996 resultados para Bernardo de Cabrera


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A wealth of evidence suggests a role for brain-derived neurotrophic factor (BDNF) and its receptor tropomyosin-related kinase B (TrkB) in the aetiology of depression and in the mode of action of antidepressant drugs. Less clear is the involvement of this neurotrophin in other stress-related pathologies such as anxiety disorders. The dorsal periaqueductal grey matter (DPAG), a midbrain area rich in BDNF and TrkB receptor mRNAs and proteins, has been considered a key structure in the pathophysiology of panic disorder. In this study we investigated the effect of intra-DPAG injection of BDNF in a proposed animal model of panic: the escape response evoked by the electrical stimulation of the same midbrain area. To this end, the intensity of electrical current that needed to be applied to DPAG to evoke escape behaviour was measured before and after microinjection of BDNF. We also assessed whether 5-HT- or GABA-related mechanisms may account for the putative behavioural/autonomic effects of the neurotrophin. BDNF (0.05, 0.1, 0.2 ng) dose-dependently inhibited escape performance, suggesting a panicolytic-like effect. Local microinjection of K252a, an antagonist of TrkB receptors, or bicuculline, a GABA(A) receptor antagonist, blocked this effect. Intra-DPAG administration of WAY-100635 or ketanserin, respectively 5-HT(1A) and 5-HT(2A/2c) receptor antagonists, did not alter BDNF`s effects on escape. Bicuculline also blocked the inhibitory effect of BDNF on mean arterial pressure increase caused by electrical stimulation of DPAG. Therefore, in the DPAG, BDNF-TrkB signalling interacts with the GABAergic system to cause a panicolytic-like effect.

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The development of HTLV-1 associated clinical manifestations, such as TSP/HAM and ATLL, occur in 2-4% of the infected population and it is still unclear why this infection remains asymptomatic in most infected carriers. Recently, it has been demonstrated that HTLV uses the Glucose transporter type 1 (GLUT1) to infect T-CD4(+) lymphocytes and that single nucleotide polymorphisms (SNP) in the GLUT1 gene are associated with diabetic nephropathy in patients with diabetes mellitus in different populations. These polymorphisms could contribute to a higher GLUT1 protein expression on cellular membrane, facilitating the entry of HTLV and its transmission cell by cell. This could result in a higher provirus load and consequently in the development of TSP/HAM. To evaluate the role of GLUT1 gene polymorphisms in the development of TSP/HAM in HTLV-1 infected individuals, the g.22999G > T, g.15339T > C and c.-2841A > T sites were analyzed by PCR/RFLP or sequencing in 244 infected individuals and 102 normal controls. The proviral load of the HTLV-1 infected patients was also analyzed using Real Time Quantitative PCR. Genotypic and allelic frequencies of the three sites did not differ significantly between controls and HTLV-1 infected individuals. There was no difference in genotypic and allelic distributions among patients as to the presence or absence of HTLV-1 associated clinic manifestations. As regards the quantification of the provirus load, we observed a significant reduction in the asymptomatic individuals compared with the oligosymptomatic and TSP/HAM individuals. These results suggest that g.22999G > T, g.15339T > C, and c.-2841A > T SNP do not contribute to HTLV-1 infection nor to the genetic susceptibility of TSP/HAM in Brazilian HTLV-1 infected individuals. J. Med. Virol. 81:552557, 2009. (C) 2009 Wiley-Liss, Inc.

