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201.
Takashi Matsumoto Keiko Okunishi Koh Nishida Masao Noguchi 《Bioscience, biotechnology, and biochemistry》2013,77(2):485-490
In order to obtain a basic information of plant cell suspension culture as a step toward the development of large scale culture, culture conditions of crown gall cells (auxin non-requiring cells) were investigated. Addition of yeast extract to culture medium was significantly effective for the growth and cell dispersion.In experiments on the ability of the cultured cells to utilize sugars as the carbon source, it was observed that galactose, added to the culture medium, markedly inhibited the cell growth.Pasteurization of the medium containing fructose as carbon source made it brownish by Maillard reaction and the medium apparently restrained the cell growth. However, the fructose medium sterilized by filtration was excellent for the cell growth as well as sucrose or glucose medium. In a jar fermentor, even the glucose medium became brownish by heat sterilization and the brown colored medium restrained the cell growth. Under optimum conditions, the doubling time was 1.1 day in exponential phase and 2.0 g of cell (dry weight) per 100 ml culture was obtained as the maximum yield. 相似文献
202.
Collier N Doan S Kawazoe A Goodwin RM Conway M Tateno Y Ngo QH Dien D Kawtrakul A Takeuchi K Shigematsu M Taniguchi K 《Bioinformatics (Oxford, England)》2008,24(24):2940-2941
SUMMARY: BioCaster is an ontology-based text mining system for detecting and tracking the distribution of infectious disease outbreaks from linguistic signals on the Web. The system continuously analyzes documents reported from over 1700 RSS feeds, classifies them for topical relevance and plots them onto a Google map using geocoded information. The background knowledge for bridging the gap between Layman's terms and formal-coding systems is contained in the freely available BioCaster ontology which includes information in eight languages focused on the epidemiological role of pathogens as well as geographical locations with their latitudes/longitudes. The system consists of four main stages: topic classification, named entity recognition (NER), disease/location detection and event recognition. Higher order event analysis is used to detect more precisely specified warning signals that can then be notified to registered users via email alerts. Evaluation of the system for topic recognition and entity identification is conducted on a gold standard corpus of annotated news articles. AVAILABILITY: The BioCaster map and ontology are freely available via a web portal at http://www.biocaster.org. 相似文献
203.
Advanced glycation end products-induced apoptosis and overexpression of vascular endothelial growth factor in bovine retinal pericytes. 总被引:14,自引:0,他引:14
Sho-ichi Yamagishi Shinjiro Amano Yosuke Inagaki Tamami Okamoto Kohachiro Koga Nobuyuki Sasaki Hiroshi Yamamoto Masayoshi Takeuchi Zenji Makita 《Biochemical and biophysical research communications》2002,290(3):973-978
The influence of advanced glycation end products (AGEs) on apoptotic cell death and vascular endothelial growth factor (VEGF) gene expression in cultured bovine retinal pericytes was investigated. When pericytes were incubated with three immunochemically distinct AGEs, which were prepared in vitro by incubating bovine serum albumin with glucose, glyceraldehyde, or glycolaldehyde, apoptotic cell death and DNA ladder formation were significantly induced. The cytopathic effects of glyceraldehyde- or glycolaldehyde-derived AGEs were significantly enhanced in AGE receptor-transfected pericytes. Furthermore, all of these AGEs were found to upregulate the secretory forms of VEGF mRNA levels in retinal pericytes. These results suggest that AGEs disturbed retinal microvascular homeostasis by inducing pericyte apoptosis and VEGF overproduction and thus were involved in the pathogenesis of early phase diabetic retinopathy. 相似文献
204.
The dopamine D2 receptor (D2R) is target for antipsychotic drugs and associated with several neuropsychiatric disorders. D2R has a long third cytoplasmic loop and a short carboxyl-terminal cytoplasmic tail. It exists as two alternatively spliced isoforms, termed D2LR and D2SR, which differ in the presence and absence, respectively, of a 29 amino acid insert in the third cytoplasmic loop. To evaluate the differential roles of the two D2R isoforms, we transfected both isoforms into NG108-15 cells and observed their subcellular localization by a confocal laser scanning light microscope. D2SR was predominantly localized at the plasma membrane, whereas D2LR was mostly retained in the perinuclear region around the Golgi apparatus. Using a yeast two hybrid system with a mouse brain cDNA library and coimmunoprecipitation assay, we found that heart-type fatty acid binding protein (H-FABP) interacts with D2LR but not with D2SR. H-FABP is a cytosolic protein involved in binding and transport of fatty acids. Overexpressed H-FABP and endogenous H-FABP were colocalized with the intracellular D2LR in NG108-15 cells. Furthermore, in the rat striatum, H-FABP was detected in the D2R-expressing neurons. From these results, H-FABP is associated with D2LR, and may thereby modulate the subcellular localization and function of D2LR. 相似文献
205.
