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Sample records for basolateral amygdaloid complex

  1. Exposure to an open-field arena increases c-Fos expression in a distributed anxiety-related system projecting to the basolateral amygdaloid complex

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    Hale, M.W.; Hay-Schmidt, A.; Mikkelsen, J.D.;

    2008-01-01

    Anxiety states and anxiety-related behaviors appear to be regulated by a distributed and highly interconnected system of brain structures including the basolateral amygdala. Our previous studies demonstrate that exposure of rats to an open-field in high- and low-light conditions results in a marked...... of specific afferent input to this region of the amygdala. In order to identify candidate brain regions mediating anxiety-induced activation of the basolateral amygdaloid complex in rats, we used cholera toxin B subunit (CTb) as a retrograde tracer to identify neurons with direct afferent projections...... amygdaloid complex. Rats were housed individually for 11 days after CTb injections and handled (HA) for 2 min each day. On the test day rats were either, 1) exposed to an open-field in low-light conditions (8-13 lux) for 15 min (OF); 2) briefly HA or 3) left undisturbed (control). We report that dual...

  2. Cortical inputs innervate calbindin-immunoreactive interneurons of the rat basolateral amygdaloid complex.

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    Unal, Gunes; Paré, Jean-Francois; Smith, Yoland; Paré, Denis

    2014-06-01

    The present study was undertaken to shed light on the synaptic organization of the rat basolateral amygdala (BLA). The BLA contains multiple types of GABAergic interneurons that are differentially connected with extrinsic afferents and other BLA cells. Previously, it was reported that parvalbumin immunoreactive (PV(+) ) interneurons receive strong excitatory inputs from principal BLA cells but very few cortical inputs, implying a prevalent role in feedback inhibition. However, because prior physiological studies indicate that cortical afferents do trigger feedforward inhibition in principal cells, the present study aimed to determine whether a numerically important subtype of interneurons, expressing calbindin (CB(+) ), receives cortical inputs. Rats received injections of the anterograde tracer Phaseolus vulgaris-leucoagglutinin (PHAL) in the perirhinal cortex or adjacent temporal neocortex. Light and electron microscopic observations of the relations between cortical inputs and BLA neurons were performed in the lateral (LA) and basolateral (BL) nuclei. Irrespective of the injection site (perirhinal or temporal neocortex) and target nucleus (LA or BL), ~90% of cortical axon terminals formed asymmetric synapses with dendritic spines of principal BLA neurons, while 10% contacted the dendritic shafts of presumed interneurons, half of which were CB(+) . Given the previously reported pattern of CB coexpression among GABAergic interneurons of the BLA, these results suggest that a subset of PV-immunonegative cells that express CB, most likely the somatostatin-positive interneurons, are important mediators of cortically evoked feedforward inhibition in the BLA.

  3. Nuclear organization of the rock hyrax (Procavia capensis) amygdaloid complex.

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    Limacher-Burrell, Aude-Marie; Bhagwandin, Adhil; Gravett, Nadine; Maseko, Busisiwe C; Manger, Paul R

    2016-07-01

    The current study details the nuclear organization of the rock hyrax amygdaloid complex using both Nissl and myelin stains, along with a range of immunohistochemical stains. The rock hyrax appears to be the least derived of the Afrotherians, a group with a huge range of body phenotypes, life histories and specialized behaviours, brain sizes, and ecological niches. In this sense, the rock hyrax represents a species where the organization of the amygdaloid complex may be reflective of that in stem Eutherian mammals. Our analysis indicates that the nuclear organization of the rock hyrax amygdaloid complex is indeed very similar to that in other mammals studied, with four major nuclear groupings (the deep or basolateral group; the superficial or cortical-like or corticomedial group; the centromedial group; and the other amygdaloid nuclei) being observed, which is typical of Eutherian mammals. Moreover, each of these groupings is composed of several nuclei, the vast majority of which were readily identified in the rock hyrax. Small nuclei identified in rodents and primates were absent in the superficial and centromedial groups, seemingly involved with olfaction. A novel shell-like nucleus of the accessory basal nuclear cluster was observed in the rock hyrax, again, likely to be involved in olfaction. The current study underlines the conserved nature of nuclear parcellation in the Eutherian mammal amygdaloid complex and indicates that across most species, the flow of information processing related to species-specific affective-laden stimuli and the resultant physiological and behavioural outcomes are likely to be similar across species.

  4. Enhancement of basolateral amygdaloid neuronal dendritic arborization following Bacopa monniera extract treatment in adult rats

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    Venkata Ramana Vollala

    2011-01-01

    Full Text Available OBJECTIVE: In the ancient Indian system of medicine, Ayurveda, Bacopa monniera is classified as Medhya rasayana, which includes medicinal plants that rejuvenate intellect and memory. Here, we investigated the effect of a standardized extract of Bacopa monniera on the dendritic morphology of neurons in the basolateral amygdala, a region that is concerned with learning and memory. METHODS: The present study was conducted on 2¹/2-month-old Wistar rats. The rats were divided into 2-, 4- and 6-week treatment groups. Rats in each of these groups were further divided into 20 mg/kg, 40 mg/kg and 80 mg/kg dose groups (n = 8 for each dose. After the treatment period, treated rats and age-matched control rats were subjected to spatial learning (T-maze and passive avoidance tests. Subsequently, these rats were killed by decapitation, the brains were removed, and the amygdaloid neurons were impregnated with silver nitrate (Golgi staining. Basolateral amygdaloid neurons were traced using camera lucida, and dendritic branching points (a measure of dendritic arborization and dendritic intersections (a measure of dendritic length were quantified. These data were compared with the data from the age-matched control rats. RESULTS: The results showed an improvement in spatial learning performance and enhanced memory retention in rats treated with Bacopa monniera extract. Furthermore, a significant increase in dendritic length and the number of dendritic branching points was observed along the length of the dendrites of the basolateral amygdaloid neurons of rats treated with 40 mg/kg and 80 mg/kg of Bacopa monniera (BM for longer periods of time (i.e., 4 and 6 weeks. CONCLUSION: We conclude that constituents present in Bacopa monniera extract have neuronal dendritic growth-stimulating properties.

  5. Serotonergic innervation and serotonin receptor expression of NPY-producing neurons in the rat lateral and basolateral amygdaloid nuclei.

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    Bonn, M; Schmitt, A; Lesch, K-P; Van Bockstaele, E J; Asan, E

    2013-03-01

    Pharmacobehavioral studies in experimental animals, and imaging studies in humans, indicate that serotonergic transmission in the amygdala plays a key role in emotional processing, especially for anxiety-related stimuli. The lateral and basolateral amygdaloid nuclei receive a dense serotonergic innervation in all species studied to date. We investigated interrelations between serotonergic afferents and neuropeptide Y (NPY)-producing neurons, which are a subpopulation of inhibitory interneurons in the rat lateral and basolateral nuclei with particularly strong anxiolytic properties. Dual light microscopic immunolabeling showed numerous appositions of serotonergic afferents on NPY-immunoreactive somata. Using electron microscopy, direct membrane appositions and synaptic contacts between serotonin-containing axon terminals and NPY-immunoreactive cellular profiles were unequivocally established. Double in situ hybridization documented that more than 50 %, and about 30-40 % of NPY mRNA-producing neurons, co-expressed inhibitory 5-HT1A and excitatory 5-HT2C mRNA receptor subtype mRNA, respectively, in both nuclei with no gender differences. Triple in situ hybridization showed that individual NPY mRNA-producing interneurons co-express both 5-HT1A and 5-HT2C mRNAs. Co-expression of NPY and 5-HT3 mRNA was not observed. The results demonstrate that serotonergic afferents provide substantial innervation of NPY-producing neurons in the rat lateral and basolateral amygdaloid nuclei. Studies of serotonin receptor subtype co-expression indicate a differential impact of the serotonergic innervation on this small, but important, population of anxiolytic interneurons, and provide the basis for future studies of the circuitry underlying serotonergic modulation of emotional stimulus processing in the amygdala.

  6. Stereological estimation of the number of neurons in the human amygdaloid complex.

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    Schumann, Cynthia Mills; Amaral, David G

    2005-10-31

    Pathological changes in neuronal density in the amygdaloid complex have been associated with various neurological disorders. However, due to variable shrinkage during tissue processing, the only way to determine changes in neuron number unambiguously is to estimate absolute counts, rather than neuronal density. As the first stage in evaluating potential neuropathology of the amygdala in autism, the total number of neurons was estimated in the control human amygdaloid complex by using stereological sampling. The intact amygdaloid complex from one hemisphere of 10 brains was frozen and sectioned. One 100-microm section was selected every 500 microm and stained by the standard Nissl method. The entire amygdaloid complex was outlined and then further partitioned into five reliably defined subdivisions: 1) the lateral nucleus, 2) the basal nucleus, 3) the accessory basal nucleus, 4) the central nucleus, and 5) the remaining nuclei (including anterior cortical, anterior amygdaloid area, periamygdaloid cortex, medial, posterior cortical, nucleus of the lateral olfactory tract, amygdalohippocampal area, and intercalated nuclei). The number of neurons was measured by using an optical fractionator with Stereoinvestigator software. The mean number of neurons (x 10(6)) for each region was as follows: lateral nucleus 4.00, basal nucleus 3.24, accessory basal nucleus 1.28, central nucleus 0.36, remaining nuclei 3.33, and total amygdaloid complex 12.21. The stereological assessment of neuron number in the human amygdala provides an essential baseline for comparison of patient populations, such as autism, in which the amygdala may develop abnormally. To facilitate these types of analyses, this paper provides a detailed anatomical description of the methods used to define subdivisions of the human amygdaloid complex.

  7. Distribution of GABA-like immunoreactivity in the rat amygdaloid complex.

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    Nitecka, L; Ben-Ari, Y

    1987-12-01

    The distribution of GABA-like (GABA-Li) immunoreactivity in the rat amygdaloid complex was studied by using an anti-GABA antibody. GABA-Li positive neurons and processes were present in every nucleus of the complex. Three patterns of immunoreactivity were revealed: (1) the intercalated masses and the lateral olfactory tract nucleus exhibited the most intense staining of the neuropil, and virtually every neuron was labeled, (2) the central and medial nuclei contained intensely labeled neuropil and moderately labeled neurons, and (3) in the remaining nuclei, the neuropil was weakly labeled, and relatively numerous GABA-Li neurons were present. Our results suggest that: (1) the intercalated masses and lateral olfactory tract nucleus consist of large aggregates of GABA-Li immunoreactive neurons, and (2) the lateral, basal dorsal, and the posterior cortical nuclei may constitute a significant source of GABAergic connections to other amygdaloid nuclei, in particular to the medial and central nuclei.

  8. Structural bases for neurophysiological investigations of amygdaloid complex of the brain

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    Kalimullina, Liliya B.; Kalkamanov, Kh. A.; Akhmadeev, Azat V.; Zakharov, Vadim P.; Sharafullin, Ildus F.

    2015-11-01

    Amygdala (Am) as a part of limbic system of the brain defines such important functions as adaptive behavior of animals, formation of emotions and memory, regulation of endocrine and visceral functions. We worked out, with the help of mathematic modelling of the pattern recognition theory, principles for organization of neurophysiological and neuromorphological studies of Am nuclei, which take into account the existing heterogeneity of its formations and optimize, to a great extent, the protocol for carrying out of such investigations. The given scheme of studies of Am’s structural-functional organization at its highly-informative sections can be used as a guide for precise placement of electrodes’, cannulae’s and microsensors into particular Am nucleus in the brain with the registration not only the nucleus itself, but also its extensions. This information is also important for defining the number of slices covering specific Am nuclei which must be investigated to reveal the physiological role of a particular part of amygdaloid complex.

  9. DBS in the baso-lateral amygdala improves symptoms of autism and related self-injurious behaviourA case report and hypothesis on the pathogenesis of the disorder

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    Volker eSturm

    2013-01-01

    Full Text Available We treated a thirteen year old boy for life-threatening self-injurious behavior (SIB and severe Kanner’s autism with Deep Brain Stimulation (DBS in the amygdaloid complex as well as in the supra-amygdaloid projection system. Two DBS-electrodes were placed in both structures of each hemisphere. The stimulation contacts targeted the paralaminar, the basolateral, the central amygdala as well as the supra-amygdaloid projection system. DBS was applied to each of these structures, but only stimulation of the baso-lateral part proved effective in improving SIB and core symptoms of the autism spectrum in the emotional, social and even cognitive domains over a follow up of now 24 months. These results, which have been gained for the first time in a patient, support hypotheses, according to which the amygdala may be pivotal in the pathogeneses of autism and point to the special relevance of the baso-lateral part.

  10. El complejo amigdalino humano y su implicación en los trastornos psiquiátricos The amygdaloid complex and its implication in psychiatric disorders

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    M. T. Ledo-Varela

    2007-04-01

    Full Text Available El complejo amigdalino es un conjunto de núcleos que se localizan en la profundidad del lóbulo temporal, y que guardan estrecha relación con el sistema límbico. Su alteración se ha asociado a un gran número de procesos psiquiátricos. En este artículo se pretende hacer una revisión de lo publicado en referencia a la implicación amigdalina en trastornos psiquiátricos comunes. En ellos se observa un complejo amigdalino alterado, siendo su máxima expresión el síndrome de Klüver-Bucy. En pacientes esquizofrénicos se ha observado una reducción del volumen amigdalino, bilateral en varones y unilateral en mujeres. Esto sugiere que las alteraciones morfométricas del complejo amigdalino están más extendidas en varones esquizofrénicos. El complejo amigdalino está aumentado en niños autistas, no siendo así en adolescentes, donde se iguala al volumen de cualquier adolescente o adulto sano. Sin embargo, estudios neuroanatómicos han demostrado patología microscópica. En los pacientes con trastornos en el estado de ánimo, se observa una cierta tendencia a presentar un complejo amigdalino izquierdo de menor volumen. El volumen amigdalino de los grupos con demencia frontotemporal y enfermedad de Alzheimer era diferente a los del grupo de control, y se ha visto una predisposición al incremento de la atrofia amigdalina. Se puede afirmar que el complejo amigdalino está implicado en numerosos procesos psiquiátricos, tanto por daño estructural de dicho complejo como por daño funcional. Sin embargo, hacen falta más estudios para delimitar la influencia real del complejo amigdalino en dichos trastornos.The amygdaloid complex is a group of nuclei located deep in the temporal lobe and closely involved in the limbic system. Its alteration has been associated with some psychiatric processes. In this article, an overall review was made of the published data concerning the amygdaloid complex in the most common psychiatric diseases. A damaged

  11. Involvement of the basolateral complex and central nucleus of amygdala in the omission effects of different magnitudes of reinforcement.

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    Judice-Daher, Danielle M; Tavares, Tatiane F; Bueno, José Lino O

    2012-07-15

    Evidence from appetitive Pavlovian and instrumental conditioning studies suggest that the amygdala is involved in modulation of responses correlated with motivational states, and therefore, to the modulation of processes probably underlying reinforcement omission effects. The present study aimed to clarify whether or not the mechanisms related to reinforcement omission effects of different magnitudes depend on basolateral complex and central nucleus of amygdala. Rats were trained on a fixed-interval 12s with limited hold 6s signaled schedule in which correct responses were always followed by one of two reinforcement magnitudes. Bilateral lesions of the basolateral complex and central nucleus were made after acquisition of stable performance. After postoperative recovery, the training was changed from 100% to 50% reinforcement schedules. The results showed that lesions of the basolateral complex and central nucleus did not eliminate or reduce, but interfere with reinforcement omission effects. The response from rats of both the basolateral complex and central nucleus lesioned group was higher relative to that of the rats of their respective sham-lesioned groups after reinforcement omission. Thus, the lesioned rats were more sensitive to the omission effect. Moreover, the basolateral complex lesions prevented the magnitude effect on reinforcement omission effects. Basolateral complex lesioned rats showed no differential performance following omission of larger and smaller reinforcement magnitude. Thus, the basolateral complex is involved in incentive processes relative to omission of different reinforcement magnitudes. Therefore, it is possible that reinforcement omission effects are modulated by brain circuitry which involves amygdala.

  12. Effects of voluntary wheeling exercise on the learning and memory and c-fos expression of basolateral amygdaloid nucleus of depression model rats%自愿转轮运动对抑郁模型大鼠学习记忆及基底外侧杏仁核c-fos表达的影响

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    崔建梅; 药宏慧; 李中华; 庞立杰; 贺继平

    2013-01-01

    探讨4周自愿转轮运动对慢性不可预知性应激致抑郁大鼠旷场行为及空间学习记忆能力、血清皮质醇和基底外侧杏仁核c-fos 表达的影响。将40只大鼠随机分为4组,即对照组、运动组、应激模型组及应激运动组,每组10只。应激模型组及应激运动组大鼠每日进行慢性不可预知性应激1次,连续28 d,同时运动组及应激运动组大鼠进行4周自愿转轮运动。自愿转轮运动结束后检测大鼠血清皮质醇水平;运用旷场实验测试大鼠自主活动能力及探索行为;八臂迷宫实验检测大鼠空间学习记忆能力;采用免疫组织化学结合图像半定量方法对基底外侧杏仁核 c-fos神经元的数量、面积及灰度进行测量和分析。结果发现:1)与应激模型组比较,应激运动组大鼠穿越格数、直立次数及修饰次数显著增多(P0.05)。以上结果说明,自愿转轮运动可提高抑郁大鼠的学习记忆能力,机理可能与长期自愿转轮运动降低抑郁大鼠的血清皮质醇水平及增强大脑基底外侧杏仁核c-fos 的表达有关。%In order to probe into the effects of 4-week voluntary wheeling exercise on the open field behavior, space learning and memorizing ability, blood serum cortisol and c-fos expression of basolateral amygdaloid nucleus of rats having depression caused by chronic and unpredictable stress, the authors divided 40 rats randomly into 4 groups:a control group, an exercise group, a stress model group and a stress exercise group, each of which included 10 rats, put the rats in the stress model group and stress exercise group under chronic and unpredictable stress once a day for consecutive 28 d, let the rats in the exercise group and stress exercise group do a voluntary wheeling exercise for 4 weeks, measured the level of blood serum cortisol of the rats after the voluntary wheeling exercise was completed, applied the open field experiment to test the

  13. Pharmacological depletion of serotonin in the basolateral amygdala complex reduces anxiety and disrupts fear conditioning.

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    Johnson, Philip L; Molosh, Andrei; Fitz, Stephanie D; Arendt, Dave; Deehan, Gerald A; Federici, Lauren M; Bernabe, Cristian; Engleman, Eric A; Rodd, Zachary A; Lowry, Christopher A; Shekhar, Anantha

    2015-11-01

    The basolateral and lateral amygdala nuclei complex (BLC) is implicated in a number of emotional responses including conditioned fear and social anxiety. Based on previous studies demonstrating that enhanced serotonin release in the BLC leads to increased anxiety and fear responses, we hypothesized that pharmacologically depleting serotonin in the BLC using 5,7-dihydroxytryptamine (5,7-DHT) injections would lead to diminished anxiety and disrupted fear conditioning. To test this hypothesis, 5,7-DHT(a serotonin-depleting agent) was bilaterally injected into the BLC. Desipramine (a norepinephrine reuptake inhibitor) was systemically administered to prevent non-selective effects on norepinephrine. After 5days, 5-7-DHT-treated rats showed increases in the duration of social interaction (SI) time, suggestive of reduced anxiety-like behavior. We then used a cue-induced fear conditioning protocol with shock as the unconditioned stimulus and tone as the conditioned stimulus for rats pretreated with bilateral 5,7-DHT, or vehicle, injections into the BLC. Compared to vehicle-treated rats, 5,7-DHT rats had reduced acquisition of fear during conditioning (measured by freezing time during tone), also had reduced fear retrieval/recall on subsequent testing days. Ex vivo analyses revealed that 5,7-DHT reduced local 5-HT concentrations in the BLC by ~40% without altering local norepinephrine or dopamine concentrations. These data provide additional support for 5-HT playing a critical role in modulating anxiety-like behavior and fear-associated memories through its actions within the BLC.

  14. Development of neurons and fibers containing calcium binding proteins in the pallial amygdala of mouse, with special emphasis on those of the basolateral amygdalar complex.

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    Legaz, Isabel; Olmos, Luis; Real, M Angeles; Guirado, Salvador; Dávila, José Carlos; Medina, Loreta

    2005-08-08

    We studied the development of neurons and fibers containing calbindin, calretinin, and parvalbumin in the mouse pallial amygdala, with special emphasis on those of the basolateral amygdalar complex. Numerous calbindin-immunoreactive (CB+) cells were observed in the incipient basolateral amygdalar complex and cortical amygdalar area from E13.5. At E16.5, CB+ cells became more abundant in the lateral and basolateral nuclei than in the basomedial nucleus, showing a pattern very similar to that of gamma-aminobutyric acid (GABA)ergic neurons. Many CB+ cells observed in the pallial amygdala appeared to originate in the anterior entopeduncular area/ganglionic eminences of the subpallium. The density of CB+ cells gradually increased in the pallial amygdala until the first postnatal week and appeared to decrease later, coinciding with the postnatal appearance of parvalbumin cells and raising the possibility of a partial phenotypic shift. Calretinin (CR) immunoreactivity could be observed in a few cells and fibers in the pallial amygdala at E14.5, and by E16.5 it became a good marker of the different nuclei of the basolateral amygdalar complex. Numerous CB+ and CR+ varicosities, part of which have an intrinsic origin, were observed in the basolateral amygdalar complex from E16.5, and some surrounded unstained perikarya and/or processes before birth, indicating an early formation of inhibitory networks. Each calcium binding protein showed a distinct spatiotemporal expression pattern of development in the mouse pallial amygdala. Any alteration in the development of neurons and fibers containing calcium binding proteins of the pallial amygdala may result in important disorders of emotional and social behavior.

  15. A Different Recruitment of the Lateral and Basolateral Amygdala Promotes Contextual or Elemental Conditioned Association in Pavlovian Fear Conditioning

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    Calandreau, Ludovic; Desmedt, Aline; Decorte, Laurence; Jaffard, Robert

    2005-01-01

    Convergent data suggest dissociated roles for the lateral (LA) and basolateral (BLA) amygdaloid nuclei in fear conditioning, depending on whether a discrete conditioned stimulus (CS)-unconditional stimulus (US) or context-US association is considered. Here, we show that pretraining inactivation of the BLA selectively impaired conditioning to…

  16. Injections of urocortin 1 into the basolateral amygdala induce anxiety-like behavior and c-Fos expression in brainstem serotonergic neurons.

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    Spiga, F; Lightman, S L; Shekhar, A; Lowry, C A

    2006-01-01

    The amygdala plays a key role in emotional processing and anxiety-related physiological and behavioral responses. Previous studies have shown that injections of the anxiety-related neuropeptide corticotropin-releasing factor or the related neuropeptide urocortin 1 into the region of the basolateral amygdaloid nucleus induce anxiety-like behavior in several behavioral paradigms. Brainstem serotonergic systems in the dorsal raphe nucleus and median raphe nucleus may be part of a distributed neural system that, together with the basolateral amygdala, regulates acute and chronic anxiety states. We therefore investigated the effect of an acute bilateral injection of urocortin 1 into the basolateral amygdala on behavior in the social interaction test and on c-Fos expression within serotonergic neurons in the dorsal raphe nucleus and median raphe nucleus. Male rats were implanted with bilateral cannulae directed at the region of the basolateral amygdala; 72 h after surgery, rats were injected with urocortin 1 (50 fmol/100 nl) or vehicle (100 nl of 1% bovine serum albumin in distilled water). Thirty minutes after injection, a subgroup of rats from each experimental group was exposed to the social interaction test; remaining animals were left in the home cage. Two hours after injection rats were perfused with paraformaldehyde and brains were removed and processed for immunohistochemistry. Acute injection of urocortin 1 had anxiogenic effects in the social interaction test, reducing total interaction time without affecting locomotor activity or exploratory behavior. These behavioral effects were associated with increases in c-Fos expression within brainstem serotonergic neurons. In home cage rats and rats exposed to the social interaction test, urocortin 1 treatment increased the number of c-Fos-immunoreactive serotonergic neurons within subdivisions of both the dorsal raphe nucleus and median raphe nucleus. These results are consistent with the hypothesis that the

  17. Basolateral amygdala lesion inhibits the development of pain chronicity in neuropathic pain rats.

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    Zheng Li

    Full Text Available BACKGROUND: Chronicity of pain is one of the most interesting questions in chronic pain study. Clinical and experimental data suggest that supraspinal areas responsible for negative emotions such as depression and anxiety contribute to the chronicity of pain. The amygdala is suspected to be a potential structure for the pain chronicity due to its critical role in processing negative emotions and pain information. OBJECTIVE: This study aimed to investigate whether amygdala or its subregions, the basolateral amygdala (BLA and the central medial amygdala (CeA, contributes to the pain chronicity in the spared nerve injury (SNI-induced neuropathic pain model of rats. METHODOLOGY/PRINCIPAL FINDINGS: (1 Before the establishment of the SNI-induced neuropathic pain model of rats, lesion of the amygdaloid complex with stereotaxic injection of ibotenic acid (IBO alleviated mechanical allodynia significantly at days 7 and 14, even no mechanical allodynia at day 28 after SNI; Lesion of the BLA, but not the CeA had similar effects; (2 however, 7 days after SNI when the neuropathic pain model was established, lesion of the amygdala complex or the BLA or the CeA, mechanical allodynia was not affected. CONCLUSION: These results suggest that BLA activities in the early stage after nerve injury might be crucial to the development of pain chronicity, and amygdala-related negative emotions and pain-related memories could promote pain chronicity.

  18. Amygdaloid lesions block the effect of neuropeptides (vasopressin, ACTH4–10) on avoidance behavior

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    Wimersma Greidanus, T.B. van; Croiset, G.; Bakker, E.; Bouman, H.

    1979-01-01

    Lesions in the amygdaloid complex result in an increased activity of rats in open field behavior in that generally more exploration and rearing is observed as compared with sham-operated animals. No effect of the lesion was observed on acquisition and extinction of an active avoidance response, but

  19. Exposure to an open-field arena increases c-Fos expression in a subpopulation of neurons in the dorsal raphe nucleus, including neurons projecting to the basolateral amygdaloid complex

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    Hale, M.W.; Hay-Schmidt, A.; Mikkelsen, J.D.;

    2008-01-01

    . Treatment effects on c-Fos expression in serotonergic and non-serotonergic cells in the midbrain raphe nuclei were determined 2 h following open-field exposure or home cage control (CO) conditions. Rats tested under both light conditions responded with increases in c-Fos expression in serotonergic neurons......Serotonergic systems in the dorsal raphe nucleus are thought to play an important role in the regulation of anxiety states. To investigate responses of neurons in the dorsal raphe nucleus to a mild anxiety-related stimulus, we exposed rats to an open-field, under low-light or high-light conditions...... within subdivisions of the midbrain raphe nuclei compared with CO rats. However, the total numbers of serotonergic neurons involved were small suggesting that exposure to the open-field may affect a subpopulation of serotonergic neurons. To determine if exposure to the open-field activates a subset...

  20. [Role of central histamine in amygdaloid kindled seizures].

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    Kamei, C; Okuma, C

    2001-05-01

    The role of central histamine in amygdaloid kindled seizures in rats was studied. Histamine content in the amygdala was significantly decreased after development of amygdaloid kindling. Intracerebroventricular (i.c.v.) injection of histamine resulted in inhibition of amygdaloid kindled seizures. The H1-agonists 2-methylhistamine and 2-thiazolylethylamine also inhibited amygdaloid kindled seizures. In addition, intraperitoneal (i.p.) injection of histidine and metoprine inhibited amygdaloid kindled seizures at doses that caused increases in histamine contents of the brain. H1-antagonists (diphenhydramine and chlorpheniramine) attenuated histamine- or histidine-induced inhibition of amygdaloid kindled seizures. Both i.c.v. and i.p. injections of H3-antagonists (thioperamide, AQ0145 and clobenpropit) resulted in a dose-related inhibition of amygdaloid kindled seizures. The effects of thioperamide and AQ0145 were inhibited by an H3-agonist (R)-alpha-methylhistamine and H1-antagonists. On the other hand, H2-antagonists showed no antagonistic effect. GABAmimetic drugs, diazepam, sodium valproate and muscimol potentiated the effect of clobenpropit. Bicuculline caused significant antagonism of the inhibition of amygdaloid kindled seizures induced by clobenpropit. These findings suggested that a histaminergic mechanism plays an important role in suppressing amygdaloid kindled seizures through histamine H1-receptors. In addition, an inhibition of amygdaloid kindled seizures induced by histamine is closely related with the action of GABA.

  1. Inactivation of neuronal function in the amygdaloid region reduces tail artery blood flow alerting responses in conscious rats.

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    Mohammed, M; Kulasekara, K; De Menezes, R C; Ootsuka, Y; Blessing, W W

    2013-01-03

    Few studies have investigated whether neuronal function in the amygdaloid complex is necessary for the occurrence of the cardiovascular response to natural (unconditioned) environmental threats. In the present investigation in conscious unrestrained Sprague-Dawley rats we inactivated neuronal function in the amygdaloid complex acutely (bilateral muscimol injections) or chronically (unilateral or bilateral ibotenic acid injections) and measured the effect on sudden falls in tail artery blood flow elicited by non-noxious salient stimuli (sympathetic cutaneous vasomotor alerting responses, SCVARs). After acute bilateral injection of vehicle (200nl Ringer's solution) the SCVAR index was 81 ± 2%, indicating that tail blood flow was reduced by 81% in response to the salient stimuli. After acute bilateral injection of muscimol (1 nmol in 200 nl of Ringer's solution) into the amygdaloid complex the SCVAR index was 49 ± 5%, indicating that tail blood flow was reduced by 49% in response to the salient stimuli (pbody with more immediate metabolic requirements.

  2. Morphometric characteristics of Neuropeptide Y immunoreactive neurons of human cortical amygdaloid nucleus

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    Mališ Miloš

    2008-01-01

    Full Text Available Introduction Cortical amygdaloid nucleus belongs to the corticomedial part of the amygdaloid complex. In this nucleus there are neurons that produce neuropetide Y. This peptide has important roles in sleeping, learning, memory, gastrointestinal regulation, anxiety, epilepsy, alcoholism and depression. Material and methods We investigated morphometric characteristics (numbers of primary dendrites, longer and shorter diameters of cell bodies and maximal radius of dendritic arborization of NPY immunoreactive neurons of human cortical amygdaloid nucleus on 6 male adult human brains, aged 46 to 77 years, by immunohistochemical avidin-biotin technique. Results Our investigation has shown that in this nucleus there is a moderate number of NPY immunoreactive neurons. 67% of found neurons were nonpyramidal, while 33% were pyramidal. Among the nonpyramidal neurons the dominant groups were multipolar neurons (41% - of which 25% were multipolar irregular, and 16% multipolar oval. Among the pyramidal neurons the dominant groups were the neurons with triangular shape of cell body (21%. All found NPY immunoreactive neurons (pyramidal and nonpyramidal altogether had intervals of values of numbers of primary dendrites 2 to 6, longer diameters of cell bodies 13 to 38 µm, shorter diameters of cell bodies 9 to 20 µm and maximal radius of dendritic arborization 50 to 340 µm. More than a half of investigated neurons (57% had 3 primary dendrites. Discussion and conclusion The other researchers did not find such percentage of pyramidal immunoreactive neurons in this amygdaloid nucleus. If we compare our results with the results of the ather researchers we can conclude that all pyramidal NPY immunoreactive neurons found in this human amygdaloid nucleus belong to the class I of neurons, and that all nonpyramidal NPY immunoreactive neurons belong to the class II of neurons described by other researchers. We suppose that all found pyramidal neurons were projectional.

  3. Involvement of central histamine in amygdaloid kindled seizures in rats.

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    Kamei, C

    2001-10-15

    The involvement of central histamine in amygdaloid kindled seizures in rats was investigated using histamine-related compounds. Histamine contents in the amygdala of electrical stimulation site was significantly decreased after development of amygdaloid kindling. Intracerebroventricular (i.c.v.) injection of histamine resulted in inhibition of amygdaloid kindled seizures. The H(1)-agonists 2-methylhistamine and 2-thiazolylethylamine also inhibited amygdaloid kindled seizures. In addition, intraperitoneal (i.p.) injection of histidine and metoprine inhibited amygdaloid kindled seizures at doses that caused increases in histamine contents of the brain. H(1)-antagonists (diphenhydramine and chlorpheniramine) attenuated histamine (i.c.v.)-induced inhibition of amygdaloid kindled seizures, however, no significant antagonism was observed with H(2)-antagonists (cimetidine, ranitidine or zolantidine). Intracerebroventricular injection of H(3)-antagonists (thioperamide and AQ 0145) resulted in a dose-related inhibition of amygdaloid kindled seizures. The same findings were observed when thioperamide and clobenpropit were injected i.p. The effects of thioperamide (i.p.) and AQ 0145 (i.p.) were inhibited by an H(3)-agonist [(R)-alpha-methylhistamine] and H(1)-antagonists (diphenhydramine and chlorpheniramine). On the other hand, H(2)-antagonists (cimetidine and ranitidine) showed no antagonistic effects. These findings suggested that a histaminergic mechanism plays an important role in suppressing amygdaloid kindled seizures through histamine H(1)-receptors.

  4. [The amygdaloid body of the brain: some topics for discussion and little-studied problems].

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    Akmaev, I G; Kalimullina, L B

    1995-01-01

    Features of functional morphology of the amygdaloid brain complex (ABC) are analyzed in a new light presenting the notion of the ABC as a nucleo-paleocortical structure. The analysis of the structural organization of ABC could imply the presence of phylogenetically differentiated parts: the ancient, the old and the new amygdala. The presentation carries original data on the morphometric and histophysiological studies under various experimental alterations of the endocrine system. A concept is developed of the existence of a rostrocaudal gradient in the expression of sex-dependent structural and functional features of the amygdaloid complex as a neuroendocrine brain centre. Provided is technical recommendation for use in biological studies of amygdaloid brain complex mathematical models based on the theory of image identification. An original technique has also been recommended for selective dissection of the ABC with its eventual removal from nonfixed brain, which allows studies to be made of the ABC neurophysiological and neurochemical properties on surviving slices. Evidence is adduced indicating involvement of the ABC in the process of the brain sex differentiation.

  5. Multiple anxiogenic drugs recruit a parvalbumin-containing subpopulation of GABAergic interneurons in the basolateral amygdala.

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    Hale, Matthew W; Johnson, Philip L; Westerman, Alex M; Abrams, Jolane K; Shekhar, Anantha; Lowry, Christopher A

    2010-10-01

    The basolateral amygdala is a nodal structure within a distributed and interconnected network that regulates anxiety states and anxiety-related behavior. Administration of multiple anxiogenic drugs increases cellular responses (i.e., increases c-Fos expression) in a subregion of the basolateral amygdala, but the neurochemical phenotypes of these cells are not known. The basolateral amygdala contains glutamatergic projection neurons and several populations of γ-aminobutyric acid-synthesizing (GABAergic) interneurons, including a population of parvalbumin (PV)-expressing GABAergic interneurons that co-express the excitatory 5-HT(2A) receptor. The role for these PV-expressing GABAergic interneurons in anxiety-states is unclear. In this experiment we examined the effects of multiple anxiogenic drugs including the 5-HT(2C/2A) receptor agonist m-chlorophenyl piperazine (mCPP), the adenosine receptor antagonist caffeine, the α(2)-adrenoreceptor antagonist yohimbine and the partial inverse agonist at the benzodiazepine allosteric site on the GABA(A) receptor, N-methyl-beta-carboline-3-carboxamide (FG-7142), on c-Fos expression in PV-immunoreactive (PV-ir) interneurons in subdivisions of the basolateral amygdala. All drugs with the exception of mCPP increased c-Fos expression in PV-ir neurons in the basolateral amygdaloid nucleus, anterior part (BLA). The numbers of c-Fos-immunoreactive (c-Fos-ir)/PV-ir GABAergic interneurons in the BLA were positively correlated with the numbers of c-Fos-ir serotonergic neurons in the mid-rostrocaudal dorsal raphe nucleus (DR) and with a measure of anxiety-related behavior. All four drugs increased c-Fos expression in non-PV-ir cells in most of the subdivisions of the basolateral amygdala that were sampled, compared with vehicle-injected controls. Together, these data suggest that the PV/5-HT(2A) receptor expressing GABAergic interneurons in the basolateral amygdala are part of a DR-basolateral amygdala neuronal circuit modulating

  6. Effect of dipotassium clorazepate on amygdaloid-kindling and comparison between amygdaloid- and hippocampal-kindled seizures in rats.

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    Amano, K; Takamatsu, J; Ogata, A; Katsuragi, S; Miyazaki, C; Deshimaru, M; Sumiyoshi, S; Miyakawa, T

    1999-12-03

    We examined the effect of dipotassium clorazepate (7-chloro-1, 3-dihydro-2-oxo-5-phenyl-1H-1, 4-benzodiazepine-3-carboxylate potassium hydroxide), an antianxiety drug, on amygdaloid kindling and compared its effects for 7 successive days on amygdaloid- versus hippocampal-kindled seizures, using the rat kindling model of epilepsy. Dipotassium clorazepate at 5 mg/kg significantly delayed amygdaloid kindling. The contralateral cortical after-discharge duration in the dipotassium clorazepate-treated group was significantly shorter than the after-discharge duration in the amygdala in the first seven stimulations, whereas it was significantly shorter only in the first three stimulations in the control group, indicating that dipotassium clorazepate suppressed the spread of seizure activity from focus to contralateral cortex. Dipotassium clorazepate suppressed amygdaloid-kindled seizures at 2 and 5 mg/kg, while 1 mg/kg or more suppressed hippocampal-kindled seizures. Thus, differences in effective dosages in both amygdaloid- and hippocampal-kindled seizures may suggest a difference in the neuronal mechanisms involved in this kindling.

  7. Morphologic Study of Superior Temporal Sulcus-Amygdaloid Body and Lateral Fissure-Amygdaloid Body Surgical Approach by Using Magnetic Resonance Imaging Volume Rendering.

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    Qu, Yuan; Ren, Bichen; Chang, Xiaoyu; Zhang, Jinnan; Li, Youqiong; Duan, Haobo; Cheng, Kailiang; Wang, Jincheng

    2016-01-01

    In this research, 83 patients were measured by magnetic resonance imaging volume rendering technique. The authors acquired the curve length of the superior temporal sulcus and the lateral fissure on the cerebral hemisphere, the shortest distance from the superior temporal sulcus and the lateral fissure to the center of amygdaloid body separately, the vertical diameter, the transversal diameter, and the anteroposterior diameter of the amygdaloid body and the 2 approach angles between the median sagittal plane and the shortest segment from the superior temporal sulcus to the center of amygdaloid body and the shortest segment from lateral fissure to the center of the amygdaloid body. At the same time, we preliminarily oriented the 2 points of the superior temporal sulcus and the lateral fissure, which are closest to the center of amygdaloid body, aimed at finding out the best entrance points of surgical approach through the superior temporal sulcus and the lateral fissure to the amygdaloid body and reducing the damage to the nerve fibers or blood vessels during the operation. The results indicate that the point at the front side 1/4 of the superior temporal sulcus may be the ideal surgical approach entrance point and the point at the front side 1/3 of the lateral fissure. There is no difference between 2 cerebral hemispheres (P < 0.05).

  8. Descending effect on spinal nociception by amygdaloid glutamate varies with the submodality of noxious test stimulation.

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    Bourbia, Nora; Sagalajev, Boriss; Pertovaara, Antti

    2014-06-06

    Amygdala has an important role in the processing of primary emotions, such as fear. Additionally, amygdala is involved in processing and modulation of pain. While the amygdala, particularly its central nucleus (CeA), has been shown to contribute to pain control, the descending pain regulation by the CeA is still only partly characterized. Here heat and mechanical nociception was tested in both hind limbs of healthy rats with a chronic guide cannula for microinjection of glutamate into the CeA of the left or right hemisphere. The aim was to assess whether the descending pain regulatory effect by glutamate in the amygdala varies with the submodality or the body side of nociceptive testing, brain hemisphere or the amygdaloid glutamate receptor. Motor performance was assessed with the Rotarod test. Amygdaloid glutamate, independent of the treated hemisphere, produced a dose-related heat and mechanical antinociception that varied with the submodality of testing. Heat antinociception was short lasting (minutes), bilateral and not reversed by blocking the amygdaloid NMDA receptor with MK-801. In contrast, mechanical antinociception lasted longer (>20 min), was predominantly contralateral and reversed by blocking the amygdaloid NMDA receptor. At an antinociceptive dose, amygdaloid glutamate failed to influence motor performance. The results indicate that independent of the brain hemisphere, the spatial extent and duration of the descending antinociceptive effect induced by amygdaloid glutamate varies with the amygdaloid glutamate receptor and the submodality of pain.

  9. Endocannabinoids in the rat basolateral amygdala enhance memory consolidation and enable glucocorticoid modulation of memory

    NARCIS (Netherlands)

    Campolongo, Patrizia; Roozendaal, Benno; Trezza, Viviana; Hauer, Daniela; Schelling, Gustav; McGaugh, James L.; Cuomo, Vincenzo

    2009-01-01

    Extensive evidence indicates that the basolateral complex of the amygdala (BLA) modulates the consolidation of memories for emotionally arousing experiences, an effect that involves the activation of the glucocorticoid system. Because the BLA expresses high densities of cannabinoid CB1 receptors, th

  10. Amygdaloid projections to the ventral striatum in mice: Direct and indirect chemosensory inputs to the brain reward system

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    Amparo eNovejarque

    2011-08-01

    Full Text Available Rodents constitute good models for studying the neural basis of socio-sexual behaviour. Recent findings in mice have revealed the molecular identity of the some pheromonal molecules triggering intersexual attraction. However, the neural pathways mediating this basic socio-sexual behaviour remain elusive. Since previous work indicates that the dopaminergic tegmento-striatal pathway is not involved in pheromone reward, the present report explores alternative pathways linking the vomeronasal system with the tegmento-striatal system (the limbic basal ganglia by means of tract-tracing experiments studying direct and indirect projections from the chemosensory amygdala to the ventral striato-pallidum. Amygdaloid projections to the nucleus accumbens, olfactory tubercle and adjoining structures are studied by analysing the retrograde transport in the amygdala from dextranamine and fluorogold injections in the ventral striatum, as well as the anterograde labelling found in the ventral striato-pallidum after dextranamine injections in the amgydala. This combination of anterograde and retrograde tracing experiments reveals direct projections from the vomeronasal cortex to the ventral striato-pallidum, as well as indirect projections through different nuclei of the basolateral amygdala. Direct projections innervate mainly the olfactory tubercle and the islands of Calleja, whereas indirect projections are more widespread and reach the same structures and the shell and core of nucleus accumbens. These pathways are likely to mediate innate responses to pheromones (direct projections and conditioned responses to associated chemosensory and non-chemosensory stimuli (indirect projections. Comparative studies indicate that similar connections are present in all the studied amniote vertebrates and might constitute the basic circuitry for emotional responses to conspecifics in most vertebrates, including humans.

  11. Projections from the central amygdaloid nucleus to the precuneiform nucleus in the mouse.

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    Liang, Huazheng; Watson, Charles; Paxinos, George

    2015-01-01

    The mouse precuneiform nucleus has been proposed as the midbrain locomotion center, a function ascribed to its caudal neighbor, cuneiform nucleus, in the rat, cat and other species. The present study investigated the projections from the central amygdaloid nucleus to the precuneiform nucleus in the mouse using retrograde tracer injections (fluoro-gold) into the precuneiform nucleus and anterograde tracer injections (biotinylated dextran amine) into the central amygdaloid nucleus. The entire central amygdaloid nucleus except the rostral pole had retrogradely labeled neurons, especially in the middle portion where labeled neurons were densely packed. Anterogradely labeled amygdaloid fibers approached the precuneiform nucleus from the area ventrolateral to it and terminated in the entire precuneiform nucleus. Labeled fibers were also found in laminae 5 and 6 in the upper cervical cord on the ipsilateral side. The present study is the first demonstration of projections from the central amygdaloid nucleus to the precuneiform nucleus. This projection may underpin the role of the precuneiform nucleus in the modulation of the cardiovascular activity.

  12. Effects of clobazam on amygdaloid and hippocampal kindled seizures in rats.

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    Ichimaru, Y; Gomita, Y; Moriyama, M

    1987-05-01

    The effect of clobazam, a 1,5-benzodiazepine, on kindling seizures was compared with the effects of 1,4-benzodiazepines, diazepam and bromazepam, in amygdaloid and hippocampal kindled rats. After kindled seizures were established (stage 5 seizure), the test drugs were administered intraperitoneally. In amygdaloid kindled rats, clobazam significantly suppressed the motor seizures (MS) at doses of 20 and 50 mg/kg and significantly shortened the duration of after-discharge (AD) at doses of 10 to 50 mg/kg. Diazepam at doses of 2 to 10 mg/kg and bromazepam at 1 to 5 mg/kg also significantly suppressed the MS and significantly shortened the duration of AD. Similar suppressive effects by these three benzodiazepines were observed in hippocampal kindled rats. From these results, clobazam was found to have a qualitatively similar but weaker anticonvulsive effect than those of 1,4-benzodiazepines.

  13. Involvement of BDNF signaling transmission from basolateral amygdala to infralimbic prefrontal cortex in conditioned taste aversion extinction.

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    Xin, Jian; Ma, Ling; Zhang, Tian-Yi; Yu, Hui; Wang, Yue; Kong, Liang; Chen, Zhe-Yu

    2014-05-21

    Brain-derived neurotrophic factor (BDNF) and its receptor, tropomyosin-related kinase receptor B (TrkB), play a critical role in memory extinction. However, the detailed role of BDNF in memory extinction on the basis of neural circuit has not been fully understood. Here, we aim to investigate the role of BDNF signaling circuit in mediating conditioned taste aversion (CTA) memory extinction of the rats. We found region-specific changes in BDNF gene expression during CTA extinction. CTA extinction led to increased BDNF gene expression in the basolateral amygdala (BLA) and infralimbic prefrontal cortex (IL) but not in the central amygdaloid nucleus (CeA) and hippocampus (HIP). Moreover, blocking BDNF signaling or exogenous microinjection of BDNF into the BLA or IL could disrupt or enhance CTA extinction, which suggested that BDNF signaling in the BLA and IL is necessary and sufficient for CTA extinction. Interestingly, we found that microinjection of BDNF-neutralizing antibody into the BLA could abolish the extinction training-induced BDNF mRNA level increase in the IL, but not vice versa, demonstrating that BDNF signaling is transmitted from the BLA to IL during extinction. Finally, the accelerated extinction learning by infusion of exogenous BDNF in the BLA could also be blocked by IL infusion of BDNF-neutralizing antibody rather than vice versa, indicating that the IL, but not BLA, is the primary action site of BDNF in CTA extinction. Together, these data suggest that BLA-IL circuit regulates CTA memory extinction by identifying BDNF as a key regulator.

  14. The Role of the Basolateral Amygdala in Punishment

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    Dit-Bressel, Philip Jean-Richard; McNally, Gavan P.

    2015-01-01

    Aversive stimuli not only support fear conditioning to their environmental antecedents, they also punish behaviors that cause their occurrence. The amygdala, especially the basolateral nucleus (BLA), has been critically implicated in Pavlovian fear learning but its role in punishment remains poorly understood. Here, we used a within-subjects…

  15. NMDA receptors in the basolateral amygdala and gustatory neophobia.

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    Figueroa-Guzmán, Yazmín; Reilly, Steve

    2008-05-19

    The attenuation of gustatory neophobia occurs during repeated exposures to an initially novel taste solution that is increasingly perceived as safe and familiar. The present study examined whether NMDA receptors in the basolateral region of the amygdala (BLA) are involved in this important behavioral phenomenon. The results, which show that the attenuation, but not initial occurrence, of gustatory neophobia is dependent upon NMDA receptors in the BLA, are discussed with reference to a similar finding involving NMDA receptors in the insular cortex.

  16. Mesencephalic basolateral domain specification is dependent on Sonic Hedgehog

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    Jesus E. Martinez-Lopez

    2015-02-01

    Full Text Available In the study of central nervous system morphogenesis, the identification of new molecular markers allows us to identify domains along the antero-posterior and dorso-ventral axes. In the past years, the alar and basal plates of the midbrain have been divided into different domains. The precise location of the alar-basal boundary is still under discussion. We have identified Barhl1, Nhlh1 and Six3 as appropriate molecular markers to the adjacent domains of this transition. The description of their expression patterns and the contribution to the different mesencephalic populations corroborated their role in the specification of these domains. We studied the influence of Sonic Hedgehog on these markers and therefore on the specification of these territories. The lack of this morphogen produced severe alterations in the expression pattern of Barhl1 and Nhlh1 with consequent misspecification of the basolateral domain. Six3 expression was apparently unaffected, however its distribution changed leading to altered basal domains. In this study we confirmed the localization of the alar-basal boundary dorsal to the basolateral domain and demonstrated that the development of the basolateral domain highly depends on Shh.

  17. Basolateral Cl- uptake mechanisms in Xenopus laevis lung epithelium.

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    Berger, Jens; Hardt, Martin; Clauss, Wolfgang G; Fronius, Martin

    2010-07-01

    A thin liquid layer covers the lungs of air-breathing vertebrates. Active ion transport processes via the pulmonary epithelial cells regulate the maintenance of this layer. This study focuses on basolateral Cl(-) uptake mechanisms in native lungs of Xenopus laevis and the involvement of the Na(+)/K(+)/2 Cl(-) cotransporter (NKCC) and HCO(3)(-)/Cl(-) anion exchanger (AE), in particular. Western blot analysis and immunofluorescence staining revealed the expression of the NKCC protein in the Xenopus lung. Ussing chamber experiments demonstrated that the NKCC inhibitors (bumetanide and furosemide) were ineffective at blocking the cotransporter under basal conditions, as well as under pharmacologically stimulated Cl(-)-secreting conditions (forskolin and chlorzoxazone application). However, functional evidence for the NKCC was detected by generating a transepithelial Cl(-) gradient. Further, we were interested in the involvement of the HCO(3)(-)/Cl(-) anion exchanger to transepithelial ion transport processes. Basolateral application of DIDS, an inhibitor of the AE, resulted in a significantly decreased the short-circuit current (I(SC)). The effect of DIDS was diminished by acetazolamide and reduced by increased external HCO(3)(-) concentrations. Cl(-) secretion induced by forskolin was decreased by DIDS, but this effect was abolished in the presence of HCO(3)(-). These experiments indicate that the AE at least partially contributes to Cl(-) secretion. Taken together, our data show that in Xenopus lung epithelia, the AE, rather than the NKCC, is involved in basolateral Cl(-) uptake, which contrasts with the common model for Cl(-) secretion in pulmonary epithelia.

  18. Effects of estrogen treatment on expression of brain-derived neurotrophic factor and cAMP response element-binding protein expression and phosphorylation in rat amygdaloid and hippocampal structures.

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    Zhou, Jin; Zhang, Huaibo; Cohen, Rochelle S; Pandey, Subhash C

    2005-01-01

    Clinical studies indicate an effect of estrogen (E2) on affect and cognition, which may be mediated by the cAMP response element-binding protein (CREB) pathway and CREB-related gene target brain-derived neurotrophic factor (BDNF). We investigated the effect of E2 on CREB expression and phosphorylation and BDNF expression in the amygdala and hippocampus, areas involved in emotional processing. Ovariectomized rats were given 10 microg 17beta-estradiol or vehicle for 14 days and expression of components of the CREB signaling pathway, i.e., CREB, phosphorylated CREB (pCREB), and BDNF in amygdala and hippocampus were investigated using immunogold labeling. Levels of BDNF mRNA were determined by in situ reverse-transcriptase polymerase chain reaction. We also examined the effect of E2 on calcium/calmodulin kinase (CaMK IV) immunolabeling in the hippocampus. E2 increased immunolabeling and mRNA levels of BDNF in the medial and basomedial amygdala and CA1 and CA3 regions of the hippocampus, but not in any other amygdaloid or hippocampal regions examined. E2 increased immunolabeling of CREB and pCREB in the medial and basomedial, but not central or basolateral amygdala. E2 also increased CaMK IV and pCREB immunolabeling in the CA1 and CA3 regions, but not CA2 region or dentate gyrus, of the hippocampus. There was no change in immunolabeling of CREB in any hippocampal region. These data identify a signaling pathway through which E2 increases BDNF expression that may underlie some actions of E2 on affective behavior and indicate neuroanatomical heterogeneity in the E2 effect within the amygdala and hippocampus.

  19. Distribution of Prestin on Outer Hair Cell Basolateral Surface

    Institute of Scientific and Technical Information of China (English)

    YU Ning; ZHAI Suo-qiang; YANG Shi-ming; HAN Dong-yi; ZHAO Hong-bo

    2008-01-01

    Prestin has been identified as a motor protein responsible for outer hair cell (OHC) electromotility and is expressed on the OHC surface. Previous studies revealed that OHC eleetromotility and its associated nonlinear capacitance were mainly located at the OHC lateral wall and absent at the apical cutieular plate and the basal nucleus region. Immunofluorescent staining for prestin also failed to demonstrate prestin expression at the OHC basal ends in whole-mount preparation of the organ of Corti. However, there lacks a definitive demonstration of the pattern of prestin distribution. The OHC lateral wall has a trilaminate organization and is composed of the plasma membrane, cortical lattice, and subsurface cisternae. In this study, the location of prestin proteins in dissociated OHCs was examined using immunofluorescent staining and confocal microscopy. We found that prestin was uniformly expressed on the basolateral surface, including the basal pole. No staining was seen on the cuticular plate and stereocilia. When co-stained with a membrane marker di-8-ANEPPS, prestin-labeling was found to be in the outer layer of the OHC lateral wall. After separating the plasma membrane from the underlying subsurface eisternae using a hypotonic extracellular solution, prestin-labeling was found to be in the plasma membrane, not the subsurface cisternae. The data show that prestin is expressed in the plasma membrane on the entire OHC basolateral surface.

  20. Severe stress hormone conditions cause an extended window of excitability in the mouse basolateral amygdala

    NARCIS (Netherlands)

    Karst, Henk; Joëls, Marian

    2016-01-01

    Shortly after stress, basolateral amygdala neurons are exposed to sequential yet partly overlapping waves of hormones. We examined how these hormonal waves can change activity of basolateral amygdala neurons such that emotional aspects of stress become so deeply ingrained. To this end, spontaneous g

  1. Differences between the tolerance characteristics of two anticonvulsant benzodiazepines in the amygdaloid-kindled rat.

    Science.gov (United States)

    Amano, K; Katsuragi, S; Takamatsu, J; Ogata, A; Miyazaki, C; Deshimaru, M; Miyakawa, T

    2001-07-20

    The characteristics of the development of tolerance to the anticonvulsant effects of chronic treatment by dipotassium clorazepate and diazepam using amygdaloid-kindled rats were investigated. Dipotassium clorazepate (5 mg/kg) or diazepam (5 mg/kg) were intraperitoneally administered for 10 consecutive days. Tolerance to the anticonvulsant effect of dipotassium clorazepate developed in seizure stage on day 6, after-discharge duration on day 7 and seizure latency on day 4. In contrast, tolerance to the effects of diazepam developed more rapidly in seizure stage on day 4, after-discharge duration on day 4 and seizure latency on day 3. Thus tolerance to the anticonvulsive effect of dipotassium clorazepate developed relatively slower than that to diazepam. All rats had stage 5 convulsions 24 hr after cessation of the administration of dipotassium clorazepate and diazepam. Concomitant determinations of plasma concentrations of the main metabolite of dipotassium clorazepate and diazepam, desmethyldiazepam, showed no statistical difference during treatment, suggesting that the developed tolerance was not metabolic but functional.

  2. Synaptic vesicle protein2A decreases in amygdaloid-kindling pharmcoresistant epileptic rats.

    Science.gov (United States)

    Shi, Jing; Zhou, Feng; Wang, Li-kun; Wu, Guo-feng

    2015-10-01

    Synaptic vesicle protein 2A (SV2A) involvement has been reported in the animal models of epilepsy and in human intractable epilepsy. The difference between pharmacosensitive epilepsy and pharmacoresistant epilepsy remains poorly understood. The present study aimed to observe the hippocampus SV2A protein expression in amygdale-kindling pharmacoresistant epileptic rats. The pharmacosensitive epileptic rats served as control. Amygdaloid-kindling model of epilepsy was established in 100 healthy adult male Sprague-Dawley rats. The kindled rat model of epilepsy was used to select pharmacoresistance by testing their seizure response to phenytoin and phenobarbital. The selected pharmacoresistant rats were assigned to a pharmacoresistant epileptic group (PRE group). Another 12 pharmacosensitive epileptic rats (PSE group) served as control. Immunohistochemistry, real-time PCR and Western blotting were used to determine SV2A expression in the hippocampus tissue samples from both the PRE and the PSE rats. Immunohistochemistry staining showed that SV2A was mainly accumulated in the cytoplasm of the neurons, as well as along their dendrites throughout all subfields of the hippocampus. Immunoreactive staining level of SV2A-positive cells was 0.483 ± 0.304 in the PRE group and 0.866 ± 0.090 in the PSE group (P kindling rats.

  3. Paradoxical facilitation of working memory after basolateral amygdala damage.

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    Barak Morgan

    Full Text Available Working memory is a vital cognitive capacity without which meaningful thinking and logical reasoning would be impossible. Working memory is integrally dependent upon prefrontal cortex and it has been suggested that voluntary control of working memory, enabling sustained emotion inhibition, was the crucial step in the evolution of modern humans. Consistent with this, recent fMRI studies suggest that working memory performance depends upon the capacity of prefrontal cortex to suppress bottom-up amygdala signals during emotional arousal. However fMRI is not well-suited to definitively resolve questions of causality. Moreover, the amygdala is neither structurally or functionally homogenous and fMRI studies do not resolve which amygdala sub-regions interfere with working memory. Lesion studies on the other hand can contribute unique causal evidence on aspects of brain-behaviour phenomena fMRI cannot "see". To address these questions we investigated working memory performance in three adult female subjects with bilateral basolateral amygdala calcification consequent to Urbach-Wiethe Disease and ten healthy controls. Amygdala lesion extent and functionality was determined by structural and functional MRI methods. Working memory performance was assessed using the Wechsler Adult Intelligence Scale-III digit span forward task. State and trait anxiety measures to control for possible emotional differences between patient and control groups were administered. Structural MRI showed bilateral selective basolateral amygdala damage in the three Urbach-Wiethe Disease subjects and fMRI confirmed intact functionality in the remaining amygdala sub-regions. The three Urbach-Wiethe Disease subjects showed significant working memory facilitation relative to controls. Control measures showed no group anxiety differences. Results are provisionally interpreted in terms of a 'cooperation through competition' networks model that may account for the observed paradoxical

  4. Differential expression of Kv3.1b and Kv3.2 potassium channel subunits in interneurons of the basolateral amygdala.

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    McDonald, A J; Mascagni, F

    2006-01-01

    The expression of Kv3.1 and Kv3.2 voltage-gated potassium channel subunits appears to be critical for high-frequency firing of many neuronal populations. In the cortex these subunits are mainly associated with fast-firing GABAergic interneurons containing parvalbumin or somatostatin. Since the basolateral nuclear complex of the amygdala contains similar interneurons, it is of interest to determine if these potassium channel subunits are expressed in these same interneuronal subpopulations. To investigate this issue, peroxidase and dual-labeling fluorescence immunohistochemistry combined with confocal laser scanning microscopy was used to determine which interneuronal subpopulations in the basolateral nuclear complex of the rat amygdala express Kv3.1b and Kv3.2 subunits. Antibodies to parvalbumin, somatostatin, calretinin, and cholecystokinin were used to label separate subsets of basolateral amygdalar interneurons. Examination of immunoperoxidase preparations suggested that the expression of both channels was restricted to nonpyramidal interneurons in the basolateral amygdala. Somata and proximal dendrites were intensely-stained, and axon terminals arising from presumptive basket cells and chandelier cells were lightly stained. Immunofluorescence observations revealed that parvalbumin+ neurons were the main interneuronal subpopulation expressing the Kv3.1b potassium channel subunit in the basolateral amygdala. More than 92-96% of parvalbumin+ neurons were Kv3.1b+, depending on the nucleus. These parvalbumin+/Kv3.1b+ double-labeled cells constituted 90-99% of all Kv3.1b+ neurons. Parvalbumin+ neurons were also the main interneuronal subpopulation expressing the Kv3.2 potassium channel subunit. More than 67-78% of parvalbumin+ neurons were Kv3.2+, depending on the nucleus. However, these parvalbumin+/Kv3.2+ double-labeled cells constituted only 71-81% of all Kv3.2+ neurons. Most of the remaining neurons with significant levels of the Kv3.2 subunit were somatostatin

  5. Unilateral low-frequency stimulation of central piriform cortex delays seizure development induced by amygdaloid kindling in rats.

    Science.gov (United States)

    Yang, L-X; Jin, C-L; Zhu-Ge, Z-B; Wang, S; Wei, E-Q; Bruce, I C; Chen, Z

    2006-01-01

    Low-frequency stimulation of the kindling site interferes with the course of kindling epileptogenesis. The present study examined the effect of unilateral low-frequency stimulation of the central piriform cortex on seizure development induced by amygdaloid kindling in rats. The ipsilateral or contralateral central piriform cortex received low-frequency stimulation (15 min train of 0.1 ms pulses at 1 Hz and 50-150 muA) immediately after termination of once daily kindling stimulation (2 s train of 1 ms pulses at 60 Hz and 150-300 microA) in the right amygdala for 30 days. Low-frequency stimulation of either the ipsilateral or contralateral central piriform cortex significantly suppressed the progression of seizure stages and reduced afterdischarge duration throughout the course of amygdaloid kindling. The marked suppression induced by low-frequency stimulation of the central piriform cortex on either side was predominantly due to the significant retardation of progression from stage 0 to stage 1 and stage 3 to stage 4 seizures. In addition, the suppressive effect of low-frequency stimulation did not disappear when the stimulation was stopped; it could persist for at least 10 days. These findings indicate that brain areas other than the kindling focus, such as the central piriform cortex on both sides, can also be used as reasonable targets for low-frequency stimulation to retard seizure development induced by amygdaloid kindling. Secondly, like the ipsilateral central piriform cortex, the contralateral central piriform cortex may also participate in the progression and secondary generalization of focal seizures. The study suggests that unilateral low-frequency stimulation of the central piriform cortex may have a significant antiepileptogenic effect, and may be helpful for exploring effective and long-lasting therapies for human temporal lobe epilepsy.

  6. Consecutive 15 min is necessary for focal low frequency stimulation to inhibit amygdaloid-kindling seizures in rats.

    Science.gov (United States)

    Liu, Yang; Wang, Yi; Xu, Zhenghao; Xu, Cenglin; Ying, Xiaoying; Wang, Shuang; Zhang, Shihong; Xiao, Bo; Chen, Zhong

    2013-09-01

    Low-frequency stimulation (LFS) is emerging as a new option for the treatment of intractable epilepsy. The stimulation duration may influence the anti-epileptic effect of LFS but is poorly studied. The present study was designed to evaluate the anti-epileptic effect of focal LFS with different stimulation duration on amygdaloid-kindling seizures in rats. We found 15 and 30 min but not 1 or 5 min LFS delivered immediately after the kindling stimulation slowed the progression of behavioral seizure stages and reduced mean afterdischarge duration (ADD) during kindling acquisition. In fully kindled animals, 15 and 30min rather than 1 and 5 min LFS decreased the incidence of generalized seizures and the average seizure stage as well as shortened the cumulative generalized seizure duration (GSD). Meanwhile, EEG analysis showed 15 and 30 min LFS specifically lowered the power in delta band. However, if 15min LFS delivered intermittently by 5 min interval, it had no suppressing effect on kindling rat. Thus, it is likely that consecutive 15 min is necessary for LFS to inhibit amygdaloid-kindling seizures in rats, indicating the stimulation duration may be a key fact affecting the clinical effect of LFS on epilepsy.

