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111.
Uchida H Fujitani K Kawai Y Kitazawa H Horii A Shiiba K Saito K Saito T 《Bioscience, biotechnology, and biochemistry》2004,68(5):1004-1010
A new binding assay to investigate the mechanism of adhesion of lactic acid bacteria to the human intestine was established by the surface plasmon resonance technique using a biosensor BIACORE1000. Cells of 26 strains of the Lactobacillus acidophilus group as analytes were eluted onto a sensor chip on which were immobilized biotinylated A-trisaccharide polymer probes having human A-type antigen [(GalNAcalpha1-3(Fucalpha1-2)Gal)-] or human colonic mucin of blood type A (HCM-A) as ligands. In the first screening, high adhesive affinity to the A-trisaccharide BP-probe was observed in L. acidophilus OLL2769, L. crispatus JCM8778, LA205 and LA206. In the second screening, which used HCM-A, only L. acidophilus OLL2769 and L. crispatus JCM8778 were selected as adhesive strains with specific binding ability to human A-antigen. The results indicated that some strains of the L. acidophilus group could recognize and bind the sugar chain of A-antigen structure on HCM. 相似文献
112.
Abe M Ozawa Y Uda Y Yamada F Morimitsu Y Nakamura Y Osawa T 《Bioscience, biotechnology, and biochemistry》2004,68(7):1601-1604
The antimicrobial activities of the three diterpene dialdehydes, miogadial, galanal A and galanal B, isolated from flower buds of the myoga (Zingiber mioga Roscoe) plant were investigated with some strains of bacteria, yeasts and molds. Among the three compounds, miogadial exhibited relatively greater antimicrobial activity than the others against Gram-positive bacteria and yeasts. Galanals A and B also behaved as antimicrobial agents against Gram-positive bacteria and yeasts. The content of miogadial in the flower buds was much higher than that in the leaves, whereas galanals A and B were contained at high levels in the leaves and rhizomes. 相似文献
113.
Park AM Chou CC Drury PC Okuyama Y Peter A Hamabe A Miyauchi Y Kass RM Karagueuzian HS Fishbein MC Lin SF Chen PS 《American journal of physiology. Heart and circulatory physiology》2004,286(6):H2072-H2077
The thoracic vein hypothesis of chronic atrial fibrillation (AF) posits that rapid, repetitive activations from muscle sleeves within thoracic veins underlie the mechanism of sustained AF. If this is so, thoracic vein ablation should terminate sustained AF and prevent its reinduction. Six female mongrel dogs underwent chronic pulmonary vein (PV) pacing at 20 Hz to induce sustained (>48 h) AF. Bipolar electrodes were used to record from the atria and thoracic veins, including the vein of Marshall, four PVs, and the superior vena cava. Radio frequency (RF) application was applied around the PVs and superior vena cava and along the vein of Marshall until electrical activity was eliminated. Computerized mapping (1,792 electrodes, 1 mm resolution) was also performed. Sustained AF was induced in 30.6 +/- 6.5 days, and ablation was done 17.3 +/- 8.5 days afterward. Before ablation, the PVs had shorter activation cycle lengths than the atria, and rapid, repetitive activations were observed in the PVs. All dogs converted to sinus rhythm during (n = 4 dogs) or within 90 min of completion of RF ablation. Rapid atrial pacing afterward induced only nonsustained (<60 s) AF in all dogs. Average AF cycle lengths after reinduction were significantly (P = 0.01) longer (183 +/- 31.5 ms) than baseline (106 +/- 16.2 ms). There were no activation cycle length gradients after RF application. We conclude that thoracic vein ablation converts canine sustained AF into sinus rhythm and prevents the reinduction of sustained AF. These findings suggest that thoracic veins are important in the maintenance of AF in dogs. 相似文献
114.
