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51.
Fumiyuki Nakagawa Katsutaro Morino Satoshi Ugi Atsushi Ishikado Keiko Kondo Daisuke Sato Shiho Konno Ken-ichi Nemoto Chisato Kusunoki Osamu Sekine Akihiro Sunagawa Masanori Kawamura Noriko Inoue Yoshihiko Nishio Hiroshi Maegawa 《Biochemical and biophysical research communications》2014
It has recently been reported that expression of heme oxygenase-1 (HO-1) plays a protective role against many diseases. Furthermore, n-3 polyunsaturated fatty acids (PUFAs) were shown to induce HO-1 expression in several cells in vitro, and in a few cases also in vivo. However, very few reports have demonstrated that n-3 PUFAs induce HO-1 in vivo. 相似文献
52.
53.
Kimi Araki Naoki Takeda Atsushi Yoshiki Yuichi Obata Naomi Nakagata Toshihiko Shiroishi Kazuo Moriwaki Ken-ichi Yamamura 《Mammalian genome》2009,20(1):14-20
MSM/Ms is an inbred mouse strain established from the Japanese wild mouse, Mus musculus molossinus, which has been phylogenetically distinct from common laboratory mouse strains for about 1 million years. The nucleotide
substitution rate between MSM/Ms and C57BL/6 is estimated to be 0.96%. MSM/Ms mice display unique characteristics not observed
in the commonly used laboratory strains, including an extremely low incidence of tumor development, high locomotor activity,
and resistance to high-fat-diet-induced diabetes. Thus, functional genomic analyses using MSM/Ms should provide a powerful
tool for the identification of novel phenotypes and gene functions. We report here the derivation of germline-competent embryonic
stem (ES) cell lines from MSM/Ms blastocysts, allowing genetic manipulation of the M. m. molossinus genome. Fifteen blastocysts were cultured in ES cell medium and three ES lines, Mol/MSM-1, -2, and -3, were established.
They were tested for germline competency by aggregation with ICR morulae and germline chimeras were obtained from all three
lines. We also injected Mol/MSM-1 ES cells into blastocysts of ICR or C57BL/6 × BDF1 mice and found that blastocyst injection
resulted in a higher production rate of chimeric mice than did aggregation. Furthermore, Mol/MSM-1 subclones electroporated
with a gene trap vector were also highly efficient at producing germline chimeras using C57BL/6 × BDF1 blastocyst injection.
This Mol/MSM-1 ES line should provide an excellent new tool allowing the genetic manipulation of the MSM/Ms genome. 相似文献
54.
The ultrastructure of the purified and lyophilized endotoxin from Escherichia coli O111 was observed by ultrathin sectioning. Onion-like globular membrane structures were observed in addition to rod-like and ribbon-like structures, indicating the existence of a globular membrane structure even in the dried state. 相似文献
55.
Haruhiko Tokuda Jun Kotoyori Atsushi Suzuki Yutaka Oiso Osamu Kozawa 《Journal of cellular biochemistry》1993,52(2):220-226
We investigated the effects of vitamin D3 on the signaling pathways by prostaglandin E2 (PGE2) in osteoblast-like MC3T3-E1 cells. The pretreatment with 1,25-dihydroxyvitamin D3 (1,25-(OH)2D3), an active form of vitamin D3, significantly inhibited cAMP accumulation induced by 10 μM PGE2 in a dose-dependent manner in the range between 1 pM and 1 nM. This effect of 1,25-(OH)2D3 was dependent on the time of pretreatment up to 8 h. 1,25-(OH)2D3 also inhibited the cAMP accumulation induced by NaF, a GTP-binding protein activator, or forskolin which directly activates adenylate cyclase. On the other hand, 1,25-(OH)2D3 significantly inhibited PGE2-induced IP3 formation in a dose-dependent manner between 10 pM and 1 nM. However, 1,25-(OH)2D3 had little effect on NaF-induced IP3 formation. The pretreatment with 24,25-dihydroxyvitamin D3, an inactive form of vitamin D3, affected neither cAMP accumulation nor IP3 formation induced by PGE2. These results strongly suggest that 1,25-(OH)2D3 modulates the signaling by PGE2 in osteoblast-like cells as follows: the inhibitory effect on the cAMP production is exerted at a point downstream from adenylate cyclase and the inhibitory effect on the phosphoinositide hydrolysis is exerted at the point between the PGE2 receptor and GTP-binding protein, probably Gi2. 相似文献
56.
