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71.
Ogino Y Ohtake N Nagae Y Matsuda K Moriya M Suga T Ishikawa M Kanesaka M Mitobe Y Ito J Kanno T Ishihara A Iwaasa H Ohe T Kanatani A Fukami T 《Bioorganic & medicinal chemistry letters》2008,18(18):5010-5014
Design, syntheses, and structure-activity relationships of a novel class of 2-{3-oxospiro[isobenzofuran-1(3H),4'-piperidin]-1'-yl}benzimidazole NPY Y5 receptor antagonists are described. The benzimidazole structures were newly designed based on the urea linkage of our prototype Y5 receptor antagonists (2 and 3). By optimizing substituents on the benzimidazole core part of the lead compound 5a, we were able to develop a potent, orally available, and brain-penetrable Y5 selective antagonist (5k). 相似文献
72.
Kondou Y Higuchi M Takahashi S Sakurai T Ichikawa T Kuroda H Yoshizumi T Tsumoto Y Horii Y Kawashima M Hasegawa Y Kuriyama T Matsui K Kusano M Albinsky D Takahashi H Nakamura Y Suzuki M Sakakibara H Kojima M Akiyama K Kurotani A Seki M Fujita M Enju A Yokotani N Saitou T Ashidate K Fujimoto N Ishikawa Y Mori Y Nanba R Takata K Uno K Sugano S Natsuki J Dubouzet JG Maeda S Ohtake M Mori M Oda K Takatsuji H Hirochika H Matsui M 《The Plant journal : for cell and molecular biology》2009,57(5):883-894
Ectopic gene expression, or the gain-of-function approach, has the advantage that once the function of a gene is known the gene can be transferred to many different plants by transformation. We previously reported a method, called FOX hunting, that involves ectopic expression of Arabidopsis full-length cDNAs in Arabidopsis to systematically generate gain-of-function mutants. This technology is most beneficial for generating a heterologous gene resource for analysis of useful plant gene functions. As an initial model we generated more than 23 000 independent Arabidopsis transgenic lines that expressed rice fl-cDNAs (Rice FOX Arabidopsis lines). The short generation time and rapid and efficient transformation frequency of Arabidopsis enabled the functions of the rice genes to be analyzed rapidly. We screened rice FOX Arabidopsis lines for alterations in morphology, photosynthesis, element accumulation, pigment accumulation, hormone profiles, secondary metabolites, pathogen resistance, salt tolerance, UV signaling, high light tolerance, and heat stress tolerance. Some of the mutant phenotypes displayed by rice FOX Arabidopsis lines resulted from the expression of rice genes that had no homologs in Arabidopsis . This result demonstrated that rice fl-cDNAs could be used to introduce new gene functions in Arabidopsis. Furthermore, these findings showed that rice gene function could be analyzed by employing Arabidopsis as a heterologous host. This technology provides a framework for the analysis of plant gene function in a heterologous host and of plant improvement by using heterologous gene resources. 相似文献
73.
74.
Chad Laing Cody Buchanan Eduardo N Taboada Yongxiang Zhang Andrew Kropinski Andre Villegas James E Thomas Victor PJ Gannon 《BMC bioinformatics》2010,11(1):461
Background
The pan-genome of a bacterial species consists of a core and an accessory gene pool. The accessory genome is thought to be an important source of genetic variability in bacterial populations and is gained through lateral gene transfer, allowing subpopulations of bacteria to better adapt to specific niches. Low-cost and high-throughput sequencing platforms have created an exponential increase in genome sequence data and an opportunity to study the pan-genomes of many bacterial species. In this study, we describe a new online pan-genome sequence analysis program, Panseq. 相似文献75.
Kanbe Y Kim MH Nishimoto M Ohtake Y Yoneya T Ohizumi I Tsunenari T Taniguchi K Kaiho S Nabuchi Y Araya H Kawata S Morikawa K Jo JC Kwon HA Lim HS Kim HY 《Bioorganic & medicinal chemistry letters》2006,16(18):4959-4964
In order to develop orally active pure antiestrogens, we incorporated the carboxy-containing side chains into the 7alpha-position of the steroid scaffold and found that 17-keto derivative CH4893237 (12b) functioned as a pure antiestrogen with its oral activity much superior to clinically used pure antiestrogen, ICI182,780. Results from the pharmacokinetic evaluation indicated that the potent antiestrogen activity at oral dosing in mice attributed to both improved absorption from the intestinal wall and metabolic stability in liver. 相似文献
76.
