1000 resultados para 159.953
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Early-life environmental events that disrupt the mother-pup relationship may induce profound long-lasting changes on several behavioral and neuroendocrine systems. The neonatal handling procedure, which involves repeated brief maternal separations followed by experimental manipulations, reduces sexual behavior and induces anovulatory estrous cycles in female rats. On the afternoon of proestrus, neonatally handled females show a reduced surge of luteinizing hormone (LH) and an increased content of gonadotropin-releasing hormone in the medial preoptic area (MPOA). In order to detect the possible causes for the reduced ovulation and sexual behavior, the present study aimed to analyze the effects of neonatal handling on noradrenaline (NA) and nitric oxide (NO) levels in the MPOA on the afternoon of proestrus. Neonatal handling reduced MHPG (NA metabolite) levels and MHPG/NA ratio in the MPOA, indicating decreased NAergic activity. Additionally, neonatal handling decreased NO levels, as measured by the metabolites (NO x), nitrite and nitrate in the same period. We may conclude that the neonatal handling procedure decreased activity of the NAergic and NOergic systems in the MPOA during proestrus, which is involved in the control of LH and FSH secretion, and this may possibly explain the anovulatory estrous cycles and reduced sexual behavior of the neonatally handled female rats. Copyright (c) 2007 S. Karger AG, Basel.
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Chronic L-DOPA pharmacotherapy in Parkinson`s disease is often, accompanied by the development of abnormal and excessive movements known as L-DOPA-induced dyskinesia. Rats with 6-hydroxydopamine lesion of dopaminergic neurons chronically treated with L-DOPA develop a rodent analog of this dyskinesia characterized by severe axial, limb, locomotor and orofacial abnormal involuntary movements. While the mechanisms by which these effects occur are not clear, they may involve the nitric oxide system. In the present study we investigate if nitric oxide synthase inhibitors can prevent dyskinesias induced by repeated administration Of L-DOPA in rats with unilateral 6-hydroxydopamine lesion. Chronic L-DOPA (high fixed dose, 100 mg/kg; low escalating dose, 10-30 mg/kg) treatment induced progressive dyskinesia changes. Two nitric oxide synthase inhibitors, 7-nitroindazole (1-30 mg/kg) and NG-nitro-L-arginine (50 mg/kg), given 30 min before L-DOPA, attenuate dyskinesia. 7-Nitroindazolee also improved motor performance of these animals in the rota-rod test. These results suggest the possibility that nitric oxide synthase inhibitors may be useful to treat L-DOPA.-Induced dyskinesia. (C) 2009 IBRO. Published by Elsevier Ltd. All rights reserved.
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Background: Nitric oxide (NO) is a major regulator of cardiovascular homeostasis and has anti-atherogenic properties. Reduced NO formation is associated with endothelial dysfunction and with cardiovascular risk factors. Although NO downregulates the expression and activity of the pro-atherogenic enzyme matrix metalloproteinase-9 (MMP-9), no previous clinical study has examined whether endogenous NO formation is inversely associated with the circulating levels of pro-MMP-9, which are associated with cardiovascular events. We examined this hypothesis in 175 healthy male subjects who were non-smokers. Methods: To assess NO bioavailability, the plasma concentrations of nitrite, nitrate, and cGMP were determined using an ozone-based chemiluminescence assay and an enzyme immunoassay. Pro-MMP-9 and pro-MMP-2 levels were measured in plasma samples by gelatin zymography. Results: We found significant negative correlations between pro-MMP-9 levels and plasma nitrite (P=0.035, rs=-0.159), nitrate (P=0.040, rs=-0.158), and cGMP (P=0.011, rs=-0.189) concentrations. However, no significant correlations were found between pro-MMP-2 levels and the plasma concentrations of markers of NO bioavailability (all P>0.05). Conclusions: There is an inverse relationship between markers of NO formation and plasma MMP-9 levels. This finding may shed some light on the possible mechanisms involved in the increased cardiovascular risk of apparently healthy subjects with low NO bioavailability or high circulating levels of pro-MMP-9. (C) 2008 Elsevier B.V. All rights reserved.
