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排序方式: 共有3099条查询结果,搜索用时 78 毫秒
991.
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993.
Tatsunori Masatani Tomohide Matsuo Tetsuya Tanaka Mohamad Alaa Terkawi Eung-Goo Lee Youn-Kyoung Goo Gabriel Oluga Aboge Junya Yamagishi Kei Hayashi Kyohko Kameyama Shinuo Cao Yoshifumi Nishikawa Xuenan Xuan 《Parasitology international》2013,62(4):372-379
Toxoplasma gondii is an intracellular protozoan parasite, which relies on a specialized compartment, the parasitophorous vacuole (PV), to survive within host cells. Dense granules within the parasite release a large variety of proteins to maintain the integrity of the vacuole structure. Here, we identified a novel dense granule protein in T. gondii, TgGRA23, which is a homolog of the Sarcocystis muris dense granule protein, SmDG32. Recombinant TgGRA23 (rTgGRA23) expressed in Escherichia coli as a glutathione S-transferase (GST) fusion protein was used to raise antisera in mice and rabbits. Immunoblotting showed that antisera from the immunized mice and rabbits reacted with parasite lysates to yield a 21-kDa native protein. In addition, immuno-electron microscopic examination showed that TgGRA23 resides in the dense granules, PV membrane and intravacuolar network of the parasite. To confirm the precise subcellular localization of TgGRA23 in T. gondii, an immunofluorescent antibody test was performed using dense granule markers. Notably, TgGRA23 co-localized with other dense granule proteins including TgGRA4 and TgGRA7, in the extracellular-stage parasites. Biochemical experiments indicated that TgGRA23 is insoluble and may form an electrostatic complex that is resistant to non-ionic detergents. Furthermore, specific antibodies to TgGRA23 were detected during the chronic stage of Toxoplasma infection in mice. Our results suggest that TgGRA23 is an as yet unknown member of the T. gondii dense granule proteins, and that it may be involved in remodeling or maintenance of the PV. 相似文献
994.
995.
Reactive oxygen species have various effects on the expression of cell adhesion molecules induced by pro-inflammatory cytokines, such as tumor necrosis factor f (TNF- f ). We studied the effects of monochloramine (NH 2 Cl), a physiological oxidant derived from activated neutrophils, on the TNF- f -induced expression of e-selectin and intercellular adhesion molecule-1 (ICAM-1) in human umbilical vein endothelial cells (HUVEC). HUVEC were pretreated with or without NH 2 Cl (20-90 w M for 20 min), then stimulated with TNF- f (10 ng/ml), and the expression of e-selectin and ICAM-1 was measured. Without NH 2 Cl, TNF- f induced marked expression of e-selectin and ICAM-1. Pretreatment with NH 2 Cl resulted in a significant, but transient inhibition of the expression of adhesion molecules. Higher dose of NH 2 Cl showed more pronounced inhibition, and the inhibitory effect lasted for 8 h when 70 w M of NH 2 Cl was added. TNF- f stimulation also induced marked activation of nuclear factor s B (NF- s B). Notably, NH 2 Cl also inhibited this NF- s B activation in a dose- and time-dependent manner, which was similar to the inhibition of e-selectin and ICAM-1 expression. In addition, I s B- f phosphorylation and degradation were also inhibited by NH 2 Cl pretreatment. These observations indicated that NH 2 Cl inhibited TNF- f -induced expression of e-selectin and ICAM-1 through the inhibition of NF- s B activation. We speculate that neutrophil-derived chloramines may have a regulatory role in the recruitment of leukocytes. 相似文献
996.
Yoshida Tomoyuki Takemoto Hiroyuki Sakamaki Tetsuya Tokuyama Nahoko Hart John Hart Terese Dupain Jef Cobden Amy Mulavwa Mbangi Hashimoto Chie Isaji Mina Kaneko Akihisa Enomoto Yuki Sato Eiji Kooriyama Takanori Miyabe-Nishiwaki Takako Suzuki Juri Saito Akatsuki Furuichi Takeshi Akari Hirofumi 《Primates; journal of primatology》2021,62(6):897-903
Primates - One of the current threats to the bonobo (Pan paniscus), a highly endangered ape species only found in the Democratic Republic of the Congo, are anthropozoonoses caused by human... 相似文献
997.
Sakata Masayuki K. Watanabe Takeshi Maki Nobutaka Ikeda Kousuke Kosuge Toshihiro Okada Hiroaki Yamanaka Hiroki Sado Tetsuya Miya Masaki Minamoto Toshifumi 《Limnology》2021,22(2):221-235
Limnology - In recent years, biodiversity loss has become one of the most serious environmental issues worldwide, especially in aquatic ecosystems. To avoid diversity loss, it is necessary to... 相似文献
998.
Sakamoto Keiji Tomonari Misaki Ariya Uyanga Nakagiri Erika Matsumoto Tetsuya K. Akaji Yasuaki Otoda Takashi Hirobe Muneto Nachin Baatarbileg 《Landscape and Ecological Engineering》2021,17(3):267-279
Landscape and Ecological Engineering - We aimed to test the hypothesis that large-scale forest fire followed by illegal logging inhibits the regeneration of boreal forests in Mongolia. For this... 相似文献
999.
1000.
Tomomi Kuwahara Yositoshi Ogura Kenshiro Oshima Ken Kurokawa Tadasuke Ooka Hideki Hirakawa Takehiko Itoh Haruyuki Nakayama-Imaohji Minoru Ichimura Kikuji Itoh Chieko Ishifune Yoichi Maekawa Koji Yasutomo Masahira Hattori Tetsuya Hayashi 《DNA research》2011,18(4):291-303
Numerous microbes inhabit the mammalian intestinal track and strongly impact host physiology; however, our understanding of this ecosystem remains limited owing to the high complexity of the microbial community and the presence of numerous non-culturable microbes. Segmented filamentous bacteria (SFBs), which are clostridia-related Gram-positive bacteria, are among such non-culturable populations and are well known for their unique morphology and tight attachment to intestinal epithelial cells. Recent studies have revealed that SFBs play crucial roles in the post-natal maturation of gut immune function, especially the induction of Th17 lymphocytes. Here, we report the complete genome sequence of mouse SFBs. The genome, which comprises a single circular chromosome of 1 620 005 bp, lacks genes for the biosynthesis of almost all amino acids, vitamins/cofactors and nucleotides, but contains a full set of genes for sporulation/germination and, unexpectedly, for chemotaxis/flagella-based motility. These findings suggest a triphasic lifestyle of the SFB, which comprises two types of vegetative (swimming and epicellular parasitic) phases and a dormant (spore) phase. Furthermore, SFBs encode four types of flagellin, three of which are recognized by Toll-like receptor 5 and could elicit the innate immune response. Our results reveal the non-culturability, lifestyle and immunostimulation mechanisms of SFBs and provide a genetic basis for the future development of the SFB cultivation and gene-manipulation techniques. 相似文献