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Sample records for leukotrienes lt b4

  1. Mass spectrometry and metabolism of leukotriene B4

    International Nuclear Information System (INIS)

    Harper, T.W.

    1985-01-01

    Leukotriene B 4 (LTB 4 ) is a potent and powerful chemotactic factor for polymorphonuclear leukocytes and has been hypothesized to play a role as a mediator of the inflammatory response. A cell free system capable of generating leukotrienes from exogenous arachidonic acid was developed using both rat basophilic leukemia cells and murine mastocytoma cells. The cell free leukotriene generating system was used to prepare leukotrienes for mass spectral studies using electron impact (EI), chemical ionization (Cl), negative ion chemical ionization (NCl) and both positive and negative ion fast atom bombardment mass spectrometry (FAB-MS). Although all of the techniques examined yielded useful information, NCl was found to be the most useful for sensitive quantitation of leukotrienes, whereas Cl and El are more useful for unambiguous structural characterization of hydroxy fatty acid leukotrienes. Investigation of the in vivo metabolism of LTB 4 in the mouse and guinea pig indicated that less than 10% of the injected radiolabel from 3 H-LTB 4 was excreted via the urine and feces. Approximately 30% of the urinary radioactivity was volatile, probably due to loss of the tritium label as water. In the monkey, approximately 10% of the injected radiolabel from 14 C-LTB 4 was excreted in the urine within 5 1/2 hours. In this study, approximately 10% of the urinary radiolabel was volatile, with a large number of unidentified non-volatile products also observed. The isolated perfused rat lung was found to rapidly metabolize leukotriene C 4 to leukotrienes D 4 and E 4 and to leukotriene C 4 sulfoxide

  2. The Role of Leukotriene B4 in Allergic Diseases

    Directory of Open Access Journals (Sweden)

    Hiroshi Ohnishi

    2008-01-01

    Full Text Available Leukotriene B4 (LTB4 is a lipid mediator with potent chemoattractant properties and that is rapidly generated from activated innate immune cells such as neutrophils, macrophages, and mast cells. Elevated levels of LTB4 have been reported in various allergic diseases and these levels have been related to disease activity and response to treatment. Recent studies using LTB4 receptor-1 (BLT1 antagonists or BLT1-deficient mice have revealed that ligation of BLT1 by LTB4 is important for the activation and recruitment of inflammatory cells including neutrophils, eosinophils, monocytes/macrophages, mast cells, dendritic cells, and more recently, effector T cells to inflamed tissues in various inflammatory diseases. The LTB4/BLT1 pathway appears to play an important role in the pathogenesis of severe persistent asthma, aspirin- and exercise-induced asthma, allergic rhinitis, and atopic dermatitis together with other mediators including cysteinyl leukotrienes, cytokines, and chemokines. LTB4 production is in general resistant to corticosteroid treatment. In fact, corticosteroids can upregulate BLT1 expression on corticosteroid-resistant inflammatory cells such as neutrophils, monocytes, and effector memory CD8+ T cells. As a result, this corticosteroid-resistant LTB4/BLT1 pathway may contribute to the development of inflammation in allergic diseases that do not respond to the introduction of corticosteroids. Inhibition of this pathway has potential therapeutic benefit in various allergic diseases that have involvement of corticosteroid-insensitivity.

  3. (3H)leukotriene B4 binding to the guinea pig spleen membranes: a rich tissue source for a high affinity leukotriene B4 receptor site

    International Nuclear Information System (INIS)

    Cheng, J.B.; Kohi, F.; Townley, R.G.

    1986-01-01

    To select a tissue rich for the high affinity leukotriene (LT)B 4 receptor site, they compared binding of 1 nM ( 3 H)LTB 4 (180 Ci/mmol) to the crude membrane preparations of guinea pig spleen, thymus, lung, uterus, bladder, brain, adrenal gland, small intestine, liver, kidney and heart. They found that the membrane preparations from spleen contained the highest binding activity per mg protein. They characterized the LTB 4 binding to the spleen preparation in detail. LTB 4 binding was rapid, reversible, stereoselective and saturable. The data from equilibrium experiments showed a linear Scatchard plot with a K/sub d/ of 1.6 nM and a binding site density of 259 fmol/mg prot. The rank order of agents competing for spleen ( 3 H)LTB 4 binding at 25 0 C was: LTB 4 (K/sub i/ = 2.8 nM) > 20-OH-LTB 4 (23 nM) > LTA 4 (48 nM) > LTA 4 methyl ester (0.13 μM) > 20-COOH-LTB 4 (> 6.6 μM) ≥ arachidonic acid (0.15 mM) similarly ordered FPL-55,712 (0.11 mM). At 4 0 C, LTB 4 (2.3 nM) competed at least 10x more effectively than 20-OH-LTB 4 (29 nM) and 20-COOH-LTB 4 (> 6.6 μM). HPLC analysis indicated that incubation of 84 ng LTB 4 with the spleen membrane at 25 0 C did not result in the formation of 20-OH-LTB 4 ( 3 H)LTB 4 receptor binding sites

  4. Carbon monoxide inhibits omega-oxidation of leukotriene B4 by human polymorphonuclear leukocytes: evidence that catabolism of leukotriene B4 is mediated by a cytochrome P-450 enzyme.

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    Shak, S; Goldstein, I M

    1984-09-17

    Carbon monoxide significantly inhibits omega-oxidation of exogenous leukotriene B4 to 20-OH-leukotriene B4 and 20-COOH-leukotriene B4 by unstimulated polymorphonuclear leukocytes as well as omega-oxidation of leukotriene B4 that is generated when cells are stimulated with the calcium ionophore, A23187. Inhibition of omega-oxidation by carbon monoxide is concentration-dependent, completely reversible, and specific. Carbon monoxide does not affect synthesis of leukotriene B4 by stimulated polymorphonuclear leukocytes or other cell functions (i.e., degranulation, superoxide anion generation). These findings suggest that a cytochrome P-450 enzyme in human polymorphonuclear leukocytes is responsible for catabolizing leukotriene B4 by omega-oxidation.

  5. The Leukotriene B4/BLT1 Axis Is a Key Determinant in Susceptibility and Resistance to Histoplasmosis

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    Secatto, Adriana; Soares, Elyara Maria; Locachevic, Gisele Aparecida; Assis, Patricia Aparecida; Paula-Silva, Francisco Wanderlei Garcia; Serezani, Carlos Henrique; de Medeiros, Alexandra Ivo; Faccioli, Lúcia Helena

    2014-01-01

    The bioactive lipid mediator leukotriene B4 (LTB4) greatly enhances phagocyte antimicrobial functions against a myriad of pathogens. In murine histoplasmosis, inhibition of the LT-generating enzyme 5-lypoxigenase (5-LO) increases the susceptibility of the host to infection. In this study, we investigated whether murine resistance or susceptibility to Histoplasma capsulatum infection is associated with leukotriene production and an enhancement of in vivo and/or in vitro antimicrobial effector function. We show that susceptible C57BL/6 mice exhibit a higher fungal burden in the lung and spleen, increased mortality, lower expression levels of 5-LO and leukotriene B4 receptor 1 (BLT1) and decreased LTB4 production compared to the resistant 129/Sv mice. Moreover, we demonstrate that endogenous and exogenous LTs are required for the optimal phagocytosis of H. capsulatum by macrophages from both murine strains, although C57BL/6 macrophages are more sensitive to the effects of LTB4 than 129/Sv macrophages. Therefore, our results provide novel evidence that LTB4 production and BLT1 signaling are required for a histoplasmosis-resistant phenotype. PMID:24465479

  6. Development of a sensitive and specific radioreceptor assay for leukotriene B4

    International Nuclear Information System (INIS)

    Kohi, F.; Agrawal, D.K.; Cheng, J.B.; Bewtra, A.; Townley, R.G.; Olesch, J.W.

    1988-01-01

    To establish a simple and sensitive quantitation of leukotriene B 4 (LTB 4 ), they developed a radioreceptor assay (RRA) using a highly specific [ 3 H]leukotriene B 4 ([ 3 H]LTB 4 ) binding to a guinea pig spleen homogenate. The assay detected LTB 4 levels as low as 0.12 pmol per tube. 50% inhibition of bound [ 3 H]LTB 4 was obtained by 2.5 nM of unlabeled LTB 4 . [ 3 H]LTB 4 competition studies indicated that 20-hydroxy-LTB 4 was 8 times, 6 trans-LTB 4 was 640 times and 20-carboxy-LTB 4 was 1000 times less effective than LTB 4 . The peptide leukotrienes C 4 , D 4 and E 4 showed no effect on [ 3 H]LTB 4 binding. Recovery rates averaged 97% after ethanol extraction and evaporation of known amounts of LTB 4 . The intra-assay coefficients of variation for three samples were 2.4%, 7.2% and 8.4%, respectively. This assay was validated by measuring LTB 4 released from human granulocytes stimulated with calcium ionophore A23187. The LTB 4 level was maximal at 10 min and decreased rapidly after 15 min. This radioreceptor assay for leukotriene B 4 is highly sensitive and is comparable to the reported sensitivity by radioimmunoassay. The method is simpler and less expensive than other methods such as high pressure liquid chromatography and is suitable for routine measurement of leukotriene B 4

  7. Verification of the production of peptide leukotrienes (LT) in traumatic shock

    International Nuclear Information System (INIS)

    Hock, C.E.; Craft, D.V.; Lefer, D.J.; Lefer, A.M.

    1986-01-01

    Both lipoxygenase inhibition and leukotriene receptor antagonism have been demonstrated to provide significant protection in traumatic shock. Despite these findings, leukotrienes have not been found in circulating blood in Noble-Collip drum induced traumatic shock using radioimmunoassay techniques. Anesthetized rats subjected to Noble-Collip drum trauma developed a shock state characterized by a significant reduction in mean arterial blood pressure, a 4.5 fold increase in plasma cathepsin D activity, a 3-fold increase in myocardial depressant factor activity and a mean survival time of 1.9 +/- 0.3 hours. Plasma and bile samples were analyzed by reverse phase high pressure liquid chromatography to determine LT production in this shock model. No detectable peptide leukotrienes or their metabolites were found in plasma. The major peptide leukotriene from bile eluted between LTC 4 and LTD 4 and corresponds to a metabolite of LTE 4 , N-acetyl-LTE 4 . This metabolite increased from 6 +/- 3 to 41 +/- 4 units in traumatic shock when compared to sham trauma (p 4 , LTD 4 and LTE 4 (10 μg/kg/h) also resulted in the metabolism of > 90% of the parent LT to this metabolite in bile. Therefore, plasma LTs accumulate in the bile following trauma in rats. Moreover, LTC 4 , LTD 4 and LTE 4 apparently are rapidly metabolized to N-acetyl LTE 4 . These findings further support a role for leukotrienes in the pathogenesis of traumatic shock in rats

  8. Stereoselective semi-hydrogenation and deuteration of a diacetylenic precursor of leukotriene B4 methyl ester

    International Nuclear Information System (INIS)

    Pontikis, R.; Le Merrer, Y.; Depezay, J.-C.; Petillot, Y.; Rousseau, B.; Beaucourt, J.P.

    1990-01-01

    [6,7,14,15- 2 H4]-Leukotriene B4 methyl ester was prepared by reduction with deuterium gas of a suitable precursor (deuterium incorporation > 90%). Several catalytic semi-hydrogenations were affected in order to determine the best conditions for the labeling step. (author)

  9. Liquid chromatography/mass spectrometry analysis of exhaled leukotriene B4 in asthmatic children

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    Barnes Peter J

    2005-10-01

    Full Text Available Abstract Background The role of leukotriene (LT B4, a potent inflammatory mediator, in atopic asthmatic and atopic nonasthmatic children is largely unknown. The lack of a gold standard technique for measuring LTB4 in exhaled breath condensate (EBC has hampered its quantitative assessment in this biological fluid. We sought to measure LTB4 in EBC in atopic asthmatic children and atopic nonasthmatic children. Exhaled nitric oxide (NO was measured as an independent marker of airway inflammation. Methods Fifteen healthy children, 20 atopic nonasthmatic children, 25 steroid-naïve atopic asthmatic children, and 22 atopic asthmatic children receiving inhaled corticosteroids were studied. The study design was of cross-sectional type. Exhaled LTB4 concentrations were measured using liquid chromatography/mass spectrometry-mass spectrometry (LC/MS/MS with a triple quadrupole mass spectrometer. Exhaled NO was measured by chemiluminescence with a single breath on-line method. LTB4 values were expressed as the total amount (in pg of eicosanoid expired in the 15-minute breath test. Kruskal-Wallis test was used to compare groups. Results Compared with healthy children [87.5 (82.5–102.5 pg, median and interquartile range], exhaled LTB4 was increased in steroid-naïve atopic asthmatic [255.1 (175.0–314.7 pg, p 4 than steroid-naïve asthmatics [125.0 (25.0–245.0 pg vs 255.1 (175.0–314.7 pg, p Conclusion In contrast to exhaled NO concentrations, exhaled LTB4 values are selectively elevated in steroid-naïve atopic asthmatic children, but not in atopic nonasthmatic children. Although placebo control studies are warranted, inhaled corticosteroids seem to reduce exhaled LTB4 in asthmatic children. LC/MS/MS analysis of exhaled LTB4 might provide a non-invasive, sensitive, and quantitative method for airway inflammation assessment in asthmatic children.

  10. Sesquiterpene glucosides from anti-leukotriene B4 release fraction of Taraxacum officinale.

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    Kashiwada, Y; Takanaka, K; Tsukada, H; Miwa, Y; Taga, T; Tanaka, S; Ikeshiro, Y

    2001-01-01

    Chemical examination of the MeOH extract of the root of Taraxacum officinale, which exhibited inhibitory activity on the formation of leukotriene B4 from activated human neutrophils, has resulted in the isolation of 14-O-beta-D-glucosyl-11,13-dihydro-taraxinic acid (1) and 14-O-beta-D-glucosyl-taraxinic acid (2). The absolute stereostructure of 1 has been established by X-ray chrystallographic examination.

  11. Leukotriene B4leukotriene B4 receptor axis promotes oxazolone-induced contact dermatitis by directing skin homing of neutrophils and CD8+ T cells

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    Lv, Jiaoyan; Zou, Linlin; Zhao, Lina; Yang, Wei; Xiong, Yingluo; Li, Bingji; He, Rui

    2015-01-01

    Leukotriene B4 (LTB4) is a lipid mediator that is rapidly generated in inflammatory sites, and its functional receptor, BLT1, is mostly expressed on immune cells. Contact dermatitis is a common inflammatory skin disease characterized by skin oedema and abundant inflammatory infiltrates, primarily including neutrophils and CD8+ T cells. The role of the LTB4–BLT1 axis in contact dermatitis remains largely unknown. In this study, we found up-regulated gene expression of 5-lipoxygenase and leukotriene A4 hydrolase, two critical enzymes for LTB4 synthesis, BLT1 and elevated LTB4 levels in skin lesions of oxazolone (OXA)-induced contact dermatitis. BLT1 deficiency or blockade of LTB4 and BLT1 by the antagonists, bestatin and U-75302, respectively, in the elicitation phase caused significant decreases in ear swelling and skin-infiltrating neutrophils and CD8+ T cells, which was accompanied by significantly reduced skin expression of CXCL1, CXCL2, interferon-γ and interleukin-1β. Furthermore, neutrophil depletion during the elicitation phase of OXA-induced contact dermatitis also caused significant decreases in ear swelling and CD8+ T-cell infiltration accompanied by significantly decreased LTB4 synthesis and gene expression of CXCL2, interferon-γ and interleukin-1β. Importantly, subcutaneous injection of exogenous LTB4 restored the skin infiltration of CD8+ T cells in neutrophil-depleted mice following OXA challenge. Collectively, our results demonstrate that the LTB4–BLT1 axis contributes to OXA-induced contact dermatitis by mediating skin recruitment of neutrophils, which are a major source of LTB4 that sequentially direct CD8+ T-cell homing to OXA-challenged skin. Hence, LTB4 and BLT1 could be potential therapeutic targets for the treatment of contact dermatitis. PMID:25959240

  12. A radiochemical assay for detection of leukotriene B4 production from isolated cells

    International Nuclear Information System (INIS)

    Aharony, D.; Dobson, P.; Krell, R.D.

    1984-01-01

    A radiochemical procedure for quantitating the effect of inhibitors of leukotriene B4 (LTB4) biosynthesis is described. Rat peritoneal cells were labeled with 3 H-arachidonic acid and stimulated with the calcium ionophore A23187. 3 H-LTB4 was isolated by processing on C18-Sep Pak cartridges followed by reverse-phase high pressure liquid chromatography (HPLC). The identity of this product, as well as other arachidonic acid metabolites, was verified by using silicic acid column chromatography followed by straight-phase HPLC and thin layer chromatography. Using this assay, LTB4 release by ionophore A23187 has been shown to be both time- and concentration-dependent. Indomethacin enhanced, while NDGA and ETYA inhibited, the A23187-induced production of LTB4. This procedure is both simple and direct and is capable of assessing the ability of novel compounds to alter LTB4 production

  13. Leukotriene B4-Neutrophil Elastase Axis Drives Neutrophil Reverse Transendothelial Cell Migration In Vivo

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    Colom, Bartomeu; Bodkin, Jennifer V.; Beyrau, Martina; Woodfin, Abigail; Ody, Christiane; Rourke, Claire; Chavakis, Triantafyllos; Brohi, Karim; Imhof, Beat A.; Nourshargh, Sussan

    2015-01-01

    Summary Breaching endothelial cells (ECs) is a decisive step in the migration of leukocytes from the vascular lumen to the extravascular tissue, but fundamental aspects of this response remain largely unknown. We have previously shown that neutrophils can exhibit abluminal-to-luminal migration through EC junctions within mouse cremasteric venules and that this response is elicited following reduced expression and/or functionality of the EC junctional adhesion molecule-C (JAM-C). Here we demonstrate that the lipid chemoattractant leukotriene B4 (LTB4) was efficacious at causing loss of venular JAM-C and promoting neutrophil reverse transendothelial cell migration (rTEM) in vivo. Local proteolytic cleavage of EC JAM-C by neutrophil elastase (NE) drove this cascade of events as supported by presentation of NE to JAM-C via the neutrophil adhesion molecule Mac-1. The results identify local LTB4-NE axis as a promoter of neutrophil rTEM and provide evidence that this pathway can propagate a local sterile inflammatory response to become systemic. PMID:26047922

  14. Leukotriene B4-Neutrophil Elastase Axis Drives Neutrophil Reverse Transendothelial Cell Migration In Vivo.

    Science.gov (United States)

    Colom, Bartomeu; Bodkin, Jennifer V; Beyrau, Martina; Woodfin, Abigail; Ody, Christiane; Rourke, Claire; Chavakis, Triantafyllos; Brohi, Karim; Imhof, Beat A; Nourshargh, Sussan

    2015-06-16

    Breaching endothelial cells (ECs) is a decisive step in the migration of leukocytes from the vascular lumen to the extravascular tissue, but fundamental aspects of this response remain largely unknown. We have previously shown that neutrophils can exhibit abluminal-to-luminal migration through EC junctions within mouse cremasteric venules and that this response is elicited following reduced expression and/or functionality of the EC junctional adhesion molecule-C (JAM-C). Here we demonstrate that the lipid chemoattractant leukotriene B4 (LTB4) was efficacious at causing loss of venular JAM-C and promoting neutrophil reverse transendothelial cell migration (rTEM) in vivo. Local proteolytic cleavage of EC JAM-C by neutrophil elastase (NE) drove this cascade of events as supported by presentation of NE to JAM-C via the neutrophil adhesion molecule Mac-1. The results identify local LTB4-NE axis as a promoter of neutrophil rTEM and provide evidence that this pathway can propagate a local sterile inflammatory response to become systemic. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  15. Prostaglandin E2/leukotriene B4 balance induced by Lutzomyia longipalpis saliva favors Leishmania infantum infection.

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    Araújo-Santos, Théo; Prates, Deboraci Brito; França-Costa, Jaqueline; Luz, Nívea F; Andrade, Bruno B; Miranda, José Carlos; Brodskyn, Claudia I; Barral, Aldina; Bozza, Patrícia T; Borges, Valéria Matos

    2014-12-20

    Eicosanoids and sand fly saliva have a critical role in the Leishmania infection. Here, we evaluated the effect of Lutzomyia longipalpis salivary gland sonicate (SGS) on neutrophil and monocyte recruitment and activation of eicosanoid production in a murine model of inflammation. C57BL/6 mice were inoculated intraperitonealy with Lutzomyia longipalpis SGS or Leishmania infantum or both, followed by analyses of cell recruitment, parasite load and eicosanoid production. Intraperitoneal injection of Lutzomyia longipalpis SGS together with Leishmania infantum induced an early increased parasite viability in monocytes and neutrophils. L. longipalpis SGS increased prostaglandin E2 (PGE2), but reduced leukotriene B4 (LTB4) production ex vivo in peritoneal leukocytes. In addition, the pharmacological inhibition of cyclooxygenase 2 (COX-2) with NS-398 decreased parasite viability inside macrophages during Leishmania infection in the presence of L. longipalpis SGS arguing that PGE2 production is associated with diminished parasite killing. These findings indicate that L. longipalpis SGS is a critical factor driving immune evasion of Leishmania through modulation of PGE2/LTB4 axis, which may represent an important mechanism on establishment of the infection.

  16. A study of the photodegradation of leukotriene B4 by ultraviolet irradiation (UVB, UVA)

    International Nuclear Information System (INIS)

    Millar, B.; Green, C.; Ferguson, J.; Raffle, E.J.; Macleod, T.M.

    1989-01-01

    In view of the presence of the polymorphonuclear leukocyte (PMN) chemoattractant Leukotriene B 4 (LTB 4 ) in surface scale of the psoriatic lesion and the known therapeutic effect of phototherapy in psoriasis, the photostability of LTB 4 was investigated. LTB 4 was irradiated with UVB (290-320 nm) from 100-1500 mJ cm -2 and UVA (320-400 nm) from 5-40 J cm -2 . Topical application of UVB irradiated LTB 4 to forearm skin of normal volunteers showed marked reduction in cutaneous erythema, paralleled by reduced transepidermal PMN migration compared with sites of application of unirradiated and UVA irradiated LTB 4 . High performance liquid chromatography (HPLC) demonstrated a dose-dependent photodegradation of LTB 4 by UVB irradiation. UVA irradiation produced no such effect. The wavelengths responsible lie within the absorption spectrum of LTB 4 . In vitro chemotaxis studies, using an under agarose technique, showed a statistically significant reduction in the migration of PMN from psoriatic and non-psoriatic subjects to the UVB irradiated LTB 4 compared with unirradiated LTB 4 , whilst UVA irradiated LTB 4 produced a normal PMN chemotactic response. (author)

  17. Leukotriene B4 omega-hydroxylase in human polymorphonuclear leukocytes. Suicidal inactivation by acetylenic fatty acids.

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    Shak, S; Reich, N O; Goldstein, I M; Ortiz de Montellano, P R

    1985-10-25

    Human polymorphonuclear leukocytes (PMN) not only generate and respond to leukotriene B4 (LTB4), but also catabolize this mediator of inflammation rapidly and specifically by omega-oxidation (probably due to the action of a cytochrome P-450 enzyme). To develop pharmacologically useful inhibitors of the LTB4 omega-hydroxylase in human PMN, we devised a general scheme for synthesizing terminal acetylenic fatty acids based on the "acetylenic zipper" reaction. We found that the LTB4 omega-hydroxylase in intact PMN and in PMN sonicates is inactivated in a concentration-dependent fashion by terminal acetylenic analogues of lauric, palmitic, and stearic acids (i.e. 11-dodecynoic, 15-hexadecynoic, and 17-octadecynoic acids). Consistent with a suicidal process, inactivation of the LTB4 omega-hydroxylase requires molecular oxygen and NADPH, is time-dependent, and follows pseudo-first-order kinetics. Inactivation of the omega-hydroxylase by acetylenic fatty acids also is dependent on the terminal acetylenic moiety and the carbon chain length. Saturated fatty acids lacking a terminal acetylenic moiety do not inactivate the omega-hydroxylase. In addition, the two long-chain (C16, C18) acetylenic fatty acids inactivate the omega-hydroxylase at much lower concentrations (less than 5.0 microM) than those required for inactivation by the short-chain (C12) terminal acetylenic fatty acid (100 microM). Potent suicidal inhibitors of the LTB4 omega-hydroxylase in human PMN will help elucidate the roles played by LTB4 and its omega-oxidation products in regulating PMN function and in mediating inflammation.

  18. Metabolism of leukotriene B4 to dihydro and dihydro-oxo products by porcine leukocytes

    International Nuclear Information System (INIS)

    Powell, W.S.; Gravelle, F.

    1989-01-01

    Porcine leukocytes contain a novel pathway for the metabolism of leukotriene B4 (LTB4) which results in reduction of the conjugated triene chromophore to a conjugated diene. These cells converted LTB4 to two major metabolites, both of which exhibited maximal absorbance at 230 nm in their UV spectra. These products were purified by high pressure liquid chromatography and identified as 10, 11-dihydro-LTB4 and 10,11-dihydro-12-oxo-LTB4 on the basis of the mass spectra of various derivatives. The position of the double bond of LTB4 which had been reduced was established by cleaving the remaining double bonds of 10, 11-dihydro-LTB4 with ozone followed by oxidation or reduction of the resulting ozonide and analysis of the products by mass spectrometry. Experiments with deuterium-labeled substrate indicated that LTB4 could be directly converted to 10, 11-dihydro-LTB4 without the prior oxidation of either of its hydroxyl groups, as is required for the formation of dihydro metabolites of prostaglandins. Incubation of porcine leukocytes with 10, 11-dihydro-LTB4 and 10, 11-dihydro-12-oxo-LTB4 indicated that these two products can be interconverted and are in equilibrium with one another. The dihydro-oxo metabolite can therefore be formed from 10, 11-dihydro-LTB4, although we have not ruled out the possibility that it is also produced via 12-oxo-LTB4, which could be a transitory intermediate. These results indicate that porcine leukocytes contain a novel reductase/dehydrogenase pathway distinct from the pathway responsible for the metabolism of prostaglandins. This pathway is also different from the pathway in human polymorphonuclear leukocytes which converts 6-trans-isomers of LTB4 to dihydro products, since the latter pathway involves 5-oxo intermediates and results in a shift in the positions of the remaining double bonds

  19. Tritium-labelled leukotriene B4 binding to the guinea-pig spleen membrane preparation: a rich tissue source for a high-affinity leukotriene B4 receptor site

    International Nuclear Information System (INIS)

    Cheng, J.B.; Cheng, E.I.; Kohi, F.; Townley, R.G.

    1986-01-01

    Intact human granulocytes contain a leukotriene (LT) B4 receptor binding site, but the limited supply of these cells could adversely affect further progress of the study of this receptor. To select a tissue homogenate rich for this site, we have characterized the binding of highly specific [ 3 H]LTB4 to guinea-pig spleen membranes and we have determined the ability of LTB4 to compete with [ 3 H]LTB4 for binding sites in the membranes of 10 nonspleen tissues. In the spleen membrane, MgCl2 and CaCl2 enhanced [ 3 H]LTB4 binding, but NaCl and KCl decreased it. Spleen [ 3 H] LTB4 binding was a function of protein concentration and was rapid, reversible, stereoselective and saturable. Kinetic analyses showed that the rate constant for association and dissociation at 25 0 C was 0.47 nM-1 min-1 and 0.099 min-1, respectively. A Scatchard plot of the data of the equilibrium experiment resulted a straight line with a dissociation constant of 1.8 nM and a density of 274 fmol/mg of protein. Moreover, the LTB4/[ 3 H]LTB4 competition study performed at 4 or 25 0 C revealed the inhibitory constant (Ki) of LTB4 to be in the nanomolar range. The rank order of agents competing for spleen [ 3 H]LTB4 binding was: LTB4 (Ki = 2.8 nM) greater than 20-hydroxy-LTB4 (23 nM) greater than LTA4 (48 nM) greater than LTA4 methyl ester (0.13 microM) greater than 20-carboxy-LTB4 (greater than 6.6 microM) greater than or equal to arachidonic acid (0.15mM) = FPL-55,712 and FPL-57,231 (0.1-0.2 mM). Competition studies further indicated that felodipine, a 1,4-dihyropyridine Ca++ channel blocker, exhibited micromolar inhibition of spleen [ 3 H]LTB4 binding

  20. Esculetin reduces leukotriene B4 level in plasma of rats with adjuvant-induced arthritis

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    Przemysław Rzodkiewicz

    2016-10-01

    Full Text Available Objectives : Esculetin (6,7-dihydroxycoumarin is a natural coumarin with anti-oxidant, anti-inflammatory and anti-nociceptive activity. It acts as a potent inhibitor of lipoxygenases (5-LOX and 12-LOX and decreases the production of matrix metalloproteinases (MMP-1, MMP-3 and MMP-9. Because both inhibition of lipoxygenases and inhibition of matrix metalloproteinases are effective strategies in the treatment of rheumatoid arthritis, we investigated whether esculetin may be effective in adjuvant-induced arthritis in rats. Material and methods : The study was performed on male Lewis rats, in the adjuvant-induced arthritis model. Rats were divided into two groups: control (treated with 1% methylcellulose and experimental (treated with esculetin – 10 mg/kg ip.. The tested compound was administered for 5 consecutive days starting on the 21st day after induction of arthritis. Each group consisted of 7 animals. After 5 days of treatment, rats were anesthetized. The concentration of leukotriene B4 (LTB4 in plasma was determined by a competitive enzyme immunoassay. Results : The LTB4 level in plasma of rats with adjuvant-induced arthritis is increased in comparison to rats without inflammation (362 ±34 vs. 274 ±15 pg/ml, p < 0.01, respectively. Five-day treatment with esculetin in adjuvant-induced arthritis rats decreases the LTB4 level to a level comparable with rats without inflammation (284 ±23 pg/ml, p < 0.01. Conclusions : LTB4 is the most potent chemotactic agent influencing neutrophil migration into the joint. It is known that its level in serum of patients with active rheumatoid arthritis is increased and correlates with disease severity. Some other lipoxygenase inhibitors have already been tested as potential drug candidates in clinical and preclinical trials for rheumatoid arthritis (Zileuton, PF-4191834. Because esculetin decreases the LTB4 level in plasma of rats in adjuvant-induced arthritis, it may also be considered as an attractive

  1. The Role of PPAR Receptors and Leukotriene B4 Receptors in Mediating the Effects of LY293111 in Pancreatic Cancer

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    Thomas E. Adrian

    2008-01-01

    Full Text Available Pancreatic cancer is a devastating disease in which current therapies are inadequate. Separate lines of research have identified the 5-lipoxygenase/leukotriene B4 receptor pathway and the PPAR pathway as potential targets for prevention or treatment of this disease. LY293111 was originally designed as a potent leukotriene B4 receptor antagonist for treatment of inflammatory conditions. LY293111 was also known to have inhibitory effects on 5-lipoxygenase, which is upstream of the production of leukotrienes. LY293111 was shown to have potent anticancer effects in pancreatic cancer and several other solid malignancies, where it caused cell cycle arrest and marked apoptosis. Subsequently, it came to light that LY293111 exhibited PPAR agonist activity in addition to its effects on the 5-lipoxygenase pathway. This raises the question of which of the two targets is of greatest importance with regard to the anticancer effects of this agent. The evidence to date is not conclusive, but suggests that the effects of LY293111 may be mediated by both LTB4 receptors and PPAR.

  2. Control of polyclonal immunoglobulin production from human lymphocytes by leukotrienes; leukotriene B4 induces an OKT8(+), radiosensitive suppressor cell from resting, human OKT8(-) T cells

    International Nuclear Information System (INIS)

    Atluru, D.; Goodwin, J.S.

    1984-01-01

    We report that leukotriene B4 (LTB4), a 5-lipoxygenase metabolite of arachidonic acid, is a potent suppressor of polyclonal Ig production in pokeweed mitogen (PWM)-stimulated cultures of human peripheral blood lymphocytes, while LTC4 and LTD4 have little activity in this system. Preincubation of T cells with LTB4 in nanomolar to picomolar concentrations rendered these cells suppressive of Ig production in subsequent PWM-stimulated cultures of fresh, autologous B + T cells. This LTB4-induced suppressor cell was radiosensitive, and its generation could be blocked by cyclohexamide but not by mitomycin C. The LTB4-induced suppressor cell was OKT8(+), while the precursor for the cell could be OKT8(-). The incubation of OKT8(-) T cells with LTB4 for 18 h resulted in the appearance of the OKT8(+) on 10-20% of the cells, and this could be blocked by cyclohexamide but not by mitomycin C. Thus, LTB4 in very low concentrations induces a radiosensitive OKT8(+) suppressor cell from OKT8(-) cells. In this regard, LTB4 is three to six orders of magnitude more potent than any endogenous hormonal inducer of suppressor cells previously described. Glucocorticosteroids, which block suppressor cell induction in many systems, may act by inhibiting endogenous production of LTB4

  3. Omega-oxidation is the major pathway for the catabolism of leukotriene B4 in human polymorphonuclear leukocytes.

    Science.gov (United States)

    Shak, S; Goldstein, I M

    1984-08-25

    Leukotriene B4 (LTB4), formed by the 5-lipoxygenase pathway in human polymorphonuclear leukocytes (PMN), may be an important mediator of inflammation. Recent studies suggest that human leukocytes can convert LTB4 to products that are less biologically active. To examine the catabolism of LTB4, we developed (using high performance liquid chromatography) a sensitive, reproducible assay for this mediator and its omega-oxidation products (20-OH- and 20-COOH-LTB4). With this assay, we have found that human PMN (but not human monocytes, lymphocytes, or platelets) convert exogenous LTB4 almost exclusively to 20-OH- and 20-COOH-LTB4 (identified by gas chromatography-mass spectrometry). Catabolism of exogenous LTB4 by omega-oxidation is rapid (t1/2 approximately 4 min at 37 degrees C in reaction mixtures containing 1.0 microM LTB4 and 20 X 10(6) PMN/ml), temperature-dependent (negligible at 0 degrees C), and varies with cell number as well as with initial substrate concentration. The pathway for omega-oxidation in PMN is specific for LTB4 and 5(S),12(S)-dihydroxy-6,8,10,14-eicosatetraenoic acid (only small amounts of other dihydroxylated-derivatives of arachidonic acid are converted to omega-oxidation products). Even PMN that are stimulated by phorbol myristate acetate to produce large amounts of superoxide anion radicals catabolize exogenous leukotriene B4 primarily by omega-oxidation. Finally, LTB4 that is generated when PMN are stimulated with the calcium ionophore, A23187, is rapidly catabolized by omega-oxidation. Thus, human PMN not only generate and respond to LTB4, but also rapidly and specifically catabolize this mediator by omega-oxidation.

  4. Modulation of the heterogeneous membrane potential response of neutrophils to N-formyl-methionyl-leucyl-phenylalanine (FMLP) by leukotriene B4: evidence for cell recruitment

    International Nuclear Information System (INIS)

    Fletcher, M.P.

    1986-01-01

    Individual human neutrophils (PMN) isolated by Hypaque-Ficoll gradient sedimentation, dextran sedimentation, or buffy coat preparation were assessed for the effects of leukotriene B4 (5S,12R dihydroxy 6,14-cis-8, 10 trans eicosatetraenoic acid (LTB4)-pretreatment on N-formylmethionyl-leucyl-phenylalanine (FMLP)-mediated membrane potential or oxidative responses by using flow cytometry and a lipophilic probe of membrane potential (di-pentyl-oxacarbocyanine, di-O-C(5)3), or the nitroblue tetrazolium dye (NBT) reduction test, respectively. Although exposure to LTB4 (10(-7) M) had no effect on the membrane potential of resting PMN and little effect on oxidant production, pretreating PMN with LTB4 followed by FMLP (10(-6) M) demonstrated a significant enhancement in the proportion of depolarizing PMN over that seen with FMLP alone (p = 0.0014, N = 9). This recruitment of previously unresponsive cells by LTB4 was dose and time dependent, with the maximal relative increase in the proportion of depolarizing cells occurring at LTB4 concentrations of 10(-8) to 10(-7) M and within 1 min of LTB4 addition. The recruitment effect persisted despite vigorous washing of the cells. LTB4 also increased the proportion of NBT-positive PMN in response to FMLP. Although LTB4 alone did not depolarize PMN it did induce a light scatter shift indicative of cell activation. 3 H-FMLP binding studied at 0 degree C comparing buffer and LTB4-treated PMN indicated no significant change in the number or affinity of FMLP binding. The data provide evidence for the recruitment of a greater proportion of cells into a FMLP-responsive state as a mechanism for the enhanced functional response of PMN pretreated with LTB4, as well as for a dissociation of the membrane potential and light scattering responses of cells to this pro-inflammatory LT

  5. Hypercholesterolemia Increases the Production of Leukotriene B4 in Neutrophils by Enhancing the Nuclear Localization of 5-Lipoxygenase

    Directory of Open Access Journals (Sweden)

    Xiao-Feng Lai

    2014-11-01

    Full Text Available Aims: Neutrophils can synthesize leukotriene B4 (LTB4 by activating the 5-lipoxygenase (5-LOsignaling pathway. LTB4 is a pro-inflammatory mediator associated with the etiology and progression of atherosclerosis. It can increase function and number of neutrophils in an autocrine manner. Since hypercholesterolemia is associated with an increase in the number and function of neutrophils, we hypothesized that this effect could be mediated through increased production of LTB4 in neutrophils. Methods/Results: Hypercholesterolemia was modeled in Wistar rats by feeding them with a high cholesterol diet. The induction of hypercholesterolemia caused an increase in the plasma levels of LTB4, following lipopolysaccharide stimulation. This effect was recapitulated in vitro, both in the presence and absence of stimulation with the activator of 5-LO, A23187. Neutrophils in hypercholesterolemia rats expressed similar total levels of 5-LO as control rats, but displayed increased nuclear localization of 5-LO, as well as elevated levels of phosphorylated 5-LO and ERK1/2. In vitro, MβCD/cholesterol complexes enriched cholesterol in neutrophils, resulted in similar changes in 5-LO/LTB4. In addition, these alterations could be inhibited with the ERK inhibitor PD98059. Conclusion: Hypercholesterolemia increases LTB4 production in neutrophils by increasing the nuclear localization of 5-LO, which is the result of its phosphorylation by activated ERK1/2.

  6. Evidence for eosinophil recruitment, leukotriene B4 production and mast cell hyperplasia following Toxocara canis infection in rats

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    D. Carlos

    2011-04-01

    Full Text Available It is well known that eosinophilia is a key pathogenetic component of toxocariasis. The objective of the present study was to determine if there is an association between peritoneal and blood eosinophil influx, mast cell hyperplasia and leukotriene B4 (LTB4 production after Toxocara canis infection. Oral inoculation of 56-day-old Wistar rats (N = 5-7 per group with 1000 embryonated eggs containing third-stage (L3 T. canis larvae led to a robust accumulation of total leukocytes in blood beginning on day 3 and peaking on day 18, mainly characterized by eosinophils and accompanied by higher serum LTB4 levels. At that time, we also noted increased eosinophil numbers in the peritoneal cavity. In addition, we observed increased peritoneal mast cell number in the peritoneal cavity, which correlated with the time course of eosinophilia during toxocariasis. We also demonstrated that mast cell hyperplasia in the intestines and lungs began soon after the T. canis larvae migrated to these compartments, reaching maximal levels on day 24, which correlated with the complete elimination of the parasite. Therefore, mast cells appear to be involved in peritoneal and blood eosinophil infiltration through an LTB4-dependent mechanism following T. canis infection in rats. Our data also demonstrate a tight association between larval migratory stages and intestinal and pulmonary mast cell hyperplasia in the toxocariasis model.

  7. Leukotriene B4 omega-hydroxylase in human polymorphonuclear leukocytes. Partial purification and identification as a cytochrome P-450.

    Science.gov (United States)

    Shak, S; Goldstein, I M

    1985-09-01

    Human polymorphonuclear leukocytes (PMN) not only synthesize and respond to leukotriene B4 (LTB4), but also catabolize this mediator of inflammation rapidly and specifically by omega-oxidation. To characterize the enzyme(s) responsible for omega-oxidation of LTB4, human PMN were disrupted by sonication and subjected to differential centrifugation to yield membrane, granule, and cytosol fractions (identified by biochemical markers). LTB4 omega-hydroxylase activity was concentrated (together with NADPH cytochrome c reductase activity) only in the membrane fraction (specific activity increased 10-fold as compared to whole sonicates, 41% recovery). Negligible activity was detected in granule or cytosol fractions. LTB4 omega-hydroxylase activity in isolated PMN membranes was linear with respect to duration of incubation and protein concentration, was maximal at pH 7.4, had a Km for LTB4 of 0.6 microM, and was dependent on oxygen and on reduced pyridine nucleotides (apparent Km for NADPH = 0.5 microM; apparent Km for NADH = 223 microM). The LTB4 omega-hydroxylase was inhibited significantly by carbon monoxide, ferricytochrome c, SKF-525A, and Triton X-100, but was not affected by alpha-naphthoflavone, azide, cyanide, catalase, and superoxide dismutase. Finally, isolated PMN membranes exhibited a carbon monoxide difference spectrum with a peak at 452 nm. Thus, we have partially purified the LTB4 omega-hydroxylase in human PMN and identified the enzyme as a membrane-associated, NADPH-dependent cytochrome P-450.

  8. Breath condensate levels of 8-isoprostane and leukotriene B4 after ozone inhalation are greater in sensitive versus nonsensitive subjects.

    Science.gov (United States)

    Alfaro, Mario F; Walby, William F; Adams, William C; Schelegle, Edward S

    2007-01-01

    Ozone (O3) inhalation induces pulmonary function decrements and inflammation. The present study was designed to determine if a relationship exists between O3 induced pulmonary function changes and the presence of inflammatory markers as measured in exhaled breath condensates (EBCs) obtained from O3-sensitive and nonsensitive human subjects. Eight healthy adult volunteers (4 males/4 females, age 18 to 30 years) were studied, characterized as to their ozone sensitivity and placed into 2 groups (sensitive and nonsensitive) with each group having 2 males and 2 females. Subjects completed a 20-minute EBC collection and pulmonary function test (PFT) prior to a single 60-minute bout of cycle ergometer exercise (V(E) = 50-55 L/min) while breathing filtered air (FA) or 0.35 ppm O3. Subjective symptom scores (SSSs) were collected at 6, 20, 40, and 60 minutes during exposure. An immediate postexposure PFT was performed followed by an EBC collection. Subjective symptom scores, EBCs, and PFTs were collected at 1, 4 and 8 hours post exposure. EBCs were analyzed for prostaglandin E2 (PGE2), leukotriene B4 (LTB4), 8-isoprostane, and total nitric oxide (NO) metabolites (nitrate + nitrite content). Sensitive subjects, breathing O3, had significantly greater functional decrements in PFTs, increased SSSs, and increased rapid shallow breathing as well as elevated levels of 8-isoprostane and LTB4 in EBCs compared to those breathing FA. In addition, there were significant increases in nitrate + nitrite content in both sensitive and nonsensitive subjects breathing O3 compared to FA. These results indicate that sensitive subjects have elevated arachidonic acid metabolites in EBCs compared to nonsensitive subjects after O3 inhalation.

  9. COMPARISON OF SELECTIVE AND NON SELECTIVE CYCLO-OXYGENASE 2 INHIBITORS IN EXPERIMENTAL COLITIS EXACERBATION: role of leukotriene B4 and superoxide dismutase

    Directory of Open Access Journals (Sweden)

    José Wander BREGANÓ

    2014-09-01

    Full Text Available Context Nonsteroidal anti-inflammatory drugs are considered one of the most important causes of reactivation of inflammatory bowel disease. With regard to selective cyclo-oxygenase 2 inhibitors, the results are controversial in experimental colitis as well as in human studies. Objectives The aim this study is to compare nonsteroidal anti-inflammatory drugs effects, selective and non selective cyclo-oxygenase 2 inhibitors, in experimental colitis and contribute to the understanding of the mechanisms which nonsteroidal anti-inflammatory drugs provoke colitis exacerbation. Methods Six groups of rats: without colitis, with colitis, and colitis treated with celecoxib, ketoprofen, indometacin or diclofenac. Survival rates, hemoglobin, plasmatic albumin, colonic tissue of interleukin-1ß, interleukin-6, tumor necrosis factor alpha, prostaglandin E2, catalase, superoxide dismutase, thiobarbituric acid-reactive substances, chemiluminescence induced by tert-butil hydroperoxides, and tissue and plasmatic leukotriene B4 were determined. Results The groups treated with diclofenac or indometacin presented lower survival rates, hemoglobin and albumin, higher tissue and plasmatic leukotriene B4 and tissue superoxide dismutase than the group treated with celecoxib. Ketoprofen presented an intermediary behavior between diclofenac/indometacin and celecoxib, concerning to survival rate and albumin. The groups without colitis, with colitis and with colitis treated with celecoxib showed leukotriene B4 and superoxide dismutase lower levels than the groups treated with nonselective cyclo-oxygenase 2 inhibitors. Conclusions Diclofenac and indometacin presented the highest degree of induced colitis exacerbation with nonsteroidal anti-inflammatory drugs, celecoxib did not show colitis exacerbation, and ketoprofen presented an intermediary behavior between diclofenac/indometacin and celecoxib. These results suggest that leukotriene B4 and superoxide dismutase can be

  10. Selectivity of recombinant human leukotriene D(4), leukotriene B(4), and lipoxin A(4) receptors with aspirin-triggered 15-epi-LXA(4) and regulation of vascular and inflammatory responses.

    Science.gov (United States)

    Gronert, K; Martinsson-Niskanen, T; Ravasi, S; Chiang, N; Serhan, C N

    2001-01-01

    Aspirin-triggered lipoxin A(4) (ATL, 15-epi-LXA(4)) and leukotriene D(4) (LTD(4)) possess opposing vascular actions mediated via receptors distinct from the LXA(4) receptor (ALX) that is involved in leukocyte trafficking. Here, we identified these receptors by nucleotide sequencing and demonstrate that LTD(4) receptor (CysLT(1)) is induced in human vascular endothelia by interleukin-1beta. Recombinant CysLT(1) receptor gave stereospecific binding with both [(3)H]-LTD(4) and a novel labeled mimetic of ATL ([(3)H]-ATLa) that was displaced with LTD(4) and ATLa ( approximately IC(50) 0.2 to 0.9 nmol/L), but not with a bioinactive ATL isomer. The clinically used CysLT(1) receptor antagonist, Singulair, showed a lower rank order for competition with [(3)H]-ATLa (IC(50) approximately 8.3 nmol/L). In contrast, LTD(4) was an ineffective competitive ligand for recombinant ALX receptor with [(3)H]-ATLa, and ATLa did not compete for [(3)H]-LTB(4) binding with recombinant LTB(4) receptor. Endogenous murine CysLT(1) receptors also gave specific [(3)H]-ATLa binding that was displaced with essentially equal affinity by LTD(4) or ATLa. Systemic ATLa proved to be a potent inhibitor (>50%) of CysLT(1)-mediated vascular leakage in murine skin (200 microg/kg) in addition to its ability to block polymorphonuclear leukocyte recruitment to dorsal air pouch (4 microg/kg). These results indicate that ATL and LTD(4) bind and compete with equal affinity at CysLT(1), providing a molecular basis for aspirin-triggered LXs serving as a local damper of both vascular CysLT(1) signals as well as ALX receptor-regulated polymorphonuclear leukocyte traffic.

  11. Bone infected/inflamed conditions: Clinical experience with RP517, a Tc99m-leukotriene B4 receptor antagonist

    International Nuclear Information System (INIS)

    Soroa, V.; Nicolini, J.; Camin, L.; Ughetti, R.; Velasquez, M.

    2003-01-01

    Full text: Objectives: Tc 99m- RP517- is a receptor antagonist of Leukotriene B4 (LTB4) labelling predominantly neutrophils, in whole blood. The aim of this clinical trial was to obtain the best acquisition protocol and performance of this agent in detecting bone, joint and soft tissue infected / inflamed pathologies. Methods: RP517 was labelled with 15-20 mCi (555-740MBq) Tc99m per doses. Twenty-six patients studied (F 14, M 12) with range ages 19- 93, suspected of bone, joint and soft tissue infection (25) and one with fever of unknown origin (FUO). Laboratory data, anatomical images and one other scintiscan (MDP, Ga-67 or Tc99m- ciprofloxacin) were evaluated. Acquisition protocol: flow, 30 min, 1, 2, 3, 4 - 24h planar or Spect images as required. Results documented with histology, cultures or clinical follow up. Scans were classified as positive when abnormal uptake persisted in the 24h images or negative when positivity faded, or not detected in later images. Results: Labeling efficiency 86-90%. No adverse reactions encountered. Image protocol modified to a flow, 30 min, 4 and 24h images. Ten-fifteen % of in vivo leucocyte labelling at 1h. Early bile and intestinal excretion did not improve with cleansing enemas or food restrain. Late bone marrow activity is less visible than with in vitro leucocyte labeling. Only 16 patients had proven biopsies and cultures with coincident images in 8 True Positive; other 6 cases were True Negative, 2 False Negative (with positive Ga-67 and Tc99m-ciprofloxacin) and no False Positive. Sensitivity 80%, Specificity 100%. Conclusions: A kit should be produced in order to make it easily available. Pharmaceutically manipulation altering the excretion route could validate studies in abdominal infections and FUO that are now disesteemed. Protocol images must include 24h scans. Advantage of RP517 is the lack of cell labeling manipulation. Larger series must be studied to obtain statistics on joint bone and soft tissue infection

  12. Leukotriene D4 induces chemotaxis in human eosinophilc cell line, EoL-1 cells via CysLT1 receptor activation.

    Science.gov (United States)

    Shirasaki, Hideaki; Kanaizumi, Etsuko; Himi, Tetsuo

    2017-11-01

    Numerous reports have shown that cysteinyl leukotrienes (CysLTs) contribute to tissue accumulation of eosinophils in allergic airway inflammation. To date, only a few studies have reported that CysLTs promote chemotactic activity of human eosinophils in vitro. The purpose of this study was to investigate whether CysLTs promote chemotaxis in the human eosinophilic cell line, EoL-1. EoL-1 cells were induced to differentiate into mature eosinophil-like cells via incubation with butyric acid and cytokines (IL-3, IL-5 and GM-CSF). The chemotactic activity of the differentiated EoL-1 cells was assessed using the commercial cell migration assay kit. LTD 4 elicited dose-related chemotactic activity in the differntiated EoL-1 cells in the range of 1-100 nM. A typical bell-shaped dose-response curve was observed with optimal activity at 10 nM. The chemotactic activity elicited by LTD 4 (10 nM) was significantly inhibited by montelukast (control, 345 ± 19.2 × 10 3 RFU; LTD 4 10 nM alone, 511 ± 39.2 × 10 3 RFU; LTD 4 10 nM plus montelukast 100 nM, 387 ± 28.2 × 10 3 RFU). LTD 4 induces migration in eosinophilic cells via activation of CysLT1 receptor. The present in vitro model may be useful for elucidation of the mechanism underlying CysLT-induced tissue eosinophilia.

  13. Leukotriene-B4 concentrations in exhaled breath condensate and lung function after thirty minutes of breathing technically dried compressed air.

    Science.gov (United States)

    Neubauer, Birger; Struck, Niclas; Mutzbauer, Till S; Schotte, Ulrich; Langfeldt, Norbert; Tetzlaff, Kay

    2002-01-01

    In previous studies it had been shown that leukotriene-B4 [LTB4] concentrations in the exhaled breath mirror the inflammatory activity of the airways if the respiratory tract has been exposed to occupational hazards. In diving the respiratory tract is exposed to cold and dry air and the nasopharynx, as the site of breathing-gas warming and humidification, is bypassed. The aim of the present study was to obtain LTB4-concentrations in the exhaled breath and spirometric data of 17 healthy subjects before and after thirty minutes of technically dried air breathing at normobar ambient pressure. The exhaled breath was collected non-invasively, via a permanently cooled expiration tube. The condensate was measured by a standard enzyme immunoassay for LTB4. Lung function values (FVC, FEV1, MEF 25, MEF 50) were simultaneously obtained by spirometry. The measured pre- and post-exposure LTB4- concentrations as well as the lung function values were in the normal range. The present data gave no evidence for any inflammatory activity in the subjects' airways after thirty minutes breathing technically dried air.

  14. Distinct cellular sources of hepoxilin A3 and leukotriene B4 are used to coordinate bacterial-induced neutrophil transepithelial migration.

    Science.gov (United States)

    Pazos, Michael A; Pirzai, Waheed; Yonker, Lael M; Morisseau, Christophe; Gronert, Karsten; Hurley, Bryan P

    2015-02-01

    Neutrophilic infiltration is a leading contributor to pathology in a number of pulmonary disease states, including cystic fibrosis. Hepoxilin A3 (HXA3) is a chemotactic eicosanoid shown to mediate the transepithelial passage of neutrophils in response to infection in several model systems and at multiple mucosal surfaces. Another well-known eicosanoid mediating general neutrophil chemotaxis is leukotriene B4 (LTB4). We sought to distinguish the roles of each eicosanoid in the context of infection of lung epithelial monolayers by Pseudomonas aeruginosa. Using human and mouse in vitro transwell model systems, we used a combination of biosynthetic inhibitors, receptor antagonists, as well as mutant sources of neutrophils to assess the contribution of each chemoattractant in driving neutrophil transepithelial migration. We found that following chemotaxis to epithelial-derived HXA3 signals, neutrophil-derived LTB4 is required to amplify the magnitude of neutrophil migration. LTB4 signaling is not required for migration to HXA3 signals, but LTB4 generation by migrated neutrophils plays a significant role in augmenting the initial HXA3-mediated migration. We conclude that HXA3 and LTB4 serve independent roles to collectively coordinate an effective neutrophilic transepithelial migratory response. Copyright © 2015 by The American Association of Immunologists, Inc.

  15. Leukotrienes B4, C4, D4 and E4 in the Exhaled Breath Condensate (EBC), Blood and Urine in Patients with Pneumoconiosis

    Czech Academy of Sciences Publication Activity Database

    Pelclová, D.; Fenclová, Z.; Vlčková, Š.; Lebedová, J.; Syslová, K.; Pecha, O.; Běláček, J.; Navrátil, Tomáš; Kuzma, Marek; Kačer, P.

    2012-01-01

    Roč. 50, č. 4 (2012), s. 299-306 ISSN 0019-8366 Institutional support: RVO:61388955 ; RVO:61388971 Keywords : leukotrienes * Lung fibrosis * exhaled breath condensate Subject RIV: CG - Electrochemistry Impact factor: 0.870, year: 2012

  16. Leukotriene B4 induces EMT and vimentin expression in PANC-1 pancreatic cancer cells: Involvement of BLT2 via ERK2 activation.

    Science.gov (United States)

    Kim, You Ri; Park, Mi Kyung; Kang, Gyeong Jin; Kim, Hyun Ji; Kim, Eun Ji; Byun, Hyun Jung; Lee, Moo-Yeol; Lee, Chang Hoon

    2016-12-01

    Leukotriene B 4 (LTB 4 ) is a leukocyte chemoattractant and plays a major role controlling inflammatory responses including pancreatitis. LTB 4 is known to be correlated with cancer progression. LTB 4 induces keratin phosphorylation and reorganization by activating extracellular regulated kinase (ERK) in PANC-1 pancreatic cancer cell lines. However, the role of LTB 4 in epithelial mesenchymal transition (EMT) and vimentin expression in pancreatic cancer cells is unknown. We examined whether LTB 4 induces EMT and vimentin expression by Western blot, si-RNA, and RT-PCR. LTB 4 induced morphological change, decreased E-cadherin expression and increased N-cadherin and vimentin expression. LTB4 increased migration and invasion of PANC-1 cancer cells. LTB 4 dose-dependently upregulated expression of vimentin in PANC-1 cancer cells. LTB 4 -induced vimentin expression was suppressed by LY255283 (BLT2 antagonist). Comp A, a BLT2 agonist, further increased vimentin expression. Gene silencing of BLT2 suppressed LTB 4 -or Comp A-induced vimentin expression in PANC-1 cells. The MEK inhibitor, PD98059 suppressed Comp A-induced vimentin expression. Comp A or transfection of plasmid containing BLT2 cDNA (pC BLT2 ) activated ERK, and BLT2 gene silencing suppressed Comp A-induced ERK activation. ERK2 siRNA abrogated Comp A-induced vimentin expression and ERK2 overexpression enhanced vimentin expression. One of well-known cause of ras mutation, cigarette smoke extracts increased BLT2 expression in PANC-1 cancer cells. Taken together, these results suggest that BLT2 is involved in LTB 4 -induced vimentin expression through ERK2 in PANC-1 cells. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Measurement of tumor necrosis factor-α, leukotriene B4, and interleukin 8 in the exhaled breath condensate in patients with acute exacerbations of chronic obstructive pulmonary disease

    Directory of Open Access Journals (Sweden)

    Fanny WS Ko

    2008-12-01

    Full Text Available Fanny WS Ko1, Ting-Fan Leung2, Gary WK Wong2, Jenny Ngai1, Kin W To1, Susanna Ng1, David SC Hui11Department of Medicine and Therapeutics; 2Department of Pediatrics, The Chinese University of Hong Kong, Hong KongBackground: Assessment of airway inflammation in the clinical course of acute exacerbations of chronic obstructive pulmonary disease (AECOPD may advance our understanding of the pathogenesis and treatment.Objectives: To assess airway inflammation in patients during the course of AECOPD by serial analyses of their exhaled breath condensates (EBC.Methods: Twenty-six patients with AECOPD (22 males, mean[SD] percentage predicted forced expiratory volume in one second (FEV1 44.8 [14.3], 11 with stable COPD, and 14 age and sex-matched healthy controls were studied. Patients with AECOPD were treated with systemic steroid and antibiotic for 7 days. EBC was collected from each patient with AECOPD on Day 5, 14, 30, and 60 post-hospitalization using EcoScreen (VIASYS Healthcare, USA during tidal breathing over 10 minutes. Concentrations of tumor necrosis factor-α (TNF-α, leukotriene B4 (LTB4, and interleukin-8 (IL-8 were measured by enzyme-linked immunosorbent assay.Results: The median (IQR of TNF-α level on Day 5 was 5.08 (3.80–6 .32 pg/ml, which was lower than on Day 14 (5.84 [4.91–9.14] pg/ml, p = 0.017, Day 30 (6.14 [3.82–7.67] pg/ml, p = 0.045, and Day 60 (5.60 [4.53–8.80] pg/ml, p = 0.009. On Day 60, subjects receiving inhaled corticosteroid (ICS had a lower level of TNF-α than those who were not (4.82 [4.06–5.65] vs 7.66 [5.48–10.9] pg/ml, p = 0.02. EBC LTB4 level did not change significantly during recovery from AECOPD whereas IL-8 was mostly undetectable.Conclusions: EBC TNF-α level was low in patients receiving systemic steroid and antibiotic therapy for AECOPD. These findings suggest a potential role for serial EBC TNF-α for noninvasive monitoring of disease activity.Keywords: COPD, exacerbation, exhaled breath

  18. Leucocyte labeling: Preliminary clinical evaluation of RP517, the 99mTc-Leukotriene B4 receptor antagonist for infection/inflammation

    International Nuclear Information System (INIS)

    Soroa, V.E.; Velasquez, M.H.; Nicolini, J.; Ughetti, R.; Camin, L.

    2002-01-01

    99mTc- Leukotriene B4 (LTB4) is a receptor antagonist RP517 that labels predominantly neutrophils, in whole blood. This new radiopharmaceutical has been developed for imaging infection and inflammation. Aim: We conducted this clinical trial to obtain the best protocol imaging and the efficacy of this novel agent in the detection of suspected infected/inflamed patients. Materials and Methods: RP517 was labelled with 15-20 mCi (555-740 MBq) 99mTc for each patient, with a labeling efficiency of 86-95%. Nine patients studied (F 3, M 6) with ages 45-83, suspected of bone, joint and soft tissue infection (8) and one with fever of unknown origin (FUO). Laboratory, anatomical images and one other scintiscan (MDP, Gallium or 99mTc-ciprofloxacin) were used for evaluation. Acquisition protocol: flow, 30 min, 1, 2, 3, 4 - 24h planar or SPECT images if required. Results were compared to histology, cultures, the clinical derivation and follow up. Scans were classified as positive if abnormal uptake persisted through the 24h images or negative when absent pathological uptake or when positivity faded in later images. Results: No adverse reaction encountered. Image protocol modified to a flow, 30 min, 4 and 24h acquisitions. Early bladder excretion and intestinal activity requires previous cleansing enemas and food restrain. Late bone marrow activity is less visible than with in vitro leucocyte labeling. Coincident images were obtained in 3 True Positive, in 5 True Negative except in a hip prosthesis where Gallium and 99mTc-ciprofloxacin showed positivity and RP517 was False negative. Conclusions: A kit should be produced in order to make it available for Nuclear Medicine Departments. Known advantages of RP517 is the lack of in vitro cell labeling manipulation. We do not recommend investigation of FUO or abdominal pathologies. A larger series must be studied in order to be able to obtain statistics on joint bone and soft tissue infection/inflammation where this compound seems to be

  19. Determination of thromboxanes, leukotrienes and lipoxins using high-temperature capillary liquid chromatography-tandem mass spectrometry and on-line sample preparation

    DEFF Research Database (Denmark)

    Dahl, Sandra Rinne; Kleiveland, Charlotte Ramstad; Kassem, Moustapha

    2009-01-01

    An on-line strong cation-exchange (SCX)-reversed-phase (RP) capillary liquid chromatographic (cLC) method with ion-trap tandem mass spectrometric (IT-MS/MS) detection for the simultaneous determination of thromboxane (TX) B(2), TXB(3), leukotriene (LT) B(4), LTD(4) and lipoxin (LX) A(4) in cell...

  20. A new method to evaluate anti-allergic effect of food component by measuring leukotriene B4 from a mouse mast cell line.

    Science.gov (United States)

    Takasugi, Mikako; Muta, Emi; Yamada, Koji; Arai, Hirofumi

    2018-02-01

    Leukotrienes (LTs), chemical mediators produced by mast cells, play an important role in allergic symptoms such as food allergies and hay fever. We tried to construct an evaluation method for the anti-LTB 4 activity of chemical substances using a mast cell line, PB-3c. PB-3c pre-cultured with or without arachidonic acid (AA) was stimulated by calcium ionophore (A23187) for 20 min, and LTB 4 production by the cells was determined by HPLC with UV detection. LTB 4 was not detected when PB-3c was pre-cultured without AA. On the other hand, LTB 4 production by PB-3c pre-cultured with AA was detectable by HPLC, and the optimal conditions of PB-3c for LTB 4 detection were to utilize the cells pre-cultured with 50 µM AA for 48 h. MK-886 (5-lipoxygenase inhibitor) completely inhibited LTB 4 production, but AACOCF 3 (phospholipase A 2 inhibitor) slightly increased LTB 4 production, suggesting that LTB 4 was generated from exogenous free AA through 5-lipoxygenase pathway. We applied this technique to the evaluation of the anti-LTB 4 activity of food components. PB-3c pre-cultured with 50 µM AA for 48 h was stimulated with A23187 in the presence of 50 µM soybean isoflavones (daidzin, genistin, daidzein, and genistein), equol, quercetin, or kaempferol. Genistein, equol, quercetin, and kaempferol strongly inhibited LTB 4 production without cytotoxicity. These results suggest that a new assay system using PB-3c is convenient to evaluate LTB 4 inhibition activity by food components. This method could be utilized for elucidation of the mechanisms of LTB 4 release suppression by food components such as flavonoids and the structure-activity relationship.

  1. Plant Natural Products Calycosin and Gallic Acid Synergistically Attenuate Neutrophil Infiltration and Subsequent Injury in Isoproterenol-Induced Myocardial Infarction: A Possible Role for Leukotriene B4 12-Hydroxydehydrogenase?

    Science.gov (United States)

    Cheng, Yuanyuan; Tse, Hung Fat; Le, X. Chris; Rong, Jianhui

    2015-01-01

    Leukotriene B4 12-hydroxydehydrogenase (LTB4DH) catalyzes the oxidation of proinflammatory LTB4 into less bioactive 12-oxo-LTB4. We recently discovered that LTB4DH was induced by two different natural products in combination. We previously isolated gallic acid from Radix Paeoniae through a bioactivity-guided fractionation procedure. The purpose of this study is to test the hypothesis that LTB4DH inducers may suppress neutrophil-mediated inflammation in myocardial infarction. We first isolated the active compound(s) from another plant, Radix Astragali, by the similar strategy. By evaluating LTB4DH induction, we identified calycosin and formononetin from Radix Astragali by HPLC-ESI-MS technique. We confirmed that gallic acid and commercial calycosin or formononetin could synergistically induce LTB4DH expression in HepG2 cells and human neutrophils. Moreover, calycosin and gallic acid attenuated the effects of LTB4 on the survival and chemotaxis of neutrophil cell culture. We further demonstrated that calycosin and gallic acid synergistically suppressed neutrophil infiltration and protected cardiac integrity in the isoproterenol-induced mice model of myocardial infarction. Calycosin and gallic acid dramatically suppressed isoproterenol-induced increase in myeloperoxidase (MPO) activity and malondialdehyde (MDA) level. Collectively, our results suggest that LTB4DH inducers (i.e., calycosin and gallic acid) may be a novel combined therapy for the treatment of neutrophil-mediated myocardial injury. PMID:26265982

  2. SNAP23-Dependent Surface Translocation of Leukotriene B4 (LTB4) Receptor 1 Is Essential for NOX2-Mediated Exocytotic Degranulation in Human Mast Cells Induced by Trichomonas vaginalis-Secreted LTB4.

    Science.gov (United States)

    Min, Arim; Lee, Young Ah; Kim, Kyeong Ah; El-Benna, Jamel; Shin, Myeong Heon

    2017-01-01

    Trichomonas vaginalis is a sexually transmitted parasite that causes vaginitis in women and itself secretes lipid mediator leukotriene B 4 (LTB 4 ). Mast cells are important effector cells of tissue inflammation during infection with parasites. Membrane-bridging SNARE (soluble N-ethylmaleimide-sensitive factor attachment protein receptor) complexes are critical for fusion during exocytosis. Although T. vaginalis-derived secretory products (TvSP) have been shown to induce exocytosis in mast cells, information regarding the signaling mechanisms between mast cell activation and TvSP is limited. In this study, we found that SNAP23-dependent surface trafficking of LTB 4 receptor 1 (BLT1) is required for nicotinamide adenine dinucleotide phosphate oxidase 2 (NOX2)-mediated exocytotic degranulation of mast cells induced by TvSP. First, stimulation with TvSP induced exocytotic degranulation and reactive oxygen species (ROS) generation in HMC-1 cells. Next, TvSP-induced ROS generation and exocytosis were strongly inhibited by transfection of BLT1 small interfering RNA (siRNA). TvSP induced trafficking of BLT1 from the cytosol to the plasma membrane. We also found that knockdown of SNAP23 abrogated TvSP-induced ROS generation, exocytosis, and surface trafficking of BLT1 in HMC-1 cells. By coimmunoprecipitation, there was a physical interaction between BLT1 and SNAP23 in TvSP-stimulated HMC-1 cells. Taken together, our results suggest that SNAP23-dependent surface trafficking of BLT1 is essential for exocytosis in human mast cells induced by T. vaginalis-secreted LTB 4 Our data collectively demonstrate a novel regulatory mechanism for SNAP23-dependent mast cell activation of T. vaginalis-secreted LTB 4 involving surface trafficking of BLT1. These results can help to explain how the cross talk mechanism between parasite and host can govern deliberately tissue inflammatory responses. Copyright © 2016 American Society for Microbiology.

  3. Oenothera paradoxa defatted seeds extract and its bioactive component penta-O-galloyl-β-D-glucose decreased production of reactive oxygen species and inhibited release of leukotriene B4, interleukin-8, elastase, and myeloperoxidase in human neutrophils.

    Science.gov (United States)

    Kiss, Anna K; Filipek, Agnieszka; Czerwińska, Monika; Naruszewicz, Marek

    2010-09-22

    In this study, we analyzed ex vivo the effect of an aqueous extract of Oenothera paradoxa defatted seeds on the formation of neutrophil-derived oxidants. For defining active compounds, we also tested lypophilic extract constituents such as gallic acid, (+)-catechin, ellagic acid, and penta-O-galloyl-β-D-glucose and a hydrophilic fraction containing polymeric procyanidins. The anti-inflammatory potential of the extract and compounds was tested by determining the release from activated neutrophils of elastase, myeloperoxidase, interleukin-8 (IL-8), and leukotriene B4 (LTB4), which are considered relevant for the pathogenesis of cardiovascular diseases. The extract of O. paradoxa defatted seeds displays potent antioxidant effects against both 4β-phorbol-12β-myristate-α13-acetate- and formyl-met-leu-phenylalanine-induced reactive oxygen species production in neutrophils with IC50 values around 0.2 μg/mL. All types of polyphenolics present in the extract contributed to the extract antioxidant activity. According to their IC50 values, penta-O-galloyl-β-D-glucose was the more potent constituent of the extract. In cell-free assays, we demonstrated that this effect is partially due to the scavenging of O2- and H2O2 oxygen species. The extract and especially penta-O-galloyl-β-D-glucose significantly inhibit elastase, myeloperoxidase IL-8, and LTB4 release with an IC50 for penta-O-galloyl-β-D-glucose of 17±1, 15±1, 6.5±2.5, and around 20 μM, respectively. The inhibition of penta-O-galloyl-β-D-glucose on reactive oxygen species and especially on O2- production, myeloperoxidase, and chemoattractant release may reduce the interaction of polymorphonuclear leukocyte with the vascular endothelium and by that potentially diminish the risk of progression of atherosclerosis development.

  4. Bloqueio do receptor de leucotrieno CysLT1 em pacientes com fenômeno de Raynaud: evidência capilaroscópica do papel do leucotrieno CysLT1 receptor inhibition in patients with Raynaud's phenomenon: capillaroscopic evidence of the role of leukotriene

    Directory of Open Access Journals (Sweden)

    Mario Newton Leitão de Azevedo

    2012-02-01

    Full Text Available OBJETIVO: Avaliar a ação do medicamento inibidor do receptor de leucotrieno CysLT1 (montelucaste nas alterações vasculares das mãos em pacientes com fenômeno de Raynaud. MÉTODOS: Foram selecionadas pacientes com fenômeno de Raynaud secundário à doença inflamatória do tecido conjuntivo, excluindo tabagismo, hipertensão arterial e diabetes mellitus. As pacientes mantiveram a medicação prévia e iniciaram o uso de montelucaste 10 mg/dia por 60 dias. Foi realizada capilaroscopia periungueal dos dedos das mãos antes do uso da medicação e após 30 e 60 dias. A análise estatística foi feita por meio de porcentagem, média, desvio-padrão e teste exato de Fisher, com intervalo de confiança de 95%. RESULTADOS: Foram estudadas cinco pacientes mulheres, brancas, com fenômeno de Raynaud secundário a doenças do tecido conjuntivo, das quais três apresentavam esclerodermia e duas apresentavam doença mista do tecido conjuntivo. A média de idade foi de 42,4 ± 12,4 anos, e a média de tempo de doença foi de 9,6 ± 4,8 anos. As pacientes estavam em uso de até 20 mg/dia de prednisona (pacientes com doença mista do tecido conjuntivo, nifedipina, pentoxifilina. As medicações foram mantidas. Após o uso de inibidor de receptor de leucotrieno por dois meses, o controle com capilaroscopia ungueal demonstrou diminuição do edema e da palidez e normalização do número, tamanho e distribuição dos capilares. CONCLUSÃO: O uso do montelucaste modificou as alterações capilares observadas na capilaroscopia periungueal de pacientes com fenômeno de RaynaudOBJECTIVE: To assess the effect of the leukotriene receptor inhibitor (montelukast on vascular alterations in fingers of patients with Raynaud's phenomenon. METHODS: Patients with Raynaud's phenomenon of the hands secondary to inflammatory connective tissue disease were selected, and those with the following characteristics were excluded: smokers, arterial hypertension, and diabetes

  5. Ligand-induced tyrosine phosphorylation of cysteinyl leukotriene receptor 1 triggers internalization and signaling in intestinal epithelial cells

    DEFF Research Database (Denmark)

    Parhamifar, Ladan; Sime, Wondossen; Yudina, Yuliana

    2010-01-01

    Leukotriene D(4) (LTD(4)) belongs to the bioactive lipid group known as eicosanoids and has implications in pathological processes such as inflammation and cancer. Leukotriene D(4) exerts its effects mainly through two different G-protein-coupled receptors, CysLT(1) and CysLT(2). The high affinit...

  6. Endogenous leukotriene formation during anaphylactic shock

    International Nuclear Information System (INIS)

    Keppler, A.; Oerning, L.; Bernstroem, K.; Hammarstroem, S.

    1987-01-01

    Leukotriene (LT)C 4 is a biologically active substance, presumed to play major roles as a mediator of allergic and anaphylactic reactions. It is formed e.g. by basophilic and eosinophilic leukocytes, monocytes, macrophages, and mast cells. In cells having IgE receptors, bridging of these by divalent anti-IgE-receptor antibodies or by interaction between receptor-bound IgE and anti-IgE will induce LTC 4 formation. Leukotriene formation has also been demonstrated in other in vitro models of immediate hypersensivity. The biological actions of LTC 4 , comprise induction of airway obstruction, constriction of coronary arteries, hypotension, and plasma extravasation. Leukotriene formation in vivo may mediate anaphylactic shock symptoms and cause the death of an animal. In order to prove the presumed mediator role of this substance in anaphylactic reactions, it is necessary to demonstrate its endogenous formation during shock. Studies on the metabolism of LTC 4 have revealed rapid catabolism by various transformations of the peptide substituent. Recently, three metabolites were demonstrated to be excreted as end-products in man (LTE 4 ,) and the rat (N-acetyl LTE 4 and N-acetyl 11-trans LTE 4 ). By monitoring biliary N-acetyl LTE 4 levels, endogenous leukotriene formation in the rat was demonstrated in vivo after tissue trauma and endotoxin shock. We now wish to report evidence for endogenous leukotriene C 4 production during anaphylactic shock in guinea pigs. 37 refs. (author)

  7. Upregulation of Leukotriene Receptors in Gastric Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Venerito, Marino [Department of Gastroenterology, Hepatology and Infectious Diseases, Otto-von-Guericke University, Leipziger Str. 44, Magdeburg 39120 (Germany); Kuester, Doerthe [Institute of Pathology, Otto-von-Guericke University, Leipziger Str. 44, Magdeburg 39120 (Germany); Harms, Caroline [Department of Gastroenterology, Hepatology and Infectious Diseases, Otto-von-Guericke University, Leipziger Str. 44, Magdeburg 39120 (Germany); Schubert, Daniel [Department of General, Visceral and Vascular Surgery, Otto-von-Guericke University Magdeburg, Leipziger Str. 44, Magdeburg 39120 (Germany); Wex, Thomas, E-mail: thomas.wex@med.ovgu.de; Malfertheiner, Peter [Department of Gastroenterology, Hepatology and Infectious Diseases, Otto-von-Guericke University, Leipziger Str. 44, Magdeburg 39120 (Germany)

    2011-08-08

    Leukotrienes (LT) mediate allergic and inflammatory processes. Previously, we identified significant changes in the expression pattern of LT receptors in the gastric mucosa after eradication of Helicobacter pylori infection. The aim of the present study was to evaluate the expression of 5-lipoxygenase (5-LOX) and LT receptors in gastric cancer (GC). The expression of 5-LOX and receptors for LTB4 (BLT-1, BLT-2) and cysteinyl-LT (CysLT-1, CysLT-2) were analyzed by immunohistochemistry (IHC) in GC samples of 35 consecutive patients who underwent gastrectomy and in 29 tumor-free tissue specimens from gastric mucosa. Male-to-female ratio was 24:11. The median age was 70 years (range 34–91). Twenty-two patients had GC of intestinal, six of diffuse, six of mixed and one of undifferentiated type. The IHC analysis showed a nearly ubiquitous expression of studied proteins in GC (88–97%) and in tumor-free specimens as well (89–100%). An increase in the immunoreactive score of both BLT receptors and CysLT-1 was observed in GC compared to tumor-free gastric mucosa (p < 0.001 for BLT-1; p < 0.01 for BLT-2 and CysLT-1, Mann-Whitney U-test). No differences in the IHC expression of 5-LOX and CsyLT-2 were observed between GC and tumor-free mucosa. The expression of BLT-2, CysLT-1 and CysLT-2 was increased in GC of intestinal type when compared to the diffuse type (p < 0.05; Mann-Whitney U-test). LTB4 receptors and CysLT-1 are up-regulated in GC tissue implying a role in gastric carcinogenesis.

  8. Cysteinyl leukotriene signaling aggravates myocardial hypoxia in experimental atherosclerotic heart disease

    DEFF Research Database (Denmark)

    Nobili, Elena; Salvado, M Dolores; Folkersen, Lasse Westergaard

    2012-01-01

    Cysteinyl-leukotrienes (cys-LT) are powerful spasmogenic and immune modulating lipid mediators involved in inflammatory diseases, in particular asthma. Here, we investigated whether cys-LT signaling, in the context of atherosclerotic heart disease, compromises the myocardial microcirculation and ...

  9. Leukotriene B4 receptors on guinea pig alveolar eosinophils

    International Nuclear Information System (INIS)

    Maghni, K.; de Brum-Fernandes, A.J.; Foeldes-Filep, E.G.; Gaudry, M.; Borgeat, P.; Sirois, P.

    1991-01-01

    The existence of receptors for LTB4 on highly purified guinea pig alveolar eosinophils was investigated. Massive infiltration of eosinophils in alveolar spaces was induced in guinea pigs by i.v. injections of Sephadex beads G50 (16 mg/kg). Alveolar eosinophils (50 x 10(6) cells) were purified to approximately 98% by Percoll continuous density gradient centrifugation. The binding studies indicated that alveolar eosinophils bind LTB4 in a saturable, reversible and specific manner. Scatchard analysis indicated the existence of high-affinity binding sites (Kd1 = 1.00 ± 0.22 nM; Bmax1 = 966 ± 266 sites/cell) and low-affinity binding sites (Kd2 = 62.5 ± 8.9 nM; Bmax2 = 5557 ± 757 sites/cell). The metabolism of LTB4 by alveolar eosinophils in binding conditions was assessed by RP-HPLC and no significant degradation of [3H]LTB4 was observed. LTB4 dose-dependently stimulated eosinophil migration in both chemokinesis and chemotaxis assays with an EC50 value of 1.30 ± 0.14 and 18.14 ± 1.57 nM, respectively. LTB4 caused a dose-dependent increase in the production of superoxide anion with an apparent EC50 value of 50 x 10(-9) M in the authors experimental conditions. LTB4 also induced a dose-dependent increase in the generation of TxA2 with an EC50 value of 46.2 x 10(-9) M. Taken together, their results demonstrated that guinea pig alveolar eosinophils express two classes of specific receptors for LTB4. The high-affinity binding sites seem associated to chemokinesis and chemotaxis whereas the low-affinity binding sites seem associated to superoxide anion production and generation of TxA2. The existence of LTB4 receptors in eosinophils could explain the presence of these cells in hypersensitivity reactions

  10. Development of a model system to study leukotriene-induced modification of radiation sensitivity in mammalian cells

    Energy Technology Data Exchange (ETDEWEB)

    Walden, Jr, T L; Holahan, Jr, E V; Catravas, G N

    1986-01-01

    Leukotrienes (LT) are an important class of biological mediators for which no information exists concerning their synthesis following a radiation insult or on their ability to modify cellular response to a subsequent radiation exposure. Results are presented which illustrate that the Chinese hamster lung fibroblast cell line, V79A03, is useful as a model system to study the metabolic fate of leukotrienes and the effect of LT on radiation sensitivity of mammalian cells in vitro. (U.K.).

