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51.
Seiya Sato Hiroaki Itamochi Nao Oumi Youhei Chiba Tetsuro Oishi Muneaki Shimada Shinya Sato Jun Chikumi Michiko Nonaka Akiko Kudoh Hiroaki Komatsu Tasuku Harada Toru Sugiyama 《Human cell》2016,29(4):181-187
A new cell line of human ovarian clear cell carcinoma (CCC), TU-OC-2, was established and characterized. The cells were polygonal in shape, grew in monolayers without contact inhibition and were arranged in islands like pieces of a jigsaw puzzle. The chromosome numbers ranged from 41 to 96. A low rate of proliferation was observed and the doubling time was 37.5 h. The IC50 values of cisplatin, 7-ethyl-10-hydroxycamptothecin (SN38), which is an active metabolite of camptothecin, and paclitaxel were 7.7 μM, 17.7 nM and 301 nM, respectively. The drug sensitivity assay indicated that TU-OC-2 was sensitive to SN38, but resistant to cisplatin and paclitaxel. Mutational analysis revealed that TU-OC-2 cells have no mutations of PIK3CA in exons 9 and 20 and of TP53 in exons 4–9. We observed the loss of ARID1A protein expression in TU-OC-2 cells by western blot analysis and in the original tumor tissue by immunohistochemistry. This cell line may be useful for studying the chemoresistant mechanisms of CCC and exploring novel therapeutic targets such as the ARID1A-related signaling pathway. 相似文献
52.
Yasuo Oowatari Tetsuro Ogawa Takuya Katsube Kiyohisa Iinuma Hisae Yoshitomi Ming Gao 《Bioscience, biotechnology, and biochemistry》2016,80(8):1594-1601
Hypertrophy of adipocytes in obese adipose tissues causes metabolic abnormality by adipocytokine dysregulation, which promotes type 2 diabetes mellitus, hypertension, and dyslipidemia. We investigated the effects of wasabi (Wasabia japonica Matsum) leaf extracts on metabolic abnormalities in SHRSP.Z-Leprfa/IzmDmcr rats (SHRSP/ZF), which are a model of metabolic syndrome. Male SHRSP/ZF rats aged 7 weeks were divided into two groups: control and wasabi leaf extract (WLE) groups, which received water or oral treatment with 4 g/kg/day WLE for 6 weeks. WLE improved the body weight gain and high blood pressure in SHRSP/ZF rats, and the plasma triglyceride levels were significantly lower in the WLE group. Adipocyte hypertrophy was markedly prevented in adipose tissue. The expression of PPARγ and subsequent downstream genes was suppressed in the WLE group adipose tissues. Our data suggest that WLE inhibits adipose hypertrophy by suppressing PPARγ expression in adipose tissue and stimulating the AMPK activity by increased adiponectin. 相似文献
53.
Participation of caspase-3-like protease in oxidation-induced impairment of erythrocyte membrane properties 总被引:1,自引:0,他引:1
Erythrocytes are very susceptible to oxidative stress, having a high content of intracellular oxygen and hemoglobin. In the present study, exposure to oxidative stress resulted in a significant impairment of erythrocyte membrane functions, such as deformability and anion exchange. Band 3 protein, also known as anion exchanger-1, plays an important role in these two functions. We show that oxidative stress activated caspase-3 inside the erythrocytes, which resulted in band 3 protein cleavage. Interestingly, inhibition of the caspase-3 with its specific inhibitor not only suppressed the digestion of band 3 protein, but also blunted the functional damage to erythrocytes, such as deformability and anion exchange, without changing the level of peroxidation of membrane lipids. These results provide experimental evidence that activation of caspase-3 plays an important role in the oxidative stress-induced impairment of membrane functions of erythrocytes. 相似文献
54.
55.
T Nishinaka R Kodaka H Nanjo T Terada T Mizoguchi T Nishihara 《The International journal of biochemistry》1992,24(11):1737-1742
1. Two isozymes of glutathione S-transferase (GST-dl1 and GST-dl2) were purified to homogeneity from dog lens. 2. The subunit size and the isoelectric point were determined to be 24,000 and > pI 9.5 for GST-dl1 and 22,000 and pI 8.1 for GST-dl2. 3. It was judged that GST-dl1 is a class alpha enzyme and GST-dl2 belongs to class pi on the basis of their immunological properties and N-terminal amino acid sequences. 4. The expression pattern of glutathione S-transferase isoenzymes in dog lens is different from that in pig, rat and bovine lenses. 相似文献
56.
