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991.
Takeda M Kondo K Yamada M Sumikawa M Koizumi J Mashima T Katahira M 《International journal of biological macromolecules》2012,50(1):236-244
A sheath-forming sulfa oxidizer, Thiothrix nivea, was mixotrophically cultured in a medium supplemented with acetic acid and sodium disulfide. Its sheath, a microtube-like extracellular supermolecule, was prepared by selectively removing the cells with lysozyme, sodium dodecyl sulfate, and sodium hydroxide. The sheath was not visibly affected by hydrazine treatment, suggesting that it is not a proteinous supermolecule. From the acid hydrolysate of the sheath, glucose and glucosamine were detected in an approximate molar ratio of 1:1. Three other saccharic compounds were detected and recovered by HPLC as fluorescent derivatives prepared by reaction with 4-aminobenzoic acid ethyl ester. Nuclear magnetic resonance (NMR) analysis suggested that one of the derivatives was derived from an unidentified deoxypentose. NMR analysis for the other 2 derivatives showed that they were derived from β-1,4-linked disaccharides and tetrasaccharides, which were composed of glucose and glucosamine. The sheath was readily broken down by weak HCl treatment, releasing an unidentified deoxypentose and polymer. Chemical analysis showed the presence of β-1,4-linked d-Glcp and d-GlcNp in the polymer. NMR analysis revealed that the polymer had a repeating unit of →4)-d-Glcp-(β1→4)-d-GlcNp-(β1→. The solid-state 1D-13C NMR spectrum of the polymer in N-acetylated form supported this result. The molecular weight of the polymer was estimated to be 8.2 × 104 by size exclusion chromatography. Based on these results, the sheath of T. nivea is hypothesized to be assembled from alternately β-1,4-linked glucosaminoglucan grafted with unidentified deoxypentose. 相似文献
992.
Omata N Murata T Narita K Maruoka N Mitsuya H Mita K Nishimoto T Sato M Wada Y 《Neuro endocrinology letters》2012,33(1):1-2
The effect of antidepressants and mood stabilizers on serum levels of adiponectin was investigated. Fluvoxamine (30 and 50?mg/kg/day) or lithium (40 and 60?mg/kg/day) was dissolved in distilled water and administered orally to rats every day for 4 weeks. Fluvoxamine (50 mg/kg/day) alone significantly elevated the serum level of adiponectin, but no significant difference was found between other drug-treated groups and the control group. This difference of these drugs' effectiveness on serum adiponectin might contribute to their differences of action mechanisms and therapeutic effects. 相似文献
993.
Wnt5a-Ror2 signaling between osteoblast-lineage cells and osteoclast precursors enhances osteoclastogenesis 总被引:2,自引:0,他引:2
Maeda K Kobayashi Y Udagawa N Uehara S Ishihara A Mizoguchi T Kikuchi Y Takada I Kato S Kani S Nishita M Marumo K Martin TJ Minami Y Takahashi N 《Nature medicine》2012,18(3):405-412
The signaling molecule Wnt regulates bone homeostasis through β-catenin-dependent canonical and β-catenin-independent noncanonical pathways. Impairment of canonical Wnt signaling causes bone loss in arthritis and osteoporosis; however, it is unclear how noncanonical Wnt signaling regulates bone resorption. Wnt5a activates noncanonical Wnt signaling through receptor tyrosine kinase-like orphan receptor (Ror) proteins. We showed that Wnt5a-Ror2 signaling between osteoblast-lineage cells and osteoclast precursors enhanced osteoclastogenesis. Osteoblast-lineage cells expressed Wnt5a, whereas osteoclast precursors expressed Ror2. Mice deficient in either Wnt5a or Ror2, and those with either osteoclast precursor-specific Ror2 deficiency or osteoblast-lineage cell-specific Wnt5a deficiency showed impaired osteoclastogenesis. Wnt5a-Ror2 signals enhanced receptor activator of nuclear factor-κB (RANK) expression in osteoclast precursors by activating JNK and recruiting c-Jun on the promoter of the gene encoding RANK, thereby enhancing RANK ligand (RANKL)-induced osteoclastogenesis. A soluble form of Ror2 acted as a decoy receptor of Wnt5a and abrogated bone destruction in mouse arthritis models. Our results suggest that the Wnt5a-Ror2 pathway is crucial for osteoclastogenesis in physiological and pathological environments and represents a therapeutic target for bone diseases, including arthritis. 相似文献
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996.
Miki Daisuke Kobayashi Yuki Okada Tomoya Miyamoto Tatuso Takei Nobuyuki Sekino Yuko Koganezawa Noriko Shirao Tomoaki Saito Yumiko 《Neurochemical research》2019,44(7):1736-1744
Neurochemical Research - Recent advances in human induced pluripotent stem cells (hiPSCs) offer new possibilities for biomedical research and clinical applications. Neurons differentiated from... 相似文献
997.
Tadaatsu Hanadate Masaki Tomishima Nobuyuki Shiraishi Daisuke Tanabe Hiroshi Morikawa David Barrett Satoru Matsumoto Kazumi Ohtomo Katsuyuki Maki 《Bioorganic & medicinal chemistry letters》2009,19(5):1465-1468
Sordarin is a unique natural product antifungal agent that is an inhibitor of elongation factor 2. To improve biological activity, we synthesized various compounds by novel modification of the aglycone, sordaricin. As a result, we have discovered the novel sordarin derivative FR290581. This compound exhibited superior activity and a good pharmacokinetic profile, and also displayed good in vivo activity against Candida albicans. 相似文献
998.
The aims of this randomized observational case control study were to quantify fixation behavior during standard automated perimetry (SAP) with different fixation targets and to evaluate the relationship between fixation behavior and threshold variability at each test point in healthy young participants experienced with perimetry. SAP was performed on the right eyes of 29 participants using the Octopus 900 perimeter, program 32, dynamic strategy. The fixation targets of Point, Cross, and Ring were used for SAP. Fixation behavior was recorded using a wearable eye-tracking glass. All participants underwent SAP twice with each fixation target in a random fashion. Fixation behavior was quantified by calculating the bivariate contour ellipse area (BCEA) and the frequency of deviation from the fixation target. The BCEAs (deg2) of Point, Cross, and Ring targets were 1.11, 1.46, and 2.02, respectively. In all cases, BCEA increased significantly with increasing fixation target size (p < 0.05). The logarithmic value of BCEA demonstrated the same tendency (p < 0.05). A positive correlation was identified between fixation behavior and threshold variability for the Point and Cross targets (ρ = 0.413–0.534, p < 0.05). Fixation behavior increased with increasing fixation target size. Moreover, a larger fixation behavior tended to be associated with a higher threshold variability. A small fixation target is recommended during the visual field test. 相似文献
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1000.
Low‐intensity pulsed ultrasound stimulation promotes osteoblast differentiation through hedgehog signaling 下载免费PDF全文