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Statins exert anti-inflammatory effects and downregulate matrix metalloproteinases (MMPs) expression, thus contributing to restore cardiovascular homeostasis in cardiovascular diseases. We aimed at comparing the effects of different statins (simvastatin, atorvastatin, and pravastatin) on MMP-2, MMP-9, tissue inhibitors of metalloproteinases (TIMP)-1, TIMP-2, and MMP-9/TIMP-1 and MMP-2/TIMP-2 ratios released by human umbilical vein endothelial cells (HUVEC) stimulated by phorbol myristate acetate (PMA). HUVECs were incubated with statins (0.1-10 mu M) for 12 h before stimulation with PMA 100 nM. Monolayers were used to perform cell viability assays and the supernatants were collected to determine MMPs and TIMPs levels by gelatin zymography and/or enzyme immunoassay. While treatment with PMA increased MMP-9 and TIMP-1 levels (by 556% and 159%, respectively; both P < 0.05), it exerted no effects on MMP-2 and TIMP-2 levels. Simvastatin and atorvastatin, but not pravastatin, attenuated PMA-induced increases in MMP-9 levels (P < 0.05). Only atorvastatin decreased baseline MMP-2 levels significantly (P < 0.05). We found no effects on TIMP-2 levels. Simvastatin and atorvastatin, but not pravastatin, decreased MMP-9/TIMP-1 ratio significantly (both P < 0.05), whereas atorvastatin and pravastatin, but not simvastatin, decreased MMP-2/TIMP-2 ratio significantly (both P < 0.05). Our data support the notion that statins with different physicochemical features exert variable effects on MMP/TIMP ratios (which reflect net MMP activity). Our results suggest that more lipophilic statins (simvastatin and atorvastatin), but not the hydrophilic statin pravastatin, downregulate net MMP-9 activity. However, atorvastatin and pravastatin may downregulate net MMP-2 activity. The clinical implications of the present findings deserve further investigation.
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Using the classical twin design, this study investigates the influence of genetic factors on the large phenotypic variance in inspection time (IT), and whether the well established IT-IQ association can be explained by a common genetic factor. Three hundred ninety pairs of twins (184 monozygotic, MZ; 206 dizygotic, DZ) with a mean age of 16 years participated, and 49 pairs returned approximately 3 months, later for retesting. As in many IT studies, the pi figure stimulus was used and IT was estimated from the cumulative normal ogive. IT ranged from 39.4 to 774.1 ms (159 +/- 110.1 ms) with faster ITs (by an average of 26.9 ms) found in the retest session from which a reliability of .69 was estimated. Full-scale IQ (FIQ) was assessed by the Multidimensional Aptitude Battery (MAB) and ranged from 79 to 145 (111 +/- 13). The phenotypic association between IT and FIQ was confirmed (- .35) and bivariate results showed that a common genetic factor accounted for 36% of the variance in IT and 32% of the variance in FIQ. The maximum likelihood estimate of the genetic correlation was - .63. When performance and verbal IQ (PIQ & VIQ) were analysed with IT, a stronger phenotypic and genetic relationship was found between PIQ and IT than with VIQ. A large part of the IT variance (64%) was accounted for by a unique environmental factor. Further genetic factors were needed to explain the remaining variance in IQ with a small component of unique environmental variance present. The separability of a shared genetic factor influencing IT and IQ from the total genetic variance in IQ suggests that IT affects a specific subcomponent of intelligence rather than a generalised efficiency. (C) 2001 Elsevier Science Inc. All rights reserved.
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Groupers (Epinephelinae) are prominent marine fishes distributed in the warmer waters of the world. Review of the literature suggests that trematodes are known from only 62 of the 159 species and only 9 of 15 genera; nearly 90% of host-parasite combinations have been reported only once or twice. All 20 families and all but 7 of 76 genera of trematodes found in epinephelines also occur in non-epihephelines. Only 12 genera of trematodes are reported from both the Atlantic-Eastern Pacific and the Indo-West Pacific. Few (perhaps no) species are credibly cosmopolitan but some have wide distributions across the Indo-West Pacific. The hierarchical 'relatedness' of epinephelines as suggested by how they share trematode taxa (families, genera, species) shows little congruence with what is known of their phylogeny. The major determinant of relatedness appears to be geographical proximity. Together these attributes suggest that host-parasite coevolution has contributed little to the evolution of trematode communities of epinephelines. Instead, they appear to have arisen through localized episodes of host-switching, presumably both into and out of the epinephelines. The Epinephelinae may well be typical of most groups of marine fishes both in the extent to which their trematode parasites are known and in that, apparently, co-evolution has contributed little to the evolution of their communities of trematodes.
