Institution
University of Tsukuba
Education•Tsukuba, Ibaraki, Japan•
About: University of Tsukuba is a education organization based out in Tsukuba, Ibaraki, Japan. It is known for research contribution in the topics: Population & Gene. The organization has 36352 authors who have published 79483 publications receiving 1934752 citations. The organization is also known as: Tsukuba daigaku & Tsukuba University.
Topics: Population, Gene, Catalysis, Superconductivity, Quantum chromodynamics
Papers published on a yearly basis
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TL;DR: The results demonstrate that isoliquiritigenin and butein inhibit cell proliferation and induce apoptosis in B16 melanoma cells and it seems that the pathway by which the chalcones induce apoptose may be independent of p53 and dependent on proteins of the Bcl-2 family.
Abstract: We investigated the growth inhibitory activity of several flavonoids, including apigenin, luteolin, kaempherol, quercetin, butein, isoliquiritigenin, naringenin, genistein, and daizein against B16 mouse melanoma 4A5 cells. Isoliquiritigenin and butein, belonging to the chalcone group, markedly suppressed the growth of B16 melanoma cells and induced cell death. The other flavonoids tested showed little growth inhibitory activity and scarcely caused cell death. In cells treated with isoliquiritigenin or butein, condensation of nuclei and fragmentation of nuclear DNA, which are typical phenomena of apoptosis, were observed by Hoechst 33258 staining and by agarose gel electrophoresis of DNA. Flowcytometric analysis showed that isoliquiritigenin and butein increased the proportion of hypodiploid cells in the population of B16 melanoma cells. These results demonstrate that isoliquiritigenin and butein inhibit cell proliferation and induce apoptosis in B16 melanoma cells. Extracellular glucose decreased the proportion of hypodiploid cells that appeared as a result of isoliquiritigenin treatment. p53 was not detected in cells treated with either of these chalcones, however, protein of the Bcl-2 family were detected. The level of expression of Bax in cells treated with either of these chalcones was markedly elevated and the level of Bcl-XL decreased slightly. Isoliquiritigenin did not affect Bcl-2 expression, but butein down-regulated Bcl-2 expression. From these results, it seems that the pathway by which the chalcones induce apoptosis may be independent of p53 and dependent on proteins of the Bcl-2 family. It was supposed that isoliquiritigenin induces apoptosis in B16 cells by a mechanism involving inhibition of glucose transmembrane transport and promotion of Bax expression. On the other hand, it was suggested that butein induces apoptosis via down-regulation of Bcl-2 expression and promotion of Bax expression. This mechanism differs from the isoliquiritigenin induction pathway.
254 citations
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TL;DR: In this paper, an atypical guanine nucleotide exchange factor (DOCK2) was found to rapidly translocate to the plasma membrane in a phosphatidylinositol 3,4,5-trisphosphate-dependent manner.
Abstract: During chemotaxis, activation of the small guanosine triphosphatase Rac is spatially regulated to organize the extension of membrane protrusions in the direction of migration. In neutrophils, Rac activation is primarily mediated by DOCK2, an atypical guanine nucleotide exchange factor. Upon stimulation, we found that DOCK2 rapidly translocated to the plasma membrane in a phosphatidylinositol 3,4,5-trisphosphate-dependent manner. However, subsequent accumulation of DOCK2 at the leading edge required phospholipase D-mediated synthesis of phosphatidic acid, which stabilized DOCK2 there by means of interaction with a polybasic amino acid cluster, resulting in increased local actin polymerization. When this interaction was blocked, neutrophils failed to form leading edges properly and exhibited defects in chemotaxis. Thus, intracellular DOCK2 dynamics are sequentially regulated by distinct phospholipids to localize Rac activation during neutrophil chemotaxis.
253 citations
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TL;DR: In this article, the authors proposed an optimized Rh-ReO x /SiO 2 (Re/Rh = 0.5) catalyst with Re, Mo and W to increase the catalytic activity of glycerol hydrogenolysis using water as a solvent.
Abstract: Addition of Re, Mo and W to Rh/SiO 2 enhanced the catalytic activity of the glycerol hydrogenolysis using water as a solvent. The modification with Re gave the highest conversion and yield of 1,3-propanediol (1,3-PrD). The optimized Rh-ReO x /SiO 2 (Re/Rh = 0.5) catalyst maintained high selectivity to propanediols and suppressed C–C bond breaking even under low H 2 pressure and high reaction temperature, where Rh/SiO 2 is rather active to C–C bond breaking. Characterization results indicate the formation of ReO x clusters attached to the surface of Rh metal particles. This can cause the synergy between ReO x and Rh, and the glycerol hydrogenolysis proceeds on the interface between Rh metal surface and attached ReO x species.
253 citations
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TL;DR: In this article, the basic properties satisfied by elliptic genera in N = 2 theories are confirmed by some fundamental class of examples and a generic procedure to compute the elliptic genus of a particular class of orbifold theories, i.e., the ones orbifolds of e2πiJ0 in the Neveu-Schwarz sector.
253 citations
Authors
Showing all 36572 results
Name | H-index | Papers | Citations |
---|---|---|---|
Aaron R. Folsom | 181 | 1118 | 134044 |
Kazuo Shinozaki | 178 | 668 | 128279 |
Hyun-Chul Kim | 176 | 4076 | 183227 |
Masayuki Yamamoto | 171 | 1576 | 123028 |
Hua Zhang | 163 | 1503 | 116769 |
Lewis L. Lanier | 159 | 554 | 86677 |
David Cella | 156 | 1258 | 106402 |
Takashi Taniguchi | 152 | 2141 | 110658 |
Yoshio Bando | 147 | 1234 | 80883 |
Kazuhiko Hara | 141 | 1956 | 107697 |
Janet Rossant | 138 | 416 | 71913 |
Christoph Paus | 137 | 1585 | 100801 |
Kohei Miyazono | 135 | 515 | 68706 |
Craig Blocker | 134 | 1379 | 94195 |
Fumihiko Ukegawa | 133 | 1492 | 94465 |