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Sample records for alpha 1-adrenoceptor antagonist

  1. Rational design, synthesis, biologic evaluation, and structure-activity relationship studies of novel 1-indanone alpha(1)-adrenoceptor antagonists.

    Li, Minyong; Xia, Lin

    2007-11-01

    In the present report, a novel series of 1-indanone alpha(1)-adrenoceptor antagonists were designed and synthesized based on 3D-pharmacophore model. Their in vitro alpha(1)-adrenoceptor antagonistic assay showed that three compounds (2a, 2m, and 2o) had similar or improved alpha(1)-adrenoceptor antagonistic activities relative to the positive control prazosin. Based on these results, a three-dimensional quantitative structure-activity relationship study was performed using a Self-Organizing Molecular Field Analysis method to provide insight for the future development of alpha(1)-adrenoceptor antagonists.

  2. The antagonistic effect of antipsychotic drugs on a HEK293 cell line stably expressing human alpha(1A1)-adrenoceptors

    Nourian, Zahra; Mulvany, Michael J; Nielsen, Karsten Bork

    2008-01-01

    challenged with phenylephrine (EC(50)=1.61x10(-8) M). From Schild analysis, prazosin, sertindole, risperidone, and haloperidol caused a concentration-dependent, rightward shift of the cumulative concentration-response curves for phenylephrine in cells expressing human recombinant alpha(1A1)-adrenoceptors...... human alpha(1A1)-adrenoceptors in competition binding studies confirmed much higher antagonist affinity of sertindole and risperidone than haloperidol for these receptors. In summary, it can be concluded that there is an approximately 10-fold higher adrenoceptor affinity of risperidone and sertindole...... for human alpha(1A1)-adrenoceptors compared to haloperidol. These findings are consistent with the observation that risperidone and sertindole have a higher incidence of orthostatic hypotension than haloperidol....

  3. Differential vascular alpha1-adrenoceptor antagonism by tamsulosin and terazosin

    Schäfers, R. F.; Fokuhl, B.; Wasmuth, A.; Schumacher, H.; Taguchi, K.; de Mey, C.; Philipp, T.; Michel, M. C.

    1999-01-01

    AIMS: In patients with lower urinary tract symptoms suggestive of benign prostatic obstruction the alpha1-adrenoceptor antagonist terazosin lowers blood pressure whereas only very small if any alterations were reported with the alpha1-adrenoceptor antagonist tamsulosin. Therefore, we have compared

  4. Classification of alpha 1-adrenoceptor subtypes

    Michel, M. C.; Kenny, B.; Schwinn, D. A.

    1995-01-01

    Two alpha 1-adrenoceptor subtypes (alpha 1A and alpha 1B) have been detected in various tissues by pharmacological techniques, and three distinct cDNAs encoding alpha 1-adrenoceptor subtypes have been cloned. The profile of an increasing number of subtype-selective compounds at cloned and endogenous

  5. Effects of alpha1-adrenoceptor antagonist (tamsulosin) on incident of ejaculation and semen quality in the goat.

    Kimsakulvech, S; Suttiyotin, P; Pinyopummin, A

    2015-04-01

    Male temporary contraception is occasionally required in some animals. Alpha1-adrenoceptor antagonist (tamsulosin) can cause ejaculation disorder. Two sets of Latin square were applied to six male goats to received either normal saline, dimethylsulphoxide or tamsulosin (179.8 nmol kg(-1) ) at 1-week interval. Semen collection and libido scoring were undertaken at 3, 6 and 24 h post-injection. For ejaculated semen, its quality was evaluated. Physiological measurements including body temperature, respiration and heart rates were measured before injection and at 30 min before semen collection. The results showed that libido score and physiological changes were not affected by treatments and time periods. Anejaculation was observed in 11 (91.7%), 5 (41.7%) and 1 (8.3%) males at 3, 6 and 24 h post-tamsulosin injection respectively. The incidence returned to normal when compared with control groups at 24 h. The percentages of motile and live spermatozoa at 6 h post-tamsulosin injection were significantly lower (P tamsulosin had temporary effects on ejaculation and semen quality without reducing sex desire and physiological functions in male goats. © 2014 Blackwell Verlag GmbH.

  6. New {alpha}{sub 1}-adrenoceptor antagonists derived from the antipsychotic sertindole - carbon-11 labelling and pet examination of brain uptake in the cynomolgus monkey

    Balle, Thomas E-mail: tb@dfuni.dk; Halldin, Christer; Andersen, Linus; Hjorth Alifrangis, Lene; Badolo, Lassina; Gjervig Jensen, Klaus; Chou, Y.-W.; Andersen, Kim; Perregaard, Jens; Farde, Lars

    2004-04-01

    Central {alpha}{sub 1}-adrenergic receptors are potential targets for recently developed antipsychotic drugs. Two new 11C labeled potent and selective {alpha}{sub 1}-adrenoceptor antagonists, 1- [2- [4-[1-(4-fluorophenyl)-5-(2-[{sup 11}C]methyl-tetrazol-5-yl)-1H-indol-3-yl]-1- pipridinyl]ethyl]-imidazolidin-2-one ([{sup 11}C]2) and 1- [2- [4-[1-(4-fluorophenyl)-5-(1-[{sup 11}C]methyl-(1,2,3-triazol-4-yl) -1H-indol-3-yl]- 1-piperidinyl]ethyl]-imidazolidin-2-one ([{sup 11}C]3) were prepared and evaluated for imaging of central {alpha}{sub 1}-adrenergic receptors in the cynomolgus monkey brain. For both compounds, the total brain radioactivity was only about 0.6% of the radioactivity injected i.v. There was no evident binding in regions known to contain {alpha}{sub 1}-adrenoceptors. This observation suggests that the affinity of the radioligands in primates in vivo is not sufficient to provide a signal for specific binding that can be differentiated from the background. In addition, active efflux by P-glycoprotein may be responsible for the low total brain-uptake of the two radioligands. Both compounds showed a highly polarised and verapamile sensitive transport across monolayers of Caco-2 cells. The total brain-uptake of [{sup 3}H]2 was 6 times higher in mdr1a(-/-) knock-out mice lacking the gene encoding P-glycoprotein compared to wild type mice. Pretreatment of one monkey with Cyclosporin A (15 mg/kg) resulted in 40% higher brain uptake for [{sup 11}C]3 when compared with baseline. These observations support the view that efflux by P-glycoprotein can be of quantitative importance for the total brain-uptake of some PET radioligands.

  7. Saw palmetto extracts potently and noncompetitively inhibit human alpha1-adrenoceptors in vitro.

    Goepel, M; Hecker, U; Krege, S; Rübben, H; Michel, M C

    1999-02-15

    We wanted to test whether phytotherapeutic agents used in the treatment of lower urinary tract symptoms have alpha1-adrenoceptor antagonistic properties in vitro. Preparations of beta-sitosterol and extracts of stinging nettle, medicinal pumpkin, and saw palmetto were obtained from several pharmaceutical companies. They were tested for their ability to inhibit [3H]tamsulosin binding to human prostatic alpha1-adrenoceptors and [3H]prazosin binding to cloned human alpha1A- and alpha1B-adrenoceptors. Inhibition of phenylephrine-stimulated [3H]inositol phosphate formation by cloned receptors was also investigated. Up to the highest concentration which could be tested, preparations of beta-sitosterol, stinging nettle, and medicinal pumpkin were without consistent inhibitory effect in all assays. In contrast, all tested saw palmetto extracts inhibited radioligand binding to human alpha1-adrenoceptors and agonist-induced [3H]inositol phosphate formation. Saturation binding experiments in the presence of a single saw palmetto extract concentration indicated a noncompetitive antagonism. The relationship between active concentrations in vitro and recommended therapeutic doses for the saw palmetto extracts was slightly lower than that for several chemically defined alpha1-adrenoceptor antagonists. Saw palmetto extracts have alpha1-adrenoceptor-inhibitory properties. If bioavailability and other pharmacokinetic properties of these ingredients are similar to those of the chemically defined alpha1-adrenoceptor antagonists, alpha1-adrenoceptor antagonism might be involved in the therapeutic effects of these extracts in patients with lower urinary tract symptoms suggestive of benign prostatic obstruction.

  8. Inhibition of human prostate cancer cells proliferation by a selective alpha1-adrenoceptor antagonist labedipinedilol-A involves cell cycle arrest and apoptosis

    Liou, S.-F.; Lin, H.-H.; Liang, J.-C.; Chen, I.-J.; Yeh, J.-L.

    2009-01-01

    In this research, we conducted an in vitro analysis to evaluate the prostate cancer cells response to labedipinedilol-A in order to determine the effect of this selective α 1 -adrenoceptor antagonist to suppress prostate cancer cell growth by affecting cell proliferation and apoptosis. Here, we report that treatment of androgen-sensitive (LNCaP) and androgen-insensitive (PC-3) prostate cancer cells with labedipinedilol-A inhibited cell proliferation in concentration-dependent and time-dependent manners. Moreover, norepinephrine-stimulated proliferation of both cell lines are markedly inhibited by labedipinedilol-A. The probable involvement of α 1 -adrenoceptors in this cellular response is suggested. Labedipinedilol-A-induced growth inhibition was associated with G 0 /G 1 arrest, and G 2 /M arrest depending upon concentrations. Cell cycle blockade was associated with reduced amounts of cyclin D1/2, cyclin E, Cdk2, Cdk4, and Cdk6 and increased levels of the Cdk inhibitory proteins (Cip1/p21 and Kip1/p27). In addition, labedipinedilol-A also induced apoptosis in PC-3 cells, as determined by using Hoechst 33342 staining, DNA fragmentation, and Annexin V staining assay. Furthermore, labedipinedilol-A triggered the mitochondrial apoptotic pathway, as indicated by increasing the expression of Bax, but decreasing the level of Bcl-2, resulting in mitochondrial membrane potential loss, cytochrome c release, and activation of caspase-9 and -3. We further investigated the role of MAPK cascades in the anti-proliferative and apoptosis effects of labedipinedilol-A, and confirmed that labedipinedilol-A could activate JNK1/2 but not p38 in both cell lines. Unlike JNK1/2, however, labedipinedilol-A treatment resulted in down-regulation of phospho-ERK1/2 expression. We concluded that labedipinedilol-A possessed the growth-suppressive and apoptotic effects on LNCaP and PC-3 cells by its α 1 -adrenoceptor blockade, and the apoptotic effects of labedipinedilol-A primarily through

  9. Do saw palmetto extracts block human alpha1-adrenoceptor subtypes in vivo?

    Goepel, M; Dinh, L; Mitchell, A; Schäfers, R F; Rübben, H; Michel, M C

    2001-02-15

    To test whether saw palmetto extracts, which act as alpha1-adrenoceptor antagonists in vitro, also do so in vivo in man. In a placebo-controlled, double-blind, four-way cross-over study 12 healthy young men were treated with three different saw palmetto extract preparations (320 mg o.d.) for 8 days each. On the last day, before and 2, 4 and 6 hr after drug intake blood pressure and heart rate were determined and blood samples obtained, which were used in an ex vivo radioreceptor assay with cloned human alpha1-adrenoceptor subtypes. Saw palmetto extract treatment did not result in alpha1-adrenoceptor subtype occupancy in the radioreceptor assay. Although the saw palmetto extracts caused minor reductions of supine blood pressure, they did not affect blood pressure during orthostatic stress testing and did not alter heart rate under either condition. Moreover, plasma catecholamines remained largely unaltered. Despite their alpha1-adrenoceptor antagonist effects in vitro, therapeutically used doses of saw palmetto extracts do not cause alpha1-adrenoceptor antagonism in man in vivo. Copyright 2001 Wiley-Liss, Inc.

  10. Saw palmetto extracts potently and noncompetitively inhibit human alpha1-adrenoceptors in vitro

    Goepel, M.; Hecker, U.; Krege, S.; Rübben, H.; Michel, M. C.

    1999-01-01

    BACKGROUND: We wanted to test whether phytotherapeutic agents used in the treatment of lower urinary tract symptoms have alpha1-adrenoceptor antagonistic properties in vitro. METHODS: Preparations of beta-sitosterol and extracts of stinging nettle, medicinal pumpkin, and saw palmetto were obtained

  11. Murine alpha1-adrenoceptor subtypes. I. Radioligand binding studies

    Yang, M.; Reese, J.; Cotecchia, S.; Michel, M. C.

    1998-01-01

    Alpha1-adrenoceptors were identified in murine tissues by [3H]prazosin saturation binding studies, with a rank order of cerebral cortex > cerebellum > liver > lung > kidney > heart > spleen, with the spleen not exhibiting detectable expression. Competition binding studies were performed with

  12. Effects of tamsulosin metabolites at alpha-1 adrenoceptor subtypes

    Taguchi, K.; Saitoh, M.; Sato, S.; Asano, M.; Michel, M. C.

    1997-01-01

    We have investigated the affinity and selectivity of tamsulosin and its metabolites, M1, M2, M3, M4 and AM1, at the tissue and the cloned alpha-1 adrenoceptor subtypes in the radioligand binding and the functional studies. In the radioligand binding studies, the compounds competed for [3H]prazosin

  13. [125Iodo]BE 2254, a new radioligand for alpha 1-adrenoceptors

    Engel, G.; Hoyer, D.

    1982-01-01

    [ 125 cIodo]2-[beta-(14-hydroxyphenyl)-ethyl-aminomethyl]-tetralone([ 125 Iodo]BE 2254 or IBE 2254), a new iodinated radioligand of high specific radioactivity (2175 Ci/mmol), was synthesized and used to characterize alpha 1-adrenoceptors in rat lung and cerebral cortex membranes. The binding constants of IBE 2254, using rat lung and cortex membranes, were Kd . 53 +/- 10 pM, Bmax . 53 +/- 8 fmol/mg; and Kd . 78 +/- 14 pM, Bmas . 210 +/- 26 fmol/mg, respectively (Kd . dissociation constant of IBE 2254 determined in saturation experiments). In equilibrium binding experiments with IBE 2254, at concentrations of the free ligand up to 1.2 nM, only one class of binding sites could be detected. In kinetic experiments, the association and dissociation rate constants were 2.3 X 10(9) M-1 min-1 and 0.10 min-1, respectively. In rat cerebral cortex membranes, alpha-adrenoceptor antagonists competed for IBE 2254 binding in the following order: prazosin greater than BE 2254 greater than WB 4101 greater than phentolamine greater than corynanthine greater than yohimbine greater than rauwolscine, indicating strongly that IBE 2254 binds to alpha 1-adrenoceptors. The calculated affinities of different alpha-adrenoceptor blocking agents from inhibition of IBE 2254 binding were nearly identical in rat lung and cerebral cortex. The low dissociation constant of the ligand together with its high specific radioactivity allows binding studies to be carried out with tissue samples where only small densities of alpha 1-adrenoceptors are present

  14. Radiosynthesis and evaluation of new α1-adrenoceptor antagonists as PET radioligands for brain imaging

    Airaksinen, Anu J.; Finnema, Sjoerd J.; Balle, Thomas; Varnäs, Katarina; Bang-Andersen, Benny; Gulyás, Balázs; Farde, Lars; Halldin, Christer

    2013-01-01

    Introduction: Evaluation of the α 1 -adrenoceptors in relation to brain pathophysiology and drug treatment has been hindered by lack of α 1 -adrenoceptor specific radioligands with sufficient brain exposure. Our aim was to develop an α 1 -adrenoceptor specific PET radioligand for brain imaging. Methods: Two sertindole analogues 1-(4-fluorophenyl)-5-(1-methyl-1H-1,2,4-triazol-3-yl)-3-(1-[ 11 C] methylpiperidin-4-yl)-1H-indole [ 11 C]3 and 1-(4-fluorophenyl)-3-(1-[ 11 C]methylpiperidin-4-yl)-5-(pyrimidin-5-yl) -1H-indole ([ 11 C]Lu AA27122) [ 11 C]4 were synthesized and evaluated as α 1 -adrenoceptor PET radioligands in cynomolgus monkey. Compounds 3 and 4 were selected due to their promising in vitro preclinical profile; high affinity and selectivity for the α 1 -adrenoceptor, favourable blood brain barrier permeability rates in Caco-2 monolayers and promising brain tissue/plasma ratio, assessed by equilibrium dialysis of free fraction in plasma and brain homogenate. Results: Compounds [ 11 C]3 and [ 11 C]4 were synthesized from their desmethyl piperidine precursors with high specific radioactivity (> 370 GBq/μmol) using [ 11 C]methyl iodide. The 1,2,4-triazole analogue [ 11 C]3 exhibited poor brain uptake, but the corresponding pyrimidyl analogue [ 11 C]4 exhibited high brain exposure and binding in α 1 -adrenoceptor rich brain regions. However, the binding could not be inhibited by pretreatment with prazosin (0.1 mg/kg and 0.3 mg/kg). The results were extended by autoradiography of [ 11 C]4 binding in human brain sections and competition with antagonists from different structural families, revealing that only a minor portion of the observed binding of [ 11 C]4 in brain was α 1 -adrenoceptor specific. Conclusion: Though [ 11 C]3 and [ 11 C]4 proved not suitable as PET radioligands, the study provided further understanding of structural features influencing brain exposure of the chemical class of compounds related to the antipsychotic drug sertindole. It

  15. Radiolabelling and PET brain imaging of the α1-adrenoceptor antagonist Lu AE43936

    Risgaard, Rune; Ettrup, Anders; Balle, Thomas; Dyssegaard, Agnete; Hansen, Hanne Demant; Lehel, Szabolcs; Madsen, Jacob; Pedersen, Henrik; Püschl, Ask; Badolo, Lassina; Bang-Andersen, Benny; Knudsen, Gitte Moos; Kristensen, Jesper Langgaard

    2013-01-01

    Cerebral α 1 -adrenoceptors are a common target for many antipsychotic drugs. Thus, access to positron emission tomography (PET) brain imaging of α 1 -adrenoceptors could make important contributions to the understanding of psychotic disorders as well as to the pharmacokinetics and occupancy of drugs targeting the α 1 -adrenoceptors. However, so far no suitable PET radioligand has been developed for brain imaging of α 1 -adrenoceptors. Here, we report the synthesis of both enantiomers of the desmethyl precursors of the high affinity α 1 -adrenoceptor ligand Lu AE43936 (). The two enantiomers of were subsequently [ 11 C] radiolabelled and evaluated for brain uptake and binding by PET imaging in Danish Landrace pigs. (S)-[ 11 C]- and (R)-[ 11 C]- showed very limited brain uptake. Pre-treatment with cyclosporine A (CsA) resulted in a large increase in brain uptake, indicating that (R)-[ 11 C]- is a substrate for active efflux-transporters. This was confirmed in Madin Darby canine kidney (MDCK) cells overexpressing permeability glycoprotein (Pgp). In conclusion, the limited brain uptake of both (S)-[ 11 C]- and (R)-[ 11 C]- in the pig brain necessitates the search for alternative radioligands for in vivo PET brain imaging of α 1 -adrenoceptors.

  16. In vivo binding in rat brain and radiopharmaceutical preparation of radioiodinated HEAT, an alpha-1 adrenoceptor ligand

    Couch, M.W.; Greer, D.M.; Thonoor, C.M.; Williams, C.M.

    1988-01-01

    In vivo binding of [ 125 I]-2-[beta-(3-iodo-4-hydroxyphenyl)ethylaminomethyl tetralone) ([ 125 I]HEAT) to alpha-1 adrenoceptors in the rat brain was determined over 4 hr. Uptake in the thalamus and frontal cortex was approximately 0.1% injected dose per gram tissue. Thalamus/cerebellum ratios of 10:1 and frontal cortex/cerebellum ratios of 5:1 were found at 4 hr. Pretreatment with prazosin, an alpha-1 antagonist, completely inhibited the accumulation of [ 125 I]HEAT in thalamus and frontal cortex; yet uptake of radioactivity was not significantly affected by antagonists and agonists for other receptors classes (propranolol, beta-1; apomorphine, D-1; spiperone, D-2). Binding of [ 125 I]HEAT is saturable. At 4 hr, [ 125 I]HEAT or [ 123 I]HEAT was shown to be the only radioactive material in rat thalamus and frontal cortex. Iodine-123 HEAT and [ 125 I]HEAT were synthesized as radiopharmaceuticals within 3 hr in 99% radiochemical purity

  17. Alpha-1 adrenoceptors in brown adipose tissue of lean and ob/ob mice

    Behrens-Zaror, G.; Himms-Hagen, J.

    1986-01-01

    Obese (ob/ob) mice have a low capacity to increase thyroxine 5'-deiodinase (T4 5'-D) in brown adipose tissue (BAT) when exposed to cold. This effect is mediated by alpha-1 (A-1) adrenoceptors. The authors objective was to find out whether BAT of the ob/ob mouse has normal A-1 receptors. Saturation analysis of binding of [3H]-WB4101 at 0.05 nM to 10 μM to crude membrane preparations (100,000 g pellets from Polytron homogenates) using the LIGAND program of Munson and Rodbard, showed two populations of binding sites in BAT of lean (+/+, 11-15 wk old) mice. Acute exposure (12 h, 14 0 C) or acclimation to cold (3 wk, 14 0 C) did not alter affinity or concentration of sites. Displacement with yohimbine and prazosin indicated binding of WB4101 to A-1 receptors. Very young (5 wk) lean (+/.) and obese mice had similar affinity constants (lean 0.13 +/- 0.043 and 34.2 +/- 14.9; obese, 0.12 +/- 0.028 and 20.9 +/- 5.48 nM) and concentrations (lean 22.4 +/- 3.8 and 647 +/- 137; obese, 28.6 +/- 4.6 and 547 +/- 105 fmol/mg protein) of sites. Old (1 yr) mice had high affinity sites similar to those in younger animals (KD lean 0.19 +/- 0.028, obese, 0.25 +/- 0.075; Bmax lean, 60.2 +/- 12.1; obese, 63.1 +/- 13.5 fmol/mg protein). The authors conclude that the ob/ob mouse has normal high affinity A-1 receptors in BAT. Anomalous properties of low affinity binding in old ob/ob mice could not be characterized because of high nonspecific binding. BAT of the ob/ob mouse does not lack A-1 receptors but may have a post-receptor alteration in the A-1 adrenoceptor-mediated response

  18. Dopamine D2 receptors and alpha1-adrenoceptors synergistically modulate locomotion and behavior of rats in a place avoidance task

    Stuchlík, Aleš; Petrásek, Tomáš; Valeš, Karel

    2008-01-01

    Roč. 189, č. 1 (2008), s. 139-144 ISSN 0166-4328 R&D Projects: GA ČR(CZ) GA309/07/0341; GA MZd(CZ) NR9178; GA MŠk(CZ) 1M0517; GA MŠk(CZ) LC554 Institutional research plan: CEZ:AV0Z50110509 Keywords : D2 receptors * alpha1-adrenoceptors * behavior Subject RIV: FH - Neurology Impact factor: 3.171, year: 2008

  19. Modulation of intracellular Ca2+ via L-type calcium channels in heart cells by the autoantibody directed against the second extracellular loop of the alpha1-adrenoceptors.

    Bkaily, Ghassan; El-Bizri, Nesrine; Bui, Michel; Sukarieh, Rami; Jacques, Danielle; Fu, Michael L X

    2003-03-01

    The effects of methoxamine, a selective alpha1-adrenergic receptor agonist, and the autoantibody directed against the second extracellular loop of alpha1-adrenoceptors were studied on intracellular free Ca2+ levels using confocal microscopy and ionic currents using the whole-cell patch clamp technique in single cells of 10-day-old embryonic chick and 20-week-old fetal human hearts. We observed that like methoxamine, the autoantibody directed against the second extracellular loop of alpha1-adrenoreceptors significantly increased the L-type calcium current (I(Ca(L))) but had no effect on the T-type calcium current (I(Ca(T))), the delayed outward potassium current, or the fast sodium current. This effect of the autoantibody was prevented by a prestimulation of the receptors with methoxamine and vice versa. Moreover, treating the cells with prazosin, a selective alpha1-adrenergic receptor antagonist blocked the methoxamine and the autoantibody-induced increase in I(Ca(L)), respectively. In absence of prazosin, both methoxamine and the autoantibody showed a substantial enhancement in the frequency of cell contraction and that of the concomitant cytosolic and nuclear free Ca2+ variations. The subsequent addition of nifedipine, a specific L-type Ca2+ channel blocker, reversed not only the methoxamine or the autoantibody-induced effect but also completely abolished cell contraction. These results demonstrated that functional alpha1-adrenoceptors exist in both 10-day-old embryonic chick and 20-week-old human fetal hearts and that the autoantibody directed against the second extracellular loop of this type of receptors plays an important role in stimulating their activity via activation of L-type calcium channels. This loop seems to have a functional significance by being the target of alpha1-receptor agonists like methoxamine.

  20. "Ejaculatory disorders and α1-adrenoceptor antagonists therapy: clinical and experimental researches"

    Lania Caterina

    2006-07-01

    Full Text Available Abstract Background It is well known that the use of the α-adrenergic receptor antagonists in the BPH therapy may induce ejaculatory disorder. A review of clinical literature shows a greater incidence of ejaculatory disorder during the use of tamsulosin compared with alfuzosin. Anejaculation has been until now referred to retrograde ejaculation due to relaxation of prostatic and bladder neck smooth muscle tone. In a recent researches was evaluated the effect of tamsulosin and alfuzosin on rat vas deferent "in vitro", concluding that tamsulosin may "cause ejaculatory dysfunction by altering the progression and emission of sperm". An abnormal increase of contraction would be the cause of ejaculatory disorder. The aim of our paper is to compare human and rat vas deferens contractile activity and to evaluate with a clinical study if tamsulosin causes retrograde ejaculation disorder. Methods We have revaluated the human and rat vas deferens contractile activity in vitro according to our experience and literature. We have also performed a clinical study on 10 patients (48–72 y affected by anejaculation. Post-coital urine was examined to search spermatozoa. Results Human and rat vas deferens activity is not comparable. Contractile activity induced by norepinephrin after tamsulosin incubation in rat prostatic vas deferens strips is similar to the contractile activity evoked by norepinephrin in human strips. Spermatozoa were found in post coital urine of 6 patients. Conclusion In our opinion the treatment with tamsulosin may induce retrograde ejaculation but not other ejaculatory disorder due to abnormal sperm progression.

  1. Influence of the low thyroid state in diabetes mellitus on cardiac function and inotropic responsiveness to alpha 1-adrenoceptor stimulation: comparison with the role of hypothyroidism alone.

    Beenen, O H; Pfaffendorf, M; van Zwieten, P A

    1996-10-01

    The hypothyroid state accompanying diabetes mellitus has been suggested to be partly responsible for the diabetes-induced metabolic, hemodynamic, and pharmacological cardiovascular changes. We assessed the effectivity of streptozotocin (STZ) to induce diabetes mellitus and a hypothyroid state. Furthermore, we investigated the influence of diabetes and hypothyrodism on cardiac function and the inotropic responsiveness to the alpha 1-adrenoceptor agonist cirazoline in isolated perfused hearts. Fasted or nonfasted Wistar rats were made diabetic with STZ 20, 40 or 60 mg/kg intravenously (i.v.). Another group was made hypothyroid by addition of 6-n-propyl-2-thiouracil (PTU) to their drinking water. Rats receiving PTU became hypothyroid, whereas rats receiving STZ became simultaneously diabetic and hypothyroid. Basal functional parameters obtained in isolated perfused hearts were not influenced by diabetes, whereas maximal contractility was reduced in hearts obtained from hypothyroid animals. Cardiac inotropic responses to cirazoline were increased in diabetic rats, whereas responses in hypothyroid rats were not different from those in hearts obtained from control animals. Although diabetes mellitus and hypothyroidism are associated with various similar metabolic and haemodynamic parameters, the increased inotropic response to alpha 1-adrenoceptor stimulation as observed in isolated perfused hearts of diabetic rats cannot be explained by the decrease in serum thyroxine levels.

  2. The cytotoxicity of the α1-adrenoceptor antagonist prazosin is linked to an endocytotic mechanism equivalent to transport-P

    Fuchs, Robert; Stracke, Anika; Ebner, Nadine; Zeller, Christian Wolfgang; Raninger, Anna Maria; Schittmayer, Matthias; Kueznik, Tatjana; Absenger-Novak, Markus; Birner-Gruenberger, Ruth

    2015-01-01

    Since the α1-adrenergic antagonist prazosin (PRZ) was introduced into medicine as a treatment for hypertension and benign prostate hyperplasia, several studies have shown that PRZ induces apoptosis in various cell types and interferes with endocytotic trafficking. Because PRZ is also able to induce apoptosis in malignant cells, its cytotoxicity is a focus of interest in cancer research. Besides inducing apoptosis, PRZ was shown to serve as a substrate for an amine uptake mechanism originally discovered in neurones called transport-P. In line with our hypothesis that transport-P is an endocytotic mechanism also present in non-neuronal tissue and linked to the cytotoxicity of PRZ, we tested the uptake of QAPB, a fluorescent derivative of PRZ, in cancer cell lines in the presence of inhibitors of transport-P and endocytosis. Early endosomes and lysosomes were visualised by expression of RAB5-RFP and LAMP1-RFP, respectively; growth and viability of cells in the presence of PRZ and uptake inhibitors were also tested. Cancer cells showed co-localisation of QAPB with RAB5 and LAMP1 positive vesicles as well as tubulation of lysosomes. The uptake of QAPB was sensitive to transport-P inhibitors bafilomycin A1 (inhibits v-ATPase) and the antidepressant desipramine. Endocytosis inhibitors pitstop ® 2 (general inhibitor of endocytosis), dynasore (dynamin inhibitor) and methyl-β-cyclodextrin (cholesterol chelator) inhibited the uptake of QAPB. Bafilomycin A1 and methyl-β-cyclodextrin but not desipramine were able to preserve growth and viability of cells in the presence of PRZ. In summary, we confirmed the hypothesis that the cellular uptake of QAPB/PRZ represents an endocytotic mechanism equivalent to transport-P. Endocytosis of QAPB/PRZ depends on a proton gradient, dynamin and cholesterol, and results in reorganisation of the LAMP1 positive endolysosomal system. Finally, the link seen between the cellular uptake of PRZ and cell death implies a still unknown pro

  3. Does alpha 1-acid glycoprotein act as a non-functional receptor for alpha 1-adrenergic antagonists?

    Qin, M; Oie, S

    1994-11-01

    The ability of a variety of alpha 1-acid glycoproteins (AAG) to affect the intrinsic activity of the alpha 1-adrenergic antagonist prazosin was studied in rabbit aortic strip preparations. From these studies, the activity of AAG appears to be linked to their ability to bind the antagonist. However, a capability to bind prazosin was not the only requirement for this effect. The removal of sialic acid and partial removal of the galactose and mannose residues by periodate oxidation of human AAG all but eliminated the ability of AAG to affect the intrinsic pharmacologic activity of prazosin, although the binding of prazosin was not significantly affected. The presence of bovine AAG, a protein that has a low ability to bind prazosin, reduced the effect of human AAG on prazosin activity. Based upon these results, we propose that AAG is able to bind in the vicinity of the alpha 1-adrenoceptors, therefore extending the binding region for antagonists in such a way as to decrease the ability of the antagonist to interact with the receptor. The carbohydrate side-chains are important for the binding of AAG in the region of the adrenoceptor.

  4. Relaxation Responses of Trigonal Smooth Muscle from Rabbit by Alpha1-Adrenoceptor Antagonists Alfuzosin, Doxazosin and Tamsulosin

    A. Karadeniz

    2008-01-01

    Full Text Available This study was performed to investigate the effects of alfuzosin, doxazosin and tamsulosin in vitro on trigone smooth muscle of rabbit. In this study, fifteen rabbits weighing 2.5 - 3 kg were used. One strip in the shape of a trigone was prepared for each of the isolated bladders. Firstly, an initial tension of 1 g was placed on each segment, and we waited for equilibration by constantly bubbling with 95% O2 and 5% CO2. Next, the determination level of electrical stimulation which created submaximal contraction and effective dosage were found for trigone and they were determined by applying different concentrations of phenylephrine (10-8 M, 10-7 M, 10-6 M, 10-5 M, respectively. Firstly 10-8 M dosage of alfuzosin (10-8 M, 10-7 M, 10-6 M, 10-5 M was added, then we waited for 20 min. Then, an effective dosage of phenylephrine (10-5 M was added into the solution and we waited for 7 min again. After this process, electrical stimulation was applied for the contraction of the tissue. After stimulation, the tissue was washed twice every two minutes and rested; we waited until the tissue reached its starting stretching value. The same processes were performed for the other dosages of alfuzosin (10-7 M, 10-6 M, 10-5 M, doxazosin (10-7 M, 10-6 M, 10-5 M and tamsulosin (10-7 M, 10-6 M, 10-5 M, respectively. In conclusion, when we compared the amplitudes of the responses of all concentrations of doxazosin, alfuzosin and tamsulosin in the trigone smooth muscle with amplitude of a response of effective concentration of phenylephrine, it was determined that the prevention level of contractions occurred after tamsulosin hydrochloride was higher than after alfuzosin hydrochloride and doxazosin mesylate. With these results, we showed that alfuzosin, doxazosin and tamsulosin inhibited noradrenalin-based contractions in the rabbit trigone smooth muscle and this result can be used both for in vitro and in vivo future studies.

  5. Alpha-Adrenoceptor Antagonists Improve Memory by Activating -methyl-D-Aspartate-Induced Ion Currents in the Rat Hippocampus

    Chang Hee Kim

    2015-12-01

    Full Text Available Purpose: Alpha1 (α1-adrenoceptor antagonists are widely used to treat lower urinary tract symptoms. These drugs not only act on peripheral tissues, but also cross the blood-brain barrier and affect the central nervous system. Therefore, α1-adrenoceptor antagonists may enhance brain functions. In the present study, we investigated the effects of tamsulosin, an α1-adrenoceptor antagonist, on short-term memory, as well as spatial learning and memory, in rats. Methods: The step-down avoidance test was used to evaluate short-term memory, and an eight-arm radial maze test was used to evaluate spatial learning and memory. TUNEL (terminal deoxynucleotidyltransferase-mediated dUTP nick end labeling staining was performed in order to evaluate the effect of tamsulosin on apoptosis in the hippocampal dentate gyrus. Patch clamp recordings were used to evaluate the effect of tamsulosin on ionotropic glutamate receptors, such as N-methyl-D-aspartate (NMDA, amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA, and kainate receptors, in hippocampal CA1 neurons. Results: Tamsulosin treatment improved short-term memory, as well as spatial learning and memory, without altering apoptosis. The amplitudes of NMDA-induced ion currents were dose-dependently increased by tamsulosin. However, the amplitudes of AMPA- and kainate-induced ion currents were not affected by tamsulosin. Conclusions: Tamsulosin enhanced memory function by activating NMDA receptor-mediated ion currents in the hippocampus without initiating apoptosis. The present study suggests the possibility of using tamsulosin to enhance memory under normal conditions, in addition to its use in treating overactive bladder.

  6. Tesofensine, a novel triple monoamine reuptake inhibitor, induces appetite suppression by indirect stimulation of alpha1 adrenoceptor and dopamine D1 receptor pathways in the diet-induced obese rat

    Axel, Anne Marie Dixen; Mikkelsen, Jens D; Hansen, Henrik H

    2010-01-01

    ) and partially antagonized by co-administration of SCH23390 (0.03 mg/kg, DA D(1) receptor antagonist). In contrast, tesofensine-induced hypophagia was not affected by RX821002 (0.3 mg/kg, alpha(2) adrenoceptor antagonist), haloperidol (0.03 mg/kg, D(2) receptor antagonist), NGB2904 (0.1 mg/kg, D(3) receptor...

  7. Adverse cutaneous reactions induced by TNF-alpha antagonist therapy.

    Borrás-Blasco, Joaquín; Navarro-Ruiz, Andrés; Borrás, Consuelo; Casterá, Elvira

    2009-11-01

    To review adverse cutaneous drug reactions induced by tumor necrosis factor alpha (TNF-alpha) antagonist therapy. A literature search was performed using PubMed (1996-March 2009), EMBASE, and selected MEDLINE Ovid bibliography searches. All language clinical trial data, case reports, letters, and review articles identified from the data sources were used. Since the introduction of TNF-alpha antagonist, the incidence of adverse cutaneous drug reactions has increased significantly. A wide range of different skin lesions might occur during TNF-alpha antagonist treatment. New onset or exacerbation of psoriasis has been reported in patients treated with TNF-alpha antagonists for a variety of rheumatologic conditions. TNF-alpha antagonist therapy has been associated with a lupus-like syndrome; most of these case reports occurred in patients receiving either etanercept or infliximab. Serious skin reactions such as erythema multiforme, Stevens-Johnson syndrome, and toxic epidermal necrolysis have been reported rarely with the use of TNF-alpha antagonists. As the use of TNF-alpha antagonists continues to increase, the diagnosis and management of cutaneous side effects will become an increasingly important challenge. In patients receiving TNF-alpha antagonist treatment, skin disease should be considered, and clinicians need to be aware of the adverse reactions of these drugs.

  8. Characterizations of the α1-adrenoceptor subtypes mediating contractions of the human internal anal sphincter.

    Owaki, Hiroyuki; Sadahiro, Sotaro; Takaki, Miyako

    2015-04-01

    Human internal anal sphincter (IAS) is contracted by α1-adrenoceptor stimulation and thus α1-adrenoceptor agonists may be useful in treating fecal incontinence. This study characterizes the contribution of α1-adrenoceptor subtypes in contraction of human IAS and to investigate the age-related risk of patients with fecal incontinence. IAS and inferior mesenteric artery (IMA), as a predictor of systemic arterial pressure, were obtained from 11 patients. Both muscle strips were assessed by isometric-contraction experiments using phenylephrine, further in IAS, in the presence of various subtype selective α1-adrenoceptor antagonists. Immunohistochemistry and gene expression studies were performed in the same samples. The mean pEC50 values with SEM of phenylephrine in IAS (6.30 ± 0.13) were higher than those of IMA (5.60 ± 0.10). Furthermore, the age-related pEC50 change of IAS was observed between age IAS, rightward shift of the concentration-response curves of phenylephrine was observed with three α1-adrenoceptor antagonists. Each pKB value of silodosin, BMY-7378 and prazosin was 9.36 ± 0.53, 7.28 ± 0.20 and 8.89 ± 0.12, respectively. These pKB values and gene expression studies indicated that α1A-adrenoceptor subtypes predominantly contributed to human IAS contraction. Copyright © 2015 The Authors. Production and hosting by Elsevier B.V. All rights reserved.

  9. β1-Adrenoceptor blocker aggravated ventricular arrhythmia.

    Wang, Yan; Patel, Dimpi; Wang, Dao Wu; Yan, Jiang Tao; Hsia, Henry H; Liu, Hao; Zhao, Chun Xia; Zuo, Hou Juan; Wang, Dao Wen

    2013-11-01

    To assess the impact of β1 -adrenoceptor blockers (β1 -blocker) and isoprenaline on the incidence of idiopathic repetitive ventricular arrhythmia that apparently decreases with preprocedural anxiety. From January 2010 to July 2012, six patients were identified who had idiopathic ventricular arrhythmias that apparently decreased (by greater than 90%) with preprocedural anxiety. The number of ectopic ventricular beats per hour (VPH) was calculated from Holter or telemetry monitoring to assess the ectopic burden. The mean VPH of 24 hours from Holter before admission (VPH-m) was used as baseline (100%) for normalization. β1 -Blockers, isoprenaline, and/or aminophylline were administrated successively on the ward and catheter lab to evaluate their effects on the ventricular arrhythmias. Among 97 consecutive patients with idiopathic ventricular arrhythmias, six had reduction in normalized VPHs in the hour before the scheduled procedure time from (104.6 ± 4.6%) to (2.8 ± 1.6%) possibly due to preprocedural anxiety (P < 0.05), then increased to (97.9 ± 9.7%) during β1 -blocker administration (P < 0.05), then quickly reduced to (1.6 ± 1.0%) during subsequent isoprenaline infusion. Repeated β1 -blocker quickly counteracted the inhibitory effect of isoprenaline, and VPHs increased to (120.9 ± 2.4%) from (1.6 ± 1.0%; P < 0.05). Isoprenaline and β1 -blocker showed similar effects on the arrhythmias in catheter lab. In some patients with structurally normal heart and ventricular arrhythmias there is a marked reduction of arrhythmias associated with preprocedural anxiety. These patients exhibit a reproducible sequence of β1 -blocker aggravation and catecholamine inhibition of ventricular arrhythmias, including both repetitive ventricular premature beats and monomorphic ventricular tachycardia. ©2013, The Authors. Journal compilation ©2013 Wiley Periodicals, Inc.

  10. Alpha antagonists and intraoperative floppy iris syndrome: A spectrum

    Sharif A Issa

    2008-07-01

    Full Text Available Sharif A Issa, Omar H Hadid, Oliver Baylis, Margaret DayanDepartment of Ophthalmology, Royal Victoria Infirmary, Newcastle upon Tyne, UKBackground: To determine occurrence of features of intraoperative floppy iris syndrome (IFIS during cataract surgery in patients taking systemic alpha-antagonists (AA.Methods: We prospectively studied patients on AA and who underwent phacoemulsification. The following were recorded: pupil diameter preoperatively, iris flaccidity, iris prolapse and peroperative miosis.Results: We studied 40 eyes of 31 subjects. Mean age was 78 years. Overall, 14 eyes (13 patients showed signs of IFIS: 9/13 (69% eyes of patients on tamsulosin, 1/18 (6% eyes in the doxazosin group, 2/2 prazosin patients, 1/4 eyes in the indoramin group, and 1/2 eyes in two patients on a combination of doxazosin and tamsulosin. Most cases (92% had only one or two signs of IFIS. Bilateral cataract surgery was undertaken in 9 patients but only one patient (on tamsulosin had features of IFIS in both eyes, while 4 patients (2 on tamsulosin and 2 on other AA showed signs of IFIS in one eye only, and 4 patients did not show IFIS in either eye.Conclusion: Most AA were associated with IFIS, but it tends to present as a spectrum of signs rather than full triad originally described. Tamsulosin was most likely to be associated with IFIS; however, its intake does not necessarily mean that IFIS will occur. For patients on AA, the behavior of the iris intraoperatively in one eye is a poor predictor of the other eye. Surgeons should anticipate the occurrence of IFIS in any patient on AA.Keywords: alpha blocker, alpha antagonist, cataract surgery, intraoperative floppy iris syndrome, tamsulosin.

  11. Xamoterol, a new selective beta-1-adrenoceptor partial agonist, in the treatment of postural hypotension

    Mehlsen, J; Trap-Jensen, J

    1986-01-01

    Three patients severely disabled from postural hypotension were treated with xamoterol, a selective beta-1-adrenoceptor antagonist with a high degree of partial agonist activity. Oral treatment (200 mg b.i.d.) was chosen on the basis of the effects of acute intravenous administration of xamoterol...... and pindolol, a non-selective beta-adrenoceptor antagonist with partial agonist activity. In these patients pindolol had a predominantly antagonist effect, whereas xamoterol had a predominantly agonist effect after intravenous administration. Oral treatment was carried out with placebo control in a single......, supine). During the placebo period (2 weeks) heart rate decreased to pretreatment levels and mean blood pressure was reduced by only 14 mmHg. The patients reported substantial improvement in their condition during active medication. Xamoterol seems to be a useful alternative in the treatment of postural...

  12. Human fat cell alpha-2 adrenoceptors. I. Functional exploration and pharmacological definition with selected alpha-2 agonists and antagonists

    Galitzky, J.; Mauriege, P.; Berlan, M.; Lafontan, M.

    1989-01-01

    This study was undertaken to investigate more fully the pharmacological characteristics of the human fat cell alpha-2 adrenoceptor. Biological assays were performed on intact isolated fat cells while radioligand binding studies were carried out with [ 3 H]yohimbine in membranes. These pharmacological studies brought: (1) a critical definition of the limits of the experimental conditions required for the exploration of alpha-2 adrenergic responsiveness on human fat cells and membranes; (2) an improvement in the pharmacological definition of the human fat cell postsynaptic alpha-2 adrenoceptor. Among alpha-2 agonists, UK-14,304 was the most potent and the relative order of potency was: UK-14,304 greater than p-aminoclonidine greater than clonidine = B-HT 920 greater than rilmenidine. For alpha-2 antagonists, the potency order was: yohimbine greater than idazoxan greater than SK ampersand F-86,466 much greater than benextramine; (3) a description of the impact of benextramine (irreversible alpha-1/alpha-2 antagonist) on human fat cell alpha-2 adrenergic receptors and on human fat cell function; the drug inactivates the alpha-2 adrenergic receptors with a minor impact on beta adrenergic receptors and without noticeable alterations of fat cell function as assessed by preservation of beta adrenergic and Al-adenosine receptor-mediated lipolytic responses; and (4) a definition of the relationship existing between alpha-2 adrenergic receptor occupancy, inhibition of adenylate cyclase activity and antilipolysis with full and partial agonists. The existence of a receptor reserve must be taken into account when evaluating alpha-2 adrenergic receptor distribution and regulation of human fat cells

  13. Infliximab TNF-alpha antagonist decreases intraabdominal adhesions

    Kurukahvecioglu, O.; Koksal, H.; Yazicioglu, O.; Kerem, M.; Taneri, F.; Gulbahar, O.; Erdem, O.; Engin, D.

    2007-01-01

    Objective was to evaluate the effect of infliximab on adhesion formation and its associated morbidity and complications. This study was performed in the Faculty of Medicine, Gaze University, Turkey between July 2005 and October 2005. Thirty-five rats were randomly divided into 4 groups. Laparotomy was performed in the Sham group (n=5), whereas cecal abrasion was carried out in all other groups. After cecal abrasion 0.9% sodium chloride was administered in the saline group (n=10), infliximab was administered to the study group (n=10) and nothing was administered to the last group (n=10). Adhesion formation was evaluated with macroscopic adhesion scoring systems. Peritoneal fluid samples and mesenteric lymph node biopsies were taken to rule out bacterial peritonitis. Blood and peritoneal irrigation fluids samples were taken to measure the Tumor necrosis factor-alpha (TNF-alpha) levels. Macroscopic adhesion scores showed fewer adhesions in the infliximab group. The infliximab group had significantly fewer adhesions than the abrasion control and saline groups. According to the histological findings, there were no statistically significant differences between the groups. Early blocking of the activity of TNF-alpha after cecal abrasion resulted in lower rates of adhesion formation, macroscopically. The TNF-alpha, a proinflammatory cytokine appears to be an important mediator for postoperative adhesion formation. (author)

  14. The 5-HT1A Receptor PET Radioligand 11C-CUMI-101 Has Significant Binding to α1-Adrenoceptors in Human Cerebellum, Limiting Its Use as a Reference Region.

    Shrestha, Stal S; Liow, Jeih-San; Jenko, Kimberly; Ikawa, Masamichi; Zoghbi, Sami S; Innis, Robert B

    2016-12-01

    Prazosin, a potent and selective α 1 -adrenoceptor antagonist, displaces 25% of 11 C-CUMI-101 ([O-methyl- 11 C]2-(4-(4-(2-methoxyphenyl)piperazin-1-yl)butyl)-4-methyl-1,2,4-triazine-3,5(2H,4H)dione) binding in monkey cerebellum. We sought to estimate the percentage contamination of 11 C-CUMI-101 binding to α 1 -adrenoceptors in human cerebellum under in vivo conditions. In vitro receptor-binding techniques were used to measure α 1 -adrenoceptor density and the affinity of CUMI-101 for these receptors in human, monkey, and rat cerebellum. Binding potential (maximum number of binding sites × affinity [(1/dissociation constant]) was determined using in vitro homogenate binding assays in human, monkey, and rat cerebellum. 3 H-prazosin was used to determine the maximum number of binding sites, as well as the dissociation constant of 3 H-prazosin and the inhibition constant of CUMI-101. α 1 -adrenoceptor density and the affinity of CUMI-101 for these receptors were similar across species. Cerebellar binding potentials were 3.7 for humans, 2.3 for monkeys, and 3.4 for rats. Reasoning by analogy, 25% of 11 C-CUMI-101 uptake in human cerebellum reflects binding to α 1 -adrenoceptors, suggesting that the cerebellum is of limited usefulness as a reference tissue for quantification in human studies. © 2016 by the Society of Nuclear Medicine and Molecular Imaging, Inc.

  15. Functional analysis of guinea pig β1-adrenoceptor.

    Tanaka, Yoshio; Takahashi, Hiromi; Shibata, Sayuri; Namiki, Kana; Kimura, Sadao; Koike, Katsuo; Kasuya, Yoshitoshi

    2011-12-01

    Although similarity of pharmacological responses to certain stimuli between guinea pigs and humans has been reported, this has been poorly defined by a molecular biological approach. In this study, we cloned the gene of guinea pig ?1-adrenoceptor (ADRB1). The deduced amino acid sequence of guinea pig ADRB1 (467-aa) showed 91% and 92% identity with the human and rat ADRB1 sequences, respectively. Using HEK293T cells expressing guinea pig, human and rat ADRB1s independently, we elucidated the functional characteristics of each ADRB1. The ligand-binding profiles and the concentration-response relationships for isoprenaline-induced cyclic adenosine monophosphate (cAMP) production were similar among the three ADRB1s. Isoprenaline also induced phosphorylation of extracellular-signal related kinases (ERK) through ADRB1s in a concentration-dependent manner. The minimum effective concentration of isoprenaline for phosphorylation of ERK, through guinea pig ADRB1 was the same as through human ADRB1, but markedly lower than that of through rat ADRB1. ERK phosphorylation through guinea pig ADRB1 was sensitive to pertussis toxin, a dominant-negative ras and PD98059, indicating that a G(i)-mediated pathway is involved in the ADRB1/ERK signaling loop. These results suggest that the G(i)-coupling efficacy of guinea pig and human ADRB1s may be higher than that of rat ADRB1.

  16. Lower lid entropion secondary to treatment with alpha-1a receptor antagonist: a case report

    Simcock Peter

    2010-03-01

    Full Text Available Abstract Introduction The use of alpha-1a receptor antagonists (tamsulosin is widely accepted in the treatment of benign prostatic hypertrophy (BPH. It has previously been implicated as a causative agent in intra-operative floppy iris syndrome due to its effects on the smooth muscle. We report a case of lower lid entropion that may be related to a patient commencing treatment of tamsulosin. Case presentation A 74-year-old Caucasian man was started on alpha 1-a receptor antagonist (Tamsulosin treatment for benign prostatic hypertrophy. Eight days later, he presented to the ophthalmology unit with a right lower lid entropion which was successfully treated surgically with a Weiss procedure. Conclusion We report a case of lower lid entropion that may be secondary to the recent use of an alpha-1a blocker (tamsulosin. This can be explained by considering the effect of autonomic blockade on alpha-1 receptors in the Muller's muscle on a patient that may already have an anatomical predisposition to entropion formation due to a further reduction in muscle tone.

  17. α1-Adrenoceptors in the hippocampal dentate gyrus involved in learning-dependent long-term potentiation during active-avoidance learning in rats.

    Lv, Jing; Zhan, Su-Yang; Li, Guang-Xie; Wang, Dan; Li, Ying-Shun; Jin, Qing-Hua

    2016-11-09

    The hippocampus is the key structure for learning and memory in mammals and long-term potentiation (LTP) is an important cellular mechanism responsible for learning and memory. The influences of norepinephrine (NE) on the modulation of learning and memory, as well as LTP, through β-adrenoceptors are well documented, whereas the role of α1-adrenoceptors in learning-dependent LTP is not yet clear. In the present study, we measured extracellular concentrations of NE in the hippocampal dentate gyrus (DG) region using an in-vivo brain microdialysis and high-performance liquid chromatography techniques during the acquisition and extinction of active-avoidance behavior in freely moving conscious rats. Next, the effects of prazosin (an antagonist of α1-adrenoceptor) and phenylephrine (an agonist of the α1-adrenoceptor) on amplitudes of field excitatory postsynaptic potential were measured in the DG region during the active-avoidance behavior. Our results showed that the extracellular concentration of NE in the DG was significantly increased during the acquisition of active-avoidance behavior and gradually returned to the baseline level following extinction training. A local microinjection of prazosin into the DG significantly accelerated the acquisition of the active-avoidance behavior, whereas a local microinjection of phenylephrine retarded the acquisition of the active-avoidance behavior. Furthermore, in all groups, the changes in field excitatory postsynaptic potential amplitude were accompanied by corresponding changes in active-avoidance behavior. Our results suggest that NE activation of α1-adrenoceptors in the hippocampal DG inhibits active-avoidance learning by modulation of synaptic efficiency in rats.

  18. Highly Potent, Water Soluble Benzimidazole Antagonist for Activated (alpha)4(beta)1 Integrin

    Carpenter, R D; Andrei, M; Lau, E Y; Lightstone, F C; Liu, R; Lam, K S; Kurth, M J

    2007-08-29

    The cell surface receptor {alpha}{sub 4}{beta}{sub 1} integrin, activated constitutively in lymphoma, can be targeted with the bisaryl urea peptidomimetic antagonist 1 (LLP2A). However, concerns on its preliminary pharmacokinetic (PK) profile provided an impetus to change the pharmacophore from a bisaryl urea to a 2-arylaminobenzimidazole moiety resulting in improved solubility while maintaining picomolar potency [5 (KLCA4); IC{sub 50} = 305 pM]. With exceptional solubility, this finding has potential for improving PK to help diagnose and treat lymphomas.

  19. Preliminary Molecular Dynamic Simulations of the Estrogen Receptor Alpha Ligand Binding Domain from Antagonist to Apo

    Adrian E. Roitberg

    2008-06-01

    Full Text Available Estrogen receptors (ER are known as nuclear receptors. They exist in the cytoplasm of human cells and serves as a DNA binding transcription factor that regulates gene expression. However the estrogen receptor also has additional functions independent of DNA binding. The human estrogen receptor comes in two forms, alpha and beta. This work focuses on the alpha form of the estrogen receptor. The ERα is found in breast cancer cells, ovarian stroma cells, endometrium, and the hypothalamus. It has been suggested that exposure to DDE, a metabolite of DDT, and other pesticides causes conformational changes in the estrogen receptor. Before examining these factors, this work examines the protein unfolding from the antagonist form found in the 3ERT PDB crystal structure. The 3ERT PDB crystal structure has the estrogen receptor bound to the cancer drug 4-hydroxytamoxifen. The 4-hydroxytamoxifen ligand was extracted before the simulation, resulting in new conformational freedom due to absence of van der Waals contacts between the ligand and the receptor. The conformational changes that result expose the binding clef of the co peptide beside Helix 12 of the receptor forming an apo conformation. Two key conformations in the loops at either end of the H12 are produced resulting in the antagonist to apo conformation transformation. The results were produced over a 42ns Molecular Dynamics simulation using the AMBER FF99SB force field.

  20. The alpha7 nicotinic acetylcholine receptor-selective antagonist, methyllycaconitine, partially protects against beta-amyloid1-42 toxicity in primary neuron-enriched cultures.

    Martin, Shelley E; de Fiebre, Nancy Ellen C; de Fiebre, Christopher M

    2004-10-01

    Studies have suggested that the neuroprotective actions of alpha7 nicotinic agonists arise from activation of receptors and not from the extensive desensitization which rapidly follows activation. Here, we report that the alpha7-selective nicotinic antagonist, methyllycaconitine (MLA), protects against beta-amyloid-induced neurotoxicity; whereas the alpha4beta2-selective antagonist, dihydro-beta-erythroidine, does not. These findings suggest that neuroprotective actions of alpha7-acting agents arise from receptor inhibition/desensitization and that alpha7 antagonists may be useful neuroprotective agents.

  1. Neuroprotective and memory-related actions of novel alpha-7 nicotinic agents with different mixed agonist/antagonist properties.

    Meyer, E M; Tay, E T; Zoltewicz, J A; Meyers, C; King, M A; Papke, R L; De Fiebre, C M

    1998-03-01

    The goals of this study were to develop compounds that were selective and highly efficacious agonists at alpha-7 receptors, while varying in antagonist activity; and to test the hypothesis that these compounds had memory-related and neuroprotective actions associated with both agonist and antagonist alpha-7 receptor activities. Three compounds were identified; E,E-3-(cinnamylidene)anabaseine (3-CA), E,E-3-(2-methoxycinnamylidene) anabaseine (2-MeOCA) and E,E-3-(4-methoxycinnamylidene) anabaseine (4-MeOCA) each displaced [125I]alpha-bungarotoxin binding from rat brain membranes and activated rat alpha-7 receptors in a Xenopus oocyte expression system fully efficaciously. The potency series for binding and receptor activation was 2-MeOCA > 4-MeOCA = 3-CA and 2-MeOCA = 3-CA > 4-MeOCA, respectively. No compound significantly activated oocyte-expressed alpha-4beta-2 receptors. Although each cinnamylidene-anabaseine caused a long-term inhibition of alpha-7 receptors, as measured by ACh-application 5 min later, this inhibition ranged considerably, from less than 20% (3-CA) to 90% (2-MeOCA) at an identical concentration (10 microM). These compounds improved passive avoidance behavior in nucleus basalis lesioned rats, with 2-MeOCA most potent in this respect. In contrast, only 3-CA was neuroprotective against neurite loss during nerve growth factor deprivation in differentiated rat pheochromocytoma (PC12) cells. Choline, an efficacious alpha-7 agonist without antagonist activity, was also protective in this model. These results suggest that the neurite-protective action of alpha-7 receptor agonists may be more sensitive to potential long-term antagonist properties than acute behavioral actions are.

  2. Genetically engineered bacteriophage delivers a tumor necrosis factor alpha antagonist coating on neural electrodes

    Kim, Young Jun; Nam, Chang-Hoon; Jin, Young-Hyun; Stieglitz, Thomas; Salieb-Beugelaar, Georgette B

    2014-01-01

    This paper reports a novel approach for the formation of anti-inflammatory surface coating on a neural electrode. The surface coating is realized using a recombinant f88 filamentous bacteriophage, which displays a short platinum binding motif and a tumor necrosis factor alpha antagonist (TNF-α antagonist) on p3 and p8 proteins, respectively. The recombinant bacteriophages are immobilized on the platinum surface by a simple dip coating process. The selective and stable immobilization of bacteriophages on a platinum electrode is confirmed by quartz crystal microbalance with dissipation monitoring, atomic force microscope and fluorescence microscope. From the in vitro cell viability test, the inflammatory cytokine (TNF-α) induced cell death was prevented by presenting recombinant bacteriophage coating, albeit with no significant cytotoxic effect. It is also observed that the bacteriophage coating does not have critical effects on the electrochemical properties such as impedance and charge storage capacities. Thus, this approach demonstrates a promising anti-apoptotic as well as anti-inflammatory surface coating for neural implant applications. (paper)

  3. Inhibition of [11C]mirtazapine binding by alpha2-adrenoceptor antagonists studied by positron emission tomography in living porcine brain

    Smith, Donald F; Dyve, Suzan; Minuzzi, Luciano

    2006-01-01

    Inhibition of [11C]mirtazapine binding by alpha2-adrenoceptor antagonists studied by positron emission tomography in living porcine brain......Inhibition of [11C]mirtazapine binding by alpha2-adrenoceptor antagonists studied by positron emission tomography in living porcine brain...

  4. Development of a radioiodinated ligand for characterising α1-adrenoceptors

    Adams, A.; Jarrott, B.

    1982-01-01

    Two α-adrenoceptor antagonists, phentolamine and 2-(β-(4-hydroxyphenyl)-ethylaminomethyl)-tetralone (BE 2254) which are phenolic derivatives were radioiodinated after chloramine-T oxidation of Na 125 I and the labelled material isolated by chromatography. 125 I-Phentolamine does not bind selectively to α-adrenoceptors in guinea pig brain whereas the 125 I-BE 2254 derivative binds rapidly, reversibly and with high affinity to these receptors with a K/sub d/ of 230 pM. At low concentrations of 125 I-BE 2254 ( 1 subclass of adrenoceptors. Binding measurements to kidney and smooth muscle membrane preparations indicate that 125 I-BE 2254 may also be a useful tool in the study of α-adrenoceptors in peripheral tissues. The high specific activity of 125 I-BE 2254 permits the use of minimal quantities of membrane material for receptor assay and ligand displacement measurements, e.g. 250 μg per assay tube, and this provides a significant advantage over the use of existing radioligands such as 3 H-prazosin which requires approx. 40 times as much tissue

  5. Preclinical evaluation of an 18F-labelled beta1-adrenoceptor selective radioligand based on ICI 89,406.

    Law, Marilyn P; Wagner, Stefan; Kopka, Klaus; Renner, Christiane; Pike, Victor W; Schober, Otmar; Schäfers, Michael

    2010-05-01

    Radioligand binding studies indicate a down-regulation of myocardial beta(1)-adrenoceptors (beta(1)-AR) in cardiac disease which may or may not be associated with a decrease in beta(2)-ARs. We have chosen ICI 89,406, a beta(1)-selective AR antagonist, as the lead structure to develop new beta(1)-AR radioligands for PET and have synthesised a fluoro-ethoxy derivative (F-ICI). (S)-N-[2-[3-(2-Cyano-phenoxy)-2-hydroxy-propylamino]-ethyl]-N'-[4-(2-[(18)F]fluoro-ethoxy)-phenyl]-urea ((S)-[(18)F]F-ICI) was synthesised. Myocardial uptake of radioactivity after intravenous injection of (S)-[(18)F]F-ICI into adult CD(1) mice or Wistar rats was assessed with positron emission tomography (PET) and postmortem dissection. Metabolism was assessed by high-performance liquid chromatography analysis of plasma and urine. The heart was visualised with PET after injection of (S)-[(18)F]F-ICI but neither unlabelled F-ICI nor propranolol (non-selective beta-AR antagonist) injected 15 min after (S)-[(18)F]F-ICI affected myocardial radioactivity. Ex vivo dissection demonstrated that predosing with propranolol or CGP 20712 (beta(1)-selective AR-antagonist) did not affect myocardial radioactivity. Radiometabolites rapidly appeared in plasma and both (S)-[(18)F]F-ICI and radiometabolites accumulated in urine. Myocardial uptake of (S)-[(18)F]F-ICI after intravenous injection was mainly at sites unrelated to beta(1)-ARs. (S)-[(18)F]F-ICI is not a suitable beta(1)-selective-AR radioligand for PET. (c) 2010 Elsevier Inc. All rights reserved.

  6. Preferential reduction of binding of 125I-iodopindolol to beta-1 adrenoceptors in the amygdala of rat after antidepressant treatments

    Ordway, G.A.; Gambarana, C.; Tejani-Butt, S.M.; Areso, P.; Hauptmann, M.; Frazer, A.

    1991-01-01

    This study utilized quantitative receptor autoradiography to examine the effects of repeated administration of antidepressants to rats on the binding of the beta adrenoceptor antagonist, 125 I-iodopindolol ( 125 I-IPIN) to either beta-1 or beta-2 adrenoceptors in various regions of brain. Antidepressants were selected to represent various chemical and pharmacological classes including tricyclic compounds (desipramine and protriptyline), monoamine oxidase inhibitors (clorgyline, phenelzine and tranylcypromine), atypical antidepressants (mianserin and trazodone) and selective inhibitors of the uptake of serotonin (citalopram and sertraline). Additionally, rats were treated with various psychotropic drugs that lack antidepressant efficacy (cocaine, deprenyl, diazepam and haloperidol). Repeated treatment of rats with desipramine, protriptyline, clorgyline, phenelzine, tranylcypromine or mianserin reduced the binding of 125 I-IPIN to beta-1 adrenoceptors in many brain areas. Only in the basolateral and lateral nuclei of the amygdala did all six of these antidepressants significantly reduce 125 I-IPIN binding to beta-1 adrenoceptors. In these amygdaloid nuclei, the magnitude of the reduction in the binding of 125 I-IPIN caused by each of these drugs was comparable to or greater than the reduction in binding produced in any other region of brain. Reductions of binding of 125 I-IPIN after antidepressant treatments were not consistently observed in the cortex, the area of brain examined most often in homogenate binding studies. Only the monoamine oxidase inhibitors caused reductions in the binding of 125 I-IPIN to beta-2 adrenoceptors, and this effect was generally localized to the amygdala and hypothalamus

  7. Amygdala, Anxiety and Alpha(1) Adrenoceptors: Investigations Utilizing a Rodent Model of Traumatic Stress

    2006-08-23

    the effect of a variety of different modifiers to the startle response, from drugs to environmental conditions . It has repeatedly been seen that...in rats. J. Neurosci. 1999;19: 8696-8703. Maren,S. Neurobiology of Pavlovian fear conditioning . Annu. Rev. Neurosci. 2001;24: 897-931. Marmar,CR...stress can result in post-traumatic stress disorder (PTSD) and other pathophysiological conditions . PTSD is characterized by a number of

  8. The three α1-adrenoceptor subtypes show different spatio-temporal mechanisms of internalization and ERK1/2 phosphorylation.

    Perez-Aso, M; Segura, V; Montó, F; Barettino, D; Noguera, M A; Milligan, G; D'Ocon, P

    2013-10-01

    We analyzed the kinetic and spatial patterns characterizing activation of the MAP kinases ERK 1 and 2 (ERK1/2) by the three α1-adrenoceptor (α1-AR) subtypes in HEK293 cells and the contribution of two different pathways to ERK1/2 phosphorylation: protein kinase C (PKC)-dependent ERK1/2 activation and internalization-dependent ERK1/2 activation. The different pathways of phenylephrine induced ERK phosphorylation were determined by western blot, using the PKC inhibitor Ro 31-8425, the receptor internalization inhibitor concanavalin A and the siRNA targeting β-arrestin 2. Receptor internalization properties were studied using CypHer5 technology and VSV-G epitope-tagged receptors. Activation of α1A- and α1B-ARs by phenylephrine elicited rapid ERK1/2 phosphorylation that was directed to the nucleus and inhibited by Ro 31-8425. Concomitant with phenylephrine induced receptor internalization α1A-AR, but not α1B-AR, produced a maintained and PKC-independent ERK phosphorylation, which was restricted to the cytosol and inhibited by β-arrestin 2 knockdown or concanavalin A treatment. α1D-AR displayed constitutive ERK phosphorylation, which was reduced by incubation with prazosin or the selective α1D antagonist BMY7378. Following activation by phenylephrine, α1D-AR elicited rapid, transient ERK1/2 phosphorylation that was restricted to the cytosol and not inhibited by Ro 31-8425. Internalization of the α1D-AR subtype was not observed via CypHer5 technology. The three α1-AR subtypes present different spatio-temporal patterns of receptor internalization, and only α1A-AR stimulation translates to a late, sustained ERK1/2 phosphorylation that is restricted to the cytosol and dependent on β-arrestin 2 mediated internalization. Copyright © 2013 Elsevier B.V. All rights reserved.

  9. Actions of alpha2 adrenoceptor ligands at alpha2A and 5-HT1A receptors: the antagonist, atipamezole, and the agonist, dexmedetomidine, are highly selective for alpha2A adrenoceptors.

    Newman-Tancredi, A; Nicolas, J P; Audinot, V; Gavaudan, S; Verrièle, L; Touzard, M; Chaput, C; Richard, N; Millan, M J

    1998-08-01

    This study examined the activity of chemically diverse alpha2 adrenoceptor ligands at recombinant human (h) and native rat (r) alpha2A adrenoceptors compared with 5-HT1A receptors. First, in competition binding experiments at h alpha2A and h5-HT1A receptors expressed in CHO cells, several compounds, including the antagonists 1-(2-pyrimidinyl)piperazine (1-PP), (+/-)-idazoxan, benalfocin (SKF 86466), yohimbine and RX 821,002, displayed preference for h alpha2A versus h5-HT1A receptors of only 1.4-, 3.6-, 4-, 10- and 11-fold, respectively (based on differences in pKi values). Clonidine, brimonidine (UK 14304), the benzopyrrolidine fluparoxan and the guanidines guanfacine and guanabenz exhibited intermediate selectivity (22- to 31-fold) for h alpha2A receptors. Only the antagonist atipamezole and the agonist dexmedetomidine (DMT) displayed high preference for alpha2 adrenoceptors (1290- and 91-fold, respectively). Second, the compounds were tested for their ability to induce h5-HT1A receptor-mediated G-protein activation, as indicated by the stimulation of [35S]GTPgammaS binding. All except atipamezole and RX 821,002 exhibited agonist activity, with potencies which correlated with their affinity for h5-HT1A receptors. Relative efficacies (Emax values) were 25-35% for guanabenz, guanfacine, WB 4101 and benalfocin, 50-65% for 1-PP, (+/-)-idazoxan and clonidine, and over 70% for fluparoxan, oxymetazoline and yohimbine (relative to 5-HT = 100%). Yohimbine-induced [35S]GTPgammaS binding was inhibited by the selective 5-HT1A receptor antagonist WAY 100,635. In contrast, RX 821,002 was the only ligand which exhibited antagonist activity at h5-HT1A receptors, inhibiting 5-HT-stimulated [35S]GTPgammaS binding. Atipamezole, which exhibited negligeable affinity for 5-HT1A receptors, was inactive. Third, the affinities for r alpha2A differed considerably from the affinities for h alpha2A receptors whereas the affinities for r5-HT1A differed much less from the affinities for h5-HT

  10. Design and synthesis of novel sulfonamide-containing bradykinin hB2 receptor antagonists. 1. Synthesis and SAR of alpha,alpha-dimethylglycine sulfonamides.

    Fattori, Daniela; Rossi, Cristina; Fincham, Christopher I; Berettoni, Marco; Calvani, Federico; Catrambone, Fernando; Felicetti, Patrizia; Gensini, Martina; Terracciano, Rosa; Altamura, Maria; Bressan, Alessandro; Giuliani, Sandro; Maggi, Carlo A; Meini, Stefania; Valenti, Claudio; Quartara, Laura

    2006-06-15

    We recently published the extensive in vivo pharmacological characterization of MEN 16132 (J. Pharmacol. Exp. Ther. 2005, 616-623; Eur. J. Pharmacol. 2005, 528, 7), a member of the sulfonamide-containing human B(2) receptor (hB(2)R) antagonists. Here we report, in detail, how this family of compounds was designed, synthesized, and optimized to provide a group of products with subnanomolar affinity for the hB(2)R and high in vivo potency after topical administration to the respiratory tract. The series was designed on the basis of indications from the X-ray structures of the key structural motifs A and B present in known antagonists and is characterized by the presence of an alpha,alpha-dialkyl amino acid. The first lead (17) of the series was submitted to extensive chemical work to elucidate the structural requirements to increase hB(2) receptor affinity and antagonist potency in bioassays expressing the human B(2) receptor (hB(2)R). The following structural features were selected: a 2,4-dimethylquinoline moiety and a piperazine linker acylated with a basic amino acid. The representative lead compound 68 inhibited the specific binding of [(3)H]BK to hB(2)R with a pKi of 9.4 and antagonized the BK-induced inositolphosphate (IP) accumulation in recombinant cell systems expressing the hB(2)R with a pA(2) of 9.1. Moreover, compound 68 when administered (300 nmol/kg) intratracheally in the anesthetized guinea pig, was able to significantly inhibit BK-induced bronchoconstriction for up to 120 min after its administration, while having a lower and shorter lasting effect on hypotension.

  11. A RNA antagonist of hypoxia-inducible factor-1alpha, EZN-2968, inhibits tumor cell growth

    Greenberger, Lee M; Horak, Ivan D; Filpula, David

    2008-01-01

    Hypoxia-inducible factor-1 (HIF-1) is a transcription factor that plays a critical role in angiogenesis, survival, metastasis, drug resistance, and glucose metabolism. Elevated expression of the alpha-subunit of HIF-1 (HIF-1alpha), which occurs in response to hypoxia or activation of growth facto...

  12. Effects of tumor necrosis factor alpha antagonist, platelet activating factor antagonist, and nitric oxide synthase inhibitor on experimental otitis media with effusion.

    Kim, Dong-Hyun; Park, Yong-Soo; Jeon, Eun-Ju; Yeo, Sang-Won; Chang, Ki-Hong; Lee, Seung Kyun

    2006-08-01

    We studied the inflammatory responses in otitis media with effusion induced by lipopolysaccharide (LPS) in rats, and compared the preventive effects of tumor necrosis factor (TNF) soluble receptor type I (sTNFRI, a TNF-alpha antagonist), platelet activating factor antagonist, and the nitric oxide synthase inhibitor N(G)-nitro-L-arginine methyl ester (L-NAME). We used 2 control groups of Sprague Dawley rats (untreated and saline-treated) and 4 experimental groups, which all received an intratympanic injection of LPS, followed in 3 groups by experimental treatment of the same ear. The LPS group had no additional treatment. The L-NAME group received intraperitoneal injection of L-NAME and was reinjected after 12 hours. The A-85783 group was first given an intraperitoneal injection of A-85783. The sTNFRI group was first given an intratympanic injection of sTNFRI. Twenty-four hours after the initial intratympanic injection of LPS, temporal bones from each group were examined histopathologically and the vascular permeability of the middle ear mucosa was measured by Evans blue vital dye staining. The L-NAME, A-85783, and sTNFRI groups showed significantly reduced capillary permeability, subepithelial edema, and infiltration of inflammatory cells in comparison with the LPS group. There were no differences in capillary permeability, subepithelial edema, or infiltration of inflammatory cells between the A-85783 and sTNFRI groups. The L-NAME group showed no difference in vascular permeability or subepithelial edema in comparison with the A-85783 and sTNFRI groups, but showed more infiltration of inflammatory cells. We conclude that sTNFRI, A-85783, and L-NAME can be proposed as alternative future treatments for otitis media with effusion. However, L-NAME may be the least effective of these agents.

  13. Sub-chronic lead exposure produces β1-adrenoceptor downregulation decreasing arterial pressure reactivity in rats.

    Toscano, Cindy Medici; Simões, Maylla Ronacher; Alonso, Maria Jesus; Salaices, Mercedes; Vassallo, Dalton Valentim; Fioresi, Mirian

    2017-07-01

    Lead is considered a causative factor for hypertension and other cardiovascular diseases. To investigate the effects of sub-chronic lead exposure on blood pressure reactivity and cardiac β 1 -adrenoceptor activity and to evaluate whether the effects found in vitro are similar to those found in vivo. Male Wistar rats were randomly distributed into two groups: control rats (Ct) and rats administered drinking water containing 100ppm lead (Pb) for 30days. Blood pressure in the Pb rats increased starting from the first week of treatment until the end of the study [systolic blood pressure, Ct: 122±4 vs. Pb: 143±3mmHg; diastolic blood pressure, Ct: 63±4 vs. Pb: 84±4mmHg]. The heart rate was also increased (Ct: 299±11 vs. Pb: 365±11bpm), but the pressure reactivity to phenylephrine was decreased. Losartan and hexamethonium exhibited a greater reduction in blood pressure of Pb rats than in the Ct rats. Isoproterenol increased the left ventricular systolic and end-diastolic pressure, and heart rate only in Ct rats, suggesting that lead induced β 1 -adrenoceptor downregulation. Indomethacin reduced the blood pressure and heart rate in the Pb rats, suggesting the involvement of cyclooxygenase-derived products (which are associated with reduced nitric oxide bioavailability) in this process. These findings offer further evidence that the effects of sub-chronic lead exposure in vitro can be reproduced in vivo-even at low concentrations-thus triggering mechanisms for the development of hypertension. Therefore, lead should be considered an environmental risk factor for cardiovascular disease. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Dexmedetomidine improves neurologic outcome from incomplete ischemia in the rat. Reversal by the alpha 2-adrenergic antagonist atipamezole.

