI (fMRI) activation and connectivity in brain regions associated with…

  14. Glucose administration enhances fMRI brain activation and connectivity related to episodic memory encoding for neutral and emotional stimuli.

    Science.gov (United States)

    Parent, Marise B; Krebs-Kraft, Desiree L; Ryan, John P; Wilson, Jennifer S; Harenski, Carla; Hamann, Stephan

    2011-04-01

    Glucose enhances memory in a variety of species. In humans, glucose administration enhances episodic memory encoding, although little is known regarding the neural mechanisms underlying these effects. Here we examined whether elevating blood glucose would enhance functional MRI (fMRI) activation and connectivity in brain regions associated with episodic memory encoding and whether these effects would differ depending on the emotional valence of the material. We used a double-blind, within-participants, crossover design in which either glucose (50g) or a saccharin placebo were administered before scanning, on days approximately 1 week apart. We scanned healthy young male participants with fMRI as they viewed emotionally arousing negative pictures and emotionally neutral pictures, intermixed with baseline fixation. Free recall was tested at 5 min after scanning and again after 1 day. Glucose administration increased activation in brain regions associated with successful episodic memory encoding. Glucose also enhanced activation in regions whose activity was correlated with subsequent successful recall, including the hippocampus, prefrontal cortex, and other regions, and these effects differed for negative vs. neutral stimuli. Finally, glucose substantially increased functional connectivity between the hippocampus and amygdala and a network of regions previously implicated in successful episodic memory encoding. These findings fit with evidence from nonhuman animals indicating glucose modulates memory by selectively enhancing neural activity in brain regions engaged during memory tasks. Our results highlight the modulatory effects of glucose and the importance of examining both regional changes in activity and functional connectivity to fully characterize the effects of glucose on brain function and memory. Copyright © 2011 Elsevier Ltd. All rights reserved.

  15. The picornavirus avian encephalomyelitis virus possesses a hepatitis C virus-like internal ribosome entry site element

    DEFF Research Database (Denmark)

    Bakhshesh, M.; Groppelli, E.; Willcocks, M.A.

    2008-01-01

    and it is also resistant to an inhibitor of eIF4A. These properties are reminiscent of the recently discovered class of IRES elements within certain other picornaviruses, such as porcine teschovirus 1 (PTV-1). Like the PTV-1 IRES, the AEV IRES shows significant similarity to the hepatitis C virus (HCV) IRES......Avian encephalomyelitis virus (AEV) is a picornavirus that causes disease in poultry worldwide, and flocks must be vaccinated for protection. AEV is currently classified within the hepatovirus genus, since its proteins are most closely related to those of hepatitis A virus (HAV). We now provide...

  16. Cocoa-enriched diet enhances antioxidant enzyme activity and modulates lymphocyte composition in thymus from young rats.

    Science.gov (United States)

    Ramiro-Puig, Emma; Urpí-Sardà, Mireia; Pérez-Cano, Francisco J; Franch, Angels; Castellote, Cristina; Andrés-Lacueva, Cristina; Izquierdo-Pulido, Maria; Castell, Margarida

    2007-08-08

    Cocoa is a rich source of flavonoids, mainly (-)-epicatechin, (+)-catechin, and procyanidins. This article reports the effect of continuous cocoa intake on antioxidant capacity in plasma and tissues, including lymphoid organs and liver, from young rats. Weaned Wistar rats received natural cocoa (4% or 10% food intake) for three weeks, corresponding to their infancy. Flavonoid absorption was confirmed through the quantification of epicatechin metabolites in urine. Total antioxidant capacity (TAC) and the activity of antioxidant enzymes, superoxide dismutase (SOD) and catalase, were examined. Cocoa intake enhanced TAC in all tissues especially in thymus. Moreover, thymus SOD and catalase activities were also dose-dependently increased by cocoa. It was also analyzed whether the enhanced antioxidant system in thymus could influence its cellular composition. An increase in the percentage of thymocytes in advanced development stage was found. In summary, cocoa diet enhances thymus antioxidant defenses and influences thymocyte differentiation.

  17. Characteristics and enhanced antioxidant activity of glycated Morchella esculenta protein isolate

    Directory of Open Access Journals (Sweden)

    Qiang ZHANG

    Full Text Available Abstract Morchella esculenta (L Pers. is a highly valued edible and medicinal fungus that remains underutilized. For this study, the effects of glycation treatment on antioxidant activity and characteristics of the M. esculenta protein isolate (MPI were investigated via the Maillard reaction. Conjugation between MPI and xylose was proven via UV-vis, FT-IR, intrinsic fluorescence analysis, and SDS-PAGE. Amino acid analysis revealed involvement of lysine, arginine and tyrosine in MPI, forming a covalent cross-link with xylose. Differential scanning calorimetry (DSC results showed that glycated MPI (MPIG possesses a more favorable thermal stability compared to native MPI (MPIN, heated MPI (MPIH and an unheated mixture of MPI and xylose (MPI-XM. MPIG exhibited significantly enhanced antioxidant activity compared to MPIN, MPIH, and MPI-XM. These results indicate MPIG can serve as a promising novel source of nutraceutical and functional ingredients that exert antioxidant activity.

  18. THE ROLES OF TED TALKS AND VLOG IN ENHANCING STUDENTS‘ ACTIVENESS IN SPEAKING CLASS

    Directory of Open Access Journals (Sweden)

    Candradewi Wahyu Anggraeni

    2017-12-01

    Full Text Available The aims of this research are to describe the roles of TED Talks and Vlog in enhancing students‘ activeness in speaking class and to explain the students‘ perspectives toward the use of TED Talks and Vlog in speaking class. The research method used in this research is qualitative research design in the form of case study. The instruments of data collection are documents of students‘ vlog, observation, questionnaire, and interview. The participants of this research are the students of speaking class. This research has three significances which consist of theoretical, practical, and pedagogical significances. The theoretical significance is the research contributes to prove and add the speaking theories, whereas the practical significance is the research can be conducted by teachers, lecturers, or researchers to figure out the roles and the ways to improve students‘ participation in speaking class. In addition, the pedagogical significance shows that this research provides a reference of the use TED Talks and Vlog in enhancing students‘ activeness in speaking class, helps the students to be active in speaking class by following the lecturer‘s instruction toward the speaking activities given, and can be used as the empirical research finding toward students‘ activeness in speaking class. The findings show that TED Talks and Vlog have seven roles in order to help the students to be more active in speaking class and reveal the students‘ perceptions about virtues and hurdles toward the use of TED Talks and Vlog in speaking class.

  19. Activated Integrin-Linked Kinase Negatively Regulates Muscle Cell Enhancement Factor 2C in C2C12 Cells

    Directory of Open Access Journals (Sweden)

    Zhenguo Dong

    2015-01-01

    Full Text Available Our previous study reported that muscle cell enhancement factor 2C (MEF2C was fully activated after inhibition of the phosphorylation activity of integrin-linked kinase (ILK in the skeletal muscle cells of goats. It enhanced the binding of promoter or enhancer of transcription factor related to proliferation of muscle cells and then regulated the expression of these genes. In the present investigation, we explored whether ILK activation depended on PI3K to regulate the phosphorylation and transcriptional activity of MEF2C during C2C12 cell proliferation. We inhibited PI3K activity in C2C12 with LY294002 and then found that ILK phosphorylation levels and MEF2C phosphorylation were decreased and that MCK mRNA expression was suppressed significantly. After inhibiting ILK phosphorylation activity with Cpd22 and ILK-shRNA, we found MEF2C phosphorylation activity and MCK mRNA expression were increased extremely significantly. In the presence of Cpd22, PI3K activity inhibition increased MEF2C phosphorylation and MCK mRNA expression indistinctively. We conclude that ILK negatively and independently of PI3K regulated MEF2C phosphorylation activity and MCK mRNA expression in C2C12 cells. The results provide new ideas for the study of classical signaling pathway of PI3K-ILK-related proteins and transcription factors.

  20. A general approach toward enhancement of pseudocapacitive performance of conducting polymers by redox-active electrolytes

    KAUST Repository

    Chen, Wei; Xia, Chuan; Baby, Rakhi Raghavan; Alshareef, Husam N.

    2014-01-01

    A general approach is demonstrated where the pseudocapacitive performance of different conducting polymers is enhanced in redox-active electrolytes. The concept is demonstrated using several electroactive conducting polymers, including polyaniline

  1. Fish-Free Diet in Patients with Phenylketonuria Is Not Associated with Early Atherosclerotic Changes and Enhanced Platelet Activation.

    Directory of Open Access Journals (Sweden)

    Patrik Htun

    Full Text Available Since patients with phenylketonuria (PKU have to follow a lifelong restriction of natural protein to lower phenylalanine-intake, they never eat fish. This diet may lead to a chronic deficit of omega-3 and omega-6 fatty acids with the risk of early atherosclerotic changes. The aim of the study was to analyse the fatty acid profile of PKU patients and to correlate the results with surrogate markers of early atherosclerotic changes [enhanced carotid intima media thickness (CIMT and ß-stiffness index] and platelet activation.In 43 PKU patients and in 58 healthy controls we prospectively examined the fatty acid profile, CIMT, ß-stiffness index and platelet activation (flow cytometric determination of markers of platelet activation. CIMT was measured bilaterally by ultrasound. CIMTmean was defined as the mean value of the sum of CIMTleft and CIMTright.Despite of lower HDL-cholesterol and higher triglyceride concentrations in the PKU group, there was no significant difference in the omega-6 or omega-3 fatty acid profile, CIMT, ß-stiffness index between both groups. Platelet activation was not enhanced in the PKU group.Fish-free diet does not induce early atherosclerotic changes or enhanced platelet activation in PKU patients.

  2. Fish-Free Diet in Patients with Phenylketonuria Is Not Associated with Early Atherosclerotic Changes and Enhanced Platelet Activation.

    Science.gov (United States)

    Htun, Patrik; Nee, Jens; Ploeckinger, Ursula; Eder, Klaus; Geisler, Tobias; Gawaz, Meinrad; Bocksch, Wolfgang; Fateh-Moghadam, Suzanne

    2015-01-01

    Since patients with phenylketonuria (PKU) have to follow a lifelong restriction of natural protein to lower phenylalanine-intake, they never eat fish. This diet may lead to a chronic deficit of omega-3 and omega-6 fatty acids with the risk of early atherosclerotic changes. The aim of the study was to analyse the fatty acid profile of PKU patients and to correlate the results with surrogate markers of early atherosclerotic changes [enhanced carotid intima media thickness (CIMT) and ß-stiffness index] and platelet activation. In 43 PKU patients and in 58 healthy controls we prospectively examined the fatty acid profile, CIMT, ß-stiffness index and platelet activation (flow cytometric determination of markers of platelet activation). CIMT was measured bilaterally by ultrasound. CIMTmean was defined as the mean value of the sum of CIMTleft and CIMTright. Despite of lower HDL-cholesterol and higher triglyceride concentrations in the PKU group, there was no significant difference in the omega-6 or omega-3 fatty acid profile, CIMT, ß-stiffness index between both groups. Platelet activation was not enhanced in the PKU group. Fish-free diet does not induce early atherosclerotic changes or enhanced platelet activation in PKU patients.

  3. Memory-Enhancing Activity of Palmatine in Mice Using Elevated Plus Maze and Morris Water Maze

    Directory of Open Access Journals (Sweden)

    Dinesh Dhingra

    2012-01-01

    Full Text Available The present study was designed to evaluate the effect of palmatine on memory of Swiss young male albino mice. Palmatine (0.1, 0.5, 1 mg/kg, i.p. and physostigmine (0.1 mg/kg, i.p. per se were administered for 10 successive days to separate groups of mice. Effect of drugs on learning and memory of mice was evaluated using elevated plus maze and Morris water maze. Brain acetylcholinesterase activity was also estimated. Effect of palmatine on scopolamine- and diazepam-induced amnesia was also investigated. Palmatine (0.5 and 1 mg/kg and physostigmine significantly improved learning and memory of mice, as indicated by decrease in transfer latency using elevated plus maze, and decrease in escape latency during training and increase in time spent in target quadrant during retrieval using Morris water maze. The drugs did not show any significant effect on locomotor activity of the mice. Memory-enhancing activity of palmatine (1 mg/kg was comparable to physostigmine. Palmatine (1 mg/kg significantly reversed scopolamine- and diazepam-induced amnesia in mice. Palmatine and physostigmine also significantly reduced brain acetylcholinesterase activity of mice. Thus, palmatine showed memory-enhancing activity in mice probably by inhibiting brain acetylcholinesterase activity, through involvement of GABA-benzodiazepine pathway, and due to its antioxidant activity.

