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101.
102.
Ikuta K Yamada T Shimomura T Kuratsune H Kawahara R Ikawa S Ohnishi E Sokawa Y Fukushi H Hirai K Watanabe Y Kurata T Kitani T Sairenji T 《Microbes and infection / Institut Pasteur》2003,5(12):1096-1102
To investigate the association of viral infections with chronic fatigue syndrome (CFS), we assayed 2', 5'-oligoadenylate synthetase (2-5AS) activities in peripheral blood mononuclear cells from CFS patients in Japan. These patients were diagnosed in two hospitals, H1 and H2, located in different areas of the country. The activities were detected in 19 (86%) and 7 (32%) of each of the 22 patients in H1 and H2, respectively, while they were detected in only four (11%) out of the 38 healthy controls. IFN-alpha was similarly detected in a few CFS patients and healthy controls. We also assayed the antibody titers against Epstein-Barr virus (EBV) and Coxiella burnetii in these patients. The EBV anti-EA-IgG antibodies were detected in two (9%) and seven (32%) of each of the 22 patients in H1 and H2, respectively. Anti-C. burnetii IgG antibodies were detected in six (27%) out of 22 patients in H1 but not in 22 patients in H2, while they were detected in one (11%) of the nine healthy controls. Some CFS patients may be associated with EBV or C. burnetii infection. There were some statistical correlations between the 2-5AS activities and antibody titers of EA-IgG (P < 0.05, Student's t-test) but not to the antibody titers of C. burnetii. The up-regulation of 2-5AS activities suggests immunological dysfunctions with some virus infections in the CFS patients. Our results indicate that 2-5AS activities are useful for a diagnostic marker of CFS and for exploring the complicated pathogenesis of CFS. 相似文献
103.
Recent studies have suggested that mitochondrial aldehyde dehydrogenase (aldehyde:NAD(P)(+) oxidoreductase, EC 1.2.1.3) (ALDH2) plays essential roles in pollen development in plants. Rice (Oryza sativa L.) ALDH2 is encoded by at least two ALDH2 genes, one of which (ALDH2a) was previously identified. In this study, to understand the roles of ALDH2 in rice, we isolated and characterized a cDNA clone encoding another rice ALDH2 (ALDH2b). An in vitro ALDH assay indicated that ALDH2b possesses an NAD(+)-linked activity for oxidation of acetaldehyde, glycolaldehyde and propionaldehyde. Northern blot and immunoblot analyses revealed that ALDH2b was constitutively present in all the organs examined, whereas ALDH2a was expressed in leaves of dark-grown seedlings and panicles. By RFLP linkage mapping, the ALDH2a and ALDH2b genes were mapped to the long arm of chromosome 2 and the short arm of chromosome 6, respectively. We suggest that the rice ALDH2a and ALDH2b genes are orthologues of maize mitochondrial ALDH genes, rf2b and rf2a, respectively. 相似文献
104.
105.
Fukuyama K Yoshida M Yamashita A Deyama T Baba M Suzuki A Mohri H Ikezawa Z Nakajima H Hirai S Ohno S 《The Journal of biological chemistry》2000,275(28):21247-21254
Mitogen-activated protein kinase upstream kinase/dual leucine zipper-bearing kinase/leucine-zipper protein kinase (MUK/DLK/ZPK) is a MAPKKK class protein kinase that induces JNK/SAPK activation. We report here a protein named MBIP that binds to MUK/DLK/ZPK. MUK-binding inhibitory protein (MBIP) contains two tandemly orientated leucine-zipper-like motifs with a cluster of basic amino acids located between the two motifs. MBIP interacts with one of the two leucine-zipper-like motifs of MUK/DLK/ZPK and inhibits the activity of MUK/DLK/ZPK to induce JNK/SAPK activation. Notably, no similar effect was observed with another JNK/SAPK-inducing MAPKKK, COT/Tpl-2, showing the specificity of MBIP action. Furthermore, the overexpression of MBIP partially inhibits the activation of JNK by 0.3 m sorbitol in 293T cells. Taken together, these observations indicate that MBIP can function as a regulator of MUK/DLK/ZPK, a finding that may provide a clue to understanding the molecular mechanism of JNK/SAPK activation by hyperosmotic stress. 相似文献
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108.