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The present study evaluated the reproductive compatibility of the crosses between adult ticks of the following three geographically different populations of Amblyomma cajennense: State of So Paulo (SP), southeastern Brazil; State of Rondnia (RO), northern Brazil; and Colombia (CO). In addition, crosses between A. cajennense ticks from Argentina (AR) and SP ticks were also performed. The Argentinean population (AR) was compatible with SP because their crosses resulted in high % egg hatching (mean values ranging from 71.5 to 93.5%), similarly to all homologous (intrapopulational) crosses. In contrast, the tick populations SP, RO, and CO were shown to be incompatible with each other, since their heterologous (interpopulational) crosses always resulted in very low % egg hatching (range: 0-5%). The F(1) larval offspring derived from some of these females that yielded 5% egg hatching were reared until the F(1) adult stage. In all cases, only adult females molted from engorged nymphs. These F(1) females were likely to be a product of thelytokous parthenogenesis of the SP, RO, and CO females that were used in the heterologous crosses. Reproductive incompatibility is not expected to occur between different populations of a single species. Thus, our results suggest that the taxon A. cajennense might be represented by a complex of different species, whereas SP and AR ticks might represent a single species. Further populational genetic studies, coupled with extensive morphological analyses, are needed to clarify and determine a possible complex of valid species that might have been classified under the taxon A. cajennense.

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Considering the importance of neosporosis in the animal health and production, the frequency of antibodies to Neospora caninum was evaluated in dairy cattle of the Southwestern region of Mato Grosso State, Brazil, in addition to serum samples obtained from dogs and humans living in the farms. A total of 1036 serum samples were analyzed, from which 932 were from dairy bovine females, 37 from dogs and 67 from humans, from 24 farms and examined by the indirect fluorescent antibody test (IFAT). Reactive human scrum samples were retested by Western-blotting to confirm the results. Antibodies to N. caninum were found in 499 cattle sera (53.5 %), with at least one positive in each farm, 25 dog sera (67.6 %) and seven human sera (10.5 %). There was no significant difference in the number of positive cattle sera according to age group. The results indicate a wide dissemination of N caninum in the studied region.

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Larval behavioral diapause was shown to be the major factor controlling the 1-yr generation pattern of Amblyomma cajennense (F.) (Acari: Ixodidae) in Brazil. During fieldwork, this behavior was shown to coincide with long daylength (>12 h) and high mean ground temperature (approximate to 25 degrees C), which prevail during spring-summer in Brazil. The current study evaluated biological parameters of engorged females, their eggs, and the resultant larvae inside plastic pots planted with the grass Brachiaria decumbens Stapf. held in incubators set with different combinations of temperature and photoperiod. Both the long daylength (photoperiod 14:10 [L:D]h) and high temperature (25 degrees C) during larval hatching induced larval behavioral diapause, characterized by the confinement of hatched larvae on the ground below the vegetation for many weeks. When long daylength was present during hatching, but temperature was low (15 degrees C), larvae did not enter diapause. Similarly, when short daylength (10:14 or 12:12) was present during larval hatching, larvae did not enter diapause regardless whether temperature was high (25 degrees C). Termination of diapause was induced by shifting photoperiod from 14:10 to 12:12 or the temperature from 25 to 15 degrees C. When applied to field conditions, the present results indicate that both high ground mean temperature (approximate to 25 degrees C) and long daylength (>12 h) during spring-summer (October-March) are responsible for the induction and maintenance of A. cajennense larval behavioral diapause in the field. Furthermore, both the low ground mean temperature (-20 degrees C) and the short daylength (<12h) during autumn (April-May) are responsible for termination of larval behavioral diapause in the field.

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The life cycle of Ixodes luciae was evaluated for five consecutive generations in the laboratory. Wild mice Calomys callosus and laboratory rats Rattus norvegicus were used as hosts for larvae and nymphs. For adult ticks, opossums Didelphis aurita were used as hosts. Off-host developmental periods were observed in an incubator at 27A degrees C and 95% RH. The life cycle of I. luciae lasted 95-97 days, excluding prefeeding periods. C. callosus, one of the natural host species for I. luciae immature stages, was shown to be much more suitable than the artificial host R. norvegicus. Significantly (P < 0.05), more larvae and nymphs successfully fed on C. callosus than on R. norvegicus. When tick-na < ve C. callosus were exposed to three consecutive larval infestations at 24-day intervals, recovery of engorged larvae were greater in the second and third infestations, indicating that previous infestations did not induce acquired resistance to ticks. Larval feeding period typically varied from 5 to 10 days on R. norvegicus, but was significantly (P < 0.05), longer on C. callosus (range, 7-34 days). The majority (71.7%) of I. luciae adult females successfully fed and oviposited after exposed to D. aurita. Mean engorged weight (581.9 mg; range, 237.1-796.0 mg) of these females were much higher than those previously reported for other New World Ixodes species. Our results are in accordance to the current literature that appoints opossums Didelphidae and small rodents (e.g., C. callosus) natural hosts for I. luciae immature and adult stages, respectively.