  4. N-carbamylglutamate enhances pregnancy outcome in rats through activation of the PI3K/PKB/mTOR signaling pathway.

    Directory of Open Access Journals (Sweden)

    Xiangfang Zeng

    Full Text Available Administration of N-carbamylglutamate (NCG, an analogue of endogenous N-acetyl-glutamate (an activator of arginine synthesis has been shown to enhance neonatal growth by increasing circulating arginine levels. However, the effect of NCG on pregnancy remains unknown. This study examined the effects of NCG on pregnancy outcome and evaluated potential mechanisms involved. Reproductive performance, embryo implantation, and concentration of amino acids in serum and uterine flushing, were determined in rats fed control or NCG supplemented diets. Ishikawa cells and JAR cells were used to examine the mechanism by which NCG affects embryo implantation. Dietary NCG supplementation increased serum levels of arginine, onithine, and proline, as well as uterine levels of arginine, glutamine, glutamate, and proline. Additionally, it stimulated LIF expression, and enhanced the activation of signal transduction and activator of transcription 3 (Stat3, protein kinase B (PKB, and 70-kDa ribosomal protein S6 kinase (S6K1 during the periimplantation period, resulting in an increase in litter size but not birth weight. In uterine Ishikawa cells, LIF expression was also enhanced by treatment with arginine and its metabolites. In trophoblast JAR cells, treatment with arginine and its metabolites enhanced Stat3, PKB, and S6K1 activation and facilitated cellular adhesion activity. These effects were abolished by pretreatment with inhibitors of phosphatidylinositol 3-kinase (wortmannin and mammalian target of rapamycin (rapamycin. The results demonstrate that NCG supplementation enhances pregnancy outcome and have important implications for the pregnancy outcome of mammalian species.

  5. 78 FR 47676 - Agency Information Collection Activities; Comment Request; Credit Enhancement for Charter School...

    Science.gov (United States)

    2013-08-06

    ... the use of information technology. Please note that written comments received in response to this... DEPARTMENT OF EDUCATION [Docket No. ED-2013-ICCD-0101] Agency Information Collection Activities; Comment Request; Credit Enhancement for Charter School Facilities Program Performance Report AGENCY...

  6. Autophagic machinery activated by dengue virus enhances virus replication

    International Nuclear Information System (INIS)

    Lee, Y.-R.; Lei, H.-Y.; Liu, M.-T.; Wang, J.-R.; Chen, S.-H.; Jiang-Shieh, Y.-F.; Lin, Y.-S.; Yeh, T.-M.; Liu, C.-C.; Liu, H.-S.

    2008-01-01

    Autophagy is a cellular response against stresses which include the infection of viruses and bacteria. We unravel that Dengue virus-2 (DV2) can trigger autophagic process in various infected cell lines demonstrated by GFP-LC3 dot formation and increased LC3-II formation. Autophagosome formation was also observed under the transmission electron microscope. DV2-induced autophagy further enhances the titers of extracellular and intracellular viruses indicating that autophagy can promote viral replication in the infected cells. Moreover, our data show that ATG5 protein is required to execute DV2-induced autophagy. All together, we are the first to demonstrate that DV can activate autophagic machinery that is favorable for viral replication

  7. Quantitative analysis of contrast-enhanced ultrasonography of the bowel wall can predict disease activity in inflammatory bowel disease

    Energy Technology Data Exchange (ETDEWEB)

    Romanini, Laura, E-mail: laura.romanini@libero.it [Department of Radiology, Spedali Civili di Brescia, P.le Spedali Civili, 1, 25123 Brescia (Italy); Passamonti, Matteo, E-mail: matteopassamonti@gmail.com [Department of Radiology-AO Provincia di Lodi, Via Fissiraga, 15, 26900 Lodi (Italy); Navarria, Mario, E-mail: navarria.mario@tiscali.it [Department of Radiology-ASL Vallecamonica-Sebino, Via Manzoni 142, 25040 Esine, BS (Italy); Lanzarotto, Francesco, E-mail: francesco.lanzarotto@spedalicivili.brescia.it [Department of Gastroenterology, Spedali Civili di Brescia, P.le Spedali Civili, 1, 25123 Brescia (Italy); Villanacci, Vincenzo, E-mail: villanac@alice.it [Department of Pathology, Spedali Civili di Brescia, P.le Spedali Civili, 1, 25123 Brescia (Italy); Grazioli, Luigi, E-mail: radiologia1@spedalicivili.brescia.it [Department of Radiology, Spedali Civili di Brescia, P.le Spedali Civili, 1, 25123 Brescia (Italy); Calliada, Fabrizio, E-mail: fabrizio.calliada@gmail.com [Department of Radiology, University of Pavia, Viale Camillo Golgi 19, 27100 Pavia (Italy); Maroldi, Roberto, E-mail: rmaroldi@gmail.com [Department of Radiology, University of Brescia, P.le Spedali Civili, 1, 25123 Brescia (Italy)

    2014-08-15

    Purpose: To evaluate the accuracy of quantitative analysis of bowel wall enhancement in inflammatory bowel disease (IBD) with contrast enhanced ultrasound (CEUS) by comparing the results with vascular density in a biopsy sample from the same area of the intestinal tract, and to determine the usefulness of this analysis for the prediction of disease activity. Materials and methods: This prospective study was approved by our institute's ethics committee and all patients gave written informed consent. We enrolled 33 consecutive adult patients undergoing colonoscopy and biopsy for IBD. All patients underwent CEUS and the results were quantitatively analyzed. Vessel count per high-power field on biopsy specimens was compared with colonoscopy, baseline ultrasonography, and CEUS findings, and with analysis of peak intensity, time to peak, regional blood volume, mean transit time, and regional blood flow. Results in patients with high and low vascular density were compared using Fisher's test, t-test, Pearson's correlation test, and receiver operating characteristic curve (ROC) analysis. Cutoff values were determined using ROC analysis, and sensitivity and specificity were calculated. Results: High vascular density (>265 vessels per field) on histological examination was significantly correlated with active disease on colonoscopy, baseline ultrasonography, and CEUS (p < .0001). Quantitative analysis showed a higher enhancement peak, a shorter time to peak enhancement, a higher regional blood flow and regional blood volume in patients with high vascular density than in those with low vascular density. Cutoff values to distinguish between active and inactive disease were identified for peak enhancement (>40.5%), and regional blood flow (>54.8 ml/min). Conclusion: Quantitative analysis of CEUS data correlates with disease activity as determined by vascular density. Quantitative parameters of CEUS can be used to predict active disease with high sensitivity and

  8. Quantitative analysis of contrast-enhanced ultrasonography of the bowel wall can predict disease activity in inflammatory bowel disease

    International Nuclear Information System (INIS)

    Romanini, Laura; Passamonti, Matteo; Navarria, Mario; Lanzarotto, Francesco; Villanacci, Vincenzo; Grazioli, Luigi; Calliada, Fabrizio; Maroldi, Roberto

    2014-01-01

    Purpose: To evaluate the accuracy of quantitative analysis of bowel wall enhancement in inflammatory bowel disease (IBD) with contrast enhanced ultrasound (CEUS) by comparing the results with vascular density in a biopsy sample from the same area of the intestinal tract, and to determine the usefulness of this analysis for the prediction of disease activity. Materials and methods: This prospective study was approved by our institute's ethics committee and all patients gave written informed consent. We enrolled 33 consecutive adult patients undergoing colonoscopy and biopsy for IBD. All patients underwent CEUS and the results were quantitatively analyzed. Vessel count per high-power field on biopsy specimens was compared with colonoscopy, baseline ultrasonography, and CEUS findings, and with analysis of peak intensity, time to peak, regional blood volume, mean transit time, and regional blood flow. Results in patients with high and low vascular density were compared using Fisher's test, t-test, Pearson's correlation test, and receiver operating characteristic curve (ROC) analysis. Cutoff values were determined using ROC analysis, and sensitivity and specificity were calculated. Results: High vascular density (>265 vessels per field) on histological examination was significantly correlated with active disease on colonoscopy, baseline ultrasonography, and CEUS (p < .0001). Quantitative analysis showed a higher enhancement peak, a shorter time to peak enhancement, a higher regional blood flow and regional blood volume in patients with high vascular density than in those with low vascular density. Cutoff values to distinguish between active and inactive disease were identified for peak enhancement (>40.5%), and regional blood flow (>54.8 ml/min). Conclusion: Quantitative analysis of CEUS data correlates with disease activity as determined by vascular density. Quantitative parameters of CEUS can be used to predict active disease with high sensitivity and

  9. Self-efficacy enhancing intervention increases light physical activity in people with chronic obstructive pulmonary disease

    Directory of Open Access Journals (Sweden)

    Larson JL

    2014-10-01

    Full Text Available Janet L Larson,1,2 Margaret K Covey,2 Mary C Kapella,2 Charles G Alex,3,4 Edward McAuley,5 1Division of Acute, Critical and Long-Term Care Programs, School of Nursing, University of Michigan, Ann Arbor, MI, 2Department of Biobehavioral Health Science, College of Nursing, University of Illinois at Chicago, Chicago, IL, 3Division of Pulmonary and Critical Care Medicine, Edward Hines Jr VA Hospital, Hines, IL, 4Advocate Christ Medical Center, Oaklawn, IL, 5Department of Kinesiology and Community Health, College of Applied Health Sciences, University of Illinois Urbana-Champagne, Urbana, IL, USA Background: People with chronic obstructive pulmonary disease lead sedentary lives and could benefit from increasing their physical activity. The purpose of this study was to determine if an exercise-specific self-efficacy enhancing intervention could increase physical activity and functional performance when delivered in the context of 4 months of upper body resistance training with a 12-month follow-up. Methods: In this randomized controlled trial, subjects were assigned to: exercise-specific self-efficacy enhancing intervention with upper body resistance training (SE-UBR, health education with upper body resistance training (ED-UBR, or health education with gentle chair exercises (ED-Chair. Physical activity was measured with an accelerometer and functional performance was measured with the Functional Performance Inventory. Forty-nine people with moderate to severe chronic obstructive pulmonary disease completed 4 months of training and provided valid accelerometry data, and 34 also provided accelerometry data at 12 months of follow-up. The self-efficacy enhancing intervention emphasized meeting physical activity guidelines and increasing moderate-to-vigorous physical activity. Results: Differences were observed in light physical activity (LPA after 4 months of training, time by group interaction effect (P=0.045. The SE-UBR group increased time spent in

  10. Examining factors affecting beginning teachers' transfer of learning of ICT-enhanced learning activities in their teaching practice

    NARCIS (Netherlands)

    Agyei, D.D.; Voogt, J.