    Hoffman, W E; Kochs, E; Werner, C; Thomas, C; Albrecht, R F

    1991-08-01

    Dexmedetomidine is an alpha 2-adrenergic agonist that decreases central sympathetic activity and reduces the anesthetic requirement for halothane. We evaluated the effect of dexmedetomidine on neurologic and histopathologic outcome from incomplete cerebral ischemia in the rat. Anesthesia was maintained with a 25-micrograms.kg-1.h-1 fentanyl infusion combined with 70% nitrous oxide. Incomplete ischemia was produced by unilateral carotid artery ligation combined with hemorrhagic hypotension to 35 mmHg for 30 min. Arterial blood gas tensions, pH, and head temperature were maintained at normal levels during the experiment. Four ischemic groups were tested: group 1 (n = 15) received an intraperitoneal (ip) saline injection (control); group 2 (n = 10) received an ip injection of 10 micrograms/kg dexmedetomidine 30 min before ischemia; group 3 (n = 10) received 100 micrograms/kg dexmedetomidine; and group 4 (n = 10) received 100 micrograms/kg dexmedetomidine plus 1 mg/kg atipamezole (an alpha 2-adrenergic antagonist). Neurologic outcome was evaluated for 3 days using a graded deficit score. Histopathology was evaluated in coronal section in caudate and hippocampal tissue segments. Dexmedetomidine (10 and 100 micrograms/kg) significantly decreased plasma catecholamines and improved neurologic and histopathologic outcome in a dose-dependent manner compared to control rats (P less than 0.05). Atipamezole abolished the decrease in catecholamines and the improvement in outcome seen with dexmedetomidine, confirming that these effects were mediated by alpha 2-adrenergic receptors. It is concluded that alpha 2-adrenoreceptor stimulation decreases sympathetic activity and decreases ischemic injury in a model of incomplete cerebral ischemia.

  15. Identification of an endogenous alpha-adrenergic receptor antagonist: studies on its possible role in endocrine and cardiovascular function

    Dunbar, J.C.; Wider, M.; House, F.; Campbell, R.

    1986-01-01

    The concept of α and β adrenergic receptors that are regulated by epinephrine or norepinephrine (NE) is well established. The reported receptor antagonists have been synthetic. A peptide extracted from the duodenal mucosa with α-2 antagonist properties has been identified. It specifically inhibits 3 H-yohimbine binding (α-2) but not 3 H dihydroalprenolol (β) binding in whole brain membranes. Partially purified preparations of the alpha receptor binding inhibitor (ABI) were tested for endocrine pancreatic and cardiovascular effects. When isolated islets were incubated in the presence of ABI with and without NE, ABI along did not alter insulin secretion but completely reversed the NE suppression of glucose stimulated insulin release. Glucagon secretion by these same islets was enhanced by ABI and augmented the stimulatory effect of NE. Intravenous (I.V.) infusion of ABI increased serum insulin in the presence of NE and decreased the serum glucose response to a glucose load. Infusion of ABI into the 4th ventricle, or I.V. resulted in a decrease (50-60%) in systolic and diastolic blood pressure as well as a decrease (10-20%) in heart rate. From these studies the authors conclude that a duodenal peptide with the capacity to inhibit α-2 agonist binding may play a role in endocrine and cardiovascular functions

  16. Discovery of an imidazopyridine-containing 1,4-benzodiazepine nonpeptide vitronectin receptor (alpha v beta 3) antagonist with efficacy in a restenosis model.

    Keenan, R M; Lago, M A; Miller, W H; Ali, F E; Cousins, R D; Hall, L B; Hwang, S M; Jakas, D R; Kwon, C; Louden, C; Nguyen, T T; Ohlstein, E H; Rieman, D J; Ross, S T; Samanen, J M; Smith, B R; Stadel, J; Takata, D T; Vickery, L; Yuan, C C; Yue, T L

    1998-11-17

    In the 3-oxo-1,4-benzodiazepine-2-acetic acid series of vitronectin receptor (alpha v beta 3) antagonists, a compound containing an imidazopyridine arginine mimetic was discovered which had sufficient potency and i.v. pharmacokinetics for demonstration of efficacy in a rat restenosis model.

  17. Reactivation of pulmonary tuberculosis (TBC) with the use of antagonist of the tumor necrosis factor alpha (FNTα) in rheumatoid arthritis: On purpose of a case

    Martinez V, Jose B; Medina V, Yimy F; Parga, Roberto; Restrepo, Jose Felix; Iglesias G, Antonio; Rondon, Federico

    2005-01-01

    Woman 56 years old, with history of rheumatoid arthritis who develops reactivation of pulmonary tuberculosis (TBC) after 1 year of treatment with biological therapy (antagonist of the tumor necrosis factor alpha). It is discussed pathophysiologic mechanisms, diagnostic approach, treatment of TBC and some recommendations for the use of biological therapy in patients with rheumatic disease

  18. Effects of chronic isoproterenol administration of β1-adrenoceptors and growth of pancreas of young and adult rats

    Schneyer, C.A.; Humphreys-Beher, M.

    1988-01-01

    [ 3 H]Dihydroalprenolol (DHA) binding of membranes of adult pancreas differed from that of pancreas of young rats, and the DHA binding in the presence of atenolol or butoxamine also was different in the two age groups. The adult pancreas had 93% β 2 - and 7% β 1 -adrenoceptors and did not exhibit an increased incorporation of [ 3 H]thymidine into deoxyribonucleic acid (DNA) following 2 days of DL-isoproterenol (ISO) administration; in contrast, pancreas of the 20-day-old rat had 71% β 2 -adrenoceptors and 27% β 1 -adrenoceptors and exhibited a 34-fold increase over that of adult, and a 6-fold increase over that of the control 20-day-old pancreas. Acinar cell differentiation was also accelerated by a 7-day regimen of ISO administration from 13 to 20 days of age. These growth responses to ISO appear to be β 1 mediated. The lack of β 1 -adrenoceptors in the adult may account for the failure of the adult pancreas to exhibit a growth response to ISO

  19. The anticancer estrogen receptor antagonist tamoxifen impairs consolidation of inhibitory avoidance memory through estrogen receptor alpha.

    Lichtenfels, Martina; Dornelles, Arethuza da Silva; Petry, Fernanda Dos Santos; Blank, Martina; de Farias, Caroline Brunetto; Roesler, Rafael; Schwartsmann, Gilberto

    2017-11-01

    Over two-thirds of women with breast cancer have positive tumors for hormone receptors, and these patients undergo treatment with endocrine therapy, tamoxifen being the most widely used agent. Despite being very effective in breast cancer treatment, tamoxifen is associated with side effects that include cognitive impairments. However, the specific aspects and mechanisms underlying these impairments remain to be characterized. Here, we have investigated the effects of tamoxifen and interaction with estrogen receptors on formation of memory for inhibitory avoidance conditioning in female rats. In the first experiment, Wistar female rats received a single oral dose of tamoxifen (1, 3, or 10 mg/kg) or saline by gavage immediately after training and were tested for memory consolidation 24 h after training. In the second experiment, rats received a single dose of 1 mg/kg tamoxifen or saline by gavage 3 h after training and were tested 24 h after training for memory consolidation. In the third experiment, rats received a subcutaneous injection with estrogen receptor α agonist or estrogen receptor beta agonist 30 min before the training. After training, rats received a single oral dose of tamoxifen 1 mg/kg or saline and were tested 24 h after training. In the fourth experiment, rats were trained and tested 24 h later. Immediately after test, rats received a single dose of tamoxifen (1 mg/kg) or saline by gavage and were given four additional daily test trials followed by a re-instatement. Tamoxifen at 1 mg/kg impaired memory consolidation when given immediately after training and the estrogen receptor alpha agonist improved the tamoxifen-related memory impairment. Moreover, tamoxifen impairs memory consolidation of the test. These findings indicate that estrogen receptors regulate the early phase of memory consolidation and the effects of tamoxifen on memory consolidation.

  20. β1-Adrenoceptor autoantibodies affect action potential duration and delayed rectifier potassium currents in guinea pigs.

    Zhao, Yuhui; Huang, Haixia; Du, Yunhui; Li, Xiao; Lv, Tingting; Zhang, Suli; Wei, Hua; Shang, Jianyu; Liu, Ping; Liu, Huirong

    2015-01-01

    β1-Adrenoceptor autoantibodies (β1-AAs) affect the action potential duration (APD) in cardiomyocytes and are related to ventricular arrhythmias. The delayed rectifier potassium current (I K) plays a crucial role in APD, but the effects of β1-AAs on I K have not been completely illuminated. This work aimed to observe the effects of β1-AAs on I K and APD and further explore the mechanisms of β1-AA-mediated ventricular arrhythmias. β1-AAs were obtained from sera of patients with coronary heart disease (CHD) and nonsustained ventricular tachycardia. With whole-cell patch clamp technique, action potentials and I K were recorded. The results illustrated 0.1 μmol/L β1-AAs shortened APD at 50 % (APD50) and 90 % (APD90) of the repolarization. However, at 0.01 μmol/L, β1-AAs had no effects on either APD90 or APD50 (P > 0.05). At 0.001 μmol/L, β1-AAs significantly prolonged APD90 and APD50. Moreover, β1-AAs (0.001, 0.01, 0.1 μmol/L) dose-dependently increased the rapidly activating delayed rectifier potassium current (I Kr), but similarly decreased the slowly activating delayed rectifier potassium current (I Ks) and increased L-type calcium currents at the different concentrations. Taken together, the IKr increase induced by high β1-AA concentrations is responsible for a significant APD reduction which would contribute to repolarization changes and trigger the malignant ventricular arrhythmias in CHD patients.

  1. Antagonist effect of triptolide on AKT activation by truncated retinoid X receptor-alpha.

    Na Lu

    Full Text Available BACKGROUND: Retinoid X receptor-alpha (RXRα is a key member of the nuclear receptor superfamily. We recently demonstrated that proteolytic cleavage of RXRα resulted in production of a truncated product, tRXRα, which promotes cancer cell survival by activating phosphatidylinositol-3-OH kinase (PI3K/AKT pathway. However, how the tRXRα-mediated signaling pathway in cancer cells is regulated remains elusive. METHODOLOGY/PRINCIPAL FINDINGS: We screened a natural product library for tRXRα targeting leads and identified that triptolide, an active component isolated from traditional Chinese herb Trypterygium wilfordii Hook F, could modulate tRXRα-mediated cancer cell survival pathway in vitro and in animals. Our results reveal that triptolide strongly induces cancer cell apoptosis dependent on intracellular tRXRα expression levels, demonstrating that tRXRα serves as an important intracellular target of triptolide. We show that triptolide selectively induces tRXRα degradation and inhibits tRXRα-dependent AKT activity without affecting the full-length RXRα. Interestingly, such effects of triptolide are due to its activation of p38. Although triptolide also activates Erk1/2 and MAPK pathways, the effects of triptolide on tRXRα degradation and AKT activity are only reversed by p38 siRNA and p38 inhibitor. In addition, the p38 inhibitor potently inhibits tRXRα interaction with p85α leading to AKT inactivation. Our results demonstrate an interesting novel signaling interplay between p38 and AKT through tRXRα mediation. We finally show that targeting tRXRα by triptolide strongly activates TNFα death signaling and enhances the anticancer activity of other chemotherapies. CONCLUSIONS/SIGNIFICANCE: Our results identify triptolide as a new xenobiotic regulator of the tRXRα-dependent survival pathway and provide new insight into the mechanism by which triptolide acts to induce apoptosis of cancer cells. Triptolide represents one of the most

  2. The effects of the alpha2-adrenergic receptor agonists clonidine and rilmenidine, and antagonists yohimbine and efaroxan, on the spinal cholinergic receptor system in the rat

    Abelson, Klas S P; Höglund, A Urban

    2004-01-01

    Cholinergic agonists produce spinal antinociception via mechanisms involving an increased release of intraspinal acetylcholine. The cholinergic receptor system interacts with several other receptor types, such as alpha2-adrenergic receptors. To fully understand these interactions, the effects...... of various receptor ligands on the cholinergic system must be investigated in detail. This study was initiated to investigate the effects of the alpha2-adrenergic receptor agonists clonidine and rilmenidine and the alpha2-adrenergic receptor antagonists yohimbine and efaroxan on spinal cholinergic receptors......, all ligands possessed affinity for nicotinic receptors. Clonidine and yohimbine binding was best fit to a one site binding curve and rilmenidine and efaroxan to a two site binding curve. The present study demonstrates that the tested alpha2-adrenergic receptor ligands affect intraspinal acetylcholine...

  3. [Distribution and significance of α1-adrenoceptor subtypes in patients with chronic prostatitis in prostate, bladder detrusor and posterior urethral tissue].

    Yang, Yu; Xie, Hui; Zheng, Jian-jian; Chen, Bi-cheng; He, Qiu-xiang; Shen, Ji-hong

    2010-12-14

    To study the distribution of alpha1-adrenoceptor (α1-AR) subtype in prostate, posterior urethra and bladder detrusor of patients with chronic prostatitis (CP). The prostate specimens were collected at autopsy from 30 organ donors (aged 20-35 years old) dying of non-prostatic diseases. The pathological specimens of prostate peripheral zone were examined. The method of real-time reverse transcriptase polymerase chain reaction (real-time RT-PCR) was employed for quantification of α1a-AR and α1b-AR subtype expression in prostate transition zone and its surrounding zone, posterior urethra and bladder detrusor tissue. Among all donors, there were 24 cases with pathological inflammation in prostatic peripheral zone and 6 with pathological non-inflammation. The mRNA expression of α1-AR subtypes in bladder detrusor and posterior urethra was significantly higher in the inflammation group than in the control group (Pposterior urethra was significantly lower in the inflammation group than in the control group (Pposterior urethra may explain various urodynamic changes in CP and lead to the occurrence and development of CP in prostate, posterior urethra and bladder detrusor.

  4. Comparison of vascular alpha(1)-adrenoceptor antagonism of tamsulosin in oral controlled absorption system (OCAS) and modified release (MR) formulations

    Michel, M. C.; Korstanje, C.; Krauwinkel, W.; Shear, M.; Davies, J.; Quartel, A.

    2005-01-01

    Objective: The cardiovascular a-l-adrenoceptor (AR) antagonism of the new oral controlled absorption system (OCAS) 0.4 mg tablet formulation of tamsulosin was compared with that of the modified release (MR) 0.4 mg capsule formulation in healthy male volunteers after a single dose in the fasted

  5. Neomycin is a platelet-derived growth factor (PDGF) antagonist that allows discrimination of PDGF alpha- and beta-receptor signals in cells expressing both receptor types.

    Vassbotn, F S; Ostman, A; Siegbahn, A; Holmsen, H; Heldin, C H

    1992-08-05

    The aminoglycoside neomycin has recently been found to affect certain platelet-derived growth factor (PDGF) responses in C3H/10T1/2 C18 fibroblasts. Using porcine aortic endothelial cells transfected with PDGF alpha- or beta-receptors, we explored the possibility that neomycin interferes with the interaction between the different PDGF isoforms and their receptors. We found that neomycin (5 mM) inhibited the binding of 125I-PDGF-BB to the alpha-receptor with only partial effect on the binding of 125I-PDGF-AA; in contrast, the binding of 125I-PDGF-BB to the beta-receptor was not affected by the aminoglycoside. Scatchard analyses showed that neomycin (5 mM) decreased the number of binding sites for PDGF-BB on alpha-receptor-expressing cells by 87%. Together with cross-competition studies with 125I-labeled PDGF homodimers, the effect of neomycin indicates that PDGF-AA and PDGF-BB bind to both common and unique structures on the PDGF alpha-receptor. Neomycin specifically inhibited the autophosphorylation of the alpha-receptor by PDGF-BB, with less effect on the phosphorylation induced by PDGF-AA and no effect on the phosphorylation of the beta-receptor by PDGF-BB. Thus, neomycin is a PDGF isoform- and receptor-specific antagonist that provides a possibility to compare the signal transduction pathways of alpha- and beta-receptors in cells expressing both receptor types. This approach was used to show that activation of PDGF beta-receptors by PDGF-BB mediated a chemotactic response in human fibroblasts, whereas activation of alpha-receptors by the same ligand inhibited chemotaxis.

  6. Mechanisms of IhERG/IKr Modulation by α1-Adrenoceptors in HEK293 Cells and Cardiac Myocytes

    Janire Urrutia

    2016-12-01

    Full Text Available Background: The rapid delayed rectifier K+ current (IKr, carried by the hERG protein, is one of the main repolarising currents in the human heart and a reduction of this current increases the risk of ventricular fibrillation. α1-adrenoceptors (α1-AR activation reduces IKr but, despite the clear relationship between an increase in the sympathetic tone and arrhythmias, the mechanisms underlying the α1-AR regulation of the hERG channel are controversial. Thus, we aimed to investigate the mechanisms by which α1-AR stimulation regulates IKr. Methods: α1-adrenoceptors, hERG channels, auxiliary subunits minK and MIRP1, the non PIP2-interacting mutant D-hERG (with a deletion of the 883-894 amino acids in the C-terminal and the non PKC-phosphorylable mutant N-terminal truncated-hERG (NTK-hERG were transfected in HEK293 cells. Cell membranes were extracted by centrifugation and the different proteins were visualized by Western blot. Potassium currents were recorded by the patch-clamp technique. IKr was recorded in isolated feline cardiac myocytes. Results: Activation of the α1-AR reduces the amplitude of IhERG and IKr through a positive shift in the activation half voltage, which reduces the channel availability at physiological membrane potentials. The intracellular pathway connecting the α1-AR to the hERG channel in HEK293 cells includes activation of the Gαq protein, PLC activation and PIP2 hydrolysis, activation of PKC and direct phosphorylation of the hERG channel N-terminal. The PKC-mediated IKr channel phosphorylation and subsequent IKr reduction after α1-AR stimulation was corroborated in feline cardiac myocytes. Conclusions: These findings clarify the link between sympathetic nervous system hyperactivity and IKr reduction, one of the best characterized causes of torsades de pointes and ventricular fibrillation.

  7. Effect of addition of yohimbine (alpha-2-receptor antagonist) to the antidepressant activity of fluoxetine or venlafaxine in the mouse forced swim test.

    Dhir, Ashish; Kulkarni, S K

    2007-01-01

    Studies have suggested that alpha(2)-adrenoceptors strongly affect monoaminergic neurotransmission by enhancing not only noradrenergic but also serotonergic firing rates. With this background in mind, the present study was undertaken to monitor the effect of addition of yohimbine (alpha(2)-adrenoceptor antagonist) to the effect of fluoxetine (selective serotonin reuptake inhibitor) or venlafaxine (dual reuptake inhibitors of both serotonin and norepinephrine) in Porsolt's forced swim test (FST) using male Laca strain mice. The immobility period was recorded in mouse FST during a 6-min period. Different doses of fluoxetine or venlafaxine were administered 30 min before exposing the animals to the test procedure. In the combination study, yohimbine (2 mg/kg i.p.) was administered 15 min before the administration of different doses of fluoxetine or venlafaxine. Fluoxetine (5, 10, 20 and 40 mg/kg) [F = 28.352] or venlafaxine (2, 4, 8 and 16 mg/kg) [F = 17.842] dose-dependently inhibited the immobility period in mice. Addition of yohimbine (2 mg/kg i.p.) potentiated the antidepressant action of fluoxetine or venlafaxine in mouse FST as the animals showed a decrease in the immobility period compared to the fluoxetine or venlafaxine per se group, respectively. The present study not only demonstrated the association of alpha(2)-receptors in the antidepressant effect of fluoxetine or venlafaxine, but also supports its adjuvant therapy with other antidepressant drugs. (c) 2007 S. Karger AG, Basel.

  8. Design and synthesis of novel sulfonamide-containing bradykinin hB2 receptor antagonists. 2. Synthesis and structure-activity relationships of alpha,alpha-cycloalkylglycine sulfonamides.

    Fattori, Daniela; Rossi, Cristina; Fincham, Christopher I; Caciagli, Valerio; Catrambone, Fernando; D'Andrea, Piero; Felicetti, Patrizia; Gensini, Martina; Marastoni, Elena; Nannicini, Rossano; Paris, Marielle; Terracciano, Rosa; Bressan, Alessandro; Giuliani, Sandro; Maggi, Carlo A; Meini, Stefania; Valenti, Claudio; Quartara, Laura

    2007-02-08

    Recently we reported on the design and synthesis of a novel class of selective nonpeptide bradykinin (BK) B2 receptor antagonists (J. Med. Chem. 2006, 3602-3613). This work led to the discovery of MEN 15442, an antagonist with subnanomolar affinity for the human B2 receptor (hB2R), which also displayed significant and prolonged activity in vivo (for up to 210 min) against BK-induced bronchoconstriction in the guinea-pig at a dose of 300 nmol/kg (it), while demonstrating only a slight effect on BK-induced hypotension. Here we describe the further optimization of this series of compounds aimed at maximizing the effect on bronchoconstriction and minimizing the effect on hypotension, with a view to developing topically delivered drugs for airway diseases. The work led to the discovery of MEN 16132, a compound which, after intratracheal or aerosol administration, inhibited, in a dose-dependent manner, BK-induced bronchoconstricton in the airways, while showing minimal systemic activity. This compound was selected as a preclinical candidate for the topical treatment of airway diseases involving kinin B2 receptor stimulation.

  9. Novel 4-phenylpiperidine-2,6-dione derivatives. Ligands for α1-adrenoceptor subtypes

    Romeo, Giuseppe F.

    2011-07-01

    A number of new 4-phenylpiperidine-2,6-diones bearing at the 1-position an ω-[4-(substituted phenyl)piperazin-1-yl]alkyl moiety were designed and synthesized as ligands for the α1-adrenergic receptor (α1-AR) subtypes. Some synthesized compounds, tested in binding assays for the human cloned α1A-, α1B-, and α1D-AR subtypes, displayed affinities in the nanomolar range. Highest affinity values were found in derivatives having a butyl connecting chain between the 4-phenylpiperidine-2,6-dione and the phenylpiperazinyl moieties. 1-[4-[4-(2-Methoxyphenyl)piperazin-1-yl]butyl]-4-phenylpiperidine-2,6- dione (34) showed the best affinity for the α1A-AR (pK i = 8.74) and 10-fold selectivity compared to the other two α1-AR subtypes. Some representative compounds were also tested in order to evaluate their effects on the signal transduction pathway coupled to α1-AR subtypes. They all blocked norepinephrine-induced stimulation of inositol phospholipid hydrolysis, thus behaving as antagonists. Binding data were used to refine a previously developed pharmacophoric model for α1D-ARs. The revised model shows a highly predictive power and could be useful for the future design of high affinity α1D-AR ligands. © 2011 Elsevier Masson SAS. All rights reserved.

  10. Role of beta1-adrenoceptor in the basolateral amygdala of rats with anxiety-like behavior.

    Fu, Ailing; Li, Xiaorong; Zhao, Baoquan

    2008-05-23

    There are evidence suggesting that the function of adrenergic receptor is affected in the amygdala of animals with anxiety-like behavior. However, beta-adrenoceptor (beta-AR) subtypes, consisting of three subtypes, exert different effects on anxiety regulation. In order to determine the function of the beta1-AR subtype in anxiety-like behavior, we investigated the change of beta1-AR expression by immunostaining in the basolateral amygdala (BLA) of rats treated by conditional fear training. The results indicated that the level of beta1-AR was significantly increased in the BLA of fear-conditioned animals as compared that of controls. In animal behavioral tests, animals treated with selective beta1-AR antagonist metoprolol before conditional fear training exhibited a significant attenuation of anxiety-like behavior characterized by increased percentage of time spent and percentage of entries in the open arms, and increased number of head-dips in the elevated plus-maze (EPM) test compared with the animals treated with only saline. Furthermore, the rats pretreated with metoprolol in the conditional fear training significantly decreased the freezing behavior in the test compared with the controls. The results suggested that the beta1-AR played an important role in anxiety-like behavior, and inhibition of the beta1-AR in the BLA could produce anxiolytic effect.

  11. Novel 4-phenylpiperidine-2,6-dione derivatives. Ligands for α1-adrenoceptor subtypes

    Romeo, Giuseppe F.; Materia, Luisa; Modica, Maria Nunziata; Pittal, Valeria; Salerno, Loredana; Siracusa, Maria Angela; Manetti, Fabrizio; Botta, Maurizio; Minneman, Kenneth P.

    2011-01-01

    A number of new 4-phenylpiperidine-2,6-diones bearing at the 1-position an ω-[4-(substituted phenyl)piperazin-1-yl]alkyl moiety were designed and synthesized as ligands for the α1-adrenergic receptor (α1-AR) subtypes. Some synthesized compounds, tested in binding assays for the human cloned α1A-, α1B-, and α1D-AR subtypes, displayed affinities in the nanomolar range. Highest affinity values were found in derivatives having a butyl connecting chain between the 4-phenylpiperidine-2,6-dione and the phenylpiperazinyl moieties. 1-[4-[4-(2-Methoxyphenyl)piperazin-1-yl]butyl]-4-phenylpiperidine-2,6- dione (34) showed the best affinity for the α1A-AR (pK i = 8.74) and 10-fold selectivity compared to the other two α1-AR subtypes. Some representative compounds were also tested in order to evaluate their effects on the signal transduction pathway coupled to α1-AR subtypes. They all blocked norepinephrine-induced stimulation of inositol phospholipid hydrolysis, thus behaving as antagonists. Binding data were used to refine a previously developed pharmacophoric model for α1D-ARs. The revised model shows a highly predictive power and could be useful for the future design of high affinity α1D-AR ligands. © 2011 Elsevier Masson SAS. All rights reserved.

  12. Nutrition, anthropometry, gastrointestinal dysfunction, and circulating levels of tumour necrosis factor alpha receptor I and interleukin-1 receptor antagonist in children during stem cell transplantation

    Andreassen, B. U.; Pærregaard, Anders; Michaelsen, Kim F.

    2008-01-01

    To evaluate anthropometry, nutrition and gastrointestinal dysfunction, and to characterize the relation between these parameters and the inflammatory activity evaluated by plasma levels of soluble tumour necrosis factor alpha receptor I (sTNFRI) and interleukin-1 receptor antagonist (IL-1Ra) levels...... during stem cell transplantation (SCT) in children. Clinical assessments and blood sampling were performed on days -3, 0, +7, +15 and +31 in eight children undergoing SCT. Energy intake, anthropometry, gastrointestinal dysfunction (WHO toxicity score) and sTNFRI and IL-1Ra were evaluated. The energy...... intake was below recommended levels. There was a loss of lean body mass (arm muscle area)(median, 2031 mm(2) (day -3) vs 1477 mm(2) (day 31); p = 0.04), and of fat mass (arm fat area) (791 mm(2) (day -3) vs 648 mm(2) (day +31); p = 0.04). sTNFRI was elevated throughout the course of transplantation...

  13. Evidence that two stereochemically different alpha-2 adrenoceptors modulate norepinephrine release in rat cerebral cortex

    Harsing, L.G. Jr.; Vizi, E.S. (Institute of Experimental Medicine, Budapest (Hungary))

    1991-01-01

    Cerebral cortex slices from the rat were loaded with (3H)norepinephrine ((3H)NE) and superfused in order to measure the release of radioactivity at rest and in response to electrical stimulation. The (-)-isomer and the (+)-isomer of CH-38083 (7,8-(methylenedioxy)-14- alpha-hydroxyalloberbane HCl), a selective alpha-2-adrenoceptor antagonist with an alloberbane skeleton, increased the electrically induced release of (3H)NE in a concentration-dependent manner, and a similar effect was observed with racemic CH-38083 and idazoxan. The stereoisomers of CH-38083 applied in a concentration range of 10(-8) to 10(-6) mol/l were equipotent in facilitating stimulation-evoked (3H)NE release: concentrations needed to enhance tritium outflow by 50% were 1.3 X 10(-7) mol/l for (-)-CH-38083 and 1.4 X 10(-7) mol/l for (+)-CH-38083. Exogenous NE decreased the electrically stimulated release of (3H)NE, and the stereoisomers of CH-38083 antagonized this inhibition with different potencies: the dissociation constant (KB) values for (-)-isomer and for (+)-isomer of CH-38083 were 14.29 and 97.18 nmol/l. These data indicate that presynaptic alpha-2 adrenoceptors that are available for NE released from axon terminals do not show stereospecificity toward enantiomers of CH-38083, whereas those that are occupied by exogenous NE are much more sensitive toward (-)-CH-38083. The alpha-1 adrenoceptor antagonist prazosin also differentiated between the alpha-2 adrenoceptor subtypes: prazosin (10(-6) mol/l) did not alter the increase of electrically induced (3H)NE release evoked by (-)- and (+)-CH-38083; however, in its presence, the stereoisomers of CH-38083 failed to antagonize the inhibitory effect of exogenous NE on its own release.

  14. Apoptosis and the FLIP and NF-kappa B proteins as pharmacodynamic criteria for biosimilar TNF-alpha antagonists

    Urbano PCM

    2014-07-01

    Full Text Available Paulo César Martins Urbano,1 Vanete Thomaz Soccol,1 Valderilio Feijó Azevedo2 1Biotechnology and Bioprocess Engineering Program, Federal University of Parana, Curitiba, Parana, Brazil; 2Hospital de Clínicas, Federal University of Parana, Curitiba, Parana, Brazil Abstract: Various criteria are necessary to assess the efficacy and safety of biological medications in order to grant companies the right to register these medications with the appropriate bodies that regulate their sale. The imminent expiration of the patents on reference biological products which block the cytokine TNF-α (tumor necrosis factor-α raises the possibility of bringing so-called biosimilars to the market (similar to the biologicals of reference products. This occurrence is inevitable, but criteria to adequately evaluate these medications are now needed. Even among controversy, there is a demand from publications correlating the pro-apoptotic mechanism of the original TNF-α antagonists (etanercept, infliximab, adalimumab, golimumab, and certolizumab pegol in the treatment of rheumatoid arthritis and other diseases. In this article, the authors discuss the possibility of utilizing the pro-apoptotic effect correlated with the regulation of the anti-apoptotic proteins FLIP and NF-κB as new criteria for analyzing the pharmacodynamics of possible biosimilar TNF-α antagonists which should be submitted to regulatory agencies for evaluation. Keywords: anti-TNF drugs, rheumatoid arthritis, apoptosis, NF-κB, FLIP

  15. Discovery, SAR, and Radiolabeling of Halogenated Benzimidazole Carboxamide Antagonists as Useful Tools for (alpha)4(beta)1 Integrin Expressed on T- and B-cell Lymphomas

    Carpenter, R D; Natarajan, A; Lau, E Y; Andrei, M; Solano, D M; Lightstone, F C; DeNardo, S J; Lam, K S; Kurth, M J

    2010-02-08

    The cell surface receptor {alpha}{sub 4}{beta}{sub 1} integrin is an attractive yet poorly understood target for selective diagnosis and treatment of T- and B-cell lymphomas. This report focuses on the rapid microwave preparation of medicinally pertinent benzimidazole heterocycles, structure-activity relationships (SAR) of novel halobenzimidazole carboxamide antagonists 3-6, and preliminary biological evaluation of radioiodinated agents 7, 8, and 18. The I-125 derivative 18 had good tumor uptake (12 {+-} 1% ID/g at 24 h; 4.5 {+-} 1% ID/g at 48 h) and tumor:kidney ratio ({approx}4:1 at 24 h; 2.5:1 at 48 h) in xenograft murine models of B-cell lymphoma. Molecular homology models of {alpha}{sub 4}{beta}{sub 1} integrin have predicted that docked halobenzimidazole carboxamides have the halogen atom in a suitable orientation for halogen-hydrogen bonding. These high affinity ({approx} pM binding) halogenated ligands are attractive tools for medicinal and biological use; the fluoro and iodo derivatives are potential radiodiagnostic ({sup 18}F) or radiotherapeutic ({sup 131}I) agents, whereas the chloro and bromo analogues could provide structural insight into integrin-ligand interactions through photoaffinity cross-linking/mass spectroscopy experiments, as well as co-crystallization X-ray studies.

  16. Tc-labeling of Peptidomimetic Antagonist to Selectively Target alpha(v)beta(3) Receptor-Positive Tumor: Comparison of PDA and EDDA as co-Ligands.

    Shin, In Soo; Maeng, Jin Soo; Jang, Beom-Su; You, Eric; Cheng, Kenneth; Li, King C P; Wood, Bradford; Carrasquillo, Jorge A; Danthi, S Narasimhan; Paik, Chang H

    2010-01-01

    OBJECTIVES: The aim of this research was to synthesize radiolabeled peptidomimetic integrin alpha(v)beta(3) antagonist with (99m)Tc for rapid targeting of integrin alpha(v)beta(3) receptors in tumor to produce a high tumor to background ratio. METHODS: The amino terminus of 4-[2-(3,4,5,6-tetra-hydropyrimidin-2-ylamino)-ethyloxy]benzoyl-2-(S)-[N-(3-amino-neopenta-1-carbamyl)]-aminoethylsulfonyl-amino-beta-alanine hydrochloride (IAC) was conjugated with N-hydroxysuccinimide ester of HYNIC and labeled with (99m)Tc using tricine with either 1,5-pyridinedicarboxylic acid (PDA) or ethylenediamine-N,N'-diacetic acid (EDDA) as the co-ligand. The products, (99m)Tc EDDA(2)/HYNIC-IAC (P1) and (99m)Tc PDA (tricin)/HYNIC-IAC (P2) were subjected to in vitro serum stability, receptor-binding, biodistribution and imaging studies. RESULTS: P1 and P2 were synthesized with an overall yield of >80%. P1 was slightly more stable than P2 when incubated in serum at 37 degrees C for 18 hrs (84 vs 77% intact). The In vitro receptor-binding of P1 was higher than that of P2 (78.02 +/- 13.48 vs 51.05 +/- 14.05%) when incubated with alpha(v)beta(3) at a molar excess (0.8 muM). This receptor binding was completely blocked by a molar excess of an unlabeled peptidomimetic antagonist. Their differences shown in serum stability and the receptor-binding appeared to be related to their biological behaviors in tumor uptake and retention; the 1 h tumor uptakes of P1 and P2 were 3.17+/-0.52 and 2.13+/-0.17 % ID/g, respectively. P1 was retained in the tumor longer than P2. P1 was excreted primarily through the renal system whereas P2 complex was excreted equally via both renal and hepatobiliary systems. Thus, P1 was retained in the whole-body with 27.25 +/- 3.67% ID at 4 h whereas 54.04 +/- 3.57% ID of P2 remained in the whole-body at 4 h. This higher whole-body retention of P2 appeared to be resulted from a higher amount of radioactivity retained in liver and intestine. These findings were supported by

  17. Chronic activation of the low affinity site of β1-adrenoceptors stimulates haemodynamics but exacerbates pressure-overload cardiac remodelling

    Kiriazis, Helen; Tugiono, Niquita; Xu, Qi; Gao, Xiao-Ming; Jennings, Nicole L; Ming, Ziqui; Su, Yidan; Klenowski, Paul; Summers, Roger J; Kaumann, Alberto; Molenaar, Peter; Du, Xiao-Jun

    2013-01-01

    BACKGROUND AND PURPOSE The β1-adrenoceptor has at least two binding sites, high and low affinity sites (β1H and β1L, respectively), which mediate cardiostimulation. While β1H-adrenoceptor can be blocked by all clinically used β-blockers, β1L-adrenoceptor is relatively resistant to blockade. Thus, chronic β1L-adrenoceptor activation may mediate persistent cardiostimulation, despite the concurrent blockade of β1H-adrenoceptors. Hence, it is important to determine the potential significance of β1L-adrenoceptors in vivo, particularly in pathological situations. EXPERIMENTAL APPROACH C57Bl/6 male mice were used. Chronic (4 or 8 weeks) β1L-adrenoceptor activation was achieved by treatment, via osmotic mini pumps, with (-)-CGP12177 (10 mg·kg−1·day−1). Cardiac function was assessed by echocardiography and micromanometry. KEY RESULTS (-)-CGP12177 treatment of healthy mice increased heart rate and left ventricular (LV) contractility. (-)-CGP12177 treatment of mice subjected to transverse aorta constriction (TAC), during weeks 4–8 or 4–12 after TAC, led to a positive inotropic effect and exacerbated fibrogenic signalling while cardiac hypertrophy tended to be more severe. (-)-CGP12177 treatment of mice with TAC also exacerbated the myocardial expression of hypertrophic, fibrogenic and inflammatory genes compared to untreated TAC mice. Washout of (-)-CGP12177 revealed a more pronounced cardiac dysfunction after 12 weeks of TAC. CONCLUSIONS AND IMPLICATIONS β1L-adrenoceptor activation provides functional support to the heart, in both normal and pathological (pressure overload) situations. Sustained β1L-adrenoceptor activation in the diseased heart exacerbates LV remodelling and therefore may promote disease progression from compensatory hypertrophy to heart failure. PMID:23750586

  18. The effects of increasing doses of MK-467, a peripheral alpha(2)-adrenergic receptor antagonist, on the cardiopulmonary effects of intravenous dexmedetomidine in conscious dogs.

    Honkavaara, J M; Restitutti, F; Raekallio, M R; Kuusela, E K; Vainio, O M

    2011-08-01

    Different doses of MK-467, a peripheral alpha(2)-adrenergic receptor antagonist, with or without dexmedetomidine were compared in conscious dogs. Eight animals received either dexmedetomidine (10 μg/kg [D]), MK-467 (250 μg/kg [M250] or dexmedetomidine (10 μg/kg) with increasing doses of MK-467 (250 μg/kg [DM250], 500 μg/kg [DM500] and 750 μg/kg [DM750], respectively). Treatments were given intravenously (i.v.) in a randomized, crossover design with a 14-day washout period. Systemic hemodynamics and arterial blood gas analyses were recorded at baseline and at intervals up to 90 min after drugs administration. Dexmedetomidine alone decreased heart rate, cardiac index and tissue oxygen delivery and increased mean arterial pressure and systemic vascular resistance 5 min after administration. DM250 did not completely prevent these early effects, while DM750 induced a decrease in mean arterial pressure. With DM500, systemic hemodynamics remained stable throughout the observational period. MK-467 alone increased cardiac index and tissue oxygen delivery and had no deleterious adverse effects. No differences in arterial blood gases were observed between treatments that included dexmedetomidine. It was concluded that MK-467 attenuated or prevented dexmedetomidine's systemic hemodynamic effects in a dose-dependent manner when given simultaneously i.v. but had no effect on the pulmonary outcome in conscious dogs. A 50:1 dose ratio (MK-467:dexmedetomidine) induced the least alterations in cardiovascular function. © 2010 Blackwell Publishing Ltd.

  19. Basal activity of voltage-gated Ca(2+) channels controls the IP3-mediated contraction by α(1)-adrenoceptor stimulation of mouse aorta segments.

    Leloup, Arthur J; Van Hove, Cor E; De Meyer, Guido R Y; Schrijvers, Dorien M; Fransen, Paul

    2015-08-05

    α1-Adrenoceptor stimulation of mouse aorta causes intracellular Ca(2+) release from sarcoplasmic reticulum Ca(2+) stores via stimulation of inositoltriphosphate (IP3) receptors. It is hypothesized that this Ca(2+) release from the contractile and IP3-sensitive Ca(2+) store is under the continuous dynamic control of time-independent basal Ca(2+) influx via L-type voltage-gated Ca(2+) channels (LCC) residing in their window voltage range. Mouse aortic segments were α1-adrenoceptor stimulated with phenylephrine in the absence of external Ca(2+) (0Ca) to measure phasic isometric contractions. They gradually decreased with time in 0Ca, were inhibited with 2-aminoethoxydiphenyl borate, and declined with previous membrane potential hyperpolarization (levcromakalim) or with previous inhibition of LCC (diltiazem). Former basal stimulation of LCC with depolarization (15 mM K(+)) or with BAY K8644 increased the subsequent phasic contractions by phenylephrine in 0Ca. Although exogenous NO (diethylamine NONOate) reduced the phasic contractions by phenylephrine, stimulation of endothelial cells with acetylcholine in 0Ca failed to attenuate these phasic contractions. Finally, inhibition of the basal release of NO with N(Ω)-nitro-L-arginine methyl ester also attenuated the phasic contractions by phenylephrine. Results indicated that α1-adrenoceptor stimulation with phenylephrine causes phasic contractions, which are controlled by basal LCC and endothelial NO synthase activity. Endothelial NO release by acetylcholine was absent in 0Ca. Given the growing interest in the active regulation of arterial compliance, the dependence of contractile SR Ca(2+) store-refilling in basal conditions on the activity of LCC and basal eNOS may contribute to a more thorough understanding of physiological mechanisms leading to arterial stiffness. Copyright © 2015. Published by Elsevier B.V.

  20. The β3 -adrenoceptor agonist mirabegron increases human atrial force through β1 -adrenoceptors: an indirect mechanism?

    Mo, Weilan; Michel, Martin C; Lee, Xiang Wen; Kaumann, Alberto J; Molenaar, Peter

    2017-08-01

    Mirabegron has been classified as a β 3 -adrenoceptor agonist approved for overactive bladder syndrome. We investigated possible cardiac effects of mirabegron in the absence or presence of β-adrenoceptor subtype antagonists. In view of its phenylethanolamine structure, we investigated whether mirabegron has indirect sympathomimetic activity by using neuronal uptake blockers. Right atrial trabeculae, from non-failing hearts, were paced and contractile force measured at 37°C. Single concentrations of mirabegron were added in the absence or presence of the phosphodiesterase inhibitor 3-isobutyl-1-methylxanthine (IBMX), β 3 (L-748,337), β 1 (CGP 20712A), β 2 (ICI 118,551) -adrenoceptor antagonists, neuronal uptake inhibitors desipramine or phenoxybenzamine. Mirabegron significantly increased contractile force in human right atrium (1 μM, 7.6 ± 2.6%, n = 7; 10 μM, 10.2 ± 1.5%, n = 22 compared with (-)-isoprenaline P < 0.05). In the presence of IBMX, mirabegron (10 μM) caused a greater contraction. L-748,337 (100 nM) had no effect on the increase in contractile force caused by mirabegron (10 μM). In contrast, mirabegron (10 μM) reduced contractile force in the presence of CGP 20712A, which was not affected by L-748,337 (100 nM) or ICI 118,551 (50 nM). Mirabegron (10 μM) also reduced contractile force in the presence of desipramine or phenoxybenzamine. Mirabegron increases human atrial force through β 1 - but not β 3 -adrenoceptors. Desipramine and phenoxybenzamine block neuronal uptake and conceivably prevent mirabegron from releasing noradrenaline. A non-specific cardiodepressant effect is not mediated through β 3 (or β 2 )-adrenoceptors, consistent with lack of β 3 -adrenoceptor function on human atrial contractility. © 2017 The British Pharmacological Society.

  1. Effect of Block of alpha(1)-adrenoceptors on Overall Motor Activity but not on Spatial Cognition in the Object-Position Recognition Task

    Levčík, David; Stuchlík, Aleš; Klement, Daniel

    2013-01-01

    Roč. 62, č. 5 (2013), s. 561-567 ISSN 0862-8408 R&D Projects: GA ČR(CZ) GBP304/12/G069; GA MZd(CZ) NT13386 Grant - others:Rada Programu interní podpory projektů mezinárodní spolupráce AV ČR(CZ) M200111204 Institutional support: RVO:67985823 Keywords : recognition * prazosin * rat * learning Subject RIV: FH - Neurology Impact factor: 1.487, year: 2013

  2. Influence of the low thyroid state in diabetes mellitus on cardiac function and inotropic responsiveness to alpha 1-adrenoceptor stimulation: comparison with the role of hypothyroidism alone

    Beenen, O. H.; Pfaffendorf, M.; van Zwieten, P. A.

    1996-01-01

    The hypothyroid state accompanying diabetes mellitus has been suggested to be partly responsible for the diabetes-induced metabolic, hemodynamic, and pharmacological cardiovascular changes. We assessed the effectivity of streptozotocin (STZ) to induce diabetes mellitus and a hypothyroid state.

  3. β1-Adrenoceptor in the Central Amygdala Is Required for Unconditioned Stimulus-Induced Drug Memory Reconsolidation

    Zhu, Huiwen; Zhou, Yiming; Liu, Zhiyuan; Chen, Xi; Li, Yanqing; Liu, Xing; Ma, Lan

    2018-01-01

    Abstract Background Drug memories become labile and reconsolidated after retrieval by presentation of environmental cues (conditioned stimulus) or drugs (unconditioned stimulus). Whether conditioned stimulus and unconditioned stimulus retrieval trigger different memory reconsolidation processes is not clear. Methods Protein synthesis inhibitor or β-adrenergic receptor (β-AR) antagonist was systemically administrated or intra-central amygdala infused immediately after cocaine reexposure in cocaine-conditioned place preference or self-administration mice models. β-ARs were selectively knocked out in the central amygdala to further confirm the role of β-adrenergic receptor in cocaine reexposure-induced memory reconsolidation of cocaine-conditioned place preference. Results Cocaine reexposure triggered de novo protein synthesis dependent memory reconsolidation of cocaine-conditioned place preference. Cocaine-priming-induced reinstatement was also impaired with post cocaine retrieval manipulation, in contrast to the relapse behavior with post context retrieval manipulation. Cocaine retrieval, but not context retrieval, induced central amygdala activation. Protein synthesis inhibitor or β1-adrenergic receptor antagonist infused in the central amygdala after cocaine retrieval, but not context retrieval, inhibited memory reconsolidation and reinstatement. β1-adrenergic receptor knockout in the central amygdala suppressed cocaine retrieval-triggered memory reconsolidation and reinstatement of cocaine conditioned place preference. β1-adrenergic receptor antagonism after cocaine retrieval also impaired reconsolidation and reinstatement of cocaine self-administration. Conclusions Cocaine reward memory triggered by unconditioned stimulus retrieval is distinct from conditioned stimulus retrieval. Unconditioned stimulus retrieval induced reconsolidation of cocaine reward memory depends on β1-adrenergic signaling in the central amygdala. Post unconditioned stimulus

  4. The MAPKERK-1,2 pathway integrates distinct and antagonistic signals from TGF alpha and FGF7 in morphogenesis of mouse mammary epithelium

    Fata, Jimmie E; Mori, Hidetoshi; Ewald, Andrew J; Zhang, Hui; Yao, Evelyn; Werb, Zena; Bissell, Mina J

    2006-10-03

    Transforming growth factor-{alpha} (TGF{alpha}) and fibroblast growth factor-7 (FGF7) exhibit distinct expression patterns in the mammary gland. Both factors signal through mitogen-activated kinase/extracellular regulated kinase-1,2 (MAPK{sup ERK1,2}); however, their unique and/or combined contributions to mammary morphogenesis have not been examined. In ex vivo mammary explants, we show that a sustained activation of MAPK{sup ERK1,2} for 1 h, induced by TGF{alpha}, was necessary and sufficient to initiate branching morphogenesis, whereas a transient activation (15 min) of MAPK{sup ERK1,2}, induced by FGF7, led to growth without branching. Unlike TGF{alpha}, FGF7 promoted sustained proliferation as well as ectopic localization of, and increase in, keratin-6 expressing cells. The response of the explants to FGF10 was similar to that to FGF7. Simultaneous stimulation by FGF7 and TGF{alpha} indicated that the FGF7-induced MAPK{sup ERK1,2} signaling and associated phenotypes were dominant: FGF7 may prevent branching by suppression of two necessary TGF{alpha}-induced morphogenetic effectors, matrix metalloproteinase-3 (MMP-3/stromelysin-1), and fibronectin. Our findings indicate that expression of morphogenetic effectors, proliferation, and cell-type decisions during mammary organoid morphogenesis are intimately dependent on the duration of activation of MAPK{sup ERK1,2} activation.

  5. 3 alpha 5 beta-Pregnanolone glutamate, a use-dependent NMDA antagonist, reversed spatial learning deficit in an animal model of schizophrenia

    Valeš, Karel; Rambousek, Lukáš; Holubová, Kristína; Svoboda, Jan; Bubeníková-Valešová, V.; Chodounská, Hana; Vyklický ml., Ladislav; Stuchlík, Aleš

    2012-01-01

    Roč. 235, č. 1 (2012), s. 82-88 ISSN 0166-4328 R&D Projects: GA MZd(CZ) NS10365 Institutional research plan: CEZ:AV0Z50110509 Institutional support: RVO:67985823 ; RVO:61388963 Keywords : schizophrenia-like behavior * MK-801 * use-dependent * NMDA antagonist * anxiety * pregnanolone glutamate * Carousel maze Subject RIV: FH - Neurology Impact factor: 3.327, year: 2012

  6. TITERS OF ANTIBODIES TO Β1-ADRENOCEPTOR AND M2 CHOLINERGIC RECEPTORS IN PATIENTS WITH VENTRICULAR ARRHYTHMIAS WITHOUT AN ORGANIC CARDIOVASCULAR DISEASE AND THEIR POSSIBLE CLINICAL SIGNIFICANCE

    M. M. Rogova

    2012-01-01

    Full Text Available Aim. To identify the most promising epitopes that simulate various sites β1-adrenergic and M2-cholinergic receptors, and to evaluate their possible contribution to the development and maintenance of cardiac arrhythmias, particularly idiopathic ventricular arrhythmia. Material and methods. Patients with ventricular arrhythmias without organic cardiovascular disease (the study group; n=70 were included in the study. The control group consisted of 20 healthy volunteers. Evaluation of levels of antibodies to antigenic determinants, modeling various sites β1-adrenergic and M2-cholinergic performed in all patients. Causal treatment with clarithromycin and valacyclovir performed in part of patients. Results. Antibodies to different peptide sequences of β1-adrenergic and M2-cholinergic receptors have been identified in 25% of main group patients. A direct correlation between the frequency of episodes of ventricular tachycardia and IgG levels to MRI-MRIV (p=0.02 revealed. Increase in titre of antibodies to β1-adrenoceptors, to a peptide sequence β8 (p=0.02, and lower titers of antibodies to the M2 acetylcholine receptor — chimera MRI-MRIV IgM (p=0.06 and ARI-MRIV IgM (p=0.07 were observed when assessing the efficacy of the therapy in the causal dynamics in the group of "untreated" patients. IgG titer reduction of ARI-MRIV (p=0.02, which is 4 times out of 10 with reduction of ventricular ectopic activity , recorded after valacyclovir therapy. Clarithromycin therapy on the level of antibodies exerted no significant effect. Conclusion. Possible involvement of antibodies to β1-adrenoceptor and M2-cholinergic receptors in the development of idiopathic ventricular arrhythmias demonstrated. The relationship between the frequency of episodes of ventricular tachycardia and levels of antibody titers to M2-cholinergic receptors found. Attempt of causal treatment, depending on the possible mechanisms of the autoimmune process is executed. Further studies to

  7. Inward rectifier K+ channel and T-type Ca2+ channel contribute to enhancement of GABAergic transmission induced by β1-adrenoceptor in the prefrontal cortex.

    Luo, Fei; Zheng, Jian; Sun, Xuan; Tang, Hua

    2017-02-01

    The functions of prefrontal cortex (PFC) are sensitive to norepinephrine (NE). Endogenously released NE influences synaptic transmission through activation of different subtypes of adrenergic receptors in PFC including α 1 , α 2 , β 1 or β 2 -adrenoceptor. Our recent study has revealed that β 1 -adrenoceptor (β 1 -AR) activation modulates glutamatergic transmission in the PFC, whereas the roles of β 1 -AR in GABAergic transmission are elusive. In the current study, we probed the effects of the β 1 -AR agonist dobutamine (Dobu) on GABAergic transmission onto pyramidal neurons in the PFC of juvenile rats. Dobu increased both the frequency and amplitude of miniature IPSCs (mIPSCs). Ca 2+ influx through T-type voltage-gated Ca 2+ channel was required for Dobu-enhanced mIPSC frequency. We also found that Dobu facilitated GABA release probability and the number of releasable vesicles through regulating T-type Ca 2+ channel. Dobu depolarized GABAergic fast-spiking (FS) interneurons with no effects on the firing rate of action potentials (APs) of interneurons. Dobu-induced depolarization of FS interneurons required inward rectifier K + channel (Kir). Our results suggest that Dobu increase GABA release via inhibition of Kir, which further depolarizes FS interneurons resulting in Ca 2+ influx via T-type Ca 2+ channel. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. Action of Specific Thyroid Hormone Receptor alpha(1) and beta(1) Antagonists in the Central and Peripheral Regulation of Thyroid Hormone Metabolism in the Rat

    van Beeren, Hermina C.; Kwakkel, Joan; Ackermans, Mariëtte T.; Wiersinga, Wilmar M.; Fliers, Eric; Boelen, Anita

    2012-01-01

    Background: The iodine-containing drug amiodarone (Amio) and its noniodine containing analogue dronedarone (Dron) are potent antiarrhythmic drugs. Previous in vivo and in vitro studies have shown that the major metabolite of Amio, desethylamiodarone, acts as a thyroid hormone receptor (TR) alpha(1)

  9. Immediate haemodynamic effects of a novel partial agonist, beta 1-adrenoceptor blocking drug ICI 141,292 after intravenous administration to healthy young volunteers and patients with ischaemic heart disease

    Bonde, J; Svendsen, T L; Lyngborg, K

    1987-01-01

    administration of four sequential doses (0.5, 0.5, 1.0 and 2.0 mg) of ICI 141,292 was examined. HR decreased 7% (P less than 0.05) following ICI 141,292 1 mg with no further decrease following the succeeding doses. Cardiac output decreased 5.2% (P less than 0.05) following a cumulative dose of 4 mg...... as atenolol) beta 1-adrenoceptor blocking agent possessing moderate intrinsic sympathomimetic activity....

  10. The 2.1 Å resolution structure of cyanopindolol-bound β1-adrenoceptor identifies an intramembrane Na+ ion that stabilises the ligand-free receptor.

    Jennifer L Miller-Gallacher

    Full Text Available The β1-adrenoceptor (β1AR is a G protein-coupled receptor (GPCR that is activated by the endogenous agonists adrenaline and noradrenaline. We have determined the structure of an ultra-thermostable β1AR mutant bound to the weak partial agonist cyanopindolol to 2.1 Å resolution. High-quality crystals (100 μm plates were grown in lipidic cubic phase without the assistance of a T4 lysozyme or BRIL fusion in cytoplasmic loop 3, which is commonly employed for GPCR crystallisation. An intramembrane Na+ ion was identified co-ordinated to Asp872.50, Ser1283.39 and 3 water molecules, which is part of a more extensive network of water molecules in a cavity formed between transmembrane helices 1, 2, 3, 6 and 7. Remarkably, this water network and Na+ ion is highly conserved between β1AR and the adenosine A2A receptor (rmsd of 0.3 Å, despite an overall rmsd of 2.4 Å for all Cα atoms and only 23% amino acid identity in the transmembrane regions. The affinity of agonist binding and nanobody Nb80 binding to β1AR is unaffected by Na+ ions, but the stability of the receptor is decreased by 7.5°C in the absence of Na+. Mutation of amino acid side chains that are involved in the co-ordination of either Na+ or water molecules in the network decreases the stability of β1AR by 5-10°C. The data suggest that the intramembrane Na+ and associated water network stabilise the ligand-free state of β1AR, but still permits the receptor to form the activated state which involves the collapse of the Na+ binding pocket on agonist binding.

  11. Anxiolytic-like and antidepressant-like activities of MCL0129 (1-[(S)-2-(4-fluorophenyl)-2-(4-isopropylpiperadin-1-yl)ethyl]-4-[4-(2-methoxynaphthalen-1-yl)butyl]piperazine), a novel and potent nonpeptide antagonist of the melanocortin-4 receptor.

    Chaki, Shigeyuki; Hirota, Shiho; Funakoshi, Takeo; Suzuki, Yoshiko; Suetake, Sayoko; Okubo, Taketoshi; Ishii, Takaaki; Nakazato, Atsuro; Okuyama, Shigeru

    2003-02-01

    We investigated the effects of a novel melanocortin-4 (MC4) receptor antagonist,1-[(S)-2-(4-fluorophenyl)-2-(4-isopropylpiperadin-1-yl)ethyl]-4-[4-(2-methoxynaphthalen-1-yl)butyl]piperazine (MCL0129) on anxiety and depression in various rodent models. MCL0129 inhibited [(125)I][Nle(4)-D-Phe(7)]-alpha-melanocyte-stimulating hormone (alpha-MSH) binding to MC4 receptor with a K(i) value of 7.9 nM, without showing affinity for MC1 and MC3 receptors. MCL0129 at 1 microM had no apparent affinity for other receptors, transporters, and ion channels related to anxiety and depression except for a moderate affinity for the sigma(1) receptor, serotonin transporter, and alpha(1)-adrenoceptor, which means that MCL0129 is selective for the MC4 receptor. MCL0129 attenuated the alpha-MSH-increased cAMP formation in COS-1 cells expressing the MC4 receptor, whereas MCL0129 did not affect basal cAMP levels, thereby indicating that MCL0129 acts as an antagonist at the MC4 receptor. Swim stress markedly induced anxiogenic-like effects in both the light/dark exploration task in mice and the elevated plus-maze task in rats, and MCL0129 reversed the stress-induced anxiogenic-like effects. Under nonstress conditions, MCL0129 prolonged time spent in the light area in the light/dark exploration task and suppressed marble-burying behavior. MCL0129 shortened immobility time in the forced swim test and reduced the number of escape failures in inescapable shocks in the learned helplessness test, thus indicating an antidepressant potential. In contrast, MCL0129 had negligible effects on spontaneous locomotor activity, Rotarod performance, and hexobarbital-induced anesthesia. These observations indicate that MCL0129 is a potent and selective MC4 antagonist with anxiolytic- and antidepressant-like activities in various rodent models. MC4 receptor antagonists may prove effective for treating subjects with stress-related disorders such as depression and/or anxiety.

  12. In vitro study on the effects of some selected agonists and antagonists of alpha(1)-adrenergic receptors on the contractility of the aneurysmally-changed aortic smooth muscle in humans.

    Gnus, J; Czerski, A; Ferenc, S; Zawadzki, W; Witkiewicz, W; Hauzer, W; Rusiecka, A; Bujok, J

    2012-02-01

    The study included 18 sections of the aneurysmally-changed abdominal aortas, obtained from patients of the Provincial Specialist Hospital in Wroclaw and 18 sections of normal abdominal aortas obtained from swine. The collected samples were placed horizontally in the incubation chamber. Changes in their transverse section area were registered. They were stretched to a tension of 5 mN. Krebs-Henseleit buffer was used as the incubatory environment. Incubation of the sections was performed at a temperature of 37°C, in the gaseous mixture of oxygen and carbon dioxide used in the following proportion: 95% of O(2) and 5% of CO(2). Contractions of the aorta were registered with isotonic transducers (Letica Scientific Instruments). In the studies, we examined the influence of α(1)-adrenergic receptors (and their subtypes α(1A), α(1B), α(1D)) on the contractility of the aortic muscle in humans and swine by their stimulation or inhibition with some selected agonists or antagonists. This time, it was shown that the stimulation of α(1)-adrenergic receptors leads to contractions of the human and swine aortic muscle; the observed increase in the muscle tone may follow from the stimulation of all subtypes of alpha-1 receptor (α(1A), α(1B), α(1D)). All three subtypes of 1-adrenergic receptor are engaged in vasoconstriction, especially of α(1A) and α(1D) subtypes; the α(1B) subtype is less significant for aortic contractility. The contractile response of the aneurysmally-changed abdominal aorta in humans to agonists of α-adrenergic receptors was significantly less intense than that of the normal porcine aorta. It can be concluded that aneurysms influence the contractile response of the aorta.

  13. ACTH antagonists

    Adrian John Clark

    2016-08-01

    Full Text Available ACTH acts via a highly selective receptor that is a member of the melanocortin receptor subfamily of type 1 G protein-coupled receptors. The ACTH receptor, also known as the melanocortin 2 receptor (MC2R is unusual in that it is absolutely dependent on a small accessory protein, melanocortin receptor accessory protein (MRAP for cell surface expression and function. ACTH is the only known naturally occurring agonist for this receptor. This lack of redundancy and high degree of ligand specificity suggests that antagonism of this receptor could provide a useful therapeutic aid and a potential investigational tool. Clinical situations in which this could be useful include (1 Cushing’s disease and ectopic ACTH syndrome – especially whilst preparing for definitive treatment of a causative tumour, or in refractory cases, or (2 congenital adrenal hyperplasia – as an adjunct to glucocorticoid replacement. A case for antagonism in other clinical situations in which there is ACTH excess can also be made. In this article we will explore the scientific and clinical case for an ACTH antagonist, and will review the evidence for existing and recently described peptides and modified peptides in this role.

  14. Afferent Pathway-Mediated Effect of α1 Adrenergic Antagonist, Tamsulosin, on the Neurogenic Bladder After Spinal Cord Injury.

    Han, Jin-Hee; Kim, Sung-Eun; Ko, Il-Gyu; Kim, Jayoung; Kim, Khae Hawn

    2017-09-01

    The functions of the lower urinary tract (LUT), such as voiding and storing urine, are dependent on complex central neural networks located in the brain, spinal cord, and peripheral ganglia. Thus, the functions of the LUT are susceptible to various neurologic disorders including spinal cord injury (SCI). SCI at the cervical or thoracic levels disrupts voluntary control of voiding and the normal reflex pathways coordinating bladder and sphincter functions. In this context, it is noteworthy that α1-adrenoceptor blockers have been reported to relieve voiding symptoms and storage symptoms in elderly men with benign prostatic hyperplasia (BPH). Tamsulosin, an α1-adrenoceptor blocker, is also considered the most effective regimen for patients with LUT symptoms such as BPH and overactive bladder (OAB). In the present study, the effects of tamsulosin on the expression of c-Fos, nerve growth factor (NGF), and nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d) in the afferent micturition areas, including the pontine micturition center (PMC), the ventrolateral periaqueductal gray matter (vlPAG), and the spinal cord (L5), of rats with an SCI were investigated. SCI was found to remarkably upregulate the expression of c-Fos, NGF, and NADPH-d in the afferent pathway of micturition, the dorsal horn of L5, the vlPAG, and the PMC, resulting in the symptoms of OAB. In contrast, tamsulosin treatment significantly suppressed these neural activities and the production of nitric oxide in the afferent pathways of micturition, and consequently, attenuated the symptoms of OAB. Based on these results, tamsulosin, an α1-adrenoceptor antagonist, could be used to attenuate bladder dysfunction following SCI. However, further studies are needed to elucidate the exact mechanism and effects of tamsulosin on the afferent pathways of micturition.

  15. Efficacy and safety of tamsulosin in the treatment of urological diseases

    Michel, Martin C.; de La Rosette, Jean J. M. C. H.

    2004-01-01

    The alpha(1)-adrenoceptor antagonist tamsulosin, is selective for alpha(1A)- and alpha(1D)-over alpha(1B)-adrenoceptors. Both placebo-controlled and comparative studies with other agents have demonstrated tamsulosin to be an effective treatment for patients with lower urinary symptoms suggestive of

  16. The Effect of Sympathetic Antagonists on the Antidepressant Action of Alprazolam

    Gorash ZM

    2008-01-01

    Full Text Available Alprazolam is an anti-anxiety drug shown to be effective in the treatment of depression. In this study, the effect of sympathetic receptor antagonists on alprazolam–induced antidepressant action was studied using a mouse model of forced swimming behavioral despair. The interaction of three sympathetic receptor antagonists with benzodiazepines, which may impact the clinical use of alprazolam, was also studied. Behavioral despair was examined in six groups of albino mice. Drugs were administered intraperitoneally. The control group received only a single dose of 1% Tween 80. The second group received a single dose of alprazolam, and the third group received an antagonist followed by alprazolam. The fourth group was treated with imipramine, and the fifth group received an antagonist followed by imipramine. The sixth group was treated with a single dose of an antagonist alone (atenolol, a β1-selective adrenoceptor antagonist; propranolol, a non selective β-adrenoceptor antagonist; and prazocin, an α1-adrenoceptor antagonist. Results confirmed the antidepressant action of alprazolam and imipramine. Prazocin treatment alone produced depression, but it significantly potentiated the antidepressant actions of imipramine and alprazolam. Atenolol alone produced an antidepressant effect and potentiated the antidepressant action of alprazolam. Propranolol treatment alone produced depression, and antagonized the effects of alprazolam and imipramine, even producing depression in combined treatments. In conclusion, our results reveal that alprazolam may produce antidepressant effects through the release of noradrenaline, which stimulates β2 receptors to produce an antidepressant action. Imipramine may act by activating β2 receptors by blocking or down-regulating β1 receptors.

  17. β1-Adrenoceptor autoantibodies from DCM patients enhance the proliferation of T lymphocytes through the β1-AR/cAMP/PKA and p38 MAPK pathways.

    Yunhui Du

    Full Text Available Autoantibodies against the second extracellular loop of the β(1-adrenergic receptor (β(1-AA not only contribute to increased susceptibility to heart failure, but also play a causative role in myocardial remodeling through their sympathomimetic-like effects that are induced upon binding to the β(1-adrenergic receptor. However, their role in the function of T lymphocytes has never been previously investigated. Our present study was designed to determine whether β(1-AA isolated from the sera of dilated cardiomyopathy (DCM patients caused the proliferation of T cells and the secretion of cytokines.Blood samples were collected from 95 DCM patients as well as 95 healthy subjects, and β(1-AA was detected using ELISA. The CD3(+T lymphocytes were selected separately through flow cytometry and the effect of β(1-AA on T lymphocyte proliferation was examined by CCK-8 kits and CFSE assay. Western blotting was used to analyze the expressions of phospho-VASP and phospho-p38 MAPK.β(1-AA enhanced the proliferation of T lymphocytes. This effect could be blocked by the selective β(1-adrenergic receptor antagonist metoprolol, PKA inhibitor H89, and p38 MAPK inhibitor SB203580. Furthermore, the expression of the phosphorylated forms of phospho-VASP and phospho-p38 MAPK were markedly increased in the presence of β(1-AA. β(1-AA also inhibited the secretion of interferon-γ (IFN-γ while promoting an increase in interleukin-4 (IL-4 levels.These results demonstrate that β(1-AA isolated from DCM patients binds to β(1-AR on the surface of T cells, causing changes in T-cell proliferation and secretion through the β(1-AR/cAMP/PKA and p38 MAPK pathways.

  18. Synthesis and serotonergic activity of substituted 2, N-benzylcarboxamido-5-(2-ethyl-1-dioxoimidazolidinyl)-N, N-dimethyltryptamine derivatives: novel antagonists for the vascular 5-HT(1B)-like receptor.

    Moloney, G P; Martin, G R; Mathews, N; Milne, A; Hobbs, H; Dodsworth, S; Sang, P Y; Knight, C; Williams, M; Maxwell, M; Glen, R C

    1999-07-15

    The synthesis and vascular 5-HT(1B)-like receptor activity of a novel series of substituted 2, N-benzylcarboxamido-5-(2-ethyl-1-dioxoimidazolidinyl)-N, N-dimethyltryptamine derivatives are described. Modifications to the 5-ethylene-linked heterocycle and to substituents on the 2-benzylamide side chain have been explored. Several compounds were identified which exhibited affinity at the vascular 5-HT(1B)-like receptor of pK(B) > 7.0, up to 100-fold selectivity over alpha(1)-adrenoceptor affinity and 5-HT(2A) receptor affinity, and which exhibited a favorable pharmacokinetic profile. N-Benzyl-3-[2-(dimethylamino)ethyl]-5-[2-(4,4-dimethyl-2, 5-dioxo-1-imidazolidinyl)ethyl]-1H-indole-2-carboxamide (23) was identified as a highly potent, silent (as judged by the inability of angiotensin II to unmask 5-HT(1B)-like receptor-mediated agonist activity in the rabbit femoral artery), and competitive vascular 5-HT(1B)-like receptor antagonist with a plasma elimination half-life of approximately 4 h in dog plasma and with good oral bioavailability. The selectivity of compounds from this series for the vascular 5-HT(1B)-like receptors over other receptor subtypes is discussed as well as a proposed mode of binding to the receptor pharmacophore. It has been proposed that the aromatic ring of the 2, N-benzylcarboxamide group can occupy an aromatic binding site rather than the indole ring. The resulting conformation allows an amine-binding site to be occupied by the ethylamine nitrogen and a hydrogen-bonding site to be occupied by one of the hydantoin carbonyls. The electronic nature of the 2,N-benzylcarboxamide aromatic group as well as the size of substituents on this aromatic group is crucial for producing potent and selective antagonists. The structural requirement on the 3-ethylamine side chain incorporating the protonatable nitrogen is achieved by the bulky 2, N-benzylcarboxamide group and its close proximity to the 3-side chain.

  19. Small molecule antagonists of integrin receptors.

    Perdih, A; Dolenc, M Sollner

    2010-01-01

    The complex and widespread family of integrin receptors is involved in numerous physiological processes, such as tissue remodeling, angiogenesis, development of the immune response and homeostasis. In addition, their key role has been elucidated in important pathological disorders such as cancer, cardiovascular diseases, osteoporosis, autoimmune and inflammatory diseases and in the pathogenesis of infectious diseases, making them highly important targets for modern drug design campaigns. In this review we seek to present a concise overview of the small molecule antagonists of this diverse and highly complex receptor family. Integrin antagonists are classified according to the targeted integrin receptor and are discussed in four sections. First we present the fibrinogen alpha(IIb)beta3 and the vitronectin alpha (V)beta(3) receptor antagonists. The remaining selective integrin antagonists are examined in the third section. The final section is dedicated to molecules with dual or multiple integrin activity. In addition, the use of antibodies and peptidomimetic approaches to modulate the integrin receptors are discussed, as well providing the reader with an overall appreciation of the field.

  20. Alpha 1 B- but not alpha 1 A-adrenoceptors mediate inositol phosphate generation

    Michel, M. C.; Hanft, G.; Gross, G.

    1990-01-01

    We used novel highly subtype-selective antagonists to study whether alpha 1A- and/or alpha 1B-adrenoceptors mediate the stimulation of inositol phosphate generation by noradrenaline in rat cerebral cortex. Phentolamine (10 microM) and prazosin (100 nM) completely abolished the stimulated inositol

  1. Potentiation of the isoproterenol-induced net /sup 45/Ca uptake into the ventricular myocardium of rats by means of 9. cap alpha. -fluorocortisoleacetate, dihydrotachysterole or NaH/sub 2/PO/sub 4/. Cancelling of the potentiation by organic Ca/sup 2 +/ antagonists or K/sup +/ and Mg/sup 2 +/ ions

    Hein, R

    1974-01-01

    Myocardial necroses resembling infarctions as well as disseminated myocardial necroses can be induced in rats by high doses of isoprotenerol which effects a maximum stimulation of the decomposition of energy-rich phosphate. This leads to an isoprotenerol-induced increase of the transmembranous Ca/sup + +/ influx, flooding the myocardium with Ca/sup + +/ ions. It is these Ca/sup + +/ ions which then trigger the break-down of the ATP and creatine phosphate fractions by activating the myofibrit-ATPase and impairing the mitochondrial function. It seems that physiological Ca/sup + +/ antagonists such as K/sup +/- or Mg/sup + +/-salts counteract the loss of energy-rich phosphate, thus preventing necroses. A new group of organic Ca/sup + +/ antagonists (verapamil, substance D 600, prenylamine) appears to be even more effective in this respect. Given in appropriate doses, these substances may prevent the isoprotenerol-induced Ca/sup + +/ flooding of the myocardium to a large extent, so that a break-down of the ATP and creatine phosphate fractions is avoided. On the other hand, the isoprotenerol-induced increase of the Ca/sup + +/ influx may be further potentiated by a preliminary treatment of the animals with 9..cap alpha..-fluorocortisoleacetate, dihydrotachysterole or NaH/sub 2/PO/sub 4/. This results in an extreme loss of energy-rich phosphate from the myocardium with excessive enhancement of necrosis production. The findings suggest that - unrecognized so far - Ca/sup + +/ ions play a key role in the generation of myocardial necroses: the present assumption, according to which increased Ca/sup + +/ uptake into damaged myocardial fibres is only a result - or at the most an accompanying symptom - of necrosis can thus no longer be considered valid.

  2. Investigation of the effect of mutations of rat albumin on the binding affinity to the alpha(4)beta(1) integrin antagonist, 4-[1-[3-chloro-4-[N'-(2-methylphenyl)ureido]phenylacetyl]-(4S)-fluoro-(2S)-pyrrolidine-2-yl]methoxybenzoic acid (D01-4582), using recombinant rat albumins.

    Ito, Takashi; Takahashi, Masayuki; Okazaki, Osamu; Sugiyama, Yuichi

    2010-08-02

    The authors reported previously rat strain differences in plasma protein binding to alpha(4)beta(1) antagonist D01-4582, resulting in a great strain difference in its pharmacokinetics (19-fold differences in the AUC). The previous study suggested that amino acid changes of V238L and/or T293I in albumin reduced the binding affinity. In order to elucidate the relative significance of these mutations, an expression system was developed to obtain recombinant rat albumins (rRSA) using Pichia pastoris, followed by a binding analysis of four rRSAs by the ultracentrifugation method. The equilibrium dissociation constant (K(d)) of wild-type rRSA was 210 nM, while K(d) of rRSA that carried both V238L and T293I mutations was 974 nM. K(d) of artificial rRSA that carried only V238L was 426 nM, and K(d) of artificial rRSA that carried only T293I was 191 nM. These results suggested that V238L would be more important in the alteration of K(d). However, since none of the single mutations were sufficient to explain the reduction of affinity, the possibility was also suggested that T293I interacted cooperatively to reduce the binding affinity of rat albumin to D01-4582. Further investigation is required to elucidate the mechanism of the possible cooperative interaction.

  3. Radiation dosimetry of iodine-123 HEAT, an alpha-1 receptor imaging agent

    Thomas, K.D.; Greer, D.M.; Couch, M.W.; Williams, C.M.

    1987-01-01

    Biologic distribution data in the rat were obtained for the alpha-1 adrenoceptor imaging agent (+/-) 2-[beta-(iodo-4-hydroxyphenyl)ethylaminomethyl]tetralone (HEAT) labeled with [ 123 I]. The major excretory routes were through the liver (67%) and the kidney (33%). Internal radiation absorbed dose estimates to nine source organs, total body, the GI tract, gonads, and red bone marrow were calculated for the human using the physical decay data for [ 123 I]. The critical organ was found to be the lower large intestine, receiving 1.1 rad per mCi of [ 123 I]HEAT administered. The total-body dose was found to be 58 mrad per mCi

  4. Pharmacokinetics and Pharmacodynamics of Tamsulosin in its Modified-Release and Oral Controlled Absorption System Formulations

    Franco-Salinas, Gabriela; de La Rosette, Jean J. M. C. H.; Michel, Martin C.

