892 resultados para virus causing behavioral changes
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Systemic administration of cannabidiol (CBD) attenuates cardiovascular and behavioral changes induced by re-exposure to a context that had been previously paired with footshocks. Previous results from our group using cFos immunohistochemistry suggested that the bed nucleus of the stria terminalis (BNST) is involved in this effect. The mechanisms of CBD effects are still poorly understood, but could involve 5-HT1A receptor activation. Thus, the present work investigated if CBD administration into the BNST would attenuate the expression of contextual fear conditioning and if this effect would involve the activation of 5-HT1A receptors. Male Wistar rats with cannulae bilaterally implanted into the BNST were submitted to a 10 min conditioning session (six footshocks, 1.5 mA/3 s). Twenty-four hours later freezing and cardiovascular responses (mean arterial pressure and heart rate) to the conditioning box were measured for 10 min. CBD (15, 30 or 60 nmol) or vehicle was administered 10 min before the re-exposure to the aversive context. The second experiment was similar to the first one except that animals received microinjections of the 5-HT1A receptor antagonist WAY100635 (0.37 nmol) 5 min before CBD (30 nmol) treatment. The results showed that CBD (30 and 60 nmol) treatment significantly reduced the freezing and attenuated the cardiovascular responses induced by re-exposure to the aversive context. Moreover, WAY100635 by itself did not change the cardiovascular and behavioral response to context, but blocked the CBD effects. These results suggest that CBD can act in the BNST to attenuate aversive conditioning responses and this effect seems to involve 5-HT1A receptor-mediated neurotransmission.
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The ventrolateral caudoputamen (VLCP) is well known to participate in the control of orofacial movements and forepaw usage accompanying feeding behavior. Previous studies from our laboratory have shown that insect hunting is associated with a distinct Fos up-regulation in the VLCP at intermediate rostro-caudal levels. Moreover, using the reversible blockade with lidocaine, we have previously suggested that the VLCP implements the stereotyped actions seen during prey capture and handling, and may influence the motivational drive to start attacking the roaches, as well. However, considering that (1) lidocaine suppresses action potentials not only in neurons, but also in fibers-of-passage, rendering the observed behavioral effect not specific to the ventrolateral caudoputamen; (2) the short lidocaine-induced inactivation period had left a relatively narrow window to observe the behavioral changes; and (3) that the restriction stress to inject the drug could have also disturbed hunting behavior, in the present study, we have examined the role of the VLCP in predatory hunting by placing bilateral NMDA lesions three weeks previous to the behavior testing. We were able to confirm that the VLCP serves to implement the stereotyped sequence of actions seen during prey capture and handling, but the study did not confirm its role in influencing the motivational drive to hunt. Together with other studies from our group, the present work serves as an important piece of information that helps to reveal the neural systems underlying predatory hunting. (C) 2011 Elsevier Inc. All rights reserved.
