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61.
Hideo Ohashi Tetsuya Kyogoku Takahiro Ishikawa Shin-ichiro Kawase Shingo Kawai 《Journal of Wood Science》1999,45(1):53-63
The present work was undertaken from the standpoint of radical-capturing ability with regard to the antioxidative ability of flavonoids, especially flavonols distributed widely in woody plants. In regard to the flavonols, six methyl derivatives were initially prepared from quercetin and its litinoside. Their radical-capturing constants were determined strictly by the stopped-flow spectroscopic method. It was proved that the radical-capturing ability of quercetin mainly involves the vicinal C3. and C4, hydroxyl groups and the C3 hydroxyl group. To clarify the reaction mechanism begun at the C3 hydroxyl group of quercetin, 5,7,3,4-tetramethylquercetin (TMQ), flavon-3-ol (F30) and so on were treated with 2,2-azo-bis-(2,4-dimethylvaleronitrile) (AMVN). Six products (1–6) containing one depside and its two hydrolytic products, two valeronitrile adducts, and others were isolated from the reaction mixture of TMQ and their structures determined by instrumental analyses. Similarly, F30 gave four products, 7–10, which corresponded to the above products 1–3 and 5 (one depside, its two hydrolytic products, and one adduct), respectively. 3,5,7,3,4-Pentamethylquercetin (PMQ) and flavon-3-O-methylate (F3M) gave no products. The quantitative change of the products with reaction time was determined spectroscopically. An initial reaction pathway for the radical-capturing reaction of flavon-3-ols with AMVN was proposed based on the products and their amounts. The main route — formation of depside and its hydrolytic products via ketohydroperoxide (3) or ketohydroperoxy radical (4) - was similar to that of the oxidation reaction of quercetin with quercetinase and light.Part of this paper was presented at the 46th and 47th annual meetings of the Japan Wood Research Society, Kumamoto and Kouchi, April 1996 and 1997 相似文献
62.
Yoshinori Tokuoka Kentaro Ohigashi Koji Watanabe Hiroshi Yamaguchi Takahiro Ara Nobukazu Nakagoshi 《林业研究》2016,27(6):1287-1294
Natural forest recovery on abandoned farmland is hindered by a variety of factors and active restoration plays an important role when quick afforestation is desired. We investigated seedling survival of four transplanted native tree species (Quercus myrsinifolia, Quercus serrata, Aphananthe aspera, and Rhus sylvestris) by experimentally manipulating the vegetation cover, which was mainly dominated by dwarf bamboo (Pleioblastus chino), and herbivore access to the planting sites on farmland that had been abandoned for 15 years at the start of the study. Few transplanted seedlings of any species survived under intact vegetation cover, irrespective of herbivore presence. In gaps in the vegetation cover, winter browsing by Japanese hare (Lepus brachyurus) damaged all species. However, lower browsing frequency and higher resprouting ability after grazing of the seedlings enabled both Quercus species to survive better than the other species. These results indicate that dwarf bamboo and the hare jointly limit the establishment of native trees in old fields. If active afforestation by transplanting seedlings at sites dominated by dwarf bamboo is planned, a combination of vegetation removal, selection of suitable species, and temporary seedling protection will be most effective. 相似文献
63.
Flonicamid (IKI220; N-cyanomethyl-4-trifluoromethylnicotinamide), a pyridinecarboxamide compound, is a novel systemic insecticide with selective activity against hemipterous pests, such as aphids and whiteflies, and thysanopterous pests. The purpose of this study is to clarify the biological properties of flonicamid against aphids. Flonicamid is very active against aphids, regardless of differences in species, stages and morphs. This compound inhibited the feeding behaviour of aphids within 0.5 h of treatment without noticeable poisoning symptoms such as convulsion, and this antifeeding activity was not recoverable until death. The nymphs born from adults exposed to flonicamid for 3 h showed high mortality. The effect of flonicamid on the feeding activity of an individual aphid was studied using electronic monitoring of insect feeding behaviour (EMIF). Although the treated aphid attached the head of its proboscis to the leaf surface, salivation and sap feeding were strongly inhibited. These results suggest that the main insecticidal mechanism of flonicamid is starvation based on the inhibition of stylet penetration to plant tissues. 相似文献
64.
Two novel dicarboxylic Acid derivatives and a new dimeric hydrolyzable tannin from walnuts 总被引:1,自引:0,他引:1
Ito H Okuda T Fukuda T Hatano T Yoshida T 《Journal of agricultural and food chemistry》2007,55(3):672-679
In addition to the 16 previously reported polyphenols including 3 new ellagitannins, 2 novel dicarboxylic acid derivatives, glansreginins A (1) and B (2), and a new dimeric hydrolyzable tannin, glansrin D (3), were isolated, together with 15 known compounds from walnuts, the seeds of Juglans regia. The structures of the new compounds were elucidated on the basis of 1D- and 2D-NMR analyses and chemical data. The antioxidant effect of these isolates was also evaluated by SOD-like and DPPH radical scavenging activities. 相似文献
65.
Nagai Y Watanabe K Aso H Ohwada S Muneta Y Yamaguchi T 《Domestic animal endocrinology》2006,30(2):144-154
Pro-inflammatory cytokine interleukin 18 (IL-18) has been proposed to have a role in modulating immuno-endocrine functions. Our previous study showed that IL-18 and IL-18 receptor (IL-18R) colocalized in somatotrophs of the bovine anterior pituitary gland, and the possibility that IL-18 acts on somatotrophs as an autocrine factor. In the present study, we investigated the localization of IL-18 and IL-18R in the pig anterior pituitary gland. RT-PCR analysis showed the expression of IL-18 and IL-18R mRNAin the pig anterior pituitary gland. Immunohistochemistry of IL-18 and specific hormones revealed the presence of IL-18 in somatotrophs, mammotrophs, thyrotrophs and gonadotrophs. IL-18R was localized in somatotrophs and thyrotrophs. Furthermore, the somatotrophs immunoreactive for IL-18 did not contain IL-18R. Thus, IL-18R and IL-18 were not colocalized in an identical somatotroph. These findings suggest that the localization of IL-18 in pig somatotrophs is different from that in bovine somatotrophs, although IL-18 closely associates with somatotrophs in the anterior pituitary glands in both species. 相似文献
66.
