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51.
Sumiko Hara Chisato Kaneko Hiroatsu Matsumoto Takeshi Nishino Tadao Takeuchi Takeo Mori 《Nucleosides, nucleotides & nucleic acids》2013,32(2-4):571-582
Abstract Novel β-D-ribofuranosides having a 5-substituted imidazo [4,5-d] [1,3]thiazine ring, including the S6-congener 3 of oxanosine 2, were synthesized for screening their anticancer and antiviral activities. 相似文献
52.
53.
Shimada E Kataoka H Miyazawa Y Yamamoto M Igarashi T 《Microbes and infection / Institut Pasteur》2012,14(11):916-921
Actinomyces viscosus has been suggested to be associated with periodontal disease. However, the pathogenicity of this bacterium is not known. In this study, we examined inflammation-inducing activity by A. viscosus. Whole cells and a lipophilic fraction of A. viscosus ATCC19246 induced production of interleukin-8 and tumor necrosis factor alpha from both human oral epithelial cells and human monocytoid cells. This cytokine production was blocked by lipoprotein lipase treatment of the lipophilic fraction. In addition, anti-Toll-like receptor 2 antibody blocked the cytokine production. These results suggest that lipoprotein of A. viscosus triggers inflammatory responses in periodontitis by activation of Toll-like receptor 2. 相似文献
54.
Satoshi N. Suzuki Masae I. Ishihara Masahiro Nakamura Shin Abe Tsutom Hiura Kosuke Homma Motoki Higa Daisuke Hoshino Kazuhiko Hoshizaki Hideyuki Ida Ken Ishida Motohiro Kawanishi Kazutaka Kobayashi Koichiro Kuraji Shigeo Kuramoto Takashi Masaki Kaoru Niiyama Mahoko Noguchi Haruto Nomiya Satoshi Saito Takeshi Sakai Michinori Sakimoto Hitoshi Sakio Tamotsu Sato Hirofumi Shibano Mitsue Shibata Maki Suzuki Atsushi Takashima Hiroshi Tanaka Masahiro Takagi Naoaki Tashiro Naoko Tokuchi Toshiya Yoshida Yumiko Yoshida 《Ecological Research》2012,27(6):989-990
This data paper reports litter fall data collected in a network of 21 forest sites in Japan. This is the largest litter fall data set freely available in Japan to date. The network is a part of the Monitoring Sites 1000 Project launched by the Ministry of the Environment, Japan. It covers subarctic to subtropical climate zones and the four major forest types in Japan. Twenty-three permanent plots in which usually 25 litter traps were installed were established in old-growth or secondary natural forests. Litter falls were collected monthly from 2004, and sorted into leaves, branches, reproductive structures and miscellaneous. The data provide seasonal patterns and inter-annual dynamics of litter falls, and their geographical patterns, and offer good opportunities for meta-analyses and comparative studies among forests. 相似文献
55.
Takashi Yamashita Naoto Tonouchi Takeshi Uozumi Teruhiko Beppu 《Molecular & general genetics : MGG》1987,210(3):462-467
Summary The aspartic protease gene of a zygomycete fungus Mucor pusillus was expressed in Saccharomyces cerevisiae under the control of the yeast GAL7 promoter. A putative preproenzyme with an NH2-terminal extension of 66 amino acids directed by the gene was processed in yeast cells and the mature enzyme, whose NH2-terminus was identical to that of the Mucor enzyme, was efficiently secreted into the medium at a concentration exceeding 150 mg/l. The enzyme secreted from the recombinant yeast was more glycosylated than the native Mucor enzyme but its enzymatic properties were almost identical with those of the native enzyme, which has been used as a milk coagulant in cheese manufacture. 相似文献
56.
57.