  7. The basolateral amygdala in reward learning and addiction.

    Science.gov (United States)

    Wassum, Kate M; Izquierdo, Alicia

    2015-10-01

    Sophisticated behavioral paradigms partnered with the emergence of increasingly selective techniques to target the basolateral amygdala (BLA) have resulted in an enhanced understanding of the role of this nucleus in learning and using reward information. Due to the wide variety of behavioral approaches many questions remain on the circumscribed role of BLA in appetitive behavior. In this review, we integrate conclusions of BLA function in reward-related behavior using traditional interference techniques (lesion, pharmacological inactivation) with those using newer methodological approaches in experimental animals that allow in vivo manipulation of cell type-specific populations and neural recordings. Secondly, from a review of appetitive behavioral tasks in rodents and monkeys and recent computational models of reward procurement, we derive evidence for BLA as a neural integrator of reward value, history, and cost parameters. Taken together, BLA codes specific and temporally dynamic outcome representations in a distributed network to orchestrate adaptive responses. We provide evidence that experiences with opiates and psychostimulants alter these outcome representations in BLA, resulting in long-term modified action.

  8. The basolateral amygdala in reward learning and addiction

    Science.gov (United States)

    Wassum, Kate M.; Izquierdo, Alicia

    2015-01-01

    Sophisticated behavioral paradigms partnered with the emergence of increasingly selective techniques to target the basolateral amygdala (BLA) have resulted in an enhanced understanding of the role of this nucleus in learning and using reward information. Due to the wide variety of behavioral approaches many questions remain on the circumscribed role of BLA in appetitive behavior. In this review, we integrate conclusions of BLA function in reward-related behavior using traditional interference techniques (lesion, pharmacological inactivation) with those using newer methodological approaches in experimental animals that allow in vivo manipulation of cell type-specific populations and neural recordings. Secondly, from a review of appetitive behavioral tasks in rodents and monkeys and recent computational models of reward procurement, we derive evidence for BLA as a neural integrator of reward value, history, and cost parameters. Taken together, BLA codes specific and temporally dynamic outcome representations in a distributed network to orchestrate adaptive responses. We provide evidence that experiences with opiates and psychostimulants alter these outcome representations in BLA, resulting in long-term modified action. PMID:26341938

  9. Endocannabinoid Signaling within the Basolateral Amygdala Integrates Multiple Stress Hormone Effects on Memory Consolidation

    Science.gov (United States)

    Atsak, Piray; Hauer, Daniela; Campolongo, Patrizia; Schelling, Gustav; Fornari, Raquel V; Roozendaal, Benno

    2015-01-01

    Glucocorticoid hormones are known to act synergistically with other stress-activated neuromodulatory systems, such as norepinephrine and corticotropin-releasing factor (CRF), within the basolateral complex of the amygdala (BLA) to induce optimal strengthening of the consolidation of long-term memory of emotionally arousing experiences. However, as the onset of these glucocorticoid actions appear often too rapid to be explained by genomic regulation, the neurobiological mechanism of how glucocorticoids could modify the memory-enhancing properties of norepinephrine and CRF remained elusive. Here, we show that the endocannabinoid system, a rapidly activated retrograde messenger system, is a primary route mediating the actions of glucocorticoids, via a glucocorticoid receptor on the cell surface, on BLA neural plasticity and memory consolidation. Furthermore, glucocorticoids recruit downstream endocannabinoid activity within the BLA to interact with both the norepinephrine and CRF systems in enhancing memory consolidation. These findings have important implications for understanding the fine-tuned crosstalk between multiple stress hormone systems in the coordination of (mal)adaptive stress and emotional arousal effects on neural plasticity and memory consolidation. PMID:25547713

  10. Impact of basal forebrain cholinergic inputs on basolateral amygdala neurons.

    Science.gov (United States)

    Unal, Cagri T; Pare, Denis; Zaborszky, Laszlo

    2015-01-14

    In addition to innervating the cerebral cortex, basal forebrain cholinergic (BFc) neurons send a dense projection to the basolateral nucleus of the amygdala (BLA). In this study, we investigated the effect of near physiological acetylcholine release on BLA neurons using optogenetic tools and in vitro patch-clamp recordings. Adult transgenic mice expressing cre-recombinase under the choline acetyltransferase promoter were used to selectively transduce BFc neurons with channelrhodopsin-2 and a reporter through the injection of an adeno-associated virus. Light-induced stimulation of BFc axons produced different effects depending on the BLA cell type. In late-firing interneurons, BFc inputs elicited fast nicotinic EPSPs. In contrast, no response could be detected in fast-spiking interneurons. In principal BLA neurons, two different effects were elicited depending on their activity level. When principal BLA neurons were quiescent or made to fire at low rates by depolarizing current injection, light-induced activation of BFc axons elicited muscarinic IPSPs. In contrast, with stronger depolarizing currents, eliciting firing above ∼ 6-8 Hz, these muscarinic IPSPs lost their efficacy because stimulation of BFc inputs prolonged current-evoked afterdepolarizations. All the effects observed in principal neurons were dependent on muscarinic receptors type 1, engaging different intracellular mechanisms in a state-dependent manner. Overall, our results suggest that acetylcholine enhances the signal-to-noise ratio in principal BLA neurons. Moreover, the cholinergic engagement of afterdepolarizations may contribute to the formation of stimulus associations during fear-conditioning tasks where the timing of conditioned and unconditioned stimuli is not optimal for the induction of synaptic plasticity.

  11. Characterization of basolateral chloride/bicarbonate exchange in macula densa cells.

    Science.gov (United States)

    Komlosi, Peter; Frische, Sebastian; Fuson, Amanda L; Fintha, Attila; Zsembery, Akos; Peti-Peterdi, Janos; Bell, P Darwin

    2005-02-01

    Functional and immunohistological studies were performed to identify basolateral chloride/bicarbonate exchange in macula densa cells. Using the isolated, perfused thick ascending limb with attached glomerulus preparation dissected from rabbit kidney, macula densa intracellular pH (pH(i)) was measured with fluorescence microscopy and BCECF. For these experiments, basolateral chloride was reduced, resulting in reversible macula densa cell alkalinization. Anion exchange activity was assessed by measuring the maximal net base efflux on readdition of bath chloride. Anion exchange activity required the presence of bicarbonate, was independent of changes in membrane potential, did not require the presence of sodium, and was inhibited by high concentrations of DIDS. Inhibition of macula densa anion exchange activity by basolateral DIDS increased luminal NaCl concentration-induced elevations in pH(i). Immunohistochemical studies using antibodies against AE2 demonstrated expression of AE2 along the basolateral membrane of macula densa cells of rabbit kidney. These results suggest that macula densa cells functionally and immunologically express a chloride/bicarbonate exchanger at the basolateral membrane. This transporter likely participates in the regulation of pH(i) and might be involved in macula densa signaling.

  12. Corticosterone induced morphological changes of hippocampal and amygdaloid cell lines are dependent on 5-HT7 receptor related signal pathway.

    Science.gov (United States)

    Xu, Y; Zhang, C; Wang, R; Govindarajan, S S; Barish, P A; Vernon, M M; Fu, C; Acharya, A P; Chen, L; Boykin, E; Yu, J; Pan, J; O'Donnell, J M; Ogle, W O

    2011-05-19

    Stress is an unavoidable life experience. It induces mood, cognitive dysfunction and plasticity changes in chronically stressed individuals. Among the various brain regions that have been studied, the hippocampus and amygdala have been observed to have different roles in controlling the limbic-hypothalamic-pituitary-adrenal axis (limbic-HPA axis). This study investigated how the stress hormone corticosterone (CORT) affects neuronal cells. The first aim is to test whether administration of CORT to hippocampal and amygdaloid cell lines induces different changes in the 5-HT receptor subtypes. The second goal is to determine whether stress induced morphological changes in these two cell lines were involved in the 5-HT receptor subtypes expression. We now show that 5-HT(7) receptor mRNA levels were significantly upregulated in HT-22 cells, but downregulated in AR-5 cells by exposure to a physiologically relevant level of CORT (50 μM) for 24 h, which was later confirmed by primary hippocampal and amygdaloid neuron cultures. Additionally, pretreatment of cells with 5-HT(7) antagonist SB-269970 or agonist LP-44 reversed CORT induced cell lesion in a dose-dependent manner. Moreover, CORT induced different changes in neurite length, number of neurites and soma size in HT-22 and AR-5 cells were also reversed by pretreatment with either SB-269970 or LP-44. The different effects of 5-HT(7) receptors on cell lines were observed in two members of the Rho family small GTPase expression: the Cdc-42 and RhoA. These observed results support the hypothesis that 5-HT may differentially modulate neuronal morphology in the hippocampus and amygdala depending on the expression levels of the 5-HT receptor subtypes during stress hormone insults.

  13. Iron repletion relocalizes hephaestin to a proximal basolateral compartment in polarized MDCK and Caco2 cells

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Seung-Min [Department of Biological Sciences, University of Columbia, NY (United States); Department of Nutritional Science and Toxicology, University of California, Berkeley, CA (United States); Attieh, Zouhair K. [Department of Laboratory Science and Technology, American University of Science and Technology, Ashrafieh (Lebanon); Department of Nutritional Science and Toxicology, University of California, Berkeley, CA (United States); Son, Hee Sook [Department of Food Science and Human Nutrition, College of Human Ecology, Chonbuk National University (Korea, Republic of); Department of Nutritional Science and Toxicology, University of California, Berkeley, CA (United States); Chen, Huijun [Medical School, Nanjing University, Nanjing 210008, Jiangsu Province (China); Department of Nutritional Science and Toxicology, University of California, Berkeley, CA (United States); Bacouri-Haidar, Mhenia [Department of Biology, Faculty of Sciences (I), Lebanese University, Hadath (Lebanon); Department of Nutritional Science and Toxicology, University of California, Berkeley, CA (United States); Vulpe, Chris D., E-mail: vulpe@berkeley.edu [Department of Nutritional Science and Toxicology, University of California, Berkeley, CA (United States)

    2012-05-11

    Highlights: Black-Right-Pointing-Pointer Hephaestin localizes in the perinuclear space in non-polarized cells. Black-Right-Pointing-Pointer Hephaestin localizes in the perinuclear space in iron deficient and polarized cells. Black-Right-Pointing-Pointer Hephaestin with apical iron moves near to basolateral membrane of polarized cells. Black-Right-Pointing-Pointer Peri-basolateral location of hephaestin is accessible to the extracellular space. Black-Right-Pointing-Pointer Hephaestin is involved in iron mobilization from the intestine to circulation. -- Abstract: While intestinal cellular iron entry in vertebrates employs multiple routes including heme and non-heme routes, iron egress from these cells is exclusively channeled through the only known transporter, ferroportin. Reduced intestinal iron export in sex-linked anemia mice implicates hephaestin, a ferroxidase, in this process. Polarized cells are exposed to two distinct environments. Enterocytes contact the gut lumen via the apical surface of the cell, and through the basolateral surface, to the body. Previous studies indicate both local and systemic control of iron uptake. We hypothesized that differences in iron availability at the apical and/or basolateral surface may modulate iron uptake via cellular localization of hephaestin. We therefore characterized the localization of hephaestin in two models of polarized epithelial cell lines, MDCK and Caco2, with varying iron availability at the apical and basolateral surfaces. Our results indicate that hephaestin is expressed in a supra-nuclear compartment in non-polarized cells regardless of the iron status of the cells and in iron deficient and polarized cells. In polarized cells, we found that both apical (as FeSO{sub 4}) and basolateral iron (as the ratio of apo-transferrin to holo-transferrin) affect mobilization of hephaestin from the supra-nuclear compartment. We find that the presence of apical iron is essential for relocalization of hephaestin to a

  14. Basolateral potassium channels of rabbit colon epithelium: role in sodium absorption and chloride secretion.

    Science.gov (United States)

    Turnheim, Klaus; Plass, Herbert; Wyskovsky, Wolfgang

    2002-02-18

    In order to assess the role of different classes of K(+) channels in recirculation of K(+) across the basolateral membrane of rabbit distal colon epithelium, the effects of various K(+) channel inhibitors were tested on the activity of single K(+) channels from the basolateral membrane, on macroscopic basolateral K(+) conductance, and on the rate of Na(+) absorption and Cl(-) secretion. In single-channel measurements using the lipid bilayer reconstitution system, high-conductance (236 pS), Ca(2+)-activated K(+) (BK(Ca)) channels were most frequently detected; the second most abundant channel was a low-conductance K(+) channel (31 pS) that exhibited channel rundown. In addition to Ba(2+) and charybdotoxin (ChTX), the BK(Ca) channels were inhibited by quinidine, verapamil and tetraethylammonium (TEA), the latter only when present on the side of the channel from which K(+) flow originates. Macroscopic basolateral K(+) conductance, determined in amphotericin-permeabilised epithelia, was also markedly reduced by quinidine and verapamil, TEA inhibited only from the lumen side, and serosal ChTX was without effect. The chromanol 293B and the sulphonylurea tolbutamide did not affect BK(Ca) channels and had no or only a small inhibitory effect on macroscopic basolateral K(+) conductance. Transepithelial Na(+) absorption was partly inhibited by Ba(2+), quinidine and verapamil, suggesting that BK(Ca) channels are involved in basolateral recirculation of K(+) during Na(+) absorption in rabbit colon. The BK(Ca) channel inhibitors TEA and ChTX did not reduce Na(+) absorption, probably because TEA does not enter intact cells and ChTX is 'knocked off' its extracellular binding site by K(+) outflow from the cell interior. Transepithelial Cl(-) secretion was inhibited completely by Ba(2+) and 293B, partly by quinidine but not by the other K(+) channel blockers, indicating that the small (<3 pS) K(V)LQT1 channels are responsible for basolateral K(+) exit during Cl(-) secretion. Hence

  15. Variation in mouse basolateral amygdala volume is associated with differences in stress reactivity and fear learning.

    Science.gov (United States)

    Yang, Rebecca J; Mozhui, Khyobeni; Karlsson, Rose-Marie; Cameron, Heather A; Williams, Robert W; Holmes, Andrew

    2008-10-01

    A wealth of research identifies the amygdala as a key brain region mediating negative affect, and implicates amygdala dysfunction in the pathophysiology of anxiety disorders. Although there is a strong genetic component to anxiety disorders such as posttraumatic stress disorder (PTSD) there remains debate about whether abnormalities in amygdala function predispose to these disorders. In the present study, groups of C57BL/6 x DBA/2 (B x D) recombinant inbred strains of mice were selected for differences in volume of the basolateral amygdala complex (BLA). Strains with relatively small, medium, or large BLA volumes were compared for Pavlovian fear learning and memory, anxiety-related behaviors, depression-related behavior, and glucocorticoid responses to stress. Strains with relatively small BLA exhibited stronger conditioned fear responses to both auditory tone and contextual stimuli, as compared to groups with larger BLA. The small BLA group also showed significantly greater corticosterone responses to stress than the larger BLA groups. BLA volume did not predict clear differences in measures of anxiety-like behavior or depression-related behavior, other than greater locomotor inhibition to novelty in strains with smaller BLA. Neither striatal, hippocampal nor cerebellar volumes correlated significantly with any behavioral measure. The present data demonstrate a phenotype of enhanced fear conditioning and exaggerated glucocorticoid responses to stress associated with small BLA volume. This profile is reminiscent of the increased fear processing and stress reactivity that is associated with amygdala excitability and reduced amygdala volume in humans carrying loss of function polymorphisms in the serotonin transporter and monoamine oxidase A genes. Our study provides a unique example of how natural variation in amygdala volume associates with specific fear- and stress-related phenotypes in rodents, and further supports the role of amygdala dysfunction in anxiety

  16. Blockade of glutamatergic transmission in the primate basolateral amygdala suppresses active behavior without altering social interaction.

    Science.gov (United States)

    Forcelli, Patrick A; Wellman, Laurie L; Malkova, Ludise

    2017-04-01

    The amygdala is an integrator of affective processing, and a key component of a network regulating social behavior. While decades of lesion studies in nonhuman primates have shown alterations in social interactions after amygdala damage, acute manipulations of the amygdala in primates have been underexplored. We recently reported (Wellman, Forcelli, Aguilar, & Malkova, 2016) that acute pharmacological inhibition of the basolateral complex of the amygdala (BLA) or the central nucleus of the amygdala increased affiliative social interactions in experimental dyads of macaques; this was achieved through microinjection of a GABA-A receptor agonist. Prior studies in rodents have shown similar effects achieved by blocking NMDA receptors or AMPA receptors within the BLA. Here, we sought to determine the role of these receptor systems in the primate BLA in the context of social behavior. In familiar dyads, we microinjected the NMDA receptor antagonist 2-amino-7-phosphonoheptanoic acid (AP7) or the AMPA receptor antagonist 2,3-dioxo-6-nitro-1,2,3,4-tetrahydrobenzo[f]quinoxaline-7-sulfonamide (NBQX) and observed behaviors and social interactions in the immediate postinjection period. In striking contrast with our prior report using GABA agonists, and in contrast with prior reports in rodents using glutamate antagonists, we found that neither NMDA nor AMPA blockade increase social interaction. Both treatments, however, were associated with decreases in locomotion and manipulation and increases in passive behavior. These data suggest that local blockade of glutamatergic neurotransmission in BLA is not the functional equivalent of local activation of GABAergic signaling, and raise interesting questions regarding the functional microcircuitry of the nonhuman primate amygdala in the context of social behavior. (PsycINFO Database Record

  17. Glutamate Receptor Antagonist Infusions into the Basolateral and Medial Amygdala Reveal Differential Contributions to Olfactory vs. Context Fear Conditioning and Expression

    Science.gov (United States)

    Walker, David L.; Paschall, Gayla Y.; Davis, Michael

    2005-01-01

    The basolateral amygdala's involvement in fear acquisition and expression to visual and auditory stimuli is well known. The involvement of the basolateral and other amygdala areas in fear acquisition and expression to stimuli of other modalities is less certain. We evaluated the contribution of the basolateral and medial amygdala to olfactory and…

  18. Cortisol-sensitive urea transport across the gill basolateral membrane of the gulf toadfish (Opsanus beta).

    Science.gov (United States)

    Rodela, Tamara M; Gilmour, Kathleen M; Walsh, Patrick J; McDonald, M Danielle

    2009-08-01

    Gulf toadfish (Opsanus beta) use a unique pulsatile urea excretion mechanism that allows urea to be voided in large pulses via the periodic insertion or activation of a branchial urea transporter. The precise cellular and subcellular location of the facilitated diffusion mechanism(s) remains unclear. An in vitro basolateral membrane vesicle (BLMV) preparation was used to test the hypothesis that urea movement across the gill basolateral membrane occurs through a cortisol-sensitive carrier-mediated mechanism. Toadfish BLMVs demonstrated two components of urea uptake: a linear element at high external urea concentrations, and a phloretin-sensitive saturable constituent (K(m) = 0.24 mmol/l; V(max) = 6.95 micromol x mg protein(-1) x h(-1)) at low urea concentrations ( 2, further suggestive of carrier-mediated processes. Our data provide evidence that a basolateral urea facilitated transporter accelerates the movement of urea between the plasma and gills to enable the pulsatile excretion of urea. Furthermore, in vivo infusion of cortisol caused a significant 4.3-fold reduction in BLMV urea transport capacity in lab-crowded fish, suggesting that cortisol inhibits the recruitment of urea transporters to the basolateral membrane, which may ultimately affect the size of the urea pulse event in gulf toadfish.

  19. Basolateral Cl- channels in the larval bullfrog skin epithelium

    DEFF Research Database (Denmark)

    Hillyard, Stanley D.; Rios, K.; Larsen, Erik Hviid

    2002-01-01

    The addition of 150 U/ml nystatin to the mucosal surface of isolated skin from larval bullfrogs increases apical membrane permeability and allows a voltage clamp to be applied to the basolateral membrane. With identical Ringer's solutions bathing either side of the tissue the short-circuit curren...

  20. C-fos protein expression in the anterior amygdaloid area and nc. accumbens in the hypoxic rat brain

    Directory of Open Access Journals (Sweden)

    Babović Siniša S.

    2014-01-01

    Full Text Available Introduction. By examining the production of c-Fos protein, we analyzed the response to the ischemic attack in different brain tissue, two of which are regions of the limbic system: the anterior amygdaloid area and nc. accumbens. Material and Methods. We used the model of rat brain ischemia - four-vessel occlusion, and Pulsinelli’s method. The rats were treated in two ways, according to which they were divided into two groups: a total ischemia (ligation of four blood vessels, i.e. electrocauterization of the vertebral artery with bilateral ligation of the carotid artery - the so-called R-group rats, and transient ischemic attack (ligation of four blood vessels, i.e. electrocauterization of the vertebral artery, with mutual re-ligation of the carotid arteries in the form of transient ischemia - the so-called T-group rats, which can also be called “pre-conditioned group”. Both groups had their own control group. Conclusion. We have concluded that parts of the brain with an important role for the survival have a strong expression of c-fos gene.

  1. Long-term aldosterone treatment induces decreased apical but increased basolateral expression of AQP2 in CCD of rat kidney

    DEFF Research Database (Denmark)

    de Seigneux, Sophie; Nielsen, Jakob; Olesen, Emma T B;

    2007-01-01

    of hypokalemia in aldosterone-treated rats, we studied dietary-induced hypokalemia in rats, which also reduced apical AQP2 expression in the CCD but did not induce any increase in basolateral AQP2 expression in the CCD as observed with aldosterone treatment. The aldosterone-induced basolateral AQP2 expression...... in the CCD was thus independent of hypokalemia but was dependent on the presence of sodium and aldosterone. This redistribution was clearly blocked by mineralocorticoid receptor blockade. The increased basolateral expression of AQP2 induced by aldosterone may play a significant role in water metabolism...... in conditions with increased sodium reabsorption in the CCD....

  2. Electrophysiological study of transport systems in isolated perfused pancreatic ducts: properties of the basolateral membrane

    DEFF Research Database (Denmark)

    Novak, I; Greger, R

    1988-01-01

    In order to study the mechanism of pancreatic HCO3- transport, a perfused preparation of isolated intra- and interlobular ducts (i.d. 20-40 microns) of rat pancreas was developed. Responses of the epithelium to changes in the bath ionic concentration and to addition of transport inhibitors...... was monitored by electrophysiological techniques. In this report some properties of the basolateral membrane of pancreatic duct cells are described. The transepithelial potential difference (PDte) in ducts bathed in HCO3(-)-free and HCO3(-)-containing solution was -0.8 and -2.6 mV, respectively. The equivalent...... short circuit current (Isc) under similar conditions was 26 and 50 microA . cm-2. The specific transepithelial resistance (Rte) was 88 omega cm2. In control solutions the PD across the basolateral membrane (PDbl) was -63 +/- 1 mV (n = 314). Ouabain (3 mmol/l) depolarized PDbl by 4.8 +/- 1.1 mV (n = 6...

  3. Clathrin and AP1B: Key roles in basolateral trafficking through trans-endosomal routes

    Science.gov (United States)

    Gonzalez, Alfonso; Rodriguez-Boulan, Enrique

    2013-01-01

    Research following introduction of the MDCK model system to study epithelial polarity (1978) led to an initial paradigm that posited independent roles of the trans Golgi network (TGN) and recycling endosomes (RE) in the generation of, respectively, biosynthetic and recycling routes of plasma membrane (PM) proteins to apical and basolateral PM domains. This model dominated the field for 20 years. However, studies over the past decade and the discovery of the involvement of clathrin and clathrin adaptors in protein trafficking to the basolateral PM has led to a new paradigm. TGN and RE are now believed to cooperate closely in both biosynthetic and recycling trafficking routes. Here, we critically review these recent advances and the questions that remain unanswered. PMID:19854182

  4. Post-training depletions of basolateral amygdala serotonin fail to disrupt discrimination, retention, or reversal learning

    OpenAIRE

    G. Jesus eOchoa; Alexandra eStolyarova; Amandeep eKaur; Evan eHart; Amador eBugarin; Alicia eIzquierdo

    2015-01-01

    In goal-directed pursuits, the basolateral amygdala (BLA) is critical in learning about changes in the value of rewards. BLA-lesioned rats show enhanced reversal learning, a task employed to measure the flexibility of response to changes in reward. Similarly, there is a trend for enhanced discrimination learning, suggesting that BLA may modulate formation of stimulus-reward associations. There is a parallel literature on the importance of serotonin (5HT) in new stimulus-reward and reversal le...

  5. Excitatory amino acid receptors in the basolateral amygdala regulate anxiety responses in the social interaction test.

    Science.gov (United States)

    Sajdyk, T J; Shekhar, A

    1997-08-01

    Blocking GABA(A) receptors in the basolateral amygdala (BLA) elicits increases in heart rate (HR), blood pressure (BP) and anxiety responses by enhancing a glutamate mediated excitation. The present study was conducted to determine the role of the ionotropic glutamate receptors within the BLA in regulating HR, BP and experimental anxiety. Blocking basal glutamate excitation had no significant effect on HR or BP, but did elicit a significant anxiolytic-like effect.

  6. Active and passive Na+ fluxes across the basolateral membrane of rabbit urinary bladder.

    Science.gov (United States)

    Eaton, D C; Frace, A M; Silverthorn, S U

    1982-01-01

    The apical membrane of rabbit urinary bladder can be functionally removed by application of nystatin at high concentration if the mucosal surface of the tissue is bathed in a saline which mimics intracellular ion concentrations. Under these conditions, the tissue is as far as the movement of univalent ions no more than a sheet of basolateral membrane with some tight junctional membrane in parallel. In this manner the Na+ concentration at the inner surface of the basolateral membrane can be varied by altering the concentration in the mucosal bulk solution. When this was done both mucosal-to-serosal 22Na flux and net change in basolateral current were measured. The flux and the current could be further divided into the components of each that were either blocked by ouabain or insensitive to ouabain. Ouabain-insensitive mucosal-to-serosal Na+ flux was a linear function of mucosal Na+ concentration. Ouabain-sensitive Na+ flux and ouabain-sensitive, Na+-induced current both display a saturating relationship which cannot be accounted for by the presence of unstirred layers. If the interaction of Na+ with the basolateral transport process is assumed to involve the interaction of some number of Na+ ions, n, with a maximal flux, MMAX, then the data can be fit by assuming 3.2 equivalent sites for interaction and a value for MMAX of 287.8 pM cm-2 sec-1 with an intracellular Na concentration of 2.0 mM Na+ at half-maximal saturation. By comparing these values with the ouabain-sensitive, Na+-induced current, we calculate a Na+ to K+ coupling ratio of 1.40 +/- 0.07 for the transport process.

  7. Short environmental enrichment in adulthood reverses anxiety and basolateral amygdala hypertrophy induced by maternal separation.

    Science.gov (United States)

    Koe, A S; Ashokan, A; Mitra, R

    2016-02-02

    Maternal separation during early childhood results in greater sensitivity to stressors later in adult life. This is reflected as greater propensity to develop stress-related disorders in humans and animal models, including anxiety and depression. Environmental enrichment (EE) reverses some of the damaging effects of maternal separation in rodent models when provided during peripubescent life, temporally proximal to the separation. It is presently unknown if EE provided outside this critical window can still rescue separation-induced anxiety and neural plasticity. In this report we use a rat model to demonstrate that a single short episode of EE in adulthood reduced anxiety-like behaviour in maternally separated rats. We further show that maternal separation resulted in hypertrophy of dendrites and increase in spine density of basolateral amygdala neurons in adulthood, long after initial stress treatment. This is congruent with prior observations showing centrality of basolateral amygdala hypertrophy in anxiety induced by stress during adulthood. In line with the ability of the adult enrichment to rescue stress-induced anxiety, we show that enrichment renormalized stress-induced structural expansion of the amygdala neurons. These observations argue that behavioural plasticity induced by early adversity can be rescued by environmental interventions much later in life, likely mediated by ameliorating effects of enrichment on basolateral amygdala plasticity.

  8. β-Adrenergic activation enhances NMDA-induced current in pyramidal cells of the basolateral nucleus of amygdala

    Institute of Scientific and Technical Information of China (English)

    LIU Xinqiu; CAO Xiaohua; LI Bao-ming

    2005-01-01

    NMDA receptor (NMDA-R) in the amygdala complex is critical for both long-term potentiation (LTP) and formation of conditioned fear memory. It is reported that activation of β-adrenoceptors (β-AR) in the amygdala facilitates LTP and enhances memory consolidation. The present study examined the regulatory effect of β-AR activation on NMDA-R mediated current in pyramidal cells of the basolateral nucleus of amygdala (BLA), using whole-cell recording technique. Bath application of the β-AR agonist isoproterenol enhanced NMDA-induced current, and this facilitatory effect was blocked by co-administered propranolol, a β-AR antagonist. The facilitatory effect of isoproterenol on NMDA-induced current could not be induced when the protein kinase A (PKA) inhibitor Rp-cAMPs was added in electrode internal solution.The present results suggest that β-AR activation in the BLA could modulate NMDA-R activity directly and positively, probably via PKA.

  9. Acquisition of contextual Pavlovian fear conditioning is blocked by application of an NMDA receptor antagonist D,L-2-amino-5-phosphonovaleric acid to the basolateral amygdala.

    Science.gov (United States)

    Fanselow, M S; Kim, J J

    1994-02-01

    Rats, with chronic cannula placed bilaterally in the amygdala, received infusions of the N-methyl-D-aspartate (NMDA) receptor antagonist D,L-2-amino-5-phosphonovaleric acid (APV) before contextual Pavlovian fear conditioning. Administration of APV to the basolateral nucleus prevented acquisition of fear. Central nucleus infusions had no effect. It is concluded that an NMDA-mediated process near the basolateral region of the amygdala (e.g., lateral or basolateral nucleus) is essential for the learning of fear.

  10. Bioactive dietary polyphenols decrease heme iron absorption by decreasing basolateral iron release in human intestinal Caco-2 cells.

    Science.gov (United States)

    Ma, Qianyi; Kim, Eun-Young; Han, Okhee

    2010-06-01

    Because dietary polyphenolic compounds have a wide range of effects in vivo and vitro, including chelation of metals such as iron, it is prudent to test whether the regular consumption of dietary bioactive polyphenols impair the utilization of dietary iron. Because our previous study showed the inhibitory effect of (-) -epigallocatechin-3-gallate (EGCG) and grape seed extract (GSE) on nonheme iron absorption, we investigated whether EGCG and GSE also affect iron absorption from heme. The fully differentiated intestinal Caco-2 cells grown on microporous membrane inserts were incubated with heme (55)Fe in uptake buffer containing EGCG or GSE in the apical compartment for 7 h. Both EGCG and GSE decreased (P heme-derived iron. However, apical heme iron uptake was increased (P heme (55)Fe, the transfer of iron across the intestinal basolateral membrane was extremely low, indicating that basolateral export was impaired by GSE. In contrast, EGCG moderately decreased the cellular assimilation of heme (55)Fe, but the basolateral iron transfer was extremely low, suggesting that the basolateral efflux of heme iron was also inhibited by EGCG. Expression of heme oxygenase, ferroportin, and hephaestin protein was not changed by EGCG and GSE. The apical uptake of heme iron was temperature dependent and saturable in fully differentiated Caco-2 cells. Our data show that bioactive dietary polyphenols inhibit heme iron absorption mainly by reducing basolateral iron exit rather than decreasing apical heme iron uptake in intestinal cells.

  11. Basolateral Mg2+ extrusion via CNNM4 mediates transcellular Mg2+ transport across epithelia: a mouse model.

    Directory of Open Access Journals (Sweden)

    Daisuke Yamazaki

    Full Text Available Transcellular Mg(2+ transport across epithelia, involving both apical entry and basolateral extrusion, is essential for magnesium homeostasis, but molecules involved in basolateral extrusion have not yet been identified. Here, we show that CNNM4 is the basolaterally located Mg(2+ extrusion molecule. CNNM4 is strongly expressed in intestinal epithelia and localizes to their basolateral membrane. CNNM4-knockout mice showed hypomagnesemia due to the intestinal malabsorption of magnesium, suggesting its role in Mg(2+ extrusion to the inner parts of body. Imaging analyses revealed that CNNM4 can extrude Mg(2+ by exchanging intracellular Mg(2+ with extracellular Na(+. Furthermore, CNNM4 mutations cause Jalili syndrome, characterized by recessive amelogenesis imperfecta with cone-rod dystrophy. CNNM4-knockout mice showed defective amelogenesis, and CNNM4 again localizes to the basolateral membrane of ameloblasts, the enamel-forming epithelial cells. Missense point mutations associated with the disease abolish the Mg(2+ extrusion activity. These results demonstrate the crucial importance of Mg(2+ extrusion by CNNM4 in organismal and topical regulation of magnesium.

  12. Development and physiology of GABAergic feedback excitation in parvalbumin expressing interneurons of the mouse basolateral amygdala

    OpenAIRE

    Spampanato, Jay; Sullivan, Robert K. P.; Perumal, Madhusoothanan B.; Sah, Pankaj

    2016-01-01

    Abstract We have previously shown that in the basolateral amygdala (BLA), action potentials in one type of parvalbumin (PV)‐expressing GABAergic interneuron can evoke a disynaptic feedback excitatory postsynaptic potential (fbEPSP) onto the same presynaptic interneuron. Here, using whole‐cell recordings from PV‐expressing interneurons in acute brain slices we expand on this finding to show that this response is first detectable at 2‐week postnatal, and is most prevalent in animals beyond 3 we...

  13. Intracellular calcium modulates basolateral K(+)-permeability in frog skin epithelium

    DEFF Research Database (Denmark)

    Brodin, Birger; Rytved, K A; Nielsen, R

    1994-01-01

    Cytosolic calcium ([Ca2+]i) has been suggested as a key modulator in the regulation of active sodium transport across electrically "tight" (high resistance) epithelia. In this study we investigated the effects of calcium on cellular electrophysiological parameters in a classical model tissue......, the frog skin. [Ca2+]i was measured with fura-2 in an epifluorescence microscope setup. An inhibition of basolateral potassium permeability was observed when cytosolic calcium was increased. This inhibition was reversible upon removal of calcium from the serosal solution....

  14. 5-HT1A and benzodiazepine receptors in the basolateral amygdala modulate anxiety in the social interaction test, but not in the elevated plus-maze.

    Science.gov (United States)

    Gonzalez, L E; Andrews, N; File, S E

    1996-09-01

    In order to investigate the role of the 5-HT1A receptors of the amygdala in modulating anxiety, rats were implanted with bilateral cannulae aimed at the basolateral nucleus of the amygdala complex and infused with either artificial cerebrospinal fluid (aCSF) or the selective 5-HT1A receptor agonist 8-OH-DPAT (50-200 ng) and tested in two animal models of anxiety. In the elevated plus-maze test, no significant effects were detected in this dose range. In contrast, 8-OH-DPAT caused an overall reduction in levels of social investigation, thus indicating anxiogenic actions in the social interaction test. At 50 ng, 8-OH-DPAT had a selective action on anxiety, while at 200 ng there was a concomitant reduction in locomotor activity and, in some animals, signs of the 5-HT1A syndrome. Evidence that the anxiogenic effect of 8-OH-DPAT (50 ng) was due to activation of 5-HT1A receptors came from the finding that (-)-tertatolol, a 5-HT1A receptor antagonist, reversed this effect at a dose (1.5 micrograms) which was silent when given alone. The benzodiazepine receptor agonist, midazolam (1 and 2 micrograms) was bilaterally administered into the basolateral nucleus of the amygdala and evoked clear-cut anxiolytic effects in the social interaction test. These data indicate that the agonist activation of post-synaptic 5-HT1A receptors in the basolateral nucleus of the amygdala may produce anxiogenic effects, while agonist activation of BDZ receptors in the same areas evokes anxiolytic effects. Our results from the social interaction test are similar to those previously reported from tests of anxiety using punished paradigms, but contrast with those found in the elevated plus-maze. Thus, it is concluded that either the two tests have different sensitivities to midazolam and 8-OH-DPAT or more intriguingly, the tests are evoking fundamentally different states of anxiety, with that evoked by the plus-maze being mediated via brain areas or receptors different from those studied here.

  15. Prefrontal cortex, hippocampus, and basolateral amygdala plasticity in a rat model of autism spectrum.

    Science.gov (United States)

    Sosa-Díaz, Nuvia; Bringas, Maria Elena; Atzori, Marco; Flores, Gonzalo

    2014-10-01

    We aimed to investigate the effect of prenatal administration of valproic acid (VPA) (500 mg/kg) at embryonic day 12.5 on the anatomical properties of the prefrontal cortex, hippocampus, and basolateral amygdala, at three different ages: immediately after weaning (postnatal day 21 [PD21]), prepubertal (PD35), and postpubertal (PD70) ages in a rat model of autistic spectrum disorder. Quantitative analysis of the thickness of the prefrontal cortex revealed a reduced size at all study ages in the cingulate 1 area of the prefrontal cortex and CA1 of the dorsal hippocampus in prenatally exposed animals compared to controls. At the level of the basolateral amygdala, a reduction in the size was observed at PD35 and PD70 in the VPA group. In addition, a reduced thickness was observed in the prelimbic region of the prefrontal cortex in VPA animals at PD35. Interestingly, no differences in cortical thickness were observed between control and VPA animals in the infralimbic region of the prefrontal at any age. Our results suggest that prenatal exposure to VPA differentially alters cortical limbic regions anatomical parameters, with implication in the autistic spectrum disorder.

  16. Insulin-like growth factor II stimulates production of inositol trisphosphate in proximal tubular basolateral membranes from canine kidney.

    OpenAIRE

    Rogers, S A; Hammerman, M R

    1988-01-01

    To determine whether insulin-like growth factor II (IGF-II) activates phospholipase C in the basolateral membrane of the renal proximal tubular cell, we incubated basolateral membranes isolated from canine kidney with rat IGF-II (rIGF-II) and measured levels of inositol trisphosphate (Ins-P3) in suspensions and of diacylglycerol extractable from the membranes. Incubation with rIGF-II increased levels of Ins-P3 and diacylglycerol in a concentration-dependent manner. Significant enhancement of ...

  17. Hepatocyte growth factor activator inhibitor-1 has a complex subcellular itinerary

    DEFF Research Database (Denmark)

    Godiksen, Sine; Selzer-Plon, Joanna; Pedersen, Esben D K;

    2008-01-01

    it is a key regulator of carcinogenesis. HAI-1 is expressed in polarized epithelial cells, which have the plasma membrane divided by tight junctions into an apical and a basolateral domain. In the present study we show that HAI-1 at steady-state is mainly located on the basolateral membrane of both Madin...... in transporting matriptase as a matriptase-HAI-1 complex from the basolateral plama membrane to the apical plasma membrane, as matriptase is known to interact with prostasin, located at the apical plasma membrane....... and then recycles between the basolateral plasma membrane and endosomes for hours until it is transcytosed to the apical plasma membrane. Minor amounts of HAI-1 present at the apical plasma membrane are proteolytically cleaved and released into the apical medium. Full-length membrane-bound HAI-1 has a half...

  18. Noradrenergic Activation of the Basolateral Amygdala Enhances Object Recognition Memory and Induces Chromatin Remodeling in the Insular Cortex

    Directory of Open Access Journals (Sweden)

    Hassiba eBeldjoud

    2015-04-01

    Full Text Available It is well established that arousal-induced memory enhancement requires noradrenergic activation of the basolateral complex of the amygdala (BLA and modulatory influences on information storage processes in its many target regions. While this concept is well accepted, the molecular basis of such BLA effects on neural plasticity changes within other brain regions remains to be elucidated. The present study investigated whether noradrenergic activation of the BLA after object recognition training induces chromatin remodeling through histone post-translational modifications in the insular cortex (IC, a brain region that is importantly involved in object recognition memory. Male Sprague–Dawley rats were trained on an object recognition task, followed immediately by bilateral microinfusions of norepinephrine (1.0 µg or saline administered into the BLA. Saline-treated control rats exhibited poor 24-h retention, whereas norepinephrine treatment induced robust 24-h object recognition memory. Most importantly, this memory-enhancing dose of norepinephrine induced a global reduction in the acetylation levels of histone H3 at lysine 14, H2B and H4 in the IC 1 h later, whereas it had no effect on the phosphorylation of histone H3 at serine 10 or tri-methylation of histone H3 at lysine 27. Norepinephrine administered into the BLA of non-trained control rats did not induce any changes in the histone marks investigated in this study. These findings indicate that noradrenergic activation of the BLA induces training-specific effects on chromatin remodeling mechanisms, and presumably gene transcription, in its target regions, which may contribute to the understanding of the molecular mechanisms of stress and emotional arousal effects on memory consolidation.

  19. Relationship between the dose-response effects of diazepam and clobazam on electroencephalographic parameters and on kindled amygdaloid seizure activity in rats.

    Science.gov (United States)

    Harris, Q L; Lewis, S J; Young, N A; Vajda, F J; Jarrott, B

    1988-10-01

    1. The possibility that the anticonvulsant activity of the benzodiazepines, diazepam and clobazam, is related to changes in EEG parameters, particularly beta activity, was investigated in amygdaloid kindled rats. 2. The effects of diazepam (1, 2, 4, 8 and 16 mumols/kg), administered intraperitoneally (i.p.), clobazam (1, 2, 4, 8, 16 and 32 mumols/kg, i.p.) or vehicle (dimethyl sulfoxide) on the cortical EEG of amygdaloid kindled rats were quantitated for 15 min using computerized period amplitude analysis. Immediately afterwards, the amygdala was stimulated and the after-discharge duration (AD) and the seizures stage (SS) were determined. 3. The equivalent percentage time (EPT) of the diazepam-treated group was decreased in the theta band (4-8 Hz) and increased in the alpha (8-12 Hz) and first six beta (12-36 Hz) bands. The mean peak amplitude (MPA) was increased in the alpha (8-12 Hz) and all seven beta bands (12-40 Hz). Clobazam increased the EPT and MPA in the alpha (8-12 Hz) and all seven beta (12-40 Hz) bands. The MPA was also increased by clobazam in the theta (4-8 Hz) band. 4. Diazepam reduced both the AD and SS of the kindled seizures at doses of 4, 8 and 16 mumols/kg, whereas clobazam was anticonvulsant at doses of 16 and 32 mumols/kg. The reduction in both AD and SS correlated with increases in the EPT and MPA in the first beta (12-16 Hz) band in the diazepam-treated group and in the first four beta (12-28 Hz) bands in the clobazam-treated group.

  20. Trafficking of the IKs -Complex in MDCK Cells

    DEFF Research Database (Denmark)

    David, Jens-Peter; Andersen, Martin N; Olesen, Søren-Peter;

    2013-01-01

    has not been unequivocally resolved yet. We employed trafficking-deficient K 7.1 and KCNE1 mutants to investigate I trafficking using the polarized Madin-Darby Canine Kidney cell line. We find that the assembly happens early in the secretory pathway but provide three lines of evidence that it takes...... place in a post-endoplasmic reticulum compartment. We demonstrate that K 7.1 targets the I -complex to the basolateral membrane, but that KCNE1 can redirect the complex to the apical membrane upon mutation of critical K 7.1 basolateral targeting signals. Our data provide a possible explanation...

  1. Complexity

    CERN Document Server

    Gershenson, Carlos

    2011-01-01

    The term complexity derives etymologically from the Latin plexus, which means interwoven. Intuitively, this implies that something complex is composed by elements that are difficult to separate. This difficulty arises from the relevant interactions that take place between components. This lack of separability is at odds with the classical scientific method - which has been used since the times of Galileo, Newton, Descartes, and Laplace - and has also influenced philosophy and engineering. In recent decades, the scientific study of complexity and complex systems has proposed a paradigm shift in science and philosophy, proposing novel methods that take into account relevant interactions.

  2. Basolateral localisation of KCNQ1 potassium channels in MDCK cells: molecular identification of an N-terminal targeting motif

    DEFF Research Database (Denmark)

    Jespersen, Thomas; Rasmussen, Hanne B; Grunnet, Morten;

    2004-01-01

    KCNQ1 potassium channels are expressed in many epithelial tissues as well as in the heart. In epithelia KCNQ1 channels play an important role in salt and water transport and the channel has been reported to be located apically in some cell types and basolaterally in others. Here we show that KCNQ...

  3. Fasting induces basolateral uptake transporters of the SLC family in the liver via HNF4alpha and PGC1alpha.

    Science.gov (United States)

    Dietrich, Christoph G; Martin, Ina V; Porn, Anne C; Voigt, Sebastian; Gartung, Carsten; Trautwein, Christian; Geier, Andreas

    2007-09-01

    Fasting induces numerous adaptive changes in metabolism by several central signaling pathways, the most important represented by the HNF4alpha/PGC-1alpha-pathway. Because HNF4alpha has been identified as central regulator of basolateral bile acid transporters and a previous study reports increased basolateral bile acid uptake into the liver during fasting, we hypothesized that HNF4alpha is involved in fasting-induced bile acid uptake via upregulation of basolateral bile acid transporters. In rats, mRNA of Ntcp, Oatp1, and Oatp2 were significantly increased after 48 h of fasting. Protein expression as determined by Western blot showed significant increases for all three transporters 72 h after the onset of fasting. Whereas binding activity of HNF1alpha in electrophoretic mobility shift assays remained unchanged, HNF4alpha binding activity to the Ntcp promoter was increased significantly. In line with this result, we found significantly increased mRNA expression of HNF4alpha and PGC-1alpha. Functional studies in HepG2 cells revealed an increased endogenous NTCP mRNA expression upon cotransfection with either HNF4alpha, PGC-1alpha, or a combination of both. We conclude that upregulation of the basolateral bile acid transporters Ntcp, Oatp1, and Oatp2 in fasted rats is mediated via the HNF4alpha/PGC-1alpha pathway.

  4. Basolateral Amygdala Projections to Ventral Hippocampus Modulate the Consolidation of Footshock, but Not Contextual, Learning in Rats

    Science.gov (United States)

    Huff, Mary L.; Emmons, Eric B.; Narayanan, Nandakumar S.; LaLumiere, Ryan T.

    2016-01-01

    The basolateral amygdala (BLA) modulates memory consolidation for a variety of types of learning, whereas other brain regions play more selective roles in specific kinds of learning suggesting a role for differential consolidation via distinct BLA pathways. The ventral hippocampus (VH), an efferent target of the BLA, has been suggested to…

  5. Distinct Contributions of the Basolateral Amygdala and the Medial Prefrontal Cortex to Learning and Relearning Extinction of Context Conditioned Fear

    Science.gov (United States)

    Laurent, Vincent; Westbrook, R. Frederick

    2008-01-01

    We studied the roles of the basolateral amygdala (BLA) and the medial prefrontal cortex (mPFC) in learning and relearning to inhibit context conditioned fear (freezing) in extinction. In Experiment 1, pre-extinction BLA infusion of the NMDA receptor (NMDAr) antagonist, ifenprodil, impaired the development and retention of inhibition but…

  6. Anti-inflammatory activity of the basolateral fraction of Caco-2 cells exposed to a rosemary supercritical extract

    NARCIS (Netherlands)

    Arranz, E.; Mes, J.J.; Wichers, H.J.; Jaime, L.; Reglero, G.; Santoyo, S.

    2015-01-01

    The anti-inflammatory activity of the basolateral fraction of Caco-2 cells exposed to a rosemary supercritical extract was examined. Uptake of rosemary extract fractions was tested on Caco-2 cell monolayers (2–12 h incubation times) and the quantification of carnosic acid and carnosol was performed

  7. 17beta-Estradiol reduces excitatory postsynaptic potential (EPSP) amplitude in rat basolateral amygdala neurons.

    Science.gov (United States)

    Womble, Mark D; Andrew, James A; Crook, Joseph J

    2002-10-11

    We examined the actions of estrogen on excitatory synaptic transmission in the basolateral amygdala (BLA), a brain region involved in learning, emotions, and the effects of stress. Intracellular recordings of monosynaptic excitatory postsynaptic potentials (EPSPs) were obtained from BLA neurons in a slice preparation. Bath application of 17beta-estradiol (2 micro M) reduced EPSP amplitude by an average of 77%. This reduction was readily reversed by washing with control saline and was not mimicked by the inactive isomer 17 alpha-estradiol. Other passive and active properties of BLA neurons were unaffected by 17beta-estradiol. The observed EPSP reduction is in sharp contrast to the potentiation of EPSPs by estrogen observed in other brain regions.

  8. Neuropeptide S interacts with the basolateral amygdala noradrenergic system in facilitating object recognition memory consolidation.

    Science.gov (United States)

    Han, Ren-Wen; Xu, Hong-Jiao; Zhang, Rui-San; Wang, Pei; Chang, Min; Peng, Ya-Li; Deng, Ke-Yu; Wang, Rui

    2014-01-01

    The noradrenergic activity in the basolateral amygdala (BLA) was reported to be involved in the regulation of object recognition memory. As the BLA expresses high density of receptors for Neuropeptide S (NPS), we investigated whether the BLA is involved in mediating NPS's effects on object recognition memory consolidation and whether such effects require noradrenergic activity. Intracerebroventricular infusion of NPS (1nmol) post training facilitated 24-h memory in a mouse novel object recognition task. The memory-enhancing effect of NPS could be blocked by the β-adrenoceptor antagonist propranolol. Furthermore, post-training intra-BLA infusions of NPS (0.5nmol/side) improved 24-h memory for objects, which was impaired by co-administration of propranolol (0.5μg/side). Taken together, these results indicate that NPS interacts with the BLA noradrenergic system in improving object recognition memory during consolidation.

  9. Low-frequency stimulation of the kindling focus delays basolateral amygdala kindling in immature rats.

    Science.gov (United States)

    Velísek, Libor; Velísková, Jana; Stanton, Patric K

    2002-06-21

    Stimulation of deep brain sites is a new approach for treatment of intractable seizures. In adult rats, low-frequency stimulation (LFS; 1-3 Hz) of the kindling site interferes with the course of kindling epileptogenesis. In this study we determined whether the LFS will be effective against the fast kindling in the basolateral amygdala in immature, 15 day old rats. LFS (15 min of 1 Hz stimulation) was applied after each of the 1 s, 60 Hz kindling stimulus. LFS suppressed afterdischarge duration and seizure stage throughout the course of kindling, which indicates a strong antiepileptogenic potential. As the kindling and LFS stimulation patterns are similar to those used for induction of long-term potentiation and long-term depression (LTD), respectively, LTD or depotentiation may play a role in the mechanism of action.

  10. Protein synthesis inhibition in the basolateral nucleus of amygdala facilitates extinction of auditory fear memory

    Institute of Scientific and Technical Information of China (English)

    JIN XinChun; QI XueLian; YANG XiaoFei; LI BaoMing

    2007-01-01

    It is known that consolidation of fear conditioning requires de novo protein synthesis in the amygdala. However, there is controversy about the role of protein synthesis in post-retrieval extinction of fear memory. The present study investigated the effect of protein synthesis inhibition (PSI) in the basolateral nucleus of amygdala (BLA) on post-retrieval extinction of auditory fear memory. Intra-BLA infusion of the protein synthesis inhibitor anisomycin '0' h post-retrieval facilitated the extinction, but was ineffective if the memory was not retrieved. Anisomycin had no effect on the extinction when it was infused 6 h post-retrieval. The present results suggest that there exists a protein-synthesis-dependent mechanism in the BLA that retards extinction of auditory fear memory.

  11. Dynamic patterns of colocalization of calbindin, parvalbumin and GABA in subpopulations of mouse basolateral amygdalar cells during development.

    Science.gov (United States)

    Dávila, José Carlos; Olmos, Luis; Legaz, Isabel; Medina, Loreta; Guirado, Salvador; Real, Maria Angeles

    2008-01-01

    Calbindin cells represent a major interneuron subtype of the cortical/pallial regions, such as the basolateral amygdala, which are often analyzed in studies of tangential migration of interneurons from the subpallial ganglionic eminences to the pallium/cortex. However, previous evidence suggests that during development the calbindin cells may include more than one of the interneuron subtypes found in the adult pallium/cortex. Furthermore, in the adult basolateral amygdala, calbindin cells include a subpopulation of non-GABAergic (non-interneuron) cells. To better characterize these cells throughout development, in the present study we investigated the colocalization of calbindin, parvalbumin and GABA in cells of the mouse basolateral amygdala during late embryonic (E16.5) and several postnatal ages from birth until 4 weeks after birth (P0, P10 and P28). Our results indicate that CB, PV and GABA show a dynamic pattern of colocalization in cells of the mouse basolateral amygdalar nucleus throughout development. From E16.5 through P28, the majority of CB+ neurons and virtually all PV+ neurons are GABAergic. However, after P10, the percentage of GABAergic CB+ cells decline from 96% to 70%. Furthermore, while only 9% of CB+ neurons are PV+ at P10, this percentage raises to 42% at P28. At all postnatal ages studied, the majority of the PV+ cells are CB+, suggesting that PV+ interneurons develop postnatally mainly as a subpopulation within the CB+ cells of the basolateral amygdalar nucleus. These results are important for interpreting data from interneuron migration.

  12. Changes of glucocorticoid receptor mRNA expression in basolateral amygdale-kindled rats

    Institute of Scientific and Technical Information of China (English)

    BAO Guan-shui; CHENG Xu-qin; HUA Yin; WANG Zhe-dong; LIU Zhen-guo

    2011-01-01

    Background Glucocorticoid receptor (GR) is believed to be a major factor in brain maturation and in modulation of a series of brain activity.Hippocampal neurons are abundant in glucocorticoid receptor,and there is significant change in GR expression under certain pathological state.Epilepsy is a special pathological state of the central nervous system.This study aimed to explore the role of GR in epilepsy by observing the change and functions of GR in hippocampus with a basolateral amygdale-electrical kindled rat epilepsy model.Methods Firstly,we established the basolateral amygdale-electrical kindled rat epilepsy model.Then GR mRNA expression in the hippocampus was assayed by semi-quantitative reverse transcription-PCR in this experiment.In addition,the processes of epileptic seizures were observed and electroencephalograms were recorded.One-way analysis of variance (ANOVA) was employed for comparing means of multiple groups,followed Fisher's least significant difference (LSD) for paired comparison.Results The rats were successfully kindled after an average of (13.50±3.99) times electrical stimulation,in which it was showed that GR mRNA expression reduced obviously as compared with the control group and the sham groups (P<0.001).The down-regulation of GR mRNA expression was abated or reversed by some anti-epilepsy drugs (P <0.001 compared with the epilepsy group),accompanied by attenuation of seizures and improvement of electroencephalograms.Conclusions Down-regulation of hippocampal GR mRNA expression may be related to the kindling.Anti-epilepsy drugs exposure can retard this change.

  13. Macula densa basolateral ATP release is regulated by luminal [NaCl] and dietary salt intake.

    Science.gov (United States)

    Komlosi, Peter; Peti-Peterdi, Janos; Fuson, Amanda L; Fintha, Attila; Rosivall, Laszlo; Bell, Phillip Darwin

    2004-06-01

    One component of the macula densa (MD) tubuloglomerular feedback (TGF) signaling pathway may involve basolateral release of ATP through a maxi-anion channel. Release of ATP has previously been studied during a maximal luminal NaCl concentration ([NaCl](L)) stimulus (20-150 mmol/l). Whether MD ATP release occurs during changes in [NaCl](L) within the physiological range (20-60 mmol/l) has not been examined. Also, because TGF is known to be enhanced by low dietary salt intake, we examined the pattern of MD ATP release from salt-restricted rabbits. Fluorescence microscopy, with fura 2-loaded cultured mouse mesangial cells as biosensors, was used to assess ATP release from the isolated, perfused thick ascending limb containing the MD segment. The mesangial biosensor cells, which contain purinergic receptors and elevate intracellular Ca(2+) concentration ([Ca(2+)](i)) on ATP binding, were placed adjacent to the MD basolateral membrane. Elevations in [NaCl](L) between 0 and 80 mmol/l, in 20-mmol/l increments, caused stepwise increases in [Ca(2+)](i), with the highest increase at [NaCl](L) of approximately 60 mmol/l. Luminal furosemide at 10(-4) mol/l blocked ATP release, which suggests that the efflux of ATP required MD Na-2Cl-K cotransport. A low-salt diet for 1 wk increased the magnitude of [NaCl](L)-dependent elevations in biosensor [Ca(2+)](i) by twofold, whereas high-salt intake had no effect. In summary, ATP release occurs over the same range of [NaCl](L) (20-60 mmol/l) previously reported for TGF responses, and, similar to TGF, ATP release was enhanced by dietary salt restriction. Thus these two findings are consistent with the role of MD ATP release as a signaling component of the TGF pathway.

  14. Basolateral P2X receptors mediate inhibition of NaCl transport in mouse medullary thick ascending limb (mTAL)

    DEFF Research Database (Denmark)

    Marques, Rita D; de Bruijn, Pauline I.A.; Sørensen, Mads Vaarby;

    2012-01-01

    Extracellular nucleotides regulate epithelial transport via luminal and basolateral P2 receptors. Renal epithelia express multiple P2 receptors, which mediate significant inhibition of solute absorption. Recently, we identified several P2 receptors in the medullary thick ascending limb (m......TAL) including luminal and basolateral P2Y(2) receptors. In addition, we found evidence for a basolateral P2X receptor. Here we investigate the effect of basolateral ATP on NaCl absorption in isolated, perfused mouse mTALs using the electrical measurement of equivalent short circuit current (I'(sc)). Non...... receptor antagonist suramin blocked the effect. P2Y receptors were found not to be involved in this effect. The P2X receptor agonist 2MeSATP mimicked the ATP effect and the P2X receptor antagonist oATP blocked it. In P2X(7)(-/-) mice the ATP effect remained unaltered. In contrast, in P2X(4)(-/-) mice...

  15. Increased basolateral sorting of carcinoembryonic antigen in a polarized colon carcinoma cell line after cholesterol depletion-Implications for treatment of inflammatory bowel disease

    Institute of Scientific and Technical Information of China (English)

    Robert Ehehalt; Markus Krautter; Martin Zorn; Richard Sparla; Joachim Fūllekrug; Hasan Kulaksiz; Wolfgang Stremmel

    2008-01-01

    AIM:To investigate a possible increase of basolateral expression of carcinoembryonic antigen(CEA)by interfering with the apical transport machinery,we studied the effect of cholesterol depletion on CEA sorting and secretion.METHODS:Cholesterol depletion was performed in polarized Caco-2 cells using Iovastatin and methyl-βcyclodextrin.RESULTS:We show that CEA is predominantly expressed and secreted at the apical surface.Reduction of the cholesterol level of the cell by 40%-50% with Iovastatin and methyl-β-cyclodextrin led to a significant change of the apical-to-basolateral transport ratio towards the basolateral membrane.CONCLUSION:As basolateral expression of CEA has been suggested to have anti-inflamatory properties,Cholesterol depletion of enterocytes might be a potential approach to influence the course of inflammatory bowel disease.

  16. Bile Acids Trigger GLP-1 Release Predominantly by Accessing Basolaterally Located G Protein-Coupled Bile Acid Receptors

    DEFF Research Database (Denmark)

    Brighton, Cheryl A.; Rievaj, Juraj; Kuhre, Rune E.;

    2015-01-01

    Bile acids are well-recognized stimuli of glucagon-like peptide-1 (GLP-1) secretion. This action has been attributed to activation of the G protein-coupled bile acid receptor GPBAR1 (TGR5), although other potential bile acid sensors include the nuclear farnesoid receptor and the apical sodium......-coupled bile acid transporter ASBT. The aim of this study was to identify pathways important for GLP-1 release and to determine whether bile acids target their receptors on GLP-1-secreting L-cells from the apical or basolateral compartment. Using transgenic mice expressing fluorescent sensors specifically in L...... to either TLCA or TDCA. We conclude that the action of bile acids on GLP-1 secretion is predominantly mediated by GPBAR1 located on the basolateral L-cell membrane, suggesting that stimulation of gut hormone secretion may include postabsorptive mechanisms....

  17. Differential roles of the basolateral amygdala and nucleus basalis magnocellularis during post-reactivation contextual fear conditioning reconsolidation in rats.

    Science.gov (United States)

    Baldi, Elisabetta; Mariottini, Chiara; Bucherelli, Corrado

    2008-11-01

    The roles of the basolateral amygdala and nucleus basalis magnocellularis in fear conditioning reconsolidation were investigated by means of tetrodotoxin bilateral inactivation performed 96 h after conditioning, immediately after reactivation training. Footshocks of 1.2 mA intensity were employed to induce the generalization phenomenon. Basolateral amygdala inactivation disrupts the contextual fear response and its generalization but not acoustic CS trace retention, when measured 72 and 96 h after tetrodotoxin administration. Nucleus basalis magnocellularis functional inactivation does not affect memory post-reactivation phase of any of the three conditioned fear responses. The present findings show a differential role of the two structures in fear memory reconsolidation and can be a starting point for future investigation of the neural circuits subserving generalization.

  18. Macula densa Na(+)/H(+) exchange activities mediated by apical NHE2 and basolateral NHE4 isoforms.

    Science.gov (United States)

    Peti-Peterdi, J; Chambrey, R; Bebok, Z; Biemesderfer, D; St John, P L; Abrahamson, D R; Warnock, D G; Bell, P D

    2000-03-01

    Functional and immunohistochemical studies were performed to localize and identify Na(+)/H(+) exchanger (NHE) isoforms in macula densa cells. By using the isolated perfused thick ascending limb with attached glomerulus preparation dissected from rabbit kidney, intracellular pH (pH(i)) was measured with fluorescence microscopy by using 2',7'-bis-(2-carboxyethyl)-5-(and -6) carboxyfluorescein. NHE activity was assayed by measuring the initial rate of Na(+)-dependent pH(i) recovery from an acid load imposed by prior lumen and bath Na(+) removal. Removal of Na(+) from the bath resulted in a significant, DIDS-insensitive, ethylisopropyl amiloride (EIPA)-inhibitable decrease in pH(i). This basolateral transporter showed very low affinity for EIPA and Hoechst 694 (IC(50) = 9.0 and 247 microM, respectively, consistent with NHE4). The recently reported apical NHE was more sensitive to inhibition by these drugs (IC(50) = 0.86 and 7.6 microM, respectively, consistent with NHE2). Increasing osmolality, a known activator of NHE4, greatly stimulated basolateral NHE. Immunohistochemical studies using antibodies against NHE1-4 peptides demonstrated expression of NHE2 along the apical and NHE4 along the basolateral, membrane, whereas NHE1 and NHE3 were not detected. These results suggest that macula densa cells functionally and immunologically express NHE2 at the apical membrane and NHE4 at the basolateral membrane. These two isoforms likely participate in Na(+) transport, pH(i), and cell volume regulation and may be involved in tubuloglomerular feedback signaling by these cells.

  19. PAH clearance after renal ischemia and reperfusion is a function of impaired expression of basolateral Oat1 and Oat3

    OpenAIRE

    Bischoff, Ariane; Bucher, Michael; Gekle, Michael; Sauvant, Christoph

    2014-01-01

    Abstract Determination of renal plasma flow (RPF) by para‐aminohippurate (PAH) clearance leads to gross underestimation of this respective parameter due to impaired renal extraction of PAH after renal ischemia and reperfusion injury. However, no mechanistic explanation for this phenomenon is available. Based on our own previous studies we hypothesized that this may be due to impairment of expression of the basolateral rate limiting organic anion transporters Oat1 and Oat3. Thus, we investigat...

  20. Structural lipid changes and Na(+)/K(+)-ATPase activity of gill cells' basolateral membranes during saltwater acclimation in sea lamprey (Petromyzon marinus, L.) juveniles.