  11. Leukotriene formation by purified 5-lipoxygenase from rat basophilic leukemia cells

    International Nuclear Information System (INIS)

    Hogaboom, G.K.; Cook, M.; Sarau, H.M.; Newton, J.F.; Crooke, S.T.

    1986-01-01

    Arachidonate 5-lipoxygenase (5-LO) from rat basophilic leukemia (RBL-1) cell high speed (105,000 x g for 60 min) supernatants was purified to electrophoretic homogeneity by gel filtration and anion-exchange protein-high pressure liquid chromatography (HPLC). The 5-LO rapidly converted [ 14 C]arachidonate at 20 0 C to [ 14 C]5-hydroperoxyeicosate-traenoic acid (HPETE) as determined by reversed phase-HPLC, scanning spectrophotometry and radiochemical detection. In addition, 5-LO converted both 5-HPETE and arachidonate to 5,12-dihydroxyeicosatetraenoic acids (diHETEs). The 5,12-diHETEs were identified as 6-trans-leukotriene (LT) B4 and 6-trans-12-epi-LTB4 as determined by reversed phase HPLC, scanning spectrophotometry and gas chromatography-mass spectrometry. These data indicate that the RBL-1 5-LO and LTA4 synthetase activities reside on the same protein and that it catalyzes the bioconversion of arachidonate to not only 5-HPETE but also to LTA4. The results suggest that a critical regulatory step in LT biosynthesis in mammalian systems involves the intricate coupling of the enzymes 5-LO and LTA4 synthetase and the interactions of their respective cofactors, substrates and reaction products

  12. The cysteinyl leukotriene 2 receptor contributes to all-trans retinoic acid-induced differentiation of colon cancer cells

    International Nuclear Information System (INIS)

    Bengtsson, Astrid M; Jönsson, Gunilla; Magnusson, Cecilia; Salim, Tavga; Axelsson, Cecilia; Sjölander, Anita

    2013-01-01

    Cysteinyl leukotrienes (CysLTs) are potent pro-inflammatory mediators that are increased in samples from patients with inflammatory bowel diseases (IBDs). Individuals with IBDs have enhanced susceptibility to colon carcinogenesis. In colorectal cancer, the balance between the pro-mitogenic cysteinyl leukotriene 1 receptor (CysLT 1 R) and the differentiation-promoting cysteinyl leukotriene 2 receptor (CysLT 2 R) is lost. Further, our previous data indicate that patients with high CysLT 1 R and low CysLT 2 R expression have a poor prognosis. In this study, we examined whether the balance between CysLT 1 R and CysLT 2 R could be restored by treatment with the cancer chemopreventive agent all-trans retinoic acid (ATRA). To determine the effect of ATRA on CysLT 2 R promoter activation, mRNA level, and protein level, we performed luciferase gene reporter assays, real-time polymerase chain reactions, and Western blots in colon cancer cell lines under various conditions. ATRA treatment induces CysLT 2 R mRNA and protein expression without affecting CysLT 1 R levels. Experiments using siRNA and mutant cell lines indicate that the up-regulation is retinoic acid receptor (RAR) dependent. Interestingly, ATRA also up-regulates mRNA expression of leukotriene C 4 synthase, the enzyme responsible for the production of the ligand for CysLT 2 R. Importantly, ATRA-induced differentiation of colorectal cancer cells as shown by increased expression of MUC-2 and production of alkaline phosphatase, both of which could be reduced by a CysLT 2 R-specific inhibitor. This study identifies a novel mechanism of action for ATRA in colorectal cancer cell differentiation and demonstrates that retinoids can have anti-tumorigenic effects through their action on the cysteinyl leukotriene pathway

  13. Impact of arachidonic versus eicosapentaenoic acid on exotonin-induced lung vascular leakage: relation to 4-series versus 5-series leukotriene generation.

    Science.gov (United States)

    Grimminger, F; Wahn, H; Mayer, K; Kiss, L; Walmrath, D; Seeger, W

    1997-02-01

    Escherichia coli hemolysin (HlyA) is a proteinaceous pore-forming exotoxin that is implicated as a significant pathogenicity factor in extraintestinal E. coli infections including sepsis. In perfused rabbit lungs, subcytolytic concentrations of the toxin evoke thromboxane-mediated vasoconstriction and prostanoid-independent protracted vascular permeability increase (11). In the present study, the influence of submicromolar concentrations of free arachidonic acid (AA) and eicosapentaenoic acid (EPA) on the HlyA-induced leakage response was investigated. HlyA at concentration from 0.02 to 0.06 hemolytic units/ml provoked a dose-dependent, severalfold increase in the capillary filtration coefficient (Kfc), accompanied by the release of leukotriene(LT)B4, LTC4, and LTE4 into the recirculating buffer fluid. Simultaneous application of 100 nmol/L AA markedly augmented the HlyA-elicited leakage response, concomitant with an amplification of LTB4 release and a change in the kinetics of cysteinyl-LT generation. In contrast, 50 to 200 nmol/L EPA suppressed in a dose-dependent manner the HlyA-induced increase in Kfc values. This was accompanied by a blockage of 4-series LT generation and a dose-dependent appearance of LTB5, LTC5, and LTE5. In addition, EPA fully antagonized the AA-induced amplification of the HlyA-provoked Kfc increase, again accompanied by a shift from 4-series to 5-series LT generation. We conclude that the vascular leakage provoked by HlyA in rabbit lungs is differentially influenced by free AA versus free EPA, related to the generation of 4- versus 5-series leukotrienes. The composition of lipid emulsions used for parenteral nutrition may thus influence inflammatory capillary leakage.

  14. Elevated Plasma Level of Leukotrienes in Bronchial Asthma Patients: A Possible Clinical Relevance

    Directory of Open Access Journals (Sweden)

    Mahmoud Mansour

    1994-01-01

    Full Text Available Plasma from bronchial asthma patients and healthy controls was investigated for the content of lipoxygenase products. After lipid extraction using SEP-PAK C18 Cartridges, the lipoxygenase products were measured by Enzyme-Immunoassay. Elevated chemotactic B4 was found in plasma from asthmatic patients with mean value (483±75 pmoUL, while the mean value in normal healthy donors was (140± 12.1 pmol/L (M±SE. The levels of spasmogenic cysteinyl containing leukotrienes were also very high in the bronchial asthma patients. Elevations of leukotriene B4 and cysteinyl containing leukotrienes were detected during attacks of bronchial asthma. These results suggest that leukotriene B4 may be important in the pathogenesis of bronchial asthma and confirmed that peptidoleukotrienes playa role as chemical mediators during the asthmatic attack.

  15. Leukotrienes and leukotriene modifiers in pediatric allergic diseases

    African Journals Online (AJOL)

    Ehab

    ... 12(1):3-12. 3. Leukotrienes and leukotriene modifiers in pediatric allergic diseases ... childhood allergic diseases. This review ... produce cysteinyl-LTs and LTB4 spontaneously in vitro.8. Although nonleukocyte cells generally do not have sufficient 5-LO and FLAP to synthesize .... uninterrupted sleep in these patients.55.

  16. [Leukotriene antagonists: a new approach in the treatment of asthma].

    Science.gov (United States)

    Devillier, P; Bessard, G; Advenier, C

    1997-06-01

    Inflammation plays an essential role in the genesis of airflow obstruction and bronchial hyper-reactivity in the early stages of clinical asthma. The treatment of bronchial inflammation has become an essential element in the therapeutic strategy and principally rests on inhaled glucocorticoids. Amongst a number of inflammatory mediators leukotrienes occupy a privileged place by the power of their inflammatory and constrictor effects on bronchial smooth muscles. These properties have justified the clinical development of inhibitors of their synthesis and of specific antagonists to their receptors. Leukotriene antagonists are specific for a sub type of leukotriene receptors C4, D4 and E4 which is implicated in the majority of the bronchial constrictor and inflammatory effects of leukotrienes. The antagonists of Cys-LT1 receptor but also the inhibitors of the leukotriene synthesis exert an additive bronchodilator effect to those of B2 stimulants confirming an efficacious protection vis a vis bronchial provocation tests and above all they improve the clinical scores, lung function and also enable a decrease in the consumption of beta 2 agonists. The marketing of these products represents a major event because it corresponds to the advent of a new therapeutic class. The ease of administration by the oral route, their demonstrated efficacy and their good tolerance profile (in particular for ICI 204.219, and antagonists to Cys-LT1 receptors) are elements which foresee a success for this new asthmatic treatment. However numerous studies, notably comparative studies vis a vis reference treatments will be necessary to define their place in the strategic approach to the treatment of asthma.

  17. Leukotriene E4 induces airflow obstruction and mast cell activation through the cysteinyl leukotriene type 1 receptor.

    Science.gov (United States)

    Lazarinis, Nikolaos; Bood, Johan; Gomez, Cristina; Kolmert, Johan; Lantz, Ann-Sofie; Gyllfors, Pär; Davis, Andy; Wheelock, Craig E; Dahlén, Sven-Erik; Dahlén, Barbro

    2018-03-05

    Leukotriene (LT) E 4 is the final active metabolite among the cysteinyl leukotrienes (CysLTs). Animal studies have identified a distinct LTE 4 receptor, suggesting that current cysteinyl leukotriene type 1 (CysLT 1 ) receptor antagonists can provide incomplete inhibition of CysLT responses. We tested this hypothesis by assessing the influence of the CysLT 1 antagonist montelukast on responses induced by means of inhalation of LTE 4 in asthmatic patients. Fourteen patients with mild intermittent asthma and 2 patients with aspirin-exacerbated respiratory disease received 20 mg of montelukast twice daily and placebo for 5 to 7 days in a randomized, double-blind, crossover study (NCT01841164). The PD 20 value was determined at the end of each treatment period based on an increasing dose challenge. Measurements included lipid mediators in urine and sputum cells 4 hours after LTE 4 challenge. Montelukast completely blocked LTE 4 -induced bronchoconstriction. Despite tolerating an at least 10 times higher dose of LTE 4 after montelukast, there was no difference in the percentage of eosinophils in sputum. Urinary excretion of all major lipid mediators increased after LTE 4 inhalation. Montelukast blocked release of the mast cell product prostaglandin (PG) D 2 , as well as release of PGF 2α and thromboxane (Tx) A 2 , but not increased excretion of PGE 2 and its metabolites or isoprostanes. LTE 4 induces airflow obstruction and mast cell activation through the CysLT 1 receptor. Copyright © 2018 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  18. Role of leukotrienes in asthma pathophysiology

    DEFF Research Database (Denmark)

    Bisgaard, H

    2000-01-01

    Inflammation is an essential component of asthma pathophysiology. While beta(2)-agonists are often used for short-term relief of acute bronchospasm, anti-inflammatory agents are required for the long-term management of chronic inflammation in this disease. Corticosteroids have emerged as the first......-line anti-inflammatory therapy for asthma management. However, in some patients, especially children, the high doses of corticosteroids that may be required to control features of hyperresponsiveness, including exercise-induced asthma, raise safety concerns. Thus, there is a need for complementary anti......-inflammatory, steroid-sparing agents in asthma therapy. Several inflammatory mediators have been targeted in an attempt to thwart this inflammatory process, but so far with little success. The cysteinyl leukotrienes (CysLT), LTC(4), LTD(4), and LTE(4), have been shown to be essential mediators in asthma, making them...

  19. Low expression of CysLT1R and high expression of CysLT2R mediate good prognosis in colorectal cancer

    DEFF Research Database (Denmark)

    Magnusson, Cecilia; Mezhybovska, Maryna; Lörinc, Ester

    2010-01-01

    Colorectal cancer is the third most common cancer type in the Western world. In search of new treatment possibilities, the inflammation mediators, know as cysteinyl leukotrienes (CysLTs), have been shown to regulate intestinal epithelial cell survival and proliferation via the CysLT(1)R, and cell...... microarray of 329 colorectal patients. We found that high nuclear expression of CysLT(1)R is associated with a poor prognosis, whereas high nuclear expression of CysLT(2)R is associated with a good prognosis. We also observed that patients with colorectal tumours characterised by high CysLT(1)R but low Cys...

  20. Cysteinyl-Leukotriene Receptors and Cellular Signals

    Directory of Open Access Journals (Sweden)

    G. Enrico Rovati

    2007-01-01

    Full Text Available Cysteinyl-leukotrienes (cysteinyl-LTs exert a range of proinflammatory effects, such as constriction of airways and vascular smooth muscle, increase of endothelial cell permeability leading to plasma exudation and edema, and enhanced mucus secretion. They have proved to be important mediators in asthma, allergic rhinitis, and other inflammatory conditions, including cardiovascular diseases, cancer, atopic dermatitis, and urticaria. The classification into subtypes of the cysteinyl-LT receptors (CysLTRs was based initially on binding and functional data, obtained using the natural agonists and a wide range of antagonists. CysLTRs have proved remarkably resistant to cloning. However, in 1999 and 2000, the CysLT1R and CysLT2R were successfully cloned and both shown to be members of the G-protein coupled receptors (GPCRs superfamily. Molecular cloning has confirmed most of the previous pharmacological characterization and identified distinct expression patterns only partially overlapping. Recombinant CysLTRs couple to the Gq/11 pathway that modulates inositol phospholipids hydrolysis and calcium mobilization, whereas in native systems, they often activate a pertussis toxin-insensitive Gi/o-protein, or are coupled promiscuously to both G-proteins. Interestingly, recent data provide evidence for the existence of an additional receptor subtype that seems to respond to both cysteinyl-LTs and uracil nucleosides, and of an intracellular pool of CysLTRs that may have roles different from those of plasma membrane receptors. Finally, a cross-talk between the cysteinyl-LT and the purine systems is being delineated. This review will summarize recent data derived from studies on the molecular and cellular pharmacology of CysLTRs.

  1. SRS-A leukotrienes decrease the activity of human respiratory cilia

    DEFF Research Database (Denmark)

    Bisgaard, H; Pedersen, M

    1987-01-01

    We have studied the effects of the slow reacting substance of anaphylaxis (SRS-A) constituents leukotrienes (LT) C4 and D4 on the ciliary activity of human respiratory cells. The ciliary beat frequency on human nasal cells harvested by cell scraping from the inferior turbinate was measured...

  2. Identification of a murine cysteinyl leukotriene receptor by expression in Xenopus laevis oocytes

    DEFF Research Database (Denmark)

    Mollerup, Jens; Jørgensen, Sune T.; Hougaard, Charlotte

    2001-01-01

    We report the identification of an EST encoding a murine cysteinyl leukotriene (mCysLT) receptor. LTD4, LTC4 and LTE4 but not LTB4 or various nucleotides activated Ca2+-evoked Cl- currents in mCysLT1 expressing Xenopus laevis oocytes. The response to LTD4 was blocked by MK-571, reduced by pretrea...... by pretreatment with pertussis toxin (PTX), and was partly dependent on extracellular Ca2+. The identified murine CysLT1 receptor differs from the hCysLT1 receptor with regard to PTX sensitivity, receptor-mediated Ca2+ influx, and antagonist sensitivity....

  3. Expression of cysLT1 and cysLT2 Receptor in Chronic Hyperplastic Eosinophilic Sinusitis

    International Nuclear Information System (INIS)

    Ouyang, Yuhui; Kamijo, Atsushi; Murata, Shin-ichi; Okamoto, Atsushi; Endo, Shuichiro; Katoh, Ryohei; Masuyama, Keisuke

    2009-01-01

    Elevated production of cysteinyl leukotrienes (cysLTs) from sinus tissues and abundant sinus eosinophils are characteristic features of chronic hyperplastic eosinophilic sinusitis (CHS). CysLTs exert their action through G-protein-coupled receptors named cysLTs receptor type I (cysLT1R) and type II (cysLT2R). These expressions of cysLT receptors in the sinus mucosa have yet to be clarified and the relationship between eosinophilia and the expression of these receptors remains obscure. We compared the expressions of cysLT1R and cysLT2R in the sinus mucosa in patients with CHS, non-eosinophilic chronic sinusitis (NECS), and control sinus tissues; and analyzed the correlation between the expression of CysLTRs and the presence of sinus eosinophils by immunohistochemistry and real-time PCR. A significantly higher percentage of eosinophils expressing cysLT2R protein was observed in patients with CHS compared with NECS and controls. In addition, cysLT2R mRNA expression in CHS was significantly higher than in NECS and controls. Furthermore, a positive correlation was observed between cysLT2R mRNA expression and the number of infiltrated eosinophils. In contrast, the cysLT1R mRNA expression did not differ significantly among these groups. The effect of cysLTs on sinus eosinophils may be mediated through the cysLT2R in patients with CHS. These results may suggest the therapeutic benefit of cysLT2R antagonists in CHS

  4. Leukotriene B4 catabolism: quantitation of leukotriene B4 and its omega-oxidation products by reversed-phase high-performance liquid chromatography.

    Science.gov (United States)

    Shak, S

    1987-01-01

    LTB4 and its omega-oxidation products may be rapidly, sensitively, and specifically quantitated by the methods of solid-phase extraction and reversed-phase high-performance liquid chromatography (HPLC), which are described in this chapter. Although other techniques, such as radioimmunoassay or gas chromatography-mass spectrometry, may be utilized for quantitative analysis of the lipoxygenase products of arachidonic acid, only the technique of reversed-phase HPLC can quantitate as many as 10 metabolites in a single analysis, without prior derivatization. In this chapter, we also reviewed the chromatographic theory which we utilized in order to optimize reversed-phase HPLC analysis of LTB4 and its omega-oxidation products. With this information and a gradient HPLC system, it is possible for any investigator to develop a powerful assay for the potent inflammatory mediator, LTB4, or for any other lipoxygenase product of arachidonic acid.

  5. The effect of n-3 fatty acids and coenzyme Q10 supplementation on neutrophil leukotrienes, mediators of inflammation resolution and myeloperoxidase in chronic kidney disease.

    Science.gov (United States)

    Barden, Anne E; Shinde, Sujata; Burke, Valerie; Puddey, Ian B; Beilin, Lawrence J; Irish, Ashley B; Watts, Gerald F; Mori, Trevor A

    2018-03-22

    Neutrophils release leukotriene (LT)B 4 and myeloperoxidase (MPO) that may be important mediators of chronic inflammation in chronic kidney disease (CKD). The n-3 fatty acids (n-3 FA) eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) have the potential to attenuate inflammation through production of LTB 5 and the Specialized Proresolving Lipid Mediators (SPM) that promote the resolution of inflammation. In animal models, coenzyme Q10 (CoQ) also attenuates inflammation by reducing MPO and LTB 4 . This study evaluated the independent and combined effects of n-3 FA and CoQ supplementation on neutrophil leukotrienes, the pro-inflammatory eicosanoid 5-hydroxyeicosatetraenoic acid (5-HETE), SPM, and plasma MPO, in patients with CKD. In a double-blind, placebo-controlled intervention of factorial design, 85 patients with CKD were randomized to either n-3 FA (4 g), CoQ (200 mg), both supplements, or control (4 g olive oil), daily for 8 weeks. Plasma MPO and calcium ionophore-stimulated neutrophil release of LTs, 5-HETE and SPM were measured at baseline and after 8 weeks. Seventy four patients completed the intervention. n-3 FA, but not CoQ, significantly increased neutrophil LTB 5 (P n-3 FA or CoQ. Plasma MPO was significantly reduced with n-3 FA alone (P = 0.013) but not when given in combination with CoQ. n-3 FA supplementation in patients with CKD leads to increased neutrophil release of LTB 5 and several SPM, as well as a reduction in plasma MPO that may have important implications for limiting chronic inflammation. Copyright © 2018 Elsevier Inc. All rights reserved.

  6. Concentrations of cysteinyl leukotrienes in urine and bronchoalveolar lavage fluid of cats with experimentally induced asthma.

    Science.gov (United States)

    Norris, Carol R; Decile, Kendra C; Berghaus, Londa J; Berghaus, Roy D; Walby, William F; Schelegle, Edward S; Hyde, Dallas M; Gershwin, Laurel J

    2003-11-01

    To evaluate changes in cysteinyl leukotriene (LT) concentrations in urine and bronchoalveolar lavage fluid (BALF) in cats with experimentally induced asthma. 19 cats with experimentally induced asthma and 5 control cats. Cats were sensitized to Bermuda grass or house dust mite allergen, and phenotypic features of asthma were confirmed with intradermal skin testing, evaluation of BALF eosinophil percentages, and pulmonary function testing. A competitive ELISA kit for LTC4, LTD4, and LTE4 was used for quantitative analysis of LTs. Urinary creatinine concentrations and BALF total protein (TP) concentrations were measured, and urinary LT-to-creatinine ratios and BALF LT-to-TP ratios were calculated. Mean urinary LT-to-creatinine ratios did not differ significantly between control cats and allergen-sensitized cats before or after sensitization and challenge exposure with saline (0.9% NaCl) solution or allergen, respectively. In BALF the mean LT-to-TP ratio of control cats did not differ significantly before or after sensitization and challenge exposure with saline. Asthmatic cats had BALF LT-to-TP ratios that were significantly lower than control cats at all time points, whereas ratios for asthmatic cats did not differ significantly among the various time points. Although LTs were readily detectable in urine, no significant increases in urinary LT concentrations were detected after challenge in allergen-sensitized cats. Spot testing of urinary LT concentrations appears to have no clinical benefit for use in monitoring the inflammatory asthmatic state in cats. The possibility that cysteinyl LTs bind effectively to their target receptors in BALF and, thus, decrease free LT concentrations deserves further study.

  7. Stereoselective semi-hydrogenation and deuteration of a diacetylenic precursor of leukotriene B sub 4 methyl ester

    Energy Technology Data Exchange (ETDEWEB)

    Pontikis, R.; Le Merrer, Y.; Depezay, J.-C. (U.D.C. CNRS-INSERM (URA 400), 75, Paris (France). Lab. de Chimie et Biochimie Pharamacologiques et Toxicologiques); Petillot, Y.; Rousseau, B.; Beaucourt, J.P. (CEA Centre d' Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette (France). Service des Molecules Marquees)

    1990-10-01

    (6,7,14,15-{sup 2}H4)-Leukotriene B4 methyl ester was prepared by reduction with deuterium gas of a suitable precursor (deuterium incorporation > 90%). Several catalytic semi-hydrogenations were affected in order to determine the best conditions for the labeling step. (author).

  8. Development of 125I-leukotriene B4 radio-immunoassay and its clinical applications

    International Nuclear Information System (INIS)

    Wang Zhaoyue; He Yang; Chen Dechun; Ruan Changgeng

    1992-11-01

    LTB 4 was extracted from porcine blood with the help of HPLC. The antiserum was raised by immunizing rabbits with LTB 4 which has been conjugated with bovine serum albumin by mixed anhydride method method. The titer of the anti-body was 1:7000 and the affinity coefficient was 2.1 x 10 9 L/M. Its cross reactions with LTA 4 , LTC 4 , LTD 4 and other arachidonic acid metabolites were 0.4 ∼ 6.4%.The 125 I-histamine-LTB 4 was prepared by using chloramine T procedure. The minimum detectable limit was 25 pg/tube. The recovery rate was 84.2 ∼ 113%. The intra- and inter-assay coefficient of variation were 5.2% and 9.7% respectively. The amount of LTB 4 produced by normal human PMNL which were stimulated by ionophore A23187 and arachidonic acid was 695.5 ± 329.7 pg/10 6 cells. PMNL of patients with various acute leukemias and CML generated an increased quantities of LTB 4 , TXB 2 and 6-keto-PGF 1α . LTB 4 produced by PMNL also showed an increasing tendency in both cerebral thrombosis and acute myocardial infarction, but was not altered in cerebral hemorrhage of non-infarction coronary disease

  9. A specific assay for leukotriene B4 in human whole blood

    DEFF Research Database (Denmark)

    Fogh, J; Poulsen, L K; Bisgaard, H

    1992-01-01

    between standard and sample dilution curves. Purification was, therefore, extended by combinations of the following steps: 1) protein precipitation, 2) lipid extractions, and 3) high-performance liquid chromatography (HPLC). One of two commercially available LTB4 standards was found to contain multiple...... components, several of which were immunoreactive in RIA. Even for the standard containing pure LTB4, interference was demonstrated by lack of parallelism between sample and standard dilution curves. Testing eight combinations of varying purification steps, we found that only a three-step purification...

  10. Cysteinyl leukotrienes in the urine of patients with liver diseases.

    Science.gov (United States)

    Uemura, M; Buchholz, U; Kojima, H; Keppler, A; Hafkemeyer, P; Fukui, H; Tsujii, T; Keppler, D

    1994-10-01

    The significance of cysteinyl leukotrienes was investigated in patients with liver diseases by measurements of leukotriene E4 and N-acetyl-leukotriene E4 in urine. A marked increase of renal cysteinyl leukotriene excretion was observed in patients with cirrhosis without and with ascites, intrahepatic cholestasis, and obstructive jaundice as compared with healthy subjects (leukotriene E4: means 82, 264, 221 and 142 versus 40 nmol/mol creatinine, respectively; N-acetyl-leukotriene E4: means 25, 64, 61 and 47 versus 13 nmol/mol creatinine, respectively). The urinary concentration of leukotriene E4 was positively correlated with the one of N-acetyl-leukotriene E4 (r = 0.81, p jaundice, the excretion of leukotriene E4 plus N-acetyl-leukotriene E4 was positively correlated with total serum bilirubin. In patients with cirrhosis and in those with obstructive jaundice, the cysteinyl leukotrienes in urine were negatively correlated with creatinine clearance. The elevated renal excretion of cysteinyl leukotrienes decreased after biliary drainage in patients with obstructive jaundice. These data support the concept that increased urinary excretion of cysteinyl leukotrienes in patients with cirrhosis is due to a reduced functional liver mass and that in patients with cholestasis it is mainly due to an impaired elimination into the biliary tract that results in a diversion to renal excretion.(ABSTRACT TRUNCATED AT 250 WORDS)

  11. Is there a role for leukotrienes as mediators of ethanol-induced gastric mucosal damage?

    International Nuclear Information System (INIS)

    Wallace, J.L.; Beck, P.L.; Morris, G.P.

    1988-01-01

    The role of leukotriene (LT) C 4 as a mediator of ethanol-induced gastric mucosal damage was investigated. Rats were pretreated with a number of compounds, including inhibitors of leukotriene biosynthesis and agents that have previously been shown to reduce ethanol-induced damage prior to oral administration of absolute ethanol. Ethanol administration resulted in a fourfold increase in LTC 4 synthesis. LTC 4 synthesis could be reduced significantly by pretreatment with L651,392 or dexamethosone without altering the susceptibility of the gastric mucosa to ethanol-induced damage. Furthermore, changes in LBT 4 synthesis paralleled the changes in LTC 4 synthesis observed after ethanol administration. The effects of ethanol on gastric eicosanoid synthesis were further examined using an ex vivo gastric chamber preparation that allowed for application of ethanol to only one side of the stomach. These studies confirm that ethanol can stimulate gastric leukotriene synthesis independent of the production of hemorrhagic damage. Inhibition of LTC 4 synthesis does not confer protection to the mucosa, suggesting that LTC 4 does not play an important role in the etiology of ethanol-induced gastric damage

  12. Cysteinyl leukotrienes C4 and D4 downregulate human mast cell expression of toll-like receptors 1 through 7.

    Science.gov (United States)

    Karpov, V; Ilarraza, R; Catalli, A; Kulka, M

    2018-01-01

    Cysteinyl leukotrienes (CysLT) are potent inflammatory lipid molecules that mediate some of the pathophysiological responses associated with asthma such as bronchoconstriction, vasodilation and increased microvascular permeability. As a result, CysLT receptor antagonists (LRA), such as montelukast, have been used to effectively treat patients with asthma. We have recently shown that mast cells are necessary modulators of innate immune responses to bacterial infection and an important component of this innate immune response may involve the production of CysLT. However, the effect of LRA on innate immune receptors, particularly on allergic effector cells, is unknown. This study determined the effect of CysLT on toll-like receptor (TLR) expression by the human mast cell line LAD2. Real-time PCR analysis determined that LTC4, LTD4 and LTE4 downregulated mRNA expression of several TLR. Specifically in human CD34+-derived human mast cells (HuMC), LTC4 inhibited expression of TLR1, 2, 4, 5, 6 and 7 while LTD4 inhibited expression of TLR1-7. Montelukast blocked LTC4-mediated downregulation of all TLR, suggesting that these effects were mediated by activation of the CysLT1 receptor (CysLT1R). Flow cytometry analysis confirmed that LTC4 downregulated surface expression of TLR2 which was blocked by montelukast. These data show that CysLT can modulate human mast cell expression of TLR and that montelukast may be beneficial for innate immune responses mediated by mast cells.

  13. Pathophysiology of the cysteinyl leukotrienes and effects of leukotriene receptor antagonists in asthma

    DEFF Research Database (Denmark)

    Bisgaard, H

    2001-01-01

    , exudation of macromolecules and edema. The cysteinyl leukotrienes also have potent chemoattractant properties for eosinophils, causing an influx of eosinophils into the airway mucosa, which further fuels the inflammatory process. In addition, the cysteinyl leukotrienes are potent secretagogues and reduce...... and pranlukast inhibit bronchoconstriction in asthmatic patients undergoing allergen, exercise, cold air or aspirin challenge. They attenuate the hallmarks of asthmatic inflammation, including eosinophilia in the airway mucosa and peripheral blood. Moreover, exhaled nitric oxide concentrations, another correlate...

  14. The inflammatory mediator leukotriene D4 induces subcellular β-catenin translocation and migration of colon cancer cells

    International Nuclear Information System (INIS)

    Salim, Tavga; Sand-Dejmek, Janna; Sjölander, Anita

    2014-01-01

    The abnormal activation of the Wnt/β-catenin pathway frequently occurs in colorectal cancer. The nuclear translocation of β-catenin activates the transcription of target genes that promote cell proliferation, survival, and invasion. The pro-inflammatory mediator leukotriene D 4 (LTD 4 ) exerts its effects through the CysLT 1 receptor. We previously reported an upregulation of CysLT 1 R in patients with colon cancer, suggesting the importance of leukotrienes in colon cancer. The aim of this study was to investigate the impact of LTD 4 on Wnt/β-catenin signaling and its effects on proliferation and migration of colon cancer cells. LTD 4 stimulation led to an increase in β-catenin expression, β-catenin nuclear translocation and the subsequent transcription of MYC and CCND1. Furthermore, LTD 4 significantly reduced the expression of E-cadherin and β-catenin at the plasma membrane and increased the migration and proliferation of HCT116 colon cancer cells. The effects of LTD 4 can be blocked by the inhibition of CysLT 1 R. Furthermore, LTD 4 induced the inhibition of glycogen synthase kinase 3 (GSK)-3β activity, indicating a crosstalk between the G-protein-coupled receptor CysLT 1 and the Wnt/β-catenin pathway. In conclusion, LTD 4 , which can be secreted from macrophages and leukocytes in the tumor microenvironment, induces β-catenin translocation and the activation of β-catenin target genes, resulting in the increased proliferation and migration of colon cancer cells. - Highlights: • Leukotriene D 4 (LTD 4 ) lowers membrane β-catenin but increases nuclear β-catenin levels in colon cancer cells. • In agreement, LTD 4 triggers inactivation of GSK-3β, activation of TCF/LEF and increased expression of Cyclin D1 and c-Myc. • LTD 4 also caused a significant reduction in the expression of E-cadherin and an increased migration of colon cancer cells

  15. Cold injury, blood-brain barrier changes, and leukotriene synthesis: Inhibition by phenidone

    International Nuclear Information System (INIS)

    Robichaud, L.J.; Marcoux, F.W.

    1990-01-01

    Transcranial cold injury in rats and guinea pigs induced cerebral extravasation of albumin labeled with Evans blue dye or 125 I, respective indicators of the area and amount of blood-brain barrier (BBB) disruption. Radioimmunoassay of brain extracts showed that cold injury induced leukotriene (LT)C4 in rat and guinea pig brains 15 min after injury. In guinea pigs, the LT synthesis inhibitor phenidone (30 mg/kg, i.p.) completely blocked cold-induced LTC4 in brain. Phenidone (30 and 100 mg/kg) also inhibited cerebral tissue accumulation of 125 I-albumin and dye in rats and guinea pigs. Phenidone is reported to show antioxidant properties and selective lipoxygenase inhibition of arachidonic acid metabolism compared to cyclooxygenase inhibitors, meclofenamate sodium, and other nonsteroidal anti-inflammatory agents. Since several oxygen and hydroxyl radical scavengers and the cyclooxygenase inhibitor, meclofenamate sodium, did not inhibit protein extravasation, the findings support a role for LT as a mediator of cold-induced changes in BBB permeability in rats and guinea pigs and suggest that the inhibitory effects of phenidone on BBB permeability may be due to inhibition of LT production

  16. Increase in salivary cysteinyl-leukotriene concentration in patients with aspirin-intolerant asthma.

    Science.gov (United States)

    Ono, Emiko; Taniguchi, Masami; Higashi, Noritaka; Mita, Haruhisa; Yamaguchi, Hiromichi; Tatsuno, Sayaka; Fukutomi, Yuma; Tanimoto, Hidenori; Sekiya, Kiyoshi; Oshikata, Chiyako; Tsuburai, Takahiro; Tsurikisawa, Naomi; Otomo, Mamoru; Maeda, Yuji; Hasegawa, Maki; Miyazaki, Eishi; Kumamoto, Toshihide; Akiyama, Kazuo

    2011-03-01

    Cysteinyl-leukotrienes (CysLTs; LTC4, LTD4, and LTE4) play a considerable role in the pathophysiology of aspirin-intolerant asthma (AIA). Saliva has recently been validated as novel, simple, and noninvasive method for investigating inflammation in patients with asthma. The aim of this study is to clarify the molecular species of CysLT in saliva and to evaluate the CysLT and LTB4 concentrations in saliva in AIA patients. We also examined how the CysLT concentration in saliva reflects that of their corresponding urinary metabolite. We preformed an analytical cross-sectional study. CysLT and LTB4 concentrations in saliva were quantified by enzyme immunoassay (EIA) following purification by high-performance liquid chromatography (HPLC). 1. When analyzed by EIA in combination with HPLC, saliva was found to consist of LTC4, LTD4 and LTE4 in similar amounts. 2. In saliva analysis among the three groups (AIA patients, aspirin-tolerant asthma [ATA] patients, and healthy subjects), both the concentrations of CysLTs and LTB4 were significantly higher in AIA patients than in ATA patients and healthy subjects. 3. We found significant correlations between CysLT concentration and LTB4 concentration in saliva in each group. 4. No significant correlation was found between the concentration of LTE4 in urine and that of CysLTs in saliva. In this study, we found higher concentrations of CysLTs and LTB4 in saliva from AIA patients than in saliva from ATA patients, suggesting that the quantification of CysLT and LTB4 concentrations in saliva may be another diagnostic strategy for AIA.

  17. A possible role for cysteinyl-leukotrienes in non-ionic contrast media induced adverse reactions

    Energy Technology Data Exchange (ETDEWEB)

    Boehm, Ingrid [Department of Radiology, University of Bonn, Sigmund Freud Strasse 25, 53105 Bonn (Germany)]. E-mail: i.boehm@uni-bonn.de; Speck, Ulrich [Department of Radiology, Humboldt University (Charite) of Berlin (Germany); Schild, Hans [Department of Radiology, University of Bonn, Sigmund Freud Strasse 25, 53105 Bonn (Germany)

    2005-09-01

    Purpose: To test whether mono- or dimeric X-ray contrast media (CM) may induce the de novo production of cysteinyl-leukotriens (cys-LT), that could contribute to allergic/allergy-like side effects. Materials and methods: Leukocytes from 39 patients receiving iopromide or iotrolan for routine CT-examination were analyzed for the production of cys-LT. Histamine levels were analyzed in plasma specimens. One patient with a positive history of a previous CM-reaction did not receive CM-injection. Results: Three patients of the iopromide and five of the iotrolan group showed adverse reactions. Reactors had increased cys-LT values in samples obtained before CM-injection induced by the positive control (anti-Fc{epsilon}RI antibodies) (6763.7 pg/ml {+-} 1367.3 versus 2299.8 pg/ml {+-} 399.2; p < 0.007). Patients with versus without CM-reaction did not differ significantly with respect to their histamine values before CM-administeration. In vitro iopromide (p < 0.0002) and iotrolan (p < 0.0008) induced significant cys-LT production as compared to IL-3 stimulation. In vivo both CM induced a significant increase 6 h after CM administration (p < 0.05). Conclusion: Our findings suggest that both CM seem to induce cys-LT production. As to whether the observed increased values in pre-dose samples of patients with as compared to those without reactions could contribute to identify high risk patients should be investigated in larger patient groups in future.

  18. A possible role for cysteinyl-leukotrienes in non-ionic contrast media induced adverse reactions

    International Nuclear Information System (INIS)

    Boehm, Ingrid; Speck, Ulrich; Schild, Hans

    2005-01-01

    Purpose: To test whether mono- or dimeric X-ray contrast media (CM) may induce the de novo production of cysteinyl-leukotriens (cys-LT), that could contribute to allergic/allergy-like side effects. Materials and methods: Leukocytes from 39 patients receiving iopromide or iotrolan for routine CT-examination were analyzed for the production of cys-LT. Histamine levels were analyzed in plasma specimens. One patient with a positive history of a previous CM-reaction did not receive CM-injection. Results: Three patients of the iopromide and five of the iotrolan group showed adverse reactions. Reactors had increased cys-LT values in samples obtained before CM-injection induced by the positive control (anti-FcεRI antibodies) (6763.7 pg/ml ± 1367.3 versus 2299.8 pg/ml ± 399.2; p < 0.007). Patients with versus without CM-reaction did not differ significantly with respect to their histamine values before CM-administeration. In vitro iopromide (p < 0.0002) and iotrolan (p < 0.0008) induced significant cys-LT production as compared to IL-3 stimulation. In vivo both CM induced a significant increase 6 h after CM administration (p < 0.05). Conclusion: Our findings suggest that both CM seem to induce cys-LT production. As to whether the observed increased values in pre-dose samples of patients with as compared to those without reactions could contribute to identify high risk patients should be investigated in larger patient groups in future

  19. Effects of menadione, a reactive oxygen generator, on leukotriene secretion from RBL-2H3 cells.

    Science.gov (United States)

    Kawamura, Fumio; Nakanishi, Mamoru; Hirashima, Naohide

    2010-01-01

    Reactive oxygen species (ROS) are produced in various cells and affect many biological processes. We previously reported that 2-methyl-1,4-naphtoquinone (menadione) inhibited Ca(2+) influx from the extracellular medium and exocytosis evoked by antigen stimulation in the mast cell line, RBL-2H3. Mast cells release various inflammatory mediators such as leukotrienes (LTs) and cytokines in addition to the exocytotic secretion of histamine. In this study, we investigated the effects of menadione on LT release in RBL-2H3. Treatment of RBL cells with menadione inhibited LTC(4) secretion induced by antigen stimulation. To elucidate the mechanism of this inhibition, we examined the effects of menadione on the activation process of 5-lipoxygenase that is responsible for the synthesis of LTs from arachidonic acid. Menadione did not affect the phosophorylation of mitogen activated protein (MAP) kinases, extracellular signal-regulated kinase (ERK) and p38, which regulates phosphorylation of 5-lipoxygenase. However, menadione inhibited the translocation of 5-lipoxygenase from the cytoplasm to the nuclear membrane. Together with the result that LT secretion was severely impaired in the absence of extracellular Ca2(2+), it is suggested that ROS produced by menadione inhibited LT secretion through impaired Ca2(2+) influx and 5-lipoxygenase translocation to the nuclear membrane.

  20. Leukotrienes are upregulated and associated with human T-lymphotropic virus type 1 (HTLV-1-associated neuroinflammatory disease.

    Directory of Open Access Journals (Sweden)

    Bruno Caetano Trindade

    Full Text Available Leukotrienes (LTs are lipid mediators involved in several inflammatory disorders. We investigated the LT pathway in human T-lymphotropic virus type 1 (HTLV-1 infection by evaluating LT levels in HTLV-1-infected patients classified according to the clinical status as asymptomatic carriers (HACs and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP patients. Bioactive LTB(4 and CysLTs were both increased in the plasma and in the supernatant of peripheral blood mononuclear cell cultures of HTLV-1-infected when compared to non-infected. Interestingly, CysLT concentrations were increased in HAM/TSP patients. Also, the concentration of plasma LTB(4 and LTC(4 positively correlated with the HTLV-1 proviral load in HTLV-1-infected individuals. The gene expression levels of LT receptors were differentially modulated in CD4(+ and CD8(+ T cells of HTLV-1-infected patients. Analysis of the overall plasma signature of immune mediators demonstrated that LT and chemokine amounts were elevated during HTLV-1 infection. Importantly, in addition to CysLTs, IP-10 was also identified as a biomarker for HAM/TSP activity. These data suggest that LTs are likely to be associated with HTLV-1 infection and HAM/TSP development, suggesting their putative use for clinical monitoring.

  1. Inhibitory activity of tryptanthrin on prostaglandin and leukotriene synthesis.

    Science.gov (United States)

    Danz, Henning; Stoyanova, Stefka; Thomet, Olivier A R; Simon, Hans-Uwe; Dannhardt, Gerd; Ulbrich, Holger; Hamburger, Matthias

    2002-10-01

    The indolo[2,1- b]quinazoline alkaloid tryptanthrin has previously been identified as the cyclooxygenase-2 (COX-2) inhibitory principle in the extract ZE550 prepared from the medicinal plant Isatis tinctoria (Brassicaceae). We here investigated the potential inhibitory activity of tryptanthrin and ZE550 on COX-2, COX-1 in cellular and cell-free systems. A certain degree of selectivity towards COX-2 was observed when COX-1-dependent formation of thromboxane B(2) (TxB(2)) in HEL cells and COX-2-dependent formation of 6-ketoprostaglandin F(1alpha) (6-keto-PGF(1alpha)) in Mono Mac 6 and RAW 264.7 cells were compared. Preferential inhibition of COX-2 by two orders of magnitude was found in phorbol myristate acetate (PMA) activated bovine aortic coronary endothelial cells (BAECs). Assays with purified COX isoenzymes from sheep confirmed the high selectivity towards COX-2. The leukotriene B(4) (LTB(4)) release from calcium ionophore-stimulated human granulocytes (neutrophils) was used as a model to determine 5-lipoxygenase (5-LOX) activity. Tryptanthrin and the extract ZE550 inhibited LTB(4) release in a dose dependent manner and with a potency comparable to that of the clinically used 5-LOX inhibitor zileuton.

  2. Significance of production of peptide leukotrienes in murine traumatic shock

    International Nuclear Information System (INIS)

    Craft, D.V.; Lefer, D.J.; Hock, C.E.; Lefer, A.M.

    1986-01-01

    The authors studied the formation of a leukotriene metabolite in plasma and bile during traumatic shock. Anesthetized rats subjected to Noble-Collip drum trauma developed a lethal shock state characterized by a survival time of 1.9 +/- 0.3h, a 4.5-fold increase in plasma cathepsin D activity, and a reduction in mean arterial blood pressure to 45 +/- 2 mmHg compared with 108 +/- 5 mmHg in sham-shock controls. Plasma and bile samples were analyzed by reverse-phase high-pressure liquid chromatography (HPLC) for peptide leukotrienes, and their retention times were confirmed by co-elution with radioactive standards, radioimmunoassay (RIA), and UV spectrophotometry. No leukotrienes or metabolites were found in plasma. The major peptide leukotriene from bile was eluted between LTC 4 and LTD 4 and corresponds to a metabolite of LTE 4 , N-acetyl-LTE 4 , which is also produced during endotoxin shock. The metabolite increased nearly sevenfold in traumatic shock compared with sham trauma. The identity of the metabolite was confirmed by UV scan, which revealed a spectrum consistent with a peptide leukotriene and similar to that of previously reported spectra for N-acetyl-LTE 4 . In conclusion, peptide leukotrienes are rapidly cleared from the blood and appear in the bile as N-acetyl-LTE 4 , a metabolite of the peptide leukotrienes. These findings support a role of the peptide leukotrienes in the pathogenesis of traumatic shock

  3. Bronchial effects of leukotriene D4 inhalation in normal human lung

    DEFF Research Database (Denmark)

    Bisgaard, H; Groth, S

    1987-01-01

    airways in asthmatic patients out of attack. LTD4 caused a dose-dependent obstruction of the airways as measured by partial flow-volume curves and volume of trapped gas, yet only minor changes in forced expiratory volume in 1 s (FEV1) and peak expiratory flow rate. LTD4 was 1900-7000 times more potent......The aim of the study was to investigate whether inhaled leukotriene (LT) D4 could mimic the characteristics of asthmatic patients after allergen-induced attack, i.e. a prolonged subclinical bronchial obstruction, an increased reactivity of the airways and a late reaction. The effects of LTD4 were...... than histamine. LTD4 inhalations were almost symptomless as opposed to the irritative and dyspnoeic symptoms seen after inhalation of histamine. The time duration for the induced change in partial flow-volume curves was the same for the two drugs. Approximately 30 min elapsed until the bronchial...

  4. Release of leukotriene C4 from human polymorphonuclear leucocytes as determined by radioimmunoassay

    International Nuclear Information System (INIS)

    Aehringhaus, U.; Woelbling, R.H.; Peskar, B.M.; Peskar, B.A.; Koenig, W.; Patrono, C.

    1982-01-01

    Rabbits were immunized with a conjugate of leukotriene (LT)C 4 and bovine serum albumin prepared by coupling the single free amino group of the hapten to the protein using gluteraldehyde. Binding of [ 3 H]LTC 4 to the antibodies obtained is inhibited by 50% with 1.5 ng LTC 4 . The relative cross-section of LTD 4 is 16% and of LTC 4 -methyl ester 3.6%. The validity of the radioimmunoassay was demonstrated by comparison with bioassay using the isolated guinea pig ileum. Using the radioimmunoassay it could be shown that endogenous LTC 4 is released in a dose-dependent manner by human polymorphonuclear leucocytes stimulated with the divalent cation ionophore A23187. (Auth.)

  5. The inflammatory mediator leukotriene D{sub 4} induces subcellular β-catenin translocation and migration of colon cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Salim, Tavga [Division of Cell and Experimental Pathology, Department of Laboratory Medicine, Lund University, Clinical Research Center, Skåne University Hospital, Malmö (Sweden); Sand-Dejmek, Janna [Division of Cell and Experimental Pathology, Department of Laboratory Medicine, Lund University, Clinical Research Center, Skåne University Hospital, Malmö (Sweden); Section of Surgery, Department of Clinical Sciences, Lund University, Skåne University Hospital, Malmö (Sweden); Bayer HealthCare, Pharmaceuticals Medical Affairs, Solna (Sweden); Sjölander, Anita, E-mail: anita.sjolander@med.lu.se [Division of Cell and Experimental Pathology, Department of Laboratory Medicine, Lund University, Clinical Research Center, Skåne University Hospital, Malmö (Sweden)

    2014-02-15

    The abnormal activation of the Wnt/β-catenin pathway frequently occurs in colorectal cancer. The nuclear translocation of β-catenin activates the transcription of target genes that promote cell proliferation, survival, and invasion. The pro-inflammatory mediator leukotriene D{sub 4} (LTD{sub 4}) exerts its effects through the CysLT{sub 1} receptor. We previously reported an upregulation of CysLT{sub 1}R in patients with colon cancer, suggesting the importance of leukotrienes in colon cancer. The aim of this study was to investigate the impact of LTD{sub 4} on Wnt/β-catenin signaling and its effects on proliferation and migration of colon cancer cells. LTD{sub 4} stimulation led to an increase in β-catenin expression, β-catenin nuclear translocation and the subsequent transcription of MYC and CCND1. Furthermore, LTD{sub 4} significantly reduced the expression of E-cadherin and β-catenin at the plasma membrane and increased the migration and proliferation of HCT116 colon cancer cells. The effects of LTD{sub 4} can be blocked by the inhibition of CysLT{sub 1}R. Furthermore, LTD{sub 4} induced the inhibition of glycogen synthase kinase 3 (GSK)-3β activity, indicating a crosstalk between the G-protein-coupled receptor CysLT{sub 1} and the Wnt/β-catenin pathway. In conclusion, LTD{sub 4}, which can be secreted from macrophages and leukocytes in the tumor microenvironment, induces β-catenin translocation and the activation of β-catenin target genes, resulting in the increased proliferation and migration of colon cancer cells. - Highlights: • Leukotriene D{sub 4} (LTD{sub 4}) lowers membrane β-catenin but increases nuclear β-catenin levels in colon cancer cells. • In agreement, LTD{sub 4} triggers inactivation of GSK-3β, activation of TCF/LEF and increased expression of Cyclin D1 and c-Myc. • LTD{sub 4} also caused a significant reduction in the expression of E-cadherin and an increased migration of colon cancer cells.

  6. Implementation of LT codes based on chaos

    International Nuclear Information System (INIS)

    Zhou Qian; Li Liang; Chen Zengqiang; Zhao Jiaxiang

    2008-01-01

    Fountain codes provide an efficient way to transfer information over erasure channels like the Internet. LT codes are the first codes fully realizing the digital fountain concept. They are asymptotically optimal rateless erasure codes with highly efficient encoding and decoding algorithms. In theory, for each encoding symbol of LT codes, its degree is randomly chosen according to a predetermined degree distribution, and its neighbours used to generate that encoding symbol are chosen uniformly at random. Practical implementation of LT codes usually realizes the randomness through pseudo-randomness number generator like linear congruential method. This paper applies the pseudo-randomness of chaotic sequence in the implementation of LT codes. Two Kent chaotic maps are used to determine the degree and neighbour(s) of each encoding symbol. It is shown that the implemented LT codes based on chaos perform better than the LT codes implemented by the traditional pseudo-randomness number generator. (general)

  7. A role for inflammatory mediators in heterologous desensitization of CysLT1 receptor in human monocytes

    Science.gov (United States)

    Capra, Valérie; Accomazzo, Maria Rosa; Gardoni, Fabrizio; Barbieri, Silvia; Rovati, G. Enrico

    2010-01-01

    Cysteinyl-leukotrienes (cysteinyl-LT) are rapidly generated at sites of inflammation and, in addition to their role in asthma, rhinitis, and other immune disorders, are increasingly regarded as significant inflammatory factors in cancer, gastrointestinal, cardiovascular diseases. We recently demonstrated that in monocyte/macrophage–like U937 cells, extracellular nucleotides heterologously desensitize CysLT1 receptor (CysLT1R)-induced Ca2+ transients. Given that monocytes express a number of other inflammatory and chemoattractant receptors, this study was aimed at characterizing transregulation between these different stimuli. We demonstrate that in U937 cells and in primary human monocytes, a series of inflammatory mediators activating Gi-coupled receptor (FPR1, BLT1) desensitize CysLT1R-induced Ca2+ response unidirectionally through activation of PKC. Conversely, PAF-R, exclusively coupled to Gq, cross-desensitizes CysLT1R without the apparent involvement of any kinase. Interestingly, Gs-coupled receptors (β2AR, H1/2R, EP2/4R) are also able to desensitize CysLT1R response through activation of PKA. Heterologous desensitization seems to affect mostly the Gi-mediated signaling of the CysLT1R. The hierarchy of desensitization among agonists may be important for leukocyte signal processing at the site of inflammation. Considering that monocytes/macrophages are likely to be the major source of cysteinyl-LT in many immunological and inflammatory processes, shedding light on how their receptors are regulated will certainly help to better understand the role of these cells in orchestrating this complex network of integrated signals. PMID:19965602

  8. Leukotriene Receptor Antagonists in the Treatment of Asthma: Implications for Eosinophilic Inflammation

    Directory of Open Access Journals (Sweden)

    Redwan Moqbel

    1999-01-01

    Full Text Available Recent advances in the treatment and management of asthma have suggested that leukotriene (LT receptor antagonists may be very beneficial as a second generation therapy with steroid-sparing properties and negligible side effects. These agents have shown interesting effects on peripheral blood and sputum eosinophils. A major contributor to the damage in the airway of asthmatic patients is the eosinophil, which, upon activation, releases a battery of granule-associated cytotoxic, cationic proteins, including the major basic protein and eosinophil peroxidase, and membrane-derived de novo-synthesized bioactive lipid mediators, including LTC4, LTD4 and LTE4, as well as platelet activating factor. These products have deleterious effects on the airway tissue including mucosal and smooth muscle layers. Accumulating evidence suggests that these agents may also influence the accumulation and maintenance of eosinophilic responses at the site of inflammation. This article reviews the possible anti-inflammatory mode of action of these therapies. It also discusses where there may be a gap in the knowledge regarding the potential direct and indirect effects of LT modifiers on eosinophil function and recruitment.

  9. 15 CFR 8b.4 - Discrimination prohibited.

    Science.gov (United States)

    2010-01-01

    ... 15 Commerce and Foreign Trade 1 2010-01-01 2010-01-01 false Discrimination prohibited. 8b.4 Section 8b.4 Commerce and Foreign Trade Office of the Secretary of Commerce PROHIBITION OF DISCRIMINATION... Provisions § 8b.4 Discrimination prohibited. (a) General. No qualified handicapped individual shall, on the...

  10. 7 CFR 15b.4 - Discrimination prohibited.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 1 2010-01-01 2010-01-01 false Discrimination prohibited. 15b.4 Section 15b.4... ACTIVITIES RECEIVING FEDERAL FINANCIAL ASSISTANCE General Provisions § 15b.4 Discrimination prohibited. (a... in, be denied the benefits of, or otherwise be subjected to discrimination under any program or...

  11. Selective blockade of leukotriene production by a single dose of the FPL 64170XX 0.5% enema in active ulcerative colitis

    DEFF Research Database (Denmark)

    Kjeldsen, J; Laursen, L S; Hillingsø, Jens

    1995-01-01

    5-Lipoxygenase products of arachidonic acid metabolism are thought to play a central role in the secondary amplification of the inflammatory response of several inflammatory diseases, including ulcerative colitis. FPL 64170XX is a selective inhibitor of the enzyme 5-lipoxygenase. Concentrations...... containing 0.5% of FPL 64170XX. Repeated measures analysis of leukotriene B4, after adjusting for baseline, showed a significant treatment effect (P = 0.0014). The concentration of leukotriene B4 from rectal dialysates in patients receiving the active drug dropped to 15% (95% confidence interval 5......-40%) of the placebo level in the second dialysis following administration of FPL 64170XX 0.5%. By contrast, prostaglanding E2 concentrations doubled (P = 0.0068) in patients receiving FPL 64170XX 0.5% with no change in the placebo group. These findings demonstrate that a single dose of FPL 64170XX 0.5% enema...

  12. Solubilization and cleavage of human neutrophil (N) affinity-labeled receptors for leukotriene B4 (LTB4)

    International Nuclear Information System (INIS)

    Marotti, T.; Young, R.N.; Gifford, L.A.; Goldman, D.W.; Goetzl, E.J.

    1986-01-01

    LTB 4 chemotactic receptors in purified N plasma membranes (PMs) have been affinity-labeled with [ 3 H]-C-1 aminopropylamide-LTB 4 ([ 3 H]APA-LTB 4 ) by disuccinimidyl suberate (DSS) cross-linking. Intact Ns were pretreated with diisopropylfluorophosphate, suspended at 10 7 /ml in Hanks' solution-10 mM HEPES (pH 7.4), incubated for 30 min at 4 0 C with 30 nM [ 3 H]APA-LTB 4 and 25 min with 1 mM bis[2-(succinimidooxycarbonyloxy)-ethyl] sulfone, an impermeant analog of DSS, and sonified for 30 sec at 4 0 C. The 10,000 g supernatant of the sonicate was centrifuged at 40,000 g for 30 min at 4 0 C on a discontinuous gradient of 10-50 g % sucrose, from which a mean of 78% of the radiolabel was recovered with PM markers. The extent and specificity of labeling of intact N receptors were similar to those of receptors in PMs. The radioactively-labeled receptors appeared as a single band of 35-40 kd in sodium dodecyl sulfate (SDS) 10 g % polyacrylamide gel electrophoresis. Cleavage of radiolabeled receptors with 1 mg/ml of cyanogen bromide in 70% formic acid for 18 hr at room temperature or with 30 mM HCl under N 2 for 4 hr at 105 0 C converted a mean of 18-32% of the radioactivity to a band of 14 kd in SDS-15 g % PAGE. N receptors for LTB 4 , thus, are localized in the PM and can be isolated for structural studies

  13. Inhibition of In Vitro Leukotriene B-4 Biosynthesis in Human Neutrophil Granulocytes and Docking Studies of Natural Quinones

    Czech Academy of Sciences Publication Activity Database

    Landa, Přemysl; Kutil, Zsófia; Temml, V.; Malík, J.; Kokoška, L.; Widowitz, U.; Přibylová, Marie; Dvořáková, Marcela; Maršík, Petr; Schuster, D.; Bauer, R.; Vaněk, Tomáš

    2013-01-01

    Roč. 8, č. 1 (2013), s. 105-108 ISSN 1934-578X R&D Projects: GA ČR GP525/09/P528; GA MŠk(CZ) MEB061112 Institutional research plan: CEZ:AV0Z50380511 Keywords : 5-Lipoxygenase * Anti-inflammatory activity * Dual COX /LOX inhibition Subject RIV: GM - Food Processing Impact factor: 0.924, year: 2013

  14. Leukotriene B4 (LTB4) induces formation of inositol-phosphates (IP's) in rat peritoneal polymorphonuclear leukocytes (PMN's)

    International Nuclear Information System (INIS)

    Chi-Rosso, G.; Crooke, S.T.; Mong, S.

    1986-01-01

    LTB 4 induced rapid breakdown of prelabeled inositol-phospholipids (PI) in rat PMN. Formation of [ 3 H]-inositol-trisphosphate ([ 3 H]-IP 3 ) was rapid, with a peak of 250-300% of the control level, after 5-15 sec of stimulation with LTB 4 . Accumulation of [ 3 H]-inositol-bisphosphate ([ 3 H]-IP 2 ) was rapid, peaking after 30 sec of stimulation. [ 3 H]-inositol-monophosphate ([ 3 H]-IP 1 ) accumulated gradually in the presence of LiCl. The kinetics of [ 3 H]-IP 3 , [ 3 H]-IP 2 and [ 3 H]-IP 1 accumulation suggested that LTB 4 may interact with receptors in PMNs, activate phospholipase C which, in turn, induces hydrolysis of PI. The agonist activities of several LTB 4 analogs were employed to investigate the structure activity relationship of LTB 4 receptor mediated activation of PI hydrolysis. Increases in [ 3 H]-IP 3 formation were dependent upon the concentration of LTB 4 and the agonist analogs. The rank order potency of these analogs were equivalent to that of the pharmacological activity of LTB 4 agonists in the chemotaxis assay. Furthermore, the Islet activation protein (IAP) inhibited LTB 4 induced [ 3 H]-IP 3 formation. The tumor promoting phorbomyristate ester also inhibited LTB 4 induced [ 3 H]-IP 3 formation. These results suggest LTB 4 may interact with receptors in rat PMNs, activate G/sub i/ protein regulated phospholipase C and induce [ 3 H]-IP 3 formation

  15. TEO LT hakkab kaotama atraktiivsust / Romet Kreek

    Index Scriptorium Estoniae

    Kreek, Romet, 1972-

    2011-01-01

    Autori sõnul on Leedu telekomiettevõtte TEO LT puhul raske oodata, et käive ja kasum kasvaksid, parimal juhul on need stabiilsed. Osalt on selle põhjuseks tehnoloogilised muutused, osalt suuromaniku poliitika. TEO LT I kvartali majandusnäitajatest

  16. Resveratrol, a Red Wine Polyphenol, Suppresses Pancreatic Cancer by Inhibiting Leukotriene A4 Hydrolase

    Science.gov (United States)

    Oi, Naomi; Jeong, Chul-Ho; Nadas, Janos; Cho, Yong-Yeon; Pugliese, Angelo; Bode, Ann M.; Dong, Zigang

    2016-01-01

    The anticancer effects of red wine have attracted considerable attention. Resveratrol (3,5,4′-trihydroxy-trans-stilbene) is a well-known polyphenolic compound of red wine with cancer chemopreventive activity. However, the basis for this activity is unclear. We studied leukotriene A4 hydrolase (LTA4H) as a relevant target in pancreatic cancer. LTA4H knockdown limited the formation of leukotriene B4 (LTB4), the enzymatic product of LTA4H, and suppressed anchorage-independent growth of pancreatic cancer cells. An in silico shape similarity algorithm predicted that LTA4H might be a potential target of resveratrol. In support of this idea, we found that resveratrol directly bound to LTA4H in vitro and in cells and suppressed proliferation and anchorage-independent growth of pancreatic cancer by inhibiting LTB4 production and expression of the LTB4 receptor 1 (BLT1). Notably, resveratrol exerted relatively stronger inhibitory effects than bestatin, an established inhibitor of LTA4H activity, and the inhibitory effects of resveratrol were reduced in cells where LTA4H was suppressed by shRNA-mediated knockdown. Importantly, resveratrol inhibited tumor formation in a xenograft mouse model of human pancreatic cancer by inhibiting LTA4H activity. Our findings identify LTA4H as a functionally important target for mediating the anticancer properties of resveratrol. PMID:20952510

  17. PHARMACOGENOMICS OF PROSTAGLANDIN AND LEUKOTRIENE RECEPTORS

    Directory of Open Access Journals (Sweden)

    José Antonio Cornejo-García

    2016-09-01

    Full Text Available Individual genetic background together with environmental effects are thought to be behind many human complex diseases. A number of genetic variants, mainly single nucleotide polymorphisms (SNPs, have been shown to be associated with various pathological and inflammatory conditions, representing potential therapeutic targets. Prostaglandins (PTGs and leukotrienes (LTs are eicosanoids derived from arachidonic acid and related polyunsaturated fatty acids that participate in both normal homeostasis and inflammatory conditions. These bioactive lipid mediators are synthesised through two major multistep enzymatic pathways: PTGs by cyclooxygenase and LTs by 5-lipoxygenase. The main physiological effects of PTGs include vasodilation and vascular leakage (PTGE2; mast cell maturation, eosinophil recruitment and allergic responses (PTGD2; vascular and respiratory smooth muscle contraction (PTGF2, and inhibition of platelet aggregation (PTGI2. LTB4 is mainly involved in neutrophil recruitment, vascular leakage, and epithelial barrier function, whereas cysteinyl LTs (CysLTs (LTC4, LTD4 and LTE4 induce bronchoconstriction and neutrophil extravasation, and also participate in vascular leakage. PTGs and LTs exert their biological functions by binding to cognate receptors, which belong to the seven transmembrane, G protein-coupled receptor superfamily. SNPs in genes encoding these receptors may influence their functionality and have a role in disease susceptibility and drug treatment response. In this review we summarize SNPs in PTGs and LTs receptors and their relevance in human diseases. We also provide information on gene expression. Finally, we speculate on future directions for this topic.

  18. Leukotriene B₄-leukotriene B₄ receptor axis promotes oxazolone-induced contact dermatitis by directing skin homing of neutrophils and CD8⁺ T cells.

    Science.gov (United States)

    Lv, Jiaoyan; Zou, Linlin; Zhao, Lina; Yang, Wei; Xiong, Yingluo; Li, Bingji; He, Rui

    2015-09-01

    Leukotriene B4 (LTB4 ) is a lipid mediator that is rapidly generated in inflammatory sites, and its functional receptor, BLT1, is mostly expressed on immune cells. Contact dermatitis is a common inflammatory skin disease characterized by skin oedema and abundant inflammatory infiltrates, primarily including neutrophils and CD8(+) T cells. The role of the LTB4 -BLT1 axis in contact dermatitis remains largely unknown. In this study, we found up-regulated gene expression of 5-lipoxygenase and leukotriene A4 hydrolase, two critical enzymes for LTB4 synthesis, BLT1 and elevated LTB4 levels in skin lesions of oxazolone (OXA)-induced contact dermatitis. BLT1 deficiency or blockade of LTB4 and BLT1 by the antagonists, bestatin and U-75302, respectively, in the elicitation phase caused significant decreases in ear swelling and skin-infiltrating neutrophils and CD8(+) T cells, which was accompanied by significantly reduced skin expression of CXCL1, CXCL2, interferon-γ and interleukin-1β. Furthermore, neutrophil depletion during the elicitation phase of OXA-induced contact dermatitis also caused significant decreases in ear swelling and CD8(+) T-cell infiltration accompanied by significantly decreased LTB4 synthesis and gene expression of CXCL2, interferon-γ and interleukin-1β. Importantly, subcutaneous injection of exogenous LTB4 restored the skin infiltration of CD8(+) T cells in neutrophil-depleted mice following OXA challenge. Collectively, our results demonstrate that the LTB4 -BLT1 axis contributes to OXA-induced contact dermatitis by mediating skin recruitment of neutrophils, which are a major source of LTB4 that sequentially direct CD8(+) T-cell homing to OXA-challenged skin. Hence, LTB4 and BLT1 could be potential therapeutic targets for the treatment of contact dermatitis. © 2015 John Wiley & Sons Ltd.

  19. Endogenous leukotriene D4 formation during anaphylactic shock in the guinea pig

    International Nuclear Information System (INIS)

    Keppler, A.; Oerning, L.; Bernstroem, K.; Hammarstroem, S.

    1987-01-01

    Experiments on the metabolism and excretion of i.v. administered selectively labeled [ 3 H 8 ]leukotriene C 4 in bile duct-cannulated guinea pigs indicated predominantly biliary excretion of tritium. The major leukotriene metabolite in bile was identified as leukotriene D 4 . By monitoring leukotriene excretion radioimmunochromatographically, it was shown that guinea pigs suffering from anaphylactic shock produce leukotriene D 4 endogenously. Immunological challenge of animals sensitized to ovalbumin was accompanied by an increase of biliary leukotriene D 4 concentrations from 10 +/- 1 to 86 +/- 10 nM. When considering that bile flow was decreased to about half after challenge, the excretion rate of leukotriene D 4 in bile increased from 0.88 +/- 0.16 before 3.18 +/- 0.38 pmol x min -1 x kg -1 after challenge. It is concluded that systemic anaphylaxis in the guinea pig is associated with endogenous generation of leukotriene C 4

  20. 45 CFR 73b.4 - Proceedings.

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 1 2010-10-01 2010-10-01 false Proceedings. 73b.4 Section 73b.4 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL ADMINISTRATION DEBARMENT OR SUSPENSION OF FORMER EMPLOYEES... reasonable cause to believe that a former officer or employee, including a former special Government employee...

  1. Influence of leukotriene gene polymorphisms on chronic rhinosinusitis

    Directory of Open Access Journals (Sweden)

    Duval Melanie

    2008-03-01

    Full Text Available Abstract Background Chronic rhinosinusitis (CRS is increasingly viewed as an inflammatory condition of the sinonasal mucosa interacting with bacteria and/or fungi. However, factors conferring susceptibility to disease remain unknown. Advances in genomics offer powerful tools to explore this disorder. The goal of this study was to evaluate the effect of single nucleotide polymorphisms (SNP on CRS in a panel of genes related to cysteinyl leukotriene metabolism. Methods Severe cases of CRS and postal code match controls were recruited prospectively. A total of 206 cases and 200 controls were available for the present study. Using a candidate gene approach, five genes related to cysteinyl leukotriene metabolism were assessed. For each gene, we selected the maximally informative set of common SNPs (tagSNPs using the European-derived (CEU HapMap dataset. These SNPs are in arachidonate 5-lipoxygenase (ALOX5, arachidonate 5-lipoxygenase-activating protein (ALOX5AP, leukotriene C4 synthase (LTC4S, cysteinyl leukotriene receptor 1 (CYSLTR1 and cysteinyl leukotriene receptor 2 (CYSLTR2 genes. Results A total of 59 SNPs were genotyped to capture the common genetic variations within these genes. Three SNPs located within the ALOX5, CYSLTR1 and ALOX5AP genes reached the nominal p-value threshold (p Conclusion While these initial results do not support that polymorphsims in genes assessed involved in the leukotriene pathways are contributing to the pathogenesis of CRS, this initial study was not powered to detect polymorphisms with relative risk of 2.0 or less, where we could expect many gene effects for complex diseases to occur. Thus, despite this lack of significant association noted in this study, we believe that validation with external populations and the use of better-powered studies in the future may allow more conclusive findings.

  2. Effects of cysteinyl leukotrienes and leukotriene receptor antagonists on markers of inflammation

    DEFF Research Database (Denmark)

    Sampson, Anthony P; Pizzichini, Emilio; Bisgaard, Hans

    2003-01-01

    mediators in a wide range of diseases, implying that their biological activities reach far beyond acute bronchoconstriction, the activity traditionally ascribed to them. The validity of examining sputum for "biomarkers" has improved the understanding of asthma pathophysiology, optimization of asthma......The understanding that asthma pathophysiology includes an inflammatory component has spurred the more aggressive use of anti-inflammatory therapies and created a need for effective tools to measure inflammation. Biomarkers of airway inflammation proposed are obtained by methods that are direct...... but highly invasive (bronchial biopsy, bronchoalveolar lavage), moderately direct, and less invasive (indirect sputum, exhaled air, breath condensate) or indirect and least invasive (blood, urine). Several studies described in this review have implicated the cysteinyl leukotrienes (CysLTs) as inflammatory...

  3. Bronchoprotection with a leukotriene receptor antagonist in asthmatic preschool children

    DEFF Research Database (Denmark)

    Bisgaard, H; Nielsen, K G

    2000-01-01

    We hypothesized that a leukotriene receptor antagonist (LTRA) could provide bronchoprotection against the cold, dry air-induced response in asthmatic preschool children. In a randomized, double-blind, placebo-controlled crossover study, we examined the effect of the specific LTRA montelukast at 5...

  4. Characterization of arachidonate 5-lipoxygenase and leukotriene A4 synthetase from RBL-1 cells

    International Nuclear Information System (INIS)

    Cook, M.; Hogaboom, G.K.; Sarau, H.M.; Foley, J.J.; Crooke, S.T.

    1986-01-01

    5-lipoxygenase (LO) and leukotriene (LT) A4 synthetase from RBL-1 high speed (105,000 x g for 60 min) supernatants were partially purified by protein-high performance liquid chromatography (HPLC) and characterized in detail. The partially purified preparation contained only 5-LO and LTA4 synthetase and was isolated from 12-LO, peroxidase and LTA4 hydrolase activities. Reaction products were separated by reversed phase HPLC and quantitated by absorption spectrophotometry and radiochemical detection. The enzyme preparation rapidly converted [ 14 C]arachidonate to [ 14 C]5-hydroperoxyeicosatetraenoic acid (HPETE) and [ 14 C]5,12-dihydroperoxyeicosatetraenoic acids (diHETEs). The 5,12-diHETEs were primarily non-enzymatic breakdown products of LTA4 (e.g., 6-trans-LTB4 and 6-trans-12-epi-LTB4). Both the 5-LO and LTA4 synthetase activities were Ca 2+- and ATP-dependent. For both enzyme activities, the CA 2+ stimulation required the presence of ATP. The fatty acid hydroperoxides, 5-,12-, and 15-HPETE, both stimulated ([ 3 μM]) 5-LO and LTA4 synthetase activities. The rapid isolation and subsequent characterization of 5-LO and LTA4 synthetase provide the bases for the further understanding of the role of the LO pathway in biological processes

  5. Pharmacological modulation of human platelet leukotriene C4-synthase.

    Science.gov (United States)

    Sala, A; Folco, G; Henson, P M; Murphy, R C

    1997-03-21

    The aim of this study was to test if human platelet leukotriene C4-synthase (LTC4-S) is pharmacologically different from cloned and expressed LTC4-S and, in light of the significant homologies between 5-lipoxygenase activating protein (FLAP) and LTC4-S, if different potencies of leukotriene synthesis inhibitors acting through binding with FLAP (FLAP inhibitors) reflect in different potencies as LTC4-S inhibitors. Leukotriene C4 (LTC4) synthesis by washed human platelets supplemented with synthetic leukotriene A4 (LTA4) was studied in the absence and presence of two different, structurally unrelated FLAP inhibitors (MK-886 and BAY-X1005) as well as a direct 5-lipoxygenase inhibitor (zileuton). LTC4 production was analyzed by RP-HPLC coupled to diode array detection. We report that human platelet LTC4-S was inhibited by MK-886 and BAY-X1005 (IC50 of 4.7 microM and 91.2 microM, respectively), but not by zileuton (inactive up to 300 microM); all 3 compounds were able to inhibit 5-lipoxygenase metabolite biosynthesis in intact human polymorphonuclear leukocytes (IC50 of 0.044 microM, 0.85 microM, and 1.5 microM, respectively). Platelet LTC4-S does not appear pharmacologically different from expression cloned LTC4-S. LTC4-S inhibition by FLAP inhibitors is in agreement with the significant homology reported for expression-cloned LTC4-S with FLAP, Furthermore, functional homology of the binding sites for inhibitors on LTC4-S and FLAP is suggested by the conservation of the relative potencies of MK-886 and BAY-X1005 vs FLAP-dependent 5-lipoxygenase activity and LTC4-S inhibition: MK-886 was 19.3-fold more potent than BAY-X1005 as FLAP inhibitor and 19.6-fold more potent than BAY-X1005 as LTC4-S inhibitor.

  6. UEP LT Codes with Intermediate Feedback

    DEFF Research Database (Denmark)

    Sørensen, Jesper Hemming; Popovski, Petar; Østergaard, Jan

    2013-01-01

    We analyze a class of rateless codes, called Luby transform (LT) codes with unequal error protection (UEP). We show that while these codes successfully provide UEP, there is a significant price in terms of redundancy in the lower prioritized segments. We propose a modification with a single inter...... intermediate feedback message. Our analysis shows a dramatic improvement on the decoding performance of the lower prioritized segment....

  7. Combination L-T3 and L-T4 therapy for hypothyroidism.

    Science.gov (United States)

    Wartofsky, Leonard

    2013-10-01

    Because of the longstanding controversy regarding whether hypothyroid patients can be optimally replaced by treatment with levothyroxine (L-T4) alone, numerous studies have addressed potential benefits of combined therapy of triiodothyronine (T3) with L-T4. Results of these studies have failed to support a potential benefit of combined therapy. A strong argument for the addition of L-T3 to L-T4 monotherapy has been lacking until recent genetic studies indicated a rationale for such therapy among a small fraction of the hypothyroid patient population. Interest in this issue has focused on the importance of the deiodinases in maintaining the euthyroid state and the role of genetic polymorphisms in the deiodinase genes that would affect thyroid hormone concentrations in both blood and tissues. One such polymorphism in the D2 gene, Thr92Ala, is associated with reduced T4 to T3 activation in skeletal muscle and thyroid, linked to obesity and alterations in thyroid-pituitary feedback, and in responses to thyroid hormone treatment. Although our professional organizations continue to recommend L-T4 alone for the treatment of hypothyroidism, the possibility of a D2 gene polymorphism should be considered in patients on L-T4 monotherapy who continue to complain of fatigue in spite of dosage achieving low normal serum thyroid stimulating hormone levels. A suggestive clue to the presence of this polymorphism could be a higher than normal free T4/free T3 ratio. Clinicians could consider adding T3 as a therapeutic trial in selected patients. Future well controlled clinical trials will be required to more fully resolve the controversy.

  8. A geranyl acetophenone targeting cysteinyl leukotriene synthesis prevents allergic airway inflammation in ovalbumin-sensitized mice

    International Nuclear Information System (INIS)

    Ismail, Norazren; Jambari, Nuzul Nurahya; Zareen, Seema; Akhtar, Mohamad Nadeem; Shaari, Khozirah; Zamri-Saad, Mohamad; Tham, Chau Ling; Sulaiman, Mohd Roslan; Lajis, Nordin Hj; Israf, Daud Ahmad

    2012-01-01

    Asthma is associated with increased pulmonary inflammation and airway hyperresponsiveness. The current use of corticosteroids in the management of asthma has recently raised issues regarding safety and lack of responsiveness in 5–10% of asthmatic individuals. The aim of the present study was to investigate the therapeutic effect of a non-steroidal small molecule that has cysteinyl leukotriene (cysLT) inhibitory activity, upon attenuation of allergic lung inflammation in an acute murine model. Mice were sensitized with ovalbumin (OVA) and treated with several intraperitoneal doses (100, 20, 2 and 0.2 mg/kg) of 2,4,6,-trihydroxy-3-geranylacetophenone (tHGA). Bronchoalveolar lavage was performed, blood and lung samples were obtained and respiratory function was measured. OVA sensitization increased pulmonary inflammation and pulmonary allergic inflammation was significantly reduced at doses of 100, 20 and 2 mg/kg with no effect at the lowest dose of 0.2 mg/kg. The beneficial effects in the lung were associated with reduced eosinophilic infiltration and reduced secretion of Th2 cytokines and cysLTs. Peripheral blood reduction of total IgE was also a prominent feature. Treatment with tHGA significantly attenuated altered airway hyperresponsiveness as measured by the enhanced pause (Penh) response to incremental doses of methacholine. These data demonstrate that tHGA, a synthetic non-steroidal small molecule, can prevent acute allergic inflammation. This proof of concept opens further avenues of research and development of tHGA as an additional option to the current armamentarium of anti-asthma therapeutics. -- Highlights: ► Safer and effective anti-asthmatic drugs are in great demand. ► tHGA is a new 5-LO/cysLT inhibitor that inhibits allergic asthma in mice. ► tHGA is a natural compound that can be synthesized. ► Doses as low as 2 mg/kg alleviate lung pathology in experimental asthma. ► tHGA is a potential drug lead for the treatment of allergic asthma.

  9. Endogenous secreted phospholipase A2 group X regulates cysteinyl leukotrienes synthesis by human eosinophils.

    Science.gov (United States)

    Hallstrand, Teal S; Lai, Ying; Hooper, Kathryn A; Oslund, Rob C; Altemeier, William A; Matute-Bello, Gustavo; Gelb, Michael H

    2016-01-01

    Phospholipase A2s mediate the rate-limiting step in the formation of eicosanoids such as cysteinyl leukotrienes (CysLTs). Group IVA cytosolic PLA2α (cPLA2α) is thought to be the dominant PLA2 in eosinophils; however, eosinophils also have secreted PLA2 (sPLA2) activity that has not been fully defined. To examine the expression of sPLA2 group X (sPLA2-X) in eosinophils, the participation of sPLA2-X in the formation of CysLTs, and the mechanism by which sPLA2-X initiates the synthesis of CysLTs in eosinophils. Peripheral blood eosinophils were obtained from volunteers with asthma and/or allergy. A rabbit polyclonal anti-sPLA2-X antibody identified sPLA2-X by Western blot. We used confocal microscopy to colocalize the sPLA2-X to intracellular structures. An inhibitor of sPLA2-X (ROC-0929) that does not inhibit other mammalian sPLA2s, as well as inhibitors of the mitogen-activated kinase cascade (MAPK) and cPLA2α, was used to examine the mechanism of N-formyl-methionyl-leucyl-phenylalanine (fMLP)-mediated formation of CysLT. Eosinophils express the mammalian sPLA2-X gene (PLA2G10). The sPLA2-X protein is located in the endoplasmic reticulum, golgi, and granules of eosinophils and moves to the granules and lipid bodies during fMLP-mediated activation. Selective sPLA2-X inhibition attenuated the fMLP-mediated release of arachidonic acid and CysLT formation by eosinophils. Inhibitors of p38, extracellular-signal-regulated kinases 1/2 (p44/42 MAPK), c-Jun N-terminal kinase, and cPLA2α also attenuated the fMLP-mediated formation of CysLT. The sPLA2-X inhibitor reduced the phosphorylation of p38 and extracellular-signal-regulated kinases 1/2 (p44/42 MAPK) as well as cPLA2α during cellular activation, indicating that sPLA2-X is involved in activating the MAPK cascade leading to the formation of CysLT via cPLA2α. We further demonstrate that sPLA2-X is activated before secretion from the cell during activation. Short-term priming with IL-13 and TNF/IL-1β increased the

  10. Vascular effects of leukotriene D4 in human skin

    DEFF Research Database (Denmark)

    Bisgaard, H

    1987-01-01

    Leukotriene D4 (LTD4) increased the blood flow rate in human skin, equipotent to histamine in the dose range of 3.1-200 pmol. The vasodilatation lasted for up to 60 min, and no late reactions occurred. Indomethacin did not affect the LTD4-induced blood flow rate. H1 and H2 antagonists reduced...... as a mediator of the axon reflex, and show that LTD4 causes a direct vasodilatory effect that is not mediated via histamine or cyclooxygenase products. The laser-Doppler flowmeter was applied for dynamic studies of the vasopressor response in the skin during a Valsalva maneuver, and the relative changes...

