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The objectives were to determine if the skin secretion of the European yellow-bellied toad (Bombina variegata), in common with other related species, contains a bradykinin inhibitor peptide and to isolate and structurally characterize this peptide. Materials and Methods: Lyophilized skin secretion obtained from this toad was subjected to reverse phase HPLC fractionation with subsequent bioassay of fractions for antagonism of the bradykinin activity using an isolated rat tail artery smooth muscle preparation. Subsequently, the primary structure of the peptide was established by a combination of microsequencing, mass spectroscopy, and molecular cloning, following which a synthetic replicate was chemically synthesised for bioassay. Results: A single peptide of molecular mass 2300.92 Da was resolved in HPLC fractions of skin secretion and its primary structure determined as IYNAIWP-KH-NK-KPGLL-. Database interrogation with this sequence indicated that this peptide was encoded by skin kininogen-1 previously cloned from B. variegata. The blank cycles were occupied by cysteinyl (C) residues and the peptide was located toward the C-terminus of the skin kininogen, and flanked N-terminally by a classical -KR- propeptide convertase processing site. The peptide was named IC-20 in accordance (I = N-terminal isoleucine, C = C-terminal cysteine, 20 = number of residues). Like the natural peptide, its synthetic replicate displayed an antagonism of bradykinin-induced arterial smooth muscle relaxation. Conclusion: IC-20 represents a novel bradykinin antagonizing peptide from amphibian skin secretions and is the third such peptide found to be co-encoded with bradykinins within skin kininogens.

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Background: after stroke, visual impairment may exacerbate the impact of other impairments on overall disability and negatively influence rehabilitation.

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In the present paper, we introduce a notion of a style representing abstract, complex objects having characteristics that can be represented as structured objects. Furthermore, we provide some mathematical properties of such styles. As a main result, we present a novel approach to perform a meaningful comparative analysis of such styles by defining and using graph-theoretic measures. We compare two styles by comparing the underlying feature sets representing sets of graph structurally. To determine the structural similarity between the underlying graphs, we use graph similarity measures that are computationally efficient. More precisely, in order to compare styles, we map each feature set to a so-called median graph and compare the resulting median graphs. As an application, we perform an experimental study to compare special styles representing sets of undirected graphs and present numerical results thereof. (C) 2007 Elsevier Inc. All rights reserved.

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This article demonstrates the mouvement of poetic speech in Celan's poetics at the exemple of one poem, thus stressing the significance of the poetic form.

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An iron prophyrin complex has been immobilized on the surfaces of platinum, silver, and indium doped-tin oxide coated glass by using the poly(gamma-ethyl L-glutamate)-N-(3-aminopropyl)imidazole derivative 1 as a linking agent, thus allowing-the surface-enhanced resonance Raman and UV-VIS absorption spectra and electrochemical properties of the porphyrin to be studied in solvents in which it is not normally soluble.

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We have investigated the effects of depletion of the elements C, N and O on the chemical composition of dark clouds, using both isothermal and isochoric cloud models. Our work differs from previous approaches in that we have considered a much larger range of CNO depletions. We have included the chemistry of the ortho-and para-forms of H2 and the exothermic reaction between N+ and ortho-H2, which synthesizes NH3. In the isothermal models, the ortho:para ratio is very small at large depletions, but NH3 formation is still efficient owing to reactions between He+ and CN or HCN. In the isochoric models, the equilibrium temperature of the gas is larger, and a thermal ortho:para ratio, which is large enough to drive NH3 formation, results. In all cases, the fractional abundance of NH3 is close to 10(-8) and this may help to explain the puzzling observation that, in dark clouds, the column density of NH3 is always close to 10(15) cm-2.

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Participatory citizenship education has been highlighted as a strategy to promote social cohesion in divided societies whereby collaborations with Non-Governmental Organisations and inter-school links have been proposed as tools to improve social networks between schools and communities. This article explores the role and meaning of citizenship education and cross-community participation in promoting social capital and social cohesion. School survey findings, focus groups and interviews with young people and educators indicated that differences between school sectors and established allegiances with particular communities and NGOs may limit the potential for citizenship education to produce bridging social capital and serve to reproduce bonding social capital. It is argued that the introduction of citizenship curricula into segregated schools systems in divided societies may be useful to promote citizenship values and positive attitudes to the other but insufficient to promote the development of bridging social capital and, ultimately, social cohesion in the long term.