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71.
A novel gene, CRR9, which was up-regulated in CDDP-resistant ovarian tumor cell line, was associated with apoptosis 总被引:2,自引:0,他引:2
Yamamoto K Okamoto A Isonishi S Ochiai K Ohtake Y 《Biochemical and biophysical research communications》2001,280(4):1148-1154
In the screening for cisplatin (CDDP)-resistance related genes by a mRNA differential display method, we detected some increased bands in CDDP resistant ovarian tumor cell line 2008/C13*5.25. One of them, named DD9, was a positive fragment on Northern blot analysis. We cloned it as a full length cDNA by 5'RACE and found a novel gene, CRR9 (Cisplatin Resistance Related gene 9). The CRR9 gene was transcribed into a 2.0 kb mRNA, encoding 512 amino acids. The putative protein had transmembrane-like domains and well conserved on C terminus with human CLPTM1 and the homologs found in Drosophila and C. elegans. Transfection assay showed that the CDDP-sensitive strain 2008 with CRR9 was more sensitive to CDDP, indicating that CRR9 was not associated with the CDDP-resistance, but the CDDP-induced apoptosis. 相似文献
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Noritsugu Yabe Yasuharu Itagaki Morimasa Tanimoto Hisao Matsui 《Biotechnology letters》1999,21(12):1083-1089
Bovine milk lactoferrin (2 to 20 g ml–1) changed enhancement of [3H]thymidine incorporation by phytohemagglutinin-stimulated rat spleen lymphocytes into suppression as their lactoferrin-withdrawal incorporation increased to greater than 10000 cpm culture–1 under the present isotope-labeling conditions. The enhancement disappeared by 15-min delayed addition of lactoferrin after addition of lectin. There was no lactoferrin effect when the cells were stimulated with 12-O-tetradecanoylphorbol-13-acetate plus ionomycin. Thus, lactoferrin has a certain extracellular effect on lymphocyte proliferation in response to the lectin. 相似文献
74.
Kohno K Okamoto I Sano O Arai N Iwaki K Ikeda M Kurimoto M 《Bioscience, biotechnology, and biochemistry》2004,68(1):138-145
In this study, we have examined the anti-inflammatory actions of royal jelly (RJ) at a cytokine level. When supernatants of RJ suspensions were added to a culture of mouse peritoneal macrophages stimulated with lipopolysaccharide and IFN-gamma, the production of proinflammatory cytokines, such as TNF-alpha, IL-6, and IL-1, was efficiently inhibited in a dose-dependent manner without having cytotoxic effects on macrophages. This suggests that RJ contains factor(s) responsible for the suppression of proinflammatory cytokine secretion. We named the factor for honeybees RJ-derived anti-inflammatory factor (HBRJ-AIF), and further investigated the molecular aspects of it. Size fractionation study showed that HBRJ-AIF is composed of substances of low (< 5 kDa) and high (> 30 kDa) molecular weights, with the former being a major component. Chromatographic analysis showed that MRJP3 is one candidate for the HBRJ-AIF with high molecular weights. Thus, our results suggest that RJ has anti-inflammatory actions through inhibiting proinflammatory cytokine production by activated macrophages. 相似文献
75.