    2014-01-01

    This study examined 100 beginning teachers’ transfer of learning when utilising Information Communication Technology-enhanced activity-based learning activities. The beginning teachers had participated in a professional development program that was characterised by ‘learning technology by

  11. Enhancing the water oxidation activity of Ni2P nanocatalysts by iron-doping and electrochemical activation

    International Nuclear Information System (INIS)

    Liu, Guang; He, Dongying; Yao, Rui; Zhao, Yong; Li, Jinping

    2017-01-01

    Highlights: •A sol-gel method for synthesis of Fe-doping Ni 2 P nanocatalysts was present. •Fe-doping Ni 2 P sample exhibited high OER activity after electrochemical activation. •In situ formed Fe-NiOOH layer on activated Fe-Ni 2 P provided more active OER sites. -- Abstract: In this work, we reported a facile and safe route for synthesis of Ni 2 P nanocatalysts by sol-gel method and demonstrated that the oxygen evolution reaction (OER) activity of Ni 2 P nanocatalysts can be dramatically enhanced by iron-doping and electrochemical activation. Compared with the fresh Fe-doped Ni 2 P nanocatalysts, a stable Fe-NiOOH layer was formed on the surface of Fe-doped Ni 2 P nanoparticles by electrochemical activation, thus promoting the charge transfer ability and surface electrochemically active sites generation for the electrochemical activated Fe-doped Ni 2 P nanocatalysts, ultimately accounting for the improvement of water oxidation activity, which was evidenced by cyclic voltammograms (CV), electrochemical impedance spectroscopy (EIS), X-ray photoelectron spectra (XPS) as well as high-resolution transmission electron microscopy (HR-TEM) measurements. For water oxidation reaction in 1 M KOH solution, the electrochemical activated Fe-doped Ni 2 P nanocatalysts can attain 10 mA/cm 2 at an overpotential of 292 mV with Tafel slope of 50 mV/dec, which was also much better than that of individual Ni 2 P, Fe 2 P nanocatalysts as well as commercial RuO 2 electrocatalyst. Moreover, long-term stability performance by chronoamperometric and chronopotentiometric tests for the activated Fe-doped Ni 2 P nanocatalysts exhibited no obvious decline within 56 h. It was demonstrated that modulating the OER catalytic activity for metal phosphide by iron-doping and electrochemical activation may provide new opportunities and avenues to engineer high performance electrocatalysts for water splitting.

  12. Regulation of Pancreatic β Cell Mass by Cross-Interaction between CCAAT Enhancer Binding Protein β Induced by Endoplasmic Reticulum Stress and AMP-Activated Protein Kinase Activity.

    Directory of Open Access Journals (Sweden)

    Tomokazu Matsuda

    Full Text Available During the development of type 2 diabetes, endoplasmic reticulum (ER stress leads to not only insulin resistance but also to pancreatic beta cell failure. Conversely, cell function under various stressed conditions can be restored by reducing ER stress by activating AMP-activated protein kinase (AMPK. However, the details of this mechanism are still obscure. Therefore, the current study aims to elucidate the role of AMPK activity during ER stress-associated pancreatic beta cell failure. MIN6 cells were loaded with 5-amino-1-β-D-ribofuranosyl-imidazole-4-carboxamide (AICAR and metformin to assess the relationship between AMPK activity and CCAAT enhancer binding protein β (C/EBPβ expression levels. The effect of C/EBPβ phosphorylation on expression levels was also investigated. Vildagliptin and metformin were administered to pancreatic beta cell-specific C/EBPβ transgenic mice to investigate the relationship between C/EBPβ expression levels and AMPK activity in the pancreatic islets. When pancreatic beta cells are exposed to ER stress, the accumulation of the transcription factor C/EBPβ lowers the AMP/ATP ratio, thereby decreasing AMPK activity. In an opposite manner, incubation of MIN6 cells with AICAR or metformin activated AMPK, which suppressed C/EBPβ expression. In addition, administration of the dipeptidyl peptidase-4 inhibitor vildagliptin and metformin to pancreatic beta cell-specific C/EBPβ transgenic mice decreased C/EBPβ expression levels and enhanced pancreatic beta cell mass in proportion to the recovery of AMPK activity. Enhanced C/EBPβ expression and decreased AMPK activity act synergistically to induce ER stress-associated pancreatic beta cell failure.

  13. Dramatization at Extracurricular Activities as a Means to Enhance Foreign Language Teaching

    Directory of Open Access Journals (Sweden)

    Marina Valeryevna Kuimova

    2015-02-01

    Full Text Available The main purpose of foreign language teaching is to learn to communicate and overcome the language barrier. The article studies dramatization and its appropriateness in foreign language teaching, provides criteria for choosing a literary work for dramatization. The use of dramatization at extracurricular activities develops communication abilities, creativity; enhances motivation to learn a foreign language and strengthens students’ confidence in a foreign language.

  14. Impairment of GABA transporter GAT-1 terminates cortical recurrent network activity via enhanced phasic inhibition

    Directory of Open Access Journals (Sweden)

    Daniel Simon Razik

    2013-09-01

    Full Text Available In the central nervous system, GABA transporters (GATs very efficiently clear synaptically released GABA from the extracellular space, and thus exert a tight control on GABAergic inhibition. In neocortex, GABAergic inhibition is heavily recruited during recurrent phases of spontaneous action potential activity which alternate with neuronally quiet periods. Therefore, such activity should be quite sensitive to minute alterations of GAT function. Here, we explored the effects of a gradual impairment of GAT-1 and GAT-2/3 on spontaneous recurrent network activity – termed network bursts and silent periods – in organotypic slice cultures of rat neocortex. The GAT-1 specific antagonist NO-711 depressed activity already at nanomolar concentrations (IC50 for depression of spontaneous multiunit firing rate of 42 nM, reaching a level of 80% at 500-1000 nM. By contrast, the GAT-2/3 preferring antagonist SNAP-5114 had weaker and less consistent effects. Several lines of evidence pointed towards an enhancement of phasic GABAergic inhibition as the dominant activity-depressing mechanism: network bursts were drastically shortened, phasic GABAergic currents decayed slower, and neuronal excitability during ongoing activity was diminished. In silent periods, NO-711 had little effect on neuronal excitability or membrane resistance, quite in contrast to the effects of muscimol, a GABA mimetic which activates GABAA receptors tonically. Our results suggest that an enhancement of phasic GABAergic inhibition efficiently curtails cortical recurrent activity and may mediate antiepileptic effects of therapeutically relevant concentrations of GAT-1 antagonists.

  15. Synergistic retention strategy of RGD active targeting and radiofrequency-enhanced permeability for intensified RF & chemotherapy synergistic tumor treatment.

    Science.gov (United States)

    Zhang, Kun; Li, Pei; He, Yaping; Bo, Xiaowan; Li, Xiaolong; Li, Dandan; Chen, Hangrong; Xu, Huixiong

    2016-08-01

    Despite gaining increasing attention, chelation of multiple active targeting ligands greatly increase the formation probability of protein corona, disabling active targeting. To overcome it, a synergistic retention strategy of RGD-mediated active targeting and radiofrequency (RF) electromagnetic field-enhanced permeability has been proposed here. It is validated that such a special synergistic retention strategy can promote more poly lactic-co-glycolic acid (PLGA)-based capsules encapsulating camptothecin (CPT) and solid DL-menthol (DLM) to enter and retain in tumor in vitro and in vivo upon exposure to RF irradiation, receiving an above 8 fold enhancement in HeLa retention. Moreover, the PLGA-based capsules can respond RF field to trigger the entrapped DLM to generate solid-liquid-gas (SLG) tri-phase transformation for enhancing RF ablation and CPT release. Therefore, depending on the enhanced RF ablation and released CPT and the validated synergistic retention effect, the inhibitory outcome for tumor growth has gained an over 10-fold improvement, realizing RF ablation & chemotherapy synergistic treatment against HeLa solid tumor, which indicates a significant promise in clinical RF ablation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Human PrimPol activity is enhanced by RPA.

    Science.gov (United States)

    Martínez-Jiménez, María I; Lahera, Antonio; Blanco, Luis

    2017-04-10

    Human PrimPol is a primase belonging to the AEP superfamily with the unique ability to synthesize DNA primers de novo, and a non-processive DNA polymerase able to bypass certain DNA lesions. PrimPol facilitates both mitochondrial and nuclear replication fork progression either acting as a conventional TLS polymerase, or repriming downstream of blocking lesions. In vivo assays have shown that PrimPol is rapidly recruited to sites of DNA damage by interaction with the human replication protein A (RPA). In agreement with previous findings, we show here that the higher affinity of RPA for ssDNA inhibits PrimPol activities in short ssDNA templates. In contrast, once the amount of ssDNA increases up to a length in which both proteins can simultaneously bind ssDNA, as expected during replicative stress conditions, PrimPol and RPA functionally interact, and their binding capacities are mutually enhanced. When using M13 ssDNA as template, RPA stimulated both the primase and polymerase activities of PrimPol, either alone or in synergy with Polε. These new findings supports the existence of a functional PrimPol/RPA association that allows repriming at the exposed ssDNA regions formed in the leading strand upon replicase stalling.

  17. A p-n heterojunction of CuI/TiO2 with enhanced photoelectrocatalytic activity for methanol electro-oxidation

    International Nuclear Information System (INIS)

    Sun, Mingjuan; Hu, Jiayue; Zhai, Chunyang; Zhu, Mingshan; Pan, Jianguo

    2017-01-01

    Highlights: •A p-n heterojunction of CuI/TiO 2 is constructed. •CuI/TiO 2 is used as the support for depositing Pt nanoparticles. •Enhanced catalytic activity of MOR by using Pt-CuI/TiO 2 under light irradiation. •Improved charger separation contributes to enhanced photoelectrocatalytic activity. -- Abstract: In this paper, a p-n heterojunction including p-type CuI and n-type TiO 2 is first time constructed to be the support for the deposition of Pt. The as-prepared Pt-CuI/TiO 2 modified electrode is studied for the electrocatalytic oxidation of methanol both in dark and under light illumination. Compare to traditional electrocatalytic oxidation, the electrocatalytic activity of Pt-CuI/TiO 2 for methanol oxidation is improved with 4.0 times upon light illumination. Moreover, compare to bare CuI and TiO 2 upon light illumination, the heterostructure of CuI/TiO 2 displays 4.3 and 9.1 times enhanced electrocatalytic activity for methanol oxidation, respectively. The synergistic effects of photocatalysis and electrocatalysis as well as the effective charge transport in the p-n heterojunction of Pt-CuI/TiO 2 contribute such big enhancement. The present studies indicate that the constructing of p-n heterojunction provides more insights in the fields of photoelectrochemical and photo–assisted fuel cell system.

  18. Auto-ubiquitination of Mdm2 Enhances Its Substrate Ubiquitin Ligase Activity*

    Science.gov (United States)

    Ranaweera, Ruchira S.; Yang, Xiaolu

    2013-01-01

    The RING domain E3 ubiquitin ligase Mdm2 is the master regulator of the tumor suppressor p53. It targets p53 for proteasomal degradation, restraining the potent activity of p53 and enabling cell survival and proliferation. Like most E3 ligases, Mdm2 can also ubiquitinate itself. How Mdm2 auto-ubiquitination may influence its substrate ubiquitin ligase activity is undefined. Here we show that auto-ubiquitination of Mdm2 is an activating event. Mdm2 that has been conjugated to polyubiquitin chains, but not to single ubiquitins, exhibits substantially enhanced activity to polyubiquitinate p53. Mechanistically, auto-ubiquitination of Mdm2 facilitates the recruitment of the E2 ubiquitin-conjugating enzyme. This occurs through noncovalent interactions between the ubiquitin chains on Mdm2 and the ubiquitin binding domain on E2s. Mutations that diminish the noncovalent interactions render auto-ubiquitination unable to stimulate Mdm2 substrate E3 activity. These results suggest a model in which polyubiquitin chains on an E3 increase the local concentration of E2 enzymes and permit the processivity of substrate ubiquitination. They also support the notion that autocatalysis may be a prevalent mode for turning on the activity of latent enzymes. PMID:23671280

  19. Overexpression of OLE1 enhances stress tolerance and constitutively activates the MAPK HOG pathway in Saccharomyces cerevisiae.

