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Sample records for acetylcholine transporter detected

  1. Spiroindolines identify the vesicular acetylcholine transporter as a novel target for insecticide action.

    Ann Sluder

    Full Text Available The efficacy of all major insecticide classes continues to be eroded by the development of resistance mediated, in part, by selection of alleles encoding insecticide insensitive target proteins. The discovery of new insecticide classes acting at novel protein binding sites is therefore important for the continued protection of the food supply from insect predators, and of human and animal health from insect borne disease. Here we describe a novel class of insecticides (Spiroindolines encompassing molecules that combine excellent activity against major agricultural pest species with low mammalian toxicity. We confidently assign the vesicular acetylcholine transporter as the molecular target of Spiroindolines through the combination of molecular genetics in model organisms with a pharmacological approach in insect tissues. The vesicular acetylcholine transporter can now be added to the list of validated insecticide targets in the acetylcholine signalling pathway and we anticipate that this will lead to the discovery of novel molecules useful in sustaining agriculture. In addition to their potential as insecticides and nematocides, Spiroindolines represent the only other class of chemical ligands for the vesicular acetylcholine transporter since those based on the discovery of vesamicol over 40 years ago, and as such, have potential to provide more selective tools for PET imaging in the diagnosis of neurodegenerative disease. They also provide novel biochemical tools for studies of the function of this protein family.

  2. High-resolution mass spectrometry for detecting Acetylcholine in Arabidopsis

    Murata, Jun; Watanabe, Takehiro; Sugahara, Kohtaro; Yamagaki, Tohru; Takahashi, Toshio

    2015-01-01

    Acetylcholine (ACh) was first identified a century ago, and has long been known as a neurotransmitter in animals. However, it has been shown recently that the occurrence of ACh is widespread among various non-animal species including higher plants. Although previous reports suggest that various plant species are capable of responding to exogenously applied ACh, the molecular basis for ACh biosynthesis and regulatory mechanisms mediated by endogenous ACh are largely unclear. This is partly bec...

  3. Cholinergic neurons and terminal fields revealed by immunohistochemistry for the vesicular acetylcholine transporter. II. The peripheral nervous system.

    Schäfer, M K; Eiden, L E; Weihe, E

    1998-05-01

    The peripheral sympathetic and parasympathetic cholinergic innervation was investigated with antibodies directed against the C-terminus of the rat vesicular acetylcholine transporter. Immunohistochemistry for the vesicular acetylcholine transporter resulted in considerably more detailed visualization of cholinergic terminal fields in the peripheral nervous system than reported previously and was well suited to also identify cholinergic perikarya. Vesicular acetylcholine transporter immunoreactivity completely delineated the preganglionic sympathetic terminals in pre- and paravertebral sympathetic ganglia, and in the adrenal medulla as well as postganglionic cholinergic neurons in the paravertebral chain. Cholinergic terminals of sudomotor and vasomotor nerves of skeletal muscle were optimally visualized. Mixed peripheral ganglia, including periprostatic and uterovaginal ganglia, exhibited extensive preganglionic cholinergic innervation of both noradrenergic and cholinergic postganglionic principal neurons which were intermingled in these ganglia. Varicose vesicular acetylcholine transporter-positive fibres and terminals, representing the cranial parasympathetic innervation of the cerebral vasculature, of salivary and lacrimal glands, of the eye, of the respiratory tract and of the upper digestive tract innervated various target structures including seromucous gland epithelium and myoepithelium, respiratory epithelium, and smooth muscle of the tracheobronchial tree. The only macrovascular elements receiving vesicular acetylcholine transporter-positive innervation were the cerebral arteries. The microvasculature throughout the viscera, with the exception of lymphoid tissues, the liver and kidney, received vesicular acetylcholine transporter-positive innervation while the microvasculature of limb and trunk skeletal muscle appeared to be the only relevant somatic target of vesicular acetylcholine transporter innervation. Vesicular acetylcholine transporter

  4. Elimination of the vesicular acetylcholine transporter in the striatum reveals regulation of behaviour by cholinergic-glutamatergic co-transmission.

    Monica S Guzman; Xavier De Jaeger; Sanda Raulic; Souza, Ivana A; Li, Alex X.; Susanne Schmid; Menon, Ravi S.; Gainetdinov, Raul R.; Caron, Marc G.; Robert Bartha; Prado, Vania F.; Prado, Marco A. M.

    2011-01-01

    Cholinergic neurons in the striatum are thought to play major regulatory functions in motor behaviour and reward. These neurons express two vesicular transporters that can load either acetylcholine or glutamate into synaptic vesicles. Consequently cholinergic neurons can release both neurotransmitters, making it difficult to discern their individual contributions for the regulation of striatal functions. Here we have dissected the specific roles of acetylcholine release for striatal-dependent...

  5. Elimination of the vesicular acetylcholine transporter in the striatum reveals regulation of behaviour by cholinergic-glutamatergic co-transmission.

    Guzman, Monica S; De Jaeger, Xavier; Raulic, Sanda; Souza, Ivana A; Li, Alex X; Schmid, Susanne; Menon, Ravi S; Gainetdinov, Raul R; Caron, Marc G; Bartha, Robert; Prado, Vania F; Prado, Marco A M

    2011-11-01

    Cholinergic neurons in the striatum are thought to play major regulatory functions in motor behaviour and reward. These neurons express two vesicular transporters that can load either acetylcholine or glutamate into synaptic vesicles. Consequently cholinergic neurons can release both neurotransmitters, making it difficult to discern their individual contributions for the regulation of striatal functions. Here we have dissected the specific roles of acetylcholine release for striatal-dependent behaviour in mice by selective elimination of the vesicular acetylcholine transporter (VAChT) from striatal cholinergic neurons. Analysis of several behavioural parameters indicates that elimination of VAChT had only marginal consequences in striatum-related tasks and did not affect spontaneous locomotion, cocaine-induced hyperactivity, or its reward properties. However, dopaminergic sensitivity of medium spiny neurons (MSN) and the behavioural outputs in response to direct dopaminergic agonists were enhanced, likely due to increased expression/function of dopamine receptors in the striatum. These observations indicate that previous functions attributed to striatal cholinergic neurons in spontaneous locomotor activity and in the rewarding responses to cocaine are mediated by glutamate and not by acetylcholine release. Our experiments demonstrate how one population of neurons can use two distinct neurotransmitters to differentially regulate a given circuitry. The data also raise the possibility of using VAChT as a target to boost dopaminergic function and decrease high striatal cholinergic activity, common neurochemical alterations in individuals affected with Parkinson's disease. PMID:22087075

  6. Elimination of the vesicular acetylcholine transporter in the striatum reveals regulation of behaviour by cholinergic-glutamatergic co-transmission.

    Monica S Guzman

    2011-11-01

    Full Text Available Cholinergic neurons in the striatum are thought to play major regulatory functions in motor behaviour and reward. These neurons express two vesicular transporters that can load either acetylcholine or glutamate into synaptic vesicles. Consequently cholinergic neurons can release both neurotransmitters, making it difficult to discern their individual contributions for the regulation of striatal functions. Here we have dissected the specific roles of acetylcholine release for striatal-dependent behaviour in mice by selective elimination of the vesicular acetylcholine transporter (VAChT from striatal cholinergic neurons. Analysis of several behavioural parameters indicates that elimination of VAChT had only marginal consequences in striatum-related tasks and did not affect spontaneous locomotion, cocaine-induced hyperactivity, or its reward properties. However, dopaminergic sensitivity of medium spiny neurons (MSN and the behavioural outputs in response to direct dopaminergic agonists were enhanced, likely due to increased expression/function of dopamine receptors in the striatum. These observations indicate that previous functions attributed to striatal cholinergic neurons in spontaneous locomotor activity and in the rewarding responses to cocaine are mediated by glutamate and not by acetylcholine release. Our experiments demonstrate how one population of neurons can use two distinct neurotransmitters to differentially regulate a given circuitry. The data also raise the possibility of using VAChT as a target to boost dopaminergic function and decrease high striatal cholinergic activity, common neurochemical alterations in individuals affected with Parkinson's disease.

  7. Effects of Acetylcholine, Cytochalasin B and Amiprophos methyl on Phloem Transport in Radish (Raphanus sativas)

    Chong-Jun Yang; Zhi-Xi Zhai; Yu-Hai Guo; Peng Gao

    2007-01-01

    We investigated the role of the "sieve tube-companion cell complex" lining the tube periphery, particularly the microfilament and microtubule, in assisting the pushing of phloem sap flow. We made a simple phloem transport system with a living radish plant, in which the conducting channel was exposed for local treatment with chemicals that are effective in modulating protoplasmic movement (acetylcholine, (ACh) a neurotransmitter in animals and insects; cytochalasin B, (CB) a specific inhibitor of many cellular responses that are mediated by microfilament systems and amiprophos-methyl, (APM) a specific inhibitor of many cellular responses that are mediated by microtubule systems). Their effects on phloem transport were estimated by two experimental devices: (i) a comparison of changes in the amount of assimilates in terms of carbohydrates and 14C-labeled photosynthetic production that is left in the leaf blade of treated plants; and (ii) distribution patterns of 14C-labeled leaf assimilates in the phloem transport system. The results indicate that CB and APM markedly inhibited the transfer of photosynthetic product from leaf to root via the leaf vein, while ACh enhanced the transfer of photosynthetic product in low concentrations (5.0×10-4 mol/L) but inhibited it in higher concentrations (2.0×10-3 mol/L) from leaf to root via the leaf vein. Autoradiograph imaging clearly reveals that ACh treatment is more effective than the control, and both CB and APM treatments effectively inhibit the passage of radioactive assimilates. All of the results support the postulation that the peripheral protoplasm in the sieve tube serves not only as a passive semi-permeable membrane, but is also directly involved in phloem transport.

  8. Critical Evaluation of Acetylcholine Determination in Rat Brain Microdialysates using Ion-Pair Liquid Chromatography with Amperometric Detection

    Yvette Michotte

    2008-08-01

    Full Text Available Liquid chromatography with amperometric detection remains the most widely used method for acetylcholine quantification in microdialysis samples. Separation of acetylcholine from choline and other matrix components on a microbore chromatographic column (1 mm internal diameter, conversion of acetylcholine in an immobilized enzyme reactor and detection of the produced hydrogen peroxide on a horseradish peroxidase redox polymer coated glassy carbon electrode, achieves sufficient sensitivity for acetylcholine quantification in rat brain microdialysates. However, a thourough validation within the concentration range required for this application has not been carried out before. Furthermore, a rapid degradation of the chromatographic columns and enzyme systems have been reported. In the present study an ion-pair liquid chromatography assay with amperometric detection was validated and its long-term stability evaluated. Working at pH 6.5 dramatically increased chromatographic stability without a loss in sensitivity compared to higher pH values. The lower limit of quantification of the method was 0.3 nM. At this concentration the repeatability was 15.7%, the inter-day precision 8.7% and the accuracy 103.6%. The chromatographic column was stable over 4 months, the immobilized enzyme reactor up to 2-3 months and the enzyme coating of the amperometric detector up to 1-2 months. The concentration of acetylcholine in 30 μl microdialysates obtained under basal conditions from the hippocampus of freely moving rats was 0.40 ± 0.12 nM (mean ± SD, n = 30. The present method is therefore suitable for acetylcholine determination in rat brain microdialysates.

  9. Evaluation of radioiodinated (-)-o-iodovesamicol as a radiotracer for mapping the vesicular acetylcholine transporter

    We evaluated the potencies of radioiodinated (-)-o-iodovesamicol [(-)-oIV] as a selective vesicular acetylcholine transporter (VAChT) mapping agent. (-)-[125I]oIV exhibited significant accumulation (about 2.8% of the injected dose) in rat brain. The regional brain distribution of radioactivity was similar for both (-)-[125I]oIV and (-)-[3H]vesamicol. The accumulation of (-)-[125I]oIV in the brain was significant reduced by post-administration of unlabeled vesamicol (0.5 μmol/kg-1) and (-)-oIV (0.5 μmol/kg-1). On the other hand, the post-administration of sigma ligands hardly affected the accumulation of (-)-[125I]oIV in the brain. These studies showed that (-)-[125I]oIV, as well as [3H]vesamicol, bound to VAChT with high affinity in the rat brain. Furthermore, (-)-[125I]oIV binding in the ipsilateral cortex to the lesion was significantly reduced by 17.0%, compared with that in the contralateral cortex in a unilateral nucleus basalis magnocellularis (NBM)-lesioned rat. These results suggested that radioiodinated (-)-oIV may potentially be useful for the diagnosis of cholinergic neurodegenerative disorders. (author)

  10. (E)-[125I]-5-AOIBV: a SPECT radioligand for the vesicular acetylcholine transporter

    The premise that, over the course of Alzheimer's disease (AD), changes in the levels of the vesicular acetylcholine transporter (VAChT) occur in parallel with changes to other cholinergic marker proteins provides the basis for the applicability of benzovesamicol derivatives as radioligands for AD studies by single photon emission computed tomography or positron emission tomography. We report the synthesis of enantiopure benzovesamicol derivatives: (R,R) or (S,S)-(E)-2-hydroxy-5-(3-iodoprop-2-en-1-oxy)-3- (4-phenylpiperidino)tetralin [(R,R)-AOIBV: Kd=0.45 nM or (S,S)-5-AOIBV: Kd=4.3 nM] and their corresponding tributyltin precursors for radioiodination. (R,R or S,S)-5-AOIBV was labeled with iodine-125 from their corresponding n-tributyltin precursors. Both compounds were obtained with radiochemical and optical purity greater than 97% and in radiochemical yields ranging 34-36%. To determine if these compounds could provide an advantage when compared to [125I]-iodo benzovesamicol (IBVM), IBVM was also labeled and used as the reference compound in all ex vivo experiments. Ex vivo biodistribution experiments in rats revealed that [125I]-(R,R)-5-AOIBV displayed the most suitable pharmacological profile as the radioactivity distribution corresponded well with the known VAChT brain density. Moreover, pre-injection of vesamicol prevented the uptake of [125I]-(R,R)-5-AOIBV in striatum, cortex and hippocampus, demonstrating selectivity for the VAChT. However, even if time activity curves of [125I]-(R,R)-5-AOIBV confirmed that this compound could be used to visualize the VAChT in vivo, at each point of the kinetic study, [125I]-(R,R)-5-AOIBV showed a lower specific binding compared to [125I]-IBVM. These results made [125I]-( R,R)-5-AOIBV inferior to [125I]-IBVM for the VAChT exploration in vivo

  11. Role of acetylcholine and polyspecific cation transporters in serotonin-induced bronchoconstriction in the mouse

    Koepsell Hermann

    2006-04-01

    Full Text Available Abstract Background It has been proposed that serotonin (5-HT-mediated constriction of the murine trachea is largely dependent on acetylcholine (ACh released from the epithelium. We recently demonstrated that ACh can be released from non-neuronal cells by corticosteroid-sensitive polyspecific organic cation transporters (OCTs, which are also expressed by airway epithelial cells. Hence, the hypothesis emerged that 5-HT evokes bronchoconstriction by inducing release of ACh from epithelial cells via OCTs. Methods We tested this hypothesis by analysing bronchoconstriction in precision-cut murine lung slices using OCT and muscarinic ACh receptor knockout mouse strains. Epithelial ACh content was measured by HPLC, and the tissue distribution of OCT isoforms was determined by immunohistochemistry. Results Epithelial ACh content was significantly higher in OCT1/2 double-knockout mice (42 ± 10 % of the content of the epithelium-denuded trachea, n = 9 than in wild-type mice (16.8 ± 3.6 %, n = 11. In wild-type mice, 5-HT (1 μM caused a bronchoconstriction that slightly exceeded that evoked by muscarine (1 μM in intact bronchi but amounted to only 66% of the response to muscarine after epithelium removal. 5-HT-induced bronchoconstriction was undiminished in M2/M3 muscarinic ACh receptor double-knockout mice which were entirely unresponsive to muscarine. Corticosterone (1 μM significantly reduced 5-HT-induced bronchoconstriction in wild-type and OCT1/2 double-knockout mice, but not in OCT3 knockout mice. This effect persisted after removal of the bronchial epithelium. Immunohistochemistry localized OCT3 to the bronchial smooth muscle. Conclusion The doubling of airway epithelial ACh content in OCT1/2-/- mice is consistent with the concept that OCT1 and/or 2 mediate ACh release from the respiratory epithelium. This effect, however, does not contribute to 5-HT-induced constriction of murine intrapulmonary bronchi. Instead, this activity involves 1 a non

  12. Cholinergic activation of the murine trachealis muscle via non-vesicular acetylcholine release involving low-affinity choline transporters.

    Nassenstein, Christina; Wiegand, Silke; Lips, Katrin S; Li, Guanfeng; Klein, Jochen; Kummer, Wolfgang

    2015-11-01

    In addition to quantal, vesicular release of acetylcholine (ACh), there is also non-quantal release at the motor endplate which is insufficient to evoke postsynaptic responses unless acetylcholinesterase (AChE) is inhibited. We here addressed potential non-quantal release in the mouse trachea by organ bath experiments and (immuno)histochemical methods. Electrical field stimulation (EFS) of nerve terminals elicited tracheal constriction that is largely due to ACh release. Classical enzyme histochemistry demonstrated acetylcholinesterase (AChE) activity in nerve fibers in the muscle and butyrylcholinesterase (BChE) activity in the smooth muscle cells. Acute inhibition of both esterases by eserine significantly raised tracheal tone which was fully sensitive to atropine. This effect was reduced, but not abolished, in AChE, but not in BChE gene-deficient mice. The eserine-induced increase in tracheal tone was unaffected by vesamicol (10(-5)M), an inhibitor of the vesicular acetylcholine transporter, and by corticosterone (10(-4)M), an inhibitor of organic cation transporters. Hemicholinium-3, in low concentrations an inhibitor of the high-affinity choline transporter-1 (CHT1), completely abrogated the eserine effects when applied in high concentrations (10(-4)M) pointing towards an involvement of low-affinity choline transporters. To evaluate the cellular sources of non-quantal ACh release in the trachea, expression of low-affinity choline transporter-like family (CTL1-5) was evaluated by RT-PCR analysis. Even though these transporters were largely abundant in the epithelium, denudation of airway epithelial cells had no effect on eserine-induced tracheal contraction, indicating a non-quantal release of ACh from non-epithelial sources in the airways. These data provide evidence for an epithelium-independent non-vesicular, non-quantal ACh release in the mouse trachea involving low-affinity choline transporters. PMID:26278668

  13. Nicotinic acetylcholine receptor: subunit structure, functional binding sites, and ion transport properties

    The structure of the nicotinic acetylcholine receptor has been highly conserved during animal evolution, and in all the species and tissues studied so far, including mammals, it is a pseudosymmetric, pentameric complex of related subunits with very similar physical properties. All subunits of these nicotinic receptors were derived from a common ancestral gene, probably by way of gene duplications occurring very early in animal evolution. 45 refs., 8 figs., 2 tabs

  14. Evidence that coated vesicles transport acetylcholine receptors to the surface membrane of chick myotubes

    1984-01-01

    Coated vesicles are present in the myoplasm of embryonic chick myotubes grown in vitro. They are most numerous beneath regions of the surface membrane that contain a high density of acetylcholine receptors (AChR). Prolonged exposure of myotubes to saline extract of chick brain increases the number of intracellular AChR and the number of coated vesicles. This suggests that coated vesicles contain AChR, and this hypothesis was tested with horseradish peroxidase-alpha-bungarotoxin (HRP-alpha BTX...

  15. Clinical significance of detection of antibodies to fetal and adult acetylcholine receptors in myasthenia gravis

    Qi-Guang Shi; Zhi-Hong Wang; Xiao-Wei Ma; Da-Qi Zhang; Chun-Sheng Yang; Fu-Dong Shi; Li Yang

    2012-01-01

    Objective To evaluate the frequency,distribution and clinical significance of the antibodies to the fetal and/or adult acetylcholine receptor (AChR) in patients with myasthenia gravis (MG).Methods AChR antibodies were detected by cell-based assay in the serum of ocular MG (OMG) (n =90) and generalized MG (GMG) patients (n =110).The fetaltype (2α∶ β∶ γ∶ δ) and adult-type (2α∶ β∶ ε∶ δ) AChR were used as antigens,and their relevance to disease presentation was assessed.Results The overall frequencies of anti-adult and anti-fetal AChR antibodies were similar in all 200 patients examined,with 14 having serum specific to the AChR-γ subunit,and 22 to the AChR-ε subunit.The overall sensitivity when using the fetal and adult AChR antibodies was higher than that when using the fetal AChR antibody only (P =0.015).Compared with OMG patients,the mean age at disease onset and the positive ratio of antibodies to both isoforms of the AChR were significantly higher in patients who subsequently progressed to GMG.Older patients and patients with both anti-fetal and anti-adult AChR antibodies had a greater risk for developing generalized disease [odds ratio (OR),1.03;95% confidence interval (CI),1.01-1.06 and OR,5.09;95% CI,2.23-11.62].Conclusion Using both fetal-and adulttype AChRs as the antigens may be more sensitive than using either subtype.Patients with serum specific to both isoforms are at a greater risk of progressing to GMG.Patients with disease onset at an advanced age appear to have a higher frequency of GMG conversion.

  16. Automated production of [¹⁸F]VAT suitable for clinical PET study of vesicular acetylcholine transporter.

    Yue, Xuyi; Bognar, Christopher; Zhang, Xiang; Gaehle, Gregory G; Moerlein, Stephen M; Perlmutter, Joel S; Tu, Zhude

    2016-01-01

    Automated production of a promising radiopharmaceutical (-)-(1-(8-(2-[(18)F]fluoroethoxy)-3-hydroxy-1,2,3,4-tetrahydronaphthalen-2-yl)-piperidin-4-yl)(4-fluorophenyl)methanone ([(18)F]VAT) for the vesicular acetylcholine transporter(VAChT) was achieved using a two-step procedure in a current Good Manufacturing Practices fashion. The production of [(18)F]VAT was accomplished in approximately 140 min, with radiochemical yield of ~15.0% (decay corrected), specific activity>111 GBq/µmol, radiochemical purity>99% and mass of VAT ~3.4 μg/batch (n>10). The radiopharmaceutical product meets all quality control criteria for human use, and is suitable for clinical PET studies of VAChT. PMID:26408913

  17. Colorimetric microtiter plate receptor-binding assay for the detection of freshwater and marine neurotoxins targeting the nicotinic acetylcholine receptors

    Rubio, Fernando; Kamp, Lisa; Carpino, Justin; Faltin, Erin; Loftin, Keith A.; Molgó, Jordi; Aráoz, Rómulo

    2014-01-01

    Anatoxin-a and homoanatoxin-a, produced by cyanobacteria, are agonists of nicotinic acetylcholine receptors (nAChRs). Pinnatoxins, spirolides, and gymnodimines, produced by dinoflagellates, are antagonists of nAChRs. In this study we describe the development and validation of a competitive colorimetric, high throughput functional assay based on the mechanism of action of freshwater and marine toxins against nAChRs. Torpedo electrocyte membranes (rich in muscle-type nAChR) were immobilized and stabilized on the surface of 96-well microtiter plates. Biotinylated α-bungarotoxin (the tracer) and streptavidin-horseradish peroxidase (the detector) enabled the detection and quantitation of anatoxin-a in surface waters and cyclic imine toxins in shellfish extracts that were obtained from different locations across the US. The method compares favorably to LC/MS/MS and provides accurate results for anatoxin-a and cyclic imine toxins monitoring. Study of common constituents at the concentrations normally found in drinking and environmental waters, as well as the tolerance to pH, salt, solvents, organic and inorganic compounds did not significantly affect toxin detection. The assay allowed the simultaneous analysis of up to 25 samples within 3.5 h and it is well suited for on-site or laboratory monitoring of low levels of toxins in drinking, surface, and ground water as well as in shellfish extracts.

  18. Molecular imaging of acetylcholine vesicular transporter (VAChT) in demented patients with Alzheimer's disease (AD) by IBVM-SPECT

    Alzheimer's disease (A.D.) is characterized by a premature decline of cholinergic neurons. The 5-I.B.V.M. is an analogue of the Vesamicol that binds to the presynaptic vesicular acetylcholine transporter (VAChT). The exploration of this target should be useful to make an early diagnosis of A.D.. Our first aim was to propose a method of non invasive VAChT quantification according to 5-I.B.V.M. kinetic. 5-I.B.V.M. was injected to four A.D. patients (age = 77 ± 3.9 years and M.M.S.E. = 24.5 ± 1.02) were included in this methodological study. The single-photon emission computed tomography (SPECT) images were obtained at five, 20, 35 and 50 minutes, at then at three, five and 22 hours after intravenous injection of 5-I.B.V.M. (185 MBq). The time activity curves were obtained after SPECT images co registration on a MRI masque. Specific volume of interest (S.P.E. SPEcific) were manually drawn on striatum, pons, thalamus and para-hippocampic gyrus including hippocampus; reference volumes of interest (R.E.F. = REFerence) were drawn on frontal and occipital cerebral cortex. On the basis of uptake kinetic, two modeling approaches were considered: transient equilibrium model for reversible ligand (binding potential (B.P.) (S.P.E. - R.E.F.)/R.E.F.) and Patlak graphical analysis for irreversible tracers (slope given by Ki/DVref where Ki is the influx constant and DVref is the distribution volume of the reference region). We observed an inflection or a steady state of the activity curves in the different regions studied between 250 and 1400 minutes, what seems to confirm that the tracer is little reversible. B.P. values obtained at 21 hours with occipital areas as reference and Ki/DVref values were respectively 4.62 ± 0.42 and 0.07 ± 0.01. The S.P.E. classification according to B.P. and Ki/DVref values were similar to the classification according to the compartmental analysis (Kuhl 1994). The transient equilibrium model with late acquisition seems the more suitable because I

  19. Mice deficient for striatal Vesicular Acetylcholine Transporter (VAChT) display impaired short-term but normal long-term object recognition memory.

    Palmer, Daniel; Creighton, Samantha; Prado, Vania F; Prado, Marco A M; Choleris, Elena; Winters, Boyer D

    2016-09-15

    Substantial evidence implicates Acetylcholine (ACh) in the acquisition of object memories. While most research has focused on the role of the cholinergic basal forebrain and its cortical targets, there are additional cholinergic networks that may contribute to object recognition. The striatum contains an independent cholinergic network comprised of interneurons. In the current study, we investigated the role of this cholinergic signalling in object recognition using mice deficient for Vesicular Acetylcholine Transporter (VAChT) within interneurons of the striatum. We tested whether these striatal VAChT(D2-Cre-flox/flox) mice would display normal short-term (5 or 15min retention delay) and long-term (3h retention delay) object recognition memory. In a home cage object recognition task, male and female VAChT(D2-Cre-flox/flox) mice were impaired selectively with a 15min retention delay. When tested on an object location task, VAChT(D2-Cre-flox/flox) mice displayed intact spatial memory. Finally, when object recognition was tested in a Y-shaped apparatus, designed to minimize the influence of spatial and contextual cues, only females displayed impaired recognition with a 5min retention delay, but when males were challenged with a 15min retention delay, they were also impaired; neither males nor females were impaired with the 3h delay. The pattern of results suggests that striatal cholinergic transmission plays a role in the short-term memory for object features, but not spatial location. PMID:27233822

  20. Effects of proton irradiation of the lumbar intumescence on intra-axonal transport of acetylcholine and cholinergic enzymes in rat sciatic nerve

    The content and intra-axonal transport of acetylcholine (ACh) and the cholinergic enzymes cholineacetyl-transferase (CAT) and ACh-esterase (AChE) in sciatic nerve were investigated in rats following single dose proton irradiation of the lumbar intumescence of the spinal cord with 60 Gy or 200 Gy. One, 7 or 30 days after irradiation nerve-crush operations were performed 12 hours before killing and the levels of ACh and enzyme activities in nerve segments relative to the crushes were estimated by biologic (ACh) to chemical (enzyme) methods. The results indicate that alterations in intra-neuronal dynamics of ACh and related enzymes are not a major cause for the development of neurologic symptoms of the motor system after irradiation, and that descending myelinated axons are of minor importance for the regulation of cholinergic substances in rat motor nerves. (Auth.)

  1. Positron emission tomography imaging of (2R,3R)-5-[18F]fluoroethoxybenzovesamicol in rat and monkey brain: a radioligand for the vesicular acetylcholine transporter

    Introduction: The regional brain distribution of (2R,3R)-5-[18F]fluoroethoxy-benzovesamicol ((-)-[18F]FEOBV), a radioligand for the vesicular acetylcholine transporter (VAChT), was examined in vivo in mice, rats and rhesus monkeys. Methods: Regional brain distributions of (-)-[18F]FEOBV in mice were determined using ex vivo dissection. MicroPET imaging was used to determine the regional brain pharmacokinetics of the radioligand in rat and rhesus monkey brains. Results: In all three species, clear heterogeneous regional brain distributions were obtained, with the rank order of brain tissues (striatum>thalamus>cortex>cerebellum) consistent with the distribution of cholinergic nerve terminals containing the VAChT. Conclusions: (-)-[18F]FEOBV remains a viable candidate for further development as an in vivo imaging agent for positron emission tomography (PET) studies of the VAChT in the human brain.

  2. Ion Transport in Human Pancreatic Duct Epithelium, Capan-1 Cells, Is Regulated by Secretin, VIP, Acetylcholine, and Purinergic Receptors

    Wang, Jing; Novak, Ivana

    2013-01-01

    , purinergic receptors, and determine their effects on ion transport. METHODS: Human adenocarcinoma cell line Capan-1 cells were grown on permeable supports and set in Ussing chambers for electrophysiological recordings. Transepithelial voltage (Vte), resistance, and short-circuit currents (Isc) were measured...

  3. Review of Transportation Mode Detection techniques

    Jacopo Biancat

    2014-10-01

    Full Text Available This paper reviews the works found in the literature in the field of Transportation Mode Detection (TMD which is a subfield of Activity Recognition aiming at indentifying (i.e. classifying the mean of transportation a person is using. The solutions found in literature have different characteristics according to the device for which the solution was tailored (smartphones or other systems such as, e.g., GPS loggers and to the algorithm used for the classification task. This may vary a lot according to the number and type of input used (e.g. accelerations, GPS, maps information or GIS - Geographical Information System information and to the identified classes of transportation mode. These two aspects are the most relevant to consider when evaluating and comparing the accuracies claimed by each work. A comparison of the works is proposed taking into account the characteristics discussed above. In general the accelerometer is the most widely used sensor for TMD applications, as it limits battery consumption and captures relevant features for detecting motion. Indeed a key challenge in TMD is to detect different motorized classes such as bus, car, train and metro because they share common characteristics (such as e.g. the average speed and accelerations which make hard identifying suitable features for the classification algorithm. Identifying the “walk” and “stationary” transportation modes is a simpler task because they are characterized by distinct features.

  4. Towards Indoor Transportation Mode Detection using Mobile Sensing

    Prentow, Thor Siiger; Blunck, Henrik; Kjærgaard, Mikkel Baun; Stisen, Allan

    2015-01-01

    Transportation mode detection is a growing field of research, in which a varietyof methods have been developed for detecting transportation modes foremost foroutdoor travels. It has been employed in application areas such as publictransportation, environmental footprint profiling, and context-aware mobileassistants. For indoor travels the problem of transportation mode detection has receivedcomparatively little attention, even though diverse transportation modes, suchas biking, electric vehic...

  5. Combined α7 nicotinic acetylcholine receptor agonism and partial serotonin transporter inhibition produce antidepressant-like effects in the mouse forced swim and tail suspension tests

    Andreasen, Jesper T; Redrobe, John P; Nielsen, Elsebet Ø

    2012-01-01

    Emerging evidence points to an involvement of nicotinic acetylcholine receptors (nAChRs) in major depression. Nicotine improves symptoms of depression in humans and shows antidepressant-like effects in rodents. Monoamine release is facilitated by nAChR stimulation, and nicotine-evoked serotonin (...

  6. Morphogenetic roles of acetylcholine.

    Lauder, J. M.; Schambra, U B

    1999-01-01

    In the adult nervous system, neurotransmitters mediate cellular communication within neuronal circuits. In developing tissues and primitive organisms, neurotransmitters subserve growth regulatory and morphogenetic functions. Accumulated evidence suggests that acetylcholine, (ACh), released from growing axons, regulates growth, differentiation, and plasticity of developing central nervous system neurons. In addition to intrinsic cholinergic neurons, the cerebral cortex and hippocampus receive ...

  7. Metabolism of acetylcholine in human erythrocytes

    In order to examine the possible role of erythrocyte acetylcholinesterase in the maintenance of membrane phospholipid content and membrane fluidity, experiments were performed to monitor the activity of the enzyme and follow the fate of one of its hydrolytic products, choline. Intact human erythrocytes were incubated with acetylcholine (choline methyl-14C). The incubation resulted in the hydrolysis of acetylcholine to acetate and choline; the reaction was catalyzed by membrane acetylcholinesterase. The studies demonstrate the further metabolism of choline. Experiments were carried out to determine rate of hydrolysis of acetylcholine, uptake of choline, identification of intracellular metabolites of choline, and identification of radiolabeled membrane components. Erythrocytes at a 25% hematocrit were incubated in an isoosmotic bicarbonate buffer pH 7.4, containing glucose, adenosine, streptomycin and penicillin with 0.3 μCi of acetylcholine (choline methyl-14C), for 24 hours. Aliquots of the erythrocyte suspension were taken throughout for analysis. Erythrocytes were washed free of excess substrate, lysed, and the hemolysate was extracted for choline and its metabolites. Blank samples containing incubation buffer and radiolabeled acetylcholine only, and erythrocyte hemolysate extracts were analyzed for choline content, the difference between blank samples and hemolysate extracts was the amount of choline originating from acetylcholine and attributable to acetylcholinesterase activity. The conversion of choline to 14C-betaine is noted after several minutes of incubation; at 30 minutes, more than 80% of 14C-choline is taken up and after several hours, detectable levels of radiolabeled S-adenosylmethionine were present in the hemolysate extract

  8. New Insights on Plant Cell Elongation: A Role for Acetylcholine

    Gian-Pietro Di Sansebastiano

    2014-03-01

    Full Text Available We investigated the effect of auxin and acetylcholine on the expression of the tomato expansin gene LeEXPA2, a specific expansin gene expressed in elongating tomato hypocotyl segments. Since auxin interferes with clathrin-mediated endocytosis, in order to regulate cellular and developmental responses we produced protoplasts from tomato elongating hypocotyls and followed the endocytotic marker, FM4-64, internalization in response to treatments. Tomato protoplasts were observed during auxin and acetylcholine treatments after transient expression of chimerical markers of volume-control related compartments such as vacuoles. Here we describe the contribution of auxin and acetylcholine to LeEXPA2 expression regulation and we support the hypothesis that a possible subcellular target of acetylcholine signal is the vesicular transport, shedding some light on the characterization of this small molecule as local mediator in the plant physiological response.

