681 resultados para Hyper-théâtralité


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At head of title: Hetaireia tēs Hyper tōn Patriōn Amynēs.

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Since the landmark contributions of Homer Smith and co-workers in the 1930s there has been a considerable advance in our knowledge regarding the osmoregulatory strategy of elasmobranch fish. Smith recognised that urea was retained in the body fluids as part of the 'osmoregulatory ballast' of elasmobranch fish so that body fluid osmolality is raised to a level that is iso- or slightly hyper-osmotic to that of the surrounding medium. From studies at that time he also postulated that many marine dwelling elasmobranchs were not capable of adaptation to dilute environments. However, more recent investigations have demonstrated that, at least in some species, this may not be the case. Gradual acclimation of marine dwelling elasmobranchs to varying environmental salinities under laboratory conditions has demonstrated that these fish do have the capacity to acclimate to changes in salinity through independent regulation of Na+, Cl- and urea levels. This suggests that many of the presumed stenohaline marine elasmobranchs could in fact be described as partially euryhaline. The contributions of Thomas Thorson in the 1970s demonstrated the osmoregulatory strategy of a fully euryhaline elasmobranch, the bull shark, Carcharhinus leucas, and more recent investigations have examined the mechanisms behind this strategy in the euryhaline elasmobranch, Dasyatis sabina. Both partially euryhaline and fully euryhaline species utilise the same physiological processes to control urea, Na+ and Cl- levels within the body fluids. The role of the gills, kidney, liver, rectal gland and drinking process is discussed in relation to the endocrine control of urea, Na+ and Cl- levels as elasmobranchs acclimate to different environmental salinities. (C) 2003 Elsevier Inc. All rights reserved.

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Urotensin-II (UII) is a highly potent endogenous peptide within the cardiovascular system. Through stimulation of Galphaq-coupled UT receptors, UII mediates contraction of vascular smooth muscle and endothelial-dependent vasorelaxation, and positive inotropy in human right atrium and ventricle. A pathogenic role of the UT receptor system is emerging in cardiovascular disease states, with evidence for upregulation of the UT receptor system in patients with congestive heart failure (CHF), pulmonary hypertension, cirrhosis and portal hypertension, and chronic renal failure. In vitro and in vivo studies show that under pathophysiological conditions, UII might contribute to cardiomyocyte hypertrophy, extracellular matrix production, enhanced vasoconstriction, vascular smooth muscle cell hyperplasia, and endothelial cell hyper-permeability. Single nucleotide polymorphisms of the UII gene may also impart a genetic predisposition of patients to diabetes. Therefore, the UT receptor system is a potential therapeutic target in the treatment of cardiac, pulmonary, and renal diseases. UT receptor antagonists are currently being developed to prevent and/or reverse the effects of over-activated UT receptors by the endogenous ligand. This review describes UII peptide and converting enzymes, and UT receptors in the cardiovascular system, focusing on pathophysiological roles of UII in the heart and blood vessels. (C) 2004 Elsevier Inc. All rights reserved,

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Recently we have shown that growth hormone (GH) inhibits neuronal differentiation and that this process is blocked by suppressor of cytokine signalling-2 (SOCS2). Here we examine several cortical and subcortical neuronal populations in GH hyper-responsive SOCS2 null (-/-) mice and GH non-responsive GH receptor null (GHR-/-) mice. While SOCS2-/- mice showed a 30% decrease in density of NeuN positive neurons in cortex compared to wildtype, GHR-/- mice showed a 25% increase even though brain size was decreased. Interneuron sub-populations were variably affected, with a slight decrease in cortical parvalbumin expressing interneurons in SOCS2-/- mice and an increase in cortical calbindin and calretinin and striatal cholinergic neuron density in GHR-/- mice. Analysis of glial cell numbers in cresyl violet or glial fibrillary acidic protein (GFAP) stained sections of cortex showed that the neuron: glia ratio was increased in GHR-/- mice and decreased in SOCS2-/- mice. The astrocytes in GHR-/- mice appeared smaller, while they were larger in SOCS2-/- mice. Neuronal soma size also varied in the different genotypes, with smaller striatal cholinergic neurons in GHR-/- mice. While the size of layer 5 pyramidal neurons was not significantly different from wildtype, SOCS2-/- neurons were larger than GHR-/- neurons. In addition, primary dendritic length was similar in all genotypes but dendritic branching of pyramidal neurons in the cortex appeared sparser in GHR-/- and SOCS2-/- mice. These results suggest that GH, possibly regulated by SOCS2, has multiple effects on central nervous system (CNS) development and maturation, regulating the number and size of multiple neuronal and glial cell types.