    Science.gov (United States)

    Nasution, Olviyani; Lee, Young Mi; Kim, Eunjung; Lee, Yeji; Kim, Wankee; Choi, Wonja

    2017-03-01

    OLE1 of Saccharomyces cerevisiae encodes the sole and essential Δ-9 desaturase catalyzing the conversion of saturated to unsaturated fatty acids. Upon ectopic overexpression of OLE1 in S. cerevisiae, significant increases in the membrane oleic acid content were observed. OLE1-overexpressing strains displayed enhanced tolerance to various stresses, better proton efflux, lower membrane permeability, and lessened internal hydrogen peroxide content. The OLE1-mediated enhanced stress tolerance was considerably diminished upon deletion of HOG1, which encodes the mitogen-activated protein kinase (MAPK) Hog1 of the high osmolarity glycerol (HOG) pathway. Furthermore, OLE1 overexpression constitutively activated Hog1, which remained in the cytoplasm. Hog1 activation was accomplished through the MAPK kinase kinase (MAPKKK) Ssk2, but not Ste11 and Ssk22, the other MAPKKKs of the HOG pathway. Despite its cytoplasmic location, activated Hog1 was able to activate the expression of its canonical targets, including CTT1, HSP12, and STL1, and further, the cAMP and stress response elements present in the promoter. OLE1 overexpression neither caused nor relieved endoplasmic reticulum stress. Individually or in combination, the physiological and molecular changes caused by OLE1 overexpression may contribute to enhanced tolerance to various types of stress. Biotechnol. Bioeng. 2017;114: 620-631. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  20. Preparation, characterization and enhanced visible-light photocatalytic activities of BiPO4/BiVO4 composites

    International Nuclear Information System (INIS)

    Wu, Siyuan; Zheng, Hong; Lian, Youwei; Wu, Yiying

    2013-01-01

    Graphical abstract: - Highlights: • BiPO 4 /BiVO 4 composites were successfully prepared by the hydrothermal method. • BiPO 4 /BiVO 4 composites exhibited broad absorption in the visible region. • Visible-light photocatalytic activities of BiPO 4 /BiVO 4 composites were enhanced. • P/V molar ratio and pH value of the reaction affect photocatalytic activity. • The mechanism of enhanced visible-light photocatalytic activities was discussed. - Abstract: BiPO 4 /BiVO 4 composites with different P/V molar ratios were prepared by the hydrothermal method and the effect of pH values of hydrothermal reaction on photocatalytic activity of BiPO 4 /BiVO 4 composite was investigated. The photocatalysts were characterized by X-ray diffraction, field emission scanning electron microscopy, energy-dispersive spectroscopy, X-ray photoelectron spectroscopy and UV–vis diffuse reflectance spectroscopy. The photocatalytic property of BiPO 4 /BiVO 4 was evaluated by photocatalytic degradation of Methylene blue under visible light irradiation. The results showed that the photocatalytic activity of the composites was much higher than that of pure BiPO 4 and BiVO 4 . The rate constant of Methylene blue degradation over BiPO 4 /BiVO 4 (P/V molar ratio of 5:1 and hydrothermal reaction pH value of 1.5) is 1.7 times that of pure BiVO 4 . The photocatalytic activity enhancement of BiPO 4 /BiVO 4 composite is closely related to the BiVO 4 functioning as a sensitizer to adsorb visible light and the heterojunction of BiPO 4 /BiVO 4 acting as an active center for hindering the rapid recombination of electron–hole pairs during the photocatalytic reaction

  1. Nitric oxide facilitates active avoidance learning via enhancement of glutamate levels in the hippocampal dentate gyrus.

    Science.gov (United States)

    Wang, Shi; Pan, De-Xi; Wang, Dan; Wan, Peng; Qiu, De-Lai; Jin, Qing-Hua

    2014-09-01

    The hippocampus is a key structure for learning and memory in mammals, and long-term potentiation (LTP) is an important cellular mechanism responsible for learning and memory. Despite a number of studies indicating that nitric oxide (NO) is involved in the formation and maintenance of LTP as a retrograde messenger, few studies have used neurotransmitter release as a visual indicator in awake animals to explore the role of NO in learning-dependent long-term enhancement of synaptic efficiency. Therefore, in the present study, the effects of l-NMMA (a NO synthase inhibitor) and SNP (a NO donor) on extracellular glutamate (Glu) concentrations and amplitudes of field excitatory postsynaptic potential (fEPSP) were measured in the hippocampal dentate gyrus (DG) region during the acquisition and extinction of active-avoidance behavior in freely-moving conscious rats. In the control group, the extracellular concentration of Glu in the DG was significantly increased during the acquisition of active-avoidance behavior and gradually returned to baseline levels following extinction training. In the experimental group, the change in Glu concentration was significantly reduced by local microinjection of l-NMMA, as was the acquisition of the active-avoidance behavior. In contrast, the change in Glu concentration was significantly enhanced by SNP, and the acquisition of the active-avoidance behavior was significantly accelerated. Furthermore, in all groups, the changes in extracellular Glu were accompanied by corresponding changes in fEPSP amplitude and active-avoidance behavior. Our results suggest that NO in the hippocampal DG facilitates active avoidance learning via enhancements of glutamate levels and synaptic efficiency in rats. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. Enhancement of activated sludge disintegration and dewaterability by Fenton process

    Science.gov (United States)

    Heng, G. C.; Isa, M. H.

    2016-06-01

    Municipal and industrial wastewater treatment plants produce large amounts of sludge. This excess sludge is an inevitable drawback inherent to the activated sludge process. In this study, the waste activated sludge was obtained from the campus wastewater treatment plant at Universiti Teknologi PETRONAS (UTP), Malaysia. Fenton pretreatment was optimized by using the response surface methodology (RSM) to study the effects of three operating conditions including the dosage of H2O2 (g H2O2/kg TS), the molar ratio of H2O2/Fe2+ and reaction time. The optimum operating variables to achieve MLVSS removal 65%, CST reduction 28%, sCOD 11000 mg/L and EPS 500 mg/L were: 1000 g H2O2/kg TS, H2O2/Fe2+ molar ratio 70 and reaction time 45 min. Fenton process was proved to be able to enhance the sludge disintegration and dewaterability.

  3. Enhancement of sludge reduction and methane production by removing extracellular polymeric substances from waste activated sludge.

    Science.gov (United States)

    Nguyen, Minh Tuan; Mohd Yasin, Nazlina Haiza; Miyazaki, Toshiki; Maeda, Toshinari

    2014-12-01

    The management of waste activated sludge (WAS) recycling is a concern that affects the development of the future low-carbon society, particularly sludge reduction and biomass utilization. In this study, we investigated the effect of removing extracellular polymeric substances (EPS), which play important roles in the adhesion and flocculation of WAS, on increased sludge disintegration, thereby enhancing sludge reduction and methane production by anaerobic digestion. EPS removal from WAS by ethylenediaminetetraacetic acid (EDTA) significantly enhanced sludge reduction, i.e., 49 ± 5% compared with 27 ± 1% of the control at the end the digestion process. Methane production was also improved in WAS without EPS by 8881 ± 109 CH4 μmol g(-1) dry-weight of sludge. Microbial activity was determined by denaturing gradient gel electrophoresis and real-time polymerase chain reaction, which showed that the hydrolysis and acetogenesis stages were enhanced by pretreatment with 2% EDTA, with a larger methanogenic community and better methane production. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Enhanced gravity-wave activity and interhemispheric coupling during the MaCWAVE/MIDAS northern summer program 2002

    Directory of Open Access Journals (Sweden)

    E. Becker

    2006-07-01

    Full Text Available We present new sensitivity experiments that link observed anomalies of the mesosphere and lower thermosphere at high latitudes during the MaCWAVE/MIDAS summer program 2002 to enhanced planetary Rossby-wave activity in the austral winter troposphere.

    We employ the same general concept of a GCM having simplified representations of radiative and latent heating as in a previous study by Becker et al. (2004. In the present version, however, the model includes no gravity wave (GW parameterization. Instead we employ a high vertical and a moderate horizontal resolution in order to describe GW effects explicitly. This is supported by advanced, nonlinear momentum diffusion schemes that allow for a self-consistent generation of inertia and mid-frequency GWs in the lower atmosphere, their vertical propagation into the mesosphere and lower thermosphere, and their subsequent dissipation which is induced by prescribed horizontal and vertical mixing lengths as functions of height.

    The main anomalies in northern summer 2002 consist of higher temperatures than usual above 82 km, an anomalous eastward mean zonal wind between 70 and 90 km, an altered meridional flow, enhanced turbulent dissipation below 80 km, and enhanced temperature variations associated with GWs. These signals are all reasonably described by differences between two long-integration perpetual model runs, one with normal July conditions, and another run with modified latent heating in the tropics and Southern Hemisphere to mimic conditions that correspond to the unusual austral winter 2002. The model response to the enhanced winter hemisphere Rossby-wave activity has resulted in both an interhemispheric coupling through a downward shift of the GW-driven branch of the residual circulation and an increased GW activity at high summer latitudes. Thus a quantitative explanation of the dynamical state of the northern mesosphere and lower

  5. Location-Enhanced Activity Recognition in Indoor Environments Using Off the Shelf Smart Watch Technology and BLE Beacons.

    Science.gov (United States)

    Filippoupolitis, Avgoustinos; Oliff, William; Takand, Babak; Loukas, George

    2017-05-27

    Activity recognition in indoor spaces benefits context awareness and improves the efficiency of applications related to personalised health monitoring, building energy management, security and safety. The majority of activity recognition frameworks, however, employ a network of specialised building sensors or a network of body-worn sensors. As this approach suffers with respect to practicality, we propose the use of commercial off-the-shelf devices. In this work, we design and evaluate an activity recognition system composed of a smart watch, which is enhanced with location information coming from Bluetooth Low Energy (BLE) beacons. We evaluate the performance of this approach for a variety of activities performed in an indoor laboratory environment, using four supervised machine learning algorithms. Our experimental results indicate that our location-enhanced activity recognition system is able to reach a classification accuracy ranging from 92% to 100%, while without location information classification accuracy it can drop to as low as 50% in some cases, depending on the window size chosen for data segmentation.

  6. Pain Analysis in Patients with Hepatocellular Carcinoma: Irreversible Electroporation versus Radiofrequency Ablation-Initial Observations

    Energy Technology Data Exchange (ETDEWEB)

    Narayanan, Govindarajan, E-mail: gnarayanan@med.miami.edu; Froud, Tatiana, E-mail: tfroud@med.miami.edu [Miller School of Medicine, University of Miami, Department of Vascular and Interventional Radiology (United States); Lo, Kaming, E-mail: KLo@biostat.med.miami.edu [Miller School of Medicine, University of Miami, Department of Epidemiology and Public Health (United States); Barbery, Katuska J., E-mail: kbarbery@med.miami.edu; Perez-Rojas, Evelyn, E-mail: eprojas@med.miami.edu; Yrizarry, Jose, E-mail: jyrizarr@med.miami.edu [Miller School of Medicine, University of Miami, Department of Vascular and Interventional Radiology (United States)

    2013-02-15

    To retrospectively compare the postprocedure pain of hepatocellular carcinoma treated with irreversible electroporation (IRE) with radiofrequency ablation (RFA). This Health Insurance Portability and Accountability Act-compliant, institutional review board-approved study compared postprocedure pain in 21 patients (15 men, six women; mean age 61.5 years) who underwent IRE of 29 intrahepatic lesions (mean size 2.20 cm) in 28 IRE sessions with 22 patients (16 men, six women; mean age 60.2 years) who underwent RFA of 27 lesions (mean size 3.38 cm) in 25 RFA sessions. Pain was determined by patient-disclosed scores with an 11-point numerical rating scale and 24 h cumulative hydromorphone use from patient-controlled analgesia pump. Complications were noted. Statistical significance was evaluated by Fisher's exact test, the Chi-square test, and Student's t test. There was no significant difference in the cumulative hydromorphone dose (1.54 mg (IRE) vs. 1.24 mg (RFA); P = 0.52) and in the mean pain score (1.96 (IRE) vs. 2.25 (RFA); P = 0.70). In nine (32.14 %) of 28 IRE sessions and 11 (44.0 %) of 25 RFA sessions, patients reported no pain. Complications occurred in three (10.7 %) of 28 IRE treatments and included pneumothorax (n = 1), pleural effusion (n = 1), and bleeding in the form of hemothorax (n = 1); one (4 %) of 25 RFA treatments included burn. IRE is comparable to RFA in the amount of pain that patients experience and the amount of pain medication self-administered. Both modalities were well tolerated by patients. Prospective, randomized trials are necessary to further evaluate these findings.