  9. New insights on plant cell elongation: a role for acetylcholine.

    Di Sansebastiano, Gian-Pietro; Fornaciari, Silvia; Barozzi, Fabrizio; Piro, Gabriella; Arru, Laura

    2014-01-01

    We investigated the effect of auxin and acetylcholine on the expression of the tomato expansin gene LeEXPA2, a specific expansin gene expressed in elongating tomato hypocotyl segments. Since auxin interferes with clathrin-mediated endocytosis, in order to regulate cellular and developmental responses we produced protoplasts from tomato elongating hypocotyls and followed the endocytotic marker, FM4-64, internalization in response to treatments. Tomato protoplasts were observed during auxin and acetylcholine treatments after transient expression of chimerical markers of volume-control related compartments such as vacuoles. Here we describe the contribution of auxin and acetylcholine to LeEXPA2 expression regulation and we support the hypothesis that a possible subcellular target of acetylcholine signal is the vesicular transport, shedding some light on the characterization of this small molecule as local mediator in the plant physiological response. PMID:24642879

  10. Novel acetylcholine and carbamoylcholine analogues

    Hansen, Camilla Petrycer; Jensen, Anders Asbjørn; Christensen, Jeppe K.;

    2008-01-01

    A series of carbamoylcholine and acetylcholine analogues were synthesized and characterized pharmacologically at neuronal nicotinic acetylcholine receptors (nAChRs). Several of the compounds displayed low nanomolar binding affinities to the alpha 4beta 2 nAChR and pronounced selectivity for this ...

  11. Contamination detection device for radioactive material transporting device

    The present invention provides a device for detecting leakage of radioactive materials and clogging of a vial in a radioactive material transporting device. Namely, a transporting tube pneumatically transports the vial containing a sample of radioactive materials. A fine flow tube is laid in adjacent with and along the transporting tube. A pump flows a detection liquid prepared by a preparation device to the fine flow tube. A flow-cell type spectrophotometer is disposed to the fine flow tube. The detection liquid is preferably containing elements having a valency changeable by undergoing radiation irradiation, which is a type used, for example, for a Fricke dosimeter. With such a constitution, the position of the radioactive contamination of the inside of the pneumatic tube and clogging of a vial can be detected only by flowing radiation sensitive detection liquid to the fine flow tube. In addition, the detection liquid is not activated only changing the valency of the contained elements. (N.H.)

  12. Community core detection in transportation networks.

    De Leo, Vincenzo; Santoboni, Giovanni; Cerina, Federica; Mureddu, Mario; Secchi, Luca; Chessa, Alessandro

    2013-10-01

    This work analyzes methods for the identification and the stability under perturbation of a territorial community structure with specific reference to transportation networks. We considered networks of commuters for a city and an insular region. In both cases, we have studied the distribution of commuters' trips (i.e., home-to-work trips and vice versa). The identification and stability of the communities' cores are linked to the land-use distribution within the zone system, and therefore their proper definition may be useful to transport planners. PMID:24229228

  13. Community core detection in transportation networks

    De Leo, Vincenzo; Santoboni, Giovanni; Cerina, Federica; Mureddu, Mario; Secchi, Luca; Chessa, Alessandro

    2013-10-01

    This work analyzes methods for the identification and the stability under perturbation of a territorial community structure with specific reference to transportation networks. We considered networks of commuters for a city and an insular region. In both cases, we have studied the distribution of commuters’ trips (i.e., home-to-work trips and vice versa). The identification and stability of the communities’ cores are linked to the land-use distribution within the zone system, and therefore their proper definition may be useful to transport planners.

  14. Community core detection in transportation networks

    De Leo, Vincenzo; Cerina, Federica; Mureddu, Mario; Secchi, Luca; Chessa, Alessandro

    2013-01-01

    This work analyzes methods for the identification and the stability under perturbation of a territorial community structure with specific reference to transportation networks. We considered networks of commuters for a city and an insular region. In both cases, we have studied the distribution of commuters' trips (i.e., home-to-work trips and viceversa). The identification and stability of the communities' cores are linked to the land-use distribution within the zone system, and therefore their proper definition may be useful to transport planners.

  15. Community core detection in transportation networks

    Leo, Vincenzo; Santoboni, Giovanni; Cerina, Federica; Mureddu, Mario; Secchi, Luca; Chessa, Alessandro

    2013-01-01

    This work analyses methods for the identification and the stability under perturbation of a territorial community structure with specific reference to transportation networks. We considered networks of commuters for a city and an insular region. In both cases, we have studied the distribution of commuters' trips (i.e., home-to-work trips and viceversa). The identification and stability of the communities' cores are linked to the land-use distribution within the zone system, and therefore thei...

  16. Cholinergic neurotransmission in human corpus cavernosum. II. Acetylcholine synthesis

    Physiological and histochemical evidence indicates that cholinergic nerves may participate in mediating penile erection. Acetylcholine synthesis and release was studied in isolated human corporal tissue. Human corpus cavernosum incubated with [3H]choline accumulated [3H]choline and synthesized [3H]acethylcholine in an concentration-dependent manner. [3H]Acetylcholine accumulation by the tissue was inhibited by hemicholinium-3, a specific antagonist of the high-affinity choline transport in cholinergic nerves. Transmural electrical field stimulation caused release of [3H]acetylcholine which was significantly diminished by inhibiting neurotransmission with calcium-free physiological salt solution or tetrodotoxin. These observations provide biochemical and physiological evidence for the existence of cholinergic innervation in human corpus cavernosum

  17. PCR detection of groundwater bacteria associated with colloidal transport

    Colloidal transport may increase the amount of contaminant material than that which could be transported by water flow alone. The role of colloids in groundwater contaminant transport is complicated and may involve many different processes, including sorption of elements onto colloidal particles, coagulation/dissolution, adsorption onto solid surfaces, filtration, and migration. Bacteria are known to concentrate minerals and influence the transport of compounds in aqueous environments and may also serve as organic colloids, thereby influencing subsurface transport of radionuclides and other contaminants. The initial phase of the project consisted of assembling a list of bacteria capable of sequestering or facilitating mineral transport. The development and optimization of the PCR amplification assay for the detection of the organisms of interest, and the examination of regional groundwaters for those organisms, are presented for subsequent research

  18. PCR detection of groundwater bacteria associated with colloidal transport

    Cruz-Perez, P.; Stetzenbach, L.D.; Alvarez, A.J.

    1996-02-29

    Colloidal transport may increase the amount of contaminant material than that which could be transported by water flow alone. The role of colloids in groundwater contaminant transport is complicated and may involve many different processes, including sorption of elements onto colloidal particles, coagulation/dissolution, adsorption onto solid surfaces, filtration, and migration. Bacteria are known to concentrate minerals and influence the transport of compounds in aqueous environments and may also serve as organic colloids, thereby influencing subsurface transport of radionuclides and other contaminants. The initial phase of the project consisted of assembling a list of bacteria capable of sequestering or facilitating mineral transport. The development and optimization of the PCR amplification assay for the detection of the organisms of interest, and the examination of regional groundwaters for those organisms, are presented for subsequent research.

  19. Immunisation with Torpedo acetylcholine receptor.

    Elfman, L

    1984-01-01

    Acetylcholine mediates the transfer of information between neurons in the electric organ of, for example, Torpedo as well as in vertebrate skeletal muscle. The nicotinic acetylcholine receptor complex translates the binding of acetylcholine into ion permeability changes. This leads to an action potential in the muscle fibre. The nicotinic acetylcholine receptor protein has been purified from Torpedo by use of affinity chromatography. The receptor is an intrinsic membrane glycoprotein composed of five polypeptide chains. When various animals are immunised with the receptor they demonstrate clinical signs of severe muscle weakness coincident with high antibody titres in their sera. The symptoms resemble those found in the autoimmune neuromuscular disease myasthenia gravis in humans. This animal model has constituted a unique model for studying autoimmune diseases. This paper reviews some of the work using Torpedo acetylcholine receptor in order to increase the understanding of the motor nervous system function and myasthenia gravis. It is now known that the nicotinic acetylcholine receptor protein is the antigen involved in myasthenia gravis. The mechanism of immune damage involves a direct block of the receptor function. This depends on the presence of antibodies which crosslink the postsynaptic receptors leading to their degradation. The questions to be answered in the future are; (a) what initiates or triggers the autoimmune response, (b) how do the antibodies cause the symptoms--is there a steric hindrance of the interaction of acetylcholine and the receptor, (c) why is there not a strict relationship between antibody titre and severity of symptoms, and (d) why are some muscles affected and other spared? With help of the experimental model, answers to these questions may result in improved strategies for the treatment of the autoimmune disease myasthenia gravis. PMID:6097937

  20. Transports Regulators of Networks with Junctions Detected by Durations Functions

    Aubin, Jean-Pierre

    2013-01-01

    This study advocates a mathematical framework of ''transport relations'' on a network. They single out a subset of ''traffic states'' described by time, duration, position and other traffic attributes (called ''monads'' for short). Duration evolutions are non-negative, decreasing toward zero for incoming durations, increasing from zero for outgoing durations, allowing the detection of ''junction states'' defined as traffic states with ''zero duration''. A ''junction relation'' (crossroads, sy...

  1. Cocaine inhibition of nicotinic acetylcholine receptors influences dopamine release

    Alexandra eAcevedo-Rodriguez; Lifen eZhang; Fuwen eZhou; Suzhen eGong; Howard eGu; Mariella eDe Biasi; Fu-Ming eZhou; Dani, John A.

    2014-01-01

    Nicotinic acetylcholine receptors (nAChRs) potently regulate dopamine (DA) release in the striatum and alter cocaine’s ability to reinforce behaviors. Since cocaine is a weak nAChR inhibitor, we hypothesized that cocaine may alter DA release by inhibiting the nAChRs in DA terminals in the striatum and thus contribute to cocaine's reinforcing properties primarily associated with the inhibition of DA transporters. We found that biologically relevant concentrations of cocaine can mildly inhibit...

  2. Tubular crystals of acetylcholine receptor

    1984-01-01

    Well-ordered tubular crystals of acetylcholine receptor were obtained from suspensions of Torpedo marmorata receptor-rich vesicles. They are composed of pairs of oppositely oriented molecules arranged on the surface lattice with the symmetry of the plane group p2 (average unit cell dimensions: a = 90 A, b = 162 A, gamma = 117 degrees). The receptor in this lattice has an asymmetric distribution of mass around its perimeter, yet a regular pentagonal shape; thus its five transmembrane subunits ...

  3. Acetylcholine functionally reorganizes neocortical microcircuits

    Runfeldt, Melissa J.; Sadovsky, Alexander J.; MacLean, Jason N.

    2014-01-01

    Sensory information is processed and transmitted through the synaptic structure of local cortical circuits, but it is unclear how modulation of this architecture influences the cortical representation of sensory stimuli. Acetylcholine (ACh) promotes attention and arousal and is thought to increase the signal-to-noise ratio of sensory input in primary sensory cortices. Using high-speed two-photon calcium imaging in a thalamocortical somatosensory slice preparation, we recorded action potential...

  4. Enzyme-linked DNA dendrimer nanosensors for acetylcholine

    Walsh, Ryan; Morales, Jennifer M.; Skipwith, Christopher G.; Ruckh, Timothy T.; Clark, Heather A.

    2015-10-01

    It is currently difficult to measure small dynamics of molecules in the brain with high spatial and temporal resolution while connecting them to the bigger picture of brain function. A step towards understanding the underlying neural networks of the brain is the ability to sense discrete changes of acetylcholine within a synapse. Here we show an efficient method for generating acetylcholine-detecting nanosensors based on DNA dendrimer scaffolds that incorporate butyrylcholinesterase and fluorescein in a nanoscale arrangement. These nanosensors are selective for acetylcholine and reversibly respond to levels of acetylcholine in the neurophysiological range. This DNA dendrimer architecture has the potential to overcome current obstacles to sensing in the synaptic environment, including the nanoscale size constraints of the synapse and the ability to quantify the spatio-temporal fluctuations of neurotransmitter release. By combining the control of nanosensor architecture with the strategic placement of fluorescent reporters and enzymes, this novel nanosensor platform can facilitate the development of new selective imaging tools for neuroscience.

  5. Dose protocols of acetylcholine test in Chinese

    向定成; 龚志华; 何建新; 洪长江; 邱建; 马骏

    2004-01-01

    @@ Acetylcholine test has been widely used clinically in several countries as a practical test provoking coronary artery spasm.1-3 Although it has also been launched recently in a few hospitals in China, the dose protocol for acetylcholine test used in these hospitals were from abroad.4,5 This study was aimed at developing a dose protocol for acetylcholine test suitable for Chinese people.

  6. Acetylcholine in plants: presence, metabolism and mechanism of action

    Tretyn, Andrzej; Kendrick, Richard E.

    1991-01-01

    Acetylcholine (ACh) has been detected in representatives of many taxonomic groups throughout the plant kingdom. The site of its synthesis in plants is probably young leaves. In some plant species choline acetyltransferase (CHAT) activity has been found. This enzyme showing properties similar to animal CHAT, probably participates in ACh synthesis from its precursors, choline and acetyl-Coenzyme A. Acetylcholinesterase (ACHE) activity has also been found in many plant tissues. Th...

  7. Nicotinic Acetylcholine Receptor (nAChR Dependent Chorda Tympani Taste Nerve Responses to Nicotine, Ethanol and Acetylcholine.

    Zuo Jun Ren

    Full Text Available Nicotine elicits bitter taste by activating TRPM5-dependent and TRPM5-independent but neuronal nAChR-dependent pathways. The nAChRs represent common targets at which acetylcholine, nicotine and ethanol functionally interact in the central nervous system. Here, we investigated if the nAChRs also represent a common pathway through which the bitter taste of nicotine, ethanol and acetylcholine is transduced. To this end, chorda tympani (CT taste nerve responses were monitored in rats, wild-type mice and TRPM5 knockout (KO mice following lingual stimulation with nicotine free base, ethanol, and acetylcholine, in the absence and presence of nAChR agonists and antagonists. The nAChR modulators: mecamylamine, dihydro-β-erythroidine, and CP-601932 (a partial agonist of the α3β4* nAChR, inhibited CT responses to nicotine, ethanol, and acetylcholine. CT responses to nicotine and ethanol were also inhibited by topical lingual application of 8-chlorophenylthio (CPT-cAMP and loading taste cells with [Ca2+]i by topical lingual application of ionomycin + CaCl2. In contrast, CT responses to nicotine were enhanced when TRC [Ca2+]i was reduced by topical lingual application of BAPTA-AM. In patch-clamp experiments, only a subset of isolated rat fungiform taste cells exposed to nicotine responded with an increase in mecamylamine-sensitive inward currents. We conclude that nAChRs expressed in a subset of taste cells serve as common receptors for the detection of the TRPM5-independent bitter taste of nicotine, acetylcholine and ethanol.

  8. Effect of organophosphorus insecticides on phosphorylation of the M2 muscarinic acetylcholine receptor

    Shuyin Li; Liming Zou; Carry Pope

    2008-01-01

    BACKGROUND: Organophosphorus insecticides may promote the accumulation of acetylcholine at synapses and the neuromuscular junction by inhibiting acetylcholinesterase activity to cause disturbance of neural signal conduction and induce a toxic reaction. Organophosphorus insecticides may act on M2 muscarinic acetylcholine receptors, whose combination with G proteins is regulated by phosphorylation of G protein-coupled receptor kinase 2.OBJECTIVE: To investigate the effects of organophosphorus insecticides on the phosphorylation of G protein-coupled receptor kinase 2-mediated M2 muscarinic acetylcholine receptors and to reveal other possible actions of organophosphorus insecticides.DESIGN, TIME AND SETTING: An observational study, which was performed in the Central Laboratory of Shenyang Medical College, and Department of Physiological Sciences, College of Veterinary Medicine, Oklahoma State University from June 2002 to December 2004.METHODS: The M2 muscarinic acetylcholine receptor was extracted and purified from pig brain using affinity chromatography. Subsequently, the purified M2 muscarinic acetylcholine receptor, G protein-coupled receptor kinase 2, and [OP32] ATP were incubated with different concentrations of paraoxon and chlorpyrifos oxon together. The mixture then underwent polyacrylamide gel electrophoresis, and the gel film was dried and radioactively autographed to detect phosphorylation of the M2 muscarinic acetylcholine receptor. Finally, the radio-labeled phosphorylated M2 receptor protein band was excised for counting with an isotope liquid scintillation counter.MAIN OUTCOME MEASURES: Effects of chlorpyrifos oxon, paraoxon, chlorpyrifos, and parathion in different concentrations on the phosphorylation of the M2 muscarinic acetylcholine receptor; effects of chlorpyrifos oxon on the phosphorylation of the adrenergic receptor.CONCLUSION: Different kinds of organophosphorus insecticides have different effects on the phosphorylation of the G protein

  9. Acoustic leak-detection system for railroad transportation security

    Womble, P. C.; Spadaro, J.; Harrison, M. A.; Barzilov, A.; Harper, D.; Hopper, L.; Houchins, E.; Lemoff, B.; Martin, R.; McGrath, C.; Moore, R.; Novikov, I.; Paschal, J.; Rogers, S.

    2007-04-01

    Pressurized rail tank cars transport large volumes of volatile liquids and gases throughout the country, much of which is hazardous and/or flammable. These gases, once released in the atmosphere, can wreak havoc with the environment and local populations. We developed a system which can non-intrusively and non-invasively detect and locate pinhole-sized leaks in pressurized rail tank cars using acoustic sensors. The sound waves from a leak are produced by turbulence from the gas leaking to the atmosphere. For example, a 500 μm hole in an air tank pressurized to 689 kPa produces a broad audio frequency spectrum with a peak near 40 kHz. This signal is detectable at 10 meters with a sound pressure level of 25 dB. We are able to locate a leak source using triangulation techniques. The prototype of the system consists of a network of acoustic sensors and is located approximately 10 meters from the center of the rail-line. The prototype has two types of acoustic sensors, each with different narrow frequency response band: 40 kHz and 80 kHz. The prototype is connected to the Internet using WiFi (802.11g) transceiver and can be remotely operated from anywhere in the world. The paper discusses the construction, operation and performance of the system.

  10. neu-VISION: an explosives detection system for transportation security

    Warman, Kieffer; Penn, David

    2008-04-01

    Terrorists were targeting commercial airliners long before the 9/11 attacks on the World Trade Center and the Pentagon. Despite heightened security measures, commercial airliners remain an attractive target for terrorists, as evidenced by the August 2006 terrorist plot to destroy as many as ten aircraft in mid-flight from the United Kingdom to the United States. As a response to the security threat air carriers are now required to screen 100-percent of all checked baggage for explosives. The scale of this task is enormous and the Transportation Security Administration has deployed thousands of detection systems. Although this has resulted in improved security, the performance of the installed systems is not ideal. Further improvements are needed and can only be made with new technologies that ensure a flexible Concept of Operations and provide superior detection along with low false alarm rates and excellent dependability. To address security needs Applied Signal Technology, Inc. is developing an innovative and practical solution to meet the performance demands of aviation security. The neu-VISION TM system is expected to provide explosives detection performance for checked baggage that both complements and surpasses currently deployed performance. The neu-VISION TM system leverages a 5 year R&D program developing the Associated Particle Imaging (API) technique; a neutron based non-intrusive material identification and imaging technique. The superior performance afforded by this neutron interrogation technique delivers false alarm rates much lower than deployed technologies and "sees through" dense, heavy materials. Small quantities of explosive material are identified even in the cluttered environments.

  11. Nicotinic acetylcholine receptors mediate lung cancer growth

    PaulDGardner

    2013-09-01

    Full Text Available Ion channels modulate ion flux across cell membranes, activate signal transduction pathways, and influence cellular transport – vital biological functions that are inexorably linked to cellular processes that go awry during carcinogenesis. Indeed, deregulation of ion channel function has been implicated in cancer-related phenomena such as unrestrained cell proliferation and apoptotic evasion. As the prototype for ligand-gated ion channels, nicotinic acetylcholine receptors (nAChRs have been extensively studied in the context of neuronal cells but accumulating evidence also indicate a role for nAChRs in carcinogenesis. Recently, variants in the nAChR genes CHRNA3, CHRNA5, and CHRNB4 have been implicated in nicotine dependence and lung cancer susceptibility. Here, we silenced the expression of these three genes to investigate their function in lung cancer. We show that these genes are necessary for the viability of small cell lung carcinomas (SCLC, the most aggressive type of lung cancer. Furthermore, we show that nicotine promotes SCLC cell viability whereas an α3β4-selective antagonist, α-conotoxin AuIB, inhibits it. Our findings posit a mechanism whereby signaling via α3/α5/β4-containing nAChRs promotes lung carcinogenesis.

  12. Optical detection of spin transport in non-magnetic metals

    Fohr, Frederik; Kaltenborn, Steffen; Hamrle, Jaroslav; Schultheiss, Helmut; Serga, Alexander A.; Schneider, Hans Christian; Hillebrands, Burkard [Fachbereich Physik, Landesforschungszentrum OPTIMAS, TU Kaiserslautern, 67663 Kaiserslautern (Germany); Fukuma, Yasuhiro; Wang, Le; Otani, YoshiChika [ASI RIKEN, ISSP, University of Tokyo (Japan)

    2011-07-01

    We detect the dynamic magnetization in non-magnetic metal wedges, composed of silver, copper and platinum and grown on top of a Ni{sub 80}Fe{sub 20} layer. The Ni{sub 80}Fe{sub 20} layer is excited externally by the RF field of a coplanar waveguide (CPW), and generates the dynamic magnetization in the wedge layer via the spin pumping effect. The inelastically scattered light is collected as a function of the local wedge thickness and analysed by Brillouin light scattering (BLS) microscopy. The BLS signal originates from the metal wedges due to inelastic scattering from the spin polarization as well as from the magnetic layer below the wedge. To separate both contributions of the signal experimentally, reference samples are prepared with an interlayer between Ni{sub 81}Fe{sub 19} and the respective metal wedge to block the spin pumping. By comparing the experimental results to a macroscopic spin-transport model we determine the transverse relaxation time of the pumped spin current which is much smaller than the longitudinal relaxation time.

  13. Vadose Zone Sampling Methods for Detection of Preferential Pesticides Transport

    Peranginangin, N.; Richards, B. K.; Steenhuis, T. S.

    2003-12-01

    Leaching of agricultural applied chemicals through the vadose zone is a major cause for the occurrence of agrichemicals in groundwater. Accurate soil water sampling methods are needed to ensure meaningful monitoring results, especially for soils that have significant preferential flow paths. The purpose of this study was to assess the capability and the effectiveness of various soil water sampling methods in detecting preferential transport of pesticides in a strongly-structured silty clay loam (Hudson series) soil. Soil water sampling devices tested were wick pan and gravity pan lysimeters, tile lines, porous ceramic cups, and pipe lysimeters; all installed at 45 to105 cm depth below the ground surface. A reasonable worse-case scenario was tested by applying a simulated rain storm soon after pesticides were sprayed at agronomic rates. Herbicides atrazine (6-chloro-N2-ethyl-N4-isopropyl-1,3,5-triazine-2,4-diamine) and 2,4-D (2,4-dichloro-phenoxyacetic acid) were chosen as model compounds. Chloride (KCl) tracer was used to determine spatial and temporal distribution of non-reactive solute and water as well as a basis for determining the retardation in pesticides movement. Results show that observed pesticide mobility was much greater than would be predicted by uniform flow. Under relatively high soil moisture conditions, gravity and wick pan lysimeters had comparably good collection efficiencies, whereas the wick samplers had an advantage over gravity driven sampler when the soil moisture content was below field capacity. Pipe lysimeters had breakthrough patterns that were similar to pan samplers. At small plot scale, tile line samplers tended to underestimate solute concentration because of water dilution around the samplers. The use of porous cup samplers performed poorly because of their sensitivity to local profile characteristics: only by chance can they intercept and sample the preferential flow paths that are critical to transport. Wick sampler had the least

  14. Early fluorescence signals detect transitions at mammalian serotonin transporters.

    Li, Ming; Lester, Henry A.

    2002-01-01

    The mammalian serotonin transporters rSERT or hSERT were expressed in oocytes and labeled with sulforhodamine-MTS. The endogenous Cys-109 residue contributes most of the signal, and the labeled transporter shows normal function. The SERT fluorescence decreases in the presence of 5-HT and also depends on the inorganic substrates of SERT. The fluorescence also increases with membrane depolarization. During voltage-jump experiments, fluorescence relaxations show little inactivation or history de...

  15. Using Smart Phone Sensors to Detect Transportation Modes

    Hao Xia; Yanyou Qiao; Jun Jian; Yuanfei Chang

    2014-01-01

    The proliferation of mobile smart devices has led to a rapid increase of location-based services, many of which are amassing large datasets of user trajectory information. Unfortunately, current trajectory information is not yet sufficiently rich to support classification of user transportation modes. In this paper, we propose a method that employs both the Global Positioning System and accelerometer data from smart devices to classify user outdoor transportation modes. The classified modes i...

  16. Uptake of 3H-choline and synthesis of 3H-acetylcholine by human penile corpus cavernosum

    The neuroeffectors which relax penile smooth muscle and lead to erection are unknown; physiological studies of human corpus cavernosum, in vitro, have suggested a significant role of cholinergic neurotransmission. To further characterize the importance of cholinergic nerves, biopsies of human corpus cavernosum were obtained at the time of penile prosthesis implantation. Tissues were incubated in 3H-choline (10-5M, 80 Ci/mmol) in oxygenated physiological salt solution at 370C, pH 7.4 for 1 hour. Radiolabelled compounds were extracted with perchloric acid (0.4 M) and acetylcholine and choline were separated by HPLC; 14C-acetylcholine was used as internal standard. 3H-choline was accumulated by the tissues (20 +/- 1.9 fmol/mg), and 3H-acetylcholine was synthesized (4.0 +/- 1.1 fmol/mg). In control experiments, heating of the tissue blocked synthesis of 3H-acetylcholine. Inhibition of high affinity choline transport by hemicholinium-3 (10-5M) diminished tissue accumulation of 3H-choline and significantly reduced the synthesis of 3H-acetylcholine (0.5 +/ 0.2 fmol/mg, p < 0.05). These results provide direct evidence of neuronal accumulation of choline and enzymatic conversion to acetylcholine in human corpus cavernosum. Taken together with the physiological studies, it can be concluded that cholinergic neurotransmission in human corpus cavernosum plays a role in penile erection

  17. Acetylcholine synthesis and possible functions during sea urchin development

    C Angelini

    2009-06-01

    Full Text Available Cholinergic neurotransmitter system molecules were found to play a role during fertilisation and early cell cycles of a large number of invertebrate and vertebrate organisms. In this study, we investigated the presence and possible function of choline acetyltransferase (ChAT, the biosynthetic enzyme of acetylcholine in gametes of the sea urchin, Paracentrotus lividus, through localisation and functional studies. ChAT-like molecules were detected in oocytes, mature eggs and zygotes with indirect immunofluorescence methods. Positive immunoreactivity was found in the ovarian egg cytoplasm and surface as well as at the zygote surface. This suggests the eggs' capacity to autonomously synthesise acetylcholine (ACh, the signal molecule of the cholinergic system. Acetylcholinesterase (AChE, the lytic enzyme of acetylcholine was also found in ovarian eggs, with a similar distribution; however, it disappeared after fertilisation. Ultrastructural ChAT localisation in sperms, which was carried out with the immuno-gold method, showed immunoreactivity in the acrosome of unreacted sperms and at the head surface of reacted sperms. In order to verify a functional role of ACh during fertilization and sea urchin development, in vivo experiments were performed. Exposure of the eggs before fertilisation to 1 mM ACh + 1 ?M eserine caused an incomplete membrane depolarisation and consequently enhanced polyspermy, while lower concentrations of ACh caused developmental anomalies. The exposure of zygotes to 0,045 AChE Units/mL of sea water caused developmental anomalies as well, in 50% of the embryos. Altogether, these findings and other previously obtained results, suggest that the cholinergic system may subserve two different tasks during development, according to which particular type of ACh receptor is active during each temporal window. The first function, taking place in the course of fertilisation is a result of autonomously synthesised ACh in sperms, while the

  18. Towards Indoor Transportation Mode Detection using Mobile Sensing

    Prentow, Thor Siiger; Blunck, Henrik; Kjærgaard, Mikkel Baun;

    2015-01-01

    ) such methods at a large hospital complex. The evaluation presented here utilizes Wi-Fi and accelerometer data collected through smartphones carried by several hospital workers throughout four days of work routines. The results show that the methods can distinguish between six common modes of transportation...

  19. Parazoanthoxanthin A blocks Torpedo nicotinic acetylcholine receptors.

    Rozman, Klara Bulc; Araoz, Romulo; Sepcić, Kristina; Molgo, Jordi; Suput, Dusan

    2010-09-01

    Nicotinic acetylcholine receptors are implicated in different nervous system-related disorders, and their modulation could improve existing therapy of these diseases. Parazoanthoxanthin A (ParaA) is a fluorescent pigment of the group of zoanthoxanthins. Since it is a potent acetylcholinesterase inhibitor, it may also bind to nicotinic acetylcholine receptors (nAChRs). For this reason its effect on Torpedo nAChR (alpha1(2)betagammadelta) transplanted to Xenopus laevis oocytes was evaluated, using the voltage-clamp technique. ParaA dose-dependently reduced the acetylcholine-induced currents. This effect was fully reversible only at lower concentrations. ParaA also reduced the Hill coefficient and the time to peak current, indicating a channel blocking mode of action. On the other hand, the combined effect of ParaA and d-tubocurarine (d-TC) on acetylcholine-induced currents exhibited only partial additivity, assuming a competitive mode of action of ParaA on nAChR. These results indicate a dual mode of action of ParaA on the Torpedo AChR. PMID:20230806

  20. Allosteric Modulation of Muscarinic Acetylcholine Receptors

    Jakubík, Jan; El-Fakahany, E. E.

    2010-01-01

    Roč. 3, č. 9 (2010), s. 2838-2860. ISSN 1424-8247 R&D Projects: GA ČR GA305/09/0681 Institutional research plan: CEZ:AV0Z50110509 Keywords : muscarinic acetylcholine receptors * allosteric modulation * Alzheimer ´s disease Subject RIV: CE - Biochemistry

  1. Acetylcholine affects osteocytic MLO-Y4 cells via acetylcholine receptors.

    Ma, Yuanyuan; Li, Xianxian; Fu, Jing; Li, Yue; Gao, Li; Yang, Ling; Zhang, Ping; Shen, Jiefei; Wang, Hang

    2014-03-25

    The identification of the neuronal control of bone remodeling has become one of the many significant recent advances in bone biology. Cholinergic activity has recently been shown to favor bone mass accrual by complex cellular regulatory networks. Here, we identified the gene expression of the muscarinic and nicotinic acetylcholine receptors (m- and nAChRs) in mice tibia tissue and in osteocytic MLO-Y4 cells. Acetylcholine, which is a classical neurotransmitter and an osteo-neuromediator, not only influences the mRNA expression of the AChR subunits but also significantly induces the proliferation and viability of osteocytes. Moreover, acetylcholine treatment caused the reciprocal regulation of RANKL and OPG mRNA expression, which resulted in a significant increase in the mRNA ratio of RANKL:OPG in osteocytes via acetylcholine receptors. The expression of neuropeptide Y and reelin, which are two neurogenic markers, was also modulated by acetylcholine via m- and nAChRs in MLO-Y4 cells. These results indicated that osteocytic acetylcholine receptors might be a new valuable mediator for cell functions and even for bone remodeling. PMID:24508663

  2. The Diversity and Scale Matter: Ubiquitous Transportation Mode Detection using Single Cell Tower Information

    AbdelAziz, Ali Mohamed; Youssef, Moustafa

    2015-01-01

    Detecting the transportation mode of a user is important for a wide range of applications. While a number of recent systems addressed the transportation mode detection problem using the ubiquitous mobile phones, these studies either leverage GPS, the inertial sensors, and/or multiple cell towers information. However, these different phone sensors have high energy consumption, limited to a small subset of phones (e.g. high-end phones or phones that support neighbouring cell tower information),...

