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101.
The effects of glycolipids on the interaction of the MIF (migration inhibition factor) with rat macrophages were examined using a migration inhibition assay system. MIF activity was specifically blocked by fucosylated Glycolipid RM [Gal alpha 1-3Gal(2-1 alpha Fuc) beta 1-3GalNAc beta 1-3Gal beta 1-4Glc beta 1-1ceramide, (1978) J. Biochem. 83, 85-90], but not by Cytolipin R, hematoside, or blood group B active glycolipid [Gal alpha 1-3Gal(2-1 alpha Fuc) beta 1-4GlcNAc beta 1-3Gal beta 1-4Glc beta 1-1ceramide]. Inhibition of MIF activity was proportional to the concentration of Glycolipid RM. These findings suggest that Glycolipid RM acts as a receptor for MIF. 相似文献
102.
Propionylcholine, a novel analogue of acetylcholine, was identified in green plants by gas chromatography/mass spectrometry. Propionylcholine was found in the leaves of the following species previously shown to contain acetylcholine and cholinesterase activity: Codiaeum variegatum Blume, Phaseolus aureus Roxb. cv. Berken, Plantago rugelli Decne., Populus grandidentata Michx., and Betula pendula Roth. The quantities of propionylcholine ranged from a high of 2.3 nmol (g fresh weight)−1 in C. variegatum to a low of 0.11 nmol (g fresh weight)−1 in P. rugelli . These amounts represented 6 to 8% of the levels of acetylcholine. In contrast to animal tissues which rarely synthesize propionylcholine, this compound was found in all species examined which represented five families of flowering plants. 相似文献
103.
The immunostimulatory effects of the representative dental resin monomer 2-hydroxyethyl methacrylate (HEMA), a HEMA derivative that does not contain a double bond (2-hydroxyethyl isobutyrate, HEIB), and polymerized water-soluble oligomers of HEMA (PHEMA) were investigated. It is known that expression levels of either or both of CD54 and CD86 in THP-1 cells are increased by exposure to sensitizing substances. In this study, the expression levels of CD54 and CD86, the production of reactive oxygen species (ROS), and the viability of the cells were measured after 24 h of incubation with these materials at different concentrations. The concentrations of the materials that induced the expression of both CD54 and CD86 were low in the following order: NiSO4, HEMA, and methyl methacrylate (MMA). These results indicate that these dental resin monomers have lower sensitizing potentials than NiSO4. Although HEIB, which lacks a double bond, resulted in negligible ROS production and reduced cytotoxicity than HEMA, it induced the expression of CD54 and CD86. Comparison of the results for HEMA and HEIB indicates that dental resin monomer-induced sensitization may be related not only to the oxidative stress related to the methacryloyl group but also to the structures of these compounds. Of particular interest is the result that a water-soluble PHEMA oligomer with a relatively high-molecular weight also exhibited negligible cytotoxicity, whereas the expression level of CD54 increased after exposure to PHEMA at a high concentration. This result serves as a warning that polymerized substances also have the potential to induce sensitization. This study provides insight into the nature of allergic responses to dental resin materials in clinical use and may facilitate the development of more biocompatible restorative materials in the future. 相似文献
104.
Bo Zhang Akira Matsunaga David L. Rainwater Shin-ichiro Miura Keita Noda Hiroaki Nishikawa Yoshinari Uehara Kazuyuki Shirai Masahiro Ogawa Keijiro Saku 《Journal of lipid research》2009,50(9):1832-1841
Electronegative LDL, a charge-modified LDL (cm-LDL) subfraction that is more negatively charged than normal LDL, has been shown to be inflammatory. We previously showed that pravastatin and simvastatin reduced the electronegative LDL subfraction, fast-migrating LDL (fLDL), as analyzed by capillary isotachophoresis (cITP). The present study examined the effects of rosuvastatin on the more electronegative LDL subfraction, very-fast-migrating LDL (vfLDL), and small, dense charge-modified LDL (sd-cm-LDL) subfractions. Patients with hypercholesterolemia or those who were being treated with statins (n = 81) were treated with or switched to 2.5 mg/d rosuvastatin for 3 months. Rosuvastatin treatment effectively reduced cITP cm-LDL subfractions of LDL (vfLDL and fLDL) or sdLDL (sd-vfLDL and sd-fLDL), which were closely related to each other but were different from the normal subfraction of LDL [slow-migrating LDL (sLDL)] or sdLDL (sd-sLDL) in their relation to the levels of remnant-like particle cholesterol (RLP-C), apolipoprotein (apo) C-II, and apoE. The percent changes in cm-LDL or sd-cm-LDL caused by rosuvastatin were correlated with those in the particle concentrations of LDL or sdLDL measured as LDL-apoB or sdLDL-apoB and the levels of HDL-C, RLP-C, apoC-II, and apoE. In conclusion, rosuvastatin effectively reduced both the vfLDL subfraction and sd-cm-LDL subfractions as analyzed by cITP. 相似文献
105.
