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31.
Cystic fibrosis (CF) airway epithelium is constantly subjected to injury events due to chronic infection and inflammation. Moreover, abnormalities in CF airway epithelium repair have been described and contribute to the lung function decline seen in CF patients. In the last past years, it has been proposed that anoctamin 1 (ANO1), a Ca2 +-activated Cl? channel, might offset the CFTR deficiency but this protein has not been characterized in CF airways. Interestingly, recent evidence indicates a role for ANO1 in cell proliferation and tumor growth. Our aims were to study non-CF and CF bronchial epithelial repair and to determine whether ANO1 is involved in airway epithelial repair. Here, we showed, with human bronchial epithelial cell lines and primary cells, that both cell proliferation and migration during epithelial repair are delayed in CF compared to non-CF cells. We then demonstrated that ANO1 Cl? channel activity was significantly decreased in CF versus non-CF cells. To explain this decreased Cl? channel activity in CF context, we compared ANO1 expression in non-CF vs. CF bronchial epithelial cell lines and primary cells, in lung explants from wild-type vs. F508del mice and non-CF vs. CF patients. In all these models, ANO1 expression was markedly lower in CF compared to non-CF. Finally, we established that ANO1 inhibition or overexpression was associated respectively with decreases and increases in cell proliferation and migration. In summary, our study demonstrates involvement of ANO1 decreased activity and expression in abnormal CF airway epithelial repair and suggests that ANO1 correction may improve this process.  相似文献   
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For the first time in Belgium and Luxembourg, the diversity and taxonomy of 95 cyanobacterial strains isolated from freshwater blooms were assessed by the comparison of phenotypes and partial 16S rRNA gene sequences. The results showed the high diversity of nanoplanktonic, picoplanktonic, and benthic–periphytic cyanobacteria accompanying the main bloom‐forming taxa. Indeed, besides 15 morphotypes of bloom‐forming taxa, seven non‐bloom‐forming planktonic morphotypes and 11 morphotypes from benthic–periphytic taxa were isolated in culture from the plankton samples of 35 water bodies. The bloom‐forming strains belonged to the genera Microcystis, Woronichinia, Planktothrix, Anabaena, and Aphanizomenon, whereas the other strains isolated from the same samples were assigned to the nanoplanktonic Aphanocapsa, Aphanothece, Snowella, and Pseudanabaena; to the picoplanktonic Cyanobium; and to the benthic–periphytic Geitlerinema, Komvophoron, Leptolyngbya, Lyngbya, Phormidium, Calothrix, Nostoc, and Trichormus. The results supported both the polyphyletism of genera such as Aphanocapsa, Aphanothece, Leptolyngbya, Geitlerinema, Anabaena, and Aphanizomenon as well as the validity of genera such as Microcystis, Planktothrix, and Pseudanabaena with gas vesicles and cells constricted at the cross wall. The results obtained showed the close relationship between Snowella and Woronichinia for which very few sequences exist. The first sequence of Komvophoron appeared poorly related to other available cyanobacterial sequences. Although in a few cases a good agreement existed between phenotypic and genotypic features, there was generally a discrepancy. Strains with identical morphotypes show small differences in the 16S rRNA sequences, which might be related to the different chemical properties of their habitats. The results showed the importance of the polyphasic approach in order to improve the taxonomy of cyanobacteria.  相似文献   
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The Annual bioProcessUK Conference has acted as the key networking event for bioprocess scientists and engineers in the UK for the past 10 years. The following article is a report from the sessions that focused on continuous bioprocessing during the 10th Annual bioProcessUK Conference (London, December 2013). These sessions were organized by the ‘EPSRC Centre for Innovative Manufacturing in Emergent Macromolecular Therapies’ hosted at University College London. A plenary lecture and workshop provided a forum for participants to debate topical issues in roundtable discussions with industry and academic experts from institutions such as Genzyme, Janssen, Novo Nordisk, Pfizer, Merck, GE Healthcare and University College London. The aim of these particular sessions was to understand better the challenges and opportunities for continuous bioprocessing in the bioprocessing sector.  相似文献   
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The most prominent protein ofPolygonatum multiflorum (common Solomon's seal) rhizomes has been identified as a mannose-binding lectin. Analysis of the purified lectin demonstrated that it is a tetramer of four identical subunits of 14 kDa. Molecular cloning further revealed that the lectin from this typical Liliaceae species belongs to the superfamily of monocot mannose-binding proteins. Screening of cDNA libraries constructed with RNA isolated from buds, leaves and flowers ofP. multiflorum also yielded cDNA clones encoding a protein, which contains two tandemly arranged domains with an obvious sequence homology to the mannose-binding lectins. Molecular modelling of thePolygonatum lectin and lectin-related protein indicated that the three-dimensional structure of both proteins strongly resembles that of the snowdrop lectin. In addition, this approach suggested that the presumed carbohydrate-binding sites of the lectin can accommodate a mannose residue whereas most of the carbohydratebinding sites of the lectin-related protein cannot.Abbreviations GNA Galanthus nivalis agglutinin - HCA hydrophobic cluster analysis - LECPMA cDNA clone encoding PMA - PM30 30 kDa protein isolated fromPolygonatum multiforum - PMA Polygonatum multiflorum agglutinin - PMLRP Polygonatum multiflorum lectin-related protein  相似文献   
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A new strain of strictly anaerobic fungi was isolated from the rumen of sheep. This strain is characterized by a polycentric thallus, an extensive and polynuclear rhizomycelium, polyflagellated zoospores with gamma particle-like bodies. We propose to assign this strain in a new species: Neocallimastix joyonii.  相似文献   
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Lactoferrin is a member of the transferrin family of iron-binding glycoproteins that is abundantly expressed and secreted from glandular epithelial cells. In secretions, such as milk and fluids of the intestinal tract, lactoferrin is an important component of the first line of host defence. During the inflammatory process, lactoferrin, a prominent component of the secondary granules of neutrophils (PMNs), is released in infected tissues and in blood and then it is rapidly cleared by the liver. In addition to the antimicrobial properties of lactoferrin, a set of studies has focused on its ability to modulate the inflammatory process and the overall immune response. Though many in vitro and in vivo studies report clear regulation of the immune response and protective effect against infection and septic shock by lactoferrin, elucidation of all the cellular and molecular mechanisms of action is far from being achieved. At the cellular level, lactoferrin modulates the migration, maturation and function of immune cells. At the molecular level and in addition to iron binding, interactions of lactoferrin with a plethora of compounds, either soluble or membrane molecules, account for its modulatory properties. This paper reviews our current understanding of the cellular and molecular mechanisms that explain the regulatory properties of lactoferrin in host defence.  相似文献   
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