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941.
Jürgen Geisler Takashi Suzuki Hildegunn Helle Yasuhiro Miki Shuji Nagasaki Nhat K. Duong Dagfinn Ekse Turid Aas Dean B. Evans Per E. Lønning Hironobu Sasano 《The Journal of steroid biochemistry and molecular biology》2010,118(4-5):237-241
Breast cancer tissue estrogen levels on an average exceed plasma as well as benign breast tissue levels. To evaluate the contribution of intra-tumor aromatization to individual tumor estrogen levels (estradiol, E2; estrone, E1; estrone sulfate, E1S), breast cancer tissue sections obtained during mastectomy in 28 postmenopausal breast cancer patients were stained for aromatase protein expression using the aromatase antibody 677. The findings were correlated to intra-tumor estrogen levels determined with a highly sensitive HPLC-RIA. Staining with 677 alone (irrespective of the hormone receptor status) revealed no difference in tumor E2 levels comparing 677+ versus 677? tumors, although a non-significant trend towards higher tumor E1 and E1S levels was observed in 677+ breast cancers. In contrast, tumor levels of E2 were significantly higher in ER+ tumors compared to ER? tumors (P < 0.001) and to benign breast tissue from the same breast (P < 0.001). Analysing the additional effect of positive staining with the aromatase antibody 677 on tumor estrogen levels in the subgroup of ER+ tumors, revealed significantly higher tumor levels of E2 (mean level of 544.7 versus 197.1 fmol/g tissue) as well as a non-significant trend concerning tumor E1 (mean level of 296.9 versus 102.1 fmol/g tissue). The mean tumor tissue E1S level was observed somewhat lower in ER+677+ (103.5 fmol/g) versus ER+677? tumors (190.1 fmol/g). In the subgroup of ER+PgR+ tumors, tissue levels of E2 were also found to be significantly higher among 677+ compared to 677? tumors: 873.2 fmol/g (95% CI 395.9–1925.6) versus 217.9 fmol/g (95% CI 88.8–534.9) (P = 0.015).In conclusion, our results indicate a moderate effect of aromatase enzyme expression evaluated by IHC using the antibody 677 on intra-tumor estrogen levels among ER+ breast cancers. A substantial interindividual variation in the ratios between the individual estrogen fractions suggests additional effects, like alterations in other enzymes to be involved in the intra-tumor estrogen homeostasis. 相似文献
942.
Takashi L. Shimada Tomoo Shimada Ikuko Hara‐Nishimura 《The Plant journal : for cell and molecular biology》2010,61(3):519-528
The creation of transgenic plants has contributed extensively to the advancement of plant science. Establishing homozygous transgenic lines is time‐consuming and laborious, and using antibiotics or herbicides to select transformed plants may adversely affect the growth of some transgenic plants. Here we describe a novel technology, which we have named FAST (fluorescence‐accumulating seed technology), that overcomes these difficulties. Although this technology was designed for use in Arabidopsis thaliana, it may be adapted for use in other plants. The technology is based on the expression of a fluorescent co‐dominant screenable marker FAST, under the control of a seed‐specific promoter, on the oil body membrane. The FAST marker harbors a fusion gene encoding either GFP or RFP with an oil body membrane protein that is prominent in seeds. The marker protein was only expressed in a specific organ (i.e. in dry seeds) and at a specific time (i.e. during dormancy), which are desirable features of selectable and/or screenable markers. This technique provides an immediate and non‐destructive method for identifying transformed dry seeds. It identified the heterozygous transformed seeds among the T1 population and the homozygous seeds among the T2 population with a false‐discovery rate of <1%. The FAST marker reduces the length of time required to produce homozygous transgenic lines from 7.5 to 4 months. Furthermore, it does not require sterilization, clean‐bench protocols or the handling of large numbers of plants. This technology should greatly facilitate the generation of transgenic Arabidopsis plants. 相似文献
943.
Nobuhisa Ozaki Arigala Uma Ravi Sankar Mitsuji Yamashita Takashi Aoki Yasutaka Tanaka Motohiko Kimura Mitsuo Toda Michio Fujie Yasuo Takehara Harumi Sakahara 《Bioorganic & medicinal chemistry letters》2010,20(3):932-934
A new type of dendritic molecules Gd-DTPA-XDA-D1-Glc(OH), which work as a functionalized ligand coordinating gadolinium(III) ion at the center of their frameworks with two glucose moieties on the molecular surfaces, were readily synthesized with high yield. The structures were established by IR, 1H, 13C NMR, and mass spectral studies. Its bio-distribution patterns were evaluated on rats. 相似文献
944.