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It has been reported that there is a relationship between a single-nucleotide polymorphism (SNP) in the promoter region of the CD 14 gene at position -159 (C-->T) and infectious diseases. The aim of the present study was to test the hypthesis that expression of this SNP correlates with periodontal disease in a Japanese population. The CD14 genotype was determined in 163 subjects with periodontitis and in 104 age- and gender-matched control subjects without periodontitis. The genotype distribution and allele frequency within the periodontitis patients were not significantly different from those of control subjects. There was, however, a significant difference in the genotype distribution between young patients (< 35 yrs) and older patients (greater than or equal to 35 yrs). These findings suggest that CD14-159C/T polymorphism is not related to the development of periodontitis in a Japanese population, but that, within the periodontitis subjects, expression of the SNP may be related to early disease activity.
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Projetos premiados no 6?? Concurso de Inova????es na Gest??o P??blica Federal - Pr??mio Helio Beltr??o. Representam contribui????es para a melhoria da gest??o p??blica nas seguintes ??reas: planejamento e gest??o estrat??gica, articula????o de parcerias, atendimento ao usu??rio, gerenciamento de informa????es, gest??o financeira e or??ament??ria, gest??o de pessoas e capacita????o, gest??o de servi??os gerais, gest??o de suprimentos e simplifica????o e agiliza????o de procedimentos
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Este projeto refere-se ?? implementa????o de processos de treinamento em microinform??tica realizada pela Dataprev, utilizando uma metodologia autoinstrucional - CBT (Computer Based Trainning). Esta metodologia foi adotada no programa TREINABEM, o que possibilitou uma economia de custos consider??vel, al??m de levar a uma mudan??a cultural a favor do aprendizado aut??nomo e cont??nuo
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Com o crescimento do n??mero de solicita????es para publica????o e o conseq??ente aumento das atividades, percebeu-se que o atendimento aos usu??rios deixava a desejar. Foi adotado, ent??o, o sistema de rod??zio, de modo que todos os funcion??rios ??? sem exce????o ??? ficassem aptos a atender a qualquer situa????o no setor, oferecendo aos usu??rios um atendimento mais r??pido e mais preciso. Os funcion??rios passaram a ter uma vis??o mais abrangente do processo do trabalho e manifestaram maior satisfa????o com o envolvimento total nas atividades do setor. Diversos funcion??rios superaram receios quanto ??s suas supostas limita????es profissionais. Todos descobriram sua capacidade para substituir uns aos outros, aumentou a coopera????o e a responsabilidade de cada um para com o resultado final do trabalho. Os funcion??rios descobriram a import??ncia da sua participa????o e passaram a apresentar sugest??es, ansiando por mais melhorias no desenrolar di??rio dos trabalhos. Os usu??rios manifestaram sua satisfa????o com a melhoria do atendimento
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No ano de seu centen??rio, celebrar o nome de Josu?? de Castro ultrapassa a mera sauda????o ao ge??grafo, intelectual, professor e diplomata pernambucano, autor de Geografia da Fome, seu mais c??lebre livro datado de 1946 e traduzido em mais de 25 idiomas. Seu m??rito est?? inscrito em um amplo e consolidado legado de toda uma vida e obra dedicadas ao combate ?? fome, verdadeiro libelo que denuncia um dos maiores flagelos da humanidade.
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A an??lise da literatura brasileira sobre educa????o a dist??ncia ?? ainda limitada no que diz respeito a estudos que investiguem o fen??meno da evas??o, em especial, em contextos de escolas de governo. Este artigo procura identificar e analisar os fatores que contribuem para a evas??o de participantes nos cursos de educa????o continuada a dist??ncia em uma organiza????o governamental respons??vel pela capacita????o dos servidores da administra????o p??blica federal. A ??nfase das investiga????es encontra-se nas vari??veis referentes ??s dificuldades pessoais, profissionais e tecnol??gicas, ??s peculiaridades do curso e caracter??sticas da clientela, contrastadas com as vari??veis demogr??ficas referentes ?? evas??o em cursos a dist??ncia mediados por tecnologias da informa????o e da comunica????o. O trabalho ?? embasado em metodologia quantitativa, por meio de pesquisa descritiva de campo junto aos participantes, valendo-se do uso de question??rio eletr??nico. Procura contribuir para investiga????es sobre o tema, em especial no que se refere aos servidores p??blicos.
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Artigos científicos defesa fitossanitária.
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Este trabalho apresenta e discute diferentes aspectos da realidade da Pós-Graduação brasileira, relevantes para a discussão de sua produção intelectual. Também são descritas e discutidas as estratégias adotadas para a avaliação dessa produção.