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891.
Sarkar M.A. Kawsar Tomoharu Takeuchi Ken-ichi Kasai Yuki Fujii Ryo Matsumoto Hidetaro Yasumitsu Yasuhiro Ozeki 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2009,152(4):382-389
A lectin recognizing D-galactose was purified from the pacific annelid Perinereis nuntia ver. vallata (Polychaeta) by affinity chromatography. Hemagglutinating activity, with a very low titer suggesting the presence of lectin appeared in the supernatant from the homogenization of body with Tris-buffered saline. However, dialyzed supernatant from the precipitate homogenized by galactose in the buffer revealed strong hemagglutinating activity against human erythrocytes. The crude supernatant was applied onto lactosyl–agarose column, and only the supernatant eluted from precipitate with galactose was obtained a galactose-binding lectin with 32 kDa polypeptide was obtained from the supernatant of the precipitate, extracted in presence of galactose. It suggests that the lectin tightly binds with glycoconjugate as endogenous ligand(s) in the tissue. Hemagglutinating activity against trypsinized and glutaraldehyde-fixed human erythrocytes was specifically inhibited by D-galactose, N-acetyl-D-galactosamine, lactose, melibiose, and asialofetuin. Glycan-binding profile of the lectin analyzed by frontal affinity chromatography shows that the lectin recognizes branched complex type N-linked oligosaccharides and both type 1 (Galβ1-3GlcNAc) and type 2 (Galβ1-4GlcNAc) lactosamine. The surface plasmon resonance study of the lectin against asialofetuin showed the kass and kdiss values are 5.14 × 104 M− 1 s− 1 and 2.9 × 10−3 s− 1, respectively. The partial primary structure of the lectin reveals 182 amino acids with novel sequence. 相似文献
892.
Koji Tominaga Katsutoshi Watanabe Ryo Kakioka Seiichi Mori Sang-Rin Jeon 《Ichthyological Research》2009,56(2):195-199
To elucidate the genetic population structure of Pseudogobio esocinus (Cyprinidae) in central Honshu, Japan, we performed phylogeographic analysis based on partial mitochondrial cytochrome b gene sequences. We found not only differentiation of mtDNA lineages between basins (uncorrected p ≈ 2%), presumably associated with uplifting of the Suzuka Mountains in the early Pleistocene, but also more diverged two
mtDNA lineages within basins (p ≈ 8%). No evidence of mtDNA introgression from related sympatric species was found. The phylogeographic history of these
two lineages should be elucidated by further analysis based on the specimens of P. esocinus from the entire distribution range. 相似文献
893.
Nakanishi H Iida Y Shimizu T Taguchi R 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2009,877(13):1366-1374
Recently, it was reported that oxidized phosphatidylcholine shows biological activities via scavenger receptor CD36 or Toll-like receptor 4 (TLR4)-TRIF. Thus, the analysis of oxidized phospholipids is essential in understanding these biological roles. Here, we report an analytical method for oxidized phosphatidylcholines using multiple reaction monitoring (MRM) with theoretically expanded data sets. This analytical method was performed by a quadrupole linear ion trap mass spectrometer with ultra performance LC (UPLC). To investigate whether this established analytical method was applicable to biological samples, we performed variation analysis of oxidized PCs using a myocardial ischemia-reperfusion model. Most oxidized PCs were detected in higher amounts in the ischemic myocardium than in the non-ischemic myocardium. From these application results, this established method is a valuable tool for the global analysis of oxidized PCs. In the future, our study can provide further understanding of how oxidized phospholipids are produced and are correlated to various diseases. 相似文献
894.
Hideo Nakanishi Ryo Yamada Norimoto Gotoh Hisako Hayashi Kenji Yamashiro Noriaki Shimada Kyoko Ohno-Matsui Manabu Mochizuki Masaaki Saito Tomohiro Iida Keitaro Matsuo Kazuo Tajima Nagahisa Yoshimura Fumihiko Matsuda 《PLoS genetics》2009,5(9)
Myopia is one of the most common ocular disorders worldwide. Pathological myopia, also called high myopia, comprises 1% to 5% of the general population and is one of the leading causes of legal blindness in developed countries. To identify genetic determinants associated with pathological myopia in Japanese, we conducted a genome-wide association study, analyzing 411,777 SNPs with 830 cases and 1,911 general population controls in a two-stage design (297 cases and 934 controls in the first stage and 533 cases and 977 controls in the second stage). We selected 22 SNPs that showed P-values smaller than 10−4 in the first stage and tested them for association in the second stage. The meta-analysis combining the first and second stages identified an SNP, rs577948, at chromosome 11q24.1, which was associated with the disease (P = 2.22×10−7 and OR of 1.37 with 95% confidence interval: 1.21–1.54). Two genes, BLID and LOC399959, were identified within a 200-kb DNA encompassing rs577948. RT–PCR analysis demonstrated that both genes were expressed in human retinal tissue. Our results strongly suggest that the region at 11q24.1 is a novel susceptibility locus for pathological myopia in Japanese. 相似文献
895.
