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61.
Junctional adhesion molecules (JAMs) of the immunoglobulin superfamily are important in the control of vascular permeability and leukocyte transmigration across endothelial-cell surfaces, by engaging in homophilic, heterophilic and lateral interactions. Through their localization on the endothelial-cell surface and expression by platelets, JAMs contribute to adhesive interactions with circulating leukocytes and platelets. Antibody-blocking studies and studies using genetically modified mice have implicated these functions of JAMs in the regulation of leukocyte recruitment to sites of inflammation and ischaemia-reperfusion injury, in growth-factor-mediated angiogenesis, atherogenesis and neointima formation. The comparison of different JAM-family members and animal models, however, shows that the picture remains rather complex. This Review summarizes recent progress and future directions in understanding the role of JAMs as 'gate keepers' in inflammation and vascular pathology. 相似文献
62.
Parallel declines in survival of adult Northern Fulmars Fulmarus glacialis at colonies in Scotland and Ireland 下载免费PDF全文
Line S. Cordes Helen E. Hedworth David Cabot Maurice Cassidy Paul M. Thompson 《Ibis》2015,157(3):631-636
Assessing broad‐scale changes in seabird populations across the North Atlantic requires an integration of available datasets to understand the spatial extent of potential drivers and demographic change. Here, we compared survival of Northern Fulmars Fulmarus glacialis from a Scottish and an Irish colony from 1974 to 2009. Despite lower recapture probabilities of monel‐ringed Irish birds compared with colour‐ringed Scottish birds, survival probability decreased at both colonies. The extent to which the decline in survival is related to density‐dependent processes or other external drivers remains uncertain, but our results suggest that these changes in survival are possibly indicative of larger‐scale processes and are not confined to local colony dynamics. 相似文献
63.
Lohse B Kristensen JL Kristensen LH Agger K Helin K Gajhede M Clausen RP 《Bioorganic & medicinal chemistry》2011,19(12):3625-3636
Methylated lysines are important epigenetic marks. The enzymes involved in demethylation have recently been discovered and found to be involved in cancer development and progression. Despite the relative recent discovery of these enzymes a number of inhibitors have already appeared. Most of the inhibitors are either previously reported inhibitors of related enzymes or compounds derived from these. Development in terms of selectivity and potency is still pertinent. Several reports on the development of functional assays have been published. 相似文献
64.
Anina Ritterband-Rosenbaum Mark S Christensen Mette Kliim-Due Line Z Petersen Betina Rasmussen Jens B Nielsen 《BMC neurology》2011,11(1):150
Background
Children diagnosed with spastic Cerebral Palsy (CP) often show perceptual and cognitive problems, which may contribute to their functional deficit. Here we investigated if altered ability to determine whether an observed movement is performed by themselves (sense of agency) contributes to the motor deficit in children with CP. 相似文献65.
Esposito M Piatti S Hofmann L Frontali L Delahodde A Rinaldi T 《FEMS yeast research》2011,11(1):60-71
The proteasomal lid subunit Rpn11 is essential for maintaining a correct cell cycle and mitochondrial morphology in Saccharomyces cerevisiae. In this paper, we show that the rpn11-m1 mutant has a peculiar cell cycle defect reminiscent of mutants defective in the FEAR pathway that delay the release of the Cdc14 protein phosphatase from the nucleolus. We analyzed the rpn11-m1 phenotypes and found that overexpression of Cdc14 suppresses all the rpn11-m1 defects, including the mitochondrial ones. Suppression by Cdc14 of the rpn11-m1 mitochondrial morphology defect reveals an uncharacterized connection between mitochondrial and cell cycle events. Interestingly, the overexpression of Cdc14 also partially restores the tubular network in an Δmmm2 strain, which lacks a mitochondrial protein belonging to the complex necessary to anchor the mitochondrion to the actin cytoskeleton. Altogether our findings indicate, for the first time, a cross-talk between the cell cycle and mitochondrial morphology. 相似文献
66.
