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Selected AbstractsRole of protease-activated receptor-2 during cutaneous inflam-mation and the immune responseEXPERIMENTAL DERMATOLOGY, Issue 9 2004M. Steinhoff Protease-activated receptors (PARs) constitute a new subfamily of G-protein-coupled receptors with seven transmembrane domains which are activated by various serine proteases such as thrombin, cathepsin G, trypsin or tryptase, and bacterial proteases or mite antigens, for example. PAR2 is a receptor for mast cell tryptase or house dust mite allergens, which is released during inflammation and allergic reactions. In the skin, PAR2 is diversely expressed by keratinocytes, endothelial cells, and occasionally sensory nerves of human skin in various disease states. Moreover, immunocompetent cells such as T cells and neutrophils express functional PAR2, thereby contributing to inflammation and host defense. Own data revealed that PAR2 contributes to neurogenic inflammation by releasing neuropeptides from sensory nerves resulting in oedema, plasma extravasation and infiltration of neutrophils. Thus, mast cells may communicate with sensory nerves in inflammatory tissues by activating PAR2 via tryptase. Moreover, PAR2 agonists upregulate the expression of certain cell-adhesion molecules and cytokines such as interleukin-6 and interleukin-8 on dermal microvascular endothelial cells or regulate neutrophil migration, indicating that PAR2 plays an important role in leucocyte/endothelial interactions. These effects may be partly mediated by NF-,B, an important transcription factor during inflammation and immune response. PAR2 stimulation results in the activation of NF-,B on microvascular endothelial cells and keratinocytes, thereby regulating ICAM-1 expression. We also demonstrate evidence for a diverse expression of PAR2 in various skin diseases and highlight the recent knowledge about the important role of PAR2 during inflammation and the immune response. Together, PAR2 -modulating agents may be new tools for the treatment of inflammatory and allergic diseases in the skin. [source] Body size determines the strength of the latitudinal diversity gradientECOGRAPHY, Issue 3 2001Helmut Hillebrand In most groups of organisms, the species richness decreases from the tropics to the poles. The mechanisms causing this latitudinal diversity gradient are still controversial. We present data from a comprehensive weighted meta-analysis on the strength of the latitudinal gradient in relation to body size. We sampled literature data on the correlation between species richness and latitude for a variety of organisms, ranging from trees to protozoa. In addition, own data on the presence of large-scale diversity patterns for diatoms were included, both for local and regional species richness. The strength of the latitudinal gradient was positively correlated to the size of the organisms. Strongest decreases of species richness to the poles was found for large organisms like trees and vertebrates, whereas meiofauna, protozoa and diatoms showed weak or no correlations between species richness and latitude. These results imply that latitudinal gradients are shaped by non-equilibrium (regional) processes and are persistent under conditions of dispersal limitation. [source] The Experimental and Theoretical Study of Phase Equilibria in the Pd,Zn (-Sn) System,ADVANCED ENGINEERING MATERIALS, Issue 3 2006J. Vizdal The binary Pd-Zn system was assessed in the scope of this paper. The experimental data from the literature were used for the assessment, together with our own data obtained by SEM-EDS analysis and by the DTA. The paper is focused particularly on the Pd-Zn system, but the Pd-Sn and Sn-Zn systems are also analysed in this paper. Finally, first prediction of the isothermal sections of the ternary Pd-Sn-Zn system was made. [source] Regulated transcription of the immediate-early gene Zif268: Mechanisms and gene dosage-dependent function in synaptic plasticity and memory formationHIPPOCAMPUS, Issue 5 2002Bruno Bozon Abstract The immediate-early gene Zif268 is a member of the Egr family of inducible transcription factors. Data from gene expression studies have suggested that this gene may play a critical role in initial triggering of the genetic machinery that has long been considered a necessary mechanism for maintenance of the later phases of LTP and also for the consolidation or stabilization of long-lasting memories. Until recently, however, the data supporting this assumption have been based primarily