  11. 26 CFR 1.167(b)-4 - Other methods.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 2 2010-04-01 2010-04-01 false Other methods. 1.167(b)-4 Section 1.167(b)-4...) INCOME TAXES (CONTINUED) Itemized Deductions for Individuals and Corporations § 1.167(b)-4 Other methods. (a) Under section 167(b)(4) a taxpayer may use any consistent method of computing depreciation, such...

  12. Lipoxin A4 stable analogs reduce allergic airway responses via mechanisms distinct from CysLT1 receptor antagonism.

    Science.gov (United States)

    Levy, Bruce D; Lukacs, Nicholas W; Berlin, Aaron A; Schmidt, Birgitta; Guilford, William J; Serhan, Charles N; Parkinson, John F

    2007-12-01

    Cellular recruitment during inflammatory/immune responses is tightly regulated. The ability to dampen inflammation is imperative for prevention of chronic immune responses, as in asthma. Here we investigated the ability of lipoxin A4 (LXA4) stable analogs to regulate airway responses in two allergen-driven models of inflammation. A 15-epi-LXA4 analog (ATLa) and a 3-oxa-15-epi-LXA4 analog (ZK-994) prevented excessive eosinophil and T lymphocyte accumulation and activation after mice were sensitized and aerosol-challenged with ovalbumin. At 50% and to a greater extent than equivalent doses of the CysLT1 receptor antagonist montelukast. Distinct from montelukast, ATLa treatment led to marked reductions in cysteinyl leukotrienes, interleukin-4 (IL-4), and IL-10, and both ATLa and ZK-994 inhibited levels of IL-13. In cockroach allergen-induced airway responses, both intraperitoneal and oral administration of ZK-994 significantly reduced parameters of airway inflammation and hyper-responsiveness in a dose-dependent manner. ZK-994 also significantly changed the balance of Th1/Th2-specific cytokine levels. Thus, the ATLa/LXA4 analog actions are distinct from CysLT1 antagonism and potently block both allergic airway inflammation and hyper-reactivity. Moreover, these results demonstrate these analogs' therapeutic potential as new agonists for the resolution of inflammation.

  13. Cysteinyl leukotriene E4 activates human group 2 innate lymphoid cells and enhances the effect of prostaglandin D2 and epithelial cytokines.

    Science.gov (United States)

    Salimi, Maryam; Stöger, Linda; Liu, Wei; Go, Simei; Pavord, Ian; Klenerman, Paul; Ogg, Graham; Xue, Luzheng

    2017-10-01

    Group 2 innate lymphoid cells (ILC2s) are a potential innate source of type 2 cytokines in the pathogenesis of allergic conditions. Epithelial cytokines (IL-33, IL-25, and thymic stromal lymphopoietin [TSLP]) and mast cell mediators (prostaglandin D 2 [PGD 2 ]) are critical activators of ILC2s. Cysteinyl leukotrienes (cysLTs), including leukotriene (LT) C 4 , LTD 4 , and LTE 4 , are metabolites of arachidonic acid and mediate inflammatory responses. Their role in human ILC2s is still poorly understood. We sought to determine the role of cysLTs and their relationship with other ILC2 stimulators in the activation of human ILC2s. For ex vivo studies, fresh blood from patients with atopic dermatitis and healthy control subjects was analyzed with flow cytometry. For in vitro studies, ILC2s were isolated and cultured. The effects of cysLTs, PGD 2 , IL-33, IL-25, TSLP, and IL-2 alone or in combination on ILC2s were defined by using chemotaxis, apoptosis, ELISA, Luminex, quantitative RT-PCR, and flow cytometric assays. The effect of endogenous cysLTs was assessed by using human mast cell supernatants. Human ILC2s expressed the LT receptor CysLT 1 , levels of which were increased in atopic subjects. CysLTs, particularly LTE 4 , induced migration, reduced apoptosis, and promoted cytokine production in human ILC2s in vitro. LTE 4 enhanced the effect of PGD 2 , IL-25, IL-33, and TSLP, resulting in increased production of type 2 and other proinflammatory cytokines. The effect of LTE 4 was inhibited by montelukast, a CysLT 1 antagonist. Interestingly, addition of IL-2 to LTE 4 and epithelial cytokines significantly amplified ILC2 activation and upregulated expression of the receptors for IL-33 and IL-25. CysLTs, particularly LTE 4 , are important contributors to the triggering of human ILC2s in inflammatory responses, particularly when combined with other ILC2 activators. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  14. Combustion of Na2B4O7 + Mg + C to synthesis B4C powders

    International Nuclear Information System (INIS)

    Jiang Guojian; Xu Jiayue; Zhuang Hanrui; Li Wenlan

    2009-01-01

    Boron carbide powder was fabricated by combustion synthesis (CS) method directly from mixed powders of borax (Na 2 B 4 O 7 ), magnesium (Mg) and carbon. The adiabatic temperature of the combustion reaction of Na 2 B 4 O 7 + 6 Mg + C was calculated. The control of the reactions was achieved by selecting reactant composition, relative density of powder compact and gas pressure in CS reactor. The effects of these different influential factors on the composition and morphologies of combustion products were investigated. The results show that, it is advantageous for more Mg/Na 2 B 4 O 7 than stoichiometric ratio in Na 2 B 4 O 7 + Mg + C system and high atmosphere pressure in the CS reactor to increase the conversion degree of reactants to end product. The final product with the minimal impurities' content could be fabricated at appropriate relative density of powder compact. At last, boron carbide without impurities could be obtained after the acid enrichment and distilled water washing.

  15. Simultaneous initiation of degranulation and inhibition of leukotriene release by soman in human basophils

    Energy Technology Data Exchange (ETDEWEB)

    Meier, H.L.; Warner, J.; MacGlashan, D.W.

    1995-12-31

    Previous studies noted that the serine esterase inhibitor, soman, could induce histamine release from human basophils. To investigate the mechanisms by which soman causes histamine release (a preformed mediator), we also examined its ability to induce leukotriene release (a newly synthesized mediator) from basophils. We found that no leukotriene release followed activation with soman, while histamine release was usually greater than 70%. In addition, soman and diisopropyl-fluorophosphate were found actively to suppress low level spontaneous leukotriene release as well as ongoing leukotriene release induced by anti-IgE antibody. Soman (0.3 mM) was able to stop leukotriene release as rapidly as the calcium chelator, EDTA. In a series of control experiments, it was noted that soman did not influence the metabolism of LTC4 to LTD4 or LTE4 (for which little metabolism occurred), eliminating the possibility that reduced LTC4 release could have resulted from its enhanced metabolism. Therefore, using one compound (soman), basophils could be simultaneously activated to degranulate while having the pathway leading to leukotriene release actively suppressed. These results provide further evidence that histamine and leukotriene release are independent pathways resulting from the activation of basophils.

  16. Trigon Farming ostis Kaiu LT / Margus Mikomägi

    Index Scriptorium Estoniae

    Mikomägi, Margus, 1956-

    2006-01-01

    Raplamaalt suuruselt neljas põllumajandusühistu Kaiu LT müüdi üldkoosoleku otsusega ühel häälel firmale Trigon Farming. Kaiu LT nõukogu esimees on viimased kolm aastat olnud Riigikogu liige Tiit Tammsaar. Lisa: Trigon Tarming investeerib põllumajandusse

  17. Introducing Leo LT - the "three-headed lion"

    Index Scriptorium Estoniae

    2008-01-01

    Leedu valitsus kiitis heaks seaduseparandused, mille tulemusena saab võtta tuumajaama ehitaja, investeerimis- ja energiafirma Leo LT strateegilise tähtsusega firmade hulka. Kui parlament valitsuse ettepanekud heaks kiidab, saab riik 61,7% Leo LT ja 38,3% NDX Energija aktsiatest

  18. Susceptibility to endotoxin induced uveitis is not reduced in mice deficient in BLT1, the high affinity leukotriene B4 receptor

    OpenAIRE

    Smith, J R; Subbarao, K; Franc, D T; Haribabu, B; Rosenbaum, J T

    2004-01-01

    Aim: To investigate the role of arachidonic acid derived chemotactic factor, LTB4, in the development of endotoxin induced uveitis (EIU), using mice deficient in the BLT1 gene which encodes the high affinity LTB4 receptor.

  19. Bronislaw Malinowski’nin Kültür Teorisi

    OpenAIRE

    Aman, Fatih

    2014-01-01

    Bir toplumu anlamak o toplumun kültürünü anlamaya bağlıdır. Özellikle “her toplumun kendine özgü olduğu” gerçeği kültür konusunda birçok araştırmanın yapılmasını sağlamış ve kültürel araştırmaları daha da ilginç kılmıştır. Bu araştırmalardan birisi de Bronislaw Malinowski’ye aittir. O, kültürün kökeniyle ilgilenmiş, kültürün fonksiyonlarını tanımlamış, kültürel araştırma tekniklerini ilk defa bilimsel ölçütlerle ortaya koymuş ve eleştirileriyle toplamda bir kültür teorisi oluşturmuştur. Malin...

  20. Leukotriene C4 synthase and ischemic cardiovascular disease and obstructive pulmonary disease in 13,000 individuals

    DEFF Research Database (Denmark)

    Freiberg, Jacob J; Dahl, Morten; Tybjaerg-Hansen, Anne

    2009-01-01

    Ischemic cardiovascular disease and obstructive pulmonary disease involve inflammation. Leukotrienes may be important pro-inflammatory mediators. We tested the hypothesis that the (-1072)G > A and (-444)A > C promoter polymorphisms of leukotriene C4 synthase confer risk of transient ischemic atta...... with risk of asthma or COPD. Leukotriene C4 synthase promoter genotypes influence risk of TIA and ischemic stroke, but not risk of IHD/coronary atherosclerosis, asthma, or COPD....

  1. 75 FR 27956 - Airworthiness Directives; Airbus Model A300 B4-600, B4-600R, and F4-600R Series Airplanes, and...

    Science.gov (United States)

    2010-05-19

    ... B4-600, B4-600R, and F4-600R Series Airplanes, and Model C4-605R Variant F Airplanes (Collectively...-203, and B4-203 airplanes; Model A300 B4-601, B4- 603, B4-620, B4-622, B4-605R, B4-622R, F4-605R, F4...

  2. 26 CFR 1.50B-4 - Partnerships.

    Science.gov (United States)

    2010-04-01

    ... § 1.50A-3, or if the partnership fails to pay comparable wages and such failure is subject to the... 26 Internal Revenue 1 2010-04-01 2010-04-01 true Partnerships. 1.50B-4 Section 1.50B-4 Internal... Credit for Expenses of Work Incentive Programs § 1.50B-4 Partnerships. (a) General rule—(1) In general...

  3. EphB4 as a therapeutic target in mesothelioma

    International Nuclear Information System (INIS)

    Liu, Ren; Ferguson, Benjamin D; Zhou, Yue; Naga, Kranthi; Salgia, Ravi; Gill, Parkash S; Krasnoperov, Valery

    2013-01-01

    Malignant pleural mesothelioma (MPM) often develops decades following exposure to asbestos. Current best therapy produces a response in only half of patients, and the median survival with this therapy remains under a year. A search for novel targets and therapeutics is underway, and recently identified targets include VEGF, Notch, and EphB4-Ephrin-B2. Each of these targets has dual activity, promoting tumor cell growth as well as tumor angiogenesis. We investigated EphB4 expression in 39 human mesothelioma tissues by immunohistochemistry. Xenograft tumors established with human mesothelioma cells were treated with an EphB4 inhibitor (monomeric soluble EphB4 fused to human serum albumin, or sEphB4-HSA). The combinatorial effect of sEphB4-HSA and biologic agent was also studied. EphB4 was overexpressed in 72% of mesothelioma tissues evaluated, with 85% of epithelioid and 38% of sarcomatoid subtypes demonstrating overexpression. The EphB4 inhibitor sEphB4-HSA was highly active as a single agent to inhibit tumor growth, accompanied by tumor cell apoptosis and inhibition of PI3K and Src signaling. Combination of sEphB4-HSA and the anti-VEGF antibody (Bevacizumab) was superior to each agent alone and led to complete tumor regression. EphB4 is a potential therapeutic target in mesothelioma. Clinical investigation of sEphB4-HSA as a single agent and in combination with VEGF inhibitors is warranted

  4. Design and Analysis of LT Codes with Decreasing Ripple Size

    DEFF Research Database (Denmark)

    Sørensen, Jesper Hemming; Popovski, Petar; Østergaard, Jan

    2012-01-01

    In this paper we propose a new design of LT codes, which decreases the amount of necessary overhead in comparison to existing designs. The design focuses on a parameter of the LT decoding process called the ripple size. This parameter was also a key element in the design proposed in the original...... work by Luby. Specifically, Luby argued that an LT code should provide a constant ripple size during decoding. In this work we show that the ripple size should decrease during decoding, in order to reduce the necessary overhead. Initially we motivate this claim by analytical results related...... to the redundancy within an LT code. We then propose a new design procedure, which can provide any desired achievable decreasing ripple size. The new design procedure is evaluated and compared to the current state of the art through simulations. This reveals a significant increase in performance with respect...

  5. Side Effects of Leukotriene Receptor Antagonists in Asthmatic Children.

    Science.gov (United States)

    Erdem, Semiha Bahceci; Nacaroglu, Hikmet Tekin; Unsal Karkiner, Canan Sule; Gunay, Ilker; Can, Demet

    2015-10-01

    Leukotriene receptor antagonists (LTRAs) are drugs which have been widely used more than ten years. As the use of LTRAs increases, our knowledge with respect to their side effects increases as well. The objective of our study was to evaluat the observed side effects of LTRAs used in patients with astma. 1024 patients treated only with LTRAs owing to asthma or early wheezing were included in the study for a five-year period. The observed side effects of LTRAs in these patients were retrospectively investigated. The side effects were divided into two parts as psychiatric and non-psychiatric. Among the 1024 cases included in the study, 67.5% of the patients out of 41 with side effects were male, 32.5% were female and the average age was 6.5 years. The rate of patients with asthma was 63.41% and 36.58% of the patients had early wheezing. It was determined that sex, age and diagnosis (early wheezing or asthma) of the patients were ineffective in the emergence of side effects. The average period for the emergence of side effects was the first month. It was observed that hyperactivity was the most frequently observed psychiatric side effect and that abdominal pain was the non-psychiatric side effect. The side effects of LTRAs were common in children. Therefore, patients must be informed at the beginning of the treatment and they must be evaluated at certain intervals.

  6. Urinary leukotriene E4 at 12 months and influencing factors

    Directory of Open Access Journals (Sweden)

    K Stencel-Gabriel

    2016-01-01

    • 3.        Department of Gynecology, Obstetrics and Oncological Gynecology, Bytom, Medical University of Silesia       Corresponding author: Krystyna Stencel-Gabriel ul. Batorego 15 41-902 Bytom   Keywords: leukotriene E4, infants, allergy, urine.   Summary Objective LTE4 is the end point of cysLTs pathway and its only stable product. Its role was discussed in asthma and AEDS. We aimed to investigate the impact of genetic and environmental factors ( sex, maternal positive family atopy history, breastfeeding, passive smoking and pet exposure . 60 newborns ( including 30 boys were enrolled in the study. Each child was examined at 12 months and urine samples for urinary LTE4 measurement were collected. All samples were processed using ACETM Enzyme Immunoassay Kit ( Cayman Chemical, Ann Arbor, MI, USA . The mean level of urinary LTE4 at 12 months was 186,99 pg/ml ( median: 159,0; CI 95%: 157,79- 221,59 . The Shapiro- Wilk test showed that the distribution of the levels of urinary LTE4 were abnormal. 12- month- old girls had higher urinary LTE4 levels than boys ( mean: 270,50 vs. 193,55 , but maternal positive atopy history, pet exposure, tobacco smoking or length of breastfeeding had no impact on urinary LTE4 excretion. Conclusions In conclusion, most of genetic or environmental factors do not change levels of urinary LTE4 in infants.

  7. 32 CFR 806b.4 - Privacy Act complaints.

    Science.gov (United States)

    2010-07-01

    ... be identified, the local Privacy Act officer will assume these duties. Issues that cannot be resolved... 32 National Defense 6 2010-07-01 2010-07-01 false Privacy Act complaints. 806b.4 Section 806b.4 National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE ADMINISTRATION PRIVACY ACT...

  8. 76 FR 27242 - Airworthiness Directives; Airbus Model A300 B4-600, B4-600R, and F4-600R Series Airplanes, and...

    Science.gov (United States)

    2011-05-11

    ... Airworthiness Directives; Airbus Model A300 B4-600, B4-600R, and F4-600R Series Airplanes, and Model C4-605R... applies to all Airbus Model A300 B4-601, B4-603, B4- 620, B4-622, B4-605R, B4-622R, F4-605R, F4-622R, and...

  9. 76 FR 59008 - Airworthiness Directives; Airbus Model A300 B4-600, B4-600R, and F4-600R Series Airplanes, and...

    Science.gov (United States)

    2011-09-23

    ... Airworthiness Directives; Airbus Model A300 B4-600, B4-600R, and F4-600R Series Airplanes, and Model C4-605R... to Airbus Model A300 B4-601, B4-603, B4-620, B4-622, B4-605R, B4-622R, F4-605R, F4-622R, and C4-605R...

  10. Molecular mechanisms of the synergy between cysteinyl-leukotrienes and receptor tyrosine kinase growth factors on human bronchial fibroblast proliferation

    Directory of Open Access Journals (Sweden)

    Hajime Yoshisue

    2006-12-01

    Full Text Available We have reported that cysteinyl-leukotrienes (cys-LTs synergise not only with epidermal growth factor (EGF but also with platelet-derived growth factor (PDGF and fibroblast growth factor (FGF to induce mitogenesis in human bronchial fibroblasts. We now describe the molecular mechanisms underlying this synergism. Mitogenesis was assessed by incorporation of [3H]thymidine into DNA and changes in protein phosphorylation by Western blotting. Surprisingly, no CysLT receptor antagonists (MK-571, montelukast, BAY u9773 prevented the synergistic mitogenesis. LTD4 did not cause phosphorylation of EGFR nor did it augment EGF-induced phosphorylation of EGFR, and the synergy between LTD4 and EGF was not blocked by the metalloproteinase inhibitor GM6001 or by an HB-EGF neutralising antibody. The EGFR-selective kinase inhibitor, AG1478, suppressed the synergy by LTD4 and EGF, but had no effect on the synergy with PDGF and FGF. While inhibitors of mitogen-activated protein kinase, phosphatidylinositol 3-kinase and protein kinase C (PKC prevented the synergy, these drugs also inhibited mitogenesis elicited by EGF alone. In contrast, pertussis toxin (PTX efficiently inhibited the potentiating effect of LTD4 on EGF-induced mitogenesis, as well as that provoked by PDGF or FGF, but had no effect on mitogenesis elicited by the growth factors alone. Whereas LTD4 alone did not augment phosphorylation of extracellular signal-regulated kinase (Erk-1/2 and Akt, it increased phosphorylation of PKC in a Gi-dependent manner. Addition of LTD4 prolonged the duration of EGF-induced phosphorylation of Erk-1/2 and Akt, both of which were sensitive to PTX. The effect of cys-LTs involves a PTX-sensitive and PKC-mediated intracellular pathway leading to sustained growth factor-dependent phosphorylation of Erk-1/2 and Akt.

  11. Effects of acrolein on leukotriene biosynthesis in human neutrophils.

    Science.gov (United States)

    Berry, Karin A Zemski; Henson, Peter M; Murphy, Robert C

    2008-12-01

    Acrolein is a toxic, highly reactive alpha,beta-unsaturated aldehyde that is present in high concentrations in cigarette smoke. In the current study, the effect of acrolein on eicosanoid synthesis in stimulated human neutrophils was examined. Eicosanoid synthesis in neutrophils was initiated by priming with granulocyte-macrophage colony-stimulating factor (GM-CSF) and subsequent stimulation with formyl-methionyl-leucyl-phenylalanine (fMLP) and 5-lipoxygenase (5-LO) products in addition to small amounts of cyclooxygenase (COX) products were detected using LC/MS/MS. A dose-dependent decrease in the formation of 5-LO products was observed in GM-CSF/fMLP-stimulated neutrophils when acrolein (0-50 microM) was present with almost complete inhibition at > or = 25 microM acrolein. The production of COX products was not affected by acrolein in these cells. The effect of acrolein was examined on key parts of the eicosanoid pathway, such as arachidonic acid release, intracellular calcium ion concentration, and adenosine production. In addition, the direct effect of acrolein on 5-LO enzymatic activity was probed using a recombinant enzyme. Some of these factors were affected by acrolein but did not completely explain the almost complete inhibition of 5-LO product formation in GM-CSF/fMLP-treated cells with acrolein. In addition, the effect of acrolein on different stimuli that initiate the 5-LO pathway [platelet-activating factor (PAF)/fMLP, GM-CSF/PAF, opsonized zymosan, and A23187] was examined. Acrolein had no significant effect on the leukotriene production in neutrophils stimulated with PAF/fMLP, GM-CSF/ PAF, or OPZ. Additionally, 50% inhibition of the 5-LO pathway was observed in A23187-stimulated neutrophils. Our results suggest that acrolein has a profound effect on the 5-LO pathway in neutrophils, which may have implications in disease states, such as chronic obstructive pulmonary disease and other pulmonary disease, where both activated neutrophils and acrolein are

  12. CysLT1 receptor-induced human airway smooth muscle cells proliferation requires ROS generation, EGF receptor transactivation and ERK1/2 phosphorylation

    Directory of Open Access Journals (Sweden)

    Capra Valérie

    2006-03-01

    Full Text Available Abstract Background Cysteine-containing leukotrienes (cysteinyl-LTs are pivotal inflammatory mediators that play important roles in the pathophysiology of asthma, allergic rhinitis, and other inflammatory conditions. In particular, cysteinyl-LTs exert a variety of effects with relevance to the aetiology of asthma such as smooth muscle contraction, eosinophil recruitment, increased microvascular permeability, enhanced mucus secretion and decreased mucus transport and, finally, airway smooth muscle cells (ASMC proliferation. We used human ASMC (HASMC to identify the signal transduction pathway(s of the leukotriene D4 (LTD4-induced DNA synthesis. Methods Proliferation of primary HASMC was measured by [3H]thymidine incorporation. Phosphorylation of EGF receptor (EGF-R and ERK1/2 was assessed with a polyclonal anti-EGF-R or anti-phosphoERKl/2 monoclonal antibody. A Ras pull-down assay kit was used to evaluate Ras activation. The production of reactive oxygen species (ROS was estimated by measuring dichlorodihydrofluorescein (DCF oxidation. Results We demonstrate that in HASMC LTD4-stimulated thymidine incorporation and potentiation of EGF-induced mitogenic signaling mostly depends upon EGF-R transactivation through the stimulation of CysLT1-R. Accordingly, we found that LTD4 stimulation was able to trigger the increase of Ras-GTP and, in turn, to activate ERK1/2. We show here that EGF-R transactivation was sensitive to pertussis toxin (PTX and phosphoinositide 3-kinase (PI3K inhibitors and that it occurred independently from Src activity, despite the observation of a strong impairment of LTD4-induced DNA synthesis following Src inhibition. More interestingly, CysLT1-R stimulation increased the production of ROS and N-acetylcysteine (NAC abolished LTD4-induced EGF-R phosphorylation and thymidine incorporation. Conclusion Collectively, our data demonstrate that in HASMC LTD4 stimulation of a Gi/o coupled CysLT1-R triggers the transactivation of the EGF

  13. 75 FR 60611 - Airworthiness Directives; Airbus Model A300 B4-600, B4-600R, and F4-600R Series Airplanes, and...

    Science.gov (United States)

    2010-10-01

    ... Airworthiness Directives; Airbus Model A300 B4-600, B4-600R, and F4-600R Series Airplanes, and Model A300 C4...; Model A300 B4-601, B4- 603, B4-620, B4-622, B4-605R, B4-622R, F4-605R, F4-622R, and C4-605R Variant F...-- Dated-- A300 series airplanes......... A300-32A0447..... April 22, 2004. A300 B4-600, B4-600R, and F4...

  14. Mastering Autodesk Inventor 2015 and Autodesk Inventor LT 2015

    CERN Document Server

    Waguespack, Curtis

    2014-01-01

    A comprehensive guide to Autodesk Inventor and Inventor LT This detailed reference and tutorial provides straightforward explanations, real-world examples, and practical tutorials that focus squarely on teaching Autodesk Inventor tips, tricks, and techniques. The book also includes a project at the beginning to help those new to Inventor quickly understand key interface conventions and capabilities. In addition, there is more information on Inventor LT, new practice drawings at the end of each chapter to reinforce lessons learned, and thorough coverage of all of Inventor's new features. The au

  15. 17 CFR 260.11b-4 - Definition of “cash transaction” in section 311(b)(4).

    Science.gov (United States)

    2010-04-01

    ... transaction”, as used in section 311(b)(4), means any transaction in which full payment for goods or securities sold is made within 7 days after delivery of the goods or securities in currency or in checks or...

  16. 75 FR 28480 - Airworthiness Directives; Airbus Model A300 Series Airplanes; Model A300 B4-600, B4-600R, F4-600R...

    Science.gov (United States)

    2010-05-21

    ... Airworthiness Directives; Airbus Model A300 Series Airplanes; Model A300 B4-600, B4-600R, F4-600R Series..., B4-622, B4- 605R, B4-622R, F4-605R, F4-622R, and C4-605R Variant F airplanes; and Model A310-203...

  17. Impact of botanical oils on polyunsaturated fatty acid metabolism and leukotriene generation in mild asthmatics

    Science.gov (United States)

    2013-01-01

    Background Dietary supplementation with botanical oils that contain n-6 and n-3 eighteen carbon chain (18C)-PUFA such as γ linolenic acid (GLA, 18:3n-6), stearidonic acid (SDA, 18:4n-3) and α linolenic acid (ALA, 18:3n-3) have been shown to impact PUFA metabolism, alter inflammatory processes including arachidonic acid (AA) metabolism and improve inflammatory disorders. Methods The diet of mild asthmatics patients was supplemented for three weeks with varying doses of two botanical seed oils (borage oil [Borago officinalis, BO] and echium seed oil [Echium plantagineum; EO]) that contain SDA, ALA and GLA. A three week wash out period followed. The impact of these dietary manipulations was evaluated for several biochemical endpoints, including in vivo PUFA metabolism and ex vivo leukotriene generation from stimulated leukocytes. Results Supplementation with several EO/BO combinations increased circulating 20–22 carbon (20–22C) PUFAs, including eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA), and dihommo-gammalinolenic acid (DGLA), which have been shown to inhibit AA metabolism and inflammation without impacting circulating AA levels. BO/EO combinations also inhibited ex vivo leukotriene generation with some combinations attenuating cysteinyl leukotriene generation in stimulated basophils by >50% and in stimulated neutrophils by >35%. Conclusions This study shows that dietary supplementation with BO/EO alters 20–22C PUFA levels and attenuates leukotriene production in a manner consistent with a reduction in inflammation. PMID:24088297

  18. Exhaled Leukotrienes and Bronchial Responsiveness to Methacholine in Patients with Seasonal Allergic Rhinitis

    Czech Academy of Sciences Publication Activity Database

    Čáp, P.; Malý, Marek; Pehal, F.; Pelikán, Z.

    2009-01-01

    Roč. 102, č. 2 (2009), s. 103-109 ISSN 1081-1206 Grant - others:GA MZd(CZ) NL7024 Institutional research plan: CEZ:AV0Z10300504 Keywords : allergic rhinitis * asthma * breath condensate * leukotrienes * gas chromatography * mass spectrometry analysis Subject RIV: FN - Epidemiology, Contagious Diseases ; Clinical Immunology Impact factor: 2.457, year: 2009

  19. Analysis of Exhaled Leukotrienes in Nonasthmatic Adult Patients with Seasonal Allergic Rhinitis

    Czech Academy of Sciences Publication Activity Database

    Čáp, P.; Pehal, F.; Malý, Marek; Chládek, J.

    2005-01-01

    Roč. 60, č. 2 (2005), s. 171-176 ISSN 0105-4538 Source of funding: V - iné verejné zdroje Keywords : allergic rhinitis * asthma * breath condensate * gas-chromatography/mass spectrometry analysis * leukotrienes Subject RIV: BB - Applied Statistics, Operational Research Impact factor: 4.120, year: 2005

  20. Leukotrienes and 8-isoprostane in exhaled breath condensate in bronchoprovocation tests with occupational allergens

    Czech Academy of Sciences Publication Activity Database

    Klusáčková, P.; Lebedová, J.; Kačer, P.; Kuzma, Marek; Brabec, Marek; Pelclová, D.; Fenclová, Z.; Navrátil, Tomáš

    2008-01-01

    Roč. 78, 4-5 (2008), s. 281-292 ISSN 0952-3278 Institutional research plan: CEZ:AV0Z50200510; CEZ:AV0Z10300504; CEZ:AV0Z40400503 Keywords : occupational allergens * leukotrienes * 8-isoprostane Subject RIV: CC - Organic Chemistry Impact factor: 1.366, year: 2008

  1. Gas Chromatography/mass Spectrometry Analysis of Exhaled Leukotrienes in Asthmatic Patients

    Czech Academy of Sciences Publication Activity Database

    Čáp, P.; Chládek, J.; Pehal, F.; Malý, Marek; Petrů, V.; Barnes, P.J.; Montuschi, P.

    2004-01-01

    Roč. 59, č. 6 (2004), s. 465-470 ISSN 0040-6376 Source of funding: V - iné verejné zdroje Keywords : asthma * breath condensate * gas chromatography/mass spectrometry * leukotrienes Subject RIV: BB - Applied Statistics, Operational Research Impact factor: 5.040, year: 2004

  2. Staphylococcus aureus and influenza A virus stimulate human bronchoalveolar cells to release histamine and leukotrienes

    DEFF Research Database (Denmark)

    Clementsen, P; Bisgaard, H; Pedersen, M

    1989-01-01

    persons were stimulated with Staph. aureus no release of leukotriene C4 was found. The mediator release caused by bacteria and virus might be of importance for the exacerbation of bronchial asthma in upper respiratory tract infections, since histamine is assumed to increase the epithelial permeability...

  3. Leukotriene-mediated neuroinflammation, toxic brain damage, and neurodegeneration in acute methanol poisoning

    Czech Academy of Sciences Publication Activity Database

    Zakharov, S.; Kotíková, K.; Nurieva, O.; Hlušička, J.; Kačer, P.; Urban, P.; Vaněčková, M.; Seidl, Z.; Diblík, P.; Kuthan, P.; Navrátil, Tomáš; Pelclová, D.

    2017-01-01

    Roč. 55, č. 4 (2017), s. 249-259 ISSN 1556-3650 Institutional support: RVO:61388955 Keywords : brain damage * leukotrienes * methanol poisoning * Neuroinflammation * nontraumatic brain injury * sequelae of poisoning Subject RIV: CG - Electrochemistry OBOR OECD: Electrochemistry (dry cells, batteries, fuel cells, corrosion metals, electrolysis) Impact factor: 3.677, year: 2016

  4. 8-Isoprostane and leukotrienes in exhaled breath condensate in czech subjects with silicosis

    Czech Academy of Sciences Publication Activity Database

    Pelclová, D.; Fenclová, Z.; Kačer, P.; Navrátil, Tomáš; Kuzma, Marek; Lebedová, J.; Klusáčková, P.

    2007-01-01

    Roč. 45, č. 6 (2007), s. 766-774 ISSN 0019-8366 Grant - others:GA MZd NR8107 Institutional research plan: CEZ:AV0Z40400503; CEZ:AV0Z50200510 Keywords : silica * silicosis * 8-isoprostane * leukotrienes Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 0.792, year: 2007

  5. LT COL F.F. PIENAAR'S BOER WAR DIARY

    African Journals Online (AJOL)

    LT COL F.F. PIENAAR'S BOER WAR DIARY. (PART II). Brig J.H. Picard, SM*. FREE STATE TO ..... bing up and down on his master's spare horse. ... Jantjie and his master turned out of the road, and ..... on a list which burghers could afford to.

  6. Potential probiotic of Lactobacillus johnsonii LT171 for chicken ...

    African Journals Online (AJOL)

    The objective of this research was to investigate the potential probiotic of Lactobacillus johnsonii LT171. It had aggregation (60 min) and antibacterial effects against Salmonella Enteritidis, Salmonella Typhimurium and Escherichia coli O78:K80. It showed amylase and protease activity and high clear zone in culture medium ...

  7. Ripple design of LT codes for AWGN channel

    DEFF Research Database (Denmark)

    Sørensen, Jesper Hemming; Koike-Akino, Toshiaki; Orlik, Philip

    2012-01-01

    In this paper, we present an analytical framework for designing LT codes in additive white Gaussian noise (AWGN) channels. We show that some of analytical results from binary erasure channels (BEC) also hold in AWGN channels with slight modifications. This enables us to apply a ripple-based design...

  8. Hot pressing of B4C/SiC composites

    International Nuclear Information System (INIS)

    Sahin, F.C.; Turhan, E.; Yesilcubuk, S.A.; Addemir, O.

    2005-01-01

    B 4 C/SiC ceramic composites containing 10-20-30 vol % SiC were prepared by hot pressing method. The effect of SiC addition and hot pressing temperature on sintering behaviour and mechanical properties of hot pressed composites were investigated. Microstructures of hot pressed samples were examined by SEM technique. Three different temperatures (2100 deg. C, 2200 deg. C and 2250 deg. C) were used to optimize hot pressing temperature applying 100 MPa pressure under argon atmosphere during the sintering procedure. The highest relative density of 98.44 % was obtained by hot pressing at 2250 deg. C. However, bending strengths of B 4 C/SiC composite samples were lower than monolithic B 4 C in all experimental conditions. (authors)

  9. 2012 ETA Guidelines: The Use of L-T4 + L-T3 in the Treatment of Hypothyroidism

    DEFF Research Database (Denmark)

    Nygaard, Birte

    2012-01-01

    . Results: Suggested explanations for persisting symptoms include: awareness of a chronic disease, presence of associated autoimmune diseases, thyroid autoimmunity per se, and inadequacy of L-T4 treatment to restore physiological thyroxine (T4) and triiodothyronine (T3) concentrations in serum and tissues...

  10. The anti-inflammatory effect of montelukast, a cysteinyl leukotriene receptor-1 antagonist, against estradiol-induced nonbacterial inflammation in the rat prostate.

    Science.gov (United States)

    Said, Mahmoud M; Bosland, Maarten C

    2017-02-01

    There is no standard treatment of chronic nonbacterial prostatitis in humans. The current study was aimed to investigate the effect of montelukast, an antagonist of cysteinyl leukotriene receptor-1, against estrogen-induced, nonbacterial lateral lobe-specific prostate inflammation in rats. Male Wistar rats were randomized into five groups of six rats, including sham controls (group 1) and castrated rats (group 2), whereas nonbacterial prostatitis (NBP) was induced in groups 3-5 by castration followed by a daily subcutaneous injection of estradiol (0.25 mg/kg body weight) for 30 days. The rats were left otherwise untreated (group 3) or received a daily oral administration of montelukast (1 and 10 mg/kg body weight for groups 4 and 5, respectively) from the 17th day after castration for two consecutive weeks. Compared with sham controls, induction of NBP led to a significant increase in serum leukotriene B 4 (LTB4), tumor necrosis factor alpha (TNF-α), and interleukin 6 (IL-6) levels, along with a significant upregulation in the transcript level of proinflammatory molecules (nuclear factor kappa beta [NF-κβ] and inducible nitric oxide synthase [iNOS]), chemokines (monocyte chemoattractant protein-1 [MCP-1] and eotaxin), and E-selectin in the lateral prostate. Histological examination revealed intense inflammation in the prostate with leukocyte infiltration and acinar degeneration following estradiol treatment of castrated rats. Montelukast significantly suppressed the increase in serum and prostate proinflammatory mediators/chemokines expression and abolished the histologically inflammatory changes in the lateral prostate. These findings indicate that montelukast inhibits estradiol-induced NBP in a rat model through anti-inflammatory mechanisms, suggesting its future beneficial effect for the treatment of clinical chronic NBP.

  11. 76 FR 38069 - Airworthiness Directives; Airbus Model A300 B4-600, B4-600R, and F4-600R Series Airplanes, and...

    Science.gov (United States)

    2011-06-29

    ... B4-600, B4-600R, and F4-600R Series Airplanes, and Model C4-605R Variant F Airplanes (Collectively...-603, B4-620, B4-622, B4-605R, B4-622R, F4-605R, F4-622R, and C4-605R Variant F airplanes; and Model...

  12. 12 CFR 264b.4 - Gifts of minimal value.

    Science.gov (United States)

    2010-01-01

    ... RULES REGARDING FOREIGN GIFTS AND DECORATIONS § 264b.4 Gifts of minimal value. (a) Board employees may... occur on the same day. (b) Board employees may determine at the time a gift is offered whether it is of... for valuation. (c) Disagreements over whether a gift is of minimal value will be resolved by an...

  13. 26 CFR 1.410(b)-4 - Nondiscriminatory classification test.

    Science.gov (United States)

    2010-04-01

    ..., nature of compensation (i.e., salaried or hourly), geographic location, and similar bona fide business... (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES Pension, Profit-Sharing, Stock Bonus Plans, Etc. § 1.410(b)-4 Nondiscriminatory classification test. (a) In general. A plan satisfies the nondiscriminatory classification test of...

  14. Directional crystallization of B4C-NbB2 and B4C-MoB2 eutectic compositions

    International Nuclear Information System (INIS)

    Paderno, Varvara; Paderno, Y.B.; Filippov, Vladimir; Liashchenko, Alfred

    2004-01-01

    We studied the directional crystallization of different compositions in B 4 C-NbB 2 and B 4 C-MoB 2 systems. The eutectic compositions for both systems are evaluated. It is shown that in the first system the rod-like eutectic structure is formed, in second, the 'Chinese hieroglyphics'. In both cases high hardness and high microplasticity are observed, which are much more than for individual component phases. These compositions may be considered as a new kind of self-strengthening composite materials

  15. Containment pressure analysis model using CONTEMPT-LT

    International Nuclear Information System (INIS)

    Gupta, R.N.

    1975-09-01

    An analytical model for evaluating the reactor containment pressure transient following a loss-of-coolant accident (LOCA) is presented. The model uses the CONTEMPT-LT computer program developed by Aerojet Nuclear Company. The sample problem studied is the containment response following the most severe postulated LOCA at the Yankee Rowe Nuclear Power Station. The results show good agreement with the response predicted by Westinghouse Electric Corporation. (auth)

  16. Structural characterization of the Salmonella typhimurium LT2 umu operon

    International Nuclear Information System (INIS)

    Thomas, S.M.; Crowne, H.M.; Pidsley, S.C.; Sedgwick, S.G.

    1990-01-01

    The umuDC operon of Escherichia coli encodes functions required for mutagenesis induced by radiation and a wide variety of chemicals. The closely related organism Salmonella typhimurium is markedly less mutable than E. coli, but a umu homolog has recently been identified and cloned from the LT2 subline. In this study the nucleotide sequence and structure of the S. typhimurium LT2 umu operon have been determined and its gene products have been identified so that the molecular basis of umu activity might be understood more fully. S. typhimurium LT2 umu consists of a smaller 417-base-pair (bp) umuD gene ending 2 bp upstream of a larger 1,266-bp umuC gene. The only apparent structural difference between the two operons is the lack of gene overlap. An SOS box identical to that found in E. coli is present in the promoter region upstream of umuD. The calculated molecular masses of the umuD and umuC gene products were 15.3 and 47.8 kilodaltons, respectively, which agree with figures determined by transpositional disruption and maxicell analysis. The S. typhimurium and E. coli umuD sequences were 68% homologous and encoded products with 71% amino acid identity; the umuC sequences were 71% homologous and encoded products with 83% amino acid identity. Furthermore, the potential UmuD cleavage site and associated catalytic sites could be identified. Thus the very different mutagenic responses of S. typhimurium LT2 and E. coli cannot be accounted for by gross differences in operon structure or gene products. Rather, the ability of the cloned S. typhimurium umuD gene to give stronger complementation of E. coli umuD77 mutants in the absence of a functional umuC gene suggests that Salmonella UmuC protein normally constrains UmuD protein activity

  17. Kinetic studies on binding of thyroid hormones (L-T3 and L-T4) to the receptors of lymphocyte cells isolated from uraemia subjects

    International Nuclear Information System (INIS)

    Al-Sultani, A.S.J.

    1989-01-01

    The levels of L-T 3 , L-T 4 and TSH in uremic sera have been measured by (RIA), and shown to have a decrease in both L-T 3 and L-T 4 levels with normal level of TSH for most specimens used in this study. Kinetics properties for binding of thyroid hormones L-T 3 and L-T 4 with nuclear receptors of human lymphocyte cells extracted from uremic patient have been studied and compared this result with control and hypothyroidism subjects and we obtained that uremic condition have a large effect on these nuclear receptors properties. Dissociation constant (K d ) and maximal binding capacity (MBC) of both L-T 3 and L-T 4 with these nuclear receptors have been determined, and we obtained that uremic condition did not affect on (K d ) values for both L-T 3 and L-T 4 but it affected on (MBC) values compared with normal subject. 8 tabs.; 25 figs.; 203 refs

  18. Low temperature solid oxide electrolytes (LT-SOE): A review

    Science.gov (United States)

    Singh, B.; Ghosh, S.; Aich, S.; Roy, B.

    2017-01-01

    Low temperature solid oxide fuel cell (LT-SOFC) can be a source of power for vehicles, online grid, and at the same time reduce system cost, offer high reliability, and fast start-up. A huge amount of research work, as evident from the literature has been conducted for the enhancement of the ionic conductivity of LT electrolytes in the last few years. The basic conduction mechanisms, advantages and disadvantages of different LT oxide ion conducting electrolytes {BIMEVOX systems, bilayer systems including doped cerium oxide/stabilised bismuth oxide and YSZ/DCO}, mixed ion conducting electrolytes {doped cerium oxides/alkali metal carbonate composites}, and proton conducting electrolytes {doped and undoped BaCeO3, BaZrO3, etc.} are discussed here based on the recent research articles. Effect of various material aspects (composition, doping, layer thickness, etc.), fabrication methods (to achieve different microstructures and particle size), design related strategies (interlayer, sintering aid etc.), characterization temperature & environment on the conductivity of the electrolytes and performance of the fuel cells made from these electrolytes are shown in tabular form and discussed. The conductivity of the electrolytes and performance of the corresponding fuel cells are compared. Other applications of the electrolytes are mentioned. A few considerations regarding the future prospects are pointed.

  19. 76 FR 441 - Airworthiness Directives; Airbus Model A300 B4-600, B4-600R, and F4-600R Series Airplanes, and...

    Science.gov (United States)

    2011-01-05

    ... Airworthiness Directives; Airbus Model A300 B4-600, B4-600R, and F4-600R Series Airplanes, and Model C4-605R...-622, B4-605R, B4-622R, F4-605R, F4-622R, and C4-605R Variant F airplanes, certificated in any category...

  20. 76 FR 28914 - Airworthiness Directives; Airbus Model A300 B4-600, B4-600R, and F4-600R Series Airplanes, and...

    Science.gov (United States)

    2011-05-19

    ... B4-600, B4-600R, and F4-600R Series Airplanes, and Model C4-605R Variant F Airplanes (Collectively... B4-605R and B4-622R airplanes; A300 F4-605R and F4-622R airplanes; A300 C4-605R Variant F airplanes...

  1. B4C control rod behavior during severe accident sequences

    International Nuclear Information System (INIS)

    Steinbrueck, M.

    2003-01-01

    The oxidation kinetics of various types of boron carbides (pellets, powder) as well as the degradation of B 4 C control rod segments were investigated in the temperature range between 800 and 1600 deg C. Mass spectrometric gas analysis was used to determine oxidation rates in transient and isothermal tests. The oxidation kinetics of boron carbide are determined by the formation of a liquid boron oxide layer and its loss due to the reaction with surplus steam to form volatile boric acids and at temperatures above 1500 deg C by direct evaporation. Under these test conditions linear oxidation kinetics are established soon after oxidation has initiated. The oxidation kinetics are strongly influenced by the thermal-hydraulic boundary conditions, in particular by the steam flow rate. Only very low amounts of methane were ever produced in these tests. Enhanced degradation of B 4 C control rods starts with the rapid formation of eutectic melts in the systems B 4 C-stainless steel (SS) and SS-Zircaloy at temperatures above 1250 deg C. Initially, this melt is kept within a ZrO 2 scale externally formed at the Zircaloy guide tube. The absorber melt is rapidly oxidized after failure of the oxide shell and aggressively attacks adjacent fuel claddings. (author)

  2. In vivo formation of beta-oxidized metabolites of leukotriene E4 in the rat

    International Nuclear Information System (INIS)

    Perrin, P.; Zirrolli, J.; Stene, D.O.; Lellouche, J.P.; Beaucourt, J.P.; Murphy, R.C.

    1989-01-01

    Intraperitoneal administration of [ 3 H]-leukotriene E4 in the rat resulted in the appearance of radiolabel in urine and feces. Separation of polar urinary metabolites and chromatographic comparison of synthetic metabolites indicated the in vivo formation of omega-oxidized metabolites of LTE4 with sequential beta-oxidation. Furthermore, the metabolite identified as 16-carboxy-17,18,19,20-tetranor-14,15-dihydro-N-acetyl-LTE4 substantiates the biochemical pathway of beta-oxidation in vivo involving the 2,4-dienoyl CoA reductase as an integral step. These results substantiate beta-oxidation of sulfidopeptide leukotrienes in vivo and these metabolites account for some of the major urinary metabolites of this class of lipid mediator

  3. Promotor polymorphisms in leukotriene C4 synthase and risk of ischemic cerebrovascular disease

    DEFF Research Database (Denmark)

    Freiberg, J.J.; Tybjaerg-Hansen, A.; Sillesen, H.

    2008-01-01

    OBJECTIVE: Cysteinyl leukotrienes are involved in inflammation and possibly in early carotid atherosclerosis. We tested the hypothesis that the -444 A/C and -1072 G/A polymorphisms of the leukotriene C(4) synthase associate with risk of ischemic cerebrovascular disease. METHODS AND RESULTS: We...... genotyped 10 592 individuals from the Danish general population, the Copenhagen City Heart Study. During 24 years of follow-up, 557 individuals developed ischemic cerebrovascular disease. The allele frequency was 0.07 for -1072 A and 0.29 for -444 C. Cumulative incidence for ischemic cerebrovascular disease...... was higher for -1072 AA versus GG genotype (log-rank: P=0.002), and lower for -444 CC versus AA genotype (log-rank: P=0.008). Combined genotypes showed corresponding cumulative incidence differences (log-rank: P=0.003). Multifactorially adjusted hazard ratios for ischemic cerebrovascular disease were 2...

  4. Blockade of leukotriene production by a single oral dose of MK-0591 in active ulcerative colitis

    DEFF Research Database (Denmark)

    Hillingsø, Jens; Kjeldsen, J; Laursen, L S

    1995-01-01

    dialysis fluid, ex vivo biosynthesis of LTB4 in whole blood, and urinary excretion of leukotriene E4 (LTE4) from 16 patients with mild to moderately active distally located ulcerative colitis were measured by use of radioimmunoassays in a double-blind, placebo-controlled parallel-design study before...... was unchanged. In whole blood, MK-0591 decreased ex vivo biosynthesis of LTB4 (p LTE4 was reduced by more than 85% (p

  5. Exercise-induced bronchoconstriction: The effects of montelukast, a leukotriene receptor antagonist

    Directory of Open Access Journals (Sweden)

    James P Kemp

    2009-11-01

    Full Text Available James P KempClinical Professor of Pediatrics, Division of Immunology and Allergy, University of California School of Medicine, San Diego, CA, USAAbstract: Exercise-induced bronchoconstriction (EIB is very common in both patients with asthma and those who are otherwise thought to be normal. The intensity of exercise as well as the type of exercise is important in producing symptoms. This may make some types of exercise such as swimming more suitable and extended running more difficult for patients with this condition. A better understanding of EIB will allow the physician to direct the patient towards a type of exercise and medications that can result in a more active lifestyle without the same concern for resulting symptoms. This is especially important for schoolchildren who are usually enrolled in physical education classes and elite athletes who may desire to participate in competitive sports. Fortunately several medications (short- and long-acting β2-agonists, cromolyn, nedocromil, inhaled corticosteroids, and more recently leukotriene modifiers have been shown to be effective in preventing or attenuating the effects of exercise in many patients. In addition, inhaled β2-agonists have been shown to quickly reverse the airway obstruction that develops in patients and continue to be the reliever medications of choice. Inhaled corticosteroids are increasingly being recommended as regular therapy now that the role of inflammation and airway injury has been identified in EIB. With the discovery that there is a release of mediators such as histamine and leukotrienes from cells in the airway following exercise with resulting airway obstruction in susceptible individuals, interest has turned to attenuating their effects with mediator antagonists especially those that block the effects of leukotrienes. Studies with an oral leukotriene antagonist, montelukast, have shown beneficial effects in adults and children aged as young as 6 years with EIB

  6. Magnetic anomaly in superconducting TmRh4B4

    International Nuclear Information System (INIS)

    Smith, J.L.; Huang, C.Y.; Tsou, J.J.; Ho, J.C.

    1978-01-01

    The magnetic and superconducting properties of TmRh 4 B 4 (which becomes superconducting at 9.6 K) by means of ac and dc magnetic susceptibility and specific heat measurements are investigated. At 10.7 K, an ac susceptibility peak similar to those found in spin glasses has been observed. In addition, a pronounced specific heat peak has been observed at 11.4 K. The susceptibility peak is essentially unaffected by substitution of 1% Lu or Er for the Tm, but it diminishes when much larger amounts of Er are substituted. The physical origin of this anomalous peak will be discussed

  7. Autodesk Inventor 2013 and Autodesk Inventor LT 2013 essentials

    CERN Document Server

    Tremblay, Thom

    2012-01-01

    Get up to speed with Autodesk Inventor, the leading manufacturing design program This Autodesk Official Training Guide thoroughly covers the fundamentals of Autodesk Inventor 2013 and Inventor LT 2013. Focusing on basics such as using the interface, creating parts and assemblies, applying standards and styles, creating 2D drawings from 3D data, and more, it teaches you everything you need to become quickly productive with the software. Whether you're a new student learning CAD, preparing for certification, or updating your Inventor skills, this is the fast, thorough grounding you need. Featu

  8. Variability of Two Young L/T Transition Brown Dwarfs

    Science.gov (United States)

    Allers, Katelyn; Biller, Beth; Gallimore, Jack; Crossfield, Ian

    2015-10-01

    We propose for photometric monitoring observations of WISEP J004701.06+680352 (hereinafter W0047) and 2MASSWJ2244316+204343 (hereinafter 2M2244) using Spitzer/IRAC. Both objects are kinematically confirmed L7 members of the 150 Myr old AB Doradus moving group and show remarkable spectral similarity in both the near-IR and optical. The WoW survey found that L/T transition brown dwarfs having detected mid-IR variability are redder than the typical J - K color for their spectral type. A Cycle 11 exploration program (P.I. Metchev) is investigating the geometrical dependence of color and variability by expanding the original WoW sample. If inclination and J - K color are correlated (as predicted by Metchev et al.), then the spectral and photometric diversity seen across the L/T transition could be explained by geometry rather than diversity in atmospheric chemistry and dynamics. This would have wide ranging implications for the way we model cloud dissipation for brown dwarfs and extrasolar planets. Our proposed observations will provide an important test of the Metchev et al. prediction complementary to their Cycle 11 program. W0047 and 2M2244 are the same age, and have remarkably similar colors (J - K = 2.55 and 2.46 mags, respectively) and underlying spectra. Thus, if Metchev's prediction about the correlation of inclination and spectral morphology holds true, we would expect that W0047 and 2M2244 should have similar inclinations. However, the measured v sin(i) values for W0047 and 2M2244 are quite different. This difference in v sin(i) could be due to spin-axis inclination (with W0047 having a smaller i) or orbital period (with W0047 having a longer period), both of which we will determine from our proposed observations. This test is a unique opportunity, as there are no other free-floating L/T transition dwarfs known to be both coeval and spectrally similar. Our proposed observations will also extend the spectral type range for young objects surveyed for variability

  9. Mastering Autodesk Inventor 2014 and Autodesk Inventor LT 2014

    CERN Document Server

    Waguespack, Curtis

    2013-01-01

    An Autodesk Official Press guide to the powerful mechanical design software Autodesk Inventor has been used to design everything from cars and airplanes to appliances and furniture. This comprehensive guide to Inventor and Inventor LT features real-world workflows and work environments, and is packed with practical tutorials that focus on teaching Inventor tips, tricks, and techniques. Additionally, you can download datasets to jump in and practice on any exercise. This reference and tutorial explains key interface conventions, capabilities, tools, and techniques, including desi

  10. Autodesk Inventor 2012 and Inventor LT 2012 Essentials

    CERN Document Server

    Tremblay, Thom

    2011-01-01

    Essential guide to learning Autodesk Inventor and Inventor LT The new Essentials books from Sybex are beautiful, task-based, full-color Autodesk Official Training Guides that help you get up to speed on Autodesk topics quickly and easily. Inventor Essentials thoroughly covers core features and functions of Autodesk's industry-leading 3D mechanical design software, teaching you what you need to become quickly productive with the software. By following the book's clear explanations, practical tutorials, and step-by-step exercises, you'll cover all the bases. Topics include drawing, modeling part

  11. AutoCAD / AutoCAD LT 2014 fundamentals metric

    CERN Document Server

    ASCENT center for technical knowledge

    2014-01-01

    The objective of AutoCAD/AutoCAD LT 2014 Fundamentals is to enable students to create a basic 2D drawing in the AutoCAD software. Even at this fundamental level, the AutoCAD software is one of the most sophisticated computer applications that you are likely to encounter. Therefore learning to use it can be challenging. To make the process easier and provide flexibility for instructors and students, the training guide is divided into two parts that can be taken independently.

  12. 75 FR 76926 - Airworthiness Directives; Airbus Model A300 B4-600, B4-600R, and F4-600R Series Airplanes, and...

    Science.gov (United States)

    2010-12-10

    ... Airworthiness Directives; Airbus Model A300 B4-600, B4-600R, and F4-600R Series Airplanes, and Model C4-605R... airplanes; Model A300 B4-605R and B4-622R airplanes; Model A300 F4-605R and F4-622R airplanes; Model A300 C4...

  13. 76 FR 42029 - Airworthiness Directives; Airbus Model A300 B4-600, B4-600R, and F4-600R Series Airplanes, and...

    Science.gov (United States)

    2011-07-18

    ... Airworthiness Directives; Airbus Model A300 B4-600, B4-600R, and F4-600R Series Airplanes, and Model A300 C4... A300 B4-605R and B4-622R airplanes, Model A300 F4-605R and F4-622R airplanes, and Model A300 C4- [[Page...

  14. 76 FR 18960 - Airworthiness Directives; Airbus Model A300 B4-600, B4-600R, and F4-600R Series Airplanes, and...

    Science.gov (United States)

    2011-04-06

    ... B4-600, B4-600R, and F4-600R Series Airplanes, and Model C4-605R Variant F Airplanes (Collectively... July 20, 2005; have been performed in service. (2) Airbus Model A300 B4-605R, B4-622R, F4-605R, and F4... C4-600R, and A300 F4-600R series airplanes (fitted with a trim tank), all serial numbers, except...

  15. 76 FR 39248 - Airworthiness Directives; Airbus Model A300 B4-600, B4-600R, and F4-600R Series Airplanes, and...

    Science.gov (United States)

    2011-07-06

    ... Airworthiness Directives; Airbus Model A300 B4-600, B4-600R, and F4-600R Series Airplanes, and Model C4-605R... B4-605R and B4-622R airplanes; Model A300 F4-605R and F4-622R airplanes; Model A300 C4-605R Variant F...

  16. Repeated allergen exposure reduce early phase airway response and leukotriene release despite upregulation of 5-lipoxygenase pathways

    Directory of Open Access Journals (Sweden)

    Cui Zhi-Hua

    2012-03-01

    Full Text Available Abstract Background Allergen induced early phase airway response and airway plasma exudation are predominantly mediated by inflammatory mast cell mediators including histamine, cysteinyl leukotrienes (cysLTs and thromboxane A2 (TXA2. The aim of the present study was to evaluate whether repeated allergen exposure affects early phase airway response to allergen challenge. Methods A trimellitic anhydride (TMA sensitized guinea pig model was used to investigate the effects of low dose repeated allergen exposure on cholinergic airway responsiveness, early phase airway response and plasma exudation, as well as local airway production of mast cell derived cysteinyl leukotrienes and thromboxane B2 (TXB2 after allergen challenge. Results Repeated low dose allergen exposure increased cholinergic airway responsiveness. In contrast, early phase airway response and plasma exudation in response to a high-dose allergen challenge were strongly attenuated after repeated low dose allergen exposure. Inhibition of the airway response was unspecific to exposed allergen and independent of histamine receptor blocking. Furthermore, a significant reduction of cysteinyl leukotrienes and TXB2 was found in the airways of animals repeatedly exposed to a low dose allergen. However, in vitro stimulation of airway tissue from animals repeatedly exposed to a low dose allergen with arachidonic acid and calcium ionophore (A23187 induced production of cysteinyl leukotrienes and TXB2, suggesting enhanced activity of 5-lipoxygenase and cyclooxygenase pathways. Conclusions The inhibition of the early phase airway response, cysteinyl leukotriene and TXB2 production after repeated allergen exposure may result from unresponsive effector cells.

  17. 76 FR 6581 - Airworthiness Directives; Airbus Model A300 B4-600, B4-600R, and F4-600R Series Airplanes, and...

    Science.gov (United States)

    2011-02-07

    ... B4-600, B4-600R, and F4-600R Series Airplanes, and Model C4-605R Variant F Airplanes (Collectively...-605R, B4-622R, F4-605R, F4-622R, and C4-605R Variant F airplanes, certificated in any category, all...

  18. The effect of the leukotriene antagonist pranlukast on pediatric acute otitis media.

    Science.gov (United States)

    Nakamura, Yoshihisa; Hamajima, Yuki; Suzuki, Motohiko; Esaki, Shinichi; Yokota, Makoto; Oshika, Masanori; Takagi, Ippei; Yasui, Keiko; Miyamoto, Naoya; Sugiyama, Kazuko; Nakayama, Meiho; Murakami, Shingo

    2016-08-01

    Conventional treatment for acute otitis media mainly targets bacteria with antibiotics, neglecting to control for mediators of inflammation. Mediators of inflammation, such as leukotrienes, have been identified in patients with acute otitis media (AOM) or subsequent secretory otitis media (SOM). They can cause functional eustachian tube dysfunction or increase mucous in the middle ear, causing persistent SOM following AOM. The objective of the present study was to evaluate whether or not administration of pranlukast, a widely used leukotriene C4, D4, and E4 antagonist, together with antibiotics could inhibit the progression to SOM. Children with AOM, who were from two to 12 years old, were randomly divided into two groups as follows: a control group in which 50 patients received antibiotic-based conventional treatment according to guidelines for treating AOM proposed by the Japan Otological Society (version 2006); and a pranlukast group, in which 52 patients were administered pranlukast for up to 28 days as well as given conventional treatment. Cases were regarded as persistent SOM when a tympanogram was type B or C2 four weeks after treatment was initiated. Two patients in the pranlukast group and 3 patients in the control group were excluded because they relapsed AOM within 28 days after initial treatment. Therefore, the analysis included 50 and 47 subjects in the pranlukast and control groups, respectively. The percentage of patients diagnosed with persistent SOM (22.0%) was significantly smaller in the pranlukast group compared with the control group (44.7%) (p = 0.018, chi-squared test). The results indicate that combined treatment of AOM with antibiotics and a leukotriene antagonist to control inflammation is useful for preventing progression to persistent SOM. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  19. A Systematic Review of Clinical Practice Guidelines' Recommendations on Levothyroxine Therapy Alone versus Combination Therapy (LT4 plus LT3) for Hypothyroidism.

    Science.gov (United States)

    Kraut, Eyal; Farahani, Pendar

    2015-12-04

    Patients with hypothyroidism are increasingly enquiring about the benefit of using combination therapy of levothyroxine (LT4) and liothyronine (LT3) as a potential treatment for hypothyroidism. Combination therapy, however, remains controversial. The purpose of this study was to systematically review available hypothyroidism treatment recommendations from clinical practice guidelines from around the world to identify the consensus regarding combination therapy. Clinical practice guidelines were obtained from searches of PubMed, EMBASE, and MEDLINE, using several combinations of MeSH terms. The search was limited to clinical guidelines in English-language publications, published between January 1, 1990 and May 1, 2015. A quantitative approach was utilized for data synthesis. Thirteen guidelines were identified, including three regarding pregnancy, two regarding pediatric populations and eight regarding adult populations. There were six guidelines from North America, four guidelines from Europe and three guidelines from South America. Twelve of the guidelines were published after 2010. Nine guidelines addressed combination therapy of LT4 plus LT3, and all nine concluded that LT4 therapy alone is the standard of care, with insufficient evidence to recommend widespread combination therapy. Only the 2012 ETA Guidelines and the 2015 BTA Guidelines concluded that combination therapy could be used, although only in certain circumstances and as an experimental treatment. This systematic review illustrates that clinical practice guidelines worldwide do not recommend and do not support routine use of combination LT4 and LT3 therapy to treat hypothyroidism.

  20. Churg-Strauss syndrome and leukotriene antagonist use: a respiratory perspective.

    LENUS (Irish Health Repository)

    Nathani, N

    2008-10-01

    Churg-Strauss syndrome (CSS) is a rare granulomatous small vessel vasculitis that occurs against a background of longstanding asthma. Leukotriene antagonists (LTAs) are used in the management of asthma and may facilitate a reduction in steroid dosage. Reports of the development of CSS in patients with asthma following the initiation of LTA therapy suggest either a causal association or an unmasking of latent CSS as steroid doses fall. We have undertaken a systematic review to establish whether evidence of a drug induced syndrome exists.

  1. A convenient synthesis of deuterated leukotriene A sub 4 methyl ester

    Energy Technology Data Exchange (ETDEWEB)

    Bestmann, H.J.; Roeder, T. (Erlangen-Nuernberg Univ., Erlangen (Germany, F.R.). Inst. fuer Organische Chemie); Meese, C.O. (Fischer-Bosch-Inst. fuer Klinische Pharmakologie, Stuttgart (Germany, F.R.))

    1989-11-01

    2,2,3,3-({sup 2}H{sub 4})-1-Iodopentane was prepared in four steps from propargyl alcohol and used in the C-alkylation of the THP-protected 3-butyne-1-ol. Subsequent protective group removal, semi-deuteration of the acetylenic alcohol and further transformation by known methods afforded the labelled key reagent 3,4,6,6,7,7-({sup 2}H{sub 6})-(Z)-(3-nonen-1-yl)triphenylphosphonium iodide. Wittig olefination of epoxy dienal with the ylide generated from the latter completed the convenient synthesis of hexadeuterated leukotriene A{sub 4} methyl ester. (author).

  2. Characterization of guinea pig myocardial leukotriene C4 binding sites. Regulation by cations and sulfhydryl-directed reagents

    International Nuclear Information System (INIS)

    Hogaboom, G.K.; Mong, S.; Stadel, J.M.; Crooke, S.T.

    1985-01-01

    Using [ 3 H]leukotriene C4 (LTC4) and radioligand-binding techniques, specific leukotriene C4 binding sites have been identified in membranes derived from guinea pig ventricular myocardium. High performance liquid chromatography analyses indicated that, in the presence of the gamma-glutamyl transpeptidase inhibitor L-serine-borate (80 mM), less than 2% of membrane-bound [ 3 H]LTC4 was converted at 20 degrees to [ 3 H]leukotriene D4 or [ 3 H]leukotriene E4. The specific binding of 4 nM [ 3 H]LTC4, in the presence of 80 mM L-serine-borate, reached a stable steady state within 15 min at 20 degrees (pH 7.5). A monophasic Scatchard plot of saturation binding data yielded a dissociation constant (Kd) of 27.5 +/- 6.0 nM and a maximum number of binding sites (Bmax) of 19.9 +/- 5.2 pmol/mg of membrane protein. Competition binding studies of [ 3 H]LTC4 with synthetic leukotriene C4, leukotriene D4, and leukotriene E4 and the putative peptidoleukotriene antagonists FPL 55712, SKF 88046, and 4R-hydroxy-5S-1-cysteinylglycine-6Z-nonadecanoic acid revealed an order of potency of leukotriene C4 much greater than 4R-hydroxy-5S-1-cysteinylglycine-6Z-nonadecanoic acid greater than SKF 88046 greater than LTE4 greater than LTD4 greater than FPL 55712. The specific [ 3 H]LTC4 binding was stimulated by the divalent cations Ca2+, Mg2+, and Mn2+ and to a lesser degree by the monovalent cations Na+, K+, Li+, and NH4+. CaCl2 (3 mM) and NaCl (150 mM) stimulated the LTC4 binding by increasing the Bmax to 42.6 +/- 5.9 and 35.0 +/- 2.0 pmol/mg, respectively, but had minimal effects on Kd

  3. EphB4 promotes or suppresses Ras/MEK/ERK pathway in a context-dependent manner: Implications for EphB4 as a cancer target.

    Science.gov (United States)

    Xiao, Zhan; Carrasco, Rosa; Kinneer, Krista; Sabol, Darrin; Jallal, Bahija; Coats, Steve; Tice, David A

    2012-06-01

    EphB4 is a member of the Eph receptor tyrosine kinase family shown to act in neuronal guidance and mediate venal/arterial separation. In contrast to these more established roles, EphB4's function in cancer is much less clear. Here we illustrate both tumor promoting as well as suppressing roles of EphB4, by showing that its activation resulted in inhibition of the Ras/ERK pathway in endothelial cells but activation of the same pathway in MCF-7 breast cancer cells. This was true if EphB4 was stimulated with EphrinB2, its natural ligand, or an agonistic monoclonal antibody for EphB4. Correspondingly, EphB4 activation stimulated MCF7 growth while inhibiting HUVEC cell proliferation. The reason for these dramatic differences is due to functional coupling of EphB4 to different downstream effectors. Reduction of p120 RasGAP in HUVEC cells attenuated the inhibitory effect of EphB4 activation on the ERK pathway, whereas knockdown of PP2A in MCF7 cells attenuated EphB4 activation of the ERK pathway. This represents the first time a functional coupling between Eph receptor and PP2A has been demonstrated leading to activation of an oncogenic pathway. Our study illustrates the caveats and potential challenges of targeting EphB4 for cancer therapy due to the conflicting effects on cancer cell and endothelial cell compartments.

  4. Feedback in LT codes for prioritized and non-prioritized data

    DEFF Research Database (Denmark)

    Sørensen, Jesper Hemming; Popovski, Petar; Østergaard, Jan

    2012-01-01

    In this paper feedback in LT codes is investigated. The considered type of feedback is acknowledgments, where information on which symbols have been decoded is given to the transmitter. Our analysis reveals that acknowledgments has a very low potential in LT codes with standard degree distributions....... Motivated by this, we analyze the impact of acknowledgments on multi-layer LT codes. In this case, feedback proves advantageous. By using only a single feedback message, it is possible to achieve a significant performance improvement compared to traditional LT codes....

  5. Systems Li2B4O7 (Na2B4O7, K2B4O7)-N2H3H4OH-H2O at 25 deg C

    International Nuclear Information System (INIS)

    Skvortsov, V.G.; Sadetdinov, Sh.V.; Akimov, V.M.; Mitrasov, Yu.N.; Petrova, O.V.; Klopov, Yu.N.

    1994-01-01

    Phase equilibriums in the Li 2 B 4 O 7 (Na 2 B 4 O 7 , K 2 B 4 O 7 )-N 2 H 3 H 4 OH-H 2 O systems were investigated by methods of isothermal solubility, refractometry and PH-metry at 25 deg C for the first time. Lithium and sodium tetraborates was established to form phases of changed composition mM 2 B 4 O 7 ·nN 2 H 3 C 2 H 4 OH·XH 2 O, where M=Li, Na with hydrazine ethanol. K 2 B 4 O 7 ·4H 2 O precipitates in solid phase in the case of potassium salt. Formation of isomorphous mixtures was supported by X-ray diffraction and IR spectroscopy methods

  6. Increasing doses effect of L-T4 and L-T3 in the hypothalamus - hypophysis - thyroid in patients carrier of congenital and acquired hypothyroidism

    International Nuclear Information System (INIS)

    Cavaliere, H.

    1987-01-01

    The pituitary and peripheral response to L-T4 and L-T3 therapy were studied in 12 patients with congenital goitrous hypothyroidism, in 10 patients with an ectopic thyroid and onset of hypothyroidism at 3-8 years of age, and in 6 patients with adult-onset hypothyroidism, after they had had their chronic thyroid hormone replacement therapy discontinued for 30 days. They were first treated with increasing L-T4 (0.1, 0.2, and 0.4 mg daily) followed by L-T3 (0.05 and 0.2 mg daily) after stopping thyroid medication for another month. Ten normal subjects were treated identically. Since all patients received similar doses of thyroid hormones (μg/Kg of body weight) and had similar serum levels of T4 and T3 on each dose of L-T4 or L-T3, this paper concludes that congenitally hypothyroid patients have persistent pituitary resistance, but no peripheral resistance, to thyroid hormone. (author)

  7. Development of an ErbB4 monoclonal antibody that blocks neuregulin-1-induced ErbB4 activation in cancer cells

    International Nuclear Information System (INIS)

    Okazaki, Shogo; Nakatani, Fumi; Masuko, Kazue; Tsuchihashi, Kenji; Ueda, Shiho; Masuko, Takashi; Saya, Hideyuki; Nagano, Osamu

    2016-01-01

    The use of monoclonal antibodies (mAbs) for cancer therapy is one of the most important strategies for current cancer treatment. The epidermal growth factor receptor (EGFR) family of receptor tyrosine kinases, which regulates cancer cell proliferation, survival, and migration, is a major molecular target for antibody-based therapy. ErbB4/HER4, which contains a ligand-binding extracellular region, is activated by several ligands, including neuregulins (NRGs), heparin-binding EGF-like growth factor, betacellulin and epiregulin. Although there are clinically approved antibodies for ErbB1 and ErbB2, there are no available therapeutic mAbs for ErbB4, and it is not known whether ErbB4 is a useful target for antibody-based cancer therapy. In this study, we developed an anti-ErbB4 mAb (clone P6-1) that suppresses NRG-dependent activation of ErbB4 and examined its effect on breast cancer cell proliferation in the extracellular matrix. - Highlights: • We newly generated four clones of human ErbB4 specific mAb. • ErbB4 mAb clone P6-1 blocks ErbB4 phosphorylation induced by NRG-1. • ErbB4 mAb clone P6-1 suppresses NRG-1-promoted breast cancer cells proliferation on three dimensional culture condition.

  8. Development of an ErbB4 monoclonal antibody that blocks neuregulin-1-induced ErbB4 activation in cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Okazaki, Shogo [Division of Gene Regulation, Institute for Advanced Medical Research, School of Medicine, Keio University, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582 (Japan); Nakatani, Fumi [Cell Biology Laboratory, Department of Pharmaceutical Sciences, Faculty of Pharmacy, Kinki University, Higashiosaka, Osaka 577-8502 Japan (Japan); Masuko, Kazue; Tsuchihashi, Kenji [Division of Gene Regulation, Institute for Advanced Medical Research, School of Medicine, Keio University, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582 (Japan); Ueda, Shiho; Masuko, Takashi [Cell Biology Laboratory, Department of Pharmaceutical Sciences, Faculty of Pharmacy, Kinki University, Higashiosaka, Osaka 577-8502 Japan (Japan); Saya, Hideyuki [Division of Gene Regulation, Institute for Advanced Medical Research, School of Medicine, Keio University, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582 (Japan); Nagano, Osamu, E-mail: osmna@sb3.so-net.ne.jp [Division of Gene Regulation, Institute for Advanced Medical Research, School of Medicine, Keio University, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582 (Japan)

    2016-01-29

    The use of monoclonal antibodies (mAbs) for cancer therapy is one of the most important strategies for current cancer treatment. The epidermal growth factor receptor (EGFR) family of receptor tyrosine kinases, which regulates cancer cell proliferation, survival, and migration, is a major molecular target for antibody-based therapy. ErbB4/HER4, which contains a ligand-binding extracellular region, is activated by several ligands, including neuregulins (NRGs), heparin-binding EGF-like growth factor, betacellulin and epiregulin. Although there are clinically approved antibodies for ErbB1 and ErbB2, there are no available therapeutic mAbs for ErbB4, and it is not known whether ErbB4 is a useful target for antibody-based cancer therapy. In this study, we developed an anti-ErbB4 mAb (clone P6-1) that suppresses NRG-dependent activation of ErbB4 and examined its effect on breast cancer cell proliferation in the extracellular matrix. - Highlights: • We newly generated four clones of human ErbB4 specific mAb. • ErbB4 mAb clone P6-1 blocks ErbB4 phosphorylation induced by NRG-1. • ErbB4 mAb clone P6-1 suppresses NRG-1-promoted breast cancer cells proliferation on three dimensional culture condition.

  9. Effect of the Ti/B4C mole ratio on the reaction products and reaction mechanism in an Al–Ti–B4C powder mixture

    International Nuclear Information System (INIS)

    Zhang, Jingjing; Lee, Jung-Moo; Cho, Young-Hee; Kim, Su-Hyeon; Yu, Huashun

    2014-01-01

    The effect of the Ti/B 4 C mole ratio on the fabrication behavior of Al composites is investigated using Al–Ti–B 4 C powder mixtures as reactants. The quick spontaneous infiltration (QSI) process combined with the combustion reaction and DTA analysis were used. According to the thermodynamic predictions, which are verified in the experimental results, TiB 2 is formed in all the samples whereas TiC is only formed in reactants with a Ti/B 4 C mole ratio of more than two. The C atoms from the reacted B 4 C do not move into TiC but instead they move into Al 3 BC or Al 4 C 3 when the Ti/B 4 C mole ratio is less than two. In addition, the reaction mechanism with a Ti/B 4 C mole ratio of 0.75 is investigated extensively. - Highlights: • The critical role of the Ti/B 4 C mole ratio on the reaction products of Al–Ti–B 4 C was studied using experiments. • The experimental results are also supported by thermodynamic calculations presented in this paper. • The reaction mechanism with a Ti/B 4 C mole ratio of 0.75 is investigated extensively

  10. Determination of cysteinyl leukotrienes in exhaled breath condensate: Method combining immunoseparation with LC-ESI-MS/MS

    Czech Academy of Sciences Publication Activity Database

    Syslová, K.; Kačer, P.; Vilhanová, B.; Kuzma, Marek; Lipovová, P.; Fenclová, Z.; Lebedová, J.; Pelclová, D.

    2011-01-01

    Roč. 879, č. 23 (2011), s. 2220-2228 ISSN 1570-0232 R&D Projects: GA MZd NS10298 Keywords : Cysteinyl leukotriene * Exhaled breath condensate * Immunoseparation Subject RIV: CE - Biochemistry Impact factor: 2.888, year: 2011

  11. Understanding micro-diffusion bonding from the fabrication of B4C/Ni composites

    Science.gov (United States)

    Wang, Miao; Wang, Wen-xian; Chen, Hong-sheng; Li, Yu-li

    2018-03-01

    A Ni-B4C macroscopic diffusion welding couple and a Ni-15wt%B4C composite fabricated by spark plasma sintering (SPS) were used to understand the micro-scale diffusion bonding between metals and ceramics. In the Ni-B4C macroscopic diffusion welding couple a perfect diffusion welding joint was achieved. In the Ni-15wt%B4C sample, microstructure analyses demonstrated that loose structures occurred around the B4C particles. Energy dispersive X-ray spectroscopy analyses revealed that during the SPS process, the process of diffusion bonding between Ni and B4C particles can be divided into three stages. By employing a nano-indentation test, the room-temperature fracture toughness of the Ni matrix was found to be higher than that of the interface. The micro-diffusion bonding between Ni and B4C particles is quite different from the Ni-B4C reaction couple.

  12. 76 FR 19724 - Airworthiness Directives; Airbus Model A300 B4-600, B4-600R, and F4-600R Series Airplanes, and...

    Science.gov (United States)

    2011-04-08

    ... B4-600, B4-600R, and F4-600R Series Airplanes, and Model C4-605R Variant F Airplanes (Collectively... F4-605R and F4-622R airplanes, and Model A300 C4-605R Variant F airplanes; and Model A310-203, -204...

  13. 26 CFR 48.4161(b)-4 - Tax-free sales.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 16 2010-04-01 2010-04-01 true Tax-free sales. 48.4161(b)-4 Section 48.4161(b)-4 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) MISCELLANEOUS EXCISE TAXES MANUFACTURERS AND RETAILERS EXCISE TAXES Sporting Goods § 48.4161(b)-4 Tax-free sales. For...