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Because of their multifactorial etiologies, dental and skeletal open bites are among the most difficult malocclusions to treat to a successful and stable result. Etiologic factors include vertical maxillary excess, skeletal pattern, abnormalities in dental eruption, and tongue-thrust problems. The purpose of this article was to report the treatment of an adult patient with a lateral open bite and a unilateral posterior crossbite. The treatment involved nonextraction therapy, including intermaxillary elastics, to obtain dentoalveolar extrusion in the region of the lateral open bite. The treatment results were successful and remained stable 2 years later. (Am J Orthod Dentofacial Orthop 2010;137:701-11)

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A grazing trial to study the effect of stocking rate on animal production and botanical composition of Gallon panic (Panicum maximum) and Estrella grass (Cynodon nlemfuensis) was conducted in the central region of the Paraguayan Chaco between 1992 and 1998. The experiment included 6 stocking rates (0.5, 0.8. 1.1, 1.4. 1.7 and 2.0 AU/ha) on individual 4-ha paddocks. The pasture treatments were continuously grazed by yearling steers. replaced annually, over a 4-year grazing period. No fertiliser was used. Botanical composition was recorded annually in autumn from 1992 to 1998 while animal production data were recorded monthly from 1992 to 1996. Relationships between animal productivity and stocking rates were determined by regression analysis. Gallon panic produced greater liveweight gains per head than Estrella grass at low and intermediate stocking rates. However, the slope of the linear relationship between liveweight gain per head and stocking rate increased each year in Gallon panic indicating that the productivity of this grass progressively declined at higher stocking rates over the period of observation. Estrella grass showed less sensitivity to stocking rate but was affected severely by periods of low rainfall.

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Nodal shoot cultures of 'Clone 003', a selected Australian papaya cultivar, were cultured on modified De Fossard medium supplemented with chemicals that either promote ethylene evolution or inhibit action while in culture. Nodal shoot cultures grown in the presence of 1-aminocyclopropane carboxylic acid (ACC, 1.0 mM) resulted in a significant reduction in percent fresh and dry weights, shoot length, leaf area, petiole length and chlorophyll content, but leaf development was significantly increased. In contrast, nodal cultures grown in the presence of silver thiosulphate (STS, 0.5 mM) significantly produced the highest percentage of fresh and dry weights, shoot length, leaf production, leaf area expansion, petiole length and leaf chlorophyll content. Nodal cultures and rooted whole plantlets placed in medium-sized (125 mL) culture vessels had significantly better growth than those cultures placed in small (70 mL) or in large (250 mL) vessels. Cultures grown in medium-sized vessels had higher fresh and dry weights, longer shoots, more leaves and larger leaf area than those cultures placed in smaller or larger vessels. Similarly, values for said growth parameters and for chlorophyll content of the nodal and rooted whole plantlets were higher when they were incubated under high light intensity of 120 mumol m(-2)s(-1) at a prevailing temperature of either 20+/-1 C or 25+/-1 C.

