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Sample records for persistent enos activation

  1. A Maillard reaction product enhances eNOS activity in human endothelial cells.

    PubMed

    Schmitt, Christoph A; Heiss, Elke H; Schachner, Daniel; Aristei, Yasmin; Severin, Theodor; Dirsch, Verena M

    2010-07-01

    Nitric oxide (NO) produced by the endothelial nitric oxide synthase (eNOS) is an important signaling molecule in the cardiovascular system. Although dietary factors can modulate eNOS activity, putative effects of processed food are barely investigated. We aimed to examine whether the model Maillard reaction product 3-hydroxy-2-methyl-1-propyl-4(1H)-pyridone (HMPP), formed from maltol or starch and propylamine, affects the eNOS system. Incubation of EA.hy926 endothelial cells with 30-300 microM HMPP for 18 h enhanced endothelial NO release measured with the fluorescent probe diaminofluorescein-2 and eNOS activity determined by the [14C]L-arginine-[14C]L-citrulline conversion assay. HMPP increased NO production also in two different types of primary human endothelial cells. Protein levels of eNOS and inducible NO synthase remained unaltered by HMPP. HMPP inhibited eNOS activity within the first 2-4 h, whereas it potently increased eNOS activity after 12-24 h. Levels of eNOS phosphorylation, expression of heat-shock protein 90, caveolin-1 and various antioxidant enzymes were not affected. Intracellular reactive oxygen species remained unchanged by HMPP. This is the first study to demonstrate positive effects of a Maillard reaction product on eNOS activity and endothelial NO production, which is considered favourable for cardiovascular protection. PMID:20112298

  2. Role of SIRT1 and FOXO factors in eNOS transcriptional activation by resveratrol.

    PubMed

    Xia, Ning; Strand, Susanne; Schlufter, Frank; Siuda, Daniel; Reifenberg, Gisela; Kleinert, Hartmut; Förstermann, Ulrich; Li, Huige

    2013-08-01

    Many of the cardiovascular protective effects of resveratrol are attributable to an enhanced production of nitric oxide (NO) by the endothelial NO synthase (eNOS). Resveratrol has been shown to enhance eNOS gene expression as well as eNOS enzymatic activity. The aim of the present study was to analyze the molecular mechanisms of eNOS transcriptional activation by resveratrol. Treatment of human EA.hy 926 endothelial cells with resveratrol led to a concentration-dependent upregulation of eNOS expression. In luciferase reporter gene assay, resveratrol enhanced the activity of human eNOS promoter fragments (3500, 1600, 633 and 263bp in length, respectively), indicating that the proximal promoter region is required for resveratrol-induced eNOS transcriptional activation. Knockdown of the NAD(+)-dependent protein deacetylase sirtuin 1 (SIRT1) by siRNA prevented the upregulation of eNOS mRNA and protein by resveratrol. Forkhead box O (FOXO) transcription factors are established downstream targets of SIRT1. siRNA-mediated knockdown of FOXO1 and FOXO3a abolished the effect of resveratrol on eNOS expression, indicating the involvement of these factors. Resveratrol treatment enhanced the expression of FOXO1 and FOXO3a in EA.hy 926 cells. Reporter gene assay using promoter containing forkhead response elements showed increased FOXO factor activity by resveratrol. In electrophoretic mobility shift assay, the enhanced binding of nuclear proteins to the eNOS promoter regions by resveratrol could be blocked by antibodies against FOXO1 and FOXO3a. In conclusion, resveratrol enhances the expression and activity of FOXO transcription factors. The SIRT1/FOXO factor axis is involved in resveratrol-induced eNOS transcriptional activation.

  3. Stromal cell-derived factor 2 is critical for Hsp90-dependent eNOS activation.

    PubMed

    Siragusa, Mauro; Fröhlich, Florian; Park, Eon Joo; Schleicher, Michael; Walther, Tobias C; Sessa, William C

    2015-08-18

    Endothelial nitric oxide synthase (eNOS) catalyzes the conversion of l-arginine and molecular oxygen into l-citrulline and nitric oxide (NO), a gaseous second messenger that influences cardiovascular physiology and disease. Several mechanisms regulate eNOS activity and function, including phosphorylation at Ser and Thr residues and protein-protein interactions. Combining a tandem affinity purification approach and mass spectrometry, we identified stromal cell-derived factor 2 (SDF2) as a component of the eNOS macromolecular complex in endothelial cells. SDF2 knockdown impaired agonist-stimulated NO synthesis and decreased the phosphorylation of eNOS at Ser(1177), a key event required for maximal activation of eNOS. Conversely, SDF2 overexpression dose-dependently increased NO synthesis through a mechanism involving Akt and calcium (induced with ionomycin), which increased the phosphorylation of Ser(1177) in eNOS. NO synthesis by iNOS (inducible NOS) and nNOS (neuronal NOS) was also enhanced upon SDF2 overexpression. We found that SDF2 was a client protein of the chaperone protein Hsp90, interacting preferentially with the M domain of Hsp90, which is the same domain that binds to eNOS. In endothelial cells exposed to vascular endothelial growth factor (VEGF), SDF2 was required for the binding of Hsp90 and calmodulin to eNOS, resulting in eNOS phosphorylation and activation. Thus, our data describe a function for SDF2 as a component of the Hsp90-eNOS complex that is critical for signal transduction in endothelial cells. PMID:26286023

  4. Stromal cell–derived factor 2 is critical for Hsp90-dependent eNOS activation

    PubMed Central

    Siragusa, Mauro; Fröhlich, Florian; Park, Eon Joo; Schleicher, Michael; Walther, Tobias C.; Sessa, William C.

    2016-01-01

    Endothelial nitric oxide synthase (eNOS) catalyzes the conversion of l-arginine and molecular oxygen into l-citrulline and nitric oxide (NO), a gaseous second messenger that influences cardiovascular physiology and disease. Several mechanisms regulate eNOS activity and function, including phosphorylation at Ser and Thr residues and protein-protein interactions. Combining a tandem affinity purification approach and mass spectrometry, we identified stromal cell–derived factor 2 (SDF2) as a component of the eNOS macromolecular complex in endothelial cells. SDF2 knockdown impaired agonist-stimulated NO synthesis and decreased the phosphorylation of eNOS at Ser1177, a key event required for maximal activation of eNOS. Conversely, SDF2 overexpression dose-dependently increased NO synthesis through a mechanism involving Akt and calcium (induced with ionomycin), which increased the phosphorylation of Ser1177 in eNOS. NO synthesis by iNOS (inducible NOS) and nNOS (neuronal NOS) was also enhanced upon SDF2 overexpression. We found that SDF2 was a client protein of the chaperone protein Hsp90, interacting preferentially with the M domain of Hsp90, which is the same domain that binds to eNOS. In endothelial cells exposed to vascular endothelial growth factor (VEGF), SDF2 was required for the binding of Hsp90 and calmodulin to eNOS, resulting in eNOS phosphorylation and activation. Thus, our data describe a function for SDF2 as a component of the Hsp90-eNOS complex that is critical for signal transduction in endothelial cells. PMID:26286023

  5. Fenofibrate activates AMPK and increases eNOS phosphorylation in HUVEC

    SciTech Connect

    Murakami, Hisashi; Murakami, Ryuichiro . E-mail: ryuichi@med.nagoya-u.ac.jp; Kambe, Fukushi; Cao, Xia; Takahashi, Ryotaro; Asai, Toru; Hirai, Toshihisa; Numaguchi, Yasushi; Okumura, Kenji; Seo, Hisao; Murohara, Toyoaki

    2006-03-24

    Fenofibrate improves endothelial function by lipid-lowering and anti-inflammatory effects. Additionally, fenofibrate has been demonstrated to upregulate endothelial nitric oxide synthase (eNOS). AMP-activated protein kinase (AMPK) has been reported to phosphorylate eNOS at Ser-1177 and stimulate vascular endothelium-derived nitric oxide (NO) production. We report here that fenofibrate activates AMPK and increases eNOS phosphorylation and NO production in human umbilical vein endothelial cells (HUVEC). Incubation of HUVEC with fenofibrate increased the phosphorylation of AMPK and acetyl-CoA carboxylase. Fenofibrate simultaneously increased eNOS phosphorylation and NO production. Inhibitors of protein kinase A and phosphatidylinositol 3-kinase failed to suppress the fenofibrate-induced eNOS phosphorylation. Neither bezafibrate nor WY-14643 activated AMPK in HUVEC. Furthermore, fenofibrate activated AMPK without requiring any transcriptional activities. These results indicate that fenofibrate stimulates eNOS phosphorylation and NO production through AMPK activation, which is suggested to be a novel characteristic of this agonist and unrelated to its effects on peroxisome proliferator-activated receptor {alpha}.

  6. Activation of Endothelial Nitric Oxide (eNOS) Occurs through Different Membrane Domains in Endothelial Cells.

    PubMed

    Tran, Jason; Magenau, Astrid; Rodriguez, Macarena; Rentero, Carles; Royo, Teresa; Enrich, Carlos; Thomas, Shane R; Grewal, Thomas; Gaus, Katharina

    2016-01-01

    Endothelial cells respond to a large range of stimuli including circulating lipoproteins, growth factors and changes in haemodynamic mechanical forces to regulate the activity of endothelial nitric oxide synthase (eNOS) and maintain blood pressure. While many signalling pathways have been mapped, the identities of membrane domains through which these signals are transmitted are less well characterized. Here, we manipulated bovine aortic endothelial cells (BAEC) with cholesterol and the oxysterol 7-ketocholesterol (7KC). Using a range of microscopy techniques including confocal, 2-photon, super-resolution and electron microscopy, we found that sterol enrichment had differential effects on eNOS and caveolin-1 (Cav1) colocalisation, membrane order of the plasma membrane, caveolae numbers and Cav1 clustering. We found a correlation between cholesterol-induced condensation of the plasma membrane and enhanced high density lipoprotein (HDL)-induced eNOS activity and phosphorylation suggesting that cholesterol domains, but not individual caveolae, mediate HDL stimulation of eNOS. Vascular endothelial growth factor (VEGF)-induced and shear stress-induced eNOS activity was relatively independent of membrane order and may be predominantly controlled by the number of caveolae on the cell surface. Taken together, our data suggest that signals that activate and phosphorylate eNOS are transmitted through distinct membrane domains in endothelial cells.

  7. Activation of Endothelial Nitric Oxide (eNOS) Occurs through Different Membrane Domains in Endothelial Cells.

    PubMed

    Tran, Jason; Magenau, Astrid; Rodriguez, Macarena; Rentero, Carles; Royo, Teresa; Enrich, Carlos; Thomas, Shane R; Grewal, Thomas; Gaus, Katharina

    2016-01-01

    Endothelial cells respond to a large range of stimuli including circulating lipoproteins, growth factors and changes in haemodynamic mechanical forces to regulate the activity of endothelial nitric oxide synthase (eNOS) and maintain blood pressure. While many signalling pathways have been mapped, the identities of membrane domains through which these signals are transmitted are less well characterized. Here, we manipulated bovine aortic endothelial cells (BAEC) with cholesterol and the oxysterol 7-ketocholesterol (7KC). Using a range of microscopy techniques including confocal, 2-photon, super-resolution and electron microscopy, we found that sterol enrichment had differential effects on eNOS and caveolin-1 (Cav1) colocalisation, membrane order of the plasma membrane, caveolae numbers and Cav1 clustering. We found a correlation between cholesterol-induced condensation of the plasma membrane and enhanced high density lipoprotein (HDL)-induced eNOS activity and phosphorylation suggesting that cholesterol domains, but not individual caveolae, mediate HDL stimulation of eNOS. Vascular endothelial growth factor (VEGF)-induced and shear stress-induced eNOS activity was relatively independent of membrane order and may be predominantly controlled by the number of caveolae on the cell surface. Taken together, our data suggest that signals that activate and phosphorylate eNOS are transmitted through distinct membrane domains in endothelial cells. PMID:26977592

  8. (−)-Epicatechin activation of endothelial cell eNOS, NO and related signaling pathways

    PubMed Central

    Ramirez-Sanchez, Israel; Maya, Lisandro; Ceballos, Guillermo; Villarreal, Francisco

    2010-01-01

    Recent reports indicate that (−)-epicatechin can exert cardioprotective actions, which may involve eNOS-mediated nitric oxide production in endothelial cells. However, the mechanism by which (−)-epicatechin activates eNOS remains unclear. In this study, we proposed to identify the intracellular pathways involved in (−)-epicatechin-induced effects on eNOS, utilizing human coronary artery endothelial cells in culture. Treatment of cells with (−)-epicatechin leads to time- and dose-dependent effects, which peaked at 10 min at 1 μmol/L. (−)-Epicatechin treatment activates eNOS via serine-633 and serine-1177 phosphorylation and threonine-495 dephosphorylation. Using specific inhibitors, we have established the participation of the PI3K pathway in eNOS activation. (−)-Epicatechin induces eNOS uncoupling from caveolin-1 and its association with calmodulin-1, suggesting the involvement of intracellular calcium. These results allowed us to propose that (−) epicatechin effects may be dependent on actions exerted at the cell membrane level. To test this hypothesis, cells were treated with the phospholipase C inhibitor U73122, which blocked (−)-epicatechin-induced eNOS activation. We also demonstrated inositol phosphate accumulation in (−)-epicatechin-treated cells. The inhibitory effects of the pre-incubation of cells with the CaMKII inhibitor KN-93 indicate that (−)-epicatechin-induced eNOS activation is at least partially mediated via the Ca2+/CaMKII pathway. The (−)-epicatechin stereoisomer catechin was only able to partially stimulate nitric oxide production in cells. Altogether, these results strongly suggest the presence of a cell surface acceptor-effector for the cacao flavanol (−)-epicatechin, which may mediate its cardiovascular effects. PMID:20404222

  9. (−)-Epicatechin induces calcium and translocation independent eNOS activation in arterial endothelial cells

    PubMed Central

    Ramirez-Sanchez, Israel; Maya, Lisandro; Ceballos, Guillermo

    2011-01-01

    The consumption of cacao-derived (i.e., cocoa) products provides beneficial cardiovascular effects in healthy subjects as well as individuals with endothelial dysfunction such as smokers, diabetics, and postmenopausal women. The vascular actions of cocoa are related to enhanced nitric oxide (NO) production. These actions can be reproduced by the administration of the cacao flavanol (−)-epicatechin (EPI). To further understand the mechanisms behind the vascular action of EPI, we investigated the effects of Ca2+ depletion on endothelial nitric oxide (NO) synthase (eNOS) activation/phosphorylation and translocation. Human coronary artery endothelial cells were treated with EPI or with bradykinin (BK), a well-known Ca2+-dependent eNOS activator. Results demonstrate that both EPI and BK induce increases in intracellular calcium and NO levels. However, under Ca2+-free conditions, EPI (but not BK) is still capable of inducing NO production through eNOS phosphorylation at serine 615, 633, and 1177. Interestingly, EPI-induced translocation of eNOS from the plasmalemma was abolished upon Ca2+ depletion. Thus, under Ca2+-free conditions, EPI can stimulate NO synthesis independent of calmodulin binding to eNOS and of its translocation into the cytoplasm. We also examined the effect of EPI on the NO/cGMP/vasodilator-stimulated phosphoprotein (VASP) pathway activation in isolated Ca2+-deprived canine mesenteric arteries. Results demonstrate that under these conditions, EPI induces the activation of this vasorelaxation-related pathway and that this effect is inhibited by pretreatment with nitro-l-arginine methyl ester, suggesting a functional relevance for this phenomenon. PMID:21209365

  10. Activation of eNOS in endothelial cells exposed to ionizing radiation involves components of the DNA damage response pathway

    SciTech Connect

    Nagane, Masaki; Yasui, Hironobu; Sakai, Yuri; Yamamori, Tohru; Niwa, Koichi; Hattori, Yuichi; Kondo, Takashi; Inanami, Osamu

    2015-01-02

    Highlights: • eNOS activity is increased in BAECs exposed to X-rays. • ATM is involved in this increased eNOS activity. • HSP90 modulates the radiation-induced activation of ATM and eNOS. - Abstract: In this study, the involvement of ataxia telangiectasia mutated (ATM) kinase and heat shock protein 90 (HSP90) in endothelial nitric oxide synthase (eNOS) activation was investigated in X-irradiated bovine aortic endothelial cells. The activity of nitric oxide synthase (NOS) and the phosphorylation of serine 1179 of eNOS (eNOS-Ser1179) were significantly increased in irradiated cells. The radiation-induced increases in NOS activity and eNOS-Ser1179 phosphorylation levels were significantly reduced by treatment with either an ATM inhibitor (Ku-60019) or an HSP90 inhibitor (geldanamycin). Geldanamycin was furthermore found to suppress the radiation-induced phosphorylation of ATM-Ser1181. Our results indicate that the radiation-induced eNOS activation in bovine aortic endothelial cells is regulated by ATM and HSP90.

  11. Polymorphisms of the eNOS gene are associated with disease activity in rheumatoid arthritis.

    PubMed

    Bunjevacki, Vera; Maksimovic, Nela; Jekic, Biljana; Milic, Vera; Lukovic, Ljiljana; Novakovic, Ivana; Damjanov, Nemanja; Radunovic, Goran; Damnjanovic, Tatjana

    2016-04-01

    Nitric oxide (NO) is a mediator in autoimmune responses and thus involved in the pathogenesis of a variety of rheumatic diseases. Genetic factors that influence the expression of the enzyme endothelial nitric oxide synthase (eNOS) that catalyzes NO synthesis are important for the control of NO level and consequently its activity. We have analyzed three functionally relevant polymorphisms of eNOS gene: T-786C, G894T and VNTR (4a/b), to investigate whether they are predisposing factors in pathogenesis of RA in Serbian population and to evaluate their role in clinical manifestations of RA. We performed genotyping of 196 patients with RA and the control group of 132 healthy individuals from Serbian population, using PCR and polymerase chain reaction-restriction fragment length polymorphism methods. Disease activity was prospectively assessed using number of tender joints, number of swollen joints and 28-joints disease activity score (DAS28). There were no differences between the patients and control groups in the genotypes and alleles frequencies of the three analyzed SNPs. Our results showed statistically significant differences in all three analyzed parameters of disease severity between 786TT/786CT and 786CC genotypes and between 894GG/894GT and 894TT genotypes. In the case of 4a/b polymorphism, carriers of minor allele had significantly lower DAS28 values. In conclusion, our results do not support the implication of analyzed eNOS gene polymorphisms in susceptibility to RA but associate them with the disease activity and give assumption that minor alleles are indicators of better clinical course. PMID:26612436

  12. Serum from Calorie-Restricted Rats Activates Vascular Cell eNOS through Enhanced Insulin Signaling Mediated by Adiponectin

    PubMed Central

    Cerqueira, Fernanda M.; Brandizzi, Laura I.; Cunha, Fernanda M.; Laurindo, Francisco R. M.; Kowaltowski, Alicia J.

    2012-01-01

    eNOS activation resulting in mitochondrial biogenesis is believed to play a central role in life span extension promoted by calorie restriction (CR). We investigated the mechanism of this activation by treating vascular cells with serum from CR rats and found increased Akt and eNOS phosphorylation, in addition to enhanced nitrite release. Inhibiting Akt phosphorylation or immunoprecipitating adiponectin (found in high quantities in CR serum) completely prevented the increment in nitrite release and eNOS activation. Overall, we demonstrate that adiponectin in the serum from CR animals increases NO• signaling by activating the insulin pathway. These results suggest this hormone may be a determinant regulator of the beneficial effects of CR. PMID:22319612

  13. Phenylephrine activates eNOS Ser 1177 phosphorylation and nitric oxide signaling in renal hypertensive rat aorta.

    PubMed

    Silva, Bruno R; Pernomian, Laena; Grando, Marcella D; Bendhack, Lusiane M

    2014-09-01

    The endothelial nitric oxide synthase (eNOS) plays an important role in the control of the vascular tone. This work aimed to evaluate the role of an α1-adrenoceptor agonist phenylephrine (PE) on eNOS activity and downstream signaling pathway activation in normotensive (2K) and renal hypertensive (2K-1C) intact-endothelium rat aortas. Concentration-effect curves were performed for PE in intact-endothelium aortas from 2K and 2K-1C rats, in the absence of or in the presence of NOS or soluble guanylyl cyclase (sGC) inhibitor. Intact endothelium aortas were stimulated with PE in organ chambers and eNOS Ser(1177)/Thr(495) phosphorylation expression was evaluated by western blot. Nitric Oxide (NO) production was evaluated in isolated endothelial cells from 2K and 2K-1C rat aortas by flow-cytometry using NO selective fluorescent probe, DAF-2DA. The sGC activity/expression was also evaluated. PE-induced contractile response is lower in 2K-1C than in 2K intact-endothelium rat aorta. This is due to higher eNOS Ser(1177) phosphorylation in 2K-1C, which induces the eNOS overactivation. It was abolished by NOS or sGC inhibition. Phenylephrine reduces NO production in 2K as compared to the basal level, but it is not modified in 2K-1C. In PE-stimulated endothelial cells, the NO production is higher in 2K-1C than in 2K. Phenylephrine induces higher cGMP production in 2K-1C than in 2K, despite the lower expression of sGC in 2K-1C. Our results suggest that alpha1-adrenoceptor activation contributes to the increased activity of the enzyme eNOS by Ser(1177) phosphorylation in 2K-1C intact-endothelium aorta, which consequently decreases PE-induced contractile response.

  14. Sildenafil Promotes eNOS Activation and Inhibits NADPH Oxidase in the Transgenic Sickle Cell Mouse Penis

    PubMed Central

    Musicki, Biljana; Bivalacqua, Trinity J.; Champion, Hunter C.; Burnett, Arthur L.

    2014-01-01

    Introduction Sickle cell disease (SCD)-associated vasculopathy in the penis is characterized by aberrant nitric oxide and phosphodiesterase (PDE) 5 signaling, and by increased oxidative stress. Preliminary clinical trials show that continuous treatment with PDE5 inhibitor sildenafil unassociated with sexual activity decreases priapic activity in patients with SCD. However, the mechanism of its vasculoprotective effect in the penis remains unclear. Aims We evaluated whether continuous administration of PDE5 inhibitor sildenafil promotes eNOS function at posttranslational levels and decreases superoxide-producing enzyme NADPH oxidase activity in the sickle cell mouse penis. Methods SCD transgenic mice were used as an animal model of SCD. WT mice served as controls. Mice received treatment with the PDE5 inhibitor sildenafil (100 mg/kg/day) or vehicle for 3 weeks. eNOS phosphorylation on Ser-1177 (positive regulatory site), eNOS interactions with heat-shock protein 90 (HSP90) (positive regulator), phosphorylated AKT (upstream mediator of eNOS phosphorylation on Ser-1177), an NADPH oxidase catalytic subunit gp91(phox), and a marker of oxidative stress (4-hydroxy-2-nonenal [HNE]) were measured by Western blot. Main Outcome Measures Effect of continuous sildenafil treatment on eNOS posttranslational activation, NADPH oxidase catalytic subunit, and oxidative stress in the penis of the sickle cell mouse. Results Continuous treatment with sildenafil reversed (P < 0.05) the abnormalities in protein expressions of P-eNOS (Ser-1177), eNOS/HSP90 interaction, P-AKT, protein expression of gp91(phox), and 4-HNE, in the sickle cell mouse penis. Sildenafil treatment of WT mice did not affect any of these parameters. Conclusion Our findings that sildenafil enhances eNOS activation and inhibits NADPH oxidase function in the sickle cell mouse penis offers a vasculoprotective molecular basis for the therapeutic effect of sildenafil in the penis in association with SCD. PMID:24251665

  15. Triterpenoic Acids from Apple Pomace Enhance the Activity of the Endothelial Nitric Oxide Synthase (eNOS).

    PubMed

    Waldbauer, Katharina; Seiringer, Günter; Nguyen, Dieu Linh; Winkler, Johannes; Blaschke, Michael; McKinnon, Ruxandra; Urban, Ernst; Ladurner, Angela; Dirsch, Verena M; Zehl, Martin; Kopp, Brigitte

    2016-01-13

    Pomace is an easy-accessible raw material for the isolation of fruit-derived compounds. Fruit consumption is associated with health-promoting effects, such as the prevention of cardiovascular disease. Increased vascular nitric oxide (NO) bioavailability, for example, due to an enhanced endothelial nitric oxide synthase (eNOS) activity, could be one molecular mechanism mediating this effect. To identify compounds from apple (Malus domestica Borkh.) pomace that have the potential to amplify NO bioavailability via eNOS activation, a bioassay-guided fractionation of the methanol/water (70:30) extract has been performed using the (14)C-L-arginine to (14)C-L-citrulline conversion assay (ACCA) in the human endothelium-derived cell line EA.hy926. Phytochemical characterization of the active fractions was performed using the spectrophotometric assessment of the total phenolic content, as well as TLC, HPLC-DAD-ELSD, and HPLC-MS analyses. Eleven triterpenoic acids, of which one is a newly discovered compound, were identified as the main constituents in the most active fraction, accompanied by only minor contents of phenolic compounds. When tested individually, none of the tested compounds exhibited significant eNOS activation. Nevertheless, cell stimulation with the reconstituted compound mixture restored eNOS activation, validating the potential of apple pomace as a source of bioactive components.

  16. Pretreatment with β-Boswellic Acid Improves Blood Stasis Induced Endothelial Dysfunction: Role of eNOS Activation.

    PubMed

    Wang, Mingming; Chen, Minchun; Ding, Yi; Zhu, Zhihui; Zhang, Yikai; Wei, Peifeng; Wang, Jingwen; Qiao, Yi; Li, Liang; Li, Yuwen; Wen, Aidong

    2015-01-01

    Vascular endothelial cells play an important role in modulating anti-thrombus and maintaining the natural function of vascular by secreting many active substances. β-boswellic acid (β-BA) is an active triterpenoid compound from the extract of boswellia serrate. In this study, it is demonstrated that β-BA ameliorates plasma coagulation parameters, protects endothelium from blood stasis induced injury and prevents blood stasis induced impairment of endothelium-dependent vasodilatation. Moreover, it is found that β-BA significantly increases nitric oxide (NO) and cyclic guanosine 3', 5'-monophosphate (cGMP) levels in carotid aortas of blood stasis rats. To stimulate blood stasis-like conditions in vitro, human umbilical vein endothelial cells (HUVECs) were exposed to transient oxygen and glucose deprivation (OGD). Treatment of β-BA significantly increased intracellular NO level. Western blot and immunofluorescence as well as immunohistochemistry reveal that β-BA increases phosphorylation of enzyme nitric oxide synthase (eNOS) at Ser1177. In addition, β-BA mediated endothelium-dependent vasodilatation can be markedly blocked by eNOS inhibitor L-NAME in blood stasis rats. In OGD treated HUEVCs, the protective effect of β-BA is attenuated by knockdown of eNOS. In conclusion, the above findings provide convincing evidence for the protective effects of β-BA on blood stasis induced endothelial dysfunction by eNOS signaling pathway. PMID:26482008

  17. Pretreatment with β-Boswellic Acid Improves Blood Stasis Induced Endothelial Dysfunction: Role of eNOS Activation

    PubMed Central

    Wang, Mingming; Chen, Minchun; Ding, Yi; Zhu, Zhihui; Zhang, Yikai; Wei, Peifeng; Wang, Jingwen; Qiao, Yi; Li, Liang; Li, Yuwen; Wen, Aidong

    2015-01-01

    Vascular endothelial cells play an important role in modulating anti-thrombus and maintaining the natural function of vascular by secreting many active substances. β-boswellic acid (β-BA) is an active triterpenoid compound from the extract of boswellia serrate. In this study, it is demonstrated that β-BA ameliorates plasma coagulation parameters, protects endothelium from blood stasis induced injury and prevents blood stasis induced impairment of endothelium-dependent vasodilatation. Moreover, it is found that β-BA significantly increases nitric oxide (NO) and cyclic guanosine 3’, 5’-monophosphate (cGMP) levels in carotid aortas of blood stasis rats. To stimulate blood stasis-like conditions in vitro, human umbilical vein endothelial cells (HUVECs) were exposed to transient oxygen and glucose deprivation (OGD). Treatment of β-BA significantly increased intracellular NO level. Western blot and immunofluorescence as well as immunohistochemistry reveal that β-BA increases phosphorylation of enzyme nitric oxide synthase (eNOS) at Ser1177. In addition, β-BA mediated endothelium-dependent vasodilatation can be markedly blocked by eNOS inhibitor L-NAME in blood stasis rats. In OGD treated HUEVCs, the protective effect of β-BA is attenuated by knockdown of eNOS. In conclusion, the above findings provide convincing evidence for the protective effects of β-BA on blood stasis induced endothelial dysfunction by eNOS signaling pathway. PMID:26482008

  18. Human red blood cells at work: identification and visualization of erythrocytic eNOS activity in health and disease.

    PubMed

    Cortese-Krott, Miriam M; Rodriguez-Mateos, Ana; Sansone, Roberto; Kuhnle, Gunter G C; Thasian-Sivarajah, Sivatharsini; Krenz, Thomas; Horn, Patrick; Krisp, Christoph; Wolters, Dirk; Heiß, Christian; Kröncke, Klaus-Dietrich; Hogg, Neil; Feelisch, Martin; Kelm, Malte

    2012-11-15

    A nitric oxide synthase (NOS)-like activity has been demonstrated in human red blood cells (RBCs), but doubts about its functional significance, isoform identity and disease relevance remain. Using flow cytometry in combination with the nitric oxide (NO)-imaging probe DAF-FM we find that all blood cells form NO intracellularly, with a rank order of monocytes > neutrophils > lymphocytes > RBCs > platelets. The observation of a NO-related fluorescence within RBCs was unexpected given the abundance of the NO-scavenger oxyhemoglobin. Constitutive normoxic NO formation was abolished by NOS inhibition and intracellular NO scavenging, confirmed by laser-scanning microscopy and unequivocally validated by detection of the DAF-FM reaction product with NO using HPLC and LC-MS/MS. Using immunoprecipitation, ESI-MS/MS-based peptide sequencing and enzymatic assay we further demonstrate that human RBCs contain an endothelial NOS (eNOS) that converts L-(3)H-arginine to L-(3)H-citrulline in a Ca(2+)/calmodulin-dependent fashion. Moreover, in patients with coronary artery disease, red cell eNOS expression and activity are both lower than in age-matched healthy individuals and correlate with the degree of endothelial dysfunction. Thus, human RBCs constitutively produce NO under normoxic conditions via an active eNOS isoform, the activity of which is compromised in patients with coronary artery disease.

  19. Role of PECAM-1 in the shear-stress-induced activation of Akt and the endothelial nitric oxide synthase (eNOS) in endothelial cells.

    PubMed

    Fleming, Ingrid; Fisslthaler, Beate; Dixit, Madhulika; Busse, Rudi

    2005-09-15

    The application of fluid shear stress to endothelial cells elicits the formation of nitric oxide (NO) and phosphorylation of the endothelial NO synthase (eNOS). Shear stress also elicits the enhanced tyrosine phosphorylation of endothelial proteins, especially of those situated in the vicinity of cell-cell contacts. Since a major constituent of these endothelial cell-cell contacts is the platelet endothelial cell adhesion molecule-1 (PECAM-1) we assessed the role of PECAM-1 in the activation of eNOS. In human endothelial cells, shear stress induced the tyrosine phosphorylation of PECAM-1 and enhanced the association of PECAM-1 with eNOS. Endothelial cell stimulation with shear stress elicited the phosphorylation of Akt and eNOS as well as of the AMP-activated protein kinase (AMPK). While the shear-stress-induced tyrosine phosphorylation of PECAM-1 as well as the serine phosphorylation of Akt and eNOS were abolished by the pre-treatment of cells with the tyrosine kinase inhibitor PP1 the phosphorylation of AMPK was unaffected. Down-regulation of PECAM-1 using a siRNA approach attenuated the shear-stress-induced phosphorylation of Akt and eNOS, as well as the shear-stress-induced accumulation of cyclic GMP levels while the shear-stress-induced phosphorylation of AMPK remained intact. A comparable attenuation of Akt and eNOS (but not AMPK) phosphorylation and NO production was also observed in endothelial cells generated from PECAM-1-deficient mice. These data indicate that the shear-stress-induced activation of Akt and eNOS in endothelial cells is modulated by the tyrosine phosphorylation of PECAM-1 whereas the shear-stress-induced phosphorylation of AMPK is controlled by an alternative signaling pathway. PMID:16118242

  20. ENO2 activity is required for the development and reproductive success of plants, and is feedback-repressed by AtMBP-1.

    PubMed

    Eremina, Marina; Rozhon, Wilfried; Yang, Saiqi; Poppenberger, Brigitte

    2015-03-01

    Enolases are key glycolytic enzymes that are highly conserved in prokaryotic and eukaryotic organisms, and are among the most abundant cytosolic proteins. In this study we provide evidence that activity of the enolase ENO2 is essential for the growth and development of plants. We show that Arabidopsis plants with compromised ENO2 function, which were generated by mutating the LOS2/ENO2 locus, have severe cellular defects, including reduced cell size and defective cell differentiation with restricted lignification. At the tissue and organ level LOS2/ENO2-deficient plants are characterized by the reduced growth of shoots and roots, altered vascular development and defective secondary growth of stems, impaired floral organogenesis and defective male gametophyte function, resulting in embryo lethality as well as delayed senescence. These phenotypes correlate with reduced lignin and increased salicylic acid contents as well as altered fatty acid and soluble sugar composition. In addition to an enolase the LOS2/ENO2 locus encodes the transcription factor AtMBP-1, and here we reveal that this bifunctionality serves to maintain the homeostasis of ENO2 activity. In summary, we show that in plants enolase function is required for the formation of chorismate-dependent secondary metabolites, and that this activity is feedback-inhibited by AtMBP-1 to enable the normal development and reproductive success of plants.

  1. Purinergic glio-endothelial coupling during neuronal activity: role of P2Y1 receptors and eNOS in functional hyperemia in the mouse somatosensory cortex.

    PubMed

    Toth, Peter; Tarantini, Stefano; Davila, Antonio; Valcarcel-Ares, M Noa; Tucsek, Zsuzsanna; Varamini, Behzad; Ballabh, Praveen; Sonntag, William E; Baur, Joseph A; Csiszar, Anna; Ungvari, Zoltan

    2015-12-01

    Impairment of moment-to-moment adjustment of cerebral blood flow (CBF) via neurovascular coupling is thought to play a critical role in the genesis of cognitive impairment associated with aging and pathological conditions associated with accelerated cerebromicrovascular aging (e.g., hypertension, obesity). Although previous studies demonstrate that endothelial dysfunction plays a critical role in neurovascular uncoupling in these conditions, the role of endothelial NO mediation in neurovascular coupling responses is not well understood. To establish the link between endothelial function and functional hyperemia, neurovascular coupling responses were studied in mutant mice overexpressing or deficient in endothelial NO synthase (eNOS), and the role of P2Y1 receptors in purinergic glioendothelial coupling was assessed. We found that genetic depletion of eNOS (eNOS(-/-)) and pharmacological inhibition of NO synthesis significantly decreased the CBF responses in the somatosensory cortex evoked by whisker stimulation and by administration of ATP. Overexpression of eNOS enhanced NO mediation of functional hyperemia. In control mice, the selective and potent P2Y1 receptor antagonist MRS2179 attenuated both whisker stimulation-induced and ATP-mediated CBF responses, whereas, in eNOS(-/-) mice, the inhibitory effects of MRS2179 were blunted. Collectively, our findings provide additional evidence for purinergic glio-endothelial coupling during neuronal activity, highlighting the role of ATP-mediated activation of eNOS via P2Y1 receptors in functional hyperemia. PMID:26453330

  2. Sodium nitrite exerts an antihypertensive effect and improves endothelial function through activation of eNOS in the SHR.

    PubMed

    Ling, Wei Chih; Murugan, Dharmani Devi; Lau, Yeh Siang; Vanhoutte, Paul M; Mustafa, Mohd Rais

    2016-01-01

    Sodium nitrite (NaNO2) induces relaxation in isolated arteries partly through an endothelium-dependent mechanism involving NO-eNOS-sGC-cGMP pathway. The present study was designed to investigate the effect of chronic NaNO2 administration on arterial systolic blood pressure (SBP) and vascular function in hypertensive rats. NaNO2 (150 mg L-1) was given in drinking water for four weeks to spontaneously (SHR) and Nω-Nitro-L-arginine methyl ester hydrochloride (L-NAME) treated hypertensive SD rats. Arterial SBP and vascular function in isolated aortae were studied. Total plasma nitrate/nitrite and vascular cyclic guanosine monophosphate (cGMP) levels were measured using commercially available assay kits. Vascular nitric oxide (NO) levels were evaluated by DAF-FM fluorescence while the proteins involved in endothelial nitric oxide synthase (eNOS) activation was determined by Western blotting. NaNO2 treatment reduced SBP, improved the impaired endothelium-dependent relaxation, increased plasma total nitrate/nitrite level and vascular tissue NO and cGMP levels in SHR. Furthermore, increased presence of phosphorylated eNOS and Hsp-90 was observed in NaNO2-treated SHR. The beneficial effect of nitrite treatment was not observed in L-NAME treated hypertensive SD rats. The present study provides evidence that chronic treatment of genetically hypertensive rats with NaNO2 improves endothelium-dependent relaxation in addition to its antihypertensive effect, partly through mechanisms involving activation of eNOS. PMID:27616322

  3. Sodium nitrite exerts an antihypertensive effect and improves endothelial function through activation of eNOS in the SHR

    PubMed Central

    Ling, Wei Chih; Murugan, Dharmani Devi; Lau, Yeh Siang; Vanhoutte, Paul M.; Mustafa, Mohd Rais

    2016-01-01

    Sodium nitrite (NaNO2) induces relaxation in isolated arteries partly through an endothelium-dependent mechanism involving NO-eNOS-sGC-cGMP pathway. The present study was designed to investigate the effect of chronic NaNO2 administration on arterial systolic blood pressure (SBP) and vascular function in hypertensive rats. NaNO2 (150 mg L−1) was given in drinking water for four weeks to spontaneously (SHR) and Nω-Nitro-L-arginine methyl ester hydrochloride (L-NAME) treated hypertensive SD rats. Arterial SBP and vascular function in isolated aortae were studied. Total plasma nitrate/nitrite and vascular cyclic guanosine monophosphate (cGMP) levels were measured using commercially available assay kits. Vascular nitric oxide (NO) levels were evaluated by DAF-FM fluorescence while the proteins involved in endothelial nitric oxide synthase (eNOS) activation was determined by Western blotting. NaNO2 treatment reduced SBP, improved the impaired endothelium-dependent relaxation, increased plasma total nitrate/nitrite level and vascular tissue NO and cGMP levels in SHR. Furthermore, increased presence of phosphorylated eNOS and Hsp-90 was observed in NaNO2-treated SHR. The beneficial effect of nitrite treatment was not observed in L-NAME treated hypertensive SD rats. The present study provides evidence that chronic treatment of genetically hypertensive rats with NaNO2 improves endothelium-dependent relaxation in addition to its antihypertensive effect, partly through mechanisms involving activation of eNOS. PMID:27616322

  4. NOX4-dependent Hydrogen peroxide promotes shear stress-induced SHP2 sulfenylation and eNOS activation.

    PubMed

    Sánchez-Gómez, Francisco J; Calvo, Enrique; Bretón-Romero, Rosa; Fierro-Fernández, Marta; Anilkumar, Narayana; Shah, Ajay M; Schröder, Katrin; Brandes, Ralf P; Vázquez, Jesús; Lamas, Santiago

    2015-12-01

    Laminar shear stress (LSS) triggers signals that ultimately result in atheroprotection and vasodilatation. Early responses are related to the activation of specific signaling cascades. We investigated the participation of redox-mediated modifications and in particular the role of hydrogen peroxide (H2O2) in the sulfenylation of redox-sensitive phosphatases. Exposure of vascular endothelial cells to short periods of LSS (12 dyn/cm(2)) resulted in the generation of superoxide radical anion as detected by the formation of 2-hydroxyethidium by HPLC and its subsequent conversion to H2O2, which was corroborated by the increase in the fluorescence of the specific peroxide sensor HyPer. By using biotinylated dimedone we detected increased total protein sulfenylation in the bovine proteome, which was dependent on NADPH oxidase 4 (NOX4)-mediated generation of peroxide. Mass spectrometry analysis allowed us to identify the phosphatase SHP2 as a protein susceptible to sulfenylation under LSS. Given the dependence of FAK activity on SHP2 function, we explored the role of FAK under LSS conditions. FAK activation and subsequent endothelial NO synthase (eNOS) phosphorylation were promoted by LSS and both processes were dependent on NOX4, as demonstrated in lung endothelial cells isolated from NOX4-null mice. These results support the idea that LSS elicits redox-sensitive signal transduction responses involving NOX4-dependent generation of hydrogen peroxide, SHP2 sulfenylation, and ulterior FAK-mediated eNOS activation.

  5. β3-Adrenoreceptor stimulation protects against myocardial infarction injury via eNOS and nNOS activation.

    PubMed

    Niu, Xiaolin; Zhao, Lianyou; Li, Xue; Xue, Yusheng; Wang, Bin; Lv, Zongqiang; Chen, Jianghong; Sun, Dongdong; Zheng, Qiangsun

    2014-01-01

    β3-adrenergic receptor (AR) and the downstream signaling, nitric oxide synthase (NOS) isoforms, have been emerged as novel modulators of heart function and even potential therapeutic targets for cardiovascular diseases. However, it is not known whether β3-AR plays cardioprotective effects against myocardial infarction (MI) injury. Therefore, the present study was designed to determine the effects of β3-AR on MI injury and to elucidate the underlying mechanism. MI model was constructed by left anterior descending (LAD) artery ligation. Animals were administrated with β3-AR agonist BRL37344 (BRL) or β3-AR inhibitor SR59230A (SR) respectively at 0.1 mg/kg/hour one day after MI operation. The scar area, cardiac function and the apoptosis of myocardial were assessed by Masson's trichrome stain, echocardiography and TUNEL assay respectively. Western blot analysis was performed to elucidate the expressions of target proteins. β3-AR activation with BRL administration significantly attenuated fibrosis and decreased scar area after MI. Moreover, BRL also preserved heart function, and reduced the apoptosis of cardiomyocyte induced by MI. Furthermore, BRL treatment altered the phosphorylation status of endothelial NOS (eNOS) and increased the expression of neuronal NOS (nNOS). These results suggested that β3-AR stimulation has a substantial effect on recovery of heart function. In addition, the activations of both eNOS and nNOS may be associated with the cardiac protective effects of β3-AR.

  6. Insulin resistance reduces arterial prostacyclin synthase and eNOS activities by increasing endothelial fatty acid oxidation

    PubMed Central

    Du, Xueliang; Edelstein, Diane; Obici, Silvana; Higham, Ninon; Zou, Ming-Hui; Brownlee, Michael

    2006-01-01

    Insulin resistance markedly increases cardiovascular disease risk in people with normal glucose tolerance, even after adjustment for known risk factors such as LDL, triglycerides, HDL, and systolic blood pressure. In this report, we show that increased oxidation of FFAs in aortic endothelial cells without added insulin causes increased production of superoxide by the mitochondrial electron transport chain. FFA-induced overproduction of superoxide activated a variety of proinflammatory signals previously implicated in hyperglycemia-induced vascular damage and inactivated 2 important antiatherogenic enzymes, prostacyclin synthase and eNOS. In 2 nondiabetic rodent models — insulin-resistant, obese Zucker (fa/fa) rats and high-fat diet–induced insulin-resistant mice — inactivation of prostacyclin synthase and eNOS was prevented by inhibition of FFA release from adipose tissue; by inhibition of the rate-limiting enzyme for fatty acid oxidation in mitochondria, carnitine palmitoyltransferase I; and by reduction of superoxide levels. These studies identify what we believe to be a novel mechanism contributing to the accelerated atherogenesis and increased cardiovascular disease risk occurring in people with insulin resistance. PMID:16528409

  7. Ubiad1 Is an Antioxidant Enzyme that Regulates eNOS Activity by CoQ10 Synthesis

    PubMed Central

    Mugoni, Vera; Postel, Ruben; Catanzaro, Valeria; De Luca, Elisa; Turco, Emilia; Digilio, Giuseppe; Silengo, Lorenzo; Murphy, Michael P.; Medana, Claudio; Stainier, Didier Y.R.; Bakkers, Jeroen; Santoro, Massimo M.

    2013-01-01

    Summary Protection against oxidative damage caused by excessive reactive oxygen species (ROS) by an antioxidant network is essential for the health of tissues, especially in the cardiovascular system. Here, we identified a gene with important antioxidant features by analyzing a null allele of zebrafish ubiad1, called barolo (bar). bar mutants show specific cardiovascular failure due to oxidative stress and ROS-mediated cellular damage. Human UBIAD1 is a nonmitochondrial prenyltransferase that synthesizes CoQ10 in the Golgi membrane compartment. Loss of UBIAD1 reduces the cytosolic pool of the antioxidant CoQ10 and leads to ROS-mediated lipid peroxidation in vascular cells. Surprisingly, inhibition of eNOS prevents Ubiad1-dependent cardiovascular oxidative damage, suggesting a crucial role for this enzyme and nonmitochondrial CoQ10 in NO signaling. These findings identify UBIAD1 as a nonmitochondrial CoQ10-forming enzyme with specific cardiovascular protective function via the modulation of eNOS activity. PMID:23374346

  8. Augmentation of platelet and endothelial cell eNOS activity decreases sepsis-related neutrophil-endothelial cell interactions.

    PubMed

    Khan, Raymond; Kirschenbaum, Linda A; LaRow, Catherine; Berna, Gioiamaria; Griffin, Kelly; Astiz, Mark E

    2010-03-01

    NO is an important mediator of microvascular patency and blood flow. The purpose of this study was to examine the role of enhanced eNOS activity in attenuating sepsis-induced neutrophil-endothelial cell interactions. Microslides coated with human umbilical vein endothelial cells were stimulated with plasma from patients with septic shock. Neutrophil and platelets from control subjects were also stimulated with plasma from patients in septic shock and perfused over stimulated endothelial cells. l-Arginine (LA) with and without NG-monomethyl l-arginine (LNMMA), a nonselective NOS inhibitor, and N-(3-(aminomethyl) benzyl acetamide) ethanimidamide dihydrochloride (1400W), a highly selective iNOS inhibitor, were added to the septic plasma. The number of neutrophils adherent to endothelial cells, neutrophil rolling velocity, and the number of neutrophil aggregates were determined. Cell activation and the formation of platelet-neutrophil aggregates were assessed by flow cytometry. Separate experiments were done with isolated platelets using platelet aggregometry. l-Arginine significantly decreased sepsis-related neutrophil adhesion and aggregation and increased rolling velocity. The addition of LNMMA to LA and cell suspensions reversed the effects of LA on these parameters, whereas the addition of 1400W had no effect on LA-related changes. Platelet-neutrophil aggregation, platelet aggregation, platelet activation, and neutrophil activation induced by septic plasma were also significantly decreased by LA. Again, the addition of LNMMA reversed the effects of LA on these parameters, whereas 1400W had no effect on LA-related changes. These data suggest that enhancement of platelet and endothelial cell eNOS activity decreases sepsis-induced neutrophil-endothelial cell interactions and may play a role in maintaining microvascular patency in septic shock.

  9. Differential Activation of Multiple Signaling Pathways Dictates eNOS Upregulation by FGF2 but not VEGF in Placental Artery Endothelial Cells1

    PubMed Central

    Mata-Greenwood, Eugenia; Liao, Wu-Xiang; Zheng, Jing; Chen, Dong-Bao

    2008-01-01

    Fibroblast growth factor (FGF2), but not vascular endothelial growth factor (VEGF), upregulates endothelial nitric oxide synthase (eNOS) protein expression, at least in part, via activation of extracellular signal-regulated kinase 2/1 (ERK2/1) in ovine fetoplacental artery endothelial (oFPAE) cells. Herein we further investigated the temporal effects of FGF2 and VEGF on other signaling pathways including members (Jun N-terminal kinase JNK1/2 and p38MAPK) of mitogen-activated protein kinases (MAPK), phosphatidylinositol 3 kinase/v-akt murine thymoma viral oncogene homolog 1 (PI3K/AKT1), and the tyrosine kinase c-SRC, and examined if either one or more of these pathways play a role in the differential regulation of eNOS by FGF2 and VEGF. We first confirmed that in oFPAE cells, FGF2, but not VEGF, increased eNOS protein. FGF2 stimulated eNOS protein in a time and concentration dependent manner, which also depended on cell density. FGF2 provoked sustained (5 min to 12 h) whereas VEGF only stimulated transient (5 min) ERK2/1 phosphorylation. FGF2 was 1.7-fold more potent in stimulating ERK2/1 phosphorylation than VEGF. FGF2 and VEGF only transiently activated JNK1/2 and AKT1 within 5 min; however, FGF2 was a stronger stimulus than VEGF. FGF2 and VEGF did not significantly activate p38MAPK at 5 min; however, VEGF stimulated p38MAPK phosphorylation at 60 min. VEGF but not FGF2 significantly stimulated c-SRC phosphorylation. Inhibitors of MEK-ERK2/1 (PD98059), JNK1/2 (SP600125) and PI3K (wortmannin), but not p38MAPK (SB203580) and SRC (PP2), decreased the FGF2-increased eNOS protein expression. Thus, the FGF2-induced eNOS protein expression requires activation of multiple signaling pathways including ERK2/1, JNK1/2 and PI3K/AKT1. Differences in intensity and temporal patterns of activation of these pathways by FGF2 and VEGF may account for their differential effects on eNOS expression in OFPAE cells. PMID:18571718

  10. Redox-Sensitive Induction of Src/PI3-kinase/Akt and MAPKs Pathways Activate eNOS in Response to EPA:DHA 6:1

    PubMed Central

    Zgheel, Faraj; Alhosin, Mahmoud; Rashid, Sherzad; Burban, Mélanie; Auger, Cyril; Schini-Kerth, Valérie B.

    2014-01-01

    Aims Omega-3 fatty acid products containing eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) have vasoprotective effects, in part, by stimulating the endothelial formation of nitric oxide (NO). This study determined the role of the EPA:DHA ratio and amount, and characterized the mechanism leading to endothelial NO synthase (eNOS) activation. Methods and Results EPA:DHA 6∶1 and 9∶1 caused significantly greater endothelium-dependent relaxations in porcine coronary artery rings than EPA:DHA 3∶1, 1∶1, 1∶3, 1∶6, 1∶9, EPA and DHA alone, and EPA:DHA 6∶1 with a reduced EPA + DHA amount, which were inhibited by an eNOS inhibitor. Relaxations to EPA:DHA 6∶1 were insensitive to cyclooxygenase inhibition, and reduced by inhibitors of either oxidative stress, Src kinase, PI3-kinase, p38 MAPK, MEK, or JNK. EPA:DHA 6∶1 induced phosphorylation of Src, Akt, p38 MAPK, ERK, JNK and eNOS; these effects were inhibited by MnTMPyP. EPA:DHA 6∶1 induced the endothelial formation of ROS in coronary artery sections as assessed by dihydroethidium, and of superoxide anions and hydrogen peroxide in cultured endothelial cells as assessed by electron spin resonance with the spin probe CMH, and the Amplex Red based assay, respectively. Conclusion Omega-3 fatty acids cause endothelium-dependent NO-mediated relaxations in coronary artery rings, which are dependent on the EPA:DHA ratio and amount, and involve an intracellular activation of the redox-sensitive PI3-kinase/Akt and MAPKs pathways to activate eNOS. PMID:25133540

  11. A2B adenosine receptor contributes to penile erection via PI3K/AKT signaling cascade-mediated eNOS activation

    PubMed Central

    Wen, Jiaming; Grenz, Almut; Zhang, Yujin; Dai, Yingbo; Kellems, Rodney E.; Blackburn, Michael R.; Eltzschig, Holger K.; Xia, Yang

    2011-01-01

    Normal penile erection is under the control of multiple factors and signaling pathways. Although adenosine signaling is implicated in normal and abnormal penile erection, the exact role and the underlying mechanism for adenosine signaling in penile physiology remain elusive. Here we report that shear stress leads to increased adenosine release from endothelial cells. Subsequently, we determined that ecto-5′-nucleotidase (CD73) is a key enzyme required for the production of elevated adenosine from ATP released by shear-stressed endothelial cells. Mechanistically, we demonstrate that shear stress-mediated elevated adenosine functions through the adenosine A2B receptor (A2BR) to activate the PI3K/AKT signaling cascade and subsequent increased endothelial nitric oxide synthase (eNOS) phosphorylation. These in vitro studies led us to discover further that adenosine was induced during sustained penile erection and contributes to PI3K/AKT activation and subsequent eNOS phosphorylation via A2BR signaling in intact animal. Finally, we demonstrate that lowering adenosine in wild-type mice or genetic deletion of A2BR in mutant mice significantly attenuated PI3K/AKT activation, eNOS phosphorylation, and subsequent impaired penile erection featured with the reduction of ratio of maximal intracavernosal pressure to systemic arterial pressure from 0.49 ± 0.03 to 0.41 ± 0.05 and 0.38 ± 0.04, respectively (both P<0.05). Overall, using biochemical, cellular, genetic, and physiological approaches, our findings reveal that adenosine is a novel molecule signaling via A2BR activation, contributing to penile erection via PI3K/AKT-dependent eNOS activation. These studies suggest that this signaling pathway may be a novel therapeutic target for erectile disorders.—Wen, J., Grenz, A., Zhang, Y., Dai, Y., Kellems, R. E., Blackburn, M. R., Eltzschig, H. K., Xia, Y. A2B adenosine receptor contributes to penile erection via PI3K/AKT signaling cascade-mediated eNOS activation. PMID

  12. MiR-21 is induced in endothelial cells by shear stress and modulates apoptosis and eNOS activity

    SciTech Connect

    Weber, Martina; Baker, Meredith B.; Moore, Jeffrey P.; Searles, Charles D.

    2010-03-19

    Mechanical forces associated with blood flow play an important role in regulating vascular signaling and gene expression in endothelial cells (ECs). MicroRNAs (miRNAs) are a class of noncoding RNAs that posttranscriptionally regulate the expression of genes involved in diverse cell functions, including differentiation, growth, proliferation, and apoptosis. miRNAs are known to have an important role in modulating EC biology, but their expression and functions in cells subjected to shear stress conditions are unknown. We sought to determine the miRNA expression profile in human ECs subjected to unidirectional shear stress and define the role of miR-21 in shear stress-induced changes in EC function. TLDA array and qRT-PCR analysis performed on HUVECs exposed to prolonged unidirectional shear stress (USS, 24 h, 15 dynes/cm{sup 2}) identified 13 miRNAs whose expression was significantly upregulated (p < 0.05). The miRNA with the greatest change was miR-21; it was increased 5.2-fold (p = 0.002) in USS-treated versus control cells. Western analysis demonstrated that PTEN, a known target of miR-21, was downregulated in HUVECs exposed to USS or transfected with pre-miR-21. Importantly, HUVECs overexpressing miR-21 had decreased apoptosis and increased eNOS phosphorylation and nitric oxide (NO{sup {center_dot}}) production. These data demonstrate that shear stress forces regulate the expression of miRNAs in ECs, and that miR-21 influences endothelial biology by decreasing apoptosis and activating the NO{sup {center_dot}} pathway. These studies advance our understanding of the mechanisms by which shear stress forces modulate vascular homeostasis.

  13. PI3K/AKT signaling pathway plays a role in enhancement of eNOS activity by recombinant human angiotensin converting enzyme 2 in human umbilical vein endothelial cells

    PubMed Central

    Zhang, Yan; Wang, Shi-Jie; Han, Zhen-Hua; Li, Yong-Qin; Xue, Jia-Hong; Gao, Deng-Feng; Wu, Xiao-San; Wang, Cong-Xia

    2014-01-01

    The aim of this study was to investigate the effect of PI3K/AKT signaling pathway in the activity of recombinant human angiotensin converting enzyme 2 (rhACE2) promoted the activity of endothelial nitric oxide synthase (eNOS). The human umbilical vein endothelial cells (HUVEC) were cultured in vitro. Then treated with Ang II (1×10-6 mol/L) for 24 h. The rhACE2 (100 μmol/L) was added and incubated for 5, 10, 15, 30, 60 min respectively which was based on Ang II intervention. The effect of rhACE2 on phosphorylation eNOS level was also observed in the presence of LY294002 (10 μmol/L) (PI3K/AKT inhibitors). Griess reagent method was applied to measure NO contents in cell culture supernatant, RT-PCR to detect the expression of eNOSmRNA in HUVEC, and Western blot to detect the expression of eNOS and phosphorylated eNOS. In Ang II intervention group, NO contents were significantly lower than control group (P < 0.05). Through rhACE2 treatment, the NO contents in cell culture medium and the expression level of phosphorylated eNOS were significantly higher than in Ang II intervention group (P < 0.05), but eNOSmRNA and non-phosphorylated eNOS protein expression level showed no significant difference (P > 0.05). After HUVEC was intervened by PI3K/AKT pathway inhibitor LY294002, the expression level of phosphorylated eNOS was significantly lower than that in the rhACE2 30 min treatment group (P < 0.05). rhACE2 may reduce the activity of Ang II inhibited endothelial cell eNOS, which can be blocked by PI3K/AKT pathway inhibitor LY294002, suggesting PI3K/AKT signaling pathway plays an important role in rhACE2’s promotion of the activity of endothelial cell eNOS. PMID:25550859

  14. Endogenous growth of persistently active volcanoes

    NASA Astrophysics Data System (ADS)

    Francis, Peter; Oppenheimer, Clive; Stevenson, David

    1993-12-01

    LAVA lakes and active strombolian vents have persisted at some volcanoes for periods exceeding the historic record. They liberate prodigious amounts of volatiles and thermal energy but erupt little lava, a paradox that raises questions about how volcanoes grow. Although long-lasting surface manifestations can be sustained by convective exchange of magma with deeper reservoirs, residence times of magmas beneath several basaltic volcanoes are & sim10-100 years1,2, indicating that where surface activity continues for more than 100-1,000 years, the reservoirs are replenished by new magma. Endogenous growth of Kilauea volcano (Hawaii) through dyke intrusion and cumulate formation is a well-understood consequence of the steady supply of mantle-derived magma3,4. As we show here, inferred heat losses from the Halemaumau lava lake indicate a period of dominantly endogenous growth of Kilauea volcano during the nineteenth century. Moreover, heat losses and degassing rates for several other volcanoes, including Stromboli, also indicate cryptic influxes of magma that far exceed visible effluxes of lavas. We propose that persistent activity at Stromboli, and at other volcanoes in different tectonic settings, is evidence of endogenous growth, involving processes similar to those at Kilauea.

  15. Resonant activation: a strategy against bacterial persistence

    NASA Astrophysics Data System (ADS)

    Fu, Yan; Zhu, Meng; Xing, Jianhua

    2010-03-01

    A bacterial colony may develop a small number of cells genetically identical to, but phenotypically different from, other normally growing bacteria. These so-called persister cells keep themselves in a dormant state and thus are insensitive to antibiotic treatment, resulting in serious problems of drug resistance. In this paper, we proposed a novel strategy to 'kill' persister cells by triggering them to switch, in a fast and synchronized way, into normally growing cells that are susceptible to antibiotics. The strategy is based on resonant activation (RA), a well-studied phenomenon in physics where the internal noise of a system can constructively facilitate fast and synchronized barrier crossings. Through stochastic Gilliespie simulation with a generic toggle switch model, we demonstrated that RA exists in the phenotypic switching of a single bacterium. Further, by coupling single cell level and population level simulations, we showed that with RA, one can greatly reduce the time and total amount of antibiotics needed to sterilize a bacterial population. We suggest that resonant activation is a general phenomenon in phenotypic transition, and can find other applications such as cancer therapy.

  16. Extract from Ribes nigrum leaves in vitro activates nitric oxide synthase (eNOS) and increases CD39 expression in human endothelial cells.

    PubMed

    Luzak, Boguslawa; Boncler, Magdalena; Rywaniak, Joanna; Dudzinska, Dominika; Rozalski, Marek; Krajewska, Urszula; Balcerczak, Ewa; Podsedek, Anna; Redzynia, Malgorzata; Watala, Cezary

    2014-12-01

    The aim of the present study was to evaluate whether blackcurrant leaf extract (BLE) modulates endothelium antithrombotic function, namely increases the expression/activity of ADPase (CD39) and augments the production of nitric oxide in human umbilical vein endothelial cells (HUVEC). It was found that BLE with proanthocyanidins (60 % of the total polyphenol content) increased the CD39-positive endothelial cell fraction (up to 10 % for 2.5 μg/ml, and up to 33 % for 15 μg/ml, p < 0.05 or less) in a concentration-dependent manner, and enhanced endothelial nitric oxide synthase (eNOS) activation (T495 phosphorylation decreased by 31 ± 6 % for 2.5 μg/ml and 48 ± 6 % for 15 μg/ml; S1177 phosphorylation increased by 13 ± 3 % for 2.5 μg/ml and 18 ± 7 % for 15 μg/ml, compared to untreated cells, p < 0.05 or less). Additionally, incubation for 24 or 48 h with BLE at a lower range of polyphenol concentrations, significantly increased cell viability with a maximal effect at 2.5 μg/ml (viability increased by 24.8 ± 1.0 % for 24 h and by 32.5 ± 2.7 % for 48-h time incubation, p < 0.0001). The increased CD39 expression and the increased eNOS activation in HUVEC can be regarded as the beneficial markers of the improvement of antiplatelet action of endothelial cells. Unexpectedly, these assumptions were not confirmed in the experimental model of platelet-endothelial cell interactions. These observations lead to the conclusion that BLE may improve endothelial cell viability at low physiological concentrations without affecting the antiplatelet action of endothelium. PMID:25407137

  17. Long-term persistence of solar activity

    NASA Technical Reports Server (NTRS)

    Ruzmaikin, Alexander; Feynman, Joan; Robinson, Paul

    1994-01-01

    We examine the question of whether or not the non-periodic variations in solar activity are caused by a white-noise, random process. The Hurst exponent, which characterizes the persistence of a time series, is evaluated for the series of C-14 data for the time interval from about 6000 BC to 1950 AD. We find a constant Hurst exponent, suggesting that solar activity in the frequency range from 100 to 3000 years includes an important continuum component in addition to the well-known periodic variations. The value we calculate, H approximately 0.8, is significantly larger than the value of 0.5 that would correspond to variations produced by a white-noise process. This value is in good agreement with the results for the monthly sunspot data reported elsewhere, indicating that the physics that produces the continuum is a correlated random process and that it is the same type of process over a wide range of time interval lengths.

  18. Persistent neural activity in head direction cells

    NASA Technical Reports Server (NTRS)

    Taube, Jeffrey S.; Bassett, Joshua P.; Oman, C. M. (Principal Investigator)

    2003-01-01

    Many neurons throughout the rat limbic system discharge in relation to the animal's directional heading with respect to its environment. These so-called head direction (HD) cells exhibit characteristics of persistent neural activity. This article summarizes where HD cells are found, their major properties, and some of the important experiments that have been conducted to elucidate how this signal is generated. The number of HD and angular head velocity cells was estimated for several brain areas involved in the generation of the HD signal, including the postsubiculum, anterior dorsal thalamus, lateral mammillary nuclei and dorsal tegmental nucleus. The HD cell signal has many features in common with what is known about how neural integration is accomplished in the oculomotor system. The nature of the HD cell signal makes it an attractive candidate for using neural network models to elucidate the signal's underlying mechanisms. The conditions that any network model must satisfy in order to accurately represent how the nervous system generates this signal are highlighted and areas where key information is missing are discussed.

  19. Brain calculus: neural integration and persistent activity.

    PubMed

    McCormick, D A

    2001-02-01

    Tank and colleagues make in vivo cellular recordings from neurons in a "neural integrator" of the goldfish involved in maintaining eye position. In this circuit, "working" memory may be the result of persistent changes in the state of the local network.

  20. BET Bromodomain Suppression Inhibits VEGF-induced Angiogenesis and Vascular Permeability by Blocking VEGFR2-mediated Activation of PAK1 and eNOS.

    PubMed

    Huang, Mingcheng; Qiu, Qian; Xiao, Youjun; Zeng, Shan; Zhan, Mingying; Shi, Maohua; Zou, Yaoyao; Ye, Yujin; Liang, Liuqin; Yang, Xiuyan; Xu, Hanshi

    2016-01-01

    The tyrosine kinase receptor vascular endothelial growth factor receptor 2 (VEGFR2) is a critical modulator of angiogenesis. Increasing evidence indicate the important role of bromodomain and extra-terminal domain (BET) of chromatin adaptors in regulating tumor growth and inflammatory response. However, whether BET proteins have a role in angiogenesis and endothelial permeability is unclear. In this study, we observed that treatment with JQ1, a specific BET inhibitor, suppressed in vitro tube formation of human umbilical vein endothelial cells (HUVECs) and in vivo angiogenesis in a Matrigel plug and oxygen-induced retinopathy neovascularization. JQ1 attenuated the VEGF-induced decrease in TEER in HUVECs and prevented Evans blue dye leakage in the VEGF-induced Miles assay in athymic Balb/c nude mice. BET inhibition with JQ1 or shRNA for Brd2 or Brd4 suppressed VEGF-induced migration, proliferation, and stress fiber formation of HUVECs. Furthermore, BET inhibition suppressed phosphorylation of VEGFR2 and PAK1, as well as eNOS activation in VEGF-stimulated HUVECs. Inhibition with VEGFR2 and PAK1 also reduced migration and proliferation, and attenuated the VEGF-induced decrease in TEER. Thus, our observations suggest the important role of BET bromodomain in regulating VEGF-induced angiogenesis. Strategies that target the BET bromodomain may provide a new therapeutic approach for angiogenesis-related diseases. PMID:27044328

  1. BET Bromodomain Suppression Inhibits VEGF-induced Angiogenesis and Vascular Permeability by Blocking VEGFR2-mediated Activation of PAK1 and eNOS

    PubMed Central

    Huang, Mingcheng; Qiu, Qian; Xiao, Youjun; Zeng, Shan; Zhan, Mingying; Shi, Maohua; Zou, Yaoyao; Ye, Yujin; Liang, Liuqin; Yang, Xiuyan; Xu, Hanshi

    2016-01-01

    The tyrosine kinase receptor vascular endothelial growth factor receptor 2 (VEGFR2) is a critical modulator of angiogenesis. Increasing evidence indicate the important role of bromodomain and extra-terminal domain (BET) of chromatin adaptors in regulating tumor growth and inflammatory response. However, whether BET proteins have a role in angiogenesis and endothelial permeability is unclear. In this study, we observed that treatment with JQ1, a specific BET inhibitor, suppressed in vitro tube formation of human umbilical vein endothelial cells (HUVECs) and in vivo angiogenesis in a Matrigel plug and oxygen-induced retinopathy neovascularization. JQ1 attenuated the VEGF-induced decrease in TEER in HUVECs and prevented Evans blue dye leakage in the VEGF-induced Miles assay in athymic Balb/c nude mice. BET inhibition with JQ1 or shRNA for Brd2 or Brd4 suppressed VEGF-induced migration, proliferation, and stress fiber formation of HUVECs. Furthermore, BET inhibition suppressed phosphorylation of VEGFR2 and PAK1, as well as eNOS activation in VEGF-stimulated HUVECs. Inhibition with VEGFR2 and PAK1 also reduced migration and proliferation, and attenuated the VEGF-induced decrease in TEER. Thus, our observations suggest the important role of BET bromodomain in regulating VEGF-induced angiogenesis. Strategies that target the BET bromodomain may provide a new therapeutic approach for angiogenesis-related diseases. PMID:27044328

  2. Persistent Focal Behavior and Physical Activity Performance

    ERIC Educational Resources Information Center

    Erfle, Stephen E.

    2014-01-01

    This article examines the proclivity and performance attributes of focal students across time and activities using data from 9,345 students. Three systematic focal behavior partitions are examined: Across activities, across time, and across activities and time. A student's performance is focal if it ends in 0 or 5 for push-ups and 0 for…

  3. Disturbance effects of PM₁₀ on iNOS and eNOS mRNA expression levels and antioxidant activity induced by ischemia-reperfusion injury in isolated rat heart: protective role of vanillic acid.

    PubMed

    Dianat, Mahin; Radmanesh, Esmat; Badavi, Mohammad; Mard, Seyed Ali; Goudarzi, Gholamraza

    2016-03-01

    Myocardial infarction is the acute condition of myocardial necrosis that occurs as a result of imbalance between coronary blood supply and myocardial demand. Air pollution increases the risk of death from cardiovascular diseases (CVDs). The aim of this study was to investigate the effects of particulate matter (PM) on oxidative stress, the expression of inducible nitric oxide synthase (iNOS) and endothelial nitric oxide synthase (eNOS) messenger RNA (mRNA) level induced by ischemia-reperfusion injury, and the protective effects of vanillic acid (VA) in the isolated rat heart. Male Wistar rats were randomly divided into eight groups (n = 10), namely control, VAc, sham, VA, PMa (0.5 mg/kg), PMb (2.5 mg/kg), PMc (5 mg/kg), and PMc + VA groups. Particles with an aerodynamic diameter <10 μm (PM10) was instilled into the trachea through a fine intubation tube. Two days following the PM10 instillation, the animal's hearts were isolated and transferred to a Langendorff apparatus. The hearts were subjected to 30 min of global ischemia followed by 60 min of reperfusion. The activities of superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT), xanthine oxidase (XOX), and lactate dehydrogenase (LDH) were measured using special kits. Reverse transcription polymerase chain reaction (RT-PCR) was used to determine levels of iNOS and eNOS mRNA. An increase in left ventricular end-diastolic pressure (LVEDP), S-T elevation, and oxidative stress in PM10 groups was observed. Ischemia-reperfusion (I/R) induction showed a significant augment in the expression of iNOS mRNA level and a significant decrease in the expression eNOS mRNA level. This effect was more pronounced in the PM groups than in the control and sham groups. Vanillic acid caused a significant decrease in LVEDP, S-T elevation, and also a significant difference in eNOS mRNA expression level, antioxidant enzymes, iNOS mRNA expression level, and oxidative stress occurred on myocardial dysfunction

  4. Persistent Aeolian Activity at Endeavour Crater, Mars

    NASA Astrophysics Data System (ADS)

    Chojnacki, M.; Michaels, T. I.; Fenton, L. K.

    2013-12-01

    Long-term monitoring of sites that are known to have active dunes and ripples is generally limited to 3 Mars-Years (MY). Here, we discuss new results of dune activity and albedo change in Endeavour crater (EC), Meridiani Planum (MP) that record eight MY of aeolian activity. MP dune fields often show large yearly variations in albedo; EC darkened by ~12% in TES albedo between MY 24 and 26 (from 0.14 to 0.12). THEMIS VIS albedo of dunes did not change significantly from MY 26 to 29, but did decrease notably (~15 %) in MY 30. These darkening events are most likely related to aeolian-driven dust cleaning (e.g., removal by saltating sand, dust devils). For example, the Opportunity rover (poised on the western rim of EC) observed evidence for a MY 31 dune field dust-clearing event. HiRISE monitoring of MP has shown it be one of the most active regions outside of north polar latitudes. Paired images of western EC taken 3 MY apart show clear evidence for dune modification that include: ripple migration, change in dune perimeters, exposure of previously buried light-toned rock, and/or burial of rock by sand (Fig. 1a-1b). Dune slip face movement is evident for most dunes, where crests and aprons advanced (2-7 m) in the downwind direction (to the SSE) at rates of 0.7-2.3 m per MY. Small dome dunes in the eastern EC were found to have a large degree of aeolian activity (e.g., deflation and/or translation) by an earlier study that used MGS-MRO images (MY 24-30). New MY 31 images validate earlier observations, showing clear evidence for bedform deflation where dunes often occupy less area (~50%) than in earlier MY 29 images (Fig. 1c-1d). Areal removal rates are on par with earlier estimates. Bedform modification and sand streamer orientation appear to be caused by a NNW wind regime, consistent with earlier observations, mesoscale modeling, and the transport direction of barchans to the west. Dunes in EC are now known to be periodically (consistently?) active from over a decade

  5. Persulfate persistence under thermal activation conditions.

    PubMed

    Johnson, Richard L; Tratnyek, Paul G; Johnson, Reid O'Brien

    2008-12-15

    Contaminant destruction with in situ chemical oxidation (ISCO) using persulfate (peroxydisulfate, S2O8(2-)) can be enhanced by activation, which increases the rate of persulfate decomposition to sulfate radicals (SO4*-). This step initiates a chain of radical reactions involving species (including SO4*- and OH*) that oxidize contaminants more rapidly than persulfate does directly. Among current activation methods, thermal activation is the least well studied. Combining new data for environmentally relevant conditions with previously published data, we have computed three sets of Arrhenius parameters (In A and Eact) that describe the rate of persulfate decomposition in homogeneous solutions over a wide range of temperature and pH. The addition of soil increases the decomposition rate of persulfate due to reactions with organic matter and possibly mineral surfaces, but the kinetics are still pseudo-first-order in persulfate and conform to the Arrhenius model. A series of respike experiments with soil at 70 degrees C demonstrate that once the oxidant demand is met, reaction rates return to values near those observed in the homogeneous solution case. However, even after the oxidant demand is met, the relatively short lifetime of the persulfate at elevated temperatures (e.g., >50 degrees C) will limit the delivery time over which persulfate can be effective. PMID:19174915

  6. Antiepileptic Activity of Preferential Inhibitors of Persistent Sodium Current

    PubMed Central

    Anderson, Lyndsey L.; Thompson, Christopher H.; Hawkins, Nicole A.; Nath, Ravi D.; Petersohn, Adam A.; Rajamani, Sridharan; Bush, William S.; Frankel, Wayne N.; Vanoye, Carlos G.; Kearney, Jennifer A.; George, Alfred L.

    2014-01-01

    Objective Evidence from basic neurophysiology and molecular genetics has implicated persistent sodium current conducted by voltage-gated sodium (NaV) channels as a contributor to the pathogenesis of epilepsy. Many antiepileptic drugs target NaV channels and modulate neuronal excitability mainly by a use-dependent block of transient sodium current, although suppression of persistent current may also contribute to the efficacy of these drugs. We hypothesized that a drug or compound capable of preferential inhibition of persistent sodium current would have antiepileptic activity. Methods We examined the antiepileptic activity of two selective persistent sodium current blockers ranolazine, an FDA-approved drug for treatment of angina pectoris, and GS967, a novel compound with more potent effects on persistent current, in the epileptic Scn2aQ54 mouse model. We also examined the effect of GS967 in the maximal electroshock model and evaluated effects of the compound on neuronal excitability, propensity for hilar neuron loss, development of mossy fiber sprouting and survival of Scn2aQ54 mice. Results We found that ranolazine was capable of reducing seizure frequency by ~50% in Scn2aQ54 mice. The more potent persistent current blocker GS967 reduced seizure frequency by greater than 90% in Scn2aQ54 mice and protected against induced seizures in the maximal electroshock model. GS967 greatly attenuated abnormal spontaneous action potential firing in pyramidal neurons acutely isolated from Scn2aQ54 mice. In addition to seizure suppression in vivo, GS967 treatment greatly improved the survival of Scn2aQ54 mice, prevented hilar neuron loss, and suppressed the development of hippocampal mossy fiber sprouting. Significance Our findings indicate that the selective persistent sodium current blocker GS967 has potent antiepileptic activity and this compound could inform development of new agents. PMID:24862204

  7. Role of Prefrontal Persistent Activity in Working Memory

    PubMed Central

    Riley, Mitchell R.; Constantinidis, Christos

    2016-01-01

    The prefrontal cortex is activated during working memory, as evidenced by fMRI results in human studies and neurophysiological recordings in animal models. Persistent activity during the delay period of working memory tasks, after the offset of stimuli that subjects are required to remember, has traditionally been thought of as the neural correlate of working memory. In the last few years several findings have cast doubt on the role of this activity. By some accounts, activity in other brain areas, such as the primary visual and posterior parietal cortex, is a better predictor of information maintained in visual working memory and working memory performance; dynamic patterns of activity may convey information without requiring persistent activity at all; and prefrontal neurons may be ill-suited to represent non-spatial information about the features and identity of remembered stimuli. Alternative interpretations about the role of the prefrontal cortex have thus been suggested, such as that it provides a top-down control of information represented in other brain areas, rather than maintaining a working memory trace itself. Here we review evidence for and against the role of prefrontal persistent activity, with a focus on visual neurophysiology. We show that persistent activity predicts behavioral parameters precisely in working memory tasks. We illustrate that prefrontal cortex represents features of stimuli other than their spatial location, and that this information is largely absent from early cortical areas during working memory. We examine memory models not dependent on persistent activity, and conclude that each of those models could mediate only a limited range of memory-dependent behaviors. We review activity decoded from brain areas other than the prefrontal cortex during working memory and demonstrate that these areas alone cannot mediate working memory maintenance, particularly in the presence of distractors. We finally discuss the discrepancy between

  8. MicroRNA-27b plays a role in pulmonary arterial hypertension by modulating peroxisome proliferator-activated receptor γ dependent Hsp90-eNOS signaling and nitric oxide production

    SciTech Connect

    Bi, Rui; Bao, Chunrong; Jiang, Lianyong; Liu, Hao; Yang, Yang; Mei, Ju; Ding, Fangbao

    2015-05-01

    Pulmonary artery endothelial dysfunction is associated with pulmonary arterial hypertension (PAH). Based on recent studies showing that microRNA (miR)-27b is aberrantly expressed in PAH, we hypothesized that miR-27b may contribute to pulmonary endothelial dysfunction and vascular remodeling in PAH. The effect of miR-27b on pulmonary endothelial dysfunction and the underlying mechanism were investigated in human pulmonary artery endothelial cells (HPAECs) in vitro and in a monocrotaline (MCT)-induced model of PAH in vivo. miR-27b expression was upregulated in MCT-induced PAH and inversely correlated with the levels of peroxisome proliferator-activated receptor (PPAR)-γ, and miR-27b inhibition attenuated MCT-induced endothelial dysfunction and remodeling and prevented PAH associated right ventricular hypertrophy and systolic pressure in rats. PPARγ was confirmed as a direct target of miR-27b in HPAECs and shown to mediate the effect of miR-27b on the disruption of endothelial nitric oxide synthase (eNOS) coupling to Hsp90 and the suppression of NO production associated with the PAH phenotype. We showed that miR-27b plays a role endothelial function and NO release and elucidated a potential mechanism by which miR-27b regulates Hsp90-eNOS and NO signaling by modulating PPARγ expression, providing potential therapeutic targets for the treatment of PAH. - Highlights: • miR-27b plays a role in endothelial function and NO release. • miR-27b inhibition ameliorates MCT-induced endothelial dysfunction and PAH. • miR-27b targets PPARγ in HPAECs. • miR-27b regulates PPARγ dependent Hsp90-eNOS and NO signaling.

  9. Reversal of SIN-1-induced eNOS dysfunction by the spin trap, DMPO, in bovine aortic endothelial cells via eNOS phosphorylation

    PubMed Central

    Das, Amlan; Gopalakrishnan, Bhavani; Druhan, Lawrence J; Wang, Tse-Yao; De Pascali, Francesco; Rockenbauer, Antal; Racoma, Ira; Varadharaj, Saradhadevi; Zweier, Jay L; Cardounel, Arturo J; Villamena, Frederick A

    2014-01-01

    Background and Purpose Nitric oxide (NO) derived from eNOS is mostly responsible for the maintenance of vascular homeostasis and its decreased bioavailability is characteristic of reactive oxygen species (ROS)-induced endothelial dysfunction (ED). Because 5,5-dimethyl-1-pyrroline-N-oxide (DMPO), a commonly used spin trap, can control intracellular nitroso-redox balance by scavenging ROS and donating NO, it was employed as a cardioprotective agent against ED but the mechanism of its protection is still not clear. This study elucidated the mechanism of protection by DMPO against SIN-1-induced oxidative injury to bovine aortic endothelial cells (BAEC). Experimental Approach BAEC were treated with SIN-1, as a source of peroxynitrite anion (ONOO−), and then incubated with DMPO. Cytotoxicity following SIN-1 alone and cytoprotection by adding DMPO was assessed by MTT assay. Levels of ROS and NO generation from HEK293 cells transfected with wild-type and mutant eNOS cDNAs, tetrahydrobiopterin bioavailability, eNOS activity, eNOS and Akt kinase phosphorylation were measured. Key Results Post-treatment of cells with DMPO attenuated SIN-1-mediated cytotoxicity and ROS generation, restoration of NO levels via increased in eNOS activity and phospho-eNOS levels. Treatment with DMPO alone significantly increased NO levels and induced phosphorylation of eNOS Ser1179 via Akt kinase. Transfection studies with wild-type and mutant human eNOS confirmed the dual role of eNOS as a producer of superoxide anion (O2−) with SIN-1 treatment, and a producer of NO in the presence of DMPO. Conclusion and Implications Post-treatment with DMPO of oxidatively challenged cells reversed eNOS dysfunction and could have pharmacological implications in the treatment of cardiovascular diseases. PMID:24405159

  10. A Clinical Drug Library Screen Identifies Tosufloxacin as Being Highly Active against Staphylococcus aureus Persisters

    PubMed Central

    Niu, Hongxia; Cui, Peng; Yee, Rebecca; Shi, Wanliang; Zhang, Shuo; Feng, Jie; Sullivan, David; Zhang, Wenhong; Zhu, Bingdong; Zhang, Ying

    2015-01-01

    To identify effective compounds that are active against Staphylococcus aureus (S. aureus) persisters, we screened a clinical drug library consisting of 1524 compounds and identified six drug candidates that had anti-persister activity: tosufloxacin, clinafloxacin, sarafloxacin, doxycycline, thiostrepton, and chlorosalicylanilide. Among them, tosufloxacin had the highest anti-persister activity, which could completely eradicate S. aureus persisters within 2 days in vitro. Clinafloxacin ranked the second with very few persisters surviving the drug exposure. Interestingly, we found that both tosufloxacin and trovafloxacin that had high activity against persisters contained at the N-1 position the 2,4-difluorophenyl group, which is absent in other less active quinolones and may be associated with the high anti-persister activity. Further studies are needed to evaluate tosufloxacin in animal models and to explain its unique activity against bacterial persisters. Our findings may have implications for improved treatment of persistent bacterial infections. PMID:27025627

  11. Prunella vulgaris L. Upregulates eNOS expression in human endothelial cells.

    PubMed

    Xia, Ning; Bollinger, Larissa; Steinkamp-Fenske, Katja; Förstermann, Ulrich; Li, Huige

    2010-01-01

    The purported effects of "circulation-improving" herbs used in traditional Chinese medicine (TCM) show striking similarities with the vascular actions of nitric oxide (NO) produced by the endothelial NO synthase (eNOS). We have previously reported that Salviae miltiorrhizae radix and Zizyphi spinosae semen upregulate eNOS expression. In the present study, we studied the effect on eNOS gene expression of 15 Chinese herbs with potential effects on the vasculature, and identified Prunella vulgaris L. (PVL) (flowering spike) as a potent eNOS-upregulating agent. In EA.hy 926 cells, a cell line derived from human umbilical vein endothelial cells (HUVEC), an aqueous extract of PVL increased eNOS promoter activity, eNOS mRNA and protein expressions, as well as NO production in concentration- and time-dependent manners. We have previously shown that ursolic acid (a constituent of Salviae miltiorrhizae radix), betulinic acid (a compound present in Zizyphi spinosae semen), luteolin and cynaroside (ingredients of artichoke, Cynara scolymus L.) are capable of enhancing eNOS gene expression. These compounds are also present in significant quantities in PVL. Thus, PVL contains active principles that stimulate human eNOS gene expression, and such compounds may have therapeutic potential against cardiovascular diseases. PMID:20503475

  12. Active rejection of persistent disturbances in flexible space structures

    NASA Technical Reports Server (NTRS)

    Hwang, Cheng-Neng; Jayasuriya, Suhada; Parlos, Alexander G.; Sunkel, John W.

