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821.
Tarô Adati Shinichi Kato Wataru Toriumi Kei Kawazu Wayan Susila Ketut Sumiartha Gede Suastika Dadang I Made Samudra 《Applied Entomology and Zoology》2013,48(2):113-118
The efficacy of synthetic female sex pheromone lures for Crocidolomia pavonana (Fabricius) (Lepidoptera: Crambidae) in the cabbage fields of Java and Bali, Indonesia, was investigated by varying the composition and dosage of the components. The lure containing a synthetic pheromone blend of (Z)-11-hexadecenyl acetate (Z11–16: Ac) and (Z)-9-tetradecenyl acetate (Z9–14: Ac) at a 10:1 ratio acquired significantly more male catches than single component lures and the control lure. Meanwhile, no attraction was observed when lures with 1:1 and 1:10 blends were tested. The composition of Z11–16: Ac and Z9–14: Ac at a ratio of 5, 10 and 20:1 attracted more males than the control lures. Dosage studies showed that 0.055 and 0.55 mg of a mixture of Z11–16: Ac and Z9–14: Ac (10:1 ratio) attracted more males than the control. These results are the first demonstration of the efficacy of synthetic pheromone for C. pavonana in field conditions. The present study suggests the feasibility of pheromone-based monitoring as a simple and low-cost technique for integrated pest management of this pest. 相似文献
822.
823.
Masatsugu Toyota Norifumi Ikeda Satoe Sawai‐Toyota Takehide Kato Simon Gilroy Masao Tasaka Miyo Terao Morita 《The Plant journal : for cell and molecular biology》2013,76(4):648-660
The starch‐statolith hypothesis proposes that starch‐filled amyloplasts act as statoliths in plant gravisensing, moving in response to the gravity vector and signaling its direction. However, recent studies suggest that amyloplasts show continuous, complex movements in Arabidopsis shoots, contradicting the idea of a so‐called ‘static’ or ‘settled’ statolith. Here, we show that amyloplast movement underlies shoot gravisensing by using a custom‐designed centrifuge microscope in combination with analysis of gravitropic mutants. The centrifuge microscope revealed that sedimentary movements of amyloplasts under hypergravity conditions are linearly correlated with gravitropic curvature in wild‐type stems. We next analyzed the hypergravity response in the shoot gravitropism 2 (sgr2) mutant, which exhibits neither a shoot gravitropic response nor amyloplast sedimentation at 1 g . sgr2 mutants were able to sense and respond to gravity under 30 g conditions, during which the amyloplasts sedimented. These findings are consistent with amyloplast redistribution resulting from gravity‐driven movements triggering shoot gravisensing. To further support this idea, we examined two additional gravitropic mutants, phosphoglucomutase (pgm) and sgr9, which show abnormal amyloplast distribution and reduced gravitropism at 1 g . We found that the correlation between hypergravity‐induced amyloplast sedimentation and gravitropic curvature of these mutants was identical to that of wild‐type plants. These observations suggest that Arabidopsis shoots have a gravisensing mechanism that linearly converts the number of amyloplasts that settle to the ‘bottom’ of the cell into gravitropic signals. Further, the restoration of the gravitropic response by hypergravity in the gravitropic mutants that we tested indicates that these lines probably have a functional gravisensing mechanism that is not triggered at 1 g . 相似文献
824.
Shuji Yonezawa Hidekuni Yamakawa Chie Muto Motoko Hosono Takahiko Yamamoto Kazunari Hattori Masahiro Sakagami Hiroko Togame Yoshikazu Tanaka Toru Nakano Hiroshi Takemoto Mitsuhiro Arisawa Satoshi Shuto 《Bioorganic & medicinal chemistry letters》2013,23(10):2912-2915
To improve the efficacy of the conformationally restricted BACE1 inhibitors, structural modifications were investigated using two strategies: (a) modification of the terminal aromatic ring and (b) insertion of a spacer between the aromatic rings. In the latter approach, another type of inhibitor 17 bearing an ethylene spacer between two aromatic rings was found to exhibit good BACE1 inhibitory activity, while the corresponding conformationally unrestricted compound 25 showed no activity. This result revealed an interesting effect of a conformational restriction with a cyclopropane ring. 相似文献
825.
Shinnosuke Machida Mai Tsubamoto Nobuo Kato Kazuo Harada Junko Ohkanda 《Bioorganic & medicinal chemistry》2013,21(14):4004-4010
Bivalent enzyme inhibitors, in which a surface binding module is linked to an active site binding module through a spacer, are a robust approach for site-selectively delivering a minimally-sized agent to a protein surface to regulate its functions, such as protein–protein interactions (PPIs). Previous research revealed that these agents effectively disrupt the interaction between farnesyltransferase (FTase) and the C-terminal region of K-Ras4B protein. However, the whole cell activity of these peptide-based agents is limited due to their low membrane permeability. In this study, we tested a peptidomimetic modification of these bivalent agents using a previously developed inhibitor, FTI-249, and evaluated their cell permeability and biological activity in cells. Confocal cell imaging using fluorescently-labeled agents showed that the peptidomimetic 3-BODIPY penetrated cells, while the peptide-based 1-BODIPY did not. Cell-based evaluation demonstrated that peptidomimetic 3 at a concentration of 100 μM inhibited HDJ-2 processing in cells, indicating that this peptidomimetic modification improves cell permeability, thus leading to enhanced whole cell activity of the bivalent compounds. 相似文献
826.
