400 research outputs found

    Ontogeny of synaptophysin and synaptoporin in the central nervous system

    Get PDF
    The expression of the synaptic vesicle antigens synaptophysin (SY) and synaptoporin (SO) was studied in the rat striatum, which contains a nearly homogeneous population of GABAergic neurons. In situ hybridization revealed high levels of SY transcripts in the striatal anlage from embryonic day (E) 14 until birth. In contrast. SO hybridization signals were low, and no immunoreactive cell bodies were detected at these stages of development. At E 14, SY-immunoreactivity was restricted to perikarya. In later prenatal stages of development SY-immunoreactivity appeared in puncta (identified as terminals containing immunostained synaptic vesicles), fibers, thick fiber bundles and ‘patches’. In postnatal and adult animals, perikarya of striatal neurons exhibited immunoreaction for SO; ultrastructurally SO antigen was found in the Golgi apparatus and in multivesicular bodies. SO-positive boutons were rare in the striatum. In the neuropil, numerous presynaptic terminals positive for SY were observed. Our data indicate that the expression of synaptic vesicle proteins in GABAergic neurons of the striatum is developmentally regulated. Whereas SY is prevalent during embryonic development, SO is the major synaptic vesicle antigen expressed postnatally by striatal neurons which project to the globus pallidus and the substantia nigra. In contrast synapses of striatal afferents (predominantly from cortex, thalamus and substantia nigra) contain SY

    The novel mu-opioid antagonist, GSK1521498, reduces ethanol consumption in C57BL/6J mice.

    Get PDF
    RATIONALE Using the drinking-in-the-dark (DID) model, we compared the effects of a novel mu-opioid receptor antagonist, GSK1521498, with naltrexone, a licensed treatment of alcohol dependence, on ethanol consumption in mice. OBJECTIVE We test the ability of GSK1521498 to reduce alcohol consumption and compare its intrinsic efficacy to that of naltrexone by comparing the two drugs at doses matched for equivalent receptor occupancy. METHODS Thirty-six C57BL/6J mice were tested in a DID procedure. In 2-day cycles, animals experienced one baseline, injection-free session, and one test session when they received two injections, one of test drug and one placebo. All animals received GSK1521498 (0, 0.1, 1 and 3 mg/kg, i.p., 30 min pre-treatment) and naltrexone (0, 0.1, 1 and 3 mg/kg, s.c. 10 min pre-treatment) in a cross-over design. Receptor occupancies following the same doses were determined ex vivo in separate groups by autoradiography, using [3H]DAMGO. Binding in the region of interest was measured integrally by computer-assisted microdensitometry and corrected for non-specific binding. RESULTS Both GSK1521498 and naltrexone dose-dependently decreased ethanol consumption. When drug doses were matched for 70-75 % receptor occupancy, GSK1521498 3 mg/kg, i.p., caused a 2.5-fold greater reduction in alcohol consumption than naltrexone 0.1 mg/kg, s.c. Both GSK1521498 and naltrexone significantly reduced sucrose consumption at a dose of 1 mg/kg but not 0.1 mg/kg. In a test of conditioned taste aversion, GSK1521498 (3 mg/kg) reduced sucrose consumption 24 h following exposure to a conditioning injection. CONCLUSIONS Both opioid receptor antagonists reduced alcohol consumption but GK1521498 has higher intrinsic efficacy than naltrexone