  14. The linkage between Churg-Strauss syndrome and leukotriene receptor antagonists: fact or fiction?

    Science.gov (United States)

    McDanel, Deanna L; Muller, Barbara A

    2005-01-01

    Epidemiologic evidence has shown that the worldwide prevalence of asthma is increasing. The leukotriene receptor antagonists (LTRAs) represent a new class of therapy for asthma. They have been developed in the last decade and play a pivotal steroid-sparing role in treating the inflammatory component of asthma. Consequently, reports of Churg-Strauss syndrome (CSS), a rare form of systemic vasculitis, have been recognized as a potential side effect in individuals with moderate to severe asthma on LTRA therapy. The serious nature of this disorder is worthy of prompt recognition by clinicians and aggressive therapy to avoid the subsequent longstanding effects of vasculitis. To validate the postulated linkage between the LTRAs and CSS, this review comprehensively evaluates reported cases in the literature and supports a pathophysiological relationship between the LTRAs and the development of CSS. PMID:18360552

  15. Initial characterization of Vaccinia Virus B4 suggests a role in virus spread

    International Nuclear Information System (INIS)

    Burles, Kristin; Irwin, Chad R.; Burton, Robyn-Lee; Schriewer, Jill; Evans, David H.; Buller, R. Mark; Barry, Michele

    2014-01-01

    Currently, little is known about the ankyrin/F-box protein B4. Here, we report that B4R-null viruses exhibited reduced plaque size in tissue culture, and decreased ability to spread, as assessed by multiple-step growth analysis. Electron microscopy indicated that B4R-null viruses still formed mature and extracellular virions; however, there was a slight decrease of virions released into the media following deletion of B4R. Deletion of B4R did not affect the ability of the virus to rearrange actin; however, VACV811, a large vaccinia virus deletion mutant missing 55 open reading frames, had decreased ability to produce actin tails. Using ectromelia virus, a natural mouse pathogen, we demonstrated that virus devoid of EVM154, the B4R homolog, showed decreased spread to organs and was attenuated during infection. This initial characterization suggests that B4 may play a role in virus spread, and that other unidentified mediators of actin tail formation may exist in vaccinia virus. - Highlights: • B4R-null viruses show reduced plaque size, and decreased ability to spread. • B4R-null viruses formed mature and extracellular virions; and rearranged actin. • Virus devoid of EVM154, the B4R homolog, was attenuated during infection. • Initial characterization suggests that B4 may play a role in virus spread. • Unidentified mediators of actin tail formation may exist in vaccinia virus

  16. Initial characterization of Vaccinia Virus B4 suggests a role in virus spread

    Energy Technology Data Exchange (ETDEWEB)

    Burles, Kristin; Irwin, Chad R.; Burton, Robyn-Lee [Li Ka Shing Institute of Virology, Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta, Canada T6G 2S2 (Canada); Schriewer, Jill [Department of Molecular Microbiology and Immunology, Saint Louis University School of Medicine, St. Louis, MO (United States); Evans, David H. [Li Ka Shing Institute of Virology, Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta, Canada T6G 2S2 (Canada); Buller, R. Mark [Department of Molecular Microbiology and Immunology, Saint Louis University School of Medicine, St. Louis, MO (United States); Barry, Michele, E-mail: michele.barry@ualberta.ca [Li Ka Shing Institute of Virology, Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta, Canada T6G 2S2 (Canada)

    2014-05-15

    Currently, little is known about the ankyrin/F-box protein B4. Here, we report that B4R-null viruses exhibited reduced plaque size in tissue culture, and decreased ability to spread, as assessed by multiple-step growth analysis. Electron microscopy indicated that B4R-null viruses still formed mature and extracellular virions; however, there was a slight decrease of virions released into the media following deletion of B4R. Deletion of B4R did not affect the ability of the virus to rearrange actin; however, VACV811, a large vaccinia virus deletion mutant missing 55 open reading frames, had decreased ability to produce actin tails. Using ectromelia virus, a natural mouse pathogen, we demonstrated that virus devoid of EVM154, the B4R homolog, showed decreased spread to organs and was attenuated during infection. This initial characterization suggests that B4 may play a role in virus spread, and that other unidentified mediators of actin tail formation may exist in vaccinia virus. - Highlights: • B4R-null viruses show reduced plaque size, and decreased ability to spread. • B4R-null viruses formed mature and extracellular virions; and rearranged actin. • Virus devoid of EVM154, the B4R homolog, was attenuated during infection. • Initial characterization suggests that B4 may play a role in virus spread. • Unidentified mediators of actin tail formation may exist in vaccinia virus.

  17. The effect of hydrogen on B4C coatings fabrication in inductively coupled plasma torch

    Directory of Open Access Journals (Sweden)

    Q. J. Guo

    2018-02-01

    Full Text Available Boron carbide (B4C coatings are prepared by an RF inductively coupled plasma (ICP torch with different amounts of hydrogen introduced into the sheath gas. The effects of the added hydrogen on the characteristics of the plasma are diagnosed by optical emission spectroscopy and high speed photography. The effects on the melting of B4C particles in the plasma are studied by scanning electron microscopy (SEM. The microstructure of the B4C coatings was determined with SEM imaging and x-ray diffraction analysis. The results show that adding hydrogen to the sheath gas leads to plasma contraction, which results in higher gas temperature of plasma. It also enhances B4C particles spheroidizing and improves the compactness of B4C coatings. Plasma processing does not change the main phase of boron carbide. The obtained results on B4C coatings on Cu substrates allows for improving the B4C coatings fabrication process.

  18. Immunomagnetic molecular probe with UHPLC-MS/MS: A promising way for reliable bronchial asthma diagnostics based on quantification of cysteinyl leukotrienes

    Czech Academy of Sciences Publication Activity Database

    Syslová, K.; Boehmová, A.; Demirbag, E.; Šimková, K.; Kuzma, Marek; Pelclová, D.; Sedlák, V.; Čáp, P.; Martásek, P.; Kačer, P.

    81-82, AUG 2013 (2013), s. 108-117 ISSN 0731-7085 Institutional support: RVO:61388971 Keywords : Cysteinyl leukotrienes * Immunomagnetic separation * UHPLC-MS Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 2.829, year: 2013

  19. CysLT(1)R antagonists inhibit tumor growth in a xenograft model of colon cancer.

    Science.gov (United States)

    Savari, Sayeh; Liu, Minghui; Zhang, Yuan; Sime, Wondossen; Sjölander, Anita

    2013-01-01

    The expression of the inflammatory G-protein coupled receptor CysLT1R has been shown to be upregulated in colon cancer patients and associated with poor prognosis. The present study investigated the correlation between CysLT1R and colon cancer development in vivo using CysLT1R antagonists (ZM198,615 or Montelukast) and the nude mouse xenograft model. Two drug administration regimens were established. The first regimen was established to investigate the importance of CysLT1R in tumor initiation. Nude mice were inoculated with 50 µM CysLT1R antagonist-pretreated HCT-116 colon cancer cells and received continued treatment (5 mg/kg/day, intraperitoneally). The second regimen aimed to address the role of CysLT1R in tumor progression. Nude mice were inoculated with non-pretreated HCT-116 cells and did not receive CysLT1R antagonist treatment until recordable tumor appearance. Both regimens resulted in significantly reduced tumor size, attributed to changes in proliferation and apoptosis as determined by reduced Ki-67 levels and increased levels of p21(WAF/Cip1) (Pcolon cancer cell line HCT-116 and CysLT1R antagonists. In addition to significant reductions in cell proliferation, adhesion and colony formation, we observed induction of cell cycle arrest and apoptosis in a dose-dependent manner. The ability of Montelukast to inhibit growth of human colon cancer xenograft was further validated by using two additional colon cancer cell lines, SW-480 and HT-29. Our results demonstrate that CysLT1R antagonists inhibit growth of colon cancer xenografts primarily by reducing proliferation and inducing apoptosis of the tumor cells.

  20. EphB4 localises to the nucleus of prostate cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Mertens-Walker, Inga, E-mail: inga.mertenswalker@qut.edu.au [Institute of Health and Biomedical Innovation, Queensland University of Technology, Woolloongabba, QLD (Australia); Australian Prostate Cancer Research Centre—Queensland, Translational Research Institute, 37 Kent Street, Woolloongabba 4102, QLD (Australia); Lisle, Jessica E. [Institute of Health and Biomedical Innovation, Queensland University of Technology, Woolloongabba, QLD (Australia); Australian Prostate Cancer Research Centre—Queensland, Translational Research Institute, 37 Kent Street, Woolloongabba 4102, QLD (Australia); Nyberg, William A. [Institute of Health and Biomedical Innovation, Queensland University of Technology, Woolloongabba, QLD (Australia); Stephens, Carson R. [Institute of Health and Biomedical Innovation, Queensland University of Technology, Woolloongabba, QLD (Australia); Australian Prostate Cancer Research Centre—Queensland, Translational Research Institute, 37 Kent Street, Woolloongabba 4102, QLD (Australia); Burke, Leslie [Institute of Health and Biomedical Innovation, Queensland University of Technology, Woolloongabba, QLD (Australia); Rutkowski, Raphael; Herington, Adrian C.; Stephenson, Sally-Anne [Institute of Health and Biomedical Innovation, Queensland University of Technology, Woolloongabba, QLD (Australia); Australian Prostate Cancer Research Centre—Queensland, Translational Research Institute, 37 Kent Street, Woolloongabba 4102, QLD (Australia)

    2015-04-10

    The EphB4 receptor tyrosine kinase is over-expressed in a variety of different epithelial cancers including prostate where it has been shown to be involved in survival, migration and angiogenesis. We report here that EphB4 also resides in the nucleus of prostate cancer cell lines. We used in silico methods to identify a bipartite nuclear localisation signal (NLS) in the extracellular domain and a monopartite NLS sequence in the intracellular kinase domain of EphB4. To determine whether both putative NLS sequences were functional, fragments of the EphB4 sequence containing each NLS were cloned to create EphB4NLS-GFP fusion proteins. Localisation of both NLS-GFP proteins to the nuclei of transfected cells was observed, demonstrating that EphB4 contains two functional NLS sequences. Mutation of the key amino residues in both NLS sequences resulted in diminished nuclear accumulation. As nuclear translocation is often dependent on importins we confirmed that EphB4 and importin-α can interact. To assess if nuclear EphB4 could be implicated in gene regulatory functions potential EphB4-binding genomic loci were identified using chromatin immunoprecipitation and Lef1 was confirmed as a potential target of EphB4-mediated gene regulation. These novel findings add further complexity to the biology of this important cancer-associated receptor. - Highlights: • The EphB4 protein can be found in the nucleus of prostate cancer cell lines. • EphB4 contains two functional nuclear localisation signals. • Chromatin immunoprecipitation has identified potential genome sequences to which EphB4 binds. • Lef1 is a confirmed target for EphB4-mediated gene regulation.

  1. EphB4 localises to the nucleus of prostate cancer cells

    International Nuclear Information System (INIS)

    Mertens-Walker, Inga; Lisle, Jessica E.; Nyberg, William A.; Stephens, Carson R.; Burke, Leslie; Rutkowski, Raphael; Herington, Adrian C.; Stephenson, Sally-Anne

    2015-01-01

    The EphB4 receptor tyrosine kinase is over-expressed in a variety of different epithelial cancers including prostate where it has been shown to be involved in survival, migration and angiogenesis. We report here that EphB4 also resides in the nucleus of prostate cancer cell lines. We used in silico methods to identify a bipartite nuclear localisation signal (NLS) in the extracellular domain and a monopartite NLS sequence in the intracellular kinase domain of EphB4. To determine whether both putative NLS sequences were functional, fragments of the EphB4 sequence containing each NLS were cloned to create EphB4NLS-GFP fusion proteins. Localisation of both NLS-GFP proteins to the nuclei of transfected cells was observed, demonstrating that EphB4 contains two functional NLS sequences. Mutation of the key amino residues in both NLS sequences resulted in diminished nuclear accumulation. As nuclear translocation is often dependent on importins we confirmed that EphB4 and importin-α can interact. To assess if nuclear EphB4 could be implicated in gene regulatory functions potential EphB4-binding genomic loci were identified using chromatin immunoprecipitation and Lef1 was confirmed as a potential target of EphB4-mediated gene regulation. These novel findings add further complexity to the biology of this important cancer-associated receptor. - Highlights: • The EphB4 protein can be found in the nucleus of prostate cancer cell lines. • EphB4 contains two functional nuclear localisation signals. • Chromatin immunoprecipitation has identified potential genome sequences to which EphB4 binds. • Lef1 is a confirmed target for EphB4-mediated gene regulation

  2. The Application of LT-Table in TRIZ Contradiction Resolving Process

    Science.gov (United States)

    Wei, Zihui; Li, Qinghai; Wang, Donglin; Tian, Yumei

    TRIZ is used to resolve invention problems. ARIZ is the most powerful systematic method which integrates all of TRIZ heuristics. Definition of ideal final result (IFR), identification of contradictions and resource utilization are main lines of ARIZ. But resource searching of ARIZ has fault of blindness. Alexandr sets up mathematical model of transformation of the hereditary information in an invention problem using the theory of catastrophes, and provides method of resource searching using LT-table. The application of LT-table on contradiction resolving is introduced. Resource utilization using LT-table is joined into ARIZ step as an addition of TRIZ, apply this method in separator paper punching machine design.

  3. Effects of 18 months of L-T4 replacement in women with subclinical hypothyroidism.

    LENUS (Irish Health Repository)

    Adrees, M

    2012-02-01

    CONTEXT: Some of the cardiovascular and renal abnormalities seen in overt hypothyroidism have also been reported in subclinical hypothyroidism (SCH). Short-term L-T4 replacement in SCH improves cardiovascular risk markers and reduces carotid intima-media thickness (CIMT), a surrogate marker of atherosclerosis. The haemodynamic and renal effects of L-T4 replacement in SCH are poorly understood. OBJECTIVES: To compare cardiovascular risk factors and renal variables in women with SCH and normal women. To study the effects of L-T4 replacement in SCH subjects on these variables and on structural and functional changes in common carotid and brachial arteries. DESIGN: Fifty-six women with SCH before and after L-T4 replacement for 18 months and 56 normal women of similar age distribution were studied. Blood Pressure (BP), plasma lipids and homocysteine were measured and renal function evaluated [estimation of glomerular filtration rate (eGFR) using standard equations and measurement of serum Cystatin-C] in women with SCH before and after 18 months of l-T4, and in healthy women. CIMT and endothelial function (using brachial artery ultrasound) were studied before and after L-T4 in a subgroup of women with SCH. RESULTS: Systolic and diastolic BP, total cholesterol, triglyceride, LDL-cholesterol, lipoprotein(a) and homocysteine were greater in SCH (P < 0.05), and following L-T4 replacement decreased (P < 0.05) to levels that no longer differed from normal subjects. Estimated GFR was reduced and serum Cystatin-C increased (P < 0.05) in SCH. These variables also normalized following L-T4. Following L-T4 replacement the carotid artery baseline diameter increased by 7.1% and CIMT decreased by a mean value of 13%, while brachial artery diameter increased basally by 12.5% and following endothelium-dependent vasodilatation by 17.5% (P < 0.05). However, the increment following reactive hyperaemia did not differ before or following L-T4 replacement. CONCLUSION: Normalization of

  4. A novel formulation of L-thyroxine (L-T4) reduces the problem of L-T4 malabsorption by coffee observed with traditional tablet formulations.

    Science.gov (United States)

    Vita, Roberto; Saraceno, Giovanna; Trimarchi, Francesco; Benvenga, Salvatore

    2013-02-01

    The purpose of this work is to evaluate if the coffee-associated malabsorption of tablet levothyroxine (L-T4) is reduced by soft gel capsule. We recruited 8 patients with coffee-associated L-T4 malabsorption including one hypothyroid patient. For 6 months, the patients were switched to the capsule maintaining the L-T4 daily dose. Patients took the capsule with water, having coffee 1 h later (proper habit, PH) on days 1-90, or with coffee ≤ 5 min later (improper habit, IH) on days 91-180. After 6 months, 2 patients volunteered for an acute loading test of 600 μg L-T4 (capsule) ingested with water (PH) or with coffee (IH). In the single hypothyroid patient, the post-switch TSH ranged 0.06-0.16 mU/L (PH) versus 5.8-22.4 mU/L pre-switch (PH) and 0.025-0.29 mU/L (IH) versus 26-34 mU/L pre-switch (IH). In the other 7 patients, post-switch TSH was 0.41 ± 0.46 (PH) versus 0.28 ± 0.20 pre-switch (PH) (P = 0.61) and 0.34 ± 0.30 (IH) versus 1.23 ± 1.47 pre-switch (IH) (P coffee influenced L-T4 pharmacokinetics minimally. Soft gel capsules can be used in patients who are unable/unwilling to change their IH of taking L-T4.

  5. Mainosideoista sähköisiin sisältöihin : sisältöstrategian merkitys mainostoimistojen digitaalisissa palveluissa

    OpenAIRE

    Pasanen, Riikka

    2012-01-01

    Sisältöstrategia on suunnittelukäytäntö, jonka tähtää liiketoiminnallisiin tavoitteisiin vaikuttavan verkkosisällön avulla. Tutkimuksessa tarkastellaan hyvän verkkosisällön kriteerejä ja pohditaan, voisiko mainostoimisto ottaa oppia sisältöstrategian käytännöistä ja tarjota sen avulla parempaa palvelua asiakkailleen. Tutkimusta varten on haastateltu neljää mainonnan strategisen suunnittelun ja asiakasjohdon ammattilaista, joiden näkemyksiä on peilattu tutkijan pitkään kokemukseen alalta sekä ...

  6. Genetic influences on ovulation of primary oocytes in LT/Sv strain mice.

    Science.gov (United States)

    Everett, Clare A; Auchincloss, Catherine A; Kaufman, Matthew H; Abbott, Catherine M; West, John D

    2004-11-01

    A high proportion of LT/Sv strain oocytes arrest in meiotic metaphase I (MI) and are ovulated as diploid primary oocytes rather than haploid secondary oocytes. (Mus musculus castaneus x LT/SvKau)F1 x LT/SvKau backcross females were analysed for the proportion of oocytes that arrested in MI and typed by PCR for a panel of microsatellite DNA sequences (simple sequence repeat polymorphisms) that differed between strain LT/SvKau and M. m. castaneus. This provided a whole genome scan of 86 genetic markers distributed over all 19 autosomes and the X chromosome, and revealed genetic linkage of the MI arrest phenotype to markers on chromosomes 1 and 9. Identification of these two chromosomal regions should facilitate the identification of genes involved in mammalian oocyte maturation and the control of meiosis.

  7. ENVIRONMENTAL TECHNOLOGY VERIFICATION REPORT LASER TOUCH AND TECHNOLOGIES, LLC LASER TOUCH MODEL LT-B512

    Science.gov (United States)

    The Environmental Technology Verification report discusses the technology and performance of Laser Touch model LT-B512 targeting device manufactured by Laser Touch and Technologies, LLC, for manual spray painting operations. The relative transfer efficiency (TE) improved an avera...

  8. Thermoelectric coefficient L(T) of polycrystalline silver doped BSCCO samples

    International Nuclear Information System (INIS)

    Rodriguez, J.E.; Marino, A.

    1998-01-01

    We present a study of the thermoelectric coefficient L(T) of polycrystalline silver doped BSCCO samples. The quantity L(T) relates the thermoelectric coefficient S(T) with the electrical conductivity σ (T) and gives an indication of the influence of the order parameter fluctuations (OPF) on S(T) in the mean field region (Mfr). The results of L(T) indicate that the critical behavior of S(T) above the superconducting transition is not only driven by σ (T). These results suggest that in the Mfr, L(T) is affected by thermodynamic fluctuations of the superconducting order parameter (OPF). The OPF effects show a two-dimensional (2D) character in the entire Mfr. (Author)

  9. Identification of leukotriene D4 specific binding sites in the membrane preparation isolated from guinea pig lung

    International Nuclear Information System (INIS)

    Mong, S.; Wu, H.L.; Clark, M.A.; Stadel, J.M.; Gleason, J.G.; Crooke, S.T.

    1984-01-01

    A radioligand binding assay has been established to study leukotriene specific binding sites in the guinea pig and rabbit tissues. Using high specific activity [ 3 H]-leukotriene D4 [( 3 H]-LTD4), in the presence or absence of unlabeled LTD4, the diastereoisomer of LTD4 (5R,6S-LTD4), leukotriene E4 (LTE4) and the end-organ antagonist, FPL 55712, the authors have identified specific binding sites for [ 3 H]-LTD4 in the crude membrane fraction isolated from guinea pig lung. The time required for [ 3 H]-LTD4 binding to reach equilibrium was approximately 20 to 25 min at 37 degrees C in the presence of 10 mM Tris-HCl buffer (pH 7.5) containing 150 mM NaCl. The binding of [ 3 H]-LTD4 to the specific sites was saturable, reversible and stereospecific. The maximal number of binding sites (Bmax), derived from Scatchard analysis, was approximately 320 +/- 200 fmol per mg of crude membrane protein. The dissociation constants, derived from kinetic and saturation analyses, were 9.7 nM and 5 +/- 4 nM, respectively. The specific binding sites could not be detected in the crude membrane fraction prepared from guinea pig ileum, brain and liver, or rabbit lung, trachea, ileum and uterus. In radioligand competition experiments, LTD4, FPL 55712 and 5R,6S-LTD4 competed with [ 3 H]-LTD4. The metabolic inhibitors of arachidonic acid and SKF 88046, an antagonist of the indirectly-mediated actions of LTD4, did not significantly compete with [ 3 H]-LTD4 at the specific binding sites. These correlations indicated that these specific binding sites may be the putative leukotriene receptors in the guinea-pig lung

  10. Pressure effect on structural, elastic, and thermodynamic properties of tetragonal B4C4

    Directory of Open Access Journals (Sweden)

    Baobing Zheng

    2015-03-01

    Full Text Available The compressibility, elastic anisotropy, and thermodynamic properties of the recently proposed tetragonal B4C4 (t-B4C4 are investigated under high temperature and high pressure by using of first-principles calculations method. The elastic constants, bulk modulus, shear modulus, Young’s modulus, Vickers hardness, Pugh’s modulus ratio, and Poisson’s ratio for t-B4C4 under various pressures are systematically explored, the obtained results indicate that t-B4C4 is a stiffer material. The elastic anisotropies of t-B4C4 are discussed in detail under pressure from 0 GPa to 100 GPa. The thermodynamic properties of t-B4C4, such as Debye temperature, heat capacity, and thermal expansion coefficient are investigated by the quasi-harmonic Debye model.

  11. The Saccharomyces boulardii CNCM I-745 Strain Shows Protective Effects against the B. anthracis LT Toxin

    Directory of Open Access Journals (Sweden)

    Rodolphe Pontier-Bres

    2015-10-01

    Full Text Available The probiotic yeast Saccharomyces boulardii (S. boulardii has been prescribed for the prophylaxis and treatment of several infectious diarrheal diseases. Gastrointestinal anthrax causes fatal systemic disease. In the present study, we investigated the protective effects conferred by Saccharomyces boulardii CNCM I-745 strain on polarized T84 columnar epithelial cells intoxicated by the lethal toxin (LT of Bacillus anthracis. Exposure of polarized T84 cells to LT affected cell monolayer integrity, modified the morphology of tight junctions and induced the formation of actin stress fibers. Overnight treatment of cells with S. boulardii before incubation with LT maintained the integrity of the monolayers, prevented morphological modification of tight junctions, restricted the effects of LT on actin remodeling and delayed LT-induced MEK-2 cleavage. Mechanistically, we demonstrated that in the presence of S. boulardii, the medium is depleted of both LF and PA sub-units of LT and the appearance of a cleaved form of PA. Our study highlights the potential of the S. boulardii CNCM I-745 strain as a prophylactic agent against the gastrointestinal form of anthrax.

  12. The Saccharomyces boulardii CNCM I-745 strain shows protective effects against the B. anthracis LT toxin.

    Science.gov (United States)

    Pontier-Bres, Rodolphe; Rampal, Patrick; Peyron, Jean-François; Munro, Patrick; Lemichez, Emmanuel; Czerucka, Dorota

    2015-10-30

    The probiotic yeast Saccharomyces boulardii (S. boulardii) has been prescribed for the prophylaxis and treatment of several infectious diarrheal diseases. Gastrointestinal anthrax causes fatal systemic disease. In the present study, we investigated the protective effects conferred by Saccharomyces boulardii CNCM I-745 strain on polarized T84 columnar epithelial cells intoxicated by the lethal toxin (LT) of Bacillus anthracis. Exposure of polarized T84 cells to LT affected cell monolayer integrity, modified the morphology of tight junctions and induced the formation of actin stress fibers. Overnight treatment of cells with S. boulardii before incubation with LT maintained the integrity of the monolayers, prevented morphological modification of tight junctions, restricted the effects of LT on actin remodeling and delayed LT-induced MEK-2 cleavage. Mechanistically, we demonstrated that in the presence of S. boulardii, the medium is depleted of both LF and PA sub-units of LT and the appearance of a cleaved form of PA. Our study highlights the potential of the S. boulardii CNCM I-745 strain as a prophylactic agent against the gastrointestinal form of anthrax.

  13. Murine model of acute myocarditis and cerebral cortical neuron edema induced by coxsackievirus B4

    Directory of Open Access Journals (Sweden)

    Zhao-Peng Dong

    2018-01-01

    Full Text Available Globally, coxsackievirus B4 (CV-B4 has been continuously isolated and evidence suggests an association with the development of pancreatitis and type I diabetes. In addition, CV-B4 is also associated with myocarditis and severe central nervous system (CNS complications, which remain poorly studied and understood. In the present study, we established an ICR mouse model of CV-B4 infection and examined whether CV-B4 infection resulted in a predisposition to myocarditis and CNS infection. We found high survival in both the treatment and control group, with no significant differences in clinical outcomes observed. However, pathological lesions were evident in both brain and heart tissue of the CV-B4-infected mice. In addition, high viral loads were found in the neural and cardiac tissues as early as 2 d postinfection. Expressions of IFN-γ and IL-6 in sera were significantly higher in CV-B4-infected mice compared to uninfected negative controls, suggesting the involvement of these cytokines in the development of histopathological lesions. Our murine model successfully reproduced the acute myocarditis and cerebral cortical neuron edema induced by CV-B4, and may be useful for the evaluation of vaccine candidates and potential antivirals against CV-B4 infection.

  14. Effect of increased HoxB4 on human megakaryocytic development

    International Nuclear Information System (INIS)

    Zhong, Yiming; Sullenbarger, Brent; Lasky, Larry C.

    2010-01-01

    Research highlights: → HoxB4 overexpression in human TF1 cells increased the expression of CD61 and CD41a. → HoxB4 fusion protein enhanced megakaryocytic development of CD34 + cord blood cells. → Ectopic HoxB4 increased Tpo receptor expression and decreased c-Myb expression. → HoxB4 RNA silencing increased c-Myb expression and decreased Fli-1 expression. -- Abstract: In order to produce clinically useful quantities of platelets ex vivo we may need to firstly enhance early self-renewal of hematopoietic stem cells (HSCs) and/or megakaryocyte (Mk) progenitors. The homeodomain transcription factor HoxB4 has been shown to be an important regulator of stem cell renewal and hematopoiesis; however, its effect on megakaryopoiesis is unclear. In this study, we investigated the effect of HoxB4 overexpression or RNA silencing on megakaryocytic development in the human TF1 progenitor cell line; we then used recombinant tPTD-HoxB4 fusion protein to study the effect of exogenous HoxB4 on megakaryocytic development of human CD34 positively-selected cord blood cells. We found that ectopic HoxB4 in TF1 cells increased the antigen expression of CD61and CD41a, increased the gene expression of thrombopoietin receptor (TpoR), Scl-1, Cyclin D1, Fog-1 and Fli-1 while it decreased c-Myb expression. HoxB4 RNA silencing in TF1 cells decreased the expression of CD61 and CD41a and decreased Fli-1 expression while it increased the expression of c-Myb. Recombinant tPTD-HoxB4 fusion protein increased the percentages and absolute numbers of CD41a and CD61 positive cells during megakaryocytic differentiation of CD34 positively-selected cord blood cells and increased the numbers of colony-forming unit-megakaryocyte (CFU-Mk). Adding tPTD-HoxB4 fusion protein increased the gene expression of TpoR, Cyclin D1, Fog-1 and Fli-1 while it inhibited c-Myb expression. Our data suggest that increased HoxB4 enhanced early megakaryocytic development in human TF1 cells and CD34 positively-selected cord

  15. Effect of increased HoxB4 on human megakaryocytic development

    Energy Technology Data Exchange (ETDEWEB)

    Zhong, Yiming [Department of Pathology, The Ohio State University, Columbus, OH (United States); Program in Molecular, Cellular, and Developmental Biology, The Ohio State University, Columbus, OH (United States); Sullenbarger, Brent [Department of Pathology, The Ohio State University, Columbus, OH (United States); Lasky, Larry C., E-mail: Lasky.4@osu.edu [Department of Pathology, The Ohio State University, Columbus, OH (United States); Program in Molecular, Cellular, and Developmental Biology, The Ohio State University, Columbus, OH (United States)

    2010-07-30

    Research highlights: {yields} HoxB4 overexpression in human TF1 cells increased the expression of CD61 and CD41a. {yields} HoxB4 fusion protein enhanced megakaryocytic development of CD34{sup +} cord blood cells. {yields} Ectopic HoxB4 increased Tpo receptor expression and decreased c-Myb expression. {yields} HoxB4 RNA silencing increased c-Myb expression and decreased Fli-1 expression. -- Abstract: In order to produce clinically useful quantities of platelets ex vivo we may need to firstly enhance early self-renewal of hematopoietic stem cells (HSCs) and/or megakaryocyte (Mk) progenitors. The homeodomain transcription factor HoxB4 has been shown to be an important regulator of stem cell renewal and hematopoiesis; however, its effect on megakaryopoiesis is unclear. In this study, we investigated the effect of HoxB4 overexpression or RNA silencing on megakaryocytic development in the human TF1 progenitor cell line; we then used recombinant tPTD-HoxB4 fusion protein to study the effect of exogenous HoxB4 on megakaryocytic development of human CD34 positively-selected cord blood cells. We found that ectopic HoxB4 in TF1 cells increased the antigen expression of CD61and CD41a, increased the gene expression of thrombopoietin receptor (TpoR), Scl-1, Cyclin D1, Fog-1 and Fli-1 while it decreased c-Myb expression. HoxB4 RNA silencing in TF1 cells decreased the expression of CD61 and CD41a and decreased Fli-1 expression while it increased the expression of c-Myb. Recombinant tPTD-HoxB4 fusion protein increased the percentages and absolute numbers of CD41a and CD61 positive cells during megakaryocytic differentiation of CD34 positively-selected cord blood cells and increased the numbers of colony-forming unit-megakaryocyte (CFU-Mk). Adding tPTD-HoxB4 fusion protein increased the gene expression of TpoR, Cyclin D1, Fog-1 and Fli-1 while it inhibited c-Myb expression. Our data suggest that increased HoxB4 enhanced early megakaryocytic development in human TF1 cells and CD34

  16. Heat release from B4C oxidation in steam and air

    International Nuclear Information System (INIS)

    Belovsky, L.

    1996-01-01

    BWR and some PWR cores contain boron carbide (B 4 C) as neutron absorber. During a severe accident, the B 4 C can potentially react with steam under release of heat and hydrogen. Although models for B 4 C oxidation already exist in MELCOR and SCDAP/RELAP5, a development of a new model for another computer code seems to be difficult due to a missing comprehensive description of the current modelling methodology and scarce experimental data. The aim of this paper is to highlight the key points of the B 4 C oxidation using the existing available experimental data and to perform a simple heat balance analysis of the B 4 C/steam and B 4 C/air chemical reactions. The analysis of literature data shows that the B 4 C oxidation phenomenon is qualitatively well described below 1000 deg. C. However, no reliable data exist for the reaction kinetics especially above this temperature. It was found that the experimental results strongly depend on the experimental arrangement. The reaction heats, calculated in this study, indicate that the B 4 C oxidation is an exothermic reaction, releasing more heat in air than in steam. The formation of boric acids from the boron oxide increases the heat release from B 4 C by ∼ 10%, in the worst case. Although the total heat, released in a PWR core from the B 4 C oxidation, is probably much smaller than the heat released from the Zr/steam reaction, it is not excluded that the B 4 C oxidation can locally contribute to the damage of the control elements due to local overheating. Modelling of these phenomena is, however, very difficult due to the complex geometry of the liquefied control elements and due to absence of suitable data on the reaction kinetics. (author). 25 refs, 2 figs, 3 tabs

  17. Ligand stimulation of ErbB4 and a constitutively-active ErbB4 mutant result in different biological responses in human pancreatic tumor cell lines

    International Nuclear Information System (INIS)

    Mill, Christopher P.; Gettinger, Kathleen L.; Riese, David J.

    2011-01-01

    Pancreatic cancer is the fourth leading cause of cancer death in the United States. Indeed, it has been estimated that 37,000 Americans will die from this disease in 2010. Late diagnosis, chemoresistance, and radioresistance of these tumors are major reasons for poor patient outcome, spurring the search for pancreatic cancer early diagnostic and therapeutic targets. ErbB4 (HER4) is a member of the ErbB family of receptor tyrosine kinases (RTKs), a family that also includes the Epidermal Growth Factor Receptor (EGFR/ErbB1/HER1), Neu/ErbB2/HER2, and ErbB3/HER3. These RTKs play central roles in many human malignancies by regulating cell proliferation, survival, differentiation, invasiveness, motility, and apoptosis. In this report we demonstrate that human pancreatic tumor cell lines exhibit minimal ErbB4 expression; in contrast, these cell lines exhibit varied and in some cases abundant expression and basal tyrosine phosphorylation of EGFR, ErbB2, and ErbB3. Expression of a constitutively-dimerized and -active ErbB4 mutant inhibits clonogenic proliferation of CaPan-1, HPAC, MIA PaCa-2, and PANC-1 pancreatic tumor cell lines. In contrast, expression of wild-type ErbB4 in pancreatic tumor cell lines potentiates stimulation of anchorage-independent colony formation by the ErbB4 ligand Neuregulin 1β. These results illustrate the multiple roles that ErbB4 may be playing in pancreatic tumorigenesis and tumor progression.

  18. Persistence of Salmonella Typhimurium LT2 in Soil Enhanced after Growth in Lettuce Medium

    Directory of Open Access Journals (Sweden)

    Kornelia Smalla

    2017-04-01

    Full Text Available The persistence of Salmonella in the environment is influenced by a multitude of biotic and abiotic factors. In addition, its persistence can be influenced by preadaptation before the introduction into the environment. In order to study how preadaptation changes the survival of Salmonella in soil and therefore its potential to colonize the phytosphere, we developed a new medium based on lettuce material [lettuce medium (LM]. Salmonella enterica serovar Typhimurium strain LT2 was used as a model for Salmonella in this study. LT2 was inoculated into soil microcosms after pregrowth in Luria Bertani (LB broth or in LM. Survival of LT2 in soil was monitored over 56 days by plate counts and quantification of the Typhimurium-specific gene STM4497 using qPCR in total community DNA for which primers and TaqMan probe were designed in this study. Significantly enhanced persistence was observed for LT2 pregrown in LM compared to LT2 pregrown in LB, indicating a preadaptation effect. Surprisingly, no improved survival could be observed for S. Typhimurium strain 14028s and S. enterica serovar Senftenberg after pregrowth on LM. This indicates a high strain specificity of preadaptation. Results from previous studies suggested that biofilm formation could enhance the survival of human pathogens in various environments and might contribute to enhanced survival on plants. In vitro biofilm assays with several Salmonella strains revealed a strain-specific effect of LM on the biofilm formation. While LM significantly improved the biofilm formation of S. Senftenberg, the biofilm formation of LT2 was better in LB. This indicates that the better survival of LM-pregrown LT2 in soil was not linked to an improved ability to form biofilms but was likely due to other factors. Most importantly, this study showed that the medium used to pregrow Salmonella can influence its survival in soil and its biofilm formation which might influence the fate of Salmonella in soil.

  19. B4G local area: high level requirements and system design

    DEFF Research Database (Denmark)

    Mogensen, Preben; Pajukoski, Kari; Raaf, Bernhard

    2012-01-01

    A next generation Beyond 4G (B4G) radio access technology is expected to become available around 2020 in order to cope with the exponential increase of mobile data traffic. In this paper, research motivations and high level requirements for a B4G local area concept are discussed. Our suggestions ...

  20. Effects of drugs inhibiting prostaglandin or leukotriene biosynthesis on postirradiation haematopoiesis in mouse

    International Nuclear Information System (INIS)

    Kozubik, A.; Hofmanova, J.; Pospisil, M.; Netikova, J.; Hola, J.; Lojek, A.

    1994-01-01

    Two non-steroidal anti-inflammatory drugs, i.e. indomethacin (INDO), an inhibitor of prostaglandin production, and esculetin (ESCUL), an inhibitor of leukotriene production, were tested for their ability to modify haematopoiesis in three experimental systems: (a) in vitro clonal proliferation of marrow GM-CFC from the irradiated mouse was found to be augmented by addition of INDO at a low concentration, and inhibited by ESCUL in a dose-dependent manner; (b) in the lethally irradiated and bone marrow-transplanted mice treated with the drugs in the postirradiation period, stimulatory effects of INDO on CFU-S and GM-CFC populations and an inhibitory effect of ESCUL on GM-CFC were observed; and (c) when the drugs were administered i.p. to mice 1 h before 5-Gy irradiation, INDO enhanced the postirradiation recovery of haematopoietic indices such the numbers of CFU-S, GM-CFC, peripheral blood granuloctyes, and nucleated bone marrow cells, while ESCUL had no effect or even inhibited the recovery of these indices. (author)

  1. Population-based open-label clinical effectiveness assessment of the cysteinyl leukotriene receptor antagonist pranlukast

    Directory of Open Access Journals (Sweden)

    Gen Tamura

    2000-01-01

    Full Text Available Although the efficacy of cysteinyl leukotriene receptor antagonists in asthma therapy has been established through controlled clinical trials, there are no data concerning the effectiveness of their use in clinical practice, in which there is no rigid selection based on specific inclusion and exclusion criteria. The aim of the present study was to evaluate the effectiveness of pranlukast in clinical practice. More than 2500 outpatients with mild to severe persistent asthma answered an input questionnaire, which consisted of 33 items assessing asthma symptoms in terms of six activities of daily living during the previous 2 weeks. Of these patients, 1138 received treatment with pranlukast and answered the same questionnaire 4–6 weeks after the start of treatment. In 923 of these 1138 patients, we examined the impact of concomitantly used inhaled steroids, β2-adrenergic agonists or sustained-release theophylline on the effectiveness of pranlukast treatment. One hundred and sixty-seven control patients completed the questionnaire twice but did not receive pranlukast treatment. We found a significant decrease in the number of asthma symptoms reported among both the 1138 patients treated with pranlukast and the 167 control patients. However, the magnitude of the decrease in symptoms was significantly (P < 0.001 greater with pranlukast treatment. Moreover, pranlukast was equally efficacious in the presence and absence of concomitantly used inhaled steroids, β2-adrenergic agonists or sustained-release theophylline. In conclusion, pranlukast was shown to have clinical effectiveness in the treatment of mild to severe persistent asthma symptoms.

  2. Exhaled breath condensate cysteinyl leukotrienes and airway remodeling in childhood asthma: a pilot study

    Directory of Open Access Journals (Sweden)

    Kharitonov Sergei A

    2006-04-01

    Full Text Available Abstract Background It has been suggested that cysteinyl leukotrienes (cysLTs play an important role in airway remodeling. Previous reports have indicated that cysLTs augment human airway smooth muscle cell proliferation. Recently, cysLTs have been measured in exhaled breath condensate (EBC. The aim of this study was to evaluate the relationship between cysLTs in EBC and another marker of airway remodeling, reticular basement membrane (RBM thickening, in endobronchial biopsies in children. Methods 29 children, aged 4–15 years, with moderate to severe persistent asthma, who underwent bronchoscopy as part of their clinical assessment, were included. Subjects underwent spirometry and EBC collection for cysLTs analysis, followed by bronchoscopy and endobronchial biopsy within 24 hours. Results EBC cysLTs were significantly lower in asthmatic children who were treated with montelukast than in those who were not (median (interquartile range 36.62 (22.60–101.05 versus 249.1 (74.21–526.36 pg/ml, p = 0.004. There was a significant relationship between EBC cysLTs and RBM thickness in the subgroup of children who were not treated with montelukast (n = 13, r = 0.75, p = 0.003. Conclusion EBC cysLTs appear to be associated with RBM thickening in asthma.

  3. Inhibition of common cold-induced aggravation of childhood asthma by leukotriene receptor antagonists.

    Science.gov (United States)

    Yoshihara, Shigemi; Fukuda, Hironobu; Abe, Toshio; Nishida, Mitsuhiro; Yamada, Yumi; Kanno, Noriko; Arisaka, Osamu

    2012-09-01

    Virus infection is an important risk factor for aggravation of childhood asthma. The objective of this study was to examine the effect of drugs on aggravation of asthma induced by a common cold. Asthma control was examined in a survey of 1,014 Japanese pediatric patients with bronchial asthma. The occurrence of common cold, asthma control, and drugs used for asthma control were investigated using a modified Childhood Asthma Control Test (C-ACT) for patients aged cold and aggravation of asthma were significantly higher in patients aged cold-induced aggravation was significantly less effective in patients aged cold, asthma control was significantly more effective for those treated with leukotriene receptor antagonists (LTRAs) compared to treatment without LTRAs. Asthma control did not differ between patients who did or did not take inhaled corticosteroids or long-acting β2 stimulants. These findings showed a high prevalence of common cold in younger patients with childhood asthma and indicated that common cold can induce aggravation of asthma. LTRAs are useful for long-term asthma control in very young patients who develop an asthma attack due to a common cold.

  4. Role of leukotrienes in NSAID induced gastric ulceration and inflammation in wistar rats

    Directory of Open Access Journals (Sweden)

    Maulik N Gandhi

    2012-06-01

    Full Text Available Objective: To evaluate the effects of Montelukast and Curcumin against indomethacin induced gastric damage in rats in order to assess the role of leukotriene (LTs if any, in non steroidal antiinflammatory drug (NSAID induced gastroinflammation. Methods: The effects of Montelukast (10 mg/kg and Curcumin (100 mg/kg were observed on gastric lesion induced by Indomethacin. The blood samples were analyzed for neutrophil adhesion and lipid peroxide levels in gastric tissue measured spectrophotometrically. The skin vascular permeability study was performed by using compound 48/80 induced vascular permeability model. Results: Montelukast and Curcumin significantly reduced Indomethacin induced gastric lesion score. Pretreatment with Montelukast and Curcumin significantly counteracted Indomethacin induced gastropathy by a combination of its effect on inhibition of neutrophil adherence, through decrease in related production of free radicals that disrupts integrity of stomach mucosa and decrease in vascular permeability as compared to Indomethacin group. The results of the present study further indicates the role of 5-LOX metabolites in NSAIDs induced gastro inflammation and suggests that Montelukast and Curcumin counteracted the Indomethacin induced gastropathy by a combination of its effect on inhibition of neutrophil adherence and through decrease in related production of free radicals that disrupts integrity of stomach mucosa. Conclusions: Experimental data clearly demonstrated the role of LTs was indomethacin induced gastric ulcers. However, inhibition of ulcerogenic events by Montelukast and Curcumin is suggestive of an important balance between COX and 5-LOX products.

  5. Effects of drugs inhibiting prostaglandin or leukotriene biosynthesis on postirradiation haematopoiesis in mouse

    Energy Technology Data Exchange (ETDEWEB)

    Kozubik, A.; Hofmanova, J.; Pospisil, M.; Netikova, J.; Hola, J.; Lojek, A. (Ceskoslovenska Akademie Ved, Brno (Czech Republic). Biofysikalni Ustav)

    1994-03-01

    Two non-steroidal anti-inflammatory drugs, i.e. indomethacin (INDO), an inhibitor of prostaglandin production, and esculetin (ESCUL), an inhibitor of leukotriene production, were tested for their ability to modify haematopoiesis in three experimental systems: (a) in vitro clonal proliferation of marrow GM-CFC from the irradiated mouse was found to be augmented by addition of INDO at a low concentration, and inhibited by ESCUL in a dose-dependent manner; (b) in the lethally irradiated and bone marrow-transplanted mice treated with the drugs in the postirradiation period, stimulatory effects of INDO on CFU-S and GM-CFC populations and an inhibitory effect of ESCUL on GM-CFC were observed; and (c) when the drugs were administered i.p. to mice 1 h before 5-Gy irradiation, INDO enhanced the postirradiation recovery of haematopoietic indices such the numbers of CFU-S, GM-CFC, peripheral blood granuloctyes, and nucleated bone marrow cells, while ESCUL had no effect or even inhibited the recovery of these indices. (author).

  6. Comparison Results on the Basic Phenomena between CAP and CONTEMPT-LT

    Energy Technology Data Exchange (ETDEWEB)

    Choo, Yeon Joon; Hong, Soon Joon; Hwang, Su Hyun; Kim, Min Ki; Lee, Byung Chul [FNC Tech., SNU, Seoul (Korea, Republic of); Ha, Sang Jun; Choi, Hoon [KHNP Central Research Institute, Daejeon (Korea, Republic of)

    2011-10-15

    A development project for the domestic design code was launched to be used for the safety and performance analysis of pressurized light water reactors. As a part of this project, CAP (Containment Analysis Package) code has been developing for the containment safety and performance analysis side by side with SPACE. CAP Beta version has been released lately and validation processes are under way currently. Code by code comparison activity is scheduled in the validation processes and the first comparable code is CONTEMPT-LT. CONTEMPT-LT was developed to predict the longterm behavior of water-cooled nuclear reactor containment systems subjected to postulated loss-ofcoolant accident (LOCA) conditions. CONTEMPT-LT calculates the time variation of compartment pressures, temperatures, mass and energy inventories, heat structure temperature distributions, and energy exchange with adjacent compartments, leakage on containment response. Models are provided for fan cooler and cooling spray as engineered safety systems. Any compartment may have both a liquid pool region and an air-vapor atmosphere region above the pool. Each region is assumed to have a uniform temperature, but the temperatures of the two regions may be different. As mentioned above, CONTEMP-LT has the similar code features and it, therefore, is expected to show the similar analysis performance with CAP. In this study, the code performances were compared for the same phenomena between CAP and CONTEMPT-LT. Code comparison is carried out through two stages; separate and integral effect comparison

  7. Comparison Results on the Basic Phenomena between CAP and CONTEMPT-LT

    International Nuclear Information System (INIS)

    Choo, Yeon Joon; Hong, Soon Joon; Hwang, Su Hyun; Kim, Min Ki; Lee, Byung Chul; Ha, Sang Jun; Choi, Hoon

    2011-01-01

    A development project for the domestic design code was launched to be used for the safety and performance analysis of pressurized light water reactors. As a part of this project, CAP (Containment Analysis Package) code has been developing for the containment safety and performance analysis side by side with SPACE. CAP Beta version has been released lately and validation processes are under way currently. Code by code comparison activity is scheduled in the validation processes and the first comparable code is CONTEMPT-LT. CONTEMPT-LT was developed to predict the longterm behavior of water-cooled nuclear reactor containment systems subjected to postulated loss-ofcoolant accident (LOCA) conditions. CONTEMPT-LT calculates the time variation of compartment pressures, temperatures, mass and energy inventories, heat structure temperature distributions, and energy exchange with adjacent compartments, leakage on containment response. Models are provided for fan cooler and cooling spray as engineered safety systems. Any compartment may have both a liquid pool region and an air-vapor atmosphere region above the pool. Each region is assumed to have a uniform temperature, but the temperatures of the two regions may be different. As mentioned above, CONTEMP-LT has the similar code features and it, therefore, is expected to show the similar analysis performance with CAP. In this study, the code performances were compared for the same phenomena between CAP and CONTEMPT-LT. Code comparison is carried out through two stages; separate and integral effect comparison

  8. Effects of B4C control rod degradation under severe accident

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Si-Won; Park, Sang-Gil; Han, Sang-Ku [Atomic Creative Technology Co., Daejeon (Korea, Republic of)

    2016-10-15

    Boron carbide (B4C) is widely used as absorber material in western boiling water reactor (BWR), some PWR, EPR and Russian RBMK and VVERs. B4C oxidation is one of the important phenomena of in-vessel. In the present paper, the main results and knowledge gained regarding the B4C control rod degradation from above mentioned experiments are reviewed and arranged to inform its significance on the severe accident consequences. In this paper, the role of B4C control rod oxidation and the subsequent degradation on the severe accident consequences is reviewed with available literature and report of previous experimental program regarding the B4C oxidation. From this review, it seems that the contribution of this B4C oxidation on the accident progression to the further severe accident situation is not negligible. For the future work, the extensive experimental data interpretation will be performed to assess quantitatively the effect of B4C oxidation and degradation on the various postulated severe accident conditions.

  9. Production and characterization of AA6061-B4C stir cast composite

    International Nuclear Information System (INIS)

    Kalaiselvan, K.; Murugan, N.; Parameswaran, Siva

    2011-01-01

    Highlights: → Stir casting of AA6061-B 4 C Composite. Color metallographic of composites → Enhanced wetting of B 4 C particles by K 2 TiF 6 flux. → Effect of B 4 C particles on mechanical properties of AA6061. -- Abstract: This work focuses on the fabrication of aluminum (6061-T6) matrix composites (AMCs) reinforced with various weight percentage of B 4 C particulates by modified stir casting route. The wettability of B 4 C particles in the matrix has been improved by adding K 2 TiF 6 flux into the melt. The microstructure and mechanical properties of the fabricated AMCs are analyzed. The optical microstructure and scanning electron microscope (SEM) images reveal the homogeneous dispersion of B 4 C particles in the matrix. The reinforcement dispersion has also been identified with X-ray diffraction (XRD). The mechanical properties like hardness and tensile strength have improved with the increase in weight percentage of B 4 C particulates in the aluminum matrix.

  10. Investigation of the expression of the EphB4 receptor tyrosine kinase in prostate carcinoma

    International Nuclear Information System (INIS)

    Lee, Yen-Ching; Perren, Janeanne R; Douglas, Evelyn L; Raynor, Michael P; Bartley, Maria A; Bardy, Peter G; Stephenson, Sally-Anne

    2005-01-01

    The EphB4 receptor tyrosine kinase has been reported as increased in tumours originating from several different tissues and its expression in a prostate cancer xenograft model has been reported. RT-PCR, western blotting and immunohistochemical techniques were used to examine EphB4 expression and protein levels in human prostate cancer cell lines LNCaP, DU145 and PC3. Immunohistochemistry was also used to examine localisation of EphB4 in tissue samples from 15 patients with prostate carcinomas. All three prostate cancer cell lines expressed the EphB4 gene and protein. EphB4 immunoreactivity in vivo was significantly greater in human prostate cancers as compared with matched normal prostate epithelium and there appeared to be a trend towards increased expression with higher grade disease. EphB4 is expressed in prostate cancer cell lines with increased expression in human prostate cancers when compared with matched normal tissue. EphB4 may therefore be a useful anti-prostate cancer target

  11. Evaulation of B4C as an ablator material for NIF capsules. Revision 1

    International Nuclear Information System (INIS)

    Burnham, A.K.; Alford, C.S.; Makowiecki, D.M.; Dittrich, T.R.; Wallace, R.J.; Honea, E.C.; King, C.M.; Steinman, D.

    1997-01-01

    Boron carbide (B 4 C) is examined as a potential fuel container and ablator for implosion capsules on the National Ignition Facility (NIF). A capsule of pure B 4 C encasing a layer of solid DT implodes stably and ignites with anticipated NIF x-ray drives, producing 18 MJ of energy. Thin films of B 4 C were found to be resistant to oxidation and modestly transmitting in the infrared (IR), possibly enabling IR fuel characterization and enhancement for thin permeation barriers but not for full-thickness capsules. Polystyrene mandrels 0.5 mm in diameter were successfully coated with 0.15-2.0 micrometers of B 4 C. Thickness estimated from optical density agreed well with those measured by scanning electron microscopy (SEM). The B 4 C microstructure was columnar but finer than for Be made at the same conditions. B 4 C is a very strong material, with a fiber tensile strength capable of holding NIF fill pressures at room temperature, but it is also very brittle, and microscopic flaws or grain structure may limit the noncryogenic fill pressure. Argon (Ar) permeation rates were measured for a few capsules that had been further coated with 5 micrometers of plasma polymer. The B 4 C coatings tended to crack under tensile load. Some shells filled more slowly than they leaked, suggesting that the cracks open and close under opposite pressure loading. As observed earlier for Ti coatings, 0.15-micrometer layers of B 4 C had better gas retention properties than 2-micrometer layers, possibly because of fewer cracks. Permeation and fill strength issues for capsules with a full ablator thickness of B 4 C are unresolved. 21 refs., 6 figs

  12. Al/ B4C Composites with 5 and 10 wt% Reinforcement Content Prepared by Powder Metallurgy

    International Nuclear Information System (INIS)

    Yusof Abdullah; Mohd Reusmaazran Yusof; Azali Muhammad; Nadira Kamarudin; Wilfred Sylvester Paulus; Roslinda Shamsudin; Nasrat Hannah Shudin; Nurazila Mat Zali

    2012-01-01

    The preparation, physical and mechanical properties of Al/ B 4 C composites with 5 and 10 wt.% reinforcement content were investigated. In order to obtain the feedstock with a low powder loading, B 4 C mixtures containing fine powders were investigated to obtain the optimal particle packing. The experimental results indicated that the fine containing 5 and 10 wt.% particles are able to prepare the feedstock with a good flowability. The composites fabricated by powder metallurgy have low densities and homogeneous microstructures. Additionally there is no interface reaction observed between the reinforcement and matrix by XRD analysis. The hardness of Al/ B 4 C composites prepared by powder metallurgy was high. (Author)

  13. Exoelectron emission from surface layer of Li2B4O7 glass ceramics

    International Nuclear Information System (INIS)

    Kawamoto, Takamichi; Katsube, Shizuko; Yanagisawa, Hideo; Kikuchi, Riichi; Kawanishi, Masaharu.

    1984-01-01

    The thermally stimulated exoelectron emission (TESS) of Li 2 B 4 O 7 glass ceramics was investigated for its application to the dosimetric use. It has been found the TSEE glow patterns of Li 2 B 4 O 7 glass ceramics and of the thin layer of LiF evaporated on Li 2 B 4 O 7 glass ceramics depend on the kind of radiations irradiated. The TSEE glow pattern of the duplicated structure sample indicated a possibility of determining the dose of each kind of radiation separately in the mixed radiation field. (author)

  14. Rotavirus 2/6 Viruslike Particles Administered Intranasally with Cholera Toxin, Escherichia coli Heat-Labile Toxin (LT), and LT-R192G Induce Protection from Rotavirus Challenge

    OpenAIRE

    O’Neal, Christine M.; Clements, John D.; Estes, Mary K.; Conner, Margaret E.

    1998-01-01

    We have shown that rotavirus 2/6 viruslike particles composed of proteins VP2 and VP6 (2/6-VLPs) administered to mice intranasally with cholera toxin (CT) induced protection from rotavirus challenge, as measured by virus shedding. Since it is unclear if CT will be approved for human use, we evaluated the adjuvanticity of Escherichia coli heat-labile toxin (LT) and LT-R192G. Mice were inoculated intranasally with 10 μg of 2/6-VLPs combined with CT, LT, or LT-R192G. All three adjuvants induced ...

  15. A SEARCH FOR L/T TRANSITION DWARFS WITH PAN-STARRS1 AND WISE. II. L/T TRANSITION ATMOSPHERES AND YOUNG DISCOVERIES

    International Nuclear Information System (INIS)

    Best, William M. J.; Liu, Michael C.; Magnier, Eugene A.; Aller, Kimberly M.; Chambers, K. C.; Flewelling, H.; Hodapp, K. W.; Kaiser, N.; Tonry, J. L.; Wainscoat, R. J.; Waters, C.; Deacon, Niall R.; Redstone, Joshua; Burgett, W. S.; Draper, P.; Metcalfe, N.

    2015-01-01

    The evolution of brown dwarfs from L to T spectral types is one of the least understood aspects of the ultracool population, partly for lack of a large, well-defined, and well-characterized sample in the L/T transition. To improve the existing census, we have searched ≈28,000 deg 2 using the Pan-STARRS1 and Wide-field Infrared Survey Explorer surveys for L/T transition dwarfs within 25 pc. We present 130 ultracool dwarf discoveries with estimated distances ≈9–130 pc, including 21 that were independently discovered by other authors and 3 that were previously identified as photometric candidates. Seventy-nine of our objects have near-IR spectral types of L6–T4.5, the most L/T transition dwarfs from any search to date, and we have increased the census of L9–T1.5 objects within 25 pc by over 50%. The color distribution of our discoveries provides further evidence for the “L/T gap,” a deficit of objects with (J − K) MKO  ≈ 0.0–0.5 mag in the L/T transition, and thus reinforces the idea that the transition from cloudy to clear photospheres occurs rapidly. Among our discoveries are 31 candidate binaries based on their low-resolution spectral features. Two of these candidates are common proper motion companions to nearby main sequence stars; if confirmed as binaries, these would be rare benchmark systems with the potential to stringently test ultracool evolutionary models. Our search also serendipitously identified 23 late-M and L dwarfs with spectroscopic signs of low gravity implying youth, including 10 with vl-g or int-g gravity classifications and another 13 with indications of low gravity whose spectral types or modest spectral signal-to-noise ratio do not allow us to assign formal classifications. Finally, we identify 10 candidate members of nearby young moving groups (YMG) with spectral types L7–T4.5, including three showing spectroscopic signs of low gravity. If confirmed, any of these would be among the coolest known YMG members and would

  16. Corrections and additions to CONTEMPT-LT computer codes for containment analysis

    International Nuclear Information System (INIS)

    Eerikaeinen, Lauri.

    1980-01-01

    The report presents a new version of CONTEMPT-LT/26 tainment code. The corrections and additions are applicable also to other CONTEMPT-LT versions. Thermodynamical background of corrections are shortly described, and in addition, some essential points which should be taken into account in the analysis of a pressure suppression containment have been pointed out. The results obtained by the corrected version have been compared to those calculated by the original program, and to the measured data in the Marviken containment experiment No 10. Finally, it has been indicated that for reliable pressure suppression analysis a wide ranging condensation model for air-steam mixture is necessary. (author)

  17. AutoCAD 2015 and AutoCAD LT 2015 bible

    CERN Document Server

    Finkelstein, Ellen

    2014-01-01

    The perfect reference for all AutoCAD users AutoCAD 2015 and AutoCAD LT 2015 Bible is the book you want to have close at hand to answer those day-to-day questions about this industry-leading software. Author and Autodesk University instructor Ellen Finkelstein guides readers through AutoCAD 2015 and AutoCAD LT 2015 with clear, easy-to-understand instruction and hands-on tutorials that allow even total beginners to create a design on their very first day. Although simple and fundamental enough to be used by those new to CAD, the book is so comprehensive that even Autodesk power u

  18. Investigation of Public Charging Infrastructure : Case study Gränby sportfält

    OpenAIRE

    Dahl, Emma; Hedström, Andreas; Lindgren, Anna

    2017-01-01

    The municipal company Sportfastigheter AB is currently renovating and developing Gränby sportfält, a sports field in Uppsala. Adjacent to the sports field, a parking lot for 700 vehicles is located, where Sportfastigheter AB is preparing to install charging points for electric vehicles (EVs) at some of the places. This bachelor thesis aims to investigate how a public charging solution should be modeled, with the parking lot at Gränby sportfält as a case study. The investigation involves estim...

  19. Characterization of LT-LiXO1-YNIYO2 electrodes for rechargeable lithium cells

    CSIR Research Space (South Africa)

    Gummow, RJ

    1993-12-01

    Full Text Available -spinel in character and that LT- Li0.4Co0.sNi0.102 is a defect spinel with spinel notation {Li0.s\\[:\\]0.2}sa \\[Co, 6Nio.2D0.2104. Electrochemical data.--The charge and discharge pro- files for the first four cycles of Li/LT-LiCoO2, Li... on the B sites of an A\\[B2104 spinel structure. The spinel phase is significantly more stable to lithium insertion/extraction reactions than the quasi-spinel phase. It is believed that by optimizing the processing conditions...

  20. Electronic structure of α-SrB4O7: experiment and theory

    International Nuclear Information System (INIS)

    Atuchin, V V; Kesler, V G; Zaitsev, A I; Molokeev, M S; Aleksandrovsky, A S; Kuzubov, A A; Ignatova, N Y

    2013-01-01

    The investigation of valence band structure and electronic parameters of constituent element core levels of α-SrB 4 O 7 has been carried out with x-ray photoemission spectroscopy. Optical-quality crystal α-SrB 4 O 7 has been grown by the Czochralski method. Detailed photoemission spectra of the element core levels have been recorded from the powder sample under excitation by nonmonochromatic Al Kα radiation (1486.6 eV). The band structure of α-SrB 4 O 7 has been calculated by ab initio methods and compared to XPS measurements. It has been found that the band structure of α-SrB 4 O 7 is weakly dependent on the Sr-related states. (paper)

  1. Heterogeneous free-surface profile of B4C polycrystal under shock compression

    International Nuclear Information System (INIS)

    Mashimo, T.; Uchino, M.

    1997-01-01

    Observations of the free-surface behavior under shock compression by the gapped-flat mirror method were performed on B 4 C and Si 3 N 4 ceramics to study their shock-yielding properties. Jagged profiles of the moving free-surface in the plastic region, with a special scale of about one mm and a maximum local displacement of a few 10s of μm, were observed for B 4 C polycrystals. Similar profiles for Si 3 N 4 polycrystals were smooth. Such profiles for B 4 C polycrystals were also observed in the elastic region. It is suggested that these observations reflect the heterogeneous nature of shock compression in solids, and further indicate that a macroscopic slip system plays an important role in the elastoplastic transition of B 4 C material under shock compression and decompression. copyright 1997 American Institute of Physics

  2. Eph-B4 regulates adaptive venous remodeling to improve arteriovenous fistula patency

    OpenAIRE

    Protack, Clinton D.; Foster, Trenton R.; Hashimoto, Takuya; Yamamoto, Kota; Lee, Monica Y.; Kraehling, Jan R.; Bai, Hualong; Hu, Haidi; Isaji, Toshihiko; Santana, Jeans M.; Wang, Mo; Sessa, William C.; Dardik, Alan

    2017-01-01

    Low rates of arteriovenous fistula (AVF) maturation prevent optimal fistula use for hemodialysis; however, the mechanism of venous remodeling in the fistula environment is not well understood. We hypothesized that the embryonic venous determinant Eph-B4 mediates AVF maturation. In human AVF and a mouse aortocaval fistula model, Eph-B4 protein expression increased in the fistula vein; expression of the arterial determinant Ephrin-B2 also increased. Stimulation of Eph-B-mediated signaling with ...

  3. Study of influence content of TiB2 by reaction in situ B4C and TiC in mechanical properties on B4C ceramics

    International Nuclear Information System (INIS)

    Coelho, M.L. Ramos; Bressiani, J.C.; Gomide, R.G.; Andrade, F.A. de

    2012-01-01

    The low density of ceramic materials promoted a change in research lines in the defense field. Research efforts and development directed to obtaining products of high density sintered of Al2O3, SiC and B4C, using different routes, both traditional as innovative, led to promising initial results, which justify the convergence of skills for the consolidation of research lines and the nationalization that sintered components of B4C with characteristics and properties compatible with the technical requirements established for the ballistic application. The low density of boron carbide (2.52 g/cm 3 ) gives in the final product a weight approximately 30% lower than armor made of alumina (3.96 g/cm 3 ). (author)

  4. Production of thermoluminescent dosemeters based on MgB4O7: Dy and MgB4O7: Tm

    International Nuclear Information System (INIS)

    Souza, Luiza Freire de; Souza, Divanizia N.

    2013-01-01

    The thermoluminescent dosimetry (TL) is a well-established technique for the detection of ionizing radiation in hospitals, clinics, and industrial establishments where there is the need to quantify the radiation. For this practice is require the use phosphors which are sensitive to radiation. Some phosphors are already commonly used in this practice, for example, TLD-100 (LiF: Mg, Ti), CaSO 4 :Tm and CaSO 4 :Dy. A compound that was most recently introduced in dosimetry and has many advantageous features to detect neutrons, electrons and gamma is the magnesium tetraborate (MgB 4 O 7 ), but the undoped material is not good for dosimetry, since signal does not show satisfactory thermoluminescence. The present work presents the analysis of the compound MgB 4 O 7 when doped with rare earth elements, thulium (Tm) and dysprosium (Dy). The production of MgB 4 O 7 : Dy and MgB 4 O 7 : Tm occurred under acidic conditions. Following the process of crystal growth, several tests were made on phosphors produced to verify the quality of materials as TL dosimeter. Initially, was made the identification of the crystalline phases found in the material, using the technique of X-ray diffractometry, and then were evaluated and compared the TL emission curves of the crystals with two different types of dopants, to this, the samples were irradiated with different radiation sources: 137 Cs (0,66 MeV), 60 Co (1.25 MeV) and X-rays (0.41 MeV) and based on the results was evaluated the energy dependence of phosphors. Another characteristic analyzed, was the decay of TL signal for the material (fading). The results show that the material can be an excellent TL dosimeter when doped with rare earth elements Dy and Tm. (author)

  5. Arcing at B4C-covered limiters exposed to a SOL-plasma

    International Nuclear Information System (INIS)

    Laux, M.; Schneider, W.; Wienhold, P.; Juettner, B.; Huber, A.; Balden, M.; Linke, J.; Kostial, H.; Mayer, M.; Rubel, M.; Herrmann, A.; Pospieszczyk, A.; Jachmich, S.; Schweer, B.; Hildebrandt, D.; Bolt, H.

    2003-01-01

    Plasma sprayed B 4 C-layers considered as wall coatings for the W7X stellarator have been studied during and after exposure to TEXTOR and after arcing experiments in vacuum. Arcing through the B 4 C layer occurred favoured by high power fluxes and not restricted to less stable phases. But this arcing implies an especially noisy scrape-off layer (SOL). Instead of moving retrograde in the external magnetic field, the arc spot on the B 4 C-layer sticks to the same location for its whole lifetime. Consequently, the arc erodes the entire B 4 C layer, finally burning down to the Cu substrate. In the neighbourhood of craters the surface contains Cu originating from those craters. This material, hauled to the surface by the arc, is subject to subsequent erosion, transport, and redeposition by the SOL-plasma. The behaviour of arcs on B 4 C is most probably caused by the peculiar temperature dependences of the electrical and heat conductivity of B 4 C

  6. Chemical interaction of B4C, B, and C with Mo/Si layered structures

    International Nuclear Information System (INIS)

    Rooij-Lohmann, V. I. T. A. de; Veldhuizen, L. W.; Zoethout, E.; Yakshin, A. E.; Kruijs, R. W. E. van de; Thijsse, B. J.; Gorgoi, M.; Schaefers, F.; Bijkerk, F.

    2010-01-01

    To enhance the thermal stability, B 4 C diffusion barrier layers are often added to Mo/Si multilayer structures for extreme ultraviolet optics. Knowledge about the chemical interaction between B 4 C and Mo or Si, however is largely lacking. Therefore, the chemical processes during annealing up to 600 deg. C of a Mo/B 4 C/Si layered structure have been investigated in situ with hard x-ray photoelectron spectroscopy and ex situ with depth profiling x-ray photoelectron spectroscopy. Mo/B/Si and Mo/C/Si structures have also been analyzed as reference systems. The chemical processes in these systems have been identified, with two stages being distinguished. In the first stage, B and C diffuse and react predominantly with Mo. MoSi x forms in the second stage. If the diffusion barrier consists of C or B 4 C, a compound forms that is stable up to the maximum probed temperature and annealing time. We suggest that the diffusion barrier function of B 4 C interlayers as reported in literature can be caused by the stability of the formed compound, rather than by the stability of B 4 C itself.

  7. [Survival properties of ETEC surface-displayed K88ac-LT(B) on Lactobacillus casei].

    Science.gov (United States)

    Wei, Chunhua; Liu, Jiankui; Hou, Xilin; Wang, Guihua; Yu, Liyun

    2009-01-01

    K88ac-LT(B) gene derived from pQE30-K88ac-LT(B) was cloned into the expression vector pLA and then the recombinant vector was transformed into the competent cells Lactobacillus casei 525. The recombinant bacteria were grown at 37 degrees C, in MRS broth. Western blotting analysis with rabbit-anti-K88ac-LT(B) polyclonal serum indicated that the recombinant protein reacted with the specific antibodies. The results showed that the molecular weight of the recombinant protein was about 71.2 kD. The K88ac-LT(B) fusion protein on the cell surface was confirmed by immunofluorescence mciroscopy and flow cytometric analysis. In addition, the survival of recombinant Lactobacillus casei 525 was studied in imitative gastrointestinal environments such as artificial gastro fluid (pH 1.5-5.5), artificial intestinal fluid, bile(0.3-3.0 g/L). The results indicated that the recombinant strain survived well in artificial gastric fluids at pH 2.5-4.5 in 5 h. The recombinant Lactobacillus casei 525 could slowly grow in the artificial intestinal fluid for different time, and could survive in 0.3% bile.

  8. Airpower Leadership on the Front Line: Lt Gen George H. Brett and Combat Command

    Science.gov (United States)

    2006-09-01

    was assigned the additional duty of unit photographer and historian, bequeathing a photo album depicting his adventures to his oldest daughter.10 Lt...his fellow residents with piano music when the men were off duty.21 At the close of the war Brett was a temporary major and listed among officers who

  9. Ion heating at the disruptive instability in the LT-3 Tokamak

    International Nuclear Information System (INIS)

    Bell, M.G.; Hutchinson, I.H.

    1976-01-01

    Measurements of the ion temperature and the toroidal current density and electric field during the disruptive instability in LT-3 are presented. Rapid ion heating and strong current inhibition have been observed. Fluctuation measurements suggest that these effects may be attributable to the excitation of ion cyclotron drift waves in the plasma

  10. Rotavirus 2/6 Viruslike Particles Administered Intranasally with Cholera Toxin, Escherichia coli Heat-Labile Toxin (LT), and LT-R192G Induce Protection from Rotavirus Challenge

    Science.gov (United States)

    O’Neal, Christine M.; Clements, John D.; Estes, Mary K.; Conner, Margaret E.

    1998-01-01

    We have shown that rotavirus 2/6 viruslike particles composed of proteins VP2 and VP6 (2/6-VLPs) administered to mice intranasally with cholera toxin (CT) induced protection from rotavirus challenge, as measured by virus shedding. Since it is unclear if CT will be approved for human use, we evaluated the adjuvanticity of Escherichia coli heat-labile toxin (LT) and LT-R192G. Mice were inoculated intranasally with 10 μg of 2/6-VLPs combined with CT, LT, or LT-R192G. All three adjuvants induced equivalent geometric mean titers of rotavirus-specific serum antibody and intestinal immunoglobulin G (IgG). Mice inoculated with 2/6-VLPs with LT produced significantly higher titers of intestinal IgA than mice given CT as the adjuvant. All mice inoculated with 2/6-VLPs mixed with LT and LT-R192G were totally protected (100%) from rotavirus challenge, while mice inoculated with 2/6-VLPs mixed with CT showed a mean 91% protection from challenge. The availability of a safe, effective mucosal adjuvant such as LT-R192G will increase the practicality of administering recombinant vaccines mucosally. PMID:9525668

  11. The B4 school check behaviour measures: findings from the Hawke's Bay evaluation.

    Science.gov (United States)

    Hedley, Cath; Thompson, Shona; Morris Matthews, Kay; Pentecost, Mandy; Wivell, Judy; Frost, Ariana Stockdale; Morris, Helen

    2012-11-01

    The Before (B4) School Check is a free health and development check delivered by specifically trained nurses to four year old children throughout New Zealand, aimed to identify and address any health, behavioural, social or developmental concerns that could affect a child's ability to get the most benefit from school. Reported here are the results of an evaluation of the B4 School Checks in Hawke's Bay, focusing specifically on children assessed at the 84 School Check with behaviour issues as determined by the Strengths and Difficulties Questionnaire (SDQ). Health Hawke's Bay (HHB) records were reviewed to understand the number and demographics of the children assessed with behaviour issues at the B4 School Checks up to 31 August 2011, and the interventions to which they were referred. Telephone Interviews were conducted with 36 parents/caregivers of these children to address the questions, what difference did the B4 School Check make to children assessed with behaviour issues and what aspects of the B4 School Check delivery contributed to successful outcomes for these children? Results showed that child behaviour issues in Hawke's Bay were identified in more boys than girls and concentrated in more deprived families. Māori children were represented in numbers disproportional to the regional population. The majority of referrals for child behaviour directed parents/caregivers to non-governmental organisations for family support and parenting programmes. Thematic analysis was applied to the qualitative data derived from the interviews with parents/caregivers and results indicated high levels of satisfaction with the B4 School Check for behaviour and the referred outcomes. Implications for nursing practice arise from these findings in that they identify factors which contribute to what does and does not work well for achieving successful outcomes from the B4 School Check for behaviour.

  12. Role of the route of leukotrienes in an experimental model of oral mucositis induced by 5-fluorouracil 1.

    Science.gov (United States)

    Silva, Viviane Carvalho da; Leitão, Renata Ferreira de Carvalho; Brito, Gerly Anne de Castro; Martins, Conceição da Silva; Freire, Gildenio Estevam; Aragão, Karoline Saboia; Wanderley, Carlos Wagner de Souza; Freitas, Marcos Rabelo de

    2017-09-01

    To investigate the participation of cysteinyl leukotrienes in the pathophysiology of oral mucositis. Oral mucositis was induced in hamsters using 5-fluorouracil (5-FU; 60 and 40 mg/kg; i.p., on days 1 and 2, respectively, and with excoriations in jugal mucosa on day 4). Montelukast (10, 20, or 40 mg/kg/d; gavage), MK886 (3 mg/kg/d, i.p.), or saline or celecoxib (7.5 mg/kg/d; i.p.) was administered 1 h prior to 5-FU and daily, until the fourth (MK886) or tenth day, when the animals were euthanized and their jugal mucosa was collected for macroscopic, histopathological, and immunohistochemical evaluation. Neither montelukast nor MK-886 prevented the oral mucositis induced by 5-FU, as observed by histopathological evaluation. In addition, we did not find significant differences in the expression of inducible nitric oxide synthase-2, cyclooxygenase-2, or interleukin (IL)-1β between the experimental and control groups. However, we did observe a significant decrease in tumor necrosis factor (TNF)-α expression for all doses of montelukast; we also observed a significant decrease in IL-10 with 40 mg/kg/d and MK 886. Cysteinyl leukotrienes do not play an important role in experimental oral mucositis induced by 5-FU. There is a modulating action specifically on TNF-α.

  13. Leukotriene signaling in the extinct human subspecies Homo denisovan and Homo neanderthalensis. Structural and functional comparison with Homo sapiens.

    Science.gov (United States)

    Adel, Susan; Kakularam, Kumar Reddy; Horn, Thomas; Reddanna, Pallu; Kuhn, Hartmut; Heydeck, Dagmar

    2015-01-01

    Mammalian lipoxygenases (LOXs) have been implicated in cell differentiation and in the biosynthesis of pro- and anti-inflammatory lipid mediators. The initial draft sequence of the Homo neanderthalensis genome (coverage of 1.3-fold) suggested defective leukotriene signaling in this archaic human subspecies since expression of essential proteins appeared to be corrupted. Meanwhile high quality genomic sequence data became available for two extinct human subspecies (H. neanderthalensis, Homo denisovan) and completion of the human 1000 genome project provided a comprehensive database characterizing the genetic variability of the human genome. For this study we extracted the nucleotide sequences of selected eicosanoid relevant genes (ALOX5, ALOX15, ALOX12, ALOX15B, ALOX12B, ALOXE3, COX1, COX2, LTA4H, LTC4S, ALOX5AP, CYSLTR1, CYSLTR2, BLTR1, BLTR2) from the corresponding databases. Comparison of the deduced amino acid sequences in connection with site-directed mutagenesis studies and structural modeling suggested that the major enzymes and receptors of leukotriene signaling as well as the two cyclooxygenase isoforms were fully functional in these two extinct human subspecies. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Urinary Leukotriene E4 Is Associated with Renal Function but Not with Endothelial Function in Type 2 Diabetes

    Directory of Open Access Journals (Sweden)

    Arnar Rafnsson

    2013-01-01

    Full Text Available Leukotrienes are inflammatory and vasoactive mediators implicated in endothelium-dependent relaxations and atherosclerosis. Urinary leukotriene E4 (U-LTE4 is a validated disease marker of asthma and increases also in diabetes and acute coronary syndromes. The aim of the present study was to evaluate the association of U-LTE4 and CRP with endothelial function. Urine samples were obtained from 30 subjects (80% males; median age 65 with type 2 diabetes of at least two years duration and a median glomerular filtration rate (eGFR of 71 (14–129 mL/min. Reactive hyperemia index (RHI was used as a measure of microvascular endothelial function, whereas macrovascular endothelial function was determined be means of flow-mediated dilatation of the brachial artery (FMD. Decreased renal function was associated with lower concentrations of U-LTE4. In addition, U-LTE4 was correlated with serum creatinine (R=−0.572; P=0.001 and eGFR (R=0.517; P=0.0036. A stepwise multiple linear regression analysis identified eGFR as an independent predictor of U-LTE4 concentrations. In conclusion, the present results did not establish an association of U-LTE4 with endothelial dysfunction. However, eGFR was an independent predictor of U-LTE4, but not CRP, in this cohort, suggesting that GFR should be considered in biomarker studies of U-LTE4.

  15. Effect of leukotriene receptor antagonists on vascular permeability during endotoxic shock

    International Nuclear Information System (INIS)

    Cook, J.A.; Li, E.J.; Spicer, K.M.; Wise, W.C.; Halushka, P.V.

    1990-01-01

    Evidence has accumulated that sulfidopeptide leukotrienes are significant pathogenic mediators of certain hematologic and hemodynamic sequelae of endotoxic shock. In the present study, the effects of a selective LTD4/E4 receptor antagonist, LY171883 (LY), or a selective LTD4 receptor antagonist, SKF-104353 (SKF), were assessed on splanchnic and pulmonary localization of 99mTechnetium-labeled human serum albumin (99mTc-HSA) in acute endotoxic shock in the rat. Dynamic gamma camera imaging of heart (H), midabdominal (GI), and lung regions of interest generated time activity curves for baseline and at 5-35 min after Salmonella enteritidis endotoxin (10 mg/kg, i.v.). Slopes of GI/H and lung/H activity (permeability index, GI/H or lung/H X 10(-3)/min) provided indices of intestinal and lung localization. Rats received LY (30 mg/kg, i.v.), LY vehicle (LY Veh), SKF (10 mg/kg), or SKF vehicle (SK Veh) 10 min prior to endotoxin or endotoxin vehicle. In rats receiving the LY Veh and endotoxin (n = 8) or SKF Veh and endotoxin (n = 12), the splanchnic permeability indices to 99mTc-HSA were increased 11.2-fold and 5.1-fold, respectively (P less than 0.05) compared to vehicle control groups not given endotoxin (n = 5). Pulmonary permeability index for 99mTc-HSA was increased (P less than 0.05) to a lesser extent (3.2-fold) by endotoxin compared to vehicle controls. Pretreatment with SKF reduced the mesenteric permeability index to control levels (P less than 0.05) during the 5-35 min time interval post-endotoxin. LY reduced the mesenteric permeability index by 70%. Pulmonary relative permeability to 99mTc-HSA was not affected by LY pretreatment. Both splanchnic and lung relative permeability to the isotope was transient; at 135-225 min post-endotoxin, splanchnic localization of 99mTc-HSA (n = 4) was not significantly different from vehicle controls in these vascular beds

  16. Wetting of B4C, TiC and graphite substrates by molten Mg

    International Nuclear Information System (INIS)

    Zhang Dan; Shen Ping; Shi Laixin; Jiang Qichuan

    2011-01-01

    Highlights: → The wettability of TiC, B4C and C by molten Mg was determined using an improved sessile drop method. → A new method to evaluate the wetting behavior coupled with evaporation and reaction was proposed. → The bonding characteristics in the Mg/B4C, Mg/TiC and Mg/graphite systems were evaluated. - Abstract: The isotherm wetting of B 4 C, TiC and graphite substrates by molten Mg was studied in a flowing Ar atmosphere at 973-1173 K using an improved sessile drop method. The initial contact angles are in the ranges of 95-87 deg., 74-60 deg. and 142-124 deg., respectively, moderately depending on the temperature. All the systems are non-reactive in nature; however, the presence of impurity of free boron at the B 4 C surface gave rise to the chemical reaction with molten Mg and thus promoted the wettability to a certain degree. A new method was proposed to evaluate the wetting behavior coupled with evaporation and chemical reaction. Furthermore, based on the comparison of the work of adhesion and cohesion, the bonding in the Mg/B 4 C and Mg/TiC systems is presumably mainly chemical while that in the Mg/graphite system is physical.