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Ein funktionelles Zusammenspiel von LRP1, einem Mitglied der LDL-Rezeptorfamilie, mit dem NMDA-Rezeptor, einem Glutamat Rezeptor, wurde durch die Interaktion beider Proteine sowie eine tPa-vermittelte, LRP1-abhängige Signalübertragung durch den NMDA-Rezeptor belegt. Darüber hinaus zeigen Mäuse mit einem konditionellen neuronalen knock-out des Lrp1 Gens Verhaltensänderungen, die mit einer beeinträchtigten Signalübertragung durch NMDA-Rezeptoren assoziiert werden könnten. Die genaue Rolle von LRP1 in der NMDA-Rezeptor-Funktion bleibt allerdings noch unklar. In der vorliegenden Arbeit wurde die Rolle von LRP1 bei der Expression der NR2B-Untereinheit des NMDA-Rezeptors an der Zelloberfläche primärer kortikaler Neurone untersucht. Zu diesem Zweck wurde die knock-in Mauslinie LRP1ΔNPxY2, die sich durch eine Alanin Substitution im NPxY2 Motiv des LRP1 auszeichnet, eingesetzt. rnEs konnte gezeigt werden, dass diese knock-in Mutation in einer erhöhten Expression von LRP1 und der NMDA-Rezeptoruntereinheiten NR1 und NR2B an der Zelloberfläche primärer kortikaler Neurone resultiert. Der Effekt konnte durch eine reduzierte Endozytoserate von LRP1 und der NR1-und NR2B-Untereinheiten in primären LRP1ΔNPxY2 Neuronen erklärt werden. Darüber hinaus wurde ein verändertes Phosphorylierungsmuster der Internalisierungssignale der NR2B-Rezeptoruntereinheit Serin S1480 und Tyrosin Y1472 an der Zelloberfläche primärer LRP1ΔNPxY2 Neurone detektiert. Die verantwortlichen Kinasen Fyn und Kasein-Kinase II sind allerdings in LRP1ΔNPxY2 Neuronen im Vergleich zu den Wildtyp-Kontrollen nicht abweichend reguliert. In den Co-Immunopräzipitationsexperimenten wurde gezeigt, dass die Bindung von LRP1 mit NR2B durch die Phosphorylierung reguliert wird und dieser Regulationsmechanismus in LRP1ΔNPxY2 Neuronen beeinträchtigt ist. Dies resultiert in einer stärkeren Bindung von NR2B-Rezeptoruntereinheit an LRP1. Aufgrund reduzierter Internalisierungsraten von LRP1 in LRP1ΔNPxY2 Neuronen führt dieser Umstand zu einer Akkumulation beider Rezeptorproteine an der Zelloberfläche. Schließlich wurden die NMDA-Rezeptor-assoziierten Verhaltensänderungen wie die Hyperaktivität und die Defizite im direkten und umgekehrten räumlichen Lernvermögen in den LRP1ΔNPxY2 Tieren nachgewiesen. Zusammengefasst, demonstrieren diese Ergebnisse, dass LRP1 eine kritische Rolle in der Regulierung der NR2B-Expression an der Zelloberfläche spielt.
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In einem Ökosystem beeinflussen sich Tiere gegenseitig in erster Linie durch direkte Interaktionen. Ihr Verhalten kann aber auch indirekt durch chemotaktile Stoffe die andere Tiere in der Umwelt hinterlassen beeinflusst werden. Vergleichbar zu direkten Interaktionen können indirekt ausgelöste Verhaltensänderungen einen starken Einfluss auf Populationsdynamiken und Gemeinschaftsstrukturen eines Ökosystems haben. Obwohl das daran gehegte Interesse der Ökologen in den letzten Jahrzenten stark gestiegen ist, fehlen immer noch Studien, welche über mehrere Arten hinweg versuchen die übergreifende Relevanz von chemotaktilen Stoffen herauszufinden. Im Rahmen meiner Doktorarbeit untersuchte ich daher wie sich mehrere mitteleuropäische Arthropodenarten, abhängig von deren interspezifischen Räuber-Beute- und Konkurrenzbeziehungen, mittels chemotaktiler Stoffe beeinflussen können. Mithilfe unterschiedlicher Verhaltensversuche konnte ich empirisch nachweisen, dass verschiedene Arthropoden chemotaktile Stoffe zu ihrem eigenen Vorteil nutzen können. Außerdem zeigen meine Ergebnisse, dass die Verhaltensänderungen artspezifisch und abhängig von den jeweiligen Lebenszyklen und den damit verbundenen Eigenschaften (z.B. Körpergröße, Häufigkeit oder Rangordnung) der beteiligten Arten sind. Ich vermute daher, dass Arthropoden chemotaktile Stoffe ihrer Gegenspieler wahrnehmen und interpretieren können. Eine Verhaltensänderung scheint jedoch nur dann statt zu finden wenn ein Nichtreagieren starke Fitnesskosten mit sich führen würde. Zusammenfassend zeigen die Ergebnisse meiner Doktorarbeit, wie wichtig es ist, die Bedeutung von chemotaktilen Stoffen innerhalb vieler Arten einer Gemeinschaft zu testen, um die den Verhaltensänderungen zugrundeliegenden Ursachen identifizieren zu können. Dies wiederum stellt die Grundlage, um die ökologische Relevanz von chemotaktilen Stoffen und deren mögliche Effekte auf Ökosystemfunktionen besser zu verstehen.
