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31.
32.
Tanaka M Sagawa S Hoshi J Shimoma F Matsuda I Sakoda K Sasase T Shindo M Inaba T 《Bioorganic & medicinal chemistry letters》2004,14(20):5171-5174
We report herein synthesis of PKCbeta-selective inhibitors possessing the novel pharmacophore of anilino-monoindolylmaleimide. Several compounds of this series exhibited IC50's as low as 50 nM against human PKCbeta2. One of the most potent compounds, 6l, inhibited PKCbeta1 and PKCbeta2 with IC50 of 21 and 5 nM, respectively, and exhibited selectivity of more than 60-fold in favor of PKCbeta2 relative to other PKC isozymes (PKCalpha, PKCgamma, and PKCepsilon). 相似文献
33.
Purification of alcohol dehydrogenase from bovine liver crude extract by dye-ligand affinity counter-current chromatography 总被引:2,自引:0,他引:2
Shibusawa Y Fujiwara T Shindo H Ito Y 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2004,799(2):239-244
Alcohol dehydrogenase (ADH) was extracted from a crude bovine liver homogenate by dye-ligand affinity counter-current chromatography (CCC) using a cross-axis coil planet centrifuge (x-axis CPC). The purification was performed using two types of polymer phase systems composed of 4.4% polyethylene glycol (PEG) 8000-7.0% dextran T500-0.1 M potassium phosphate buffers and 16% PEG 1000-12.5% potassium phosphate buffers, both containing a procion red dye as an affinity ligand at various pH values. The best purification was achieved using the PEG 1000-potassium phosphate system at pH 7.3 containing 0.05% procion red as a ligand. The upper PEG-rich phase containing procion red was used as the stationary phase and a crude bovine liver homogenate was eluted with the potassium phosphate-rich lower phase at 0.5 ml/min. After elution of bovine liver proteins in the homogenate, ADH still retained in the stationary phase was collected from the column by eluting with the PEG 1000-rich upper phase. Collected fractions were analyzed by ADH enzymatic activity and by sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis (PAGE) to detect contaminant proteins in the ADH fractions. The ADH was purified directly from crude bovine liver extract within 6h with minimum loss of its enzymatic activity. 相似文献
34.
Murakami K Irie K Morimoto A Ohigashi H Shindo M Nagao M Shimizu T Shirasawa T 《The Journal of biological chemistry》2003,278(46):46179-46187
Cerebral amyloid angiopathy (CAA) due to beta-amyloid (Abeta) is one of the specific pathological features of familial Alzheimer's disease. Abeta mainly consisting of 40- and 42-mer peptides (Abeta40 and Abeta42) exhibits neurotoxicity and aggregative abilities. All of the variants of Abeta40 and Abeta42 found in CAA were synthesized in a highly pure form and examined for neurotoxicity in PC12 cells and aggregative ability. All of the Abeta40 mutants at positions 22 and 23 showed stronger neurotoxicity than wild-type Abeta40. Similar tendency was observed for Abeta42 mutants at positions 22 and 23 whose neurotoxicity was 50-200 times stronger than that of the corresponding Abeta40 mutants, suggesting that these Abeta42 mutants are mainly involved in the pathogenesis of CAA. Although the aggregation of E22G-Abeta42 and D23N-Abeta42 was similar to that of wild-type Abeta42, E22Q-Abeta42 and E22K-Abeta42 aggregated extensively, supporting the clinical evidence that Dutch and Italian patients are diagnosed as hereditary cerebral hemorrhage with amyloidosis. In contrast, A21G mutation needs alternative explanation with the exception of physicochemical properties of Abeta mutants. Attenuated total reflection-Fourier transform infrared spectroscopy spectra suggested that beta-sheet content of the Abeta mutants correlates with their aggregation. However, beta-turn is also a critical secondary structure because residues at positions 22 and 23 that preferably form two-residue beta-turn significantly enhanced the aggregative ability. 相似文献
35.