  17. Interlayer growth in Mo/B4C multilayered structures upon thermal annealing

    International Nuclear Information System (INIS)

    Nyabero, S. L.; Kruijs, R. W. E. van de; Yakshin, A. E.; Zoethout, E.; Bosgra, J.; Loch, R. A.; Blanckenhagen, G. von; Bijkerk, F.

    2013-01-01

    Both multilayer period thickness expansion and compaction were observed in Mo/B 4 C multilayers upon annealing, and the physical causes for this were explored in detail. Using in situ time-dependent grazing incidence X-ray reflectometry, period changes down to picometer-scale were resolved. It was shown that the changes depend on the thickness of the B 4 C layers, annealing temperature, and annealing time. Although strong stress relaxation during annealing was observed, it was excluded as a cause for period expansion. Auger electron spectroscopy and wide angle X-ray diffraction measurements revealed the growth of interlayers, with associated period changes influenced by the supply of B and C atoms to the growing compound interlayers. For multilayers with a Mo thickness of 3 nm, two regimes were recognized, depending on the deposited B 4 C thickness: in multilayers with B 4 C ≤ 1.5 nm, the supply of additional Mo into the already formed MoB x C y interlayer was dominant and led to densification, resulting in period compaction. For multilayers with B 4 C ≥ 2 nm, the B and C enrichment of interlayers formed low density compounds and yielded period expansion.

  18. Wear behaviour of plasma-sprayed AlSi/B4C composite coatings

    International Nuclear Information System (INIS)

    Sarikaya, Ozkan; Anik, Selahaddin; Celik, Erdal; Okumus, S. Cem; Aslanlar, Salim

    2007-01-01

    This paper describes the wear behaviour of AlSi/B 4 C composite coatings with 0-25 wt% B 4 C particles for diesel engine motors. These coatings were successfully fabricated on AlSi substrates using an atmospheric plasma spray technique. The produced samples were characterized by means of an optical microscope, scanning electron microscope and microhardness tester. The obtained results pointed out that an increase of B 4 C particles in AlSi coatings was caused on the rising of the microhardness values and the decrease of the thermal expansion coefficient of the coatings. The friction and wear experiments were performed under dry conditions using a ball-on-dics configuration against WC/Co counter material for different loads. It was concluded that wear resistance of the coatings produced using B 4 C powders is greatly improved compared with the substrate material. The highest wear resistance of the coatings were also determined in the 20% B 4 C coating

  19. Advancements in the treatment of hypothyroidism with L-T4 liquid formulation or soft gel capsule: an update.

    Science.gov (United States)

    Fallahi, Poupak; Ferrari, Silvia Martina; Ruffilli, Ilaria; Ragusa, Francesca; Biricotti, Marco; Materazzi, Gabriele; Miccoli, Paolo; Antonelli, Alessandro

    2017-05-01

    The most recent advance concerning levothyroxine (L-T4) therapy is the development of novel oral formulations: the liquid preparation, and the soft gel capsule. Areas covered: This review evaluates the most recent clinical studies about these new formulations. The liquid formulation has been shown to overcome: the food and beverages intereference with L-T4 tablets absorption, caused by food or coffee at breakfast; malabsorption induced by the increased gastric pH, resulting from atrophic gastritis, or due to proton-pump inhibitors; and malabsorption after bariatric surgery. The use of liquid L-T4 has been studied also in pregnancy, newborns and infants, suggesting a better bioequivalence than tablets. Finally, liquid L-T4 is more active than tablets in the control of thyroid-stimulating hormone (TSH) in hypothyroid patients without malabsorption, drug interference, or gastric disorders, leading to a hypothesized higher absorption of liquid L-T4 also in these patients. Few studies have evaluated soft gel L-T4 with promising results in patients with malabsorption related to coffee or gastritis. Expert opinion: Liquid L-T4 (and soft gel capsules) are more active than the tablet L-T4 in the control of TSH in hypothyroid patients with gastric disorders, malabsorption, or drug interference, but also in patients without absorption disorders.

  20. LT-CFB. Further development and commercialization. Final report. [Low Temperature Circulating Fluid Bed gasifier]; LT-CFB. Videreudvikling og kommercialisering. Slutrapport

    Energy Technology Data Exchange (ETDEWEB)

    Stoholm, P. [DFBT, Roskilde (Denmark); Birk Henriksen, U.; Ahrentfeldt, J. [Technical Univ. of Denmark. DTU Chemical Engineering, CHEC Research Centre, Roskilde (Denmark); Cramer, J.; Dietrich, J.; Christiansen, Knud [FORCE Technology, Kgs. Lyngby (Denmark); Krogh, J. [Anhydro A/S, Soeborg (Denmark)

    2011-12-15

    The starting point for the project was the good results achieved in a previous project, in which a series of experiments were carried out with a 500 kW pilot plant at teh Technical University of Denmark. The main task was then to find a way forward towards further scale-up, demonstration and commercialization. The project's partners chose to study three possible sites for demonstration. However, during the project both framework conditions as well as DONG Energy's strategy changed, which resulted in the company taking over the LT-CFB technology in December 2009. As a first step a 6 MW demonstration plant will now be set up at the Asnaes power plant expected to start in spring 2011. The project has also been buit a new mobile 100 kW LT-CFB plant for the further optimization of the process and for short-term trials of new fuels. At the new plant a number of successful trials were performed with straw and residual fibers. Furthermore, it is experimentally demonstrated that it is possible to cool the tar-containing gas to approx. 300 degrees C and purify the gas in a bag filter, so it can be used in natural gas-fired power plant boilers. With the new mobile system, it will now be easier to perform experiments with a number of new fuels such as unsorted municipal waste, bone meal and dried sewage sludge. (LN)

  1. Dosimetric properties of Li2 B4 O7: Tm pellets

    International Nuclear Information System (INIS)

    Rzyski, B.M.; Morato, S.P.

    1987-10-01

    Pellets produced out of thulium doped lithium tetraborate, (Li 2 B 4 O 7 :Tm), for thermoluminescent, (TL), dosimetry present low sensibility to environment conditions. Humidity, ambiet temperature, fading and handling during TL reading have almost no influence on the TL properties of the pellets prepared according the receipt given in this paper. The structure of the TL glow curve for the irradiated Li 2 B 4 O 7 : Tm pellet is rather simple and the TL response is linear in the range of 3x10 -4 to 7x10 2 Gy. The dosimetric properties of Li 2 B 4 O 7 : Tm in pellet form makes it a competitor with other TL phosphors. (author) [pt

  2. Interface interaction in the B4C/(Fe-B-C) system

    International Nuclear Information System (INIS)

    Aizenshtein, M.; Mizrahi, I.; Froumin, N.; Hayun, S.; Dariel, M.P.; Frage, N.

    2008-01-01

    The wetting behavior in the B 4 C/(Fe-C-B) system was investigated in order to clarify the role of Fe additions on the sinterability of B 4 C. Iron and its alloys with C and B react with the boron carbide substrate and form a reaction zone consisting of a fine mixture of FeB and graphite. The apparent contact angles are relatively low for the alloys with a moderate concentration of the boron and carbon and allow liquid phase sintering to occur in the B 4 C-Fe mixtures. A dilatometric study of the sintering kinetics confirms that liquid phase sintering actually takes place and leads to improved mass transfer. A thermodynamic analysis of the ternary Fe-B-C system allows accounting for the experimental observations

  3. MD421: Electron cloud studies on 25 ns beam variants (BCMS, 8b+4e)

    CERN Document Server

    Iadarola, Giovanni; Belli, Eleonora; Carver, Lee Robert; Dijkstal, Philipp; Li, Kevin Shing Bruce; Mether, Lotta; Romano, Annalisa; Rumolo, Giovanni; CERN. Geneva. ATS Department

    2017-01-01

    This note describes a Machine Development session performed with the main goal of studying the e-cloud mitigation that can be obtained by injecting mixed trains of 8b+4e beam type and trains having the standard 25 ns structure. Additionally, in the course of the MD, the pure 8b+4e beam was also checked to be stable when injected with low chromaticity and octupole current settings. Subsequently, the operational BCMS 25 ns beam was also injected with the 8b+4e settings and found to be unstable. The operational settings for injection were re-found by gradually increasing the chromaticity and octupole knobs until all the bunches of the injected beam could remain stable after injection.

  4. Radiation defects in SrB4O7:Eu2+ crystals

    International Nuclear Information System (INIS)

    Yavetskiy, R.P.; Dolzhenkova, E.F.; Tolmachev, A.V.; Parkhomenko, S.V.; Baumer, V.N.; Prosvirnin, A.L.

    2007-01-01

    Radiation-induced defects in SrB 4 O 7 :Eu 2+ (0.033 at.%) single crystal irradiated with γ and X-ray quanta has been studied. The induced optical absorption in the 400-700 nm region has been ascribed to F + centers. The Eu 2+ ions have been shown to act simultaneously as traps and as radiative recombination centers of charge carriers. Basing on the thermally stimulated luminescence (TSL), optical absorption and photoluminescence studies of SrB 4 O 7 :Eu 2+ crystals, a TSL mechanism has been proposed associated with the decay of F + centers being in non-equivalent crystallographic positions followed by radiative recombination of charge carriers on europium ions. Various positions of localization of the radiation-induced defects in the SrB 4 O 7 crystal structure have been discussed

  5. Short syntheses of enantiopure calystegine B-2, B-3, and B-4

    DEFF Research Database (Denmark)

    Skaanderup, Philip Robert; Madsen, Robert

    2001-01-01

    Calystegine B-2 B-3, and B-4 have been prepared in 5 steps from the benzyl protected methyl 6-iodoglycopyranosides of glucose, galactose and mannose, respectively, by using a zinc-mediated domino reaction followed by ring-closing olefin metathesis as the key steps.......Calystegine B-2 B-3, and B-4 have been prepared in 5 steps from the benzyl protected methyl 6-iodoglycopyranosides of glucose, galactose and mannose, respectively, by using a zinc-mediated domino reaction followed by ring-closing olefin metathesis as the key steps....

  6. Effect of sintering temperature on the densification of B4C pellets

    International Nuclear Information System (INIS)

    Gomide, R.G.; Durazzo, M.; Riella, H.G.

    1990-01-01

    Boron is largely used in several types of nuclear reactors control and safety systems. In the majority of these applications sintered boron carbide pellets are used. Near stoichiometric B 4 C hardly densifies during pressureless sintering. As a starting point of an overall program to produce > 70% TD B 4 C pellets pressing parameters have been studied for further study of the influence of sintering temperature in the densification of this ceramic material. Dilatometric analyses show that sintering starts at 1760 0 C for the F 1200 ESK - type boron carbide powders. Moreover, the sintering experiments show that up to 92% TD pellets can be obtained. (author) [pt

  7. Tetrahedral 1B4Sb nanoclusters in GaP:(B, Sb)

    Energy Technology Data Exchange (ETDEWEB)

    Elyukhin, V A, E-mail: elyukhin@cinvestav.m [Departamento de Ingenieria Electrica-SEES, CINVESTAV-IPN, Avenida IPN 2508, Col. San Pedro Zacatenco, C. P. 07360, Mexico, D. F. (Mexico)

    2009-05-01

    Self-assembling conditions of 1B4Sb tetrahedral nanoclusters in GaP doped with boron and Sb isoelectronic impurities are represented in the ultradilute and dilute limits of the boron and Sb contents, respectively. The fulfilled estimates demonstrated the preferential complete or almost complete allocation of boron atoms in 1B4Sb nanoclusters at temperatures of 500 {sup 0}C and 900 {sup 0}C, respectively. The significant decrease of the sum of the free energies of the constituent compounds is the main origin of self-assembling. The reduction of the strain energy is the additional cause of this phenomenon.

  8. Application of full factorial design to study the tribological properties of AA6061-B4C and AA6061-B4C-MoS2 composites

    Directory of Open Access Journals (Sweden)

    Monikandan V. V.

    2018-03-01

    Full Text Available This study statistically analyzes the tribological properties of AA6061-10 wt. % B4C mono composite and AA6061-10 wt.% B4C-7.5 wt. % MoS2 hybrid composite. The tribological behavior of the composites was studied at atmospheric conditions using a pin-on-disk tribo-tester. The tribological experiments were conducted as per the full factorial design (FFD experimental scheme. The ANOVA analysis of the wear rate revealed that the three factors, A (MoS2 particles addition, B (applied load, and D (sliding distance presented the physical and statistical significance on the wear rate. The ANOVA analysis of the friction coefficient revealed that the factors B (applied load and C (sliding speed and interaction AB (interaction of MoS2 particles addition and applied load presented the physical and statistical significance on the friction coefficient. It is observed from the main effects plots of the wear rate and friction coefficient that the increase in the levels of factors B (applied load and D (sliding distance increased the wear rate and friction coefficient. However, the wear rate and friction coefficient decreased with the increase in the level of factor A (MoS2 particles addition.

  9. 76 FR 25259 - Airworthiness Directives; Airbus Model A300 B4-600, A300 B4-600R, and A300 F4-600R Series...

    Science.gov (United States)

    2011-05-04

    ... Airworthiness Directives; Airbus Model A300 B4-600, A300 B4-600R, and A300 F4-600R Series Airplanes, and Model...-605R, B4-622R, F4-605R, F4-622R, and C4-605R Variant F airplanes; and Model A310-203, -204, -221, -222...

  10. 76 FR 47430 - Airworthiness Directives; Airbus Model A300 B4-600, A300 B4-600R, and A300 F4-600R Series...

    Science.gov (United States)

    2011-08-05

    ... Airworthiness Directives; Airbus Model A300 B4-600, A300 B4-600R, and A300 F4-600R Series Airplanes, and Model..., B4-622R, F4-605R, F4-622R, and C4-605R Variant F airplanes; and Model A310-203, -204, -221, -222...

  11. Novel UEP LT Coding Scheme with Feedback Based on Different Degree Distributions

    Directory of Open Access Journals (Sweden)

    Li Ya-Fang

    2016-01-01

    Full Text Available Traditional unequal error protection (UEP schemes have some limitations and problems, such as the poor UEP performance of high priority data and the seriously sacrifice of low priority data in decoding property. Based on the reasonable applications of different degree distributions in LT codes, this paper puts forward a novel UEP LT coding scheme with a simple feedback to compile these data packets separately. Simulation results show that the proposed scheme can effectively protect high priority data, and improve the transmission efficiency of low priority data from 2.9% to 22.3%. Furthermore, it is fairly suitable to apply this novel scheme to multicast and broadcast environments since only a simple feedback introduced.

  12. The Akashi Kaikyo Bridge and the Storebælt Bridge

    DEFF Research Database (Denmark)

    Gimsing, Niels Jørgen

    1999-01-01

    With the completion of the Akashi Kaikyo Bridge and the Storebælt East Bridge the development of the suspension bridge technology in the 20th century has manifested itself in two impressive structures. With the present echnology may bridges of similar (and also more modest) dimensions...... will undoubtedly be built far into the next century. For bridges going beyond the spans of existing bridges it is, however, likely that new concepts will be developed....

  13. 75 FR 44264 - Federal Management Regulation; FMR Bulletin PBS-2010-B4; Redesignation of Federal Building

    Science.gov (United States)

    2010-07-28

    ... Management Regulation; FMR Bulletin PBS-2010-B4; Redesignation of Federal Building AGENCY: Public Buildings... announces the redesignation of a Federal building. DATES: Expiration Date: This bulletin expires December 31, 2010. However, the building redesignation announced by this bulletin will remain in effect until...

  14. 26 CFR 1.851-3 - Rules applicable to section 851(b)(4).

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 9 2010-04-01 2010-04-01 false Rules applicable to section 851(b)(4). 1.851-3 Section 1.851-3 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES Regulated Investment Companies and Real Estate Investment Trusts § 1.851...

  15. The antagonistic effect of Banana bunchy top virus multifunctional protein B4 against Fusarium oxysporum.

    Science.gov (United States)

    Zhuang, Jun; Coates, Christopher J; Mao, Qianzhuo; Wu, Zujian; Xie, Lianhui

    2016-06-01

    The viral-induced banana bunchy top disease and the fungal-induced banana blight are two major causes of concern for industrial scale production of bananas. Banana blight is particularly troublesome, affecting ∼80% of crops worldwide. Strict guidelines and protocols are in place in order to ameliorate the effects of this devastating disease, yet little success has been achieved. From the data presented here, we have found that Banana bunchy top virus (BBTV)-infected bananas are more resistant to Fusarium oxysporum f. sp. cubense (Foc). BBTV appears to be antagonistic towards Foc, thus improving the survivability of plants against blight. The BBTV suppressor of RNA silencing, namely protein B4, displays fungicidal properties in vitro. Furthermore, transgenic tomatoes expressing green fluorescent protein (GFP)-tagged protein B4 demonstrate enhanced resistance to F. oxysporum f. sp. lycopersici (Fol). Differential gene expression analysis indicates that increased numbers of photogenesis-related gene transcripts are present in dark-green leaves of B4-GFP-modified tomato plants relative to those found in WT plants. Conversely, the transcript abundance of immunity-related genes is substantially lower in transgenic tomatoes compared with WT plants, suggesting that plant defences may be influenced by protein B4. This viral-fungal interaction provides new insights into microbial community dynamics within a single host and has potential commercial value for the breeding of transgenic resistance to Fusarium-related blight/wilt. © 2016 BSPP AND JOHN WILEY & SONS LTD.

  16. Dosimetry characteristics of thermoluminescent Li2B4O7:Cu phosphor

    International Nuclear Information System (INIS)

    Lakshmanan, A.R.; Chandra, B.; Bhatt, R.C.

    1981-01-01

    Preliminary investigations on the radiation dosimetry characteristics of Li 2 B 4 O 7 :Cu TLD phosphor are described. The major TL peak in this phosphor occurs at 230 0 C and its TL sensitivity to gamma radiation is two to three times higher than that of LiF TLD-100. The gamma dose Vs TL response of this peak is linear (within +- 20%) in the dose range 0.3 mGy-3x10 2 Gy above which saturation sets in. Its TL response for 30 keV X-rays is about 20% lower than that for 60 Coγ-rays. On annealing at 300 0 C, the phosphor gets slightly discoloured (brownish). This results in the reduction of the TL sensitivity by about 20 - 25%. The phosphor does not exhibit either sensitization or damage even after a gamma dose of 10 3 Gy. The TL emission spectrum has a broad peak at 360 nm. The intrinsic TL sensitivity of virgin Li 2 B 4 O 7 :Cu to 253.7 nm UV radiation is nearly 50 times higher than that of CaSO 4 :Dy. The post-irradiation fading in Li 2 B 4 O 7 :Cu at ambient temperature and humidity conditions is, however, less than 10% in 17 days. These characteristics indicate that Li 2 B 4 O 7 :Cu is a promising phosphor for ionizing as well as UV radiation dosimetry. (author)

  17. Gaseous swelling of B4C and UO2 fuel: similarities and differences

    International Nuclear Information System (INIS)

    Evdokimov, I.; Khoruzhii, O.; Kourtchatov, S.; Likhanskii, V.; Matweev, L.

    2001-01-01

    A major factor limiting the resource of control rods (CRs) for WWER-1000 reactors is their radiation damage. Radiation induced embrittlement of the CRs cladding, core swelling and gaseous internal pressure in CRs result in mechanical core-cladding interaction. This work is devoted to the physical analysis of processes that control the structural changes in neutron absorber elements with B 4 C under irradiation in water reactors. Particularly, the analysis of mechanisms of the helium porosity formation in B 4 C is undertaken. In view of the deficiency of experimental data on the subject, a fruitful approach to the problem is a comparative analysis of the swelling mechanisms in B 4 C absorber and UO 2 fuel. Using this similarity a phenomenological model of fission gas behavior in boron carbide is proposed. The model predictions for radial profile of 10 B burnup under influence of thermal and epithermal neutrons are compared with experimental results. The main results show that despite the external similarity of the process of fission gas accumulation in UO 2 and in B 4 C, phenomenology of gaseous swelling is much different for the fuel and the CR core. The reason for that difference is the distinction of physical conditions in irradiated fuel and CR core

  18. Nitridation and contrast of B4C/La interfaces and X-ray multilayer optics

    NARCIS (Netherlands)

    Tsarfati, T.; van de Kruijs, Robbert Wilhelmus Elisabeth; Zoethout, E.; Bijkerk, Frederik

    2010-01-01

    Chemical diffusion and interlayer formation in thin layers and at interfaces is of increasing influence in nanoscopic devices such as nano-electronics, magneto-optical storage and multilayer X-ray optics. We show that with the nitridation of reactive B4C/La interfaces, both the chemical and optical

  19. 77 FR 73302 - Extension of Dates for Certain Requirements and Amendment of Form 19b-4

    Science.gov (United States)

    2012-12-10

    ...-4 contained in the Adopting Release provide that, among other things, after December 10, 2012... require, among other things, DCAs for which the Commission is the supervisory agency to submit Advance..., ``Signature and Filing of the Completed Form,'' of the General Instructions for Form 19b-4 to require DCAs for...

  20. Grazing incidence Fe-line telescopes using W/B4C multilayers

    DEFF Research Database (Denmark)

    Joensen, K. D.; Gorenstein, P.; Christensen, Finn Erland

    1995-01-01

    The loss of throughput observed at higher energies for traditional grazing-incidence X-ray telescopes coated with high-Z elements can be partly countered by employing multilayers on the outermost reflectors. Using 8-keV reflectivity data from a periodic W/B4C multilayer, the expected performance...

  1. Dosimetric characteristics of Li2B4O7:Cu,Ag,P solid TL detectors

    International Nuclear Information System (INIS)

    Proki, M.

    2002-01-01

    The main dosimetric characteristics are presented of newly prepared tissue-equivalent, highly sensitive thermoluminescent detector, Li 2 B 4 O 7 :Cu,Ag,P in the form of sintered pellets, developed at the Institute of Nuclear Sciences, Vin a . As a result of an advancement in the preparation procedure by the sensitising of basic copper activated lithium borate TL material, significant improvement in the TL sensitivity of Li 2 B 4 O 7 :Cu,Ag,P was gained. The glow curve of Li 2 B 4 O 7 :Cu,Ag,P consists of well defined main dosimetric peak situated at about 185-190 deg. C with the TL sensitivity which is about four to five times higher than that of LiF:Mg,Ti (TLD-100). From the experimental results a very wide linear dose response range, up to 10 3 Gy is evident. Dosimetric characteristics make sintered solid Li 2 B 4 O 7 :Cu,Ag,P TL detectors very promising for different dosimetry applications particularly in medical dosimetry and also for individual monitoring. (author)

  2. Nanoscale characterization and local piezoelectric properties of lead-free KNN-LT-LS thin films

    Science.gov (United States)

    Abazari, M.; Choi, T.; Cheong, S.-W.; Safari, A.

    2010-01-01

    We report the observation of domain structure and piezoelectric properties of pure and Mn-doped (K0.44,Na0.52,Li0.04)(Nb0.84,Ta0.1,Sb0.06)O3 (KNN-LT-LS) thin films on SrTiO3 substrates. It is revealed that, using piezoresponse force microscopy, ferroelectric domain structure in such 500 nm thin films comprised of primarily 180° domains. This was in accordance with the tetragonal structure of the films, confirmed by relative permittivity measurements and x-ray diffraction patterns. Effective piezoelectric coefficient (d33) of the films were calculated using piezoelectric displacement curves and shown to be ~53 pm V-1 for pure KNN-LT-LS thin films. This value is among the highest values reported for an epitaxial lead-free thin film and shows a great potential for KNN-LT-LS to serve as an alternative to PZT thin films in future applications.

  3. Nanoscale characterization and local piezoelectric properties of lead-free KNN-LT-LS thin films

    Energy Technology Data Exchange (ETDEWEB)

    Abazari, M; Safari, A [Glenn Howatt Electroceramics Laboratories, Department of Materials Science and Engineering, Rutgers-The state University of New Jersey, Piscataway, NJ 08854 (United States); Choi, T; Cheong, S-W [Rutgers Center for Emergent Materials, Department of Physics and Astronomy, Rutgers-The state University of New Jersey, Piscataway, NJ 08854 (United States)

    2010-01-20

    We report the observation of domain structure and piezoelectric properties of pure and Mn-doped (K{sub 0.44},Na{sub 0.52},Li{sub 0.04})(Nb{sub 0.84},Ta{sub 0.1},Sb{sub 0.06})O{sub 3} (KNN-LT-LS) thin films on SrTiO{sub 3} substrates. It is revealed that, using piezoresponse force microscopy, ferroelectric domain structure in such 500 nm thin films comprised of primarily 180{sup 0} domains. This was in accordance with the tetragonal structure of the films, confirmed by relative permittivity measurements and x-ray diffraction patterns. Effective piezoelectric coefficient (d{sub 33}) of the films were calculated using piezoelectric displacement curves and shown to be {approx}53 pm V{sup -1} for pure KNN-LT-LS thin films. This value is among the highest values reported for an epitaxial lead-free thin film and shows a great potential for KNN-LT-LS to serve as an alternative to PZT thin films in future applications.

  4. The neuregulin receptor ErbB-4 interacts with PDZ-containing proteins at neuronal synapses

    Science.gov (United States)

    Garcia, Rolando A. G.; Vasudevan, Kuzhalini; Buonanno, Andres

    2000-01-01

    Neuregulins regulate the expression of ligand- and voltage-gated channels in neurons and skeletal muscle by the activation of their cognate tyrosine kinase receptors, ErbB 1–4. The subcellular distribution and mechanisms that regulate the localization of ErbB receptors are unknown. We have found that ErbB receptors are present in brain subcellular fractions enriched for postsynaptic densities (PSD). The ErbB-4 receptor is unique among the ErbB proteins because its C-terminal tail (T-V-V) conforms to a sequence that binds to a protein motif known as the PDZ domain. Using the yeast two-hybrid system, we found that the C-terminal region of ErbB-4 interacts with the three related membrane-associated guanylate kinases (MAGUKs) PSD-95/SAP90, PSD-93/chapsyn-110, and SAP 102, which harbor three PDZ domains, as well as with β2-syntrophin, which has a single PDZ domain. As with N-methyl-d-aspartate (NMDA) receptors, ErbB4 interacts with the first two PDZ domains of PSD-95. Using coimmunoprecipitation assays, we confirmed the direct interactions between ErbB-4 and PSD-95 in transfected heterologous cells, as well as in vivo, where both proteins are coimmunoprecipitated from brain lysates. Moreover, evidence for colocalization of these proteins was also observed by immunofluorescence in cultured hippocampal neurons. ErbB-4 colocalizes with PSD-95 and NMDA receptors at a subset of excitatory synapses apposed to synaptophysin-positive presynaptic terminals. The capacity of ErbB receptors to interact with PDZ-domain proteins at cell junctions is conserved from invertebrates to mammals. As discussed, the interactions found between receptor tyrosine kinases and MAGUKs at neuronal synapses may have important implications for activity-dependent plasticity. PMID:10725395

  5. MaLT - Combined Motor and Language Therapy Tool for Brain Injury Patients Using Kinect.

    Science.gov (United States)

    Wairagkar, Maitreyee; McCrindle, Rachel; Robson, Holly; Meteyard, Lotte; Sperrin, Malcom; Smith, Andy; Pugh, Moyra

    2017-03-23

    The functional connectivity and structural proximity of elements of the language and motor systems result in frequent co-morbidity post brain injury. Although rehabilitation services are becoming increasingly multidisciplinary and "integrated", treatment for language and motor functions often occurs in isolation. Thus, behavioural therapies which promote neural reorganisation do not reflect the high intersystem connectivity of the neurologically intact brain. As such, there is a pressing need for rehabilitation tools which better reflect and target the impaired cognitive networks. The objective of this research is to develop a combined high dosage therapy tool for language and motor rehabilitation. The rehabilitation therapy tool developed, MaLT (Motor and Language Therapy), comprises a suite of computer games targeting both language and motor therapy that use the Kinect sensor as an interaction device. The games developed are intended for use in the home environment over prolonged periods of time. In order to track patients' engagement with the games and their rehabilitation progress, the game records patient performance data for the therapist to interrogate. MaLT incorporates Kinect-based games, a database of objects and language parameters, and a reporting tool for therapists. Games have been developed that target four major language therapy tasks involving single word comprehension, initial phoneme identification, rhyme identification and a naming task. These tasks have 8 levels each increasing in difficulty. A database of 750 objects is used to programmatically generate appropriate questions for the game, providing both targeted therapy and unique gameplay every time. The design of the games has been informed by therapists and by discussions with a Public Patient Involvement (PPI) group. Pilot MaLT trials have been conducted with three stroke survivors for the duration of 6 to 8 weeks. Patients' performance is monitored through MaLT's reporting facility

  6. A new practical method for the preparation of [3H6]-leukotrienes C4 and D4

    International Nuclear Information System (INIS)

    Belley, M.L.; Gareau, Y.; Zamboni, R.J.; Ahern, D.G.; Yang Hong

    1995-01-01

    A new method for the synthesis of highly deuterated or tritiated leukotrienes was developed. The higher reactivity of a terminal alkene compared to a 1,2-disubstituted one permitted the selective deuteration or tritiation of the diyne 14,15,19,19,20,20-hexadehydro LTC 4 troester 1. After hydrolysis, LTC 4 was obtained in 36% overall yield. An average of seven deuterium or tritium atoms was incorporated and the specific activity of the tritiated LTC 4 was greater than 180Ci/mmol. 1 was obtained from the addition of glutathione to 14,15,19,19,20,20-hexadehydro LTA 4 ethyl ester which was the product of a Wittig reaction between (3,8-nonanediyn-1-yl) triphenylphosphonium iodide and 5(S), 6(S), 7(E), 9(E) ethyl 5,6-epoxy-11-oxo-7,9-undecadienoate. (Author)

  7. Designing an efficient LT-code with unequal error protection for image transmission

    Science.gov (United States)

    S. Marques, F.; Schwartz, C.; Pinho, M. S.; Finamore, W. A.

    2015-10-01

    The use of images from earth observation satellites is spread over different applications, such as a car navigation systems and a disaster monitoring. In general, those images are captured by on board imaging devices and must be transmitted to the Earth using a communication system. Even though a high resolution image can produce a better Quality of Service, it leads to transmitters with high bit rate which require a large bandwidth and expend a large amount of energy. Therefore, it is very important to design efficient communication systems. From communication theory, it is well known that a source encoder is crucial in an efficient system. In a remote sensing satellite image transmission, this efficiency is achieved by using an image compressor, to reduce the amount of data which must be transmitted. The Consultative Committee for Space Data Systems (CCSDS), a multinational forum for the development of communications and data system standards for space flight, establishes a recommended standard for a data compression algorithm for images from space systems. Unfortunately, in the satellite communication channel, the transmitted signal is corrupted by the presence of noise, interference signals, etc. Therefore, the receiver of a digital communication system may fail to recover the transmitted bit. Actually, a channel code can be used to reduce the effect of this failure. In 2002, the Luby Transform code (LT-code) was introduced and it was shown that it was very efficient when the binary erasure channel model was used. Since the effect of the bit recovery failure depends on the position of the bit in the compressed image stream, in the last decade many e orts have been made to develop LT-code with unequal error protection. In 2012, Arslan et al. showed improvements when LT-codes with unequal error protection were used in images compressed by SPIHT algorithm. The techniques presented by Arslan et al. can be adapted to work with the algorithm for image compression

  8. X-ray and EPR study of reactions between B4C and TiO2

    International Nuclear Information System (INIS)

    Kakazey, M.; Vlasova, M.; Gonzalez-Rodriguez, J.G.; Dominguez-Patino, M.; Leder, R.

    2006-01-01

    X-ray diffraction and electron paramagnetic resonance (EPR) methods have been used to study the reaction process in a system of 95 wt.% of B 4 C + 5 wt.% TiO 2 . The addition of TiO 2 to B 4 C was effective in accelerating the removal of carbon inclusions. Two types of reactions between B 4 C and TiO 2 , starting at temperatures ∼1173 K, took place: (a) gas-transport exchange and (b) diffusion of Ti atoms into the B 4 C lattice. These reactions modify the number and type of donor centers in the B 4 C. The dependence of EPR line width on the number of donor centers in B 4 C (from conditions of sample treatment) is a useful method for investigating the formation of powders and ceramics based on B 4 C

  9. On the phototransferred thermoluminescence in MgB4O7:Dy

    International Nuclear Information System (INIS)

    Richmond, R.G.

    1987-01-01

    On exposure to ionizing radiations, the normal traps in MgB 4 0 7 :Dy can be emptied by the readout process only or by annealing at suitable temperatures, leaving the deep traps still intact. Subsequently, it is possible to repopulate the dosimetric peak by illuminating with u.v. light. Charge carriers released from the traps during the second readout give rise to a thermoluminescent output proportional to the ionizing radiation exposure and the u.v. radiant energy. This is called phototransferred thermoluminescence (PTTL). The PTTL method can be utilized for the reassessment of the initial γ-ray exposure. This paper presents the measurements of the intrinsic response of the commercially available MgB 4 0 7 :Dy to u.v. radiation, with a demonstration of its use for γ-ray dose re-estimation using the PTTL technique. (author)

  10. CODEX-B4C experiment. Core degradation test with boron carbide control rod

    International Nuclear Information System (INIS)

    Hozer, Z.; Nagy, I.; Windberg, P.; Balasko, M.; Matus, L.; Prokopiev, O.; Pinter, A.; Horvath, M.; Gyenes, Gy.; Czitrovszky, A.; Nagy, A.; Jani, P.

    2003-11-01

    The CODEX-B4C bundle test has been successfully performed on 25 th May 2001 in the framework of the COLOSS project of the EU 5 th FWP. The high temperature degradation of a VVER-1000 type bundle with B 4 C control rod was investigated with electrically heated fuel rods. The experiment was carried out according to a scenario selected in favour of methane formation. Degradation of control rod and fuel bundle took place at temperatures ∼2000 deg C, cooling down of the bundle was performed in steam atmosphere. The gas composition measurement indicated no methane production during the experiment. High release of aerosols was detected in the high temperature oxidation phase. The on-line measured data are collected into a database and are available for code validation and development. (author)

  11. Microstructural analysis of aluminum oxide boron carbide (Al2 O3-B4 C)

    International Nuclear Information System (INIS)

    Oliveira, E.E.M.; Bressiani, Ana H.A.; Bressiani, J.C.

    1996-01-01

    The densification Al 2 O 3 -B 4 C of composite was accomplished under two conditions: I- tungsten resistance furnace in commercial argon atmosphere without gas treatment system.II- graphite resistance furnace in argon atmosphere with gas treatment for humidity removal. The sintering with gas treatment showed higher density and smaller loss of mass for all composition related to the sintering in tungsten resistance furnace without gas treatment system. Microstructural characterization also showed that grain growth of alumina matrix is greatly influenced by particle size and concentration of B 4 C. Samples sintered at temperatures higher than 1750 deg C without gas treatment presented the formation of phase Al 3 B O 6 which was identified by transmission electron microscopy. (author)

  12. Modeling of wear behavior of Al/B_4C composites produced by powder metallurgy

    International Nuclear Information System (INIS)

    Sahin, Ismail; Bektas, Asli; Guel, Ferhat; Cinci, Hanifi

    2017-01-01

    Wear characteristics of composites, Al matrix reinforced with B_4C particles percentages of 5, 10,15 and 20 produced by the powder metallurgy method were studied in this study. For this purpose, a mixture of Al and B_4C powders were pressed under 650 MPa pressure and then sintered at 635 C. The analysis of hardness, density and microstructure was performed. The produced samples were worn using a pin-on-disk abrasion device under 10, 20 and 30 N load through 500, 800 and 1200 mesh SiC abrasive papers. The obtained wear values were implemented in an artificial neural network (ANN) model having three inputs and one output using feed forward backpropagation Levenberg-Marquardt algorithm. Thus, the optimum wear conditions and hardness values were determined.

  13. Expanding the clinical and mutational spectrum of B4GALT7-spondylodysplastic Ehlers-Danlos syndrome.

    Science.gov (United States)

    Ritelli, Marco; Dordoni, Chiara; Cinquina, Valeria; Venturini, Marina; Calzavara-Pinton, Piergiacomo; Colombi, Marina

    2017-09-07

    Spondylodysplastic EDS (spEDS) is a rare connective tissue disorder that groups the phenotypes caused by biallelic B4GALT7, B3GALT6, and SLC39A13 mutations. In the 2017 EDS nosology, minimal criteria (general and gene-specific) for a clinical suspicion of spEDS have been proposed, but molecular analysis is required to reach a definite diagnosis. The majority of spEDS patients presented with short stature, skin hyperextensibility, facial dysmorphisms, peculiar radiological findings, muscle hypotonia and joint laxity and/or its complications. To date only 7 patients with β4GALT7-deficiency (spEDS-B4GALT7) have been described and their clinical data suggested that, in addition to short stature and muscle hypotonia, radioulnar synostosis, hypermetropia, and delayed cognitive development might be a hallmark of this specific type of spEDS. Additional 22 patients affected with an overlapping phenotype, i.e., Larsen of Reunion Island syndrome, all carrying a homozygous B4GALT7 mutation, are also recognized. Herein, we report on a 30-year-old Moroccan woman who fitted the minimal criteria to suspect spEDS, but lacked radioulnar synostosis and intellectual disability and presented with neurosensorial hearing loss and limb edema of lymphatic origin. Sanger sequencing of B4GALT7 was performed since the evaluation of the spEDS gene-specific minor criteria suggested this specific subtype. Mutational screening revealed the homozygous c.829G>T, p.Glu277* pathogenetic variant leading to aberrant splicing. Our findings expand both the clinical and mutational spectrum of this ultrarare connective tissue disorder. The comparison of the patient's features with those of the other spEDS and Larsen of Reunion Island syndrome patients reported up to now offers future perspectives for spEDS nosology and clinical research in this field.

  14. ∆DNMT3B4-del Contributes to Aberrant DNA Methylation Patterns in Lung Tumorigenesis

    Directory of Open Access Journals (Sweden)

    Mark Z. Ma

    2015-10-01

    Full Text Available Aberrant DNA methylation is a hallmark of cancer but mechanisms contributing to the abnormality remain elusive. We have previously shown that ∆DNMT3B is the predominantly expressed form of DNMT3B. In this study, we found that most of the lung cancer cell lines tested predominantly expressed DNMT3B isoforms without exons 21, 22 or both 21 and 22 (a region corresponding to the enzymatic domain of DNMT3B termed DNMT3B/∆DNMT3B-del. In normal bronchial epithelial cells, DNMT3B/ΔDNMT3B and DNMT3B/∆DNMT3B-del displayed equal levels of expression. In contrast, in patients with non-small cell lung cancer NSCLC, 111 (93% of the 119 tumors predominantly expressed DNMT3B/ΔDNMT3B-del, including 47 (39% tumors with no detectable DNMT3B/∆DNMT3B. Using a transgenic mouse model, we further demonstrated the biological impact of ∆DNMT3B4-del, the ∆DNMT3B-del isoform most abundantly expressed in NSCLC, in global DNA methylation patterns and lung tumorigenesis. Expression of ∆DNMT3B4-del in the mouse lungs resulted in an increased global DNA hypomethylation, focal DNA hypermethylation, epithelial hyperplastia and tumor formation when challenged with a tobacco carcinogen. Our results demonstrate ∆DNMT3B4-del as a critical factor in developing aberrant DNA methylation patterns during lung tumorigenesis and suggest that ∆DNMT3B4-del may be a target for lung cancer prevention.

  15. Growth and luminescent properties of Li2B4O7 single crystal doped with Cu

    International Nuclear Information System (INIS)

    Bui The Huy; Bui Minh Ly; Vu Xuan Quang; Huynh Ky Hanh; Doan Phan Thao Tien; Vinh Hao; Tran Ngoc

    2009-01-01

    The authors have primarily succeeded in the study of the technology for growing single crystal Li 2 B 4 O 7 doped with Cu ions by Bridgman technique. The TL-3D spectra show peaks at around 375 nm (3d 9 4s → 3d 10 radiative excitation transition). This success opened up an opportunity in the radiotherapy to manufacture scintillators for neutron detection. The kinetic parameters of thermal stimulation luminescence were investigated by the three point method.

  16. Structural modifications induced by ion irradiation and temperature in boron carbide B4C

    Science.gov (United States)

    Victor, G.; Pipon, Y.; Bérerd, N.; Toulhoat, N.; Moncoffre, N.; Djourelov, N.; Miro, S.; Baillet, J.; Pradeilles, N.; Rapaud, O.; Maître, A.; Gosset, D.

    2015-12-01

    Already used as neutron absorber in the current French nuclear reactors, boron carbide (B4C) is also considered in the future Sodium Fast Reactors of the next generation (Gen IV). Due to severe irradiation conditions occurring in these reactors, it is of primary importance that this material presents a high structural resistance under irradiation, both in the ballistic and electronic damage regimes. Previous works have shown an important structural resistance of boron carbide even at high neutron fluences. Nevertheless, the structural modification mechanisms due to irradiation are not well understood. Therefore the aim of this paper is to study structural modifications induced in B4C samples in different damage regimes. The boron carbide pellets were shaped and sintered by using spark plasma sintering method. They were then irradiated in several conditions at room temperature or 800 °C, either by favoring the creation of ballistic damage (between 1 and 3 dpa), or by favoring the electronic excitations using 100 MeV swift iodine ions (Se ≈ 15 keV/nm). Ex situ micro-Raman spectroscopy and Doppler broadening of annihilation radiation technique with variable energy slow positrons were coupled to follow the evolution of the B4C structure under irradiation.

  17. Synthesis, crystal structure, and nonlinear optical properties of Bi2Cu5B4O14

    International Nuclear Information System (INIS)

    Pan Shilie; Smit, Jared P.; Marvel, Michael R.; Stampler, Evan S.; Haag, Jacob M.; Baek, Jaewook; Halasyamani, P. Shiv; Poeppelmeier, Kenneth R.

    2008-01-01

    Bi 2 Cu 5 B 4 O 14 crystallizes in the noncentrosymmetric triclinic space group P1 (No. 1) with cell parameters a=10.1381(11) A, b=9.3917(11) A, c=3.4566(4) A, α=105.570(2) o , β=92.275(2) o , γ=107.783(2) o , Z=1 and R 1 =0.0401 and wR 2 =0.0980. It is a layered structure that is built up from sheets of rectangular CuO 4 and trigonal BO 3 groups. The sheets are connected by infinite chains of edge shared BiO 6 polyhedra that intersect the bc plane at an angle slightly greater than 90 o . The second-harmonic generation efficiency of Bi 2 Cu 5 B 4 O 14 , using 1064 nm radiation, is about one half times that of KH 2 PO 4 . - Graphical abstract: The figure shows a layered structure that is built up from sheets of distorted rectangular CuO 4 and trigonal BO 3 groups. The sheets are connected by infinite chains of edge shared BiO 6 polyhedra that intersect the bc plane. These distortions lead to the second-harmonic generation efficiency of Bi 2 Cu 5 B 4 O 14 about one half times that of KH 2 PO 4 Display Omitted

  18. Production of Fumonisin B-2 and B-4 by Aspergillus niger on Grapes and Raisins

    DEFF Research Database (Denmark)

    Mogensen, Jesper Mølgaard; Frisvad, Jens Christian; Thrane, Ulf

    2010-01-01

    The recent discovery of fumonisin production in Aspergillus niger, raises concerns about the presence of these mycotoxins in grapes and raisins as well as other commodities where A. niger is a frequent contaminant. Here we investigate the potential production of fumonisins in A. niger cultured...... on grapes and raisins. Sixty-six A. niger, 4 A. tubingensis, and 16 A. acidus strains isolated from raisins were tested for fumonisin production on laboratory media. Neither A. tubingensis nor A. acidus strains produced fumonisins, but 77% of A. niger strains did. None of the strains produced ochratoxin A....... Ten selected fumonisin producing A. niger strains were further able to produce fumonisin B2 and fumonisin B4 on grapes in the range 171−7841 μg fumonisin B2/kg and 14−1157 μg fumonisin B4/kg. Four selected strains were able to produce fumonisin B2 (5−6476 μg/kg) and fumonisin B4 (12−672 μg...

  19. Thermoluminescence characteristics of Li2B4O7 single crystal dosimeters doped with Mn

    International Nuclear Information System (INIS)

    Ekdal, E.; Karalı, T.; Kelemen, A.; Ignatovych, M.; Holovey, V.; Harmansah, C.

    2014-01-01

    In this study, thermoluminescence (TL) characterization of newly developed Li 2 B 4 O 7 :Mn single crystal phosphor is reported. It is a very attractive material in personal dosimetry because of its near tissue equivalency (Z eff =7.25). The crystal was grown by the Czochralski method from high purity compounds. Glow curve, dose response, and fading and reproducibility properties of this material were investigated. Its TL glow curve showed two well separated peaks at about 105 and 220 °C with a heating rate of 2 °C s −1 . The main peak at 220 °C has a linear dose response of up to 60 Gy. The thermal fading ratio of the material is about 8% for the main peak in 10 days. The results showed that there is no significant variation of TL responses for 15 sequential measurements. Apart from the dosimetric properties above, the TL kinetic parameters of the main peak at 220 °C of Li 2 B 4 O 7 :Mn single crystal phosphor were also calculated using the various heating rates method. Activation energy and frequency factor were found as 1.21 eV and 3.75×10 11 s −1 , respectively. - Highlights: • Li 2 B 4 O 7 :Mn single crystal was investigated in terms of TL characteristics. • The material shows highly satisfactory dosimetric properties. • Various heating rates method was used for determining the kinetic parameter

  20. CysLT2 receptor activation is involved in LTC4-induced lung air-trapping in guinea pigs.

    Science.gov (United States)

    Sekioka, Tomohiko; Kadode, Michiaki; Yonetomi, Yasuo; Kamiya, Akihiro; Fujita, Manabu; Nabe, Takeshi; Kawabata, Kazuhito

    2017-01-05

    CysLT 1 receptors are known to be involved in the pathogenesis of asthma. However, the functional roles of CysLT 2 receptors in this condition have not been determined. The purpose of this study is to develop an experimental model of CysLT 2 receptor-mediated LTC 4 -induced lung air-trapping in guinea pigs and use this model to clarify the mechanism underlying response to such trapping. Because LTC 4 is rapidly converted to LTD 4 by γ-glutamyltranspeptidase (γ-GTP) under physiological conditions, S-hexyl GSH was used as a γ-GTP inhibitor. In anesthetized artificially ventilated guinea pigs with no S-hexyl GSH treatment, i.v. LTC 4 -induced bronchoconstriction was almost completely inhibited by montelukast, a CysLT 1 receptor antagonist, but not by BayCysLT 2 RA, a CysLT 2 receptor antagonist. The inhibitory effect of montelukast was diminished by treatment with S-hexyl GSH, whereas the effect of BayCysLT 2 RA was enhanced with increasing dose of S-hexyl GSH. Macroscopic and histological examination of lung tissue isolated from LTC 4 -/S-hexyl-GSH-treated guinea pigs revealed air-trapping expansion, particularly at the alveolar site. Inhaled LTC 4 in conscious guinea pigs treated with S-hexyl GSH increased both airway resistance and airway hyperinflation. On the other hand, LTC 4 -induced air-trapping was only partially suppressed by treatment with the bronchodilator salmeterol. Although montelukast inhibition of LTC 4 -induced air-trapping was weak, treatment with BayCysLT 2 RA resulted in complete suppression of this air-trapping. Furthermore, BayCysLT 2 RA completely suppressed LTC 4 -induced airway vascular hyperpermeability. In conclusion, we found in this study that CysLT 2 receptors mediate LTC 4 -induced bronchoconstriction and air-trapping in S-hexyl GSH-treated guinea pigs. It is therefore believed that CysLT 2 receptors contribute to asthmatic response involving air-trapping. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Expression of the Blood-Group-Related Gene B4galnt2 Alters Susceptibility to Salmonella Infection.

    Directory of Open Access Journals (Sweden)

    Philipp Rausch

    2015-07-01

    Full Text Available Glycans play important roles in host-microbe interactions. Tissue-specific expression patterns of the blood group glycosyltransferase β-1,4-N-acetylgalactosaminyltransferase 2 (B4galnt2 are variable in wild mouse populations, and loss of B4galnt2 expression is associated with altered intestinal microbiota. We hypothesized that variation in B4galnt2 expression alters susceptibility to intestinal pathogens. To test this, we challenged mice genetically engineered to express different B4galnt2 tissue-specific patterns with a Salmonella Typhimurium infection model. We found B4galnt2 intestinal expression was strongly associated with bacterial community composition and increased Salmonella susceptibility as evidenced by increased intestinal inflammatory cytokines and infiltrating immune cells. Fecal transfer experiments demonstrated a crucial role of the B4galnt2-dependent microbiota in conferring susceptibility to intestinal inflammation, while epithelial B4galnt2 expression facilitated epithelial invasion of S. Typhimurium. These data support a critical role for B4galnt2 in gastrointestinal infections. We speculate that B4galnt2-specific differences in host susceptibility to intestinal pathogens underlie the strong signatures of balancing selection observed at the B4galnt2 locus in wild mouse populations.

  2. Endothelial ErbB4 deficit induces alterations in exploratory behavior and brain energy metabolism in mice.

    Science.gov (United States)

    Wu, Gang; Liu, Xiu-Xiu; Lu, Nan-Nan; Liu, Qi-Bing; Tian, Yun; Ye, Wei-Feng; Jiang, Guo-Jun; Tao, Rong-Rong; Han, Feng; Lu, Ying-Mei

    2017-06-01

    The receptor tyrosine kinase ErbB4 is present throughout the primate brain and has a distinct functional profile. In this study, we investigate the potential role of endothelial ErbB4 receptor signaling in the brain. Here, we show that the endothelial cell-specific deletion of ErbB4 induces decreased exploratory behavior in adult mice. However, the water maze task for spatial memory and the memory reconsolidation test reveal no changes; additionally, we observe no impairment in CaMKII phosphorylation in Cdh5Cre;ErbB4 f/f mice, which indicates that the endothelial ErbB4 deficit leads to decreased exploratory activity rather than direct memory deficits. Furthermore, decreased brain metabolism, which was measured using micro-positron emission tomography, is observed in the Cdh5Cre;ErbB4 f/f mice. Consistently, the immunoblot data demonstrate the downregulation of brain Glut1, phospho-ULK1 (Ser555), and TIGAR in the endothelial ErbB4 conditional knockout mice. Collectively, our findings suggest that endothelial ErbB4 plays a critical role in regulating brain function, at least in part, through maintaining normal brain energy homeostasis. Targeting ErbB4 or the modulation of endothelial ErbB4 signaling may represent a rational pharmacological approach to treat neurological disorders. © 2017 John Wiley & Sons Ltd.

  3. Preliminary calculation with code CONTEMPT-LT for spray cooling tests with JAERI model containment vessel

    International Nuclear Information System (INIS)

    Tanaka, Mitsugu

    1978-01-01

    LWR plants have a containment spray system to reduce the escape of radioactive material to the environment in a loss-of-coolant accident (LOCA) by washing out fission products, especially radioiodine, and condensing the steam to lower the pressure. For carrying out the containment spray tests, pressure and temperature behaviour of the JAERI Model Containment Vessel in spray cooling has been calculated with computer program CONTEMPT-LT. The following could be studied quantitatively: (1) pressure and temperature raise rates for steam addition rate and (2) pressure fall rate for spray flow rate and spray heat transfer efficiency. (auth.)

  4. SWAAM-LT: The long-term, sodium/water reaction analysis method computer code

    International Nuclear Information System (INIS)

    Shin, Y.W.; Chung, H.H.; Wiedermann, A.H.; Tanabe, H.

    1993-01-01

    The SWAAM-LT Code, developed for analysis of long-term effects of sodium/water reactions, is discussed. The theoretical formulation of the code is described, including the introduction of system matrices for ease of computer programming as a general system code. Also, some typical results of the code predictions for available large scale tests are presented. Test data for the steam generator design with the cover-gas feature and without the cover-gas feature are available and analyzed. The capabilities and limitations of the code are then discussed in light of the comparison between the code prediction and the test data

  5. Identification of a umuDC locus in Salmonella typhimurium LT2

    International Nuclear Information System (INIS)

    Smith, C.M.; Eisenstadt, E.

    1989-01-01

    The umuDC operon of Escherichia coli is required for efficient mutagenesis by UV light and many other DNA-damaging agents. The existence of a umuDC analog in Salmonella typhimurium has been questioned. With DNA probes to the E. coli umuD and umuC genes, we detected, by Southern blot hybridization, sequences similar to both of these genes in S. typhimurium LT2. We also confirmed that the presence of cloned E. coli umuD enhances the UV mutability and resistance of S. typhimurium. Our data strongly suggest that S. typhimurium contains a functional umuDC operon

  6. LT^2C^2: A language of thought with Turing-computable Kolmogorov complexity

    Directory of Open Access Journals (Sweden)

    Santiago Figueira

    2013-03-01

    Full Text Available In this paper, we present a theoretical effort to connect the theory of program size to psychology by implementing a concrete language of thought with Turing-computable Kolmogorov complexity (LT^2C^2 satisfying the following requirements: 1 to be simple enough so that the complexity of any given finite binary sequence can be computed, 2 to be based on tangible operations of human reasoning (printing, repeating,. . . , 3 to be sufficiently powerful to generate all possible sequences but not too powerful as to identify regularities which would be invisible to humans. We first formalize LT^2C^2, giving its syntax and semantics, and defining an adequate notion of program size. Our setting leads to a Kolmogorov complexity function relative to LT^2C^2 which is computable in polynomial time, and it also induces a prediction algorithm in the spirit of Solomonoff’s inductive inference theory. We then prove the efficacy of this language by investigating regularities in strings produced by participants attempting to generate random strings. Participants had a profound understanding of randomness and hence avoided typical misconceptions such as exaggerating the number of alternations. We reasoned that remaining regularities would express the algorithmic nature of human thoughts, revealed in the form of specific patterns. Kolmogorov complexity relative to LT^2C^2 passed three expected tests examined here: 1 human sequences were less complex than control PRNG sequences, 2 human sequences were not stationary showing decreasing values of complexity resulting from fatigue 3 each individual showed traces of algorithmic stability since fitting of partial data was more effective to predict subsequent data than average fits. This work extends on previous efforts to combine notions of Kolmogorov complexity theory and algorithmic information theory to psychology, by explicitly proposing a language which may describe the patterns of human thoughts.Received: 12

  7. On the Solution of the Rational Matrix Equation X=Q+LX−1LT

    Directory of Open Access Journals (Sweden)

    Heike Faßbender

    2007-01-01

    Full Text Available We study numerical methods for finding the maximal symmetric positive definite solution of the nonlinear matrix equation X=Q+LX−1LT, where Q is symmetric positive definite and L is nonsingular. Such equations arise for instance in the analysis of stationary Gaussian reciprocal processes over a finite interval. Its unique largest positive definite solution coincides with the unique positive definite solution of a related discrete-time algebraic Riccati equation (DARE. We discuss how to use the butterfly SZ algorithm to solve the DARE. This approach is compared to several fixed-point and doubling-type iterative methods suggested in the literature.

  8. Type II heat-labile enterotoxins from 50 diverse Escherichia coli isolates belong almost exclusively to the LT-IIc family and may be prophage encoded.

    Directory of Open Access Journals (Sweden)

    Michael G Jobling

    Full Text Available Some enterotoxigenic Escherichia coli (ETEC produce a type II heat-labile enterotoxin (LT-II that activates adenylate cyclase in susceptible cells but is not neutralized by antisera against cholera toxin or type I heat-labile enterotoxin (LT-I. LT-I variants encoded by plasmids in ETEC from humans and pigs have amino acid sequences that are ≥ 95% identical. In contrast, LT-II toxins are chromosomally encoded and are much more diverse. Early studies characterized LT-IIa and LT-IIb variants, but a novel LT-IIc was reported recently. Here we characterized the LT-II encoding loci from 48 additional ETEC isolates. Two encoded LT-IIa, none encoded LT-IIb, and 46 encoded highly related variants of LT-IIc. Phylogenetic analysis indicated that the predicted LT-IIc toxins encoded by these loci could be assigned to 6 subgroups. The loci corresponding to individual toxins within each subgroup had DNA sequences that were more than 99% identical. The LT-IIc subgroups appear to have arisen by multiple recombinational events between progenitor loci encoding LT-IIc1- and LT-IIc3-like variants. All loci from representative isolates encoding the LT-IIa, LT-IIb, and each subgroup of LT-IIc enterotoxins are preceded by highly-related genes that are between 80 and 93% identical to predicted phage lysozyme genes. DNA sequences immediately following the B genes differ considerably between toxin subgroups, but all are most closely related to genomic sequences found in predicted prophages. Together these data suggest that the LT-II loci are inserted into lambdoid type prophages that may or may not be infectious. These findings raise the possibility that production of LT-II enterotoxins by ETEC may be determined by phage conversion and may be activated by induction of prophage, in a manner similar to control of production of Shiga-like toxins by converting phages in isolates of enterohemmorhagic E. coli.

  9. LT-CFB. Applications and follow-up. CP Kelco. Appendix 1. [Low Temperature Circulating Fluid Bed gasifier]; LT-CFB. Anvendelsesmuligheder og opfoelgning. CP Kelco. Bilag 1

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-04-15

    This appendix describes how LT-CFB advantageously can gasify residual products at the company CP Kelco's factory. CP Kelco produces the gelation, thickeners and stabilizers carrageenan and pectin from seaweed and citrus peel. Residues from the production consist of a fiber-containing biological material, which has a calorific value of dry matter about 15 to 20 MJ / kg. In addition, there are waste products from the wastewater treatment plant, which are also proposed re-used in the project. The report describes the economic analyses, the overall data and system design for two scenarios, whereas the description of the plant capacities, sizes and detailed data etc. are described only for one scenario. In addition to savings in the purchase of natural gas the gas production also results in a significant reduction in CO{sub 2} emissions, the product gas being characterized as CO{sub 2} neutral. Since CP Kelco is subject to the CO{sub 2} quota system the saved amount of CO{sub 2} emissions represents a significant value. In the economic analyses, the value of 1 ton of CO{sub 2} is set at DKK 100. (LN)

  10. Sputtering characteristics of B4C-overlaid graphite for keV energy deuterium ion irradiation

    International Nuclear Information System (INIS)

    Gotoh, Y.; Yamaki, T.; Ando, T.; Jimbou, R.; Ogiwara, N.; Saidoh, M.; Teruyama, K.

    1992-01-01

    Two types of B 4 C-overlaid graphite (CFC), conversion and CVD B 4 C, together with bare CFC (PCC-2S) and/or HP B 4 C, were investigated with respect to erosion yields for 1 keV D + , D 2 /CD 4 TDS after 1 keV D + implantation, and thermal diffusivity/conductivity, in a temperature range from 300 to 1400 K. The erosion yields of both conversion and CVD B 4 C were found to be much lower than that of the bare CFC (PCC-2S), in both chemical sputtering (600-1100 K) and RES (1200-1400 K) temperature regions. The D 2 TDS peak of the conversion B 4 C was found to be located at nearly 200 K lower temperature than that of the bare CFC (PCC-2S), indicating much lower activation energy for detrapping/recombination of trapped D in the conversion B 4 C and in the CFC. The CD 4 TDS peak of the conversion B 4 C was found to be much weaker in intensity than that of the bare CFC (PCC-2S), in agreement with the present erosion yield results. Thermal diffusivities and conductivities of both the conversion B 4 C/PCC-2S and the CVD B 4 C, were measured to be nearly 1/10 of that of the bare CFC (PCC-2S), and to decrease with increasing temperatures. (orig.)

  11. Evolving role of 2B4/CD244 in T and NK cell responses during virus infection

    Directory of Open Access Journals (Sweden)

    Stephen Noel Waggoner

    2012-12-01

    Full Text Available The signaling lymphocyte activation molecule (SLAM family receptor, 2B4/CD244, was first implicated in anti-viral immunity by the discovery that mutations of the SLAM-associated protein, SAP/SH2D1A, impaired 2B4-dependent stimulation of T and natural killer (NK cell anti-viral functions in X-linked lymphoproliferative (XLP syndrome patients with uncontrolled Epstein-Barr virus (EBV infections. Engagement of 2B4 has been variably shown to either activate or inhibit lymphocytes which express this receptor. While SAP expression is required for stimulatory functions of 2B4 on lymphocytes, it remains unclear whether inhibitory signals derived from 2B4 can predominate even in the presence of SAP. Regardless, mounting evidence suggests that 2B4 expression by NK and CD8 T cells is altered by virus infection in mice as well as in humans, and 2B4-mediated signaling may be an important determinant of effective immune control of chronic virus infections. In this review, recent findings regarding the expression and function of 2B4 as well as SAP on T and NK cells during virus infection is discussed, with a focus on the role of 2B4-CD48 interactions in crosstalk between innate and adaptive immunity.

  12. The effects of LT-SN on energy dissipation and lifetime in wireless sensor networks

    Directory of Open Access Journals (Sweden)

    Zeydin Pala

    2016-11-01

    Full Text Available Wireless sensor networks (WSNs still attract the attention of researchers, users and the private sector despite their low power and low range tendency for malfunction. This attraction towards WSNs results from their low cost structure and the solutions they offer for many prevalent problems. Many conditions, which remain unforeseen or unexpected during the design of the system, may arise after the initialization of the system. Similarly, many situations where security vulnerabilities take place may emerge in time in WSNs operating normally. In this study, we called nodes which enter sleeping mode without any further waking up and causing a sparser number of nodes in the network without any function in data transmission as Long-Term Sleep Nodes (LT-SN; and considered energy spaces caused by such nodes as a problem; and established two Linear Programming (LP models based on the efficiency of the present nodes. We offered two different models which present the effect of sensor nodes, which were initially operating in wireless sensor network environment and did not wake up following sleep mode, on network lifetime. The results of the present study report that as the number of LT-SN increases, the lifetime of the network decreases.

  13. Effects of phthalates on the human corneal endothelial cell line B4G12

    DEFF Research Database (Denmark)

    Krüger, Tanja; Cao, Yi; Kjærgaard, Søren K.

    2012-01-01

    Phthalates are industrial chemicals used in many cosmetics. We evaluated an in vitro model for eye irritancy testing using the human corneal endothelial cell line B4G12. Cell proliferation and toxicity were assessed after exposing to di-n-butyl phthalate (DBP), benzyl butyl phthalate (BBP), di-2...... toxicity was observed for DBP and BBP. Upon DBP exposure at nontoxic concentrations, a significant increased gene expression and cytokine cell secretion were observed for interleukin-1ß (IL-1ß) and IL-8, and also an increased IL-6 secretion was observed. In conclusion, the human corneal endothelial cell...

  14. Simulation-Based e-Learning Tools for Science,Engineering, and Technology Education(SimBeLT)

    Science.gov (United States)

    Davis, Doyle V.; Cherner, Y.

    2006-12-01

    The focus of Project SimBeLT is the research, development, testing, and dissemination of a new type of simulation-based integrated e-learning set of modules for two-year college technical and engineering curricula in the areas of thermodynamics, fluid physics, and fiber optics that can also be used in secondary schools and four-year colleges. A collection of sophisticated virtual labs is the core component of the SimBeLT modules. These labs will be designed to enhance the understanding of technical concepts and underlying fundamental principles of these topics, as well as to master certain performance based skills online. SimBeLT software will help educators to meet the National Science Education Standard that "learning science and technology is something that students do, not something that is done to them". A major component of Project SimBeLT is the development of multi-layered technology-oriented virtual labs that realistically mimic workplace-like environments. Dynamic data exchange between simulations will be implemented and links with instant instructional messages and data handling tools will be realized. A second important goal of Project SimBeLT labs is to bridge technical skills and scientific knowledge by enhancing the teaching and learning of specific scientific or engineering subjects. SimBeLT builds upon research and outcomes of interactive teaching strategies and tools developed through prior NSF funding (http://webphysics.nhctc.edu/compact/index.html) (Project SimBeLT is partially supported by a grant from the National Science Foundation DUE-0603277)

  15. ErbB4 localization to cardiac myocyte nuclei, and its role in myocyte DNA damage response

    International Nuclear Information System (INIS)

    Icli, Basak; Bharti, Ajit; Pentassuglia, Laura; Peng, Xuyang; Sawyer, Douglas B.

    2012-01-01

    Highlights: ► ErbB4 localizes to cardiac myocyte nuclei as a full-length receptor. ► Cardiac myocytes express predominantly JM-a/CYT-1 ErbB4. ► Myocyte p53 activation in response to doxorubicin requires ErbB4 activity. -- Abstract: The intracellular domain of ErbB4 receptor tyrosine kinase is known to translocate to the nucleus of cells where it can regulate p53 transcriptional activity. The purpose of this study was to examine whether ErbB4 can localize to the nucleus of adult rat ventricular myocytes (ARVM), and regulate p53 in these cells. We demonstrate that ErbB4 does locate to the nucleus of cardiac myocytes as a full-length protein, although nuclear location occurs as a full-length protein that does not require Protein Kinase C or γ-secretase activity. Consistent with this we found that only the non-cleavable JM-b isoform of ErbB4 is expressed in ARVM. Doxorubicin was used to examine ErbB4 role in regulation of a DNA damage response in ARVM. Doxorubicin induced p53 and p21 was suppressed by treatment with AG1478, an EGFR and ErbB4 kinase inhibitor, or suppression of ErbB4 expression with small interfering RNA. Thus ErbB4 localizes to the nucleus as a full-length protein, and plays a role in the DNA damage response induced by doxorubicin in cardiac myocytes.

  16. Battery for ECT Related Cognitive Deficits (B4ECT-ReCoDe): development and validation.

    Science.gov (United States)

    Viswanath, Biju; Harihara, Shashidhara N; Nahar, Abhinav; Phutane, Vivek Haridas; Taksal, Aarati; Thirthalli, Jagadisha; Gangadhar, Bangalore N

    2013-06-01

    The use of electroconvulsive therapy (ECT) in treatment of psychiatric disorders is associated with adverse cognitive effects. There is a need to develop a short assessment tool of cognitive functions during the course of ECT. This study aimed at developing and validating a short, sensitive battery to assess cognitive deficits associated with ECT in India. Battery for ECT Related Cognitive Deficits (B4ECT-ReCoDe), a brief cognitive battery (20-30 min) to assess verbal, visual, working and autobiographic memory, sustained attention, psychomotor speed and subjective memory impairment, was administered to 30 in-patients receiving bilateral ECT, one day after the 1st, 3rd and 6th ECT. Data was analysed using repeated measures analysis of variance and Pearson's correlation. Significant deficits were found in verbal, visual and autobiographic memory, psychomotor speed. Subjective experience of memory loss correlated positively with verbal memory impairment. B4ECT-ReCoDe, a brief, sensitive measure of cognitive impairments associated with ECT can be used in routine clinical practice. Copyright © 2013 Elsevier B.V. All rights reserved.

  17. Modelling of the interactions between B4C and stainless steel at high temperatures

    International Nuclear Information System (INIS)

    Veshchunov, M.S.

    1995-01-01

    Results of detailed chemical-analytical examinations of B 4 C/stainless steel (s.s.) reaction couples obtained at temperatures of 1000, 1100 and 1200 C, and a theoretical model developed on the basis of these results, which describes the reaction layers growth kinetics, are presented. The examinations were carried out by AES and XMA methods to measure concentration profiles of different elements in the various phases and the thicknesses of the formed reaction layers as function of time to determine the growth kinetics. A new approach for modelling of diffusion mass transfer through a two-phase zone in multicomponent systems is further developed for the description of the growth kinetics of the reaction layer consisting of Me 2 B (Me≡Fe, Cr, Ni) precipitates in the stainless steel matrix. Diffusion coefficients of Cr in all phases of the reaction zone are calculated. These data together with the measured boundary concentrations of the elements allow the complete description of the B 4 C/s.s. interaction kinetics at the examined test temperatures by the proposed model. (orig.)

  18. Characterization of B4C-composite-reinforced aluminum alloy composites

    Science.gov (United States)

    Singh, Ram; Rai, R. N.

    2018-04-01

    Dry sliding wear tests conducted on Pin-on-disk wear test machine. The rotational speed of disc is ranging from (400-600rpm) and under loads ranging from (30-70 N) the contact time between the disc and pin is constant for each pin specimen of composites is 15 minute. In all manufacturing industries the uses of composite materials has been increasing globally, In the present study, an aluminum 5083 alloy is used as the matrix and 5% of weight percentage of Boron Carbide (B4C) as the reinforcing material. The composite is produced using stir casting technique. This is cost effective method. The aluminum 5083 matrix can be strengthened by reinforcing with hard ceramic particles like silicon carbide and boron carbide. In this experiment, aluminum 5083 alloy is selected as one of main material for making parts of the ship it has good mechanical properties, good corrosion resistance and it is can welded very easily and does have good strength. The samples are tested for hardness and tensile strength. The mechanical properties like Hardness can be increased by reinforcing aluminum 5083alloy 5% boron carbide (B4C) particles and tensile strength. Finally the Scanning Electron Microscope (SEM) analysis and EDS is done, which helps to study topography of composites and it produces images of a sample by scanning it with a focused beam of electrons and the presence of composition found in the matrix.

  19. Production and characterization of compounds based on MgB4O7 for application in dosimetry

    International Nuclear Information System (INIS)

    Souza, Luiza Freire de

    2016-01-01

    Many materials with luminescent properties are used for ionizing radiation dosimetry through the thermoluminescence (TL) and optically stimulated luminescence (OSL) techniques. Detectors based on lithium fluoride (LiF), calcium sulphate (CaSO 4 ) and aluminum oxide (Al 2 O 3 ), doped or codoped with various elements, are the TL or OSL commercial dosimeters most widely used currently. However, several researches are focused to the development of new TL /OSL materials in intention to enhance the dosimetric properties, in view that no TL/OSL dosimeter has all the ideal characteristics for monitoring the radiation. In this context, magnesium tetraborate (MgB 4 O 7 ), which has been presented in the literature as a material for dosimetry TL, was investigated in this work. As there are no reports on the structural characterization of this material or regarding to its applicability on OSL dosimetry, the proposal of the present work was to develop compounds based on MgB 4 O 7 , with different doping, by solid state synthesis. It was made the structural, optical, TL and OSL characterization of the compound to verify it feasibility for application on radiation dosimetry. Initially, it was determined the calcination temperature and time for MgB 4 O 7 formation, with the use of thermal analyses and x ray diffraction. The ideal calcination was found at 900 °C for 7 hours. It were produced , in powder form, the compounds: MgB 4 O 7 , MgB 4 O 7 :Dy, MgB 4 O 7 :Dy,Li, MgB 4 O 7 :Ce, MgB 4 O 7 :Ce,Li, MgB 4 O 7 :Nd and MgB 4 O 7 :Nd,Li. For TL and OSL analyses it were produced pellets sintering at 950 °C for 2 hours. The radioluminescence (RL) analyses of MgB 4 O 7 :Dy and MgB 4 O 7 :Dy,Li shows wavelength emissions at 490, 590, 670 and 760 nm. For MgB 4 O 7 :Ce and MgB 4 O 7 :Ce,Li RL was observed wide emission band in the ultraviolet region. For the MgB 4 O 7 :Nd and MgB 4 O 7 :Nd,Li RL were not observed emission from the ultraviolet to infrared. With the results obtained from

  20. 29 CFR 2520.104b-4 - Alternative methods of compliance for furnishing the summary plan description and summaries of...

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 9 2010-07-01 2010-07-01 false Alternative methods of compliance for furnishing the summary plan description and summaries of material modifications of a pension plan to a retired participant, a separated participant with vested benefits, and a beneficiary receiving benefits. 2520.104b-4 Section 2520.104b-4 Labor Regulations Relating to...

  1. Thermoelastic properties of ScB2, TiB2, YB4 and HoB4

    DEFF Research Database (Denmark)

    Waskowska, A.; Gerward, L.; Staun Olsen, J.

    2011-01-01

    (4)GPa). No pressure-induced phase transformations are observed in any of the above borides up to about 20GPa. A continuous temperature-driven orthorhombic distortion is observed for HoB4 below 285K. Values of the thermal expansion coefficient are reported for ScB2 and HoB4 at 293, 200 and 100K...

  2. Association between the clinical classification of hypothyroidism and reduced TSH in LT4 supplemental replacement treatment for pregnancy in China.

    Science.gov (United States)

    Zhang, Lyu; Zhang, Zhaoyun; Ye, Hongying; Zhu, Xiaoming; Li, Yiming

    2016-01-01

    The study was aimed to evaluate the effects of levothyroxine (LT4) supplemental replacement treatment for pregnancy and analyze the associations between the clinical classification of hypothyroidism and reduced thyroid-stimulating hormone (TSH) in LT4 therapy. Totally, 195 pregnant women with hypothyroidism receiving routine prenatal care were enrolled. They were categorized into three groups: overt hypothyroidism (OH), subclinical hypothyroidism (SCH) with negative thyroperoxidase antibody (TPOAb), and SCH with positive TPOAb. The association between the clinical classification and reduced TSH in LT4 supplemental replacement treatment was assessed. The results indicated that reduced TSH was significantly different among the groups according to the clinical classifications (p = 0.043). The result was also significantly different between patients with OH and patients with SCH and negative TPOAb (p = 0.036). Similar result was reported for the comparison between patients with OH and patients with SCH and positive TPOAb (p = 0.016). Multiple variable analyses showed that LT4 supplementation, gestational age and the variable of clinical classifications were associated with reduced TSH independently. Our data suggested that the therapeutic effect of substitutive treatment with LT4 was significantly associated with different clinical classifications of hypothyroidism in pregnancy and the treatment should begin as soon as possible after diagnosis.

  3. Down-Regulation of Neuregulin1/ErbB4 Signaling in the Hippocampus Is Critical for Learning and Memory.

    Science.gov (United States)

    Tian, Jia; Geng, Fei; Gao, Feng; Chen, Yi-Hua; Liu, Ji-Hong; Wu, Jian-Lin; Lan, Yu-Jie; Zeng, Yuan-Ning; Li, Xiao-Wen; Yang, Jian-Ming; Gao, Tian-Ming

    2017-08-01

    Hippocampal function is important for learning and memory, and dysfunction of the hippocampus has been linked to the pathophysiology of neuropsychiatric diseases such as schizophrenia. Neuregulin1 (NRG1) and ErbB4, two susceptibility genes for schizophrenia, reportedly modulate long-term potentiation (LTP) at hippocampal Schaffer collateral (SC)-CA1 synapses. However, little is known regarding the contribution of hippocampal NRG1/ErbB4 signaling to learning and memory function. Here, quantitative real-time PCR and Western blotting were used to assess the mRNA and protein levels of NRG1 and ErbB4. Pharmacological and genetic approaches were used to manipulate NRG1/ErbB4 signaling, following which learning and memory behaviors were evaluated using the Morris water maze, Y-maze test, and the novel object recognition test. Spatial learning was found to reduce hippocampal NRG1 and ErbB4 expression. The blockade of NRG1/ErbB4 signaling in hippocampal CA1, either by neutralizing endogenous NRG1 or inhibiting/ablating ErbB4 receptor activity, enhanced hippocampus-dependent spatial learning, spatial working memory, and novel object recognition memory. Accordingly, administration of exogenous NRG1 impaired those functions. More importantly, the specific ablation of ErbB4 in parvalbumin interneurons also improved learning and memory performance. The manipulation of NRG1/ErbB4 signaling in the present study revealed that NRG1/ErbB4 activity in the hippocampus is critical for learning and memory. These findings might provide novel insights on the pathophysiological mechanisms of schizophrenia and a new target for the treatment of Alzheimer's disease, which is characterized by a progressive decline in cognitive function.

  4. The leukotriene B{sub 4} receptor, BLT1, is required for the induction of experimental autoimmune encephalomyelitis

    Energy Technology Data Exchange (ETDEWEB)

    Kihara, Yasuyuki, E-mail: kihara-yasuyuki@umin.net [Department of Biochemistry and Molecular Biology, Faculty of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Yokomizo, Takehiko [Department of Medical Biochemistry, Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582 (Japan); Core Research for Embryonic Science and Technology (CREST), Japan Science and Technology Agency (Japan); Kunita, Akiko; Morishita, Yasuyuki; Fukayama, Masashi [Department of Pathology, Graduate School of Medicine, The University of Tokyo, Tokyo 113-0033 (Japan); Ishii, Satoshi; Shimizu, Takao [Department of Biochemistry and Molecular Biology, Faculty of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan)

    2010-04-09

    Leukotriene B{sub 4} (LTB{sub 4}) is a potent chemoattractant and activator of neutrophils, macrophages and T cells. These cells are a key component of inflammation and all express BLT1, a high affinity G-protein-coupled receptor for LTB{sub 4}. However, little is known about the neuroimmune functions of BLT1. In this study, we describe a distinct role for BLT1 in the pathology of experimental autoimmune encephalomyelitis (EAE) and T{sub H}1/T{sub H}17 immune responses. BLT1 mRNA was highly upregulated in the spinal cord of EAE mice, especially during the induction phase. BLT1{sup -/-} mice had delayed onset and less severe symptoms of EAE than BLT1{sup +/+} mice. Additionally, inflammatory cells were recruited to the spinal cord of asymptomatic BLT1{sup +/+}, but not BLT1{sup -/-} mice before the onset of disease. Ex vivo studies showed that both the proliferation and the production of IFN-{gamma}, TNF-{alpha}, IL-17 and IL-6 were impaired in BLT1{sup -/-} cells, as compared with BLT1{sup +/+} cells. Thus, we suggest that BLT1 exacerbates EAE by regulating the migration of inflammatory cells and T{sub H}1/T{sub H}17 immune responses. Our findings provide a novel therapeutic option for the treatment of multiple sclerosis and other T{sub H}17-mediated diseases.

  5. Tissue distribution of a leukotriene antagonist 14C-LY170680, following inhalation exposure in the rat

    International Nuclear Information System (INIS)

    Pohland, R.C.; Beck, J.M.; Carlson, K.H.; Herman, D.R.; Hoppes, J.L.; Vavrek, M.T.; Wolff, R.K.

    1991-01-01

    Dissection and whole-body autoradiographic techniques were used to determine the tissue distribution profile of a leukotriene antagonist, 14 C-LY170680, following nose-only inhalation exposure in the rat. Liquid scintillation spectrometry and whole-body autoradiography indicated that highest concentrations of radiocarbon were present in stomach and small intestine at all time points. Radiocarbon reached maximum levels in stomach (2,259 ng-eq/g) and small intestine (2,399 ng-eq/g) 2 to 4 hours postexposure, respectively, and declined with time. In contrast, maximum radiocarbon concentrations in the head (146 ng-eq/g), trachea (408 ng-eq/g), and lung (534 ng-eq/g) occurred at 0 hours postexposure and steadily declined with time. Low concentrations of radiocarbon were detected in the liver ( 14 C-LY170680 were deposited in the head and within the lung following inhalation exposure. However, higher levels of radiocarbon present in the stomach and small intestine suggested significant nasal deposition followed by rapid clearance and ingestion of inhaled radioactive material. Distribution of radiocarbon limited to the respiratory and gastrointestinal tracts demonstrated minimal systemic absorption and exposure over the time course of this study

  6. Clinical evaluation of leukotriene receptor antagonists in preventing common cold-like symptoms in bronchial asthma patients.

