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351.
Stephen D. Robinson Louise E. Reynolds Vassiliki Kostourou Andrew R. Reynolds Rita Gra?a da Silva Bernardo Tavora Marianne Baker John F. Marshall Kairbaan M. Hodivala-Dilke 《The Journal of biological chemistry》2009,284(49):33966-33981
Both vascular endothelial growth factor receptors (VEGFR) and integrins are major regulators of VEGF-induced angiogenesis. Previous work has shown that β3 integrin can regulate negatively VEGFR2 expression. Here we show that β3 integrin can regulate negatively VEGF-mediated angiogenesis by limiting the interaction of the co-receptor NRP1 (neuropilin-1) with VEGFR2. In the presence of αvβ3 integrin, NRP1 contributed minimally to VEGF-induced angiogenic processes in vivo, ex vivo, and in vitro. Conversely, when β3 integrin expression is absent or low or its function is blocked with RGD-mimetic inhibitors, VEGF-mediated responses became NRP1-dependent. Indeed, combined inhibition of β3 integrin and NRP1 decreased VEGF-mediated angiogenic responses further than individual inhibition of these receptors. We also show that αvβ3 integrin can associate with NRP1 in a VEGF-dependent fashion. Our data suggest that β3 integrin may, in part, negatively regulate VEGF signaling by sequestering NRP1 and preventing it from interacting with VEGFR2. 相似文献
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doi: 10.1111/j.1741‐2358.2011.00491.x Assessing oral health promotion determinants in active Greek elderly Objective: To explore older adults’ patterns and risk behaviours to be invoked in the allocation of strategies to promote oral health. Background: Access to dental services is determined by factors that serve as barriers to or enablers of older adults’ behaviour and attitudes towards oral health. Appropriate oral health promotion activities are of particular importance among the elderly in altering oral health behaviour through education, prevention and health protection. Methods: A cross‐sectional study was conducted among 108 dentate elderly subjects. They were attending a University Prosthetic Dentistry Clinic in Greece as patients seeking treatment. Participants underwent a clinical examination and an interview. Results: Data extracted revealed that cost and no disease awareness were the most frequently mentioned barriers to regular dental visits. Most of the participants presented low level of income and education and reduced presence of adverse dental health symptoms compared with the actual oral health status. Besides some predisposing factors, enabling and need variables significantly affected access to dental care services, participants’ number of remaining teeth and as a consequence oral health status. Conclusion: Profiling older adults’ demographics, economic, social and cultural status and their attitudes and beliefs could further contribute in developing universal activities and strategies for oral health promotion so as ageing challenges are favoured. 相似文献
358.
Viennas E Gkantouna V Ioannou M Georgitsi M Rigou M Poulas K Patrinos GP Tzimas G 《Genomics》2012,100(2):93-101
National/ethnic mutation databases aim to document the genetic heterogeneity in various populations and ethnic groups worldwide. We have previously reported the development and upgrade of FINDbase (www.findbase.org), a database recording causative mutations and pharmacogenomic marker allele frequencies in various populations around the globe. Although this database has recently been upgraded, we continuously try to enhance its functionality by providing more advanced visualization tools that would further assist effective data querying and comparisons. We are currently experimenting in various visualization techniques on the existing FINDbase causative mutation data collection aiming to provide a dynamic research tool for the worldwide scientific community. We have developed an interactive web-based application for population-based mutation data retrieval. It supports sophisticated data exploration allowing users to apply advanced filtering criteria upon a set of multiple views of the underlying data collection and enables browsing the relationships between individual datasets in a novel and meaningful way. 相似文献
359.
D Georgiou V Toutountzoglou KW Muir D Hadjipavlou-Litina Y Elemes 《Bioorganic & medicinal chemistry》2012,20(17):5103-5109
The 1,3-dipolar cycloaddition to N-phenylmaleimide of azomethine ylides, generated in situ from sulfanyl-substituted imines of glycine esters, yields 5H-dihydro-pyrrolo products with syn diastereoselectivity. The syn (major) and anti (minor) products were isolated chromatographically and fully characterized by spectroscopic methods and in two cases also by X-ray analysis. The diastereomeric cycloadducts were tested for their antioxidant activity with good results. 相似文献
360.
Hamodrakas SJ Willis JH Iconomidou VA 《Insect biochemistry and molecular biology》2002,32(11):1577-1583
The nature of the interaction of insect cuticular proteins and chitin is unknown even though about half of the cuticular proteins sequenced thus far share a consensus region that has been predicted to be the site of chitin binding. We previously predicted the preponderance of beta-pleated sheet in the consensus region and proposed its responsibility for the formation of helicoidal cuticle (Iconomidou et al., Insect Biochem. Mol. Biol. 29 (1999) 285). Consequently, we have also verified experimentally the abundance of antiparallel beta-pleated sheet in the structure of cuticle proteins (Iconomidou et al., Insect Biochem. Mol. Biol. 31 (2001) 877). In this work, based on sequence and secondary structure similarity of cuticle proteins, and especially that of the consensus motif, to that of bovine plasma retinol binding protein (RBP), we propose by homology modelling an antiparallel beta-sheet half-barrel structure as the basic folding motif of cuticle proteins. This folding motif may provide the template for elucidating cuticle protein-chitin interactions in detail and reveal the precise geometrical formation of cuticle's helicoidal architecture. This predicted motif is another example where nature utilizes an almost flat protein surface covered by aromatic side chains to interact with the polysaccharide chains of chitin. 相似文献