Autophagy is an evolutionarily conserved mechanism for protein degradation that is critical for the maintenance of homeostasis in man. Autophagy has unexpected pleiotropic functions that favor survival of the cell, including nutrient supply under starvation, cleaning of the cellular interior, defense against infection and antigen presentation. Moreover, defective autophagy is associated with a diverse range of disease states, including neurodegeneration, cancer and Crohn's disease. Here we discuss the roles of mammalian autophagy in health and disease and highlight recent advances in pharmacological manipulation of autophagic pathways as a therapeutic strategy for a variety of pathological conditions. 相似文献
57.
Miura T Fukami TA Hasegawa K Ono N Suda A Shindo H Yoon DO Kim SJ Na YJ Aoki Y Shimma N Tsukuda T Shiratori Y 《Bioorganic & medicinal chemistry letters》2011,21(19):5778-5783
Heat shock protein 90 (Hsp90) is a molecular chaperone which regulates maturation and stabilization of its substrate proteins, known as client proteins. Many client proteins of Hsp90 are involved in tumor progression and survival and therefore Hsp90 can be a good target for developing anticancer drugs. With the aim of efficiently identifying a new class of orally available inhibitors of the ATP binding site of this protein, we conducted fragment screening and virtual screening in parallel against Hsp90. This approach quickly identified 2-aminotriazine and 2-aminopyrimidine derivatives as specific ligands to Hsp90 with high ligand efficiency. In silico evaluation of the 3D X-ray Hsp90 complex structures of the identified hits allowed us to promptly design CH5015765, which showed high affinity for Hsp90 and antitumor activity in human cancer xenograft mouse models. 相似文献
58.
Kazuo Imai Norihito Tarumoto Kiyoko Amo Makoto Takahashi Naoya Sakamoto Atsushi Kosaka Yasuyuki Kato Kei Mikita Jun Sakai Takashi Murakami Yutaka Suzuki Shigefumi Maesaki Takuya Maeda 《Parasitology international》2018,67(1):34-37
Cutaneous leishmaniasis (CL) is gaining attention as a public health problem. We present two cases of CL imported from Syria and Venezuela in Japan. We diagnosed them as CL non-invasively by the direct boil loop-mediated isothermal amplification method and an innovative sequencing method using the MinION? sequencer. This report demonstrates that our procedure could be useful for the diagnosis of CL in both clinical and epidemiological settings. 相似文献
59.
Cloning and nucleotide sequence of the mono- and diacylglycerol lipase gene (mdlB) of Aspergillus oryzae 总被引:1,自引:0,他引:1
Atsushi Tsuchiya Hidekazu Nakazawa Jinichi Toida Kunio Ohnishi Junichi Sekiguchi 《FEMS microbiology letters》1996,143(1):63-67
Abstract Aspergillus oryzae IFO4202 produces at least two extracellular lipolytic enzymes L1 and L2 (cutinase, and mono- and diacylglycerol lipase, respectively). Southern hybridization of restriction enzyme-digested genomic DNA fragments with 23mer oligonucleotides synthesized according to the amino acid sequence of the L2 as probe suggested the presence of the L2 gene (tentatively designated as mdlB ) and an additional weakly hybridizing region. A fragment containing the genomic mdlB gene was cloned in Escherichia coli . Nucleotide sequencing of the fragment revealed an open reading frame, comprising 1021 nucleotides, which contains two introns (51 and 52 nucleotides). Putative polyadenylation signals were found 182 and 287 bp downstream of the stop codon. The deduced amino acid sequence of the mdlB gene corresponds to 306 amino acid residues including a leader sequence of 28 amino acids and is highly similar to that of the mdlA gene of Penicillium camembertii . Three residues presumed to form the catalytic triad (serine, aspartic acid and histidine) of lipases were also conserved. 相似文献
60.
A case for regulatory B cells 总被引:11,自引:0,他引:11
B cells are typically characterized by their ability to produce Abs, including autoantibodies. However, B cells possess additional immune functions, including the production of cytokines and the ability to function as a secondary APC. As with T cells, the B cell population contains functionally distinct subsets capable of performing both pathogenic and regulatory functions. Recent studies indicate that regulatory B cells develop in several murine models of chronic inflammation, including inflammatory bowel disease, rheumatoid arthritis, and experimental autoimmune encephalomyelitis. The regulatory function may be directly accomplished by the production of regulatory cytokines IL-10 and TGF-beta and/or by the ability of B cells to interact with pathogenic T cells to dampen harmful immune responses. In this review, we make a case for the existence of regulatory B cells and discuss the possible developmental pathways and functional mechanisms of these B cells. 相似文献