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101.
Kaneuchi M Sasaki M Tanaka Y Shiina H Verma M Ebina Y Nomura E Yamamoto R Sakuragi N Dahiya R 《Biochemical and biophysical research communications》2004,316(4):1156-1162
We hypothesize that 14-3-3 sigma gene expression and its regulation by methylation can characterize histological types of primary human epithelial ovarian cancer. To test this hypothesis, ovarian cancer cell lines and 54 ovarian cancer tissue samples were analyzed for expression and methylation of 14-3-3 sigma gene using methylation specific PCR. The results of our experiments demonstrate that 14-3-3 sigma gene was methylated and inactivated in ES-2 ovarian cell line, which was derived from clear cell adenocarcinoma. Treatment of this cell line with demethylating agent 5-aza-2'-deoxycytidine restored the expression of 14-3-3 sigma gene. In human ovarian cancer tissues, the expression of 14-3-3 sigma protein was inactivated in most of the ovarian clear cell carcinoma tissues. Interestingly, 14-3-3 sigma protein expression was positive in significantly higher percentages of serous (89.5%), endometrioid (90%), and mucinous (81.8%) ovarian adenocarcinoma tissues. The ovarian clear cell carcinoma samples with inactivated 14-3-3 sigma protein were highly methylated, suggesting that inactivation of 14-3-3 sigma gene is through DNA methylation. Using direct DNA sequencing, 14-3-3 sigma gene methylation on all the 17 CpG sites was significantly higher in ovarian clear cell carcinoma as compared to other histological types of ovarian cancer (serous, endometrioid, and mucinous). This is the first report suggesting that 14-3-3 sigma gene expression and methylation status can characterize histological features of different types of ovarian cancer. 相似文献
102.
The production of higher alcohols by engineered bacteria has received significant attention. The budding yeast, Saccharomyces cerevisiae, has considerable potential as a producer of higher alcohols because of its capacity to naturally fabricate fusel alcohols, in addition to its robustness and tolerance to low pH. However, because its natural productivity is not significant, we considered a strategy of genetic engineering to increase production of the branched-chain higher alcohol isobutanol, which is involved in valine biosynthesis. Initially, we overexpressed 2-keto acid decarboxylase (KDC) and alcohol dehydrogenase (ADH) in S. cerevisiae to enhance the endogenous activity of the Ehrlich pathway. We then overexpressed Ilv2, which catalyzes the first step in the valine synthetic pathway, and deleted the PDC1 gene encoding a major pyruvate decarboxylase with the intent of altering the abundant ethanol flux via pyruvate. Through these engineering steps, along with modification of culture conditions, the isobutanol titer of S. cerevisiae was elevated 13-fold, from 11 mg/l to 143 mg/l, and the yield was 6.6 mg/g glucose, which is higher than any previously reported value for S. cerevisiae. 相似文献
103.
Yeasts are promising hosts for industrial bio-refinery applications. In yeast cell surface displays, functional proteins, such as cellulases or lipases, are genetically fused to an anchor protein and expressed on the cell surface. Saccharomyces cerevisiae is the most commonly used yeast for cell surface display. Engineered yeasts have been utilized for a variety of applications, such as bioethanol production, chemicals synthesis, adsorption of environmental pollutants, and protein evolution. Here, we summarize recent developments in yeast cell surface display techniques for bio-refinery applications, including methods using hosts such as Pichia pastoris, Yarrowia lipolytica, and S. cerevisiae, focusing on the characteristics of anchor proteins and applications. 相似文献
104.
105.
106.
Nakabayashi Kazuhiko; Ogata Toshihiko; Fujii Michihiko; Takahashi Ei-ichi; Ogino Hideki; Michishita Eriko; Scherer Stephen W.; Tsui Lap-Chee; Ayusawa Dai 《DNA research》1996,3(3):181-183
Mouse A9 cells containing human chromosome 7 tagged with pSV2neowere irradiated with X-rays and fused to A9 cells to isolateG418-resistant clones. From these clones, we selected radiationhybrids that contained 1040 Mb of human DNA apparentlyat a single site of their genome by FISH analysis using humanrepetitive sequences as a probe. Then we made a panel of hybridsthat contained various fragments of the 7q31-q32 region andcover its entire region altogether by PCR with STS markers ofhuman chromosome 7. This panel is useful in chromosome transferexperiments since the dominant selective marker neo gene isattached to human DNA. 相似文献
107.
