排序方式: 共有177条查询结果,搜索用时 375 毫秒
91.
Iain J. Day Kiminori Maeda Howard J. Paisley K. Hun Mok P. J. Hore 《Journal of biomolecular NMR》2009,44(2):77-86
Photo-CIDNP NMR spectroscopy is a powerful method for investigating the solvent accessibility of histidine, tyrosine and tryptophan
residues in a protein. When coupled to real-time NMR, this technique allows changes in the environments of these residues
to be used as a probe of protein folding. In this paper we describe experiments performed to monitor the refolding of ribonuclease
A following dilution from a high concentration of chemical denaturant. These experiments provide a good example of the utility
of this technique which provides information that is difficult to obtain by other biophysical methods. Real-time photo-CIDNP
measurements yield residue-specific kinetic data pertaining to the folding reaction, interpreted in terms of current knowledge
of the folding of bovine pancreatic ribonuclease A. 相似文献
92.
Kunihiro Kishida Mihoko Tominaga Kiminori Matsubara Masanori Taguchi Masanori Noguchi Noriaki Tsunawake Yoshihiro Shidoji 《PloS one》2009,4(11)
The mitochondrial (mt) DNA C5178A and A10398G polymorphisms have been reported to be associated with mental disorders such as bipolar disorder. However, the effects of these polymorphisms on temperament in healthy people are poorly understood. Evaluating healthy subjects can have the advantage of providing new strategies for maintaining psychological health and preventing mental illness. We examined the association between mtDNA polymorphisms and temperament in Japanese students. There was no significant difference in examined temperament when analysed by genotypes, 5178–10398 haplotypes, or sex. The subgroup analysis based on sex indicated that there was an interactive effect of the mtDNA A10398G polymorphism and sex on anxiety and obsession. This finding is preliminary and cannot exclude the possibility of false-positive due to small sample size (144 subjects) and multiple statistical testing. Further studies involving a larger sample size or other ethnic groups are necessary to confirm that mtDNA A10398G polymorphism can be a genetic factor for temperament. 相似文献
93.
Akiyama T Sadahira Y Matsubara K Mori M Igarashi Y 《Journal of molecular histology》2008,39(5):527-533
Sphingosine-1-phosphate receptor 1 (S1P1), a receptor for sphingosine-1-phosphate, has been shown to play an important role in the migration, proliferation, and survival
of several types of cell including endothelial cells. Given that S1P1 signaling could serve as a therapeutic target, we evaluate the expression of S1P1 in formalin-fixed and paraffin-embedded sections from human tissues, using automated immunostainers (Ventana). The specificity
of the polyclonal rabbit anti-human S1P1 antibody used in this study was defined by immunostaining of the vasculature in S1P
1
−/−
and S1P
1
+/−
mouse embryos. The antibody stained the newly formed vasculatures ex vivo in a serum-free matrix culture model using rat
aortic rings. In human specimens, S1P1 was strongly expressed on the cell surface membrane of endothelial cells of blood and lymphatic vessels in all tissues examined.
The expression of S1P1 was confirmed by the flow cytometric analysis and real time RT-PCR of an angiosarcoma cell line. This study indicates that
S1P1 can be used as an immunohistochemical marker for human tissue endothelial cells. 相似文献
94.
95.
Awaya T Yokosaki Y Yamane K Usui H Kohno N Eboshida A 《Obesity (Silver Spring, Md.)》2008,16(6):1463-1466
Mice lacking the integrin alphaMbeta2 (Mac-1, CD11b/CD18) develop an obese phenotype on western diet rich in fat. However, no association has been found between variations in the human genes encoding the integrin alphaMbeta2 and obesity. This study was aimed to investigate the association between a single-nucleotide polymorphism (SNP) (rs235326) in the gene encoding human integrin beta2 subunit (ITGB2) with obesity. Our subject cohort comprised 651 people of Japanese ethnicity, of which 274 were Japanese Americans living in Hawaii, and the remaining 377 were native Japanese, two populations in the same genetic background with or without westernized life style. We genotyped the rs235326 polymorphism using a TaqMan assay. In the Japanese-American population, the risk of obesity was found to be 3.29-fold higher (a 95% confidence interval of 1.25-8.67, P = 0.02) in TT homozygotes than in C carriers, using a recessive model and logistic regression analysis that had been adjusted for age. This association was not found in native Japanese individuals. These results indicate that the rs235326 polymorphism in the ITGB2 gene is associated with obesity in Japanese living in the United States whose diet has become "westernized." 相似文献
96.