on circumstantial evidence, with no direct evidence to suggest that Zif268 is required for long-lasting synaptic plasticity and memory. In this report, we review our own data using Zif268 mutant mice; we show that although the early phase of dentate gyrus LTP is normal in these mice, the later phases are not present, and the ability of the mice to maintain learned information over a 24-h period is deficient. In addition, we present new information showing a task-dependent gene dosage effect in Zif268 heterozygous mice. We show that spatial learning is particularly sensitive to reduced levels of Zif268, as one-half of the complement of Zif268 in heterozygous mice is insufficient to maintain spatial long-term memories. Hippocampus 2002;12:570,577. © 2002 Wiley-Liss, Inc. [source] WHO/EORTC classification of cutaneous lymphomas 2005: histological and molecular aspectsJOURNAL OF CUTANEOUS PATHOLOGY, Issue 10 2005Günter Burg It reflects the unique features of lymphoproliferative diseases of the skin, and at the same time it is as compatible as possible with the concepts underlying the WHO classification for nodal lymphomas and the EORTC classification of cutaneous lymphomas. This article reviews the histological, phenotypical, and molecular genetic features of the various nosological entities included in this new classification. These findings always have to be interpreted in the context of the clinical features and biologic behavior. Aim:, To review the histological, phenotypical and molecular genetic features of the various nosological entities of the new WHO/EORTC classification for cutaneous lymphomas. Methods:, Extensive review of the literature cited in Medline and own data of the authors. Results:, The WHO/EORTC classification of cutaneous lymphomas comprises mature T-cell and NK-cell neoplasms, mature B-cell neoplasms and immature hematopoietic malignancies. It reflects the unique features of primary cutaneous lymphoproliferative diseases. Conclusion:, This classification is as much as possible compatible with the concept of the WHO classification for nodal lymphomas and the EORTC classification of cutaneous lymphomas. The histological, phenotypical and molecular genetic features always have to be interpreted in the context of the clinical features and biologic behavior. [source] A review of morphological techniques for detection of peroxisomal (and mitochondrial) proteins and their corresponding mRNAs during ontogenesis in mice: Application to the PEX5-knockout mouse with Zellweger syndromeMICROSCOPY RESEARCH AND TECHNIQUE, Issue 2 2003Eveline Baumgart Abstract In the era of application of molecular biological gene-targeting technology for the generation of knockout mouse models to study human genetic diseases, the availability of highly sensitive and reliable methods for the morphological characterization of the specific phenotypes of these mice is of great importance. In the first part of this report, the role of morphological techniques for studying the biology and pathology of peroxisomes is reviewed, and the techniques established in our laboratories for the localization of peroxisomal proteins and corresponding mRNAs in fetal and newborn mice are presented and discussed in the context of the international literature. In the second part, the literature on the ontogenetic development of the peroxisomal compartment in mice, with special emphasis on liver and intestine is reviewed and compared with our own data reported recently. In addition, some recent data on the pathological alterations in the liver of the PEX5,/, mouse with a peroxisomal biogenesis defect are briefly discussed. Finally, the methods developed during these studies for the localization of mitochondrial proteins (respiratory chain complexes and MnSOD) are presented and their advantages and pitfalls discussed. With the help of these techniques, it is now possible to identify and distinguish unequivocally peroxisomes from mitochondria, two classes of cell organelles giving by light microscopy a punctate staining pattern in microscopical immunohistochemical preparations of paraffin-embedded mouse tissues. Microsc. Res. Tech. 61:121,138, 2003. © 2003 Wiley-Liss, Inc. [source] Bat Species Richness in Atlantic Forest: What Is the Minimum Sampling Effort?BIOTROPICA, Issue 2 2003Helena Godoy Bergallo ABSTRACT Species lists are sources of information for studies of both conservation and macroecology. It is, however, important to differentiate between relatively complete lists and extremely incomplete ones. The aim