Movie presentation can act as an enrichment technique for nonhuman primates, who also show preferences for certain contents. This study investigated the video preferences and effects of movies on behavioral abnormalities in single-caged Japanese macaques. When movie rewards were provided for subjects' touch responses, the subjects maintained the touch responses during 40 2-hr sessions. Although repeated presentation of 1 stimulus set decreased the subject's touch response, changing the stimulus set led to recovery of this response. The subjects showed clear preferences, consistent across 2 different stimulus sets, for movies showing humans or animation (61.1% of total duration). Subjects consistently played movies both with and without their preferred content. The availability of a variety of contents might be important for attracting subjects' interest. The frequency with which monkeys engaged in abnormal behaviors decreased in the experimental (20.9%) and the postexperimental (25.6%) periods compared with the preexperimental period (33.5%). Movie presentations could keep attracting the interest of single-caged monkeys in their visual environment, ameliorating their behavioral abnormalities for some time. In summary, social experience during infancy might influence Japanese macaques' movie preferences. 相似文献
57.
58.
Eutrophication of mountain lakes in Japan due to increasing deposition of anthropogenically produced dust 总被引:2,自引:0,他引:2
Narumi K. Tsugeki Tetsuro Agusa Shingo Ueda Michinobu Kuwae Hirotaka Oda Shinsuke Tanabe Yukinori Tani Kazuhiro Toyoda Wan-lin Wang Jotaro Urabe 《Ecological Research》2012,27(6):1041-1052
Atmospheric dust has wide-reaching effects, not only influencing climate conditions, but also ecosystems. The eastern region of the Asian continent is one of the largest emitters of dust in the world, and recent economic growth in the region has been accompanied by an increase in anthropogenic emissions. However, the effects of increased Asian dusts on aquatic ecosystems are not well understood. We examined fossil pigments and zooplankton remains from 210Pb-dated sediments taken from high mountain lakes of Hourai-Numa and Hachiman-Numa, located in the Towada-Hachimantai National Park of Japan Islands, to uncover historical changes in the phyto- and zooplankton community over the past 100?years. Simultaneously, we measured the geochemical variables of TOC, TN, TP, ??13C, ??15N, and lead isotopes (207Pb/206Pb, 208Pb/206Pb) in the sediments to identify environmental factors causing such changes. As a result, despite few anthropogenic activities in the watersheds, alpine lakes in Japan had increased algal and herbivore plankton biomasses by 3?C6 fold for recent years depending on the surrounding terrestrial vegetation and landscape conditions. Biological and biogeochemical proxies recorded from the lake sediments showed that this eutrophication occurred after the 1990s when P deposition increased as a result of atmospheric loading of dust transported from the Asian continent. The continued increase of anthropogenically produced dust may therefore impart damaging impacts on mountain ecosystems even if they are protected from direct anthropogenic disturbances. 相似文献
59.
Although the electrolytically obtained DPNH was not completely oxidized by usual dehydrogenases or diaphorases, one of the authors noticed that its absorption band at 340 mμ disappeared completely when it was incubated with the extract of mung been seedlings. The reaction was found to be stimulated by the addition of methylene blue, and the product was identified as DPN. Thus, the reaction resembled that of diaphorase, although it was less specific to the configuration of DPNH. But unlike usual diaphorase, it required a cofactor, which was neither flavins nor metallic ion, but an unidentified acidic substance. General properties of the enzyme and the cofactor are reported in this article. 相似文献
60.
TRPA1 mediates the inflammatory actions of environmental irritants and proalgesic agents 总被引:44,自引:0,他引:44
Bautista DM Jordt SE Nikai T Tsuruda PR Read AJ Poblete J Yamoah EN Basbaum AI Julius D 《Cell》2006,124(6):1269-1282
TRPA1 is an excitatory ion channel targeted by pungent irritants from mustard and garlic. TRPA1 has been proposed to function in diverse sensory processes, including thermal (cold) nociception, hearing, and inflammatory pain. Using TRPA1-deficient mice, we now show that this channel is the sole target through which mustard oil and garlic activate primary afferent nociceptors to produce inflammatory pain. TRPA1 is also targeted by environmental irritants, such as acrolein, that account for toxic and inflammatory actions of tear gas, vehicle exhaust, and metabolic byproducts of chemotherapeutic agents. TRPA1-deficient mice display normal cold sensitivity and unimpaired auditory function, suggesting that this channel is not required for the initial detection of noxious cold or sound. However, TRPA1-deficient mice exhibit pronounced deficits in bradykinin-evoked nociceptor excitation and pain hypersensitivity. Thus, TRPA1 is an important component of the transduction machinery through which environmental irritants and endogenous proalgesic agents depolarize nociceptors to elicit inflammatory pain. 相似文献