    1990-01-01

    A dynamic compensator for active rejection of persistent disturbances in flexible space structures is designed on the principle of the H(infinity)-optimization of the sensitivity transfer function matrix. A general state space solution is formulated to the multiinput multioutput H(infinity)-optimal control problem, allowing the use of the H(infinity)-optimal synthesis algorithm for the state-space models of space structures that result from model order reduction. Disturbances encountered in flexible space structures, such as shuttle docking, are investigated using the high-mode and the reduced-order models of a cantilevered two-bay truss, demonstrating the applicability of the H(infinity)-optimal approach.

  13. Persistence of high intestinal lactase activity in Pakistan.

    PubMed

    Abbas, H; Ahmad, M

    1983-01-01

    In order to determine the incidence of persistence of high intestinal lactase activity (PLA) in a Pakistani human population, 53 probands belonging to the Punjabi ethnic group were examined using a lactose tolerance test. The incidence of PLA in the sample was found to be 55%, which has been compared with the incidence in other ethnic groups racially or geographically related to the Pakistani population. Various possible explanations for the fairly high incidence of PLA in the Punjabi ethnic group have been discussed. PMID:6885071

  14. C. pneumoniae disrupts eNOS trafficking and impairs NO production in human aortic endothelial cells.

    PubMed

    Mueller, Konrad E; Wolf, Katerina

    2015-01-01

    Endothelial nitric oxide synthase (eNOS) generated NO plays a crucial physiological role in the regulation of vascular tone. eNOS is a constitutively expressed synthase whose enzymatic function is regulated by dual acylation, phosphorylation, protein-protein interaction and subcellular localization. In endothelial cells, the enzyme is primarily localized to the Golgi apparatus (GA) and the plasma membrane where it binds to caveolin-1. Upon stimulation, the enzyme is translocated from the plasma membrane to the cytoplasm where it generates NO. When activation of eNOS ceases, the majority of the enzyme is recycled back to the membrane fraction. An inability of eNOS to cycle between the cytosol and the membrane leads to impaired NO production and vascular dysfunction. Chlamydia pneumoniae is a Gram-negative obligate intracellular bacterium that primarily infects epithelial cells of the human respiratory tract, but unlike any other chlamydial species, C. pneumoniae displays tropism toward atherosclerotic tissues. In this study, we demonstrate that C. pneumoniae inclusions colocalize with eNOS, and the microorganism interferes with trafficking of the enzyme from the GA to the plasma membrane in primary human aortic endothelial cells. This mislocation of eNOS results in significant inhibition of NO release by C. pneumoniae-infected cells. Furthermore, we show that the distribution of eNOS in C. pneumoniae-infected cells is altered due to an intimate association of the Golgi complex with chlamydial inclusions rather than by direct interaction of the enzyme with the chlamydial inclusion membrane.

  15. Long-term persistence of solar activity. [Abstract only

    NASA Technical Reports Server (NTRS)

    Ruzmaikin, Alexander; Feynman, Joan; Robinson, Paul

    1994-01-01

    The solar irradiance has been found to change by 0.1% over the recent solar cycle. A change of irradiance of about 0.5% is required to effect the Earth's climate. How frequently can a variation of this size be expected? We examine the question of the persistence of non-periodic variations in solar activity. The Huerst exponent, which characterizes the persistence of a time series (Mandelbrot and Wallis, 1969), is evaluated for the series of C-14 data for the time interval from about 6000 BC to 1950 AD (Stuiver and Pearson, 1986). We find a constant Huerst exponent, suggesting that solar activity in the frequency range of from 100 to 3000 years includes an important continuum component in addition to the well-known periodic variations. The value we calculate, H approximately equal to 0.8, is significantly larger than the value of 0.5 that would correspond to variations produced by a white-noise process. This value is in good agreement with the results for the monthly sunspot data reported elsewhere, indicating that the physics that produces the continuum is a correlated random process (Ruzmaikin et al., 1992), and that is is the same type of process over a wide range of time interval lengths. We conclude that the time period over which an irradiance change of 0.5% can be expected to occur is significantly shorter than that which would be expected for variations produced by a white-noise process.

  16. Persistence of high intestinal lactase activity (lactose tolerance) in Afghanistan.

    PubMed

    Rahimi, A G; Delbrück, H; Haeckel, R; Goedde, H W; Flatz, G

    1976-09-10

    Two hundred and seventy apparently healthy adult subjects from Afghanistan, mainly from the central and eastern parts of the country, were subjected to a lactose tolerance test. The change of blood glucose from the fasting concentration at 20 min after the administration of lactose showed a bimodal distribution. Forty-seven subjects had a rise of blood glucose concentration of more than 1.1 mmol/l and were classified as persistence of high intestinal lactase activity (PHILA), a term which lays emphasis on the fact that high lactase activity in the adult is an unusual state whose prevalence in some populations requires explanation. In the Afghan sample there were no significant differences of the frequency of PHILA in different ethnic groups. PMID:965005

  17. A comparison of ENO and TVD schemes

    NASA Technical Reports Server (NTRS)

    Chang, Shih-Hung; Liou, Meng-Sing

    1988-01-01

    The numerical performance of a second-order upwind-based TVD scheme is compared with that of a uniform second-order ENO scheme on shock capturing. The cases considered include flows with Mach numbers of 2.9, 5.0, and 10.0. For cases with Mach numbers of 5.0 and 10.0, the computed ENO results are inferior to the corresponding TVD results.

  18. Effect of Learning Activity on Students' Motivation, Physical Activity Levels and Effort/Persistence

    ERIC Educational Resources Information Center

    Gao, Zan; Lee, Amelia M.; Xiang, Ping; Kosma, Maria

    2011-01-01

    The type of learning activity offered in physical education may influence students' motivational beliefs, physical activity participation and effort/persistence in class. However, most empirical studies have focused on the individual level rather than on the learner-content interactions. Accordingly, the potential effects of learning activities on…

  19. The role of eNOS phosphorylation in causing drug-induced vascular injury.

    PubMed

    Tobin, Grainne A McMahon; Zhang, Jun; Goodwin, David; Stewart, Sharron; Xu, Lin; Knapton, Alan; González, Carlos; Bancos, Simona; Zhang, Leshuai; Lawton, Michael P; Enerson, Bradley E; Weaver, James L

    2014-06-01

    Previously we found that regulation of eNOS is an important part of the pathogenic process of Drug-induced vascular injury (DIVI) for PDE4i. The aims of the current study were to examine the phosphorylation of eNOS in mesentery versus aorta at known regulatory sites across DIVI-inducing drug classes and to compare changes across species. We found that phosphorylation at S615 in rats was elevated 35-fold 2 hr after the last dose of CI-1044 in mesentery versus 3-fold in aorta. Immunoprecipitation studies revealed that many of the upstream regulators of eNOS activation were associated with eNOS in 1 or more signalosome complexes. Next rats were treated with drugs from 4 other classes known to cause DIVI. Each drug was given alone and in combination with SIN-1 (NO donor) or L-NAME (eNOS inhibitor), and the level of eNOS phosphorylation in mesentery and aorta tissue was correlated with the extent of vascular injury and measured serum nitrite. Drugs or combinations produced altered serum nitrite levels as well as vascular injury score in the mesentery. The results suggested that phosphorylation of S615 may be associated with DIVI activity. Studies with the species-specific A2A adenosine agonist CI-947 in rats versus primates showed a similar pattern.

  20. Synaptic scaling stabilizes persistent activity driven by asynchronous neurotransmitter release.

    PubMed

    Volman, Vladislav; Gerkin, Richard C

    2011-04-01

    Small networks of cultured hippocampal neurons respond to transient stimulation with rhythmic network activity (reverberation) that persists for several seconds, constituting an in vitro model of synchrony, working memory, and seizure. This mode of activity has been shown theoretically and experimentally to depend on asynchronous neurotransmitter release (an essential feature of the developing hippocampus) and is supported by a variety of developing neuronal networks despite variability in the size of populations (10-200 neurons) and in patterns of synaptic connectivity. It has previously been reported in computational models that "small-world" connection topology is ideal for the propagation of similar modes of network activity, although this has been shown only for neurons utilizing synchronous (phasic) synaptic transmission. We investigated how topological constraints on synaptic connectivity could shape the stability of reverberations in small networks that also use asynchronous synaptic transmission. We found that reverberation duration in such networks was resistant to changes in topology and scaled poorly with network size. However, normalization of synaptic drive, by reducing the variance of synaptic input across neurons, stabilized reverberation in such networks. Our results thus suggest that the stability of both normal and pathological states in developing networks might be shaped by variance-normalizing constraints on synaptic drive. We offer an experimental prediction for the consequences of such regulation on the behavior of small networks.

  1. Glutathionylation Mediates Angiotensin II–Induced eNOS Uncoupling, Amplifying NADPH Oxidase‐Dependent Endothelial Dysfunction

    PubMed Central

    Galougahi, Keyvan Karimi; Liu, Chia‐Chi; Gentile, Carmine; Kok, Cindy; Nunez, Andrea; Garcia, Alvaro; Fry, Natasha A. S.; Davies, Michael J.; Hawkins, Clare L.; Rasmussen, Helge H.; Figtree, Gemma A.

    2014-01-01

    Background Glutathionylation of endothelial nitric oxide synthase (eNOS) “uncouples” the enzyme, switching its function from nitric oxide (NO) to O2•− generation. We examined whether this reversible redox modification plays a role in angiotensin II (Ang II)‐induced endothelial dysfunction. Methods and Results Ang II increased eNOS glutathionylation in cultured human umbilical vein endothelial cells (HUVECs), rabbit aorta, and human arteries in vitro. This was associated with decreased NO bioavailability and eNOS activity as well as increased O2•− generation. Ang II‐induced decrease in eNOS activity was mediated by glutathionylation, as shown by restoration of function by glutaredoxin‐1. Moreover, Ang II‐induced increase in O2•− and decrease in NO were abolished in HUVECs transiently transfected, with mutant eNOS rendered resistant to glutathionylation. Ang II effects were nicotinamide adenine dinucleotide phosphate (NADPH) oxidase dependent because preincubation with gp 91ds‐tat, an inhibitor of NADPH oxidase, abolished the increase in eNOS glutathionylation and loss of eNOS activity. Functional significance of glutathionylation in intact vessels was supported by Ang II‐induced impairment of endothelium‐dependent vasorelaxation that was abolished by the disulfide reducing agent, dithiothreitol. Furthermore, attenuation of Ang II signaling in vivo by administration of an angiotensin converting enzyme (ACE) inhibitor reduced eNOS glutathionylation, increased NO, diminished O2•−, improved endothelium‐dependent vasorelaxation and reduced blood pressure. Conclusions Uncoupling of eNOS by glutathionylation is a key mediator of Ang II‐induced endothelial dysfunction, and its reversal is a mechanism for cardiovascular protection by ACE inhibition. We suggest that Ang II‐induced O2•− generation in endothelial cells, although dependent on NADPH oxidase, is amplified by glutathionylation‐dependent eNOS uncoupling. PMID:24755153

  2. Persistent Observation of Dynamic Scenes in an Active Camera Network

    NASA Astrophysics Data System (ADS)

    Song, Bi; Ding, Chong; Roy-Chowdhury, Amit; Farrell, Jay

    This chapter deals with the problem of persistent observation of a wide area scene through decentralized, cooperative control of an active camera network. We focus on applications where events unfold over a large geographic area and need to be analyzed by multiple cameras. There is no central unit accumulating and analyzing all the data. The overall goal is to observe all objects (i.e., targets) in the region of deployment of the cameras, while selectively focusing at a high resolution on some particular target features based on application requirements. Efficient usage of resources in such a scenario requires that the cameras be active. However, this control cannot be based on separate analysis of the sensed video in each camera. They must act collaboratively to be able to acquire multiple targets at different resolutions. Our research focuses on developing accurate and efficient target acquisition and camera control algorithms in such scenarios using game theory. We show real-life experimental results of the approach.

  3. Vascular nitric oxide: Beyond eNOS.

    PubMed

    Zhao, Yingzi; Vanhoutte, Paul M; Leung, Susan W S

    2015-10-01

    As the first discovered gaseous signaling molecule, nitric oxide (NO) affects a number of cellular processes, including those involving vascular cells. This brief review summarizes the contribution of NO to the regulation of vascular tone and its sources in the blood vessel wall. NO regulates the degree of contraction of vascular smooth muscle cells mainly by stimulating soluble guanylyl cyclase (sGC) to produce cyclic guanosine monophosphate (cGMP), although cGMP-independent signaling [S-nitrosylation of target proteins, activation of sarco/endoplasmic reticulum calcium ATPase (SERCA) or production of cyclic inosine monophosphate (cIMP)] also can be involved. In the blood vessel wall, NO is produced mainly from l-arginine by the enzyme endothelial nitric oxide synthase (eNOS) but it can also be released non-enzymatically from S-nitrosothiols or from nitrate/nitrite. Dysfunction in the production and/or the bioavailability of NO characterizes endothelial dysfunction, which is associated with cardiovascular diseases such as hypertension and atherosclerosis. PMID:26499181

  4. The persistence of equatorial spread F - an analysis on seasonal, solar activity and geomagnetic activity aspects

    NASA Astrophysics Data System (ADS)

    Sreeja, V.; Devasia, C. V.; Ravindran, Sudha; Sridharan, R.

    2009-02-01

    The persistence (duration) of Equatorial Spread F (ESF), which has significant impact on communication systems, is addressed. Its behavior during different seasons and geomagnetic activity levels under the solar maximum (2001) and minimum (2006) conditions, is reported using the data from the magnetic equatorial location of Trivandrum (8.5° N; 77° E; dip 0.5° N) in India. The study reveals that the persistence of the irregularities can be estimated to a reasonable extent by knowing the post sunset F region vertical drift velocity (Vz) and the magnetic activity index Kp. Any sort of advance information on the possible persistence of the ionospheric irregularities responsible for ESF is important for understanding the scintillation morphology, and the results which form the first step in this direction are presented and discussed.

  5. Removal of Persistent Organic Contaminants by Electrochemically Activated Sulfate.

    PubMed

    Farhat, Ali; Keller, Jurg; Tait, Stephan; Radjenovic, Jelena

    2015-12-15

    Solutions of sulfate have often been used as background electrolytes in the electrochemical degradation of contaminants and have been generally considered inert even when high-oxidation-power anodes such as boron-doped diamond (BDD) were employed. This study examines the role of sulfate by comparing electro-oxidation rates for seven persistent organic contaminants at BDD anodes in sulfate and inert nitrate anolytes. Sulfate yielded electro-oxidation rates 10-15 times higher for all target contaminants compared to the rates of nitrate anolyte. This electrochemical activation of sulfate was also observed at concentrations as low as 1.6 mM, which is relevant for many wastewaters. Electrolysis of diatrizoate in the presence of specific radical quenchers (tert-butanol and methanol) had a similar effect on electro-oxidation rates, illustrating a possible role of the hydroxyl radical ((•)OH) in the anodic formation of sulfate radical (SO4(•-)) species. The addition of 0.55 mM persulfate increased the electro-oxidation rate of diatrizoate in nitrate from 0.94 to 9.97 h(-1), suggesting a nonradical activation of persulfate. Overall findings indicate the formation of strong sulfate-derived oxidant species at BDD anodes when polarized at high potentials. This may have positive implications in the electro-oxidation of wastewaters containing sulfate. For example, the energy required for the 10-fold removal of diatrizoate was decreased from 45.6 to 2.44 kWh m(-3) by switching from nitrate to sulfate anolyte.

  6. Removal of Persistent Organic Contaminants by Electrochemically Activated Sulfate.

    PubMed

    Farhat, Ali; Keller, Jurg; Tait, Stephan; Radjenovic, Jelena

    2015-12-15

    Solutions of sulfate have often been used as background electrolytes in the electrochemical degradation of contaminants and have been generally considered inert even when high-oxidation-power anodes such as boron-doped diamond (BDD) were employed. This study examines the role of sulfate by comparing electro-oxidation rates for seven persistent organic contaminants at BDD anodes in sulfate and inert nitrate anolytes. Sulfate yielded electro-oxidation rates 10-15 times higher for all target contaminants compared to the rates of nitrate anolyte. This electrochemical activation of sulfate was also observed at concentrations as low as 1.6 mM, which is relevant for many wastewaters. Electrolysis of diatrizoate in the presence of specific radical quenchers (tert-butanol and methanol) had a similar effect on electro-oxidation rates, illustrating a possible role of the hydroxyl radical ((•)OH) in the anodic formation of sulfate radical (SO4(•-)) species. The addition of 0.55 mM persulfate increased the electro-oxidation rate of diatrizoate in nitrate from 0.94 to 9.97 h(-1), suggesting a nonradical activation of persulfate. Overall findings indicate the formation of strong sulfate-derived oxidant species at BDD anodes when polarized at high potentials. This may have positive implications in the electro-oxidation of wastewaters containing sulfate. For example, the energy required for the 10-fold removal of diatrizoate was decreased from 45.6 to 2.44 kWh m(-3) by switching from nitrate to sulfate anolyte. PMID:26572594

  7. Essentially nonoscillatory (ENO) reconstructions via extrapolation

    NASA Technical Reports Server (NTRS)

    Suresh, Ambady; Jorgenson, Philip C. E.

    1995-01-01

    In this paper, the algorithm for determining the stencil of a one-dimensional Essentially Nonoscillatory (ENO) reconstruction scheme on a uniform grid is reinterpreted as being based on extrapolation. This view leads to another extension of ENO reconstruction schemes to two-dimensional unstructured triangular meshes. The key idea here is to select several cells of the stencil in one step based on extrapolation rather than one cell at a time. Numerical experiments confirm that the new scheme yields sharp nonoscillatory reconstructions and that it is about five times faster than previous schemes.

  8. Space chimp Enos returns to Patrick Air Force Base

    NASA Technical Reports Server (NTRS)

    1961-01-01

    Enos the chimpanzee that orbited the earth twice in a Mercury spacecraft arrives back at Patrick Air Force Base. Enos landed some 220 nautical miles south of Bermuda and was picked up up by the U.S.S. Stormes.

  9. Disruption of a Spermatogenic Cell-Specific Mouse Enolase 4 (Eno4) Gene Causes Sperm Structural Defects and Male Infertility1

    PubMed Central

    Nakamura, Noriko; Dai, Qunsheng; Williams, Jason; Goulding, Eugenia H.; Willis, William D.; Brown, Paula R.; Eddy, Edward M.

    2013-01-01

    ABSTRACT Sperm utilize glycolysis to generate ATP required for motility, and several spermatogenic cell-specific glycolytic isozymes are associated with the fibrous sheath (FS) in the principal piece of the sperm flagellum. We used proteomics and molecular biology approaches to confirm earlier reports that a novel enolase is present in mouse sperm. We then found that a pan-enolase antibody, but not antibodies to ENO2 and ENO3, recognized a protein in the principal piece of the mouse sperm flagellum. Database analyses identified two previously uncharacterized enolase family-like candidate genes, 64306537H0Rik and Gm5506. Northern analysis indicated that 64306537H0Rik (renamed Eno4) was transcribed in testes of mice by Postnatal Day 12. To determine the role of ENO4, we generated mice using embryonic stem cells in which an Eno4 allele was disrupted by a gene trap containing a beta galactosidase (beta-gal) reporter (Eno4+/Gt). Expression of beta-gal occurred in the testis, and male mice homozygous for the gene trap allele (Eno4Gt/Gt) were infertile. Epididymal sperm numbers were 2-fold lower and sperm motility was reduced substantially in Eno4Gt/Gt mice compared to wild-type mice. Sperm from Eno4Gt/Gt mice had a coiled flagellum and a disorganized FS. The Gm5506 gene encodes a protein identical to ENO1 and also is transcribed at a low level in testis. We conclude that ENO4 is required for normal assembly of the FS and provides most of the enolase activity in sperm and that Eno1 and/or Gm5506 may encode a minor portion of the enolase activity in sperm. PMID:23446454

  10. Sustained hypertension despite endothelial-specific eNOS rescue in eNOS-deficient mice.

    PubMed

    Suvorava, Tatsiana; Stegbauer, Johannes; Thieme, Manuel; Pick, Stephanie; Friedrich, Sebastian; Rump, Lars C; Hohlfeld, Thomas; Kojda, Georg

    2015-03-13

    The aim of the study was to evaluate the possible contribution of non-endothelial eNOS to the regulation of blood pressure (BP). To accomplish this, a double transgenic strain expressing eNOS exclusively in the vascular endothelium (eNOS-Tg/KO) has been generated by endothelial-specific targeting of bovine eNOS in eNOS-deficient mice (eNOS-KO). Expression of eNOS was evaluated in aorta, myocardium, kidney, brain stem and skeletal muscle. Organ bath studies revealed a complete normalization of aortic reactivity to acetylcholine, phenylephrine and the NO-donors in eNOS-Tg/KO. Function of eNOS in resistance arteries was demonstrated by acute i.v. infusion of acetylcholine and the NOS-inhibitor L-NAME. Acetylcholine decreased mean arterial pressure in all strains but eNOS-KO responded significantly less sensitive as compared eNOS-Tg/KO and C57BL/6. Likewise, acute i.v. L-NAME application elevated mean arterial pressure in C57BL/6 and eNOS-Tg/KO, but not in eNOS-KO. In striking contrast to these findings, mean, systolic and diastolic BP in eNOS-Tg/KO remained significantly elevated and was similar to values of eNOS-KO. Chronic oral treatment with L-NAME increased BP to the level of eNOS-KO only in C57BL/6, but had no effect on hypertension in eNOS-KO and eNOS-Tg/KO. Taken together, functional reconstitution of eNOS in the vasculature of eNOS-KO not even partially lowered BP. These data suggest that the activity of eNOS expressed in non-vascular tissue might play a role in physiologic BP regulation. PMID:25680465

  11. S-glutathionylation uncouples eNOS and regulates its cellular and vascular function

    PubMed Central

    Chen, Chun-An; Wang, Tse-Yao; Varadharaj, Saradhadevi; Reyes, Levy A.; Hemann, Craig; Hassan Talukder, M. A.; Chen, Yeong-Renn; Druhan, Lawrence J.; Zweier, Jay L.

    2012-01-01

    Endothelial nitric oxide synthase (eNOS) is critical in the regulation of vascular function, and can generate both nitric oxide (NO) and superoxide (O2•−), which are key mediators of cellular signalling. In the presence of Ca2+/calmodulin, eNOS produces NO, endothelial-derived relaxing factor, from L-arginine (L-Arg) by means of electron transfer from NADPH through a flavin containing reductase domain to oxygen bound at the haem of an oxygenase domain, which also contains binding sites for tetrahydrobiopterin (BH4) and L-Arg1–3. In the absence of BH4, NO synthesis is abrogated and instead O2•− is generated4–7. While NOS dysfunction occurs in diseases with redox stress, BH4 repletion only partly restores NOS activity and NOS-dependent vasodilation7. This suggests that there is an as yet unidentified redox-regulated mechanism controlling NOS function. Protein thiols can undergo S-glutathionylation, a reversible protein modification involved in cellular signalling and adaptation8,9. Under oxidative stress, S-glutathionylation occurs through thiol–disulphide exchange with oxidized glutathione or reaction of oxidant-induced protein thiyl radicals with reduced glutathione10,11. Cysteine residues are critical for the maintenance of eNOS function12,13; we therefore speculated that oxidative stress could alter eNOS activity through S-glutathionylation. Here we show that S-glutathionylation of eNOS reversibly decreases NOS activity with an increase in O2•− generation primarily from the reductase, in which two highly conserved cysteine residues are identified as sites of S-glutathionylation and found to be critical for redox-regulation of eNOS function. We show that eNOS S-glutathionylation in endothelial cells, with loss of NO and gain of O2•− generation, is associated with impaired endothelium-dependent vasodilation. In hypertensive vessels, eNOS S-glutathionylation is increased with impaired endothelium-dependent vasodilation that is restored by thiol

  12. Mechanisms and Consequences of eNOS Dysfunction in Hypertension

    PubMed Central

    Li, Qiang; Yon, Ji-Youn; Cai, Hua

    2016-01-01

    Reduced nitric oxide (NO) bioavailability contributes to endothelial dysfunction and hypertension. The endothelial isoform of NO synthase (eNOS) is responsible for the production of NO within endothelium. Loss of eNOS cofactor tetrahydrobiopterin to initial increase in oxidative stress leads to uncoupling of eNOS, in which the enzyme produces superoxide anion rather than NO, further substantiating oxidative stress to induce vascular pathogenesis. The current review focuses on recent advances on the molecular mechanisms and consequences of eNOS dysfunction in hypertension, and potential novel therapeutic strategies restoring eNOS function to treat hypertension. PMID:25882860

  13. The Akt1-eNOS axis illustrates the specificity of kinase-substrate relationships in vivo.

    PubMed

    Schleicher, Michael; Yu, Jun; Murata, Takahisa; Derakhshan, Berhad; Atochin, Dimitriy; Qian, Li; Kashiwagi, Satoshi; Di Lorenzo, Annarita; Harrison, Kenneth D; Huang, Paul L; Sessa, William C

    2009-01-01

    Akt1 is critical for many in vivo functions; however, the cell-specific substrates responsible remain to be defined. Here, we examine the importance of endothelial nitric oxide synthase (eNOS) as an Akt1 substrate by generating Akt1-deficient mice (Akt1(-/-) mice) carrying knock-in mutations (serine to aspartate or serine to alanine substitutions) of the critical Akt1 phosphorylation site on eNOS (serine 1176) that render the enzyme "constitutively active" or "less active." The eNOS mutations did not influence several phenotypes in Akt1(-/-) mice; however, the defective postnatal angiogenesis characteristic of Akt1(-/-) mice was rescued by crossing the Akt1(-/-) mice with mice carrying the constitutively active form of eNOS, but not by crossing with mice carrying the less active eNOS mutant. This genetic rescue resulted in the stabilization of hypoxia-inducible factor 1alpha (HIF-1alpha) and increased production of HIF-1alpha-responsive genes in vivo and in vitro. Thus, Akt1 regulates angiogenesis largely through phosphorylation of eNOS and NO-dependent signaling. PMID:19654415

  14. The Akt1-eNOS axis illustrates the specificity of kinase-substrate relationships in vivo.

    PubMed

    Schleicher, Michael; Yu, Jun; Murata, Takahisa; Derakhshan, Berhad; Atochin, Dimitriy; Qian, Li; Kashiwagi, Satoshi; Di Lorenzo, Annarita; Harrison, Kenneth D; Huang, Paul L; Sessa, William C

    2009-08-04

    Akt1 is critical for many in vivo functions; however, the cell-specific substrates responsible remain to be defined. Here, we examine the importance of endothelial nitric oxide synthase (eNOS) as an Akt1 substrate by generating Akt1-deficient mice (Akt1(-/-) mice) carrying knock-in mutations (serine to aspartate or serine to alanine substitutions) of the critical Akt1 phosphorylation site on eNOS (serine 1176) that render the enzyme "constitutively active" or "less active." The eNOS mutations did not influence several phenotypes in Akt1(-/-) mice; however, the defective postnatal angiogenesis characteristic of Akt1(-/-) mice was rescued by crossing the Akt1(-/-) mice with mice carrying the constitutively active form of eNOS, but not by crossing with mice carrying the less active eNOS mutant. This genetic rescue resulted in the stabilization of hypoxia-inducible factor 1alpha (HIF-1alpha) and increased production of HIF-1alpha-responsive genes in vivo and in vitro. Thus, Akt1 regulates angiogenesis largely through phosphorylation of eNOS and NO-dependent signaling.

  15. Possible involvement of PPARγ-associated eNOS signaling activation in rosuvastatin-mediated prevention of nicotine-induced experimental vascular endothelial abnormalities.

    PubMed

    Kathuria, Sonam; Mahadevan, Nanjaian; Balakumar, Pitchai

    2013-02-01

    Nicotine exposure via cigarette smoking and tobacco chewing is associated with vascular complications. The present study investigated the effect of rosuvastatin in nicotine (2 mg/kg/day, i.p., 4 weeks)-induced vascular endothelial dysfunction (VED) in rats. The development of VED was assessed by employing isolated aortic ring preparation and estimating aortic and serum nitrite/nitrate concentration. Further, scanning electron microscopy and hematoxylin-eosin staining of thoracic aorta were performed to assess the vascular endothelial integrity. Moreover, oxidative stress was assessed by estimating aortic superoxide anion generation and serum thiobarbituric acid-reactive substances. The nicotine administration produced VED by markedly reducing acetylcholine-induced endothelium-dependent relaxation, impairing the integrity of vascular endothelium, decreasing aortic and serum nitrite/nitrate concentration, increasing oxidative stress, and inducing lipid alteration. However, treatment with rosuvastatin (10 mg/kg/day, i.p., 4 weeks) markedly attenuated nicotine-induced vascular endothelial abnormalities, oxidative stress, and lipid alteration. Interestingly, the co-administration of peroxisome proliferator-activated receptor γ (PPARγ) antagonist, GW9662 (1 mg/kg/day, i.p., 2 weeks) submaximally, significantly prevented rosuvastatin-induced improvement in vascular endothelial integrity, endothelium-dependent relaxation, and nitrite/nitrate concentration in rats administered nicotine. However, GW9662 co-administration did not affect rosuvastatin-associated vascular anti-oxidant and lipid-lowering effects. The incubation of aortic ring, isolated from rosuvastatin-treated nicotine-administered rats, with L-NAME (100 μM), an inhibitor of nitric oxide synthase (NOS), significantly attenuated rosuvastatin-induced improvement in acetylcholine-induced endothelium-dependent relaxation. Rosuvastatin prevents nicotine-induced vascular endothelial abnormalities by activating

  16. Overexpression of arginase in the aged mouse penis impairs erectile function and decreases eNOS activity: influence of in vivo gene therapy of anti-arginase.

    PubMed

    Bivalacqua, Trinity J; Burnett, Arthur L; Hellstrom, Wayne J G; Champion, Hunter C

    2007-03-01

    Since both increased nitric oxide (NO) synthase (NOS) abundance and diminished NO signaling have been reported in the aging penis, the role of NO in the adaptations of aging remains controversial. Here we tested the hypothesis that arginase, an enzyme that competes with NOS for the substrate l-arginine, contributes to erectile dysfunction with advanced age in the B6/129 mouse strain. Arginase protein abundance, mRNA expression, and enzyme activity were elevated in aged compared with young penile endothelial cells. In addition, endothelial NOS (NOS3) protein abundance was greater in aged versus young penile endothelial cells, whereas NOS activity and cGMP levels were reduced. Calcium-dependent l-arginine-to-l-citrulline conversion and cGMP formation increased significantly in aged mouse penes in the presence of the arginase inhibitor 2(S)-amino-6-boronohexanoic acid (ABH). However, there was no effect on l-arginine-to-l-citrulline conversion or cGMP accumulation in the endothelium from young mouse penes. To assess the functional role of arginase in the inhibition of NOS pathway responsiveness in the penis, we evaluated the effects of ABH and an adeno-associated virus encoding an antisense sequence to arginase I (AAVanti-arginase) on erectile function in vivo. ABH and AAVanti-arginase enhanced endothelium-dependent erectile responses in the aged mice without altering endothelium-independent responses. Paralleling our in vitro observations, ABH or AAVanti-arginase did not affect vascular responses in the young mice. Inhibition of the arginase pathway improves endothelial function in the aging penile circulation, suggesting that the arginase pathway may be exploited to improve erectile dysfunction associated with aging. PMID:17071735

  17. Identification of Anti-Persister Activity against Uropathogenic Escherichia coli from a Clinical Drug Library

    PubMed Central

    Niu, Hongxia; Cui, Peng; Shi, Wanliang; Zhang, Shuo; Feng, Jie; Wang, Yong; Sullivan, David; Zhang, Wenhong; Zhu, Bingdong; Zhang, Ying

    2015-01-01

    Uropathogenic E. coli is a major cause of urinary tract infections (UTIs), but current antibiotics do not always effectively clear the persistent infection. To identify drugs that eliminate uropathogenic E. coli persisters, we screened a clinical drug library consisting of 1524 compounds using high throughput drug exposure assay in 96-well plates. Bacterial survival was assessed by growth on LB plates. We identified 14 drug candidates (tosufloxacin, colistin, sparfloxacin, moxifloxacin and gatifloxacin, enrofloxacin and sarafloxacin, octodrine, clofoctol, dibekacin, cephalosporin C, pazufloxacin, streptomycin and neomycin), which had high anti-persister activity. Among them, tosufloxacin and colistin had the highest anti-persister activity and could completely eradicate E. coli persisters in 3 days in vitro while the current UTI antibiotics failed to do so. Our findings may have implications for the development of a more effective treatment for UTIs. PMID:27025620

  18. eNOS polymorphisms and clinical outcome in advanced HCC patients receiving sorafenib: final results of the ePHAS study.

    PubMed

    Casadei Gardini, Andrea; Marisi, Giorgia; Faloppi, Luca; Scarpi, Emanuela; Foschi, Francesco Giuseppe; Iavarone, Massimo; Lauletta, Gianfranco; Corbelli, Jody; Valgiusti, Martina; Facchetti, Floriana; Della Corte, Cristina; Neri, Luca Maria; Tamberi, Stefano; Cascinu, Stefano; Scartozzi, Mario; Amadori, Dino; Nanni, Oriana; Tenti, Elena; Ulivi, Paola; Frassineti, Giovanni Luca

    2016-05-10

    Sorafenib may reduce endothelial nitric oxide synthase (eNOS) activity by inhibiting vascular endothelial growth factor receptors (VEGF-R), leading to a decrease in nitric oxide production. In the Italian multicenter ePHAS (eNOS polymorphisms in HCC and sorafenib) study, we analyzed the role of eNOS polymorphisms in relation to clinical outcome in patients with hepatocellular carcinoma (HCC) receiving sorafenib. Our retrospective study included a training cohort of 41 HCC patients and a validation cohort of 87 HCC patients, all undergoing sorafenib treatment. Three eNOS polymorphisms (eNOS -786T>C, eNOS VNTR 27bp 4a/b and eNOS+894G>T) were analyzed by direct sequencing or Real Time PCR in relation to progression-free survival (PFS) and overall survival (OS) (log-rank test). In univariate analysis, training cohort patients homozygous for eNOS haplotype (HT1:T-4b at eNOS-786/eNOS VNTR) had a lower median PFS (2.6 vs. 5.8 months, P < 0.0001) and OS (3.2 vs.14.6 months, P = 0.024) than those with other haplotypes. In the validation set, patients homozygous for HT1 had a lower median PFS (2.0 vs. 6.7 months, P < 0.0001) and OS (6.4 vs.18.0 months, P < 0.0001) than those with other haplotypes. Multivariate analysis confirmed this haplotype as the only independent prognostic factor. Our results suggest that haplotype HT1 in the eNOS gene may be capable of identifying a subset of HCC patients who are resistant to sorafenib. PMID:27058899

  19. eNOS polymorphisms and clinical outcome in advanced HCC patients receiving sorafenib: final results of the ePHAS study

    PubMed Central

    Faloppi, Luca; Scarpi, Emanuela; Foschi, Francesco Giuseppe; Iavarone, Massimo; Lauletta, Gianfranco; Corbelli, Jody; Valgiusti, Martina; Facchetti, Floriana; Corte, Cristina della; Neri, Luca Maria; Tamberi, Stefano; Cascinu, Stefano; Scartozzi, Mario; Amadori, Dino; Nanni, Oriana; Tenti, Elena

    2016-01-01

    Sorafenib may reduce endothelial nitric oxide synthase (eNOS) activity by inhibiting vascular endothelial growth factor receptors (VEGF-R), leading to a decrease in nitric oxide production. In the Italian multicenter ePHAS (eNOS polymorphisms in HCC and sorafenib) study, we analyzed the role of eNOS polymorphisms in relation to clinical outcome in patients with hepatocellular carcinoma (HCC) receiving sorafenib. Our retrospective study included a training cohort of 41 HCC patients and a validation cohort of 87 HCC patients, all undergoing sorafenib treatment. Three eNOS polymorphisms (eNOS -786T>C, eNOS VNTR 27bp 4a/b and eNOS+894G>T) were analyzed by direct sequencing or Real Time PCR in relation to progression-free survival (PFS) and overall survival (OS) (log-rank test). In univariate analysis, training cohort patients homozygous for eNOS haplotype (HT1:T-4b at eNOS-786/eNOS VNTR) had a lower median PFS (2.6 vs. 5.8 months, P < 0.0001) and OS (3.2 vs.14.6 months, P = 0.024) than those with other haplotypes. In the validation set, patients homozygous for HT1 had a lower median PFS (2.0 vs. 6.7 months, P < 0.0001) and OS (6.4 vs.18.0 months, P < 0.0001) than those with other haplotypes. Multivariate analysis confirmed this haplotype as the only independent prognostic factor. Our results suggest that haplotype HT1 in the eNOS gene may be capable of identifying a subset of HCC patients who are resistant to sorafenib. PMID:27058899

  20. eNOS polymorphisms and clinical outcome in advanced HCC patients receiving sorafenib: final results of the ePHAS study.

    PubMed

    Casadei Gardini, Andrea; Marisi, Giorgia; Faloppi, Luca; Scarpi, Emanuela; Foschi, Francesco Giuseppe; Iavarone, Massimo; Lauletta, Gianfranco; Corbelli, Jody; Valgiusti, Martina; Facchetti, Floriana; Della Corte, Cristina; Neri, Luca Maria; Tamberi, Stefano; Cascinu, Stefano; Scartozzi, Mario; Amadori, Dino; Nanni, Oriana; Tenti, Elena; Ulivi, Paola; Frassineti, Giovanni Luca

    2016-05-10

    Sorafenib may reduce endothelial nitric oxide synthase (eNOS) activity by inhibiting vascular endothelial growth factor receptors (VEGF-R), leading to a decrease in nitric oxide production. In the Italian multicenter ePHAS (eNOS polymorphisms in HCC and sorafenib) study, we analyzed the role of eNOS polymorphisms in relation to clinical outcome in patients with hepatocellular carcinoma (HCC) receiving sorafenib. Our retrospective study included a training cohort of 41 HCC patients and a validation cohort of 87 HCC patients, all undergoing sorafenib treatment. Three eNOS polymorphisms (eNOS -786T>C, eNOS VNTR 27bp 4a/b and eNOS+894G>T) were analyzed by direct sequencing or Real Time PCR in relation to progression-free survival (PFS) and overall survival (OS) (log-rank test). In univariate analysis, training cohort patients homozygous for eNOS haplotype (HT1:T-4b at eNOS-786/eNOS VNTR) had a lower median PFS (2.6 vs. 5.8 months, P < 0.0001) and OS (3.2 vs.14.6 months, P = 0.024) than those with other haplotypes. In the validation set, patients homozygous for HT1 had a lower median PFS (2.0 vs. 6.7 months, P < 0.0001) and OS (6.4 vs.18.0 months, P < 0.0001) than those with other haplotypes. Multivariate analysis confirmed this haplotype as the only independent prognostic factor. Our results suggest that haplotype HT1 in the eNOS gene may be capable of identifying a subset of HCC patients who are resistant to sorafenib.

  1. Changes in eNOS phosphorylation contribute to increased arteriolar NO release during juvenile growth

    PubMed Central

    Kang, Lori S.; Nurkiewicz, Timothy R.; Wu, Guoyao

    2012-01-01

    Nitric oxide (NO) mediates a major portion of arteriolar endothelium-dependent dilation in adults, but indirect evidence has suggested that NO contributes minimally to these responses in the young. Isolated segments of arterioles were studied in vitro to verify this age-related increase in NO release and investigate the mechanism by which it occurs. Directly measured NO release induced by ACh or the Ca2+ ionophore A-23187 was five- to sixfold higher in gracilis muscle arterioles from 42- to 46-day-old (juvenile) rats than in those from 25- to 28-day-old (weanling) rats. There were no differences between groups in arteriolar endothelial NO synthase (eNOS) expression or tetrahydrobiopterin levels, and arteriolar l-arginine levels were lower in juvenile vessels than in weanling vessels (104 ± 6 vs.126 ± 3 pmol/mg). In contrast, agonist-induced eNOS Thr495 dephosphorylation and eNOS Ser1177 phosphorylation (events required for maximal activity) were up to 30% and 65% greater, respectively, in juvenile vessels. Juvenile vessels did not show increased expression of enzymes that mediate these events [protein phosphatases 1 and 2A and PKA and PKB (Akt)] or heat shock protein 90, which facilitates Ser1177 phosphorylation. However, agonist-induced colocalization of heat shock protein 90 with eNOS was 34–66% greater in juvenile vessels than in weanling vessels, and abolition of this difference with geldanamycin also abolished the difference in Ser1177 phosphorylation between groups. These findings suggest that growth-related increases in arteriolar NO bioavailability may be due at least partially to changes in the regulation of eNOS phosphorylation and increased signaling activity, with no change in the abundance of eNOS signaling proteins. PMID:22140037

  2. Spatial Patterns of Persistent Neural Activity Vary with the Behavioral Context of Short-Term Memory

    PubMed Central

    Daie, Kayvon

    2015-01-01

    Summary A short-term memory can be evoked by different inputs and control separate targets in different behavioral contexts. To address the circuit mechanisms underlying context-dependent memory function, we determined through optical imaging how memory is encoded at the whole-network level in two behavioral settings. Persistent neural activity maintaining a memory of desired eye position was imaged throughout the oculomotor integrator after saccadic or optokinetic stimulation. While eye position was encoded by the amplitude of network activity, the spatial patterns of firing were context-dependent: cells located caudally generally were most persistent following saccadic input, whereas cells located rostrally were most persistent following optokinetic input. To explain these data, we computationally identified four independent modes of network activity and found these were differentially accessed by saccadic and optokinetic inputs. These results show how a circuit can simultaneously encode memory value and behavioral context, respectively, in its amplitude and spatial pattern of persistent firing. PMID:25661184

  3. Persistently Active Microbial Molecules Prolong Innate Immune Tolerance In Vivo

    PubMed Central

    Lu, Mingfang; Varley, Alan W.; Munford, Robert S.

    2013-01-01

    Measures that bolster the resolution phase of infectious diseases may offer new opportunities for improving outcome. Here we show that inactivation of microbial lipopolysaccharides (LPS) can be required for animals to recover from the innate immune tolerance that follows exposure to Gram-negative bacteria. When wildtype mice are exposed to small parenteral doses of LPS or Gram-negative bacteria, their macrophages become reprogrammed (tolerant) for a few days before they resume normal function. Mice that are unable to inactivate LPS, in contrast, remain tolerant for several months; during this time they respond sluggishly to Gram-negative bacterial challenge, with high mortality. We show here that prolonged macrophage reprogramming is maintained in vivo by the persistence of stimulatory LPS molecules within the cells' in vivo environment, where naïve cells can acquire LPS via cell-cell contact or from the extracellular fluid. The findings provide strong evidence that inactivation of a stimulatory microbial molecule can be required for animals to regain immune homeostasis following parenteral exposure to bacteria. Measures that disable microbial molecules might enhance resolution of tissue inflammation and help restore innate defenses in individuals recovering from many different infectious diseases. PMID:23675296

  4. Contribution of eNOS variants to the genetic susceptibility of coronary artery disease in a Tunisian population.

    PubMed

    Ben Ali, Marwa; Messaoudi, Safia; Ezzine, Houda; Mahjoub, Touhami

    2015-04-01

    Nitric oxide (NO), produced by the enzyme endothelial nitric oxide synthase (eNOS), has critical roles in the regulation of vascular homeostasis and prevention of atherogenesis by inhibiting leukocytes, platelet activation, and smooth muscle cell proliferation. There is strong experimental and clinical evidence that abnormalities in eNOS availability play an important role in the pathophysiology of coronary artery disease (CAD). Controversial results regarding the association of eNOS gene polymorphisms with CAD have been reported. The aim of this study is to investigate the relationship of the 894G>T (rs1799983) and 4a/4b (rs61722009) polymorphisms of the eNOS gene with the presence of CAD in the Tunisian population. A total of 332 patients with CAD and 368 controls were included in this study. The 894G>T (rs1799983) single-nucleotide polymorphisms were analyzed by polymerase chain reaction-restriction fragment length polymorphism, and 4a/4b (rs61722009) polymorphism just by polymerase chain reaction (PCR). eNOS rs1799983 was significantly associated with CAD under the additive, dominant, but not recessive, models (additive model OR: 2.81; 95% CI [2.05-3.85]; p<0.001, dominant model OR: 2.84; 95% CI [2.09-3.86]; p<0.001, and recessive models p=0.09). This remained significant after adjustment for age, gender, diabetes, smoking, and hypertension. In contrast to eNOS rs1799983, eNOS rs61722009 was not associated with CAD under any of the genetic models tested. These findings suggest that the G894T (rs1799983) polymorphism of the eNOS gene was associated with CAD in Tunisian patients. PMID:25748584

  5. Induction and modulation of persistent activity in a layer V PFC microcircuit model

    PubMed Central

    Papoutsi, Athanasia; Sidiropoulou, Kyriaki; Cutsuridis, Vassilis; Poirazi, Panayiota

    2013-01-01

    Working memory refers to the temporary storage of information and is strongly associated with the prefrontal cortex (PFC). Persistent activity of cortical neurons, namely the activity that persists beyond the stimulus presentation, is considered the cellular correlate of working memory. Although past studies suggested that this type of activity is characteristic of large scale networks, recent experimental evidence imply that small, tightly interconnected clusters of neurons in the cortex may support similar functionalities. However, very little is known about the biophysical mechanisms giving rise to persistent activity in small-sized microcircuits in the PFC. Here, we present a detailed biophysically—yet morphologically simplified—microcircuit model of layer V PFC neurons that incorporates connectivity constraints and is validated against a multitude of experimental data. We show that (a) a small-sized network can exhibit persistent activity under realistic stimulus conditions. (b) Its emergence depends strongly on the interplay of dADP, NMDA, and GABAB currents. (c) Although increases in stimulus duration increase the probability of persistent activity induction, variability in the stimulus firing frequency does not consistently influence it. (d) Modulation of ionic conductances (Ih, ID, IsAHP, IcaL, IcaN, IcaR) differentially controls persistent activity properties in a location dependent manner. These findings suggest that modulation of the microcircuit's firing characteristics is achieved primarily through changes in its intrinsic mechanism makeup, supporting the hypothesis of multiple bi-stable units in the PFC. Overall, the model generates a number of experimentally testable predictions that may lead to a better understanding of the biophysical mechanisms of persistent activity induction and modulation in the PFC. PMID:24130519

  6. Activated ClpP kills persisters and eradicates a chronic biofilm infection.

    PubMed

    Conlon, B P; Nakayasu, E S; Fleck, L E; LaFleur, M D; Isabella, V M; Coleman, K; Leonard, S N; Smith, R D; Adkins, J N; Lewis, K

    2013-11-21

    Chronic infections are difficult to treat with antibiotics but are caused primarily by drug-sensitive pathogens. Dormant persister cells that are tolerant to killing by antibiotics are responsible for this apparent paradox. Persisters are phenotypic variants of normal cells and pathways leading to dormancy are redundant, making it challenging to develop anti-persister compounds. Biofilms shield persisters from the immune system, suggesting that an antibiotic for treating a chronic infection should be able to eradicate the infection on its own. We reasoned that a compound capable of corrupting a target in dormant cells will kill persisters. The acyldepsipeptide antibiotic (ADEP4) has been shown to activate the ClpP protease, resulting in death of growing cells. Here we show that ADEP4-activated ClpP becomes a fairly nonspecific protease and kills persisters by degrading over 400 proteins, forcing cells to self-digest. Null mutants of clpP arise with high probability, but combining ADEP4 with rifampicin produced complete eradication of Staphylococcus aureus biofilms in vitro and in a mouse model of a chronic infection. Our findings indicate a general principle for killing dormant cells-activation and corruption of a target, rather than conventional inhibition. Eradication of a biofilm in an animal model by activating a protease suggests a realistic path towards developing therapies to treat chronic infections.

  7. Alpha(1)-adrenergic-mediated eNOS phosphorylation in intact arteries.

    PubMed

    Looft-Wilson, Robin C; Todd, Sarah E; Araj, Christina A; Mutchler, Stephanie M; Goodell, Cara A Raphael

    2013-01-01

    Activation of arterial smooth muscle alpha(1)-adrenergic receptors results in vasoconstriction, as well as a secondary release of nitric oxide and slow vasodilation, presumably through gap junction communication from smooth muscle to endothelium. We hypothesized that this slow vasodilation is due to activation of eNOS through phosphorylation at Ser1179 and dephosphorylation at Thr495. Phosphorylation was measured by western blot using mouse mesenteric arteries that were cannulated and pressurized (75 mm Hg) and treated either by 1) 5 min of phenylephrine superfusion (10(-5)M) (PE5), 2) 15 min of phenylephrine (PE15), 3) 15 min phenylephrine followed by acetylcholine (10(-4)M) (PE+ACh), or 4) 20 min time control with no treatment (NT) [4-5 arteries pooled per treatment per blot; 5 blots performed]. These treatments allowed correlation between vasomotor changes, namely maximal constriction (PE5), slow vasodilation (PE15), and maximal dilation (PE+ACh), and relative phosphorylation changes. Phosphorylation of eNOS at Ser1179 was increased relative to NT by more than 2-fold at PE5 and remained similarly increased at PE15 and PE+ACh. Phosphorylation of eNOS at Thr495 was less in all treatments relative to NT, but not significantly. Treatment with L-NAME (10(-4)M) or endothelial denudation indicated that the slow dilation in response to phenylephrine was completely due to nitric oxide synthase and was endothelial dependent. These results indicate that eNOS phosphorylation at Ser1179 occurs before the slow dilation and is not actively involved in this vasodilation or dilation to acetylcholine, but may play a permissive role in eNOS activation by other mechanisms. It is not yet known what mechanism is responsible for Ser1179 phosphorylation with phenylephrine stimulation.

  8. Activated ClpP kills persisters and eradicates a chronic biofilm infection.

    SciTech Connect

    Conlon, Brian P.; Nakayasu, Ernesto S.; Fleck, Laura E.; LaFleur, Michael D.; Isabella, Vincent M.; Coleman, K.; Leonard, Steve N.; Smith, Richard D.; Adkins, Joshua N.; Lewis, Kim

    2013-11-21

    The current antibiotic crisis stems from two distinct phenomena-drug resistance, and drug tolerance. Resistance mechanisms such as drug efflux or modification prevent antibiotics from binding to their targets 1, allowing pathogens to grow. Antibiotic tolerance is the property of persister cells, phenotypic variants of regular bacteria 2. Antibiotics kill by corrupting targets, but these are inactive in dormant persisters, leading to tolerance. Persisters were first identified by Joseph Bigger in 1944, when he discovered a surviving sub-population of Staphylococcus following treatment with penicillin3. Persisters are largely responsible for recalcitrance of chronic diseases such as tuberculosis, and various infections associated with biofilms - endocarditis, osteomyelitis, infections of catheters and indwelling devices, and deep-seated infections of soft tissues 4. There are a number of redundant pathways involved in persister formation5,6 precluding development of drugs inhibiting their formation. The acyldepsipeptide antibiotic (ADEP 4) has been shown to activate the ClpP protease resulting in death of growing cells 7. Here we show that ADEP4 activated ClpP becomes a fairly non-specific protease and kills persister cells by degradation of over 400 intracellular targets. clpP mutants are resistant to ADEP4 7, but we find that they display increased susceptibility to killing by a range of conventional antibiotics. Combining ADEP4 with rifampicin leads to eradication of persisters, stationary and biofilm populations of Staphylococcus aureus in vitro and in a deep-seated murine infection. Target corruption/activation provides an approach to killing persisters and eradicating chronic infections.

  9. TRPC channels underlie cholinergic plateau potentials and persistent activity in entorhinal cortex.

    PubMed

    Zhang, Zizhen; Reboreda, Antonio; Alonso, Angel; Barker, Philip A; Séguéla, Philippe

    2011-04-01

    Persistent neuronal activity lasting seconds to minutes has been proposed to allow for the transient storage of memory traces in entorhinal cortex and thus could play a major role in working memory. Nonsynaptic plateau potentials induced by acetylcholine account for persistent firing in many cortical and subcortical structures. The expression of these intrinsic properties in cortical neurons involves the recruitment of a non-selective cation conductance. Despite its functional importance, the identity of the cation channels remains unknown. Here we show that, in layer V of rat medial entorhinal cortex, muscarinic receptor-evoked plateau potentials and persistent firing induced by carbachol require phospholipase C activation, decrease of PIP(2) levels, and permissive intracellular Ca(2+) concentrations. Plateau potentials and persistent activity were suppressed by the generic nonselective cation channel blockers FFA (100 μM) and 2-APB (100 μM), as well as by the TRPC channel blocker SKF-96365 (50 μM). However, plateau potentials were not affected by the TRPV channel blocker ruthenium red (40 μM). The TRPC3/6/7 activator OAG did not induce or enhance persistent firing evoked by carbachol. Voltage clamp recordings revealed a carbachol-activated, nonselective cationic current with a heteromeric TRPC-like phenotype. Moreover, plateau potentials and persistent firing were inhibited by intracellular application of the peptide EQVTTRL that disrupts interactions between the C-terminal domain of TRPC4/5 subunits and associated PDZ proteins. Altogether, our data suggest that TRPC cation channels mediating persistent muscarinic currents significantly contribute to the firing and mnemonic properties of projection neurons in the entorhinal cortex.

  10. Persistence of biologically active compounds in soil: Final report

    SciTech Connect

    Williams, S.E.

    1987-02-01

    This document describes the long-term effects of soil-applied oil shale process water on the VA fungi and Rhizobium bacteria in a native soil. Techniques include assessing the VA fungal activity at field treatment plots and using treated field soils in a bioassay to determine VA infection and Rhizobium-nodulation potentials four years after process water application. 52 refs., 32 figs., 2 tabs.

  11. The role of eNOS in the migration and proliferation of bone-marrow derived endothelial progenitor cells and in vitro angiogenesis.

    PubMed

    Lu, Aizhen; Wang, Libo; Qian, Liling

    2015-04-01

    The role of endothelial nitric oxide synthase (eNOS) in the activities of endothelial progenitor cells (EPCs) including migration, proliferation, and tube formation in vitro was investigated. EPCs were obtained from rat bone mononuclear cells by culturing for 7-10 days in EGM-2MV and identified by their capacity for FITC-UEA-1 binding and acetylated low-density lipoprotein (Dil-ac-LDL) intake using fluorescence microscopy. Migration, proliferation and tube formation activities were assessed in the presence or absence of N(ω)-nitro-L-argininemethylester (L-NAME), an eNOS inhibitor. mRNA and protein expression of CXCR4, CXCR7, VEGFR2, and eNOS were detected by real-time PCR and western blotting in the presence or absence of L-NAME. Nitric oxide production was detected by nitrate reductase in the presence or absence of L-NAME. Typical spindle-shaped cells appeared on the 7(th)-10(th) day and confluence reached about 80%. The percentage of FITC-UEA-1 and Dil-ac-LDL double-stained cells was about 85%. Cell migration, proliferation, and tube formation were significantly weakened after eNOS was inhibited (P < 0.05), and the expressions of CXCR4 and eNOS were significantly reduced (P < 0.05, respectively), but there was little change in CXCR7 and VEGFR2. NO production was dramatically decreased after eNOS was inhibited (P < 0.05). In summary, L-NAME significantly reduced the expression of eNOS and NO production by EPCs and inhibited migration, proliferation and tube formation by these cells, suggesting that eNOS affects EPC activities; CXCR4 may be implicated in the action of eNOS.

  12. Identification of novel activity against Borrelia burgdorferi persisters using an FDA approved drug library

    PubMed Central

    Feng, Jie; Wang, Ting; Shi, Wanliang; Zhang, Shuo; Sullivan, David; Auwaerter, Paul G; Zhang, Ying

    2014-01-01

    Although antibiotic treatment for Lyme disease is effective in the majority of cases, especially during the early phase of the disease, a minority of patients suffer from post-treatment Lyme disease syndrome (PTLDS). It is unclear what mechanisms drive this problem, and although slow or ineffective killing of Borrelia burgdorferi has been suggested as an explanation, there is a lack of evidence that viable organisms are present in PTLDS. Although not a clinical surrogate, insight may be gained by examining stationary-phase in vitro Borrelia burgdorferi persisters that survive treatment with the antibiotics doxycycline and amoxicillin. To identify drug candidates that can eliminate B. burgdorferi persisters more effectively, we screened an Food and Drug Administration (FDA)-approved drug library consisting of 1524 compounds against stationary-phase B. burgdorferi by using a newly developed high throughput SYBR Green I/propidium iodide (PI) assay. We identified 165 agents approved for use in other disease conditions that had more activity than doxycycline and amoxicillin against B. burgdorferi persisters. The top 27 drug candidates from the 165 hits were confirmed to have higher anti-persister activity than the current frontline antibiotics. Among the top 27 confirmed drug candidates from the 165 hits, daptomycin, clofazimine, carbomycin, sulfa drugs (e.g., sulfamethoxazole), and certain cephalosporins (e.g. cefoperazone) had the highest anti-persister activity. In addition, some drug candidates, such as daptomycin and clofazimine (which had the highest activity against non-growing persisters), had relatively poor activity or a high minimal inhibitory concentration (MIC) against growing B. burgdorferi. Our findings may have implications for the development of a more effective treatment for Lyme disease and for the relief of long-term symptoms that afflict some Lyme disease patients. PMID:26038747

  13. Identification of novel activity against Borrelia burgdorferi persisters using an FDA approved drug library.

    PubMed

    Feng, Jie; Wang, Ting; Shi, Wanliang; Zhang, Shuo; Sullivan, David; Auwaerter, Paul G; Zhang, Ying

    2014-07-01

    Although antibiotic treatment for Lyme disease is effective in the majority of cases, especially during the early phase of the disease, a minority of patients suffer from post-treatment Lyme disease syndrome (PTLDS). It is unclear what mechanisms drive this problem, and although slow or ineffective killing of Borrelia burgdorferi has been suggested as an explanation, there is a lack of evidence that viable organisms are present in PTLDS. Although not a clinical surrogate, insight may be gained by examining stationary-phase in vitro Borrelia burgdorferi persisters that survive treatment with the antibiotics doxycycline and amoxicillin. To identify drug candidates that can eliminate B. burgdorferi persisters more effectively, we screened an Food and Drug Administration (FDA)-approved drug library consisting of 1524 compounds against stationary-phase B. burgdorferi by using a newly developed high throughput SYBR Green I/propidium iodide (PI) assay. We identified 165 agents approved for use in other disease conditions that had more activity than doxycycline and amoxicillin against B. burgdorferi persisters. The top 27 drug candidates from the 165 hits were confirmed to have higher anti-persister activity than the current frontline antibiotics. Among the top 27 confirmed drug candidates from the 165 hits, daptomycin, clofazimine, carbomycin, sulfa drugs (e.g., sulfamethoxazole), and certain cephalosporins (e.g. cefoperazone) had the highest anti-persister activity. In addition, some drug candidates, such as daptomycin and clofazimine (which had the highest activity against non-growing persisters), had relatively poor activity or a high minimal inhibitory concentration (MIC) against growing B. burgdorferi. Our findings may have implications for the development of a more effective treatment for Lyme disease and for the relief of long-term symptoms that afflict some Lyme disease patients.

  14. The in vivo activation of persistent nanophosphors for optical imaging of vascularization, tumours and grafted cells

    NASA Astrophysics Data System (ADS)

    Maldiney, Thomas; Bessière, Aurélie; Seguin, Johanne; Teston, Eliott; Sharma, Suchinder K.; Viana, Bruno; Bos, Adrie J. J.; Dorenbos, Pieter; Bessodes, Michel; Gourier, Didier; Scherman, Daniel; Richard, Cyrille

    2014-04-01

    Optical imaging for biological applications requires more sensitive tools. Near-infrared persistent luminescence nanoparticles enable highly sensitive in vivo optical detection and complete avoidance of tissue autofluorescence. However, the actual generation of persistent luminescence nanoparticles necessitates ex vivo activation before systemic administration, which prevents long-term imaging in living animals. Here, we introduce a new generation of optical nanoprobes, based on chromium-doped zinc gallate, whose persistent luminescence can be activated in vivo through living tissues using highly penetrating low-energy red photons. Surface functionalization of this photonic probe can be adjusted to favour multiple biomedical applications such as tumour targeting. Notably, we show that cells can endocytose these nanoparticles in vitro and that, after intravenous injection, we can track labelled cells in vivo and follow their biodistribution by a simple whole animal optical detection, opening new perspectives for cell therapy research and for a variety of diagnosis applications.

  15. eNOS3 Genetic Polymorphism Is Related to Post-Ablation Early Recurrence of Atrial Fibrillation

    PubMed Central

    Shim, Jaemin; Park, Jae Hyung; Lee, Ji-Young; Uhm, Jae-Sun; Joung, Boyoung; Lee, Moon-Hyoung; Ellinor, Patrick T.

    2015-01-01

    Purpose Previous studies have demonstrated an association between eNOS polymorphisms and atrial fibrillation (AF). We sought to determine whether eNOS polymorphisms are associated with AF recurrence after a radiofrequency catheter ablation (RFCA). Materials and Methods A total of 500 consecutive patients (56±11 years, 77% male) with paroxysmal (68%) or persistent (32%) AF who underwent RFCA and 500 age, gender-matched controls were genotyped for the eNOS3 single nucleotide polymorphism (rs1799983). AF recurrence was monitored according to 2012 ACC/AHA/ESC guidelines. Results The frequencies of the rs1799983 variant alleles (T) in the case and control group were not significantly different (OR 1.05, 95% CI 0.75-1.46, p=0.798). AF patients with rs1799983 variants were more likely to have coronary artery disease or stroke than those without genetic variant at this gene (31.0% vs. 17.3%, p=0.004). During mean 17 months follow-up, early recurrence of AF (ERAF; within 3 months) and clinical recurrence (CR) of AF were 31.8% and 24.8%, respectively. The rs1799983 variant was associated with higher risk of ERAF (OR 1.71, 95% CI 1.06-2.79, p=0.028), but not with CR. ERAF occurred earlier (11±16 days) in variant group than those without variant allele (20±25 days, p=0.016). A multiple logistic regression analysis showed that presence of the rs1799983 variant (OR 1.75, 95% CI 1.07-2.86, p=0.026) and persistent AF were independent predictors for ERAF after AF ablation. Conclusion The rs1799983 variant of the eNOS3 gene was associated with ERAF, but not with CR, after RFCA. eNOS3 gene variants may have a potential role for stratification of post-ablation management. PMID:26256966

  16. ET-1 Stimulates Superoxide Production by eNOS Following Exposure of Vascular Endothelial Cells to Endotoxin.

    PubMed

    Gopalakrishna, Deepak; Pennington, Samantha; Karaa, Amel; Clemens, Mark G

    2016-07-01

    It has been shown that microcirculation is hypersensitized to endothelin1 (ET-1) following endotoxin (lipopolysaccharide [LPS]) treatment leading to an increased vasopressor response. This may be related in part to decreased activation of endothelial nitric oxide synthase (eNOS) by ET-1. eNOS can also be uncoupled to produce superoxide (O2). This aberrant eNOS activity could further contribute to the hyperconstriction and injury caused by ET-1 following LPS. We therefore tested whether LPS affects ROS production by vascular endothelial cells and whether and how this effect is altered by ET-1. Human umbilical vein endothelial cells (HUVEC) or human microvascular endothelial cells (HMEC) were subjected to a 6-h treatment with LPS (250 ng/mL) or LPS and sepiapterin (100 μM) followed by a 30-min treatment with 100 μM L-Iminoethyl Ornithine (L-NIO) an irreversible eNOS inhibitor and 30-min treatment with ET-1 (10 nM). Conversion of [H]L-arginine to [H]L-citrulline was used to measure eNOS activity. Superoxide dismutase (SOD) inhibitable reduction of Cytochrome-C, dihydro carboxy fluorescein (DCF), and Mitosox was used to estimate ROS. LT-SDS PAGE was used to assess the degree of monomerization of the eNOS homodimer. Stimulation of HUVECs with ET-1 significantly increased NO synthesis by 1.4-fold (P < 0.05). ET-1 stimulation of LPS-treated HUVECs failed to increase NO production. Western blot for eNOS protein showed no change in eNOS protein levels. LPS alone resulted in an insignificant increase in ROS production as measured by cytochrome C that was increased 4.6-fold by ET-1 stimulation (P < 0.05). L-NIO significantly decreased ET-1-induced ROS production (P < 0.05). Sepiapterin significantly decreased ROS production in both; unstimulated and ET-1-stimulated LPS-treated groups, but did not restore NO production. DCF experiments confirmed intracellular ROS while Mitosox suggested a non-mitochondrial source. ET-1 treatment following a chronic LPS stress

  17. Activation of respiratory epithelial cells by wood smoke particles persists beyond immediate exposure.

    EPA Science Inventory

    The biological effect of particles on epithelial cells involves, in part, oxidant generation and a cascade of reactions culminating in inflammatory mediator release. Whether there is an immediate short-lived activation or continued persistent response of the cells to the particle...

  18. Evaluation of the persistence of micropollutants through pure-oxygen activated sludge nitrification and denitrification

    USGS Publications Warehouse

    Levine, A.D.; Meyer, M.T.; Kish, G.

    2006-01-01

    The persistence of pharmaceuticals, hormones, and household and industrial chemicals through a pure-oxygen activated sludge, nitrification, denitrification wastewater treatment facility was evaluated. Of the 125 micropollutants that were tested in this study, 55 compounds were detected in the untreated wastewater, and 27 compounds were detected in the disinfected effluent. The persistent compounds included surfactants, fire-retardant chemicals, pesticides, fragrance compounds, hormones, and one pharmaceutical. Physical-chemical properties of micropollutants that affected partitioning onto wastewater solids included vapor pressure and octanol-water partition coefficients.

  19. Systematic Survey of Serine Hydrolase Activity in Mycobacterium tuberculosis Defines Changes Associated with Persistence.

    PubMed

    Ortega, Corrie; Anderson, Lindsey N; Frando, Andrew; Sadler, Natalie C; Brown, Robert W; Smith, Richard D; Wright, Aaron T; Grundner, Christoph

    2016-02-18

    The transition from replication to non-replication underlies much of Mycobacterium tuberculosis (Mtb) pathogenesis, as non- or slowly replicating Mtb are responsible for persistence and poor treatment outcomes. Therapeutic targeting of non-replicating populations is a priority for tuberculosis treatment, but few drug targets in non-replicating Mtb are currently known. Here, we directly measured the activity of the highly diverse and druggable serine hydrolases (SHs) during active replication and non-replication using activity-based proteomics. We predict SH activity for 78 proteins, including 27 proteins with unknown function, and identify 37 SHs that remain active in the absence of replication, providing a set of candidate persistence targets. Non-replication was associated with major shifts in SH activity. These activity changes were largely independent of SH abundance, indicating extensive post-translational regulation of SHs. By probing a large cross-section of druggable Mtb enzyme space during replication and non-replication, we identify new SHs and suggest new persistence targets. PMID:26853625

  20. Adenosine A2B receptor stimulates angiogenesis by inducing VEGF and eNOS in human microvascular endothelial cells

    PubMed Central

    Du, Xiaolong; Ou, Xuehai; Song, Tao; Zhang, Wentao; Cong, Fei; Zhang, Shihui

    2015-01-01

    Angiogenesis is critical to wound repair due to its role in providing oxygen and nutrients that are required to support the growth and function of reparative cells in damaged tissues. Adenosine receptors are claimed to be of paramount importance in driving wound angiogenesis by inducing VEGF. However, the underlying mechanisms for the regulation of adenosine receptors in VEGF as well as eNOS remain poorly understood. In the present study, we found that adenosine and the non-selective adenosine receptor agonists (NECA) induced tube formation in HMEC-1 in a dose-dependent manner. Adenosine or NECA (10 µmol/L) significantly augmented the number and length of the segments in comparison with the control. Simultaneously, VEGF and eNOS were significantly upregulated following the administration of 10 µmol/L NECA, while they were suppressed after A2B AR genetic silencing and pharmacological inhibition by MRS1754. In addition, VEGF expression and eNOS bioavailability elimination significantly reduced the formation of capillary-like structures. Furthermore, the activation of A2B AR by NECA significantly increased the intracellular cAMP levels and concomitant CREB phosphorylation, eventually leading to the production of VEGF in HMEC-1. However, the activated PKA-CREB pathway seemed to be invalidated in the induction of eNOS. Moreover, we found that the elicited PI3K/AKT signaling in response to the induction of NECA assisted in regulating eNOS but failed to impact on VEGF generation. In conclusion, the A2B AR activation-driven angiogenesis via cAMP-PKA-CREB mediated VEGF production and PI3K/AKT-dependent upregulation of eNOS in HMEC-1. PMID:25966978

  1. eNOS Genetic Polymorphisms and Cancer Risk

    PubMed Central

    Gao, Xueren; Wang, Jie; Wang, Wenjun; Wang, Mingxi; Zhang, Jianqiong

    2015-01-01

    Abstract The association between endothelial nitric oxide synthase (eNOS) polymorphisms (intron 4a/b, -786T>C and 894G>T) and cancer risk remains elusive. In addition, no studies focused on their associations with the risk of breast cancer in Chinese Han population. Thus, a meta-analysis was conducted to determine the relationship between eNOS polymorphisms and cancer risk, and then a case–control study in Chinese Han population was performed to assess their associations with breast cancer susceptibility. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of association. The pooled analysis indicated that eNOS intron 4a/b and -786T>C polymorphisms were significantly associated with an increased risk of overall cancer. In subgroup analyses based on cancer type, the significant association was found between eNOS intron 4a/b polymorphism and prostate cancer risk, eNOS -786T>C polymorphism and risk of prostate, bladder and breast cancers, and eNOS 894G>T polymorphism and breast cancer risk. In subgroup analyses based on ethnicity, eNOS intron 4a/b and -786T>C polymorphisms were associated with an increased risk of cancer in Caucasians. In consistent with our meta-analysis results, a case–control study in Chinese Han population showed significant associations of eNOS -786T>C and 894G>T polymorphisms with the increased risk of breast cancer. In addition, stratified analyses based on pathological type showed that eNOS 894G>T polymorphism was only associated with the risk of infiltrative ductal carcinoma. Stratified analyses by tumor stage showed that eNOS -786T>C polymorphism was only associated with the risk of tumor stage III and IV. In conclusion, our meta-analysis and case–control study suggest that eNOS -786T>C and 894G>T polymorphisms are associated with the increased risk of breast cancer. PMID:26131841

  2. The Nebivolol action on vascular tone is dependent on actin cytoskeleton polymerization and Rho-A activity into ECs and SMCs.

    PubMed

    Kadi, A; de Isla, N; Moby, V; Lacolley, P; Labrude, P; Stoltz, J F; Menu, P

    2014-01-01

    Nitric oxide is implicated in the target action of Nebivolol, a selective β1 adrenoceptor blocker used in hypertension treatment. As the Nitric Oxide (NO) production and the actin cytoskeleton are linked, the aim of this work was to study the involvement of actin cytoskeleton on mechanism of action of Nebivolol in cultured endothelial cells. We studied the effect of Nebivolol (200 μM) on actin filaments remodeling and its impact on NO production and eNOS activation. Results showed that Nebivolol perturbs actin filaments polymerization, increases NO production and eNOS activity between 30 minutes and 1 h. Stabilization of actin filaments with phalloïdine (50 μM) abolishes Nebivolol effects on eNOS activation and NO production. Furthermore, Rho-kinase activity decreased during the first hour of Nebivolol treatment, then increased after 3 h, while actin filaments repolymerized, eNOS activation and NO production decreased. In SMCs, Nebivolol induced a decrease in the Rho-kinase activity from 1 h until 24 h of incubation. In conclusion, we suggest that Nebivolol induced NO production in Endothelial Cells (ECs) via complementary actions between actin cytoskeleton remodeling inducing eNOS activation and Rho-kinase implication. The effect of Nebivolol on ECs occurs during the first hour, this effect on SMCs seems to be maintained until 24 h, explaining persisted action of Nebivolol observed in vivo.

  3. (p)ppGpp controls bacterial persistence by stochastic induction of toxin-antitoxin activity.

    PubMed

    Maisonneuve, Etienne; Castro-Camargo, Manuela; Gerdes, Kenn

    2013-08-29

    Persistence refers to the phenomenon in which isogenic populations of antibiotic-sensitive bacteria produce rare cells that transiently become multidrug tolerant. Whether slow growth in a rare subset of cells underlies the persistence phenotype has not be examined in wild-type bacteria. Here, we show that an exponentially growing population of wild-type Escherichia coli cells produces rare cells that stochastically switch into slow growth, that the slow-growing cells are multidrug tolerant, and that they are able to resuscitate. The persistence phenotype depends hierarchically on the signaling nucleotide (p)ppGpp, Lon protease, inorganic polyphosphate, and toxin-antitoxins. We show that the level of (p)ppGpp varies stochastically in a population of exponentially growing cells and that the high (p)ppGpp level in rare cells induces slow growth and persistence. (p)ppGpp triggers slow growth by activating toxin-antitoxin loci through a regulatory cascade depending on inorganic polyphosphate and Lon protease.

  4. Role of reactive oxygen species in the signalling cascade of cyclosporine A-mediated up-regulation of eNOS in vascular endothelial cells

    PubMed Central

    López-Ongil, S; Hernández-Perera, O; Navarro-Antolín, J; Pérez de Lema, G; Rodríguez-Puyol, M; Lamas, S; Rodríguez-Puyol, D

    1998-01-01

    Cyclosporine A (CsA) increases eNOS mRNA expression in bovine cultured aortic endothelial cells (BAEC). As some effects of CsA may be mediated by reactive oxygen species (ROS), present experiments were devoted to test the hypothesis that the CsA-induced eNOS up-regulation could be dependent on an increased synthesis of ROS.CsA induced a dose-dependent increase of ROS synthesis, with the two fluorescent probes used, DHR123 (CsA 1 μM: 305±7% over control) and H2DCFDA (CsA 1 μM: 178±6% over control).Two ROS generating systems, xanthine plus xanthine oxidase (XXO) and glucose oxidase (GO), increased the expression of eNOS mRNA in BAEC, an effect which was maximal after 8 h of incubation (XXO: 168±21% of control values. GO: 208±18% of control values). The ROS-dependent increased eNOS mRNA expression was followed by an increase in eNOS activity.The effect of CsA on eNOS mRNA expression was abrogated by catalase, and superoxide dismutase (SOD). In contrast, the antioxidant PDTC augmented eNOS mRNA expression, both in basal conditions and in the presence of CsA.The potential participation of the transcription factor AP-1 was explored. Electrophoretic mobility shift assays were consistent with an increase in AP-1 DNA-binding activity in BAEC treated with CsA or glucose oxidase.The present results support a role for ROS, particularly superoxide anion and hydrogen peroxide, as mediators of the CsA-induced eNOS mRNA up-regulation. Furthermore, they situate ROS as potential regulators of gene expression in endothelial cells, both in physiological and pathophysiological situations. PMID:9647467

  5. Identification of Additional Anti-Persister Activity against Borrelia burgdorferi from an FDA Drug Library

    PubMed Central

    Feng, Jie; Weitner, Megan; Shi, Wanliang; Zhang, Shuo; Sullivan, David; Zhang, Ying

    2015-01-01

    Lyme disease is a leading vector-borne disease in the United States. Although the majority of Lyme patients can be cured with standard 2–4 week antibiotic treatment, 10%–20% of patients continue to suffer from prolonged post-treatment Lyme disease syndrome (PTLDS). While the cause for this is unclear, persisting organisms not killed by current Lyme antibiotics may be involved. In our previous study, we screened an FDA drug library and reported 27 top hits that showed high activity against Borrelia persisters. In this study, we present the results of an additional 113 active hits that have higher activity against the stationary phase B. burgdorferi than the currently used Lyme antibiotics. Many antimicrobial agents (antibiotics, antivirals, antifungals, anthelmintics or antiparasitics) used for treating other infections were found to have better activity than the current Lyme antibiotics. These include antibacterials such as rifamycins (3-formal-rifamycin, rifaximin, rifamycin SV), thiostrepton, quinolone drugs (sarafloxacin, clinafloxacin, tosufloxacin), and cell wall inhibitors carbenicillin, tazobactam, aztreonam; antifungal agents such as fluconazole, mepartricin, bifonazole, climbazole, oxiconazole, nystatin; antiviral agents zanamivir, nevirapine, tilorone; antimalarial agents artemisinin, methylene blue, and quidaldine blue; antihelmintic and antiparasitic agents toltrazuril, tartar emetic, potassium antimonyl tartrate trihydrate, oxantel, closantel, hycanthone, pyrimethamine, and tetramisole. Interestingly, drugs used for treating other non-infectious conditions including verteporfin, oltipraz, pyroglutamic acid, pidolic acid, and dextrorphan tartrate, that act on the glutathione/γ-glutamyl pathway involved in protection against free radical damage, and also the antidepressant drug indatraline, were found to have high activity against stationary phase B. burgdorferi. Among the active hits, agents that affect cell membranes, energy production, and

  6. Identification of Additional Anti-Persister Activity against Borrelia burgdorferi from an FDA Drug Library.

    PubMed

    Feng, Jie; Weitner, Megan; Shi, Wanliang; Zhang, Shuo; Sullivan, David; Zhang, Ying

    2015-01-01

    Lyme disease is a leading vector-borne disease in the United States. Although the majority of Lyme patients can be cured with standard 2-4 week antibiotic treatment, 10%-20% of patients continue to suffer from prolonged post-treatment Lyme disease syndrome (PTLDS). While the cause for this is unclear, persisting organisms not killed by current Lyme antibiotics may be involved. In our previous study, we screened an FDA drug library and reported 27 top hits that showed high activity against Borrelia persisters. In this study, we present the results of an additional 113 active hits that have higher activity against the stationary phase B. burgdorferi than the currently used Lyme antibiotics. Many antimicrobial agents (antibiotics, antivirals, antifungals, anthelmintics or antiparasitics) used for treating other infections were found to have better activity than the current Lyme antibiotics. These include antibacterials such as rifamycins (3-formal-rifamycin, rifaximin, rifamycin SV), thiostrepton, quinolone drugs (sarafloxacin, clinafloxacin, tosufloxacin), and cell wall inhibitors carbenicillin, tazobactam, aztreonam; antifungal agents such as fluconazole, mepartricin, bifonazole, climbazole, oxiconazole, nystatin; antiviral agents zanamivir, nevirapine, tilorone; antimalarial agents artemisinin, methylene blue, and quidaldine blue; antihelmintic and antiparasitic agents toltrazuril, tartar emetic, potassium antimonyl tartrate trihydrate, oxantel, closantel, hycanthone, pyrimethamine, and tetramisole. Interestingly, drugs used for treating other non-infectious conditions including verteporfin, oltipraz, pyroglutamic acid, pidolic acid, and dextrorphan tartrate, that act on the glutathione/γ-glutamyl pathway involved in protection against free radical damage, and also the antidepressant drug indatraline, were found to have high activity against stationary phase B. burgdorferi. Among the active hits, agents that affect cell membranes, energy production, and reactive

  7. Recoupling of eNOS with Folic Acid Prevents Abdominal Aortic Aneurysm Formation in Angiotensin II-Infused Apolipoprotein E Null Mice

    PubMed Central

    Siu, Kin Lung; Miao, Xiao Niu; Cai, Hua

    2014-01-01

    We have previously shown that eNOS uncoupling mediates abdominal aortic aneurysm (AAA) formation in hph-1 mice. In the present study we examined whether recoupling of eNOS prevents AAA formation in a well-established model of Angiotensin II-infused apolipoprotein E (apoE) null mice by targeting some common pathologies of AAA. Infusion of Ang II resulted in a 92% incidence rate of AAA in the apoE null animals. In a separate group, animals were treated orally with folic acid (FA), which is known to recouple eNOS through augmentation of dihydrofolate reductase (DHFR) function. This resulted in a reduction of AAA rate to 19.5%. Imaging with ultrasound showed that FA markedly inhibited expansion of abdominal aorta. FA also abolished elastin breakdown and macrophage infiltration in the AAA animals. The eNOS uncoupling activity, assessed by L-NAME-sensitive superoxide production, was minimal at baseline but greatly exaggerated with Ang II infusion, which was completely attenuated by FA. This was accompanied by markedly improved tetrahydrobiopterin and nitric oxide bioavailability. Furthermore, the expression and activity of DHFR was decreased in Ang II-infused apoE null mice specifically in the endothelial cells, while FA administration resulted in its recovery. Taken together, these data further establish a significant role of uncoupled eNOS in mediating AAA formation, and a universal efficacy of FA in preventing AAA formation via restoration of DHFR to restore eNOS function. PMID:24558445

  8. Persistent STAT5 activation in myeloid neoplasms recruits p53 into gene regulation.

    PubMed

    Girardot, M; Pecquet, C; Chachoua, I; Van Hees, J; Guibert, S; Ferrant, A; Knoops, L; Baxter, E J; Beer, P A; Giraudier, S; Moriggl, R; Vainchenker, W; Green, A R; Constantinescu, S N

    2015-03-01

    STAT (Signal Transducer and Activator of Transcription) transcription factors are constitutively activated in most hematopoietic cancers. We previously identified a target gene, LPP/miR-28 (LIM domain containing preferred translocation partner in lipoma), induced by constitutive activation of STAT5, but not by transient cytokine-activated STAT5. miR-28 exerts negative effects on thrombopoietin receptor signaling and platelet formation. Here, we demonstrate that, in transformed hematopoietic cells, STAT5 and p53 must be synergistically bound to chromatin for induction of LPP/miR-28 transcription. Genome-wide association studies show that both STAT5 and p53 are co-localized on the chromatin at 463 genomic positions in proximal promoters. Chromatin binding of p53 is dependent on persistent STAT5 activation at these proximal promoters. The transcriptional activity of selected promoters bound by STAT5 and p53 was significantly changed upon STAT5 or p53 inhibition. Abnormal expression of several STAT5-p53 target genes (LEP, ATP5J, GTF2A2, VEGFC, NPY1R and NPY5R) is frequently detected in platelets of myeloproliferative neoplasm (MPN) patients, but not in platelets from healthy controls. In conclusion, persistently active STAT5 can recruit normal p53, like in the case of MPN cells, but also p53 mutants, such as p53 M133K in human erythroleukemia cells, leading to pathologic gene expression that differs from canonical STAT5 or p53 transcriptional programs.

  9. Immobilized epidermal growth factor stimulates persistent, directed keratinocyte migration via activation of PLCγ1.

    PubMed

    Kim, Chloe S; Mitchell, Isaiah P; Desotell, Anthony W; Kreeger, Pamela K; Masters, Kristyn S

    2016-07-01

    Epidermal growth factor (EGF) is a critical element in dermal repair, but EGF-containing wound dressings have not been successful clinically. However, these dressings have delivered only soluble EGF, and the native environment provides both soluble and matrix-bound EGF. To address our hypothesis that tethered EGF can stimulate cell behaviors not achievable with soluble EGF, we examined single-cell movement and signaling in human immortalized HaCaT keratinocytes treated with soluble or immobilized EGF. Although both EGF treatments increased collective sheet displacement and individual cell speed, only cells treated with immobilized EGF exhibited directed migration, as well as 2-fold greater persistence compared with soluble EGF. Immunofluorescence showed altered EGF receptor (EGFR) trafficking, where EGFR remained membrane-localized in the immobilized EGF condition. Cells treated with soluble EGF demonstrated higher phosphorylated ERK1/2, and cells on immobilized EGF exhibited higher pPLCγ1, which was localized at the leading edge. Treatment with U0126 inhibited migration in both conditions, demonstrating that ERK1/2 activity was necessary but not responsible for the observed differences. In contrast, PLCγ1 inhibition with U73122 significantly decreased persistence on immobilized EGF. Combined, these results suggest that immobilized EGF increases collective keratinocyte displacement via an increase in single-cell migration persistence resulting from altered EGFR trafficking and PLCγ1 activation.-Kim, C. S., Mitchell, I. P., Desotell, A. W., Kreeger, P. K., Masters, K. S. Immobilized epidermal growth factor stimulates persistent, directed keratinocyte migration via activation of PLCγ1.