Taurine inhibits apoptosis by preventing formation of the Apaf-1/caspase-9 apoptosome 总被引:5,自引:0,他引:5
Takatani T Takahashi K Uozumi Y Shikata E Yamamoto Y Ito T Matsuda T Schaffer SW Fujio Y Azuma J 《American journal of physiology. Cell physiology》2004,287(4):C949-C953
Cardiomyocyte apoptosis contributes to cell death during myocardial infarction. One of the factors that regulate the degree of apoptosis during ischemia is the amino acid taurine. To study the mechanism underlying the beneficial effect of taurine, we examined the interaction between taurine and mitochondria-mediated apoptosis using a simulated ischemia model with cultured rat neonatal cardiomyocytes sealed in closed flasks. Exposure to medium containing 20 mM taurine reduced the degree of apoptosis following periods of ischemia varying from 24 to 72 h. In the untreated group, simulated ischemia for 24 h led to mitochondrial depolarization accompanied by cytochrome c release. The apoptotic cascade was also activated, as evidenced by the activation of caspase-9 and -3. Taurine treatment had no effect on mitochondrial membrane potential and cytochrome c release; however, it inhibited ischemia-induced cleavage of caspase-9 and -3. Taurine loading also suppressed the formation of the Apaf-1/caspase-9 apoptosome and the interaction of caspase-9 with Apaf-1. These findings demonstrate that taurine effectively prevents myocardial ischemia-induced apoptosis by inhibiting the assembly of the Apaf-1/caspase-9 apoptosome. ischemia; cultured cardiomyocytes 相似文献
115.
Although methods for reverse genetics of herpesviruses have been established in early 1980s, the steps are laborious and time-consuming. In 1997, Dr. Koszinwski's group reported a novel approach for the construction of herpesvirus mutants, based on cloning the viral genome as a bacterial artificial chromosome (BAC) in E. coli. This technique allows the maintenance of viral genomes as plasmid in E. coli and the reconstitution of viral progeny by transfection of the BAC plasmid into eukaryotic cells. Any genetics modification of the viral genome in E. coli using bacterial genetics is possible, thereby facilitating the introduction of mutagenesis into herpesvirus genome. This 'BAC system' has opened new avenues for reverse and forward genetics of herpesviruses in basic research and in vector development for human therapy. Here we describe the principle of the 'BAC system' in herpesvirus researches. 相似文献
116.
4-Acylamino-6-arylfuro[2,3-d]pyrimidines: potent and selective glycogen synthase kinase-3 inhibitors
Maeda Y Nakano M Sato H Miyazaki Y Schweiker SL Smith JL Truesdale AT 《Bioorganic & medicinal chemistry letters》2004,14(15):3907-3911
Modeling studies of a furo[2,3-d]pyrimidine GSK-3 hit compound 1 superimposed onto the X-ray crystal structure of a legacy pyrazolo[3,4-c]pyridazine GSK-3 inhibitor 2 led to the identification of 4-acylamino-6-arylfuro[2,3-d]pyrimidine template 3. Synthesis of analogues based on template 3 has resulted in a number of potent and selective GSK-3beta inhibitors. The most potent and selective compound was the m-pyridyl analogue 24. 相似文献
117.
Plastid protein import 2 (ppi2), a mutant of Arabidopsis thaliana, lacks a homologue of a component of the translocon at the outer envelope membrane of chloroplasts (Toc), designated Toc159 of the pea. Toc159 is thought to be essential for the import of photosynthetic proteins into chloroplasts. In order to investigate the effect of protein import on the plant development, we examined the morphologies of the developing leaves and the shoot apical meristems (SAM) in the ppi2 plants. Our histological analysis revealed that the development of leaves is severely affected in ppi2, while the structure of SAM is normal. Abnormalities in leaves became obvious in the later stages of leaf development, resulting in the generation of mature leaves with fewer mesophyll cells and more intercellular spaces as compared with the wild type. Palisade and spongy tissues of the mature leaves were indistinguishable in ppi2. Replication of chloroplast DNA was also suggested to be impaired in ppi2. Our results suggest that protein import into chloroplasts is important for the normal development of leaves. 相似文献
118.
