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71.
Compactin and simvastatin, but not pravastatin, induce bone morphogenetic protein-2 in human osteosarcoma cells 总被引:28,自引:0,他引:28
Sugiyama M Kodama T Konishi K Abe K Asami S Oikawa S 《Biochemical and biophysical research communications》2000,271(3):688-692
Bone morphogenetic protein (BMP)-2, a member of the BMP family, plays an important role in osteoblast differentiation and bone formation. To discover small molecules that induce BMP-2, a luciferase reporter vector containing the 5'-flanking promoter region of the human BMP-2 gene was constructed and transfected into human osteosarcoma (HOS) cells. By the screening of an in-house natural product library with stably transfected HOS cells, a fungal metabolite, compactin, known as an inhibitor of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, was isolated. The stimulation of the promoter activity by compactin seemed to be specific for BMP-2 gene in HOS cells, since it had little effect on BMP-4 or SV40 promoter activity and the stimulation was not observed in Chinese hamster ovary (CHO) cells. RT-PCR analysis and alkaline phosphatase assay revealed that compactin induced an increase in the expression of BMP-2 mRNA and protein. Like compactin, simvastatin also activated the BMP-2 promoter, whereas pravastatin did not. The statin-mediated activation of BMP-2 promoter was completely inhibited by the downstream metabolite of HMG-CoA reductase, mevalonate, indicating that the activation was a result of the inhibition of the enzyme. These results suggest that statins, if they are selectively targeted to bone, have beneficial effects in the treatment of osteoporosis or bone fracture. 相似文献
72.
Amplification of pepleomycin-mediated DNA cleavage and apoptosis by unfused aromatic cations 总被引:1,自引:0,他引:1
Kawanishi S Oikawa S Kawanishi M Sugiyama H Saito I Strekowski L Wilson WD 《Biochemistry》2000,39(43):13210-13215
An important approach to improve chemotherapy of members of the bleomycin (BLM) family of antibiotics is to find compounds (amplifiers) that enhance the activity of BLM-mediated DNA cleavage and apoptosis. Using a DNA-sequencing technique and pulsed field gel electrophoresis, we have investigated whether BLM-mediated cleavage of isolated and cellular DNA is amplifed by three compounds (RW-12, LS-20, 1S-5Me) which have a conformationally flexible, unfused polyaromatic system and cationic side chain in the molecules. RW-12 enhanced most effectively both pepleomycin (PEM)-induced cytotoxicity and apoptosis. The order of the maximum enhancing effect of amplifiers on PEM-mediated DNA damage is RW-12 > LS-20 > 1S-5Me. RW-12 amplified PEM-mediated DNA cleavage most effectively not only in vitro but also in cultured cells. We have reported that the order of the DNA binding constants of these compounds is RW-12 > LS-20 > 1S-5Me. In this study, we found a good correlation between PEM-mediated cleavage of isolated DNA and cellular DNA. These results suggest that BLM amplifiers bind to DNA and by doing so enhance drug-mediated DNA degradation, ultimately leading to apoptosis. The present study on amplifiers of anticancer agents shows a novel approach to the potentially effective anticancer therapy. 相似文献
73.
An efficient system for clonal mass propagation in liquid culture was established for the propagation of ornamental gentian.
In a test of the requirements for three cytokinins [6-benzylaminopurine, N-(2-chloro-4-pyridyl)-N′-phenylurea and N-phenyl-N′-1,2,3-thiadiazol-5-yl urea (TDZ)] in combination with 1-naphthaleneacetic acid (NAA), we found that effective propagation
of shoots occurred with 0.01 mg l–1 TDZ in a 300 ml conical flask that contained 100 ml of medium. The propagation of shoots was also affected by the concentrations
of macronutrients (KNO3, NH4NO3 and CaCl2) and sucrose in Murashige and Skoog's (MS) medium, and it was influenced to some extent by the speed of agitation on an orbital
shaker. The most efficient propagation of shoots was achieved in full-strength MS medium supplemented with 0.01 mg l–1 TDZ and 20 g l–1 sucrose with agitation at 150 rpm. The propagation of shoots was maximal after 6 weeks of culture (140 shoots from five nodal
segments in one flask). Large-scale propagation in a 5-l fermenter was attempted using 3 l of MS medium that contained 0.01
mg l–1 TDZ and 20 g l–1 sucrose. More than 2,000 shoots were obtained in the fermenter in 5 weeks following the initial cultivation of five nodal
segments for 6 weeks in one 300-ml flask. The shoots that had propagated in the fermenter were transferred directly to soil
without prior rooting in vitro and were easily acclimatized within 1 month.