    Science.gov (United States)

    Lança, Maria João; Machado, Maria; Ferreira, Ana Filipa; Quintella, Bernardo Ruivo; de Almeida, Pedro Raposo

    2015-11-01

    Seawater acclimation is a critical period for anadromous species and a process yet to be understood in lampreys. Considering that changes in lipid composition of the gill cells' basolateral membranes may disrupt the major transporter Na(+)K(+)-ATPase, the goal of this study was to detect changes at this level during juvenile sea lamprey seawater acclimation. The results showed that saltwater acclimation has a direct effect on the fatty acid composition of gill cells basolateral membrane's phospholipids. When held in full-strength seawater, the fatty acid profile of basolateral membrane's phospholipids suffered a restructure by increasing either saturation or the ratio between oleic acid and eicosapentaenoic acid. Simultaneously, the activity of Na(+)K(+)-ATPase revealed a significant and positive correlation with basolateral membrane's cholesterol content in the presence of highest salinity. Our results pointed out for lipid adjustments involving the functional transporter present on the gill cell basolateral membranes to ensure the role played by branchial Na(+)K(+)-ATPase in ion transport during saltwater acclimation process. The responses observed contributed to the strategy adopted by gill cell's basolateral membranes to compensate for osmotic and ionic stressors, to ensure the success of the process of seawater acclimation associated with the downstream trophic migration of juvenile sea lamprey.

  1. PAH clearance after renal ischemia and reperfusion is a function of impaired expression of basolateral Oat1 and Oat3.

    Science.gov (United States)

    Bischoff, Ariane; Bucher, Michael; Gekle, Michael; Sauvant, Christoph

    2014-02-01

    Determination of renal plasma flow (RPF) by para-aminohippurate (PAH) clearance leads to gross underestimation of this respective parameter due to impaired renal extraction of PAH after renal ischemia and reperfusion injury. However, no mechanistic explanation for this phenomenon is available. Based on our own previous studies we hypothesized that this may be due to impairment of expression of the basolateral rate limiting organic anion transporters Oat1 and Oat3. Thus, we investigated this phenomenon in a rat model of renal ischemia and reperfusion by determining PAH clearance, PAH extraction, PAH net secretion, and the expression of rOat1 and rOat3. PAH extraction was seriously impaired after ischemia and reperfusion which led to a threefold underestimation of RPF when PAH extraction ratio was not considered. PAH extraction directly correlated with the expression of basolateral Oat1 and Oat3. Tubular PAH secretion directly correlated with PAH extraction. Consequently, our data offer an explanation for impaired renal PAH extraction by reduced expression of the rate limiting basolateral organic anion transporters Oat1 and Oat3. Moreover, we show that determination of PAH net secretion is suitable to correct PAH clearance for impaired extraction after ischemia and reperfusion in order to get valid results for RPF.

  2. Electron-microscopic characteristics of neuroendocrine neurons in the amygdaloid body of the brain in male rats and female rats at different stages of the estral cycle.

    Science.gov (United States)

    Akhmadeev, A V; Kalimullina, L B

    2008-01-01

    The ultrastructural features of neuroendocrine neurons in the dorsomedial nucleus (DMN) of the amygdaloid body of the brain - one of the major zones of sexual dimorphism - in 12 Wistar rats weighing 250-300 g were studied in three males and nine females at different stages of the estral cycle. On the basis of ultrastructural characteristics, analysis of the functional states of an average of 50 DMN neurons were studied in each animal. A morphofunctional classification reflecting hormone-dependent variations in neuron activity is proposed. DMN neurons were found to be in different structural-functional states, which could be classified as the states of rest, moderate activity, elevated activity, tension (maximal activity), decreased activity (types 1 and 2, depending on prior history), return to the initial state, and apoptosis. At the estrus stage, there was a predominance of neurons in the states of elevated activity (40% of all cells) and maximal activity (26%). At the metestrus stage, neurons in the state of decreased activity type 1 (with increased nuclear heterochromatin content) predominated (30% of cells), while 25% and 20% of cells were in the states of maximal activity and elevated activity respectively. In diestrus, neurons in the resting state, in moderate and elevated activity, in maximal activity, and in decreased activity type 1 were present in essentially identical proportions (18%, 21%, 18%, 20%, and 16% respectively). In males, 35% and 22% of neurons were in the states of elevated and maximal activity respectively. Neuron death was seen only in males.

  3. GABAA-mediated inhibition of basolateral amygdala blocks reward devaluation in macaques.

    Science.gov (United States)

    Wellman, Laurie L; Gale, Karen; Malkova, Ludise

    2005-05-04

    Amygdala ablation disrupts reinforcer "devaluation" in monkeys (Malkova et al., 1997). Here, we tested the hypothesis that transient inactivation of amygdala by the GABA(A) agonist muscimol (MUS), specifically during the period of reward satiation, would have a similar effect. Six pigtail macaques were trained on a visual object discrimination task in which 60 objects were associated with one of two specific food rewards. Subsequently, we evaluated the selective satiation-induced change (devaluation) in object preference in probe sessions. We also examined the effect of the amygdala inactivation during the probe sessions to determine whether the inactivation limited to the testing period (and not during the satiation period) is sufficient to impair the expression of reinforcer devaluation. MUS infusions were aimed at basolateral amygdala (BLA) in a pseudorandomized design; each monkey received MUS or saline either before or after selective satiation with each of the two food rewards (six infusions total). Under the control (saline) condition, the monkeys significantly shifted their preference from objects representing the sated food rewards to those representing the nonsated rewards (30% change). When BLA was inactivated during selective satiation (i.e., MUS infused before satiation), this devaluation effect was blocked. In contrast, MUS infusion after satiation, so that it was present just during the testing period, did not impair the shift in object preference (27% change). Thus, BLA is necessary for the appropriate registration of the change in the reinforcer value but not for the subsequent expression of the devaluation involving its transfer to secondary reinforcers.

  4. Transient inactivation of basolateral amygdala during selective satiation disrupts reinforcer devaluation in rats.

    Science.gov (United States)

    West, Elizabeth A; Forcelli, Patrick A; Murnen, Alice T; McCue, David L; Gale, Karen; Malkova, Ludise

    2012-08-01

    Basolateral amygdala (BLA) function is critical for flexible, goal-directed behavior, including performance on reinforcer devaluation tasks. Here we tested, in rats, the hypothesis that BLA is critical for conditioned reinforcer devaluation during the period when the primary reinforcer (food) is being devalued (by feeding it to satiety), but not thereafter for guiding behavioral choices. We used a spatially independent task that used two visual cues, each predicting one of two foods. An instrumental action (lever press) was required for reinforcer delivery. After training, rats received BLA or sham lesions, or cannulae implanted in BLA. Under control conditions (sham lesions, saline infusions), devaluation of one food significantly decreased responding to the cue associated with that food, when both cues were presented simultaneously during extinction. BLA lesions impaired this devaluation effect. Transient inactivation of BLA by microinfusion of the γ-aminobutyric acid receptor type A agonist muscimol resulted in an impairment only when BLA was inactivated during satiation. When muscimol was infused after satiation and therefore, BLA was inactivated only during the choice test, rats showed no impairment. Thus, BLA is necessary for registering or updating cues to reflect updated reinforcer values, but not for guiding choices once the value has been updated. Our results are the first to describe the contribution of rat BLA to specific components of reinforcer devaluation and are the first to show impairment in reinforcer devaluation following transient inactivation in the rat.

  5. Protein kinase A dependent phosphorylation activates Mg2+ efflux in the basolateral region of the liver.

    Science.gov (United States)

    Cefaratti, C; Ruse, Cristian

    2007-03-01

    Isolated hepatocytes in physiological [Na(+)]( 0 ) tightly maintain [Mg(2+)]( i ). Upon beta-adrenergic stimulation or in the presence of permeable cAMP, hepatocytes release 5-10% (1-3 mM Mg(2+)) of their total Mg(2+) content. However, isolated basolateral liver plasma membranes (bLPM), release Mg(2+) in the presence of [Na(+)]( o ) even in the absence of catecholamine stimulation. The data indicate that a physiological brake for Mg(2+) efflux is present in the hepatocyte and is removed upon cellular signaling. In contrast, this regulation "brake" is absent in purified bLPM thus rendering them fully active. The present study was carried out to reconstruct the missing regulatory component. Activation of Mg(2+) extrusion in intact cells is consistent with cAMP dependent phosphorylation of the transporter or a regulatory protein. Treatment of bLPM with a non-specific phosphatase such as alkaline phosphatase (AP), decreased Mg(2+) efflux by 70% compared to untreated bLPM. When AP-treated bLPM were loaded with protein kinase A (PKA), and stimulated with permeable cAMP, Mg(2+) transport fully recovered. These data suggest that phosphorylation of the Na(+)/Mg(2+) exchanger or a nearby protein activates the Mg(2+) transport mechanism in hepatocytes.

  6. Breathing is affected by dopamine D2-like receptors in the basolateral amygdala.

    Science.gov (United States)

    Sugita, Toshihisa; Kanamaru, Mitsuko; Iizuka, Makito; Sato, Kanako; Tsukada, Setsuro; Kawamura, Mitsuru; Homma, Ikuo; Izumizaki, Masahiko

    2015-04-01

    The precise mechanisms underlying how emotions change breathing patterns remain unclear, but dopamine is a candidate neurotransmitter in the process of emotion-associated breathing. We investigated whether basal dopamine release occurs in the basolateral amygdala (BLA), where sensory-related inputs are received and lead to fear or anxiety responses, and whether D1- and D2-like receptor antagonists affect breathing patterns and dopamine release in the BLA. Adult male mice (C57BL/6N) were perfused with artificial cerebrospinal fluid, a D1-like receptor antagonist (SCH 23390), or a D2-like receptor antagonist ((S)-(-)-sulpiride) through a microdialysis probe in the BLA. Respiratory variables were measured using a double-chamber plethysmograph. Dopamine release was measured by an HPLC. Perfusion of (S)-(-)-sulpiride in the BLA, not SCH 23390, specifically decreased respiratory rate without changes in local release of dopamine. These results suggest that basal dopamine release in the BLA, at least partially, increases respiratory rates only through post-synaptic D2-like receptors, not autoreceptors, which might be associated with emotional responses.

  7. Involvement of basolateral amygdala GABAA receptors in the effect of dexamethasone on memory in rats

    Institute of Scientific and Technical Information of China (English)

    Lotfollah KHAJEHPOUR; Acieh ALIZADEH-MAKVANDI; Mahnaz KESMATI; Hooman ESHAGH-HAROONI

    2011-01-01

    In this study we investigated whether GABAA receptors of the basolateral amygdala (BLA) interact with the effect of dexamethasone on the retrieval stage of memory.Adult male Wistar rats were bilaterally cannulated in the BLA by stereotaxic surgery.The animals were trained in step-through apparatus by induction of electric shock (1.5 mA,3 s) and were tested for memory retrieval after 1 d.The time of latency for entering the dark compartment of the instrument and the time spent by rats in this chamber were recorded for evaluation of the animals' retrieval in passive avoidance memory.Administration of dexamethasone (0.3 and 0.9 mg/kg,subcutaneously (s.c.)),immediately after training,enhanced memory retrieval.This effect was reduced by intra-BLA microinjection of muscimol (0.125,0.250 and 0.500 μg/rat),when administered before 0.9 mg/kg of dexamethasone.Microinjection of bicuculline (0.75 μg/rat,intra-BLA) with an ineffective dose of dexamethasone (0.1 mg/kg,s.c.) increased memory retrieval.However,the same doses of muscimol and bicuculline without dexamethasone did not affect memory processes.Our data support reports that dexamethasone enhances memory retrieval.It seems that GABAA receptors of the BLA mediate the effect of dexamethasone on memory retrieval in rats.

  8. Leptin receptor expression in the basolateral nucleus of amygdala of conditioned taste aversion rats

    Institute of Scientific and Technical Information of China (English)

    Zhen Han; Jian-Qun Yan; Guo-Gang Luo; Yong Liu; Yi-Li Wang

    2003-01-01

    AIM: To determine whether serum leptin level and the leptin receptor (OB-R) expression in the basolateral amygdala (BLA)change following conditioned taste aversion (CTA) formation.METHODS: The serum leptin concentration was measured by rat leptin RIA kit, long and short forms of leptin receptor (OB-Rb and OB-Ra) mRNA in the brain sections were examined by in situ hybridization (ISH) and the expression of OB-R was assessed by immunohistochemistry ABC method with a highly specific goat anti-OB-R antibody.RESULTS: The level of serum leptin didn't show significant difference between CTA and control group. Comparing with the control group, the CTA group had an increase on count of OB-R immunohistochemistry positive-stained cells in the BLA (127±12 vs 48±9 per 1 mm2). The OB-Rb mRNA expression level enhanced by 11.9 % in the BLA, while OBRa mRNA level increased by 7.4 % on the choroid plexus in CTA group. So BLA was supposed to be a region where interactions between gustatory and vagal signals take place.CONCLUSION: BLA is one of the sites, which are responsible for CTA formation in the brain. Leptin and OB-R maybe involved in neuronal communication for CTA. So leptin and its receptors probably take part in CTA and integration of autonomic and extroceptive information.

  9. Histamine in the basolateral amygdala promotes inhibitory avoidance learning independently of hippocampus.

    Science.gov (United States)

    Benetti, Fernando; Furini, Cristiane Regina Guerino; de Carvalho Myskiw, Jociane; Provensi, Gustavo; Passani, Maria Beatrice; Baldi, Elisabetta; Bucherelli, Corrado; Munari, Leonardo; Izquierdo, Ivan; Blandina, Patrizio

    2015-05-12

    Recent discoveries demonstrated that recruitment of alternative brain circuits permits compensation of memory impairments following damage to brain regions specialized in integrating and/or storing specific memories, including both dorsal hippocampus and basolateral amygdala (BLA). Here, we first report that the integrity of the brain histaminergic system is necessary for long-term, but not for short-term memory of step-down inhibitory avoidance (IA). Second, we found that phosphorylation of cyclic adenosine monophosphate (cAMP) responsive-element-binding protein, a crucial mediator in long-term memory formation, correlated anatomically and temporally with histamine-induced memory retrieval, showing the active involvement of histamine function in CA1 and BLA in different phases of memory consolidation. Third, we found that exogenous application of histamine in either hippocampal CA1 or BLA of brain histamine-depleted rats, hence amnesic, restored long-term memory; however, the time frame of memory rescue was different for the two brain structures, short lived (immediately posttraining) for BLA, long lasting (up to 6 h) for the CA1. Moreover, long-term memory was formed immediately after training restoring of histamine transmission only in the BLA. These findings reveal the essential role of histaminergic neurotransmission to provide the brain with the plasticity necessary to ensure memorization of emotionally salient events, through recruitment of alternative circuits. Hence, our findings indicate that the histaminergic system comprises parallel, coordinated pathways that provide compensatory plasticity when one brain structure is compromised.

  10. Histamine in the basolateral amygdala promotes inhibitory avoidance learning independently of hippocampus

    Science.gov (United States)

    Benetti, Fernando; Furini, Cristiane Regina Guerino; de Carvalho Myskiw, Jociane; Provensi, Gustavo; Passani, Maria Beatrice; Baldi, Elisabetta; Bucherelli, Corrado; Munari, Leonardo; Izquierdo, Ivan; Blandina, Patrizio

    2015-01-01

    Recent discoveries demonstrated that recruitment of alternative brain circuits permits compensation of memory impairments following damage to brain regions specialized in integrating and/or storing specific memories, including both dorsal hippocampus and basolateral amygdala (BLA). Here, we first report that the integrity of the brain histaminergic system is necessary for long-term, but not for short-term memory of step-down inhibitory avoidance (IA). Second, we found that phosphorylation of cyclic adenosine monophosphate (cAMP) responsive-element-binding protein, a crucial mediator in long-term memory formation, correlated anatomically and temporally with histamine-induced memory retrieval, showing the active involvement of histamine function in CA1 and BLA in different phases of memory consolidation. Third, we found that exogenous application of histamine in either hippocampal CA1 or BLA of brain histamine-depleted rats, hence amnesic, restored long-term memory; however, the time frame of memory rescue was different for the two brain structures, short lived (immediately posttraining) for BLA, long lasting (up to 6 h) for the CA1. Moreover, long-term memory was formed immediately after training restoring of histamine transmission only in the BLA. These findings reveal the essential role of histaminergic neurotransmission to provide the brain with the plasticity necessary to ensure memorization of emotionally salient events, through recruitment of alternative circuits. Hence, our findings indicate that the histaminergic system comprises parallel, coordinated pathways that provide compensatory plasticity when one brain structure is compromised. PMID:25918368

  11. Development and physiology of GABAergic feedback excitation in parvalbumin expressing interneurons of the mouse basolateral amygdala.

    Science.gov (United States)

    Spampanato, Jay; Sullivan, Robert K P; Perumal, Madhusoothanan B; Sah, Pankaj

    2016-01-01

    We have previously shown that in the basolateral amygdala (BLA), action potentials in one type of parvalbumin (PV)-expressing GABAergic interneuron can evoke a disynaptic feedback excitatory postsynaptic potential (fbEPSP) onto the same presynaptic interneuron. Here, using whole-cell recordings from PV-expressing interneurons in acute brain slices we expand on this finding to show that this response is first detectable at 2-week postnatal, and is most prevalent in animals beyond 3 weeks of age (>P21). This circuit has a very high fidelity, and single action potential evoked fbEPSPs display few failures. Reconstruction of filled neurons, and electron microscopy show that interneurons that receive feedback excitation make symmetrical synapses on both the axon initial segments (AIS), as well as the soma and proximal dendrites of local pyramidal neurons, suggesting fbEPSP interneurons are morphologically distinct from the highly specialized chandelier neurons that selectively target the axon initial segment of pyramidal neurons. Single PV interneurons could trigger very large (~ 1 nA) feedback excitatory postsynaptic currents (fbEPSCs) suggesting that these neurons are heavily reciprocally connected to local glutamatergic principal cells. We conclude that in the BLA, a subpopulation of PV interneurons forms a distinct neural circuit in which a single action potential can recruit multiple pyramidal neurons to discharge near simultaneously and feed back onto the presynaptic interneuron.

  12. Target-specific suppression of GABA release from parvalbumin interneurons in the basolateral amygdala by dopamine.

    Science.gov (United States)

    Chu, Hong-Yuan; Ito, Wataru; Li, Jiayang; Morozov, Alexei

    2012-10-17

    Dopamine (DA) in the basolateral amygdala (BLA) promotes fear learning by disinhibiting principal neurons (PNs) and enabling synaptic plasticity in their sensory inputs. While BLA interneurons (INs) are heterogeneous, it is unclear which interneuron subtypes decrease GABAergic input to PNs in the presence of DA. Here, using cell type-selective photostimulation by channelrhodopsin 2 in BLA slices from mouse brain, we examined the role of parvalbumin-positive INs (PV-INs), the major interneuronal subpopulation in BLA, in the disinhibitory effect of DA. We found that DA selectively suppressed GABAergic transmission from PV-INs to PNs by acting on presynaptic D(2) receptors, and this effect was mimicked by Rp-cAMP, an inhibitor of cAMP-dependent signaling. In contrast, DA did not alter GABA release from PV-INs to INs. Furthermore, neither suppressing cAMP-dependent signaling by Rp-cAMP nor enhancing it by forskolin altered GABA release from PV-INs to BLA INs. Overall, DA disinhibits BLA, at least in part, by suppressing GABA release from PV-INs in the target cell-specific manner that results from differential control of this release by cAMP-dependent signaling.

  13. Stimulus Intensity-dependent Modulations of Hippocampal Long-term Potentiation by Basolateral Amygdala Priming

    Directory of Open Access Journals (Sweden)

    Zexuan eLi

    2012-05-01

    Full Text Available There is growing realization that the relationship between memory and stress/emotionality is complicated, and may include both memory enhancing and memory impairing aspects. It has been suggested that the underlying mechanisms involve amygdalar modulation of hippocampal synaptic plasticity, such as long-term potentiation (LTP. We recently reported that while in CA1 basolateral amygdala (BLA priming impaired theta stimulation induced LTP, it enhanced LTP in the dentate gyrus (DG. However, emotional and stressfull experiences were found to activate synaptic plasticity within the BLA, rasing the possibility that BLA modulation of other brain regions may be altered as well, as it may depend on the way the BLA is activated or is responding. In previous studies BLA priming stimulation was relatively weak (1V, 50 µs pulse duration. In the present study we assessed the effects of two stronger levels of BLA priming stimulation (1V or 2V, 100 µs pulse duration on LTP induction in hippocampal DG and CA1, in anesthetized rats. Results show that 1V-BLA priming stimulation enhanced but 2V-BLA priming stimulation impaired DG LTP; however, both levels of BLA priming stimulation impaired CA1 LTP, suggesting that modulation of hippocampal synaptic plasticity by amygdala is dependent on the degree of amygdala activation. These findings suggest that plasticity induced within the amygdala, by stressful experiences induces a form of metaplasticity that would alter the way the amygdala may modulate memory-related processes in other brain areas, such as the hippocampus.

  14. Src family protein tyrosine kinase regulates the basolateral K channel in the distal convoluted tubule (DCT) by phosphorylation of KCNJ10 protein.

    Science.gov (United States)

    Zhang, Chengbiao; Wang, Lijun; Thomas, Sherin; Wang, Kemeng; Lin, Dao-Hong; Rinehart, Jesse; Wang, Wen-Hui

    2013-09-01

    The loss of function of the basolateral K channels in the distal nephron causes electrolyte imbalance. The aim of this study is to examine the role of Src family protein tyrosine kinase (SFK) in regulating K channels in the basolateral membrane of the mouse initial distal convoluted tubule (DCT1). Single-channel recordings confirmed that the 40-picosiemen (pS) K channel was the only type of K channel in the basolateral membrane of DCT1. The suppression of SFK reversibly inhibited the basolateral 40-pS K channel activity in cell-attached patches and decreased the Ba(2+)-sensitive whole-cell K currents in DCT1. Inhibition of SFK also shifted the K reversal potential from -65 to -43 mV, suggesting a role of SFK in determining the membrane potential in DCT1. Western blot analysis showed that KCNJ10 (Kir4.1), a key component of the basolateral 40-pS K channel in DCT1, was a tyrosine-phosphorylated protein. LC/MS analysis further confirmed that SFK phosphorylated KCNJ10 at Tyr(8) and Tyr(9). The single-channel recording detected the activity of a 19-pS K channel in KCNJ10-transfected HEK293T cells and a 40-pS K channel in the cells transfected with KCNJ10+KCNJ16 (Kir.5.1) that form a heterotetramer in the basolateral membrane of the DCT. Mutation of Tyr(9) did not alter the channel conductance of the homotetramer and heterotetramer. However, it decreased the whole-cell K currents, the probability of finding K channels, and surface expression of KCNJ10 in comparison to WT KCNJ10. We conclude that SFK stimulates the basolateral K channel activity in DCT1, at least partially, by phosphorylating Tyr(9) on KCNJ10. We speculate that the modulation of tyrosine phosphorylation of KCNJ10 should play a role in regulating membrane transport function in DCT1.

  15. Post-training depletions of basolateral amygdala serotonin fail to disrupt discrimination, retention, or reversal learning.

    Science.gov (United States)

    Ochoa, Jesus G; Stolyarova, Alexandra; Kaur, Amandeep; Hart, Evan E; Bugarin, Amador; Izquierdo, Alicia

    2015-01-01

    In goal-directed pursuits, the basolateral amygdala (BLA) is critical in learning about changes in the value of rewards. BLA-lesioned rats show enhanced reversal learning, a task employed to measure the flexibility of response to changes in reward. Similarly, there is a trend for enhanced discrimination learning, suggesting that BLA may modulate formation of stimulus-reward associations. There is a parallel literature on the importance of serotonin (5HT) in new stimulus-reward and reversal learning. Recent postulations implicate 5HT in learning from punishment. Whereas, dopaminergic involvement is critical in behavioral activation and reinforcement, 5HT may be most critical for aversive processing and behavioral inhibition, complementary cognitive processes. Given these findings, a 5HT-mediated mechanism in BLA may mediate the facilitated learning observed previously. The present study investigated the effects of selective 5HT lesions in BLA using 5,7-dihydroxytryptamine (5,7-DHT) vs. infusions of saline (Sham) on discrimination, retention, and deterministic reversal learning. Rats were required to reach an 85% correct pairwise discrimination and single reversal criterion prior to surgery. Postoperatively, rats were then tested on the (1) retention of the pretreatment discrimination pair, (2) discrimination of a novel pair, and (3) reversal learning performance. We found statistically comparable preoperative learning rates between groups, intact postoperative retention, and unaltered novel discrimination and reversal learning in 5,7-DHT rats. These findings suggest that 5HT in BLA is not required for formation and flexible adjustment of new stimulus-reward associations when the strategy to efficiently solve the task has already been learned. Given the complementary role of orbitofrontal cortex in reward learning and its interconnectivity with BLA, these findings add to the list of dissociable mechanisms for BLA and orbitofrontal cortex in reward learning.

  16. Basolateral amygdala CB1 cannabinoid receptors mediate nicotine-induced place preference.

    Science.gov (United States)

    Hashemizadeh, Shiva; Sardari, Maryam; Rezayof, Ameneh

    2014-06-03

    In the present study, the effects of bilateral microinjections of cannabinoid CB1 receptor agonist and antagonist into the basolateral amygdala (intra-BLA) on nicotine-induced place preference were examined in rats. A conditioned place preference (CPP) apparatus was used for the assessment of rewarding effects of the drugs in adult male Wistar rats. Subcutaneous (s.c.) administration of nicotine (0.2mg/kg) induced a significant CPP, without any effect on the locomotor activity during the testing phase. Intra-BLA microinjection of a non-selective cannabinoid CB1/CB2 receptor agonist, WIN 55,212-2 (0.1-0.5 μg/rat) with an ineffective dose of nicotine (0.1mg/kg, s.c.) induced a significant place preference. On the other hand, intra-BLA administration of AM251 (20-60 ng/rat), a selective cannabinoid CB1 receptor antagonist inhibited the acquisition of nicotine-induced place preference. It should be considered that the microinjection of the same doses of WIN 55,212-2 or AM251 into the BLA, by itself had no effect on the CPP score. The administration of a higher dose of AM251 (60 ng/rat) during the acquisition decreased the locomotor activity of animals on the testing phase. Interestingly, the microinjection of AM251 (20 and 40 ng/rat), but not WIN55,212-2 (0.1-0.5 μg/rat), into the BLA inhibited the expression of nicotine-induced place preference without any effect on the locomotor activity. Taken together, these findings support the possible role of endogenous cannabinoid system of the BLA in the acquisition and the expression of nicotine-induced place preference. Furthermore, it seems that there is a functional interaction between the BLA cannabinoid receptors and nicotine in producing the rewarding effects.

  17. Sulfate transport by chick renal tubule brush-border and basolateral membranes

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    Renfro, J.L.; Clark, N.B.; Metts, R.E.; Lynch, M.A.

    1987-01-01

    Brush-border and basolateral membrane vesicles (BBMV and BLMV, respectively) were prepared from chick kidney by a calcium precipitation method and by centrifugation on an 8% Percoll self-generating gradient, respectively. In BBMV a 100-mM Na gluconate gradient, out>in, caused concentrative (/sup 35/S) sulfate uptake approximately fivefold greater at 1 min than at 60 min (equilibrium) whether or not the membranes were short-circuited with 100 mM K gluconate, in=out, plus 20 ..mu..g valinomycin/mg protein. A 48-mM HCO/sub 3//sup -/ gradient, in>out, stimulated a 2.5-fold higher uptake at 1 min than at 60 min, and short circuiting as above had no effect on the magnitude of this response. Imposition of a H/sup +/ gradient caused concentrative uptake fourfold higher at 1 min than at equilibrium. Short circuiting as above or addition of 0.1 mM carbonyl cyanide m-chlorophenylhydrazone (CCCP) significantly inhibited the pH gradient effect. Creation of an inside positive electrical potential with 100 mM K gluconate, out>in, plus valinomycin, also caused concentrative sulfate uptake. Based on inhibitor/competitor effects, these are distinct sulfate transport processes. In chick BLMV, imposition of an HCO/sub 3//sup -/ gradient, in>out, produced concentrative sulfate uptake. 4-Acetamido-4'-isothiocyanostilbene 2,2'-disulfonic acid disodium at 0.1 mM was an effective inhibitor of BLMV bicarbonate-sulfate exchange.

  18. Inactivation of basolateral amygdala specifically eliminates palatability-related information in cortical sensory responses

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    Piette, Caitlin E.; Baez-Santiago, Madelyn A.; Reid, Emily E.; Katz, Donald B.; Moran, Anan

    2012-01-01

    Evidence indirectly implicates the amygdala as the primary processor of emotional information used by cortex to drive appropriate behavioral responses to stimuli. Taste provides an ideal system with which to test this hypothesis directly, as neurons in both basolateral amygdala (BLA) and gustatory cortex (GC)—anatomically interconnected nodes of the gustatory system—code the emotional valence of taste stimuli (i.e., palatability), in firing rate responses that progress similarly through “epochs.” The fact that palatability-related firing appears one epoch earlier in BLA than GC is broadly consistent with the hypothesis that such information may propagate from the former to the latter. Here, we provide evidence supporting this hypothesis, assaying taste responses in small GC single-neuron ensembles before, during and after temporarily inactivating BLA (BLAx) in awake rats. BLAx changed responses in 98% of taste-responsive GC neurons, altering the entirety of every taste response in many neurons. Most changes involved reductions in firing rate, but regardless of the direction of change, the effect of BLAx was epoch-specific: while firing rates were changed, the taste-specificity of responses remained stable; information about taste palatability, however, which normally resides in the “Late” epoch, was reduced in magnitude across the entire GC sample and outright eliminated in most neurons. Only in the specific minority of neurons for which BLAx enhanced responses did palatability-specificity survive undiminished. Our data therefore provide direct evidence that BLA is a necessary component of GC gustatory processing, and that cortical palatability processing in particular is, in part, a function of BLA activity. PMID:22815512

  19. Progressively Disrupted Intrinsic Functional Connectivity of Basolateral Amygdala in Very Early Alzheimer’s Disease

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    Marion Ortner

    2016-09-01

    Full Text Available Abstract:Very early Alzheimer’s disease (AD - i.e., AD at stages of mild cognitive impairment (MCI and mild dementia - is characterized by progressive structural and neuropathologic changes such as atrophy or tangle deposition in medial temporal lobes, including hippocampus and entorhinal cortex but also adjacent amygdala. While progressively disrupted intrinsic connectivity of hippocampus with other brain areas has been demonstrated by many studies, amygdala connectivity was rarely investigated in AD, notwithstanding its known relevance for emotion processing and mood disturbances, which are both important in early AD. Intrinsic functional connectivity (iFC patterns of hippocampus and amygdala overlap in healthy persons. Thus, we hypothesized that increased alteration of iFC patterns along AD is not limited to the hippocampus but also concerns the amygdala, independent from atrophy. To address this hypothesis, we applied structural and functional resting-state MRI in healthy controls (CON, n=33 and patients with AD in the stages of MCI (AD-MCI, n=38 and mild dementia (AD-D, n=36. Outcome measures were voxel-based morphometry (VBM values and region of interest-based intrinsic functional connectivity maps (iFC of basolateral amygdala, which has extended cortical connectivity. Amygdala VBM values were progressively reduced in patients (CON > AD-MCI and AD-D. Amygdala iFC was progressively reduced along impairment severity (CON > AD-MCI > AD-D, particularly for hippocampus, temporal lobes, and fronto-parietal areas. Notably, decreased iFC was independent of amygdala atrophy. Results demonstrate progressively impaired amygdala intrinsic connectivity in temporal and fronto-parietal lobes independent from increasing amygdala atrophy in very early AD. Data suggest that early AD disrupts intrinsic connectivity of medial temporal lobe key regions including that of amygdala.

  20. Luminal NaCl delivery regulates basolateral PGE2 release from macula densa cells.

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    Peti-Peterdi, Janos; Komlosi, Peter; Fuson, Amanda L; Guan, Youfei; Schneider, Andre; Qi, Zhonghua; Redha, Reyadh; Rosivall, Laszlo; Breyer, Matthew D; Bell, P Darwin

    2003-07-01

    Macula densa (MD) cells express COX-2 and COX-2-derived PGs appear to signal the release of renin from the renal juxtaglomerular apparatus, especially during volume depletion. However, the synthetic machinery and identity of the specific prostanoid released from intact MD cells remains uncertain. In the present studies, a novel biosensor tool was engineered to directly determine whether MD cells release PGE2 in response to low luminal NaCl concentration ([NaCl]L). HEK293 cells were transfected with the Ca2+-coupled E-prostanoid receptor EP1 (HEK/EP1) and loaded with fura-2. HEK/EP1 cells produced a significant elevation in intracellular [Ca2+] ([Ca2+]i) by 29.6 +/- 12.8 nM (n = 6) when positioned at the basolateral surface of isolated perfused MD cells and [NaCl]L was reduced from 150 mM to zero. HEK/EP1 [Ca2+]i responses were observed mainly in preparations from rabbits on a low-salt diet and were completely inhibited by either a selective COX-2 inhibitor or an EP1 antagonist, and also by 100 microM luminal furosemide. Also, 20-mM graduated reductions in [NaCl]L between 80 and 0 mM caused step-by-step increases in HEK/EP1 [Ca2+]i. Low-salt diet greatly increased the expression of both COX-2 and microsome-associated PGE synthase (mPGES) in the MD. These studies provide the first direct evidence that intact MD cells synthesize and release PGE2 during reduced luminal salt content and suggest that this response is important in the control of renin release and renal vascular resistance during salt deprivation.

  1. The role of basolateral amygdala adrenergic receptors in hippocampus dependent spatial memory in rat

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    Vafaei A.L.

    2008-03-01

    Full Text Available Background and the purpose of the study: There are extensive evidences indicating that the noradrenergic system of the basolateral nucleus of the amygdala (BLA is involved in memory processes. The present study investigated the role of the BLA adrenergic receptors (ARs in hippocampus dependent spatial memory in place avoidance task in male rat. Material and Methods: Long Evans rats (n=150 were trained to avoid footshock in a 60° segment while foraging for scattered food on a circular (80-cm diameter arena. The rats were injected bilaterally in the BLA specific ARS (Adrenergic receptors agonist norepinephrine (NE, 0.5 and 1 µg/µl and specific β-ARs antagonist propranolol (PRO, 0.5 and 1 µg/µl before acquisition, after training or before retrieval of the place avoidance task. Control rats received vehicle at the same volume. The learning in a single 30-min session was assessed 24h later by a 30-min extinction trial in which the time to first entrance and the number of entrances to the shocked area measured the avoidance memory. Results: Acquisition and consolidation were enhanced and impaired significantly by NE and PRO when the drugs were injected 10 min before or immediately after training, respectively. In contrast, neither NE nor PRO influenced animal performances when injected before retention testing. Conclusion: Findings of this study indicates that adrenergic system of the BLA plays an important role in regulation of memory storage and show further evidences for the opinion that the BLA plays an important role in integrating hormonal and neurotransmitter influences on memory storage.

  2. Enhancing second-order conditioning with lesions of the basolateral amygdala.

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    Holland, Peter C

    2016-04-01

    Because the occurrence of primary reinforcers in natural environments is relatively rare, conditioned reinforcement plays an important role in many accounts of behavior, including pathological behaviors such as the abuse of alcohol or drugs. As a result of pairing with natural or drug reinforcers, initially neutral cues acquire the ability to serve as reinforcers for subsequent learning. Accepting a major role for conditioned reinforcement in everyday learning is complicated by the often-evanescent nature of this phenomenon in the laboratory, especially when primary reinforcers are entirely absent from the test situation. Here, I found that under certain conditions, the impact of conditioned reinforcement could be extended by lesions of the basolateral amygdala (BLA). Rats received first-order Pavlovian conditioning pairings of 1 visual conditioned stimulus (CS) with food prior to receiving excitotoxic or sham lesions of the BLA, and first-order pairings of another visual CS with food after that surgery. Finally, each rat received second-order pairings of a different auditory cue with each visual first-order CS. As in prior studies, relative to sham-lesioned control rats, lesioned rats were impaired in their acquisition of second-order conditioning to the auditory cue paired with the first-order CS that was trained after surgery. However, lesioned rats showed enhanced and prolonged second-order conditioning to the auditory cue paired with the first-order CS that was trained before amygdala damage was made. Implications for an enhanced role for conditioned reinforcement by drug-related cues after drug-induced alterations in neural plasticity are discussed. (PsycINFO Database Record

  3. Post-training depletions of basolateral amygdala serotonin fail to disrupt discrimination, retention, or reversal learning

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    G. Jesus eOchoa

    2015-05-01

    Full Text Available In goal-directed pursuits, the basolateral amygdala (BLA is critical in learning about changes in the value of rewards. BLA-lesioned rats show enhanced reversal learning, a task employed to measure the flexibility of response to changes in reward. Similarly, there is a trend for enhanced discrimination learning, suggesting that BLA may modulate formation of stimulus-reward associations. There is a parallel literature on the importance of serotonin (5HT in new stimulus-reward and reversal learning. Recent postulations implicate 5HT in learning from punishment. Whereas dopaminergic involvement is critical in behavioral activation and reinforcement, 5HT may be most critical for aversive processing and behavioral inhibition, complementary cognitive processes. Given these findings, a 5HT-mediated mechanism in BLA may mediate the facilitated learning observed previously. The present study investigated the effects of selective 5HT lesions in BLA using 5,7-dihydroxytryptamine (5,7-DHT versus infusions of saline (Sham on discrimination, retention, and deterministic reversal learning. Rats were required to reach an 85% correct pairwise discrimination and single reversal criterion prior to surgery. Postoperatively, rats were then tested on the 1 retention of the pretreatment discrimination pair 2 discrimination of a novel pair and 3 reversal learning performance. We found statistically comparable preoperative learning rates between groups, intact postoperative retention, and unaltered novel discrimination and reversal learning in 5,7-DHT rats. These findings suggest that 5HT in BLA is not required for formation and flexible adjustment of new stimulus-reward associations when the strategy to efficiently solve the task has already been learned. Given the complementary role of orbitofrontal cortex in reward learning and its interconnectivity with BLA, these findings add to the list of dissociable mechanisms for BLA and orbitofrontal cortex in reward learning.

  4. Basolateral membrane Na+/H+ exchange enhances HCO3- absorption in rat medullary thick ascending limb: evidence for functional coupling between basolateral and apical membrane Na+/H+ exchangers.

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    Good, D W; George, T; Watts, B A

    1995-01-01

    The role of basolateral membrane Na+/H+ exchange in transepithelial HCO3- absorption (JHCO3) was examined in the isolated, perfused medullary thick ascending limb (MTAL) of the rat. In Na(+)-free solutions, addition of Na+ to the bath resulted in a rapid, amiloride-sensitive increase in intracellular pH. In MTALs perfused and bathed with solutions containing 146 mM Na+ and 25 mM HCO3-, bath addition of amiloride (1 mM) or 5-(N-ethyl-N-isopropyl) amiloride (EIPA, 50 microM) reversibly inhibited JHCO3 by 50%. Evidence that the inhibition of JHCO3 by bath amiloride was the result of inhibition of Na+/H+ exchange included the following: (i) the IC50 for amiloride was 5-10 microM, (ii) EIPA was a 50-fold more potent inhibitor than amiloride, (iii) the inhibition by bath amiloride was Na+ dependent, and (iv) significant inhibition was observed with EIPA as low as 0.1 microM. Fifty micromolar amiloride or 1 microM EIPA inhibited JHCO3 by 35% when added to the bath but had no effect when added to the tubule lumen, indicating that addition of amiloride to the bath did not directly inhibit apical membrane Na+/H+ exchange. In experiments in which apical Na+/H+ exchange was assessed from the initial rate of cell acidification following luminal EIPA addition, bath EIPA secondarily inhibited apical Na+/H+ exchange activity by 46%. These results demonstrate basolateral membrane Na+/H+ exchange enhances transepithelial HCO3- absorption in the MTAL. This effect appears to be the result of cross-talk in which an increase in basolateral membrane Na+/H+ exchange activity secondarily increases apical membrane Na+/H+ exchange activity. PMID:8618934

  5. A light and electron microscopic analysis of the convergent insular cortical and amygdaloid projections to the posterior lateral hypothalamus in the rat, with special reference to cardiovascular function.

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    Tsumori, Toshiko; Yokota, Shigefumi; Qin, Yi; Oka, Tatsuro; Yasui, Yukihiko

    2006-11-01

    The synaptic organization between and among the insular cortex (IC) axons, central amygdaloid nucleus (ACe) axons and posterolateral hypothalamus (PLH) neurons was investigated in the rat using double anterograde tracing and anterograde tracing combined with postembedding immunogold analysis. After ipsilateral injections of biotinylated dextran amine (BDA) into the IC and Phaseolus vulgaris-leucoagglutinin (PHA-L) into the ACe, the conspicuous overlapping distribution of BDA-labeled axon terminals and PHA-L-labeled axon terminals was found in the PLH region just medial to the subthalamic nucleus ipsilateral to the injection sites. At the electron microscopic level, approximately two-thirds of the IC terminals made synapses with small-sized dendrites and the rest did with dendritic spines of the PLH neurons, whereas about 79%, 16% and 5% of the ACe terminals established synapses with small- to medium-sized dendrites, somata, and dendritic spines, respectively, of the PLH neurons. In addition, the IC axon terminals contained densely packed round clear vesicles and their synapses were of asymmetrical type. On the other hand, most of the ACe terminals contained not only pleomorphic clear vesicles but also dense-cored vesicles and their synapses were of symmetrical type although some ACe terminals contained densely packed round clear vesicles and formed asymmetrical synapses. Most of the postsynaptic elements received synaptic inputs from the IC or ACe terminals, and some of single postsynaptic elements received convergent synaptic inputs from both sets of terminals. Furthermore, almost all the ACe terminals were revealed to be immunoreactive for gamma-aminobutyric acid (GABA), by using the anterograde BDA tracing technique combined with immunohistochemistry for GABA. The present data suggest that single PLH neurons are under the excitatory influence of the IC and/or inhibitory influence of the ACe in the circuitry involved in the regulation of cardiovascular functions.

  6. Fructose-1,6-diphosphate protects against epileptogenesis by modifying cation-chloride co-transporters in a model of amygdaloid-kindling temporal epilepticus.

    Science.gov (United States)

    Ding, Yao; Wang, Shan; Jiang, Yan; Yang, Yi; Zhang, Manman; Guo, Yi; Wang, Shuang; Ding, Mei-ping

    2013-11-20

    Fructose-1,6-diphosphate (FDP) shifts the metabolism of glucose from glycolysis to the pentose phosphate pathway and has anticonvulsant activity in several acute seizure animal models. In the present study, we investigated the anti-epileptogenic effects of FDP in an amygdaloid-kindling seizure model, which is an animal model of the most common form of human temporal lobe epilepsy. We found that 1.0 g/kg FDP slowed seizure progression and shortened the corresponding after-discharge duration (ADD). FDP increased the number of stimulations needed to reach seizure stages 2-5 and prolonged the cumulative ADD prior to reaching stages 3-5. It also shortened staying days and cumulative ADD in stages 4-5. However, it demonstrated no significant protective effect when administered after the animals were fully kindled. In hippocampal neurons, cation-chloride co-transporters (CCCs) are suggested to play interesting roles in epilepsy by modulating γ-aminobutyric acid (GABA)ergic activity through controlling GABAA receptor-mediated reversal potential. We examined the potential link between FDP and the hippocampal expression of two main members of the CCCs: the neuron-specific K(+)-Cl(-)co-transporter 2 (KCC2) and Na(+)-K(+)-Cl(-)co-transporter 1 (NKCC1). FDP inhibited the kindling-induced downregulation of KCC2 expression and decreased NKCC1 expression during the kindling session. Taken together, our data reveal that FDP may have protective activity against epileptogenesis, from partial to generalized tonic-clonic seizures. Furthermore, our findings suggest that the FDP-induced imbalance between KCC2 and NKCC1 expression may be involved in the neuroprotective effect.

  7. LXR/RXR ligand activation enhances basolateral efflux of beta-sitosterol in CaCo-2 cells.

    Science.gov (United States)

    Field, F Jeffrey; Born, Ella; Mathur, Satya N

    2004-05-01

    To examine whether intestinal ABCA1 was responsible for the differences observed between cholesterol and beta-sitosterol absorption, ABCA1-facilitated beta-sitosterol efflux was investigated in CaCo-2 cells following liver X receptor/retinoid X receptor (LXR/RXR) activation. Both the LXR agonist T0901317 and the natural RXR/LXR agonists 22-hydroxycholesterol and 9-cis retinoic acid enhanced the basolateral efflux of beta-sitosterol without altering apical efflux. LXR-mediated enhanced beta-sitosterol efflux occurred between 6 h and 12 h after activation, suggesting that transcription, protein synthesis, and trafficking was likely necessary prior to facilitating efflux. The transcription inhibitor actinomycin D prevented the increase in beta-sitosterol efflux by T0901317. Glybenclamide, an inhibitor of ABCA1 activity, and arachidonic acid, a fatty acid that interferes with LXR activation, also prevented beta-sitosterol efflux in response to the LXR ligand activation. Influx of beta-sitosterol mass did not alter the basolateral or apical efflux of the plant sterol, nor did it alter ABCA1, ABCG1, ABCG5, or ABCG8 gene expression or ABCA1 mass. Similar to results observed with intestinal ABCA1-facilitated cholesterol efflux, LXR/RXR ligand activation enhanced the basolateral efflux of beta-sitosterol without affecting apical efflux. The results suggest that ABCA1 does not differentiate between cholesterol and beta-sitosterol and thus is not responsible for the selectivity of sterol absorption by the intestine. ABCA1, however, may play a role in beta-sitosterol absorption.

  8. Purinergic receptor signaling at the basolateral membrane of macula densa cells.

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    Liu, Ruisheng; Bell, P Darwin; Peti-Peterdi, Janos; Kovacs, Gergly; Johansson, Alf; Persson, A Erik G

    2002-05-01

    Purinergic receptors are important in the regulation of renal hemodynamics; therefore, this study sought to determine if such receptors influence macula densa cell function. Isolated glomeruli containing macula densa cells, with and without the cortical thick ascending limb, were loaded with the Ca(2+) sensitive indicators, Fura Red (confocal microscopy) or fura 2 (conventional video image analysis). Studies were performed on an inverted microscope in a chamber with a flow-through perfusion system. Changes in cytosolic calcium concentration ([Ca(2+)](i)) from exposed macula densa plaques were assessed upon addition of adenosine, ATP, UTP, ADP, or 2-methylthio-ATP (2- MeS-ATP) for 2 min added to the bathing solution. There was no change in [Ca(2+)](i) with addition of adenosine (10(-7) to 10(-3) M). UTP and ATP (10(-4) M) caused [Ca(2+)](i) to increase by 268 +/- 40 nM (n = 21) and 295 +/- 53 nM (n = 21), respectively, whereas in response to 2MesATP and ADP, [Ca(2+)](i) increased by only 67 +/- 13 nM (n = 8) and 93 +/- 36 nM (n = 14), respectively. Dose response curve for ATP (10(-7) to 10(-3) M) added in bath showed an EC(50) of 15 microM. No effect on macula densa [Ca(2+)](i) was seen when ATP was added from the lumen. ATP caused similar increases in macula densa [Ca(2+)](i) in the presence or absence of bath Ca(2+) and addition of 5 mM ethyleneglycotetraacetic acid (EGTA). Suramin (an antagonist of P2X and P2Y receptors) completely inhibited ATP-induced [Ca(2+)](i) dynamics. Also, ATP-Ca(2+) responsiveness was prevented by the phospholipase C inhibitor, U-73122, but not by its inactive analog, U-73343. These results suggest that macula densa cells possess P2Y(2) purinergic receptors on basolateral but not apical membranes and that activation of these receptors results in the mobilization of Ca(2+).

  9. Third trimester-equivalent ethanol exposure increases anxiety-like behavior and glutamatergic transmission in the basolateral amygdala.

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    Baculis, Brian C; Diaz, Marvin R; Valenzuela, C Fernando

    2015-10-01

    Ethanol consumption during pregnancy produces a wide range of morphological and behavioral alterations known as fetal alcohol spectrum disorder (FASD). Among the behavioral deficits associated with FASD is an increased probability of developing anxiety disorders. Studies with animal models of FASD have demonstrated that ethanol exposure during the equivalent to the 1(st) and 2(nd) trimesters of human pregnancy increases anxiety-like behavior. Here, we examined the impact on this type of behavior of exposure to high doses of ethanol in vapor inhalation chambers during the rat equivalent to the human 3rd trimester of pregnancy (i.e., neonatal period in these animals). We evaluated anxiety-like behavior with the elevated plus maze. Using whole-cell patch-clamp electrophysiological techniques in brain slices, we also characterized glutamatergic and GABAergic synaptic transmission in the basolateral amygdala, a brain region that has been implicated to play a role in emotional behavior. We found that ethanol-exposed adolescent offspring preferred the closed arms over the open arms in the elevated plus maze and displayed lower head dipping activity than controls. Electrophysiological measurements showed an increase in the frequency of spontaneous and miniature excitatory postsynaptic currents in pyramidal neurons from the ethanol group. These findings suggest that high-dose ethanol exposure during the equivalent to the last trimester of human pregnancy can persistently increase excitatory synaptic inputs to principal neurons in the basolateral amygdala, leading to an increase in anxiety-like behaviors.

  10. Fatty acids affect micellar properties and modulate vitamin D uptake and basolateral efflux in Caco-2 cells.

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    Goncalves, Aurélie; Gleize, Béatrice; Roi, Stéphanie; Nowicki, Marion; Dhaussy, Amélie; Huertas, Alain; Amiot, Marie-Josèphe; Reboul, Emmanuelle

    2013-10-01

    We have recently shown that vitamin D3 (cholecalciferol) absorption is not a simple passive diffusion but involves cholesterol transporters. As free fatty acids (FAs) modulate cholesterol intestinal absorption and metabolism, we hypothesized that FAs may also interact with vitamin D absorption. Effects of FAs were evaluated at different levels of cholecalciferol intestinal absorption. First, the physicochemical properties of micelles formed with different FAs were analyzed. The micelles were then administered to human Caco-2 cells in culture to evaluate FA effects on (i) cholecalciferol uptake and basolateral efflux and (ii) the regulation of genes coding proteins involved in lipid absorption process. Micellar electric charge was correlated with both FA chain length and degree of unsaturation. Long-chain FAs at 500 μM in mixed micelles decreased cholecalciferol uptake in Caco-2 cells. This decrease was annihilated as soon as the long-chain FAs were mixed with other FAs. Oleic acid significantly improved cholecalciferol basolateral efflux compared to other FAs. These results were partly explained by a modulation of genes coding for lipid transport proteins such as Niemann-pick C1-like 1 and scavenger receptor class B type I. The data reported here show for the first time that FAs can interact with cholecalciferol intestinal absorption at different key steps of the absorption process. Cholecalciferol intestinal absorption may thus be optimized according to oil FA composition.

  11. Clinical observation of physiological and psychological reactions to electric stimulation of the amygdaloid nucleus and the nucleus accumbens in heroin addicts after detoxification

    Institute of Scientific and Technical Information of China (English)

    FANG Jun; GU Jian-wen; YANG Wen-tao; QIN Xue-ying; HU Yong-hua

    2012-01-01

    Background Stereotactic surgery has been used to treat heroin abstinence in China since 2000 by ablating the amygdaloid nucleus (AMY) and the nucleus accumbens (NAc),which also provides opportunity to identify the relationship between these nuclei and addiction.Our study aimed to explore the physiological and psychological effects of electrically stimulating the AMY and the NAc in herein addicts after detoxification by observing changes of heart rate,arterial pressure and occurrence of euphoria similar to heroin induced euphoria.Methods A total of 70 heroin addicts after detoxification were recruited,and 61 of them were eligible to be given stereotactic surgery for heroin abstinence.The operation was carried out after determining the coordinates of all target nucleuses,and stimulation was performed at the AMY and the NAc solely or jointly.Heart rate,arterial pressure and occurrence of euphoria similar to heroin induced euphoria were recorded and analyzed.Results The average heat rate was (66±10) beats/min before electric stimulation,and significantly increased to (84±14) beats/min during stimulation,and changed to (73±12) beats/min 10 minutes after stimulation.There was a significant elevation of the average arterial pressure from 83 mmHg before stimulation to 98 mmHg during the stimulation,and it then decreased to 90 mmHg after stimulation.Forty-three of the 61 patients showed intense euphoria similar to heroin induced euphoria.The largest number (118/186) of euphoric responses occurred when the AMY and the NAc were stimulated at the same time.Odds ratio was 5.4 (95% CI: 2.4-11.9,P <0.0001) to quantify the association.Results from a Logistic regression model showed a positive correlation between unilateral stimulation of either the AMY or NAC and induction of euphoria (OR >1 ),especially when the left AMY or left NAc was stimulated (P <0.05).Conclusions Our data are consistent with existing results that the AMY and the NAc are related to addiction

  12. Activation of ERK2 in basolateral amygdala underlies the promoting influence of stress on fear memory and anxiety: influence of midazolam pretreatment.

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    Maldonado, N M; Espejo, P J; Martijena, I D; Molina, V A

    2014-02-01

    Exposure to emotionally arousing experiences elicits a robust and persistent memory and enhances anxiety. The amygdala complex plays a key role in stress-induced emotional processing and in the fear memory formation. It is well known that ERK activation in the amygdala is a prerequisite for fear memory consolidation. Moreover, stress elevates p-ERK2 levels in several areas of the brain stress circuitry. Therefore, given that the ERK1/2 cascade is activated following stress and that the role of this cascade is critical in the formation of fear memory, the present study investigated the potential involvement of p-ERK2 in amygdala subnuclei in the promoting influence of stress on fear memory formation and on anxiety-like behavior. A robust and persistent ERK2 activation was noted in the Basolateral amygdala (BLA), which was evident at 5min after restraint and lasted at least one day after the stressful experience. Midazolam, a short-acting benzodiazepine ligand, administered prior to stress prevented the increase in the p-ERK2 level in the BLA. Pretreatment with intra-BLA infusion of U0126 (MEK inhibitor), but not into the adjacent central nucleus of the amygdala, attenuated the stress-induced promoting influence on fear memory formation. Finally, U0126 intra-BLA infusion prevented the enhancement of anxiety-like behavior in stressed animals. These findings suggest that the selective ERK2 activation in BLA following stress exposure is an important mechanism for the occurrence of the promoting influence of stress on fear memory and on anxiety-like behavior.

  13. Activation of exchange protein activated by cAMP in the rat basolateral amygdala impairs reconsolidation of a memory associated with self-administered cocaine.

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    Xun Wan

    Full Text Available The intracellular mechanisms underlying memory reconsolidation critically involve cAMP signaling. These events were originally attributed to PKA activation by cAMP, but the identification of Exchange Protein Activated by cAMP (Epac, as a distinct mediator of cAMP signaling, suggests that cAMP-regulated processes that subserve memory reconsolidation are more complex. Here we investigated how activation of Epac with 8-pCPT-cAMP (8-CPT impacts reconsolidation of a memory that had been associated with cocaine self-administration. Rats were trained to lever press for cocaine on an FR-1 schedule, in which each cocaine delivery was paired with a tone+light cue. Lever pressing was then extinguished in the absence of cue presentations and cocaine delivery. Following the last day of extinction, rats were put in a novel context, in which the conditioned cue was presented to reactivate the cocaine-associated memory. Immediate bilateral infusions of 8-CPT into the basolateral amygdala (BLA following reactivation disrupted subsequent cue-induced reinstatement in a dose-dependent manner, and modestly reduced responding for conditioned reinforcement. When 8-CPT infusions were delayed for 3 hours after the cue reactivation session or were given after a cue extinction session, no effect on cue-induced reinstatement was observed. Co-administration of 8-CPT and the PKA activator 6-Bnz-cAMP (10 nmol/side rescued memory reconsolidation while 6-Bnz alone had no effect, suggesting an antagonizing interaction between the two cAMP signaling substrates. Taken together, these studies suggest that activation of Epac represents a parallel cAMP-dependent pathway that can inhibit reconsolidation of cocaine-cue memories and reduce the ability of the cue to produce reinstatement of cocaine-seeking behavior.

  14. Intracellular mechanisms of cocaine-memory reconsolidation in the basolateral amygdala and dorsal hippocampus

    Science.gov (United States)

    Wells, Audrey Marie

    The ability of cocaine-associated environmental contexts to promote relapse in abstinent humans and reinstatement of cocaine-seeking behavior in laboratory animals depends on the formation and maintenance of maladaptive context-response-cocaine associative memories, the latter of which can be disrupted by manipulations that interfere with memory reconsolidation. Memory reconsolidation refers to a protein synthesis-dependent phenomenon whereby memory traces are reincorporated back into long-term memory storage following their retrieval and subsequent destabilization. To elucidate the distinctive roles of the basolateral amygdala (BLA) and dorsal hippocampus (DH) in the reconsolidation of context-response-cocaine memories, Experiments 1-3 evaluated novel molecular mechanisms within each structure that control this phenomenon. Experiment 1 tested the hypothesis that activation of the extracellular signal-regulated kinase (ERK) in the BLA and nucleus accumbens core (NACc - a substrate for Pavlovian cocaine-memory reconsolidation) would critically control instrumental cocaine-memory reconsolidation. To determine this, rats were re-exposed to a context that had previously been used for cocaine self-administration (i.e., cocaine memory-reactivation) and immediately thereafter received bilateral intra-BLA or intra-NACc microinfusions of the ERK inhibitor U0126 or vehicle (VEH) and were subsequently tested for drug context-induced cocaine-seeking behavior (non-reinforced lever responding) ~72 h later. Re-exposure to the cocaine-paired context at test fully reinstated cocaine-seeking behavior, relative to responding in an alternate, extinction context, and post-reactivation U0126 treatment in the BLA, but not the NACc, impaired cocaine-seeking behavior, relative to VEH. This effect was associated with a temporary increase in ERK2, but not ERK1, phosphorylation in the BLA and required explicit reactivation of the target memory trace (i.e., did not similarly manifest when U

  15. Basolateral Na+/HCO3– cotransport activity is regulated by the dissociable Na+/H+ exchanger regulatory factor

    Science.gov (United States)

    Bernardo, Angelito A.; Kear, Felicidad T.; Santos, Anna V.P.; Ma, Jianfei; Steplock, Debra; Robey, R. Brooks; Weinman, Edward J.

    1999-01-01

    In the renal proximal tubule, the activities of the basolateral Na+/HCO3– cotransporter (NBC) and the apical Na+/H+ exchanger (NHE3) uniformly vary in parallel, suggesting that they are coordinately regulated. PKA-mediated inhibition of NHE3 is mediated by a PDZ motif–containing protein, the Na+/H+ exchanger regulatory factor (NHE-RF). Given the common inhibition of these transporters after protein kinase A (PKA) activation, we sought to determine whether NHE-RF also plays a role in PKA-regulated NBC activity. Renal cortex immunoblot analysis using anti-peptide antibodies directed against rabbit NHE-RF demonstrated the presence of this regulatory factor in both brush-border membranes (BBMs) and basolateral membranes (BLMs). Using a reconstitution assay, we found that limited trypsin digestion of detergent solubilized rabbit renal BLM preparations resulted in NBC activity that was unaffected by PKA activation. Co-reconstitution of these trypsinized preparations with a recombinant protein corresponding to wild-type rabbit NHE-RF restored the inhibitory effect of PKA on NBC activity in a concentration-dependent manner. NBC activity was inhibited 60% by 10–8M NHE-RF; this effect was not observed in the absence of PKA. Reconstitution with heat-denatured NHE-RF also failed to attenuate NBC activity. To establish further a physiologic role for NHE-RF in NBC regulation, the renal epithelial cell line B-SC-1, which lacks detectable endogenous NHE-RF expression, was engineered to express stably an NHE-RF transgene. NHE-RF–expressing B-SC-1 cells (B-SC-RF) exhibited markedly lower basal levels of NBC activity than did wild-type controls. Inhibition of NBC activity in B-SC-RF cells was enhanced after 10 μM of forskolin treatment, consistent with a postulated role for NHE-RF in mediating the inhibition of NBC activity by PKA. These findings not only suggest NHE-RF involvement in PKA-regulated NBC activity, but also provide a unique molecular mechanism whereby

  16. Proteolytic Cleavage of ProBDNF into Mature BDNF in the Basolateral Amygdala Is Necessary for Defeat-Induced Social Avoidance

    Science.gov (United States)

    Dulka, Brooke N.; Ford, Ellen C.; Lee, Melissa A.; Donnell, Nathaniel J.; Goode, Travis D.; Prosser, Rebecca; Cooper, Matthew A.

    2016-01-01

    Brain-derived neurotrophic factor (BDNF) is essential for memory processes. The present study tested whether proteolytic cleavage of proBDNF into mature BDNF (mBDNF) within the basolateral amygdala (BLA) regulates the consolidation of defeat-related memories. We found that acute social defeat increases the expression of mBDNF, but not proBDNF, in…

  17. Oxytocin Signaling in Basolateral and Central Amygdala Nuclei Differentially Regulates the Acquisition, Expression, and Extinction of Context-Conditioned Fear in Rats

    Science.gov (United States)

    Campbell-Smith, Emma J.; Holmes, Nathan M.; Lingawi, Nura W.; Panayi, Marios C.; Westbrook, R. Frederick

    2015-01-01

    The present study investigated how oxytocin (OT) signaling in the central (CeA) and basolateral (BLA) amygdala affects acquisition, expression, and extinction of context-conditioned fear (freezing) in rats. In the first set of experiments, acquisition of fear to a shocked context was impaired by a preconditioning infusion of synthetic OT into the…

  18. Interaction between the Basolateral Amygdala and Dorsal Hippocampus Is Critical for Cocaine Memory Reconsolidation and Subsequent Drug Context-Induced Cocaine-Seeking Behaviorin Rats

    Science.gov (United States)

    Wells, Audrey M.; Lasseter, Heather C.; Xie, Xiaohu; Cowhey, Kate E.; Reittinger, Andrew M.; Fuchs, Rita A.

    2011-01-01

    Contextual stimulus control over instrumental drug-seeking behavior relies on the reconsolidation of context-response-drug associative memories into long-term memory storage following retrieval-induced destabilization. According to previous studies, the basolateral amygdala (BLA) and dorsal hippocampus (DH) regulate cocaine-related memory…

  19. The role of the amygdala in the extinction of conditioned fear.

    Science.gov (United States)

    Barad, Mark; Gean, Po-Wu; Lutz, Beat

    2006-08-15

    The amygdala has long been known to play a central role in the acquisition and expression of fear. More recently, convergent evidence has implicated the amygdala in the extinction of fear as well. In rodents, some of this evidence comes from the infusion of drugs directly into the amygdala and, in particular, into the basolateral complex of the amygdala, during or after extinction learning. In vivo electrophysiology has identified cellular correlates of extinction learning and memory in the lateral nucleus of that structure. Human imaging experiments also indicate that amygdaloid activity correlates with extinction training. In addition, some studies have directly identified changes in molecular constituents of the basolateral amygdala. Together these experiments strongly indicate that the basolateral amygdala plays a crucial role in extinction learning. Interpreted in the light of these findings, several recent in vitro electrophysiology studies in amygdala-containing brain slices are suggestive of potential synaptic and circuit bases of extinction learning.

  20. Long-term memory for pavlovian fear conditioning requires dopamine in the nucleus accumbens and basolateral amygdala.

    Directory of Open Access Journals (Sweden)

    Jonathan P Fadok

    Full Text Available The neurotransmitter dopamine (DA is essential for learning in a pavlovian fear conditioning paradigm known as fear-potentiated startle (FPS. Mice lacking the ability to synthesize DA fail to learn the association between the conditioned stimulus and the fear-inducing footshock. Previously, we demonstrated that restoration of DA synthesis to neurons of the ventral tegmental area (VTA was sufficient to restore FPS. Here, we used a target-selective viral restoration approach to determine which mesocorticolimbic brain regions receiving DA signaling from the VTA require DA for FPS. We demonstrate that restoration of DA synthesis to both the basolateral amygdala (BLA and nucleus accumbens (NAc is required for long-term memory of FPS. These data provide crucial insight into the dopamine-dependent circuitry involved in the formation of fear-related memory.