Hirotoshi Urakawa Keiichi Yamada Keiko Komagoe Setsuko Ando Hiroyuki Oku Takashi Katsu Ichiro Matsuo 《Bioorganic & medicinal chemistry letters》2010,20(5):1771-1775
A series of cationic cyclic heptapeptides based on polymyxin B have been synthesized for use as permeabilizers of the outer membrane of Gram-negative bacteria. Only analogs with the Dab2-d-Phe3-Leu4-Xxx5 sequence (Xxx = Dab or Orn) showed a synergistic bactericidal effect when combined with conventional antibiotics, indicating that the Dab2 residue plays a critical role in permeation of the outer membrane of Gram-negative bacteria. 相似文献
945.
Yusuke Hirasawa Tomokazu Shoji Takashi Arai Alfarius E. Nugroho Jun Deguchi Takahiro Hosoya Nahoko Uchiyama Yukihiro Goda Khalijah Awang A. Hamid A. Hadi Motoo Shiro Hiroshi Morita 《Bioorganic & medicinal chemistry letters》2010,20(6):2021-2024
A new bisindole alkaloid, bisleuconothine A (1) consisting of an eburnane–aspidosperma type skeleton, was isolated from the bark of Leuconotis griffithii. The structure including absolute stereochemistry was elucidated on the basis of 2D NMR data and X-ray analysis. Bisleuconothine A (1) showed cell growth inhibitory activity against various human cancer cell lines. 相似文献
946.
Siew Leong Chan Takashi Mukasa Eugenio Santelli Lieh Yoon Low Jaime Pascual 《Protein science : a publication of the Protein Society》2010,19(1):155-161
Plants use a highly evolved immune system to exhibit defense response against microbial infections. The plant TIR domain, together with the nucleotide‐binding (NB) domain and/or a LRR region, forms a type of molecule, named resistance (R) proteins, that interact with microbial effector proteins and elicit hypersensitive responses against infection. Here, we report the first crystal structure of a plant TIR domain from Arabidopsis thaliana (AtTIR) solved at a resolution of 2.0 Å. The structure consists of five β‐strands forming a parallel β‐sheet at the core of the protein. The β‐strands are connected by a series of α‐helices and the overall fold mimics closely that of other mammalian and bacterial TIR domains. However, the region of the αD‐helix reveals significant differences when compared with other TIR structures, especially the αD3‐helix that corresponds to an insertion only present in plant TIR domains. Available mutagenesis data suggest that several conserved and exposed residues in this region are involved in the plant TIR signaling function. 相似文献
947.
Slater L Bartlett NW Haas JJ Zhu J Message SD Walton RP Sykes A Dahdaleh S Clarke DL Belvisi MG Kon OM Fujita T Jeffery PK Johnston SL Edwards MR 《PLoS pathogens》2010,6(11):e1001178
The relative roles of the endosomal TLR3/7/8 versus the intracellular RNA helicases RIG-I and MDA5 in viral infection is much debated. We investigated the roles of each pattern recognition receptor in rhinovirus infection using primary bronchial epithelial cells. TLR3 was constitutively expressed; however, RIG-I and MDA5 were inducible by 8-12 h following rhinovirus infection. Bronchial epithelial tissue from normal volunteers challenged with rhinovirus in vivo exhibited low levels of RIG-I and MDA5 that were increased at day 4 post infection. Inhibition of TLR3, RIG-I and MDA5 by siRNA reduced innate cytokine mRNA, and increased rhinovirus replication. Inhibition of TLR3 and TRIF using siRNA reduced rhinovirus induced RNA helicases. Furthermore, IFNAR1 deficient mice exhibited RIG-I and MDA5 induction early during RV1B infection in an interferon independent manner. Hence anti-viral defense within bronchial epithelium requires co-ordinated recognition of rhinovirus infection, initially via TLR3/TRIF and later via inducible RNA helicases. 相似文献
948.
