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81.
Bärbel Ulmer Cathrin Hagenlocher Silke Schmalholz Sabrina Kurz Axel Schweickert Ayelet Kohl Lee Roth Dalit Sela-Donenfeld Martin Blum 《Cell reports》2013,3(3):615-621
Highlights? Cnn2 is expressed in NCCs and required for their migration in frogs and chicks ? Cnn2 is inactivated by noncanonical Wnt signaling ? Loss of Cnn2 causes a switch from cortical actin to central stress fibers ? Cnn2 polarizes the actin cytoskeleton downstream of PCP 相似文献
82.
Simon Glerup Maria Lume Ditte Olsen Jens R. Nyengaard Christian B. Vaegter Camilla Gustafsen Erik I. Christensen Mads Kjolby Anders Hay-Schmidt Dirk Bender Peder Madsen Mart Saarma Anders Nykjaer Claus M. Petersen 《Cell reports》2013,3(1):186-199
Highlights? SorLA is a sorting receptor for GDNF and its signaling receptors GFRa1 and RET ? The SorLA/GFRa1 complex targets GDNF for lysosomal degradation, while GFRa1 is recycled ? SorLA/GFRa1 targets RET for endocytosis and influences GDNF-induced neurotrophic effects ? SorLA knockout mice display altered dopaminergic function and an ADHD-like phenotype 相似文献
83.
Comparative Genome Analysis Provides Insights into the Pathogenicity of Flavobacterium psychrophilum
Daniel Castillo Rói Hammershaimb Christiansen Inger Dalsgaard Lone Madsen Romilio Espejo Mathias Middelboe 《PloS one》2016,11(4)
Flavobacterium psychrophilum is a fish pathogen in salmonid aquaculture worldwide that causes cold water disease (CWD) and rainbow trout fry syndrome (RTFS). Comparative genome analyses of 11 F. psychrophilum isolates representing temporally and geographically distant populations were used to describe the F. psychrophilum pan-genome and to examine virulence factors, prophages, CRISPR arrays, and genomic islands present in the genomes. Analysis of the genomic DNA sequences were complemented with selected phenotypic characteristics of the strains. The pan genome analysis showed that F. psychrophilum could hold at least 3373 genes, while the core genome contained 1743 genes. On average, 67 new genes were detected for every new genome added to the analysis, indicating that F. psychrophilum possesses an open pan genome. The putative virulence factors were equally distributed among isolates, independent of geographic location, year of isolation and source of isolates. Only one prophage-related sequence was found which corresponded to the previously described prophage 6H, and appeared in 5 out of 11 isolates. CRISPR array analysis revealed two different loci with dissimilar spacer content, which only matched one sequence in the database, the temperate bacteriophage 6H. Genomic Islands (GIs) were identified in F. psychrophilum isolates 950106-1/1 and CSF 259–93, associated with toxins and antibiotic resistance. Finally, phenotypic characterization revealed a high degree of similarity among the strains with respect to biofilm formation and secretion of extracellular enzymes. Global scale dispersion of virulence factors in the genomes and the abilities for biofilm formation, hemolytic activity and secretion of extracellular enzymes among the strains suggested that F. psychrophilum isolates have a similar mode of action on adhesion, colonization and destruction of fish tissues across large spatial and temporal scales of occurrence. Overall, the genomic characterization and phenotypic properties may provide new insights to the mechanisms of pathogenicity in F. psychrophilum. 相似文献
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85.
Urokinase links plasminogen activation and cell adhesion by cleavage of the RGD motif in vitronectin 下载免费PDF全文
Valentina De Lorenzi Gian Maria Sarra Ferraris Jeppe B Madsen Michela Lupia Peter A Andreasen Nicolai Sidenius 《EMBO reports》2016,17(7):982-998
Components of the plasminogen activation system including urokinase (uPA), its inhibitor (PAI‐1) and its cell surface receptor (uPAR) have been implicated in a wide variety of biological processes related to tissue homoeostasis. Firstly, the binding of uPA to uPAR favours extracellular proteolysis by enhancing cell surface plasminogen activation. Secondly, it promotes cell adhesion and signalling through binding of the provisional matrix protein vitronectin. We now report that uPA and plasmin induces a potent negative feedback on cell adhesion through specific cleavage of the RGD motif in vitronectin. Cleavage of vitronectin by uPA displays a remarkable receptor dependence and requires concomitant binding of both uPA and vitronectin to uPAR. Moreover, we show that PAI‐1 counteracts the negative feedback and behaves as a proteolysis‐triggered stabilizer of uPAR‐mediated cell adhesion to vitronectin. These findings identify a novel and highly specific function for the plasminogen activation system in the regulation of cell adhesion to vitronectin. The cleavage of vitronectin by uPA and plasmin results in the release of N‐terminal vitronectin fragments that can be detected in vivo, underscoring the potential physiological relevance of the process. 相似文献
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87.