  10. Immobilized epidermal growth factor stimulates persistent, directed keratinocyte migration via activation of PLCγ1.

    PubMed

    Kim, Chloe S; Mitchell, Isaiah P; Desotell, Anthony W; Kreeger, Pamela K; Masters, Kristyn S

    2016-07-01

    Epidermal growth factor (EGF) is a critical element in dermal repair, but EGF-containing wound dressings have not been successful clinically. However, these dressings have delivered only soluble EGF, and the native environment provides both soluble and matrix-bound EGF. To address our hypothesis that tethered EGF can stimulate cell behaviors not achievable with soluble EGF, we examined single-cell movement and signaling in human immortalized HaCaT keratinocytes treated with soluble or immobilized EGF. Although both EGF treatments increased collective sheet displacement and individual cell speed, only cells treated with immobilized EGF exhibited directed migration, as well as 2-fold greater persistence compared with soluble EGF. Immunofluorescence showed altered EGF receptor (EGFR) trafficking, where EGFR remained membrane-localized in the immobilized EGF condition. Cells treated with soluble EGF demonstrated higher phosphorylated ERK1/2, and cells on immobilized EGF exhibited higher pPLCγ1, which was localized at the leading edge. Treatment with U0126 inhibited migration in both conditions, demonstrating that ERK1/2 activity was necessary but not responsible for the observed differences. In contrast, PLCγ1 inhibition with U73122 significantly decreased persistence on immobilized EGF. Combined, these results suggest that immobilized EGF increases collective keratinocyte displacement via an increase in single-cell migration persistence resulting from altered EGFR trafficking and PLCγ1 activation.-Kim, C. S., Mitchell, I. P., Desotell, A. W., Kreeger, P. K., Masters, K. S. Immobilized epidermal growth factor stimulates persistent, directed keratinocyte migration via activation of PLCγ1. PMID:27025961

  11. Antiphospholipid antibodies promote leukocyte-endothelial cell adhesion and thrombosis in mice by antagonizing eNOS via β2GPI and apoER2.

    PubMed

    Ramesh, Sangeetha; Morrell, Craig N; Tarango, Cristina; Thomas, Gail D; Yuhanna, Ivan S; Girardi, Guillermina; Herz, Joachim; Urbanus, Rolf T; de Groot, Philip G; Thorpe, Philip E; Salmon, Jane E; Shaul, Philip W; Mineo, Chieko

    2011-01-01

    In antiphospholipid syndrome (APS), antiphospholipid antibodies (aPL) binding to β2 glycoprotein I (β2GPI) induce endothelial cell-leukocyte adhesion and thrombus formation via unknown mechanisms. Here we show that in mice both of these processes are caused by the inhibition of eNOS. In studies of cultured human, bovine, and mouse endothelial cells, the promotion of monocyte adhesion by aPL entailed decreased bioavailable NO, and aPL fully antagonized eNOS activation by diverse agonists. Similarly, NO-dependent, acetylcholine-induced increases in carotid vascular conductance were impaired in aPL-treated mice. The inhibition of eNOS was caused by antibody recognition of domain I of β2GPI and β2GPI dimerization, and it was due to attenuated eNOS S1179 phosphorylation mediated by protein phosphatase 2A (PP2A). Furthermore, LDL receptor family member antagonism with receptor-associated protein (RAP) prevented aPL inhibition of eNOS in cell culture, and ApoER2-/- mice were protected from aPL inhibition of eNOS in vivo. Moreover, both aPL-induced increases in leukocyte-endothelial cell adhesion and thrombus formation were absent in eNOS-/- and in ApoER2-/- mice. Thus, aPL-induced leukocyte-endothelial cell adhesion and thrombosis are caused by eNOS antagonism, which is due to impaired S1179 phosphorylation mediated by β2GPI, apoER2, and PP2A. Our results suggest that novel therapies for APS can now be developed targeting these mechanisms. PMID:21123944

  12. Developmental Deltamethrin Exposure Causes Persistent Changes in Dopaminergic Gene Expression, Neurochemistry, and Locomotor Activity in Zebrafish

    PubMed Central

    Kung, Tiffany S.; Richardson, Jason R.; Cooper, Keith R.; White, Lori A.

    2015-01-01

    Pyrethroids are commonly used insecticides that are considered to pose little risk to human health. However, there is an increasing concern that children are more susceptible to the adverse effects of pesticides. We used the zebrafish model to test the hypothesis that developmental exposure to low doses of the pyrethroid deltamethrin results in persistent alterations in dopaminergic gene expression, neurochemistry, and locomotor activity. Zebrafish embryos were treated with deltamethrin (0.25–0.50 μg/l), at concentrations below the LOAEL, during the embryonic period [3–72 h postfertilization (hpf)], after which transferred to fresh water until the larval stage (2-weeks postfertilization). Deltamethrin exposure resulted in decreased transcript levels of the D1 dopamine (DA) receptor (drd1) and increased levels of tyrosine hydroxylase at 72 hpf. The reduction in drd1 transcripts persisted to the larval stage and was associated with decreased D2 dopamine receptor transcripts. Larval fish, exposed developmentally to deltamethrin, had increased levels of homovanillic acid, a DA metabolite. Since the DA system is involved in locomotor activity, we measured the swim activity of larval fish following a transition to darkness. Developmental exposure to deltamethrin significantly increased larval swim activity which was attenuated by concomitant knockdown of the DA transporter. Acute exposure to methylphenidate, a DA transporter inhibitor, increased swim activity in control larva, while reducing swim activity in larva developmentally exposed to deltamethrin. Developmental exposure to deltamethrin causes locomotor deficits in larval zebrafish, which is likely mediated by dopaminergic dysfunction. This highlights the need to understand the persistent effects of low-dose neurotoxicant exposure during development. PMID:25912032

  13. Spatial heterogeneity in human activities favors the persistence of wolves in agroecosystems.

    PubMed

    Ahmadi, Mohsen; López-Bao, José Vicente; Kaboli, Mohammad

    2014-01-01

    As human populations expand, there is increasing demand and pressure for land. Under this scenario, behavioural flexibility and adaptation become important processes leading to the persistence of large carnivores in human-dominated landscapes such as agroecosystems. A growing interest has recently emerged on the outcome of the coexistence between wolves and humans in these systems. It has been suggested that spatial heterogeneity in human activities would be a major environmental factor modulating vulnerability and persistence of this contentious species in agroecosystems. Here, we combined information from 35 den sites detected between 2011 and 2012 in agroecosystems of western Iran (Hamedan province), a set of environmental variables measured at landscape and fine spatial scales, and generalized linear models to identify patterns of den site selection by wolves in a highly-modified agroecosystem. On a landscape level, wolves selected a mixture of rangelands with scattered dry-farms on hillsides (showing a low human use) to locate their dens, avoiding areas with high densities of settlements and primary roads. On a fine spatial scale, wolves primarily excavated dens into the sides of elevated steep-slope hills with availability of water bodies in the vicinity of den sites, and wolves were relegated to dig in places with coarse-soil particles. Our results suggest that vulnerability of wolves in human-dominated landscapes could be compensated by the existence of spatial heterogeneity in human activities. Such heterogeneity would favor wolf persistence in agroecosystems favoring a land sharing model of coexistence between wolves and people.

  14. Ambient ultrafine particles reduce endothelial nitric oxide production via S-glutathionylation of eNOS

    PubMed Central

    Du, Yunfeng; Navab, Mohamad; Shen, Melody; Hill, James; Pakbin, Payam; Sioutas, Constantinos; Hsiai, Tzung; Li, Rongsong

    2013-01-01

    Exposure to airborne particulate pollutants is intimately linked to vascular oxidative stress and inflammatory responses with clinical relevance to atherosclerosis. Particulate matter (PM) has been reported to induce endothelial dysfunction and atherosclerosis. Here, we tested whether ambient ultrafine particles (UFP, diameter < 200 nm) modulate eNOS activity in terms of nitric oxide (NO) production via protein S-glutathionylation. Treatment of human aortic endothelial cells (HAEC) with UFP significantly reduced NO production. UFP-mediated reduction in NO production was restored in the presence of JNK inhibitor (SP600125), NADPH oxidase inhibitor (Apocynin), anti-oxidant (N-acetyl cysteine), and superoxide dismutase mimetics (Tempol and MnTMPyP). UFP exposure increased the GSSG/GSH ratio and eNOS S-glutathionylation, whereas over-expression of Glutaredoxin-1 (to inhibit S-glutathionylation) restored UFP-mediated reduction in NO production by nearly 80%. Thus, our findings suggest that eNOS S-glutathionylation is a potential mechanism underlying ambient UFP-induced reduction of NO production. PMID:23751346

  15. Persistent Activity in Prefrontal Cortex during Trace Eyelid Conditioning: Dissociating Responses That Reflect Cerebellar Output from Those That Do Not

    PubMed Central

    Mauk, Michael D.

    2013-01-01

    Persistent neural activity, responses that outlast the stimuli that evoke them, plays an important role in neural computations and possibly in processes, such as working memory. Recent studies suggest that trace eyelid conditioning, which involves a temporal gap between the conditioned and unconditioned stimuli (the trace interval), requires persistent neural activity in a region of medial prefrontal cortex (mPFC). This persistent activity, which could be conveyed to cerebellum via a pathway through pons, may engage the cerebellum and allow for the expression of conditioned responses. Given the substantial reciprocity observed among many brain regions, it is essential to demonstrate that persistent responses in mPFC neurons are not simply a reflection of cerebellar feedback to the forebrain, leaving open the possibility that such responses could serve as input to the cerebellum. This concern is highlighted by studies showing that hippocampal learning-related activity is abolished by cerebellar inactivation. We inactivated the cerebellum while recording single-unit activity from the mPFC of rabbits trained with a forebrain-dependent trace eyelid conditioning procedure. We report that, whereas the responses of cells that show an onset of increased spike activity during the trace interval were abolished by cerebellar inactivation, persistent responses that begin during the conditioned stimulus and persisted into the trace interval were unaffected. Therefore, conditioned stimulus-evoked persistent responses remain the strongest candidate input pattern to support the cerebellar expression of learned responses. PMID:24048856

  16. Vasoinhibins Prevent Bradykinin-Stimulated Endothelial Cell Proliferation by Inactivating eNOS via Reduction of both Intracellular Ca2+ Levels and eNOS Phosphorylation at Ser1179

    PubMed Central

    Thebault, Stéphanie; González, Carmen; García, Celina; Zamarripa, David Arredondo; Nava, Gabriel; Vaca, Luis; López-Casillas, Fernando; de la Escalera, Gonzalo Martínez; Clapp, Carmen

    2011-01-01

    Vasoinhibins, a family of antiangiogenic peptides derived from prolactin proteolysis, inhibit the vascular effects of several proangiogenic factors, including bradykinin (BK). Here, we report that vasoinhibins block the BK-induced proliferation of bovine umbilical vein endothelial cells. This effect is mediated by the inactivation of endothelial nitric oxide synthase (eNOS), as the NO donor DETA-NONOate reverted vasoinhibin action. It is an experimentally proven fact that the elevation of intracellular Ca2+ levels ([Ca2+]i) upon BK stimulation activates eNOS, and vasoinhibins blocked the BK-mediated activation of phospholipase C and the formation of inositol 1,4,5-triphosphate leading to a reduced release of Ca2+ from intracellular stores. The [Ca2+]i rise evoked by BK also involves the influx of extracellular Ca2+ via canonical transient receptor potential (TRPC) channels. Vasoinhibins likely interfere with TRPC-mediated Ca2+ entry since La3+, which is an enhancer of TRPC4 and TRPC5 channel activity, prevented vasoinhibins from blocking the stimulation by BK of endothelial cell NO production and proliferation, and vasoinhibins reduced the BK-induced increase of TRPC5 mRNA expression. Finally, vasoinhibins prevented the BK-induced phosphorylation of eNOS at Ser1179, a post-translational modification that facilitates Ca2+-calmodulin activation of eNOS. Together, our data show that vasoinhibins, by lowering NO production through the inhibition of both [Ca2+]i mobilization and eNOS phosphorylation, prevent the BK-induced stimulation of endothelial cell proliferation. Thus, vasoinhibins help to regulate BK effects on angiogenesis and vascular homeostasis.

  17. Active control synthesis for flexible space structures excited by persistent disturbances

    NASA Technical Reports Server (NTRS)

    Wie, Bong; Gonzalez, Marcelo

    1990-01-01

    Both classical and state-space synthesis methods for active control of flexible space structures in the presence of persistent disturbances are presented. The methods exploit the so-called internal model principle for asymptotic disturbance rejection. A generic example of flexible space structures is used to illustrate the simplicity of the proposed design methodologies. The concept of a disturbance rejection filter dipole is introduced from a classical control viewpoint. It is shown that the proposed design methods will invariably make use of non-minimum-phase compensation for a class of noncolocated control problems. The need for tradeoffs between performance and parameter robustness is discussed.

  18. Multi-dimensional ENO schemes for general geometries

    NASA Technical Reports Server (NTRS)

    Harten, Ami; Chakravarthy, Sukumar R.

    1991-01-01

    A class of ENO schemes is presented for the numerical solution of multidimensional hyperbolic systems of conservation laws in structured and unstructured grids. This is a class of shock-capturing schemes which are designed to compute cell-averages to high order accuracy. The ENO scheme is composed of a piecewise-polynomial reconstruction of the solution form its given cell-averages, approximate evolution of the resulting initial value problem, and averaging of this approximate solution over each cell. The reconstruction algorithm is based on an adaptive selection of stencil for each cell so as to avoid spurious oscillations near discontinuities while achieving high order of accuracy away from them.

  19. Persistent pain after spinal cord injury is maintained by primary afferent activity.

    PubMed

    Yang, Qing; Wu, Zizhen; Hadden, Julia K; Odem, Max A; Zuo, Yan; Crook, Robyn J; Frost, Jeffrey A; Walters, Edgar T

    2014-08-01

    Chronic pain caused by insults to the CNS (central neuropathic pain) is widely assumed to be maintained exclusively by central mechanisms. However, chronic hyperexcitablility occurs in primary nociceptors after spinal cord injury (SCI), suggesting that SCI pain also depends upon continuing activity of peripheral sensory neurons. The present study in rats (Rattus norvegicus) found persistent upregulation after SCI of protein, but not mRNA, for a voltage-gated Na(+) channel, Nav1.8, that is expressed almost exclusively in primary afferent neurons. Selectively knocking down Nav1.8 after SCI suppressed spontaneous activity in dissociated dorsal root ganglion neurons, reversed hypersensitivity of hindlimb withdrawal reflexes, and reduced ongoing pain assessed by a conditioned place preference test. These results show that activity in primary afferent neurons contributes to ongoing SCI pain. PMID:25100607

  20. CD62L+ NKT cells have prolonged persistence and antitumor activity in vivo

    PubMed Central

    Tian, Gengwen; Courtney, Amy N.; Jena, Bipulendu; Heczey, Andras; Liu, Daofeng; Marinova, Ekaterina; Guo, Linjie; Xu, Xin; Torikai, Hiroki; Mo, Qianxing; Dotti, Gianpietro; Cooper, Laurence J.; Metelitsa, Leonid S.

    2016-01-01

    Vα24-invariant natural killer T cells (NKTs) localize to tumors and have inherent antitumor properties, making them attractive chimeric antigen receptor (CAR) carriers for redirected cancer immunotherapy. However, clinical application of CAR-NKTs has been impeded, as mechanisms responsible for NKT expansion and the in vivo persistence of these cells are unknown. Here, we demonstrated that antigen-induced expansion of primary NKTs in vitro associates with the accumulation of a CD62L+ subset and exhaustion of CD62L– cells. Only CD62L+ NKTs survived and proliferated in response to secondary stimulation. When transferred to immune-deficient NSG mice, CD62L+ NKTs persisted 5 times longer than CD62L– NKTs. Moreover, CD62L+ cells transduced with a CD19-specific CAR achieved sustained tumor regression in a B cell lymphoma model. Proliferating CD62L+ cells downregulated or maintained CD62L expression when activated via T cell receptor alone or in combination with costimulatory receptors. We generated HLAnull K562 cell clones that were engineered to express CD1d and costimulatory ligands. Clone B-8-2 (HLAnullCD1dmedCD86high4-1BBLmedOX40Lhigh) induced the highest rates of NKT expansion and CD62L expression. B-8-2–expanded CAR-NKTs exhibited prolonged in vivo persistence and superior therapeutic activities in models of lymphoma and neuroblastoma. Therefore, we have identified CD62L as a marker of a distinct NKT subset endowed with high proliferative potential and have developed artificial antigen-presenting cells that generate CD62L-enriched NKTs for effective cancer immunotherapy. PMID:27183388

  1. CD62L+ NKT cells have prolonged persistence and antitumor activity in vivo.

    PubMed

    Tian, Gengwen; Courtney, Amy N; Jena, Bipulendu; Heczey, Andras; Liu, Daofeng; Marinova, Ekaterina; Guo, Linjie; Xu, Xin; Torikai, Hiroki; Mo, Qianxing; Dotti, Gianpietro; Cooper, Laurence J; Metelitsa, Leonid S

    2016-06-01

    Vα24-invariant natural killer T cells (NKTs) localize to tumors and have inherent antitumor properties, making them attractive chimeric antigen receptor (CAR) carriers for redirected cancer immunotherapy. However, clinical application of CAR-NKTs has been impeded, as mechanisms responsible for NKT expansion and the in vivo persistence of these cells are unknown. Here, we demonstrated that antigen-induced expansion of primary NKTs in vitro associates with the accumulation of a CD62L+ subset and exhaustion of CD62L- cells. Only CD62L+ NKTs survived and proliferated in response to secondary stimulation. When transferred to immune-deficient NSG mice, CD62L+ NKTs persisted 5 times longer than CD62L- NKTs. Moreover, CD62L+ cells transduced with a CD19-specific CAR achieved sustained tumor regression in a B cell lymphoma model. Proliferating CD62L+ cells downregulated or maintained CD62L expression when activated via T cell receptor alone or in combination with costimulatory receptors. We generated HLAnull K562 cell clones that were engineered to express CD1d and costimulatory ligands. Clone B-8-2 (HLAnullCD1dmedCD86high4-1BBLmedOX40Lhigh) induced the highest rates of NKT expansion and CD62L expression. B-8-2-expanded CAR-NKTs exhibited prolonged in vivo persistence and superior therapeutic activities in models of lymphoma and neuroblastoma. Therefore, we have identified CD62L as a marker of a distinct NKT subset endowed with high proliferative potential and have developed artificial antigen-presenting cells that generate CD62L-enriched NKTs for effective cancer immunotherapy.

  2. CD62L+ NKT cells have prolonged persistence and antitumor activity in vivo.

    PubMed

    Tian, Gengwen; Courtney, Amy N; Jena, Bipulendu; Heczey, Andras; Liu, Daofeng; Marinova, Ekaterina; Guo, Linjie; Xu, Xin; Torikai, Hiroki; Mo, Qianxing; Dotti, Gianpietro; Cooper, Laurence J; Metelitsa, Leonid S

    2016-06-01

    Vα24-invariant natural killer T cells (NKTs) localize to tumors and have inherent antitumor properties, making them attractive chimeric antigen receptor (CAR) carriers for redirected cancer immunotherapy. However, clinical application of CAR-NKTs has been impeded, as mechanisms responsible for NKT expansion and the in vivo persistence of these cells are unknown. Here, we demonstrated that antigen-induced expansion of primary NKTs in vitro associates with the accumulation of a CD62L+ subset and exhaustion of CD62L- cells. Only CD62L+ NKTs survived and proliferated in response to secondary stimulation. When transferred to immune-deficient NSG mice, CD62L+ NKTs persisted 5 times longer than CD62L- NKTs. Moreover, CD62L+ cells transduced with a CD19-specific CAR achieved sustained tumor regression in a B cell lymphoma model. Proliferating CD62L+ cells downregulated or maintained CD62L expression when activated via T cell receptor alone or in combination with costimulatory receptors. We generated HLAnull K562 cell clones that were engineered to express CD1d and costimulatory ligands. Clone B-8-2 (HLAnullCD1dmedCD86high4-1BBLmedOX40Lhigh) induced the highest rates of NKT expansion and CD62L expression. B-8-2-expanded CAR-NKTs exhibited prolonged in vivo persistence and superior therapeutic activities in models of lymphoma and neuroblastoma. Therefore, we have identified CD62L as a marker of a distinct NKT subset endowed with high proliferative potential and have developed artificial antigen-presenting cells that generate CD62L-enriched NKTs for effective cancer immunotherapy. PMID:27183388

  3. Activation of persistent Streptococcus equi subspecies zooepidemicus in mares with subclinical endometritis.

    PubMed

    Petersen, M R; Skive, B; Christoffersen, M; Lu, K; Nielsen, J M; Troedsson, M H T; Bojesen, A M

    2015-08-31

    Endometritis in horses caused by Streptococcus equi subspecies zooepidemicus (S. zooepidemicus) may be underdiagnosed due to traditional diagnostic methods lacking sensitivity and specificity. We serendipitously identified a bacterial growth medium (bActivate) that appeared capable of inducing growth of dormant S. zooepidemicus, which subsequently allowed detection by standard diagnostics. To assess the effect of bActivate we compared its ability to activate dormant S. zooepidemicus in a group of potentially infected subfertile mares with phosphate-buffered saline (PBS). All mares had to test negative for S. zooepidemicus on a low-volume uterine lavage, be negative on endometrial cytology and without clinical signs of endometritis to be included in the investigation. The mares were instilled with bActivate or PBS in the uterus. Growth of S. zooepidemicus was induced by bActivate in 64% (16/25) and PBS in 8% (1/12) of the mares, respectively (p<0.002). In vitro studies supported that some strains of S. zooepidemicus were able to form persister cells tolerating 32-times of the minimal inhibitory concentration of penicillin compared to normal growing cells. Persister cells had not acquired penicillin resistance, but seemed to tolerate the antimicrobial due to dormancy. This is, to our knowledge, the first description of controlled growth induction of dormant bacteria from a subclinical infection. Moreover we demonstrated how endometritis can origin from a reservoir of dormant bacteria residing within the endometrium, and not only as an ascending infection. Further studies should aim at determining the prevalence of dormant S. zooepidemicus, impact of activation on diagnostic and treatment efficacy, uterine health and mare fertility. PMID:26123371

  4. Correlations in background activity control persistent state stability and allow execution of working memory tasks

    PubMed Central

    Dipoppa, Mario; Gutkin, Boris S.

    2013-01-01

    Working memory (WM) requires selective information gating, active information maintenance, and rapid active updating. Hence performing a WM task needs rapid and controlled transitions between neural persistent activity and the resting state. We propose that changes in correlations in neural activity provides a mechanism for the required WM operations. As a proof of principle, we implement sustained activity and WM in recurrently coupled spiking networks with neurons receiving excitatory random background activity where background correlations are induced by a common noise source. We first characterize how the level of background correlations controls the stability of the persistent state. With sufficiently high correlations, the sustained state becomes practically unstable, so it cannot be initiated by a transient stimulus. We exploit this in WM models implementing the delay match to sample task by modulating flexibly in time the correlation level at different phases of the task. The modulation sets the network in different working regimes: more prompt to gate in a signal or clear the memory. We examine how the correlations affect the ability of the network to perform the task when distractors are present. We show that in a winner-take-all version of the model, where two populations cross-inhibit, correlations make the distractor blocking robust. In a version of the mode where no cross inhibition is present, we show that appropriate modulation of correlation levels is sufficient to also block the distractor access while leaving the relevant memory trace in tact. The findings presented in this manuscript can form the basis for a new paradigm about how correlations are flexibly controlled by the cortical circuits to execute WM operations. PMID:24155714

  5. Comparative immunoprophylactic efficacy of Haemonchus contortus recombinant enolase (rHcENO) and Con A purified native glycoproteins in sheep.

    PubMed

    Kalyanasundaram, Aravindan; Jawahar, Shabnam; Ilangopathy, Manikkavasagan; Palavesam, Azahahianambi; Raman, Muthusamy

    2015-07-01

    Haemonchus contortus is the most economically important blood feeding nematode parasite of sheep and goats all over the world. Enolase in helminth parasites is a multi-functional enzyme which involves in glycolysis and host tissue invasion. In this study, the recombinant H. contortus enolase (rHcENO) was evaluated for its immunoprophylactic efficacy in sheep along with Con A purified native glycoproteins in a vaccine challenge trial. Group I and Group II experimental sheep were immunized thrice with rHcENO and Con A purified native glycoproteins along with Montanide ISA 61 VG adjuvant. The animals were challenged with 5000 L3 stage active H. contortus larvae after 21 days of third immunization. A significant increase in the IgG titre was observed in rHcENO and Con A purified native glycoproteins immunized animals as compared to the control animals. Immunoprotective efficacy of Con A purified native glycoproteins was comparatively higher than rHcENO antigen.

  6. Dendritic Nonlinearities Reduce Network Size Requirements and Mediate ON and OFF States of Persistent Activity in a PFC Microcircuit Model

    PubMed Central

    Papoutsi, Athanasia; Sidiropoulou, Kyriaki; Poirazi, Panayiota

    2014-01-01

    Technological advances have unraveled the existence of small clusters of co-active neurons in the neocortex. The functional implications of these microcircuits are in large part unexplored. Using a heavily constrained biophysical model of a L5 PFC microcircuit, we recently showed that these structures act as tunable modules of persistent activity, the cellular correlate of working memory. Here, we investigate the mechanisms that underlie persistent activity emergence (ON) and termination (OFF) and search for the minimum network size required for expressing these states within physiological regimes. We show that (a) NMDA-mediated dendritic spikes gate the induction of persistent firing in the microcircuit. (b) The minimum network size required for persistent activity induction is inversely proportional to the synaptic drive of each excitatory neuron. (c) Relaxation of connectivity and synaptic delay constraints eliminates the gating effect of NMDA spikes, albeit at a cost of much larger networks. (d) Persistent activity termination by increased inhibition depends on the strength of the synaptic input and is negatively modulated by dADP. (e) Slow synaptic mechanisms and network activity contain predictive information regarding the ability of a given stimulus to turn ON and/or OFF persistent firing in the microcircuit model. Overall, this study zooms out from dendrites to cell assemblies and suggests a tight interaction between dendritic non-linearities and network properties (size/connectivity) that may facilitate the short-memory function of the PFC. PMID:25077940

  7. Ramping ensemble activity in dorsal anterior cingulate neurons during persistent commitment to a decision.

    PubMed

    Blanchard, Tommy C; Strait, Caleb E; Hayden, Benjamin Y

    2015-10-01

    We frequently need to commit to a choice to achieve our goals; however, the neural processes that keep us motivated in pursuit of delayed goals remain obscure. We examined ensemble responses of neurons in macaque dorsal anterior cingulate cortex (dACC), an area previously implicated in self-control and persistence, in a task that requires commitment to a choice to obtain a reward. After reward receipt, dACC neurons signaled reward amount with characteristic ensemble firing rate patterns; during the delay in anticipation of the reward, ensemble activity smoothly and gradually came to resemble the postreward pattern. On the subset of risky trials, in which a reward was anticipated with 50% certainty, ramping ensemble activity evolved to the pattern associated with the anticipated reward (and not with the anticipated loss) and then, on loss trials, took on an inverted form anticorrelated with the form associated with a win. These findings enrich our knowledge of reward processing in dACC and may have broader implications for our understanding of persistence and self-control. PMID:26334016

  8. Norflurazon mobility, dissipation, activity, and persistence in a sandy soil as influenced by formulation.

    PubMed

    Sopeña, Fátima; Maqueda, Celia; Morillo, Esmeralda

    2007-05-01

    Five ethylcellulose (EC) microencapsulated formulations (MEFs) of norflurazon were prepared and applied in soil to study their mobility, dissipation, activity, and persistence. The results show that the release into water of norflurazon from EC microspheres was retarded when compared with that of commercial herbicide. The mobility of norflurazon from MEFs into soil columns has been greatly diminished in comparison with that of its current commercial formulation (CF). Norflurazon distribution at different depths in the soil was higher in the upper ring (up to 50% of the initial application). In contrast, the residues from commercial norflurazon along the complete soil column were only about 2%. Degradation and bioassay experiments showed that the MEFs had greater persistence (t1/2 values were 7.72 and 30.83 weeks for CF and MEFs, respectively) and herbicidal activity than the commercial formulation. The use of these formulations can be advantageous, because they can minimize the risk of groundwater contamination and permit herbicide use at reduced rates, maintaining the desired concentrations of herbicide in the topsoil layer for longer periods of weed control.

  9. Maternal eNOS deficiency determines a fatty liver phenotype of the offspring in a sex dependent manner

    PubMed Central

    Hocher, Berthold; Haumann, Hannah; Rahnenführer, Jan; Reichetzeder, Christoph; Kalk, Philipp; Pfab, Thiemo; Tsuprykov, Oleg; Winter, Stefan; Hofmann, Ute; Li, Jian; Püschel, Gerhard P.; Lang, Florian; Schuppan, Detlef; Schwab, Matthias; Schaeffeler, Elke

    2016-01-01

    ABSTRACT Maternal environmental factors can impact on the phenotype of the offspring via the induction of epigenetic adaptive mechanisms. The advanced fetal programming hypothesis proposes that maternal genetic variants may influence the offspring's phenotype indirectly via epigenetic modification, despite the absence of a primary genetic defect. To test this hypothesis, heterozygous female eNOS knockout mice and wild type mice were bred with male wild type mice. We then assessed the impact of maternal eNOS deficiency on the liver phenotype of wild type offspring. Birth weight of male wild type offspring born to female heterozygous eNOS knockout mice was reduced compared to offspring of wild type mice. Moreover, the offspring displayed a sex specific liver phenotype, with an increased liver weight, due to steatosis. This was accompanied by sex specific differences in expression and DNA methylation of distinct genes. Liver global DNA methylation was significantly enhanced in both male and female offspring. Also, hepatic parameters of carbohydrate metabolism were reduced in male and female offspring. In addition, male mice displayed reductions in various amino acids in the liver. Maternal genetic alterations, such as partial deletion of the eNOS gene, can affect liver metabolism of wild type offspring without transmission of the intrinsic defect. This occurs in a sex specific way, with more detrimental effects in females. This finding demonstrates that a maternal genetic defect can epigenetically alter the phenotype of the offspring, without inheritance of the defect itself. Importantly, these acquired epigenetic phenotypic changes can persist into adulthood. PMID:27175980

  10. Lactase persistence DNA variant enhances lactase promoter activity in vitro: functional role as a cis regulatory element.

    PubMed

    Olds, Lynne C; Sibley, Eric

    2003-09-15

    Lactase persistence is a heritable, autosomal dominant, condition that results in a sustained ability to digest the milk sugar lactose throughout adulthood. The majority of the world's human population experiences a decline in production of the digestive enzyme lactase-phlorizin hydrolase during maturation. However, individuals with lactase persistence continue to express high levels of the lactase gene into adulthood. Lactase persistence has been strongly correlated with single nucleotide genetic variants, C/T_(13910) and G/A_(22018), located 13.9 and 22 kb upstream from the lactase structural gene. We aimed to characterize a functional role for the polymorphisms in regulating lactase gene transcription. DNA in the region of the C/T_(13910) or G/A_(22018) human lactase variants was cloned upstream of the 3.0 kb rat lactase gene promoter in a luciferase reporter construct. Human intestinal Caco-2 cells were transfected with the lactase variant/promoter-reporter constructs and assayed for promoter activity. A 200 bp region surrounding the C_(13910) variant, associated with lactase non-persistence, results in a 2.2-fold increase in lactase promoter activity. The T_(13910) variant, associated with lactase persistence, results in an even greater 2.8-fold increase. The DNA sequence of the C/T_(13910) variants differentially interacts with intestinal cell nuclear proteins on EMSAs. AP2 co-transfection results in a similar repression of the C/T_(13910) variant/promoter-reporter constructs. The DNA region of the C/T_(13910) lactase persistence/non-persistence variant functions in vitro as a cis element capable of enhancing differential transcriptional activation of the lactase promoter. Such differential regulation by the C and T variants is consistent with a causative role in the mechanism specifying the lactase persistence/non-persistence phenotypes in humans.

  11. Theodore E. Woodward Award: lactase persistence SNPs in African populations regulate promoter activity in intestinal cell culture.

    PubMed

    Sibley, Eric; Ahn, Jong Kun

    2011-01-01

    Lactase-phlorizin hydrolase, lactase, is the intestinal enzyme responsible for the digestion of the milk sugar lactose. The majority of the world's human population experiences a decline in expression of the lactase gene by late childhood (lactase non-persistence). Individuals with lactase persistence, however, continue to express high levels of the lactase gene throughout adulthood. Lactase persistence is a heritable autosomal dominant condition and has been strongly correlated with several single nucleotide polymorphisms (SNPs) located ∼14 kb upstream of the lactase gene in different ethnic populations: -13910*T in Europeans and -13907*G, -13915*G, and -14010*C in several African populations. The coincidence of the four SNPs clustering within 100 bp strongly suggests that this region mediates the lactase non-persistence/persistence phenotype. Having previously characterized the European SNP, we aimed to determine whether the African SNPs similarly mediate a functional role in regulating the lactase promoter. Human intestinal Caco-2 cells were transfected with lactase SNP/promoter-reporter constructs and assayed for promoter activity. The -13907*G and -13915*G SNPs result in a significant enhancement of lactase promoter activity relative to the ancestral lactase non-persistence genotype. Such differential regulation by the SNPs is consistent with a causative role in the mechanism specifying the lactase persistence phenotype.

  12. Voltage-gated Na+ Channel Activity Increases Colon Cancer Transcriptional Activity and Invasion Via Persistent MAPK Signaling

    PubMed Central

    House, Carrie D.; Wang, Bi-Dar; Ceniccola, Kristin; Williams, Russell; Simaan, May; Olender, Jacqueline; Patel, Vyomesh; Baptista-Hon, Daniel T.; Annunziata, Christina M.; Silvio Gutkind, J.; Hales, Tim G.; Lee, Norman H.

    2015-01-01

    Functional expression of voltage-gated Na+ channels (VGSCs) has been demonstrated in multiple cancer cell types where channel activity induces invasive activity. The signaling mechanisms by which VGSCs promote oncogenesis remain poorly understood. We explored the signal transduction process critical to VGSC-mediated invasion on the basis of reports linking channel activity to gene expression changes in excitable cells. Coincidentally, many genes transcriptionally regulated by the SCN5A isoform in colon cancer have an over-representation of cis-acting sites for transcription factors phosphorylated by ERK1/2 MAPK. We hypothesized that VGSC activity promotes MAPK activation to induce transcriptional changes in invasion-related genes. Using pharmacological inhibitors/activators and siRNA-mediated gene knockdowns, we correlated channel activity with Rap1-dependent persistent MAPK activation in the SW620 human colon cancer cell line. We further demonstrated that VGSC activity induces downstream changes in invasion-related gene expression via a PKA/ERK/c-JUN/ELK-1/ETS-1 transcriptional pathway. This is the first study illustrating a molecular mechanism linking functional activity of VGSCs to transcriptional activation of invasion-related genes. PMID:26096612

  13. Voltage-gated Na+ Channel Activity Increases Colon Cancer Transcriptional Activity and Invasion Via Persistent MAPK Signaling

    NASA Astrophysics Data System (ADS)

    House, Carrie D.; Wang, Bi-Dar; Ceniccola, Kristin; Williams, Russell; Simaan, May; Olender, Jacqueline; Patel, Vyomesh; Baptista-Hon, Daniel T.; Annunziata, Christina M.; Silvio Gutkind, J.; Hales, Tim G.; Lee, Norman H.

    2015-06-01

    Functional expression of voltage-gated Na+ channels (VGSCs) has been demonstrated in multiple cancer cell types where channel activity induces invasive activity. The signaling mechanisms by which VGSCs promote oncogenesis remain poorly understood. We explored the signal transduction process critical to VGSC-mediated invasion on the basis of reports linking channel activity to gene expression changes in excitable cells. Coincidentally, many genes transcriptionally regulated by the SCN5A isoform in colon cancer have an over-representation of cis-acting sites for transcription factors phosphorylated by ERK1/2 MAPK. We hypothesized that VGSC activity promotes MAPK activation to induce transcriptional changes in invasion-related genes. Using pharmacological inhibitors/activators and siRNA-mediated gene knockdowns, we correlated channel activity with Rap1-dependent persistent MAPK activation in the SW620 human colon cancer cell line. We further demonstrated that VGSC activity induces downstream changes in invasion-related gene expression via a PKA/ERK/c-JUN/ELK-1/ETS-1 transcriptional pathway. This is the first study illustrating a molecular mechanism linking functional activity of VGSCs to transcriptional activation of invasion-related genes.

  14. Biodegradation of persistent organics can overcome adsorption-desorption hysteresis in biological activated carbon systems.

    PubMed

    Abromaitis, V; Racys, V; van der Marel, P; Meulepas, R J W

    2016-04-01

    In Biological Activated Carbon (BAC) systems, persistent organic pollutants can be removed through a combination of adsorption, desorption and biodegradation. These processes might be affected by the presence of other organics, especially by the more abundant easily-biodegradable organics, like acetate. In this research these relations are quantified for the removal of the persistent pharmaceutical metoprolol. Acetate did not affect the adsorption and desorption of metoprolol, but it did greatly enhance the metoprolol biodegradation. At least part of the BAC biomass growing on acetate was also able to metabolise metoprolol, although metoprolol was only converted after the acetate was depleted. The presence of easily-degradable organics like acetate in the feeding water is therefore beneficial for the removal of metoprolol in BAC systems. The isotherms obtained from metoprolol adsorption and desorption experiments showed that BAC systems are subject to hysteresis; for AC bioregeneration to take place the microbial biomass has to reduce the concentration at the AC-biomass interface 2.7 times compared to the concentration at which the carbon was being loaded. However, given the threshold concentration of the MET degrading microorganisms (<0.08 μg/L) versus the average influent concentration (1.3 μg/L), bioregeneration is feasible.

  15. DUOX1 mediates persistent epithelial EGFR activation, mucous cell metaplasia, and airway remodeling during allergic asthma

    PubMed Central

    Habibovic, Aida; Hristova, Milena; Heppner, David E.; Danyal, Karamatullah; Ather, Jennifer L.; Janssen-Heininger, Yvonne M.W.; Irvin, Charles G.; Poynter, Matthew E.; Lundblad, Lennart K.; Dixon, Anne E.; Geiszt, Miklos

    2016-01-01

    Chronic inflammation with mucous metaplasia and airway remodeling are hallmarks of allergic asthma, and these outcomes have been associated with enhanced expression and activation of EGFR signaling. Here, we demonstrate enhanced expression of EGFR ligands such as amphiregulin as well as constitutive EGFR activation in cultured nasal epithelial cells from asthmatic subjects compared with nonasthmatic controls and in lung tissues of mice during house dust mite–induced (HDM-induced) allergic inflammation. EGFR activation was associated with cysteine oxidation within EGFR and the nonreceptor tyrosine kinase Src, and both amphiregulin production and oxidative EGFR activation were diminished by pharmacologic or genetic inhibition of the epithelial NADPH oxidase dual oxidase 1 (DUOX1). DUOX1 deficiency also attenuated several EGFR-dependent features of HDM-induced allergic airway inflammation, including neutrophilic inflammation, type 2 cytokine production (IL-33, IL-13), mucous metaplasia, subepithelial fibrosis, and central airway resistance. Moreover, targeted inhibition of airway DUOX1 in mice with previously established HDM-induced allergic inflammation, by intratracheal administration of DUOX1-targeted siRNA or pharmacological NADPH oxidase inhibitors, reversed most of these outcomes. Our findings indicate an important function for DUOX1 in allergic inflammation related to persistent EGFR activation and suggest that DUOX1 targeting may represent an attractive strategy in asthma management. PMID:27812543

  16. Persistent activity in a cortical-to-subcortical circuit: bridging the temporal gap in trace eyelid conditioning

    PubMed Central

    Kalmbach, Brian; Chitwood, Raymond A.; Mauk, Michael D.

    2012-01-01

    We have addressed the source and nature of the persistent neural activity that bridges the stimulus-free gap between the conditioned stimulus (CS) and unconditioned stimulus (US) during trace eyelid conditioning. Previous work has demonstrated that this persistent activity is necessary for trace eyelid conditioning: CS-elicited activity in mossy fiber inputs to the cerebellum does not extend into the stimulus-free trace interval, which precludes the cerebellar learning that mediates conditioned response expression. In behaving rabbits we used in vivo recordings from a region of medial prefrontal cortex (mPFC) that is necessary for trace eyelid conditioning to test the hypothesis that neurons there generate activity that persists beyond CS offset. These recordings revealed two patterns of activity during the trace interval that would enable cerebellar learning. Activity in some cells began during the tone CS and persisted to overlap with the US, whereas in other cells, activity began during the stimulus-free trace interval. Injection of anterograde tracers into this same region of mPFC revealed dense labeling in the pontine nuclei, where recordings also revealed tone-evoked persistent activity during trace conditioning. These data suggest a corticopontine pathway that provides an input to the cerebellum during trace conditioning trials that bridges the temporal gap between the CS and US to engage cerebellar learning. As such, trace eyelid conditioning represents a well-characterized and experimentally tractable system that can facilitate mechanistic analyses of cortical persistent activity and how it is used by downstream brain structures to influence behavior. PMID:21957220

  17. Manipulation of persistent free radicals in biochar to activate persulfate for contaminant degradation.

    PubMed

    Fang, Guodong; Liu, Cun; Gao, Juan; Dionysiou, Dionysios D; Zhou, Dongmei

    2015-05-01

    This study investigated the effects of metals (Fe3+, Cu2+, Ni2+, and Zn2+) and phenolic compounds (PCs: hydroquinone, catechol, and phenol) loaded on biomass on the formation of persistent free radicals (PFRs) in biochar. It was found that metal and phenolic compound treatments not only increased the concentrations of PFRs in biochar but also changed the types of PFRs formed, which indicated that manipulating the amount of metals and PCs in biomass may be an efficient method to regulate PFRs in biochar. These results provided direct evidence to elucidate the mechanism of PFR formation in biochar. Furthermore, the catalytic ability of biochar toward persulfate activation for the degradation of contaminants was evaluated. The results indicated that biochar activates persulfate to produce sulfate radicals (SO4•-) and degraded polychlorinated biphenyls (PCBs) efficiently. It was found that both the concentration and type of PFRs were the dominant factors controlling the activation of persulfate by biochar and that superoxide radical anions account for 20-30% of sulfate radical generation in biochar/persulfate. This conclusion was supported by linear correlations between the concentration of PFRs consumed and the formation of SO4•- and between λ (λ=[formed sulfate radicals]/[consumed PFRs]) and g-factors. The findings of this study provide new methods to manipulate PFR concentration in biochar for the transformation of contaminants and development of new alternative activators for persulfate-based remediation of contaminated soils.

  18. Endogenous adenosine A3 receptor activation selectively alleviates persistent pain states.

    PubMed

    Little, Joshua W; Ford, Amanda; Symons-Liguori, Ashley M; Chen, Zhoumou; Janes, Kali; Doyle, Timothy; Xie, Jennifer; Luongo, Livio; Tosh, Dillip K; Maione, Sabatino; Bannister, Kirsty; Dickenson, Anthony H; Vanderah, Todd W; Porreca, Frank; Jacobson, Kenneth A; Salvemini, Daniela

    2015-01-01

    Chronic pain is a global burden that promotes disability and unnecessary suffering. To date, efficacious treatment of chronic pain has not been achieved. Thus, new therapeutic targets are needed. Here, we demonstrate that increasing endogenous adenosine levels through selective adenosine kinase inhibition produces powerful analgesic effects in rodent models of experimental neuropathic pain through the A3 adenosine receptor (A3AR, now known as ADORA3) signalling pathway. Similar results were obtained by the administration of a novel and highly selective A3AR agonist. These effects were prevented by blockade of spinal and supraspinal A3AR, lost in A3AR knock-out mice, and independent of opioid and endocannabinoid mechanisms. A3AR activation also relieved non-evoked spontaneous pain behaviours without promoting analgesic tolerance or inherent reward. Further examination revealed that A3AR activation reduced spinal cord pain processing by decreasing the excitability of spinal wide dynamic range neurons and producing supraspinal inhibition of spinal nociception through activation of serotonergic and noradrenergic bulbospinal circuits. Critically, engaging the A3AR mechanism did not alter nociceptive thresholds in non-neuropathy animals and therefore produced selective alleviation of persistent neuropathic pain states. These studies reveal A3AR activation by adenosine as an endogenous anti-nociceptive pathway and support the development of A3AR agonists as novel therapeutics to treat chronic pain. PMID:25414036

  19. PECAM-1 Isoforms, eNOS, and Endoglin Axis in Regulation of Angiogenesis

    PubMed Central

    Park, SunYoung; Sorenson, Christine M.; Sheibani, Nader

    2016-01-01

    Vascular development and maintenance of proper vascular function through various regulatory mechanisms are critical to our wellbeing. Delineating the regulatory processes involved in development of vascular system and function is one of the most important topics in human physiology and pathophysiology. Platelet endothelial cell adhesion molecule-1 (PECAM-1/CD31), a cell adhesion molecule with proangiogenic and proinflammatory activity, has been subject of numerous studies. Here we will review the important roles PECAM-1 and its isoforms play during angiogenesis, and its molecular mechanisms of action in the endothelium. In the endothelium, PECAM-1 not only plays a role as an adhesion molecule but also participates in intracellular signaling pathways which impact various cell adhesive mechanisms and endothelial nitric oxide (eNOS) expression and activity. In addition, recent studies from our laboratory have revealed an important relationship between PECAM-1 and endoglin expression. Endoglin is an essential molecule during angiogenesis, vascular development and integrity whose expression and activity are compromised in the absence of PECAM-1. Here we will discuss the roles PECAM-1 isoforms may play in modulation of endothelial cell adhesive mechanisms, eNOS and endoglin expression and activity, and angiogenesis. PMID:25976664

  20. Ephrin-A1 Is Up-Regulated by Hypoxia in Cancer Cells and Promotes Angiogenesis of HUVECs through a Coordinated Cross-Talk with eNOS

    PubMed Central

    Song, Kai; Shang, Zheng-Jun

    2013-01-01

    Hypoxia, ephrin-A1 and endothelial nitric oxide synthase (eNOS) have been proved to play critical roles in tumor angiogenesis. However, how ephrin-A1 is regulated by hypoxia and whether ephrin-A1 cooperates with eNOS in modulation of angiogenesis remain to be addressed in details. Here we demonstrated that both ephrin-A1 in squamous cell carcinoma cells (SCC-9) and especially soluble ephrin-A1 in the supernatants were up-regulated under hypoxic condition. An increased nitric oxide (NO) production in human umbilical vein endothelial cells (HUVECs) was observed in ephrin-A1-induced angiogenesis which was reversed after co-culture with eNOS specific inhibitor, N-nitro-L-arginine methyl ester hydrochloride (L-NAME). Western blot analysis confirmed that both phosphorylation of AktSer473 and eNOSSer1177 were up-regulated in ephrin-A1-stimulated HUVECs, with the total eNOS expression unchanged. The specific inhibitor of phosphatidylinositol 3-kinase (PI3K), LY294002, significantly down-regulated ephrin-A1-induced expression of phosphorylated AktSer473 as well as phosphorylation of eNOSSer1177. These results revealed a possible novel mechanism whereby ephrin-A1 is regulated in tumor microenvironment and promotes angiogenesis through a coordinated cross-talk with PI3K/Akt-dependent eNOS activation which may relate to normal vascular development and tumor neovascularization. PMID:24040255

  1. SO2 emissions from persistently active explosive volcanoes: can we estimate their contribution using satellite instruments?

    NASA Astrophysics Data System (ADS)

    Smekens, J.; Clarke, A. B.

    2010-12-01

    The scientific community has long since recognized the importance of sulfur dioxide (SO2) on climate change. The most universally accepted theory is that large amounts of SO2 injected into the atmosphere will react to form sulfate aerosols that reflect sunlight, thereby decreasing global temperature. This cooling effect has been observed after large eruptions throughout the geologic and historic records. The exact effect of SO2 on global climate though is still poorly understood. Estimates of global volcanic SO2 emissions rely primarily on two sets of data: ground-based measurements of SO2 fluxes using COSPEC or DOAS and more recently satellite observations. Both of these usually represent ‘snapshots’ of the gas emissions and at only a few places is continuous monitoring and data acquisition possible. Because continuous data are so rare, many assumptions have to be made when trying to estimate the global volcanic SO2 input to the atmosphere. This is especially true when it comes to frequently exploding volcanoes. Most of their background activity is very low in intensity or the gas plume may simply not reach the stratosphere, both of which make it impossible for satellite instruments to detect it. On the other hand, while individual explosions produce plumes big enough to be detected by satellite instruments, they are often not captured from the ground because no continuous monitoring is in place. Therefore neither satellite nor ground-based data fully represents the total SO2 emissions of these volcanoes. We have analyzed satellite data for several persistently active explosive volcanic centers in an attempt to determine whether their SO2 emissions are detectable and to what extent we can quantify them. We used data from the Ozone Monitoring Instrument (OMI), which operates in the UV spectrum, the Moderate Resolution Imaging Spectroradiometer (MODIS) and, when available, the Advanced Spaceborne Thermal Emission Radiometer (ASTER), both of which operate in the

  2. Identification of a small molecule with activity against drug-resistant and persistent tuberculosis

    PubMed Central

    Wang, Feng; Sambandan, Dhinakaran; Halder, Rajkumar; Wang, Jianing; Batt, Sarah M.; Weinrick, Brian; Ahmad, Insha; Yang, Pengyu; Zhang, Yong; Kim, John; Hassani, Morad; Huszar, Stanislav; Trefzer, Claudia; Ma, Zhenkun; Kaneko, Takushi; Mdluli, Khisi E.; Franzblau, Scott; Chatterjee, Arnab K.; Johnsson, Kai; Mikusova, Katarina; Besra, Gurdyal S.; Fütterer, Klaus; Robbins, Scott H.; Barnes, S. Whitney; Walker, John R.; Jacobs, William R.; Schultz, Peter G.

    2013-01-01

    A cell-based phenotypic screen for inhibitors of biofilm formation in mycobacteria identified the small molecule TCA1, which has bactericidal activity against both drug-susceptible and -resistant Mycobacterium tuberculosis (Mtb) and sterilizes Mtb in vitro combined with rifampicin or isoniazid. In addition, TCA1 has bactericidal activity against nonreplicating Mtb in vitro and is efficacious in acute and chronic Mtb infection mouse models both alone and combined with rifampicin or isoniazid. Transcriptional analysis revealed that TCA1 down-regulates genes known to be involved in Mtb persistence. Genetic and affinity-based methods identified decaprenyl-phosphoryl-β-D-ribofuranose oxidoreductase DprE1 and MoeW, enzymes involved in cell wall and molybdenum cofactor biosynthesis, respectively, as targets responsible for the activity of TCA1. These in vitro and in vivo results indicate that this compound functions by a unique mechanism and suggest that TCA1 may lead to the development of a class of antituberculosis agents. PMID:23776209

  3. Stable and unstable phases of elevated seismic activity at the persistently restless Telica Volcano, Nicaragua

    NASA Astrophysics Data System (ADS)

    Rodgers, Mel; Roman, Diana C.; Geirsson, Halldor; LaFemina, Peter; McNutt, Stephen R.; Muñoz, Angelica; Tenorio, Virginia

    2015-01-01

    Telica Volcano, Nicaragua, is a persistently restless volcano with daily seismicity rates that can vary by orders of magnitude without apparent connection to eruptive activity. Low-frequency (LF) events are dominant and peaks in seismicity rate show little correlation with eruptive episodes, presenting a challenge for seismic monitoring and eruption forecasting. A short period seismic station (TELN) has been operated on Telica's summit since 1993, and in 2010 the installation of a six-station broadband seismic and eleven-station continuous GPS network (the TESAND network) was completed to document in detail the seismic characteristics of a persistently restless volcano. Between our study period of November 2009 and May 2013, over 400,000 events were detected at the TESAND summit station (TBTN), with daily event rates ranging from 5 to 1400. We present spectral analyses and classifications of ~ 200,000 events recorded by the TESAND network between April 2010 and March 2013, and earthquake locations for a sub-set of events between July 2010 and February 2012. In 2011 Telica erupted in a series of phreatic vulcanian explosions. Six months before the 2011 eruption, we observe a sudden decrease in LF events concurrent with a swarm of high-frequency (HF) events, followed by a decline in overall event rates, which reached a minimum at the eruption onset. We observe repeated periods of high and low seismicity rates and suggest these changes in seismicity represent repeated transitions between open-system and closed-system degassing. We suggest that these short- and long-term transitions between open to closed-system degassing form part of a long-term pattern of stable vs. unstable phases at Telica. Stable phases are characterised by steady high-rate seismicity and represent stable open-system degassing, whereas unstable phases are characterised by highly variable seismicity rates and represent repeated transitions from open to closed-system degassing, where the system is

  4. Sunlight-activated long-persistent luminescence in the near-infrared from Cr(3+)-doped zinc gallogermanates.

    PubMed

    Pan, Zhengwei; Lu, Yi-Ying; Liu, Feng

    2012-01-01

    Visible-light persistent phosphors are being widely used as self-sustained night-vision materials because of their sufficiently strong and long afterglow (>10 h) and their ability to be excited by sunlight as well as room light. In contrast, persistent phosphors for near-infrared (NIR) wavelengths are lacking. Here we report a series of Cr(3+)-doped zinc gallogermanate NIR persistent phosphors that exhibit strong emission at 650-1,000 nm, extending beyond the typical 690-750 nm, and with a super-long afterglow of more than 360 h. These new NIR persistent phosphors are all-weather materials that can be rapidly, effectively and repeatedly charged by natural sunlight in almost all kinds of outdoor environment. Seconds to minutes of sunlight activation can result in more than two weeks of persistent NIR light emission. This new series of NIR persistent materials have potential applications in night-vision surveillance, solar energy utilization and in vivo bio-imaging. PMID:22101812

  5. Sunlight-activated long-persistent luminescence in the near-infrared from Cr3+-doped zinc gallogermanates

    NASA Astrophysics Data System (ADS)

    Pan, Zhengwei; Lu, Yi-Ying; Liu, Feng

    2012-01-01

    Visible-light persistent phosphors are being widely used as self-sustained night-vision materials because of their sufficiently strong and long afterglow (>10 h) and their ability to be excited by sunlight as well as room light. In contrast, persistent phosphors for near-infrared (NIR) wavelengths are lacking. Here we report a series of Cr3+-doped zinc gallogermanate NIR persistent phosphors that exhibit strong emission at 650-1,000 nm, extending beyond the typical 690-750 nm, and with a super-long afterglow of more than 360 h. These new NIR persistent phosphors are all-weather materials that can be rapidly, effectively and repeatedly charged by natural sunlight in almost all kinds of outdoor environment. Seconds to minutes of sunlight activation can result in more than two weeks of persistent NIR light emission. This new series of NIR persistent materials have potential applications in night-vision surveillance, solar energy utilization and in vivo bio-imaging.

  6. Persistent high paleosecular variation activity in southern hemisphere for at least 10 000 years

    NASA Astrophysics Data System (ADS)

    Constable, Catherine; Korte, Monika; Panovska, Sanja

    2016-11-01

    Direct observations of the geomagnetic field show that secular variation is strong in the Atlantic hemisphere, and comparatively reduced in the Pacific region. The dipole has been decaying since at least 1840 AD, driven by growth and migration of reverse flux patches in the southern hemisphere. We investigate whether anything like this modern pattern of geomagnetic secular variation persists and can be detected in global paleomagnetic field models. Synthesis of results from two new time-varying spherical harmonic models shows that geographically distinct geomagnetic secular variation extends to at least 10 000 BP. The models use the same database but differ in methodology, leading to some regional differences in results. Consistent large-scale surface features include strong average fields in the northern hemisphere and weaker fields with greater overall variability in the south. Longitudinal structure is present, with weaker average fields in the western Pacific than in the east, and prominent negative inclination anomalies extending beneath Indonesia, across Africa and to Brazil, but weaker anomalies in the central Pacific. Marginally positive inclination anomalies occur west of the Americas. Paleosecular variation activity peaks at high southern latitudes, and there is a pattern of reduced activity at equatorial and mid-latitudes beneath the Pacific. Although the dipole has exhibited both growth and decay over the interval 0-10 000 BP, our results show that geomagnetic paleosecular variation is preferentially focused in similar geographic regions to secular variation seen in the modern field.

  7. Insights into the emission reductions of multiple unintentional persistent organic pollutants from industrial activities.

    PubMed

    Liu, Guorui; Zheng, Minghui; Jiang, Xiaoxu; Jin, Rong; Zhao, Yuyang; Zhan, Jiayu

    2016-02-01

    Industrial activities result in unintentional production of multiple types of persistent organic pollutants (POPs) at various concentrations. Because of the potential adverse effect of these POPs on the environment, biota and human health, methods for controlling emission of POPs are required. Development and application of techniques for controlling emissions of POPs can be a technical and economic burden for the industry involved. Therefore, from the point of view of cost-benefit analysis, reducing emissions of multiple pollutants at the same time is optimal for sustainable industrial development. Although techniques have been developed for reducing the emissions of individual POPs, such as dioxins, further work is required on multi-POP control emissions from industrial activities. This paper discusses three important aspects that need to be taken to achieve multi-POP control. These aspects include the establishment of a comprehensive system for evaluating the risk from emissions of multiple POPs, determination of indicators for total emissions of multiple POPs, and the preparation and application of functional materials to inhibit formation of multiple POPs. These discussion might be helpful for the future research on the multi-POP control in industry.

  8. Effect of Exercise Training on Enos Expression, NO Production and Oxygen Metabolism in Human Placenta

    PubMed Central

    Ramírez-Vélez, Robinson; Bustamante, Juanita; Czerniczyniec, Analia; Aguilar de Plata, Ana C.; Lores-Arnaiz, Silvia

    2013-01-01

    Objective To determine the effects of combined aerobic and resistance exercise training during the second half of pregnancy on endothelial NOS expression (eNOS), nitric oxide (NO) production and oxygen metabolism in human placenta. Methods The study included 20 nulliparous in gestational week 16–20, attending prenatal care at three tertiary hospitals in Colombia who were randomly assigned into one of two groups: The exercise group (n = 10) took part in an exercise session three times a week for 12 weeks which consisted of: aerobic exercise at an intensity of 55–75% of their maximum heart rate for 60 min and 25 mins. Resistance exercise included 5 exercise groups circuit training (50 repetitions of each) using barbells (1–3 kg/exercise) and low-to-medium resistance bands. The control group (n = 10) undertook their usual physical activity. Mitochondrial and cytosol fractions were isolated from human placental tissue by differential centrifugation. A spectrophotometric assay was used to measure NO production in cytosolic samples from placental tissue and Western Blot technique to determine eNOS expression. Mitochondrial superoxide levels and hydrogen peroxide were measured to determine oxygen metabolism. Results Combined aerobic and resistance exercise training during pregnancy leads to a 2-fold increase in eNOS expression and 4-fold increase in NO production in placental cytosol (p = 0.05). Mitochondrial superoxide levels and hydrogen peroxide production rate were decreased by 8% and 37% respectively in the placental mitochondria of exercising women (p = 0.05). Conclusion Regular exercise training during the second half of pregnancy increases eNOS expression and NO production and decreases reactive oxygen species generation in human placenta. Collectively, these data demonstrate that chronic exercise increases eNOS/NO production, presumably by increasing endothelial shear stress. This adaptation may contribute to the beneficial effects of

  9. Bacterial persistence is an active σS stress response to metabolic flux limitation.

    PubMed

    Radzikowski, Jakub Leszek; Vedelaar, Silke; Siegel, David; Ortega, Álvaro Dario; Schmidt, Alexander; Heinemann, Matthias

    2016-09-21

    While persisters are a health threat due to their transient antibiotic tolerance, little is known about their phenotype and what actually causes persistence. Using a new method for persister generation and high-throughput methods, we comprehensively mapped the molecular phenotype of Escherichia coli during the entry and in the state of persistence in nutrient-rich conditions. The persister proteome is characterized by σ(S)-mediated stress response and a shift to catabolism, a proteome that starved cells tried to but could not reach due to absence of a carbon and energy source. Metabolism of persisters is geared toward energy production, with depleted metabolite pools. We developed and experimentally verified a model, in which persistence is established through a system-level feedback: Strong perturbations of metabolic homeostasis cause metabolic fluxes to collapse, prohibiting adjustments toward restoring homeostasis. This vicious cycle is stabilized and modulated by high ppGpp levels, toxin/anti-toxin systems, and the σ(S)-mediated stress response. Our system-level model consistently integrates past findings with our new data, thereby providing an important basis for future research on persisters.

  10. Bacterial persistence is an active σS stress response to metabolic flux limitation.

    PubMed

    Radzikowski, Jakub Leszek; Vedelaar, Silke; Siegel, David; Ortega, Álvaro Dario; Schmidt, Alexander; Heinemann, Matthias

    2016-01-01

    While persisters are a health threat due to their transient antibiotic tolerance, little is known about their phenotype and what actually causes persistence. Using a new method for persister generation and high-throughput methods, we comprehensively mapped the molecular phenotype of Escherichia coli during the entry and in the state of persistence in nutrient-rich conditions. The persister proteome is characterized by σ(S)-mediated stress response and a shift to catabolism, a proteome that starved cells tried to but could not reach due to absence of a carbon and energy source. Metabolism of persisters is geared toward energy production, with depleted metabolite pools. We developed and experimentally verified a model, in which persistence is established through a system-level feedback: Strong perturbations of metabolic homeostasis cause metabolic fluxes to collapse, prohibiting adjustments toward restoring homeostasis. This vicious cycle is stabilized and modulated by high ppGpp levels, toxin/anti-toxin systems, and the σ(S)-mediated stress response. Our system-level model consistently integrates past findings with our new data, thereby providing an important basis for future research on persisters. PMID:27655400

  11. Activity-dependent alternative splicing increases persistent sodium current and promotes seizure

    PubMed Central

    Lin, Wei-Hsiang; Günay, Cengiz; Marley, Richard; Prinz, Astrid A.; Baines, Richard A.

    2012-01-01

    Activity of voltage-gated Na channels (Nav) is modified by alternative splicing. However, whether altered splicing of human Nav’s contributes to epilepsy remains to be conclusively shown. We show here that altered splicing of the Drosophila Nav (paralytic, DmNav) contributes to seizure-like behaviour in identified seizure-mutants. We focus attention on a pair of mutually-exclusive alternate exons (termed K and L), which form part of the voltage sensor (S4) in domain III of the expressed channel. The presence of exon L results in a large, non-inactivating, persistent INap. Many forms of human epilepsy are associated with an increase in this current. In wildtype (WT) Drosophila larvae ~70-80% of DmNav transcripts contain exon L, the remainder contain exon K. Splicing of DmNav to include exon L is increased to ~100% in both the slamdance and easily-shocked seizure-mutants. This change to splicing is prevented by reducing synaptic activity levels through exposure to the antiepileptic phenytoin or the inhibitory transmitter GABA. Conversely, enhancing synaptic activity in WT, by feeding of picrotoxin, is sufficient to increase INap and promote seizure through increased inclusion of exon L to 100%. We also show that the underlying activity-dependent mechanism requires the presence of Pasilla, an RNA-binding protein. Finally, we use computational modelling to show that increasing INap is sufficient to potentiate membrane excitability consistent with a seizure phenotype. Thus, increased synaptic excitation favors inclusion of exon L which, in turn, further increases neuronal excitability. Thus, at least in Drosophila, this self-reinforcing cycle may promote the incidence of seizure. PMID:22623672

  12. Environmentally persistent free radicals inhibit cytochrome P450 activity in rat liver microsomes.

    PubMed

    Reed, James R; Cawley, George F; Ardoin, Taylor G; Dellinger, Barry; Lomnicki, Slawomir M; Hasan, Farhana; Kiruri, Lucy W; Backes, Wayne L

    2014-06-01

    Combustion processes generate particulate matter that affects human health. When incineration fuels include components that are highly enriched in aromatic hydrocarbons (especially halogenated varieties) and redox-active metals, ultrafine particulate matter containing air-stable, environmentally persistent free radicals (EPFRs) is generated. The exposure to fine EPFRs (less than 2.5 μm in diameter) has been shown to negatively influence pulmonary and cardiovascular functions in living organisms. The goal of this study was to determine if these EPFRs have a direct effect on cytochrome P450 function. This was accomplished by direct addition of the EPFRs to rat liver microsomal preparations and measurement of several P450 activities using form-selective substrates. The EPFRs used in this study were formed by heating vapors from an organic compound (either monochlorophenol (MCP230) or 1,2-dichlorobenzene (DCB230)) and 5% copper oxide supported on silica (approximately 0.2 μm in diameter) to 230°C under vacuum. Both types of EPFRs (but not silica, physisorbed silica, or silica impregnated with copper oxide) dramatically inhibited the activities of CYP1A, CYP2B, CYP2E1, CYP2D2 and CYP3A when incubated at concentrations less than 0.1 mg/ml with microsomes and NADPH. Interestingly, at the same concentrations, the EPFRs did not inhibit HO-1 activity or the reduction of cytochrome c by NADPH-cytochrome P450 reductase. CYP2D2-selective metabolism by rat liver microsomes was examined in more detail. The inhibition of CYP2D2-selective metabolism by both DCB230- and MCP230-EPFRs appeared to be largely noncompetitive and was attenuated in the presence of catalase suggesting that reactive oxygen species may be involved in the mechanism of inhibition.

  13. Circuits constructed from identified Aplysia neurons exhibit multiple patterns of persistent activity.

    PubMed Central

    Kleinfeld, D; Raccuia-Behling, F; Chiel, H J

    1990-01-01

    We have used identified neurons from the abdominal ganglion of the mollusc Aplysia to construct and analyze two circuits in vitro. Each of these circuits was capable of producing two patterns of persistent activity; that is, they had bistable output states. The output could be switched between the stable states by a brief, external input. One circuit consisted of cocultured L10 and left upper quadrant (LUQ) neurons that formed reciprocal, inhibitory connections. In one stable state L10 was active and the LUQ was quiescent, whereas in the other stable state L10 was quiescent and the LUQ was active. A second circuit consisted of co-cultured L7 and L12 neurons that formed reciprocal, excitatory connections. In this circuit, both cells were quiescent in one stable state and both cells fired continuously in the other state. Bistable output in both circuits resulted from the nonlinear firing characteristics of each neuron and the feedback between the two neurons. We explored how the stability of the neuronal output could be controlled by the background currents injected into each neuron. We observed a relatively well-defined range of currents for which bistability occurred, consistent with the values expected from the measured strengths of the connections and a simple model. Outside of the range, the output was stable in only a single state. These results suggest how stable patterns of output are produced by some in vivo circuits and how command neurons from higher neural centers may control the activity of these circuits. The criteria that guided us in forming our circuits in culture were derived from theoretical studies on the properties of certain neuronal network models (e.g., Hopfield, J. J. 1984. Proc. Natl. Acad. Sci. USA. 81:3088-3092). Our results show that circuits consisting of only two co-cultured neurons can exhibit bistable output states of the form hypothesized to occur in populations of neurons. Images FIGURE 3 PMID:2344460

  14. Persistent aeolian activity at Endeavour crater, Meridiani Planum, Mars; new observations from orbit and the surface

    NASA Astrophysics Data System (ADS)

    Chojnacki, Matthew; Johnson, Jeffrey R.; Moersch, Jeffrey E.; Fenton, Lori K.; Michaels, Timothy I.; Bell, James F., III

    2015-05-01

    Aeolian-driven bedform activity is now known to occur in many regions of Mars, based on surface and orbital observation of contemporary martian ripple and dune mobility events. Many of these sites have only been monitored with sufficient resolution data for the last few Mars years, when the High Resolution Imaging Science Experiment (HiRISE) began acquiring images of Mars. One exception is the well-monitored Endeavour crater in Meridiani Planum, which was one of the first known sites of unambiguous dune activity (migration and deflation). However, those early detections used lower resolution images over longer temporal baselines (versus the HIRISE data now available), leaving some measurements poorly constrained. New orbital and surface observations of Endeavour show multiple spatial (cm, m, km) and temporal (seasons, Mars year) scales of aeolian-driven surface change, which confirms earlier reports. Dome dunes in the eastern portion of the crater persistently deflate, disseminating dark sand across lighter-toned regolith and/or eroded bright dust, and likely contribute to the crater interior's episodic decreases in orbital albedo measurements. Other dome dunes are detected with the highest migration rates (4-12 m per Mars year) and volumetric sand fluxes reported yet for Mars. Estimated dune construction times or "turnover times" here and elsewhere on Mars are significantly shorter than martian obliquity cycles, implying that it is not necessary to invoke paleoclimate wind regimes to explain current dune morphologies. Located on the crater rim, the Opportunity rover detected evidence for near- and far-field aeolian-driven activity, with observations of spherules/sand movement in the rover workspace, bedform albedo alteration, and dust-lifting events. Observations of intracrater dunes show periodic shifting dark streaks that significantly constrain local wind regimes (directionality and seasonality). Constraints on wind directions from surface and orbital images

  15. Enhanced photocatalytic activity and persistent luminescence in Zn2GeO4:Mn2+ by Eu3+ doping

    NASA Astrophysics Data System (ADS)

    Li, Hong; Wang, Yinhai; Li, Lei; Huang, Haiju; Zhao, Hui; Hu, Zhengfa

    2016-09-01

    Zn2GeO4:Mn2+,Eu3+ and Zn2GeO4:Mn2+ powders were synthesized by a high-temperature solid-state reaction. X-ray powder diffraction (XRD) and scanning electron microscopy (SEM) were used to characterize the structures and morphologies of the synthesized powders, respectively. The photocatalytic properties and long persistent luminescence performance were improved by Eu3+ doping. Thermoluminescent (TL) curves showed that the trap concentration in the material was increased with Eu3+ doping, which formed trap centers in Zn2GeO4:Mn2+. The trap centers can capture the electrons or holes and subsequently increase the separation of photogenerated electrons and holes by suppressing the recombination of captured electrons and holes; thus, resulting in an improved photocatalytic activity and a prolonged persistent luminescence. The present strategy may be used as a general method to improve the photocatalytic activity and persistent luminescence.

  16. T-13910 DNA variant associated with lactase persistence interacts with Oct-1 and stimulates lactase promoter activity in vitro.

    PubMed

    Lewinsky, Rikke H; Jensen, Tine G K; Møller, Jette; Stensballe, Allan; Olsen, Jørgen; Troelsen, Jesper T

    2005-12-15

    Two phenotypes exist in the human population with regard to expression of lactase in adults. Lactase non-persistence (adult-type hypolactasia and lactose intolerance) is characterized by a decline in the expression of lactase-phlorizin hydrolase (LPH) after weaning. In contrast, lactase-persistent individuals have a high LPH throughout their lifespan. Lactase persistence and non-persistence are associated with a T/C polymorphism at position -13,910 upstream the lactase gene. A nuclear factor binds more strongly to the T-13,910 variant associated with lactase persistence than the C-13,910 variant associated with lactase non-persistence. Oct-1 and glyceraldehyde-3-phosphate dehydrogenase were co-purified by DNA affinity purification using the sequence of the T-13,910 variant. Supershift analyses show that Oct-1 binds directly to the T-13,910 variant, and we suggest that GAPDH is co-purified due to interactions with Oct-1. Expression of Oct-1 stimulates reporter gene expression from the T and the C-13,910 variant/LPH promoter constructs only when it is co-expressed with HNF1alpha. Binding sites for other intestinal transcription factors (GATA-6, HNF4alpha, Fox and Cdx-2) were identified in the region of the -13,910 T/C polymorphism. Three of these sites are required for the enhancer activity of the -13,910 region. The data suggest that the binding of Oct-1 to the T-13,910 variant directs increased lactase promoter activity and this might provide an explanation for the lactase persistence phenotype in the human population.

  17. Two functionally distinct pools of eNOS in endothelium are facilitated by myoendothelial junction lipid composition.

    PubMed

    Biwer, Lauren A; Taddeo, Evan P; Kenwood, Brandon M; Hoehn, Kyle L; Straub, Adam C; Isakson, Brant E

    2016-07-01

    In resistance arteries, endothelial cells (EC) make contact with smooth muscle cells (SMC), forming myoendothelial junctions (MEJ). Endothelial nitric oxide synthase (eNOS) is present in the luminal side of the EC (apical EC) and the basal side of the EC (MEJ). To test if these eNOS pools acted in sync or separately, we co-cultured ECs and SMCs, then stimulated SMCs with phenylephrine (PE). Adrenergic activation causes inositol [1,4,5] triphosphate (IP3) to move from SMC to EC through gap junctions at the MEJ. PE increases MEJ eNOS phosphorylation (eNOS-P) at S1177, but not in EC. Conversely, we used bradykinin (BK) to increase EC calcium; this increased EC eNOS-P but did not affect MEJ eNOS-P. Inhibiting gap junctions abrogated the MEJ eNOS-P after PE, but had no effect on BK eNOS-P. Differential lipid composition between apical EC and MEJ may account for the compartmentalized eNOS-P response. Indeed, DAG and phosphatidylserine are both enriched in MEJ. These lipids are cofactors for PKC activity, which was significantly increased at the MEJ after PE. Because PKC activity also relies on endoplasmic reticulum (ER) calcium release, we used thapsigargin and xestospongin C, BAPTA, and PKC inhibitors, which caused significant decreases in MEJ eNOS-P after PE. Functionally, BK inhibited leukocyte adhesion and PE caused an increase in SMC cGMP. We hypothesize that local lipid composition of the MEJ primes PKC and eNOS-P for stimulation by PE, allowing for compartmentalized function of eNOS in the blood vessel wall. PMID:27106139

  18. The persistence of the NWA effect during the low solar activity period 2007-2009

    NASA Astrophysics Data System (ADS)

    Jakowski, N.; Hoque, M. M.; Kriegel, M.; Patidar, V.

    2015-10-01

    The ionospheric Nighttime Winter Anomaly (NWA) was first reported more than three decades ago based on total electron content (TEC) and vertical sounding data. The aim of this paper is to provide further evidence that the NWA effect is a persistent feature in the Northern Hemisphere at the American and in the Southern Hemisphere at the Asian longitude sector under low solar activity conditions. The analysis of ground-based GPS derived TEC and peak electron density data from radio occultation measurements on Formosat-3/COSMIC satellites confirms and further supports the findings published in earlier NWA papers. So it has been confirmed and further specified that the NWA appears at longitude sectors where the displacement between the geomagnetic and the geographic equator maximizes. Here NWA peaks at around 40°-50° geomagnetic midlatitude supporting the idea that wind-induced plasma uplifting in the conjugated summer hemisphere is the main driving force for the accumulation of ionospheric plasma in the topside ionosphere and plasmasphere. In parallel, the midsummer nighttime anomaly (MSNA) is caused at the local ionosphere. Simultaneously, interhemispheric coupling causes severe downward plasma fluxes in the conjugated winter hemisphere during night causing the NWA at low solar activity. With increasing solar activity, the downward plasma fluxes lose their impact due to the much stronger increasing background ionization that masks the NWA. It is assumed that MSNA and related special anomalies such as the Weddell Sea Anomaly and the Okhotsk Sea Anomaly are closely related to the NWA via enhanced wind-induced uplifting of the ionosphere.

  19. New paradigms for understanding and step changes in treating active and chronic, persistent apicomplexan infections

    PubMed Central

    McPhillie, Martin; Zhou, Ying; El Bissati, Kamal; Dubey, Jitender; Lorenzi, Hernan; Capper, Michael; Lukens, Amanda K; Hickman, Mark; Muench, Stephen; Verma, Shiv Kumar; Weber, Christopher R.; Wheeler, Kelsey; Gordon, James; Sanders, Justin; Moulton, Hong; Wang, Kai; Kim, Taek-Kyun; He, Yuqing; Santos, Tatiana; Woods, Stuart; Lee, Patty; Donkin, David; Kim, Eric; Fraczek, Laura; Lykins, Joseph; Esaa, Farida; Alibana-Clouser, Fatima; Dovgin, Sarah; Weiss, Louis; Brasseur, Gael; Wirth, Dyann; Kent, Michael; Hood, Leroy; Meunieur, Brigitte; Roberts, Craig W.; Hasnain, S. Samar; Antonyuk, Svetlana V.; Fishwick, Colin; McLeod, Rima

    2016-01-01

    Toxoplasma gondii, the most common parasitic infection of human brain and eye, persists across lifetimes, can progressively damage sight, and is currently incurable. New, curative medicines are needed urgently. Herein, we develop novel models to facilitate drug development: EGS strain T. gondii forms cysts in vitro that induce oocysts in cats, the gold standard criterion for cysts. These cysts highly express cytochrome b. Using these models, we envisioned, and then created, novel 4-(1H)-quinolone scaffolds that target the cytochrome bc1 complex Qi site, of which, a substituted 5,6,7,8-tetrahydroquinolin-4-one inhibits active infection (IC50, 30 nM) and cysts (IC50, 4 μM) in vitro, and in vivo (25 mg/kg), and drug resistant Plasmodium falciparum (IC50, <30 nM), with clinically relevant synergy. Mutant yeast and co-crystallographic studies demonstrate binding to the bc1 complex Qi site. Our results have direct impact on improving outcomes for those with toxoplasmosis, malaria, and ~2 billion persons chronically infected with encysted bradyzoites. PMID:27412848

  20. New paradigms for understanding and step changes in treating active and chronic, persistent apicomplexan infections.

    PubMed

    McPhillie, Martin; Zhou, Ying; El Bissati, Kamal; Dubey, Jitender; Lorenzi, Hernan; Capper, Michael; Lukens, Amanda K; Hickman, Mark; Muench, Stephen; Verma, Shiv Kumar; Weber, Christopher R; Wheeler, Kelsey; Gordon, James; Sanders, Justin; Moulton, Hong; Wang, Kai; Kim, Taek-Kyun; He, Yuqing; Santos, Tatiana; Woods, Stuart; Lee, Patty; Donkin, David; Kim, Eric; Fraczek, Laura; Lykins, Joseph; Esaa, Farida; Alibana-Clouser, Fatima; Dovgin, Sarah; Weiss, Louis; Brasseur, Gael; Wirth, Dyann; Kent, Michael; Hood, Leroy; Meunieur, Brigitte; Roberts, Craig W; Hasnain, S Samar; Antonyuk, Svetlana V; Fishwick, Colin; McLeod, Rima

    2016-01-01

    Toxoplasma gondii, the most common parasitic infection of human brain and eye, persists across lifetimes, can progressively damage sight, and is currently incurable. New, curative medicines are needed urgently. Herein, we develop novel models to facilitate drug development: EGS strain T. gondii forms cysts in vitro that induce oocysts in cats, the gold standard criterion for cysts. These cysts highly express cytochrome b. Using these models, we envisioned, and then created, novel 4-(1H)-quinolone scaffolds that target the cytochrome bc1 complex Qi site, of which, a substituted 5,6,7,8-tetrahydroquinolin-4-one inhibits active infection (IC50, 30 nM) and cysts (IC50, 4 μM) in vitro, and in vivo (25 mg/kg), and drug resistant Plasmodium falciparum (IC50, <30 nM), with clinically relevant synergy. Mutant yeast and co-crystallographic studies demonstrate binding to the bc1 complex Qi site. Our results have direct impact on improving outcomes for those with toxoplasmosis, malaria, and ~2 billion persons chronically infected with encysted bradyzoites.

  1. New paradigms for understanding and step changes in treating active and chronic, persistent apicomplexan infections.

    PubMed

    McPhillie, Martin; Zhou, Ying; El Bissati, Kamal; Dubey, Jitender; Lorenzi, Hernan; Capper, Michael; Lukens, Amanda K; Hickman, Mark; Muench, Stephen; Verma, Shiv Kumar; Weber, Christopher R; Wheeler, Kelsey; Gordon, James; Sanders, Justin; Moulton, Hong; Wang, Kai; Kim, Taek-Kyun; He, Yuqing; Santos, Tatiana; Woods, Stuart; Lee, Patty; Donkin, David; Kim, Eric; Fraczek, Laura; Lykins, Joseph; Esaa, Farida; Alibana-Clouser, Fatima; Dovgin, Sarah; Weiss, Louis; Brasseur, Gael; Wirth, Dyann; Kent, Michael; Hood, Leroy; Meunieur, Brigitte; Roberts, Craig W; Hasnain, S Samar; Antonyuk, Svetlana V; Fishwick, Colin; McLeod, Rima

    2016-01-01

    Toxoplasma gondii, the most common parasitic infection of human brain and eye, persists across lifetimes, can progressively damage sight, and is currently incurable. New, curative medicines are needed urgently. Herein, we develop novel models to facilitate drug development: EGS strain T. gondii forms cysts in vitro that induce oocysts in cats, the gold standard criterion for cysts. These cysts highly express cytochrome b. Using these models, we envisioned, and then created, novel 4-(1H)-quinolone scaffolds that target the cytochrome bc1 complex Qi site, of which, a substituted 5,6,7,8-tetrahydroquinolin-4-one inhibits active infection (IC50, 30 nM) and cysts (IC50, 4 μM) in vitro, and in vivo (25 mg/kg), and drug resistant Plasmodium falciparum (IC50, <30 nM), with clinically relevant synergy. Mutant yeast and co-crystallographic studies demonstrate binding to the bc1 complex Qi site. Our results have direct impact on improving outcomes for those with toxoplasmosis, malaria, and ~2 billion persons chronically infected with encysted bradyzoites. PMID:27412848

  2. Persistent activation of STAT3 by PIM2-driven positive feedback loop for epithelial-mesenchymal transition in breast cancer.

    PubMed

    Uddin, Nizam; Kim, Rae-Kwon; Yoo, Ki-Chun; Kim, Young-Heon; Cui, Yan-Hong; Kim, In-Gyu; Suh, Yongjoon; Lee, Su-Jae

    2015-06-01

    Metastasis of breast cancer is promoted by epithelial-mesenchymal transition (EMT). Emerging evidence suggests that STAT3 is a critical signaling node in EMT and is constitutively activated in many carcinomas, including breast cancer. However, its signaling mechanisms underlying persistent activation of STAT3 associated with EMT remain obscure. Here, we report that PIM2 promotes activation of STAT3 through induction of cytokines. Activation of STAT3 caused an increase in PIM2 expression, implicating a positive feedback loop between PIM2 and STAT3. In agreement, targeting of either PIM2, STAT3 or PIM2-dependent cytokines suppressed EMT-associated migratory and invasive properties through inhibition of ZEB1. Taken together, our findings identify the signaling mechanisms underlying the persistent activation of STAT3 and the oncogenic role of PIM2 in EMT in breast cancer.

  3. Persistent activation of STAT3 by PIM2-driven positive feedback loop for epithelial-mesenchymal transition in breast cancer.

    PubMed

    Uddin, Nizam; Kim, Rae-Kwon; Yoo, Ki-Chun; Kim, Young-Heon; Cui, Yan-Hong; Kim, In-Gyu; Suh, Yongjoon; Lee, Su-Jae

    2015-06-01

    Metastasis of breast cancer is promoted by epithelial-mesenchymal transition (EMT). Emerging evidence suggests that STAT3 is a critical signaling node in EMT and is constitutively activated in many carcinomas, including breast cancer. However, its signaling mechanisms underlying persistent activation of STAT3 associated with EMT remain obscure. Here, we report that PIM2 promotes activation of STAT3 through induction of cytokines. Activation of STAT3 caused an increase in PIM2 expression, implicating a positive feedback loop between PIM2 and STAT3. In agreement, targeting of either PIM2, STAT3 or PIM2-dependent cytokines suppressed EMT-associated migratory and invasive properties through inhibition of ZEB1. Taken together, our findings identify the signaling mechanisms underlying the persistent activation of STAT3 and the oncogenic role of PIM2 in EMT in breast cancer. PMID:25854938

  4. Semibiotic Persistence

    NASA Astrophysics Data System (ADS)

    Prothmann, C.; Zauner, K.-P.

