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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
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Takimoto Yuki Monkawa Akira Nagata Kohki Kobayashi Masahiro Kinoshita Mariko Gessei Tomoko Mori Toshiya Kagi Hiroyuki 《Plasmonics (Norwell, Mass.)》2020,15(3):805-811
Plasmonics - Detection and monitoring of SO2 is important because it is a representative toxic gas in the atmospheric environment that is emitted from industrial and natural processes. Localized... 相似文献
136.
Masahiko Saito Tomohiro Fukuhara Satoshi Kamimura Hiroyuki Ichikawa Hiroyuki Yoshida Tomoyuki Koganezawa Yutaka Ie Yasunari Tamai Hyung Do Kim Hideo Ohkita Itaru Osaka 《Liver Transplantation》2020,10(7)
Controlling the energetics and backbone order of semiconducting polymers is essential for the performance improvement of polymer‐based solar cells. The use of fluorine as the substituent for the backbone is known to effectively deepen the molecular orbital energy levels and coplanarize the backbone by noncovalent interactions with sulfur of the thiophene ring. In this work, novel semiconducting polymers are designed and synthesized based on difluoronaphthobisthiadiazole (FNTz) as a new family of naphthobisthiadiazole (NTz)–quaterthiophene copolymer systems, which are one of the highest performing polymers in solar cells. The effect of the fluorination position on the energetics and backbone order is systematically studied. It is found that the dependence of the solar cell fill factor on the active layer thickness is very sensitive to the fluorination position. It is thus further investigated and discussed how the structural features of the polymers influence the photovoltaic parameters as well as the diode characteristics and bimolecular recombination. Further, the polymer with fluorine on both the naphthobisthiadiazole and quaterthiophene moieties exhibits a quite high power conversion efficiency of 10.8% in solar cells in combination with a fullerene. It is believed that the results would offer new insights into the development of semiconducting polymers. 相似文献
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Ao Tan Rio Suzuki Chikako Yokoyama Shigekazu Yano Hiroyuki Konno 《Journal of peptide science》2020,26(10)
A novel antimicrobial peptide derived from ovalbumin has been discovered. First, the peptide fragment RKIKVYLPRMK (TK9.1) was identified based on computerized predictions of the secondary structure of peptides in a protein data bank. Using HeliQuest, the sequence was developed into RKIKRYLRRMI (TK9.1.3), which was synthesized using Fmoc‐solid phase peptide synthesis, and found to have strongly antimicrobial activity against Gram‐positive and Gram‐negative bacteria, and fungi but not cytotoxic to HeLa cells and hemolysis in mouse red blood cells. Although ovalbumin itself does not have an antibacterial activity, our results suggest that it may supply the organisms that consume it with antimicrobial peptides, in support of their immunodefence. 相似文献
139.
Ichthyological Research - Lepadichthys coccinotaenia Regan 1921 (Gobiesocidae: Diademichthyinae) is redescribed on the basis of 60 specimens, including the holotype, and a new species of... 相似文献
140.
24S-hydroxycholesterol (HC) is most abundant oxysterols in the brain, passes through blood brain barrier, and is therefore regarded as an intermediary for brain cholesterol elimination. We reported that large-conductance Ca2+- and voltage-activated K+ (slo1 BK) channels are suppressed by this oxysterol, which is presumably intercalated into cell membrane to access the outer surface of the channel. Such an outer approach would make it difficult to interact with the inner, ion-conducting part of the channel. The present findings showed that 24R-HC, the racemic counterpart of 24S-HC, also suppressed slo1 BK channel but in a different voltage-dependent manner. There was a difference between the effects of the two enantiomers on activation kinetics but not on deactivation kinetics. It is suggested that the chirality contributes to the efficacy of channel blockers that act from outer lipophilic parts of channels, as with those which act on the inner, ion-permeable surface. 相似文献