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A multimodal approach is state-of-the art for effective treatment of functional gastrointestinal disorders (FGD) like irritable bowel syndrome and functional dyspepsia. Based on the now established view that the pathogenesis of FGD is multicausal, evidence-based therapeutic options comprise education about the nature of the disorder, dietary modifications, relaxation techniques, behavioral changes, and pharmacological treatments. These therapies are variously combined depending on the severity of the FGD and the individual needs of the patient. Our overview portrays the options for the therapy of FGD and proposes that these are best provided by an interdisciplinary team of primary care physicians, gastroenterologists, and psychosomatic medicine specialists.
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Autoimmune and infectious diseases are associated with behavioral changes referred to as sickness behavior syndrome (SBS). In autoimmunity, the generation of anti-self T lymphocytes and autoantibodies critically involves binding of CD40 ligand on T-cells to its receptor CD40 on B-cells, dendritic cells and macrophages. Activation of CD40 leads to production of proinflammatory cytokines and, as shown here, induces SBS. Here we report that these behavioral changes depend on the expression of tumor necrosis factor alpha receptor 1 (TNFR1), but not on interleukin-1 receptor 1 or interleukin-6. Moreover, the intensity of SBS correlates with suppression of E-box controlled clock genes, including Dbp, and upregulation of Bmal1. However, the absence of TNFR1 does not interfere with the development of SBS and dysregulation of clock genes in mice treated with lipopolysaccharide. Thus, our results suggest that TNFR1 mediates SBS and dysregulation of clock genes in autoimmune diseases.
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Disturbances in reward processing have been implicated in bulimia nervosa (BN). Abnormalities in processing reward-related stimuli might be linked to dysfunctions of the catecholaminergic neurotransmitter system, but findings have been inconclusive. A powerful way to investigate the relationship between catecholaminergic function and behavior is to examine behavioral changes in response to experimental catecholamine depletion (CD). The purpose of this study was to uncover putative catecholaminergic dysfunction in remitted subjects with BN who performed a reinforcement-learning task after CD. CD was achieved by oral alpha-methyl-para-tyrosine (AMPT) in 19 unmedicated female subjects with remitted BN (rBN) and 28 demographically matched healthy female controls (HC). Sham depletion administered identical capsules containing diphenhydramine. The study design consisted of a randomized, double-blind, placebo-controlled crossover, single-site experimental trial. The main outcome measures were reward learning in a probabilistic reward task analyzed using signal-detection theory. Secondary outcome measures included self-report assessments, including the Eating Disorder Examination-Questionnaire. Relative to healthy controls, rBN subjects were characterized by blunted reward learning in the AMPT-but not in placebo-condition. Highlighting the specificity of these findings, groups did not differ in their ability to perceptually distinguish between stimuli. Increased CD-induced anhedonic (but not eating disorder) symptoms were associated with a reduced response bias toward a more frequently rewarded stimulus. In conclusion, under CD, rBN subjects showed reduced reward learning compared with healthy control subjects. These deficits uncover disturbance of the central reward processing systems in rBN related to altered brain catecholamine levels, which might reflect a trait-like deficit increasing vulnerability to BN.