    Science.gov (United States)

    Horiguchi, Takahiko; Ohira, Daisuke; Kobayashi, Kashin; Hirose, Masahiro; Miyazaki, Junichi; Kondo, Rieko; Tachikawa, Soichi

    2007-09-01

    We investigated the possibility of preventing common cold-like symptoms as a previously unknown benefit of leukotriene receptor antagonists (LTRAs). A total of 279 adult patients with bronchial asthma referred to our hospital between June and December 2004 were retrospectively analyzed. Patients were divided into LTRA treated and untreated groups. Frequency of acute exacerbations and number of visits to emergency rooms and of hospital admissions were analyzed as indicators of frequency of infections and asthma exacerbation over the previous 12 months. Irrespective of inhaled corticosteroid (ICS) use, frequency of infections was significantly lower in the LTRA treated group (0.3 +/- 0.7 times/year) than in the LTRA untreated group (1.6 +/- 4.2 times/year) (P cold-like symptoms. Frequency of acute exacerbations and number of hospital admissions were significantly lower in the LTRA treated versus LTRA untreated group (0.4 +/- 0.8 versus 2.7 +/- 4.3 times/year and 0.0 +/- 0.2 versus 0.4 +/- 0.7 times/year, respectively; both P cold-like symptoms than those not receiving LTRAs. LTRAs play an important role in reducing the incidence of common cold-like symptoms among asthma patients and in suppressing exacerbation of asthma symptoms possibly associated with these symptoms.

  7. Exhaled breath condensate pH and cysteinyl leukotriens in patients with chronic cough secondary to acid gastroesophageal reflux.

    Science.gov (United States)

    Heffler, Enrico; Crimi, Claudia; Brussino, Luisa; Nicola, Stefania; Sichili, Stefania; Dughera, Luca; Rolla, Giovanni; Crimi, Nunzio

    2016-12-22

    Chronic cough is one of the most common clinical problems and it may be secondary to different stimuli and diseases, including low-level physical and chemical stimulation of the esophageal-bronchial reflex, suggestive of cough-reflex hyperresponsiveness, in patients with gastroesophageal reflux; however, it is still debated whether gastroesophageal reflux could induce airway inflammation and acidification. The aim of this study was to investigate airway pH and cysteynil-leukotrienes (Cys-LTs) concentration (a marker of airway inflammation) in exhaled breath condensate (EBC). Patients with chronic cough and for which all known causes, excluding gastroesophageal reflux, had been investigated and ruled out, were enrolled in the study. All patients underwent 24 h pH monitoring, and EBC was collected to assess pH and Cys-LTs concentration. Forty-five patients were included in the study and those with gastroesophageal reflux had significantly lower EBC-pH and higher concentration of EBC-Cys-LTs. There was a linear inverse correlation between EBC-pH values and EBC-Cys-LTs logarithmically transformed, and a multivariate analysis confirmed that the only significant determinat variable of EBC-Cys-LTs was the presence of gastroesophageal reflux. This study adds knowledge on possible mechanisms related to chronic cough associated with gastroesophageal reflux, which seems to be strictly dependent on airway acidification and the production of Cys-LTs, therefore suggesting an underlying neurogenic inflammation with tachykinins involvement.

  8. An estimation of uncertainties in containment P/T analysis using CONTEMPT/LT code

    International Nuclear Information System (INIS)

    Kang, Y.M.; Park, G.C.; Lee, U.C.; Kang, C.S.

    1991-01-01

    In a nuclear power plant, the containment design pressure and temperature (P/T) have been established based on the unrealistic conservatism with suffering from a drawback in the economics. Thus, it is necessary that the uncertainties of design P/T values have to be well defined through an extensive uncertainty analysis with plant-specific input data and or models used in the computer code. This study is to estimate plant-specific uncertainties of containment design P/T using the Monte Carlo method in Kori-3 reactor. Kori-3 plant parameters and Uchida heat transfer coefficient are selected to be treated statistically after the sensitivity study. The Monte Carlo analysis has performed based on the response surface method with the CONTEMPT/LT code and Latin Hypercube sampling technique. Finally, the design values based on 95 %/95 % probability are compared with worst estimated values to assess the design margin. (author)

  9. Inducible pathway is required for mutagenesis in Salmonella typhimurium LT2

    International Nuclear Information System (INIS)

    Orrego, C.; Eisenstadt, E.

    1987-01-01

    UV mutability of Salmonella typhimurium LT2 was eliminated in the presence of a multicopy plasmid carrying the Escherichia coli lexA + gene. This result suggests that inducible, SOS-like functions are required for UV mutagenesis in S. typhimurium. S. typhimurium strains carrying either point or deletion mutations in topA had previously been shown to lose their mutability by UV or methyl methanesulfonate. Mitomycin C induction of the Phi(mucB'-lacZ') fusion (a DNA damage-inducible locus carried on plasmid pSE205) in S. typhimurium topA was normal, suggesting that RecA is activated in topA mutants. These observations lead the authors deduce that S. typhimurium has at least one DNA damage-inducible locus in addition to recA that is required for UV mutability

  10. Experimental plans for LMFBR cavity liner sodium spill test LT-1

    International Nuclear Information System (INIS)

    Hilliard, R.K.; Newell, G.A.

    1976-01-01

    Reinforced concrete is an important material of construction in LMFBR cavities and cells. Steel liners are often installed on the concrete surfaces to provide a gastight seal for minimizing air inleakage to inerted cell atmospheres and to protect the concrete from direct contact with sodium in the event of a sodium spill. In making safety assessment analyses, it is of interest to determine the adequacy of the liners to maintain their leaktightness during postulated accidents involving large sodium spills. However, data for basing analytical assessments of cell liners are very meager and an experimental program is underway at HEDL to provide some of the needed information. The HEDL cell liner evaluation program consists of both bench-scale feature tests and large-scale sodium spill demonstration tests. The plans for the first large-scale sodium spill test (LT-1) are the subject of this paper

  11. Quantum-well exciton dipolar interaction: Polarization-dependence and Z-LT splitting

    International Nuclear Information System (INIS)

    Nguyen Ba An.

    1996-12-01

    We calculate the exciton dipolar interaction in a semiconductor quantum well. The explicit polarization-dependence, i.e, the dependence on both the exciton dipole moment μ-vector and its inplane wavevector k-vector is derived. The obtained results for the three modes (L, T and Z modes) of the long-range part of the dipolar interaction satisfy the polarization sum rule for any parameters. In the long wavelength limit there is a Z-LT splitting which decreases as the well width increases reflecting a crossover from strict 2D to quasi-2D. A rough crossover from quasi-2D to 3D is also described. (author). 18 refs, 4 figs

  12. Käyttäjien tuottama sisältö markkinoinnissa : Opas

    OpenAIRE

    Koskenseppä, Mikko

    2016-01-01

    Markkinoijien ja kuluttajien roolit ovat muuttunut 2000-luvun aikana, jonka takia yritykset eivät voi enää pitää markkinointia yksisuuntaisena viestintänä. Nykyään yrityksien pitää saada kuluttajat mukaan markkinointiin, ja käyttäjien tuottama sisältö onkin yksi ratkaisu tähän ongelmaan. Tämä opinnäytetyö oli toiminnallinen työ. Sen tavoitteena oli luoda ohjeistus käyttäjien tuottaman sisällön käyttämisestä markkinoinnissa. Työn muut tavoitteet oli selvittää sen tuomat hyödyt ja ominaisuu...

  13. AutoCAD 2012 and AutoCAD LT 2012 Bible

    CERN Document Server

    Finkelstein, Ellen

    2011-01-01

    The latest version of this perennial favorite, in-depth, reference-tutorial This top-selling book has been updated by AutoCAD guru and author Ellen Finkelstein to provide you with the very latest coverage of both AutoCAD 2012 and AutoCAD LT 2012. It begins with a Quick Start tutorial, so you start creating right away. From there, the book covers so much in-depth material on AutoCAD that it is said that even Autodesk employees keep this comprehensive book at their desks. A DVD is included that features before-and-after drawings of all the tutorials and plenty of great examples from AutoCAD prof

  14. CODEX-B4C experiment. Core degradation test with boron carbide control rod

    Energy Technology Data Exchange (ETDEWEB)

    Hozer, Z; Nagy, I; Windberg, P; Balasko, M; Matus, L; Prokopiev, O; Pinter, A; Horvath, M; Gyenes, Gy [KFKI Atomic Energy Research Institute, Budapest (Hungary); Czitrovszky, A; Nagy, A; Jani, P [Research Institute for Solid State Physics and Optics, Budapest (Hungary)

    2003-11-01

    The CODEX-B4C bundle test has been successfully performed on 25{sup th} May 2001 in the framework of the COLOSS project of the EU 5{sup th} FWP. The high temperature degradation of a VVER-1000 type bundle with B{sub 4}C control rod was investigated with electrically heated fuel rods. The experiment was carried out according to a scenario selected in favour of methane formation. Degradation of control rod and fuel bundle took place at temperatures {approx}2000 deg C, cooling down of the bundle was performed in steam atmosphere. The gas composition measurement indicated no methane production during the experiment. High release of aerosols was detected in the high temperature oxidation phase. The on-line measured data are collected into a database and are available for code validation and development. (author)

  15. Production of fumonisins B2 and B4 in Tolypocladium species

    DEFF Research Database (Denmark)

    Mogensen, Jesper Mølgaard; Møller, Kirsten Amalie; von Freiesleben, Pernille

    2011-01-01

    Tolypocladium inflatum is known primarily for its production of the cyclosporines that are used as an immunosuppressive drug. However, we report here the production of the carcinogenic fumonisins B2 and B4 by this biotechnologically relevant fungal genus. These mycotoxins were detected in 11...... strains tested from three species: Tolypocladium inflatum, T. cylindrosporum, and T. geodes. Production of fumonisins by Fusarium spp. and Aspergillus niger is highly medium- and temperature-dependent, so the effect of these parameters on fumonisin production by three T. inflatum strains was studied....... Maximum production was achieved on media with high sugar content incubated at 25–30°C. Since these results demonstrate that fumonisin production could be widespread within the genus Tolypocladium, the potential contamination of commercial cyclosporine preparations with fumonisins needs to be investigated....

  16. Electrochemistry in molten borates (Na2B4O7). Electroanalytical study of oxidoreducing systems

    International Nuclear Information System (INIS)

    Gregori de Pinochet, Ida de

    1978-01-01

    The results of a study developing suitable electroanalytical means of investigation such as linear sweep voltametry and chronopotentiometry in molten borates are described. It has been shown that the reduction of U (VI) to U (V) proceeds reversibly at a platinum electrode. The diffusion coefficient for the U (VI) species at 800 0 C and the activation energy of diffusion are respectively 4 10 -7 cm 2 s -1 and (34,8+-0,8) k cal mol -1 . UO 2 is an insoluble oxide in this fused salt. Electrochemical studies of As (V) and Cu (II) show a two step reduction process at a platinum electrode. According to the solvent system definitions, the 'acid-base' equilibrium B 4 O 7 2- reversible 2 BO 2 - + B 2 O 3 is characterised at 820 0 C by the constant Ksub(D)=10sup(0,4)molsup(3)kgsup(-3) estimated by potentiometric study at a boron electrode [fr

  17. Ceramic composite resistors of B4C modified by TIO2 and glass phase

    International Nuclear Information System (INIS)

    Klimiec, E.; Zaraska, W.; Stobiecki, T.

    1998-01-01

    Technical progress in the manufacturing technology of composite materials resulted in arising of new generation of bulk resistors, resistant to high levels of overloads and high temperature. These resistors can be applied in extremely heavy working conditions, for instance in cooperation with ignition circuits. The resistors investigated in our research were performed on the basis of ceramic composite consisted of semiconductor boron carbide B 4 C as conductive phase, aluminium oxide Al 2 O 3 and non-alkali glass as insulators and titanium dioxide TiO 2 . The technological procedure of the fabrication of resistors and the results of the tests, such as temperature dependence of the electrical resistance exploitation trials, are presented. (author)

  18. Optimization of laser cladding of cold spray coatings with B4C and Ni powders

    Science.gov (United States)

    Fomin, V. M.; Golyshev, A. A.; Malikov, A. G.; Orishich, A. M.; Filippov, A. A.; Ryashin, N. S.

    2017-12-01

    In the present work, a combined method is considered for the production of a metal-matrix composite coating based on Ni and B4C. The coating is created by consistently applied methods: cold spray and laser cladding. The conditions of obtaining cermet layers are investigated depending on the parameters of laser cladding and cold spray. It is shown that the laser track structure significantly changes in accordance to the size of ceramic particles ranging 3-75 µm and its concentration. It is shown that the most perspective layers for additive manufacturing could be obtain from cold spray coatings with ceramic concentrations more than 50% by weight treated in the heat-conductivity laser mode.

  19. B4C solid target boronization of the MST reversed-field pinch

    International Nuclear Information System (INIS)

    Den Hartog, D.J.; Cekic, M.; Fiksel, G.; Hokin, S.A.; Kendrick, R.D.; Prager, S.C.; Stoneking, M.R.

    1992-10-01

    A solid rod of hot-pressed boron carbide is being used as the source of boron during boronization of MST. The most striking result of this procedure is the reduction in oxygen contamination of the plasma (O III radiation, characteristic of oxygen at the edge, falls by about a factor of 3 after boronization.). The radiated power fraction drops to about half its initial value. Particle reflux from the wall is also lowered, making density control simpler. The rod (12.7 mm diameter) is inserted into the edge plasma of normal high-power RFP discharges. B 4 C is ablated from the surface of the rod and deposited in a thin film (a-B/C:H) on the walls and limiters. The energy flux carried by ''superthermal'' (not ''runaway'') electrons at the edge of MST appears to enhance the efficient, non-destructive ablation of the boron carbide rod

  20. Moessbauer spectroscopy in nanocrystalline Fe88Zr7B4Cu1

    International Nuclear Information System (INIS)

    Navarro, I.

    1995-01-01

    Local structural changes during the crystallization process of initially amorphous Fe 88 Zr 7 B 4 Cu 1 (at %) have been investigated by means of Moessbauer spectroscopy at room temperature. In the as-cast state, no ferromagnetic phase has been detected. The crystallization process has been found to consist of two steps. In the first step (after annealing up to 500-650 C), precipitation of α-Fe (47-59%) takes place. The remaining amorphous matrix evolves to a ferromagnetic phase, although a small fraction of non-ferromagnetic phase (5-8%) is also detected during the crystallization process. Annealing at more elevated temperatures completely crystallizes the amorphous phase and three new crystalline subspectra are found. Correlations between the soft magnetic properties and these local structural changes are also discussed. ((orig.))

  1. Optically stimulated luminescence (OSL) from Ag-doped Li2B4O7 crystals

    International Nuclear Information System (INIS)

    Kananen, B.E.; Maniego, E.S.; Golden, E.M.; Giles, N.C.; McClory, J.W.; Adamiv, V.T.; Burak, Ya.V.; Halliburton, L.E.

    2016-01-01

    Optically stimulated luminescence (CW-OSL) is observed from Ag-doped lithium tetraborate (Li 2 B 4 O 7 ) crystals. Photoluminescence, optical absorption, and electron paramagnetic resonance (EPR) are used to identify the defects participating in the OSL process. As-grown crystals have Ag + ions substituting for Li + ions. They also have Ag + ions occupying interstitial sites. During a room-temperature exposure to ionizing radiation, holes are trapped at the Ag + ions that replace Li + ions and electrons are trapped at the interstitial Ag + ions, i.e., the radiation forms Ag 2+ (4d 9 ) ions and Ag 0 (4d 10 5s 1 ) atoms. These Ag 2+ and Ag 0 centers have characteristic EPR spectra. The Ag 0 centers also have a broad optical absorption band peaking near 370 nm. An OSL response is observed when the stimulation wavelength overlaps this absorption band. Specifically, stimulation with 400 nm light produces an intense OSL response when emission is monitored near 270 nm. Electrons optically released from the Ag 0 centers recombine with holes trapped at Ag 2+ ions to produce the ultraviolet emission. The OSL response is progressively smaller as the stimulation light is moved to longer wavelengths (i.e., away from the 370 nm peak of the absorption band of the Ag 0 electron traps). Oxygen vacancies are also present in the Ag-doped Li 2 B 4 O 7 crystals, and their role in the OSL process as a secondary relatively short-lived electron trap is described.

  2. Mechanical, Electronic and Optical Properties of Two Phases of NbB4: First-Principles Calculations

    Science.gov (United States)

    Yang, Ruike; Ma, Shaowei; Wei, Qun; Zhang, Dongyun

    2018-05-01

    As transition metal borides have been successfully synthesised, the study of the combination of transition metal and boron is another effective way to investigate the properties of boride. We have predicted the novel phase Amm2-NbB4. Using the Cambridge Serial Total Energy Package (CASTEP) code, we further researched on the mechanical, electronic and optical properties of C2/c- and Amm2-NbB4. It is found that both the phases of NbB4 are dynamically and mechanically stable at 0 and 100 GPa. Their Vickers hardness values are both 34 GPa, which indicate that they are hard materials. The band gap of C2/c-NbB4 is 0.145 eV, which indicates that it is a semiconductor (or metalloid) at 0 GPa. For the Amm2-NbB4, the band structure without band gap indicates it is a metal at 0 GPa. The optical properties of these two structures are similar. At 0 eV, the real part of dielectric function is 28.8 for C2/c-NbB4, and the real part value for Amm2-NbB4 is 43. We hope our work will provide some help to the experimental work about the technology of the material.

  3. Thermoluminescence and radioluminescence properties of tissue equivalent Cu-doped Li2B4O7 for radiation dosimetry

    International Nuclear Information System (INIS)

    Cruz Z, E.; Furetta, C.; Marcazzo, J.; Santiago, M.; Guarneros, C.; Pacio, M.; Palomino, R.

    2015-10-01

    Thermoluminescence (Tl) and radioluminescence (Rl) properties of lithium tetraborate (Li 2 B 4 O 7 ) doped with different concentration of copper (0.25, 0.5, 1 wt %) under gamma and beta irradiation has been investigated. The feasibility of using this borate in radiation dosimetry at low doses has been evaluated. Tissue equivalent Li 2 B 4 O 7 was prepared by solid state reaction using mixing stoichiometric compositions of lithium carbonate (Li 2 CO 3 ) and boric acid (H 3 BO 3 ) and a solution of CuCl 2 as dopant. The glow curve, of the most efficient copper doped borate (Li 2 B 4 O 7 :Cu 0.5 wt %), shows a main stable peak centered at 225 degrees C and a second low temperature peak centered at 80 degrees C. The low temperature peak disappears completely after 24 hours of storage in darkness and at room temperature or after an annealing at 120 degrees C for 10 seconds. The main peak of the Li 2 B 4 O 7 :Cu remains constant. The Tl response of Li 2 B 4 O 7 :Cu shows good linearity in the analyzed dose range. The stability and repeatability of Rl signals of the borate have been studied and the Li 2 B 4 O 7 :Cu (0.5 wt %) shown the higher Rl emission and a stable and repetitive response. Results show that Li 2 B 4 O 7 :Cu has prospects to be used in gamma and beta radiation dosimetry. (Author)

  4. A new avian fauna from the early-middle Eocene Lillebælt Clay Formation of Denmark

    DEFF Research Database (Denmark)

    Lindow, Bent Erik Kramer

    A number of hitherto undescribed fossil bird remains have been recovered from the Lillebælt Clay Formation of central Denmark, which is early-middle Eocene in age (~50 to 43 mya). The core of the material consists of fossils acquired through the Danish ‘Danekræ' fossil treasure trove legislation......, a member of the extinct 'pseudo-toothed birds' and the first representative of this group known from Denmark. Other taxa present include remains of Lithornithidae and a new taxon possessing a massive, psittacid-like beak. The Lillebælt Clay Formation birds are temporally placed just after the Early Eocene...

  5. Microstructural evolution and mechanical properties of Mg composites containing nano-B4C hybridized micro-Ti particulates

    International Nuclear Information System (INIS)

    Sankaranarayanan, S.; Sabat, R.K.; Jayalakshmi, S.; Suwas, S.; Gupta, M.

    2014-01-01

    In this work, the microstructural evolution and mechanical properties of extruded Mg composites containing micro-Ti particulates hybridized with varying contents of nano-B 4 C are investigated, and compared with Mg-5.6Ti. Microstructural characterization showed the presence of uniformly distributed micro-Ti particles embedded with nano-B 4 C particulates that resulted in significant grain refinement. Electron back scattered diffraction (EBSD) analyses of Mg-(5.6Ti + x-B 4 C) BM hybrid composites showed that the addition of hybridized particle resulted in relatively more recrystallized grains, realignment of basal planes and extension of weak basal fibre texture when compared to Mg-5.6Ti. The evaluation of mechanical properties indicated improved strength with ductility retention in Mg-(5.6Ti + x-B 4 C) BM hybrid composites. When compared to Mg-5.6Ti, the superior strength properties of the Mg-(5.6Ti + x-B 4 C) BM hybrid composites are attributed to the presence of nano-reinforcements, the uniform distribution of the hybridized particles, better interfacial bonding between the matrix and the reinforcement particles and the matrix grain refinement achieved by nano-B 4 C addition. The ductility enhancement obtained in hybrid composites can be attributed to the fibre texture spread and favourable basal plane orientation achieved due to nano B 4 C addition. - Highlights: • Micro-Ti particulates are hybridized with varying weight fractions of nano-B 4 C. • The hybrid mixture was used as hybrid reinforcements in magnesium. • Microstructure and mechanical properties of Mg-(5.6Ti + x-B 4 C) BM are compared with Mg-5.6Ti. • Electron back scattered diffraction (EBSD) analysis conducted to study the microtexture evolution

  6. Comparison of microstructural and mechanical properties of Al–TiC, Al–B4C and Al–TiC–B4C composites prepared by casting techniques

    International Nuclear Information System (INIS)

    Mazaheri, Y.; Meratian, M.; Emadi, R.; Najarian, A.R.

    2013-01-01

    In the present work, production of Al–10%TiC, Al–10% B 4 C, Al–5%TiC–5%B 4 C (volume fraction) composites by casting techniques were studied. However, casting techniques suffers from poor incorporation and distribution of the reinforcement particles in the matrix. These problems become especially significant as the reinforcement size decreases due to greater agglomeration tendency and reduced wettability of the particles with the melt. Microstructure characterization of the composite samples was investigated by using scanning electron microscopy (SEM) equipped with energy dispersive spectroscopy (EDS) and X-ray diffractometer (XRD).The results showed heat treatment of B 4 C particles and addition of TiC particles with the flux improved the wettability and incorporation of reinforcement particles into melt. Mechanical characterization of samples showed that maximum hardness had belonged to Al–5%TiC–5%B 4 C composite, maximum yield and tensile strength had belonged to Al–10%B 4 C composite and maximum elongation had belonged to Al–10%TiC composite. Furthermore, wear properties of composites revealed the better behavior for Al–B 4 C composite.

  7. First-principles study of elastic and thermodynamic properties of orthorhombic OsB4 under high pressure

    Science.gov (United States)

    Yan, Hai-Yan; Zhang, Mei-Guang; Huang, Duo-Hui; Wei, Qun

    2013-04-01

    The first-principles study on the elastic properties, elastic anisotropy and thermodynamic properties of the orthorhombic OsB4 is reported using density functional theory method with the ultrasoft pseudopotential scheme in the frame of the generalized gradient approximation. The calculated equilibrium parameters are in good agreement with the available theoretical data. A complete elastic tensor and crystal anisotropies of the ultra-incompressible OsB4 are determined in the pressure range of 0-50 GPa. By the elastic stability criteria, it is predicted that the orthorhombic OsB4 is stable below 50 GPa. By using the quasi-harmonic Debye model, the heat capacity, the coefficient of thermal expansion, and the Grüneisen parameter of OsB4 are also successfully obtained in the present work.

  8. The effect of anti-IgE treatment on in vitro leukotriene release in children with seasonal allergic rhinitis.

    Science.gov (United States)

    Kopp, Matthias Volkmar; Brauburger, Jens; Riedinger, Frank; Beischer, Dorothee; Ihorst, Gabriele; Kamin, Wolfgang; Zielen, Stefan; Bez; Friedrichs, Frank; Von Berg, Andrea; Gerhold, Kerstin; Hamelmann, Eckard; Hultsch; Kuehr, Joachim

    2002-11-01

    Binding of allergens with IgE to the IgE receptors on mast cells and basophils results in the release of inflammatory mediators as sulfidoleukotrienes (SLTs), triggering allergic cascades that result in allergic symptoms, such as asthma and rhinitis. We sought to investigate whether anti-IgE (Oma-lizumab), a humanized monoclonal anti-IgE antibody, in addition to specific immunotherapy (SIT) affects the leukotriene pathway. Ninety-two children (age range, 6-17 years) with sensitization to birch and grass pollens and with seasonal allergic rhinitis were included in a phase III, placebo- controlled, multicenter clinical study. All subjects were randomized to one of 4 treatment groups. Two groups subcutaneously received birch SIT and 2 groups received grass SIT for at least 14 weeks before the start of the birch pollen season. After 12 weeks of SIT titration, placebo or anti-IgE was added for 24 weeks. The primary clinical efficacy variable was symptom load (ie, the sum of daily symptom severity score and rescue medication score during pollen season). Blood samples taken at baseline and at the end of study treatment after the grass pollen season were used for separation of leukocytes in this substudy. After in vitro stimulation of the blood cells with grass and birch pollen allergens, SLT release (LTC4, LTD4, and LTE4) was quantified by using the ELISA technique. Before the study treatment, SLT release to birch and grass pollen exposure did not differ significantly among the 4 groups. Under treatment with anti-IgE + SIT-grass (n = 23), a lower symptom load occurred during the pollen season compared to placebo + SIT-grass (n = 24, P =.012). The same applied to both groups receiving birch SIT (n = 23 and n = 22, respectively; P =.03). At the end of treatment, the combination of anti-IgE plus grass SIT, as well as anti-IgE plus birch SIT, resulted in significantly lower SLT release after stimulation with the corresponding allergen (416 ng/L [5th-95th percentile, 1

  9. Relationship between leukotriene-modifying agent prescriptions dispensed and rate of suicide deaths by county in the US

    Directory of Open Access Journals (Sweden)

    Schumock GT

    2011-09-01

    Full Text Available Glen T Schumock1, Robert D Gibbons2, Todd A Lee1,3,4,6, Min J Joo4, Robert J Valuck5, Leslie T Stayner61Center for Pharmacoeconomic Research, and Department of Pharmacy Practice, College of Pharmacy, University of Illinois at Chicago, Chicago, IL, USA; 2Center for Health Statistics, and Departments of Medicine and Health Studies, Pritzker School of Medicine, University of Chicago, Chicago, IL, USA; 3Center for Management of Complex Chronic Care, Hines VA Hospital, Hines, IL, USA; 4Section of Pulmonary, Critical Care, Sleep and Allergy, Department of Medicine, College of Medicine, University of Illinois at Chicago, Chicago, IL, USA; 5Department of Clinical Pharmacy, School of Pharmacy, University of Colorado, Aurora, CO, USA; 6Division of Epidemiology and Biostatistics, School of Public Health, University of Illinois at Chicago, Chicago, IL, USABackground: The US Food and Drug Administration has issued warnings about a potential link between leukotriene receptor-modifying agents (LTMA and suicide. These warnings are based on case reports and there is controversy about the association. While spontaneous reporting of suicide-related events attributed to LTMA has risen dramatically, these data may be biased by the warnings. The objective of this study was to explore the relationship between LTMA and suicide deaths using event data preceding the Food and Drug Administration warnings.Methods: We conducted a mixed-effects Poisson regression analysis of the association between LTMA prescriptions dispensed and suicide deaths at the county level. Counts of suicide deaths in each US county, stratified by race, age group, gender, and year were obtained from the National Center for Health Statistics for the period January 1, 1999 to December 31, 2006. Counts of LTMA prescriptions dispensed in each US county were obtained from IMS Health Incorporated. The model estimated the overall suicide rate conditional on LTMA use, adjusted for age, gender, race, year

  10. PSGL-1–mediated activation of EphB4 increases the proangiogenic potential of endothelial progenitor cells

    Science.gov (United States)

    Foubert, Philippe; Silvestre, Jean-Sébastien; Souttou, Boussad; Barateau, Véronique; Martin, Coralie; Ebrahimian, Téni G.; Leré-Déan, Carole; Contreres, Jean Olivier; Sulpice, Eric; Levy, Bernard I.; Plouët, Jean; Tobelem, Gérard; Le Ricousse-Roussanne, Sophie

    2007-01-01

    Endothelial progenitor cell (EPC) transplantation has beneficial effects for therapeutic neovascularization; however, only a small proportion of injected cells home to the lesion and incorporate into the neocapillaries. Consequently, this type of cell therapy requires substantial improvement to be of clinical value. Erythropoietin-producing human hepatocellular carcinoma (Eph) receptors and their ephrin ligands are key regulators of vascular development. We postulated that activation of the EphB4/ephrin-B2 system may enhance EPC proangiogenic potential. In this report, we demonstrate in a nude mouse model of hind limb ischemia that EphB4 activation with an ephrin-B2–Fc chimeric protein increases the angiogenic potential of human EPCs. This effect was abolished by EphB4 siRNA, confirming that it is mediated by EphB4. EphB4 activation enhanced P selectin glycoprotein ligand-1 (PSGL-1) expression and EPC adhesion. Inhibition of PSGL-1 by siRNA reversed the proangiogenic and adhesive effects of EphB4 activation. Moreover, neutralizing antibodies to E selectin and P selectin blocked ephrin-B2–Fc–stimulated EPC adhesion properties. Thus, activation of EphB4 enhances EPC proangiogenic capacity through induction of PSGL-1 expression and adhesion to E selectin and P selectin. Therefore, activation of EphB4 is an innovative and potentially valuable therapeutic strategy for improving the recruitment of EPCs to sites of neovascularization and thereby the efficiency of cell-based proangiogenic therapy. PMID:17510705

  11. Karzai nõuab USA-lt võitu, ähvardades muidu rahu teha / Heiki Suurkask

    Index Scriptorium Estoniae

    Suurkask, Heiki, 1972-

    2008-01-01

    Afganistani president Hamid Karzai nõuab USA-lt ajakava selle kohta, millal NATO kavatseb Talibani üle võidu saavutada. Afganistanis visiidil viibinud USA president George W. Bush avaldas toetust Barack Obama kavale keskenduda veelgi enam Afganistanis sõdimisele

  12. ’When You Get a Job to Do, Do It.’ The Airpower Leadership of Lt Gen William H. Tunner

    Science.gov (United States)

    2008-01-01

    PAGE unclassified Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std Z39-18 Air University Stephen R. Lorenz, Lt Gen, Commander Air Force Doctrine...Collier, Richard. Bridge across the Sky. New York: Mc Graw - Hill, 1978. Combined Airlift Task Force. A Report on the Airlift Berlin Mis- sion. 572.101B, 26

  13. USA kohus nõuab LHV-lt, Lepikult ja Peegilt kiiresti ligi 14 miljonit krooni / Lauri Matsulevitsh

    Index Scriptorium Estoniae

    Matsulevitsh, Lauri

    2005-01-01

    USA kohus kinnitas investeerimispangaga LHV eelkokkuleppe ning muutis esialgset hagi tagamise määrust, millega nõuab LHV-lt sealt välja viidud raha USA kohturegistri kontole tagasi viie päeva jooksul. Lisa: Kontodelt nõutakse 13,8 mln krooni. Vt. samas: Advokaat: SEC kasutab jõupositsiooni

  14. Trace fossils from the eocene Lillebælt clay formation, Røsnæs Peninsula, Denmark

    DEFF Research Database (Denmark)

    Nielsen, Jan Kresten; Milàn, Jesper; Mesfun, Daniel

    2015-01-01

    A cliff exposure of the Eocene Lillebælt Clay Formation, on the Røsnæs peninsula of Zealand, Denmark, has yielded a diverse trace-fossil assemblage. The trace fossils are described formally for the first time and assigned to Phymatoderma melvillensis, unnamed clusters of small burrows, Ophiomorpha...

  15. Analytical support for the B4C control rod test QUENCH-07

    International Nuclear Information System (INIS)

    Homann, C.; Hering, W.; Fernandez Benitez, J.A.; Ortega Bernardo, M.

    2003-04-01

    Degradation of B 4 C absorber rods during a beyond design accident in a nuclear power reactor may be a safety concern. Among others, the integral test QUENCH-07 is performed in the FZK QUENCH facility and supported by analytical work within the Euratom Fifth Framework Programme on Nuclear Fission Safety to get a more profound database. Since the test differed substantially from previous QUENCH tests, much more work had to be done for pretest calculations than usual to guarantee the safety of the facility and to derive the test protocol. Several institutions shared in this work with different computer code systems, as used for nuclear reactor safety analyses. Due to this effort, problems could be identified and solved, leading to several modifications of the originally planned test conduct, until a feasible test protocol could be derived and recommended. All calculations showed the same trends. Especially the high temperatures and hence the small safety margin for the facility were a concern. In this report, contributions of various authors, engaged in this work, are presented. The test QUENCH-07 and the related computational support by the engaged institutions were co-financed by the European Community under the Euratom Fifth Framework Programme on Nuclear Fission Safety 1998 - 2002 (COLOSS Project, contract No. FIKS-CT-1999-00002). (orig.)

  16. Fine Structure Study of the Plasma Coatings B4C-Ni-P

    Science.gov (United States)

    Kornienko, E. E.; Bezrukova, V. A.; Kuz'min, V. I.; Lozhkin, V. S.; Tutunkova, M. K.

    2017-12-01

    The article considers structure of coatings formed of the B4C-Ni-P powder. The coatings were deposited using air-plasma spraying with the unit for annular injection of powder. The pipes from steel 20 (0.2 % C) were used as a substrate. The structure and phase composition of the coatings were studied by optical microscopy, scanning electron microscopy, transmission electron microscopy and X-ray diffractometry. It is shown that high-density composite coatings consisting of boron carbide particles distributed in the nickel boride metal matrix are formed using air-plasma spraying. The areas with round inclusions characterized by the increased amount of nickel, phosphorus and boron are located around the boron carbide particles. Boron oxides and nickel oxides are also present in the coatings. Thin interlayers with amorphous-crystalline structure are formed around the boron carbide particles. The thickness of these interlayers does not exceed 1 μm. The metal matrix material represents areas with nanocrystalline structure and columnar crystals.

  17. Electrochemical Polishing Applications and EIS of a Vitamin B4-Based Ionic Liquid

    International Nuclear Information System (INIS)

    Wixtrom, Alex I.; Buhler, Jessica E.; Reece, Charles E.; Abdel-Fattah, Tarek M.

    2013-01-01

    Modern particle accelerators require minimal interior surface roughness for Niobium superconducting radio frequency (SRF) cavities. Polishing of the Nb is currently achieved via electrochemical polishing with concentrated mixtures of sulfuric and hydrofluoric acids. This acid-based approach is effective at reducing the surface roughness to acceptable levels for SRF use, but due to acid-related hazards and extra costs (including safe disposal of used polishing solutions), an acid-free method would be preferable. This study focuses on an alternative electrochemical polishing method for Nb, using a novel ionic liquid solution containing choline chloride, also known as Vitamin B 4 (VB 4 ). Potentiostatic electrochemical impedance spectroscopy (EIS) was also performed on the VB4-based system. Nb polished using the VB4-based method was found to have a final surface roughness comparable to that achieved via the acid-based method, as assessed by atomic force microscopy (AFM). These findings indicate that acid-free VB 4 -based electrochemical polishing of Nb represents a promising replacement for acid-based methods of SRF cavity preparation

  18. Sintering of B4C powder obtained by a modified carbo-thermal reaction

    International Nuclear Information System (INIS)

    Rocha, R.M.; Kazumi, M.H.; Goncalves, D.P.; Melo, F.C.L.

    2005-01-01

    Boron carbide is one of the hardest materials and a highly refractory material that is of great interest for structural, electronic and nuclear applications. B 4 C is commercially manufactured by the carbo-thermal reduction of a mixture of boron oxide (B 2 O 3 ) in an batch electric arc furnace process. However the carbo-thermal reaction on the stoichiometric starting composition results an excess carbon residue because of the boron loss in the form of B 2 O 2 . Thus, a modified carbo-thermal reaction is applied with an excess B 2 O 3 to compensate the loss and to obtain stoichiometric powders. The aim of this work is to study the sinterability of this powder with the lower carbon residue acting as sintering additive. Pressureless sintering in the temperatures of 1900 deg. C/30 min and 2100 deg. C/30 min in argon atmosphere were applied. The synthesized powders were analysed by XRD and SEM. Density of 94% of theoretical density was achieved for sample prepared with the powder obtained with 50% B 2 O 3 excess synthesized at 1700 deg. C/15 min. (authors)

  19. Dynamic ErbB4 Activity in Hippocampal-Prefrontal Synchrony and Top-Down Attention in Rodents.

    Science.gov (United States)

    Tan, Zhibing; Robinson, Heath L; Yin, Dong-Min; Liu, Yu; Liu, Fang; Wang, Hongsheng; Lin, Thiri W; Xing, Guanglin; Gan, Lin; Xiong, Wen-Cheng; Mei, Lin

    2018-04-18

    Top-down attention is crucial for meaningful behaviors and impaired in various mental disorders. However, its underpinning regulatory mechanisms are poorly understood. We demonstrate that the hippocampal-prefrontal synchrony associates with levels of top-down attention. Both attention and synchrony are reduced in mutant mice of ErbB4, a receptor of neuregulin-1. We used chemical genetic and optogenetic approaches to inactivate ErbB4 kinase and ErbB4+ interneurons, respectively, both of which reduce gamma-aminobutyric acid (GABA) activity. Such inhibitions in the hippocampus impair both hippocampal-prefrontal synchrony and top-down attention, whereas those in the prefrontal cortex alter attention, but not synchrony. These observations identify a role of ErbB4-dependent GABA activity in the hippocampus in synchronizing the hippocampal-prefrontal pathway and demonstrate that acute, dynamic ErbB4 signaling is required to command top-down attention. Because both neuregulin-1 and ErbB4 are susceptibility genes of schizophrenia and major depression, our study contributes to a better understanding of these disorders. VIDEO ABSTRACT. Copyright © 2018 Elsevier Inc. All rights reserved.

  20. Progress on B4C control rod modeling in RELAP/SCDAPSIM with application to quench and Phebus

    International Nuclear Information System (INIS)

    Kawahara, Keisuke; Hohorst, Judith K.; Allison, Chris M.

    2014-01-01

    The RELAP/SCDAPSIM code is designed to predict the behavior of reactor systems during normal and accident conditions. RELAP/SCDAPSIM/MOD3.5 is an experimental version of the code with the most advanced fuel and severe accident behavior models and correlations. It includes modeling improvements that were specifically added to support (a) the ongoing experimental severe accident programs in Europe and Japan and (b) the analysis and assessment activities related to the accident at the Fukushima Daiichi NPS. One of the improved models describes the behavior of cylindrical B 4 C control rods used in selected PWR designs and in integral experiments used to assess the heating and melting of PWR, BWR, and VVER assemblies. It replaces an older model that was originally developed by the US Nuclear Regulatory Commission in the mid- 1980's. It includes a combination of new and improved models and correlations to more accurately describe (a) eutectic reactions between Zircaloy, B 4 C, and stainless steel, (b) oxidation for B 4 C, Zircaloy, and stainless steel, and (c) the effects of the gap between the Zircaloy guide tube and the stainless steel sheath surrounding B 4 C pellets used in many control rod designs. This paper will discuss the development of the new model and validation of the model using the PHEBUS B 4 C test, FPT-3, and the KIT quench experiments with a central B 4 C control rod. (authors)

  1. Cutting Edge: 2B4-Mediated Coinhibition of CD4+ T Cells Underlies Mortality in Experimental Sepsis.

    Science.gov (United States)

    Chen, Ching-Wen; Mittal, Rohit; Klingensmith, Nathan J; Burd, Eileen M; Terhorst, Cox; Martin, Greg S; Coopersmith, Craig M; Ford, Mandy L

    2017-09-15

    Sepsis is a leading cause of death in the United States, but the mechanisms underlying sepsis-induced immune dysregulation remain poorly understood. 2B4 (CD244, SLAM4) is a cosignaling molecule expressed predominantly on NK cells and memory CD8 + T cells that has been shown to regulate T cell function in models of viral infection and autoimmunity. In this article, we show that 2B4 signaling mediates sepsis lymphocyte dysfunction and mortality. 2B4 expression is increased on CD4 + T cells in septic animals and human patients at early time points. Importantly, genetic loss or pharmacologic inhibition of 2B4 significantly increased survival in a murine cecal ligation and puncture model. Further, CD4-specific conditional knockouts showed that 2B4 functions on CD4 + T cell populations in a cell-intrinsic manner and modulates adaptive and innate immune responses during sepsis. Our results illuminate a novel role for 2B4 coinhibitory signaling on CD4 + T cells in mediating immune dysregulation. Copyright © 2017 by The American Association of Immunologists, Inc.

  2. Contempt-LT: a computer program for predicting containment pressure-temperature response to a loss-of-coolant accident

    International Nuclear Information System (INIS)

    Wheat, L.L.; Wagner, R.J.; Niederauer, G.F.; Obenchain, C.F.

    1975-06-01

    CONTEMPT-LT is a digital computer program, written in FORTRAN IV, developed to describe the long-term behavior of water-cooled nuclear reactor containment systems subjected to postulated loss-of-coolant accident (LOCA) conditions. The program calculates the time variation of compartment pressures, temperatures, mass and energy inventories, heat structure temperature distributions, and energy exchange with adjacent compartments. The program is capable of describing the effects of leakage on containment response. Models are provided to describe fan cooler and cooling spray engineered safety systems. Up to four compartments can be modeled with CONTEMPT-LT, and any compartment except the reactor system may have both a liquid pool region and an air-vapor atmosphere region above the pool. Each region is assumed to have a uniform temperature, but the temperatures of the two regions may be different. CONTEMPT-LT can be used to model all current boiling water reactor pressure suppression systems, including containments with either vertical or horizontal vent systems. CONTEMPT-LT can also be used to model pressurized water reactor dry containments, subatmospheric containments, and dual volume containments with an annulus region, and can be used to describe containment responses in experimental containment systems. The program user defines which compartments are used, specifies input mass and energy additions, defines heat structure and leakage systems, and describes the time advancement and output control. CONTEMPT-LT source decks are available in double precision extended-binary-coded-decimal-interchange-code (EBCDIC) versions. Sample problems have been run on the IBM360/75 computer. (U.S.)

  3. Cloud Atlas: Rotational Modulations in the L/T Transition Brown Dwarf Companion HN Peg B

    Science.gov (United States)

    Zhou, Yifan; Apai, Dániel; Metchev, Stanimir; Lew, Ben W. P.; Schneider, Glenn; Marley, Mark S.; Karalidi, Theodora; Manjavacas, Elena; Bedin, Luigi R.; Cowan, Nicolas B.; Miles-Páez, Paulo A.; Lowrance, Patrick J.; Radigan, Jacqueline; Burgasser, Adam J.

    2018-03-01

    Time-resolved observations of brown dwarfs’ rotational modulations provide powerful insights into the properties of condensate clouds in ultra-cool atmospheres. Multi-wavelength light curves reveal cloud vertical structures, condensate particle sizes, and cloud morphology, which directly constrain condensate cloud and atmospheric circulation models. We report results from Hubble Space Telescope/Wide Field Camera 3 near-infrared G141 taken in six consecutive orbits observations of HN Peg B, an L/T transition brown dwarf companion to a G0V type star. The best-fit sine wave to the 1.1–1.7 μm broadband light curve has an amplitude of 1.206% ± 0.025% and period of 15.4 ± 0.5 hr. The modulation amplitude has no detectable wavelength dependence except in the 1.4 μm water absorption band, indicating that the characteristic condensate particle sizes are large (>1 μm). We detect significantly (4.4σ) lower modulation amplitude in the 1.4 μm water absorption band and find that HN Peg B’s spectral modulation resembles those of early T type brown dwarfs. We also describe a new empirical interpolation method to remove spectral contamination from the bright host star. This method may be applied in other high-contrast time-resolved observations with WFC3.

  4. Cloud Atlas: Rotational Modulations in the L/T Transition Brown Dwarf Companion HN Peg B

    Science.gov (United States)

    Zhou, Yifan; Apai, Daniel; Metchev, Stanimir; Lew, Ben W. P.; Schneider, Glenn; Marley, Mark S.; Karalidi, Theodora; Manjavacas, Elena; Bedin, Luigi R.; Cowan, Nicolas B.; hide

    2018-01-01

    Time-resolved observations of brown dwarfs' rotational modulations provide powerful insights into the properties of condensate clouds in ultra-cool atmospheres. Multi-wavelength light curves reveal cloud vertical structures, condensate particle sizes, and cloud morphology, which directly constrain condensate cloud and atmospheric circulation models. We report results from Hubble Space Telescope/Wide Field Camera 3 (WFC3) near-infrared G141 taken in six consecutive orbits observations of HNPeg B, an L/T transition brown dwarf companion to a G0V type star. The best-fit sine wave to the 1.1 to 1.7 micron broadband light curve has the amplitude of and period of hour. The modulation amplitude has no detectable wavelength dependence except in the 1.4 micron water absorption band, indicating that the characteristic condensate particle sizes are large (greater than 1 micron). We detect significantly (4.4 sigma) lower modulation amplitude in the 1.4 micron water absorption band, and find that HN Peg B's spectral modulation resembles those of early T type brown dwarfs. We also describe a new empirical interpolation method to remove spectral contamination from the bright host star. This method may be applied in other high-contrast time-resolved observations with WFC3.

  5. Interpretation of the CABRI LT1 test with SAS4A-code analysis

    International Nuclear Information System (INIS)

    Sato, Ikken; Onoda, Yu-uichi

    2001-03-01

    In the CABRI-FAST LT1 test, simulating a ULOF (Unprotected Loss of Flow) accident of LMFBR, pin failure took place rather early during the transient. No fuel melting is expected at this failure because the energy injection was too low and a rapid gas-release-like response leading to coolant-channel voiding was observed. This channel voiding was followed by a gradual fuel breakup and axial relocation. With an aid of SAS4A analysis, interpretation of this test was performed. Although the original SAS4A model was not well fitted to this type of early pin failure, the global behavior after the pin failure was reasonably simulated with temporary modifications. Through this study, gas release behavior from the failed fuel pin and its effect on further transient were well understood. It was also demonstrated that the SAS4A code has a potential to simulate the post-failure behavior initiated by a very early pin failure provided that necessary model modification is given. (author)

  6. An atlas of L-T transition brown dwarfs with VLT/XShooter

    Science.gov (United States)

    Marocco, F.; Day-Jones, A. C.; Jones, H. R. A.; Pinfield, D. J.

    In this contribution we present the first results from a large observing campaign we are carrying out using VLT/Xshooter to obtain spectra of a large sample (˜250 objects) of L-T transition brown dwarfs. Here we report the results based on the first ˜120 spectra already obtained. The large sample, and the wide spectral coverage (300-2480 nm) given by Xshooter, will allow us to do a new powerful analysis, at an unprecedent level. By fitting the absorption lines of a given element (e.g. Na) at different wavelengths we can test ultracool atmospheric models and draw for the first time a 3D picture of stellar atmospheres at temperatures down to 1000K. Determining the atmospheric parameters (e.g. temperature, surface gravity and metallicity) of a big sample of brown dwarfs, will allow us to understand the role of these parameters on the formation of their spectra. The large number of objects in our sample also will allow us to do a statistical significant test of the birth rate and initial mass function predictions for brown dwarfs. Determining the shape of the initial mass function for very low mass objects is a fundamental task to improve galaxy models, as recent studies tep{2010Natur.468..940V} have shown that low-mass objects dominate in massive elliptical galaxies.

  7. Ga2O3 doping and vacancy effect in KNN—LT lead-free piezoceramics

    Science.gov (United States)

    Tan, Zhi; Xing, Jie; Jiang, Laiming; Zhu, Jianguo; Wu, Bo

    2017-12-01

    Ga2O3 was doped into 0.95(K0.48Na0.52)NbO3—0.05LiTaO3 (KNN—LT) ceramics and its influences on the sintering behavior, phase structure and electrical properties of ceramics were studied. Firstly, SEM observation exhibits that more and more glass phase appears in ceramics with the gradual addition of Ga2O3, which determines the continuous decrease in sintering temperatures. And the addition of Ga2O3 is also found to increase the orthorhombic—tetragonal transition temperature ( T O—T) of system to a higher level. Secondly, both the density and the coercive field ( E C) of ceramics increase firstly and then decrease with increasing the Ga2O3 content, and the KNN—LT— xGa sample at x = 0.004 shows a pinched P— E hysteresis loop. Finally, the impedance characteristics of KNN—LT— xGa ceramics were investigated at different temperatures, revealing a typical vacancy related conduction mechanism. This work demonstrates that Ga2O3 is a good sintering aid for KNN-based ceramics, and the vacancy plays an important role in the sintering and electrical behaviors of ceramics.

  8. Studies on shallow traps in Li2B4O7:Eu,Mn

    International Nuclear Information System (INIS)

    Drozdowski, Winicjusz; Brylew, Kamil; Kaczmarek, Sławomir M.; Piwowarska, Danuta; Nakai, Yosuke; Tsuboi, Taiju; Huang, Wei

    2014-01-01

    Li 2 B 4 O 7 (LTB) single crystals doped with 0.5 mol% Mn and 0.005 mol% Eu have been grown by the Czochralski method. The presence of Eu 3+ has been confirmed by photoluminescence spectra of non-irradiated crystals, whereas the presence of Mn 2+ by absorption spectra of gamma-irradiated ones, as well as by EPR measurements. Unlike in most thermoluminescence studies on pure and doped LTB, performed usually above 300 K, glow curves have been recorded between 10 and 300 K in order to focus the attention on shallow traps. A broad, intense glow peak is observed around 80 K, with three weaker peaks at 205, 255, and 280 K. Based on supplementary T max  − T stop experiments, the trap parameters have been derived assuming that the glow curve is in fact formed by a superposition of a double Gaussian band related to a quasi-continuous distribution of trapping levels, and several glow peaks produced by discrete traps. The nature of the traps is also discussed. - Highlights: • Radioluminescence spectra of LTB:Eu,Mn have been measured at various temperatures. • Glow curves of LTB:Eu,Mn have been recorded between 10 and 300 K. • Thermoluminescence studies have been extended with the T max  − T stop method. • Trap parameters related to particular glow peaks have been derived. • Besides discrete traps a quasi-continuous distribution has been found

  9. New coxsackievirus B4 genotype circulating in Inner Mongolia Autonomous Region, China.

    Directory of Open Access Journals (Sweden)

    Xiaoling Tian

    Full Text Available Hand, foot, and mouth disease (HFMD surveillance was initiated in the Inner Mongolia Autonomous Region of China in 2007, a crucial scrutiny for monitoring the prevalence of enterovirus serotypes associated with HFMD patients. However, this surveillance mostly focused on enterovirus 71 (EV-A71 and coxsackievirus A16; therefore, information on other enterovirus serotypes is limited. To identify the other circulating enterovirus serotypes in the HFMD outbreaks in Inner Mongolia in 2010, clinical samples from HFMD patients were investigated. Six coxsackievirus B4 (CVB4 strains were isolated and phylogenetic analyses of VP1 sequences were performed. Full-length genome sequences of two representative CVB4 isolates were acquired and similarity plot and bootscanning analyses were performed. The phylogenetic dendrogram indicated that all CVB4 strains could be divided into 5 genotypes (Genotypes I-V with high bootstrap support (90-100%. The CVB4 prototype strain (JVB was the sole member of genotype I. CVB4 strains belonging to genotype II, which were once common in Europe and the Americas, seemingly disappeared and gave way to genotype III and IV strains, which appear to be the dominant circulating strains in the world. All Chinese CVB4 strains belonged to Genotype V, a newly identified genotype supported by a high bootstrap value (100%, and are circulating only in mainland of China. Intertypic recombination occurred in the Chinese CVB4 strains with novel unknown serotype EV-B donor sequences. Two Chinese CVB4 strains had a virulent residue at position 129 of VP1, and one strain also had a virulent residue at position 16 of VP4. Increased surveillance is needed to monitor the emergence of new genetic lineages of enteroviruses in areas that are often associated with large-scale outbreaks. In addition, continued monitoring of enteroviruses by clinical surveillance and genetic characterization should be enhanced.

  10. Characterization of a chitinase with antifungal activity from a native Serratia marcescens B4A

    Directory of Open Access Journals (Sweden)

    Mandana Zarei

    2011-09-01

    Full Text Available Chitinases have the ability of chitin digestion that constitutes a main compound of the cell wall in many of the phytopathogens such as fungi. In the following investigation, a novel chitinase with antifungal activity was characterized from a native Serratia marcescens B4A. Partially purified enzyme had an apparent molecular mass of 54 kDa. It indicated an optimum activity in pH 5 at 45ºC. Enzyme was stable in 55ºC for 20 min and at a pH range of 3-9 for 90 min at 25ºC. When the temperature was raised to 60ºC, it might affect the structure of enzymes lead to reduction of chitinase activity. Moreover, the Km and Vmax values for chitin were 8.3 mg/ml and 2.4 mmol/min, respectively. Additionally, the effect of some cations and chemical compounds were found to stimulate the chitinase activity. In addition, Iodoacetamide and Idoacetic acid did not inhibit enzyme activity, indicating that cysteine residues are not part of the catalytic site of chitinase. Finally, chitinase activity was further monitored by scanning electronic microscopy data in which progressive changes in chitin porosity appeared upon treatment with chitinase. This enzyme exhibited antifungal activity against Rhizoctonia solani, Bipolaris sp, Alternaria raphani, Alternaria brassicicola, revealing a potential application for the industry with potentially exploitable significance. Fungal chitin shows some special features, in particular with respect to chemical structure. Difference in chitinolytic ability must result from the subsite structure in the enzyme binding cleft. This implies that why the enzyme didn't have significant antifungal activity against other Fungi.

  11. Comparison of Dextran Perfusion and GSI-B4 Isolectin Staining in a Mouse Model of Oxygen-induced Retinopathy.

    Science.gov (United States)

    Huang, Shaofen; Liang, Jiajian; Yam, Gary Hin-Fai; Lu, Zhihao; Pang, Chi Pui; Chen, Haoyu

    2015-06-01

    Oxygen-induced retinopathy (OIR) is a robust and widely used animal model for the study of retinal neovascularization (NV). Dextran perfusion and Griffonia simplicifolia isolectin B4 (GSI-B4) staining are two common methods for examining the occurrence and extent of OIR. This study provides a quantitative comparison of the two for OIR detection. At postnatal day 7 (PN7), fifteen C57BL/6J mice were exposed to a 75% hyperoxic condition for 5 days and then returned to room air conditions. At PN17, the mice received intravitreal injection of GSI-B4 Alexa Fluor 568 conjugate. After 10 hours, they were infused with FITC-dextran conjugate via the left ventricle. Retinal flat mounts were photographed by confocal microscopy. Areas with fluorescent signals and the total retinal areas were quantified by Image J software. Both GSI-B4 and dextran detected the peripheral neovascular area. The mean hyper fluorescence area was 0.33 ± 0.14% of whole retinal area determined by GSI-B4 staining and 0.25 ± 0.28% determined by dextran perfusion. The difference between the two measures was 0.08% (95% CI:-0.59%, 0.43%). The Pearson correlation coefficient between the two methods was 0.386,P =0.035. The mean coincidence rates were 14.3 ± 13.4% and 24.9 ± 18.5% for GSI-B4 and dextran staining, respectively. Both methods can complement each other in demonstrating and quantitatively evaluating retinal NV. A poor agreement was found between the two methods; GSI-B4 isolectin was more effective than FITC-dextran perfusion in evaluating the extent of retinal NV in a mouse model of OIR.

  12. Resonant soft x-ray reflectivity of Me/B4C multilayers near the boron K edge

    Energy Technology Data Exchange (ETDEWEB)

    Ksenzov, Dmitriy; Schlemper, Christoph; Pietsch, Ullrich

    2010-09-01

    Energy dependence of the optical constants of boron carbide in the short period Ru/B4C and Mo/B4C multilayers (MLs) are evaluated from complete reflectivity scans across the boron K edge using the energy-resolved photon-in-photon-out method. Differences between the refractive indices of the B4Cmaterial inside and close to the surface are obtained from the peak profile of the first order ML Bragg peak and the reflection profile near the critical angle of total external reflection close to the surface. Where a Mo/B4C ML with narrow barrier layers appears as a homogeneous ML at all energies, a Ru/B4C ML exhibits another chemical nature of boron at the surface compared to the bulk. From evaluation of the critical angle of total external reflection in the energy range between 184 and 186 eV, we found an enriched concentration of metallic boron inside the Ru-rich layer at the surface, which is not visible in other energy ranges.

  13. Spin re-orientation in heavy fermion system α - YbAl1 - x FexB4

    Science.gov (United States)

    Wu, Shan; Broholm, C.; Kuga, K.; Suzuki, Shintaro; Nakatsuji, S.; Mourigal, M.; Stone, M.; Tian, Wei; Qiu, Y.; Rodriguez-Rivera, Jose

    Non centro-symmetric α - YbAlB4 has a heavy Fermi liquid ground state and shares many characteristics with centro-symmetric β - YbAlB4 . Both isomorphs display intermediate valence, associated with a fluctuation scale of T0 = 200 K and a Kondo lattice scale of T* = 8 K. Unlike β - YbAlB4 , α - YbAlB4 is at the boundary of a transition from a Fermi liquid metallic state to an antiferromagnetic (AFM) insulating state, driven by Fe substitution of Al. Magnetization and specific heat measurements reveal two different antiferromagnetic phases with TN = 9 K and TN = 2 K for Fe concentration above and below x =0.07. We report single crystal neutron scattering experiments on Fe doped YbAlB4 with x =0.035 and x =0.125. While the ordering wave vector is identical, k -> = (1 , 0 , 0) , the spin orientation switches from c to a with increasing Fe concentration. This suggests different anisotropic hybridization between 4f and conduction electrons that we confirmed by determining the crystal field levels. Supported by DOE, BES through DE-FG02-08ER46544.

  14. Ablating ErbB4 in PV neurons attenuates synaptic and cognitive deficits in an animal model of Alzheimer's disease.

    Science.gov (United States)

    Zhang, Heng; Zhang, Ling; Zhou, Dongming; He, Xiao; Wang, Dongpi; Pan, Hongyu; Zhang, Xiaoqin; Mei, Yufei; Qian, Qi; Zheng, Tingting; Jones, Frank E; Sun, Binggui

    2017-10-01

    Accumulation of amyloid β (Aβ) induces neuronal, synaptic, and cognitive deficits in patients and animal models of Alzheimer's disease (AD). The underlying mechanisms, however, remain to be fully elucidated. In the present study, we found that Aβ interacted with ErbB4, a member of the receptor tyrosine kinase family and mainly expressed in GABAergic interneurons. Deleting ErbB4 in parvalbumin-expressing neurons (PV neurons) significantly attenuated oligomeric Aβ-induced suppression of long term potentiation (LTP). Furthermore, specific ablation of ErbB4 in PV neurons via Cre/loxP system greatly improved spatial memory and synaptic plasticity in the hippocampus of hAPP-J20 mice. The deposition of Aβ detected by 3D6 and Thioflavin S staining and the proteolytic processing of hAPP analyzed by western blotting were not affected in the hippocampus of hAPP-J20 mice by deleting ErbB4 in PV neurons. Our data suggested that ErbB4 in PV neurons mediated Aβ-induced synaptic and cognitive dysfunctions without affecting Aβ levels. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. Hypothyroid Patients Encoding Combined MCT10 and DIO2 Gene Polymorphisms May Prefer L-T3 + L-T4 Combination Treatment - Data Using a Blind, Randomized, Clinical Study

    DEFF Research Database (Denmark)

    Carlé, Allan; Faber, Jens; Steffensen, Rudi

    2017-01-01

    on the cellular membrane transport-facilitating monocarboxylate transporter (MCT10) gene (rs17606253), and asked in which of the 2 treatment periods patients felt better (i.e., which treatment was preferred). RESULTS: 27 out of 45 patients (60%) preferred the combination therapy. Two polymorphisms (rs225014 (DIO2......, Thr92Ala) and rs17606253 (MCT10)) were combined yielding 3 groups: none vs. 1 of 2 vs. both SNPs present, and 42 vs. 63 vs. 100% of our patients in the 3 groups preferred the combined treatment (Jongheere-Terpstra trend test, p = 0.009). CONCLUSION: The present study indicates that the combination...... of polymorphisms in DIO2 (rs225014) and MCT10 (rs17606253) enhances hypothyroid patients' preference for L-T4 + L-T3 replacement therapy. In the future, combination therapy may be restricted or may be even recommended to individuals harbouring certain polymorphisms....

  16. Polarized neutron scattering study of the multiple order parameter system NdB4

    Science.gov (United States)

    Metoki, N.; Yamauchi, H.; Matsuda, M.; Fernandez-Baca, J. A.; Watanuki, R.; Hagihala, M.

    2018-05-01

    Neutron polarization analysis has been carried out in order to clarify the magnetic structures of multiple order parameter f -electron system NdB4. We confirmed the noncollinear "all-in all-out" structure (Γ4) of the in-plane moment, which is in good agreement with our previous neutron powder diffraction study. We found that the magnetic moment along the c -axis mc showed diagonally antiferromagnetic structure (Γ10), inconsistent with previously reported "vortex" structure (Γ2). The microscopic mixture of these two structures with q⃗0=(0 ,0 ,0 ) appears in phase II and remains stable in phases III and IV, where an incommensurate modulation coexists. The unusual magnetic ordering is phenomenologically understood via Landau theory with the primary order parameter Γ4 coupled with higher-order secondary order parameter Γ10. The magnetic moments were estimated to be 1.8 ±0.2 and 0.2 ±0.05 μB at T =7.5 K for Γ4 and Γ10, respectively. We also found a long-period incommensurate modulation of the q⃗1=(0 ,0 ,1 /2 ) antiferromagnetic structure of mc with the propagation q⃗s 1=(0.14 ,0.14 ,0.1 ) and q⃗s 2=(0.2 ,0 ,0.1 ) in phase III and IV, respectively. The amplitude of sinusoidal modulation was about mc=1.0 ±0.2 μB at T =1.5 K. The local (0 ,0 ,1 /2 ) structure consists of in-plane ferromagnetic and out-of-plane antiferromagnetic coupling of mc, opposite to the coexisting Γ10. The mc of Γ10 is significantly enhanced up to 0.6 μB at T =1.5 K, which is accompanied by the incommensurate modulations. The Landau phenomenological approach indicates that the higher-order magnetic and/or multipole interactions based on the pseudoquartet f -electron state play important roles.

  17. Effects of thyroid hormone analogue and a leukotrienes pathway-blocker on renal ischemia/reperfusion injury in mice

    Directory of Open Access Journals (Sweden)

    Hadi Najah R

    2011-12-01

    Full Text Available Abstract Background Acute renal failure (ARF is an important clinical problem with a high mortality and morbidity. One of the primary causes of ARF is ischemia/reperfusion (I/R. Inflammatory process and oxidative stress are thought to be the major mechanisms causing I/R. MK-886 is a potent inhibitor of leukotrienes biosynthesis which may have anti-inflammatory and antioxidant effects through inhibition of polymorphonuclear leukocytes (PMNs infiltration into renal tissues. 3, 5-diiodothyropropionic acid (DITPA have evidences of improving effects on I/R in heart through modulation of cellular signaling in response to ischemic stress. The objective of present study was to assess the effects of MK-886 and DITPA on renal I/R injury. Methods A total of 24 Adult males of Swiss albino mice were randomized to four groups: I/R group (n = 6, mice underwent 30 minute bilateral renal ischemia and 48 hr reperfusion. Sham group (n = 6, mice underwent same anesthetic and surgical procedures except for ischemia induction. MK-886-treated group: (n = 6, I/R + MK-886 (6 mg/kg by intraperitoneal injection. DITPA-treated group: (n = 6, I/R + DITPA (3.75 mg/kg by intraperitoneal injection. After the end of reperfusion phase mice were sacrificed, blood samples were collected directly from the heart for determination of serum TNF-a, IL-6, urea and Creatinine. Both kidney were excised, the right one homogenized for oxidative stress parameters (MDA and GSH measurements and the left kidney fixed in formalin for histological examination. Results Serum TNF-α, IL-6, urea and Creatinine, kidney MDA levels and scores of histopathological changes were significantly (P 0.05 changes in levels of all study parameters as compared with that of I/R group. Conclusion The results of the present study show that MK-886 significantly ameliorated kidney damage that resulted from I/R. For DITPA, as its administration might not be successful, administration using a different protocol may

  18. Peculiar features of thermal emission of GdB4 and GdB6 single crystals

    International Nuclear Information System (INIS)

    Ostrovskij, E.K.; Taran, A.A.; Kovalev, A.V.; Tkachenko, V.F.; Dudnik, E.M.; Matvienko, A.A.

    1990-01-01

    Thermoemission parameters of single crystals (410) GdB 4 and (110) GdB 6 are studied. Work function is calculated by total current. It is stated that work function of GdB 6 within temperature range of 1500-1880 K after 80 h of annealing varies from 2.95 to 3.10 eV practically with the same temperature coefficient as GdB 4 , i.e. 4.1x10 -4 eV/K. It is shown that single crystal gadolinium hexaboride during the high-temperature annealing in the surface region (∼70 mm) is transformed into gadolinium tetraboride. Influence of free air has been first studied on the GdB 4 emissivity which is determined to increase to p=1.3x10 -2 Pa within the range of T=1640-1840 K

  19. Wetting and interface interactions in the B4C/Al-Me (Me=Cu, Sn) systems

    International Nuclear Information System (INIS)

    Aizenshtein, M.; Froumin, N.; Dariel, M.P.; Frage, N.

    2008-01-01

    The wettability of B 4 C in contact with non-carbide and non-boride forming liquid metals (such as Cu or Sn) has been the subject of several studies. These metals do not wet boron carbide unless a reactive element is added to the melt. The present study is concerned with the addition of Al which completes the series of reactive elements added to the non-wetting metals. While Si represents the elements that form stable carbides and Ti represents the elements that form stable borides, Al belongs to the group of elements that form ternary borocarbides. The wetting experiments in the B 4 C/(Me-Al, Me=Cu, Sn) systems have shown that a ternary product, namely Al 8 B 4 C 7 was formed at the interface and that wetting is governed by the thermodynamic properties of the binary liquid system

  20. Spectral characterisation of aperiodic normal-incidence Sb/B4C multilayer mirrors for the λ < 124 Å range

    Science.gov (United States)

    Vishnyakov, E. A.; Kopylets, I. A.; Kondratenko, V. V.; Kolesnikov, A. O.; Pirozhkov, A. S.; Ragozin, E. N.; Shatokhin, A. N.

    2018-03-01

    Three broadband aperiodic Sb/B4C multilayer mirrors were synthesised for the purposes of soft X-ray optics and spectroscopy in the wavelength range beyond the L-edge of Si (λ plasma radiation source and an electronic detector with a 2D spatial resolution (a CCD matrix with 13 × 13 μm sized pixels). The experimental spectra are compared with theoretical calculations. The effect of lower antimony and B4C layer densities on the reflection spectra is discussed.

  1. Development of Mg B4 O7:Dy thermoluminescent solid dosemeter for using on the thermal neutron dosimetry

    International Nuclear Information System (INIS)

    Potiens Junior, A.J.; Campos, L.L.; Todo, A.S.

    1992-01-01

    The magnesium tetraborate doped with dysprosium (Mg B 4 O 7 :O y ) thermoluminescent phosphor is developed, containing boron, which boron 10 isotope has high cross section for thermal neutrons by 10 B (n,α) 7 Li reaction. The nitric acid concentration, the number of washing for removing the excess of boric acid, the powder granulation of Mg B 4 O 7 :O y , the percentage of teflon used as binder and the reproducibility of thermoluminescent answer are also presented. (C.G.C.)

  2. Thermal transformation of synthetic borax, Na2[B4O5(OH)4]x8H2O

    International Nuclear Information System (INIS)

    Abdullaev, G.K.

    1981-01-01

    Using the methods of high temperature roentgenography and derivatography thermal transformation of synthetic borax is studied. It is established that borax dehydration proceeds in four stages (50-80, 80-100, 100-150 and 150-500 deg C) with the formation of three intermediate crystalline hydrate forms (one stable and two unstable) and one final stable crystalline phase. The stable crystalline phases correspond to synthetic tincalconite Na 2 [B 4 O 5 (OH) 4 ]x3H 2 O and sodium tetraborate Na 2 B 4 O 7 . Thermal transformation of borax into tincalconite and sodium tetraborate is explained on the basis of their crystal structures [ru

  3. Homotopy perturbation method with Laplace Transform (LT-HPM) for solving Lane-Emden type differential equations (LETDEs).

    Science.gov (United States)

    Tripathi, Rajnee; Mishra, Hradyesh Kumar

    2016-01-01

    In this communication, we describe the Homotopy Perturbation Method with Laplace Transform (LT-HPM), which is used to solve the Lane-Emden type differential equations. It's very difficult to solve numerically the Lane-Emden types of the differential equation. Here we implemented this method for two linear homogeneous, two linear nonhomogeneous, and four nonlinear homogeneous Lane-Emden type differential equations and use their appropriate comparisons with exact solutions. In the current study, some examples are better than other existing methods with their nearer results in the form of power series. The Laplace transform used to accelerate the convergence of power series and the results are shown in the tables and graphs which have good agreement with the other existing method in the literature. The results show that LT-HPM is very effective and easy to implement.

  4. Peculiar features of metallurgical processes at plasma-arc spraying of coatings, made of steel wire with powder fillers B4C and B4C+ZrO2

    Directory of Open Access Journals (Sweden)

    Георгій Михайлович Григоренко

    2016-11-01

    Full Text Available The interaction of metallurgical processes occurring in plasma-arc spraying between the steel shell and the carbide fillers of B4C and B4C cored wires with the addition of nanocrystalline ZrO2 powder has been analyzed. Iron-boron compounds alloyed with carbon are formed in ingots as a result of ferritiс coating of wire interacrion with fillers while the ferritic matrix contains boride and carboboride eutectics. Average microhardness of the carboboride compounds and the matrix is high – 17,78; 16,40 and 8,69; 9,95 GPa for the ingots with с B4C and B4C+ZrO2 respectively. The best quality coatings with low porosity (~1%, lamellar structure consisting of ferrite matrix reinforced with dispersed Fe borides, were obtained at a higher heat input (plasmatron current 240-250 A. The average amount of oxides in the coatings makes 15%. 0,5% addition of nanopowder ZrO2 accelerates dispersed iron-boron compounds forming, promotes their uniform distribution in the structure and improves coating microhardness up to 7,0 GPa. Application of the differential thermal analysis method to simulate the interaction processes between the steel shell and the filler during the heating of wire in the shielding gas makes it possible to promote formation of new phases (borides and carboborides of iron and to predict the phase composition of the coatings

  5. Nido-Carborane building-block reagents. 2. Bulky-substituent (alkyl)2C2B4H6 derivatives and (C6H5)2C2B4H6: synthesis and properties

    International Nuclear Information System (INIS)

    Boyter, H.A. Jr.; Grimes, R.N.

    1988-01-01

    The preparation and chemistry of nido-2,3-R 2 C 2 C 2 B 4 H 6 carboranes in which R is n-butyl, isopentyl, n-hexyl, and phenyl was investigated in order to further assess the steric and electronic influence of the R groups on the properties of the nido-C 2 B 4 cage, especially with respect to metal complexation at the C 2 B 3 face and metal-promoted oxidative fusion. The three dialkyl derivatives were prepared from the corresponding dialkylacetylenes via reaction with B 5 H 9 and triethylamine, but the diphenyl compound could not be prepared in this manner and was obtained instead in a thermal reaction of B 5 H 9 with diphenylacetylene in the absence of amine. All four carboranes are readily bridge-deprotonated by NaH in THF, and the anions of the dialkyl species, on treatment with FeCl 2 and air oxidation, generate the respective R 4 C 4 B 8 H 8 carborane fusion products were R = n-C 4 H 9 , i-C 5 H 11 or n-C 6 H 13 . The diphenylcarborane anion Ph 2 C 2 B 4 H 5 - did not form detectable metal complexes with Fe 2+ , Co 2+ , or Ni 2+ , and no evidence of a Ph 4 C 4 B 8 H 8 fusion product has been found. Treatment of Ph 2 C 2 B 4 H 6 with Cr(CO) 6 did not lead to metal coordination of the phenyl rings, unlike (PhCH 2 ) 2 C 2 B 4 H 6 , which had previously been shown to form mono- and bis(tricarbonylchromium) complexes. However, the reaction of Ph 2 C 2 B 4 H 5 - , CoCl 2 , and (PhPCH 2 ) 2 did give 1,1-(Ph 2 PCH 2 ) 2 -1-Cl-1,2,3-Co(Ph 2 C 2 B 4 H 4 ), the only case in which metal complexation of the diphenylcarborane was observed. 14 references, 3 figures, 3 tables

  6. Conduction electron spin resonance in the α-Yb1−xFexAlB4 (0 ⩽ x ⩽ 0.50) and α-LuAlB4 compounds

    International Nuclear Information System (INIS)

    Holanda, L M; Lesseux, G G; Urbano, R R; Rettori, C; Pagliuso, P G; Magnavita, E T; Ribeiro, R A; Nakatsuji, S; Kuga, K; Fisk, Z; Oseroff, S B

    2015-01-01

    β-YbAlB 4 has become one of the most studied heavy fermion systems since its discovery due to its remarkable physical properties. This system is the first reported Yb-based heavy-fermion superconductor (HFS) for which the low-T superconducting state emerges from a non-fermi-liquid (NFL) normal state associated with quantum criticality Nakatsuji et al 2008 Nature 4 603. Additionally, it presents a striking and unprecedented electron spin resonance (ESR) signal which behaves as a conduction electron spin resonance (CESR) at high temperatures and acquires features of the Yb 3+ local moment ESR at low temperatures. The latter, also named Kondo quasiparticles spin resonance (KQSR), has been defined as a 4f-ce strongly coupled ESR mode that behaves as a local probe of the Kondo quasiparticles in a quantum critical regime, Holanda et al 2011 Phys. Rev. Lett. 107 026402. Interestingly, β-YbAlB 4 possesses a previously known structural variant, namely the α-YbAlB 4 , phase which is a paramagnetic Fermi liquid (FL) at low temperatures Macaluso et al 2007 Chem. Mater. 19 1918. However, it has been recently suggested that the α-YbAlB 4 phase may be tuned to NFL behavior and/or magnetic ordering as the compound is doped with Fe. Here we report ESR studies on the α-Yb 1−x Fe x AlB 4 (0 ⩽ x ⩽ 0.50) series as well as on the reference compound α-LuAlB 4 . For all measured samples, the observed ESR signal behaves as a CESR in the entire temperature range (10 K ≲ T ≲ 300 K) in clear contrast with what has been observed for β-YbAlB 4 . This striking result indicates that the proximity to a quantum critical point is crucial to the occurrence of a KQSR signal. (paper)

  7. Sigma Theta Tau, DAaL/Texas Nurse Association, 2017 South Texas Nurse Imagemaker, Lt Col Jacqueline Killian

    Science.gov (United States)

    2018-04-28

    ENDORSEMENT (59 MDW/SGVU Use Only) 43. REVIEWER SIGNATURE 32. DATE 38. DATE 44. DATE April 11 , 20 17 45. DATE RECEIVED 1 46. SENIOR AUTHOR NOTIFIED BY...EBP mentors to facilitate the growing number of EBP projects underway in our organization. 1 Lt Col Killian serves as research consultant to chief...for helping others. The first project is focused on enhancing resil ience in our military families--the " Mentors Offering Maternal Support (M-0-M

  8. Marker-Assisted Selection of Xa21 Conferring Resistance to Bacterial Leaf Blight in indica Rice Cultivar LT2

    Directory of Open Access Journals (Sweden)

    Hue Thi Nguyen

    2018-01-01

    Full Text Available Bacterial leaf blight of rice (BLB, caused by Xanthomonas oryzae pv. oryzae, is one of the most destructive diseases in Asian rice fields. A high-quality rice variety, LT2, was used as the recipient parent. IRBB21, which carries the Xa21 gene, was used as the donor parent. The resistance gene Xa21 was introduced into LT2 by marker-assisted backcrossing. Three Xoo races were used to inoculate the improved lines following the clipping method. Eleven BC3F3 lines carrying Xa21 were obtained based on molecular markers and agronomic performance. The 11 lines were then inoculated with the three Xoo races. All the 11 improved lines showed better resistance to BLB than the recipient parent LT2. Based on the level of resistance to BLB and their agronomic performance, five lines (BC3F3 5.1.5.1, BC3F3 5.1.5.12, BC3F3 8.5.6.44, BC3F3 9.5.4.1 and BC3F3 9.5.4.23 were selected as the most promising for commercial release. These improved lines could contribute to rice production in terms of food security.

  9. Marker-Assisted Selection of Xa21 Conferring Resistance to Bacterial Leaf Blight in indica Rice Cultivar LT2

    Institute of Scientific and Technical Information of China (English)

    Hue Thi NGUYEN; Trung Nguyen DINH; Nakano TOSHITSUGU; Liet Van VU; Quang Hong VU; Tan Van MAI; Thu Thi NGUYEN; Lam Duc VU; Tung Thanh NGUYEN; Long Viet NGUYEN; Hien Thu Thi VU; Hue Thi NONG

    2018-01-01

    Bacterial leaf blight of rice (BLB), caused by Xanthomonas oryzae pv. oryzae, is one of the most destructive diseases in Asian rice fields. A high-quality rice variety, LT2, was used as the recipient parent. IRBB21, which carries the Xa21 gene, was used as the donor parent. The resistance gene Xa21 was introduced into LT2 by marker-assisted backcrossing. Three Xoo races were used to inoculate the improved lines following the clipping method. Eleven BC3F3lines carrying Xa21 were obtained based on molecular markers and agronomic performance. The 11 lines were then inoculated with the three Xoo races. All the 11 improved lines showed better resistance to BLB than the recipient parent LT2. Based on the level of resistance to BLB and their agronomic performance, five lines (BC3F35.1.5.1, BC3F35.1.5.12, BC3F38.5.6.44, BC3F3 9.5.4.1 and BC3F39.5.4.23) were selected as the most promising for commercial release. These improved lines could contribute to rice production in terms of food security.

  10. Study on characterization of interaction layer between U-10wt%Mo alloy and LT24Al

    International Nuclear Information System (INIS)

    Chen Jiangang; Yin Changgeng; Sun Changlong; Pang Xiaoxuan; Liu Yunming

    2009-01-01

    The characterization of interaction layer(IL) between U-10wt%Mo alloy and LT24 Al was studied in detail in this paper. Sandwich structured U-Mo/LT24 Al diffusion couples were hot pressed at different temperature and pressure for different time. Then they were analyzed by Optical Microscope (OM) and Scanning Electron Microscope (SEM) to observe the width of the IL. The distribution of the diffusion elements and the phases in the IL were determined by Energy Dispersive Spectroscopy (EDS) and X Ray Diffraction (XRD). Analysis results are as follows: the diffusion manner was reaction diffusion, and diffusion direction mainly was that Al atoms diffused to U-Mo alloy; diffusion mechanism was vacancy diffusion and growth kinetics showed reaction was controlled by the diffusion speed; the IL containing single phase was constituted mainly by (U, Mo) Al 3 ; the IL containing two phases or more was constituted mainly by (U, Mo) Al 3 and (U, Mo) Al 4 and Al 20 Mo 2 U; and Si impurity in the LT24 Al was easy to enrich in the IL which showed Si added to Al could play positive role on improve compatibility between U-Mo and Al. (authors)

  11. Nikkaji Dictionary: フモニシンB4 [MeCab user dictionary for science technology term[Archive

    Lifescience Database Archive (English)

    Full Text Available MeCab user dictionary for science technology term フモニシンB4 名詞 一般 * * * * フモニシン...B4 ... Nikkaji J541.900J 200906063560729330 C CA06 UNKNOWN_2 フモニシン B 4

  12. 76 FR 20506 - Technical Amendment to Rule 19b-4: Filings With Respect to Proposed Rule Changes by Self...