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O livro materializa a quintess??ncia dos debates travados pelo seleto grupo de representantes educadores ??? de diversas institui????es brasileiras ??? no ciclo de reuni??es promovidas sob a coordena????o da ENAP e que foram realizadas em Bras??lia, em 2006. ?? uma obra que busca ampliar as discuss??es sobre conceitos de educa????o que se desenrolam ao longo da vida, especialmente na contemporaneidade, no contexto da sociedade global que tem exigido compet??ncias e capacidades cada vez mais complexas para a forma????o profissional, notadamente para o setor de servi??os p??blicos

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Introdução: A concentração da creatinina no plasma é usada para avaliar a função renal, mas a depuração da creatinina plasmática (DCP) constitui método mais sensível para essa finalidade. Objetivo: Correlacionar a DCP em coleta urinária de 12 horas noturna com a de 24 horas. Métodos: Noventa e cinco voluntários (34-64 anos) coletaram urina durante 24 horas em dois frascos: diurno (das 7h às 19h) e noturno (das 19h às 7h do dia seguinte). A coleta de sangue se deu em jejum para medidas bioquímicas. A correlação entre as variáveis foi feita pelo teste Pearson (r) e a concordância de medidas, pelo teste de Bland-Altman. Resultados: Urinas de quatro indivíduos foram recusadas por erro de coleta. Na amostra final (n = 91; 42 homens), havia 23 hipertensos e cinco diabéticos. A DCP (mL/min/1,73 m2) foi menor no período noturno em mulheres (77,8 ± 22,7 versus 88,4 ± 23,6; p < 0,05) e similar em homens (91,2 ± 22,9 versus 97,3 ± 30,9; p > 0,05). As correlações entre a DCP na urina de 12 horas noturna ou diurna e a de 24 horas foram fortes (r = 0,85 e 0,83, respectivamente). Em 85 e 83 dos 91 indivíduos, a medida da DCP noturna e diurna, respectivamente, foi concordante com a de 24 horas. Conclusão: A urina de 12 horas, sobretudo quando coletada à noite, fornece valores de DCP similares àqueles obtidos em coleta de 24 horas. Como essa coleta é mais fácil de ser feita em pacientes ambulatoriais à noite, esse período deveria ser preferido para a medida da filtração glomerular.

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Em geral, a tradição do pensamento metafísico entende que no desenvolvimento histórico da razão há um progresso. A existência do progresso requer o sacrifício do indivíduo ao longo da história. A filosofia de Theodor W. Adorno realiza um exame crítico do processo de esclarecimento vivido no Ocidente. Os estudos de Adorno mostram que a associação entre o “progresso” e o sacrifício da individualidade resulta na barbárie. Deste modo, Adorno evidencia os momentos do irracional conservados na sociedade racionalizada e que ameaçam o processo civilizatório. Neste trabalho, investigamos a influência de Sigmund Freud no pensamento de Adorno. Defendemos que a leitura adorniana de Freud é essencial para a explicação dos fatores subjetivos da personalidade autoritária. No entanto, a razão subjetiva não explica inteiramente os determinantes do caráter autoritário. Por isso, no primeiro capítulo nós apresentamos os pressupostos marxianos da razão objetiva. Além disso, indicamos a relação entre razão objetiva e razão subjetiva. No segundo capítulo, buscamos compreender a teoria de Freud e assinalamos como suas categorias manifestam as condições objetivas assinaladas por Adorno. No terceiro capítulo, examinamos a interpretação marxista realizada por Adorno sobre os determinantes psicológicos que favorecem a manifestação do caráter autoritário. Ao final, nós debatemos os resultados da recepção adorniana de Freud.