    2010-01-01

    Tamsulosin is an alpha(1)-adrenoceptor antagonist used for the treatment of lower urinary tract symptoms that are suggestive of benign prostatic hyperplasia. It is mostly used in a modified-release (M R) Formulation. but an oral controlled absorption system (OCAS) and a 'without-water' tablet

  5. Dual antagonists of integrins.

    Nadrah, K; Dolenc, M Sollner

    2005-01-01

    The roles of integrins in pathologies have been studied intensively and only partially explained. This has resulted in the development of several nanomolar antagonists to certain integrins. In most cases, the aim was to produce compounds which are highly selective towards specific integrins. This paradigm has recently shifted a little. Targeting two or more integrins with one compound has become a very attractive concept, especially since it has become clear that several severe disorders, such as pathological angiogenesis, cannot be treated just with highly specific integrin antagonists. This review is aimed to elucidate some aspects regarding the design of drugs with dual activity towards integrins. Integrin structure and tissue distribution will first be described, in order to provide the basis for their functions in various pathologies which will follow. Inhibitors of several pairs of integrins will be described.

  6. Buffett's Alpha

    Frazzini, Andrea; Kabiller, David; Heje Pedersen, Lasse

    Berkshire Hathaway has realized a Sharpe ratio of 0.76, higher than any other stock or mutual fund with a history of more than 30 years, and Berkshire has a significant alpha to traditional risk factors. However, we find that the alpha becomes insignificant when controlling for exposures to Betting...

  7. Alpha Blockers

    ... quickly, but their effects last only a few hours. Long-acting medications take longer to work, but their effects last longer. Which alpha blocker is best for you depends on your health and the condition being treated. Alpha blockers are ...

  8. Inhibition of Brain Swelling after Ischemia-Reperfusion by β-Adrenergic Antagonists: Correlation with Increased K+ and Decreased Ca2+ Concentrations in Extracellular Fluid

    Dan Song

    2014-01-01

    Full Text Available Infarct size and brain edema following ischemia/reperfusion are reduced by inhibitors of the Na+, K+, 2Cl−, and water cotransporter NKCC1 and by β1-adrenoceptor antagonists. NKCC1 is a secondary active transporter, mainly localized in astrocytes, driven by transmembrane Na+/K+ gradients generated by the Na+,K+-ATPase. The astrocytic Na+,K+-ATPase is stimulated by small increases in extracellular K+ concentration and by the β-adrenergic agonist isoproterenol. Larger K+ increases, as occurring during ischemia, also stimulate NKCC1, creating cell swelling. This study showed no edema after 3 hr medial cerebral artery occlusion but pronounced edema after 8 hr reperfusion. The edema was abolished by inhibitors of specifically β1-adrenergic pathways, indicating failure of K+-mediated, but not β1-adrenoceptor-mediated, stimulation of Na+,K+-ATPase/NKCC1 transport during reoxygenation. Ninety percent reduction of extracellular Ca2+ concentration occurs in ischemia. Ca2+ omission abolished K+ uptake in normoxic cultures of astrocytes after addition of 5 mM KCl. A large decrease in ouabain potency on K+ uptake in cultured astrocytes was also demonstrated in Ca2+-depleted media, and endogenous ouabains are needed for astrocytic K+ uptake. Thus, among the ionic changes induced by ischemia, the decrease in extracellular Ca2+ causes failure of the high-K+-stimulated Na+,K+-ATPase/NKCC1 ion/water uptake, making β1-adrenergic activation the only stimulus and its inhibition effective against edema.

  9. Human myometrial adrenergic receptors during pregnancy: identification of the alpha-adrenergic receptor by [3H] dihydroergocryptine binding

    Jacobs, M.M.; Hayashida, D.; Roberts, J.M.

    1985-01-01

    The radioactive alpha-adrenergic antagonist [ 3 H] dihydroergocryptine binds to particulate preparations of term pregnant human myometrium in a manner compatible with binding to the alpha-adrenergic receptor (alpha-receptor). [ 3 H] Dihydroergocryptine binds with high affinity (KD = 2 nmol/L and low capacity (receptor concentration = 100 fmol/mg of protein). Adrenergic agonists compete for [ 3 H] dihydroergocryptine binding sites stereo-selectively ([-]-norepinephrine is 100 times as potent as [+]-norepinephrine) and in a manner compatible with alpha-adrenergic potencies (epinephrine approximately equal to norepinephrine much greater than isoproterenol). Studies in which prazosin, an alpha 1-antagonist, and yohimbine, and alpha 2-antagonist, competed for [ 3 H] dihydroergocryptine binding sites in human myometrium indicated that approximately 70% are alpha 2-receptors and that 30% are alpha 1-receptors. [ 3 H] dihydroergocryptine binding to human myometrial membrane particulate provides an important tool with which to study the molecular mechanisms of uterine alpha-adrenergic response

  10. Effect of alpha1-blockers on stentless ureteroscopic lithotripsy

    Jianguo Zhu

    2016-02-01

    Full Text Available ABSTRACT Objective To evaluate the clinical efficiency of alpha1-adrenergic antagonists on stentless ureteroscopic lithotripsy treating uncomplicated lower ureteral stones. Materials and Methods From January 2007 to January 2013, 84 patients who have uncomplicated lower ureteral stones treated by ureteroscopic intracorporeal lithotripsy with the holmium laser were analyzed. The patients were divided into two groups, group A (44 patients received indwelled double-J stents and group B (40 patients were treated by alpha1-adrenergic antagonists without stents. All cases of group B were treated with alpha1 blocker for 1 week. Results The mean operative time of group A was significantly longer than group B. The incidences of hematuria, flank/abdominal pain, frequency/urgency after surgery were statistically different between both groups. The stone-free rate of each group was 100%. Conclusions The effect of alpha1-adrenergic antagonists is more significant than indwelling stent after ureteroscopic lithotripsy in treating uncomplicated lower ureteral stones.

  11. Interaction of selected vasodilating beta-blockers with adrenergic receptors in human cardiovascular tissues

    Monopoli, A.; Forlani, A.; Bevilacqua, M.; Vago, T.; Norbiato, G.; Bertora, P.; Biglioli, P.; Alamanni, F.; Ongini, E.

    1989-01-01

    beta- And alpha 1-adrenoceptor antagonist properties of bufuralol, carvedilol, celiprolol, dilevalol, labetalol, and pindolol were investigated in human myocardium and mammary artery using binding techniques and functional studies. In myocardial membranes, beta-adrenoceptor antagonists showed monophasic competition isotherms for [125I]pindolol binding with high affinity (Ki from 1-100 nM), except for celiprolol which displayed a biphasic competition isotherm (pKi = 6.4 +/- 0.06 for beta 1- and 4.8 +/- 0.07 for beta 2-adrenoceptors). Drug interactions with alpha 1-adrenoceptors were evaluated in human mammary artery by [3H]prazosin binding and by measuring contractile responses to norepinephrine (NE). Labetalol and carvedilol showed a moderate affinity for alpha 1-adrenoceptors (pKi = 6.2 +/- 0.01 and 6.1 +/- 0.06, respectively), and inhibited NE-induced contractions (pA2 = 6.93 +/- 0.23 and 8.64 +/- 0.24, respectively). Dilevalol, bufuralol, and pindolol displayed weak effect both in binding (Ki in micromolar range) and functional experiments (pA2 = 5.98, 5.54, and 6.23, respectively). Celiprolol did not show antagonist properties up to 100 microM in functional studies, but displayed a slight affinity for alpha 1-adrenoceptors in binding studies. The data indicate that the vasodilating activity of these beta-adrenoceptor antagonists is caused in some instances by an alpha 1-adrenoceptor antagonism (labetalol, carvedilol), whereas for the others alternative mechanisms should be considered

  12. Anti-tumor necrosis factor-alpha therapies attenuate adaptive arteriogenesis in the rabbit

    Grundmann, Sebastian; Hoefer, Imo; Ulusans, Susann; van Royen, Niels; Schirmer, Stephan H.; Ozaki, C. Keith; Bode, Christoph; Piek, Jan J.; Buschmann, Ivo

    2005-01-01

    The specific antagonists of tumor necrosis factor-alpha (TNF-alpha), infliximab and etanercept, are established therapeutic agents for inflammatory diseases such as rheumatoid arthritis and Crohn's disease. Although the importance of TNF-alpha in chronic inflammatory diseases is well established,

  13. Naloxone : actions of an antagonist

    Dorp, Eveline Louise Arianna van

    2009-01-01

    The opioid antagonist naloxone has a special place in pharmacology – it has no intrinsic action of its own, but it is able to save lives in the case of life threatening side-effects caused by other drugs. Naloxone is an antagonist for all opioid receptors, but most specifically for the μ-opioid

  14. Carbon adaptation influence the antagonistic ability of ...

    Jane

    2011-10-24

    Oct 24, 2011 ... INTRODUCTION. The use of antagonistic bacteria to control soil-borne ... plant was used to evaluate the antifungal activities of antagonistic bacteria. ..... antagonistic bacteria and cloning of its phenazine carboxylic acid genes.

  15. Correlation between phosphatidylinositol labeling and contraction in rabbit aorta: effect of alpha-1 adrenergic activation

    Villalobos-Molina, R.; Uc, M.; Hong, E.; Garcia-Sainz, J.A.

    1982-01-01

    Activation of rabbit aortic strips with alpha adrenergic agonists increased the labeling (with [ 32 P]Pi) of phosphatidylinositol (PI) and phosphatidic acid and contracted the vascular preparations in dose-related fashion. Epinephrine, norepinephrine and methoxamine produced maximal effects, whereas clonidine behaved as partial agonist and B-HT 933 (2-amino-6-ethyl-4,5,7,8-tetrahydro-6H-oxazole-[5,4-d] azepin dihydrochloride) was almost without activity in the two experimental models used. Phenylephrine was a full agonist in producing contraction, but failed to elicit the maximal increase in PI labeling. The EC50 values to produce contraction of aortic strips were lower for all agonists than those required to increase the incorporation of radioactive phosphate into PI, but there was a good correlation between the two sets of data. The increased PI labeling and contraction of aortic strips induced by epinephrine were antagonized by prazosin and yohimbine in dose-related fashion, but the first alpha blocker was about three orders of magnitude more potent than the second in antagonizing the two effects. The present results indicate that both stimulation of PI labeling and contraction are mediated through activation of alpha-1 adrenoceptors in rabbit aorta

  16. Modification of certain pharmacological effects of ethanol by lipophilic alpha-1 adrenergic agonists

    Menon, M.K.; Dinovo, E.C.; Haddox, V.G.

    1987-09-28

    The influence of four centrally-acting alpha-1 adrenoceptor agonists, namely, 2(2-chloro-5-trifluoromethylphenylimino) imidazolidine (St 587), cirazoline, (-) 1,2,3,4-tetrahydro-8-methoxy-5-methylthio-2-naphthalenamine ((-)SKF 89748A) and 2-(2-methylindazol-4-imino)imidazolidine (Sgd 101/75) on the pharmacological effects of ethanol was investigated. All four drugs reduced the duration of ethanol-induced hypnosis in C57B1/6 mice, this effect being proportional to their relative potencies to exert central alpha-1 agonism. In prazosin-pretreated mice, St 587 failed to reduce the hypnotic effect of ethanol, which provided strong evidence for the role of alpha-1 agonism for the hypnosis reducing effect of St 587. Hyperactivity induced in C57B1/6 mice by a subhypnotic dose of ethanol and St 587 was reported earlier. In the present study, St 587, cirazoline and (-)SKF 89748A produced similar response, but no correlation between this effect and ethanol hypnosis blockade could be established. 19 references, 8 figures, 2 tables.

  17. Interaction between Antagonist of Cannabinoid Receptor and Antagonist of Adrenergic Receptor on Anxiety in Male Rat

    Alireza Komaki

    2014-07-01

    Full Text Available Introduction: Anxiety is among the most common and treatable mental disorders. Adrenergic and cannabinoid systems have an important role in the neurobiology of anxiety. The elevated plus-maze (EPM has broadly been used to investigate anxiolytic and anxiogenic compounds. The present study investigated the effects of intraperitoneal (IP injection of cannabinoid CB1 receptor antagonist (AM251 in the presence of alpha-1 adrenergic antagonist (Prazosin on rat behavior in the EPM. Methods: In this study, the data were obtained from male Wistar rat, which weighing 200- 250 g. Animal behavior in EPM were videotaped and saved in computer for 10 min after IP injection of saline, AM251 (0.3 mg/kg, Prazosin (0.3 mg/kg and AM251 + Prazosin, subsequently scored for conventional indices of anxiety. During the test period, the number of open and closed arms entries, the percentage of entries into the open arms of the EPM, and the spent time in open and closed arms were recorded. Diazepam was considered as a positive control drug with anxiolytic effect (0.3, 0.6, 1.2 mg/kg. Results: Diazepam increased the number of open arm entries and the percentage of spent time on the open arms. IP injection of AM251 before EPM trial decreased open arms exploration and open arm entry. Whereas, Prazosin increased open arms exploration and open arm entry. This study showed that both substances in simultaneous injection have conflicting effects on the responses of each of these two compounds in a single injection. Discussion: Injection of CB1 receptor antagonist may have an anxiogenic profile in rat, whereas adrenergic antagonist has an anxiolytic effect. Further investigations are essential for better understanding of anxiolytic and anxiogenic properties and neurobiological mechanisms of action and probable interactions of the two systems.

  18. Interaction between Antagonist of Cannabinoid Receptor and Antagonist of Adrenergic Receptor on Anxiety in Male Rat.

    Komaki, Alireza; Abdollahzadeh, Fatemeh; Sarihi, Abdolrahman; Shahidi, Siamak; Salehi, Iraj

    2014-01-01

    Anxiety is among the most common and treatable mental disorders. Adrenergic and cannabinoid systems have an important role in the neurobiology of anxiety. The elevated plus-maze (EPM) has broadly been used to investigate anxiolytic and anxiogenic compounds. The present study investigated the effects of intraperitoneal (IP) injection of cannabinoid CB1 receptor antagonist (AM251) in the presence of alpha-1 adrenergic antagonist (Prazosin) on rat behavior in the EPM. In this study, the data were obtained from male Wistar rat, which weighing 200- 250 g. Animal behavior in EPM were videotaped and saved in computer for 10 min after IP injection of saline, AM251 (0.3 mg/kg), Prazosin (0.3 mg/kg) and AM251 + Prazosin, subsequently scored for conventional indices of anxiety. During the test period, the number of open and closed arms entries, the percentage of entries into the open arms of the EPM, and the spent time in open and closed arms were recorded. Diazepam was considered as a positive control drug with anxiolytic effect (0.3, 0.6, 1.2 mg/kg). Diazepam increased the number of open arm entries and the percentage of spent time on the open arms. IP injection of AM251 before EPM trial decreased open arms exploration and open arm entry. Whereas, Prazosin increased open arms exploration and open arm entry. This study showed that both substances in simultaneous injection have conflicting effects on the responses of each of these two compounds in a single injection. Injection of CB1 receptor antagonist may have an anxiogenic profile in rat, whereas adrenergic antagonist has an anxiolytic effect. Further investigations are essential for better understanding of anxiolytic and anxiogenic properties and neurobiological mechanisms of action and probable interactions of the two systems.

  19. ANTAGONISTIC POTENTIAL OF FLUORESCENT Pseudomonas ...

    Prof. Adipala Ekwamu

    GROWTH OF TOMATO CHALLENGED WITH PHTOPATHOGENS ... This study focused on the antagonistic potential of fluorescent Pseudomonas in vitro, and its inoculation effect on growth .... the 5 days old culture in starch agar with Lugol's.

  20. IL-1 Receptor Antagonist Chimeric Protein: Context-Specific and Inflammation-Restricted Activation

    Rider, P.; Carmi, Y.; Yossef, R.; Guttman, O.; Eini, H.; Azam, T.; Dinarello, C.A.; Lewis, E.C.

    2015-01-01

    Both IL-1alpha and IL-1beta are highly inflammatory cytokines mediating a wide spectrum of diseases. A recombinant form of the naturally occurring IL-1R antagonist (IL-1Ra), which blocks IL-1R1, is broadly used to treat autoimmune and autoinflammatory diseases; however, blocking IL-1 increases the

  1. A Comparison of the Anorectic Effect and Safety of the Alpha2-Adrenoceptor Ligands Guanfacine and Yohimbine in Rats with Diet-Induced Obesity.

    Magdalena Dudek

    Full Text Available The search for drugs with anorectic activity, acting within the adrenergic system has attracted the interest of researchers. Partial α2-adrenoceptor agonists might offer the potential for effective and safe treatment of obesity. We compared the effectiveness and safety of α2-adrenoceptor ligands in reducing body mass. We also analyzed if antagonist and partial agonists of α2-adrenoceptor--yohimbine and guanfacine--act similarly, and determined which course of action is connected with anorectic activity. We tested intrinsic activity and effect on the lipolysis of these compounds in cell cultures, evaluated their effect on meal size, body weight in Wistar rats with high-fat diet-induced obesity, and determined their effect on blood pressure, heart rate, lipid profile, spontaneous locomotor activity, core temperature and glucose, as well as glycerol and cortisol levels. Both guanfacine and yohimbine showed anorectic activity. Guanfacine was much more effective than yohimbine. Both significantly reduced the amount of intraperitoneal adipose tissue and had a beneficial effect on lipid profiles. Decreased response of α2A-adrenoceptors and partial stimulation of α2B-receptors seem to be responsible for the anorectic action of guanfacine. The stimulation of α1-adrenoceptors by guanfacine is responsible for cardiovascular side effects but may also be linked with improved anorexic effect. α1-adrenoceptor blockade is connected with the side effects of yohimbine, but it is also associated with the improvement of lipid profiles. Guanfacine has been approved by the Food and Drug Administration (FDA to treat hypertension and conduct disorder, but as it reduces body weight, it is worth examining its effectiveness and safety in models of obesity.

  2. Excitatory amino acid receptor antagonists

    Johansen, T N; Frydenvang, Karla Andrea; Ebert, B

    1997-01-01

    We have previously shown that (RS)-2-amino-2-(5-tert-butyl-3-hydroxyisoxazol-4-yl)acetic acid (ATAA) is an antagonist at N-methyl-D-aspartic acid (NMDA) and (RS)-2-amino-3-(3-hydroxy-5-methylisoxazol-4-yl)propionic acid (AMPA) receptors. We have now resolved ATAA via diastereomeric salt formation......)-phenylethylamine salt of N-BOC-(R)-ATAA. Like ATAA, neither (R)- nor (S)-ATAA significantly affected (IC50 > 100 microM) the receptor binding of tritiated AMPA, kainic acid, or (RS)-3-(2-carboxypiperazin-4-yl)propyl-1-phosphonic acid, the latter being a competitive NMDA antagonist. Electrophysiological experiments......, using the rat cortical wedge preparation, showed the NMDA antagonist effect as well as the AMPA antagonist effect of ATAA to reside exclusively in the (R)-enantiomer (Ki = 75 +/- 5 microM and 57 +/- 1 microM, respectively). Neither (R)- nor (S)-ATAA significantly reduced kainic acid-induced excitation...

  3. Antagonism of Lateral Amygdala Alpha1-Adrenergic Receptors Facilitates Fear Conditioning and Long-Term Potentiation

    Lazzaro, Stephanie C.; Hou, Mian; Cunha, Catarina; LeDoux, Joseph E.; Cain, Christopher K.

    2010-01-01

    Norepinephrine receptors have been studied in emotion, memory, and attention. However, the role of alpha1-adrenergic receptors in fear conditioning, a major model of emotional learning, is poorly understood. We examined the effect of terazosin, an alpha1-adrenergic receptor antagonist, on cued fear conditioning. Systemic or intra-lateral amygdala…

  4. [(35)S]-GTPgammaS autoradiography reveals alpha(2) adrenoceptor-mediated G-protein activation in amygdala and lateral septum.

    Newman-Tancredi, A; Chaput, C; Touzard, M; Millan, M J

    2000-04-03

    alpha(2)-adrenoceptor-mediated G-protein activation was examined by [(35)S]-GTPgammaS autoradiography. In alpha(2)-adrenoceptor-rich regions (amygdala, lateral septum), noradrenaline stimulated [(35)S]-GTPgammaS binding. These actions were abolished by the selective alpha(2) antagonist, atipamezole. Conversely, in caudate nucleus, which expresses few alpha(2) receptors, noradrenaline-induced stimulation was not inhibited by atipamezole, suggesting that it is not mediated by alpha(2)-adrenoceptors.

  5. Alpha2-adrenoceptor modulation of long-term potentiation elicited in vivo in rat occipital cortex.

    Mondaca, Mauricio; Hernández, Alejandro; Pérez, Hernán; Valladares, Luis; Sierralta, Walter; Fernández, Victor; Soto-Moyano, Rubén

    2004-09-24

    Pretreatment with the alpha(2)-adrenoceptor agonist clonidine (31.25, 62.5, or 125 microg/kg, i.p.) dose-dependently reduced long-term potentiation (LTP) elicited in vivo in the occipital cortex of anesthetized rats, whereas pretreatment with the alpha(2)-adrenoceptor antagonist yohimbine (0.133, 0.4, or 1.2 mg/kg, i.p.) increased neocortical LTP in a dose-dependent fashion. These effects could be related to the reported disruptive and facilitatory actions induced on memory formation by pretreatment with alpha(2)-adrenoceptor agonists and antagonists, respectively.

  6. Opioid antagonists with minimal sedation for opioid withdrawal.

    Gowing, Linda; Ali, Robert; White, Jason M

    2017-05-29

    Managed withdrawal is a necessary step prior to drug-free treatment or as the endpoint of long-term substitution treatment. To assess the effects of opioid antagonists plus minimal sedation for opioid withdrawal. Comparators were placebo as well as more established approaches to detoxification, such as tapered doses of methadone, adrenergic agonists, buprenorphine and symptomatic medications. We updated our searches of the following databases to December 2016: CENTRAL, MEDLINE, Embase, PsycINFO and Web of Science. We also searched two trials registers and checked the reference lists of included studies for further references to relevant studies. We included randomised and quasi-randomised controlled clinical trials along with prospective controlled cohort studies comparing opioid antagonists plus minimal sedation versus other approaches or different opioid antagonist regimens for withdrawal in opioid-dependent participants. We used standard methodological procedures expected by Cochrane. Ten studies (6 randomised controlled trials and 4 prospective cohort studies, involving 955 participants) met the inclusion criteria for the review. We considered 7 of the 10 studies to be at high risk of bias in at least one of the domains we assessed.Nine studies compared an opioid antagonist-adrenergic agonist combination versus a treatment regimen based primarily on an alpha 2 -adrenergic agonist (clonidine or lofexidine). Other comparisons (placebo, tapered doses of methadone, buprenorphine) made by included studies were too diverse for any meaningful analysis. This review therefore focuses on the nine studies comparing an opioid antagonist (naltrexone or naloxone) plus clonidine or lofexidine versus treatment primarily based on clonidine or lofexidine.Five studies took place in an inpatient setting, two studies were in outpatients with day care, two used day care only for the first day of opioid antagonist administration, and one study described the setting as outpatient

  7. A marine bacterium, Micrococcus MCCB 104, antagonistic to vibrios in prawn larval rearing systems.

    Jayaprakash, N S; Pai, S Somnath; Anas, A; Preetha, R; Philip, Rosamma; Singh, I S Bright

    2005-12-30

    A marine bacterium, Micrococcus MCCB 104, isolated from hatchery water, demonstrated extracellular antagonistic properties against Vibrio alginolyticus, V. parahaemolyticus, V. vulnificus, V. fluviallis, V. nereis, V. proteolyticus, V. mediterranei, V cholerae and Aeromonas sp., bacteria associated with Macrobrachium rosenbergii larval rearing systems. The isolate inhibited the growth of V. alginolyticus during co-culture. The antagonistic component of the extracellular product was heat-stable and insensitive to proteases, lipase, catalase and alpha-amylase. Micrococcus MCCB 104 was demonstrated to be non-pathogenic to M. rosenbergii larvae.

  8. Olfactory Bulb [alpha][subscript 2]-Adrenoceptor Activation Promotes Rat Pup Odor-Preference Learning via a cAMP-Independent Mechanism

    Shakhawat, Amin MD.; Harley, Carolyn W.; Yuan, Qi

    2012-01-01

    In this study, three lines of evidence suggest a role for [alpha][subscript 2]-adrenoreceptors in rat pup odor-preference learning: olfactory bulb infusions of the [alpha][subscript 2]-antagonist, yohimbine, prevents learning; the [alpha][subscript 2]-agonist, clonidine, paired with odor, induces learning; and subthreshold clonidine paired with…

  9. Muscarinic Receptor Agonists and Antagonists

    David R. Kelly

    2001-02-01

    Full Text Available A comprehensive review of pharmacological and medical aspects of the muscarinic class of acetylcholine agonists and antagonists is presented. The therapeutic benefits of achieving receptor subtype selectivity are outlined and applications in the treatment of Alzheimer’s disease are discussed. A selection of chemical routes are described, which illustrate contemporary methodology for the synthesis of chiral medicinal compounds (asymmetric synthesis, chiral pool, enzymes. Routes to bicyclic intrannular amines and intramolecular Diels-Alder reactions are highlighted.

  10. GABAA receptor partial agonists and antagonists

    Krall, Jacob; Balle, Thomas; Krogsgaard-Larsen, Niels

    2015-01-01

    to the local temporal pattern of GABA impact, enabling phasic or tonic inhibition. Specific GABAAR antagonists are essential tools for physiological and pharmacological elucidation of the different type of GABAAR inhibition. However, distinct selectivity among the receptor subtypes (populations) has been shown...... antagonists have been essential in defining the tonic current but both remaining issues concerning the GABAARs involved and the therapeutic possibilities of modulating tonic inhibition underline the need for GABAAR antagonists with improved selectivity....

  11. Pharmacological effects of saw palmetto extract in the lower urinary tract.

    Suzuki, Mayumi; Ito, Yoshihiko; Fujino, Tomomi; Abe, Masayuki; Umegaki, Keizo; Onoue, Satomi; Noguchi, Hiroshi; Yamada, Shizuo

    2009-03-01

    Saw palmetto extract (SPE), an extract from the ripe berries of the American dwarf palm, has been widely used as a therapeutic remedy for urinary dysfunction due to benign prostatic hyperplasia (BPH) in Europe. Numerous mechanisms of action have been proposed for SPE, including the inhibition of 5alpha-reductase. Today, alpha(1)-adrenoceptor antagonists and muscarinic cholinoceptor antagonists are commonly used in the treatment of men with voiding symptoms secondary to BPH. The improvement of voiding symptoms in patients taking SPE may arise from its binding to pharmacologically relevant receptors in the lower urinary tract, such as alpha(1)-adrenoceptors, muscarinic cholinoceptors, 1,4-dihyropyridine receptors and vanilloid receptors. Furthermore, oral administration of SPE has been shown to attenuate the up-regulation of alpha(1)-adrenoceptors in the rat prostate induced by testosterone. Thus, SPE at clinically relevant doses may exert a direct effect on the pharmacological receptors in the lower urinary tract, thereby improving urinary dysfunction in patients with BPH and an overactive bladder. SPE does not have interactions with co-administered drugs or serious adverse events in blood biochemical parameters, suggestive of its relative safety, even with long-term intake. Clinical trials (placebo-controlled and active-controlled trials) of SPE conducted in men with BPH were also reviewed. This review should contribute to the understanding of the pharmacological effects of SPE in the treatment of patients with BPH and associated lower urinary tract symptoms (LUTS).

  12. CGRP receptors mediating CGRP-, adrenomedullin- and amylin-induced relaxation in porcine coronary arteries. Characterization with 'Compound 1' (WO98/11128), a non-peptide antagonist

    Hasbak, P; Sams, A; Schifter, S

    2001-01-01

    . The partial porcine mRNA sequences shared 82 - 92% nucleotide identity with human sequences. 3. The human peptides alphaCGRP, betaCGRP, AM and amylin induced relaxation with pEC(50) values of 8.1, 8.1, 6.7 and 6.1 M respectively. 4. The antagonistic properties of a novel non-peptide CGRP antagonist 'Compound...... 1' (WO98/11128), betaCGRP(8 - 37) and the proposed AM receptor antagonist AM(22 - 52) were compared to the well-known CGRP(1) receptor antagonist alphaCGRP(8 - 37). 5. The alphaCGRP(8 - 37) and betaCGRP(8 - 37) induced concentration-dependent (10(-7) - 10(-5) M) rightward shift of both the alpha......(-6) M) had no significant antagonistic effect. 7. In conclusion, the building blocks forming CGRP and AM receptors were present in the porcine LAD, whereas those of the amylin receptor were not. alphaCGRP, betaCGRP, AM and amylin mediated vasorelaxation via the CGRP receptors. No functional response...

  13. Interleukin-1 antagonists for diabetes

    Mandrup-Poulsen, Thomas

    2013-01-01

    pathways. The testing of specific anti-inflammatory biologics targeting single pro-inflammatory cytokines has provided clinical proof-of-concept. EXPERT OPINION: IL-1 antagonists have so far failed to meet primary end points in recent-onset type 1 diabetes in Phase IIa, and promising Phase I and IIa trials......INTRODUCTION: Diabetes is a currently incurable, epidemically growing global health concern. Contemporary symptomatic treatment targets acute and chronic metabolic consequences of relative or absolute insulin deficiency. Intensive multifactorial therapy is required to attenuate morbidity...... and mortality from late micro- and macrovascular complications, and despite current best clinical practice diabetes is still associated with shortened lifespan. There is an unmet need for interventions targeting pathogenetic mechanisms in diabetes, and the market for such therapies is huge. AREAS COVERED...

  14. The effects of corticotrophin-releasing factor and two antagonists on breathing movements in fetal sheep.

    Bennet, L; Johnston, B M; Vale, W W; Gluckman, P D

    1990-01-01

    1. The respiratory effects of corticotrophin-releasing factor (CRF) and the CRF antagonists alpha-helical CRF 9-41 (alpha hCRF) and [DPhe 12, Nle 21-38] rCRF (12-41) (DPhe CRF) have been studied in unanaesthetized fetal lambs of 125-140 days gestation. 2. CRF when given as a 10 micrograms bolus followed by a 5 micrograms h-1 infusion into a lateral cerebral ventricle caused prolonged continuous fetal breathing movements which were stimulated in both amplitude and frequency but which did not persist during hypoxia. 3. Lower doses of CRF (20 ng bolus followed by 10 ng h-1) increased the amplitude but not the frequency of fetal breathing movements which did not become continuous. 4. At higher doses (20 micrograms bolus followed by 10-15 micrograms h-1) CRF induced cerebral convulsions which were also associated with fetal breathing movements of increased amplitude and frequency. 5. The CRF antagonists alpha hCRF and DPhe CRF both inhibited fetal breathing movements and induced a prolonged apnoea which was resistant to the stimulatory effects of 5-6% hypercapnia. 6. We conclude that CRF stimulates breathing movements in the fetal lamb. The finding that administration of the CRF antagonists alone cause apnoea suggests that CRF may have a tonic role in the regulation of fetal breathing movements. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 PMID:2348387

  15. Drugs interacting with alpha adrenoceptors

    van Zwieten, P. A.

    1989-01-01

    Alpha adrenoceptors should be divided into various subtypes, comprising pre/postsynaptic and alpha 1/alpha 2-subpopulations, respectively. This classification implicates important functional differences between the various alpha-receptor subtypes, including certain differences in signal transduction

  16. Screening alpha-glucosidase and alpha-amylase inhibitors from natural compounds by molecular docking in silico.

    Jhong, Chien-Hung; Riyaphan, Jirawat; Lin, Shih-Hung; Chia, Yi-Chen; Weng, Ching-Feng

    2015-01-01

    The alpha-glucosidase inhibitor is a common oral anti-diabetic drug used for controlling carbohydrates normally converted into simple sugars and absorbed by the intestines. However, some adverse clinical effects have been observed. The present study seeks an alternative drug that can regulate the hyperglycemia by down-regulating alpha-glucosidase and alpha-amylase activity by molecular docking approach to screen the hyperglycemia antagonist against alpha-glucosidase and alpha-amylase activities from the 47 natural compounds. The docking data showed that Curcumin, 16-hydroxy-cleroda-3,13-dine-16,15-olide (16-H), Docosanol, Tetracosanol, Antroquinonol, Berberine, Catechin, Quercetin, Actinodaphnine, and Rutin from 47 natural compounds had binding ability towards alpha-amylase and alpha-glucosidase as well. Curcumin had a better biding ability of alpha-amylase than the other natural compounds. Analyzed alpha-glucosidase activity reveals natural compound inhibitors (below 0.5 mM) are Curcumin, Actinodaphnine, 16-H, Quercetin, Berberine, and Catechin when compared to the commercial drug Acarbose (3 mM). A natural compound with alpha-amylase inhibitors (below 0.5 mM) includes Curcumin, Berberine, Docosanol, 16-H, Actinodaphnine/Tetracosanol, Catechin, and Quercetin when compared to Acarbose (1 mM). When taken together, the implication is that molecular docking is a fast and effective way to screen alpha-glucosidase and alpha-amylase inhibitors as lead compounds of natural sources isolated from medicinal plants. © 2015 International Union of Biochemistry and Molecular Biology.

  17. Carbobenzoxy amino acids: Structural requirements for cholecystokinin receptor antagonist activity

    Maton, P.N.; Sutliff, V.E.; Jensen, R.T.; Gardner, J.D.

    1985-01-01

    The authors used dispersed acini prepared from guinea pig pancreas to examine 28 carbobenzoxy (CBZ) amino acids for their abilities to function as cholecystokinin receptor antagonists. All amino acid derivatives tested, except for CBZ-alanine, CBZ-glycine, and N alpha-CBZ- lysine, were able to inhibit the stimulation of amylase secretion caused by the C-terminal octapeptide of cholecystokinin. In general, there was a good correlation between the ability of a carbobenzoxy amino acid to inhibit stimulated amylase secretion and the ability of the amino acid derivative to inhibit binding of 125 I-cholecystokinin. The inhibition of cholecystokinin-stimulated amylase secretion was competitive, fully reversible, and specific for those secretagogues that interact with the cholecystokinin receptor. The potencies with which the various carbobenzoxy amino acids inhibited the action of cholecystokinin varied 100-fold and CBZ-cystine was the most potent cholecystokinin receptor antagonist. This variation in potency was primarily but not exclusively a function of the hydrophobicity of the amino acid side chain

  18. Combination cancer chemotherapy with one compound: pluripotent bradykinin antagonists.

    Stewart, John M; Gera, Lajos; Chan, Daniel C; York, Eunice J; Simkeviciene, Vitalija; Bunn, Paul A; Taraseviciene-Stewart, Laimute

    2005-08-01

    Lung and prostate cancers are major health problems worldwide. Treatments with standard chemotherapy agents are relatively ineffective. Combination chemotherapy gives better treatment than a single agent because the drugs can inhibit the cancer in different pathways, but new therapeutic agents are needed for the treatment of both tumor types. Bradykinin (BK) antagonists offer advantages of combination therapy in one compound. These promising multitargeted anti-cancer compounds selectively stimulate apoptosis in cancers and also inhibit both angiogenesis and matrix metalloprotease (MMP) action in treated lung and prostate tumors in nude mice. The highly potent, metabolism-resistant bradykinin antagonist peptide dimer, B-9870 [SUIM-(DArg-Arg-Pro-Hyp-Gly-Igl-Ser-DIgl-Oic-Arg)2] (SUIM=suberimidyl; Hyp=4-hydroxyproline; Igl=alpha-(2-indanyl)glycine; Oic=octahydroindole-2-carboxylic acid) and its non-peptide mimetic, BKM-570 [2,3,4,5,6-pentafluorocinnamoyl-(o-2,6-dichlorobenzyl)-L-tyrosine-N-(4-amino-2,2,6,6-tetramethylpiperidyl)amide] are superior to the widely used but toxic chemotherapeutic drugs cisplatin and taxotere. In certain combinations, they act synergistically with standard anti-cancer drugs. Due to its structure and biological activity, BKM-570 is an attractive lead compound for derivatization and evaluation for lung and prostate cancer drugs.

  19. The determination of $\\alpha_s$ by the ALPHA collaboration

    Bruno, Mattia

    2016-01-01

    We review the ALPHA collaboration strategy for obtaining the QCD coupling at high scale. In the three-flavor effective theory it avoids the use of perturbation theory at $\\alpha > 0.2$ and at the same time has the physical scales small compared to the cutoff $1/a$ in all stages of the computation. The result $\\Lambda_\\overline{MS}^{(3)}=332(14)$~MeV is translated to $\\alpha_\\overline{MS}(m_Z)=0.1179(10)(2)$ by use of (high order) perturbative relations between the effective theory couplings at the charm and beauty quark "thresholds". The error of this perturbative step is discussed and estimated as $0.0002$.

  20. Alpha-adrenergic receptors in rat skeletal muscle

    Rattigan, S; Appleby, G J; Edwards, S J

    1986-01-01

    Sarcolemma-enriched preparations from muscles rich in slow oxidative red fibres contained specific binding sites for the alpha 1 antagonist, prazosin (e.g. soleus Kd 0.13 nM, Bmax 29 fmol/mg protein). Binding sites for prazosin were almost absent from white muscle. Displacement of prazosin bindin...... adrenergic receptors are present on the sarcolemma of slow oxidative red fibres of rat skeletal muscle. The presence provides the mechanistic basis for apparent alpha-adrenergic effects to increase glucose and oxygen uptake in perfused rat hindquarter....

  1. From Chemotherapy-Induced Emesis to Neuroprotection: Therapeutic Opportunities for 5-HT3 Receptor Antagonists.

    Fakhfouri, Gohar; Mousavizadeh, Kazem; Mehr, Sharam Ejtemaei; Dehpour, Ahmad Reza; Zirak, Mohammad Reza; Ghia, Jean-Eric; Rahimian, Reza

    2015-12-01

    5-HT3 receptor antagonists are extensively used as efficacious agents in counteracting chemotherapy-induced emesis. Recent investigations have shed light on other potential effects (analgesic, anxiolytic, and anti-psychotic). Some studies have reported neuroprotective properties for the 5-HT3 receptor antagonists in vitro and in vivo. When administered to Aβ-challenged rat cortical neurons, 5-HT3 receptor antagonists substantially abated apoptosis, elevation of cytosolic Ca(2), glutamate release, reactive oxygen species (ROS) generation, and caspase-3 activity. In addition, in vivo studies show that 5-HT3 receptor antagonists possess, alongside their anti-emetic effects, notable immunomodulatory properties in CNS. We found that pretreatment with tropisetron significantly improved neurological deficits and diminished leukocyte transmigration into the brain, TNF-α level, and brain infarction in a murine model of embolic stroke. Our recent investigation revealed that tropisetron protects against Aβ-induced neurotoxicity in vivo through both 5-HT3 receptor-dependent and -independent pathways. Tropisetron, in vitro, was found to be an efficacious inhibitor of the signaling pathway leading to the activation of pro-inflammatory NF-κB, a transcription factor pivotal to the upregulation of several neuroinflammatory mediators in brain. This mini review summarizes novel evidence concerning effects of 5-HT3 antagonists and their possible mechanisms of action in ameliorating neurodegenerative diseases including Alzheimer, multiple sclerosis, and stroke. Further, we discuss some newly synthesized 5-HT3 receptor antagonists with dual properties of 5-HT3 receptor blockade/alpha-7 nicotinic receptor activator and their potential in management of memory impairment. Since 5-HT3 receptor antagonists possess a large therapeutic window, they can constitute a scaffold for design and synthesis of new neuroprotective medications.

  2. Quantitation of alpha 1-adrenergic receptors in porcine uterine and mesenteric arteries

    Farley, D.B.; Ford, S.P.; Reynolds, L.P.; Bhatnagar, R.K.; Van Orden, D.E.

    1984-01-01

    The activation of vascular alpha-adrenergic receptors may be involved in the control of uterine blood flow. A radioligand binding assay with the use of the alpha 1-adrenergic antagonist 3 H-WB-4101 was established to characterize the alpha-adrenergic receptors in uterine and mesenteric arterial membranes obtained from nonpregnant pigs. Specific binding of 3 H-WB-4101 was rapid, saturable, and exhibited the alpha-adrenergic agonist potency order of (-)-epinephrine inhibition constant [Ki] . 0.6 mumol/L greater than (-)-norepinephrine (Ki . 1.5 mumol/L) much greater than (-)-isoproterenol (Ki . 120 mumol/L). The alpha-adrenergic antagonist phentolamine (Ki . 6.0 nmol/L) was 200 times more potent than the beta-adrenergic antagonist (+/-)-propranolol (Ki . 1,200 nmol/L); the alpha 1-selective antagonist prazosin (Ki . 1.2 nmol/L) was 130 times more potent than the alpha 2-selective antagonist yohimbine (Ki . 160 nmol/L). Scatchard analysis, as well as iterative curve-fitting analysis, demonstrated that 3 H-WB-4101 binding by arterial membranes was to a single class of binding sites. Uterine arteries exhibited greater maximal binding capacity (BMax) than that of mesenteric arteries (47.5 +/- 3.2 versus 30.9 +/- 3.6 fmol per milligram of protein, p less than 0.01), but the uterine artery dissociation constant (Kd) was higher, thus indicating a lower affinity, when compared with mesenteric artery (0.43 +/- 0.04 versus 0.33 +/- 0.04 nmol/L, p less than 0.05)

  3. Antagonistic Phenomena in Network Dynamics

    Motter, Adilson E.; Timme, Marc

    2018-03-01

    Recent research on the network modeling of complex systems has led to a convenient representation of numerous natural, social, and engineered systems that are now recognized as networks of interacting parts. Such systems can exhibit a wealth of phenomena that not only cannot be anticipated from merely examining their parts, as per the textbook definition of complexity, but also challenge intuition even when considered in the context of what is now known in network science. Here, we review the recent literature on two major classes of such phenomena that have far-reaching implications: (a) antagonistic responses to changes of states or parameters and (b) coexistence of seemingly incongruous behaviors or properties - both deriving from the collective and inherently decentralized nature of the dynamics. They include effects as diverse as negative compressibility in engineered materials, rescue interactions in biological networks, negative resistance in fluid networks, and the Braess paradox occurring across transport and supply networks. They also include remote synchronization, chimera states, and the converse of symmetry breaking in brain, power-grid, and oscillator networks as well as remote control in biological and bioinspired systems. By offering a unified view of these various scenarios, we suggest that they are representative of a yet broader class of unprecedented network phenomena that ought to be revealed and explained by future research.

  4. Lyman Alpha Control

    Nielsen, Daniel Stefaniak

    2015-01-01

    This document gives an overview of how to operate the Lyman Alpha Control application written in LabVIEW along with things to watch out for. Overview of the LabVIEW code itself as well as the physical wiring of and connections from/to the NI PCI-6229 DAQ box is also included. The Lyman Alpha Control application is the interface between the ALPHA sequencer and the HighFinesse Wavelength Meter as well as the Lyman Alpha laser setup. The application measures the wavelength of the output light from the Lyman Alpha cavity through the Wavelength Meter. The application can use the Wavelength Meter’s PID capabilities to stabilize the Lyman Alpha laser output as well as switch between up to three frequencies.

  5. New ALPHA-2 magnet

    Anaïs Schaeffer

    2012-01-01

    On 21 June, members of the ALPHA collaboration celebrated the handover of the first solenoid designed for the ALPHA-2 experiment. The magnet has since been successfully installed and is working well.   Khalid Mansoor, Sumera Yamin and Jeffrey Hangst in front of the new ALPHA-2 solenoid. “This was the first of three identical solenoids that will be installed between now and September, as the rest of the ALPHA-2 device is installed and commissioned,” explains ALPHA spokesperson Jeffrey Hangst. “These magnets are designed to allow us to transfer particles - antiprotons, electrons and positrons - between various parts of the new ALPHA-2 device by controlling the transverse size of the particle bunch that is being transferred.” Sumera Yamin and Khalid Mansoor, two Pakistani scientists from the National Centre for Physics in Islamabad, came to CERN in February specifically to design and manufacture these magnets. “We had the chance to work on act...

  6. Simultaneous evaluation of the pre- and postsynaptic interactions of alpha-2 adrenergic agents in the phenoxybenzamine-treated dog saphenous vein

    Buckner, S.; Morse, P.; DeBernardis, J.; Kyncyl, J.

    1986-01-01

    Functional alpha-2 adrenergic receptors can be demonstrated on both the neuronal and muscular sides of the sympathetic synapse in the superfused, electrically stimulated, 3 H-NE-loaded dog saphenous vein (DSV). Selective alkylation of the alpha-1 subtype in this tissue by phenoxybenzamine produced a preparation which contained functional alpha adrenergic receptors of only the alpha-2 subtype at both locations and provided an experimental model suitable for differentiating alpha-2 selective compounds according to their pre- vs postsynaptic preference. A number of standard alpha-2 selective agonists and antagonists were tested in this model. None of these agents exhibited any significant degree of presynaptic or postsynaptic selectivity

  7. Structural determinants for antagonist pharmacology that distinguish the rho1 GABAC receptor from GABAA receptors.

    Zhang, Jianliang; Xue, Fenqin; Chang, Yongchang

    2008-10-01

    GABA receptor (GABAR) types C (GABACR) and A (GABAAR) are both GABA-gated chloride channels that are distinguished by their distinct competitive antagonist properties. The structural mechanism underlying these distinct properties is not well understood. In this study, using previously identified binding residues as a guide, we made individual or combined mutations of nine binding residues in the rho1 GABACR subunit to their counterparts in the alpha1beta2gamma2 GABAAR or reverse mutations in alpha1 or beta2 subunits. The mutants were expressed in Xenopus laevis oocytes and tested for sensitivities of GABA-induced currents to the GABAA and GABAC receptor antagonists. The results revealed that bicuculline insensitivity of the rho1 GABACR was mainly determined by Tyr106, Phe138 and Phe240 residues. Gabazine insensitivity of the rho1 GABACR was highly dependent on Tyr102, Tyr106, and Phe138. The sensitivity of the rho1 GABACR to 3-aminopropyl-phosphonic acid and its analog 3-aminopropyl-(methyl)phosphinic acid mainly depended on residues Tyr102, Val140, FYS240-242, and Phe138. Thus, the residues Tyr102, Tyr106, Phe138, and Phe240 in the rho1 GABACR are major determinants for its antagonist properties distinct from those in the GABAAR. In addition, Val140 in the GABACR contributes to 3-APA binding. In conclusion, we have identified the key structural elements underlying distinct antagonist properties for the GABACR. The mechanistic insights were further extended and discussed in the context of antagonists docking to the homology models of GABAA or GABAC receptors.

  8. Blood flow distribution with adrenergic and histaminergic antagonists

    Baker, C.H.; Davis, D.L.; Sutton, E.T.

    1989-03-01

    Superficial fibular nerve stimulation (SFNS) causes increased pre- and post-capillary resistances as well as increased capillary permeability in the dog hind paw. These responses indicate possible adrenergic and histaminergic interactions. The distribution of blood flow between capillaries and arteriovenous anastomoses (AVA) may depend on the relative effects of these neural inputs. Right hind paws of anesthetized heparinized dogs were vascularly and neurally isolated and perfused with controlled pressure. Blood flow distribution was calculated from the venous recovery of 85Sr-labeled microspheres (15 microns). The mean transit times of 131I-albumin and 85Sr-labeled microspheres were calculated. The effects of adrenergic and histaminergic antagonists with and without SFNS were determined. Phentolamine blocked the entire response to SFNS. Prazosin attenuated increases in total and AVA resistance. Yohimbine prevented increased total resistance, attenuated the AVA resistance increase, and revealed a decrease in capillary circuit resistance. Pyrilamine attenuated total resistance increase while SFNS increased capillary and AVA resistances. Metiamide had no effect on blood flow distribution with SFNS. The increase in AVA resistance with SFNS apparently resulted from a combination of alpha 1 and alpha 2 receptor stimulation but not histaminergic effects.

  9. Blood flow distribution with adrenergic and histaminergic antagonists

    Baker, C.H.; Davis, D.L.; Sutton, E.T.

    1989-01-01

    Superficial fibular nerve stimulation (SFNS) causes increased pre- and post-capillary resistances as well as increased capillary permeability in the dog hind paw. These responses indicate possible adrenergic and histaminergic interactions. The distribution of blood flow between capillaries and arteriovenous anastomoses (AVA) may depend on the relative effects of these neural inputs. Right hind paws of anesthetized heparinized dogs were vascularly and neurally isolated and perfused with controlled pressure. Blood flow distribution was calculated from the venous recovery of 85Sr-labeled microspheres (15 microns). The mean transit times of 131I-albumin and 85Sr-labeled microspheres were calculated. The effects of adrenergic and histaminergic antagonists with and without SFNS were determined. Phentolamine blocked the entire response to SFNS. Prazosin attenuated increases in total and AVA resistance. Yohimbine prevented increased total resistance, attenuated the AVA resistance increase, and revealed a decrease in capillary circuit resistance. Pyrilamine attenuated total resistance increase while SFNS increased capillary and AVA resistances. Metiamide had no effect on blood flow distribution with SFNS. The increase in AVA resistance with SFNS apparently resulted from a combination of alpha 1 and alpha 2 receptor stimulation but not histaminergic effects

  10. Alpha Shapes and Proteins

    Winter, Pawel; Sterner, Henrik; Sterner, Peter

    2009-01-01

    We provide a unified description of (weighted) alpha shapes, beta shapes and the corresponding simplicialcomplexes. We discuss their applicability to various protein-related problems. We also discuss filtrations of alpha shapes and touch upon related persistence issues.We claim that the full...... potential of alpha-shapes and related geometrical constructs in protein-related problems yet remains to be realized and verified. We suggest parallel algorithms for (weighted) alpha shapes, and we argue that future use of filtrations and kinetic variants for larger proteins will need such implementation....

  11. Calcium antagonists for aneurysmal subarachnoid haemorrhage

    Dorhout Mees, S. M.; Rinkel, G. J. E.; Feigin, V. L.; Algra, A.; van den Bergh, W. M.; Vermeulen, M.; van Gijn, J.

    2007-01-01

    BACKGROUND: Secondary ischaemia is a frequent cause of poor outcome in patients with subarachnoid haemorrhage (SAH). Its pathogenesis has been incompletely elucidated, but vasospasm probably is a contributing factor. Experimental studies have suggested that calcium antagonists can prevent or reverse

  12. Benzodiazepine receptor antagonists for hepatic encephalopathy

    Als-Nielsen, B; Gluud, L L; Gluud, C

    2004-01-01

    Hepatic encephalopathy may be associated with accumulation of substances that bind to a receptor-complex in the brain resulting in neural inhibition. Benzodiazepine receptor antagonists may have a beneficial effect on patients with hepatic encephalopathy.......Hepatic encephalopathy may be associated with accumulation of substances that bind to a receptor-complex in the brain resulting in neural inhibition. Benzodiazepine receptor antagonists may have a beneficial effect on patients with hepatic encephalopathy....

  13. Targeted Alpha Therapy: From Alpha to Omega

    Allen, Barry J; Clarke, Raymond; Huang Chenyu

    2013-01-01

    This review covers the broad spectrum of Targeted Alpha Therapy (TAT) research in Australia; from in vitro and in vivo studies to clinical trials. The principle of tumour anti-vascular alpha therapy (TAVAT) is discussed in terms of its validation by Monte Carlo calculations of vascular models and the potential role of biological dosimetry is examined. Summmary of this review is as follows: 1. The essence of TAT 2. Therapeutic objectives 3. TAVAT and Monte Carlo microdosimetry 4. Biological dosimetry 5. Preclinical studies 6. Clinical trials 7. What next? 8. Obstacles. (author)

  14. Alpha1-antitrypsin deficiency

    Stolk, Jan; Seersholm, Niels; Kalsheker, Noor

    2006-01-01

    The Alpha One International Registry (AIR), a multinational research program focused on alpha1-antitrypsin (AAT) deficiency, was formed in response to a World Health Organization recommendation. Each of the nearly 20 participating countries maintains a national registry of patients with AAT defic...

  15. Alpha Thalassemia (For Parents)

    ... Safe Videos for Educators Search English Español Alpha Thalassemia KidsHealth / For Parents / Alpha Thalassemia What's in this ... Symptoms Diagnosis Treatment Print en español Alfa talasemia Thalassemias Thalassemias are a group of blood disorders that ...

  16. Buffett’s Alpha

    Frazzini, Andrea; Kabiller, David; Heje Pedersen, Lasse

    Berkshire Hathaway has realized a Sharpe ratio of 0.76, higher than any other stock or mutual fund with a history of more than 30 years, and Berkshire has a significant alpha to traditional risk factors. However, we find that the alpha becomes insignificant when controlling for exposures to Betting...

  17. Alpha clustering in nuclei

    Hodgson, P.E.

    1990-01-01

    The effects of nucleon clustering in nuclei are described, with reference to both nuclear structure and nuclear reactions, and the advantages of using the cluster formalism to describe a range of phenomena are discussed. It is shown that bound and scattering alpha-particle states can be described in a unified way using an energy-dependent alpha-nucleus potential. (author)

  18. Alpha 2-adrenergic receptor turnover in adipose tissue and kidney: irreversible blockade of alpha 2-adrenergic receptors by benextramine

    Taouis, M.; Berlan, M.; Lafontan, M.

    1987-01-01

    The recovery of post- and extrasynaptic alpha 2-adrenergic receptor-binding sites was studied in vivo in male golden hamsters after treatment with an irreversible alpha-adrenoceptor antagonist benextramine, a tetramine disulfide that possesses a high affinity for alpha 2-binding sites. The kidney alpha 2-adrenergic receptor number was measured with [ 3 H]yohimbine, whereas [ 3 H]clonidine was used for fat cell and brain membrane alpha 2-binding site identification. Benextramine treatment of fat cell, kidney, and brain membranes reduced or completely suppressed, in an irreversible manner, [ 3 H] clonidine and [ 3 H]yohimbine binding without modifying adenosine (A1-receptor) and beta-adrenergic receptor sites. This irreversible binding was also found 1 and 2 hr after intraperitoneal administration of benextramine to the hamsters. Although it bound irreversibly to peripheral and central alpha 2-adrenergic receptors on isolated membranes, benextramine was unable to cross the blood-brain barrier of the hamster at the concentrations used (10-20 mg/kg). After the irreversible blockade, alpha 2-binding sites reappeared in kidney and adipose tissue following a monoexponential time course. Recovery of binding sites was more rapid in kidney than in adipose tissue; the half-lives of the receptor were 31 and 46 hr, respectively in the tissues. The rates of receptor production were 1.5 and 1.8 fmol/mg of protein/hr in kidney and adipose tissue. Reappearance of alpha 2-binding sites was associated with a rapid recovery of function (antilipolytic potencies of alpha 2-agonists) in fat cells inasmuch as occupancy of 15% of [ 3 H]clonidine-binding sites was sufficient to promote 40% inhibition of lipolysis. Benextramine is a useful tool to estimate turnover of alpha 2-adrenergic receptors under normal and pathological situations

  19. Genetics Home Reference: alpha thalassemia

    ... Facebook Twitter Home Health Conditions Alpha thalassemia Alpha thalassemia Printable PDF Open All Close All Enable Javascript to view the expand/collapse boxes. Description Alpha thalassemia is a blood disorder that reduces the production ...

  20. NMDA receptor antagonists inhibit catalepsy induced by either dopamine D1 or D2 receptor antagonists.

    Moore, N A; Blackman, A; Awere, S; Leander, J D

    1993-06-11

    In the present study, we investigated the ability of NMDA receptor antagonists to inhibit catalepsy induced by haloperidol, or SCH23390 and clebopride, selective dopamine D1 and D2 receptor antagonists respectively. Catalepsy was measured by recording the time the animal remained with its forepaws placed over a rod 6 cm above the bench. Pretreatment with either the non-competitive NMDA receptor antagonist, MK-801 (0.25-0.5 mg/kg i.p.) or the competitive antagonist, LY274614 (10-20 mg/kg i.p.) reduced the cataleptic response produced by haloperidol (10 mg/kg), SCH23390 (2.5-10 mg/kp i.p.) or clebopride (5-20 mg/kg i.p.). This demonstrates that NMDA receptor antagonists will reduce both dopamine D1 and D2 receptor antagonist-induced catalepsy. Muscle relaxant doses of chlordiazepoxide (10 mg/kg i.p.) failed to reduce the catalepsy induced by haloperidol, suggesting that the anticataleptic effect of the NMDA receptor antagonists was not due to a non-specific action. These results support the hypothesis that NMDA receptor antagonists may have beneficial effects in disorders involving reduced dopaminergic function, such as Parkinson's disease.

  1. The alpha channeling effect

    Fisch, N. J.

    2015-12-01

    Alpha particles born through fusion reactions in a tokamak reactor tend to slow down on electrons, but that could take up to hundreds of milliseconds. Before that happens, the energy in these alpha particles can destabilize on collisionless timescales toroidal Alfven modes and other waves, in a way deleterious to energy confinement. However, it has been speculated that this energy might be instead be channeled into useful energy, so as to heat fuel ions or to drive current. Such a channeling needs to be catalyzed by waves Waves can produce diffusion in energy of the alpha particles in a way that is strictly coupled to diffusion in space. If these diffusion paths in energy-position space point from high energy in the center to low energy on the periphery, then alpha particles will be cooled while forced to the periphery. The energy from the alpha particles is absorbed by the wave. The amplified wave can then heat ions or drive current. This process or paradigm for extracting alpha particle energy collisionlessly has been called alpha channeling. While the effect is speculative, the upside potential for economical fusion is immense. The paradigm also operates more generally in other contexts of magnetically confined plasma.

  2. Postcountershock myocardial damage after pretreatment with adrenergic and calcium channel antagonists in halothane-anesthetized dogs

    Gaba, D.M.; Metz, S.; Maze, M.

    1985-05-01

    Transthoracic electric countershock can cause necrotic myocardial lesions in humans as well as experimental animals. The authors investigated the effect on postcountershock myocardial damage of pretreatment with prazosin, an alpha-1 antagonist; L-metoprolol, a beta-1 antagonist, and verapamil, a calcium channel-blocking agent. Twenty dogs were anesthetized with halothane and given two transthoracic countershocks of 295 delivered joules each after drug or vehicle treatment. Myocardial injury was quantitated 24 h following countershock by measuring the uptake of technetium-99m pyrophosphate in the myocardium. Elevated technetium-99m pyrophosphate uptake occurred in visible lesions in most dogs regardless of drug treatment. For each of four parameters of myocardial damage there was no statistically significant difference between control animals and those treated with prazosin, metoprolol, or verapamil. These data suggest that adrenergic or calcium channel-mediated mechanisms are not involved in the pathogenesis of postcountershock myocardial damage.

  3. Chloroquine, quinine, procaine, quinidine and clomipramine are prostaglandin agonists and antagonists.

    Manku, M S; Horrobin, D F

    1976-11-01

    Chloroquine, quinine, procaine, quinidine and clomipramine behave as prostaglandin (PG) antagonists in a rat mesenteric vascular bed preparation. The ID50 concentrations were within the range of therapeutically effective human plasma levels in each case. Antagonism to PGE2 was studied in detail and seemed to be at least in part competitive. The drugs also antagonized the effects of PGs A1, A2, F2alpha and E1. Each drug also had weak prostaglandin agonist activity but only over a very narrow range of concentrations. It is possible that some of the clinical actions of these drugs may depend on blockade or imitation of natural PG effects. The findings suggest new approaches to the search for PG antagonists, a new screening technique for anti-inflammatory drugs and possible new uses for these established drugs. A preliminary study suggests that chloroquine may be successful in closing a patent ductus arteriosus in infants.

  4. Alpha7 nicotinic receptor mediated protection against ethanol-induced cytotoxicity in PC12 cells.

    Li, Y; King, M A; Grimes, J; Smith, N; de Fiebre, C M; Meyer, E M

    1999-01-16

    Ethanol caused a concentration-dependent loss of PC12 cells over a 24 h interval, accompanied by an increase in intracellular calcium. The specific alpha7 nicotinic receptor partial agonist DMXB attenuated both of these ethanol-induced actions at a concentration (3 microM) found previously to protect against apoptotic and necrotic cell loss. The alpha7 nicotinic receptor antagonist methylylaconitine blocked the neuroprotective action of DMXB when applied with but not 30 min after the agonist. These results indicate that activation of alpha7 nicotinic receptors may be therapeutically useful in preventing ethanol-neurotoxicity. Copyright 1999 Elsevier Science B.V.

  5. Alpha Hydroxy Acids

    ... or tenderness (8), chemical burns (6), and increased sunburn (3). The frequency of such reports for skin ... bear a statement that conveys the following information: Sunburn Alert: This product contains an alpha hydroxy acid ( ...

  6. Justify your alpha

    Lakens, Daniel; Adolfi, Federico G.; Albers, Casper J.; Anvari, Farid; Apps, Matthew A.J.; Argamon, Shlomo E.; Baguley, Thom; Becker, Raymond B.; Benning, Stephen D.; Bradford, Daniel E.; Buchanan, Erin M.; Caldwell, Aaron R.; Van Calster, Ben; Carlsson, Rickard; Chen, Sau Chin; Chung, Bryan; Colling, Lincoln J.; Collins, Gary S.; Crook, Zander; Cross, Emily S.; Daniels, Sameera; Danielsson, Henrik; Debruine, Lisa; Dunleavy, Daniel J.; Earp, Brian D.; Feist, Michele I.; Ferrell, Jason D.; Field, James G.; Fox, Nicholas W.; Friesen, Amanda; Gomes, Caio; Gonzalez-Marquez, Monica; Grange, James A.; Grieve, Andrew P.; Guggenberger, Robert; Grist, James; Van Harmelen, Anne Laura; Hasselman, Fred; Hochard, Kevin D.; Hoffarth, Mark R.; Holmes, Nicholas P.; Ingre, Michael; Isager, Peder M.; Isotalus, Hanna K.; Johansson, Christer; Juszczyk, Konrad; Kenny, David A.; Khalil, Ahmed A.; Konat, Barbara; Lao, Junpeng; Larsen, Erik Gahner; Lodder, Gerine M.A.; Lukavský, Jiří; Madan, Christopher R.; Manheim, David; Martin, Stephen R.; Martin, Andrea E.; Mayo, Deborah G.; McCarthy, Randy J.; McConway, Kevin; McFarland, Colin; Nio, Amanda Q.X.; Nilsonne, Gustav; De Oliveira, Cilene Lino; De Xivry, Jean Jacques Orban; Parsons, Sam; Pfuhl, Gerit; Quinn, Kimberly A.; Sakon, John J.; Saribay, S. Adil; Schneider, Iris K.; Selvaraju, Manojkumar; Sjoerds, Zsuzsika; Smith, Samuel G.; Smits, Tim; Spies, Jeffrey R.; Sreekumar, Vishnu; Steltenpohl, Crystal N.; Stenhouse, Neil; Świątkowski, Wojciech; Vadillo, Miguel A.; Van Assen, Marcel A.L.M.; Williams, Matt N.; Williams, Samantha E.; Williams, Donald R.; Yarkoni, Tal; Ziano, Ignazio; Zwaan, Rolf A.

    2018-01-01

    In response to recommendations to redefine statistical significance to P ≤ 0.005, we propose that researchers should transparently report and justify all choices they make when designing a study, including the alpha level.

  7. Antihydrogen detection in ALPHA

    Hydomako, Richard, E-mail: rhydomako@phas.ucalgary.ca [University of Calgary, Department of Physics and Astronomy (Canada); Bruun Andresen, Gorm [Aarhus University, Department of Physics and Astronomy (Denmark); Ashkezari, Mohammad Dehghani [Simon Fraser University, Department of Physics (Canada); Baquero-Ruiz, Marcelo [University of California, Department of Physics (United States); Bertsche, William [Swansea University, Department of Physics (United Kingdom); Butler, Eoin [CERN, European Laboratory for Particle Physics (Switzerland); Bowe, Paul David [Aarhus University, Department of Physics and Astronomy (Denmark); Cesar, Claudo Lenz [Universidade Federal do Rio de Janeiro, Instituto de Fsica (Brazil); Chapman, Steve [University of California, Department of Physics (United States); Charlton, Michael [Swansea University, Department of Physics (United Kingdom); Fajans, Joel [University of California, Department of Physics (United States); Friesen, Tim; Fujiwara, Makoto C. [University of Calgary, Department of Physics and Astronomy (Canada); Gill, David Russell [TRIUMF (Canada); Hangst, Jeffrey Scott [Aarhus University, Department of Physics and Astronomy (Denmark); Hardy, Walter Newbold [University of British Columbia, Department of Physics and Astronomy (Canada); Hayano, Ryugo S. [University of Tokyo, Department of Physics (Japan); Hayden, Michael Edward [Simon Fraser University, Department of Physics (Canada); Humphries, Andrew James [Swansea University, Department of Physics (United Kingdom); Jonsell, Svante [Stockholm University, Fysikum (Sweden); Collaboration: ALPHA Collaboration; and others

    2012-12-15

    The ALPHA project is an international collaboration, based at CERN, with the experimental goal of performing precision spectroscopic measurements on antihydrogen. As part of this endeavor, the ALPHA experiment includes a silicon tracking detector. This detector consists of a three-layer array of silicon modules surrounding the antihydrogen trapping region of the ALPHA apparatus. Using this device, the antihydrogen annihilation position can be determined with a spatial resolution of better than 5 mm. Knowledge of the annihilation distribution was a critical component in the recently successful antihydrogen trapping effort. This paper will describe the methods used to reconstruct annihilation events in the ALPHA detector. Particular attention will be given to the description of the background rejection criteria.

  8. Coaching the alpha male.

    Ludeman, Kate; Erlandson, Eddie

    2004-05-01

    Highly intelligent, confident, and successful, alpha males represent about 70% of all senior executives. Natural leaders, they willingly take on levels of responsibility most rational people would find overwhelming. But many of their quintessential strengths can also make alphas difficult to work with. Their self-confidence can appear domineering. Their high expectations can make them excessively critical. Their unemotional style can keep them from inspiring their teams. That's why alphas need coaching to broaden their interpersonal tool kits while preserving their strengths. Drawing from their experience coaching more than 1,000 senior executives, the authors outline an approach tailored specifically for the alpha. Coaches get the alpha's attention by inundating him with data from 360-degree feedback presented in ways he will find compelling--both hard-boiled metrics and vivid verbatim comments from colleagues about his strengths and weaknesses. A 360-degree assessment is a wake-up call for most alphas, providing undeniable proof that their behavior doesn't work nearly as well as they think it does. That paves the way for a genuine commitment to change. In order to change, the alpha must venture into unfamiliar--and often uncomfortable--psychological territory. He must admit vulnerability, accept accountability not just for his own work for others', connect with his underlying emotions, learn to motivate through a balance of criticism and validation, and become aware of unproductive behavior patterns. The goal of executive coaching is not simply to treat the alpha as an individual problem but to improve the entire team dynamic. Initial success creates an incentive to persevere, and the virtuous cycle reverberates throughout the entire organization.

  9. Effects of three antagonists on selected pharmacodynamic effects of sublingually administered detomidine in the horse.

    Knych, Heather K; Stanley, Scott D

    2014-01-01

    To describe the effects of alpha2 -adrenergic receptor antagonists on the pharmacodynamics of sublingual (SL) detomidine in the horse. Randomized crossover design. Nine healthy adult horses with an average age of 7.6 ± 6.5 years. Four treatment groups were studied: 1) 0.04 mg kg(-1) detomidine SL; 2) 0.04 mg kg(-1) detomidine SL followed 1 hour later by 0.075 mg kg(-1) yohimbine intravenously (IV); 3) 0.04 mg kg(-1) detomidine SL followed 1 hour later by 4 mg kg(-1) tolazoline IV; and 4) 0.04 mg kg(-1) detomidine SL followed 1 hour later by 0.12 mg kg(-1) atipamezole IV. Each horse received all treatments with a minimum of 1 week between treatments. Blood samples were obtained and plasma analyzed for yohimbine, atipamezole and tolazoline concentrations by liquid chromatography-mass spectrometry. Behavioral effects, heart rate and rhythm, glucose, packed cell volume (PCV) and plasma proteins were monitored. Chin-to-ground distance increased following administration of the antagonists, however, this effect was transient, with a return to pre-reversal values as early as 1 hour. Detomidine induced bradycardia and increased incidence of atrioventricular blocks were either transiently or incompletely antagonized by all antagonists. PCV and glucose concentrations increased with tolazoline administration, and atipamezole subjectively increased urination frequency but not volume. At the doses administered in this study, the alpha2 -adrenergic antagonistic effects of tolazoline, yohimbine and atipamezole on cardiac and behavioral effects elicited by SL administration of detomidine are transient and incomplete. © 2013 Association of Veterinary Anaesthetists and the American College of Veterinary Anesthesia and Analgesia.

  10. Alpha - Skew Pi - Armendariz Rings

    Areej M Abduldaim

    2018-03-01

    Full Text Available In this article we introduce a new concept called Alpha-skew Pi-Armendariz rings (Alpha - S Pi - ARas a generalization of the notion of Alpha-skew Armendariz rings.Another important goal behind studying this class of rings is to employ it in order to design a modern algorithm of an identification scheme according to the evolution of using modern algebra in the applications of the field of cryptography.We investigate general properties of this concept and give examples for illustration. Furthermore, this paperstudy the relationship between this concept and some previous notions related to Alpha-skew Armendariz rings. It clearly presents that every weak Alpha-skew Armendariz ring is Alpha-skew Pi-Armendariz (Alpha-S Pi-AR. Also, thisarticle showsthat the concepts of Alpha-skew Armendariz rings and Alpha-skew Pi- Armendariz rings are equivalent in case R is 2-primal and semiprime ring.Moreover, this paper proves for a semicommutative Alpha-compatible ringR that if R[x;Alpha] is nil-Armendariz, thenR is an Alpha-S Pi-AR. In addition, if R is an Alpha - S Pi -AR, 2-primal and semiprime ring, then N(R[x;Alpha]=N(R[x;Alpha]. Finally, we look forwardthat Alpha-skew Pi-Armendariz rings (Alpha-S Pi-ARbe more effect (due to their properties in the field of cryptography than Pi-Armendariz rings, weak Armendariz rings and others.For these properties and characterizations of the introduced concept Alpha-S Pi-AR, we aspire to design a novel algorithm of an identification scheme.

  11. ALPHA-2: the sequel

    Katarina Anthony

    2012-01-01

    While many experiments are methodically planning for intense works over the long shutdown, there is one experiment that is already working at full steam: ALPHA-2. Its final components arrived last month and will completely replace the previous ALPHA set-up. Unlike its predecessor, this next generation experiment has been specifically designed to measure the properties of antimatter.   The ALPHA team lower the new superconducting solenoid magnet into place. The ALPHA collaboration is working at full speed to complete the ALPHA-2 set-up for mid-November – this will give them a few weeks of running before the AD shutdown on 17 December. “We really want to get some experience with this device this year so that, if we need to make any changes, we will have time during the long shutdown in which to make them,” says Jeffrey Hangst, ALPHA spokesperson. “Rather than starting the 2014 run in the commissioning stage, we will be up and running from the get go.&...

  12. Design and synthesis of novel platelet fibrinogen receptor antagonists with 2H-1,4-benzoxazine-3(4H)-one scaffold. A systematic study.

    Anderluh, Marko; Cesar, Jozko; Stefanic, Petra; Kikelj, Danijel; Janes, Damjan; Murn, Jernej; Nadrah, Kristina; Tominc, Mojca; Addicks, Elisabeth; Giannis, Athanassios; Stegnar, Mojca; Dolenc, Marija Sollner

    2005-01-01

    New platelet glycoprotein IIb/IIIa (GP IIb/IIIa, integrin alpha(IIb)beta3) antagonists were prepared on a 2H-1,4-benzoxazine-3(4H)-one scaffold. Their anti-aggregatory activities in human platelet rich plasma and their affinity towards alpha(IIb)beta3 and alpha(V)beta3 integrins were assessed. Various substitution positions and side chain variations were studied. In contrast to the generally accepted model, compounds containing ethyl esters as aspartate mimetics were in general more active than the corresponding free acids. We suggest an explanation for the observed behaviour of these new compounds.

  13. Antagonistic properties of microogranisms associated with cassava ...

    The antagonistic properties of indigenous microflora from cassava starch, flour and grated cassava were investigated using the conventional streak, novel ring and well diffusion methods. Antagonism was measured by zone of inhibition between the fungal plug and bacterial streak/ring. Bacillus species were more effective ...

  14. Carbon adaptation influence the antagonistic ability of ...

    Influences of carbon adaptation on antagonistic activities of three Pseudomonas aeruginosa strains V4, V7 and V10 against Fusarium oxysporum f. sp. melonis were determined in this study. Results from this study showed that the P. aeruginosa strains and their adapted strains significantly inhibited the growth of mycelium ...

  15. Evaluation of GABAergic neuroactive steroid 3alpha-hydroxy-5alpha-pregnane-20-one as a neurobiological substrate for the anti-anxiety effect of ethanol in rats.

    Hirani, Khemraj; Sharma, Ajay N; Jain, Nishant S; Ugale, Rajesh R; Chopde, Chandrabhan T

    2005-07-01

    Acute systemic ethanol administration is known to elevate plasma and cerebral levels of neuroactive steroid 3alpha-hydroxy-5alpha-pregnane-20-one (3alpha, 5alpha-THP; allopregnanolone) to a concentration sufficient to potentiate GABA(A) receptors. We have earlier demonstrated that 3alpha, 5alpha-THP mediates the antidepressant-like effect of ethanol in Porsolt forced swim test. The aim of the present study is to explain the relationship between endogenous GABAergic neurosteroids and anxiolytic effect of ethanol in Sprague-Dawley rats. The mediation of 3alpha, 5alpha-THP in the anti-anxiety effect of ethanol was assessed by pharmacological interactions of ethanol with various endogenous neurosteroidal modulators and using simulated physiological conditions of altered neurosteroid content in elevated plus maze (EPM) test. Pretreatment of 3alpha, 5alpha-THP (0.5-2.5 mug/rat, i.c.v.) or neurosteroidogenic agents such as 3alpha, 5alpha-THP precursor progesterone (5 or 10 mg/kg, i.p.), 11-beta hydroxylase inhibitor metyrapone (50 or 100 mg/kg, i.p.) or the GABA(A) receptor agonist muscimol (25 ng/rat, i.c.v.) significantly potentiated the anti-anxiety effect of ethanol (1 g/kg, i.p.). On the other hand, the GABAergic antagonistic neurosteroid dehydroepiandrosterone sulphate (DHEAS) (1 mg/kg, i.p.), the GABA(A) receptor blocker bicuculline (1 mg/kg, i.p.), the 5alpha-reductase inhibitor finasteride (50 x 2 mg/kg, s.c.) or the mitochondrial diazepam binding inhibitory receptor antagonist PK11195 (1 mg/kg, i.p.) reduced ethanol-induced preference of time spent and number of entries into open arms. Anti-anxiety effect of ethanol was abolished in adrenalectomized (ADX) rats as compared to sham-operated control. This ADX-induced blockade was restored by prior systemic injection of progesterone, signifying the contribution of peripheral steroidogenesis in ethanol anxiolysis. Socially isolated animals known to exhibit decreased brain 3alpha, 5alpha-THP and GABA(A) receptor

  16. Monte Carlo alpha calculation

    Brockway, D.; Soran, P.; Whalen, P.