Ad N Cheng DC Martin J Berglin EE Chang BC Doukas G Gammie JS Nitta T Wolf RK Puskas JD 《Innovations (Philadelphia, Pa.)》2010,5(2):74-83
OBJECTIVE:: This purpose of this consensus conference was to determine whether surgical atrial fibrillation (AF) ablation during cardiac surgery improves clinical and resource outcomes compared with cardiac surgery alone in adults undergoing cardiac surgery for valve or coronary artery bypass grafting. METHODS:: Before the consensus conference, the consensus panel reviewed the best available evidence, whereby systematic reviews, randomized trials, and nonrandomized trials were considered in descending order of validity and importance. Evidence-based statements were created, and consensus processes were used to determine the ensuing recommendations. The American Heart Association/American College of Cardiology system was used to label the level of evidence and class of recommendation. RESULTS:: The consensus panel agreed on the following statements in patients with AF undergoing cardiac surgery concomitant surgical ablation: CONCLUSIONS:: Given these evidence-based statements, the consensus panel stated that, in patients with persistent and permanent AF undergoing cardiac surgery, concomitant surgical ablation is recommended to increase incidence of sinus rhythm at short- and long-term follow-up (class 1, level A); to reduce the risk of stroke and thromboembolic events (class 2a, level B); to improve EF (class 2a, level A); and to exercise tolerance (class 2a, level A) and long-term survival (class 2a, level B). 相似文献
949.
Savitree Limtong Rungluk Kaewwichian Somjit Am-In Chanita Boonmak Sasitorn Jindamorakot Wichien Yongmanitchai Natana Srisuk Hiroko Kawasaki & Takashi Nakase 《FEMS yeast research》2010,10(1):114-122
Nine strains of three novel anamorphic yeast species were obtained from samples collected in Thailand including six strains (RV96, RV152, R14, RS9, RS58 and EA1) obtained from estuarine waters collected from two mangrove forests, one strain (ST84) from insect frass and two strains (SR16 and UB13) from forest soils. On the basis of morphological, biochemical, physiological and chemotaxonomic characteristics, and the sequence analysis of the D1/D2 domain of the large subunit rRNA gene, the nine strains were found to represent three novel Candida species in the Saturnispora clade. Five strains (RV96, RV152, R14, RS9 and RS58) were assigned as a single novel species, which was named Candida sanitii sp. nov. The type strain is RV152T (BCC 25967T =NBRC 103864T =CBS 10864T ). Strain EA1 was named as Candida suwanaritii sp. nov. The type strain is EA1T (BCC 29900T =NBRC 104877T =CBS 11021T ). Three strains (ST84, SR16 and UB13) represented another novel species, for which Candida sekii sp. nov. is proposed. The type strain is ST84T (BCC 8320T =NBRC 105671T =CBS 10931T ). 相似文献
950.
Akihisa Suzuki Akiko Horiuchi Takashi Ashida Tsutomu Miyamoto Hiroyasu Kashima Toshio Nikaido Ikuo Konishi Tanri Shiozawa 《Journal of cellular and molecular medicine》2010,14(9):2305-2317
Although overexpression of cyclin A2 is reportedly an indicator of a poor prognosis of various malignancies including endometrial carcinoma, its molecular mechanism remains undetermined. To address this issue, we examined the effect of cyclin A2 on the development of resistance to chemotherapeutic drugs. The expression of cyclin A2 protein was increased in advanced‐stage and chemotherapy‐refractory stage endometrial carcinomas compared with that in early‐stage tumours. The expression levels of cyclin A2 in endometrial carcinoma cell lines correlated positively with the IC50 for cisplatin. Endometrial carcinoma HHUA cells that overexpressed cyclin A2 showed increased resistance to cisplatin in vitro and in vivo, via the activation of a survival pathway, the inositol‐3 phosphate kinase (PI3K) cascade. The use of a cDNA microarray identified an Akt‐binding protein, periplakin, as a novel target of cyclin A2. The cyclin A2‐induced up‐regulation of periplakin was mediated via direct binding of Sp1 to the promoter that was activated by cyclin A2 along with chromatin remodelling involving CBP/p300, and the siRNA‐mediated silencing of periplakin suppressed the PI3K pathway. These results indicate cyclin A2 to be involved in the acquisition of aggressive behaviour of tumour cells through the activation of PI3K by cyclin A2‐induced periplakin, and to be a promising therapeutic target. 相似文献