    From observation, we find four different strategies to successfully enable structures to persist over extended periods of time. If functionally relevant features are very large compared to the changes that can be effectuated by entropy, the functional structure itself has a high enough probability to erode only slowly over time. If the functionally relevant features are protected from environmental influence by sacrificial layers that absorb the impinging of the environment, deterioration can be avoided or slowed. Loss of functionality can be delayed, even for complex systems, by keeping alternate options for all required components available. Biological systems also apply information processing to actively counter the impact of entropy by mechanisms such as self-repair. The latter strategy increases the overall persistence of living systems and enables them to maintain a highly complex functional organisation during their lifetime and over generations. In contrast to the other strategies, information processing has only low material overhead. While at present engineered technology is far from achieving the self-repair of evolved systems, the semibiotic combination of biological components with conventionally engineered systems may open a path to long-term persistence of functional devices in harsh environments. We review nature's strategies for persistence, and consider early steps taken in the laboratory to import such capabilities into engineered architectures.

  5. Remarkable Functional Convergence: Alarmone ppGpp Mediates Persistence by Activating Type I and II Toxin-Antitoxins.

    PubMed

    Gerdes, Kenn; Maisonneuve, Etienne

    2015-07-01

    In this issue of Molecular Cell, Verstraeten et al. (2015) demonstrate that the conserved GTPase Obg and the second messenger ppGpp mediate persistence by activation of a type I toxin-antitoxin module (hokB/sokB) in E. coli.

  6. Hypercholesterolemia-induced erectile dysfunction: endothelial nitric oxide synthase (eNOS) uncoupling in the mouse penis by NAD(P)H oxidase

    PubMed Central

    Musicki, Biljana; Liu, Tongyun; Lagoda, Gwen A.; Strong, Travis D.; Sezen, Sena F.; Johnson, Justin M.; Burnett, Arthur L.

    2010-01-01

    INTRODUCTION Hypercholesterolemia induces erectile dysfunction (ED) mostly by increasing oxidative stress and impairing endothelial function in the penis, but the mechanisms regulating reactive oxygen species (ROS) production in the penis are not understood. AIMS We evaluated whether hypercholesterolemia activates nicotinamide adenine dinucleotide phosphate (NAD[P]H) oxidase in the penis, providing an initial source of ROS to induce endothelial nitric oxide synthase (eNOS) uncoupling and endothelial dysfunction resulting in ED. METHODS Low-density-lipoprotein receptor (LDLR)–null mice were fed Western diet for 4 weeks to induce early-stage hyperlipidemia. Wild type (WT) mice fed regular chow served as controls. Mice received NAD(P)H oxidase inhibitor apocynin (10 mM in drinking water) or vehicle. Erectile function was assessed in response to cavernous nerve electrical stimulation. Markers of endothelial function (phospho [P]-vasodilator-stimulated-protein [VASP]-Ser-239), oxidative stress (4-hydroxy-2-nonenal [HNE]), sources of ROS (eNOS uncoupling and NAD[P]H oxidase subunits p67phox, p47phox, and gp91phox), P-eNOS-Ser-1177, and eNOS were measured by Western blot in penes. MAIN OUTCOME MEASURES Molecular mechanisms of ROS generation and endothelial dysfunction in hypercholesterolemia-induced ED. RESULTS Erectile response was significantly (P<0.05) reduced in hypercholesterolemic LDLR-null mice compared to WT mice. Relative to WT mice, hypercholesterolemia increased (P<0.05) protein expressions of NAD(P)H oxidase subunits p67phox, p47phox and gp91phox, eNOS uncoupling, and 4-HNE-modified proteins, and reduced (P<0.05) P-VASP-Ser-239 expression in the penis. Apocynin treatment of LDLR-null mice preserved (P<0.05) maximal intracavernosal pressure, and reversed (P < 0.05) the abnormalities in protein expressions of gp67phox and gp47phox, 4-HNE, P-VASP-Ser-239, and eNOS uncoupling in the penis. Apocynin treatment of WT mice did not affect any of these parameters

  7. Altered Spontaneous Activity in Patients with Persistent Somatoform Pain Disorder Revealed by Regional Homogeneity.

    PubMed

    Huang, Tianming; Zhao, Zhiyong; Yan, Chao; Lu, Jing; Li, Xuzhou; Tang, Chaozheng; Fan, Mingxia; Luo, Yanli

    2016-01-01

    Persistent somatoform pain disorder (PSPD) is a mental disorder un-associated with any somatic injury and can cause severe somatosensory and emotional impairments in patients. However, so far, the neuro-pathophysiological mechanism of the functional impairments in PSPD is still unclear. The present study assesses the difference in regional spontaneous activity between PSPD and healthy controls (HC) during a resting state, in order to elucidate the neural mechanisms underlying PSPD. Resting-state functional Magnetic Resonance Imaging data were obtained from 13 PSPD patients and 23 age- and gender-matched HC subjects in this study. Kendall's coefficient of concordance was used to measure regional homogeneity (ReHo), and a two-sample t-test was subsequently performed to investigate the ReHo difference between PSPD and HC. Additionally, the correlations between the mean ReHo of each survived area and the clinical assessments were further analyzed. Compared with the HC group, patients with PSPD exhibited decreased ReHo in the bilateral primary somatosensory cortex, posterior cerebellum, and occipital lobe, while increased ReHo in the prefrontal cortex (PFC) and default mode network (including the medial PFC, right inferior parietal lobe (IPL), and left supramarginal gyrus). In addition, significant positive correlations were found between the mean ReHo of both right IPL and left supramarginal gyrus and participants' Self-Rating Anxiety Scale (SAS) scores, and between the mean ReHo of the left middle frontal gyrus and Visual Analogue Scale (VAS) scores. Our results suggest that abnormal spontaneous brain activity in specific brain regions during a resting state may be associated with the dysfunctions in pain, memory and emotional processing commonly observed in patients with PSPD. These findings help us to understand the neural mechanisms underlying PSPD and suggest that the ReHo metric could be used as a clinical marker for PSPD. PMID:26977802

  8. Altered Spontaneous Activity in Patients with Persistent Somatoform Pain Disorder Revealed by Regional Homogeneity

    PubMed Central

    Yan, Chao; Lu, Jing; Li, Xuzhou; Tang, Chaozheng; Fan, Mingxia; Luo, Yanli

    2016-01-01

    Persistent somatoform pain disorder (PSPD) is a mental disorder un-associated with any somatic injury and can cause severe somatosensory and emotional impairments in patients. However, so far, the neuro-pathophysiological mechanism of the functional impairments in PSPD is still unclear. The present study assesses the difference in regional spontaneous activity between PSPD and healthy controls (HC) during a resting state, in order to elucidate the neural mechanisms underlying PSPD. Resting-state functional Magnetic Resonance Imaging data were obtained from 13 PSPD patients and 23 age- and gender-matched HC subjects in this study. Kendall’s coefficient of concordance was used to measure regional homogeneity (ReHo), and a two-sample t-test was subsequently performed to investigate the ReHo difference between PSPD and HC. Additionally, the correlations between the mean ReHo of each survived area and the clinical assessments were further analyzed. Compared with the HC group, patients with PSPD exhibited decreased ReHo in the bilateral primary somatosensory cortex, posterior cerebellum, and occipital lobe, while increased ReHo in the prefrontal cortex (PFC) and default mode network (including the medial PFC, right inferior parietal lobe (IPL), and left supramarginal gyrus). In addition, significant positive correlations were found between the mean ReHo of both right IPL and left supramarginal gyrus and participants’ Self-Rating Anxiety Scale (SAS) scores, and between the mean ReHo of the left middle frontal gyrus and Visual Analogue Scale (VAS) scores. Our results suggest that abnormal spontaneous brain activity in specific brain regions during a resting state may be associated with the dysfunctions in pain, memory and emotional processing commonly observed in patients with PSPD. These findings help us to understand the neural mechanisms underlying PSPD and suggest that the ReHo metric could be used as a clinical marker for PSPD. PMID:26977802

  9. Reconsolidation-induced memory persistence: Participation of late phase hippocampal ERK activation.

    PubMed

    Krawczyk, M C; Navarro, N; Blake, M G; Romano, A; Feld, M; Boccia, M M

    2016-09-01

    Persistence is an attribute of long-term memories (LTM) that has recently caught researcher's attention in search for mechanisms triggered by experience that assure memory perdurability. Up-to-date, scarce evidence of relationship between reconsolidation and persistence has been described. Here, we characterized hippocampal ERK participation in LTM reconsolidation and persistence using an inhibitory avoidance task (IA) at different time points. Intra-dorsal-hippocampal (dHIP) administration of an ERK inhibitor (PD098059, PD, 1.0μg/hippocampus) 3h after retrieval did not affect reconsolidation of a strong IA, when tested 24h apart. However, the same manipulation impaired performance when animals were tested at 7d, regardless of the training's strength; and being specific to memory reactivation. To the best of our knowledge, this is the first report showing that persistence might be triggered after memory reactivation involving an ERK/MAPK-dependent process.

  10. Reconsolidation-induced memory persistence: Participation of late phase hippocampal ERK activation.

    PubMed

    Krawczyk, M C; Navarro, N; Blake, M G; Romano, A; Feld, M; Boccia, M M

    2016-09-01

    Persistence is an attribute of long-term memories (LTM) that has recently caught researcher's attention in search for mechanisms triggered by experience that assure memory perdurability. Up-to-date, scarce evidence of relationship between reconsolidation and persistence has been described. Here, we characterized hippocampal ERK participation in LTM reconsolidation and persistence using an inhibitory avoidance task (IA) at different time points. Intra-dorsal-hippocampal (dHIP) administration of an ERK inhibitor (PD098059, PD, 1.0μg/hippocampus) 3h after retrieval did not affect reconsolidation of a strong IA, when tested 24h apart. However, the same manipulation impaired performance when animals were tested at 7d, regardless of the training's strength; and being specific to memory reactivation. To the best of our knowledge, this is the first report showing that persistence might be triggered after memory reactivation involving an ERK/MAPK-dependent process. PMID:27321160

  11. Living Water. Eno River State Park: An Environmental Education Learning Experience Designed for the Middle Grades.

    ERIC Educational Resources Information Center

    Hartley, Scott; Woods, Martha

    This learning packet, one in a series of eight, was developed by the Eno River State Park in North Carolina for Grades 5-6 to teach about various aspects of water life on the Eno River. Loose-leaf pages are presented in nine sections that contain: (1) introductions to the North Carolina State Park System, the Eno River State Park, and to the…

  12. Environmentally persistent free radicals inhibit cytochrome P450 activity in rat liver microsomes

    SciTech Connect

    Reed, James R.; Cawley, George F.; Ardoin, Taylor G.; Dellinger, Barry; Lomnicki, Slawomir M.; Hasan, Farhana; Kiruri, Lucy W.; Backes, Wayne L.

    2014-06-01

    Combustion processes generate particulate matter that affects human health. When incineration fuels include components that are highly enriched in aromatic hydrocarbons (especially halogenated varieties) and redox-active metals, ultrafine particulate matter containing air-stable, environmentally persistent free radicals (EPFRs) is generated. The exposure to fine EPFRs (less than 2.5 μm in diameter) has been shown to negatively influence pulmonary and cardiovascular functions in living organisms. The goal of this study was to determine if these EPFRs have a direct effect on cytochrome P450 function. This was accomplished by direct addition of the EPFRs to rat liver microsomal preparations and measurement of several P450 activities using form-selective substrates. The EPFRs used in this study were formed by heating vapors from an organic compound (either monochlorophenol (MCP230) or 1,2-dichlorobenzene (DCB230)) and 5% copper oxide supported on silica (approximately 0.2 μm in diameter) to 230 °C under vacuum. Both types of EPFRs (but not silica, physisorbed silica, or silica impregnated with copper oxide) dramatically inhibited the activities of CYP1A, CYP2B, CYP2E1, CYP2D2 and CYP3A when incubated at concentrations less than 0.1 mg/ml with microsomes and NADPH. Interestingly, at the same concentrations, the EPFRs did not inhibit HO-1 activity or the reduction of cytochrome c by NADPH-cytochrome P450 reductase. CYP2D2-selective metabolism by rat liver microsomes was examined in more detail. The inhibition of CYP2D2-selective metabolism by both DCB230- and MCP230-EPFRs appeared to be largely noncompetitive and was attenuated in the presence of catalase suggesting that reactive oxygen species may be involved in the mechanism of inhibition. - Highlights: • Combustion of organic pollutants generates long-lived particulate radicals (EPFRs). • EPFRs inhibit metabolism by all cytochromes P450 tested in rat liver microsomes. • EPFR-mediated inhibition is related to

  13. Resveratrol Prevented Lipopolysaccharide-Induced Endothelial Dysfunction in Rat Thoracic Aorta Through Increased eNOS Expression

    PubMed Central

    Uğurel, Seda Sultan; Kuşçu, Nilay; Özenci, Çiler Çelik; Dalaklıoğlu, Selvinaz; Taşatargil, Arda

    2016-01-01

    Background: The cardiovascular benefits of Resveratrol (RVT) have been well established by previous experimental and clinical studies. Aims: The goal of this study was to test the effectiveness of RVT administration on the impaired endothelial function induced by lipopolysaccharide (LPS), and to elucidate the role of endothelial nitric oxide synthase (eNOS)/Sirtuin 1 (SIRT1) pathway. Study Design: Animal experiment. Methods: Endotoxemia was induced by intraperitoneal injection of 10 mg/kg LPS, and the thoracic aorta was isolated six hours later. RVT was injected intraperitoneally 15 minutes before LPS administration. Six hours after LPS injection, potassium chloride (KCl), phenylephrine (Phe), acetylcholine (ACh), and sodium nitroprusside (SNP) were used to examine to vascular reactivity and endothelial function. eNOS, phospho-eNOS (p-eNOS) (Ser 1177), and SIRT1 expressions in thoracic aorta were evaluated by Western blot. Results: LPS administration significantly inhibited the relaxation response induced by ACh, while the relaxation to SNP was not significantly altered. Phe- and KCl-induced contractile responses in the thoracic aorta significantly decreased in LPS-injected group. eNOS and p-eNOS expression decreased significantly in arteries obtained from LPS group rats. The impaired vasoreactivity as well as decreased expressions of eNOS, p-eNOS, and SIRT1 in vessels from LPS-injected rats were improved by RVT treatment. Conclusion: The endothelium-dependent vasodilatation of the thoracic aorta was significantly inhibited by LPS administration, and RVT treatment may improve vascular endothelial function. The protective effect of RVT might be associated with increased eNOS expression and activity. PMID:27403381

  14. Multi-temporal behaviour of a persistently active volcano - Masaya, Nicaragua

    NASA Astrophysics Data System (ADS)

    Williams-Jones, G.; Mauri, G.

    2007-05-01

    An in depth understanding of the processes responsible for persistent volcanism can only be achieved through the integration of multi-temporal geophysical and geochemical techniques. Gravity changes combined with ground deformation and gas flux have provided important information on magma reservoir mass changes and rates of magma emplacement or recharge. While the long-term micro-gravity, ground deformation and SO2 flux data collected at Masaya volcano (Nicaragua) since 1993 has identified significant multi-year cycles of activity, recent continuous micro-gravity surveys have shown significant short-term signals. Current activity is characterised by repeated periods of significant passive degassing (>2000 t/d SO2) with infrequent vent-clearing eruptions of negligible amounts of juvenile material. The multi-year gravity and gas flux variations are most likely due to gas accumulation in the shallow substructure controlled by the convective overturn of shallow degassed, cooled and dense magma replaced periodically by lower density, hot, gas-rich magma from depth. However, the presence of a small hydrothermal system can act as a physical and chemical buffer to the volcanic system while the essentially 'open' nature of Masaya's substructure can obscure short-term variations. In order to investigate the origin and importance of these short-term variations, continuous gravity and deformation surveys were made in March 2006 and 2007 in the summit craters of Masaya. During this period, residual gravity variations of ~60 µGal were measured with wavelengths of ~20 hours. These variations may be due in part to rapid changes in the hydrothermal system, occilations in height of the magma column or changes in vesiculation due to varying rates of gas flux. Concurrent detailed self-potential (SP) mapping, with soil CO2 and temperature measurements, delineated the shape and position of a small hydrothermal system centered on the main Nindiri crater. Processing of the SP data by

  15. Medial prefrontal cortical activity reflects dynamic re-evaluation during voluntary persistence

    PubMed Central

    McGuire, Joseph T.; Kable, Joseph W.

    2015-01-01

    Deciding how long to keep waiting for future rewards is a nontrivial problem, especially when the timing of rewards is uncertain. We report an experiment in which human decision makers waited for rewards in two environments, in which reward-timing statistics favored either a greater or lesser degree of behavioral persistence. We found that decision makers adaptively calibrated their level of persistence for each environment. Functional neuroimaging revealed signals that evolved differently during physically identical delays in the two environments, consistent with a dynamic and context-sensitive reappraisal of subjective value. This effect was observed in a region of ventromedial prefrontal cortex that is sensitive to subjective value in other contexts, demonstrating continuity between valuation mechanisms involved in discrete choice and in temporally extended decisions analogous to foraging. Our findings support a model in which voluntary persistence emerges from dynamic cost/benefit evaluation rather than from a control process that overrides valuation mechanisms. PMID:25849988

  16. Structure-Activity Relationship of Amino Acid Tunable Lipidated Norspermidine Conjugates: Disrupting Biofilms with Potent Activity against Bacterial Persisters.

    PubMed

    Konai, Mohini M; Adhikary, Utsarga; Samaddar, Sandip; Ghosh, Chandradhish; Haldar, Jayanta

    2015-12-16

    The emergence of bacterial resistance and biofilm associated infections has created a challenging situation in global health. In this present state of affairs where conventional antibiotics are falling short of being able to provide a solution to these problems, development of novel antibacterial compounds possessing the twin prowess of antibacterial and antibiofilm efficacy is imperative. Herein, we report a library of amino acid tunable lipidated norspermidine conjugates that were prepared by conjugating both amino acids and fatty acids with the amine functionalities of norspermidine through amide bond formation. These lipidated conjugates displayed potent antibacterial activity against various planktonic Gram-positive and Gram-negative bacteria including drug-resistant superbugs such as methicillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococcus faecium, and β-lactam-resistant Klebsiella pneumoniae. This class of nontoxic and fast-acting antibacterial molecules (capable of killing bacteria within 15 min) did not allow bacteria to develop resistance against them after several passages. Most importantly, an optimized compound in the series was also capable of killing metabolically inactive persisters and stationary phase bacteria. Additionally, this compound was capable of disrupting the preformed biofilms of S. aureus and E. coli. Therefore, this class of antibacterial conjugates have potential in tackling the challenging situation posed by both bacterial resistance as well as drug tolerance due to biofilm formation. PMID:26452096

  17. The Persistence of Erroneous Familiarity in an Epileptic Male: Challenging Perceptual Theories of Deja Vu Activation

    ERIC Educational Resources Information Center

    O'Connor, Akira R.; Moulin, Christopher J. A.

    2008-01-01

    We report the case of a 39-year-old, temporal lobe epileptic male, MH. Prior to complex partial seizure, experienced up to three times a day, MH often experiences an aura experienced as a persistent sensation of deja vu. Data-driven theories of deja vu formation suggest that partial familiarity for the perceived stimulus is responsible for the…

  18. Persistence of Cognitive Constructs Fostered by Hands-On Science Activities in Middle School Students

    ERIC Educational Resources Information Center

    Christensen, Rhonda; Knezek, Gerald; Tyler-Wood, Tandra; Gibson, David

    2013-01-01

    The purpose of this paper is to determine whether the changes that were found to occur pre- to post intervention in students' cognitive structures (Mills, 2013; Knezek, Christensen, Tyler-Wood, & Periathiruvadi, 2013) continued to persist two years later. Major findings were: a) semantic perception of science and STEM as a career became more…

  19. College Students' Goal Orientations, Situational Motivation and Effort/Persistence in Physical Activity Classes

    ERIC Educational Resources Information Center

    Gao, Zan; Podlog, Leslie W.; Harrison, Louis

    2012-01-01

    The purpose of this study was to examine relationships among college students' 2 x 2 goal orientations (mastery-approach [MAp], mastery-avoidance [MAv], performance-approach [PAp], performance-avoidance [PAv]), situational motivation (intrinsic motivation, identified regulation, external regulation and amotivation) and effort/persistence in…

  20. Severity of Dysfluency Correlates with Basal Ganglia Activity in Persistent Developmental Stuttering

    ERIC Educational Resources Information Center

    Giraud, Anne-Lise; Neumann, Katrin; Bachoud-Levi, Anne-Catherine; von Gudenberg, Alexander W.; Euler, Harald A.; Lanfermann, Heinrich; Preibisch, Christine

    2008-01-01

    Previous studies suggest that anatomical anomalies [Foundas, A. L., Bollich, A. M., Corey, D. M., Hurley, M., & Heilman, K. M. (2001). "Anomalous anatomy of speech-language areas in adults with persistent developmental stuttering." "Neurology," 57, 207-215; Foundas, A. L., Corey, D. M., Angeles, V., Bollich, A. M., Crabtree-Hartman, E., & Heilman,…

  1. Brain Activation Gradients in Ventrolateral Prefrontal Cortex Related to Persistence of ADHD in Adolescent Boys

    ERIC Educational Resources Information Center

    Schulz, Kurt P.; Newcorn, Jeffrey H.; Fan, Jin; Tang, Cheuk Y.; Halperin, Jeffrey M.

    2005-01-01

    Objective: To explore the possible role that functional abnormalities of the prefrontal cortex and basal ganglia play in the persistence of attention-deficit/hyperactivity disorder (ADHD) in adolescents aged 15 to 19 years. Method: Ten male adolescents who were diagnosed with ADHD during childhood were grouped into those who continued to meet full…

  2. History dependence of rate covariation between neurons during persistent activity in an oculomotor integrator.

    PubMed

    Aksay, Emre; Major, Guy; Goldman, Mark S; Baker, Robert; Seung, H Sebastian; Tank, David W

    2003-11-01

    Persistent firing in response to a brief stimulus is a neural correlate of short-term memory in a variety of systems. In the oculomotor neural integrator, persistent firing that encodes eye position is maintained in response to transient saccadic eye-velocity commands. To a first approximation, firing rates in the integrator vary linearly with eye position. Thus, viewed across many cells, the pattern of persistent firing in the integrator may be constrained to a unique line of stable states. Here this idea was tested by examining the relationship between firing rates of simultaneously recorded neurons. Paired recordings were obtained in awake goldfish from neurons in hindbrain area I, an essential part of the horizontal eye-position integrator. During spontaneous eye movements consisting of sequential fixations at different horizontal positions, the pair relationship between the majority of cells on the same side of the integrator was not unique: for a given rate of one cell, the rate of the paired cell assumed different values that depended systematically on the preceding saccade history. This finding suggests that the set of persistent firing states that encode eye position is not constrained to a unique line, and that models with stable states restricted to a such a line need to be modified accordingly.

  3. New paradigms for understanding and step changes in treating active and chronic, persistent apicomplexan infections

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Toxoplasma gondii, the most common parasitic infection of the human brain and eye, persists across lifetimes, can progressively damage sight, and is currently incurable. New, curative medicines are needed urgently. Herein, we developed novel models to facilitate drug development: EGS strain T. gondi...

  4. Urocortin 2 stimulates nitric oxide production in ventricular myocytes via Akt- and PKA-mediated phosphorylation of eNOS at serine 1177

    PubMed Central

    Walther, Stefanie; Pluteanu, Florentina; Renz, Susanne; Nikonova, Yulia; Maxwell, Joshua T.; Yang, Li-Zhen; Schmidt, Kurt; Edwards, Joshua N.; Wakula, Paulina; Groschner, Klaus; Maier, Lars S.; Spiess, Joachim; Blatter, Lothar A.; Pieske, Burkert

    2014-01-01

    Urocortin 2 (Ucn2) is a cardioactive peptide exhibiting beneficial effects in normal and failing heart. In cardiomyocytes, it elicits cAMP- and Ca2+-dependent positive inotropic and lusitropic effects. We tested the hypothesis that, in addition, Ucn2 activates cardiac nitric oxide (NO) signaling and elucidated the underlying signaling pathways and mechanisms. In isolated rabbit ventricular myocytes, Ucn2 caused concentration- and time-dependent increases in phosphorylation of Akt (Ser473, Thr308), endothelial NO synthase (eNOS) (Ser1177), and ERK1/2 (Thr202/Tyr204). ERK1/2 phosphorylation, but not Akt and eNOS phosphorylation, was suppressed by inhibition of MEK1/2. Increased Akt phosphorylation resulted in increased Akt kinase activity and was mediated by corticotropin-releasing factor 2 (CRF2) receptors (astressin-2B sensitive). Inhibition of phosphatidylinositol 3-kinase (PI3K) diminished both Akt as well as eNOS phosphorylation mediated by Ucn2. Inhibition of protein kinase A (PKA) reduced Ucn2-induced phosphorylation of eNOS but did not affect the increase in phosphorylation of Akt. Conversely, direct receptor-independent elevation of cAMP via forskolin increased phosphorylation of eNOS but not of Akt. Ucn2 increased intracellular NO concentration ([NO]i), [cGMP], [cAMP], and cell shortening. Inhibition of eNOS suppressed the increases in [NO]i and cell shortening. When both PI3K-Akt and cAMP-PKA signaling were inhibited, the Ucn2-induced increases in [NO]i and cell shortening were attenuated. Thus, in rabbit ventricular myocytes, Ucn2 causes activation of cAMP-PKA, PI3K-Akt, and MEK1/2-ERK1/2 signaling. The MEK1/2-ERK1/2 pathway is not required for stimulation of NO signaling in these cells. The other two pathways, cAMP-PKA and PI3K-Akt, converge on eNOS phosphorylation at Ser1177 and result in pronounced and sustained cellular NO production with subsequent stimulation of cGMP signaling. PMID:25015964

  5. Keeping women active: an examination of the impacts of self-efficacy, intrinsic motivation, and leadership on women's persistence in physical activity.

    PubMed

    Lloyd, Kathleen M; Little, Donna E

    2010-10-01

    Physical inactivity in women is a worldwide problem that has not only been well-documented but has provoked much government concern and policy activity. However, an even more important issue is encouraging women's persistence in physical activity. The purpose of this study was to examine the links between women's experiences of participation in a government-funded physical activity festival, their intentions to continue participation, and their participation behavior six months after the festival. Results from semi-structured, in-depth interviews with 20 women revealed that enhanced self-efficacy, intrinsic motivation, and supportive leadership had motivated the women's future intentions to participate. Follow-up surveys showed their levels of interest and participation in physical activity had been maintained. These results enhance our understanding of the relationship between key outcomes of women's physical activity participation and their persistence in physical activity.

  6. Persistent Hepatitis C Virus Infection Impairs Ribavirin Antiviral Activity through Clathrin-Mediated Trafficking of Equilibrative Nucleoside Transporter 1

    PubMed Central

    Panigrahi, Rajesh; Chandra, Partha K.; Ferraris, Pauline; Kurt, Ramazan; Song, Kyoungsub; Garry, Robert F.; Reiss, Krzysztof; Coe, Imogen R.; Furihata, Tomomi; Balart, Luis A.; Wu, Tong

    2014-01-01

    ABSTRACT Ribavirin (RBV) continues to be an important component of interferon-free hepatitis C treatment regimens, as RBV alone does not inhibit hepatitis C virus (HCV) replication effectively; the reason for this ineffectiveness has not been established. In this study, we investigated the RBV resistance mechanism using a persistently HCV-infected cell culture system. The antiviral activity of RBV against HCV was progressively impaired in the persistently infected culture, whereas interferon lambda 1 (IFN-λ1), a type III IFN, showed a strong antiviral response and induced viral clearance. We found that HCV replication in persistently infected cultures induces an autophagy response that impairs RBV uptake by preventing the expression of equilibrative nucleoside transporter 1 (ENT1). The Huh-7.5 cell line treated with an autophagy inducer, Torin 1, downregulated membrane expression of ENT1 and terminated RBV uptake. In contrast, the autophagy inhibitors hydroxychloroquine (HCQ), 3-methyladenine (3-MA), and bafilomycin A1 (BafA1) prevented ENT1 degradation and enhanced RBV antiviral activity. The HCV-induced autophagy response, as well as treatment with Torin 1, degrades clathrin heavy chain expression in a hepatoma cell line. Reduced expression of the clathrin heavy chain by HCV prevents ENT1 recycling to the plasma membrane and forces ENT1 to the lysosome for degradation. This study provides a potential mechanism for the impairment of RBV antiviral activity in persistently HCV-infected cell cultures and suggests that inhibition of the HCV-induced autophagy response could be used as a strategy for improving RBV antiviral activity against HCV infection. IMPORTANCE The results from this work will allow a review of the competing theories of antiviral therapy development in the field of HCV virology. Ribavirin (RBV) remains an important component of interferon-free hepatitis C treatment regimens. The reason why RBV alone does not inhibit HCV replication effectively has

  7. Infection of lymphocytes by a virus that aborts cytotoxic T lymphocyte activity and establishes persistent infection

    PubMed Central

    1991-01-01

    For viruses to establish persistent infections in their hosts, they must possess some mechanism for evading clearance by the immune system. When inoculated into adult immunocompetent mice, wild-type lymphocytic choriomeningitis virus (LCMV ARM) induces a CD8(+)-mediated cytotoxic T lymphocyte (CTL) response that clears the infection within 7-14 d (CTL+ [P-]). By contrast, variant viruses isolated from lymphoid tissues of persistently infected mice fail to induce a CTL response and are thus able to establish a persistent infection in adult mice (CTL- [P+]). This report compares the interaction of CTL+ (P-) and CTL- (P+) viruses with cells of the immune system. Both types of virus initially bind to 2-4% of CD4+ and CD8+ T lymphocytes and replicate within cells of both subsets. The replication of CTL- (P+) and CTL+ (P-) viruses in lymphocytes in vivo is similar for the first 5 d after initiating infection. Thereafter, in mice infected with CTL- (P+) variants, lymphocytes retain viral genetic information, and infectious virus can be recovered throughout the animals' lives. In contrast, when adult mice are infected with wild-type CTL+ (P-) LCMV ARM, virus is not recovered from lymphocytes for greater than 7 d after infection. A CD8(+)-mediated anti-LCMV CTL response is induced in such mice. Clearance of infected lymphocytes is produced by these LCMV-specific CTLs, as shown by their ability to lyse lymphocytes expressing LCMV determinants in vitro and the fact that depletion of CD8+ lymphocytes before infection with CTL+ (P-) viruses results in levels of infected lymphocytes similar to those found in undepleted CTL- (P+)-infected mice. Hence, CTL-mediated lysis of T lymphocytes carrying infectious virus is a critical factor determining whether virus persists or the infection is terminated. PMID:1905339

  8. Persistent neural activity in auditory cortex is related to auditory working memory in humans and nonhuman primates.

    PubMed

    Huang, Ying; Matysiak, Artur; Heil, Peter; König, Reinhard; Brosch, Michael

    2016-01-01

    Working memory is the cognitive capacity of short-term storage of information for goal-directed behaviors. Where and how this capacity is implemented in the brain are unresolved questions. We show that auditory cortex stores information by persistent changes of neural activity. We separated activity related to working memory from activity related to other mental processes by having humans and monkeys perform different tasks with varying working memory demands on the same sound sequences. Working memory was reflected in the spiking activity of individual neurons in auditory cortex and in the activity of neuronal populations, that is, in local field potentials and magnetic fields. Our results provide direct support for the idea that temporary storage of information recruits the same brain areas that also process the information. Because similar activity was observed in the two species, the cellular bases of some auditory working memory processes in humans can be studied in monkeys. PMID:27438411

  9. Stimulation of Ebola virus production from persistent infection through activation of the Ras/MAPK pathway.

    PubMed

    Strong, James E; Wong, Gary; Jones, Shane E; Grolla, Allen; Theriault, Steven; Kobinger, Gary P; Feldmann, Heinz

    2008-11-18

    Human infections with Ebola virus (EBOV) result in a deadly viral disease known as Ebola hemorrhagic fever. Up to 90% of infected patients die, and there is no available treatment or vaccine. The sporadic human outbreaks are believed to result when EBOV "jumps" from an infected animal to a person and is subsequently transmitted between persons by direct contact with infected blood or body fluids. This study was undertaken to investigate the mechanism by which EBOV can persistently infect and then escape from model cell and animal reservoir systems. We report a model system in which infection of mouse and bat cell lines with EBOV leads to persistence, which can be broken with low levels of lipopolysaccharide or phorbol-12-myristate-13-acetate (PMA). This reactivation depends on the Ras/MAPK pathway through inhibition of RNA-dependent protein kinase and eukaryotic initiation factor 2alpha phosphorylation and occurs at the level of protein synthesis. EBOV also can be evoked from mice 7 days after infection by PMA treatment, indicating that a similar mechanism occurs in vivo. Our findings suggest that EBOV may persist in nature through subclinical infection of a reservoir species, such as bats, and that appropriate physiological stimulation may result in increased replication and transmission to new hosts. Identification of a presumptive mechanism responsible for EBOV emergence from its reservoir underscores the "hit-and-run" nature of the initiation of human and/or nonhuman primate EBOV outbreaks and may provide insight into possible countermeasures to interfere with transmission. PMID:18981410

  10. The effects of PBDE-209 exposure during pregnancy on placental ET-1 and eNOS expression and the birth weight of offspring.

    PubMed

    Du, Peili; Li, Zhihua; Du, Lili; Zhang, Huili; Zhou, Yanmei; Sun, Wen; Xiao, Xue; He, Yutian; Sun, Bin; Yu, Yanhong; Chen, Dunjin

    2015-06-01

    Decabrominated diphenyl ether (PBDE-209) is a persistent organic pollutant. Gestational exposure to PBDE-209 can accumulate in pregnant women and fetuses via the placenta and umbilical cord, affecting perinatal outcome. In this study, pregnant Sprague-Dawley (SD) rats were randomly divided into five groups and intragastrically administered peanut oil (vehicle) 1, 5 and 10mg/kg by body weight (b.w.) of PBDE-209, or nothing (control) from day 0 (G0) to day 21 (G21) gestation, respectively. Placental samples were collected on G21 by cesarean section. The mRNA and protein expressions of ET-1, eNOS and iNOS in the placenta were examined using qRT-PCR and Western blot, respectively. Total nitric oxide (NO) in the placenta was measured using a specific ELISA kit. Compared with the control and vehicle groups, the mRNA expression of ET-1 and iNOS in the placenta was gradually and significantly increased after exposure to increasing concentrations of PBDE-209 (P<0.05), while the mRNA level of eNOS in the placenta was gradually and significantly reduced after exposure to increasing concentrations of PBDE-209 (P<0.05). The expression trends of ET-1, eNOS and iNOS proteins were consistent with those of mRNA expression. Interestingly, the production of total NO was significantly increased after exposure to 5 and 10mg/kg b.w. PBDE-209 (P<0.05). Finally, the birth weight of the offspring rats was significantly reduced after maternal exposure to 5 and 10 mg/kg b.w. PBDE-209 compared with the control and vehicle groups (P<0.05). These results suggest that PBDE-209 exposure during pregnancy upregulates ET-1 and iNOS expression, but decreases eNOS expression in the placenta, as well as reduces the birth weight of offspring.

  11. Increased IFNα activity and differential antibody response in patients with a history of Lyme disease and persistent cognitive deficits.

    PubMed

    Jacek, Elzbieta; Fallon, Brian A; Chandra, Abhishek; Crow, Mary K; Wormser, Gary P; Alaedini, Armin

    2013-02-15

    Following antibiotic treatment for Lyme disease, some patients report persistent or relapsing symptoms of pain, fatigue, and/or cognitive deficits. Factors other than active infection, including immune abnormalities, have been suggested, but few clues regarding mechanism have emerged. Furthermore, the effect of antibiotic treatment on immune response in affected individuals remains unknown. In this study, a longitudinal analysis of specific immune markers of interest was carried out in patients with a history of Lyme disease and persistent objective memory impairment, prior to and following treatment with either ceftriaxone or placebo. IFNα activity was measured by detection of serum-induced changes in specific target genes, using a functional cell-based assay and quantitative real-time PCR. Level and pattern of antibody reactivity to brain antigens and to Borrelia burgdorferi proteins were analyzed by ELISA and immunoblotting. Sera from the patient cohort induced significantly higher expression of IFIT1 and IFI44 target genes than those from healthy controls, indicating increased IFNα activity. Antibody reactivity to specific brain and borrelial proteins was significantly elevated in affected patients. IFNα activity and antibody profile did not change significantly in response to ceftriaxone. The heightened antibody response implies enhanced immune stimulation, possibly due to prolonged exposure to the organism prior to the initial diagnosis and antibiotic treatment of Lyme disease. The increase in IFNα activity is suggestive of a mechanism contributing to the ongoing neuropsychiatric symptoms. PMID:23141748

  12. Increased IFNα activity and differential antibody response in patients with a history of Lyme disease and persistent cognitive deficits.

    PubMed

    Jacek, Elzbieta; Fallon, Brian A; Chandra, Abhishek; Crow, Mary K; Wormser, Gary P; Alaedini, Armin

    2013-02-15

    Following antibiotic treatment for Lyme disease, some patients report persistent or relapsing symptoms of pain, fatigue, and/or cognitive deficits. Factors other than active infection, including immune abnormalities, have been suggested, but few clues regarding mechanism have emerged. Furthermore, the effect of antibiotic treatment on immune response in affected individuals remains unknown. In this study, a longitudinal analysis of specific immune markers of interest was carried out in patients with a history of Lyme disease and persistent objective memory impairment, prior to and following treatment with either ceftriaxone or placebo. IFNα activity was measured by detection of serum-induced changes in specific target genes, using a functional cell-based assay and quantitative real-time PCR. Level and pattern of antibody reactivity to brain antigens and to Borrelia burgdorferi proteins were analyzed by ELISA and immunoblotting. Sera from the patient cohort induced significantly higher expression of IFIT1 and IFI44 target genes than those from healthy controls, indicating increased IFNα activity. Antibody reactivity to specific brain and borrelial proteins was significantly elevated in affected patients. IFNα activity and antibody profile did not change significantly in response to ceftriaxone. The heightened antibody response implies enhanced immune stimulation, possibly due to prolonged exposure to the organism prior to the initial diagnosis and antibiotic treatment of Lyme disease. The increase in IFNα activity is suggestive of a mechanism contributing to the ongoing neuropsychiatric symptoms.

  13. TAML activator/peroxide-catalyzed facile oxidative degradation of the persistent explosives trinitrotoluene and trinitrobenzene in micellar solutions.

    PubMed

    Kundu, Soumen; Chanda, Arani; Khetan, Sushil K; Ryabov, Alexander D; Collins, Terrence J

    2013-05-21

    TAML activators are well-known for their ability to activate hydrogen peroxide to oxidize persistent pollutants in water. The trinitroaromatic explosives, 2,4,6-trinitrotoluene (TNT) and 1,3,5-trinitrobenzene (TNB), are often encountered together as persistent, toxic pollutants. Here we show that an aggressive TAML activator with peroxides boosts the effectiveness of the known surfactant/base promoted breakdown of TNT and transforms the surfactant induced nondestructive binding of base to TNB into an extensive multistep degradation process. Treatment of basic cationic surfactant solutions of either TNT or TNB with TAML/peroxide (hydrogen peroxide and tert-butylhydroperoxide, TBHP) gave complete pollutant removal for both in <1 h with >75% of the nitrogen and ≥20% of the carbon converted to nitrite/nitrate and formate, respectively. For TNT, the TAML advantage is to advance the process toward mineralization. Basic surfactant solutions of TNB gave the colored solutions typical of known Meisenheimer complexes which did not progress to degradation products over many hours. However with added TAML activator, the color was bleached quickly and the TNB starting compound was degraded extensively toward minerals within an hour. A slower surfactant-free TAML activator/peroxide process also degrades TNT/TNB effectively. Thus, TAML/peroxide amplification effectively advances TNT and TNB water treatment giving reason to explore the environmental applicability of the approach.

  14. Enolase 1 (ENO1) and protein disulfide-isomerase associated 3 (PDIA3) regulate Wnt/β-catenin-driven trans-differentiation of murine alveolar epithelial cells

    PubMed Central

    Mutze, Kathrin; Vierkotten, Sarah; Milosevic, Jadranka; Eickelberg, Oliver; Königshoff, Melanie

    2015-01-01

    ABSTRACT The alveolar epithelium represents a major site of tissue destruction during lung injury. It consists of alveolar epithelial type I (ATI) and type II (ATII) cells. ATII cells are capable of self-renewal and exert progenitor function for ATI cells upon alveolar epithelial injury. Cell differentiation pathways enabling this plasticity and allowing for proper repair, however, are poorly understood. Here, we applied proteomics, expression analysis and functional studies in primary murine ATII cells to identify proteins and molecular mechanisms involved in alveolar epithelial plasticity. Mass spectrometry of cultured ATII cells revealed a reduction of carbonyl reductase 2 (CBR2) and an increase in enolase 1 (ENO1) and protein disulfide-isomerase associated 3 (PDIA3) protein expression during ATII-to-ATI cell trans-differentiation. This was accompanied by increased Wnt/β-catenin signaling, as analyzed by qRT-PCR and immunoblotting. Notably, ENO1 and PDIA3, along with T1α (podoplanin; an ATI cell marker), exhibited decreased protein expression upon pharmacological and molecular Wnt/β-catenin inhibition in cultured ATII cells, whereas CBR2 levels were stabilized. Moreover, we analyzed primary ATII cells from mice with bleomycin-induced lung injury, a model exhibiting activated Wnt/β-catenin signaling in vivo. We observed reduced CBR2 significantly correlating with surfactant protein C (SFTPC), whereas ENO1 and PDIA3 along with T1α were increased in injured ATII cells. Finally, siRNA-mediated knockdown of ENO1, as well as PDIA3, in primary ATII cells led to reduced T1α expression, indicating diminished cell trans-differentiation. Our data thus identified proteins involved in ATII-to-ATI cell trans-differentiation and suggest a Wnt/β-catenin-driven functional role of ENO1 and PDIA3 in alveolar epithelial cell plasticity in lung injury and repair. PMID:26035385

  15. Heme changes HIF-α, eNOS and nitrite production in HUVECs after simvastatin, HU, and ascorbic acid therapies.

    PubMed

    da Guarda, Caroline C; Santiago, Rayra P; Pitanga, Thassila N; Santana, Sanzio S; Zanette, Dalila L; Borges, Valéria M; Goncalves, Marilda S

    2016-07-01

    The sickle cell disease (SCD) is a hemolytic genetic anemia characterized by free heme and hemoglobin release into intravascular spaces, with endothelial activation. Heme is a proinflammatory molecule able to directly activate vascular endothelium, thus, endothelial dysfunction and vascular disease are major chronic events described in SCD. The aim of this study was to evaluate the production of endothelial nitric oxide synthase (eNOS), nitrite and hypoxia inducible factor alpha (HIF-α) in HUVECs (human umbilical vein endothelial cells) activated by heme in response to simvastatin, hydroxyurea (HU), and ascorbic acid therapies. eNOS and HIF-α production were evaluated by ELISA and nitrite was measured by the Griess technique. The production of HIF-α increased when the cells were stimulated by heme (p<0.01), while treatment with HU and simvastatin reduced the production (p<0.01), and treatment with ascorbic acid increased HIF-1a production by the cells (p<0.01). Heme increased eNOS production, (p<0.01) but showed a heterogeneous pattern, and the lowest concentrations of all the treatments reduced the enzyme production (p<0.01). The nitrite production by HUVECs was enhanced by stimulation with heme (p<0.001) and was reduced by treatment with HU (p<0.001), ascorbic acid (p<0.001) and simvastatin (p<0.01). In summary, our results suggest that the hemolytic vascular microenvironment in SCD requires different therapeutic approaches to promote clinical improvement, and that a combination of therapies may be a viable strategy for treating patients.

  16. Persistent activation of DNA damage signaling in response to complex mixtures of PAHs in air particulate matter

    SciTech Connect

    Jarvis, Ian W.H.; Bergvall, Christoffer; Bottai, Matteo; Westerholm, Roger; Stenius, Ulla; Dreij, Kristian

    2013-02-01

    Complex mixtures of polycyclic aromatic hydrocarbons (PAHs) are present in air particulate matter (PM) and have been associated with many adverse human health effects including cancer and respiratory disease. However, due to their complexity, the risk of exposure to mixtures is difficult to estimate. In the present study the effects of binary mixtures of benzo[a]pyrene (BP) and dibenzo[a,l]pyrene (DBP) and complex mixtures of PAHs in urban air PM extracts on DNA damage signaling was investigated. Applying a statistical model to the data we observed a more than additive response for binary mixtures of BP and DBP on activation of DNA damage signaling. Persistent activation of checkpoint kinase 1 (Chk1) was observed at significantly lower BP equivalent concentrations in air PM extracts than BP alone. Activation of DNA damage signaling was also more persistent in air PM fractions containing PAHs with more than four aromatic rings suggesting larger PAHs contribute a greater risk to human health. Altogether our data suggests that human health risk assessment based on additivity such as toxicity equivalency factor scales may significantly underestimate the risk of exposure to complex mixtures of PAHs. The data confirms our previous findings with PAH-contaminated soil (Niziolek-Kierecka et al., 2012) and suggests a possible role for Chk1 Ser317 phosphorylation as a biological marker for future analyses of complex mixtures of PAHs. -- Highlights: ► Benzo[a]pyrene (BP), dibenzo[a,l]pyrene (DBP) and air PM PAH extracts were compared. ► Binary mixture of BP and DBP induced a more than additive DNA damage response. ► Air PM PAH extracts were more potent than toxicity equivalency factor estimates. ► Larger PAHs (> 4 rings) contribute more to the genotoxicity of PAHs in air PM. ► Chk1 is a sensitive marker for persistent activation of DNA damage signaling from PAH mixtures.

  17. The Fatty Acid Signaling Molecule cis-2-Decenoic Acid Increases Metabolic Activity and Reverts Persister Cells to an Antimicrobial-Susceptible State

    PubMed Central

    Morozov, Aleksey; Planzos, Penny; Zelaya, Hector M.

    2014-01-01

    Persister cells, which are tolerant to antimicrobials, contribute to biofilm recalcitrance to therapeutic agents. In turn, the ability to kill persister cells is believed to significantly improve efforts in eradicating biofilm-related, chronic infections. While much research has focused on elucidating the mechanism(s) by which persister cells form, little is known about the mechanism or factors that enable persister cells to revert to an active and susceptible state. Here, we demonstrate that cis-2-decenoic acid (cis-DA), a fatty acid signaling molecule, is able to change the status of Pseudomonas aeruginosa and Escherichia coli persister cells from a dormant to a metabolically active state without an increase in cell number. This cell awakening is supported by an increase of the persister cells' respiratory activity together with changes in protein abundance and increases of the transcript expression levels of several metabolic markers, including acpP, 16S rRNA, atpH, and ppx. Given that most antimicrobials target actively growing cells, we also explored the effect of cis-DA on enhancing antibiotic efficacy in killing persister cells due to their inability to keep a persister cell state. Compared to antimicrobial treatment alone, combinational treatments of persister cell subpopulations with antimicrobials and cis-DA resulted in a significantly greater decrease in cell viability. In addition, the presence of cis-DA led to a decrease in the number of persister cells isolated. We thus demonstrate the ability of a fatty acid signaling molecule to revert bacterial cells from a tolerant phenotype to a metabolically active, antimicrobial-sensitive state. PMID:25192989

  18. On the application of ENO scheme with subcell resolution to conservation laws with stiff source terms

    NASA Technical Reports Server (NTRS)

    Chang, Shih-Hung

    1991-01-01

    Two approaches are used to extend the essentially non-oscillatory (ENO) schemes to treat conservation laws with stiff source terms. One approach is the application of the Strang time-splitting method. Here the basic ENO scheme and the Harten modification using subcell resolution (SR), ENO/SR scheme, are extended this way. The other approach is a direct method and a modification of the ENO/SR. Here the technique of ENO reconstruction with subcell resolution is used to locate the discontinuity within a cell and the time evolution is then accomplished by solving the differential equation along characteristics locally and advancing in the characteristic direction. This scheme is denoted ENO/SRCD (subcell resolution - characteristic direction). All the schemes are tested on the equation of LeVeque and Yee (NASA-TM-100075, 1988) modeling reacting flow problems. Numerical results show that these schemes handle this intriguing model problem very well, especially with ENO/SRCD which produces perfect resolution at the discontinuity.

  19. Stochastic induction of persister cells by HipA through (p)ppGpp-mediated activation of mRNA endonucleases.

    PubMed

    Germain, Elsa; Roghanian, Mohammad; Gerdes, Kenn; Maisonneuve, Etienne

    2015-04-21

    The model organism Escherichia coli codes for at least 11 type II toxin-antitoxin (TA) modules, all implicated in bacterial persistence (multidrug tolerance). Ten of these encode messenger RNA endonucleases (mRNases) inhibiting translation by catalytic degradation of mRNA, and the 11th module, hipBA, encodes HipA (high persister protein A) kinase, which inhibits glutamyl tRNA synthetase (GltX). In turn, inhibition of GltX inhibits translation and induces the stringent response and persistence. Previously, we presented strong support for a model proposing (p)ppGpp (guanosine tetra and penta-phosphate) as the master regulator of persistence. Stochastic variation of [(p)ppGpp] in single cells induced TA-encoded mRNases via a pathway involving polyphosphate and Lon protease. Polyphosphate activated Lon to degrade all known type II antitoxins of E. coli. In turn, the activated mRNases induced persistence and multidrug tolerance. However, even though it was known that activation of HipA stimulated (p)ppGpp synthesis, our model did not explain how hipBA induced persistence. Here we show that, in support of and consistent with our initial model, HipA-induced persistence depends not only on (p)ppGpp but also on the 10 mRNase-encoding TA modules, Lon protease, and polyphosphate. Importantly, observations with single cells convincingly show that the high level of (p)ppGpp caused by activation of HipA does not induce persistence in the absence of TA-encoded mRNases. Thus, slow growth per se does not induce persistence in the absence of TA-encoded toxins, placing these genes as central effectors of bacterial persistence.

  20. The combinatorial activation of the PI3K and Ras/MAPK pathways is sufficient for aggressive tumor formation, while individual pathway activation supports cell persistence

    PubMed Central

    Thompson, Keyata N.; Whipple, Rebecca A.; Yoon, Jennifer R.; Lipsky, Michael; Charpentier, Monica S.; Boggs, Amanda E.; Chakrabarti, Kristi R.; Bhandary, Lekhana; Hessler, Lindsay K.; Martin, Stuart S.; Vitolo, Michele I.

    2015-01-01

    A high proportion of human tumors maintain activation of both the PI3K and Ras/MAPK pathways. In basal-like breast cancer (BBC), PTEN expression is decreased/lost in over 50% of cases, leading to aberrant activation of the PI3K pathway. Additionally, BBC cell lines and tumor models have been shown to exhibit an oncogenic Ras-like gene transcriptional signature, indicating activation of the Ras/MAPK pathway. To directly test how the PI3K and Ras/MAPK pathways contribute to tumorigenesis, we deleted PTEN and activated KRas within non-tumorigenic MCF-10A breast cells. Neither individual mutation was sufficient to promote tumorigenesis, but the combination promoted robust tumor growth in mice. However, in vivo bioluminescence reveals that each mutation has the ability to promote a persistent phenotype. Inherent in the concept of tumor cell dormancy, a stage in which residual disease is present but remains asymptomatic, viable cells with each individual mutation can persist in vivo during a period of latency. The persistent cells were excised from the mice and showed increased levels of the cell cycle arrest proteins p21 and p27 compared to the aggressively growing PTEN−/−KRAS(G12V) cells. Additionally, when these persistent cells were placed into growth-promoting conditions, they were able to re-enter the cell cycle and proliferate. These results highlight the potential for either PTEN loss or KRAS activation to promote cell survival in vivo, and the unique ability of the combined mutations to yield rapid tumor growth. This could have important implications in determining recurrence risk and disease progression in tumor subtypes where these mutations are common. PMID:26497685

  1. The combinatorial activation of the PI3K and Ras/MAPK pathways is sufficient for aggressive tumor formation, while individual pathway activation supports cell persistence.

    PubMed

    Thompson, Keyata N; Whipple, Rebecca A; Yoon, Jennifer R; Lipsky, Michael; Charpentier, Monica S; Boggs, Amanda E; Chakrabarti, Kristi R; Bhandary, Lekhana; Hessler, Lindsay K; Martin, Stuart S; Vitolo, Michele I

    2015-11-01

    A high proportion of human tumors maintain activation of both the PI3K and Ras/MAPK pathways. In basal-like breast cancer (BBC), PTEN expression is decreased/lost in over 50% of cases, leading to aberrant activation of the PI3K pathway. Additionally, BBC cell lines and tumor models have been shown to exhibit an oncogenic Ras-like gene transcriptional signature, indicating activation of the Ras/MAPK pathway. To directly test how the PI3K and Ras/MAPK pathways contribute to tumorigenesis, we deleted PTEN and activated KRas within non-tumorigenic MCF-10A breast cells. Neither individual mutation was sufficient to promote tumorigenesis, but the combination promoted robust tumor growth in mice. However, in vivo bioluminescence reveals that each mutation has the ability to promote a persistent phenotype. Inherent in the concept of tumor cell dormancy, a stage in which residual disease is present but remains asymptomatic, viable cells with each individual mutation can persist in vivo during a period of latency. The persistent cells were excised from the mice and showed increased levels of the cell cycle arrest proteins p21 and p27 compared to the aggressively growing PTEN-/-KRAS(G12V) cells. Additionally, when these persistent cells were placed into growth-promoting conditions, they were able to re-enter the cell cycle and proliferate. These results highlight the potential for either PTEN loss or KRAS activation to promote cell survival in vivo, and the unique ability of the combined mutations to yield rapid tumor growth. This could have important implications in determining recurrence risk and disease progression in tumor subtypes where these mutations are common. PMID:26497685

  2. Molecular characterisation and expression profiling of the ENO1 gene in the ovarian follicle of the Sichuan white goose.

    PubMed

    Kang, Bo; Jiang, Dong Mei; Bai, Lin; He, Hui; Ma, Rong

    2014-01-01

    The ENO1 gene encodes a multifunctional enzyme that has been identified as a key component of the glycolytic pathway. Our previous studies demonstrated that ENO1 gene expression was higher in the ovaries of laying geese compared with prelaying geese. However, the molecular characterisation and expression profiling of the ENO1 gene in geese tissues and ovarian follicles remain to be determined. In this study, ENO1 cDNA (1,445 bp long) of the Sichuan white goose was cloned and characterised. The ORF of ENO1 cDNA is 1,305 bp in length and encodes a 434 amino acid protein with a molecular weight of 47.27 kDa. ENO1 expression in all of the examined tissues was the highest in spleen and the lowest in breast muscle. High expression of ENO1 appeared in the kidney, liver, adrenal gland, and retina. With increasing follicle growth, ENO1 gene expression began to decrease from the small white follicle to F5, which was followed by a sharp increase in expression in F4 and then a gradual decrease in expression from F3 to F1. Furthermore, in the postovulatory follicles (POF), the levels of ENO1 gene expression decreased gradually from POF1 to POF4. In conclusion, the ENO1 transcript was widely distributed in various tissues of the Sichuan white goose, but ENO1 expression was tissue-specific. Furthermore, the results of the ENO1 expression profiling of ovarian follicles suggest that ENO1 may play an important dual role in the progress of follicular development, where ENO1 acts as a glycolytic enzyme and also mediates apoptosis.

  3. Improved ability to perform strenuous activities after treatment with fluticasone propionate/salmeterol combination in patients with persistent asthma.

    PubMed

    Nathan, Robert A; Dorinsky, Paul; Rosenzweig, Jacqueline R Carranza; Shah, Tushar; Edin, Heather; Prillaman, Barbara

    2003-01-01

    Patients with asthma experience disruptions in usual activities that can impair their quality of life, and in patients whose daily routine involves an active lifestyle, these disruptions can be severe. We assessed the patient-perceived effect of treatment with fluticasone propionate/salmeterol combination (FSC), compared with fluticasone propionate (FP) or salmeterol (SAL) alone, on activity limitations, particularly strenuous physical activities. The Asthma Quality of Life Questionnaire (AQLQ) was administered in two 12-week, randomized, double-blind, placebo-controlled trials comparing FSC 100/50 or 250/50 microg twice daily vs. the individual components alone in 686 adults and adolescents with asthma. In one study, patients were stratified by prior treatment [low to medium doses of inhaled corticosteroids (ICS) or SAL], and in the other study, all patients were previously treated with medium to high doses of ICS. Patients prospectively identified five activities they performed regularly and were asked how these activities were limited by their asthma. The effect of randomized treatment on strenuous activities (e.g., aerobics, cycling, hiking, and basketball) was assessed. In both studies, treatment with FSC resulted in clinically meaningful improvements (i.e., change in AQLQ of > or = 0.5) and was statistically significantly better than SAL in both studies and FP in one study. Treatment of the two main components of asthma--inflammation and bronchoconstriction--with FSC results in clinically meaningful improvements in the ability of patients with persistent asthma to perform not only their usual activities but also strenuous activities.

  4. Fifth Grade Students' Experiences Participating in Active Gaming in Physical Education: The Persistence to Game

    ERIC Educational Resources Information Center

    Hansen, Lisa; Sanders, Steve

    2010-01-01

    Although video games are often associated with sedentary behaviors, active gaming is a new genre that requires children to become physically active while playing the games. In this study six fifth grade students' experiences participating in active gaming in eight-week physical education classes were explored. Qualitative methods of interviews,…

  5. Interstitial chromatin alteration causes persistent p53 activation involved in the radiation-induced senescence-like growth arrest

    SciTech Connect

    Suzuki, Masatoshi; Suzuki, Keiji; Kodama, Seiji; Watanabe, Masami . E-mail: nabe@rri.kyoto-u.ac.jp

    2006-02-03

    Various stresses including ionizing radiation give normal human fibroblasts a phenotype of senescence-like growth arrest (SLGA), manifested by p53-dependent irreversible G1 arrest. To determine the mechanism of persistent activation of p53, we examined phosphorylated Ataxia telangiectasia mutated (ATM) and phosphorylated histone H2AX foci formation after X-irradiation. Although the multiple tiny foci, detected soon after (<30 min) irradiation, gradually disappeared, some of these foci changed to large foci and persisted for 5 days. Large foci containing phosphorylated ATM and {gamma}-H2AX co-localized and foci with p53 phosphorylated at serine 15 also showed the same distribution. Interestingly, the signals obtained by telomere fluorescence in situ hybridization (FISH) assay did not co-localize with 90% of the large foci. Our results indicate that chromatin alteration in interstitial chromosomal regions is the most likely cause of continuous activation of p53, which results in the induction of SLGA by ionizing radiation.

  6. A Comparison of ENO and TVD Schemes for the Computation of Shock-Turbulence Interaction

    NASA Astrophysics Data System (ADS)

    Hannappel, Ralf; Hauser, Thomas; Friedrich, Rainer

    1995-10-01

    A quantitative analysis of solutions to the Euler equations of fluid dynamis with the MUSCL, ENO-Harten, and efficient ENO-Shu algorithms is performed. Investigations of different test problems in one and two dimensions are presented. These are chosen as to model the shock-turbulence interaction in fluid dynamical systems. The notion of subcell resolution developed by Harten for the ENO schemes clearly improves the solution in one dimension; however, the effect is less prominent in a Strang-type extension to two dimensions. Our results confirm the superiority of the ENO schemes over the MUSCL approach in solving problems of flow fields with discontinuities which, at the same time, contain fine structure in its smooth parts.

  7. Positron emission tomography detects tissue metabolic activity in myocardial segments with persistent thallium perfusion defects

    SciTech Connect

    Brunken, R.; Schwaiger, M.; Grover-McKay, M.; Phelps, M.E.; Tillisch, J.; Schelbert, H.R.

    1987-09-01

    Positron emission tomography with /sup 13/N-ammonia and /sup 18/F-2-deoxyglucose was used to assess myocardial perfusion and glucose utilization in 51 myocardial segments with a stress thallium defect in 12 patients. Myocardial infarction was defined by a concordant reduction in segmental perfusion and glucose utilization, and myocardial ischemia was identified by preservation of glucose utilization in segments with rest hypoperfusion. Of the 51 segments studied, 36 had a fixed thallium defect, 11 had a partially reversible defect and 4 had a completely reversible defect. Only 15 (42%) of the 36 segments with a fixed defect and 4 (36%) of the 11 segments with a partially reversible defect exhibited myocardial infarction on study with positron tomography. In contrast, residual myocardial glucose utilization was identified in the majority of segments with a fixed (58%) or a partially reversible (64%) thallium defect. All of the segments with a completely reversible defect appeared normal on positron tomography. Apparent improvement in the thallium defect on delayed images did not distinguish segments with ischemia from infarction. Thus, positron emission tomography reveals evidence of persistent tissue metabolism in the majority of segments with a fixed or partially resolving stress thallium defect, implying that markers of perfusion alone may underestimate the extent of viable tissue in hypoperfused myocardial segments.

  8. Advancing standards for bioinformatics activities: persistence, reproducibility, disambiguation and Minimum Information About a Bioinformatics investigation (MIABi).

    PubMed

    Tan, Tin Wee; Tong, Joo Chuan; Khan, Asif M; de Silva, Mark; Lim, Kuan Siong; Ranganathan, Shoba

    2010-12-02

    The 2010 International Conference on Bioinformatics, InCoB2010, which is the annual conference of the Asia-Pacific Bioinformatics Network (APBioNet) has agreed to publish conference papers in compliance with the proposed Minimum Information about a Bioinformatics investigation (MIABi), proposed in June 2009. Authors of the conference supplements in BMC Bioinformatics, BMC Genomics and Immunome Research have consented to cooperate in this process, which will include the procedures described herein, where appropriate, to ensure data and software persistence and perpetuity, database and resource re-instantiability and reproducibility of results, author and contributor identity disambiguation and MIABi-compliance. Wherever possible, datasets and databases will be submitted to depositories with standardized terminologies. As standards are evolving, this process is intended as a prelude to the 100 BioDatabases (BioDB100) initiative whereby APBioNet collaborators will contribute exemplar databases to demonstrate the feasibility of standards-compliance and participate in refining the process for peer-review of such publications and validation of scientific claims and standards compliance. This testbed represents another step in advancing standards-based processes in the bioinformatics community which is essential to the growing interoperability of biological data, information, knowledge and computational resources.

  9. Persistence of immunoglobulin M or immunoglobulin G antibody responses to Borrelia burgdorferi 10-20 years after active Lyme disease.

    PubMed

    Kalish, R A; McHugh, G; Granquist, J; Shea, B; Ruthazer, R; Steere, A C

    2001-09-15

    The interpretation of serological results for patients who had Lyme disease many years ago is not well defined. We studied the serological status of 79 patients who had had Lyme disease 10-20 years ago and did not currently have signs or symptoms of active Lyme disease. Of the 40 patients who had had early Lyme disease alone, 4 (10%) currently had IgM responses to Borrelia burgdorferi, and 10 (25%) still had IgG reactivity to the spirochete, as determined by a 2-test approach (enzyme-linked immunosorbent assay and Western blot). Of the 39 patients who had had Lyme arthritis, 6 (15%) currently had IgM responses and 24 (62%) still had IgG reactivity to the spirochete. IgM or IgG antibody responses to B. burgdorferi may persist for 10-20 years, but these responses are not indicative of active infection.

  10. Increased fermentation activity and persistent methanogenesis in a model aquifer system following source removal of an ethanol blend release.

    PubMed

    Ma, Jie; Rixey, William G; Alvarez, Pedro J J

    2015-01-01

    The increased probability of groundwater contamination by ethanol-blended fuel calls for improved understanding of how remediation efforts affect the fate and transport of constituents of concern, including the generation and fate of fermentation byproducts. A pilot-scale (8 m³) model aquifer was used to investigate changes in the concentrations of ethanol and its metabolites (methane and volatile fatty acids) after removal of the contamination source. Following the shut-off of a continuous release of a dissolved ethanol blend (10% v:v ethanol, 50 mg/L benzene, and 50 mg/L toluene), fermentation activity was surprisingly stimulated and the concentrations of ethanol metabolites increased. A microcosm experiment showed that this result was due to a decrease in the dissolved ethanol concentration below its toxicity threshold (∼2000 mg/L for this system). Methane generation (>1.5 mg/L of dissolved methane) persisted for more than 100 days after the disappearance of ethanol, despite clean air-saturated water flowing continuously through the tank at a relative high seepage velocity (0.76 m/day). Quantitative real-time PCR showed that functional genes associated with methane metabolism (mcrA for methanogenesis and pmoA for methanotrophy) also persisted in the aquifer material. Persistent methanogenesis was apparently due to the anaerobic degradation of soil-bound organic carbon (e.g., biomass grown on ethanol and other substrates). Overall, this study reflects the complex plume dynamics following source removal, and suggests that monitoring for increases in the concentration of ethanol metabolites that impact groundwater quality should be considered.

  11. Increased fermentation activity and persistent methanogenesis in a model aquifer system following source removal of an ethanol blend release.

    PubMed

    Ma, Jie; Rixey, William G; Alvarez, Pedro J J

    2015-01-01

    The increased probability of groundwater contamination by ethanol-blended fuel calls for improved understanding of how remediation efforts affect the fate and transport of constituents of concern, including the generation and fate of fermentation byproducts. A pilot-scale (8 m³) model aquifer was used to investigate changes in the concentrations of ethanol and its metabolites (methane and volatile fatty acids) after removal of the contamination source. Following the shut-off of a continuous release of a dissolved ethanol blend (10% v:v ethanol, 50 mg/L benzene, and 50 mg/L toluene), fermentation activity was surprisingly stimulated and the concentrations of ethanol metabolites increased. A microcosm experiment showed that this result was due to a decrease in the dissolved ethanol concentration below its toxicity threshold (∼2000 mg/L for this system). Methane generation (>1.5 mg/L of dissolved methane) persisted for more than 100 days after the disappearance of ethanol, despite clean air-saturated water flowing continuously through the tank at a relative high seepage velocity (0.76 m/day). Quantitative real-time PCR showed that functional genes associated with methane metabolism (mcrA for methanogenesis and pmoA for methanotrophy) also persisted in the aquifer material. Persistent methanogenesis was apparently due to the anaerobic degradation of soil-bound organic carbon (e.g., biomass grown on ethanol and other substrates). Overall, this study reflects the complex plume dynamics following source removal, and suggests that monitoring for increases in the concentration of ethanol metabolites that impact groundwater quality should be considered. PMID:25462754

  12. Persistent neural activity in auditory cortex is related to auditory working memory in humans and nonhuman primates

    PubMed Central

    Huang, Ying; Matysiak, Artur; Heil, Peter; König, Reinhard; Brosch, Michael

    2016-01-01

    Working memory is the cognitive capacity of short-term storage of information for goal-directed behaviors. Where and how this capacity is implemented in the brain are unresolved questions. We show that auditory cortex stores information by persistent changes of neural activity. We separated activity related to working memory from activity related to other mental processes by having humans and monkeys perform different tasks with varying working memory demands on the same sound sequences. Working memory was reflected in the spiking activity of individual neurons in auditory cortex and in the activity of neuronal populations, that is, in local field potentials and magnetic fields. Our results provide direct support for the idea that temporary storage of information recruits the same brain areas that also process the information. Because similar activity was observed in the two species, the cellular bases of some auditory working memory processes in humans can be studied in monkeys. DOI: http://dx.doi.org/10.7554/eLife.15441.001 PMID:27438411

  13. Fusion Competent Synaptic Vesicles Persist upon Active Zone Disruption and Loss of Vesicle Docking.

    PubMed

    Wang, Shan Shan H; Held, Richard G; Wong, Man Yan; Liu, Changliang; Karakhanyan, Aziz; Kaeser, Pascal S

    2016-08-17

    In a nerve terminal, synaptic vesicle docking and release are restricted to an active zone. The active zone is a protein scaffold that is attached to the presynaptic plasma membrane and opposed to postsynaptic receptors. Here, we generated conditional knockout mice removing the active zone proteins RIM and ELKS, which additionally led to loss of Munc13, Bassoon, Piccolo, and RIM-BP, indicating disassembly of the active zone. We observed a near-complete lack of synaptic vesicle docking and a strong reduction in vesicular release probability and the speed of exocytosis, but total vesicle numbers, SNARE protein levels, and postsynaptic densities remained unaffected. Despite loss of the priming proteins Munc13 and RIM and of docked vesicles, a pool of releasable vesicles remained. Thus, the active zone is necessary for synaptic vesicle docking and to enhance release probability, but releasable vesicles can be localized distant from the presynaptic plasma membrane. PMID:27537483

  14. Fusion Competent Synaptic Vesicles Persist upon Active Zone Disruption and Loss of Vesicle Docking.

    PubMed

    Wang, Shan Shan H; Held, Richard G; Wong, Man Yan; Liu, Changliang; Karakhanyan, Aziz; Kaeser, Pascal S

    2016-08-17

    In a nerve terminal, synaptic vesicle docking and release are restricted to an active zone. The active zone is a protein scaffold that is attached to the presynaptic plasma membrane and opposed to postsynaptic receptors. Here, we generated conditional knockout mice removing the active zone proteins RIM and ELKS, which additionally led to loss of Munc13, Bassoon, Piccolo, and RIM-BP, indicating disassembly of the active zone. We observed a near-complete lack of synaptic vesicle docking and a strong reduction in vesicular release probability and the speed of exocytosis, but total vesicle numbers, SNARE protein levels, and postsynaptic densities remained unaffected. Despite loss of the priming proteins Munc13 and RIM and of docked vesicles, a pool of releasable vesicles remained. Thus, the active zone is necessary for synaptic vesicle docking and to enhance release probability, but releasable vesicles can be localized distant from the presynaptic plasma membrane.

  15. Functional coupling between sodium-activated potassium channels and voltage-dependent persistent sodium currents in cricket Kenyon cells

    PubMed Central

    Takahashi, Izumi

    2015-01-01

    In this study, we examined the functional coupling between Na+-activated potassium (KNa) channels and Na+ influx through voltage-dependent Na+ channels in Kenyon cells isolated from the mushroom body of the cricket Gryllus bimaculatus. Single-channel activity of KNa channels was recorded with the cell-attached patch configuration. The open probability (Po) of KNa channels increased with increasing Na+ concentration in a bath solution, whereas it decreased by the substitution of Na+ with an equimolar concentration of Li+. The Po of KNa channels was also found to be reduced by bath application of a high concentration of TTX (1 μM) and riluzole (100 μM), which inhibits both fast (INaf) and persistent (INaP) Na+ currents, whereas it was unaffected by a low concentration of TTX (10 nM), which selectively blocks INaf. Bath application of Cd2+ at a low concentration (50 μM), as an inhibitor of INaP, also decreased the Po of KNa channels. Conversely, bath application of the inorganic Ca2+-channel blockers Co2+ and Ni2+ at high concentrations (500 μM) had little effect on the Po of KNa channels, although Cd2+ (500 μM) reduced the Po of KNa channels. Perforated whole cell clamp analysis further indicated the presence of sustained outward currents for which amplitude was dependent on the amount of Na+ influx. Taken together, these results indicate that KNa channels could be activated by Na+ influx passing through voltage-dependent persistent Na+ channels. The functional significance of this coupling mechanism was discussed in relation to the membrane excitability of Kenyon cells and its possible role in the formation of long-term memory. PMID:26269549

  16. Persistent Associative Plasticity at an Identified Synapse Underlying Classical Conditioning Becomes Labile with Short-Term Homosynaptic Activation

    PubMed Central

    Schacher, Samuel

    2015-01-01

    Synapses express different forms of plasticity that contribute to different forms of memory, and both memory and plasticity can become labile after reactivation. We previously reported that a persistent form of nonassociative long-term facilitation (PNA-LTF) of the sensorimotor synapses in Aplysia californica, a cellular analog of long-term sensitization, became labile with short-term heterosynaptic reactivation and reversed when the reactivation was followed by incubation with the protein synthesis inhibitor rapamycin. Here we examined the reciprocal impact of different forms of short-term plasticity (reactivations) on a persistent form of associative long-term facilitation (PA-LTF), a cellular analog of classical conditioning, which was expressed at Aplysia sensorimotor synapses when a tetanic stimulation of the sensory neurons was paired with a brief application of serotonin on 2 consecutive days. The expression of short-term homosynaptic plasticity [post-tetanic potentiation or homosynaptic depression (HSD)], or short-term heterosynaptic plasticity [serotonin-induced facilitation or neuropeptide Phe-Met-Arg-Phe-NH2 (FMRFa)-induced depression], at synapses expressing PA-LTF did not affect the maintenance of PA-LTF. The kinetics of HSD was attenuated at synapses expressing PA-LTF, which required activation of protein kinase C (PKC). Both PA-LTF and the attenuated kinetics of HSD were reversed by either a transient blockade of PKC activity or a homosynaptic, but not heterosynaptic, reactivation when paired with rapamycin. These results indicate that two different forms of persistent synaptic plasticity, PA-LTF and PNA-LTF, expressed at the same synapse become labile when reactivated by different stimuli. SIGNIFICANCE STATEMENT Activity-dependent changes in neural circuits mediate long-term memories. Some forms of long-term memories become labile and can be reversed with specific types of reactivations, but the mechanism is complex. At the cellular level

  17. On the relationship between persistent delay activity, repetition enhancement and priming

    PubMed Central

    Tartaglia, Elisa M.; Mongillo, Gianluigi; Brunel, Nicolas

    2015-01-01

    Human efficiency in processing incoming stimuli (in terms of speed and/or accuracy) is typically enhanced by previous exposure to the same, or closely related stimuli—a phenomenon referred to as priming. In spite of the large body of knowledge accumulated in behavioral studies about the conditions conducive to priming, and its relationship with other forms of memory, the underlying neuronal correlates of priming are still under debate. The idea has repeatedly been advanced that a major neuronal mechanism supporting behaviorally-expressed priming is repetition suppression, a widespread reduction of spiking activity upon stimulus repetition which has been routinely exposed by single-unit recordings in non-human primates performing delayed-response, as well as passive fixation tasks. This proposal is mainly motivated by the observation that, in human fMRI studies, priming is associated to a significant reduction of the BOLD signal (widely interpreted as a proxy of the level of spiking activity) upon stimulus repetition. Here, we critically re-examine a large part of the electrophysiological literature on repetition suppression in non-human primates and find that repetition suppression is systematically accompanied by stimulus-selective delay period activity, together with repetition enhancement, an increase of spiking activity upon stimulus repetition in small neuronal populations. We argue that repetition enhancement constitutes a more viable candidate for a putative neuronal substrate of priming, and propose a minimal framework that links together, mechanistically and functionally, repetition suppression, stimulus-selective delay activity and repetition enhancement. PMID:25657630

  18. Upregulation of ERK1/2-eNOS via AT2 Receptors Decreases the Contractile Response to Angiotensin II in Resistance Mesenteric Arteries from Obese Rats

    PubMed Central

    Hagihara, Graziela N.; Lobato, Nubia S.; Filgueira, Fernando P.; Akamine, Eliana H.; Aragão, Danielle S.; Casarini, Dulce E.; Carvalho, Maria Helena C.; Fortes, Zuleica B.

    2014-01-01

    It has been clearly established that mitogen-activated protein kinases (MAPKS) are important mediators of angiotensin II (Ang II) signaling via AT1 receptors in the vasculature. However, evidence for a role of these kinases in changes of Ang II-induced vasoconstriction in obesity is still lacking. Here we sought to determine whether vascular MAPKs are differentially activated by Ang II in obese animals. The role of AT2 receptors was also evaluated. Male monosodium glutamate-induced obese (obese) and non-obese Wistar rats (control) were used. The circulating concentrations of Ang I and Ang II, determined by HPLC, were increased in obese rats. Ang II-induced isometric contraction was decreased in endothelium-intact resistance mesenteric arteries from obese compared with control rats and exhibited a retarded AT1 receptor antagonist response. Blocking of AT2 receptors and inhibition of either endothelial nitric oxide synthase (eNOS) or extracellular signal-regulated protein kinases 1 and 2 (ERK1/2) restored Ang II-induced contraction in obese rats. Western blot analysis revealed increased protein expression of AT2 receptors in arteries from obese rats. Basal and Ang II-induced ERK1/2 phosphorylation was also increased in obese rats. Blockade of either AT1 or AT2 receptors corrected the increased ERK1/2 phosphorylation in arteries from obese rats to levels observed in control preparations. Phosphorylation of eNOS was increased in obese rats. Incubation with the ERK1/2 inhibitor before Ang II stimulation did not affect eNOS phosphorylation in control rats; however, it corrected the increased phosphorylation of eNOS in obese rats. These results clearly demonstrate that enhanced AT2 receptor and ERK1/2-induced, NO-mediated vasodilation reduces Ang II-induced contraction in an endothelium-dependent manner in obese rats. PMID:25170617

  19. Targeting the Warburg effect in cancer cells through ENO1 knockdown rescues oxidative phosphorylation and induces growth arrest

    PubMed Central

    Riganti, Chiara; Chattaragada, Michelle Samuel; Principe, Moitza; Roux, Cecilia; Zhou, Weidong; Petricoin, Emanuel F.; Cappello, Paola; Novelli, Francesco

    2016-01-01

    In the last 5 years, novel knowledge on tumor metabolism has been revealed with the identification of critical factors that fuel tumors. Alpha-enolase (ENO1) is commonly over-expressed in tumors and is a clinically relevant candidate molecular target for immunotherapy. Here, we silenced ENO1 in human cancer cell lines and evaluated its impact through proteomic, biochemical and functional approaches. ENO1 silencing increased reactive oxygen species that were mainly generated through the sorbitol and NADPH oxidase pathways, as well as autophagy and catabolic pathway adaptations, which together affect cancer cell growth and induce senescence. These findings represent the first comprehensive metabolic analysis following ENO1 silencing. Inhibition of ENO1, either alone, or in combination with other pathways which were perturbed by ENO1 silencing, opens novel avenues for future therapeutic approaches. PMID:26734996

  20. Hippocampal noradrenergic activation is necessary for object recognition memory consolidation and can promote BDNF increase and memory persistence.

    PubMed

    Mello-Carpes, Pâmela B; da Silva de Vargas, Liane; Gayer, Mateus Cristofari; Roehrs, Rafael; Izquierdo, Ivan

    2016-01-01

    Previously we showed that activation of the Nucleus of the Solitary Tract (NTS)-Nucleus Paragigantocellularis (PGi)-Locus coeruleus (LC) pathway, which theoretically culminates with norepinephrine (NE) release in dorsal hippocampus (CA1 region) and basolateral amygdala (BLA) is necessary for the consolidation of object recognition (OR) memory. Here we show that, while the microinjection of the beta-noradrenergic receptor blocker timolol into CA1 impairs OR memory consolidation, the microinjection of norepinephrine (NE) promotes the persistence of this type of memory. Further, we show that OR consolidation is attended by an increase of norepinephrine (NE) levels and of the expression of brain derived neurotrophic factor (BDNF) in hippocampus, which are impaired by inactivation of the NTS-PGi-LC pathway by the infusion of muscimol into the NTS. PMID:26691781

  1. Hippocampal noradrenergic activation is necessary for object recognition memory consolidation and can promote BDNF increase and memory persistence.

    PubMed

    Mello-Carpes, Pâmela B; da Silva de Vargas, Liane; Gayer, Mateus Cristofari; Roehrs, Rafael; Izquierdo, Ivan

    2016-01-01

    Previously we showed that activation of the Nucleus of the Solitary Tract (NTS)-Nucleus Paragigantocellularis (PGi)-Locus coeruleus (LC) pathway, which theoretically culminates with norepinephrine (NE) release in dorsal hippocampus (CA1 region) and basolateral amygdala (BLA) is necessary for the consolidation of object recognition (OR) memory. Here we show that, while the microinjection of the beta-noradrenergic receptor blocker timolol into CA1 impairs OR memory consolidation, the microinjection of norepinephrine (NE) promotes the persistence of this type of memory. Further, we show that OR consolidation is attended by an increase of norepinephrine (NE) levels and of the expression of brain derived neurotrophic factor (BDNF) in hippocampus, which are impaired by inactivation of the NTS-PGi-LC pathway by the infusion of muscimol into the NTS.

  2. New evidence for persistent impact-generated hydrothermal activity in the Miocene Ries impact structure, Germany

    NASA Astrophysics Data System (ADS)

    Arp, Gernot; Kolepka, Claudia; Simon, Klaus; Karius, Volker; Nolte, Nicole; Hansen, Bent T.

    2013-12-01

    The extent of impact-generated hydrothermal activity in the 24 km sized Ries impact structure has been controversially discussed. To date, mineralogical and isotopic investigations point to a restriction of hydrothermal activity to the impact-melt bearing breccias, specifically the crater-fill suevite. Here, we present new petrographic, geochemical, and isotopic data of postimpact carbonate deposits, which indicate a hydrothermal activity more extended than previously assumed. Specifically, carbonates of the Erbisberg, a spring mound located upon the inner crystalline ring of the crater, show travertine facies types not seen in any of the previously investigated sublacustrine soda lake spring mounds of the Ries basin. In particular, the streamer carbonates, which result from the encrustation of microbial filaments in subaerial spring effluents between 60 and 70 °C, are characteristic of a hydrothermal origin. While much of the primary geochemical and isotopic signatures in the mound carbonates have been obliterated by diagenesis, a postimpact calcite vein from brecciated gneiss of the subsurface crater floor revealed a flat rare earth element pattern with a clear positive Eu anomaly, indicating a hydrothermal fluid convection in the crater basement. Finally, the strontium isotope stratigraphic correlation of the travertine mound with the crater basin succession suggests a hydrothermal activity for about 250,000 yr after the impact, which would be much longer than previously assumed.

  3. Persistence of Anticancer Activity in Berry Extracts after Simulated Gastrointestinal Digestion and Colonic Fermentation

    PubMed Central

    Brown, Emma M.; McDougall, Gordon J.; Stewart, Derek; Pereira-Caro, Gema; González-Barrio, Rocio; Allsopp, Philip; Magee, Pamela; Crozier, Alan; Rowland, Ian; Gill, Chris I. R.

    2012-01-01

    Fruit and vegetable consumption is associated at the population level with a protective effect against colorectal cancer. Phenolic compounds, especially abundant in berries, are of interest due to their putative anticancer activity. After consumption, however, phenolic compounds are subject to digestive conditions within the gastrointestinal tract that alter their structures and potentially their function. However, the majority of phenolic compounds are not efficiently absorbed in the small intestine and a substantial portion pass into the colon. We characterized berry extracts (raspberries, strawberries, blackcurrants) produced by in vitro-simulated upper intestinal tract digestion and subsequent fecal fermentation. These extracts and selected individual colonic metabolites were then evaluated for their putative anticancer activities using in vitro models of colorectal cancer, representing the key stages of initiation, promotion and invasion. Over a physiologically-relevant dose range (0–50 µg/ml gallic acid equivalents), the digested and fermented extracts demonstrated significant anti-genotoxic, anti-mutagenic and anti-invasive activity on colonocytes. This work indicates that phenolic compounds from berries undergo considerable structural modifications during their passage through the gastrointestinal tract but their breakdown products and metabolites retain biological activity and can modulate cellular processes associated with colon cancer. PMID:23185422

  4. Persistence of anticancer activity in berry extracts after simulated gastrointestinal digestion and colonic fermentation.

