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991.
Katsuyoshi Matsunami Hideaki Otsuka Kazunari Kondo Takakazu Shinzato Masatoshi Kawahata Kentaro Yamaguchi Yoshio Takeda 《Phytochemistry》2009,70(10):1277-1285
A lignan glucoside, (+)-pinoresinol 4-O-[6″-O-galloyl]-β-d-glucopyranoside (1), and two megastigmane glucosides, named macarangiosides E and F (2, 3), together with 15 known compounds (4–18) were isolated from leaves of Macaranga tanarius (L.) Müll.-Arg. (Euphorbiaceae). Their structures were elucidated by spectroscopic and chemical analyses. In addition, the absolute stereochemistry of macarangiosides B and C isolated previously from the same plant was also determined for the first time. Compounds 1 and 2 were galloylated on glucose and possessed potent DPPH radical-scavenging activity. 相似文献
992.
Toru Yago Yuki Nanke Naomi Ichikawa Tsuyoshi Kobashigawa Makio Mogi Naoyuki Kamatani Shigeru Kotake 《Journal of cellular biochemistry》2009,108(4):947-955
IL‐17 is a proinflammatory cytokine crucial for osteoclastic bone resorption in the presence of osteoblasts or synoviocytes in rheumatoid arthritis. However, the role of IL‐17 in osteoclastogenesis from human monocytes alone remains unclear. Here, we investigated the role of IL‐17 in osteoclastogenesis from human monocytes alone and the direct effect of infliximab on the osteoclastogenesis induced by IL‐17. Human peripheral blood mononuclear cells (PBMC) were cultured for 3 days with M‐CSF. After non‐adherent cells were removed, IL‐17 was added with either infliximab or osteoprotegerin (OPG). Seven days later, adherent cells were stained for vitronectin receptor. On the other hand, CD11b‐positive monocytes purified from PBMC were also cultured and stained as described above. CD11b‐positive cells were cultured with TNF‐α and receptor activator of NF‐κB ligand (RANKL). In the cultures of both adherent cells and CD11b‐positive cells, IL‐17 dose‐dependently induced osteoclastogenesis in the absence of soluble‐RANKL. OPG or infliximab inhibited IL‐17‐induced osteoclastogenesis. Interestingly, in the culture of CD11b‐positive cells, the osteoclastogenesis was more potently inhibited by infliximab than by OPG. TNF‐α and RANKL synergistically induced osteoclastogenesis. The present study clearly demonstrated the novel mechanism by which IL‐17 directly induces osteoclastogenesis from human monocytes alone. In addition, infliximab potently inhibits the osteoclastogenesis directly induced by IL‐17. J. Cell. Biochem. 108: 947–955, 2009. © 2009 Wiley‐Liss, Inc. 相似文献
993.
Osamu Nunobiki Masatsugu Ueda Michiko Yamamoto Eisaku Toji Naomi Sato Shinji Izuma Yoshiaki Okamoto Kiyo Torii Sadamu Noda 《Human cell》2009,22(4):101-106
Genetic polymorphisms of p53 and its negative regulator murine double minute 2 homolog (MDM2) have been shown to be closely associated with tumorigenesis in a variety of human cancers. In the present study, single nucleotide polymorphism (SNP) at p53 codon 72 and MDM2 promoter 309 was examined for germline DNA samples from 102 endometrial cancer cases and 95 controls using polymerase chain reaction-based fragment analysis. There were no significant differences in the genotype and allele prevalence between control subjects and endometrial cancer patients for p53 codon 72. The GG genotype frequency of MDM2-SNP309 was statistically higher in endometrial cancer patients than that in normal healthy women when compared with the TG genotype ( P = 0.0088). However, no statistically significant differences were found between the TT and TG or GG genotype frequencies and allele prevalence. Interestingly, the combination of the homozygous Arg/Arg genotype of p53 codon 72 and homozygous GG genotype of MDM2 SNP309 polymorphisms was significantly associated with the risk of endometrial cancer (odds ratio = 3.28, 95% confidence interval = 1.13 to 9.53, P = 0.0212). The homozygous variants of wild p53 codon 72 and mutant MDM2 promoter 309 may cooperatively increase the risk of endometrial cancer in a Japanese population. 相似文献
994.
Eduardo Gusmão Pereira Marco Antonio Oliva Kacilda Naomi Kuki José Cambraia 《Trees - Structure and Function》2009,23(2):277-285
The effect of iron solid particulate matter (SPMFe) deposited onto soil and leaves on photosynthesis and oxidative stress was evaluated in Clusia hilariana, a CAM tropical tree of high occurrence in Brazilian restingas. Significant increases in iron content were found in plants
exposed to SPMFe applied onto leaf and soil surfaces. However, only the application of SPMFe on leaves of C. hilariana caused significant reductions in some evaluated characteristics such as photosynthetic rate, stomatal conductance, transpiration,
organic acid accumulation, potential quantum yield of PSII, and changes in daily CAM photosynthesis pattern. Increase in relative
membrane permeability and reduction in catalase and superoxide dismutase activities in the leaves of plants exposed to SPMFe also were observed; however, lipid peroxidation did not change. These responses seem to be due to the combination of physical
effects such as increase of leaf temperature, reduction in light absorption, obstruction of stomatal pores, and biochemical
effects triggered by oxidative stress. 相似文献
995.
