11 research outputs found

    Constraints on the Variations of the Fundamental Couplings

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    We reconsider several current bounds on the variation of the fine-structure constant in models where all gauge and Yukawa couplings vary in an interdependent manner, as would be expected in unified theories. In particular, we re-examine the bounds established by the Oklo reactor from the resonant neutron capture cross-section of 149Sm. By imposing variations in \Lambda_{QCD} and the quark masses, as dictated by unified theories, the corresponding bound on the variation of the fine-structure constant can be improved by about 2 orders of magnitude in such theories. In addition, we consider possible bounds on variations due to their effect on long lived \alpha- and \beta-decay isotopes, particularly 147Sm and 187Re. We obtain a strong constraint on \Delta \alpha / \alpha, comparable to that of Oklo but extending to a higher redshift corresponding to the age of the solar system, from the radioactive life-time of 187Re derived from meteoritic studies. We also analyze the astrophysical consequences of perturbing the decay Q values on bound state \beta-decays operating in the s-process.Comment: 25 pages, latex, 5 eps figure

    Evaluation of neurotransmitters involved in the anxiolytic and panicolytic effect of the aqueous fraction of Paullinia cupana (guaraná) in elevated T maze

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    This study investigated the effects of repeatedly administration of an aqueous fraction of Paullinia cupana Kunth, Sapindaceae (guaraná) seeds (8 mg/kg) on rats submitted to the elevated T-maze, model of generalized anxiety and panic disorders. The selective serotonin reuptake inhibitor paroxetine (3 mg/kg), was used as a positive control. To evaluate possible neurotransmissions involvement, ineffective doses of metergoline (3 mg/kg - non-selective serotonin receptor antagonist), sulpiride (20 mg/kg - non-selective dopaminergic receptor antagonist) or ketamine (0.125 mg/kg - non-selective glutamate receptor antagonist) were acutely administered in association with the aqueous fraction of P. cupana. Both aqueous fraction and paroxetine decrease the inhibitory avoidance latencies of the elevated T-maze, indicating anxiolytic effect and increased one-way escape latencies from the open arm of the elevated T-maze, indicating a panicolytic effect. The pre-treatment with metergoline, sulpiride and ketamine blocked the anxiolytic effect of aqueous fraction. The panicolytic effect of aqueous fraction was blocked by both metergoline and sulpiride. These results show that the serotonergic, dopaminergic and glutamatergic neurotransmission systems are involved in anxiolytic effect promoted by aqueous fraction, whereas only the serotonergic and the dopaminergic neurotransmission systems are involved in the panicolytic effect promoted by aqueous fraction of P. cupana. The effects produced by paroxetine, were blocked only by metergoline, validating this experimental procedure

    Pindolol potentiates the panicolytic effect of paroxetine in the elevated T-maze

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    Aims: The beta-adrenergic and 5-HT(1A) receptor antagonist pindolol has been used in combination with antidepressant drugs, to shorten the time of onset of clinical efficacy and/or increase the proportion of responders in depressive and anxiety disorders. The aim of this study was to examine the interaction between pindolol and the selective serotonin reuptake inhibitor (SSRI), paroxetine in rats submitted to the elevated T-maze (ETM). Main methods: For assessing the drug combination effect, rats were administered with pindolol before paroxetine, using oral or intraperitoneal (i.p.) routes of acute administration, and were submitted to the ETM model. Key findings: The highest dose of pindolol used (15.0 mg/kg, i.p.) increased both inhibitory avoidance and escape latencies in the ETM, probably due to nonspecific motor deficit, since locomotion in a circular arena was also significantly decreased. The highest dose of paroxetine (3.0 mg/kg, i.p.) selectively impaired escape, considered a panicolytic effect. Combination of pindolol (5.0 mg/kg, i.p.) with an ineffective dose of paroxetine (1.5 mg/kg, i.p.) impaired escape, indicating a potentiation of the panicolytic effect of paroxetine. By the oral route, neither paroxetine (3.0 mg/kg) nor pindolol (5.0 mg/kg) alone were effective, but the combination treatment had a marked panicolytic effect, again indicating drug potentiation. Significance: The present results show that the combination of the ineffective doses of pindolol and paroxetine significantly increased escape latency, indicating a selective panicolytic effect. These findings give preclinical support for the use of this drug combination in the treatment of panic disorder (PD). (C) 2010 Elsevier Inc. All rights reserved.CNPq, BrazilFAEP

    alata Dryander and Valeriana officinalis L. in rats

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    Anxiolytic and sedative edative effects of a combined extract of Passiflor