Youichi Kawakita Masaki Seto Tomohiro Ohashi Toshiya Tamura Tadashi Yusa Hiroshi Miki Hidehisa Iwata Hidenori Kamiguchi Toshimasa Tanaka Satoshi Sogabe Yoshikazu Ohta Tomoyasu Ishikawa 《Bioorganic & medicinal chemistry》2013,21(8):2250-2261
A novel 7,6 fused bicyclic scaffold, pyrimido[4,5-b]azepine was designed to fit into the ATP binding site of the HER2/EGFR proteins. The synthesis of this scaffold was accomplished by an intramolecular Claisen-type condensation. As the results of optimization lead us to 4-anilino and 6-functional groups, we discovered 6-substituted amide derivative 19b, which has a 1-benzothiophen-4-yloxy group attached to the 4-anilino group. An X-ray co-crystal structure of 19b with EGFR demonstrated that the N-1 and N-3 nitrogens of the pyrimido[4,5-b]azepine scaffold make hydrogen-bonding interactions with the main chain NH of Met793 and the side chain of Thr854 via a water-mediated hydrogen bond network, respectively. In addition, the NH proton at the 9-position makes an additional hydrogen bond with the carbonyl group of Met793, as we expected. Compound 19b revealed potent HER2/EGFR kinase (IC50: 24/36 nM) and BT474 cell growth (GI50: 18 nM) inhibitory activities based on its pseudo-irreversible (PI) profile. 相似文献
827.
Yoshihiro Kato Motoji Kawasaki Tomohiro Nigo Shunya Nakamura Akira Fusano Yasuhiro Teranishi Mari N. Ito Takaaki Sumiyoshi 《Bioorganic & medicinal chemistry》2013,21(18):5851-5854
A series of 2,3-disubstituted pyridines were synthesized and evaluated for their PDE4 inhibitory activity. We successfully modified undesirable cyano group of initial lead compound 2 to 4-pyridyl group with improvement of in vitro efficacy and optimized the position of nitrogen atoms in pyridine moiety and alkylene linker. The most potent compound showed significant efficacy in animal models of asthma and inflammation. 相似文献
828.
829.
Yuji Nakamura Teppei Fujimoto Yasuyuki Ogawa Hidenori Namiki Sayaka Suzuki Masayoshi Asano Chie Sugita Akiyoshi Mochizuki Shojiro Miyazaki Kazuhiko Tamaki Yoko Nagai Shin-ichi Inoue Takahiro Nagayama Mikio Kato Katsuyoshi Chiba Kiyoshi Takasuna Takahide Nishi 《Bioorganic & medicinal chemistry》2013,21(11):3175-3196
With the aim to address an undesired cardiac issue observed with our related compound in the recently disclosed novel series of renin inhibitors, further chemical modifications of this series were performed. Extensive structure–activity relationships studies as well as in vivo cardiac studies using the electrophysiology rat model led to the discovery of clinical candidate trans-adamantan-1-ol analogue 56 (DS-8108b) as a potent renin inhibitor with reduced potential cardiac risk. Oral administration of single doses of 3 and 10 mg/kg of 56 in cynomolgus monkeys pre-treated with furosemide led to significant reduction of mean arterial blood pressure for more than 12 h. 相似文献
830.
Hiroko Kato Kenji Izumi Taro Saito Hisashi Ohnuki Michiko Terada Yoshiro Kawano Kayoko Nozawa-Inoue Chikara Saito Takeyasu Maeda 《Histochemistry and cell biology》2013,139(6):847-862
Aldehyde dehydrogenases (ALDHs), enzymes responsible for detoxification and retinoic acid biosynthesis, are considered a potent functional stem cell marker of normal and malignant cells in many tissues. To date, however, there are no available data on ALDH distributions and functions in oral mucosa. This study aims to clarify the levels and types of ALDH expression using immunohistochemistry with accompanying mRNA expression as well as an ALDEFLUOR assay, and to assess phenotypic and histological changes after manipulation of the ALDH activity of oral keratinocytes to increase the potency of a tissue-engineered oral mucosa by a specific ALDH inhibitor, diethylaminobenzaldehyde (DEAB), together with small interfering RNA of ALDH1A3 and ALDH3A1. Results showed the mRNA and cytoplasmic protein expression of ALDH1A3 and ALDH3A1 to be mostly localized in the upper suprabasal layer although no ALDH1A1 immunoreaction was detected throughout the epithelium. Oral keratinocytes with high ALDH activity exhibited a profile of differentiating cells. By pharmacological inhibition, the phenotypic analysis revealed the proliferating cell-population shifting to a more quiescent state compared with untreated cells. Furthermore, a well-structured epithelial layer showing a normal differentiation pattern and a decrease in Ki-67 immunopositive basal cells was developed by DEAB incubation, suggesting a slower turnover rate efficient to maintain undifferentiated cells. Histological findings of a regenerated oral epithelium by ALDH1A3 siRNA were similar to those when treated with DEAB while ALDH3A1 siRNA eradicated the epithelial regenerative capacity. These observations suggest the effects of phenotypic and morphological alterations by DEAB on oral keratinocytes are mainly consequent to the inhibition of ALDH1A3 activity. 相似文献