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71.
Ko-ichiro Miyamoto Parida Yamada Ryo-taro Yamaguchi Takami Muto Ayumi Hirano Yasuo Kimura Michio Niwano Hiroko Isoda 《Cytotechnology》2007,55(2-3):143-149
In this study, we report on an in situ monitoring system of living cultured cells using infrared absorption spectroscopy in
the geometry of multiple internal reflections (MIR-IRAS). In order to observe living cultured cells, the temperature in the
sample chamber of a FT-IR spectrometer was maintained at 37 °C and a humidified gas mixture containing 5% CO2 was introduced into the sample chamber. Human breast cell line MCF-7 cultured on Si MIR prisms were placed in the sample
chamber and infrared spectra of MCF-7 cells were collected for 5 h. It was found that the adhesion and metabolism of MCF-7
cells could be monitored by the absorption intensity of amide-II protein band (1,545 cm−1) and also by the absorption intensities of CH
x
bands (2,700–3,100 cm−1). These results suggest that our system is useful for a nondestructive and non-label monitoring of cell viability. Our method
based on infrared absorption spectroscopy has a potential for bioscreening application. 相似文献
72.
An envelope-shaped film culture vessel (named Culture Bag) made of fluorocarbon polymer film, which is much more permeable to oxygen, nitrogen and carbon dioxide than other films, was found to be suitable to grow plant cells in liquid medium without agitation. Proliferous BY-2 tobacco cells showed almost the same growth in a Culture Bag of 12.5 m-thick film as that in a shake flask; the growth was lower in a Culture Bag of a thicker film. Lithospermum erythrorhizon cells produced almost the same amount of red naphthoquinone pigments (shikonin derivatives) in a Culture Bag of 12.5 m-thick film as those in a shake flask although the productivity was suppressed as the film thickness increased. L. erythrorhizon cells in a Culture Bag produced much less abnormal stress metabolites (orange-colored benzoquinone derivatives) than those in a shake flask, suggesting that culturing cells in the Culture Bag was less stressful due to its stationary liquid environment. 相似文献
73.
The structure of nucleosome core particles as revealed by difference Raman spectroscopy. 总被引:1,自引:0,他引:1 下载免费PDF全文
Raman spectra have been observed of nucleosome core particles (I) prepared from chicken erythrocyte chromatin, its isolated 146 bp DNA (II), and its isolated histone octamer (H2A+H2B+H3+H4)2 (III). By examining the difference Raman spectra, (I)-(II), (I)-(III), and (I)-(II)-(III), several pieces of information have been obtained on the conformation of the DNA moiety, the conformation of the histone moiety, and the DNA-histone interaction in the nucleosome core particles. In the nucleosome core particles, about 15 bp (A.T rich) portions of the whole 146 bp DNA are considered to take an A-form conformation. These are considered to correspond to its bent portions which appear at intervals of 10 bp. 相似文献
74.
In a chromosome study on leucocyte cultures made in 13 patients treated with chlorpromazine, 15 treated with perphenazine, and nine treated with lysergide, a significantly higher frequency of gaps, breaks, and hypodiploid cells in the patients treated with perphenazine and lysergide occurred compared with the 41 controls studied. It is concluded that if some drugs can induce major chromosome abnormalities, and less toxic alternatives are available, the latter should be used in preference. 相似文献
75.
76.
Furuta T Murao LA Lan NT Huy NT Huong VT Thuy TT Tham VD Nga CT Ha TT Ohmoto Y Kikuchi M Morita K Yasunami M Hirayama K Watanabe N 《PLoS neglected tropical diseases》2012,6(2):e1505
Background
Recent in-vitro studies have suggested that mast cells are involved in Dengue virus infection. To clarify the role of mast cells in the development of clinical Dengue fever, we compared the plasma levels of several mast cell-derived mediators (vascular endothelial cell growth factor [VEGF], soluble VEGF receptors [sVEGFRs], tryptase, and chymase) and -related cytokines (IL-4, -9, and -17) between patients with differing severity of Dengue fever and healthy controls.Methodology/Principal Findings
The study was performed at Children''s Hospital No. 2, Ho Chi Minh City, and Vinh Long Province Hospital, Vietnam from 2002 to 2005. Study patients included 103 with Dengue fever (DF), Dengue hemorrhagic fever (DHF), and Dengue shock syndrome (DSS), as diagnosed by the World Health Organization criteria. There were 189 healthy subjects, and 19 febrile illness patients of the same Kinh ethnicity. The levels of mast cell-derived mediators and -related cytokines in plasma were measured by ELISA. VEGF and sVEGFR-1 levels were significantly increased in DHF and DSS compared with those of DF and controls, whereas sVEGFR-2 levels were significantly decreased in DHF and DSS. Significant increases in tryptase and chymase levels, which were accompanied by high IL-9 and -17 concentrations, were detected in DHF and DSS patients. By day 4 of admission, VEGF, sVEGFRs, and proteases levels had returned to similar levels as DF and controls. In-vitro VEGF production by mast cells was examined in KU812 and HMC-1 cells, and was found to be highest when the cells were inoculated with Dengue virus and human Dengue virus-immune serum in the presence of IL-9.Conclusions
As mast cells are an important source of VEGF, tryptase, and chymase, our findings suggest that mast cell activation and mast cell-derived mediators participate in the development of DHF. The two proteases, particularly chymase, might serve as good predictive markers of Dengue disease severity. 相似文献77.
