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101.
Suzuki Y Asano K Shiraishi Y Oguma T Shiomi T Fukunaga K Nakajima T Niimi K Yamaguchi K Ishizaka A 《Prostaglandins, leukotrienes, and essential fatty acids》2004,71(6):375-382
Thromboxane A2 receptor (TP) mediates bronchial smooth muscle cell (BSMC) contraction, airway hyperresponsiveness, and airway inflammation in patients with asthma. In the present study, a pathogenic role of TP activation in airway remodeling was examined using primary cultures of human BSMC. A TP agonist, I-BOP, concentration-dependently enhanced not only bromodeoxyuridine (BrdU) uptake but also cell proliferation of BSMC. A TP-selective antagonist, AA-2414, blocked the effects of I-BOP on both BrdU uptake and cell proliferation. I-BOP-induced BrdU uptake was significantly blocked by two non-selective tyrosine kinase inhibitors, genistein and herbimycin A, or a Src family tyrosine kinase inhibitor, PP2, but not by an inhibitor of epidermal growth factor (EGF) receptor-associated tyrosine kinase, AG1478. In conclusion, TP receptor activation causes DNA synthesis and cell proliferation of human BSMC by activating tyrosine kinases including Src, but not by EGF receptor transactivation. 相似文献
102.
Identification of cold-inducible downstream genes of the Arabidopsis DREB1A/CBF3 transcriptional factor using two microarray systems 总被引:20,自引:0,他引:20
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Oku Y Ohtaki A Kamitori S Nakamura N Yohda M Ohno H Kawarabayasi Y 《Journal of inorganic biochemistry》2004,98(7):1194-1199
Cytochrome P450 from thermoacidophilic crenarchaeon, Sulfolobus tokodaii strain 7 (P450st) has been expressed in Escherichia coli and purified at high homogeneity. P450st was crystallized in an orthorhombic system with the space group P2(1)2(1)2(1) and cell dimensions of a=53.6 A, b=55.1 A, and c=130.9 A, and the structure was determined at a 3.0 A resolution. The final R-factor was 0.194 (Rfree=0.235). Structural comparison with cytochrome P450 from S. solfataricus (CYP119) suggests that the region composed of the F to G helices and the Cl- binding site is responsible for the affinity for a ligand coordinating heme iron. Direct electrochemistry of P450st in a didodecyldimethylammonium bromide (DDAB) film on a plastic formed carbon (PFC) electrode has also been demonstrated. A quasi-reversible redox response has been observed even at elevated temperatures of up to 80 degrees C. 相似文献
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Jose B Oniki Y Kato T Nishino N Sumida Y Yoshida M 《Bioorganic & medicinal chemistry letters》2004,14(21):5343-5346
Cyclic tetrapeptides containing trifluoromethyl and pentafluoroethyl ketone as zinc binding functional group were synthesized as potent HDAC inhibitors. Evaluation by human HDAC inhibition assay and p21 promoter assay showed that these inhibitors are promising anticancer agents. 相似文献
108.
Yusuke?YamanoueEmail author Masaki?Miya Keiichi?Matsuura Masaya?Katoh Harumi?Sakai Mutsumi?Nishida 《Ichthyological Research》2004,51(3):269-273
We determined the complete nucleotide sequences of the mitochondrial genomes for the three currently recognized species of ocean sunfish: Mola mola, Masturus lanceolatus, and Ranzania laevis (Tetraodontiformes: Molidae). Each genome contained the 37 genes as found in teleosts, with the typical gene order in teleosts. Bayesian, maximum-likelihood, and maximum-parsimony analyses were conducted with the data set comprising concatenated nucleotide sequences from 36 genes (excluding the ND6 gene) of three molids and four outgroups (three tetraodontiforms plus a caproid). The resultant trees supported monophyly of the Molidae and its intrarelationships ((Mola, Masturus), Ranzania), which were congruent with previous morphology-based hypotheses. 相似文献
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Koji?HattoriEmail author Ken?Ikeuchi Yusuke?Morita Yoshinori?Takakura 《Arthritis research & therapy》2004,7(1):R38
Osteoarthritis (OA) is one of the most prevalent chronic conditions. The histological cartilage changes in OA include surface
erosion and irregularities, deep fissures, and alterations in the staining of the matrix. The reversibility of these chondral
alterations is still under debate. It is expected that clinical and basic science studies will provide the clinician with
new scientific information about the natural history and optimal treatment of OA at an early stage. However, a reliable method
for detecting microscopic changes in early OA has not yet been established. We have developed a novel system for evaluating
articular cartilage, in which the acoustic properties of the articular cartilage are measured by introducing an ultrasonic
probe into the knee joint under arthroscopy. The purpose of this study was to assess microscopic cartilage damage in OA by
using this cartilage evaluation system on collagenase-treated articular cartilage in vivo and in vitro. Ultrasonic echoes from articular cartilage were converted into a wavelet map by wavelet transformation. On the wavelet map,
the maximum magnitude and echo duration were selected as quantitative indices. Using these indices, the articular cartilage
was examined to elucidate the relationships of the ultrasonic analysis with biochemical, biomechanical and histological analyses.
In the in vitro study, the maximum magnitude decreased as the duration of collagenase digestion increased. Correlations were observed between
the maximum magnitude and the proteoglycan content from biochemical findings, and the maximum magnitude and the aggregate
modulus from biomechanical findings. From the histological findings, matrix staining of the surface layer to a depth of 500
μm was closely related to the maximum magnitude. In the in vivo study, the maximum magnitude decreased with increasing duration of the collagenase injection. There was a significant correlation
between the maximum magnitude and the aggregate modulus. The evaluation system therefore successfully detected microscopic
changes in degenerated cartilage with the use of collagen-induced OA. 相似文献