Management units of the endangered herb Primula sieboldii based on microsatellite variation among and within populations throughout Japan 总被引:1,自引:0,他引:1
Masanori Honjo Naoko Kitamoto Saneyoshi Ueno Yoshihiko Tsumura Izumi Washitani Ryo Ohsawa 《Conservation Genetics》2009,10(2):257-267
To promote programs for the conservation and restoration of the endangered species Primula sieboldii, we examined genetic variation at eight microsatellite loci among and within 32 remnant wild populations throughout Japan.
Total allelic diversity within a population was higher in larger populations, but not so after rarefaction adjustment. The
positive relationship between population size and the inbreeding coefficient may suggest that more heterozygous genets tend
to survive the habitat contraction possibly because of the higher fitness associated with heterozygosity. By principal coordinate
analysis and Bayesian analysis, we detected four genetic groups (Hokkaido, northern Honshu, central Honshu, and western Japan),
which could be recognized as management units of P. sieboldii. If supplementation with plants from other populations were planned, it should be conducted among populations which belong
to the same management unit and which are likely to represent the same adaptive variation. 相似文献
896.
Developing biodiversity indicators for cities: applying the DPSIR model to Nagoya and integrating social and ecological aspects 总被引:2,自引:0,他引:2
Ryo Kohsaka 《Ecological Research》2010,25(5):925-936
Capturing the trends and status of urban biodiversity is challenged by current rapid changes, including increasing population
flow into urban areas and multiple pressures on neighboring ecosystems. For this reason, this article aims to highlight relevant
findings from both ecological and social sciences in the development of urban and biodiversity indicators. It examines the
applicability of a model to an urban city in Japan. The objectives of this study are threefold. First, it reviews and summarizes
the historical development and relevant existing studies of urban and biodiversity indicators, the “Drivers-Pressure-State-Impact-Response”
(DPSIR) model is presented, and its main critiques are summarized. Second, trends in scientific studies in specific journals
are identified. Third, practical lessons for a Japanese local municipality, the city of Nagoya, are derived from two previous
sets of reviews. The applicability of the “DPSIR” to current practices in the city of Nagoya is examined to assess the relevance
of the model to real situations. 相似文献
897.
Kenji Yamashiro Tetsuo Sasano Iyuki Namekata Naoki Sawada Takayoshi Suganami Hikaru Tanaka Kazunori Utsunomiya Tetsushi Furukawa 《Biochemical and biophysical research communications》2010,398(2):284-11436
There is considerable evidence indicating that intracellular Ca2+ participates as a second messenger in TLR4-dependent signaling. However, how intracellular free Ca2+ concentrations ([Ca2+]i) is increased in response to LPS and how they affect cytokine production are poorly understood. Here we examined the role of transient receptor potential (TRP), a major Ca2+ permeation pathway in non-excitable cells, in the LPS-induced cytokine production in macrophages. Pharmacologic experiments suggested that TRPV family members, but neither TRPC nor TRPM family members, are involved in the LPS-induced TNFα and IL-6 production in RAW264 macrophages. RT-PCR and immunoblot analyses showed that TRPV2 is the sole member of TRPV family expressed in macrophages. ShRNA against TRPV2 inhibited the LPS-induced TNFα and IL-6 production as well as IκBα degradation. Experiments using BAPTA/AM and EGTA, and Ca2+ imaging suggested that the LPS-induced increase in [Ca2+]i involves both the TRPV2-mediated intracellular and extracellular Ca2+ mobilizations. BAPTA/AM abolished LPS-induced TNFα and IL-6 production, while EGTA only partially suppressed LPS-induced IL-6 production, but not TNFα production. These data indicate that TRPV2 is involved in the LPS-induced Ca2+ mobilization from intracellular Ca2+ store and extracellular Ca2+. In addition to Ca2+ mobilization through the IP3-receptor, TRPV2-mediated intracellular Ca2+ mobilization is involved in NFκB-dependent TNFα and IL-6 expression, while extracellular Ca2+ entry is involved in NFκB-independent IL-6 production. 相似文献
898.
899.
900.
Hikaru Suenaga Kazuhiko Nonaka Hidehiko Fujihara Masatoshi Goto Kensuke Furukawa 《Applied microbiology and biotechnology》2010,88(4):915-923
Pseudomonas pseudoalcaligenes KF707 possesses a chromosomally encoded bph gene cluster responsible for the catabolism of biphenyl and polychlorinated biphenyls. Previously, we constructed chimeric
versions of the bphA1 gene, which encodes a large subunit of biphenyl dioxygenase, by using DNA shuffling between bphA1 genes from P. pseudoalcaligenes KF707 and Burkholderia xenovorans LB400. In this study, we demonstrate replacement of the bphA1 gene with chimeric bphA1 sequence within the chromosomal bph gene cluster by two-step homologous recombination. Notably, some of the hybrid strains acquired enhanced and/or expanded
degradation capabilities for specific aromatic compounds, including single aromatic hydrocarbons and polychlorinated biphenyls. 相似文献