Saeki Y Isono E Oguchi T Shimada M Sone T Kawahara H Yokosawa H Toh-e A 《Genes & genetic systems》2004,79(2):77-86
We constructed polyubiquitin derivatives that contain a tandem repeat of ubiquitins and were insensitive to ubiquitin hydrolases. They were designated tandem ubiquitin (tUb) with the number of repeats, such as tUb2. When tUbs were expressed under the control of the GAL1 promoter in the wild-type yeast strain, growth was strongly inhibited. Under these conditions, the degradation of N-end rule substrates, a UFD substrate and Gcn4 was inhibited, indicating that the tUb inhibits 26S proteasome activity. Consistent with this, tUb binds to the 26S proteasome. We showed that tUb inhibited the in vitro degradation of polyubiquitinylated Sic1 by the 26S proteasome. When tUB6 messenger RNA was injected into Xenopus embryos, cell division was inhibited, suggesting that tUb can be used as a versatile inhibitor of the 26S proteasome. 相似文献
119.
Akahoshi M Nakashima H Miyake K Inoue Y Shimizu S Tanaka Y Okada K Otsuka T Harada M 《Human genetics》2003,112(3):237-243
Host genetic factors may be important determinants of susceptibility to tuberculosis, and several candidate gene polymorphisms have been shown to date. A series of recent reports concerning rare human deficiencies in the type-1 cytokine pathway suggest that more subtle variants of relevant genes may also contribute to susceptibility to tuberculosis at the general population level. To investigate whether polymorphisms in the interleukin-12 receptor (IL-12R) gene predispose individuals to tuberculosis, we studied these genes by single-strand conformational polymorphism analysis and direct sequencing. Although no common polymorphisms could be identified in the IL-12R beta 2 gene ( IL-12RB2), we confirmed four single nucleotide polymorphisms (SNPs; 641A-->G, 684C-->T, 1094T-->C, and 1132G-->C) causing three missense variants (Q214R, M365T, G378R) and one synonymous substitution in the extracellular domain of the IL-12R beta 1 gene ( IL12RB1). All SNPs were in almost perfect linkage disequilibrium (D'=0.98), and two common haplotypes of IL12RB1(allele 1: Q214-M365-G378; allele 2: R214-T365-R378) were revealed. Polymerase chain reaction/restriction fragment length polymorphism and sequence analyses were used to type IL12RB1polymorphisms in 98 patients with tuberculosis and 197 healthy controls in Japanese populations. In our case-control association study of tuberculosis, the R214-T365-R378 allele (allele 2) was over-represented in patients with tuberculosis, and homozygosity for R214-T365-R378 (the 2/2 genotype) was significantly associated with tuberculosis (odds ratio: 2.45; 95% CI: 1.20-4.99; P=0.013). In healthy subjects, homozygotes for R214-T365-R378 had lower levels of IL-12-induced signaling, according to differences in cellular responses to IL-12 between two haplotypes. These data suggest that the R214-T365-R378 allele, i.e., variation in IL12RB1, contribute to tuberculosis susceptibility in the Japanese population. This genetic variation may predispose individuals to tuberculosis infection by diminishing receptor responsiveness to IL-12 and to IL-23, leading to partial dysfunction of interferon-gamma-mediated immunity. 相似文献
120.
Ando Y Liang Y Ishigaki S Niwa J Jiang Y Kobayashi Y Yamamoto M Doyu M Sobue G 《Neurochemical research》2003,28(6):839-846
Amyotrophic lateral sclerosis is characterized by selective motor neuron degeneration. An apoptotic pathway is thought to be involved. It is difficult, however, to analyze the molecular pathogenic mechanism in single motor neurons because of complexity in the neural tissue, which consists of multiple lineages of cells neighboring motor neurons. We quantified the caspase-1 and -3 mRNA in single motor neurons and neighboring glial cells isolated from the spinal ventral horn of mutant SOD1 transgenic (Tg) mice and littermates. Motor neurons and neighboring glial cells were isolated from spinal sections by laser microdissection, and the mRNAs were quantified by RT-PCR. In the Tg mice, caspase-1 mRNA was first upregulated in motor neurons and second in glial cells. The caspase-3 mRNA was increased in motor neurons following the caspase-1 mRNA. These results indicated that caspase-1 and -3 mRNAs are differentially upregulated in motor neurons and glial cells of the Tg mice, and that mRNAs in isolated cells can be accurately assessed using our procedures. 相似文献