    Science.gov (United States)

    2011-04-13

    ... under the Small Business Regulatory Enforcement Fairness Act. See 5 U.S.C. 601(2) (for purposes of RFA... anticipate that any competitive advantages or disadvantages would be created. List of Subjects in 17 CFR Part... that references to ``business day'' in Section 19(b) of the Exchange Act and Rule 19b-4 thereunder...

  13. 26 CFR 1.367(b)-4 - Acquisition of foreign corporate stock or assets by a foreign corporation in certain...

    Science.gov (United States)

    2010-04-01

    ...) and any regulations thereunder. If any of the assets transferred are intangible assets, see section... 26 Internal Revenue 4 2010-04-01 2010-04-01 false Acquisition of foreign corporate stock or assets...) INCOME TAXES Effects on Corporation § 1.367(b)-4 Acquisition of foreign corporate stock or assets by a...

  14. Structure and hindered vibration of Bi2+ in the red-orange phosphor SrB4O7:Bi

    NARCIS (Netherlands)

    De Jong, Mathijs; Meijerink, A; Barandiarán, Zoila; Seijo, Luis

    2014-01-01

    The emission band profile of bismuth-doped SrB4O7 is measured with high resolution, and distinct vibronic features are observed at 4.2 K. The energy intervals show an irregular distribution. It is interpreted in the light of ab initio calculations as due to two off-center totally symmetric normal

  15. Analysis of the glow curve of SrB 4O 7:Dy compounds employing the GOT model

    Science.gov (United States)

    Ortega, F.; Molina, P.; Santiago, M.; Spano, F.; Lester, M.; Caselli, E.

    2006-02-01

    The glow curve of SrB 4O 7:Dy phosphors has been analysed with the general one trap model (GOT). To solve the differential equation describing the GOT model a novel algorithm has been employed, which reduces significantly the deconvolution time with respect to the time required by usual integration algorithms, such as the Runge-Kutta method.

  16. Analysis of the glow curve of SrB4O7:Dy compounds employing the GOT model

    International Nuclear Information System (INIS)

    Ortega, F.; Molina, P.; Santiago, M.; Spano, F.; Lester, M.; Caselli, E.

    2006-01-01

    The glow curve of SrB 4 O 7 :Dy phosphors has been analysed with the general one trap model (GOT). To solve the differential equation describing the GOT model a novel algorithm has been employed, which reduces significantly the deconvolution time with respect to the time required by usual integration algorithms, such as the Runge-Kutta method

  17. Purification through Emotions: The Role of Shame in Plato's "Sophist" 230B4-E5

    Science.gov (United States)

    Candiotto, Laura

    2018-01-01

    This article proposes an analysis of Plato's "Sophist" (230b4--e5) that underlines the bond between the logical and the emotional components of the Socratic "elenchus", with the aim of depicting the social valence of this philosophical practice. The use of emotions characterizing the 'elenctic' method described by Plato is…

  18. 29 CFR 2550.408b-4 - Statutory exemption for investments in deposits of banks or similar financial institutions.

    Science.gov (United States)

    2010-07-01

    ....408b-4 Statutory exemption for investments in deposits of banks or similar financial institutions. (a... financial institution may make investments in deposits which bear a reasonable rate of interest in itself... 29 Labor 9 2010-07-01 2010-07-01 false Statutory exemption for investments in deposits of banks or...

  19. Development of a high-performance composite cathode for LT-SOFC

    Science.gov (United States)

    Lee, Byung Wook

    Solid Oxide Fuel Cell (SOFC) has drawn considerable attention for decades due to its high efficiency and low pollution, which is made possible since chemical energy is directly converted to electrical energy through the system without combustion. However, successful commercialization of SOFC has been delayed due to its high production cost mainly related with using high cost of interconnecting materials and the other structural components required for high temperature operation. This is the reason that intermediate (IT) or low temperature (LT)-SOFC operating at 600~800°C or 650°C and below, respectively, is of particular significance because it allows the wider selection of cheaper materials such as stainless steel for interconnects and the other structural components. Also, extended lifetime and system reliability are expected due to less thermal stress through the system with reduced temperature. More rapid start-up/shut-down procedure is another advantage of lowering the operating temperatures. As a result, commercialization of SOFC will be more viable. However, there exists performance drop with reduced operating temperature due to increased polarization resistances from the electrode electrochemical reactions and decreased electrolyte conductivity. Since ohmic polarization of the electrolyte can be significantly reduced with state-of-the art thin film technology and cathode polarization has more drastic effect on total SOFC electrochemical performance than anode polarization as temperature decreases, development of the cathode with high performance operating at IT or LT range is thus essential. On the other hand, chemical stability of the cathode and its chemical compatibility with the electrolyte should also be considered for cathode development since instability and incompatibility of the cathode will also cause substantial performance loss. Based on requirements of the cathode mentioned above, in this study, several chemico-physical approaches were

  20. Turist Motivasyonunda Mahalli Kültür ve Etkisi ve Apart Ziyaretlerinde Turist Memnuniyeti

    Directory of Open Access Journals (Sweden)

    Nguyen Quang VINH

    2013-09-01

    Full Text Available Bu çalışma, apart turizm hizmet sektöründe stratejik pazarlama kararının tesis edilmesi anlayışını sağlamak için turizm planlamacılarına ve turizmcilere yardım etmeyi amaçlamaktadır. Ampirik analiz için Duonglam Eski Köyü’nün apart hizmetinden faydalanmış 150 uluslararası ziyaretçinin oluşturduğu datalar kullanılmıştır. Turist motivasyonu ve nihai varış noktası sadakatindeki memnuniyet arasındaki hipotezleri test etmek amacıyla regresyon yöntemi benimsenmiştir. Bu çalışma Duonglam köyündeki iklim şartları, nihai varış noktasına ulaşım kolaylığı, konaklama kalitesi, doğal güzellikler ve hijyen şartlarının turist memnuniyeti üzerinde önemli etkileri olduğu sonucunu çıkarmıştır. Diğer taraftan da bu sonuçlar Duonglam Eski Köyü’nün kültürel aktiviteleri ve turizm hizmet sektörü hakkında olumsuz bir kanıyı temsil etmektedir. Ayrıca çalışmada, araştırmanın sınırı ve turizm sektörü çalışanları için elde edilen bulguların sonuçları tartışılmıştır.

  1. The Collaborative Lithium Trials (CoLT: specific aims, methods, and implementation

    Directory of Open Access Journals (Sweden)

    Hooper Stephen R

    2008-08-01

    Full Text Available Abstract Background Lithium is a benchmark treatment for bipolar illness in adults. However, there has been relatively little methodologically stringent research regarding the use of lithium in youth suffering from bipolarity. Methods Under the auspices of the Best Pharmaceuticals for Children Act (BPCA, a Written Request (WR pertaining to the study of lithium in pediatric mania was issued by the United States Food and Drug Administration (FDA to the National Institute of Child Health and Human Development (NICHD in 2004. Accordingly, the NICHD issued a Request for Proposals (RFP soliciting submissions to pursue this research. Subsequently, the NICHD awarded a contract to a group of investigators in order to conduct these studies. Results The Collaborative Lithium Trials (CoLT investigators, the BPCA-Coordinating Center, and the NICHD developed protocols to provide data that will: (1 establish evidence-based dosing strategies for lithium; (2 characterize the pharmacokinetics and biodisposition of lithium; (3 examine the acute efficacy of lithium in pediatric bipolarity; (4 investigate the long-term effectiveness of lithium treatment; and (5 characterize the short- and long-term safety of lithium. By undertaking two multi-phase trials rather than multiple single-phase studies (as was described in the WR, the feasibility of the research to be undertaken was enhanced while ensuring all the data outlined in the WR would be obtained. The first study consists of: (1 an 8-week open-label, randomized, escalating dose Pharmacokinetic Phase; (2 a 16-week Long-Term Effectiveness Phase; (3 a 28-week double-blind Discontinuation Phase; and (4 an 8-week open-label Restabilization Phase. The second study consists of: (1 an 8-week, double-blind, parallel-group, placebo-controlled Efficacy Phase; (2 an open-label Long-Term Effectiveness lasting either 16 or 24 weeks (depending upon blinded treatment assignment during the Efficacy Phase; (3 a 28-week double

  2. Thermoluminescence properties of Li2B4O7:Cu, B phosphor synthesized using solution combustion technique

    International Nuclear Information System (INIS)

    Ozdemir, A.; Altunal, V.; Kurt, K.; Depci, T.; Yu, Y.; Lawrence, Y.; Nur, N.; Guckan, V.; Yegingil, Z.

    2017-01-01

    To determine the effects of various concentrations of the activators copper (Cu) and boron (B) on the thermoluminescence (TL) properties of lithium tetraborate, the phosphor was first synthesized and doped with five different concentrations of copper (0.1–0.005 wt%) using solution combustion method. 0.01 wt% Cu was the concentration which showed the most significant increase in the sensitivity of the phosphor. The second sort of Li 2 B 4 O 7 :Cu material was prepared by adding B (0.001–0.03 wt%) to it. The newly developed copper-boron activated lithium tetraborate (Li 2 B 4 O 7 :Cu, B) material with 0.01 wt% Cu and 0.001 wt% B impurity concentrations was shown to have promise as a TL phosphor. The material formation was examined using powder x-Ray Diffraction (XRD) analysis and Scanning Electron Microscope (SEM) imaging. Fourier Transform Infrared (FT-IR) spectrum of the synthesized polycrystalline powder sample was also recorded. The TL glow curves were analyzed to determine various dosimetric characteristics of the synthesized luminophosphors. The dose response increased in a “linear” way with the beta-ray exposure between 0.1–20 Gy, a dose range being interested in medical dosimetry. The response with changing photon and electron energy was studied. The rate of decay of the TL signal was investigated both for dark storage and under direct sunlight. Li 2 B 4 O 7 :Cu, B showed no individual variation of response in 9 recycling measurements. The fluorescence spectrum was determined. The kinetic parameters were estimated by different methods and the results discussed. The studied properties of synthesized Li 2 B 4 O 7 :Cu, B were found all favorable for dosimetric purposes. - Highlights: • Li 2 B 4 O 7 :Cu, B synthesis using solution combustion method with various concentrations. • Structure analysis of Li 2 B 4 O 7 :Cu, B using XRD, SEM and FTIR methods. • Investigation of thermoluminescent properties of Li 2 B 4 O 7 :Cu, B. • Relatively good

  3. Human LT-alpha-mediated resistance to autoimmune diabetes is induced in NOD, but not NOD-scid, mice and abrogated by IL-12.

    Science.gov (United States)

    Miyaguchi, S; Satoh, J; Takahashi, K; Sakata, Y; Nakazawa, T; Miyazaki, J; Toyota, T

    2001-01-01

    Systemic administration of human lymphotoxin-alpha (hLT-alpha) made NOD mice resistant not only to spontaneous autoimmune type 1 diabetes mellitus but also to cyclophosphamide (CY)-induced diabetes and diabetes transfer by diabetic NOD spleen cells (triple resistance). In this study we analyzed the mechanisms of hLT-alpha-induced resistance, focusing on (1) hLT-alpha-induced resistance in the pancreatic beta cell, (2) CY-resistant suppressor cells, (3) suppression of induction or function of effector cells for beta cell destruction, or (4) others. To examine the first possibility in vitro, a NOD-derived beta cell line (MIN6N) was pretreated with hLT-alpha and then mixed with diabetic NOD spleen cells and MIN6N cell viability was measured. Treatment with hLT-alpha did not protect MIN6N cells but rather enhanced cytotoxicity. Next NOD-scid mice were pretreated with hLT-alpha and then transferred with diabetic NOD spleen. All the recipients developed diabetes. These results excluded the first possibility. The second possibility was also excluded by a cotransfer experiment, in which diabetic NOD spleen cells were cotransferred to NOD-scid mice with nontreated or hLT-alpha-treated nondiabetic NOD spleens. There was no significant difference in diabetes incidence between the two groups. To observe the third possibility, spleen cells of hLT-alpha-treated triple-resistant NOD mice were transferred to NOD-scid mice. Diabetes developed in the recipients, although the onset of diabetes was slightly delayed. Finally, hLT-alpha-treated triple-resistant NOD mice developed diabetes 1 week after daily IL-12 treatment. In summary, hLT-alpha administration made NOD mice resistant to effector cells for beta cell destruction. This resistance was induced in NOD, but not in NOD-scid, mice, indicating that lymphocytes were obligatory for the resistance. However, it was not mediated by transferable suppressor cells. Because effector cells were present in hLT-alpha-treated NOD spleen and

  4. [Treatment of ASS-Associated Polyposis (ASSAP) with a cysteinyl leukotriene receptor antagonist - a prospective drug study on its antiinflammatory effects].

    Science.gov (United States)

    Grundmann, T; Töpfner, M

    2001-10-01

    In a high rate of cases with recurrent polyposis an association with ASS-intolerance is detectable despite missing pulmonary symptoms. New examinations of a disturbed arachidonic acid metabolism lead to the development of new therapeutical options. Treatment with leukotriene-receptor antogonists (LTA) showed primarily good results in therapy of ASS-associated asthma. 18 patients with ASS-intolerance trias - diagnosed by oral provocation - were treated with the LTA Montelukast, after undergoing sinus surgery. Patients underwent a diagnostic pathway of provocation including four groups: recurrent chronic sinusitis, excessive polyposis, polyposis associated with asthma and anaphylactic symptoms after oral ASS-intake. Clinically we examined the following parameters periodically after sinus surgery: nasal and pulmonal symptoms by scoring levels, recurrency of polypoid hyperplasia by endoscopic follow-ups and serum ECP-levels. To evaluate antiinflammatory tissue effects of LTA EG1/EG2 labelled cells and cytokine levels of Interleukin 5 in mucosa samples of the lower turbinate were analysed under LTA-therapy. Under therapy with LTA we saw a beneficial effect on nasal and pulmonary symptoms and a significant reduction of recurrent polyposis in endoscopic examinations in relation to the untreated group. Results were proven by a permanent reduction of serum ECP-level. A reduction of the rate of EG2-positive cells according to decreased Interleukin 5 levels in the nasal mucosa unter LTA-treatment assumed antiinflammatory effects on ASS-associated polyposis. We could demonstrate antiinflammatory effects of Leukotriene-Receptor-Antagonists primarily during postoperative treatment of patients with ASS-associated nasal polyps.

  5. Non-genomic action of beclomethasone dipropionate on bronchoconstriction caused by leukotriene C4 in precision cut lung slices in the horse

    Directory of Open Access Journals (Sweden)

    Fugazzola Maria

    2012-09-01

    Full Text Available Abstract Background Glucocorticoids have been proven to be effective in the therapy of recurrent airway obstruction (RAO in horses via systemic as well as local (inhalative administration. Elective analysis of the effects of this drug on bronchoconstriction in viable lung tissue offers an insight into the mechanism of action of the inflammatory cascade occurring during RAO which is still unclear. The mechanism of action of steroids in treatment of RAO is thought to be induced through classical genomic pathways. We aimed at electively studying the effects of the glucocorticoid beclomethasone dipropionate on equine precision-cut lung slices (PCLS. PCLS were used to analyze ex-vivo effects of beclomethasone on inhibiting bronchoconstriction in the horse. The inhibiting effect was measured through instillation of a known mediator of inflammation and bronchoconstriction, leukotriene C4. For this, the accessory lobes of 13 horses subjected to euthanasia for reasons unrelated to the respiratory apparatus were used to obtain viable lung slices. Results After 30 minutes of PCLS incubation, beclomethasone showed to significantly inhibit the contraction of the bronchioles after instillation with leukotriene C4. The EC50 values of the two contraction curves (LTC4 with and without BDP differed significantly from each other (p = 0.002. The possibility of a non-genomic rapid mechanism of action seems likely since transcriptional activities require a longer lag period. Conclusions In human neuroendocrinology, high levels of glucocorticoids have been proven to function via a non-genomic mechanism of membrane receptors. The concentration of beclomethasone used on the lung slices in our study can be considered as high. This allows speculation about similar rapid non-genomic mechanisms of high-dosage inhaled glucocorticoids in the lower airways of horses. However, further assessment on a molecular basis is needed to confirm this.

  6. Fabrication of steel matrix composites locally reinforced with different ratios of TiC/TiB2 particulates using SHS reactions of Ni-Ti-B4C and Ni-Ti-B4C-C systems during casting

    International Nuclear Information System (INIS)

    Yang Yafeng; Wang Huiyuan; Liang Yunhong; Zhao Ruyi; Jiang Qichuan

    2007-01-01

    Steel matrix composites locally reinforced with different molar ratios of in situ TiC/TiB 2 particulates (2:1, 1:1 and 1:2, respectively) have been fabricated successfully utilizing the self-propagating high-temperature synthesis (SHS) reactions of Ni-Ti-B 4 C and Ni-Ti-B 4 C-C systems during casting. Differential thermal analysis (DTA) and X-ray diffraction (XRD) results reveal that the exothermic reactions of the Ni-Ti-B 4 C and Ni-Ti-B 4 C-C systems proceed in such a way that Ni initially reacts with B 4 C and Ti to form Ni 2 B and Ti 2 Ni compounds, respectively, with heat evolution at 1037 deg. C; Subsequently, the external heat and the evolved heat from these exothermic reactions promote the reactions forming TiC and TiB 2 at 1133 deg. C. In the composites reinforced with 1:2 molar ratio of TiC/TiB 2 , almost all TiB 2 grains have clubbed structures, while TiC grains exhibit near-spherical morphologies. Furthermore, TiB 2 grain sizes decrease, with the increase of TiC content. In particular, in the composites reinforced with 2:1 molar ratio of TiC/TiB 2 , it is difficult to find the clubbed TiB 2 grains. Macro-pores and blowholes are absent in the local reinforcing region of the composites reinforced with 1:1 and 1:2 molar ratios of TiC/TiB 2 , while a few macro-pores can be observed in the composite reinforced with 2:1 molar ratio of TiC/TiB 2 . Moreover, the densities of the composites reinforced with 1:1 and 1:2 molar ratios of TiC/TiB 2 are higher than that of the composite reinforced with 2:1 molar ratio of TiC/TiB 2 . The composite reinforced with 1:2 molar ratio of TiC/TiB 2 has the highest hardness and the best wear resistance

  7. Two-step infiltration of aluminum melts into Al-Ti-B4C-CuO powder mixture pellets

    Science.gov (United States)

    Zhang, Jingjing; Lee, Jung-Moo; Cho, Young-Hee; Kim, Su-Hyeon; Yu, Huashun

    2016-03-01

    Aluminum matrix composites with a high volume fraction of B4C and TiB2 were fabricated by a novel processing technique - a quick spontaneous infiltration process. The process combines a pressureless infiltration with the combustion reaction of Al-Ti-B4C-CuO in molten aluminum. The process is realized in a simple and economical way in which the whole process is performed in air in a few minutes. To verify the rapidity of the process, the infiltration kinetics was calculated based on the Washburn equation in which melt flows into a porous skeleton. However, there was a noticeable deviation from the calculated results with the experimental results. Considering the cross-sections of the samples at different processing times, a new infiltration model (two step infiltration) consisting of macro-infiltration and micro-infiltration is suggested. The calculated kinetics results in light of the proposed model agree well with the experimental results.

  8. Spontaneous structural distortion of the metallic Shastry-Sutherland system Dy B4 by quadrupole-spin-lattice coupling

    Science.gov (United States)

    Sim, Hasung; Lee, Seongsu; Hong, Kun-Pyo; Jeong, Jaehong; Zhang, J. R.; Kamiyama, T.; Adroja, D. T.; Murray, C. A.; Thompson, S. P.; Iga, F.; Ji, S.; Khomskii, D.; Park, Je-Geun

    2016-11-01

    Dy B4 has a two-dimensional Shastry-Sutherland (Sh-S) lattice with strong Ising character of the Dy ions. Despite the intrinsic frustrations, it undergoes two successive transitions: a magnetic ordering at TN=20 K and a quadrupole ordering at TQ=12.5 K . From high-resolution neutron and synchrotron x-ray powder diffraction studies, we have obtained full structural information on this material in all phases and demonstrate that structural modifications occurring at quadrupolar transition lead to the lifting of frustrations inherent in the Sh-S model. Our paper thus provides a complete experimental picture of how the intrinsic frustration of the Sh-S lattice can be lifted by the coupling to quadrupole moments. We show that two other factors, i.e., strong spin-orbit coupling and long-range Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction in metallic Dy B4 , play an important role in this behavior.

  9. A Novel Orange-Red Emitting ZnB4O7:Eu3+ Phosphor with Urchin-Like Nanostructure

    Directory of Open Access Journals (Sweden)

    Hom Nath Luitel

    2015-01-01

    Full Text Available A novel phosphor, ZnB4O7:Eu3+, with urchin-like structure consisting of radially arranged high density nanorods was successfully synthesized by hydrothermal process at 150°C for 24 h. The nanorods were measured from 200 to 400 nm in diameter and several µm in length. The urchins were few µm to 40 µm in diameter. The ZnB4O7:Eu3+ phosphors were efficiently excited by ultraviolet (UV ~ 254 nm to visible light of ~ 220 to 450 nm and exhibited intense orange-red emission consisting of main peaks at 590, 615, and 695 nm due to the charge transfer in the host and f→f transitions (5D0 to 7F1,2,4 of the Eu3+ ions. Effect of the Eu3+ ions concentration on the photoluminescence (PL emission intensity was investigated and it was found that 5 at% Eu3+ is the optimum concentration. Meanwhile, the concentration quenching mechanism was discussed. The key parameters, such as temperature dependent PL and CIE values of ZnB4O7:Eu3+ phosphors, were studied. The ZnB4O7:Eu3+ phosphor exhibited good thermal stability and better absorption cross section compared to the commercial Y2O2S:Eu3+ phosphor. All these characteristics indicate that the phosphor will be a potential candidate for the UV based white LEDs.

  10. ERBB4 Mutations that Disrupt the Neuregulin-ErbB4 Pathway Cause Amyotrophic Lateral Sclerosis Type 19

    Science.gov (United States)

    Takahashi, Yuji; Fukuda, Yoko; Yoshimura, Jun; Toyoda, Atsushi; Kurppa, Kari; Moritoyo, Hiroyoko; Belzil, Veronique V.; Dion, Patrick A.; Higasa, Koichiro; Doi, Koichiro; Ishiura, Hiroyuki; Mitsui, Jun; Date, Hidetoshi; Ahsan, Budrul; Matsukawa, Takashi; Ichikawa, Yaeko; Moritoyo, Takashi; Ikoma, Mayumi; Hashimoto, Tsukasa; Kimura, Fumiharu; Murayama, Shigeo; Onodera, Osamu; Nishizawa, Masatoyo; Yoshida, Mari; Atsuta, Naoki; Sobue, Gen; Fifita, Jennifer A.; Williams, Kelly L.; Blair, Ian P.; Nicholson, Garth A.; Gonzalez-Perez, Paloma; Brown, Robert H.; Nomoto, Masahiro; Elenius, Klaus; Rouleau, Guy A.; Fujiyama, Asao; Morishita, Shinichi; Goto, Jun; Tsuji, Shoji

    2013-01-01

    Amyotrophic lateral sclerosis (ALS) is a devastating neurological disorder characterized by the degeneration of motor neurons and typically results in death within 3–5 years from onset. Familial ALS (FALS) comprises 5%–10% of ALS cases, and the identification of genes associated with FALS is indispensable to elucidating the molecular pathogenesis. We identified a Japanese family affected by late-onset, autosomal-dominant ALS in which mutations in genes known to be associated with FALS were excluded. A whole- genome sequencing and parametric linkage analysis under the assumption of an autosomal-dominant mode of inheritance with incomplete penetrance revealed the mutation c.2780G>A (p. Arg927Gln) in ERBB4. An extensive mutational analysis revealed the same mutation in a Canadian individual with familial ALS and a de novo mutation, c.3823C>T (p. Arg1275Trp), in a Japanese simplex case. These amino acid substitutions involve amino acids highly conserved among species, are predicted as probably damaging, and are located within a tyrosine kinase domain (p. Arg927Gln) or a C-terminal domain (p. Arg1275Trp), both of which mediate essential functions of ErbB4 as a receptor tyrosine kinase. Functional analysis revealed that these mutations led to a reduced autophosphorylation of ErbB4 upon neuregulin-1 (NRG-1) stimulation. Clinical presentations of the individuals with mutations were characterized by the involvement of both upper and lower motor neurons, a lack of obvious cognitive dysfunction, and relatively slow progression. This study indicates that disruption of the neuregulin-ErbB4 pathway is involved in the pathogenesis of ALS and potentially paves the way for the development of innovative therapeutic strategies such using NRGs or their agonists to upregulate ErbB4 functions. PMID:24119685

  11. Thermoluminescence properties of Li2B4O7:Cu, B phosphor synthesized using solution combustion technique

    Science.gov (United States)

    Ozdemir, A.; Altunal, V.; Kurt, K.; Depci, T.; Yu, Y.; Lawrence, Y.; Nur, N.; Guckan, V.; Yegingil, Z.

    2017-12-01

    To determine the effects of various concentrations of the activators copper (Cu) and boron (B) on the thermoluminescence (TL) properties of lithium tetraborate, the phosphor was first synthesized and doped with five different concentrations of copper (0.1-0.005 wt%) using solution combustion method. 0.01 wt% Cu was the concentration which showed the most significant increase in the sensitivity of the phosphor. The second sort of Li2B4O7:Cu material was prepared by adding B (0.001-0.03 wt%) to it. The newly developed copper-boron activated lithium tetraborate (Li2B4O7:Cu, B) material with 0.01 wt% Cu and 0.001 wt% B impurity concentrations was shown to have promise as a TL phosphor. The material formation was examined using powder x-Ray Diffraction (XRD) analysis and Scanning Electron Microscope (SEM) imaging. Fourier Transform Infrared (FT-IR) spectrum of the synthesized polycrystalline powder sample was also recorded. The TL glow curves were analyzed to determine various dosimetric characteristics of the synthesized luminophosphors. The dose response increased in a ;linear; way with the beta-ray exposure between 0.1-20 Gy, a dose range being interested in medical dosimetry. The response with changing photon and electron energy was studied. The rate of decay of the TL signal was investigated both for dark storage and under direct sunlight. Li2B4O7:Cu, B showed no individual variation of response in 9 recycling measurements. The fluorescence spectrum was determined. The kinetic parameters were estimated by different methods and the results discussed. The studied properties of synthesized Li2B4O7:Cu, B were found all favorable for dosimetric purposes.

  12. The use of the laryngeal tube disposable (LT-D) by paramedics during out-of-hospital resuscitation-an observational study concerning ERC guidelines 2005.

    Science.gov (United States)

    Wiese, C H R; Semmel, T; Müller, J U; Bahr, J; Ocker, H; Graf, B M

    2009-02-01

    In the current guidelines of the European Resuscitation Council (ERC), tracheal intubation, as an instrument for securing the airway during resuscitation, has become less important for persons not trained in this method. For those persons, different supraglottic airway devices are recommended by the ERC. The present investigation deals with the application of the laryngeal tube disposable (LT-D) during pre-hospital resuscitation by paramedics. During a period of 2 years (2006-2008), we registered all cardiac arrest situations in which the LT-D had been applied according to the ERC guidelines 2005. Therefore, we investigated one emergency medical system in Germany. During the defined period, 92 resuscitation attempts, recorded on standardised data sheets, were included. The LT-D was used in 46% of all cardiac arrest situations. Overall, the LT-D was successfully inserted in more than 90% of all cases on first attempt. In 95% of all cases, no problems concerning ventilation of the patient were described. As an alternative airway device recommended by the ERC in 2005, the LT-D may enable airway control rapidly and effectively. Additionally, by using the LT-D, a reduced "no-flow-time" and a better outcome may be possible.

  13. Sewage sludge amendment and inoculation with plant-parasitic nematodes do not facilitate the internalization of Salmonella Typhimurium LT2 in lettuce plants.

    Science.gov (United States)

    Fornefeld, Eva; Baklawa, Mohamed; Hallmann, Johannes; Schikora, Adam; Smalla, Kornelia

    2018-05-01

    Contamination of fruits and vegetables with Salmonella is a serious threat to human health. In order to prevent possible contaminations of fresh produce it is necessary to identify the contributing ecological factors. In this study we investigated whether the addition of sewage sludge or the presence of plant-parasitic nematodes foster the internalization of Salmonella enterica serovar Typhimurium LT2 into lettuce plants, posing a potential threat for human health. Greenhouse experiments were conducted to investigate whether the amendment of sewage sludge to soil or the presence of plant-parasitic nematodes Meloidogyne hapla or Pratylenchus crenatus promote the internalization of S. Typhimurium LT2 from soil into the edible part of lettuce plants. Unexpectedly, numbers of cultivable S. Typhimurium LT2 decreased faster in soil with sewage sludge than in control soil but not in root samples. Denaturing gradient gel electrophoresis analysis revealed shifts of the soil bacterial communities in response to sewage sludge amendment and time. Infection and proliferation of nematodes inside plant roots were observed but did not influence the number of cultivable S. Typhimurium LT2 in the root samples or in soil. S. Typhimurium LT2 was not detected in the leaf samples 21 and 49 days after inoculation. The results indicate that addition of sewage sludge, M. hapla or P. crenatus to soil inoculated with S. Typhimurium LT2 did not result in an improved survival in soil or internalization of lettuce plants. Copyright © 2017. Published by Elsevier Ltd.

  14. Enhancement of thermal neutron attenuation of nano-B4C, -BN dispersed neutron shielding polymer nanocomposites

    International Nuclear Information System (INIS)

    Kim, Jaewoo; Lee, Byung-Chul; Uhm, Young Rang; Miller, William H.

    2014-01-01

    Highlights: • Preparation of B 4 C and BN nanopowders using a simple ball milling process. • Homogeneous dispersion and strong adhesion of nano-B 4 C and -BN with polymer matrix. • Enhancement of mechanical properties of the nanocomposites compared to their micro counterparts. • Enhancement of thermal neutron attenuation of the nanocomposites. - Abstract: Nano-sized boron carbide (B 4 C) and boron nitride (BN) powder were prepared using ball milling. Micro- and milled nano-powders were melt blended with high density polyethylene (HDPE) using a polymer mixer followed by hot pressing to fabricate sheet composites. The tensile and flexural strengths of HDPE nanocomposites were ∼20% higher than their micro counterparts, while those for latter decreased compared to neat HDPE. Thermal neutrons attenuation of the prepared HDPE nanocomposites was evaluated using a monochromatic ∼0.025 eV neutron beam. Thermal neutron attenuation of the HDPE nanocomposites was greatly enhanced compared to their micro counterparts at the same B-10 areal densities. Monte Carlo n-Particles (MCNP) simulations based on the lattice structure modeling also shows the similar filler size dependent thermal neutron absorption

  15. Effect of sintering temperature on structure of C-B4C-SiC composites with silicon additive

    International Nuclear Information System (INIS)

    Wu Lijun; Academia Sinica, Shenyang; Huang Qizhong; Yang Qiaoqin; Zhao Lihu; Xu Zhongyu

    1996-01-01

    Carbon materials possess good electric conductivity, heat conductivity, corrosion-resistance, self-lubrication and hot-shocking resistance, and are easily machined. However, they have low mechanical strength, and are easily oxidized in air at high temperature. On the contrary, ceramic materials have high mechanical strength and hardness, and have good wear-resistance and oxidation-resistance. However, they have the shortages of poor thermal-shock resistance lubrication, and are difficult to machine. Therefore, carbon/ceramic composites with the advantages of both carbon and ceramic materials have been widely studied in the recent years. Huang prepared C-B 4 C-SiC composites with the free sintering method and the hot pressing method, and studied the effects of Si, Al, Al 2 O 3 , Ni and Ti additives on the properties of the composites. The results showed that these additives could improve the properties of the composites. Zhao et al. studies the structure of C-B 4 C-SiC composites with Si additive sintered at 2,000 C and found two c-center monoclinic phases. In this paper, the authors discussed the effect of the sintering temperature on the structure of C-B 4 C-SiC composites with Si additive by means of transmission electron microscope (TEM) and x-ray diffractometer (XRD)

  16. Mechanical performance optimization of neutron shielding material based on short carbon fiber reinforced B4C/epoxy resin

    International Nuclear Information System (INIS)

    Wang Peng; Tang Xiaobin; Chen Feida; Chen Da

    2013-01-01

    To satisfy engineering requirements for mechanics performance of neutron shielding material, short carbon fiber was used to reinforce the traditional containing B 4 C neutron shielding material and effects of fiber content, length and surface treatment to mechanics performance of material was discussed. Based on Americium-Beryllium neutron source, material's neutron shielding performance was tested. The result of experiment prove that tensile strength of material which the quality ratio of resin and fiber is 5:1 is comparatively excellent for 10wt% B 4 C of carbon fiber reinforced epoxy resin. The tensile properties of material change little with the fiber length ranged from 3-10 mm The treatment of fiber surface with silane coupling agent KH-550 can increase the tensile properties of materials by 20% compared with the untreated of that. A result of shielding experiment that the novel neutron shielding material can satisfy the neutron shielding requirements can be obtained by comparing with B 4 C/polypropylene materials. The material has good mechanical properties and wide application prospect. (authors)

  17. Rotational-mode component of the density of levels of nuclei with A approx-lt 150

    International Nuclear Information System (INIS)

    Rastopchin, E.M.; Svirin, M.I.; Smirenkin, G.N.

    1992-01-01

    Some difficulties which arise in the use of the generalized superfluid model to describe the density of levels in the region A approx-lt 150, as the result of an imperfect understanding of collective nuclear excitations, are discussed. One possible way to overcome these difficulties is examined. The idea is to depart from the conventional classification of collective nuclear properties and make use of small static deformations predicted theoretically and a corresponding rotational-mode component of the density of levels of these nuclei

  18. Improving containment mass and energy releases for CONTEMPT-LT/028 TU with RELAP5/MOD3

    International Nuclear Information System (INIS)

    DaSilva, H.C.; Choe, W.G.

    1996-01-01

    In order to obtain boundary conditions for RELAP5/MOD3 best estimate (BE) large break (LB) loss-of-coolant accident (LOCA) calculations, it is necessary to utilize a separate containment analysis code CONTEMPT-LT/028 TU, which in turn accepts mass and energy releases from the RELAP5/MOD3 calculation. When these boundary conditions are obtained, they are observed to be significantly lower than those reported in FSAR containment analyses. This motivates the present study, where RELAP5/MOD3 mass and energy releases are generated using the same assumptions listed in the FSAR containment calculations. Then CONTEMPT-LT/028 TU pressures and temperatures calculated with both sets of mass and energy releases are compared. It is seen that those obtained with the RELAP5/MOD3 input are still significantly lower, indicating a level of conservatism in the FSAR mass and energy releases that is even above that explicitly listed and also incorporated into the RELAP5/MOD3 calculation. An important conclusion from this finding is that Environmental Qualification (EQ) issues requiring containment re-analyses are likely to be easily resolved if new mass and energy releases are calculated with state-of-the-art LOCA codes modeling the entire reactor coolant system, even when conservative assumptions are incorporated

  19. Isolated Subclinical Hyperthyrotropinemia in Obese Children: Does Levothyroxine (LT4 Improve Weight Reduction during Combined Behavioral Therapy?

    Directory of Open Access Journals (Sweden)

    Pawel Matusik

    2015-01-01

    Full Text Available Objective. The study aim was to analyze whether anthropometrical parameters and TSH values in obese children with isolated subclinical hypothyroidism (IsHT treated with levothyroxine (LT4 and weight reduction program differ from those managed by dietary and behavior counselling only. Material and Methods. 51 obese children with IsHT, who were treated according to the same weight reduction program, were retrospectively analyzed. They were divided into two groups: Group 1, n=26, and Group 2, n=25, without or with LT4 therapy, respectively. Changes in anthropometrical (delta BMI z-score and hormonal (delta TSH status were analyzed at the first follow-up visit. Results. In both groups significant decrease of TSH and BMI z-score values were noted. TSH normalized in 80.9% of children from Group 1 versus 90.5% from Group 2, p = NS. Delta BMI z-score was insignificantly higher in Group 1 compared to Group 2. Delta TSH was significantly related to initial TSH level in children treated by lifestyle intervention program only. Conclusions. In obese children with sHT dietary-behavioral management intervention contributed to reduction of body mass index, irrespective of levothyroxine use. This finding suggests that moderately elevated levels of TSH are a consequence rather than cause of overweight and pharmacological treatment should be avoided.

  20. Clinical experience with EDAP LT-01+ extracorporeal shock wave lithotripsy for radiolucent stones; a report of 27 cases

    International Nuclear Information System (INIS)

    Rim, Hee Kwan; Kim, Ho Sung; Rim, Joung Sik

    1994-01-01

    Between February 1990 and February 1993, Radiolucent stones of 27 renal units in 22 patients were treated by extracorporeal shock wave lithotripsy (ESWL) using the EDAP LT-01+. Intravenous urography was done in all patients for the diagnosis of radiolucent stones. Retrograde pyelography, ultrasonography and/or computed tomography was done, if needed. The locations of stones were kidney in 11(40.7 %), upper ureter in 8(29.6 %), lower ureter in 6(22.2 %), bladder in 1(3.7 %), ureteropelvic junction in 1(3.7 %). The average stone size was 10.9mm with a range of 5 to 32mm in maximum diameter. The average numbers of treatment were 2.7 sessions and average storage required was 34.8 in one session. The average treatment time was 40.4 minutes. All the patients showed complete removal of all calculous materials. Of 17 urinary stones analysed by chemical method, 8(47.1 %) were composed of uric acid, 5(29.4 %) of uric acid and calcium, 3 of phosphate and 1 of carbonate and phosphate. Therefore, we conclude that ESWL with EDAP LT-01+ lithotriptor is considered to be an effective noninvasive procedure for treatment of radiolucent stones. (Author)

  1. Alkaline pH Is a signal for optimal production and secretion of the heat labile toxin, LT in enterotoxigenic Escherichia coli (ETEC.

    Directory of Open Access Journals (Sweden)

    Lucia Gonzales

    Full Text Available Enterotoxigenic Escherichia coli (ETEC cause secretory diarrhea in children and travelers to endemic areas. ETEC spreads through the fecal-oral route. After ingestion, ETEC passes through the stomach and duodenum before it colonizes the lower part of the small intestine, exposing bacteria to a wide range of pH and environmental conditions. This study aimed to determine the impact of external pH and activity of the Cyclic AMP receptor protein (CRP on the regulation of production and secretion of heat labile (LT enterotoxin. ETEC strain E2863wt and its isogenic mutant E2863ΔCRP were grown in LBK media buffered to pH 5, 7 and 9. GM1 ELISA, cDNA and cAMP analyses were carried out on bacterial pellet and supernatant samples derived from 3 and 5 hours growth and from overnight cultures. We confirm that CRP is a repressor of LT transcription and production as has been shown before but we show for the first time that CRP is a positive regulator of LT secretion both in vitro and in vivo. LT secretion increased at neutral to alkaline pH compared to acidic pH 5 where secretion was completely inhibited. At pH 9 secretion of LT was optimal resulting in 600 percent increase of secreted LT compared to unbuffered LBK media. This effect was not due to membrane leakage since the bacteria were viable at pH 9. The results indicate that the transition to the alkaline duodenum and/or exposure to high pH close to the epithelium as well as activation of the global transcription factor CRP are signals that induce secretion of the LT toxin in ETEC.

  2. Radioimmunological detection of type-specific antibodies against polioviruses 1, 2 and 3 as well as the B4 Coxsackie virus. Radioimmunologischer Nachweis typenspezifischer Antikoerper gegen Poliovirus 1, 2 und 3 und gegen Coxsackievirus B4

    Energy Technology Data Exchange (ETDEWEB)

    Hartung Goetze, C.F.

    1985-06-27

    A simple radioimmunological procedure is described in which the qualitative and quantitative determination of serum antibodies against polioviruses 1, 2 and 3 and against the B4 Coxsackie virus is based on adsorption chromatography. It is comparable to the neutralisation test as regards sensitivity and specifity and has the additional advantage of being the faster, simplier and cheaper of those two methods. The radioactive labelling of the virsuses was achieved with types of 32 P or 3 H that had favourable half-lives and would thus permit the labelled compounds to be stored for prolonged periods of time. The immunological statuses and antibody titres of sera obtained from 45 female volunteers, where the vaccinations against polymyelitis had mostly been carried out by the oral route, showed remarkably little changes, which was evident from the fact that the proportion of study participants found to have antibodies against all three serological types was 91% in 1970 and still as large at 89% in 1983. When a total of 1016 sera were screened for Coxsackie virus B4, no age dependency could be determined for the age range between 5 and 35 years, nor were there any differences seen between the individual residential areas. (TRV).

  3. High-pressure synthesis and characterization of new actinide borates, AnB4O8 (An=Th, U).

    Science.gov (United States)

    Hinteregger, Ernst; Hofer, Thomas S; Heymann, Gunter; Perfler, Lukas; Kraus, Florian; Huppertz, Hubert

    2013-11-18

    New actinide borates ThB4O8 and UB4O8 were synthesized under high-pressure, high-temperature conditions (5.5 GPa/1100 °C for thorium borate, 10.5 GPa/1100 °C for the isotypic uranium borate) in a Walker-type multianvil apparatus from their corresponding actinide oxide and boron oxide. The crystal structure was determined on basis of single-crystal X-ray diffraction data that were collected at room temperature. Both compounds crystallized in the monoclinic space group C2/c (Z=4). Lattice parameters for ThB4O8: a=1611.3(3), b=419.86(8), c=730.6(2) pm; β=114.70(3)°; V=449.0(2) Å(3); R1=0.0255, wR2=0.0653 (all data). Lattice parameters for UB4O8: a=1589.7(3), b=422.14(8), c=723.4(2) pm; β=114.13(3)°; V=443.1(2) Å(3); R1=0.0227, wR2=0.0372 (all data). The new AnB4O8 (An=Th, U) structure type is constructed from corner-sharing BO4 tetrahedra, which form layers in the bc plane. One of the four independent oxygen atoms is threefold-coordinated. The actinide cations are located between the boron-oxygen layers. In addition to Raman spectroscopic investigations, DFT calculations were performed to support the assignment of the vibrational bands. © 2013 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA. This isan open access article under the terms of the Creative Commons AttributionLicense, which permits use, distribution and reproduction in any medium,provided the original work is properly cited.

  4. Dwarfism with joint laxity in Friesian horses is associated with a splice site mutation in B4GALT7.

    Science.gov (United States)

    Leegwater, Peter A; Vos-Loohuis, Manon; Ducro, Bart J; Boegheim, Iris J; van Steenbeek, Frank G; Nijman, Isaac J; Monroe, Glen R; Bastiaansen, John W M; Dibbits, Bert W; van de Goor, Leanne H; Hellinga, Ids; Back, Willem; Schurink, Anouk

    2016-10-28

    Inbreeding and population bottlenecks in the ancestry of Friesian horses has led to health issues such as dwarfism. The limbs of dwarfs are short and the ribs are protruding inwards at the costochondral junction, while the head and back appear normal. A striking feature of the condition is the flexor tendon laxity that leads to hyperextension of the fetlock joints. The growth plates of dwarfs display disorganized and thickened chondrocyte columns. The aim of this study was to identify the gene defect that causes the recessively inherited trait in Friesian horses to understand the disease process at the molecular level. We have localized the genetic cause of the dwarfism phenotype by a genome wide approach to a 3 Mb region on the p-arm of equine chromosome 14. The DNA of two dwarfs and one control Friesian horse was sequenced completely and we identified the missense mutation ECA14:g.4535550C > T that cosegregated with the phenotype in all Friesians analyzed. The mutation leads to the amino acid substitution p.(Arg17Lys) of xylosylprotein beta 1,4-galactosyltransferase 7 encoded by B4GALT7. The protein is one of the enzymes that synthesize the tetrasaccharide linker between protein and glycosaminoglycan moieties of proteoglycans of the extracellular matrix. The mutation not only affects a conserved arginine codon but also the last nucleotide of the first exon of the gene and we show that it impedes splicing of the primary transcript in cultured fibroblasts from a heterozygous horse. As a result, the level of B4GALT7 mRNA in fibroblasts from a dwarf is only 2 % compared to normal levels. Mutations in B4GALT7 in humans are associated with Ehlers-Danlos syndrome progeroid type 1 and Larsen of Reunion Island syndrome. Growth retardation and ligamentous laxity are common manifestations of these syndromes. We suggest that the identified mutation of equine B4GALT7 leads to the typical dwarfism phenotype in Friesian horses due to deficient splicing of transcripts of

  5. SPOTS4. Group data library and computer code, preparing ENDF/B-4 data for input to LEOPARD

    International Nuclear Information System (INIS)

    Kim, J.D.; Lee, J.T.

    1981-09-01

    The magnetic tape SPOTS4 contains in file 1 a data library to be used as input to the SPOTS4 program which is contained in file 2. The data library is based on ENDF/B-4 and consists of two parts in TEMPEST format (246 groups) and MUFT format (54 groups) respectively. From this library the SPOTS4 program produces a 172 + 54 group library for LEOPARD input. A copy of the magnetic tape is available from the IAEA Nuclear Data Section. (author)

  6. Quadrupolar frustration in shastry-sutherland lattice of DyB4 studied by resonant x-ray scattering

    International Nuclear Information System (INIS)

    Okuyama, Daisuke; Matsumura, Takeshi; Nakao, Hironori; Murakami, Youichi

    2005-01-01

    We have observed geometrical frustration of quadrupolar and magnetic moments in dysprosium tetraboride, DyB 4 , where the rare-earth sites form a Shastry-Sutherland lattice. Resonant X-ray scattering at the L III absorption edge of Dy was utilized. Analysis of the energy, polarization, temperature, and azimuthal-angle dependences of the E1 resonance of the (100) forbidden reflection show that the magnetic and quadrupolar components within the frustrated c plane have a short-range correlation, suggesting that the moments are fluctuating. In contrast, the basic antiferromagnetic component along the c-axis has a long-range order. (author)

  7. Polarized Structure Function $\\sigma_{LT'}$ for $p({\\vec e},e'K^+)\\Lambda$ in the Nucleon Resonance Region

    Energy Technology Data Exchange (ETDEWEB)

    Nasseripour, Rakhsha; Raue, Brian; Ambrozewicz, Pawel; Carman, Daniel; Amaryan, Moscov; Amaryan, Moskov; Anciant, Eric; Anghinolfi, Marco; Asavapibhop, Burin; Asryan, Gegham; Audit, Gerard; Auger, Thierry; Avagyan, Harutyun; Baghdasaryan, Hovhannes; Baillie, Nathan; Ball, J.P.; Ball, Jacques; Ball, J.P.; Ball, Jacques; Ball, J.P.; Ball, Jacques; Ball, J.P.; Ball, Jacques; Baltzell, Nathan; Barrow, Steve; Battaglieri, Marco; Beard, Kevin; Bedlinskiy, Ivan; Bektasoglu, Mehmet; Bellis, Matthew; Benmouna, Nawal; Berman, Barry; Biselli, Angela; Blaszczyk, Lukasz; Bonner, Billy; Bouchigny, Sylvain; Boyarinov, Sergey; Bradford, Robert; Branford, Derek; Briscoe, William; Brooks, William; Burkert, Volker; Butuceanu, Cornel; Calarco, John; Careccia, Sharon; Casey, Liam; Cetina, Catalina; Chen, Shifeng; Cheng, Lu; Cole, Philip; Collins, Patrick; Coltharp, Philip; Cords, Dieter; Corvisiero, Pietro; Crabb, Donald; Crede, Volker; Dale, Daniel; Dashyan, Natalya; De Masi, Rita; De Vita, Raffaella; De Sanctis, Enzo; Degtiarenko, Pavel; Dennis, Lawrence; Deur, Alexandre; Dhuga, Kalvir; Dickson, Richard; Djalali, Chaden; Dodge, Gail; Doughty, David; Dragovitsch, Peter; Dugger, Michael; Dytman, Steven; Dzyubak, Oleksandr; Egiyan, Hovanes; Egiyan, Kim; Elfassi, Lamiaa; Elouadrhiri, Latifa; Eugenio, Paul; Fatemi, Renee; Fedotov, Gleb; Feldman, Gerald; Feuerbach, Robert; Forest, Tony; Fradi, Ahmed; Funsten, Herbert; Garcon, Michel; Gavalian, Gagik; Gevorgyan, Nerses; Gilfoyle, Gerard; Giovanetti, Kevin; Girard, Pascal; Girod, Francois-Xavier; Goetz, John; Gothe, Ralf; Gothe, Ralf; Griffioen, Keith; Guidal, Michel; Guillo, Matthieu; Guler, Nevzat; Guo, Lei; Gyurjyan, Vardan; Hafidi, Kawtar; Hakobyan, Hayk; Hanretty, Charles; Hardie, John; Heddle, David; Hersman, F.; Hicks, Kenneth; Hleiqawi, Ishaq; Holtrop, Maurik; Hu, Jicun; Hyde, Charles; Ilieva, Yordanka; Ireland, David; Ishkhanov, Boris; Isupov, Evgeny; Ito, Mark; Jenkins, David; Jo, Hyon-Suk; Johnstone, John; Joo, Kyungseon; Juengst, Henry; Kalantarians, Narbe; Kellie, James; Khandaker, Mahbubul; Kim, Kui; Kim, Kyungmo; Kim, Wooyoung; Klein, Andreas; Klein, Franz; Kossov, Mikhail; Krahn, Zebulun; Kramer, Laird; Kubarovsky, Valery; Kuhn, Joachim; Kuhn, Sebastian; Kuleshov, Sergey; Kuznetsov, Viacheslav; Lachniet, Jeff; Laget, Jean; Langheinrich, Jorn; Lawrence, David; Livingston, Kenneth; Lu, Haiyun; Lukashin, Konstantin; MacCormick, Marion; Manak, Joseph; Markov, Nikolai; Mattione, Paul; McAleer, Simeon; McKinnon, Bryan; McNabb, John; Mecking, Bernhard; Mestayer, Mac; Meyer, Curtis; Mibe, Tsutomu; Mikhaylov, Konstantin; Minehart, Ralph; Mirazita, Marco; Miskimen, Rory; Mokeev, Viktor; Moreno, Brahim; Moriya, Kei; Morrow, Steven; Moteabbed, Maryam; Mueller, James; Munevar Espitia, Edwin; Mutchler, Gordon; Nadel-Turonski, Pawel; Niccolai, Silvia; Niculescu, Gabriel; Niculescu, Maria-Ioana; Niczyporuk, Bogdan; Niroula, Megh; Niyazov, Rustam; Nozar, Mina; Osipenko, Mikhail; Ostrovidov, Alexander; Park, Kijun; Pasyuk, Evgueni; Paterson, Craig; Pereira, Sergio; Peterson, Gerald; Philips, Sasha; Pierce, Joshua; Pivnyuk, Nikolay; Pocanic, Dinko; Pogorelko, Oleg; Pozdnyakov, Sergey; Preedom, Barry; Price, John; Procureur, Sebastien; Prok, Yelena; Protopopescu, Dan; Qin, Liming; Riccardi, Gregory; Ricco, Giovanni; Ripani, Marco; Ritchie, Barry; Rosner, Guenther; Rossi, Patrizia; Rubin, Philip; Sabatie, Franck; Salamanca, Julian; Salgado, Carlos; Santoro, Joseph; Sapunenko, Vladimir; Sayre, Donald; Schumacher, Reinhard; Serov, Vladimir; Shafi, Aziz; Sharabian, Youri; Sharov, Dmitri; Shvedunov, Nikolay; Simionatto, Sebastio; Skabelin, Alexander; Smith, Elton; Smith, Lee; Sober, Daniel; Sokhan, Daria; Stavinsky, Aleksey; Stepanyan, Samuel; Stepanyan, Stepan; Stokes, Burnham; Stoler, Paul; Strakovski, Igor; Strauch, Steffen; Taiuti, Mauro; Taylor, Shawn; Tedeschi, David; Thoma, Ulrike; Thompson, Richard; Tkabladze, Avtandil; Tkachenko, Svyatoslav; Ungaro, Maurizio; Vineyard, Michael; Vlassov, Alexander; Wang,

    2008-06-01

    The first measurements of the polarized structure function $\\sigma_{LT'}$ for the reaction $p(\\vec e,e'K^+)\\Lambda$ in the nucleon resonance region are reported. Measurements are included from threshold up to $W$=2.05 GeV for central values of $Q^2$ of 0.65 and 1.00 GeV$^2$, and nearly the entire kaon center-of-mass angular range. $\\sigma_{LT'}$ is the imaginary part of the longitudinal-transverse response and is expected to be sensitive to interferences between competing intermediate s-channel resonances, as well as resonant and non-resonant processes. The results for $\\sigma_{LT'}$ are comparable in magnitude to previously reported results from CLAS for $\\sigma_{LT}$, the real part of the same response. An intriguing sign change in $\\sigma_{LT'}$ is observed in the high $Q^2$ data at $W\\approx 1.9$ GeV. Comparisons to several existing model predictions are shown.

  8. Decreased calcium pump expression in human erythrocytes is connected to a minor haplotype in the ATP2B4 gene.

    Science.gov (United States)

    Zámbó, Boglárka; Várady, György; Padányi, Rita; Szabó, Edit; Németh, Adrienn; Langó, Tamás; Enyedi, Ágnes; Sarkadi, Balázs

    2017-07-01

    Plasma membrane Ca 2+ -ATPases are key calcium exporter proteins in most tissues, and PMCA4b is the main calcium transporter in the human red blood cells (RBCs). In order to assess the expression level of PMCA4b, we have developed a flow cytometry and specific antibody binding method to quantitatively detect this protein in the erythrocyte membrane. Interestingly, we found several healthy volunteers showing significantly reduced expression of RBC-PMCA4b. Western blot analysis of isolated RBC membranes confirmed this observation, and indicated that there are no compensatory alterations in other PMCA isoforms. In addition, reduced PMCA4b levels correlated with a lower calcium extrusion capacity in these erythrocytes. When exploring the potential genetic background of the reduced PMCA4b levels, we found no missense mutations in the ATP2B4 coding regions, while a formerly unrecognized minor haplotype in the predicted second promoter region closely correlated with lower erythrocyte PMCA4b protein levels. In recent GWA studies, SNPs in this ATP2B4 haplotype have been linked to reduced mean corpuscular hemoglobin concentrations (MCHC), and to protection against malaria infection. Our data suggest that an altered regulation of gene expression is responsible for the reduced RBC-PMCA4b levels that is probably linked to the development of human disease-related phenotypes. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Influence of growth medium on cometabolic degradation of polycyclic aromatic hydrocarbons by Sphingomonas sp. strain PheB4

    Energy Technology Data Exchange (ETDEWEB)

    Zhong Yin; Wang Xiaowei [Sun Yat-Sen Univ., Guangzhou (China). State Key Lab. of Biocontrol; Futian-CityU Mangrove Research and Development Centre, Shenzhen (China). Futian National Nature Reserve; Luan Tiangang; Lan Chongyu [Sun Yat-Sen Univ., Guangzhou (China). State Key Lab. of Biocontrol; Tam, N.F.Y. [Futian-CityU Mangrove Research and Development Centre, Shenzhen (China). Futian National Nature Reserve; City Univ. of Hong Kong, Kowloon (China). Dept. of Biology and Chemistry

    2007-05-15

    The influence of growth medium on cometabolic degradation of polycyclic aromatic hydrocarbons (PAHs) was investigated when Sphingomonas sp. strain PheB4 isolated from surface mangrove sediments was grown in either phenanthrene-containing mineral salts medium (PMSM) or nutrient broth (NB). The NB-grown culture exhibited a more rapid cometabolic degradation of single and mixed non-growth substrate PAHs compared to the PMSM-grown culture. The concentrations of PAH metabolites were also lower in NB-grown culture than in PMSM-grown culture, suggesting that NB-grown culture removed metabolites at a faster rate, particularly, for metabolites produced from cometabolic degradation of a binary mixture of PAHs. Cometabolic pathways of single PAH (anthracene, fluorene, or fluoranthene) in NB-grown culture showed similarity to that in PMSM-grown culture. However, cometabolic pathways of mixed PAHs were more diverse in NB-grown culture than that in PMSM-grown culture. These results indicated that nutrient rich medium was effective in enhancing cometabolic degradation of mixed PAHs concomitant with a rapid removal of metabolites, which could be useful for the bioremediation of mixed PAHs contaminated sites using Sphingomonas sp. strain PheB4. (orig.)

  10. Structural annotation of Beta-1,4-N-acetyl galactosaminyltransferase 1 (B4GALNT1) causing Hereditary Spastic Paraplegia 26.

    Science.gov (United States)

    Dad, Rubina; Malik, Uzma; Javed, Aneela; Minassian, Berge A; Hassan, Muhammad Jawad

    2017-08-30

    Beta-1,4-N-acetyl galactosaminyltransferase 1, B4GALNT1, is a GM2/GD2 synthase, involved in the expression of glycosphingolipids (GSLs) containing sialic acid. Mutations in the gene B4GALNT1 cause Hereditary Spastic Paraplegia 26 (HSP26). In present study we have made attempt to predict the potential structural of the human B4GALNT1 protein. The results illustrated that the amino acid sequences of B4GALNT1 are not 100% conserved among selected twenty species. One signal peptide and one transmembrane domain predicted in human wild type B4GALNT1 protein with aliphatic index of 92.76 and theoretical (iso-electric point) pI of 8.93. It was a kind of unstable protein with Grand average of hydropathicity (GRAVY) of -0.127. Various post-translational modifications were also predicted to exist in B4GALNT1 and predicted to interact with different proteins including ST8SIA5, SLC33A1, GLB1 and others. In the final round, reported missense mutations have shown the further decrease in stability of the protein. This in-silico analysis of B4GALNT1 protein will provide the basis for the further studies on structural variations and biological pathways involving B4GALNT1 in the HSP26. Copyright © 2017. Published by Elsevier B.V.

  11. Discovery of a visual T-dwarf triple system and binarity at the L/T transition

    Energy Technology Data Exchange (ETDEWEB)

    Radigan, Jacqueline [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Jayawardhana, Ray [Department of Astronomy and Astrophysics, University of Toronto, 50 St. George Street, Toronto, ON M5S 3H4 (Canada); Lafrenière, David [Département de Physique, Université de Montréal, C.P. 6128 Succ. Centre-Ville, Montréal, QC H3C 3J7 (Canada); Dupuy, Trent J. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Liu, Michael C. [Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States); Scholz, Alexander, E-mail: radigan@stsci.edu [School of Physics and Astronomy, University of St Andrews, North Haugh, St Andrews, KY169SS (United Kingdom)

    2013-11-20

    We present new high contrast imaging of eight L/T transition brown dwarfs (BDs) using the NIRC2 camera on the Keck II telescope. One of our targets, the T3.5 dwarf 2MASS J08381155+1511155, was resolved into a hierarchal triple with projected separations of 2.5 ± 0.5 AU and 27 ± 5 AU for the BC and A(BC) components, respectively. Resolved OSIRIS spectroscopy of the A(BC) components confirms that all system members are T dwarfs. The system therefore constitutes the first triple T-dwarf system ever reported. Using resolved photometry to model the integrated-light spectrum, we infer spectral types of T3 ± 1, T3 ± 1, and T4.5 ± 1 for the A, B, and C components, respectively. The uniformly brighter primary has a bluer J – K{sub s} color than the next faintest component, which may reflect a sensitive dependence of the L/T transition temperature on gravity, or alternatively divergent cloud properties among components. Relying on empirical trends and evolutionary models we infer a total system mass of 0.034-0.104 M {sub ☉} for the BC components at ages of 0.3-3 Gyr, which would imply a period of 12-21 yr assuming the system semimajor axis to be similar to its projection. We also infer differences in effective temperatures and surface gravities between components of no more than ∼150 K and ∼0.1 dex. Given the similar physical properties of the components, the 2M0838+15 system provides a controlled sample for constraining the relative roles of effective temperature, surface gravity, and dust clouds in the poorly understood L/T transition regime. For an age of 3 Gyr we estimate a binding energy of ∼20 × 10{sup 41} erg for the wide A(BC) pair, which falls above the empirical minimum found for typical BD binaries, and suggests that the system may have been able to survive a dynamical ejection during formation. Combining our imaging survey results with previous work we find an observed binary fraction of 4/18 or 22{sub −8}{sup +10}% for unresolved spectral types

  12. A comparison study on the densification behavior and mechanical properties of gelcast vs conventionally formed B4C sintered conventionally and by microwaves

    International Nuclear Information System (INIS)

    Menchhofer, P.A.; Kiggans, J.O.; Morrow, M.S.; Schechter, D.E.

    1996-01-01

    The utilization of microwave energy for reaching high temperatures necessary to densify B 4 C powder is compared with conventional means of sintering by evaluating the mechanical properties after densification. Microwave energy has been shown to be an effective means for achieving high sintered densities, even though temperatures of ∼ 2,250 C are required. In this study, green preforms of B 4 C specimens were sintered by both conventional and microwave heating. This study also utilized an advanced forming method called ''Gelcasting'' developed at ORNL. Gelcasting is a fluid forming process whereby high solids suspensions of powders containing dissolved monomers are cast into a mold, then polymerized or ''gelled'' in situ. This investigation compares microstructures and mechanical properties of both Gelcast B 4 C and ''conventionally'' die-pressed B 4 C. The microstructures and final mechanical properties of B 4 C specimens are discussed

  13. “Distributed hybrid” MH–CGH2 system for hydrogen storage and its supply to LT PEMFC power modules

    Energy Technology Data Exchange (ETDEWEB)

    Lototskyy, M., E-mail: mlototskyy@uwc.ac.za [HySA Systems Competence Centre, South African Institute for Advanced Materials Chemistry, Faculty of Natural Sciences, University of the Western Cape, Private Bag X17, Bellville 7535 (South Africa); Tolj, I.; Davids, M.W.; Bujlo, P. [HySA Systems Competence Centre, South African Institute for Advanced Materials Chemistry, Faculty of Natural Sciences, University of the Western Cape, Private Bag X17, Bellville 7535 (South Africa); Smith, F. [Impala Platinum Ltd, Springs (South Africa); Pollet, B.G. [HySA Systems Competence Centre, South African Institute for Advanced Materials Chemistry, Faculty of Natural Sciences, University of the Western Cape, Private Bag X17, Bellville 7535 (South Africa)

    2015-10-05

    Highlights: • Prototype hydrogen storage and supply system for LTPEMFC applications was developed. • Combination of MH and CGH2 tanks with common gas manifold was used. • Thermal coupling of fuel cell stack and MH tank was applied. • The system uses AB2-type MH; H2 equilibrium pressure ∼10 bar at room temperature. • Shorter H2 charge time and stable H2 supply at a fluctuating load were observed. - Abstract: This paper describes the layout and presents the results of the testing of a novel prototype “distributed hybrid” hydrogen storage and supply system that has the potential to be used for Low Temperature Proton Exchange Membrane Fuel Cell (LT-PEMFC) applications. The system consists of individual Metal Hydride (MH) and Compressed Gas (CGH2) tanks with common gas manifold, and a thermal management system where heat exchanger of the liquid heated-cooled MH tank is integrated with the cooling system of the LT-PEMFC BoP. The MH tank is filled with a medium-stability AB{sub 2}-type MH material (H{sub 2} equilibrium pressure of about 10 bar at room temperature). This innovative solution allows for (i) an increase in hydrogen storage capacity of the whole gas storage system and the reduction of H{sub 2} charge pressure; (ii) shorter charging times in the refuelling mode and smoother peaks of H{sub 2} consumption during its supply to the fuel cell stack; (iii) the use of standard parts with simple layout and lower costs; and (iv) adding flexibility in the layout and placement of the components of the hydrogen storage and supply system.

  14. “Distributed hybrid” MH–CGH2 system for hydrogen storage and its supply to LT PEMFC power modules

    International Nuclear Information System (INIS)

    Lototskyy, M.; Tolj, I.; Davids, M.W.; Bujlo, P.; Smith, F.; Pollet, B.G.

    2015-01-01

    Highlights: • Prototype hydrogen storage and supply system for LTPEMFC applications was developed. • Combination of MH and CGH2 tanks with common gas manifold was used. • Thermal coupling of fuel cell stack and MH tank was applied. • The system uses AB2-type MH; H2 equilibrium pressure ∼10 bar at room temperature. • Shorter H2 charge time and stable H2 supply at a fluctuating load were observed. - Abstract: This paper describes the layout and presents the results of the testing of a novel prototype “distributed hybrid” hydrogen storage and supply system that has the potential to be used for Low Temperature Proton Exchange Membrane Fuel Cell (LT-PEMFC) applications. The system consists of individual Metal Hydride (MH) and Compressed Gas (CGH2) tanks with common gas manifold, and a thermal management system where heat exchanger of the liquid heated-cooled MH tank is integrated with the cooling system of the LT-PEMFC BoP. The MH tank is filled with a medium-stability AB 2 -type MH material (H 2 equilibrium pressure of about 10 bar at room temperature). This innovative solution allows for (i) an increase in hydrogen storage capacity of the whole gas storage system and the reduction of H 2 charge pressure; (ii) shorter charging times in the refuelling mode and smoother peaks of H 2 consumption during its supply to the fuel cell stack; (iii) the use of standard parts with simple layout and lower costs; and (iv) adding flexibility in the layout and placement of the components of the hydrogen storage and supply system

  15. Characterization and Validation of the LT-SYS Copper Assay on a Roche Cobas 8000 c502 Analyzer.

    Science.gov (United States)

    Kraus, F Bernhard; Mischereit, Marlies; Eller, Christoph; Ludwig-Kraus, Beatrice

    2017-02-01

    Validation of the LT-SYS quantitative in vitro copper assay on a Roche Cobas 8000 c502 analyzer and comparison with a BIOMED assay on a Roche Cobas Mira analyzer. Imprecision and bias were quantified at different concentration levels (serum and plasma) over a 20-day period. Linearity was assessed covering a range from 4.08 µmol/L to 33.8 µmol/L. Limit of blank (LoB) and limit of detection (LoD) were established based on a total of 120 blank and low-level samples. The method comparison was based on 58 plasma samples. Within-run imprecision ranged from 0.7% to 1.2% and within-laboratory imprecision from 1.4% to 3.3%. Relative bias for the 2 serum pools with known target values was less than 2.5%. The assay did not deviate from linearity over the tested measuring range. LoB and LoD were 0.12 µmol/L and 0.23 µmol/L, respectively. The method comparison revealed an average deviation of 11.5% (2.016 µmol/L), and the linear regression fit was y = 1.464 + 0.795x. The LT-SYS copper assay characterized in this study showed a fully acceptable performance with good degrees of imprecision and bias, no deviation from linearity in the relevant measuring rangem, and very low LoB and LoD. © American Society for Clinical Pathology, 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  16. Combination of Dll4/Notch and Ephrin-B2/EphB4 targeted therapy is highly effective in disrupting tumor angiogenesis

    International Nuclear Information System (INIS)

    Djokovic, Dusan; Gill, Parkash S; Duarte, Antonio; Trindade, Alexandre; Gigante, Joana; Badenes, Marina; Silva, Lilliana; Liu, Ren; Li, Xiuqing; Gong, Ming; Krasnoperov, Valery

    2010-01-01

    Dll4/Notch and Ephrin-B2/EphB4 pathways play critical roles in tumor vessel development and maturation. This study evaluates the efficacy of the inhibition of both signaling pathways, alone and in combination, in reducing the growth of an autochthonous mouse tumor and assesses potential adverse effects. We used the transgenic RIP1-Tag2 tumor model to study the effects of 1) inhibition of Dll4/Notch by either Dll4 allelic deletion or use of a soluble extracellular Dll4 (sDll4), 2) inhibition of Ephrin-B2/EphB4 signaling by a soluble extracellular EphB4 fused to albumin (sEphB4-Alb), and 3) inhibition of both pathways by sEphB4-Alb combined with either Dll4 allelic deletion or sDll4. To investigate adverse effects, we used inducible endothelial-specific Dll4 knock-out mice, treated with sEphB4-Alb, and carried out histopathological analysis. Dll4 allele deletion or soluble Dll4 treatment resulted in increased tumor vessel density, reduced mural cell recruitment and vessel perfusion which resulted in reduced tumor size. The soluble EphB4 instead reduced vessel density and vessel perfusion, leading to reduction of tumor size. Greater efficacy was observed when sEphB4-Alb was combined with either Dll4 allele deletion or sDll4 in regards to tumor size, vessel perfusion and mural cell recruitment. Induced endothelial specific Dll4 loss-of-function caused hepatic vascular alterations, which were prevented by concomitant sEphB4-Alb treatment. Combination targeting of Dll4/Notch and Ephrin-B2/EphB4 has potential for clinical investigation, providing cumulative efficacy and increased safety over Dll4/Notch inhibition alone

  17. Comparison of the CORA-12, 13, 17 experiments and B4 effect on the flooding behavior of BWR bundles

    International Nuclear Information System (INIS)

    Hagen, S.; Sepold, L.; Wallenfels, K.P.; Hofmann, P.; Noack, V.; Schanz, G.; Schumacher, G.

    1995-01-01

    The CORA quench experiments 12, 13 (PWR) and 17 (BWR) are in agreement with LOFT 2 and TMI: Flooding of hot Zircaloy clad fuel rods does not result in an immediate cooldown of the bundle, but produces remarkable temporary temperature increase, connected to a strong peak in hydrogen production. The PWR tests CORA 12 and CORA 13 are of the same geometrical arrangement and test conduct, with the exception of the shorter time between power shutdown and quench initiation for CORA 13. A higher temperature of the bundle at start of quenching was the consequence. BWR test CORA 17 - with B 4 C absorber and additional Zircaloy channel box walls - was in respect to the delay-time between power shutdown and start of quenching similar to test CORA 12. All tests showed during the quench phase the temporary temperature increase, correlated to a hydrogen peak. The CORA 17 test resulted immediately after quenching in a modest increase for 20 s and changed then in a steep increase, resulting in the highest temperature and hydrogen peaks of the three tests. CORA 17 also showed a temperature increase in the lower part of the bundle, in contrast to CORA 12 and CORA 13 with temperature increase only in the upper half of the bundle. We interpret this earlier starting and stronger reaction due to the influence of the boron carbide, the absorber material of the BWR test. B 4 C has an exothermic reaction rate 4 to 9 times larger than Zry and produces 5 to 6,6 times more hydrogen. Probably the hot remained columns of B 4 C (seen in the non-quench test CORA 16) react early in the quench process with the increased upcoming steam. The bundle temperature raised by this reaction increases the reaction rate (exponential dependency) of the remaining metallic Zry. Due to the larger amount of Zry in the BWR bundle (channel box walls) and the smaller steam input during the heatup phase (2 g/s instead of 6 g/s) more metallic Zry can have survived oxidation during the heatup phase. (orig./HP)

  18. Processing and characterization of laser sintered hybrid B4C/cBN reinforced Ti-based metal matrix composite

    Science.gov (United States)

    Gupta, Ankit; Hussain, Manowar; Misra, Saurav; Das, Alok Kumar; Mandal, Amitava

    2018-06-01

    The purpose of this study is to make a boron carbide (B4C) and cubic boron nitride (cBN) reinforced Ti6Al4V metal matrix composites (MMC's) by direct metal laser sintering (DMLS) technique using the continuous wave (CW) SPI fiber laser and to check the feasibility of the formation of three dimensional objects by this process. For this study, the process parameters like laser power density (3.528-5.172 W/cm2 (×104), scanning speed (3500-4500 mm/min), composition of the reinforced materials B4C (5-25% by volume) and cBN (3% by volume) were taken as input variables and hatching gap (0.2 mm), spot diameter (0.4 mm), layer thickness (0.4 mm) were taken as constant. It was analyzed that surface characteristic, density and the mechanical properties of sintered samples were greatly influenced by varying the input process parameters. Field emission scanning electron microscopy (FESEM), Energy dispersive X-ray spectroscopy (EDX) and X-Ray diffraction (XRD) were performed for microstructural analysis, elemental analysis, and recognition of intermetallic compounds respectively. Mechanical properties like micro-hardness & wear rate were examined by Vickers micro-hardness tester & pin on disc arrangement respectively. From hardness tests, it was observed that hardness property of the sintered specimens was increased as compared to the parent material. The XRD results show that there is a good affinity between Ti6Al4V-B4C-cBN to produce various intermetallic compounds which themselves enhance the mechanical properties of the samples. From FESEM analysis, we can conclude that there is a uniform distribution of reinforcements in the titanium alloy matrix. Furthermore, the coefficient of friction (COF) was characterized by the irregular pattern and it tends to decrease with an increase in the volume % of reinforcement. The results obtained in this work may be useful in preparing the MMC's with improved mechanical properties and overall characteristics.

  19. Clonal relatedness of enterotoxigenic Escherichia coli (ETEC) strains expressing LT and CS17 isolated from children with diarrhoea in La Paz, Bolivia.

    Science.gov (United States)

    Rodas, Claudia; Klena, John D; Nicklasson, Matilda; Iniguez, Volga; Sjöling, Asa

    2011-01-01

    Enterotoxigenic Escherichia coli (ETEC) is a major cause of traveller's and infantile diarrhoea in the developing world. ETEC produces two toxins, a heat-stable toxin (known as ST) and a heat-labile toxin (LT) and colonization factors that help the bacteria to attach to epithelial cells. In this study, we characterized a subset of ETEC clinical isolates recovered from Bolivian children under 5 years of age using a combination of multilocus sequence typing (MLST) analysis, virulence typing, serotyping and antimicrobial resistance test patterns in order to determine the genetic background of ETEC strains circulating in Bolivia. We found that strains expressing the heat-labile (LT) enterotoxin and colonization factor CS17 were common and belonged to several MLST sequence types but mainly to sequence type-423 and sequence type-443 (Achtman scheme). To further study the LT/CS17 strains we analysed the nucleotide sequence of the CS17 operon and compared the structure to LT/CS17 ETEC isolates from Bangladesh. Sequence analysis confirmed that all sequence type-423 strains from Bolivia had a single nucleotide polymorphism; SNP(bol) in the CS17 operon that was also found in some other MLST sequence types from Bolivia but not in strains recovered from Bangladeshi children. The dominant ETEC clone in Bolivia (sequence type-423/SNP(bol)) was found to persist over multiple years and was associated with severe diarrhoea but these strains were variable with respect to antimicrobial resistance patterns. The results showed that although the LT/CS17 phenotype is common among ETEC strains in Bolivia, multiple clones, as determined by unique MLST sequence types, populate this phenotype. Our data also appear to suggest that acquisition and loss of antimicrobial resistance in LT-expressing CS17 ETEC clones is more dynamic than acquisition or loss of virulence factors.

  20. Clonal Relatedness of Enterotoxigenic Escherichia coli (ETEC) Strains Expressing LT and CS17 Isolated from Children with Diarrhoea in La Paz, Bolivia

    Science.gov (United States)

    Rodas, Claudia; Klena, John D.; Nicklasson, Matilda; Iniguez, Volga; Sjöling, Åsa

    2011-01-01

    Background Enterotoxigenic Escherichia coli (ETEC) is a major cause of traveller's and infantile diarrhoea in the developing world. ETEC produces two toxins, a heat-stable toxin (known as ST) and a heat-labile toxin (LT) and colonization factors that help the bacteria to attach to epithelial cells. Methodology/Principal Findings In this study, we characterized a subset of ETEC clinical isolates recovered from Bolivian children under 5 years of age using a combination of multilocus sequence typing (MLST) analysis, virulence typing, serotyping and antimicrobial resistance test patterns in order to determine the genetic background of ETEC strains circulating in Bolivia. We found that strains expressing the heat-labile (LT) enterotoxin and colonization factor CS17 were common and belonged to several MLST sequence types but mainly to sequence type-423 and sequence type-443 (Achtman scheme). To further study the LT/CS17 strains we analysed the nucleotide sequence of the CS17 operon and compared the structure to LT/CS17 ETEC isolates from Bangladesh. Sequence analysis confirmed that all sequence type-423 strains from Bolivia had a single nucleotide polymorphism; SNPbol in the CS17 operon that was also found in some other MLST sequence types from Bolivia but not in strains recovered from Bangladeshi children. The dominant ETEC clone in Bolivia (sequence type-423/SNPbol) was found to persist over multiple years and was associated with severe diarrhoea but these strains were variable with respect to antimicrobial resistance patterns. Conclusion/Significance The results showed that although the LT/CS17 phenotype is common among ETEC strains in Bolivia, multiple clones, as determined by unique MLST sequence types, populate this phenotype. Our data also appear to suggest that acquisition and loss of antimicrobial resistance in LT-expressing CS17 ETEC clones is more dynamic than acquisition or loss of virulence factors. PMID:22140423

  1. Unexpected Modulation of Recall B and T Cell Responses after Immunization with Rotavirus-like Particles in the Presence of LT-R192G

    Directory of Open Access Journals (Sweden)

    Christelle Basset

    2010-08-01

    Full Text Available LT-R192G, a mutant of the thermolabile enterotoxin of E. coli, is a potent adjuvant of immunization. Immune responses are generally analyzed at the end of protocols including at least 2 administrations, but rarely after a prime. To investigate this point, we compared B and T cell responses in mice after one and two intrarectal immunizations with 2/6 rotavirus-like particles (2/6-VLP and LT-R192G. After a boost, we found, an unexpected lower B cell expansion measured by flow cytometry, despite a secondary antibody response. We then analyzed CD4+CD25+Foxp3+ regulatory T cells (Tregs and CD4+CD25+Foxp3− helper T cells after in vitro (restimulation of mesenteric lymph node cells with the antigen (2/6-VLP, the adjuvant (LT-R192G or both. 2/6-VLP did not activate CD4+CD25+Foxp3− nor Foxp3+ T cells from non-immunized and 2/6-VLP immunized mice, whereas they did activate both subsets from mice immunized with 2/6-VLP in the presence of adjuvant. LT-R192G dramatically decreased CD4+CD25+Foxp3+ T cells from non-immunized and 2/6-VLP immunized mice but not from mice immunized with 2/6-VLP and adjuvant. Moreover, in this case, LT-R192G increased Foxp3 expression on CD4+CD25+Foxp3+ cells, suggesting specific Treg activation during the recall. Finally, when both 2/6-VLP and LT-R192G were used for restimulation, LT-R192G clearly suppressed both 2/6-VLP-specific CD4+CD25+Foxp3− and Foxp3+ T cells. All together, these results suggest that LT-R192G exerts different effects on CD4+CD25+Foxp3+ T cells, depending on a first or a second contact. The unexpected immunomodulation observed during the recall should be considered in designing vaccination protocols.

  2. Lower leukotriene C4 levels in bronchoalveolar lavage fluid of asthmatic subjects after 2.5 years of inhaled corticosteroid therapy

    Directory of Open Access Journals (Sweden)

    Y. Oosterhoff

    1995-01-01

    Full Text Available Long-term treatment with inhaled corticosteroids has been shown to result in improvement of symptoms and lung function in subjects with asthma. Arachidonic acid (AA metabolites are thought to play a role in the pathophysiology of asthma. It was assessed whether differences could be found in bronchoalveolar lavage (BAL AA metabolite levels between subjects with asthma who were treated for 2.5 years with inhaled bronchodilators alone or in combination with inhaled corticosteroids. Prostaglandin (PGD2, PGF2α, 6-keto-PGF1α, thromboxane B2, leukotriene (LTC4 and LTB4 levels and cell numbers were assessed in BAL fluid from 22 non-smoking asthmatic subjects. They were participating in a randomized, double-blind multicentre drug trial over a period of 2.5 years. Results of the group treated with inhaled corticosteroids (CS+: beclomethasone 200 μg four times daily were compared with the other group (CS− which was treated with either ipratropium bromide (40 μg four times daily or placebo. BAL LTC4 levels of asthmatic subjects were significantly lower after 2.5 years inhaled corticosteroid therapy (CS+, 9(1–17 pg/ml vs. CS−, 16(6-53 pg/ml; p = 0.01. The same trend was observed for the PGD2 levels. The results suggest that inhaled corticosteroids may exert their beneficial effect on lung function via a mechanism in which inhibition of LTC4 synthesis in the airways is involved.