    The panicolytic-like effect of fluoxetine in the elevated T-maze is mediated by serotonin-induced activation of endogenous opioids in the dorsal periaqueductal grey

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    Serotonin (5-HT), opioids and the dorsal periaqueductal grey (DPAG) have been implicated in the pathophysiology of panic disorder. In order to study 5-HT-opioid interaction, the opioid antagonist naloxone was injected either systemically (1 mg/kg, i.p.) or intra-DPAG (0.2 mu g/0.5 mu L) to assess its interference with the effect of chronic fluoxetine (10 mg/kg, i.p., daily for 21 days) or of intra-DPAG 5-HT (8 mu g/0.5 mu L). Drug effects were measured in the one-escape task of the rat elevated T-maze, an animal model of panic. Pretreatment with systemic naloxone antagonized the lengthening of escape latency caused by chronic fluoxetine, considered a panicolytic-like effect that parallels the drug's therapeutic response in the clinics. Pretreatment with naloxone injected intra-DPAG antagonized both the panicolytic effect of chronic fluoxetine as well as that of 5-HT injected intra-DPAG. Neither the performance of the inhibitory avoidance task in the elevated T-maze, a model of generalized anxiety nor locomotion measured in a circular arena was affected by the above drug treatments. These results indicate that the panicolytic effect of fluoxetine is mediated by endogenous opioids that are activated by 5-HT in the DPAG. They also allow reconciliation between the serotonergic and opioidergic hypotheses of panic disorder pathophysiology.CAPESCNPqFundacao de Amparo ao Ensino, Pesquisa e Assistencia do Hospital das Clinicas de Ribeirao Preto (FAEPA

    Violência contra a mulher na rede de atenção básica: o que os enfermeiros sabem sobre o problema? Violence against women in the basic care network: what do nurses know about the problem?

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    OBJETIVOS: descrever o conhecimento dos enfermeiros das Unidades Distritais Básicas de Saúde do município de Ribeirão Preto, SP, Brasil, acerca da violência contra a mulher, particularmente aquela cometida pelo parceiro íntimo. MÉTODOS: estudo quantitativo, transversal e descritivo. Participaram 51 enfermeiros, extraídos de um estudo maior com 221 profissionais de saúde. Os dados foram coletados por meio de questionário que investigava o conhecimento em relação à violência cometida contra as mulheres. RESULTADOS: os enfermeiros acertaram de 76% a 90,2% das questões sobre definição de violência de gênero e 78% obtiveram altos escores em questões sobre epidemiologia da violência; no entanto, 70,6% demonstraram desconhecer sua epidemiologia nos serviços de pré-natal. 83,7% dos enfermeiros demonstraram bom conhecimento sobre como abordar as vítimas para obter a revelação da violência ocorrida e 52% demonstraram conhecimento elevado sobre o manejo dos casos. CONCLUSÕES: os enfermeiros conhecem bem a definição de violência, têm conhecimentos sobre o manejo de casos, a necessidade de notificação e encaminhamentos de casos em situação de risco. Entretanto, desconhecem características epidemiológicas importantes da violência contra a mulher, o que pode ser uma barreira para a atuação dos enfermeiros no atendimento a mulheres em situação de risco, principalmente durante a atenção no pré-natal.<br>OBJECTIVES: to outline what nurses from the District Basic Care Units of the municipality of Ribeirão Preto, in the Brazilian State of São Paulo, know about violence against women, especially that perpetrated by an intimate partner. METHODS: a quantitative, cross-sectional, descriptive study was carried out with 51 nurses drawn from a larger study of 221 health workers. The data were collected using a questionnaire that asked about their knowledge regarding violence against women. RESULTS: the nurses correctly answered 76% to 90.2% of the questions on the definition of gender violence and 78% obtained high scores on questions relating to the epidemiology of violence. However, 70.6% showed no knowledge of the epidemiology of violence in prenatal services. 83.7% of the nurses showed good knowledge of how to deal with victims to get them to report the abuse and 52% showed a good knowledge of case management. CONCLUSIONS: nurses are well aware of what violence is and have knowledge about how to manage cases and the need to report abuse and refer women who are at risk. However, they are unaware of important epidemiological features of violence against women, which may pose an obstacle to their ability to attend women at risk, especially during prenatal care
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