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51.
Hiroshi Fukui Hiroshi Egawa Koichi Koshimizu Tetsuo Mitsui 《Bioscience, biotechnology, and biochemistry》2013,77(2):417-421
A new isoflavone having antifungal activity was isolated from immature fruits of Lupinus luteus (Leguminosae), and named luteone. The structure was shown to be 5,7,2′,4′-tetrahy-droxy-6-(3,3-dimethylallyl)-isoflavone by degradative and spectroscopic studies. 相似文献
52.
Atsumi Kamogawa Kozi Yokobayashi Toshio Fukui 《Bioscience, biotechnology, and biochemistry》2013,77(12):2813-2819
Maltose phosphorylase (EC 2.4.1.8) from Lactobacillus brevis was purified 29-fold over the crude extract. The final preparation was at least 80% pure and had a specific activity of 18 units/mg protein. The molecular weights of the native enzyme and of the component dissociated in sodium dodecyl sulfate were 150,000 and 80,000, respectively. The enzyme does not contain pyridoxal-5′-phosphate as a cofactor. It can not act on maltitol, malto-triitol, sucrose, lactose and trehalose, and essentially not on isomaltose, maltobionic acid, maltotriose and maltotetraose. Inhibitory effect was observed with CuSO4, HgCl2 and p-chloromercuribenzoate. Some other properties were also examined. A possibility of using this enzyme for the analysis of maltose was proposed. 相似文献
53.
Takao Takahashi Noriko Yamada Kiichi Iwamoto Yoshihide Shimabayashi Kosaku Izutsu 《Bioscience, biotechnology, and biochemistry》2013,77(1):29-36
The phytohemagglutinin of rice seed has been purified by a sequence of steps involving fractionation with ammonium sulfate and successive chromatography on DEAE-and eMcellulose and finally gel filtration on Bio-Gel P-100. The purified rice seed hemagglutinin was shown to be homogeneous by electrophoresis on polyacrylamide gel and its molecular weight was 10,000, calculated from both the Ve/Vo value of gel filtration on Bio-Gel P-100 and the sum of the individual constituents (amino acids, sugars and metals). In addition to amino acid, the rice seed hemagglutinin contained 26.8% covalently bound carbohydrate which was identified and quantitated by gas chromatography of the acetylated alditols. Glucose was the predominant sugar with lesser amounts of glucosamine, xylose, and mannose also being present. And the rice seed hemagglutinin contained 1 g atom of calcium per molecule. The molecular weight of the rice seed hemagglutinin is smallest compared with some of phytohemagglutinins isolated from leguminous seeds and other plant sources. The rice seed hemagglutinin has the blastogenetic activity for human peripheral lymphocytes as well as Phaseolus vulgaris phytohemagglutinins or concanavalin A, jack bean hemagglutinin. 相似文献
54.
Sakuzo Fukui 《Bioscience, biotechnology, and biochemistry》2013,77(2):321-324
The relation between the rate of increase in nonprotein nitrogenous compounds (NPN) of rabbit muscle and muscle pH ranging from 5.9 to 7.2 was examined during the post-mortem storage. Muscle of a high ultimate pH was prepared by the injection of ICH2COOH into the vein. The more the muscle pH kept away from 6.3, the more NPN increased. Therefore, it has been suggested that the post-mortem proteolysis is mainly attributed to the acid proteolytic system comprising cathepsins in muscles at a pH lower than 6.3 and to the neutral proteolytic system in muscles at a pH higher than 6.3.The ratio of the increment of ninhydrin positive materials to that of Cu-Folin phenol reagent positive materials among NPN was relatively large in muscles at a high pH. This result has suggested that the neutral proteolytic system was more abound in exopeptidase activity than acid proteolytic system. 相似文献
55.
Lin Feng Hao Wu Lingling E Dongsheng Wang Fukui Feng Yuwan Dong Hongchen Liu Lili Wang 《PloS one》2013,8(12)
To study the relationship between vascular endothelial growth factor (VEGF) and formation and repair of engineering bone, second-generation bone marrow stromal cells (BMSCs) of New Zealand white rabbits that were separated in vitro were transfected with VEGF 165 gene vectors by adenovirus to detect gene expressions. Transfected BMSCs and β-tricalcium phosphate material were complexed and implanted at the femoral injury sites of the study group (n = 12), and the control group (n = 12) were implanted with engineering bones that were not transfected with VEGF. Femoral recoveries of the two groups were observed on the 15th, 30th, 45th and 60th days, and their vascularization and ossification statuses were observed by immunohistochemical methods. The BMSCs transfected with VEGF highly expressed VEGF genes and excreted VEGF. The two groups both experienced increased vascularization and bone volume after implantation (t = 7.92, P<0.05), and the increases of the study group were significantly higher than those of the control group (t = 6.92, P<0.05). VEGF is clinically applicable because it can accelerate the formation and repair of engineering bone by promoting vascularization and ossification. 相似文献
56.
