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71.
Wenxiu Ye Mohammad Anowar Hossain Shintaro Munemasa Yoshimasa Nakamura Izumi C. Mori Yoshiyuki Murata 《Journal of plant physiology》2013
We recently demonstrated that endogenous abscisic acid (ABA) is involved in methyl jasmonate (MeJA)-induced stomatal closure in Arabidopsis thaliana. In this study, we investigated whether endogenous ABA is involved in MeJA-induced reactive oxygen species (ROS) and nitric oxide (NO) production and cytosolic alkalization in guard cells using an ABA-deficient Arabidopsis mutant, aba2-2, and an inhibitor of ABA biosynthesis, fluridon (FLU). The aba2-2 mutation impaired MeJA-induced ROS and NO production. FLU inhibited MeJA-induced ROS production in wild-type guard cells. Pretreatment with 0.1 μM ABA, which does not induce stomatal closure in the wild type, complemented the insensitivity to MeJA of the aba2-2 mutant. However, MeJA induced cytosolic alkalization in both wild-type and aba2-2 guard cells. These results suggest that endogenous ABA is involved in MeJA-induced ROS and NO production but not in MeJA-induced cytosolic alkalization in Arabidopsis guard cells. 相似文献
72.
Shogo Higaki Yutaka Kawakami Yoshiki Eto Etsuro Yamaha Masashi Nagano Seiji Katagiri Tatsuyuki Takada Yoshiyuki Takahashi 《Cryobiology》2013
The aim of this study was to examine the effects of partial removal of yolk and cryoprotectant mixtures on the viability of cryopreserved primordial germ cells (PGCs) and elucidated the differentiation ability of cryopreserved PGCs in zebrafish. First, dechorionated yolk-intact and yolk-depleted (partially yolk removed) embryos, PGCs of which were labeled with green fluorescence protein (GFP), were vitrified after serial exposures to pretreatment solution (PS) and vitrification solution (VS) that contained ethylene glycol (EG), dimethyl sulfoxide (Me2SO) or propylene glycol at 3 and 5 M, respectively. Although partial removal of yolk improved the viability of cryopreserved PGCs, numbers of PGCs with pseudopodial movement were limited (0–2.6 cells/embryo). Next, yolk-depleted embryos were cryopreserved using mixtures of two types of cryoprotectants. The maximum survival rate of PGCs (81%; 9.6 cells/embryo) was obtained from the yolk-depleted embryos vitrified using PS containing 2 M EG + 1 M Me2SO and VS containing 3 M EG + 2 M Me2SO and 56% (5.3 cells/embryo) of PGCs showed pseudopodial movement. Finally, PGCs recovered from yolk-depleted embryos (wild-type) that were vitrified under the optimum condition were transplanted individually into 236 sterilized recipient blastulae (recessive light-colored). Seven recipients matured and generated progeny with characteristics inherited from the PGC donor. In conclusion, the authors confirmed the beneficial effects of partial removal of yolk on the viability of cryopreserved PGCs and that the viability of the PGCs was improved by using PS and VS that contained two types of cryoprotectants, especially PS containing 2 M EG + 1 M Me2SO and VS containing 3 M EG + 2 M Me2SO, and that recovered PGCs retained ability to differentiate into functional gametes. 相似文献
73.
Yoshiyuki Inoue Keiko Nakahara Keisuke Maruyama Yoshiharu Suzuki Yujiro Hayashi Kenji Kangawa Noboru Murakami 《Biochemical and biophysical research communications》2013,430(1):278-283
In the present study using rats, we demonstrated that central and peripheral administration of des-acyl ghrelin induced a decrease in the surface temperature of the back, and an increase in the surface temperature of the tail, although the effect of peripheral administration was less marked than that of central administration. Furthermore, these effects of centrally administered des-acyl ghrelin could not be prevented by pretreatment with [D-Lys3]-GHRP-6 GH secretagogue receptor 1a (GHS-R1a) antagonists. Moreover, these actions of des-acyl ghrelin on body temperature were inhibited by the parasympathetic nerve blocker methylscopolamine but not by the sympathetic nerve blocker timolol. Using immunohistochemistry, we confirmed that des-acyl ghrelin induced an increase of cFos expression in the median preoptic nucleus (MnPO). Additionally, we found that des-acyl ghrelin dilated the aorta and tail artery in vitro. These results indicate that centrally administered des-acyl ghrelin regulates body temperature via the parasympathetic nervous system by activating neurons in the MnPO through interactions with a specific receptor distinct from the GHS-R1a, and that peripherally administered des-acyl ghrelin acts on the central nervous system by passing through the blood–brain barrier, whereas it exerts a direct action on the peripheral vascular system. 相似文献
74.
