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71.
Ishikawa T Terai S Urata Y Marumoto Y Aoyama K Murata T Mizunaga Y Yamamoto N Nishina H Shinoda K Sakaida I 《Cell and tissue research》2007,327(3):463-470
We previously reported that fibroblast growth factor 2 (FGF2) facilitated the differentiation of transplanted bone marrow
cells (BMCs) into hepatocytes. Our earlier study also demonstrated that administration of FGF2 in combination with bone marrow
transplantation (BMT) synergistically activated tumor necrosis factor-alpha signaling and significantly improved liver function
and prognosis more than BMT alone. However, the way that it affected the extracellular matrix remained unclear. Here, we investigated
the effect of FGF2 treatment together with BMT on liver fibrosis in mice treated with carbon tetrachloride (CCl4). Transplantation of BMCs and concurrent treatment with FGF2 caused a statistically significant reduction in CCl4-induced liver fibrosis that was accompanied by strong expression of matrix metalloproteinase 9 as compared with FGF2-only
treatment or BMT alone. Moreover, in this process, the proliferation of bone-marrow-derived cells was accelerated without
causing apoptosis. Thus, the administration of FGF2 in combination with BMT synergistically improves CCl4-induced liver fibrosis in mice. This treatment has the potential of being an effective therapy for patients with liver cirrhosis.
This study was supported by Grants-in-Aid for Scientific Research from the Japan Society for the Promotion of Science (nos. 16390211
and 16590597) and for translational research from the Ministry of Health, Labor and Welfare (H-trans-5 and H17-Special-015). 相似文献
72.
The methanol extract of Sophora flavescens, which is used in traditional Chinese medicine (sophorae radix), showed potent Na(+)-glucose cotransporter (SGLT) inhibitory activity. Our search for active components identified many well-known flavonoid antioxidants: kurarinone, sophoraflavanone G, kushenol K, and kushenol N. 相似文献
73.
Objective: Various factors may be associated with edentulism in elderly people. Association of total tooth loss with smoking, alcohol intake and nutrition in non‐institutionalised elderly Japanese was assessed utilising national database. Materials and methods: Records of independent surveys, the Survey of Dental Diseases (SDD) and the National Nutrition Survey (NNS) in 1999 were electronically linked using the household identification number. Results: Among the records of 6903 subjects in the SDD and 12 763 subjects in the NNS, 6805 records were successfully linked. Overall, prevalence of total tooth loss in adults was very similar in males and females at approximately 7.0%, and the smoking rate was 47.6% and 9.9% respectively. Total tooth loss was a rare phenomenon (<2%) in age groups of <60 years. According to the multiple logistic regression analysis involving 2200 subjects aged 60 years or older, significant variables were age, current smokers and vitamin C intake in males, and age and current smokers in females. The variable for current drinkers was significant in females but the odds ratio was <1.0. No significant relationship was detected with respect to former smokers and drinkers, body mass index, vitamin E intake and blood glucose level. Conclusions: Current smoking was associated with total tooth loss, although smoking rate was low in females. Gender difference in the association was suggestive with respect to drinking alcohol and vitamin C intake. 相似文献
74.
Akira Ishio Takeshi Sasamura Tomonori Ayukawa Junpei Kuroda Hiroyuki O. Ishikawa Naoki Aoyama Kenjiroo Matsumoto Takuma Gushiken Tetsuya Okajima Tomoko Yamakawa Kenji Matsuno 《The Journal of biological chemistry》2015,290(1):505-519
Notch (N) is a transmembrane receptor that mediates the cell-cell interactions necessary for many cell fate decisions. N has many epidermal growth factor-like repeats that are O-fucosylated by the protein O-fucosyltransferase 1 (O-Fut1), and the O-fut1 gene is essential for N signaling. However, the role of the monosaccharide O-fucose on N is unclear, because O-Fut1 also appears to have O-fucosyltransferase activity-independent functions, including as an N-specific chaperon. Such an enzymatic activity-independent function could account for the essential role of O-fut1 in N signaling. To evaluate the role of the monosaccharide O-fucose modification in N signaling, here we generated a knock-in mutant of O-fut1 (O-fut1R245A knock-in), which expresses a mutant protein that lacks O-fucosyltransferase activity but maintains the N-specific chaperon activity. Using O-fut1R245A knock-in and other gene mutations that abolish the O-fucosylation of N, we found that the monosaccharide O-fucose modification of N has a temperature-sensitive function that is essential for N signaling. The O-fucose monosaccharide and O-glucose glycan modification, catalyzed by Rumi, function redundantly in the activation of N signaling. We also showed that the redundant function of these two modifications is responsible for the presence of N at the cell surface. Our findings elucidate how different forms of glycosylation on a protein can influence the protein''s functions. 相似文献
75.
Okazaki M Nimitkeatkai H Muramatsu T Aoyama H Ueno K Mizutani M Hirai N Kondo S Ohnishi T Todoroki Y 《Bioorganic & medicinal chemistry》2011,19(1):406-413
We developed abscinazole-E1 (Abz-E1), a specific inhibitor of abscisic acid (ABA) 8′-hydroxylase (CYP707A). This inhibitor was designed and synthesized as an enlarged analogue of uniconazole (UNI), a well-known plant growth retardant, which inhibits a gibberellin biosynthetic enzyme (ent-kaurene oxidase, CYP701A) as well as CYP707A. Our results showed that Abz-E1 functions as a potent inhibitor of CYP707A and a poor inhibitor of CYP701A both in vitro and in vivo. Abz-E1 application to plants resulted in improved desiccation tolerance and an increase in endogenous ABA. 相似文献
76.