  1. Endomorphins exit the brain by a saturable efflux system at the basolateral surface of cerebral endothelial cells.

    Science.gov (United States)

    Somogyvari-Vigh, Aniko; Kastin, Abba J; Liao, Jie; Zadina, James E; Pan, Weihong

    2004-05-01

    Endomorphin-1 (EM-1) and endomorphin-2 (EM-2) are two highly selective mu-opiate receptor agonists. We recently demonstrated that EM-1 and EM-2 have a saturable transport system from brain-to-blood in vivo. Since the endothelial cells are the main component of the non-fenestrated microvessels of the blood-brain barrier (BBB), we examined whether these endogenous tetrapeptides have a saturable transport system in cultured cerebral endothelial cells. EM-1 and EM-2 binding and transport were studied in a transwell system in which primary mouse endothelial cells were co-cultured with rat glioma cells. We found that binding of both endomorphins was greater on the basolateral than the apical cell surface. Flux of EM-1 and EM-2 occurred predominantly in the basolateral to apical direction, each showing self-inhibition with an excess of the respective endomorphin. Transport was not influenced by the addition of the P-glycoprotein inhibitor, cyclosporin A. Neither the mu-opiate receptor agonist DAMGO nor the delta-opiate receptor agonist DPDPE had any effect on the transport. Thus, the results show that a saturable transport system for EM-1 and EM-2 occurs at the level of endothelial cells of the BBB, and unlike beta-endorphin and morphine, P-glycoprotein is not needed for the brain-to-blood transport. Cross-inhibition of the transport of each endomorphin by the other suggests a shared transport system that is different from mu- or delta-opiate receptors. As endormorphins are mainly produced in the CNS, the presence of the efflux system at the BBB could play an important role in pain modulation and neuroendocrine control.

  2. Dorsal Periaqueductal gray simultaneously modulates ventral Subiculum induced-plasticity in the Basolateral Amygdala and the Nucleus Accumbens

    Directory of Open Access Journals (Sweden)

    Omer eHorovitz

    2015-03-01

    Full Text Available The ventral subiculum of the hippocampus projects both to the basolateral amygdala, which is typically, associated with a response to aversive stimuli, as well as to the nucleus accumbens, which is typically associated with a response to appetitive stimuli. Traditionally, studies of the responses to emotional events focus on either negative or positive affect-related processes, however, emotional experiences often affect both. The ability of high-level processing brain regions (e.g. medial prefrontal cortex to modulate the balance between negative and positive affect-related regions was examined extensively. In contrast, the ability of low-level processing areas (e.g. periaqueductal grey - PAG to do so, has not been sufficiently studied. To address whether midbrain structures have the ability to modulate limbic regions, we first examined the ventral subiculum stimulation’s (vSub ability to induce plasticity in the basolateral amygdala (BLA and nucleus accumbens (NAcc simultaneously in rats. Further, dorsal PAG (dPAG priming ability to differentially modulate vSub stimulation induced plasticity in the BLA and the NAcc was subsequently examined. vSub stimulation resulted in plasticity in both the BLA and the NAcc simultaneously. Moreover, depending on stimulus intensity, differential dPAG priming effects on LTP in these two regions were observed. The results demonstrate that negative and positive affect-related processes may be simultaneously modulated. Furthermore, under some conditions lower-level processing areas, such as the dPAG, may differentially modulate plasticity in these regions and thus affect the long-term emotional outcome of the experience.

  3. Angiotensin II’s role in sodium lactate-induced panic-like responses in rats with repeated urocortin 1 injections into the basolateral amygdala

    OpenAIRE

    Johnson, Philip L.; Sajdyk, Tammy J.; Fitz, Stephanie D; Hale, Mathew W.; Lowry, Christopher A.; Hay-Schmidt, Anders; Shekhar, Anantha

    2013-01-01

    Rats treated with three daily urocortin 1 (UCN) injections into the basolateral amygdala (BLA; i.e., UCN/BLA-primed rats) develop prolonged anxiety-associated behavior and vulnerability to panic-like physiological responses (i.e., tachycardia, hypertension and tachypnea) following intravenous infusions of 0.5 M sodium lactate (NaLac, an ordinarily mild interoceptive stressor). In these UCN-primed rats, the osmosensitive subfornical organ (SFO) may be a potential site that detects increases in...

  4. Microtubule-dependent relocation of branchial V-H+-ATPase to the basolateral membrane in the Pacific spiny dogfish (Squalus acanthias): a role in base secretion.

    Science.gov (United States)

    Tresguerres, Martin; Parks, Scott K; Katoh, Fumi; Goss, Greg G

    2006-02-01

    We have previously shown that continuous intravenous infusion of NaHCO3 for 24 h ( approximately 1000 micromol kg(-1) h(-1)) results in the relocation of V-H+-ATPase from the cytoplasm to the basolateral membrane in the gills of the Pacific dogfish. To further investigate this putative base-secretive process we performed similar experiments with the addition of colchicine, an inhibitor of cytoskeleton-dependent cellular trafficking processes. Blood pH and plasma total CO2 were significantly higher in the colchicines-treated, HCO3- -infused fish compared with fish infused with HCO3- alone. The effect of colchicine was highest after 24 h of infusion (8.33+/-0.06 vs 8.02+/-0.03 pH units, 15.72+/-3.29 vs 6.74+/-1.34 mmol CO2 l(-1), N=5). Immunohistochemistry and western blotting confirmed that colchicine blocked the transit of V-H+-ATPase to the basolateral membrane. Furthermore, western blotting analyses from whole gill and cell membrane samples suggest that the short-term (6 h) response to alkaline stress consists of relocation of V-H+-ATPases already present in the cell to the basolateral membrane, while in the longer term (24 h) there is both relocation of preexistent enzyme and upregulation in the synthesis of new units. Our results strongly suggest that cellular relocation of V-H+-ATPase is necessary for enhanced HCO3- secretion across the gills of the Pacific dogfish.

  5. Basolateral sorting and transcytosis define the Cu+-regulated translocation of ATP7B to the bile canaliculus.

    Science.gov (United States)

    Lalioti, Vasiliki; Peiró, Ramón; Pérez-Berlanga, Manuela; Tsuchiya, Yo; Muñoz, Angeles; Villalba, Teresa; Sanchez, Carlos; Sandoval, Ignacio V

    2016-06-01

    The Cu(+) pump ATP7B plays an irreplaceable role in the elimination of excess Cu(+) by the hepatocyte into the bile. The trafficking and site of action of ATP7B are subjects of controversy. One current proposal is that an increase in intracellular Cu(+) results in the translocation of ATP7B to the lysosomes and excretion of excess Cu(+) through lysosomal-mediated exocytosis at the bile canaliculus. Here, we show that ATP7B is transported from the trans-Golgi network (TGN) to the bile canaliculus by basolateral sorting and endocytosis, and microtubule-mediated transcytosis through the subapical compartment. Trafficking ATP7B is not incorporated into lysosomes, and addition of Cu(+) does not cause relocalization of lysosomes and the appearance of lysosome markers in the bile canaliculus. Our data reveal the pathway of the Cu(+)-mediated transport of ATP7B from the TGN to the bile canaliculus and indicates that the bile canaliculus is the primary site of ATP7B action in the elimination of excess Cu(.)

  6. Infusion of methylphenidate into the basolateral nucleus of amygdala or anterior cingulate cortex enhances fear memory consolidation in rats

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The psychostimulant methylphenidate (MPD; also called Ritalin) is a blocker of dopamine and norepi-nephrine transporter. It has been clinically used for treatment of Attention Deficit and Hyperactivity Disorder (ADHD). There have been inconsistent reports regarding the effects of systemically adminis-tered MPD on learning and memory, either in animals or humans. In the present study, we investigated the effect of direct infusion of MPD into the basolateral nucleus of amygdala (BLA) or the anterior cin-gulate cortex (ACC) on conditioned fear memory. Rats were trained on a one-trial step-through inhibi-tory avoidance task. MPD was infused bilaterally into the BLA or the ACC, either at ‘0’ or 6 h post-training. Saline was administered as control. Memory retention was tested 48 h post-training. In-tra-BLA or intra-ACC infusion of MPD ‘0’ h but not 6 h post-training significantly improved 48-h memory retention: the MPD-treated rats had significant longer step-through latency than controls. The present results indicate that action of MPD in the BLA or the ACC produces a beneficial effect on the consoli-dation of inhibitory avoidance memory.

  7. Chronic cerebrolysin administration attenuates neuronal abnormalities in the basolateral amygdala induced by neonatal ventral hippocampus lesion in the rat.

    Science.gov (United States)

    Vázquez-Roque, Rubén Antonio; Ubhi, Kiren; Masliah, Eliezer; Flores, Gonzalo

    2014-01-01

    The neonatal ventral hippocampal lesion (nVHL) has emerged as a model of schizophrenia-related behavior in the rat. Our previous report demonstrated that cerebrolysin (Cbl), a neuropeptide preparation which mimics the action of endogenous neurotrophic factors on brain protection and repair, promoted recovery of dendritic and neuronal damage of the prefrontal cortex and nucleus accumbens and behavioral improvements in postpubertal nVHL rats. We recently demonstrated that nVHL animals exhibit dendritic atrophy and spine loss in the basolateral amygdala (BLA). This study aimed to determine whether Cbl treatment was capable of reducing BLA neuronal alterations observed in nVHL rats. The morphological evaluation included examination of dendrites using the Golgi-Cox procedure and stereology to quantify the total cell number in BLA. Golgi-Cox staining revealed that nVHL induced dendritic retraction and spine loss in BLA pyramidal neurons. Stereological analysis demonstrated nVHL also produced a reduction in cells in BLA. Interestingly, repeated Cbl treatment ameliorated dendritic pathology and neuronal loss in the BLA of the nVHL rats. Our data show that Cbl may foster recovery of BLA damage in postpubertal nVHL rats and suggests that the use of neurotrophic agents for the management of some schizophrenia-related symptoms may present an alternative therapeutic pathway in these disorders.

  8. Basolateral amygdala lesions attenuate safe taste memory-related c-fos expression in the rat perirhinal cortex.

    Science.gov (United States)

    Gómez-Chacón, Beatriz; Gámiz, Fernando; Gallo, Milagros

    2012-05-01

    Previous results indicated that damage and pharmacological inactivation of the basolateral amygdala (BLA) interfere with the attenuation of taste neophobia. A similar disruption of safe taste memories formation induced by the inhibition of protein synthesis in the perirhinal cortex (PRh) has been reported. Thus, we have assessed the effect of bilateral BLA neurotoxic lesions on PRh activity after novel and familiar taste exposure. Wistar male rats with NMDA lesions of the BLA and SHAM-operated received two consecutive exposures to a 3% cider vinegar solution. Fos-like immunoreactivity (FLI) was examined as a marker of neuronal activity in PRh. As expected the BLA lesioned group showed no evidence of neophobia attenuation. A similar number of PRh Fos-positive cells were found in SHAM and BLA groups exposed to the novel taste solution. However, the BLA-lesioned group exhibited a lower number of Fos stained cells than the SHAM-lesioned group after being exposed to the familiar taste solution. This supports the notion of BLA and PRh as components of a neural circuit involved in safe taste recognition memory and suggests a role of PRh in various forms of recognition memory.

  9. IGF-II receptors in luminal and basolateral membranes isolated from pars convoluta and pars recta of rabbit proximal tubule

    DEFF Research Database (Denmark)

    Jacobsen, Christian; Jessen, H; Flyvbjerg, A

    1995-01-01

    The binding of 125I-labeled insulin-like growth factor-II (125I-IGF-II) to luminal and basolateral membrane vesicles isolated from pars convoluta and the straight part (pars recta) of rabbit proximal tubule was investigated. Analyses of the binding data by use of the general stoichiometric binding...... equation revealed, that in all preparations IGF-II was bound to one high-affinity binding site and other sites with lower affinities. The specificity of the high-affinity 125I-IGF-II binding to the membrane vesicles assessed by displacement by unlabeled IGF-II, IGF-I and insulin showed that IGF-I displaced...... 125I-IGF-II in the range 22.5-47.9 nM (IC50) whereas insulin did not effect 125I-IGF-II binding at all. beta-Galactosidase inhibited the 125I-IGF-II binding with half-maximal inhibition of 20-30 nM beta-galactosidase. D-Mannose 6-phosphate increased the binding of 125I-IGF-II and reversed...

  10. Basolateral amygdala response to food cues in the absence of hunger is associated with weight gain susceptibility.

    Science.gov (United States)

    Sun, Xue; Kroemer, Nils B; Veldhuizen, Maria G; Babbs, Amanda E; de Araujo, Ivan E; Gitelman, Darren R; Sherwin, Robert S; Sinha, Rajita; Small, Dana M

    2015-05-20

    In rodents, food-predictive cues elicit eating in the absence of hunger (Weingarten, 1983). This behavior is disrupted by the disconnection of amygdala pathways to the lateral hypothalamus (Petrovich et al., 2002). Whether this circuit contributes to long-term weight gain is unknown. Using fMRI in 32 healthy individuals, we demonstrate here that the amygdala response to the taste of a milkshake when sated but not hungry positively predicts weight change. This effect is independent of sex, initial BMI, and total circulating ghrelin levels, but it is only present in individuals who do not carry a copy of the A1 allele of the Taq1A polymorphism. In contrast, A1 allele carriers, who have decreased D2 receptor density (Blum et al., 1996), show a positive association between caudate response and weight change. Regardless of genotype, however, dynamic causal modeling supports unidirectional gustatory input from basolateral amygdala (BLA) to hypothalamus in sated subjects. This finding suggests that, as in rodents, external cues gain access to the homeostatic control circuits of the human hypothalamus via the amygdala. In contrast, during hunger, gustatory inputs enter the hypothalamus and drive bidirectional connectivity with the amygdala. These findings implicate the BLA-hypothalamic circuit in long-term weight change related to nonhomeostatic eating and provide compelling evidence that distinct brain mechanisms confer susceptibility to weight gain depending upon individual differences in dopamine signaling.

  11. CRF1 receptor activation increases the response of neurons in the basolateral nucleus of the amygdala to afferent stimulation

    Directory of Open Access Journals (Sweden)

    2008-07-01

    Full Text Available The basolateral nucleus (BLA of the amygdala contributes to the consolidation of memories for emotional or stressful events. The nucleus contains a high density of CRF1 receptors that are activated by corticotropin-releasing factor (CRF. Modulation of the excitability of neurons in the BLA by CRF may regulate the immediate response to stressful events and the formation of associated memories. In the present study, CRF was found to increase the amplitude of field potentials recorded in the BLA following excitatory afferent stimulation, in vitro. The increase was mediated by CRF1 receptors, since it could be blocked by the selective, non-peptide antagonists, NBI30775 and NBI35583, but not by the CRF2-selective antagonist, astressin 2B. Furthermore, the CRF2-selective agonist, urocortin II had no effect on field potential amplitude. The increase induced by CRF was long-lasting, could not be reversed by subsequent administration of NBI35583, and required the activation of protein kinase C. This effect of CRF in the BLA may be important for increasing the salience of aversive stimuli under stressful conditions, and for enhancing the consolidation of associated memories. The results provide further justification for studying the efficacy of selective antagonists of the CRF1 receptor to reduce memory formation linked to emotional or traumatic events, and suggest that these compounds might be useful as prophylactic treatment for stress-related illness such as post-traumatic stress disorder.

  12. Inhibition of projections from the basolateral amygdala to the entorhinal cortex disrupts the acquisition of contextual fear

    Directory of Open Access Journals (Sweden)

    Dennis R. Sparta

    2014-05-01

    Full Text Available The development of excessive fear and/or stress responses to environmental cues such as contexts associated with a traumatic event is a hallmark of post-traumatic stress disorder (PTSD. The basolateral amygdala (BLA has been implicated as a key structure mediating contextual fear conditioning. In addition, the hippocampus has an integral role in the encoding and processing of contexts associated with strong, salient stimuli such as fear. Given that both the BLA and hippocampus play an important role in the regulation of contextual fear conditioning, examining the functional connectivity between these two structures may elucidate a role for this pathway in the development of PTSD. Here, we used optogenetic strategies to demonstrate that the BLA sends a strong glutamatergic projection to the hippocampal formation through the entorhinal cortex (EC. Next, we photoinhibited glutamatergic fibers from the BLA terminating in the EC during the acquisition or expression of contextual fear conditioning. In mice that received optical inhibition of the BLA-to-EC pathway during the acquisition session, we observed a significant decrease in freezing behavior in a context re-exposure session. In contrast, we observed no differences in freezing behavior in mice that were only photoinhibited during the context re-exposure session. These data demonstrate an important role for the BLA-to-EC glutamatergic pathway in the acquisition of contextual fear conditioning.

  13. The basolateral amygdala is critical to the expression of pavlovian and instrumental outcome-specific reinforcer devaluation effects.

    Science.gov (United States)

    Johnson, Alexander W; Gallagher, Michela; Holland, Peter C

    2009-01-21

    Considerable evidence implicates the basolateral amygdala (BLA) in the formation of outcome representations that link cues to the incentive properties of reinforcers. Animals with BLA damage show impaired performance in reinforcer devaluation tasks, in which the value of the food reinforcer is reduced by satiation or food-toxin pairings after the completion of cue or response training. Although intact animals spontaneously reduce their conditioned responding after such reinforcer devaluation procedures, animals with BLA lesions made before training typically do not, as evidenced across a range of species, training contingencies, and devaluation procedures. In contrast, the role of the BLA in devaluation task performance once such outcome representations are established is unclear. Whereas Pickens et al. (2003) found normal devaluation performance in rats when BLA lesions were made after pavlovian light-food pairings but before devaluation by food-toxin pairings, Ostlund and Balleine (2008) found impaired devaluation performance when BLA lesions were made after instrumental training with multiple instrumental responses and food reinforcers but before devaluation of one reinforcer by selective satiation. Those studies differed in their use of pavlovian or operant training contingencies, single or multiple reinforcers, and associative or motivational devaluation procedures. Here we found that, when multiple reinforcers were used, posttraining BLA lesions disrupted the expression of devaluation performance in rats, using either pavlovian or instrumental training procedures and either conditioned taste aversion or satiation devaluation procedures. Thus, BLA apparently plays a critical role in maintaining or using sensory associations of reinforcer value when multiple outcomes must be coded but not under single-outcome conditions.

  14. Dissociable roles for the basolateral amygdala and orbitofrontal cortex in decision-making under risk of punishment.

    Science.gov (United States)

    Orsini, Caitlin A; Trotta, Rose T; Bizon, Jennifer L; Setlow, Barry

    2015-01-28

    Several neuropsychiatric disorders are associated with abnormal decision-making involving risk of punishment, but the neural basis of this association remains poorly understood. Altered activity in brain systems including the basolateral amygdala (BLA) and orbitofrontal cortex (OFC) can accompany these same disorders, and these structures are implicated in some forms of decision-making. The current study investigated the role of the BLA and OFC in decision-making under risk of explicit punishment. Rats were trained in the risky decision-making task (RDT), in which they chose between two levers, one that delivered a small safe reward, and the other that delivered a large reward accompanied by varying risks of footshock punishment. Following training, they received sham or neurotoxic lesions of BLA or OFC, followed by RDT retesting. BLA lesions increased choice of the large risky reward (greater risk-taking) compared to both prelesion performance and sham controls. When reward magnitudes were equated, both BLA lesion and control groups shifted their choice to the safe (no shock) reward lever, indicating that the lesions did not impair punishment sensitivity. In contrast to BLA lesions, OFC lesions significantly decreased risk-taking compared with sham controls, but did not impair discrimination between different reward magnitudes or alter baseline levels of anxiety. Finally, neither lesion significantly affected food-motivated lever pressing under various fixed ratio schedules, indicating that lesion-induced alterations in risk-taking were not secondary to changes in appetitive motivation. Together, these findings indicate distinct roles for the BLA and OFC in decision-making under risk of explicit punishment.

  15. Unilateral inactivation of the basolateral amygdala attenuates context-induced renewal of Pavlovian-conditioned alcohol-seeking.

    Science.gov (United States)

    Chaudhri, N; Woods, C A; Sahuque, L L; Gill, T M; Janak, P H

    2013-09-01

    Environmental contexts associated with drug use promote craving in humans and drug-seeking in animals. We hypothesized that the basolateral amygdala (BLA) itself as well as serial connectivity between the BLA and nucleus accumbens core (NAC core) were required for context-induced renewal of Pavlovian-conditioned alcohol-seeking. Male Long-Evans rats were trained to discriminate between two conditioned stimuli (CS): a CS+ that was paired with ethanol (EtOH, 20%, v/v) delivery into a fluid port (0.2 mL/CS+, 3.2 mL per session) and a CS- that was not. Entries into the port during each CS were measured. Next, rats received extinction in a different context where both cues were presented without EtOH. At test, responding to the CS+ and CS- without EtOH was evaluated in the prior training context. Control subjects showed a selective increase in CS+ responding relative to extinction, indicative of renewal. This effect was blocked by pre-test, bilateral inactivation of the BLA using a solution of GABA receptor agonists (0.1 mm muscimol and 1.0 mm baclofen; M/B; 0.3 μL per side). Renewal was also attenuated following unilateral injections of M/B into the BLA, combined with either M/B, the dopamine D1 receptor antagonist SCH 23390 (0.6 μg per side) or saline infusion in the contralateral NAC core. Hence, unilateral BLA inactivation was sufficient to disrupt renewal, highlighting a critical role for functional activity in the BLA in enabling the reinstatement of alcohol-seeking driven by an alcohol context.

  16. β1-adrenoceptor activation is required for ethanol enhancement of lateral paracapsular GABAergic synapses in the rat basolateral amygdala.

    Science.gov (United States)

    Silberman, Yuval; Ariwodola, Olusegun J; Weiner, Jeff L

    2012-11-01

    Ethanol (EtOH) potentiation of GABAergic neurotransmission in the basolateral amygdala (BLA) may contribute to the acute anxiolytic effects of this drug. Previous studies have shown that BLA pyramidal neurons receive GABAergic input from two distinct sources: local interneurons and a cluster of GABAergic cells termed lateral paracapsular (LPCS) interneurons. It is noteworthy that whereas EtOH enhances local GABAergic synapses via a presynaptic increase in GABA release, EtOH potentiation of LPCS inhibition is mediated via a distinct mechanism that requires adrenoceptor (AR) activation. Here, we sought to further characterize the interaction between the AR system and EtOH enhancement of LPCS GABAergic synapses by using in vitro electrophysiology techniques in male Sprague-Dawley rats. Exogenous norepinephrine (NE) enhanced LPCS-evoked inhibitory postsynaptic currents (eIPSCs) via the activation of β-ARs, because this effect was blocked by propranolol. EtOH potentiation of LPCS eIPSCs was also blocked by propranolol and significantly reduced by NE pretreatment, suggesting that NE and EtOH may enhance LPCS inhibition via a common mechanism. EtOH enhancement of LPCS eIPSCs was significantly reduced by a selective β1-, but not β2- or β3-, AR antagonist, and both EtOH and NE potentiation of LPCS IPSCs was blocked by postsynaptic disruption of cAMP signaling. These data suggest that EtOH enhances LPCS synapses via a postsynaptic β1-AR, cAMP-dependent cascade. Because enhancement of LPCS inhibition can reduce anxiety-like behaviors, these findings shed light on a novel mechanism that may play a role in some of the anxiolytic effects of EtOH that are thought to contribute to the development and progression of alcoholism.

  17. Histamine acting on the basolateral amygdala reverts the impairment of aversive memory of rats submitted to neonatal maternal deprivation.

    Science.gov (United States)

    Benetti, Fernando; da Silveira, Clarice Kras Borges; Rosa, Jessica; Izquierdo, Ivan

    2015-02-01

    Recent findings suggest a role of brain histamine in the regulation of memory consolidation, particularly in one-trial inhibitory avoidance (IA) learning and that disruption in the mother infant relationship i.e. maternal deprivation induces cognitive deficits. We investigate whether histamine itself, and histaminergic compounds given into the basolateral amygdala (BLA) immediately post-training can affect retention (24 h after training) of one-trial (IA) in rats submitted to early postnatal maternal deprivation. In all cases, deprived (Dep) animals had lower retention scores than non-deprived controls (N-dep). Histamine induced memory enhancement on its own in N-dep animals and was able to overcome the deleterious effect of Dep. The effects by SKF-91488 is similar to histamine. The H3 agonist, imetit mimetized the enhancing effects of histamine; neither agonist H1 pyridylethylamine nor the H2 dimaprit had any effect. Ranitidine and thioperamide (50 nmol) co-infused with histamine (10 nmol) fully blocked the restorative effect of histamine on retention in Dep animals. Thioperamide, in addition, blocked the enhancing effect of histamine on memory of the N-dep animals as well. None of the drugs used given into BLA had any effect on open-field or elevated plus-maze behavior in N-dep or Dep rats. Our results are limited to experimental design in rats. Extrapolation i.e. in humans requires further experimentations. The present results suggest that the memory deficit induced by early postnatal maternal deprivation in rats may at least in part be due to an impairment of histamine H3 receptor-mediated mediated mechanisms in the BLA.

  18. Interactions between ethanol and the endocannabinoid system at GABAergic synapses on basolateral amygdala principal neurons.

    Science.gov (United States)

    Talani, Giuseppe; Lovinger, David M

    2015-12-01

    The basolateral amygdala (BLA) plays crucial roles in stimulus value coding, as well as drug and alcohol dependence. Ethanol alters synaptic transmission in the BLA, while endocannabinoids (eCBs) produce presynaptic depression at BLA synapses. Recent studies suggest interactions between ethanol and eCBs that have important consequences for alcohol drinking behavior. To determine how ethanol and eCBs interact in the BLA, we examined the physiology and pharmacology of GABAergic synapses onto BLA pyramidal neurons in neurons from young rats. Application of ethanol at concentrations relevant to intoxication increased, in both young and adult animals, the frequency of spontaneous and miniature GABAergic inhibitory postsynaptic currents, indicating a presynaptic site of ethanol action. Ethanol did not potentiate sIPSCs during inhibition of adenylyl cyclase while still exerting its effect during inhibition of protein kinase A. Activation of type 1 cannabinoid receptors (CB1) in the BLA inhibited GABAergic transmission via an apparent presynaptic mechanism, and prevented ethanol potentiation. Surprisingly, ethanol potentiation was also prevented by CB1 antagonists/inverse agonists. Brief depolarization of BLA pyramidal neurons suppressed GABAergic transmission (depolarization-induced suppression of inhibition [DSI]), an effect previously shown to be mediated by postsynaptic eCB release and presynaptic CB1 activation. A CB1-mediated suppression of GABAergic transmission was also produced by combined afferent stimulation at 0.1 Hz (LFS), and postsynaptic loading with the eCB arachidonoyl ethanolamide (AEA). Both DSI and LFS-induced synaptic depression were prevented by ethanol. Our findings indicate antagonistic interactions between ethanol and eCB/CB1 modulation at GABAergic BLA synapses that may contribute to eCB roles in ethanol seeking and drinking.

  19. Differential role of muscarinic transmission within the entorhinal cortex and basolateral amygdala in the processing of irrelevant stimuli.

    Science.gov (United States)

    Barak, Segev; Weiner, Ina

    2010-04-01

    Cholinergic projections to the entorhinal cortex (EC) and basolateral amygdala (BLA) mediate distinct cognitive processes through muscarinic acetylcholine receptors (mAChRs). In this study, we sought to further differentiate the role of muscarinic transmission in these regions in cognition, using the latent inhibition (LI) phenomenon. LI is a cross-species phenomenon manifested as poorer conditioning to a stimulus experienced as irrelevant during an earlier stage of repeated non-reinforced pre-exposure to that stimulus, and is considered to index the ability to ignore, or to in-attend to, irrelevant stimuli. Given our recent findings that systemic administration of the mAChR antagonist scopolamine can produce two contrasting LI abnormalities in rats, ie, abolish LI under conditions yielding LI in non-treated controls, or produce abnormally persistent LI under conditions preventing its expression in non-treated controls, we tested whether mAChR blockade in the EC and BLA would induce LI abolition and persistence, respectively. We found that intra-EC scopolamine infusion (1, 10 mug per hemisphere) abolished LI when infused in pre-exposure or both pre-exposure and conditioning, but not in conditioning alone, whereas intra-BLA scopolamine infusion led to persistent LI when infused in conditioning or both stages, but not in pre-exposure alone. Although cholinergic innervation of the EC and BLA has long been implicated in attention to novel stimuli and in processing of motivationally significant stimuli, respectively, our results provide evidence that EC mAChRs also have a role in the development of inattention to stimuli, whereas BLA mAChRs have a role in re-attending to previously irrelevant stimuli that became motivationally relevant.

  20. TRH and TRH receptor system in the basolateral amygdala mediate stress-induced depression-like behaviors.

    Science.gov (United States)

    Choi, Juli; Kim, Ji-eun; Kim, Tae-Kyung; Park, Jin-Young; Lee, Jung-Eun; Kim, Hannah; Lee, Eun-Hwa; Han, Pyung-Lim

    2015-10-01

    Chronic stress is a potent risk factor for depression, but the mechanism by which stress causes depression is not fully understood. To investigate the molecular mechanism underlying stress-induced depression, C57BL/6 inbred mice were treated with repeated restraint to induce lasting depressive behavioral changes. Behavioral states of individual animals were evaluated using the forced swim test, which measures psychomotor withdrawals, and the U-field test, which measures sociability. From these behavioral analyses, individual mice that showed depression-like behaviors in both psychomotor withdrawal and sociability tests, and individuals that showed a resiliency to stress-induced depression in both tests were selected. Among the neuropeptides expressed in the amygdala, thyrotropin-releasing hormone (TRH) was identified as being persistently up-regulated in the basolateral amygdala (BLA) in individuals exhibiting severe depressive behaviors in the two behavior tests, but not in individuals displaying a stress resiliency. Activation of TRH receptors by local injection of TRH in the BLA in normal mice produced depressive behaviors, mimicking chronic stress effects, whereas siRNA-mediated suppression of either TRH or TRHR1 in the BLA completely blocked stress-induced depressive symptoms. The TRHR1 agonist, taltirelin, injection in the BLA increased the level of p-ERK, which mimicked the increased p-ERK level in the BLA that was induced by treatment with repeated stress. Stereotaxic injection of U0126, a potent inhibitor of the ERK pathway, within the BLA blocked stress-induced behavioral depression. These results suggest that repeated stress produces lasting depression-like behaviors via the up-regulation of TRH and TRH receptors in the BLA.

  1. Distribution of gamma-aminobutyric and nitrogen monoxide-coexisting neurons in cortical amygdaloid nucleus in rats and its modulation effect on pain transmission%大鼠杏仁皮质核内γ-氨基丁酸与一氧化氮共存神经元分布及对痛觉信息传递的调控

    Institute of Scientific and Technical Information of China (English)

    倪晶晶; 凌树才; 朱晞

    2005-01-01

    BACKGROUND: Quite a few deoxidized reduced form of nicotinamide-adenime dinucleotide phosphate (NADPH-d) -positive neurons distribute in amygdala complex (AMC) and gamma-aminobutyric acid(GABA)is an important inhibitory neurotransmitter that also widely distributes in the central nervous system (CNS) of mammals. Whether there is coexistence of GABA and nitricoxide synthase (NOS) in AMC is unknown at present.OBJECTIVE: To observe whether there is GABA and NADPH-d-eoexist neuron in cortical nucleus of amygdala (Co) with the combination of NADPH-d hischemical and immunohistochemical double staining.DESIGN: A verifying controlled study based on the experimental animals.SETTING: Department of anatomy of two universities MATERIALS: The study was conducted in the department of Anatomy,Medical College of Zhejiang University between May 2004 and June 2004. Six SD rats in either gender with a body mass between 250 g and 300 g were selected.INTERVENTIONS: Coronary serial frozen slices of brain tissue were prepared. 4 sets of slices were selected for Nissl staining, NADPH-d histochemical staining, NADPH-d histochemical and GABA immunohistochemical double staining, and control experiment for the test of antibody specificity. GABA-labeled neurons, NADPH-d-positive neurons, and NADPH-d/GABA double-labeled neurons were counted in Co nucleus for the calculation of the percentage of double-labeled positive neurons to single-labeled positive neurons.MAIN OUTCOME MEASURES: Distribution of NADPH-d/GABA double labeled neuron; distribution of NADPH-d or GABA single labeled neuron.RESULTS: Most of GABA-positive neurons distributed in posteromed cortical amygdaloid nucleus (PMCo), posterolateral cortical amygdaloid nucleus (PLCo), which were mainly small types but few middle types. Most of NADPH-d-positive neurons distributed in PMCo, PLCo and anterior cortical amygdaloid nucleus (Aco), which were mainly middle sized and small sized neurons. The ratio of NADPH-d/GABA double-labeled neurons

  2. Berberine Reduces cAMP-Induced Chloride Secretion in T84 Human Colonic Carcinoma Cells through Inhibition of Basolateral KCNQ1 Channels.

    LENUS (Irish Health Repository)

    Alzamora, Rodrigo

    2011-01-01

    Berberine is a plant alkaloid with multiple pharmacological actions, including antidiarrhoeal activity and has been shown to inhibit Cl(-) secretion in distal colon. The aims of this study were to determine the molecular signaling mechanisms of action of berberine on Cl(-) secretion and the ion transporter targets. Monolayers of T84 human colonic carcinoma cells grown in permeable supports were placed in Ussing chambers and short-circuit current measured in response to secretagogues and berberine. Whole-cell current recordings were performed in T84 cells using the patch-clamp technique. Berberine decreased forskolin-induced short-circuit current in a concentration-dependent manner (IC(50) 80 ± 8 μM). In apically permeabilized monolayers and whole-cell current recordings, berberine inhibited a cAMP-dependent and chromanol 293B-sensitive basolateral membrane K(+) current by 88%, suggesting inhibition of KCNQ1 K(+) channels. Berberine did not affect either apical Cl(-) conductance or basolateral Na(+)-K(+)-ATPase activity. Berberine stimulated p38 MAPK, PKCα and PKA, but had no effect on p42\\/p44 MAPK and PKCδ. However, berberine pre-treatment prevented stimulation of p42\\/p44 MAPK by epidermal growth factor. The inhibitory effect of berberine on Cl(-) secretion was partially blocked by HBDDE (∼65%), an inhibitor of PKCα and to a smaller extent by inhibition of p38 MAPK with SB202190 (∼15%). Berberine treatment induced an increase in association between PKCα and PKA with KCNQ1 and produced phosphorylation of the channel. We conclude that berberine exerts its inhibitory effect on colonic Cl(-) secretion through inhibition of basolateral KCNQ1 channels responsible for K(+) recycling via a PKCα-dependent pathway.

  3. Berberine Reduces cAMP-Induced Chloride Secretion in T84 Human Colonic Carcinoma Cells through Inhibition of Basolateral KCNQ1 Channels.

    LENUS (Irish Health Repository)

    Alzamora, Rodrigo

    2012-02-01

    Berberine is a plant alkaloid with multiple pharmacological actions, including antidiarrhoeal activity and has been shown to inhibit Cl(-) secretion in distal colon. The aims of this study were to determine the molecular signaling mechanisms of action of berberine on Cl(-) secretion and the ion transporter targets. Monolayers of T84 human colonic carcinoma cells grown in permeable supports were placed in Ussing chambers and short-circuit current measured in response to secretagogues and berberine. Whole-cell current recordings were performed in T84 cells using the patch-clamp technique. Berberine decreased forskolin-induced short-circuit current in a concentration-dependent manner (IC(50) 80 +\\/- 8 muM). In apically permeabilized monolayers and whole-cell current recordings, berberine inhibited a cAMP-dependent and chromanol 293B-sensitive basolateral membrane K(+) current by 88%, suggesting inhibition of KCNQ1 K(+) channels. Berberine did not affect either apical Cl(-) conductance or basolateral Na(+)-K(+)-ATPase activity. Berberine stimulated p38 MAPK, PKCalpha and PKA, but had no effect on p42\\/p44 MAPK and PKCdelta. However, berberine pre-treatment prevented stimulation of p42\\/p44 MAPK by epidermal growth factor. The inhibitory effect of berberine on Cl(-) secretion was partially blocked by HBDDE ( approximately 65%), an inhibitor of PKCalpha and to a smaller extent by inhibition of p38 MAPK with SB202190 ( approximately 15%). Berberine treatment induced an increase in association between PKCalpha and PKA with KCNQ1 and produced phosphorylation of the channel. We conclude that berberine exerts its inhibitory effect on colonic Cl(-) secretion through inhibition of basolateral KCNQ1 channels responsible for K(+) recycling via a PKCalpha-dependent pathway.

  4. Berberine reduces cAMP-induced chloride secretion in T84 human colonic carcinoma cells through inhibition of basolateral KCNQ1 channels

    Directory of Open Access Journals (Sweden)

    Rodrigo eAlzamora

    2011-06-01

    Full Text Available Berberine is a plant alkaloid with multiple pharmacological actions, including antidiarrhoeal activity and has been shown to inhibit Cl- secretion in distal colon. The aims of this study were to determine the molecular signalling mechanisms of action of berberine on Cl- secretion and the ion transporter targets. Monolayers of T84 human colonic carcinoma cells grown in permeable supports were placed in Ussing chambers and short-circuit current measured in response to secretagogues and berberine. Whole-cell current recordings were performed in T84 cells using the patch-clamp technique. Berberine decreased forskolin-induced short-circuit current in a concentration-dependent manner (IC50 80  8 M. In apically permeabilized monolayers and whole-cell current recordings, berberine inhibited a cAMP-dependent and chromanol 293B-sensitive basolateral membrane K+ current by 88%, suggesting inhibition of KCNQ1 K+ channels. Berberine did not affect either apical Cl- conductance or basolateral Na+-K+-ATPase activity. Berberine stimulated p38 MAPK, PKC and PKA, but had no effect on p42/p44 MAPK and PKC. However, berberine pre-treatment prevented stimulation of p42/p44 MAPK by epidermal growth factor. The inhibitory effect of berberine on Cl- secretion was partially blocked by HBDDE (65 %, an inhibitor of PKC and to a smaller extent by inhibition of p38 MAPK with SB202190 (15 %. Berberine treatment induced an increase in association between PKC and PKA with KCNQ1 and produced phosphorylation of the channel. We conclude that berberine exerts its inhibitory effect on colonic Cl- secretion through inhibition of basolateral KCNQ1 channels responsible for K+ recycling via a PKC-dependent pathway.

  5. Localization of the CB1 type cannabinoid receptor in the rat basolateral amygdala: high concentrations in a subpopulation of cholecystokinin-containing interneurons.

    Science.gov (United States)

    McDonald, A J; Mascagni, F

    2001-01-01

    The neuronal localization of the CB1 cannabinoid receptor in the rat basolateral amygdala was studied using peroxidase and fluorescence immunohistochemical techniques. All nuclei of the basolateral amygdala contained a large number of lightly stained pyramidal neurons and a small number of more intensely stained non-pyramidal neurons. Most of the latter cells had medium-sized to large multipolar somata and three to four aspiny dendrites, but some exhibited smaller oval somata. The axon initial segments of some of these non-pyramidal neurons exhibited large swollen varicosities in colchicine-injected animals, suggesting that much of the CB1 receptor protein is transported down the axons of these cells. Double-labeling studies using immunofluorescence histochemistry combined with confocal laser scanning microscopy revealed that the great majority of non-pyramidal neurons with CB1 receptor immunoreactivity belonged to a cholecystokinin-containing subpopulation. Whereas none of the other subpopulations of non-pyramidal neurons (exhibiting immunoreactivity for calretinin, parvalbumin, or somatostatin) expressed high levels of CB1 receptor immunoreactivity, a small percentage of these cells exhibited low levels of immunoreactivity. The results indicate that cannabinoids may modulate the activity of pyramidal projection neurons as well as a subpopulation of cholecystokinin-containing non-pyramidal neurons in the basolateral amygdala. Previous studies indicate that most of the latter are inhibitory interneurons that utilize GABA as a neurotransmitter. The intense staining of the cholecystokinin-containing interneurons and the evidence that large amounts of CB1 receptor protein are transported down the axons of these cells suggests that, as in the hippocampus, cannabinoids may inhibit the release of GABA from the axon terminals of these neurons.

  6. Ketamine prevents lidocaine-caused neurotoxicity in the CA3 hippocampal and basolateral amygdala regions of the brain in adult rats.

    Science.gov (United States)

    Lopez-Galindo, Gabriel Eduardo; Cano-Europa, Edgar; Ortiz-Butron, Rocio

    2008-01-01

    Our objective was to prove whether blocking the action of glutamate on N-methyl-D: -aspartate (NMDA) receptors could prevent the neuronal damage caused by the acute administration of lidocaine. Twenty male 2-month-old Wistar rats were randomly assigned to the following groups (n = 5 in each group): groups I and II received 0.9% saline i.p., and groups III and IV received 100 mg x kg(-1) of ketamine i.p. Thirty minutes later, groups I and III were again dosed with 0.9% saline i.p., and groups II and IV received 60 mg x kg(-1) of lidocaine i.p. During treatment, the rectal temperature of the animals was monitored and maintained at 37.5 +/- 0.5 degrees C. Ten days after administration of the agents, all rats were transcardially perfused, under pentobarbital anesthesia, with 10% formaldehyde. Their brains were removed and were embedded in paraffin. Coronal cuts of 7 microm were obtained from -2.3 to -3.8 mm from the bregma. Each brain section was stained with cresyl violet-eosin. The number of normal and abnormal pyramidal neurons in the CA3 hippocampal region and the number of large and medium neurons in the basolateral amygdala within an area of 10 000 microm2 were evaluated. We found that lidocaine significantly reduced the number of normal neurons in both the CA3 hippocampal region (F (3,16) = 225.8; P lidocaine-induced damage in the CA3 hippocampal region and the basolateral amygdala. These results demonstrate the participation of NMDA-receptor activation by lidocaine in the CA3 hippocampal and basolateral amygdala regions as a neurotoxic mechanism.

  7. Low dose prenatal ethanol exposure induces anxiety-like behaviour and alters dendritic morphology in the basolateral amygdala of rat offspring.

    Directory of Open Access Journals (Sweden)

    Carlie L Cullen

    Full Text Available Prenatal exposure to high levels of alcohol is strongly associated with poor cognitive outcomes particularly in relation to learning and memory. It is also becoming more evident that anxiety disorders and anxiety-like behaviour can be associated with prenatal alcohol exposure. This study used a rat model to determine if prenatal exposure to a relatively small amount of alcohol would result in anxiety-like behaviour and to determine if this was associated with morphological changes in the basolateral amygdala. Pregnant Sprague Dawley rats were fed a liquid diet containing either no alcohol (Control or 6% (vol/vol ethanol (EtOH throughout gestation. Male and Female offspring underwent behavioural testing at 8 months (Adult or 15 months (Aged of age. Rats were perfusion fixed and brains were collected at the end of behavioural testing for morphological analysis of pyramidal neuron number and dendritic morphology within the basolateral amygdala. EtOH exposed offspring displayed anxiety-like behaviour in the elevated plus maze, holeboard and emergence tests. Although sexually dimorphic behaviour was apparent, sex did not impact anxiety-like behaviour induced by prenatal alcohol exposure. This increase in anxiety - like behaviour could not be attributed to a change in pyramidal cell number within the BLA but rather was associated with an increase in dendritic spines along the apical dendrite which is indicative of an increase in synaptic connectivity and activity within these neurons. This study is the first to link increases in anxiety like behaviour to structural changes within the basolateral amygdala in a model of prenatal ethanol exposure. In addition, this study has shown that exposure to even a relatively small amount of alcohol during development leads to long term alterations in anxiety-like behaviour.

  8. Cooperative interaction between the basolateral amygdala and ventral tegmental area modulates the consolidation of inhibitory avoidance memory.

    Science.gov (United States)

    Nazari-Serenjeh, Farzaneh; Rezayof, Ameneh

    2013-01-10

    The aim of the current study was to examine the existence of a cooperative interaction between the basolateral nucleus of amygdala (BLA) and the ventral tegmental area (VTA) in inhibitory avoidance task. The BLA and the VTA regions of adult male Wistar rats were simultaneously cannulated and memory consolidation was measured in a step-through type inhibitory avoidance apparatus. Post-training microinjection of muscimol, a potent GABA-A receptor agonist (0.01-0.02 μg/rat), into the VTA impaired memory in a dose-dependent manner. Post-training intra-BLA microinjection of NMDA (0.02-0.04 μg/rat), 5 min before the intra-VTA injection of muscimol (0.02 μg/rat), attenuated muscimol-induced memory impairment. Microinjection of a NMDA receptor antagonist, D-AP5 (0.02-0.06 μg/rat) into the BLA inhibited NMDA effect on the memory impairment induced by intra-VTA microinjection of muscimol. On the other hand, post-training intra-BLA microinjection of muscimol (0.02-0.04 μg/rat) dose-dependently decreased step-through latency, indicating an impairing effect on memory. This impairing effect was however significantly attenuated by intra-VTA microinjection of NMDA (0.01-0.03 μg/rat). Intra-VTA microinjection of D-AP5 (0.02-0.08 μg/rat), 5 min prior to NMDA injection, inhibited NMDA response on the impairing effect induced by intra-BLA microinjection of muscimol. It should be considered that post-training microinjection of the same doses of NMDA or D-AP5 into the BLA or the VTA alone had no effect on memory consolidation. The data suggest that the relationship between the BLA and the VTA in mediating memory consolidation in inhibitory avoidance learning may be dependent on a cooperative interaction between the glutamatergic and GABAergic systems via NMDA and GABA-A receptors.

  9. Activation of the basolateral amygdala induces long-term enhancement of specific memory representations in the cerebral cortex.

    Science.gov (United States)

    Chavez, Candice M; McGaugh, James L; Weinberger, Norman M

    2013-03-01

    The basolateral amygdala (BLA) modulates memory, particularly for arousing or emotional events, during post-training periods of consolidation. It strengthens memories whose substrates in part or whole are stored remotely, in structures such as the hippocampus, striatum and cerebral cortex. However, the mechanisms by which the BLA influences distant memory traces are unknown, largely because of the need for identifiable target mnemonic representations. Associative tuning plasticity in the primary auditory cortex (A1) constitutes a well-characterized candidate specific memory substrate that is ubiquitous across species, tasks and motivational states. When tone predicts reinforcement, the tuning of cells in A1 shifts toward or to the signal frequency within its tonotopic map, producing an over-representation of behaviorally important sounds. Tuning shifts have the cardinal attributes of forms of memory, including associativity, specificity, rapid induction, consolidation and long-term retention and are therefore likely memory representations. We hypothesized that the BLA strengthens memories by increasing their cortical representations. We recorded multiple unit activity from A1 of rats that received a single discrimination training session in which two tones (2.0 s) separated by 1.25 octaves were either paired with brief electrical stimulation (400 ms) of the BLA (CS+) or not (CS-). Frequency response areas generated by presenting a matrix of test tones (0.5-53.82 kHz, 0-70 dB) were obtained before training and daily for 3 weeks post-training. Tuning both at threshold and above threshold shifted predominantly toward the CS+ beginning on day 1. Tuning shifts were maintained for the entire 3 weeks. Absolute threshold and bandwidth decreased, producing less enduring increases in sensitivity and selectivity. BLA-induced tuning shifts were associative, highly specific and long-lasting. We propose that the BLA strengthens memory for important experiences by increasing the

  10. Proteins involved in uptake, intracellular transport and basolateral secretion of fat-soluble vitamins and carotenoids by mammalian enterocytes.

    Science.gov (United States)

    Reboul, Emmanuelle; Borel, Patrick

    2011-10-01

    Our understanding of the molecular mechanisms responsible for fat-soluble vitamin uptake and transport at the intestinal level has advanced considerably over the past decade. On one hand, it has long been considered that vitamin D and E as well as β-carotene (the main provitamin A carotenoid in human diet) were absorbed by a passive diffusion process, although this could not explain the broad inter-individual variability in the absorption efficiency of these molecules. On the other hand, it was assumed that preformed vitamin A (retinol) and vitamin K1 (phylloquinone) absorption occurred via energy-dependent processes, but the transporters involved have not yet been identified. The recent discovery of intestinal proteins able to facilitate vitamin E and carotenoid uptake and secretion by the enterocyte has spurred renewed interest in studying the fundamental mechanisms involved in the absorption of these micronutrients. The proteins identified so far are cholesterol transporters such as SR-BI (scavenger receptor class B type I), CD36 (cluster determinant 36), NPC1L1 (Niemann-Pick C1-like 1) or ABCA1 (ATP-Binding Cassette A1) displaying a broad substrate specificity, but it is likely that other membrane proteins are also involved. After overviewing the metabolism of fat-soluble vitamins and carotenoids in the human upper gastrointestinal lumen, we will focus on the putative or identified proteins participating in the intestinal uptake, intracellular transport and basolateral secretion of these fat-soluble vitamins and carotenoids, and outline the uncertainties that need to be explored in the future. Identifying the proteins involved in intestinal uptake and transport of fat-soluble vitamins and carotenoids across the enterocyte is of great importance, especially as some of them are already targets for the development of drugs able to slow cholesterol absorption. Indeed, these drugs may also interfere with lipid vitamin uptake. A better understanding of the molecular

  11. Functional lateralization of the baso-lateral amygdala neural circuits modulating the motivated exploratory behaviour in rats: role of histamine.

    Science.gov (United States)

    Alvarez, Edgardo O; Banzan, Arturo M

    2011-03-17

    Functional laterality appears to be present in many brain functions in man and animals. The existence of paired neural circuits which act differentially to modulate a specific behavioural function seems to be an evolutionary successful strategy in animal evolution. In spite of many examples described in mammals, birds and other vertebrates and invertebrates, still its intrinsic mechanism is not completely understood. In this work the participation of the baso-lateral amygdala (BLA) on lateralized motivated exploratory behaviour and the possible influence of histamine neurons in these mechanisms were studied in rats. Different groups of animals under xylacine-ketamine anesthesia were implanted with microinjection guide cannulae into the right or left BLA. 72 h after implantation, animals were tested in hole-board cage (OVM) with a novelty object positioned in the center of the arena, as a model of exploration of a non-conflictive environment, and 24h later they were tested in the Elevated Asymmetric Plus Maze (APM) as a model of conflictive exploration. In the day of the experiment, lidocaine was applied into the left, or right BLA in order to block the electrical activity of BLA neurons. Saline in the contralateral BLA was considered control. Results showed that exploratory activity in the OVM was significantly inhibited when lidocaine was microinjected into the left BLA, and no changes were observed when lidocaine was applied into the right BLA. When histamine was microinjected into the right BLA and lidocaine into the contralateral BLA, head-dipping, rearing, and focalized exploration behaviour were significantly inhibited. In the APM, lidocaine treatment increased equally the exploration of the "single wall" and "high and low walls" arms of the labyrinth, independently if blocking of electrical activity of the BLA neurons was performed in the left or right amygdala. Histamine treatment inhibited significantly exploration of the lesser fear-inducing arms of the

  12. Discerning apical and basolateral properties of HT-29/B6 and IPEC-J2 cell layers by impedance spectroscopy, mathematical modeling and machine learning.

    Directory of Open Access Journals (Sweden)

    Thomas Schmid

    Full Text Available Quantifying changes in partial resistances of epithelial barriers in vitro is a challenging and time-consuming task in physiology and pathophysiology. Here, we demonstrate that electrical properties of epithelial barriers can be estimated reliably by combining impedance spectroscopy measurements, mathematical modeling and machine learning algorithms. Conventional impedance spectroscopy is often used to estimate epithelial capacitance as well as epithelial and subepithelial resistance. Based on this, the more refined two-path impedance spectroscopy makes it possible to further distinguish transcellular and paracellular resistances. In a next step, transcellular properties may be further divided into their apical and basolateral components. The accuracy of these derived values, however, strongly depends on the accuracy of the initial estimates. To obtain adequate accuracy in estimating subepithelial and epithelial resistance, artificial neural networks were trained to estimate these parameters from model impedance spectra. Spectra that reflect behavior of either HT-29/B6 or IPEC-J2 cells as well as the data scatter intrinsic to the used experimental setup were created computationally. To prove the proposed approach, reliability of the estimations was assessed with both modeled and measured impedance spectra. Transcellular and paracellular resistances obtained by such neural network-enhanced two-path impedance spectroscopy are shown to be sufficiently reliable to derive the underlying apical and basolateral resistances and capacitances. As an exemplary perturbation of pathophysiological importance, the effect of forskolin on the apical resistance of HT-29/B6 cells was quantified.

  13. Functional disconnection of the orbitofrontal cortex and basolateral amygdala impairs acquisition of a rat gambling task and disrupts animals' ability to alter decision-making behavior after reinforcer devaluation.

    Science.gov (United States)

    Zeeb, Fiona D; Winstanley, Catharine A

    2013-04-10

    An inability to adjust choice preferences in response to changes in reward value may underlie key symptoms of many psychiatric disorders, including chemical and behavioral addictions. We developed the rat gambling task (rGT) to investigate the neurobiology underlying complex decision-making processes. As in the Iowa Gambling task, the optimal strategy is to avoid choosing larger, riskier rewards and to instead favor options associated with smaller rewards but less loss and, ultimately, greater long-term gain. Given the demonstrated importance of the orbitofrontal cortex (OFC) and basolateral amygdala (BLA) in acquisition of the rGT and Iowa Gambling task, we used a contralateral disconnection lesion procedure to assess whether functional connectivity between these regions is necessary for optimal decision-making. Disrupting the OFC-BLA pathway retarded acquisition of the rGT. Devaluing the reinforcer by inducing sensory-specific satiety altered decision-making in control groups. In contrast, disconnected rats did not update their choice preference following reward devaluation, either when the devalued reward was still delivered or when animals needed to rely on stored representations of reward value (i.e., during extinction). However, all rats exhibited decreased premature responding and slower response latencies after satiety manipulations. Hence, disconnecting the OFC and BLA did not affect general behavioral changes caused by reduced motivation, but instead prevented alterations in the value of a specific reward from contributing appropriately to cost-benefit decision-making. These results highlight the role of the OFC-BLA pathway in the decision-making process and suggest that communication between these areas is vital for the appropriate assessment of reward value to influence choice.

  14. Virus interaction with the apical junctional complex.

    Science.gov (United States)

    Gonzalez-Mariscal, Lorenza; Garay, Erika; Lechuga, Susana

    2009-01-01

    In order to infect pathogens must breach the epithelial barriers that separate the organism from the external environment or that cover the internal cavities and ducts of the body. Epithelia seal the passage through the paracellular pathway with the apical junctional complex integrated by tight and adherens junctions. In this review we describe how viruses like coxsackie, swine vesicular disease virus, adenovirus, reovirus, feline calcivirus, herpes viruses 1 and 2, pseudorabies, bovine herpes virus 1, poliovirus and hepatitis C use as cellular receptors integral proteins present at the AJC of epithelial cells. Interaction with these proteins contributes in a significant manner in defining the particular tropism of each virus. Besides these proteins, viruses exhibit a wide range of cellular co-receptors among which proteins present in the basolateral cell surface like integrins are often found. Therefore targeting proteins of the AJC constitutes a strategy that might allow viruses to bypass the physical barrier that blocks their access to receptors expressed on the basolateral surface of epithelial cells.

  15. Biosynthesis of intestinal microvillar proteins. Evidence for an intracellular sorting taking place in, or shortly after, exit from the Golgi complex

    DEFF Research Database (Denmark)

    Danielsen, E M; Cowell, G M

    1985-01-01

    the Mg2+-precipitated fraction were equally well protected from proteolytic cleavage (in the absence of Triton X-100). This indicates that the basolateral plasma membrane is unlikely to be involved in the post-Golgi transport of newly synthesized aminopeptidase N and suggests instead a direct delivery...... that for microvillar enzymes, the aspects of sorting studied take place in, or shortly after exit from, the Golgi complex....

  16. Effect of glandular kallikrein on distal bicarbonate transport. Role of basolateral Cl-/HCO3- exchanger and vacuolar H(+)-ATPase.

    Science.gov (United States)

    Manucha, W; Vallés, P

    1999-12-01

    The luminal membrane of collecting duct cells, specially the intercalated cells, is normally exposed to active kallikrein. This is due to the specific localization of renal kallikrein in the connecting tubule cells. We have previously reported inhibition of distal bicarbonate secretion by renal kallikrein. The present study was performed to evaluate the participation of basolateral Cl-/HCO3- exchanger and luminal H(+)-ATPase activity of cortical collecting duct segments (CCD) in the mechanism involved in the inhibition of bicarbonate secretion induced by the enzyme. The effect of orthograde injections of 1 microgram/ml (250 U/6.3 mg) pig pancreatic kallikrein, in the absence and presence of 1 mM DIDS (stilbene-disulfonic acid) in the renal tubule system, was evaluated. Urine fractions were collected after two-minutes stop-flow. Changes in the urine fraction (Fr) related to those in free-flow urine samples (Ff) were related to the respective polyfructosan (Inutest) ratio. Renal kallikrein activity (Fr:Ff kallikrein/Fr:Ff polyfructosan) increased significantly in the first 120 microliters urine fraction collected after glandular 1 microgram/ml kallikrein, P Bicarbonate secretion rate (Fr:Ff HCO3-/Fr:Ff polyfructosan) of collecting ducts was significantly reduced in the first 120 microliters urine fraction collected, related to control, during the first and second stop-flow periods. No difference was shown in bicarbonate excretion between the first 120 microliters urine fractions collected after administration of glandular kallikrein and glandular kallikrein plus DIDS. To measure H(+)-ATPase activity, rat microdissected cortical collector tubules (CCD) were incubated in the presence of increasing glandular kallikrein doses (A: 93, B: 187 and C: 375 mU/200 microL) in the presence of ouabain (4 microM) and omeprazole (100 microM) to inhibit Na(+)-K(+)-ATPase and H(+)-K(+)-ATPase, respectively. In CCD, bafilomycin-sensitive H(+)-ATPase activity (pmol/mm/min) after

  17. Distinctive roles of 5-Aza-2′-deoxycytidine in Anterior Agranular Insular and Basolateral Amygdala in Reconsolidation of aversive memory associated with Morphine in Rats

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    Peng eLiu

    2016-03-01

    Full Text Available 5-aza-2-deoxycytidine (5-aza, an inhibitor of DNA methyltransferases (DNMTs, has been implicated in aversive memory and the function of brain region which processing affect. However, little is known about the role of 5-aza in the reconsolidation of opiate withdrawal memory. In the present study, using the morphine-naloxone induced conditioned place aversion (CPA model in rats, we injected 5-aza into agranular insular (AI, granular insular (GI, basolateral amygdala (BLA and central amygdala (CeA immediately after the memory retrieval and tested the behavioral consequences at 24hours, 7 days and 14days after retrieval test. We found that 5-aza injection into AI disrupted the reconsolidation of morphine-associated withdrawal memory, but 5-aza injection into GI had no impact on the reconsolidation. Meanwhile, 5-aza injection into BLA but not CeA attenuated the withdrawal memory trace 14 days later. However, 5-aza administration to rats, in the absence of memory reactivation, had no effect on morphine-associated withdrawal memory. These findings suggest that 5-aza interfere with the reconsolidation of opiate withdrawal memory, and the roles of insular and amygdala in reconsolidation are distinctive.

  18. Lesions of basolateral amygdala impair extinction of CS motivational value, but not of explicit conditioned responses, in Pavlovian appetitive second-order conditioning.

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    Lindgren, John L; Gallagher, Michela; Holland, Peter C

    2003-01-01

    The basolateral amygdala (BLA) is important for the modification of the motivational significance of events through associative learning. In previous work, we found that BLA was critical for the acquisition of conditioned reinforcement value to a visual conditioned stimulus (CS) paired with food. Unlike normal rats, rats with neurotoxic lesions of the BLA failed to acquire Pavlovian second-order conditioning to an auditory stimulus paired with the first-order visual CS in the absence of food. In this experiment, we examined the role of BLA in the extinction of the previously acquired conditioned reinforcement value of a Pavlovian CS. Rats received first-order visual CS-food pairings prior to either BLA- or sham-lesions. Subsequent CS-alone extinction training reduced the ability of the visual CS to reinforce second-order conditioning of an auditory stimulus in the sham-lesioned rats, but not in the BLA-lesioned rats. Despite this persistence of the conditioned reinforcement value of the visual first-order CS in the BLA-lesioned rats, no effects of the lesions were observed on extinction of the explicit behavioural conditioned responses elicited by that CS.

  19. Infusions of AP5 into the basolateral amygdala impair the formation, but not the expression, of step-down inhibitory avoidance

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    Roesler R.

    2000-01-01

    Full Text Available We evaluated the effects of infusions of the NMDA receptor antagonist D,L-2-amino-5-phosphonopentanoic acid (AP5 into the basolateral nucleus of the amygdala (BLA on the formation and expression of memory for inhibitory avoidance. Adult male Wistar rats (215-300 g were implanted under thionembutal anesthesia (30 mg/kg, ip with 9.0-mm guide cannulae aimed 1.0 mm above the BLA. Bilateral infusions of AP5 (5.0 µg were given 10 min prior to training, immediately after training, or 10 min prior to testing in a step-down inhibitory avoidance task (0.3 mA footshock, 24-h interval between training and the retention test session. Both pre- and post-training infusions of AP5 blocked retention test performance. When given prior to the test, AP5 did not affect retention. AP5 did not affect training performance, and a control experiment showed that the impairing effects were not due to alterations in footshock sensitivity. The results suggest that NMDA receptor activation in the BLA is involved in the formation, but not the expression, of memory for inhibitory avoidance in rats. However, the results do not necessarily imply that the role of NMDA receptors in the BLA is to mediate long-term storage of fear-motivated memory within the amygdala.

  20. Incentive memory: evidence the basolateral amygdala encodes and the insular cortex retrieves outcome values to guide choice between goal-directed actions.

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    Parkes, Shauna L; Balleine, Bernard W

    2013-05-15

    Choice between goal-directed actions is determined by the relative value of their consequences. Such values are encoded during incentive learning and later retrieved to guide performance. Although the basolateral amygdala (BLA) and the gustatory region of insular cortex (IC) have been implicated in these processes, their relative contribution is still a matter of debate. Here we assessed whether these structures interact during incentive learning and retrieval to guide choice. In these experiments, rats were trained on two actions for distinct outcomes after which one of the two outcomes was devalued by specific satiety immediately before a choice extinction test. We first confirmed that, relative to appropriate controls, outcome devaluation recruited both the BLA and IC based on activation of the immediate early gene Arc; however, we found that infusion of the NMDAr antagonist ifenprodil into the BLA only abolished outcome devaluation when given before devaluation. In contrast, ifenprodil infusion into the IC was effective whether made before devaluation or test. We hypothesized that the BLA encodes and the IC retrieves incentive value for choice and, to test this, developed a novel sequential disconnection procedure. Blocking NMDAr activation unilaterally in the BLA before devaluation and then contralaterally in the IC before test abolished selective devaluation. In contrast, reversing the order of these infusions left devaluation intact. These results confirm that the BLA and IC form a circuit mediating the encoding and retrieval of outcome values, with the BLA encoding and the IC retrieving such values to guide choice.

  1. CaMKIIα knockdown decreases anxiety in the open field and low serotonin-induced upregulation of GluA1 in the basolateral amygdala.

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    Tran, Lee; Keele, N Bradley

    2016-04-15

    Hyperactivation of the amygdala is implicated in anxiety and mood disorders, but the precise underlying mechanisms are unclear. We previously reported that depletion of serotonin (5-hydroxytryptamine, 5-HT) in the basolateral nucleus of the amygdala (BLA) using the serotonergic neurotoxin 5,7-dihydroxytryptamine (5,7-DHT) potentiated learned fear and increased glutamate receptor (Glu) expression in BLA. Here we investigated the hypothesis that CaMKII facilitates anxiety-like behavior and increased Glu/AMPA receptor subunit A1 (GluA1) expression following depletion of 5-HT in the BLA. Infusion of 5,7-DHT into the BLA resulted in anxiety-like behavior in the open field test (OFT) and increased the phosphorylation of CaMKIIα (Thr-286) in the BLA. Knockdown of the CaMKIIα subunit using adeno-associated virus (AAV)-delivered shRNAi concomitantly attenuated anxiety-like behavior in the OFT and decreased GluA1 expression in the BLA. Our results suggest that the CaMKII signaling plays a key role in low 5-HT-induced anxiety and mood disturbances, potentially through regulation of GluA1 expression in the BLA.