  7. Pain Analysis in Patients with Hepatocellular Carcinoma: Irreversible Electroporation versus Radiofrequency Ablation—Initial Observations

    International Nuclear Information System (INIS)

    Narayanan, Govindarajan; Froud, Tatiana; Lo, Kaming; Barbery, Katuska J.; Perez-Rojas, Evelyn; Yrizarry, Jose

    2013-01-01

    To retrospectively compare the postprocedure pain of hepatocellular carcinoma treated with irreversible electroporation (IRE) with radiofrequency ablation (RFA). This Health Insurance Portability and Accountability Act–compliant, institutional review board–approved study compared postprocedure pain in 21 patients (15 men, six women; mean age 61.5 years) who underwent IRE of 29 intrahepatic lesions (mean size 2.20 cm) in 28 IRE sessions with 22 patients (16 men, six women; mean age 60.2 years) who underwent RFA of 27 lesions (mean size 3.38 cm) in 25 RFA sessions. Pain was determined by patient-disclosed scores with an 11-point numerical rating scale and 24 h cumulative hydromorphone use from patient-controlled analgesia pump. Complications were noted. Statistical significance was evaluated by Fisher’s exact test, the Chi-square test, and Student’s t test. There was no significant difference in the cumulative hydromorphone dose (1.54 mg (IRE) vs. 1.24 mg (RFA); P = 0.52) and in the mean pain score (1.96 (IRE) vs. 2.25 (RFA); P = 0.70). In nine (32.14 %) of 28 IRE sessions and 11 (44.0 %) of 25 RFA sessions, patients reported no pain. Complications occurred in three (10.7 %) of 28 IRE treatments and included pneumothorax (n = 1), pleural effusion (n = 1), and bleeding in the form of hemothorax (n = 1); one (4 %) of 25 RFA treatments included burn. IRE is comparable to RFA in the amount of pain that patients experience and the amount of pain medication self-administered. Both modalities were well tolerated by patients. Prospective, randomized trials are necessary to further evaluate these findings.

  8. Using Laboratory Activities Enhanced with Concept Cartoons to Support Progression in Students' Understanding of Acid-Base Concepts

    Science.gov (United States)

    Ozmen, Haluk; Demircioglu, Gokhan; Burhan, Yasemin; Naseriazar, Akbar; Demircioglu, Hulya

    2012-01-01

    The aim of this study is to examine the effectiveness of an intervention based on a series of laboratory activities enhanced with concept cartoons. The purpose of the intervention was to enhance students' understanding of acid-base chemistry for eight grade students' from two classes in a Turkish primary school. A pretest-posttest non-equivalent…

  9. NaF-assisted hydrothermal synthesis of Ti-doped hematite nanocubes with enhanced photoelectrochemical activity for water splitting

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Chong; Zhu, Zezhou; Wang, Sibo; Hou, Yidong, E-mail: ydhou@fzu.edu.cn

    2015-12-30

    Graphical abstract: An enhanced photoelectrochemical activity for water splitting was achieved over porous Ti-doped α-Fe{sub 2}O{sub 3} nanocubes. - Highlights: . • Ti-doped hematite nanocubes were successfully prepared by NaF-assisted hydrothermal deposition and subsequent annealing. • Ti-doped α-Fe{sub 2}O{sub 3} nanocubes showed an enhanced PEC activity with an IPCE of 25.2% at 340 nm at 1.23 V vs. RHE. • The enhanced activity of Ti-doped hematite nanocubes can be ascribed to high surface area and fast charge transportation. - Abstract: Ti-doped α-Fe{sub 2}O{sub 3} nanocubes on FTO substrate was prepared by hydrothermal deposition β-FeOOH onto FTO glass with a solution of FeCl{sub 3}, TiOCl{sub 2} and NaF, followed by an appropriate annealing. In comparison to Ti-doped α-Fe{sub 2}O{sub 3} nanorods Ti-doped α-Fe{sub 2}O{sub 3} nanocubes showed an enhanced photoelectrochemical activity for water splitting, with a remarkable IPCE of 25.2% at 340 nm at the potential of 1.23 V vs. RHE. The hematite films were studied in detail by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, UV–vis absorption spectroscopy and electrochemical impedance spectroscopy. On the basis of the obtained results, the improved performance of Ti-doped α-Fe{sub 2}O{sub 3} nanocubes can be ascribed to the porous structure, good electrical conductivity and fast charge transportation of hematite.

  10. Slow electron contribution to inelastic reflection anisotropy

    International Nuclear Information System (INIS)

    Podsvirov, O.A.; Kuznetsov, Yu.A.

    1980-01-01

    Investigated is electron contribution with low energy (up to 1 keV) to the anisotropy of electron inelastic reflection (IRE) from silicon monocrystal (111) within 12-50 keV energy range of primary electrons. Experimental data on IRE anisotropy are presented: delay curves for silicon monocrystal, permitting to separate electrons with the energy up to 1 keV, dependences of IRE anisotropy on the energy of primary electrons for the systems - monocrystalline silicon-amorphous silicon film and delay curves for such systems (film thickness varies from 20 to 2000 A). Suggested is a phenomenologic model, permitting to take into account the contribution of slow electrons to IRE anisotropy: it is supposed, that three groups of electrons take part in the formation of the latter: elastic and inelastic reflected electrons, slow electrons, excited by primary electrons and slow electrons, generated by the reverse flow of the scattered electrons. Contribution of electrons, different by origin, to IRE anisotropy is evaluated in accordance with the experimental data on the basis of this model. It is stated, that slow electrons constitute approximately one half of the IRE anisotropy value, the contribution of both groups of slow electrons being approximately equal

  11. Enhanced antimicrobial activities of silver-nanoparticle-decorated reduced graphene nanocomposites against oral pathogens

    International Nuclear Information System (INIS)

    Peng, Jian-min; Lin, Jia-cheng; Chen, Zhuo-yu; Wei, Meng-chao; Fu, Yuan-xiang; Lu, Shu-shen; Yu, Dong-sheng; Zhao, Wei

    2017-01-01

    As a means of capitalizing on the synergistic properties between reduced graphene nanosheets (R-GNs) and silver nanoparticles (AgNPs), an efficient and convenient chemical reduction method was used to prepare silver-nanoparticle-decorated reduced graphene nanocomposites (R-GNs/Ag). The products were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and Raman spectroscopy, which confirmed the loading of well-dispersed silver nanoparticles on reduced graphene sheets. Their antimicrobial activities against oral pathogens such as Candida albicans, Lactobacillus acidophilus, Streptococcus mutans, and Aggregatibacter actinomycetemcomitans were investigated by MIC determination, the counting of colony-forming units (CFU), agar diffusion tests, and growth curve observation. Compared with pure R-GNs and AgNPs, R-GNs/Ag composites exhibited enhanced antimicrobial properties owing to highly dispersed AgNPs on R-GNs. - Highlights: • This study synthesized R-GNs/Ag composites by a chemical reduction method. • AgNPs were successfully dispersed on reduced graphene nanosheets. • R-GNs/Ag composites showed enhanced antimicrobial activities against oral pathogens compared with plain AgNPs or R-GNs.

  12. Enhanced carotid body chemosensory activity and the cardiovascular alterations induced by intermittent hypoxia

    Directory of Open Access Journals (Sweden)

    Rodrigo eIturriaga

    2014-12-01

    Full Text Available The carotid body (CB plays a main role in the maintenance of the oxygen homeostasis. The hypoxic stimulation of the CB increases the chemosensory discharge, which in turn elicits reflex sympathetic, cardiovascular and ventilatory adjustments. An exacerbate carotid chemosensory activity has been associated with human sympathetic-mediated diseases such as hypertension, insulin resistance, heart failure and obstructive sleep apnea (OSA. Indeed, the CB chemosensory discharge becomes tonically hypereactive in experimental models of OSA and heart failure. Chronic intermittent hypoxia (CIH, a main feature of OSA, enhances CB chemosensory baseline discharges in normoxia and in response to hypoxia, inducing sympathetic overactivity and hypertension. Oxidative stress, increased levels of ET-1, Angiotensin II and pro-inflammatory cytokines, along with a reduced production of NO in the CB, have been associated with the enhanced carotid chemosensory activity. In this review, we will discuss new evidence supporting a main role for the CB chemoreceptor in the autonomic and cardiorespiratory alterations induced by intermittent hypoxia, as well as the molecular mechanisms involved in the CB chemosensory potentiation.

  13. Enhanced carotid body chemosensory activity and the cardiovascular alterations induced by intermittent hypoxia

    Science.gov (United States)

    Iturriaga, Rodrigo; Andrade, David C.; Del Rio, Rodrigo

    2014-01-01

    The carotid body (CB) plays a main role in the maintenance of the oxygen homeostasis. The hypoxic stimulation of the CB increases the chemosensory discharge, which in turn elicits reflex sympathetic, cardiovascular, and ventilatory adjustments. An exacerbate carotid chemosensory activity has been associated with human sympathetic-mediated diseases such as hypertension, insulin resistance, heart failure, and obstructive sleep apnea (OSA). Indeed, the CB chemosensory discharge becomes tonically hypereactive in experimental models of OSA and heart failure. Chronic intermittent hypoxia (CIH), a main feature of OSA, enhances CB chemosensory baseline discharges in normoxia and in response to hypoxia, inducing sympathetic overactivity and hypertension. Oxidative stress, increased levels of ET-1, Angiotensin II and pro-inflammatory cytokines, along with a reduced production of NO in the CB, have been associated with the enhanced carotid chemosensory activity. In this review, we will discuss new evidence supporting a main role for the CB chemoreceptor in the autonomic and cardiorespiratory alterations induced by intermittent hypoxia, as well as the molecular mechanisms involved in the CB chemosensory potentiation. PMID:25520668

  14. Enhanced antimicrobial activities of silver-nanoparticle-decorated reduced graphene nanocomposites against oral pathogens

    Energy Technology Data Exchange (ETDEWEB)

    Peng, Jian-min; Lin, Jia-cheng; Chen, Zhuo-yu; Wei, Meng-chao [Guanghua School of Stomatology, Hospital of Stomatology, Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou 510055 (China); Fu, Yuan-xiang; Lu, Shu-shen [School of Chemistry and Chemical Engineering, Sun Yat-sen University, Guangzhou 510275 (China); Yu, Dong-sheng, E-mail: yudsh@mail.sysu.edu.cn [Guanghua School of Stomatology, Hospital of Stomatology, Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou 510055 (China); Zhao, Wei, E-mail: zhaowei3@mail.sysu.edu.cn [Guanghua School of Stomatology, Hospital of Stomatology, Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou 510055 (China)

    2017-02-01

    As a means of capitalizing on the synergistic properties between reduced graphene nanosheets (R-GNs) and silver nanoparticles (AgNPs), an efficient and convenient chemical reduction method was used to prepare silver-nanoparticle-decorated reduced graphene nanocomposites (R-GNs/Ag). The products were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and Raman spectroscopy, which confirmed the loading of well-dispersed silver nanoparticles on reduced graphene sheets. Their antimicrobial activities against oral pathogens such as Candida albicans, Lactobacillus acidophilus, Streptococcus mutans, and Aggregatibacter actinomycetemcomitans were investigated by MIC determination, the counting of colony-forming units (CFU), agar diffusion tests, and growth curve observation. Compared with pure R-GNs and AgNPs, R-GNs/Ag composites exhibited enhanced antimicrobial properties owing to highly dispersed AgNPs on R-GNs. - Highlights: • This study synthesized R-GNs/Ag composites by a chemical reduction method. • AgNPs were successfully dispersed on reduced graphene nanosheets. • R-GNs/Ag composites showed enhanced antimicrobial activities against oral pathogens compared with plain AgNPs or R-GNs.