Identification of major proteins in maize egg cells 总被引:15,自引:0,他引:15
Okamoto T Higuchi K Shinkawa T Isobe T Lörz H Koshiba T Kranz E 《Plant & cell physiology》2004,45(10):1406-1412
In most flowering plants, the female gametophyte develops in an ovule deeply embedded in the ovary. Through double fertilization, the egg cell fuses with the sperm cell, resulting in a zygote, which develops into the embryo. In the present study, we analyzed egg cell lysates by polyacrylamide gel electrophoresis and subsequent mass spectrometry-based proteomics technology, and identified major protein components expressed in the egg cell. The identified proteins included three cytosolic enzymes of the glycolytic pathway, glyceraldehyde-3-phosphate dehydrogenase, 3-phosphoglycerate kinase and triosephosphate isomerase, two mitochondrial proteins, the ATP synthase beta-subunit and an adenine nucleotide transporter, and annexin p35. In addition, expression levels of these proteins in the egg cell were compared with those in the early embryo, the central cell and the suspension cell. Annexin p35 was highly expressed only in the egg cell, and glyceraldehyde-3-phosphate dehydrogenase, 3-phosphoglycerate kinase and the adenine nucleotide transporter were expressed at higher levels in egg cells than in central and cultured cells. These results indicate that annexin p35 in the egg cell and zygote is involved in the exocytosis of cell wall materials, which is induced by a fertilization-triggered increase in cytosolic Ca2+ levels, and that the egg cell is rich in an enzyme subset for the energy metabolism. 相似文献
76.
Ochiai H Ohtani T Ishida A Kusumi K Kato M Kohno H Kishikawa K Obata T Nakai H Toda M 《Bioorganic & medicinal chemistry letters》2004,14(1):207-210
Based on the hypothesis that the dose-limiting side effects of PDE4 inhibitors could be mediated via the central nervous system (CNS), design and synthesis of a hydrophilic analogue is considered to be one approach to improving the side-effect profile of Ariflo 1. Water-soluble piperidine derivatives were found to possess therapeutic potential. 相似文献
77.
M. Ikeda T. Ezaki T. Tsukahara J. Moriguchi K. Furuki Y. Fukui S.H. Ukai Okamoto H. Sakurai 《Biometals》2004,17(5):539-541
The purpose of the study was to examine the validity of alpha1-microglobulin (alpha1-MG) in comparison with popularly used beta2-microglobulin (beta2-MG). A database was revisited to select ca. 7,500 spot urine samples (of adequate urine density) from non-pregnant, non-lactating and never-smoking adult women. The validity of the MGs was examined in terms of stability of the MG-uria prevalence in urine samples of various creatinine (CR or cr) concentration or specific gravity (SG or sg). Comparisons were made for MGs as observed (e.g., alpha1-MGob), as corrected for CR (e.g., alpha1-MGcr) and as corrected for SG of 1.016 (e.g., alpha1-MGsg). A cut-off value of 5.7 mg/g cr (or mg/l) for alpha1-MG was deduced from a cut-off value of 400 microg/g cr (or mcirog/l) for beta2-MG, because the correlation between alpha1-MGcr and beta2-MGcr was statistically significant. The prevalence of a 1-MGsg-uria was essentially unchanged (i.e., from a low of 13.6% to a high of 17.0%, or 1.2 times) except for in very dense or very thin urine samples, in contrast, beta2-MGcr-uria showed a substantial increase (from 0.0% to 2.8% with an infinite rate) as a reverse function of a decrease in CR in urine. The prevalence of uncorrected markers, i.e., alpha1-MGob-uria and beta2-MGob-uria, showed even greater CR- or SG-dependent changes. Thus, it appeared prudent to consider a alpha-MGsg rather than beta2-MGcr as a marker of tubular dysfunction among a general population with various urine density. 相似文献
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Margono SS Ito A Sato MO Okamoto M Subahar R Yamasaki H Hamid A Wandra T Purba WH Nakaya K Ito M Craig PS Suroso T 《Journal of helminthology》2003,77(1):39-42
A preliminary study to detect human worm carriers of Taenia solium in Papua (Irian Jaya), Indonesia was carried out using stool examinations for the detection of copro-antigens and adult proglottids after chemotherapy, and confirmation by mitochondrial DNA analysis using expelled proglottids and metacestodes developed in NOD/Shi-scid mice from eggs of expelled proglottids. Approximately 8.6% of the local population in Kama (5/58), 1 km from the local capital city centre, Wamena, were confirmed to harbour adult T. solium using these techniques. 相似文献