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81.
From Picrasma javanica, five new quassinoid glucosides, javanicinosides D-H, together with known quassinoids, neoquassin and picrasin A and triterpenoids, hispidol A and lanosta-7,24-dien-3-one were isolated. The structures have been determined by spectral analysis and chemical evidence. 相似文献
82.
83.
Uchino K Hirano G Hirahashi M Isobe T Shirakawa T Kusaba H Baba E Tsuneyoshi M Akashi K 《Experimental cell research》2012,318(15):1799-1807
There is emerging evidence that human solid tumor cells originate from cancer stem cells (CSCs). In cancer cell lines, tumor-initiating CSCs are mainly found in the side population (SP) that has the capacity to extrude dyes such as Hoechst 33342. We found that Nanog is expressed specifically in SP cells of human gastrointestinal (GI) cancer cells. Nucleotide sequencing revealed that NanogP8 but not Nanog was expressed in GI cancer cells. Transfection of NanogP8 into GI cancer cell lines promoted cell proliferation, while its inhibition by anti-Nanog siRNA suppressed the proliferation. Immunohistochemical staining of primary GI cancer tissues revealed NanogP8 protein to be strongly expressed in 3 out of 60 cases. In these cases, NanogP8 was found especially in an infiltrative part of the tumor, in proliferating cells with Ki67 expression. These data suggest that NanogP8 is involved in GI cancer development in a fraction of patients, in whom it presumably acts by supporting CSC proliferation. 相似文献
84.
85.
Sekikawa A Steingrimsdottir L Ueshima H Shin C Curb JD Evans RW Hauksdottir AM Kadota A Choo J Masaki K Thorsson B Launer LJ Garcia ME Maegawa H Willcox BJ Eiriksdottir G Fujiyoshi A Miura K Harris TB Kuller LH Gudnason V 《Prostaglandins, leukotrienes, and essential fatty acids》2012,87(1):11-16
In the 1990s Iceland and Japan were known as countries with high fish consumption whereas coronary heart disease (CHD) mortality in Iceland was high and that in Japan was low among developed countries. We described recent data fish consumption and CHD mortality from publicly available data. We also measured CHD risk factors and serum levels of marine-derived n-3 and other fatty acids from population-based samples of 1324 men in Iceland, Japan, South Korea, and the US. CHD mortality in men in Iceland was almost 3 times as high as that in Japan and South Korea. Generally, a profile of CHD risk factors in Icelanders compared to Japanese was more favorable. Serum marine-derived n-3 fatty acids in Iceland were significantly lower than in Japan and South Korea but significantly higher than in the US. 相似文献
86.
Tsuruhami K Mori S Amarume S Saruwatari S Murata T Hirakake J Sakata K Usui T 《Bioscience, biotechnology, and biochemistry》2006,70(3):691-698
p-Nitrophenyl and eugenyl beta-primeveroside (6-O-beta-D-xylopyranosyl-beta-D-glucopyranoside) hydrolytic activity was found in culture filtrate from Penicillium multicolor IAM7153, and the enzyme was isolated. The enzyme was purified as a beta-primeverosidase-like enzyme by precipitation with ammonium sulfate followed by successive chromatographies on Phenyl Sepharose, Mono Q, and beta-galactosylamidine affinity columns. The molecular mass was estimated to be 50 kDa by SDS-PAGE and gel filtration. The purified enzyme was highly specific toward the substrate p-nitrophenyl beta-primeveroside, which was cleaved in an endo-manner into primeverose and p-nitrophenol, but a series of beta-primeveroside as aroma precursors were hydrolyzed only slightly as substrates for the enzyme. In analyses of its hydrolytic action and kinetics, the enzyme showed narrow substrate specificity with respect to the aglycon and glycon moieties of the diglycoside. We conclude that the present enzyme is a kind of beta-diglycosidase rather than beta-primeverosidase. 相似文献
87.
The structure and expression of SEPALLATA-like genes in Asparagus species (Asparagaceae) 总被引:2,自引:0,他引:2
88.
