Publications by authors named "Takayuki Satou"

Objective And Design: To evaluate the potency of RORγt blockade for treatment of Inflammatory Bowel Disease (IBD), the efficacy of TAK-828F, a novel RORγt inverse agonist, in anti-TNF-α mAb non-responsive mouse colitis model and effect of TAK-828F on IL-17 production in peripheral mononuclear blood cells (PBMCs) of anti-TNF-α naive and treatment-failure patients of IBD was investigated.

Methods And Results: The colitis model showed Th17-dependent pathogenicity and response to anti-IL-12/23p40 monoclonal antibody (mAb), but no response to anti-TNF-α mAb. In the model, TAK-828F, at oral dosages of 1 and 3 mg/kg, inhibited progression of colitis and reduced the immune reaction that characterize Th17 cells.

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We tested the hypothesis that in shallow, eutrophic Lake Kasumigaura, the concentration of particulate phosphorus (PP) is controlled by biogenic P (P in living or dead phytoplankton and bacterial cells), rather than by resuspension of inorganic P in sediment. Increases in wind velocity and turbidity were associated with bottom shear stress exceeding the critical value for the lake (τc=0.15Nm(-2)); this increased turbidity was due to sediment resuspension.

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We investigated spatial and temporal variations in bacterial community structures as well as the presence of three functional proteolytic enzyme genes in the sediments of a hypereutrophic freshwater lake in order to acquire an insight into dynamic links between bacterial community structures and proteolytic functions. Bacterial communities determined from 16S rRNA gene clone libraries markedly changed bimonthly, rather than vertically in the sediment cores. The phylum Firmicutes dominated in the 4-6 cm deep sediment layer sample after August in 2007, and this correlated with increases in interstitial ammonium concentrations (p < 0.

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Incubation experiments using filtered waters from Lake Kasumigaura were conducted to examine bacterial contribution to a dissolved organic carbon (DOC) pool. Bacterial abundance, bacterial production, concentrations of DOC, total dissolved amino acids (TDAA), and total dissolved neutral sugars (TDNS) were monitored during the experiments. Bacterial production during the first few days was very high (20 to 35 μg C liter(-1) day(-1)), accounting for 40 to 70% of primary production.

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The reagent-free mineralization of dissolved organic matter (DOM) in river water was achieved within 1 min using a lamp-pass-through photoreactor containing a narrow reaction tube (2 mm i.d.) passing through a 40 W mercury lamp.

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Differences in biogenic phosphorus (P) compounds between sediment and suspended particles in aquatic environments are important for understanding the mechanisms of internal P loading, but these differences are still unknown. We used solution-state (31)P-nuclear magnetic resonance spectroscopy ((31)P NMR) with NaOH-ethylenediaminetetraacetic extraction to detect the multiple P compounds in suspended particles and sediment in the eutrophic Lake Kasumigaura, including orthophosphate monoesters, orthophosphate diesters, pyrophosphate, and polyphosphate. We tested the hypothesis that there is a significant difference between these groups in suspended particles and sediment.

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The free-living, cosmopolitan, freshwater betaproteobacterial bacterioplankton genus Polynucleobacter was detected in different years in 11 lakes of varying types and a river using the size-exclusion assay method (SEAM). Of the 350 strains isolated, 228 (65.1%) were affiliated with the Polynucleobacter subclusters PnecC (30.

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