    1985-01-01

    A Monte Carlo algorithm to efficiently calculate static alpha eigenvalues, N = ne/sup ..cap alpha..t/, for supercritical systems has been developed and tested. A direct Monte Carlo approach to calculating a static alpha is to simply follow the buildup in time of neutrons in a supercritical system and evaluate the logarithmic derivative of the neutron population with respect to time. This procedure is expensive, and the solution is very noisy and almost useless for a system near critical. The modified approach is to convert the time-dependent problem to a static ..cap alpha../sup -/eigenvalue problem and regress ..cap alpha.. on solutions of a/sup -/ k/sup -/eigenvalue problem. In practice, this procedure is much more efficient than the direct calculation, and produces much more accurate results. Because the Monte Carlo codes are intrinsically three-dimensional and use elaborate continuous-energy cross sections, this technique is now used as a standard for evaluating other calculational techniques in odd geometries or with group cross sections.

  17. antagonistic effect of native bacillus isolates against black root rot

    ACSS

    A number of fungi and bacteria are known to be very effective .... Round. Convex. Smooth. Wrinkled. Slow. BS024. Irregular and spreading. Flat. Wavy .... Antibiotic effect of bacterial antagonist ..... antagonistic Bacillus and Trichoderma isolates ...

  18. Role of Peripheral Alpha2 Adrenergic Receptors in Tonic Pain During Different Stages of Estrous Cycle in Rats

    AR Abyazi Shelmani; M Taherianfard

    2007-01-01

    Introduction: Estrogen and progesterone are supposed to modify pain sensitivity. However, the actual role of each of these steroid hormones in this respect is not well known. Plasma concentrations of these hormones show variation during estrous cycle. The role of alpha2 receptors in tonic pain has been pointed out. The aim of the present study was to investigate the agonist and antagonist effect of alpha2 adrenergic receptors on tonic pain sensitivity during all stages of estrous cycle in fem...

  19. Tumor necrosis factor alpha converting enzyme: an encouraging target for various inflammatory disorders.

    Bahia, Malkeet S; Silakari, Om

    2010-05-01

    Tumor necrosis factor alpha is one of the most common pro-inflammatory cytokines responsible for various inflammatory disorders. It plays an important role in the origin and progression of rheumatoid arthritis and also in other autoimmune disease conditions. Some anti-tumor necrosis factor alpha antibodies like Enbrel, Humira and Remicade have been successfully used in these disease conditions as antagonists of tumor necrosis factor alpha. Inhibition of generation of active form of tumor necrosis factor alpha is a promising therapy for various inflammatory disorders. Therefore, the inhibition of an enzyme (tumor necrosis factor alpha converting enzyme), which is responsible for processing inactive form of tumor necrosis factor alpha into its active soluble form, is an encouraging target. Many tumor necrosis factor alpha converting enzyme inhibitors have been the candidates of clinical trials but none of them have reached in to the market because of their broad spectrum inhibitory activity for other matrix metalloproteases. Selectivity of tumor necrosis factor alpha converting enzyme inhibition over matrix metalloproteases is of utmost importance. If selectivity is achieved successfully, side-effects can be over-ruled and this approach may become a novel therapy for treatment of rheumatoid arthritis and other inflammatory disorders. This cytokine not only plays a pivotal role in inflammatory conditions but also in some cancerous conditions. Thus, successful targeting of tumor necrosis factor alpha converting enzyme may result in multifunctional therapy.

  20. Alpha Momentum and Price Momentum

    Hannah Lea Hühn

    2018-05-01

    Full Text Available We analyze a novel alpha momentum strategy that invests in stocks based on three-factor alphas which we estimate using daily returns. The empirical analysis for the U.S. and for Europe shows that (i past alpha has power in predicting the cross-section of stock returns; (ii alpha momentum exhibits less dynamic factor exposures than price momentum and (iii alpha momentum dominates price momentum only in the U.S. Connecting both strategies to behavioral explanations, alpha momentum is more related to an underreaction to firm-specific news while price momentum is primarily driven by price overshooting due to momentum trading.

  1. Alpha Antihydrogen Experiment

    Fujiwara, M C; Ashkezari, M D; Baquero-Ruiz, M; Bertsche, W; Bray, C C; Butler, E; Cesar, C L; Chapman, S; Charlton, M; Cesar, C L; Fajans, J; Friesen, T; Gill, D R; Hangst, J S; Hardy, W N; Hayano, R S; Hayden, M E; Humphries, A J; Hydomako, R; Jonsell, S; Kurchaninov, L; Lambo, R; Madsen, N; Menary, S; Nolan, P; Olchanski, K; Olin, A; Povilus, A; Pusa, P; Robicheaux, F; Sarid, E; Silveira, D M; So, C; Storey, J W; Thompson, R I; van der Werf, D P; Wilding, D; Wurtele, J S; Yamazaki, Y

    2011-01-01

    ALPHA is an experiment at CERN, whose ultimate goal is to perform a precise test of CPT symmetry with trapped antihydrogen atoms. After reviewing the motivations, we discuss our recent progress toward the initial goal of stable trapping of antihydrogen, with some emphasis on particle detection techniques.

  2. Case Study - Alpha

    Stephen Leybourne

    2016-11-01

    Full Text Available This case study was developed from an actual scenario by Dr. Steve Leybourne of Boston University.  The case documents the historical evolution of an organization, and has been used successfully in courses dealing with organizational and cultural change, and the utilization of ‘soft skills’ in project-based management. This is a short case, ideal for classroom use and discussion.  The issues are easily accessible to students, and there is a single wide ranging question that allows for the inclusion of many issues surrounding strategic decision-making, and behavioural and cultural change. Alpha was one of the earlier companies in the USA to invest in large, edge-of-town superstores, with plentiful free vehicle parking, selling food and related household products. Alpha was created in the 1950s as a subsidiary of a major publicly quoted retail group.  It started business by opening a string of very large discount stores in converted industrial and warehouse premises in the south of the United States. In the early days shoppers were offered a limited range of very competitively priced products. When Alpha went public in 1981 it was the fourth largest food retailer in the US, selling an ever-widening range of food and non-food products.  Its success continued to be based on high volume, low margins and good value for money, under the slogan of ‘Alpha Price.’

  3. Alpha-mannosidosis

    Borgwardt, Line; Stensland, Hilde Monica Frostad Riise; Olsen, Klaus Juul

    2015-01-01

    of the three subgroups of genotype/subcellular localisation and the clinical and biochemical data were done to investigate the potential relationship between genotype and phenotype in alpha-mannosidosis. Statistical analyses were performed using the SPSS software. Analyses of covariance were performed...

  4. Bovine alpha-lactalbumin stimulates mucus metabolism in gastric mucosa.

    Ushida, Y; Shimokawa, Y; Toida, T; Matsui, H; Takase, M

    2007-02-01

    Bovine alpha-lactalbumin (alpha-LA), a major milk protein, exerts strong gastroprotective activity against rat experimental gastric ulcers induced by ethanol or stress. To elucidate the mechanisms underlying this activity, the influence of alpha-LA on gastric mucus metabolism was investigated in vitro and in vivo. For the in vitro study, RGM1 cells (a rat gastric epithelial cell line) were selected for observation of the direct activity of alpha-LA on gastric mucosal cells and cultured in the presence of either alpha-LA or ovalbumin (OVA), a reference protein showing no gastroprotective activity. Amounts of synthesized and secreted mucin, a major component of mucus, were determined using [3H]glucosamine as a tracer, and prostaglandin E2 (PGE2) levels in the culture medium were determined by RIA. For the in vivo study, the thickness of the mucus gel layer, a protective barrier for gastric mucosa, was evaluated histochemically in rat gastric mucosa. alpha-Lactalbumin (3 mg/mL) significantly stimulated mucin synthesis and secretion in RGM1 cells and also increased PGE2 levels in the culture medium. In contrast, OVA showed no enhancing effects under identical conditions. Neither indomethacin, a cyclo-oxygenase inhibitor, nor AH23848, a prostaglandin EP4 receptor antagonist, affected alpha-LA-induced enhancement of mucin synthesis and secretion. In vivo, oral administration of alpha-LA (300 mg/kg x 3 times/d x 7 d) increased the thickness of the mucus gel layer in rats. These results indicate that alpha-LA fortifies the mucus gel layer by stimulating mucin production and secretion in gastric mucus-producing cells, and that this enhancing effect is independent of endogenous PGE2. Comparison of the efficacy of alpha-LA with OVA suggests that the activities observed in RGM1 cells are closely related to the gastroprotective effects in rat gastric ulcer models. In conclusion, alpha-LA stimulates mucus metabolism, and this action may be responsible for its gastroprotective

  5. [Tuberculosis in rheumatic patients treated with tumour necrosis factor alpha antagonists: the Portuguese experience].

    Fonseca, João Eurico; Canhão, Helena; Silva, Cândida; Miguel, Cláudia; Mediavilla, Maria Jesus; Teixeira, Ana; Castelão, Walter; Nero, Patrícia; Bernardes, Miguel; Bernardo, Alexandra; Mariz, Eva; Godinho, Fátima; Santos, Maria José; Bogas, Mónica; Oliveira, Margarida; Saavedra, Maria João; Barcelos, Anabela; Cruz, Margarida; Santos, Rui André; Maurício, Luís; Rodrigues, Mário; Figueiredo, Guilherme; Quintal, Alberto; Patto, José Vaz; Malcata, Armando; da Silva, José Canas; Araújo, Domingos; Ventura, Francisco; Branco, Jaime; Queiroz, Mário Viana

    2006-01-01

    In Portugal, 13 cases of tuberculosis (TB) were reported, in the period between 1999 and 2005, in 960 patients exposed to anti-TNFalpha treatment (1.35%), 8 females and 5 males. Mean age was 46.7 +/- 13.8 years. 9 patients had rheumatoid arthritis (RA), in 639 exposed patients (1.4%), 3 had ankylosing spondylitis (AS), in 200 exposed patients (1.5%) and 1 had psoriatic arthritis (PA), in 101 exposed patients (1%). The anti-TNFa used was in 8 cases infliximab (in 456 patients exposed, 1.5%), in 4 adalimumab (in 171 patients exposed, 2.3%) and in 1 etanercept (in 333 exposed, 0.3%). Treatment with a biological agent was started 11.1 +/- 8.7 months (min 3 and max 50) before TB onset. Tuberculin skin test (TST) was performed in 9 out of the 13 patients (the other 4 had started biological therapy before 2002). In 3 cases the TST response was 0 mm, in 3 less than 10 mm, in one was 14 mm and in two 20 mm. In the 3 cases with a TST response superior to 10 mm, isoniazid treatment 300 mg/d was prescribed, during 9 months. The time between first symptoms and TB diagnosis was 2.6 +/- 2.9 months. TB involvement was pulmonary in 6 patients, lymph node disease in 2, peritoneal and pulmonary in 2, osteoarticular in one case, lymph node disease and splenic in another and miliar TB in the last case. One death was reported; all of the other cases had a good outcome after anti-TB treatment. In two cases (one treated with adalimumab and the other with infliximab), paradoxical response to treatment occurred. None of the patients has restarted biological therapy after TB treatment.

  6. Antagonistic parent-offspring co-adaptation.

    Mathias Kölliker

    2010-01-01

    Full Text Available In species across taxa, offspring have means to influence parental investment (PI. PI thus evolves as an interacting phenotype and indirect genetic effects may strongly affect the co-evolutionary dynamics of offspring and parental behaviors. Evolutionary theory focused on explaining how exaggerated offspring solicitation can be understood as resolution of parent-offspring conflict, but the evolutionary origin and diversification of different forms of family interactions remains unclear.In contrast to previous theory that largely uses a static approach to predict how "offspring individuals" and "parental individuals" should interact given conflict over PI, we present a dynamic theoretical framework of antagonistic selection on the PI individuals obtain/take as offspring and the PI they provide as parents to maximize individual lifetime reproductive success; we analyze a deterministic and a stochastic version of this dynamic framework. We show that a zone for equivalent co-adaptation outcomes exists in which stable levels of PI can evolve and be maintained despite fast strategy transitions and ongoing co-evolutionary dynamics. Under antagonistic co-adaptation, cost-free solicitation can evolve as an adaptation to emerging preferences in parents.We show that antagonistic selection across the offspring and parental life-stage of individuals favors co-adapted offspring and parental behavior within a zone of equivalent outcomes. This antagonistic parent-offspring co-adaptation does not require solicitation to be costly, allows for rapid divergence and evolutionary novelty and potentially explains the origin and diversification of the observed provisioning forms in family life.

  7. Radial-velocity variations in Alpha Ori, Alpha Sco, and Alpha Her

    Smith, M.A.; Patten, B.M.; Goldberg, L.

    1989-01-01

    Radial-velocity observations of Alpha Ori, Alpha Sco A, and Alpha Her A are used to study radial-velocity periodicities in M supergiants. The data refer to several metallic lines in the H-alpha region and to H-alpha itself. It is shown that Alpha Ori and Alpha Sco A have cycle lengths of about 1 yr and semiamplitudes of 2 km/s. It is suggested that many semiregular red supergiant varibles such as Alpha Ori may be heading toward chaos. All three stars show short-term stochastic flucutations with an amplitude of 1-2 km/s. It is found that the long-term variability of H-alpha velocities may be a consequence of intermittent failed ejections. 58 refs

  8. Medicinal Chemistry of Competitive Kainate Receptor Antagonists

    2010-01-01

    Kainic acid (KA) receptors belong to the group of ionotropic glutamate receptors and are expressed throughout in the central nervous system (CNS). The KA receptors have been shown to be involved in neurophysiological functions such as mossy fiber long-term potentiation (LTP) and synaptic plasticity and are thus potential therapeutic targets in CNS diseases such as schizophrenia, major depression, neuropathic pain and epilepsy. Extensive effort has been made to develop subtype-selective KA receptor antagonists in order to elucidate the physiological function of each of the five subunits known (GluK1−5). However, to date only selective antagonists for the GluK1 subunit have been discovered, which underlines the strong need for continued research in this area. The present review describes the structure−activity relationship and pharmacological profile for 10 chemically distinct classes of KA receptor antagonists comprising, in all, 45 compounds. To the medicinal chemist this information will serve as reference guidance as well as an inspiration for future effort in this field. PMID:22778857

  9. Pharmacological analysis of calcium antagonist receptors

    Reynolds, I.J.

    1987-01-01

    This work focuses on two aspects of the action of calcium antagonist drugs, namely, the interaction of drugs with receptors for verapamil-like calcium antagonists, and the interactions of drugs with voltage-sensitive calcium fluxes in rat brain synaptosomes. From binding studies I have found that the ligand of choice for labeling the verapamil receptor is (-)[ 3 H]desmethoxy-verapamil. This drug labels potently, reversibly and stereoselectively two receptors in membranes prepared from rat brain and rabbit skeletal muscle tissues. In equilibrium studies dihydropyridine calcium antagonists interact in a non-competitive fashion, while many non-DHPs are apparently competitive. In-depth kinetic studies in skeletal muscle membranes indicate that the two receptors are linked in a negative heterotropic fashion, and that low-affinity binding of (-) [ 3 H]desmethoxy-verapamil may be to the diltiazem receptor. However, these studies were not able to distinguish between the hypothesis that diltiazem binds to spatially separate, allosterically coupled receptors, and the hypothesis that diltiazem binds to a subsite of the verapamil receptor

  10. Potent and long-acting corticotropin releasing factor (CRF) receptor 2 selective peptide competitive antagonists.

    Rivier, J; Gulyas, J; Kirby, D; Low, W; Perrin, M H; Kunitake, K; DiGruccio, M; Vaughan, J; Reubi, J C; Waser, B; Koerber, S C; Martinez, V; Wang, L; Taché, Y; Vale, W

    2002-10-10

    We present evidence that members of the corticotropin releasing factor (CRF) family assume distinct structures when interacting with the CRF(1) and CRF(2) receptors. Predictive methods, physicochemical measurements, and structure-activity relationship studies have suggested that CRF, its family members, and competitive antagonists such as astressin [cyclo(30-33)[DPhe(12),Nle(21),Glu(30),Lys(33),Nle(38)]hCRF((12-41))] assume an alpha-helical conformation when interacting with their receptors. We had shown that alpha-helical CRF((9-41)) and sauvagine showed some selectivity for CRF receptors other than that responsible for ACTH secretion(1) and later for CRF2.(2) More recently, we suggested the possibility of a helix-turn-helix motif around a turn encompassing residues 30-33(3) that would confer high affinity for both CRF(1) and CRF(2)(2,4) in agonists and antagonists of all members of the CRF family.(3) On the other hand, the substitutions that conferred ca. 100-fold CRF(2) selectivity to the antagonist antisauvagine-30 [[DPhe(11),His(12)]sauvagine((11-40))] did not confer such property to the corresponding N-terminally extended agonists. We find here that a Glu(32)-Lys(35) side chain to side chain covalent lactam constraint in hCRF and the corresponding Glu(31)-Lys(34) side chain to side chain covalent lactam constraint in sauvagine yield potent ligands that are selective for CRF(2). Additionally, we introduced deletions and substitutions known to increase duration of action to yield antagonists such as cyclo(31-34)[DPhe(11),His(12),C(alpha)MeLeu(13,39),Nle(17),Glu(31),Lys(34)]Ac-sauvagine((8-40)) (astressin(2)-B) with CRF(2) selectivities greater than 100-fold. CRF receptor autoradiography was performed in rat tissue known to express CRF(2) and CRF(1) in order to confirm that astressin(2)-B could indeed bind to established CRF(2) but not CRF(1) receptor-expressing tissues. Extended duration of action of astressin(2)-B vs that of antisauvagine-30 is demonstrated in

  11. The involvement of peripheral alpha 2-adrenoceptors in the antihyperalgesic effect of oxcarbazepine in a rat model of inflammatory pain.

    Tomić, Maja A; Vucković, Sonja M; Stepanović-Petrović, Radica M; Ugresić, Nenad D; Paranos, Sonja Lj; Prostran, Milica S; Bosković, Bogdan

    2007-11-01

    We studied whether peripheral alpha2-adrenergic receptors are involved in the antihyperalgesic effects of oxcarbazepine by examining the effects of yohimbine (selective alpha2-adrenoceptor antagonist), BRL 44408 (selective alpha(2A)-adrenoceptor antagonist), MK-912 (selective alpha2C-adrenoceptor antagonist), and clonidine (alpha2-adrenoceptor agonist) on the antihyperalgesic effect of oxcarbazepine in the rat model of inflammatory pain. Rats were intraplantarly (i.pl.) injected with the proinflammatory compound concanavalin A (Con A). A paw-pressure test was used to determine: 1) the development of hyperalgesia induced by Con A; 2) the effects of oxcarbazepine (i.pl.) on Con A-induced hyperalgesia; and 3) the effects of i.pl. yohimbine, BRL 44408, MK-912 and clonidine on the oxcarbazepine antihyperalgesia. Both oxcarbazepine (1000-3000 nmol/paw; i.pl.) and clonidine (1.9-7.5 nmol/paw; i.pl.) produced a significant dose-dependent reduction of the paw inflammatory hyperalgesia induced by Con A. Yohimbine (260 and 520 nmol/paw; i.pl.), BRL 44408 (100 and 200 nmol/paw; i.pl.) and MK-912 (10 and 20 nmol/paw; i.pl.) significantly depressed the antihyperalgesic effects of oxcarbazepine (2000 nmol/paw; i.pl.) in a dose-dependent manner. The effects of antagonists were due to local effects since they were not observed after administration into the contralateral hindpaw. Oxcarbazepine and clonidine administered jointly in fixed-dose fractions of the ED(50) (1/4, 1/2, and 3/4) caused significant and dose-dependent reduction of hyperalgesia induced by Con A. Isobolographic analysis revealed an additive antihyperalgesic effect. Our results indicate that the peripheral alpha2A and alpha2C adrenoceptors could be involved in the antihyperalgesic effects of oxcarbazepine in a rat model of inflammatory hyperalgesia.

  12. Resting alpha activity predicts learning ability in alpha neurofeedback

    Wenya eNan

    2014-07-01

    Full Text Available Individuals differ in their ability to learn how to regulate the alpha activity by neurofeedback. This study aimed to investigate whether the resting alpha activity is related to the learning ability of alpha enhancement in neurofeedback and could be used as a predictor. A total of 25 subjects performed 20 sessions of individualized alpha neurofeedback in order to learn how to enhance activity in the alpha frequency band. The learning ability was assessed by three indices respectively: the training parameter changes between two periods, within a short period and across the whole training time. It was found that the resting alpha amplitude measured before training had significant positive correlations with all learning indices and could be used as a predictor for the learning ability prediction. This finding would help the researchers in not only predicting the training efficacy in individuals but also gaining further insight into the mechanisms of alpha neurofeedback.

  13. Alpha scintillation radon counting

    Lucas, H.F. Jr.

    1977-01-01

    Radon counting chambers which utilize the alpha-scintillation properties of silver activated zinc sulfide are simple to construct, have a high efficiency, and, with proper design, may be relatively insensitive to variations in the pressure or purity of the counter filling. Chambers which were constructed from glass, metal, or plastic in a wide variety of shapes and sizes were evaluated for the accuracy and the precision of the radon counting. The principles affecting the alpha-scintillation radon counting chamber design and an analytic system suitable for a large scale study of the 222 Rn and 226 Ra content of either air or other environmental samples are described. Particular note is taken of those factors which affect the accuracy and the precision of the method for monitoring radioactivity around uranium mines

  14. AlphaACT

    2014-07-20

    and other ADT data As part of Task 2, AlphaTRAC: • Collaborated with CERDEC and the U.S. Military Academy Network Sciences Center to develop...example) Meehl (1954) and Swets, Dawes, and Monahan (2000), which convincingly explain how actuarial judgments rendered by statistical models tend to...Reasoning (DARPA), Morgan Kaufmann Publishers, San Mateo, CA. Swcts, J.A., Dawes, R.M., and Monahan, J. (2000). Better decisions through science

  15. Rossi Alpha Method

    Hansen, G.E.

    1985-01-01

    The Rossi Alpha Method has proved to be valuable for the determination of prompt neutron lifetimes in fissile assemblies having known reproduction numbers at or near delayed critical. This workshop report emphasizes the pioneering applications of the method by Dr. John D. Orndoff to fast-neutron critical assemblies at Los Alamos. The value of the method appears to disappear for subcritical systems where the Rossi-α is no longer an α-eigenvalue

  16. Combination decongestion therapy in hospitalized heart failure: loop diuretics, mineralocorticoid receptor antagonists and vasopressin antagonists.

    Vaduganathan, Muthiah; Mentz, Robert J; Greene, Stephen J; Senni, Michele; Sato, Naoki; Nodari, Savina; Butler, Javed; Gheorghiade, Mihai

    2015-01-01

    Congestion is the most common reason for admissions and readmissions for heart failure (HF). The vast majority of hospitalized HF patients appear to respond readily to loop diuretics, but available data suggest that a significant proportion are being discharged with persistent evidence of congestion. Although novel therapies targeting congestion should continue to be developed, currently available agents may be utilized more optimally to facilitate complete decongestion. The combination of loop diuretics, natriuretic doses of mineralocorticoid receptor antagonists and vasopressin antagonists represents a regimen of currently available therapies that affects early and persistent decongestion, while limiting the associated risks of electrolyte disturbances, hemodynamic fluctuations, renal dysfunction and mortality.

  17. Role of alpha2C-adrenoceptor subtype in spatial working memory as revealed by mice with targeted disruption of the alpha2C-adrenoceptor gene.

    Tanila, H; Mustonen, K; Sallinen, J; Scheinin, M; Riekkinen, P

    1999-02-01

    The role of the alpha2C-adrenoceptor subtype in mediating the beneficial effect of alpha2-adrenoceptor agonists on spatial working memory was studied in adult mice with targeted inactivation of the alpha2C-receptor gene (KO) and their wild-type controls (WT). A delayed alternation task was run in a T-maze with mixed delays varying from 20 s to 120 s. Dexmedetomidine, a specific but subtype nonselective alpha2-adrenoceptor agonist, dose-dependently decreased the total number of errors. The effect was strongest at the dose of 5 microg/kg (s.c.), and was observed similarly in KO and WT mice. KO mice performed inferior to WT mice due to a higher number of perseverative errors. Dexmedetomidine slowed initiation of the motor response in the start phase at lower doses in WT mice than in KO mice but no such difference was observed in the return phase of the task, suggesting involvement of alpha2C-adrenoceptors in the cognitive aspect of response preparation or in response sequence initiation. According to these findings, enhancement of spatial working memory is best achieved with alpha2-adrenoceptor agonists which have neither agonistic nor antagonistic effects at the alpha2C-adrenoceptor subtype.

  18. Anticonvulsant and reproductive toxicological studies of the imidazole-based histamine H3R antagonist 2-18 in mice

    Bastaki SM

    2018-01-01

    Full Text Available Salim M Bastaki,1 Yousef M Abdulrazzaq,2 Mohamed Shafiullah,1 Małgorzata Więcek,3 Katarzyna Kieć-Kononowicz,3 Bassem Sadek1 1Department of Pharmacology and Therapeutics, College of Medicine and Health Science, United Arab Emirates University, Al Ain, 2Department of Medical Education, Dubai Health Authority, Dubai, UAE; 3Department of Technology and Biotechnology of Drugs, Faculty of Pharmacy, Jagiellonian University Medical College, Medyczna, Kraków, Poland Abstract: The imidazole-based H3R antagonist 2-18 with high in vitro H3R antagonist affinity, excellent in vitro selectivity profile, and high in vivo H3R antagonist potency was tested for its anticonvulsant effect in maximal electroshock (MES-induced convulsions in mice having valproic acid (VPA as a reference antiepileptic drug (AED. Additionally, H3R antagonist 2-18 was evaluated for its reproductive toxicity in the same animal species. The results show that acute systemic administration (intraperitoneal; i.p. of H3R antagonist 2-18 (7.5, 15, 30, and 60 mg/kg, i.p. significantly and dose dependently protected male as well as female mice against MES-induced convulsion. The protective action observed for H3R antagonist 2-18 in both mice sexes was comparable to that of VPA and was reversed when mice were pretreated with the selective H3R agonist (R-alpha-methylhistamine (RAMH, 10 mg/kg, i.p.. Moreover, the results show that acute systemic administration of single (7.5, 15, 30, or 60 mg/kg, i.p. or multiple doses (15×3 mg/kg, i.p. of H3R antagonist 2-18 on gestation day (GD 8 or 13 did not affect the maternal body weight of mice when compared with the control group. Furthermore, no significant differences were observed in the average number of implantations and resorptions between the control and H3R antagonist 2-18-treated group at the early stages of gestation and the organogenesis period. However, oral treatment with H3R antagonist 2-18 (15 mg/kg on GD 8 induced a reduced number of

  19. Combining Alphas via Bounded Regression

    Zura Kakushadze

    2015-11-01

    Full Text Available We give an explicit algorithm and source code for combining alpha streams via bounded regression. In practical applications, typically, there is insufficient history to compute a sample covariance matrix (SCM for a large number of alphas. To compute alpha allocation weights, one then resorts to (weighted regression over SCM principal components. Regression often produces alpha weights with insufficient diversification and/or skewed distribution against, e.g., turnover. This can be rectified by imposing bounds on alpha weights within the regression procedure. Bounded regression can also be applied to stock and other asset portfolio construction. We discuss illustrative examples.

  20. Combined effects of alpha particles and depleted uranium on Zebrafish (Danio rerio) embryos

    Ng, Candy Y.P.; Pereira, Sandrine; Cheng, Shuk Han; Adam-Guillermin, Christelle; Garnier-Laplace, Jacqueline; Yu, Kwan Ngok

    2016-01-01

    The combined effects of low-dose or high-dose alpha particles and depleted uranium (DU) in Zebrafish (Danio rerio) embryos were studied. Three schemes were examined—(i) [I L U L ]: 0.44 mGy alpha-particle dose + 10 µg/l DU exposure, (ii) [I H U H ]: 4.4 mGy alpha-particle dose + 100 µg/l DU exposure and (iii) [I H U L ]: 4.4 mGy alpha-particle dose + 10 µg/l DU exposure—in which Zebrafish embryos were irradiated with alpha particles at 5 h post fertilization (hpf) and/or exposed to uranium at 5–6 hpf. The results were also compared with our previous work, which studied the effects of [I L U H ]: 0.44 mGy alpha-particle dose + 100 µg/l DU exposure. When the Zebrafish embryos developed to 24 hpf, the apoptotic signals in the entire embryos, used as the biological endpoint for this study, were quantified. Our results showed that [I L U L ] and [I H U L ] led to antagonistic effects, whereas [I H U H ] led to an additive effect. The effect found for the previously studied case of [I L U H ] was difficult to define because it was synergistic with reference to the 100 µg/l DU exposure, but it was antagonistic with reference to the 0.44 mGy alpha-particle dose. All the findings regarding the four different schemes showed that the combined effects critically depended on the dose response to each individual stressor. We also qualitatively explained these findings in terms of promotion of early death of cells predisposed to spontaneous transformation by alpha particles, interacting with the delay in cell death resulting from various concentrations of DU exposure

  1. Sexually antagonistic selection in human male homosexuality.

    Andrea Camperio Ciani

    Full Text Available Several lines of evidence indicate the existence of genetic factors influencing male homosexuality and bisexuality. In spite of its relatively low frequency, the stable permanence in all human populations of this apparently detrimental trait constitutes a puzzling 'Darwinian paradox'. Furthermore, several studies have pointed out relevant asymmetries in the distribution of both male homosexuality and of female fecundity in the parental lines of homosexual vs. heterosexual males. A number of hypotheses have attempted to give an evolutionary explanation for the long-standing persistence of this trait, and for its asymmetric distribution in family lines; however a satisfactory understanding of the population genetics of male homosexuality is lacking at present. We perform a systematic mathematical analysis of the propagation and equilibrium of the putative genetic factors for male homosexuality in the population, based on the selection equation for one or two diallelic loci and Bayesian statistics for pedigree investigation. We show that only the two-locus genetic model with at least one locus on the X chromosome, and in which gene expression is sexually antagonistic (increasing female fitness but decreasing male fitness, accounts for all known empirical data. Our results help clarify the basic evolutionary dynamics of male homosexuality, establishing this as a clearly ascertained sexually antagonistic human trait.

  2. Hypocretin antagonists in insomnia treatment and beyond.

    Ruoff, Chad; Cao, Michelle; Guilleminault, Christian

    2011-01-01

    Hypocretin neuropeptides have been shown to regulate transitions between wakefulness and sleep through stabilization of sleep promoting GABAergic and wake promoting cholinergic/monoaminergic neural pathways. Hypocretin also influences other physiologic processes such as metabolism, appetite, learning and memory, reward and addiction, and ventilatory drive. The discovery of hypocretin and its effect upon the sleep-wake cycle has led to the development of a new class of pharmacologic agents that antagonize the physiologic effects of hypocretin (i.e. hypocretin antagonists). Further investigation of these agents may lead to novel therapies for insomnia without the side-effect profile of currently available hypnotics (e.g. impaired cognition, confusional arousals, and motor balance difficulties). However, antagonizing a system that regulates the sleep-wake cycle while also influencing non-sleep physiologic processes may create an entirely different but equally concerning side-effect profile such as transient loss of muscle tone (i.e. cataplexy) and a dampened respiratory drive. In this review, we will discuss the discovery of hypocretin and its receptors, hypocretin and the sleep-wake cycle, hypocretin antagonists in the treatment of insomnia, and other implicated functions of the hypocretin system.

  3. Alpha-Amylase Activity in Blood Increases after Pharmacological, But Not Psychological, Activation of the Adrenergic System.

    Urs M Nater

    Full Text Available Alpha-amylase in both blood and saliva has been used as a diagnostic parameter. While studies examining alpha-amylase activity in saliva have shown that it is sensitive to physiological and psychological challenge of the adrenergic system, no challenge studies have attempted to elucidate the role of the adrenergic system in alpha-amylase activity in blood. We set out to examine the impact of psychological and pharmacological challenge on alpha-amylase in blood in two separate studies.In study 1, healthy subjects were examined in a placebo-controlled, double-blind paradigm using yohimbine, an alpha2-adrenergic antagonist. In study 2, subjects were examined in a standardized rest-controlled psychosocial stress protocol. Alpha-amylase activity in blood was repeatedly measured in both studies.Results of study 1 showed that alpha-amylase in blood is subject to stronger increases after injection of yohimbine compared to placebo. In study 2, results showed that there was no significant effect of psychological stress compared to rest.Alpha-amylase in blood increases after pharmacological activation of the adrenergic pathways suggesting that sympathetic receptors are responsible for these changes. Psychological stress, however, does not seem to have an impact on alpha-amylase in blood. Our findings provide insight into the mechanisms underlying activity changes in alpha-amylase in blood in healthy individuals.

  4. Treatment of alpha bearing wastes

    1988-01-01

    This report deals with the current state of the art of alpha waste treatment, which is an integral part of the overall nuclear waste management system. The International Atomic Energy Agency (IAEA) defines alpha bearing waste as 'waste containing one or more alpha emitting radionuclides, usually actinides, in quantities above acceptable limits'. The limits are established by national regulatory bodies. The limits above which wastes are considered as alpha contaminated refer to the concentrations of alpha emitters that need special consideration for occupational exposures and/or potential safety, health, or environmental impact during one or more steps from generation through disposal. Owing to the widespread use of waste segregation by source - that is, based upon the 'suspect origin' of the material - significant volumes of waste are being handled as alpha contaminated which, in fact, do not require such consideration by reason of risk or environmental concern. The quantification of de minimis concepts by national regulatory bodies could largely contribute to the safe reduction of waste volumes and associated costs. Other factors which could significantly contribute to the reduction of alpha waste arisings are an increased application of assaying and sorting, instrumentation and the use of feedback mechanisms to control or modify the processes which generate these wastes. Alpha bearing wastes are generated during fabrication and reprocessing of nuclear fuels, decommissioning of alpha contaminated facilities, and other activities. Most alpha wastes are contact handled, but a small portion may require shielding or remote handling because of high levels of neutron (n), beta (β), or gamma (γ) emissions associated with the waste material. This report describes the sources and characteristics of alpha wastes and strategies for alpha waste management. General descriptions of treatment processes for solid and liquid alpha wastes are included. 71 refs, 14 figs, 9 tabs

  5. Bi209 alpha activity

    Araujo Penna, M.M. de.

    1970-01-01

    The study for measuring Bi 209 alpha activity is presented. Ilford L4 nuclear emulsion pellicles loaded with bismuth citrate to obtain a load of 100 mg/cm 3 of dry emulsion, were prepared. Other pellicles were prepared with the same. Ilford L4 gel to estimate the background radiation. To observe 'fading' effect, pellicles loaded with bismuth were submitted to neutrons of high energy, aiming to record recoil proton tracks. The pellicles were confined in nitrogen atmosphere at temperature lower than -10 0 C. The Bi 209 experimental half-life was obtained and compared with the estimated theoretical data. (M.C.K.) [pt

  6. Alpha-mannosidosis

    Nilssen Øivind

    2008-07-01

    Full Text Available Abstract Alpha-mannosidosis is an inherited lysosomal storage disorder characterized by immune deficiency, facial and skeletal abnormalities, hearing impairment, and intellectual disability. It occurs in approximately 1 of 500,000 live births. The children are often born apparently normal, and their condition worsens progressively. Some children are born with ankle equinus or develop hydrocephalus in the first year of life. Main features are immune deficiency (manifested by recurrent infections, especially in the first decade of life, skeletal abnormalities (mild-to-moderate dysostosis multiplex, scoliosis and deformation of the sternum, hearing impairment (moderate-to-severe sensorineural hearing loss, gradual impairment of mental functions and speech, and often, periods of psychosis. Associated motor function disturbances include muscular weakness, joint abnormalities and ataxia. The facial trait include large head with prominent forehead, rounded eyebrows, flattened nasal bridge, macroglossia, widely spaced teeth, and prognathism. Slight strabismus is common. The clinical variability is significant, representing a continuum in severity. The disorder is caused by lysosomal alpha-mannosidase deficiency. Alpha-mannosidosis is inherited in an autosomal recessive fashion and is caused by mutations in the MAN2B1 gene located on chromosome 19 (19 p13.2-q12. Diagnosis is made by measuring acid alpha-mannosidase activity in leukocytes or other nucleated cells and can be confirmed by genetic testing. Elevated urinary secretion of mannose-rich oligosaccharides is suggestive, but not diagnostic. Differential diagnoses are mainly the other lysosomal storage diseases like the mucopolysaccharidoses. Genetic counseling should be given to explain the nature of the disease and to detect carriers. Antenatal diagnosis is possible, based on both biochemical and genetic methods. The management should be pro-active, preventing complications and treating

  7. The alpha effect

    Anon.

    1982-01-01

    Much of the recent interest in RAM system reliability stems from concern over alpha particle soft error rates reported for the initial 64 k RAMs. With increasing memory density likely in the next few years the problem of soft errors is rearing its head again. A few years ago ITT carried out experiments on 16k RAMs and found no significant problems. However, recent tests have shown a raise in the number of soft errors with 64k RAMs, and the launch of 256k and 512k memories is likely to make the problem acute

  8. History of the 'geste antagoniste' sign in cervical dystonia.

    Poisson, A; Krack, P; Thobois, S; Loiraud, C; Serra, G; Vial, C; Broussolle, E

    2012-08-01

    The geste antagoniste is a voluntary maneuver that temporarily reduces the severity of dystonic posture or movements. It is a classical feature of focal and particularly cervical dystonia. However, the precise historical aspects of geste antagoniste still remain obscure. The goals of this review were (1) to clarify the origin of the geste antagoniste sign; (2) to identify the factors that led to its diffusion in the international literature; (3) to follow the evolution of that term across the twentieth century. We used medical and neurological French, German and English literature of the late nineteenth and early twentieth centuries, and the PubMed database by entering the terms geste antagoniste, antagonistic gesture and sensory trick. The geste antagoniste sign is a legacy of the Paris Neurological School of the end of the nineteenth century. The term was introduced by Meige and Feindel in their 1902 book on tics, written in the vein of their master, Brissaud, who first described this sign in 1893. The almost immediate translations of this book by Giese into German and Kinnier Wilson into English contributed to the rapid spreading of the term geste antagoniste, which is still in use worldwide today. The term antagonistic gesture is the translation proposed by Kinnier Wilson, which also led to the use of the term geste antagonistique. The geste antagoniste sign has long been considered a solid argument for the psychogenic origins of dystonia until the 1980s when Marsden made strong arguments for its organic nature.

  9. The Attractiveness of Opposites: Agonists and Antagonists.

    O'Brien, Tony

    2015-02-02

    ABSTRACT Opioid-induced bowel dysfunction, of which constipation is the most common aspect, is a major limiting factor in the use of opioids for pain management. The availability of an oral, long-acting formulation of oxycodone and naloxone represents a highly significant development in pain management. The combination of an opioid analgesic with an opioid antagonist offers reliable pain control with a significant reduction in the burden of opioid-induced constipation. This report is adapted from paineurope 2014; Issue 3, ©Haymarket Medical Publications Ltd, and is presented with permission. paineurope is provided as a service to pain management by Mundipharma International, LTD and is distributed free of charge to healthcare professionals in Europe. Archival issues can be accessed via the website: http:\\/\\/www.paineurope.com at which European health professionals can register online to receive copies of the quarterly publication.

  10. Antiallergic effects of H1-receptor antagonists.

    Baroody, F M; Naclerio, R M

    2000-01-01

    The primary mechanism of antihistamine action in the treatment of allergic diseases is believed to be competitive antagonism of histamine binding to cellular receptors (specifically, the H1-receptors), which are present on nerve endings, smooth muscles, and glandular cells. This notion is supported by the fact that structurally unrelated drugs antagonize the H1-receptor and provide clinical benefit. However, H1-receptor antagonism may not be their sole mechanism of action in treating allergic rhinitis. On the basis of in vitro and animal experiments, drugs classified as H1-receptor antagonists have long been recognized to have additional pharmacological properties. Most first-generation H1-antihistamines have anticholinergic, sedative, local anaesthetic, and anti-5-HT effects, which might favourably affect the symptoms of the allergic response but also contribute to side-effects. These additional properties are not uniformly distributed among drugs classified as H1-receptor antagonists. Azatadine, for example, inhibits in vitro IgE-mediated histamine and leukotriene (LT) release from mast cells and basophils. In human challenge models, terfenadine, azatadine, and loratadine reduce IgE-mediated histamine release. Cetirizine reduces eosinophilic infiltration at the site of antigen challenge in the skin, but not the nose. In a nasal antigen challenge model, cetirizine pretreatment did not affect the levels of histamine and prostaglandin D2 recovered in postchallenge lavages, whereas the levels of albumin, N-tosyl-L-arginine methyl ester (TAME) esterase activity, and LTs were reduced. Terfenadine, cetirizine, and loratadine blocked allergen-induced hyperresponsiveness to methacholine. In view of the complexity of the pathophysiology of allergy, a number of H1 antagonists with additional properties are currently under development for allergic diseases. Mizolastine, a new H1-receptor antagonist, has been shown to have additional actions that should help reduce the

  11. Antagonistic activity of marine sponges associated Actinobacteria

    Selvakumar Dharmaraj

    2016-06-01

    Full Text Available Objective: To focus on the isolation and preliminary characterization of marine sponges associated Actinobacteria particularly Streptomyces species and also their antagonistic activities against bacterial and fungal pathogens. Methods: The sponges were collected from Kovalam and Vizhinjam port of south-west coast of Kerala, India. Isolation of strains was carried out from sponge extracts using international Streptomyces project media. For preliminary identification of the strains, morphological (mycelial colouration, soluble pigments, melanoid pigmentation, spore morphology, nutritional uptake (carbon utilisation, amonoacids influence, sodium chloride tolerance, physiological (pH, temperature and chemotaxonomical characterization were done. Antimicrobial studies were also carried out for the selected strains. Results: With the help of the spicule structures, the collected marine sponges were identified as Callyspongia diffusa, Mycale mytilorum, Tedania anhelans and Dysidea fragilis. Nearly 94 strains were primarily isolated from these sponges and further they were sub-cultured using international Streptomyces project media. The strains exhibited different mycelial colouration (aerial and substrate, soluble and melanoid pigmentations. The strains possessed three types of sporophore morphology namely rectus flexibilis, spiral and retinaculiaperti. Among the 94 isolates, seven exhibited antibacterial and antifungal activities with maximal zone of inhibition of 30 mm. The nutritional, physiological and chemotaxonomical characteristic study helped in the conventional identification of the seven strains and they all suggest that the strains to be grouped under the genus Streptomyces. Conclusions: The present study clearly helps in the preliminary identification of the isolates associated with marine sponges. Antagonistic activities prove the production of antimicrobial metabolites against the pathogens. Marine sponges associated Streptomyces are

  12. Assay method for organic calcium antagonist drugs and a kit for such an assay

    Snyder, S. H.; Gould, R. J.

    1985-01-01

    A method for measuring the level of organic calcium antagonist drug in a body fluid comprises preparing a mixture of a radioactive calcium antagonist drug, a body fluid containing a calcium antagonist drug and a calcium antagonist receptor material, measuring the radioactivity of the radioactive calcium antagonist drug bound to said calcium antagonist receptor material and deriving the concentration of the calcium antagonist drug in the body fluid from a standard curve indicating the concentration of calcium antagonist drug versus inhibition of binding of said radioactive calcium antagonist drug to said receptor sites caused by the calcium antagonist drug in said body fluid. A kit for measuring the level of an organic calcium drug comprises a receptacle containing a radioactive calcium antagonist drug, a calcium antagonist receptor material and a standard amount of a nonradioactive calcium antagonist drug

  13. Distribution of alpha3, alpha5 and alpha(v) integrin subunits in mature and immature human oocytes.

    Capmany, G; Mart, M; Santaló, J; Bolton, V N

    1998-10-01

    The distribution of three integrin subunits, alpha3, alpha5 and alpha(v), in immature and mature human oocytes has been examined using immunofluorescence and confocal microscopy. The results demonstrate that both alpha5 and alpha(v) are present at the germinal vesicle stage, while alpha3 was only detected in oocytes after germinal vesicle breakdown, in metaphase I and II stage oocytes. The cortical concentration of integrin subunits alpha3 and alpha5 is consistent with their localization in the oolemma. In contrast, the homogeneous distribution of alpha(v) throughout the oocyte suggests the existence of cytoplasmic reservoirs of this protein in the oocyte.

  14. Hypothermic and antipyretic effects of ACTH (1-24) and alpha-melanotropin in guinea-pigs

    Kandasamy, S. B.; Williams, B. A.

    1984-01-01

    Intracerebroventricular administration of adrenocorticotropin (ACTH 1-24) and alpha-melanotropin (alpha-MSH), peptides which occur naturally in brain induced dose-related hypothermia in guinea-pigs at room temperature (21 C) and also produced greater hypothermia at low (10 C) ambient temperature. However, when the experiments were repeated in a warm (30 C) environment, no effect on body temperature was observed. These results indicate that the peptides did not reduce the central set-point of temperature control. The hypothermia induced by ACTH and alpha-MSH was not mediated via histamine H1- or H2-receptors and serotonin since the H1-receptor antagonist, mepyramine, the H2-receptor antagonist, cimetidine, and the serotonin antagonist, methysergide, had no antagonistic effects. The peptides were antipyretic since they reduced pyrogen-induced-fever and hyperthermia due to prostaglandin E2, norepinephrine and dibutyryl cAMP, at a dose which did not affect normal body temperature. The powerful central effects of these peptides on normal body temperature, fever and hyperthermia, together with their presence of the brain regions important to temperature control, suggest that they participate in thermoregulation.

  15. Synthesis and characterization of arylamine derivatives of rauwolscine as molecular probes for alpha 2-adrenergic receptors

    Lanier, S.M.; Graham, R.M.; Hess, H.J.; Grodski, A.; Repaske, M.G.; Nunnari, J.M.; Limbird, L.E.; Homcy, C.J.

    1987-01-01

    The selective alpha 2-adrenergic receptor antagonist rauwolscine was structurally modified to yield a series of arylamine carboxamide derivatives, which were investigated as potential molecular probes for the localization and structural characterization of alpha 2-adrenergic receptors. The arylamine carboxamides differ in the number of carbon atoms separating the reactive phenyl moiety from the fused ring structure of the parent compound, rauwolscine carboxylate. Competitive inhibition studies with [ 3 H]rauwolscine in rat kidney membranes indicate that the affinity for the carboxamide derivatives is inversely related to the length of the carbon spacer arm with rauwolscine 4-aminophenyl carboxamide exhibiting the highest affinity (Kd = 2.3 +/- 0.2 nM). Radioiodination of rau-AMPC yields a ligand, 125 I-rau-AMPC, which binds to rat kidney alpha 2-adrenergic receptors with high affinity, as determined by both kinetic analysis (Kd = k2/k1 = 0.016 min-1/2.1 X 10(7) M-1 min-1 = 0.76 nM) and equilibrium binding studies (Kd = 0.78 +/- 0.16 nM). 125 I-rau-AMPC was quantitatively converted to the photolabile arylazide derivative 17 alpha-hydroxy-20 alpha-yohimban-16 beta-(N-4-azido-3-[ 125 I]iodophenyl) carboxamide ( 125 I-rau-AZPC). In a partially purified receptor preparation from porcine brain, this compound photolabels a major (Mr = 62,000) peptide. The labeling of this peptide is inhibited by adrenergic agonists and antagonists with a rank order of potency consistent with an alpha 2-adrenergic receptor binding site. Both 125 I-rau-AMPC and the photolabile arylazide derivative, 125 I-rau-AZPC, should prove useful as molecular probes for the structural and biochemical characterization of alpha 2-adrenergic receptors

  16. Production of interleukin-1alpha by human endometrial stromal cells is triggered during menses and dysfunctional bleeding and is induced in culture by epithelial interleukin-1alpha released upon ovarian steroids withdrawal.

    Pretto, Chrystel M; Gaide Chevronnay, Héloïse P; Cornet, Patricia B; Galant, Christine; Delvaux, Denis; Courtoy, Pierre J; Marbaix, Etienne; Henriet, Patrick

    2008-10-01

    Endometrial breakdown during menstruation and dysfunctional bleeding is triggered by the abrupt expression of matrix metalloproteinases (MMPs), including interstitial collagenase (MMP-1). The paracrine induction of MMP-1 in stromal cells via epithelium-derived IL-1alpha is repressed by ovarian steroids. However, the control by estradiol (E) and progesterone (P) of endometrial IL-1alpha expression and bioactivity remains unknown. Variations of endometrial IL-1alpha mRNA and protein along the menstrual cycle and during dysfunctional bleeding were determined using RT-PCR, in situ hybridization, and immunolabeling. The mechanism of EP control was analyzed using culture of explants, laser capture microdissection, and purified cells. Data were compared with expression changes of IL-1beta and IL-1 receptor antagonist. IL-1alpha is synthesized by epithelial cells throughout the cycle but E and/or P prevents its release. In contrast, endometrial stromal cells produce IL-1alpha only at menses and during irregular bleeding in areas of tissue breakdown. Stromal expression of IL-1alpha, like that of MMP-1, is repressed by P (alone or with E) but triggered by epithelium-derived IL-1alpha released upon EP withdrawal. Our experiments in cultured endometrium suggest that IL-1alpha released by epithelial cells triggers the production of IL-1alpha by stromal cells in a paracrine amplification loop to induce MMP-1 expression during menstruation and dysfunctional bleeding. All three steps of this amplification cascade are repressed by EP.

  17. ALPHA/AMPU, Radionuclide Radioactivity from Alpha Spectrometer Measurements

    Sill, D.S.

    1990-01-01

    1 - Description of program or function: The two computer programs, ALPHA and AMPU, take raw data obtained from alpha spectrometry and from these calculate activities and uncertainties of the radionuclides present in the sample. ALPHA determines activities of any alpha emitter in a sample that has been directly precipitated with NdF 3 . AMPU determines the Pu-239, Pu-238,and Am-241 activities using Pu-236 and Am-243 tracers. 2 - Method of solution: These programs propagate all random and systematic uncertainties, found anywhere in the experimental process, to the final result. The result is rounded and is in decimal agreement with the uncertainty. 3 - Restrictions on the complexity of the problem: In ALPHA, a chemical yield of 98% is assumed

  18. Thrombin-receptor antagonist vorapaxar in acute coronary syndromes

    Tricoci, Pierluigi; Huang, Zhen; Held, Claes

    2012-01-01

    Vorapaxar is a new oral protease-activated-receptor 1 (PAR-1) antagonist that inhibits thrombin-induced platelet activation.......Vorapaxar is a new oral protease-activated-receptor 1 (PAR-1) antagonist that inhibits thrombin-induced platelet activation....

  19. Antagonistic and Bargaining Games in Optimal Marketing Decisions

    Lipovetsky, S.

    2007-01-01

    Game theory approaches to find optimal marketing decisions are considered. Antagonistic games with and without complete information, and non-antagonistic games techniques are applied to paired comparison, ranking, or rating data for a firm and its competitors in the market. Mix strategy, equilibrium in bi-matrix games, bargaining models with…

  20. Vitamin K antagonist use and mortality in dialysis patients

    Voskamp, Pauline W.M.; Rookmaaker, Maarten B.; Verhaar, Marianne C.; Dekker, Friedo W.; Ocak, Gurbey

    2018-01-01

    Background. The risk-benefit ratio of vitamin K antagonists for different CHA2DS2-VASc scores in patients with end-stage renal disease treated with dialysis is unknown. The aim of this study was to investigate the association between vitamin K antagonist use and mortality for different CHA2DS2-VASc

  1. Evaluation of antagonistic fungi against charcoal rot of sunflower ...

    In vitro, sensitivity of Macrophomina phaseolina (Tassi) Goid determined through inhibition zone technique to various antagonistic fungi viz., Aspergillus niger, Aspergillus flavus, Trichoderma viride, Trichoderma harzianum and Penicillium capsulatum amended into PDA medium. All the antagonists reduced the colony ...

  2. Alpha wastes treatment

    Thouvenot, P.

    2000-01-01

    Alter 2004, the alpha wastes issued from the Commissariat a l'Energie Atomique installations will be sent to the CEDRA plant. The aims of this installation are decontamination and wastes storage. Because of recent environmental regulations concerning ozone layer depletion, the use of CFC 113 in the decontamination unit, as previously planned, is impossible. Two alternatives processes are studied: the AVD process and an aqueous process including surfactants. Best formulations for both processes are defined issuing degreasing kinetics. It is observed that a good degreasing efficiency is linked to a good decontamination efficiency. Best results are obtained with the aqueous process. Furthermore, from the point of view of an existing waste treatment unit, the aqueous process turns out to be more suitable than the AVD process. (author)

  3. Alpha spectrometry without chemistry

    Murray, A.S.; Heaton, B.

    1983-01-01

    A gridded cylindrical pulse ionization chamber is considered for the simultaneous analysis of natural alpha emitters. Solid sources of up to 0.3 g are deposited after wet grinding as a thin layer on 1.1 m 2 of aluminized plastic film, which acts as the cathode. No chemistry is involved, and thus there is little chance of nuclide fractionation. With a ''weightless'' source the resolution is about 55 keV; 110 keV has been easily achieved at 4.2 MeV with real sources. We conclude that significant information about isotope activities in the natural series is available with only a fraction of the work involved in conventional techniques. (author)

  4. Stimulant effects of adenosine antagonists on operant behavior: differential actions of selective A2A and A1 antagonists

    Randall, Patrick A.; Nunes, Eric J.; Janniere, Simone L.; Stopper, Colin M.; Farrar, Andrew M.; Sager, Thomas N.; Baqi, Younis; Hockemeyer, Jörg; Müller, Christa E.

    2012-01-01

    Rationale Adenosine A2A antagonists can reverse many of the behavioral effects of dopamine antagonists, including actions on instrumental behavior. However, little is known about the effects of selective adenosine antagonists on operant behavior when these drugs are administered alone. Objective The present studies were undertaken to investigate the potential for rate-dependent stimulant effects of both selective and nonselective adenosine antagonists. Methods Six drugs were tested: two nonselective adenosine antagonists (caffeine and theophylline), two adenosine A1 antagonists (DPCPX and CPT), and two adenosine A2A antagonists (istradefylline (KW6002) and MSX-3). Two schedules of reinforcement were employed; a fixed interval 240-s (FI-240 sec) schedule was used to generate low baseline rates of responding and a fixed ratio 20 (FR20) schedule generated high rates. Results Caffeine and theophylline produced rate-dependent effects on lever pressing, increasing responding on the FI-240 sec schedule but decreasing responding on the FR20 schedule. The A2A antagonists MSX-3 and istradefylline increased FI-240 sec lever pressing but did not suppress FR20 lever pressing in the dose range tested. In fact, there was a tendency for istradefylline to increase FR20 responding at a moderate dose. A1 antagonists failed to increase lever pressing rate, but DPCPX decreased FR20 responding at higher doses. Conclusions These results suggest that adenosine A2A antagonists enhance operant response rates, but A1 antagonists do not. The involvement of adenosine A2A receptors in regulating aspects of instrumental response output and behavioral activation may have implications for the treatment of effort-related psychiatric dysfunctions, such as psychomotor slowing and anergia in depression. PMID:21347642

  5. Central alpha2 adrenergic receptors in the rat cerebral cortex: repopulation kinetics and receptor reserve

    Adler, C.H.

    1986-01-01

    The alpha 2 adrenergic receptor subtype is thought to play a role in the mechanism of action of antidepressant and antihypertensive drugs. This thesis has attempted to shed light on the regulation of central alpha 2 adrenergic receptors in the rat cerebral cortex. Repopulation kinetics analysis allows for the determination of the rate of receptor production, rate constant of degradation, and half-life of the receptor. This analysis was carried out using both radioligand binding and functional receptor assays at various times following the irreversible inactivation of central alpha 2 adrenergic receptors by in vivo administration of N-ethoxycarbonyl-2-ethyoxy-1,2-dihydroquinoline (EEDQ). Both alpha 2 agonist and antagonist ligand binding sites recovered with a t/sub 1/2/ equal to approximately 4 days. The function of alpha 2 adrenergic autoreceptors, which inhibit stimulation-evoked release of 3 H-norepinephrine ( 3 H-NE) and alpha 2 adrenergic heteroreceptors which inhibit stimulation-evoked release of 3 H-serotonin ( 3 H-5-HT) were assayed. The t/sub 1/2/ for recovery of maximal autoreceptor and heteroreceptor function was 2.4 days and 4.6 days, respectively. The demonstration of a receptor reserve is critical to the interpretation of past and future studies of the alpha 2 adrenergic receptor since it demonstrates that: (1) alterations in the number of alpha 2 adrenergic receptor binding sites cannot be extrapolated to the actual function of the alpha 2 adrenergic receptor; and (2) alterations in the number of alpha 2 receptors is not necessarily accompanied by a change in the maximum function being studied, but may only result in shifting of the dose-response curve

  6. In vitro study of alpha 2-adrenoceptor turnover and metabolism using the adenocarcinoma cell line HT29

    Paris, H.; Taouis, M.; Galitzky, J.

    1987-01-01

    The biosynthesis rate of the receptor was studied in postconfluent HT29 cells, when its density expressed as fmol/mg of cell membrane protein is constant, by following the recovery of the receptor binding capacity after blockade with the non-reversible alpha-adrenergic antagonist benextramine. Study of the inhibition of [ 3 H]yohimbine and [ 3 H]UK-14,304 binding showed that benextramine was a more potent antagonist at alpha 2-adrenoceptor than phenoxybenzamine. The incubation of intact HT29 cells for 30 min in the presence of 10(-5) M benextramine irreversibly blocked more than 95% of the alpha 2-adrenoceptors and totally suppressed the inhibitory effect of UK-14,304 on cyclic AMP production. The blockade appeared specific, since benextramine effects were prevented by alpha 2-adrenergic agents. Moreover, neither vasoactive intestinal polypeptide responsiveness nor other tested aspects of the regulation of the adenylate cyclase was altered by the treatment. Study of the time course of receptor recovery after irreversible blockade indicated that alpha 2-adrenoceptors reappeared in the cells with a monoexponential kinetic. The linearization of the repopulation curve obtained with the labeled antagonist [ 3 H]yohimbine allowed the determination of the rate constant for receptor degradation (k = 0.0268 +/- 0.0025 hr-1) and the rate of receptor synthesis (6.91 +/- 0.64 fmol/mg of cell membrane protein/hr) corresponding to the synthesis of about 500 receptors/cell/hr. The alpha 2-adrenoceptor half-life was 26 +/- 3 hr. Measurement of the biological effects associated to the alpha-adrenoceptor stimulation during the course of receptor recovery indicated a relationship between the number of cell receptors and the percentage of inhibition of the cyclic AMP accumulation induced by forskolin

  7. Alpha particle emitters in medicine

    Fisher, D.R.

    1989-09-01

    Radiation-induced cancer of bone, liver and lung has been a prominent harmful side-effect of medical applications of alpha emitters. In recent years, however, the potential use of antibodies labeled with alpha emitting radionuclides against cancer has seemed promising because alpha particles are highly effective in cell killing. High dose rates at high LET, effectiveness under hypoxic conditions, and minimal expectancy of repair are additional advantages of alpha emitters over antibodies labeled with beta emitting radionuclides for cancer therapy. Cyclotron-produced astatine-211 ( 211 At) and natural bismuth-212 ( 212 Bi) have been proposed and are under extensive study in the United States and Europe. Radium-223 ( 223 Ra) also has favorable properties as a potential alpha emitting label, including a short-lived daughter chain with four alpha emissions. The radiation dosimetry of internal alpha emitters is complex due to nonuniformly distributed sources, short particle tracks, and high relative specific ionization. The variations in dose at the cellular level may be extreme. Alpha-particle radiation dosimetry, therefore, must involve analysis of statistical energy deposition probabilities for cellular level targets. It must also account fully for nonuniform distributions of sources in tissues, source-target geometries, and particle-track physics. 18 refs., 4 figs

  8. Proteinaceous alpha-araylase inhibitors

    Svensson, Birte; Fukuda, Kenji; Nielsen, P.K.

    2004-01-01

    -amylase inhibitors belong to seven different protein structural families, most of which also contain evolutionary related proteins without inhibitory activity. Two families include bifunctional inhibitors acting both on alpha-amylases and proteases. High-resolution structures are available of target alpha...

  9. Mind Your p's and Alphas.

    Stallings, William M.

    In the educational research literature alpha, the a priori level of significance, and p, the a posteriori probability of obtaining a test statistic of at least a certain value when the null hypothesis is true, are often confused. Explanations for this confusion are offered. Paradoxically, alpha retains a prominent place in textbook discussions of…

  10. The ALPHA antihydrogen trapping apparatus

    Amole, C. [Department of Physics and Astronomy, York University, Toronto ON Canada, M3J 1P3 (Canada); Andresen, G.B. [Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C (Denmark); Ashkezari, M.D. [Department of Physics, Simon Fraser University, Burnaby, BC Canada, V5A 1S6 (Canada); Baquero-Ruiz, M. [Department of Physics, University of California at Berkeley, Berkeley, CA 94720-7300 (United States); Bertsche, W. [Department of Physics, College of Science, Swansea University, Swansea SA2 8PP (United Kingdom); School of Physics and Astronomy, University of Manchester, Manchester M13 9PL (United Kingdom); The Cockcroft Institute, Warrington WA4 4AD (United Kingdom); Bowe, P.D. [Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C (Denmark); Butler, E. [Physics Department, CERN, CH-1211 Geneva 23 (Switzerland); Capra, A. [Department of Physics and Astronomy, York University, Toronto ON Canada, M3J 1P3 (Canada); Carpenter, P.T. [Department of Physics, Auburn University, Auburn, AL 36849-5311 (United States); Cesar, C.L. [Instituto de Física, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-972 (Brazil); Chapman, S. [Department of Physics, University of California at Berkeley, Berkeley, CA 94720-7300 (United States); Charlton, M.; Deller, A.; Eriksson, S. [Department of Physics, College of Science, Swansea University, Swansea SA2 8PP (United Kingdom); Escallier, J. [Brookhaven National Laboratory, Upton, NY 11973 (United States); Fajans, J. [Department of Physics, University of California at Berkeley, Berkeley, CA 94720-7300 (United States); Friesen, T. [Department of Physics and Astronomy, University of Calgary, Calgary AB, Canada, T2N 1N4 (Canada); Fujiwara, M.C.; Gill, D.R. [TRIUMF, 4004 Wesbrook Mall, Vancouver BC, Canada V6T 2A3 (Canada); Gutierrez, A. [Department of Physics and Astronomy, University of British Columbia, Vancouver BC, Canada V6T 1Z4 (Canada); and others

    2014-01-21

    The ALPHA collaboration, based at CERN, has recently succeeded in confining cold antihydrogen atoms in a magnetic minimum neutral atom trap and has performed the first study of a resonant transition of the anti-atoms. The ALPHA apparatus will be described herein, with emphasis on the structural aspects, diagnostic methods and techniques that have enabled antihydrogen trapping and experimentation to be achieved.

  11. The Lyman alpha reference sample

    Hayes, M.; Östlin, G.; Schaerer, D.

    2013-01-01

    We report on new imaging observations of the Lyman alpha emission line (Lyα), performed with the Hubble Space Telescope, that comprise the backbone of the Lyman alpha Reference Sample. We present images of 14 starburst galaxies at redshifts 0.028

  12. Insurance - Piper Alpha ''et al''

    Hales, K.

    1995-01-01

    This paper opens with some brief information about the Piper Alpha loss, how the loss was handled and its final cost. More importantly, it discusses the effect of the Piper Alpha loss on the world insurance market including the oil insurance captives such as O.I.L Limited. Finally, the insurance market current status and prognosis for the future are considered. (Author)

  13. Long-range alpha detector

    MacArthur, D.W.; McAtee, J.L.

    1991-01-01

    Historically, alpha-particle and alpha-contamination detectors have been limited by the very short range of alpha particles in air and by relatively poor sensitivity even if the particles are intercepted. Alpha detectors have had to be operated in a vacuum or in close proximity to the source if reasonable efficiency is desired. Alpha particles interact with the ambient air, producing ionization in the air at the rate of ∼30,000 ion pairs per mega-electron-volt of alpha energy. These charges can be transported over significant distances (several meters) in a moving current of air generated by a small fan. An ion chamber located in front of the fan measures the current carried by the moving ions. The long-range alpha detector (LRAD) offers several advantages over more traditional alpha detectors. First and foremost, it can operate efficiently even if the contamination is not easily accessible. Second, ions generated by contamination in crevices and other unmonitorable locations can be detected if the airflow penetrates those areas. Third, all of the contamination on a large surface will generate ions that can be detected in a single detector; hence, the detector's sensitivity to distributed sources is not limited by the size of the probe. Finally, a simple ion chamber can detect very small electric currents, making this technique potentially quite sensitive

  14. Current position of 5HT3 antagonists and the additional value of NK1 antagonists; a new class of antiemetics

    R. de Wit (Ronald)

    2003-01-01

    textabstractThe advent of the 5HT3 receptor antagonists (5HT3 antagonists) in the 1990s and the combination with dexamethasone has resulted in acute emesis protection in 70% of patients receiving highly emetogenic chemotherapy. Despite complete protection in the acute phase, however, 40% of patients

  15. Protection against cyanide-induced convulsions with alpha-ketoglutarate.

    Yamamoto, H

    1990-04-30

    Protection against convulsions induced by cyanide was observed after treatment with alpha-ketoglutarate, either alone or in combination with sodium thiosulfate, a classical antagonist for cyanide intoxication. However, sodium thiosulfate alone did not protect against cyanide (30 mg/kg)-induced convulsions. gamma-Aminobutyric acid (GABA) levels in brain were decreased by 31% in KCN-treated mice exhibiting convulsions. The combined administration of alpha-ketoglutarate and sodium thiosulfate completely abolished the decrease of GABA levels induced by cyanide. Furthermore, sodium thiosulfate alone also completely abolished the decrease of GABA levels. These results suggest that the depletion of brain GABA levels may not directly contribute to the development of convulsions induced by cyanide. On the other hand, cyanide increased calcium levels by 32% in brain crude mitochondrial fractions in mice with convulsions. The increased calcium levels were completely abolished by the combined administration of alpha-ketoglutarate and sodium thiosulfate, but not affected by sodium thiosulfate alone. These findings support the hypothesis proposed by Johnson et al. (Toxicol. Appl. Pharmacol., 84 (1986) 464) and Robinson et al. (Toxicology, 35 (1985) 59) that calcium may play an important role in mediating cyanide neurotoxicity.

  16. Alpha 2-adrenoceptor blockade, pituitary-adrenal hormones, and agonistic interactions in rats.

    Haller, J; Barna, I; Kovács, J L

    1994-08-01

    The effects of adrenergic activation on aggressiveness and the aggression induced endocrine changes were tested in rats. Alpha 2 adrenoceptor blockers were used for enhancing activation of the adrenergic system, and changes in aggressiveness were tested in resident-intruder contests. Three experiments were conducted. In experiment 1, saline injected rats responded to the presence of an opponent by aggression and the increase in plasma ACTH and corticosterone. Intraperitoneal administration of 1 mg/kg CH-38083 (an alpha 2 adrenoceptor antagonist) produced a several fold increase in clinch fighting and mutual upright scores, and also further enhanced the plasma ACTH and corticosterone response. In experiment 2, the effect of three doses (0.5, 1 and 2 mg/kg) of three different alpha 2 adrenoceptor blockers CH-38083, idazoxan and yohimbine were tested. All the substances increased aggression at 0.5 and 1 mg/kg; at 2 mg/kg the effect of idazoxan and yohimbine disappeared, while with CH-38083 an additional increase was obtained. In yohimbine treated animals the enhancement of aggression was reduced already at 1 mg/kg. In experiment 3, indomethacin, a potent inhibitor of the catecholamine-induced ACTH release completely abolished the effects of the alpha 2 adrenoceptor antagonist CH-38083: the intensity of agonistic interactions, as well as ACTH and corticosterone plasma concentrations, returned to control levels. The possible role of catecholamines and the stress hormones in the activation of aggression is discussed.

  17. Novel high-throughput screening system for identifying STAT3-SH2 antagonists

    Uehara, Yutaka; Mochizuki, Masato; Matsuno, Kenji; Haino, Takeharu; Asai, Akira

    2009-01-01

    Constitutive activation of the oncogenic transcription factor STAT3 frequently occurs in various human malignancies. STAT3 activation involves dimerization via intermolecular pTyr-SH2 interaction. Thus, antagonizing this interaction is a feasible approach to inhibit STAT3 activation for cancer therapy. In order to identify selective STAT3 inhibitors, we developed a biochemical HTS system based on AlphaScreen technology, which measures the abilities of test compounds to antagonize pTyr-SH2 interactions. We screened our chemical libraries using this system and identified 5,15-diphenylporphyrin (5,15-DPP) as a selective STAT3-SH2 antagonist. Selective inhibition of STAT3 nuclear translocation and DNA biding activity was observed in cells treated with 5,15-DPP. IL-6-dependent dimerization of STAT3, c-myc promoter binding and c-myc protein expression were all suppressed by 5,15-DPP, whereas no decrement in either expression or phosphorylation level of STAT3 was observed. Thus, the HTS assay system represented herein may be useful for identifying novel STAT3-SH2 antagonists.

  18. Preclinical anticonvulsant and neuroprotective profile of 8319, a non-competitive NMDA antagonist

    Fielding, S.; Wilker, J.C.; Chernack, J.; Ramirez, V.; Wilmot, C.A.; Martin, L.L.; Payack, J.F.; Cornfeldt, M.L.; Rudolphi, K.A.; Rush, D.K.

    1990-01-01

    8319, ((+-)-2-Amino-N-ethyl-alpha-(3-methyl-2-thienyl)benzeneethanamine 2HCl), is a novel compound with the profile of a non-competitive NMDA antagonist. The compound displaced [3H] TCP with high affinity (IC50 = 43 nM), but was inactive at the NMDA, benzodiazepine and GABA sites; in vivo, 8319 showed good efficacy as an anticonvulsant and potential neuroprotective agent. It blocked seizures induced by NMDLA, supramaximal electroshock, pentylenetetrazol (PTZ), picrotoxin, and thiosemicarbazide with ED50's of 1-20 mg/kg ip. As a neuroprotective agent, 8319 (30-100 mg/kg sc) prevented the death of dorsal hippocampal pyramidal cells induced by direct injection of 20 nmol NMDA. At 15 mg/kg ip, the compound was also effective against hippocampal neuronal necrosis induced via bilateral occlusion of the carotid arteries in gerbils. In summary, 8319 is a noncompetitive NMDA antagonist with good anticonvulsant activity and may possess neuroprotective properties useful in the treatment of brain ischemia

  19. The effect of different classes of beta-antagonists on clinical and experimental hypertension.

    Fitzgerald, J D

    1982-01-01

    The reference beta adrenoceptor antagonist propranolol reduces blood pressure in about 60% of patients with essential hypertension. Pressure is reduced in the supine, and erect positions without postural hypotension as well as during exercise. The average extent of pressure reduction is approximately 26/16 mm.Hg. Though all clinically available beta antagonists reduce blood pressure, the profile may be modified by both adrenotropic and non-adrenotropic ancillary properties. Of the adrenotropic properties, potency influences dose frequency and total body burden of drug. Selective beta 1 antagonism may enhance safety without reducing efficacy in patients with obstructive airways disease. Selective beta 2 blockade does not reduce blood pressure in experimental models or normal subjects, but the response in patients is unknown. Partial agonism may reduce efficacy if the degree of stimulant activity is too great. Of the non-adrenotropic properties, membrane stabilising properties are of relevance only in so far as such agents undergo extensive biotransformation resulting in either reduced efficacy when drugs are used at fixed doses or the formation of biologically active metabolites. The additional properties of either alpha adrenergic blockade or inhibition of vascular smooth muscle tone modify both the speed of onset and the haemodynamic profile. The interaction of these ancillary pharmacological properties is evaluated in this review.

  20. Effects of local anesthetics on cholinergic agonist binding affinity of central nervous system. cap alpha. -bungarotoxin receptors

    Lukas, R.L.; Bennett, E.L.

    1979-12-01

    In general, pharmacological effects of local anesthetics may be attributed to their ability to reversibly block the propagation of nerve and muscle action potentials. At physiologically potent concentrations, local anesthetics (LA) also act as noncompetitive antagonists of the physiological response of post-synaptic nicotinic acetylcholine receptors (nAChR) to cholinergic agonists, and increase agonist binding affinities of nAChR from electric organ. It is postulated that the primary site of LA action on nAChR function is at the receptor-coupled ionophore. Furthermore, LA-nAChR ionophore interactions are thought to accelerate physiological desensitization of nAChR, manifest biochemically as increased affinity of nAChR for agonist. Specific receptors for ..cap alpha..-bungarotoxin (..cap alpha..-Bgt), a potent competitive antagonist at nAChR sites in the periphery, have been detected in rat central nervous system membrane preparations. The affinity of these central ..cap alpha..-Bgt receptors (..cap alpha..-BgtR) for cholinergic agonists is found to increase on exposure to agonist. Nevertheless, on the basis of inconsistent pharmacological and physiological results, uncertainty remains regarding the relationship between ..cap alpha..-BgtR and authentic nAChR in the CNS, despite a wide body of biochemical and histological evidence consistent with their identity. Reasoning that if CNS ..cap alpha..-BgtR are true in nAChR, coupled to functional ion channels, LA might be expected to cause biochemically measurable increases in ..cap alpha..-BgtR affinity for cholinergic agonists, we have undertaken a study of the effects of LA on the ability of acetylcholine (ACh) to inhibit interaction of ..cap alpha..-BgtR with /sup 3/H-labeled ..cap alpha..-Bgt.

  1. Antagonistic neural networks underlying differentiated leadership roles

    Boyatzis, Richard E.; Rochford, Kylie; Jack, Anthony I.