    PubMed

    Brown, Emma M; McDougall, Gordon J; Stewart, Derek; Pereira-Caro, Gema; González-Barrio, Rocio; Allsopp, Philip; Magee, Pamela; Crozier, Alan; Rowland, Ian; Gill, Chris I R

    2012-01-01

    Fruit and vegetable consumption is associated at the population level with a protective effect against colorectal cancer. Phenolic compounds, especially abundant in berries, are of interest due to their putative anticancer activity. After consumption, however, phenolic compounds are subject to digestive conditions within the gastrointestinal tract that alter their structures and potentially their function. However, the majority of phenolic compounds are not efficiently absorbed in the small intestine and a substantial portion pass into the colon. We characterized berry extracts (raspberries, strawberries, blackcurrants) produced by in vitro-simulated upper intestinal tract digestion and subsequent fecal fermentation. These extracts and selected individual colonic metabolites were then evaluated for their putative anticancer activities using in vitro models of colorectal cancer, representing the key stages of initiation, promotion and invasion. Over a physiologically-relevant dose range (0-50 µg/ml gallic acid equivalents), the digested and fermented extracts demonstrated significant anti-genotoxic, anti-mutagenic and anti-invasive activity on colonocytes. This work indicates that phenolic compounds from berries undergo considerable structural modifications during their passage through the gastrointestinal tract but their breakdown products and metabolites retain biological activity and can modulate cellular processes associated with colon cancer.

  5. Persistent Prelimbic Cortex Activity Contributes to Enhanced Learned Fear Expression in Females

    ERIC Educational Resources Information Center

    Fenton, Georgina E.; Pollard, Amelia K.; Halliday, David M.; Mason, Rob; Bredy, Timothy W.; Stevenson, Carl W.

    2014-01-01

    Anxiety disorders, such as post-traumatic stress, are more prevalent in women and are characterized by impaired inhibition of learned fear and medial prefrontal cortex (mPFC) dysfunction. Here we examined sex differences in fear extinction and mPFC activity in rats. Females showed more learned fear expression during extinction and its recall, but…

  6. Persistent Organic Pollutants Modify Gut Microbiota–Host Metabolic Homeostasis in Mice Through Aryl Hydrocarbon Receptor Activation

    PubMed Central

    Zhang, Limin; Nichols, Robert G.; Correll, Jared; Murray, Iain A.; Tanaka, Naoki; Smith, Philip B.; Hubbard, Troy D.; Sebastian, Aswathy; Albert, Istvan; Hatzakis, Emmanuel; Gonzalez, Frank J.; Perdew, Gary H.

    2015-01-01

    Background Alteration of the gut microbiota through diet and environmental contaminants may disturb physiological homeostasis, leading to various diseases including obesity and type 2 diabetes. Because most exposure to environmentally persistent organic pollutants (POPs) occurs through the diet, the host gastrointestinal tract and commensal gut microbiota are likely to be exposed to POPs. Objectives We examined the effect of 2,3,7,8-tetrachlorodibenzofuran (TCDF), a persistent environmental contaminant, on gut microbiota and host metabolism, and we examined correlations between gut microbiota composition and signaling pathways. Methods Six-week-old male wild-type and Ahr–/– mice on the C57BL/6J background were treated with 24 μg/kg TCDF in the diet for 5 days. We used 16S rRNA gene sequencing, 1H nuclear magnetic resonance (NMR) metabolomics, targeted ultra-performance liquid chromatography coupled with triplequadrupole mass spectrometry, and biochemical assays to determine the microbiota compositions and the physiological and metabolic effects of TCDF. Results Dietary TCDF altered the gut microbiota by shifting the ratio of Firmicutes to Bacteroidetes. TCDF-treated mouse cecal contents were enriched with Butyrivibrio spp. but depleted in Oscillobacter spp. compared with vehicle-treated mice. These changes in the gut microbiota were associated with altered bile acid metabolism. Further, dietary TCDF inhibited the farnesoid X receptor (FXR) signaling pathway, triggered significant inflammation and host metabolic disorders as a result of activation of bacterial fermentation, and altered hepatic lipogenesis, gluconeogenesis, and glycogenolysis in an AHR-dependent manner. Conclusion These findings provide new insights into the biochemical consequences of TCDF exposure involving the alteration of the gut microbiota, modulation of nuclear receptor signaling, and disruption of host metabolism. Citation Zhang L, Nichols RG, Correll J, Murray IA, Tanaka N, Smith PB

  7. Editor's Highlight: Neonatal Activation of the Xenobiotic-Sensors PXR and CAR Results in Acute and Persistent Down-regulation of PPARα-Signaling in Mouse Liver.

    PubMed

    Li, Cindy Yanfei; Cheng, Sunny Lihua; Bammler, Theo K; Cui, Julia Yue

    2016-10-01

    Safety concerns have emerged regarding the potential long-lasting effects due to developmental exposure to xenobiotics. The pregnane X receptor (PXR) and constitutive androstane receptor (CAR) are critical xenobiotic-sensing nuclear receptors that are highly expressed in liver. The goal of this study was to test our hypothesis that neonatal exposure to PXR- or CAR-activators not only acutely but also persistently regulates the expression of drug-processing genes (DPGs). A single dose of the PXR-ligand PCN (75 mg/kg), CAR-ligand TCPOBOP (3 mg/kg), or vehicle (corn oil) was administered intraperitoneally to 3-day-old neonatal wild-type mice. Livers were collected 24 h post-dose or from adult mice at 60 days of age, and global gene expression of these mice was determined using Affymetrix Mouse Transcriptome Assay 1.0. In neonatal liver, PCN up-regulated 464 and down-regulated 449 genes, whereas TCPOBOP up-regulated 308 and down-regulated 112 genes. In adult liver, there were 15 persistently up-regulated and 22 persistently down-regulated genes following neonatal exposure to PCN, as well as 130 persistently up-regulated and 18 persistently down-regulated genes following neonatal exposure to TCPOBOP. Neonatal exposure to both PCN and TCPOBOP persistently down-regulated multiple Cyp4a members, which are prototypical-target genes of the lipid-sensor PPARα, and this correlated with decreased PPARα-binding to the Cyp4a gene loci. RT-qPCR, western blotting, and enzyme activity assays in livers of wild-type, PXR-null, and CAR-null mice confirmed that the persistent down-regulation of Cyp4a was PXR and CAR dependent. In conclusion, neonatal exposure to PXR- and CAR-activators both acutely and persistently regulates critical genes involved in xenobiotic and lipid metabolism in liver. PMID:27413110

  8. Editor's Highlight: Neonatal Activation of the Xenobiotic-Sensors PXR and CAR Results in Acute and Persistent Down-regulation of PPARα-Signaling in Mouse Liver.

    PubMed

    Li, Cindy Yanfei; Cheng, Sunny Lihua; Bammler, Theo K; Cui, Julia Yue

    2016-10-01

    Safety concerns have emerged regarding the potential long-lasting effects due to developmental exposure to xenobiotics. The pregnane X receptor (PXR) and constitutive androstane receptor (CAR) are critical xenobiotic-sensing nuclear receptors that are highly expressed in liver. The goal of this study was to test our hypothesis that neonatal exposure to PXR- or CAR-activators not only acutely but also persistently regulates the expression of drug-processing genes (DPGs). A single dose of the PXR-ligand PCN (75 mg/kg), CAR-ligand TCPOBOP (3 mg/kg), or vehicle (corn oil) was administered intraperitoneally to 3-day-old neonatal wild-type mice. Livers were collected 24 h post-dose or from adult mice at 60 days of age, and global gene expression of these mice was determined using Affymetrix Mouse Transcriptome Assay 1.0. In neonatal liver, PCN up-regulated 464 and down-regulated 449 genes, whereas TCPOBOP up-regulated 308 and down-regulated 112 genes. In adult liver, there were 15 persistently up-regulated and 22 persistently down-regulated genes following neonatal exposure to PCN, as well as 130 persistently up-regulated and 18 persistently down-regulated genes following neonatal exposure to TCPOBOP. Neonatal exposure to both PCN and TCPOBOP persistently down-regulated multiple Cyp4a members, which are prototypical-target genes of the lipid-sensor PPARα, and this correlated with decreased PPARα-binding to the Cyp4a gene loci. RT-qPCR, western blotting, and enzyme activity assays in livers of wild-type, PXR-null, and CAR-null mice confirmed that the persistent down-regulation of Cyp4a was PXR and CAR dependent. In conclusion, neonatal exposure to PXR- and CAR-activators both acutely and persistently regulates critical genes involved in xenobiotic and lipid metabolism in liver.

  9. Persistent differences in patterns of brain activation after sports-related concussion: a longitudinal functional magnetic resonance imaging study.

    PubMed

    Dettwiler, Annegret; Murugavel, Murali; Putukian, Margot; Cubon, Valerie; Furtado, John; Osherson, Daniel

    2014-01-15

    Avoiding recurrent injury in sports-related concussion (SRC) requires understanding the neural mechanisms involved during the time of recovery after injury. The decision for return-to-play is one of the most difficult responsibilities facing the physician, and so far this decision has been based primarily on neurological examination, symptom checklists, and neuropsychological (NP) testing. Functional magnetic resonance imaging (fMRI) may be an additional, more objective tool to assess the severity and recovery of function after concussion. The purpose of this study was to define neural correlates of SRC during the 2 months after injury in varsity contact sport athletes who suffered a SRC. All athletes were scanned as they performed an n-back task, for n=1, 2, 3. Subjects were scanned within 72 hours (session one), at 2 weeks (session two), and 2 months (session three) post-injury. Compared with age and sex matched normal controls, concussed subjects demonstrated persistent, significantly increased activation for the 2 minus 1 n-back contrast in bilateral dorsolateral prefrontal cortex (DLPFC) in all three sessions and in the inferior parietal lobe in session one and two (α≤0.01 corrected). Measures of task performance revealed no significant differences between concussed versus control groups at any of the three time points with respect to any of the three n-back tasks. These findings suggest that functional brain activation differences persist at 2 months after injury in concussed athletes, despite the fact that their performance on a standard working memory task is comparable to normal controls and normalization of clinical and NP test results. These results might indicate a delay between neural and behaviorally assessed recovery after SRC. PMID:23914845

  10. ENO1 promotes tumor proliferation and cell adhesion mediated drug resistance (CAM-DR) in Non-Hodgkin's Lymphomas

    SciTech Connect

    Zhu, Xinghua; Miao, Xiaobing; Wu, Yaxun; Li, Chunsun; Guo, Yan; Liu, Yushan; Chen, Yali; Lu, Xiaoyun; Wang, Yuchan; He, Song

    2015-07-15

    Enolases are glycolytic enzymes responsible for the ATP-generated conversion of 2-phosphoglycerate to phosphoenolpyruvate. In addition to the glycolytic function, Enolase 1 (ENO1) has been reported up-regulation in several tumor tissues. In this study, we investigated the expression and biologic function of ENO1 in Non-Hodgkin's Lymphomas (NHLs). Clinically, by western blot analysis we observed that ENO1 expression was apparently higher in diffuse large B-cell lymphoma than in the reactive lymphoid tissues. Subsequently, immunohistochemical staining of 144 NHLs suggested that the expression of ENO1 was significantly lower in the indolent lymphomas compared with the progressive lymphomas. Further, we identified ENO1 as an independent prognostic factor, and it was significantly correlated with overall survival of NHL patients. In addition, we found that ENO1 could promote cell proliferation, regulate cell cycle associated gene and PI3K/AKT signaling pathway in NHLs. Finally, we verified that ENO1 participated in the process of lymphoma cell adhesion mediated drug resistance (CAM-DR). Adhesion to FN or HS5 cells significantly protected OCI-Ly8 and Daudi cells from cytotoxicity compared with those cultured in suspension, and these effects were attenuated when transfected with ENO1-siRNA. Based on the study, we propose that inhibition of ENO1 expression may be a novel strategy for therapy for NHLs patients, and it may be a target for drug resistance. - Highlights: • ENO1 expression is reversely correlated with clinical outcomes of patients with NHLs. • ENO1 promotes the proliferation of NHL cells. • ENO1 regulates cell adhesion mediated drug resistance.

  11. Priming the Holiday Spirit: Persistent Activation due to Extra-Experimental Experiences

    PubMed Central

    Coane, Jennifer H.; Balota, David A.

    2010-01-01

    The concept of activation is a critical component of many models of cognition. A key characteristic of activation is that recent experience with a concept or stimulus increases the accessibility of the corresponding representation. The extent to which increases in accessibility occur as a result of experiences outside of laboratory settings has not been extensively explored. In the present study, we presented lexical stimuli associated to different holidays and festivities over the course of a year in a lexical decision task. When stimulus meaning and time of testing were congruent (e.g., leprechaun in March), response times were faster and accuracy greater than when meaning and time of test were incongruent (e.g., leprechaun in November). Congruency also benefited performance on a surprise free recall task of the items presented earlier in the lexical decision task. Discussion focuses on potential theoretical accounts of this heightened accessibility of time-of-the-year relevant concepts. PMID:19966266

  12. Influence of coronary artery diameter on eNOS protein content

    NASA Technical Reports Server (NTRS)

    Laughlin, M. H.; Turk, J. R.; Schrage, W. G.; Woodman, C. R.; Price, E. M.

    2003-01-01

    The purpose of this study was to test the hypothesis that the content of endothelial nitric oxide synthase (eNOS) protein (eNOS protein/g total artery protein) increases with decreasing artery diameter in the coronary arterial tree. Content of eNOS protein was determined in porcine coronary arteries with immunoblot analysis. Arteries were isolated in six size categories from each heart: large arteries [301- to 2,500-microm internal diameter (ID)], small arteries (201- to 300-microm ID), resistance arteries (151- to 200-microm ID), large arterioles (101- to 150-microm ID), intermediate arterioles (51- to 100-microm ID), and small arterioles(<50-microm ID). To obtain sufficient protein for analysis from small- and intermediate-sized arterioles, five to seven arterioles 1-2 mm in length were pooled into one sample for each animal. Results establish that the number of smooth muscle cells per endothelial cell decreases from a number of 10 to 15 in large coronary arteries to 1 in the smallest arterioles. Immunohistochemistry revealed that eNOS is located only in endothelial cells in all sizes of coronary artery and in coronary capillaries. Contrary to our hypothesis, eNOS protein content did not increase with decreasing size of coronary artery. Indeed, the smallest coronary arterioles had less eNOS protein per gram of total protein than the large coronary arteries. These results indicate that eNOS protein content is greater in the endothelial cells of conduit arteries, resistance arteries, and large arterioles than in small coronary arterioles.

  13. Hindlimb unweighting decreases endothelium-dependent dilation and eNOS expression in soleus not gastrocnemius

    NASA Technical Reports Server (NTRS)

    Woodman, C. R.; Schrage, W. G.; Rush, J. W.; Ray, C. A.; Price, E. M.; Hasser, E. M.; Laughlin, M. H.

    2001-01-01

    We tested the hypothesis that hindlimb unweighting (HLU) decreases endothelium-dependent vasodilation and expression of endothelial nitric oxide synthase (eNOS) and superoxide dismutase-1 (SOD-1) in arteries of skeletal muscle with reduced blood flow during HLU. Sprague-Dawley rats (300-350 g) were exposed to HLU (n = 15) or control (n = 15) conditions for 14 days. ACh-induced dilation was assessed in muscle with reduced [soleus (Sol)] or unchanged [gastrocnemius (Gast)] blood flow during HLU. eNOS and SOD-1 expression were measured in feed arteries (FA) and in first-order (1A), second-order (2A), and third-order (3A) arterioles. Dilation to infusion of ACh in vivo was blunted in Sol but not Gast. In arteries of Sol muscle, HLU decreased eNOS mRNA and protein content. eNOS mRNA content was significantly less in Sol FA (35%), 1A arterioles (25%) and 2A arterioles (18%). eNOS protein content was less in Sol FA (64%) and 1A arterioles (65%) from HLU rats. In arteries of Gast, HLU did not decrease eNOS mRNA or protein. SOD-1 mRNA expression was less in Sol 2A arterioles (31%) and 3A arterioles (29%) of HLU rats. SOD-1 protein content was less in Sol FA (67%) but not arterioles. SOD-1 mRNA and protein content were not decreased in arteries from Gast. These data indicate that HLU decreases endothelium-dependent vasodilation, eNOS expression, and SOD-1 expression primarily in arteries of Sol muscle where blood flow is reduced during HLU.

  14. Inappropriate Neural Activity during a Sensitive Period in Embryogenesis Results in Persistent Seizure-like Behavior

    PubMed Central

    Giachello, Carlo N.G.; Baines, Richard A.

    2015-01-01

    Summary Maturation of neural circuits requires activity-dependent processes that underpin the emergence of appropriate behavior in the adult. It has been proposed that disruption of these events, during specific critical periods when they exert maximal influence, may lead to neurodevelopmental diseases, including epilepsy [1, 2, 3]. However, complexity of neurocircuitry, coupled with the lack of information on network formation in mammals, makes it difficult to directly investigate this hypothesis. Alternative models, including the fruit fly Drosophila melanogaster, show remarkable similarities between experimental seizure-like activity and clinical phenotypes [4, 5, 6]. In particular, a group of flies, termed bang-sensitive (bs) mutants have been extensively used to investigate the pathophysiological mechanisms underlying seizure [7, 8, 9, 10, 11, 12]. Seizure phenotype can be measured in larval stages using an electroshock assay, and this behavior in bs mutants is dramatically reduced following ingestion of typical anti-epileptic drugs (AEDs; [13]). In this study we describe a critical period of embryonic development in Drosophila during which manipulation of neural activity is sufficient to significantly influence seizure behavior at postembryonic stages. We show that inhibition of elevated activity, characteristic of bs seizure models, during the critical period is sufficient to suppress seizure. By contrast, increasing neuronal excitation during the same period in wild-type (WT) is sufficient to permanently induce a seizure behavior. Further, we show that induction of seizure in WT correlates with functional alteration of motoneuron inputs that is a characteristic of bs mutants. Induction of seizure is rescued by prior administration of AEDs, opening a new perspective for early drug intervention in the treatment of genetic epilepsy. PMID:26549258

  15. Evidence for the persistence of an active endogenous retrovirus (ERVE) in humans.

    PubMed

    Naveira, Horacio; Bello, Xabier; Abal-Fabeiro, José Luis; Maside, Xulio

    2014-10-01

    Transposable elements (TEs) account for nearly half (44 %) of the human genome. However, their overall activity has been steadily declining over the past 35-50 million years, so that <0.05 % of TEs are presumably still "alive" (potentially transposable) in human populations. All the active elements are retrotransposons, either autonomous (LINE-1 and possibly the endogenous retrovirus ERVK), or non-autonomous (Alu and SVA, whose transposition is dependent on the LINE-1 enzymatic machinery). Here we show that a lineage of the endogenous retrovirus ERVE was recently engaged in ectopic recombination events and may have at least one potentially fully functional representative, initially reported as a novel retrovirus isolated from blood cells of a Chinese patient with chronic myeloid leukemia, which bears signals of positive selection on its envelope region. Altogether, there is strong evidence that ERVE should be included in the short list of potentially active TEs, and we give clues on how to identify human specific insertions of this element that are likely to be segregating in some of our populations.

  16. Persistence in recurrent geomagnetic activity and its connection with Space Climate

    NASA Astrophysics Data System (ADS)

    Diego, P.; Storini, M.; Laurenza, M.

    2010-06-01

    Recurrent geomagnetic activity is mainly linked to the passage of interplanetary corotating solar wind structures in the near-Earth space. We studied geomagnetic recurrences for which an enhanced value of the autocorrelation coefficient exists between the data of two adjacent Bartels rotations in aa, Kp, Dst, AE time series, for the period 1954-2007, covering about 5 solar cycles (from cycle 19 to cycle 23). A new index (P), based on autocorrelation analysis, has been introduced to estimate also the duration up to seven Bartels rotations of each solar structure (or group of structures) producing geomagnetic recurrences with high autocorrelation (correlation coefficient ≥ 0.3). We could infer whether recurrent geomagnetic activity is due to successive short-lived (at least 2 Bartels rotations) or to long-lasting corotating structures (up to 7 or more Bartels rotations). Generally, time periods characterized by recurrent geomagnetic activity are longer during the descending phase of even-numbered cycles (20, 22). Nevertheless, we found that recurrences determined by long-lived interplanetary structures are detected mainly in the descending phase of cycles 19 and 23. Finally, we point out that the average levels of the computed indices during the descending phase of each solar cycle show a significant anticorrelation with the sunspot area integrated over the subsequent cycle, giving new insights for Space Climate forecast.

  17. Non-viral eNOS gene delivery and transfection with stents for the treatment of restenosis

    PubMed Central

    2010-01-01

    Background In this study, we have examined local non-viral gene delivery, transfection, and therapeutic efficacy of endothelial nitric oxide synthase (eNOS) encoding plasmid DNA administered using coated stents in a rabbit iliac artery restenosis model. Methods Lipopolyplexes (LPPs) with eNOS expressing plasmid DNA were immobilized on stainless steel stents using poly(D,L-lactide-co-glycolide) (PLGA) and type B gelatin coatings. The gene-eluting stents were implanted bilaterally in the denuded iliac arteries and eNOS transfection and therapeutic efficacy were examined 14 days after implantation. Results The results show that non-viral lipopolyplex-coated stents can efficiently tranfect eNOS locally in the arterial lumen assessed by PCR and ELISA. Human eNOS ELISA levels were significantly raised 24 hours after transfection compared to controls (125 pg eNOS compared to <50 pg for all controls including naked DNA). Local eNOS production suppressed smooth muscle cell proliferation and promoted re-endothelialization of the artery showing a significant reduction in restenosis of 1.75 neointima/media ratio for stents with lipoplexes encoding eNOS compared with 2.3 neointima/media ratio for stents with lipoplexes encosing an empty vector. Conclusions These results support the hypothesis that a potent non-viral gene vector encoding for eNOS coated onto a stent can inhibit restenosis through inhibition of smooth muscle cell growth and promotion of a healthy endothelium. PMID:20875110

  18. Persistent Activation of the Innate Immune Response in Adult Drosophila Following Radiation Exposure During Larval Development.

    PubMed

    Sudmeier, Lisa J; Samudrala, Sai-Suma; Howard, Steven P; Ganetzky, Barry

    2015-11-01

    Cranial radiation therapy (CRT) is an effective treatment for pediatric central nervous system malignancies, but survivors often suffer from neurological and neurocognitive side effects that occur many years after radiation exposure. Although the biological mechanisms underlying these deleterious side effects are incompletely understood, radiation exposure triggers an acute inflammatory response that may evolve into chronic inflammation, offering one avenue of investigation. Recently, we developed a Drosophila model of the neurotoxic side effects of radiation exposure. Here we use this model to investigate the role of the innate immune system in response to radiation exposure. We show that the innate immune response and NF-ĸB target gene expression is activated in the adult Drosophila brain following radiation exposure during larval development, and that this response is sustained in adult flies weeks after radiation exposure. We also present preliminary data suggesting that innate immunity is radioprotective during Drosophila development. Together our data suggest that activation of the innate immune response may be beneficial initially for survival following radiation exposure but result in long-term deleterious consequences, with chronic inflammation leading to impaired neuronal function and viability at later stages. This work lays the foundation for future studies of how the innate immune response is triggered by radiation exposure and its role in mediating the biological responses to radiation. These studies may facilitate the development of strategies to reduce the deleterious side effects of CRT.

  19. Persistence of diet-induced obesity despite access to voluntary activity in mice lacking sarcolipin

    PubMed Central

    Gamu, Daniel; Trinh, Anton; Bombardier, Eric; Tupling, A Russell

    2015-01-01

    Several rodent models of obesity have been shown to develop excessive adiposity only when voluntary cage ambulation is restricted. We have previously shown that mice lacking the sarco(endo)plasmic reticulum Ca2+-ATPase pump regulatory protein sarcolipin (Sln–/–), an uncoupler of Ca2+ uptake, develop excessive diet-induced obesity under standard housing conditions. However, it is unclear whether this phenotype is due, in part, to the sedentary housing environment in which these animals are kept. To address this, we allowed wild-type and Sln–/– animals ad libitum access to voluntary wheel running while consuming a standard chow or high-fat diet for 8 weeks. During this period, wheel revolutions were monitored along with weekly mass gain. Postdiet glucose tolerance and visceral adiposity were also taken. The volume of wheel running completed was similar between genotype, regardless of diet. Although voluntary activity reduced mass gain relative to sedentary controls within each diet (P < 0.05), visceral adiposity was surprisingly unaltered with activity. However, Sln–/– mice developed excessive obesity (P < 0.05) and glucose intolerance (P < 0.05) with high-fat feeding relative to wild-type controls. These findings indicate that the excessive diet-induced obese phenotype previously observed in Sln–/– mice is not the result of severely restricted daily ambulation, but in fact the inability to recruit uncoupling of the Ca2+-ATPase pump. PMID:26400985

  20. SO2 Emissions at Semeru Volcano, Indonesia: Characterization and Quantification of Persistent and Periodic Explosive Activity.

    NASA Astrophysics Data System (ADS)

    Smekens, J. F.; Clarke, A. B.; Burton, M. R.; Harijoko, A.; Wibowo, H.

    2014-12-01

    We present the first measurements of SO2 emissions at Semeru volcano, Indonesia, using an SO2 camera. Activity at Semeru is characterized by quiescent degassing interspersed with short-lived explosive events with low ash burden. The interval between explosions was measured at 32.1±15.7 minutes in a webcam survey of the volcano between the months of June and December 2013. We distinguish between two types of events: shorter events (type I: ~5 mins duration) with emissions returning quickly to baseline levels, and longer events (type II: ~15 mins duration) often showing multiple pulses and a longer period of increased emissions before a return to quiescent levels. Type I events represent >90% of the activity and release an average of 200-450 kg of SO2 per event. The single type II event we documented with the SO2 camera released a total of 1300 kg of SO2. We estimate the daily average emissions of Semeru to be 21-60 t d-1 of SO2, amounting to a yearly output of 7.5-22 Gg (7,500 - 22,000 metric tons), with 35-60% released during explosive events. The time series patterns of degassing are consistent with the existence of a viscous plug at the top of the conduit, causing accumulation and pressurization of the magma to produce the explosive events.

  1. SO2 emissions at Semeru volcano, Indonesia: Characterization and quantification of persistent and periodic explosive activity

    NASA Astrophysics Data System (ADS)

    Smekens, Jean-François; Clarke, Amanda B.; Burton, Michael R.; Harijoko, Agung; Wibowo, Haryo E.

    2015-07-01

    We present the first measurements of SO2 emissions at Semeru volcano, Indonesia, using an SO2 camera. Activity at Semeru is characterized by quiescent degassing interspersed with short-lived explosive events with low ash burden. The interval between explosions was measured at 32.1 ± 15.7 min in a webcam survey of the volcano between the months of June and December 2013. We distinguish between two types of events: shorter events (type I: ~ 5 min duration) with emissions returning quickly to baseline levels, and longer events (type II: ~ 15 min duration) often showing multiple pulses and a longer period of increased emissions before a return to quiescent levels. Type I events represent > 90% of the activity and release an average of 200-500 kg of SO2 per event. The single type II event we documented with the SO2 camera released a total of 1460 kg of SO2. We estimate the daily average emissions of Semeru to be 21-71 t d- 1 of SO2, amounting to a yearly output of 8-26 Gg (8000-26,000 metric tons), with 35-65% released during explosive events. The time series patterns of degassing are consistent with the existence of a viscous plug at the top of the conduit, which seals the conduit immediately prior to explosive events, causing pressurization of the underlying magma followed by a sudden release of gas and fragmented magma.

  2. Persistent Activation of the Innate Immune Response in Adult Drosophila Following Radiation Exposure During Larval Development

    PubMed Central

    Sudmeier, Lisa J.; Samudrala, Sai-Suma; Howard, Steven P.; Ganetzky, Barry

    2015-01-01

    Cranial radiation therapy (CRT) is an effective treatment for pediatric central nervous system malignancies, but survivors often suffer from neurological and neurocognitive side effects that occur many years after radiation exposure. Although the biological mechanisms underlying these deleterious side effects are incompletely understood, radiation exposure triggers an acute inflammatory response that may evolve into chronic inflammation, offering one avenue of investigation. Recently, we developed a Drosophila model of the neurotoxic side effects of radiation exposure. Here we use this model to investigate the role of the innate immune system in response to radiation exposure. We show that the innate immune response and NF-ĸB target gene expression is activated in the adult Drosophila brain following radiation exposure during larval development, and that this response is sustained in adult flies weeks after radiation exposure. We also present preliminary data suggesting that innate immunity is radioprotective during Drosophila development. Together our data suggest that activation of the innate immune response may be beneficial initially for survival following radiation exposure but result in long-term deleterious consequences, with chronic inflammation leading to impaired neuronal function and viability at later stages. This work lays the foundation for future studies of how the innate immune response is triggered by radiation exposure and its role in mediating the biological responses to radiation. These studies may facilitate the development of strategies to reduce the deleterious side effects of CRT. PMID:26333838

  3. Regime shift in Arabian dust activity, triggered by persistent Fertile Crescent drought

    NASA Astrophysics Data System (ADS)

    Notaro, Michael; Yu, Yan; Kalashnikova, Olga V.

    2015-10-01

    The Arabian Peninsula has experienced pronounced interannual to decadal variability in dust activity, including an abrupt regime shift around 2006 from an inactive dust period during 1998-2005 to an active period during 2007-2013. Corresponding in time to the onset of this regime shift, the climate state transitioned into a combined La Niña and negative phase of the Pacific Decadal Oscillation, which incited a hiatus in global warming in the 2000s. Superimposed upon a long-term regional drying trend, synergistic interactions between these teleconnection modes triggered the establishment of a devastating and prolonged drought, which engulfed the Fertile Crescent, namely, Iraq and Syria, and led to crop failure and civil unrest. Dried soils and diminished vegetation cover in the Fertile Crescent, as evident through remotely sensed enhanced vegetation indices, supported greater dust generation and transport to the Arabian Peninsula in 2007-2013, as identified both in increased dust days observed at weather stations and enhanced remotely sensed aerosol optical depth. According to backward trajectory analysis of dust days on the Arabian Peninsula, increased dust lifting and atmospheric dust concentration in the Fertile Crescent during this recent, prolonged drought episode supported a greater frequency of dust events across the peninsula with associated northerly trajectories and led to the dust regime shift. These findings are particularly concerning, considering projections of warming and drying for the eastern Mediterranean region and potential collapse of the Fertile Crescent during this century.

  4. Cardioprotective effects of luteolin on ischemia/reperfusion injury in diabetic rats are modulated by eNOS and the mitochondrial permeability transition pathway.

    PubMed

    Yang, Jin-Ting; Qian, Ling-Bo; Zhang, Feng-Jiang; Wang, Jue; Ai, Heng; Tang, Li-Hui; Wang, Hui-Ping

    2015-04-01

    Myocardial ischemia/reperfusion (I/R) injury in diabetes is associated with oxidative stress, endothelial nitric oxide synthase (eNOS) dysfunction, and mitochondrial collapse, whereas luteolin is known to protect the cardiovascular system against diabetes and I/R injury. Here, we investigated whether luteolin pretreatment diminishes myocardial I/R injury in diabetic rats by affecting eNOS and the mitochondrial permeability transition pore (mPTP). After diabetic rats were produced by streptozotocin treatment (65 mg/kg) for 3 weeks, luteolin (100 mg·kg·d) or L-NAME (25 mg·kg·d) was administered intragastrically for 2 weeks. Hearts were then isolated and subjected to 30 minutes of global ischemia followed by 120 minutes of reperfusion. Pretreatment with luteolin significantly improved left ventricular function and coronary flow throughout reperfusion, increased cardiac tissue viability and manganese superoxide dismutase (MnSOD) activity, and reduced coronary lactate dehydrogenase release, and the myocardial malonaldehyde level in diabetic I/R rat hearts. All these improving effects of luteolin were significantly attenuated by L-NAME. Luteolin also significantly upregulated eNOS expression in diabetic rat hearts after I/R. Ca-induced mPTP opening and mitochondrial inner membrane potential reduction were significantly inhibited in ventricular myocytes isolated from luteolin-treated diabetic rats, and this effect was attenuated by L-NAME. These findings indicate that luteolin protects the diabetic heart against I/R injury by upregulating the myocardial eNOS pathway, and downstream effects include the enhancement of MnSOD and inhibition of mPTP. PMID:25502309

  5. Marine Compound Catunaregin Inhibits Angiogenesis through the Modulation of Phosphorylation of Akt and eNOS in vivo and in vitro

    PubMed Central

    Liu, Jun-Xiu; Luo, Min-Qi; Xia, Meng; Wu, Qi; Long, Si-Mei; Hu, Yaohua; Gao, Guang-Chun; Yao, Xiao-Li; He, Mian; Su, Huanxing; Luo, Xiong-Ming; Yao, Shu-Zhong

    2014-01-01

    Angiogenesis is the formation of blood vessels from pre-existing vasculature. Excessive or uncontrolled angiogenesis is a major contributor to many pathological conditions whereas inhibition of aberrant angiogenesis is beneficial to patients with pathological angiogenesis. Catunaregin is a core of novel marine compound isolated from mangrove associate. The potential anti-angiogenesis of catunaregin was investigated in human umbilical vein endothelial cells (HUVECs) and zebrafish. HUVECs were treated with different concentrations of catunaregin in the presence or absence of VEGF. The angiogenic phenotypes including cell invasion cell migration and tube formation were evaluated following catunaregin treatment in HUVECs. The possible involvement of AKT, eNOS and ERK1/2 in catunaregin-induced anti-angiogenesis was explored using Western blotting. The anti-angiogenesis of catunaregin was further tested in the zebrafish embryo neovascularization and caudal fin regeneration assays. We found that catunaregin dose-dependently inhibited angiogenesis in both HUVECs and zebrafish embryo neovascularization and zebrafish caudal fin regeneration assays. In addition, catunaregin significantly decreased the phosphorylation of Akt and eNOS, but not the phosphorylation of ERK1/2. The present work demonstrates that catunaregin exerts the anti-angiogenic activity at least in part through the regulation of the Akt and eNOS signaling pathways. PMID:24824025

  6. Marine compound catunaregin inhibits angiogenesis through the modulation of phosphorylation of akt and eNOS in vivo and in vitro.

    PubMed

    Liu, Jun-Xiu; Luo, Min-Qi; Xia, Meng; Wu, Qi; Long, Si-Mei; Hu, Yaohua; Gao, Guang-Chun; Yao, Xiao-Li; He, Mian; Su, Huanxing; Luo, Xiong-Ming; Yao, Shu-Zhong

    2014-05-01

    Angiogenesis is the formation of blood vessels from pre-existing vasculature. Excessive or uncontrolled angiogenesis is a major contributor to many pathological conditions whereas inhibition of aberrant angiogenesis is beneficial to patients with pathological angiogenesis. Catunaregin is a core of novel marine compound isolated from mangrove associate. The potential anti-angiogenesis of catunaregin was investigated in human umbilical vein endothelial cells (HUVECs) and zebrafish. HUVECs were treated with different concentrations of catunaregin in the presence or absence of VEGF. The angiogenic phenotypes including cell invasion cell migration and tube formation were evaluated following catunaregin treatment in HUVECs. The possible involvement of AKT, eNOS and ERK1/2 in catunaregin-induced anti-angiogenesis was explored using Western blotting. The anti-angiogenesis of catunaregin was further tested in the zebrafish embryo neovascularization and caudal fin regeneration assays. We found that catunaregin dose-dependently inhibited angiogenesis in both HUVECs and zebrafish embryo neovascularization and zebrafish caudal fin regeneration assays. In addition, catunaregin significantly decreased the phosphorylation of Akt and eNOS, but not the phosphorylation of ERK1/2. The present work demonstrates that catunaregin exerts the anti-angiogenic activity at least in part through the regulation of the Akt and eNOS signaling pathways.

  7. Cooperation of Doxycycline with Phytochemicals and Micronutrients Against Active and Persistent Forms of Borrelia sp

    PubMed Central

    Goc, Anna; Niedzwiecki, Alexandra; Rath, Matthias

    2016-01-01

    Phytochemicals and micronutrients represent a growing theme in antimicrobial defense; however, little is known about their anti-borreliae effects of reciprocal cooperation with antibiotics. A better understanding of this aspect could advance our knowledge and help improve the efficacy of current approaches towards Borrelia sp. In this study, phytochemicals and micronutrients such as baicalein, luteolin, 10-HAD, iodine, rosmarinic acid, and monolaurin, as well as, vitamins D3 and C were tested in a combinations with doxycycline for their in vitro effectiveness against vegetative (spirochetes) and latent (rounded bodies, biofilm) forms of Borrelia burgdorferi and Borrelia garinii. Anti-borreliae effects were evaluated according to checkerboard assays and supported by statistical analysis. The results showed that combination of doxycycline with flavones such as baicalein and luteolin exhibited additive effects against all morphological forms of studied Borrelia sp. Doxycycline combined with iodine demonstrated additive effects against spirochetes and biofilm, whereas with fatty acids such as monolaurin and 10-HAD it produced FICIs of indifference. Additive anti-spirochetal effects were also observed when doxycycline was used with rosmarinic acid and both vitamins D3 and C. Antagonism was not observed in any of the cases. This data revealed the intrinsic anti-borreliae activity of doxycycline with tested phytochemicals and micronutrients indicating that their addition may enhance efficacy of this antibiotic in combating Borrelia sp. Especially the addition of flavones balcalein and luteolin to a doxycycline regimen could be explored further in defining more effective treatments against these bacteria. PMID:27570483

  8. Flux Tensor Constrained Geodesic Active Contours with Sensor Fusion for Persistent Object Tracking

    PubMed Central

    Bunyak, Filiz; Palaniappan, Kannappan; Nath, Sumit Kumar; Seetharaman, Gunasekaran

    2007-01-01

    This paper makes new contributions in motion detection, object segmentation and trajectory estimation to create a successful object tracking system. A new efficient motion detection algorithm referred to as the flux tensor is used to detect moving objects in infrared video without requiring background modeling or contour extraction. The flux tensor-based motion detector when applied to infrared video is more accurate than thresholding ”hot-spots”, and is insensitive to shadows as well as illumination changes in the visible channel. In real world monitoring tasks fusing scene information from multiple sensors and sources is a useful core mechanism to deal with complex scenes, lighting conditions and environmental variables. The object segmentation algorithm uses level set-based geodesic active contour evolution that incorporates the fusion of visible color and infrared edge informations in a novel manner. Touching or overlapping objects are further refined during the segmentation process using an appropriate shape-based model. Multiple object tracking using correspondence graphs is extended to handle groups of objects and occlusion events by Kalman filter-based cluster trajectory analysis and watershed segmentation. The proposed object tracking algorithm was successfully tested on several difficult outdoor multispectral videos from stationary sensors and is not confounded by shadows or illumination variations. PMID:19096530

  9. Cooperation of Doxycycline with Phytochemicals and Micronutrients Against Active and Persistent Forms of Borrelia sp.

    PubMed

    Goc, Anna; Niedzwiecki, Alexandra; Rath, Matthias

    2016-01-01

    Phytochemicals and micronutrients represent a growing theme in antimicrobial defense; however, little is known about their anti-borreliae effects of reciprocal cooperation with antibiotics. A better understanding of this aspect could advance our knowledge and help improve the efficacy of current approaches towards Borrelia sp. In this study, phytochemicals and micronutrients such as baicalein, luteolin, 10-HAD, iodine, rosmarinic acid, and monolaurin, as well as, vitamins D3 and C were tested in a combinations with doxycycline for their in vitro effectiveness against vegetative (spirochetes) and latent (rounded bodies, biofilm) forms of Borrelia burgdorferi and Borrelia garinii. Anti-borreliae effects were evaluated according to checkerboard assays and supported by statistical analysis. The results showed that combination of doxycycline with flavones such as baicalein and luteolin exhibited additive effects against all morphological forms of studied Borrelia sp. Doxycycline combined with iodine demonstrated additive effects against spirochetes and biofilm, whereas with fatty acids such as monolaurin and 10-HAD it produced FICIs of indifference. Additive anti-spirochetal effects were also observed when doxycycline was used with rosmarinic acid and both vitamins D3 and C. Antagonism was not observed in any of the cases. This data revealed the intrinsic anti-borreliae activity of doxycycline with tested phytochemicals and micronutrients indicating that their addition may enhance efficacy of this antibiotic in combating Borrelia sp. Especially the addition of flavones balcalein and luteolin to a doxycycline regimen could be explored further in defining more effective treatments against these bacteria. PMID:27570483

  10. Defective disposal of immune complexes and polyclonal B cell activation persist long after exposure to bacterial lipopolysaccharide in mice

    SciTech Connect

    Granholm, N.A.; Cavallo, T. )

    1989-11-01

    Patients with systemic lupus erythematosus experience clinical exacerbation during superimposed bacterial infection. Previous studies in mice indicated that heightened immune phenomena during exposure to bacterial lipopolysaccharide (LPS) appear to be related, in part, to polyclonal B cell activation, to abnormal disposal of immune complexes (IC), and to increased localization of IC in tissues. To investigate whether such effects were reversible, we administered bacterial LPS to C57BL/6 mice for 5 weeks. Control mice received vehicle alone. We then discontinued LPS, and 6 weeks later LPS and control mice were challenged with a subsaturating dose of radiolabeled IC; the removal of IC from the circulation, their localization in the liver, spleen, and kidney were determined. In comparison to values in control mice, in mice previously exposed to LPS, serologic features of polyclonal B cell activation persisted; liver uptake of pathogenic IC (greater than Ag2Ab2) was normal, but removal of small size IC (less than or equal to Ag2Ab2) from the circulation was delayed; localization of IC in the kidneys was enhanced, and pathologic proteinuria developed. The effects of repeated exposure to bacterial LPS are partially reversible, but they last long after LPS is discontinued and may contribute to altered disposal of IC, enhanced organ localization of IC, and organ dysfunction.

  11. Student Characteristics and Activity Choices of College Freshmen and Their Intent to Persist in Religiously Affiliated Institutions

    ERIC Educational Resources Information Center

    Burks, Stephen A.; Barrett, T. Gregory

    2009-01-01

    Persistence and retention have been studied extensively in higher education, but little research has been conducted on these areas in religiously affiliated institutions. The present study was designed to examine factors that influence the intentions of students to persist from their freshmen to sophomore year in private, religiously affiliated,…

  12. The inverse agonist propranolol confers no corticosteroid-sparing activity in mild-to-moderate persistent asthma.

    PubMed

    Anderson, William J; Short, Philip M; Williamson, Peter A; Manoharan, Arvind; Lipworth, Brian J

    2014-12-01

    The murine asthma model shows that switching off airway β2 receptors with an inverse agonist may confer anti-inflammatory effects as well as corticosteroid-sparing activity. We have assessed for any corticosteroid-sparing effects of propranolol, an inverse agonist, added to low-dose inhaled corticosteroid (ICS) compared with higher dose ICS. A randomized double-blind placebo-controlled cross-over trial in mild-to-moderate persistent asthmatic patients was performed. After a run-in (2 weeks) on hydrofluoroalkane-beclometasone dipropionate (HFA-BDP) at 100 μg/day (HFA-BDP100), patients received randomized treatments (4 weeks) with propranolol at 80 mg/day plus HFA-BDP at 100 μg/day compared with placebo plus HFA-BDP at 400 μg/day (HFA-BDP400). Propranolol was up-titrated to 80 mg/day over the initial 2 weeks. Tiotropium was co-administered until 5 days before each histamine challenge (the primary outcome). Sixteen patients completed the study [mean age, 38 years; forced expiratory volume in 1 s (FEV1), 86.4%; histamine provocative concentration causing a 20% fall in FEV1 (PC20), 1.39 mg/ml; ICS dose, 406 μg/day]. Histamine PC20 was unchanged by adding propranolol to HFA-BDP100 compared with baseline (HFA-BDP100) {0.17 doubling dilution (dd) difference [95% confidence interval (CI): -0.58 to 0.92]}, but there was a significant improvement with HFA-BDP400 compared with both baseline [1.05 dd (95% CI: 0.43-1.66); P=0.02], and propranolol+HFA-BDP100 [0.88 dd (95% CI: 0.45-1.30); P=0.006]. Significant improvements were also observed with HFA-BDP400 for exhaled nitric oxide, blood eosinophils, serum eosinophilic cationic protein and asthma quality-of-life questionnaire symptoms compared with propranolol+HFA-BDP100. Salbutamol recovery post-challenge was partially blunted by propranolol (median prolongation 5 min; P=0.002). Domiciliary evening FEV1 also fell with propranolol+HFA-BDP100 [mean reduction from baseline 0.22 litres (95% CI: 0.10-0.34); P=0.012], whereas

  13. Endothelial nitric oxide synthase (eNOS) gene polymorphism in early term chronic allograft nephropathy.

    PubMed

    Yilmaz, E; Mir, S; Berdeli, A

    2009-12-01

    Chronic allograft nephropathy (CAN) is a complex phenomenon caused by underlying kidney disease with superimposed enviromental and genetic factors. CAN development begins with progressive renal microvascular injury. Endothelial cells play key roles in the regulation of vascular tone, permeability, and remodeling. A reduction in basal nitric oxide (NO) release as a result of genetic variation in endothelial NO synthase (eNOS) function may predispose to hypertension, thrombosis, vasospasm, and atherosclerosis, all contributing to the development of CAN. We analyzed the G894T mutation at exon 7 of the eNOS gene in relationship to CAN among 81 children with renal transplantations. The 20 patients who developed CAN underwent renal biopsies for histological confirmation. Proteinuria and hypertension were observed in CAN. We selected 173 healthy reference subjects. The G894T polymorphism of the eNOS gene was determined by PCR-restriction fragment-length polymorphism analysis. The group included 33 male and 48 female subjects who received 32 living-related grafts and 49 from deceased donors (DD) donors. Donor age (y) was 32.7 +/- 13.7 and the HLA A,B,DR mismatch number of the cadaveric cases was 3.5 +/- 0.79. The distribution of the genotypes were ENOS GG/GT/TT 48%, 33%, 19%, respectively. G-alleles frequency was 64.8%; T-allele frequency was 35.2%. ENOS G894T gene polymorphism did not seem to influence long-term renal allograft outcome. Recipient ENOS G894T gene polymorphism did not alter the risk of chronic allograft failure. Even if NO synthesis and bioactivity are influenced by this polymorphism, many vasoactive factors may have roles to suppress the advantageous effects of NO. PMID:20005399

  14. A Drug Combination Screen Identifies Drugs Active against Amoxicillin-Induced Round Bodies of In Vitro Borrelia burgdorferi Persisters from an FDA Drug Library

    PubMed Central

    Feng, Jie; Shi, Wanliang; Zhang, Shuo; Sullivan, David; Auwaerter, Paul G.; Zhang, Ying

    2016-01-01

    Although currently recommended antibiotics for Lyme disease such as doxycycline or amoxicillin cure the majority of the patients, about 10–20% of patients treated for Lyme disease may experience lingering symptoms including fatigue, pain, or joint and muscle aches. Under experimental stress conditions such as starvation or antibiotic exposure, Borrelia burgdorferi can develop round body forms, which are a type of persister bacteria that appear resistant in vitro to customary first-line antibiotics for Lyme disease. To identify more effective drugs with activity against the round body form of B. burgdorferi, we established a round body persister model induced by exposure to amoxicillin (50 μg/ml) and then screened the Food and Drug Administration drug library consisting of 1581 drug compounds and also 22 drug combinations using the SYBR Green I/propidium iodide viability assay. We identified 23 drug candidates that have higher activity against the round bodies of B. burgdorferi than either amoxicillin or doxycycline. Eleven individual drugs scored better than metronidazole and tinidazole which have been previously described to be active against round bodies. In this amoxicillin-induced round body model, some drug candidates such as daptomycin and clofazimine also displayed enhanced activity which was similar to a previous screen against stationary phase B. burgdorferi persisters not exposure to amoxicillin. Additional candidate drugs active against round bodies identified include artemisinin, ciprofloxacin, nifuroxime, fosfomycin, chlortetracycline, sulfacetamide, sulfamethoxypyridazine and sulfathiozole. Two triple drug combinations had the highest activity against amoxicillin-induced round bodies and stationary phase B. burgdorferi persisters: artemisinin/cefoperazone/doxycycline and sulfachlorpyridazine/daptomycin/doxycycline. These findings confirm and extend previous findings that certain drug combinations have superior activity against B. burgdorferi

  15. Distinct expression of alkaline phosphatase activity in epilimnetic bacteria: Implication for persistent DOC consumption in a P-limited reservoir

    NASA Astrophysics Data System (ADS)

    Tseng, Y.; Kao, S.; Shiah, F.

    2013-12-01

    In a P-deficient system, P availability usually controls the microbial activity and thus the ecosystem function. Thingstad et al. (1997) first addressed a 'Malfunctioning Microbial-loop' theory, which stated that low bacterial production (BP) caused by insufficient nutrient supply would result in DOC accumulation in an oligotrophic ecosystem. In this study we re-examined the theory by conducting seasonal patterns and correlations among soluble reactive phosphate (SRP) and DOC, microbial abundances (picocyanobacteria, bacteria, and heterotrophic nanoflagellate; HNF) and activities (primary production, bacterial production, and alkaline phosphatase activity; APA) coupled with enzyme-labeled fluorescence (ELF) assays on bacterioplankton in a subtropical reservoir sharing the common features, nitrate-replete and P-deficient, with most natural freshwater system during Oct 2007-Oct 2008. Persistently high APA was recorded during most of time, implying that the system was P-deficient. Size fractionated APA and ELF assay revealed that bacteria were the major APA contributor. However, significantly low epilimnion DOC was recorded during the stratified summer season accompanying with high BP and APA as well as high PP, implying that heterotrophic bacteria can well sustain in P-deficient system by utilizing DOP to rapidly lower down DOC under relatively high PP. Such findings oppose the 'Malfunctioning Microbial-loop' theory. On the other hand, strong epilimnetic DOC accumulation occurred in Oct 2007 under low light and low PP condition accompanying with high abundance of HNF, implying that HNF grazing may contribute to a certain degree of DOC accumulation. Correlation matrix supported our suggestions. This study testified the DOC dynamics in P-deficient ecosystem are tightly coupled with the source (PP and grazing) and sink (BP). We also suggested that in SRP-limited freshwater systems bacteria are capable of breaking down autochthonous DOC to reduce the chance of DOC

  16. eNOS uncoupling in the cerebellum after BBB disruption by exposure to Phoneutria nigriventer spider venom.

    PubMed

    Soares, Edilene Siqueira; Mendonça, Monique Culturato Padilha; da Cruz-Höfling, Maria Alice

    2015-09-15

    Numerous studies have shown that the venom of Phoneutria nigriventer (PNV) armed-spider causes excitotoxic signals and blood-brain barrier breakdown (BBBb) in rats. Nitric oxide (NO) is a signaling molecule which has a role in endothelium homeostasis and vascular health. The present study investigated the relevance of endothelial NO synthase (eNOS) uncoupling to clinical neurotoxic evolution induced by PNV. eNOS immunoblotting of cerebellum lysates processed through low-temperature SDS-PAGE revealed significant increased monomerization of the enzyme at critical periods of severe envenoming (1-2 h), whereas eNOS dimerization reversal paralleled to amelioration of animals condition (5-72 h). Moreover, eNOS uncoupling was accompanied by increased expression in calcium-sensing calmodulin protein and calcium-binding calbindin-D28 protein in cerebellar neurons. It is known that greater eNOS monomers than dimers implies the inability of eNOS to produce NO leading to superoxide production and endothelial/vascular barrier dysfunction. We suggest that transient eNOS deactivation and disturbances in calcium handling reduce NO production and enhance production of free radicals thus contributing to endothelial dysfunction in the cerebellum of envenomed rats. In addition, eNOS uncoupling compromises the enzyme capacity to respond to shear stress contributing to perivascular edema and it is one of the mechanisms involved in the BBBb promoted by PNV.

  17. Indonesian fire activity and smoke pollution in 2015 show persistent nonlinear sensitivity to El Niño-induced drought

    NASA Astrophysics Data System (ADS)

    Field, Robert D.; van der Werf, Guido R.; Fanin, Thierry; Fetzer, Eric J.; Fuller, Ryan; Jethva, Hiren; Levy, Robert; Livesey, Nathaniel J.; Luo, Ming; Torres, Omar; Worden, Helen M.

    2016-08-01

    The 2015 fire season and related smoke pollution in Indonesia was more severe than the major 2006 episode, making it the most severe season observed by the NASA Earth Observing System satellites that go back to the early 2000s, namely active fire detections from the Terra and Aqua Moderate Resolution Imaging Spectroradiometers (MODIS), MODIS aerosol optical depth, Terra Measurement of Pollution in the Troposphere (MOPITT) carbon monoxide (CO), Aqua Atmospheric Infrared Sounder (AIRS) CO, Aura Ozone Monitoring Instrument (OMI) aerosol index, and Aura Microwave Limb Sounder (MLS) CO. The MLS CO in the upper troposphere showed a plume of pollution stretching from East Africa to the western Pacific Ocean that persisted for 2 mo. Longer-term records of airport visibility in Sumatra and Kalimantan show that 2015 ranked after 1997 and alongside 1991 and 1994 as among the worst episodes on record. Analysis of yearly dry season rainfall from the Tropical Rainfall Measurement Mission (TRMM) and rain gauges shows that, due to the continued use of fire to clear and prepare land on degraded peat, the Indonesian fire environment continues to have nonlinear sensitivity to dry conditions during prolonged periods with less than 4 mm/d of precipitation, and this sensitivity appears to have increased over Kalimantan. Without significant reforms in land use and the adoption of early warning triggers tied to precipitation forecasts, these intense fire episodes will reoccur during future droughts, usually associated with El Niño events.

  18. Indonesian fire activity and smoke pollution in 2015 show persistent nonlinear sensitivity to El Niño-induced drought.

    PubMed

    Field, Robert D; van der Werf, Guido R; Fanin, Thierry; Fetzer, Eric J; Fuller, Ryan; Jethva, Hiren; Levy, Robert; Livesey, Nathaniel J; Luo, Ming; Torres, Omar; Worden, Helen M

    2016-08-16

    The 2015 fire season and related smoke pollution in Indonesia was more severe than the major 2006 episode, making it the most severe season observed by the NASA Earth Observing System satellites that go back to the early 2000s, namely active fire detections from the Terra and Aqua Moderate Resolution Imaging Spectroradiometers (MODIS), MODIS aerosol optical depth, Terra Measurement of Pollution in the Troposphere (MOPITT) carbon monoxide (CO), Aqua Atmospheric Infrared Sounder (AIRS) CO, Aura Ozone Monitoring Instrument (OMI) aerosol index, and Aura Microwave Limb Sounder (MLS) CO. The MLS CO in the upper troposphere showed a plume of pollution stretching from East Africa to the western Pacific Ocean that persisted for 2 mo. Longer-term records of airport visibility in Sumatra and Kalimantan show that 2015 ranked after 1997 and alongside 1991 and 1994 as among the worst episodes on record. Analysis of yearly dry season rainfall from the Tropical Rainfall Measurement Mission (TRMM) and rain gauges shows that, due to the continued use of fire to clear and prepare land on degraded peat, the Indonesian fire environment continues to have nonlinear sensitivity to dry conditions during prolonged periods with less than 4 mm/d of precipitation, and this sensitivity appears to have increased over Kalimantan. Without significant reforms in land use and the adoption of early warning triggers tied to precipitation forecasts, these intense fire episodes will reoccur during future droughts, usually associated with El Niño events. PMID:27482096

  19. Indonesian fire activity and smoke pollution in 2015 show persistent nonlinear sensitivity to El Niño-induced drought.

    PubMed

    Field, Robert D; van der Werf, Guido R; Fanin, Thierry; Fetzer, Eric J; Fuller, Ryan; Jethva, Hiren; Levy, Robert; Livesey, Nathaniel J; Luo, Ming; Torres, Omar; Worden, Helen M

    2016-08-16

    The 2015 fire season and related smoke pollution in Indonesia was more severe than the major 2006 episode, making it the most severe season observed by the NASA Earth Observing System satellites that go back to the early 2000s, namely active fire detections from the Terra and Aqua Moderate Resolution Imaging Spectroradiometers (MODIS), MODIS aerosol optical depth, Terra Measurement of Pollution in the Troposphere (MOPITT) carbon monoxide (CO), Aqua Atmospheric Infrared Sounder (AIRS) CO, Aura Ozone Monitoring Instrument (OMI) aerosol index, and Aura Microwave Limb Sounder (MLS) CO. The MLS CO in the upper troposphere showed a plume of pollution stretching from East Africa to the western Pacific Ocean that persisted for 2 mo. Longer-term records of airport visibility in Sumatra and Kalimantan show that 2015 ranked after 1997 and alongside 1991 and 1994 as among the worst episodes on record. Analysis of yearly dry season rainfall from the Tropical Rainfall Measurement Mission (TRMM) and rain gauges shows that, due to the continued use of fire to clear and prepare land on degraded peat, the Indonesian fire environment continues to have nonlinear sensitivity to dry conditions during prolonged periods with less than 4 mm/d of precipitation, and this sensitivity appears to have increased over Kalimantan. Without significant reforms in land use and the adoption of early warning triggers tied to precipitation forecasts, these intense fire episodes will reoccur during future droughts, usually associated with El Niño events.

  20. Hybrid coordination-network-engineering for bridging cascaded channels to activate long persistent phosphorescence in the second biological window

    NASA Astrophysics Data System (ADS)

    Qin, Xixi; Li, Yang; Zhang, Ruili; Ren, Jinjun; Gecevicius, Mindaugas; Wu, Yiling; Sharafudeen, Kaniyarakkal; Dong, Guoping; Zhou, Shifeng; Ma, Zhijun; Qiu, Jianrong

    2016-02-01

    We present a novel “Top-down” strategy to design the long phosphorescent phosphors in the second biological transparency window via energy transfer. Inherence in this approach to material design involves an ingenious engineering for hybridizing the coordination networks of hosts, tailoring the topochemical configuration of dopants, and bridging a cascaded tunnel for transferring the persistent energy from traps, to sensitizers and then to acceptors. Another significance of this endeavour is to highlight a rational scheme for functionally important hosts and dopants, Cr/Nd co-doped Zn1-xCaxGa2O4 solid solutions. Such solid-solution is employed as an optimized host to take advantage of its characteristic trap site level to establish an electron reservoir and network parameters for the precipitation of activators Nd3+ and Cr3+. The results reveal that the strategy employed here has the great potential, as well as opens new opportunities for future new-wavelength, NIR phosphorescent phosphors fabrication with many potential multifunctional bio-imaging applications.

  1. Q-Learning and p-persistent CSMA based rendezvous protocol for cognitive radio networks operating with shared spectrum activity

    NASA Astrophysics Data System (ADS)

    Watson, Clifton L.; Biswas, Subir

    2014-06-01

    With an increasing demand for spectrum, dynamic spectrum access (DSA) has been proposed as viable means for providing the flexibility and greater access to spectrum necessary to meet this demand. Within the DSA concept, unlicensed secondary users temporarily "borrow" or access licensed spectrum, while respecting the licensed primary user's rights to that spectrum. As key enablers for DSA, cognitive radios (CRs) are based on software-defined radios which allow them to sense, learn, and adapt to the spectrum environment. These radios can operate independently and rapidly switch channels. Thus, the initial setup and maintenance of cognitive radio networks are dependent upon the ability of CR nodes to find each other, in a process known as rendezvous, and create a link on a common channel for the exchange of data and control information. In this paper, we propose a novel rendezvous protocol, known as QLP, which is based on Q-learning and the p-persistent CSMA protocol. With the QLP protocol, CR nodes learn which channels are best for rendezvous and thus adapt their behavior to visit those channels more frequently. We demonstrate through simulation that the QLP protocol provides a rendevous capability for DSA environments with different dynamics of PU activity, while attempting to achieve the following performance goals: (1) minimize the average time-to-rendezvous, (2) maximize system throughput, (3) minimize primary user interference, and (4) minimize collisions among CR nodes.

  2. Hybrid coordination-network-engineering for bridging cascaded channels to activate long persistent phosphorescence in the second biological window

    PubMed Central

    Qin, Xixi; Li, Yang; Zhang, Ruili; Ren, Jinjun; Gecevicius, Mindaugas; Wu, Yiling; Sharafudeen, Kaniyarakkal; Dong, Guoping; Zhou, Shifeng; Ma, Zhijun; Qiu, Jianrong

    2016-01-01

    We present a novel “Top-down” strategy to design the long phosphorescent phosphors in the second biological transparency window via energy transfer. Inherence in this approach to material design involves an ingenious engineering for hybridizing the coordination networks of hosts, tailoring the topochemical configuration of dopants, and bridging a cascaded tunnel for transferring the persistent energy from traps, to sensitizers and then to acceptors. Another significance of this endeavour is to highlight a rational scheme for functionally important hosts and dopants, Cr/Nd co-doped Zn1−xCaxGa2O4 solid solutions. Such solid-solution is employed as an optimized host to take advantage of its characteristic trap site level to establish an electron reservoir and network parameters for the precipitation of activators Nd3+ and Cr3+. The results reveal that the strategy employed here has the great potential, as well as opens new opportunities for future new-wavelength, NIR phosphorescent phosphors fabrication with many potential multifunctional bio-imaging applications. PMID:26843129

  3. Target sequencing, cell experiments, and a population study establish endothelial nitric oxide synthase (eNOS) gene as hypertension susceptibility gene.

    PubMed

    Salvi, Erika; Kuznetsova, Tatiana; Thijs, Lutgarde; Lupoli, Sara; Stolarz-Skrzypek, Katarzyna; D'Avila, Francesca; Tikhonoff, Valerie; De Astis, Silvia; Barcella, Matteo; Seidlerová, Jitka; Benaglio, Paola; Malyutina, Sofia; Frau, Francesca; Velayutham, Dinesh; Benfante, Roberta; Zagato, Laura; Title, Alexandra; Braga, Daniele; Marek, Diana; Kawecka-Jaszcz, Kalina; Casiglia, Edoardo; Filipovsky, Jan; Nikitin, Yuri; Rivolta, Carlo; Manunta, Paolo; Beckmann, Jacques S; Barlassina, Cristina; Cusi, Daniele; Staessen, Jan A

    2013-11-01

    A case-control study revealed association between hypertension and rs3918226 in the endothelial nitric oxide synthase (eNOS) gene promoter (minor/major allele, T/C allele). We aimed at substantiating these preliminary findings by target sequencing, cell experiments, and a population study. We sequenced the 140-kb genomic area encompassing the eNOS gene. In HeLa and HEK293T cells transfected with the eNOS promoter carrying either the T or the C allele, we quantified transcription by luciferase assay. In 2722 randomly recruited Europeans (53.0% women; mean age 40.1 years), we studied blood pressure change and incidence of hypertension in relation to rs3918226, using multivariable-adjusted models. Sequencing confirmed rs3918226, a binding site of E-twenty six transcription factors, as the single nucleotide polymorphism most closely associated with hypertension. In T compared with C transfected cells, eNOS promoter activity was from 20% to 40% (P<0.01) lower. In the population, systolic/diastolic blood pressure increased over 7.6 years (median) by 9.7/6.8 mm Hg in 28 TT homozygotes and by 3.8/1.9 mm Hg in 2694 C allele carriers (P≤0.0004). The blood pressure rise was 5.9 mm Hg systolic (confidence interval [CI], 0.6-11.1; P=0.028) and 4.8 mm Hg diastolic (CI, 1.5-8.2; P=0.0046) greater in TT homozygotes, with no differences between the CT and CC genotypes (P≥0.90). Among 2013 participants normotensive at baseline, 692 (34.4%) developed hypertension. The hazard ratio and attributable risk associated with TT homozygosity were 2.04 (CI, 1.24-3.37; P=0.0054) and 51.0%, respectively. In conclusion, rs3918226 in the eNOS promoter tags a hypertension susceptibility locus, TT homozygosity being associated with lesser transcription and higher risk of hypertension.

  4. Target sequencing, cell experiments, and a population study establish endothelial nitric oxide synthase (eNOS) gene as hypertension susceptibility gene.

    PubMed

    Salvi, Erika; Kuznetsova, Tatiana; Thijs, Lutgarde; Lupoli, Sara; Stolarz-Skrzypek, Katarzyna; D'Avila, Francesca; Tikhonoff, Valerie; De Astis, Silvia; Barcella, Matteo; Seidlerová, Jitka; Benaglio, Paola; Malyutina, Sofia; Frau, Francesca; Velayutham, Dinesh; Benfante, Roberta; Zagato, Laura; Title, Alexandra; Braga, Daniele; Marek, Diana; Kawecka-Jaszcz, Kalina; Casiglia, Edoardo; Filipovsky, Jan; Nikitin, Yuri; Rivolta, Carlo; Manunta, Paolo; Beckmann, Jacques S; Barlassina, Cristina; Cusi, Daniele; Staessen, Jan A

    2013-11-01

    A case-control study revealed association between hypertension and rs3918226 in the endothelial nitric oxide synthase (eNOS) gene promoter (minor/major allele, T/C allele). We aimed at substantiating these preliminary findings by target sequencing, cell experiments, and a population study. We sequenced the 140-kb genomic area encompassing the eNOS gene. In HeLa and HEK293T cells transfected with the eNOS promoter carrying either the T or the C allele, we quantified transcription by luciferase assay. In 2722 randomly recruited Europeans (53.0% women; mean age 40.1 years), we studied blood pressure change and incidence of hypertension in relation to rs3918226, using multivariable-adjusted models. Sequencing confirmed rs3918226, a binding site of E-twenty six transcription factors, as the single nucleotide polymorphism most closely associated with hypertension. In T compared with C transfected cells, eNOS promoter activity was from 20% to 40% (P<0.01) lower. In the population, systolic/diastolic blood pressure increased over 7.6 years (median) by 9.7/6.8 mm Hg in 28 TT homozygotes and by 3.8/1.9 mm Hg in 2694 C allele carriers (P≤0.0004). The blood pressure rise was 5.9 mm Hg systolic (confidence interval [CI], 0.6-11.1; P=0.028) and 4.8 mm Hg diastolic (CI, 1.5-8.2; P=0.0046) greater in TT homozygotes, with no differences between the CT and CC genotypes (P≥0.90). Among 2013 participants normotensive at baseline, 692 (34.4%) developed hypertension. The hazard ratio and attributable risk associated with TT homozygosity were 2.04 (CI, 1.24-3.37; P=0.0054) and 51.0%, respectively. In conclusion, rs3918226 in the eNOS promoter tags a hypertension susceptibility locus, TT homozygosity being associated with lesser transcription and higher risk of hypertension. PMID:24019403

  5. Faults Activities And Crustal Deformation near Hualien City, eastern Taiwan Analysed By Persistent Scatterer InSAR

    NASA Astrophysics Data System (ADS)

    Lu, C.; Lin, M.; Yen, J.; Chang, C.

    2008-12-01

    Hualien is located in eastern part of Taiwan, and is the collision boundary in the northern of Huatung Longitudinal Valley between the Philippine Sea tectonic plate and Eurasian tectonic plate(Biq, 1981; Barrier and Angelier, 1986). There are several active faults, such as Milun fault, Beipu fault and Minyi fault, pass through the Hualien city, and create many crustal deformation. According to previous researches (Hsu, 1956; Lin, 1962; Yu, 1997) we know Milun fault is a thrust and left lateral fault, and the fault plane incline to east. Minyi fault also is a left lateral and a slight reverse fault, but it's fault plane incline to west. (Chang, 1994; Yu, 1997) We applied the Persistent Scatterer Interferometric Synthetic Aperture Radar (PSInSAR, Hooper, 2007) to observe temporally-variable processes of Hualien city between 2004 to 2008. At the same time, precise leveling and GPS data were taken for the auxiliary data to verify the deformation rate and pattern in this area. In the Hualien city area, our observation showed that the active faults separate this area into several distinct blocks. Most of the blocks moved slowly, but the hanging wall of the Milun fault decreases 5- 8mm in line of sight (LOS) direction between 15 May 2004 to 24 Feb 2007, then increases 3-6mm in LOS between 1 Dec 2007 to 5 Jan 2008. The deformation reversed its direction in 2007. The western surface of Hualien City displays continuous deformation about 1.5-2mm/yr , which spread along the Beipu fault. Our preliminary investigation indicated that between late 2004 and middle 2005 there had been an abrupt increase in seismicity, which coincided with PSInSAR observation of a large displacement. The distribution of shallow source earthquakes correlate with the area with large deformation. Our following works include continuing observation of the Hualien City, and decipher the relationship between earthquakes and surface deformation, and model the fault action in Hualien City with time series.

  6. Faults Activities And Crustal Deformation Along The Arc-Continent Collision Boundary, Eastern Taiwan - Observed From Persistent Scatterer SAR Interferometry

    NASA Astrophysics Data System (ADS)

    Yen, Jiun-Yee; Chang, Chung-Pai; Hooper, Andrew; Chang, Yo-Ho; Liang, Wen-Tzong; Chang, Tsui-Yu

    2010-05-01

    Located in the southeastern periphery of the Eurasian plate, eastern Taiwan marks the collional boundary between the Eurasian plate and the Philippine Sea plate. These two plates converge at about 8 cm/yr near Taiwan and nearly half of the shortening is consumed in eastern Taiwan. There have been many studies in this area about the dynamics of the plate convergence, however, most of the geodetic studies focused on small area (strainmeter), with very few data points (GPS), or only gather data along a specific profile (leveling). We applied the Persistent Scatterer SAR Interferometry in the Longitudinal Valley of eastern Taiwan to observe temporally-variable processes using both ERS and Envisat data. At the same time, leveling and GPS data were measured for the auxiliary tool to verify the deformation rate in this area. Our result indicated that although the area is under active collision, faults do not move in the same fashion along the boundary. In the very northern part of the collided arc, small subsidence has been detected, while in the north-central part very few activity is observed. In the central and southern part of the collisional boundary, patches of faults are moving as rapidly as 15 mm/yr along radar line-of-sight. In addition. between late 2004 and middle 2005 there had been an earthquake swarm consists of shallow earthquakes, which coincided with PSI observation of a large vertical displacement. The comparison between our leveling data and PS results indicated PSI is a reliable tool even in the highly vegetated area in eastern Taiwan.

  7. The Serra de Tramuntana World Heritage Site (Mallorca, Spain). Landslide activity valuation by means of Persistent Scatterers Interferometry

    NASA Astrophysics Data System (ADS)

    Mateos, Rosa Maria; Bianchini, Silvia; Herrera, Gerardo; Garcia, Inmaculada; Sanabria, Margarita

    2016-04-01

    The Serra de Tramuntana, which forms the backbone of the north-west of Mallorca (Spain), was declared in 2011 World Heritage Site by UNESCO under the cultural landscape category. The particular landscape of this range is the fruit of the exchange of knowledge between cultures, with small-scale works performed collectively for a productive aim, conditioned by the limitations imposed by the physical medium. The steep topography of the chain, highly related to its geological complexity, and the Mediterranean climate, influence intense slope dynamics with the consequent multiple types of slope failures: rock slides, earth landslides and rockfalls, which cause significant damage and specifically to the road network (Mateos, 2013a). The human landscape marked by agricultural terraces (dry stone constructions) has significantly contributed to the slope stability in the range for centuries. In the present work, a landslide inventory map with 918 events has been updated and the landslides state of activity was analyzed exploiting 14 ALOS PALSAR satellite SAR (Synthetic Aperture Radar) images acquired during the period 2007-2010. Landslide activity maps were elaborated through the use of PSI (Persistent Scatterers Interferometry) technique (Bianchini et al., 2013). Besides assessing the PS visibility of the study area according to the relief, land use and satellite acquisition parameters, these maps evaluate, for every monitored landslide, the average velocities along the satellite Line Of Sight (VLOS) and along the maximum local steepest slope (VSLOPE), providing an estimate of their state of activity and their potential to cause damages. Additionally, a ground motion activity map is also generated, based on active PS clusters not included within any mapped landslide phenomenon. A confidence degree evaluation is carried out to attest the reliability of measured displacements to represent landslide dynamics. Results show that 42 landslides were identified as active (VSLOPE

  8. The Serra de Tramuntana World Heritage Site (Mallorca, Spain). Landslide activity valuation by means of Persistent Scatterers Interferometry

    NASA Astrophysics Data System (ADS)

    Mateos, Rosa Maria; Bianchini, Silvia; Herrera, Gerardo; Garcia, Inmaculada; Sanabria, Margarita

    2016-04-01

    The Serra de Tramuntana, which forms the backbone of the north-west of Mallorca (Spain), was declared in 2011 World Heritage Site by UNESCO under the cultural landscape category. The particular landscape of this range is the fruit of the exchange of knowledge between cultures, with small-scale works performed collectively for a productive aim, conditioned by the limitations imposed by the physical medium. The steep topography of the chain, highly related to its geological complexity, and the Mediterranean climate, influence intense slope dynamics with the consequent multiple types of slope failures: rock slides, earth landslides and rockfalls, which cause significant damage and specifically to the road network (Mateos, 2013a). The human landscape marked by agricultural terraces (dry stone constructions) has significantly contributed to the slope stability in the range for centuries. In the present work, a landslide inventory map with 918 events has been updated and the landslides state of activity was analyzed exploiting 14 ALOS PALSAR satellite SAR (Synthetic Aperture Radar) images acquired during the period 2007-2010. Landslide activity maps were elaborated through the use of PSI (Persistent Scatterers Interferometry) technique (Bianchini et al., 2013). Besides assessing the PS visibility of the study area according to the relief, land use and satellite acquisition parameters, these maps evaluate, for every monitored landslide, the average velocities along the satellite Line Of Sight (VLOS) and along the maximum local steepest slope (VSLOPE), providing an estimate of their state of activity and their potential to cause damages. Additionally, a ground motion activity map is also generated, based on active PS clusters not included within any mapped landslide phenomenon. A confidence degree evaluation is carried out to attest the reliability of measured displacements to represent landslide dynamics. Results show that 42 landslides were identified as active (VSLOPE

  9. Burst and Persistent Emission Properties during the Recent Active Episode of the Anomalous X-Ray Pulsar 1E 1841-045

    NASA Technical Reports Server (NTRS)

    Lin, Lin; Kouveliotou, Chryssa; Gogus, Ersin; van der Horst, Alexander J.; Watts, Anna L.; Baring, Matthew G.; Kaneko, Yuki; Wijers, Ralph A. M. J.; Woods, Peter M.; Barthelmy, Scott; Burgess, J. Michael; Chaplin, Vandiver; Gehrels, Neil; Goldstein, Adam; Granot, Jonathan; Guiriec, Sylvain; Mcenery, Julie; Preece, Robert D.; Tierney, David; van der Klis, Michiel; von Kienlin, Andreas; Zhang, Shuang Nan

    2011-01-01

    SWift/BAT detected the first burst from 1E 1841-045 in May 2010 with intermittent burst activity recorded through at least July 2011. Here we present Swift and Fermi/GBM observations of this burst activity and search for correlated changes to the persistent X-ray emission of the source. The T90 durations of the bursts range between 18 - 140 ms, comparable to other magnetar burst durations, while the energy released in each burst ranges between (0.8-25) x 1038 erg, which is in the low side of SGR bursts. We find that the bursting activity did not have a significant effect on the persistent flux level of the source. We argue that the mechanism leading to this sporadic burst activity in IE 1841-045 might not involve large scale restructuring (either crustal or magnetospheric) as seen in other magnetar sources.

  10. Burst and Persistent Emission Properties during the Recent Active Episode of the Anomalous X-Ray Pulsar 1E 1841-045

    NASA Astrophysics Data System (ADS)

    Lin, Lin; Kouveliotou, Chryssa; Göǧüş, Ersin; van der Horst, Alexander J.; Watts, Anna L.; Baring, Matthew G.; Kaneko, Yuki; Wijers, Ralph A. M. J.; Woods, Peter M.; Barthelmy, Scott; Burgess, James Michael; Chaplin, Vandiver; Gehrels, Neil; Goldstein, Adam; Granot, Jonathan; Guiriec, Sylvain; Mcenery, Julie; Preece, Robert D.; Tierney, David; van der Klis, Michiel; von Kienlin, Andreas; Zhang, Shuang Nan

    2011-10-01

    The Swift/Burst Alert Telescope detected the first burst from 1E 1841-045 in 2010 May with intermittent burst activity recorded through at least 2011 July. Here we present Swift and Fermi/Gamma-ray Burst Monitor observations of this burst activity and search for correlated changes to the persistent X-ray emission of the source. The T 90 durations of the bursts range between 18 and 140 ms, comparable to other magnetar burst durations, while the energy released in each burst ranges between (0.8-25) × 1038 erg, which is on the low side of soft gamma repeater bursts. We find that the bursting activity did not have a significant effect on the persistent flux level of the source. We argue that the mechanism leading to this sporadic burst activity in 1E 1841-045 might not involve large-scale restructuring (either crustal or magnetospheric) as seen in other magnetar sources.

  11. The -14010*C variant associated with lactase persistence is located between an Oct-1 and HNF1α binding site and increases lactase promoter activity.

    PubMed

    Jensen, Tine G K; Liebert, Anke; Lewinsky, Rikke; Swallow, Dallas M; Olsen, Jørgen; Troelsen, Jesper T

    2011-10-01

    In most people worldwide intestinal lactase expression declines in childhood. In many others, particularly in Europeans, lactase expression persists into adult life. The lactase persistence phenotype is in Europe associated with the -13910*T single nucleotide variant located 13,910 bp upstream the lactase gene in an enhancer region that affects lactase promoter activity. This variant falls in an Oct-1 binding site and shows greater Oct-1 binding than the ancestral variant and increases enhancer activity. Several other variants have been identified very close to the -13910 position, which are associated with lactase persistence in the Middle East and Africa. One of them, the -14010*C, is associated with lactase persistence in Africa. Here we show by deletion analysis that the -14010 position is located in a 144 bp region that reduces the enhancer activity. In transfections the -14010*C allele shows a stronger enhancer effect than the ancestral -4010*G allele. Binding sites for Oct-1 and HNF1α surrounding the -14010 position were identified by gel shift assays, which indicated that -14010*C has greater binding affinity to Oct-1 than -14010*G.

  12. Activation of α7 nicotinic acetylcholine receptors persistently enhances hippocampal synaptic transmission and prevents Aß-mediated inhibition of LTP in the rat hippocampus.

    PubMed

    Ondrejcak, Tomas; Wang, Qinwen; Kew, James N C; Virley, David J; Upton, Neil; Anwyl, Roger; Rowan, Michael J

    2012-02-29

    Nicotinic acetylcholine receptors mediate fast cholinergic modulation of glutamatergic transmission and synaptic plasticity. Here we investigated the effects of subtype selective activation of the α7 nicotinic acetylcholine receptors on hippocampal transmission and the inhibition of synaptic long-term potentiation by the Alzheimer's disease associated amyloid ß-protein (Aß). The α7 nicotinic acetylcholine receptor agonist "compound A" ((R)-N-(1-azabicyclo[2.2.2]oct-3-yl)(5-(2-pyridyl))thiophene-2-carboxamide) induced a rapid-onset persistent enhancement of synaptic transmission in the dentate gyrus in vitro. Consistent with a requirement for activation of α7 nicotinic acetylcholine receptors, the type II α7-selective positive allosteric modulator PheTQS ((3aR, 4S, 9bS)-4-(4-methylphenyl)-3a,4,5,9b-tetrahydro-3H-cyclopenta[c]quinoline-8-sulfonamide) potentiated, and the antagonist methyllycaconitine (MLA) prevented the persistent enhancement. Systemic injection of the agonist also induced a similar MLA-sensitive persistent enhancement of synaptic transmission in the CA1 area in vivo. Remarkably, although compound A did not affect control long-term potentiation (LTP) in vitro, it prevented the inhibition of LTP by Aß1-42 and this effect was inhibited by MLA. These findings strongly indicate that activation of α7 nicotinic acetylcholine receptors is sufficient to persistently enhance hippocampal synaptic transmission and to overcome the inhibition of LTP by Aß.

  13. Voluntary activation failure is detectable in some myositis patients with persisting quadriceps femoris weakness: an observational study

    PubMed Central

    Molloy, Catherine B; Al-Omar, Ahmed O; Edge, Kathryn T; Cooper, Robert G

    2006-01-01

    This cross-sectional, observational study was undertaken to examine whether voluntary activation failure could contribute to the persisting weakness observed in some patients with treated idiopathic inflammatory myositis. In 20 patients with myositis of more than six months' duration (5 males, 15 females; mean [± 1 SD] age 53 [11] years) and 102 normal subjects (44 males, 58 females; mean age 32 [8] years), isometric maximum voluntary contractions (MVCs) of the dominant quadriceps femoris (QF) were quantified. Absolute MVC results of normal subjects and patients were then normalised with respect to lean body mass (force per units of lean body mass), giving a result in Newtons per kilogram. Based on mass-normalised force data of normal subjects, patients were arbitrarily stratified into "weak" and "not weak" subgroups. During further MVC attempts, the "twitch interpolation" technique was used to assess whether the QF voluntary activation of patients was complete. This technique relies on the fact that, because muscle activation is incomplete during submaximal voluntary contractions, electrical stimulation of the muscle can induce force increments superimposed on the submaximal voluntary force being generated. No between-gender differences were seen in the mass-normalised MVC results of healthy subjects, so the gender-combined results of 6.6 (1.5) N/kg were used for patient stratification. No between-gender difference was found for mass-normalised MVCs in patients: males 5.4 (3.2) and females 3.0 (1.7) N/kg (p > 0.05). Mass-normalised MVCs of male patients were as great as those of normal subjects (p > 0.05), but mass-normalised MVCs of female patients were significantly smaller than those of the normal subjects (p < 0.001). Only one of the six "not weak" patients exhibited interpolated twitches during electrical stimulation, but six of the 14 "weak" patients did, the biggest twitches being seen in the weakest patient. That interpolated twitches can be induced in

  14. VANADL SULFATE INHIBITS NO PRODUCTION BY DIFFERENTIALLY REGULATING SERINE/THREONINE PHOSPHORYLATION OF ENOS

    EPA Science Inventory

    VANADYL SULFATE INHIBITS NO PRODUCTION BY DIFFERENTIALLY REGULATING SERINE/THREONINE PHOSPHORYLATION OF eNOS. Zhuowei Li, Jacqueline D. Carter, Lisa A. Dailey, Joleen Soukup, Yuh-Chin T. Huang. CEMALB, University of North Carolina and ORD, US EPA, Chapel Hill, North Carolina
    V...

  15. VANADYL SULFATE INHIBITS NO PRODUCTION BY DIFFERENTIALLY REGULATING SERINE/THREONINE PHOSPHORYLATION OF ENOS

    EPA Science Inventory

    VANADYL SULFATE INHIBITS NO PRODUCTION BY DIFFERENTIALLY REGULATING SERINE/THREONINE PHOSPHORYLATION OF eNOS.

    Zhuowei Li, Jacqueline D. Carter, Lisa A. Dailey, Joleen Soukup, Yuh-Chin T. Huang. CEMALB, University of North Carolina and NHEERL, US EPA, Chapel Hill, North Ca...

  16. ENOS-G894T polymorphism is a risk factor for essential hypertension in China.

    PubMed

    Men, Chen; Tang, Kangting; Lin, Gang; Li, Jian; Zhan, Yiyang

    2011-06-01

    Vascular endothelial cells produce nitric oxide (NO), which contributes to the regulation of blood pressure and regional blood flow. Polymorphisms of the endothelial nitric oxide synthase (eNOS) gene are associated with coronary artery disease; however, associations between polymorphism (G894T) of the eNOS gene and essential hypertension remain unclear. This study was designed to investigate the association between a eNOS-G894T polymorphism and essential hypertension (EH). A total of 190 Chinese EH patients (EH group) and 94 healthy participants (control group) were included in the study. eNOS-G894T was determined using multi-polymerase chain reaction and polymorphisms in eNOS-G894T were genotyped using gene chip technology. Patients carrying eNOS GT + TT genotypes had a higher risk of EH than those carrying the GG genotype (OR = 2.82, 95% CI: 1.05-7.60, P = 0.033). The EH group showed a significantly higher frequency of the T-allele compared with controls (OR = 3.48, 95% CI: 1.34-9.07; P = 0.007). eNOS-894T was found to be significantly associated with EH in the dominant genetic model. Thus, the study demonstrated a significant and independent association between a eNOS-G894T polymorphism and EH in the Chinese patients. The study also showed that eNOS-G894T polymorphism is a risk factor for EH in Chinese patients. PMID:21793305

  17. Endocrine activity of persistent organic pollutants accumulated in human silicone implants--Dosing in vitro assays by partitioning from silicone.

