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991.
Suzuki T Nagano Y Matsuura A Kohara A Ninomiya S Kohda K Miyata N 《Bioorganic & medicinal chemistry letters》2003,13(24):4321-4326
In order to find novel non-hydroxamate histone deacetylase (HDAC) inhibitors, a series of compounds modeled after suberoylanilide hydroxamic acid (SAHA) were designed and synthesized as (i) substrate (acetyl lysine) analogues (compounds 3–7), (ii) analogues bearing various functional groups expected to chelate zinc ion (compounds 8–15), and (iii) analogues bearing nucleophilic functional groups which could bind covalently to HDACs (compounds 16–18). In this series, semicarbazide 8b and bromoacetamides 18b,c were found to be potent HDAC inhibitors for non-hydroxamates. 相似文献
992.
993.
Shohei?NakamuraEmail author Takatoshi?Sakamoto Tomonori?Ito Kazuhiro?Kabasawa Hiroshi?Yuasa 《AAPS PharmSciTech》2016,17(6):1393-1403
Wet coating methods use organic solvents to prepare layered particles that provide controlled-release medications. However, this approach has disadvantages in that it can cause particle agglomeration, reduce pharmaceutical stability, and leave residual organic solvents. We used a dry coating method to overcome these issues. Fine particles (less than 50 μm in diameter) of controlled-release theophylline were created using theophylline (TP; model drug), polyethylene glycol 20,000 (PEG; drug fixative), hydrogenated castor oil (HCO; controlled-release material), hydrogenated rapeseed oil (HRSO; controlled-release material), and cornstarch (CS; core particle). An ultrahigh-speed mixer was employed to mix TP and CS for 5 min at 28,000 rpm. Subsequent addition of PEG produced single-core particles with a drug reservoir coating. Addition of HCO and HRSO to these particles produced a controlled-release layer on their surface, resulting in less than 10% TP dissolution after 8 h. We successfully demonstrated that this dry coating method could be used to coat 16-μm CS particles with a drug reservoir layer and a controlled-release layer, producing multi-layer coated single-core particles that were less than 50 μm in diameter. These can be used to prepare controlled-release tablets, capsules, and orally disintegrating tablets. 相似文献
994.
Takamasa Ishizuka Paulraj Kanmani Hisakazu Kobayashi Ayako Miyazaki Junichi Soma Yoshihito Suda Hisashi Aso Tomonori Nochi Noriyuki Iwabuchi Jin-zhong Xiao Tadao Saito Julio Villena Haruki Kitazawa 《PloS one》2016,11(3)
In this work, we aimed to characterize the antiviral response of an originally established porcine intestinal epithelial cell line (PIE cells) by evaluating the molecular innate immune response to rotavirus (RVs). In addition, we aimed to select immunomodulatory bacteria with antiviral capabilities. PIE cells were inoculated with RVs isolated from different host species and the infective titers and the molecular innate immune response were evaluated. In addition, the protection against RVs infection and the modulation of immune response by different lactic acid bacteria (LAB) strains was studied. The RVs strains OSU (porcine) and UK (bovine) effectively infected PIE cells. Our results also showed that RVs infection in PIE cells triggered TLR3-, RIG-I- and MDA-5-mediated immune responses with activation of IRF3 and NF-κB, induction of IFN-β and up-regulation of the interferon stimulated genes MxA and RNase L. Among the LAB strains tested, Bifidobacterium infantis MCC12 and B. breve MCC1274 significantly reduced RVs titers in infected PIE cells. The beneficial effects of both bifidobacteria were associated with reduction of A20 expression, and improvements of IRF-3 activation, IFN-β production, and MxA and RNase L expressions. These results indicate the value of PIE cells for studying RVs molecular innate immune response in pigs and for the selection of beneficial bacteria with antiviral capabilities. 相似文献
995.
996.
Diel patterns of larval drift of honmoroko Gnathopogon caerulescens in an inlet of Ibanaiko Lagoon,Lake Biwa,Japan
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Diel drift patterns of larvae of the endangered cyprinid Gnathopogon caerelescens in an inlet of the Ibanaiko Lagoon, connected to Lake Biwa in Japan, were assessed in April 2012. Peak occurrence of yolk‐sac larvae was within a few hours after dark. Drift of newly hatched larvae is considered to be an important biological mechanism that ensures larval dispersal and recruitment from the inlets (spawning grounds) to the lagoon which functions as a nursery ground. 相似文献
997.
