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971.
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
972.
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
973.
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
974.
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
975.
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
976.
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
977.
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
978.
Takashi Suzuki Koko Moriya Kei Nagatoshi Yoshinobu Ota Toru Ezure Eiji Ando Susumu Tsunasawa Toshihiko Utsumi 《Proteomics》2010,10(9):1780-1793
To establish a strategy for the comprehensive identification of human N‐myristoylated proteins, the susceptibility of human cDNA clones to protein N‐myristoylation was evaluated by metabolic labeling and MS analyses of proteins expressed in an insect cell‐free protein synthesis system. One‐hundred‐and‐forty‐one cDNA clones with N‐terminal Met‐Gly motifs were selected as potential candidates from ~2000 Kazusa ORFeome project human cDNA clones, and their susceptibility to protein N‐myristoylation was evaluated using fusion proteins, in which the N‐terminal ten amino acid residues were fused to an epitope‐tagged model protein. As a result, the products of 29 out of 141 cDNA clones were found to be effectively N‐myristoylated. The metabolic labeling experiments both in an insect cell‐free protein synthesis system and in the transfected COS‐1 cells using full‐length cDNA revealed that 27 out of 29 proteins were in fact N‐myristoylated. Database searches with these 27 cDNA clones revealed that 18 out of 27 proteins are novel N‐myristoylated proteins that have not been reported previously to be N‐myristoylated, indicating that this strategy is useful for the comprehensive identification of human N‐myristoylated proteins from human cDNA resources. 相似文献
979.
Eiji Yamamoto Tomonori Takashi Yoichi Morinaka Shaoyang Lin Jianzhong Wu Takashi Matsumoto Hidemi Kitano Makoto Matsuoka Motoyuki Ashikari 《Molecular genetics and genomics : MGG》2010,283(4):305-315
Reproductive isolation plays an important role in speciation as it restricts gene flow and accelerates genetic divergence
between formerly interbreeding population. In rice, hybrid breakdown is a common reproductive isolation observed in both intra
and inter-specific crosses. It is a type of post-zygotic reproductive isolation in which sterility and weakness are manifested
in the F2 and later generations. In this study, the physiological and molecular basis of hybrid breakdown caused by two recessive genes,
hbd2 and hbd3, in a cross between japonica variety, Koshihikari, and indica variety, Habataki, were investigated. Fine mapping of hbd2 resulted in the identification of the causal gene as casein kinase I (CKI1). Further analysis revealed that hbd2-CKI1 allele gains its deleterious function that causes the weakness phenotype by a change of one amino acid. As for the other
gene, hbd3 was mapped to the NBS-LRR gene cluster region. It is the most common class of R-gene that triggers the immune signal in response to pathogen attack. Expression analysis of pathogen response marker genes
suggested that weakness phenotype in this hybrid breakdown can be attributed to an autoimmune response. So far, this is the
first evidence linking autoimmune response to post-zygotic isolation in rice. This finding provides a new insight in understanding
the molecular and evolutionary mechanisms establishing post-zygotic isolation in plants. 相似文献
980.
The size and weight of an actuator tend to increase with actuator power because the actuator power-to-mass ratio is near constant for a given type of motor. Rapid motion such as jumping or running is difficult to realize by using simple actuator power. The aim of this research is to develop a high power joint mechanism that mimics the leg mechanism of a locust. The characteristics of the joint mechanism are evaluated using vector and dynamic analysis.The proposed high power joint mechanism consists of a closed link structure comprising four links and a spring. Linear actuators are attached to the top and bottom links, and the joint angle changes by controlling the lengths of the top and bottom links. A spring is located between two of the links, and is contracted using two linear actuators to provide stored force, which can be released instantaneously to produce a higher power response than that available directly from both actuators.The analysis demonstrates how the joint mechanism produces an output with a higher power than the rated input actuator power. The output characteristics of the joint mechanism depend on link length and link conditions. 相似文献