    PubMed

    Gilbert, Dorothea; Mayer, Philipp; Pedersen, Mikael; Vinggaard, Anne Marie

    2015-11-01

    Persistent organic pollutants (POPs) accumulated in human tissues may pose a risk for human health by interfering with the endocrine system. This study establishes a new link between actual human internal POP levels and the endocrine active dose in vitro, applying partitioning-controlled dosing from silicone to the H295R steroidogenesis assay: (1) Measured concentrations of POPs in silicone breast implants were taken from a recent study and silicone disks were loaded according to these measurements. (2) Silicone disks were transferred into H295R cell culture plates in order to control exposure of the adrenal cells by equilibrium partitioning. (3) Hormone production of the adrenal cells was measured as toxicity endpoint. 4-Nonylphenol was used for method development, and the new dosing method was compared to conventional solvent-dosing. The two dosing modes yielded similar dose-dependent hormonal responses of H295R cells. However, with the partitioning-controlled freely dissolved concentrations (Cfree) as dose metrics, dose-response curves were left-shifted by two orders of magnitude relative to spiked concentrations. Partitioning-controlled dosing of POPs resulted in up to 2-fold increases in progestagen and corticosteroid levels at Cfree of individual POPs in or below the femtomolar range. Silicone acted not only as source of the POPs but also as a sorption sink for lipophilic hormones, stimulating the cellular hormone production. Methodologically, the study showed that silicone can be used as reference partitioning phase to transfer in vivo exposure in humans (silicone implants) to in vitro assays (partition-controlled dosing). The main finding was that POPs at the levels at which they are found in humans can interfere with steroidogenesis in a human adrenocortical cell line. PMID:26264162

  18. New Findings in eNOS gene and Thalidomide Embryopathy Suggest pre-transcriptional effect variants as susceptibility factors.

    PubMed

    Kowalski, Thayne Woycinck; Fraga, Lucas Rosa; Tovo-Rodrigues, Luciana; Sanseverino, Maria Teresa Vieira; Hutz, Mara Helena; Schuler-Faccini, Lavínia; Vianna, Fernanda Sales Luiz

    2016-01-01

    Antiangiogenic properties of thalidomide have created an interest in the use of the drug in treatment of cancer. However, thalidomide is responsible for thalidomide embryopathy (TE). A lack of knowledge regarding the mechanisms of thalidomide teratogenesis acts as a barrier in the aim to synthesize a safer analogue of thalidomide. Recently, our group detected a higher frequency of alleles that impair the pro-angiogenic mechanisms of endothelial nitric oxide synthase (eNOS), coded by the NOS3 gene. In this study we evaluated variable number tandem repeats (VNTR) functional polymorphism in intron 4 of NOS3 in individuals with TE (38) and Brazilians without congenital anomalies (136). Haplotypes were estimated for this VNTR with previously analyzed polymorphisms, rs2070744 (-786C > T) and rs1799983 (894T > G), in promoter region and exon 7, respectively. Haplotypic distribution was different between the groups (p = 0.007). Alleles -786C (rs2070744) and 4b (VNTR), associated with decreased NOS3 expression, presented in higher frequency in TE individuals (p = 0.018; OR = 2.57; IC = 1.2-5.8). This association was not identified with polymorphism 894T > G (p = 0.079), which influences eNOS enzymatic activity. These results suggest variants in NOS3, with pre-transcriptional effects as susceptibility factors, influencing the risk TE development. This finding generates insight for a new approach to research that pursues a safer analogue. PMID:27004986

  19. New Findings in eNOS gene and Thalidomide Embryopathy Suggest pre-transcriptional effect variants as susceptibility factors

    PubMed Central

    Kowalski, Thayne Woycinck; Fraga, Lucas Rosa; Tovo-Rodrigues, Luciana; Sanseverino, Maria Teresa Vieira; Hutz, Mara Helena; Schuler-Faccini, Lavínia; Vianna, Fernanda Sales Luiz

    2016-01-01

    Antiangiogenic properties of thalidomide have created an interest in the use of the drug in treatment of cancer. However, thalidomide is responsible for thalidomide embryopathy (TE). A lack of knowledge regarding the mechanisms of thalidomide teratogenesis acts as a barrier in the aim to synthesize a safer analogue of thalidomide. Recently, our group detected a higher frequency of alleles that impair the pro-angiogenic mechanisms of endothelial nitric oxide synthase (eNOS), coded by the NOS3 gene. In this study we evaluated variable number tandem repeats (VNTR) functional polymorphism in intron 4 of NOS3 in individuals with TE (38) and Brazilians without congenital anomalies (136). Haplotypes were estimated for this VNTR with previously analyzed polymorphisms, rs2070744 (−786C > T) and rs1799983 (894T > G), in promoter region and exon 7, respectively. Haplotypic distribution was different between the groups (p = 0.007). Alleles −786C (rs2070744) and 4b (VNTR), associated with decreased NOS3 expression, presented in higher frequency in TE individuals (p = 0.018; OR = 2.57; IC = 1.2–5.8). This association was not identified with polymorphism 894T > G (p = 0.079), which influences eNOS enzymatic activity. These results suggest variants in NOS3, with pre-transcriptional effects as susceptibility factors, influencing the risk TE development. This finding generates insight for a new approach to research that pursues a safer analogue. PMID:27004986

  20. Ablation of eNOS does not promote adipose tissue inflammation.

    PubMed

    Jurrissen, Thomas J; Sheldon, Ryan D; Gastecki, Michelle L; Woodford, Makenzie L; Zidon, Terese M; Rector, R Scott; Vieira-Potter, Victoria J; Padilla, Jaume

    2016-04-15

    Adipose tissue (AT) inflammation is a hallmark characteristic of obesity and an important determinant of insulin resistance and cardiovascular disease; therefore, a better understanding of factors regulating AT inflammation is critical. It is well established that reduced vascular endothelial nitric oxide (NO) bioavailability promotes arterial inflammation; however, the role of NO in modulating inflammation in AT remains disputed. In the present study, 10-wk-old C57BL6 wild-type and endothelial nitric oxide synthase (eNOS) knockout male mice were randomized to either a control diet (10% kcal from fat) or a Western diet (44.9% kcal from fat, 17% sucrose, and 1% cholesterol) for 18 wk (n= 7 or 8/group). In wild-type mice, Western diet-induced obesity led to increased visceral white AT expression of inflammatory genes (e.g., MCP1, TNF-α, and CCL5 mRNAs) and markers of macrophage infiltration (e.g., CD68, ITGAM, EMR1, CD11C mRNAs, and Mac-2 protein), as well as reduced markers of mitochondrial content (e.g., OXPHOS complex I and IV protein). Unexpectedly, these effects of Western diet on visceral white AT were not accompanied by decreases in eNOS phosphorylation at Ser-1177 or increases in eNOS phosphorylation at Thr-495. Also counter to expectations, eNOS knockout mice, independent of the diet, were leaner and did not exhibit greater white or brown AT inflammation compared with wild-type mice. Collectively, these findings do not support the hypothesis that reduced NO production from eNOS contributes to obesity-related AT inflammation. PMID:26864812

  1. Persistent At-Level Thermal Hyperalgesia and Tactile Allodynia Accompany Chronic Neuronal and Astrocyte Activation in Superficial Dorsal Horn following Mouse Cervical Contusion Spinal Cord Injury

    PubMed Central

    Watson, Jaime L.; Hala, Tamara J.; Putatunda, Rajarshi; Sannie, Daniel; Lepore, Angelo C.

    2014-01-01

    In humans, sensory abnormalities, including neuropathic pain, often result from traumatic spinal cord injury (SCI). SCI can induce cellular changes in the CNS, termed central sensitization, that alter excitability of spinal cord neurons, including those in the dorsal horn involved in pain transmission. Persistently elevated levels of neuronal activity, glial activation, and glutamatergic transmission are thought to contribute to the hyperexcitability of these dorsal horn neurons, which can lead to maladaptive circuitry, aberrant pain processing and, ultimately, chronic neuropathic pain. Here we present a mouse model of SCI-induced neuropathic pain that exhibits a persistent pain phenotype accompanied by chronic neuronal hyperexcitability and glial activation in the spinal cord dorsal horn. We generated a unilateral cervical contusion injury at the C5 or C6 level of the adult mouse spinal cord. Following injury, an increase in the number of neurons expressing ΔFosB (a marker of chronic neuronal activation), persistent astrocyte activation and proliferation (as measured by GFAP and Ki67 expression), and a decrease in the expression of the astrocyte glutamate transporter GLT1 are observed in the ipsilateral superficial dorsal horn of cervical spinal cord. These changes have previously been associated with neuronal hyperexcitability and may contribute to altered pain transmission and chronic neuropathic pain. In our model, they are accompanied by robust at-level hyperaglesia in the ipsilateral forepaw and allodynia in both forepaws that are evident within two weeks following injury and persist for at least six weeks. Furthermore, the pain phenotype occurs in the absence of alterations in forelimb grip strength, suggesting that it represents sensory and not motor abnormalities. Given the importance of transgenic mouse technology, this clinically-relevant model provides a resource that can be used to study the molecular mechanisms contributing to neuropathic pain

  2. Intensive Instruction Affects Brain Magnetic Activity Associated with Oral Word Reading in Children with Persistent Reading Disabilities

    ERIC Educational Resources Information Center

    Simos, Panagiotis G.; Fletcher, Jack M.; Sarkari, Shirin; Billingsley-Marshall, Rebecca; Denton, Carolyn A.; Papanicolaou, Andrew C.

    2007-01-01

    Fifteen children ages 7 to 9 years who had persistent reading difficulties despite adequate instruction were provided with intensive tutorial interventions. The interventions targeted deficient phonological processing and decoding skills for 8 weeks (2 hours per day) followed by an 8-week, 1-hour-per-day intervention that focused on the…

  3. Persistent Electrical Activity in Primary Nociceptors after Spinal Cord Injury Is Maintained by Scaffolded Adenylyl Cyclase and Protein Kinase A and Is Associated with Altered Adenylyl Cyclase Regulation

    PubMed Central

    Bavencoffe, Alexis; Li, Yong; Wu, Zizhen; Yang, Qing; Herrera, Juan; Kennedy, Eileen J.

    2016-01-01

    Little is known about intracellular signaling mechanisms that persistently excite neurons in pain pathways. Persistent spontaneous activity (SA) generated in the cell bodies of primary nociceptors within dorsal root ganglia (DRG) has been found to make major contributions to chronic pain in a rat model of spinal cord injury (SCI) (Bedi et al., 2010; Yang et al., 2014). The occurrence of SCI-induced SA in a large fraction of DRG neurons and the persistence of this SA long after dissociation of the neurons provide an opportunity to define intrinsic cell signaling mechanisms that chronically drive SA in pain pathways. The present study demonstrates that SCI-induced SA requires continuing activity of adenylyl cyclase (AC) and cAMP-dependent protein kinase (PKA), as well as a scaffolded complex containing AC5/6, A-kinase anchoring protein 150 (AKAP150), and PKA. SCI caused a small but significant increase in the expression of AKAP150 but not other AKAPs. DRG membranes isolated from SCI animals revealed a novel alteration in the regulation of AC. AC activity stimulated by Ca2+-calmodulin increased, while the inhibition of AC activity by Gαi showed an unexpected and dramatic decrease after SCI. Localized enhancement of the activity of AC within scaffolded complexes containing PKA is likely to contribute to chronic pathophysiological consequences of SCI, including pain, that are promoted by persistent hyperactivity in DRG neurons. SIGNIFICANCE STATEMENT Chronic neuropathic pain is a major clinical problem with poorly understood mechanisms and inadequate treatments. Recent findings indicate that chronic pain in a rat SCI model depends upon hyperactivity in dorsal root ganglia (DRG) neurons. Although cAMP signaling is involved in many forms of neural plasticity, including hypersensitivity of nociceptors in the presence of inflammatory mediators, our finding that continuing cAMP-PKA signaling is required for persistent SA months after SCI and long after isolation of

  4. Coinfection with Human Herpesvirus 8 Is Associated with Persistent Inflammation and Immune Activation in Virologically Suppressed HIV-Infected Patients

    PubMed Central

    Masiá, Mar; Robledano, Catalina; Ortiz de la Tabla, Victoria; Antequera, Pedro; Lumbreras, Blanca; Hernández, Ildefonso; Gutiérrez, Félix

    2014-01-01

    Objectives Infection with co-pathogens is one of the postulated factors contributing to persistent inflammation and non-AIDS events in virologically-suppressed HIV-infected patients. We aimed to investigate the relationship of human herpesvirus-8 (HHV-8), a vasculotropic virus implicated in the pathogenesis of Kaposi's sarcoma, with inflammation and subclinical atherosclerosis in HIV-infected patients. Methods Prospective study including virologically suppressed HIV-infected patients. Several blood biomarkers (highly-sensitive C-reactive protein [hsCRP], tumour necrosis factor-α, interleukin-6, monocyte chemoattractant protein-1, vascular cell adhesion molecule-1, intercellular cell adhesion molecule-1, malondialdehyde, plasminogen activator inhibitor [PAI-1], D-dimer, sCD14, sCD163, CD4/CD38/HLA-DR, and CD8/CD38/HLA-DR), serological tests for HHV-8 and the majority of herpesviruses, carotid intima-media thickness, and endothelial function through flow-mediated dilatation of the brachial artery were measured. Results A total of 136 patients were included, 34.6% of them infected with HHV-8. HHV-8-infected patients were more frequently co-infected with herpes simplex virus type 2 (HSV-2) (P<0.001), and less frequently with hepatitis C virus (HCV) (P = 0.045), and tended to be older (P = 0.086). HHV-8-infected patients had higher levels of hsCRP (median [interquartile range], 3.63 [1.32–7.54] vs 2.08 [0.89–4.11] mg/L, P = 0.009), CD4/CD38/HLA-DR (7.67% [4.10–11.86]% vs 3.86% [2.51–7.42]%, P = 0.035) and CD8/CD38/HLA-DR (8.02% [4.98–14.09]% vs 5.02% [3.66–6.96]%, P = 0.018). After adjustment for the traditional cardiovascular risk factors, HCV and HSV-2 infection, the associations remained significant: adjusted difference between HHV-8 positive and negative patients (95% confidence interval) for hsCRP, 74.19% (16.65–160.13)%; for CD4/CD38/HLA-DR, 89.65% (14.34–214.87)%; and for CD8/CD38/HLA-DR, 58.41% (12.30–123.22)%. Flow

  5. Age-Dependent Differences in the Strength and Persistence of Psychostimulant-Induced Conditioned Activity in Rats: Effects of a Single Environment-Cocaine Pairing

    PubMed Central

    McDougall, Sanders A.; Pipkin, Joseph A.; Der-Ghazarian, Taleen; Cortez, Anthony M.; Gutierrez, Arnold; Lee, Ryan J.; Carbajal, Sandra; Mohd-Yusof, Alena

    2014-01-01

    The purpose of the present study was to determine the strength and persistence of cocaine-induced conditioned activity in young and adult rats. A one-trial protocol has proven useful for studying the ontogeny of psychostimulant-induced behavioral sensitization; therefore, a similar procedure was used to examine conditioned activity. On postnatal day (PD) 19 or PD 80, rats were injected with saline or cocaine in either a novel test chamber or the home cage. After various drug abstinence intervals (1–21 days), rats were injected with saline and returned to the test chamber, where conditioned activity was assessed. In a separate experiment, we examined whether cocaine-induced conditioned activity was a consequence of Pavlovian conditioning or a failure to habituate to the test environment. The results showed that adult rats exhibited strong one-trial conditioned activity that persisted for at least 21 days, whereas young rats did not show a conditioned locomotor response. The conditioned activity exhibited by adult rats did not result from a failure to habituate to the cocaine-paired environment. These results indicate that cocaine-paired contextual stimuli differentially affect behavior depending on age of the animal. The data provided by adult rats have potential translational relevance for humans because a single environment-drug pairing caused long-term alterations in behavior. PMID:25171082

  6. An artificial compression method for ENO schemes: The slope modification method

    NASA Technical Reports Server (NTRS)

    Yang, Huanan

    1988-01-01

    A simple and effective method of artificial compression is introduced. This method is based on a modification of the slopes of the ENO (essentially nonoscillatory) reconstruction and, with the help of suitable chosen parameters, greatly improves the resolution of the contact discontinuities. Numerical examples are provided to test the performance of the method and to give some suggestions as to the choice of the parameters.

  7. Diesel exhaust exposure enhances venoconstriction via uncoupling of eNOS

    SciTech Connect

    Knuckles, Travis L.; Lund, Amie K.; Lucas, Selita N.; Campen, Matthew J.

    2008-08-01

    Environmental air pollution is associated with adverse cardiovascular events, including increased hospital admissions due to heart failure and myocardial infarction. The exact mechanism(s) by which air pollution affects the heart and vasculature is currently unknown. Recent studies have found that exposure to air pollution enhances arterial vasoconstriction in humans and animal models. Work in our laboratory has shown that diesel emissions (DE) enhance vasoconstriction of mouse coronary arteries. Thus, we hypothesized that DE could enhance vasoconstriction in arteries and veins through uncoupling of endothelial nitric oxide synthase (eNOS). To test this hypothesis, we first bubbled DE through a physiological saline solution and exposed isolated mesenteric veins. Second, we exposed animals, whole body, to DE at 350 {mu}g/m{sup 3} for 4 h, after which mesenteric arteries and veins were isolated. Results from these experiments show that saline bubbled with DE as well as inhaled DE enhances vasoconstriction in veins but not arteries. Exposure to several representative volatile organic compounds found in the DE-exposed saline did not enhance arterial constriction. L-nitro-arginine-methyl-ester (L-NAME), an eNOS inhibitor, normalized the control vessels to the DE-exposed vessels implicating an uncoupling of eNOS as a mechanism for enhanced vasoconstriction. The principal conclusions of this research are 1) veins exhibit endothelial dysfunction following in vivo and ex vivo exposures to DE, 2) veins appear to be more sensitive to DE effects than arteries, and 3) DE components most likely induce endothelial dysfunction through the uncoupling of eNOS.

  8. Some Aspects of Essentially Nonoscillatory (ENO) Formulations for the Euler Equations, Part 3

    NASA Technical Reports Server (NTRS)

    Chakravarthy, Sukumar R.

    1990-01-01

    An essentially nonoscillatory (ENO) formulation is described for hyperbolic systems of conservation laws. ENO approaches are based on smart interpolation to avoid spurious numerical oscillations. ENO schemes are a superset of Total Variation Diminishing (TVD) schemes. In the recent past, TVD formulations were used to construct shock capturing finite difference methods. At extremum points of the solution, TVD schemes automatically reduce to being first-order accurate discretizations locally, while away from extrema they can be constructed to be of higher order accuracy. The new framework helps construct essentially non-oscillatory finite difference methods without recourse to local reductions of accuracy to first order. Thus arbitrarily high orders of accuracy can be obtained. The basic general ideas of the new approach can be specialized in several ways and one specific implementation is described based on: (1) the integral form of the conservation laws; (2) reconstruction based on the primitive functions; (3) extension to multiple dimensions in a tensor product fashion; and (4) Runge-Kutta time integration. The resulting method is fourth-order accurate in time and space and is applicable to uniform Cartesian grids. The construction of such schemes for scalar equations and systems in one and two space dimensions is described along with several examples which illustrate interesting aspects of the new approach.

  9. Buckling Reduces eNOS Production and Stimulates Extracellular Matrix Remodeling in Arteries in Organ Culture.

    PubMed

    Xiao, Yangming; Liu, Qin; Han, Hai-Chao

    2016-09-01

    Artery buckling alters the fluid shear stress and wall stress in the artery but its temporal effect on vascular wall remodeling is poorly understood. The purpose of this study was to investigate the early effect of artery buckling on endothelial nitric oxide synthase (eNOS) expression and extracellular matrix remodeling. Bilateral porcine carotid arteries were maintained in an ex vivo organ culture system with and without buckling while under the same physiological pressure and flow rate for 3-7 days. Matrix metalloproteinase-2 (MMP-2), MMP-9, fibronectin, elastin, collagen I, III and IV, tissue inhibitor of metalloproteinase-2 (TIMP-2), and eNOS were determined using Western blotting and immunohistochemistry. Our results showed that MMP-2 expression level was significantly higher in buckled arteries than in the controls and higher at the inner curve than at the outer curve of buckled arteries, while collagen IV content showed an opposite trend, suggesting that artery buckling increased MMP-2 expression and collagen IV degradation in a site-specific fashion. However, no differences for MMP-9, fibronectin, elastin, collagen I, III, and TIMP-2 were observed among the outer and inner curve sides of buckled arteries and straight controls. Additionally, eNOS expression was significantly decreased in buckled arteries. These results suggest that artery buckling triggers uneven wall remodeling that could lead to development of tortuous arteries. PMID:26913855

  10. Correlation between pulmonary gas exchange and basal and nitroglycerin (GTN)-induced exhaled nitric oxide (eNO) in patients undergoing cardiac surgery.

    PubMed

    Kövesi, Tamás; Szabo, Anita; Royston, David; Marczin, Nándor

    2005-12-01

    The relationship between eNO and events in the alveolar-capillary unit in acute lung injury remains to be established. Since endogenous eNO largely originates from the airway epithelium, but nitroglycerin (GTN)-induced eNO is due to microvascular/alveolar metabolism, we have proposed to use basal and GTN-induced eNO as metabolic markers of the airway--and microvascular/alveolar function, respectively. The current work investigates the relationship between basal and GTN-induced eNO and oxygenation parameters (PaO(2)/FiO(2) ratio) in patients undergoing cardiac surgery utilising cardiopulmonary bypass (CPB). Breath by breath eNO measurements were made in 10 patients before, and 1 and 3 h after CPB either under basal conditions or following intravenous administration of GTN (1, 2 and 3 microg/kg). Basal eNO remained unchanged, whereas GTN-induced eNO was reduced following CPB. Also, there was a transient reduction in PaO(2)/FiO(2) ratio 1 h after CPB (32+/-4 vs. 44+/-3 kPa). A negative correlation was found between oxygenation and basal eNO by Pearson's correlation test and linear regression analysis suggesting that decreased oxygenation was associated with increased basal eNO. In contrast, a decrease in GTN-induced eNO positively correlated with reduced oxygenation index (R=0.533, p=0.002). These data suggest that differential relationships exist between basal and nitrovasodilator-induced eNO and oxygenation indices during subclinical lung injury in patients following CPB and that GTN-induced eNO evolution may reflect better microvascular events and injury.

  11. Computational and anti-tumor studies of 7a-Aza-B-homostigmast-5-eno [7a, 7-d] tetrazole-3β-yl chloride

    NASA Astrophysics Data System (ADS)

    Alam, Mahboob; Alam, Mohammad Jane; Nami, Shahab A. A.; Lee, Dong-Ung; Azam, Mohammad; Ahmad, Shabbir

    2016-03-01

    The present paper reports the detailed computational study including molecular docking of a biologically active steroidal tetrazole, 7a-Aza-B-homostigmast-5-eno [7a,7-d] tetrazole-3β-yl chloride. The molecular structure, IR and NMR (13C and 1H) spectra of the tetrazole were interpreted by comparing the experimental results with the theoretical, B3LYP/6-311G(d,p) calculations. The vibrational bands appearing in the FTIR are assigned with great accuracy using animated modes. Molecular properties like HOMO-LUMO analysis, chemical reactivity descriptors, MEP mapping, dipole moment and natural atomic charges have been presented at the same level of theory. The theoretical results are found in good correlation with the experimental data. Moreover, the Hirshfeld analysis was carried out to ascertain the secondary interactions and associated 2D fingerprint plots. The in vitro anti-tumor activity of 7a-Aza-B-homostigmast-5-eno [7a,7-d] tetrazole-3β-yl chloride has also been carried out against five human tumor cell lines. Doxorubicin is used as a standard drug for the in vitro anti-tumor screening.

  12. Computational and anti-tumor studies of 7a-Aza-B-homostigmast-5-eno [7a, 7-d] tetrazole-3β-yl chloride

    NASA Astrophysics Data System (ADS)

    Alam, Mahboob; Alam, Mohammad Jane; Nami, Shahab A. A.; Lee, Dong-Ung; Azam, Mohammad; Ahmad, Shabbir

    2016-03-01

    The present paper reports the detailed computational study including molecular docking of a biologically active steroidal tetrazole, 7a-Aza-B-homostigmast-5-eno [7a,7-d] tetrazole-3β-yl chloride. The molecular structure, IR and NMR (13C and 1H) spectra of the tetrazole were interpreted by comparing the experimental results with the theoretical, B3LYP/6-311G(d,p) calculations. The vibrational bands appearing in the FTIR are assigned with great accuracy using animated modes. Molecular properties like HOMO-LUMO analysis, chemical reactivity descriptors, MEP mapping, dipole moment and natural atomic charges have been presented at the same level of theory. The theoretical results are found in good correlation with the experimental data. Moreover, the Hirshfeld analysis was carried out to ascertain the secondary interactions and associated 2D fingerprint plots. The in vitro anti-tumor activity of 7a-Aza-B-homostigmast-5-eno [7a,7-d] tetrazole-3β-yl chloride has also been carried out against five human tumor cell lines. Doxorubicin is used as a standard drug for the in vitro anti-tumor screening.

  13. Vasoinhibins prevent retinal vasopermeability associated with diabetic retinopathy in rats via protein phosphatase 2A–dependent eNOS inactivation

    PubMed Central

    García, Celina; Aranda, Jorge; Arnold, Edith; Thébault, Stéphanie; Macotela, Yazmín; López-Casillas, Fernando; Mendoza, Valentín; Quiroz-Mercado, Hugo; Hernández-Montiel, Hebert Luis; Lin, Sue-Hwa; de la Escalera, Gonzalo Martínez; Clapp, Carmen

    2008-01-01

    Increased retinal vasopermeability contributes to diabetic retinopathy, the leading cause of blindness in working-age adults. Despite clinical progress, effective therapy remains a major need. Vasoinhibins, a family of peptides derived from the protein hormone prolactin (and inclusive of the 16-kDa fragment of prolactin), antagonize the proangiogenic effects of VEGF, a primary mediator of retinal vasopermeability. Here, we demonstrate what we believe to be a novel function of vasoinhibins as inhibitors of the increased retinal vasopermeability associated with diabetic retinopathy. Vasoinhibins inhibited VEGF-induced vasopermeability in bovine aortic and rat retinal capillary endothelial cells in vitro. In vivo, vasoinhibins blocked retinal vasopermeability in diabetic rats and in response to intravitreous injection of VEGF or of vitreous from patients with diabetic retinopathy. Inhibition by vasoinhibins was similar to that achieved following immunodepletion of VEGF from human diabetic retinopathy vitreous or blockage of NO synthesis, suggesting that vasoinhibins inhibit VEGF-induced NOS activation. We further showed that vasoinhibins activate protein phosphatase 2A (PP2A), leading to eNOS dephosphorylation at Ser1179 and, thereby, eNOS inactivation. Moreover, intravitreous injection of okadaic acid, a PP2A inhibitor, blocked the vasoinhibin effect on endothelial cell permeability and retinal vasopermeability. These results suggest that vasoinhibins have the potential to be developed as new therapeutic agents to control the excessive retinal vasopermeability observed in diabetic retinopathy and other vasoproliferative retinopathies. PMID:18497878

  14. Persistent Supercooling of Reproductive Shoots Is Enabled by Structural Ice Barriers Being Active Despite an Intact Xylem Connection

    PubMed Central

    Pfaller, Kristian; Wagner, Johanna

    2016-01-01

    Extracellular ice nucleation usually occurs at mild subzero temperatures in most plants. For persistent supercooling of certain plant parts ice barriers are necessary to prevent the entry of ice from already frozen tissues. The reproductive shoot of Calluna vulgaris is able to supercool down to below -22°C throughout all developmental stages (shoot elongation, flowering, fruiting) despite an established xylem conductivity. After localization of the persistent ice barrier between the reproductive and vegetative shoot at the base of the pedicel by infrared differential thermal analysis, the currently unknown structural features of the ice barrier tissue were anatomically analyzed on cross and longitudinal sections. The ice barrier tissue was recognized as a 250 μm long constriction zone at the base of the pedicel that lacked pith tissue and intercellular spaces. Most cell walls in this region were thickened and contained hydrophobic substances (lignin, suberin, and cutin). A few cell walls had what appeared to be thicker cellulose inclusions. In the ice barrier tissue, the area of the xylem was as much as 5.7 times smaller than in vegetative shoots and consisted of tracheids only. The mean number of conducting units in the xylem per cross section was reduced to 3.5% of that in vegetative shoots. Diameter of conducting units and tracheid length were 70% and 60% (respectively) of that in vegetative shoots. From vegetative shoots water transport into the ice barrier must pass pit membranes that are likely impermeable to ice. Pit apertures were about 1.9 μm x 0.7 μm, which was significantly smaller than in the vegetative shoot. The peculiar anatomical features of the xylem at the base of the pedicel suggest that the diameter of pores in pit membranes could be the critical constriction for ice propagation into the persistently supercooled reproductive shoots of C. vulgaris. PMID:27632365

  15. Persistent Supercooling of Reproductive Shoots Is Enabled by Structural Ice Barriers Being Active Despite an Intact Xylem Connection.

    PubMed

    Kuprian, Edith; Tuong, Tan D; Pfaller, Kristian; Wagner, Johanna; Livingston, David P; Neuner, Gilbert

    2016-01-01

    Extracellular ice nucleation usually occurs at mild subzero temperatures in most plants. For persistent supercooling of certain plant parts ice barriers are necessary to prevent the entry of ice from already frozen tissues. The reproductive shoot of Calluna vulgaris is able to supercool down to below -22°C throughout all developmental stages (shoot elongation, flowering, fruiting) despite an established xylem conductivity. After localization of the persistent ice barrier between the reproductive and vegetative shoot at the base of the pedicel by infrared differential thermal analysis, the currently unknown structural features of the ice barrier tissue were anatomically analyzed on cross and longitudinal sections. The ice barrier tissue was recognized as a 250 μm long constriction zone at the base of the pedicel that lacked pith tissue and intercellular spaces. Most cell walls in this region were thickened and contained hydrophobic substances (lignin, suberin, and cutin). A few cell walls had what appeared to be thicker cellulose inclusions. In the ice barrier tissue, the area of the xylem was as much as 5.7 times smaller than in vegetative shoots and consisted of tracheids only. The mean number of conducting units in the xylem per cross section was reduced to 3.5% of that in vegetative shoots. Diameter of conducting units and tracheid length were 70% and 60% (respectively) of that in vegetative shoots. From vegetative shoots water transport into the ice barrier must pass pit membranes that are likely impermeable to ice. Pit apertures were about 1.9 μm x 0.7 μm, which was significantly smaller than in the vegetative shoot. The peculiar anatomical features of the xylem at the base of the pedicel suggest that the diameter of pores in pit membranes could be the critical constriction for ice propagation into the persistently supercooled reproductive shoots of C. vulgaris.

  16. Persistent Supercooling of Reproductive Shoots Is Enabled by Structural Ice Barriers Being Active Despite an Intact Xylem Connection.

    PubMed

    Kuprian, Edith; Tuong, Tan D; Pfaller, Kristian; Wagner, Johanna; Livingston, David P; Neuner, Gilbert

    2016-01-01

    Extracellular ice nucleation usually occurs at mild subzero temperatures in most plants. For persistent supercooling of certain plant parts ice barriers are necessary to prevent the entry of ice from already frozen tissues. The reproductive shoot of Calluna vulgaris is able to supercool down to below -22°C throughout all developmental stages (shoot elongation, flowering, fruiting) despite an established xylem conductivity. After localization of the persistent ice barrier between the reproductive and vegetative shoot at the base of the pedicel by infrared differential thermal analysis, the currently unknown structural features of the ice barrier tissue were anatomically analyzed on cross and longitudinal sections. The ice barrier tissue was recognized as a 250 μm long constriction zone at the base of the pedicel that lacked pith tissue and intercellular spaces. Most cell walls in this region were thickened and contained hydrophobic substances (lignin, suberin, and cutin). A few cell walls had what appeared to be thicker cellulose inclusions. In the ice barrier tissue, the area of the xylem was as much as 5.7 times smaller than in vegetative shoots and consisted of tracheids only. The mean number of conducting units in the xylem per cross section was reduced to 3.5% of that in vegetative shoots. Diameter of conducting units and tracheid length were 70% and 60% (respectively) of that in vegetative shoots. From vegetative shoots water transport into the ice barrier must pass pit membranes that are likely impermeable to ice. Pit apertures were about 1.9 μm x 0.7 μm, which was significantly smaller than in the vegetative shoot. The peculiar anatomical features of the xylem at the base of the pedicel suggest that the diameter of pores in pit membranes could be the critical constriction for ice propagation into the persistently supercooled reproductive shoots of C. vulgaris. PMID:27632365

  17. Activity of creatinol O-phosphate on persistent ventricular premature beats in ischemic heart disease. Double blind clinical trial.

    PubMed

    Di Maio, F; Neri, A; Soccorsi, P; Sciacca, A

    1979-01-01

    In a double-blind investigation N-methyl-N-(beta-hydroxyethyl) guanidine O-phosphate (creatinol O-phosphate, COP) was checked versus a reference substance (solvent of COP) on volunteers affected by ischemic heart disease with persistent ventricular premature beats (VPB). COP was able to reduce VPB by 50--100% in 85% of the volunteers treated with this drug. This fact and the virtual absence of side-effects of COP lead the authors to the conclusion that COP merits more extensive investigations in this field in view of its clinical employment alone or in association with specific antiarrhythmic agents.

  18. Cigarette smoking leads to persistent and dose-dependent alterations of brain activity and connectivity in anterior insula and anterior cingulate.

    PubMed

    Zanchi, Davide; Brody, Arthur L; Montandon, Marie-Louise; Kopel, Rotem; Emmert, Kirsten; Preti, Maria Giulia; Van De Ville, Dimitri; Haller, Sven

    2015-11-01

    Although many smokers try to quit smoking, only about 20-25 percent will achieve abstinence despite 6 months or more of gold-standard treatment. This low success rate suggests long-term changes in the brain related to smoking, which remain poorly understood. We compared ex-smokers to both active smokers and non-smokers using functional magnetic resonance imaging (fMRI) to explore persistent modifications in brain activity and network organization. This prospective and consecutive study includes 18 non-smokers (29.5 ± 6.7 years of age, 11 women), 14 smokers (≥10 cigarettes a day >2 years of smoking, 29.3 ± 6.0 years of age, 10 women) and 14 ex-smokers (>1 year of quitting 30.5 ± 5.7 years of age, 10 women). Participants underwent a block-design fMRI study contrasting smoking cue with control (neutral cue) videos. Data analyses included task-related general linear model, seed-based functional connectivity, voxel-based morphometry (VBM) of gray matter and tract-based spatial statistics (TBSS) of white matter. Smoking cue videos versus control videos activated the right anterior insula in ex-smokers compared with smokers, an effect correlating with cumulative nicotine intake (pack-years). Moreover, ex-smokers had a persistent decrease in functional connectivity between right anterior insula and anterior cingulate cortex (ACC) compared with control participants, but similar to active smokers. Potentially confounding alterations in gray or white matter were excluded in VBM and TBSS analyses. In summary, ex-smokers with long-term nicotine abstinence have persistent and dose-dependent brain network changes notably in the right anterior insula and its connection to the ACC.

  19. West Nile Virus Activity in a Winter Roost of American Crows (Corvus brachyrhynchos): Is Bird-To-Bird Transmission Important in Persistence and Amplification?

    PubMed Central

    Hinton, M. G.; Reisen, W. K.; Wheeler, S. S.; Townsend, A. K.

    2015-01-01

    Since its emergence in North America, West Nile virus (WNV) has had a large impact on equines, humans, and wild bird communities, yet gaps remain in our understanding of how the virus persists at temperate latitudes when winter temperatures preclude virus replication and host-seeking activity by mosquito vectors. Bird-to-bird transmission at large communal American Crow roosts could provide one mechanism for WNV persistence. Herein, we describe seasonal patterns of crow and Culex mosquito abundance, WNV infection rates, and the prevalence of WNV-positive fecal samples at a winter crow roost to test the hypothesis that bird-to-bird transmission allows WNV to persist at winter crow roosts. Samples were collected from large winter crow roosts in the Sacramento Valley of California from January 2013 until August 2014, encompassing two overwintering roost periods. West Nile virus RNA was detected in local crow carcasses in both summer [13/18 (72% WNV positive)] and winter [18/44 (41% WNV positive)] 2013–2014. Winter infections were unlikely to have arisen by recent bites from infected mosquitoes because Culex host-seeking activity was very low in winter and all Culex mosquitoes collected during winter months tested negative for WNV. Opportunities existed for fecal-oral transfer at the overwintering roost: most carcasses that tested positive for WNV had detectable viral RNA in both kidney and cloacal swabs, suggesting that infected crows were shedding virus in their feces, and >50% of crows at the roost were stained with feces by mid-winter. Moreover, 2.3% of fecal samples collected in late summer, when mosquitoes were active, tested positive for WNV RNA. Nevertheless, none of the 1,119 feces collected from three roosts over two winters contained detectable WNV RNA. This study provided evidence of WNV infection in overwintering American crows without mosquito vector activity, but did not elucidate a mechanism of WNV transmission during winter. PMID:26335475

  20. West Nile Virus Activity in a Winter Roost of American Crows (Corvus brachyrhynchos): Is Bird-To-Bird Transmission Important in Persistence and Amplification?

    PubMed

    Hinton, M G; Reisen, W K; Wheeler, S S; Townsend, A K

    2015-07-01

    Since its emergence in North America, West Nile virus (WNV) has had a large impact on equines, humans, and wild bird communities, yet gaps remain in our understanding of how the virus persists at temperate latitudes when winter temperatures preclude virus replication and host-seeking activity by mosquito vectors. Bird-to-bird transmission at large communal American Crow roosts could provide one mechanism for WNV persistence. Herein, we describe seasonal patterns of crow and Culex mosquito abundance, WNV infection rates, and the prevalence of WNV-positive fecal samples at a winter crow roost to test the hypothesis that bird-to-bird transmission allows WNV to persist at winter crow roosts. Samples were collected from large winter crow roosts in the Sacramento Valley of California from January 2013 until August 2014, encompassing two overwintering roost periods. West Nile virus RNA was detected in local crow carcasses in both summer [13/18 (72% WNV positive)] and winter [18/44 (41% WNV positive)] 2013-2014. Winter infections were unlikely to have arisen by recent bites from infected mosquitoes because Culex host-seeking activity was very low in winter and all Culex mosquitoes collected during winter months tested negative for WNV. Opportunities existed for fecal-oral transfer at the overwintering roost: most carcasses that tested positive for WNV had detectable viral RNA in both kidney and cloacal swabs, suggesting that infected crows were shedding virus in their feces, and >50% of crows at the roost were stained with feces by mid-winter. Moreover, 2.3% of fecal samples collected in late summer, when mosquitoes were active, tested positive for WNV RNA. Nevertheless, none of the 1,119 feces collected from three roosts over two winters contained detectable WNV RNA. This study provided evidence of WNV infection in overwintering American crows without mosquito vector activity, but did not elucidate a mechanism of WNV transmission during winter.

  1. A novel multiplex PCR-RFLP method for simultaneous detection of the MTHFR 677 C > T, eNOS +894 G > T and - eNOS -786 T > C variants among Malaysian Malays

    PubMed Central

    2012-01-01

    Background Hyperhomocysteinemia as a consequence of the MTHFR 677 C > T variant is associated with cardiovascular disease and stroke. Another factor that can potentially contribute to these disorders is a depleted nitric oxide level, which can be due to the presence of eNOS +894 G > T and eNOS −786 T > C variants that make an individual more susceptible to endothelial dysfunction. A number of genotyping methods have been developed to investigate these variants. However, simultaneous detection methods using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis are still lacking. In this study, a novel multiplex PCR-RFLP method for the simultaneous detection of MTHFR 677 C > T and eNOS +894 G > T and eNOS −786 T > C variants was developed. A total of 114 healthy Malay subjects were recruited. The MTHFR 677 C > T and eNOS +894 G > T and eNOS −786 T > C variants were genotyped using the novel multiplex PCR-RFLP and confirmed by DNA sequencing as well as snpBLAST. Allele frequencies of MTHFR 677 C > T and eNOS +894 G > T and eNOS −786 T > C were calculated using the Hardy Weinberg equation. Methods The 114 healthy volunteers were recruited for this study, and their DNA was extracted. Primer pair was designed using Primer 3 Software version 0.4.0 and validated against the BLAST database. The primer specificity, functionality and annealing temperature were tested using uniplex PCR methods that were later combined into a single multiplex PCR. Restriction Fragment Length Polymorphism (RFLP) was performed in three separate tubes followed by agarose gel electrophoresis. PCR product residual was purified and sent for DNA sequencing. Results The allele frequencies for MTHFR 677 C > T were 0.89 (C allele) and 0.11 (T allele); for eNOS +894 G > T, the allele frequencies were 0.58 (G allele) and 0.43 (T allele); and for eNOS −786 T > C, the allele frequencies were 0.87 (T allele

  2. Persistent nicotine treatment potentiates amplification of the dihydrofolate reductase gene in rat lung epithelial cells as a consequence of Ras activation.

    PubMed

    Guo, Jinjin; Chu, Michelle; Abbeyquaye, Tetteh; Chen, Chang-Yan

    2005-08-26

    Although nicotine has been suggested to promote lung carcinogenesis, the mechanism of its action in this process remains unknown. The present investigation demonstrates that the treatment of rat lung epithelial cells with nicotine for various periods differentially mobilizes multiple intracellular pathways. Protein kinase C and phosphoinositide 3-OH-kinase are transiently activated after the treatment. Also, Ras and its downstream effector ERK1/2 are activated after long term exposure to nicotine. The activation of Ras by nicotine treatment is responsible for the subsequent perturbation of the methotrexate (MTX)-mediated G1 cell cycle restriction as well as an increase in production of reactive oxygen species. When p53 expression is suppressed by introducing E6, persistent exposure to nicotine enables dihydrofolate reductase gene amplification in the presence of methotrexate (MTX) and the formation of the MTX-resistant colonies. Altering the activity of phosphoinositide 3-OH-kinase has no effect on dihydrofolate reductase amplification. However, the suppression of protein kinase C dramatically affects the colony formation in soft agar. Thus, our data suggest that persistent exposure to nicotine perturbs the G1 checkpoint and causes DNA damage through the increase of the production of reactive oxygen species. However, a third element rendered by loss of p53 is required for the initiation of the process of gene amplification. Under p53-deficient conditions, the establishment of a full oncogenic transformation, in response to long term nicotine exposure, is achieved through the cooperation of multiple signaling pathways. PMID:15983034

  3. Metabolic aspects of bacterial persisters

    PubMed Central

    Prax, Marcel; Bertram, Ralph

    2014-01-01

    Persister cells form a multi-drug tolerant subpopulation within an isogenic culture of bacteria that are genetically susceptible to antibiotics. Studies with different Gram negative and Gram positive bacteria have identified a large number of genes associated with the persister state. In contrast, the revelation of persister metabolism has only been addressed recently. We here summarize metabolic aspects of persisters, which includes an overview about the bifunctional role of selected carbohydrates as both triggers for the exit from the drug tolerant state and metabolites which persisters feed on. Also alarmones as indicators for starvation have been shown to influence persister levels via different signaling cascades involving the activation of toxin-antitoxin systems and other regulatory factors. Finally, recent data obtained by 13C-isotopolog profiling demonstrated an active amino acid anabolism in Staphylococcus aureus cultures challenged with high drug concentrations. Understanding the metabolism of persister cells poses challenges but also paves the way for the development of anti-persister compounds. PMID:25374846

  4. GTPase-deficient G alpha 16 and G alpha q induce PC12 cell differentiation and persistent activation of cJun NH2-terminal kinases.

    PubMed Central

    Heasley, L E; Storey, B; Fanger, G R; Butterfield, L; Zamarripa, J; Blumberg, D; Maue, R A

    1996-01-01

    Persistent stimulation of specific protein kinase pathways has been proposed as a key feature of receptor tyrosine kinases and intracellular oncoproteins that signal neuronal differentiation of rat pheochromocytoma (PC12) cells. Among the protein serine/threonine kinases identified to date, the p42/44 mitogen-activated protein (MAP) kinases have been highlighted for their potential role in signalling PC12 cell differentiation. We report here that retrovirus-mediated expression of GTPase-deficient, constitutively active forms of the heterotrimeric Gq family members, G alpha qQ209L and G alpha 16Q212L, in PC12 cells induces neuronal differentiation as indicated by neurite outgrowth and the increased expression of voltage-dependent sodium channels. Differentiation was not observed after cellular expression of GTPase-deficient forms of alpha i2 or alpha 0, indicating selectivity for the Gq family of G proteins. As predicted, overexpression of alpha qQ209L and alpha 16Q212L constitutively elevated basal phospholipase C activity approximately 10-fold in PC12 cells. Significantly, little or no p42/44 MAP kinase activity was detected in PC12 cells differentiated with alpha 16Q212L or alpha qQ209L, although these proteins were strongly activated following expression of constitutively active cRaf-1. Rather, a persistent threefold activation of the cJun NH2-terminal kinases (JNKs) was observed in PC12 cells expressing alpha qQ209L and alpha 16Q212L. This level of JNK activation was similar to that achieved with nerve growth factor, a strong inducer of PC12 cell differentiation. Supportive of a role for JNK activation in PC12 cell differentiation, retrovirus-mediated overexpression of cJun, a JNK target, in PC12 cells induced neurite outgrowth. The results define a p42/44 MAP kinase-independent mechanism for differentiation of PC12 cells and suggest that persistent activation of the JNK members of the proline-directed protein kinase family by GTPase-deficient G alpha q and G

  5. Decreased endothelial nitric oxide synthase expression and function contribute to impaired mitochondrial biogenesis and oxidative stress in fetal lambs with persistent pulmonary hypertension.

    PubMed

    Afolayan, Adeleye J; Eis, Annie; Alexander, Maxwell; Michalkiewicz, Teresa; Teng, Ru-Jeng; Lakshminrusimha, Satyan; Konduri, Girija G

    2016-01-01

    Impaired vasodilation in persistent pulmonary hypertension of the newborn (PPHN) is characterized by mitochondrial dysfunction. We investigated the hypothesis that a decreased endothelial nitric oxide synthase level leads to impaired mitochondrial biogenesis and function in a lamb model of PPHN induced by prenatal ductus arteriosus constriction. We ventilated PPHN lambs with 100% O2 alone or with inhaled nitric oxide (iNO). We treated pulmonary artery endothelial cells (PAECs) from normal and PPHN lambs with detaNONOate, an NO donor. We observed decreased mitochondrial (mt) DNA copy number, electron transport chain (ETC) complex subunit levels, and ATP levels in PAECs and lung tissue of PPHN fetal lambs at baseline compared with gestation matched controls. Phosphorylation of AMP-activated kinase (AMPK) and levels of peroxisome proliferator-activated receptor-γ coactivator 1-α (PGC-1α) and sirtuin-1, which facilitate mitochondrial biogenesis, were decreased in PPHN. Ventilation with 100% O2 was associated with larger decreases in ETC subunits in the lungs of PPHN lambs compared with unventilated PPHN lambs. iNO administration, which facilitated weaning of FiO2 , partly restored mtDNA copy number, ETC subunit levels, and ATP levels. DetaNONOate increased eNOS phosphorylation and its interaction with heat shock protein 90 (HSP90); increased levels of superoxide dismutase 2 (SOD2) mRNA, protein, and activity; and decreased the mitochondrial superoxide levels in PPHN-PAECs. Knockdown of eNOS decreased ETC protein levels in control PAECs. We conclude that ventilation with 100% O2 amplifies oxidative stress and mitochondrial dysfunction in PPHN, which are partly improved by iNO and weaning of oxygen. PMID:26519208

  6. Association between eNOS polymorphisms and risk of coronary artery disease in a Korean population: a meta-analysis.

    PubMed

    Sung, J H; Lee, B E; Kim, J O; Jeon, Y J; Kim, S H; Lim, S W; Moon, J Y; Cha, D H; Kim, O J; Kim, I J; Kim, N K

    2015-01-01

    Coronary artery disease (CAD), a multifactorial disease, is a common cause of mortality in humans. Polymorphisms in the endothelial nitric oxide synthase (eNOS) gene (-786T>C, 4a4b, and 894G>T) have been previously associated with increased CAD risk. However, the sample size of this previous study was too small and limited to comprehensively define an association between eNOS polymorphisms and CAD; therefore, this analysis was duplicated with a larger population. The study was conducted on 559 patients with CAD and 574 healthy controls. Genetic DNA was extracted using the commercial G-DEX blood extraction kit and statistical analyses were performed on the GraphPad prism 4.0 and MedCalc 12.0 statistical software platforms. No single variant of the eNOS polymorphism was associated with CAD risk. The combination genotypes of eNOS -786TT/4a4b+4a4a [adjusted odds ratio (AOR) = 0.122; 95% confidence interval (CI): 0.042-0.358] and eNOS -786TC+CC/4b4b (AOR = 0.379; 95%CI: 0.147-0.979) were associated with decreased CAD incidence. Haplotype analysis revealed that the T-4a haplotype of eNOS -786T>C and 4a4b exerted a protective effect against CAD. The association between eNOS -786T>C and increased CAD risk was not replicated in this (larger) population. However, some combined genotypes showed a meaningful association with CAD risk. PMID:26662450

  7. Association of eNOS Gene Polymorphisms G894T and T-786C with Risk of Hepatorenal Syndrome.

    PubMed

    Seckin, Yuksel; Yigit, Ali; Yesilada, Elif; Gulbay, Gonca; Cagin, Yasir Furkan; Gozukara, Harika; Bılgıc, Yılmaz; Yildirim, Oguzhan; Turkoz, Yusuf; Aksungur, Zeynep

    2016-01-01

    Background. There are no studies investigating the relationship between endothelial nitric oxide synthase (eNOS) gene polymorphisms and hepatorenal syndrome (HRS). Aim. The purpose of this study is to elucidate whether eNOS gene polymorphisms (G894T and T-786C) play a role in the development of type-2 HRS. Methods. This study was carried out in a group of 92 patients with cirrhosis (44 patients with type-2 HRS and 48 without HRS) and 50 healthy controls. Polymorphisms were determined by polymerase chain reaction (PCR) and melting curve analysis. Results. We did not find any significant difference in allele and genotype distributions of the eNOS -T-786C polymorphism among the groups (p = 0.440). However, the frequency of GT (40.9%) and TT (13.6%) genotypes and mutant allele T (34.1%) for the eNOS G894T polymorphism were significantly higher (p < 0.001 and p < 0.001, resp.) in the HRS group than in both the stable cirrhosis (14.6%, 4.2%, and 11.5%, resp.) and the control (22.0%, 2.0%, and 13.0%, resp.) groups. Conclusion. The occurrence of mutant genotypes (GT/TT) and mutant allele T in eNOS -G894T polymorphisms should be considered as a potential risk factor in cirrhotic patients with HRS. PMID:27594880

  8. Association of eNOS Gene Polymorphisms G894T and T-786C with Risk of Hepatorenal Syndrome

    PubMed Central

    Yigit, Ali; Yesilada, Elif; Gulbay, Gonca; Bılgıc, Yılmaz; Yildirim, Oguzhan; Turkoz, Yusuf; Aksungur, Zeynep

    2016-01-01

    Background. There are no studies investigating the relationship between endothelial nitric oxide synthase (eNOS) gene polymorphisms and hepatorenal syndrome (HRS). Aim. The purpose of this study is to elucidate whether eNOS gene polymorphisms (G894T and T-786C) play a role in the development of type-2 HRS. Methods. This study was carried out in a group of 92 patients with cirrhosis (44 patients with type-2 HRS and 48 without HRS) and 50 healthy controls. Polymorphisms were determined by polymerase chain reaction (PCR) and melting curve analysis. Results. We did not find any significant difference in allele and genotype distributions of the eNOS -T-786C polymorphism among the groups (p = 0.440). However, the frequency of GT (40.9%) and TT (13.6%) genotypes and mutant allele T (34.1%) for the eNOS G894T polymorphism were significantly higher (p < 0.001 and p < 0.001, resp.) in the HRS group than in both the stable cirrhosis (14.6%, 4.2%, and 11.5%, resp.) and the control (22.0%, 2.0%, and 13.0%, resp.) groups. Conclusion. The occurrence of mutant genotypes (GT/TT) and mutant allele T in eNOS -G894T polymorphisms should be considered as a potential risk factor in cirrhotic patients with HRS.

  9. Role of endothelial nitric oxide synthase in diabetic nephropathy: lessons from diabetic eNOS knockout mice.

    PubMed

    Takahashi, Takamune; Harris, Raymond C

    2014-01-01

    Diabetic nephropathy (DN) is the leading cause of end-stage renal disease in many countries. The animal models that recapitulate human DN undoubtedly facilitate our understanding of this disease and promote the development of new diagnostic markers and therapeutic interventions. Based on the clinical evidence showing the association of eNOS dysfunction with advanced DN, we and others have created diabetic mice that lack eNOS expression and shown that eNOS-deficient diabetic mice exhibit advanced nephropathic changes with distinct features of progressive DN, including pronounced albuminuria, nodular glomerulosclerosis, mesangiolysis, and arteriolar hyalinosis. These studies clearly defined a critical role of eNOS in DN and developed a robust animal model of this disease, which enables us to study the pathogenic mechanisms of progressive DN. Further, recent studies with this animal model have explored the novel mechanisms by which eNOS deficiency causes advanced DN and provided many new insights into the pathogenesis of DN. Therefore, here we summarize the findings obtained with this animal model and discuss the roles of eNOS in DN, unresolved issues, and future investigations of this animal model study. PMID:25371905

  10. WLS-ENO: Weighted-least-squares based essentially non-oscillatory schemes for finite volume methods on unstructured meshes

    NASA Astrophysics Data System (ADS)

    Liu, Hongxu; Jiao, Xiangmin

    2016-06-01

    ENO (Essentially Non-Oscillatory) and WENO (Weighted Essentially Non-Oscillatory) schemes are widely used high-order schemes for solving partial differential equations (PDEs), especially hyperbolic conservation laws with piecewise smooth solutions. For structured meshes, these techniques can achieve high order accuracy for smooth functions while being non-oscillatory near discontinuities. For unstructured meshes, which are needed for complex geometries, similar schemes are required but they are much more challenging. We propose a new family of non-oscillatory schemes, called WLS-ENO, in the context of solving hyperbolic conservation laws using finite-volume methods over unstructured meshes. WLS-ENO is derived based on Taylor series expansion and solved using a weighted least squares formulation. Unlike other non-oscillatory schemes, the WLS-ENO does not require constructing sub-stencils, and hence it provides a more flexible framework and is less sensitive to mesh quality. We present rigorous analysis of the accuracy and stability of WLS-ENO, and present numerical results in 1-D, 2-D, and 3-D for a number of benchmark problems, and also report some comparisons against WENO.

  11. Shear stress stimulates phosphorylation of eNOS at Ser(635) by a protein kinase A-dependent mechanism

    NASA Technical Reports Server (NTRS)

    Boo, Yong Chool; Hwang, Jinah; Sykes, Michelle; Michell, Belinda J.; Kemp, Bruce E.; Lum, Hazel; Jo, Hanjoong

    2002-01-01

    Shear stress stimulates nitric oxide (NO) production by phosphorylating endothelial NO synthase (eNOS) at Ser(1179) in a phosphoinositide-3-kinase (PI3K)- and protein kinase A (PKA)-dependent manner. The eNOS has additional potential phosphorylation sites, including Ser(116), Thr(497), and Ser(635). Here, we studied these potential phosphorylation sites in response to shear, vascular endothelial growth factor (VEGF), and 8-bromocAMP (8-BRcAMP) in bovine aortic endothelial cells (BAEC). All three stimuli induced phosphorylation of eNOS at Ser(635), which was consistently slower than that at Ser(1179). Thr(497) was rapidly dephosphorylated by 8-BRcAMP but not by shear and VEGF. None of the stimuli phosphorylated Ser(116). Whereas shear-stimulated Ser(635) phosphorylation was not affected by phosphoinositide-3-kinase inhibitors wortmannin and LY-294002, it was blocked by either treating the cells with a PKA inhibitor H89 or infecting them with a recombinant adenovirus-expressing PKA inhibitor. These results suggest that shear stress stimulates eNOS by two different mechanisms: 1) PKA- and PI3K-dependent and 2) PKA-dependent but PI3K-independent pathways. Phosphorylation of Ser(635) may play an important role in chronic regulation of eNOS in response to mechanical and humoral stimuli.

  12. Association of eNOS Gene Polymorphisms G894T and T-786C with Risk of Hepatorenal Syndrome

    PubMed Central

    Yigit, Ali; Yesilada, Elif; Gulbay, Gonca; Bılgıc, Yılmaz; Yildirim, Oguzhan; Turkoz, Yusuf; Aksungur, Zeynep

    2016-01-01

    Background. There are no studies investigating the relationship between endothelial nitric oxide synthase (eNOS) gene polymorphisms and hepatorenal syndrome (HRS). Aim. The purpose of this study is to elucidate whether eNOS gene polymorphisms (G894T and T-786C) play a role in the development of type-2 HRS. Methods. This study was carried out in a group of 92 patients with cirrhosis (44 patients with type-2 HRS and 48 without HRS) and 50 healthy controls. Polymorphisms were determined by polymerase chain reaction (PCR) and melting curve analysis. Results. We did not find any significant difference in allele and genotype distributions of the eNOS -T-786C polymorphism among the groups (p = 0.440). However, the frequency of GT (40.9%) and TT (13.6%) genotypes and mutant allele T (34.1%) for the eNOS G894T polymorphism were significantly higher (p < 0.001 and p < 0.001, resp.) in the HRS group than in both the stable cirrhosis (14.6%, 4.2%, and 11.5%, resp.) and the control (22.0%, 2.0%, and 13.0%, resp.) groups. Conclusion. The occurrence of mutant genotypes (GT/TT) and mutant allele T in eNOS -G894T polymorphisms should be considered as a potential risk factor in cirrhotic patients with HRS. PMID:27594880

  13. The Attenuated Brucella abortus Strain 19 Invades, Persists in, and Activates Human Dendritic Cells, and Induces the Secretion of IL-12p70 but Not IL-23

    PubMed Central

    Weinhold, Mario; Eisenblätter, Martin; Jasny, Edith; Fehlings, Michael; Finke, Antje; Gayum, Hermine; Rüschendorf, Ursula; Renner Viveros, Pablo; Moos, Verena; Allers, Kristina; Schneider, Thomas; Schaible, Ulrich E.; Schumann, Ralf R.; Mielke, Martin E.; Ignatius, Ralf

    2013-01-01

    Background Bacterial vectors have been proposed as novel vaccine strategies to induce strong cellular immunity. Attenuated strains of Brucella abortus comprise promising vector candidates since they have the potential to induce strong CD4+ and CD8+ T-cell mediated immune responses in the absence of excessive inflammation as observed with other Gram-negative bacteria. However, some Brucella strains interfere with the maturation of dendritic cells (DCs), which is essential for antigen-specific T-cell priming. In the present study, we investigated the interaction of human monocyte-derived DCs with the smooth attenuated B. abortus strain (S) 19, which has previously been employed successfully to vaccinate cattle. Methodology/Principal findings We first looked into the potential of S19 to hamper the cytokine-induced maturation of DCs; however, infected cells expressed CD25, CD40, CD80, and CD86 to a comparable extent as uninfected, cytokine-matured DCs. Furthermore, S19 activated DCs in the absence of exogeneous stimuli, enhanced the expression of HLA-ABC and HLA-DR, and was able to persist intracellularly without causing cytotoxicity. Thus, DCs provide a cellular niche for persisting brucellae in vivo as a permanent source of antigen. S19-infected DCs produced IL-12/23p40, IL-12p70, and IL-10, but not IL-23. While heat-killed bacteria also activated DCs, soluble mediators were not involved in S19-induced activation of human DCs. HEK 293 transfectants revealed cellular activation by S19 primarily through engagement of Toll-like receptor (TLR)2. Conclusions/Significance Thus, as an immunological prerequisite for vaccine efficacy, B. abortus S19 potently infects and potently activates (most likely via TLR2) human DCs to produce Th1-promoting cytokines. PMID:23805193

  14. An Investigation of the Relationship between the eNOS Gene Polymorphism and Diagnosed Migraine.

    PubMed

    Güler, S; Gürkan, H; Tozkir, H; Turan, N; Çelik, Y

    2014-12-01

    We investigated the phenotype-genotype association of the following endothelial nitric oxide synthase (eNOS) gene polymorphisms, rs743506, rs2070744, rs1799983, rs180079, rs3918226, rs207468799 and rs148554851, in patients suffering from migraine living in Edirne, Turkey. A total of 175 individuals, who had been diagnosed with migraine between April 2013 and December 2013, at the Neurology Department, Trakya University Medical Faculty, Edirne, Turkey, and 125 healthy controls were recruited. The above gene polymorphisms were analyzed from genomic DNA in both patient and control groups, using the pyro-sequencing method. The eNOS rs1799983 TT genotype frequency in migraine patients who had a headache duration of longer than 24 hours was statistically significantly higher than in patients who had migraine attacks that lasted under 24 hours (p = 0.047). In terms of the AGGTGGA haplotype, the severity of headache was statistically significant, and was found to be severe in 61.0% (p = 0.0001). Also in terms of the AGGTGGA haplotype, the duration of headache was statistically significant, and was >24 hours in 56.0% of patients (p = 0.008). In our study, there was no significant genotypephenotype relationship between eNOS rs743506, rs2070744, rs1799983, rs180079, rs3918226, rs207468799 and rs148554851 gene polymorphisms and migraine patients with and without aura living in Edirne, Turkey. The AGGTGGA haplotype constitutes a risk in terms of the severity and the duration of headaches in patients with migraine. This risk is significantly higher in patients with migraine with aura than patients with migraine without aura.

  15. Persistence and degrading activity of free and immobilised allochthonous bacteria during bioremediation of hydrocarbon-contaminated soils.

    PubMed

    Rivelli, Valentina; Franzetti, Andrea; Gandolfi, Isabella; Cordoni, Sergio; Bestetti, Giuseppina

    2013-02-01

    Rhodococcus sp. and Pseudomonas sp. bioremediation experiments were carried out using free and immobilized cells on natural carrier material (corncob powder) in order to evaluate the feasibility of its use in the bioremediation of hydrocarbon-contaminated soils. Terminal restriction fragment length polymorphism analysis was performed on the 16S rRNA gene as molecular fingerprinting method in order to assess the persistence of inoculated strains in the soil over time. Immobilized Pseudomonas cells degraded hydrocarbons more efficiently in the short term compared to the free ones. Immobilization seemed also to increase cell growth and stability in the soil. Free and immobilized Rhodococcus cells showed comparable degradation percentages, probably due to the peculiarity of Rhodococcus cells to aggregate into irregular clusters in the presence of hydrocarbons as sole carbon source. It is likely that the cells were not properly adsorbed on the porous matrix as a result of the small size of its pores. When Rhodococcus and Pseudomonas cells were co-immobilized on the matrix, a competition established between the two strains, that probably ended in the exclusion of Pseudomonas cells from the pores. The organic matrix might act as protective agent, but it also possibly limited cell density. Nevertheless, when the cells were properly adsorbed on the porous matrix, the immobilization became a suitable bioremediation strategy.

  16. [The initial activity and persistance of an experimental larvicide with a base of Bacillus thuringiensis var. israelensis and a commercial preparation containing the organophosphorus insecticide temephos].

    PubMed

    Pussemier, L; De Borger, R

    1984-08-01

    The larvicide activity of the experimental preparation SAN 402 I WDC containing B. Thuringiensis var. Israelensis and that of Abate 500 E (44 % temephos) were tested on the larvae of Aedes aegypti. The studies were performed on the following media: distilled water, pure and buffered at pH 9, 7 and 4 and pond water whether or not free from materials in suspension. The activity of both preparations is not influenced by the composition of the media, exception made for the presence of materials in suspension. The persistance varies according to the kind of the media and the concentration level. It is in general rather low. Both preparations behave rather similar, the microbial insecticide however is more influenced by the presence of materials in suspension.

  17. eNOS Deficiency Acts through Endothelin to Aggravate sFlt-1–Induced Pre-Eclampsia–Like Phenotype

    PubMed Central

    Li, Feng; Hagaman, John R.; Kim, Hyung-Suk; Maeda, Nobuyo; Jennette, J. Charles; Faber, James E.; Karumanchi, S. Ananth; Smithies, Oliver

    2012-01-01

    Excess soluble fms-like tyrosine kinase 1 (sFlt-1) of vascular endothelial growth factor receptor 1 secreted from the placenta causes pre-eclampsia–like features by antagonizing vascular endothelial growth factor signaling, which can lead to reduced endothelial nitric oxide synthase (eNOS) activity; the effect of this concomitant decrease in eNOS activity is unknown. We tested whether the decrease in nitric oxide occurring in female mice lacking eNOS aggravates the pre-eclampsia–like phenotype induced by increased sFlt-1. Untreated eNOS-deficient female mice had higher BP than wild-type mice. Adenovirus-mediated overexpression of sFlt-1 increased systolic BP by approximately 27 mmHg and led to severe loss of fenestration of glomerular capillary endothelial cells in both eNOS-deficient and wild-type mice. However, only the eNOS-deficient sFlt-1 mice exhibited severe foot process effacement. Compared with wild-type sFlt-1 mice, eNOS-deficient sFlt-1 mice also showed markedly higher urinary albumin excretion (467±74 versus 174±23 μg/d), lower creatinine clearance (126±29 versus 452±63 μl/min), and more severe endotheliosis. Expression of preproendothelin-1 (ET-1) and its ETA receptor in the kidney was higher in eNOS-deficient sFlt-1 mice than in wild-type sFlt-1 mice. Furthermore, the selective ETA receptor antagonist ambrisentan attenuated the increases in BP and urinary albumin excretion and ameliorated endotheliosis in both wild-type and eNOS-deficient sFlt-1 mice. Ambrisentan improved creatinine clearance and podocyte effacement in eNOS-deficient sFlt-1 mice. In conclusion, reduced maternal eNOS/nitric oxide exacerbates the sFlt1-related pre-eclampsia–like phenotype through activation of the endothelin system. PMID:22282588

  18. Predictors of Student Persistence in the STEM Pipeline: Activities Outside the Classroom, Parent Aspirations, and Student Self-Beliefs using NELS:88 Data

    NASA Astrophysics Data System (ADS)

    Miller, Joelle A.

    Focusing on Science, Technology, Engineering and Mathematics (STEM) literacy is a national priority for the United States. As competition increases internationally for scientific and technological innovations, the United States is concentrating on building its STEM capacity (Stephens, 2011). Despite the numerous STEM reform efforts there continues to be a decline in STEM graduates and STEM competencies (McNally, 2012; Langdon, Mckittrick, Beede, Doms, & Khan, 2011; Herschback, 2011). With attention focused on increasing STEM college majors and occupations among the student population, the current research investigation centered on the role of parent aspirations, student self-beliefs, and activities outside the classroom to determine the outcome of middle and high school students choosing a STEM college major. Research suggested that students formulate their degree attainment during their middle and high school years, and even earlier (Roach, 2006; Maltese & Tai, 2011); therefore, it was logical to investigate STEM persistence during middle and high school years. The study analyzed NELS:88, a longitudinal national public data set created by the National Center for Educational Statistics that used 12,144 participants. The students' self-reported data spanned over a 12-year period. Students completed five surveys in the NELS:88 data collection (NCES, 2011). Binary and multivariate logistical regressions determined if activities outside the classroom, parent aspirations, and student self-beliefs influenced STEM college majors. Conclusions of the study found significant relationships between the variables and STEM persistence. Individuals who participated in STEM activities after school were more likely to major in STEM (p<.001,Exp(B)=1.106). There was a significant positive relationship between parent aspirations and increased odds of choosing a STEM major (p<.0001, Exp(B)=1.041). There was a significant relationship between student self-beliefs and choosing a STEM

  19. Activity and function recognition for moving and static objects in urban environments from wide-area persistent surveillance inputs

    NASA Astrophysics Data System (ADS)

    Levchuk, Georgiy; Bobick, Aaron; Jones, Eric

    2010-04-01

    In this paper, we describe results from experimental analysis of a model designed to recognize activities and functions of moving and static objects from low-resolution wide-area video inputs. Our model is based on representing the activities and functions using three variables: (i) time; (ii) space; and (iii) structures. The activity and function recognition is achieved by imposing lexical, syntactic, and semantic constraints on the lower-level event sequences. In the reported research, we have evaluated the utility and sensitivity of several algorithms derived from natural language processing and pattern recognition domains. We achieved high recognition accuracy for a wide range of activity and function types in the experiments using Electro-Optical (EO) imagery collected by Wide Area Airborne Surveillance (WAAS) platform.

  20. A family of high-order targeted ENO schemes for compressible-fluid simulations

    NASA Astrophysics Data System (ADS)

    Fu, Lin; Hu, Xiangyu Y.; Adams, Nikolaus A.

    2016-01-01

    Although classical WENO schemes have achieved great success and are widely accepted, they exhibit several shortcomings. They are too dissipative for direct simulations of turbulence and lack robustness when very-high-order versions are applied to complex flows. In this paper, we propose a family of high-order targeted ENO schemes which are applicable for compressible-fluid simulations involving a wide range of flow scales. In order to increase the numerical robustness as compared to very-high-order classical WENO schemes, the reconstruction dynamically assembles a set of low-order candidate stencils with incrementally increasing width. While discontinuities and small-scale fluctuations are efficiently separated, the numerical dissipation is significantly diminished by an ENO-like stencil selection, which either applies a candidate stencil with its original linear weight, or removes its contribution when it is crossed by a discontinuity. The background linear scheme is optimized under the constraint of preserving an approximate dispersion-dissipation relation. By means of quasi-linear analyses and practical numerical experiments, a set of case-independent parameters is determined. The general formulation of arbitrarily high-order schemes is presented in a straightforward way. A variety of benchmark-test problems, including broadband waves, strong shock and contact discontinuities are studied. Compared to well-established classical WENO schemes, the present schemes exhibit significantly improved robustness, low numerical dissipation and sharp discontinuity capturing. They are particularly suitable for DNS and LES of shock-turbulence interactions.

  1. A numerical study of ENO and TVD schemes for shock capturing

    NASA Technical Reports Server (NTRS)

    Chang, Shih-Hung; Liou, Meng-Sing

    1988-01-01

    The numerical performance of a second-order upwind-based total variation diminishing (TVD) scheme and that of a uniform second-order essentially non-oscillatory (ENO) scheme for shock capturing are compared. The TVD scheme used is a modified version of Liou, using the flux-difference splitting (FDS) of Roe and his superbee function as the limiter. The construction of the basic ENO scheme is based on Harten, Engquist, Osher, and Chakravarthy, and the 2-D extensions are obtained by using a Strang-type of fractional-step time-splitting method. Numerical results presented include both steady and unsteady, 1-D and 2-D calculations. All the chosen test problems have exact solutions so that numerical performance can be measured by comparing the computer results to them. For 1-D calculations, the standard shock-tube problems of Sod and Lax are chosen. A very strong shock-tube problem, with the initial density ratio of 400 to 1 and pressure ratio of 500 to 1, is also used to study the behavior of the two schemes. For 2-D calculations, the shock wave reflection problems are adopted for testing. The cases presented in this report include flows with Mach numbers of 2.9, 5.0, and 10.0.

  2. Central Role of eNOS in the Maintenance of Endothelial Homeostasis

    PubMed Central

    Rodriguez-Mateos, Ana; Kelm, Malte

    2015-01-01

    Abstract Significance: Disruption of endothelial function is considered a key event in the development and progression of atherosclerosis. Endothelial nitric oxide synthase (eNOS) is a central regulator of cellular function that is important to maintain endothelial homeostasis. Recent Advances: Endothelial homeostasis encompasses acute responses such as adaption of flow to tissue's demand and more sustained responses to injury such as re-endothelialization and sprouting of endothelial cells (ECs) and attraction of circulating angiogenic cells (CAC), both of which support repair of damaged endothelium. The balance and the intensity of endothelial damage and repair might be reflected by changes in circulating endothelial microparticles (EMP) and CAC. Flow-mediated vasodilation (FMD) is a generally accepted clinical read-out of NO-dependent vasodilation, whereas EMP are upcoming prognostically validated markers of endothelial injury and CAC are reflective of the regenerative capacity with both expressing a functional eNOS. These markers can be integrated in a clinical endothelial phenotype, reflecting the net result between damage from risk factors and endogenous repair capacity with NO representing a central signaling molecule. Critical Issues: Improvements of reproducibility and observer independence of FMD measurements and definitions of relevant EMP and CAC subpopulations warrant further research. Future Directions: Endothelial homeostasis may be a clinical therapeutic target for cardiovascular health maintenance. Antioxid. Redox Signal. 22, 1230–1242. PMID:25330054

  3. eNOS tag SNP haplotypes in hypertensive disorders of pregnancy.

    PubMed

    Muniz, Ludmila; Luizon, Marcelo R; Palei, Ana C T; Lacchini, Riccardo; Duarte, Geraldo; Cavalli, Ricardo C; Tanus-Santos, Jose E; Sandrim, Valeria C

    2012-12-01

    Haplotypes formed by polymorphisms (T-786C, rs2070744; a variable number of tandem repeats in intron 4, and Glu298Asp, rs1799983) of the eNOS gene were associated previously with gestational hypertension (GH) and preeclampsia (PE). However, no study has explored the Tag SNPs rs743506 and rs7830 in these disorders. The aim of the current study was to compare the distribution of the genotypes and haplotypes formed by the five eNOS polymorphisms mentioned among healthy pregnant (HP, n=122), GH (n=138), and PE (n=157). The haplotype formed by "C b G G C" was more frequent in HP compared to GH and PE (p=0.0071), which is supported by previous findings that demonstrated the association of the combination "C b G" with a higher level of nitrite (NO marker). Our results suggest a protective effect of the haplotype "C b G G C" against the development of hypertensive disorders of pregnancy. PMID:23062210

  4. Systems for persistent surveillance

    NASA Astrophysics Data System (ADS)

    Lewis, Keith

    2011-09-01

    The requirements for a persistent wide-area surveillance system are discussed in the context of evolving military operations. Significant emphasis has been placed on the development of new sensing technologies to meet the challenges posed by asymmetric threats. Within the UK, the Electro-Magnetic Remote Sensing Defence Technology Centre (EMRS DTC) has supported the research and development of new capabilities including radio-frequency (RF) and electro-optic (EO) systems, as well as work on sensor exploitation, with a goal of developing solutions for enhancing situational awareness. This activity has been supported by field trials to determine the efficacy of competing technologies in relation to realistic threat scenarios.

  5. Computational estimation of the distribution of L-type Ca(2+) channels in motoneurons based on variable threshold of activation of persistent inward currents.

    PubMed

    Bui, Tuan V; Ter-Mikaelian, Maria; Bedrossian, Diane; Rose, P Ken

    2006-01-01

    In the presence of neuromodulators such as serotonin and noradrenaline, motoneurons exhibit persistent inward currents (PICs) that serve to amplify synaptic inputs. A major component of these PICs is mediated by L-type Ca(2+) channels. Estimates based on electrophysiological studies indicate that these channels are located on the dendrites, but immunohistochemical studies of their precise distribution have yielded different results. Our goal was to determine the distribution of these channels using computational methods. A theoretical analysis of the activation of PICs by a somatic current injection in the absence or presence of synaptic activity suggests that L-type Ca(2+) channels may be segregated to discrete hot spots 25-200 microm long and centered 100-400 microm from the soma in the dendritic tree. Compartmental models based on detailed anatomical measurements of the structure of feline neck motoneurons with L-type Ca(2+) channels incorporated in these regions produced plateau potentials resulting from PIC activation. Furthermore, we replicated the experimental observation that the somatic threshold at which PICs were activated was depolarized by tonic activation of inhibitory synapses and hyperpolarized by tonic activation of excitatory synapses. Models with L-type Ca(2+) channels distributed uniformly were unable to replicate the change in somatic threshold of PIC activation. Therefore we conclude that the set of L-type Ca(2+) channels mediating plateau potentials is restricted to discrete regions in the dendritic tree. Furthermore, this distribution leads to the compartmentalization of the dendritic tree of motoneurons into subunits whose sequential activation lead to the graded amplification of synaptic inputs.

  6. Antiprion Activity of DB772 and Related Monothiophene- and Furan-Based Analogs in a Persistently Infected Ovine Microglia Culture System.

    PubMed

    Dinkel, Kelcey D; Stanton, James B; Boykin, David W; Stephens, Chad E; Madsen-Bouterse, Sally A; Schneider, David A

    2016-09-01

    The transmissible spongiform encephalopathies are fatal neurodegenerative disorders characterized by the misfolding of the native cellular prion protein (PrP(C)) into the accumulating, disease-associated isoform (PrP(Sc)). Despite extensive research into the inhibition of prion accumulation, no effective treatment exists. Previously, we demonstrated the inhibitory activity of DB772, a monocationic phenyl-furan-benzimidazole, against PrP(Sc) accumulation in sheep microglial cells. In an effort to determine the effect of structural substitutions on the antiprion activity of DB772, we employed an in vitro strategy to survey a library of structurally related, monothiophene- and furan-based compounds for improved inhibitory activity. Eighty-nine compounds were screened at 1 μM for effects on cell viability and prion accumulation in a persistently infected ovine microglia culture system. Eleven compounds with activity equivalent to or higher than that of DB772 were identified as preliminary hit compounds. For the preliminary hits, cytotoxicities and antiprion activities were compared to calculate the tissue culture selectivity index. A structure-activity relationship (SAR) analysis was performed to determine molecular components contributing to antiprion activity. To investigate potential mechanisms of inhibition, effects on PrP(C) and PrP(Sc) were examined. While inhibition of total PrP(C) was not observed, the results suggest that a potential target for inhibition at biologically relevant concentrations is through PrP(C) misfolding to PrP(Sc) Further, SAR analysis suggests that two structural elements were associated with micromolar antiprion activity. Taken together, the described data provide a foundation for deeper investigation into untested DB compounds and in the design of effective therapeutics. PMID:27381401

  7. Antiprion Activity of DB772 and Related Monothiophene- and Furan-Based Analogs in a Persistently Infected Ovine Microglia Culture System

    PubMed Central

    Dinkel, Kelcey D.; Stanton, James B.; Boykin, David W.; Stephens, Chad E.; Madsen-Bouterse, Sally A.

    2016-01-01

    The transmissible spongiform encephalopathies are fatal neurodegenerative disorders characterized by the misfolding of the native cellular prion protein (PrPC) into the accumulating, disease-associated isoform (PrPSc). Despite extensive research into the inhibition of prion accumulation, no effective treatment exists. Previously, we demonstrated the inhibitory activity of DB772, a monocationic phenyl-furan-benzimidazole, against PrPSc accumulation in sheep microglial cells. In an effort to determine the effect of structural substitutions on the antiprion activity of DB772, we employed an in vitro strategy to survey a library of structurally related, monothiophene- and furan-based compounds for improved inhibitory activity. Eighty-nine compounds were screened at 1 μM for effects on cell viability and prion accumulation in a persistently infected ovine microglia culture system. Eleven compounds with activity equivalent to or higher than that of DB772 were identified as preliminary hit compounds. For the preliminary hits, cytotoxicities and antiprion activities were compared to calculate the tissue culture selectivity index. A structure-activity relationship (SAR) analysis was performed to determine molecular components contributing to antiprion activity. To investigate potential mechanisms of inhibition, effects on PrPC and PrPSc were examined. While inhibition of total PrPC was not observed, the results suggest that a potential target for inhibition at biologically relevant concentrations is through PrPC misfolding to PrPSc. Further, SAR analysis suggests that two structural elements were associated with micromolar antiprion activity. Taken together, the described data provide a foundation for deeper investigation into untested DB compounds and in the design of effective therapeutics. PMID:27381401

  8. Characterisation of eye-lens DNases: long term persistence of activity in post apoptotic lens fibre cells.

    PubMed

    Arruti, C; Chaudun, E; De Maria, A; Courtois, Y; Counis, M F

    1995-01-01

    Fibre cells in the ocular lens exhibit a constitutive apoptotic process of nuclear degradation that includes chromatin breakage, generating a ladder pattern of DNA fragments. This process is intrinsic to the normal terminal differentiation program. Despite the loss of nucleus and cytoplasmic organelles, the terminal differentiated fibre cells remain in the lens during the whole life span of the individual. The lens cells thus provide a unique system in which to determine the presence and fate of endonucleases once the chromatin has been cleaved. We report here on the presence of DNase activity in nucleated and anucleated lens cells. Using a nuclease gel assay and double-stranded DNA as substrate, we found active 30 and 60 kDa DNases. The enzymatic activities were Ca(2+), Mg(2+) dependent, and active at neutral pH. The relative amount of these forms changed during development and aging of the lens fibre cells. Both forms were inhibited by Zn(2+), aurintricarboxylic acid, and G-actin. The proteins were also separated by SDS-PAGE, renatured after removing SDS and incubated in the presence of native DNA adsorbed to a membrane. Therefore it was possible to demonstrate, by means of a nick translation reaction, that the enzymes produced single strand cuts. Based on these findings we propose that these chick lens nucleases are probably related to DNase I.

  9. Characterisation of eye-lens DNases: long term persistence of activity in post apoptotic lens fibre cells.

    PubMed

    Arruti, C; Chaudun, E; De Maria, A; Courtois, Y; Counis, M F

    1995-01-01

    Fibre cells in the ocular lens exhibit a constitutive apoptotic process of nuclear degradation that includes chromatin breakage, generating a ladder pattern of DNA fragments. This process is intrinsic to the normal terminal differentiation program. Despite the loss of nucleus and cytoplasmic organelles, the terminal differentiated fibre cells remain in the lens during the whole life span of the individual. The lens cells thus provide a unique system in which to determine the presence and fate of endonucleases once the chromatin has been cleaved. We report here on the presence of DNase activity in nucleated and anucleated lens cells. Using a nuclease gel assay and double-stranded DNA as substrate, we found active 30 and 60 kDa DNases. The enzymatic activities were Ca(2+), Mg(2+) dependent, and active at neutral pH. The relative amount of these forms changed during development and aging of the lens fibre cells. Both forms were inhibited by Zn(2+), aurintricarboxylic acid, and G-actin. The proteins were also separated by SDS-PAGE, renatured after removing SDS and incubated in the presence of native DNA adsorbed to a membrane. Therefore it was possible to demonstrate, by means of a nick translation reaction, that the enzymes produced single strand cuts. Based on these findings we propose that these chick lens nucleases are probably related to DNase I. PMID:17180015

  10. L-Arginine ameliorates cardiac left ventricular oxidative stress by upregulating eNOS and Nrf2 target genes in alloxan-induced hyperglycemic rats

    SciTech Connect

    Ramprasath, Tharmarajan; Hamenth Kumar, Palani; Syed Mohamed Puhari, Shanavas; Senthil Murugan, Ponniah; Vasudevan, Varadaraj; Selvam, Govindan Sadasivam

    2012-11-23

    Highlights: Black-Right-Pointing-Pointer L-Arginine treatment reduced the metabolic disturbances in diabetic animals. Black-Right-Pointing-Pointer Antioxidant marker proteins were found high in myocardium by L-arginine treatment. Black-Right-Pointing-Pointer Elevated antioxidant status, mediates the reduced TBA-reactivity in left ventricle. Black-Right-Pointing-Pointer L-Arginine treatment enhanced the Nrf2 and eNOS signaling in left ventricle. Black-Right-Pointing-Pointer Improved cell survival signaling by arginine, offers a novel tactic for targeting. -- Abstract: Hyperglycemia is independently related with excessive morbidity and mortality in cardiovascular disorders. L-Arginine-nitric oxide (NO) pathway and the involvement of NO in modulating nuclear factor-E2-related factor-2 (Nrf2) signaling were well established. In the present study we investigated, whether L-arginine supplementation would improve the myocardial antioxidant defense under hyperglycemia through activation of Nrf2 signaling. Diabetes was induced by alloxan monohydrate (90 mg kg{sup -1} body weight) in rats. Both non-diabetic and diabetic group of rats were divided into three subgroups and they were administered either with L-arginine (2.25%) or L-NAME (0.01%) in drinking water for 12 days. Results showed that L-arginine treatment reduced the metabolic disturbances in diabetic rats. Antioxidant enzymes and glutathione levels were found to be increased in heart left ventricles, thereby reduction of lipid peroxidation by L-arginine treatment. Heart histopathological analysis further validates the reversal of typical diabetic characteristics consisting of alterations in myofibers and myofibrillary degeneration. qRT-PCR studies revealed that L-arginine treatment upregulated the transcription of Akt and downregulated NF-{kappa}B. Notably, transcription of eNOS and Nrf2 target genes was also upregulated, which were accompanied by enhanced expression of Nrf2 in left ventricular tissue from diabetic

  11. Lupus anticoagulant and history of thrombosis are not associated with persistent endothelial cell activation in systemic lupus erythematosus

    PubMed Central

    Frijns, C J M; Derksen, R H W M; De Groot, PH G; Algra, A; Fijnheer, R

    2001-01-01

    Antiphospholipid antibodies (aPL), especially lupus anticoagulant (LAC), characterize systemic lupus erythematosus (SLE) patients at increased risk for arterial and venous thromboembolic complications. It has been reported that purified human anti-phospholipid antibodies cause endothelial cell activation in in vitro experiments. In order to investigate whether increased endothelial cell activation is associated with thromboembolic events in SLE patients with LAC, we measured plasma levels of thrombomodulin (TM), von Willebrand factor (vWf), sP-selectin, vascular cell adhesion molecule-1 (sVCAM-1) and ED1-fibronectin in a study of 76 patients with SLE. Patients were subdivided on the basis of: no history of thrombosis and LAC-negative (n = 22) or LAC-positive (n = 17); positive history of thrombosis and LAC-negative (n = 16) or LAC-positive (n = 21). The median SLE disease activity index (SLEDAI) was 4. Although concentrations of sTM, vWf, sP-selectin and sVCAM-1 were significantly elevated in SLE compared with values in healthy controls, they did not differ between the four groups, between patients with or without history of thrombosis, and between patients with or without LAC. Presence of anticardiolipin antibodies could not explain these negative findings. Adjustment of the concentrations for significantly associated variables, such as age, hypertension, smoking, immunosuppressive treatment and concentrations of creatinine, cholesterol and homocysteine, did not change the main results of the study. Only sTM was significantly lower in patients with both LAC and thrombosis than in patients without both these features after adjustment for serum creatinine concentrations. In conclusion, we did not find an association between endothelial cell activation and presence of LAC or history of thrombosis in SLE. PMID:11472438

  12. Virus-specific T cells engineered to coexpress tumor-specific receptors: persistence and antitumor activity in individuals with neuroblastoma.