Osteogenic differentiation of the mesenchymal progenitor cells, Kusa is suppressed by Notch signaling 总被引:6,自引:0,他引:6
Shindo K Kawashima N Sakamoto K Yamaguchi A Umezawa A Takagi M Katsube K Suda H 《Experimental cell research》2003,290(2):370-380
Notch receptor plays a crucial role in proliferation and differentiation of many cell types. To elucidate the function of Notch signaling in osteogenesis, we transfected the constitutively active Notch1 (Notch intracellular domain, NICD) into two different osteoblastic mesenchymal cell lines, KusaA and KusaO, and examined the changes of their osteogenic potentials. In NICD stable transformants (KusaA(NICD) and KusaO(NICD)), osteogenic properties including alkaline phosphatase activity, expression of osteocalcin and type I collagen, and in vitro calcification were suppressed. Transient transfection of NICD attenuated the promoter activities of Cbfa1 and Ose2 element. KusaA was capable of forming trabecular bone-like tissues when injected into mouse abdomen, but this in vivo bone forming activity was significantly suppressed in KusaA(NICD). Osteoclasts were induced in the KusaA-derived bone-like tissues, but lacked in the KusaA(NICD)-derived tissues. These results suggest that Notch signaling suppresses the osteoblastic differentiation of mesenchymal progenitor cells. 相似文献
36.
A consensus linkage map for sugi (Cryptomeria japonica) from two pedigrees, based on microsatellites and expressed sequence tags 总被引:3,自引:0,他引:3
Tani N Takahashi T Iwata H Mukai Y Ujino-Ihara T Matsumoto A Yoshimura K Yoshimaru H Murai M Nagasaka K Tsumura Y 《Genetics》2003,165(3):1551-1568
A consensus map for sugi (Cryptomeria japonica) was constructed by integrating linkage data from two unrelated third-generation pedigrees, one derived from a full-sib cross and the other by self-pollination of F1 individuals. The progeny segregation data of the first pedigree were derived from cleaved amplified polymorphic sequences, microsatellites, restriction fragment length polymorphisms, and single nucleotide polymorphisms. The data of the second pedigree were derived from cleaved amplified polymorphic sequences, isozyme markers, morphological traits, random amplified polymorphic DNA markers, and restriction fragment length polymorphisms. Linkage analyses were done for the first pedigree with JoinMap 3.0, using its parameter set for progeny derived by cross-pollination, and for the second pedigree with the parameter set for progeny derived from selfing of F1 individuals. The 11 chromosomes of C. japonica are represented in the consensus map. A total of 438 markers were assigned to 11 large linkage groups, 1 small linkage group, and 1 nonintegrated linkage group from the second pedigree; their total length was 1372.2 cM. On average, the consensus map showed 1 marker every 3.0 cM. PCR-based codominant DNA markers such as cleaved amplified polymorphic sequences and microsatellite markers were distributed in all linkage groups and occupied about half of mapped loci. These markers are very useful for integration of different linkage maps, QTL mapping, and comparative mapping for evolutional study, especially for species with a large genome size such as conifers. 相似文献
37.
Shindo C Sasakuma T 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2002,104(6-7):1003-1010
Genotype-specific gene expression in response to vernalization in common wheat was examined by the differential display method. Two near-isogenic lines of Vrn-A1 ( Vrn-A1 for the spring type and vrn-A1 for the winter type) were treated by vernalization of developing embryos in detached-ear cultures. This treatment was effective to promote vrn-A1 genotypes to head at a time equivalent to that of Vrn-A1. Differential cDNA fragments were isolated by the RT-PCR method from embryos subjected to vernalization treatments for 2- and 4-weeks at DAP10 and DAP20 stages, respectively. Among 110 differential cDNA fragments isolated, 48 were examined for their chromosomal locations and designated as wec ( wheat- embryo cold treatment) genes. Seven wec genes showed genotype-specific expression in response to vernalization. The statistical analysis utilizing two recombinant inbred lines showed that four wec genes were significantly associated with heading factors. 相似文献
38.