  15. Microbial activity in subsurface samples before and during nitrate-enhanced bioremediation

    International Nuclear Information System (INIS)

    Thomas, J.M.; Gordy, V.R.; Bruce, C.L.; Ward, C.H.; Hutchins, S.R.; Sinclair, J.L.

    1995-01-01

    A study was conducted to determine the microbial activity at a site contaminated with JP-4 jet fuel before and during nitrate-enhanced bioremediation. Samples at three depths from six different locations were collected aseptically under anaerobic conditions before and during treatment. Cores were located in or close to the source of contamination, downgradient of the source, or outside the zone of contamination. Parameters for microbial characterization included (1) viable counts of aerobic heterotrophic, JP-4 degrading, and oligotrophic bacteria; (2) the most probable number (MPN) of aerobic and anaerobic protozoa; (3) the MPN of total denitrifiers; and (4) the MPN of denitrifiers in hydrocarbon-amended microcosms. The results indicate that the total number of denitrifiers increased by an order of magnitude during nitrate-enhanced bioremediation in most samples. The number of total heterotrophs and JP-4-degrading microorganisms growing aerobically also increased. In addition, the first anaerobic protozoa associated with hydrocarbon-contaminated subsurface materials were detected

  16. NARINGENIN ENHANCED EFFICIENCY OF GUS ACTIVITY IN Passiflora mollissima (H.B.K. Bailey

    Directory of Open Access Journals (Sweden)

    G.O. Cancino

    2004-06-01

    Full Text Available The flavonoid naringenin has been investigated as a possible vir gene inducer in Agrobacterium-mediated transformation in Passiflora mollissima, P. giberti and Nicotiana tabacum cv. Xanthi. The transformation efficiency percentage of explants showing blue GUS expression and the extent of staining following inoculation with Agrobacterium tumefaciens strains EHA 105 and 1065, carrying gus and nptII genes was enhanced with the supplementation of the co-cultivation medium with naringenin. Supplementation of medium with 100µM (strain EHA 105 and 300 µM (strain 1065 naringenin was most effective at enhancing mean (±s.e.m., n=3 GUS activity in leaf explants (20.3 ± 2.4%, strain EHA; 105; 6.0 ± 0.57%, strain 1065 and nodal segments (16.7 ± 2.4% strain EHA 105; 8.3 ± 0.57% strain 1065 of P. mollissima. In P. giberti and N. tabacum maximum GUS activity was obtained in leaf and root explants with 100µM naringenin for both strains analysed. Additionally, when naringenin was added to Luria Bertani (LB medium, both bacterial growth via optical density and colony forming units were higher when compared to control. This is the first report of the use of naringenin to enhance gene transfer from Agrobacterium to plants. These findings suggest that naringenin can be used as an alternative to acetosyringone for vir gene induction in Agrobacterium. This approach may be especially useful in plants that are generally recalcitrant to Agrobacterium-mediatedtransformation.

  17. Infection of human monocyte-derived dendritic cells by ANDES Hantavirus enhances pro-inflammatory state, the secretion of active MMP-9 and indirectly enhances endothelial permeability

    Directory of Open Access Journals (Sweden)

    Lopez-Lastra Marcelo

    2011-05-01

    Full Text Available Abstract Background Andes virus (ANDV, a rodent-borne Hantavirus, is the major etiological agent of Hantavirus cardiopulmonary syndrome (HCPS in South America, which is mainly characterized by a vascular leakage with high rate of fatal outcomes for infected patients. Currently, neither specific therapy nor vaccines are available against this pathogen. ANDV infects both dendritic and epithelial cells, but in despite that the severity of the disease directly correlates with the viral RNA load, considerable evidence suggests that immune mechanisms rather than direct viral cytopathology are responsible for plasma leakage in HCPS. Here, we assessed the possible effect of soluble factors, induced in viral-activated DCs, on endothelial permeability. Activated immune cells, including DC, secrete gelatinolytic matrix metalloproteases (gMMP-2 and -9 that modulate the vascular permeability for their trafficking. Methods A clinical ANDES isolate was used to infect DC derived from primary PBMC. Maturation and pro-inflammatory phenotypes of ANDES-infected DC were assessed by studying the expression of receptors, cytokines and active gMMP-9, as well as some of their functional status. The ANDES-infected DC supernatants were assessed for their capacity to enhance a monolayer endothelial permeability using primary human vascular endothelial cells (HUVEC. Results Here, we show that in vitro primary DCs infected by a clinical isolate of ANDV shed virus RNA and proteins, suggesting a competent viral replication in these cells. Moreover, this infection induces an enhanced expression of soluble pro-inflammatory factors, including TNF-α and the active gMMP-9, as well as a decreased expression of anti-inflammatory cytokines, such as IL-10 and TGF-β. These viral activated cells are less sensitive to apoptosis. Moreover, supernatants from ANDV-infected DCs were able to indirectly enhance the permeability of a monolayer of primary HUVEC. Conclusions Primary human DCs

  18. Pim kinases are upregulated during Epstein-Barr virus infection and enhance EBNA2 activity

    International Nuclear Information System (INIS)

    Rainio, Eeva-Marja; Ahlfors, Helena; Carter, Kara L.; Ruuska, Marja; Matikainen, Sampsa; Kieff, Elliott; Koskinen, Paeivi J.

    2005-01-01

    Latent Epstein-Barr virus (EBV) infection is strongly associated with B-cell proliferative diseases such as Burkitt's lymphoma. Here we show that the oncogenic serine/threonine kinases Pim-1 and Pim-2 enhance the activity of the viral transcriptional activator EBNA2. During EBV infection of primary B-lymphocytes, the mRNA expression levels of pim genes, especially of pim-2, are upregulated and remain elevated in latently infected B-cell lines. Thus, EBV-induced upregulation of Pim kinases and Pim-stimulated EBNA2 transcriptional activity may contribute to the ability of EBV to immortalize B-cells and predispose them to malignant growth

  19. Street football is a feasible health-enhancing activity for homeless men

    DEFF Research Database (Denmark)

    Helge, Eva Wulff; Randers, Morten Bredsgaard; Hornstrup, Therese

    2014-01-01

    This case-control study investigated the feasibility of street football as a health-enhancing activity for homeless men, specifically the musculoskeletal effects of 12 weeks of training. Twenty-two homeless men participated in the football group (FG) and 10 served as controls (C). Plasma.......095 to 0.969 ± 0.090 g/cm(2) (P = 0.02). No effects were observed in C. In conclusion, street football appears to be a feasible training activity with musculoskeletal health benefits for homeless men. The attendance rate and the training intensity were high, and 12 weeks of training resulted...... in a substantial anabolic response in bone metabolism. Postural balance improved markedly, and the overall risk of falling, and hospitalization due to sudden trauma, could be reduced by street football for homeless men....

  20. Understanding how environmental enhancement and conservation activities may benefit health and wellbeing: a systematic review.

    Science.gov (United States)

    Lovell, Rebecca; Husk, Kerryn; Cooper, Chris; Stahl-Timmins, Will; Garside, Ruth

    2015-09-07

    Action taken to enhance or conserve outdoor environments may benefit health and wellbeing through the process of participation but also through improving the environment. There is interest, amongst both health and environmental organisations, in using such activities as health promotion interventions. The objective of this systematic review was to investigate the health and wellbeing impacts of participation in environmental enhancement and conservation activities and to understand how these activities may be beneficial, to whom and in what circumstances or contexts. A theory-led mixed-method systematic review was used to assess evidence of effect and to identify pathways to change (protocol: http://onlinelibrary.wiley.com/doi/ 10.1002/14651858.CD010351/full ). Due to the multi-disciplinary, dispersed and disparate body of evidence an extensive multi-stage search strategy was devised and undertaken. Twenty-seven databases and multiple sources of grey literature were searched and over 200 relevant organisations were contacted. The heterogenous evidence was synthesised using a narrative approach and a conceptual model was developed to illustrate the mechanisms of effect. Due to the limited nature of the evidence additional higher order evidence was sought to assess the plausibility of the proposed mechanisms of effect through which health and wellbeing may accrue. The majority of the quantitative evidence (13 studies; all poor quality and lower-order study designs) was inconclusive, though a small number of positive and negative associations were observed. The qualitative evidence (13 studies; 10 poor quality, 3 good) indicated that the activities were perceived to have value to health and wellbeing through a number of key mechanisms; including exposure to natural environments, achievement, enjoyment and social contact. Additional high level evidence indicated that these pathways were plausible. Despite interest in the use of environmental enhancement activities as a

  1. Proximity does not contribute to activity enhancement in the glucose oxidase-horseradish peroxidase cascade

    Science.gov (United States)

    Zhang, Yifei; Tsitkov, Stanislav; Hess, Henry

    2016-12-01

    A proximity effect has been invoked to explain the enhanced activity of enzyme cascades on DNA scaffolds. Using the cascade reaction carried out by glucose oxidase and horseradish peroxidase as a model system, here we study the kinetics of the cascade reaction when the enzymes are free in solution, when they are conjugated to each other and when a competing enzyme is present. No proximity effect is found, which is in agreement with models predicting that the rapidly diffusing hydrogen peroxide intermediate is well mixed. We suggest that the reason for the activity enhancement of enzymes localized by DNA scaffolds is that the pH near the surface of the negatively charged DNA nanostructures is lower than that in the bulk solution, creating a more optimal pH environment for the anchored enzymes. Our findings challenge the notion of a proximity effect and provide new insights into the role of DNA scaffolds.

  2. Multivalent Porous Silicon Nanoparticles Enhance the Immune Activation Potency of Agonistic CD40 Antibody

    Science.gov (United States)

    Gu, Luo; Ruff, Laura E.; Qin, Zhengtao; Corr, Maripat P.; Hedrick, Stephen M.; Sailor, Michael J.

    2012-01-01

    One of the fundamental paradigms in the use of nanoparticles to treat disease is to evade or suppress the immune system in order to minimize systemic side effects and deliver sufficient nanoparticle quantities to the intended tissues. However, the immune system is the body's most important and effective defense against diseases. It protects the host by identifying and eliminating foreign pathogens as well as selfmalignancies. Here we report a nanoparticle engineered to work with the immune system, enhancing the intended activation of antigen presenting cells (APCs). We show that luminescent porous silicon nanoparticles (LPSiNPs), each containing multiple copies of an agonistic antibody (FGK45) to the APC receptor CD40, greatly enhance activation of B cells. The cellular response to the nanoparticle-based stimulators is equivalent to a 30–40 fold larger concentration of free FGK45. The intrinsic near-infrared photoluminescence of LPSiNPs is used to monitor degradation and track the nanoparticles inside APCs. PMID:22689074

  3. Enhanced high-solids anaerobic digestion of waste activated sludge by the addition of scrap iron.

    Science.gov (United States)

    Zhang, Yaobin; Feng, Yinghong; Yu, Qilin; Xu, Zibin; Quan, Xie

    2014-05-01

    Anaerobic digestion of waste activated sludge usually requires pretreatment procedure to improve the bioavailability of sludge, which involves considerable energy and high expenditures. This study proposes a cost-effective method for enhanced anaerobic digestion of sludge without a pretreatment by directly adding iron into the digester. The results showed that addition of Fe(0) powder could enhance 14.46% methane yield, and Fe scrap (clean scrap) could further enhance methane yield (improving rate 21.28%) because the scrap has better mass transfer efficiency with sludge and liquid than Fe(0) powder. The scrap of Fe with rust (rusty scrap) could induce microbial Fe(III) reduction, which resulted in achieving the highest methane yield (improving rate 29.51%), and the reduction rate of volatile suspended solids (VSS) was also highest (48.27%) among Fe powder, clean scrap and rusty scrap. PCR-DGGE proved that the addition of rusty scrap could enhance diversity of acetobacteria and enrich iron-reducing bacteria to enhance degradation of complex substrates. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Surface-enhanced Raman scattering active gold nanoparticle/nanohole arrays fabricated through electron beam lithography

    Science.gov (United States)

    Wu, Tsunghsueh; Lin, Yang-Wei

    2018-03-01

    Effective surface-enhanced Raman scattering (SERS)-active substrates from gold nanoparticle and gold nanohole arrays were successfully fabricated through electron beam lithography with precise computer-aided control of the unit size and intergap distance. Their SERS performance was evaluated using 4-mercaptobenzoic acid (4-MBA). These gold arrays yielded strong SERS signals under 785 nm laser excitation. The enhancement factors for 4-MBA molecules on the prepared gold nanoparticle and nanohole arrays maxed at 1.08 × 107 and 8.61 × 106, respectively. The observed increase in SERS enhancement was attributed to the localized surface plasmon resonance (LSPR) wavelength shifting toward the near-infrared regime when the gold nanohole diameter increased, in agreement with the theoretical prediction in this study. The contribution of LSPR to the Raman enhancement from nanohole arrays deposited on fluorine-doped tin oxide glass was elucidated by comparing SERS and transmission spectra. This simple fabrication procedure, which entails employing electron beam lithography and the controllability of the intergap distance, suggests highly promising uses of nanohole arrays as functional components in sensing and photonic devices.