of this study was to evaluate how sampling effort typically used in inventories affects the number of bat species captured in areas of Atlantic Forest in southeastern Brazil. We also evaluated if the number of sampled sites, size of the sampled area, and sampling effort (net hours) affect species richness. We used previously reported data from studies in Rio de Janeiro, São Paulo, and Minas Gerais States, and our own data collected during 1989 and 2001. Nonlinear models fit well the data for Rio de Janeiro and Minas Gerais States and all states together, but not for São Paulo State. Genera richness showed a similar pattern to that of species richness. The model used to explain the relationship between species richness and size of the study area, number of sites, and sampling effort sampled was significant. The number of sites sampled explained a significant part of the variation observed; however, other variables contributed nothing to the model, suggesting that capturing beta diversity is the most important aspect of biodiversity surveys for bats, and that increasing net hours at a given location is much more inefficient than distributing net hours across locations. We suggest 1000 captures as the minimum necessary when sampling with mist nets to capture the majority of phyllostomid species for a given site (alpha diversity). In addition, we suggest that shifting the position of the mist nets between nights will increase the probability of capturing more species. RESUMO As listas de espécies são fontes de informações para estudos, tanto de conservação quanto de macroecologia. Entretanto, é importante diferenciar entre listas relativamente completas daquelas seriamente incompletas. O objetivo deste estudo foi avaliar como o esforco amostral mínimo tipicamente usado em inventários afeta o número de especies de morcegos capturados em áreas de Mata Atlãntica do sudeste do Brasil. Nós também avaliamos se o número de pontos amostrados, o tamanho da área amostrada e o esforço de captura (hora-rede) afetam a riqueza de espécies. Nós usamos dados disponíveis de estudos desenvolvidos nos estados do Rio de Janeiro, São Paulo e Minas Gerais, e os nossos próprios dados coletados de 1989 a 2001. Modelos não-lineares se ajustaram para os estados do Rio de Janeiro e Minas Gerais e todos os estados juntos, mas não para o Estado de São Paulo. A riqueza de g,neros mostrou o mesmo padrão da riqueza de espécies. O modelo usado para expliçãr a relacao entre riqueza de espécies e tamanho da área de estudo, número de pontos amostrados e esforço amostral foi significative. O número de pontos amostrados explicou uma parte significante da variação observada. Contudo, as outras variáveis não contribuiram para o modelo, sugerindo que capturar a diversidade Beta é o aspecto mais importante de inventários de biodiversidade para morcegos, e que o aumento de horas-rede numa dada localidade é muito mais ineficiente do que distribuir horas-rede entre localidades. Nós sugerimos 1000 capturas como o mínimo necessário para amostrar, com redes de neblina, a maioria das espécies de filostomídeos de uma dada área (diversidade Alfa). Adicionalmente, sugerimos que mudando a posição das redes entre noites aumentará a probabilidade de capturar um maior número de espéciesS. [source] Determination of absolute configurations by X-ray crystallography and 1H NMR anisotropyCHIRALITY, Issue 5 2008Nobuyuki Harada Abstract To determine the absolute configurations of chiral compounds, many spectroscopic and diffraction methods have been developed. Among them, X-ray crystallographic Bijvoet method, CD exciton chirality method, and the combination of vibrational circular dichroism and quantum mechanical calculations are of nonempirical nature. On the other hand, X-ray crystallography using a chiral internal reference, and 1H NMR spectroscopy using chiral anisotropy reagents are relative and/or empirical methods. In addition to absolute configurational determinations, preparations of enantiopure compounds are strongly desired. As chiral reagents useful for both the preparation of enantiopure compounds by HPLC separation and the simultaneous determination of their absolute configurations, we have developed camphorsultam dichlorophthalic acid (CSDP acid) for X-ray crystallography and 2-methoxy-2-(1-naphthyl)propionic acid (M,NP acid) for 1H NMR spectroscopy. In this review, the principles and applications of these X-ray and NMR methods are explained using mostly our own data. Chirality, 2008. © 2007 Wiley-Liss, Inc. [source] | |||||||||||||