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Treelines are expected to rise to higher elevations with climate warming; the rate and extent however are still largely unknown. Here we present the first multi-proxy palaeoecological study from the treeline in the Northwestern Swiss Alps that covers the entire Holocene. We reconstructed climate, fire and vegetation dynamics at Iffigsee, an alpine lake at 2,065 m a.s.l., by using seismic sedimentary surveys, loss on ignition, visible spectrum reflectance spectroscopy, pollen, spore, macrofossil and charcoal analyses. Afforestation with Larix decidua and tree Betula (probably B. pendula) started at ~9,800 cal. b.p., more than 1,000 years later than at similar elevations in the Central and Southern Alps, indicating cooler temperatures and/or a high seasonality. Highest biomass production and forest position of ~2,100–2,300 m a.s.l. are inferred during the Holocene Thermal Maximum from 7,000 to 5,000 cal. b.p. With the onset of pastoralism and transhumance at 6,800–6,500 cal. b.p., human impact became an important factor in the vegetation dynamics at Iffigsee. This early evidence of pastoralism is documented by the presence of grazing indicators (pollen, spores), as well as a wealth of archaeological finds at the nearby mountain pass of Schnidejoch. Human and fire impact during the Neolithic and Bronze Ages led to the establishment of pastures and facilitated the expansion of Picea abies and Alnus viridis. We expect that in mountain areas with land abandonment, the treeline will react quickly to future climate warming by shifting to higher elevations, causing drastic changes in species distribution and composition as well as severe biodiversity losses.
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This paper applies a policy analysis approach to the question of how to effectively regulate micropollution in a sustainable manner. Micropollution is a complex policy problem characterized by a huge number and diversity of chemical substances, as well as various entry paths into the aquatic environment. It challenges traditional water quality management by calling for new technologies in wastewater treatment and behavioral changes in industry, agriculture and civil society. In light of such challenges, the question arises as to how to regulate such a complex phenomenon to ensure water quality is maintained in the future? What can we learn from past experiences in water quality regulation? To answer these questions, policy analysis strongly focuses on the design and choice of policy instruments and the mix of such measures. In this paper, we review instruments commonly used in past water quality regulation. We evaluate their ability to respond to the characteristics of a more recent water quality problem, i.e., micropollution, in a sustainable way. This way, we develop a new framework that integrates both the problem dimension (i.e., causes and effects of a problem) as well as the sustainability dimension (e.g., long-term, cross-sectoral and multi-level) to assess which policy instruments are best suited to regulate micropollution. We thus conclude that sustainability criteria help to identify an appropriate instrument mix of end-of-pipe and source-directed measures to reduce aquatic micropollution.
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BACKGROUND Hand eczema has a high impact on patients' quality of life. The treatment focuses on improving skin barrier function. OBJECTIVES To evaluate the effects and acceptance of a novel educational program for patients with hand eczema. METHODS Retrospectively, the records of 36 patients who attended the prevention program and follow-up visits were analyzed. Physician global assessment (PGA) scores, acceptance and behavioral changes were assessed. RESULTS In 67% of patients, an improvement of the hand eczema could be attributed to the effects of our educational program. The mean PGA score significantly decreased from 3 before education to 2.2 during follow-up. Behavioral changes in both skin care and protection were reported in 81 and 86%, respectively. CONCLUSIONs: Our educational program had a positive effect on clinical outcome as well as adherence to skin care and protection measures. Its integration in a hand eczema clinic was feasible and well accepted by the patients.
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Dieser Fallbericht beschreibt drei Katzenwelpen mit Verdacht auf Doramectin-Intoxikation. Ein Wurf von insgesamt 7 Katzenwelpen wurde mit Doramectin behandelt, woraufhin drei Welpen neurologische Symptome entwickeltena Ein Welpe zeigte leichte Apathie und Zittern, ein weiterer zusätzlich Verhaltensänderungen und epileptiforme Anfälle, die mit Diazepam behandelt werden mussten. Beide Welpen erholten sich vollständig. Ein dritter Welpe wurde 3 Tage nach Doramectin-Gabe stuporös vorgestellt und zeigte im weiteren Verlauf Verhaltensänderungen wie Aggressivität, Hyperästhesie, Tremor und epileptiforme Anfälle. Er verstarb 36 Stunden nach Vorstellung. Bei der histopathologischen Untersuchung des Gehirns konnten ein zytotoxisches Ödem und Polioenzephalomalazie festgestellt werden. Die Doramectin-Dosis beim verstorbenen Welpen betrug 380 μg/kg.