Novel diphenylamine-type estrogen receptor ligands were designed and synthesized, and their biological activities were evaluated by means of binding assays for estrogen receptor-alpha and -beta and cell proliferation assay using MCF-7 cells. Compounds 4f, 11b, 12c, and 8 showed moderate estrogenic activities. We propose that the diphenylamine skeleton may be a privileged structure for various nuclear receptor ligands, including RAR, RXR, and AR ligands. 相似文献
97.
98.
Mizushina Y Xu X Matsubara K Murakami C Kuriyama I Oshige M Takemura M Kato N Yoshida H Sakaguchi K 《Biochemical and biophysical research communications》2003,312(4):1025-1032
Vitamin B(6) compounds such as pyridoxal 5(')-phosphate (PLP), pyridoxal (PL), pyridoxine (PN), and pyridoxamine (PM), which reportedly have anti-angiogenic and anti-cancer effects, were thought to be inhibitors of some types of eukaryotic DNA polymerases. PL moderately inhibited only the activities of calf DNA polymerase alpha (pol alpha), while PN and PM had no inhibitory effects on any of the polymerases tested. On the other hand, PLP, a phosphated form of PL, was potentially a strong inhibitor of pol alpha and epsilon from phylogenetic-wide organisms including mammals, fish, insects, plants, and protists. PLP did not suppress the activities of prokaryotic DNA polymerases such as Escherichia coli DNA polymerase I and Taq DNA polymerase, or DNA-metabolic enzymes such as deoxyribonuclease I. For pol alpha and epsilon, PLP acted non-competitively with the DNA template-primer and competitively with the nucleotide substrate. Since PL was converted to PLP in vivo after being incorporated into human cancer cells, the anti-angiogenic and anti-cancer effects caused by PL must have been caused by the inhibition of pol alpha and epsilon activities after conversion to PLP. 相似文献
99.
Maeda K Lyon CE Lopez JJ Cemazar M Dobson CM Hore PJ 《Journal of biomolecular NMR》2000,16(3):235-244
Two new techniques offering considerable improvements in the quality of 1H photo-CIDNP spectra of proteins are demonstrated. Both focus on the problem of progressive photo-degradation of the flavin dye used to generate polarization in exposed tryptophan, tyrosine and histidine side-chains. One approach uses rapid addition and removal of protein/flavin solution between light flashes to mix the NMR sample and introduce fresh dye into the laser-irradiated region. The other involves chemical oxidation of photo-reduced flavin by the addition of hydrogen peroxide. In both cases a larger number of scans can be accumulated before the flavin is exhausted than would otherwise be possible. The techniques are demonstrated by 600 MHz CIDNP-NOESY spectroscopy of bovine holo--lactalbumin, and by real-time CIDNP observation of the refolding of bovine apo--lactalbumin following rapid dilution from a high concentration of chemical denaturant. 相似文献
100.
Ukitsu H Kuromori T Toyooka K Goto Y Matsuoka K Sakuradani E Shimizu S Kamiya A Imura Y Yuguchi M Wada T Hirayama T Shinozaki K 《Plant & cell physiology》2007,48(11):1524-1533
In transposon-tagged lines of Arabidopsis we found two new mutants, cof1-1 and cof1-2 (cuticular defect and organ fusion), that show the phenotype of wilting when grown in soil, organ fusion of rosette leaves and infertility. Toluidine blue testing and scanning electron microscopy observation revealed that these mutants had cuticular defects in the stems and adult leaves, but not in cotyledones. Transmission electron microscopy observation revealed thinner cuticle layers in the mutants, and cuticular materials interspersed between the two fused epidermal layers were observed in the mutant rosette leaves. These two mutants had a transposon insertion in the coding regions of WBC11, which was classified as a member of ABC transporter genes in Arabidopsis. WBC11 showed high sequence similarity to CER5 (also called WBC12), which was involved in cuticular lipid export. Gas chromatographic analysis revealed that C29 alkane extracted from the stem surface of cof1 mutants was reduced whereas C29 ketone was accumulated, which was different from the case of cer5 mutants. While cer5 mutants had fairly normal morphology, cof1 mutants had pleiotropic phenotypes so that COF1/WBC11 could have important roles different from those of CER5/WBC12. We also found that C29 alkane was accumulated in the intracellular extract of cof1 mutants, suggesting a function for WBC11 in the direct transport of lipid molecules. Pollen observation showed that mutant pollen grains were irregularly shaped. The function of COF1/WBC11 in lipid transport for the construction of cuticle layers and pollen coats for normal organ formation is discussed. 相似文献