    2014-01-01

    The emergence of two distinct leadership roles, the task leader and the socio-emotional leader, has been documented in the leadership literature since the 1950s. Recent research in neuroscience suggests that the division between task-oriented and socio-emotional-oriented roles derives from a fundamental feature of our neurobiology: an antagonistic relationship between two large-scale cortical networks – the task-positive network (TPN) and the default mode network (DMN). Neural activity in TPN tends to inhibit activity in the DMN, and vice versa. The TPN is important for problem solving, focusing of attention, making decisions, and control of action. The DMN plays a central role in emotional self-awareness, social cognition, and ethical decision making. It is also strongly linked to creativity and openness to new ideas. Because activation of the TPN tends to suppress activity in the DMN, an over-emphasis on task-oriented leadership may prove deleterious to social and emotional aspects of leadership. Similarly, an overemphasis on the DMN would result in difficulty focusing attention, making decisions, and solving known problems. In this paper, we will review major streams of theory and research on leadership roles in the context of recent findings from neuroscience and psychology. We conclude by suggesting that emerging research challenges the assumption that role differentiation is both natural and necessary, in particular when openness to new ideas, people, emotions, and ethical concerns are important to success. PMID:24624074

  2. Antagonistic Neural Networks Underlying Differentiated Leadership Roles

    Richard Eleftherios Boyatzis

    2014-03-01

    Full Text Available The emergence of two distinct leadership roles, the task leader and the socio-emotional leader, has been documented in the leadership literature since the 1950’s. Recent research in neuroscience suggests that the division between task oriented and socio-emotional oriented roles derives from a fundamental feature of our neurobiology: an antagonistic relationship between two large-scale cortical networks -- the Task Positive Network (TPN and the Default Mode Network (DMN. Neural activity in TPN tends to inhibit activity in the DMN, and vice versa. The TPN is important for problem solving, focusing of attention, making decisions, and control of action. The DMN plays a central role in emotional self-awareness, social cognition, and ethical decision making. It is also strongly linked to creativity and openness to new ideas. Because activation of the TPN tends to suppress activity in the DMN, an over-emphasis on task oriented leadership may prove deleterious to social and emotional aspects of leadership. Similarly, an overemphasis on the DMN would result in difficulty focusing attention, making decisions and solving known problems. In this paper, we will review major streams of theory and research on leadership roles in the context of recent findings from neuroscience and psychology. We conclude by suggesting that emerging research challenges the assumption that role differentiation is both natural and necessary, in particular when openness to new ideas, people, emotions, and ethical concerns are important to success.

  3. Antagonistic neural networks underlying differentiated leadership roles.

    Boyatzis, Richard E; Rochford, Kylie; Jack, Anthony I

    2014-01-01

    The emergence of two distinct leadership roles, the task leader and the socio-emotional leader, has been documented in the leadership literature since the 1950s. Recent research in neuroscience suggests that the division between task-oriented and socio-emotional-oriented roles derives from a fundamental feature of our neurobiology: an antagonistic relationship between two large-scale cortical networks - the task-positive network (TPN) and the default mode network (DMN). Neural activity in TPN tends to inhibit activity in the DMN, and vice versa. The TPN is important for problem solving, focusing of attention, making decisions, and control of action. The DMN plays a central role in emotional self-awareness, social cognition, and ethical decision making. It is also strongly linked to creativity and openness to new ideas. Because activation of the TPN tends to suppress activity in the DMN, an over-emphasis on task-oriented leadership may prove deleterious to social and emotional aspects of leadership. Similarly, an overemphasis on the DMN would result in difficulty focusing attention, making decisions, and solving known problems. In this paper, we will review major streams of theory and research on leadership roles in the context of recent findings from neuroscience and psychology. We conclude by suggesting that emerging research challenges the assumption that role differentiation is both natural and necessary, in particular when openness to new ideas, people, emotions, and ethical concerns are important to success.

  4. Dronerarone acts as a selective inhibitor of 3,5,3'-triiodothyronine binding to thyroid hormone receptor-alpha1: in vitro and in vivo evidence

    van Beeren, H. C.; Jong, W. M. C.; Kaptein, E.; Visser, T. J.; Bakker, O.; Wiersinga, W. M.

    2003-01-01

    Dronedarone (Dron), without iodine, was developed as an alternative to the iodine-containing antiarrhythmic drug amiodarone (AM). AM acts, via its major metabolite desethylamiodarone, in vitro and in vivo as a thyroid hormone receptor alpha(1) (TRalpha(1)) and TRbeta(1) antagonist. Here we

  5. ALPHA freezes antiprotons

    CERN Bulletin

    2010-01-01

    Laboratories like CERN can routinely produce many different types of antiparticles. In 1995, the PS210 experiment formed the first antihydrogen atoms and a few years later, in 2002, ATRAP and ATHENA were already able to produce several thousand of them. However, no experiment in the world has succeeded in ‘trapping’ these anti-atoms in order to study them. This is the goal of the ALPHA experiment, which has recently managed to cool down the antiprotons to just a few Kelvin. This represents a major step towards trapping the anti-atom, thus opening a new avenue into the investigation of antimatter properties.   Members of the ALPHA collaboration working on the apparatus in the Antiproton Decelerator experimental hall at CERN. Just like the atom, the anti-atom is neutral. Unlike the atom, the anti-atom is made up of antiprotons (as opposed to protons in the atom) and positrons (as opposed to electrons). In order to thoroughly study the properties of the anti-atoms, scien...

  6. Alpha detection on moving surfaces

    MacArthur, D.; Orr, C.; Luff, C.

    1998-01-01

    Both environmental restoration (ER) and decontamination and decommissioning (D and D) require characterization of large surface areas (walls, floors, in situ soil, soil and rubble on a conveyor belt, etc.) for radioactive contamination. Many facilities which have processed alpha active material such as plutonium or uranium require effective and efficient characterization for alpha contamination. Traditional methods for alpha surface characterization are limited by the short range and poor penetration of alpha particles. These probes are only sensitive to contamination located directly under the probe. Furthermore, the probe must be held close to the surface to be monitored in order to avoid excessive losses in the ambient air. The combination of proximity and thin detector windows can easily cause instrument damage unless extreme care is taken. The long-range alpha detection (LRAD) system addresses these problems by detecting the ions generated by alpha particles interacting with ambient air rather than the alpha particle directly. Thus, detectors based on LRAD overcome the limitations due to alpha particle range (the ions can travel many meters as opposed to the several-centimeter alpha particle range) and penetrating ability (an LRAD-based detector has no window). Unfortunately, all LRAD-based detectors described previously are static devices, i.e., these detectors cannot be used over surfaces which are continuously moving. In this paper, the authors report on the first tests of two techniques (the electrostatic ion seal and the gridded electrostatic LRAD detector) which extend the capabilities of LRAD surface monitors to use over moving surfaces. This dynamic surface monitoring system was developed jointly by Los Alamos National Laboratory and at BNFL Instruments. All testing was performed at the BNFL Instruments facility in the UK

  7. Multiple Targeting Approaches on Histamine H3 Receptor Antagonists

    Mohammad eKhanfar

    2016-05-01

    Full Text Available With the very recent market approval of pitolisant (Wakix®, the interest in clinical applications of novel multifunctional histamine H3 receptor antagonists has clearly increased. Since histamine H3 receptor antagonists in clinical development have been tested for a variety of different indications, the combination of pharmacological properties in one molecule for improved pharmacological effects and reduced unwanted side-effects is rationally based on the increasing knowledge on the complex neurotransmitter regulations. The polypharmacological approaches on histamine H3 receptor antagonists on different G-protein coupled receptors, transporters, enzymes as well as on NO-signaling mechanism are described, supported with some lead structures.

  8. Alpha heating in toroidal devices

    Miley, G.H.

    1978-01-01

    Ignition (or near-ignition) by alpha heating is a key objective for the achievement of economic fusion reactors. While good confinement of high-energy alphas appears possible in larger reactors, near-term tokamak-type ignition experiments as well as some concepts for small reactors (e.g., the Field-Reversed Mirror or FRM) potentially face marginal situations. Consequently, there is a strong motivation to develop methods to evaluate alpha losses and heating profiles in some detail. Such studies for a TFTR-size tokamak and for a small FRM are described here

  9. Regulation and function of the alpha2 adrenergic autoreceptor in the central nervous system

    Spengler, R.N.

    1987-01-01

    The purpose of this investigation was to determine whether changes observed in the number of alpha 2 adrenergic receptors in the brain as measured by radioligand binding experiments reflect changes in the function of alpha 2 autoregulatory receptors which are located on noradrenergic nerve terminals. Inhibition by clonidine of field stimulated 3 H-norepinephrine ( 3 H-NE) release from rat hippocampal slices before and after several drug treatments was analyzed to investigate changes in alpha 2 adrenergic receptor function. Clonidine in a concentration-dependent manner inhibited 3 H-NE release. The effect of clonidine was blocked by the specific alpha 2 adrenergic receptor antagonist, idazoxan. The cumulative administration of clonidine generated a smooth and well-fitted log-concentration-effect curve. Results are presented which demonstrate that this technique can be employed to investigate the role of changes in the function of the alpha 2 autoregulatory receptor. The present investigation also examined representatives of four drug classes which have been shown to alter the specific binding of 3 H-clonidine to neural membranes to determine whether changes in the alpha 2 autoregulatory receptor function also occur

  10. Impact of the Tamsulosin in Alpha Adrenergic Receptor of Airways at Patients with Increased Bronchial Reactibility.

    Mustafa, Lirim; Ilazi, Ali; Dauti, Arta; Islami, Pellumb; Kastrati, Bashkim; Islami, Hilmi

    2015-08-01

    In this work, effect of tamsulosin as antagonist of alpha1A and alpha1B adrenergic receptor and effect of agonists of beta2 adrenergic receptor-salbutamol in patients with increased bronchial reactibility was studied. Parameters of the lung function are determined with Body plethysmography six (6) hours after administration of tamsulosin. Raw and ITGV were registered and specific resistance (SRaw) was calculated as well. Tamsulosin was administered in per os manner as a preparation in the shape of the capsules with a brand name of "Prolosin", produced by Niche Generics Limited, Hitchin, Herts. After six (6) hours of administration of tamsulosin, results gained indicate that blockage of alpha1A and alpha1B-adrenergic receptor (0.8 mg per os) has not changed significantly (p > 0.1) the bronchomotor tonus of tracheobronchial tree in comparison to the check-up that has inhaled salbutamol agonist of adrenergic beta2 receptor (2 inh. x 0.2 mg), (p tamsulosin. This suggests that even after six hours of administration of tamsulosin, and determining of lung function parameters, the activity of alpha1A and alpha1B-adrenergic receptor in the smooth bronchial musculature has not changed in patients with increased bronchial reactibility.

  11. 2'-O-methyl-modified RNAs act as TLR7 antagonists.

    Robbins, Marjorie; Judge, Adam; Liang, Lisa; McClintock, Kevin; Yaworski, Ed; MacLachlan, Ian

    2007-09-01

    RNA molecules such as single-stranded RNA (ssRNA) and small interfering RNA (siRNA) duplexes induce Toll-like receptor (TLR)-mediated immune stimulation after intracellular delivery. We have previously shown that selective incorporation of 2'-O-methyl (2'OMe) residues into siRNA abrogates cytokine production without reduction of gene silencing activity. Here we show that 2'OMe-modified RNA acts as a potent inhibitor of RNA-mediated cytokine induction in both human and murine systems. This activity does not require the direct incorporation of 2'OMe nucleotides into the immunostimulatory RNA or that the 2'OMe nucleotide-containing RNA be annealed as a complementary strand to form a duplex. Our results indicate that 2'OMe RNA acts as a potent antagonist of immunostimulatory RNA. We further show that 2'OMe RNA is able significantly to reduce both interferon-alpha (IFN-alpha) and interleukin-6 (IL-6) induction by the small-molecule TLR7 agonist loxoribine in human peripheral blood mononuclear cells (human PBMCs), in murine Flt3L dendritic cells (Flt3L DCs), and in vivo in mice. These results indicate that 2'OMe-modified RNA may have utility as an inhibitor of TLR7 with potential applications in the treatment of inflammatory and autoimmune diseases that involve TLR7-mediated immune stimulation.

  12. Regge poles and alpha scattering

    Ceuleneer, R.

    1974-01-01

    The direct Regge pole model as a means of describing resonances in elastic particle scattering has been used for the analysis of the so-called ''anormalous large angle scattering'' of alpha particles by spinless nuclei. (Z.M.)

  13. A SELECTIVE ANTAGONIST OF MINERALOCORTICOID RECEPTOR EPLERENONE IN CARDIOLOGY PRACTICE

    B. B. Gegenava

    2015-01-01

    Full Text Available The role of aldosterone in pathophysiological processes is considered. The effects of the selective antagonist of mineralocorticoid receptor eplerenone are analyzed. The advantages of eplerenone compared with spironolactone are discussed.

  14. Characterization and design of antagonistic shape memory alloy actuators

    Georges, T; Brailovski, V; Terriault, P

    2012-01-01

    Antagonistic shape memory actuators use opposing shape memory alloy (SMA) elements to create devices capable of producing differential motion paths and two-way mechanical work in a very efficient manner. There is no requirement for additional bias elements to ‘re-arm’ the actuators and allow repetitive actuation. The work generation potential of antagonistic shape memory actuators is determined by specific SMA element characteristics and their assembly conditions. In this study, the selected SMA wires are assembled in antagonistic configuration and characterized using a dedicated test bench to evaluate their stress–strain characteristics as a function of the number of cycles. Using these functional characteristics, a so-called ‘working envelope’ is built to assist in the design of such an actuator. Finally, the test bench is used to simulate a real application of an antagonistic actuator (case study). (paper)

  15. Liquid scintillation alpha spectrometry techniques

    McKlveen, J.W.; McDowell, W.J.

    1984-01-01

    Accurate, quantitative determinations of alpha emitting nuclides by conventional plate counting methods are difficult, because of sample self-absorption problems in counting and because of non-reproducible losses in conventional sample separation methods. Liquid scintillation alpha spectrometry offers an attractive alternative with no sample self-absorption or geometry problems and with 100% counting efficiency. Sample preparation may include extraction of the alpha emitter of interest by a specific organic phase-soluble compound directly into the liquid scintillation counting medium. Detection electronics use energy and pulse-shape discrimination, to yield alpha spectra without beta and gamma background interference. Specific procedures have been developed for gross alpha, uranium, plutonium, thorium and colonium assay. Possibilities for a large number of other applications exist. Accuracy and reproducibility are typically in the 1% range. Backgrounds of the order of 0.01 cpm are readily achievable. The paper will present an overview of liquid scintillation alpha counting techniques and some of the results achieved for specific applications. (orig.)

  16. 5-HT7 Receptor Antagonists with an Unprecedented Selectivity Profile.

    Ates, Ali; Burssens, Pierre; Lorthioir, Olivier; Lo Brutto, Patrick; Dehon, Gwenael; Keyaerts, Jean; Coloretti, Francis; Lallemand, Bénédicte; Verbois, Valérie; Gillard, Michel; Vermeiren, Céline

    2018-04-23

    Selective leads: In this study, we generated a new series of serotonin 5-HT 7 receptor antagonists. Their synthesis, structure-activity relationships, and selectivity profiles are reported. This series includes 5-HT 7 antagonists with unprecedented high selectivity for the 5-HT 7 receptor, setting the stage for lead optimization of drugs acting on a range of neurological targets. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Effects of the pesticide amitraz and its metabolite BTS 27271 on insulin and glucagon secretion from the perfused rat pancreas: involvement of alpha2D-adrenergic receptors.

    Abu-Basha, E A; Yibchok-Anun, S; Hopper, D L; Hsu, W H

    1999-11-01

    The study purpose was to investigate the direct effect of amitraz, a formamidine insecticide/acaricide, and its active metabolite BTS 27271 on insulin and glucagon secretion from the perfused rat pancreas. Amitraz and BTS 27271 (0.01, 0.1, 1, and 10 micromol/L) inhibited insulin secretion in a concentration-dependent manner. Amitraz increased glucagon secretion at 10 micromol/L, whereas BTS 27271 increased glucagon secretion at 1 and 10 micromol/L. Amitraz- and BTS 27271-induced decreases in insulin secretion and increases in glucagon secretion were not abolished during the 10-minute washout period. During the arginine treatment, both amitraz and BTS 27271 groups (0.1, 1, and 10 micromol/L) had lower insulin secretion and higher glucagon secretion than the control group. Idazoxan, an alpha2A/2D-adrenergic receptor (AR) antagonist, prevented the inhibitory effect of amitraz on insulin secretion in a concentration-dependent manner, but prazosin, an alpha1- and alpha2B/2C-AR antagonist, failed to antagonize the effect of amitraz. These results demonstrate that (1) amitraz and BTS 27271 inhibit insulin and stimulate glucagon secretion from the perfused rat pancreas, (2) amitraz inhibits insulin secretion by activation of alpha2D-ARs, since rats have alpha2D- but not alpha2A-ARs, and (3) amitraz and BTS 27271 may have a high binding affinity to the alpha2D-ARs of pancreatic islets.

  18. alpha7 and non-alpha7 nicotinic acetylcholine receptors modulate dopamine release in vitro and in vivo in the rat prefrontal cortex.

    Livingstone, Phil D; Srinivasan, Jayaraman; Kew, James N C; Dawson, Lee A; Gotti, Cecilia; Moretti, Milena; Shoaib, Mohammed; Wonnacott, Susan

    2009-02-01

    Nicotine enhances attentional and working memory aspects of executive function in the prefrontal cortex (PFC) where dopamine plays a major role. Here, we have determined the nicotinic acetylcholine receptor (nAChR) subtypes that can modulate dopamine release in rat PFC using subtype-selective drugs. Nicotine and 5-Iodo-A-85380 (beta2* selective) elicited [(3)H]dopamine release from both PFC and striatal prisms in vitro and dopamine overflow from medial PFC in vivo. Blockade by dihydro-beta-erythroidine supports the participation of beta2* nAChRs. However, insensitivity of nicotine-evoked [(3)H]dopamine release to alpha-conotoxin-MII in PFC prisms suggests no involvement of alpha6beta2* nAChRs, in contrast to the striatum, and this distinction is supported by immunoprecipitation of nAChR subunits from these tissues. The alpha7 nAChR-selective agonists choline and Compound A also promoted dopamine release from PFC in vitro and in vivo, and their effects were enhanced by the alpha7 nAChR-selective allosteric potentiator PNU-120596 and blocked by specific antagonists. DNQX and MK801 inhibited [(3)H]dopamine release evoked by choline and PNU-120596, suggesting crosstalk between alpha7 nAChRs, glutamate and dopamine in the PFC. In vivo, systemic (but not local) administration of PNU-120596, in the absence of agonist, facilitated dopamine overflow in the medial PFC, consistent with the activation of extracortical alpha7 nAChRs by endogenous acetylcholine or choline. These data establish that both beta2* and alpha7 nAChRs can modulate dopamine release in the PFC in vitro and in vivo. Through their distinct actions on dopamine release, these nAChR subtypes could contribute to executive function, making them specific therapeutic targets for conditions such as schizophrenia and attention deficit hyperactivity disorder.

  19. Investigation of the Pygmy Dipole Resonance in (alpha, alpha 'gamma) coincidence experiments

    Savran, D.; Babilon, M.; van den Berg, A. M.; Harakeh, M. N.; Hasper, J.; Wortche, H. J.; Zilges, A.

    2007-01-01

    We report on first results from experiments using the (alpha, alpha'gamma) reaction at E alpha = 136 MeV to investigate bound electric dipole (El) excitations building the so-called Pygmy Dipole Resonance (PDR) in the semi-magic nucleus Ce-140. The method of (alpha, alpha'gamma) allows the

  20. NMDA receptor dependent PGC-1alpha up-regulation protects the cortical neuron against oxygen-glucose deprivation/reperfusion injury.

    Luo, Yun; Zhu, Wenjing; Jia, Jia; Zhang, Chenyu; Xu, Yun

    2009-09-01

    The peroxisome proliferator activated receptor coactivator 1 alpha (PGC-1alpha) is a nuclear transcriptional coactivator that is widely expressed in the brain areas. Over-expression of PGC-1alpha can protect neuronal cells from oxidant-induced injury. The purpose of the current study is to investigate the role of PGC-1alpha in the oxygen (anoxia) deprivation (OGD) neurons. The PGC-1alpha mRNA and protein level between control and OGD neurons were examined by real-time PCR and Western blot. More PGC-1alpha expression was found in the OGD neurons compared with the normal group. Over-expression of PGC-1alpha suppressed cell apoptosis while inhibition of the PGC-1alpha expression induced cell apoptosis in OGD neurons. Furthermore, increase of PGC-1alpha resulted in activation of N-methyl-D-aspartate (NMDA) receptor, p38, and ERK mitogen-activated protein kinase (MAPK) pathway. The blocking of the NMDA receptor by its antagonists MK-801 reduced PGC-1alpha mRNA expression in OGD neurons, while NMDA itself can directly induce the expression of PGC-1alpha in neuronal cells. At the same time, PD98059 (ERK MAPK inhibitor) and SB203580 (P38 MAPK inhibitor) also prevented the up-regulation of PGC-1alpha in OGD neurons and MK801 can inhibit the expression of P38 and ERK MAPK. These data suggested that the expression of PGC-1alpha was up-regulated in OGD mice cortical neurons, which protected the neurons against OGD injury. Moreover, this effect was correlated to the NMDA receptor and the ERK and P38 MAPK pathway. The protective effect of PGC-1alpha on OGD cortical neurons may be useful for stroke therapy.

  1. Workshop on Precision Measurements of $\\alpha_s$

    Bethke, Siegfried; /Munich, Max Planck Inst.; Hoang, Andre H.; /Vienna U.; Kluth, Stefan; /Munich, Max Planck Inst.; Schieck, Jochen; /Munich U.; Stewart, Iain W.; Aoki, S.; Beneke, M.; Bethke, S.; Blumlein, J.; Brambilla, N.; Brodsky, S.; /MIT, LNS

    2011-10-01

    These are the proceedings of the Workshop on Precision Measurements of {alpha}{sub s} held at the Max-Planck-Institute for Physics, Munich, February 9-11, 2011. The workshop explored in depth the determination of {alpha}{sub s}(m{sub Z}) in the {ovr MS} scheme from the key categories where high precision measurements are currently being made, including DIS and global PDF fits, {tau}-decays, electro-weak precision observables and Z-decays, event-shapes, and lattice QCD. These proceedings contain a short summary contribution from the speakers, as well as the lists of authors, conveners, participants, and talks.

  2. Early Illustrations of Geste Antagoniste in Cervical and Generalized Dystonia

    Broussolle, Emmanuel; Laurencin, Chloé; Bernard, Emilien; Thobois, Stéphane; Danaila, Teodor; Krack, Paul

    2015-01-01

    Background Geste antagoniste, or sensory trick, is a voluntary maneuver that temporarily reduces the severity of dystonic postures or movements. We present a historical review of early reports and illustrations of geste antagoniste. Results In 1894, Brissaud described this phenomenon in Paris in patients with torticollis. He noted that a violent muscular contraction could be reversed by a minor voluntary action. He considered the improvement obtained by what he called “simple mannerisms, childish behaviour or fake pathological movements” was proof of the psychogenic origin of what he named mental torticollis. This concept was supported by photographical illustrations of the patients. The term geste antagoniste was used by Brissaud’s pupils, Meige and Feindel, in their 1902 monograph on movement disorders. Other reports and illustrations of this sign were published in Europe between 1894 and 1906. Although not mentioned explicitly, geste antagoniste was also illustrated in a case report of generalized dystonia in Oppenheim’s 1911 seminal description of dystonia musculorum deformans in Berlin. Discussion Brissaud-Meige’s misinterpretation of the geste antagoniste unfortunately anchored the psychogenic origin of dystonia for decades. In New York, Herz brought dystonia back into the realm of organic neurology in 1944. Thereafter, it was given prominence by other authors, notably Fahn and Marsden in the 1970–1980s. Nowadays, neurologists routinely investigate for geste antagoniste when a dystonic syndrome is suspected, because it provides a further argument in favor of dystonia. The term alleviating maneuver was proposed in 2014 to replace sensory trick or geste antagoniste. This major sign is now part of the motor phenomenology of the 2013 Movement Disorder Society’s classification of dystonia. PMID:26417535

  3. Molecular basis for nondeletion alpha-thalassemia in American blacks. Alpha 2(116GAG----UAG).

    Liebhaber, S A; Coleman, M B; Adams, J G; Cash, F E; Steinberg, M H

    1987-01-01

    An American black woman was found to have the phenotype of moderately severe alpha-thalassemia normally associated with the loss of two to three alpha-globin genes despite an alpha-globin gene map that demonstrated the loss of only a single alpha-globin gene (-alpha/alpha alpha). Several individuals in her kindred with normal alpha-globin gene mapping studies (alpha alpha/alpha alpha) had mild alpha-thalassemia hematologic values consistent with the loss of one to two alpha-globin genes. Thes...

  4. Differentiation of the mRNA transcripts originating from the alpha 1- and alpha 2-globin loci in normals and alpha-thalassemics.

    Liebhaber, S A; Kan, Y W

    1981-01-01

    The alpha-globin polypeptide is encoded by two adjacent genes, alpha 1 and alpha 2. In the normal diploid state (alpha alpha/alpha alpha) all four alpha-globin genes are expressed. Loss or dysfunction of one or more of these genes leads to deficient alpha-globin production and results in alpha-thalassemia. We present a technique to differentially assess the steady-state levels of the alpha 1- and alpha-2-globin messenger RNA (mRNA) transcripts and thus delineate the relative level of expressi...

  5. In vitro pharmacological characterization of a novel selective alpha7 neuronal nicotinic acetylcholine receptor agonist ABT-107.

    Malysz, John; Anderson, David J; Grønlien, Jens H; Ji, Jianguo; Bunnelle, William H; Håkerud, Monika; Thorin-Hagene, Kirten; Ween, Hilde; Helfrich, Rosalind; Hu, Min; Gubbins, Earl; Gopalakrishnan, Sujatha; Puttfarcken, Pamela S; Briggs, Clark A; Li, Jinhe; Meyer, Michael D; Dyhring, Tino; Ahring, Philip K; Nielsen, Elsebet Ø; Peters, Dan; Timmermann, Daniel B; Gopalakrishnan, Murali

    2010-09-01

    Enhancement of alpha7 nicotinic acetylcholine receptor (nAChR) activity is considered a therapeutic approach for ameliorating cognitive deficits present in Alzheimer's disease and schizophrenia. In this study, we describe the in vitro profile of a novel selective alpha7 nAChR agonist, 5-(6-[(3R)-1-azabicyclo[2,2,2]oct-3-yloxy]pyridazin-3-yl)-1H-indole (ABT-107). ABT-107 displayed high affinity binding to alpha7 nAChRs [rat or human cortex, [(3)H](1S,4S)-2,2-dimethyl-5-(6-phenylpyridazin-3-yl)-5-aza-2-azoniabicyclo[2.2.1]heptane (A-585539), K(i) = 0.2-0.6 nM or [(3)H]methyllycaconitine (MLA), 7 nM] that was at least 100-fold selective versus non-alpha7 nAChRs and other receptors. Functionally, ABT-107 did not evoke detectible currents in Xenopus oocytes expressing human or nonhuman alpha3beta4, chimeric (alpha6/alpha3)beta4, or 5-HT(3A) receptors, and weak or negligible Ca(2+) responses in human neuroblastoma IMR-32 cells (alpha3* function) and human alpha4beta2 and alpha4beta4 nAChRs expressed in human embryonic kidney 293 cells. ABT-107 potently evoked human and rat alpha7 nAChR current responses in oocytes (EC(50), 50-90 nM total charge, approximately 80% normalized to acetylcholine) that were enhanced by the positive allosteric modulator (PAM) 4-[5-(4-chloro-phenyl)-2-methyl-3-propionyl-pyrrol-1-yl]-benzenesulfonamide (A-867744). In rat hippocampus, ABT-107 alone evoked alpha7-like currents, which were inhibited by the alpha7 antagonist MLA. In dentate gyrus granule cells, ABT-107 enhanced spontaneous inhibitory postsynaptic current activity when coapplied with A-867744. In the presence of an alpha7 PAM [A-867744 or N-[(3R)-1-azabicyclo[2.2.2]oct-3-yl]-4-chlorobenzamide hydrochloride (PNU-120596)], the addition of ABT-107 elicited MLA-sensitive alpha7 nAChR-mediated Ca(2+) signals in IMR-32 cells and rat cortical cultures and enhanced extracellular signal-regulated kinase phosphorylation in differentiated PC-12 cells. ABT-107 was also effective in protecting rat

  6. Role of golimumab, a TNF-alpha inhibitor, in the treatment of the psoriatic arthritis

    Melissa A Michelon

    2010-05-01

    Full Text Available Melissa A Michelon1, Alice B Gottlieb1,21Tufts University School of Medicine, 2Department of Dermatology, Tufts Medical Center, Boston, MA, USAAbstract: Psoriatic arthritis (PsA is an inflammatory arthritis that affects many psoriasis patients and can often have a debilitating disease progression. Golimumab is a new tumor necrosis factor (TNF antagonist recently approved by the FDA for controlling signs and symptoms of psoriatic arthritis. In a Phase III clinical trial in patients with PsA, patients receiving golimumab showed significant improvement in the signs and symptoms of disease. It was usually well tolerated, but adverse events generally occurred more in patients receiving golimumab compared to placebo. Golimumab has also recently shown efficacy in slowing structural damage in PsA. This new biologic therapy provides physicians with another option in the treatment of this inflammatory arthritis while offering patients certain advantages over other TNF antagonists.Keywords: golimumab, psoriatic arthritis, TNF-alpha inhibitor

  7. α(1)-adrenoceptor blocker naftopidil improves sleep disturbance with reduction in nocturnal urine volume.

    Yokoyama, Osamu; Aoki, Yoshitaka; Tsujimura, Akira; Takao, Tetsuya; Namiki, Mikio; Okuyama, Akihiko

    2011-04-01

    To examine the mechanism underlying improvements in nocturia by α(1)-blockers, we investigated whether the α(1)-blocker naftopidil acts on nocturia with sleep disturbance using a frequency/volume chart (FVC). A total of 56 male patients with lower urinary tract symptoms were enrolled. The inclusion criteria were as follows: eight or more points on the I-PSS; three or more points on the I-PSS score for nocturia; and prostate volume larger than 20 ml. Patients received 50 mg of naftopidil once daily for 4 weeks, and non-responders received 75 mg for another 4 weeks. All patients were examined, and their data entered into FVC for 2 days before and after administration of naftopidil. Quality of sleep was also evaluated using modified Pittsburgh sleep quality index (PSQI). Patients with sleep quality scores of three or four were assigned to sleep disturbance group (n = 33), while those with scores of less than three were assigned to non-disturbance group (n = 23). After administration of naftopidil, total I-PSS decreased and nocturia score decreased from 3.5 to 2.6 (P < 0.01). Total mean score of modified PSQI in sleep disturbance group became significantly lower after administration of naftopidil (from 16.9 to 14.0; P < 0.01). Naftopidil significantly decreased nocturnal urine volume, resulting in a decrease in the nocturnal polyuria index in both sleep disturbance and non-disturbance groups. These results suggest that α(1)-blockers have the ability to normalize sleep disorders. Naftopidil improved nocturnal polyuria regardless of the presence of sleep disturbance, meaning that it might directly reduce nocturnal urine production.

  8. Space Station alpha joint bearing

    Everman, Michael R.; Jones, P. Alan; Spencer, Porter A.

    1987-01-01

    Perhaps the most critical structural system aboard the Space Station is the Solar Alpha Rotary Joint which helps align the power generation system with the sun. The joint must provide structural support and controlled rotation to the outboard transverse booms as well as power and data transfer across the joint. The Solar Alpha Rotary Joint is composed of two transition sections and an integral, large diameter bearing. Alpha joint bearing design presents a particularly interesting problem because of its large size and need for high reliability, stiffness, and on orbit maintability. The discrete roller bearing developed is a novel refinement to cam follower technology. It offers thermal compensation and ease of on-orbit maintenance that are not found in conventional rolling element bearings. How the bearing design evolved is summarized. Driving requirements are reviewed, alternative concepts assessed, and the selected design is described.

  9. Digital readout alpha survey instrument

    Jacobs, M.E.

    1976-01-01

    A prototype solid-state digital readout alpha particle survey instrument has been designed and constructed. The meter incorporates a Ludlum alpha scintillator as a detector, digital logic circuits for control and timing, and a Digilin counting module with reflective liquid crystal display. The device is used to monitor alpha radiation from a surface. Sample counts are totalized over 10-second intervals and displayed digitally in counts per minute up to 19,999. Tests over source samples with counts to 15,600 cpm have shown the device to be rapid, versatile and accurate. The instrument can be fabricated in one man-week and requires about $835 in material costs. A complete set of drawings is included

  10. Alpha-2 adrenergic stimulation triggers Achilles tenocyte hypercellularity: Comparison between two model systems.

    Backman, L J; Andersson, G; Fong, G; Alfredson, H; Scott, A; Danielson, P

    2013-12-01

    The histopathology of tendons with painful tendinopathy is often tendinosis, a fibrosis-like condition of unclear pathogenesis characterized by tissue changes including hypercellularity. The primary tendon cells (tenocytes) have been shown to express adrenoreceptors (mainly alpha-2A) as well as markers of catecholamine production, particularly in tendinosis. It is known that adrenergic stimulation can induce proliferation in other cells. The present study investigated the effects of an exogenously administered alpha-2 adrenergic agonist in an established in vivo Achilles tendinosis model (rabbit) and also in an in vitro human tendon cell culture model. The catecholamine producing enzyme tyrosine hydroxylase and the alpha-2A-adrenoreceptor (α2A AR) were expressed by tenocytes, and alpha-2 adrenergic stimulation had a proliferative effect on these cells, in both models. The proliferation was inhibited by administration of an α2A AR antagonist, and the in vitro model further showed that the proliferative alpha-2A effect was mediated via a mitogenic cell signaling pathway involving phosphorylation of extracellular-signal-regulated kinases 1 and 2. The results indicate that catecholamines produced by tenocytes in tendinosis might contribute to the proliferative nature of the pathology through stimulation of the α2A AR, pointing to a novel target for future therapies. The study furthermore shows that animal models are not necessarily required for all aspects of this research. © 2013 The Authors. Scand J Med Sci Sports published by John Wiley & Sons Ltd.

  11. Conditioning of alpha bearing wastes

    1991-01-01

    Alpha bearing wastes are generated during the reprocessing of spent fuel, mixed oxide fuel fabrication, decommissioning and other activities. The safe and effective management of these wastes is of particular importance owing to the radiotoxicity and long lived characteristics of certain transuranic (TRU) elements. The management of alpha bearing wastes involves a number of stages which include collection, characterization, segregation, treatment, conditioning, transport, storage and disposal. This report describes the currently available matrices and technologies for the conditioning of alpha wastes and relates them to their compatibility with the other stages of the waste management process. The selection of a specific immobilization process is dependent on the waste treatment state and the subsequent handling, transport, storage and disposal requirements. The overall objectives of immobilization are similar for all waste producers and processors, which are to produce: (a) Waste forms with sufficient mechanical, physical and chemical stability to satisfy all stages of handling, transport and storage (referred to as the short term requirements), and (b) Waste forms which will satisfy disposal requirements and inhibit the release of radionuclides to the biosphere (referred to as the long term requirements). Cement and bitumen processes have already been successfully applied to alpha waste conditioning on the industrial scale in many of the IAEA Member States. Cement systems based on BFS and pozzolanic cements have emerged as the principal encapsulation matrices for the full range of alpha bearing wastes. Alternative technologies, such as polymers and ceramics, are being developed for specific waste streams but are unlikely to meet widespread application owing to cost and process complexity. The merits of alpha waste conditioning are improved performance in transport, storage and disposal combined with enhanced public perception of waste management operations. These

  12. Contribution to the study of alpha-alpha interaction; Contribution a l'etude de l'interaction alpha - alpha

    Darriulai, P [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1965-03-01

    Two sets of measurements of the {alpha}-{alpha} elastic scattering differential cross section are presented. The first set - angular distributions from 50 up to 120 MeV - shows two new resonances, 6{sup +} and 8{sup +}, at 25 and 57 MeV. Complex phase shifts are extracted from the data and a phenomenological potential is given. A description of the 3 {alpha}-particle 0{sup +} states in C{sup 12} is made with this interaction potential. The second set - excitation curves between 20 and 50 MeV - allows investigation of the Be{sup 8} level structure within this energy range - It identifies the 16.6 and 16.9 MeV states as 2{sup +}, but the rise of inelastic processes at higher energies makes further identification of spins and parities more and more difficult. (author) [French] Deux series de mesures de la section efficace differentielle de diffusion {alpha}-{alpha} sont presentees. La premiere - distributions angulaires entre 50 et 120 MeV - fait apparaitre deux nouvelles resonances, 6{sup +} et 8{sup +}, a 25 et 57 MeV d'excitation. Des dephasages complexes en sont extraits et un potentiel phenomenologique est presente. Une etude des etats 0{sup +} a parentage (3{alpha}) de {sup 12}C est faite a partir de ce potentiel. La seconde - courbes d'excitation s'etendant de 20 a 50 MeV - met en evidence la structure de {sup 8}Be dans cette region. Elle montre que les niveaux a 16,6 et 16,9 MeV sont des 2{sup +} mais l'importance des processus inelastiques rend difficile l'identification des niveaux d'excitation plus elevee. (auteur)

  13. MDM2 Antagonists Counteract Drug-Induced DNA Damage

    Anna E. Vilgelm

    2017-10-01

    Full Text Available Antagonists of MDM2-p53 interaction are emerging anti-cancer drugs utilized in clinical trials for malignancies that rarely mutate p53, including melanoma. We discovered that MDM2-p53 antagonists protect DNA from drug-induced damage in melanoma cells and patient-derived xenografts. Among the tested DNA damaging drugs were various inhibitors of Aurora and Polo-like mitotic kinases, as well as traditional chemotherapy. Mitotic kinase inhibition causes mitotic slippage, DNA re-replication, and polyploidy. Here we show that re-replication of the polyploid genome generates replicative stress which leads to DNA damage. MDM2-p53 antagonists relieve replicative stress via the p53-dependent activation of p21 which inhibits DNA replication. Loss of p21 promoted drug-induced DNA damage in melanoma cells and enhanced anti-tumor activity of therapy combining MDM2 antagonist with mitotic kinase inhibitor in mice. In summary, MDM2 antagonists may reduce DNA damaging effects of anti-cancer drugs if they are administered together, while targeting p21 can improve the efficacy of such combinations.

  14. Gonadotrophin releasing hormone antagonist in IVF/ICSI

    M S Kamath

    2008-01-01

    Full Text Available Objective : To study the efficacy of gonadotrophin releasing hormone (GnRH antagonist in In-vitro-fertilization/Intracytoplasmic sperm injection (IVF/ICSI cycles. Type of Study : Observational study. Setting: Reproductive Medicine Unit, Christian Medical College Hospital, Vellore, Tamil Nadu. Materials and Methods: GnRH antagonists were introduced into our practice in November 2005. Fifty-two women undergoing the antagonist protocol were studied and information gathered regarding patient profile, treatment parameters (total gonadotrophin dosage, duration of treatment, and oocyte yield, and outcomes in terms of embryological parameters (cleavage rates, implantation rates and clinical pregnancy. These parameters were compared with 121 women undergoing the standard long protocol. The costs between the two groups were also compared. Main Outcome : Clinical pregnancy rate. Results : The clinical pregnancy rate per embryo transfer in the antagonist group was 31.7% which was comparable to the clinical pregnancy rate in women undergoing the standard long protocol (30.63%. The costs between the two groups were comparable. Conclusions : GnRH antagonist protocol was found to be effective and comparable to the standard long protocol regimen. In addition it was simple, convenient, and patient friendly.

  15. Test chamber for alpha spectrometry

    Larsen, Robert P.

    1977-01-01

    Alpha emitters for low-level radiochemical analysis by measurement of alpha spectra are positioned precisely with respect to the location of a surface-barrier detector by means of a chamber having a removable threaded planchet holder. A pedestal on the planchet holder holds a specimen in fixed engagement close to the detector. Insertion of the planchet holder establishes an O-ring seal that permits the chamber to be pumped to a desired vacuum. The detector is protected against accidental contact and resulting damage.

  16. Clebopride enhances contractility of the guinea pig stomach by blocking peripheral D2 dopamine receptor and alpha-2 adrenoceptor.

    Takeda, K; Taniyama, K; Kuno, T; Sano, I; Ishikawa, T; Ohmura, I; Tanaka, C

    1991-05-01

    The mechanism of action of clebopride on the motility of guinea pig stomach was examined by the receptor binding assay for bovine brain membrane and by measuring gastric contractility and the release of acetylcholine from the stomach. The receptor binding assay revealed that clebopride bound to the D2 dopamine receptor with a high affinity and to the alpha-2 adrenoceptor and 5-HT2 serotonin receptor with relatively lower affinity, and not to D1 dopamine, alpha-1 adrenergic, muscarinic acetylcholine, H1 histamine, or opioid receptor. In strips of the stomach, clebopride at 10(-8) M to 10(-5) M enhanced the electrical transmural stimulation-evoked contraction and the release of acetylcholine. This enhancement was attributed to the blockade of the D2 dopamine receptor and alpha-2 adrenoceptor because: 1) Maximum responses obtained with specific D2 dopamine receptor antagonist, domperidone, and with specific alpha-2 adrenoceptor antagonist, yohimbine, were smaller than that with clebopride, and the sum of the effects of these two specific receptor antagonists is approximately equal to the effect of clebopride. 2) The facilitatory effect of clebopride was partially eliminated by pretreatment of the sample with domperidone or yohimbine, and the facilitatory effect of clebopride was not observed in preparations treated with the combination of domperidone and yohimbine. Clebopride also antagonized the inhibitory effects of dopamine and clonidine on the electrical transmural stimulation-evoked responses. These results indicate that clebopride acts on post ganglionic cholinergic neurons at D2 and alpha-2 receptors in this preparation to enhance enteric nervous system stimulated motility.

  17. Clebopride enhances contractility of the guinea pig stomach by blocking peripheral D2 dopamine receptor and alpha-2 adrenoceptor

    Takeda, K.; Taniyama, K.; Kuno, T.; Sano, I.; Ishikawa, T.; Ohmura, I.; Tanaka, C.

    1991-01-01

    The mechanism of action of clebopride on the motility of guinea pig stomach was examined by the receptor binding assay for bovine brain membrane and by measuring gastric contractility and the release of acetylcholine from the stomach. The receptor binding assay revealed that clebopride bound to the D2 dopamine receptor with a high affinity and to the alpha-2 adrenoceptor and 5-HT2 serotonin receptor with relatively lower affinity, and not to D1 dopamine, alpha-1 adrenergic, muscarinic acetylcholine, H1 histamine, or opioid receptor. In strips of the stomach, clebopride at 10 - 8 M to 10 - 5 M enhanced the electrical transmural stimulation-evoked contraction and the release of acetylcholine. This enhancement was attributed to the blockade of the D2 dopamine receptor and alpha-2 adrenoceptor because: (1) Maximum responses obtained with specific D2 dopamine receptor antagonist, domperidone, and with specific alpha-2 adrenoceptor antagonist, yohimbine, were smaller than that with clebopride, and the sum of the effects of these two specific receptor antagonists is approximately equal to the effect of clebopride. (2) The facilitatory effect of clebopride was partially eliminated by pretreatment of the sample with domperidone or yohimbine, and the facilitatory effect of clebopride was not observed in preparations treated with the combination of domperidone and yohimbine. Clebopride also antagonized the inhibitory effects of dopamine and clonidine on the electrical transmural stimulation-evoked responses. These results indicate that clebopride acts on post ganglionic cholinergic neurons at D2 and alpha-2 receptors in this preparation to enhance enteric nervous system stimulated motility

  18. Effects of catecholamine agonists and antagonists on alcohol uptake in rats with different stages of experimental alcoholism

    Burov, Yu V; Varov, A I

    1985-02-01

    The effects of various catecholamine agonists and antagonists on 15% ethanol ingestion by outbred albino rats were studied in relation to the stage of experimental alcoholism. In animals with stage I and II alcoholism, alcohol intake was most profoundly inhibited by administration of alpha-adrenoblockers (AA), klofelin, and alpha-methyl-DOPA (AMD), while L-DOPA and cocaine stimulated a significant increase in ethanol ingestion. In stage III alcoholism, both AA and L-DOPA depressed alcohol intake, while AMD and haloperidol had a stimulatory effect. It appears, therefore, that different neurochemical mechanisms are involved in alcohol dependence in different stages of experimental alcoholism in the rat. Furthermore, it seems evident that alpha-adrenergic receptors have a key function in maintaining alcohol dependence. In well-established physical dependence, the importance of the noradrenergic system seems to diminish and dopaminergic mechanisms appear to become predominant. Consequently, in the initial stages of alcoholism, agents which depress the noradrenergic system seem indicated, while at the stage of physical dependence agents which normalize noradrenergic mechanisms and depress dopaminergic mechanisms should be considered. 13 references.

  19. Isometric and isokinetic hip strength and agonist/antagonist ratios in symptomatic femoroacetabular impingement.

    Diamond, Laura E; Wrigley, Tim V; Hinman, Rana S; Hodges, Paul W; O'Donnell, John; Takla, Amir; Bennell, Kim L

    2016-09-01

    This study investigated isometric and isokinetic hip strength in individuals with and without symptomatic femoroacetabular impingement (FAI). The specific aims were to: (i) determine whether differences exist in isometric and isokinetic hip strength measures between groups; (ii) compare hip strength agonist/antagonist ratios between groups; and (iii) examine relationships between hip strength and self-reported measures of either hip pain or function in those with FAI. Cross-sectional. Fifteen individuals (11 males; 25±5 years) with symptomatic FAI (clinical examination and imaging (alpha angle >55° (cam FAI), and lateral centre edge angle >39° and/or positive crossover sign (combined FAI))) and 14 age- and sex-matched disease-free controls (no morphological FAI on magnetic resonance imaging) underwent strength testing. Maximal voluntary isometric contraction strength of hip muscle groups and isokinetic hip internal (IR) and external rotation (ER) strength (20°/s) were measured. Groups were compared with independent t-tests and Mann-Whitney U tests. Participants with FAI had 20% lower isometric abduction strength than controls (p=0.04). There were no significant differences in isometric strength for other muscle groups or peak isokinetic ER or IR strength. The ratio of isometric, but not isokinetic, ER/IR strength was significantly higher in the FAI group (p=0.01). There were no differences in ratios for other muscle groups. Angle of peak IR torque was the only feature correlated with symptoms. Individuals with symptomatic FAI demonstrate isometric hip abductor muscle weakness and strength imbalance in the hip rotators. Strength measurement, including agonist/antagonist ratios, may be relevant for clinical management of FAI. Copyright © 2015 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  20. First Irish birth following IVF therapy using antagonist protocol.

    Mocanu, E V

    2012-02-01

    BACKGROUND: During in vitro fertilization (IVF), the prevention of a premature LH surge was traditionally achieved using a gonadotrophin releasing hormone agonist (GnRH-a), and more recently, a GnRH antagonist. AIMS: We report a case of a 37 year old treated using the GnRH antagonist in a second completed cycle of IVF. METHODS: IVF was performed for primary infertility of 5-year duration due to frozen pelvis secondary to endometriosis. RESULTS: Following controlled ovarian hyperstimulation, oocyte recovery and fertilization, cleavage and transfer of two zygotes, a pregnancy established. A twin gestation was diagnosed at 7-weeks scan and pregnancy ended with the delivery of twin girls by emergency caesarean section. CONCLUSION: This is a first report of a delivery following IVF using the antagonist protocol in Ireland. Such therapy is patient friendly and its use should be introduced on a larger scale in clinical practice.

  1. ANTAGONISTIC BACTERIA AGAINST SCHIZOPHYLLUM COMMUNE FR. IN PENINSULAR MALAYSIA

    ANTARJO DIKIN

    2006-01-01

    Full Text Available Schizophyllum commune Fr., is one of the important fungi, causes brown germ and seed rot of oil palm. Biodiversity of antagonistic bacteria from oil palm plantations in Peninsular Malaysia is expected to support in development of biopesticide. Isolation with liquid assay and screening antagonistic bacteria using dual culture assay were carried out in the bioexploration. A total of 265 bacterial isolates from plant parts of oil palm screened 52 antagonistic bacterial isolates against 5. commune. Bacterial isolates were identified by using Biolog* Identification System i.e. Bacillus macroccanus, B. thermoglucosidasius, Burkholderia cepacia, B. gladioli, B. multivorans, B pyrrocinia, B. spinosa, Corynebacterium agropyri, C. misitidis, Enterobacter aerogenes, Microbacterium testaceum, Pseudomonas aeruginosa, P. citronellolis, Rhodococcus rhodochrous, Serratia ficaria, Serratia sp., S. marcescens, Staphylococcus sciuri, Sternotrophomonas maltophilia.

  2. Alpha 2-adrenergic receptor stimulation of phospholipase A2 and of adenylate cyclase in transfected Chinese hamster ovary cells is mediated by different mechanisms

    Jones, S.B.; Halenda, S.P.; Bylund, D.B.

    1991-01-01

    The effect of alpha 2-adrenergic receptor activation on adenylate cyclase activity in Chinese hamster ovary cells stably transfected with the alpha 2A-adrenergic receptor gene is biphasic. At lower concentrations of epinephrine forskolin-stimulated cyclic AMP production is inhibited, but at higher concentrations the inhibition is reversed. Both of these effects are blocked by the alpha 2 antagonist yohimbine but not by the alpha 1 antagonist prazosin. Pretreatment with pertussis toxin attenuates inhibition at lower concentrations of epinephrine and greatly potentiates forskolin-stimulated cyclic AMP production at higher concentrations of epinephrine. alpha 2-Adrenergic receptor stimulation also causes arachidonic acid mobilization, presumably via phospholipase A2. This effect is blocked by yohimbine, quinacrine, removal of extracellular Ca2+, and pretreatment with pertussis toxin. Quinacrine and removal of extracellular Ca2+, in contrast, have no effect on the enhanced forskolin-stimulated cyclic AMP production. Thus, it appears that the alpha 2-adrenergic receptor in these cells can simultaneously activate distinct signal transduction systems; inhibition of adenylate cyclase and stimulation of phospholipase A2, both via G1, and potentiation of cyclic AMP production by a different (pertussis toxin-insensitive) mechanism

  3. Alpha 2-adrenergic receptor stimulation of phospholipase A2 and of adenylate cyclase in transfected Chinese hamster ovary cells is mediated by different mechanisms

    Jones, S.B.; Halenda, S.P.; Bylund, D.B. (Univ. of Missouri-Columbia (USA))

    1991-02-01

    The effect of alpha 2-adrenergic receptor activation on adenylate cyclase activity in Chinese hamster ovary cells stably transfected with the alpha 2A-adrenergic receptor gene is biphasic. At lower concentrations of epinephrine forskolin-stimulated cyclic AMP production is inhibited, but at higher concentrations the inhibition is reversed. Both of these effects are blocked by the alpha 2 antagonist yohimbine but not by the alpha 1 antagonist prazosin. Pretreatment with pertussis toxin attenuates inhibition at lower concentrations of epinephrine and greatly potentiates forskolin-stimulated cyclic AMP production at higher concentrations of epinephrine. alpha 2-Adrenergic receptor stimulation also causes arachidonic acid mobilization, presumably via phospholipase A2. This effect is blocked by yohimbine, quinacrine, removal of extracellular Ca2+, and pretreatment with pertussis toxin. Quinacrine and removal of extracellular Ca2+, in contrast, have no effect on the enhanced forskolin-stimulated cyclic AMP production. Thus, it appears that the alpha 2-adrenergic receptor in these cells can simultaneously activate distinct signal transduction systems; inhibition of adenylate cyclase and stimulation of phospholipase A2, both via G1, and potentiation of cyclic AMP production by a different (pertussis toxin-insensitive) mechanism.

  4. Decreased agonist sensitivity of human GABA(A) receptors by an amino acid variant, isoleucine to valine, in the alpha1 subunit.

    Westh-Hansen, S E; Rasmussen, P B; Hastrup, S; Nabekura, J; Noguchi, K; Akaike, N; Witt, M R; Nielsen, M

    1997-06-25

    Recombinant human GABA(A) receptors were investigated in vitro by coexpression of cDNAs coding for alpha1, beta2, and gamma2 subunits in the baculovirus/Sf-9 insect cell system. We report that a single amino acid exchange (isoleucine 121 to valine 121) in the N-terminal, extracellular part of the alpha1 subunit induces a marked decrease in agonist GABA(A) receptor ligand sensitivity. The potency of muscimol and GABA to inhibit the binding of the GABA(A) receptor antagonist [3H]SR 95531 (2-(3-carboxypropyl)-3-amino-6-(4-methoxyphenyl)pyridazinium bromide) was higher in receptor complexes of alpha1(ile 121) beta2gamma2 than in those of alpha1(val 121) beta2gamma2 (IC50 values were 32-fold and 26-fold lower for muscimol and GABA, respectively). The apparent affinity of the GABA(A) receptor antagonist bicuculline methiodide to inhibit the binding of [3H]SR 95531 did not differ between the two receptor complex variants. Electrophysiological measurements of GABA induced whole-cell Cl- currents showed a ten-fold decrease in the GABA(A) receptor sensitivity of alpha1 (val 121) beta2gamma2 as compared to alpha1(ile 121) beta2gamma2 receptor complexes. Thus, a relatively small change in the primary structure of the alpha1 subunit leads to a decrease selective for GABA(A) receptor sensitivity to agonist ligands, since no changes were observed in a GABA(A) receptor antagonist affinity and benzodiazepine receptor binding.

  5. Endothelin receptor antagonists influence cardiovascular morphology in uremic rats.

    Nabokov, A V; Amann, K; Wessels, S; Münter, K; Wagner, J; Ritz, E

    1999-02-01

    In is generally held that renal failure results in blood pressure (BP)-independent structural changes of the myocardium and the vasculature. The contribution, if any, of endothelin (ET) to these changes has been unknown. We morphometrically studied random samples of the left ventricle myocardium and small intramyocardial arteries in subtotally (5/6) nephrectomized (SNx) male Sprague-Dawley rats treated with either the selective ETA receptor antagonist BMS182874 (30 mg/kg/day) or the nonselective ETA/ETB receptor antagonist Ro46-2005 (30 mg/kg/day) in comparison with either sham-operated rats, untreated SNx, or SNx rats treated with the angiotensin-converting enzyme inhibitor trandolapril (0.1 mg/kg/day). Eight weeks later, systolic BP was lower in trandolapril-treated SNx compared with untreated SNx animals. No decrease in BP was seen following either ET receptor antagonist at the dose used. A significantly increased volume density of the myocardial interstitium was found in untreated SNx rats as compared with sham-operated controls. Such interstitial expansion was prevented by trandolapril and either ET receptor antagonist. SNx caused a substantial increase in the wall thickness of small intramyocardial arteries. The increase was prevented by trandolapril or BMS182874 treatment. The arteriolar wall:lumen ratio was significantly lower in all treated groups when compared with untreated SNx. In contrast, only trandolapril, but not the ET receptor antagonists, attenuated thickening of the aortic media in SNx animals. The ETA-selective and ETA/ETB-nonselective receptor antagonists appear to prevent development of myocardial fibrosis and structural changes of small intramyocardial arteries in experimental chronic renal failure. This effect is independent of systemic BP.

  6. Source preparation in alpha spectrometry

    Lally, A E [UKAEA Atomic Energy Research Establishment, Harwell. Environmental and Medical Sciences Div.; Glover, K M [UKAEA Atomic Energy Research Establishment, Harwell. Chemistry Div.

    1984-06-15

    Techniques, for the preparation of sources suitable for alpha spectrometric measurements are presented. These include vacuum sublimation, electrodeposition, self-deposition, direct evaporation, direct precipitation and the use of solvents and spreading agents. The relative merits of each technique and the applicability to both high and low levels of activity are considered.

  7. Labetalol, a new alpha- and beta-adrenoreceptor blocking agent, in hypertension.

    Hansson, L; Hänel, B

    1976-08-01

    1Labetalol is a new compound with antagonistic effects at both alpha- and beta-adrenoreceptor sites. 2 When given to 12 hypertensive patients at an average daily dosage of 273 mg for 7 months statistically significant reductions (compared with pretreatment values) in recumbent and standing blood pressure were observed. 3 Treatment has to be withdrawn in one patient because of vivid dreams, and dosage was reduced in one patient because of dizziness. Otherwise no side-effects of importance were noted. 4 It can therefore be concluded that labetalol offers a useful anti-hypertensive effect and that this compound is well tolerated.

  8. Discovery of tertiary sulfonamides as potent liver X receptor antagonists.

    Zuercher, William J; Buckholz, Richard G; Campobasso, Nino; Collins, Jon L; Galardi, Cristin M; Gampe, Robert T; Hyatt, Stephen M; Merrihew, Susan L; Moore, John T; Oplinger, Jeffrey A; Reid, Paul R; Spearing, Paul K; Stanley, Thomas B; Stewart, Eugene L; Willson, Timothy M

    2010-04-22

    Tertiary sulfonamides were identified in a HTS as dual liver X receptor (LXR, NR1H2, and NR1H3) ligands, and the binding affinity of the series was increased through iterative analogue synthesis. A ligand-bound cocrystal structure was determined which elucidated key interactions for high binding affinity. Further characterization of the tertiary sulfonamide series led to the identification of high affinity LXR antagonists. GSK2033 (17) is the first potent cell-active LXR antagonist described to date. 17 may be a useful chemical probe to explore the cell biology of this orphan nuclear receptor.

  9. Hyperglycemia of Diabetic Rats Decreased by a Glucagon Receptor Antagonist

    Johnson, David G.; Ulichny Goebel, Camy; Hruby, Victor J.; Bregman, Marvin D.; Trivedi, Dev

    1982-02-01

    The glucagon analog [l-Nα-trinitrophenylhistidine, 12-homoarginine]-glucagon (THG) was examined for its ability to lower blood glucose concentrations in rats made diabetic with streptozotocin. In vitro, THG is a potent antagonist of glucagon activation of the hepatic adenylate cyclase assay system. Intravenous bolus injections of THG caused rapid decreases (20 to 35 percent) of short duration in blood glucose. Continuous infusion of low concentrations of the inhibitor led to larger sustained decreases in blood glucose (30 to 65 percent). These studies demonstrate that a glucagon receptor antagonist can substantially reduce blood glucose levels in diabetic animals without addition of exogenous insulin.

  10. Calibration of sources for alpha spectroscopy systems

    Freitas, I.S.M.; Goncalez, O.L.

    1992-01-01

    This paper describes the calibration methodology for measuring the total alpha activity of plane and thin sources with the Alpha Spectrometer for Silicon Detector in the Nuclear Measures and Dosimetry laboratory at IEAv/CTA. (author)

  11. VARIAR Study: Assessment of short-term efficacy and safety of rituximab compared to an tumor necrosis factor alpha antagonists as second-line drug therapy in patients with rheumatoid arthritis refractory to a first tumor necrosis factor alpha antagonist.

    Torrente-Segarra, Vicenç; Acosta Pereira, Asunción; Morla, Rosa; Ruiz, José Miguel; Clavaguera, Teresa; Figuls, Ramon; Corominas, Hector; Geli, Carme; Roselló, Rosa; de Agustín, Juan José; Alegre, Cayetano; Pérez, Carolina; García, Angel; Rodríguez de la Serna, Arturo

    to compare the short-term efficacy and safety of rituximab (RTX) therapy versus anti-TNF in rheumatoid arthritis (RA) patients after discontinuation of a first anti-TNF agent. prospective observational multicenter study in the clinical practice setting, involving patients with severe RA refractory to a first anti-TNF agent, who received either RTX or a second anti-TNF (2TNF), comparing the efficacy endpoints, EULAR response (Good/Moderate) and safety at 6 months. 103 patients enrolled, 82 completed 6-month follow-up, 73.7% women. Baseline data for RTX and 2TNF groups, respectively: TJC, 8.6 and 6.6; SJC, 8.8 and 7.5; DAS28 score, 5.45 (±1.28) and 5.18 (±1.21) (p=0.048), ESR, 41 and 38.7mmHg; and HAQ, 1.2 and 1.0. Improvement was observed in all parameters, with no significant differences (except for a more marked reduction in ESR with RTX). There were no serious adverse events. RTX use as second-line therapy after anti-TNF failure led to improvements in the efficacy and functional variables at 6 months, with no serious adverse events. These results were comparable to those observed in patients who used a second anti-TNF agent in the same clinical scenario. Copyright © 2015 Elsevier España, S.L.U. and Sociedad Española de Reumatología y Colegio Mexicano de Reumatología. All rights reserved.

  12. The alpha-cell as target for type 2 diabetes therapy

    Christensen, Mikkel; Bagger, Jonatan I; Vilsboll, Tina

    2011-01-01

    for type 2 diabetes. Several lines of preclinical evidence have paved the way for the development of drugs, which suppress glucagon secretion or antagonize the glucagon receptor. In this review, the physiological actions of glucagon and the role of glucagon in type 2 diabetic pathophysiology are outlined...... antagonists are confronted with several safety issues. At present, available pharmacological agents based on the glucose-dependent glucagonostatic effects of GLP-1 represent the most favorable way to apply constraints to the alpha-cell in type 2 diabetes.......-coupled receptors in the hepatocytes. Type 2 diabetic patients are characterized by elevated glucagon levels contributing decisively to hyperglycemia in these patients. Accumulating evidence demonstrates that targeting the pancreatic alpha-cell and its main secretory product glucagon is a possible treatment...

  13. Evidence that 17alpha-estradiol is biologically active in the uterine tissue: Antiuterotonic and antiuterotrophic action

    Navarrete Erika

    2005-07-01

    Full Text Available Abstract Background 17alpha-Estradiol has been considered as the hormonally inactive isomer of 17beta-estradiol. Recently, nongenomic (smooth muscle relaxation and genomic (light estrogenic activity effects of 17alpha-estradiol have been reported, but no reports have yet determined its possible antiestrogenic activity. Therefore, this study investigated: the nongenomic action of 17alpha-estradiol on uterine contractile activity and its potential agonist-antagonist activity on uterine growth. Methods Uterine rings from rats were isometrically recorded. Different concentrations (0.2–200 microM of 17alpha-estradiol were tested on spontaneous contraction and equimolarly compared with 17beta-estradiol. To examine the mechanism of 17alpha-estradiol action, its effect was studied in presence of beta2-antagonist (propranolol, antiestrogens (tamoxifen and ICI 182,780 or inhibitors of protein synthesis (cycloheximide and transcription (actinomycin D. Moreover, contractions induced by high potassium (KCl solution or calcium in depolarized tissues by KCl-calcium free solution were exposed to 17alpha-estradiol. Collaterally, we performed an uterotrophic assay in adult ovariectomized rats measuring the uterine wet weight. The administration for three days of 0.3 microM/day/Kg 17beta-estradiol was equimolarly compared with the response produced by 17alpha-estradiol. Antiuterotrophic activity was assayed by administration of 0.3 microM/day/Kg 17beta-estradiol and various doses ratios (1:1, 1:3, 1:5, and 1:100 of 17alpha-estradiol. Results The estradiol isomers elicited an immediate relaxation, concentration-dependent and reversible on spontaneous contraction. 17alpha-Estradiol presented lower potency than 17beta-estradiol although it did not antagonize 17beta-estradiol-induced relaxation. Relaxation to 17alpha-estradiol was not inhibited by propranolol, tamoxifen, ICI 182,780, cycloheximide or actinomycin D. The KCl contractions were also sensitive to 17alpha

  14. Training detector as simulator of alpha detector

    Tirosh, D.; Duvniz, E.; Assido, H.; Barak, D.; Paran, J.

    1997-01-01

    Alpha contamination is a common phenomena in radiation research laboratories and other sites. Training staff to properly detect and control alpha contamination, present special problems. In order to train health physics personnel, while using alpha sources, both the trainers and the trainees are inevitably exposed to alpha contamination. This fact of course, comes in conflict with safety principles. In order to overcome these difficulties, a training detector was developed, built and successfully tested. (authors)

  15. Antidepressant-like effects of nicotinic acetylcholine receptor antagonists, but not agonists, in the mouse forced swim and mouse tail suspension tests

    Andreasen T., Jesper; Olsen, G M; Wiborg, O

    2009-01-01

    Current literature suggests involvement of nicotinic acetylcholine receptors (nAChRs) in major depression. However, it is controversial whether the antidepressant-like effect of nAChR modulation is induced by activation, desensitization or inhibition of central nAChRs. In addition, the specific n......AChR subtype/s involved remains unknown. In this study, we systematically compared the effects of non-selective and selective nicotinic agonists and antagonists in two different tests for antidepressant effects in mice: the tail suspension test and the forced swim test. Compounds: nicotine, RJR-2403 (alpha4...

  16. NMDA receptor antagonists for the treatment of neuropathic pain

    Collins, S.; Sigtermans, M.J.; Dahan, A.; Zuurmond, W.W.A.; Perez, R.S.G.M.

    2010-01-01

    Objective. The N-methyl-D-Aspartate (NMDA) receptor has been proposed as a primary target for the treatment of neuropathic pain. The aim of the present study was to perform a meta-analysis evaluating the effects of (individual) NMDA receptor antagonists on neuropathic pain, and the response

  17. Enhanced Chronic Pain Management Utilizing Chemokine Receptor Antagonists

    2016-08-01

    approximately halfway into the solution. All animals were tested at 60, 15 and 0 min before drug injection. For each animal , the first reading was discarded...approval (December 31, 2015), hiring new personnel, conducting baseline testing for procedures not involving animals , testing equipment, developing...treatment; Analgesia; Nociception; Antinociception; Inflammation; Chemokines; Chemokine receptor antagonists; Opioid analgesics; Animal models of pain

  18. Pharmacoepidemiological assessment of drug interactions with vitamin K antagonists

    Pottegård, Anton; Christensen, Rene dePont; Wang, Shirley V

    2014-01-01

    PurposeWe present a database of prescription drugs and international normalized ratio (INR) data and the applied methodology for its use to assess drug-drug interactions with vitamin K antagonists (VKAs). We use the putative interaction between VKAs and tramadol as a case study. MethodsWe used...

  19. Komplikationer til langtidsbehandling med vitamin K-antagonister

    May, O; Garne, E; Mickley, H

    1990-01-01

    Long-term treatment with vitamin K antagonists (vKA) frequently involves complications. The commonest complication is haemorrhage and cases of serious haemorrhage are stated in the literature to occur with a frequency per 1,000 treatment years of 12-108, of which 2-17 are fatal. The majority...

  20. Management of hyperkalaemia consequent to mineralocorticoid-receptor antagonist therapy

    Roscioni, Sara S.; de Zeeuw, Dick; Bakker, Stephan J. L.; Lambers Heerspink, Hiddo J.

    2012-01-01

    Mineralocorticoid-receptor antagonists (MRAs) reduce blood pressure and albuminuria in patients treated with angiotensin-converting-enzyme inhibitors or angiotensin-II-receptor blockers. The use of MRAs, however, is limited by the occurrence of hyperkalaemia, which frequently occurs in patients

  1. Effect of Three Calmodulin Antagonists on Subpopulations of CD44 ...

    Tropical Journal of Pharmaceutical Research is indexed by Science Citation Index (SciSearch), Scopus,. International Pharmaceutical ... cancer stem cells. It is not known, however, whether targeting CD44 can alter the fate of cancer stem cells themselves. In this study, the effect of the calmodulin antagonists (N-(10-.

  2. The Effect of Sympathetic Antagonists on the Antidepressant Action ...

    Alprazolam is an anti-anxiety drug shown to be effective in the treatment of depression. In this study, the effect of sympathetic receptor antagonists on alprazolam–induced antidepressant action was studied using a mouse model of forced swimming behavioral despair. The interaction of three sympathetic receptor ...

  3. The Effect of Antagonist Muscle Sensory Input on Force Regulation.

    Tanya Onushko

    Full Text Available The purpose of this study was to understand how stretch-related sensory feedback from an antagonist muscle affects agonist muscle output at different contraction levels in healthy adults. Ten young (25.3 ± 2.4 years, healthy subjects performed constant isometric knee flexion contractions (agonist at 6 torque levels: 5%, 10%, 15%, 20%, 30%, and 40% of their maximal voluntary contraction. For half of the trials, subjects received patellar tendon taps (antagonist sensory feedback during the contraction. We compared error in targeted knee flexion torque and hamstring muscle activity, with and without patellar tendon tapping, across the 6 torque levels. At lower torque levels (5%, 10%, and 15%, subjects produced greater knee torque error following tendon tapping compared with the same torque levels without tendon tapping. In contrast, we did not find any difference in torque output at higher target levels (20%, 30%, and 40% between trials with and without tendon tapping. We also observed a load-dependent increase in the magnitude of agonist muscle activity after tendon taps, with no associated load-dependent increase in agonist and antagonist co-activation, or reflex inhibition from the antagonist tapping. The findings suggest that at relatively low muscle activity there is a deficiency in the ability to correct motor output after sensory disturbances, and cortical centers (versus sub-cortical are likely involved.

  4. Antagonistic bioactivity of an endophytic bacterium isolated from ...

    Antagonistic bioactivity of an endophytic bacterium isolated from Epimedium brevicornu Maxim. R He, G Wang, X Liu, C Zhang, F Lin. Abstract. Endophytic bacteria are one of the most potential biological control agents in plant disease protection. The aim of this work was to evaluate the antimicrobial activities of a strain of ...

  5. Multiple sclerosis following treatment with a cannabinoid receptor-1 antagonist

    van Oosten, B. W.; Killestein, J.; Mathus-Vliegen, E. M. H.; Polman, C. H.

    2004-01-01

    Laboratory research including animal models of human disease suggests that cannabinoids might have therapeutic potential in multiple sclerosis (MS). We have recently seen a 46-year-old woman who developed MS after starting treatment with a cannabinoid receptor antagonist for obesity. The occurrence

  6. Characterization of a novel non-steroidal glucocorticoid receptor antagonist

    Li, Qun-Yi; Zhang, Meng [The National Center for Drug Screening, Shanghai (China); State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai (China); Hallis, Tina M.; DeRosier, Therese A. [Cell Systems Division, Invitrogen, Madison, WI (United States); Yue, Jian-Min; Ye, Yang [State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai (China); Mais, Dale E. [The National Center for Drug Screening, Shanghai (China); MPI Research, Mattawan, MI (United States); Wang, Ming-Wei, E-mail: wangmw@mail.shcnc.ac.cn [The National Center for Drug Screening, Shanghai (China); State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai (China)

    2010-01-15

    Selective antagonists of the glucocorticoid receptor (GR) are desirable for the treatment of hypercortisolemia associated with Cushing's syndrome, psychic depression, obesity, diabetes, neurodegenerative diseases, and glaucoma. NC3327, a non-steroidal small molecule with potent binding affinity to GR (K{sub i} = 13.2 nM), was identified in a high-throughput screening effort. As a full GR antagonist, NC3327 greatly inhibits the dexamethasone (Dex) induction of marker genes involved in hepatic gluconeogenesis, but has a minimal effect on matrix metalloproteinase 9 (MMP-9), a GR responsive pro-inflammatory gene. Interestingly, the compound recruits neither coactivators nor corepressors to the GR complex but competes with glucocorticoids for the interaction between GR and a coactivator peptide. Moreover, NC3327 does not trigger GR nuclear translocation, but significantly blocks Dex-induced GR transportation to the nucleus, and thus appears to be a 'competitive' GR antagonist. Therefore, the non-steroidal compound, NC3327, may represent a new class of GR antagonists as potential therapeutics for a variety of cortisol-related endocrine disorders.

  7. Manumycin from a new Streptomyces strain shows antagonistic ...

    Manumycin from a new Streptomyces strain shows antagonistic effect against methicillin-resistant Staphylococcus aureus (MRSA)/vancomycin-resistant enterococci (VRE) strains from Korean Hospitals. Yun Hee Choi, Seung Sik Cho, Jaya Ram Simkhada, Chi Nam Seong, Hyo Jeong Lee, Hong Seop Moon, Jin Cheol Yoo ...

  8. Effects of calcium antagonists on hypertension and diastolic function ...

    Calcium antagonists are known to decrease blood pressure acutely and chronically in hypertensive patients with hypertensive heart disease, and also to improve their systolic function. However, disorders of diastolic function may occur early in hypertensive heart disease. The improvement of diastolic function by nifedipine ...

  9. Sympatho-inhibitory properties of various AT1 receptor antagonists

    Balt, Jippe C.; Mathy, Marie-Jeanne; Pfaffendorf, Martin; van Zwieten, Peter A.

    2002-01-01

    It is well known that angiotensin II (Ang II) can facilitate the effects of sympathetic neurotransmission. In the present study, using various experimental models, we investigated the inhibitory effects of several Ang II subtype 1 receptor (AT1) antagonists on this Ang II-induced facilitation. We

  10. Possible site of action of CGRP antagonists in migraine

    Tfelt-Hansen, Peer; Olesen, Jes

    2011-01-01

    The calcitonin gene-related peptide (CGRP) receptor antagonists olcegepant and telcagepant are very potent drugs. Both are effective in migraine but in doses much higher than would be predicted from receptor binding and other in vitro results. This could perhaps suggest an effect of CGRP antagoni...

  11. Christianity and Antagonistic Challenges in Igbo Land of Nigeria: A ...

    Christianity and Antagonistic Challenges in Igbo Land of Nigeria: A Reflection. ... The church mission society (CMS) along side the Royal Niger Company was working ... is to win the confidence of the people by establishing agricultural settlements, ... FAQ's · More about AJOL · AJOL's Partners · Terms and Conditions of Use ...

  12. Possible site of action of CGRP antagonists in migraine

    Tfelt-Hansen, Peer; Olesen, Jes

    2011-01-01

    The calcitonin gene-related peptide (CGRP) receptor antagonists olcegepant and telcagepant are very potent drugs. Both are effective in migraine but in doses much higher than would be predicted from receptor binding and other in vitro results. This could perhaps suggest an effect of CGRP...

  13. Benzodiazepine receptor antagonists for acute and chronic hepatic encephalopathy

    Als-Nielsen, B; Kjaergard, L L; Gluud, C

    2001-01-01

    The pathogenesis of hepatic encephalopathy is unknown. It has been suggested that liver failure leads to the accumulation of substances that bind to a receptor-complex in the brain resulting in neural inhibition which may progress to coma. Several trials have assessed benzodiazepine receptor...... antagonists for hepatic encephalopathy, but the results are conflicting....

  14. Voltage-Gated Calcium Channel Antagonists and Traumatic Brain Injury

    Bruce Lyeth

    2013-06-01

    Full Text Available Traumatic brain injury (TBI is a leading cause of death and disability in the United States. Despite more than 30 years of research, no pharmacological agents have been identified that improve neurological function following TBI. However, several lines of research described in this review provide support for further development of voltage gated calcium channel (VGCC antagonists as potential therapeutic agents. Following TBI, neurons and astrocytes experience a rapid and sometimes enduring increase in intracellular calcium ([Ca2+]i. These fluxes in [Ca2+]i drive not only apoptotic and necrotic cell death, but also can lead to long-term cell dysfunction in surviving cells. In a limited number of in vitro experiments, both L-type and N-type VGCC antagonists successfully reduced calcium loads as well as neuronal and astrocytic cell death following mechanical injury. In rodent models of TBI, administration of VGCC antagonists reduced cell death and improved cognitive function. It is clear that there is a critical need to find effective therapeutics and rational drug delivery strategies for the management and treatment of TBI, and we believe that further investigation of VGCC antagonists should be pursued before ruling out the possibility of successful translation to the clinic.

  15. Antagonistic bioactivity of endophytic strains isolated from Salvia ...

    The antibiotic-producing potential of endophytic populations from medical plant of Salvia miltiorrhiza was examined. A total of 63 isolates was screened against five fungal and three bacterial species for the production of antimicrobial compounds. It showed that more isolates was antagonistic to fungi than to bacteria.