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This study examined the osmoregulatory status of the euryhaline elasmobranch Carcharhinus leucas acclimated to freshwater (FW) and seawater ( SW). Juvenile C. leucas captured in FW ( 3 mOsm l(-1) kg(-1)) were acclimated to SW ( 980 - 1,000 mOsm l(-1) kg(-1)) over 16 days. A FW group was maintained in captivity over a similar time period. In FW, bull sharks were hyper-osmotic regulators, having a plasma osmolarity of 595 mOsm l(-1) kg(-1). In SW, bull sharks had significantly higher plasma osmolarities ( 940 mOsm l(-1) kg(-1)) than FW-acclimated animals and were slightly hypoosmotic to the environment. Plasma Na+, Cl-, K+, Mg2+, Ca2+, urea and trimethylamine oxide (TMAO) concentrations were all significantly higher in bull sharks acclimated to SW, with urea and TMAO showing the greatest increase. Gill, rectal gland, kidney and intestinal tissue were taken from animals acclimated to FW and SW and analysed for maximal Na+/ K+-ATPase activity. Na+/ K+-ATPase activity in the gills and intestine was less than 1 mmol Pi mg(-1) protein h(-1) and there was no difference in activity between FW- and SW-acclimated animals. In contrast Na+/ K+-ATPase activity in the rectal gland and kidney were significantly higher than gill and intestine and showed significant differences between the FW- and SW-acclimated groups. In FW and SW, rectal gland Na+/ K+-ATPase activity was 5.6 +/- 0.8 and 9.2 +/- 0.6 mmol Pi mg(-1) protein h(-1), respectively. Na+/ K+-ATPase activity in the kidney of FW and SW acclimated animals was 8.4 +/- 1.1 and 3.3 +/- 1.1 Pi mg(-1) protein h(-1), respectively. Thus juvenile bull sharks have the osmoregulatory plasticity to acclimate to SW; their preference for the upper reaches of rivers where salinity is low is therefore likely to be for predator avoidance and/or increased food abundance rather than because of a physiological constraint.

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The basis for the neuroprotectant effect of D-mannitol in reducing the sensory neurological disturbances seen in ciguatera poisoning, is unclear. Pacific ciguatoxin-1 (P-CTX-1), at a concentration 10 nM, caused a statistically significant swelling of rat sensory dorsal root ganglia (DRG) neurons that was reversed by hyperosmolar 50 MM D-mannitol. However, using electron paramagnetic resonance (EPR) spectroscopy, it was found that P-CTX-1 failed to generate hydroxyl free radicals at concentrations of toxin that caused profound effects on neuronal excitability. Whole-cell patch-clamp recordings from DRG neurons revealed that both hyper- and iso-osmolar 50 MM D-mannitol prevented the membrane depolarisation and repetitive firing of action potentials induced by P-CTX-1. In addition, both hyper- and iso-osmolar 50 MM D-mannitol prevented the hyperpolarising shift in steady-state inactivation and the rise in leakage current through tetrodotoxin (TTX)-sensitive Na-v channels, as well as the increased rate of recovery from inactivation of TTX-resistant Nav channels induced by P-CTX-1. D-Mannitol also reduced, but did not prevent, the inhibition of peak TTX-sensitive and TTX-resistant I-Na amplitude by P-CTX-1. Additional experiments using hyper- and isoosmolar D-sorbitol, hyperosmolar sucrose and the free radical scavenging agents Trolox (R) and L-ascorbic acid showed that these agents, unlike D-mannitol, failed to prevent the effects of P-CTX-1 on spike electrogenesis and Na-v channel gating. These selective actions of D-mannitol indicate that it does not act purely as an osmotic agent to reduce swelling of nerves, but involves a more complex action dependent on the Nav channel subtype, possibly to alter or reduce toxin association. (c) 2005 Elsevier Ltd. All rights reserved.