Eiichiro Nagata Mieko Ogino Kounosuke Iwamoto Yasuhisa Kitagawa Yasuo Iwasaki Fumihito Yoshii Joh-E. Ikeda ALS Consortium Investigators 《PloS one》2016,11(2)
Objective
Bromocriptine mesylate (BRC), a dopamine D2 receptor agonist has been shown to confer neuroprotection, sustained motor function and slowed disease progression in mouse models of amyotrophic lateral sclerosis (ALS) Here we report a first in human trial in ALS.Design
A multicenter, Riluzole add-on, randomized, double-blind, placebo controlled 102-week extension BRC clinical trial.Methods
The trial was conducted between January 2009 and March 2012 on 36 Japanese ALS patients. A 12-week treatment with Riluzole observational period was followed by combined treatment (Riluzole + BRC; n = 29 or Riluzole + placebo; n = 7). The dosing commenced at 1.25 mg/day increasing in steps at two weeks intervals to a maximum of 15 mg/day. The efficacy of BRC was evaluated by comparing BRC and placebo groups upon completion of stepwise dosing at 14 weeks 2 points (1st endpoint) and upon completion or discontinuation of the study (2nd endpoint) of the dosing.Results
Statistics analyses revealed a marginal BRC treatment efficacy with P≦20%to placebo by 1st and 2nd endpoint analysis. In the 1st endpoint analysis, BRC group was significantly effective on the scores of ALSAQ40-communicaton (P = 1.2%), eating and drinking (P = 2.2%), ALSFRS-R total (P = 17.6%), grip strength (P = 19.8%) compared to the placebo group. In the 2nd endpoint analysis, differences between the scores of Limb Norris Scale (P = 18.3%), ALSAQ40-communication (P = 11.9%), eating and drinking (P = 13.6%), and neck forward-bent test (P = 15.4%) of BRC group were detected between the two groups. There was no significant difference between the treatment groups for adverse events or serious drug reactions incidence.Conclusions
BRC sustains motoneuronal function at least in part through BRC treatment. Further analysis involving a Phase 2b or 3 clinical trial is required but BRC currently shows promise for ALS treatment.Trial Registration
UMIN Clinical Trials UMIN000008527 相似文献108.
Estrone sulfate and sulfatase activity in human breast cancer and endometrial cancer 总被引:3,自引:0,他引:3
K Naitoh H Honjo T Yamamoto M Urabe Y Ogino T Yasumura T Nambara 《Journal of steroid biochemistry》1989,33(6):1049-1054
Estrone sulfate (E1-S) in the serum and tissues of patients with breast cancer or endometrial cancer was measured by a direct radioimmunoassay without hydrolysis. The concentration of E1-S in breast cancer tissue was 1.64 +/- 0.28 ng/g wet wt (+/- SE), lower than in surrounding normal breast tissue (4.46 +/- 1.23). Estradiol-17 beta(E2)/E1-S was higher in endometrial cancer tissue than normal endometrial tissue. Estrone sulfatase activity in breast cancer tissue was 0.81 +/- 0.23 nmol/h/mg protein, higher than in surrounding normal breast tissue (0.35 +/- 0.11). These results suggest that E1-S, which is abundant in the peripheral circulation, is hydrolyzed by sulfatase in breast cancer tissue or endometrial cancer tissue and liberates free estrogens, which may stimulate the growth of these malignant tumors. 相似文献
109.
110.
Esashi Yohji; Kuraishi Ritsu; Tanaka Natsuo; Nagayama Takao 《Plant & cell physiology》1983,24(2):267-271
The cotyledons of secondarily dormant cocklebur (Xanthium pennsylvankumWallr.) seeds lacked not only growing potential but also chlorophyll-formingability. These properties developed as the seeds establishedsecondary dormancy during a soaking period. The inability toform chlorophyll in cotyledonary segments was not improved inthe presence of S-amino levulinic acid. But this ability wasgreatly restored by benzyladenine or ethylene treatment, whichis effective in increasing cotyledonary growth. Similarly, theapplication of ethylene together with enriched oxygen and carbondioxide, or subsequent to a KCN treatment, which were the mosteffective means for breaking secondary dormancy, completelyrestored both chlorophyll formation and growing ability of thecotyledons. The depression of the greening-ability in cotyledonsmay be involved in development of secondary dormancy of cockleburseeds in concert with the decline of their growth pontential. (Received September 24, 1982; Accepted December 27, 1982) 相似文献