  2. Estrogen receptor GPR30 exerts anxiolytic effects by maintaining the balance between GABAergic and glutamatergic transmission in the basolateral amygdala of ovariectomized mice after stress.

    Science.gov (United States)

    Tian, Zhen; Wang, Yu; Zhang, Nan; Guo, Yan-Yan; Feng, Bin; Liu, Shui-Bing; Zhao, Ming-Gao

    2013-10-01

    G-protein-coupled receptor 30 (GPR30)/G-protein-coupled estrogen receptor is a novel estrogen membrane receptor that localizes to the cell membrane and endoplasmic reticulum. GPR30 is widely distributed and has numerous physiological functions in the central nervous system. We found that GPR30 is highly expressed in the basolateral amygdala (BLA). Additionally, GPR30 expression in the amygdala of ovariectomized (OVX) mice significantly increased after acute stress and was accompanied by anxiety-like behaviors. These effects, however, were reversed by local infusion of the GPR30 agonist (G1) in the BLA. Protein assessments revealed that G1 attenuated the up-regulation of the GluR1 subunit of the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor and NR2A-containing N-methyl-d-aspartate receptors (NMDARs) in the BLA of OVX mice using an acute stress paradigm. In the same model, we found that the agonist also blocked the down-regulation of γ-aminobutyric acid A (GABAA) receptors and NR2B-containing NMDARs. Electrophysiological recording showed that the activation of GPR30 increased the inhibitory synaptic transmission in the BLA. Overall, our results indicate that estradiol reduces anxiety-like behaviors induced by acute stress at least partially through GPR30 signaling, maintaining the balance between GABAergic and glutamatergic transmission in the BLA of OVX-stressed mice.

  3. Post-training Activation of Rac1 in the Basolateral Amygdala Is Required for the Formation of both Short-term and Long-term Auditory Fear Memory

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    Qinqin eGao

    2015-11-01

    Full Text Available Rac1, a member of the Rho family of small GTPases, is crucial for morphological changes of the mature neuronal synapse including spine formation and activity-dependent spine enlargement, while its role in the formation of associated memories, such as conditioned fear memory, is not clear. Here we report that selective deletion of Rac1 in excitatory neurons, but not in parvalbumin inhibitory neurons, impaired short- and long-term memories (STM and LTM of fear conditioning. Conditional knockout of Rac1 before associative fear training in the basolateral amygdala (BLA, a key area for fear memory acquisition and storage, impaired fear memory. The expression of dominant-negative mutant of Rac1, or infusion of Rac1 inhibitor NSC23766 into BLA blocked both STM and LTM of fear conditioning. Furthermore, selective inhibition of Rac1 activation in BLA immediately following fear conditioning impaired STM, demonstrating that fear conditioning-induced Rac1 activation in BLA plays a critical role in the formation of both STM and LTM of conditioned fear.

  4. 大鼠杏仁体基底外侧核中小白蛋白反应阳性神经元受抑制性神经网络支配%PARVALBUMIN-IMMUNOREACTIVE INTERNEURONS ARE CONTROLLED BY AN INHIBITORY NEURONAL NETWORK IN BASOLATERAL NUCLEUS OF THE RAT AMYGDALA

    Institute of Scientific and Technical Information of China (English)

    李瑞锡; 彭裕文; 大谷 修; 西条 寿夫; 王劼; 丁忠良; 高璐; 沈馨亚

    2004-01-01

    As the elements of local neuronal circuits, parvalbumin (PV)-containing interneurons in the basolateral nucleus (BL) of the amygdala play an important role in the amygdaloid functions of emotion, learning and memory. In order to investigate how the PV-containing interneurons in the BL are controlled, the synapses established on PV- containing interneurons in the BL of the rat amygdala were examined under immunoelectron microscopy using the double labeling methods with anti-PV and anti-dopamine (DA) antibodies for a reference of dopaminergic axon terminals. The results show that the PV immunoreactive (IR) neurons formed the synapses mainly on the dendritic structures from shafts of the dendrites to median and small dendritic branches. 68% of the synapses on the PV-IR profiles were formed by unlabeled axon terminals, and 32 % of them were formed by DA- (21 % ) and PV- (11 % )IR axon terminals. Majority of the synapses on the PV-IR neurons formed by unlabeled axon terminals were symmetric type, and only a small a mount of them were asymmetric that were observed between the PV-IR spines and unlabeled axon terminals and in the serial synapses in which an unlabeled axon terminal symmetrically contacted to another unlabeled axon terminal that, in turn, synapsed asymmetrically to the PV-IR dendritic profiles. The synapses formed between the PV-IR profiles and DA- or PV-IR axon terminals were exclusively symmetric. The present results suggest that the PV-containing interneurons in the BL of the rat amygdala were controlled by an inhibitory network formed by the symmetric synapses around them, among which the DA system was included.%小白蛋白(PV)神经元作为杏仁核簇基底外侧核(BL)中局部神经环路成分,对杏仁核的情绪、学习和记忆过程等机能发挥重要作用.为探讨BL中PV中间神经元的突触形成状态,本研究用抗PV抗体标示PV神经元,以抗多巴胺(DA)抗体标示多巴胺能轴突及末梢作为传入纤维的标志,对

  5. Alcohol-Seeking Triggered by Discrete Pavlovian Cues is Invigorated by Alcohol Contexts and Mediated by Glutamate Signaling in the Basolateral Amygdala.

    Science.gov (United States)

    Sciascia, Joanna M; Reese, Rebecca M; Janak, Patricia H; Chaudhri, Nadia

    2015-11-01

    The environmental context in which a discrete Pavlovian conditioned stimulus (CS) is experienced can profoundly impact conditioned responding elicited by the CS. We hypothesized that alcohol-seeking behavior elicited by a discrete CS that predicted alcohol would be influenced by context and require glutamate signaling in the basolateral amygdala (BLA). Male, Long-Evans rats were allowed to drink 15% ethanol (v/v) until consumption stabilized. Next, rats received Pavlovian conditioning sessions in which a 10 s CS (15 trials/session) was paired with ethanol (0.2 ml/CS). Entries into a port where ethanol was delivered were measured. Pavlovian conditioning occurred in a specific context (alcohol context) and was alternated with sessions in a different context (non-alcohol context) where neither the CS nor ethanol was presented. At test, the CS was presented without ethanol in the alcohol context or the non-alcohol context, following a bilateral microinfusion (0.3 μl/hemisphere) of saline or the AMPA glutamate receptor antagonist NBQX (2,3-dioxo-6-nitro-1,2,3,4-tetrahydrobenzo[f]quinoxaline-7-sulfonamide disodium salt) in the BLA (0, 0.3, or 1.0 μg/0.3 μl). The effect of NBQX (0, 0.3 μg/0.3 μl) in the caudate putamen (CPu) on CS responding in the non-alcohol context was also tested. The discrete alcohol CS triggered more alcohol-seeking behavior in the alcohol context than the non-alcohol context. NBQX in the BLA reduced CS responding in both contexts but had no effect in the CPu. These data indicate that AMPA glutamate receptors in the BLA are critical for alcohol-seeking elicited by a discrete CS and that behavior triggered by the CS is strongly invigorated by an alcohol context.

  6. Cue-Induced Food Seeking After Punishment Is Associated With Increased Fos Expression in the Lateral Hypothalamus and Basolateral and Medial Amygdala.

    Science.gov (United States)

    Campbell, Erin J; Barker, David J; Nasser, Helen M; Kaganovsky, Konstantin; Dayas, Christopher V; Marchant, Nathan J

    2017-02-20

    In humans, relapse to unhealthy eating habits following dieting is a significant impediment to obesity treatment. Food-associated cues are one of the main triggers of relapse to unhealthy eating during self-imposed abstinence. Here we report a behavioral method examining cue-induced relapse to food seeking following punishment-induced suppression of food taking. We trained male rats to lever press for food pellets that were delivered after a 10-s conditional stimulus (CS) (appetitive). Following training, 25% of reinforced lever presses resulted in the presentation of a compound stimulus consisting of a novel CS (aversive) and the appetitive CS followed by a pellet and footshock. After punishment-imposed abstinence, we tested the rats in an extinction test where lever pressing resulted in the presentation of either the appetitive or aversive CS. We then compared activity of lateral hypothalamus (LH) and associated extrahypothalamic regions following this test. We also assessed Fos expression in LH orexin and GABA neurons. We found that cue-induced relapse of food seeking on test was higher in rats tested with the appetitive CS compared to the aversive CS. Relapse induced by the appetitive CS was associated with increased Fos expression in LH, caudal basolateral amygdala (BLA), and medial amygdala (MeA). This relapse was also associated with increased Fos expression in LH orexin and VGAT-expressing neurons. These data show that relapse to food seeking can be induced by food-associated cues after punishment-imposed abstinence, and this relapse is associated with increased activity in LH, caudal BLA, and MeA. (PsycINFO Database Record

  7. Lateral/Basolateral Amygdala Serotonin Type-2 Receptors Modulate Operant Self-administration of a Sweetened Ethanol Solution via Inhibition of Principal Neuron Activity

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    Brian eMccool

    2014-01-01

    Full Text Available The lateral/basolateral amygdala (BLA forms an integral part of the neural circuitry controlling innate anxiety and learned fear. More recently, BLA dependent modulation of self-administration behaviors suggests a much broader role in the regulation of reward evaluation. To test this, we employed a self-administration paradigm that procedurally segregates ‘seeking’ (exemplified as lever-press behaviors from consumption (drinking directed at a sweetened ethanol solution. Microinjection of the nonselective serotonin type-2 receptor agonist, alpha-methyl-5-hydroxytryptamine (-m5HT into the BLA reduced lever pressing behaviors in a dose-dependent fashion. This was associated with a significant reduction in the number of response-bouts expressed during non-reinforced sessions without altering the size of a bout or the rate of responding. Conversely, intra-BLA -m5HT only modestly effected consumption-related behaviors; the highest dose reduced the total time spent consuming a sweetened ethanol solution but did not inhibit the total number of licks, number of lick bouts, or amount of solution consumed during a session. In vitro neurophysiological characterization of BLA synaptic responses showed that -m5HT significantly reduced extracellular field potentials. This was blocked by the 5-HT2A/C antagonist ketanserin suggesting that 5-HT2-like receptors mediate the behavioral effect of -m5HT. During whole-cell patch current-clamp recordings, we subsequently found that -m5HT increased action potential threshold and hyperpolarized the resting membrane potential of BLA pyramidal neurons. Together, our findings show that the activation of BLA 5-HT2A/C receptors inhibits behaviors related to reward-seeking by suppressing BLA principal neuron activity. These data are consistent with the hypothesis that the BLA modulates reward-related behaviors and provides specific insight into BLA contributions during operant self-administration of a

  8. Serotonin-2C receptors in the basolateral nucleus of the amygdala mediate the anxiogenic effect of acute imipramine and fluoxetine administration.

    Science.gov (United States)

    Vicente, Maria Adrielle; Zangrossi, Helio

    2012-04-01

    A growing body of evidence indicates that facilitation of serotonin-2C receptor (5-HT2CR)-mediated neurotransmission in the basolateral nucleus of the amygdala (BLA) is involved in anxiety generation. We investigated here whether BLA 5-HT2CRs exert a differential role in the regulation of defensive behaviours related to generalized anxiety (inhibitory avoidance) and panic (escape) disorders. We also evaluated whether activation of BLA 5-HT2CRs accounts for the anxiogenic effect caused by acute systemic administration of the antidepressants imipramine and fluoxetine. Male Wistar rats were tested in the elevated T-maze after intra-BLA injection of the endogenous agonist 5-HT, the 5-HT2CR agonist MK-212 or the 5-HT2CR antagonist SB-242084. This test allows the measurement of inhibitory avoidance acquisition and escape expression. We also investigated whether intra-BLA administration of SB-242084 interferes with the acute anxiogenic effect caused by imipramine and fluoxetine in the Vogel conflict test, and imipramine in the elevated T-maze. While intra-BLA administration of 5-HT and MK-212 facilitated inhibitory avoidance acquisition, suggesting an anxiogenic effect, SB-242084 had the opposite effect. None of these drugs affected escape performance. Intra-BLA injection of a sub-effective dose of SB-242084 fully blocked the anxiogenic effect caused either by the local microinjection of 5-HT or the systemic administration of imipramine and fluoxetine. Our findings indicate that 5-HT2CRs in BLA are selectively involved in the regulation of defensive behaviours associated with generalized anxiety, but not panic. The results also provide the first direct evidence that activation of BLA 5-HT2CRs accounts for the short-term aversive effect of antidepressants.

  9. Behavioral and neurophysiological evidence that lateral paracapsular GABAergic synapses in the basolateral amygdala contribute to the acquisition and extinction of fear learning.

    Science.gov (United States)

    Skelly, M J; Chappell, A M; Ariwodola, O J; Weiner, J L

    2016-01-01

    The lateral/basolateral amygdala (BLA) is crucial to the acquisition and extinction of Pavlovian fear conditioning, and synaptic plasticity in this region is considered to be a neural correlate of learned fear. We recently reported that activation of BLA β3-adrenoreceptors (β3-ARs) selectively enhances lateral paracapsular (LPC) feed-forward GABAergic inhibition onto BLA pyramidal neurons, and that intra-BLA infusion of a β3-AR agonist reduces measures of unconditioned anxiety-like behavior. Here, we utilized a combination of behavioral and electrophysiological approaches to characterize the role of BLA LPCs in the acquisition of fear and extinction learning in adult male Long-Evans rats. We report that intra-BLA microinjection of β3-AR agonists (BRL37344 or SR58611A, 1μg/0.5μL/side) prior to training fear conditioning or extinction blocks the expression of these behaviors 24h later. Furthermore,ex vivo low-frequency stimulation of the external capsule (LFS; 1Hz, 15min), which engages LPC synapses, induces LTP of BLA fEPSPs, while application of a β3-AR agonist (SR58611A, 5μM) induces LTD of fEPSPs when combined with LFS. Interestingly, fEPSP LTP is not observed in recordings from fear conditioned animals, suggesting that fear learning may engage the same mechanisms that induce synaptic plasticity at this input. In support of this, we find that LFS produces LTD of inhibitory postsynaptic currents (iLTD) at LPC GABAergic synapses, and that this effect is also absent following fear conditioning. Taken together, these data provide preliminary evidence that modulation of LPC GABAergic synapses can influence the acquisition and extinction of fear learning and related synaptic plasticity in the BLA.

  10. The inactivation of the basolateral nucleus of the rat amygdala has an anxiolytic effect in the elevated T-maze and light/dark transition tests

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    Bueno C.H.

    2005-01-01

    Full Text Available Pharmacological evidence indicates that the basolateral nucleus of the amygdala (BLA is involved in the mediation of inhibitory avoidance but not of escape behavior in the elevated T-maze test. These defensive responses have been associated with generalized anxiety disorder (GAD and panic disorder, respectively. In the present study, we determined whether the BLA plays a differential role in the control of inhibitory avoidance and escape responses in the elevated T-maze. Male Wistar rats (250-280 g, N = 9-10 in each treatment group were pre-exposed to one of the open arms of the maze for 30 min and 24 h later tested in the model after inactivation of the BLA by a local injection of the GABA A receptor agonist muscimol (8 nmol in 0.2 µL. It has been shown that a prior forced exposure to one of the open arms of the maze, by shortening latencies to withdrawal from the open arm during the test, improves the escape task as a behavioral index of panic. The effects of muscimol in the elevated T-maze were compared to those caused by this GABA agonist in the avoidance reaction generated in the light/dark transition test. This defensive behavior has also been associated with GAD. In the elevated T-maze, intra-BLA injection of muscimol impaired inhibitory avoidance (control: 187.70 ± 14.90 s, muscimol: 37.10 ± 2.63 s, indicating an anxiolytic effect, without interfering with escape performance. The drug also showed an anxiolytic effect in the light/dark transition test as indicated by the increase in the time spent in the lighted compartment (control: 23.50 ± 2.45 s, muscimol: 47.30 ± 4.48 s. The present findings point to involvement of the BLA in the modulation of defensive responses that have been associated with GAD.

  11. Anxiolytic effects of kindling role of anatomical location of the kindling electrode in response to kindling of the right basolateral amygdala.

    Science.gov (United States)

    Adamec, Robert; Blundell, Jacqueline; Burton, Paul

    2004-10-22

    Study of effects of kindling on affect has been complicated by the fact that anxiogenic, anxiolytic or no effects may be observed following kindling of the amygdala. Factors affecting behavioral outcome include strain of rat, hemisphere kindled, amygdala nucleus kindled and location of the kindling electrodes within particular AP planes of a given nucleus. Previous work has suggested that kindling of the right basolateral amygdala (BLA) is predominantly anxiogenic. This conclusion was based on kindling of anterior or posterior parts of the BLA. The present study sought to clarify this conclusion by examining behavioral effects of right BLA kindling in a mid-range of AP planes not yet studied. A variety of measures of rodent anxiety-like behavior were examined, including behavior in the hole board, elevated plus maze, light/dark box, social interaction test and unconditioned acoustic startle. Anhedonic effects of kindling were assessed by a sucrose preference test with controls for fluid consumption and taste sensitivities. All effects were assessed shortly after kindling (1-2 days) and at a longer time interval (7-8 days). Kindling to four stage 5 seizures in the mid-right BLA altered behavior at all time points after kindling in all tests except the hole board and light/dark box tests. The effect of kindling was anxiolytic like in the plus maze, social interaction and startle tests. Kindling in mid-BLA also increased sucrose consumption. Effects on sucrose consumption are consistent with previous studies showing no depressive-like effects of amygdala kindling in rodents. It is hypothesized that the focal nature of the behavioral consequences of amygdala kindling are best understood in the context of the circuitry in which the cells stimulated are imbedded and the impact of kindling on functioning of those circuits.

  12. Vectorial transport of nucleoside analogs from the apical to the basolateral membrane in double-transfected cells expressing the human concentrative nucleoside transporter hCNT3 and the export pump ABCC4.

    Science.gov (United States)

    Rius, Maria; Keller, Daniela; Brom, Manuela; Hummel-Eisenbeiss, Johanna; Lyko, Frank; Keppler, Dietrich

    2010-07-01

    The identification of the transport proteins responsible for the uptake and the efflux of nucleosides and their metabolites enables the characterization of their vectorial transport and a better understanding of their absorption, distribution, and elimination. Human concentrative nucleoside transporters (hCNTs/SLC28A) are known to mediate the transport of natural nucleosides and some nucleoside analogs into cells in a sodium-dependent and unidirectional manner. On the other hand, several human multidrug resistance proteins [human ATP-binding cassette transporter, subfamily C (ABCC)] cause resistance against nucleoside analogs and mediate transport of phosphorylated nucleoside derivatives out of the cells in an ATP-dependent manner. For the integrated analysis of uptake and efflux of these compounds, we established a double-transfected Madin-Darby canine kidney (MDCK) II cell line stably expressing the human uptake transporter hCNT3 in the apical membrane and the human efflux pump ABCC4 in the basolateral membrane. The direction of transport was from the apical to the basolateral compartment, which is in line with the unidirectional transport and the localization of both recombinant proteins in the MDCKII cells. Recombinant hCNT3 mediated the transport of several known nucleoside substrates, and we identified 5-azacytidine as a new substrate for hCNT3. It is of interest that coexpression of both transporters was confirmed in pancreatic adenocarcinomas, which represent an important clinical indication for the therapeutic use of nucleoside analogs. Thus, our results establish a novel cell system for studies on the vectorial transport of nucleosides and their analogs from the apical to the basolateral compartment. The results contribute to a better understanding of the cellular transport characteristics of nucleoside drugs.

  13. Moderate alcohol exposure during the rat equivalent to the third trimester of human pregnancy alters dopamine regulation of GABAA receptor-mediated transmission in the basolateral amygdala

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    Marvin Rafael Diaz

    2014-05-01

    Full Text Available Fetal ethanol (EtOH exposure leads to a range of neurobehavioral alterations, including deficits in emotional processing. The basolateral amygdala (BLA plays a critical role in modulating emotional processing, in part, via dopamine (DA regulation of GABA transmission. This BLA modulatory system is acquired during the first two weeks of postnatal life in rodents (equivalent to the 3rd trimester of human pregnancy and we hypothesized that it could be altered by EtOH exposure during this period. We found that exposure of rats to moderate levels of EtOH vapor during the 3rd trimester-equivalent (postnatal days (P 2-12 alters DA modulation of GABAergic transmission in BLA pyramidal neurons during periadolescence. Specifically, D1R-mediated potentiation of spontaneous inhibitory postsynaptic currents (IPSCs was significantly attenuated in EtOH-exposed animals. However, this was associated with a compensatory decrease in D3R-mediated suppression of miniature IPSCs. Western blot analysis revealed that these effects were not a result of altered D1R or D3R levels. BLA samples from EtOH-exposed animals also had significantly lower levels of the DA precursor (L-3,4-dihydroxyphenylalanine but DA levels were not affected. This is likely a consequence of reduced catabolism of DA, as indicated by reduced levels of 3,4-dihydroxyphenylacetic acid and homovanillic acid in the BLA samples. Anxiety-like behavior was not altered in EtOH-exposed animals. This is the first study to demonstrate that the modulatory actions of DA in the BLA are altered by developmental EtOH exposure. Although compensatory adaptations were engaged in our moderate EtOH exposure paradigm, it is possible that these are not able to restore homeostasis and correct anxiety-like behaviors under conditions of heavier EtOH exposure. Therefore, future studies should investigate the potential role of alterations in the modulatory actions of DA in the pathophysiology of fetal alcohol spectrum

  14. Presynaptic facilitation of glutamate release in the basolateral amygdala: a mechanism for the anxiogenic and seizurogenic function of GluK1 receptors.

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    Aroniadou-Anderjaska, V; Pidoplichko, V I; Figueiredo, T H; Almeida-Suhett, C P; Prager, E M; Braga, M F M

    2012-09-27

    Kainate receptors containing the GluK1 subunit (GluK1Rs; previously known as GluR5 kainate receptors) are concentrated in certain brain regions, where they play a prominent role in the regulation of neuronal excitability, by modulating GABAergic and/or glutamatergic synaptic transmission. In the basolateral nucleus of the amygdala (BLA), which plays a central role in anxiety as well as in seizure generation, GluK1Rs modulate GABAergic inhibition via postsynaptic and presynaptic mechanisms. However, the role of these receptors in the regulation of glutamate release, and the net effect of their activation on the excitability of the BLA network are not well understood. Here, we show that in amygdala slices from 35- to 50-day-old rats, the GluK1 agonist (RS)-2-amino-3-(3-hydroxy-5-tert-butylisoxazol-4-yl) propanoic acid (ATPA) (300 nM) increased the frequency of spontaneous excitatory postsynaptic currents (sEPSCs) and miniature EPSCs (mEPSCs) recorded from BLA principal neurons, and decreased the rate of failures of evoked EPSCs. The GluK1 antagonist (S)-1-(2-amino-2-carboxyethyl)-3-(2-carboxybenzyl) pyrimidine-2,4-dione (UBP302) (25 or 30 μM) decreased the frequency of mEPSCs, reduced evoked field potentials, and increased the "paired-pulse ratio" of the field potential amplitudes. Taken together, these results suggest that GluK1Rs in the rat BLA are present on presynaptic terminals of principal neurons, where they mediate facilitation of glutamate release. In vivo bilateral microinjections of ATPA (250 pmol) into the rat BLA increased anxiety-like behavior in the open field test, while 2 nmol ATPA induced seizures. Similar intra-BLA injections of UBP302 (20 nmol) had anxiolytic effects in the open field and the acoustic startle response tests, without affecting pre-pulse inhibition. These results suggest that although GluK1Rs in the rat BLA facilitate both GABA and glutamate release, the facilitation of glutamate release prevails, and these receptors can have an

  15. 5-HT2C receptors in the basolateral amygdala and dorsal striatum are a novel target for the anxiolytic and antidepressant effects of exercise.

    Directory of Open Access Journals (Sweden)

    Benjamin N Greenwood

    Full Text Available Physical activity reduces the incidence and severity of psychiatric disorders such as anxiety and depression. Similarly, voluntary wheel running produces anxiolytic- and antidepressant-like effects in rodent models. The specific neurobiological mechanisms underlying the beneficial properties of exercise, however, remain unclear. One relevant pharmacological target in the treatment of psychiatric disorders is the 5-HT(2C receptor (5-HT(2CR. Consistent with data demonstrating the anxiogenic consequences of 5-HT(2CR activation in humans and rodents, we have previously reported that site-specific administration of the selective 5-HT(2CR agonist CP-809101 in the lateral/basolateral amygdala (BLA increases shock-elicited fear while administration of CP-809101 in the dorsal striatum (DS interferes with shuttle box escape learning. These findings suggest that activation of 5-HT(2CR in discrete brain regions contributes to specific anxiety- and depression-like behaviors and may indicate potential brain sites involved in the anxiolytic and antidepressant effects of exercise. The current studies tested the hypothesis that voluntary wheel running reduces the behavioral consequences of 5-HT(2CR activation in the BLA and DS, specifically enhanced shock-elicited fear and interference with shuttle box escape learning. After 6 weeks of voluntary wheel running or sedentary conditions, the selective 5-HT(2CR agonist CP-809101 was microinjected into either the BLA or the DS of adult Fischer 344 rats, and shock-elicited fear and shuttle box escape learning was assessed. Additionally, in-situ hybridization was used to determine if 6 weeks of voluntary exercise changed levels of 5-HT(2CR mRNA. We found that voluntary wheel running reduced the behavioral effects of CP-809101 and reduced levels of 5-HT(2CR mRNA in both the BLA and the DS. The current data indicate that expression of 5-HT(2CR mRNA in discrete brain sites is sensitive to physical activity status of the

  16. Carney Complex

    Science.gov (United States)

    ... Types of Cancer > Carney Complex Request Permissions Carney Complex Approved by the Cancer.Net Editorial Board , 11/2015 What is Carney complex? Carney complex is a hereditary condition associated with: ...

  17. Complex Beauty

    OpenAIRE

    Franceschet, Massimo

    2014-01-01

    Complex systems and their underlying convoluted networks are ubiquitous, all we need is an eye for them. They pose problems of organized complexity which cannot be approached with a reductionist method. Complexity science and its emergent sister network science both come to grips with the inherent complexity of complex systems with an holistic strategy. The relevance of complexity, however, transcends the sciences. Complex systems and networks are the focal point of a philosophical, cultural ...

  18. Common channels for water and protons at apical and basolateral cell membranes of frog skin and urinary bladder epithelia. Effects of oxytocin, heavy metals, and inhibitors of H(+)-adenosine triphosphatase

    Energy Technology Data Exchange (ETDEWEB)

    Harvey, B.; Lacoste, I.; Ehrenfeld, J. (Commissariat a l' Energie Atomique, Villefranche-sur-mer (France))

    1991-04-01

    We have compared the response of proton and water transport to oxytocin treatment in isolated frog skin and urinary bladder epithelia to provide further insights into the nature of water flow and H+ flux across individual apical and basolateral cell membranes. In isolated spontaneous sodium-transporting frog skin epithelia, lowering the pH of the apical solution from 7.4 to 6.4, 5.5, or 4.5 produced a fall in pHi in principal cells which was completely blocked by amiloride, indicating that apical Na+ channels are permeable to protons. When sodium transport was blocked by amiloride, the H+ permeability of the apical membranes of principal cells was negligible but increased dramatically after treatment with antidiuretic hormone (ADH). In the latter condition, lowering the pH of the apical solution caused a voltage-dependent intracellular acidification, accompanied by membrane depolarization, and an increase in membrane conductance and transepithelial current. These effects were inhibited by adding Hg2+ (100 microM) or dicyclohexylcarbodiimide (DCCD, 10(-5) M) to the apical bath. Net titratable H+ flux across frog skin was increased from 30 +/- 8 to 115 +/- 18 neq.h-1.cm-2 (n = 8) after oxytocin treatment (at apical pH 5.5 and serosal pH 7.4) and was completely inhibited by DCCD (10(-5) M). The basolateral membranes of the principal cells in frog skin epithelium were found to be spontaneously permeable to H+ and passive electrogenic H+ transport across this membrane was not affected by oxytocin. Lowering the pH of the basolateral bathing solution (pHb) produced an intracellular acidification and membrane depolarization (and an increase in conductance when the normal dominant K+ conductance of this membrane was abolished by Ba2+ 1 mM). These effects of low pHb were blocked by micromolar concentrations of heavy metals (Zn2+, Ni2+, Co2+, Cd2+, and Hg2+).

  19. High-mobility group box 1 inhibits HCO3- absorption in the medullary thick ascending limb through RAGE-Rho-ROCK-mediated inhibition of basolateral Na+/H+ exchange.

    Science.gov (United States)

    Watts, Bruns A; George, Thampi; Badalamenti, Andrew; Good, David W

    2016-09-01

    High-mobility group box 1 (HMGB1) is a nuclear protein released extracellularly in response to infection or injury, where it activates immune responses and contributes to the pathogenesis of kidney dysfunction in sepsis and sterile inflammatory disorders. Recently, we demonstrated that HMGB1 inhibits HCO3 (-) absorption in perfused rat medullary thick ascending limbs (MTAL) through a basolateral receptor for advanced glycation end products (RAGE)-dependent pathway that is additive to Toll-like receptor 4 (TLR4)-ERK-mediated inhibition by LPS (Good DW, George T, Watts BA III. Am J Physiol Renal Physiol 309: F720-F730, 2015). Here, we examined signaling and transport mechanisms that mediate inhibition by HMGB1. Inhibition of HCO3 (-) absorption by HMGB1 was eliminated by the Rho-associated kinase (ROCK) inhibitor Y27632 and by a specific inhibitor of Rho, the major upstream activator of ROCK. HMGB1 increased RhoA and ROCK1 activity. HMGB1-induced ROCK1 activation was eliminated by the RAGE antagonist FPS-ZM1 and by inhibition of Rho. The Rho and ROCK inhibitors had no effect on inhibition of HCO3 (-) absorption by bath LPS. Inhibition of HCO3 (-) absorption by HMGB1 was eliminated by bath amiloride, 0 Na(+) bath, and the F-actin stabilizer jasplakinolide, three conditions that selectively prevent inhibition of MTAL HCO3 (-) absorption mediated through NHE1. HMGB1 decreased basolateral Na(+)/H(+) exchange activity through activation of ROCK. We conclude that HMGB1 inhibits HCO3 (-) absorption in the MTAL through a RAGE-RhoA-ROCK1 signaling pathway coupled to inhibition of NHE1. The HMGB1-RAGE-RhoA-ROCK1 pathway thus represents a potential target to attenuate MTAL dysfunction during sepsis and other inflammatory disorders. HMGB1 and LPS inhibit HCO3 (-) absorption through different receptor signaling and transport mechanisms, which enables these pathogenic mediators to act directly and independently to impair MTAL function.

  20. Amygdala upregulation of NCAM polysialylation induced by auditory fear conditioning is not required for memory formation, but plays a role in fear extinction.

    Science.gov (United States)

    Markram, Kamila; Lopez Fernandez, Miguel Angel; Abrous, Djoher Nora; Sandi, Carmen

    2007-05-01

    There is much interest to understand the mechanisms leading to the establishment, maintenance, and extinction of fear memories. The amygdala has been critically involved in the processing of fear memories and a number of molecular changes have been implicated in this brain region in relation to fear learning. Although neural cell adhesion molecules (NCAMs) have been hypothesized to play a role, information available about their contribution to fear memories is scarce. We investigate here whether polysialylated NCAM (PSA-NCAM) contributes to auditory fear conditioning in the amygdala. First, PSA-NCAM expression was evaluated in different amygdala nuclei after auditory fear conditioning at two different shock intensities. Results showed that PSA-NCAM expression was increased 24 h post-training only in animals subjected to the highest shock intensity (1mA). Second, PSA-NCAM was cleaved in the basolateral amygdaloid complex through micro-infusions of the enzyme endoneuraminidase N, and the consequences of such treatment were investigated on the acquisition, consolidation, remote memory expression, and extinction of conditioned fear memories. Intra-amygdaloid cleavage of PSA-NCAM did not affect acquisition, consolidation or expression of remote fear memories. However, intra-amygdaloid PSA-NCAM cleavage enhanced fear extinction processes. These results suggest that upregulation of PSA-NCAM is a correlate of fear conditioning that is not necessary for the establishment of fear memory in the amygdala, but participates in mechanisms precluding fear extinction. These findings point out PSA-NCAM as a potential target for the treatment of psychopathologies that involve impairment in fear extinction.

  1. Differential efferent projections of the anterior, posteroventral and posterodorsal subdivisions of the medial amygdala in mice

    Directory of Open Access Journals (Sweden)

    Cecília ePardo-Bellver

    2012-08-01

    Full Text Available The medial amygdaloid nucleus (Me is a key structure in the control of sociosexual behaviour in mice. It receives direct projections from the main and accessory olfactory bulbs, as well as an important hormonal input. To better understand its behavioural role, in this work we investigate the structures receiving information from the Me, by analysing the efferent projections from its anterior (MeA, posterodorsal (MePD and posteroventral (MePV subdivisions, using anterograde neuronal tracing with biotinylated and tetrametylrhodamine-conjugated dextranamines.The Me is strongly interconnected with the rest of the chemosensory amygdala, but shows only moderate projections to the central nucleus and light projections to the associative nuclei of the basolateral amygdaloid complex. In addition, the MeA originates a strong feedback projection to the deep mitral cell layer of the accessory olfactory bulb, whereas the MePV projects to its granule cell layer. The medial amygdaloid nucleus (especially the MeA has also moderate projections to different olfactory structures, including the piriform cortex. The densest outputs of the Me target the bed nucleus of the stria terminalis (BST and the hypothalamus. The MeA and MePV project to key structures of the circuit involved in the defensive response against predators (medial posterointermediate BST, anterior hypothalamic area, dorsomedial aspect of the ventromedial hypothalamic nucleus, although less dense projections also innervate reproductive-related nuclei. In contrast, the MePD projects mainly to structures that control reproductive behaviours (medial posteromedial BST, medial preoptic nucleus, and ventrolateral aspect of the ventromedial hypothalamic nucleus, although less dense projections to defensive-related nuclei also exist. These results confirm and extend previous results in other rodents and suggest that the medial amygdala is anatomically and functionally compartmentalized.

  2. Cholinergic cells in the nucleus basalis of mice express the N-methyl-D-aspartate-receptor subunit NR2C and its replacement by the NR2B subunit enhances frontal and amygdaloid acetylcholine levels

    NARCIS (Netherlands)

    De Souza Silva, M. A.; Dolga, Amalia; Pieri, I.; Marchetti, L.; Eisel, U. L. M.; Huston, J. P.; Dere, E.

    2006-01-01

    It is known that glutamatergic and cholinergic systems interact functionally at the level of the cholinergic basal forebrain. The N-methyl-D-aspartate receptor (NMDA-R) is a multiprotein complex composed of NR1, NR2 and/or NR3 subunits. The subunit composition of NMDA-R of cholinergic cells in the n

  3. Dynamin-like protein 1 at the Golgi complex: A novel component of the sorting/targeting machinery en route to the plasma membrane

    Energy Technology Data Exchange (ETDEWEB)

    Bonekamp, Nina A. [Centre for Cell Biology and Department of Biology, University of Aveiro, Campus Universitario de Santiago, 3810-193 Aveiro (Portugal); Vormund, Kerstin; Jacob, Ralf [Department of Cell Biology and Cell Pathology, University of Marburg, Robert-Koch-Str. 6, 35037 Marburg (Germany); Schrader, Michael, E-mail: mschrader@ua.pt [Centre for Cell Biology and Department of Biology, University of Aveiro, Campus Universitario de Santiago, 3810-193 Aveiro (Portugal)

    2010-12-10

    The final step in the liberation of secretory vesicles from the trans-Golgi network (TGN) involves the mechanical action of the large GTPase dynamin as well as conserved dynamin-independent fission mechanisms, e.g. mediated by Brefeldin A-dependent ADP-ribosylated substrate (BARS). Another member of the dynamin family is the mammalian dynamin-like protein 1 (DLP1/Drp1) that is known to constrict and tubulate membranes, and to divide mitochondria and peroxisomes. Here, we examined a potential role for DLP1 at the Golgi complex. DLP1 localized to the Golgi complex in some but not all cell lines tested, thus explaining controversial reports on its cellular distribution. After silencing of DLP1, an accumulation of the apical reporter protein YFP-GL-GPI, but not the basolateral reporter VSVG-SP-GFP at the Golgi complex was observed. A reduction in the transport of YFP-GL-GPI to the plasma membrane was confirmed by surface immunoprecipitation and TGN-exit assays. In contrast, YFP-GL-GPI trafficking was not disturbed in cells silenced for BARS, which is involved in basolateral sorting and trafficking of VSVG-SP-GFP in COS-7 cells. Our data indicate a new role for DLP1 at the Golgi complex and thus a role for DLP1 as a novel component of the apical sorting machinery at the TGN is discussed.

  4. Dynamin-like protein 1 at the Golgi complex: a novel component of the sorting/targeting machinery en route to the plasma membrane.

    Science.gov (United States)

    Bonekamp, Nina A; Vormund, Kerstin; Jacob, Ralf; Schrader, Michael

    2010-12-10

    The final step in the liberation of secretory vesicles from the trans-Golgi network (TGN) involves the mechanical action of the large GTPase dynamin as well as conserved dynamin-independent fission mechanisms, e.g. mediated by Brefeldin A-dependent ADP-ribosylated substrate (BARS). Another member of the dynamin family is the mammalian dynamin-like protein 1 (DLP1/Drp1) that is known to constrict and tubulate membranes, and to divide mitochondria and peroxisomes. Here, we examined a potential role for DLP1 at the Golgi complex. DLP1 localized to the Golgi complex in some but not all cell lines tested, thus explaining controversial reports on its cellular distribution. After silencing of DLP1, an accumulation of the apical reporter protein YFP-GL-GPI, but not the basolateral reporter VSVG-SP-GFP at the Golgi complex was observed. A reduction in the transport of YFP-GL-GPI to the plasma membrane was confirmed by surface immunoprecipitation and TGN-exit assays. In contrast, YFP-GL-GPI trafficking was not disturbed in cells silenced for BARS, which is involved in basolateral sorting and trafficking of VSVG-SP-GFP in COS-7 cells. Our data indicate a new role for DLP1 at the Golgi complex and thus a role for DLP1 as a novel component of the apical sorting machinery at the TGN is discussed.

  5. Bucolic Complexes

    CERN Document Server

    Brešar, Bostjan; Chepoi, Victor; Gologranc, Tanja; Osajda, Damian

    2012-01-01

    In this article, we introduce and investigate bucolic complexes, a common generalization of systolic complexes and of CAT(0) cubical complexes. This class of complexes is closed under Cartesian products and amalgamations over some convex subcomplexes. We study various approaches to bucolic complexes: from graph-theoretic and topological viewpoints, as well as from the point of view of geometric group theory. Bucolic complexes can be defined as locally-finite simply connected prism complexes satisfying some local combinatorial conditions. We show that bucolic complexes are contractible, and satisfy some nonpositive-curvature-like properties. In particular, we prove a version of the Cartan-Hadamard theorem, the fixed point theorem for finite group actions, and establish some results on groups acting geometrically on such complexes. We also characterize the 1-skeletons (which we call bucolic graphs) and the 2-skeletons of bucolic complexes. In particular, we prove that bucolic graphs are precisely retracts of Ca...

  6. Complexity Plots

    KAUST Repository

    Thiyagalingam, Jeyarajan

    2013-06-01

    In this paper, we present a novel visualization technique for assisting the observation and analysis of algorithmic complexity. In comparison with conventional line graphs, this new technique is not sensitive to the units of measurement, allowing multivariate data series of different physical qualities (e.g., time, space and energy) to be juxtaposed together conveniently and consistently. It supports multivariate visualization as well as uncertainty visualization. It enables users to focus on algorithm categorization by complexity classes, while reducing visual impact caused by constants and algorithmic components that are insignificant to complexity analysis. It provides an effective means for observing the algorithmic complexity of programs with a mixture of algorithms and black-box software through visualization. Through two case studies, we demonstrate the effectiveness of complexity plots in complexity analysis in research, education and application. © 2013 The Author(s) Computer Graphics Forum © 2013 The Eurographics Association and Blackwell Publishing Ltd.

  7. Anxiolytic and anxiogenic effects of kindling--role of baseline anxiety and anatomical location of the kindling electrode in response to kindling of the right and left basolateral amygdala.

    Science.gov (United States)

    Adamec, Robert; Shallow, Tanya; Burton, Paul

    2005-04-15

    Effects of kindling of right and left basolateral amygdala (BLA) on plus maze anxiety was studied. Using a validated retest paradigm, it was possible to retest rats in the plus maze without increasing anxiety on retest. This permitted determining prekindling baseline levels of plus maze anxiety. Right BLA kindling of high baseline anxiety rats was anxiolytic one week after kindling. Right BLA kindling of low baseline anxiety rats was anxiogenic. In addition, left BLA kindling was either anxiogenic or without effect on plus maze anxiety, depending on baseline anxiety. Effects in left BLA differ from previous work showing anxiolytic effects of left BLA kindling. The discrepancy could be explained in part by prekindling baseline anxiety. These findings require modification of the previous conclusion that left hemisphere (left BLA) kindling is anxiolytic and right BLA kindling is anxiogenic in the plus maze. Rather the hemisphere difference may be due to an interaction between baseline anxiety level and kindling. If true, anxious disposition in rodents may interact with amygdala kindling to change amygdala function differently. Kindling and baseline anxiety effects on other behaviors (such as risk assessment and resistance to capture) are also described. Present data in the light of past studies suggest both premorbid anxiety state and location of the kindling electrode contribute to the effects of kindling on behavior.

  8. CB1 Cannabinoid Agonist (WIN55,212-2) Within the Basolateral Amygdala Induced Sensitization to Morphine and Increased the Level of μ-Opioid Receptor and c-fos in the Nucleus Accumbens.

    Science.gov (United States)

    Molaei, Marzieh; Fatahi, Zahra; Zaringhalam, Jalal; Haghparast, Abbas

    2016-04-01

    The basolateral amygdala (BLA) is rich of CB1 cannabinoid receptors (CB1R) and has reciprocal connections with the nucleus accumbens (NAc) which is involved in opioid sensitization. In this study, effects of intra-BLA administration of CB1R agonist on sensitization to antinociceptive effect of morphine and changes in the levels of μ-opioid receptor (MOR), p-CREB, and c-fos in the NAc were investigated. Animals received intra-BLA microinjection of CB1R agonist (WIN55,212-2) once daily for 3 days consecutively (sensitization period). After 5 days free of drug, tail-flick test was performed before and after the administration of an ineffective dose of morphine. Afterward, the levels of MOR, p-CREB, and c-fos proteins were measured in the NAc by Western blot analysis. The results indicated that intra-BLA injection of WIN55,212-2 during sensitization period resulted in the induction of antinociceptive responses by ineffective dose of morphine and caused a significant increase in the MOR and c-fos levels but not p-CREB/CREB ratio in the NAc. These finding revealed that CB1 receptor agonist in the BLA induces development of morphine sensitization and increases expression of MOR in the NAc. It seems that c-fos is one of the important factors involved in the induction of sensitization to antinociceptive effect of morphine.

  9. Engaging complexity

    Directory of Open Access Journals (Sweden)

    Gys M. Loubser

    2014-01-01

    Full Text Available In this article, I discuss studies in complexity and its epistemological implications for systematic and practical theology. I argue that engagement with complexity does not necessarily assurea non-reductionist approach. However, if complexity is engaged transversally, it becomes possible to transcend reductionist approaches. Moreover, systematic and practical the ologians can draw on complexity in developing new ways of understanding and, therefore, new ways of describing the focus, epistemic scope and heuristic structures of systematic and practical theology. Firstly, Edgar Morin draws a distinction between restricted and general complexity based on the epistemology drawn upon in studies in complexity. Moving away from foundationalist approaches to epistemology, Morin argues for a paradigm of systems. Secondly,I discuss Kees van Kooten Niekerk�s distinction between epistemology, methodology andontology in studies in complexity and offer an example of a theological argument that drawson complexity. Thirdly, I argue for the importance of transversality in engaging complexity by drawing on the work of Wentzel van Huyssteen and Paul Cilliers. In conclusion, I argue that theologians have to be conscious of the epistemic foundations of each study in complexity, and these studies illuminate the heart of Reformed theology.Intradisciplinary and/or interdisciplinary implications: Therefore, this article has both intradisciplinary and interdisciplinary implications. When theologians engage studies incomplexity, the epistemological roots of these studies need to be considered seeing thatresearchers in complexity draw on different epistemologies. Drawing on transversality wouldenhance such considerations. Furthermore, Edgar Morin�s and Paul Cilliers� approach tocomplexity will inform practical and theoretical considerations in church polity and unity.

  10. Simplifying complexity

    NARCIS (Netherlands)

    Leemput, van de I.A.

    2016-01-01

    In this thesis I use mathematical models to explore the properties of complex systems ranging from microbial nitrogen pathways and coral reefs to the human state of mind. All are examples of complex systems, defined as systems composed of a number of interconnected parts, where the systemic behavior

  11. Complex odontoma.

    Science.gov (United States)

    Preetha, A; Balikai, Bharati S; Sujatha, D; Pai, Anuradha; Ganapathy, K S

    2010-01-01

    Odontomas are hamartomatous lesions or malformations composed of mature enamel, dentin, and pulp. They may be compound or complex, depending on the extent of morphodifferentiation or their resemblance to normal teeth. The etiology of odontoma is unknown, although several theories have been proposed. This article describes a case of a large infected complex odontoma in the residual mandibular ridge, resulting in considerable mandibular expansion.

  12. Complex narratives

    NARCIS (Netherlands)

    Simons, J.

    2008-01-01

    This paper brings together narratology, game theory, and complexity theory to untangle the intricate nature of complex narratives in contemporary cinema. It interrogates the different terms - forking-path narratives, mind-game films, modular narratives, multiple-draft films, database narratives, puz

  13. Computational Complexity

    Directory of Open Access Journals (Sweden)

    J. A. Tenreiro Machado

    2017-02-01

    Full Text Available Complex systems (CS involve many elements that interact at different scales in time and space. The challenges in modeling CS led to the development of novel computational tools with applications in a wide range of scientific areas. The computational problems posed by CS exhibit intrinsic difficulties that are a major concern in Computational Complexity Theory. [...

  14. Managing Complexity

    DEFF Research Database (Denmark)

    Maylath, Bruce; Vandepitte, Sonia; Minacori, Patricia

    2013-01-01

    This article discusses the largest and most complex international learning-by-doing project to date- a project involving translation from Danish and Dutch into English and editing into American English alongside a project involving writing, usability testing, and translation from English into Dut...... and into French. The complexity of the undertaking proved to be a central element in the students' learning, as the collaboration closely resembles the complexity of international documentation workplaces of language service providers. © Association of Teachers of Technical Writing....

  15. Complex variables

    CERN Document Server

    Fisher, Stephen D

    1999-01-01

    The most important topics in the theory and application of complex variables receive a thorough, coherent treatment in this introductory text. Intended for undergraduates or graduate students in science, mathematics, and engineering, this volume features hundreds of solved examples, exercises, and applications designed to foster a complete understanding of complex variables as well as an appreciation of their mathematical beauty and elegance. Prerequisites are minimal; a three-semester course in calculus will suffice to prepare students for discussions of these topics: the complex plane, basic

  16. 基于静息态功能磁共振成像的慢性嗜酒者双侧杏仁核全脑功能连接研究%Whole brain functional connectivity of the bilateral amygdaloid in chronic alcoholics: a resting-state functional magnetic resonance imaging study

    Institute of Scientific and Technical Information of China (English)

    赵益林; 陈军; 刘金欢; 林雪; 吴汉斌; 徐良洲; 许启仲; 刘昌盛; 邱丽

    2015-01-01

    Objective To explore the conditions of whole brain functional connectivity (FC) of the bilateral amygdaloid in resting state in chronic alcoholics.Methods Thirty-three chronic alcoholics and 36 healthy control subjects matched in gender,age,education and handedness,admitted to our hospital from October 2011 to October 2012,were enrolled as chronic alcoholics group and control group,respectively.All subjects were asked to perform both Michigan alcohol screening scale (MAST) and alcohol addiction scale (ADS) to ensure that the alcohol dependent individuals enrolled in this study reached moderate alcohol dependent.All subjects were performed MR imaging;DPARSF software was used to perform data processing which was based on MATLABE,SPM and REST operating environment.REST software was made use of the left amygdala activity peak voxel (-24,0,-16) and right amygdala peak voxel (24,0,16) as seeded region of interest to get the whole brain FC mapping.Rest Slice Viewer software within REST software package was used to view statistical results.Each time series of brain regions were extracted,and correlation analysis of MAST scores with ADS scores was performed and the corresponding correlation coefficient values were recorded.Results Finally,57 subjects (28 in chronic alcoholics group and 29 in control group) were enrolled after screening.As compared with that in the healthy controls,the FC of left pars opercularis gyri frontalis inferiorista,bilateral supramarginal gyrus,left thalamus,bilateral paracentral lobule,left precentral gyrus,right pars orbitalis gyri frontalis inferiois and right superior temporal gyrus was significantly increased in the left amygdaloid,and that of left middle occipital gyrus,left cerebellar peduncle,left orbitofrontal region,left entorhinal cortex,right cerebellum inferior semi-Lunar lobule,right cerebellar parietal and superior frontal gyrus was significantly decreased in resting state in chronic alcoholism (P<0.05);as compared with that in the

  17. Complex analysis

    CERN Document Server

    Freitag, Eberhard

    2005-01-01

    The guiding principle of this presentation of ``Classical Complex Analysis'' is to proceed as quickly as possible to the central results while using a small number of notions and concepts from other fields. Thus the prerequisites for understanding this book are minimal; only elementary facts of calculus and algebra are required. The first four chapters cover the essential core of complex analysis: - differentiation in C (including elementary facts about conformal mappings) - integration in C (including complex line integrals, Cauchy's Integral Theorem, and the Integral Formulas) - sequences and series of analytic functions, (isolated) singularities, Laurent series, calculus of residues - construction of analytic functions: the gamma function, Weierstrass' Factorization Theorem, Mittag-Leffler Partial Fraction Decomposition, and -as a particular highlight- the Riemann Mapping Theorem, which characterizes the simply connected domains in C. Further topics included are: - the theory of elliptic functions based on...

  18. Complex Networks

    CERN Document Server

    Evsukoff, Alexandre; González, Marta

    2013-01-01

    In the last decade we have seen the emergence of a new inter-disciplinary field focusing on the understanding of networks which are dynamic, large, open, and have a structure sometimes called random-biased. The field of Complex Networks is helping us better understand many complex phenomena such as the spread of  deseases, protein interactions, social relationships, to name but a few. Studies in Complex Networks are gaining attention due to some major scientific breakthroughs proposed by network scientists helping us understand and model interactions contained in large datasets. In fact, if we could point to one event leading to the widespread use of complex network analysis is the availability of online databases. Theories of Random Graphs from Erdös and Rényi from the late 1950s led us to believe that most networks had random characteristics. The work on large online datasets told us otherwise. Starting with the work of Barabási and Albert as well as Watts and Strogatz in the late 1990s, we now know th...

  19. Complex chemistry with complex compounds

    Directory of Open Access Journals (Sweden)

    Eichler Robert

    2016-01-01

    Full Text Available In recent years gas-phase chemical studies assisted by physical pre-separation allowed for the investigation of fragile single molecular species by gas-phase chromatography. The latest success with the heaviest group 6 transactinide seaborgium is highlighted. The formation of a very volatile hexacarbonyl compound Sg(CO6 was observed similarly to its lighter homologues molybdenum and tungsten. The interactions of these gaseous carbonyl complex compounds with quartz surfaces were investigated by thermochromatography. Second-generation experiments are under way to investigate the intramolecular bond between the central metal atom of the complexes and the ligands addressing the influence of relativistic effects in the heaviest compounds. Our contribution comprises some aspects of the ongoing challenging experiments as well as an outlook towards other interesting compounds related to volatile complex compounds in the gas phase.

  20. Managing Complexity

    Energy Technology Data Exchange (ETDEWEB)

    Chassin, David P.; Posse, Christian; Malard, Joel M.

    2004-08-01

    Physical analogs have shown considerable promise for understanding the behavior of complex adaptive systems, including macroeconomics, biological systems, social networks, and electric power markets. Many of today’s most challenging technical and policy questions can be reduced to a distributed economic control problem. Indeed, economically-based control of large-scale systems is founded on the conjecture that the price-based regulation (e.g., auctions, markets) results in an optimal allocation of resources and emergent optimal system control. This paper explores the state of the art in the use physical analogs for understanding the behavior of some econophysical systems and to deriving stable and robust control strategies for them. In particular we review and discussion applications of some analytic methods based on the thermodynamic metaphor according to which the interplay between system entropy and conservation laws gives rise to intuitive and governing global properties of complex systems that cannot be otherwise understood.

  1. Topiramate reduces excitability in the basolateral amygdala by selectively inhibiting GluK1 (GluR5) kainate receptors on interneurons and positively modulating GABAA receptors on principal neurons.

    Science.gov (United States)

    Braga, Maria F M; Aroniadou-Anderjaska, Vassiliki; Li, He; Rogawski, Michael A

    2009-08-01

    Topiramate [2,3:4,5-bis-O-(1-methylethylidene)-beta-D-fructopyranose sulfamate] is a structurally novel antiepileptic drug that has broad efficacy in epilepsy, but the mechanisms underlying its therapeutic activity are not fully understood. We have found that topiramate selectively inhibits GluK1 (GluR5) kainate receptor-mediated excitatory postsynaptic responses in rat basolateral amygdala (BLA) principal neurons and protects against seizures induced by the GluK1 kainate receptor agonist (R,S)-2-amino-3-(3-hydroxy-5-tert-butylisoxazol-4-yl)propanoic acid (ATPA). Here, we demonstrate that topiramate also modulates inhibitory function in the BLA. Using whole-cell recordings in rat amygdala slices, we found that 0.3 to 10 microM topiramate 1) inhibited ATPA-evoked postsynaptic currents recorded from BLA interneurons; 2) suppressed ATPA-induced enhancement of spontaneous inhibitory postsynaptic currents (IPSCs) recorded from BLA pyramidal cells; and 3) blocked ATPA-induced suppression of evoked IPSCs, which is mediated by presynaptic GluK1 kainate receptors present on BLA interneurons. Topiramate (10 microM) had no effect on the AMPA [(R,S)-alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid]-induced enhancement of spontaneous activity of BLA neurons. Thus, although topiramate inhibits GluK1 kainate receptor-mediated enhancement of interneuron firing, it promotes evoked GABA release, leading to a net inhibition of circuit excitability. In addition, we found that topiramate (0.3-10 microM) increased the amplitude of evoked, spontaneous, and miniature IPSCs in BLA pyramidal neurons, indicating an enhancement of postsynaptic GABA(A) receptor responses. Taken together with our previous findings, we conclude that topiramate protects against hyperexcitability in the BLA by suppressing the GluK1 kainate receptor-mediated excitation of principal neurons by glutamatergic afferents, blocking the suppression of GABA release from interneurons mediated by presynaptic GluK1

  2. Differential involvement of medial prefrontal cortex and basolateral amygdala extracellular signal-regulated kinase in extinction of conditioned taste aversion is dependent on different intervals of extinction following conditioning.

    Science.gov (United States)

    Lin, P-Y; Wang, S-P; Tai, M-Y; Tsai, Y-F

    2010-11-24

    Extinction reflects a decrease in the conditioned response (CR) following non-reinforcement of a conditioned stimulus. Behavioral evidence indicates that extinction involves an inhibitory learning mechanism in which the extinguished CR reappears with presentation of an unconditioned stimulus. However, recent studies on fear conditioning suggest that extinction erases the original conditioning if the time interval between fear acquisition and extinction is short. The present study examined the effects of different intervals between acquisition and extinction of the original memory in conditioned taste aversion (CTA). Male Long-Evans rats acquired CTA by associating a 0.2% sucrose solution with malaise induced by i.p. injection of 4 ml/kg 0.15 M LiCl. Two different time intervals, 5 and 24 h, between CTA acquisition and extinction were used. Five or 24 h after CTA acquisition, extinction trials were performed, in which a bottle containing 20 ml of a 0.2% sucrose solution was provided for 10 min without subsequent LiCl injection. If sucrose consumption during the extinction trials was greater than the average water consumption, then rats were considered to have reached CTA extinction. Rats subjected to extinction trials lasting 24 h, but not 5 h, after acquisition re-exhibited the extinguished CR following injection of 0.15 M LiCl alone 7 days after acquisition. Extracellular signal-regulated kinase (ERK) in the medial prefrontal cortex (mPFC) and basolateral nucleus of the amygdala (BLA) was examined by Western blot after the first extinction trial. ERK activation in the mPFC was induced after the extinction trial beginning 5 h after acquisition, whereas the extinction trial performed 24 h after acquisition induced ERK activation in the BLA. These data suggest that the original conditioning can be inhibited or retained by CTA extinction depending on the time interval between acquisition and extinction and that the ERK transduction pathway in the mPFC and BLA is

  3. Complex variables

    CERN Document Server

    Flanigan, Francis J

    2010-01-01

    A caution to mathematics professors: Complex Variables does not follow conventional outlines of course material. One reviewer noting its originality wrote: ""A standard text is often preferred [to a superior text like this] because the professor knows the order of topics and the problems, and doesn't really have to pay attention to the text. He can go to class without preparation."" Not so here-Dr. Flanigan treats this most important field of contemporary mathematics in a most unusual way. While all the material for an advanced undergraduate or first-year graduate course is covered, discussion

  4. Complex dynamics

    CERN Document Server

    Carleson, Lennart

    1993-01-01

    Complex dynamics is today very much a focus of interest. Though several fine expository articles were available, by P. Blanchard and by M. Yu. Lyubich in particular, until recently there was no single source where students could find the material with proofs. For anyone in our position, gathering and organizing the material required a great deal of work going through preprints and papers and in some cases even finding a proof. We hope that the results of our efforts will be of help to others who plan to learn about complex dynamics and perhaps even lecture. Meanwhile books in the field a. re beginning to appear. The Stony Brook course notes of J. Milnor were particularly welcome and useful. Still we hope that our special emphasis on the analytic side will satisfy a need. This book is a revised and expanded version of notes based on lectures of the first author at UCLA over several \\Vinter Quarters, particularly 1986 and 1990. We owe Chris Bishop a great deal of gratitude for supervising the production of cour...

  5. Cosmic Complexity

    Science.gov (United States)

    Mather, John C.

    2012-01-01

    What explains the extraordinary complexity of the observed universe, on all scales from quarks to the accelerating universe? My favorite explanation (which I certainty did not invent) ls that the fundamental laws of physics produce natural instability, energy flows, and chaos. Some call the result the Life Force, some note that the Earth is a living system itself (Gaia, a "tough bitch" according to Margulis), and some conclude that the observed complexity requires a supernatural explanation (of which we have many). But my dad was a statistician (of dairy cows) and he told me about cells and genes and evolution and chance when I was very small. So a scientist must look for me explanation of how nature's laws and statistics brought us into conscious existence. And how is that seemll"!gly Improbable events are actually happening a!1 the time? Well, the physicists have countless examples of natural instability, in which energy is released to power change from simplicity to complexity. One of the most common to see is that cooling water vapor below the freezing point produces snowflakes, no two alike, and all complex and beautiful. We see it often so we are not amazed. But physlc!sts have observed so many kinds of these changes from one structure to another (we call them phase transitions) that the Nobel Prize in 1992 could be awarded for understanding the mathematics of their common features. Now for a few examples of how the laws of nature produce the instabilities that lead to our own existence. First, the Big Bang (what an insufficient name!) apparently came from an instability, in which the "false vacuum" eventually decayed into the ordinary vacuum we have today, plus the most fundamental particles we know, the quarks and leptons. So the universe as a whole started with an instability. Then, a great expansion and cooling happened, and the loose quarks, finding themselves unstable too, bound themselves together into today's less elementary particles like protons and

  6. Cosmic Complexity

    Science.gov (United States)

    Mather, John C.

    2012-01-01

    What explains the extraordinary complexity of the observed universe, on all scales from quarks to the accelerating universe? My favorite explanation (which I certainty did not invent) ls that the fundamental laws of physics produce natural instability, energy flows, and chaos. Some call the result the Life Force, some note that the Earth is a living system itself (Gaia, a "tough bitch" according to Margulis), and some conclude that the observed complexity requires a supernatural explanation (of which we have many). But my dad was a statistician (of dairy cows) and he told me about cells and genes and evolution and chance when I was very small. So a scientist must look for me explanation of how nature's laws and statistics brought us into conscious existence. And how is that seemll"!gly Improbable events are actually happening a!1 the time? Well, the physicists have countless examples of natural instability, in which energy is released to power change from simplicity to complexity. One of the most common to see is that cooling water vapor below the freezing point produces snowflakes, no two alike, and all complex and beautiful. We see it often so we are not amazed. But physlc!sts have observed so many kinds of these changes from one structure to another (we call them phase transitions) that the Nobel Prize in 1992 could be awarded for understanding the mathematics of their common features. Now for a few examples of how the laws of nature produce the instabilities that lead to our own existence. First, the Big Bang (what an insufficient name!) apparently came from an instability, in which the "false vacuum" eventually decayed into the ordinary vacuum we have today, plus the most fundamental particles we know, the quarks and leptons. So the universe as a whole started with an instability. Then, a great expansion and cooling happened, and the loose quarks, finding themselves unstable too, bound themselves together into today's less elementary particles like protons and

  7. Neural and Behavioral Correlates of PTSD and Alcohol Use

    Science.gov (United States)

    2014-12-01

    reproduction in any medium, provided the original work is properly cited. The Role of the Amygdala in Anxiety Disorders Gina L. Forster, Andrew M...Amygdala in Male Reproductive Behavior a Node in the Mammalian Social Behavior Network. Annals of the New York Academy of Sciences. 877, 242-257...the Basolateral and Central Amygdaloid Nuclei. Brain Res Bull . 71, 466-474. S0361- 9230(06)00305-4 [pii] 10.1016/j.brainresbull.2006.10.004. [85

  8. Hyper Space Complex Number

    OpenAIRE

    Tan, Shanguang

    2007-01-01

    A new kind of numbers called Hyper Space Complex Numbers and its algebras are defined and proved. It is with good properties as the classic Complex Numbers, such as expressed in coordinates, triangular and exponent forms and following the associative and commutative laws of addition and multiplication. So the classic Complex Number is developed from in complex plane with two dimensions to in complex space with N dimensions and the number system is enlarged also.

  9. Complex networks analysis of language complexity

    CERN Document Server

    Amancio, Diego R; Oliveira, Osvaldo N; Costa, Luciano da F; 10.1209/0295-5075/100/58002

    2013-01-01

    Methods from statistical physics, such as those involving complex networks, have been increasingly used in quantitative analysis of linguistic phenomena. In this paper, we represented pieces of text with different levels of simplification in co-occurrence networks and found that topological regularity correlated negatively with textual complexity. Furthermore, in less complex texts the distance between concepts, represented as nodes, tended to decrease. The complex networks metrics were treated with multivariate pattern recognition techniques, which allowed us to distinguish between original texts and their simplified versions. For each original text, two simplified versions were generated manually with increasing number of simplification operations. As expected, distinction was easier for the strongly simplified versions, where the most relevant metrics were node strength, shortest paths and diversity. Also, the discrimination of complex texts was improved with higher hierarchical network metrics, thus point...

  10. Irinotecan Lipid Complex Injection

    Science.gov (United States)

    Irinotecan lipid complex is used in combination with other medications to treat pancreatic cancer that has spread to other ... worsened after treatment with other chemotherapy medications. Irinotecan lipid complex is in a class of antineoplastic medications ...