  3. Using smart phone sensors to detect transportation modes.

    Xia, Hao; Qiao, Yanyou; Jian, Jun; Chang, Yuanfei

    2014-01-01

    The proliferation of mobile smart devices has led to a rapid increase of location-based services, many of which are amassing large datasets of user trajectory information. Unfortunately, current trajectory information is not yet sufficiently rich to support classification of user transportation modes. In this paper, we propose a method that employs both the Global Positioning System and accelerometer data from smart devices to classify user outdoor transportation modes. The classified modes include walking, bicycling, and motorized transport, in addition to the motionless (stationary) state, for which we provide new depth analysis. In our classification, stationary mode has two sub-modes: stay (remaining in the same place for a prolonged time period; e.g., in a parked vehicle) and wait (remaining at a location for a short period; e.g., waiting at a red traffic light). These two sub-modes present different semantics for data mining applications. We use support vector machines with parameters that are optimized for pattern recognition. In addition, we employ ant colony optimization to reduce the dimension of features and analyze their relative importance. The resulting classification system achieves an accuracy rate of 96.31% when applied to a dataset obtained from 18 mobile users. PMID:25375756

  4. Using Smart Phone Sensors to Detect Transportation Modes

    Hao Xia

    2014-11-01

    Full Text Available The proliferation of mobile smart devices has led to a rapid increase of location-based services, many of which are amassing large datasets of user trajectory information. Unfortunately, current trajectory information is not yet sufficiently rich to support classification of user transportation modes. In this paper, we propose a method that employs both the Global Positioning System and accelerometer data from smart devices to classify user outdoor transportation modes. The classified modes include walking, bicycling, and motorized transport, in addition to the motionless (stationary state, for which we provide new depth analysis. In our classification, stationary mode has two sub-modes: stay (remaining in the same place for a prolonged time period; e.g., in a parked vehicle and wait (remaining at a location for a short period; e.g., waiting at a red traffic light. These two sub-modes present different semantics for data mining applications. We use support vector machines with parameters that are optimized for pattern recognition. In addition, we employ ant colony optimization to reduce the dimension of features and analyze their relative importance. The resulting classification system achieves an accuracy rate of 96.31% when applied to a dataset obtained from 18 mobile users.

  5. Application of neutron/gamma transport codes for the design of explosive detection systems

    Applications of neutron and gamma transport codes to the design of nuclear techniques for detecting concealed explosives material are discussed. The methodology of integrating radiation transport computations in the development, optimization and analysis phases of these new technologies is discussed. Transport and Monte Carlo codes are used for proof of concepts, guide the system integration, reduce the extend of experimental program and provide insight into the physical problem involved. The paper concentrates on detection techniques based on thermal and fast neutron interactions in the interrogated object. (authors). 6 refs., 1 tab., 5 figs

  6. Conflict Detection and Resolution for Future Air Transportation Management

    Krozel, Jimmy; Peters, Mark E.; Hunter, George

    1997-01-01

    With a Free Flight policy, the emphasis for air traffic control is shifting from active control to passive air traffic management with a policy of intervention by exception. Aircraft will be allowed to fly user preferred routes, as long as safety Alert Zones are not violated. If there is a potential conflict, two (or more) aircraft must be able to arrive at a solution for conflict resolution without controller intervention. Thus, decision aid tools are needed in Free Flight to detect and resolve conflicts, and several problems must be solved to develop such tools. In this report, we analyze and solve problems of proximity management, conflict detection, and conflict resolution under a Free Flight policy. For proximity management, we establish a system based on Delaunay Triangulations of aircraft at constant flight levels. Such a system provides a means for analyzing the neighbor relationships between aircraft and the nearby free space around air traffic which can be utilized later in conflict resolution. For conflict detection, we perform both 2-dimensional and 3-dimensional analyses based on the penetration of the Protected Airspace Zone. Both deterministic and non-deterministic analyses are performed. We investigate several types of conflict warnings including tactical warnings prior to penetrating the Protected Airspace Zone, methods based on the reachability overlap of both aircraft, and conflict probability maps to establish strategic Alert Zones around aircraft.

  7. Detecting conformational change by current transport in Bacteriorhodopsin

    Alfinito, Eleonora

    2008-01-01

    Charge transport modification exhibiting an increase of conductance activated by an external green light in Bacteriorhodopsin is correlated to its conformational change. A theoretical model based on a map of the protein structure into a resistor network is implemented to account for a sequential tunneling mechanism of charge transfer through neighbouring amino-acids. The model is validated by comparison with current-voltage experiments and provides for the potential barriers involved in the charge transfer an average height of 69 meV over an interacting radius of 6 \\aa. The predictability of the model is also tested on bovine rhodopsin, the prototype of the G protein coupled receptor (GPCR) family also sensitive to the light, with results exhibiting the opposite behaviour of a decrease of conductance in the presence of light.

  8. Allosteric Modulation of Muscarinic Acetylcholine Receptors

    Esam E. El-Fakahany

    2010-08-01

    Full Text Available An allosteric modulator is a ligand that binds to an allosteric site on the receptor and changes receptor conformation to produce increase (positive cooperativity or decrease (negative cooperativity in the binding or action of an orthosteric agonist (e.g., acetylcholine. Since the identification of gallamine as the first allosteric modulator of muscarinic receptors in 1976, this unique mode of receptor modulation has been intensively studied by many groups. This review summarizes over 30 years of research on the molecular mechanisms of allosteric interactions of drugs with the receptor and for new allosteric modulators of muscarinic receptors with potential therapeutic use. Identification of positive modulators of acetylcholine binding and function that enhance neurotransmission and the discovery of highly selective allosteric modulators are mile-stones on the way to novel therapeutic agents for the treatment of schizophrenia, Alzheimer’s disease and other disorders involving impaired cognitive function.

  9. The Role of Acetylcholine in Cocaine Addiction

    Williams, Mark J.; Adinoff, Bryon

    2007-01-01

    Central nervous system cholinergic neurons arise from several discrete sources, project to multiple brain regions, and exert specific effects on reward, learning, and memory. These processes are critical for the development and persistence of addictive disorders. Although other neurotransmitters, including dopamine, glutamate, and serotonin, have been the primary focus of drug research to date, a growing preclinical literature reveals a critical role of acetylcholine (ACh) in the experience a...

  10. Transportation Mode Detection Based on Permutation Entropy and Extreme Learning Machine

    Lei Zhang

    2015-01-01

    Full Text Available With the increasing prevalence of GPS devices and mobile phones, transportation mode detection based on GPS data has been a hot topic in GPS trajectory data analysis. Transportation modes such as walking, driving, bus, and taxi denote an important characteristic of the mobile user. Longitude, latitude, speed, acceleration, and direction are usually used as features in transportation mode detection. In this paper, first, we explore the possibility of using Permutation Entropy (PE of speed, a measure of complexity and uncertainty of GPS trajectory segment, as a feature for transportation mode detection. Second, we employ Extreme Learning Machine (ELM to distinguish GPS trajectory segments of different transportation. Finally, to evaluate the performance of the proposed method, we make experiments on GeoLife dataset. Experiments results show that we can get more than 50% accuracy when only using PE as a feature to characterize trajectory sequence. PE can indeed be effectively used to detect transportation mode from GPS trajectory. The proposed method has much better accuracy and faster running time than the methods based on the other features and SVM classifier.

  11. Performance Analysis of Transport Layer Basedhybrid Covert Channel Detection Engine

    Anjan K

    2013-11-01

    Full Text Available Computer network is unpredictable due to information warfareand is prone to various attacks. Such attackson network compromiseson the most important attribute, the privacy. Most of such attacksare devised usingspecial communication channel called Covert Channel".The word Covert" stands for hidden or non-transparent.Network Covert Channel is concealed communication paths within legitimatenetworkcommunication that clearly violates security policies laiddown. Non-transparency in covert channel isalsoreferred to as trapdoor.A trapdoor is unintended design within legitimate communication whosemotto isleak information. Subliminal channel, a variant ofcovert channelworks similarly as network covert channelexcept that trapdoor is setin cryptographic algorithm. A composition of covert channel withsubliminalchannel is the Hybrid Covert Channel". Hybrid covert channelis the homogeneous orheterogeneous mixture of two or more variantsof covert channel either active at same instance or atdifferent instanceof time. Detecting such maliciouschannel activity plays a vital role inremoving threat tolegitimate network.In this paper, we introduce newdetection engine for hybrid covert channelin transportlayer visualized in TCP and SSL. A setup made onexperimental test bed (DE-HCC9 in RD Lab of ourdepartment. Thepurpose of this study is to introduce few performance metrics to evaluatedetection engineand also to understand the multi-trapdoor natureofcovert channel.

  12. A Real-Time Pothole Detection Approach for Intelligent Transportation System

    Hsiu-Wen Wang

    2015-01-01

    Full Text Available In recent years, fast economic growth and rapid technology advance have led to significant impact on the quality of traditional transport system. Intelligent transportation system (ITS, which aims to improve the transport system, has become more and more popular. Furthermore, improving the safety of traffic is an important issue of ITS, and the pothole on the road causes serious harm to drivers’ safety. Therefore, drivers’ safety may be improved with the establishment of real-time pothole detection system for sharing the pothole information. Moreover, using the mobile device to detect potholes has been more popular in recent years. This approach can detect potholes with lower cost in a comprehensive environment. This study proposes a pothole detection method based on the mobile sensing. The accelerometer data is normalized by Euler angle computation and is adopted in the pothole detection algorithm to obtain the pothole information. Moreover, the spatial interpolation method is used to reduce the location errors from global positioning system (GPS data. In experiments, the results show that the proposed approach can precisely detect potholes without false-positives, and the higher accuracy is performed by the proposed approach. Therefore, the proposed real-time pothole detection approach can be used to improve the safety of traffic for ITS.

  13. A controlled field pilot for testing near surface CO2 detection techniques and transport models

    Spangler, L.H.; Dobeck, L.M.; Repasky, K.; Nehrir, A.; Humphries, S.; Keith, C.; Shaw, J.; Rouse, J.; Cunningham, A.; Benson, S.; Oldenburg, C.M.; Lewicki, J.L.; Wells, A.; Diehl, R.; Strazisar, B.; Fessenden, J.; Rahn, Thomas; Amonette, J.; Barr, J.; Pickles, W.; Jacobson, J.; Silver, E.; Male, E.; Rauch, H.; Gullickson, K.; Trautz, R.; Kharaka, Y.; Birkholzer, J.; Wielopolski, L.

    2009-01-01

    A field facility has been developed to allow controlled studies of near surface CO2 transport and detection technologies. The key component of the facility is a shallow, slotted horizontal well divided into six zones. The scale and fluxes were designed to address large scale CO2 storage projects and desired retention rates for those projects. A wide variety of detection techniques were deployed by collaborators from 6 national labs, 2 universities, EPRI, and the USGS. Additionally, modeling of CO2 transport and concentrations in the saturated soil and in the vadose zone was conducted. An overview of these results will be presented. ?? 2009 Elsevier Ltd. All rights reserved.

  14. A photonic crystal based sensing scheme for acetylcholine and acetylcholinesterase inhibitors

    Fenzl, Christoph; Genslein, Christa; Zöpfl, Alexander; Baeumner, Antje; Hirsch, Thomas

    2015-01-01

    We present a new scheme for sensing biomolecules by combining an enzyme hydrogel with a photonic crystal hydrogel layer that responds to ionic strength and pH changes. We demonstrate this unique combination by successfully detecting acetylcholine (ACh) and acetylcholinesterase (AChE) inhibitors. Specifically, the sandwich assembly is composed of layers of photonic crystals and a polyacrylamide hydrogel functionalized with AChE. The photonic crystal film has a red color and turns dark purple w...

  15. Bitter triggers acetylcholine release from polymodal urethral chemosensory cells and bladder reflexes

    Deckmann, Klaus; Filipski, Katharina; Krasteva-Christ, Gabriela; Fronius, Martin; Althaus, Mike; Rafiq, Amir; Papadakis, Tamara; Renno, Liane; Jurastow, Innokentij; Wessels, Lars; Wolff, Miriam; Schütz, Burkhard; Weihe, Eberhard; Chubanov, Vladimir; Gudermann, Thomas

    2014-01-01

    We report the presence of a previously unidentified cholinergic, polymodal chemosensory cell in the mammalian urethra, the potential portal of entry for bacteria and harmful substances into the urogenital system. These cells exhibit structural markers of respiratory chemosensory cells (“brush cells”). They use the classical taste transduction cascade to detect potential hazardous compounds (bitter, umami, uropathogenic bacteria) and release acetylcholine in response. They lie next to sensory ...

  16. Structural Studies of Nicotinic Acetylcholine Receptors: Using Acetylcholine Binding Protein as a Structural Surrogate

    Shahsavar, Azadeh; Gajhede, Michael; Kastrup, Jette; Balle, Thomas

    2015-01-01

    Nicotinic acetylcholine receptors (nAChRs) are members of the pentameric ligand-gated ion channel superfamily that play important roles in control of neurotransmitter release in the central and peripheral nervous system. These receptors are important therapeutic targets for development of drugs a...

  17. Facilitation of acetylcholine signaling by the dithiocarbamate fungicide propineb.

    Marinovich, Marina; Viviani, Barbara; Capra, Valerie; Corsini, Emanuela; Anselmi, Laura; D'Agostino, Gianluigi; Di Nucci, Amalia; Binaglia, Marco; Tonini, Marcello; Galli, Corrado L

    2002-01-01

    Dithiocarbamates (DTCs) are used mainly in agriculture as pesticides and as alcohol deterrent drugs. Neurological complications as well as movement disorders characterized by plastic rigidity, muscle twitch and paralysis are the prevailing symptoms in chronically exposed animals and humans. We investigated whether propineb interfered with peripheral cholinergic transmission in various isolated model systems. In electrically stimulated longitudinal muscle-myenteric plexus preparations (LMMPs), propineb (0.01-1000 nM) concentration-dependently enhanced the amplitude of both neurogenic twitch contractions and tritiated acetylcholine ([3H]ACh) release. The maximum percent increase was achieved by 10 nM propineb and was 19% and 14%, respectively. The effect on twitch contractions was partially antagonized by hexamethonium, a ganglionic nicotinic receptor blocker. In unstimulated LMMPs, propineb (10 pM, 10 nM, 10 microM) did not affect contractions to applied acetylcholine (ACh; 1 nM-10 microM), a finding indicating that propineb has no anticholinesterase activity. In human neuroblastoma cells (SH-SY5Y), propineb facilitated ACh release evoked by KCl depolarization. The increase in ACh release was not associated with detectable alterations of intracellular Ca2+([Ca2+]i) homeostasis. Binding studies carried out with alpha-bungarotoxin in striated muscle cells (L6) failed to demonstrate any influence of propineb on both affinity and capacity of skeletal muscle nicotinic receptors. In conclusion, propineb was found to interfere with cholinergic transmission in LMMPs and SH-SY5Y cells. In LMMPs, the potentiation of cholinergic transmission is partly dependent on the activation of ganglionic nicotinic receptors. Other targets relevant to cholinergic transmission seem not to be affected by propineb. PMID:11800594

  18. Expression and function of nicotinic acetylcholine receptors in stem cells

    Carlos M. Carballosa

    2016-07-01

    Full Text Available Nicotinic acetylcholine receptors are prototypical ligand gated ion channels typically found in muscular and neuronal tissues. Functional nicotinic acetylcholine receptors, however, have also recently been identified on other cell types, including stem cells. Activation of these receptors by the binding of agonists like choline, acetylcholine, or nicotine has been implicated in many cellular changes. In regards to stem cell function, nicotinic acetylcholine receptor activation leads to changes in stem cell proliferation, migration and differentiation potential. In this review we summarize the expression and function of known nicotinic acetylcholine receptors in different classes of stem cells including: pluripotent stem cells, mesenchymal stem cells, periodontal ligament derived stem cells, and neural progenitor cells and discuss the potential downstream effects of receptor activation on stem cell function.

  19. The effect of ketamine on intraspinal acetylcholine release

    Abelson, Klas S P; Goldkuhl, Renée Röstlinger; Nylund, Anders;

    2006-01-01

    The general anaesthetic ketamine affects the central cholinergic system in several manners, but its effect on spinal acetylcholine release, which may be an important transmitter in spinal antinociception, is unknown. This study aimed to investigate the effect of ketamine on spinal acetylcholine...... release. Microdialysis probes were placed intraspinally in male rats, and acetylcholine was quantified with HPLC. Anaesthesia was switched from isoflurane (1.3%) to ketamine (150 mg/kg h), which resulted in a 500% increased acetylcholine release. The increase was attenuated during nicotinic receptor...... blockade (50 microM mecamylamine). The nicotinic receptor agonist epibatidine (175 microM) produced a ten-fold higher relative increase of acetylcholine release during isoflurane anaesthesia compared to ketamine anaesthesia (270% to 27%). Intraspinal administration of ketamine and norketamine both...

  20. Acetylcholine determination of microdialysates of fetal neocortex grafts that induce recovery of learning.

    Miranda, M I; Bermúdez-Rattoni, F

    1998-03-01

    The microdialysis technique for acetylcholine (ACh) first became possible when sensitive and specific assays for ACh (pmol/sample range) were developed [G. Damsma, B.H.C. Westerink, P. de Boer, J.B. de Vries, A.S. Horn, Determination of basal acetylcholine release in freely moving rats by transstriatal dialysis coupled to on-line HPLC analysis: pharmacological aspects, Life Sci. 43 (1988) 1161-1168; G. Damsma, B.H.C. Westerink, A. Imperato, H. Rollema, J.B. de Vries, A. S. Horn, Automated brain dialysis of acetylcholine in freely moving rats: detection of basal acetylcholine, Life Sci. 41 (1987) 873-876; P.E. Potter, J.L. Meek, N.H. Neff, Acetylcholine and choline in neural tissue measured by HPLC with electrochemical detection, J. Neurochem. 41 (1983) 188-194; B.H.C. Westerink, G. Damsma, Determination of acetylcholine in microdialysates by HPLC and electrochemical detection, Neurosci. Protocols 20 (1993) 1-9.]. In the present protocol, the microdialysis technique was used to correlate ACh release with the recovery of the ability to acquire a conditioning taste aversion (CTA), by fetal brain grafts in insular cortex (IC) lesioned rats [M.I. Miranda, A.M. Lopez-Colome, F. Bermúdez Rattoni, Recovery of conditional taste aversion induced by fetal neocortex grafts. In vivo correlation of acetylcholine levels, Brain Res. 759 (1997) 141-148]. Three groups of IC lesioned rats showing disrupted CTA received cell suspension grafts of fetal tissue dissected from either the IC or occipital cortex (OC) of 16-day-old rat fetuses. One of the groups of IC-grafted animals was tested after 15 days post-graft; the other groups, IC- and OC-grafted animals, were tested after a recovery time of 45 days, as well as the groups of lesioned and unoperated animals used as control. After the CTA test, guide cannulas were stereotaxically implanted into the IC of all groups. Two days later, microdialysis was performed to determine the extracellular levels of ACh inside the graft. The

  1. Performance of Four Transport and Storage Systems for Molecular Detection of Multidrug-Resistant Tuberculosis

    Rabodoarivelo, Marie Sylvianne; Imperiale, Bélen; andrianiavomikotroka, Rina; Brandao, Angela; Kumar, Parveen; Singh, Sarman; Ferrazoli, Lucilaine; Morcillo, Nora; Rasolofo, Voahangy; Palomino, Juan Carlos; Vandamme, Peter; Martin, Anandi

    2015-01-01

    Background Detection of drug-resistant tuberculosis is essential for the control of the disease but it is often hampered by the limitation of transport and storage of samples from remote locations to the reference laboratory. We performed a retrospective field study to evaluate the performance of four supports enabling the transport and storage of samples to be used for molecular detection of drug resistance using the GenoType MTBDRplus. Methods Two hundred Mycobacterium tuberculosis strains were selected and spotted on slides, FTA cards, GenoCards, and in ethanol. GenoType MTBDRplus was subsequently performed with the DNA extracted from these supports. Sensitivity and specificity were calculated and compared to the results obtained by drug susceptibility testing. Results For all supports, the overall sensitivity and specificity for detection of resistance to RIF was between 95% and 100%, and for INH between 95% and 98%. Conclusion The four transport and storage supports showed a good sensitivity and specificity for the detection of resistance to RIF and INH in M. tuberculosis strains using the GenoType MTBDRplus. These supports can be maintained at room temperature and could represent an important alternative cost-effective method useful for rapid molecular detection of drug-resistant TB in low-resource settings. PMID:26431352

  2. The Detection of Transport Land-Use Data Using Crowdsourcing Taxi Trajectory

    Ai, T.; Yang, W.

    2016-06-01

    This study tries to explore the question of transport land-use change detection by large volume of vehicle trajectory data, presenting a method based on Deluanay triangulation. The whole method includes three steps. The first one is to pre-process the vehicle trajectory data including the point anomaly removing and the conversion of trajectory point to track line. Secondly, construct Deluanay triangulation within the vehicle trajectory line to detect neighborhood relation. Considering the case that some of the trajectory segments are too long, we use a interpolation measure to add more points for the improved triangulation. Thirdly, extract the transport road by cutting short triangle edge and organizing the polygon topology. We have conducted the experiment of transport land-use change discovery using the data of taxi track in Beijing City. We extract not only the transport land-use area but also the semantic information such as the transformation speed, the traffic jam distribution, the main vehicle movement direction and others. Compared with the existed transport network data, such as OpenStreet Map, our method is proved to be quick and accurate.

  3. Chemical stimulation of adherent cells by localized application of acetylcholine from a microfluidic system.

    Zibek, Susanne; Hagmeyer, Britta; Stett, Alfred; Stelzle, Martin

    2010-01-01

    Chemical stimulation of cells is inherently cell type selective in contrast to electro-stimulation. The availability of a system for localized application of minute amounts of chemical stimulants could be useful for dose related response studies to test new compounds. It could also bring forward the development of a novel type of neuroprostheses. In an experimental setup microdroplets of an acetylcholine solution were ejected from a fluidic microsystem and applied to the bottom of a nanoporous membrane. The solution traveled through the pores to the top of the membrane on which TE671 cells were cultivated. Calcium imaging was used to visualize cellular response with temporal and spatial resolution. Experimental demonstration of chemical stimulation for both threshold gated stimulation as well as accumulated dose-response was achieved by either employing acetylcholine as chemical stimulant or applying calcein uptake, respectively. Numerical modeling and simulation of transport mechanisms involved were employed to gain a theoretical understanding of the influence of pore size, concentration of stimulant and droplet volume on the spatial-temporal distribution of stimulant and on the cellular response. Diffusion, pressure driven flow and evaporation effects were taken into account. Fast stimulation kinetic is achieved with pores of 0.82 μm diameter, whereas sustained substance delivery is obtained with nanoporous membranes. In all cases threshold concentrations ranging from 0.01 to 0.015 μM acetylcholine independent of pore size were determined. PMID:21151808

  4. Chemical Stimulation of Adherent Cells by Localized Application of Acetylcholine from a Microfluidic System

    Zibek, Susanne; Hagmeyer, Britta; Stett, Alfred; Stelzle, Martin

    2010-01-01

    Chemical stimulation of cells is inherently cell type selective in contrast to electro-stimulation. The availability of a system for localized application of minute amounts of chemical stimulants could be useful for dose related response studies to test new compounds. It could also bring forward the development of a novel type of neuroprostheses. In an experimental setup microdroplets of an acetylcholine solution were ejected from a fluidic microsystem and applied to the bottom of a nanoporous membrane. The solution traveled through the pores to the top of the membrane on which TE671 cells were cultivated. Calcium imaging was used to visualize cellular response with temporal and spatial resolution. Experimental demonstration of chemical stimulation for both threshold gated stimulation as well as accumulated dose–response was achieved by either employing acetylcholine as chemical stimulant or applying calcein uptake, respectively. Numerical modeling and simulation of transport mechanisms involved were employed to gain a theoretical understanding of the influence of pore size, concentration of stimulant and droplet volume on the spatial-temporal distribution of stimulant and on the cellular response. Diffusion, pressure driven flow and evaporation effects were taken into account. Fast stimulation kinetic is achieved with pores of 0.82 μm diameter, whereas sustained substance delivery is obtained with nanoporous membranes. In all cases threshold concentrations ranging from 0.01 to 0.015 μM acetylcholine independent of pore size were determined. PMID:21151808

  5. Structural model of nicotinic acetylcholine receptor isotypes bound to acetylcholine and nicotine

    Abagyan Ruben

    2002-01-01

    Full Text Available Abstract Background Nicotine is a psychoactive drug presenting a diverse array of biological activities, some positive, such as enhancement of cognitive performances, others negative, such as addiction liability. Ligands that discriminate between the different isotypes of nicotinic acetylcholine receptors (nAChRs could present improved pharmacology and toxicity profile. Results Based on the recent crystal structure of a soluble acetylcholine binding protein from snails, we have built atomic models of acetylcholine and nicotine bound to the pocket of four different human nAChR subtypes. The structures of the docked ligands correlate with available biochemical data, and reveal that the determinants for isotype selectivity are relying essentially on four residues, providing diversity of the ligand binding pocket both in terms of Van der Waals boundary, and electrostatic potential. We used our models to screen in silico a large compound database and identify a new ligand candidate that could display subtype selectivity. Conclusion The nAChR-agonist models should be useful for the design of nAChR agonists with diverse specificity profiles.

  6. Spin transport, magnetoresistance, and electrically detected magnetic resonance in amorphous hydrogenated silicon nitride

    Mutch, Michael J.; Lenahan, Patrick M.; King, Sean W.

    2016-08-01

    We report on a study of spin transport via electrically detected magnetic resonance (EDMR) and near-zero field magnetoresistance (MR) in silicon nitride films. Silicon nitrides have long been important materials in solid state electronics. Although electronic transport in these materials is not well understood, electron paramagnetic resonance studies have identified a single dominating paramagnetic defect and have also provided physical and chemical descriptions of the defects, called K centers. Our EDMR and MR measurements clearly link the near-zero field MR response to the K centers and also indicate that K center energy levels are approximately 3.1 eV above the a-SiN:H valence band edge. In addition, our results suggest an approach for the study of defect mediated spin-transport in inorganic amorphous insulators via variable electric field and variable frequency EDMR and MR which may be widely applicable.

  7. Equipment of high sensitivity to detect smuggled radioactive materials transported across the ''east-west'' border

    An equipment specially developed for the customs radiation control is described. Its sensitivity is higher than requirements of western countries. The equipment ensures an alarm when a radioactive source (both shielded or not) is found in the controlled area, localizes and identifies the source detected, and provides the radiation protection of customs personnel. Most of devices have a non-volatile memory where the radiation situation history is stored and then transferred to PC. The equipment may be used by personnel of special services for secret detection of radioactive materials. Some Belarussian and Russian documents specifying measures to prevent an unauthorized transportation of radioactive materials are discussed. (author)

  8. The α7 nicotinic acetylcholine receptor complex

    Thomsen, Morten Skøtt; Mikkelsen, Jens D

    2012-01-01

    The α7 nicotinic acetylcholine receptor (nAChR) is a promising drug target for a number of diseases ranging from schizophrenia and Alzheimer's disease to chronic pain and inflammatory diseases. Focusing on the central nervous system, we describe how endogenous and experimental compounds and...... compounds in vivo is highly dependent on α7 nAChR-interacting proteins, such as RIC-3 and lynx1, which modulate expression and function of the receptor. These regulatory proteins are often not expressed in in vitro models used to study α7 nAChR function, and it is not known to what extent they are involved...... in diseases such as schizophrenia and Alzheimer's disease. Furthermore, α7 nAChR agonists and allosteric modulators differentially alter expression and functionality of the α7 nAChR with repeated administration, which suggests that there may be fundamentally different outcomes of long...

  9. Inhibition of acetylcholine synthesis in vitro

    In order to better understand diseases that stem from deficiencies in cholinergic activity, reproducible in vitro and in vivo models displaying cholinergic hypofunction are desirable. This necessitates the availability of specific inhibitors. This paper examines the design, synthesis and evaluation of quinuclidinyl compounds with structural features previously reported, but with certain key differences. Structure activity studies with in vitro assay systems are presented. In a few studies, choline was held constant and acetyl-CoA concentration was varied, but with a constant amount of (14C) - acetyl CoA. Acetylcholine synthesis and CO2 production from labelled glucose were measured in cerebral cortex slices from male rats after decapitation. The nanomoles of ACh and CO2 produced from (14C) -glucose were calculated from glucose specific activity. Results are presented

  10. Cocaine Inhibition of Nicotinic Acetylcholine ReceptorsInfluences Dopamine Release

    Alexandra eAcevedo-Rodriguez

    2014-09-01

    Full Text Available Nicotinic acetylcholine receptors (nAChRs potently regulate dopamine (DA release in the striatum and alter cocaine’s ability to reinforce behaviors. Since cocaine is a weak nAChR inhibitor, we hypothesized that cocaine may alter DA release by inhibiting the nAChRs in DA terminals in the striatum and thus contribute to cocaine's reinforcing properties primarily associated with the inhibition of DA transporters. We found that biologically relevant concentrations of cocaine can mildly inhibit nAChR-mediated currents in midbrain DA neurons and consequently alter DA release in the dorsal and ventral striatum. At very high concentrations, cocaine also inhibits voltage-gated Na channels in DA neurons. Furthermore, our results show that partial inhibition of nAChRs by cocaine reduces evoked DA release. This diminution of DA release via nAChR inhibition more strongly influences release evoked at low or tonic stimulation frequencies than at higher (phasic stimulation frequencies, particularly in the dorsolateral striatum. This cocaine-induced shift favoring phasic DA release may contribute to the enhanced saliency and motivational value of cocaine-associated memories and behaviors.

  11. Role of acetylcholine on plant root-shoot signal transduction

    2003-01-01

    The role of acetylcholine (ACh) on plant root- shoot communication was investigated using the root-split system of Vicia faba L. In the experiments, slight osmotic stress caused the decrease of ACh content in root tips and the xylem sap transported up per time unit from root tip to the shoot when the water potential of the shoot was kept unchanged. It also caused the decrease of ACh content in the abaxial epidermis. The decrease was highly correlative to the changes of transpiration rate, suggesting that the decrease of ACh content probably functions as a signal to regulate stomatal behavior. The effect of osmotic stress might be mainly through the inhibition of the ACh synthesis in root tip; thus further influences the ACh content in root tip, xylem sap and abaxial epidermis and resulting in the changes of stomatal behavior. These results provide new evidence that plants transduce positive and negative signals among roots and shoots to coordinate stomatal behavior and adapt to variable environments.

  12. Acoustic wave detection of chemical species electrokinetically transported within a capillary tube.

    Li, Paul C H; Prasad, Ronald

    2003-06-01

    For the first time, we report the acoustic wave detection of chemical species being transported in a capillary tube to a region where acoustic coupling occurs. The measured parameter was a change in phase, which was originally only attributed to a change in solution density as the analyte passed by the detection region. Accordingly, we report the detection of change in phase as various chemical species (e.g. Cy5 dye, Cy5-derivatized glycine and underivatized glycine) were introduced into and migrated along a capillary tube through electrokinetic processes. To improve detection sensitivity, we modified various experimental parameters, such as run buffer concentration, capillary wall thickness and transducer frequency. Although acoustic wave detection was feasible, the peak width and detection limit were inadequate as compared to conventional detection methods for HPLC or CE. Nevertheless, the effects of various physical and chemical relaxation processes on acoustic wave absorption were discussed, and this has shed some light on explaining some observations, which cannot be explained by density differences alone. Accordingly, the acoustic wave method is suggested to investigate these processes, as studied in ultrasonic relaxation spectroscopy, in a flow system. PMID:12866892

  13. Detection and characterization of uranium-humic complexes during 1D transport studies

    Lesher, Emily K. [Colorado School of Mines, Golden, CO (United States). Civil and Environmental Engineering; Honeyman, Bruce D. [Colorado School of Mines, Golden, CO (United States). Civil and Environmental Engineering; Ranville, James F. [Colorado School of Mines, Golden, CO (United States). Dept. of Chemistry and Geochemistry

    2013-05-01

    The speciation and transport of uranium (VI) through porous media is highly dependent on solution conditions, the presence of complexing ligands, and the nature of the porous media. The dependency on many variables makes prediction of U transport in bench-scale experiments and in the field difficult. In particular, the identification of colloidal U phases poses a technical challenge. Transport of U in the presence and absence of natural organic matter (Suwannee River humic acid, SRHA) through silica sand and hematite coated silica sand was tested at pH 4 and 5 using static columns, where flow is controlled by gravity and residence time between advective pore volume exchanges can be strictly controlled. The column effluents were characterized by traditional techniques including ICPMS quantification of total [U] and [Fe], TOC analysis of [DOC], and pH analysis, and also by non-traditional techniques: flow field flow fractionation with online ICPMS detection (FlFFF-ICPMS) and specific UV absorbance (SUVA) characterization of effluent fractions. Key results include that the transport of U through the columns was enhanced by pre-equilibration with SRHA, and previously deposited U was remobilized by the addition of SRHA. The advanced techniques yielded important insights on the mechanisms of transport: FlFFF-ICPMS identified a U-SRHA complex as the mobile U species and directly quantified relative amounts of the complex, while specific UV absorbance (SUVA) measurements indicated a composition-based fractionation onto the porous media.

  14. Chemical stimulation of adherent cells by localized application of acetylcholine from a microfluidic system

    Susanne Zibek

    2010-11-01

    Numerical modelling and simulation of transport mechanisms involved were employed to gain a theoretical understanding of the influence of pore size, concentration of stimulant and droplet volume on the spatial-temporal distribution of stimulant and on the cellular response. Diffusion, pressure driven flow and evaporation effects were taken into account. Fast stimulation kinetic is achieved with pores of 0.82 µm diameter, whereas sustained substance delivery is obtained with nanoporous membranes. In all cases threshold concentrations ranging from 0.01 to 0.015 µM acetylcholine independent of pore size were determined.

  15. Hybrid light transport model based bioluminescence tomography reconstruction for early gastric cancer detection

    Chen, Xueli; Liang, Jimin; Hu, Hao; Qu, Xiaochao; Yang, Defu; Chen, Duofang; Zhu, Shouping; Tian, Jie

    2012-03-01

    Gastric cancer is the second cause of cancer-related death in the world, and it remains difficult to cure because it has been in late-stage once that is found. Early gastric cancer detection becomes an effective approach to decrease the gastric cancer mortality. Bioluminescence tomography (BLT) has been applied to detect early liver cancer and prostate cancer metastasis. However, the gastric cancer commonly originates from the gastric mucosa and grows outwards. The bioluminescent light will pass through a non-scattering region constructed by gastric pouch when it transports in tissues. Thus, the current BLT reconstruction algorithms based on the approximation model of radiative transfer equation are not optimal to handle this problem. To address the gastric cancer specific problem, this paper presents a novel reconstruction algorithm that uses a hybrid light transport model to describe the bioluminescent light propagation in tissues. The radiosity theory integrated with the diffusion equation to form the hybrid light transport model is utilized to describe light propagation in the non-scattering region. After the finite element discretization, the hybrid light transport model is converted into a minimization problem which fuses an l1 norm based regularization term to reveal the sparsity of bioluminescent source distribution. The performance of the reconstruction algorithm is first demonstrated with a digital mouse based simulation with the reconstruction error less than 1mm. An in situ gastric cancer-bearing nude mouse based experiment is then conducted. The primary result reveals the ability of the novel BLT reconstruction algorithm in early gastric cancer detection.

