78 research outputs found
コウシュウハ イオンプレーティング ホウ ニ ヨル ハクマク ケイセイ ニ カンスル ケンキュウ
The nanostructural hydrogenated graphite (CnanoHx) was synthesized from graphite by ball milling under hydrogen (H2) atmosphere. In this product, characteristic hydrogenated states in the form of polarized hydrocarbon groups (―CH, ―CH2, and ―CH3) are realized in the nanoscale. By synthesizing the composite of CnanoHx and lithium hydride (LiH), known as the Li―C―H system, hydrogen was desorbed at 350 °C, which is a lower temperature compared to the decomposition temperature of each component. It is considered that this hydrogen desorption would be induced by destabilization of each hydrogen absorbed state due to an interaction between the polarized C―H groups in CnanoHx and LiH. Therefore, in order to understand the hydrogen absorption/desorption mechanism of the Li―C―H system, it is an important issue to investigate the change in the C―H groups during hydrogen absorption/desorption reactions in the composite. The correlations among atoms contained in this composite are examined by neutron diffraction measurements, where the protium/deuterium (H/D) isotopic substitution was used to clarify the location of hydrogen atoms in this composite. Some C―D and Li―D correlations are found from the radial distribution function [RDF(r)] obtained by the neutron diffraction for the CnanoDx and LiD composite. After dehydrogenation, C―C triple bond and Li―C bond, ascribed to lithium carbide (Li2C2), are observed. Furthermore, the RDF(r) corresponding to rehydrogenated composite indicates the presence of not only the Li―D correlation but also the C―D one
シェーグレン症候群の新規自己抗原であるREG 蛋白の唾液導管細胞における発現誘導にはIL-6/STAT 経路が重要である
The regenerating gene, Reg, was originally isolated from a rat regenerating islet cDNA library, and its human homolog was named REG Iα. Recently, we reported that REG Iα mRNA as well as its product were overexpressed in ductal epithelial cells in the minor salivary glands of Sjögren׳s syndrome (SS) patients. This study was undertaken to elucidate the role of cytokines and the subsequent intracellular mechanism for induction of REG Iα in the salivary glands of SS patients. We prepared a reporter plasmid containing REG Iα promoter (−1190/+26) upstream of a luciferase reporter gene. The promoter plasmid was introduced by lipofection into human NS-SV-DC and rat A5 salivary ductal cells. The cells were treated with interleukin (IL)-6, IL-8, and a combination of the two. Thereafter transcriptional activity of REG Iα was measured by luciferase assay. We found that IL-6 stimulation, but not IL-8, significantly enhanced the REG Iα promoter activity in salivary ductal cells. Deletion analysis revealed that the region of −141 to −117 of the REG Iα gene was responsible for the promoter activation by IL-6, which contains a consensus sequence for signal transduction and activation of transcription (STAT). The introduction of siRNA for human STAT3 abolished IL-6-induced REG Iα transcription. These results showed that IL-6 stimulation induced REG Iα transcription through STAT3 activation and binding to the consensus sequence of REG Iα promoter in salivary ductal cells. This IL-6/STAT dependent REG Iα induction might play a role in the pathogenesis of SS.博士(医学)・甲第641号・平成27年11月27日Copyright © 2015 The Authors. Published by Elsevier B.V. This is an open access article under the CCBY-NC-ND
license (http://creativecommons.org/licenses/by-nc-nd/4.0/)
Interleukin-6/STAT pathway is responsible for the induction of gene expression of REG Iα, a new auto-antigen in Sjögren׳s syndrome patients, in salivary duct epithelial cells
The regenerating gene, Reg, was originally isolated from a rat regenerating islet cDNA library, and its human homolog was named REG Iα. Recently, we reported that REG Iα mRNA as well as its product were overexpressed in ductal epithelial cells in the minor salivary glands of Sjögren׳s syndrome (SS) patients. This study was undertaken to elucidate the role of cytokines and the subsequent intracellular mechanism for induction of REG Iα in the salivary glands of SS patients. We prepared a reporter plasmid containing REG Iα promoter (−1190/+26) upstream of a luciferase reporter gene. The promoter plasmid was introduced by lipofection into human NS-SV-DC and rat A5 salivary ductal cells. The cells were