Lipopolysaccharide activates matrix metalloproteinase-2 in endothelial cells through an NF-kappaB-dependent pathway 总被引:11,自引:0,他引:11
Vascular endothelial cells release proteinases that degrade the extracellular matrix, thus enabling cell migration during angiogenesis and vasculogenesis. Endothelial cells secrete mainly the proform of matrix metalloproteinase-2 (proMMP-2). In this report, we examined several growth factors, cytokines, and other molecules for activation of MMP-2 by human umbilical vein endothelial cells. Of these factors, we found that lipopolysaccharide (LPS) is the strongest activator of MMP-2. LPS induced MMP-2 activation in a time- and dose-dependent manner. While pretreatment with zinc chelators or nuclear factor kappaB (NF-kappaB) inhibitors suppressed LPS-induced MMP-2 activation, pretreatment with phosphatidylinositol 3'-kinase inhibitors had no effect. These results indicate that, in endothelial cells, LPS can directly enhance angiogenesis by inducing MMP-2 activation mediated through an NF-kappaB pathway. 相似文献
206.
Three Japanese families with members carrying C7 silent allele (C7*Q0). Possibility for an association between C7*Q0 and C6*B 总被引:1,自引:0,他引:1
Three Japanese families with members carrying C7 silent allele(s) (C7*Q0) are presented. C6 types in the family members were also examined, and it was found that C7*Q0 was transmitted from a parent to offsprings as a haplotype, C7*Q0-C6*B. In another study of C6 types in sera from 3 volunteer blood donors with homozygous C7 deficiencies, the C6 phenotypes were found to be C6 B (homozygote). It seems remarkable that C7*Q0 can be associated with C6*B. 相似文献
207.
208.
Atsushi Okazawa Chitra Trakulnaleamsai Hiroya Hiramatsu Ei'ichiro Fukusaki Koichi Yoneyama Yasutomo Takeuchi Akio Kobayashi 《Plant Physiology and Biochemistry》2005,43(5):499-502
Orobanche minor is a non-photosynthetic root holoparasitic plant. Although it is known that photosynthesis-related genes are inactivated or have been eliminated from the plastid genomes of holoparasites, little is known about the alterations in their genes involved in the signaling networks by which light regulates photosynthesis. Cryptochromes (crys), which are blue-light receptors, appear to control both photosynthesis-related and non-photosynthetic responses to light in higher plants. Because we are interested in to what extent a cry-mediated light signaling network remains in the holoparasites, we cloned CRY homologous cDNA from O. minor (OmCRY1) and used real-time RT-PCR to compare its expression under natural daylight and darkness. We found that the OmCRY1 has a high degree of homology with CRY1 s from photosynthetic plants. Expression of the OmCRY1 gene was higher in plants grown in the dark than that in the plants grown under natural daylight. This is the first report of the gene expression of a blue-light receptor in non-photosynthetic plants. 相似文献
209.
Flesh‐eating Streptococcus pyogenes triggers the expression of receptor activator of nuclear factor‐κB ligand 下载免费PDF全文
Hidenori Matsui Yuriko Nakatani Haruno Yoshida Asako Takizawa Osamu Takeuchi Anders Øverby Takashi Takahashi Somay Y. Murayama Koichi Matsuo 《Cellular microbiology》2016,18(10):1390-1404
Human CD46 is a receptor for the M protein of group A streptococcus (GAS). The emm1 GAS strain GAS472 was isolated from a patient suffering from streptococcal toxic shock‐like syndrome. Human CD46‐expressing transgenic (Tg) mice developed necrotizing fasciitis associated with osteoclast‐mediated progressive and severe bone destruction in the hind paws 3 days after subcutaneous infection with 5 × 105 colony‐forming units of GAS472. GAS472 infection induced expression of the receptor activator of nuclear factor‐κB ligand (RANKL) while concomitantly reducing osteoprotegerin expression in the hind limb bones of CD46 Tg mice. Micro‐computed tomography analysis of the bones suggested that GAS472 infection induced local bone erosion and systemic bone loss in CD46 Tg mice. Because treatment with monoclonal antibodies (mAbs) against mouse CD4+ and CD8+ T lymphocytes did not inhibit osteoclastogenesis, T lymphocyte‐derived RANKL was not considered a major contributor to massive bone loss during GAS472 infection. However, immunohistochemical analysis of the hind limb bones showed that GAS472 infection stimulated RANKL production in various bone marrow cells, including fibroblast‐like cells. Treatment with a mAb against mouse RANKL significantly inhibited osteoclast formation and bone resorption. These data suggest that increased expression of RANKL in heterogeneous bone marrow cells provoked bone destruction during GAS infection. 相似文献
210.
Toshio Watanabe Toshihisa Takeuchi Osamu Handa Yasuhisa Sakata Tetsuya Tanigawa Masatsugu Shiba Yuji Naito Kazuhide Higuchi Kazuma Fujimoto Toshikazu Yoshikawa Tetsuo Arakawa 《PloS one》2015,10(4)