  16. Methodologic aspects of acetylcholine-evoked relaxation of rabbit aorta.

    Hansen, K; Nedergaard, O A

    1999-08-01

    The acetylcholine-evoked relaxation of rabbit isolated thoracic aorta precontracted by phenylephrine was studied. Phenylephrine caused a steady contraction that was maintained for 6 h. In the presence of calcium disodium ethylenediaminetetraacetate (EDTA) and ascorbic acid the contraction decreased with time. N(G)-Nitro-L-arginine abolished the inhibitory effect of EDTA and ascorbic acid. Acetylcholine evoked a rapid concentration-dependent relaxation that recovered spontaneously and slowly, but fully, with time. Relaxation evoked by equieffective concentrations of carbachol and acetylcholine had the same time course. Cumulative addition of acetylcholine (10(-7)-3 x 10(-5) M) caused a marked relaxation that was reverted slightly at high concentrations. The relaxation was the same with rings derived from the upper, middle, and lower part of the thoracic aorta. Two consecutive concentration-response curves for acetylcholine obtained at a 2-h interval demonstrated a slight development of tachyphylaxis. The relaxation was inversely related to precontractile tension evoked by phenylephrine when expressed as a percentage, but independent when expressed as g tension. Storage of aorta in cold salt solution for 24 h did not alter the relaxation. EDTA and ascorbic acid did not alter the relaxation. It is concluded that (1) EDTA and ascorbic acid can not be used with impunity to stabilize catecholamines used as preconstriction agents; (2) the reversal of the acetylcholine-evoked relaxation is not due to hydrolysis of acetylcholine; (3) the relaxation is uniform in all segments of thoracic aorta; (4) cold storage of aorta does not alter the relaxation; and (5) acetylcholine releases the same amount of relaxing factor, irrespective of the precontractile tension. PMID:10691020

  17. Passive mass transport for direct and quantitative SERS detection using purified silica encapsulated metal nanoparticles

    Shrestha, Binaya Kumar

    This thesis focuses on understanding implications of nanomaterial quality control and mass transport through internally etched silica coated nanoparticles for direct and quantitative molecular detection using surface enhanced Raman scattering (SERS). Prior to use, bare nanoparticles (partially or uncoated with silica) are removal using column chromatography to improve the quality of these nanomaterials and their SERS reproducibility. Separation of silica coated nanoparticles with two different diameters is achieved using Surfactant-free size exclusion chromatography with modest fractionation. Next, selective molecular transport is modeled and monitored using SERS and evaluated as a function of solution ionic strength, pH, and polarity. Molecular detection is achieved when the analytes first partition through the silica membrane then interact with the metal surface at short distances (i.e., less than 2 nm). The SERS intensities of unique molecular vibrational modes for a given molecule increases as the number of molecules that bind to the metal surface increases and are enhanced via both chemical and electromagnetic enhancement mechanisms as long as the vibrational mode has a component of polarizability tensor along the surface normal. SERS signals increase linearly with molecular concentration until the three-dimensional SERS-active volume is saturated with molecules. Implications of molecular orientation as well as surface selection rules on SERS intensities of molecular vibrational modes are studied to improve quantitative and reproducible SERS detection using internally etched Ag Au SiO2 nanoparticles. Using the unique vibrational modes, SERS intensities for p-aminothiophenol as a function of metal core compositions and plasmonics are studied. By understanding molecular transport mechanisms through internally etched silica matrices coated on metal nanoparticles, important experimental and materials design parameters are learned, which can be subsequently applied

  18. Crucial technologies of oil-transporting pipe leak detection and location based on wavelet and chaos

    Zhang, S. Q.; Jin, S. J.; Yang, F. L.; Wang, X. Q.; Bai, Q. Y.

    2006-03-01

    By detecting pressure and flux simultaneously, the leak of an oil-transporting pipe can be found and diagnosed synthetically. The flux of pipes is measured by an ultrasonic flow meter; considering the precision of the flux measured, a method based on the character of intermittent chaos of the Duffing system to detect weak signals under strong noise is introduced. The ultrasonic signals with a certain frequency could be extracted accurately from the complicated strong noise. So the flux of pipes can be computed precisely by an accurate ultrasonic signal. The location of a leak position is mainly determined by the time difference between the negative pressure waves measured by the pressure sensors located at both ends of the oil-transporting pipe. A singular point of a negative pressure wave can be judged accurately by a coefficient feature of the local extreme values of the wavelet transform. So, the precise location of the leak position of the oil-transporting pipe can be found. It can be shown by results of experiments that the precision of the leak location has been improved effectively, which can be about 1%.

  19. Identification of petrogenic produced water components as acetylcholine esterase inhibitors.

    Froment, Jean; Langford, Katherine; Tollefsen, Knut Erik; Bråte, Inger Lise N; Brooks, Steven J; Thomas, Kevin V

    2016-08-01

    Effect-directed analysis (EDA) was applied to identify acetylcholine esterase (AChE) inhibitors in produced water. Common produced water components from oil production activities, such as polycyclic aromatic hydrocarbons (PAHs), alkylphenols, and naphthenic acids were tested for AChE inhibition using a simple mixture of PAHs and naphthenic acids. Produced water samples collected from two offshore platforms in the Norwegian sector of the North Sea were extracted by solid phase extraction and fractionated by open-column liquid solid chromatography and high-performance liquid chromatography (HPLC) before being tested using a high-throughput and automated AChE assay. The HPLC fractions causing the strongest AChE inhibition were analysed by gas chromatography coupled to a high-resolution time-of-flight mass spectrometry (GC-HR-ToF-MS). Butylated hydroxytoluene and 4-phenyl-1,2-dihydronaphthalene were identified as two produced water components capable of inhibiting AChE at low concentrations. In order to assess the potential presence of such compounds discharged into aquatic ecosystems, AChE activity in fish tissues was measured. Saithe (Pollachius virens) caught near two offshore platforms showed lower enzymatic activity than those collected from a reference location. Target analysis of saithe did not detected the presence of these two putative AChE inhibitors and suggest that additional compounds such as PAHs, naphthenic acids and yet un-identified compounds may also contribute to the purported AChE inhibition observed in saithe. PMID:27176761

  20. Influence of atmospheric transport patterns on xenon detections at the CTBTO radionuclide network

    Krysta, Monika; Kusmierczyk-Michulec, Jolanta

    2016-04-01

    In order to fulfil its task of monitoring for signals emanating from nuclear explosions, Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) operates global International Monitoring System (IMS) comprising seismic, infrasound, hydroacoustic and radionuclide measurement networks. At present, 24 among 80 radionuclide stations foreseen by the Comprehensive Nuclear-Test-Ban Treaty (CTBT) are equipped with certified noble gas measurement systems. Over a past couple of years these systems collected a rich set of measurements of radioactive isotopes of xenon. Atmospheric transport modelling simulations are crucial to an assessment of the origin of xenon detected at the IMS stations. Numerous studies undertaken in the past enabled linking these detections to non Treaty-relevant activities and identifying main contributors. Presence and quantity of xenon isotopes at the stations is hence a result of an interplay of emission patterns and atmospheric circulation. In this presentation we analyse the presence or absence of radioactive xenon at selected stations from an angle of such an interplay. We attempt to classify the stations according to similarity of detection patterns, examine seasonality in those patterns and link them to large scale or local meteorological phenomena. The studies are undertaken using crude hypotheses on emission patterns from known sources and atmospheric transport modelling simulations prepared with the FLEXPART model.

  1. The ATR noninvasive detection of transported medicinal ions and the performance of newly designed iontophoresis instruments

    Ueda, Toyotoshi; Watanabe, Yukio; Suzuki, Harue

    2005-02-01

    The attenuated total reflection and near-infrared diffusive-reflection methods are proposed as safe and powerful ways to detect and measure the quantity of medication transported by iontophoresis. Especially, the former method can evaluate the quantity of such negative ions as L-ascorbyl-2-phosphate in the top (horny) layer of epidermis (about 1 μm under the skin surface) using, respectively, characteristic ion's bands. Factors making iontophoresis more effective are discussed from the points of electric currents, duty ratio, frequency of superposing intermittent current, simultaneous supersonic perforation, etc. The use of intermittent direct current superposed by 40 kHz pulsed current and pulse irradiation of supersonic waves accelerated drastically the disappearing rate of transported ions from the horny layer with a life of 10 h to 1 min. This technique may be applied to a new and powerful drug delivery system into topical deep tissues.

  2. A transportable fast neutron and dual gamma-ray system for the detection of illicit materials

    A transportable FNGR radiography system has been simulated using the MCNPX Monte Carlo code. The system is envisaged to be applied to the material characterisation of a suspicious bulky object, in view of identifying illegal materials. The system combines a neutron and two gamma-ray sources achieving characterisation of the material of the object through two ratios, namely 137Cs/DD and 60Co/DD. Hence, the system discriminates materials of similar or even the same of either of the two ratios. The proposed unit complies with radiation protection requirements achieving a safe occupational environment. - Highlights: → Transportable radiography system. → Neutron- and dual energy photon-beams available. → Discrimination of materials. → Detection of illicit materials.

  3. A transportable fast neutron and dual gamma-ray system for the detection of illicit materials

    Fantidis, J.G. [Laboratory of Nuclear Technology, School of Engineering, ' Democritus' University of Thrace, Vas. Sofias 12, Xanthi 67100 (Greece); Nicolaou, G.E., E-mail: nicolaou@ee.duth.gr [Laboratory of Nuclear Technology, School of Engineering, ' Democritus' University of Thrace, Vas. Sofias 12, Xanthi 67100 (Greece)

    2011-08-21

    A transportable FNGR radiography system has been simulated using the MCNPX Monte Carlo code. The system is envisaged to be applied to the material characterisation of a suspicious bulky object, in view of identifying illegal materials. The system combines a neutron and two gamma-ray sources achieving characterisation of the material of the object through two ratios, namely {sup 137}Cs/DD and {sup 60}Co/DD. Hence, the system discriminates materials of similar or even the same of either of the two ratios. The proposed unit complies with radiation protection requirements achieving a safe occupational environment. - Highlights: > Transportable radiography system. > Neutron- and dual energy photon-beams available. > Discrimination of materials. > Detection of illicit materials.

  4. Supporting data for 'Vortex detection and quantum transport in mesoscopic graphene Josephson-junction arrays'

    Richardson, C. L.; Edkins, S. D.; Berdiyorov, G. R.; Chua, C. J.; Griffiths, J. P.; Jones, G. A. C.; Buitelaar, M.R.; Narayan, V; Sfigakis, F.; Smith, C. G.; Covaci, L.; Connolly, M. R.

    2015-01-01

    The files listed below are raw experimental data from 'Vortex detection and quantum transport in mesoscopic graphene Josephson-junction arrays' by C. L. Richardson et al., to appear in Phys. Rev. B. The three-part files (filename, filenameHdr and filenameSD) are in tab-separated .txt format, produced by CryoMeas (written by C. J. B. Ford). Only a subset of the Fig. 6 dataset is included. 20130514-040 (device A, Fig. 2(a) and 3) 20130515-041 (device A, Fig. 2(a) and 3) 20130809-066 (...

  5. New Sensor Cable for the Detection and Location of Leaks in Pipelines for Transportation of Hydrocarbons

    E.Orduña-Reyes

    2012-08-01

    Full Text Available At present, hydrocarbon leaks, generated mainly by corrosion of pipelines, cause large economic losses for Mexico.These leaks constitute a problem of serious consequences in Mexico and in other countries in the world. This workdescribes the results of the tests conducted on a new sensor cable for the detection and location of leaks in pipelinesfor transportation of hydrocarbons. When a liquid or gas enters in contact with the wall of the sensor cable, it causes ashort circuit in the wires; changing the measurement of the resistance may detect and locate the leak. The new sensorcable that is presented in this article has advantages over cables with similar characteristic made in other countries.The use of this sensor cable in pipelines of PEMEX will avoid economic losses, environmental damage and risks ofpossible explosions to the population. The experimental results demonstrate these advantages.

  6. Structural Studies of Nicotinic Acetylcholine Receptors: Using Acetylcholine-Binding Protein as a Structural Surrogate.

    Shahsavar, Azadeh; Gajhede, Michael; Kastrup, Jette S; Balle, Thomas

    2016-06-01

    Nicotinic acetylcholine receptors (nAChRs) are members of the pentameric ligand-gated ion channel superfamily that play important roles in the control of neurotransmitter release in the central and peripheral nervous system. These receptors are important therapeutic targets for the development of drugs against a number of mental health disorders and for marketed smoking cessation aids. Unfortunately, drug discovery has been hampered by difficulties in obtaining sufficiently selective compounds. Together with functional complexity of the receptors, this has made it difficult to obtain drugs with sufficiently high-target to off-target affinity ratios. The recent and ongoing progress in structural studies holds promise to help understand structure-function relationships of nAChR drugs at the atomic level. This will undoubtedly lead to the design of more efficient drugs with fewer side effects. As a high-resolution structure of a nAChR is yet to be determined, structural studies are to a large extent based on acetylcholine-binding proteins (AChBPs) that despite low overall sequence identity display a high degree of conservation of overall structure and amino acids at the ligand-binding site. Further, AChBPs reproduce relative binding affinities of ligands at nAChRs. Over the past decade, AChBPs have been used extensively as models for nAChRs and have aided the understanding of drug receptor interactions at nAChRs significantly. PMID:26572235

  7. Interaction of ibogaine with human α3β4-nicotinic acetylcholine receptors in different conformational states

    Arias, Hugo R.; Rosenberg, Avraham; Targowska-Duda, Katarzyna M.; Feuerbach, Dominik; Yuan, Xiao Juan; Jozwiak, Krzysztof; Moaddel, Ruin; Wainer, Irving W.

    2010-01-01

    The interaction of ibogaine and phencyclidine (PCP) with human (h) α3β4-nicotinic acetylcholine receptors (AChRs) in different conformational states was determined by functional and structural approaches including, radioligand binding assays, Ca2+ influx detections, and thermodynamic and kinetics measurements. The results established that (a) ibogaine inhibits (±)-epibatidine-induced Ca2+ influx in hα3β4 AChRs with ~9-fold higher potency than that for PCP, (b) [3H]ibogaine binds to a single s...

  8. m1 Acetylcholine Receptor Expression is Decreased in Hippocampal CA1 region of Aged Epileptic Animals

    Cavarsan, Clarissa Fantin; Avanzi, Renata Della Torre; Queiroz, Claudio Marcos; Xavier, Gilberto Fernando; Mello, Luiz Eugênio; Covolan, Luciene

    2011-01-01

    In the present study, we investigated the possible additive effects of epilepsy and aging on the expression of m1 muscarinic acetylcholine receptors (AChR) in the rat hippocampus. Young (3 months) and Aged (20 months) male, Wistar rats were treated with pilocarpine to induce status epilepticus (SE). Immunohistochemical procedure for m1 AChR detection was performed 2 months after pilocarpine-induced SE. In the CA1 pyramidal region m1 AChR staining was significantly decreased in aged epileptic ...

  9. Simulation of atmospheric krypton-85 transport to assess the detectability of clandestine nuclear reprocessing

    Ross, Jens Ole

    2010-02-02

    The radioactive noble gas krypton-85 is released into the atmosphere during reprocessing of spent nuclear fuel or irradiated breeding targets. This is a necessary step for plutonium separation. Therefore the {sup 85}Kr signature of reprocessing could possibly be used for the detection of undeclared nuclear facilities producing nuclear weaponusable material. The {sup 85}Kr content of the atmosphere has grown over the last decades as the emissions from military and civilian nuclear industry could not be compensated by the decay with a half-life of 10.76 years. In this study, the global {sup 85}Kr background distribution due to emissions of known reprocessing facilities for the period from 1971 until 2006 was simulated using the atmospheric general circulation model ECHAM5 applying the newest available annual emission data. The convective tracer transport scheme and the operator splitting for the physical calculations in the model were modified in order to guarantee physically correct results for tracer point sources, in particular non negative concentrations. An on-line routine controlling the {sup 85}Kr -budget in the model enforced exact mass conservation. The results of the simulation were evaluated by extensive comparison with measurements performed by the German Federal Office for Radiation Protection with very good agreement at most observation sites except those in the direct vicinity of {sup 85}Kr sources. Of particular interest for the {sup 85}Kr detection potential was the variability of {sup 85}Kr background concentrations which was evaluated for the first time in a global model. In addition, the interhemispheric transport as simulated by ECHAM5 was analyzed using a two-box model providing a mean exchange time of τ {sub ex} = 10.5 months. The analysis of τ{sub ex} over simulated 35 years indicates that in years with strong South Asian or African Monsoon the interhemispheric transport is faster during the monsoon season. A correlation analysis of

  10. Defect chemistry and electronic transport in low-κ dielectrics studied with electrically detected magnetic resonance

    Mutch, Michael J.; Lenahan, Patrick M.; King, Sean W.

    2016-03-01

    Defect mediated electronic transport phenomena in low-κ dielectric films are of great technological interest for state-of-the-art and next generation microprocessors. At the present time, the leading low-κ interlayer dielectrics and etch-stop layers are based upon a-SiOC:H and a-SiCN:H, respectively. In this study, we utilize electrically detected magnetic resonance (EDMR), a derivative of electron paramagnetic resonance, to provide physical insight into electronic transport, as well as the nature and origin of defects in dense and porous a-SiOC:H and dense a-SiCN:H films. Resonance measurements are performed before and after the removal of sacrificial porogens via UV treatments to understand the role of specific defect centers in electronic transport in a-SiOC:H systems, and the nature of defects created by UV treatments. Unfortunately, a-SiOC:H and a-SiCN:H EDMR spectra are relatively broad and featureless. These featureless spectra are consistent with fairly complex a-SiOC:H and a-SiCN:H systems. We argue that physical insight may be gleaned from featureless spectra via multiple frequency EDMR. Baseline multiple frequency EDMR measurements are performed in a-Si:H and a-C:H to illustrate the nature of line broadening mechanisms of silicon and carbon related defects.

  11. α4 nicotinic acetylcholine receptor modulated by galantamine on nigrostriatal terminals regulates dopamine receptor-mediated rotational behavior.

    Inden, Masatoshi; Takata, Kazuyuki; Yanagisawa, Daijiro; Ashihara, Eishi; Tooyama, Ikuo; Shimohama, Shun; Kitamura, Yoshihisa

    2016-03-01

    Galantamine, an acetylcholine esterase (AChE) inhibitor used to treat dementia symptoms, also acts as an allosteric potentiating ligand (APL) at nicotinic acetylcholine receptors (nAChRs). This study was designed to evaluate the allosteric effect of galantamine on nAChR regulation of nigrostrial dopaminergic neuronal function in the hemiparkinsonian rat model established by unilateral nigral 6-hydroxydopamine (6-OHDA) injection. Methamphetamine, a dopamine releaser, induced ipsilateral rotation, whereas dopamine agonists apomorphine (a non-selective dopamine receptor agonist), SKF38393 (a selective dopamine D1 receptor agonist), and quinpirole (a selective dopamine D2 receptor agonist) induced contralateral rotation. When 6-OHDA-injected rats were co-treated with nomifensine, a dopamine transporter inhibitor, a more pronounced and a remarkable effect of nicotine and galantamine was observed. Under these conditions, the combination of nomifensine with nicotine or galantamine induced the ipsilateral rotation similar to the methamphetamine-induced rotational behavior, indicating that nicotine and galantamine also induce dopamine release from striatal terminals. Both nicotine- and galantamine-induced rotations were significantly blocked by flupenthixol (an antagonist of both D1 and D2 dopamine receptors) and mecamylamine (an antagonist of nAChRs), suggesting that galantamine modulation of nAChRs on striatal dopaminergic terminals regulates dopamine receptor-mediated movement. Immunohistochemical staining showed that α4 nAChRs were highly expressed on striatal dopaminergic terminals, while no α7 nAChRs were detected. Pretreatment with the α4 nAChR antagonist dihydroxy-β-erythroidine significantly inhibited nicotine- and galantamine-induced rotational behaviors, whereas pretreatment with the α7 nAChR antagonist methyllycaconitine was ineffective. Moreover, the α4 nAChR agonist ABT-418 induced ipsilateral rotation, while the α7 nAChR agonist PNU282987 had no

  12. Electrical detection of spin transport in Si two-dimensional electron gas systems

    Chang, Li-Te; Fischer, Inga Anita; Tang, Jianshi; Wang, Chiu-Yen; Yu, Guoqiang; Fan, Yabin; Murata, Koichi; Nie, Tianxiao; Oehme, Michael; Schulze, Jörg; Wang, Kang L.

    2016-09-01

    Spin transport in a semiconductor-based two-dimensional electron gas (2DEG) system has been attractive in spintronics for more than ten years. The inherent advantages of high-mobility channel and enhanced spin–orbital interaction promise a long spin diffusion length and efficient spin manipulation, which are essential for the application of spintronics devices. However, the difficulty of making high-quality ferromagnetic (FM) contacts to the buried 2DEG channel in the heterostructure systems limits the potential developments in functional devices. In this paper, we experimentally demonstrate electrical detection of spin transport in a high-mobility 2DEG system using FM Mn-germanosilicide (Mn(Si0.7Ge0.3)x) end contacts, which is the first report of spin injection and detection in a 2DEG confined in a Si/SiGe modulation doped quantum well structure (MODQW). The extracted spin diffusion length and lifetime are l sf = 4.5 μm and {τ }{{s}}=16 {{ns}} at 1.9 K respectively. Our results provide a promising approach for spin injection into 2DEG system in the Si-based MODQW, which may lead to innovative spintronic applications such as spin-based transistor, logic, and memory devices.

  13. Transport

    Transport is one of the major causes of environmental damage in Austria. Energy consumption, pollutants emissions, noise emissions, use of surfaces, sealing of surfaces, dissection of ecosystems and impact on landscape are the most significant environmental impacts caused by it. An overview of the transport development of passengers and freight in Austria is presented. Especially the energy consumption growth, carbon dioxide and nitrogen oxide emissions by type of transport, and the emissions development (HC, particle and carbon monoxide) of goods and passengers transport are analyzed covering the years 1980 - 1999. The health cost resulting from transport-related air pollution in Austria is given and measures to be taken for an effective control of the transport sector are mentioned. Figs. 8, Table 1. (nevyjel)

  14. Transport simulation and image reconstruction for fast-neutron detection of explosives and narcotics

    Micklich, B.J.; Fink, C.L.; Sagalovsky, L.

    1995-07-01

    Fast-neutron inspection techniques show considerable promise for explosive and narcotics detection. A key advantage of using fast neutrons is their sensitivity to low-Z elements (carbon, nitrogen, and oxygen), which are the primary constituents of these materials. We are currently investigating two interrogation methods in detail: Fast-Neutron Transmission Spectroscopy (FNTS) and Pulsed Fast-Neutron Analysis (PFNA). FNTS is being studied for explosives and narcotics detection in luggage and small containers for which the transmission ratio is greater than about 0.01. The Monte-Carlo radiation transport code MCNP is being used to simulate neutron transmission through a series of phantoms for a few (3-5) projection angles and modest (2 cm) resolution. Areal densities along projection rays are unfolded from the transmission data. Elemental abundances are obtained for individual voxels by tomographic reconstruction, and these reconstructed elemental images are combined to provide indications of the presence or absence of explosives or narcotics. PFNA techniques are being investigated for detection of narcotics in cargo containers because of the good penetration of the fast neutrons and the low attenuation of the resulting high-energy gamma-ray signatures. Analytic models and Monte-Carlo simulations are being used to explore the range of capabilities of PFNA techniques and to provide insight into systems engineering issues. Results of studies from both FNTS and PFNA techniques are presented.

  15. Organophosphate acetylcholine esterase inhibitor poisoning from a home-made shampoo

    Sadaka, Yair; Broides, Arnon; Tzion, Raffi Lev; Lifshitz, Matitiahu

    2011-01-01

    Organophosphate acetylcholine esterase inhibitor poisoning is a major health problem in children. We report an unusual cause of organophosphate acetylcholine esterase inhibitor poisoning. Two children were admitted to the pediatric intensive care unit due to organophosphate acetylcholine esterase inhibitor poisoning after exposure from a home-made shampoo that was used for the treatment of head lice. Owing to no obvious source of poisoning, the diagnosis of organophosphate acetylcholine ester...

  16. Flavonoids with M1 Muscarinic Acetylcholine Receptor Binding Activity

    Meyyammai Swaminathan

    2014-06-01

    Full Text Available Muscarinic acetylcholine receptor-active compounds have potential for the treatment of Alzheimer’s disease. In this study, a series of natural and synthetic flavones and flavonols was assayed in vitro for their ability to inhibit radioligand binding at human cloned M1 muscarinic receptors. Several compounds were found to possess competitive binding affinity (Ki = 40–110 µM, comparable to that of acetylcholine (Ki = 59 µM. Despite the fact that these compounds lack a positively-charged ammonium group under physiological conditions, molecular modelling studies suggested that they bind to the orthosteric site of the receptor, mainly through non-polar interactions.

  17. Expression of the α7 nicotinic acetylcholine receptor in human lung cells

    Schuller Hildegard M

    2005-04-01

    Full Text Available Abstract Background We and others have shown that one of the mechanisms of growth regulation of small cell lung cancer cell lines and cultured pulmonary neuroendocrine cells is by the binding of agonists to the α7 neuronal nicotinic acetylcholine receptor. In addition, we have shown that the nicotine-derived carcinogenic nitrosamine, 4(methylnitrosamino-1-(3-pyridyl-1-butanone (NNK, is a high affinity agonist for the α7 nicotinic acetylcholine receptor. In the present study, our goal was to determine the extent of α7 mRNA and protein expression in the human lung. Methods Experiments were done using reverse transcription polymerase chain reaction (RT-PCR, a nuclease protection assay and western blotting using membrane proteins. Results We detected mRNA for the neuronal nicotinic acetylcholine receptor α7 receptor in seven small cell lung cancer (SCLC cell lines, in two pulmonary adenocarcinoma cell lines, in cultured normal human small airway epithelial cells (SAEC, one carcinoid cell line, three squamous cell lines and tissue samples from nine patients with various types of lung cancer. A nuclease protection assay showed prominent levels of α7 in the NCI-H82 SCLC cell line while α7 was not detected in SAEC, suggesting that α7 mRNA levels may be higher in SCLC compared to normal cells. Using a specific antibody to the α7 nicotinic receptor, protein expression of α7 was determined. All SCLC cell lines except NCI-H187 expressed protein for the α7 receptor. In the non-SCLC cells and normal cells that express the α7 nAChR mRNA, only in SAEC, A549 and NCI-H226 was expression of the α7 nicotinic receptor protein shown. When NCI-H69 SCLC cell line was exposed to 100 pm NNK, protein expression of the α7 receptor was increased at 60 and 150 min. Conclusion Expression of mRNA for the neuronal nicotinic acetylcholine receptor α7 seems to be ubiquitously expressed in all human lung cancer cell lines tested (except for NCI-H441 as well as normal

  18. Piezo-microfluidic transport system for multi-targets biochip detections

    Li, Chia-Chin; Wang, Pei-Wen; Lee, Chih-Kung

    2016-03-01

    Detecting minute trace of interferon-gamma and various bio-markers by using a single biochip was adopted as a platform to examine the technology advancements presented. As bio-detection faces the restriction that only very small quantity of specimen is available, ways to make the best use of the sample available are a must. Since samples concentration will affect the binding rate of an immunoassay, the testing order will become an influencing factor if multiple biomarkers testing situation are needed by using only a single trace of sample. More specifically, if we test disease A first and then detect disease B using the sample just been measured by testing disease A, we most likely will get different results if we reverse the testing order. With an attempt to examine and maybe resolve the issues mentioned above, a micro-fluid control system was developed. The design requirements not only ask for microfluidic control but also demand the system developed has the potential to be integrated within the biochip once its performance is verified. A piezo-vibrating system that can generate traveling waves for microfluidic control was chosen due to its versatility and large force to volume ratio. A simulation software COMSOL was adopted first to predict the microfluidic behavior of the two-mode excited piezo-microfluidic transport system. Secondly, fluorescent particles was used to analyze the microfluidic behavior of system fabricated based on the simulation. Finally, Electrochemistry Impedance Spectroscopy (EIS) was implemented to verify the performance and extendibility of this newly developed system for multi-target detections.

  19. Sensitive and transportable gadolinium-core plastic scintillator sphere for neutron detection and counting

    Dumazert, Jonathan; Coulon, Romain; Carrel, Frédérick; Corre, Gwenolé; Normand, Stéphane; Méchin, Laurence; Hamel, Matthieu

    2016-08-01

    Neutron detection forms a critical branch of nuclear-related issues, currently driven by the search for competitive alternative technologies to neutron counters based on the helium-3 isotope. The deployment of plastic scintillators shows a high potential for efficient detectors, safer and more reliable than liquids, more easily scalable and cost-effective than inorganic. In the meantime, natural gadolinium, through its 155 and mostly 157 isotopes, presents an exceptionally high interaction probability with thermal neutrons. This paper introduces a dual system including a metal gadolinium core inserted at the center of a high-scale plastic scintillator sphere. Incident fast neutrons are thermalized by the scintillator shell and then may be captured with a significant probability by gadolinium 155 and 157 nuclei in the core. The deposition of a sufficient fraction of the capture high-energy prompt gamma signature inside the scintillator shell will then allow discrimination from background radiations by energy threshold, and therefore neutron detection. The scaling of the system with the Monte Carlo MCNPX2.7 code was carried out according to a tradeoff between the moderation of incident fast neutrons and the probability of slow neutron capture by a moderate-cost metal gadolinium core. Based on the parameters extracted from simulation, a first laboratory prototype for the assessment of the detection method principle has been synthetized. The robustness and sensitivity of the neutron detection principle are then assessed by counting measurement experiments. Experimental results confirm the potential for a stable, highly sensitive, transportable and cost-efficient neutron detector and orientate future investigation toward promising axes.

  20. Generation, transport and detection of valley-polarized electrons in diamond.

    Isberg, Jan; Gabrysch, Markus; Hammersberg, Johan; Majdi, Saman; Kovi, Kiran Kumar; Twitchen, Daniel J

    2013-08-01

    Standard electronic devices encode bits of information by controlling the amount of electric charge in the circuits. Alternatively, it is possible to make devices that rely on other properties of electrons than their charge. For example, spintronic devices make use of the electron spin angular momentum as a carrier of information. A new concept is valleytronics in which information is encoded by the valley quantum number of the electron. The analogy between the valley and spin degrees of freedom also implies the possibility of valley-based quantum computing. In this Article, we demonstrate for the first time generation, transport (across macroscopic distances) and detection of valley-polarized electrons in bulk diamond with a relaxation time of 300 ns at 77 K. We anticipate that these results will form the basis for the development of integrated valleytronic devices. PMID:23852401

  1. Tissue-specific effects of acetylcholine in the canine heart

    Callø, Kirstine; Goodrow, Robert; Olesen, Søren-Peter;

    2013-01-01

    INTRODUCTION: Acetylcholine (ACh) release from the vagus nerve slows heart rate and atrioventricular conduction. ACh stimulates a variety of receptors and channels, including an inward rectifying current (IK,ACh). The effect of ACh in ventricle is still debated. We compare the effect of ACh on...

  2. Functional partial agonism at cloned human muscarinic acetylcholine receptors

    Bräuner-Osborne, Hans; Ebert, B; Brann, M R;

    1996-01-01

    of maximal response, depending on the molar ratio of agonist and antagonist used. Using recombinant human muscarinic acetylcholine receptors (m1 and m5) and the functional assay, receptor selection and amplification technology (R-SAT), we have now shown that co-administration of the full agonist...

  3. Detecting the local transport properties and the dimensionality of transport of epitaxial graphene by a multi-point probe approach

    Barreto, Lucas; Perkins, Edward; Johannsen, Jens;

    2013-01-01

    The electronic transport properties of epitaxial monolayer graphene (MLG) and hydrogen-intercalated quasi free-standing bilayer graphene (QFBLG) on SiC(0001) are investigated by micro multi-point probes. Using a probe with 12 contacts, we perform four-point probe measurements with the possibility...... to effectively vary the contact spacing over more than one order of magnitude, allowing us to establish that the transport is purely two-dimensional. Combined with the carrier density obtained by angle-resolved photoemission spectroscopy, we find the room temperature mobility of MLG to be (870...

  4. Detection of smuggling of nuclear material covered by a legal transport of radioactive material

    Full text: One of the worst scenarios for detection of illicit trafficking of nuclear material is when a legal transport of radioactive material is used to cover the radiation of the smuggled uranium. Feasibility study was performed in the Institute of Isotopes and Surface Chemistry of the Chemical Research Centre of the Hungarian Academy of Sciences (hereinafter: Institute) in order to study the possible on site measurement techniques and approaches applicable in such cases. As the type A and type B packages always incorporate a feature such as a seal, in a realistic scenario the confiscated nuclear material is expected to be placed outside the package. The passive neutron emission of the uranium is negligible for a reasonable isotopic abundance therefore the feasibility study was concentrating on non-destructive, passive gamma- spectrometric methods. Possible application of Nal (diameter 40x40 mm3, large planar (15x15x3 mm3) and a hemispheric CdZnTe (500 mm3, and high purity Germanium detectors was investigated. During the on site measurements portable electronics, mini multichannel analyzer, palmtop and/or notebook computer were used. The shielding material of the packages was lead or depleted uranium. The smuggled material was simulated by a package of reactor fuel pellets containing low enriched or natural uranium (materials confiscated in earlier cases) and standards containing low enriched uranium. During the supposed scenario the portal monitor provides an indication of an elevated level of the environmental radioactivity. Then the responsible (e.g. customs) officer investigate the vehicle by a hand-held survey meter in order to search for peaks in dose rates. If a peak was localized, which is different from the position of the legally transported package(s) the officer requests for the expertise of the designated institutes. The following model cases provided the basic conclusion: 1. The legal transport of the radioactive material was simulated by a 4

  5. Comparison of the activation kinetics of the M3 acetylcholine receptor and a constitutively active mutant receptor in living cells.