Aoyama H Sugita K Nakamura M Aoyama A Salim MT Okamoto M Baba M Hashimoto Y 《Bioorganic & medicinal chemistry》2011,19(8):2675-2687
We identified a fused heteroaromatic amido structure based on the phenanthridine skeleton as a superior scaffold for candidate drugs with potent anti-HCV activity. Among the compounds synthesized, a phenanthridine analogue with a 1,3-dioxolyl group (24) possessed the most potent anti-HCV activity (EC(50) value: 50 nM), with acceptable cytotoxicity. The structural development and structure-activity relationships of these compounds are described. 相似文献
77.
Mitsui H Aoyama T Furu M Ito K Jin Y Maruyama T Kanaji T Fujimura S Sugihara H Nishiura A Otsuka T Nakamura T Toguchida J 《Arthritis research & therapy》2011,13(5):R146-13
Introduction
Osteoarthritis (OA) is a common cause of disability in older adults. We have previously reported that an agonist for subtypes EP2 of the prostaglandin E2 receptor (an EP2 agonist) promotes the regeneration of chondral and osteochondral defects. The purpose of the current study is to analyze the effect of this agonist on articular cartilage in a model of traumatic degeneration.Methods
The model of traumatic degeneration was established through transection of the anterior cruciate ligament and partial resection of the medial meniscus of the rabbits. Rabbits were divided into 5 groups; G-S (sham operation), G-C (no further treatment), G-0, G-80, and G-400 (single intra-articular administration of gelatin hydrogel containing 0, 80, and 400 μg of the specific EP2 agonist, ONO-8815Ly, respectively). Degeneration of the articular cartilage was evaluated at 2 or 12 weeks after the operation.Results
ONO-8815Ly prevented cartilage degeneration at 2 weeks, which was associated with the inhibition of matrix metalloproteinase-13 (MMP-13) expression. The effect of ONO-8815Ly failed to last, and no effects were observed at 12 weeks after the operation.Conclusions
Stimulation of prostaglandin E2 (PGE2) via EP2 prevents degeneration of the articular cartilage during the early stages. With a system to deliver it long term, the EP2 agonist could be a new therapeutic tool for OA. 相似文献78.
Nonomura K Eiguchi M Nakano M Takashima K Komeda N Fukuchi S Miyazaki S Miyao A Hirochika H Kurata N 《PLoS genetics》2011,7(1):e1001265
The molecular mechanism for meiotic entry remains largely elusive in flowering plants. Only Arabidopsis SWI1/DYAD and maize AM1, both of which are the coiled-coil protein, are known to be required for the initiation of plant meiosis. The mechanism underlying the synchrony of male meiosis, characteristic to flowering plants, has also been unclear in the plant kingdom. In other eukaryotes, RNA-recognition-motif (RRM) proteins are known to play essential roles in germ-cell development and meiosis progression. Rice MEL2 protein discovered in this study shows partial similarity with human proline-rich RRM protein, deleted in Azoospermia-Associated Protein1 (DAZAP1), though MEL2 also possesses ankyrin repeats and a RING finger motif. Expression analyses of several cell-cycle markers revealed that, in mel2 mutant anthers, most germ cells failed to enter premeiotic S-phase and meiosis, and a part escaped from the defect and underwent meiosis with a significant delay or continued mitotic cycles. Immunofluorescent detection revealed that T7 peptide-tagged MEL2 localized at cytoplasmic perinuclear region of germ cells during premeiotic interphase in transgenic rice plants. This study is the first report of the plant RRM protein, which is required for regulating the premeiotic G1/S-phase transition of male and female germ cells and also establishing synchrony of male meiosis. This study will contribute to elucidation of similarities and diversities in reproduction system between plants and other species. 相似文献
79.
Dubouzet JG Maeda S Sugano S Ohtake M Hayashi N Ichikawa T Kondou Y Kuroda H Horii Y Matsui M Oda K Hirochika H Takatsuji H Mori M 《Plant biotechnology journal》2011,9(4):466-485
Approximately 20,000 of the rice-FOX Arabidopsis transgenic lines, which overexpress 13,000 rice full-length cDNAs at random in Arabidopsis, were screened for bacterial disease resistance by dip inoculation with Pseudomonas syringae pv. tomato DC3000 (Pst DC3000). The identities of the overexpressed genes were determined in 72 lines that showed consistent resistance after three independent screens. Pst DC3000 resistance was verified for 19 genes by characterizing other independent Arabidopsis lines for the same genes in the original rice-FOX hunting population or obtained by reintroducing the genes into ecotype Columbia by floral dip transformation. Thirteen lines of these 72 selections were also resistant to the fungal pathogen Colletotrichum higginsianum. Eight genes that conferred resistance to Pst DC3000 in Arabidopsis have been introduced into rice for overexpression, and transformants were evaluated for resistance to the rice bacterial pathogen, Xanthomonas oryzae pv. oryzae. One of the transgenic rice lines was highly resistant to Xanthomonas oryzae pv. oryzae. Interestingly, this line also showed remarkably high resistance to Magnaporthe grisea, the fungal pathogen causing rice blast, which is the most devastating rice disease in many countries. The causal rice gene, encoding a putative receptor-like cytoplasmic kinase, was therefore designated as BROAD-SPECTRUM RESISTANCE 1. Our results demonstrate the utility of the rice-FOX Arabidopsis lines as a tool for the identification of genes involved in plant defence and suggest the presence of a defence mechanism common between monocots and dicots. 相似文献
80.