Takako Aboshi Nobuhiro Shimizu Yuji Nakajima Yoshiyuki Honda Yasumasa Kuwahara Hiroshi Amano Naoki Mori 《Insect biochemistry and molecular biology》2013,43(11):991-996
We report here that Tyrophagus similis and Tyrophagus putrescentiae (Astigmata: Acaridae) have the ability to biosynthesize linoleic acid [(9Z, 12Z)-9, 12-octadecadienoic acid] via a Δ12-desaturation step, although animals in general and vertebrates in particular appear to lack this ability. When the mites were fed on dried yeast enriched with d31-hexadecanoic acid (16:0), d27-octadecadienoic acid (18:2), produced from d31-hexadecanoic acid through elongation and desaturation reactions, was identified as a major fatty acid component of phosphatidylcholines (PCs) and phosphatidylethanolamines (PEs) in the mites. The double bond position of d27-octadecadienoic acid (18:2) of PCs and PEs was determined to be 9 and 12, respectively by dimethyldisulfide (DMDS) derivatization. Furthermore, the GC/MS retention time of methyl 9, 12-octadecadienoate obtained from mite extracts agreed well with those of authentic linoleic acid methyl ester. It is still unclear whether the mites themselves or symbiotic microorganisms are responsible for inserting a double bond into the Δ12 position of octadecanoic acid. However, we present here the unique metabolism of fatty acids in the mites. 相似文献
75.
Isoko Kuriyama Anna Miyazaki Yuko Tsuda Hiromi Yoshida Yoshiyuki Mizushina 《Bioorganic & medicinal chemistry》2013,21(2):403-411
The present study was designed to investigate the anticancer activity of novel nine small peptides (compounds 1–9) derived from TT-232, a somatostatin structural analogue, by analyzing the inhibition of mammalian DNA polymerase (pol) and human cancer cell growth. Among the compounds tested, compounds 3 [tert-butyloxycarbonyl (Boc)-Tyr-Phe-1-naphthylamide], 4 (Boc-Tyr-Ile-1-naphthylamide), 5 (Boc-Tyr-Leu-1-naphthylamide) and 6 (Boc-Tyr-Val-1-naphthylamide) containing tyrosine (Tyr) but no carboxyl groups, selectively inhibited the activity of rat pol β, which is a DNA repair-related pol. Compounds 3–6 strongly inhibited the growth of human colon carcinoma HCT116 p53+/+ cells. The influence of compounds 1–9 on HCT116 p53?/? cell growth was similar to that observed for HCT116 p53+/+ cells. These results suggest that the cancer cell growth suppression induced by these compounds might be related to their inhibition of pol. Compound 4 was the strongest inhibitor of pol β and cancer cell growth among the nine compounds tested. This compound specifically inhibited rat pol β activity, but had no effect on the other 10 mammalian pols investigated. Compound 4 combined with methyl methane sulfonate (MMS) treatment synergistically suppressed HCT116 p53?/? cell growth compared with MMS alone. This compound also induced apoptosis in HCT116 cells with or without p53. From these results, the influence of compound 4, a specific pol β inhibitor, on the relationship between DNA repair and cancer cell growth is discussed. 相似文献
76.
Hirotaka Kashiwagi Yoshiyuki Ono Masateru Ohta Susumu Itoh Fumihiko Ichikawa Suguru Harada Satoshi Takeda Nobuo Sekiguchi Masaki Ishigai Tadakatsu Takahashi 《Bioorganic & medicinal chemistry》2013,21(7):1823-1833
In an extension of our study on gamma hydroxy carboxylic acid analogs, we explored a series of nonsecosteroidal vitamin D receptor (VDR) agonists in which 1,3-diol of 1,25(OH)2D3 had been replaced by aryl acetic acid. These analogs showed very potent activity in vitro compared with 1,25(OH)2D3. An X-ray analysis of 8d showed that the inserted phenyl ring well mimicked the folded methylene linker of the gamma hydroxy carboxylic acid moiety but the carboxylic acid of 8d interacted with VDR in a different manner from gamma hydroxy carboxylic acids. Through our in vivo screening in an osteoporosis rat model using immature rats, we identified a potent active vitamin D3 analog, compound 7e. In mature rats of the same model, compound 7e also showed good PK profiling and excellent ability to prevent bone mineral density loss without severe hypercalcemia. Our nonsecosteroidal VDR agonist 7e (CH5036249) could be a possible new drug candidate for treating osteoporosis in human. 相似文献
77.