Received: 7 October 1997 / Revision received: 16 January 1998 / Accepted: 30 January 1998 相似文献
74.
Quantitative proteomics of Arabidopsis shoot microsomal proteins reveals a cross‐talk between excess zinc and iron deficiency
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Sajad Majeed Zargar Rie Kurata Shoko Inaba Akira Oikawa Risa Fukui Yoshiyuki Ogata Ganesh Kumar Agrawal Randeep Rakwal Yoichiro Fukao 《Proteomics》2015,15(7):1196-1201
Iron (Fe) deficiency significantly effects plant growth and development. Plant symptoms under excess zinc (Zn) resemble symptoms of Fe‐deficient plants. To understand cross‐talk between excess Zn and Fe deficiency, we investigated physiological parameters of Arabidopsis plants and applied iTRAQ‐OFFGEL quantitative proteomic approach to examine protein expression changes in microsomal fraction from Arabidopsis shoots under those physiological conditions. Arabidopsis plants manifested shoot inhibition and chlorosis symptoms when grown on Fe‐deficient media compared to basal MGRL solid medium. iTRAQ‐OFFGEL approach identified 909 differentially expressed proteins common to all three biological replicates; the majority were transporters or proteins involved in photosynthesis, and ribosomal proteins. Interestingly, protein expression changes between excess Zn and Fe deficiency showed similar pattern. Further, the changes due to excess Zn were dramatically restored by the addition of Fe. To obtain biological insight into Zn and Fe cross‐talk, we focused on transporters, where STP4 and STP13 sugar transporters were predominantly expressed and responsive to Fe‐deficient conditions. Plants grown on Fe‐deficient conditions showed significantly increased level of sugars. These results suggest that Fe deficiency might lead to the disruption of sugar synthesis and utilization. 相似文献
75.
Maiko Matsushita Yoshie Ozaki Yuka Hasegawa Fukiko Terada Noriko Tabata Hirokazu Shiheido Hiroshi Yanagawa Tsukasa Oikawa Koichi Matsuo Wenlin Du Taketo Yamada Masashi Hozumi Daiju Ichikawa Yutaka Hattori 《PloS one》2015,10(1)
Despite the recent advances in the treatment of multiple myeloma (MM), MM patients with high-risk cytogenetic changes such as t(4;14) translocation or deletion of chromosome 17 still have extremely poor prognoses. With the goal of helping these high-risk MM patients, we previously developed a novel phthalimide derivative, TC11. Here we report the further characterization of TC11 including anti-myeloma effects in vitro and in vivo, a pharmacokinetic study in mice, and anti-osteoclastogenic activity. Intraperitoneal injections of TC11 significantly delayed the growth of subcutaneous tumors in human myeloma-bearing SCID mice. Immunohistochemical analyses showed that TC11 induced apoptosis of MM cells in vivo. In the pharmacokinetic analyses, the Cmax was 2.1 μM at 1 h after the injection of TC11, with 1.2 h as the half-life. TC11 significantly inhibited the differentiation and function of tartrate-resistant acid phosphatase (TRAP)-positive multinucleated osteoclasts in mouse osteoclast cultures using M-CSF and RANKL. We also revealed that TC11 induced the apoptosis of myeloma cells accompanied by α-tubulin fragmentation. In addition, TC11 and lenalidomide, another phthalimide derivative, directly bound to nucleophosmin 1 (NPM1), whose role in MM is unknown. Thus, through multiple molecular interactions, TC11 is a potentially effective drug for high-risk MM patients with bone lesions. The present results suggest the possibility of the further development of novel thalidomide derivatives by drug designing. 相似文献
76.