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The paper addresses the question of which factors drive the formation of policy preferences when there are remaining uncertainties about the causes and effects of the problem at stake. To answer this question we examine policy preferences reducing aquatic micropollutants, a specific case of water protection policy and different actor groups (e.g. state, science, target groups). Here, we contrast two types of policy preferences: a) preventive or source-directed policies, which mitigate pollution in order to avoid contact with water; and b) reactive or end-of-pipe policies, which filter water already contaminated by pollutants. In a second step, we analyze the drivers for actors’ policy preferences by focusing on three sets of explanations, i.e. participation, affectedness and international collaborations. The analysis of our survey data, qualitative interviews and regression analysis of the Swiss political elite show that participation in the policy-making process leads to knowledge exchange and reduces uncertainties about the policy problem, which promotes preferences for preventive policies. Likewise, actors who are affected by the consequences of micropollutants, such as consumer or environmental associations, opt for anticipatory policies. Interestingly, we find that uncertainties about the effectiveness of preventive policies can promote preferences for end-of-pipe policies. While preventive measures often rely on (uncertain) behavioral changes of target groups, reactive policies are more reliable when it comes to fulfilling defined policy goals. Finally, we find that in a transboundary water management context, actors with international collaborations prefer policies that produce immediate and reliable outcomes.
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The evolution of porosity due to dissolution/precipitation processes of minerals and the associated change of transport parameters are of major interest for natural geological environments and engineered underground structures. We designed a reproducible and fast to conduct 2D experiment, which is flexible enough to investigate several process couplings implemented in the numerical code OpenGeosys-GEM (OGS-GEM). We investigated advective-diffusive transport of solutes, effect of liquid phase density on advective transport, and kinetically controlled dissolution/precipitation reactions causing porosity changes. In addition, the system allowed to investigate the influence of microscopic (pore scale) processes on macroscopic (continuum scale) transport. A Plexiglas tank of dimension 10 × 10 cm was filled with a 1 cm thick reactive layer consisting of a bimodal grain size distribution of celestite (SrSO4) crystals, sandwiched between two layers of sand. A barium chloride solution was injected into the tank causing an asymmetric flow field to develop. As the barium chloride reached the celestite region, dissolution of celestite was initiated and barite precipitated. Due to the higher molar volume of barite, its precipitation caused a porosity decrease and thus also a decrease in the permeability of the porous medium. The change of flow in space and time was observed via injection of conservative tracers and analysis of effluents. In addition, an extensive post-mortem analysis of the reacted medium was conducted. We could successfully model the flow (with and without fluid density effects) and the transport of conservative tracers with a (continuum scale) reactive transport model. The prediction of the reactive experiments initially failed. Only the inclusion of information from post-mortem analysis gave a satisfactory match for the case where the flow field changed due to dissolution/precipitation reactions. We concentrated on the refinement of post-mortem analysis and the investigation of the dissolution/precipitation mechanisms at the pore scale. Our analytical techniques combined scanning electron microscopy (SEM) and synchrotron X-ray micro-diffraction/micro-fluorescence performed at the XAS beamline (Swiss Light Source). The newly formed phases include an epitaxial growth of barite micro-crystals on large celestite crystals (epitaxial growth) and a nano-crystalline barite phase (resulting from the dissolution of small celestite crystals) with residues of celestite crystals in the pore interstices. Classical nucleation theory, using well-established and estimated parameters describing barite precipitation, was applied to explain the mineralogical changes occurring in our system. Our pore scale investigation showed limits of the continuum scale reactive transport model. Although kinetic effects were implemented by fixing two distinct rates for the dissolution of large and small celestite crystals, instantaneous precipitation of barite was assumed as soon as oversaturation occurred. Precipitation kinetics, passivation of large celestite crystals and metastability of supersaturated solutions, i.e. the conditions under which nucleation cannot occur despite high supersaturation, were neglected. These results will be used to develop a pore scale model that describes precipitation and dissolution of crystals at the pore scale for various transport and chemical conditions. Pore scale modelling can be used to parameterize constitutive equations to introduce pore-scale corrections into macroscopic (continuum) reactive transport models. Microscopic understanding of the system is fundamental for modelling from the pore to the continuum scale.