  11. Doxorubicin Lipid Complex Injection

    Science.gov (United States)

    Doxorubicin lipid complex is used to treat ovarian cancer that has not improved or that has worsened after treatment with other medications. Doxorubicin lipid complex is also used to treat Kaposi's sarcoma ( ...

  12. Daunorubicin Lipid Complex Injection

    Science.gov (United States)

    Daunorubicin lipid complex is used to treat advanced Kaposi's sarcoma (a type of cancer that causes abnormal tissue to ... body) related to acquired immunodeficiency syndrome (AIDS). Daunorubicin lipid complex is in a class of medications called ...

  13. Vincristine Lipid Complex Injection

    Science.gov (United States)

    Vincristine lipid complex is used to treat a certain type of acute lymphoblastic leukemia (ALL; a type of cancer ... least two different treatments with other medications. Vincristine lipid complex is in a class of medications called ...

  14. Oligocyclopentadienyl transition metal complexes

    Energy Technology Data Exchange (ETDEWEB)

    de Azevedo, Cristina G.; Vollhardt, K. Peter C.

    2002-01-18

    Synthesis, characterization, and reactivity studies of oligocyclopentadienyl transition metal complexes, namely those of fulvalene, tercyclopentadienyl, quatercyclopentadienyl, and pentacyclopentadienyl(cyclopentadienyl) are the subject of this account. Thermal-, photo-, and redox chemistries of homo- and heteropolynuclear complexes are described.

  15. Complexity Near Horizons

    CERN Document Server

    Halyo, Edi

    2015-01-01

    We generalize the concept of complexity near horizons to all nondegenerate black holes. For Schwarzschild black holes, we show that Rindler observers see a complexity change of $S$ during proper time $1/\\kappa$ which corresponds to the creation of a causal patch with proper length $1/\\kappa$ inside the horizon. We attempt to describe complexity in the horizon CFT and the Euclidean picture.

  16. Quaternionic versus complex maps

    Energy Technology Data Exchange (ETDEWEB)

    Asorey, M [Departamento de Fisica Teorica, Universidad de Zaragoza 50009 Zaragoza (Spain); Scolarici, G [Dipartimento di Fisica dell' Universita del Salento and INFN, Sezione di Lecce, I-73100 Lecce (Italy); Solombrino, L [Dipartimento di Fisica dell' Universita del Salento and INFN, Sezione di Lecce, I-73100 Lecce (Italy)

    2007-11-15

    We discuss the relation between completely positive quaternionic maps and the corresponding complex maps obtained via projection operation. In order to illustrate this formalism, we reobtain the (complex) qubit subdynamics of maximally entangled Bell states, as complex projection of unitary dynamics between quaternionic pure states.

  17. Complexity, Systems, and Software

    Science.gov (United States)

    2014-08-14

    complex ( Hidden issues; dumbs down operator) 11 Complexity, Systems, and Software Sarah Sheard August 14, 2014 © 2014 Carnegie...August 14, 2014 © 2014 Carnegie Mellon University Addressing Complexity in SoSs Source: SEBOK Wiki System Con truer Strateglc Context

  18. OFD1 and flotillins are integral components of a ciliary signaling protein complex organized by polycystins in renal epithelia and odontoblasts.

    Directory of Open Access Journals (Sweden)

    Stephanie Jerman

    Full Text Available Mutation of the X-linked oral-facial-digital syndrome type 1 (OFD1 gene is embryonic lethal in males and results in craniofacial malformations and adult onset polycystic kidney disease in females. While the OFD1 protein localizes to centriolar satellites, centrosomes and basal bodies, its cellular function and how it relates to cystic kidney disease is largely unknown. Here, we demonstrate that OFD1 is assembled into a protein complex that is localized to the primary cilium and contains the epidermal growth factor receptor (EGFR and domain organizing flotillin proteins. This protein complex, which has similarity to a basolateral adhesion domain formed during cell polarization, also contains the polycystin proteins that when mutant cause autosomal dominant polycystic kidney disease (ADPKD. Importantly, in human ADPKD cells where mutant polycystin-1 fails to localize to cilia, there is a concomitant loss of localization of polycystin-2, OFD1, EGFR and flotillin-1 to cilia. Together, these data suggest that polycystins are necessary for assembly of a novel flotillin-containing ciliary signaling complex and provide a molecular rationale for the common renal pathologies caused by OFD1 and PKD mutations.

  19. SYSTEMS WITH COMPLEXITY

    Institute of Scientific and Technical Information of China (English)

    WANG Chenghong; ZHANG Lijun

    2004-01-01

    Science of Complexity is a newly emerging branch of natural scienceAlthoughwe still haven't a precise definition, there are some principles for justifying whether a systemis a complex systemThe purpose of this article is to reveal some of such principlesOnthe basis of them, the concept of a system with complexity is proposedThey may helpus to distinguish a real complex system from complicated objects in common senseThenwe propose some fundamental problems faced by the study of systems with complexity.

  20. Complex variables I essentials

    CERN Document Server

    Solomon, Alan D

    2013-01-01

    REA's Essentials provide quick and easy access to critical information in a variety of different fields, ranging from the most basic to the most advanced. As its name implies, these concise, comprehensive study guides summarize the essentials of the field covered. Essentials are helpful when preparing for exams, doing homework and will remain a lasting reference source for students, teachers, and professionals. Complex Variables I includes functions of a complex variable, elementary complex functions, integrals of complex functions in the complex plane, sequences and series, and poles and r

  1. Complexity Through Nonextensivity

    CERN Document Server

    Bialek, W; Tishby, N; Bialek, William; Nemenman, Ilya; Tishby, Naftali

    2001-01-01

    The problem of defining and studying complexity of a time series has interested people for years. In the context of dynamical systems, Grassberger has suggested that a slow approach of the entropy to its extensive asymptotic limit is a sign of complexity. We investigate this idea further by information theoretic and statistical mechanics techniques and show that these arguments can be made precise, and that they generalize many previous approaches to complexity, in particular unifying ideas from the physics literature with ideas from learning and coding theory; there are even connections of this statistical approach to algorithmic or Kolmogorov complexity. Moreover, a set of simple axioms similar to those used by Shannon in his development of information theory allows us to prove that the divergent part of the subextensive component of the entropy is a unique complexity measure. We classify time series by their complexities and demonstrate that beyond the `logarithmic' complexity classes widely anticipated in...

  2. Photocytotoxic lanthanide complexes

    Indian Academy of Sciences (India)

    Akhtar Hussain; Akhil R Chakravarty

    2012-11-01

    Lanthanide complexes have recently received considerable attention in the field of therapeutic and diagnostic medicines. Among many applications of lanthanides, gadolinium complexes are used as magnetic resonance imaging (MRI) contrast agents in clinical radiology and luminescent lanthanides for bioanalysis, imaging and sensing. The chemistry of photoactive lanthanide complexes showing biological applications is of recent origin. Photodynamic therapy (PDT) is a non-invasive treatment modality of cancer using a photosensitizer drug and light. This review primarily focuses on different aspects of the chemistry of lanthanide complexes showing photoactivated DNA cleavage activity and cytotoxicity in cancer cells. Macrocyclic texaphyrin-lanthanide complexes are known to show photocytotoxicity with the PDT effect in near-IR light. Very recently, non-macrocyclic lanthanide complexes are reported to show photocytotoxicity in cancer cells. Attempts have been made in this perspective article to review and highlight the photocytotoxic behaviour of various lanthanide complexes for their potential photochemotherapeutic applications.

  3. On Complex Random Variables

    Directory of Open Access Journals (Sweden)

    Anwer Khurshid

    2012-07-01

    Full Text Available Normal 0 false false false EN-US X-NONE X-NONE In this paper, it is shown that a complex multivariate random variable  is a complex multivariate normal random variable of dimensionality if and only if all nondegenerate complex linear combinations of  have a complex univariate normal distribution. The characteristic function of  has been derived, and simpler forms of some theorems have been given using this characterization theorem without assuming that the variance-covariance matrix of the vector  is Hermitian positive definite. Marginal distributions of  have been given. In addition, a complex multivariate t-distribution has been defined and the density derived. A characterization of the complex multivariate t-distribution is given. A few possible uses of this distribution have been suggested.

  4. Measuring static complexity

    Directory of Open Access Journals (Sweden)

    Ben Goertzel

    1992-01-01

    Full Text Available The concept of “pattern” is introduced, formally defined, and used to analyze various measures of the complexity of finite binary sequences and other objects. The standard Kolmogoroff-Chaitin-Solomonoff complexity measure is considered, along with Bennett's ‘logical depth’, Koppel's ‘sophistication'’, and Chaitin's analysis of the complexity of geometric objects. The pattern-theoretic point of view illuminates the shortcomings of these measures and leads to specific improvements, it gives rise to two novel mathematical concepts--“orders” of complexity and “levels” of pattern, and it yields a new measure of complexity, the “structural complexity”, which measures the total amount of structure an entity possesses.

  5. Simplicial complexes of graphs

    CERN Document Server

    Jonsson, Jakob

    2008-01-01

    A graph complex is a finite family of graphs closed under deletion of edges. Graph complexes show up naturally in many different areas of mathematics, including commutative algebra, geometry, and knot theory. Identifying each graph with its edge set, one may view a graph complex as a simplicial complex and hence interpret it as a geometric object. This volume examines topological properties of graph complexes, focusing on homotopy type and homology. Many of the proofs are based on Robin Forman's discrete version of Morse theory. As a byproduct, this volume also provides a loosely defined toolbox for attacking problems in topological combinatorics via discrete Morse theory. In terms of simplicity and power, arguably the most efficient tool is Forman's divide and conquer approach via decision trees; it is successfully applied to a large number of graph and digraph complexes.

  6. Complex networks and computing

    Institute of Scientific and Technical Information of China (English)

    Shuigeng ZHOU; Zhongzhi ZHANG

    2009-01-01

    @@ Nowadays complex networks are pervasive in various areas of science and technology. Popular examples of complex networks include the Internet, social networks of collaboration, citations and co-authoring, as well as biological networks such as gene and protein interactions and others. Complex networks research spans across mathematics, computer science, engineering, biology and the social sciences. Even in computer science area, increasing problems are either found to be related to complex networks or studied from the perspective of complex networks, such as searching on Web and P2P networks, routing in sensor networks, language processing, software engineering etc. The interaction and mergence of complex networks and computing is inspiring new chances and challenges in computer science.

  7. Recognizing dualizing complexes

    OpenAIRE

    Jorgensen, Peter

    2003-01-01

    Let A be a noetherian local commutative ring and let M be a suitable complex of A-modules. This paper proves that M is a dualizing complex for A if and only if the trivial extension A \\ltimes M is a Gorenstein Differential Graded Algebra. As a corollary follows that A has a dualizing complex if and only if it is a quotient of a Gorenstein local Differential Graded Algebra.

  8. Complex Systems and Dependability

    CERN Document Server

    Zamojski, Wojciech; Sugier, Jaroslaw

    2012-01-01

    Typical contemporary complex system is a multifaceted amalgamation of technical, information, organization, software and human (users, administrators and management) resources. Complexity of such a system comes not only from its involved technical and organizational structure but mainly from complexity of information processes that must be implemented in the operational environment (data processing, monitoring, management, etc.). In such case traditional methods of reliability analysis focused mainly on technical level are usually insufficient in performance evaluation and more innovative meth

  9. Genetics of complex diseases.

    Science.gov (United States)

    Motulsky, Arno G

    2006-02-01

    Approaches to the study of the genetic basis of common complex diseases and their clinical applications are considered. Monogenic Mendelian inheritance in such conditions is infrequent but its elucidation may help to detect pathogenic mechanisms in the more common variety of complex diseases. Involvement by multiple genes in complex diseases usually occurs but the isolation and identification of specific genes so far has been exceptional. The role of common polymorphisms as indicators of disease risk in various studies is discussed.

  10. The role of technical, biological, and pharmacological factors in the laboratory evaluation of anticonvulsant drugs. V. Lack of seasonal influences on amygdala kindling in rats.

    Science.gov (United States)

    Wlaź, P; Löscher, W

    1993-10-01

    Previous studies have suggested that seizure models may be affected by seasonal rhythms, even under controlled environmental conditions. In the present experiments in rats with chronically implanted electrodes in the basolateral amygdala, kindling was initiated at different seasons of the year over a period of 3 years. In a total of 109 animals, the following parameters were determined: the threshold for induction of amygdaloid afterdischarges prior to kindling (pre-kindling ADT), the number of daily amygdaloid stimulations to fully kindled (stage 5) seizures, and the post-kindling ADT. No seasonal influences were found with respect to rate of kindling development and post-kindling ADT. In contrast, pre-kindling ADTs appeared to be higher in spring than in other seasons, which, however, could not be reproduced in another spring. Thus, the data do not indicate that seasonal rhythms affect the kindling model of epilepsy.

  11. Berger Engineering Complex

    Data.gov (United States)

    Federal Laboratory Consortium — Description/History: Engineering laboratory The Berger Lab Complex is a multi-purpose building with professional office, 100 seat auditorium, general purpose labs,...

  12. Higher Koszul complexes

    Institute of Scientific and Technical Information of China (English)

    叶郁; 张璞

    2003-01-01

    In this paper we generalize the Koszul complexes and Koszul algebras, and introduce the higherKoszul (t-Koszul) complexes and higher Koszul algebras, where t ≥ 2 is an integer. We prove that an algebra ist-Koszul if and only if its t-Koszul complex is augmented, i.e. the higher degree (≥ 1) homologies vanish. Forarbitrary t-Koszul algebra , we also give a description of the structure of the cohomology algebra Ext ( 0, 0)by using the t-Koszul complexes, where the 0 is the direct sum of the simples.

  13. Introductory complex analysis

    CERN Document Server

    Silverman, Richard A

    1984-01-01

    A shorter version of A. I. Markushevich's masterly three-volume Theory of Functions of a Complex Variable, this edition is appropriate for advanced undergraduate and graduate courses in complex analysis. Numerous worked-out examples and more than 300 problems, some with hints and answers, make it suitable for independent study. 1967 edition.

  14. Complexity, Robustness, and Performance

    NARCIS (Netherlands)

    B. Visser (Bauke)

    2002-01-01

    textabstractThis paper analyses the relationship between organizational complexity ( the degree of detail of information necessary to correctly assign agents to positions), robustness (the relative loss of performance due to mis-allocated agents), and performance. More complex structures are not nec

  15. The visibility complex

    NARCIS (Netherlands)

    Pocchiola, M; Vegter, G

    1996-01-01

    We introduce the visibility complex (rr 2-dimensional regular cell complex) of a collection of n pairwise disjoint convex obstacles in the plane. It can be considered as a subdivision of the set of free rays (i.e., rays whose origins lie in free space, the complement of the obstacles). Its cells cor

  16. Complexity and Relations

    Science.gov (United States)

    Lancaster, Jeanette Elizabeth

    2013-01-01

    A central feature of complexity is that it is based on non-linear, recursive relations. However, in most current accounts of complexity such relations, while non-linear, are based on the reductive relations of a Newtonian onto-epistemological framework. This means that the systems that are emergent from the workings of such relations are a…

  17. Schools and Complexity

    Science.gov (United States)

    Trombly, Christopher E.

    2014-01-01

    As schools, districts, and the overall education system are complex entities, both the approaches taken to improve them and the methods used to study them must be similarly complex. Simple solutions imposed with no regard for schools' or districts' unique contexts hold little promise, while seemingly insignificant differences between those…

  18. Visual Complexity: A Review

    Science.gov (United States)

    Donderi, Don C.

    2006-01-01

    The idea of visual complexity, the history of its measurement, and its implications for behavior are reviewed, starting with structuralism and Gestalt psychology at the beginning of the 20th century and ending with visual complexity theory, perceptual learning theory, and neural circuit theory at the beginning of the 21st. Evidence is drawn from…

  19. Conducting metal dithiolate complexes

    DEFF Research Database (Denmark)

    Underhill, A. E.; Ahmad, M. M.; Turner, D. J.;

    1985-01-01

    Further work on the chemical composition of the one-dimensional metallic metal dithiolene complex Li-Pt(mnt) is reported. The electrical conduction and thermopower properties of the nickel and palladium complexes are reported and compared with those of the platinum compound...

  20. Comments on Holographic Complexity

    CERN Document Server

    Carmi, Dean; Rath, Pratik

    2016-01-01

    We study two recent conjectures for holographic complexity: the complexity=action conjecture and the complexity=volume conjecture. In particular, we examine the structure of the UV divergences appearing in these quantities, and show that the coefficients can be written as local integrals of geometric quantities in the boundary. We also consider extending these conjectures to evaluate the complexity of the mixed state produced by reducing the pure global state to a specific subregion of the boundary time slice. The UV divergences in this subregion complexity have a similar geometric structure, but there are also new divergences associated with the geometry of the surface enclosing the boundary region of interest. We discuss possible implications arising from the geometric nature of these UV divergences.

  1. Supporting complex search tasks

    DEFF Research Database (Denmark)

    Gäde, Maria; Hall, Mark; Huurdeman, Hugo

    2015-01-01

    There is broad consensus in the field of IR that search is complex in many use cases and applications, both on the Web and in domain specific collections, and both professionally and in our daily life. Yet our understanding of complex search tasks, in comparison to simple look up tasks, is fragme......There is broad consensus in the field of IR that search is complex in many use cases and applications, both on the Web and in domain specific collections, and both professionally and in our daily life. Yet our understanding of complex search tasks, in comparison to simple look up tasks......, and recommendations, and supporting exploratory search to sensemaking and analytics, UI and UX design pose an overconstrained challenge. How do we know that our approach is any good? Supporting complex search task requires new collaborations across the whole field of IR, and the proposed workshop will bring together...

  2. Leading healthcare in complexity.

    Science.gov (United States)

    Cohn, Jeffrey

    2014-12-01

    Healthcare institutions and providers are in complexity. Networks of interconnections from relationships and technology create conditions in which interdependencies and non-linear dynamics lead to surprising, unpredictable outcomes. Previous effective approaches to leadership, focusing on top-down bureaucratic methods, are no longer effective. Leading in complexity requires leaders to accept the complexity, create an adaptive space in which innovation and creativity can flourish and then integrate the successful practices that emerge into the formal organizational structure. Several methods for doing adaptive space work will be discussed. Readers will be able to contrast traditional leadership approaches with leading in complexity. They will learn new behaviours that are required of complexity leaders, along with challenges they will face, often from other leaders within the organization.

  3. Human kidney anion exchanger 1 interacts with adaptor-related protein complex 1 {mu}1A (AP-1 mu1A)

    Energy Technology Data Exchange (ETDEWEB)

    Sawasdee, Nunghathai; Junking, Mutita [Division of Medical Molecular Biology and BIOTEC-Medical Biotechnology Unit, Department of Research and Development, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700 (Thailand); Ngaojanlar, Piengpaga [Division of Medical Molecular Biology and BIOTEC-Medical Biotechnology Unit, Department of Research and Development, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700 (Thailand); Department of Immunology and Graduate Program in Immunology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700 (Thailand); Sukomon, Nattakan; Ungsupravate, Duangporn [Division of Medical Molecular Biology and BIOTEC-Medical Biotechnology Unit, Department of Research and Development, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700 (Thailand); Limjindaporn, Thawornchai [Division of Medical Molecular Biology and BIOTEC-Medical Biotechnology Unit, Department of Research and Development, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700 (Thailand); Department of Anatomy, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700 (Thailand); Akkarapatumwong, Varaporn [Institute of Molecular Biosciences, Mahidol University at Salaya Campus, Nakorn Pathom 73170 (Thailand); Noisakran, Sansanee [Division of Medical Molecular Biology and BIOTEC-Medical Biotechnology Unit, Department of Research and Development, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700 (Thailand); Yenchitsomanus, Pa-thai, E-mail: grpye@mahidol.ac.th [Division of Medical Molecular Biology and BIOTEC-Medical Biotechnology Unit, Department of Research and Development, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700 (Thailand)

    2010-10-08

    Research highlights: {yields} Trafficking defect of kAE1 is a cause of dRTA but trafficking pathway of kAE1 has not been clearly described. {yields} Adaptor-related protein complex 1 {mu}1A (AP-1 mu1A) was firstly reported to interact with kAE1. {yields} The interacting site for AP-1 mu1A on Ct-kAE1 was found to be Y904DEV907, a subset of YXXO motif. {yields} AP-1 mu1A knockdown showed a marked reduction of kAE1 on the cell membrane and its accumulation in endoplasmic reticulum. {yields} AP-1 mu1A has a critical role in kAE1 trafficking to the plasma membrane. -- Abstract: Kidney anion exchanger 1 (kAE1) mediates chloride (Cl{sup -}) and bicarbonate (HCO{sub 3}{sup -}) exchange at the basolateral membrane of kidney {alpha}-intercalated cells. Impaired trafficking of kAE1 leads to defect of the Cl{sup -}/HCO{sub 3}{sup -} exchange at the basolateral membrane and failure of proton (H{sup +}) secretion at the apical membrane, causing a kidney disease - distal renal tubular acidosis (dRTA). To gain a better insight into kAE1 trafficking, we searched for proteins physically interacting with the C-terminal region of kAE1 (Ct-kAE1), which contains motifs crucial for intracellular trafficking, by a yeast two-hybrid (Y2H) system. An adaptor-related protein complex 1 {mu}1A (AP-1 mu1A) subunit was found to interact with Ct-kAE1. The interaction between either Ct-kAE1 or full-length kAE1 and AP-1 mu1A were confirmed in human embryonic kidney (HEK) 293T by co-immunoprecipitation, affinity co-purification, co-localization, yellow fluorescent protein (YFP)-based protein fragment complementation assay (PCA) and GST pull-down assay. The interacting site for AP-1 mu1A on Ct-kAE1 was found to be Y904DEV907, a subset of YXXO motif. Interestingly, suppression of endogenous AP-1 mu1A in HEK 293T by small interfering RNA (siRNA) decreased membrane localization of kAE1 and increased its intracellular accumulation, suggesting for the first time that AP-1 mu1A is involved in the kAE1

  4. Controllability of Complex Systems

    Science.gov (United States)

    Slotine, Jean-Jacques

    2013-03-01

    We review recent work on controllability of complex systems. We also discuss the interplay of our results with questions of synchronization, and point out key directions of future research. Work done in collaboration with Yang-Yu Liu, Center for Complex Network Research and Departments of Physics, Computer Science and Biology, Northeastern University and Center for Cancer Systems Biology, Dana-Farber Cancer Institute; and Albert-László Barabási, Center for Complex Network Research and Departments of Physics, Computer Science and Biology, Northeastern University; Center for Cancer Systems Biology, Dana-Farber Cancer Institute; and Department of Medicine, Brigham and Women's Hospital, Harvard Medical School.

  5. Low complexity MIMO receivers

    CERN Document Server

    Bai, Lin; Yu, Quan

    2014-01-01

    Multiple-input multiple-output (MIMO) systems can increase the spectral efficiency in wireless communications. However, the interference becomes the major drawback that leads to high computational complexity at both transmitter and receiver. In particular, the complexity of MIMO receivers can be prohibitively high. As an efficient mathematical tool to devise low complexity approaches that mitigate the interference in MIMO systems, lattice reduction (LR) has been widely studied and employed over the last decade. The co-authors of this book are world's leading experts on MIMO receivers, and here they share the key findings of their research over years. They detail a range of key techniques for receiver design as multiple transmitted and received signals are available. The authors first introduce the principle of signal detection and the LR in mathematical aspects. They then move on to discuss the use of LR in low complexity MIMO receiver design with respect to different aspects, including uncoded MIMO detection...

  6. Complex Regional Pain Syndrome

    Science.gov (United States)

    Complex regional pain syndrome (CRPS) is a chronic pain condition. It causes intense pain, usually in the arms, hands, legs, or feet. ... in skin temperature, color, or texture Intense burning pain Extreme skin sensitivity Swelling and stiffness in affected ...

  7. Supporting complex search tasks

    DEFF Research Database (Denmark)

    Gäde, Maria; Hall, Mark; Huurdeman, Hugo;

    2015-01-01

    There is broad consensus in the field of IR that search is complex in many use cases and applications, both on the Web and in domain specific collections, and both professionally and in our daily life. Yet our understanding of complex search tasks, in comparison to simple look up tasks......, is fragmented at best. The workshop addressed the many open research questions: What are the obvious use cases and applications of complex search? What are essential features of work tasks and search tasks to take into account? And how do these evolve over time? With a multitude of information, varying from...... introductory to specialized, and from authoritative to speculative or opinionated, when to show what sources of information? How does the information seeking process evolve and what are relevant differences between different stages? With complex task and search process management, blending searching, browsing...

  8. A complex legacy

    Science.gov (United States)

    Moore, Cristopher

    2011-11-01

    In his tragically short life, Alan Turing helped define what computing machines are capable of, and where they reach inherent limits. His legacy is still felt every day, in areas ranging from computational complexity theory to cryptography and quantum computing.

  9. Physical Sciences Complex

    Data.gov (United States)

    Federal Laboratory Consortium — This 88,000 square foot complex is used to investigate basic physical science in support of missile technology development. It incorporates office space, dedicated...

  10. Management recommendations: Tewaukon Complex

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document is a review of land management practices at the Tewaukon Complex, by a land use specialist. Recommendations, time frame and additional comments are...

  11. Complex coacervate core micelles.

    Science.gov (United States)

    Voets, Ilja K; de Keizer, Arie; Cohen Stuart, Martien A

    2009-01-01

    In this review we present an overview of the literature on the co-assembly of neutral-ionic block, graft, and random copolymers with oppositely charged species in aqueous solution. Oppositely charged species include synthetic (co)polymers of various architectures, biopolymers - such as proteins, enzymes and DNA - multivalent ions, metallic nanoparticles, low molecular weight surfactants, polyelectrolyte block copolymer micelles, metallo-supramolecular polymers, equilibrium polymers, etcetera. The resultant structures are termed complex coacervate core/polyion complex/block ionomer complex/interpolyelectrolyte complex micelles (or vesicles); i.e., in short C3Ms (or C3Vs) and PIC, BIC or IPEC micelles (and vesicles). Formation, structure, dynamics, properties, and function will be discussed. We focus on experimental work; theory and modelling will not be discussed. Recent developments in applications and micelles with heterogeneous coronas are emphasized.

  12. Quantum Kolmogorov Complexity

    CERN Document Server

    Berthiaume, A; Laplante, S; Berthiaume, Andre; Dam, Wim van; Laplante, Sophie

    2000-01-01

    In this paper we give a definition for quantum Kolmogorov complexity. In the classical setting, the Kolmogorov complexity of a string is the length of the shortest program that can produce this string as its output. It is a measure of the amount of innate randomness (or information) contained in the string. We define the quantum Kolmogorov complexity of a qubit string as the length of the shortest quantum input to a universal quantum Turing machine that produces the initial qubit string with high fidelity. The definition of Vitanyi (Proceedings of the 15th IEEE Annual Conference on Computational Complexity, 2000) measures the amount of classical information, whereas we consider the amount of quantum information in a qubit string. We argue that our definition is natural and is an accurate representation of the amount of quantum information contained in a quantum state.

  13. Complexity for Artificial Substrates (

    NARCIS (Netherlands)

    Loke, L.H.L.; Jachowski, N.R.; Bouma, T.J.; Ladle, R.J.; Todd, P.A.

    2014-01-01

    Physical habitat complexity regulates the structure and function of biological communities, although the mechanisms underlying this relationship remain unclear. Urbanisation, pollution, unsustainable resource exploitation and climate change have resulted in the widespread simplification (and loss) o

  14. Complex Flow Workshop Report

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2012-05-01

    This report documents findings from a workshop on the impacts of complex wind flows in and out of wind turbine environments, the research needs, and the challenges of meteorological and engineering modeling at regional, wind plant, and wind turbine scales.

  15. On scattered subword complexity

    CERN Document Server

    Kása, Zoltán

    2011-01-01

    Special scattered subwords, in which the gaps are of length from a given set, are defined. The scattered subword complexity, which is the number of such scattered subwords, is computed for rainbow words.

  16. Complex and unpredictable Cardano

    Science.gov (United States)

    Ekert, Artur

    2008-08-01

    This purely recreational paper is about one of the most colorful characters of the Italian Renaissance, Girolamo Cardano, and the discovery of two basic ingredients of quantum theory, probability and complex numbers.

  17. Beyond complex Langevin equations

    CERN Document Server

    Wosiek, Jacek

    2016-01-01

    A simple integral relation between a complex weight and the corresponding positive distribution is derived by introducing a second complex variable. Together with the positivity and normalizability conditions, this sum rule allows to construct explicitly equivalent pairs of distributions in simple cases. In particular the well known solution for a complex gaussian distribution is generalized to an arbitrary complex slope. This opens a possibility of positive representation of Feynman path integrals directly in the Minkowski time. Such construction is then explicitly carried through in the second part of this presentation. The continuum limit of the new representation exists only if some of the additional couplings tend to infinity and are tuned in a specific way. The approach is then successfully applied to three quantum mechanical examples including a particle in a constant magnetic field -- a simplest prototype of a Wilson line. Further generalizations are shortly discussed and an amusing interpretation of ...

  18. Network Complexity of Foodwebs

    CERN Document Server

    Standish, Russell K

    2010-01-01

    In previous work, I have developed an information theoretic complexity measure of networks. When applied to several real world food webs, there is a distinct difference in complexity between the real food web, and randomised control networks obtained by shuffling the network links. One hypothesis is that this complexity surplus represents information captured by the evolutionary process that generated the network. In this paper, I test this idea by applying the same complexity measure to several well-known artificial life models that exhibit ecological networks: Tierra, EcoLab and Webworld. Contrary to what was found in real networks, the artificial life generated foodwebs had little information difference between itself and randomly shuffled versions.

  19. An erupted complex odontoma.

    Science.gov (United States)

    Tozoglu, Sinan; Yildirim, Umran; Buyukkurt, M Cemil

    2010-01-01

    Odontomas are benign tumors of odontogenic origin. The cause of the odontoma is unknown, but it is believed to be hereditary or due to a disturbance in tooth development triggered by trauma or infection. Odontomas may be either compound or complex. Although these tumors are seen frequently, erupted odontomas are rare. The purpose of this study is to present a rare case of complex odontoma that erupted into the oral cavity.

  20. Conversation, coupling and complexity

    DEFF Research Database (Denmark)

    Fusaroli, Riccardo; Abney, Drew; Bahrami, Bahador;

    We investigate the linguistic co-construction of interpersonal synergies. By applying a measure of coupling between complex systems to an experimentally elicited corpus of joint decision dialogues, we show that interlocutors’ linguistic behavior displays increasing signature of multi-scale coupling......, known as complexity matching, over the course of interaction. Furthermore, we show that stronger coupling corresponds with more effective interaction, as measured by collective task performance....

  1. Complex/Symplectic Mirrors

    CERN Document Server

    Chuang, W; Tomasiello, A; Chuang, Wu-yen; Kachru, Shamit; Tomasiello, Alessandro

    2005-01-01

    We construct a class of symplectic non--Kaehler and complex non--Kaehler string theory vacua, extending and providing evidence for an earlier suggestion by Polchinski and Strominger. The class admits a mirror pairing by construction. Comparing hints from a variety of sources, including ten--dimensional supergravity and KK reduction on SU(3)--structure manifolds, suggests a picture in which string theory extends Reid's fantasy to connect classes of both complex non-Kaehler and symplectic non-Kaehler manifolds.

  2. Quantum Hamiltonian Complexity

    OpenAIRE

    2014-01-01

    Constraint satisfaction problems are a central pillar of modern computational complexity theory. This survey provides an introduction to the rapidly growing field of Quantum Hamiltonian Complexity, which includes the study of quantum constraint satisfaction problems. Over the past decade and a half, this field has witnessed fundamental breakthroughs, ranging from the establishment of a "Quantum Cook-Levin Theorem" to deep insights into the structure of 1D low-temperature quantum systems via s...

  3. Electrospun complexes - functionalised nanofibres

    Science.gov (United States)

    Meyer, T.; Wolf, M.; Dreyer, B.; Unruh, D.; Krüger, C.; Menze, M.; Sindelar, R.; Klingelhöfer, G.; Renz, F.

    2016-12-01

    Here we present a new approach of using iron-complexes in electro-spun fibres. We modify poly(methyl methacrylate) (PMMA) by replacing the methoxy group with Diaminopropane or Ethylenediamine. The complex is bound covalently via an imine-bridge or an amide. The resulting polymer can be used in the electrospinning process without any further modifications in method either as pure reagent or mixed with small amounts of not functionalised polymer resulting in fibres of different qualities (Fig. 1).

  4. Complex variable HVPT

    Energy Technology Data Exchange (ETDEWEB)

    Killingbeck, John P [Mathematics Department, University of Hull, Hull HU6 7RX (United Kingdom); Grosjean, Alain [Laboratoire d' Astrophysique de l' Observatoire de Besancon (CNRS, UPRES-A 6091), 41 bis Avenue de l' Observatoire, BP 1615, 25010 Besancon Cedex (France); Jolicard, Georges [Laboratoire d' Astrophysique de l' Observatoire de Besancon (CNRS, UPRES-A 6091), 41 bis Avenue de l' Observatoire, BP 1615, 25010 Besancon Cedex (France)

    2004-08-13

    Complex variable hypervirial perturbation theory is applied to the case of oscillator and Coulomb potentials perturbed by a single term potential of the form Vx{sup n} or Vr{sup n}, respectively. The trial calculations reported show that this approach can produce accurate complex energies for resonant states via a simple and speedy calculation and can also be useful in studies of PT symmetry and tunnelling resonance effects. (addendum)

  5. Advances in network complexity

    CERN Document Server

    Dehmer, Matthias; Emmert-Streib, Frank

    2013-01-01

    A well-balanced overview of mathematical approaches to describe complex systems, ranging from chemical reactions to gene regulation networks, from ecological systems to examples from social sciences. Matthias Dehmer and Abbe Mowshowitz, a well-known pioneer in the field, co-edit this volume and are careful to include not only classical but also non-classical approaches so as to ensure topicality. Overall, a valuable addition to the literature and a must-have for anyone dealing with complex systems.

  6. MANAGEMENT OF SPORT COMPLEXES

    Directory of Open Access Journals (Sweden)

    Marian STAN

    2015-07-01

    Full Text Available The actuality of the investigated theme. Nowadays, human evolution, including his intellectual development, proves the fact that especially the creation manpower and the employment was the solution of all life’s ambitions in society. So, the fact is that in reality, man is the most important capital of the society. Also, in an individual’s life, the practice of sport plays a significant role and that’s why the initiation, the launch and the management of sports complexes activity reveal the existence of specific management features that we will identify and explain in the current study. The aim of the research refers to the elaboration of a theoretical base of the management of the sport complexes, to the pointing of the factors that influence the efficient existence and function of a sport complex in our country and to the determination of the responsibilities that have a manager who directs successfully the activity of the sport complexes. The investigation is based on theoretical methods, such as: scientific documentation, analysis, synthesis, comparison and on empirical research methods, like: study of researched literature and observation. The results of the research indicate the fact that the profitability of a sport complex must assure a particular structure to avoid the bankruptcy risk and also, that the administration of the sport complexes activity must keep in view the reliable functions of the contemporaneous management.

  7. Projectively related complex Finsler metrics

    CERN Document Server

    Aldea, Nicoleta

    2011-01-01

    In this paper we introduce in study the projectively related complex Finsler metrics. We prove the complex versions of the Rapcs\\'{a}k's theorem and characterize the weakly K\\"{a}hler and generalized Berwald projectively related complex Finsler metrics. The complex version of Hilbert's Fourth Problem is also pointed out. As an application, the projectiveness of a complex Randers metric is described.

  8. Complexity: The bigger picture

    CERN Document Server

    Vicsek, Tamás

    2010-01-01

    If a concept is not well defined, there are grounds for its abuse. This is particularly true of complexity, an inherently interdisciplinary concept that has penetrated very different fields of intellectual activity from physics to linguistics, but with no underlying, unified theory. Complexity has become a popular buzzword used in the hope of gaining attention or funding -- institutes and research networks associated with complex systems grow like mushrooms. Why and how did it happen that this vague notion has become a central motif in modern science? Is it only a fashion, a kind of sociological phenomenon, or is it a sign of a changing paradigm of our perception of the laws of nature and of the approaches required to understand them? Because virtually every real system is inherently extremely complicated, to say that a system is complex is almost an empty statement - couldn't an Institute of Complex Systems just as well be called an Institute for Almost Everything? Despite these valid concerns, the world is ...

  9. Algorithmic Relative Complexity

    Directory of Open Access Journals (Sweden)

    Daniele Cerra

    2011-04-01

    Full Text Available Information content and compression are tightly related concepts that can be addressed through both classical and algorithmic information theories, on the basis of Shannon entropy and Kolmogorov complexity, respectively. The definition of several entities in Kolmogorov’s framework relies upon ideas from classical information theory, and these two approaches share many common traits. In this work, we expand the relations between these two frameworks by introducing algorithmic cross-complexity and relative complexity, counterparts of the cross-entropy and relative entropy (or Kullback-Leibler divergence found in Shannon’s framework. We define the cross-complexity of an object x with respect to another object y as the amount of computational resources needed to specify x in terms of y, and the complexity of x related to y as the compression power which is lost when adopting such a description for x, compared to the shortest representation of x. Properties of analogous quantities in classical information theory hold for these new concepts. As these notions are incomputable, a suitable approximation based upon data compression is derived to enable the application to real data, yielding a divergence measure applicable to any pair of strings. Example applications are outlined, involving authorship attribution and satellite image classification, as well as a comparison to similar established techniques.

  10. Complexity and Dynamical Depth

    Directory of Open Access Journals (Sweden)

    Terrence Deacon

    2014-07-01

    Full Text Available We argue that a critical difference distinguishing machines from organisms and computers from brains is not complexity in a structural sense, but a difference in dynamical organization that is not well accounted for by current complexity measures. We propose a measure of the complexity of a system that is largely orthogonal to computational, information theoretic, or thermodynamic conceptions of structural complexity. What we call a system’s dynamical depth is a separate dimension of system complexity that measures the degree to which it exhibits discrete levels of nonlinear dynamical organization in which successive levels are distinguished by local entropy reduction and constraint generation. A system with greater dynamical depth than another consists of a greater number of such nested dynamical levels. Thus, a mechanical or linear thermodynamic system has less dynamical depth than an inorganic self-organized system, which has less dynamical depth than a living system. Including an assessment of dynamical depth can provide a more precise and systematic account of the fundamental difference between inorganic systems (low dynamical depth and living systems (high dynamical depth, irrespective of the number of their parts and the causal relations between them.

  11. Modeling Complex Time Limits

    Directory of Open Access Journals (Sweden)

    Oleg Svatos

    2013-01-01

    Full Text Available In this paper we analyze complexity of time limits we can find especially in regulated processes of public administration. First we review the most popular process modeling languages. There is defined an example scenario based on the current Czech legislature which is then captured in discussed process modeling languages. Analysis shows that the contemporary process modeling languages support capturing of the time limit only partially. This causes troubles to analysts and unnecessary complexity of the models. Upon unsatisfying results of the contemporary process modeling languages we analyze the complexity of the time limits in greater detail and outline lifecycles of a time limit using the multiple dynamic generalizations pattern. As an alternative to the popular process modeling languages there is presented PSD process modeling language, which supports the defined lifecycles of a time limit natively and therefore allows keeping the models simple and easy to understand.

  12. Philosophy of complex systems

    CERN Document Server

    2011-01-01

    The domain of nonlinear dynamical systems and its mathematical underpinnings has been developing exponentially for a century, the last 35 years seeing an outpouring of new ideas and applications and a concomitant confluence with ideas of complex systems and their applications from irreversible thermodynamics. A few examples are in meteorology, ecological dynamics, and social and economic dynamics. These new ideas have profound implications for our understanding and practice in domains involving complexity, predictability and determinism, equilibrium, control, planning, individuality, responsibility and so on. Our intention is to draw together in this volume, we believe for the first time, a comprehensive picture of the manifold philosophically interesting impacts of recent developments in understanding nonlinear systems and the unique aspects of their complexity. The book will focus specifically on the philosophical concepts, principles, judgments and problems distinctly raised by work in the domain of comple...

  13. Modeling Complex Systems

    CERN Document Server

    Boccara, Nino

    2010-01-01

    Modeling Complex Systems, 2nd Edition, explores the process of modeling complex systems, providing examples from such diverse fields as ecology, epidemiology, sociology, seismology, and economics. It illustrates how models of complex systems are built and provides indispensable mathematical tools for studying their dynamics. This vital introductory text is useful for advanced undergraduate students in various scientific disciplines, and serves as an important reference book for graduate students and young researchers. This enhanced second edition includes: . -recent research results and bibliographic references -extra footnotes which provide biographical information on cited scientists who have made significant contributions to the field -new and improved worked-out examples to aid a student’s comprehension of the content -exercises to challenge the reader and complement the material Nino Boccara is also the author of Essentials of Mathematica: With Applications to Mathematics and Physics (Springer, 2007).

  14. Complex Polynomial Vector Fields

    DEFF Research Database (Denmark)

    The two branches of dynamical systems, continuous and discrete, correspond to the study of differential equations (vector fields) and iteration of mappings respectively. In holomorphic dynamics, the systems studied are restricted to those described by holomorphic (complex analytic) functions...... vector fields. Since the class of complex polynomial vector fields in the plane is natural to consider, it is remarkable that its study has only begun very recently. There are numerous fundamental questions that are still open, both in the general classification of these vector fields, the decomposition...... of parameter spaces into structurally stable domains, and a description of the bifurcations. For this reason, the talk will focus on these questions for complex polynomial vector fields....

  15. Complex Strategic Choices

    DEFF Research Database (Denmark)

    Leleur, Steen

    Effective decision making requires a clear methodology, particularly in a complex world of globalisation. Institutions and companies in all disciplines and sectors are faced with increasingly multi-faceted areas of uncertainty which cannot always be effectively handled by traditional strategies....... Complex Strategic Choices provides clear principles and methods which can guide and support strategic decision making to face the many current challenges. By considering ways in which planning practices can be renewed and exploring the possibilities for acquiring awareness and tools to add value...... to strategic decision making, Complex Strategic Choices presents a methodology which is further illustrated by a number of case studies and example applications. Dr. Techn. Steen Leleur has adapted previously established research based on feedback and input from various conferences, journals and students...

  16. Nonergodic complexity management

    Science.gov (United States)

    Piccinini, Nicola; Lambert, David; West, Bruce J.; Bologna, Mauro; Grigolini, Paolo

    2016-06-01

    Linear response theory, the backbone of nonequilibrium statistical physics, has recently been extended to explain how and why nonergodic renewal processes are insensitive to simple perturbations, such as in habituation. It was established that a permanent correlation results between an external stimulus and the response of a complex system generating nonergodic renewal processes, when the stimulus is a similar nonergodic process. This is the principle of complexity management, whose proof relies on ensemble distribution functions. Herein we extend the proof to the nonergodic case using time averages and a single time series, hence making it usable in real life situations where ensemble averages cannot be performed because of the very nature of the complex systems being studied.

  17. Emergent Complex Network Geometry

    CERN Document Server

    Wu, Zhihao; Rahmede, Christoph; Bianconi, Ginestra

    2014-01-01

    Networks are mathematical structures that are universally used to describe a large variety of complex systems such as the brain or the Internet. Characterizing the geometrical properties of these networks has become increasingly relevant for routing problems, inference and data mining. In real growing networks, topological, structural and geometrical properties emerge spontaneously from their dynamical rules. Nevertheless we still miss a model in which networks develop an emergent complex geometry. Here we show that a single two parameter network model, the growing geometrical network, can generate complex network geometries with non-trivial distribution of curvatures, combining exponential growth and small-world properties with finite spectral dimensionality. In one limit, the non-equilibrium dynamical rules of these networks can generate scale-free networks with clustering and communities, in another limit planar random geometries with non-trivial modularity. Finally we find that these properties of the geo...

  18. Viral quasispecies complexity measures.

    Science.gov (United States)

    Gregori, Josep; Perales, Celia; Rodriguez-Frias, Francisco; Esteban, Juan I; Quer, Josep; Domingo, Esteban

    2016-06-01

    Mutant spectrum dynamics (changes in the related mutants that compose viral populations) has a decisive impact on virus behavior. The several platforms of next generation sequencing (NGS) to study viral quasispecies offer a magnifying glass to study viral quasispecies complexity. Several parameters are available to quantify the complexity of mutant spectra, but they have limitations. Here we critically evaluate the information provided by several population diversity indices, and we propose the introduction of some new ones used in ecology. In particular we make a distinction between incidence, abundance and function measures of viral quasispecies composition. We suggest a multidimensional approach (complementary information contributed by adequately chosen indices), propose some guidelines, and illustrate the use of indices with a simple example. We apply the indices to three clinical samples of hepatitis C virus that display different population heterogeneity. Areas of virus biology in which population complexity plays a role are discussed.

  19. The complex pendulum

    Science.gov (United States)

    Bender, Carl M.

    1999-07-01

    This talk proposes a generalization of conventional quantum mechanics. In conventional quantum mechanics one imposes the condition H †=H , where † represents complex conjugation and matrix transpose, to ensure that the Hamiltonian has a real spectrum. By replacing this mathematical condition with the weaker and more physical requirement H ‡=H , where ‡= PT represents combined parity reflection and time reversal, one obtains new infinite classes of complex Hamiltonians whose spectra are also real and positive. These PT-symmetric theories may be viewed as analytic continuations of conventional theories from real to complex-phase space. This talk describes the unusual classical and quantum properties of PT-symmetric quantum-mechanical and quantum-field-theoretic models.

  20. Emergy and ecosystem complexity

    Science.gov (United States)

    Ulgiati, Sergio; Brown, Mark T.

    2009-01-01

    The question "What drives complexity?" is addressed in this paper. To answer this question, we explore the way energy and material resources of different quality flow through ecosystems and support, directly and indirectly, ecosystems growth and development. Processes of resource transformation throughout the ecosystem build order, cycle materials, generate and sustain information. Energy drives all these processes and energetic principles explain much of what is observed, including energy degradation according to the laws of thermodynamics. Emergy, a quantitative measure of the global environmental work supporting ecosystem dynamics, is used here in order to provide a deeper understanding of complexity growth and decline in ecosystems. Ecosystem complexity is discussed in this paper in relation to changes in structure, organization and functional capacity, as explained by changes in emergy, empower, and transformity.

  1. Introduction to Complex Plasmas

    CERN Document Server

    Bonitz, Michael; Ludwig, Patrick

    2010-01-01

    Complex plasmas differ from traditional plasmas in many ways: these are low-temperature high pressure systems containing nanometer to micrometer size particles which may be highly charged and strongly interacting. The particles may be chemically reacting or be in contact with solid surfaces, and the electrons may show quantum behaviour. These interesting properties have led to many applications of complex plasmas in technology, medicine and science. Yet complex plasmas are extremely complicated, both experimentally and theoretically, and require a variety of new approaches which go beyond standard plasma physics courses. This book fills this gap presenting an introduction to theory, experiment and computer simulation in this field. Based on tutorial lectures at a very successful recent Summer Institute, the presentation is ideally suited for graduate students, plasma physicists and experienced undergraduates.

  2. Synchronization in complex networks

    Energy Technology Data Exchange (ETDEWEB)

    Arenas, A.; Diaz-Guilera, A.; Moreno, Y.; Zhou, C.; Kurths, J.

    2007-12-12

    Synchronization processes in populations of locally interacting elements are in the focus of intense research in physical, biological, chemical, technological and social systems. The many efforts devoted to understand synchronization phenomena in natural systems take now advantage of the recent theory of complex networks. In this review, we report the advances in the comprehension of synchronization phenomena when oscillating elements are constrained to interact in a complex network topology. We also overview the new emergent features coming out from the interplay between the structure and the function of the underlying pattern of connections. Extensive numerical work as well as analytical approaches to the problem are presented. Finally, we review several applications of synchronization in complex networks to different disciplines: biological systems and neuroscience, engineering and computer science, and economy and social sciences.

  3. Luminescent macrocyclic lanthanide complexes

    Science.gov (United States)

    Raymond, Kenneth N [Berkeley, CA; Corneillie, Todd M [Campbell, CA; Xu, Jide [Berkeley, CA

    2012-05-08

    The present invention provides a novel class of macrocyclic compounds as well as complexes formed between a metal (e.g., lanthanide) ion and the compounds of the invention. Preferred complexes exhibit high stability as well as high quantum yields of lanthanide ion luminescence in aqueous media without the need for secondary activating agents. Preferred compounds incorporate hydroxy-isophthalamide moieties within their macrocyclic structure and are characterized by surprisingly low, non-specific binding to a variety of polypeptides such as antibodies and proteins as well as high kinetic stability. These characteristics distinguish them from known, open-structured ligands.

  4. Complexity Equals Action

    CERN Document Server

    Brown, Adam R; Susskind, Leonard; Swingle, Brian; Zhao, Ying

    2015-01-01

    We conjecture that the quantum complexity of a holographic state is dual to the action of a certain spacetime region that we call a Wheeler-DeWitt patch. We illustrate and test the conjecture in the context of neutral, charged, and rotating black holes in AdS, as well as black holes perturbed with static shells and with shock waves. This conjecture evolved from a previous conjecture that complexity is dual to spatial volume, but appears to be a major improvement over the original. In light of our results, we discuss the hypothesis that black holes are the fastest computers in nature.

  5. Tuberous sclerosis complex.

    Science.gov (United States)

    DiMario, Francis J; Sahin, Mustafa; Ebrahimi-Fakhari, Darius

    2015-06-01

    Tuberous sclerosis complex is an autosomal-dominant, neurocutaneous, multisystem disorder characterized by cellular hyperplasia and tissue dysplasia. The genetic cause is mutations in the TSC1 gene, found on chromosome 9q34, and TSC2 gene, found on chromosome 16p13. The clinical phenotypes resulting from mutations in either of the 2 genes are variable in each individual. Herein, advances in the understanding of molecular mechanisms in tuberous sclerosis complex are reviewed, and current guidelines for diagnosis, treatment, follow-up, and management are summarized.

  6. Complex variables II essentials

    CERN Document Server

    Solomon, Alan D

    2013-01-01

    REA's Essentials provide quick and easy access to critical information in a variety of different fields, ranging from the most basic to the most advanced. As its name implies, these concise, comprehensive study guides summarize the essentials of the field covered. Essentials are helpful when preparing for exams, doing homework and will remain a lasting reference source for students, teachers, and professionals. Complex Variables II includes elementary mappings and Mobius transformation, mappings by general functions, conformal mappings and harmonic functions, applying complex functions to a

  7. Nonlinear dynamics and complexity

    CERN Document Server

    Luo, Albert; Fu, Xilin

    2014-01-01

    This important collection presents recent advances in nonlinear dynamics including analytical solutions, chaos in Hamiltonian systems, time-delay, uncertainty, and bio-network dynamics. Nonlinear Dynamics and Complexity equips readers to appreciate this increasingly main-stream approach to understanding complex phenomena in nonlinear systems as they are examined in a broad array of disciplines. The book facilitates a better understanding of the mechanisms and phenomena in nonlinear dynamics and develops the corresponding mathematical theory to apply nonlinear design to practical engineering.

  8. Resilience and Complexity

    DEFF Research Database (Denmark)

    Dahlberg, Rasmus

    2015-01-01

    This paper explores two key concepts: resilience and complexity. The first is understood as an emergent property of the latter, and their inter-relatedness is discussed using a three tier approach. First, by exploring the discourse of each concept, next, by analyzing underlying relationships and...... robust. Robustness is a property of simple or complicated systems characterized by predictable behavior, enabling the system to bounce back to its normal state following a perturbation. Resilience, however, is an emergent property of complex adaptive systems. It is suggested that this distinction...

  9. Complex/Symplectic Mirrors

    Energy Technology Data Exchange (ETDEWEB)

    Chuang, Wu-yen; Kachru, Shamit; /Stanford U., ITP /SLAC; Tomasiello, Alessandro; /Stanford U., ITP

    2005-10-28

    We construct a class of symplectic non-Kaehler and complex non-Kaehler string theory vacua, extending and providing evidence for an earlier suggestion by Polchinski and Strominger. The class admits a mirror pairing by construction. Comparing hints from a variety of sources, including ten-dimensional supergravity and KK reduction on SU(3)-structure manifolds, suggests a picture in which string theory extends Reid's fantasy to connect classes of both complex non-Kaehler and symplectic non-Kaehler manifolds.

  10. Complex function theory

    CERN Document Server

    Sarason, Donald

    2007-01-01

    Complex Function Theory is a concise and rigorous introduction to the theory of functions of a complex variable. Written in a classical style, it is in the spirit of the books by Ahlfors and by Saks and Zygmund. Being designed for a one-semester course, it is much shorter than many of the standard texts. Sarason covers the basic material through Cauchy's theorem and applications, plus the Riemann mapping theorem. It is suitable for either an introductory graduate course or an undergraduate course for students with adequate preparation. The first edition was published with the title Notes on Co

  11. Applied complex variables

    CERN Document Server

    Dettman, John W

    1965-01-01

    Analytic function theory is a traditional subject going back to Cauchy and Riemann in the 19th century. Once the exclusive province of advanced mathematics students, its applications have proven vital to today's physicists and engineers. In this highly regarded work, Professor John W. Dettman offers a clear, well-organized overview of the subject and various applications - making the often-perplexing study of analytic functions of complex variables more accessible to a wider audience. The first half of Applied Complex Variables, designed for sequential study, is a step-by-step treatment of fun

  12. Introduction to complex analysis

    CERN Document Server

    Priestley, H A

    2003-01-01

    Complex analysis is a classic and central area of mathematics, which is studied and exploited in a range of important fields, from number theory to engineering. Introduction to Complex Analysis was first published in 1985, and for this much awaited second edition the text has been considerably expanded, while retaining the style of the original. More detailed presentation is given of elementary topics, to reflect the knowledge base of current students. Exercise sets have beensubstantially revised and enlarged, with carefully graded exercises at the end of each chapter.This is the latest additi

  13. Complex HVPT and hyperasymptotics

    Energy Technology Data Exchange (ETDEWEB)

    Killingbeck, John P [Mathematics Department, University of Hull, Hull HU6 7RX (United Kingdom); Grosjean, Alain [Laboratoire d' Astrophysique de l' Observatoire de Besancon(CNRS, UMR 6091), 41 bis Avenue de l' Observatoire, BP 1615, 25010 Besancon Cedex (France); Jolicard, Georges [Laboratoire d' Astrophysique de l' Observatoire de Besancon(CNRS, UMR 6091), 41 bis Avenue de l' Observatoire, BP 1615, 25010 Besancon Cedex (France)

    2006-08-25

    Complex hypervirial perturbation theory (HVPT) is applied to the problem of a harmonic oscillator with a perturbation gx{sup 3}exp(i{psi}), for which the traditional Rayleigh-Schodinger perturbation theory has to be supplemented by hyperasymptotics for obtaining accurate resonance energies in the negative {psi} region. Complex HVPT gives accurate results for positive {psi} and for negative {psi} up to about vertical bar {phi} vertical bar = {pi}/24. The case of a quartic perturbed oscillator is also treated. (letter to the editor)

  14. Theories of computational complexity

    CERN Document Server

    Calude, C

    1988-01-01

    This volume presents four machine-independent theories of computational complexity, which have been chosen for their intrinsic importance and practical relevance. The book includes a wealth of results - classical, recent, and others which have not been published before.In developing the mathematics underlying the size, dynamic and structural complexity measures, various connections with mathematical logic, constructive topology, probability and programming theories are established. The facts are presented in detail. Extensive examples are provided, to help clarify notions and constructions. The lists of exercises and problems include routine exercises, interesting results, as well as some open problems.

  15. Salen complexes with dianionic counterions

    Energy Technology Data Exchange (ETDEWEB)

    Job, Gabriel E.; Farmer, Jay J.; Cherian, Anna E.

    2016-08-02

    The present invention describes metal salen complexes having dianionic counterions. Such complexes can be readily precipitated and provide an economical method for the purification and isolation of the complexes, and are useful to prepare novel polymer compositions.

  16. Genetics Home Reference: Carney complex

    Science.gov (United States)

    ... Understand Genetics Home Health Conditions Carney complex Carney complex Enable Javascript to view the expand/collapse boxes. Download PDF Open All Close All Description Carney complex is a disorder characterized by an increased risk ...

  17. Expression of Dbx1, Neurogenin 2, Semaphorin 5A, Cadherin 8, and Emx1 distinguish ventral and lateral pallial histogenetic divisions in the developing mouse claustroamygdaloid complex.

    Science.gov (United States)

    Medina, Loreta; Legaz, Isabel; González, Gertrudis; De Castro, Fernando; Rubenstein, John L R; Puelles, Luis

    2004-07-05

    We studied the lateral and ventral pallial divisions of the claustroamygdaloid complex by means of analysis of expression patterns of the developmental regulatory genes Tbr1, Dbx1, Neurogenin 2, Emx1, Cadherin 8, and Semaphorin 5A in mouse developing telencephalon, from embryonic day 12.5 until birth. Our results indicate that these genes help to distinguish distinct lateral and ventral pallial histogenetic divisions in the embryonic telencephalon. Tbr1 is broadly expressed in both lateral and ventral pallial histogenetic divisions (the lateroventral migratory stream plus the mantle) during early and intermediate embryonic development; its signal becomes weak in parts of the mantle during late embryonic development. Dbx1 is strongly and specifically expressed in progenitor cells (ventricular zone) of the ventral pallium during early embryonic development, but there is no signal of this gene in the rest of the pallium nor the subpallium. Neurogenin 2 and Semaphorin 5A are both expressed in a ventral subdivision of the lateroventral migratory stream (called by us the ventral migratory stream). Further, specific nuclei of the claustral complex and pallial amygdala show strong expression of Neurogenin 2 and/or Semaphorin 5A, including the ventromedial claustrum and endopiriform nuclei, the lateral and basomedial amygdalar nuclei, the anterior and posteromedial cortical amygdalar areas, plus the amygdalo-hippocampal area. We interpret these nuclei or areas of the claustroamygdaloid complex as possible derivatives of the ventral pallium. In contrast, during embryonic development the dorsolateral claustrum, the basolateral amygdalar nucleus, and the posterolateral cortical amygdalar area do not express or show weak expression of Neurogenin 2 or Semaphorin 5A, but express selectively and strongly Cadherin 8 plus Emx1, and may be derivatives of the lateral pallium. The lateral pallial and ventral pallial divisions of the claustroamygdaloid complex appear to have some

  18. Managing Complex Dynamical Systems

    Science.gov (United States)

    Cox, John C.; Webster, Robert L.; Curry, Jeanie A.; Hammond, Kevin L.

    2011-01-01

    Management commonly engages in a variety of research designed to provide insight into the motivation and relationships of individuals, departments, organizations, etc. This paper demonstrates how the application of concepts associated with the analysis of complex systems applied to such data sets can yield enhanced insights for managerial action.

  19. Resilience and Complexity

    DEFF Research Database (Denmark)

    Dahlberg, Rasmus

    2015-01-01

    This paper explores two key concepts: resilience and complexity. The first is understood as an emergent property of the latter, and their inter-relatedness is discussed using a three tier approach. First, by exploring the discourse of each concept, next, by analyzing underlying relationships and,...

  20. Light in complex dielectrics

    NARCIS (Netherlands)

    Schuurmans, F.J.P.

    1999-01-01

    In this thesis the properties of light in complex dielectrics are described, with the two general topics of "modification of spontaneous emission" and "Anderson localization of light". The first part focuses on the spontaneous emission rate of an excited atom in a dielectric host with variable refra

  1. Complex WS 2 nanostructures

    Science.gov (United States)

    Whitby, R. L. D.; Hsu, W. K.; Lee, T. H.; Boothroyd, C. B.; Kroto, H. W.; Walton, D. R. M.

    2002-06-01

    A range of elegant tubular and conical nanostructures has been created by template growth of (WS 2) n layers on the surfaces of single-walled carbon nanotube bundles. The structures exhibit remarkably perfect straight segments together with interesting complexities at the intersections, which are discussed here in detail in order to enhance understanding of the structural features governing tube growth.

  2. Automatic Complexity Analysis

    DEFF Research Database (Denmark)

    Rosendahl, Mads

    1989-01-01

    One way to analyse programs is to to derive expressions for their computational behaviour. A time bound function (or worst-case complexity) gives an upper bound for the computation time as a function of the size of input. We describe a system to derive such time bounds automatically using abstract...

  3. Tevatron's complex collider cousins

    CERN Multimedia

    Fischer, W

    2004-01-01

    Letter referring to Schwarzschild's story "Disappointing performance and tight budgets confront Fermilab with tough decisions" and contesting that the Tevatron is not the most complex accelerator operating. They use the examples of CERN's SPS collider, HERA at DESY and the RHIC at Brookhaven (1/4 page)

  4. The CERN accelerator complex

    CERN Multimedia

    De Melis, Cinzia

    2016-01-01

    The LHC is the last ring (dark blue line) in a complex chain of particle accelerators. The smaller machines are used in a chain to help boost the particles to their final energies and provide beams to a whole set of smaller experiments, which also aim to uncover the mysteries of the Universe.

  5. Transformations, Dynamics and Complexity

    CERN Document Server

    Glazunov, Nikolaj

    2011-01-01

    We review and investigate some new problems and results in the field of dynamical systems generated by iteration of maps, {\\beta}-transformations, partitions, group actions, bundle dynamical systems, Hasse-Kloosterman maps, and some aspects of complexity of the systems.

  6. Symmetry in Complex Networks

    Directory of Open Access Journals (Sweden)

    Angel Garrido

    2011-01-01

    Full Text Available In this paper, we analyze a few interrelated concepts about graphs, such as their degree, entropy, or their symmetry/asymmetry levels. These concepts prove useful in the study of different types of Systems, and particularly, in the analysis of Complex Networks. A System can be defined as any set of components functioning together as a whole. A systemic point of view allows us to isolate a part of the world, and so, we can focus on those aspects that interact more closely than others. Network Science analyzes the interconnections among diverse networks from different domains: physics, engineering, biology, semantics, and so on. Current developments in the quantitative analysis of Complex Networks, based on graph theory, have been rapidly translated to studies of brain network organization. The brain's systems have complex network features—such as the small-world topology, highly connected hubs and modularity. These networks are not random. The topology of many different networks shows striking similarities, such as the scale-free structure, with the degree distribution following a Power Law. How can very different systems have the same underlying topological features? Modeling and characterizing these networks, looking for their governing laws, are the current lines of research. So, we will dedicate this Special Issue paper to show measures of symmetry in Complex Networks, and highlight their close relation with measures of information and entropy.

  7. Electromeric rhodium radical complexes

    NARCIS (Netherlands)

    Puschmann, F.F.; Harmer, J.; Stein, D.; Rüegger, H.; de Bruin, B.; Grützmacher, H.

    2010-01-01

    Radical changes: One single P-Rh-P angle determines whether the odd electron in the paramagnetic complex [Rh(trop2PPh)(PPh3)] is delocalized over the whole molecule (see picture, blue) or is localized on the P—Rh unit (red). The two energetically almost degenerate electromers exist in a fast equilib

  8. Aquaporins in complex tissues

    DEFF Research Database (Denmark)

    Hamann, S; Zeuthen, T; La Cour, M

    1998-01-01

    Multiple physiological fluid movements are involved in vision. Here we define the cellular and subcellular sites of aquaporin (AQP) water transport proteins in human and rat eyes by immunoblotting, high-resolution immunocytochemistry, and immunoelectron microscopy. AQP3 is abundant in bulbar conj......, predicting specific roles for each in the complex network through which water movements occur in the eye....

  9. Complex Interfaces Under Change

    DEFF Research Database (Denmark)

    Rosbjerg, Dan

    and mechanical processes that develop within this structure. Water-related processes at the interfaces between the compartments are complex, depending both on the interface itself, and on the characteristics of the interfaced compartments. Various aspects of global change directly or indirectly impact...