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Esta dissertação parte das bases da crítica de Gadamer à consciência estética desde o contexto de fundamentação das ciências naturais e decorrente estabelecimento das ciências humanas. Considerando o posicionamento contrário de Gadamer quanto ao predomínio dos métodos das ciências naturais em todos os âmbitos da experiência humana no mundo, nosso esforço será no sentido de abordar a compreensão da experiência estética. Neste sentido, nos voltaremos para a aisthesis com vistas a caminhar focando na problemática em torno da arte a partir de Platão e Aristóteles, culminando no estabelecimento da estética como campo específico do saber filosófico no pensamento iluminista de Baumgarten. Destarte, o presente escrito voltar-se-á para as bases da consciência estética que se encontram na subjetivação decorrente dos efeitos do pensamento crítico de Kant. Com isso, abordaremos as perspectivas de Gadamer com vistas a liberar a experiência da arte do âmbito da consciência estética, o que, segundo este filósofo, pode ocorrer a partir da assunção de um tipo de experiência que pode ser tomado como verdade mesmo não estando restrito aos métodos das ciências naturais. Partindo desta prerrogativa,Gadamer lança mão da noção de jogo como experiência fora da centralidade subjetiva. Com o redirecionamento da experiência, o fenômeno artístico pode aparecer como parte constitutiva da experiência existencial humana sem estar restrito às faculdades subjetivas.

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Os linfomas do trato nasossinusal são neoplasias incomuns, que reconhecidamente causam importantes lesões destrutivas no nariz e terço médio da face. Sua raridade pode levar os profissionais da área médica a erros no diagnóstico clínico, além de representar um verdadeiro desafio aos patologistas, por sua natureza inflamatória. OBJETIVO: O objetivo deste estudo é determinar os aspectos clínicos e histopatológicos do linfoma não-Hodgkin (LNH) do trato nasossinusal, correlacionando sítio tumoral e comportamento biológico com os subtipos do LNH. FORMA DE ESTUDO: Estudo de série. MATERIAL E MÉTODO: Foi realizada uma análise retrospectiva que incluiu 7 pacientes atendidos no ambulatório do serviço de otorrinolaringologia do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, no período de 1985 a 2003. RESULTADOS: As linhagens de células B e T/NK têm comportamento biológico diferente, assim como o sítio e apresentação clínica, sendo o diagnóstico histopatológico de extrema importância. CONCLUSÃO: A biópsia realizada adequadamente favorecerá um diagnóstico mais precoce e preciso, instituindo rapidamente a terapêutica adequada e melhorando o prognóstico e a sobrevida destes pacientes.

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O Streptococcus pyogenes do grupo A (SGA) é o agente etiológico mais comum das faringoamigdalites (FA). O diagnóstico etiológico correto e tratamento adequado evitam complicações supurativas e não-supurativas da faringoamigdalite estreptocócica, entretanto, métodos clínicos de diagnóstico não são confiáveis. Os métodos rápidos de detecção do antígeno do SGA podem ser utilizados no diagnóstico deste agente e evitar uso indevido de antibióticos. OBJETIVOS: Os autores objetivaram avaliar a sensibilidade e especificidade dos testes rápidos para detecção do antígeno do SGA em nosso meio. FORMA DE ESTUDO: Clínico prospectivo. CASUÍSTICA E MÉTODO: Oitenta e um pacientes com faringoamigdalite aguda, atendidos no PS-ORL do Hospital das Clínicas da FMUSP, no período de maio de 2001 a abril de 2002, foram submetidos a duas coletas simultâneas de material de orofaringe com swabs. O teste rápido de detecção do SGA foi confrontado com a cultura em placa agar-sangue ("gold standard" para o diagnóstico etiológico). RESULTADOS: De 81 pacientes, 56% tiveram teste rápido positivo e 44% negativo; 40.7% apresentaram crescimento de SGA na cultura; a sensibilidade e especificidade do teste rápido foram, respectivamente, 93,9% e 68,7%. O valor preditivo negativo e positivo foram, respectivamente, 94,2% e 67,4%. COMENTÁRIOS FINAIS: A alta sensibilidade do exame permite utilizá-lo com intuito de identificar pacientes com SGA. Os testes de detecção rápida do antígeno estreptocócico se mostraram uma importante arma coadjuvante no diagnóstico etiológico das faringoamigdalites.