Laerdahl JK Korvald H Nilsen L Dahl-Michelsen K Rognes T Bjørås M Alseth I 《DNA Repair》2011,10(3):296-305
Mutagenic and cytotoxic apurinic/apyrimidinic (AP) sites are among the most frequent lesions in DNA. Repair of AP sites is initiated by AP endonucleases and most organisms possess two or more of these enzymes. Saccharomyces cerevisiae has AP endonuclease 1 (Apn1) as the major enzymatic activity with AP endonuclease 2 (Apn2) being an important backup. Schizosaccharomyces pombe also encodes two potential AP endonucleases, and Apn2 has been found to be the main repair activity, while Apn1 has no, or only a limited role in AP site repair. Here we have identified a new 5' exon (exon 1) in the apn1 gene and show that the inactivity of S. pombe Apn1 is due to a nonsense mutation in the fifth codon of this new exon. Reversion of this mutation restored the AP endonuclease activity of S. pombe Apn1. Interestingly, the apn1 nonsense mutation was only found in laboratory strains derived from L972 h(-) and not in unrelated isolates of S. pombe. Since all S. pombe laboratory strains originate from L972 h(-), it appears that all experiments involving S. pombe have been conducted in an apn1(-) mutant strain with a corresponding DNA repair deficiency. These observations have implications both for future research in S. pombe and for the interpretation of previously conducted epistatis analysis. 相似文献
67.
Bittner L Payri CE Maneveldt GW Couloux A Cruaud C de Reviers B Le Gall L 《Molecular phylogenetics and evolution》2011,61(3):697-713
Systematics of the red algal order Corallinales has a long and convoluted history. In the present study, molecular approaches were used to assess the phylogenetic relationships based on the analyses of two datasets: a large dataset of SSU sequences including mainly sequences from GenBank; and a combined dataset including four molecular markers (two nuclear: SSU, LSU; one plastidial: psbA; and one mitochondrial: COI). Phylogenetic analyses of both datasets re-affirmed the monophyly of the Corallinales as well as the two families (Corallinaceae and Hapalidiaceae) currently recognized within the order. Three of the four subfamilies of the Corallinaceae (Corallinoideae, Lithophylloideae, Metagoniolithoideae) were also resolved as a monophyletic lineage whereas members of the Mastophoroideae were resolved as four distinct lineages. We therefore propose to restrict the Mastophoroideae to the genera Mastophora, Metamastophora, and possibly Lithoporella in the aim of rendering this subfamily monophyletic. In addition, our phylogenies resolved the genus Hydrolithon in two unrelated lineages, one containing the generitype Hydrolithon reinboldii and the second containing Hydrolithon onkodes, which used to be the generitype of the now defunct genus Porolithon. We therefore propose to resurrect the genus Porolithon for the second lineage encompassing those species with primarily monomerous thalli, and trichocyte arrangements in large pustulate horizontal rows. Moreover, our phylogenetic analyses revealed the presence of cryptic diversity in several taxa, shedding light on the need for further studies to better circumscribe species frontiers within the diverse order Corallinales, especially in the genera Mesophyllum and Neogoniolithon. 相似文献
68.
69.
Discrimination and Characterization of Two Mediterranean Species from the Laurencia Complex (Rhodomelacea) Using an NMR‐Based Metabolomic Approach 下载免费PDF全文
Sylvain Sutour Hélène Esselin Ange Bighelli Joseph Casanova Line Le Gall Félix Tomi 《化学与生物多样性》2017,14(11)
Generic and specific determination among the Laurencia complex is a challenging task. DNA barcoding combined with phenotypic investigations are mandatory for species differentiation. In this study, two morphologically different members of the Laurencia complex were investigated using untargeted 1H‐NMR‐based metabolomics. Twenty‐one population samples were collected in order to evaluate both temporal and geographical homogeneity. Data obtained from 1H‐NMR analysis followed by statistical analysis allowed a clear separation of all the samples into two groups. DNA mitochondrial tests confirmed this pattern and identified the two species as Laurenciella sp. and Laurencia obtusa. In addition, metabolites responsible of this discrimination were investigated directly in crude extracts by 13C‐NMR using an in‐house computer‐assisted method. The combination of both untargeted (1H) and targeted (13C) NMR‐based metabolomic approaches proves to be a powerful and complementary approach to discriminate species from the Laurencia complex. 相似文献
70.