  10. Macroevolution of complex retroviruses

    DEFF Research Database (Denmark)

    Katzourakis, Aris; Gifford, Robert J; Tristem, Michael

    2009-01-01

    Retroviruses can leave a "fossil record" in their hosts' genomes in the form of endogenous retroviruses. Foamy viruses, complex retroviruses that infect mammals, have been notably absent from this record. We have found an endogenous foamy virus within the genomes of sloths and show that foamy...

  11. Complex Digital Visual Systems

    Science.gov (United States)

    Sweeny, Robert W.

    2013-01-01

    This article identifies possibilities for data visualization as art educational research practice. The author presents an analysis of the relationship between works of art and digital visual culture, employing aspects of network analysis drawn from the work of Barabási, Newman, and Watts (2006) and Castells (1994). Describing complex network…

  12. Proteasomes: a complex story

    DEFF Research Database (Denmark)

    Hendil, Klavs B; Hartmann-Petersen, Rasmus

    2004-01-01

    Protein degradation in eukaryotic cells is important for regulation of metabolism, progression through the division cycle, in cell signalling pathways, and in mammals also for generation of antigen fragments for presentation on the major histocompatibility complex (MHC) class I. Most cell proteins...

  13. Energy momentum complex

    Energy Technology Data Exchange (ETDEWEB)

    Nashed, Gamal G.L. [Ain Shams University, Cairo (Egypt). Faculty of Science. Mathematics Dept.

    2010-09-15

    We show that the definition of the energy-momentum complex given by Moeller using Weitzenboeck spacetime in the calculations of gravitational energy gives results which are different from those obtained from other definitions given in the framework of general relativity. (author)

  14. Complex Planar Splines.

    Science.gov (United States)

    1981-05-01

    try todefine a complex planar spline by holomorphic elements like polynomials, then by the well known identity theorem (e.g. Diederich- Remmert [9, p...R. Remmert : Funktionentheorie I, Springer, Berlin, Heidelberg, New York, 1972, 246 p. 10 0. Lehto - K.I. Virtanen: Quasikonforme AbbildunQen, Springer

  15. Procuring complex performance

    DEFF Research Database (Denmark)

    Hartmann, A.; Roehrich, J.; Frederiksen, Lars

    2014-01-01

    Purpose – The paper analyses how public buyers transition from procuring single products and services to procuring complex performance (PCP). The aim is to examine the change in the interactions between buyer and supplier, the emergence of value co-creation and the capability development during t...

  16. The CERN accelerator complex

    CERN Multimedia

    Haffner, Julie

    2013-01-01

    The LHC is the last ring (dark grey line) in a complex chain of particle accelerators. The smaller machines are used in a chain to help boost the particles to their final energies and provide beams to a whole set of smaller experiments, which also aim to uncover the mysteries of the Universe.

  17. Psychopathology and complexity

    Directory of Open Access Journals (Sweden)

    Leonardo Y. Álvarez R

    2010-08-01

    Full Text Available The paradigm of complexity states that reality conveys a chaotic dynamics, ambiguous, blurred, and paradoxical, and that it does not fulfill the values of order, harmony nor perfection. However, such a chaos represents a specific way of organization and order. Human behavior explained by this paradigm vindicates on this way the outstanding role of contradiction and irregularity aside of what is linear and predictable. The purpose of this review has the primary aim to describe some concepts and assumptions that give support to the approach to complexity in behavior, especially concerning the psychopathological behavior of an individual. Some comparisons with concepts associated to complexity in scientific approaches to psychology (contextual and paradigmatical behaviorism and interbehaviorism from its own persepctive are stablished. All these elements are developed underlining the concepts of reciprocal multicausality, complex and hierarchical learning, historical and contextual factors in the comprehension of behavior, and trying to make some extrapolations on the psychopathological behavior. This approach is hence considered appropriate and necessary to understand gnosiological entities and to intervene them in their role of clinical challenges.

  18. Complexity driven photonics

    KAUST Repository

    Fratalocchi, Andrea

    2014-12-01

    Disorder and chaos are ubiquitous phenomena that are mostly unwanted in applications. On the contrary, they can be exploited to create a new technology. In this talk I will summarize my research in this field, discussing chaotic energy harvesting, nonlinear stochastic resonance and complex nanolasers.

  19. Statistical electromagnetics: Complex cavities

    NARCIS (Netherlands)

    Naus, H.W.L.

    2008-01-01

    A selection of the literature on the statistical description of electromagnetic fields and complex cavities is concisely reviewed. Some essential concepts, for example, the application of the central limit theorem and the maximum entropy principle, are scrutinized. Implicit assumptions, biased choic

  20. The Complexity of Metaphor

    Institute of Scientific and Technical Information of China (English)

    贾燕梅

    2007-01-01

    Being as one figurative form of language, metaphor plays the most complicated role to make language colorful and vivid.Demonstrating the types and the features of metaphor, this article will focus on the point that metaphor is a complex language phenomenon heavily loaded with the factor of culture.

  1. Launching Complex Tasks

    Science.gov (United States)

    Jackson, Kara J.; Shahan, Emily C.; Gibbons, Lynsey K.; Cobb, Paul A.

    2012-01-01

    Mathematics lessons can take a variety of formats. In this article, the authors discuss lessons organized around complex mathematical tasks. These lessons usually unfold in three phases. First, the task is introduced to students. Second, students work on solving the task. Third, the teacher "orchestrates" a concluding whole-class discussion in…

  2. The CERN accelerator complex

    CERN Multimedia

    Christiane Lefèvre

    2008-01-01

    The LHC is the last ring (dark grey line) in a complex chain of particle accelerators. The smaller machines are used in a chain to help boost the particles to their final energies and provide beams to a whole set of smaller experiments, which also aim to uncover the mysteries of the Universe.

  3. Debating complexity in modeling

    Science.gov (United States)

    Hunt, Randall J.; Zheng, Chunmiao

    1999-01-01

    Complexity in modeling would seem to be an issue of universal importance throughout the geosciences, perhaps throughout all science, if the debate last year among groundwater modelers is any indication. During the discussion the following questions and observations made up the heart of the debate.

  4. Optical Complex Systems 2008

    Science.gov (United States)

    Brun, Guillaume

    The Optical Complex Systems are more and more in the heart of various systems that industrial applications bring to everyday life. From environment up to spatial applications, OCS is also relevant in monitoring, transportation, robotics, life sciences, sub-marine, and even for agricultural purposes.

  5. COMPLEX PROMOTIONSIN RETAIL

    Directory of Open Access Journals (Sweden)

    O. Yusupova

    2015-10-01

    Full Text Available Complex promotions used by retailers introduce to the consumers several rules that must be satisfied in order to get some benefits and usually refer to multiple products (e.g. “buy two, get one free”. Rules of complex promotions can be quite sophisticated and complicated themselves. Since diversity of complex promotions limited only by marketers’ imagination we can observe broad variety of promotions’ rules and representa¬tions of those rules in retailers’ commercials. Such diversification makes no good for fellow scientist who’s trying to sort all type of promotions into the neatly organized classification. Although we can simple add every single set of rules offered by retailers as a separate form of sales promotion it seems not to be the best way of dealing with such a problem. The better way is to realize that mechanisms underlying that variety of promotions are basically the same, namely changes in demand or quantity demanded. Those two concepts alone provide powerful insight into classification of complex promotions and allow us to comprehend the variety of promotions offered by marketers nowadays.

  6. Geological and geochemical evolution of the Trincheira Complex, a Mesoproterozoic ophiolite in the southwestern Amazon craton, Brazil

    Science.gov (United States)

    Rizzotto, Gilmar José; Hartmann, Léo Afraneo

    2012-09-01

    We document the first-known Mesoproterozoic ophiolite from the southwestern part of the Amazon craton, corresponding to the Trincheira Complex of Calymmian age, and propose a tectonic model that explains many previously enigmatic features of the Precambrian history of this key craton, and discuss its role in the reconstruction of the Columbia supercontinent. The complex comprises extrusive rocks (fine-grained amphibolites derived from massive and pillowed basalts), mafic-ultramafic intrusive rocks, chert, banded iron formation (BIFs), pelites, psammitic and a smaller proportion of calc-silicate rocks. This sequence was deformed, metasomatized and metamorphosed during the development of the Alto Guaporé Belt, a Mesoproterozoic accretionary orogen. The rocks were deformed by a single tectonic event, which included isoclinal folding and metamorphism of the granulite-amphibolite facies. Layered magmatic structures were preserved in areas of low strain, including amygdaloidal and cumulate structures. Metamorphism was pervasive and reached temperatures of 780-853 °C in mafic granulites and 680-720 °C in amphibolites under an overall pressure of 6.8 kbar. The geochemical composition of the extrusive and intrusive rocks indicates that all noncumulus mafic-ultramafic rocks are tholeiitic basalts. The mafic-ultramafic rocks display moderate to strong fractionation of light rare earth elements (LREE), near-flat heavy rare earth element (HREE) patterns and moderate to strong negative high field strength element (HFSE) anomalies (especially Nb), a geochemical signature typical of subduction zones. The lowest units of mafic granulites and porphyroblastic amphibolites in the Trincheira ophiolite are similar to the modern mid-ocean ridge basalt (MORB), although they locally display small Ta, Ti and Nb negative anomalies, indicating a small subduction influence. This behavior changes to an island arc tholeiite (IAT) signature in the upper units of fine-grained amphibolites and

  7. Classification of Software Projects' Complexity

    Science.gov (United States)

    Fitsilis, P.; Kameas, A.; Anthopoulos, L.

    Software project complexity is a subject that has not received detailed attention. The purpose of this chapter is to present a systematic way for studying and modeling software project complexity. The proposed model is based on the widely known and accepted Project Management Body of Knowledge and it uses a typology for modeling complexity based on complexity of faith, fact, and interaction.

  8. Complexity Leadership: A Theoretical Perspective

    Science.gov (United States)

    Baltaci, Ali; Balci, Ali

    2017-01-01

    Complex systems are social networks composed of interactive employees interconnected through collaborative, dynamic ties such as shared goals, perspectives and needs. Complex systems are largely based on "the complex system theory". The complex system theory focuses mainly on finding out and developing strategies and behaviours that…

  9. Reducing GWAS Complexity

    Science.gov (United States)

    Hazelett, Dennis J.; Conti, David V.; Han, Ying; Al Olama, Ali Amin; Easton, Doug; Eeles, Rosalind A.; Kote-Jarai, Zsofia; Haiman, Christopher A.; Coetzee, Gerhard A.

    2016-01-01

    ABSTRACT Genome-wide association studies (GWAS) have revealed numerous genomic 'hits' associated with complex phenotypes. In most cases these hits, along with surrogate genetic variation as measure by numerous single nucleotide polymorphisms (SNPs) that are in linkage disequilibrium, are not in coding genes making assignment of functionality or causality intractable. Here we propose that fine-mapping along with the matching of risk SNPs at chromatin biofeatures lessen this complexity by reducing the number of candidate functional/causal SNPs. For example, we show here that only on average 2 SNPs per prostate cancer risk locus are likely candidates for functionality/causality; we further propose that this manageable number should be taken forward in mechanistic studies. The candidate SNPs can be looked up for each prostate cancer risk region in 2 recent publications in 20151,2 from our groups. PMID:26771711

  10. Polystochastic Models for Complexity

    CERN Document Server

    Iordache, Octavian

    2010-01-01

    This book is devoted to complexity understanding and management, considered as the main source of efficiency and prosperity for the next decades. Divided into six chapters, the book begins with a presentation of basic concepts as complexity, emergence and closure. The second chapter looks to methods and introduces polystochastic models, the wave equation, possibilities and entropy. The third chapter focusing on physical and chemical systems analyzes flow-sheet synthesis, cyclic operations of separation, drug delivery systems and entropy production. Biomimetic systems represent the main objective of the fourth chapter. Case studies refer to bio-inspired calculation methods, to the role of artificial genetic codes, neural networks and neural codes for evolutionary calculus and for evolvable circuits as biomimetic devices. The fifth chapter, taking its inspiration from systems sciences and cognitive sciences looks to engineering design, case base reasoning methods, failure analysis, and multi-agent manufacturing...

  11. Complexes Tickling the $ubject

    Directory of Open Access Journals (Sweden)

    Matthew Gildersleeve

    2016-11-01

    Full Text Available This article continues my earlier work of reading Jung with Lacan. This article will develop Zizek’s work on Lacan’s concept of objet petit a by relating it to a phenomenological interpretation of Jung. I use a number of different examples, including Zizek’s interpretation of Francis Bacon, Edvard Munch, Hans Holbein and Johann Gottlieb Fichte, to describe the objet petit a and its relationship to a phenomenological interpretation of complexes. By integrating other Lacanian concepts, such as subject, drive, fantasy, jouissance, gaze, desire, and ego as well as the imaginary, symbolic and Real, this work also highlights how Hegel and Heidegger can elucidate the relationship between objet petit a and complexes. Jung’s transcendent function and the Rosarium Philosophorum also elucidate the relationship between Jung and Lacan.

  12. Complex Feeding Decisions

    Directory of Open Access Journals (Sweden)

    Anna Miles PhD

    2016-08-01

    Full Text Available Objective: Where swallowing difficulties are chronic or progressive, or a patient is palliative, tube feeding is often not deemed appropriate. Instead, patients continue to eat and drink despite the risks of pneumonia and death. There is currently little evidence to guide clinical practice in this field often termed “risk feeding.” This qualitative study investigated staff, patient, and family member perceptions of risk feeding practices in one New Zealand hospital. Method: Twenty-nine staff members and six patients and/or their family were interviewed. Results: Thematic analysis revealed four global themes: supporting practice, communication, complexity of feeding decisions, and patient and family-centered care. Staff described limited education and organizational policy around risk feeding decisions. Communication was considered a major factor in the success. Conclusion: Feeding decisions are complex in the hospital environment. The themes identified in this study provide a foundation for hospital guideline development and implementation.

  13. Complex Polynomial Vector Fields

    DEFF Research Database (Denmark)

    Dias, Kealey

    The two branches of dynamical systems, continuous and discrete, correspond to the study of differential equations (vector fields) and iteration of mappings respectively. In holomorphic dynamics, the systems studied are restricted to those described by holomorphic (complex analytic) functions...... or meromorphic (allowing poles as singularities) functions. There already exists a well-developed theory for iterative holomorphic dynamical systems, and successful relations found between iteration theory and flows of vector fields have been one of the main motivations for the recent interest in holomorphic...... vector fields. Since the class of complex polynomial vector fields in the plane is natural to consider, it is remarkable that its study has only begun very recently. There are numerous fundamental questions that are still open, both in the general classification of these vector fields, the decomposition...

  14. Stable generalized complex structures

    CERN Document Server

    Cavalcanti, Gil R

    2015-01-01

    A stable generalized complex structure is one that is generically symplectic but degenerates along a real codimension two submanifold, where it defines a generalized Calabi-Yau structure. We introduce a Lie algebroid which allows us to view such structures as symplectic forms. This allows us to construct new examples of stable structures, and also to define period maps for their deformations in which the background three-form flux is either fixed or not, proving the unobstructedness of both deformation problems. We then use the same tools to establish local normal forms for the degeneracy locus and for Lagrangian branes. Applying our normal forms to the four-dimensional case, we prove that any compact stable generalized complex 4-manifold has a symplectic completion, in the sense that it can be modified near its degeneracy locus to produce a compact symplectic 4-manifold.

  15. Sensitivity of Complex Networks

    CERN Document Server

    Angulo, Marco Tulio; Liu, Yang-Yu; Barabási, Albert-László

    2016-01-01

    The sensitivity (i.e. dynamic response) of complex networked systems has not been well understood, making difficult to predict whether new macroscopic dynamic behavior will emerge even if we know exactly how individual nodes behave and how they are coupled. Here we build a framework to quantify the sensitivity of complex networked system of coupled dynamic units. We characterize necessary and sufficient conditions for the emergence of new macroscopic dynamic behavior in the thermodynamic limit. We prove that these conditions are satisfied only for architectures with power-law degree distributions. Surprisingly, we find that highly connected nodes (i.e. hubs) only dominate the sensitivity of the network up to certain critical frequency.

  16. [Complex vascular access].

    Science.gov (United States)

    Mangiarotti, G; Cesano, G; Thea, A; Hamido, D; Pacitti, A; Segoloni, G P

    1998-03-01

    Availability of a proper vascular access is a basic condition for a proper extracorporeal replacement in end-stage chronic renal failure. However, biological factors, management and other problems, may variously condition their middle-long term survival. Therefore, personal experience of over 25 years has been critically reviewed in order to obtain useful information. In particular "hard" situations necessitating complex procedures have been examined but, if possible, preserving the peripherical vascular features.

  17. Complexity of the Ephemeral

    DEFF Research Database (Denmark)

    Ekman, Ulrik

    2015-01-01

    This brief article presents the everyday cultural use of the Snapchat instant messaging application for video chats as an exemplary case of the challenges confronting studies of cinematics in an epoch marked by the rise in network societies of ubiquitous mobile and social media and technics....... It proffers and begins to detail the argument that snap video chats cannot be denigrated as mere ‘shorts’ but must be approached as spatiotemporally and experientally complex....

  18. NDT for Complex Projects

    Science.gov (United States)

    Carnevale, Mario

    2013-04-01

    Non-destructive testing of structures composed of various types of materials is performed using a variety of methods. Most commonly, electromagnetic and acoustic methods are used to perform this task. Advances in computer software and electro-mechanical hardware have resulted in semi-automated systems for performing simple low-cost in-situ concrete testing. These systems are designed to be operated by anyone who can read a manual and push the right buttons. Although useful in many circumstances, we ask: "What happens when concrete structures are not simple and are too complex to be analyzed by these semi-automated systems and, most importantly, by minimally trained operators?" Many infrastructure projects are boldly pushing the limit of traditional engineering design. As structures become more complex, the methods and techniques used to evaluate these structures must also evolve. A first step towards adapting geophysical methods to evaluate complex structures is to develop pre-investigation conceptual models of possible responses that structures will have to available geophysical methods. This approach is important for designing the geometry and data acquisition parameters necessary for achieving the desired results. Examples of case by case assessments of the application of GPR to concrete investigations are examined. These include complex concrete wall structures, soil tunnel structures, and airport runways. HGI's adaption of ground penetrating radar (GPR) and seismic methods for assessing the substrate of a heavily reinforced concrete structure up to seven feet thick is reviewed. A range of GPR antenna frequencies were used to image the concrete and the underlying material. Time and frequency domain GPR analyses where used in the assessment. A multi-channel seismic survey using a roll-along data collection technique was used to assess the resonant frequency of the concrete structure, the nature of the underlying medium, and behavior of the structural system.

  19. The Complex Information Process

    Directory of Open Access Journals (Sweden)

    Edwina Taborsky

    2000-07-01

    Full Text Available Abstract: This paper examines the semiosic development of energy to information within a dyadic reality that operates within the contradictions of both classical and quantum physics. These two realities are examined within the three Peircean modal categories of Firstness, Secondness and Thirdness. The paper concludes that our world cannot operate within either of the two physical realities but instead filiates the two to permit a semiosis or information-generation of complex systems.

  20. The Complex Information Process

    Science.gov (United States)

    Taborsky, Edwina

    2000-09-01

    This paper examines the semiosic development of energy to information within a dyadic reality that operates within the contradictions of both classical and quantum physics. These two realities are examined within the three Peircean modal categories of Firstness, Secondness and Thirdness. The paper concludes that our world cannot operate within either of the two physical realities but instead filiates the two to permit a semiosis or information-generation of complex systems.

  1. COMPLEX QUERY AND METADATA

    OpenAIRE

    Nakatoh, Tetsuya; Omori, Keisuke; Yamada, Yasuhiro; Hirokawa, Sachio

    2003-01-01

    We are developing a search system DAISEn which integrates multiple search engines and generates a metasearch engine automatically. The target search engines of DAISEn are not general search engines, but are search engines specialized in some area. Integration of such engines yields efficiency and quality. There are search engines of new type which accept complex query and return structured data. Integration of such search engines is much harder than that of simple search engines which accept ...

  2. Complex geometries in wood

    DEFF Research Database (Denmark)

    Tamke, Martin; Ramsgaard Thomsen, Mette; Riiber Nielsen, Jacob

    2009-01-01

    The versatility of wood constructions and traditional wood joints for the production of non standard elements was in focus of a design based research. Herein we established a seamless process from digital design to fabrication. A first research phase centered on the development of a robust parame...... parametric model and a generic design language a later explored the possibilities to construct complex shaped geometries with self registering joints on modern wood crafting machines. The research was carried out as collaboration with industrial partners....

  3. Complexity in Dynamical Systems

    Science.gov (United States)

    Moore, Cristopher David

    The study of chaos has shown us that deterministic systems can have a kind of unpredictability, based on a limited knowledge of their initial conditions; after a finite time, the motion appears essentially random. This observation has inspired a general interest in the subject of unpredictability, and more generally, complexity; how can we characterize how "complex" a dynamical system is?. In this thesis, we attempt to answer this question with a paradigm of complexity that comes from computer science, we extract sets of symbol sequences, or languages, from a dynamical system using standard methods of symbolic dynamics; we then ask what kinds of grammars or automata are needed a generate these languages. This places them in the Chomsky heirarchy, which in turn tells us something about how subtle and complex the dynamical system's behavior is. This gives us insight into the question of unpredictability, since these automata can also be thought of as computers attempting to predict the system. In the culmination of the thesis, we find a class of smooth, two-dimensional maps which are equivalent to the highest class in the Chomsky heirarchy, the turning machine; they are capable of universal computation. Therefore, these systems possess a kind of unpredictability qualitatively different from the usual "chaos": even if the initial conditions are known exactly, questions about the system's long-term dynamics are undecidable. No algorithm exists to answer them. Although this kind of unpredictability has been discussed in the context of distributed, many-degree-of -freedom systems (for instance, cellular automata) we believe this is the first example of such phenomena in a smooth, finite-degree-of-freedom system.

  4. Complex and Fractional Dynamics

    Directory of Open Access Journals (Sweden)

    J. A. Tenreiro Machado

    2017-02-01

    Full Text Available Complex systems (CS are pervasive in many areas, namely financial markets; highway transportation; telecommunication networks; world and country economies; social networks; immunological systems; living organisms; computational systems; and electrical and mechanical structures. CS are often composed of a large number of interconnected and interacting entities exhibiting much richer global scale dynamics than could be inferred from the properties and behavior of individual elements. [...

  5. Sporadic meteoroid complex: Modeling

    Science.gov (United States)

    Andreev, V.

    2014-07-01

    The distribution of the sporadic meteoroids flux density over the celestial sphere is the common form of representation of the meteoroids distribution in the vicinity of the Earth's orbit. The determination of the flux density of sporadic meteor bodies is Q(V,e,f) = Q_0 P_e(V) P(e,f) where V is the meteoroid velocity, e,f are the radiant coordinates, Q_0 is the meteoroid flux over whole celestial sphere, P_e(V) is the conditional velocity distributions and P(e,f) is the radiant distribution over the celestial sphere. The sporadic meteoroid complex model is analytical and based on heliocentric velocities and radiant distributions. The multi-mode character of the heliocentric velocity and radiant distributions follows from the analysis of meteor observational data. This fact points to a complicated structure of the sporadic meteoroid complex. It is the consequence of the plurality of the parent bodies and the origin mechanisms of the meteoroids. The meteoroid complex was divided into four groups for that reason and with a goal of more accurate modelling of velocities and radiant distributions. As the classifying parameter to determine the meteoroid membership in any group, we adopt the Tisserand invariant relative to Jupiter T_J = 1/a + 2 A_J^{-3/2} √{a (1 - e^2)} cos i and the meteoroid orbit inclination i. Two meteoroid groups relate to long-period and short-period comets. One meteoroid group is related to asteroids. The relationship to the last, fourth group is a problematic one. Then, we construct models of radiant and velocity distributions for each group. The analytical model for the whole sporadic meteoroid complex is the sum of the ones for each group.

  6. Simplicial Complex Entropy

    OpenAIRE

    2016-01-01

    We propose an entropy function for simplicial complices. Its value gives the expected cost of the optimal encoding of sequences of vertices of the complex, when any two vertices belonging to the same simplex are indistinguishable. We show that the proposed entropy function can be computed efficiently. By computing the entropy of several complices consisting of hundreds of simplices, we show that the proposed entropy function can be used in the analysis of the large sequences of simplicial com...

  7. Drying of complex suspensions

    OpenAIRE

    Xu, Lei; Bergés, Alexis; Lu, Peter J.; Studart, André R.; Schofield, Andrew B.; Oki, Hidekazu; Davies, Simon; Weitz, David A.

    2010-01-01

    We investigate the 3D structure and drying dynamics of complex mixtures of emulsion droplets and colloidal particles, using confocal microscopy. Air invades and rapidly collapses large emulsion droplets, forcing their contents into the surrounding porous particle pack at a rate proportional to the square of the droplet radius. By contrast, small droplets do not collapse, but remain intact and are merely deformed. A simple model coupling the Laplace pressure to Darcy's law correctly estimates ...

  8. Complex biopower installation

    Directory of Open Access Journals (Sweden)

    Tirshu M.

    2008-12-01

    Full Text Available It is presented the technological scheme of complex biopower installation for manufacture of the electric power, hot water and gas at use as raw material of manure, birds dung and firm organic waste products. The suggested technical solution provides practically 100 % use of energy of burnt gas due to the introduced feedback between power station and a bioreactor. Recommendations for the best use of installation in Republics Moldova are developed as well.

  9. [VGKC-complex antibodies].

    Science.gov (United States)

    Watanabe, Osamu

    2013-04-01

    Various antibodies are associated with voltage-gated potassium channels (VGKCs). Representative antibodies to VGKCs were first identified by radioimmunoassays using radioisotope-labeled alpha-dendrotoxin-VGKCs solubilized from rabbit brain. These antibodies were detected only in a proportion of patients with acquired neuromyotonia (Isaacs' syndrome). VGKC antibodies were also detected in patients with Morvan's syndrome and in those with a form of autoimmune limbic encephalitis. Recent studies indicated that the "VGKC" antibodies are mainly directed toward associated proteins (for example LGI-1 and CASPR-2) that complex with the VGKCs themselves. The "VGKC" antibodies are now commonly known as VGKC-complex antibodies. In general, LGI-1 antibodies are most commonly detected in patients with limbic encephalitis with syndrome of inappropriate secretion of antidiuretic hormone. CASPR-2 antibodies are present in the majority of patients with Morvan's syndrome. These patients develop combinations of CNS symptoms, autonomic dysfunction, and peripheral nerve hyperexcitability. Furthermore, VGKC-complex antibodies are tightly associated with chronic idiopathic pain. Hyperexcitability of nociceptive pathways has also been implicated. These antibodies may be detected in sera of some patients with neurodegenerative diseases (for example, amyotrophic lateral sclerosis and Creutzfeldt-Jakob disease).

  10. Control of complex systems

    CERN Document Server

    Albertos, Pedro; Blanke, Mogens; Isidori, Alberto; Schaufelberger, Walter; Sanz, Ricardo

    2001-01-01

    The world of artificial systems is reaching complexity levels that es­ cape human understanding. Surface traffic, electricity distribution, air­ planes, mobile communications, etc. , are examples that demonstrate that we are running into problems that are beyond classical scientific or engi­ neering knowledge. There is an ongoing world-wide effort to understand these systems and develop models that can capture its behavior. The reason for this work is clear, if our lack of understanding deepens, we will lose our capability to control these systems and make they behave as we want. Researchers from many different fields are trying to understand and develop theories for complex man-made systems. This book presents re­ search from the perspective of control and systems theory. The book has grown out of activities in the research program Control of Complex Systems (COSY). The program has been sponsored by the Eu­ ropean Science Foundation (ESF) which for 25 years has been one of the leading players in stimula...

  11. Keynes, Hayek and Complexity

    Science.gov (United States)

    Ormerod, Paul

    In the spirit of the overall topic of the conference, in this paper I consider the extent to which economic theory includes elements of the complex systems approach. I am setting to one side here the developments over the past decade in applying complex systems analysis to economic problems. This is not because this recent work is not important. It most certainly is. But I want to argue that there is a very distinct tradition of what we would now describe as a complex systems approach in the works of two of the greatest economists of the 20th century. There is of course a dominant intellectual paradigm within economics, that known as `neo-classical'economics. This paradigm is by no means an empty box, and is undoubtedly useful in helping to understand how some aspects of the social and economic worlds work. But even in its heyday, neo-classical economics never succeeded by its empirical success in driving out completely other theoretical approaches, for its success was simply not sufficient to do so. Much more importantly, economics over the past twenty or thirty years has become in an increasing state of flux.

  12. Predictive Surface Complexation Modeling

    Energy Technology Data Exchange (ETDEWEB)

    Sverjensky, Dimitri A. [Johns Hopkins Univ., Baltimore, MD (United States). Dept. of Earth and Planetary Sciences

    2016-11-29

    Surface complexation plays an important role in the equilibria and kinetics of processes controlling the compositions of soilwaters and groundwaters, the fate of contaminants in groundwaters, and the subsurface storage of CO2 and nuclear waste. Over the last several decades, many dozens of individual experimental studies have addressed aspects of surface complexation that have contributed to an increased understanding of its role in natural systems. However, there has been no previous attempt to develop a model of surface complexation that can be used to link all the experimental studies in order to place them on a predictive basis. Overall, my research has successfully integrated the results of the work of many experimentalists published over several decades. For the first time in studies of the geochemistry of the mineral-water interface, a practical predictive capability for modeling has become available. The predictive correlations developed in my research now enable extrapolations of experimental studies to provide estimates of surface chemistry for systems not yet studied experimentally and for natural and anthropogenically perturbed systems.

  13. Transition Complexity of Incomplete DFAs

    Directory of Open Access Journals (Sweden)

    Yuan Gao

    2010-08-01

    Full Text Available In this paper, we consider the transition complexity of regular languages based on the incomplete deterministic finite automata. A number of results on Boolean operations have been obtained. It is shown that the transition complexity results for union and complementation are very different from the state complexity results for the same operations. However, for intersection, the transition complexity result is similar to that of state complexity.

  14. Oxytocin microinjected into the central amygdaloid nuclei exerts anti-aggressive effects in male rats

    NARCIS (Netherlands)

    Calcagnoli, Federica; Stubbendorff, Christine; Meyer, Neele; de Boer, Sietse F.; Althaus, Monika; Koolhaas, Jacob

    2015-01-01

    We recently demonstrated that acute and chronic intracerebroventricular enhancement of brain OXT levels induces potent anti-aggressive and pro-social explorative effects during social challenges. However, the exact anatomical location in the brain where OXT exerts its action is still elusive. In the

  15. Connections of the amygdaloid structures integrating olfactory and vomeronasal information in mice

    OpenAIRE

    Cadiz Moretti, Bernardita Josr

    2015-01-01

    La amígdala es considerada una estructura clave en el aprendizaje emocional asociativo en roedores. La mayor parte de los estudios sobre aprendizaje emocional se han centrado en paradigmas de aprendizaje aversivo, cuando al menos, parte de la amígdala es también relevante en el procesamiento de estímulos reforzantes, particularmente estímulos de naturaleza química (olores y feromonas), dado que los roedores son animales macrosmáticos. La amígala es primer relevo telencefalico en donde converg...

  16. Ketogenic diet protects against epileptogenesis as well as neuronal loss in amygdaloid-kindling seizures.

    Science.gov (United States)

    Jiang, Yan; Yang, Yi; Wang, Shuang; Ding, Yao; Guo, Yi; Zhang, Man-Man; Wen, Shu-Qun; Ding, Mei-Ping

    2012-02-01

    Ketogenic diets (KD) have shown beneficial effects in terms of anticonvulsant and anti-epileptogenic properties in several experimental models. However, few studies have investigated the consequences of KD with regards to the anti-epileptogenic and neuroprotective effects in kindling-induced seizures. Here, postnatal day 28 male Sprague-Dawley rats received one of two experimental diets for 4 weeks: (a) a 'classic' 4:1 KD; and (b) a normal regular rodent chow diet (ND). Fully-kindled seizures were achieved by daily electrical stimulation in the amygdala. Seizure stage and after-discharge duration (ADD) were assessed daily. The after-discharge threshold (ADT) was measured every 5 days. The effects of the two diets on neuronal loss were observed before kindling and 20 days after stimulation by Nissl staining. We found that the progression of seizure stage and ADD was delayed by KD. KD prevented the ADT decrease on day 5. The incidence of generalized seizures was lower in the KD group compared to the ND group. The neuronal density was decreased in the ipsilateral hilus of the dentate gyrus (DG) and CA1 area, as well as the contralateral CA1 area before kindling in the KD group. However, KD prevented neuronal loss in the ipsilateral CA1 area 20 days after stimulation. Our data suggest that KD can protect against epileptogenesis by preventing both after-discharge generation and propagation in kindling seizures. In addition, KD also possesses a neuroprotective function during kindling although it changes hippocampal development in early life.

  17. The influence of stress on fear memory processes

    Directory of Open Access Journals (Sweden)

    I.D. Martijena

    2012-04-01

    Full Text Available It is well recognized that stressful experiences promote robust emotional memories, which are well remembered. The amygdaloid complex, principally the basolateral complex (BLA, plays a pivotal role in fear memory and in the modulation of stress-induced emotional responses. A large number of reports have revealed that GABAergic interneurons provide a powerful inhibitory control of the activity of projecting glutamatergic neurons in the BLA. Indeed, a reduced GABAergic control in the BLA is essential for the stress-induced influence on the emergence of associative fear memory and on the generation of long-term potentiation (LTP in BLA neurons. The extracellular signal-regulated kinase (ERK subfamily of the mitogen-activated protein kinase (MAPK signaling pathway in the BLA plays a central role in the consolidation process and synaptic plasticity. In support of the view that stress facilitates long-term fear memory, stressed animals exhibited a phospho-ERK2 (pERK2 increase in the BLA, suggesting the involvement of this mechanism in the promoting influence of threatening stimuli on the consolidation fear memory. Moreover, the occurrence of reactivation-induced lability is prevented when fear memory is encoded under intense stressful conditions since the memory trace remains immune to disruption after recall in previously stressed animals. Thus, the underlying mechanism in retrieval-induced instability seems not to be functional in memories formed under stress. All these findings are indicative that stress influences both the consolidation and reconsolidation fear memory processes. Thus, it seems reasonable to propose that the emotional state generated by an environmental challenge critically modulates the formation and maintenance of long-term fear memory.

  18. Complex-valued autoencoders.

    Science.gov (United States)

    Baldi, Pierre; Lu, Zhiqin

    2012-09-01

    Autoencoders are unsupervised machine learning circuits, with typically one hidden layer, whose learning goal is to minimize an average distortion measure between inputs and outputs. Linear autoencoders correspond to the special case where only linear transformations between visible and hidden variables are used. While linear autoencoders can be defined over any field, only real-valued linear autoencoders have been studied so far. Here we study complex-valued linear autoencoders where the components of the training vectors and adjustable matrices are defined over the complex field with the L(2) norm. We provide simpler and more general proofs that unify the real-valued and complex-valued cases, showing that in both cases the landscape of the error function is invariant under certain groups of transformations. The landscape has no local minima, a family of global minima associated with Principal Component Analysis, and many families of saddle points associated with orthogonal projections onto sub-space spanned by sub-optimal subsets of eigenvectors of the covariance matrix. The theory yields several iterative, convergent, learning algorithms, a clear understanding of the generalization properties of the trained autoencoders, and can equally be applied to the hetero-associative case when external targets are provided. Partial results on deep architecture as well as the differential geometry of autoencoders are also presented. The general framework described here is useful to classify autoencoders and identify general properties that ought to be investigated for each class, illuminating some of the connections between autoencoders, unsupervised learning, clustering, Hebbian learning, and information theory.

  19. Fluorido complexes of technetium

    Energy Technology Data Exchange (ETDEWEB)

    Mariappan Balasekaran, Samundeeswari

    2013-07-04

    Fluorine chemistry has received considerable interest during recent years due to its significant role in the life sciences, especially for drug development. Despite the great nuclear medicinal importance of the radioactive metal technetium in radiopharmaceuticals, its coordination chemistry with the fluorido ligand is by far less explored than that of other ligands. Up to now, only a few technetium fluorides are known. This thesis contains the synthesis, spectroscopic and structural characterization of novel technetium fluorides in the oxidation states ''+1'', ''+2'', ''+4'' and ''+6''. In the oxidation state ''+6'', the fluoridotechnetates were synthesized either from nitridotechnetic(VI) acid or from pertechnetate by using reducing agent and have been isolated as cesium or tetraethylammonium salts. The compounds were characterized spectroscopically and structurally. In the intermediate oxidation state ''+4'', hexafluoridotechnetate(IV) was known for long time and studied spectroscopically. This thesis reports novel and improved syntheses and solved the critical issues of early publications such as the color, some spectroscopic properties and the structure of this key compound. Single crystal analyses of alkali metal, ammonium and tetramethylammonium salts of hexafluoridotechnetate(IV) are presented. In aqueous alkaline solutions, the ammonium salt of hexafluoridotechnetate(IV) undergoes hydrolysis and forms an oxido-bridged dimeric complex. It is the first step hydrolysis product of hexafluoridotechnetate(IV) and was characterized by spectroscopic and crystallographic methods. Low-valent technetium fluorides with the metal in the oxidation states of ''+2'' or ''+1'' are almost unknown. A detailed description of the synthesis and characterization of pentafluoridonitrosyltechnetate(II) is presented. The

  20. Complex Polynomial Vector Fields

    DEFF Research Database (Denmark)

    Dias, Kealey

    vector fields. Since the class of complex polynomial vector fields in the plane is natural to consider, it is remarkable that its study has only begun very recently. There are numerous fundamental questions that are still open, both in the general classification of these vector fields, the decomposition...... or meromorphic (allowing poles as singularities) functions. There already exists a well-developed theory for iterative holomorphic dynamical systems, and successful relations found between iteration theory and flows of vector fields have been one of the main motivations for the recent interest in holomorphic...

  1. Genetics of complex diseases

    DEFF Research Database (Denmark)

    Mellerup, Erling; Møller, Gert Lykke; Koefoed, Pernille

    2012-01-01

    A complex disease with an inheritable component is polygenic, meaning that several different changes in DNA are the genetic basis for the disease. Such a disease may also be genetically heterogeneous, meaning that independent changes in DNA, i.e. various genotypes, can be the genetic basis...... for the disease. Each of these genotypes may be characterized by specific combinations of key genetic changes. It is suggested that even if all key changes are found in genes related to the biology of a certain disease, the number of combinations may be so large that the number of different genotypes may be close...

  2. Complex adaptive systems ecology

    DEFF Research Database (Denmark)

    Sommerlund, Julie

    2003-01-01

    In the following, I will analyze two articles called Complex Adaptive Systems EcologyI & II (Molin & Molin, 1997 & 2000). The CASE-articles are some of the more quirkyarticles that have come out of the Molecular Microbial Ecology Group - a groupwhere I am currently making observational studies....... They are the result of acooperation between Søren Molin, professor in the group, and his brother, JanMolin, professor at Department of Organization and Industrial Sociology atCopenhagen Business School. The cooperation arises from the recognition that bothmicrobial ecology and sociology/organization theory works...

  3. Kinetics of complex plasmas

    CERN Document Server

    Sodha, Mahendra Singh

    2014-01-01

    The presentation in the book is based on charge balance on the dust particles, number and energy balance of the constituents and atom-ion-electron interaction in the gaseous plasma. Size distribution of dust particles, statistical mechanics, Quantum effects in electron emission from and accretion on dust particles and nonlinear interaction of complex plasmas with electric and electromagnetic fields have been discussed in the book. The book introduces the reader to basic concepts and typical applications. The book should be of use to researchers, engineers and graduate students.

  4. Complexity in Managing Modularization

    DEFF Research Database (Denmark)

    Hansen, Poul H. Kyvsgård; Sun, Hongyi

    2011-01-01

    modularization management it is far from clarified. Recognizing the need for further empirical research, we have studied 40 modularity cases in various companies. The studies have been designed as long-term studies leaving time for various types of modularization benefits to emerge. Based on these studies we......In general, the phenomenon of managing modularization is not well known. The cause-effect relationships between modularization and realized benefits are complex and comprehensive. Though a number of research works have contributed to the study of the phenomenon of efficient and effective...

  5. Management of complex fisheries

    DEFF Research Database (Denmark)

    Frost, Hans Staby; Andersen, Peder; Hoff, Ayoe

    2013-01-01

    . This is defined as the management scheme which produces the highest net present value over a 25 year period. The assessed management schemes (scenarios) are composed by several measures as used in the Common Fisheries Policy of the European Union for the cod fishery in the Baltic Sea. The scenarios are total......, including taking into account the response of the fishermen to implemented management measures. To demonstrate the use of complex management models this paper assesses a number of second best management schemes against a first rank optimum (FRO), an ideal individual transferable quotas (ITQ) system...

  6. Complex fermion coherent states

    CERN Document Server

    Tyc, T; Sanders, B C; Oliver, W D; Tyc, Tomas; Hamilton, Brett; Sanders, Barry C.; Oliver, William D.

    2005-01-01

    Whereas boson coherent states provide an elegant, intuitive and useful representation, we show that the desirable features of boson coherent states do not carry over very well to fermion fields unless one is prepared to use exotic approaches such as Grassmann fields. Specifically, we identify four appealing properties of boson coherent states (eigenstate of annihilation operator, displaced vacuum state, preservation of product states under linear coupling, and factorization of correlators) and show that fermion coherent states, and approximations to fermion coherent states, defined over the complex field, do not behave well for any of these four criteria.

  7. Computability, complexity, logic

    CERN Document Server

    Börger, Egon

    1989-01-01

    The theme of this book is formed by a pair of concepts: the concept of formal language as carrier of the precise expression of meaning, facts and problems, and the concept of algorithm or calculus, i.e. a formally operating procedure for the solution of precisely described questions and problems. The book is a unified introduction to the modern theory of these concepts, to the way in which they developed first in mathematical logic and computability theory and later in automata theory, and to the theory of formal languages and complexity theory. Apart from considering the fundamental themes an

  8. Complex and Unpredictable Cardano

    CERN Document Server

    Ekert, Artur

    2008-01-01

    This purely recreational paper is about one of the most colorful characters of the Italian Renaissance, Girolamo Cardano, and the discovery of two basic ingredients of quantum theory, probability and complex numbers. The paper is dedicated to Giuseppe Castagnoli on the occasion of his 65th birthday. Back in the early 1990s, Giuseppe instigated a series of meetings at Villa Gualino, in Torino, which brought together few scattered individuals interested in the physics of computation. By doing so he effectively created and consolidated a vibrant and friendly community of researchers devoted to quantum information science. Many thanks for that!

  9. Characterizing biomaterial complexity

    Directory of Open Access Journals (Sweden)

    L.A. Clifton

    2009-07-01

    Full Text Available Biomaterials research will always require a range of techniques to examine structure and function on a range of length scales and in a range of settings. Neutron scattering provides a unique way of disentangling the molecular and structural complexity of biomaterials through study of the constituent components. We examine how the technique has been used to study surface immobilized proteins and lipid films, floating lipid bilayers as mimics of in vitro planar membranes, and formation of fibres from solution by insects and spiders.

  10. STUDYING COMPLEX ADAPTIVE SYSTEMS

    Institute of Scientific and Technical Information of China (English)

    John H. Holland

    2006-01-01

    Complex adaptive systems (cas) - systems that involve many components that adapt or learn as they interact - are at the heart of important contemporary problems. The study of cas poses unique challenges: Some of our most powerful mathematical tools, particularly methods involving fixed points, attractors, and the like, are of limited help in understanding the development of cas. This paper suggests ways to modify research methods and tools, with an emphasis on the role of computer-based models, to increase our understanding of cas.

  11. Polyhydride complexes for hydrogen storage

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, C.M. [Univ. of Hawaii, Honolulu, HI (United States)

    1995-09-01

    Polyhydride metal complexes are being developed for application in hydrogen storage. Efforts have focused on developing complexes with improved available hydrogen weight percentages. We have explored the possibility that complexes containing aromatic hydrocarbon ligands could store hydrogen at both the metal center and in the ligands. We have synthesized novel indenyl hydride complexes and explored their reactivity with hydrogen. The reversible hydrogenation of [IrH{sub 3}(PPh{sub 3})({eta}{sup 5}-C{sub 10}H{sub 7})]{sup +} has been achieved. While attempting to prepare {eta}{sup 6}-tetrahydronaphthalene complexes, we discovered that certain polyhydride complexes catalyze both the hydrogenation and dehydrogenation of tetrahydronaphthalene.

  12. Canonical metrics on complex manifold

    Institute of Scientific and Technical Information of China (English)

    YAU Shing-Tung

    2008-01-01

    @@ Complex manifolds are topological spaces that are covered by coordinate charts where the Coordinate changes are given by holomorphic transformations. For example, Riemann surfaces are one dimensional complex manifolds. In order to understand complex manifolds, it is useful to introduce metrics that are compatible with the complex structure. In general, we should have a pair (M, ds2M) where ds2M is the metric. The metric is said to be canonical if any biholomorphisms of the complex manifolds are automatically isometries. Such metrics can naturally be used to describe invariants of the complex structures of the manifold.

  13. Canonical metrics on complex manifold

    Institute of Scientific and Technical Information of China (English)

    YAU; Shing-Tung(Yau; S.-T.)

    2008-01-01

    Complex manifolds are topological spaces that are covered by coordinate charts where the coordinate changes are given by holomorphic transformations.For example,Riemann surfaces are one dimensional complex manifolds.In order to understand complex manifolds,it is useful to introduce metrics that are compatible with the complex structure.In general,we should have a pair(M,ds~2_M)where ds~2_M is the metric.The metric is said to be canonical if any biholomorphisms of the complex manifolds are automatically isometries.Such metrics can naturally be used to describe invariants of the complex structures of the manifold.

  14. Shapes of interacting RNA complexes

    DEFF Research Database (Denmark)

    Fu, Benjamin Mingming; Reidys, Christian

    2014-01-01

    Shapes of interacting RNA complexes are studied using a filtration via their topological genus. A shape of an RNA complex is obtained by (iteratively) collapsing stacks and eliminating hairpin loops.This shape-projection preserves the topological core of the RNA complex and for fixed topological...... genus there are only finitely many such shapes. Our main result is a new bijection that relates the shapes of RNA complexes with shapes of RNA structures. This allows to compute the shape polynomial of RNA complexes via the shape polynomial of RNA structures. We furthermore present a linear time uniform...... sampling algorithm for shapes of RNA complexes of fixed topological genus....

  15. Theoretical research progress in complexity of complex dynamical networks

    Institute of Scientific and Technical Information of China (English)

    Fang Jinqing

    2007-01-01

    This article reviews the main progress in dynamical complexity of theoretical models for nonlinear complex networks proposed by our Joint Complex Network Research Group (JCNRG). The topological and dynamical properties of these theoretical models are numerically and analytically studied. Several findings are useful for understanding and deeply studying complex networks from macroscopic to microscopic levels and have a potential of applications in real-world networks.

  16. Complex dynamical invariants for two-dimensional complex potentials

    Indian Academy of Sciences (India)

    J S Virdi; F Chand; C N Kumar; S C Mishra

    2012-08-01

    Complex dynamical invariants are searched out for two-dimensional complex potentials using rationalization method within the framework of an extended complex phase space characterized by $x = x_{1} + ip_{3}. y = x_{2} + ip_{4}, p_{x} = p_{1} + ix_{3}, p_{y} = p_{2} + ix_{4}$. It is found that the cubic oscillator and shifted harmonic oscillator admit quadratic complex invariants. THe obtained invariants may be useful for studying non-Hermitian Hamiltonian systems.

  17. The authority of complexity.

    Science.gov (United States)

    Stehr, N; Grundmann, R

    2001-06-01

    The assertion about the unique 'complexity' or the peculiarly intricate character of social phenomena has, at least within sociology, a long, venerable and virtually uncontested tradition. At the turn of the last century, classical social theorists, for example, Georg Simmel and Emile Durkheim, made prominent and repeated reference to this attribute of the subject matter of sociology and the degree to which it complicates, even inhibits the develop and application of social scientific knowledge. Our paper explores the origins, the basis and the consequences of this assertion and asks in particular whether the classic complexity assertion still deserves to be invoked in analyses that ask about the production and the utilization of social scientific knowledge in modern society. We present John Maynard Keynes' economic theory and its practical applications as an illustration. We conclude that the practical value of social scientific knowledge is not dependent on a faithful, in the sense of complete, representation of social reality. Instead, social scientific knowledge that wants to optimize its practicality has to attend and attach itself to elements of social situations that can be altered or are actionable.

  18. Tuberous sclerosis complex.

    Science.gov (United States)

    Henske, Elizabeth P; Jóźwiak, Sergiusz; Kingswood, J Christopher; Sampson, Julian R; Thiele, Elizabeth A

    2016-05-26

    Tuberous sclerosis complex (TSC) is an autosomal dominant disorder that affects multiple organ systems and is caused by loss-of-function mutations in one of two genes: TSC1 or TSC2. The disorder can affect both adults and children. First described in depth by Bourneville in 1880, it is now estimated that nearly 2 million people are affected by the disease worldwide. The clinical features of TSC are distinctive and can vary widely between individuals, even within one family. Major features of the disease include tumours of the brain, skin, heart, lungs and kidneys, seizures and TSC-associated neuropsychiatric disorders, which can include autism spectrum disorder and cognitive disability. TSC1 (also known as hamartin) and TSC2 (also known as tuberin) form the TSC protein complex that acts as an inhibitor of the mechanistic target of rapamycin (mTOR) signalling pathway, which in turn plays a pivotal part in regulating cell growth, proliferation, autophagy and protein and lipid synthesis. Remarkable progress in basic and translational research, in addition to several randomized controlled trials worldwide, has led to regulatory approval of the use of mTOR inhibitors for the treatment of renal angiomyolipomas, brain subependymal giant cell astrocytomas and pulmonary lymphangioleiomyomatosis, but further research is needed to establish full indications of therapeutic treatment. In this Primer, we review the state-of-the-art knowledge in the TSC field, including the molecular and cellular basis of the disease, medical management, major knowledge gaps and ongoing research towards a cure.

  19. Organometallic Complexes of Graphene

    CERN Document Server

    Sarkar, Santanu; Bekyarova, Elena; Haddon, Robert C

    2013-01-01

    We demonstrate the organometallic hexahapto complexation of chromium with graphene, graphite and carbon nanotubes. All of these extended periodic pi-electron systems exhibit some degree of reactivity toward the reagents CrCO)6 and (eta6-benzene)Cr(CO)3, and we are able to demonstrate the formation of (eta6-rene)Cr(CO)3 or (eta6-arene)2Cr, where arene = single-walled carbon nanotubes (SWNT), exfoliated graphene (XG), epitaxial graphene (EG) and highly-oriented pyrolytic graphite (HOPG). We find that the SWNTs are the least reactive presumably as a result of the effect of curvature on the formation of the hexahapto bond; in the case of HOPG, (eta6-HOPG)Cr(CO)3 was isolated while the exfoliated graphene samples were found to give both (eta6-graphene)2Cr, and (eta6-graphene)Cr(CO)3 structures. We report simple and efficient routes for the mild decomplexation of the graphene-chromium complexes which appears to restore the original pristine graphene state. This study represents the first example of the use of graph...

  20. The Orpheus complex.

    Science.gov (United States)

    Dawson, T

    2000-04-01

    This paper examines the possible psychological implications of two adaptations of the myth of Orpheus and Eurydice, both of which were completed in 1997. The first is by a man: 'Deconstructing Harry', a film by Woody Allen. The second is by a woman: 'Eurydice in the Underworld', a short story written by Kathy Acker in the last year of her life. The paper argues that there are only four 'necessary events' in the myth of Orpheus and Eurydice. It defines the sequence of these events as a 'mythic pattern' that represents the experience of loss, unconscious yearning, depression, and psychological inflation. The film is examined as an expression of an 'Orpheus complex', the short story as an expression of an 'Eurydice complex'. The paper suggests a possible reason for the persistence of interest in the myth throughout the twentieth century. Although it notes that women appear to find it easier to free themselves from identification with the mythic pattern, it also provides reasons for thinking that men may be about to do the same.

  1. Complex Semantic Networks

    Science.gov (United States)

    Teixeira, G. M.; Aguiar, M. S. F.; Carvalho, C. F.; Dantas, D. R.; Cunha, M. V.; Morais, J. H. M.; Pereira, H. B. B.; Miranda, J. G. V.

    Verbal language is a dynamic mental process. Ideas emerge by means of the selection of words from subjective and individual characteristics throughout the oral discourse. The goal of this work is to characterize the complex network of word associations that emerge from an oral discourse from a discourse topic. Because of that, concepts of associative incidence and fidelity have been elaborated and represented the probability of occurrence of pairs of words in the same sentence in the whole oral discourse. Semantic network of words associations were constructed, where the words are represented as nodes and the edges are created when the incidence-fidelity index between pairs of words exceeds a numerical limit (0.001). Twelve oral discourses were studied. The networks generated from these oral discourses present a typical behavior of complex networks and their indices were calculated and their topologies characterized. The indices of these networks obtained from each incidence-fidelity limit exhibit a critical value in which the semantic network has maximum conceptual information and minimum residual associations. Semantic networks generated by this incidence-fidelity limit depict a pattern of hierarchical classes that represent the different contexts used in the oral discourse.

  2. Complexity in language acquisition.

    Science.gov (United States)

    Clark, Alexander; Lappin, Shalom

    2013-01-01

    Learning theory has frequently been applied to language acquisition, but discussion has largely focused on information theoretic problems-in particular on the absence of direct negative evidence. Such arguments typically neglect the probabilistic nature of cognition and learning in general. We argue first that these arguments, and analyses based on them, suffer from a major flaw: they systematically conflate the hypothesis class and the learnable concept class. As a result, they do not allow one to draw significant conclusions about the learner. Second, we claim that the real problem for language learning is the computational complexity of constructing a hypothesis from input data. Studying this problem allows for a more direct approach to the object of study--the language acquisition device-rather than the learnable class of languages, which is epiphenomenal and possibly hard to characterize. The learnability results informed by complexity studies are much more insightful. They strongly suggest that target grammars need to be objective, in the sense that the primitive elements of these grammars are based on objectively definable properties of the language itself. These considerations support the view that language acquisition proceeds primarily through data-driven learning of some form.

  3. From Complex Fractional Fourier Transform to Complex Fractional Radon Transform

    Institute of Scientific and Technical Information of China (English)

    FAN Hong-Yi; JIANG Nian-Quan

    2004-01-01

    We show that for n-dimensional complex fractional Fourier transform the corresponding complex fractional Radon transform can also be derived, however, it is different from the direct product of two n-dimensional real fractional Radon transforms. The complex fractional Radon transform of two-mode Wigner operator is calculated.

  4. Not so Complex: Iteration in the Complex Plane

    Science.gov (United States)

    O'Dell, Robin S.

    2014-01-01

    The simple process of iteration can produce complex and beautiful figures. In this article, Robin O'Dell presents a set of tasks requiring students to use the geometric interpretation of complex number multiplication to construct linear iteration rules. When the outputs are plotted in the complex plane, the graphs trace pleasing designs…

  5. Effect of gabapentin on anxiety-like behaviors induced by neuropathic pain and NR2B expression in basolateral nucleus of the amygdala of rats%加巴喷丁对神经病理性疼痛大鼠焦虑样行为和杏仁体基底外侧核NR2B表达的影响

    Institute of Scientific and Technical Information of China (English)

    尹玉洁; 于剑锋

    2015-01-01

    目的 观察加巴喷丁对神经病理性疼痛(neuropathic pain,NP)诱发的大鼠焦虑样行为和杏仁体基底外侧核(basolateral nucleus of the amygdale,BLA) N-甲基-D-天门冬氨酸(N-Methyl-D-Aspartate,NMDA)受体2B亚基(NR2B)表达的影响.方法 选择30只健康的3月龄雄性Wistar大鼠,体重250~280 g,随机均分为假手术组(S组)、神经病理性疼痛模型组(NP组)、加巴喷丁组(G组).神经病理性疼痛模型采用右侧坐骨神经慢性压迫损伤(chronic constriction injury,CCI)的方法制备.G组于CCI后3d开始腹腔注射加巴喷丁100 mg/kg,每天一次.分别于术后3、7、10和14 d测右侧后爪机械缩足阈值(mechanical withdrawal threshold,MWT)和热缩足潜伏期(thermal with-drawal latency,TWL).术后第14天,通过高架十字迷宫测试神经病理性疼痛对大鼠情绪的影响,计算开放臂进入次数百分比和开放臂停留时间百分比,然后取大鼠BLA组织用RT-PCR、Western blot和免疫荧光方法检测NR2B mRNA和蛋白表达.结果 与术前1d比较,术后各时点NP组MWT明显减少、TWL明显缩短(P<0.05),而术后3dG组MWT明显减少、TWL明显缩短(P<0.05).与NP组比较,术后7、10和14dG组MWT明显增加、TWL明显延长(P<0.05),术后第14天S组和G组的开放臂进入次数百分比和开放臂停留时间百分比明显升高(P<0.05),术后第14天BLA区S组和G组NR2B mRNA相对吸光度明显减少、NR2B蛋白表达明显降低(P<0.05),而S组和G组平均相对荧光密度值明显下降(P<0.05).结论 加巴喷丁具有治疗神经病理性疼痛作用可反转其导致的焦虑样反应并使杏仁体的NR2B表达下调.

  6. Amphotericin B Lipid Complex Injection

    Science.gov (United States)

    Amphotericin B lipid complex injection is used to treat serious, possibly life-threatening fungal infections in people who did not respond ... to tolerate conventional amphotericin B therapy. Amphotericin B lipid complex injection is in a class of medications ...

  7. Recent Advances in Complex Networks

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Dramatic advances in the field of complex networks have been witnessed in the past few years. This paper reviews some important results in this direction of rapidly evolving research, with emphasis on the relationship between the dynamics and the topology of complex networks. Basic quantities and typical examples of various complex networks are described. Robustness of connectivity and epidemic dynamics in complex networks are evaluated.

  8. Geometric Complexity Theory: Introduction

    CERN Document Server

    Sohoni, Ketan D Mulmuley Milind

    2007-01-01

    These are lectures notes for the introductory graduate courses on geometric complexity theory (GCT) in the computer science department, the university of Chicago. Part I consists of the lecture notes for the course given by the first author in the spring quarter, 2007. It gives introduction to the basic structure of GCT. Part II consists of the lecture notes for the course given by the second author in the spring quarter, 2003. It gives introduction to invariant theory with a view towards GCT. No background in algebraic geometry or representation theory is assumed. These lecture notes in conjunction with the article \\cite{GCTflip1}, which describes in detail the basic plan of GCT based on the principle called the flip, should provide a high level picture of GCT assuming familiarity with only basic notions of algebra, such as groups, rings, fields etc.

  9. Deformable Simplicial Complexes

    DEFF Research Database (Denmark)

    Misztal, Marek Krzysztof

    In this dissertation we present a novel method for deformable interface tracking in 2D and 3D|deformable simplicial complexes (DSC). Deformable interfaces are used in several applications, such as fluid simulation, image analysis, reconstruction or structural optimization. In the DSC method......, the interface (curve in 2D; surface in 3D) is represented explicitly as a piecewise linear curve or surface. However, the domain is also subject to discretization: triangulation in 2D; tetrahedralization in 3D. This way, the interface can be alternatively represented as a set of edges/triangles separating...... demonstrate those strengths in several applications. In particular, a novel, DSC-based fluid dynamics solver has been developed during the PhD project. A special feature of this solver is that due to the fact that DSC maintains an explicit interface representation, surface tension is more easily dealt with...

  10. Complex Hamiltonian Dynamics

    CERN Document Server

    Bountis, Tassos

    2012-01-01

    This book introduces and explores modern developments in the well established field of Hamiltonian dynamical systems. It focuses on high degree-of-freedom systems and the transitional regimes between regular and chaotic motion. The role of nonlinear normal modes is highlighted and the importance of low-dimensional tori in the resolution of the famous FPU paradox is emphasized. Novel powerful numerical methods are used to study localization phenomena and distinguish order from strongly and weakly chaotic regimes. The emerging hierarchy of complex structures in such regimes gives rise to particularly long-lived patterns and phenomena called quasi-stationary states, which are explored in particular in the concrete setting of one-dimensional Hamiltonian lattices and physical applications in condensed matter systems.  The self-contained and pedagogical approach is blended with a unique balance between mathematical rigor, physics insights and concrete applications. End of chapter exercises and (more demanding) res...

  11. Simplifying Complex Problems

    Directory of Open Access Journals (Sweden)

    Dan Ophir

    2011-12-01

    Full Text Available The process of making complex and controversial decisions, that is, dealing with moral or ethical dilemmas, have intrigued people and inspired writers from time immemorial. Dilemmas give both color and depth to characters in good literary works. But beyond literary fiction, dilemmas occupy society in every day issues such as in introducing legislation or solving current political problems. One example of a current political dilemma is how to deal with Iran’s quest for nuclear weapons. If it were possible to assess and quantify each of the alternative solutions for a given problem, the process of decision making would be much easier. If a problem involves only two optional solutions, game theory techniques can be used. However, real life problems are usually multi-unit, multi-optional problems, as in Iran

  12. Random geometric complexes

    CERN Document Server

    Kahle, Matthew

    2009-01-01

    We study the expected topological properties of Cech and Vietoris-Rips complexes built on randomly sampled points in R^d. These are, in some cases, analogues of known results for connectivity and component counts for random geometric graphs. However, an important difference in this setting is that homology is not monotone in the underlying parameter. In the sparse range, we compute the expectation and variance of the Betti numbers, and establish Central Limit Theorems and concentration of measure. In the dense range, we introduce Morse theoretic arguments to bound the expectation of the Betti numbers, which is the main technical contribution of this article. These results provide a detailed probabilistic picture to compare with the topological statistics of point cloud data.

  13. Segmentation of complex document

    Directory of Open Access Journals (Sweden)

    Souad Oudjemia

    2014-06-01

    Full Text Available In this paper we present a method for segmentation of documents image with complex structure. This technique based on GLCM (Grey Level Co-occurrence Matrix used to segment this type of document in three regions namely, 'graphics', 'background' and 'text'. Very briefly, this method is to divide the document image, in block size chosen after a series of tests and then applying the co-occurrence matrix to each block in order to extract five textural parameters which are energy, entropy, the sum entropy, difference entropy and standard deviation. These parameters are then used to classify the image into three regions using the k-means algorithm; the last step of segmentation is obtained by grouping connected pixels. Two performance measurements are performed for both graphics and text zones; we have obtained a classification rate of 98.3% and a Misclassification rate of 1.79%.

  14. Turbulence in complex terrain

    Energy Technology Data Exchange (ETDEWEB)

    Mann, Jakob [Risoe National Lab., Wind Energy and Atmosheric Physics Dept., Roskilde (Denmark)

    1999-03-01

    The purpose of this work is to develop a model of the spectral velocity-tensor in neutral flow over complex terrain. The resulting equations are implemented in a computer code using the mean flow generated by a linear mean flow model as input. It estimates turbulence structure over hills (except on the lee side if recirculation is present) in the so-called outer layer and also models the changes in turbulence statistics in the vicinity roughness changes. The generated turbulence fields are suitable as input for dynamic load calculations on wind turbines and other tall structures and is under implementation in the collection of programs called WA{sup s}P Engineering. (au) EFP-97; EU-JOULE-3. 15 refs.

  15. Complex pendulum biomass sensor

    Science.gov (United States)

    Hoskinson, Reed L.; Kenney, Kevin L.; Perrenoud, Ben C.

    2007-12-25

    A complex pendulum system biomass sensor having a plurality of pendulums. The plurality of pendulums allow the system to detect a biomass height and density. Each pendulum has an angular deflection sensor and a deflector at a unique height. The pendulums are passed through the biomass and readings from the angular deflection sensors are fed into a control system. The control system determines whether adjustment of machine settings is appropriate and either displays an output to the operator, or adjusts automatically adjusts the machine settings, such as the speed, at which the pendulums are passed through the biomass. In an alternate embodiment, an entanglement sensor is also passed through the biomass to determine the amount of biomass entanglement. This measure of entanglement is also fed into the control system.