Novel vasopressin V2 receptor-selective antagonists, pyrrolo[2,1-a]quinoxaline and pyrrolo[2,1-c][1,4]benzodiazepine derivatives. 总被引:1,自引:0,他引:1
Y Ohtake A Naito H Hasegawa K Kawano D Morizono M Taniguchi Y Tanaka H Matsukawa K Naito T Oguma Y Ezure Y Tsuriya 《Bioorganic & medicinal chemistry》1999,7(6):1247-1254
The intent of the work was to study the structure-activity relationships of AVP receptor antagonists bearing a chiral ring as a partial structure since such studies had been reported for only achiral compounds. In the present paper, we deal with compounds consisting of the chiral tricyclic hetero ring (1,2,3,3a,4,5-hexahydropyrrolo[1,2-a]quinoxaline and 1,2,3,10,11,11a-hexahydro-1H-pyrrolo[2,1-c][1,4]benzodiazepine) and 2-phenylbenzanilide analogues. These compounds exhibited a highly selective affinity for V2 receptor, and their stereochemical configuration had a great influence on V2 receptor binding. VP-343 (N-[4-[[(2S,3aR)-2-hydroxy-2,3,3a,4-tetrahydropyrrolo[1,2-a] quinoxalin-5(1H)-yl]carbonyl]phenyl]-4'-methyl[1,1'-biphenyl]-2-ca rboxamide), VP-365 (N-[4-[[(11aS)-2,3,11,11a-tetrahydro-1H-pyrrolo[2,1-c][1,4]benz odiazepin-10(5H)-yl]carbonyl]phenyl][1,1'-biphenyl-2-carboxamide) and VP-339 (N-[4-[[(11aS)-5-oxo-2,3,11,11a-tetrahydro-1H-pyrrolo[2,1-c][1,4]+ ++benzodiazepin-10(5H)-yl]carbonyl]phenyl][1,1'-biphenyl]-2-carboxami de) were the most potent compounds in vitro and in vivo. The IC50 values of VP-343, VP-365 and VP-339 against V2 receptor were 0.772, 1.18 and 0.216 nM, respectively. The ED300 values (dose required to increase three times the urine volume of the control rats; oral administration) of VP-343, VP-365 and VP-339 were 0.22, 0.31 and 0.78 mg/kg, respectively. 相似文献
77.
Ohte S Shin M Sasanuma H Yoneyama K Akita M Ikebuchi K Jimi E Maruki Y Matsuoka M Namba A Tomoda H Okazaki Y Ohtake A Oda H Owan I Yoda T Furuya H Kamizono J Kitoh H Nakashima Y Susami T Haga N Komori T Katagiri T 《Biochemical and biophysical research communications》2011,(1):213-218
Naphthoquinone derivatives have been reported to possess various pharmacological activities, such as antiplatelet, anticancer, antifungal, and antiviral properties. In this study, we investigated the effects of a newly-synthesized naphthoquinone derivative, 2-decylamino-5,8-dimethoxy-1,4-naphthoquinone (2-decylamino-DMNQ), on VSMC proliferation and examined the molecular basis of the underlying mechanism. In a dose-dependent manner, 2-decylamino-DMNQ inhibited PDGF-stimulated VSMC proliferation with no apparent cytotoxic effect. While 2-decylamino-DMNQ did not affect PDGF-Rβ or Akt, it did inhibit the phosphorylation of Erk1/2 and PLCγ1 induced by PDGF. Moreover, 2-decylamino-DMNQ suppressed DNA synthesis through the arrest of cell cycle progression at the G0/G1 phase, including the suppression of pRb phosphorylation and a decrease in PCNA expression, which was related to the downregulation of cell cycle regulatory factors, such as cyclin D1/E and CDK 2/4. It was demonstrated that both U0126, an Erk1/2 inhibitor, and U73122, a PLCγ inhibitor, increased the proportion of cells in the G0/G1 phase of the cell cycle. Thus, these results suggest that 2-decylamino DMNQ has an inhibitory effect on PDGF-induced VSMC proliferation and the mechanism of this action is through cell cycle arrest at the G0/G1 phase. This may be a useful tool for studying interventions for vascular restenosis in coronary revascularization procedures and stent implantation. 相似文献
78.