Toshiaki Nakano Rikiya Kamei Takashi Fujimura Yuki Takaoka Ayane Hori Chia-Yun Lai Kuei-Chen Chiang Yayoi Shimada Naoya Ohmori Takeshi Goto Kazuhisa Ono Chao-Long Chen Shigeru Goto Seiji Kawamoto 《PloS one》2016,11(4)
Nuclear antigens are known to trigger off innate and adaptive immune responses. Recent studies have found that the complex of nucleic acids and core histones that are derived from damaged cells may regulate allergic responses. However, no fundamental study has been performed concerning the role of linker histone H1 in mast cell-mediated type I hyperreactivity. In this study, we explored the impact of histone H1 on mast cell-mediated allergic responses both in vitro and in vivo. In the course of a bona-fide experimental allergen sensitization model upon co-injection with alum adjuvant, ovalbumin (OVA), but not PBS, induced elevated levels of circulating histone H1. Intranasal challenge with histone H1 to OVA/alum- (but not PBS/alum)-sensitized mice induced significantly severer symptoms of allergic rhinitis than those in mice sensitized and challenged with OVA. A monoclonal antibody against histone H1 not only suppressed mast cell degranulation, but also ameliorated OVA-induced nasal hyperreactivity and IgE-mediated passive cutaneous anaphylaxis. Our present data suggest that nuclear histone H1 represents an alarmin-like endogenous mediator acting on mast cells, and that its blockage has a therapeutic potential for mast cell-mediated type I hyperreactivity. 相似文献
58.
We examined the expression and functions of Pax1 and Pax9 in a teleost fish, the medaka Oryzias latipes. While Pax1 and Pax9 show distinct expression in the sclerotome in amniotes, we could not detect the differential expression of Pax1 and Pax9 in the developing sclerotome of the medaka. Furthermore, unlike the mouse, in which Pax1 is essential for development of the vertebral body, and where the neural arch is formed independent of either Pax1 or Pax9, our morpholino knockdown experiments revealed that both Pax1 and Pax9 are indispensable for the development of the vertebral body and neural arch. Therefore, we conclude that after gene duplication, Pax1 and Pax9 subfunctionalize their roles in the sclerotome independently in teleosts and amniotes. In Stage-30 embryo, Pax9 was strongly expressed in the posterior mesoderm, as was also observed for mouse Pax9. Since this expression was not detected for Pax1 in the mouse or fish, this new expression in the posterior mesoderm likely evolved in Pax9 of ancestral vertebrates after gene duplication. Two-month-old fish injected with Pax9 morpholino oligonucleotide showed abnormal morphology in the tail hypural skeletal element, which may have been related to this expression. 相似文献
59.
An Atg4B mutant hampers the lipidation of LC3 paralogues and causes defects in autophagosome closure
Fujita N Hayashi-Nishino M Fukumoto H Omori H Yamamoto A Noda T Yoshimori T 《Molecular biology of the cell》2008,19(11):4651-4659
In the process of autophagy, a ubiquitin-like molecule, LC3/Atg8, is conjugated to phosphatidylethanolamine (PE) and associates with forming autophagosomes. In mammalian cells, the existence of multiple Atg8 homologues (referred to as LC3 paralogues) has hampered genetic analysis of the lipidation of LC3 paralogues. Here, we show that overexpression of an inactive mutant of Atg4B, a protease that processes pro-LC3 paralogues, inhibits autophagic degradation and lipidation of LC3 paralogues. Inhibition was caused by sequestration of free LC3 paralogues in stable complexes with the Atg4B mutant. In mutant overexpressing cells, Atg5- and ULK1-positive intermediate autophagic structures accumulated. The length of these membrane structures was comparable to that in control cells; however, a significant number were not closed. These results show that the lipidation of LC3 paralogues is involved in the completion of autophagosome formation in mammalian cells. This study also provides a powerful tool for a wide variety of studies of autophagy in the future. 相似文献
60.
We have carried out a comprehensive survey of the spatiotemporal expression of cadherin superfamily genes in the basal chordate Ciona intestinalis, as an example of a genome-wide expression study of a gene family directly regulating cellular processes in morphogenesis. We found 15 definitely expressed cadherin superfamily genes in the Ciona intestinalis genome. Up to the late gastrula stage, all identified delta-protocadherins and the type II classical cadherin, but not other subfamily members, were zygotically expressed. At later stages, however, all cadherin superfamily genes were expressed in the nervous system. These data are useful for understanding the role of these genes in Ciona development and the evolution of chordates. 相似文献