  16. Invitation to complex analysis

    CERN Document Server

    Boas, Ralph P

    2010-01-01

    Ideal for a first course in complex analysis, this book can be used either as a classroom text or for independent study. Written at a level accessible to advanced undergraduates and beginning graduate students, the book is suitable for readers acquainted with advanced calculus or introductory real analysis. The treatment goes beyond the standard material of power series, Cauchy's theorem, residues, conformal mapping, and harmonic functions by including accessible discussions of intriguing topics that are uncommon in a book at this level. The flexibility afforded by the supplementary topics and applications makes the book adaptable either to a short, one-term course or to a comprehensive, full-year course. Detailed solutions of the exercises both serve as models for students and facilitate independent study. Supplementary exercises, not solved in the book, provide an additional teaching tool. This second edition has been painstakingly revised by the author's son, himself an award-winning mathematical expositor...

  17. Random complex fewnomials, I

    CERN Document Server

    Shiffman, Bernard

    2010-01-01

    We introduce several notions of `random fewnomials', i.e. random polynomials with a fixed number f of monomials of degree N. The f exponents are chosen at random and then the coefficients are chosen to be Gaussian random, mainly from the SU(m + 1) ensemble. The results give limiting formulas as N goes to infinity for the expected distribution of complex zeros of a system of k random fewnomials in m variables. When k = m, for SU(m + 1) polynomials, the limit is the Monge-Ampere measure of a toric Kaehler potential on CP^m obtained by averaging a `discrete Legendre transform' of the Fubini-Study symplectic potential at f points of the unit simplex in R^m.

  18. Complex performance in construction

    DEFF Research Database (Denmark)

    Bougrain, Frédéric; Forman, Marianne; Gottlieb, Stefan Christoffer

    To fulfil the expectations of demanding clients, new project-delivery mechanisms have been developed. Approaches focusing on performance-based building or new procurement processers such as new forms of private-public partnerships are considered as solutions improving the overall performance...... of the industry. The main objective of this project was to understand how the development of integrated solutions in construction led to distinct configuration of actors and structures. Furthermore, the project analyses whether these changes modified project processes and contributed to the delivery of new value...... to the end users. This report summarises the results from work undertaken in the international collaborative project “Procuring and Operating Complex Products and Systems in Construction” (POCOPSC). POCOPSC was carried out in the period 2010-2014. The project was executed in collaboration between CSTB...

  19. Complex Maxwell's equations

    Institute of Scientific and Technical Information of China (English)

    A.I.Arbab

    2013-01-01

    A unified complex model of Maxwell's equations is presented.The wave nature of the electromagnetic field vector is related to the temporal and spatial distributions and the circulation of charge and current densities.A new vacuum solution is obtained,and a new transformation under which Maxwell's equations are invariant is proposed.This transformation extends ordinary gauge transformation to include charge-current as well as scalar-vector potential.An electric dipole moment is found to be related to the magnetic charges,and Dirac's quantization is found to determine an uncertainty relation expressing the indeterminacy of electric and magnetic charges.We generalize Maxwell's equations to include longitudinal waves.A formal analogy between this formulation and Dirac's equation is also discussed.

  20. Complex dynamics in nanosystems.

    Science.gov (United States)

    Ni, Xuan; Ying, Lei; Lai, Ying-Cheng; Do, Younghae; Grebogi, Celso

    2013-05-01

    Complex dynamics associated with multistability have been studied extensively in the past but mostly for low-dimensional nonlinear dynamical systems. A question of fundamental interest is whether multistability can arise in high-dimensional physical systems. Motivated by the ever increasing widespread use of nanoscale systems, we investigate a prototypical class of nanoelectromechanical systems: electrostatically driven Si nanowires, mathematically described by a set of driven, nonlinear partial differential equations. We develop a computationally efficient algorithm to solve the equations. Our finding is that multistability and complicated structures of basins of attraction are common types of dynamics, and the latter can be attributed to extensive transient chaos. Implications of these phenomena to device operations are discussed.

  1. Complexity Science for Simpletons

    Directory of Open Access Journals (Sweden)

    Feinstein C. A.

    2006-07-01

    Full Text Available In this article, we shall describe some of the most interesting topics in the subject of Complexity Science for a general audience. Anyone with a solid foundation in high school mathematics (with some calculus and an elementary understanding of computer programming will be able to follow this article. First, we shall explain the significance of the P versus NP problem and solve it. Next, we shall describe two other famous mathematics problems, the Collatz 3n+ 1 Conjecture and the Riemann Hypothesis, and show how both Chaitin’s incompleteness theorem and Wolfram’s notion of “computational irreducibility” are important for understanding why no one has, as of yet, solved these two problems.

  2. Thermodynamics of complexity

    DEFF Research Database (Denmark)

    Westerhoff, Hans V.; Jensen, Peter Ruhdal; Snoep, Jacky L.

    1998-01-01

    Thermodynamics has always been a remarkable science in that it studies macroscopic properties that are only partially determined by the properties of individual molecules. Entropy and free energy only exist in constellations of more than a single molecule (degree of freedom). They are the so...... understanding of this BioComplexity, modem thermodynamic concepts and methods (nonequilibrium thermodynamics, metabolic and hierarchical control analysis) will be needed. We shall propose to redefine nonequilibrium thermodynamics as: The science that aims at understanding the behaviour of nonequilibrium systems...... by taking into account both the molecular properties and the emergent properties that are due to (dys)organisation. This redefinition will free nonequilibrium thermodynamics from the limitations imposed by earlier near-equilibrium assumptions, resolve the duality with kinetics, and bridge the apparent gap...

  3. Complex wounds Feridas complexas

    Directory of Open Access Journals (Sweden)

    Marcus Castro Ferreira

    2006-01-01

    Full Text Available Complex wound is the term used more recently to group those well-known difficult wounds, either chronic or acute, that challenge medical and nursing teams. They defy cure using conventional and simple "dressings" therapy and currently have a major socioeconomic impact. The purpose of this review is to bring these wounds to the attention of the health-care community, suggesting that they should be treated by multidisciplinary teams in specialized hospital centers. In most cases, surgical treatment is unavoidable, because the extent of skin and subcutaneous tissue loss requires reconstruction with grafts and flaps. New technologies, such as the negative pressure device, should be introduced. A brief review is provided of the major groups of complex wounds-diabetic wounds, pressure sores, chronic venous ulcers, post-infection soft-tissue gangrenes, and ulcers resulting from vasculitis.Ferida complexa é uma nova definição para identificar aquelas feridas crônicas e algumas agudas já bem conhecidas e que desafiam equipes médicas e de enfermagem. São difíceis de serem resolvidas usando tratamentos convencionais e simples curativos. Têm atualmente grande impacto sócio-econômico. Esta revisão procura atrair atenção da comunidade de profissionais de saúde para estas feridas, sugerindo que devam ser tratadas por equipe multidisciplinar em centro hospitalar especializado. Na maioria dos casos o tratamento cirúrgico deve ser indicado, uma vez que a perda de pele e tecido subcutâneo é extensa, necessitando de reconstrução com enxertos e retalhos. Nova tecnologia, como uso da terapia por pressão negativa foi introduzido. Breves comentários sobre os principais grupos de feridas complexas: pé diabético, úlceras por pressão, úlceras venosas, síndrome de Fournier e vasculites.

  4. Kolmogorov complexity as a language

    CERN Document Server

    Shen, Alexander

    2011-01-01

    The notion of Kolmogorov complexity (=the minimal length of a program that generates some object) is often useful as a kind of language that allows us to reformulate some notions and therefore provide new intuition. In this survey we provide (with minimal comments) many different examples where notions and statements that involve Kolmogorov complexity are compared with their counterparts not involving complexity.

  5. Managing complexity of aerospace systems

    Science.gov (United States)

    Tamaskar, Shashank

    Growing complexity of modern aerospace systems has exposed the limits of conventional systems engineering tools and challenged our ability to design them in a timely and cost effective manner. According to the US Government Accountability Office (GAO), in 2009 nearly half of the defense acquisition programs are expecting 25% or more increase in unit acquisition cost. Increase in technical complexity has been identified as one of the primary drivers behind cost-schedule overruns. Thus to assure the affordability of future aerospace systems, it is increasingly important to develop tools and capabilities for managing their complexity. We propose an approach for managing the complexity of aerospace systems to address this pertinent problem. To this end, we develop a measure that improves upon the state-of-the-art metrics and incorporates key aspects of system complexity. We address the problem of system decomposition by presenting an algorithm for module identification that generates modules to minimize integration complexity. We demonstrate the framework on diverse spacecraft and show the impact of design decisions on integration cost. The measure and the algorithm together help the designer track and manage complexity in different phases of system design. We next investigate how complexity can be used as a decision metric in the model-based design (MBD) paradigm. We propose a framework for complexity enabled design space exploration that introduces the idea of using complexity as a non-traditional design objective. We also incorporate complexity with the component based design paradigm (a sub-field of MBD) and demonstrate it on several case studies. The approach for managing complexity is a small but significant contribution to the vast field of complexity management. We envision our approach being used in concert with a suite of complexity metrics to provide an ability to measure and track complexity through different stages of design and development. This will not

  6. Effect of Protein Malnutrition on Efferent Projections of Amygdala to the Hippocampus

    Directory of Open Access Journals (Sweden)

    Gholamreza Hassanzadeh

    2010-11-01

    Full Text Available ABSTRACTIntroduction: Previous investigations have shown that protein malnutrition can alters the structure and function of some areas of hippocampal formation. We investigated the effect of protein malnutrition on amygdaloid projections to the CA1 hippocampal area. In this study we investigated level and pattern of distribution of efferent projections from amygdala to hippocampus in the rat by Horseradish Peroxidas (HRP neural tract tracing in 2 groups; Control group fed with regular diet (% 18 proteinsand case group fed with low protein diet (%8. We used SPSS 11.0 (T test & mann-withney Software for data analysis.Methods: Following injection of HRP to CA1 region of hippocampus in the control group Rats, Labelled neurons showed more density in the Basolateral, Cortical and Medial nuclear Groups. Having done the analysis and examining the relations between the case data and those of the control groups, we found that number of labelled neurons in the Basolateral, Cortical & medial nuclei were decreased in the case group(p<0.05. Our findings showed that different nuclei of amygdala (Basolateral, Cortical and Medial send projections to CA1 region of hippocampus; Among, them basolateral nuclei group send the most projections . Discussion: This results may be caused by decrease of activity of neural cells after protein malnutrition, that can results in impairment in growth and development of nervous system. Also it is possible that axoplasmic transfer rate maybe decreased in this condition.

  7. Complexity, Information and Biological Organisation

    Directory of Open Access Journals (Sweden)

    Attila Grandpierre

    2005-12-01

    Full Text Available Regarding the widespread confusion about the concept and nature of complexity, information and biological organization, we look for some coordinated conceptual considerations corresponding to quantitative measures suitable to grasp the main characteristics of biological complexity. Quantitative measures of algorithmic complexity of supercomputers like Blue Gene/L are compared with the complexity of the brain. We show that both the computer and the brain have a more fundamental, dynamic complexity measure corresponding to the number of operations per second. Recent insights suggest that the origin of complexity may go back to simplicity at a deeper level, corresponding to algorithmic complexity. We point out that for physical systems Ashby’s Law, Kahre’s Law and causal closure of the physical exclude the generation of information, and since genetic information corresponds to instructions, we are faced with a controversy telling that the algorithmic complexity of physics is much lower than the instructions’ complexity of the human DNA: I_algorithmic(physics ~ 10^3 bit << I_instructions(DNA ~ 10^9 bit. Analyzing the genetic complexity we obtain that actually the genetic information corresponds to a deeper than algorithmic level of complexity, putting an even greater emphasis to the information paradox. We show that the resolution of the fundamental information paradox may lie either in the chemical evolution of inheritance in abiogenesis, or in the existence of an autonomous biological principle allowing the production of information beyond physics.

  8. Complexity of formation in holography

    Science.gov (United States)

    Chapman, Shira; Marrochio, Hugo; Myers, Robert C.

    2017-01-01

    It was recently conjectured that the quantum complexity of a holographic boundary state can be computed by evaluating the gravitational action on a bulk region known as the Wheeler-DeWitt patch. We apply this complexity=action duality to evaluate the `complexity of formation' [1, 2], i.e. the additional complexity arising in preparing the entangled thermofield double state with two copies of the boundary CFT compared to preparing the individual vacuum states of the two copies. We find that for boundary dimensions d > 2, the difference in the complexities grows linearly with the thermal entropy at high temperatures. For the special case d = 2, the complexity of formation is a fixed constant, independent of the temperature. We compare these results to those found using the complexity=volume duality.

  9. Complexity of Formation in Holography

    CERN Document Server

    Chapman, Shira; Myers, Robert C

    2016-01-01

    It was recently conjectured that the quantum complexity of a holographic boundary state can be computed by evaluating the gravitational action on a bulk region known as the Wheeler-DeWitt patch. We apply this complexity=action duality to evaluate the `complexity of formation' (arXiv:1509.07876, arXiv:1512.04993), i.e., the additional complexity arising in preparing the entangled thermofield double state with two copies of the boundary CFT compared to preparing the individual vacuum states of the two copies. We find that for boundary dimensions $d>2$, the difference in the complexities grows linearly with the thermal entropy at high temperatures. For the special case $d=2$, the complexity of formation is a fixed constant, independent of the temperature. We compare these results to those found using the complexity=volume duality.

  10. Complexity a very short introduction

    CERN Document Server

    Holland, John H

    2014-01-01

    The importance of complexity is well-captured by Hawking's comment: "Complexity is the science of the 21st century". From the movement of flocks of birds to the Internet, environmental sustainability, and market regulation, the study and understanding of complex non-linear systems has become highly influential over the last 30 years. In this Very Short Introduction, one of the leading figures in the field, John Holland, introduces the key elements and conceptual framework of complexity. From complex physical systems such as fluid flow and the difficulties of predicting weather, to complex adaptive systems such as the highly diverse and interdependent ecosystems of rainforests, he combines simple, well-known examples - Adam Smith's pin factory, Darwin's comet orchid, and Simon's 'watchmaker' - with an account of the approaches, involving agents and urn models, taken by complexity theory. ABOUT THE SERIES: The Very Short Introductions series from Oxford University Press contains hundreds of titles in almost eve...

  11. Complex Sleep Apnea Syndrome

    Directory of Open Access Journals (Sweden)

    Muhammad Talha Khan

    2014-01-01

    Full Text Available Complex sleep apnea is the term used to describe a form of sleep disordered breathing in which repeated central apneas (>5/hour persist or emerge when obstructive events are extinguished with positive airway pressure (PAP and for which there is not a clear cause for the central apneas such as narcotics or systolic heart failure. The driving forces in the pathophysiology are felt to be ventilator instability associated oscillation in PaCO2 arterial partial pressure of Carbon Dioxide, continuous cositive airway pressure (CPAP related increased CO2 carbon dioxide elimination, and activation of airway and pulmonary stretch receptors triggering these central apneas. The prevalence ranges from 0.56% to 18% with no clear predictive characteristics as compared to simple obstructive sleep apnea. Prognosis is similar to obstructive sleep apnea. The central apnea component in most patients on followup using CPAP therap, has resolved. For those with continued central apneas on simple CPAP therapy, other treatment options include bilevel PAP, adaptive servoventilation, permissive flow limitation and/or drugs.

  12. Complex emergencies in Indonesia.

    Science.gov (United States)

    Bradt, D A; Drummond, C M; Richman, M

    2001-01-01

    Recently, Indonesia has experienced six major provincial, civil, armed conflicts. Underlying causes include the transmigration policy, sectarian disputes, the Asian economic crisis, fall of authoritarian rule, and a backlash against civil and military abuses. The public health impact involves the displacement nationwide of > 1.2 million persons. Violence in the Malukus, Timor, and Kalimantan has sparked the greatest population movements such that five provinces in Indonesia each now harbor > 100,000 internally displaced persons. With a background of government instability, hyperinflation, macroeconomic collapse, and elusive political solutions, these civil armed conflicts are ripe for persistence as complex emergencies. Indonesia has made substantial progress in domestic disaster management with the establishment of central administrative authority, strategic planning, and training programs. Nevertheless, the Indonesian experience reveals recurrent issues in international humanitarian health assistance. Clinical care remains complicated by absences of treatment protocols, inappropriate drug use, high procedural complication rates, and variable referral practices. Epidemiological surveillance remains complicated by unsettled clinical case definitions, non-standardized case management of diseases with epidemic potential, variable outbreak management protocols, and inadequate epidemiological analytic capacity. International donor support has been semi-selective, insufficient, and late. The militia murders of three UN staff in West Timor prompted the withdrawal of UN international staff from West Timor for nearly a year to date. Re-establishing rules of engagement for humanitarian health workers must address security, public health, and clinical threats.

  13. Sociality influences cultural complexity.

    Science.gov (United States)

    Muthukrishna, Michael; Shulman, Ben W; Vasilescu, Vlad; Henrich, Joseph

    2014-01-01

    Archaeological and ethnohistorical evidence suggests a link between a population's size and structure, and the diversity or sophistication of its toolkits or technologies. Addressing these patterns, several evolutionary models predict that both the size and social interconnectedness of populations can contribute to the complexity of its cultural repertoire. Some models also predict that a sudden loss of sociality or of population will result in subsequent losses of useful skills/technologies. Here, we test these predictions with two experiments that permit learners to access either one or five models (teachers). Experiment 1 demonstrates that naive participants who could observe five models, integrate this information and generate increasingly effective skills (using an image editing tool) over 10 laboratory generations, whereas those with access to only one model show no improvement. Experiment 2, which began with a generation of trained experts, shows how learners with access to only one model lose skills (in knot-tying) more rapidly than those with access to five models. In the final generation of both experiments, all participants with access to five models demonstrate superior skills to those with access to only one model. These results support theoretical predictions linking sociality to cumulative cultural evolution.

  14. Information Complexity and Biology

    Science.gov (United States)

    Bagnoli, Franco; Bignone, Franco A.; Cecconi, Fabio; Politi, Antonio

    Kolmogorov contributed directly to Biology in essentially three problems: the analysis of population dynamics (Lotka-Volterra equations), the reaction-diffusion formulation of gene spreading (FKPP equation), and some discussions about Mendel's laws. However, the widely recognized importance of his contribution arises from his work on algorithmic complexity. In fact, the limited direct intervention in Biology reflects the generally slow growth of interest of mathematicians towards biological issues. From the early work of Vito Volterra on species competition, to the slow growth of dynamical systems theory, contributions to the study of matter and the physiology of the nervous system, the first 50-60 years have witnessed important contributions, but as scattered pieces apparently uncorrelated, and in branches often far away from Biology. Up to the 40' it is hard to see the initial loose build up of a convergence, for those theories that will become mainstream research by the end of the century, and connected by the study of biological systems per-se.

  15. Almost complex connections on almost complex manifolds with Norden metric

    OpenAIRE

    Teofilova, Marta

    2011-01-01

    A four-parametric family of linear connections preserving the almost complex structure is defined on an almost complex manifold with Norden metric. Necessary and sufficient conditions for these connections to be natural are obtained. A two-parametric family of complex connections is studied on a conformal K\\"{a}hler manifold with Norden metric. The curvature tensors of these connections are proved to coincide.

  16. Complexity measurement based on information theory and kolmogorov complexity.

    Science.gov (United States)

    Lui, Leong Ting; Terrazas, Germán; Zenil, Hector; Alexander, Cameron; Krasnogor, Natalio

    2015-01-01

    In the past decades many definitions of complexity have been proposed. Most of these definitions are based either on Shannon's information theory or on Kolmogorov complexity; these two are often compared, but very few studies integrate the two ideas. In this article we introduce a new measure of complexity that builds on both of these theories. As a demonstration of the concept, the technique is applied to elementary cellular automata and simulations of the self-organization of porphyrin molecules.

  17. Complexity management in projects between rational momentum and complex conditions

    DEFF Research Database (Denmark)

    Mac, Anita; Schlamovitz, Jesper

    This study takes its departure in a model of complexity, developed by Stacey (1993), to test and discuss its practical benefit as perceived by practicing project managers. Based on a survey, the study finds that complexity is a phenomenon recognized by project managers, and complexity management...... is associated with benefits in the development of tasks and managing stakeholders. It is also associated with some difficulty in terms of an increased need for dialogue and a risk of creating goal ambiguity. Based on the findings, we conclude that classical project management approaches can benefit from...... incorporating complexity management....

  18. Complexity Management In Projects Between Rational Momentum And Complex Conditions

    DEFF Research Database (Denmark)

    Mac, Anita; Schlamovitz, Jesper

    2015-01-01

    Abstract: This study takes its departure in a model of complexity, developed by Stacey (1993), to test and discuss its practical benefit as perceived by practicing project managers. Based on a survey, the study finds that complexity is a phenomenon recognized by project managers, and complexity...... management is associated with benefits in the development of tasks and managing stakeholders. It is also associated with some difficulty in terms of an increased need for dialogue and a risk of creating goal ambiguity. Based on the findings, we conclude that classical project management approaches can...... benefit from incorporating complexity management....

  19. Carney complex (CNC).

    Science.gov (United States)

    Bertherat, Jérôme

    2006-06-06

    The Carney complex (CNC) is a dominantly inherited syndrome characterized by spotty skin pigmentation, endocrine overactivity and myxomas. Skin pigmentation anomalies include lentigines and blue naevi. The most common endocrine gland manifestations are acromegaly, thyroid and testicular tumors, and adrenocorticotropic hormone (ACTH)-independent Cushing's syndrome due to primary pigmented nodular adrenocortical disease (PPNAD). PPNAD, a rare cause of Cushing's syndrome, is due to primary bilateral adrenal defect that can be also observed in some patients without other CNC manifestations or familial history of the disease. Myxomas can be observed in the heart, skin and breast. Cardiac myxomas can develop in any cardiac chamber and may be multiple. One of the putative CNC genes located on 17q22-24, (PRKAR1A), has been identified to encode the regulatory subunit (R1A) of protein kinase A. Heterozygous inactivating mutations of PRKAR1A were reported initially in 45 to 65% of CNC index cases, and may be present in about 80% of the CNC families presenting mainly with Cushing's syndrome. PRKAR1A is a key component of the cAMP signaling pathway that has been implicated in endocrine tumorigenesis and could, at least partly, function as a tumor suppressor gene. Genetic analysis should be proposed to all CNC index cases. Patients with CNC or with a genetic predisposition to CNC should have regular screening for manifestations of the disease. Clinical work-up for all the manifestations of CNC should be performed at least once a year in all patients and should start in infancy. Cardiac myxomas require surgical removal. Treatment of the other manifestations of CNC should be discussed and may include follow-up, surgery, or medical treatment depending on the location of the tumor, its size, the existence of clinical signs of tumor mass or hormonal excess, and the suspicion of malignancy. Bilateral adrenalectomy is the most common treatment for Cushing's syndrome due to PPNAD.

  20. Carney complex (CNC

    Directory of Open Access Journals (Sweden)

    Bertherat Jérôme

    2006-06-01

    Full Text Available Abstract The Carney complex (CNC is a dominantly inherited syndrome characterized by spotty skin pigmentation, endocrine overactivity and myxomas. Skin pigmentation anomalies include lentigines and blue naevi. The most common endocrine gland manifestations are acromegaly, thyroid and testicular tumors, and adrenocorticotropic hormone (ACTH-independent Cushing's syndrome due to primary pigmented nodular adrenocortical disease (PPNAD. PPNAD, a rare cause of Cushing's syndrome, is due to primary bilateral adrenal defect that can be also observed in some patients without other CNC manifestations or familial history of the disease. Myxomas can be observed in the heart, skin and breast. Cardiac myxomas can develop in any cardiac chamber and may be multiple. One of the putative CNC genes located on 17q22-24, (PRKAR1A, has been identified to encode the regulatory subunit (R1A of protein kinase A. Heterozygous inactivating mutations of PRKAR1A were reported initially in 45 to 65 % of CNC index cases, and may be present in about 80 % of the CNC families presenting mainly with Cushing's syndrome. PRKAR1A is a key component of the cAMP signaling pathway that has been implicated in endocrine tumorigenesis and could, at least partly, function as a tumor suppressor gene. Genetic analysis should be proposed to all CNC index cases. Patients with CNC or with a genetic predisposition to CNC should have regular screening for manifestations of the disease. Clinical work-up for all the manifestations of CNC should be performed at least once a year in all patients and should start in infancy. Cardiac myxomas require surgical removal. Treatment of the other manifestations of CNC should be discussed and may include follow-up, surgery, or medical treatment depending on the location of the tumor, its size, the existence of clinical signs of tumor mass or hormonal excess, and the suspicion of malignancy. Bilateral adrenalectomy is the most common treatment for Cushing

  1. Spatiotemporal Imaging of Complexity

    Directory of Open Access Journals (Sweden)

    Stephen Ellis Robinson

    2013-01-01

    Full Text Available What are the functional neuroimaging measurements required for more fully characterizing the events and locations of neocortical activity? A prime assumption has been that modulation of cortical activity will inevitably be reflected in changes in energy utilization (for the most part changes of glucose and oxygen consumption. Are such a measures complete and sufficient? More direct measures of cortical electrophysiological activity show event or task-related modulation of amplitude or band-limited oscillatory power. Using magnetoencephalography (MEG, these measures have been shown to correlate well with energy utilization sensitive BOLD fMRI. In this paper, we explore the existence of state changes in electrophysiological cortical activity that can occur independently of changes in averaged amplitude, source power or indices of metabolic rates. In addition, we demonstrate that such state changes can be described by applying a new measure of complexity, rank vector entropy (RVE, to source waveform estimates from beamformer-processed MEG. RVE is a non-parametric symbolic dynamic informational entropy measure that accommodates the wide dynamic range of measured brain signals while resolving its temporal variations. By representing the measurements by their rank values, RVE overcomes the problem of defining embedding space partitions without resorting to signal compression. This renders RVE independent of absolute signal amplitude. In addition, this approach is robust, being relatively free of tunable parameters. We present examples of task-free and task dependent MEG demonstrating that RVE provides new information by uncovering hidden dynamical struc-ture in the apparent turbulent (or chaotic dynamics of spontaneous cortical activity.

  2. ON COMPLEX DYNAMIC CONTROL SYSTEMS

    Institute of Scientific and Technical Information of China (English)

    CHENG Daizhan

    2003-01-01

    This paper presents some recent works on the control of dynamic systems, which have certain complex properties caused by singularity of the nonlinear structures, structure-varyings, or evolution process etc. First, we consider the structure singularity of nonlinear control systems. It was revealed that the focus of researches on nonlinear control theory is shifting from regular systems to singular systems. The singularity of nonlinear systems causes certain complexity. Secondly, the switched systems are considered. For such systems the complexity is caused by the structure varying. We show that the switched systems have significant characteristics of complex systems. Finally, we investigate the evolution systems. The evolution structure makes complexity, and itself is a proper model for complex systems.

  3. Increasing complexity with quantum physics.

    Science.gov (United States)

    Anders, Janet; Wiesner, Karoline

    2011-09-01

    We argue that complex systems science and the rules of quantum physics are intricately related. We discuss a range of quantum phenomena, such as cryptography, computation and quantum phases, and the rules responsible for their complexity. We identify correlations as a central concept connecting quantum information and complex systems science. We present two examples for the power of correlations: using quantum resources to simulate the correlations of a stochastic process and to implement a classically impossible computational task.

  4. Report: Genetics of complex diseases

    Institute of Scientific and Technical Information of China (English)

    MOTULSKY Arno G.

    2006-01-01

    Approaches to the study of the genetic basis of common complex diseases and their clinical applications are considered. Monogenic Mendelian inheritance in such conditions is infrequent but its elucidation may help to detect pathogenic mechanisms in the more common variety of complex diseases. Involvement by multiple genes in complex diseases usually occurs but the isolation and identification of specific genes so far has been exceptional. The role of common polymorphisms as indicators of disease risk in various studies is discussed.

  5. SYNCHRONIZATION IN COMPLEX DYNAMICAL NETWORKS

    Institute of Scientific and Technical Information of China (English)

    WANG Xiaofan; CHEN Guanrong

    2003-01-01

    In the past few years, the discovery of small-world and scale-free properties of many natural and artificial complex networks has stimulated increasing interest in further studying the underlying organizing principles of various complex networks. This has led to significant advances in understanding the relationship between the topology and the dynamics of such complex networks. This paper reviews some recent research works on the synchronization phenomenon in various dynamical networks with small-world and scalefree connections.

  6. On the interaction meteor complex

    Science.gov (United States)

    Rajchl, J.

    An approach to the problem of a meteoric complex called the interaction meteor complex (IMC) is applied and discussed, generalizing the idea of the interaction layer (Rajchl 1969). The role of an extended interaction of meteoroids is emphasized, both with planet surfaces and/or their satellites and with planet atmospheres, elastic or inelastic in form. The dissipation and related formative aspect are joined in one complex and compared with a topological compact. Examples of these types of interaction are presented.

  7. Measuring Complexity through Average Symmetry

    OpenAIRE

    Alamino, Roberto C.

    2015-01-01

    This work introduces a complexity measure which addresses some conflicting issues between existing ones by using a new principle - measuring the average amount of symmetry broken by an object. It attributes low (although different) complexity to either deterministic or random homogeneous densities and higher complexity to the intermediate cases. This new measure is easily computable, breaks the coarse graining paradigm and can be straightforwardly generalised, including to continuous cases an...

  8. Kolmogorov Complexity, Causality And Spin

    CERN Document Server

    Shayda, Dara O

    2012-01-01

    A novel topological and computational method for 'motion' is described. Motion is constrained by inequalities in terms of Kolmogorov Complexity. Causality is obtained as the output of a high-pass filter, passing through only high values of Kolmogorov Complexity. Motion under the electromagnetic field described with immediate relationship with Subscript[G, 2] Holonomy group and its corresponding dense free 2-subgroup. Similar to Causality, Spin emerges as an immediate and inevitable consequence of high values of Kolmogorov Complexity. Consequently, the physical laws are nothing but a low-pass filter for small values of Kolmogorov Complexity.

  9. Measuring Complexity of SAP Systems

    Directory of Open Access Journals (Sweden)

    Ilja Holub

    2016-10-01

    Full Text Available The paper discusses the reasons of complexity rise in ERP system SAP R/3. It proposes a method for measuring complexity of SAP. Based on this method, the computer program in ABAP for measuring complexity of particular SAP implementation is proposed as a tool for keeping ERP complexity under control. The main principle of the measurement method is counting the number of items or relations in the system. The proposed computer program is based on counting of records in organization tables in SAP.

  10. Technetium-aspirin molecule complexes

    Energy Technology Data Exchange (ETDEWEB)

    El-Shahawy, A.S.; Mahfouz, R.M.; Aly, A.A.M.; El-Zohry, M. (Assiut Univ. (Egypt))

    1993-01-01

    Technetium-aspirin and technetium-aspirin-like molecule complexes were prepared. The structure of N-acetylanthranilic acid (NAA) has been decided through CNDO calculations. The ionization potential and electron affinity of the NAA molecule as well as the charge densities were calculated. The electronic absorption spectra of Tc(V)-Asp and Tc(V)-ATS complexes have two characteristic absorption bands at 450 and 600 nm, but the Tc(V)-NAA spectrum has one characteristic band at 450 nm. As a comparative study, Mo-ATS complex was prepared and its electronic absorption spectrum is comparable with the Tc-ATS complex spectrum. (author).

  11. Cyclomatic Complexity: theme and variations

    Directory of Open Access Journals (Sweden)

    Brian Henderson-Sellers

    1993-11-01

    Full Text Available Focussing on the "McCabe family" of measures for the decision/logic structure of a program, leads to an evaluation of extensions to modularization, nesting and, potentially, to object-oriented program structures. A comparison of rated, operating and essential complexities of programs suggests two new metrics: "inessential complexity" as a measure of unstructuredness and "product complexity" as a potential objective measure of structural complexity. Finally, nesting and abstraction levels are considered, especially as to how metrics from the "McCabe family" might be applied in an object-oriented systems development environment.

  12. Complex Constructivism: A Theoretical Model of Complexity and Cognition

    Science.gov (United States)

    Doolittle, Peter E.

    2014-01-01

    Education has long been driven by its metaphors for teaching and learning. These metaphors have influenced both educational research and educational practice. Complexity and constructivism are two theories that provide functional and robust metaphors. Complexity provides a metaphor for the structure of myriad phenomena, while constructivism…

  13. Waves in complex systems

    Science.gov (United States)

    Xie, Hang

    The theme of this thesis is the study of wave phenomena in complex systems. In particular, the following three topics constitute the foci of my research. The first topic involves the generalization of an electronic transport mechanism commonly observed in disordered media, fluctuation induced tunneling conduction, by considering tunneling through not just insulating potential barriers, but also narrow conducting channels. Here the wave nature of the electron implies that a narrow conduction channel can act as an electronic waveguide, with a cutoff transverse dimension that is half the Fermi wavelength. My research involves the study of electronic transport through finite-length conducting channels with transverse dimensions below the cutoff. Such narrow conduction channel may be physically realized by chains of single conducting atoms, for example. At small voltage bias across the conduction channel, only tunneling transport is possible at zero temperature. But at finite temperatures some of the electrons with energies above the Fermi level can ballistically transport across the channel. By considering both tunneling and thermal activation mechanisms, with thermally-generated (random) voltage bias across the narrow channel, we obtained a temperature-dependent conductivity behavior that is in good agreement with the measured two-lead conductance of RuO2 and IrO2 nanowires. Furthermore, by considering high applied voltage across the nano conduction channels, our model predicts interesting electronic Fabry-Perot behavior whose experimental verification is presently underway. The second topic involves the study of the Hall effect in mesoscopic samples. In particular, we are interested in the possibility of enhancing the Hall effect by nano-patterning samples of 2D electron gas. Through numerical solution of the Schrodinger equation in the presence of a magnetic field, mesoscopic transport behavior is obtained for samples with given geometric patterns of the

  14. Improve Reading with Complex Texts

    Science.gov (United States)

    Fisher, Douglas; Frey, Nancy

    2015-01-01

    The Common Core State Standards have cast a renewed light on reading instruction, presenting teachers with the new requirements to teach close reading of complex texts. Teachers and administrators should consider a number of essential features of close reading: They are short, complex texts; rich discussions based on worthy questions; revisiting…

  15. Team dynamics in complex projects

    NARCIS (Netherlands)

    Oeij, P.; Vroome, E.E.M. de; Dhondt, S.; Gaspersz, J.B.R.

    2012-01-01

    Complexity of projects is hotly debated and a factor which affects innovativeness of team performance. Much attention in the past is paid to technical complexity and many issues are related to natural and physical sciences. A growing awareness of the importance of socioorganisational issues is annou

  16. Complexity regularized hydrological model selection

    NARCIS (Netherlands)

    Pande, S.; Arkesteijn, L.; Bastidas, L.A.

    2014-01-01

    This paper uses a recently proposed measure of hydrological model complexity in a model selection exercise. It demonstrates that a robust hydrological model is selected by penalizing model complexity while maximizing a model performance measure. This especially holds when limited data is available.

  17. Holistic education and complexity thinking

    NARCIS (Netherlands)

    Jörg, T.

    2007-01-01

    Paper proposal for the SIG Holistic Education at AERA 2007 Title: Holistic Education and Complexity Thinking Ton Jörg IVLOS Institute of Education University of Utrecht The Netherlands A.G.D.Jorg@ivlos.uu.nl ABSTRACT In this paper I link complexity thinking with Holistic Education (HE). It is a chal

  18. Complex Data: Mining using Patterns

    NARCIS (Netherlands)

    Siebes, A.P.J.M.; Struzik, Z.R.

    2002-01-01

    There is a growing need to analyse sets of complex data, i.e., data in which the individual data items are (semi-) structured collections of data themselves, such as sets of time-series. To perform such analysis, one has to redefine familiar notions such as similarity on such complex data types. One

  19. How to lead complex situations

    DEFF Research Database (Denmark)

    Hansen, Michael Pingel

    2013-01-01

    The military leader is experiencing increasingly more complex situations, whether it is as leader in a foreign combat environment or in the home-based public administration. Complex situations like these call for a special set of managerial responses and a special way of leading organisations...

  20. The Algebra of Complex Numbers.

    Science.gov (United States)

    LePage, Wilbur R.

    This programed text is an introduction to the algebra of complex numbers for engineering students, particularly because of its relevance to important problems of applications in electrical engineering. It is designed for a person who is well experienced with the algebra of real numbers and calculus, but who has no experience with complex number…

  1. Electrochemical analysis of metal complexes.

    NARCIS (Netherlands)

    Jong, de H.G.

    1987-01-01

    The present study is concerned with the electroanalytical chemistry of complexes of metals with large ligands. The main purpose was to develop quantitative descriptions of the voltammetric current-potential relation of metal complex systems with different diffusion coefficients of the species involv

  2. Complex multiplication of abelian surfaces

    NARCIS (Netherlands)

    Streng, Theodorus Cornelis

    2010-01-01

    The theory of complex multiplication makes it possible to construct certain class fields and abelian varieties. The main theme of this thesis is making these constructions explicit for the case where the abelian varieties have dimension 2. Chapter I is an introduction to complex multiplication

  3. Complexity Results in Epistemic Planning

    DEFF Research Database (Denmark)

    Bolander, Thomas; Jensen, Martin Holm; Schwarzentruber, Francois

    2015-01-01

    Epistemic planning is a very expressive framework that extends automated planning by the incorporation of dynamic epistemic logic (DEL). We provide complexity results on the plan existence problem for multi-agent planning tasks, focusing on purely epistemic actions with propositional preconditions......-hardness of the plan verification problem, which strengthens previous results on the complexity of DEL model checking....

  4. Complex Variables in Secondary Schools

    Science.gov (United States)

    Dwyer, Jerry; Moskal, Barbara; Duke, Billy; Wilhelm, Jennifer

    2007-01-01

    This article describes the work of outreach mathematicians introducing the topic of complex variables to eighth and ninth grade students (13- to 15-year-olds) in the US. Complex variables is an area of mathematics that is not typically studied at secondary level. The authors developed seven lessons designed to stimulate students' interest in…

  5. Teacher Knowledge: A Complex Tapestry

    Science.gov (United States)

    Adoniou, Misty

    2015-01-01

    Teachers need to know a great deal, in many areas and in multiple ways. Teacher knowledge is a complex tapestry, and teachers must successfully weave the multiple threads. In this article, I present a conceptualisation of teacher knowledge that provides a framework for describing the complexity of teacher knowledge. The framework describes three…

  6. Too Dumb for Complex Texts?

    Science.gov (United States)

    Bauerlein, Mark

    2011-01-01

    High school students' lack of experience and practice with reading complex texts is a primary cause of their difficulties with college-level reading. Filling the syllabus with digital texts does little to address this deficiency. Complex texts demand three dispositions from readers: a willingness to probe works characterized by dense meanings, the…

  7. Multi-Timescale Complex Adaptation

    Science.gov (United States)

    2006-03-01

    interconnected gene and biochemical regulatory networks. Attempts at reverse engineering the gene regulatory networks from microarray data alone...are considered as potentially regulating all the other genes and the suboptimal and nonunique results are subsequently pruned either by setting...postulate that systems engineering techniques developed for complex chemical processes may be applicable to complex cell biological processes is very

  8. Copper complexes as chemical nucleases

    Indian Academy of Sciences (India)

    Akhil R Chakravarty; Pattubala A N Reddy; Bidyut K Santra; Anitha M Thomas

    2002-08-01

    Redox active mononuclear and binuclear copper(II) complexes have been prepared and structurally characterized. The complexes have planar N-donor heterocyclic bases like 1,10-phenanthroline (phen), dipyridoquinoxaline (dpq) and dipyridophenazine (dppz) ligands that are suitable for intercalation to B-DNA. Complexes studied for nuclease activity have the formulations [Cu(dpq)2(H2O)] (ClO4)2.H2O (1), [{CuL(H2O)}2(-ox)](ClO4)2 (L = bpy, 2; phen, 3; dpq, 4; and dppz, 5) and [Cu(L)(salgly)] (L = bpy, 6; phen, 7; dpq, 8; and dppz, 9), where salgly is a tridentate Schiff base obtained from the condensation of glycine and salicylaldehyde. The dpq complexes are efficient DNA binding and cleavage active species. The dppz complexes show good binding ability but poor nuclease activity. The cleavage activity of the bis-dpq complex is significantly higher than the bis-phen complex of copper(II). The nuclease activity is found to be dependent on the intercalating nature of the complex and on the redox potential of the copper(II)/copper(I) couple. The ancillary ligand plays a significant role in binding and cleavage activity.

  9. Game interpretation of Kolmogorov complexity

    CERN Document Server

    Muchnik, Andrej A; Shen, Alexander; Vereshchagin, Nikolay

    2010-01-01

    The Kolmogorov complexity function K can be relativized using any oracle A, and most properties of K remain true for relativized versions. In section 1 we provide an explanation for this observation by giving a game-theoretic interpretation and showing that all "natural" properties are either true for all sufficiently powerful oracles or false for all sufficiently powerful oracles. This result is a simple consequence of Martin's determinacy theorem, but its proof is instructive: it shows how one can prove statements about Kolmogorov complexity by constructing a special game and a winning strategy in this game. This technique is illustrated by several examples (total conditional complexity, bijection complexity, randomness extraction, contrasting plain and prefix complexities).

  10. European Conference on Complex Systems

    CERN Document Server

    Pellegrini, Francesco; Caldarelli, Guido; Merelli, Emanuela

    2016-01-01

    This work contains a stringent selection of extended contributions presented at the meeting of 2014 and its satellite meetings, reflecting scope, diversity and richness of research areas in the field, both fundamental and applied. The ECCS meeting, held under the patronage of the Complex Systems Society, is an annual event that has become the leading European conference devoted to complexity science. It offers cutting edge research and unique opportunities to study novel scientific approaches in a multitude of application areas. ECCS'14, its eleventh occurrence, took place in Lucca, Italy. It gathered some 650 scholars representing a wide range of topics relating to complex systems research, with emphasis on interdisciplinary approaches. The editors are among the best specialists in the area. The book is of great interest to scientists, researchers and graduate students in complexity, complex systems and networks.

  11. Managing complexity insights, concepts, applications

    CERN Document Server

    Helbing, Dirk

    2007-01-01

    Each chapter in Managing Complexity focuses on analyzing real-world complex systems and transferring knowledge from the complex-systems sciences to applications in business, industry and society. The interdisciplinary contributions range from markets and production through logistics, traffic control, and critical infrastructures, up to network design, information systems, social conflicts and building consensus. They serve to raise readers' awareness concerning the often counter-intuitive behavior of complex systems and to help them integrate insights gained in complexity research into everyday planning, decision making, strategic optimization, and policy. Intended for a broad readership, the contributions have been kept largely non-technical and address a general, scientifically literate audience involved in corporate, academic, and public institutions.

  12. Innovation in a complex environment

    Directory of Open Access Journals (Sweden)

    René Pellissier

    2012-02-01

    Full Text Available Background: As our world becomes more global and competitive yet less predictable, the focus seems to be increasingly on looking to innovation activities to remain competitive. Although there is little doubt that a nation’s competitiveness is embedded in its innovativeness, the complex environment should not be ignored. Complexity is not accounted for in balance sheets or reported in reports; it becomes entrenched in every activity in the organisation. Innovation takes many forms and comes in different shapes.Objectives: The study objectives were, firstly, to establish the determinants for complexity and how these can be addressed from a design point of view in order to ensure innovation success and, secondly, to determine how this changes innovation forms and applications.Method: Two approaches were offered to deal with a complex environment – one allowing for complexity for organisational innovation and the other introducing reductionism to minimise complexity. These approaches were examined in a qualitative study involving case studies, open-ended interviews and content analysis between seven developing economy (South African organisations and seven developed economy (US organisations.Results: This study presented a proposed framework for (organisational innovation in a complex environment versus a framework that minimises complexity. The comparative organisational analysis demonstrated the importance of initiating organisational innovation to address internal and external complexity, with the focus being on the leadership actions, their selected operating models and resultant organisational innovations designs, rather than on technological innovations.Conclusion: This study cautioned the preference for technological innovation within organisations and suggested alternative innovation forms (such as organisational and management innovation be used to remain competitive in a complex environment. 

  13. Complex coacervation: A field theoretic simulation study of polyelectrolyte complexation

    Science.gov (United States)

    Lee, Jonghoon; Popov, Yuri O.; Fredrickson, Glenn H.

    2008-06-01

    Using the complex Langevin sampling strategy, field theoretic simulations are performed to study the equilibrium phase behavior and structure of symmetric polycation-polyanion mixtures without salt in good solvents. Static structure factors for the segment density and charge density are calculated and used to study the role of fluctuations in the electrostatic and chemical potential fields beyond the random phase approximation. We specifically focus on the role of charge density and molecular weight on the structure and complexation behavior of polycation-polyanion solutions. A demixing phase transition to form a ``complex coacervate'' is observed in strongly charged systems, and the corresponding spinodal and binodal boundaries of the phase diagram are investigated.

  14. Modelling of Complex Plasmas

    Science.gov (United States)

    Akdim, Mohamed Reda

    2003-09-01

    Nowadays plasmas are used for various applications such as the fabrication of silicon solar cells, integrated circuits, coatings and dental cleaning. In the case of a processing plasma, e.g. for the fabrication of amorphous silicon solar cells, a mixture of silane and hydrogen gas is injected in a reactor. These gases are decomposed by making a plasma. A plasma with a low degree of ionization (typically 10_5) is usually made in a reactor containing two electrodes driven by a radio-frequency (RF) power source in the megahertz range. Under the right circumstances the radicals, neutrals and ions can react further to produce nanometer sized dust particles. The particles can stick to the surface and thereby contribute to a higher deposition rate. Another possibility is that the nanometer sized particles coagulate and form larger micron sized particles. These particles obtain a high negative charge, due to their large radius and are usually trapped in a radiofrequency plasma. The electric field present in the discharge sheaths causes the entrapment. Such plasmas are called dusty or complex plasmas. In this thesis numerical models are presented which describe dusty plasmas in reactive and nonreactive plasmas. We started first with the development of a simple one-dimensional silane fluid model where a dusty radio-frequency silane/hydrogen discharge is simulated. In the model, discharge quantities like the fluxes, densities and electric field are calculated self-consistently. A radius and an initial density profile for the spherical dust particles are given and the charge and the density of the dust are calculated with an iterative method. During the transport of the dust, its charge is kept constant in time. The dust influences the electric field distribution through its charge and the density of the plasma through recombination of positive ions and electrons at its surface. In the model this process gives an extra production of silane radicals, since the growth of dust is

  15. Three Types of Network Complexity Pyramid

    Institute of Scientific and Technical Information of China (English)

    FANG; Jin-qing; LI; Yong; LIU; Qiang

    2012-01-01

    <正>Exploring the complexity and diversity of complex networks have been very challenging issues in network science and engineering. Among them exploring the network complexity pyramids (NCP) are one of important expressions in network complexity. So far as we have proposed the three types of the network complexity pyramid (NCP). The first type of NCP is the network model complexity pyramid with

  16. Complex Convexity of Orlicz Modular Sequence Spaces

    Directory of Open Access Journals (Sweden)

    Lili Chen

    2016-01-01

    Full Text Available The concepts of complex extreme points, complex strongly extreme points, complex strict convexity, and complex midpoint locally uniform convexity in general modular spaces are introduced. Then we prove that, for any Orlicz modular sequence space lΦ,ρ, lΦ,ρ is complex midpoint locally uniformly convex. As a corollary, lΦ,ρ is also complex strictly convex.

  17. Formulation of Complex Action Theory

    CERN Document Server

    Nagao, Keiichi

    2011-01-01

    We formulate the complex action theory from a fundamental level so that we can deal with a complex coordinate $q$ and a complex momentum $p$. We extend $| q >$ and $| p>$ to complex $q$ and $p$ by utilizing coherent states of harmonic oscillators. Introducing a philosophy to keep the analyticity in parameter variables of Feynman path integral, we define a modified set of complex conjugate, real and imaginary parts, hermitian conjugates and bras. They enable us to have both orthogonality and completeness relations for $|q >$ and $|p >$ with complex $q$ and $p$. We also pose a theorem on the relation between functions and operators to make it clear to some extent. Furthermore, extending our previous work \\cite{Nagao:2010xu} to the complex coordinate case, we study a system defined by a diagonalizable non-hermitian bounded Hamiltonian, and show that a hermitian Hamiltonian is effectively obtained after a long time development by introducing a proper inner product. If the hermitian Hamiltonian is given in a local...

  18. 3D complex: a structural classification of protein complexes.

    Directory of Open Access Journals (Sweden)

    Emmanuel D Levy

    2006-11-01

    Full Text Available Most of the proteins in a cell assemble into complexes to carry out their function. It is therefore crucial to understand the physicochemical properties as well as the evolution of interactions between proteins. The Protein Data Bank represents an important source of information for such studies, because more than half of the structures are homo- or heteromeric protein complexes. Here we propose the first hierarchical classification of whole protein complexes of known 3-D structure, based on representing their fundamental structural features as a graph. This classification provides the first overview of all the complexes in the Protein Data Bank and allows nonredundant sets to be derived at different levels of detail. This reveals that between one-half and two-thirds of known structures are multimeric, depending on the level of redundancy accepted. We also analyse the structures in terms of the topological arrangement of their subunits and find that they form a small number of arrangements compared with all theoretically possible ones. This is because most complexes contain four subunits or less, and the large majority are homomeric. In addition, there is a strong tendency for symmetry in complexes, even for heteromeric complexes. Finally, through comparison of Biological Units in the Protein Data Bank with the Protein Quaternary Structure database, we identified many possible errors in quaternary structure assignments. Our classification, available as a database and Web server at http://www.3Dcomplex.org, will be a starting point for future work aimed at understanding the structure and evolution of protein complexes.

  19. Epidemic Diffusion on Complex Networks

    Institute of Scientific and Technical Information of China (English)

    WU Xiao-Yan; LIU Zong-Hua

    2007-01-01

    Boyh diffusion and epidemic are well studied in the stochastic systems and complex networks,respetively.Here we combine these two fields and study epidemic diffusion in complex networks.Instead of studying the threshold of infection,which was focused on in previous works,we focus on the diffusion.behaviour.We find that the epidemic diffusion in a complex network is an anomalous superdiffusion with varyingg diffusion exponext γand that γ is influenced seriously by the network structure,such as the clustering coefficient and the degree distribution.Numerical simulations have confirmed the theoretical predictions.

  20. Quantum Tunneling and Complex Trajectories

    Science.gov (United States)

    Meynig, Max; Haggard, Hal

    2017-01-01

    In general, the semiclassical approximation of quantum mechanical tunneling fails to treat tunneling through barriers if real initial conditions and trajectories are used. By analytically continuing classical dynamics to the complex plane the problems encountered in the approximation can be resolved. While, the complex methods discussed here have been previously explored, no one has exhibited an analytically solvable case. The essential features of the complex method will be discussed in the context of a novel, analytically solvable problem. These methods could be useful in quantum gravity, with applications to the tunneling of spacetime geometries.

  1. Complexity and Shock Wave Geometries

    CERN Document Server

    Stanford, Douglas

    2014-01-01

    In this paper we refine a conjecture relating the time-dependent size of an Einstein-Rosen bridge to the computational complexity of the of the dual quantum state. Our refinement states that the complexity is proportional to the spatial volume of the ERB. More precisely, up to an ambiguous numerical coefficient, we propose that the complexity is the regularized volume of the largest codimension one surface crossing the bridge, divided by $G_N l_{AdS}$. We test this conjecture against a wide variety of spherically symmetric shock wave geometries in different dimensions. We find detailed agreement.

  2. Scattering methods in complex fluids

    CERN Document Server

    Chen, Sow-Hsin

    2015-01-01

    Summarising recent research on the physics of complex liquids, this in-depth analysis examines the topic of complex liquids from a modern perspective, addressing experimental, computational and theoretical aspects of the field. Selecting only the most interesting contemporary developments in this rich field of research, the authors present multiple examples including aggregation, gel formation and glass transition, in systems undergoing percolation, at criticality, or in supercooled states. Connecting experiments and simulation with key theoretical principles, and covering numerous systems including micelles, micro-emulsions, biological systems, and cement pastes, this unique text is an invaluable resource for graduate students and researchers looking to explore and understand the expanding field of complex fluids.

  3. Complexity in physics and technology

    CERN Document Server

    Garrido, Manuel S

    1992-01-01

    A system is loosely defined as complex if it is composed of a large number of elements, interacting with each other, and the emergent global dynamics is qualitatively different from the dynamics of each one of the parts. The global dynamics may be either ordered or chaotic and among the most interesting emergent global properties are those of learning and adaptation.Complex systems, in the above sense, appear in many fields ranging from physics and technology to life and social sciences. Research in complex systems involves therefore a wide range of topics, studied in seemingly disparate field

  4. Hydrophysical laser-interference complex

    Directory of Open Access Journals (Sweden)

    Sergey V. Yakovenko

    2016-12-01

    Full Text Available A new hydrophysical measuring complex has been developed on the basis of a laser instrument for measuring hydrospheric pressure variations. The complex was previously engineered and experimentally verified. This equipment allows to investigate the amplitude-phase variations of hydrospheric vibrations and waves in the low-frequency range. All performance data of the complex was considerably improved by virtue of the operating experience obtained previously. Radically new opportunities of the equipment were provided since the apparatus was rigged with new sensors for accompanying measurements and a container which allowed working independently. The new hydrophysical measuring complex is easier to operate and maintain, ensures higher quality of the data obtained and new spheres of application.

  5. Liquid-crystalline lanthanide complexes

    OpenAIRE

    Binnemans, Koen

    1999-01-01

    The paper describes the recent developments in the field of liquid-crystalline lanthanide complexes. The role of trivalent lanthanide ions as the central metal ion in metallomesogens is considered. An outlook for the future is given.

  6. Formulation of Complex Action Theory

    OpenAIRE

    Nagao, Keiichi; Nielsen, Holger Bech

    2011-01-01

    We formulate a complex action theory which includes operators of coordinate and momentum $\\hat{q}$ and $\\hat{p}$ being replaced with non-hermitian operators $\\hat{q}_{new}$ and $\\hat{p}_{new}$, and their eigenstates ${}_m

  7. Unitarity and Complex Mass Fields

    Science.gov (United States)

    Bollini, C. G.; Oxman, L. E.

    We consider a field obeying a simple higher order equation with a real mass and two complex conjugate mass parameters. The evaluation of vacuum expectation values leads to the propagators, which are (resp.) a Feynman causal function and two complex conjugate Wheeler-Green functions (half retarded plus half advanced). By means of the computation of convolutions, we are able to show that the total self-energy has an absorptive part which is only due to the real mass. In this way it is shown that this diagram is compatible with unitarity and the elimination of free complex-mass asymptotic states from the set of external legs of the S-matrix. It is also shown that the complex masses act as regulators of ultraviolet divergences.

  8. Project Dynamics and Emergent Complexity

    CERN Document Server

    Schlick, Christopher M

    2011-01-01

    The present paper presents theoretical and empirical analyses of project dynamics and emergent complexity in new product development (NPD) projects. A model-driven approach was taken and a vector autoregression (VAR) model of cooperative task processing was formulated. The model is explained and validated based on an empirical study carried out in a industrial company. Furthermore, concepts and measures of complex systems science were reviewed and applied to project management. To evaluate emergent complexity in NPD projects, an information-theory quantity -termed "effective measure complexity" (EMC)- was selected, because it can be derived from first principles and therefore has high construct validity. Furthermore, EMC can be calculated efficiently from generative models of task processing or purely from historical data, without intervening models. EMC measures the mutual information between the infinite past and future histories of a stochastic process. According to this principle, it is particularly inter...

  9. Management recommendations: Benton Lake Complex

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document is a review of land management practices at the Benton Lake Complex, by a land use specialist. Recommendations, time frame and additional comments are...

  10. Coarse-graining complex dynamics

    DEFF Research Database (Denmark)

    Sibani, Paolo

    2013-01-01

    Continuous Time Random Walks (CTRW) are widely used to coarse-grain the evolution of systems jumping from a metastable sub-set of their configuration space, or trap, to another via rare intermittent events. The multi-scaled behavior typical of complex dynamics is provided by a fat-tailed distribu......Continuous Time Random Walks (CTRW) are widely used to coarse-grain the evolution of systems jumping from a metastable sub-set of their configuration space, or trap, to another via rare intermittent events. The multi-scaled behavior typical of complex dynamics is provided by a fat......-law and logarithmic relaxation behaviors ubiquitous in complex dynamics, together with the sub-diffusive time dependence of the Mean Square Displacement characteristic of single particles moving in a complex environment....

  11. Anomaly Detection for Complex Systems

    Data.gov (United States)

    National Aeronautics and Space Administration — In performance maintenance in large, complex systems, sensor information from sub-components tends to be readily available, and can be used to make predictions about...

  12. Complex Terrain and Wind Lidars

    DEFF Research Database (Denmark)

    Bingöl, Ferhat

    This thesis includes the results of a PhD study about complex terrain and wind lidars. The study mostly focuses on hilly and forested areas. Lidars have been used in combination with cups, sonics and vanes, to reach the desired vertical measurement heights. Several experiments are performed...... in complex terrain sites and the measurements are compared with two different flow models; a linearised flow model LINCOM and specialised forest model SCADIS. In respect to the lidar performance in complex terrain, the results showed that horizontal wind speed errors measured by a conically scanning lidar....... The SCADIS model worked better than the LINCOM model at the forest edge but the model reported closer results to the measurements at upwind than the downwind and this should be noted as a limitation of the model. As the general conclusion of the study, it was stated that the lidars can be used in complex...

  13. Complex Topographic Feature Ontology Patterns

    Science.gov (United States)

    Varanka, Dalia E.; Jerris, Thomas J.

    2015-01-01

    Semantic ontologies are examined as effective data models for the representation of complex topographic feature types. Complex feature types are viewed as integrated relations between basic features for a basic purpose. In the context of topographic science, such component assemblages are supported by resource systems and found on the local landscape. Ontologies are organized within six thematic modules of a domain ontology called Topography that includes within its sphere basic feature types, resource systems, and landscape types. Context is constructed not only as a spatial and temporal setting, but a setting also based on environmental processes. Types of spatial relations that exist between components include location, generative processes, and description. An example is offered in a complex feature type ‘mine.’ The identification and extraction of complex feature types are an area for future research.

  14. Challenges in Complex Systems Science

    CERN Document Server

    Miguel, Maxi San; Kertesz, Janos; Kaski, Kimmo; Díaz-Guilera, Albert; MacKay, Robert S; Loreto, Vittorio; Erdi, Peter; Helbing, Dirk

    2012-01-01

    FuturICT foundations are social science, complex systems science, and ICT. The main concerns and challenges in the science of complex systems in the context of FuturICT are laid out in this paper with special emphasis on the Complex Systems route to Social Sciences. This include complex systems having: many heterogeneous interacting parts; multiple scales; complicated transition laws; unexpected or unpredicted emergence; sensitive dependence on initial conditions; path-dependent dynamics; networked hierarchical connectivities; interaction of autonomous agents; self-organisation; non-equilibrium dynamics; combinatorial explosion; adaptivity to changing environments; co-evolving subsystems; ill-defined boundaries; and multilevel dynamics. In this context, science is seen as the process of abstracting the dynamics of systems from data. This presents many challenges including: data gathering by large-scale experiment, participatory sensing and social computation, managing huge distributed dynamic and heterogeneou...

  15. ON COMPLEXITY OF POWER SYSTEMS

    Institute of Scientific and Technical Information of China (English)

    MA Jin; CHENG Daizhan; HONG Yiguang; SUN Yuanzhang

    2003-01-01

    The power system is a classical example of complex systems. In this paper it is shown that the power industry in China is facing a tremendous challenge. The complexity in power systems is investigated as follows. First, the cascade failure in power systems is analyzed, and compared with sand-pile model. Next, we show that the agent-based modelling is a proper way for power network. Mathematically, the geometric dynamics and differential inclusion are useful tools for the stability analysis of large scale power systems. As for power market, the game theory and generalized control system model are proposed. For a complex power system, an evolutive model may be more accurate in description and analysis. Finally, certain newly developed numerical methods in the power system computation are introduced. Overall, we are convinced that the theorem of complexity, combined with modern control theory, may be the right way to answer the challenges faced by the power industry in China.

  16. Immobile Complex Verbs in Germanic

    DEFF Research Database (Denmark)

    Vikner, Sten

    2005-01-01

    Certain complex verbs in Dutch, German, and Swiss German do not undergo verb movement. The suggestion to be made in this article is that these ‘‘immobile'' verbs have to fulfill both the requirements imposed on complex verbs of the V° type (=verbs with non-separable prefixes) and the requirements...... are immobile, - why such verbs are not found in Germanic VO-languages such as English and Scandinavian.......Certain complex verbs in Dutch, German, and Swiss German do not undergo verb movement. The suggestion to be made in this article is that these ‘‘immobile'' verbs have to fulfill both the requirements imposed on complex verbs of the V° type (=verbs with non-separable prefixes) and the requirements...

  17. Why Quantum Theory is Complex

    CERN Document Server

    Goyal, Philip; Skilling, John

    2009-01-01

    Complex numbers are an intrinsic part of the mathematical formalism of quantum theory, and are perhaps its most mysterious feature. In this paper, we show that it is possible to derive the complex nature of the quantum formalism directly from the assumption that a pair of real numbers is associated to each sequence of measurement outcomes, and that the probability of this sequence is a real-valued function of this number pair. By making use of elementary symmetry and consistency conditions, and without assuming that these real number pairs have any other algebraic structure, we show that these pairs must be manipulated according to the rules of complex arithmetic. We demonstrate that these complex numbers combine according to Feynman's sum and product rules, with the modulus-squared yielding the probability of a sequence of outcomes.

  18. Complex systems: physics beyond physics

    CERN Document Server

    Holovatch, Yurij; Thurner, Stefan

    2016-01-01

    Complex systems are characterized by specific time-dependent interactions among their many constituents. As a consequence they often manifest rich, non-trivial and unexpected behavior. Examples arise both in the physical and non-physical world. The study of complex systems forms a new interdisciplinary research area that cuts across physics, biology, ecology, economics, sociology, and the humanities. In this paper we review the essence of complex systems from a physicist's point of view, and try to clarify what makes them conceptually different from systems that are traditionally studied in physics. Our goal is to demonstrate how the dynamics of such systems may be conceptualized in quantitative and predictive terms by extending notions from statistical physics and how they can often be captured in a framework of co-evolving multiplex network structures. We mention three areas of complex-systems science that are currently studied extensively, the science of cities, dynamics of societies, and the representatio...

  19. Machining of Complex Sculptured Surfaces

    CERN Document Server

    2012-01-01

    The machining of complex sculptured surfaces is a global technological topic in modern manufacturing with relevance in both industrialized and emerging in countries particularly within the moulds and dies sector whose applications include highly technological industries such as the automotive and aircraft industry. Machining of Complex Sculptured Surfaces considers new approaches to the manufacture of moulds and dies within these industries. The traditional technology employed in the manufacture of moulds and dies combined conventional milling and electro-discharge machining (EDM) but this has been replaced with  high-speed milling (HSM) which has been applied in roughing, semi-finishing and finishing of moulds and dies with great success. Machining of Complex Sculptured Surfaces provides recent information on machining of complex sculptured surfaces including modern CAM systems and process planning for three and five axis machining as well as explanations of the advantages of HSM over traditional methods ra...

  20. Making the Tent Function Complex

    Science.gov (United States)

    Sprows, David J.

    2010-01-01

    This note can be used to illustrate to the student such concepts as periodicity in the complex plane. The basic construction makes use of the Tent function which requires only that the student have some working knowledge of binary arithmetic.