  5. Effectiveness and student perceptions of an active learning activity using a headline news story to enhance in-class learning of cell cycle regulation.

    Science.gov (United States)

    Dirks-Naylor, Amie J

    2016-06-01

    An active learning activity was used to engage students and enhance in-class learning of cell cycle regulation in a PharmD level integrated biological sciences course. The aim of the present study was to determine the effectiveness and perception of the in-class activity. After completion of a lecture on the topic of cell cycle regulation, students completed a 10-question multiple-choice quiz before and after engaging in the activity. The activity involved reading of a headline news article published by ScienceDaily.com entitled "One Gene Lost Equals One limb Regained." The name of the gene was deleted from the article and, thus, the end goal of the activity was to determine the gene of interest by the description in the story. The activity included compiling a list of all potential gene candidates before sufficient information was given to identify the gene of interest (p21). A survey was completed to determine student perceptions of the activity. Quiz scores improved by an average of 20% after the activity (40.1 ± 1.95 vs. 59.9 ± 2.14,Pactivity, found the news article interesting, and believed that the activity improved their understanding of cell cycle regulation. The majority of students agreed that the in-class activity piqued their interest for learning the subject matter and also agreed that if they understand a concept during class, they are more likely to want to study that concept outside of class. In conclusion, the activity improved in-class understanding and enhanced interest in cell cycle regulation. Copyright © 2016 The American Physiological Society.

  6. Sports activities enhance the prevalence of rhinitis symptoms in schoolchildren.

    Science.gov (United States)

    Kusunoki, Takashi; Takeuchi, Jiro; Morimoto, Takeshi; Sakuma, Mio; Mukaida, Kumiko; Yasumi, Takahiro; Nishikomori, Ryuta; Heike, Toshio

    2016-03-01

    To evaluate the association between sports activities and allergic symptoms, especially rhinitis, among schoolchildren. This longitudinal survey of schoolchildren collected data from questionnaires regarding allergic symptoms based on the International Study of Asthma and Allergies in Childhood (ISAAC) program and sports participation that were distributed to the parents of children at all 12 public primary schools in Ohmi-Hachiman City, Shiga Prefecture, Japan. Data were collected annually from 2011 until 2014, when the children reached 10 years of age. Blood samples were obtained in 2014, and the levels of immunoglobulin (Ig)E specific to four inhalant allergens were measured. Data from 558 children were analyzed. At 10 years of age, prevalence of asthma and eczema did not differ significantly, while rhinitis was significantly higher (p = 0.009) among children who participated in sports. Prevalence of rhinitis increased as the frequency or duration of sports participation increased (p sports (p = 0.03). Among those who participated in continuous sports activities, the prevalence of rhinitis was significantly higher with prolonged eczema (p = 0.006). Sports activities did not increase sensitization to inhalant allergens. Sports activities enhance the prevalence of rhinitis in schoolchildren. Prolonged eczema, together with sports participation, further promotes the symptoms. The mechanisms of these novel findings warrant further investigation. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  7. Identification of milk proteins enhancing the antimicrobial activity of lactoferrin and lactoferricin.

    Science.gov (United States)

    Murata, M; Wakabayashi, H; Yamauchi, K; Abe, F

    2013-08-01

    Lactoferrin (LF) is known as an iron-binding antimicrobial protein present in exocrine secretions such as milk and releases the potent antimicrobial peptide lactoferricin (LFcin) by hydrolysis with pepsin. The antimicrobial activity of LF and LFcin has been studied well; however, their cooperative action with other milk proteins remains to be elucidated. In this study, we identified milk proteins enhancing the antimicrobial activity of bovine LF and LFcin against gram-negative bacteria, gram-positive bacteria, and fungi. As the target fraction, we isolated a minor milk protein fraction around 15 kDa, which was identified as bovine RNase 5 (angiogenin-1), RNase 4, and angiogenin-2 by matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry. As these proteins are collectively known as the RNase A family, we referred to the target protein fraction as milk RNase of 15 kDa (MR15). The number of colony-forming units of Escherichia coli and other pathogenic microorganisms with the addition of MR15 to LF (MR15:LF ratio=16:1,000) was dramatically lowered than that with LF alone. On the other hand, MR15 itself did not show any reductions in the number of colony-forming units at the concentrations tested. Similarly, the antimicrobial activities of LFcin against various microorganisms were significantly enhanced by the addition of MR15. These results suggest that LF and MR15 may be concomitantly acting antimicrobial agents in milk. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  8. Enhancement of the fibrinolytic activity in plasma by oral administration of nattokinase.

    Science.gov (United States)

    Sumi, H; Hamada, H; Nakanishi, K; Hiratani, H

    1990-01-01

    The existence of a potent fibrinolytic enzyme (nattokinase, NK) in the traditional fermented food called 'natto', was reported by us previously. It was confirmed that oral administration of NK (or natto) produced a mild and frequent enhancement of the fibrinolytic activity in the plasma, as indicated by the fibrinolytic parameters, and the production of tissue plasminogen activator. NK capsules were also administered orally to dogs with experimentally induced thrombosis, and lysis of the thrombi was observed by angiography. The results obtained suggest that NK represents a possible drug for use not only in the treatment of embolism but also in the prevention of the disease, since NK has a proven safety and can be massproduced.

  9. Pretreatment of Parsley (Petroselinum crispum L.) Suspension Cultures with Methyl Jasmonate Enhances Elicitation of Activated Oxygen Species.

    Science.gov (United States)

    Kauss, H.; Jeblick, W.; Ziegler, J.; Krabler, W.

    1994-01-01

    Suspension-cultured cells of parsley (Petroselinum crispum L.) were used to demonstrate an influence of jasmonic acid methyl ester (JAME) on the elicitation of activated oxygen species. Preincubation of the cell cultures for 1 d with JAME greatly enhanced the subsequent induction by an elicitor preparation from cell walls of Phytophtora megasperma f. sp. glycinea (Pmg elicitor) and by the polycation chitosan. Shorter preincubation times with JAME were less efficient, and the effect was saturated at about 5 [mu]M JAME. Treatment of the crude Pmg elicitor with trypsin abolished induction of activated oxygen species, an effect similar to that seen with elicitation of coumarin secretion. These results suggest that JAME conditioned the parsley suspension cells in a time-dependent manner to become more responsive to elicitation, reminiscent of developmental effects caused by JAME in whole plants. It is interesting that pretreatment of the parsley cultures with 2,6-dichloroisonicotinic and 5-chlorosalicylic acid only slightly enhanced the elicitation of activated oxygen species, whereas these substances greatly enhanced the elicitation of coumarin secretion. Therefore, these presumed inducers of systemic acquired resistance exhibit a specificity different from JAME. PMID:12232189

  10. A supermolecular curcumin for enhanced antiproliferative and proapoptotic activities: molecular characteristics, computer modeling and in vivo pharmacokinetics

    International Nuclear Information System (INIS)

    Tan Qunyou; Wu Jianyong; Li Yi; Zhang Jingqing; Mei Hu; Zhao Chunjing

    2013-01-01

    The supermolecular curcumin (SMCCM) exhibiting remarkably improved solubility and release characteristics was fabricated to increase the oral bioavailability in rat as well as the antiproliferative and proapoptotic activities of curcumin (CCM) against human lung adenocarcinoma cell A549. SMCCM was characterized by differential scanning calorimetry, Fourier transform infrared spectroscopy, morphology and structure, aqueous solubility, and release behavior in vitro. Computer modeling of the supermolecular structure was performed. The pharmacokinetics, antiproliferative and proapoptotic activities of SMCCM were evaluated. The mechanisms by which SMCCM inhibited proliferation and induced apoptosis were identified. The formation of SMCCM was testified and the supermolecular structure was studied by a computer modeling technique. Compared to free CCM, SMCCM with much higher aqueous solubility exhibited obviously enhanced release and more favorable pharmacokinetic profiles, and, furthermore, SMCCM showed higher anticancer efficacy, enhanced induction of G2/M-phase arrest and apoptosis in A549 cells, which might be involved with the increases in reactive oxygen species production and intracellular Ca 2+ accumulation, and a decrease in mitochondrial membrane potential. SMCCM remarkably enhanced not only the oral bioavailability but also the antiproliferative and proapoptotic activities of CCM along with improved solubility and release characteristics of CCM. (paper)

  11. A supermolecular curcumin for enhanced antiproliferative and proapoptotic activities: molecular characteristics, computer modeling and in vivo pharmacokinetics

    Science.gov (United States)

    Tan, Qunyou; Wu, Jianyong; Li, Yi; Mei, Hu; Zhao, Chunjing; Zhang, Jingqing

    2013-01-01

    The supermolecular curcumin (SMCCM) exhibiting remarkably improved solubility and release characteristics was fabricated to increase the oral bioavailability in rat as well as the antiproliferative and proapoptotic activities of curcumin (CCM) against human lung adenocarcinoma cell A549. SMCCM was characterized by differential scanning calorimetry, Fourier transform infrared spectroscopy, morphology and structure, aqueous solubility, and release behavior in vitro. Computer modeling of the supermolecular structure was performed. The pharmacokinetics, antiproliferative and proapoptotic activities of SMCCM were evaluated. The mechanisms by which SMCCM inhibited proliferation and induced apoptosis were identified. The formation of SMCCM was testified and the supermolecular structure was studied by a computer modeling technique. Compared to free CCM, SMCCM with much higher aqueous solubility exhibited obviously enhanced release and more favorable pharmacokinetic profiles, and, furthermore, SMCCM showed higher anticancer efficacy, enhanced induction of G2/M-phase arrest and apoptosis in A549 cells, which might be involved with the increases in reactive oxygen species production and intracellular Ca2+ accumulation, and a decrease in mitochondrial membrane potential. SMCCM remarkably enhanced not only the oral bioavailability but also the antiproliferative and proapoptotic activities of CCM along with improved solubility and release characteristics of CCM.

  12. Enhanced photoelectrochemical and photocatalytic activity in visible-light-driven Ag/BiVO_4 inverse opals

    International Nuclear Information System (INIS)

    Fang, Liang; Nan, Feng; Yang, Ying; Cao, Dawei

    2016-01-01

    BiVO_4 photonic crystal inverse opals (io-BiVO_4) with highly dispersed Ag nanoparticles (NPs) were prepared by the nanosphere lithography method combining the pulsed current deposition method. The incorporation of the Ag NPs can significantly improve the photoelectrochemical and photocatalytic activity of BiVO_4 inverse opals in the visible light region. The photocurrent density of the Ag/io-BiVO_4 sample is 4.7 times higher than that of the disordered sample without the Ag NPs, while the enhancement factor of the corresponding kinetic constant in photocatalytic experiment is approximately 3. The improved photoelectrochemical and photocatalytic activity is benefited from two reasons: one is the enhanced light harvesting owing to the coupling between the slow light and localized surface plasmon resonance effect; the other is the efficient separation of charge carriers due to the Schottky barriers.