Kimi Araki Naoki Takeda Atsushi Yoshiki Yuichi Obata Naomi Nakagata Toshihiko Shiroishi Kazuo Moriwaki Ken-ichi Yamamura 《Mammalian genome》2009,20(1):14-20
MSM/Ms is an inbred mouse strain established from the Japanese wild mouse, Mus musculus molossinus, which has been phylogenetically distinct from common laboratory mouse strains for about 1 million years. The nucleotide
substitution rate between MSM/Ms and C57BL/6 is estimated to be 0.96%. MSM/Ms mice display unique characteristics not observed
in the commonly used laboratory strains, including an extremely low incidence of tumor development, high locomotor activity,
and resistance to high-fat-diet-induced diabetes. Thus, functional genomic analyses using MSM/Ms should provide a powerful
tool for the identification of novel phenotypes and gene functions. We report here the derivation of germline-competent embryonic
stem (ES) cell lines from MSM/Ms blastocysts, allowing genetic manipulation of the M. m. molossinus genome. Fifteen blastocysts were cultured in ES cell medium and three ES lines, Mol/MSM-1, -2, and -3, were established.
They were tested for germline competency by aggregation with ICR morulae and germline chimeras were obtained from all three
lines. We also injected Mol/MSM-1 ES cells into blastocysts of ICR or C57BL/6 × BDF1 mice and found that blastocyst injection
resulted in a higher production rate of chimeric mice than did aggregation. Furthermore, Mol/MSM-1 subclones electroporated
with a gene trap vector were also highly efficient at producing germline chimeras using C57BL/6 × BDF1 blastocyst injection.
This Mol/MSM-1 ES line should provide an excellent new tool allowing the genetic manipulation of the MSM/Ms genome. 相似文献
996.
997.
It is well known that most protein therapeutics such as monoclonal antibody pharmaceuticals and other biopharmaceuticals including cancer biomarkers are glycoproteins, and thus the development of high-throughput and sensitive analytical methods for glycans is essential in terms of their determination and quality control. We previously reported a novel alternative labeling method for glycans involving 9-fluorenylmethyl chloroformate (Fmoc-Cl) instead of the conventional reductive amination procedure. The derivatives were analyzed by high-performance liquid chromatography (HPLC) (Kamoda S, Nakano M, Ishikawa R, Suzuki S, Kakehi K. 2005. Rapid and sensitive screening of N-glycans as 9-fluorenylmethyl derivatives by high-performance liquid chromatography: A method which can recover free oligosaccharides after analysis. J Proteome Res. 4:146-152). This method was rapid and simple; however, it was time-consuming in terms of analysis by HPLC and did not provide so much information such as the detailed structures and mass numbers of glycans. Here we have developed a high-throughput and highly sensitive method. It comprises three steps, i.e., release of glycans, derivatization with Fmoc, and capillary electrophoresis-electrospray ionization mass spectrometry (CE-ESI MS) analysis. We analyzed several glycoproteins such as fetuin, alpha1 acid glycoprotein, IgG, and transferrin in order to validate this method. We were able to analyze the above glycoproteins with the three-step procedure within only 5 h, which provided detailed N-glycan patterns. Moreover, the MS/MS analysis allowed identification of the N-glycan structures. As novel applications, the method was employed for the analysis of N-glycans derived from monoclonal antibody pharmaceuticals and also from alpha-fetoprotein; the latter is known as one of the tumor markers of hepatocellular carcinomas. We were able to easily and rapidly determine the detailed structures of the N-glycans. The present method is very useful for the analysis of large numbers of samples such as a routine analysis. 相似文献
998.
Masaru Fujimoto Shin-ichiArimura Shoji Mano Maki Kondo Chieko Saito Takashi Ueda Mikio Nakazono Akihiko Nakano Mikio Nishimura Nobuhiro Tsutsumi 《The Plant journal : for cell and molecular biology》2009,58(3):388-400
Two similar Arabidopsis dynamin-related proteins, DRP3A and DRP3B, are thought to be key factors in both mitochondrial and peroxisomal fission. However, the functional and genetic relationships between DRP3A and DRP3B have not been fully investigated. In a yeast two-hybrid assay, DRP3A and DRP3B interacted with themselves and with each other. DRP3A and DRP3B localized to mitochondria and peroxisomes, and co-localized with each other in leaf epidermal cells. In two T-DNA insertion mutants, drp3a and drp3b , the mitochondria are a little longer and fewer in number than those in the wild-type cells. In the double mutant, drp3a/drp3b , mitochondria are connected to each other, resulting in massive elongation. Overexpression of either DRP3A or DRP3B in drp3a/drp3b restored the particle shape of mitochondria, suggesting that DRP3A and DRP3B are functionally redundant in mitochondrial fission. In the case of peroxisomal fission, DRP3A and DRP3B appear to have different functions: peroxisomes in drp3a were larger and fewer in number than those in the wild type, whereas peroxisomes in drp3b were as large and as numerous as those in the wild type, and peroxisomes in drp3a/drp3b were as large and as numerous as those in drp3a . Although overexpression of DRP3A in drp3a/drp3b restored the shape and number of peroxisomes, overexpression of DRP3B did not restore the phenotypes, and often caused elongation instead. These results suggest that DRP3B and DRP3A have redundant molecular functions in mitochondrial fission, whereas DRP3B has a minor role in peroxisomal fission that is distinct from that of DRP3A. 相似文献
999.
1000.