Ninomiya K Miyamoto T Imai J Fujita N Suzuki T Iwasaki R Yagi M Watanabe S Toyama Y Suda T 《Biochemical and biophysical research communications》2007,362(2):460-466
Bone resorption by osteoclasts stimulates bone formation by osteoblasts. To isolate osteoblastic factors coupled with osteoclast activity, we performed microarray and cluster analysis of 8 tissues including bone, and found that among 10,490 genes, osteomodulin (OMD), an extracellular matrix keratan sulfate proteoglycan, was simultaneously induced with osteoclast-specific markers such as MMP9 and Acp5. OMD expression was detected in osteoblasts and upregulated during osteoblast maturation. OMD expression in osteoblasts was also detected immunohistochemically using a specific antibody against OMD. The immunoreactivity against OMD decreased in op/op mice, which lack functional macrophage colony stimulating factor (M-CSF) and are therefore defective in osteoclast formation, when compared to wild-type littermates. OMD expression in op/op mice was upregulated by M-CSF treatment. Since the M-CSF receptor c-Fms was not expressed in osteoblasts, it is likely that OMD is an osteoblast maturation marker that is induced by osteoclast activity. 相似文献
998.
Moriya S Sato S Azumaya T Suzuki O Urawa S Urano A Abe S 《Marine biotechnology (New York, N.Y.)》2007,9(2):179-191
A newly developed DNA microarray was applied to identify mitochondrial (mt) DNA haplotypes of more than 2200 chum salmon in
the Bering Sea and North Pacific Ocean in September 2002 and also 2003, when the majority of maturing fish were migrating
toward their natal river. The distribution of haplotypes occurring in Asian and North American fish in the surveyed area was
similar in the 2 years. A conditional maximum likelihood method for estimation of stock compositions indicated that the Japanese
stocks were distributed mainly in the north central Bering Sea, whereas the Russian stocks were mainly in the western Bering
Sea. The North American stocks were abundant in the North Pacific Ocean around the Aleutian Islands. These results indicate
that the Asian and North American stocks of chum salmon are nonrandomly distributed in the Bering Sea and the North Pacific
Ocean, and further the oligonuleotide DNA microarray developed by us has a high potential for identification of stocks among
mixed ocean aggregates of high-seas chum salmon. 相似文献
999.
Kawano T 《International journal of biological sciences》2007,3(1):57-63
OBJECTIVES: Studies have proposed two opposing roles for copper-bound forms of prion protein (PrP) as an anti-oxidant supporting the neuronal functions and as a pro-oxidant leading to neurodegenerative process involving the generation of reactive oxygen species. The aim of this study is to test the hypothesis in which putative copper-binding peptides derived from PrP function as possible catalysts for monoamine-dependent conversion of hydrogen peroxide to superoxide in vitro. MATERIALS AND METHODS: Four peptides corresponding to the copper (II)-binding motifs in PrP were synthesized and used for analysis of peptide-catalyzed generation of superoxide in the presence of Cu (II) and other factors naturally present in the neuronal tissues. RESULTS: Among the Cu-binding peptides tested, the amino acid sequence corresponding to the Cu-binding site in the helical region was shown to be the most active for superoxide generation in the presence of Cu(II), hydrogen peroxide and aromatic monoamines, known precursors or intermediates of neurotransmitters. Among monoamines tested, three compounds namely phenylethylamine, tyramine and benzylamine were shown to be good substrates for superoxide-generating reactions by the Cu-bound helical peptide. CONCLUSIONS: Possible roles for these reactions in development of prion disease were suggested. 相似文献
1000.
Yamamoto E Takashi T Morinaka Y Lin S Kitano H Matsuoka M Ashikari M 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2007,115(2):187-194
Reproductive barriers are important for the maintenance of species identity. We discovered a reproductive barrier via hybrid
breakdown among the progeny of a cross between the japonica rice cultivar Koshihikari and the indica rice cultivar Habataki. Genetic analysis indicated that the hybrid breakdown is regulated by the interaction of two recessive
genes: hbd2 in Habataki and hbd3 in Koshihikari. Linkage mapping showed that hbd2 is located near the 100 cM region of chromosome 2 in Habataki, whereas hbd3 is located near the 60 cM region of chromosome 11 in Koshihikari. Construction of nearly isogenic lines for hbd2 and Hbd3 (NIL-hbd2 and NIL-Hbd3), as well as a pyramiding line (NIL-hbd2 + Hbd3), confirmed that the hybrid breakdown is induced by the interaction of these two recessive genes. Our results indicate that
these genes are novel for the induction of hybrid breakdown in rice. 相似文献