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41.
Takabatake T Kakinuma S Hirouchi T Nakamura MM Fujikawa K Nishimura M Oghiso Y Shimada Y Tanaka K 《Radiation research》2008,169(4):426-436
Radiation-induced thymic lymphoma in mice is a useful model for studying both the mechanism of radiation carcinogenesis and genetic susceptibility to tumor development. Using array-comparative genomic hybridization, we analyzed genome-wide changes in DNA copy numbers in radiation-induced thymic lymphomas that had developed in susceptible C57BL/6 and resistant C3H mice and their hybrids, C3B6F1 and B6C3F1 mice. Besides aberrations at known relevant genetic loci including Ikaros and Bcl11b and trisomy of chromosome 15, we identified strain-associated genomic imbalances on chromosomes 5, 10 and 16 and strain-unassociated trisomy of chromosome 14 as frequent aberrations. In addition, biallelic rearrangements at Tcrb were detected more frequently in tumors from C57BL/6 mice than in those from C3H mice, suggesting aberrant V(D)J recombination and a possible link with tumor susceptibility. The frequency and spectrum of these copy-number changes in lymphomas from C3B6F1 and B6C3F1 mice were similar to those in C57BL/6 mice. Furthermore, the loss of heterozygosity analyses of tumors in F(1) mice indicated that allelic losses at Ikaros and Bcl11b were caused primarily by multilocus deletions, whereas those at the Cdkn2a/Cdkn2b and Pten loci were due mainly to uniparental disomy. These findings provide important clues to both the mechanisms for accumulation of aberrations during radiation-induced lymphomagenesis and the different susceptibilities of C57BL/6 and C3H mice. 相似文献
42.
Taking advantage of the phenomenon that animal cells adhering to a culture substrate are temporarily immobilized by light irradiation, we established a technique to manipulate the cells adhering to a culture substrate under microscopic observation. Using this technique, we demonstrated a separation of cells adhering to a culture substrate and fabrication of an elaborately patterned co-culture system. 相似文献
43.
To clarify the control of glycolysis and the fermentation pattern in Streptococcus bovis, the molecular and enzymatic properties of NAD+-specific glyceraldehyde-3-phosphate dehydrogenase (GAPDH) were examined. The GAPDH gene (gapA) was found to cluster with several others, including those that encode phosphoglycerate kinase and translation elongation
factor G, however, gapA was transcribed in a monocistronic fashion. Since biochemical properties, such as optimal pH and affinity for glyceraldehyde-3-phosphate
(GAP), were not very different between GAPDH- and NADP+-specific glyceraldehyde-3-phosphate dehydrogenase (GAPN), the flux from GAP may be greatly influenced by the relative amounts
of these two enzymes. Using S. bovis JB1 as a parent, JB1gapA and JB1ldh, which overproduce GAPDH and lactate dehydrogenase (LDH), respectively, were constructed to examine the control of the glycolytic
flux and lactate production. There were no significant differences in growth rates and formate-to-lactate ratios among JB1,
JB1gapA, and JB1ldh grown on glucose. When grown on lactose, JB1ldh showed a much lower formate-to-lactate ratio than JB1gapA, which showed the highest NADH-to-NAD+ ratio. However, growth rates did not differ among JB1, JB1gapA, and JB1ldh. These results suggest that GAPDH is not involved in the control of the glycolytic flux and that lactate production is mainly
controlled by LDH activity. 相似文献
44.
45.
Novel compounds were designed based on fenretinide, N-(4-hydroxyphenyl)retinamide (2), which is a synthetic amide of all-trans-retinoic acid (1) that is a potent antioxidant and anticancer agent. Our recent findings indicated that antioxidant and anticancer activities were due to p-methylaminophenol moiety (8) in 2, and that p-octylaminophenol (7), which has an elongated alkyl chain, was more potent than 8. This finding lets us to investigate whether compounds containing alkyl or acyl chains linked to an aminophenol residue as long as 2 and 1, would show activities greater than 2. For this purpose, we prepared p-dodecanoylaminophenol (3), p-decanoylaminophenol (4), p-dodecylaminophenol (5), and p-decylaminophenol (6). The p-alkylaminophenols, 5 and 6, exhibited superoxide scavenging activities, but not p-acylaminophenols, 3 and 4. Elongation of the alkyl chain length reduced superoxide trapping capability (8>7>6>5). In contrast, lipid peroxidation in rat liver microsomes was reduced by 5 and 6 in dose-dependent manner. Compounds 3 and 4 were poor lipid peroxidation inhibitors, being approximately 400- to 1300-fold lower than 5 and 6. In addition, all compounds inhibited cell growth of human leukemia cell lines, HL60 and HL60R, in dose-dependent manners (5>6>3=4). The HL60R cell line is resistant against 1. Growth of both cell lines was suppressed by 5 and 6 in a fashion dependent on the length of the aminophenol alkyl chain, but not by 3 and 4. These results indicate that 5, a potent anticancer agent greater than 2, may potentially have clinical utility, and that its anticancer activity is correlated with inhibitory potency against lipid peroxidation, but not with superoxide scavenging activity. 相似文献
46.