αvβ3 expression on blood vessels and melanoma cells in primary lesions; differential association with tumor progression and clinical prognosis 总被引:1,自引:0,他引:1
Kageshita T Hamby CV Hirai S Kimura T Ono T Ferrone S 《Cancer immunology, immunotherapy : CII》2000,49(6):314-318
The αvβ3 integrin has emerged as a key mediator in angiogenesis. Its role in tumor-induced angiogenesis is supported by its up-regulation
in vivo in the vasculature of a number of different types of carcinoma. The potential clinical significance of αvβ3 expression on blood vessels in carcinomas is suggested by its association with tumor progression. Currently no information
is available about the clinical significance of αvβ3 expression on the vasculature of lesions of melanocytic origin. Since we have previously found that αvβ3 expression on melanoma cells in primary lesions is associated with a poor prognosis, in the present study we have compared
αvβ3 expression on blood vessels and on cells of melanocytic origin in nevi and in malignant melanoma lesions. In addition we
have examined the lesions for expression of the αv subunit to gain information on the regulation of αvβ3 expression on endothelial cells and on cells of the melanocyte lineage. αvβ3 expression on endothelial cells and on melanocytic cells was a relatively sensitive and specific marker for malignant lesions.
However, αvβ3 expression on endothelial cells in primary melanoma lesions was not associated with the prognosis of the disease. The αv subunit and the αvβ3 complex were differentially expressed on endothelial cells and on melanocytic cells, implying that different regulatory pathways
control their expression. This finding may account for the differential clinical significance of αvβ3 expression on tumor vasculature and on melanoma cells we observed in our patient cohort. Lastly, αvβ3 may be a useful target for immunotherapeutic approaches in melanoma because of its high expression on the vasculature of
all metastatic lesions tested and its restricted distribution in normal tissues.
Received: 18 February 2000 / Accepted: 12 April 2000 相似文献
109.
Hirai N Kawano H Hirashima O Motoyama T Moriyama Y Sakamoto T Kugiyama K Ogawa H Nakao K Yasue H 《American journal of physiology. Heart and circulatory physiology》2000,279(3):H1172-H1178
Cigarette smoking impairs endothelial function and is one of the major risk factors for atherosclerosis and coronary heart disease. Insulin resistance is associated with major risk factors for atherosclerosis. We examined the effects of vitamin C on insulin sensitivity and endothelial function by measuring steady-state plasma glucose (SSPG) and flow-mediated dilation (FMD) of the brachial artery. We studied 16 current smokers with normal glucose tolerance, 15 nonsmokers with impaired glucose tolerance (IGT), and 17 nonsmokers with normal glucose tolerance as controls. Both SSPG and FMD were blunted in smokers and nonsmokers with IGT compared with controls. In smokers, vitamin C decreased SSPG (P < 0.01 by ANOVA) with decreasing plasma thiobarbituric acid-reactive substances (TBARS) (P < 0.05 by ANOVA) and improved FMD (P < 0.05 by ANOVA). Furthermore, vitamin C improved both SSPG (P < 0.005 by ANOVA) and FMD (P < 0.05 by ANOVA) in nonsmokers with IGT. SSPG, FMD, or TBARS in controls did not change after vitamin C infusion. There was a significant correlation between SSPG and FMD both in smokers and nonsmokers with IGT, whereas no correlation was observed in controls. In conclusion, both insulin sensitivity and endothelial function were impaired in smokers and nonsmokers with IGT and were improved by vitamin C. Thus increased reactive oxygen species play an important role in the pathogenesis of insulin resistance as well as endothelial dysfunction in smokers and nonsmokers with IGT. 相似文献
110.
We found several juvenile hormone-responsive cDNAs in the bean bug, Riptortus clavatus, by using mRNA differential display (Hirai et al., 1998). One of them, a juvenile hormone-repressible cDNA, JR-3, was cloned, sequenced, characterized and identified as a transferrin (RcTf). RcTf cDNA encoded 652 amino acids with a calculated molecular weight of 71,453 Da. The deduced amino acid sequence showed significant homology with the transferin genes of several insects, Manduca sexta (43% identity), Blaberus discoidalis (43%), Aedes aegypti (43%), Drosophila melanogaster (36%), Sarcophaga peregrina (36%) and the human (25%). Antiserum was prepared by using recombinant RcTf protein expressed in Escherichia coli as an antigen. The antiserum reacted specifically with both the recombinant protein and the native protein from the bugs, with sizes of 70 and 75 kDa, respectively. The 75 kDa protein was partially purified from hemolymph of diapausing female bugs and the first ten amino acids were found to be identical to that of RcTf cDNA, indicating that the 75 kDa protein is RcTf. The tissue distribution of RcTf in the bug was examined by Western blot analysis. In diapausing animals, RcTf was detected in the fat body, hemolymph and ovary but not in the gut. In the post-diapause stage, RcTf was also detected in eggs, in addition to the fat body and ovary. These results indicate that RcTf is incorporated into the oocytes during vitellogenesis, and suggest that it may provide iron for the developing embryos. 相似文献