Honda K Okamoto K Mochida Y Ishioka K Oka M Maesato K Ikee R Moriya H Hidaka S Ohtake T Doi K Fujita T Kobayashi S Noiri E 《American journal of physiology. Cell physiology》2011,301(6):C1423-C1430
Maggot debridement therapy (MDT) is effective for treating intractable wounds, but its precise molecular mechanism, including the association between MDT and growth factors, remains unknown. We administered MDT to nine patients (66.3 ± 11.8 yr, 5 male and 4 female) with intractable wounds of lower extremities because they did not respond to conventional therapies. Significant increases of hepatocyte growth factor (HGF) levels were observed in femoral vein blood during 48 h of MDT (P < 0.05), but no significant change was found for vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), transforming growth factor-β1 (TGF-β1), or tumor necrosis factor-α (TNF-α). We conducted NIH-3T3 cell stimulation assay to evaluate the relation between HGF and protease activity in excretion/secretion (ES) derived from maggots. Compared with the control group, HGF was significantly higher in the 0.05 μg/ml ES group (P < 0.01). Furthermore, protease inhibitors suppressed the increase of HGF (P < 0.05). The HGF expression was increased in proportion to the ES protein concentration of 0.025 to 0.5 μg/ml. In fact, ES showed stronger capability of promoting HGF production and less cytotoxicity than chymotrypsin or bromelain. HGF is an important factor involved in cutaneous wound healing. Therefore, these results suggest that formation of healthy granulation tissue observed during MDT results from the increased HGF. Further investigation to identify molecules enhancing HGF expression by MDT will contribute greatly to drug target discovery for intractable wound healing therapy. 相似文献
79.
Hirose M Egashira S Goto Y Hashihayata T Ohtake N Iwaasa H Hata M Fukami T Kanatani A Yamada K 《Bioorganic & medicinal chemistry letters》2003,13(24):4497-4499
The identification of potent and selective orexin-2 receptor (OX2R) antagonists is described based on the modification of N-acyl 6,7-dimethoxy-1,2,3,4-tetrahydroisoquinoline analogue 1, recently discovered during high throughput screening (HTS). Substitution of an acyl group in 1 with tert-Leucine (tert-Leu), and introduction of a 4-pyridylmethyl substituent onto the amino function of tert-Leu improved compound potency, selectivity, and water solubility. Thus, compound 29 is a promising tool to investigate the role of orexin-2 receptors. 相似文献
80.
Ogino Y Ohtake N Kobayashi K Kimura T Fujikawa T Hasegawa T Noguchi K Mase T 《Bioorganic & medicinal chemistry letters》2003,13(13):2167-2172
Optimization of the amine part of our original muscarinic M(3) receptor antagonist 1 was performed to identify M(3) receptor antagonists that are superior to 1. Compounds carrying a variety of diamine moieties without hydrophobic substituent on the nitrogen atom were screened against the binding affinity for the M(3) receptor and the selectivity for M(3) over the M(1) and M(2) receptors. This process led to a 4-aminopiperidinamide (2l) with a K(i) value of 5.1 nM and with a selectivity of the M(3) receptor that was 46-fold greater than that of the M(2) receptor. Further derivatization of 2l by inserting a spacer group or by incorporating alkyl group(s) into the amine part resulted in the identification of an 4-(aminoethyl)piperidinamide 2l-b with a K(i) value of 3.7 nM for the M(3) receptor and a selectivity for the M(3) receptor that was 170-fold greater than that of the M(2) receptor. 相似文献