Masaki Setoguchi Shin Iimura Yuuichi Sugimoto Yoshiyuki Yoneda Jun Chiba Toshiyuki Watanabe Fumihito Muro Yutaka Iigo Gensuke Takayama Mika Yokoyama Tomoe Taira Misato Aonuma Tohru Takashi Atsushi Nakayama Nobuo Machinaga 《Bioorganic & medicinal chemistry》2013,21(1):42-61
We have carried out the optimization of substituents at the C-3 or the C-5 position on the pyrrolidine ring of VLA-4 antagonist 3 with 2-(phenylamino)-7-fluorobenzoxazolyl moiety for the purpose of improving in vivo efficacy while maintaining good aqueous solubility. As a result, we successfully increased in vitro activity in the presence of 3% human serum albumin and achieved an exquisite lipophilic and hydrophilic balance of compounds suitable for oral administrative regimen. The modification resulted in the identification of zwitterionic compound 7n with (5S)-[methoxy(methyl)amino]methylpyrrolidine, which significantly alleviated bronchial hyper-responsiveness to acetylcholine chloride at 12.5 mg/kg, p.o. in a murine asthma model and showed favorable aqueous solubility (JP1, 89 μg/mL; JP2, 462 μg/mL). Furthermore, this compound showed good oral bioavailability (F = 54%) in monkeys. 相似文献
78.
Yoshiyuki Hari Takashi Osawa Yutaro Kotobuki Aiko Yahara Ajaya R. Shrestha Satoshi Obika 《Bioorganic & medicinal chemistry》2013,21(14):4405-4412
Artificial thymidine monomers possessing amide or N-methylamide bridges were designed, synthesized, and introduced into oligonucleotides. UV-melting experiments showed that these oligonucleotides preferred single-stranded RNA (ssRNA) to single-stranded DNA (ssDNA) in duplex formation. Both amide- and N-methylamide-modified oligonucleotides led to a significant increase in the binding affinity to ssRNA by up to +4.7 and +3.7 °C of the Tm value per modification, respectively, compared with natural oligonucleotide. In addition, their oligonucleotides showed high stability against 3′-exonuclease. 相似文献
79.
Yoshiyuki Takasaki 《Bioscience, biotechnology, and biochemistry》2013,77(8):1523-1530
A β-amylase and a pullulanase produced by Bacillus cereus var. mycoides were purified by means of ammonium sulfate fractionation, adsorption on starch and celite and Sephadex G–100 column chromatography. The purified enzymes were homogeneous in disc electrophoresis.The β-amylase released only maltose from amylose, amylopectin, starch and glycogen, and the released maltose was in β-form. The pullulanase released maltose, maltotriose and maltotetraose from β-limit dextrin and maltotriose from pullulan, but not amylose-like substance from amylopectin.The optimum pHs of β-amylase and pullulanase were about 7 and 6~6.5, respectively. The optimum temperatures of the enzymes were about 50°C. The enzymes were inhibited by the sulfhydryl reagents such as mercuric chloride and p-chloromercuribenzoate, and the inhibitions with p-chloromercuribenzoate were restored by the addition of cysteine. The molecular weights of β-amylase and pullulanase were estimated to be 35,000±5,000 and 110,000±20,000, respectively. 相似文献
80.
Norio Kurihara Yuzuru Sanemitsu Tomio Kimura Masaharu Kobayashi Minoru Nakajima Yoshiyuki Tamura 《Bioscience, biotechnology, and biochemistry》2013,77(5):784-797
β-BTC(3, 4/5, 6),1) γ-BTC(3, 4, 6/5), and ε-BTC(3, 4, 5/6) were synthesized from α-BTC (3, 6/4, 5) by stepwise routes. 相似文献