  16. Screening and Mechanism of Trapping Ligand Antagonist Peptide ...

    Purpose: The aim of the present study was to develop peptide H9 as an efficient antagonist of human cytomegalovirus (HCMV) chemokine receptor US28. Methods: US28 gene was amplified from HCMV, and a stable expression system was constructed using NIH/3T3 cells. Interaction between peptide H9 and receptor ...

  17. Reversal strategies for vitamin K antagonists in acute intracerebral hemorrhage

    Parry-Jones, Adrian R.; Di Napoli, Mario; Goldstein, Joshua N.; Schreuder, Floris H B M; Tetri, Sami; Tatlisumak, Turgut; Yan, Bernard; Van Nieuwenhuizen, Koen M.; Dequatre-Ponchelle, Nelly; Lee-Archer, Matthew; Horstmann, Solveig; Wilson, Duncan; Pomero, Fulvio; Masotti, Luca; Lerpiniere, Christine; Godoy, Daniel Agustin; Cohen, Abigail S.; Houben, Rik; Al-Shahi Salman, Rustam; Pennati, Paolo; Fenoglio, Luigi; Werring, David; Veltkamp, Roland; Wood, Edith; Dewey, Helen M.; Cordonnier, Charlotte; Klijn, Catharina J M; Meligeni, Fabrizio; Davis, Stephen M.; Huhtakangas, Juha; Staals, Julie; Rosand, Jonathan; Meretoja, Atte

    2015-01-01

    Objective There is little evidence to guide treatment strategies for intracerebral hemorrhage on vitamin K antagonists (VKA-ICH). Treatments utilized in clinical practice include fresh frozen plasma (FFP) and prothrombin complex concentrate (PCC). Our aim was to compare case fatality with different

  18. Role of muscarinic receptor antagonists in urgency and nocturia

    Michel, Martin C.; de La Rosette, Jean J. M. C. H.

    2005-01-01

    The overactive bladder (OAB) syndrome is defined as urgency, with or without urgency incontinence, usually accompanied by frequency and nocturia. Muscarinic receptor antagonists are the most established form of treatment for OAB, but until recently their effectiveness was only confirmed for symptoms

  19. Characterization of a novel non-steroidal glucocorticoid receptor antagonist

    Li, Qun-Yi; Zhang, Meng; Hallis, Tina M.; DeRosier, Therese A.; Yue, Jian-Min; Ye, Yang; Mais, Dale E.; Wang, Ming-Wei

    2010-01-01

    Selective antagonists of the glucocorticoid receptor (GR) are desirable for the treatment of hypercortisolemia associated with Cushing's syndrome, psychic depression, obesity, diabetes, neurodegenerative diseases, and glaucoma. NC3327, a non-steroidal small molecule with potent binding affinity to GR (K i = 13.2 nM), was identified in a high-throughput screening effort. As a full GR antagonist, NC3327 greatly inhibits the dexamethasone (Dex) induction of marker genes involved in hepatic gluconeogenesis, but has a minimal effect on matrix metalloproteinase 9 (MMP-9), a GR responsive pro-inflammatory gene. Interestingly, the compound recruits neither coactivators nor corepressors to the GR complex but competes with glucocorticoids for the interaction between GR and a coactivator peptide. Moreover, NC3327 does not trigger GR nuclear translocation, but significantly blocks Dex-induced GR transportation to the nucleus, and thus appears to be a 'competitive' GR antagonist. Therefore, the non-steroidal compound, NC3327, may represent a new class of GR antagonists as potential therapeutics for a variety of cortisol-related endocrine disorders.

  20. Efficacy and safety of histamine-2 receptor antagonists

    van der Pol, Rachel; Langendam, Miranda; Benninga, Marc; van Wijk, Michiel; Tabbers, Merit

    2014-01-01

    Histamine-2 receptor antagonists (H2RAs) are frequently used in the treatment of gastroesophageal reflux disease (GERD) in children; however, their efficacy and safety is questionable. To systematically review the literature to assess the efficacy and safety of H2RAs in pediatric GERD. PubMed,

  1. NK-1 receptor antagonists as anti-cancer drugs

    The substance P (SP)/neurokinin (NK)-1 receptor system plays an important role in cancer. SP promotes the proliferation of tumour cells, angiogenesis and the migration of tumour cells. We review the involvement of SP, the NK-1 receptor and NK-1 receptor antagonists in cancer. Tumour cells overexpress NK-1 receptors, ...

  2. An Antagonistic Dialogue about Chaordic Systems Thinking: Part I

    Wafler, Toni

    2004-01-01

    This paper explores the added value of chaordic systems Thinking for organizational renewal, which is defined as transformation instead of reformation. The exploration is presented in the form of an antagonistic dialogue between two "voices," which develop commentaries from distinct theoretical inspirations, namely chaordic systems thinking (CST)…

  3. PARTIAL AGONISTS, FULL AGONISTS, ANTAGONISTS - DILEMMAS OF DEFINITION

    HOYER, D; BODDEKE, HWGM

    The absence of selective antagonists makes receptor characterization difficult, and largely dependent on the use of agonists. However, there has been considerable debate as to whether certain drugs acting at G protein-coupled receptors are better described as agonists, partial agonists or

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

    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...

  5. Enzyme replacement therapy for alpha-mannosidosis

    Borgwardt, Line Gutte; Dali, Christine I.; Fogh, J

    2013-01-01

    Alpha-mannosidosis (OMIM 248500) is a rare lysosomal storage disease (LSD) caused by alpha-mannosidase deficiency. Manifestations include intellectual disabilities, facial characteristics and hearing impairment. A recombinant human alpha-mannosidase (rhLAMAN) has been developed for weekly...

  6. Estrogen increases smooth muscle expression of alpha2C-adrenoceptors and cold-induced constriction of cutaneous arteries.

    Eid, A H; Maiti, K; Mitra, S; Chotani, M A; Flavahan, S; Bailey, S R; Thompson-Torgerson, C S; Flavahan, N A

    2007-09-01

    Raynaud's phenomenon, which is characterized by intense cold-induced constriction of cutaneous arteries, is more common in women compared with men. Cold-induced constriction is mediated in part by enhanced activity of alpha(2C)-adrenoceptors (alpha(2C)-ARs) located on vascular smooth muscle cells (VSMs). Experiments were therefore performed to determine whether 17beta-estradiol regulates alpha(2C)-AR expression and function in cutaneous VSMs. 17beta-Estradiol (0.01-10 nmol/l) increased expression of the alpha(2C)-AR protein and the activity of the alpha(2C)-AR gene promoter in human cultured dermal VSMs, which was assessed following transient transfection of the cells with a promoter-reporter construct. The effect of 17beta-estradiol was associated with increased accumulation of cAMP and activation of the cAMP-responsive Rap2 GTP-binding protein. Transient transfection of VSMs with a dominant-negative mutant of Rap2 inhibited the 17beta-estradiol-induced activation of the alpha(2C)-AR gene promoter, whereas a constitutively active mutant of Rap2 increased alpha(2C)-AR promoter activity. The effects of 17beta-estradiol were inhibited by the estrogen receptor (ER) antagonist, ICI-182780 (1 micromol/l), and were mimicked by a cell-impermeable form of the hormone (estrogen:BSA) or by the selective ER-alpha receptor agonist 4,4',4'''-(4-propyl-[(1)H]-pyrazole-1,3,5-triyl)tris-phenol (PPT; 10 nmol/l) or the selective ER-beta receptor agonist 2,3-bis(4-hydroxyphenyl)-propionitrile (DPN; 10 nmol/l). Therefore, 17beta-estradiol increased expression of alpha(2C)-ARs by interacting with cell surface receptors to cause a cAMP/Rap2-dependent increase in alpha(2C)-AR transcription. In mouse tail arteries, 17beta-estradiol (10 nmol/l) increased alpha(2C)-AR expression and selectively increased the cold-induced amplification of alpha(2)-AR constriction, which is mediated by alpha(2C)-ARs. An estrogen-dependent increase in expression of cold-sensitive alpha(2C)-ARs may contribute

  7. PPAR{alpha} deficiency augments a ketogenic diet-induced circadian PAI-1 expression possibly through PPAR{gamma} activation in the liver

    Oishi, Katsutaka, E-mail: k-ooishi@aist.go.jp [Biological Clock Research Group, Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki (Japan); Uchida, Daisuke [Biological Clock Research Group, Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki (Japan); Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki (Japan); Ohkura, Naoki [Department of Clinical Molecular Biology, Faculty of Pharmaceutical Sciences, Teikyo University, Sagamihara, Kanagawa (Japan); Horie, Shuichi [Department of Clinical Biochemistry, Kagawa Nutrition University, Sakado, Saitama (Japan)

    2010-10-15

    Research highlights: {yields} PPAR{alpha} deficiency augments a ketogenic diet-induced circadian PAI-1 expression. {yields} Hepatic expressions of PPAR{gamma} and PCG-1{alpha} are induced by a ketogenic diet. {yields} PPAR{gamma} antagonist attenuates a ketogenic diet-induced PAI-1 expression. {yields} Ketogenic diet advances the phase of circadian clock in a PPAR{alpha}-independent manner. -- Abstract: An increased level of plasminogen activator inhibitor-1 (PAI-1) is considered a risk factor for cardiovascular diseases, and PAI-1 gene expression is under the control of molecular circadian clocks in mammals. We recently showed that PAI-1 expression is augmented in a phase-advanced circadian manner in mice fed with a ketogenic diet (KD). To determine whether peroxisome proliferator-activated receptor {alpha} (PPAR{alpha}) is involved in hypofibrinolytic status induced by a KD, we examined the expression profiles of PAI-1 and circadian clock genes in PPAR{alpha}-null KD mice. Chronic administration of bezafibrate induced the PAI-1 gene expression in a PPAR{alpha}-dependent manner. Feeding with a KD augmented the circadian expression of PAI-1 mRNA in the hearts and livers of wild-type (WT) mice as previously described. The KD-induced mRNA expression of typical PPAR{alpha} target genes such as Cyp4A10 and FGF21 was damped in PPAR{alpha}-null mice. However, plasma PAI-1 concentrations were significantly more elevated in PPAR{alpha}-null KD mice in accordance with hepatic mRNA levels. These observations suggest that PPAR{alpha} activation is dispensable for KD-induced PAI-1 expression. We also found that hyperlipidemia, fatty liver, and the hepatic expressions of PPAR{gamma} and its coactivator PCG-1{alpha} were more effectively induced in PPAR{alpha}-null, than in WT mice on a KD. Furthermore, KD-induced hepatic PAI-1 expression was significantly suppressed by supplementation with bisphenol A diglycidyl ether, a PPAR{gamma} antagonist, in both WT and PPAR{alpha

  8. Reversal of behavioral depression by infusion of an alpha-2 adrenergic agonist into the locus coeruleus.

    Simson, P G; Weiss, J M; Hoffman, L J; Ambrose, M J

    1986-04-01

    This experiment demonstrated that behavioral depression produced by exposure of rats to strong uncontrollable shocks could be reversed by infusion of the alpha-2 adrenergic agonist clonidine into the region of the locus coeruleus (LC). A 20-min infusion, through bilateral cannulae, into the locus coeruleus of clonidine, piperoxane (alpha-2 antagonist) or inactive vehicle (0.85% saline), was given beginning 70 min after the animals were removed from the stress situation. The dose and volume of drug given in the infusion (0.16 microgram/microliter, 0.1 microliter/min) had been previously shown to produce effects specific to the locus coeruleus (Weiss, Simson, Hoffman, Ambrose, Cooper and Webster, 1986; Neuropharmacology 25: 367-384). At the conclusion of the infusion, active behavior of animals was measured in a 15-min swim test. Results showed that stressed animals infused with vehicle exhibited significantly less active behavior in the swim test than did non-stressed animals infused with vehicle, thereby showing the usual behavioral depression seen after exposure to an uncontrollable stress. Stressed animals infused with clonidine showed no difference in active behavior in comparison to non-stressed animals infused with vehicle and showed significantly more activity than did the stressed animals infused with vehicle. Stressed animals infused with piperoxane showed no significant difference in activity in comparison to the stressed animals infused with vehicle and were significantly less active than either the non-stressed animals infused with vehicle or the stressed animals infused with clonidine. Thus, infusion into the locus coeruleus of the alpha-2 agonist clonidine, but not the alpha-2 antagonist piperoxane, eliminated behavioral depression.(ABSTRACT TRUNCATED AT 250 WORDS)

  9. Hippocampal 3alpha,5alpha-THP may alter depressive behavior of pregnant and lactating rats.

    Frye, Cheryl A; Walf, Alicia A

    2004-07-01

    The 5alpha-reduced metabolite of progesterone (P), 5alpha-pregnan-3alpha-ol-20-one (3alpha,5alpha-THP), may mediate progestins' effects to reduce depressive behavior of female rats in part through actions in the hippocampus. To investigate, forced swim test behavior and plasma and hippocampal progestin levels were assessed in groups of rats expected to differ in their 3alpha,5alpha-THP levels due to endogenous differences (pregnant and postpartum), administration of a 5alpha-reductase inhibitor (finasteride; 50 mg/kg sc), and/or gestational stress [prenatal stress (PNS)], an animal model of depression. Pregnant rats had higher plasma and hippocampal 3alpha,5alpha-THP levels and less depressive behavior (decreased immobility, increased struggling and swimming) in the forced swim test than did postpartum rats. Finasteride, compared to vehicle-administration, reduced plasma and hippocampal 3alpha,5alpha-THP levels and increased depressive behavior (increased immobility, decreased struggling and swimming). PNS was associated with lower hippocampal, but not plasma, 3alpha,5alpha-THP levels and increased swimming compared to that observed in control rats. Together, these data suggest that 3alpha,5alpha-THP in the hippocampus may mediate antidepressive behavior of female rats.

  10. Alternative splicing of T cell receptor (TCR) alpha chain transcripts containing V alpha 1 or V alpha 14 elements.

    Mahotka, C; Hansen-Hagge, T E; Bartram, C R

    1995-10-01

    Human acute lymphoblastic leukemia cell lines represent valuable tools to investigate distinct steps of the complex regulatory pathways underlying T cell receptor recombination and expression. A case in point are V delta 2D delta 3 and subsequent V delta 2D delta 3J alpha rearrangements observed in human leukemic pre-B cells as well as in normal lymphopoiesis. The functional expression of these unusual (VD) delta (JC) alpha hybrids is almost exclusively prevented by alternative splicing events. In this report we show that alternative splicing at cryptic splice donor sites within V elements is not a unique feature of hybrid TCR delta/alpha transcripts. Among seven V alpha families analyzed by RT-PCR, alternatively spliced products were observed in TCR alpha recombinations containing V alpha 1 or V alpha 14 elements. In contrast to normal peripheral blood cells and thymocytes, the leukemia cell line JM expressing functional V alpha 1J alpha 3C alpha transcripts lacked evidence of aberrant TCR alpha RNA species.

  11. Antagonistic interactions between plant competition and insect herbivory.

    Schädler, Martin; Brandl, Roland; Haase, Josephine

    2007-06-01

    Interspecific competition between plants and herbivory by specialized insects can have synergistic effects on the growth and performance of the attacked host plant. We tested the hypothesis that competition between plants may also negatively affect the performance of herbivores as well as their top-down effect on the host plant. In such a case, the combined effects of competition and herbivory may be less than expected from a simple multiplicative response. In other words, competition and herbivory may interact antagonistically. In a greenhouse experiment, Poa annua was grown in the presence or absence of a competitor (either Plantago lanceolata or Trifolium repens), as well as with or without a Poa-specialist aphid herbivore. Both competition and herbivory negatively affected Poa growth. Competition also reduced aphid density on Poa. This effect could in part be explained by changes in the biomass and the nitrogen content of Poa shoots. In treatments with competitors, reduced aphid densities alleviated the negative effect of herbivory on above- and belowground Poa biomass. Hence, we were able to demonstrate an antagonistic interaction between plant-plant interspecific competition and herbivory. However, response indices suggested that antagonistic interactions between competition and herbivory were contingent on the identity of the competitor. We found the antagonistic effect only in treatments with T. repens as the competitor. We conclude that both competitor identity and the herbivore's ability to respond with changes in its density or activity to plant competition affect the magnitude and direction (synergistic vs. antagonistic) of the interaction between competition and herbivory on plant growth.

  12. Blockade of rat alpha3beta4 nicotinic receptor function by methadone, its metabolites, and structural analogs.

    Xiao, Y; Smith, R D; Caruso, F S; Kellar, K J

    2001-10-01

    The opioid agonist properties of (+/-)-methadone are ascribed almost entirely to the (-)-methadone enantiomer. To extend our knowledge of the pharmacological actions of methadone at ligand-gated ion channels, we investigated the effects of the two enantiomers of methadone and its metabolites R-(+)-2-ethyl-1,5-dimethyl-3,3-diphenylpyrrolinium perchlorate (EDDP) and R-(+)-2-ethyl-5-methyl-3,3-diphenyl-1-pyrroline hydrochloride (EMDP), as well as structural analogs of methadone, including (-)-alpha-acetylmethadol hydrochloride (LAAM) and (+)-alpha-propoxyphene, on rat alpha3beta4 neuronal nicotinic acetylcholine receptors (nAChRs) stably expressed in a human embryonic kidney 293 cell line, designated KXalpha3beta4R2. (+/-)-methadone inhibited nicotine-stimulated 86Rb+ efflux from the cells in a concentration-dependent manner with an IC50 value of 1.9 +/- 0.2 microM, indicating that it is a potent nAChR antagonist. The (-)- and (+)-enantiomers of methadone have similar inhibitory potencies on nicotine-stimulated 86Rb+ efflux, with IC50 values of approximately 2 microM. EDDP, the major metabolite of methadone, is even more potent, with an IC50 value of approximately 0.5 microM, making it one of the most potent nicotinic receptor blockers reported. In the presence of (+/-)-methadone, EDDP, or LAAM, the maximum nicotine-stimulated 86Rb+ efflux was markedly decreased, but the EC50 value for nicotine stimulation was altered only slightly, if at all, indicating that these compounds block alpha3beta4 nicotinic receptor function by a noncompetitive mechanism. Consistent with a noncompetitive mechanism, (+/-)-methadone, its metabolites, and structural analogs have very low affinity for nicotinic receptor agonist binding sites in membrane homogenates from KXalpha3beta4R2 cells. We conclude that both enantiomers of methadone and its metabolites as well as LAAM and (+)-alpha-propoxyphene are potent noncompetitive antagonists of alpha3beta4 nAChRs.

  13. alpha-Tocopheryl succinate promotes selective cell death induced by vitamin K3 in combination with ascorbate.

    Tomasetti, M; Strafella, E; Staffolani, S; Santarelli, L; Neuzil, J; Guerrieri, R

    2010-04-13

    A strategy to reduce the secondary effects of anti-cancer agents is to potentiate the therapeutic effect by their combination. A combination of vitamin K3 (VK3) and ascorbic acid (AA) exhibited an anti-cancer synergistic effect, associated with extracellular production of H(2)O(2) that promoted cell death. The redox-silent vitamin E analogue alpha-tocopheryl succinate (alpha-TOS) was used in combination with VK3 and AA to evaluate their effect on prostate cancer cells. Prostate cancer cells were sensitive to alpha-TOS and VK3 treatment, but resistant to AA upto 3.2 mM. When combined, a synergistic effect was found for VK3-AA, whereas alpha-TOS-VK3 and alpha-TOS-AA combination showed an antagonist and additive effect, respectively. However, sub-lethal doses of AA-VK3 combination combined with a sub-toxic dose of alpha-TOS showed to induce efficient cell death that resembles autoschizis. Associated with this cell demise, lipid peroxidation, DNA damage, cytoskeleton alteration, lysosomal-mitochondrial perturbation, and release of cytochrome c without caspase activation were observed. Inhibition of lysosomal proteases did not attenuate cell death induced by the combined agents. Furthermore, cell deaths by apoptosis and autoschizis were detected. These finding support the emerging idea that synergistic combinations of some agents can overcome toxicity and other side-effects associated with high doses of single drugs creating the opportunity for therapeutically relevant selectivity.

  14. Crystalline anhydrous {alpha},{alpha}-trehalose (polymorph {beta}) and crystalline dihydrate {alpha},{alpha}-trehalose: A calorimetric study

    Pinto, Susana S. [Centro de Quimica Estrutural, Complexo Interdisciplinar, Instituto Superior Tecnico, 1049-001 Lisbon (Portugal)]. E-mail: susanapinto@ist.utl.pt; Diogo, Herminio P. [Centro de Quimica Estrutural, Complexo Interdisciplinar, Instituto Superior Tecnico, 1049-001 Lisbon (Portugal)]. E-mail: hdiogo@ist.utl.pt; Moura-Ramos, Joaquim J. [Centro de Quimica-Fisica Molecular, Complexo Interdisciplinar, Instituto Superior Tecnico, 1049-001 Lisbon (Portugal)]. E-mail: mouraramos@ist.utl.pt

    2006-09-15

    The mean values of the standard massic energy of combustion of crystalline anhydrous {alpha},{alpha}-trehalose (C{sub 12}H{sub 22}O{sub 11}, polymorph {beta}) and crystalline dihydrate {alpha},{alpha}-trehalose (C{sub 12}H{sub 26}O{sub 13}) measured by static-bomb combustion calorimetry in oxygen, at the temperature T=298.15K, are {delta}{sub c}u{sup o}=-(16434.05+/-4.50)J.g{sup -1} and {delta}{sub c}u{sup o}=-(14816.05+/-3.52)J.g{sup -1}, respectively. The standard (p{sup o}=0.1MPa) molar enthalpy of formation of these compounds were derived from the corresponding standard molar enthalpies of combustion, respectively, {delta}{sub f}H{sub m}{sup o} (C{sub 12}H{sub 22}O{sub 11},cr)=-(2240.9+/-3.9)kJ.mol{sup -1}, and {delta}{sub f}H{sub m}{sup o} (C{sub 12}H{sub 26}O{sub 13},cr)=-(2832.6+/-3.6)kJ.mol{sup -1}. The values of the standard enthalpies of formation obtained in this work, together with data on enthalpies of solution at infinite dilution ({delta}{sub sol}H{sup {approx}}) for crystalline dihydrate and amorphous anhydrous trehalose, allow a better insight on the thermodynamic description of the trehalose system which can provide, together with the future research on the subject, a contribution for understanding the metabolism in several organisms, as well as the phase transition between the different polymorphs.

  15. Optimal Trading with Alpha Predictors

    Filippo Passerini; Samuel E. Vazquez

    2015-01-01

    We study the problem of optimal trading using general alpha predictors with linear costs and temporary impact. We do this within the framework of stochastic optimization with finite horizon using both limit and market orders. Consistently with other studies, we find that the presence of linear costs induces a no-trading zone when using market orders, and a corresponding market-making zone when using limit orders. We show that, when combining both market and limit orders, the problem is furthe...

  16. Anti-Parkinson effects of a selective alpha2C-adrenoceptor antagonist in the MPTP marmoset model

    Philippens, I.H.C.H.M.; Joosen, M.J.A.; Ahnaou, A.; Andres, I.; Drinkenburg, W.H.I.M.

    2014-01-01

    Current dopamine replacement therapies, in Parkinson's disease (PD), result in aversive side effects and rapid drug dose escalation over time. Therefore, a non-dopaminergic treatment would be an advantageous supplement to lower the dose of dopamine replacement treatment postponing the occurrence of

  17. Plasma drug concentrations and clinical effects of a peripheral alpha-2-adrenoceptor antagonist, MK-467, in horses sedated with detomidine.

    Vainionpää, Mari H; Raekallio, Marja R; Pakkanen, Soile A E; Ranta-Panula, Ville; Rinne, Valtteri M; Scheinin, Mika; Vainio, Outi M

    2013-05-01

    To investigate plasma drug concentrations and the effect of MK-467 (L-659'066) on sedation, heart rate and gut motility in horses sedated with intravenous (IV) detomidine. Experimental randomized blinded crossover study. Six healthy horses. Detomidine (10 μg kg(-1) IV) was administered alone (DET) and in combination with MK-467 (250 μg kg(-1) IV; DET + MK). The level of sedation and intestinal sounds were scored. Heart rate (HR) and central venous pressure (CVP) were measured. Blood was collected to determine plasma drug concentrations. Repeated measures anova was used for HR, CVP and intestinal sounds, and the Student's t-test for pairwise comparisons between treatments for the area under the time-sedation curve (AUCsed ) and pharmacokinetic parameters. Significance was set at p Detomidine-induced intestinal hypomotility was prevented by MK-467. AUCsed was significantly higher with DET than DET + MK, but maximal sedations scores did not differ significantly between treatments. MK-467 lowered the AUC of the plasma concentration of detomidine, and increased its volume of distribution and clearance. MK-467 prevented detomidine induced bradycardia and intestinal hypomotility. MK-467 did not affect the clinical quality of detomidine-induced sedation, but the duration of the effect was reduced, which may have been caused by the effects of MK-467 on the plasma concentration of detomidine. MK-467 may be useful clinically in the prevention of certain peripheral side effects of detomidine in horses. © 2013 The Authors. Veterinary Anaesthesia and Analgesia © 2013 Association of Veterinary Anaesthetists and the American College of Veterinary Anesthesia and Analgesia.

  18. Alpha particles detection in nitrocellulose

    Romero C, M.

    1976-01-01

    The method for the manufacturing of the detection films follows these steps: preparation of the mass which includes nitrocellulose in the form of cotton as raw material ethyl acetate, cellosolve acetate, isopropyl and butyl alcohols as solvents and dioctyl phtalate as plasticiser; dilution of the paste; pouring of the diluted mass; and drying of the detection films. The results obtained experimentally are: The determination of the development times of the different thicknesses of the manufactured films. Response linearity of the detectors, variation of the number of tracks according to the distance of the source to the detector. Sizes of the diameter of the tracks depending of the distance detector-alpha emmission source. As a conclusion we can say the the nitrocellulose detectors are specific for alpha radiation; the more effective thicknesses in uranium prospecting works were those of 60 microns, since for the laboratory works the thicknesses of 30 to 40 microns were the ideal; the development technique of the detection films is simple and cheap and can be realized even in another place than the laboratory; this way of the manufacturing of nitrocellulose detection film sensitive to alpha nuclear radiation is open to future research. (author)

  19. Shifting to a non-vitamin K antagonist oral anticoagulation agent from vitamin K antagonist in atrial fibrillation

    Fosbøl, Emil L; Vinding, Naja Emborg; Lamberts, Morten

    2017-01-01

    Aims: After non-vitamin K antagonist (VKA) oral anticoagulation agents (NOAC) have been approved for thrombo-embolic prophylaxis in non-valvular atrial fibrillation (NVAF), utilization of oral anticoagulants (OAC) in NVAF has changed. Contemporary shifting from a VKA to a NOAC (dabigatran...

  20. Alpha and beta detection and spectrometry

    Saro, S.

    1984-01-01

    The theory of alpha and beta radioactive decay, the interaction of alpha and beta particles with matter, and their detection and spectrometry are dealt with in seven chapters: 1. Alpha transformation of atomic nuclei; 2. Basic properties of detectors and statistics of detection; 3. Alpha detectors and spectrometers; 4. Applications of alpha detection and spectrometry; 5. Beta transformation of atomic nuclei; 6. Beta particle detectors and spectrometers; 7. Detection of low energy beta particles. Chapter 8 is devoted to sampling and preparation of samples for radiometry. (E.F.)

  1. Innovations in Los Alamos alpha box design

    Ledbetter, J.M.; Dowler, K.E.; Cook, J.H.

    1985-01-01

    Destructive examinations of irradiated fuel pins containing plutonium fuel must be performed in shielded hot cells with strict provisions for containing the plutonium. Alpha boxes provide containment for the plutonium, toxic fission products, and other hazardous highly radioactive materials. The alpha box contains windows for viewing and a variety of transfer systems specially designed to allow transfers in and out of the alpha box without spread of the hazardous materials that are contained in the box. Alpha boxes have been in use in the Wing 9 hot cells at Los Alamos National Laboratory for more than 20 years. Features of the newly designed alpha boxes are presented

  2. Measurement and analysis of $\\alpha$ particle induced reactions on yttrium

    Singh, N L; Chintalapudi, S N

    2000-01-01

    Excitation functions for /sup 89/Y[( alpha ,3n); ( alpha ,4n); ( alpha , p3n); ( alpha , alpha n); ( alpha , alpha 2n)] reactions were measured up to 50 MeV using stacked foil activation technique and HPGe gamma ray spectroscopy method. The experimental data were compared with calculations considering equilibrium as well as preequilibrium reactions according to the hybrid model of Blann (ALICE/90). For ( alpha , xnyp) type of reactions, the precompound contributions are described by the model. There seems to be indications of direct inelastic scattering effects in ( alpha , alpha xn) type of reactions. To the best of our knowledge, the excitation functions for ( alpha ,4n), ( alpha , p3n), ( alpha , alpha n) and ( alpha , alpha 2n) reactions were measured for the first time. (23 refs).

  3. Measurement and analysis of alpha particle induced reactions on yttrium

    Singh, N.L.; Gadkari, M.S. [Baroda Univ. (India). Dept. of Physics; Chintalapudi, S.N. [IUC-DAEF Calcutta Centre, Calcutta (India)

    2000-05-01

    Excitation functions for {sup 89}Y[({alpha},3n);({alpha},4n);({alpha},p3n);({alpha},{alpha}n);({alpha},{alpha}2n)] reactions were measured up to 50 MeV using stacked foil activation technique and HPGe gamma ray spectroscopy method. The experimental data were compared with calculations considering equilibrium as well as preequilibrium reactions according to the hybrid model of Blann (ALICE/90). For ({alpha},xnyp) type of reactions, the precompound contributions are described by the model. There seems to be indications of direct inelastic scattering effects in ({alpha},{alpha}xn) type of reactions. To the best of our knowledge, the excitation functions for ({alpha},4n), ({alpha},p3n), ({alpha},{alpha}n) and ({alpha},{alpha}2n) reactions were measured for the first time. (orig.)

  4. The heavy quarkonium spectrum at order $m\\alpha_{s}^{5}\\ln\\alpha_{s}$

    Brambilla, Nora; Soto, Joan; Vairo, Antonio

    1999-01-01

    We compute the complete leading-log terms of the next-to-next-to-next-to-leading-order corrections to potential NRQCD. As a by-product we obtain the leading logs at $O(m\\alpha_s^5)$ in the heavy quarkonium spectrum. These leading logs, when $\\Lambda_{QCD} \\ll m\\alpha_s^2$, give the complete $O(m\\alpha_s^5 \\ln \\alpha_s)$ corrections to the heavy quarkonium spectrum.

  5. THE LYMAN ALPHA REFERENCE SAMPLE: EXTENDED LYMAN ALPHA HALOS PRODUCED AT LOW DUST CONTENT

    Hayes, Matthew [Universite de Toulouse, UPS-OMP, IRAP, Toulouse (France); Oestlin, Goeran; Duval, Florent; Guaita, Lucia; Melinder, Jens; Sandberg, Andreas [Department of Astronomy, Oskar Klein Centre, Stockholm University, AlbaNova University Centre, SE-106 91 Stockholm (Sweden); Schaerer, Daniel [CNRS, IRAP, 14, avenue Edouard Belin, F-31400 Toulouse (France); Verhamme, Anne; Orlitova, Ivana [Geneva Observatory, University of Geneva, 51 Chemin des Maillettes, CH-1290 Versoix (Switzerland); Mas-Hesse, J. Miguel; Oti-Floranes, Hector [Centro de Astrobiologia (CSIC-INTA), Departamento de Astrofisica, POB 78, 28691 Villanueva de la Canada (Spain); Adamo, Angela [Max Planck Institute for Astronomy, Koenigstuhl 17, D-69117 Heidelberg (Germany); Atek, Hakim [Laboratoire d' Astrophysique, Ecole Polytechnique Federale de Lausanne (EPFL), Observatoire, CH-1290 Sauverny (Switzerland); Cannon, John M. [Department of Physics and Astronomy, Macalester College, 1600 Grand Avenue, Saint Paul, MN 55105 (United States); Herenz, E. Christian [Leibniz-Institut fuer Astrophysik (AIP), An der Sternwarte 16, D-14482 Potsdam (Germany); Kunth, Daniel [Institut d' Astrophysique de Paris, UMR 7095 CNRS and UPMC, 98 bis Bd Arago, F-75014 Paris (France); Laursen, Peter, E-mail: matthew@astro.su.se [Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, DK-2100 Copenhagen (Denmark)

    2013-03-10

    We report on new imaging observations of the Lyman alpha emission line (Ly{alpha}), performed with the Hubble Space Telescope, that comprise the backbone of the Lyman alpha Reference Sample. We present images of 14 starburst galaxies at redshifts 0.028 < z < 0.18 in continuum-subtracted Ly{alpha}, H{alpha}, and the far ultraviolet continuum. We show that Ly{alpha} is emitted on scales that systematically exceed those of the massive stellar population and recombination nebulae: as measured by the Petrosian 20% radius, R{sub P20}, Ly{alpha} radii are larger than those of H{alpha} by factors ranging from 1 to 3.6, with an average of 2.4. The average ratio of Ly{alpha}-to-FUV radii is 2.9. This suggests that much of the Ly{alpha} light is pushed to large radii by resonance scattering. Defining the Relative Petrosian Extension of Ly{alpha} compared to H{alpha}, {xi}{sub Ly{alpha}} = R {sup Ly{alpha}}{sub P20}/R {sup H{alpha}}{sub P20}, we find {xi}{sub Ly{alpha}} to be uncorrelated with total Ly{alpha} luminosity. However, {xi}{sub Ly{alpha}} is strongly correlated with quantities that scale with dust content, in the sense that a low dust abundance is a necessary requirement (although not the only one) in order to spread Ly{alpha} photons throughout the interstellar medium and drive a large extended Ly{alpha} halo.

  6. Inhibition of K+ permeability diminishes alpha 2-adrenoceptor mediated effects on norepinephrine release

    Zimanyi, I.; Folly, G.; Vizi, E.S.

    1988-01-01

    The effect of two different potassium channel blockers, 4-aminopyridine (4-AP) and quinine, on the alpha 2-adrenoceptor mediated modulation of norepinephrine (NE) release was investigated. Pairs of mouse vasa deferentia were loaded with 3 H-norepinephrine ( 3 H-NE), superfused continuously, and stimulated electrically. 4-AP (5.3 x 10(-4) M), and quinine (10(-5) M) enhanced the stimulation-evoked release of tritium significantly. The electrically induced release of radioactivity was reduced by alpha 2-adrenoceptor agonists (1-NE and xylazine) and enhanced by the alpha 2-adrenoceptor antagonist yohimbine. Both effects were affected markedly by 4-AP or quinine: the depressant action of 1-NA and xylazine was partially antagonized and the facilitatory effect of yohimbine was completely abolished during the blockade of the potassium channels. It is suggested that the blockade of the potassium permeability counteracts negative feedback modulation; therefore, it seems likely that the stimulation of alpha 2-adrenoceptors leads to an enhanced potassium permeability and hyperpolarization of varicose axon terminals

  7. Agonist-induced affinity alterations of a central nervous system. cap alpha. -bungarotoxin receptor

    Lukas, R.J.; Bennett, E.L.

    1979-01-01

    The ability of cholinergic agonists to block the specific interaction of ..cap alpha..-bungarotoxin (..cap alpha..-Bgt) with membrane-bound sites derived from rat brain is enhanced when membranes are preincubated with agonist. Thus, pretreatment of ..cap alpha..-Bgt receptors with agonist (but not antagonist) causes transformation of sites to a high-affinity form toward agonist. This change in receptor state occurs with a half-time on the order of minutes, and is fully reversible on dilution of agonist. The results are consistent with the identity of ..cap alpha..-Bgt binding sites as true central nicotinic acetylcholine receptors. Furthermore, this agonist-induced alteration in receptor state may represent an in vitro correlate of physiological desensitization. As determined from the effects of agonist on toxin binding isotherms, and on the rate of toxin binding to specific sites, agonist inhibition of toxin binding to the high-affinity state is non-competitive. This result suggests that there may exist discrete toxin-binding and agonist-binding sites on central toxin receptors.

  8. alpha-Adrenoceptor and opioid receptor modulation of clonidine-induced antinociception.

    Sierralta, F; Naquira, D; Pinardi, G; Miranda, H F

    1996-10-01

    1. The antinociceptive action of clonidine (Clon) and the interactions with alpha 1, alpha 2 adrenoceptor and opioid receptor antagonists was evaluated in mice by use of chemical algesiometric test (acetic acid writhing test). 2. Clon produced a dose-dependent antinociceptive action and the ED50 for intracerebroventricular (i.c.v.) was lower than for intraperitoneal (i.p.) administration (1 ng kg-1 vs 300 ng kg-1). The parallelism of the dose-response curves indicates activation of a common receptor subtype. 3. Systemic administration of prazosin and terazosin displayed antinociceptive activity. Pretreatment with prazosin produced a dual action: i.c.v. Clon effect did not change, and i.p. Clon effect was enhanced. Yohimbine i.c.v. or i.p. did not induce antinonciception, but antagonized Clon-induced activity. These results suggest that alpha 1- and alpha 2-adrenoceptors, either located at the pre- and/or post-synaptic level, are involved in the control of spinal antinociception. 4. Naloxone (NX) and naltrexone (NTX) induced antinociceptive effects at low doses (microgram kg-1 range) and a lower antinociceptive effect at higher doses (mg kg-1 range). Low doses of NX or NTX antagonized Clon antinociception, possibly in relation to a preferential mu opioid receptor antagonism. In contrast, high doses of NX or NTX increased the antinociceptive activity of Clon, which could be due to an enhanced inhibition of the release of substance P. 5. The results obtained in the present work suggest the involvement of alpha 1-, alpha 2-adrenoceptor and opioid receptors in the modulation of the antinociceptive activity of clonidine, which seems to be exerted either at spinal and/or supraspinal level.

  9. Novel drugs that target the estrogen-related receptor alpha: their therapeutic potential in breast cancer

    May, Felicity EB, E-mail: F.E.B.May@ncl.ac.uk [Northern Institute for Cancer Research and Department of Pathology, Faculty of Medical Sciences, University of Newcastle upon Tyne, Newcastle upon Tyne (United Kingdom)

    2014-05-23

    The incidence of breast cancer continues to rise: 1.7 million women were diagnosed with and 521,000 women died from breast cancer in 2012. This review considers first current treatment options: surgery; radiotherapy; and systemic endocrine, anti-biological, and cytotoxic therapies. Clinical management includes prevention, early detection by screening, treatment with curative intent, management of chronic disease, and palliative control of advanced breast cancer. Next, the potential of novel drugs that target DNA repair, growth factor dependence, intracellular and intercellular signal transduction, and cell cycle are considered. Estrogen-related receptor alpha has attracted attention as a therapeutic target in triple-negative breast cancers with de novo resistance to, and in breast cancers with acquired resistance to, endocrine therapies such as antiestrogens and aromatase inhibitors. Estrogen-related receptor alpha is an orphan receptor and transcription factor. Its activity is regulated by coregulator proteins and posttranslational modification. It is an energy sensor that controls adaptation to energy demand and may facilitate glycolytic metabolism and mitochondrial oxidative respiration in breast cancer cells. Estrogen-related receptor alpha increases breast cancer cell migration, proliferation, and tumor development. It is expressed at high levels in estrogen receptor-negative tumors, and is proposed to activate estrogen-responsive genes in endocrine-resistant tumors. The structures and functions of the ligand-binding domains of estrogen receptor alpha and estrogen-related receptor alpha, their ability to bind estrogens, phytoestrogens, and synthetic ligands, and the effects of ligand agonists, antagonists, and inverse agonists on biological activity, are evaluated. Synthetic ligands of estrogen-related receptor alpha have activity in preclinical models of metabolic disorders, diabetes, osteoporosis, and oncology. The clinical settings in which these novel

  10. Novel drugs that target the estrogen-related receptor alpha: their therapeutic potential in breast cancer

    May, Felicity EB

    2014-01-01

    The incidence of breast cancer continues to rise: 1.7 million women were diagnosed with and 521,000 women died from breast cancer in 2012. This review considers first current treatment options: surgery; radiotherapy; and systemic endocrine, anti-biological, and cytotoxic therapies. Clinical management includes prevention, early detection by screening, treatment with curative intent, management of chronic disease, and palliative control of advanced breast cancer. Next, the potential of novel drugs that target DNA repair, growth factor dependence, intracellular and intercellular signal transduction, and cell cycle are considered. Estrogen-related receptor alpha has attracted attention as a therapeutic target in triple-negative breast cancers with de novo resistance to, and in breast cancers with acquired resistance to, endocrine therapies such as antiestrogens and aromatase inhibitors. Estrogen-related receptor alpha is an orphan receptor and transcription factor. Its activity is regulated by coregulator proteins and posttranslational modification. It is an energy sensor that controls adaptation to energy demand and may facilitate glycolytic metabolism and mitochondrial oxidative respiration in breast cancer cells. Estrogen-related receptor alpha increases breast cancer cell migration, proliferation, and tumor development. It is expressed at high levels in estrogen receptor-negative tumors, and is proposed to activate estrogen-responsive genes in endocrine-resistant tumors. The structures and functions of the ligand-binding domains of estrogen receptor alpha and estrogen-related receptor alpha, their ability to bind estrogens, phytoestrogens, and synthetic ligands, and the effects of ligand agonists, antagonists, and inverse agonists on biological activity, are evaluated. Synthetic ligands of estrogen-related receptor alpha have activity in preclinical models of metabolic disorders, diabetes, osteoporosis, and oncology. The clinical settings in which these novel

  11. Thiols in the alphaIIbbeta3 integrin are necessary for platelet aggregation.

    Manickam, Nagaraj; Sun, Xiuhua; Hakala, Kevin W; Weintraub, Susan T; Essex, David W

    2008-07-01

    Sulfhydryl groups of platelet surface proteins are important in platelet aggregation. While p-chloromercuribenzene sulphonate (pCMBS) has been used in most studies on platelet surface thiols, the specific thiol-proteins that pCMBS reacts with to inhibit aggregation have not been well defined. Since the thiol-containing P2Y(12) ADP receptor is involved in most types of platelet aggregation, we used the ADP scavenger apyrase and the P2Y(12) receptor antagonist 2-MeSAMP to examine thiol-dependent reactions in the absence of contributions from this receptor. We provide evidence for a non-P2Y(12) thiol-dependent reaction near the final alphaIIbbeta3-dependent events of aggregation. We then used 3-(N-maleimidylpropionyl)biocytin (MPB) and pCMBS to study thiols in alphaIIbbeta3. As previously reported, disruption of the receptor was required to obtain labelling of thiols with MPB. Specificity of labelling for thiols in the alphaIIb and beta3 subunits was confirmed by identification of the purified proteins by mass spectrometry and by inhibition of labelling with 5,5'-dithiobis-(2-nitrobenzoic acid). In contrast to MPB, pCMBS preferentially reacted with thiols in alphaIIbbeta3 and blocked aggregation under physiological conditions. Similarly, pCMBS preferentially inhibited signalling-independent activation of alphaIIbbeta3 by Mn(2+). Our results suggest that the thiols in alphaIIbbeta3 that are blocked by pCMBS are important in the activation of this integrin.

  12. Ligands specify estrogen receptor alpha nuclear localization and degradation

    Caze-Subra Stéphanie

    2010-12-01

    Full Text Available Abstract Background The estrogen receptor alpha (ERα is found predominately in the nucleus, both in hormone stimulated and untreated cells. Intracellular distribution of the ERα changes in the presence of agonists but the impact of different antiestrogens on the fate of ERα is a matter of debate. Results A MCF-7 cell line stably expressing GFP-tagged human ERα (SK19 cell line was created to examine the localization of ligand-bound GFP-ERα. We combined digitonin-based cell fractionation analyses with fluorescence and immuno-electron microscopy to determine the intracellular distribution of ligand-bound ERα and/or GFP-ERα. Using fluorescence- and electron microscopy we demonstrate that both endogenous ERα and GFP-ERα form numerous nuclear focal accumulations upon addition of agonist, 17β-estradiol (E2, and pure antagonists (selective estrogen regulator disruptor; SERD, ICI 182,780 or RU58,668, while in the presence of partial antagonists (selective estrogen regulator modulator; SERM, 4-hydroxytamoxifen (OHT or RU39,411, diffuse nuclear staining persisted. Digitonin based cell fractionation analyses confirmed that endogenous ERα and GFP-ERα predominantly reside in the nuclear fraction. Overall ERα protein levels were reduced after estradiol treatment. In the presence of SERMs ERα was stabilized in the nuclear soluble fraction, while in the presence of SERDs protein levels decreased drastically and the remaining ERα was largely found in a nuclear insoluble fraction. mRNA levels of ESR1 were reduced compared to untreated cells in the presence of all ligands tested, including E2. E2 and SERDs induced ERα degradation occurred in distinct nuclear foci composed of ERα and the proteasome providing a simple explanation for ERα sequestration in the nucleus. Conclusions Our results indicate that chemical structure of ligands directly affect the nuclear fate and protein turnover of the estrogen receptor alpha independently of their impact on

  13. Receptor protection studies comparing recombinant and native nicotinic receptors: Evidence for a subpopulation of mecamylamine-sensitive native alpha3beta4* nicotinic receptors.

    Free, R Benjamin; Kaser, Daniel J; Boyd, R Thomas; McKay, Dennis B

    2006-01-09

    Studies involving receptor protection have been used to define the functional involvement of specific receptor subtypes in tissues expressing multiple receptor subtypes. Previous functional studies from our laboratory demonstrate the feasibility of this approach when applied to neuronal tissues expressing multiple nicotinic acetylcholine receptors (nAChRs). In the current studies, the ability of a variety of nAChR agonists and antagonists to protect native and recombinant alpha3beta4 nAChRs from alkylation were investigated using nAChR binding techniques. Alkylation of native alpha3beta4* nAChRs from membrane preparations of bovine adrenal chromaffin cells resulted in a complete loss of specific [(3)H]epibatidine binding. This loss of binding to native nAChRs was preventable by pretreatment with the agonists, carbachol or nicotine. The partial agonist, cytisine, produced partial protection. Several nAChR antagonists were also tested for their ability to protect. Hexamethonium and decamethonium were without protective activity while mecamylamine and tubocurarine were partially effective. Addition protection studies were performed on recombinant alpha3beta4 nAChRs. As with native alpha3beta4* nAChRs, alkylation produced a complete loss of specific [(3)H]epibatidine binding to recombinant alpha3beta4 nAChRs which was preventable by pretreatment with nicotine. However, unlike native alpha3beta4* nAChRs, cytisine and mecamylamine, provide no protection for alkylation. These results highlight the differences between native alpha3beta4* nAChRs and recombinant alpha3beta4 nAChRs and support the use of protection assays to characterize native nAChR subpopulations.

  14. Alpha 1-adrenergic stimulation of phosphatidylinositol turnover and respiration of brown fat cells

    Mohell, N.; Wallace, M.; Fain, J.N.

    1984-01-01

    The alpha-adrenergic agonist phenylephrine (in the presence of the beta-adrenergic antagonist alprenolol) stimulated respiration and incorporation of [ 3 H]glycerol and [ 32 P] P/sub i/ into phosphatidylinositol of hamster brown fat cells in a concentration-dependent manner. Both responses were preferentially inhibited by prazosin as compared with yohimbine, indicating alpha 1 specificity. Uniquely, prazosin inhibition of phenylephrine-stimulated phosphatidylinositol metabolism had two components, since 30% of the response was inhibited by less than 1 nM prazosin, 10 nM gave no further inhibition, and 100 nM prazosin completely inhibited the response. The phosphatidylinositol response was still present in Ca 2 +-free buffer, although reduced in magnitude. The concentration relationships of the effects of agonists and antagonists were compared with those of previous results of [ 3 H]prazosin binding and with phenylephrine potency to compete for binding. On the basis of these comparisons, it is suggested that the highly prazosin-sensitive part of the phosphatidylinositol response may be closely associated with receptor occupation

  15. Locus coeruleus alpha-adrenergic-mediated activation of cortical astrocytes in vivo.

    Bekar, Lane K; He, Wei; Nedergaard, Maiken

    2008-12-01

    The locus coeruleus (LC) provides the sole source of norepinephrine (NE) to the cortex for modulation of cortical synaptic activity in response to salient sensory information. NE has been shown to improve signal-to-noise ratios, sharpen receptive fields and function in learning, memory, and cognitive performance. Although LC-mediated effects on neurons have been addressed, involvement of astrocytes has thus far not been demonstrated in these neuromodulatory functions. Here we show for the 1st time in live mice, that astrocytes exhibit rapid Ca(2+) increases in response to electrical stimulation of the LC. Additionally, robust peripheral stimulation known to result in phasic LC activity leads to Ca(2+) responses in astrocytes throughout sensory cortex that are independent of sensory-driven glutamate-dependent pathways. Furthermore, the astrocytic Ca(2+) transients are competitively modulated by alpha(2)-specific agonist/antagonist combinations known to impact LC output, are sensitive to the LC-specific neurotoxin N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine, and are inhibited locally by an alpha-adrenergic antagonist. Future investigations of LC function must therefore consider the possibility that LC neuromodulatory effects are in part derived from activation of astrocytes.

  16. Nonequivalence of alpha-bungarotoxin binding sites in the native nicotinic receptor molecule

    Conti-Tronconi, B.M.; Tang, F.; Walgrave, S.; Gallagher, W.

    1990-01-01

    In the native, membrane-bound form of the nicotinic acetylcholine receptor (M-AcChR) the two sites for the cholinergic antagonist alpha-bungarotoxin (alpha-BGT) have different binding properties. One site has high affinity, and the M-AcChR/alpha-BGT complexes thus formed dissociate very slowly, similar to the complexes formed with detergent-solubilized AcChR (S-AcChR). The second site has much lower affinity (KD approximately 59 +/- 35 nM) and forms quickly reversible complexes. The nondenaturing detergent Triton X-100 is known to solubilize the AcChR in a form unable, upon binding of cholinergic ligands, to open the ion channel and to become desensitized. Solubilization of the AcChR in Triton X-100 affects the binding properties of this second site and converts it to a high-affinity, slowly reversible site. Prolonged incubation of M-AcChR at 4 degrees C converts the low-affinity site to a high-affinity site similar to those observed in the presence of Triton X-100. Although the two sites have similar properties when the AcChR is solubilized in Triton X-100, their nonequivalence can be demonstrated by the effect on alpha-BGT binding of concanavalin A, which strongly reduces the association rate of one site only. The Bmax of alpha-BGT to either Triton-solubilized AcChR or M-AcChR is not affected by the presence of concanavalin A. Occupancy of the high-affinity, slowly reversible site in M-AcChR inhibits the Triton X-100 induced conversion to irreversibility of the second site. At difference with alpha-BGT, the long alpha-neurotoxin from Naja naja siamensis venom (alpha-NTX) binds with high affinity and in a very slowly reversible fashion to two sites in the M-AcChR. We confirm here that Triton-solubilized AcChR or M-AcChR binds in a very slowly reversible fashion the same amount of alpha-NTX

  17. GnRH antagonist versus long agonist protocols in IVF

    Lambalk, C B; Banga, F R; Huirne, J A

    2017-01-01

    BACKGROUND: Most reviews of IVF ovarian stimulation protocols have insufficiently accounted for various patient populations, such as ovulatory women, women with polycystic ovary syndrome (PCOS) or women with poor ovarian response, and have included studies in which the agonist or antagonist...... was not the only variable between the compared study arms. OBJECTIVE AND RATIONALE: The aim of the current study was to compare GnRH antagonist protocols versus standard long agonist protocols in couples undergoing IVF or ICSI, while accounting for various patient populations and treatment schedules. SEARCH...... in couples undergoing IVF or ICSI. The primary outcome was ongoing pregnancy rate. Secondary outcomes were: live birth rate, clinical pregnancy rate, number of oocytes retrieved and safety with regard to ovarian hyperstimulation syndrome (OHSS). Separate comparisons were performed for the general IVF...

  18. Interleukin-1-receptor antagonist in type 2 diabetes mellitus

    Larsen, Claus M; Faulenbach, Mirjam; Vaag, Allan

    2007-01-01

    BACKGROUND: The expression of interleukin-1-receptor antagonist is reduced in pancreatic islets of patients with type 2 diabetes mellitus, and high glucose concentrations induce the production of interleukin-1beta in human pancreatic beta cells, leading to impaired insulin secretion, decreased cell...... proliferation, and apoptosis. METHODS: In this double-blind, parallel-group trial involving 70 patients with type 2 diabetes, we randomly assigned 34 patients to receive 100 mg of anakinra (a recombinant human interleukin-1-receptor antagonist) subcutaneously once daily for 13 weeks and 36 patients to receive...... placebo. At baseline and at 13 weeks, all patients underwent an oral glucose-tolerance test, followed by an intravenous bolus of 0.3 g of glucose per kilogram of body weight, 0.5 mg of glucagon, and 5 g of arginine. In addition, 35 patients underwent a hyperinsulinemic-euglycemic clamp study. The primary...

  19. Serotonin 2A receptor antagonists for treatment of schizophrenia

    Ebdrup, Bjørn Hylsebeck; Rasmussen, Hans; Arnt, Jørn

    2011-01-01

    Introduction: All approved antipsychotic drugs share an affinity for the dopamine 2 (D2) receptor; however, these drugs only partially ameliorate the symptoms of schizophrenia. It is, therefore, of paramount importance to identify new treatment strategies for schizophrenia. Areas covered......: Preclinical, clinical and post-mortem studies of the serotonin 5-HT2A system in schizophrenia are reviewed. The implications of a combined D2 and 5-HT2A receptor blockade, which is obtained by several current antipsychotic drugs, are discussed, and the rationale for the development of more selective 5-HT2A...... receptor antagonists is evaluated. Moreover, the investigational pipeline of major pharmaceutical companies is examined and an Internet search conducted to identify other pharmaceutical companies investigating 5-HT2A receptor antagonists for the treatment of schizophrenia. Expert opinion: 5-HT2A receptor...

  20. Cyclic degradation of antagonistic shape memory actuated structures

    Sofla, A Y N; Elzey, D M; Wadley, H N G

    2008-01-01

    Antagonistic shape memory actuated structures exploit opposing pairs of one-way shape memory alloy (SMA) linear actuators to create devices capable of a fully reversible response. Unlike many conventional reversible SMA devices they do not require bias force components (springs) to return them to their pre-actuated configuration. However, the repeated use of SMA antagonistic devices results in the accumulation of plastic strain in the actuators which can diminish their actuation stroke. We have investigated this phenomenon and the effect of shape memory alloy pre-strain upon it for near equi-atomic NiTi actuators. We find that the degradation eventually stabilizes during cycling. A thermomechanical treatment has been found to significantly reduce degradation in cyclic response of the actuators

  1. In-silico guided discovery of novel CCR9 antagonists

    Zhang, Xin; Cross, Jason B.; Romero, Jan; Heifetz, Alexander; Humphries, Eric; Hall, Katie; Wu, Yuchuan; Stucka, Sabrina; Zhang, Jing; Chandonnet, Haoqun; Lippa, Blaise; Ryan, M. Dominic; Baber, J. Christian

    2018-03-01

    Antagonism of CCR9 is a promising mechanism for treatment of inflammatory bowel disease, including ulcerative colitis and Crohn's disease. There is limited experimental data on CCR9 and its ligands, complicating efforts to identify new small molecule antagonists. We present here results of a successful virtual screening and rational hit-to-lead campaign that led to the discovery and initial optimization of novel CCR9 antagonists. This work uses a novel data fusion strategy to integrate the output of multiple computational tools, such as 2D similarity search, shape similarity, pharmacophore searching, and molecular docking, as well as the identification and incorporation of privileged chemokine fragments. The application of various ranking strategies, which combined consensus and parallel selection methods to achieve a balance of enrichment and novelty, resulted in 198 virtual screening hits in total, with an overall hit rate of 18%. Several hits were developed into early leads through targeted synthesis and purchase of analogs.

  2. Are peripheral opioid antagonists the solution to opioid side effects?

    Bates, John J

    2012-02-03

    Opioid medication is the mainstay of therapy for severe acute and chronic pain. Unfortunately, the side effects of these medications can affect patient comfort and safety, thus limiting their proven therapeutic potential. Whereas the main analgesic effects of opioids are centrally mediated, many of the common side effects are mediated via peripheral receptors. Novel peripheral opioid antagonists have been recently introduced that can block the peripheral actions of opioids without affecting centrally mediated analgesia. We review the clinical and experimental evidence of their efficacy in ameliorating opioid side effects and consider what further information might be useful in defining their role. IMPLICATIONS: The major analgesic effects of opioid medication are mediated within the brain and spinal cord. Many of the side effects of opioids are caused by activation of receptors outside these areas. Recently developed peripherally restricted opioid antagonists have the ability to block many opioid side effects without affecting analgesia.

  3. Potential Clinical Implications of the Urotensin II Receptor Antagonists

    Emilie Kane

    2011-07-01

    Full Text Available Urotensin-II (UII, which binds to its receptor UT, plays an important role in the heart, kidneys, pancreas, adrenal gland and CNS. In the vasculature, it acts as a potent endothelium-independent vasoconstrictor and endothelium-dependent vasodilator. In disease states, this constriction-dilation equilibrium is disrupted. There is an upregulation of the UII system in heart disease, metabolic syndrome and kidney failure. The increase in UII release and UT expression suggest that UII system may be implicated in the pathology and pathogenesis of these diseases by causing an increase in ACAT-1 activity leading to SMC proliferation and foam cell infiltration, insulin resistance (DMII, as well as inflammation, high blood pressure and plaque formation. Recently, UT antagonists such as SB-611812, palosuran, and most recently a piperazino-isoindolinone based antagonist have been developed in the hope of better understanding the UII system and treating its associated diseases.

  4. Alpha particle studies during JET DT experiments

    1999-01-01

    The 1997 DT experiment (DTE1) at the Joint European Torus included studies of the behaviour of alpha particles in high temperature plasmas. Clear alpha particle heating was observed in a series of otherwise similar 10MW hot-ion H-modes by scanning the DT mixture from 0%T to 93%T. Maxima in central temperature and energy content were obtained which corresponded with the maximum in fusion yield. Alfven Eigenmodes (AEs) have been detected in JET, driven by NBI or ICRH fast ions. However, in agreement with theory, no AE activity was observed in DT plasmas which could be attributed to alpha particle drive, except in the afterglow of some Optimised Shear pulses. Ion Cyclotron Emission (ICE) was detected at harmonics of the alpha particle cyclotron frequency at the outer edge of the plasma. The ICE is interpreted as being close to magnetoacoustic cyclotron instability, driven by inverted alpha distributions at the plasma edge. The high-energy neutral particle spectra showed features, which are ascribed to a mixture of alphas, neutralised by helium-like impurities, and deuterons, born from elastic collisions with alpha particles and neutralised by hydrogen-like impurities. The results of all these studies are consistent with classical alpha particle trapping and slowing-down. Future DT experiments will aim to increase alpha particle pressure, so interactions with plasma instabilities can be studied. The measurement of knock-on neutral triton spectra offers a clean way to determine confined alpha densities in these future experiments. (author)

  5. Alpha particle studies during JET DT experiments

    2001-01-01

    The 1997 DT experiment (DTE1) at the Joint European Torus included studies of the behaviour of alpha particles in high temperature plasmas. Clear alpha particle heating was observed in a series of otherwise similar 10MW hot-ion H-modes by scanning the DT mixture from 0%T to 93%T. Maxima in central temperature and energy content were obtained which corresponded with the maximum in fusion yield. Alfven Eigenmodes (AEs) have been detected in JET, driven by NBI or ICRH fast ions. However, in agreement with theory, no AE activity was observed in DT plasmas which could be attributed to alpha particle drive, except in the afterglow of some Optimised Shear pulses. Ion Cyclotron Emission (ICE) was detected at harmonics of the alpha particle cyclotron frequency at the outer edge of the plasma. The ICE is interpreted as being close to magnetoacoustic cyclotron instability, driven by inverted alpha distributions at the plasma edge. The high-energy neutral particle spectra showed features, which are ascribed to a mixture of alphas, neutralised by helium-like impurities, and deuterons, born from elastic collisions with alpha particles and neutralised by hydrogen-like impurities. The results of all these studies are consistent with classical alpha particle trapping and slowing-down. Future DT experiments will aim to increase alpha particle pressure, so interactions with plasma instabilities can be studied. The measurement of knock-on neutral triton spectra offers a clean way to determine confined alpha densities in these future experiments. (author)

  6. Crossing symmetry in Alpha space

    CERN. Geneva

    2017-01-01

    The conformal bootstrap program aims to catalog all conformal field theories (second-order phase transitions) in D dimensions. Despite its ambitious scope much progress has been made over the past decade, e.g. in computing critical exponents for the 3D O(N) models to high precision. At this stage, analytic methods to explore the CFT landscape are not as well developed. In this talk I will describe a new mathematical framework for the bootstrap known as "alpha space", which reduces crossing symmetry to a set of integral equations. Based on arXiv:1702.08471 (with Balt van Rees) and arXiv:1703.08159.

  7. The Alpha Magnetic Spectrometer (AMS)

    Alcaraz, J.; Alpat, B.; Ambrosi, G.; Anderhub, H.; Ao, L.; Arefiev, A.; Azzarello, P.; Babucci, E.; Baldini, L.; Basile, M.; Barancourt, D.; Barao, F.; Barbier, G.; Barreira, G.; Battiston, R.; Becker, R.; Becker, U.; Bellagamba, L.; Bene, P.; Berdugo, J.; Berges, P.; Bertucci, B.; Biland, A.; Bizzaglia, S.; Blasko, S.; Boella, G.; Boschini, M.; Bourquin, M.; Brocco, L.; Bruni, G.; Buenerd, M.; Burger, J.D.; Burger, W.J.; Cai, X.D.; Camps, C.; Cannarsa, P.; Capell, M.; Casadei, D.; Casaus, J.; Castellini, G.; Cecchi, C.; Chang, Y.H.; Chen, H.F.; Chen, H.S.; Chen, Z.G.; Chernoplekov, N.A.; Chiueh, T.H.; Chuang, Y.L.; Cindolo, F.; Commichau, V.; Contin, A.; Crespo, P.; Cristinziani, M.; Cunha, J.P. da; Dai, T.S.; Deus, J.D.; Dinu, N.; Djambazov, L.; DAntone, I.; Dong, Z.R.; Emonet, P.; Engelberg, J.; Eppling, F.J.; Eronen, T.; Esposito, G.; Extermann, P.; Favier, J.; Fiandrini, E.; Fisher, P.H.; Fluegge, G.; Fouque, N.; Galaktionov, Yu.; Gervasi, M.; Giusti, P.; Grandi, D.; Grimm, O.; Gu, W.Q.; Hangarter, K.; Hasan, A.; Hermel, V.; Hofer, H.; Huang, M.A.; Hungerford, W.; Ionica, M.; Ionica, R.; Jongmanns, M.; Karlamaa, K.; Karpinski, W.; Kenney, G.; Kenny, J.; Kim, W.; Klimentov, A.; Kossakowski, R.; Koutsenko, V.; Kraeber, M.; Laborie, G.; Laitinen, T.; Lamanna, G.; Laurenti, G.; Lebedev, A.; Lee, S.C.; Levi, G.; Levtchenko, P.; Liu, C.L.; Liu, H.T.; Lopes, I.; Lu, G.; Lu, Y.S.; Luebelsmeyer, K.; Luckey, D.; Lustermann, W.; Mana, C.; Margotti, A.; Mayet, F.; McNeil, R.R.; Meillon, B.; Menichelli, M.; Mihul, A.; Mourao, A.; Mujunen, A.; Palmonari, F.; Papi, A.; Park, I.H.; Pauluzzi, M.; Pauss, F.; Perrin, E.; Pesci, A.; Pevsner, A.; Pimenta, M.; Plyaskin, V.; Pojidaev, V.; Postolache, V.; Produit, N.; Rancoita, P.G.; Rapin, D.; Raupach, F.; Ren, D.; Ren, Z.; Ribordy, M.; Richeux, J.P.; Riihonen, E.; Ritakari, J.; Roeser, U.; Roissin, C.; Sagdeev, R.; Sartorelli, G.; Schultz von Dratzig, A.; Schwering, G.; Scolieri, G.; Seo, E.S.; Shoutko, V.; Shoumilov, E.; Siedling, R.; Son, D.; Song, T.; Steuer, M.; Sun, G.S.; Suter, H.; Tang, X.W.; Ting, S.C.C.Samuel C.C.; Ting, S.M.; Tornikoski, M.; Torsti, J.; Tr umper, J.; Ulbricht, J.; Urpo, S.; Usoskin, I.; Valtonen, E.; Vandenhirtz, J.; Velcea, F.; Velikhov, E.; Verlaat, B.; Vetlitsky, I.; Vezzu, F.; Vialle, J.P.; Viertel, G.; Vite, D.; Gunten, H. Von; Wicki, S.W.S. Waldmeier; Wallraff, W.; Wang, B.C.; Wang, J.Z.; Wang, Y.H.; Wiik, K.; Williams, C.; Wu, S.X.; Xia, P.C.; Yan, J.L.; Yan, L.G.; Yang, C.G.; Yang, M.; Ye, S.W.; Yeh, P.; Xu, Z.Z.; Zhang, H.Y.; Zhang, Z.P.; Zhao, D.X.; Zhu, G.Y.; Zhu, W.Z.; Zhuang, H.L.; Zichichi, A.; Zimmermann, B.

    2002-01-01

    The Alpha Magnetic Spectrometer (AMS) is a large acceptance (0.65 sr m 2 ) detector designed to operate in the International Space Station (ISS) for three years. The purposes of the experiment are to search for cosmic antimatter and dark matter and to study the composition and energy spectrum of the primary cosmic rays. A 'scaled-down' version has been flown on the Space Shuttle Discovery for 10 days in June 1998. The complete AMS is programmed for installation on the ISS in October 2003 for an operational period of 3 yr. This contribution reports on the experimental configuration that will be installed on the ISS

  8. Construction, purification, and characterization of a chimeric TH1 antagonist

    Javier-González Luís

    2006-05-01

    Full Text Available Abstract Background TH1 immune response antagonism is a desirable approach to mitigate some autoimmune and inflammatory reactions during the course of several diseases where IL-2 and IFN-γ are two central players. Therefore, the neutralization of both cytokines could provide beneficial effects in patients suffering from autoimmune or inflammatory illnesses. Results A chimeric antagonist that can antagonize the action of TH1 immunity mediators, IFN-γ and IL-2, was designed, engineered, expressed in E. coli, purified and evaluated for its in vitro biological activities. The TH1 antagonist molecule consists of the extracellular region for the human IFNγ receptor chain 1 fused by a four-aminoacid linker peptide to human 60 N-terminal aminoacid residues of IL-2. The corresponding gene fragments were isolated by RT-PCR and cloned in the pTPV-1 vector. E. coli (W3110 strain was transformed with this vector. The chimeric protein was expressed at high level as inclusion bodies. The protein was partially purified by pelleting and washing. It was then solubilized with strong denaturant and finally refolded by gel filtration. In vitro biological activity of chimera was demonstrated by inhibition of IFN-γ-dependent HLA-DR expression in Colo 205 cells, inhibition of IFN-γ antiproliferative effect on HEp-2 cells, and by a bidirectional effect in assays for IL-2 T-cell dependent proliferation: agonism in the absence versus inhibition in the presence of IL-2. Conclusion TH1 antagonist is a chimeric protein that inhibits the in vitro biological activities of human IFN-γ, and is a partial agonist/antagonist of human IL-2. With these attributes, the chimera has the potential to offer a new opportunity for the treatment of autoimmune and inflammatory diseases.

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

    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.

  10. Suvorexant: The first orexin receptor antagonist to treat insomnia

    Dubey, Ashok K.; Handu, Shailendra S.; Mediratta, Pramod K.

    2015-01-01

    Primary insomnia is mainly treated with drugs acting on benzodiazepine receptors and a few other classes of drugs used for different co-morbidities. A novel approach to treat insomnia has been introduced recently, with the approval of suvorexant, the first in a new class of orexin receptor antagonists. Orexin receptors in the brain have been found to play an important role in the regulation of various aspects of arousal and motivation. The drugs commonly used for insomnia therapy to date, hav...

  11. A prototypical Sigma-1 receptor antagonist protects against brain ischemia

    Schetz, John A.; Perez, Evelyn; Liu, Ran; Chen, Shiuhwei; Lee, Ivan; Simpkins, James W.

    2007-01-01

    Previous studies indicate that the Sigma-1 ligand 4-phenyl-1-(4-phenylbutyl) piperidine (PPBP) protects the brain from ischemia. Less clear is whether protection is mediated by agonism or antagonism of the Sigma-1 receptor, and whether drugs already in use for other indications and that interact with the Sigma-1 receptor might also prevent oxidative damage due to conditions such as cerebral ischemic stroke. The antipsychotic drug haloperidol is an antagonist of Sigma-1 receptors and in this s...

  12. [Necrotic leg ulcer revealing vasculitis induced by vitamin K antagonists].

    Chabli, H; Hocar, O; Akhdari, N; Amal, S; Hakkou, M; Hamdaoui, A

    2015-12-01

    Vitamin K antagonists are widely used in thromboembolic diseases. Hemorrhagic complications related to drug overdose represent their main side effect. We report a rare side effect, a severe and unexpected type of skin vasculitis - necrotic leg ulcer - induced by vitamin K antagonist. A 63-year-old female with a history of diabetes developed hyperalgesic necrotic ulcerations on the lower limbs one month after starting an acenocoumarol-based treatment for ischemic heart disease. Histological examination revealed lymphocytic vasculitis with fibrinoid necrosis. Etiological explorations searching for vasculitis were negative. In the absence of a precise etiology, drug-induced ulcer was suspected. Low molecular weight heparin was prescribed to replace acenocoumarol. The lesions slowly resolved with topical treatment. The chronological criteria and the negativity of etiological explorations allowed the diagnosis of vitamin K antagonist-induced necrotic skin ulcer. Clinicians should be aware of this rare complication induced by oral anticoagulants because of its practical therapeutic implications. This is the first case of necrotic leg ulcer induced by acenocoumarol corresponding histologically to necrotising lymphocytic vasculitis. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  13. Toxicological Differences Between NMDA Receptor Antagonists and Cholinesterase Inhibitors.

    Shi, Xiaodong; Lin, Xiaotian; Hu, Rui; Sun, Nan; Hao, Jingru; Gao, Can

    2016-08-01

    Cholinesterase inhibitors (ChEIs), represented by donepezil, rivastigmine, and galantamine, used to be the only approved class of drugs for the treatment of Alzheimer's disease. After the approval of memantine by the Food and Drug Administration (FDA), N-methyl-d-aspartic acid (NMDA) receptor antagonists have been recognized by authorities and broadly used in the treatment of Alzheimer's disease. Along with complementary mechanisms of action, NMDA antagonists and ChEIs differ not only in therapeutic effects but also in adverse reactions, which is an important consideration in clinical drug use. And the number of patients using NMDA antagonists and ChEIs concomitantly has increased, making the matter more complicated. Here we used the FDA Adverse Event Reporting System for statistical analysis , in order to compare the adverse events of memantine and ChEIs. In general, the clinical evidence confirmed the safety advantages of memantine over ChEIs, reiterating the precautions of clinical drug use and the future direction of antidementia drug development. © The Author(s) 2016.

  14. Twisted gastrulation, a BMP antagonist, exacerbates podocyte injury.

    Sachiko Yamada

    Full Text Available Podocyte injury is the first step in the progression of glomerulosclerosis. Previous studies have demonstrated the beneficial effect of bone morphogenetic protein 7 (Bmp7 in podocyte injury and the existence of native Bmp signaling in podocytes. Local activity of Bmp7 is controlled by cell-type specific Bmp antagonists, which inhibit the binding of Bmp7 to its receptors. Here we show that the product of Twisted gastrulation (Twsg1, a Bmp antagonist, is the central negative regulator of Bmp function in podocytes and that Twsg1 null mice are resistant to podocyte injury. Twsg1 was the most abundant Bmp antagonist in murine cultured podocytes. The administration of Bmp induced podocyte differentiation through Smad signaling, whereas the simultaneous administration of Twsg1 antagonized the effect. The administration of Bmp also inhibited podocyte proliferation, whereas simultaneous administration of Twsg1 antagonized the effect. Twsg1 was expressed in the glomerular parietal cells (PECs and distal nephron of the healthy kidney, and additionally in damaged glomerular cells in a murine model of podocyte injury. Twsg1 null mice exhibited milder hypoalbuminemia and hyperlipidemia, and milder histological changes while maintaining the expression of podocyte markers during podocyte injury model. Taken together, our results show that Twsg1 plays a critical role in the modulation of protective action of Bmp7 on podocytes, and that inhibition of Twsg1 is a promising means of development of novel treatment for podocyte injury.

  15. Frequent epigenetic inactivation of Wnt antagonist genes in breast cancer

    Suzuki, H; Toyota, M; Caraway, H; Gabrielson, E; Ohmura, T; Fujikane, T; Nishikawa, N; Sogabe, Y; Nojima, M; Sonoda, T; Mori, M; Hirata, K; Imai, K; Shinomura, Y; Baylin, S B; Tokino, T

    2008-01-01

    Although mutation of APC or CTNNB1 (β-catenin) is rare in breast cancer, activation of Wnt signalling is nonetheless thought to play an important role in breast tumorigenesis, and epigenetic silencing of Wnt antagonist genes, including the secreted frizzled-related protein (SFRP) and Dickkopf (DKK) families, has been observed in various tumours. In breast cancer, frequent methylation and silencing of SFRP1 was recently documented; however, altered expression of other Wnt antagonist genes is largely unknown. In the present study, we found frequent methylation of SFRP family genes in breast cancer cell lines (SFRP1, 7 out of 11, 64%; SFRP2, 11 out of 11, 100%; SFRP5, 10 out of 11, 91%) and primary breast tumours (SFRP1, 31 out of 78, 40%; SFRP2, 60 out of 78, 77%; SFRP5, 55 out of 78, 71%). We also observed methylation of DKK1, although less frequently, in cell lines (3 out of 11, 27%) and primary tumours (15 out of 78, 19%). Breast cancer cell lines express various Wnt ligands, and overexpression of SFRPs inhibited cancer cell growth. In addition, overexpression of a β-catenin mutant and depletion of SFRP1 using small interfering RNA synergistically upregulated transcriptional activity of T-cell factor/lymphocyte enhancer factor. Our results confirm the frequent methylation and silencing of Wnt antagonist genes in breast cancer, and suggest that their loss of function contributes to activation of Wnt signalling in breast carcinogenesis. PMID:18283316

  16. A naturally occurring Lgr4 splice variant encodes a soluble antagonist useful for demonstrating the gonadal roles of Lgr4 in mammals.