    Fear memory modulation by incentive down and up-shifts

    Get PDF
    Research on retrieval-induced malleability of maladaptive emotional memories has been mostly focused on the effect of drugs and extinction (i.e. post-retrieval extinction). Only a few studies addressed post-retrieval appetitive-aversive interactions. Due to the relevance that the understanding of the interactions between memory content and appetitive or aversive states under retrieval circumstances has for translational research, here we explored the relation between fear (i.e. contextual fear conditioning) and sucrose concentration down (32–4%) or up-shifts (4–32%). These have been reported as methods to induce aversive or appetitive internal states, respectively. We observed that fear expression is differentially susceptible to incentive contrast manipulations depending on the memory stage: acquisition, mere retrieval or retrieval-induced memory malleability. After fear acquisition, freezing behavior and incentive shift direction followed an inverse relation, that is: up-shift decreased fear responding and down-shift increased it. However, freezing behavior remained unaltered when incentive contrast was absent, regardless of the sucrose concentration employed (4–4% and 32–32%). When incentive shifts occurred after mere-retrieval, both negative and positive incentive shifts resulted in increased freezing behavior. Strikingly, this effect was unrelated to the nature of the incentive contrast (either positive or negative), occurring only when animals had no previous experience with the shifted solution. On the other hand, when fear retrieval led to memory malleability, up-shifts in sucrose concentration dampened freezing behavior as much as unshifted controls, whilst down-shift left freezing unaltered. Freezing facilitation was finally achieved after retrieval-induced memory malleability only after prior sampling of the down-shifted solution (i.e. 4% SUC). These results reveal a complex pattern of interactions between memory retrieval and incentive shift-induced internal states

    Guidelines for incorporating scientific knowledge and practice on rare diseases into higher education: neuronal ceroid lipofuscinoses as a model disorder model disorder.

    Get PDF
    This article addresses the educational issues associated with rare diseases (RD) and in particular the Neuronal Ceroid Lipofuscinoses (NCLs, or CLN diseases) in the curricula of Health Sciences and Professional's Training Programs. Our aim is to develop guidelines for improving scientific knowledge and practice in higher education and continuous learning programs. Rare diseases (RD) are collectively common in the general populationwith 1 in 17 people affected by a RDin their lifetime. Inherited defects in genes involved in metabolism are the commonest group of RD with over 8000 known inborn errors of metabolism. The majority of these diseases are neurodegenerative including the NCLs. Any professional training program on NCL must take into account the medical, social and economic burdens related to RDs. To address these challenges and find solutions to themit is necessary that individuals in the government and administrative authorities, academia, teaching hospitals and medical schools, the pharmaceutical industry, investment community and patient advocacy groups all work together to achieve these goals. The logistical issues of including RD lectures in university curricula and in continuing medical education should reflect its complex nature. To evaluate the state of education in the RD field, a summary should be periodically up dated in order to assess the progress achieved in each country that signed up to the international conventions addressing RD issues in society. It is anticipated that auditing current practice will lead to higher standards and provide a framework for those educators involved in establishing RD teaching programs world-wide.publishedVersio

    ANÁLISE COMPARATIVA DA PRODUTIVIDADE DOS PARES ORIENTADOR-ORIENTADO EM CIÊNCIA DA COMPUTAÇÃO

    Get PDF
    The increasing involvement of graduate students in scientific communication has been the subject of studies in many countries that have been discussing the role of doctoral studies in the research career. In this article we are interested on the study of the academic relationship between the advisor and the advisee for a group of PhD pairs in the Computer Science area, with curricula registered in the Lattes Platform. We analyze the main characteristics of the group and their coauthor relationships. In terms of co-authorship: (i) we observe that the duration that is established between advisor and advisee can extrapolate the formal period of supervision, and (ii) we show that the duration of the collaboration is correlated with both the number of articles published by the advisee and the ones published by the advisor. In this work we also present the advisee profile for researchers that worked in some of the graduate courses in Computer Science in Brazil in the triennium 2007-2009.A crescente participação dos pós-graduandos na comunicação científica das diversas áreas da ciência tem sido tema de estudos em diversos países que vêm discutindo o papel do doutoramento na carreira de pesquisa. Neste artigo é estudada a relação acadêmica temporal existente entre o aluno orientado e seu orientador para o conjunto de pares de doutores da área de Ciência da Computação com currículos cadastrados na plataforma Lattes. Analisamos as principais características do grupo e suas relações de coautoria. Em termos de coautoria: (i) observamos que o tempo de duração da parceria que se estabelece entre orientador e orientado pode extrapolar o período formal de orientação e (ii) mostramos que a duração do tempo de colaboração correlaciona-se com o número de artigos em periódicos publicados pelo orientado e o número de artigos publicados pelo orientador. Neste trabalho também apresentamos o perfil dos orientados para pesquisadores que atuaram como docentes de algum dos cursos de pós-graduação em Ciência da Computação no Brasil no triênio 2007-2009
    corecore