    PubMed

    Pule, Martin A; Savoldo, Barbara; Myers, G Doug; Rossig, Claudia; Russell, Heidi V; Dotti, Gianpietro; Huls, M Helen; Liu, Enli; Gee, Adrian P; Mei, Zhuyong; Yvon, Eric; Weiss, Heidi L; Liu, Hao; Rooney, Cliona M; Heslop, Helen E; Brenner, Malcolm K

    2008-11-01

    Cytotoxic T lymphocytes (CTLs) directed to nonviral tumor-associated antigens do not survive long term and have limited antitumor activity in vivo, in part because such tumor cells typically lack the appropriate costimulatory molecules. We therefore engineered Epstein-Barr virus (EBV)-specific CTLs to express a chimeric antigen receptor directed to the diasialoganglioside GD2, a nonviral tumor-associated antigen expressed by human neuroblastoma cells. We reasoned that these genetically engineered lymphocytes would receive optimal costimulation after engagement of their native receptors, enhancing survival and antitumor activity mediated through their chimeric receptors. Here we show in individuals with neuroblastoma that EBV-specific CTLs expressing a chimeric GD2-specific receptor indeed survive longer than T cells activated by the CD3-specific antibody OKT3 and expressing the same chimeric receptor but lacking virus specificity. Infusion of these genetically modified cells seemed safe and was associated with tumor regression or necrosis in half of the subjects tested. Hence, virus-specific CTLs can be modified to function as tumor-directed effector cells.

  13. Virus-specific T cells engineered to coexpress tumor-specific receptors: persistence and antitumor activity in individuals with neuroblastoma

    PubMed Central

    Pule, Martin A; Savoldo, Barbara; Myers, G Doug; Rossig, Claudia; Russell, Heidi V; Dotti, Gianpietro; Huls, M Helen; Liu, Enli; Gee, Adrian P; Mei, Zhuyong; Yvon, Eric; Weiss, Heidi L; Liu, Hao; Rooney, Cliona M; Heslop, Helen E; Brenner, Malcolm K

    2009-01-01

    Cytotoxic T lymphocytes (CTLs) directed to nonviral tumor–associated antigens do not survive long term and have limited antitumor activity in vivo, in part because such tumor cells typically lack the appropriate costimulatory molecules. We therefore engineered Epstein-Barr virus (EBV)-specific CTLs to express a chimeric antigen receptor directed to the diasialoganglioside GD2, a nonviral tumor–associated antigen expressed by human neuroblastoma cells. We reasoned that these genetically engineered lymphocytes would receive optimal costimulation after engagement of their native receptors, enhancing survival and antitumor activity mediated through their chimeric receptors. Here we show in individuals with neuroblastoma that EBV-specific CTLs expressing a chimeric GD2-specific receptor indeed survive longer than T cells activated by the CD3-specific antibody OKT3 and expressing the same chimeric receptor but lacking virus specificity. Infusion of these genetically modified cells seemed safe and was associated with tumor regression or necrosis in half of the subjects tested. Hence, virus-specific CTLs can be modified to function as tumor-directed effector cells. PMID:18978797

  14. Caveolin-1 mediates endotoxin inhibition of endothelin-1-induced endothelial nitric oxide synthase activity in liver sinusoidal endothelial cells.

    PubMed

    Kwok, Willson; Lee, Sang Ho; Culberson, Cathy; Korneszczuk, Katarzyna; Clemens, Mark G

    2009-11-01

    Endothelin-1 (ET-1) plays a key role in the regulation of endothelial nitric oxide synthase (eNOS) activation in liver sinusoidal endothelial cells (LSECs). In the presence of endotoxin, an increase in caveolin-1 (Cav-1) expression impairs ET-1/eNOS signaling; however, the molecular mechanism is unknown. The objective of this study was to investigate the molecular mechanism of Cav-1 in the regulation of LPS suppression of ET-1-mediated eNOS activation in LSECs by examining the effect of caveolae disruption using methyl-beta-cyclodextrin (CD) and filipin. Treatment with 5 mM CD for 30 min increased eNOS activity (+255%, P < 0.05). A dose (0.25 microg/ml) of filipin for 30 min produced a similar effect (+111%, P < 0.05). CD induced the perinuclear localization of Cav-1 and eNOS and stimulated NO production in the same region. Readdition of 0.5 mM cholesterol to saturate CD reversed these effects. Both the combined treatment with CD and ET-1 (CD + ET-1) and with filipin and ET-1 stimulated eNOS activity; however, pretreatment with endotoxin (LPS) abrogated these effects. Following LPS pretreatment, CD + ET-1 failed to stimulate eNOS activity (+51%, P > 0.05), which contributed to the reduced levels of eNOS-Ser1177 phosphorylation and eNOS-Thr495 dephosphorylation, the LPS/CD-induced overexpression and translocation of Cav-1 in the perinuclear region, and the increased perinuclear colocalization of eNOS with Cav-1. These results supported the hypothesis that Cav-1 mediates the action of endotoxin in suppressing ET-1-mediated eNOS activation and demonstrated that the manipulation of caveolae produces significant effects on ET-1-mediated eNOS activity in LSECs.

  15. Persistent Macrophage/Microglial Activation and Myelin Disruption after Experimental Autoimmune Encephalomyelitis in Tissue Inhibitor of Metalloproteinase-1-Deficient Mice

    PubMed Central

    Crocker, Stephen J.; Whitmire, Jason K.; Frausto, Ricardo F.; Chertboonmuang, Parntip; Soloway, Paul D.; Whitton, J. Lindsay; Campbell, Iain L.

    2006-01-01

    Increased leukocyte trafficking into the parenchyma during inflammatory responses in the central nervous system (CNS) is facilitated by the extracellular proteolytic activities of matrix metalloproteinases that are regulated, in part, by the endogenous tissue inhibitors of metalloproteinases (TIMPs). In experimental autoimmune encephalomyelitis (EAE), TIMP-1 gene expression is induced in astrocytes surrounding inflammatory lesions in the CNS. The physiological importance of this temporal and spatial relationship is not clear. Herein, we have addressed the functional role of TIMP-1 in a myelin oligodendrocyte glycoprotein (MOG35-55)-induced model of EAE using TIMP-1-deficient (TIMP-1−/−) C57BL/6 mice. Although CD4+ T-cell immune responses to myelin in wild-type (WT) and TIMP-1−/− mice were similar, analysis of CNS tissues from TIMP-1−/− mice after EAE revealed more severe myelin pathology than that of WT mice. This disruption of myelin was associated with both increased lymphocyte infiltration and microglial/macrophage accumulation in the brain parenchyma. These findings suggest that induction of TIMP-1 by astrocytes during EAE in WT mice represents an inherent cytoprotective response that mitigates CNS myelin injury through the regulation of both immune cell infiltration and microglial activation. PMID:17148673

  16. Active Life Expectancy In The Older US Population, 1982-2011: Differences Between Blacks And Whites Persisted.

    PubMed

    Freedman, Vicki A; Spillman, Brenda C

    2016-08-01

    Understanding long-range trends in longevity and disability is useful for projecting the likely impact of the baby-boom generation on long-term care utilization and spending. We examine changes in active life expectancy in the United States from 1982 to 2011 for white and black adults ages sixty-five and older. For whites, longevity increased, disability was postponed to older ages, the locus of care shifted from nursing facilities to community settings, and the proportion of life at older ages spent without disability increased. In contrast, for blacks, longevity increases were accompanied by smaller postponements in disability, and the percentage of remaining life spent active remained stable and well below that of whites. Older black women were especially disadvantaged in 2011 in terms of the proportion of years expected to be lived without disability. Public health measures directed at older black adults-particularly women-are needed to offset impending pressures on the long-term care delivery system as the result of population aging.

  17. Active Life Expectancy In The Older US Population, 1982-2011: Differences Between Blacks And Whites Persisted.

    PubMed

    Freedman, Vicki A; Spillman, Brenda C

    2016-08-01

    Understanding long-range trends in longevity and disability is useful for projecting the likely impact of the baby-boom generation on long-term care utilization and spending. We examine changes in active life expectancy in the United States from 1982 to 2011 for white and black adults ages sixty-five and older. For whites, longevity increased, disability was postponed to older ages, the locus of care shifted from nursing facilities to community settings, and the proportion of life at older ages spent without disability increased. In contrast, for blacks, longevity increases were accompanied by smaller postponements in disability, and the percentage of remaining life spent active remained stable and well below that of whites. Older black women were especially disadvantaged in 2011 in terms of the proportion of years expected to be lived without disability. Public health measures directed at older black adults-particularly women-are needed to offset impending pressures on the long-term care delivery system as the result of population aging. PMID:27503957

  18. Development of confocal immunofluorescence FRET microscopy to Investigate eNOS and GSNOR localization and interaction in pulmonary endothelial cells

    NASA Astrophysics Data System (ADS)

    Rehman, Shagufta; Brown-Steinke, Kathleen; Palmer, Lisa; Periasamy, Ammasi

    2015-03-01

    Confocal FRET microscopy is a widely used technique for studying protein-protein interactions in live or fixed cells. Endothelial nitric oxide synthase (eNOS) and S-nitrosoglutathione reductase (GSNOR) are enzymes involved in regulating the bioavailability of S-nitrosothiols (SNOs) in the pulmonary endothelium and have roles in the development of pulmonary arterial hypertension. Labeling of endogenous proteins to better understand a disease process can be challenging. We have used immunofluorescence to detect endogenous eNOS and GSNOR in primary pulmonary endothelial cells to co-localize these proteins as well as to study their interaction by FRET. The challenge has been in selecting the right immunofluorescence labeling condition, right antibody, the right blocking reagent, the right FRET pair and eliminating cross-reactivity of secondary antibodies. We have used Alexa488 and Alexa568 as a FRET pair. After a series of optimizations, the data from Confocal Laser Scanning Microscopy (CLSM) demonstrate co-localization of eNOS and GSNOR in the perinuclear region of the pulmonary endothelial cell primarily within the cis-Golgi with lower levels of co-localization seen within the trans-Golgi. FRET studies demonstrate, for the first time, interaction between eNOS and GSNOR in both murine and bovine pulmonary endothelial cells. Further characterization of eNOSGSNOR interaction and the subcellular location of this interaction will provide mechanistic insight into the importance of S-nitrosothiol signaling in pulmonary biology, physiology and pathology.

  19. Molecular beacons can assess changes in expression and 3'-polyadenylation of human eNOS mRNA.

    PubMed

    Jones, Rachel; Baker, Meredith B; Weber, Martina; Harrison, David G; Bao, Gang; Searles, Charles D

    2009-03-01

    The endothelium plays an essential role in maintaining vascular homeostasis, and it fulfills this role by modulating intracellular signaling and gene expression in response to chemical and mechanical stimuli. Assessing changes in endothelial gene expression is essential to understanding how physiological and pathophysiological processes modulate vascular homeostasis. Here we describe the use of molecular beacons to rapidly and quantitatively assess expression and 3'-polyadenylation of a gene that is important for vascular homeostasis, endothelial nitric oxide synthase (eNOS). Single- and dual-fluorescence resonance energy transfer (FRET) molecular beacon hybridization assays were developed to measure changes in mRNA levels and 3'-polyadenylation, respectively, in primary human endothelial cell cultures subjected to laminar shear stress or statin treatment. Optimized beacon hybridization assays took approximately 15 min to perform, and eNOS mRNA levels were validated by quantitative real-time RT-PCR. Competitive inhibition assays and posttranscriptional silencing of eNOS expression were used to verify the specificity of molecular beacon fluorescence. Finally, the dual-FRET method was used to assess eNOS polyadenylation in tissues isolated from mice subjected to exercise training. These data demonstrate that molecular beacons can be used to rapidly and efficiently measure endothelial gene expression and 3'-polyadenylation. This approach could easily be adapted for studies of other endothelial genes and has promise for applications in live endothelial cells.

  20. Association of eNOS gene polymorphisms with essential hypertension in the Han population in southwestern China.

    PubMed

    Li, J; Cun, Y; Tang, W R; Wang, Y; Li, S N; Ouyang, H R; Wu, Y R; Yu, H J; Xiao, C J

    2011-01-01

    Endothelial nitric oxide synthase (eNOS) plays an important role in maintaining blood pressure homeostasis and vascular integrity. Polymorphisms in the eNOS gene have been found to be associated with hypertension in different human populations, including Northern and Southern Chinese Han populations. To examine the relationship of three eNOS gene polymorphisms, T-786C (rs2070744), G894T (rs1799983), and G10T (rs7830), with hypertension in the Han population in southwestern China, we carried out a study of the genotypes of three SNPs in 510 hypertensive and 510 normotensive subjects from the Yunnan Province by using PCR-RFLP and sequencing. Our SNP analyses showed that the distribution of the T-786C polymorphism did not differ between patients and controls, and that G894T and G10T are significantly associated with hypertension in females, adjusted for covariates. Compared with the other haplotypes, haplotype H1 (TGG), carrying protective 10G and 894G alleles, significantly decreased the risk of increased essential hypertension in females, with an odds ratio of 0.68 (P = 10(-5)). These results suggest that the eNOS polymorphism is one of the factors contributing to the predisposition for essential hypertension in the Han population in southwestern China. PMID:21968727

  1. Modeling the influence of temperature, water activity and water mobility on the persistence of Salmonella in low-moisture foods.

    PubMed

    Farakos, S M Santillana; Frank, J F; Schaffner, D W

    2013-09-01

    Salmonella can survive in low-moisture foods for long periods of time. Reduced microbial inactivation during heating is believed to be due to the interaction of cells and water, and is thought to be related to water activity (a(w)). Little is known about the role of water mobility in influencing the survival of Salmonella in low-moisture foods. The aim of this study was to determine how the physical state of water in low-moisture foods influences the survival of Salmonella and to use this information to develop mathematical models that predict the behavior of Salmonella in these foods. Whey protein powder of differing water mobilities was produced by pH adjustment and heat denaturation, and then equilibrated to aw levels between 0.19±0.03 and 0.54±0.02. Water mobility was determined by wide-line proton-NMR. Powders were inoculated with a four-strain cocktail of Salmonella, vacuum-sealed and stored at 21, 36, 50, 60, 70 and 80°C. Survival data was fitted to the log-linear, the Geeraerd-tail, the Weibull, the biphasic-linear and the Baranyi models. The model with the best ability to describe the data over all temperatures, water activities and water mobilities (f(test)activity significantly influenced the survival of Salmonella at all temperatures, survival increasing with decreasing a(w). Water mobility did not significantly influence survival independent of a(w). Secondary models were useful in predicting the survival of Salmonella in various low-moisture foods providing a correlation of R=0.94 and an acceptable prediction performance of 81

  2. Modeling the influence of temperature, water activity and water mobility on the persistence of Salmonella in low-moisture foods.

    PubMed

    Farakos, S M Santillana; Frank, J F; Schaffner, D W

    2013-09-01

    Salmonella can survive in low-moisture foods for long periods of time. Reduced microbial inactivation during heating is believed to be due to the interaction of cells and water, and is thought to be related to water activity (a(w)). Little is known about the role of water mobility in influencing the survival of Salmonella in low-moisture foods. The aim of this study was to determine how the physical state of water in low-moisture foods influences the survival of Salmonella and to use this information to develop mathematical models that predict the behavior of Salmonella in these foods. Whey protein powder of differing water mobilities was produced by pH adjustment and heat denaturation, and then equilibrated to aw levels between 0.19±0.03 and 0.54±0.02. Water mobility was determined by wide-line proton-NMR. Powders were inoculated with a four-strain cocktail of Salmonella, vacuum-sealed and stored at 21, 36, 50, 60, 70 and 80°C. Survival data was fitted to the log-linear, the Geeraerd-tail, the Weibull, the biphasic-linear and the Baranyi models. The model with the best ability to describe the data over all temperatures, water activities and water mobilities (f(test)activity significantly influenced the survival of Salmonella at all temperatures, survival increasing with decreasing a(w). Water mobility did not significantly influence survival independent of a(w). Secondary models were useful in predicting the survival of Salmonella in various low-moisture foods providing a correlation of R=0.94 and an acceptable prediction performance of 81

  3. Persistent inflation at Aira caldera accompanying explosive activity at Sakurajima volcano: Constraining deformation source parameters from Finite Element inversions

    NASA Astrophysics Data System (ADS)

    Hickey, James; Gottsmann, Jo; Iguchi, Masato; Nakamichi, Haruhisa

    2015-04-01

    Aira caldera is located within Kagoshima Bay at the southern end of Kyushu, Japan. Sakurajima is an active post-caldera andesitic stratovolcano that sits on the caldera's southern rim. Despite frequent Vulcanian-type explosive activity, the area is experiencing continued uplift at a maximum rate of approximately 1.5 cm/yr with a footprint of 40 km, indicating that magma is being supplied faster than it is erupted. This is of particular concern as the amplitude of deformation is approaching the level inferred prior to the 1914 VEI 4 eruption. Using GPS data from 1996 - 2007 we explore causes for the uplift. To solve for the optimum deformation source parameters we use an inverse Finite Element method accounting for three-dimensional material heterogeneity (inferred from seismic tomography) and the surrounding topography of the region. The same inversions are also carried out using Finite Element models that incorporate simplified homogeneous or one-dimensional subsurface material properties, with and without topography. Results from the comparison of the six different models show statistically significant differences in the inferred deformation sources. This indicates that both subsurface heterogeneity and surface topography are essential in geodetic modelling to extract the most realistic deformation source parameters. The current best-fit source sits within a seismic low-velocity zone in the north-east of the caldera at a depth of approximately 14 km with a volume increase of 1.2 x 108 m3. The source location underlies a region of active underwater fumaroles within the Wakamiko crater and differs significantly from previous analytical modelling results. Seismic data further highlights areas of high seismic attenuation as well as large aseismic zones, both of which could allude to inelastic behaviour and a significant heat source at depth. To integrate these observations, subsequent forward Finite Element models will quantify the importance of rheology and

  4. Role of phosphatase activity of soluble epoxide hydrolase in regulating simvastatin-activated endothelial nitric oxide synthase

    PubMed Central

    Hou, Hsin-Han; Liao, Yi-Jen; Hsiao, Sheng-Huang; Shyue, Song-Kun; Lee, Tzong-Shyuan

    2015-01-01

    Soluble epoxide hydrolase (sEH) has C-terminal epoxide hydrolase and N-terminal lipid phosphatase activity. Its hydrolase activity is associated with endothelial nitric oxide synthase (eNOS) dysfunction. However, little is known about the role of sEH phosphatase in regulating eNOS activity. Simvastatin, a clinical lipid-lowering drug, also has a pleiotropic effect on eNOS activation. However, whether sEH phosphatase is involved in simvastatin-activated eNOS activity remains elusive. We investigated the role of sEH phosphatase activity in simvastatin-mediated activation of eNOS in endothelial cells (ECs). Simvastain increased the phosphatase activity of sEH, which was diminished by pharmacological inhibitors of sEH phosphatase. In addition, pharmacological inhibition of sEH phosphatase or overexpressing the inactive phosphatase domain of sEH enhanced simvastatin-induced NO bioavailability, tube formation and phosphorylation of eNOS, Akt, and AMP-activated protein kinase (AMPK). In contrast, overexpressing the phosphatase domain of sEH limited the simvastatin-increased NO biosynthesis and eNOS phosphorylation at Ser1179. Simvastatin evoked epidermal growth factor receptor–c-Src–increased Tyr phosphorylation of sEH and formation of an sEH–Akt–AMPK–eNOS complex, which was abolished by the c-Src kinase inhibitor PP1 or c-Src dominant-negative mutant K298M. These findings suggest that sEH phosphatase activity negatively regulates simvastatin-activated eNOS by impeding the Akt–AMPK–eNOS signaling cascade. PMID:26304753

  5. Role of phosphatase activity of soluble epoxide hydrolase in regulating simvastatin-activated endothelial nitric oxide synthase.

    PubMed

    Hou, Hsin-Han; Liao, Yi-Jen; Hsiao, Sheng-Huang; Shyue, Song-Kun; Lee, Tzong-Shyuan

    2015-08-25

    Soluble epoxide hydrolase (sEH) has C-terminal epoxide hydrolase and N-terminal lipid phosphatase activity. Its hydrolase activity is associated with endothelial nitric oxide synthase (eNOS) dysfunction. However, little is known about the role of sEH phosphatase in regulating eNOS activity. Simvastatin, a clinical lipid-lowering drug, also has a pleiotropic effect on eNOS activation. However, whether sEH phosphatase is involved in simvastatin-activated eNOS activity remains elusive. We investigated the role of sEH phosphatase activity in simvastatin-mediated activation of eNOS in endothelial cells (ECs). Simvastain increased the phosphatase activity of sEH, which was diminished by pharmacological inhibitors of sEH phosphatase. In addition, pharmacological inhibition of sEH phosphatase or overexpressing the inactive phosphatase domain of sEH enhanced simvastatin-induced NO bioavailability, tube formation and phosphorylation of eNOS, Akt, and AMP-activated protein kinase (AMPK). In contrast, overexpressing the phosphatase domain of sEH limited the simvastatin-increased NO biosynthesis and eNOS phosphorylation at Ser1179. Simvastatin evoked epidermal growth factor receptor-c-Src-increased Tyr phosphorylation of sEH and formation of an sEH-Akt-AMPK-eNOS complex, which was abolished by the c-Src kinase inhibitor PP1 or c-Src dominant-negative mutant K298M. These findings suggest that sEH phosphatase activity negatively regulates simvastatin-activated eNOS by impeding the Akt-AMPK-eNOS signaling cascade.

  6. High-order ENO methods for the unsteady compressible Navier-Stokes equations

    NASA Technical Reports Server (NTRS)

    Atkins, H. L.

    1991-01-01

    The adaptive stencil concepts of ENO (Essentially Non-Oscillatory) methods are applied to the laminar Navier-Stokes equations to yield a high-order, time-accurate algorithm with a shock-capturing capability. The method targets problems in the areas of nonlinear acoustics, compressible transition, and turbulence which, due to the presence of shocks or complex geometries, are not easily solved by spectral methods. The present approach has been implemented and tested for the full three-dimensional Navier-Stokes equations in a transformed curvilinear coordinate system. Validation results are presented for a variety of problems which verify the method's accuracy properties and shock capturing capabilities, as well as demonstrate its use as a direct simulation tool.

  7. A membrane-based quantitative carrier test to assess the virucidal activity of disinfectants and persistence of viruses on porous fomites.

    PubMed

    Mocé-Llivina, Laura; Papageorgiou, Georgios T; Jofre, Juan

    2006-07-01

    A membrane-based quantitative carrier test method to assess the virucidal activity of disinfectants and the persistence of viruses on fomites under different environmental conditions is described. The method is based on the inactivation of the virus adsorbed to cellulose ester membranes followed by the direct enumeration of the viruses surviving the treatment without the need of an elution step. The method was suitable for four different human enteroviruses tested. Experiments comparing the infectivity loss of human enteroviruses in suspension or adsorbed to the filters after treatment with chlorine and glutaraldehyde showed that the human enteroviruses tested suffered significantly greater log10 reductions when suspended than when adsorbed. Significant differences in the effect of the disinfectants on the various human enteroviruses tested were also observed. Moreover, the procedure allowed determining the inactivation of viruses on fomites under different environmental conditions. Low temperatures and high relative humidities favored the survival of human enteroviruses. Also, viruses adsorbed to the membranes retained their infectivity frozen at -70 degrees C for more than 1 year, thus providing the possibility of preparing very simple reference materials for testing virucidal activities of antiseptics and disinfectants.

  8. Identification and Function Analysis of enolase Gene NlEno1 from Nilaparvata lugens (Stål) (Hemiptera:Delphacidae)

    PubMed Central

    Wang, Wei-Xia; Li, Kai-Long; Chen, Yang; Lai, Feng-Xiang; Fu, Qiang

    2015-01-01

    The enolase [EC 4.2.1.11] is an essential enzyme in the glycolytic pathway catalyzing the conversion of 2-phosphoglycerate (2-PGE) to phosphoenolpyruvate (PEP). In this study, a full-length cDNA encoding α-enolase was cloned from rice brown planthopper (Nilaparvata lugens) and is provisionally designated as NlEno1. The cDNA sequence of NlEno1 was 1,851 bp with an open reading frame (ORF) of 1,305 bp and encoding 434 amino acids. The deduced protein shares high identity of 80–87% with ENO1-like protein from Hemiptera, Diptera, and Lepidoptera speices. The NlEno1 showed the highest mRNA expression level in hemolymph, followed by fat body, salivary gland, ovaries and egg, and showed trace mRNA levels in testis. The mRNA of NlEno1 showed up-regulated level in virulent N. lugens population Mudgo, IR56 and IR42 when compared with TN1 population. Injection of double-stranded RNA (dsRNA) of NlEno1 into the adults significantly down-regulated the NlEno1 mRNA level along with decreased eggs and offspring. Moreover, injection of NlEno1-dsRNA decreased mRNA level of Vitellogenin (Vg) gene. These results showed that the NlEno1, as a key glycolytic enzyme, may play roles in regulation of fecundity and adaptation of N. lugens to resistant rice varieties. PMID:26056319

  9. Activation of the AMP-Activated Protein Kinase by Eicosapentaenoic Acid (EPA, 20:5 n-3) Improves Endothelial Function In Vivo

    PubMed Central

    Wu, Yong; Zhang, Cheng; Dong, Yunzhou; Wang, Shuangxi; Song, Ping; Viollet, Benoit; Zou, Ming-Hui

    2012-01-01

    The aim of the present study was to test the hypothesis that the cardiovascular-protective effects of eicosapentaenoic acid (EPA) may be due, in part, to its ability to stimulate the AMP-activated protein kinase (AMPK)-induced endothelial nitric oxide synthase (eNOS) activation. The role of AMPK in EPA-induced eNOS phosphorylation was investigated in bovine aortic endothelial cells (BAEC), in mice deficient of either AMPKα1 or AMPKα2, in eNOS knockout (KO) mice, or in Apo-E/AMPKα1 dual KO mice. EPA-treatment of BAEC increased both AMPK-Thr172 phosphorylation and AMPK activity, which was accompanied by increased eNOS phosphorylation, NO release, and upregulation of mitochondrial uncoupling protein-2 (UCP-2). Pharmacologic or genetic inhibition of AMPK abolished EPA-enhanced NO release and eNOS phosphorylation in HUVEC. This effect of EPA was absent in the aortas isolated from either eNOS KO mice or AMPKα1 KO mice fed a high-fat, high-cholesterol (HFHC) diet. EPA via upregulation of UCP-2 activates AMPKα1 resulting in increased eNOS phosphorylation and consequent improvement of endothelial function in vivo. PMID:22532857

  10. Developmental exposure to concentrated ambient ultrafine particulate matter air pollution in mice results in persistent and sex-dependent behavioral neurotoxicity and glial activation.

    PubMed

    Allen, Joshua L; Liu, Xiufang; Weston, Douglas; Prince, Lisa; Oberdörster, Günter; Finkelstein, Jacob N; Johnston, Carl J; Cory-Slechta, Deborah A

    2014-07-01

    The brain appears to be a target of air pollution. This study aimed to further ascertain behavioral and neurobiological mechanisms of our previously observed preference for immediate reward (Allen, J. L., Conrad, K., Oberdorster, G., Johnston, C. J., Sleezer, B., and Cory-Slechta, D. A. (2013). Developmental exposure to concentrated ambient particles and preference for immediate reward in mice. Environ. Health Perspect. 121, 32-38), a phenotype consistent with impulsivity, in mice developmentally exposed to inhaled ultrafine particles. It examined the impact of postnatal and/or adult concentrated ambient ultrafine particles (CAPS) or filtered air on another behavior thought to reflect impulsivity, Fixed interval (FI) schedule-controlled performance, and extended the assessment to learning/memory (novel object recognition (NOR)), and locomotor activity to assist in understanding behavioral mechanisms of action. In addition, levels of brain monoamines and amino acids, and markers of glial presence and activation (GFAP, IBA-1) were assessed in mesocorticolimbic brain regions mediating these cognitive functions. This design produced four treatment groups/sex of postnatal/adult exposure: Air/Air, Air/CAPS, CAPS/Air, and CAPS/CAPS. FI performance was adversely influenced by CAPS/Air in males, but by Air/CAPS in females, effects that appeared to reflect corresponding changes in brain mesocorticolimbic dopamine/glutamate systems that mediate FI performance. Both sexes showed impaired short-term memory on the NOR. Mechanistically, cortical and hippocampal changes in amino acids raised the potential for excitotoxicity, and persistent glial activation was seen in frontal cortex and corpus callosum of both sexes. Collectively, neurodevelopment and/or adulthood CAPS can produce enduring and sex-dependent neurotoxicity. Although mechanisms of these effects remain to be fully elucidated, findings suggest that neurodevelopment and/or adulthood air pollution exposure may represent

  11. Developmental Exposure to Concentrated Ambient Ultrafine Particulate Matter Air Pollution in Mice Results in Persistent and Sex-Dependent Behavioral Neurotoxicity and Glial Activation

    PubMed Central

    Allen, Joshua L.; Liu, Xiufang; Weston, Douglas; Prince, Lisa; Oberdörster, Günter; Finkelstein, Jacob N.; Johnston, Carl J.; Cory-Slechta, Deborah A.

    2014-01-01

    The brain appears to be a target of air pollution. This study aimed to further ascertain behavioral and neurobiological mechanisms of our previously observed preference for immediate reward (Allen, J. L., Conrad, K., Oberdorster, G., Johnston, C. J., Sleezer, B., and Cory-Slechta, D. A. (2013). Developmental exposure to concentrated ambient particles and preference for immediate reward in mice. Environ. Health Perspect. 121, 32–38), a phenotype consistent with impulsivity, in mice developmentally exposed to inhaled ultrafine particles. It examined the impact of postnatal and/or adult concentrated ambient ultrafine particles (CAPS) or filtered air on another behavior thought to reflect impulsivity, Fixed interval (FI) schedule-controlled performance, and extended the assessment to learning/memory (novel object recognition (NOR)), and locomotor activity to assist in understanding behavioral mechanisms of action. In addition, levels of brain monoamines and amino acids, and markers of glial presence and activation (GFAP, IBA-1) were assessed in mesocorticolimbic brain regions mediating these cognitive functions. This design produced four treatment groups/sex of postnatal/adult exposure: Air/Air, Air/CAPS, CAPS/Air, and CAPS/CAPS. FI performance was adversely influenced by CAPS/Air in males, but by Air/CAPS in females, effects that appeared to reflect corresponding changes in brain mesocorticolimbic dopamine/glutamate systems that mediate FI performance. Both sexes showed impaired short-term memory on the NOR. Mechanistically, cortical and hippocampal changes in amino acids raised the potential for excitotoxicity, and persistent glial activation was seen in frontal cortex and corpus callosum of both sexes. Collectively, neurodevelopment and/or adulthood CAPS can produce enduring and sex-dependent neurotoxicity. Although mechanisms of these effects remain to be fully elucidated, findings suggest that neurodevelopment and/or adulthood air pollution exposure may

  12. Immune reconstitution but persistent activation after 48 weeks of antiretroviral therapy in youth with pre-therapy CD4 >350 in ATN 061

    PubMed Central

    Rudy, Bret J.; Kapogiannis, Bill G.; Worrell, Carol; Squires, Kathleen; Bethel, James; Li, Su; Wilson, Craig M.; Agwu, Allison; Emmanuel, Patricia; Price, Georgine; Hudey, Stephanie; Goodenow, Maureen M.; Sleasman, John W.

    2015-01-01

    Measures of immune outcomes in youth who initiate combination antiretroviral therapy (cART) early in HIV infection are limited. Design Adolescent Trials Network 061 examined changes over 48 weeks of cART in T cell subsets and markers of T cell and macrophage activation in subjects with pre-therapy CD4>350. All subjects had optimal viral suppression from weeks 24 through 48. Methods Subjects (n=48) initiated cART with tenofovir/emtricitabine plus ritonavir-boosted atazanavir. Data were collected at baseline and weeks 12, 24, and 48. Trends were compared to uninfected controls. Results Significant increases over 48 weeks were noted in all CD4 populations including total, naïve, central memory (CM), and effector memory RO (EM RO) and effector memory RA (EM RA) while numbers of CM and EMRO CD8 cells declined significantly. By week 48, CD4 naïve cells were similar to controls while CM CD4 cells remained significantly lower and EM RO and EM RA subsets were significantly higher. CD38 and HLA DR expression, both individually and when co-expressed, decreased over 48 weeks of cART on CD8 cells but remained significantly higher than controls at week 48. In contrast, markers of macrophage activation measured by sCD14 and sCD163 in plasma did not change with cART and were significantly higher than controls. Conclusion In youth initiating early cART, CD4 cell reconstitution is robust with decreases in CD8 cells. However CD8 T cell and macrophage activation persists at higher levels than uninfected controls. PMID:25942459

  13. CRISPR/gRNA-directed synergistic activation mediator (SAM) induces specific, persistent and robust reactivation of the HIV-1 latent reservoirs

    PubMed Central

    Zhang, Yonggang; Yin, Chaoran; Zhang, Ting; Li, Fang; Yang, Wensheng; Kaminski, Rafal; Fagan, Philip Regis; Putatunda, Raj; Young, Won-Bin; Khalili, Kamel; Hu, Wenhui

    2015-01-01

    Current antiretroviral therapy does not eliminate the integrated and transcriptionally silent HIV-1 provirus in latently infected cells. Recently, a “shock and kill” strategy has been extensively explored to eradicate the HIV-1 latent reservoirs for a permanent cure of AIDS. The therapeutic efficacy of currently used agents remains disappointing because of low efficiency, non-specificity and cellular toxicity. Here we present a novel catalytically-deficient Cas9-synergistic activation mediator (dCas9-SAM) technology to selectively, potently and persistently reactivate the HIV-1 latent reservoirs. By screening 16 MS2-mediated single guide RNAs, we identified long terminal repeat (LTR)-L and O that surround the enhancer region (-165/-145 for L and -92/-112 for O) and induce robust reactivation of HIV-1 provirus in HIV-1 latent TZM-bI epithelial, Jurkat T lymphocytic and CHME5 microglial cells. This compulsory reactivation induced cellular suicide via toxic buildup of viral proteins within HIV-1 latent Jurkat T and CHME5 microglial cells. These results suggest that this highly effective and target-specific dCas9-SAM system can serve as a novel HIV-latency-reversing therapeutic tool for the permanent elimination of HIV-1 latent reservoirs. PMID:26538064

  14. Persisting impact of historical mining activity to metal (Pb, Zn, Cd, Tl, Hg) and metalloid (As, Sb) enrichment in sediments of the Gardon River, Southern France.

    PubMed

    Resongles, Eléonore; Casiot, Corinne; Freydier, Rémi; Dezileau, Laurent; Viers, Jérôme; Elbaz-Poulichet, Françoise

    2014-05-15

    In this study, we assessed past and present influence of ancient mining activity on metal(loid) enrichment in sediments of a former mining watershed (Gardon River, SE France), that is now industrialized and urbanized. A sedimentary archive and current sediments were characterized combining geochemical analyses, zinc isotopic analyses and sequential extractions. The archive was used to establish local geochemical background and recorded (i) increasing enrichment factors (EFs) for Pb, Zn, Cd, Tl, Hg, As and Sb throughout the industrial era, (ii) a contamination peak in 1976 attributed to a tailings dam failure, and (iii) current levels in 2002 and 2011 similar to those of 1969, except for Sb and Hg, reflecting a persisting contamination pattern. Inter-element relationships and spatial distribution of EF values of current sediments throughout the watershed suggested that both ancient and current contamination had a common origin for Pb, Zn, Cd, Tl and As related to the exploitation of Pb/Zn mineralization while old Sb mines and coal extraction area were the main sources for Sb and Hg respectively. This prevailing mining origin was reflected for Zn by a relatively uniform isotopic composition at δ(66)Zn=0.23 ± 0.03‰, although slight decrease from 0.23‰ to 0.18‰ was recorded from upstream to downstream sites along the river course in relation with the contribution of the lighter δ(66)Zn signature (~0.08‰) of acid mine drainage impacted tributaries. Results from sequential extractions revealed that the potential mobility of the studied metal(loid)s varied in the order Sbactivity still contributes to metal enrichment in the sediments of the Gardon River and that some of these metals may be mobilized toward the water compartment.

  15. Increased Brain Perfusion Persists over the First Month of Life in Term Asphyxiated Newborns Treated with Hypothermia: Does it Reflect Activated Angiogenesis?

    PubMed

    Shaikh, Henna; Lechpammer, Mirna; Jensen, Frances E; Warfield, Simon K; Hansen, Anne H; Kosaras, Bela; Shevell, Michael; Wintermark, Pia

    2015-06-01

    Many asphyxiated newborns still develop brain injury despite hypothermia therapy. The development of brain injury in these newborns has been related partly to brain perfusion abnormalities. The purposes of this study were to assess brain hyperperfusion over the first month of life in term asphyxiated newborns and to search for some histopathological clues indicating whether this hyperperfusion may be related to activated angiogenesis following asphyxia. In this prospective cohort study, regional cerebral blood flow was measured in term asphyxiated newborns treated with hypothermia around day 10 of life and around 1 month of life using magnetic resonance imaging (MRI) and arterial spin labeling. A total of 32 MRI scans were obtained from 24 term newborns. Asphyxiated newborns treated with hypothermia displayed an increased cerebral blood flow in the injured brain areas around day 10 of life and up to 1 month of life. In addition, we looked at the histopathological clues in a human asphyxiated newborn and in a rat model of neonatal encephalopathy. Vascular endothelial growth factor (VEGF) was expressed in the injured brain of an asphyxiated newborn treated with hypothermia in the first days of life and of rat pups 24-48 h after the hypoxic-ischemic event, and the endothelial cell count increased in the injured cortex of the pups 7 and 11 days after hypoxia-ischemia. Our data showed that the hyperperfusion measured by imaging persisted in the injured areas up to 1 month of life and that angiogenesis was activated in the injured brain of asphyxiated newborns. PMID:25620793

  16. Weight loss in obese mice persistently infected with lymphocytic choriomeningitis virus is not associated with elevated tumor necrosis factor/cachectin activity in peritoneal macrophages.

    PubMed Central

    Lathey, J. L.; Oldstone, M. B.

    1988-01-01

    C57BL/6 ob/ob (C57 ob/ob) mice infected persistently with lymphocytic choriomeningitis virus (LCMV) show cachexia as judged by a weight loss of greater than 20%. Virus persists in a subset of macrophages. Because a cachexic state occurs in several chronic debilitating diseases of humans, often accompanied by persistent microbial infections with macrophage/monocytic involvement and tumor necrosis factor (TNF) cachectin production, the role of TNF in the weightloss of ob/ob mice infected persistently with LCMV was investigated. TNF mRNA expression was not increased in peritoneal cells from such persistently-infected mice, nor did their serum levels of TNF rise above those in uninfected litter-mates. Furthermore, in vitro LCMV infection of adherent peritoneal cells from these C57 ob/ob mice did not enhance TNF mRNA or protein expression. Therefore, the cachexia-like weight loss observed in C57 ob/ob mice during a persistent LCMV infection is apparently not associated with a measurable increase in TNF. Images Figure 2 Figure 3 Figure 4 PMID:3414785

  17. Human Cytomegalovirus Persistence

    PubMed Central

    Goodrum, Felicia; Caviness, Katie; Zagallo, Patricia

    2012-01-01

    Summary Viral persistence is the rule following infection with all herpesviruses. The β-herpesvirus, human cytomegalovirus (HCMV), persists through chronic and latent states of infection. Both the chronic and latent states of infection contribute to HCMV persistence and to the high HCMV seroprevalence worldwide. The chronic infection is poorly defined molecularly, but clinically manifests as low-level virus shedding over extended periods of time and often in the absence of symptoms. Latency requires long-term maintenance of viral genomes in a reversibly quiescent state in the immunocompetent host. In this review, we focus on recent advances in the biology of HCMV persistence, particularly with respect to the latent mode of persistence. Latently infected individuals harbor HCMV genomes in hematopoietic cells and maintain large subsets of HCMV-specific T-cells. In the last few years, impressive advances have been made in understanding virus-host interactions important to HCMV infection, many of which will profoundly impact latency and persistence. We discuss these advances and their known or potential impact on viral latency. As herpesviruses are met with similar challenges in achieving latency and often employ conserved strategies to persist, we discuss current and future directions of HCMV persistence in the context of the greater body of knowledge regarding α-and γ-herpesviruses persistence. PMID:22329758

  18. eNOS Glu298Asp Polymorphism and Endothelial Dysfunction in Patients with and without End-stage Renal Disease

    PubMed Central

    İlhan, Nevin; Ateş, Kadir; İlhan, Necip; Kaman, Dilara; Çeliker, Hüseyin

    2016-01-01

    Background: Chronic kidney diseases are known to influence nitric oxide metabolites (NOx) and asymmetric dimethylarginine (ADMA), though the exact mechanism is still poorly understood. Aims: The purpose of the present study was to examine eNOS Glu298Asp gene polymorphism, plasma NOx and ADMA concentration in subjects with and without End-stage Renal Disease. Study Design: Case-control study. Methods: In this study, genotype distributions of Glu-298Asp in exon 7 of the eNOS gene polymorphisms in 130 hemodialysis and 64 peritoneal dialysis patients were compared with 92 controls. NOx was measured by using the Griess reaction while arginine, ADMA and SDMA measurements were performed by HPLC. Genotyping for eNOS Glu298Asp polymorphism was detected with the polymerase chain reaction and/or polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique. Results: When the genotype frequencies of TT and GT genes were compared between both groups, there was no detected statistically important difference, even-though a TT genotype frequency was 27 (20.8%) versus 17 (26.6%), GT heterozygote genotype frequency was 52 (40%) versus 22 (34.4%), and GG homozygote genotype frequency was 51 (39.2%) versus 25 (39.1%), respectively (p>0.05). NOx, SDMA and ADMA concentrations were significantly elevated in subjects with hemodialysis patients as compared to their corresponding controls. Whereas nitrite was found to be significantly decreased in the patient with peritoneal dialysis. Conclusion: Not observed any connection between the Glu298Asp polymorphism in the eNOS gene and end-stage Renal Diseases in our study population under different dialysis treatments. However, higher ADMA and SDMA concentrations in subjects with ESRD support the existing hypothesis that NOx overproduction affects endothelial dysfunction. Thus, the reduction of ADMA and SDMA concentrations might play a protective role in ESRD patients. PMID:27403380

  19. Is the biofilm formation and slime producing ability of coagulase-negative staphylococci associated with the persistence and severity of intramammary infection?

    PubMed

    Simojoki, H; Hyvönen, P; Plumed Ferrer, C; Taponen, S; Pyörälä, S

    2012-08-17

    Biofilm and slime formation assists bacteria in avoiding the host immune defence and antimicrobial therapy. It is suspected to affect the severity or persistence of mastitis caused by coagulase-negative staphylococci (CNS), which are a common cause of bovine mastitis. The phenotypic biofilm formation ability of 244 CNS isolates (199 isolates from bovine mastitis and 52 type and reference strains) was investigated with a tissue culture plate (TCP) assay and fluorescent in situ hybridization (FISH). Slime production of the strains was assessed using Congo red agar (CRA) plates. Additionally, genes encoding the adhesion proteins MSCRAMM (microbial surface components recognizing adhesive matrix molecules) and biofilm-associated proteins (bap) were detected. The severity of intramammary infection (IMI) in mastitis from which the isolates originated was measured with milk N-acetyl-β-D-glucosaminidase (NAGase) activity. One-third of isolates from mastitis produced biofilm when analysed with TCP or FISH. The kappa test value, measuring the agreement between two tests, differed between CNS species. Slime production was less frequent for isolates of the common mastitis species Staphylococcus chromogenes (0.2% of isolates produced slime) and Staphylococcus simulans (3.5%) compared to Staphylococcus epidermidis (40%). No association was found between the phenotypic ability to form biofilm and the persistence of IMI or severity of mastitis. Slime production was rare in isolates originating from IMI. Only 12.7% of isolates from persistent IMI and 1.8% of isolates from spontaneously eliminated IMI produced slime. The eno gene encoding laminin-binding protein was most frequently detected among the isolates from mastitis, 75% of them having this gene. Only a few other MSCRAMM genes were detected.

  20. Is the biofilm formation and slime producing ability of coagulase-negative staphylococci associated with the persistence and severity of intramammary infection?

    PubMed

    Simojoki, H; Hyvönen, P; Plumed Ferrer, C; Taponen, S; Pyörälä, S

    2012-08-17

    Biofilm and slime formation assists bacteria in avoiding the host immune defence and antimicrobial therapy. It is suspected to affect the severity or persistence of mastitis caused by coagulase-negative staphylococci (CNS), which are a common cause of bovine mastitis. The phenotypic biofilm formation ability of 244 CNS isolates (199 isolates from bovine mastitis and 52 type and reference strains) was investigated with a tissue culture plate (TCP) assay and fluorescent in situ hybridization (FISH). Slime production of the strains was assessed using Congo red agar (CRA) plates. Additionally, genes encoding the adhesion proteins MSCRAMM (microbial surface components recognizing adhesive matrix molecules) and biofilm-associated proteins (bap) were detected. The severity of intramammary infection (IMI) in mastitis from which the isolates originated was measured with milk N-acetyl-β-D-glucosaminidase (NAGase) activity. One-third of isolates from mastitis produced biofilm when analysed with TCP or FISH. The kappa test value, measuring the agreement between two tests, differed between CNS species. Slime production was less frequent for isolates of the common mastitis species Staphylococcus chromogenes (0.2% of isolates produced slime) and Staphylococcus simulans (3.5%) compared to Staphylococcus epidermidis (40%). No association was found between the phenotypic ability to form biofilm and the persistence of IMI or severity of mastitis. Slime production was rare in isolates originating from IMI. Only 12.7% of isolates from persistent IMI and 1.8% of isolates from spontaneously eliminated IMI produced slime. The eno gene encoding laminin-binding protein was most frequently detected among the isolates from mastitis, 75% of them having this gene. Only a few other MSCRAMM genes were detected. PMID:22424866

  1. RNase G-dependent degradation of the eno mRNA encoding a glycolysis enzyme enolase in Escherichia coli.

    PubMed

    Kaga, Naoko; Umitsuki, Genryou; Nagai, Kazuo; Wachi, Masaaki

    2002-10-01

    Escherichia coli RNase G, encoded by the rng gene, is involved in the processing of 16S rRNA and degradation of the adhE mRNA encoding a fermentative alcohol dehydrogenase. In a search for the intracellular target RNAs of RNase G other than the 16S rRNA precursor and adhE mRNA, total cellular proteins from rng+ and rng::cat cells were compared by two-dimensional gel electrophoresis. The amount of enolase encoded by the eno gene reproducibly increased two- to three-fold in the rng::cat mutant strain compared with the rng+ parent strain. Rifampicin chase experiments showed that the half-life of the eno mRNA was some 3 times longer in the rng::cat mutant than in the wild type. These results indicate that the eno mRNA was a substrate of RNase G in vivo, in addition to 16S rRNA precursor and adhE mRNA. PMID:12450135

  2. VEGF, eNOS, and ABCB1 genetic polymorphisms may increase the risk of osteonecrosis of the femoral head.

    PubMed

    Zhou, Z C; Gu, S Z; Wu, J; Liang, Q W

    2015-01-01

    We investigated the associations between vascular endothelial growth factors (VEGF), endothelial nitric oxide synthase (eNOS), and ATP-binding cassette subfamily B member 1 transporter (ABCB1) polymorphisms and the risk of osteonecrosis of the femoral head (ONFH). Published studies were reviewed and analyzed based on predefined selection criteria. The strength of the association between VEGF, eNOS, and ABCB1 polymorphisms and ONFH risk was evaluated based on the odds ratio with corresponding 95%CIs. Meta-analysis was performed using the Comprehensive Meta-analysis 2.0 software. A total of 135 relevant articles were retrieved, of which 10 studies met the selection criteria, and included a total of 1025 patients with ONFH and 1730 healthy controls. The meta-analysis study results revealed that the VEGF rs2010963 G>C polymorphism increased the risk of ONFH, while the VEGF rs2010963 G>C and ABCB1 rs1045642 C>T polymorphisms increased the risk of ONFH under the allele model. In conclusion, the VEGF, eNOS, and ABCB1 polymorphisms may contribute to ONFH, but further studies including larger sample sizes are needed to confirm the results. PMID:26535684

  3. Association of endothelial nitric oxide synthase (eNOS) gene G894T polymorphism with hypertension risk and complications.

    PubMed

    ALrefai, Abeer A; Habib, Mona Salah El-Din; Yaseen, Rehab I; Gabr, Mahmoud K; Habeeb, Rabab M

    2016-10-01

    This study evaluated the association of NOS3 polymorphisms with hypertension risk and complications. eNOS (G894T) SNP was performed by RT-PCR on 70 hypertensive patients (25 were hypertensive, 25 were hypertensive with CAD, and 20 were diabetic with hypertension) and 30 age- and gender-matched individuals. Lipid and glucose profile were assessed by standard colorimetric assay. Our results revealed that combination of (GT + TT) genotype and T allele significantly increases the risk of hypertension (OR = 3.86 and 4.33), respectively. Subgroup analysis showed significant association between CAD with eNOS (G894T) mutant genotype (P = 0.002) and allele frequency (P < 0.001). Moreover, the mutant homozygous and heterozygous eNOS genotype together were significantly associated with higher TC, LDLc, (P < 0.001), and TG (P = 0.001). Thus, hypercholesterolemia (P < 0.001 and OR = 12.48) increases the risk of hypertension among T carrier. These results indicated that the T carriers significantly increase hypertension risk and complication (CAD), mainly with hypercholesterolemia and in elderly. PMID:27557897

  4. Polymorphisms in endothelial nitric oxide synthase (eNOS) and vascular endothelial growth factor (VEGF) predict sunitinib-induced hypertension.

    PubMed

    Eechoute, K; van der Veldt, A A M; Oosting, S; Kappers, M H W; Wessels, J A M; Gelderblom, H; Guchelaar, H-J; Reyners, A K L; van Herpen, C M L; Haanen, J B; Mathijssen, R H J; Boven, E

    2012-10-01

    Hypertension is an important side effect of sunitinib treatment. In a retrospective study in 255 patients, single-nucleotide polymorphisms (SNPs) in vascular endothelial growth factor A (VEGFA), vascular endothelial growth factor receptor (VEGFR)-2, endothelin-1 (ET-1), and endothelium-derived nitric oxide synthase (eNOS) were multivariately tested against hypertension grades and changes in systolic blood pressure (SBP), diastolic BP (DBP), and mean arterial BP (MAP). Next, the association between hypertension and survival in patients with metastatic renal cell cancer (mRCC) was studied. Greater elevations in SBP and MAP were associated with the presence of a haplotype in VEGFA (P = 0.014 and P = 0.036, respectively). The tendency to develop grade 3 hypertension was associated with this haplotype and also with a SNP in eNOS (P = 0.031 and P = 0.045, respectively). In mRCC patients, sunitinib-induced hypertension was found to confer a survival benefit, with the mean overall survival being prolonged by 7.2 months (P = 0.035 and P = 0.026 for SBP and DBP elevations, respectively). Genetic polymorphisms in VEGFA and eNOS independently predict rise in BP and/or development of severe hypertension in sunitinib-treated patients. Grade 3 hypertension was found to be an independent factor for overall survival in patients with mRCC. PMID:22948895

  5. The Adherent/Invasive Escherichia coli Strain LF82 Invades and Persists in Human Prostate Cell Line RWPE-1, Activating a Strong Inflammatory Response

    PubMed Central

    Aleandri, Marta; Marazzato, Massimiliano; Conte, Antonietta L.; Ambrosi, Cecilia; Nicoletti, Mauro; Zagaglia, Carlo; Gambara, Guido; Palombi, Fioretta; De Cesaris, Paola; Ziparo, Elio; Palamara, Anna T.; Riccioli, Anna

    2016-01-01

    Adherent/invasive Escherichia coli (AIEC) strains have recently been receiving increased attention because they are more prevalent and persistent in the intestine of Crohn's disease (CD) patients than in healthy subjects. Since AIEC strains show a high percentage of similarity to extraintestinal pathogenic E. coli (ExPEC), neonatal meningitis-associated E. coli (NMEC), and uropathogenic E. coli (UPEC) strains, here we compared AIEC strain LF82 with a UPEC isolate (strain EC73) to assess whether LF82 would be able to infect prostate cells as an extraintestinal target. The virulence phenotypes of both strains were determined by using the RWPE-1 prostate cell line. The results obtained indicated that LF82 and EC73 are able to adhere to, invade, and survive within prostate epithelial cells. Invasion was confirmed by immunofluorescence and electron microscopy. Moreover, cytochalasin D and colchicine strongly inhibited bacterial uptake of both strains, indicating the involvement of actin microfilaments and microtubules in host cell invasion. Moreover, both strains belong to phylogenetic group B2 and are strong biofilm producers. In silico analysis reveals that LF82 shares with UPEC strains several virulence factors: namely, type 1 pili, the group II capsule, the vacuolating autotransporter toxin, four iron uptake systems, and the pathogenic island (PAI). Furthermore, compared to EC73, LF82 induces in RWPE-1 cells a marked increase of phosphorylation of mitogen-activated protein kinases (MAPKs) and of NF-κB already by 5 min postinfection, thus inducing a strong inflammatory response. Our in vitro data support the hypothesis that AIEC strains might play a role in prostatitis, and, by exploiting host-cell signaling pathways controlling the innate immune response, likely facilitate bacterial multiplication and dissemination within the male genitourinary tract. PMID:27600504

  6. Infection with the Persistent Murine Norovirus Strain MNV-S99 Suppresses IFN-Beta Release and Activation of Stat1 In Vitro

    PubMed Central

    Niendorf, Sandra; Klemm, Uwe; Mas Marques, Andreas; Bock, C.-Thomas; Höhne, Marina

    2016-01-01

    Norovirus infection is the main cause of epidemic non-bacterial gastroenteritis in humans. Although human norovirus (HuNoV) infection is self-limiting, it can persist for extended periods of time in immune deficient patients. Due to the lack of robust cell culture and small animal systems, little is known about HuNoV pathogenicity. However, murine norovirus (MNV) can be propagated in cell culture and is used as a model to study norovirus infection. Several MNV are known to persist in mice. In this study, we show that the MNV strain MNV-S99 persists in wild type inbred (C57BL/6J) mice over a period of at least 5 weeks post infection. Viral RNA was detectable in the jejunum, ileum, cecum, and colon, with the highest titers in the colon and cecum. To characterize the effect of MNV-S99 on the innate immune response, Stat1 phosphorylation and IFN-β production were analyzed and compared to the non-persistent strain MNV-1.CW3. While MNV-S99 and MNV-1.CW3 showed comparable growth characteristics in vitro, Stat1 phosphorylation and IFN-β release is strongly decreased after infection with MNV-S99 compared to MNV-1.CW3. In conclusion, our results show that unlike MNV-1.CW3, MNV-S99 establishes a persistent infection in mice, possibly due to interfering with the innate immune response. PMID:27294868

  7. Involvement of AMPK, IKβα-NFκB and eNOS in the sildenafil anti-inflammatory mechanism in a demyelination model.

    PubMed

    Nunes, Ana Karolina Santana; Rapôso, Catarina; Rocha, Sura Wanessa Santos; Barbosa, Karla Patrícia de Sousa; Luna, Rayana Leal de Almeida; da Cruz-Höfling, Maria Alice; Peixoto, Christina Alves

    2015-11-19

    Sildenafil (Viagra®) has recently been found to have a neuroprotective effect, which occurs through the inhibition of inflammation and demyelination in the cerebellum. However, the mechanism of action of sildenafil remains unknown. AMPK, the regulatory protein of the lipid and glucose metabolism, plays a protective role by activating the eNOS enzyme. The production of a nanomolar concentration of NO by eNOS has an anti-inflammatory effect through the cGMP signaling pathway and plays an important role in the regulation of the nuclear transcription factor (NFkB), preventing the expression of inflammatory genes. The present study investigated whether AMPK-eNOS-NO-cGMP-IКβα-NFkB is involved in the mechanism of action of sildenafil in a cuprizone-demyelination model. Neuroinflammation and demyelination induced by cuprizone in rodents have been widely used as a model of MS. In the present study, five male C57BL/6 mice (7-10 weeks old) were used. Over a four week period, the groups received: cuprizone (CPZ) 0.2% mixed in feed; CPZ in the diet, combined with the administration of sildenafil (Viagra®, Pfizer, 25mg/kg) orally in drinking water, starting concurrently (sild-T0) or 15 days (sild-T15) after the start of CPZ. Control animals received pure food and water. The cerebella of the mice were dissected and processed for immunohistochemistry, immunofluorescence (frozen), western blotting and dosage of cytokines (Elisa). CPZ induced an increase in the expression of GFAP, IL-1β TNF-α, total NFkB and inactive AMPK, and prompt microglia activation. CPZ also induced a reduction of IKβα. The administration of sildenafil reduced the expression of the pro-inflammatory cytokines IL-1β and TNF-α and increased the expression of the anti-inflammatory cytokine IL-10. In addition, the administration of sildenafil reduced expression of GFAP, NFkB, inactive AMPK and iNOS, and increased IKβα. Interestingly, sildenafil also reduced levels of NGF. In general, the sild-T0 group

  8. Soluble alpha-enolase activates monocytes by CD14-dependent TLR4 signalling pathway and exhibits a dual function

    PubMed Central

    Guillou, Clément; Fréret, Manuel; Fondard, Emeline; Derambure, Céline; Avenel, Gilles; Golinski, Marie-Laure; Verdet, Mathieu; Boyer, Olivier; Caillot, Frédérique; Musette, Philippe; Lequerré, Thierry; Vittecoq, Olivier

    2016-01-01

    Rheumatoid arthritis (RA) is the most common form of chronic inflammatory rheumatism. Identifying auto-antigens targeted by RA auto-antibodies is of major interest. Alpha-enolase (ENO1) is considered to be a pivotal auto-antigen in early RA but its pathophysiologic role remains unknown. The main objective of this study was to investigate the in vitro effects of soluble ENO1 on peripheral blood mononuclear cells (PBMC) from healthy donors and RA patients in order to determine the potential pathogenic role of ENO1. ELISA, transcriptomic analysis, experiments of receptor inhibition and flow cytometry analysis were performed to determine the effect, the target cell population and the receptor of ENO1. We showed that ENO1 has the ability to induce early production of pro-inflammatory cytokines and chemokines with delayed production of IL-10 and to activate the innate immune system. We demonstrated that ENO1 binds mainly to monocytes and activates the CD14-dependent TLR4 pathway both in healthy subjects and in RA patients. Our results establish for the first time that ENO1 is able to activate in vitro the CD14-dependent TLR4 pathway on monocytes involving a dual mechanism firstly pro-inflammatory and secondly anti-inflammatory. These results contribute to elucidating the role of this auto-antigen in the pathophysiologic mechanisms of RA. PMID:27025255

  9. Isolated persistent hypermethioninemia.

    PubMed Central

    Mudd, S H; Levy, H L; Tangerman, A; Boujet, C; Buist, N; Davidson-Mundt, A; Hudgins, L; Oyanagi, K; Nagao, M; Wilson, W G

    1995-01-01

    New information has been obtained on 30 patients with isolated persistent hypermethioninemia, most of them previously unreported. Biopsies to confirm the presumptive diagnosis of partially deficient activity of ATP: L-methionine S-adenosyltransferase (MAT; E.C.2.5.1.6) in liver were not performed on most of these patients. However, none showed the clinical findings or the extreme elevations of serum folate previously described in other patients with isolated hypermethioninemia considered not to have hepatic MAT deficiency. Patients ascertained on biochemical grounds had no neurological abnormalities, and 27/30 had IQs or Bayley development-index scores within normal limits or were judged to have normal mental development. Methionine transamination metabolites accumulated abnormally only when plasma methionine concentrations exceeded 300-350 microM and did so more markedly after 0.9 years of age. Data were obtained on urinary organic acids as well as plasma creatinine concentrations. Patterns of inheritance of isolated hypermethioninemia were variable. Considerations as to the optimal management of this group of patients are discussed. PMID:7573050

  10. Glyphosate persistence in seawater.

    PubMed

    Mercurio, Philip; Flores, Florita; Mueller, Jochen F; Carter, Steve; Negri, Andrew P

    2014-08-30

    Glyphosate is one of the most widely applied herbicides globally but its persistence in seawater has not been reported. Here we quantify the biodegradation of glyphosate using standard "simulation" flask tests with native bacterial populations and coastal seawater from the Great Barrier Reef. The half-life for glyphosate at 25 °C in low-light was 47 days, extending to 267 days in the dark at 25 °C and 315 days in the dark at 31 °C, which is the longest persistence reported for this herbicide. AMPA, the microbial transformation product of glyphosate, was detected under all conditions, confirming that degradation was mediated by the native microbial community. This study demonstrates glyphosate is moderately persistent in the marine water under low light conditions and is highly persistent in the dark. Little degradation would be expected during flood plumes in the tropics, which could potentially deliver dissolved and sediment-bound glyphosate far from shore.

  11. Persistent heap Management library

    SciTech Connect

    2012-01-17

    PERM is a C library for persistent heap management and is intended for use with a dynamic-memory allocator (e.g. malloc, free). The PERM memory allocator replaces the standard C dynamic memory allocation functions with compatible versions that provide persistent memory to application programs. Memory allocated with the PERM allocatory will persist between program invocations after a call to a checkpoint function. This function essentially saves the state of the heap and registered global variables to a file which may reside in flash memory or other node local storage. A few other functions are also provided by the library to manage checkpoint files. Global variables in an application can be marked persistent and be included in a checkpoint by using a compiler attribute defined as PERM. The PERM checkpoint methof is not dependent on the programming model ans works with distributed memory or shared memory programs.

  12. Persistent depressive disorder

    MedlinePlus

    PDD; Chronic depression; Depression - chronic ... The exact cause of persistent depressive disorder (PDD) is unknown. It tends to run in families. PDD occurs more often in women. Most people with PDD will also ...

  13. Persistent heap Management library

    2012-01-17

    PERM is a C library for persistent heap management and is intended for use with a dynamic-memory allocator (e.g. malloc, free). The PERM memory allocator replaces the standard C dynamic memory allocation functions with compatible versions that provide persistent memory to application programs. Memory allocated with the PERM allocatory will persist between program invocations after a call to a checkpoint function. This function essentially saves the state of the heap and registered global variables tomore » a file which may reside in flash memory or other node local storage. A few other functions are also provided by the library to manage checkpoint files. Global variables in an application can be marked persistent and be included in a checkpoint by using a compiler attribute defined as PERM. The PERM checkpoint methof is not dependent on the programming model ans works with distributed memory or shared memory programs.« less

  14. Persistent Structural Priming from Language Comprehension to Language Production

    ERIC Educational Resources Information Center

    Bock, Kathryn; Dell, Gary S.; Chang, Franklin; Onishi, Kristine H.

    2007-01-01

    To examine the relationship between syntactic processes in language comprehension and language production, we compared structural persistence from sentence primes that speakers heard to persistence from primes that speakers produced. [Bock, J. K., & Griffin, Z. M. (2000). The persistence of structural priming: transient activation or implicit…

  15. A connecting hinge represses the activity of endothelial nitric oxide synthase.

    PubMed

    Haque, Mohammad Mahfuzul; Panda, Koustubh; Tejero, Jesús; Aulak, Kulwant S; Fadlalla, Mohammed Adam; Mustovich, Anthony T; Stuehr, Dennis J

    2007-05-29

    In mammals, endothelial nitric oxide synthase (eNOS) has the weakest activity, being one-tenth and one-sixth as active as the inducible NOS (iNOS) and the neuronal NOS (nNOS), respectively. The basis for this weak activity is unclear. We hypothesized that a hinge element that connects the FMN module in the reductase domain but is shorter and of unique composition in eNOS may be involved. To test this hypothesis, we generated an eNOS chimera that contained the nNOS hinge and two mutants that either eliminated (P728IeNOS) or incorporated (I958PnNOS) a proline residue unique to the eNOS hinge. Incorporating the nNOS hinge into eNOS increased NO synthesis activity 4-fold, to an activity two-thirds that of nNOS. It also decreased uncoupled NADPH oxidation, increased the apparent K(m)O(2) for NO synthesis, and caused a faster heme reduction. Eliminating the hinge proline had similar, but lesser, effects. Our findings reveal that the hinge is an important regulator and show that differences in its composition restrict the activity of eNOS relative to other NOS enzymes.

  16. EBV Persistence--Introducing the Virus.

    PubMed

    Thorley-Lawson, David A

    2015-01-01

    Persistent infection by EBV is explained by the germinal center model (GCM) which provides a satisfying and currently the only explanation for EBVs disparate biology. Since the GCM touches on every aspect of the virus, this chapter will serve as an introduction to the subsequent chapters. EBV is B lymphotropic, and its biology closely follows that of normal mature B lymphocytes. The virus persists quiescently in resting memory B cells for the lifetime of the host in a non-pathogenic state that is also invisible to the immune response. To access this compartment, the virus infects naïve B cells in the lymphoepithelium of the tonsils and activates these cells using the growth transcription program. These cells migrate to the GC where they switch to a more limited transcription program, the default program, which helps rescue them into the memory compartment where the virus persists. For egress, the infected memory cells return to the lymphoepithelium where they occasionally differentiate into plasma cells activating viral replication. The released virus can either infect more naïve B cells or be amplified in the epithelium for shedding. This cycle of infection and the quiescent state in memory B cells allow for lifetime persistence at a very low level that is remarkably stable over time. Mathematically, this is a stable fixed point where the mechanisms regulating persistence drive the state back to equilibrium when perturbed. This is the GCM of EBV persistence. Other possible sites and mechanisms of persistence will also be discussed. PMID:26424647

  17. Resveratrol Ameliorates High Glucose and High-Fat/Sucrose Diet-Induced Vascular Hyperpermeability Involving Cav-1/eNOS Regulation

    PubMed Central

    Peng, Xiao lin; Qu, Wei; Wang, Lin zhi; Huang, Bin qing; Ying, Chen jiang; Sun, Xiu fa; Hao, Li ping

    2014-01-01

    Vascular endothelial hyperpermeability is one of the manifestations of endothelial dysfunction. Resveratrol (Res) is considered to be beneficial in protecting endothelial function. However, currently, the exact protective effect and involved mechanisms of Res on endothelial dysfunction-hyperpermeability have not been completely clarified. The aim of present study is to investigate the effects of Res on amelioration of endothelial hyperpermeability and the role of caveolin-1 (Cav-1)/endothelial nitric oxide synthase (eNOS) pathway. Adult male Wistar rats were treated with a normal or high-fat/sucrose diet (HFS) with or without Res for 13 weeks. HFS and in vitro treatment with high glucose increased hyperpermeability in rat aorta, heart, liver and kidney and cultured bovine aortic endothelial cells (BAECs), respectively, which was attenuated by Res treatment. Application of Res reversed the changes in eNOS and Cav-1 expressions in aorta and heart of rats fed HFS and in BAECs incubated with high glucose. Res stimulated the formation of NO inhibited by high glucose in BAECs. Beta-Cyclodextrin (β-CD), caveolae inhibitor, showed the better beneficial effect than Res alone to up-regulate eNOS phosphorylative levels, while NG-Nitro-77 L-arginine methyl ester (L-NAME), eNOS inhibitor, had no effect on Cav-1 expression. Our studies suggested that HFS and in vitro treatment with high glucose caused endothelial hyperpermeability, which were ameliorated by Res at least involving Cav-1/eNOS regulation. PMID:25419974

  18. Kallistatin inhibits TGF-β-induced endothelial-mesenchymal transition by differential regulation of microRNA-21 and eNOS expression.

    PubMed

    Guo, Youming; Li, Pengfei; Bledsoe, Grant; Yang, Zhi-Rong; Chao, Lee; Chao, Julie

    2015-09-10

    Kallistatin, an endogenous protein, consists of two structural elements: active site and heparin-binding domain. Kallistatin exerts beneficial effects on fibrosis by suppressing transforming growth factor (TGF)-β synthesis in animal models. TGF-β is the most potent inducer of endothelial-mesenchymal transition (EndMT), which contributes to fibrosis and cancer. MicroRNA (miR)-21 is an important player in organ fibrosis and tumor invasion. Here we investigated the potential role of kallistatin in EndMT via modulation of miR-21 in endothelial cells. Human kallistatin treatment blocked TGF-β-induced EndMT, as evidenced by morphological changes as well as increased endothelial and reduced mesenchymal marker expression. Kallistatin also inhibited TGF-β-mediated reactive oxygen species (ROS) formation and NADPH oxidase expression and activity. Moreover, kallistatin antagonized TGF-β-induced miR-21 and Snail1 synthesis, Akt phosphorylation, NF-κB activation, and matrix metalloproteinase 2 (MMP2) synthesis and activation. Kallistatin via its heparin-binding site blocked TGF-β-induced miR-21, Snail1 expression, and ROS formation, as wild-type kallistatin, but not heparin-binding site mutant kallistatin, exerted the effect. Conversely, kallistatin through its active site stimulated the synthesis of endothelial nitric oxide synthase (eNOS), sirtuin 1 (Sirt1) and forkhead box O1 (FoxO1); however, these effects were blocked by genistein, a tyrosine kinase inhibitor. This is the first study to demonstrate that kallistatin's heparin-binding site is crucial for preventing TGF-β-induced miR-21 and oxidative stress, while its active site is key for stimulating the expression of antioxidant genes via interaction with an endothelial surface tyrosine kinase. These findings reveal novel mechanisms of kallistatin in protection against fibrosis and cancer by suppressing EndMT.

  19. Persistent cooperators in nature.

    PubMed

    Liu, Xinsheng; Guo, Wanlin

    2010-12-21

    The evolution and maintenance of cooperation fascinated researchers for several decades. Recently, theoretical models and experimental evidence show that costly punishment may facilitate cooperation in human societies. The puzzle how the costly punishment behaviour evolves can be solved under voluntary participation. Could the punishers emerge if participation is compulsory? Is the punishment inevitably a selfish behaviour or an altruistic behaviour? The motivations behind punishment are still an enigma. Based on public goods interactions, we present a model in which just a certain portion of the public good is divided equally among all members. The other portion is distributed to contributors when paying a second cost. The contributors who are willing to pay a second cost are called the persistent cooperators (PC), indicating their desire to retrieve the proportion of the payoff derived from their own contributions with persistent efforts. We show that the persistent cooperators can be costly punishers, which may account for the origin of human costly punishment behaviour under compulsory participation. In this sense our models may show theoretically that the original motivation behind punishment is to retrieve deserved payoff from their own contributions, a selfish incentive. But the persistent cooperators can also flourish or dominate the population in other situations. We list many real examples in which contributors are the persistent cooperators, and they benefit. This indicates a simple norm promoting cooperation: contributing more and gaining more.

  20. Activation of protease calpain by oxidized and glycated LDL increases the degradation of endothelial nitric oxide synthase

    PubMed Central

    Dong, Yunzhou; Wu, Yong; Wu, Mingyuan; Wang, Shuangxi; Zhang, Junhua; Xie, Zhonglin; Xu, Jian; Song, Ping; Wilson, Kenneth; Zhao, Zhengxing; Lyons, Timothy; Zou, Ming-Hui

    2009-01-01

    Oxidation and glycation of low-density lipoprotein (LDL) promote vascular injury in diabetes; however, the mechanisms underlying this effect remain poorly defined. The present study was conducted to determine the effects of ‘heavily oxidized’ glycated LDL (HOG-LDL) on endothelial nitric oxide synthase (eNOS) function. Exposure of bovine aortic endothelial cells with HOG-LDL reduced eNOS protein levels in a concentration- and time-dependent manner, without altering eNOS mRNA levels. Reduced eNOS protein levels were accompanied by an increase in intracellular Ca2+, augmented production of reactive oxygen species (ROS) and induction of Ca2+-dependent calpain activity. Neither eNOS reduction nor any of these other effects were observed in cells exposed to native LDL. Reduction of intracellular Ca2+ levels abolished eNOS reduction by HOG-LDL, as did pharmacological or genetic through calcium channel blockers or calcium chelator BAPTA or inhibition of NAD(P)H oxidase (with apocynin) or inhibition of calpain (calpain 1-specific siRNA). Consistent with these results, HOG-LDL impaired acetylcholine-induced endothelium-dependent vasorelaxation of isolated mouse aortas, and pharmacological inhibition of calpain prevented this effect. HOG-LDL may impair endothelial function by inducing calpain-mediated eNOS degradation in a ROS- and Ca2+-dependent manner. PMID:18624772

  1. Visual persistence and cinema?

    PubMed

    Galifret, Yves

    2006-01-01

    In Faraday and Plateau's days, both apparent motion and the fusion of intermittent lights, two phenomena that are hardly connected, were explained by retinal persistence. The works of Exner and of the 'Gestalt' psychologists, as well as the modern works on 'sampled' motion and smooth motion, disregarded retinal persistence. One tried, originally, to measure this persistence using intermittent stimulation, but under the pressure of practical concern, what was established in 1902 was the logarithmic relation between fusion frequency and the intensity of the stimulation. One had to wait until the 1950s for the use of harmonic analysis to finally allow a renewal in which many problems that, for decades, had only given rise to discussions that led nowhere and to groundless assertions, were correctly stated and easily solved.

  2. Visual persistence and cinema?

    PubMed

    Galifret, Yves

    2006-01-01

    In Faraday and Plateau's days, both apparent motion and the fusion of intermittent lights, two phenomena that are hardly connected, were explained by retinal persistence. The works of Exner and of the 'Gestalt' psychologists, as well as the modern works on 'sampled' motion and smooth motion, disregarded retinal persistence. One tried, originally, to measure this persistence using intermittent stimulation, but under the pressure of practical concern, what was established in 1902 was the logarithmic relation between fusion frequency and the intensity of the stimulation. One had to wait until the 1950s for the use of harmonic analysis to finally allow a renewal in which many problems that, for decades, had only given rise to discussions that led nowhere and to groundless assertions, were correctly stated and easily solved. PMID:16731495

  3. Microbial persistence and the road to drug resistance

    PubMed Central

    Cohen, Nadia R.; Lobritz, Michael A.; Collins, James J.

    2013-01-01

    Summary Microbial drug persistence is a widespread phenomenon in which a sub-population of microorganisms is able to survive antimicrobial treatment without acquiring resistance-conferring genetic changes. Microbial persisters can cause recurrent or intractable infections, and like resistant mutants, they carry an increasing clinical burden. In contrast to heritable drug resistance, however, the biology of persistence is only beginning to be unraveled. Persisters have traditionally been thought of as metabolically dormant, non-dividing cells. However, as discussed in this review, increasing evidence suggests that persistence is in fact an actively maintained state, triggered and enabled by a network of intracellular stress-responses that can accelerate processes of adaptive evolution. Beyond shedding light on the basis of persistence, these findings raise the possibility that persisters behave as an evolutionary reservoir from which resistant organisms can emerge. As persistence and its consequences come into clearer focus, clinically relevant eradication strategies are urgently needed. PMID:23768488

  4. Evaluation of Protective Immune Responses Induced by Recombinant TrxLp and ENO2 Proteins against Toxoplasma gondii Infection in BALB/c Mice

    PubMed Central

    Wang, Meng; Yang, Xiao-Yu; Zhang, De-Lin

    2016-01-01

    Toxoplasma gondii is an obligate intracellular parasitic protozoan that can infect almost all species of warm-blooded animals. As any chemical-based drugs could not act against the tissue cyst stage of T. gondii, vaccination may be one of the ideal control strategies. In the present study, two new vaccine candidates, named TgENO2 and TgTrxLp, were purified from Escherichia coli with pET-30a(+) expression system and then were injected into BALB/c mice to evaluate the protective efficacy against acute and chronic toxoplasmosis. The results showed that both the recombinant proteins, either alone or in combination, could elicit strong humoral and cellular immune responses with a higher level of IgG antibodies, IFN-γ, IL-2, CD4+, and CD8+ T cells as compared to those in mice from control groups. After acute challenge with tachyzoites of the GJS strain, mice immunized with rTgTrxLp (8 ± 2.77 d), rTgENO2 (7.4 ± 1.81 d), and rTgTrxLp + rTgENO2 (8.38 ± 4.57 d) proteins showed significantly longer survival time than those that received Freund's adjuvant (6.78 ± 2.08 d) and PBS (6.38 ± 4.65 d) (χ2 = 9.687, df = 4, P = 0.046). The protective immunity of rTgTrxLp, rTgENO2, and rTgTrxLp + rTgENO2 proteins against chronic T. gondii infection showed 69.77%, 58.14%, and 20.93% brain cyst reduction as compared to mice that received PBS. The present study suggested that both TgENO2 and TgTrxLp were potential candidates for the development of multicomponent vaccines against toxoplasmosis. PMID:27803923

  5. Role of muscular eNOS in skeletal arteries: Endothelium-independent hypoxic vasoconstriction of the femoral artery is impaired in eNOS-deficient mice.

    PubMed

    Kim, Hae Jin; Yoo, Hae Young; Lin, Hai Yue; Oh, Goo Taeg; Zhang, Yin Hua; Kim, Sung Joon

    2016-09-01

    We previously reported that hypoxia augments α-adrenergic contraction (hypoxic vasoconstriction, HVC) of skeletal arteries in rats. The underlying mechanism may involve hypoxic inhibition of endothelial nitric oxide synthase (eNOS) expressed in skeletal arterial myocytes (16). To further explore the novel role of muscular eNOS in the skeletal artery, we compared HVC in femoral arteries (FAs) from eNOS knockout (KO) mice with that from wild-type (WT) and heterozygous (HZ) mice. Immunohistochemical assays revealed that, in addition to endothelia, eNOS is also expressed in the medial layer of FAs, albeit at a much lower level. However, the medial eNOS signal was not evident in HZ FAs, despite strong expression in the endothelium; similar observations were made in WT carotid arteries (CAs). The amplitude of contraction induced by 1 μM phenylephrine (PhE) was greater in HZ than in WT FAs. Hypoxia (3% Po2) significantly augmented PhE-induced contraction in WT FAs but not in HZ or KO FAs. No HVC was observed in PhE-pretreated WT CAs. The NOS inhibitor nitro-l-arginine methyl ester (0.1 mM) also augmented PhE contraction in endothelium-denuded WT FAs but not in WT CAs. Inhibitors specific to neuronal NOS and inducible NOS did not augment PhE-induced contraction of WT FAs. NADPH oxidase 4 (NOX4) inhibitor (GKT137831, 5 μM), but not NOX2 inhibitor (apocynin, 100 μM), suppressed HVC. Consistent with the role of reactive oxygen species (ROS), HVC was also inhibited by pretreatment with tiron or polyethylene glycol-catalase. Taken together, these data suggest that the eNOS expressed in smooth muscle cells in FAs attenuates α-adrenergic vasoconstriction; this suppression is alleviated under hypoxia, which potentiates vasoconstriction in a NOX4/ROS-dependent mechanism. PMID:27486092

  6. Association of Common Variants in eNOS Gene with Primary Open Angle Glaucoma: A Meta-Analysis.

    PubMed

    Xiang, Yang; Dong, Yi; Li, Xuan; Tang, Xin

    2016-01-01

    Purpose. To clarify the association of endothelial nitric oxide synthase (eNOS) polymorphisms and primary open angle glaucoma (POAG). Methods. After a systematic literature search in the MEDLINE, EMBASE, and ISI Web of Science databases, all relevant studies evaluating the association between the polymorphisms (rs2070744 and rs1799983) of eNOS gene and POAG were screened and included. The pooled odds ratios (ORs) and the 95% confidence interval (CI) of each single-nucleotide polymorphism (SNP) in five genetic models were estimated using fixed-effect model if I (2) < 50% in the test for heterogeneity; otherwise the random-effects model was used. Results. Thirty-one records were obtained, with five being suitable for meta-analysis. The overall results showed that both TT genotype in rs2070744 and GG genotype in rs1799983 are associated with decreased risk of POAG susceptibility. Stratified analysis based on ethnicity showed that the association of rs2070744 with POAG remained only in Caucasians. Results of subgroup analysis by sex indicated association between both polymorphisms and POAG in female group, but not in male group. Conclusions. TT genotype and/or T-allele in rs2070744, as well as GG genotype and/or G-allele in rs1799983, was associated with decreased risk for POAG overall and in female group. PMID:27242919

  7. Association of Common Variants in eNOS Gene with Primary Open Angle Glaucoma: A Meta-Analysis

    PubMed Central

    Xiang, Yang; Dong, Yi; Li, Xuan; Tang, Xin

    2016-01-01

    Purpose. To clarify the association of endothelial nitric oxide synthase (eNOS) polymorphisms and primary open angle glaucoma (POAG). Methods. After a systematic literature search in the MEDLINE, EMBASE, and ISI Web of Science databases, all relevant studies evaluating the association between the polymorphisms (rs2070744 and rs1799983) of eNOS gene and POAG were screened and included. The pooled odds ratios (ORs) and the 95% confidence interval (CI) of each single-nucleotide polymorphism (SNP) in five genetic models were estimated using fixed-effect model if I2 < 50% in the test for heterogeneity; otherwise the random-effects model was used. Results. Thirty-one records were obtained, with five being suitable for meta-analysis. The overall results showed that both TT genotype in rs2070744 and GG genotype in rs1799983 are associated with decreased risk of POAG susceptibility. Stratified analysis based on ethnicity showed that the association of rs2070744 with POAG remained only in Caucasians. Results of subgroup analysis by sex indicated association between both polymorphisms and POAG in female group, but not in male group. Conclusions. TT genotype and/or T-allele in rs2070744, as well as GG genotype and/or G-allele in rs1799983, was associated with decreased risk for POAG overall and in female group. PMID:27242919

  8. Finite-volume application of high order ENO schemes to multi-dimensional boundary-value problems

    NASA Technical Reports Server (NTRS)

    Casper, Jay; Dorrepaal, J. Mark

    1990-01-01

    The finite volume approach in developing multi-dimensional, high-order accurate essentially non-oscillatory (ENO) schemes is considered. In particular, a two dimensional extension is proposed for the Euler equation of gas dynamics. This requires a spatial reconstruction operator that attains formal high order of accuracy in two dimensions by taking account of cross gradients. Given a set of cell averages in two spatial variables, polynomial interpolation of a two dimensional primitive function is employed in order to extract high-order pointwise values on cell interfaces. These points are appropriately chosen so that correspondingly high-order flux integrals are obtained through each interface by quadrature, at each point having calculated a flux contribution in an upwind fashion. The solution-in-the-small of Riemann's initial value problem (IVP) that is required for this pointwise flux computation is achieved using Roe's approximate Riemann solver. Issues to be considered in this two dimensional extension include the implementation of boundary conditions and application to general curvilinear coordinates. Results of numerical experiments are presented for qualitative and quantitative examination. These results contain the first successful application of ENO schemes to boundary value problems with solid walls.