    Pei-Jen Hsu

    Full Text Available Leucine-rich repeat containing G protein-coupled receptor 4 (LGR4 promotes the Wnt signaling through interaction with R-spondins or norrin. Using PCR amplification from rat ovarian cDNAs, we identified a naturally occurring Lgr4 splice variant encoding only the ectodomain of Lgr4, which was named Lgr4-ED. Lgr4-ED can be detected as a secreted protein in the extracts from rodent and bovine postnatal gonads, suggesting conservation of Lgr4-ED in mammals. Recombinant Lgr4-ED purified from the conditioned media of transfected 293T cells was found to dose-dependently inhibit the LGR4-mediated Wnt signaling induced by RSPO2 or norrin, suggesting that it is capable of ligand absorption and could have a potential role as an antagonist. Intraperitoneal injection of purified recombinant Lgr4-ED into newborn mice was found to significantly decrease the testicular expression of estrogen receptor alpha and aquaporin 1, which is similar to the phenotype found in Lgr4-null mice. Administration of recombinant Lgr4-ED to superovulated female rats can also decrease the expression of estrogen receptor alpha, aquaporin 1, LH receptor and other key steroidogenic genes as well as bring about the suppression of progesterone production. Thus, these findings suggest that endogenously expressed Lgr4-ED may act as an antagonist molecule and help to fine-tune the R-spondin/norrin-mediated Lgr4-Wnt signaling during gonadal development.

  17. Involvement of interleukin 1 and interleukin 1 antagonist in pancreatic beta-cell destruction in insulin-dependent diabetes mellitus

    Mandrup-Poulsen, T; Zumsteg, U; Reimers, J

    1993-01-01

    In this review we propose that the balance between the action of interleukin 1 (IL-1) and its natural antagonist IL-1ra on the level of the insulin-producing pancreatic beta-cell may play a decisive role in the pathogenesis of insulin-dependent diabetes mellitus (IDDM). We argue that IL-1...... potentiated by other cytokines (tumor necrosis factor alpha, interferon gamma) is an important effector molecule involved in both early and late events in the immune-mediated process that leads to beta-cell destruction and IDDM. We also point out that surprisingly high molar excesses of IL-1ra over IL-1...... are necessary to block the action of IL-1 on islet beta-cells compared to islet alpha-cells in vitro and in animals. We suggest that the selectivity of beta-cell destruction in IDDM may be conferred on several levels: (1) homing of beta-cell antigen specific T cells, (2) targeted delivery of cytokines...

  18. Lloviu virus VP24 and VP35 proteins function as innate immune antagonists in human and bat cells

    Feagins, Alicia R.; Basler, Christopher F.

    2015-01-01

    Lloviu virus (LLOV) is a new member of the filovirus family that also includes Ebola virus (EBOV) and Marburg virus (MARV). LLOV has not been cultured; however, its genomic RNA sequence indicates the coding capacity to produce homologs of the EBOV and MARV VP24, VP35, and VP40 proteins. EBOV and MARV VP35 proteins inhibit interferon (IFN)-alpha/beta production and EBOV VP35 blocks activation of the antiviral kinase PKR. The EBOV VP24 and MARV VP40 proteins inhibit IFN signaling, albeit by different mechanisms. Here we demonstrate that LLOV VP35 suppresses Sendai virus induced IFN regulatory factor 3 (IRF3) phosphorylation, IFN-α/β production, and PKR phosphorylation. Additionally, LLOV VP24 blocks tyrosine phosphorylated STAT1 binding to karyopherin alpha 5 (KPNA5), STAT1 nuclear accumulation, and IFN-induced gene expression. LLOV VP40 lacks detectable IFN antagonist function. These activities parallel EBOV IFN inhibitory functions. EBOV and LLOV VP35 and VP24 proteins also inhibit IFN responses in bat cells. These data suggest that LLOV infection will block innate immune responses in a manner similar to EBOV. - Highlights: • Lloviu virus (LLOV) is a new member of the filovirus family. • LLOV VP35 blocks IRF3 phosphorylation, IFN-α/β production and PKR phosphorylation. • LLOV VP24 inhibits IFN responses by targeting phospho-STAT1 KPNA interaction. • Infection by LLOV may block innate immune responses in a manner similar to EBOV.

  19. Lloviu virus VP24 and VP35 proteins function as innate immune antagonists in human and bat cells

    Feagins, Alicia R.; Basler, Christopher F., E-mail: chris.basler@mssm.edu

    2015-11-15

    Lloviu virus (LLOV) is a new member of the filovirus family that also includes Ebola virus (EBOV) and Marburg virus (MARV). LLOV has not been cultured; however, its genomic RNA sequence indicates the coding capacity to produce homologs of the EBOV and MARV VP24, VP35, and VP40 proteins. EBOV and MARV VP35 proteins inhibit interferon (IFN)-alpha/beta production and EBOV VP35 blocks activation of the antiviral kinase PKR. The EBOV VP24 and MARV VP40 proteins inhibit IFN signaling, albeit by different mechanisms. Here we demonstrate that LLOV VP35 suppresses Sendai virus induced IFN regulatory factor 3 (IRF3) phosphorylation, IFN-α/β production, and PKR phosphorylation. Additionally, LLOV VP24 blocks tyrosine phosphorylated STAT1 binding to karyopherin alpha 5 (KPNA5), STAT1 nuclear accumulation, and IFN-induced gene expression. LLOV VP40 lacks detectable IFN antagonist function. These activities parallel EBOV IFN inhibitory functions. EBOV and LLOV VP35 and VP24 proteins also inhibit IFN responses in bat cells. These data suggest that LLOV infection will block innate immune responses in a manner similar to EBOV. - Highlights: • Lloviu virus (LLOV) is a new member of the filovirus family. • LLOV VP35 blocks IRF3 phosphorylation, IFN-α/β production and PKR phosphorylation. • LLOV VP24 inhibits IFN responses by targeting phospho-STAT1 KPNA interaction. • Infection by LLOV may block innate immune responses in a manner similar to EBOV.

  20. Inhibition of A2A Adenosine Receptor Signaling in Cancer Cells Proliferation by the Novel Antagonist TP455

    Stefania Gessi

    2017-12-01

    Full Text Available Several evidences indicate that the ubiquitous nucleoside adenosine, acting through A1, A2A, A2B, and A3 receptor (AR subtypes, plays crucial roles in tumor development. Adenosine has contrasting effects on cell proliferation depending on the engagement of different receptor subtypes in various tumors. The involvement of A2AARs in human A375 melanoma, as well as in human A549 lung and rat MRMT1 breast carcinoma proliferation has been evaluated in view of the availability of a novel A2AAR antagonist, with high affinity and selectivity, named as 2-(2-furanyl-N5-(2-methoxybenzyl[1,3]thiazolo[5,4-d]pyrimidine-5,7-diammine (TP455. Specifically, the signaling pathways triggered in the cancer cells of different origin and the antagonist effect of TP455 were investigated. The A2AAR protein expression was evaluated through receptor binding assays. Furthermore, the effect of A2AAR activation on cell proliferation at 24, 48 and 72 hours was studied. The selective A2AAR agonist 2-p-(2-carboxyethylphenethylamino-5′-N-ethylcarboxamidoadenosine hydrochloride (CGS21680, concentration-dependently induced cell proliferation in A375, A549, and MRMT1 cancer cells and the effect was potently antagonized by the A2AAR antagonist TP455, as well as by the reference A2AAR blocker 4-(2-[7-amino-2-(2-furyl[1,2,4]triazolo[2,3-a][1,3,5]triazin-5-ylamino]ethylphenol (ZM241385. As for the signaling pathway recruited in this response we demonstrated that, by using the specific inhibitors of signal transduction pathways, the effect of A2AAR stimulation was induced through phospholipase C (PLC and protein kinase C-delta (PKC-δ. In addition, we evaluated, through the AlphaScreen SureFire phospho(p protein assay, the kinases enrolled by A2AAR to stimulate cell proliferation and we found the involvement of protein kinase B (AKT, extracellular regulated kinases (ERK1/2, and c-Jun N-terminal kinases (JNKs. Indeed, we demonstrated that the CGS21680 stimulatory effect on kinases was

  1. Microbial Herd Protection Mediated by Antagonistic Interaction in Polymicrobial Communities

    Wong, Megan J. Q.; Liang, Xiaoye; Smart, Matt; Tang, Le; Moore, Richard; Ingalls, Brian

    2016-01-01

    ABSTRACT In host and natural environments, microbes often exist in complex multispecies communities. The molecular mechanisms through which such communities develop and persist, despite significant antagonistic interactions between species, are not well understood. The type VI secretion system (T6SS) is a lethal weapon commonly employed by Gram-negative bacteria to inhibit neighboring species through the delivery of toxic effectors. It is well established that intraspecies protection is conferred by immunity proteins that neutralize effector toxicities. In contrast, the mechanisms for interspecies protection are not clear. Here we use two T6SS-active antagonistic bacterial species, Aeromonas hydrophila and Vibrio cholerae, to demonstrate that interspecies protection is dependent on effectors. A. hydrophila and V. cholerae do not share conserved immunity genes but could coexist equally in a mixture. However, mutants lacking the T6SS or effectors were effectively eliminated by the competing wild-type strain. Time-lapse microscopic analyses showed that mutually lethal interactions drive the segregation of mixed species into distinct single-species clusters by eliminating interspersed single cells. Cluster formation provides herd protection by abolishing lethal interactions inside each cluster and restricting the interactions to the boundary. Using an agent-based modeling approach, we simulated the antagonistic interactions of two hypothetical species. The resulting simulations recapitulated our experimental observations. These results provide mechanistic insights regarding the general role of microbial weapons in determining the structures of complex multispecies communities. IMPORTANCE Investigating the warfare of microbes allows us to better understand the ecological relationships in complex microbial communities such as the human microbiota. Here we use the T6SS, a deadly bacterial weapon, as a model to demonstrate the importance of lethal interactions in

  2. Microbial herd protection mediated by antagonistic interaction in polymicrobial communities.

    Wong, Megan; Liang, Xiaoye; Smart, Matt; Tang, Le; Moore, Richard; Ingalls, Brian; Dong, Tao G

    2016-09-16

    In the host and natural environments, microbes often exist in complex multispecies communities. The molecular mechanisms through which such communities develop and persist - despite significant antagonistic interactions between species - are not well understood. The type VI secretion system (T6SS) is a lethal weapon commonly employed by Gram-negative bacteria to inhibit neighboring species through delivery of toxic effectors. It is well established that intra-species protection is conferred by immunity proteins that neutralize effector toxicities. By contrast, the mechanisms for interspecies protection are not clear. Here we use two T6SS active antagonistic bacteria, Aeromonas hydrophila (AH) and Vibrio cholerae (VC), to demonstrate that interspecies protection is dependent on effectors. AH and VC do not share conserved immunity genes but could equally co-exist in a mixture. However, mutants lacking the T6SS or effectors were effectively eliminated by the other competing wild type. Time-lapse microscopy analyses show that mutually lethal interactions drive the segregation of mixed species into distinct single-species clusters by eliminating interspersed single cells. Cluster formation provides herd protection by abolishing lethal interaction inside each cluster and restricting it to the boundary. Using an agent-based modeling approach, we simulated the antagonistic interactions of two hypothetical species. The resulting simulations recapitulate our experimental observation. These results provide mechanistic insights for the general role of microbial weapons in determining the structures of complex multispecies communities. Investigating the warfare of microbes allows us to better understand the ecological relationships in complex microbial communities such as the human microbiota. Here we use the T6SS, a deadly bacterial weapon, as a model to demonstrate the importance of lethal interactions in determining community structures and exchange of genetic materials

  3. Synthesis and evaluation of new imaging agent for central nicotinic acetylcholine receptor {alpha}{sub 7} subtype

    Ogawa, Mikako [Photon Medical Research Center, Hamamatsu University School of Medicine, Hamamatsu (Japan); Nishiyama, Shingo; Tsukada, Hideo [PET Center, Central Research Laboratory, Hamamatsu Photonics K.K., Hamamatsu (Japan); Hatano, Kentaro [National Institute for Longevity Sciences, National Center for Geriatrics and Gerontology, Obu (Japan); Fuchigami, Takeshi [Photon Medical Research Center, Hamamatsu University School of Medicine, Hamamatsu (Japan); Yamaguchi, Hiroshi [National Institute for Longevity Sciences, National Center for Geriatrics and Gerontology, Obu (Japan); Molecular Imaging Frontier Research Center, Hamamatsu University School of Medicine, Hamamatsu (Japan); Matsushima, Yoshitaka [Department of Chemistry, Hamamatsu University School of Medicine, Hamamatsu (Japan); Ito, Kengo [National Institute for Longevity Sciences, National Center for Geriatrics and Gerontology, Obu (Japan); Magata, Yasuhiro [Photon Medical Research Center, Hamamatsu University School of Medicine, Hamamatsu (Japan); Molecular Imaging Frontier Research Center, Hamamatsu University School of Medicine, Hamamatsu (Japan)], E-mail: magata@hama-med.ac.jp

    2010-04-15

    Introduction: The nicotinic acetylcholine receptor (nAChR) {alpha}7 subtype ({alpha}{sub 7} nAChR) is one of the major nAChR subtypes in the brain. We synthesized C-11 labeled {alpha}{sub 7} nAChR ligands, (R)-2-[{sup 11}C]methylamino-benzoic acid 1-aza-bicyclo[2.2.2]oct-3-yl ester ([{sup 11}C](R)-MeQAA) and its isomer (S)-[{sup 11}C]MeQAA, for in vivo investigation with positron emission tomography (PET). Then, the potential of (R)- and (S)-[{sup 11}C]MeQAA for in vivo imaging of {alpha}{sub 7} nAChR in the brain was evaluated in mice and monkeys. Methods: The binding affinity for {alpha}{sub 7} nAChR was measured using rat brain. Biodistribution and in vivo receptor blocking studies were undertaken in mice. Dynamic PET scans were performed in conscious monkeys. Results: The affinity for {alpha}{sub 7} nAChR was 41 and 182 nM for (R)- and (S)-MeQAA, respectively. The initial uptake in the mouse brain was high ([{sup 11}C](R)-MeQAA: 7.68 and [{sup 11}C](S)-MeQAA: 6.65 %dose/g at 5 min). The clearance of [{sup 11}C](R)-MeQAA was slow in the hippocampus ({alpha}{sub 7} nAChR-rich region) but was rapid in the cerebellum ({alpha}{sub 7} nAChR-poor region). On the other hand, the clearance was fast for [{sup 11}C](S)-MeQAA in all regions. The brain uptake of [{sup 11}C](R)-MeQAA was decreased by methyllycaconitine ({alpha}{sub 7} nAChR antagonist) treatment. In monkeys, {alpha}{sub 7} nAChRs were highly distributed in the thalamus and cortex but poorly distributed in the cerebellum. The high accumulation was observed in the cortex and thalamus for [{sup 11}C](R)-MeQAA, while the uptake was rather homogeneous for [{sup 11}C](S)-MeQAA. Conclusions: [{sup 11}C](R)-MeQAA was successfully synthesized and showed high uptake to the brain. However, since the in vivo selectivity for {alpha}{sub 7} nAChR was not enough, further PET kinetic analysis or structure optimization is needed for specific visualization of brain {alpha}{sub 7} nAChRs in vivo.

  4. Alterations in mGluR5 expression and signaling in Lewy body disease and in transgenic models of alpha-synucleinopathy--implications for excitotoxicity.

    Diana L Price

    2010-11-01

    Full Text Available Dementia with Lewy bodies (DLB and Parkinson's Disease (PD are neurodegenerative disorders of the aging population characterized by the abnormal accumulation of alpha-synuclein (alpha-syn. Previous studies have suggested that excitotoxicity may contribute to neurodegeneration in these disorders, however the underlying mechanisms and their relationship to alpha-syn remain unclear. For this study we proposed that accumulation of alpha-syn might result in alterations in metabotropic glutamate receptors (mGluR, particularly mGluR5 which has been linked to deficits in murine models of PD. In this context, levels of mGluR5 were analyzed in the brains of PD and DLB human cases and alpha-syn transgenic (tg mice and compared to age-matched, unimpaired controls, we report a 40% increase in the levels of mGluR5 and beta-arrestin immunoreactivity in the frontal cortex, hippocampus and putamen in DLB cases and in the putamen in PD cases. In the hippocampus, mGluR5 was more abundant in the CA3 region and co-localized with alpha-syn aggregates. Similarly, in the hippocampus and basal ganglia of alpha-syn tg mice, levels of mGluR5 were increased and mGluR5 and alpha-syn were co-localized and co-immunoprecipitated, suggesting that alpha-syn interferes with mGluR5 trafficking. The increased levels of mGluR5 were accompanied by a concomitant increase in the activation of downstream signaling components including ERK, Elk-1 and CREB. Consistent with the increased accumulation of alpha-syn and alterations in mGluR5 in cognitive- and motor-associated brain regions, these mice displayed impaired performance in the water maze and pole test, these behavioral alterations were reversed with the mGluR5 antagonist, MPEP. Taken together the results from study suggest that mGluR5 may directly interact with alpha-syn resulting in its over activation and that this over activation may contribute to excitotoxic cell death in select neuronal regions. These results highlight the

  5. Beta/alpha continuous air monitor

    Becker, G.K.; Martz, D.E.

    1988-06-27

    A single deep layer silicon detector in combination with a microcomputer, recording both alpha and beta activity and the energy of each pulse, distinquishing energy peaks using a novel curve fitting technique to reduce the natural alpha counts in the energy region where plutonium and other transuranic alpha emitters are present, and using a novel algorithm to strip out radon daughter contribution to actual beta counts. 7 figs.

  6. Targeted alpha therapy: Applications and current status

    Bruchertseifer, Frank

    2017-01-01

    Full text: The field of targeted alpha therapy has been developed rapidly in the last decade. Besides 223 Ra, 211 At and 212 Pb/ 212 Bi the alpha emitters 225 Ac and 213 Bi are promising therapeutic radionuclides for application in targeted alpha therapy of cancer and infectious diseases. The presentation will give a short overview about the current clinical treatments with alpha emitting radionuclides and will place an emphasis on the most promising clinical testing of peptides and antibodies labelled with 225 Ac and 213 Bi for treatment of metastatic castration-resistant prostate cancer patients with glioma and glioblastoma multiform, PSMA-positive tumor phenotype and bladder carcinoma in situ. (author)

  7. Monitor for alpha beta contamination of hands; Moniteur de contamination alpha beta des mains

    Guitton, J

    1958-07-01

    The following specifications of hands alpha beta contamination monitor are presented: the position of the hands, the detection and separation of alpha and beta, the information processing, the programming, the results presentation and general characteristics. (A.L.B.)

  8. Differential involvement of 5-HT(1A) and 5-HT(1B/1D) receptors in human interferon-alpha-induced immobility in the mouse forced swimming test.

    Zhang, Hongmei; Wang, Wei; Jiang, Zhenzhou; Shang, Jing; Zhang, Luyong

    2010-01-01

    Although Interferon-alpha (IFN-alpha, CAS 9008-11-1) is a powerful drug in treating several viral infections and certain tumors, a considerable amount of neuropsychiatric side-effects such as depression and anxiety are an unavoidable consequence. Combination with the selective serotonin (5-HT) reuptake inhibitor (SSRI) fluoxetine (CAS 56296-78-7) significantly improved the situation. However, the potential 5-HT(1A) receptor- and 5-HT(1B) receptor-signals involved in the antidepressant effects are still unclear. The effects of 5-HT(1A) receptor- and 5-HT(1B) receptor signals were analyzed by using the mouse forced swimming test (FST), a predictive test of antidepressant-like action. The present results indicated that (1) fluoxetine (administrated intragastrically, 30 mg/kg; not subactive dose: 15 mg/kg) significantly reduced IFN-alpha-induced increase of the immobility time in the forced swimming test; (2) 5-HT(1A) receptor- and 5-HT(1B) receptor ligands alone or in combination had no effects on IFN-alpha-induced increase of the immobility time in the FST; (3) surprisingly, WAY 100635 (5-HT(1A) receptor antagonist, 634908-75-1) and 8-OH-DPAT(5-HT(1A) receptor agonist, CAS 78950-78-4) markedly enhanced the antidepressant effect of fluoxetine at the subactive dose (15 mg/kg, i. g.) on the IFN-alpha-treated mice in the FST. Further investigations showed that fluoxetine combined with WAY 100635 and 8-OH-DPAT failed to produce antidepressant effects in the FST. (4) Co-application of CGS 12066A (5-HT(1B) receptor agonist, CAS 109028-09-3) or GR 127935 (5-HT(1B/1D) receptor antagonist, CAS 148642-42-6) with fluoxetine had no synergistic effects on the IFN-alpha-induced increase of immobility time in FST. (5) Interestingly, co-administration of GR 127935, WAY 100635 and fluoxetine significantly reduced the IFN-alpha-induced increase in immobility time of FST, being more effective than co-administration of WAY 100635 and fluoxetine. All results suggest that (1) compared to

  9. An immunocapture/scintillation proximity analysis of G alpha q/11 activation by native serotonin (5-HT)2A receptors in rat cortex: blockade by clozapine and mirtazapine.

    Mannoury La Cour, C; Chaput, C; Touzard, M; Millan, M J

    2009-02-01

    Though transduction mechanisms recruited by heterologously expressed 5-HT(2A) receptors have been extensively studied, their interaction with specific subtypes of G-protein remains to be directly evaluated in cerebral tissue. Herein, as shown by an immunocapture/scintillation proximity analysis, 5-HT, the prototypical 5-HT(2A) agonist, DOI, and Ro60,0175 all enhanced [(35)S]GTPgammaS binding to G alpha q/11 in rat cortex with pEC(50) values of 6.22, 7.24 and 6.35, respectively. No activation of G o or G s/olf was seen at equivalent concentrations of DOI. Stimulation of G alpha q/11 by 5-HT (30 microM) and DOI (30 microM) was abolished by the selective 5-HT(2A) vs. 5-HT(2C)/5-HT(2B) antagonists, ketanserin (pK(B) values of 9.11 and 8.88, respectively) and MDL100,907 (9.82 and 9.68). By contrast, 5-HT-induced [(35)S]GTPgammaS binding to G alpha q/11 was only weakly inhibited by the preferential 5-HT(2C) receptor antagonists, RS102,221 (6.94) and SB242,084 (7.39), and the preferential 5-HT(2B) receptor antagonist, LY266,097 (6.66). The antipsychotic, clozapine, which had marked affinity for 5-HT(2A) receptors, blocked the recruitment of G alpha q/11 by 5-HT and DOI with pK(B) values of 8.54 and 8.14, respectively. Its actions were mimicked by the "atypical" antidepressant and 5-HT(2A) receptor antagonist, mirtazapine, which likewise blocked 5-HT and DOI-induced G alpha q/11 protein activation with pK(B) values of 7.90 and 7.76, respectively. In conclusion, by use of an immunocapture/scintillation proximity strategy, this study shows that native 5-HT(2A) receptors in rat frontal cortex specifically recruit G alpha q/11 and that this action is blocked by clozapine and mirtazapine. Quantification of 5-HT(2A) receptor-mediated G alpha q/11 activation in frontal cortex should prove instructive in characterizing the actions of diverse classes of psychotropic agent. 2008 Wiley-Liss, Inc.

  10. Pharmacological treatment of the benign prostatic hyperplasia; Tratamiento farmacologico en la hiperplasia prostatica benigna

    Perez Guerra, Yohani; Molina Cuevas, Vivian; Oyarzabal Yera, Ambar; Mas Ferreiro, Rosa, E-mail: yohani.perez@cnic.edu.c [Centro de Productos Naturales, Centro Nacional de Investigaciones Cientificas (CNIC), La Habana (Cuba)

    2011-07-01

    Benign prostatic hyperplasia is a common disease in over 50 years-old men consisting in uncontrolled and benign growth of prostatic gland that leads to lower urinary tract symptoms. The etiology of benign prostatic hyperplasia is multifactoral involving the increased conversion of testosterone in dihydrotestosterone by the prostatic 5{alpha}-reductase action, which brought about events that encourage the prostate growth (static component) and the increase of the bladder and prostate smooth muscle tone (dynamic component) regulated by the a{alpha}{sub 1} -adrenoceptors (ADR). The pharmacological treatment of the benign prostatic hyperplasia includes the prostatic 5a{alpha}-reductase inhibitors, the a{alpha}{sub 1}-adrenoreceptor blockers, their combined therapy and the phytotherapy. This paper was aimed at presenting the most relevant aspects of the pharmacology of drugs used for treating the benign prostatic hyperplasia, and providing elements to analyze their efficacy, safety and tolerability. To this end, a review was made of the different drugs for the treatment of this pathology and they were grouped according to their mechanism of action. Natural products were included as lipid extracts from Serenoa repens and Pygeum africanum as well as D-004, a lipid extract from Roystonea regia fruits, with proved beneficial effects on the main etiological factors of benign prostatic hyperplasia. D-004 is a prostatic 5a-reductase inhibitor, an a{alpha}{sub 1}-adrenoceptor antagonist, a{alpha} 5-lipooxygenase inhibitor and has antioxidant action, all of which reveals a multifactoral mechanism. The results achieved till now indicate that D-004 is a safe and well-tolerated product

  11. Hypothalamic PGC-1 alpha Protects Against High-Fat Diet Exposure by Regulating ER alpha

    Morselli, Eugenia; Fuente-Martin, Esther; Finan, Brian; Kim, Min; Frank, Aaron; Garcia-Caceres, Cristina; Navas, Carlos Rodriguez; Gordillo, Ruth; Neinast, Michael; Kalainayakan, Sarada P.; Li, Dan L.; Gao, Yuanqing; Yi, Chun-Xia; Hahner, Lisa; Palmer, Biff F.; Tschöp, Matthias H.; Clegg, Deborah J.

    2014-01-01

    High-fat diets (HFDs) lead to obesity and inflammation in the central nervous system (CNS). Estrogens and estrogen receptor alpha (ER alpha) protect premenopausal females from the metabolic complications of inflammation and obesity-related disease. Here, we demonstrate that hypothalamic PGC-1 alpha

  12. Resting-State Alpha in Autism Spectrum Disorder and Alpha Associations with Thalamic Volume

    Edgar, J. Christopher; Heiken, Kory; Chen, Yu-Han; Herrington, John D.; Chow, Vivian; Liu, Song; Bloy, Luke; Huang, Mingxiong; Pandey, Juhi; Cannon, Katelyn M.; Qasmieh, Saba; Levy, Susan E.; Schultz, Robert T.; Roberts, Timothy P. L.

    2015-01-01

    Alpha circuits (8-12 Hz), necessary for basic and complex brain processes, are abnormal in autism spectrum disorder (ASD). The present study obtained estimates of resting-state (RS) alpha activity in children with ASD and examined associations between alpha activity, age, and clinical symptoms. Given that the thalamus modulates cortical RS alpha…

  13. Does protein binding modulate the effect of angiotensin II receptor antagonists?

    Marc P Maillard

    2001-03-01

    Full Text Available IntroductionAngiotensin II AT 1-receptor antagonists are highly bound to plasma proteins (≥ 99%. With some antagonists, such as DuP-532, the protein binding was such that no efficacy of the drug could be demonstrated clinically. Whether protein binding interferes with the efficacy of other antagonists is not known. We have therefore investigated in vitro how plasma proteins may affect the antagonistic effect of different AT1-receptor antagonists.MethodsA radio-receptor binding assay was used to analyse the interaction between proteins and the ability of various angiotensin II (Ang II antagonists to block AT1-receptors. In addition, the Biacore technology, a new technique which enables the real-time monitoring of binding events between two molecules, was used to evaluate the dissociation rate constants of five AT1-receptor antagonists from human serum albumin.ResultsThe in vitro AT 1-antagonistic effects of different Ang II receptor antagonists were differentially affected by the presence of human plasma, with rightward shifts of the IC50 ranging from one to several orders of magnitude. The importance of the shift correlates with the dissociation rate constants of these drugs from albumin. Our experiments also show that the way that AT1-receptor antagonists bind to proteins differs from one compound to another. These results suggest that the interaction with plasma proteins appears to modulate the efficacy of some Ang II antagonists.ConclusionAlthough the high binding level of Ang II receptor antagonist to plasma proteins appears to be a feature common to this class of compounds, the kinetics and characteristics of this binding is of great importance. With some antagonists, protein binding interferes markedly with their efficacy to block AT1-receptors.

  14. Sexually antagonistic "zygotic drive" of the sex chromosomes.

    William R Rice

    2008-12-01

    Full Text Available Genomic conflict is perplexing because it causes the fitness of a species to decline rather than improve. Many diverse forms of genomic conflict have been identified, but this extant tally may be incomplete. Here, we show that the unusual characteristics of the sex chromosomes can, in principle, lead to a previously unappreciated form of sexual genomic conflict. The phenomenon occurs because there is selection in the heterogametic sex for sex-linked mutations that harm the sex of offspring that does not carry them, whenever there is competition among siblings. This harmful phenotype can be expressed as an antagonistic green-beard effect that is mediated by epigenetic parental effects, parental investment, and/or interactions among siblings. We call this form of genomic conflict sexually antagonistic "zygotic drive", because it is functionally equivalent to meiotic drive, except that it operates during the zygotic and postzygotic stages of the life cycle rather than the meiotic and gametic stages. A combination of mathematical modeling and a survey of empirical studies is used to show that sexually antagonistic zygotic drive is feasible, likely to be widespread in nature, and that it can promote a genetic "arms race" between the homo- and heteromorphic sex chromosomes. This new category of genomic conflict has the potential to strongly influence other fundamental evolutionary processes, such as speciation and the degeneration of the Y and W sex chromosomes. It also fosters a new genetic hypothesis for the evolution of enigmatic fitness-reducing traits like the high frequency of spontaneous abortion, sterility, and homosexuality observed in humans.

  15. Central actions of a novel and selective dopamine antagonist

    Schulz, D.W.

    1985-01-01

    Receptors for the neurotransmitter dopamine traditionally have been divided into two subgroups: the D 1 class, which is linked to the stimulation of adenylate cyclase-activity, and the D 2 class which is not. There is much evidence suggesting that it is the D 2 class which is not. There is much evidence suggesting that it is the D 2 dopamine receptor that mediates the physiological and behavioral actions of dopamine in the intact animal. However, the benzazepine SCH23390 is a dopamine antagonist which has potent behavioral actions while displaying apparent neurochemical selectivity for the D 1 class of dopamine receptors. The purpose of this dissertation was to (1) confirm and characterize this selectivity, and (2) test certain hypothesis related to possible modes of action of SCH233390. The inhibition of adenylate cyclase by SCH23390 occurred via an action at the dopamine receptor only. A radiolabeled analog of SCH23390 displayed the receptor binding properties of a specific high-affinity ligand, and regional receptor densities were highly correlated with dopamine levels. The subcellular distribution of [ 3 H]-SCH23390 binding did not correspond completely with that of dopamine-stimulated adenylate cyclase. The neurochemical potency of SCH23390 as a D 1 receptor antagonist was preserved following parental administration. A variety of dopamine agonists and antagonists displayed a high correlation between their abilities to compete for [ 3 H]-SCH23390 binding in vitro and to act at an adenylate cyclase-linked receptor. Finally, the relative affinities of dopamine and SCH23390 for both D 1 receptors and [ 3 H]-SCH23390 binding sites were comparable. It is concluded that the behavioral effects of SCH23390 are mediated by actions at D 1 dopamine receptors only, and that the physiological importance of this class of receptors should be reevaluated

  16. Modulation of myometrium mitochondrial membrane potential by calmodulin antagonists

    S. G. Shlykov

    2014-02-01

    Full Text Available Influence of calmodulin antagonists on mitochondrial membrane potential was investigated using­ a flow cytometry method, confocal microscopy and fluorescent potential-sensitive probes TMRM and MTG. Influence of different concentrations of calmodulin antagonists on mitochondrial membrane potential was studied using flow cytometry method and a fraction of myometrium mitochondria of unpregnant rats. It was shown that 1-10 µМ calmidazolium gradually reduced mitochondria membrane potential. At the same time 10-100 µМ trifluope­razine influenced as follows: 10 µМ – increased polarization, while 100 µМ – caused almost complete depolarization of mitochondrial membranes. In experiments which were conducted with the use of confocal microscopy method and myometrium cells it was shown, that MTG addition to the incubation medium­ led to the appearance of fluorescence signal in a green range. Addition of the second probe (ТМRM resulted in the appearance of fluorescent signal in a red range. Mitochondrial membrane depolarization by 1µМ СССР or 10 mМ NaN3 was accompanied by the decline of “red” fluo­rescence intensity, “green” fluorescence was kept. The 10-15 minute incubation of myometrium cells in the presen­ce 10 µМ calmidazolium or 100 µМ trifluoperazine was accompanied by almost complete decrease of the TMRM fluorescent signal. Thus, with the use of potential-sensitive fluorescent probes TMRM and MTG it was shown, that calmodulin antagonists modulate mitochondrial membrane potential of myometrium cells.

  17. Bayesian Meta-Analysis of Coefficient Alpha

    Brannick, Michael T.; Zhang, Nanhua

    2013-01-01

    The current paper describes and illustrates a Bayesian approach to the meta-analysis of coefficient alpha. Alpha is the most commonly used estimate of the reliability or consistency (freedom from measurement error) for educational and psychological measures. The conventional approach to meta-analysis uses inverse variance weights to combine…

  18. DT results of TFTR's alpha collector

    Herrmann, H.W.; Zweben, S.J.; Darrow, D.S.; Timberlake, J.R.; Macaulay-Newcombe, R.G.

    1996-01-01

    An escaping alpha collector probe has been developed for TFTR's DT phase to complement the results of the lost alpha scintillator detectors which have been operating on TFTR since 1988. Measurements of the energy distribution of escaping alphas have been made by measuring the range of alphas implanted into nickel foils located within the alpha collector. Exposed samples have been analyzed for 4 DT plasma discharges at plasma currents of 1.0 and 1.8 MA. The results at 1.0 MA are in good agreement with predictions for first orbit alpha loss at 3.5 MeV. The 1.8 MA results, however, indicate a large anomalous loss of partially thermalized alphas at an energy ∼30% below the birth energy and at a total fluence nearly an order of magnitude above expected first orbit loss. This anomalous loss is not observed with the lost alpha scintillator detectors in DT plasmas but does resemble the anomalous delayed loss seen in DD plasmas. Several potential explanations for this loss process are examined. None of the candidate explanations proposed thus far are fully consistent with the anomalous loss observations

  19. Psychiatric Symptoms in Alpha-Mannosidosis

    Malm, D.; Pantel, J.; Linaker, O. M.

    2005-01-01

    Alpha-mannosidosis is characterized by mild to moderate intellectual disability (ID), moderate to severe neurosensory hearing loss, frequent infections, psychomotor disturbances and skeletal dysmorphism. For the first time, a panel of nine alpha-mannosidosis patients with psychiatric symptoms is presented. The clinical picture has several…

  20. ALPHA experiment facility and Prof. Jeffrey Hangst.

    Maximilien Brice

    2010-01-01

    Picture 01-07: General views of the ALPHA experiment Picture 5: Andrea Gutierrez, a PhD student from UBC, transfers liquid helium from a storage dewar into the cryostat containing the superconducting magnetic trap used by the ALPHA experiment.Picture 08-11: Jeffery Hangst, spokesperson for ALPHA Picture 12: The ALPHA silicon detector, which surrounds the trapping resion and is used for imaging antiproton annihilations (Credit University of Liverpool) Picture 13: Untrapped antihydrogen atoms annihilating on the inner surface of the ALPHA trap. These are measured by the ALPHA annihilation detector. The events are concentrated at the electrode radius of about 22.3 mm. The coordinates are defined in the Nature article, Figure 1b. Picture 14: The electrodes (gold) for the ALPHA Penning trap being inserted into the vacuum chamber and cryostat assembly. This is the trap used to combine or "mix" positrons and antiprotons to make antihydrogen. (Credit: Niels Madsen ALPHA/Swansea.) Picture 15: Top, a diagram of the...

  1. Meta-Analysis of Coefficient Alpha

    Rodriguez, Michael C.; Maeda, Yukiko

    2006-01-01

    The meta-analysis of coefficient alpha across many studies is becoming more common in psychology by a methodology labeled reliability generalization. Existing reliability generalization studies have not used the sampling distribution of coefficient alpha for precision weighting and other common meta-analytic procedures. A framework is provided for…

  2. The ALPHA detector : Module Production and Assembly

    Andresen, G; Bowe, P D; Cesar, C L; Chapman, S; Charlton, M; Fajans, J; Fujiwara, M C; Gill, D R; Hangst, J S; Hydomako, R; Jenkins, M J; Kurchaninov, L; Madsen, N; Nolan, P; Olchanski, K; Olin, A; Povilus, A; Robicheaux, F; Sarid, E; Silveira, D M; Storey, J W; Thompson, R I; van der Werf, D P; Wurtele, J S; Yamazaki, Y; Ashkezari, M D; Baquero-Ruiz, M; Butler, E; Deller, A; Eriksson, S; Friesen, T; Gutierrez, A; Hardy, W N; Hayden, M E; Humphries, A J; Jonsell, S; McKenna, J T K; Menary, S; Pusa, P; Sampson, J; Seddon, D; Seif el Nasr, S; So, C; Thornhill, J; Wells, D; Jorgensen, L V

    2012-01-01

    ALPHA is one of the experiments situated at CERN's Antiproton Decelerator (AD). A Silicon Vertex Detector (SVD) is placed to surround the ALPHA atom trap. The main purpose of the SVD is to detect and locate antiproton annihilation events by means of the emitted charged pions. The SVD system is presented with special focus given to the design, fabrication and performance of the modules.

  3. Alpha and fission autoradiography of uranium rods

    Copic, M.; Ilicj, R.; Najzher, M.; Rant, J.

    1977-01-01

    Macro and micro-distribution of uranium minerals in ore bodies are investigated by alpha autoradiography and by neutron induced fission autoradiography using LR 115 solid state track detector. Optimal conditions are determined experimentally for both methods and examples presented. For field applications the alpha autoradiography (author)

  4. Alpha-1 Antitrypsin Deficiency (Inherited Emphysema)

    ... antitrypsin inactivates elastase once it has finished its job. Without alpha 1 antitrypsin, elastase can destroy the air sacs of the lung. How is the diagnosis made? Because Alpha-1 related disease is COPD, the diagnosis is made by the same methods. Your doctor may have you do a number ...

  5. Exhaustive Weakly Wandering Sequences and Alpha-type Transformations

    Stanley Eigen

    2015-12-01

    Full Text Available An increasing sequence of integers, $\\mathbb{B}$, is given for which there exists a family of ergodic, infinite measure preserving transformations $T_\\alpha$, $0 \\leq \\alpha \\leq 1$ so that (1 $T_\\alpha$ is of $\\alpha$-type and (2 $\\mathbb{B}$ is an exhaustive weakly wandering sequence for each $T_\\alpha$.

  6. Membrane formation in liquids by adding an antagonistic salt

    Sadakane, Koichiro; Seto, Hideki

    2018-03-01

    Antagonistic salts are composed of hydrophilic and hydrophobic ions. In a binary mixture, such as water and organic solvent, these ion pairs preferentially dissolve to those phases, respectively, and there is a coupling between the charge density and the composition. The heterogeneous distribution of ions forms a large electric double layer at the interface between these solvents. This reduces the interfacial tension between water and organic solvent, and stabilizes an ordered structure, such as a membrane. These phenomena have been extensively studied from both theoretical and experimental point of view. In addition, the numerical simulations can reproduce such ordered structures.

  7. Effect of a Hypocretin/Orexin Antagonist on Neurocogniive Performance

    2014-09-01

    time: Tuesday , Nov 12, 2013, 4:00 PM - 5:00 PM Topic: ++E.08.e Sleep: Systems and behavior Authors: W. LINCOLN1, J. PALMERSTON1, T. NEYLAN2, T...functional impairment results from HcrtR antagonist-induced sleep, we evaluated the performance of rats in the Morris Water Maze in the presence of ALM vs. ZOL... Morris Water Maze. Although the concentrations of ALM and ZOL adminis- tered prior to these tests were equipotent in hypnotic efficacy, the

  8. Membrane Formation in Liquids by Adding an Antagonistic Salt

    Koichiro Sadakane

    2018-03-01

    Full Text Available Antagonistic salts are composed of hydrophilic and hydrophobic ions. In a binary mixture, such as water and organic solvent, these ion pairs preferentially dissolve to those phases, respectively, and there is a coupling between the charge density and the composition. The heterogeneous distribution of ions forms a large electric double layer at the interface between these solvents. This reduces the interfacial tension between water and organic solvent, and stabilizes an ordered structure, such as a membrane. These phenomena have been extensively studied from both theoretical and experimental point of view. In addition, the numerical simulations can reproduce such ordered structures.

  9. The discovery of tropane-derived CCR5 receptor antagonists.

    Armour, Duncan R; de Groot, Marcel J; Price, David A; Stammen, Blanda L C; Wood, Anthony; Perros, Manos; Burt, Catherine

    2006-04-01

    The development of compound 1, a piperidine-based CCR5 receptor antagonist with Type I CYP2D6 inhibition, into the tropane-derived analogue 5, is described. This compound, which is devoid of CYP2D6 liabilities, is a highly potent ligand for the CCR5 receptor and has broad-spectrum activity against a range of clinically relevant HIV isolates. The identification of human ether a-go-go-related gene channel inhibition within this series is described and the potential for QTc interval prolongation discussed. Furthermore, structure activity relationship (SAR) around the piperidine moiety is also described.

  10. The opiate antagonist, naltrexone, in the treatment of trichotillomania

    Grant, Jon E; Odlaug, Brian Lawrence; Schreiber, Liana R N

    2014-01-01

    Trichotillomania (TTM) is characterized by repetitive hair pulling resulting in hair loss. Data on the pharmacological treatment of TTM are limited. This study examined the opioid antagonist, naltrexone, in adults with TTM who had urges to pull their hair. Fifty-one individuals with TTM were...... randomized to naltrexone or placebo in an 8-week, double-blind trial. Subjects were assessed with measures of TTM severity and selected cognitive tasks. Naltrexone failed to demonstrate significantly greater reductions in hair pulling compared to placebo. Cognitive flexibility, however, significantly...

  11. Long-range alpha detector (LRAD)

    MacArthur, D.W.; McAtee, J.L.

    1991-01-01

    Historically, alpha detectors have been limited by the very short range of alpha particles in air and by relatively poor sensitivity, even if the particles are intercepted. Of necessity, these detectors are operated in a vacuum or in close proximity to the source if reasonable efficiency is desired. In our new long-range alpha detector (LRAD), alpha particles interact with the ambient air, producing ionization in the air at the rate of about 30,000 ion pairs per MeV of alpha energy. These charges can be transported over significant distances (several meters) in a moving current of air generated by a small fan. An ion chamber located in front of the fan measures the current carried by the moving ions. The LRAD-based monitor is more sensitive and more thorough than conventional monitors. We present current LRAD sensitivity limits and results, practical monitor designs, and proposed uses for LRAD monitors. 4 refs., 7 figs

  12. Technical Basis for the Use of Alpha Absorption Corrections on RCF Gross Alpha Data

    Ceffalo, G.M.

    1999-01-01

    This document provides the supporting data and rationale for making absorption corrections to gross alpha data to correct alpha data for loss due to absorption in the sample matrix. For some time there has been concern that the gross alpha data produced by the Environmental Restoration Contractor Radiological Counting Facility, particularly gross alpha analysis on soils, has been biased toward low results, as no correction for self-absorption was applied to the counting data. The process was investigated, and a new methodology for alpha self-absorption has been developed

  13. The tree-alpha Faddeev calculation on 12C bound states with a Pauli correct alpha-alpha potential

    Kamada, Hiroyuki; Oryu, Shinsho

    1986-01-01

    The three-alpha model of 12 C is investigated by the Faddeev formalism with the UIM alpha-alpha potential, in which the Pauli effect between two-alpha system was taken into account adequately. The potential can reproduce the on- and off-shell effects of the alpha-alpha interaction by the rank-4 separable type for the S-wave, the rank-3 one for the D-wave, and the rank-2 one for the G-wave, in which two of the ranks in the S-wave, and one in the D-wave are prepared to eliminate the Pauli forbidden states. We obtained three even states J π = 0 + , 2 + , 4 + , and two odd states 1 - , 3 - , below the alpha- 8 Be(0 + g.s) threshold energy. The even parity states gain larger binding energies than those which have been obtained by former Faddeev calculation with the rank-1 Kukulin and Neudatchin (KN) potential. On the other hand, for the odd parity states, we obtained smaller binding energies than the former one. It is found that our Faddeev calculation with the UIM potential does not miss any important low-lying levels of 12 C, in which any spurious states do not appear. (author)

  14. Genetic Evidence for an Interferon-Antagonistic Function of Rift Valley Fever Virus Nonstructural Protein NSs

    Bouloy, Michèle; Janzen, Christian; Vialat, Pierre; Khun, Huot; Pavlovic, Jovan; Huerre, Michel; Haller, Otto

    2001-01-01

    Rift Valley fever virus (RVFV), a phlebovirus of the family Bunyaviridae, is a major public health threat in Egypt and sub-Saharan Africa. The viral and host cellular factors that contribute to RVFV virulence and pathogenicity are still poorly understood. All pathogenic RVFV strains direct the synthesis of a nonstructural phosphoprotein (NSs) that is encoded by the smallest (S) segment of the tripartite genome and has an undefined accessory function. In this report, we show that MP12 and clone 13, two attenuated RVFV strains with mutations in the NSs gene, were highly virulent in IFNAR−/− mice lacking the alpha/beta interferon (IFN-α/β) receptor but remained attenuated in IFN-γ receptor-deficient mice. Both attenuated strains proved to be excellent inducers of early IFN-α/β production. In contrast, the virulent strain ZH548 failed to induce detectable amounts of IFN-α/β and replicated extensively in both IFN-competent and IFN-deficient mice. Clone 13 has a defective NSs gene with a large in-frame deletion. This defect in the NSs gene results in expression of a truncated protein which is rapidly degraded. To investigate whether the presence of the wild-type NSs gene correlated with inhibition of IFN-α/β production, we infected susceptible IFNAR−/− mice with S gene reassortant viruses. When the S segment of ZH548 was replaced by that of clone 13, the resulting reassortants became strong IFN inducers. When the defective S segment of clone 13 was exchanged with the wild-type S segment of ZH548, the reassortant virus lost the capacity to stimulate IFN-α/β production. These results demonstrate that the ability of RVFV to inhibit IFN-α/β production correlates with viral virulence and suggest that the accessory protein NSs is an IFN antagonist. PMID:11152510

  15. Suppression of ERβ signaling via ERβ knockout or antagonist protects against bladder cancer development.

    Hsu, Iawen; Chuang, Kun-Lung; Slavin, Spencer; Da, Jun; Lim, Wei-Xun; Pang, See-Tong; O'Brien, Jeanne H; Yeh, Shuyuan

    2014-03-01

    Epidemiological studies showed that women have a lower bladder cancer (BCa) incidence, yet higher muscle-invasive rates than men, suggesting that estrogen and the estrogen receptors, estrogen receptor alpha (ERα) and estrogen receptor beta (ERβ), may play critical roles in BCa progression. Using in vitro cell lines and an in vivo carcinogen N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN)-induced mouse BCa model, we found that ERβ plays a positive role in promoting BCa progression. Knockdown of ERβ with ERβ-shRNA in ERβ-positive human BCa J82, 647v and T24 cell lines led to suppressed cell growth and invasion. Mice lacking ERβ have less cancer incidence with reduced expression of the proliferation marker Ki67 in BBN-induced BCa. Consistently, our results show that non-malignant urothelial cells with ERβ knockdown are more resistant to carcinogen-induced malignant transformation. Mechanism dissection found that targeting ERβ suppressed the expression of minichromosome maintenance complex component 5 (MCM5), a DNA replication licensing factor that is involved in tumor cell growth. Restoring MCM5 expression can partially reverse ERβ knockdown-mediated growth reduction. Supportively, treating cells with the ERβ-specific antagonist, 4-[2-Phenyl-5,7-bis(trifluoromethyl) pyrazolo[1,5-a]pyrimidin-3-yl]phenol (PHTPP), reduced BCa cell growth and invasion, as well as MCM5 expression. Furthermore, we provide the first evidence that BCa burden and mortality can be controlled by PHTPP treatment in the carcinogen-induced BCa model. Together, these results demonstrate that ERβ could play positive roles in promoting BCa progression via MCM5 regulation. Targeting ERβ through ERβ-shRNA, PHTPP or via downstream targets, such as MCM5, could serve as potential therapeutic approaches to battle BCa.

  16. Alpha1 and Alpha2 Integrins Mediate Invasive Activity of Mouse Mammary Carcinoma Cells through Regulation of Stromelysin-1 Expression

    Lochter, Andre; Navre, Marc; Werb, Zena; Bissell, Mina J

    1998-06-29

    Tumor cell invasion relies on cell migration and extracellular matrix proteolysis. We investigated the contribution of different integrins to the invasive activity of mouse mammary carcinoma cells. Antibodies against integrin subunits {alpha}6 and {beta}1, but not against {alpha}1 and {alpha}2, inhibited cell locomotion on a reconstituted basement membrane in two-dimensional cell migration assays, whereas antibodies against {beta}1, but not against a6 or {alpha}2, interfered with cell adhesion to basement membrane constituents. Blocking antibodies against {alpha}1 integrins impaired only cell adhesion to type IV collagen. Antibodies against {alpha}1, {alpha}2, {alpha}6, and {beta}1, but not {alpha}5, integrin subunits reduced invasion of a reconstituted basement membrane. Integrins {alpha}1 and {alpha}2, which contributed only marginally to motility and adhesion, regulated proteinase production. Antibodies against {alpha}1 and {alpha}2, but not {alpha}6 and {beta}1, integrin subunits inhibited both transcription and protein expression of the matrix metalloproteinase stromelysin-1. Inhibition of tumor cell invasion by antibodies against {alpha}1 and {alpha}2 was reversed by addition of recombinant stromelysin-1. In contrast, stromelysin-1 could not rescue invasion inhibited by anti-{alpha}6 antibodies. Our data indicate that {alpha}1 and {alpha}2 integrins confer invasive behavior by regulating stromelysin-1 expression, whereas {alpha}6 integrins regulate cell motility. These results provide new insights into the specific functions of integrins during tumor cell invasion.

  17. The role of ecology, neutral processes and antagonistic coevolution in an apparent sexual arms race.

    Perry, Jennifer C; Garroway, Colin J; Rowe, Locke

    2017-09-01

    Some of the strongest examples of a sexual 'arms race' come from observations of correlated evolution in sexually antagonistic traits among populations. However, it remains unclear whether these cases truly represent sexually antagonistic coevolution; alternatively, ecological or neutral processes might also drive correlated evolution. To investigate these alternatives, we evaluated the contributions of intersex genetic correlations, ecological context, neutral genetic divergence and sexual coevolution in the correlated evolution of antagonistic traits among populations of Gerris incognitus water striders. We could not detect intersex genetic correlations for these sexually antagonistic traits. Ecological variation was related to population variation in the key female antagonistic trait (spine length, a defence against males), as well as body size. Nevertheless, population covariation between sexually antagonistic traits remained substantial and significant even after accounting for all of these processes. Our results therefore provide strong evidence for a contemporary sexual arms race. © 2017 John Wiley & Sons Ltd/CNRS.

  18. Novel quinolinone-phosphonic acid AMPA antagonists devoid of nephrotoxicity.

    Cordi, Alex A; Desos, Patrice; Ruano, Elisabeth; Al-Badri, Hashim; Fugier, Claude; Chapman, Astrid G; Meldrum, Brian S; Thomas, Jean-Yves; Roger, Anita; Lestage, Pierre

    2002-10-01

    We reported previously the synthesis and structure-activity relationships (SAR) in a series of 2-(1H)-oxoquinolines bearing different acidic functions in the 3-position. Exploiting these SAR, we were able to identify 6,7-dichloro-2-(1H)-oxoquinoline-3-phosphonic acid compound 3 (S 17625) as a potent, in vivo active AMPA antagonist. Unfortunately, during the course of the development, nephrotoxicity was manifest at therapeutically effective doses. Considering that some similitude exists between S 17625 and probenecid, a compound known to protect against the nephrotoxicity and/or slow the clearance of different drugs, we decided to synthesise some new analogues of S 17625 incorporating some of the salient features of probenecid. Replacement of the chlorine in position 6 by a sulfonylamine led to very potent AMPA antagonists endowed with good in vivo activity and lacking nephrotoxicity potential. Amongst the compounds evaluated, derivatives 7a and 7s appear to be the most promising and are currently evaluated in therapeutically relevant stroke models.

  19. Modification of kindled amygdaloid seizures by opiate agonists and antagonists.

    Albertson, T E; Joy, R M; Stark, L G

    1984-03-01

    The effects of 19 opiate agonists and antagonists on kindled amygdaloid seizures in the rat were studied. The mu agonists tended to reduce the length of elicited afterdischarges and behavioral ranks, while markedly increasing postictal electroencephalogram spikes and behavioral arrest time. These effects were reversed by naloxone. The kappa agonists reduced behavioral rank and variably reduced afterdischarge length with a concomitant lengthening of postictal behavioral arrest time and number of electroencephalogram spikes. The putative sigma agonist, SKF 10,047, reduced afterdischarge durations only at the higher doses tested. The decreases found after the sigma agonists in postictal electroencephalogram spiking and time of behavioral arrest were not reversed by naloxone. Only the lower doses of normeperidine were found to decrease seizure thresholds. The mixed agonist/antagonists (MAA) cyclazocine and cyclorphan markedly increased seizure threshold and reduced afterdischarge duration and behavioral rank. Only the MAA pentazocine tended to increase threshold but not suprathreshold afterdischarge durations. The order of ability to modify the ictal events was MAA (selected) greater than kappa agonists greater than mu agonists greater than sigma agonists. The increase in postictal events (behavior arrest and spikes) was caused most effectively by pretreatment with mu agonist greater than kappa agonist greater than selected MAA greater than sigma agonists.(ABSTRACT TRUNCATED AT 250 WORDS)

  20. Picrotoxin-induced seizures modified by morphine and opiate antagonists.

    Thomas, J; Nores, W L; Kenigs, V; Olson, G A; Olson, R D

    1993-07-01

    The effects of naloxone, Tyr-MIF-1, and MIF-1 on morphine-mediated changes in susceptibility to picrotoxin-induced seizures were studied. Rats were pretreated with naloxone, MIF-1, Tyr-MIF-1, or saline. At 15-min intervals, they received a second pretreatment of morphine or saline and then were tested for seizures following a convulsant dose of picrotoxin. Several parameters of specific categories of seizures were scored. Morphine increased the number of focal seizure episodes, duration of postseizure akinesis, and incidence of generalized clonic seizures. Naloxone tended to block the morphine-mediated changes in susceptibility. Tyr-MIF-1 had effects similar to naloxone on duration of postseizure immobility but tended to potentiate the effects of morphine on focal seizure episodes. The effects of morphine and the opiate antagonists on focal seizure episodes and postseizure duration suggest the general involvement of several types of opiate receptors in these picrotoxin-induced behaviors. However, the observation of antagonistic effects for Tyr-MIF-1 on immobility but agonistic effects for focal seizures suggests that the type of effect exerted by opiate agents may depend upon other neuronal variables.

  1. Evodiamine as a novel antagonist of aryl hydrocarbon receptor

    Yu, Hui; Tu, Yongjiu; Zhang, Chun; Fan, Xia; Wang, Xi; Wang, Zhanli; Liang, Huaping

    2010-01-01

    Research highlights: → Evodiamine interacted with the AhR. → Evodiamine inhibited the specific binding of [ 3 H]-TCDD to the AhR. → Evodiamine acts as an antagonist of the AhR. -- Abstract: Evodiamine, the major bioactive alkaloid isolated from Wu-Chu-Yu, has been shown to interact with a wide variety of proteins and modify their expression and activities. In this study, we investigated the interaction between evodiamine and the aryl hydrocarbon receptor (AhR). Molecular modeling results revealed that evodiamine directly interacted with the AhR. Cytosolic receptor binding assay also provided the evidence that evodiamine could interact with the AhR with the K i value of 28.4 ± 4.9 nM. In addition, we observed that evodiamine suppressed the 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) induced nuclear translocation of the AhR and the expression of CYP1A1 dose-dependently. These results suggested that evodiamine was able to bind to the AhR as ligand and exhibit antagonistic effects.

  2. Rogue sperm indicate sexually antagonistic coevolution in nematodes.

    Ronald E Ellis

    2014-07-01

    Full Text Available Intense reproductive competition often continues long after animals finish mating. In many species, sperm from one male compete with those from others to find and fertilize oocytes. Since this competition occurs inside the female reproductive tract, she often influences the outcome through physical or chemical factors, leading to cryptic female choice. Finally, traits that help males compete with each other are sometimes harmful to females, and female countermeasures may thwart the interests of males, which can lead to an arms race between the sexes known as sexually antagonistic coevolution. New studies from Caenorhabditis nematodes suggest that males compete with each other by producing sperm that migrate aggressively and that these sperm may be more likely to win access to oocytes. However, one byproduct of this competition appears to be an increased probability that these sperm will go astray, invading the ovary, prematurely activating oocytes, and sometimes crossing basement membranes and leaving the gonad altogether. These harmful effects are sometimes observed in crosses between animals of the same species but are most easily detected in interspecies crosses, leading to dramatically lowered fitness, presumably because the competitiveness of the sperm and the associated female countermeasures are not precisely matched. This mismatch is most obvious in crosses involving individuals from androdioecious species (which have both hermaphrodites and males, as predicted by the lower levels of sperm competition these species experience. These results suggest a striking example of sexually antagonistic coevolution and dramatically expand the value of nematodes as a laboratory system for studying postcopulatory interactions.

  3. Fires can benefit plants by disrupting antagonistic interactions.

    García, Y; Castellanos, M C; Pausas, J G

    2016-12-01

    Fire has a key role in the ecology and evolution of many ecosystems, yet its effects on plant-insect interactions are poorly understood. Because interacting species are likely to respond to fire differently, disruptions of the interactions are expected. We hypothesized that plants that regenerate after fire can benefit through the disruption of their antagonistic interactions. We expected stronger effects on interactions with specialist predators than with generalists. We studied two interactions between two Mediterranean plants (Ulex parviflorus, Asphodelus ramosus) and their specialist seed predators after large wildfires. In A. ramosus we also studied the generalist herbivores. We sampled the interactions in burned and adjacent unburned areas during 2 years by estimating seed predation, number of herbivores and fruit set. To assess the effect of the distance to unburned vegetation we sampled plots at two distance classes from the fire perimeter. Even 3 years after the fires, Ulex plants experienced lower seed damage by specialists in burned sites. The presence of herbivores on Asphodelus decreased in burned locations, and the variability in their presence was significantly related to fruit set. Generalist herbivores were unaffected. We show that plants can benefit from fire through the disruption of their antagonistic interactions with specialist seed predators for at least a few years. In environments with a long fire history, this effect might be one additional mechanism underlying the success of fire-adapted plants.

  4. Pregnancy outcome of “delayed start” GnRH antagonist protocol versus GnRH antagonist protocol in poor responders: A clinical trial study

    Abbas Aflatoonian

    2017-08-01

    Full Text Available Background: Management of poor-responding patients is still major challenge in assisted reproductive techniques (ART. Delayed-start GnRH antagonist protocol is recommended to these patients, but little is known in this regards. Objective: The goal of this study was assessment of delayed-start GnRH antagonist protocol in poor responders, and in vitro fertilization (IVF outcomes. Materials and Methods: This randomized clinical trial included sixty infertile women with Bologna criteria for ovarian poor responders who were candidate for IVF. In case group (n=30, delayed-start GnRH antagonist protocol administered estrogen priming followed by early follicular-phase GnRH antagonist treatment for 7 days before ovarian stimulation with gonadotropin. Control group (n=30 treated with estrogen priming antagonist protocol. Finally, endometrial thickness, the rates of oocytes maturation, , embryo formation, and pregnancy were compared between two groups. Results: Rates of implantation, chemical, clinical, and ongoing pregnancy in delayed-start cycles were higher although was not statistically significant. Endometrial thickness was significantly higher in case group. There were no statistically significant differences in the rates of oocyte maturation, embryo formation, and IVF outcomes between two groups. Conclusion: There is no significant difference between delayed-start GnRH antagonist protocol versus GnRH antagonist protocol.

  5. Increased virulence and competitive advantage of a/alpha over a/a or alpha/alpha offspring conserves the mating system of Candida albicans.

    Lockhart, Shawn R; Wu, Wei; Radke, Joshua B; Zhao, Rui; Soll, David R

    2005-04-01

    The majority of Candida albicans strains in nature are a/alpha and must undergo homozygosis to a/a or alpha/alpha to mate. Here we have used a mouse model for systemic infection to test the hypothesis that a/alpha strains predominate in nature because they have a competitive advantage over a/a and alpha/alpha offspring in colonizing hosts. Single-strain injection experiments revealed that a/alpha strains were far more virulent than either their a/a or alpha/alpha offspring. When equal numbers of parent a/alpha and offspring a/a or alpha/alpha cells were co-injected, a/alpha always exhibited a competitive advantage at the time of extreme host morbidity or death. When equal numbers of an engineered a/a/alpha2 strain and its isogenic a/a parent strain were co-injected, the a/a/alpha2 strain exhibited a competitive advantage at the time of host morbidity or death, suggesting that the genotype of the mating-type (MTL) locus, not associated genes on chromosome 5, provides a competitive advantage. We therefore propose that heterozygosity at the MTL locus not only represses white-opaque switching and genes involved in the mating process, but also affects virulence, providing a competitive advantage to the a/alpha genotype that conserves the mating system of C. albicans in nature.

  6. Diagnostics for PLX-alpha

    Gilmore, Mark; Hsu, Scott

    2015-11-01

    The goal of the Plasma Liner eXperiment PLX-alpha at Los Alamos National Laboratory is to establish the viability of creating a spherically imploding plasma liner for MIF and HED applications, using a spherical array of supersonic plasma jets launched by innovative contoured-gap coaxial plasma guns. PLX- α experiments will focus in particular on establishing the ram pressure and uniformity scalings of partial and fully spherical plasma liners. In order to characterize these parameters experimentally, a suite of diagnostics is planned, including multi-camera fast imaging, a 16-channel visible interferometer (upgraded from 8 channels) with reconfigurable, fiber-coupled front end, and visible and VUV high-resolution and survey spectroscopy. Tomographic reconstruction and data fusion techniques will be used in conjunction with interferometry, imaging, and synthetic diagnostics from modeling to characterize liner uniformity in 3D. Diagnostic and data analysis design, implementation, and status will be presented. Supported by the Advanced Research Projects Agency - Energy - U.S. Department of Energy.

  7. Naturally-occurring alpha activity

    Mayneord, W V

    1960-12-01

    In view of the difficulties of assessing the significance of man-made radioactivity it is important to study for comparison the background of natural radioactivity against which the human race has evolved and lives. It is also important to define the present levels of activity so that it will be possible to detect and study as quickly as possible any changes which may occur owing to the release into the environment of new radioactive materials. Moreover, by the study of the behaviour of natural radioactivity light may be shed upon that of the artificially produced isotopes and a number of analogies traced between the two groups. These concepts have led to studies of naturally-occurring radioactive materials alongside a programme of research into fission products in food, water and air, as well as studies of the metabolism of both sets of materials in the human body. Since the last report there has been a useful increase in our knowledge of natural radioactivity in the biosphere, and its levels relative to the new man-made activities. These studies have necessitated technical developments, particularly in the methods of measuring and identifying alpha-ray emitters, to which group many of the more important natural radioactive materials belong.

  8. Alpha intrusion on ovenight polysomnogram

    Nahapetian R

    2014-06-01

    Full Text Available No abstract available. Article truncated after 150 words. A 30 year-old Army veteran with a past medical history significant for chronic lumbar back pain stemming from a fall-from-height injury sustained in 2006 was referred to the sleep laboratory for evaluation of chronic fatigue and excessive daytime hypersomnolence. His Epworth sleepiness scale score was 16. He denied a history of snoring and witnessed apnea. Body Mass Index (BMI was 25.7 kg/m2. His main sleep related complaints were frequent nocturnal arousals, poor sleep quality, un-refreshing sleep, prolonged latency to sleep onset, and nightmares. An In-lab attended diagnostic polysomnogram was performed. Sleep efficiency was reduced (73% and overall arousal index was not significantly elevated (3.2 events/hour. The sleep study showed rapid eye movement (REM related sleep disordered breathing that did not meet diagnostic criteria for sleep apnea. There was no evidence for period limb movement disorder. However, the study was significant for alpha wave intrusion in stage N2 non-REM and stage ...

  9. Integrated minicomputer alpha analysis system

    Vasilik, D.G.; Coy, D.E.; Seamons, M.; Henderson, R.W.; Romero, L.L.; Thomson, D.A.

    1978-01-01

    Approximately 1,000 stack and occupation air samples from plutonium and uranium facilities at LASL are analyzed daily. The concentrations of radio-nuclides in air are determined by measuring absolute alpha activities of particulates collected on air sample filter media. The Integrated Minicomputer Pulse system (IMPULSE) is an interface between many detectors of extremely simple design and a Digital Equipment Corporation (DEC) PDP-11/04 minicomputer. The detectors are photomultiplier tubes faced with zinc sulfide (ZnS). The average detector background is approximately 0.07 cpm. The IMPULSE system includes two mainframes, each of which can hold up to 64 detectors. The current hardware configuration includes 64 detectors in one mainframe and 40 detectors in the other. Each mainframe contains a minicomputer with 28K words of Random Access Memory. One minicomputer controls the detectors in both mainframes. A second computer was added for fail-safe redundancy and to support other laboratory computer requirements. The main minicomputer includes a dual floppy disk system and a dual DEC 'RK05' disk system for mass storage. The RK05 facilitates report generation and trend analysis. The IMPULSE hardware provides for passage of data from the detectors to the computer, and for passage of status and control information from the computer to the detector stations

  10. Applying alpha-channeling to mirror machines

    Zhmoginov, A. I.; Fisch, N. J. [Department of Astrophysical Sciences, Princeton University, Princeton, New Jersey 08544 (United States)

    2012-05-15

    The {alpha}-channeling effect entails the use of radio-frequency waves to expel and cool high-energetic {alpha} particles born in a fusion reactor; the device reactivity can then be increased even further by redirecting the extracted energy to fuel ions. Originally proposed for tokamaks, this technique has also been shown to benefit open-ended fusion devices. Here, the fundamental theory and practical aspects of {alpha} channeling in mirror machines are reviewed, including the influence of magnetic field inhomogeneity and the effect of a finite wave region on the {alpha}-channeling mechanism. For practical implementation of the {alpha}-channeling effect in mirror geometry, suitable contained weakly damped modes are identified. In addition, the parameter space of candidate waves for implementing the {alpha}-channeling effect can be significantly extended through the introduction of a suitable minority ion species that has the catalytic effect of moderating the transfer of power from the {alpha}-channeling wave to the fuel ions.

  11. Effects of alpha particles on zebrafish embryos

    Yum, E.H.W.; Choi, V.W.Y.; Yu, K.N.; Li, V.W.T.; Cheng, S.H.

    2008-01-01

    Full text: Ionizing radiation such as X-ray and alpha particles can damage cellular macromolecules, which can lead to DNA single- and double-strand breaks. In the present work, we studied the effects of alpha particles on dechorionated zebrafish embryos. Thin polyallyldiglycol carbonate (PADC) films with a thickness of 16 μm were prepared from commercially available PADC films (with thickness of 100 μm) by chemical etching and used as support substrates for holding zebrafish embryos for alpha-particle irradiation. These films recorded alpha-particle hit positions, quantified the number and energy of alpha particles actually incident on the embryo cells, and thus enabled the calculation of the dose absorbed by the embryo cells. Irradiation was made at 1.25 hours post fertilization (hpf) with various absorbed dose. TdT-mediated dUTP Nick-End Labeling (TUNEL) assay was performed on the embryos at different time stages after irradiation. Marked apoptosis was detected only in embryos at earlier time stages. The results showed that DNA double-strand break during zebrafish embryogenesis can be induced by alpha-particle irradiation, which suggests that zebrafish is a potential model for assessing the effects of alpha-particle radiation

  12. Cortical Alpha Activity in Schizoaffective Patients.

    Moeini, Mahdi; Khaleghi, Ali; Mohammadi, Mohammad Reza; Zarafshan, Hadi; Fazio, Rachel L; Majidi, Hamid

    2017-01-01

    Objective: Electrophysiological studies have identified abnormal oscillatory activities in the cerebral cortex in schizophrenia and mood disorders. Biological and pathophysiological evidence suggests specific deficits in serotonin (5-HT) receptor function in schizoaffective disorder (SA), a clinical syndrome with characteristics of both schizophrenia and bipolar disorder. This study investigated alpha oscillations in patients with SA. Method: Electroencephalography was used to measure ongoing and evoked alpha oscillations in 38 adults meeting Diagnostic and Statistical Manual of Mental Disorders-Fourth Edition (DSM-IV) criteria for SA, and in 39 healthy controls. Results: Spontaneous alpha power of the participants with SA was significantly lower than that of healthy participants [F (1, 75) = 8.81, P < 0.01]. Evoked alpha activity was also decreased in SA compared to controls [F (1, 75) = 5.67, P = 0.025]. Conclusion : A strong reduction of alpha power in the posterior regions may reflect abnormality in the thalamocortical circuits. It is shown that hypoxia and reduced cerebral blood flow is associated with reduced alpha activity among different regions of the brain. Therefore, it can be concluded that greatly decreased alpha activity, particularly in centro-parietal and occipital regions, is related to SA symptoms such as hallucinations.

  13. Role of Peripheral Alpha2 Adrenergic Receptors in Tonic Pain During Different Stages of Estrous Cycle in Rats

    AR Abyazi Shelmani

    2007-12-01

    Full Text Available Introduction: Estrogen and progesterone are supposed to modify pain sensitivity. However, the actual role of each of these steroid hormones in this respect is not well known. Plasma concentrations of these hormones show variation during estrous cycle. The role of alpha2 receptors in tonic pain has been pointed out. The aim of the present study was to investigate the agonist and antagonist effect of alpha2 adrenergic receptors on tonic pain sensitivity during all stages of estrous cycle in female rats. Methods: Xylasine as alpha2 agonist and yohimbin as alpha2 antagonist were used via intraperitoneal route (IP. Adult rats weighing 180-200 grams were used. Animals were maintained on 12h reverse light/dark cycle for 7 days prior to the experiment. Water and food was available ad libitum. Formalin test was performed by subcutaneous injection of 50 l formalin (2.5% solution into the hind paw. Formalin test was performed in all stages of estrous cycle for 60 minutes. Animals were divided into four groups; 1- control group (intact animal, 2- Sham group (animals received 0.2 ml normal saline by IP route, 3- Agonist groups (animals received 0.2 ml xylasine 1, 3 mg/kg body weight by IP route and 4- Antagonist group (animals received 0.2 ml yohimbine 1, 3 mg/kg body weight by IP route. Data were statistically analyzed using 2 way ANOVA test followed by Tukey's test as post-hoc test. P<0.05 was considered significant. Results: Results showed that xylasine significantly (p<0.05 decreases pain sensitivity in all stages of estrous cycle. Analgesic effect of xylasine was maximum in estrus stage of estrous cycle and minimum in metestrus stage of estrous cycle. Yohimbine significantly (p<0.05 increases pain sensitivity in all stages of estrous cycle. Hyperalgesic effect of yohimbine was maximum in metestrus stage of estrous cycle and minimum in estrus stage of estrous cycle. Conclusion: These results indicate that alpha2 adrenergic system and endogenous

  14. TNF-{alpha} mediates the stimulation of sclerostin expression in an estrogen-deficient condition

    Kim, Beom-Jun [Division of Endocrinology and Metabolism, Asan Medical Center, University of Ulsan College of Medicine, 388-1 Poongnap2-Dong, Seoul (Korea, Republic of); Bae, Sung Jin [Health Promotion Center, Asan Medical Center, University of Ulsan College of Medicine, 388-1 Poongnap2-Dong, Seoul (Korea, Republic of); Lee, Sun-Young; Lee, Young-Sun; Baek, Ji-Eun; Park, Sook-Young [Asan Institute for Life Sciences, 388-1 Poongnap2-Dong, Seoul (Korea, Republic of); Lee, Seung Hun [Division of Endocrinology and Metabolism, Asan Medical Center, University of Ulsan College of Medicine, 388-1 Poongnap2-Dong, Seoul (Korea, Republic of); Koh, Jung-Min, E-mail: jmkoh@amc.seoul.kr [Division of Endocrinology and Metabolism, Asan Medical Center, University of Ulsan College of Medicine, 388-1 Poongnap2-Dong, Seoul (Korea, Republic of); Kim, Ghi Su [Division of Endocrinology and Metabolism, Asan Medical Center, University of Ulsan College of Medicine, 388-1 Poongnap2-Dong, Seoul (Korea, Republic of)

    2012-07-20

    Highlights: Black-Right-Pointing-Pointer Estrogen deprivation stimulates the bony sclerostin levels with reversal by estrogen. Black-Right-Pointing-Pointer TNF-{alpha} increases the activity and expression of MEF2 in UMR-106 cells. Black-Right-Pointing-Pointer TNF-{alpha} blocker prevents the stimulation of bony sclerostin expression by ovariectomy. Black-Right-Pointing-Pointer No difference in bony sclerostin expression between sham-operated and ovariectomized nude mice. -- Abstract: Although recent clinical studies have suggested a possible role for sclerostin, a secreted Wnt antagonist, in the pathogenesis of postmenopausal osteoporosis, the detailed mechanisms how estrogen deficiency regulates sclerostin expression have not been well-elucidated. Bilateral ovariectomy or a sham operation in female C57BL/6 mice and BALB/c nude mice was performed when they were seven weeks of age. The C57BL/6 mice were intraperitoneally injected with phosphate-buffered serum (PBS), 5 {mu}g/kg {beta}-estradiol five times per week for three weeks, or 10 mg/kg TNF-{alpha} blocker three times per week for three weeks. Bony sclerostin expression was assessed by immunohistochemistry staining in their femurs. The activity and expression of myocyte enhancer factors 2 (MEF2), which is essential for the transcriptional activation of sclerostin, in rat UMR-106 osteosarcoma cells were determined by luciferase reporter assay and western blot analysis, respectively. Bony sclerostin expression was stimulated by estrogen deficiency and it was reversed by estradiol supplementation. When the UMR-106 cells were treated with well-known, estrogen-regulated cytokines, only TNF-{alpha}, but not IL-1 and IL-6, increased the MEF2 activity. Consistently, TNF-{alpha} also increased the nuclear MEF2 expression. Furthermore, the TNF-{alpha} blocker prevented the stimulation of bony sclerostin expression by ovariectomy. We also found that there was no difference in sclerostin expression between ovariectomized

  15. The Cultivation of Antagonistic Bacteria in Irradiated Sludge for Biological Control of Soft Rot Erwinias : Screening of Antagonistic Bacteria for biological Control of Soft Rot Erwinias

    Sermkiattipong, Ng.; Sangsuk, L; Rattanapiriyakul, P; Dejsirilert, S.; Thaveechai, N.

