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961.
962.
Didier Pélaprat Jean-Marie Zajac Gilles Gacel Christiane Durieux Jean-Louis Morgat André Sasaki Bernard P. Roques 《Life sciences》1985,37(26):2483-2490
Preliminary results on the binding of [3H]Boc[Nle28,31]CCK27?33, designated [3H]Boc[diNle]CCK7, on mouse brain and rat pancreas membranes are presented. This new ligand for CCK receptors possesses a high specific activity (144 Ci/mmole), and binds in a saturable manner to mouse brain (Kd = 0.49 nM, Bmax = 49 fmoles/mg protein) and rat pancreas (Kd = 4.4 nM, Bmax = 696 fmoles/mg protein). Unlabelled Boc[diNle]CCK7 displaces [125I]CCK8 from its binding sites on mouse brain membranes with a high affinity, slightly superior to that of CCK8. The order of potencies to displace [3H]Boc[diNle]CCK7 from its binding sites was the same on mouse brain and rat pancreas: , the pancreas binding sites being more discriminative than the brain binding sites. Thus, [3H]Boc[diNle]CCK7 is a very promising new probe for the characterization of CCK receptors and their interaction with different CCK fragments. 相似文献
963.
Ohsawa K Nakagawa SY Kimura M Shimada C Tsuda S Kabasawa K Kawaguchi S Sasaki YF 《Mutation research》2003,539(1-2):65-76
The genotoxicity of endogenously formed N-nitrosamines from secondary amines and sodium nitrite (NaNO(2)) was evaluated in multiple organs of mice, using comet assay. Groups of four male mice were orally given dimethylamine, proline, and morpholine simultaneously with NaNO(2). The stomach, colon, liver, kidney, urinary bladder, lung, brain, and bone marrow were sampled 3 and 24 h after these compounds had been ingested. Although secondary amines and the NaNO(2) tested did not yield DNA damage in any of the organs tested, DNA damage was observed mainly in the liver following simultaneous oral ingestion of these compounds. The administration within a 60 min interval also yielded hepatic DNA damage. It is considered that DNA damage induced in mouse organs with the coexistence of amines and nitrite in the acidic stomach is due to endogenously formed nitrosamines. Ascorbic acid reduced the liver DNA damage induced by morpholine and NaNO(2). Reductions in hepatic genotoxicity of endogenously formed N-nitrosomorpholine by tea polyphenols, such as catechins and theaflavins, and fresh apple, grape, and orange juices were more effective than was by ascorbic acid. In contrast with the antimutagenicity of ascorbic acid in the liver, ascorbic acid yielded stomach DNA damage in the presence of NaNO(2) (in the presence and absence of morpholine). Even if ascorbic acid acts as an antimutagen in the liver, nitric oxide (NO) formed from the reduction of NaNO(2) by ascorbic acid damaged stomach DNA. 相似文献
964.
Gene amplification profiling of esophageal squamous cell carcinomas by DNA array CGH 总被引:6,自引:0,他引:6
Ishizuka T Tanabe C Sakamoto H Aoyagi K Maekawa M Matsukura N Tokunaga A Tajiri T Yoshida T Terada M Sasaki H 《Biochemical and biophysical research communications》2002,296(1):152-155
Gene amplification is one of the basic mechanisms that lead to overexpression of oncogenes. DNA array comparative genomic hybridization (CGH) has great potential for comprehensive analysis of both a relative gene-copy number and altered chromosomal regions in cancers, which enables us to identify new amplified genes and unstable chromosomal loci. We examined the amplification status in 32 esophageal squamous cell carcinomas (ESCCs) and 13 ESCC cell lines on 51 frequently amplified loci in a variety of cancers by both DNA array CGH and Southern blot analyses. The 1p34 locus containing MYCL1, 2p24 (MYCN), 7p12 (EGFR), and 12q14 (MDM2) were amplified in one of the 32 cases (3%), and the 17q12 locus (ERBB2) and 8p11 (FGFR1) in two of the 32 cases (6%), while only the 11q13 locus (Cyclin D1, FGF4, and EMS1) was frequently amplified (28%, 9/32), demonstrating this locus to be a major target in ESCCs. One locus, 8q24 (c-MYC) was found to be amplified only in the cell lines. Eight out of 51 loci (15.7%) were found to be amplified in at least one of the 32 primary ESCCs or the 13 ESCC cell lines, suggesting that chromosomal loci frequently amplified in a type of human cancer may also be amplified in other types of cancers. This paper is the first report of an application of DNA array CGH to ESCCs. 相似文献
965.
966.
Masami Suzuki Fumiko Chiwaki Yumi Sawada Maho Ashikawa Kazuhiko Aoyagi Takeshi Fujita Kazuyoshi Yanagihara Masayuki Komatsu Minoru Narita Tsutomu Suzuki Hiroshi Nagase Ryoji Kushima Hiromi Sakamoto Takeo Fukagawa Hitoshi Katai Hitoshi Nakagama Teruhiko Yoshida Yasuhito Uezono Hiroki Sasaki 《PloS one》2015,10(4)
The dormancy of tumor cells is a major problem in chemotherapy, since it limits the therapeutic efficacy of anti-tumor drugs that only target dividing cells. One potential way to overcome chemo-resistance is to “wake up” these dormant cells. Here we show that the opioid antagonist methylnaltrexone (MNTX) enhances the effect of docetaxel (Doc) by blocking a cell growth-suppressive pathway. We found that PENK, which encodes opioid growth factor (OGF) and suppresses cell growth, is predominantly expressed in diffuse-type gastric cancers (GCs). The blockade of OGF signaling by MNTX releases cells from their arrest and boosts the effect of Doc. In comparison with the use of Doc alone, the combined use of Doc and MNTX significantly prolongs survival, alleviates abdominal pain, and diminishes Doc-resistant spheroids on the peritoneal membrane in model mice. These results suggest that blockade of the pathways that suppress cell growth may enhance the effects of anti-tumor drugs. 相似文献
967.
A new moray,Gymnothorax prolatus, is described from a single specimen from Taiwan. The new species is distinctive in its combination of a slender body (depth
28 in TL) with anus at midbody, smooth-edged teeth, numerous vertebrae (187), and uniformly dark brown body and fins. 相似文献
968.
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