Causal relationship between the loss of RUNX3 expression and gastric cancer 总被引:137,自引:0,他引:137
Li QL Ito K Sakakura C Fukamachi H Inoue Ki Chi XZ Lee KY Nomura S Lee CW Han SB Kim HM Kim WJ Yamamoto H Yamashita N Yano T Ikeda T Itohara S Inazawa J Abe T Hagiwara A Yamagishi H Ooe A Kaneda A Sugimura T Ushijima T Bae SC Ito Y 《Cell》2002,109(1):113-124
Runx3/Pebp2alphaC null mouse gastric mucosa exhibits hyperplasias due to stimulated proliferation and suppressed apoptosis in epithelial cells, and the cells are resistant to growth-inhibitory and apoptosis-inducing action of TGF-beta, indicating that Runx3 is a major growth regulator of gastric epithelial cells. Between 45% and 60% of human gastric cancer cells do not significantly express RUNX3 due to hemizygous deletion and hypermethylation of the RUNX3 promoter region. Tumorigenicity of human gastric cancer cell lines in nude mice was inversely related to their level of RUNX3 expression, and a mutation (R122C) occurring within the conserved Runt domain abolished the tumor-suppressive effect of RUNX3, suggesting that a lack of RUNX3 function is causally related to the genesis and progression of human gastric cancer. 相似文献
39.
Essential role of the adhesion receptor LFA-1 for T cell-dependent fulminant hepatitis 总被引:6,自引:0,他引:6
Matsumoto G Tsunematsu S Tsukinoki K Ohmi Y Iwamiya M Oliveira-dos-Santos A Tone D Shindo J Penninger JM 《Journal of immunology (Baltimore, Md. : 1950)》2002,169(12):7087-7096
Viral hepatitis affects more than 2 billion people worldwide. In particular, no effective treatment exists to abrogate death and liver damage in fulminant hepatitis. Activation of T cells is an initial and critical event in the pathogenesis of liver damage in autoimmune and viral hepatitis. The precise molecular mechanisms that induce T cell-mediated hepatocyte injury remain largely unclear. In mice, T cell-dependent hepatitis and acute liver damage can be modeled using ConA. In this study, we examined the role of the adhesion receptor LFA-1 in ConA-induced acute hepatic damage using LFA-1(-/-) (CD11a) mice. Massive liver cell apoptosis and metabolic liver damage were observed in LFA-1(+/+) mice following ConA injection. By contrast, LFA-1(-/-) mice were completely resistant to ConA-induced hepatitis and none of the LFA-1(-/-) mice showed any hepatic damage. Whereas activated hepatic T cells remained in the liver in LFA-1(+/+) mice, activated T cells were rapidly cleared from the livers of LFA-1(-/-) mice. Mechanistically, T cells from LFA-1(-/-) mice showed markedly reduced cytotoxicity toward liver cells as a result of impaired, activation-dependent adhesion. Importantly, adoptive transfer of hepatic T cells from LFA-1(+/+) mice, but not from LFA-1(-/-) mice, sensitized LFA-1(-/-) mice to ConA-induced hepatitis. Thus, LFA-1 expression on T cells is necessary and sufficient for T cell-mediated liver damage in vivo. These results provide the first genetic evidence on an adhesion receptor, LFA-1, that has a crucial role in fulminant hepatitis. These genetic data identify LFA-1 as a potential key target for the treatment of T cell-mediated hepatitis and the prevention of liver damage. 相似文献
40.
Takao M Yamaguchi A Yoshikawa K Terashita T Sakai T 《Bioscience, biotechnology, and biochemistry》2002,66(2):430-433
The gene that encodes a thermostable endo-arabinase (called ABN-TS) from Bacillus thermodenitrificans TS-3 was cloned, sequenced, and expressed in the mesophilic B. subtilis. The gene contained an open reading frame consists of 939 bp, which encodes 313 amino acids. The deduced amino acid sequence of the enzyme showed 50, 46, and 36% similarity with endo-arabinase from B. subtilis IFO 3134 (PPase-C), Pseudomonas fluorescens (ArbA), and Aspergillus niger (ABNA), respectively. The hydrophobic and acidic amino acids making up ABN-TS outnumbered those in PPase-C. The gene product expressed in B. subtilis, as the host, had substantially the same characteristics, and was stable up to 70 degrees C, and the reaction was optimal around 70 degrees C, as well as native ABN-TS. 相似文献