    1998-01-01

    Pure cultures of 57 bacterial isolates for antagonistic activity screening were isolated from three areas of soft rot infested vegetable soil and 58 isolates were obtained from commercial seed compost and seed compost product of Division of Soil and Water Conservation, Department of Land Development. A total of 115 bacterial isolates were evaluated for antagonizing activity against Erwinia carotovora subsp. atroceptica in vitro. Out of them, 18 isolates were antagonists by showing zone of inhibition ranging from 1 to 17 mm by diameter. Most of antagonistic bacteria were identified as Bacillus spp. whereas only one isolate was Pseudomonas vesicularis

  16. Remote Optical Detection of Alpha Radiation

    Sand, J.; Hannuksela, V.; Toivonen, J.; Ihantola, S.; Peraejaervi, K.; Toivonen, H.

    2010-01-01

    Alpha emitting radiation sources are typically hard to detect with conventional detectors due to the short range of alpha particles in the air. However, previous studies have shown that remote detection of alpha radiation is possible by measuring the ionization-induced fluorescence of air molecules. The alpha-induced ultraviolet (UV) light is mainly emitted by molecular nitrogen and its fluorescence properties are well known. The benefit of this method is the long range of UV photons in the air. Secondly, the detection is possible also under a strong beta and gamma radiation backgrounds as they do not cause localized molecular excitation. In this work, the optical detection was studied using two different detection schemes; spectral separation of fluorescence from the background lighting and coincidence detection of UV photons originating from a single radiative decay event. Our spectrally integrated measurements have shown that one alpha decay event yields up to 400 fluorescence photons in the air and all these UV photons are induced in a 5 ns time-window. On the other hand, the probability of a background coincidence event in 5 ns scale is very rare compared to the number of background photons. This information can be applied in fluorescence coincidence filtering to discriminate the alpha radiation initiated fluorescence signal from much more intense background lighting. A device called HAUVA (Handheld Alpha UV Application) was built during this work for demonstration purposes. HAUVA utilizes spectral filtering and it is designed to detect alpha emitters from a distance of about 40 cm. Using specially selected room lighting, the device is able to separate 1 kBq alpha emitter from the background lighting with 1 second integration time. (author)

  17. Steroid withdrawal in the mouse results in anxiogenic effects of 3alpha,5beta-THP: a possible model of premenstrual dysphoric disorder.

    Smith, Sheryl S; Ruderman, Yevgeniy; Frye, Cheryl; Homanics, Gregg; Yuan, Maoli

    2006-06-01

    3alpha-OH-5alpha[beta]-pregnan-20-one (THP) is a positive modulator of the GABAA receptor (GABAR), which underlies its reported anxiolytic effect. However, there are conditions such as premenstrual dysphoric disorder (PMDD) where increases in THP levels can be associated with adverse mood. In order to test for conditions where THP might be anxiogenic, we developed a mouse model of THP withdrawal. Because delta-containing GABAR are highly sensitive to THP modulation, results were compared in wild-type and delta knockout mice. Finasteride, a 5alpha-reductase blocker, was administered for 3 days to female wild-type or delta knockout mice. Then, animals were tested in the elevated plus maze, following acute administration of THP, lorazepam, flumazenil, or 4,5,6,7-tetrahydroisoxazolo[5,4-c]pyridin-3-ol (THIP), and results compared to vehicle-injected controls. CA1 hippocampal GABAR alpha4 subunit levels were assessed by Western blot. After THP withdrawal, THP produced anxiogenic effects, decreasing open arm entries on the elevated plus maze, following a brief shock, in contrast to its expected anxiolytic effects. As we have shown in rats, THP withdrawal also resulted in increased expression of the alpha4 subunit in mouse CA1 hippocampus. As expected for increases in alpha4-containing GABAR, THP withdrawn mice were relatively insensitive to the benzodiazepine (BDZ) lorazepam and had atypical responses to the BDZ antagonist flumazenil when tested on the plus maze. In contrast, they showed a greater anxiolytic response to THIP, which has greater efficacy at alpha4betadelta than other GABAR. Although THP withdrawal in delta knockout mice also increased the alpha4 GABAR subunit, the anxiogenic effects of THP and the anxiolytic effects of THIP were not observed, implicating alpha4betadelta GABAR in these effects. Based on these behavioral and pharmacological findings, we suggest that THP withdrawal in the mouse may serve as a rodent model of PMDD.

  18. Variable displacement alpha-type Stirling engine

    Homutescu, V. M.; Bălănescu, D. T.; Panaite, C. E.; Atanasiu, M. V.

    2016-08-01

    The basic design and construction of an alpha-type Stirling engine with on load variable displacement is presented. The variable displacement is obtained through a planar quadrilateral linkage with one on load movable ground link. The physico-mathematical model used for analyzing the variable displacement alpha-type Stirling engine behavior is an isothermal model that takes into account the real movement of the pistons. Performances and power adjustment capabilities of such alpha-type Stirling engine are calculated and analyzed. An exemplification through the use of the numerical simulation was performed in this regard.

  19. First Attempts at Antihydrogen Trapping in ALPHA

    Andresen, G B; Bowe, P D; Bray, C C; Butler, E; Cesar, C L; Chapman, S; Charlton, M; Fajans, J; Funakoshi, R; Gill, D R; Hangst, J S; Hardy, W N; Hayano, R S; Hayden, M E; Humphries, A J; Hydomako, R; Jenkins, M J; Jørgensen, L V; Kurchaninov, L; Lambo, R; Madsen, N; Nolan, P; Olchanski, K; Olin, A; Page, R D; Povilus, A; Pusa, P; Robicheaux, F; Sarid, E; Seif El Nasr, S; Silveira, D M; Storey, J W; Thompson, R I; Van der Werf, D P; Wasilenko, L; Wurtele, J S; Yamazaki, Y; Fujiwara, M C

    2008-01-01

    We discuss aspects of antihydrogen studies, that relate to particle physics ideas and techniques, within the context of the ALPHA experiment at CERN's Antiproton Decelerator facility. We review the fundamental physics motivations for antihydrogen studies, and their potential physics reach. We argue that initial spectroscopy measurements, once antihydrogen is trapped, could provide competitive tests of CPT, possibly probing physics at the Planck Scale. We discuss some of the particle detection techniques used in ALPHA. Preliminary results from commissioning studies of a partial system of the ALPHA Si vertex detector are presented, the results of which highlight the power of annihilation vertex detection capability in antihydrogen studies.

  20. Alpha spectral analysis via artificial neural networks

    Kangas, L.J.; Hashem, S.; Keller, P.E.; Kouzes, R.T.; Troyer, G.L.

    1994-10-01

    An artificial neural network system that assigns quality factors to alpha particle energy spectra is discussed. The alpha energy spectra are used to detect plutonium contamination in the work environment. The quality factors represent the levels of spectral degradation caused by miscalibration and foreign matter affecting the instruments. A set of spectra was labeled with a quality factor by an expert and used in training the artificial neural network expert system. The investigation shows that the expert knowledge of alpha spectra quality factors can be transferred to an ANN system

  1. Anomalous atomic volume of alpha-Pu

    Kollar, J.; Vitos, Levente; Skriver, Hans Lomholt

    1997-01-01

    We have performed full charge-density calculations for the equilibrium atomic volumes of the alpha-phase light actinide metals using the local density approximation (LDA) and the generalized gradient approximation (GGA). The average deviation between the experimental and the GGA atomic radii is 1.......3%. The comparison between the LDA and GGA results show that the anomalously large atomic volume of alpha-Pu relative to alpha-Np can be ascribed to exchange-correlation effects connected with the presence of low coordinated sites in the structure where the f electrons are close to the onset of localization...

  2. Stochastic interaction between TAE and alpha particles

    Krlin, L.; Pavlo, P.; Malijevsky, I.

    1996-01-01

    The interaction of toroidicity-induced Alfven eigenmodes with thermonuclear alpha particles in the intrinsic stochasticity regime was investigated based on the numerical integration of the equation of motion of alpha particles in the tokamak. The first results obtained for the ITER parameters and moderate wave amplitudes indicate that the stochasticity is highest in the trapped/passing boundary region, where the alpha particles jump stochastically between the two regimes with an appreciable radial excursion (about 0.5 m amplitudes). A similar chaotic behavior was also found for substantially lower energies (about 350 keV). 7 figs., 15 refs

  3. A Quantitative Electrochemiluminescence Assay for Clostridium perfringens alpha toxin

    Merrill, Gerald A; Rivera, Victor R; Neal, Dwayne D; Young, Charles; Poli, Mark A

    2006-01-01

    .... Biotinylated antibodies to C. perfringens alpha toxin bound to streptavidin paramagnetic beads specifically immunoadsorbed soluble sample alpha toxin which subsequently selectively immunoadsorbed ruthenium (Ru...

  4. Imidazoline2 (I2) receptor- and alpha2-adrenoceptor-mediated modulation of hypothalamic-pituitary-adrenal axis activity in control and acute restraint stressed rats.

    Finn, David P; Hudson, Alan L; Kinoshita, Hiroshi; Coventry, Toni L; Jessop, David S; Nutt, David J; Harbuz, Michael S

    2004-03-01

    Central noradrenaline regulates the activity of the hypothalamic-pituitary-adrenal (HPA) axis and the neuroendocrine response to stress. alpha2-adrenoceptors and imidazoline2 (I2) receptors modulate the activity of the central noradrenergic system. The present set of experiments investigated the role of alpha2-adrenoceptors and I2 receptors in the regulation of HPA axis activity under basal conditions and during exposure to the acute psychological stress of restraint. Three separate experiments were carried out in which rats were given an i.p. injection of either saline vehicle, the combined alpha2-adrenoceptor antagonist and I2 receptor ligand idazoxan (10 mg/kg), the selective I2 receptor ligand BU224 (2.5 or 10 mg/kg) or the selective alpha2-adrenoceptor antagonist RX821002 (2.5 mg/kg) with or without restraint stress. Drugs were administered immediately prior to restraint of 60 min duration. Blood was sampled pre-injection, 30, 60 and 240 min post-injection and plasma corticosterone was measured by radioimmunoassay. In experiment 1, idazoxan increased plasma corticosterone levels in naive animals and potentiated the corticosterone response to acute restraint stress. In experiment 2, BU224 administration increased plasma corticosterone levels in a dose-related manner in naive rats. The results of experiment 3 indicated that RX821002 also elevated plasma corticosterone levels in naive rats, however, only BU224 potentiated the corticosterone response to restraint stress. These studies suggest that both alpha2-adrenoceptors and I2 receptors play a role in modulating basal HPA axis activity and that I2 receptors may play a more important role than alpha2-adrenoceptors in modulating the HPA axis response to the acute psychological stress of restraint.

  5. Corticotropin-releasing factor in the basolateral amygdala enhances memory consolidation via an interaction with the beta-adrenoceptor-cAMP pathway: dependence on glucocorticoid receptor activation.

    Roozendaal, Benno; Schelling, Gustav; McGaugh, James L

    2008-06-25

    Extensive evidence indicates that stress hormone effects on the consolidation of emotionally influenced memory involve noradrenergic activation of the basolateral complex of the amygdala (BLA). The present experiments examined whether corticotropin-releasing factor (CRF) modulates memory consolidation via an interaction with the beta-adrenoceptor-cAMP system in the BLA. In a first experiment, male Sprague Dawley rats received bilateral infusions of the CRF-binding protein ligand inhibitor CRF(6-33) into the BLA either alone or together with the CRF receptor antagonist alpha-helical CRF(9-41) immediately after inhibitory avoidance training. CRF(6-33) induced dose-dependent enhancement of 48 h retention latencies, which was blocked by coadministration of alpha-helical CRF(9-41), suggesting that CRF(6-33) enhances memory consolidation by displacing CRF from its binding protein, thereby increasing "free" endogenous CRF concentrations. In a second experiment, intra-BLA infusions of atenolol (beta-adrenoceptor antagonist) and Rp-cAMPS (cAMP inhibitor), but not prazosin (alpha(1)-adrenoceptor antagonist), blocked CRF(6-33)-induced retention enhancement. In a third experiment, the CRF receptor antagonist alpha-helical CRF(9-41) administered into the BLA immediately after training attenuated the dose-response effects of concurrent intra-BLA infusions of clenbuterol (beta-adrenoceptor agonist). In contrast, alpha-helical CRF(9-41) did not alter retention enhancement induced by posttraining intra-BLA infusions of either cirazoline (alpha(1)-adrenoceptor agonist) or 8-br-cAMP (cAMP analog). These findings suggest that CRF facilitates the memory-modulatory effects of noradrenergic stimulation in the BLA via an interaction with the beta-adrenoceptor-cAMP cascade, at a locus between the membrane-bound beta-adrenoceptor and the intracellular cAMP formation site. Moreover, consistent with evidence that glucocorticoids enhance memory consolidation via a similar interaction with the

  6. Neutron-induced alpha radiography

    Pereira, Marco Antonio Stanojev

    2008-01-01

    A new radiography technique to inspect thin samples was developed. Low energy alpha particles, generated by a boron based screen under thermal neutron irradiation, are used as penetrating radiation. The solid state nuclear track detector CR-39 has been used to register the image. The interaction of the α - particles with the CR-39 gives rise to damages which under an adequate chemical etching became tracks the basic units forming the image. A digital system was developed for data acquisition and data analysis as well as for image processing. The irradiation and etching conditions to obtain the best radiography are 1,3 hours and 25 minutes at 70 deg C respectively. For such conditions samples having 10 μm in thickness can be inspected with a spatial resolution of 32 μm. The use of the digital system has reduced the time spent for data acquisition and data analysis and has improved the radiography image visualization. Furthermore, by using the digital system, it was possible to study several new parameters regarding the tracks which are very important to understand and study the image formation theory in solid state nuclear track detectors, the one used in this thesis. Some radiography images are also shown which demonstrate the potential of the proposed radiography technique. When compared with the other radiography techniques already in use to inspect thin samples, the present one developed in the present paper allows a smaller time to obtain the image, it is not necessary to handle liquid radioactive substances, the detector is insensitive to β, γ, X-ray and visible light. (author)

  7. Drug safety is a barrier to the discovery and development of new androgen receptor antagonists.

    Foster, William R; Car, Bruce D; Shi, Hong; Levesque, Paul C; Obermeier, Mary T; Gan, Jinping; Arezzo, Joseph C; Powlin, Stephanie S; Dinchuk, Joseph E; Balog, Aaron; Salvati, Mark E; Attar, Ricardo M; Gottardis, Marco M

    2011-04-01

    Androgen receptor (AR) antagonists are part of the standard of care for prostate cancer. Despite the almost inevitable development of resistance in prostate tumors to AR antagonists, no new AR antagonists have been approved for over a decade. Treatment failure is due in part to mutations that increase activity of AR in response to lower ligand concentrations as well as to mutations that result in AR response to a broader range of ligands. The failure to discover new AR antagonists has occurred in the face of continued research; to enable progress, a clear understanding of the reasons for failure is required. Non-clinical drug safety studies and safety pharmacology assays were performed on previously approved AR antagonists (bicalutamide, flutamide, nilutamide), next generation antagonists in clinical testing (MDV3100, BMS-641988), and a pre-clinical drug candidate (BMS-501949). In addition, non-clinical studies with AR mutant mice, and EEG recordings in rats were performed. Non-clinical findings are compared to disclosures of clinical trial results. As a drug class, AR antagonists cause seizure in animals by an off-target mechanism and are found in vitro to inhibit GABA-A currents. Clinical trials of candidate next generation AR antagonists identify seizure as a clinical safety risk. Non-clinical drug safety profiles of the AR antagonist drug class create a significant barrier to the identification of next generation AR antagonists. GABA-A inhibition is a common off-target activity of approved and next generation AR antagonists potentially explaining some side effects and safety hazards of this class of drugs. Copyright © 2010 Wiley-Liss, Inc.

  8. Determination of alpha radionuclides in fish

    Pernicka, L.; Matel, L.; Rosskopfova, O.

    2002-01-01

    The specific activity of alpha radionuclides was determined in biological samples. The biological samples were chosen in kinds of fish, concretely mackerels, herrings and haddocks. Experimental data were presented on the poster

  9. Alpha decay property of Pb parent

    Bai, G.M. Carmel Vigila; Amala, C.; Santhosh Kumar, S.

    2003-01-01

    In this work, the half-lives of alpha decay have been calculated from 182-210 Pb nuclei, both in two sphere approximation and taking care the deformation effects and compared with the available theoretical and experimental data

  10. Alpha particle radiography of small insects

    Chingshen Su

    1993-01-01

    Radiographies of ants, mosquitoes, cockroaches and small bugs have been done with a radioisotope 244 Cm alpha source. Energy of alpha particles was varied by attenuating the 5.81 MeV alpha particles with adjustable air spacings from the source to the sample. The LR-115 was used to register radiographs. The image of the insect registered on the LR-115 was etched out in a 2.5 N NaOH solution at 52 o C for certain minutes, depending on various irradiation conditions for the insects. For larger insects, a scanning device for the alpha particle irradiation has been fabricated to take the radiograph of whole body of the insect, and the scanning period can be selected to give desired irradiation dosage. A CCDTV camera system connected to a microscope interfaced to an IBM/AT computer is used to register the microscopic image of the radiograph and to print it out with a video copy processor. (Author)

  11. Low Cost silicon photodiodes for alpha spectrometry

    Khoury, H.; Lopes, A.; Hazin, C.; Lira, C.B.; Silva, E. da

    1998-01-01

    This study was carried out to evaluate the suitability of using commercially available photodiodes for alpha spectrometry, since the principle on which both operate are similar. Photodiodes are low priced compared to the commonly used semiconductor detectors making them potentially useful for research and teaching purposes. Very thin calibrated alpha sources of 2 41 A m, 2 44 C m and 2 35 U , produced at the Metrology Laboratory of IRD/CNEN, were used to test the performance of three photodiodes. The results showed that the responses of the photodiodes were linear with the alpha particle energy and that the energy resolution varied between 0,79% and 0,45%, with an efficiency of 8%. The resolution and efficiency presented by the photodiodes tested are similar to those obtained with other semiconductor detectors, evidencing that they can be used successfully as alpha detectors

  12. Genetics Home Reference: alpha-mannosidosis

    ... the lysosomes , which are compartments that digest and recycle materials in the cell. Within lysosomes, the enzyme ... JC, Saftig P, Fogh J, Malm D. Natural history of alpha mannosidosis a longitudinal study. Orphanet J ...

  13. Targeted alpha therapy: Applications and current status

    Bruchertseifer, Frank, E-mail: frank.bruchertseifer@ec.europa.eu [European Commission, Joint Research Centre, Karlsruhe (Germany)

    2017-07-01

    Full text: The field of targeted alpha therapy has been developed rapidly in the last decade. Besides {sup 223}Ra, {sup 211}At and {sup 212}Pb/{sup 212}Bi the alpha emitters {sup 225}Ac and {sup 213}Bi are promising therapeutic radionuclides for application in targeted alpha therapy of cancer and infectious diseases. The presentation will give a short overview about the current clinical treatments with alpha emitting radionuclides and will place an emphasis on the most promising clinical testing of peptides and antibodies labelled with {sup 225}Ac and {sup 213}Bi for treatment of metastatic castration-resistant prostate cancer patients with glioma and glioblastoma multiform, PSMA-positive tumor phenotype and bladder carcinoma in situ. (author)

  14. Liquid scintillation alpha particle spectrometry. Progress report

    Bell, L.L.; Hakooz, S.A.; Johnson, L.O.; Nieschmidt, E.B.; Meikrantz, D.H.

    1979-12-01

    Objective to develop a technique whereby Pu may be put into solution, extracted by solvent extraction into a suitable extractive scintillant and subsequently counted. Presented here are results of attempts to separate beta and alpha activities through pulse shape discrimination. A qualitative discussion is given which yields alpha particle peak widths, resolution and response. The detection efficiency for alpha particles in a liquid scintillant is 100%. Present detection sensitivities of the equipment being used are: 4.5 x 10 -6 μCi (100 s), 1.2 x 10 -6 μCi (1000 s), and 4.0 x 10 -7 μCi (10,000 s) at the 3 sigma level. The detectability of a particular alpha-emitting species is strongly dependent upon the population of other species. The ability to discriminate depends upon the system resolution. 14 figures, 2 tables

  15. Solar Imagery - Chromosphere - H-Alpha

    National Oceanic and Atmospheric Administration, Department of Commerce — Collection includes a variety of H-alpha photographic datasets contributed by a number of national and private solar observatories located worldwide. Solar...

  16. Strichartz estimates on $alpha$-modulation spaces

    Weichao Guo

    2013-05-01

    Full Text Available In this article, we consider some dispersive equations, including Schrodinger equations, nonelliptic Schrodinger equations, and wave equations. We develop some Strichartz estimates in the frame of alpha-modulation spaces.

  17. NEW APPROACHES TO CONFINED ALPHA DIAGNOSTICS

    FISHER,R.K

    2004-04-01

    Three new approaches to obtain information on the confined fast alphas in International Thermonuclear Experimental Reactor (ITER) are proposed. The first technique measures the energetic charge exchange (CX) neutrals that result from the alpha collision-induced knock-on fuel ion tails undergoing electron capture on the MeV D neutral beams planned for heating and current drive. The second technique measures the energetic knock-on neutron tail due to alphas using the lengths of the proton recoil tracks produced by neutron collisions in nuclear emulsions. The range of the 14 to 20 MeV recoil protons increases by {approx}140 microns per MeV. The third approach would measure the CX helium neutrals resulting from confined alphas capturing two electrons in the ablation cloud surrounding a dense gas jet that has been proposed for disruption mitigation in ITER.

  18. Alpha particles spectrometer with photodiode PIN

    Chacon R, A.; Hernandez V, R.; Hernandez D, V. M.; Vega C, H. R.; Ramirez G, J.

    2009-10-01

    The radiation propagates in form of electromagnetic waves or corpuscular radiation; if the radiation energy causes ionization in environment that crosses it is considered ionizing radiation. To detect radiation several detectors types are used, if the radiation are alpha particles are used detectors proportional type or trace elements. In this work the design results, construction and tests of an alpha particles spectrometer are presented, which was designed starting from a photodiode PIN type. The system design was simulated with a code for electronic circuits. With results of simulation phase was constructed the electronic phase that is coupled to a multichannel analyzer. The resulting electronic is evaluated analyzing the electronic circuit performance before an alphas triple source and alpha radiation that produce two smoke detectors of domestic use. On the tests phase we find that the system allows obtain, in a multichannel, the pulses height spectrum, with which we calibrate the system. (Author)

  19. NEW APPROACHES TO CONFINED ALPHA DIAGNOSTICS

    FISHER, R.K.

    2004-01-01

    Three new approaches to obtain information on the confined fast alphas in International Thermonuclear Experimental Reactor (ITER) are proposed. The first technique measures the energetic charge exchange (CX) neutrals that result from the alpha collision-induced knock-on fuel ion tails undergoing electron capture on the MeV D neutral beams planned for heating and current drive. The second technique measures the energetic knock-on neutron tail due to alphas using the lengths of the proton recoil tracks produced by neutron collisions in nuclear emulsions. The range of the 14 to 20 MeV recoil protons increases by ∼140 microns per MeV. The third approach would measure the CX helium neutrals resulting from confined alphas capturing two electrons in the ablation cloud surrounding a dense gas jet that has been proposed for disruption mitigation in ITER

  20. Calibration of alpha surface contamination monitor

    Freitas, I.S.M. de; Goncalez, O.L.

    1990-01-01

    In this work, the results, as well as the methodology, of the calibration of an alpha surface contamination monitor are presented. The calibration factors are obtained by least-squares fitting with effective variance. (author)

  1. Cytokine vaccination: neutralising IL-1alpha autoantibodies induced by immunisation with homologous IL-1alpha

    Svenson, M; Hansen, M B; Thomsen, Allan Randrup

    2000-01-01

    with IL-1alpha coupled to purified protein derivative of tuberculin (PPD). Both unprimed and primed animals developed IgG aAb to IL-1alpha. These aAb persisted at high levels more than 100 days after vaccination and did not cross-react with murine IL-1beta. The induced anti-IL-1alpha aAb inhibited binding...... in mice by vaccination with recombinant murine IL-1alpha conjugated to PPD. Studies of the effects of IL-1alpha aAb in such animals may help clarify the importance of naturally occurring IL-1alpha aAb in humans and permit the evaluation of future therapies with cytokine aAb in patients...

  2. Energy dependence of event shapes and of $\\alpha_s$ at LEP 2

    Abreu, P; Adye, T; Adzic, P; Albrecht, Z; Alderweireld, T; Alekseev, G D; Alemany, R; Allmendinger, T; Allport, P P; Almehed, S; Amaldi, Ugo; Amapane, N; Amato, S; Anassontzis, E G; Andersson, P; Andreazza, A; Andringa, S; Antilogus, P; Apel, W D; Arnoud, Y; Åsman, B; Augustin, J E; Augustinus, A; Baillon, Paul; Bambade, P; Barão, F; Barbiellini, Guido; Barbier, R; Bardin, Dimitri Yuri; Barker, G; Baroncelli, A; Battaglia, Marco; Baubillier, M; Becks, K H; Begalli, M; Behrmann, A; Beillière, P; Belokopytov, Yu A; Belous, K S; Benekos, N C; Benvenuti, Alberto C; Bérat, C; Berggren, M; Bertini, D; Bertrand, D; Besançon, M; Bianchi, F; Bigi, M; Bilenky, S M; Bizouard, M A; Bloch, D; Blom, H M; Bonesini, M; Bonivento, W; Boonekamp, M; Booth, P S L; Borgland, A W; Borisov, G; Bosio, C; Botner, O; Boudinov, E; Bouquet, B; Bourdarios, C; Bowcock, T J V; Boyko, I; Bozovic, I; Bozzo, M; Branchini, P; Brenke, T; Brenner, R A; Brückman, P; Brunet, J M; Bugge, L; Buran, T; Burgsmüller, T; Buschbeck, Brigitte; Buschmann, P; Cabrera, S; Caccia, M; Calvi, M; Camporesi, T; Canale, V; Carena, F; Carroll, L; Caso, Carlo; Castillo-Gimenez, M V; Cattai, A; Cavallo, F R; Chabaud, V; Chapkin, M M; Charpentier, P; Chaussard, L; Checchia, P; Chelkov, G A; Chierici, R; Chliapnikov, P V; Chochula, P; Chorowicz, V; Chudoba, J; Cieslik, K; Collins, P; Contri, R; Cortina, E; Cosme, G; Cossutti, F; Cowell, J H; Crawley, H B; Crennell, D J; Crépé, S; Crosetti, G; Cuevas-Maestro, J; Czellar, S; Davenport, Martyn; Da Silva, W; Deghorain, A; Della Ricca, G; Delpierre, P A; Demaria, N; De Angelis, A; de Boer, Wim; De Clercq, C; De Lotto, B; De Min, A; De Paula, L S; Dijkstra, H; Di Ciaccio, Lucia; Dolbeau, J; Doroba, K; Dracos, M; Drees, J; Dris, M; Duperrin, A; Durand, J D; Eigen, G; Ekelöf, T J C; Ekspong, Gösta; Ellert, M; Elsing, M; Engel, J P; Erzen, B; Espirito-Santo, M C; Falk, E; Fanourakis, G K; Fassouliotis, D; Fayot, J; Feindt, Michael; Fenyuk, A; Ferrari, P; Ferrer, A; Ferrer-Ribas, E; Ferro, F; Fichet, S; Firestone, A; Flagmeyer, U; Föth, H; Fokitis, E; Fontanelli, F; Franek, B J; Frodesen, A G; Frühwirth, R; Fulda-Quenzer, F; Fuster, J A; Galloni, A; Gamba, D; Gamblin, S; Gandelman, M; García, C; Gaspar, C; Gaspar, M; Gasparini, U; Gavillet, P; Gazis, E N; Gelé, D; Ghodbane, N; Gil, I; Glege, F; Gokieli, R; Golob, B; Gómez-Ceballos, G; Gonçalves, P; González-Caballero, I; Gopal, Gian P; Gorn, L; Górski, M; Guz, Yu; Gracco, Valerio; Grahl, J; Graziani, E; Green, C; Grimm, H J; Gris, P; Grosdidier, G; Grzelak, K; Günther, M; Guy, J; Hahn, F; Hahn, S; Haider, S; Hallgren, A; Hamacher, K; Hansen, J; Harris, F J; Hedberg, V; Heising, S; Hernández, J J; Herquet, P; Herr, H; Hessing, T L; Heuser, J M; Higón, E; Holmgren, S O; Holt, P J; Hoorelbeke, S; Houlden, M A; Hrubec, Josef; Huet, K; Hughes, G J; Hultqvist, K; Jackson, J N; Jacobsson, R; Jalocha, P; Janik, R; Jarlskog, C; Jarlskog, G; Jarry, P; Jean-Marie, B; Johansson, E K; Jönsson, P E; Joram, C; Juillot, P; Kapusta, F; Karafasoulis, K; Katsanevas, S; Katsoufis, E C; Keränen, R; Kersevan, Borut P; Khomenko, B A; Khovanskii, N N; Kiiskinen, A P; King, B J; Kinvig, A; Kjaer, N J; Klapp, O; Klein, H; Kluit, P M; Kokkinias, P; Koratzinos, M; Kostyukhin, V; Kourkoumelis, C; Kuznetsov, O; Krammer, Manfred; Kriznic, E; Krstic, J; Krumshtein, Z; Kubinec, P; Kurowska, J; Kurvinen, K L; Lamsa, J; Lane, D W; Langefeld, P; Lapin, V; Laugier, J P; Lauhakangas, R; Leder, Gerhard; Ledroit, F; Lefébure, V; Leinonen, L; Leisos, A; Leitner, R; Lemonne, J; Lenzen, Georg; Lepeltier, V; Lesiak, T; Lethuillier, M; Libby, J; Liko, D; Lipniacka, A; Lippi, I; Lörstad, B; Loken, J G; Lopes, J H; López, J M; López-Fernandez, R; Loukas, D; Lutz, P; Lyons, L; MacNaughton, J N; Mahon, J R; Maio, A; Malek, A; Malmgren, T G M; Maltezos, S; Malychev, V; Mandl, F; Marco, J; Marco, R P; Maréchal, B; Margoni, M; Marin, J C; Mariotti, C; Markou, A; Martínez-Rivero, C; Martínez-Vidal, F; Martí i García, S; Mastroyiannopoulos, N; Matorras, F; Matteuzzi, C; Matthiae, Giorgio; Masik, J; Mazzucato, F; Mazzucato, M; McCubbin, M L; McKay, R; McNulty, R; McPherson, G; Meroni, C; Meyer, W T; Migliore, E; Mirabito, L; Mitaroff, Winfried A; Mjörnmark, U; Moa, T; Moch, M; Møller, R; Mönig, K; Monge, M R; Moreau, X; Morettini, P; Morton, G A; Müller, U; Münich, K; Mulders, M; Mulet-Marquis, C; Muresan, R; Murray, W J; Muryn, B; Myatt, Gerald; Myklebust, T; Naraghi, F; Nassiakou, M; Navarria, Francesco Luigi; Navas, S; Nawrocki, K; Negri, P; Némécek, S; Neufeld, N; Neumeister, N; Nicolaidou, R; Nielsen, B S; Nikolenko, M; Nomokonov, V P; Normand, Ainsley; Nygren, A; Obraztsov, V F; Olshevskii, A G; Onofre, A; Orava, Risto; Orazi, G; Österberg, K; Ouraou, A; Paganoni, M; Paiano, S; Pain, R; Paiva, R; Palacios, J; Palka, H; Papadopoulou, T D; Papageorgiou, K; Pape, L; Parkes, C; Parodi, F; Parzefall, U; Passeri, A; Passon, O; Pegoraro, M; Peralta, L; Pernicka, Manfred; Perrotta, A; Petridou, C; Petrolini, A; Phillips, H T; Pierre, F; Pimenta, M; Piotto, E; Podobnik, T; Pol, M E; Polok, G; Poropat, P; Pozdnyakov, V; Privitera, P; Pukhaeva, N; Pullia, Antonio; Radojicic, D; Ragazzi, S; Rahmani, H; Ratoff, P N; Read, A L; Rebecchi, P; Redaelli, N G; Regler, Meinhard; Reid, D; Reinhardt, R; Renton, P B; Resvanis, L K; Richard, F; Rídky, J; Rinaudo, G; Røhne, O M; Romero, A; Ronchese, P; Rosenberg, E I; Rosinsky, P; Roudeau, Patrick; Rovelli, T; Royon, C; Ruhlmann-Kleider, V; Ruiz, A; Saarikko, H; Sacquin, Yu; Sadovskii, A; Sajot, G; Salt, J; Sampsonidis, D; Sannino, M; Schneider, H; Schwemling, P; Schwering, B; Schwickerath, U; Schyns, M A E; Scuri, F; Seager, P; Sedykh, Yu; Segar, A M; Sekulin, R L; Shellard, R C; Sheridan, A; Siebel, M; Simard, L C; Simonetto, F; Sissakian, A N; Smadja, G; Smirnov, N; Smirnova, O G; Smith, G R; Sopczak, André; Sosnowski, R; Spassoff, Tz; Spiriti, E; Sponholz, P; Squarcia, S; Stanescu, C; Stanic, S; Stevenson, K; Stocchi, A; Strub, R; Stugu, B; Szczekowski, M; Szeptycka, M; Tabarelli de Fatis, T; Tegenfeldt, F; Terranova, F; Thomas, J; Timmermans, J; Tinti, N; Tkatchev, L G; Todorova-Nová, S; Tomaradze, A G; Tomé, B; Tonazzo, A; Tortora, L; Tranströmer, G; Treille, D; Tristram, G; Trochimczuk, M; Troncon, C; Tsirou, A L; Turluer, M L; Tyapkin, I A; Tzamarias, S; Ullaland, O; Uvarov, V; Valenti, G; Vallazza, E; Van der Velde, C; van Apeldoorn, G W; van Dam, P; Van Doninck, W K; Van Eldik, J; Van Lysebetten, A; Van Vulpen, I B; Vassilopoulos, N; Vegni, G; Ventura, L; Venus, W A; Verbeure, F; Verlato, M; Vertogradov, L S; Verzi, V; Vilanova, D; Vitale, L; Vlasov, E; Vodopyanov, A S; Vollmer, C F; Voulgaris, G; Vrba, V; Wahlen, H; Walck, C; Weiser, C; Wicke, D; Wickens, J H; Wilkinson, G R; Winter, M; Witek, M; Wolf, G; Yi, J; Yushchenko, O P; Zaitsev, A; Zalewska-Bak, A; Zalewski, Piotr; Zavrtanik, D; Zevgolatakos, E; Zimin, N I; Zucchelli, G C; Zumerle, G

    1999-01-01

    Infrared and collinear safe event shape distributions and their mean values are determined using the data taken at ve di erent centre of mass energies above $M_Z$ with the DELPHI detector at LEP. From the event shapes, the strong coupling $\\alpha_s$ is extracted in $O(\\alpha^2_s)$, NLLA and a combined scheme using hadronisation corrections evaluated with fragmentation model generators as well as using an analytical power ansatz. Comparing these measurements to those obtained at MZ, the energy dependence (running) of $\\alpha_s$ is accessible. The logarithmic energy slope of the inverse strong coupling is measured to be $d\\alpha_{s}^{-1}/d log(E_{cm}) = 1.39 \\pm 0.34(stat) \\pm 0.17(syst)$, in good agreement with the QCD expectation of 1.27.

  3. Immunodetection of Thyroid Hormone Receptor (Alpha1/Alpha2) in the Rat Uterus and Oviduct

    Öner, Jale; Öner, Hakan

    2007-01-01

    The aim of this study was to investigate the immunolocalization and the existence of thyroid hormone receptors (THR) (alpha1/alpha2) in rat uterus and oviduct. For this purpose 6 female Wistar albino rats found in estrous period were used. Tissue samples fixed in 10% neutral formalin were examined immunohistochemically. Sections were incubated with primary mouse-monoclonal THR (alpha1/alpha2) antibody. In uterus, THR (alpha1/alpha2) immunoreacted strongly with uterine luminal epithelium, endometrial gland epithelium and endometrial stromal cells and, moderately with myometrial smooth muscle. In oviduct, they were observed moderately in the epithelium of the tube and the smooth muscle cells of the muscular layer. In conclusion, the presence of THR in uterus and oviduct suggests that these organs are an active site of thyroid hormones

  4. Influence of fast alpha diffusion and thermal alpha buildup on tokamak reactor performance

    Uckan, N.A.; Tolliver, J.S.; Houlberg, W.A.; Attenberger, S.E.

    1988-01-01

    The effect of fast alpha diffusion and thermal alpha accumulation on the confinement capability of a candidate Engineering Test Reactor plasma (Tokamak Ignition/Burn Experimental Reactor) in achieving ignition and steady-state driven operation has been assessed using both global and 1-1/2-dimensional transport models. Estimates are made of the threshold for radial diffusion of fast alphas and thermal alpha buildup. It is shown that a relatively low level of radial transport, when combined with large gradients in the fast alpha density, leads to a significant radial flow with a deleterious effect on plasma performance. Similarly, modest levels of thermal alpha concentration significantly influence the ignition and steady-state burn capability

  5. Research progress of antagonistic interactions among root canal irrigations disease

    Chen QU

    2013-07-01

    Full Text Available Root canal therapy is the most effective way to treat various pulposis and periapical disease. Simple mechanical apparatus can not clean root canal thoroughly, but may affect tight filling instead. It can achieve a satisfactory cleansing effect only when it is combined with a chemical solution. Irrigation fluid for root canal should possess the properties of tissue dissolution, antimicrobial, lubrication, and removal of smear layer. So far, no solution is able to fulfill all these functions. Therefore, a combined use of multiple irrigation solutions is suggested. It can not only achieve good effect in cleaning and disinfection, also it can lower the concentration of different solutions, thus reducing the side effects. Nevertheless, some experiments proved that antagonism existed among the chemicals used for irrigations. The purpose of present article is to review the antagonistic effect among the chemicals used for irrigation when they are used together for root canal treatment.

  6. Effects of TNF antagonists on immune and neuroendocrine system

    M. Cutolo

    2011-09-01

    Full Text Available In the article, the literature on the effects of TNFa-antagonists (etanercept, infliximab and adalimumab on the immune system is reviewed. These biologic agents are employed in chronic inflammatory diseases such as rheumatoid arthritis, seronegative spondyloarthritides, as well as psoriasis and Crohn’s disease. The differences of these drugs, testified by the different effects on the immune response, are discussed. These molecules exert their effect through cytokine inhibition, but they present striking differences since they can modulate macrophage activity, T cells apoptosis, leukocyte migration, and angiogenesis to a different degree. Some studies showed that these agents also affect the hypothalamo- pituitary-adrenal axis. The potential immunogenicity of these biologic agents is also discussed.

  7. Identification of Bexarotene as a PPARγ Antagonist with HDX

    David P. Marciano

    2015-01-01

    Full Text Available The retinoid x receptors (RXRs are the pharmacological target of Bexarotene, an antineoplastic agent indicated for the treatment of cutaneous T cell lymphoma (CTCL. The RXRs form heterodimers with several nuclear receptors (NRs, including peroxisome proliferator-activated receptor gamma (PPARγ, to regulate target gene expression through cooperative recruitment of transcriptional machinery. Here we have applied hydrogen/deuterium exchange (HDX mass spectrometry to characterize the effects of Bexarotene on the conformational plasticity of the intact RXRα:PPARγ heterodimer. Interestingly, addition of Bexarotene to PPARγ in the absence of RXRα induced protection from solvent exchange, suggesting direct receptor binding. This observation was confirmed using a competitive binding assay. Furthermore, Bexarotene functioned as a PPARγ antagonist able to alter rosiglitazone induced transactivation in a cell based promoter:reporter transactivation assay. Together these results highlight the complex polypharmacology of lipophilic NR targeted small molecules and the utility of HDX for identifying and characterizing these interactions.

  8. Rational use of calcium-channel antagonists in Raynaud's phenomenon.

    Sturgill, M G; Seibold, J R

    1998-11-01

    Raynaud's phenomenon (RP) is a peripheral circulatory disorder characterized by sudden episodes of digital artery spasm, often precipitated by cold temperature or emotional stress. Although the cause of RP is not fully known, it appears to involve inappropriate adrenergic response to cold stimuli. Treatment of RP is conservative in most patients, but in patients with severe disease includes the use of agents that promote digital vasodilation. The calcium-channel antagonists, particularly the dihydropyridine derivative nifedipine, are the most thoroughly studied drug class for the treatment of RP. Approximately two thirds of patients respond favorably, with significant reductions in the frequency and severity of vasospastic attacks. Nifedipine use is often limited by the appearance of adverse vasodilatory effects such as headache or peripheral edema. The newer second-generation dihydropyridines such as amlodipine, isradipine, nicardipine, and felodipine also appear to be effective in patients with RP and may be associated with fewer adverse effects.

  9. Antagonistic Bioactivity of Endophytic Actinomycetes Isolated from Medicinal Plants

    M. Gangwar

    2011-10-01

    Full Text Available Endophytic actinomycetes are promising biocontrol agents for use in agriculture and have been isolated from various plant species. In the present study, 40 endophytic actinomycetes were isolated from roots, stems and leaves of three medicinal plants viz. Aloe vera, Mentha arvensis and Ocimum sanctum. The identification revealed that the majority of the isolates were Streptomyces spp. and the rest were identified as Saccharopolyspora spp., Micromonospora spp. and Actinopolyspora spp. The dual tests revealed that nine endophytic actinomycete isolates displayed a wide spectrum activity against nine fungal phytopathogens. Out of 8 isolates, 90% inhibited the growth of at least one or more phytopathogenic fungi and Saccharopolyspora 0-9 (Out of 8 isolates, 90% inhibited the growth of at least one or more phytopathogenic fungi and Saccharopolyspora 0-9 exhibited antagonistic activity against Aspergillus niger, Aspergillus flavus, Alternaria brassicicola, Botrytis cinerea, Penicillium digitatum, Fusarium oxysporum, Penicillium pinophilum, Phytophthora dresclea and Colletotrichum falcatum.

  10. Lectin interactions with alpha-galactosylated xenoantigens

    Kirkeby, Svend; Moe, Dennis

    2002-01-01

    alpha-Galactosylated xenoantigens (Galalpha1-3Galbeta1-4GlcNAcbeta1 and Galalpha1-3Galbeta1-4GlcNAcbeta1-3Galbeta1-4Glc) are often detected with the alpha-Gal specific lectin Griffonia simplicifolia 1 isolectin B4 (GS1 B4). However, this lectin exhibits a broad and variable specificity for carboh...

  11. Considering the determination of an alpha value

    Lorenz, B.

    1987-01-01

    Following an outline of the most important international methods of evaluating an alpha value (the monetary equivalent of one man-sievert) and an approach deemed suitable for use in the GDR, it is recommended that alpha be taken as 30,000 Mark per man-sievert in national cost-benefit analyses. This value should be revisited every five to ten years. (author)

  12. The ALPHA Experiment a Cold Antihydrogen Trap

    Bertsche, W; Bowe, P D; Cesar, C L; Chapman, S; Charlton, M; Chartier, M; Deutsch, A; Fajans, J; Fujiwara, M C; Funakoshi, R; Gill, D; Gomberoff, K; Grote, D P; Hangst, J S; Hayano, R S; Jenkins, M; Jørgensen, L V; Madsen, N; Miranda, D; Nolan, P; Ochanski, K; Olin, A; Page, R D; Posada, L G C; Robicheaux, F; Sarid, E; Telle, H H; Vay, J L; Wurtele, J; van der Werf, D P; Yamazaki, Y

    2005-01-01

    The ALPHA experiment aims to trap antihydrogen as the next crucial step towards a precise CPT test, by a spectroscopic comparison of antihydrogen with hydrogen. The experiment will retain the salient techniques developed by the ATHENA collaboration during the previous phase of antihydrogen experiments at the antiproton decelerator (AD) at CERN. The collaboration has identified the key problems in adding a neutral antiatom trap to the previously developed experimental configuration. The solutions identified by ALPHA are described in this paper.

  13. Self-assembling, dynamic alphaPNAs

    Nielsen, Peter E

    2009-01-01

    In the recent report published in Science, Ghadiri and coworkers describe dynamic tPNAs, alphaPNA derivatives with a nucleobase attached via a thioester bond that are a step forward toward self-repairing and replicating molecules.......In the recent report published in Science, Ghadiri and coworkers describe dynamic tPNAs, alphaPNA derivatives with a nucleobase attached via a thioester bond that are a step forward toward self-repairing and replicating molecules....

  14. Conceptual design report for alpha waste incinerator

    1979-04-01

    The Alpha Waste Incinerator, a new facility in the SRP H-Area, will process transuranic or alpha-contaminated combustible solid wastes. It will seal the radioactive ash and scrubbing salt residues in cans for interim storage in drums on site burial ground pads. This report includes objectives, project estimate, schedule, standards and criteria, excluded costs, safety evaluation, energy consumption, environmental assessment, and key drawings

  15. Alpha-root Processes for Derivatives pricing

    Balakrishna, BS

    2010-01-01

    A class of mean reverting positive stochastic processes driven by alpha-stable distributions, referred to here as alpha-root processes in analogy to the square root process (Cox-Ingersoll-Ross process), is a subclass of affine processes, in particular continuous state branching processes with immigration (CBI processes). Being affine, they provide semi-analytical results for the implied term structures as well as for the characteristic exponents for their associated distributions. Their use h...

  16. Alpha-emitters for medical therapy workshop

    Feinendegen, L.E.; McClure, J.J.

    1996-01-01

    A workshop on ''Alpha-Emitters for Medical Therapy'' was held May 30-31, 1996 in Denver Colorado to identify research goals and potential clinical needs for applying alpha-particle emitters and to provide DOE with sufficient information for future planning. The workshop was attended by 36 participants representing radiooncology, nuclear medicine, immunotherapy, radiobiology, molecular biology, biochemistry, radiopharmaceutical chemistry, dosimetry, and physics. This report provides a summary of the key points and recommendations arrived at during the conference

  17. Production of alpha emitters for therapy

    Vucina, J.; Orlic, M.; Lukic, D.

    2006-01-01

    The basis for the introduction of alpha emitters into nuclear medical practice are their radiobiological properties. High LET values and short ranges in biological tissues are advantageous in comparison with nowadays most often used beta emitters, primarily 90 Y and 131 I. Given are the most important criteria for the introduction of a given radionuclide in the routine use. Shown are the procedures for the production of the most important alpha emitters 211 At, 212 Bi and 213 Bi. (author)

  18. Alpha-emitters for medical therapy workshop

    Feinendegen, L.E.; McClure, J.J.

    1996-12-31

    A workshop on ``Alpha-Emitters for Medical Therapy`` was held May 30-31, 1996 in Denver Colorado to identify research goals and potential clinical needs for applying alpha-particle emitters and to provide DOE with sufficient information for future planning. The workshop was attended by 36 participants representing radiooncology, nuclear medicine, immunotherapy, radiobiology, molecular biology, biochemistry, radiopharmaceutical chemistry, dosimetry, and physics. This report provides a summary of the key points and recommendations arrived at during the conference.

  19. High-Throughput Screening of Small Molecules Identifies Hepcidin Antagonists

    Fung, Eileen; Sugianto, Priscilla; Hsu, Jason; Damoiseaux, Robert; Ganz, Tomas

    2013-01-01

    Anemia of inflammation (AI) is common in patients with infection, autoimmune diseases, cancer, and chronic kidney disease. Unless the underlying condition can be reversed, treatment options are limited to erythropoiesis-stimulating agents with or without intravenous iron therapy, modalities that are not always effective and can cause serious adverse effects. Hepcidin, the iron regulatory hormone, has been identified as a pathogenic factor in the development of AI. To explore new therapeutic options for AI and other iron-related disorders caused by hepcidin excess, we developed a cell-based screen to identify hepcidin antagonists. Of the 70,000 small molecules in the library, we identified 14 compounds that antagonized the hepcidin effect on ferroportin. One of these was fursultiamine, a Food and Drug Administration (FDA)–approved thiamine derivative. Fursultiamine directly interfered with hepcidin binding to its receptor, ferroportin, by blocking ferroportin C326 thiol residue essential for hepcidin binding. Consequently, fursultiamine prevented hepcidin-induced ferroportin ubiquitination, endocytosis, and degradation in vitro and allowed continuous cellular iron export despite the presence of hepcidin, with IC50 in the submicromolar range. Thiamine, the fursultiamine metabolite, and benfotiamine, another thiamine derivative, did not interfere with the effect of hepcidin on ferroportin. Other FDA-approved thiol-reactive compounds were at least 1000-fold less potent than fursultiamine in antagonizing hepcidin. In vivo, fursultiamine did not reproducibly antagonize the effect of hepcidin on serum iron, likely because of its rapid conversion to inactive metabolites. Fursultiamine is a unique antagonist of hepcidin in vitro that could serve as a template for the development of drug candidates that inhibit the hepcidin-ferroportin interaction. PMID:23292796

  20. Alpha particle analysis using PEARLS spectrometry

    McKlveen, J.W.; Klingler, G.W.; McDowell, W.J.; Case, G.N.

    1984-01-01

    Alpha particle assay by conventional plate-counting methods is difficult because chemical separation, tracer techniques, and/or self-absorption losses in the final sample may cause either non-reproducible results or create unacceptable errors. PEARLS (Photon-Electron Rejecting Alpha Liquid Scintillation) Spectrometry is an attractive alternative since radionuclides may be extracted into a scintillator in which there would be no self-absorption or geometry problems and in which up to 100% chemical recovery and counting efficiency is possible. Sample preparation may include extraction of the alpha emitter of interest by a specific organic-phase-soluble compound directly into the liquid scintillator. Detection electronics use energy and pulse-shape discrimination to provide discrete alpha spectra and virtual absence of beta and gamma backgrounds. Backgrounds on the order of 0.01 cpm are readily achievable. Accuracy and reproducibility are typically in the 100 +-1% range. Specific procedures have been developed for gross alpha, uranium, plutonium, thorium, and polonium assay. This paper will review liquid scintillation alpha counting methods and reference some of the specific applications. 8 refs., 1 fig

  1. Synthesis of tritiated 1-alpha-methadol and 1-alpha-acetylmethadol

    Thang, D.C.; Nam, N.H.; Pontikis, R. (Institut National de la Sante et de la Recherche Medicale (INSERM), Hopital Fernand Widal, 75 - Paris (France)); Pichat, L. (CEA Centre d' Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette (France). Service des Molecules Marquees)

    1982-04-01

    dl-Methadone was resolved by crystallization of its ammonium d- ..cap alpha.. -bromocamphor-..pi..-sulfonate salt to give d-methadone. The latter in ethyl acetate solution was reduced with tritium gas to 1-..cap alpha..-methadol /sup 3/H in presence of Adams platinum oxide at normal temperature and pressure. Acetylation of 1-..cap alpha..-carbinol hydrochloride by means of acetyl chloride afforded 1-..cap alpha..-acetylmethadol /sup 3/H, specific activity: 20 Ci/mMole. The positions and extent of tritium labelling were determined by /sup 3/H NMR spectroscopy.

  2. Synthesis and antimicrobial evaluation of new 3-alkyl/aryl-2-[((alpha,alpha-diphenyl-alpha-hydroxy)acetyl)hydrazono]-5-methyl-4-thiazolidinones.

    Güzeldemirci, Nuray Ulusoy; Ilhan, Eser; Küçükbasmaci, Omer; Satana, Dilek

    2010-01-01

    New 4-thiazolidinone derivatives of benzilic acid (alpha,alpha-diphenyl-alpha-hydroxyacetic acid) have been synthesized and evaluated for antibacterial and antifungal activities. The reaction of 1- (alpha,alpha-diphenyl-alpha-hydroxy)acetyl-4-alkyl/arylthiosemicarbazides with ethyl 2-bromopropionate gave 3-alkyl/aryl-2-[((alpha,alpha-diphenyl-alpha-hydroxy)acetyl)hydrazono]-5-methyl-4-thiazolidinone derivatives. Their antibacterial and antifungal activities were evaluated against S. aureus ATCC 29213, P. aeruginosa ATCC 27853, E. coli ATCC 25922, C. albicans ATCC 10231, C. parapsilosis ATCC 22019, C. krusei ATCC 6258, T. mentagrophytes var. erinacei NCPF 375, M. gypseum NCPF 580 and T. tonsurans NCPF 245. 3e, 3f, 3g and 3h showed the highest antibacterial activity. Particularly 3a and 3e showed the highest antifungal activities against C. parapsilosis ATCC 22019, T. tonsurans NCPF 245 and M. gypseum NCPF 580.

  3. The adrenergic alpha2 receptor and sexual incentive motivation in male rats.

    Viitamaa, Timo; Haapalinna, Antti; Agmo, Anders

    2006-03-01

    The purpose of the present series of experiments was to determine whether drugs acting at the alpha2-adrenoceptor modify unconditioned sexual incentive motivation in the male rat. To that end a highly specific agonist, dexmedetomidine, a corresponding antagonist, atipamezole, and a less specific antagonist, yohimbine, were administered to groups of sexually inexperienced male rats. The subjects were tested in a large rectangular arena, where a sexually receptive female and an intact male were employed as incentives. The incentive animals were confined behind a wire mesh in opposite corners of the arena. The animals could see, hear and smell each other, but no sexual interaction was possible. Approach to the incentives constituted the measure of incentive motivation. In addition, the test provided data on ambulatory activity and general arousal. Dexmedetomidine, at a dose of 8 microg/kg, produced a slight reduction of sexual incentive motivation. Ambulatory activity and general arousal were also inhibited. Atipamezole, in doses of 0.1 and 0.3mg/kg enhanced the positive incentive properties of the receptive female. A high dose of 1mg/kg did not have any significant effect. Ambulatory activity was slightly reduced by the two larger doses of atipamezole. Yohimbine had a slight stimulatory effect on sexual incentive motivation at a dose (4 mg/kg) that also reduced ambulatory activity and general arousal. It is concluded that blockade of the adrenergic alpha2 receptor stimulates sexual incentive motivation in the male rat whereas stimulation of it has the opposite effect. At present it is not clear if these drug effects are caused by pre- or postsynaptic actions of the drugs, and the importance of secondary changes in other neurotransmitter systems remains unknown.

  4. Development of an image analysis screen for estrogen receptor alpha (ERα) ligands through measurement of nuclear translocation dynamics.

    Dull, Angie; Goncharova, Ekaterina; Hager, Gordon; McMahon, James B

    2010-11-01

    We have developed a robust high-content assay to screen for novel estrogen receptor alpha (ERα) agonists and antagonists by quantitation of cytoplasmic to nuclear translocation of an estrogen receptor chimera in 384-well plates. The screen utilizes a green fluorescent protein tagged-glucocorticoid/estrogen receptor (GFP-GRER) chimera which consisted of the N-terminus of the glucocorticoid receptor fused to the human ER ligand binding domain. The GFP-GRER exhibited cytoplasmic localization in the absence of ERα ligands, and translocated to the nucleus in response to stimulation with ERα agonists or antagonists. The BD Pathway 435 imaging system was used for image acquisition, analysis of translocation dynamics, and cytotoxicity measurements. The assay was validated with known ERα agonists and antagonists, and the Library of Pharmacologically Active Compounds (LOPAC 1280). Additionally, screening of crude natural product extracts demonstrated the robustness of the assay, and the ability to quantitate the effects of toxicity on nuclear translocation dynamics. The GFP-GRER nuclear translocation assay was very robust, with z' values >0.7, CVs screening of natural product extracts. This assay has been developed for future primary screening of synthetic, pure natural products, and natural product extracts libraries available at the National Cancer Institute at Frederick. Copyright © 2010 Elsevier Ltd. All rights reserved.

  5. Antidepressant-like effect of the extract from leaves of Schinus molle L. in mice: evidence for the involvement of the monoaminergic system.

    Machado, Daniele G; Kaster, Manuella P; Binfaré, Ricardo W; Dias, Munique; Santos, Adair R S; Pizzolatti, Moacir G; Brighente, Inês M C; Rodrigues, Ana Lúcia S

    2007-03-30

    Schinus molle L. (Anacardiaceae), among other uses, is popularly employed for the treatment of depression. In this study, the antidepressant-like effect of the hexanic extract from leaves of S. molle was investigated in the mouse tail suspension test (TST), a predictive model of depression. The immobility time in the TST was significantly reduced by the extract (dose range 30-600 mg/kg, p.o.), without accompanying changes in ambulation when assessed in an open-field test. The efficacy of extract was found to be comparable to that of fluoxetine (10 mg/kg, p.o.). The anti-immobility effect of the extract (100 mg/kg, p.o.) was prevented by pretreatment of mice with p-chlorophenylalanine methyl ester (PCPA, 100 mg/kg, i.p., an inhibitor of serotonin synthesis, for four consecutive days), NAN-190 (0.5 mg/kg, i.p., a 5-HT(1A) receptor antagonist), WAY100635 (0.1 mg/kg, s.c., a selective 5-HT(1A) receptor antagonist), ketanserin (5 mg/kg, i.p., a 5-HT(2A/2C) receptor antagonist), MDL72222 (0.1 mg/kg, i.p., a 5-HT(3) receptor antagonist), prazosin (1 mg/kg, i.p., an alpha(1)-adrenoceptor antagonist), yohimbine (1 mg/kg, i.p., an alpha(2)-adrenoceptor antagonist), SCH23390 (0.05 mg/kg, s.c., a D(1) receptor antagonist) or sulpiride (50 mg/kg, i.p., a D(2) receptor antagonist). It may be concluded that the hexanic extract of S. molle produces an antidepressant-like effect that seems to be dependent on its interaction with the serotonergic, noradrenergic and dopaminergic systems. These results provide evidence that the extract from S. molle shares with established antidepressants some pharmacological effects, at least at a preclinical level.

  6. Purification and reconstitution of the calcium antagonist receptor of the voltage-sensitive calcium channel

    Curtis, B.M.

    1986-01-01

    Treatment with digitonin solubilized the calcium antagonist receptor as a stable complex with [ 3 H]nitrendipine from rat brain membranes. The solubilized complex retains allosteric coupling to binding sites for diltiazem, verapamil, and inorganic calcium antagonist sites. The calcium antagonist receptor from cardiac sarcolemma and the transverse-tubule membrane of skeletal muscle is also efficiently solubilized with digitonin and the receptor in all three tissues is a large glycoprotein with a sedimentation coefficient of 20 S. The T-tubule calcium antagonist receptor complex was extensively purified by a combination of chromatography on WGA-Sepharose, ion exchange chromatography, and sedimentation on sucrose gradients to yield preparations estimated to be 41% homogeneous by specific activity and 63% homogeneous by SDS gel electrophoresis. Analysis of SDS gels detect three polypeptides termed α(Mr 135,000), β(Mr 50,000), and γ(Mr 32,000) as noncovalently associated subunits of the calcium antagonist receptor. The α and γ subunits are glycosylated polypeptides, and the molecular weight of the core polypeptides are 108,000 and 24,000 respectively. The calcium antagonist receptor was reconstituted into a phospholipid bilayer by adding CHAPS and exogeneous lipid to the purified receptor followed by rapid detergent removal. This procedure resulted in the incorporation of 45% of the calcium antagonist receptor into closed phospholipid vesicles. Data suggests that the α, β, and γ subunits of the T-tubule calcium antagonist receptor are sufficient to form a functional calcium channel

  7. Survivin mRNA antagonists using locked nucleic acid, potential for molecular cancer therapy

    Fisker, Niels; Westergaard, Majken; Hansen, Henrik Frydenlund

    2007-01-01

    We have investigated the effects of different locked nucleic acid modified antisense mRNA antagonists against Survivin in a prostate cancer model. These mRNA antagonists were found to be potent inhibitors of Survivin expression at low nanomolar concentrations. Additionally there was a pronounced ...

  8. Agar composition affects in vitro screening of biocontrol activity of antagonistic microorganisms

    Bosmans, Lien; De Bruijn, I.; de Mot, Rene; Readers, Hans; Lievens, Bart

    2016-01-01

    Agar-based screening assays are the method of choice when evaluating antagonistic potential of bacterial biocontrol-candidates against pathogens.Weshowed thatwhen using the samemedium, but different agar compositions, the activity of a bacterial antagonist against Agrobacteriumwas strongly affected.

  9. Benzimidazoles as benzamide replacements within cyclohexane-based CC chemokine receptor 2 (CCR2) antagonists.

    Cherney, Robert J; Mo, Ruowei; Meyer, Dayton T; Pechulis, Anthony D; Guaciaro, Michael A; Lo, Yvonne C; Yang, Gengjie; Miller, Persymphonie B; Scherle, Peggy A; Zhao, Qihong; Cvijic, Mary Ellen; Barrish, Joel C; Decicco, Carl P; Carter, Percy H

    2012-10-01

    We describe the design, synthesis, and evaluation of benzimidazoles as benzamide replacements within a series of trisubstituted cyclohexane CCR2 antagonists. 7-Trifluoromethylbenzimidazoles displayed potent binding and functional antagonism of CCR2 while being selective over CCR3. These benzimidazoles were also incorporated into lactam-containing antagonists, thus completely eliminating the customary bis-amide. Copyright © 2012 Elsevier Ltd. All rights reserved.

  10. Examining the Conservation of Kinks in Alpha Helices.

    Eleanor C Law

    Full Text Available Kinks are a structural feature of alpha-helices and many are known to have functional roles. Kinks have previously tended to be defined in a binary fashion. In this paper we have deliberately moved towards defining them on a continuum, which given the unimodal distribution of kink angles is a better description. From this perspective, we examine the conservation of kinks in proteins. We find that kink angles are not generally a conserved property of homologs, pointing either to their not being functionally critical or to their function being related to conformational flexibility. In the latter case, the different structures of homologs are providing snapshots of different conformations. Sequence identity between homologous helices is informative in terms of kink conservation, but almost equally so is the sequence identity of residues in spatial proximity to the kink. In the specific case of proline, which is known to be prevalent in kinked helices, loss of a proline from a kinked helix often also results in the loss of a kink or reduction in its kink angle. We carried out a study of the seven transmembrane helices in the GPCR family and found that changes in kinks could be related both to subfamilies of GPCRs and also, in a particular subfamily, to the binding of agonists or antagonists. These results suggest conformational change upon receptor activation within the GPCR family. We also found correlation between kink angles in different helices, and the possibility of concerted motion could be investigated further by applying our method to molecular dynamics simulations. These observations reinforce the belief that helix kinks are key, functional, flexible points in structures.

  11. /sup 58,60,62/Ni (. cap alpha. ,p) three--nucleon transfer reactions and. cap alpha. optical potential ambiguities

    Yuanda, Wang; Xiuming, Bao; Zhiqiang, Mao; Rongfang, Yuan; Keling, Wen; Binyin, Huang; Zhifu, Wang; Shuming, Li; Jianan, Wang; Zuxun, Sun; others, and

    1985-11-01

    The differential cross sections are measured using 26.0 MeV ..cap alpha.. particle for /sup 58,62/Ni(..cap alpha.., ..cap alpha..) /sup 58,62/Ni and /sup 58,62/Ni(..cap alpha..,p) /sup 61,65/Cu reactions as well as 25.4 MeV ..cap alpha.. particle for /sup 60/Ni(..cap alpha.., ..cap alpha..)/sup 69/Ni and /sup 60/Ni(..cap alpha.., p)/sup 63/Cu reactions. Consistent calculations with optical model and ZR DWBA are made for (..cap alpha.., ..cap alpha..) and (..cap alpha.., p) reactions by using of single, two, three and four nucleon optical potential parameters. For elastic scattering due to the ..cap alpha.. optical potential ambiguities, all the above optical potential can reproduce the experimental angular distributions. However, the single, two and three nucleon potential, including the Baird's mass systematics and the Chang's energy systematics of ..cap alpha.. potentials, obviously can not provide a reasonable fitting with the (..cap alpha..,p) reaction experimental data. Only the results from the four nucleon potential is in good agreement with the (..cap alpha..,p) reaction experimental data. This reveals that in the ..cap alpha..-particle induced transfer reactions, the real depth of the ..cap alpha..-nucleus optical potential should be rather deep.

  12. Anti-IL-1alpha autoantibodies in early rheumatoid arthritis

    Forslind, K; Svensson, Birte; Svenson, M

    2001-01-01

    To investigate the potential predictive value of autoantibodies against IL1-alpha (anti-IL-1alpha) in patients with early rheumatoid arthritis (RA).......To investigate the potential predictive value of autoantibodies against IL1-alpha (anti-IL-1alpha) in patients with early rheumatoid arthritis (RA)....

  13. Testing hypotheses involving Cronbach's alpha using marginal models

    Kuijpers, R.E.; van der Ark, L.A.; Croon, M.A.

    2013-01-01

    We discuss the statistical testing of three relevant hypotheses involving Cronbach's alpha: one where alpha equals a particular criterion; a second testing the equality of two alpha coefficients for independent samples; and a third testing the equality of two alpha coefficients for dependent

  14. Anti-pp,. cap alpha cap alpha. and p. cap alpha. elastic scattering at high energies and Chou-Yang conjecture

    Saleem, M.; Fazal-e-Aleem; Rifique, M.

    1987-03-01

    The recent experimental measurements for anti-pp and ..cap alpha cap alpha.. elastic scattering at high energies have shown that the Chou-Yang conjecture regarding the relationship between the electromagnetic and the hadronic form factor of a particle is only an approximation. A new ansatz has been proposed to obtain hadronic form factors of proton and the ..cap alpha..-particle. These form factors have been used to explain the various characteristics of anti-pp, ..cap alpha cap alpha.. and p..cap alpha.. elastic scattering at high energies.

  15. Infusion of adrenergic receptor agonists and antagonists into the locus coeruleus and ventricular system of the brain. Effects on swim-motivated and spontaneous motor activity.

    Weiss, J M; Simson, P G; Hoffman, L J; Ambrose, M J; Cooper, S; Webster, A

    1986-04-01

    These studies examined how pharmacological stimulation and blockade of alpha receptors would affect active motor behavior in rats. In experiment I, alpha-2 receptor antagonists (piperoxane, yohimbine) and agonists [clonidine, norepinephrine (NE)] were infused into various locations in the ventricular system of the brain, including the locus coeruleus region, and motor activity was measured. Activity was measured principally in a swim test but spontaneous (ambulatory) activity was also recorded while drugs were being infused. When infused into the locus coeruleus region, small doses of the antagonists piperoxane and yohimbine depressed activity in the swim test while infusion of the agonists clonidine and NE had the opposite effect of stimulating activity. These effects were highly specific to the region of the locus coeruleus, since infusions of these drugs into other nearby locations in the ventricular system or use of larger doses had different, often opposite effects. This was especially true of clonidine and NE which profoundly depressed activity when infused posterior to the locus coeruleus, particularly over the dorsal vagal complex. Infusion of small doses of these drugs into the lateral ventricle had effects similar to infusion into the locus coeruleus region, though less pronounced. Changes in spontaneous motor activity were also observed, but this measure differentiated the groups less well than did the swim test. In experiment II, the predominantly postsynaptic receptor agonists isoproterenol (beta agonist) and phenylephrine (alpha-1 agonist) were infused into the ventricular system. Since infusions of piperoxane and yohimbine into the locus coeruleus that decreased activity in experiment I increase the release of NE by blocking alpha-2 inhibitory receptors on cell bodies and dendrites of the locus coeruleus, experiment II tested whether ventricular infusion of predominantly postsynaptic receptor agonists would also decrease activity in the swim test

  16. ALPHA-SYNUCLEIN STRUCTURE, AGGREGATION AND MODULATORS

    Pinakin K. Makwana

    2016-06-01

    Full Text Available Alpha-synuclein is an intrinsically unstructured protein, involved in various neurodegenerative disorders. In vitro/in vivo experiments, as well as genetic mutation studies establish a direct link between alphasynuclein and synucleinopathies. Due to its natively unfolded state, alpha synuclein can adopt numerous conformations upon interaction with its partners and cellular factors, offering explanation for its diverse interactions. Aggregated form of alpha-synuclein has been observed in the brain of patients with synucleinopathies, a hallmark of neurodegeneration, and cell death has been attributed to aggregation induced toxicity. The process of aggregation involves nucleation, followed by intermediate oligomeric states, and finally the fibrillar amyloids. Of the various conformations/species that alpha-synuclein assumes before it transforms into mature amyloid fibrils, the oligomeric species is the most toxic. Thus, an effective way to limit disease progression is by modifying/slowing down protein aggregation/deposition in the brain. Various small natural products, synthetic chemicals, peptides and antibodies specific to alpha-synuclein have been designed/identified to reduce its rate of aggregation. Unfortunately, not even a handful of the molecules have cleared the clinical trials. Even today, medications available for Parkinson’s patients are mostly the drugs that adjust for loss of dopamine in the brain, and hence do not stop the progression of the disease or cure the symptoms. Thus, more molecular level studies are warranted to fully elucidate the process of alpha-synuclein aggregation, which in turn could help in identifying novel therapeutics and preventives. The present review summarizes the insights gained into the structure, in vitro aggregation and inhibitors/modulators of alpha-synuclein aggregation, that can be used to design better and effective inhibitors against the diseases.

  17. Ultrastructural studies of human and rabbit alpha-M-globulins.

    Bloth, B; Chesebro, B; Svehag, S E

    1968-04-01

    Electron micrographs of isolated human alpha(2)M-molecules, obtained by the negative contrast technique, revealed morphologically homogenous structures resembling a graceful monogram of the two letters H and I. The modal values for the length and width of the alpha(2)M particles were 170 A and 100 A, respectively. Purified rabbit alphamacroglobulins contained about 80% alpha(1)M- and 20% alpha(2)M-globulins. The isolated rabbit alpha(1)M- and alpha(2)M-molecules were morphologically indistinguishable from one another and from human alpha(2)M-molecules. Preliminary immunoprecipitation studies demonstrated that the two rabbit alphaM-globulins were antigenically different. Sedimentation constant determinations gave s(20, w) values of 18.8 and 18.2 for rabbit alpha(1)M and alpha(2)M, respectively.

  18. [11C]CHIBA-1001 as a novel PET ligand for alpha7 nicotinic receptors in the brain: a PET study in conscious monkeys.

    Kenji Hashimoto

    Full Text Available BACKGROUND: The alpha7 nicotinic acetylcholine receptors (nAChRs play an important role in the pathophysiology of neuropsychiatric diseases such as schizophrenia and Alzheimer's disease. However, there are currently no suitable positron emission tomography (PET radioligands for imaging alpha7 nAChRs in the intact human brain. Here we report the novel PET radioligand [11C]CHIBA-1001 for in vivo imaging of alpha7 nAChRs in the non-human primate brain. METHODOLOGY/PRINCIPAL FINDINGS: A receptor binding assay showed that CHIBA-1001 was a highly selective ligand at alpha7 nAChRs. Using conscious monkeys, we found that the distribution of radioactivity in the monkey brain after intravenous administration of [11C]CHIBA-1001 was consistent with the regional distribution of alpha7 nAChRs in the monkey brain. The distribution of radioactivity in the brain regions after intravenous administration of [11C]CHIBA-1001 was blocked by pretreatment with the selective alpha7 nAChR agonist SSR180711 (5.0 mg/kg. However, the distribution of [11C]CHIBA-1001 was not altered by pretreatment with the selective alpha4beta2 nAChR agonist A85380 (1.0 mg/kg. Interestingly, the binding of [11C]CHIBA-1001 in the frontal cortex of the monkey brain was significantly decreased by subchronic administration of the N-methyl-D-aspartate (NMDA receptor antagonist phencyclidine (0.3 mg/kg, twice a day for 13 days; which is a non-human primate model of schizophrenia. CONCLUSIONS/SIGNIFICANCE: The present findings suggest that [11C]CHIBA-1001 could be a novel useful PET ligand for in vivo study of the receptor occupancy and pathophysiology of alpha7 nAChRs in the intact brain of patients with neuropsychiatric diseases such as schizophrenia and Alzheimer's disease.

  19. Identification of a novel bile acid in swans, tree ducks, and geese: 3alpha,7alpha,15alpha-trihydroxy-5beta-cholan-24-oic acid.

    Kakiyama, Genta; Iida, Takashi; Goto, Takaaki; Mano, Nariyasu; Goto, Junichi; Nambara, Toshio; Hagey, Lee R; Schteingart, Claudio D; Hofmann, Alan F

    2006-07-01

    By HPLC, a taurine-conjugated bile acid with a retention time different from that of taurocholate was found to be present in the bile of the black-necked swan, Cygnus melanocoryphus. The bile acid was isolated and its structure, established by (1)H and (13)C NMR and mass spectrometry, was that of the taurine N-acyl amidate of 3alpha,7alpha,15alpha-trihydroxy-5beta-cholan-24-oic acid. The compound was shown to have chromatographic and spectroscopic properties that were identical to those of the taurine conjugate of authentic 3alpha,7alpha,15alpha-trihydroxy-5beta-cholan-24-oic acid, previously synthesized by us from ursodeoxycholic acid. By HPLC, the taurine conjugate of 3alpha,7alpha,15alpha-trihydroxy-5beta-cholan-24-oic acid was found to be present in 6 of 6 species in the subfamily Dendrocygninae (tree ducks) and in 10 of 13 species in the subfamily Anserinae (swans and geese) but not in other subfamilies in the Anatidae family. It was also not present in species from the other two families of the order Anseriformes. 3alpha,7alpha,15alpha-Trihydroxy-5beta-cholan-24-oic acid is a new primary bile acid that is present in the biliary bile acids of swans, tree ducks, and geese and may be termed 15alpha-hydroxy-chenodeoxycholic acid.

  20. Caffeine and an adenosine A(2A) receptor antagonist prevent memory impairment and synaptotoxicity in adult rats triggered by a convulsive episode in early life.

    Cognato, Giana P; Agostinho, Paula M; Hockemeyer, Jörg; Müller, Christa E; Souza, Diogo O; Cunha, Rodrigo A

    2010-01-01

    Seizures early in life cause long-term behavioral modifications, namely long-term memory deficits in experimental animals. Since caffeine and adenosine A(2A) receptor (A(2A)R) antagonists prevent memory deficits in adult animals, we now investigated if they also prevented the long-term memory deficits caused by a convulsive period early in life. Administration of kainate (KA, 2 mg/kg) to 7-days-old (P7) rats caused a single period of self-extinguishable convulsions which lead to a poorer memory performance in the Y-maze only when rats were older than 90 days, without modification of locomotion or anxiety-like behavior in the elevated-plus maze. In accordance with the relationship between synaptotoxicity and memory dysfunction, the hippocampus of these adult rats treated with kainate at P7 displayed a lower density of synaptic proteins such as SNAP-25 and syntaxin (but not synaptophysin), as well as vesicular glutamate transporters type 1 (but not vesicular GABA transporters), with no changes in PSD-95, NMDA receptor subunits (NR1, NR2A, NR2B) or alpha-amino-3-hydroxy-5-methylisoxazole-4-propionate receptor subunits (GluR1, GluR2) compared with controls. Caffeine (1 g/L) or the A(2A)R antagonist, KW6002 (3 mg/kg) applied in the drinking water from P21 onwards, prevented these memory deficits in P90 rats treated with KA at P7, as well as the accompanying synaptotoxicity. These results show that a single convulsive episode in early life causes a delayed memory deficit in adulthood accompanied by a glutamatergic synaptotoxicity that was prevented by caffeine or adenosine A(2A)R antagonists.