  9. Persistent neonatal hyperinsulinism.

    PubMed

    Mathew, P M; Young, J M; Abu-Osba, Y K; Mulhern, B D; Hammoudi, S; Hamdan, J A; Sa'di, A R

    1988-03-01

    Over a 3-year period, the diagnosis of persistent neonatal hyperinsulinism (PNH) was made in seven infants, from an unselected cohort of 18,726 births, all of Saudi Arabian origin. Thus the incidence of PNH was one in 2,675 births. The high incidence, associated consanguinity, and occurrence in siblings suggest that PNH may be inherited as an autosomal recessive disorder.

  10. The Persistence of PCBs.

    ERIC Educational Resources Information Center

    Boyle, Robert H.; Highland, Joseph H.

    1979-01-01

    PCB's are one of the most persistent chemicals ever introduced into the environment by man. From very early in their history of manufacture PCB's were suspected of being hazardous to health, but public awareness of the hazard was slow in coming. (RE)

  11. A Very Persistent Mistake

    ERIC Educational Resources Information Center

    McClelland, J. A. G.

    2011-01-01

    Articulated bodies with an internal energy source require to be coupled to an external mass in order to accelerate themselves but the typical text book assertion that the net force is provided by the external mass is not correct. Arguments are presented demonstrating that the assertion is incorrect and reasons are suggested for the persistence of…

  12. The Streptococcus pyogenes serotype M49 Nra-Ralp3 transcriptional regulatory network and its control of virulence factor expression from the novel eno ralp3 epf sagA pathogenicity region.

    PubMed

    Kreikemeyer, Bernd; Nakata, Masanobu; Köller, Thomas; Hildisch, Hendrikje; Kourakos, Vassilios; Standar, Kerstin; Kawabata, Shigetada; Glocker, Michael O; Podbielski, Andreas

    2007-12-01

    Many Streptococcus pyogenes (group A streptococcus [GAS]) virulence factor- and transcriptional regulator-encoding genes cluster together in discrete genomic regions. Nra is a central regulator of the FCT region. Previous studies exclusively described Nra as a transcriptional repressor of adhesin and toxin genes. Here transcriptome and proteome analysis of a serotype M49 GAS strain and an isogenic Nra mutant of this strain revealed the complete Nra regulon profile. Nra is active in all growth phases tested, with the largest regulon in the transition phase. Almost exclusively, virulence factor-encoding genes are repressed by Nra; these genes include the GAS pilus operon, the capsule synthesis operon, the cytolysin-mediated translocation system genes, all Mga region core virulence genes, and genes encoding other regulators, like the Ihk/Irr system, Rgg, and two additional RofA-like protein family regulators. Surprisingly, our experiments revealed that Nra additionally acts as a positive regulator, mostly for genes encoding proteins and enzymes with metabolic functions. Epidemiological investigations revealed strong genetic linkage of one particular Nra-repressed regulator, Ralp3 (SPy0735), with a gene encoding Epf (extracellular protein factor from Streptococcus suis). In a serotype-specific fashion, this ralp3 epf gene block is integrated, most likely via transposition, into the eno sagA virulence gene block, which is present in all GAS serotypes. In GAS serotypes M1, M4, M12, M28, and M49 this novel discrete genetic region is therefore designated the eno ralp3 epf sagA (ERES) pathogenicity region. Functional experiments showed that Epf is a novel GAS plasminogen-binding protein and revealed that Ralp3 activity counteracts Nra and MsmR regulatory activity. In addition to the Mga and FCT regions, the ERES region is the third discrete chromosomal pathogenicity region. All of these regions are transcriptionally linked, adding another level of complexity to the known

  13. Protein kinase D activity controls endothelial nitric oxide synthesis.

    PubMed

    Aicart-Ramos, Clara; Sánchez-Ruiloba, Lucía; Gómez-Parrizas, Mónica; Zaragoza, Carlos; Iglesias, Teresa; Rodríguez-Crespo, Ignacio

    2014-08-01

    Vascular endothelial growth factor (VEGF) regulates key functions of the endothelium, such as angiogenesis or vessel repair in processes involving endothelial nitric oxide synthase (eNOS) activation. One of the effector kinases that become activated in endothelial cells upon VEGF treatment is protein kinase D (PKD). Here, we show that PKD phosphorylates eNOS, leading to its activation and a concomitant increase in NO synthesis. Using mass spectrometry, we show that the purified active kinase specifically phosphorylates recombinant eNOS on Ser1179. Treatment of endothelial cells with VEGF or phorbol 12,13-dibutyrate (PDBu) activates PKD and increases eNOS Ser1179 phosphorylation. In addition, pharmacological inhibition of PKD and gene silencing of both PKD1 and PKD2 abrogate VEGF signaling, resulting in a clear diminished migration of endothelial cells in a wound healing assay. Finally, inhibition of PKD in mice results in an almost complete disappearance of the VEGF-induced vasodilatation, as monitored through determination of the diameter of the carotid artery. Hence, our data indicate that PKD is a new regulatory kinase of eNOS in endothelial cells whose activity orchestrates mammalian vascular tone. PMID:24928905

  14. Persistence, resistance, resonance

    NASA Astrophysics Data System (ADS)

    Tsadka, Maayan

    Sound cannot travel in a vacuum, physically or socially. The ways in which sound operates are a result of acoustic properties, and the ways by which it is considered to be music are a result of social constructions. Therefore, music is always political, regardless of its content: the way it is performed and composed; the choice of instrumentation, notation, tuning; the medium of its distribution; its inherent hierarchy and power dynamics, and more. My compositional praxis makes me less interested in defining a relationship between music and politics than I am in erasing---or at least blurring---the borders between them. In this paper I discuss the aesthetics of resonance and echo in their metaphorical, physical, social, and musical manifestations. Also discussed is a political aesthetic of resonance, manifested through protest chants. I transcribe and analyze common protest chants from around the world, categorizing and unifying them as universal crowd-mobilizing rhythms. These ideas are explored musically in three pieces. Sumud: Rhetoric of Resistance in Three Movements, for two pianos and two percussion players, is a musical interpretation of the political/social concept of sumud, an Arabic word that literally means "steadfastness" and represents Palestinian non-violent resistance. The piece is based on common protest rhythms and uses the acoustic properties inherent to the instruments. The second piece, Three Piano Studies, extends some of the musical ideas and techniques used in Sumud, and explores the acoustic properties and resonance of the piano. The final set of pieces is part of my Critical Mess Music Project. These are site-specific musical works that attempt to blur the boundaries between audience, performers and composer, in part by including people without traditional musical training in the process of music making. These pieces use the natural structure and resonance of an environment, in this case, locations on the UCSC campus, and offer an active

  15. Puerarin activates endothelial nitric oxide synthase through estrogen receptor-dependent PI3-kinase and calcium-dependent AMP-activated protein kinase

    SciTech Connect

    Hwang, Yong Pil; Kim, Hyung Gyun; Hien, Tran Thi; Jeong, Myung Ho; Jeong, Tae Cheon; Jeong, Hye Gwang

    2011-11-15

    The cardioprotective properties of puerarin, a natural product, have been attributed to the endothelial nitric oxide synthase (eNOS)-mediated production of nitric oxide (NO) in EA.hy926 endothelial cells. However, the mechanism by which puerarin activates eNOS remains unclear. In this study, we sought to identify the intracellular pathways underlying eNOS activation by puerarin. Puerarin induced the activating phosphorylation of eNOS on Ser1177 and the production of NO in EA.hy926 cells. Puerarin-induced eNOS phosphorylation required estrogen receptor (ER)-mediated phosphatidylinositol 3-kinase (PI3K)/Akt signaling and was reversed by AMP-activated protein kinase (AMPK) and calcium/calmodulin-dependent kinase II (CaMKII) inhibition. Importantly, puerarin inhibited the adhesion of tumor necrosis factor (TNF)-{alpha}-stimulated monocytes to endothelial cells and suppressed the TNF-{alpha} induced expression of intercellular cell adhesion molecule-1. Puerarin also inhibited the TNF-{alpha}-induced nuclear factor-{kappa}B activation, which was attenuated by pretreatment with N{sup G}-nitro-L-arginine methyl ester, a NOS inhibitor. These results indicate that puerarin stimulates eNOS phosphorylation and NO production via activation of an estrogen receptor-mediated PI3K/Akt- and CaMKII/AMPK-dependent pathway. Puerarin may be useful for the treatment or prevention of endothelial dysfunction associated with diabetes and cardiovascular disease. -- Highlights: Black-Right-Pointing-Pointer Puerarin induced the phosphorylation of eNOS and the production of NO. Black-Right-Pointing-Pointer Puerarin activated eNOS through ER-dependent PI3-kinase and Ca{sup 2+}-dependent AMPK. Black-Right-Pointing-Pointer Puerarin-induced NO was involved in the inhibition of NF-kB activation. Black-Right-Pointing-Pointer Puerarin may help for prevention of vascular dysfunction and diabetes.

  16. The Immunomodulator VacA Promotes Immune Tolerance and Persistent Helicobacter pylori Infection through Its Activities on T-Cells and Antigen-Presenting Cells

    PubMed Central

    Djekic, Aleksandra; Müller, Anne

    2016-01-01

    VacA is a pore-forming toxin that has long been known to induce vacuolization in gastric epithelial cells and to be linked to gastric disorders caused by H. pylori infection. Its role as a major colonization and persistence determinant of H. pylori is less well-understood. The purpose of this review is to discuss the various target cell types of VacA and its mechanism of action; specifically, we focus on the evidence showing that VacA targets myeloid cells and T-cells to directly and indirectly prevent H. pylori-specific T-cell responses and immune control of the infection. In particular, the ability of VacA-proficient H. pylori to skew T-cell responses towards regulatory T-cells and the effects of Tregs on H. pylori chronicity are highlighted. The by-stander effects of VacA-driven immunomodulation on extragastric diseases are discussed as well. PMID:27322319

  17. Pharmacodynamics of caspofungin in a murine model of systemic candidiasis: importance of persistence of caspofungin in tissues to understanding drug activity.

    PubMed

    Louie, Arnold; Deziel, Mark; Liu, Weiguo; Drusano, Michael F; Gumbo, Tawanda; Drusano, George L

    2005-12-01

    Pharmacokinetic and pharmacodynamic studies were conducted in a murine model of systemic candidiasis to determine the pharmacodynamic parameter linked with caspofungin efficacy. Additional studies defined the importance of persistent tissue drug concentrations to treatment outcome. The pharmacokinetics of caspofungin were determined in the serum and kidneys of infected mice over 96 h. Population pharmacokinetic analysis demonstrated a serum terminal half-life (t(1/2)) for caspofungin of 20.2 h when only serum concentrations were considered, but the terminal t(1/2) increased to 59.2 h when serum and kidney concentration-time data were co-modeled. In dose-range studies, the dose-response effect was well described by an inhibitory sigmoid curve for the exposure-effect killing caused by the drug (r2 > 0.96; P < 0.001). In dose-fractionation studies, fungal counts in kidneys were not statistically different for total doses given as one, two, or four equally divided doses over 96 h, indicating that the area under the concentration-time curve/MIC is the pharmacodynamic parameter that predicts caspofungin efficacy in our infection model. In a separate study, mice infected with Candida albicans 24 h after serum concentrations of caspofungin fell below the MIC for the fungal isolate had significant reductions in fungal densities in their kidneys compared with the growth of fungi in the kidneys of untreated controls (P = 0.005). This in vivo biological assay demonstrates that therapeutic concentrations of caspofungin persist at the site of infection in kidney tissue well after serum concentrations fall below the MIC, underscoring the primacy of caspofungin levels in tissues on determining treatment outcome.

  18. Radiation persistently promoted oxidative stress, activated mTOR via PI3K/Akt, and downregulated autophagy pathway in mouse intestine.

    PubMed

    Datta, Kamal; Suman, Shubhankar; Fornace, Albert J

    2014-12-01

    While acute effects of toxic radiation doses on intestine are well established, we are yet to acquire a complete spectrum of sub-lethal radiation-induced chronic intestinal perturbations at the molecular level. We investigated persistent effects of a radiation dose (2 Gy) commonly used as a daily fraction in radiotherapy on oxidants and anti-oxidants, and autophagy pathways, which are interlinked processes affecting intestinal homeostasis. Six to eight weeks old C57BL/6J mice (n=10) were exposed to 2 Gy γ-ray. Mice were euthanized two or twelve months after radiation, intestine surgically removed, and flushed using sterile PBS. Parts of the intestine from jejunal-ilial region were fixed, frozen, or used for intestinal epithelial cell (IEC) isolation. While oxidant levels and mitochondrial status were assessed in isolated IEC, autophagy and oxidative stress related signaling pathways were probed in frozen and fixed samples using PCR-based expression arrays and immunoprobing. Radiation exposure caused significant alterations in the expression level of 26 autophagy and 17 oxidative stress related genes. Immunoblot results showed decreased Beclin1 and LC3-II and increased p62, PI3K/Akt, and mTOR. Flow cytometry data showed increased oxidant production and compromised mitochondrial integrity in irradiated samples. Immunoprobing of intestinal sections showed increased 8-oxo-dG and nuclear PCNA, and decreased autophagosome marker LC3-II in IEC after irradiation. We show that sub-lethal radiation could persistently downregulate anti-oxidants and autophagy signaling, and upregulate oxidant production and proliferative signaling. Radiation-induced promotion of oxidative stress and downregulation of autophagy could work in tandem to alter intestinal functions and have implications for post-radiation chronic gastrointestinal diseases.

  19. Pharmacodynamics of Caspofungin in a Murine Model of Systemic Candidiasis: Importance of Persistence of Caspofungin in Tissues to Understanding Drug Activity

    PubMed Central

    Louie, Arnold; Deziel, Mark; Liu, Weiguo; Drusano, Michael F.; Gumbo, Tawanda; Drusano, George L.

    2005-01-01

    Pharmacokinetic and pharmacodynamic studies were conducted in a murine model of systemic candidiasis to determine the pharmacodynamic parameter linked with caspofungin efficacy. Additional studies defined the importance of persistent tissue drug concentrations to treatment outcome. The pharmacokinetics of caspofungin were determined in the serum and kidneys of infected mice over 96 h. Population pharmacokinetic analysis demonstrated a serum terminal half-life (t1/2) for caspofungin of 20.2 h when only serum concentrations were considered, but the terminal t1/2 increased to 59.2 h when serum and kidney concentration-time data were comodeled. In dose-range studies, the dose-response effect was well described by an inhibitory sigmoid curve for the exposure-effect killing caused by the drug (r2 > 0.96; P ≪ 0.001). In dose-fractionation studies, fungal counts in kidneys were not statistically different for total doses given as one, two, or four equally divided doses over 96 h, indicating that the area under the concentration-time curve/MIC is the pharmacodynamic parameter that predicts caspofungin efficacy in our infection model. In a separate study, mice infected with Candida albicans 24 h after serum concentrations of caspofungin fell below the MIC for the fungal isolate had significant reductions in fungal densities in their kidneys compared with the growth of fungi in the kidneys of untreated controls (P = 0.005). This in vivo biological assay demonstrates that therapeutic concentrations of caspofungin persist at the site of infection in kidney tissue well after serum concentrations fall below the MIC, underscoring the primacy of caspofungin levels in tissues on determining treatment outcome. PMID:16304173

  20. Role of blood pressure and the renin-angiotensin system in development of diabetic nephropathy (DN) in eNOS-/- db/db mice.

    PubMed

    Zhang, Ming-Zhi; Wang, Suwan; Yang, Shilin; Yang, Haichun; Fan, Xiaofeng; Takahashi, Takamune; Harris, Raymond C

    2012-02-15

    Randomized clinical trials have clearly shown that inhibition of the renin-angiotensin system (RAS) will slow the rate of progression of diabetic nephropathy, but controversy remains about whether the observed beneficial effects result from more than control of blood pressure. Deletion of eNOS in a model of type II diabetes, db/db mice (eNOS(-/-) db/db), induces an accelerated nephropathy and provides an excellent model of human diabetic nephropathy. As is frequently seen in type II diabetes, blood pressure is moderately elevated in eNOS(-/-) db/db mice. To determine the role of elevated blood pressure per se vs. additional deleterious effects of the RAS in mediation of disease progression, 8-wk-old eNOS(-/-) db/db mice were randomly divided into three groups: vehicle, treatment with the angiotensin-converting enzyme inhibitor (ACEI) captopril, or treatment with "triple therapy" (hydralazine, resperine, hydrocholorothiazide), and the animals were euthanized after treatment for 12 wk. Blood pressure was reduced to comparable levels with ACE inhibition or triple therapy. Although both treatment regimens decreased development of diabetic nephropathy, ACE inhibition led to more profound reductions in albuminuria, glomerulosclerosis, markers of tubulointerstitial injury, macrophage infiltration, and markers of inflammation. Therefore, this animal model suggests that while there is an important role for blood pressure control, RAS blockade provides additional benefits in slowing the progression of diabetic nephropathy. PMID:22114203

  1. [T(-786) --> C-polymorphism of the endothelial nitric oxide synthase promoter gene (eNOS) and exercise performance in sport].

    PubMed

    Drozdovs'ka, S B; Lysenko, O M; Dosenko, V Ie; Il'ïn, V M; Moĭbenko, O O

    2013-01-01

    Given the significant impact of the T(-786) --> C-polymorphism of the eNOS gene in the process of adaptation to physical stress, we aimed to investigate the effect of this polymorphism on physical performance in sportsmen and establish the possibility of its use as a marker of predisposition to the sport. DNA of 516 people, of which 195 qualified athletes and 321 people who had no experience of regular exercise was investigated. The frequency of genotypes and alleles of the T(-786) --> C-polymorphism of the eNOS gene in groups of athletes of different sports, the distribution of genotypes and alleles among athletes and those who are not involved in sports were studied. T allele frequency in a group of athletes on 6.4% (r(chi)2 = 0.03) than in control group. The association of the T allele of the T(-786) --> C-polymorphism of the eNOS gene with a predisposition for speed and power was established. In the group of athletes in speed and power sports, the T-allele frequency was higher than that in the control group by 12% (r(chi)2 = 0.002) and than in group endurance sports by 10% (r(chi)2 = 0.004). We found that the T(-786) --> C-polymorphism of the eNOS gene influence the power and efficiency ofthe functioning of the cardiorespiratory system of athletes during exercise.

  2. Persistent pesticides in Mexico.

    PubMed

    Albert, L A

    1996-01-01

    As part of the recent increase in the international interest in persistent organic pollutants and their environmental and health hazards, it was found that although most of them have been severely controlled in developed countries, in most developing countries--including Mexico--their import, use, and in some cases production have continued up to the present without sufficient or adequate controls. Despite the large and continuing use of persistent organic chemicals in Mexico in agriculture, public health, and industry, data on their import, production, use, disposal, and the presence of their residues in the environment, food, and human tissues are extremely scarce and widely dispersed. This review is devoted only to the use of persistent pesticides in Mexico; it is the first effort to locate, gather, and analyze this information and to summarize and discuss the past and current situation of the control of these chemicals in Mexico. This review discusses the general background for the use of these pesticides in the country, including historical development, the reasons for substitution by less persistent products in crops intended for export, and the undesirable effect of this substitution on the health of migratory agricultural workers. The current status of the legal framework for the control of pesticides in Mexico is presented with emphasis on its slow and haphazard development; the legal, technical, and administrative reasons for the insufficient enforcement and oversight of the existing regulations and standards are highlighted. The low priority of this research area for the Mexican science and technology authorities and the negative consequences of this low priority on the existence of sufficient reliable data on pesticide residues in the environment and humans in Mexico are also discussed. The available data on production and uses of persistent pesticides in Mexico are presented, and the existing information on their residues in the environment, biota

  3. Role of T-helper type 2 cytokines in down-modulation of fas mRNA and receptor on the surface of activated CD4(+) T cells: molecular basis for the persistence of the allergic immune response.

    PubMed

    Spinozzi, F; Agea, E; Fizzotti, M; Bassotti, G; Russano, A; Droetto, S; Bistoni, O; Grignani, F; Bertotto, A

    1998-12-01

    The mechanisms responsible for persistence of T lymphocytes at the sites of allergic inflammation are not completely understood. Activated T cells, usually expressing Fas on their surface, undergo activation-induced apoptotic death, thus limiting the dangerous consequences of a persistent immune reaction. We have previously shown that pulmonary T lymphocytes from untreated asthmatic subjects do not express surface Fas receptors nor do they contain Fas mRNA, yet they display normal levels of Fas ligand. This is not an inherited defect and is confined to mucosal T cells. To gain insights into the mechanism responsible for these findings, we performed a set of experiments with both purified Dermatophagoides pteronyssinus allergen and recombinant human cytokines: interleukin 2 (IL-2), IL-4, IL-5, transforming growth factor beta1, interferon gamma, and granulocyte-macrophage colony-stimulating factor (GM-CSF). In vitro exposure of purified CD4(+) lymphocytes to allergen yielded only transient up-regulation of surface Fas but did not influence susceptibility to Fas-mediated cell death. T-helper type 2 cytokines (IL-4, IL-5, and GM-CSF) had a dose-dependent and specific inhibitory effect on Fas mRNA, suggesting a new fundamental biological role in the survival of inflammatory cells during allergen exposure. PMID:9837865

  4. Chronic aerobic exercise associated to dietary modification improve endothelial function and eNOS expression in high fat fed hamsters.

    PubMed

    Boa, Beatriz C S; Souza, Maria das Graças C; Leite, Richard D; da Silva, Simone V; Barja-Fidalgo, Thereza Christina; Kraemer-Aguiar, Luiz Guilherme; Bouskela, Eliete

    2014-01-01

    Obesity is epidemic in the western world and central adipose tissue deposition points to increased cardiovascular morbidity and mortality, independently of any association between obesity and other cardiovascular risk factors. Physical exercise has been used as non-pharmacological treatment to significantly reverse/attenuate obesity comorbidities. In this study we have investigated effects of exercise and/or dietary modification on microcirculatory function, body composition, serum glucose, iNOS and eNOS expression on 120 male hamsters treated for 12 weeks with high fat chow (HF, n = 30) starting on the 21st day of birth. From week 12 to 20, animals were randomly separated in HF (no treatment change), return to standard chow (HFSC, n = 30), high fat chow associated to an aerobic exercise training program (AET) (HFEX, n = 30) and return to standard chow+AET (HFSCEX, n = 30). Microvascular reactivity in response to acetylcholine and sodium nitroprusside and macromolecular permeability increase induced by 30 minutes ischemia followed by reperfusion were assessed on the cheek pouch preparation. Total body fat and aorta eNOS and iNOS expression by immunoblotting assay were evaluated on the experimental day. Compared to HFSC and HFSCEX groups, HF and HFEX ones presented increased visceral fat [(mean±SEM) (HF)4.9±1.5 g and (HFEX)4.7±0.9 g vs. (HFSC)*3.0±0.7 g and (HFSCEX)*1.9±0.4 g/100 g BW]; impaired endothelial-dependent vasodilatation [Ach 10(-8) M (HF)87.9±2.7%; (HFSC)*116.7±5.9%; (HFEX)*109.1±4.6%; (HFSCEX)*105±2.8%; Ach10(-6) M (HF)95.3±3.1%; (HFSC)*126±6.2%; (HFEX)*122.5±2.8%; (HFSCEX)*118.1±4.3% and Ach10(-4) M (HF)109.5±4.8%; (HFSC)*149.6±6.6%; (HFEX)*143.5±5.4% and (HFSCEX)*139.4±5.2%], macromolecular permeability increase after ischemia/reperfusion [(HF)40.5±4.2; (HFSC)*19.0±1.6; (HFEX)*18.6±2.1 and (HFSCEX)* 21.5±3.7 leaks/cm2), decreased eNOS expression, increased leptin and glycaemic levels. Endothelial

  5. Finite-volume application of high-order ENO schemes to two-dimensional boundary-value problems

    NASA Technical Reports Server (NTRS)

    Casper, Jay

    1991-01-01

    Finite-volume applications of high-order accurate ENO schemes to two-dimensional boundary-value problems are studied. These schemes achieve high-order spatial accuracy, in smooth regions, by a piecewise polynomial approximation of the solution from cell averages. In addition, this spatial operation involves an adaptive stencil algorithm in order to avoid the oscillatory behavior that is associated with interpolation across steep gradients. High-order TVD Runge-Kutta methods are employed for time integration, thus making these schemes best suited for unsteady problems. Fifth- and sixth-order accurate applications are validated through a grid refinement study involving the solutions of scalar hyperbolic equations. A previously proposed extension for the Euler equations of gas dynamics is tested, including its application to solutions of boundary-value problems involving solid walls and curvilinear coordinates.

  6. A Multilevel Prediction of Physiological Response to Challenge: Interactions among Child Maltreatment, Neighborhood Crime, eNOS and GABRA6

    PubMed Central

    Lynch, Michael; Manly, Jody Todd; Cicchetti, Dante

    2015-01-01

    Physiological response to stress has been linked to variety of healthy and pathological conditions. The current study conducted a multilevel examination of interactions among environmental toxins – i.e., neighborhood crime and child maltreatment – and specific genetic polymorphisms of eNOS and GABRA6. A total of 186 children were recruited at age 4. At this time, the presence or absence of child maltreatment was determined, as was the amount of crime that occurred in their neighborhood during the previous year. At age 9, the children were brought to the lab where their physiological response to a cognitive challenge – i.e., change in the amplitude of RSA – was assessed and DNA samples were collected for subsequent genotyping. Results confirmed that complex G x G, E x E, and G x E interactions were associated with different patterns of RSA reactivity. The implications for future research and evidence-based intervention are discussed. PMID:26535938

  7. T helper cell-mediated interferon-gamma expression after human parvovirus B19 infection: persisting VP2-specific and transient VP1u-specific activity.

    PubMed

    Franssila, R; Auramo, J; Modrow, S; Möbs, M; Oker-Blom, C; Käpylä, P; Söderlund-Venermo, M; Hedman, K

    2005-10-01

    Human parvovirus B19 is a small non-enveloped DNA virus with an icosahedral capsid consisting of proteins of only two species, the major protein VP2 and the minor protein VP1. VP2 is contained within VP1, which has an additional unique portion (VP1u) of 227 amino acids. We determined the ability of eukaryotically expressed parvovirus B19 virus-like particles consisting of VP1 and VP2 in the ratio recommended for vaccine use, or of VP2 alone, to stimulate, in an HLA class II restricted manner, peripheral blood mononuclear cells (PBMC) to proliferate and to secrete interferon gamma (IFN-gamma) and interleukin (IL)-10 cytokines among recently and remotely B19 infected subjects. PBMC reactivity with VP1u was determined specifically with a prokaryotically expressed VP1u antigen. In general, B19-specific IFN-gamma responses were stronger than IL-10 responses in both recent and remote infection; however, IL-10 responses were readily detectable among both groups, with the exception of patients with relapsed or persisting symptoms who showed strikingly low IL-10 responses. Whereas VP1u-specific IFN-gamma responses were very strong among the recently infected subjects, the VP1u-specific IFN-gamma and IL-10 responses were virtually absent among the remotely infected subjects. The disappearance of VP1u-specific IFN-gamma expression is surprising, as B-cell immunity against VP1u is well maintained.

  8. T helper cell-mediated interferon-gamma expression after human parvovirus B19 infection: persisting VP2-specific and transient VP1u-specific activity

    PubMed Central

    Franssila, R; Auramo, J; Modrow, S; Möbs, M; Oker-Blom, C; Käpylä, P; Söderlund-Venermo, M; Hedman, K

    2005-01-01

    Human parvovirus B19 is a small non-enveloped DNA virus with an icosahedral capsid consisting of proteins of only two species, the major protein VP2 and the minor protein VP1. VP2 is contained within VP1, which has an additional unique portion (VP1u) of 227 amino acids. We determined the ability of eukaryotically expressed parvovirus B19 virus-like particles consisting of VP1 and VP2 in the ratio recommended for vaccine use, or of VP2 alone, to stimulate, in an HLA class II restricted manner, peripheral blood mononuclear cells (PBMC) to proliferate and to secrete interferon gamma (IFN-γ) and interleukin (IL)-10 cytokines among recently and remotely B19 infected subjects. PBMC reactivity with VP1u was determined specifically with a prokaryotically expressed VP1u antigen. In general, B19-specific IFN-γ responses were stronger than IL-10 responses in both recent and remote infection; however, IL-10 responses were readily detectable among both groups, with the exception of patients with relapsed or persisting symptoms who showed strikingly low IL-10 responses. Whereas VP1u-specific IFN-γ responses were very strong among the recently infected subjects, the VP1u-specific IFN-γ and IL-10 responses were virtually absent among the remotely infected subjects. The disappearance of VP1u-specific IFN-γ expression is surprising, as B-cell immunity against VP1u is well maintained. PMID:16178856

  9. Alteration in cardiac uncoupling proteins and eNOS gene expression following high-intensity interval training in favor of increasing mechanical efficiency

    PubMed Central

    Fallahi, Ali Asghar; Shekarfroush, Shahnaz; Rahimi, Mostafa; Jalali, Amirhossain; Khoshbaten, Ali

    2016-01-01

    Objective(s): High-intensity interval training (HIIT) increases energy expenditure and mechanical energy efficiency. Although both uncoupling proteins (UCPs) and endothelial nitric oxide synthase (eNOS) affect the mechanical efficiency and antioxidant capacity, their effects are inverse. The aim of this study was to determine whether the alterations of cardiac UCP2, UCP3, and eNOS mRNA expression following HIIT are in favor of increased mechanical efficiency or decreased oxidative stress. Materials and Methods: Wistar rats were divided into five groups: control group (n=12), HIIT for an acute bout (AT1), short term HIIT for 3 and 5 sessions (ST3 and ST5), long-term training for 8 weeks (LT) (6 in each group). The rats of the training groups were made to run on a treadmill for 60 min in three stages: 6 min running for warm-up, 7 intervals of 7 min running on treadmill with a slope of 5° to 20° (4 min with an intensity of 80-110% VO2max and 3 min at 50-60% VO2max), and 5-min running for cool-down. The control group did not participate in any exercise program. Rats were sacrificed and the hearts were extracted to analyze the levels of UCP2, UCP3 and eNOS mRNA by RT-PCR. Results: UCP3 expression was increased significantly following an acute training bout. Repeated HIIT for 8 weeks resulted in a significant decrease in UCPs mRNA and a significant increase in eNOS expression in cardiac muscle. Conclusion: This study indicates that Long term HIIT through decreasing UCPs mRNA and increasing eNOS mRNA expression may enhance energy efficiency and physical performance. PMID:27114795

  10. eNOS gene deletion restores blood-brain barrier integrity and attenuates neurodegeneration in the thiamine-deficient mouse brain.

    PubMed

    Beauchesne, Elizabeth; Desjardins, Paul; Hazell, Alan S; Butterworth, Roger F

    2009-10-01

    Wernicke's encephalopathy is a cerebral disorder caused by thiamine (vitamin B(1)) deficiency (TD). Neuropathologic consequences of TD include region-selective neuronal cell loss and blood-brain barrier (BBB) breakdown. Early increased expression of the endothelial isoform of nitric oxide synthase (eNOS) occurs selectively in vulnerable brain regions in TD. We hypothesize that region-selective eNOS induction in TD leads to altered expression of tight junction proteins and BBB breakdown. In order to address this issue, TD was induced in C57BL/6 wild-type (WT) and eNOS(-/-) mice by feeding a thiamine-deficient diet and treatment with the thiamine antagonist pyrithiamine. Pair-fed control mice were fed the same diet with additional thiamine. In medial thalamus of TD-WT mice (vulnerable area), increased heme oxygenase-1 and S-nitrosocysteine immunostaining was observed in vessel walls, compared to pair-fed control-WT mice. Concomitant increases in IgG extravasation, decreases in expression of the tight junction proteins occludin, zona occludens-1 and zona occludens-2, and up-regulation of matrix metalloproteinase-9 in endothelial cells were observed in the medial thalamus of TD-WT mice. eNOS gene deletion restored these BBB alterations, suggesting that eNOS-derived nitric oxide is a major factor leading to cerebrovascular alterations in TD. However, eNOS gene deletion only partially attenuated TD-related neuronal cell loss, suggesting the presence of mechanisms additional to BBB disruption in the pathogenesis of these changes.

  11. Learning's "Weak" Link to Persistence

    ERIC Educational Resources Information Center

    Wolniak, Gregory C.; Mayhew, Matthew J.; Engberg, Mark E.

    2012-01-01

    This study advances the understanding of college persistence by examining five dimensions of student learning in relation to second-year persistence. Two of the five dimensions of learning were found to be significant predictors of persistence, and each was moderated by social integration. (Contains 5 tables and 1 figure.)

  12. The -665 C>T polymorphism in the eNOS gene predicts cardiovascular mortality and morbidity in white Europeans.

    PubMed

    Olivi, L; Gu, Y M; Salvi, E; Liu, Y P; Thijs, L; Velayutham, D; Jin, Y; Jacobs, L; D'Avila, F; Petit, T; Barcella, M; Lanzani, C; Kuznetsova, T; Manunta, P; Barlassina, C; Cusi, D; Staessen, J A

    2015-03-01

    We recently identified rs3918226 as a hypertension susceptibility locus (-665 C>T), TT homozygosity being associated with higher hypertension risk. T compared with C allele transfected cells had lower endothelial nitric oxide synthase (eNOS) expression. In the family-based Flemish Study on Environment, Genes and Health Outcomes (50.9% women; mean age 40.3 years), we investigated whether 32 TT homozygotes had worse outcomes than 2787 C allele carriers. Over 15 years (median), total and cardiovascular mortality and cardiovascular and coronary events amounted to 269 (9.5%), 98 (3.5%), 247 (8.8%) and 120 (4.3%), respectively. While accounting for family clusters, the hazard ratios associated with TT homozygosity were 4.11 (P=0.0052) for cardiovascular mortality (4 deaths), 2.75 (P=0.0067) for cardiovascular events (7 endpoints) and 3.10 (P=0.022) for coronary events (4 endpoints). With adjustment for cardiovascular risk factors, these hazard ratios were 6.01 (P=0.0003), 2.64 (P=0.0091) and 2.89 (P=0.010), respectively. Analyses unadjusted for blood pressure and antihypertensive treatment produced consistent results. For all fatal plus nonfatal cardiovascular events, the positive predictive value, attributable risk and population-attributable risk associated with TT homozygosity were 21.9, 61.5 and 2.0%, respectively. In conclusion, TT homozygosity at the position -665 in the eNOS promoter predicts adverse outcomes, independent of blood pressure and other risk factors.

  13. The -665 C>T polymorphism in the eNOS gene predicts cardiovascular mortality and morbidity in white Europeans.

    PubMed

    Olivi, L; Gu, Y M; Salvi, E; Liu, Y P; Thijs, L; Velayutham, D; Jin, Y; Jacobs, L; D'Avila, F; Petit, T; Barcella, M; Lanzani, C; Kuznetsova, T; Manunta, P; Barlassina, C; Cusi, D; Staessen, J A

    2015-03-01

    We recently identified rs3918226 as a hypertension susceptibility locus (-665 C>T), TT homozygosity being associated with higher hypertension risk. T compared with C allele transfected cells had lower endothelial nitric oxide synthase (eNOS) expression. In the family-based Flemish Study on Environment, Genes and Health Outcomes (50.9% women; mean age 40.3 years), we investigated whether 32 TT homozygotes had worse outcomes than 2787 C allele carriers. Over 15 years (median), total and cardiovascular mortality and cardiovascular and coronary events amounted to 269 (9.5%), 98 (3.5%), 247 (8.8%) and 120 (4.3%), respectively. While accounting for family clusters, the hazard ratios associated with TT homozygosity were 4.11 (P=0.0052) for cardiovascular mortality (4 deaths), 2.75 (P=0.0067) for cardiovascular events (7 endpoints) and 3.10 (P=0.022) for coronary events (4 endpoints). With adjustment for cardiovascular risk factors, these hazard ratios were 6.01 (P=0.0003), 2.64 (P=0.0091) and 2.89 (P=0.010), respectively. Analyses unadjusted for blood pressure and antihypertensive treatment produced consistent results. For all fatal plus nonfatal cardiovascular events, the positive predictive value, attributable risk and population-attributable risk associated with TT homozygosity were 21.9, 61.5 and 2.0%, respectively. In conclusion, TT homozygosity at the position -665 in the eNOS promoter predicts adverse outcomes, independent of blood pressure and other risk factors. PMID:25102225

  14. AMP-activated protein kinase (AMPK) regulates the insulin-induced activation of the nitric oxide synthase in human platelets.

    PubMed

    Fleming, Ingrid; Schulz, Christian; Fichtlscherer, Birgit; Kemp, Bruce E; Fisslthaler, Beate; Busse, Rudi

    2003-11-01

    Little is known about the signaling cascades that eventually regulate the activity of the endothelial nitric oxide synthase (eNOS) in platelets. Here, we investigated the effects of insulin on the phosphorylation and activation of eNOS in washed human platelets and in endothelial cells. Insulin activated the protein kinase Akt in cultured endothelial cells and increased the phosphorylation of eNOS on Ser(1177) but failed to increase endothelial cyclic GMP levels or to elicit the relaxation of endothelium-intact porcine coronary arteries. In platelets, insulin also elicited the activation of Akt as well as the phosphorylation of eNOS and initiated NO production which was associated with increased cyclic GMP levels and the inhibition of thrombin-induced aggregation. The insulin-induced inhibition of aggregation was accompanied by a decreased Ca(2+) response to thrombin and was also prevented by N(omega) nitro-L-arginine. In platelets, but not in endothelial cells, insulin induced the activation of the AMP-activated protein kinase (AMPK), a metabolic stress-sensing kinase which was sensitive to the phosphatidylinositol 3-kinase (PI3-K) inhibitor wortmannin and the AMPK inhibitor iodotubercidin. Moreover, the insulin-mediated inhibition of thrombin-induced aggregation was prevented by iodotubercidin. Insulin-independent activation of the AMPK using 5-aminoimidazole-4-carboxamide ribonucleoside, increased platelet eNOS phosphorylation, increased cyclic GMP levels and attenuated platelet aggregation. These results highlight the differences in the signal transduction cascade activated by insulin in endothelial cells and platelets, and demonstrate that insulin stimulates the formation of NO in human platelets, in the absence of an increase in Ca(2+), by acti-vating PI3-K and AMPK which phosphorylates eNOS on Ser(1177).

  15. Persistence of Salmonid Redds

    NASA Astrophysics Data System (ADS)

    Buffington, J. M.; Buxton, T.; Fremier, A. K.; Hassan, M. A.; Yager, E.

    2013-12-01

    The construction of redds by spawning salmonids modifies fluvial processes in ways that are beneficial to egg and embryo survival. Redd topography induces hyporheic flow that oxygenates embryos incubating within the streambed and creates form drag that reduces bed mobility and scour of salmonid eggs. Winnowing of fine material during redd construction also coarsens the streambed, increasing bed porosity and hyporheic flow and reducing bed mobility. In addition to the biological benefits, redds may influence channel morphology by altering channel hydraulics and bed load transport rates depending on the size and extent of redds relative to the size of the channel. A key question is how long do the physical and biological effects of redds last? Field observations indicate that in some basins redds are ephemeral, with redd topography rapidly erased by subsequent floods, while in other basins, redds can persist for years. We hypothesize that redd persistence is a function of basin hydrology, sediment supply, and characteristics of the spawning fish. Hydrology controls the frequency and magnitude of bed mobilizing flows following spawning, while bed load supply (volume and caliber) controls the degree of textural fining and consequent bed mobility after spawning, as well as the potential for burial of redd features. The effectiveness of flows in terms of their magnitude and duration depend on hydroclimate (i.e., snowmelt, rainfall, or transitional hydrographs), while bed load supply depends on basin geology, land use, and natural disturbance regimes (e.g., wildfire). Location within the stream network may also influence redd persistence. In particular, lakes effectively trap sediment and regulate downstream flow, which may promote long-lived redds in stream reaches below lakes. These geomorphic controls are modulated by biological factors: fish species (size of fish controls size of redds and magnitude of streambed coarsening); life history (timing of spawning and

  16. Persistence of West Nile virus.

    PubMed

    Garcia, Melissa N; Hasbun, Rodrigo; Murray, Kristy O

    2015-02-01

    West Nile virus (WNV) is a widespread global pathogen that results in significant morbidity and mortality. Data from animal models provide evidence of persistent renal and neurological infection from WNV; however, the possibility of persistent infection in humans and long-term neurological and renal outcomes related to viral persistence remain largely unknown. In this paper, we provide a review of the literature related to persistent infection in parallel with the findings from cohorts of patients with a history of WNV infection. The next steps for enhancing our understanding of WNV as a persistent pathogen are discussed.

  17. Persistence of airline accidents.

    PubMed

    Barros, Carlos Pestana; Faria, Joao Ricardo; Gil-Alana, Luis Alberiko

    2010-10-01

    This paper expands on air travel accident research by examining the relationship between air travel accidents and airline traffic or volume in the period from 1927-2006. The theoretical model is based on a representative airline company that aims to maximise its profits, and it utilises a fractional integration approach in order to determine whether there is a persistent pattern over time with respect to air accidents and air traffic. Furthermore, the paper analyses how airline accidents are related to traffic using a fractional cointegration approach. It finds that airline accidents are persistent and that a (non-stationary) fractional cointegration relationship exists between total airline accidents and airline passengers, airline miles and airline revenues, with shocks that affect the long-run equilibrium disappearing in the very long term. Moreover, this relation is negative, which might be due to the fact that air travel is becoming safer and there is greater competition in the airline industry. Policy implications are derived for countering accident events, based on competition and regulation.

  18. Six persistent research misconceptions.

    PubMed

    Rothman, Kenneth J

    2014-07-01

    Scientific knowledge changes rapidly, but the concepts and methods of the conduct of research change more slowly. To stimulate discussion of outmoded thinking regarding the conduct of research, I list six misconceptions about research that persist long after their flaws have become apparent. The misconceptions are: 1) There is a hierarchy of study designs; randomized trials provide the greatest validity, followed by cohort studies, with case-control studies being least reliable. 2) An essential element for valid generalization is that the study subjects constitute a representative sample of a target population. 3) If a term that denotes the product of two factors in a regression model is not statistically significant, then there is no biologic interaction between those factors. 4) When categorizing a continuous variable, a reasonable scheme for choosing category cut-points is to use percentile-defined boundaries, such as quartiles or quintiles of the distribution. 5) One should always report P values or confidence intervals that have been adjusted for multiple comparisons. 6) Significance testing is useful and important for the interpretation of data. These misconceptions have been perpetuated in journals, classrooms and textbooks. They persist because they represent intellectual shortcuts that avoid more thoughtful approaches to research problems. I hope that calling attention to these misconceptions will spark the debates needed to shelve these outmoded ideas for good. PMID:24452418

  19. Persistent activation by constitutive Ste7 promotes Kss1-mediated invasive growth but fails to support Fus3-dependent mating in yeast.

    PubMed

    Maleri, Seth; Ge, Qingyuan; Hackett, Elizabeth A; Wang, Yuqi; Dohlman, Henrik G; Errede, Beverly

    2004-10-01

    Mitogen-activated protein kinase kinase kinase-Ste11 (MAPKKK-Ste11), MAPKK-Ste7, and MAPK-Kss1 mediate pheromone-induced mating differentiation and nutrient-responsive invasive growth in Saccharomyces cerevisiae. The mating pathway also requires the scaffold-Ste5 and the additional MAPK-Fus3. One contribution to specificity in this system is thought to come from stimulus-dependent recruitment of the MAPK cascade to upstream activators that are unique to one or the other pathway. To test this premise, we asked if stimulus-independent signaling by constitutive Ste7 would lead to a loss of biological specificity. Instead, we found that constitutive Ste7 promotes invasion without supporting mating responses. This specificity occurs because constitutive Ste7 activates Kss1, but not Fus3, in vivo and promotes filamentation gene expression while suppressing mating gene expression. Differences in the ability of constitutive Ste7 variants to bind the MAPKs and Ste5 account for the selective activation of Kss1. These findings support the model that Fus3 activation in vivo requires binding to both Ste7 and the scaffold-Ste5 but that Kss1 activation is independent of Ste5. This scaffold-independent activation of Kss1 by constitutive Ste7 and the existence of mechanisms for pathway-specific promoter discrimination impose a unique developmental fate independently of any distinguishing external stimuli. PMID:15456892

  20. Quantitative genetics of natural variation of behavior in Drosophila melanogaster: the possible role of the social environment on creating persistent patterns of group activity.

    PubMed

    Higgins, Laura A; Jones, Kelly M; Wayne, Marta L

    2005-07-01

    Using a set of nine effectively isogenic lines collected from nature in 1998, we observed unperturbed behaviors of mixed-sex groups of Drosophila melanogaster. We repeatedly scanned replicated groups of genetically identical individuals, five females and five males, and recorded the behavior of each individual (i.e., walking, feeding, grooming, flying, courting, mating, fighting, or resting). From these behaviors, we made a composite variable of activity for our quantitative genetic analysis. Genotypes differed in activity, explaining 14.41% of the variation in activity; 8.60% of the variation was explained by a significant genotype x sex interaction, which signifies genetic variation for sexual dimorphism in behavior. Phenotypic plasticity explained 11.13% of the variation in activity. Different genotypes and sexes within genotypes had different rank orders of the component behaviors that contribute to activity. We found no effect of common rearing environment. Instead, differences between replicate groups within genotype accounted for 19.47% variation in activity, and activity was significantly repeatable across scans. This emergent group behavior is likely caused by differences between groups of interacting individuals, even though individuals were genetically identical across groups. Thus, emergent group behavior explained almost as much variation in activity as the combined sources of genetic variation (23.01%), and this is an additional level on which selection could operate: individuals and groups. We discuss how differences among groups could change patterns of additive genetic variation available for evolution. Furthermore, because the behavior of an individual is influenced by conspecifics, genotype interactions between individuals could contribute to indirect selection. Finally, if we consider activity as a syndrome governing all component behaviors with strong genetic correlations among behaviors within an individual, then these component behaviors

  1. New daily persistent headache: an update.

    PubMed

    Rozen, Todd D

    2014-07-01

    New daily persistent headache is a primary headache disorder marked by a unique temporal profile which is daily from onset. For many sufferers this is their first ever headache. Very little is known about the pathogenesis of this condition. It might be a disorder of abnormal glial activation with persistent central nervous system inflammation and it may be a syndrome that occurs in individuals who have a history of cervical hypermobility. At present there is no known specific treatment and many patients go for years to decades without any improvement in their condition despite aggressive therapy. This article will present an up-to-date overview of new daily persistent headache on the topics of clinical presentation, treatment, diagnostic criteria, and presumed pathogenesis. It will also provide some of the authors own treatment suggestions based on recognized triggering events and some suggestions for future clinical trials. PMID:24820732

  2. Caliber-Persistent Artery

    PubMed Central

    Costa, Sabrina Araújo Pinho; Ruiz, Marcelo Martinson; Kaba, Shajadi Pardo; Florezi, Giovanna Piacenza; Lemos Júnior, Celso Augusto; Witzel, Andréa Lusvarghi

    2015-01-01

    Caliber-persistent artery (CPLA) of the lip is a common vascular anomaly in which a main arterial branch extends to the surface of the mucous tissue with no reduction in its diameter. It usually manifests as pulsatile papule, is easily misdiagnosed, and is observed more frequently among older people, suggesting that its development may involve a degenerative process associated with aging; CPLA is also characterized by the loss of tone of the adjacent supporting connective tissue. Although the diagnosis is clinical, high-resolution Doppler ultrasound is a useful noninvasive tool for evaluating the lesion. This report describes the case of a 58-year-old male patient who complained of a lesion of the lower lip with bleeding and recurrent ulceration. The patient was successfully treated in our hospital after a diagnosis of CPLA and is currently undergoing a clinical outpatient follow-up with no complaints. PMID:26448884

  3. Persistent Genital Arousal Disorder

    PubMed Central

    Aswath, Manju; Pandit, Lakshmi V.; Kashyap, Karthik; Ramnath, Raguram

    2016-01-01

    Persistent genital arousal disorder (PGAD) is a phenomenon, in which afflicted women experience spontaneous genital arousal, unresolved by orgasms and triggered by sexual or nonsexual stimuli, eliciting stress. The current case is a 40-year-old female who experienced such orgasms for about a month. Physical examination, investigations, and psychological testing were noncontributory. Carbamazepine (600 mg) was discontinued due to a lack of response. She improved significantly with supportive therapy. Various neuropsychological conditions, pelvic pathology, medications, etc., have been associated with this disorder. Pharmacologic strategies have included the use of antidepressants, antipsychotics, mood stabilizers, and analgesics. Validation, psycho-education, identifying triggers, distraction techniques, and pelvic massage have been tried. Living with PGAD is very demanding. There is a lack of understanding of the problem, shame, and hesitation to seek help. The syndrome has been recently described, and understanding is still evolving. PMID:27570347

  4. Engineering persister-specific antibiotics with synergistic antimicrobial functions.

    PubMed

    Schmidt, Nathan W; Deshayes, Stephanie; Hawker, Sinead; Blacker, Alyssa; Kasko, Andrea M; Wong, Gerard C L

    2014-09-23

    Most antibiotics target growth processes and are ineffective against persister bacterial cells, which tolerate antibiotics due to their reduced metabolic activity. These persisters act as a genetic reservoir for resistant mutants and constitute a root cause of antibiotic resistance, a worldwide problem in human health. We re-engineer antibiotics specifically for persisters using tobramycin, an aminoglycoside antibiotic that targets bacterial ribosomes but is ineffective against persisters with low metabolic and cellular transport activity. By giving tobramycin the ability to induce nanoscopic negative Gaussian membrane curvature via addition of 12 amino acids, we transform tobramycin itself into a transporter sequence. The resulting molecule spontaneously permeates membranes, retains the high antibiotic activity of aminoglycosides, kills E. coli and S. aureus persisters 4-6 logs better than tobramycin, but remains noncytotoxic to eukaryotes. These results suggest a promising paradigm to renovate traditional antibiotics.

  5. Reconsidering the Relationship between Student Engagement and Persistence in College

    ERIC Educational Resources Information Center

    Hu, Shouping

    2011-01-01

    Using data from two rounds of surveys on students in the Washington State Achievers (WSA) program, this study examined the relationship between student engagement in college activities and student persistence in college. Different approaches using student engagement measures in the persistence models were compared. The results indicated that the…

  6. Epigenetic regulation of persistent pain

    PubMed Central

    Bai, Guang; Ren, Ke; Dubner, Ronald

    2014-01-01

    Persistent or chronic pain is tightly associated with various environmental changes and linked to abnormal gene expression within cells processing nociceptive signaling. Epigenetic regulation governs gene expression in response to environmental cues. Recent animal model and clinical studies indicate that epigenetic regulation plays an important role in the development/maintenance of persistent pain and, possibly the transition of acute pain to chronic pain, thus shedding light in a direction for development of new therapeutics for persistent pain. PMID:24948399

  7. Development of Persister-FACSeq: a method to massively parallelize quantification of persister physiology and its heterogeneity

    PubMed Central

    Henry, Theresa C.; Brynildsen, Mark P.

    2016-01-01

    Bacterial persisters are thought to underlie the relapse of chronic infections. Knowledge of persister physiology would illuminate avenues for therapeutic intervention; however, such knowledge has remained elusive because persisters have yet to be segregated from other cell types to sufficient purity. This technical hurdle has stymied progress toward understanding persistence. Here we developed Persister-FACSeq, which is a method that uses fluorescence-activated cell sorting, antibiotic tolerance assays, and next generation sequencing to interrogate persister physiology and its heterogeneity. As a proof-of-concept, we used Persister-FACSeq on a library of reporters to study gene expression distributions in non-growing Escherichia coli, and found that persistence to ofloxacin is inversely correlated with the capacity of non-growing cells to synthesize protein. Since Persister-FACSeq can be applied to study persistence to any antibiotic in any environment for any bacteria that can harbor a fluorescent reporter, we anticipate that it will yield unprecedented knowledge of this detrimental phenotype. PMID:27142337

  8. Inhaled nitric oxide decreases pulmonary endothelial nitric oxide synthase expression and activity in normal newborn rat lungs

    PubMed Central

    Hua-Huy, Thông; Duong-Quy, Sy; Pham, Hoa; Pansiot, Julien; Mercier, Jean-Christophe; Baud, Olivier

    2016-01-01

    Inhaled nitric oxide (iNO) is commonly used in the treatment of very ill pre-term newborns. Previous studies showed that exogenous NO could affect endothelial NO synthase (eNOS) activity and expression in vascular endothelial cell cultures or adult rat models, but this has never been fully described in newborn rat lungs. We therefore aimed to assess the effects of iNO on eNOS expression and activity in newborn rats. Rat pups, post-natal day (P) 0 to P7, and their dams were placed in a chamber containing NO at 5 ppm (iNO-5 ppm group) or 20 ppm (iNO-20 ppm group), or in room air (control group). Rat pups were sacrificed at P7 and P14 for evaluation of lung eNOS expression and activity. At P7, eNOS protein expression in total lung lysates, in bronchial and arterial sections, was significantly decreased in the iNO-20 ppm versus control group. At P14, eNOS expression was comparable among all three groups. The amounts of eNOS mRNA significantly differed at P7 between the iNO-20 ppm and control groups. NOS activity decreased in the iNO-20 ppm group at P7 and returned to normal levels at P14. There was an imbalance between superoxide dismutase and NOS activities in the iNO-20 ppm group at P7. Inhalation of NO at 20 ppm early after birth decreases eNOS gene transcription, protein expression and enzyme activity. This decrease might account for the rebound phenomenon observed in patients treated with iNO.

  9. Presence of Rheumatoid Factor during Chronic HCV Infection Is Associated with Expansion of Mature Activated Memory B-Cells that Are Hypo-Responsive to B-Cell Receptor Stimulation and Persist during the Early Stage of IFN Free Therapy

    PubMed Central

    Reyes-Avilés, Elane; Kostadinova, Lenche; Rusterholtz, Anne; Cruz-Lebrón, Angelica; Falck-Ytter, Yngve; Anthony, Donald D.

    2015-01-01

    Approximately half of those with chronic hepatitis C virus (HCV) infection have circulating rheumatoid factor (RF), and a portion of these individuals develop cryoglobulinemic vasculitis. B cell phenotype/function in relation to RF in serum has been unclear. We examined B cell subset distribution, activation state (CD86), cell cycle state (Ki67), and ex-vivo response to BCR, TLR9 and TLR7/8 stimulation, in chronic HCV-infected donors with or without RF, and uninfected donors. Mature-activated B-cells of HCV-infected donors had lower CD86 expression compared to uninfected donors, and in the presence of RF they also showed reduced CD86 expression in response to BCR and TLR9 stimulation. Additionally, mature activated memory B cells of HCV RF+ donors less commonly expressed Ki67+ than HCV RF- donors, and did not proliferate as well in response to BCR stimulation. Proportions of mature-activated B cells were enhanced, while naïve B-cells were lower in the peripheral blood of HCV-RF+ compared to RF- and uninfected donors. None of these parameters normalize by week 8 of IFN free direct acting antiviral (DAA) therapy in HCV RF+ donors, while in RF- donors, mature activated B cell proportions did normalize. These data indicate that while chronic HCV infection alone results in a lower state of activation in mature activated memory B cells, the presence of RF in serum is associated with a more pronounced state of unresponsiveness and an overrepresentation of these B cells in the blood. This phenotype persists at least during the early time window after removal of HCV from the host. PMID:26649443

  10. Pathways of Student Persistence at RSC (Includes Persistence of Matriculants).

    ERIC Educational Resources Information Center

    Fredericksen, Marlene

    In 1991, a study was conducted of semester-to-semester persistence patterns at Rancho Santiago College (RSC). The study involved tracking the attendance patterns of all RSC students entering as new students in fall 1983 and each subsequent fall until 1990; and comparing the persistence rates of matriculated and non-matriculated students in the…

  11. Emotional persistence in online chatting communities

    PubMed Central

    Garas, Antonios; Garcia, David; Skowron, Marcin; Schweitzer, Frank

    2012-01-01

    How do users behave in online chatrooms, where they instantaneously read and write posts? We analyzed about 2.5 million posts covering various topics in Internet relay channels, and found that user activity patterns follow known power-law and stretched exponential distributions, indicating that online chat activity is not different from other forms of communication. Analysing the emotional expressions (positive, negative, neutral) of users, we revealed a remarkable persistence both for individual users and channels. I.e. despite their anonymity, users tend to follow social norms in repeated interactions in online chats, which results in a specific emotional “tone” of the channels. We provide an agent-based model of emotional interaction, which recovers qualitatively both the activity patterns in chatrooms and the emotional persistence of users and channels. While our assumptions about agent's emotional expressions are rooted in psychology, the model allows to test different hypothesis regarding their emotional impact in online communication. PMID:22577512

  12. Emotional persistence in online chatting communities

    NASA Astrophysics Data System (ADS)

    Garas, Antonios; Garcia, David; Skowron, Marcin; Schweitzer, Frank

    2012-05-01

    How do users behave in online chatrooms, where they instantaneously read and write posts? We analyzed about 2.5 million posts covering various topics in Internet relay channels, and found that user activity patterns follow known power-law and stretched exponential distributions, indicating that online chat activity is not different from other forms of communication. Analysing the emotional expressions (positive, negative, neutral) of users, we revealed a remarkable persistence both for individual users and channels. I.e. despite their anonymity, users tend to follow social norms in repeated interactions in online chats, which results in a specific emotional ``tone'' of the channels. We provide an agent-based model of emotional interaction, which recovers qualitatively both the activity patterns in chatrooms and the emotional persistence of users and channels. While our assumptions about agent's emotional expressions are rooted in psychology, the model allows to test different hypothesis regarding their emotional impact in online communication.

  13. Effects of Escitalopram on a Rat Model of Persistent Stress-Altered Hedonic Activities: Towards a New Understanding of Stress and Depression.

    PubMed

    Yang, Szu-Nian; Wang, Ying-Hsiu; Tung, Che-Se; Ko, Chih-Yuan; Liu, Yia-Ping

    2015-12-31

    Chronic mild stress (CMS) paradigm is a model to simulate clinical depression induced by long-term environmental stress. The present study investigated the effects of escitalopram, a specific serotonin reuptake inhibitor (SSRI), on depression-like activities in adult (18 week-old) Sprague-Dawley (SD) rats that underwent a total 8-week CMS. Body weight, locomotor activity and sucrose consumption of the rats were measured under CMS paradigm and following escitalopram treatment. The plasma level of corticosterone was also measured at the end of the experiment. Our results revealed that the CMS program reduced the body weight, but not the locomotor activity of the rats. Adult SD rats consumed less sucrose solution under CMS. However, chronic escitalopram regime (10 mg/kg/day for 4 weeks) appeared not helpful in reversing this CMS effect and, if any, the drug exaggerated anxiety profile of the animals. Unexpectedly, the stressed rats exhibited higher sucrose consumption than non-stressed rats after receiving repeated saline injections. Further, the stressed rats were found to have a higher plasma level of corticosterone after escitalopram treatment. Our results provide an example of the possibility that previously stressed individuals may develop an anti-depression ability that lessens the benefits of intervention with antidepressants. Finally, a separate group of rats that entered the CMS program at 10 week-old were used to examine possible effects of aging to interpret the stress coping ability observed in the 18 week-old rats. The younger rats developed less anti-anhedonia effects under repeated saline injections. The data of the present study provide a different perspective on stress-induced depression and possible interaction with antidepressants. PMID:26717919

  14. Pregnancy Adaptive Programming of Capacitative Entry Responses Alters NO Output in Vascular Endothelium: New Insights Into eNOS Regulation through Adaptive Cell Signaling

    PubMed Central

    Boeldt, DS; Yi, FX; Bird, IM

    2014-01-01

    In pregnancy, vascular nitric oxide (NO) production is increased in the systemic and more so in the uterine vasculature, so supporting maximal perfusion of the uterus. This high level of functionality is matched in the umbilical vein, and in corresponding disease states such as preeclampsia, reduced vascular responses are seen in both uterine artery and umbilical vein. In any endothelial cell, NO actually produced by endothelial nitric oxide synthase (eNOS) is determined by the maximum capacity of the cell (eNOS expression levels), eNOS phosphorylation state, and the intracellular [Ca2+]i concentration in response to circulating hormones or physical forces. Herein we discuss how pregnancy specific reprogramming of NO output is determined as much by pregnancy adaptation of [Ca2+]i signaling responses as it is by eNOS expression and phosphorylation. By examining changes in [Ca2+]i signaling responses from HHVE, UAEC, and HUVEC in (where appropriate) nonpregnant, normal pregnant, and pathological pregnant (preeclamptic) state, it is clear that pregnancy adaptation of NO output occurs at the level of sustained phase ‘capacitative entry’ [Ca2+]i response, and the adapted response is lacking in preeclamptic pregnancies. Further, gap junction function is an essential permissive regulator of the capacitative response and impairment of NO output results from any inhibitor of gap junction function, or capacitative entry using TRPC channels. Identifying these [Ca2+]i signaling mechanisms underlying normal pregnancy adaptation of NO output not only provides novel targets for future treatment of diseases of pregnancy, but may also apply to other common forms of hypertension. PMID:21555345

  15. Persistent third branchial apparatus.

    PubMed

    Lin, J N; Wang, K L

    1991-06-01

    Neck sinuses, cysts or fistulae arising from the third branchial apparatus, have seldom been reported. Between 1979 and 1989, 16 cases were diagnosed as persistent third branchial apparatus based on a fistula open or in proximity to the pyriform sinus. There were 8 boys and 8 girls whose ages ranged from newborn to 13 years. Esophagogram was performed in 6; 4 showed a fistula tract leading to the pyriform sinus. Others were demonstrated at surgery. The main presentations were suppurative thyroiditis (5), lateral neck fistula (5), cyst (3), mass (1), abscess (1), and esophageal stricture (1). This was interpreted as a spectrum of disease that in the newborn may present as a cyst, and later in childhood as a fistula in the lower neck or recurrent suppurative thyroiditis if the fistula ends in the thyroid gland. It is imperative to search for this internal communication to the pyriform sinus to make a correct diagnosis and to avoid development of esophagocutaneous fistula postoperatively. With more awareness of this disease entity, the noted incidence should increase. PMID:1941452

  16. Perchance to dream? Primordial motor activity patterns in vertebrates from fish to mammals: their prenatal origin, postnatal persistence during sleep, and pathological reemergence during REM sleep behavior disorder.

    PubMed

    Corner, Michael A; Schenck, Carlos H

    2015-12-01

    An overview is presented of the literature dealing with sleep-like motility and concomitant neuronal activity patterns throughout the life cycle in vertebrates, ectothermic as well as endothermic. Spontaneous, periodically modulated, neurogenic bursts of non-purposive movements are a universal feature of larval and prenatal behavior, which in endothermic animals (i.e. birds and mammals) continue to occur periodically throughout life. Since the entire body musculature is involved in ever-shifting combinations, it is proposed that these spontaneously active periods be designated as 'rapid-BODY-movement' (RBM) sleep. The term 'rapid-EYE-movement (REM) sleep', characterized by attenuated muscle contractions and reduced tonus, can then be reserved for sleep at later stages of development. Mature stages of development in which sustained muscle atonia is combined with 'paradoxical arousal' of cortical neuronal firing patterns indisputably represent the evolutionarily most recent aspect of REM sleep, but more research with ectothermic vertebrates, such as fish, amphibians and reptiles, is needed before it can be concluded (as many prematurely have) that RBM is absent in these species. Evidence suggests a link between RBM sleep in early development and the clinical condition known as 'REM sleep behavior disorder (RBD)', which is characterized by the resurgence of periodic bouts of quasi-fetal motility that closely resemble RBM sleep. Early developmental neuromotor risk factors for RBD in humans also point to a relationship between RBM sleep and RBD.

  17. Pterostilbene, an Active Constituent of Blueberries, Stimulates Nitric Oxide Production via Activation of Endothelial Nitric Oxide Synthase in Human Umbilical Vein Endothelial Cells.

    PubMed

    Park, Seong Hoon; Jeong, Sun-Oh; Chung, Hun-Teag; Pae, Hyun-Ock

    2015-09-01

    Endothelial dysfunction, a key process in development of cardiovascular diseases, is largely due to reduced nitric oxide (NO) derived from endothelial NO synthase (eNOS). Resveratrol has been reported to stimulate NO production via estrogen receptor α (ERα) activation in endothelial cells. Here, we investigated whether two natural methylated analogs of resveratrol, pterostilbene (Pts) and trans-3,5,4'-trimethoxystilbene (TMS), similarly to resveratrol, could influence endothelial NO release in human umbilical vein endothelial cells (HUVECs). In HUVECs exposed to Pts or TMS, NO production and phosphorylation of eNOS, protein kinase B (Akt), and ERα were measured by using a fluorimetric NO assay kit and Western blot analysis, respectively. Dimethylated Pts, but not trimethylated TMS, stimulated dose-dependent NO production via eNOS phosphorylation. Pts also stimulated dose-dependent phosphorylation of Akt, but not of ERα. NO production and eNOS phosphorylation in response to Pts were significantly abolished by the phosphoinositide 3-kinase (PI3K)/Akt inhibitor LY294002, but not by the ERα antagonist ICI182780. Our results suggest that Pts, but not TMS, is capable of inducing eNOS phosphorylation and the subsequent NO release, presumably, by activating PI3K/Akt pathway. The potential efficacy of Pts, an active constituent of blueberries, may aid in the prevention of cardiovascular diseases characterized by endothelial dysfunction.

  18. Impact of Rosuvastatin Treatment on HDL-Induced PKC-βII and eNOS Phosphorylation in Endothelial Cells and Its Relation to Flow-Mediated Dilatation in Patients with Chronic Heart Failure.

    PubMed

    Winzer, Ephraim B; Gaida, Pauline; Höllriegel, Robert; Fischer, Tina; Linke, Axel; Schuler, Gerhard; Adams, Volker; Erbs, Sandra

    2016-01-01

    Background. Endothelial function is impaired in chronic heart failure (CHF). Statins upregulate endothelial NO synthase (eNOS) and improve endothelial function. Recent studies demonstrated that HDL stimulates NO production due to eNOS phosphorylation at Ser(1177), dephosphorylation at Thr(495), and diminished phosphorylation of PKC-βII at Ser(660). The aim of this study was to elucidate the impact of rosuvastatin on HDL mediated eNOS and PKC-βII phosphorylation and its relation to endothelial function. Methods. 18 CHF patients were randomized to 12 weeks of rosuvastatin or placebo. At baseline, 12 weeks, and 4 weeks after treatment cessation we determined lipid levels and isolated HDL. Human aortic endothelial cells (HAEC) were incubated with isolated HDL and phosphorylation of eNOS and PKC-βII was evaluated. Flow-mediated dilatation (FMD) was measured at the radial artery. Results. Rosuvastatin improved FMD significantly. This effect was blunted after treatment cessation. LDL plasma levels were reduced after rosuvastatin treatment whereas drug withdrawal resulted in significant increase. HDL levels remained unaffected. Incubation of HAEC with HDL had no impact on phosphorylation of eNOS or PKC-βII. Conclusion. HDL mediated eNOS and PKC-βII phosphorylation levels in endothelial cells do not change with rosuvastatin in CHF patients and do not mediate the marked improvement in endothelial function. PMID:27563480

  19. Impact of Rosuvastatin Treatment on HDL-Induced PKC-βII and eNOS Phosphorylation in Endothelial Cells and Its Relation to Flow-Mediated Dilatation in Patients with Chronic Heart Failure

    PubMed Central

    Gaida, Pauline; Höllriegel, Robert; Fischer, Tina; Linke, Axel; Schuler, Gerhard; Adams, Volker; Erbs, Sandra

    2016-01-01

    Background. Endothelial function is impaired in chronic heart failure (CHF). Statins upregulate endothelial NO synthase (eNOS) and improve endothelial function. Recent studies demonstrated that HDL stimulates NO production due to eNOS phosphorylation at Ser1177, dephosphorylation at Thr495, and diminished phosphorylation of PKC-βII at Ser660. The aim of this study was to elucidate the impact of rosuvastatin on HDL mediated eNOS and PKC-βII phosphorylation and its relation to endothelial function. Methods. 18 CHF patients were randomized to 12 weeks of rosuvastatin or placebo. At baseline, 12 weeks, and 4 weeks after treatment cessation we determined lipid levels and isolated HDL. Human aortic endothelial cells (HAEC) were incubated with isolated HDL and phosphorylation of eNOS and PKC-βII was evaluated. Flow-mediated dilatation (FMD) was measured at the radial artery. Results. Rosuvastatin improved FMD significantly. This effect was blunted after treatment cessation. LDL plasma levels were reduced after rosuvastatin treatment whereas drug withdrawal resulted in significant increase. HDL levels remained unaffected. Incubation of HAEC with HDL had no impact on phosphorylation of eNOS or PKC-βII. Conclusion. HDL mediated eNOS and PKC-βII phosphorylation levels in endothelial cells do not change with rosuvastatin in CHF patients and do not mediate the marked improvement in endothelial function. PMID:27563480

  20. Cerebral vasoconstriction reactions and plasma levels of ETBR, ET-1, and eNOS in patients with chronic high altitude disease.

    PubMed

    Wu, Shizheng; Hao, Guisheng; Zhang, Shukun; Jiang, Dongmei; Wuren, Tana; Luo, Junming

    2016-09-01

    The aim of the present study was to examine cerebral vasoconstriction in patients with chronic high altitude disease [cerebrovascular reactivity (CVR)], and to evaluate differences in alterations of brain vascular contractile reactivity of chronic mountain sickness (CMS) patients and healthy controls. Alterations of endothelin (ET) and its receptor, as well as endothelial nitric oxide synthase (eNOS) levels in the plasma were examined to determine the cerebral reservation capacities in CMS patients. Transcranial Doppler ultrasound and carbon dioxide analysis methods were used to detect the CVR variances. At the same time, enzyme‑linked immunosorbent assay approaches were utilized to detect the ET and ET B receptor and the eNOS levels in serum of the CMS patients and healthy controls. CVR and CVRI levels in CMS patients were lower than those of the healthy control subjects and the difference was statistically significant (P<0.05). By contrast, eNOS and ET‑1 levels were not statistically significant for CMS and healthy controls (P>0.05). However, the ET receptor concentration level was higher in CMS than the healthy controls. Thus, ET‑1 may not be a direct etiological variation but may play compensatory roles in CMS patients. The results of the study may provide scientific clues for the prevention and treatment of CMS with higher blood coagulation states of cerebral infarction in patients with chronic high altitude disease.

  1. Dietary soy isoflavone induced increases in antioxidant and eNOS gene expression lead to improved endothelial function and reduced blood pressure in vivo.

    PubMed

    Mahn, Katharina; Borrás, Consuelo; Knock, Greg A; Taylor, Paul; Khan, Imran Y; Sugden, David; Poston, Lucilla; Ward, Jeremy P T; Sharpe, Richard M; Viña, Jose; Aaronson, Philip I; Mann, Giovanni E

    2005-10-01

    Epidemiological evidence suggests that populations consuming large amounts of soy protein have a reduced incidence of coronary heart disease (1-5). The cardiovascular risks associated with conventional hormone replacement therapy in postmenopausal women (5-7) have precipitated a search for alternative estrogen receptor modulators. Here we report that long-term feeding of rats with a soy protein-rich (SP) diet during gestation and adult life results in decreased oxidative stress, improved endothelial function, and reduced blood pressure in vivo measured by radiotelemetry in aged male offspring. Improved vascular reactivity in animals fed an SP diet was paralleled by increased mitochondrial glutathione and mRNA levels for endothelial nitric oxide synthase (eNOS) and the antioxidant enzymes manganese superoxide dismutase and cytochrome c oxidase. Reduced eNOS and antioxidant gene expression, impaired endothelial function, and elevated blood pressure in animals fed a soy-deficient diet was reversed after refeeding them an SP diet for 6 months. Our findings suggest that an SP diet increases eNOS and antioxidant gene expression in the vasculature and other tissues, resulting in reduced oxidative stress and increased NO bioavailability. The improvement in endothelial function, increased gene expression, and reduced blood pressure by soy isoflavones have implications for alternative therapy for postmenopausal women and patients at risk of coronary heart disease.

  2. Cerebral vasoconstriction reactions and plasma levels of ETBR, ET-1, and eNOS in patients with chronic high altitude disease

    PubMed Central

    Wu, Shizheng; Hao, Guisheng; Zhang, Shukun; Jiang, Dongmei; Wuren, Tana; Luo, Junming

    2016-01-01

    The aim of the present study was to examine cerebral vasoconstriction in patients with chronic high altitude disease [cerebrovascular reactivity (CVR)], and to evaluate differences in alterations of brain vascular contractile reactivity of chronic mountain sickness (CMS) patients and healthy controls. Alterations of endothelin (ET) and its receptor, as well as endothelial nitric oxide synthase (eNOS) levels in the plasma were examined to determine the cerebral reservation capacities in CMS patients. Transcranial Doppler ultrasound and carbon dioxide analysis methods were used to detect the CVR variances. At the same time, enzyme-linked immunosorbent assay approaches were utilized to detect the ET and ET B receptor and the eNOS levels in serum of the CMS patients and healthy controls. CVR and CVRI levels in CMS patients were lower than those of the healthy control subjects and the difference was statistically significant (P<0.05). By contrast, eNOS and ET-1 levels were not statistically significant for CMS and healthy controls (P>0.05). However, the ET receptor concentration level was higher in CMS than the healthy controls. Thus, ET-1 may not be a direct etiological variation but may play compensatory roles in CMS patients. The results of the study may provide scientific clues for the prevention and treatment of CMS with higher blood coagulation states of cerebral infarction in patients with chronic high altitude disease. PMID:27485004

  3. Persistence probabilities for stream populations.

    PubMed

    Samia, Yasmine; Lutscher, Frithjof

    2012-07-01

    Individuals in streams and rivers are constantly at risk of being washed downstream and thereby lost to their population. The possibility of diffusion-mediated persistence of populations in advective environments has been the focus of a multitude of recent modeling efforts. Most of these recent models are deterministic, and they predict the existence of a critical advection velocity, above which a population cannot persist. In this work, we present a stochastic approach to the persistence problem in streams and rivers. We use the dominant eigenvalue of the advection-diffusion operator to transition from a spatially explicit description to a spatially implicit birth-death process, in which individual washout from the domain appears as an additional death term. We find that the deterministic persistence threshold is replaced by a smooth transition from almost sure persistence to extinction as advection velocity increases. More interestingly, we explore how temporal variation in flow rate and other parameters affect the persistence probability. In line with general expectations, we find that temporal variation often decreases the persistence probability, and we focus on a few examples of how variation can increase population persistence.

  4. Student Persistence in Community Colleges

    ERIC Educational Resources Information Center

    Nakajima, Mikiko A.; Dembo, Myron H.; Mossler, Ron

    2012-01-01

    The current study extends the research on student persistence in community colleges by investigating factors likely to influence a student's decision to drop out or stay in school. Specifically, this study examined demographic, financial, academic, academic integration, and psychosocial variables and their relationship to student persistence. A…

  5. Multidimensional persistence in biomolecular data

    PubMed Central

    Xia, Kelin; Wei, Guo-Wei

    2015-01-01

    Persistent homology has emerged as a popular technique for the topological simplification of big data, including biomolecular data. Multidimensional persistence bears considerable promise to bridge the gap between geometry and topology. However, its practical and robust construction has been a challenge. We introduce two families of multidimensional persistence, namely pseudo-multidimensional persistence and multiscale multidimensional persistence. The former is generated via the repeated applications of persistent homology filtration to high dimensional data, such as results from molecular dynamics or partial differential equations. The latter is constructed via isotropic and anisotropic scales that create new simiplicial complexes and associated topological spaces. The utility, robustness and efficiency of the proposed topological methods are demonstrated via protein folding, protein flexibility analysis, the topological denoising of cryo-electron microscopy data, and the scale dependence of nano particles. Topological transition between partial folded and unfolded proteins has been observed in multidimensional persistence. The separation between noise topological signatures and molecular topological fingerprints is achieved by the Laplace-Beltrami flow. The multiscale multidimensional persistent homology reveals relative local features in Betti-0 invariants and the relatively global characteristics of Betti-1 and Betti-2 invariants. PMID:26032339

  6. Multidimensional persistence in biomolecular data.

    PubMed

    Xia, Kelin; Wei, Guo-Wei

    2015-07-30

    Persistent homology has emerged as a popular technique for the topological simplification of big data, including biomolecular data. Multidimensional persistence bears considerable promise to bridge the gap between geometry and topology. However, its practical and robust construction has been a challenge. We introduce two families of multidimensional persistence, namely pseudomultidimensional persistence and multiscale multidimensional persistence. The former is generated via the repeated applications of persistent homology filtration to high-dimensional data, such as results from molecular dynamics or partial differential equations. The latter is constructed via isotropic and anisotropic scales that create new simiplicial complexes and associated topological spaces. The utility, robustness, and efficiency of the proposed topological methods are demonstrated via protein folding, protein flexibility analysis, the topological denoising of cryoelectron microscopy data, and the scale dependence of nanoparticles. Topological transition between partial folded and unfolded proteins has been observed in multidimensional persistence. The separation between noise topological signatures and molecular topological fingerprints is achieved by the Laplace-Beltrami flow. The multiscale multidimensional persistent homology reveals relative local features in Betti-0 invariants and the relatively global characteristics of Betti-1 and Betti-2 invariants.

  7. Genetic variation in MDR1, LPL and eNOS genes and the response to atorvastatin treatment in ischemic stroke.

    PubMed

    Munshi, Anjana

    2012-11-01

    Statins reduce the risk of cardiovascular events by lowering the blood cholesterol. Many genes involved in the pharmacodynamic pathway of statins have been part of pharmacogenetic research in patients with hypercholesterolemia, with an emphasis on genes involved in the cholesterol pathway. The present study was carried out with an aim to evaluate the association between the genetic variants of lipoprotein lipase gene [HindIII (+/+)/HindIII (-/-)], multiple drug resistance gene (C3435T) and endothelial nitric oxide synthase gene (4a/4b) with clinical outcome including an increased risk of recurrent stroke or death in ischemic stroke patients on atorvastatin therapy. 525 stroke patients and 500 healthy controls were involved in the study. Follow-up telephone interviews were conducted with patients post-event to determine stroke outcome. Blood samples were collected and genotypes determined by polymerase chain reaction-restriction digestion technique. A significant association of MDR1 and LPL gene variants with bad outcome in stroke patients on atorvastatin therapy was found. However, there was no significant association of 27 bp VNTR polymorphism of eNOS gene with outcome. MDR analysis was carried out to analyze gene-gene interaction involving these gene variants contributing to clinical outcome of patients on stratin therapy but no significant interaction between these variants was observed. In conclusion the individuals with HindIII (-/-) genotype of LPL and CC genotype of MDR1 gene would benefit more from atorvastatin therapy. PMID:22810051

  8. Possible role of tocopherols in the modulation of host microRNA with potential antiviral activity in patients with hepatitis B virus-related persistent infection: a systematic review.

    PubMed

    Fiorino, S; Bacchi-Reggiani, L; Sabbatani, S; Grizzi, F; di Tommaso, L; Masetti, M; Fornelli, A; Bondi, A; de Biase, D; Visani, M; Cuppini, A; Jovine, E; Pession, A

    2014-12-14

    Hepatitis B virus (HBV) infection represents a serious global health problem and persistent HBV infection is associated with an increased risk of cirrhosis, hepatocellular carcinoma and liver failure. Recently, the study of the role of microRNA (miRNA) in the pathogenesis of HBV has gained considerable interest as well as new treatments against this pathogen have been approved. A few studies have investigated the antiviral activity of vitamin E (VE) in chronic HBV carriers. Herein, we review the possible role of tocopherols in the modulation of host miRNA with potential anti-HBV activity. A systematic research of the scientific literature was performed by searching the MEDLINE, Cochrane Library and EMBASE databases. The keywords used were 'HBV therapy', 'HBV treatment', 'VE antiviral effects', 'tocopherol antiviral activity', 'miRNA antiviral activity' and 'VE microRNA'. Reports describing the role of miRNA in the regulation of HBV life cycle, in vitro and in vivo available studies reporting the effects of VE on miRNA expression profiles and epigenetic networks, and clinical trials reporting the use of VE in patients with HBV-related chronic hepatitis were identified and examined. Based on the clinical results obtained in VE-treated chronic HBV carriers, we provide a reliable hypothesis for the possible role of this vitamin in the modulation of host miRNA profiles perturbed by this viral pathogen and in the regulation of some cellular miRNA with a suggested potential anti-HBV activity. This approach may contribute to the improvement of our understanding of pathogenetic mechanisms involved in HBV infection and increase the possibility of its management and treatment.

  9. Degradation of MSCRAMM target macromolecules in VLU slough by Lucilia sericata chymotrypsin 1 (ISP) persists in the presence of tissue gelatinase activity.

    PubMed

    Pritchard, David I; Brown, Alan P

    2015-08-01

    Venous leg ulcer slough is unpleasant to the patient and difficult to manage clinically. It harbours infection, also preventing wound management materials and dressings from supporting the underlying viable tissues. In other words, slough has significant nuisance value in the tissue viability clinic. In this study, we have sought to increase our knowledge of slough by building upon a previous but limited analysis of this necrotic tissue. In particular, slough has been probed using Western blotting for the presence of proteins with the capacity to engage microbial surface components recognising adhesive matrix macromolecules. Although the samples were difficult to resolve, we detected fibrinogen, fibronectin, IgG, collagen, human serum albumin and matrix metalloproteinase-9. Furthermore, the effect of a maggot-derived debridement enzyme, chymotrypsin 1 on macromolecules in slough was confirmed across seven patient samples. The effect of chymotrypsin 1 on slough confirms our thesis that this potential debridement enzyme could be effective in removing slough along with its associated bacteria, given its observed resistance to intrinsic gelatinase activity. In summary, we believe that the data provide scientists and clinicians with further insights into the potential molecular interactions between bacteria, wound tissue and Lucilia sericata in a clinically problematic yet scientifically interesting wound ecosystem.

  10. Coupling granular activated carbon adsorption with membrane bioreactor treatment for trace organic contaminant removal: breakthrough behaviour of persistent and hydrophilic compounds.

    PubMed

    Nguyen, Luong N; Hai, Faisal I; Kang, Jinguo; Price, William E; Nghiem, Long D

    2013-04-15

    This study investigated the removal of trace organic contaminants by a combined membrane bioreactor - granular activated carbon (MBR-GAC) syst