Takehiko Fukushima Kazuo Matsushige Noriko Takamura Michio Fukushima 《Hydrobiologia》2004,511(1-3):201-213
Quasi-continuous DO and pH measurements (total 47 days) were conducted during enclosure experiments (6 enclosures; 5 × 5 × 2.5 m), in which a biomass gradient of silver carp was created. After subtracting the air–water exchanges of O2 and CO2, the chemical and biochemical changes in DO (dissolved oxygen) and DIC (dissolved inorganic carbon) were estimated in order to evaluate MQ (metabolic quotient: DO change divided by DIC change) at intervals of 1 hour. By removing small absolute changes below the threshold value (0.01 mM h?1), the averaged values of the 24 MQ means for the respective 1-hour periods ranged from 0.96 to 1.20 in the six enclosures. Because the MQs in the daytime inversely correlated well with the ratio of NH+ 4–N to (NH+ 4–N + NO? 3–N), not the ecosystems, i.e., density of fish, community structure of zooplankton and phytoplankton, but the form of nitrogen uptaken for primary production principally determined the MQs. The higher MQs observed in the daytime compared with the nighttime (from 14% to 21% except 3% for one enclosure) could not be explained by the denitrification and/or dissolution of CaCO3 in the sediments, therefore suggesting the selectively faster decomposition of part of the organic matter provided through primary production, in other words, an accumulation of another part of the organic matter in the diurnal and/or daily time scale. 相似文献
78.
Fumihiro Fujiki Yoshihiro Oka Mai Kawakatsu Akihiro Tsuboi Hiroko Nakajima Olga A. Elisseeva Yukie Harada Zheyu Li Naoko Tatsumi Eriko Kamino Toshiaki Shirakata Sumiyuki Nishida Yuki Taniguchi Ichiro Kawase Yusuke Oji Haruo Sugiyama 《Microbiology and immunology》2008,52(12):591-600
The Wilms' tumor gene WT1 is overexpressed in various tumors, and the WT1 protein has been demonstrated to be an attractive target antigen for cancer immunotherapy. A WT1 protein‐derived 16‐mer peptide, WT1332 (KRYFKLSHLQMHSRKH), which was naturally generated through processing in cells and could elicit Th1‐type CD4+ helper T cell responses with an HLA‐DRB1*0405‐restriction has previously been identified by us. In the present study, it has been demonstrated that WT1332 can induce WT1332‐specific CD4+ T cell responses with the restriction of not only HLA‐DRB1*0405 but also HLA‐DRB1*1501, ‐DRB1*1502, or ‐DPB1*0901. These HLA class II‐restricted WT1332‐specific CD4+ T cell lines produced IFN‐γ but neither IL‐4 nor IL‐10 with WT1332 stimulation, thus showing a Th1‐type cytokine profile. Furthermore, HLA‐DRB1*1501 or ‐DRB1*1502‐restricted WT1332‐specific CD4+ T cell lines responded to WT1‐expressing transformed cells in an HLA‐DRB1‐restricted manner, which is consistent with our previous finding that WT1332 is a naturally processed peptide. These results indicate that the natural peptide, WT1332, is a promiscuous WT1‐specific helper epitope. WT1332 is expected to apply to cancer patients with various types of HLA class II as a WT1‐specific helper peptide in combination with HLA class I‐restricted WT1 peptides. 相似文献
79.
Onodera H Kaneko M Takahashi Y Uochi Y Funahashi J Nakashima T Soga S Suzuki M Ikeda S Yamashita Y Rahayu ES Kanda Y Ichimura M 《Bioorganic & medicinal chemistry letters》2008,18(5):1588-1591
Hsp90 is an attractive chemotherapeutic target because it is essential to maturation of multiple oncogenes. We describe the conformational significance of EH21A1-A4, phenolic derivatives of geldanamycin isolated from Streptomyces sp. Their native free structures are similar to the active form of geldanamycin bound to Hsp90 protein. Their conformational character is a probable reason for their high-affinity binding. Lack of toxic benzoquinone in EH21A1-A4 also adds to their potential as lead compounds for anti-tumor drugs. 相似文献
80.