  3. Effects of Xingbi gel on leukotriene E4 and immunoglobulin E production and nasal eosinophilia in a guinea pig model for allergic rhinitis.

    Science.gov (United States)

    Ai, Si; Zheng, Jian; Chu, Ke-Dan; Zhang, Hong-Sheng

    2015-06-01

    Allergic rhinitis (AR) is a chronic inflammatory disease of the nasal airways.Many therapies do not have immediate effects,even which have side-effects.However,the effects of Xingbi gel for the treatment of AR was investigated. We investigated the effects of Xingbi gel on serum levels of leukotriene E4 (LTE4) and immunoglobulin E (IgE), as well as eosinophil counts in the nasal mucosa using a guinea pig model of allergic rhinitis (AR). In addition to a healthy control group without AR, guinea pigs with AR were randomly divided into untreated AR control group, low-dose Xingbi gel (0.2483 g/mL) group, high-dose Xingbi gel (0.4966 g/mL) group, and budesonide group. Compared to the healthy controls, untreated AR guinea pigs had significantly higher ethology scores, serum LTE4 and IgE levels, and nasal mucosa eosinophil counts (p guinea pigs (p production and reducing eosinophilia in the nasal mucosa.

  4. Specially designed B4C/SnO2 nanocomposite for photocatalysis: traditional ceramic with unique properties

    Science.gov (United States)

    Singh, Paviter; Kaur, Gurpreet; Singh, Kulwinder; Singh, Bikramjeet; Kaur, Manpreet; Kaur, Manjot; Krishnan, Unni; Kumar, Manjeet; Bala, Rajni; Kumar, Akshay

    2018-02-01

    Boron carbide: A traditional ceramic material shows unique properties when explored in nano-range. Specially designed boron-based nanocomposite has been synthesized by reflux method. The addition of SnO2 in base matrix increases the defect states in boron carbide and shows unique catalytic properties. The calculated texture coefficient and Nelson-Riley factor show that the synthesized nanocomposite has large number of defect states. Also this composite is explored for the first time for catalysis degradation of industrial used dyes. The degradation analysis of industrial pollutants such as Novacron red Huntsman (NRH) and methylene blue (MB) dye reveals that the composite is an efficient catalyst. Degradation study shows that 1 g/L catalyst concentration of B4C/SnO2 degrades NRH and MB dye up to approximately 97.38 and 79.41%, respectively, in 20 min under sunlight irradiation. This water-insoluble catalyst can be recovered and reused.

  5. Discovery of new erbB4 inhibitors: Repositioning an orphan chemical library by inverse virtual screening.

    Science.gov (United States)

    Giordano, Assunta; Forte, Giovanni; Massimo, Luigia; Riccio, Raffaele; Bifulco, Giuseppe; Di Micco, Simone

    2018-04-12

    Inverse Virtual Screening (IVS) is a docking based approach aimed to the evaluation of the virtual ability of a single compound to interact with a library of proteins. For the first time, we applied this methodology to a library of synthetic compounds, which proved to be inactive towards the target they were initially designed for. Trifluoromethyl-benzenesulfonamides 3-21 were repositioned by means of IVS identifying new lead compounds (14-16, 19 and 20) for the inhibition of erbB4 in the low micromolar range. Among these, compound 20 exhibited an interesting value of IC 50 on MCF7 cell lines, thus validating IVS in lead repurposing. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

  6. Study of coexistence of ferromagnetism and superconductivity in single-crystal ErRh4B4

    International Nuclear Information System (INIS)

    Sinha, S.K.; Crabtree, G.W.; Hinks, D.G.; Mook, H.

    1981-01-01

    Neutron diffraction and resistivity measurements on single crystals of ErRh 4 B 4 have revealed that both superconductivity and ferromagnetic order coexist in this material between 0.71 and 1.2 0 K. In this intermediate phase, a linear polarized modulated structure with a wavelength of approximately 100 A is observed. The modulated moment increases faster than the ferromagnetic moment down to 0.71 K and then disappears suddenly, with loss of superconductivity and a transition to a normal ferromagnetic state. This transition is accompanied by temperature hysteresis of about 60 mK. The same hysteresis, in the inverse sense, is exhibited by the ferromagnetic component. We interpret the intermediate phase as being one of coexisting normal ferromagnetic domains and superconducting sinusoidally ordered domains. Evidence of a small percentage of small ferromagnetic regions of size approx. 100 A is also seen in both the intermediate and ferromagnetic phases. 3 figures

  7. Reactivity and neutron flux measurements in IPEN/MB-01 reactor with B4C burnable poison

    International Nuclear Information System (INIS)

    Fer, Nelson Custodio; Moreira, Joao Manoel Losada

    2000-01-01

    Burnable poison rods, made of B 4 C- Al 2 O 3 pellets with 5.01 mg/cm 3 10 B concentration, have been manufactured for a set of experiments in the IPEN/MB-01 zero-power reactor. Several core parameters which are affected by the burnable poisons rods have been measured. The principal results, for the situation in which the burnable poison rods are located near the absorber rods of a control rod, are they cause a 29% rod worth shadowing, a reduction of 39% in the local void coefficient of reactivity, a reduction of 4.8% in the isothermal temperature coefficient of reactivity, and a reduction of 9% in the thermal neutron flux in the region where the burnable poison rods are located. These experimental results will be used for the validation of burnable poison calculation methods in the CTMSP. (author)

  8. Computational alloy design of (Co1-xNix)88Zr7B4Cu1 nanocomposite soft magnets

    Science.gov (United States)

    Dong, B.; Healy, J.; Lan, S.; Daniil, M.; Willard, M. A.

    2018-05-01

    The dependence of coercivity on composition is an important factor for establishing optimized soft magnetic properties. In this study, we have used the random anisotropy and coherent rotation models to estimate the variation of coercivity with composition in (Co1-xNix)88Zr7B4Cu1 nanocomposite alloys. Our calculations that the magnetoelastic anisotropy contribution to coercivity dominates for Ni rich compositions (x > 0.5). A small range of compositions (0.65 < x < 0.75) is predicted to result in low values of coercivity (<10 A/m). To validate this prediction, (Co1-xNix)88Zr7B4Cu1 nanocomposites in this range were prepared by melt spinning followed by 3600 s isothermal annealing at the primary crystallization peak temperature (˜673 K). Hysteresis loops were measured using vibrating sample magnetometry at room temperature and saturation magnetostriction was measured using a strain gage based magnetostrictometer. Moderately small coercivities (30-40 A/m) and magnetostrictions (3-4 ppm) were measured at for samples with 0.685 < x < 0.725. Our measured coercivity had a minimum value of 32 A/m at x = 0.725, a shift in composition of about 5 at% in the direction of higher Ni content and without the anticipated low value of coercivity. Several reasons for the inaccuracy of this approach are described, including: ignored contributions from amorphous phase (especially in magnetoealstic anisotropy), composition segregation during crystallization leading to unpredictable compositional shifts in prediction, and the general observation that the predictability of minimum coercivity from minimal combined anisotropies has unexplained deviation even in far less complicated materials.

  9. Molecular integration of HoxB4 and STAT3 for self-renewal of hematopoietic stem cells: a model of molecular convergence for stemness.

    Science.gov (United States)

    Hong, Sung-Hyun; Yang, Seung-Jip; Kim, Tae-Min; Shim, Jae-Seung; Lee, Ho-Sun; Lee, Ga-Young; Park, Bo-Bae; Nam, Suk Woo; Ryoo, Zae Young; Oh, Il-Hoan

    2014-05-01

    The upregulation of HoxB4 promotes self-renewal of hematopoietic stem cells (HSCs) without overriding the normal stem cell pool size. A similar enhancement of HSC self-renewal occurs when signal transducer and activator of transcription 3 (STAT3) is activated in HSCs. In this study, to gain insight into the functional organization of individual transcription factors (TFs) that have similar effects on HSCs, we investigated the molecular interplay between HoxB4 and STAT3 in the regulation of HSC self-renewal. We found that while STAT3-C or HoxB4 similarly enhanced the in vitro self-renewal and in vivo repopulating activities of HSCs, simultaneous transduction of both TFs did not have additive effects, indicating their functional redundancy in HSCs. In addition, activation of STAT3 did not cause changes in the expression levels of HoxB4. In contrast, the inhibition of STAT3 activity in HoxB4-overexpressing hematopoietic cells significantly abrogated the enhancing effects of HoxB4, and the upregulation of HoxB4 caused a ligand-independent Tyr-phosphorylation of STAT3. Microarray analysis revealed a significant overlap of the transcriptomes regulated by STAT3 and HoxB4 in undifferentiated hematopoietic cells. Moreover, a gene set enrichment analysis showed significant overlap in the candidate TFs that can recapitulate the transcriptional changes induced by HoxB4 or STAT3. Interestingly, among these common TFs were the pluripotency-related genes Oct-4 and Nanog. These results indicate that tissue-specific TFs regulating HSC self-renewal are functionally organized to play an equivalent role in transcription and provide insights into the functional convergence of multiple entries of TFs toward a conserved transcription program for the stem cell state. © 2014 AlphaMed Press.

  10. High performance ceria-bismuth bilayer electrolyte low temperature solid oxide fuel cells (LT-SOFCs) fabricated by combining co-pressing with drop-coating

    KAUST Repository

    Hou, Jie; Bi, Lei; Qian, Jing; Zhu, Zhiwen; Zhang, Junyu; Liu, Wei

    2015-01-01

    The Sm0.075Nd0.075Ce0.85O2-δ-Er0.4Bi1.6O3 bilayer structure film, which showed an encouraging performance in LT-SOFCs, was successfully fabricated by a simple low cost technique combining one-step co-pressing with drop-coating.

  11. High performance ceria-bismuth bilayer electrolyte low temperature solid oxide fuel cells (LT-SOFCs) fabricated by combining co-pressing with drop-coating

    KAUST Repository

    Hou, Jie

    2015-03-24

    The Sm0.075Nd0.075Ce0.85O2-δ-Er0.4Bi1.6O3 bilayer structure film, which showed an encouraging performance in LT-SOFCs, was successfully fabricated by a simple low cost technique combining one-step co-pressing with drop-coating.

  12. Effects of doping on ferroelectric properties and leakage current behavior of KNN-LT-LS thin films on SrTiO3 substrate

    Science.gov (United States)

    Abazari, M.; Safari, A.

    2009-05-01

    We report the effects of Ba, Ti, and Mn dopants on ferroelectric polarization and leakage current of (K0.44Na0.52Li0.04)(Nb0.84Ta0.1Sb0.06)O3 (KNN-LT-LS) thin films deposited by pulsed laser deposition. It is shown that donor dopants such as Ba2+, which increased the resistivity in bulk KNN-LT-LS, had an opposite effect in the thin film. Ti4+ as an acceptor B-site dopant reduces the leakage current by an order of magnitude, while the polarization values showed a slight degradation. Mn4+, however, was found to effectively suppress the leakage current by over two orders of magnitude while enhancing the polarization, with 15 and 23 μC/cm2 remanent and saturated polarization, whose values are ˜70% and 82% of the reported values for bulk composition. This phenomenon has been associated with the dual effect of Mn4+ in KNN-LT-LS thin film, by substituting both A- and B-site cations. A detailed description on how each dopant affects the concentrations of vacancies in the lattice is presented. Mn-doped KNN-LT-LS thin films are shown to be a promising candidate for lead-free thin films and applications.

  13. Resuscitation of the viable but non-culturable state of Salmonella enterica serovar Oranienburg by recombinant resuscitation-promoting factor derived from Salmonella Typhimurium strain LT2.

    Science.gov (United States)

    Panutdaporn, N; Kawamoto, K; Asakura, H; Makino, S-I

    2006-02-15

    A gene encoding the resuscitation-promoting factor (Rpf) from Salmonella Typhimurium LT2 was cloned and characterized. The amino acid sequence encoded by S. Typhimurium LT2 rpf gene shares 24.2% homology with Micrococcus luteus Rpf, which is secreted by growing cells, and required to resuscitate from viable but non-culturable (VNC) state. The S. Typhimurium LT2 rpf gene is 696 bp long, and shared a conserved segment with Salmonella enterica serovar Oranienburg (99.4%). Recombinant Rpf (rRpf) proteins of S. Typhimurium LT2 after expression in E. coli BL21 harboring the pET15-b plasmid was approximately 25 kDa. Since S. Oranienburg cells are relatively quick to enter the VNC state just after incubating in the presence of 7% NaCl at 37 degrees C for 3 days, we evaluated the biological effect of rRpf by using S. Oranienburg VNC cells. The rRpf not only promoted proliferation but also induced resuscitation of VNC cells to the culturable state in a dose-dependent manner. Therefore, rRpf may be useful for detection of bacterial contaminants present in the VNC form in food samples and the environment.

  14. VizieR Online Data Catalog: L/T transition dwarfs search with PS1 & WISE. II. (Best+, 2015)

    Science.gov (United States)

    Best, W. M. J.; Liu, M. C.; Magnier, E. A.; Deacon, N. R.; Aller, K. M.; Redstone, J.; Burgett, W. S.; Chambers, K. C.; Draper, P.; Flewelling, H.; Hodapp, K. W.; Kaiser, N.; Metcalfe, N.; Tonry, J. L.; Wainscoat, R. J.; Waters, C.

    2016-03-01

    We used the new Pan-STARRS1 Survey (PS1; Kaiser et al. 2010SPIE.7733E..0EK) detections through 2012 January cross-matched with the Wide-field Infrared Survey Explorer (WISE; Wright et al. 2010AJ....140.1868W) All-sky Release using a 3" matching radius. In Best et al. (2013ApJ...777...84B; Paper I), we presented seven initial discoveries from our search, all bright L/T transition dwarfs within 15pc. In this paper, we present the complete results of our search, including 79 total L/T transition dwarfs and 23 young or potentially young late-M and L dwarfs. The PS1 3π survey (K. C. Chambers et al. 2016AAS...22732407C) has obtained an average of ~12 epochs of imaging in five optical bands (gP1, rP1, iP1, zP1, yP1) with a 1.8-m wide-field telescope on Haleakala, Maui, covering the entire sky north of -30° declination. Imaging began in 2010 May and concluded in 2014 March. The WISE All-sky Source Catalog (Cutri et al. 2012, II/311) comprises data taken between 2010 January and August in four mid-infrared bands: W1 (3.6um), W2 (4.5um), W3 (12um), and W4 (22um). We searched the UKIDSS Data Release 9 (DR9; Lawrence et al. 2013, II/319) and VISTA Hemisphere Survey (Cross et al. 2012A&A...548A.119C) catalogs for JHK photometry of our candidates on the Mauna Kea Observatories (MKO) filter system. For objects not found in either survey, we obtained follow-up images using WFCAM on the 3.8m United Kingdom InfraRed Telescope (UKIRT) as part of the UKIRT Service Program. Observations took place on multiple nights spanning 2010 September to 2013 December. We obtained low-resolution near-IR spectra for our 142 candidates between 2012 July and 2014 January using the NASA IRTF/SpeX spectrograph (details of our observations are listed in table 3). (7 data files).

  15. Fully-human Monoclonal Antibodies Against Human EphrinB2 and EphB4 | NCI Technology Transfer Center | TTC

    Science.gov (United States)

    The National Cancer Institute's Cancer and Inflammation Program is seeking statements of capability or interest from parties interested in licensing fully-human monoclonal antibodies against human EphrinB2 and EphB4.

  16. 17 CFR 240.3b-4 - Definition of “foreign government,” “foreign issuer” and “foreign private issuer”.

    Science.gov (United States)

    2010-04-01

    ... government,â âforeign issuerâ and âforeign private issuerâ. 240.3b-4 Section 240.3b-4 Commodity and... Definition of “foreign government,” “foreign issuer” and “foreign private issuer”. (a) The term foreign... country. (c) The term foreign private issuer means any foreign issuer other than a foreign government...

  17. Laser induced fluorescence of TiD: analysis of the B4Γ-X4Φ transition

    International Nuclear Information System (INIS)

    Danielsson, M

    2007-01-01

    A titanium hollow cathode lamp in combination with a dye laser and a monochromator has been used to resolve the laser-induced fluorescence of the TiD molecule. This has enabled the extension of the earlier rotational analysis of the (0,0) band of the B 4 Γ-X 4 Φ transition. In addition, the (1,1) band and part of the (2,2) band have been observed and analyzed. All earlier works on the TiD and TiH molecules concern the (0,0) band. The present work is the first to report experimentally determined equilibrium constants for TiD. For the ground state X 4 Φ the principal parameters are (in cm -1 ) A e =33.075, B e =2.7804, D e =6.819x10 -5 and α e =0.0466. By using the isotope relationships the corresponding equilibrium parameters for the TiH molecule are given

  18. First-principles investigation of neutron-irradiation-induced point defects in B4C, a neutron absorber for sodium-cooled fast nuclear reactors

    Science.gov (United States)

    You, Yan; Yoshida, Katsumi; Yano, Toyohiko

    2018-05-01

    Boron carbide (B4C) is a leading candidate neutron absorber material for sodium-cooled fast nuclear reactors owing to its excellent neutron-capture capability. The formation and migration energies of the neutron-irradiation-induced defects, including vacancies, neutron-capture reaction products, and knocked-out atoms were studied by density functional theory calculations. The vacancy-type defects tend to migrate to the C–B–C chains of B4C, which indicates that the icosahedral cage structures of B4C have strong resistance to neutron irradiation. We found that lithium and helium atoms had significantly lower migration barriers along the rhombohedral (111) plane of B4C than perpendicular to this plane. This implies that the helium and lithium interstitials tended to follow a two-dimensional diffusion regime in B4C at low temperatures which explains the formation of flat disk like helium bubbles experimentally observed in B4C pellets after neutron irradiation. The knocked-out atoms are considered to be annihilated by the recombination of the close pairs of self-interstitials and vacancies.

  19. Hippocampal changes produced by overexpression of the human CHRNA5/A3/B4 gene cluster may underlie cognitive deficits rescued by nicotine in transgenic mice.

    Science.gov (United States)

    Molas, Susanna; Gener, Thomas; Güell, Jofre; Martín, Mairena; Ballesteros-Yáñez, Inmaculada; Sanchez-Vives, Maria V; Dierssen, Mara

    2014-11-11

    Addiction involves long-lasting maladaptive changes including development of disruptive drug-stimuli associations. Nicotine-induced neuroplasticity underlies the development of tobacco addiction but also, in regions such as the hippocampus, the ability of this drug to enhance cognitive capabilities. Here, we propose that the genetic locus of susceptibility to nicotine addiction, the CHRNA5/A3/B4 gene cluster, encoding the α5, α3 and β4 subunits of the nicotinic acetylcholine receptors (nAChRs), may influence nicotine-induced neuroadaptations. We have used transgenic mice overexpressing the human cluster (TgCHRNA5/A3/B4) to investigate hippocampal structure and function in genetically susceptible individuals. TgCHRNA5/A3/B4 mice presented a marked reduction in the dendrite complexity of CA1 hippocampal pyramidal neurons along with an increased dendritic spine density. In addition, TgCHRNA5/A3/B4 exhibited increased VGLUT1/VGAT ratio in the CA1 region, suggesting an excitatory/inhibitory imbalance. These hippocampal alterations were accompanied by a significant impairment in short-term novelty recognition memory. Interestingly, chronic infusion of nicotine (3.25 mg/kg/d for 7 d) was able to rescue the reduced dendritic complexity, the excitatory/inhibitory imbalance and the cognitive impairment in TgCHRNA5/A3/B4. Our results suggest that chronic nicotine treatment may represent a compensatory strategy in individuals with altered expression of the CHRNA5/A3/B4 region.

  20. Characterization of Carbon-Contaminated B4C-Coated Optics after Chemically Selective Cleaning with Low-Pressure RF Plasma.

    Science.gov (United States)

    Moreno Fernández, H; Rogler, D; Sauthier, G; Thomasset, M; Dietsch, R; Carlino, V; Pellegrin, E

    2018-01-22

    Boron carbide (B 4 C) is one of the few materials that is expected to be most resilient with respect to the extremely high brilliance of the photon beam generated by free electron lasers (FELs) and is thus of considerable interest for optical applications in this field. However, as in the case of many other optics operated at light source facilities, B 4 C-coated optics are subject to ubiquitous carbon contaminations. Carbon contaminations represent a serious issue for the operation of FEL beamlines due to severe reduction of photon flux, beam coherence, creation of destructive interference, and scattering losses. A variety of B 4 C cleaning technologies were developed at different laboratories with varying success. We present a study regarding the low-pressure RF plasma cleaning of carbon contaminated B 4 C test samples via inductively coupled O 2 /Ar, H 2 /Ar, and pure O 2 RF plasma produced following previous studies using the same ibss GV10x downstream plasma source. Results regarding the chemistry, morphology as well as other aspects of the B 4 C optical coating before and after the plasma cleaning are reported. We conclude that among the above plasma processes only plasma based on pure O 2 feedstock gas exhibits the required chemical selectivity for maintaining the integrity of the B 4 C optical coatings.

  1. Tectonic origin of serpentinites on Syros, Greece: Geochemical signatures of abyssal origin preserved in a HP/LT subduction complex

    Science.gov (United States)

    Cooperdock, Emily H. G.; Raia, Natalie H.; Barnes, Jaime D.; Stockli, Daniel F.; Schwarzenbach, Esther M.

    2018-01-01

    This study combines whole rock trace and major element geochemistry, and stable isotope (δD and δ18O) analyses with petrographic observations to deduce the origin and tectonic setting of serpentinization of ultramafic blocks from the exhumed HP/LT Aegean subduction complex on Syros, Greece. Samples are completely serpentinized and are characterized by mineral assemblages that consist of variable amounts of serpentine, talc, chlorite, and magnetite. δD and δ18O values of bulk rock serpentinite powders and chips (δD = - 64 to - 33‰ and δ18O = + 5.2 to + 9.0‰) reflect hydration by seawater at temperatures serpentinization by seawater, followed by secondary fluid-rock interactions with a sedimentary source pre- or syn-subduction. Whole rock major element, trace element, and REE analyses record limited melt extraction, exhibit flat REE patterns, and do not show pronounced Eu anomalies. The geochemical signatures preserved in these serpentinites argue against a mantle wedge source, as has been previously speculated for ultramafic rocks on Syros. Rather, the data are consistent with derivation from abyssal peridotites in a hyper-extended margin setting or mid-ocean ridge and fracture zone environment. In either case, the data suggest an extensional and/or oceanic origin associated with the Cretaceous opening of the Pindos Ocean and not a subduction-related derivation from the mantle wedge.

  2. Captain Nemo/Lt-General Pitt Rivers and Cleopatra’s Needle — A Story of Flagships

    Directory of Open Access Journals (Sweden)

    Christopher Evans

    2005-11-01

    Full Text Available Recently re-reading Verne’s 20,000 Leagues Beneath the Sea for our children I was struck by the marked similarities between the novel’s elusive protagonist, Captain Nemo, and the renowned later 19th century British archaeologist, Lt.-General Pitt Rivers. Could they have been the same person? How could something so seemingly blatant have gone unnoticed? These questions are, of course, only raised in a spirit of academic tongue-in-check. Yet, in an ethos of ‘learning through amusement’ (itself directly relevant to the themes of this study, exploring the parallels between these two ‘heroic’ individuals provides insights into the nature of 19th century science, Victorian edification and disciplinary institutionalisation (e.g. Levine 1986. This eclectic contribution will, moreover, be introduced with the third component of its headline title – Cleopatra’s Needle – as this provides an appropriately quasinautical parable on the project of 19th century archaeology and the problem of ‘deep time’ (Murray 1993.

  3. MAC-1 Glycoprotein Family mediates adherence of neutrophils to endothelial cells stimulated by leukotriene B/sub 4/ and platelet activating factor

    Energy Technology Data Exchange (ETDEWEB)

    Tonnesen, M.G.; Anderson, D.C.; Springer, T.A.; Knedler, A.; Avdi, N.; Henson, P.M.

    1986-03-01

    The process of neutrophil (N) adhesion to and migration through endothelium (EC), an early event in the induction of the acute inflammatory response, has been attributed to the generation of extravascular chemoattractant peptides and lipids. Although both leukotriene B/sub 4/ (LTB/sub 4/) and platelet activating factor (PAF) enhance N adherence to EC, the mechanisms involved in this interaction are still not completely understood. Since the MAC-1 Glycoprotein (GP) Family has recently been shown to be required for a variety of adherence-dependent functions of stimulated N, the authors questioned whether these adherence-associated GP might be involved in N adherence to EC stimulated by LTB/sub 4/ or PAF. Using a microtiter adherence assay with /sup 111/In labeled N, they assessed the ability of N from patients with MAC-1, LFA-1 Deficiency to adhere to monolayers of human omental microvascular or umbilical vein EC as well as to serum-coated plastic. Patient N exhibited markedly diminished adherence in response to LTB/sub 4/ or PAF compared to normal controls. LTB/sub 4/ and PAF enhanced expression of the MAC-1 GP Family on the surface of normal N as determined by flow cytofluorimetry using a monoclonal antibody (TS1/18) to the GP common beta subunit. In addition TS1/18 (20 ..mu..g/ml) completely inhibited N adherence stimulated by either LTB/sub 4/ (10/sup -8/M) or PAF(10/sup -11/M). Thus, the MAC-1 GP Family appears to be important in chemotactic factor regulation of N adherence to EC.

  4. Lt Richard Gueli

    African Journals Online (AJOL)

    Win98SE

    reality, conflicts in Africa (and other parts of the world), often fuelled by deep- ... Often, confusion exists between what is meant by human rights law and .... assist peoples in their right to self-determination; as a result of a state formally consenting ...... As regional 'superpower', it could be argued that South Africa should take a.

  5. Salivary anti-coxsackievirus-B4 neutralizing activity and pattern of immune parameters in patients with type 1 diabetes: a pilot study.

    Science.gov (United States)

    Nekoua, Magloire Pandoua; Yessoufou, Akadiri; Alidjinou, Enagnon Kazali; Badia-Boungou, Francis; Moutairou, Kabirou; Sane, Famara; Hober, Didier

    2018-05-17

    Enteroviruses, especially coxsackieviruses B (CV-B), have been associated with the pathogenesis of type 1 diabetes (T1D). An anti-CV-B4 neutralizing activity in saliva of T1D patients was previously reported. Our aim was to study the association between the saliva anti-CV-B4 neutralizing activity and immune parameters in T1D patients in comparison with non-diabetic individuals. Saliva and blood samples were collected from 15 T1D patients and 8 controls. The anti-CV-B4 and anti-poliovirus type 1 (PV-1) activities of saliva and serum samples were determined by a plaque neutralization assay. Quantification of serum cytokines was performed by ELISA and the frequencies of lymphocyte subsets were evaluated using flow cytometry. The levels of salivary anti-CV-B4 neutralizing activity were higher in T1D patients than in controls (p = 0.02), whereas the serum levels of anti-CV-B4 neutralizing activity and the saliva and serum levels of anti-PV-1 neutralizing activity were not different. The proportions of effector CD4 + T cells and CD19 + B cells, but not those of CD4 + T cells, CD8 + T cells and Foxp3 + regulatory T cells, were higher in T1D patients than in controls (p = 0.02 and p = 0.01 respectively). Moreover, serum IFN-γ levels were lower in T1D patients compared to controls (p = 0.03) while IL-4 and IL-10 were not different. There was an association between saliva anti-CV-B4 activity, down-regulation of IFN-γ and B cell expansion in peripheral blood of T1D patients. The association between saliva anti-CV-B4 activity and disturbance of immune system in T1D patients deserves further investigation.

  6. HTLV-1 specific CD8+ T cell function augmented by blockade of 2B4/CD48 interaction in HTLV-1 infection.

    Directory of Open Access Journals (Sweden)

    Chibueze Chioma Ezinne

    Full Text Available CD8+ T cell response is important in the response to viral infections; this response though is regulated by inhibitory receptors. Expression of inhibitory receptors has been positively correlated with CD8+ T cell exhaustion; the consequent effect of simultaneous blockade of these inhibitory receptors on CD8+ T cell response in viral infections have been studied, however, the role of individual blockade of receptor-ligand pair is unclear. 2B4/CD48 interaction is involved in CD8+T cell regulation, its signal transducer SAP (signaling lymphocyte activation molecule (SLAM-associated protein is required for stimulatory function of 2B4/CD244 on lymphocytes hence, we analyzed 2B4/CD244 (natural killer cell receptor and SAP (signaling lymphocyte activation molecule(SLAM-associated protein on total CD8+ and HTLV-1 specific CD8+T cells in HTLV-1 infection and the effect of blockade of interaction with ligand CD48 on HTLV-1 specific CD8+ T cell function. We observed a high expression of 2B4/CD244 on CD8+ T cells relative to uninfected and further upregulation on HTLV-1 specific CD8+ T cells. 2B4+ CD8+ T cells exhibited more of an effector and terminally differentiated memory phenotype. Blockade of 2B4/CD48 interaction resulted in improvement in function via perforin expression and degranulation as measured by CD107a surface mobilization on HTLV-1 specific CD8+ T cells. In the light of these findings, we thus propose an inhibitory role for 2B4/CD48 interaction on CD8+T cell function.

  7. Yoğurt Yapımında Saf Kültürün Kullanımı

    Directory of Open Access Journals (Sweden)

    Sevda Kılıç

    2015-02-01

    Full Text Available Yoğurt, sütün L. bulgaricus ve S. thermophilus bakterilerini belirli oranlarda içeren kültürle aşılanması sonucu elde edilen bir süt mamülüdür. Yoğurt teknolojisinde yaklaşık 70 yıldır kültür kullanılmaktadır. Kültürün hazırlanmasında yararlanılan bakteriler, belirli özellikleri dikkate alınarak seçilmektedir. Daha sonra yağsız süt tozundan hazırlanan süte aşılanarak 42-44 oC’de inkübasyona bırakılmakta ve pH 4.7 olduğunda inkübasyona son verilerek çoğaltımı ve aktifleşmeleri sağlanmaktadır. Günümüzde diğer ülkelerde olduğu gibi ülkemizde de kültür kullanımı gıda maddeleri tüzüğünün 51. maddesine göre zorunlu tutulmaktadır. Ancak buna rağmen kültür, tam anlamıyla bilinmemekte veya bilinçli olarak kullanılmamaktadır. Yoğurt teknolojisinde kültür, kullanımı ile daha kaliteli yoğurt yapılmaktadır. Uzun süre tat, aroma ve yapısı bozulmadan saklanabilmekte, raf ömrü uzamaktadır. Normal sertlikte olan yoğurtta asitlik istenilen düzeyde olduğu için su salmada görülmez.

  8. Comparison of “Morning Olifera Seed Extract and Magnafloc LT25” in Removal of Water Turbidity Case Study: Tehran’s Jalalieh (1 Water Treatment Plant

    Directory of Open Access Journals (Sweden)

    Mehdi Khan ahmadi

    2013-08-01

    Full Text Available Coagulation-flocculation is one of the most important processes for water treatment, commonly used all over the world. The use of synthetic polymers known as “Polyelectrolytes as a coagulant aid is now wide spread in water treatment plants. Tehran’s “Jalalieh WTP” has been using an anionic polyelectrolyte under the trade name of “Magna Floc LT25” for a number of years MagnaFloc LT25 (MF-LT25 is a synthetic coagulant with high molecular weight, produced in granular and powder form. The application of this coagulant aid is known to be most effective if injected to water after addition of main coagulant (Ferric Chloride in Tehran’s WTP.  However the use of synthetic polymers in treatment of drinking water has always been under question due to extract of MO seed contains proteins soluble in water which have high coagulating properties. This pilot scale study was performed to compare the coagulating properties of seed extract of MO to MF-LT25, The tests were carried out on Tehran’s raw water in Jalalieh treatment plant. Several turbidity ranges such as 5, 20, 100, and 200 NTU were used representing real seasonal turbidities of influent water to treatment plant. Optimum concentration of the coagulant and coagulant aid was determined within water pH values of 6, 7 and 8, using common “Jar Test” technique. The extract of Moringa Oleifera seed in optimum concentration of 10, 14,25,35 mg/L and optimum pH of 8 is capable in removal of 96.5, 97.4, 98.5 and 99% of water turbidity range of 5, 20, 100, and 200 NTU respectively. Under similar conditions, MF-LT25 removal efficiency were found 97, 98.1, 98.4 and 99.4% of water turbidity range of 5, 20, 100, and 200 NTU at optimum concentrations of 0.015, 0.02, 0.025, 0.03 mg/L respectively. The results also showed that the extract of Moringa Oleifera seed is a powerful coagulating agent, at alkalinity pH values, and is more effective for high turbid waters. It compared well with synthetic

  9. Development and preclinical evaluation of safety and immunogenicity of an oral ETEC vaccine containing inactivated E. coli bacteria overexpressing colonization factors CFA/I, CS3, CS5 and CS6 combined with a hybrid LT/CT B subunit antigen, administered alone and together with dmLT adjuvant.

    Science.gov (United States)

    Holmgren, J; Bourgeois, L; Carlin, N; Clements, J; Gustafsson, B; Lundgren, A; Nygren, E; Tobias, J; Walker, R; Svennerholm, A-M

    2013-05-07

    A first-generation oral inactivated whole-cell enterotoxigenic Escherichia coli (ETEC) vaccine, comprising formalin-killed ETEC bacteria expressing different colonization factor (CF) antigens combined with cholera toxin B subunit (CTB), when tested in phase III studies did not significantly reduce overall (generally mild) ETEC diarrhea in travelers or children although it reduced more severe ETEC diarrhea in travelers by almost 80%. We have now developed a novel more immunogenic ETEC vaccine based on recombinant non-toxigenic E. coli strains engineered to express increased amounts of CF antigens, including CS6 as well as an ETEC-based B subunit protein (LCTBA), and the optional combination with a nontoxic double-mutant heat-labile toxin (LT) molecule (dmLT) as an adjuvant. Two test vaccines were prepared under GMP: (1) A prototype E. coli CFA/I-only formalin-killed whole-cell+LCTBA vaccine, and (2) A "complete" inactivated multivalent ETEC-CF (CFA/I, CS3, CS5 and CS6 antigens) whole-cell+LCTBA vaccine. These vaccines, when given intragastrically alone or together with dmLT in mice, were well tolerated and induced strong intestinal-mucosal IgA antibody responses as well as serum IgG and IgA responses to each of the vaccine CF antigens as well as to LT B subunit (LTB). Both mucosal and serum responses were further enhanced (adjuvanted) when the vaccines were co-administered with dmLT. We conclude that the new multivalent oral ETEC vaccine, both alone and especially in combination with the dmLT adjuvant, shows great promise for further testing in humans. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. Astrobiology Training in Lava Tubes (ATiLT): Characterizing coralloid speleothems in basaltic lava tubes as a Mars analogue

    Science.gov (United States)

    Ni, J.; Leveille, R. J.; Douglas, P.

    2017-12-01

    Coralloid speleothems or cave corals are small mineralised nodes that can take a variety of forms, and which develop through groundwater seepage and water-rock interaction in caves. They are found commonly on Earth in a plethora of caves, including lava tubes. Since lava tubes have been identified on the surface of Mars from remotely sensed images, there has been interest in studying Earth's lava tube systems as an analogue for understanding Martian lava environments. If cave minerals were found on Mars, they could indicate past or present water-rock interaction in the Martian subsurface. Martian lava tubes could also provide insights into habitable subsurface environments as well as conditions favourable for the synthesis and preservation of biosignatures. One of the aims of the Astrobiology Training in Lava Tubes (ATiLT) project is to analyze biosignatures and paleoenvironmental indicators in secondary cave minerals, which will be looked at in-situ and compared to collected field samples. In this study, secondary mineralization in lava cave systems from Lava Beds National Monument, CA is examined. In the field, coralloid speleothems have been observed growing on all surfaces of the caves, including cave ceilings, floors, walls and overhangs. They are also observed growing adjacent to biofilms, which sometimes fill in the cracks of the coralloid nodes. Preliminary results show the presence of opal, calcite, quartz and other minor minerals in the speleothems. This study seeks to understand the formation mechanism and source of these secondary minerals, as well as determine their possible relation to the biofilms. This will be done through the analysis of the water chemistry, isotope geochemistry and microscale mineralogy.

  11. Squamous Cell Carcinoma Antigen-encoding Genes SERPINB3/B4 as Potentially Useful Markers for the Stratification of HNSCC Tumours.

    Science.gov (United States)

    Saidak, Zuzana; Morisse, Mony Chenda; Chatelain, Denis; Sauzay, Chloé; Houessinon, Aline; Guilain, Nelly; Soyez, Marion; Chauffert, Bruno; Dakpé, Stéphanie; Galmiche, Antoine

    2018-03-01

    The squamous cell carcinoma antigen (SCCA), encoded by the genes SERPINB3/B4, is a tumour marker produced by head and neck squamous cell carcinoma (HNSCC). We aimed to examine SERPINB3/B4 mRNA levels and its clinical significance in the therapeutic context. We retrieved mRNA expression levels, clinical, pathological and genomic data for 520 HNSCC from The Cancer Genome Atlas (TCGA). HNSCC tumours express high levels of SERPINB3/B4 mRNA. SERPINB3 expression differs depending on Human papillomavirus (HPV) infection status, primary tumour location, grade and differentiation, extension to lymph nodes and extracapsular spread. Interestingly, we observed an association between SERPINB3/B4 and the presence of tumour immune infiltrate as well as the expression of the immune checkpoint regulators PD-L1/PD-L2 that depended on HPV status. Our findings point to potential interest of SERPINB3/B4 for the stratification of HNSCC patients in the therapeutic context. Copyright© 2018, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

  12. TiO2 nanosheets decorated with B4C nanoparticles as photocatalysts for solar fuel production under visible light irradiation

    Science.gov (United States)

    Zhang, Xiaojie; Yang, Jipeng; Cai, Tiancong; Zuo, Guoqiang; Tang, Changqing

    2018-06-01

    Boron carbide (B4C) nanoparticles-decorated anatase titanium dioxide (TiO2) nanosheets photocatalysts were synthesized by a hydrothermal method in the presence of hydrofluoric acid and characterized by field emission scanning electron microscope, high-resolution transmission electron microscope, UV-vis diffuse reflectance spectra, photoluminescence spectra, etc. With metallic Pt nanoparticles as a co-catalyst, the as-synthesized B4C/TiO2 composites were evaluated using photocatalytic CO2 or H2O reduction to solar fuels such as methane and hydrogen. Under either simulated sunlight or visible light irradiation, coupling p-type B4C with n-type anatase TiO2 significantly improved the photocatalytic performance. Both photoluminescence and transient photocurrent measurements indicated that the interfacial coupling effect between B4C and anatase TiO2 could significantly promote photo-excited charges separations. On the basis of measurements and literatures, a possible mechanism of excited charges transfer at the B4C-anatase TiO2 heterojunction interface during irradiation was deduced.

  13. Enhancement in the microstructure and neutron shielding efficiency of sandwich type of 6061Al–B4C composite material via hot isostatic pressing

    International Nuclear Information System (INIS)

    Park, Jin-Ju; Hong, Sung-Mo; Lee, Min-Ku; Rhee, Chang-Kyu; Rhee, Won-Hyuk

    2015-01-01

    Highlights: • 6061Al–B 4 C neutron shielding composites are fabricated by sintering and HIP. • HIP process improves the wettability of B 4 C particles into 6061Al matrix. • Neutron attenuation performance can be enhanced by application of HIP process. - Abstract: Sandwich type of 6061Al–B 4 C composite plates, which are used as a thermal neutron absorber for spent nuclear fuel pool storage rack, were fabricated using two different consolidation ways as sintering and hot isostatic pressing (HIP) processes and their thermal neutron shielding efficiency was investigated as a function of B 4 C concentration ranging from 0 to 40 wt.%. For this purpose, two respective inner core compaction parts of sintered and HIPped neutron absorbing composite materials were first produced and then cladded them between two outer plates by HIP process. The application of HIP process provided not only a lead of excellent interfacial adhesion due to the improved wettability but also an enhancement of thermal neutron shielding efficiency owing to the more uniform dispersion of B 4 C particles

  14. Highly active, bi-functional and metal-free B4C-nanoparticle-modified graphite felt electrodes for vanadium redox flow batteries

    Science.gov (United States)

    Jiang, H. R.; Shyy, W.; Wu, M. C.; Wei, L.; Zhao, T. S.

    2017-10-01

    The potential of B4C as a metal-free catalyst for vanadium redox reactions is investigated by first-principles calculations. Results show that the central carbon atom of B4C can act as a highly active reaction site for redox reactions, due primarily to the abundant unpaired electrons around it. The catalytic effect is then verified experimentally by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) tests, both of which demonstrate that B4C nanoparticles can enhance the kinetics for both V2+/V3+ and VO2+/VO2+ redox reactions, indicating a bi-functional effect. The B4C-nanoparticle-modified graphite felt electrodes are finally prepared and tested in vanadium redox flow batteries (VRFBs). It is shown that the batteries with the prepared electrodes exhibit energy efficiencies of 88.9% and 80.0% at the current densities of 80 and 160 mA cm-2, which are 16.6% and 18.8% higher than those with the original graphite felt electrodes. With a further increase in current densities to 240 and 320 mA cm-2, the batteries can still maintain energy efficiencies of 72.0% and 63.8%, respectively. All these results show that the B4C-nanoparticle-modified graphite felt electrode outperforms existing metal-free catalyst modified electrodes, and thus can be promising electrodes for VRFBs.

  15. Table-like magnetocaloric effect of Fe88−xNdxCr8B4 composite materials

    International Nuclear Information System (INIS)

    Lai, J.W.; Zheng, Z.G.; Zhong, X.C.; Franco, V.; Montemayor, R.; Liu, Z.W.; Zeng, D.C.

    2015-01-01

    The narrow working temperature range due to the sharp magnetic entropy change |ΔS M | peak and large thermal or magnetic hysteresis restricts the practical application of magnetocaloric materials. In this work, the table-like magnetocaloric effect (MCE) was obtained in the multilayer composite of Fe 88−x Nd x Cr 8 B 4 alloys with various Nd substitutions for Fe (x=5, 8, 10, 12, and 15), which were prepared by arc-melting followed by melt-spinning. The substation of Nd was found to enhance the glass-forming ability. For the alloys with Nd substitution from 5 at% to 15 at%, the Curie temperature (T C ) ranged from 322 K to 350 K and the peak value of |ΔS M | remained almost constant, 3.4–3.5 J/(kg K) under an applied field of 0–5 T. The composite with various Nd contents was prepared by stocking the ribbons layer by layer. The |ΔS M | of the composite approached a nearly constant value of ∼3.2 J/(kg K) in a field change of 0–5 T in a wide temperature span over 40 K, resulting in large refrigerant capacity value of >408 J/kg. This |ΔS M | value was much larger than the previous reported Fe-based amorphous composite Fe 78−x Ce x Si 4 Nb 5 B 12 Cu 1 . This composite can be used as the working material in the Ericsson-cycle magnetic regenerative refrigerator around room temperature. - Highlights: • The T C ranges from 322 K to 350 K when increasing Nd substitution from 5 to 15 at%. • |ΔS M | remains relatively constant, about 3.4–3.5 J/(kg K) under H=0–5 T. • RC decreases from 93 to 78 J/kg in a field change of 1.5 T when Nd increasing. • Table-like MCE ,|ΔS M | ~3.2J/kg K under 0–5 T, appeared in the composite. • A wide working temperature range (40 K) and enhanced RC (>408J/kg) were obtained in the composite

  16. CONTEMPT-LT/028: a computer program for predicting containment pressure-temperature response to a loss-of-coolant accident

    International Nuclear Information System (INIS)

    Hargroves, D.W.; Metcalfe, L.J.; Wheat, L.L.; Niederauer, G.F.; Obenchain, C.F.

    1979-03-01

    CONTEMPT-LT is a digital computer program, written in FORTRAN IV, developed to describe the long-term behavior of water-cooled nuclear reactor containment systems subjected to postulated loss-of-coolant accident (LOCA) conditions. The program calculates the time variation of compartment pressures, temperatures, mass and energy inventories, heat structure temperature distributions, and energy exchange with adjacent compartments. The program is capable of describing the effects of leakage on containment response. Models are provided to describe fan cooler and cooling spray engineered safety systems. An annular fan model is also provided to model pressure control in the annular region of dual containment systems. Up to four compartments can be modeled with CONTEMPT-LT, and any compartment except the reactor system may have both a liquid pool region and an air--vapor atmosphere region above the pool. Each region is assumed to have a uniform temperature, but the temperatures of the two regions may be different

  17. Effekten af hydraulisk kontrol på den vertikale fordeling og sammensætning af fytoplankton og zooplanktonsamfundene i Lillebælt

    DEFF Research Database (Denmark)

    Nielsen, Erik Haar; Christensen, Jens Tang; Lund-Hansen, Lars Chresten

    Effekten af strømbetinget opblanding på fytoplankton og zooplankton sammensætningen i en lagdelt vandsøjle blev undersøgt i Lillebælt i april 2015. De hydrografiske forhold blev kortlagt gennem kontinuerlige målinger med ADCP og undulerende CTD (Scanfish III) langs et transekt fra Tragten nord...... for Fredericia til det centrale Lillebælt. Vandprøver til analyse af fytoplankton blev taget fra tre strata med CTD forsynet med en rosette med Niskin -vandhentere og zooplankton blev indsamlet med et Multinet-maxi (HydroBios, Kiel) fra 9 strata i vandsøjlen. Under kraftig sydgående strøm viste hydrografien...

  18. Raman evidence of the formation of LT-LiCoO 2 thin layers on NiO in molten carbonate at 650°C

    Science.gov (United States)

    Mendoza, L.; Baddour-Hadjean, R.; Cassir, M.; Pereira-Ramos, J. P.

    2004-03-01

    The structural evolution of thin layers of Co 3O 4 elaborated on nickel-based substrates in the Li 2CO 3-Na 2CO 3 carbonate eutectic at 650 °C as a function of time immersion is reported. Raman microspectrometry has been applied in order to provide more information on the nature of the protective cobalt oxide layers. The typical Raman fingerprint of the LT-LiCoO 2 compound has been obtained, with four well defined bands at 449, 484, 590 and 605 cm -1, while XRD data are unable to distinguish the layered phase (HT) from the spinel one (LT). The mechanical stability of such films does not exceed 10 h in direct contact with the molten carbonate bulk at 650 °C; nevertheless, these conditions are much more corrosive than in a molten carbonate fuel cell (MCFC).

  19. The effect of triiodothyronine (L-T3) and weight loss on sex-hormone binding globulin (SHBG) in hirsute obese women

    International Nuclear Information System (INIS)

    Cavaliere, H.; Medeiros Neto, G.A.

    1984-01-01

    The effect of a 60-day period of treatment with L-T 3 (200 μg/day) was evaluated in hirsute obese women and normal controls. The obese patients were also submitted to a low calorie high protein. Mean initial weight significantly declined with a significant lowering of the mean DHEA-S leves. There was changes in serum T 3 rose in both obese and normal patients. Serum sex-hormone binding globulin levels at baseline studies were significantly higher in normal controls than in obese patients. At the end of de 60-day period of L-T 3 administration it was observed in both groups a 2-4 fold increase in serum SHBG levels but normal controls had significantly higher mean values than obese individuals. (M.A.C.) [pt

  20. Optimization of friction and wear behaviour of Al7075-Al2O3-B4C metal matrix composites using Taguchi method

    Science.gov (United States)

    Dhanalakshmi, S.; Mohanasundararaju, N.; Venkatakrishnan, P. G.; Karthik, V.

    2018-02-01

    The present study deals with investigations relating to dry sliding wear behaviour of the Al 7075 alloy, reinforced with Al2O3 and B4C. The hybrid composites are produced through Liquid Metallurgy route - Stir casting method. The amount of Al2O3 particles is varied as 3, 6, 9, 12 and 15 wt% and the amount of B4C is kept constant as 3wt%. Experiments were conducted based on the plan of experiments generated through Taguchi’s technique. A L27 Orthogonal array was selected for analysis of the data. The investigation is to find the effect of applied load, sliding speed and sliding distance on wear rate and Coefficient of Friction (COF) of the hybrid Al7075- Al2O3-B4C composite and to determine the optimal parameters for obtaining minimum wear rate. The samples were examined using scanning electronic microscopy after wear testing and analyzed.

  1. Influence of B4C-doping and high-energy ball milling on phase formation and critical current density of (Bi,Pb)-2223 HTS

    Science.gov (United States)

    Margiani, N. G.; Mumladze, G. A.; Adamia, Z. A.; Kuzanyan, A. S.; Zhghamadze, V. V.

    2018-05-01

    In this paper, the combined effects of B4C-doping and planetary ball milling on the phase evolution, microstructure and transport properties of Bi1.7Pb0.3Sr2Ca2Cu3Oy(B4C)x HTS with x = 0 ÷ 0.125 were studied through X-ray diffraction (XRD), scanning electron microscopy (SEM), resistivity and critical current density measurements. Obtained results have shown that B4C additive leads to the strong acceleration of high-Tc phase formation and substantial enhancement in Jc. High-energy ball milling seems to produce a more homogeneous distribution of refined doped particles in the (Bi,Pb)-2223 HTS which results in an improved intergranular flux pinning and better self-field Jc performance.

  2. Effects of B4C Addition on the Laser Beam Welding Characteristics of Al/SiC MMCs Produced By P/M

    Directory of Open Access Journals (Sweden)

    Serdar KARAOĞLU

    2011-01-01

    Full Text Available Fusion weldability characteristics of metal matrix composites (MMC produced by powder metallurgy (P/M are usually insufficient due to unwanted micro-structural changes that occur during welding. This study aims to investigate the effects of B4C addition as reinforcement on the weld quality of Al/SiC MMCs. After the production of Al/SiC MMCs by P/M with or without the addition of B4C, laser beam welding (LBW characteristics of the materials were investigated by focusing on the integrity of the welds. Optical microscopy (OM, scanning electron microscopy (SEM, and energy dispersive X-ray analysis (EDX were utilized for the characterization of the welds. Results show that Al/SiC MMCs produced by P/M can not be easily welded by LBW, but weldability characteristics of the material can be improved by the addition of B4C.

  3. Preparation and characteristics of epoxy/clay/B4C nanocomposite at high concentration of boron carbide for neutron shielding application

    Science.gov (United States)

    Kiani, Mohammad Amin; Ahmadi, Seyed Javad; Outokesh, Mohammad; Adeli, Ruhollah; Mohammadi, Aghil

    2017-12-01

    In this research, the characteristics of the prepared samples in epoxy matrix by means of X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS), as well as scanning electron microscope (SEM) are evaluated. Meanwhile, the obtained mechanical properties of the specimen are investigated. Thermogravimetric analysis (TGA) is also employed to evaluate the thermal degradation of manufactured nanocomposites. The thermal neutron absorption properties of nanocomposites containing 3 wt% of montmorillonite nanoclay (closite30B) have been studied experimentally, using an Am-Be point source. Mechanical tests reveal that the higher B4C concentrations, the more tensile strengths, but lower Young's modulus in all samples under consideration. TGA analysis also shows that thermal stability of the nanocomposite, increases in presence of B4C. Finally, neutron absorption analysis shows that increasing the B4C concentration leads to a nonlinearly build-up of neutron absorption cross section.

  4. Friction Stir Welding of Al-B4C Composite Fabricated by Accumulative Roll Bonding: Evaluation of Microstructure and Mechanical Behavior

    Science.gov (United States)

    Moradi Faradonbeh, Alireza; Shamanian, Morteza; Edris, Hossein; Paidar, Moslem; Bozkurt, Yahya

    2018-02-01

    In this investigation, friction stir welding (FSW) of Al-B4C composite fabricated by 10 cycles accumulative roll bonding was conducted. In order to investigate the influences of pin geometry on microstructure and mechanical properties, four different pin geometries (cylindrical, square, triangular and hexagonal) were selected. It was found that FSW parameters had a major effect on the fragmentation and distribution of reinforcement particles in stir zone. When the tool travel speed was increased, the distribution of B4C particles was become gradually uniform in the aluminum matrix. The effect of tool rotational speed on the peak temperature was determined to be greater than the tool travel speed. The attained data of tensile properties and microhardness tests showed that the tool travel speed had bilateral effect on the tensile strength. The maximum tensile joint efficiency was obtained as 238% for FSWed of Al-2%B4C composite to annealed base Al sheet.

  5. Celecoxib and tauro-ursodeoxycholic acid co-treatment inhibits cell growth in familial adenomatous polyposis derived LT97 colon adenoma cells

    Energy Technology Data Exchange (ETDEWEB)

    Heumen, Bjorn W.H. van, E-mail: b.vanheumen@mdl.umcn.nl [Department of Gastroenterology and Hepatology, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Roelofs, Hennie M.J.; Morsche, Rene H.M. te [Department of Gastroenterology and Hepatology, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Marian, Brigitte [Institute of Cancer Research, Wien University, Vienna (Austria); Nagengast, Fokko M.; Peters, Wilbert H.M. [Department of Gastroenterology and Hepatology, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands)

    2012-04-15

    Chemoprevention would be a desirable strategy to avoid duodenectomy in patients with familial adenomatous polyposis (FAP) suffering from duodenal adenomatosis. We investigated the in vitro effects on cell proliferation, apoptosis, and COX-2 expression of the potential chemopreventives celecoxib and tauro-ursodeoxycholic acid (UDCA). HT-29 colon cancer cells and LT97 colorectal micro-adenoma cells derived from a patient with FAP, were exposed to low dose celecoxib and UDCA alone or in combination with tauro-cholic acid (CA) and tauro-chenodeoxycholic acid (CDCA), mimicking bile of FAP patients treated with UDCA. In HT-29 cells, co-treatment with low dose celecoxib and UDCA resulted in a decreased cell growth (14-17%, p < 0.01). A more pronounced decrease (23-27%, p < 0.01) was observed in LT97 cells. Cell growth of HT-29 cells exposed to 'artificial bile' enriched with UDCA, was decreased (p < 0.001), either in the absence or presence of celecoxib. In LT97 cells incubated with 'artificial bile' enriched with UDCA, cell growth was decreased only in the presence of celecoxib (p < 0.05). No clear evidence was found for involvement of proliferating cell nuclear antigen, caspase-3, or COX-2 in the cellular processes leading to the observed changes in cell growth. In conclusion, co-treatment with low dose celecoxib and UDCA has growth inhibitory effects on colorectal adenoma cells derived from a patient with FAP, and further research on this combination as promising chemopreventive strategy is desired. -- Highlights: Black-Right-Pointing-Pointer Celecoxib and UDCA acid co-treatment decreases cell growth in colon tumor cells. Black-Right-Pointing-Pointer UDCA enriched 'artificial bile' decreases LT-97 cell growth only in presence of celecoxib. Black-Right-Pointing-Pointer PCNA, caspase-3, nor COX-2 seem to be involved in the observed changes in cell growth.

  6. Celecoxib and tauro-ursodeoxycholic acid co-treatment inhibits cell growth in familial adenomatous polyposis derived LT97 colon adenoma cells

    International Nuclear Information System (INIS)

    Heumen, Bjorn W.H. van; Roelofs, Hennie M.J.; Morsche, René H.M. te; Marian, Brigitte; Nagengast, Fokko M.; Peters, Wilbert H.M.

    2012-01-01

    Chemoprevention would be a desirable strategy to avoid duodenectomy in patients with familial adenomatous polyposis (FAP) suffering from duodenal adenomatosis. We investigated the in vitro effects on cell proliferation, apoptosis, and COX-2 expression of the potential chemopreventives celecoxib and tauro-ursodeoxycholic acid (UDCA). HT-29 colon cancer cells and LT97 colorectal micro-adenoma cells derived from a patient with FAP, were exposed to low dose celecoxib and UDCA alone or in combination with tauro-cholic acid (CA) and tauro-chenodeoxycholic acid (CDCA), mimicking bile of FAP patients treated with UDCA. In HT-29 cells, co-treatment with low dose celecoxib and UDCA resulted in a decreased cell growth (14–17%, p < 0.01). A more pronounced decrease (23–27%, p < 0.01) was observed in LT97 cells. Cell growth of HT-29 cells exposed to ‘artificial bile’ enriched with UDCA, was decreased (p < 0.001), either in the absence or presence of celecoxib. In LT97 cells incubated with ‘artificial bile’ enriched with UDCA, cell growth was decreased only in the presence of celecoxib (p < 0.05). No clear evidence was found for involvement of proliferating cell nuclear antigen, caspase-3, or COX-2 in the cellular processes leading to the observed changes in cell growth. In conclusion, co-treatment with low dose celecoxib and UDCA has growth inhibitory effects on colorectal adenoma cells derived from a patient with FAP, and further research on this combination as promising chemopreventive strategy is desired. -- Highlights: ► Celecoxib and UDCA acid co-treatment decreases cell growth in colon tumor cells. ► UDCA enriched ‘artificial bile’ decreases LT-97 cell growth only in presence of celecoxib. ► PCNA, caspase-3, nor COX-2 seem to be involved in the observed changes in cell growth.

  7. A SEARCH FOR L/T TRANSITION DWARFS WITH Pan-STARRS1 AND WISE: DISCOVERY OF SEVEN NEARBY OBJECTS INCLUDING TWO CANDIDATE SPECTROSCOPIC VARIABLES

    International Nuclear Information System (INIS)

    Best, William M. J.; Liu, Michael C.; Magnier, Eugene A.; Aller, Kimberly M.; Burgett, W. S.; Chambers, K. C.; Hodapp, K. W.; Kaiser, N.; Kudritzki, R.-P.; Morgan, J. S.; Tonry, J. L.; Wainscoat, R. J.; Deacon, Niall R.; Dupuy, Trent J.; Redstone, Joshua; Price, P. A.

    2013-01-01

    We present initial results from a wide-field (30,000 deg 2 ) search for L/T transition brown dwarfs within 25 pc using the Pan-STARRS1 and Wide-field Infrared Survey Explorer (WISE) surveys. Previous large-area searches have been incomplete for L/T transition dwarfs, because these objects are faint in optical bands and have near-infrared (near-IR) colors that are difficult to distinguish from background stars. To overcome these obstacles, we have cross-matched the Pan-STARRS1 (optical) and WISE (mid-IR) catalogs to produce a unique multi-wavelength database for finding ultracool dwarfs. As part of our initial discoveries, we have identified seven brown dwarfs in the L/T transition within 9-15 pc of the Sun. The L9.5 dwarf PSO J140.2308+45.6487 and the T1.5 dwarf PSO J307.6784+07.8263 (both independently discovered by Mace et al.) show possible spectroscopic variability at the Y and J bands. Two more objects in our sample show evidence of photometric J-band variability, and two others are candidate unresolved binaries based on their spectra. We expect our full search to yield a well-defined, volume-limited sample of L/T transition dwarfs that will include many new targets for study of this complex regime. PSO J307.6784+07.8263 in particular may be an excellent candidate for in-depth study of variability, given its brightness (J = 14.2 mag) and proximity (11 pc)

  8. A SEARCH FOR L/T TRANSITION DWARFS WITH Pan-STARRS1 AND WISE: DISCOVERY OF SEVEN NEARBY OBJECTS INCLUDING TWO CANDIDATE SPECTROSCOPIC VARIABLES

    Energy Technology Data Exchange (ETDEWEB)

    Best, William M. J.; Liu, Michael C.; Magnier, Eugene A.; Aller, Kimberly M.; Burgett, W. S.; Chambers, K. C.; Hodapp, K. W.; Kaiser, N.; Kudritzki, R.-P.; Morgan, J. S.; Tonry, J. L.; Wainscoat, R. J. [Institute for Astronomy, University of Hawaii at Manoa, Honolulu, HI 96822 (United States); Deacon, Niall R. [Max Planck Institute for Astronomy, Koenigstuhl 17, D-69117 Heidelberg (Germany); Dupuy, Trent J. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Redstone, Joshua [Facebook, 335 Madison Ave, New York, NY 10017-4677 (United States); Price, P. A., E-mail: wbest@ifa.hawaii.edu [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States)

    2013-11-10

    We present initial results from a wide-field (30,000 deg{sup 2}) search for L/T transition brown dwarfs within 25 pc using the Pan-STARRS1 and Wide-field Infrared Survey Explorer (WISE) surveys. Previous large-area searches have been incomplete for L/T transition dwarfs, because these objects are faint in optical bands and have near-infrared (near-IR) colors that are difficult to distinguish from background stars. To overcome these obstacles, we have cross-matched the Pan-STARRS1 (optical) and WISE (mid-IR) catalogs to produce a unique multi-wavelength database for finding ultracool dwarfs. As part of our initial discoveries, we have identified seven brown dwarfs in the L/T transition within 9-15 pc of the Sun. The L9.5 dwarf PSO J140.2308+45.6487 and the T1.5 dwarf PSO J307.6784+07.8263 (both independently discovered by Mace et al.) show possible spectroscopic variability at the Y and J bands. Two more objects in our sample show evidence of photometric J-band variability, and two others are candidate unresolved binaries based on their spectra. We expect our full search to yield a well-defined, volume-limited sample of L/T transition dwarfs that will include many new targets for study of this complex regime. PSO J307.6784+07.8263 in particular may be an excellent candidate for in-depth study of variability, given its brightness (J = 14.2 mag) and proximity (11 pc)

  9. Characteristic of Lamb Sausages Fermented by Indonesian Meat-Derived Probiotic, Lactobacillus plantarum IIA-2C12 and Lactobacillus acidophilus IIA-2B4

    Directory of Open Access Journals (Sweden)

    Noraimah Binti Sulaiman

    2016-08-01

    Full Text Available Probiotic is a group of microorganism, mainly from lactic acid bacteria (LAB, widely used to increase functionality of various foodstuffs, including lamb which was limited by its goaty odor and short life issue. This study aimed to evaluate the characteristic of lamb sausages fermented by either Lactobacillus plantarum IIA-2C12 or L. acidophilus IIA-2B4 isolated from local cattle in Indonesia, and stored for 21 days at low temperature (4oC. Fermented lamb sausages were made with the addition of L. plantarum IIA-2C12 and L. acidophilus IIA-2B4 with three replications. The result showed that pH value, protein, and cholesterol contents of the sausages with addition of L. acidophilus IIA-2B4 were higher (P<0.05 than that of L. plantarum IIA-2C12. Meanwhile, the sausage fermented with L. plantarum IIA-2C12 had higher titratable acid (TA value, texture, and the content of fat, carbohydrate, tyrosine, lysine, myristoleic (C14:1, pentadecanoic (C15:0, heneicosanoic (C21:0 and cis-11-eicosatrienoic (C20:1 as compared to that of  L. acidophilus 2C12-2B4. Final population of LAB in the sausage fermented by L. plantarum IIA-2C12 was also higher than that of L. acidophilus IIA-2B4, yet both can be categorized as a probiotic. The differences between characteristics of the physicochemical traits and microbiological quality of the sausage fermentation associated with the addition of L. plantarum IIA-2C12 or L. acidophilus IIA-2B4. The 21 days of storage at cold temperatures with probiotics addition could extend shelf life and maintain quality of fermented sausage.

  10. The effect of rider weight and additional weight in Icelandic horses in tölt: part II. Stride parameters responses.

    Science.gov (United States)

    Gunnarsson, V; Stefánsdóttir, G J; Jansson, A; Roepstorff, L

    2017-09-01

    This study investigated the effects of rider weight in the BW ratio (BWR) range common for Icelandic horses (20% to 35%), on stride parameters in tölt in Icelandic horses. The kinematics of eight experienced Icelandic school horses were measured during an incremental exercise test using a high-speed camera (300 frames/s). Each horse performed five phases (642 m each) in tölt at a BWR between rider (including saddle) and horse starting at 20% (BWR20) and increasing to 25% (BWR25), 30% (BWR30), 35% (BWR35) and finally 20% (BWR20b) was repeated. One professional rider rode all horses and weight (lead) was added to saddle and rider as needed. For each phase, eight strides at speed of 5.5 m/s were analyzed for stride duration, stride frequency, stride length, duty factor (DF), lateral advanced placement, lateral advanced liftoff, unipedal support (UPS), bipedal support (BPS) and height of front leg action. Stride length became shorter (Y=2.73-0.004x; P0.05). In conclusion, increased BWR decreased stride length and increased DF proportionally to the same extent in all limbs, whereas BPS increased at the expense of decreased UPS. These changes can be expected to decrease tölt quality when subjectively evaluated according to the breeding goals for the Icelandic horse. However, beat, symmetry and height of front leg lifting were not affected by BWR.

  11. Production of arachidonic and linoleic acid metabolites by guinea pig tracheal epithelial cells

    International Nuclear Information System (INIS)

    Oosthuizen, M.J.; Engels, F.; Van Esch, B.; Henricks, P.A.; Nijkamp, F.P.

    1990-01-01

    Pulmonary epithelial cells may be responsible for regulating airway smooth muscle function, in part by release of fatty acid-derived mediators. Incubation of isolated guinea pig tracheal epithelial cells with radiolabeled arachidonic acid (AA) leads to the production of 5- and 15-hydroxyeicosatetraenoic acid (5- and 15-HETE) and smaller amounts of leukotriene (LT) B4 and C4 and 12-hydroxyheptadecatrienoic acid (HHT). Epithelial cells also are able to release linoleic acid (LA) metabolites. Incubation with radiolabeled linoleic acid leads to the formation of 9- and 13-hydroxyoctadecadienoic acid (9- and 13-HODE). The biological significance of these mediators produced by epithelial cells is discussed

  12. Microstructure and electrical properties of slug-type resistors based on B4C and TiC - ESCA - XPS and impedance spectroscopy investigations

    International Nuclear Information System (INIS)

    Klimiec, E.; Zaraska, W.; Stobiecki, T.; Bak, W.; Starzyk, F.

    2000-01-01

    The microstructure and electrical properties of slug-type resistors based on B 4 C and TiC were investigated. From XPS measurements was deducted that Ti in TiO 2 is in intermediate oxidation number between Ti +4 and Ti +3 . The impedance of both type of resistors is independent on frequency in the range from 10 3 to 10 4 Hz, only very subtle differences above 10 4 Hz are observed. The metallic type conductivity in TiC and semiconducting in B 4 C was established. (author)

  13. Near-net shape manufacture of B4C–Co and ZrC–Co composites by slip casting and pressureless sintering

    DEFF Research Database (Denmark)

    Ortiz, Angel L.; Leal, Victor Manuel Candelario; Moreno, Rodrigo

    2017-01-01

    Fabrication of near-net shaped B4C–Co and ZrC–Co composites by slip casting and pressureless sintering is described. It is shown how B4C–Co and ZrC–Co concentrated suspensions can be prepared by aqueous colloidal processing, and optimized (in terms of pH, deflocculant contents, and sonication tim...... is given for these observations, and general implications are discussed for the near-net shape manufacture of these and similar carbide-metal composites for use in engineering applications....

  14. Urinary leukotriene E(4), eosinophil protein X, and nasal eosinophil cationic protein are not associated with respiratory symptoms in 1-year-old children.

    Science.gov (United States)

    Wojnarowski, C; Halmerbauer, G; Mayatepek, E; Gartner, C; Frischer, T; Forster, J; Kuehr, J

    2001-09-01

    Eosinophilic airways inflammation forms the pathophysiologic basis for a proportion of children at risk of developing recurrent wheezing. Early preventive measures and/or anti-inflammatory treatment may be guided by the identification of such children. We aimed to study the relationship between respiratory symptoms and indirect markers of airway inflammation. We measured eosinophil protein X (EPX) and leukotriene E(4) (LTE(4)) in urine, as well as eosinophil cationic protein (ECP) in nasal lavages, in a random sample of 1-year-old children with a family history of atopy who participated in an international multicenter study on the prevention of allergy in Europe. For urine analyses, 10 children with upper respiratory illness and 19 healthy children without a family history of atopy were also enrolled. Endogenous urinary LTE(4) was separated by HPLC and determined by enzyme immunoassay with a specific antibody. The concentrations of nasal ECP and urinary EPX were determined by RIA analysis. One hundred and ten children (mean age: 1.05+/-0.1 years) were enrolled. Prolonged coughing during the first year of life was reported in 29 children, wheezy breathing in 17 children, and dry skin in 33 children. A doctor's diagnosis of wheezy bronchitis was given to 17 children. Sensitization to dust mites (specific IgE > or =1.43 ML/units) was detected in two children. Children with a doctor's diagnosis of atopic dermatitis within the first 12 months of life (n=6) had significantly higher urinary EPX than children without this (66.7 vs 30.1 microg/mmol creatinine, P=0.01). Urinary excretion of EPX and LTE4 showed a weak correlation (r=0.22, P=0.02). There were no significant differences in urinary excretion of EPX and LTE(4) or nasal ECP between children with and without respiratory symptoms (P>0.1). At the age of 1 year, urinary EPX is increased in children with atopic dermatitis. With regard to respiratory symptoms, urinary and nasal inflammatory parameters are not helpful in

  15. The effect of rider weight and additional weight in Icelandic horses in tölt: part I. Physiological responses.

    Science.gov (United States)

    Stefánsdóttir, G J; Gunnarsson, V; Roepstorff, L; Ragnarsson, S; Jansson, A

    2017-09-01

    This study examined the effect of increasing BW ratio (BWR) between rider and horse, in the BWR range common for Icelandic horses (20% to 35%), on heart rate (HR), plasma lactate concentration (Lac), BWR at Lac 4 mmol/l (W4), breathing frequency (BF), rectal temperature (RT) and hematocrit (Hct) in Icelandic horses. In total, eight experienced school-horses were used in an incremental exercise test performed outdoors on an oval riding track and one rider rode all horses. The exercise test consisted of five phases (each 642 m) in tölt, a four-beat symmetrical gait, at a speed of 5.4±0.1 m/s (mean±SD), where BWR between rider (including saddle) and horse started at 20% (BWR20), was increased to 25% (BWR25), 30% (BWR30), and 35% (BWR35) and finally decreased to 20% (BWR20b). Between phases, the horses were stopped (~5.5 min) to add lead weights to specially adjusted saddle bags and a vest on the rider. Heart rate was measured during warm-up, the exercise test and after 5, 15 and 30 min of recovery and blood samples were taken and BF recorded at rest, and at end of each of these aforementioned occasions. Rectal temperature was measured at rest, at end of the exercise test and after a 30-min recovery period. Body size and body condition score (BCS) were registered and a clinical examination performed on the day before the test and for 2 days after. Heart rate and BF increased linearly (P0.05), but negative correlations (Phorses had no clinical remarks on palpation and at walk 1 and 2 days after the test. In conclusion, increasing BWR from 20% to 35% resulted in increased HR, Lac, RT and BF responses in the test group of experienced adult Icelandic riding horses. The horses mainly worked aerobically until BWR reached 22.7%, but considerable individual differences (17.0% to 27.5%) existed that were not linked to horse size, but to back BCS.

  16. A Novel Bifunctional Amino Acid Racemase With Multiple Substrate Specificity, MalY From Lactobacillus sakei LT-13: Genome-Based Identification and Enzymological Characterization

    Directory of Open Access Journals (Sweden)

    Shiro Kato

    2018-03-01

    Full Text Available The Lactobacillus sakei strain LK-145 isolated from Moto, a starter of sake, produces potentially large amounts of three D-amino acids, D-Ala, D-Glu, and D-Asp, in a medium containing amylase-digested rice as a carbon source. The comparison of metabolic pathways deduced from the complete genome sequence of strain LK-145 to the type culture strain of Lactobacillus sakei strain LT-13 showed that the L- and D-amino acid metabolic pathways are similar between the two strains. However, a marked difference was observed in the putative cysteine/methionine metabolic pathways of strain LK-145 and LT-13. The cystathionine β-lyase homolog gene malY was annotated only in the genome of strain LT-13. Cystathionine β-lyase is an important enzyme in the cysteine/methionine metabolic pathway that catalyzes the conversion of L-cystathionine into L-homocysteine. In addition to malY, most genome-sequenced strains of L. sakei including LT-13 lacked the homologous genes encoding other putative enzymes in this pathway. Accordingly, the cysteine/methionine metabolic pathway likely does not function well in almost all strains of L. sakei. We succeeded in cloning and expressing the malY gene from strain LT-13 (Ls-malY in the cells of Escherichia coli BL21 (DE3 and characterized the enzymological properties of Ls-MalY. Spectral analysis of purified Ls-MalY showed that Ls-MalY contained a pyridoxal 5′-phosphate (PLP as a cofactor, and this observation agreed well with the prediction based on its primary structure. Ls-MalY showed amino acid racemase activity and cystathionine β-lyase activity. Ls-MalY showed amino acid racemase activities in various amino acids, such as Ala, Arg, Asn, Glu, Gln, His, Leu, Lys, Met, Ser, Thr, Trp, and Val. Mutational analysis revealed that the -amino group of Lys233 in the primary structure of Ls-MalY likely bound to PLP, and Lys233 was an essential residue for Ls-MalY to catalyze both the amino acid racemase and β-lyase reactions. In

  17. The effect of strontium on the microstructure, porosity and tensile properties of A356-10%B4C cast composite

    International Nuclear Information System (INIS)

    Lashgari, H.R.; Emamy, M.; Razaghian, A.; Najimi, A.A.

    2009-01-01

    This study was undertaken to investigate the effect of different concentrations of strontium (0.05%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5% and 1%) on the microstructure, porosity content and tensile properties of A356-10%B 4 C particulate metal matrix composite. In this work, the matrix alloy and composite were characterized by optical microscope, scanning electron microscope equipped with EDS and XRD. The composite ingots were made by stir casting process. The results showed that the addition of 0.03%Sr strongly modified silicon eutectic phase in A356 monolithic alloy, but 0.5%Sr was needed to complete the modification of A356-10%B 4 C composite. Results also demonstrated that Sr addition increases shrinkage porosity and generates new intermetallics in the microstructure. Further investigations on tensile tests revealed optimum strontium levels for improving tensile properties. In the point of fracture behavior of the composite, modified specimens with 0.2%Sr showed broken B 4 C particles and acceptable cohesion between B 4 C and matrix.

  18. Heat treatment effect on the microstructure, tensile properties and dry sliding wear behavior of A356-10%B4C cast composites

    International Nuclear Information System (INIS)

    Lashgari, H.R.; Zangeneh, Sh.; Shahmir, H.; Saghafi, M.; Emamy, M.

    2010-01-01

    In present paper, an attempt was made to examine the influence of T6 heat treatment (solution treatment at 540 o C for 5 h, quenching in hot water and artificial aging at 170 o C for 8 h) on the microstructure, tensile properties and dry sliding wear behavior of A356-10%B 4 C cast composites. The composite ingots were made by stir casting process. In this work, the matrix alloy and composite were characterized by optical microscope, scanning electron microscope equipped with energy dispersive X-ray spectroscopy, tensile tests and conventional pin-on-disk experiment. The obtained results showed that in Al-B 4 C composite, T6 treatment was a dominant factor on the hardness improvement in comparison with hardness increasing due to the addition of B 4 C hard particles. In addition, T6 treatment can contribute to the strong bonding between B 4 C and matrix alloy and also it can change eutectic silicon morphology from acicular to near spherical. This case can lead to higher strength and wear properties of heat treated metal matrix composites in comparison with unheat treated state. Observation of worn surfaces indicated detachment of mechanically mixed layer which can primarily due to the delamination wear mechanism under higher applied load.

  19. Stratification by Smoking Status Reveals an Association of CHRNA5-A3-B4 Genotype with Body Mass Index in Never Smokers

    NARCIS (Netherlands)

    Taylor, A.E.; Morris, R.W.; Fluharty, M.E.; Bjorngaard, J.H.; Asvold, B.O.; Gabrielsen, M.E.; Campbell, A.; Marioni, R.; Kumari, M.; Hällfors, J.; Männistö, S.; Marques-Vidal, P.; Kaakinen, M.; Cavadino, A.; Postmus, I.; Husemoen, L.L.N.; Skaaby, T.; Ahluwalia, T.S.; Treur, J.L.; Willemsen, G.; Dale, C.; Wannamethee, S.G.; Lahti, J.; Palotie, A.; Räikkönen, K.; Kisialiou, A.; McConnachie, A.; Padmanabhan, S.; Wong, A.; Dalgard, C.; Paternoster, L.; Ben-Shlomo, Y.; Tyrrell, J.; Horwood, L.J.; Fergusson, D.; Kennedy, M.A.; Frayling, T.M.; Nohr, E.A.; Christiansen, L.; Ohm Kyvik, K.; Kuh, D; Watt, G.; Eriksson, J.; Whincup, P.H.; Vink, J.M.; Boomsma, D.I.; Davey Smith, G.; Lawlor, D.; Linneberg, A.; Ford, I.; Jukema, J.W.; Power, C.; Hyppönen, E.; Järvelin, M.R.; Preisig, M.; Borodulin, K.; Kaprio, J.; Kivimaki, M.; Smith, B.H.; Hayward, C.; Romundstad, P.R.; Sørensen, T.I.A.; Munafo, M.R.; Sattar, N.

    2014-01-01

    We previously used a single nucleotide polymorphism (SNP) in the CHRNA5-A3-B4 gene cluster associated with heaviness of smoking within smokers to confirm the causal effect of smoking in reducing body mass index (BMI) in a Mendelian randomisation analysis. While seeking to extend these findings in a

  20. Stratification by smoking status reveals an association of CHRNA5-A3-B4 genotype with body mass index in never smokers

    NARCIS (Netherlands)

    Taylor, A.E.; Morris, R.W.; Fluharty, M.E.; Björngaard, J.H.; Asvold, B.A.; Gabrielsen, M.E.; Campbell, A.; Marioni, R.E.; Kumari, M.; Hallfors, J.; Mannisto, S.; Marques-Vidal, P.; Kaakinen, M.; Cavadino, A.; Postmus, I.; Husemoen, L.L.N.; Skaaby, T.; Ahluwalia, T.V.S.; Treur, J.L.; Willemsen, G.; Dale, C.E.; Wannamethee, S.G.; Lahti, J.; Palotie, A.; Raikkonen, K.; Kisialiou, A.; McConnachie, A.; Padmanabhan, S.; Wong, A.; Dalgard, C.; Paternoster, L.; Ben-Shlomo, Y.; Tyrrell, J.; Horwood, J.; Fergusson, D.M.; Kennedy, M.A.; Frayling, T.; Nohr, E.A.; Christiansen, L.; Kyvik, K.O.; Kuh, D.; Watt, G.; Eriksson, J.; Whincup, P.H.; Vink, J.M.; Boomsma, D.I.; Smith, G.D.; Lawlor, D.A.; Linneberg, A.; Ford, I.; Jukema, J.W.; Power, C.; Hypponen, E.; Jarvelin, M.R.; Preisig, M.; Borodulin, K.; Kaprio, J.; Kivimaki, M.; Smith, B.H.; Hayward, C.; Romundstad, P.R.; Sorensen, T.I.A.; Munafò, M.R.; Sattar, N.

    2014-01-01

    We previously used a single nucleotide polymorphism (SNP) in the CHRNA5-A3-B4 gene cluster associated with heaviness of smoking within smokers to confirm the causal effect of smoking in reducing body mass index (BMI) in a Mendelian randomisation analysis. While seeking to extend these findings in a