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121.
Shin-Ichi Seki Hajime Takano Kazuto Kawakami Nobuhiko Kotaka Akira Endo Kenji Takehara 《Conservation Genetics》2007,8(5):1109-1121
The Japanese wood pigeon (Columba janthina) is endemic to the islands of East Asia and it is included in the Japanese and Asian Red Lists because of its narrow habitat
range that is restricted to mature forests on small islands and because of the destruction of these habitats. We examined
the genetic structure of Columba janthina by studying 463 base pairs of the mitochondrial control region sequences. We analyzed 154 samples from eight populations
and identified 27 haplotypes. Three population groups were identified based on the pairwise ΦST values. A substantial gene flow, as reflected by the low and non-significant ΦST values, is maintained among the northern group that includes six populations found on the Okinawa, Tokara, Goto, Setouchi,
Oki, and Izu islands. In contrast, the southeastern group found on the Ogasawara Islands had large ΦST values with every population from other regions (0.910 < ΦST < 0.962). The southwestern group found on the Sakishima Islands also had significant but small ΦST values with every population from the northern group (0.081 < ΦST < 0.205). The Mantel test showed a highly significant correlation between the ΦST values and the route length of the habitat network, as well as the linear distance with correction of the habitat gap effect,
indicating the importance of the closely connected structure of the habitats. The three groups mentioned above could be considered
as independent management units, and the southeastern group has the highest conservation priority due to its narrow distribution
range and small population size.
Electronic Supplementary Material The online version of this article (doi: ) contains supplementary material, which is available to authorized users. 相似文献
122.
TFE3 regulates muscle metabolic gene expression, increases glycogen stores, and enhances insulin sensitivity in mice 总被引:1,自引:0,他引:1
123.
Examination of conditions inhibiting the formation of acrylamide in the model system of fried potato
Ishihara K Matsunaga A Nakamura K Sakuma K Koga H 《Bioscience, biotechnology, and biochemistry》2006,70(7):1616-1621
Acrylamide (AAm) is produced in food through the reaction of asparagine and reducing sugar. We examined several methods of reducing the level of AAm using potato tubers. The fried model system that we employed consisted of thin slices that were first treated in water under different conditions before frying. A sufficient amount of water present in the fry material acts as an inhibitor against the formation of AAm and allows only a negligible amount of AAm to form. It was found that given the low content of water, the fry material temperature was sufficiently high to allow a relatively large level of AAm to form. Examination of water treatment prior to frying revealed that higher-temperature treatment water and longer treatment time resulted in the formation of lower levels of AAm. Moreover, removing some of the residual heat had an inhibiting effect on the formation of AAm. 相似文献
124.
Naka H Teruya K Bang JK Aimoto S Tatsumi T Konno H Nosaka K Akaji K 《Bioorganic & medicinal chemistry letters》2006,16(14):3761-3764
Core sequences necessary for substrate recognition and its inhibition at the PR/p3 site of HTLV-1 protease were clarified for the first time. From the cleavage rates of peptides containing a part of the PR/p3 site, a heptapeptide was found to be the minimal sequence required for substrate recognition. The use of synthetic inhibitors containing hydroxyethylamine dipeptide isostere indicated that a tetrapeptide sequence was necessary to achieve potent inhibition. 相似文献
125.
Hiroyuki Konno Saburo Aimoto Steven O. Smith Kazuto Nosaka Kenichi Akaji 《Bioorganic & medicinal chemistry》2009,17(16):5769-5774
N,N-Dimethyl-N-[4-[[[2-(4-methylphenyl)-6,7-dihydro-5H-benzocyclohepten-8-yl]carbonyl]amino]benzyl]tetrahydro-2H-pyran-4-aminium chloride (TAK779) is a potent and selective non-peptide CCR5 antagonist. To use a site-specifically labeled form as a molecular probe, TAK779 containing 13C at positions C19, 35, and 36 was produced. A commercially available [13C]-methyl iodide was employed for the labeling. Starting from a known carboxylic acid segment containing no labeled carbon, the labeled TAK779 was constructed by the successive coupling of [13C]-labeled tolyl boronic ester by the Suzuki–Miyaura reaction and a [13C]-labeled aniline segment by amide bond formation. 相似文献
126.
Satoru Yanagisawa Akira Koarai Hisatoshi Sugiura Tomohiro Ichikawa Masae Kanda Rie Tanaka Keiichiro Akamatsu Tsunahiko Hirano Kazuto Matsunaga Yoshiaki Minakata Masakazu Ichinose 《Respiratory research》2009,10(1):50
Background
Excessive oxidative stress has been reported to be generated in inflamed tissues and contribute to the pathogenesis of inflammatory lung diseases, exacerbations of which induced by viral infections are associated with toll-like receptor (TLR) activation. Among these receptors, TLR8 has been reported as a key receptor that recognizes single-strand RNA virus. However, it remains unknown whether TLR8 signaling is potentiated by oxidative stress. The aim of this study is to examine whether oxidative stress modulates TLR8 signaling in vitro.Methods
Human peripheral blood neutrophils were obtained from healthy non-smokers and stimulated with TLR 7/8 agonist imidazoquinoline resiquimod (R848) in the presence or absence of hydrogen peroxide (H2O2). Neutrophilic responses including cytokine release, superoxide production and chemotaxis were examined, and the signal transduction was also analyzed.Results
Activation of TLR8, but not TLR7, augmented IL-8 release. The R848-augmented IL-8 release was significantly potentiated by pretreatment with H2O2 (p < 0.01), and N-acetyl-L-cysteine reversed this potentiation. The combination of H2O2 and R848 significantly potentiated NF-kB phosphorylation and IkBα degradation. The H2O2-potentiated IL-8 release was suppressed by MG-132, a proteosome inhibitor, and by dexamethasone. The expressions of TLR8, myeloid differentiation primary response gene 88 (MyD88), and tumor necrosis factor receptor-associated factor 6 (TRAF6) were not affected by H2O2.Conclusion
TLR8-mediated neutrophilic responses were markedly potentiated by oxidative stress, and the potentiation was mediated by enhanced NF-kB activation. These results suggest that oxidative stress might potentiate the neutrophilic inflammation during viral infection. 相似文献127.