Blimp-1-Dependent IL-10 Production by Tr1 Cells Regulates TNF-Mediated Tissue Pathology 总被引:1,自引:0,他引:1
Marcela Montes de Oca Rajiv Kumar Fabian de Labastida Rivera Fiona H Amante Meru Sheel Rebecca J. Faleiro Patrick T. Bunn Shannon E. Best Lynette Beattie Susanna S. Ng Chelsea L. Edwards Werner Muller Erika Cretney Stephen L. Nutt Mark J. Smyth Ashraful Haque Geoffrey R. Hill Shyam Sundar Axel Kallies Christian R. Engwerda 《PLoS pathogens》2016,12(1)
Tumor necrosis factor (TNF) is critical for controlling many intracellular infections, but can also contribute to inflammation. It can promote the destruction of important cell populations and trigger dramatic tissue remodeling following establishment of chronic disease. Therefore, a better understanding of TNF regulation is needed to allow pathogen control without causing or exacerbating disease. IL-10 is an important regulatory cytokine with broad activities, including the suppression of inflammation. IL-10 is produced by different immune cells; however, its regulation and function appears to be cell-specific and context-dependent. Recently, IL-10 produced by Th1 (Tr1) cells was shown to protect host tissues from inflammation induced following infection. Here, we identify a novel pathway of TNF regulation by IL-10 from Tr1 cells during parasitic infection. We report elevated Blimp-1 mRNA levels in CD4+ T cells from visceral leishmaniasis (VL) patients, and demonstrate IL-12 was essential for Blimp-1 expression and Tr1 cell development in experimental VL. Critically, we show Blimp-1-dependent IL-10 production by Tr1 cells prevents tissue damage caused by IFNγ-dependent TNF production. Therefore, we identify Blimp-1-dependent IL-10 produced by Tr1 cells as a key regulator of TNF-mediated pathology and identify Tr1 cells as potential therapeutic tools to control inflammation. 相似文献
88.
Anne-Marie Lundsgaard Jacob B. Holm Kim A. Sjøberg Kirstine N. Bojsen-Møller Lene S. Myrmel Even Fjære Benjamin A.H. Jensen Trine S. Nicolaisen Janne R. Hingst Sine L. Hansen Sophia Doll Philip E. Geyer Atul S. Deshmukh Jens J. Holst Lise Madsen Karsten Kristiansen Jørgen F.P. Wojtaszewski Erik A. Richter Bente Kiens 《Cell metabolism》2019,29(1):50-63.e4
89.
Objective: To evaluate the long‐term weight loss maintenance after 2 to 4 years in severely obese subjects after a lifestyle intervention at a weight loss camp in Denmark. Research Methods and Procedures: In a retrospective follow‐up study, we assessed weight loss after 21 weeks of treatment at a weight loss camp, weight loss maintenance after 2 to 4 years, and numbers of subjects with a weight loss maintenance of ≥10% of a total number of 435 severely obese adults participating in an intensive lifestyle intervention with a primary focus on physical activity. Results: We obtained follow‐up data of 249 subjects (180 women and 69 men) with an initial body weight of 142 ± 32 kg. After 21 weeks at the camp, the subjects had reduced their body weight with a mean of 21.9 ± 13 kg (corresponding to a 15% weight loss). The average weight loss maintenance was 5.3% at a follow‐up after 2 to 4 years, and 28.3% had maintained a weight loss above 10% after 4 years of follow‐up. Discussion: Weight loss camps are a relatively new commercial approach in treating severely obese subjects. However, the results demonstrate that even with a multidisciplinary intensive setting with focus on diet, exercise, and psychological counseling, only 28% had maintained a weight loss above 10% after 4 years. This emphasizes that obesity is a chronic condition that needs additional strategies after a weight loss intervention in the efforts to maintain a sufficient weight loss. 相似文献
90.