  13. The Start2Bike program is effective in increasing health-enhancing physical activity: a controlled study.

    Science.gov (United States)

    Ooms, Linda; Veenhof, Cindy; de Bakker, Dinny H

    2017-06-29

    The sports club is seen as a new relevant setting to promote health-enhancing physical activity (HEPA) among inactive population groups. Little is known about the effectiveness of strategies and activities implemented in the sports club setting on increasing HEPA levels. This study investigated the effects of Start2Bike, a six-week training program for inactive adults and adult novice cyclers, on HEPA levels of participants in the Netherlands. To measure physical activity, the Short QUestionnaire to ASsess Health-enhancing physical activity was used (SQUASH). Start2Bike participants were measured at baseline, six weeks and six months. A matched control group was measured at baseline and six months. The main outcome measure was whether participants met the Dutch Norm for Health-enhancing Physical Activity (DNHPA: 30 min of moderate-intensity activity on five days a week); Fit-norm (20 min of vigorous-intensity activity on three days a week); and Combi-norm (meeting the DNHPA and/or Fit-norm). Other outcome measures included: total minutes of physical activity per week; and minutes of physical activity per week per domain and intensity category. Statistical analyses consisted of McNemar tests and paired t-tests (within-group changes); and multiple logistic and linear regression analyses (between-group changes). In the Start2Bike group, compliance with Dutch physical activity norms increased significantly, both after six weeks and six months. Control group members did not alter their physical activity behavior. Between-group analyses showed that participants in the Start2Bike group were more likely to meet the Fit-norm at the six-month measurement compared to the control group (odds ratio = 2.5; 95% confidence interval (CI) = 1.1-5.8, p = 0.03). This was due to the Start2Bike participants spending on average 193 min/week more in vigorous-intensity activities (b = 193; 95% CI = 94-293, p Bike positively influences HEPA levels of participants by increasing

  14. The kinesin spindle protein inhibitor filanesib enhances the activity of pomalidomide and dexamethasone in multiple myeloma

    OpenAIRE

    Hernández-García, Susana; San-Segundo, Laura; González-Méndez, Lorena; Corchete, Luis A; Misiewicz-Krzeminska, Irena; Martín-Sánchez, Montserrat; López-Iglesias, Ana-Alicia; Algarín, Esperanza Macarena; Mogollón, Pedro; Díaz-Tejedor, Andrea; Paíno, Teresa; Tunquist, Brian; Mateos, María-Victoria; Gutiérrez, Norma C; Díaz-Rodriguez, Elena

    2017-01-01

    [EN]Kinesin spindle protein inhibition is known to be an effective therapeutic approach in several malignancies. Filanesib (ARRY-520), an inhibitor of this protein, has demonstrated activity in heavily pre-treated multiple myeloma patients. The aim of the work herein was to investigate the activity of filanesib in combination with pomalidomide plus dexamethasone backbone, and the mechanisms underlying the potential synergistic effect. The ability of filanesib to enhance the activity of pomali...

  15. Silver nanoparticles anchored reduced graphene oxide for enhanced electrocatalytic activity towards methanol oxidation

    Science.gov (United States)

    Kumar, Sanjeev; Mahajan, Mani; Singh, Rajinder; Mahajan, Aman

    2018-02-01

    In this report, silver nanoparticles (Ag NPs) anchored reduced graphene oxide (rGO) sheets (rGO/Ag) nanohybrid has been explored as anode material in direct methanol fuel cells (DMFCs). The synthesized rGO/Ag nanohybrid is characterized by XRD, XPS, FTIR spectroscopy and HRTEM techniques. Cyclic voltammograms demonstrate that the rGO/Ag nanohybrid exhibits higher electrocatalytic activity in comparison to rGO sheets for methanol oxidation reaction (MOR). This enhancement is attributed to the synergetic effect produced by the presence of more active sites provided by Ag NPs anchored on a conducting network of large surface area rGO sheets.

  16. Synthesis of hierarchical anatase TiO 2 nanostructures with tunable morphology and enhanced photocatalytic activity

    KAUST Repository

    Rahal, Raed; Wankhade, Atul V.; Cha, Dong Kyu; Fihri, Aziz; Ould-Chikh, Samy; Patil, Umesh; Polshettiwar, Vivek

    2012-01-01

    A facile one-pot method to prepare three-dimensional hierarchical nanostructures of titania with good control over their morphologies without the use of hydrofluoric acid is developed. The reaction is performed under microwave irradiation conditions in pure water, and enables enhanced photocatalytic activity. This study indicates that photocatalytic activity depends not only on the surface area but also on the morphology of the titania. © 2012 The Royal Society of Chemistry.

  17. Cytokinin oxidase from Phaseolus vulgaris callus tissues. Enhanced in vitro activity of the enzyme in the presence of copper-imidazole complexes

    International Nuclear Information System (INIS)

    Chatfield, J.M.; Armstrong, D.J.

    1987-01-01

    The effects of metal ions on cytokinin oxidase activity extracted from callus tissues of Phaseolus vulgaris L. cv Great Northern have been examined using an assay based on the oxidation of N 6 -(Δ 2 -isopentenyl)-adenine-2,8- 3 H (i 6 Ade) to adenine (Ade). The addition of cupric ions to reaction mixtures containing imidazole buffer markedly enhanced cytokinin oxidase activity. In the presence of optimal concentrations of copper and imidazole, cytokinin oxidase activity was stimulated more than 20-fold. The effect was enzyme dependent, specific for copper, and observed only in the presence of imidazole. The substrate specificity of the copper-imidazole enhanced reaction, as judged by substrate competition tests, was the same as that observed in the absence of copper and imidazole. Similarly, in tests involving DEAE-cellulose chromatography, elution profiles of cytokinin oxidase activity determined using a copper-imidazole enhanced assay were identical to those obtained using an assay without copper and imidazole. On the basis of these results, the addition of copper and imidazole to reaction mixtures used to assay for cytokinin oxidase activity is judged to provide a reliable and specific assay of greatly enhanced sensitivity for the enzyme. The mechanism by which copper and imidazole enhance cytokinin oxidase activity is not certain, but the reaction catalyzed by the enzyme was not inhibited by anaerobic conditions when these reagents were present. This observation suggests that copper-imidazole complexes are substituting for oxygen in the reaction mechanism by which cytokinin oxidase effects cleavage of the N 6 -side chain of i 6 Ade

  18. Palladium nanoparticles encapsulated in core-shell silica: A structured hydrogenation catalyst with enhanced activity for reduction of oxyanion water pollutants

    KAUST Repository

    Wang, Yin; Liu, Jinyong; Wang, Peng; Werth, Charles; Strathmann, Timothy J.

    2014-01-01

    Noble metal nanoparticles have been applied to mediate catalytic removal of toxic oxyanions and halogenated hydrocarbons in contaminated water using H2 as a clean and sustainable reductant. However, activity loss by nanoparticle aggregation and difficulty of nanoparticle recovery are two major challenges to widespread technology adoption. Herein, we report the synthesis of a core-shell-structured catalyst with encapsulated Pd nanoparticles and its enhanced catalytic activity in reduction of bromate (BrO3-), a regulated carcinogenic oxyanion produced during drinking water disinfection process, using 1 atm H2 at room temperature. The catalyst material consists of a nonporous silica core decorated with preformed octahedral Pd nanoparticles that were further encapsulated within an ordered mesoporous silica shell (i.e., SiO2@Pd@mSiO2). Well-defined mesopores (2.3 nm) provide a physical barrier to prevent Pd nanoparticle (6 nm) movement, aggregation, and detachment from the support into water. Compared to freely suspended Pd nanoparticles and SiO2@Pd, encapsulation in the mesoporous silica shell significantly enhanced Pd catalytic activity (by a factor of 10) under circumneutral pH conditions that are most relevant to water purification applications. Mechanistic investigation of material surface properties combined with Langmuir-Hinshelwood modeling of kinetic data suggest that mesoporous silica shell enhances activity by promoting BrO3- adsorption near the Pd active sites. The dual function of the mesoporous shell, enhancing Pd catalyst activity and preventing aggregation of active nanoparticles, suggests a promising general strategy of using metal nanoparticle catalysts for water purification and related aqueous-phase applications.

  19. Palladium nanoparticles encapsulated in core-shell silica: A structured hydrogenation catalyst with enhanced activity for reduction of oxyanion water pollutants

    KAUST Repository

    Wang, Yin

    2014-10-03

    Noble metal nanoparticles have been applied to mediate catalytic removal of toxic oxyanions and halogenated hydrocarbons in contaminated water using H2 as a clean and sustainable reductant. However, activity loss by nanoparticle aggregation and difficulty of nanoparticle recovery are two major challenges to widespread technology adoption. Herein, we report the synthesis of a core-shell-structured catalyst with encapsulated Pd nanoparticles and its enhanced catalytic activity in reduction of bromate (BrO3-), a regulated carcinogenic oxyanion produced during drinking water disinfection process, using 1 atm H2 at room temperature. The catalyst material consists of a nonporous silica core decorated with preformed octahedral Pd nanoparticles that were further encapsulated within an ordered mesoporous silica shell (i.e., SiO2@Pd@mSiO2). Well-defined mesopores (2.3 nm) provide a physical barrier to prevent Pd nanoparticle (6 nm) movement, aggregation, and detachment from the support into water. Compared to freely suspended Pd nanoparticles and SiO2@Pd, encapsulation in the mesoporous silica shell significantly enhanced Pd catalytic activity (by a factor of 10) under circumneutral pH conditions that are most relevant to water purification applications. Mechanistic investigation of material surface properties combined with Langmuir-Hinshelwood modeling of kinetic data suggest that mesoporous silica shell enhances activity by promoting BrO3- adsorption near the Pd active sites. The dual function of the mesoporous shell, enhancing Pd catalyst activity and preventing aggregation of active nanoparticles, suggests a promising general strategy of using metal nanoparticle catalysts for water purification and related aqueous-phase applications.

  20. Activating RNAs associate with Mediator to enhance chromatin architecture and transcription.

    Science.gov (United States)

    Lai, Fan; Orom, Ulf A; Cesaroni, Matteo; Beringer, Malte; Taatjes, Dylan J; Blobel, Gerd A; Shiekhattar, Ramin

    2013-02-28

    Recent advances in genomic research have revealed the existence of a large number of transcripts devoid of protein-coding potential in multiple organisms. Although the functional role for long non-coding RNAs (lncRNAs) has been best defined in epigenetic phenomena such as X-chromosome inactivation and imprinting, different classes of lncRNAs may have varied biological functions. We and others have identified a class of lncRNAs, termed ncRNA-activating (ncRNA-a), that function to activate their neighbouring genes using a cis-mediated mechanism. To define the precise mode by which such enhancer-like RNAs function, we depleted factors with known roles in transcriptional activation and assessed their role in RNA-dependent activation. Here we report that depletion of the components of the co-activator complex, Mediator, specifically and potently diminished the ncRNA-induced activation of transcription in a heterologous reporter assay using human HEK293 cells. In vivo, Mediator is recruited to ncRNA-a target genes and regulates their expression. We show that ncRNA-a interact with Mediator to regulate its chromatin localization and kinase activity towards histone H3 serine 10. The Mediator complex harbouring disease- displays diminished ability to associate with activating ncRNAs. Chromosome conformation capture confirmed the presence of DNA looping between the ncRNA-a loci and its targets. Importantly, depletion of Mediator subunits or ncRNA-a reduced the chromatin looping between the two loci. Our results identify the human Mediator complex as the transducer of activating ncRNAs and highlight the importance of Mediator and activating ncRNA association in human disease.