    Hoffmann, Carsten; Nuber, Susanne; Zabel, Ulrike; Ziegler, Nicole; Winkler, Christiane; Hein, Peter; Berlot, Catherine H; Bünemann, Moritz; Lohse, Martin J

    2012-08-01

    Activation of G-protein-coupled receptors is the first step of the signaling cascade triggered by binding of an agonist. Here we compare the activation kinetics of the G(q)-coupled M(3) acetylcholine receptor (M(3)-AChR) with that of a constitutively active mutant receptor (M(3)-AChR-N514Y) using M(3)-AChR constructs that report receptor activation by changes in the fluorescence resonance energy transfer (FRET) signal. We observed a leftward shift in the concentration-dependent FRET response for acetylcholine and carbachol with M(3)-AChR-N514Y. Consistent with this result, at submaximal agonist concentrations, the activation kinetics of M(3)-AChR-N514Y were significantly faster, whereas at maximal agonist concentrations the kinetics of receptor activation were identical. Receptor deactivation was significantly faster with carbachol than with acetylcholine and was significantly delayed by the N514Y mutation. Receptor-G-protein interaction was measured by FRET between M(3)-AChR-yellow fluorescent protein (YFP) and cyan fluorescent protein (CFP)-Gγ(2). Agonist-induced receptor-G-protein coupling was of a time scale similar to that of receptor activation. As observed for receptor deactivation, receptor-G-protein dissociation was slower for acetylcholine than that for carbachol. Acetylcholine-stimulated increases in receptor-G-protein coupling of M(3)-AChR-N514Y reached only 12% of that of M(3)-AChR and thus cannot be kinetically analyzed. G-protein activation was measured using YFP-tagged Gα(q) and CFP-tagged Gγ(2). Activation of G(q) was significantly slower than receptor activation and indistinguishable for the two agonists. However, G(q) deactivation was significantly prolonged for acetylcholine compared with that for carbachol. Consistent with decreased agonist-stimulated coupling to G(q), agonist-stimulated G(q) activation by M(3)-AChR-N514Y was not detected. Taken together, these results indicate that the N514Y mutation produces constitutive activation of M(3

  6. Polyester with Pendent Acetylcholine-Mimicking Functionalities Promotes Neurite Growth.

    Wang, Shaofei; Jeffries, Eric; Gao, Jin; Sun, Lijie; You, Zhengwei; Wang, Yadong

    2016-04-20

    Successful regeneration of nerves can benefit from biomaterials that provide a supportive biochemical and mechanical environment while also degrading with controlled inflammation and minimal scar formation. Herein, we report a neuroactive polymer functionalized by covalent attachment of the neurotransmitter acetylcholine (Ach). The polymer was readily synthesized in two steps from poly(sebacoyl diglyceride) (PSeD), which previously demonstrated biocompatibility and biodegradation in vivo. Distinct from prior acetylcholine-biomimetic polymers, PSeD-Ach contains both quaternary ammonium and free acetyl moieties, closely resembling native acetylcholine structure. The polymer structure was confirmed via (1)H nuclear magnetic resonance and Fourier-transform infrared spectroscopy. Hydrophilicity, charge, and thermal properties of PSeD-Ach were determined by tensiometer, zetasizer, differential scanning calorimetry, and thermal gravimetric analysis, respectively. PC12 cells exhibited the greatest proliferation and neurite outgrowth on PSeD-Ach and laminin substrates, with no significant difference between these groups. PSeD-Ach yielded much longer neurite outgrowth than the control polymer containing ammonium but no the acetyl group, confirming the importance of the entire acetylcholine-like moiety. Furthermore, PSeD-Ach supports adhesion of primary rat dorsal root ganglions and subsequent neurite sprouting and extension. The sprouting rate is comparable to the best conditions from previous report. Our findings are significant in that they were obtained with acetylcholine-like functionalities in 100% repeating units, a condition shown to yield significant toxicity in prior publications. Moreover, PSeD-Ach exhibited favorable mechanical and degradation properties for nerve tissue engineering application. Humidified PSeD-Ach had an elastic modulus of 76.9 kPa, close to native neural tissue, and could well recover from cyclic dynamic compression. PSeD-Ach showed a gradual in

  7. Positive cooperativity of acetylcholine and other agonists with allosteric ligands on muscarinic acetylcholine receptors.

    Jakubík, J; Bacáková, L; El-Fakahany, E E; Tucek, S

    1997-07-01

    It is well known that allosteric modulators of muscarinic acetylcholine receptors can both diminish and increase the affinity of receptors for their antagonists. We investigated whether the allosteric modulators can also increase the affinity of receptors for their agonists. Twelve agonists and five allosteric modulators were tested in experiments on membranes of CHO cells that had been stably transfected with genes for the M1-M4 receptor subtypes. Allosterically induced changes in the affinities for agonists were computed from changes in the ability of a fixed concentration of each agonist to compete with [3H]N-methylscopolamine for the binding to the receptors in the absence and the presence of varying concentrations of allosteric modulators. The effects of allosteric modulators varied greatly depending on the agonists and the subtypes of receptors. The affinity for acetylcholine was augmented by (-)-eburnamonine on the M2 and M4 receptors and by brucine on the M1 and M3 receptors. Brucine also enhanced the affinities for carbachol, bethanechol, furmethide, methylfurmethide, pilocarpine, 3-(3-pentylthio-1,2,5-thiadiazol-4-yl)-1,2,5,6-tetrahydro-1- methylpyridine (pentylthio-TZTP), oxotremorine-M, and McN-A-343 on the M1, M3, and M4 receptors, for pentylthio-TZTP on the M2 receptors, and for arecoline on the M3 receptors. (-)-Eburnamonine enhanced the affinities for carbachol, bethanechol, furmethide, methylfurmethide, pentylthio-TZTP, pilocarpine, oxotremorine and oxotremorine-M on the M2 receptors and for pilocarpine on the M4 receptors. Vincamine, strychnine, and alcuronium displayed fewer positive allosteric interactions with the agonists, but each allosteric modulator displayed positive cooperativity with at least one agonist on at least one muscarinic receptor subtype. The highest degrees of positive cooperativity were observed between (-)-eburnamonine and pilocarpine and (-)-eburnamonine and oxotremorine-M on the M2 receptors (25- and 7-fold increases in

  8. Micro and nanoscale electrochemical systems for reagent generation, coupled electrokinetic transport and enhanced detection

    Contento, Nicholas M.

    Chemical analysis is being performed in devices operated at ever decreasing length scales in order to harness the fundamental benefits of micro and nanoscale phenomena while minimizing operating footprint and sample size. The advantages of moving traditional sample or chemical processing steps (e.g. separation, detection, and reaction) into micro- and nanofluidic devices have been demonstrated, and they arise from the relatively rapid rates of heat and mass transport at small length scales. The use of electrochemical methods in micro/nanoscale systems to control and improve these processes holds great promise. Unfortunately, much is still not understood about the coupling of multiple electrode driven processes in a confined environment nor about the fundamental changes in device performance that occur as geometries approach the nanoscale regime. At the nanoscale a significant fraction of the sample volume is in close contact with the device surface, i.e. most of the sample is contained within electronic or diffusion layers associated with surface charge or surface reactions, respectively. The work presented in this thesis aims to understand some fundamental different behaviors observed in micro/nanofluidic structures, particularly those containing one or more embedded, metallic electrode structures. First, a quantitative method is devised to describe the impact of electric fields on electrochemistry in multi-electrode micro/nanofluidic systems. Next the chemical manipulation of small volumes (≤ 10-13 L) in micro/nanofluidic structures is explored by creating regions of high pH and high dissolved gas (H 2) concentration through the electrolysis of H2O. Massively parallel arrays of nanochannel electrodes, or embedded annular nanoband electrodes (EANEs), are then studied with a focus on achieving enhanced signals due to coupled electrokinetic and electrochemical effects. In EANE devices, electroosmotic flow results from the electric field generated between the

  9. Acetylcholine Protects against Candida albicans Infection by Inhibiting Biofilm Formation and Promoting Hemocyte Function in a Galleria mellonella Infection Model

    Rajendran, R.; Borghi, E.; M. Falleni; F Perdoni; Tosi, D.; D.F. Lappin; L. O'Donnell; Greetham, D.; G. Ramage; C. Nile

    2015-01-01

    Both neuronal acetylcholine and nonneuronal acetylcholine have been demonstrated to modulate inflammatory responses. Studies investigating the role of acetylcholine in the pathogenesis of bacterial infections have revealed contradictory findings with regard to disease outcome. At present, the role of acetylcholine in the pathogenesis of fungal infections is unknown. Therefore, the aim of this study was to determine whether acetylcholine plays a role in fungal biofilm formation and the pathoge...

  10. Coupling the Torpedo Microplate-Receptor Binding Assay with Mass Spectrometry to Detect Cyclic Imine Neurotoxins

    Aráoz, Rómulo; Ramos, Suzanne; Pelissier, Franck; Guérineau, Vincent; Benoit, Evelyne; Vilariño, Natalia; Botana, Luis M.; Zakarian, Armen; Molgó, Jordi

    2012-01-01

    Cyclic imine neurotoxins constitute an emergent family of neurotoxins of dinoflagellate origin that are potent antagonists of nicotinic acetylcholine receptors. We developed a target-directed functional method based on the mechanism of action of competitive agonists/antagonists of nicotinic acetylcholine receptors for the detection of marine cyclic imine neurotoxins. The key step for method development was the immobilization of Torpedo electrocyte membranes rich in nicotinic acetylcholine rec...

  11. Detection of follicular transport of lidocaine and metabolism in adipose tissue in pig ear skin by DESI mass spectrometry imaging

    D'Alvise, Janina; Mortensen, Rasmus; Hansen, Steen H;

    2014-01-01

    Desorption electrospray ionization (DESI) mass spectrometry imaging is demonstrated as a detection technique for penetration experiments of drugs in skin. Lidocaine ointment was used as the model compound in ex vivo experiments with whole pig ears as the skin model. Follicular transport of...

  12. The use of neutron generators for the detection of illicit materials in the sea transportation system

    In today's society acts of terrorism must involve in some stages the illicit trafficking either of explosives, chemical agents and/or nuclear materials. Therefore society must rely on an anti-trafficking infrastructure which encompasses responsible authorities, field personnel and adequate instrumental networks. Modern inspection systems for personnel, parcel, vehicle and cargo, as noninvasive imaging techniques, are based on the use of nuclear analytical methods. The inspection systems make use of penetrating radiation (neutrons, gamma and x-rays) in a scanning geometry, with the detection of radiation either transmitted or produced in the interrogated object. Explosives and chemical agent detection systems are based on the fact that the problem of identification can be reduced to the measurement of elemental concentrations. Different nuclear analytical techniques could be used for this purpose; however the use of neutrons has some specific advantages due to the high penetrability in large payloads. Of special interest is the design and use of a transportable neutron system coupled to a gamma-ray radiographic device for inspecting large containers searching for contraband, explosives, weapons etc. The use of neutron induced reactions for non-destructive bulk elemental analysis is well documented. All neutrons, in particular fast neutrons, are well suited to explore large volume samples because of their high penetration in bulk material. Fast neutrons can be produced efficiently and economically by natural radioactive sources, small accelerators or compact electronic neutron generators, making possible the use of neutron based techniques in field applications. Gamma-rays produced by irradiating the sample with neutrons gives the elemental composition of the material, moreover, knowing the nuclear cross-sections and estimating the absorption factors in the different materials, it is possible to perform a quantitative analysis of elements in the sample even in depth

  13. Localization of muscarinic acetylcholine receptor in plant guard cells

    2001-01-01

    Acetylcholine (ACh), as an important neurotransmitter in animals, also plays a significant role in various kinds of physiological functions in plants. But relatively little is known about its receptors in plants. A green fluorescence BODIPY FL-labeled ABT, which is a high affinity ligand of muscarinic acetylcholine receptor (mAChR), was used to localize mAChR in plant guard cells. In Vicia faba L. and Pisum sativum L., mAChR was found both on the plasma membrane of guard cells. mAChR may also be distributed on guard cell chloroplast membrane of Vicia faba L. The evidence that mAChR localizes in the guard cells provides a new possible signal transduction pathway in ACh mediated stomata movement.

  14. Structures of acetylcholine picrate and methoxycarbonylcholine picrate hemihydrate

    Frydenvang, Karla Andrea; Grønborg, L; Jensen, B

    Acetylcholine picrate, C7H16NO2+.C6H2N3-O7-, Mr = 374.3, orthorhombic, Pbca, at 105 K: a = 18.799 (4), b = 7.726 (2), c = 22.878 (4) A, V = 3323 (2) A3, Z = 8, Dm(295 K, flotation) = 1.44, D chi(105 K) = 1.496 Mg m-3, mu(Mo K alpha) = 0.120 mm-1, F(000) = 1568, m.p. (hot-stage microscope) 381-382 K......(295 K, flotation) = 1.49, D chi(105 K) = 1.539 Mg m-3, mu(Mo K alpha) = 0.126 mm-1, F(000) = 836, m.p. (hot-stage microscope) 391-391.5 K, R = 0.033 for 6359 observed [I greater than or equal to 3.0 sigma(I)] reflections. The acetylcholine ion as well as the methoxycarbonylcholine ion have as first...

  15. Leukocytic acetylcholine in chronic rejection of renal allografts

    Wilczynska, Joanna

    2011-01-01

    Leukocytes, which accumulate in graft blood vessels during fatal acute rejection of experimental renal allografts, synthesise and release acetylcholine (ACh). In this study, I tested the hypothesis that ACh produced by leukocytes accumulating in graft blood vessels contributes to the pathogenesis of chronic renal allograft vasculopathy (CAV). Kidneys were transplanted in the allogeneic Fischer 344 to Lewis rat strain combination. Isogeneic transplantations were performed in Lew...

  16. Long release latencies are increased by acetylcholine at frog endplate

    Samigullin, D.; Bukharaeva, E. A.; Nikolsky, E.; Adámek, S.; Vyskočil, František

    2003-01-01

    Roč. 52, č. 4 (2003), s. 475-480. ISSN 0862-8408 R&D Projects: GA ČR GA305/02/1333; GA ČR GA202/02/1213 Grant ostatní: RFBR(RU) 02/04/48901 Institutional research plan: CEZ:AV0Z5011922; CEZ:MSM 113100003 Keywords : quantal release * acetylcholine * synaptic latency Subject RIV: ED - Physiology Impact factor: 0.939, year: 2003

  17. Threonine in the selectivity filter of the acetylcholine receptor channel.

    Villarroel, A.; Sakmann, B

    1992-01-01

    The acetylcholine receptor (AChR) is a cation selective channel whose biophysical properties as well as its molecular composition are fairly well characterized. Previous studies on the rat muscle alpha-subunit indicate that a threonine residue located near the cytoplasmic side of the M2 segment is a determinant of ion flow. We have studied the role of this threonine in ionic selectivity by measuring conductance sequences for monovalent alkali cations and bionic reversal potentials of the wild...

  18. Subtype Differences in Pre-Coupling of Muscarinic Acetylcholine Receptors

    Jakubík, Jan; Janíčková, Helena; Randáková, Alena; El-Fakahany, E. E.; Doležal, Vladimír

    2011-01-01

    Roč. 6, č. 11 (2011), e27732. E-ISSN 1932-6203 R&D Projects: GA ČR(CZ) GA305/09/0681; GA AV ČR(CZ) IAA500110703; GA MŠk(CZ) LC554 Institutional research plan: CEZ:AV0Z50110509 Keywords : acetylcholine muscarinic receptors * G proteins * subtype differences Subject RIV: ED - Physiology Impact factor: 4.092, year: 2011

  19. Alteration in cellular acetylcholine influences dauer formation in Caenorhabditis elegans

    Lee, Jeeyong; Kim, Kwang-Youl; Paik, Young-Ki

    2014-01-01

    Altered acetylcholine (Ach) homeostasis is associated with loss of viability in flies, developmental defects in mice, and cognitive deficits in human. Here, we assessed the importance of Ach in Caenorhabditis elegans development, focusing on the role of Ach during dauer formation. We found that dauer formation was disturbed in choline acetyltransferase (cha-1) and acetylcholinesterase (ace) mutants defective in Ach biosynthesis and degradation, respectively. When examined the potential role o...

  20. New Insights on Plant Cell Elongation: A Role for Acetylcholine

    Gian-Pietro Di Sansebastiano; Silvia Fornaciari; Fabrizio Barozzi; Gabriella Piro; Laura Arru

    2014-01-01

    We investigated the effect of auxin and acetylcholine on the expression of the tomato expansin gene LeEXPA2, a specific expansin gene expressed in elongating tomato hypocotyl segments. Since auxin interferes with clathrin-mediated endocytosis, in order to regulate cellular and developmental responses we produced protoplasts from tomato elongating hypocotyls and followed the endocytotic marker, FM4-64, internalization in response to treatments. Tomato protoplasts were observed during auxin and...

  1. Travel path and transport mode identification method using ''less-frequently-detected'' position data

    This study aims to seek method on travel path and transport mode identification in case positions of travellers are detected in low frequency. The survey in which ten test travellers with GPS logger move around Tokyo city centre was conducted. Travel path datasets of each traveller in which position data are selected every five minutes are processed from our survey data. Coverage index analysis based on the buffer analysis using GIS software is conducted. The condition and possibility to identify a path and a transport mode used are discussed

  2. Mutants of the Base Excision Repair Glycosylase, Endonuclease III: DNA Charge Transport as a First Step in Lesion Detection

    Romano, Christine A.; Sontz, Pamela A.; Barton, Jacqueline K.

    2011-01-01

    Endonuclease III (EndoIII) is a base excision repair glycosylase that targets damaged pyrimidines and contains a [4Fe-4S] cluster. We have proposed a model where BER proteins that contain redox-active [4Fe-4S] clusters utilize DNA charge transport (CT) as a first step in the detection of DNA lesions. Here, several mutants of EndoIII were prepared to probe their efficiency of DNA/protein charge transport. Cyclic voltammetry experiments on DNA-modified electrodes show that aromatic residues F30...

  3. A new family of insect muscarinic acetylcholine receptors.

    Xia, R-Y; Li, M-Q; Wu, Y-S; Qi, Y-X; Ye, G-Y; Huang, J

    2016-08-01

    Most currently used insecticides are neurotoxic chemicals that target a limited number of sites and insect cholinergic neurotransmission is the major target. A potential target for insecticide development is the muscarinic acetylcholine receptor (mAChR), which is a metabotropic G-protein-coupled receptor. Insects have A- and B-type mAChRs and the five mammalian mAChRs are close to the A-type. We isolated a cDNA (CG12796) from the fruit fly, Drosophila melanogaster. After heterologous expression in Chinese hamster ovary K1 cells, CG12796 could be activated by acetylcholine [EC50 (half maximal effective concentration), 73 nM] and the mAChR agonist oxotremorine M (EC50 , 48.2 nM) to increase intracellular Ca(2+) levels. Thus, the new mAChR is coupled to Gq/11 but not Gs and Gi/o . The classical mAChR antagonists atropine and scopolamine N-butylbromide at 100 μM completely blocked the acetylcholine-induced responses. The orthologues of CG12796 can also be found in the genomes of other insects, but not in the genomes of the honeybee or parasitoid wasps. Knockdown of CG12796 in the central nervous system had no effect on male courtship behaviours. We suggest that CG12796 represents the first recognized member of a novel mAChR class. PMID:27003873

  4. Gold nanoparticle–choline complexes can block nicotinic acetylcholine receptors

    Chur Chin

    2010-04-01

    Full Text Available Chur Chin1, In Kyeom Kim2, Dong Yoon Lim3, Ki Suk Kim4, Hyang Ae Lee4, Eun Joo Kim41Department of Pediatrics, Fatima Hospital, Daegu, Korea; 2Department of Pharmacology, School of Medicine, Kyungpook National University, Daegu, Korea; 3Department of Pharmacology, School of Medicine, Chosun University, Gwangju, Korea; 4Korea Institute of Toxicology, Daejeon, KoreaAbstract: We identified a novel class of direct ion-channel blockers of ligand-gated ion channels called the gold nanoparticle–choline complex. Negatively charged gold nanoparticles (1.4 nm block ion pores by binding to the sulfur group of the cysteine loop of nicotinic acetylcholine receptors (nAChRs, and currents evoked by acetylcholine (Ach can break these bonds. The current evoked by ACh in nAChRs was blocked directly in ion pores by the gold nanoparticle–choline complex. In adrenal-gland perfusion studies, the complex also blocked nAChRs by diminishing catecholamine release by about 75%. An in vivo study showed muscle relaxation in rats after injection of the complex. These results will foster the application of gold nanoparticles as a direct ion-channel blocker. Keywords: negatively charged gold nanoparticle, choline, gold–sulfur bond, nicotinic acetylcholine receptor, direct ion-channel blocker

  5. Comparison of [3H]nicotine and [3H]acetylcholine binding in mouse brain: regional distribution

    In a continuing study of nicotine binding sites, the authors determined the relative amount of nicotine binding and acetylcholine binding in various brain regions of C57/BL and of DBA mice. Although midbrain showed the highest and cerebellum the lowest binding for both [3H]nicotine and [3H]acetylcholine, the ratio of nicotine to acetylcholine binding showed a three-fold regional variation. Acetylcholine inhibition of [3H]nicotine binding indicated that a portion of nicotine binding was not inhibited by acetylcholine. These results indicate important differences between the binding of (+/-)-[3H]nicotine and that of [3H]acetylcholine

  6. Effects of cooling on the response of the snail bursting neuron to acetylcholine.

    Nedeljković, Miodrag; Kartelija, Gordana; Radenović, Lidija

    2005-06-01

    The Br-type neuron of the snail Helix pomatia, involved in neuronal regulation of various homeostatic and adaptive mechanisms, represents an interesting model for studying effects of temperature change on neuronal activity of poikilotherms. Acetylcholine induces a transient, inward dose-dependent current in the identified Br neuron. In the work presented, we analyzed the effects of cooling on the acetylcholine-induced inward current. The amplitude of acetylcholine-induced inward current was markedly decreased after cooling, and the speed of the decay of acetylcholine response was decreased. PMID:16154950

  7. Study of acetylcholine and barium receptors in the rat duodeno-jejunum by means of labelled molecules

    The purpose of this work is the determination of the number and the localization of Acetylcholine and Barium receptors in the rat intestine. We used 'radioactive labelled' drugs to reach a high sensitiveness of detection. So we were able to point out the number of 'effective' molecules of drugs, that is to say the only ones combining with receptors. With the aid of some assumptions, we determine on the one hand the receptors localization by an assessment of the drug penetration depth before reaching their level and on the other hand the number of these receptors. (author)

  8. Red Fluorescent Protein pH Biosensor to Detect Concentrative Nucleoside Transport*

    Johnson, Danielle E.; Ai, Hui-wang; Wong, Peter; Young, James D.; Campbell, Robert E.; Casey, Joseph R

    2009-01-01

    Human concentrative nucleoside transporter, hCNT3, mediates Na+/nucleoside and H+/nucleoside co-transport. We describe a new approach to monitor H+/uridine co-transport in cultured mammalian cells, using a pH-sensitive monomeric red fluorescent protein variant, mNectarine, whose development and characterization are also reported here. A chimeric protein, mNectarine fused to the N terminus of hCNT3 (mNect.hCNT3), enabled measurement of pH at the intracellular surface of hCNT3. mNectarine fluor...

  9. Habituation-Like Decrease of Acetylcholine-Induced Inward Current in Helix Command Neurons: Role of Microtubule Motor Proteins.

    Vasil'yeva, Natal'ya A; Murzina, Galina B; Pivovarov, Arkady S

    2015-07-01

    The role of kinesin and dynein microtubule-associated molecular motors in the cellular mechanism of depression of acetylcholine-induced inward chloride current (ACh-current) was examined in command neurons of land snails (Helix lucorum) in response to repeated applications of ACh to neuronal soma. This pharmacological stimulation imitated the protocol of tactile stimulation evoking behavioural habituation of the defensive reaction. In this system, a dynein inhibitor (erythro-9-(2-hydroxy-3-nonyl)adenine, 50 µM) decreased the ACh-current depression rate. Kinesin Eg5 inhibitors (Eg5 inhibitor III, 10 µM and Eg5 inhibitor V, trans-24, 15 µM) reduced the degree of current depression, and Eg5 inhibitor V also reduced the initial rate of depression. The results of electrophysiological experiments in combination with mathematical modelling provided evidence of the participation of dyneins and kinesin Eg5 proteins in the radial transport of acetylcholine receptors in command neurons of H. lucorum in the cellular analogue of habituation. Furthermore, these results suggest that the reciprocal interaction between dynein and kinesin proteins located on the same vesicle can lead to reverse their usual direction of transport (dyneins-in exocytosis and kinesin Eg5-in endocytosis). PMID:25687906

  10. Synthesis of poly(ester-carbonate) with a pendant acetylcholine analog for promoting neurite growth.

    Xing, Dongming; Ma, Lie; Gao, Changyou

    2014-10-01

    The modification of biodegradable polyesters with bioactive molecules has become an important strategy for controlling neuron adhesion and neurite outgrowth in nerve regeneration. In this study we report a biodegradable poly(ester-carbonate) with a pendant acetylcholine analog, which a neurotransmitter for the enhancement of neuron adhesion and outgrowth. The acetylcholine-functionalized poly(ester-carbonate) (Ach-P(LA-ClTMC)) was prepared by copolymerizing l-lactide (LA) and 5-methyl-5-chloroethoxycarbonyl trimethylene carbonate (ClTMC), followed by quaternization with trimethylamine. The acetylcholine analog content could be modulated by changing the molar feeding fraction of ClTMC. The incorporation of the acetylcholine analog improved the hydrophilicity of the films, but the acetylcholine analog content did not significantly influence the surface morphology of the acetylcholine-functionalized films. The results of PC12 cell culture showed that the acetylcholine analog promoted cell viability and neurite outgrowth in a concentration-dependent manner. The longest length of neurite and the percentage of cells bearing neurites were obtained on the Ach-P(LA-ClTMC)-10 film. All the results indicate that the integration of the acetylcholine analog at an appropriate fraction could be an effective strategy for optimizing the existing biodegradable polyesters for nerve regeneration applications. PMID:24998182

  11. Conformationally restrained carbamoylcholine homologues. Synthesis, pharmacology at neuronal nicotinic acetylcholine receptors and biostructural considerations

    de la Fuente Revenga, M; Balle, Thomas; Jensen, Anders A.; Frølund, Bente

    2015-01-01

    Exploration of small selective ligands for the nicotinic acetylcholine receptors (nAChRs) based on acetylcholine (ACh) has led to the development of potent agonists with clear preference for the α4β2 nAChR, the most prevalent nAChR subtype in the central nervous system. In this work we present the...

  12. Transport and Non-Invasive Position Detection of Electron Beams from Laser-Plasma Accelerators

    Osterhoff, Jens; Sokollik, Thomas; Nakamura, Kei; Bakeman, Michael; Weingartner, R; Gonsalves, Anthony; Shiraishi, Satomi; Lin, Chen; vanTilborg, Jeroen; Geddes, Cameron; Schroeder, Carl; Esarey, Eric; Toth, Csaba; DeSantis, Stefano; Byrd, John; Gruner, F; Leemans, Wim

    2011-07-20

    The controlled imaging and transport of ultra-relativistic electrons from laser-plasma accelerators is of crucial importance to further use of these beams, e.g. in high peak-brightness light sources. We present our plans to realize beam transport with miniature permanent quadrupole magnets from the electron source through our THUNDER undulator. Simulation results demonstrate the importance of beam imaging by investigating the generated XUV-photon flux. In addition, first experimental findings of utilizing cavity-based monitors for non-invasive beam-position measurements in a noisy electromagnetic laser-plasma environment are discussed.

  13. Histamine H3 receptors regulate acetylcholine release from the guinea pig ileum myenteric plexus

    The effect of selective histamine H3-receptor agonists and antagonists on the acetylcholine release from peripheral nerves was evaluated in the guinea pig longitudinal muscle-myenteric plexus preparations, preloaded with (3H)choline. In the presence of H1 and H2 blockade, histamine and (R)-α-methylhistamine inhibited the electrically-evoked acetylcholine release, being (R)-α-methylhistamine more active than histamine, but behaving as a partial agonist. The effect of histamine was completely reversed by selective H3-blocking drugs, thioperamide and impromidine, while only submaximal doses of (R)-α-methylhistamine were antagonized. Furthermore, thioperamide and impromidine enhanced the electrically-evoked acetylcholine release. On the contrary, the new H3-blocker, HST-7, was found substantially ineffective, both as histamine antagonist and as acetylcholine overflow enhancer. These data suggest that histamine exerts an inhibitory control on the acetylcholine release from intestinal cholinergic nerves through the activation of H3 receptors

  14. Novel compound, organic cation transporter 3 detection agent and organic cation transporter 3 activity inhibitor, WO2015002150 A1: a patent evaluation.

    Hu, Tao; Wang, Li; Pan, Xiaolei; Qi, Hualin

    2016-08-01

    Increasing pharmacological studies have demonstrated that organic cation transporter 3 (OCT3) plays an important role in controlling the extracellular concentrations of released monoamine neurotransmitter, suggesting that OCT3 might be a promising target in the treatment of depression. As a consequence, compounds showing inhibitory effects on the function of OCT3 have the potential for depression treatment. The current patent WO2015002150 A1 described the synthesis of 59 novel guanidine derivatives. All investigated compounds exhibited significant inhibitory effects (41.9-88.2%) on human OCT3 activity at 30 µM, using human OCT3-transfected human embryonic kidney 293 cell. Concentration-response curves (IC50 values) were determined for seven compounds with higher inhibition potency from the initial screening. IC50 values ranged from 1.9 to 24 µM. In addition, the concentration of these compound in aqueous solution with artificial membranes containing human OCT3 protein was measured. The concentration of compound 6 (SR-2045) was significantly reduced in the presence of human OCT3. Therefore, these compounds have the potential to be further developed as novel antidepressant and human OCT3 detection agent. Future investigations are needed to study the pharmacokinetic and pharmacological properties of these compounds and potential interaction with other transporters. PMID:27097290

  15. Detection and Quantification of Neurotransmitters in Dialysates

    Zapata, Agustin; Chefer, Vladimir I.; Shippenberg, Toni S.; Denoroy, Luc

    2009-01-01

    Sensitive analytical methods are needed for the separation and quantification of neurotransmitters obtained in microdialysate studies. This unit describes methods that permit quantification of nanomolar concentrations of monoamines and their metabolites (high-pressure liquid chromatography electrochemical detection), acetylcholine (HPLC-coupled to an enzyme reactor), and amino acids (HPLC-fluorescence detection; capillary electrophoresis with laser-induced fluorescence detection).

  16. Lane Detection in Video-Based Intelligent Transportation Monitoring via Fast Extracting and Clustering of Vehicle Motion Trajectories

    Jianqiang Ren

    2014-01-01

    Full Text Available Lane detection is a crucial process in video-based transportation monitoring system. This paper proposes a novel method to detect the lane center via rapid extraction and high accuracy clustering of vehicle motion trajectories. First, we use the activity map to realize automatically the extraction of road region, the calibration of dynamic camera, and the setting of three virtual detecting lines. Secondly, the three virtual detecting lines and a local background model with traffic flow feedback are used to extract and group vehicle feature points in unit of vehicle. Then, the feature point groups are described accurately by edge weighted dynamic graph and modified by a motion-similarity Kalman filter during the sparse feature point tracking. After obtaining the vehicle trajectories, a rough k-means incremental clustering with Hausdorff distance is designed to realize the rapid online extraction of lane center with high accuracy. The use of rough set reduces effectively the accuracy decrease, which results from the trajectories that run irregularly. Experimental results prove that the proposed method can detect lane center position efficiently, the affected time of subsequent tasks can be reduced obviously, and the safety of traffic surveillance systems can be enhanced significantly.

  17. Detection of pollution transport events southeast of Mexico City using ground-based visible spectroscopy measurements of nitrogen dioxide

    M. Grutter

    2009-07-01

    Full Text Available This work presents ground based differential optical absorption spectroscopy (DOAS measurements of nitrogen dioxide (NO2 during the MILAGRO field campaign in March 2006 at the Tenango del Aire research site located to the southeast of Mexico City. The DOAS NO2 column density measurements are used in conjunction with ceilometer, meteorological and surface nitric oxide (NO, nitrogen oxides (NOx and total reactive nitrogen (NOy measurements to analyze pollution transport events to the southeast of Mexico City during the MILARGO field campaign. The study divides the data set into three case study pollution transport events that occurred at the Tenango del Aire research site. The unique data set is then used to provide an in depth analysis of example days of each of the pollution transport events. An in depth analysis of 13 March 2006, a Case One day, shows the transport of several air pollution plumes during the morning through the Tenango del Aire research site when southerly winds are present and demonstrates how DOAS tropospheric NO2 vertical column densities (VCD, surface NO2 mixing ratios and ceilometer data are used to determine the vertical homogeneity of the pollution layer. The analysis of 18 March 2006, a Case Two day, shows that when northerly winds are present for the entire day, the air at the Tenango del Aire research site is relatively clean and no major pollution plumes are detected. Case 3 days are characterized by relatively clean air throughout the morning with large DOAS NO2 enhancements detected in the afternoon. The analysis of 28 March 2006 show the DOAS NO2 enhancements are likely due to lightning activity and demonstrate how suitable ground-based DOAS measruements are for monitoring anthropogenic and natural pollution sources that reside above the mixing layer.