A mixture of NADPH and ferredoxin reductase is a convenient way of reducing adriamycin in vitro. Under aerobic conditions the adriamycin semiquinone reacts rapidly with O2 and superoxide radical is produced. Superoxide generated either by adriamycin:ferredoxin reductase or by hypoxanthine:xanthine oxidase can promote the formation of hydroxyl radicals in the presence of soluble iron chelates. Hydroxyl radicals produced by a hypoxanthine:xanthine oxidase system in the presence of an iron chelate cause extensive fragmentation in double-stranded DNA. Protection is offered by catalase, superoxide dismutase or desferrioxamine. Addition of double-stranded DNA to a mixture of adriamycin, ferredoxin reductase, NADPH and iron chelate inhibits formation of both superoxide and hydroxyl radicals. This is not due to direct inhibition of ferredoxin reductase and single-stranded DNA has a much weaker inhibitory effect. It is concluded that adriamycin intercalated into DNA cannot be reduced. 相似文献
106.
Synthetic oligodeoxyribonucleotides showing abnormal mobilities on polyacrylamide gel electrophoresis 总被引:3,自引:0,他引:3
We found that synthetic DNA fragments containing a GCGAAAGC sequence showed higher mobilities than oligonucleotides without the sequence on denaturing polyacrylamide gel electrophoresis. For example, the fragment, GCGAAAGCT (9mer), showed higher mobility than the corresponding 8mer (CGAAAGCT). In addition, on Maxam-Gilbert sequencing, a 21mer containing the GCGAAAGC sequence showed an abnormal pattern, which were similar to those due to compression observed on sequencing of DNAs with high GC contents, as recently reported. It was suggested that this compression was due to the increased mobilities of the specific fragments with the GCGAAAGC sequence and that these fragments took on abnormal conformations. 相似文献
107.
Takemura Aya Matsumoto Junya Hashimoto Ryota Kawano Kenji Miura Kenichiro 《Journal of computational neuroscience》2021,49(3):273-282
Journal of Computational Neuroscience - When two-frame apparent motion stimuli are presented with an appropriate inter-stimulus interval (ISI), motion is perceived in the direction opposite to the... 相似文献
108.
Diacylglycerol kinase (DGK) η translocates from the cytoplasm to punctate vehicles via osmotic shock. Apoptosis signal-regulating kinase (ASK) 3 (MAP kinase kinase kinase (MAPKKK) 15) is also reported to respond to osmotic shock. Therefore, in the present study, we examined the subcellular localization of DGKη and ASK3 expressed in COS-7 cells under osmotic stress. We found that DGKη was almost completely colocalized with ASK3 in punctate structures in response to osmotic shock. In contrast, DGKδ, which is closely related to DGKη structurally, was not colocalized with ASK3, and DGKη failed to colocalize with another MAPKKK, C-Raf, even under osmotic stress. The structures in which DGKη and ASK3 localized were not stained with stress granule makers. Notably, DGKη strongly interacted with ASK3 in an osmotic shock-dependent manner. These results indicate that DGKη and ASK3 undergo osmotic shock-dependent colocalization and associate with each other in specialized structures. 相似文献
109.
Mayumi Yoshihara Hiroshi Akasaka Hirofumi Ohnishi Takayuki Miki Tetsuaki Furukawa Satoshi Yuda Shigeyuki Saitoh Tetsuji Miura 《PloS one》2013,8(7)
Aims
Roles of glucagon-like peptide-1 (GLP-1) in extra-pancreatic tissues remain unclear. The aim of this study was to examine determinants of GLP-1 secretory function and possible contribution of GLP-1 to blood pressure (BP) regulation.Methods and Results
We recruited 128 subjects who received annual examinations and 75g-oral glucose tolerance tests (OGTT) in the Tanno-Sobetsu cohort. Subjects on regular medications for cardiovascular and/or metabolic diseases were excluded, and data for the remaining 103 subjects were used for the univariate and multivariate analyses. Age, plasma glucose (PG), hemoglobin A1c (HbA1c), plasma insulin, and serum lipids were not selected as independent determinants of fasting GLP-1 level by multiple linear regression analysis. However, age and female sex were selected as independent positive determinants of the area under the curve of GLP-1 level during OGTT (AUCGLP-1), an index of GLP-1 secretory function. Multiple linear regression analysis indicated that AUCGLP-1 was an independent negative predictor of systolic BP (SBP), while AUCGLP-1 was not correlated with fasting PG or HbA1c level. In subgroup analyses using the median of AUCGLP-1 to divide the study subjects into high and low GLP-1 response groups, AUCGLP-1 was significantly correlated with both SBP and diastolic BP (r = 0.40 and 0.28, respectively) in the low GLP-1 response group but not in the high GLP-1 response group.Conclusions
The results of the present study suggest that GLP-1 secretory function is involved in prevention of BP elevation and that the GLP-1 response to oral glucose rather increases with aging perhaps as an adaptive phenomenon. 相似文献110.
Shutaro Ishimura Masato Furuhashi Yuki Watanabe Kyoko Hoshina Takahiro Fuseya Tomohiro Mita Yusuke Okazaki Masayuki Koyama Marenao Tanaka Hiroshi Akasaka Hirofumi Ohnishi Hideaki Yoshida Shigeyuki Saitoh Tetsuji Miura 《PloS one》2013,8(11)