Tanaka KJ Ogawa K Takagi M Imamoto N Matsumoto K Tsujimoto M 《The Journal of biological chemistry》2006,281(52):40096-40106
mRNAs in eukaryotic cells are presumed to always associate with a set of proteins to form mRNPs. In Xenopus oocytes, a large pool of maternal mRNAs is masked from the translational apparatus as storage mRNPs. Here we identified Xenopus RAP55 (xRAP55) as a component of RNPs that associate with FRGY2, the principal component of maternal mRNPs. RAP55 is a member of the Scd6 or Lsm14 family. RAP55 localized to cytoplasmic foci in Xenopus oocytes and the processing bodies (P-bodies) in cultured human cells: in the latter cells, RAP55 is an essential constituent of the P-bodies. We isolated xRAP55-containing complexes from Xenopus oocytes and identified xRAP55-associated proteins, including a DEAD-box protein, Xp54, and a protein arginine methyltransferase, PRMT1. Recombinant xRAP55 repressed translation, together with Xp54, in an in vitro translation system. In addition, xRAP55 repressed translation in oocytes when tethered with a reporter mRNA. Domain analyses revealed that the N-terminal region of RAP55, including the Lsm domain, is important for the localization to P-bodies and translational repression. Taken together, our results suggest that xRAP55 is involved in translational repression of mRNA as a component of storage mRNPs. 相似文献
47.
Tatsuo Kawarasaki Masaru Sone Mitsutoshi Yoshida Kimio Bamba 《Molecular reproduction and development》1996,43(4):548-553
This study was carried out to develop a rapid and simultaneous detection system of chromosome Y- and 1-bearing porcine spermatozoa by fluorescence in situ hybridization (FISH). Chromosome Y- and 1-specific DNA probes were produced by polymerase chain reaction with digoxigenin (Dig)- or biotin-dUTP. The hybridization probe mixture of labeled Y-chromosome and chromosome 1-specific DNA was applied to the preparation, immediately denatured at 75°C for 8 min, hybridized for 5 min at 37°C and overall FISH steps were done within a few hours. When double FISH with Dig-labeled chromosome Y-specific and biotin-labeled chromosome 1-specific probes was applied to sperm nuclei pretreated with dithiothreitol, the average of 50.9% of sperm nuclei had the Dig-signal, 99.2% of the sperm nuclei had the biotin-signal and the average of 0.3% of sperm nuclei showed no signal. The putative rate of Y-bearing spermatozoa ranged from 49.8% to 52.8% among 5 boars and the average putative rate of Y-bearing spermatozoa was 51.0%. The results indicated that a rapid and simultaneous FISH with chromosome Y- and 1-specific porcine DNA probes produced by PCR made possible more accurate assessment of Y-bearing porcine spermatozoa. © 1996 Wiley-Liss, Inc. 相似文献
48.
Mitsuru Tsuji Nongluk Sriwilaijaroen Hideo Inoue Kazuhiko Miki Kaoru Kinoshita Kiyotaka Koyama Kimio Furuhata Yasuo Suzuki Kunio Takahashi 《Bioorganic & medicinal chemistry》2018,26(1):17-24
We are interested in new non-natural glycosides with sialic acid conjugates and their biological activities. We report the synthesis of eleven non-natural occurring glycosides, which are triterpene (glycyrrhetinic acid and its derivatives)-sialic acid conjugates, and their inhibitory activities against influenza virus sialidases and influenza virus multiplication in MDCK host cells. Deoxoglycyrrhetol-sialic acid conjugates (6d and 6e) and oleanolic acid-sialic acid conjugates (7d and 7e) showed strong inhibitory activities against three subtypes of influenza virus sialidases. These four compounds (6d, 6e, 7d and 7e) showed clear inhibition to influenza virus multiplication but not to MDCK host cell survival. 相似文献
49.
Nobuo Moriyama Shigeharu Kurimoto Shigeo Horie Kimio Nasu Teruo Tanaka Kenichi Yano Hiroshi Hirano Gozo Tsujimoto Kazuki Kawabe 《The Histochemical journal》1996,28(4):283-288
Summary Adrenergic stimulation induces contraction of hypertrophied prostatic tissue via the α1 adrenoceptor, and the results of pharmacological studies suggested the existence of adrenoceptor subtypes. Recently three
subtypes (α1a, α1b, and α1d) were cloned. Using probes for these subtypes, we demonstrated their expression in the tissues of ten cases of benign prostatic
hypertrophy, usingin situ hybridization. To determine the ratio between these subtypes, an RNase protection assay was also performed in three cases.
Expression of the α1a and α1d adrenoceptors was diffuse in the smooth muscles of the interstitium, but was absent in glandular epithelial cells. On the
contrary, the α1b adrenoceptor was hardly detectable. The RNase protection assay confirmed the absence of the α1b adrenoceptor, the ratio of α1a and α1d being 4∶1. These results supported the idea that the differences in prostatic contractile response to several adrenergic
drugs are based on the affinities of these drugs for the different subtypes. 相似文献
50.
Hiromitsu Takayama Yasuo Iimura Mariko Kitajima Norio Aimi Kenji Konno Hiroshi Inoue Masatoshi Fujiwara Tadashi Mizuta Tomoyuki Yokota Shiro Shigeta Kenji Tokuhisa Yasuaki Hanasaki Kimio Katsuura 《Bioorganic & medicinal chemistry letters》1997,7(24):290-3148
An indole alkaloid, hirsutine (1), was found to exhibit potent inhibitory effect against influenza A virus in vitro, and the essential structural feature for revealing the activity was elucidated by study of the structure-activity relationship using natural and synthetic derivatives of 1. 相似文献