  18. Adult celiac disease with acetylcholine receptor antibody positive myasthenia gravis

    Hugh J Freeman; Helen R Gillett; Peter M Gillett; Joel Oger

    2009-01-01

    Celiac disease has been associated with some autoimmune disorders. A 40-year-old competitive strongman with celiac disease responded to a glutenfree diet, but developed profound and generalized motor weakness with acetylcholine receptor antibody positive myasthenia gravis, a disorder reported to occur in about 1 in 5000. This possible relationship between myasthenia gravis and celiac disease was further explored in serological studies. Frozen stored serum samples from 23 acetylcholine receptor antibody positive myasthenia gravis patients with no intestinal symptoms were used to screen for celiac disease. Both endomysial and tissue transglutaminase antibodies were examined. One of 23 (or, about 4.3%) was positive for both IgA-endomysial and IgA tissue transglutaminase antibodies. Endoscopic studies subsequently showed duodenal mucosal scalloping and biopsies confirmed the histopathological changes of celiac disease. Celiac disease and myasthenia gravis may occur together more often than is currently appreciated. The presence of motor weakness in celiac disease may be a clue to occult myasthenia gravis, even in the absence of intestinal symptoms.

  19. Calcium transport by ionophorous peptides in dog and human lymphocytes detected by quin-2 fluorescence.

    Deber, C M; Hsu, L C

    1986-01-29

    Synthetic peptides of structure cyclo(Glu(OBz)-Sar-Gly-(N-R)Gly)2 (I), electrogenic Ca2+-selective carriers in phospholipid vesicle membranes, are shown to mediate the uptake of Ca2+ ions into the cytoplasm of dog and human lymphocytes. Ca2+ transport by DECYL-2E (I, R = n-decyl) - monitored by measurements of the fluorescence of an intracellular dye, quin-2 - occurred at a rate comparable to that produced by electroneutral Ca2+ ionophores ionomycin and Br-A23187. Fluorescence quenching experiments using Mn2+ suggested a greater selectivity by DECYL-2E for Ca2+/Mn2+ vs. the other two ionophores. The result that Ca2+ ions can traverse biological membranes bound in a neutral cavity consisting exclusively of peptide carbonyl ligands may imply the functional significance of binding sites of similar structures in membrane transport proteins. PMID:3947349

  20. Synthesis and characterization of valyloxy methoxy luciferin for the detection of valacyclovirase and peptide transporter.

    Walls, Zachary F; Gupta, Sheeba Varghese; Amidon, Gordon L; Lee, Kyung-Dall

    2014-10-15

    An amino acid ester derivative of luciferin (valoluc) was synthesized to mimic the transport and activation of valacyclovir. This molecule was characterized in vitro for specificity and enzymatic constants, and then assayed in two different, physiologically-relevant conditions. It was demonstrated that valoluc activation is sensitive to the same cellular factors as valacyclovir and thus has the potential to elucidate the dynamics of amino acid ester prodrug therapies in a functional, high-throughput manner. PMID:25240255

  1. Synthesis and Characterization of Valyloxy Methoxy Luciferin for the Detection of Valacyclovirase and Peptide Transporter

    Amidon, Gordon L.; Lee, Kyung-Dall

    2014-01-01

    An amino acid ester derivative of luciferin (valoluc) was synthesized to mimic the transport and activation of valacyclovir. This molecule was characterized in vitro for specificity and enzymatic constants, and then assayed in two different, physiologically-relevant conditions. It was demonstrated that valoluc activation is sensitive to the same cellular factors as valacyclovir and thus has the potential to elucidate the dynamics of amino acid ester prodrug therapies in a functional, high-throughput manner. PMID:25240255

  2. Quantitative Evaluation of an Air-monitoring Network Using Atmospheric Transport Modeling and Frequency of Detection Methods.

    Rood, Arthur S; Sondrup, A Jeffrey; Ritter, Paul D

    2016-04-01

    A methodology has been developed to quantify the performance of an air-monitoring network in terms of frequency of detection. Frequency of detection is defined as the fraction of "events" that result in a detection at either a single sampler or network of samplers. An "event" is defined as a release to the atmosphere of a specified amount of activity over a finite duration that begins on a given day and hour of the year. The methodology uses an atmospheric transport model to predict air concentrations of radionuclides at the samplers for a given release time and duration. Another metric of interest determined by the methodology is called the network intensity, which is defined as the fraction of samplers in the network that have a positive detection for a given event. The frequency of detection methodology allows for evaluation of short-term releases that include effects of short-term variability in meteorological conditions. The methodology was tested using the U.S. Department of Energy Idaho National Laboratory Site ambient air-monitoring network consisting of 37 low-volume air samplers in 31 different locations covering a 17,630 km region. Releases from six major facilities distributed over an area of 1,435 km were modeled and included three stack sources and eight ground-level sources. A Lagrangian Puff air dispersion model (CALPUFF) was used to model atmospheric transport. The model was validated using historical Sb releases and measurements. Relevant 1-wk release quantities from each emission source were calculated based on a dose of 1.9×10 mSv at a public receptor (0.01 mSv assuming release persists over a year). Important radionuclides were Am, Cs, Pu, Pu, Sr, and tritium. Results show the detection frequency was over 97.5% for the entire network considering all sources and radionuclides. Network intensity results ranged from 3.75% to 62.7%. Evaluation of individual samplers indicated some samplers were poorly located and added little to the overall

  3. Ca2+ is involved in muscarine-acetylcholine-receptor-mediated acetylcholine signal transduction in guard cells of Vicia faba L.

    MENG Fanxia; MIAO Long; ZHANG Shuqiu; LOU Chenghou

    2004-01-01

    Acetylcholine (ACh) is an important neurochemical transmitter in animals; it also exists in plants and plays a significant role in various kinds of physiological functions in plants. ACh has been known to induce the stomatal opening. By monitoring the changes of cytosolic Ca2+ with fluorescent probe Fluo-3 AM under the confocal microscopy,we found that exogenous ACh increased cytosolic Ca2+ concentration of guard cells of Vicia faba L. Muscarine, an agonist of muscarine acetylcholine receptor (mAChR), could do so as well. In contrast, atropine, the antagonist of mAChR abolished the ability of ACh to increase Ca2+ in guard cells.This mechanism is similar to mAChR in animals. When EGTA was used to chelate Ca2+ or ruthenium red to block Ca2+ released from vacuole respectively, the results showed that the increased cytosolic Ca2+ mainly come from intracellular Ca2+ store. The evidence supports that Ca2+ is involved in guard-cell response to ACh and that Ca2+ signal is coupled to mAChRs in ACh signal transduction in guard cells.

  4. Mapping of the acetylcholine binding site of the nicotinic acetylcholine receptor: [3H]nicotine as an agonist photoaffinity label

    The agonist [3H]nicotine was used as a photoaffinity label for the acetylcholine binding sties on the Torpedo nicotinic acetylcholine receptor (AChR). [3H]Nicotine binds at equilibrium with Keq = 0.6 μM to the agonist binding sites. Irradiation with 254-nm light of AChR-rich membranes equilibrated with [3H]nicotine resulted in covalent incorporation into the α- and γ-subunits, which was inhibited by agonists and competitive antagonists but not by noncompetitive antagonists. Inhibition of labeling by d-tubocurarine demonstrated that the α-subunit was labeled via both agonist sites but the γ-subunit was labeled only via the site that binds d-tubocurarine with high affinity. Chymotryptic digestion of the α-subunit confirmed that Try-198 was the principal amino acid labeled by [3H]nicotine. This confirmation required a novel radiosequencing strategy employing o-phthalaldehyde [3H]Nicotine, which is the first photoaffinity agonist used, labels primarily Tyr-198 in contrast to competitive antagonist affinity labels, which label primarily Tyr-190 and Cys-192/Cys-193

  5. Conceptual design and development of GEM based detecting system for tomographic tungsten focused transport monitoring

    Chernyshova, M.; Czarski, T.; Malinowski, K.; Kowalska-Strzęciwilk, E.; Poźniak, K.; Kasprowicz, G.; Zabołotny, W.; Wojeński, A.; Kolasiński, P.; Mazon, D.; Malard, P.

    2015-10-01

    Implementing tungsten as a plasma facing material in ITER and future fusion reactors will require effective monitoring of not just its level in the plasma but also its distribution. That can be successfully achieved using detectors based on Gas Electron Multiplier (GEM) technology. This work presents the conceptual design of the detecting unit for poloidal tomography to be tested at the WEST project tokamak. The current stage of the development is discussed covering aspects which include detector's spatial dimensions, gas mixtures, window materials and arrangements inside and outside the tokamak ports, details of detector's structure itself and details of the detecting module electronics. It is expected that the detecting unit under development, when implemented, will add to the safe operation of tokamak bringing the creation of sustainable nuclear fusion reactors a step closer. A shorter version of this contribution is due to be published in PoS at: 1st EPS conference on Plasma Diagnostics

  6. Conceptual design and development of GEM based detecting system for tomographic tungsten focused transport monitoring

    Implementing tungsten as a plasma facing material in ITER and future fusion reactors will require effective monitoring of not just its level in the plasma but also its distribution. That can be successfully achieved using detectors based on Gas Electron Multiplier (GEM) technology. This work presents the conceptual design of the detecting unit for poloidal tomography to be tested at the WEST project tokamak. The current stage of the development is discussed covering aspects which include detector's spatial dimensions, gas mixtures, window materials and arrangements inside and outside the tokamak ports, details of detector's structure itself and details of the detecting module electronics. It is expected that the detecting unit under development, when implemented, will add to the safe operation of tokamak bringing the creation of sustainable nuclear fusion reactors a step closer. A shorter version of this contribution is due to be published in PoS at: 1st EPS conference on Plasma Diagnostics

  7. Transcriptomic effects of depleted uranium on acetylcholine and cholesterol metabolisms in Alzheimer's disease model; Effets transcriptomiques de l'uranium appauvri sur les metabolismes de l'acetylcholine et du cholesterol chez un modele de maladie d'Alzheimer

    Lestaevel, Ph.; Bensoussan, H.; Racine, R.; Airault, F.; Gourmelon, P.; Souidi, M. [Direction de la radioprotection de l' Homme, service de radiobiologie et d' epidemiologie, laboratoire de radiotoxicologie experimentale, institut de radioprotection et de surete nucleaire, BP no 17, 92262 Fontenay-aux-Roses cedex (France)

    2011-02-15

    Some heavy metals, or aluminium, could participate in the development of Alzheimer disease (AD). Depleted uranium (DU), another heavy metal, modulates the cholinergic system and the cholesterol metabolism in the brain of rats, but without neurological disorders. The aim of this study was to determine what happens in organisms exposed to DU that will/are developing the AD. This study was thus performed on a transgenic mouse model for human amyloid precursor protein (APP), the Tg2576 strain. The possible effects of DU through drinking water (20 mg/L) over an 8-month period were analyzed on acetylcholine and cholesterol metabolisms at gene level in the cerebral cortex. The mRNA levels of choline acetyl transferase (ChAT) vesicular acetylcholine transporter (VAChT) and ATP-binding cassette transporter A1 (ABC A1) decreased in control Tg2576 mice in comparison with wild-type mice (respectively -89%, -86% and -44%, p < 0.05). Chronic exposure of Tg2576 mice to DU increased mRNA levels of ChAT (+189%, p < 0.05), VAChT (+120%, p < 0.05) and ABC A1 (+52%, p < 0.05) compared to control Tg2576 mice. Overall, these modifications of acetylcholine and cholesterol metabolisms did not lead to increased disturbances that are specific of AD, suggesting that chronic DU exposure did not worsen the pathology in this experimental model. (authors)

  8. Colloidal transport of uranium in soil: Size fractionation and characterization by field-flow fractionation-multi-detection

    The aim of this study was to characterize colloids associated with uranium by using an on-line fractionation/multi-detection technique based on asymmetrical flow field-flow fractionation (As-Fl-FFF) hyphenated with UV detector, multi angle laser light scattering (MALLS) and inductively coupling plasma-mass spectrometry (ICP-MS). Moreover, thanks to the As-Fl-FFF, the different colloidal fractions were collected and characterized by a total organic carbon analyzer (TOC). Thus it is possible to determine the nature (organic or inorganic colloids), molar mass, size (gyration and hydrodynamic radii) and quantitative uranium distribution over the whole colloidal phase. In the case of the site studied, two populations are highlighted. The first population corresponds to humic-like substances with a molar mass of (1500 ± 300) g mol-1 and a hydrodynamic diameter of (2. 0 ± 0. 2) nm. The second one has been identified as a mix of carbonated nano-particles or clays with organic particles (aggregates and/or coating of the inorganic particles) with a size range hydrodynamic diameter between 30 and 450 nm. Each population is implied in the colloidal transport of uranium: maximum 1% of the uranium content in soil leachate is transported by the colloids in the site studied, according to the depth in the soil. Indeed, humic substances are the main responsible of this transport in sub-surface conditions whereas nano-particles drive the phenomenon in depth conditions. (authors)

  9. Detection and correction of blinking bias in image correlation transport measurements of quantum dot tagged macromolecules

    Durisic, Nela; Bachir, Alexia I; Kolin, David L; Hebert, Benedict; Lagerholm, B Christoffer; Grutter, Peter; Wiseman, Paul W

    2007-01-01

    model, but the transport coefficients can have significant systematic errors in the measurements due to blinking. Image correlation measurements of the diffusing QD samples measured at different laser excitation powers and analysis of computer simulated image time series verified that the effect we...... application of the image correlation methods for measurement of the diffusion coefficient of glycosyl phosphatidylinositol-anchored proteins tagged with QDs as imaged on living fibroblasts Udgivelsesdato: 2007-Aug-15......Semiconductor nanocrystals or quantum dots (QDs) are becoming widely used as fluorescent labels for biological applications. Here we demonstrate that fluorescence fluctuation analysis of their diffusional mobility using temporal image correlation spectroscopy is highly susceptible to systematic...

  10. Online Slug Detection in Multi-phase Transportation Pipelines Using Electrical Tomography

    Pedersen, Simon; Mai, Christian; Hansen, Leif;

    2015-01-01

    Slugging flow in offshore oil & gas multi-phase transportation pipelines cause big challenges as the flow regime induces flow and pressure oscillations in the multi-phase pipelines. The negative impacts of the most severe slugs are significant and thus the elimination of slugging flow in the......) has been examined as an alternative to the traditional pressure transmitters. A lab-scaled testing facility has been constructed in order to obtain test data from a ERT transmitter with 12 probes. Different flow regimes have been generated by a pump and a compressor where 2-phase flow can be tested...

  11. Detection of smuggling of nuclear material covered by a legal transport of radioactive material

    Feasibility study was performed in order to investigate the possible on site measurement techniques and approaches applicable in cases when a legal transport of radioactive material is used to cover the radiation of the smuggled uranium. The study was concentrating on non-destructive, passive gamma-spectrometric methods. Possible application of NaI, CdZnTe, and high purity Germanium planar detectors was investigated. An important conclusion of the study was that the higher resolution of the measured spectra provides significant advantages. (author)

  12. A robust method for inverse transport modelling of atmospheric emissions using blind outlier detection

    M. Martinez-Camara

    2014-05-01

    Full Text Available Emissions of harmful substances into the atmosphere are a serious environmental concern. In order to understand and predict their effects, it is necessary to estimate the exact quantity and timing of the emissions, from sensor measurements taken at different locations. There exists a number of methods for solving this problem. However, these existing methods assume Gaussian additive errors, making them extremely sensitive to outlier measurements. We first show that the errors in real-world measurement datasets come from a heavy-tailed distribution, i.e., include outliers. Hence, we propose to robustify the existing inverse methods by adding a blind outlier detection algorithm. The improved performance of our method is demonstrated on a real dataset and compared to previously proposed methods. For the blind outlier detection, we first use an existing algorithm, RANSAC, and then propose a modification called TRANSAC, which provides a further performance improvement.

  13. Effects of cholinoblockers on acetylcholine content in rat striatum in neuroleptic-induced parkinsonism.

    Dagaev, S G; Kosmachev, A B; Soloveva, N E; Filko, O A; Sanotskii, V I; Dolgo-Saburov, V B

    2004-02-01

    Correction of neuroleptic-induced parkinsonism in rats with two central cholinoblockers atropine and pentifine (acetylene aminoalcohol synthesized at Institute of Toxicology) were studied by measuring the content of acetylcholine in the striatum. The content of the transmitter secretion was estimated from the content of bound acetylcholine fraction in homogenates of the above-mentioned compartment of the brain. The results indicate that atropine and pentifine in doses equally effectively preventing catalepsy in rats had different effects on acetylcholine secretion in the striatum. Hence, cholinolytics with different pharmacological selective effects differently interact with central muscarine receptor subtypes. PMID:15273765

  14. Second Harmonic Detection of Spin-Dependent Transport in Magnetic Nanostructures

    Yu, Hai-Ming; Granville, S.; Yu, Da-Peng; J-ph., Ansermet

    2010-02-01

    Detection of the second harmonic response of magnetic nanostructures to an ac current is shown to be a very sensitive probe of the magnetization reversal process. A temperature oscillation is obtained by Joule heating instead of using a laser as the heat source, as in thermo-galvanic voltage measurements (TGV). Joule heating is used to produce a large local temperature gradient in asymmetric Co/Cu/Co spin valves. Evidence is found for an effect of a heat current on magnetization.

  15. Comparison of the Ability of Various Imaging Modalities (CT & Plain X- Ray in Detecting Drug Transport in Body Packers

    Morteza Sanei

    2009-01-01

    Full Text Available "ndrugs within the human body. In our country due to vast common border with Afghanistan which is the biggest Opium producer in the world and has the second place in Heroine production, drug smuggling has potential national threat and besides it has a global impact as using our territory as the major smuggling route to the west. Furthermore, in recent years new generations of African smugglers of new types of drugs are using our country as a transit route to transport drugs to Europe or Africa. In this way handmade or automatically produced packets are swallowed, rectally or vaginally inserted, and then transported. The first choice modality is plain x-ray of the abdomen in upright and supine positions. Recently abdominal and pelvic CT without contrast has shown a great success rate in the detection of body packers with changing window modality to detect different types of drugs. "nMaterials and Methods: Plain x-ray and abdominal and pelvic CT without contrast were performed for 12 cases who confessed to drug packet ingestion. The presence, number and location of the packets were evaluated in different modalities and the density of the packets were also measured in Hounsfield units (HU. "nResults: The mean age of our cases was 28.2±5.9 years (range, 17-35 years. Eleven (91.6 % patients were male and only one case was female. All patients had characteristic findings in plain x-ray and also all packets were visualized in all patients "nConclusion: Plain x-ray has a distinctive position in detecting packets in intestines especially when oral contrast materials are used. It is cheaper and more accessible than CT, but using different Hounsfield units in CT windows can even characterize different types of drugs even before extracting them.  

  16. Alteration in cellular acetylcholine influences dauer formation in Caenorhabditis elegans.

    Lee, Jeeyong; Kim, Kwang-Youl; Paik, Young-Ki

    2014-02-01

    Altered acetylcholine (Ach) homeostasis is associated with loss of viability in flies, developmental defects in mice, and cognitive deficits in human. Here, we assessed the importance of Ach in Caenorhabditis elegans development, focusing on the role of Ach during dauer formation. We found that dauer formation was disturbed in choline acetyltransferase (cha-1) and acetylcholinesterase (ace) mutants defective in Ach biosynthesis and degradation, respectively. When examined the potential role of G-proteins in dauer formation, goa-1 and egl-30 mutant worms, expressing mutated versions of mammalian G(o) and G(q) homolog, respectively, showed some abnormalities in dauer formation. Using quantitative mass spectrometry, we also found that dauer larvae had lower Ach content than did reproductively grown larvae. In addition, a proteomic analysis of acetylcholinesterase mutant worms, which have excessive levels of Ach, showed differential expression of metabolic genes. Collectively, these results indicate that alterations in Ach release may influence dauer formation in C. elegans. PMID:24219868

  17. Valence of acetylcholine-receptor-antibody-titers in myasthenia gravis

    In a retrospective study in 47 patients with myasthenia gravis acetylcholine-receptor-antibody-titers (AChR-AB) were correlated with the severity of the disease. In 18 patients the course of titers was studied and two groups of patients could be differentiated: patients with relative constant and patients with fluctuating titers. Age, age of begin of myasthenia and sex did not influence the titers. Also the duration of the disease and the severity of symptoms did not influence the level of AChR-AB-titers. In this retrospective study the influence of immunsuppressive therapy on the intra-individual course of AB-titers and their correlation with the clinical symptoms could not be judged. Measurement of AChR-AB is of value for the diagnosis of myasthenia gravis and important for judging the clinical course and the effect of therapy. (Author)

  18. Structure and superorganization of acetylcholine receptor–rapsyn complexes

    Zuber, Benoît; Unwin, Nigel

    2013-01-01

    The scaffolding protein at the neuromuscular junction, rapsyn, enables clustering of nicotinic acetylcholine receptors in high concentration and is critical for muscle function. Patients with insufficient receptor clustering suffer from muscle weakness. However, the detailed organization of the receptor–rapsyn network is poorly understood: it is unclear whether rapsyn first forms a wide meshwork to which receptors can subsequently dock or whether it only forms short bridges linking receptors together to make a large cluster. Furthermore, the number of rapsyn-binding sites per receptor (a heteropentamer) has been controversial. Here, we show by cryoelectron tomography and subtomogram averaging of Torpedo postsynaptic membrane that receptors are connected by up to three rapsyn bridges, the minimum number required to form a 2D network. Half of the receptors belong to rapsyn-connected groups comprising between two and fourteen receptors. Our results provide a structural basis for explaining the stability and low diffusion of receptors within clusters. PMID:23754381

  19. Applicability of gamma detection systems for the detection of illicit transports of radioactive substances in cargo containers shielded by the cargo

    measurement conditions on frequently occurring radioactive substances and on minimal detectable activities. The second part is a simulation of portal monitors for gamma radiation. This is done to simulate gamma spectra of radionuclides inside cargo containers transported through a portal monitor. Measurements: Measurements were conducted at the cargo container checkpoint of the German Customs Office at the Hamburg Harbor. At this checkpoint a radiation portal monitor (RTM 910, produced by Mirion Technologies) has been installed. The RTM 910 is capable of neutron and gamma detection with a low energy-resolution. To detect the gamma radiation plastic scintillators are used. The RTM 910 has detectors on both sides of an incoming street to the checkpoint. The distance between the two detector parts is six meters and the cargo containers are transported through this portal monitor with an average velocity of 30 km/h. In the field experiment 30 to 40 cargo containers were controlled per hour. In this time approximately three alarms per hour were given. To examine what kind of radionuclides caused these alarms, it was necessary to analyze spectra of the radiation when such an alarm occurred. For the identification of the radioactive substances two other gamma detectors were used in addition to the RTM 910. One detector (ReGeM, produced by Canberra) was a high-purity-germanium detector with an energy resolution of less than 2 keV (e.g. 0,3% at 662 keV). The other detector (Spir Ident, produced by Mirion Technologies) is based on sodium-iodide and has an energy resolution of about 10 keV. The idea was to take spectra exactly at the time an alarm was given by the RTM 910 and to identify the alarm causing radionuclides by analyzing the spectra. It was possible to identify radionuclides in the spectra that were simultaneously recorded to RTM 910 alarms. All the detected radionuclides are naturally occurring. Simulations: In order to estimate the physical limitations and the remaining

  20. The mechanism of acetylcholine receptor in binding MuSK in myasthenia gravis and the role of HSP90 molecular chaperone

    Chen, Rongbo; Chen, Siqia; Liao, Juan; Chen, Xiaopu; Xu, Xiaoling

    2016-01-01

    As an autoimmune disease, myasthenia gravis is caused by the dysfunction of neural transmission. Acetylcholine is known to exert its function after entering into synaptic cleft through binding onto postsynaptic membrane. The role of acetylcholine in binding MuSK in myasthenia gravis, however, remains unknown. A total of 38 myasthenia gravis patients and 27 healthy controls were included in this study for the detection of the expression of MuSK using immunofluorescent method. Expression of both MuSK and interleukin-6 (IL-6) were measured by Western blot, followed by the correlation analysis between heat shock protein 90 (HSP90) and IL-6 which were measured by enzyme-linked immunosorbent assay (ELISA). In myasthenia gravis patients, MuSK was co-localized with acetylcholine at the postsynaptic membrane. Such accumulation of MuSK, however, did not occur in normal people. Meanwhile we also observed elevated expression of IL-6 in myasthenia gravis patients (pmyasthenia gravis patients, with elevated expression. HSP90 in disease people can activate IL-6 mediated signaling pathways. PMID:27186300

  1. Incrustations detection system for petroleum transport pipes based on gamma transmission

    The scale formed over the inner walls of the ducts conveying the extracted product from offshore oil wheels is a major cause of losses to companies and in some cases even the safety is affected. The consequence of such fouling is the duct's square section reduction that causes extraction flow decrease and can also cause an increase in pressure inside the wheel, with serious consequences for safety. The objective of this work is to propose a mobile inspection system, which can be transported by underwater robots to inspect the lines of ducts in the outputs of the oil wheels. The measurement method to be adopted will be the gamma rays' beam attenuation at a predetermined position of the pipe. This transmission value compared to a clear pipe reading will show if the thickness of the inlay is larger or smaller than an assumed thickness. To carry out the measurements it was designed and built an electronic system comprising power supply, amplifier, single channel analyzer and a counter timer that was connected to a CsI scintillator detector coupled to a PIN photodiode. The system was set up to perform measurements with constant accuracy of ±1%. Tests during the study demonstrated the effectiveness of the proposed method with the obtained results with a carbon steel duct section of 270 mm diameter, removed from the field, with asymmetric BaSO4 inlay. (author)

  2. Inhibition by substance P of some peripheral actions of acetylcholine in the cat

    Clark, S.L.; Ryall, R. W.

    1982-01-01

    1 The effect of substance P on contractions of the nictitating membrane and pressor responses to acetylcholine (ACh) and dimethylphenyl-piperazinium (DMPP) which were mediated via nocotinic receptors was studied in cats anaesthetized with chloralose.

  3. A family of acetylcholine-gated chloride channel subunits in Caenorhabditis elegans.

    Putrenko, Igor; Zakikhani, Mahvash; Dent, Joseph A

    2005-02-25

    The genome of the nematode Caenorhabditis elegans encodes a surprisingly large and diverse superfamily of genes encoding Cys loop ligand-gated ion channels. Here we report the first cloning, expression, and pharmacological characterization of members of a family of anion-selective acetylcholine receptor subunits. Two subunits, ACC-1 and ACC-2, form homomeric channels for which acetylcholine and arecoline, but not nicotine, are efficient agonists. These channels are blocked by d-tubocurarine but not by alpha-bungarotoxin. We provide evidence that two additional subunits, ACC-3 and ACC-4, interact with ACC-1 and ACC-2. The acetylcholine-binding domain of these channels appears to have diverged substantially from the acetylcholine-binding domain of nicotinic receptors. PMID:15579462

  4. Notexin preferentially inhibits the release of newly synthesized acetylcholine from rat brain synaptosomal fractions

    An investigation was made of the effects of the snake venom neurotoxin, notexin, on acetylcholine turnover in rat brain P2 fractions using a gas chromatographic mass spectrometric assay for acetylcholine and choline. In contrast to earlier reports, we found a stimulation of the uptake and acetylation of labeled choline by toxin-treated P2 fractions. More significantly, notexin inhibited the release of this newly synthesized transmitter. These effects were found to be dependent on the dose of the toxin and the time of exposure of the P2 fraction to notexin. Longer exposure to notexin or experiments involving resuspension of notexin-treated P2 fractions appeared to result in considerable lysis of the transmitter-containing particles. Thus, notexin may alter acetylcholine compartmentation in the nerve ending and thereby affect acetylcholine synthesis

  5. Electrolyte and protein secretion by the perfused rabbit mandibular gland stimulated with acetylcholine or catecholamines

    Case, R M; Conigrave, A D; Novak, I;

    1980-01-01

    1. A method is described for the isolation and vascular perfusion in vitro of the mandibular gland of the rabbit. The perfusate is a physiological salt solution containing glucose as the only metabolic substrate.2. During perfusion with solutions containing acetylcholine, the gland secretes......) concentrations and the osmolality of acetylcholine evoked saliva exhibited flow-dependency similar to that seen in vivo. The concentrations of Na and Cl, but not K and HCO(3), increased by about 25 mmol l(-1) during periods of prolonged stimulation with acetylcholine even though the salivary secretory rate was...... composition of isoproterenol-evoked saliva was vastly different from that evoked by acetylcholine, being particularly rich in K and HCO(3). The isoproterenol-evoked saliva was also extremely rich in protein so that the total protein secretion evoked by isoproterenol was much greater than that evoked by...

  6. Effect of spontaneous diffusion in micro/nanoporous chemically crosslinked poly (N-vinyl imidazole) gel on the conformational changes of acetylcholine

    Vaganova, Evgenia; Pierola, Ines F.; Ovadia, Haim; Lyshevski, Sergey E.; Yitzchaik, Shlomo

    2009-02-01

    Interdependent structural properties such as molecular conformation, flexibility and charge redistribution control the intermolecular interactions of acetylcholine (ACh) with adjacent molecules. This paper reports the results of an investigation of the effect of the diffusion of ACh through a nano/microporous poly (N-vinylimidazole) (PVI) gel on its structural properties, namely on changes in its conformation. To investigate the conformational changes of ACh during spontaneous diffusion through the gel, the fluorescence lifetime of the label molecule - fluorescein - was monitored. To clarify the results, analogous experiments were conducted with nicotinic acid and dopamine. In contrast to the nicotinic acid and dopamine, ACh can play the role of a regulator in molecular transport.

  7. NA22 Model Cities Project - LL244T An Intelligent Transportation System-Based Radiation Alert and Detection System

    Peglow, S

    2004-02-24

    The purpose of this project was twofold: first, provide an understanding of the technical foundation and planning required for deployment of Intelligent Transportation System (ITS)-based system architectures for the protection of New York City from a terrorist attack using a vehicle-deployed nuclear device; second, work with stakeholders to develop mutual understanding of the technologies and tactics required for threat detection/identification and establish guidelines for designing operational systems and procedures. During the course of this project we interviewed and coordinated analysis with people from the New Jersey State Attorney General's office, the New Jersey State Police, the Port Authority of New York/New Jersey, the Counterterrorism Division of the New York City Police Department, the New Jersey Transit Authority, the State of New Jersey Department of Transportation, TRANSCOM and a number of contractors involved with state and federal intelligent transportation development and implementation. The basic system architecture is shown in the figure below. In an actual system deployment, radiation sensors would be co-located with existing ITS elements and the data will be sent to the Traffic Operations Center. A key element of successful system operation is the integration of vehicle data, such as license plate, EZ pass ID, vehicle type/color and radiation signature. A threat data base can also be implemented and utilized in cases where there is a suspect vehicle identified from other intelligence sources or a mobile detector system. Another key aspect of an operational architecture is the procedures used to verify the threat and plan interdiction. This was a major focus of our work and discussed later in detail. In support of the operational analysis, we developed a detailed traffic simulation model that is described extensively in the body of the report.

  8. Effects of the α subunit on imidacloprid sensitivity of recombinant nicotinic acetylcholine receptors

    Matsuda, K; Buckingham, S D; Freeman, J.C.; Squire, M D; Baylis, H. A.; Sattelle, D B

    1998-01-01

    Imidacloprid is a new insecticide with selective toxicity for insects over vertebrates. Recombinant (α4β2) chicken neuronal nicotinic acetylcholine receptors (AChRs) and a hybrid nicotinic AChR formed by co-expression of a Drosophila melanogaster neuronal α subunit (SAD) with the chicken β2 subunit were heterologously expressed in Xenopus oocytes by nuclear injection of cDNAs. The agonist actions of imidacloprid and other nicotinic AChR ligands ((+)-epibatidine, (−)-nicotine and acetylcholine...

  9. Expression of the α7 nicotinic acetylcholine receptor in human lung cells

    Schuller Hildegard M; Dhar Madhu; Plummer Howard K

    2005-01-01

    Abstract Background We and others have shown that one of the mechanisms of growth regulation of small cell lung cancer cell lines and cultured pulmonary neuroendocrine cells is by the binding of agonists to the α7 neuronal nicotinic acetylcholine receptor. In addition, we have shown that the nicotine-derived carcinogenic nitrosamine, 4(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), is a high affinity agonist for the α7 nicotinic acetylcholine receptor. In the present study, our goal was t...

  10. Two types of muscarinic acetylcholine receptors in Drosophila and other arthropods

    Collin, Caitlin Alexis; Hauser, Frank; Gonzalez de Valdivia, Ernesto I; Li, Shizhong; Reisenberger, Julia; Carlsen, Eva M.M.; Khan, Zaid; Hansen, Niels Ø.; Puhm, Florian; Søndergaard, Leif; Niemiec, Justyna; Heninger, Magdalena; Ren, Guilin Robin; Grimmelikhuijzen, Cornelis

    2013-01-01

    Muscarinic acetylcholine receptors (mAChRs) play a central role in the mammalian nervous system. These receptors are G protein-coupled receptors (GPCRs), which are activated by the agonists acetylcholine and muscarine, and blocked by a variety of antagonists. Mammals have five mAChRs (m1-m5). In ...... (Hydra), had two A-type mAChRs. From these data we propose a model for the evolution of mAChRs....