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Starting from a comparison between the process of writing by hand and writing to screen, this paper contends that there is a continuity between the former, apparently archaic form of writing, and the latter, supposedly more modern form of writing. It will be suggested that, rather than being truly archaic, writing by hand perhaps constitutes a nostalgic act which attempts to bypass the perceived virtuality of the postmodern condition. As such, it will be claimed, via Baudrillard, that nostalgia of this kind is a type of hyper-simulacrum that relies on a misinterpretation of the noise created by the very act of expression. It will be claimed, however, that if interpreted without the sort of wilful misinterpretation to which noise often falls prey, many kinds of noise grafted onto contemporary cultural objects bear testimony to a certain continuity across historical eras as well as to the fact that we are ultimately incapable of recognising many cultural products' noise (and thus the products themselves in their entirety) in their own era. This paper therefore calls for a noisy theory which, analysing the world from an immanent position, would acknowledge the impossibility of full knowledge of the sign

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The aim of this study was to determine the relative cryopreservation success of koala and wombat spermatozoa and to investigate reasons for their respective post-thaw survival by examining the sperm's response to a range of osmotic media and determining the presence and distribution of F-actin. An hypothesis was proposed that F-actin may be imparting a degree of structural inflexibility to the koala sperm plasma membrane; hence, exposure of spermatozoa to cytochalasin D (5 mu M), a F-actin depolymerisation agent, should result in increased plasticisation of the membrane and greater tolerance of cell volume changes that typically occur during cryopreservation. In experiment 1, koala (n = 4) and wombat (n = 4) spermatozoa packaged in 0.25 mL straws were cryopreserved using two freezing rates (fast-3 cm above liquid N2 interface; slow-6 degrees C/min in a freezing chamber) and two glycerol concentrations (8 and 14% v/v) in a tris-citrate glucose buffer with 15% (v/v) egg yolk. Wombat spermatozoa showed better (P < 0.01) post-thaw survival (% motile, % intact plasma membranes, % decondensed sperm heads) than koala spermatozoa. When exposed to media of varying osmolality, koala spermatozoa were less tolerant (% intact plasma membrane) of hyper-osmotic conditions (920 and 1410mOsmol/kg) than wombat spermatozoa. F-actin was localised using a monoclonal antibody but only found in the wombat sperm head. When koala and wombat spermatozoa were exposed to media of varying osmolality, cytochalasin D had no beneficial effect on sperm survival (% intact plasma membranes). This study has demonstrated that wombat spermatozoa are highly tolerant of cryopreservation when compared to koala sperm but that spermatozoa from both species show greatest post-thaw survival when frozen slowly in 14% glycerol. Koala sperm are also particularly susceptible to hyper-osmotic environments but lack of detectable F-actin in the koala spermatozoan suggests that poor cryopreservation success in this species is unlikely to be associated with F-actin induced plasma membrane inflexibility. (c) 2006 Elsevier Inc. All rights reserved.

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Monogenic mutations leading to excessive activation of the mineralocorticoid pathway result, almost always, in suppressed renin and hypertension in adult life and sometimes in hypokalaemia and alkalosis, which can be severe. In most of these syndromes, precise molecular changes in specific steroidogenic or effector genes have been identified, permitting appreciation of (1) pathophysiology, (2) great diversity of phenotype and (3) possibility of genetic methods of diagnosis. Yet to be achieved elucidation of the genetic basis of familial hyperaldosteronism type 11, the most common and clinically significant of them, will enhance detection of primary aldosteronism, currently the commonest specifically treatable and potentially curable form of hypertension. While classic, complete-phenotype presentations of monogenic forms of mineralocorticoid hypertension are rarely recognised, more subtle genetic expression causing less florid manifestations could represent a significant proportion of so-called 'essential hypertension.'

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Objective. Twelve families that were multiply affected with diffuse idiopathic skeletal hyperostosis (DISH) and/or chondrocalcinosis, were identified on the island of Terceira, The Azores, potentially supporting the hypothesis that the 2 disorders share common etiopathogenic factors. The present study was undertaken to investigate this hypothesis. Methods. One hundred three individuals from 12 unrelated families were assessed. Probands were identified from patients attending the Rheumatic Diseases Clinic, Hospital de Santo Espirito, in The Azores. Family members were assessed by rheumatologists and radiologists. Radiographs of all family members were obtained, including radiographs of the dorsolumbar spine, pelvis, knees, elbows, and wrists, and all cases were screened for known features of chondrocalcinosis. Results. Ectopic calcifications were identified in 70 patients. The most frequent symptoms or findings were as follows: axial pain, elbow, knee and metacarpophalangeal (MCP) joint pain, swelling, and/or deformity, and radiographic enthesopathic changes. Elbow and MCP joint periarticular calcifications were observed in 35 and 5 patients, respectively, and chondrocalcinosis was identified in 12 patients. Fifteen patients had sacroiliac disease (ankylosis or sclerosis) on computed tomography scans. Fifty-two patients could be classified as having definite (17%), probable (26%), or possible (31%) DISH. Concomitant DISH and chondrocalcinosis was diagnosed in 12 patients. Pyrophosphate crystals were identified from knee effusions in 13 patients. The pattern of disease transmission was compatible with an autosomal-dominant monogenic disease. The mean age at which symptoms developed was 38 years. Conclusion. These families may represent a familial type of pyrophosphate arthropathy with a phenotype that includes peripheral and axial enthesopathic calcifications. The concurrence of DISH and chondrocalcinosis suggests a shared pathogenic mechanism in the 2 conditions.