Akio Yamasaki Chizu Kameda Rui Xu Haruo Tanaka Takehiko Tasaka Nobuhito Chikazawa Hiroyuki Suzuki Takashi Morisaki Makoto Kubo Hideya Onishi Masao Tanaka Mitsuo Katano 《Cancer immunology, immunotherapy : CII》2010,59(5):675-686
Recently, it was reported that Hh signaling is activated in tumor stromal cells but not in tumor cells themselves and that stromal cells may play a role in the proliferation of cancer cells. This suggests the possibility that stromal cells have an important role in the proliferation of tumor cells that may be mediated through Hh signaling. In this report, we present for the first time that inflammation-stimulated monocytes produce Shh through activation of the NF-κB signaling pathway, and that the Shh produced promotes the proliferation of pancreatic cancer cells in a paracrine manner through Hh signaling. 相似文献
128.
Mutsumi Yokota Hiroshi Shitara Osamu Hashizume Kazuto Nakada Choji Taya Hiromichi Yonekawa 《FEBS letters》2010,584(18):3943-3948
To investigate the effects of respiration defects on the disease phenotypes, we generated trans-mitochondrial mice (mito-mice) by introducing a mutated G13997A mtDNA, which specifically induces respiratory complex I defects and metastatic potentials in mouse tumor cells. First, we obtained ES cells and chimeric mice containing the G13997A mtDNA, and then we generated mito-mice carrying the G13997A mtDNA via its female germ line transmission. The three-month-old mito-mice showed complex I defects and lactate overproduction, but showed no other phenotypes related to mitochondrial diseases or tumor formation, suggesting that aging or additional nuclear abnormalities are required for expression of other phenotypes. 相似文献
129.
Takuro Niidome Akira Ohga Yasuyuki Akiyama Kazuto Watanabe Yasuro Niidome Takeshi Mori Yoshiki Katayama 《Bioorganic & medicinal chemistry》2010,18(12):4453-4458
Gold nanorods exhibit strong absorbance of light in the near infrared region, which penetrates deeply into tissues. Since the absorbed light energy is converted into heat, gold nanorods are expected to act as a contrast agent for in vivo bioimaging and as a thermal converter for photothermal therapy. To construct a gold nanorod targeted delivery system for tumor a peptide substrate for urokinase-type plasminogen activator (uPA), expressed specifically on malignant tumors, was inserted between the PEG chain and the surface of the gold nanorods. In other words, we constructed PEG–peptide-modified gold nanorods. After mixing the gold nanorods with uPA, the PEG chain was released from the surface of the gold and subsequently nanorod aggregation took place. The formation of the aggregation was monitored as a decrease in light absorption at 900 nm. Tumor homogenate induced a significant decrease in this absorption. Larger amount of the PEG–peptide-modified gold nanorods bound to cells expressing uPA in vitro compared with control gold nanorods, which had scrambled sequence of the peptide. The PEG–peptide-modified gold nanorods showed higher accumulation in tumor than the control after they were injected intravenously into tumor-bearing mice, however, the density of the peptide on the surface of the gold nanorods was a key factor of their biodistributions. This targeted delivery system, which responds to uPA activity, is expected to be a powerful tool for tumor bioimaging and photothermal tumor therapy. 相似文献
130.
Umeda T Takashima N Nakagawa R Maekawa M Ikegami S Yoshikawa T Kobayashi K Okanoya K Inokuchi K Osumi N 《PloS one》2010,5(12):e15500
Autism is a highly variable brain developmental disorder and has a strong genetic basis. Pax6 is a pivotal player in brain development and maintenance. It is expressed in embryonic and adult neural stem cells, in astrocytes in the entire central nervous system, and in neurons in the olfactory bulb, amygdala, thalamus, and cerebellum, functioning in highly context-dependent manners. We have recently reported that Pax6 heterozygous mutant (rSey(2)/+) rats with a spontaneous mutation in the Pax6 gene, show impaired prepulse inhibition (PPI). In the present study, we further examined behaviors of rSey(2)/+ rats and revealed that they exhibited abnormality in social interaction (more aggression and withdrawal) in addition to impairment in rearing activity and in fear-conditioned memory. Ultrasonic vocalization (USV) in rSey(2)+ rat pups was normal in male but abnormal in female. Moreover, treatment with clozapine successfully recovered the defects in sensorimotor gating function, but not in fear-conditioned memory. Taken together with our prior human genetic data and results in other literatures, rSey(2)/+ rats likely have some phenotypic components of autism. 相似文献