  11. Fusion of waveform events and radionuclide detections with the help of atmospheric transport modelling

    Krysta, Monika; Kushida, Noriyuki; Kotselko, Yuriy; Carter, Jerry

    2016-04-01

    Possibilities of associating information from four pillars constituting CTBT monitoring and verification regime, namely seismic, infrasound, hydracoustic and radionuclide networks, have been explored by the International Data Centre (IDC) of the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) for a long time. Based on a concept of overlying waveform events with the geographical regions constituting possible sources of the detected radionuclides, interactive and non-interactive tools were built in the past. Based on the same concept, a design of a prototype of a Fused Event Bulletin was proposed recently. One of the key design elements of the proposed approach is the ability to access fusion results from either the radionuclide or from the waveform technologies products, which are available on different time scales and through various different automatic and interactive products. To accommodate various time scales a dynamic product evolving while the results of the different technologies are being processed and compiled is envisioned. The product would be available through the Secure Web Portal (SWP). In this presentation we describe implementation of the data fusion functionality in the test framework of the SWP. In addition, we address possible refinements to the already implemented concepts.

  12. Novel aspects of cholinergic regulation of colonic ion transport.

    Bader, Sandra; Diener, Martin

    2015-06-01

    Nicotinic receptors are not only expressed by excitable tissues, but have been identified in various epithelia. One aim of this study was to investigate the expression of nicotinic receptors and their involvement in the regulation of ion transport across colonic epithelium. Ussing chamber experiments with putative nicotinic agonists and antagonists were performed at rat colon combined with reverse transcription polymerase chain reaction (RT-PCR) detection of nicotinic receptor subunits within the epithelium. Dimethylphenylpiperazinium (DMPP) and nicotine induced a tetrodotoxin-resistant anion secretion leading to an increase in short-circuit current (I sc) across colonic mucosa. The response was suppressed by the nicotinic receptor antagonist hexamethonium. RT-PCR experiments revealed the expression of α2, α4, α5, α6, α7, α10, and β4 nicotinic receptor subunits in colonic epithelium. Choline, the product of acetylcholine hydrolysis, is known for its affinity to several nicotinic receptor subtypes. As a strong acetylcholinesterase activity was found in colonic epithelium, the effect of choline on I sc was examined. Choline induced a concentration-dependent, tetrodotoxin-resistant chloride secretion which was, however, resistant against hexamethonium, but was inhibited by atropine. Experiments with inhibitors of muscarinic M1 and M3 receptors revealed that choline-evoked secretion was mainly due to a stimulation of epithelial M3 receptors. Although choline proved to be only a partial agonist, it concentration-dependently desensitized the response to acetylcholine, suggesting that it might act as a modulator of cholinergically induced anion secretion. Thus the cholinergic regulation of colonic ion transport - up to now solely explained by cholinergic submucosal neurons stimulating epithelial muscarinic receptors - is more complex than previously assumed. PMID:26236483

  13. Necessities detected in patients derived to sanitary center in an ambulance of the urgent transport network after being treated by the 061 emergency team

    Sixto Cámara Anguita; Antonio J. Valenzuela Rodríguez

    2007-01-01

    The integral systems of urgencies and sanitary emergencies has, as resources for the urgent transport of patients, with nonwelfare ambulances, ambulances of basic life support and ambulances of advanced life support. In the two first, due to the ambiguity of the norm, the presence of a nurse to give care is not compulsory. Nevertheless, in the present study, it is detected that, the patients of this study, transferred in nonwelfare ambulance of the urgent transport network to a useful hospita...

  14. Characterization of the charge-carrier transport properties of IIa-Tech SC diamond for radiation detection applications

    Single crystal (SC) diamond has since years demonstrated its interest for the fabrication of radiation detectors, especially where the material properties are providing superior interests with respect to the detection application. Among the industrial suppliers able to provide on a commercial basis high-grade single crystal diamond, IIa-Tech has recently appeared in the market as a new player. The aim of this paper is to assess the quality of one SC sample when characterized under α-particles for the measurement of its carrier transport properties. We observed that full charge collection could be observed at biases as low as 0.11 V/μm with no space charge build-up (conventionally typical bias values used are closer to 1 V/μm). Velocity reached values of 38 μm/ns and 53 μm/ns for electrons and holes, respectively (values probed at 0.33 V/μm). Similarly, the α detection spectrum displays a sharp line demonstrating the good uniformity of the material over its surface. By combining the measurements with more conventional optical observations such as birefringence and cathodoluminescence spectroscopy, it comes that the material demonstrates its ability to be used as a detector, with properties that can compare with the highest grade materials today available on the market. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  15. Boosting visual cortex function and plasticity with acetylcholine to enhance visual perception

    Jun-Il eKang

    2014-09-01

    Full Text Available The cholinergic system is a potent neuromodulatory system that plays critical roles in cortical plasticity, attention and learning. In this review, we propose that the cellular effects of acetylcholine in the primary visual cortex during the processing of visual inputs might induce perceptual learning; i.e., long-term changes in visual perception. Specifically, the pairing of cholinergic activation with visual stimulation increases the signal-to-noise ratio, cue detection ability and long-term facilitation in the primary visual cortex. This cholinergic enhancement would increasesthe strength of thalamocortical afferents to facilitate the treatment of a novel stimulus while decreasing the cortico-cortical signaling to reduce recurrent or top-down modulation. This balance would be mediated by different cholinergic receptor subtypes that are located on both glutamatergic and GABAergic neurons of the different cortical layers. The mechanisms of cholinergic enhancement are closely linked to attentional processes, long-term potentiation and modulation of the excitatory/inhibitory balance. Recently, it was found that boosting this system during visual training robustly enhances sensory perception in a long-term manner. Our hypothesis is that repetitive pairing of cholinergic and sensory stimulation over a long period of time induces long-term changes in the processing of trained stimuli that might improve perceptual ability. Various non-invasive approaches to the activation of the cholinergic neurons have strong potential to improve visual perception.

  16. Binding affinities of anti-acetylcholine receptor autoantibodies in myasthenia gravis

    Antibodies directed against acetylcholine (ACh) receptors are present in the sera of nearly 90% of patients with myasthenia gravis (MG), and are involved in the pathogenesis of this autoimmune disease. However, the antibody titers measured by the standard radioimmunoassay correspond poorly with the clinical severity of the disease. To determine whether this disparity could be accounted for by differences in the binding affinities of anti-ACh receptor antibodies in different patients, we have measured the binding affinities of these autoantibodies in 15 sera from MG patients. The affinity constants (K/sub o/), as determined by Scatchard analysis, were all in the range of 1010 M-1, comparable to the highest values reported in immunized animals. The affinity constants were truly representative of the population of autoantibodies detected by the radioimmunoassay, as shown by the remarkable linearity of the Scatchard plots (r2>0.90) and the close correlation between the antibody titers determined by extrapolation of the Scatchard plots and by saturation analysis (r = 0.99; p < 0.001). There was only a 6-fold variation in affinity constants measured in this series of patients despite widely differing antibody titers and severity of the disease. Factors other than the titer and affinity of anti-ACh receptor antibodies may correlate better with the clinical manifestations of MG

  17. Binding affinities of anti-acetylcholine receptor autoantibodies in myasthenia gravis

    Bray, J.J.; Drachman, D.B.

    1982-01-01

    Antibodies directed against acetylcholine (ACh) receptors are present in the sera of nearly 90% of patients with myasthenia gravis (MG), and are involved in the pathogenesis of this autoimmune disease. However, the antibody titers measured by the standard radioimmunoassay correspond poorly with the clinical severity of the disease. To determine whether this disparity could be accounted for by differences in the binding affinities of anti-ACh receptor antibodies in different patients, we have measured the binding affinities of these autoantibodies in 15 sera from MG patients. The affinity constants (K/sub o/), as determined by Scatchard analysis, were all in the range of 10/sup 10/ M/sup -1/, comparable to the highest values reported in immunized animals. The affinity constants were truly representative of the population of autoantibodies detected by the radioimmunoassay, as shown by the remarkable linearity of the Scatchard plots (r/sup 2/>0.90) and the close correlation between the antibody titers determined by extrapolation of the Scatchard plots and by saturation analysis (r = 0.99; p < 0.001). There was only a 6-fold variation in affinity constants measured in this series of patients despite widely differing antibody titers and severity of the disease. Factors other than the titer and affinity of anti-ACh receptor antibodies may correlate better with the clinical manifestations of MG.

  18. A radioimmunoassay for the quantitative evaluation of anti-human acetylcholine receptor antibodies in myasthenia gravis

    A radioimmunoassay was developed for the quantitative evaluation of antibodies to the acetylcholine receptor in the serum of myasthenic patients. AcChR was extracted from human muscle. A detailed preparation of the 125I-labelled α-Bgt-AcChR complex used as antigen is reported. Usually, an average of 20 pmol were obtained from 100 g muscle. This preparation is stable for 1 month in presence of an inhibitor of proteolysis and sufficient for performing about fifteen assays. The labelled complex was incubated with increasing amounts of sera and precipitated with anti-human IgG serum. Titres were expressed in pmol 125I-labelled α-Bgt-AcChR complex precipitated per ml serum. Out of thirty-nine sera tested thirty-six had positive titres ranging from 0.1 to 46 pmol/ml. No anti-AcChR were detected in the sera from twenty-seven patients used as controls. (author)

  19. Molecular alteration of a muscarinic acetylcholine receptor system during synaptogenesis

    Biochemical properties of the muscarinic acetylcholine receptor system of the avian retina were found to change during the period when synapses form in ovo. Comparison of ligand binding to membranes obtained before and after synaptogenesis showed a significant increase in the affinity, but not proportion, of the high affinity agonist-binding state. There was no change in receptor sensitivity to antagonists during this period. Pirenzepine binding, which can discriminate muscarinic receptor subtypes, showed the presence of a single population of low affinity sites (M2) before and after synaptogenesis. The change in agonist binding was not due to the late development of receptor function. However, detergent-solubilization of membranes eliminated differences in agonist binding between receptors from embryos and hatched chicks, suggesting a developmental change in interactions of the receptor with functionally related membrane components. A possible basis for altered interactions was obtained from isoelectric point data showing that the muscarinic receptor population underwent a transition from a predominantly low pI form (4.25) in 13 day embryos to a predominantly high pI form (4.50) in newly hatched chicks. The possibility that biochemical changes in the muscarinic receptor play a role in differentiation of the system by controlling receptor position on the surface of nerve cells is discussed

  20. Increased expression of the nicotinic acetylcholine receptor in stimulated muscle.

    O'Reilly, Clare; Pette, Dirk; Ohlendieck, Kay

    2003-01-10

    Chronic low-frequency stimulation has been used as a model for investigating responses of skeletal muscle fibres to enhanced neuromuscular activity under conditions of maximum activation. Fast-to-slow isoform shifting of markers of the sarcoplasmic reticulum and the contractile apparatus demonstrated successful fibre transitions prior to studying the effect of chronic electro-stimulation on the expression of the nicotinic acetylcholine receptor. Comparative immunoblotting revealed that the alpha- and delta-subunits of the receptor were increased in 10-78 day stimulated specimens, while an associated component of the surface utrophin-glycoprotein complex, beta-dystroglycan, was not drastically changed in stimulated fast skeletal muscle. Previous studies have shown that electro-stimulation induces degeneration of fast glycolytic fibres, trans-differentiation leading to fast-to-slow fibre transitions and activation of muscle precursor cells. In analogy, our results indicate a molecular modification of the central functional unit of the post-synaptic muscle surface within existing neuromuscular junctions and/or during remodelling of nerve-muscle contacts. PMID:12504123

  1. Effects of two oxadiazolidinones on cholinesterases and acetylcholine receptors

    Inhibition of acetylcholinesterase (AChE) and butyryl cholinesterase (BuChE) by 3-(2,3-dihydro-2,2-dimethyl-benzofuran-'7-yl)-5-methoxy-1,3,4-oxadiazol-2(3H)-one (DBOX) and 3-(2-methoxyphenyl)-5-methoxy-1,3,4-oxadiazol-2(3H)-one (MPOX) was measured by the Ellmann spectrophotometric method. Inhibition was quasi first order and irreversible. DBOX was 2-3 orders of magnitude more potent than MPOX. Housefly brain AChE and horse serum BuChE were more sensitive than AChEs of red blood cells or eel and Torpedo electric organs. It is suggested that the nonesteratic oxadiazolidinones are activated to carbanillates on the surface of the enzyme and produce a carbanillated enzyme which ages rapidly. Carbamate anticholinesterases protected AChE against carbanillation as they did against phosphorylation. At higher concentrations, the two oxadiazolidinones also affected binding of [125I] α bungarotoxin and [3H]perhydrohistrionicotoxin to Torpedo nicotinic acetylcholine receptors, but did not affect binding of [3H]quinuclidinyl benzilate to rat brain muscarinic receptors

  2. Therapeutic Potential of α7 Nicotinic Acetylcholine Receptors.

    Bertrand, Daniel; Lee, Chih-Hung L; Flood, Dorothy; Marger, Fabrice; Donnelly-Roberts, Diana

    2015-10-01

    Progress in the fields of neuroscience and molecular biology has identified the forebrain cholinergic system as being important in many higher order brain functions. Further analysis of the genes encoding the nicotinic acetylcholine receptors (nAChRs) has highlighted, in particular, the role of α7 nAChRs in these higher order brain functions as evidenced by their peculiar physiologic and pharmacological properties. As this receptor has gained the attention of scientists from academia and industry, our knowledge of its roles in various brain and bodily functions has increased immensely. We have also seen the development of small molecules that have further refined our understanding of the roles of α7 nAChRs, and these molecules have begun to be tested in clinical trials for several indications. Although a large body of data has confirmed a role of α7 nAChRs in cognition, the translation of small molecules affecting α7 nAChRs into therapeutics has to date only progressed to the stage of testing in clinical trials. Notably, however, most recent human genetic and biochemical studies are further underscoring the crucial role of α7 nAChRs and associated genes in multiple organ systems and disease states. The aim of this review is to discuss our current knowledge of α7 nAChRs and their relevance as a target in specific functional systems and disease states. PMID:26419447

  3. Alpha-conotoxins as pharmacological probes of nicotinic acetylcholine receptors

    Layla AZAM; J Michael MCINTOSH

    2009-01-01

    Cysteine-rich peptides from the venom of cone snails (Conus) target a wide variety of different ion channels. One family of conopeptides, the a-conotoxins, specifically target different isoforms of nicotinic acetylcholine receptors (nAChRs) found both in the neuromuscular junction and central nervous system. This family is further divided into subfamilies based on the number of amino acids between cysteine residues. The exquisite subtype selectivity of certain a-conotoxins has been key to the characterization of native nAChR isoforms involved in modulation of neurotransmitter release, the pathophysiol-ogy of Parkinson's disease and nociception. Structure/function characterization of a-conotoxins has led to the development of analogs with improved potency and/or subtype selectivity. Cyclization of the backbone structure and addition of lipo-philic moieties has led to improved stability and bioavailability of a-conotoxins, thus paving the way for orally available therapeutics. The recent advances in phylogeny, exogenomics and molecular modeling promises the discovery of an even greater number of a-conotoxins and analogs with improved selectivity for specific subtypes of nAChRs.

  4. Schizophrenia and the alpha7 nicotinic acetylcholine receptor.

    Martin, Laura F; Freedman, Robert

    2007-01-01

    In addition to the devastating symptoms of psychosis, many people with schizophrenia also suffer from cognitive impairment. These cognitive symptoms lead to marked dysfunction and can impact employability, treatment adherence, and social skills. Deficits in P50 auditory gating are associated with attentional impairment and may contribute to cognitive symptoms and perceptual disturbances. This nicotinic cholinergic-mediated inhibitory process represents a potential new target for therapeutic intervention in schizophrenia. This chapter will review evidence implicating the nicotinic cholinergic, and specifically, the alpha7 nicotinic receptor system in the pathology of schizophrenia. Impaired auditory sensory gating has been linked to the alpha7 nicotinic receptor gene on the chromosome 15q14 locus. A majority of persons with schizophrenia are heavy smokers. Although nicotine can acutely reverse diminished auditory sensory gating in people with schizophrenia, this effect is lost on a chronic basis due to receptor desensitization. The alpha7 nicotinic agonist 3-(2,4 dimethoxy)benzylidene-anabaseine (DMXBA) can also enhance auditory sensory gating in animal models. DMXBA is well tolerated in humans and a new study in persons with schizophrenia has found that DMXBA enhances both P50 auditory gating and cognition. alpha7 Nicotinic acetylcholine receptor agonists appear to be viable candidates for the treatment of cognitive disturbances in schizophrenia. PMID:17349863

  5. Acetylcholine esterase activity in mild cognitive impairment and Alzheimer's disease

    Impairment of cholinergic neurotransmission is a well-established fact in Alzheimer's disease (AD), but there is controversy about its relevance at the early stages of the disease and in mild cognitive impairment (MCI). In vivo positron emission tomography imaging of cortical acetylcholine esterase (AChE) activity as a marker of cholinergic innervation that is expressed by cholinergic axons and cholinoceptive neurons has demonstrated a reduction of this enzyme activity in manifest AD. The technique is also useful to measure the inhibition of cerebral AChE induced by cholinesterase inhibitors for treatment of dementia symptoms. A reduction of cortical AchE activity was found consistently in all studies of AD and in few cases of MCI who later concerted to AD. The in vivo findings in MCI and very mild AD are still preliminary, and studies seem to suggest that cholinergic innervation and AChE as the main degrading enzyme are both reduced, which might result in partial compensation of their effect. (orig.)

  6. Bolus injection of acetylcholine terminates atrial fibrillation in rats.

    Fleidervish, Ilya A; Goldberg, Yuri; Ovsyshcher, I Eli

    2008-01-28

    It is well established that a tonic increase in the availability of the atrial muscarinic K(+) channels, either by enhanced vagal tone or by steady infusion of a low-dose of cholinergic or adenosine receptor agonists, promotes the genesis of atrial fibrillation. Here, we aimed to test the hypothesis that bolus administration of a muscarinic receptor agonist would destabilize and terminate atrial arrhythmia by uniformly and transiently activating K(+) channels throughout the atria, and that if the agonist was rapidly hydrolysable, it would dissipate before the more tonic, pro-arrhythmic effects could take hold. The episodes of untreated atrial fibrillation, induced in anesthetized rats by programmed electrical stimulation via trans-esophageal bipolar catheter, lasted on average 8.6+/-2.2 min (n=32). Intravenous injection of a model hydrolysable muscarinic agonist, acetylcholine (0.2 mg/kg body weight), converted atrial fibrillation into sinus rhythm within 8.4+/-1.9 s (n=10, Ppre-atrial fibrillation values within 10-20 s of injection. In conclusion, our evidence indicates that bolus administration of rapidly hydrolysable muscarinic agonist could be an effective way to pharmacologically terminate atrial fibrillation and restore sinus rhythm. PMID:18078927

  7. The use of FTA cards for transport and detection of gyrA mutation of Campylobacter jejuni from poultry.

    Sierra-Arguello, Y M; Faulkner, O; Tellez, G; Hargis, B M; Pinheiro do Nascimento, V

    2016-04-01

    The purpose of the present study was to evaluate a technique involving the use of commercially available FTA classic card (Whatman) for transporting and detection of DNA to use in PCR analysis and genetic sequencing of Campylobacter jejuni of poultry origin. Fifty isolates of Campylobacter jejuni were obtained from broiler carcasses in Rio Grande do Sul, Brazil. Antimicrobial susceptibility testing to ciprofloxacin revealed that all 50 isolates were resistant to ciprofloxacin. Each isolate was transferred to Brucella broth tubes and incubated overnight at 41.5°C. Cell cultures were diluted to match a McFarland Turbidity Standard 0.5, and 110 μL of the cell suspension were applied to one circle on Whatman FTA classic cards. The samples were then covered and allowed to dry at room temperature. Cards were identified and stored at room temperature until further use (3 mo after collection). FTA cards were shipped for analysis to the Department of Poultry Science, University of Arkansas. Amplification of the Campylobacter gyrA gene was successful and demonstrated strong bands for a large amplicon for all 50 samples preserved on FTA cards. Mutations present in each gene were confirmed by DNA sequencing. Then, 7 samples were chosen for the sequencing. The detection of a mutation regarding ciprofloxacin-resistant isolates revealed that 7 samples had a mutation in the gyrA gene. In conclusion, the characteristics of the profiles suggest that the DNA has maintained its integrity after 3 mo of storage at room temperature and is a suitable template for PCR and sequencing from Campylobacter samples. The application of this technology has potential in numerous methodologies, especially when working in remote areas and in developing countries where access to laboratory facilities and equipment is limited. PMID:26769268

  8. Comparison of heparin and EDTA transport tubes for detection of cytomegalovirus in leukocytes by shell vial assay, pp65 antigenemia assay, and PCR.

    Storch, G A; Gaudreault-Keener, M; Welby, P C

    1994-01-01

    The anticoagulants heparin and EDTA were compared for inhibitory effects on the detection of cytomegalovirus from washed leukocytes in specimen transport tubes. Evaluation was made by the centrifugation/shell vial culture technique, the pp65 antigenemia assay, and PCR. For each assay, the results with heparin and EDTA were equivalent.

  9. Control of unauthorized transportation of nuclear and radioactive materials across state territories and borders: detection, response and decision support

    A new solution to control the illicit transportation of nuclear and radioactive materials is proposed and described. This solution consists in the creation of a system of gamma and gamma-neutron radiation monitors and fundamentally new software/hardware package RAVEN (Radiation Alarm and Video Event Notification) which integrates different type monitors in a single network. The main purpose of this system is to analyze and store data coming from radiation monitors, to process these data and to help the user to interpret them. This ensures the user's correct response to all the alarms triggered by radiation monitors and indicating the presence of radioactive and/or nuclear materials in scanned objects. The developed system can integrate fixed radiation monitors that can be installed in different sites within not only one country but in different sites worldwide in a single network. The system can be adapted to the local conditions and allows the user: (i) To detect minimum quantities of special nuclear and radioactive materials (specified by the national and international requirements) by their gamma and/or neutron radiation; (ii) To acquire, store and analyze digital data and video images related to cargos with radioactive materials crossing a state border or an object limits; (iii) To make these data accessible to users at different levels ensuring effective operation of both central alarm stations (state, regional or agency center) and local alarm stations (border cross points or object limits). (author)

  10. Control of unauthorized transportation of nuclear and radioactive materials across state territories and borders - Detection, response and decision support

    A new solution to control the illicit transportation of nuclear and radioactive materials is proposed and described. This solution consists in the creation of a system of gamma and gamma-neutron radiation monitors and fundamentally new software/hardware package RAVEN (Radiation Alarm and Video Event Notification) which integrates different type monitors in a single network. The main purpose of this system is to analyze and store data coming from radiation monitors, to process these data and to help the user to interpret them. This ensures the user's correct response to all the alarms triggered by radiation monitors and indicating the presence of radioactive and/or nuclear materials in scanned objects. The developed system can integrate fixed radiation monitors that can be installed in different sites within not only one country but in different sites worldwide in a single network. The system can be adapted to the local conditions and allows the user: (i) to detect minimum quantities of special nuclear and radioactive materials (specified by the national and international requirements) by their gamma and/or neutron radiation; (ii) to acquire, store and analyze digital data and video images related to cargos with radioactive materials crossing a state border or an object limits; (iii) to make these data accessible to users at different levels ensuring effective operation of both central alarm stations (state, regional or agency center) and local alarm stations (border cross points or object limits). (author)

  11. Inhibition of human α7 nicotinic acetylcholine receptors by cyclic monoterpene carveol.

    Lozon, Yosra; Sultan, Ahmed; Lansdell, Stuart J; Prytkova, Tatiana; Sadek, Bassem; Yang, Keun-Hang Susan; Howarth, Frank Christopher; Millar, Neil S; Oz, Murat

    2016-04-01

    Cyclic monoterpenes are a group of phytochemicals with antinociceptive, local anesthetic, and anti-inflammatory actions. Effects of cyclic monoterpenes including vanilin, pulegone, eugenole, carvone, carvacrol, carveol, thymol, thymoquinone, menthone, and limonene were investigated on the functional properties of the cloned α7 subunit of the human nicotinic acetylcholine receptor expressed in Xenopus oocytes. Monoterpenes inhibited the α7 nicotinic acetylcholine receptor in the order carveol>thymoquinone>carvacrol>menthone>thymol>limonene>eugenole>pulegone≥carvone≥vanilin. Among the monoterpenes, carveol showed the highest potency on acetylcholine-induced responses, with IC50 of 8.3µM. Carveol-induced inhibition was independent of the membrane potential and could not be reversed by increasing the concentration of acetylcholine. In line with functional experiments, docking studies indicated that cyclic monoterpenes such as carveol may interact with an allosteric site located in the α7 transmembrane domain. Our results indicate that cyclic monoterpenes inhibit the function of human α7 nicotinic acetylcholine receptors, with varying potencies. PMID:26849939

  12. Loss of Acetylcholine Signaling Reduces Cell Clearance Deficiencies in Caenorhabditis elegans.

    Sérgio M Pinto

    Full Text Available The ability to eliminate undesired cells by apoptosis is a key mechanism to maintain organismal health and homeostasis. Failure to clear apoptotic cells efficiently can cause autoimmune diseases in mammals. Genetic studies in Caenorhabditis elegans have greatly helped to decipher the regulation of apoptotic cell clearance. In this study, we show that the loss of levamisole-sensitive acetylcholine receptor, but not of a typical neuronal acetylcholine receptor causes a reduction in the number of persistent cell corpses in worms suffering from an engulfment deficiency. This reduction is not caused by impaired or delayed cell death but rather by a partial restoration of the cell clearance capacity. Mutants in acetylcholine turn-over elicit a similar phenotype, implying that acetylcholine signaling is the process responsible for these observations. Surprisingly, tissue specific RNAi suggests that UNC-38, a major component of the levamisole-sensitive receptor, functions in the dying germ cell to influence engulfment efficiency. Animals with loss of acetylcholine receptor exhibit a higher fraction of cell corpses positive for the "eat-me" signal phosphatidylserine. Our results suggest that modulation by ion channels of ion flow across plasma membrane in dying cells can influence the dynamics of phosphatidylserine exposure and thus clearance efficiency.

  13. Cognitive effects of dopamine depletion in the context of diminished acetylcholine signaling capacity in mice

    Lilia Zurkovsky

    2013-01-01

    A subset of patients with Parkinson’s disease acquires a debilitating dementia characterized by severe cognitive impairments (i.e. Parkinson’s disease dementia; PDD. Brains from PDD patients show extensive cholinergic loss as well as dopamine (DA depletion. We used a mutant mouse model to directly test whether combined cholinergic and DA depletion leads to a cognitive profile resembling PDD. Mice carrying heterozygous deletion of the high-affinity, hemicholinium-3-sensitive choline transporter (CHTHET show reduced levels of acetylcholine throughout the brain. We achieved bilateral DA depletion in CHTHET and wild-type (WT littermates via intra-striatal infusion of 6-hydroxydopamine (6-OHDA, or used vehicle as control. Executive function and memory were evaluated using rodent versions of cognitive tasks commonly used with human subjects: the set-shifting task and spatial and novel-object recognition paradigms. Our studies revealed impaired acquisition of attentional set in the set-shifting paradigm in WT-6OHDA and CHTHET-vehicle mice that was exacerbated in the CHTHET-6OHDA mice. The object recognition test following a 24-hour delay was also impaired in CHTHET-6OHDA mice compared with all other groups. Treatment with acetylcholinesterase (AChE inhibitors physostigmine (0.05 or 0.1 mg/kg and donepezil (0.1 and 0.3 mg/kg reversed the impaired object recognition of the CHTHET-6OHDA mice. Our data demonstrate an exacerbated cognitive phenotype with dual ACh and DA depletion as compared with either insult alone, with traits analogous to those observed in PDD patients. The results suggest that combined loss of DA and ACh could be sufficient for pathogenesis of specific cognitive deficits in PDD.

  14. Evaluation of PET Radioligands for the neuronal nicotinic acetylcholine receptor

    Full text: A-186253.1, a compound made by Abbott laboratories, was labelled with carbon-11 and evaluated as a PET ligand for the neuronal nicotinic acetylcholine receptor (nAChR). The compound was labelled with C-11 by methylation with 11C-MeI of the desmethyl precursor A-183828.1. The affinity of A-186253.1 for the α4β2 and the α7 subtype of the nAChR was determined in displacement studies. PET-studies were performed in rats and pigs Inhibitory constants (Ki) versus cytsine were 461 ± 99 pM for A-186253.1 and versus α-Bungarotoxin >100 μM. which means a very high selectivity for the α4β2-receptor (>227,000). Highest uptake of [11C]-A-186253.1 was observed in the thalamus where an increase in radiotracer uptake was seen until 45 min p.i.. Thereafter, the radiotracer concentration remained constant until the end of the scan indicating slow washout of [11C]-A-186253.1. Application of cold A-186253.1 (0.5 mg/kg) 40 min p.i. resulted in a decrease in radiotracer concentration in the thalamus and the cortex indicating displacement of [11C]-A-186253.1. Blockade studies with cytisine (0.5 mg/kg), a selective ligand for the α4β2 nicotinic receptor, showed just a slight reduction of the radioligand uptake in the thalamus and in the cortex whereas the blockade with cold A-186253.1 (1 mg/kg) resulted in a 50 % reduction. These results suggest, that 50 % of the [11C]-A-186253.1 in the brain corresponds to specifically bound radioligand, but not to the α4β2 subtype of the nicotinic receptor. (author)

  15. Acetylcholine receptors in dementia and mild cognitive impairment

    Sabri, Osama; Kendziorra, Kai [University of Leipzig, Department of Nuclear Medicine, Leipzig (Germany); Wolf, Henrike; Gertz, Hermann-Josef [University of Leipzig, Department of Psychiatry, Leipzig (Germany); Brust, Peter [Institute of Interdisciplinary Isotope Research, Leipzig (Germany)

    2008-03-15

    To clarify whether changes in the cholinergic transmission occur early in the course of Alzheimer's disease (AD), we carried out positron emission tomography (PET) with the radioligand 2-[{sup 18}F]F-A-85380, which is supposed to be specific for {alpha}4{beta}2 nicotinic acetylcholine receptors (nAChRs). We included patients with moderate to severe AD and patients with amnestic mild cognitive impairment (MCI), presumed to present preclinical AD. Both patients with AD and MCI showed significant reductions in {alpha}4{beta}2 nAChRs in brain regions typically affected by AD pathology. These findings indicate that a reduction in {alpha}4{beta}2 nAChRs occurs during early symptomatic stages of AD. The {alpha}4{beta}2 nAChR availability in these regions correlated with the severity of cognitive impairment, indicating a stage sensitivity of the {alpha}4{beta}2 nAChR status. Together, our results provide evidence for the potential of 2-[{sup 18}]F-A-85380 nAChR PET in the diagnosis of patients at risk for AD. Because of the extraordinary long acquisition time with 2-[{sup 18}F]F-A-85380, we developed the new {alpha}4{beta}2 nAChR-specific radioligands (+)- and (-)-[{sup 18}F]norchloro-fluoro-homoepibatidine (NCFHEB) and evaluated them preclinically. (-)-[{sup 18}F]NCFHEB shows twofold higher brain uptake and significantly shorter acquisition times. Therefore, (-)-[{sup 18}F]NCFHEB should be a suitable radioligand for larger clinical investigations. (orig.)

  16. Acetylcholine receptors in dementia and mild cognitive impairment

    To clarify whether changes in the cholinergic transmission occur early in the course of Alzheimer's disease (AD), we carried out positron emission tomography (PET) with the radioligand 2-[18F]F-A-85380, which is supposed to be specific for α4β2 nicotinic acetylcholine receptors (nAChRs). We included patients with moderate to severe AD and patients with amnestic mild cognitive impairment (MCI), presumed to present preclinical AD. Both patients with AD and MCI showed significant reductions in α4β2 nAChRs in brain regions typically affected by AD pathology. These findings indicate that a reduction in α4β2 nAChRs occurs during early symptomatic stages of AD. The α4β2 nAChR availability in these regions correlated with the severity of cognitive impairment, indicating a stage sensitivity of the α4β2 nAChR status. Together, our results provide evidence for the potential of 2-[18]F-A-85380 nAChR PET in the diagnosis of patients at risk for AD. Because of the extraordinary long acquisition time with 2-[18F]F-A-85380, we developed the new α4β2 nAChR-specific radioligands (+)- and (-)-[18F]norchloro-fluoro-homoepibatidine (NCFHEB) and evaluated them preclinically. (-)-[18F]NCFHEB shows twofold higher brain uptake and significantly shorter acquisition times. Therefore, (-)-[18F]NCFHEB should be a suitable radioligand for larger clinical investigations. (orig.)

  17. A reactive transport model for the geochemical response, detection and potential mitigation of CO2 leakage into a confined aquifer

    Maher, K.; Druhan, J. L.; Vialle, S.; Benson, S. M.; Agarwal, A.