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Ethological studies of animals in groups and sociobiology indicate that hierarchies of dominance amongst some species ensure the survival of the group. When transferred to human groups, dominance hierarchies suggest a crucial role played by recasting the scope of such hierarchies of dominant and subordinate members to included hyper-dominant beings. A recognition of such beings as even more dominant than the socially dominant members of a hierarchy facilitates the empowerment of the socially subordinate members. Religious belief and practice works to establish such hyper-dominant beings (gods, goddesses, and so forth) as superior members of human groups. Doing so is a means of ensuring the survival of the species and, thus, enhancing healing and human health. The doctor-patient relationship is examined from such a point of view, with an emphasis on whether the hierarchy created by the relationship allows consideration of alternative and complementary forms of medical treatment.

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O trabalho proposto é a montar um projeto exploratório funcional que parta da cartografia cognitiva, que é definida como a arte, teoria e técnica de construir mapas do conhecimento, visando com esta cartografia a sua aplicabilidade na estruturação de um conjunto de cursos/saberes da área da Comunicação. Assemelhado ao conceito de mapas conceituais, ou cognitivos, representam o conhecimento organizado e são compostos por conceitos. Este mapas foram desenvolvido a partir da década de setenta por vários pesquisadores. A tese experimento foi montada tendo como base os softwares de relacionamento por temas e interesses dentro de um ambiente de interatividade tridimensional , montado no conceito de arvore do conhecimento relacional. Esta experiência é construída em ambiente tridimensional com uso de softwares 3D que rodam como aplicativos de engines de vídeo games, que são motores gráficos. A base de dados e a interatividade de textos e tarefas é realizada sob a plataforma do MediaWiki, que é o software aberto que roda a Wikipédia. A plataforma de mapas roda dentro de um software MindJet MindManager e do CMAPS. As vídeo conferências são administradas pelo FlashMeeting, de Web conferência. A maioria deles são softwares abertos. Todos operando em sistemas presenciais ou de modulação EAD. A base conceitual está estruturada dentro de uma visão de educação disruptiva, que lança um novo modelo educacional baseado em mapas, visto dentro de uma abordagem de um mundo de múltiplas telas, um mundo da era hiper, um mundo hipermoderno, que tem como base uma cultura da era tecnológica, numa renovação dos conceitos de Cultura, agora revigorados à luz das novas tecnologias e da nova sociedade interligada em rede.

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O trabalho aborda o empobrecimento estético-discursivo da canção popular massiva exposta na mídia televisiva brasileira, na comparação entre o contexto histórico-midiático-musical das décadas de 1960 e 1970 e o contexto da primeira metade da segunda década do século XXI. Para definir tal empobrecimento discursivo encontrou-se o conceito de desmusicalização da mídia televisiva . O trabalho, de natureza teórica, tem como objetivo apontar que a mídia televisiva tem papel preponderante e parte importante da responsabilidade pelo empobrecimento na construção do discurso da música popular brasileira. Para tanto, primeiramente, por meio da análise poético-estética dos elementos estruturais das linguagens musical e literária de uma canção popular, delimitou-se a espécie de obra musical estruturada com acuro poético, que a ela empresta um padrão estético de excelência. Tais canções tinham espaços de veiculação nas grades de programação da mídia televisiva de outrora e nos dias atuais não mais os têm. Em seguida, por meio de pesquisas bibliográfica, documental e empírica, descreve-se de modo analítico-interpretativo o período histórico em que ocorreu essa desmusicalização da mídia. Por fim, constata-se que a partir da popularização da Internet e da proliferação de diversas mídias que permitem ao ouvinte o acesso, o armazenamento, o compartilhamento de repertórios musicais e, sobretudo, a audição em movimento, a canção popular massiva pautada pelo acuro poético deixou de estar presente na mídia televisiva e passou a figurar em outras diversas mídias. Essa ampla presença da Música nas mídias digitais definiu-se pelo conceito de hipermidiatização da música, que seria um dos componentes da desmusicalização da mídia televisiva.