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Objective: In humans and other animals, open, expansive postures (compared to contracted postures) are evolutionary developed expressions of power and have been shown to cause neuroendocrine and behavioral changes (Carney, Cuddy, & Yap, 2010). In the present study we aimed to investigate whether power postures have a bearing on the participant’s facial appearance and whether others are able to distinguish faces after “high power posing” from faces after “low power posing”. Methods: 16 models were photographed 4-5 minutes after having adopted high and low power postures. Two different high power and two different low power postures were held for 2 minutes each. Power-posing sessions were performed on two consecutive days. High and low power photographs of each model were paired and an independent sample of 100 participants were asked to pick the more dominant and the more likeable face of each pair. Results: Photographs that were taken after adopting high power postures were chosen significantly more often as being more dominant looking. There was no preference when asked to choose the more likeable photograph (chance level). A further independent sample rated each photograph for head tilt, making it unlikely that dominance ratings were caused merely by the posture of the head. Consistently, facial width-to-height ratio did not differ between faces after high and low power posing. Conclusions: Postures associated with high power affect facial appearance, leading to a more dominant looking face. This finding may have implications for everyday life, for instance when a dominant appearance is needed.
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Objective. The purpose of this study was to determine the meaning of personal transformation for twenty women in long term, stable recovery from alcohol abuse; to identify themes or patterns of this recovery, and; to determine the extent to which they experienced the phenomenon of perspective transformation. ^ Method. Volunteers were recruited by advertisement, word of mouth, and through a closed circuit web based broadcast. A descriptive, exploratory study, which analyzed perspective transformation from the standpoint of five action phases, was conducted. Data was collected using in-depth personal interviews and questionnaires. Subjects' responses were analyzed by qualitative methods. Triangulation was performed on the grouped data comparing the interviews to the data produced by the questionnaires. Quantitative analysis of questionnaire items explored behavioral changes experienced before and after alcoholism recovery. ^ Results. Five phases of recovery were identified. Phase I which involved recognition that alcohol was a problem and change might be possible took several years during which 3 major transitions occurred: (1) from often being alienated to having relationships with family and friends; (2) from daily upheavals to eventually a more peaceful existence, and; (3) from denial that alcohol was a problem to acceptance and willingness to change. Recovery was often seen in a spiritual context, which also required ongoing support. During Phase II there was an assessment of self, others, and the environment which revealed a pattern of intense unhappiness and negative feelings toward self and others with a disregard for cultural norms. Phase III revealed a period of desperation as life became unmanageable, but gradual willingness to accept support and guidance and a desire to improve self and help others. This led to improvement of existing role performance and the willingness to try out new roles. In Phase IV there was a pattern of personal growth which included: the establishment of boundaries, setting priorities, a willingness to place others' needs above their own, acceptance of responsibility, and learning to cope without alcohol, often with the use of tools learned in AA. During Phase V, many experienced knowledge of frailties but growing respect for self and others, with an improved ability to function in giving relationships. Implications for Prevention and Recovery: Early education concerning addiction and recovery may play a crucial role in prevention and early recovery, as it did for children of women in this study. Recovery requires persistent effort and organized support. ^