treated with interleukin (IL)-6, IL-8, and a combination of the two. Thereafter transcriptional activity of REG Iα was measured by luciferase assay. We found that IL-6 stimulation, but not IL-8, significantly enhanced the REG Iα promoter activity in salivary ductal cells. Deletion analysis revealed that the region of −141 to −117 of the REG Iα gene was responsible for the promoter activation by IL-6, which contains a consensus sequence for signal transduction and activation of transcription (STAT). The introduction of siRNA for human STAT3 abolished IL-6-induced REG Iα transcription. These results showed that IL-6 stimulation induced REG Iα transcription through STAT3 activation and binding to the consensus sequence of REG Iα promoter in salivary ductal cells. This IL-6/STAT dependent REG Iα induction might play a role in the pathogenesis of SS
Surface-Controlled Conversion of Ammonia Borane from Boron Nitride
“One-pot regeneration”, which is simple regneneration method of ammonia borane (AB) using hydrazine and liquid ammonia, enables conversion of AB from hexagonal boron nitride (h-BN) after milling hydrogenation. Solution ^B-NMR revealed the presence of AB after NH_3/N_2H_4 treatment of milled h-BN (BNH_x) although the yield of AB was less than 5%. The conversion mechanism was clarified as B-H bonds on the h-BN surface created by ball-milling under hydrogen pressure have an ability to form AB, which was confirmed by Thermogravimetry-Residual Gas Analysis (TG-RGA) and Infrared (IR) analysis. The reaction routes are also the same as regeneration route of polyborazylene because intermediates of AB such as (B(NH_2)_3 and hydrazine borane were found by solution ^B-NMR after soaking BNH_x in liquid NH_3 and hydrazine, respectively. Because of the fact that all reactions proceed on the h-BN surface and no reaction proceeds when neat h-BN is treated, breaking of B_3N_3 ring structure and then creation of B-H bond is the key issue to increase conversion yield of AB
Thermodynamic and structural properties of ball-milled mixtures composed of nano-structural graphite and alkali(-earth) metal hydride
Hydrogen desorption properties of mechanically milled materials composed of nano-structural hydrogenated-graphite (CnanoHx) and alkali(-earth) metal hydride (MH; M = Na, Mg and Ca) were investigated from the thermodynamic and structural points of view. The hydrogen desorption temperature for all the CnanoHx and MH composites was obviously lower than that of the corresponding each hydride. In addition, the desorption of hydrocarbons from CnanoHx was significantly suppressed by making composite of CnanoHx with MH, even though CnanoHx itself thermally desorbs a considerably large amount of hydrocarbons. These results indicate that an interaction exists between CnanoHx and MH, and hydrogen in both the phases is destabilized by a close contact between polar C-H groups in CnanoHx and the MH solid phase. Moreover, a new type of chemical bonding between the nano-structural carbon (Cnano) and the Li, Ca, or Mg metal atoms may be formed after hydrogen desorption. Thus, the above metal-C-H system would be recognized as a new family of H-storage materials
Database and data search system using \u27KANSEI\u27 words for aurora image files of DMSP satellites
Image Database Systems usually have some keywords selected by human decision. In recent years, it has been an interesting problem to develop a method by which shapes, colors and contents for a specific image from image files are recognized automatically through image processing. Furthermore, it becomes important to determine properly the keywords representing impression of images, that is, \u27KANSEI\u27 words. We try to construct a database and data search system of the DMSP satellite auroral image files. At first, an index file including information such as file name, size, date and geometric feature of images is created through image processing. The impressional items for auroral shapes such as brightness, position, and impression are derived by a coordinate conversion method so called the \u27KANSEI\u27 space method. The system contains about 100 image files and the index file. A specific image data is searched with the index file and the conversion method of \u27KANSEI\u27 words
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