Nobuho Tanaka Yasuko Ikeda Tetsuo Yamaguchi Hiroshi Furukawa Hiroyuki Mitomi Takumi Nakagawa Shigeto Tohma Naoshi Fukui 《Arthritis research & therapy》2013,15(5):R127
Introduction
Articular chondrocytes undergo an obvious phenotypic change when cultured in monolayers. During this change, or dedifferentiation, the expression of type I and type III procollagen is induced where normal chondrocytes express little type I and type III procollagen. In this study, we attempted to determine the mechanism(s) for the induction of such procollagen expression in dedifferentiating chondrocytes.Methods
All experiments were performed using primary-cultured human articular chondrocytes under approval of institutional review boards. Integrin(s) responsible for the induction of type I and type III procollagen expression were specified by RNAi experiments. The signal pathway(s) involved in the induction were determined by specific inhibitors and RNAi experiments. Adenovirus-mediated experiments were performed to identify a small GTPase regulating the activity of integrins in dedifferentiating chondrocytes. The effect of inhibition of integrins on dedifferentiation was investigated by experiments using echistatin, a potent disintegrin. The effect of echistatin was investigated first with monolayer-cultured chondrocytes, and then with pellet-cultured chondrocytes.Results
In dedifferentiating chondrocytes, α5β1 integrin was found to be involved in the induction of type I and type III procollagen expression. The induction was known to be mediated by v-akt murine thymoma viral oncogene homolog (AKT) signaling. Among the three AKT isoforms, AKT1 seemed to be most involved in the signaling. Elated RAS viral (r-ras) oncogene homolog (RRAS) was considered to regulate the progression of dedifferentiation by modulating the affinity and avidity of α5β1 integrin to ligands. Echistatin inhibited dedifferentiation of monolayer-cultured chondrocytes. Furthermore, the matrix formed by pellet-cultured chondrocytes more closely resembled that of normal cartilage compared with the controls.Conclusions
The result of this study has shown, for the first time, that α5β1 integrin may be responsible for the induction of non-cartilaginous collagen expression in chondrocytes undergoing dedifferentiation. Again, this study has shown that the inhibition of ligand ligation to integrins may be an effective strategy to inhibit phenotypic change of cultured chondrocytes, and to improve the quality of matrix synthesized by primary cultured chondrocytes. 相似文献57.
Dai Fukui Kishio Maeda David A. Hill Sumiko Matsumura Naoki Agetsuma 《Acta theriologica》2005,50(3):309-322
The distribution ofMurina silvatica (Yoshiyuki, 1983) in the Japanese archipelago extends over about 2000 km from north to south. Specimens were obtained from
populations in Hokkaido and Yakushima, which are at the northern and southern ends of the range, and from two intermediate
locations in Honshu. Measurements of cranial and external morphology were examined for evidence of geographical variation.
The results of both multivariate analysis of variance and cluster analysis showed that there was no distinct cline in skull
morphology among the Hokkaido, Tohoku and Chubu populations. However, the results of multivariate analysis of variance showed
that all measures were significantly greater for the Yakushima population than for the others. Similarly, in a dendrogram
of cluster analysis, the Yakushima population formed a cluster that was distinct from the other populations. However, as the
difference between the Yakushima population and the other populations was less than the variation found within the Hokkaido,
Tohoku and Chubu populations, morphological divergence of the Yakushima population was attributable to intraspecific variation.
The island of Yakushima is the most isolated of the four locations and the morphological divergence of this population may
be associated with its relative geographic isolation. 相似文献
58.
Akihiko Nishikimi Mutsuko Kukimoto-Niino Shigeyuki Yokoyama Yoshinori Fukui 《Experimental cell research》2013
DOCK proteins constitute a family of evolutionarily conserved guanine nucleotide exchange factors (GEFs) for Rho family of GTPases. Although DOCK family proteins do not contain the Dbl homology domain typically found in GEFs, they mediate the GTP–GDP exchange reaction through DHR-2 domain. Accumulating evidence indicates that the DOCK proteins act as major GEFs in varied biological settings. For example, DOCK2, which is predominantly expressed in hematopoietic cells, regulates migration and activation of leukocytes through Rac activation. On the other hand, it was recently reported that mutations of DOCK8, another member of the DOCK family proteins, cause a combined immunodeficiency syndrome in humans. This article reviews the structure, functions and signaling of DOCK2 and DOCK8, especially focusing on their roles in immune responses. 相似文献
59.
Tomohiro Watanabe Hisaya Kojima Yoshinori Takano Manabu Fukui 《Systematic and applied microbiology》2013
The diversity of sulfate-reducing prokaryotes (SRPs) and sulfur-oxidizing prokaryotes (SOPs) in freshwater lake ecosystems was investigated by cloning and sequencing of the aprA gene, which encodes for a key enzyme in dissimilatory sulfate reduction and sulfur oxidation. To understand their diversity better, the spatial distribution of aprA genes was investigated in sediments collected from six geographically distant lakes in Antarctica and Japan, including a hypersaline lake for comparison. The microbial community compositions of freshwater sediments and a hypersaline sediment showed notable differences. The clones affiliated with Desulfobacteraceae and Desulfobulbaceae were frequently detected in all freshwater lake sediments. The SOP community was mainly composed of four major phylogenetic groups. One of them formed a monophyletic cluster with a sulfur-oxidizing betaproteobacterium, Sulfuricella denitrificans, but the others were not assigned to specific genera. In addition, the AprA sequences, which were not clearly affiliated to either SRP or SOP lineages, dominated the libraries from four freshwater lake sediments. The results showed the wide distribution of some sulfur-cycle prokaryotes across geographical distances and supported the idea that metabolic flexibility is an important feature for SRP survival in low-sulfate environments. 相似文献
60.