    2013-12-01

    Long-term storage of anthropogenic CO2 in the subsurface generally assumes that caprock formations will serve as physical barriers to upward migration of CO2. Stability and coherence of the caprocks are thus important criteria for site selection, but caprock integritycannot be guaranteed with total certainty over the lifetime of the project. As a result, carbon capture and storage projects require reliable techniques to monitor geologic storage sites for newly formed leaks, and the ability to rapidly deploy mitigation measures should leakage occur. Here, we present two-dimensional reactive transport simulations to evaluate the hydrogeochemical characteristics of a newly formed CO2 leak into an overlying reservoir. Simulations use the ToughReact multi-component reactive transport code and hypothetical reservoir characteristics. We focus on the comparatively short time period of days to months following formation of the leak to consider (1) geochemical shifts in formation water indicative of the leak, (2) hydrodynamics of pumping wells in the vicinity of the leak, and (3) delivery of a sealant to the leak through an adjacent well bore. Our results suggest that characteristic shifts in pH and dissolved inorganic carbon might be detected in down-gradient mentoring wells prior to the breakthrough of CO2, and could offer a potential means of identifying small and newly formed leaks. Injecting water into the aquifer through pumping wells in the vicinity of the leak provides a hydrodynamic control that can prevent CO2 from reaching the top of the reservoir, but this action will likely have only minor influence on the rate of leakage through the caprock defect. Injection of a hypothetical sealant through an adjacent pumping well is considered using an aqueous solute with pH-dependent equilibrium constraints such that the species is soluble in the basic pH range but forms a precipitate at neutral to acidic pH conditions associated with CO2-rich water. Injection of this

  18. Insensitive Acetylcholine Receptor Conferring Resistance of Plutella xylostella to Nereistoxin Insecticides

    CHENG Luo-gen; YU Guang; CHEN Zi-hao; LI Zhong-yin

    2008-01-01

    The combinative rate measurement of (3-[Ⅰ125] iodotyrosyl) α-bungarotoxin was applied in the analysis of the relation between nerve acetylcholine receptor and three types of insecticide resistance in diamondback moth, Plutella xylostella (L.). In the dimehypo-resistant strain and in the cartap-resistant strain, the nerve acetylcholine receptor showed the remarkable insensitivity to dimehypo and cartap, of which the binding rate to ligand was approximately 66 and 60%, respectively, of the susceptible strain. The sensitivity to deltamethrin in the deltamethrin-resistant strain did not show visible change. These results indicated that the decline in the sensitivity of nerve acetylcholine receptor to insecticide might be a potential mechanism to nereistoxin insecticides resistance in the diamondback moth.

  19. Prejunctional inhibition of norepinephrine release caused by acetylcholine in the human saphenous vein

    We performed experiments to determine whether or not acetylcholine exerts a prejunctional inhibitory effect on adrenergic neurotransmission in the human blood vessel wall. Rings of human greater saphenous veins were prepared 2 to 15 hours after death and mounted for isometric tension recording in organ chambers filled with Krebs-Ringer solution. Acetylcholine depressed contractile responses to electric activation of the sympathetic nerve endings significantly more than those to exogenous norepinephrine; the relaxations caused by the cholinergic transmitter were antagonized by atropine. Helical strips were incubated with [/sub 3/H]norepinephrine and mounted for superfusion. Electric stimulation augmented the fractional release of labeled norepinephrine. Acetylcholine caused a depression of the evoked /sub 3/H release which was antagonized by atropine but not by hexamethonium. These experiments demonstrate that, as in animal cutaneous veins, there are prejunctional inhibitory muscarinic receptors on the adrenergic nerve endings in the human saphenous vein. By contrast, the human vein also contains postjunctional inhibitory muscarinic receptors

  20. Reduced acetylcholine synthesis in Alzheimer's disease is a clinically relevant change

    This paper presents a study of patients in the presenium. Psychological assessment was carried out to provide measures of relative severity of dementia, with which pathological and chemical indices of impairment could be compared. Fresh cortical biopsy tissue permitted the assay of ChAT activity, and also the determination of acetylcholine synthesis in a preparation enriched in cortical synaptosomes. Additionally, choline uptake has been measured for comparison. Nuerosurgical samples from all patients were handled and processed for measuring acetylcholine synthesis by incorporation of U-14C-glucoase into C 14-acetylcholine in neocortical tissue prisms. Cortical sections from most of the patients were found on light microscopy to contain the characteristic changes of Alzheimer's disease

  1. Influence of melatonin on the development of functional nicotinic acetylcholine receptors in cultured chick retinal cells

    L.F.S. Sampaio

    2005-04-01

    Full Text Available The influence of melatonin on the developmental pattern of functional nicotinic acetylcholine receptors was investigated in embryonic 8-day-old chick retinal cells in culture. The functional response to acetylcholine was measured in cultured retina cells by microphysiometry. The maximal functional response to acetylcholine increased 2.7 times between the 4th and 5th day in vitro (DIV4, DIV5, while the Bmax value for [125I]-alpha-bungarotoxin was reduced. Despite the presence of alpha8-like immunoreactivity at DIV4, functional responses mediated by alpha-bungarotoxin-sensitive nicotinic acetylcholine receptors were observed only at DIV5. Mecamylamine (100 µM was essentially without effect at DIV4 and DIV5, while dihydro-ß-erythroidine (10-100 µM blocked the response to acetylcholine (3.0 nM-2.0 µM only at DIV4, with no effect at DIV5. Inhibition of melatonin receptors with the antagonist luzindole, or melatonin synthesis by stimulation of D4 dopamine receptors blocked the appearance of the alpha-bungarotoxin-sensitive response at DIV5. Therefore, alpha-bungarotoxin-sensitive receptors were expressed in retinal cells as early as at DIV4, but they reacted to acetylcholine only after DIV5. The development of an alpha-bungarotoxin-sensitive response is dependent on the production of melatonin by the retinal culture. Melatonin, which is produced in a tonic manner by this culture, and is a key hormone in the temporal organization of vertebrates, also potentiates responses mediated by alpha-bungarotoxin-sensitive receptors in rat vas deferens and cerebellum. This common pattern of action on different cell models that express alpha-bungarotoxin-sensitive receptors probably reflects a more general mechanism of regulation of these receptors.

  2. [Intern(euron)al affairs : The role of specific neocortical interneuron classes in the interaction between acetylcholine and GABAergic anesthetics].

    Liebig, L; Grasshoff, C; Hentschke, H

    2016-08-01

    Acetylcholine is a neuromodulator which is released throughout the central nervous system and plays an essential role in consciousness and cognitive processes including attention and learning. Due to its 'activating' effect on the neuronal and behavioral level its interaction with anesthetics has long been of interest to anesthesiologists. It is widely held that a reduction of the release of acetylcholine by general anesthetics constitutes part of the anesthetic effect. This notion is backed by numerous human and animal studies, but is also in seeming contradiction to findings that acetylcholine activates specific classes of inhibitory neurons: if acetylcholine excites elements within the neuronal network responsible for the release of the inhibitory neurotransmitter γ-aminobutyric acid (GABA), its withdrawal should diminish, not enhance, the effect of anesthetics.Focusing on cortical circuits, we present an overview of recent advances in cellular neurophysiology, particularly the interactions between inhibitory neuron classes, which provide insights on the interaction between acetylcholine and GABA. PMID:27380048

  3. Increases in muscle Ca2+ mediate changes in acetylcholinesterase and acetylcholine receptors caused by muscle contraction.

    Rubin, L L

    1985-01-01

    The synthesis of acetylcholinesterase (AcChoE; acetylcholine acetylhydrolase, EC 3.1.1.7) and of acetylcholine receptors (AcChoR) by cultured rat muscle fibers is influenced strongly by the level of muscle contractile activity. If fibers are grown in the presence of tetrodotoxin (TTX) to block spontaneous contraction, the total amount of AcChoE decreases markedly, as does the percentage of AcChoE assembled as the collagen-tailed presumed synaptic form of the enzyme. Under these conditions, ho...

  4. Autophagic flux data in differentiated C2C12 myotubes following exposure to acetylcholine and caffeine.

    Bloemberg, Darin; Quadrilatero, Joe

    2016-06-01

    The C2C12 line of mouse myoblasts is a useful cell culture model in which to conduct in vitro analyses related to skeletal muscle. Here we present data regarding the autophagic response induced by two chemicals known to influence calcium release and contraction in skeletal muscles and C2C12 cells: acetylcholine and caffeine. More specifically, by concurrently administering acetylcholine or caffeine along with chloroquine to differentiated myotubes for various amounts of time and assessing the protein expression of LC3 and p62, we report data on the relative level of autophagic flux induced by these two calcium- and contraction-regulating chemicals. PMID:27054179

  5. Autophagic flux data in differentiated C2C12 myotubes following exposure to acetylcholine and caffeine

    Darin Bloemberg

    2016-06-01

    Full Text Available The C2C12 line of mouse myoblasts is a useful cell culture model in which to conduct in vitro analyses related to skeletal muscle. Here we present data regarding the autophagic response induced by two chemicals known to influence calcium release and contraction in skeletal muscles and C2C12 cells: acetylcholine and caffeine. More specifically, by concurrently administering acetylcholine or caffeine along with chloroquine to differentiated myotubes for various amounts of time and assessing the protein expression of LC3 and p62, we report data on the relative level of autophagic flux induced by these two calcium- and contraction-regulating chemicals.

  6. Enhanced self-administration of alcohol in muscarinic acetylcholine M4 receptor knockout mice

    de la Cour, Cecilie; Sørensen, Gunnar; Wörtwein, Gitta;

    2015-01-01

    Modulation of cholinergic neurotransmission via nicotinic acetylcholine receptors is known to alter alcohol-drinking behavior. It is not known if muscarinic acetylcholine receptor subtypes have similar effects. The muscarinic M4 receptor is highly expressed in the brain reinforcement system and i......4+/+ littermates. The highest alcohol concentration used (10%) did not immediately result in divergent drinking patterns, but after 4 weeks of 10% alcohol self-administration, baseline levels as well as a pattern of M4-/- mice consuming more alcohol than their M4+/+ controls were re...... as a potential target for pharmacological (positive allosteric modulators or future agonists) treatment of alcohol use disorders....

  7. Inhibition of cortical acetylcholine release and cognitive performance by histamine H3 receptor activation in rats.

    Blandina, P.; Giorgetti, M.; L. Bartolini; M.Cecchi; Timmerman, H.; Leurs, R.; Pepeu, G; Giovannini, M. G.

    1996-01-01

    1. The effects of histamine and agents at histamine receptors on spontaneous and 100 mM K(+)-evoked release of acetylcholine, measured by microdialysis from the cortex of freely moving, rats, and on cognitive tests are described. 2. Local administration of histamine (0.1-100 microM) failed to affect spontaneous but inhibited 100 mM K(+)-stimulated release of acetylcholine up to about 50%. The H3 receptor agonists (R)-alpha-methylhistamine (RAMH) (0.1-10 microM), imetit (0.01-10 microM) and im...

  8. Interaction of ibogaine with human α3β4-nicotinic acetylcholine receptors in different conformational states

    Arias, Hugo R.; Rosenberg, Avraham; Targowska-Duda, Katarzyna M.; Feuerbach, Dominik; Yuan, Xiao Juan; Jozwiak, Krzysztof; Moaddel, Ruin; Wainer, Irving W.

    2015-01-01

    The interaction of ibogaine and phencyclidine (PCP) with human (h) α3β4-nicotinic acetylcholine receptors (AChRs) in different conformational states was determined by functional and structural approaches including, radioligand binding assays, Ca2+ influx detections, and thermodynamic and kinetics measurements. The results established that (a) ibogaine inhibits (±)-epibatidine-induced Ca2+ influx in hα3β4 AChRs with ~9-fold higher potency than that for PCP, (b) [3H]ibogaine binds to a single site in the hα3β4 AChR ion channel with relatively high affinity (Kd = 0.46 ± 0.06 µM), and ibogaine inhibits [3H]ibogaine binding to the desensitized hα3β4 AChR with slightly higher affinity compared to the resting AChR. This is explained by a slower dissociation rate from the desensitized ion channel compared to the resting ion channel, and (c) PCP inhibits [3H]ibogaine binding to the hα3β4 AChR, suggesting overlapping sites. The experimental results correlate with the docking simulations suggesting that ibogaine and PCP interact with a binding domain located between the serine (position 6′) and valine/phenylalanine (position 13′) rings. This interaction is mediated mainly by van der Waals contacts, which is in agreement with the observed enthalpic contribution determined by non-linear chromatography. However, the calculated entropic contribution also indicates local conformational changes. Collectively our data suggest that ibogaine and PCP bind to overlapping sites located between the serine and valine/phenylalanine rings, to finally block the AChR ion channel, and in the case of ibogaine, to probably maintain the AChR in the desensitized state for longer time. PMID:20684041

  9. Interaction of ibogaine with human alpha3beta4-nicotinic acetylcholine receptors in different conformational states.

    Arias, Hugo R; Rosenberg, Avraham; Targowska-Duda, Katarzyna M; Feuerbach, Dominik; Yuan, Xiao Juan; Jozwiak, Krzysztof; Moaddel, Ruin; Wainer, Irving W

    2010-09-01

    The interaction of ibogaine and phencyclidine (PCP) with human (h) alpha3beta4-nicotinic acetylcholine receptors (AChRs) in different conformational states was determined by functional and structural approaches including, radioligand binding assays, Ca2+ influx detections, and thermodynamic and kinetics measurements. The results established that (a) ibogaine inhibits (+/-)-epibatidine-induced Ca2+ influx in h(alpha)3beta4 AChRs with approximately 9-fold higher potency than that for PCP, (b) [3H]ibogaine binds to a single site in the h(alpha)3beta4 AChR ion channel with relatively high affinity (Kd = 0.46 +/- 0.06 microM), and ibogaine inhibits [3H]ibogaine binding to the desensitized h(alpha)3beta4 AChR with slightly higher affinity compared to the resting AChR. This is explained by a slower dissociation rate from the desensitized ion channel compared to the resting ion channel, and (c) PCP inhibits [3H]ibogaine binding to the h(alpha)3beta4 AChR, suggesting overlapping sites. The experimental results correlate with the docking simulations suggesting that ibogaine and PCP interact with a binding domain located between the serine (position 6') and valine/phenylalanine (position 13') rings. This interaction is mediated mainly by van der Waals contacts, which is in agreement with the observed enthalpic contribution determined by non-linear chromatography. However, the calculated entropic contribution also indicates local conformational changes. Collectively our data suggest that ibogaine and PCP bind to overlapping sites located between the serine and valine/phenylalanine rings, to finally block the AChR ion channel, and in the case of ibogaine, to probably maintain the AChR in the desensitized state for longer time. PMID:20684041

  10. Transient Receptor Potential Channel Opening Releases Endogenous Acetylcholine, which Contributes to Endothelium-Dependent Relaxation Induced by Mild Hypothermia in Spontaneously Hypertensive Rat but Not Wistar-Kyoto Rat Arteries.

    Zou, Q; Leung, S W S; Vanhoutte, P M

    2015-08-01

    Mild hypothermia causes endothelium-dependent relaxations, which are reduced by the muscarinic receptor antagonist atropine. The present study investigated whether endothelial endogenous acetylcholine contributes to these relaxations. Aortic rings of spontaneously hypertensive rats (SHRs) and normotensive Wistar-Kyoto (WKY) rats were contracted with prostaglandin F2 α and exposed to progressive mild hypothermia (from 37 to 31°C). Hypothermia induced endothelium-dependent, Nω-nitro-l-arginine methyl ester-sensitive relaxations, which were reduced by atropine, but not by mecamylamine, in SHR but not in WKY rat aortae. The responses in SHR aortae were also reduced by acetylcholinesterase (the enzyme responsible for acetylcholine degradation), bromoacetylcholine (inhibitor of acetylcholine synthesis), hemicholinium-3 (inhibitor of choline uptake), and vesamicol (inhibitor of acetylcholine release). The mild hypothermia-induced relaxations in both SHR and WKY rat aortae were inhibited by AMTB [N-(3-aminopropyl)-2-[(3-methylphenyl)methoxy]-N-(2-thienylmethyl)-benzamide; the transient receptor potential (TRP) M8 inhibitor]; only those in SHR aortae were inhibited by HC-067047 [2-methyl-1-[3-(4-morpholinyl)propyl]-5-phenyl-N-[3-(trifluoromethyl)phenyl]-1H-pyrrole-3-carboxamide; TRPV4 antagonist] while those in WKY rat aortae were reduced by HC-030031 [2-(1,3-dimethyl-2,6-dioxo-1,2,3,6-tetrahydro-7H-purin-7-yl)-N-(4-isopropylphenyl)acetamide; TRPA1 antagonist]. The endothelial uptake of extracellular choline and release of cyclic guanosine monophosphate was enhanced by mild hypothermia and inhibited by HC-067047 in SHR but not in WKY rat aortae. Compared with WKY rats, the SHR preparations expressed similar levels of acetylcholinesterase and choline acetyltransferase, but a lesser amount of vesicular acetylcholine transporter, located mainly in the endothelium. Thus, mild hypothermia causes nitric oxide-dependent relaxations by opening TRPA1 channels in WKY rat aortae

  11. [{sup 123}I]-3-Iodcytisin as possible radiotracer for the imaging of nicotinic acetylcholine receptors using single photon emission computer tomography; [{sup 123}I]-3-Iodcytisin als moeglicher Radiotracer fuer die Darstellung der nikotinergen Acetylcholin Rezeptoren mittels Single-Photon-Emissions-Computertomographie

    Paulik, Dagmar Julia

    2015-03-06

    For the synthesis of [{sup 123}I]-3-Iodcytisin as possible radiotracer for the imaging of nicotinic acetylcholine (nACh) receptors using SPECT two different technologies were used: the radio-iodination with iodogen and the radio-iodination with nitric acid. The latter one showed higher efficiency. The radiotracer will allow to detect degenerative processes and other nACh-depending diseases in the brain (Alzheimer, Parkinson) and to observe the progress. The autoradiography is aimed to the imaging of the nACh receptors in the brain bypassing the brain-blood barrier. The highest activity was measured in the thalamus of mice and rat brains.

  12. A shallow subsurface controlled release facility in Bozeman, Montana, USA, for testing near surface CO2 detection techniques and transport models

    Spangler, Lee H. [Montana State Univ., Bozeman, MT (United States). Dept. of Chemistry and Biochemistry; Dobeck, Laura M. [Montana State Univ., Bozeman, MT (United States). Dept. of Chemistry and Biochemistry; Repasky, Kevin S. [Montana State Univ., Bozeman, MT (United States). Dept. of Electrical and Computer Engineering; Nehrir, Amin R. [Montana State Univ., Bozeman, MT (United States). Dept. of Electrical and Computer Engineering; Humphries, Seth D. [Montana State Univ., Bozeman, MT (United States). Dept. of Electrical and Computer Engineering; Barr, Jamie L. [Montana State Univ., Bozeman, MT (United States). Dept. of Electrical and Computer Engineering; Keith, Charlie J. [Montana State Univ., Bozeman, MT (United States). Dept. of Electrical and Computer Engineering; Shaw, Joseph A. [Montana State Univ., Bozeman, MT (United States). Dept. of Electrical and Computer Engineering; Rouse, Joshua H. [Montana State Univ., Bozeman, MT (United States). Dept. of Electrical and Computer Engineering; Cunningham, Alfred B. [Montana State Univ., Bozeman, MT (United States). Dept. of Civil Engineering; Benson, Sally M. [Stanford Univ., CA (United States). Global Climate and Energy Project; Oldenburg, Curtis M. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Earth Sciences Div.; Lewicki, Jennifer L. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Earth Sciences Div.; Wells, Arthur W. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Earth Sciences Div.; Diehl, J. Rodney [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Earth Sciences Div.; Strazisar, Brian R. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Earth Sciences Div.; Fessenden, Julianna E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Div. of Earth and Environmental Sciences; Rahn, Thom A. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Div. of Earth and Environmental Sciences; Amonette, James E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Barr, Jon L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Pickles, William L. [Univ. of California, Santa Cruz, CA (United States). Earth and Planetary Sciences; Jacobson, James D. [Univ. of California, Santa Cruz, CA (United States). Earth and Planetary Sciences; Silver, Eli A. [Univ. of California, Santa Cruz, CA (United States). Earth and Planetary Sciences; Male, Erin J. [Univ. of California, Santa Cruz, CA (United States). Earth and Planetary Sciences; Rauch, Henry W. [Univ. of West Virginia, Morgantown, WV (United States). Dept. of Geology and Geography; Gullickson, Kadie S. [Montana State Univ., Bozeman, MT (United States). Dept. of Chemistry and Biochemistry; Trautz, Robert [Electric Power Research Inst. (EPRI), Palo Alto, CA (United States); Kharaka, Yousif [U.S. Geological Survey, Menlo Park, CA (United States); Birkholzer, Jens [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Earth Sciences Div.; Wielopolski, Lucien [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2010-03-01

    A controlled field pilot has been developed in Bozeman, Montana, USA, to study near surface CO2 transport and detection technologies. A slotted horizontal well divided into six zones was installed in the shallow subsurface. The scale and CO2 release rates were chosen to be relevant to developing monitoring strategies for geological carbon storage. The field site was characterized before injection, and CO2 transport and concentrations in saturated soil and the vadose zone were modeled. Controlled releases of CO2 from the horizontal well were performed in the summers of 2007 and 2008, and collaborators from six national labs, three universities, and the U. S. Geological Survey investigated movement of CO2 through the soil, water, plants, and air with a wide range of near surface detection techniques. An overview of these results will be presented.

  13. A shallow subsurface controlled release facility in Bozeman, Montana, USA, for testing near surface CO2 detection techniques and transport models

    Spangler, L.H.; Dobeck, L.M.; Nehrir, A.; Humphries, S.; Barr, J.; Keith, C.; Shaw, J.; Rouse, J.; Cunningham, A.; Benson, S.; Repasky, K.S.; Lewicki, J.; Wells, A.; Diehl, R.; Strazisar, B.; Fessenden, J.; Rahn, T.; Amonette, J.; Barr, J.; Pickles, W.; Jacobson, J.; Silver, E.; Male, E.; Rauch, H.; Gullickson, K.; Trautz, R.; Kharaka, Y.; Birkholzer, J.T.; Wielopolski, L.; Oldenburg, C.M.

    2009-10-20

    A controlled field pilot has been developed in Bozeman, Montana, USA, to study near surface CO2 transport and detection technologies. A slotted horizontal well divided into six zones was installed in the shallow subsurface. The scale and CO2 release rates were chosen to be relevant to developing monitoring strategies for geological carbon storage. The field site was characterized before injection, and CO2 transport and concentrations in saturated soil and the vadose zone were modeled. Controlled releases of CO2 from the horizontal well were performed in the summers of 2007 and 2008, and collaborators from six national labs, three universities, and the U.S. Geological Survey investigated movement of CO2 through the soil, water, plants, and air with a wide range of near surface detection techniques. An overview of these results will be presented.

  14. A shallow subsurface controlled release facility in Bozeman, Montana, USA, for testing near surface CO2 detection techniques and transport models

    Spangler, L.H.; Dobeck, L.M.; Repasky, K.S.; Nehrir, A.R.; Humphries, S.D.; Keith, C.J.; Shaw, J.A.; Rouse, J.H.; Cunningham, A.B.; Benson, S.M.; Oldenburg, C.M.; Lewicki, J.L.; Wells, A.W.; Diehl, J.R.; Strazisar, B.R.; Fessenden, J.E.; Rahn, T.A.; Amonette, J.E.; Barr, J.L.; Pickles, W.L.; Jacobson, J.D.; Silver, E.A.; Male, E.J.; Rauch, H.W.; Gullickson, K.S.; Trautz, R.; Kharaka, Y.; Birkholzer, J.; Wielopolski, L.

    2010-01-01

    A controlled field pilot has been developed in Bozeman, Montana, USA, to study near surface CO2 transport and detection technologies. A slotted horizontal well divided into six zones was installed in the shallow subsurface. The scale and CO2 release rates were chosen to be relevant to developing monitoring strategies for geological carbon storage. The field site was characterized before injection, and CO2 transport and concentrations in saturated soil and the vadose zone were modeled. Controlled releases of CO2 from the horizontal well were performed in the summers of 2007 and 2008, and collaborators from six national labs, three universities, and the U.S. Geological Survey investigated movement of CO2 through the soil, water, plants, and air with a wide range of near surface detection techniques. An overview of these results will be presented. ?? 2009 The Author(s).

  15. Apolipoprotein E4 reduces evoked hippocampal acetylcholine release in adult mice

    Dolejší, Eva; Liraz, O.; Rudajev, Vladimír; Zimčík, Pavel; Doležal, Vladimír; Michaelson, D. M.

    Roč. 136, č. 3 ( 2016 ), s. 503-509. ISSN 0022-3042 R&D Projects: GA MŠk(CZ) LH13269 Institutional support: RVO:67985823 Keywords : acetylcholine release * Alzheimer's disease (AD) * apolipoprotein E4 (apoE4) * hippocampus Subject RIV: FH - Neurology Impact factor: 4.281, year: 2014

  16. Acetylcholine Release in the Hippocampus and Striatum during Place and Response Training

    Pych, Jason C.; Chang, Qing; Colon-Rivera, Cynthia; Haag, Renee; Gold, Paul E.

    2005-01-01

    These experiments examined the release of acetylcholine in the hippocampus and striatum when rats were trained, within single sessions, on place or response versions of food-rewarded mazes. Microdialysis samples of extra-cellular fluid were collected from the hippocampus and striatum at 5-min increments before, during, and after training. These…

  17. Exocrine secretion of epidermal growth factor from Brunner's glands. Stimulation by VIP and acetylcholine

    Poulsen, Steen Seier

    1983-01-01

    Brunner's glands of the duodenum are innervated by cholinergic and VIP-ergic nerves, and the glands have been shown to contain epidermal growth factor (EGF). In this study the effect of VIP and acetylcholine (Ach) on secretion of EGF from Brunner's glands was investigated in the rat. Intravenous ...

  18. Functional Characterization of a Novel Class of Morantel-Sensitive Acetylcholine Receptors in Nematodes.

    Elise Courtot

    2015-12-01

    Full Text Available Acetylcholine receptors are pentameric ligand-gated channels involved in excitatory neuro-transmission in both vertebrates and invertebrates. In nematodes, they represent major targets for cholinergic agonist or antagonist anthelmintic drugs. Despite the large diversity of acetylcholine-receptor subunit genes present in nematodes, only a few receptor subtypes have been characterized so far. Interestingly, parasitic nematodes affecting human or animal health possess two closely related members of this gene family, acr-26 and acr-27 that are essentially absent in free-living or plant parasitic species. Using the pathogenic parasitic nematode of ruminants, Haemonchus contortus, as a model, we found that Hco-ACR-26 and Hco-ACR-27 are co-expressed in body muscle cells. We demonstrated that co-expression of Hco-ACR-26 and Hco-ACR-27 in Xenopus laevis oocytes led to the functional expression of an acetylcholine-receptor highly sensitive to the anthelmintics morantel and pyrantel. Importantly we also reported that ACR-26 and ACR-27, from the distantly related parasitic nematode of horses, Parascaris equorum, also formed a functional acetylcholine-receptor highly sensitive to these two drugs. In Caenorhabditis elegans, a free-living model nematode, we demonstrated that heterologous expression of the H. contortus and P. equorum receptors drastically increased its sensitivity to morantel and pyrantel, mirroring the pharmacological properties observed in Xenopus oocytes. Our results are the first to describe significant molecular determinants of a novel class of nematode body wall muscle AChR.

  19. Functional Characterization of CCHamide and Muscarinic Acetylcholine Receptor Signalling in Drosophila melanogaster

    Ren, Guilin Robin

    mutants created with the CRISP/Cas9 technique showed thatCCHamide-2 is probly an orexigenic peptide and also that is an important factor for larvaldevelopmental timing.In mammals, muscarinic acetylcholine signalling is involved in the signal transmission of theparasympathetic nervous system. However...

  20. Characterization of the positive and negative inotropic effects of acetylcholine in the human myocardium

    X.Y. Du (Xiaoyi); R.G. Schoemaker (Regien); E. Bos (Egbert); P.R. Saxena (Pramod Ranjan)

    1995-01-01

    textabstractIn the human isolated myocardium, acetylcholine (10−9 to 10−3 M) elicited a biphasic inotropic effect (a decrease in the lower and an increase in the higher concentration range) in atrial and a positive inotropic effect in ventricular trabeculae. However, under conditions of raised contr

  1. MUSCARINIC ACETYLCHOLINE RECEPTOR-EXPRESSION IN ASTROCYTES IN THE CORTEX OF YOUNG AND AGED RATS

    VANDERZEE, EA; DEJONG, GI; STROSBERG, AD; LUITEN, PGM

    1993-01-01

    The present report describes the cellular and subcellular distribution pattern of immunoreactivity to M35, a monoclonal antibody raised against purified muscarinic acetylcholine receptor protein, in astrocytes in the cerebral cortex of young and aged rats. Most M35-positive astrocytes were localized

  2. Synthesis and pharmacological evaluation of DHβE analogs as neuronal nicotinic acetylcholine receptor antagonists

    Jepsen, Tue H.; Jensen, Anders A.; Lund, Mads Henrik; Glibstrup, Emil; Kristensen, Jesper Langgaard

    2014-01-01

    Dihydro-β-erythroidine (DHβE) is a member of the Erythrina family of alkaloids and a potent competitive antagonist of the α4β2-subtype of the nicotinic acetylcholine receptors (nAChRs). Guided by an X-ray structure of DHβE in complex with an ACh binding protein, we detail the design, synthesis, and...

  3. Tying up Nicotine: New Selective Competitive Antagonist of the Neuronal Nicotinic Acetylcholine Receptors

    Petersen, Ida Nymann; Crestey, François; Jensen, Anders A; Indurthi, Dinesh C; Pedersen, Henrik; Andreasen, Jesper T; Balle, Thomas; Kristensen, Jesper L

    2015-01-01

    Conformational restriction of the pyrrolidine nitrogen in nicotine by the introduction of an ethylene bridge provided a potent and selective antagonist of the α4β2-subtype of the nicotinic acetylcholine receptors. Resolution by chiral SFC, pharmacological characterization of the two enantiomers...

  4. Distinct neural pathways mediate alpha7 nicotinic acetylcholine receptor-dependent activation of the forebrain

    Thomsen, Morten S; Hay-Schmidt, Anders; Hansen, Henrik H; Mikkelsen, Jens D

    2010-01-01

    alpha(7) nicotinic acetylcholine receptor (nAChR) agonists are candidates for the treatment of cognitive deficits in schizophrenia. Selective alpha(7) nAChR agonists, such as SSR180711, activate neurons in the medial prefrontal cortex (mPFC) and nucleus accumbens shell (ACCshell) in rats, regions...

  5. alpha(7) Nicotinic acetylcholine receptor activation prevents behavioral and molecular changes induced by repeated phencyclidine treatment

    Thomsen, Morten Skøtt; Christensen, Ditte Z; Hansen, Henrik H; Redrobe, John P; Mikkelsen, Jens D

    determined in a modified Y-maze test. Polymorphisms in the alpha(7) nicotinic acetylcholine receptor (nAChR) gene have been linked to schizophrenia. Here we demonstrate that acute administration of the selective alpha(7) nAChR partial agonist SSR180711 dose-dependently reversed the behavioral impairment...

  6. VISUALIZATION OF CHOLINOCEPTIVE NEURONS IN THE RAT NEOCORTEX - COLOCALIZATION OF MUSCARINIC AND NICOTINIC ACETYLCHOLINE-RECEPTORS

    VANDERZEE, EA; STREEFLAND, C; STROSBERG, AD; SCHRODER, H; LUITEN, PGM

    1992-01-01

    The present investigation analyzes the cellular distribution of muscarinic and nicotinic acetylcholine receptors in rat neocortex, by use of monoclonal antibodies raised against purified receptor proteins. The degree of colocalization of both types of receptors was determined by way of immunofluores

  7. Visualization of cholinoceptive neurons in the rat neocortex : colocalization of muscarinic and nicotinic acetylcholine receptors

    Zee, E.A. van der; Streefland, C.; Strosberg, A.D.; Schröder, H.; Luiten, P.G.M.

    1992-01-01

    The present investigation analyzes the cellular distribution of muscarinic and nicotinic acetylcholine receptors in rat neocortex, by use of monoclonal antibodies raised against purified receptor proteins. The degree of colocalization of both types of receptors was determined by way of immunofluores

  8. Mechanisms of the inhibition of endplate acetylcholine receptors by antiseptic chlorhexidine (experiments and models)

    Shaihutdinova, A.R.; Nikolsky, E. E.; Vyskočil, František; Skorinkin, A.I.

    2009-01-01

    Roč. 380, č. 6 (2009), s. 551-560. ISSN 0028-1298 R&D Projects: GA AV ČR(CZ) IAA500110905 Institutional research plan: CEZ:AV0Z50110509 Keywords : acetylcholine * endplate currents Subject RIV: ED - Physiology Impact factor: 2.631, year: 2009

  9. Theoretical investigation of interaction between the set of ligands and α7 nicotinic acetylcholine receptor

    Glukhova, O. E.; Prytkova, T. R.; Shmygin, D. S.

    2016-03-01

    Nicotinic acetylcholine receptors (nAChRs) are neuron receptor proteins that provide a transmission of nerve impulse through the synapses. They are composed of a pentametric assembly of five homologous subunits (5 α7 subunits for α7nAChR, for example), oriented around the central pore. These receptors might be found in the chemical synapses of central and peripheral nervous system, and also in the neuromuscular synapses. Transmembrane domain of the one of such receptors constitutes ion channel. The conductive properties of ion channel strongly depend on the receptor conformation changes in the response of binding with some molecule, f.e. acetylcholine. Investigation of interaction between ligands and acetylcholine receptor is important for drug design. In this work we investigate theoretically the interaction between the set of different ligands (such as vanillin, thymoquinone, etc.) and the nicotinic acetylcholine receptor (primarily with subunit of the α7nAChR) by different methods and packages (AutodockVina, GROMACS, KVAZAR, HARLEM, VMD). We calculate interaction energy between different ligands in the subunit using molecular dynamics. On the base of obtained calculation results and using molecular docking we found an optimal location of different ligands in the subunit.

  10. ATP–Binding Cassette Transporter Structure Changes Detected by Intramolecular Fluorescence Energy Transfer for High-Throughput Screening

    Iram, Surtaj H.; Gruber, Simon J.; Raguimova, Olga N.; Thomas, David D.; Seth L Robia

    2015-01-01

    Multidrug resistance protein 1 (MRP1) actively transports a wide variety of drugs out of cells. To quantify MRP1 structural dynamics, we engineered a “two-color MRP1” construct by fusing green fluorescent protein (GFP) and TagRFP to MRP1 nucleotide–binding domains NBD1 and NBD2, respectively. The recombinant MRP1 protein expressed and trafficked normally to the plasma membrane. Two-color MRP1 transport activity was normal, as shown by vesicular transport of [3H]17β-estradiol-17-β-(d-glucuroni...