Takafumi Mizushige Katsuyoshi Saitoh Yasuko Manabe Taichi Nishizuka Yuichi Taka Ai Eguchi Takeshi Yoneda Shigenobu Matsumura Satoshi Tsuzuki Kazuo Inoue Tohru Fushiki 《Life sciences》2009,84(21-22):760-765
AimsTo determine whether beta-endorphin contributes to the ingestion of and preference for dietary oil, we examined the relationship between the dynamics of beta-endorphin, before and after the ingestion of corn oil, and the intake volume of corn oil.Main methodsRats were offered 5% corn oil for 20 min for 5 consecutive days so they could acquire a preference for corn oil. On day 6, seven groups of rats were presented with the oil for defined time periods, and we measured the beta-endorphin levels in the serum and cerebrospinal fluid (CSF) before and after the presentation of corn oil as well as the consumed volume of corn oil at defined time points.Key findingsBeta-endorphin levels in serum and CSF were significantly increased 15 min after the ingestion of corn oil, followed by a rapid decrease and maintenance at the basal level throughout the rest of the experimental period. The intake of corn oil was the lowest in the time period of 15–30 min, when the beta-endorphin level reached a peak value. The intake volume of corn oil might be inversely correlated with beta-endorphin levels in serum and CSF. The pretreatment of naloxone, an antagonist of the opioid receptor, decreased the initial licking rate for corn oil and increased the latency for corn oil in the licking test.SignificanceThe beta-endorphin was rapidly released after oil ingestion, which contributed to the hedonic preference and ingestive behavior for fat. 相似文献
89.
Boron Nutrition of Tobacco BY-2 Cells. V. Oxidative Damage is the Major Cause of Cell Death Induced by Boron Deprivation 总被引:1,自引:1,他引:0
Boron (B) is an essential micronutrient for vascular plants.However, it remains unclear how B deficiency leads to variousmetabolic disorders and cell death. To understand this mechanism,we analyzed the physiological changes in suspension-culturedtobacco (Nicotiana tabacum) BY-2 cells upon B deprivation. When3-day-old cells were transferred to B-free medium, cell deathwas detectable as early as 12 h after treatment. The B-deprivedcells accumulated more reactive oxygen species and lipid peroxidesthan control cells, and showed a slight but significant decreasein the cellular ascorbate pool. Supplementing the media withlipophilic antioxidants effectively suppressed the death ofB-deprived cells, suggesting that the oxidative damage is theimmediate and major cause of cell death under B deficiency.Dead cells in B-free culture exhibited a characteristic morphologywith a shrunken cytoplasm, which is often seen in cells undergoingprogrammed cell death (PCD). However, they did not display otherhallmarks of PCD such as internucleosomal DNA fragmentation,decreased ascorbate peroxidase expression and protection fromdeath by cycloheximide. These results suggest that the deathof tobacco cells induced by B deprivation is not likely to bea typical PCD. 相似文献
90.
Yasuyuki Nakamura Akira Sekikawa Takashi Kadowaki Aya Kadota Sayaka Kadowaki Hiroshi Maegawa Yoshikuni Kita Rhobert W. Evans Daniel Edmundowicz J. David Curb Hirotsugu Ueshima 《Obesity (Silver Spring, Md.)》2009,17(6):1269-1273
Adiponectin is reduced in obesity and has been suggested to play an important role in modulation of atherosclerosis. We studied the relationship between visceral (VAT) and subcutaneous (SAT) adipose tissue and serum adiponectin concentrations in Japanese men. Participants were 304 randomly selected community-based Japanese men aged 40–49 without a prior history of cardiovascular disease. Participants were grouped according to tertiles of serum adiponectin. In multiple linear regression analysis including age, pack years of smoking, and alcohol intake as covariates, log-transformed adiponectin was inversely associated with both VAT and SAT when these two obesity measures were included separately in the models. However, log-transformed adiponectin was inversely associated with VAT (standardized β estimate = −0.465; P < 0.0001) and positively associated with SAT (standardized β estimate = 1.277; P = 0.03), when these were included concomitantly in the model. In conclusion, VAT and SAT had differential associations with serum adiponectin concentrations. 相似文献