Masaharu Tsubokura Shigeaki Kato Tomohiro Morita Shuhei Nomura Masahiro Kami Kikugoro Sakaihara Tatsuo Hanai Tomoyoshi Oikawa Yukio Kanazawa 《PloS one》2015,10(6)
An assessment of the external and internal radiation exposure levels, which includes calculation of effective doses from chronic radiation exposure and assessment of long-term radiation-related health risks, has become mandatory for residents living near the nuclear power plant in Fukushima, Japan. Data for all primary and secondary children in Minamisoma who participated in both external and internal screening programs were employed to assess the annual additional effective dose acquired due to the Fukushima Daiichi nuclear power plant disaster. In total, 881 children took part in both internal and external radiation exposure screening programs between 1st April 2012 to 31st March 2013. The level of additional effective doses ranged from 0.025 to 3.49 mSv/year with the median of 0.70 mSv/year. While 99.7% of the children (n = 878) were not detected with internal contamination, 90.3% of the additional effective doses was the result of external radiation exposure. This finding is relatively consistent with the doses estimated by the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR). The present study showed that the level of annual additional effective doses among children in Minamisoma has been low, even after the inter-individual differences were taken into account. The dose from internal radiation exposure was negligible presumably due to the success of contaminated food control. 相似文献
77.
Functionality of insect‐cell‐derived colorectal cancer vaccine candidate protein EpCAM‐Fc in human dendritic cells
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Yo Seph Park Jeong‐Hwan Lee Jin‐Yeon Park Han Sung Hwang Martin Zenke Dong Wook Han Young Sun Kang Kisung Ko Kinarm Ko 《Entomological Research》2015,45(3):162-166
The baculovirus–insect cell expression system is widely used to produce recombinant proteins for various biomedical applications. Our previous study demonstrated that EpCAM, a colorectal cancer vaccine candidate protein, can be expressed in the baculovirus–insect cell expression system. However, its functionality (the ability to elicit an immune response), which is important for its possible use as a colorectal cancer vaccine for immunotherapy, still needed to be confirmed. In this study, we examined the ability of recombinant EpCAM to induce maturation of immature dendritic cells (DCs) derived from CD34+ cells isolated from human umbilical cord blood. We demonstrated that EpCAM induces the expression of four DC maturation markers: CD80, CD83, CD86 and MHC II. These results suggest that EpCAM produced in the baculovirus–insect cell expression system is functional in terms of its ability to trigger maturation of human DCs. 相似文献
78.
Patricia Y. Oikawa G. Darrel Jenerette David A. Grantz 《Global Change Biology Bioenergy》2015,7(5):974-983
High irradiance arid environments are promising, yet understudied, areas for biofuel production. We investigated the productivity and environmental trade‐offs of growing sorghum (Sorghum bicolor) as a biofuel feedstock in the low deserts of California (CA). Using a 5.3 ha experimental field in the Imperial Valley, CA, we measured aboveground biomass production and net ecosystem exchange of CO2 and H2O via eddy covariance over three growing periods between February and November 2012. Environmental conditions were extreme, with high irradiance, vapor pressure deficit (VPD), and air temperature throughout the growing season. Air temperature peaked in August with a maximum of 45.7 °C. Sorghum produced an annual aboveground biomass yield of 43.7 Mg per hectare. Net ecosystem exchange (NEE) was highest during the summer growth period and reached a maximum of ?68 μmol CO2 m?2 s?1. Water use efficiency, or biomass water ratio (BWR), was high (4.0 g dry biomass kg?1 H2O) despite high seasonal evapotranspiration (1094 kg H2O m?2). The BWR of sorghum surpassed that of many C4 biofuel candidate crops in the United States, as well as that of alfalfa which is currently widely grown in the Imperial Valley. Sorghum also outperformed many US biofuel crops in terms of radiation use efficiency (RUE), achieving 1.5 g dry biomass MJ?1. We found no evidence of saturation of NEE at high levels of photosynthetically active radiation (PAR) (up to 2250 μmol m?2 s?1). In addition, we found no evidence that NEE was inhibited by either high VPD or air temperature during peak photosynthetic phases. The combination of high productivity, high BWR, and high RUE suggests that sorghum is well adapted to this extreme environment. The biomass production rates and efficiency metrics spanning three growing periods provide fundamental data for future Life Cycle Assessments (LCA), which are needed to assess the sustainability of this sorghum biofuel feedstock system. 相似文献
79.
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