Tohno M Shimosato T Moue M Aso H Watanabe K Kawai Y Yamaguchi T Saito T Kitazawa H 《Veterinary research》2006,37(6):791-812
To clarify the crucial role of Toll-like receptor (TLR) 2 and TLR9 in immature gut-associated lymphoid tissues (GALT), we focused on the expression of TLR2 and TLR9 and the immune responses induced by their ligands in the GALT of presuckling newborn swine. Quantitative real-time PCR revealed that TLR2 and TLR9 mRNA were expressed at detectable levels in all tested tissues (heart, thymus, lung, spleen, liver, kidney, skeletal muscle, duodenum, jejunum, ileum, ileal Peyer patches (Pps), and mesenteric lymph nodes (MLN)). In particular, in immature intestinal tissues and GALT, TLR2 and TLR9 mRNA were expressed at higher levels in ileal Pps and MLN than in the duodenum, jejunum, and ileum. We confirmed that the TLR2 and TLR9 proteins were also highly expressed and that their ligands were preferentially recognized by TLR2- or TLR9-expressing cells in the MLN and ileal Pps. Zymosan, CpG2006, and lactic acid bacteria could promote mitogenesis and production of multiple cytokines by the MLN and ileal Pps. In addition, double immunostaining for cytokeratin 18 and either TLR2 or TLR9 revealed that both TLR2 and TLR9 are strongly expressed in the columnar membranous (M) cells. Interestingly, while the apical membrane of the columnar M cells strongly expressed TLR2 protein and preferentially recognized zymosan, both "TLR2 expression on the apical membrane" and "TLR2-mediated zymosan binding" were negligible in neighboring enterocytes. These results indicate that TLR2 and TLR9 allow MLN and ileal Pps to respond to a variety of bacterial components immediately after birth, thereby providing newborns with a host defense system. 相似文献
67.
Of the Capsicum peppers (Capsicum spp.), cultivated C. annuum is the most commercially important, but has lacked an intraspecific linkage map based on sequence-specific PCR markers in accord with haploid chromosome numbers. We constructed a linkage map of pepper using a doubled haploid (DH) population derived from a cross between two C. annuum genotypes, a bell-type cultivar ‘California Wonder’ and a Malaysian small-fruited cultivar ‘LS2341 ()’, which is used as a source of resistance to bacterial wilt (Ralstonia solanacearum). A set of 253 markers (151 SSRs, 90 AFLPs, 10 CAPSs and 2 sequence-tagged sites) was on the map which we constructed, spanning 1,336 cM. This is the first SSR-based map to consist of 12 linkage groups, corresponding to the haploid chromosome number in an intraspecific cross of C. annuum. As this map has a lot of PCR-based anchor markers, it is easy to compare it to other pepper genetic maps. Therefore, this map and the newly developed markers will be useful for cultivated C. annuum breeding. JP187992相似文献
68.
69.
Takeda K Tasai M Iwamoto M Oe M Chikuni K Nakamura Y Tagami T Nirasawa K Hanada H Pinkert CA Onishi A 《The Journal of reproduction and development》2012,58(2):248-253
Somatic cell nuclear transfer (SCNT) has been exploited in efforts to clone and propagate valuable animal lineages. However, in many instances, recipient oocytes are obtained from sources independent of donor cell populations. As such, influences of potential nuclear-cytoplasmic incompatibility, post SCNT, are largely unknown. In the present study, alterations in mitochondrial protein levels were investigated in adult SCNT pigs produced by microinjection of Meishan pig fetus fibroblast cells into enucleated matured oocytes (maternal Landrace genetic background). Mitochondrial fractions were prepared from liver samples by mechanical homogenization and differential centrifugation. Liver mitochondria were then subjected to two-dimensional difference gel electrophoresis (2-D DIGE). Protein expression changes were confirmed with a volume ratio greater than 2 fold (P<0.05). 2-D DIGE analysis further revealed differential expression of three proteins between the Meishan (n=3) and Landrace (n=3) breeds. Differential expression patterns of 16 proteins were detected in SCNT pig liver tissue (n=3) when compared with Meishan control samples. However, none of the 16 proteins correlated with the three differentially expressed Meishan and Landrace liver mitochondrial proteins. In summary, alteration of mitochondrial protein expression levels was observed in adult SCNT pigs that did not reflect the breed difference of the recipient oocytes. Comparative proteomic analysis represents an important tool for further studies on SCNT animals. 相似文献
70.
Nakamura S Tsuchiya H Okahara N Nakagawa T Ohara N Yamamoto H Li TC Takeda N Ogasawara K Torii R 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2012,74(3):279-283
A serological survey of hepatitis E virus (HEV) antibody was conducted using 202 adult captive cynomolgus monkeys, who did not show any clinical signs of acute hepatitis. Out of these, 44 monkeys were sero-positive for anti-HEV IgG and all monkeys were negative for anti-HEV IgM. All positive monkeys came from either Vietnam or China, but none from the Philippines, Indonesia, or our facility. Selected 12 monkeys out of positive monkeys from Vietnam, including 9 positive and 3 negative, revealed mostly within the reference ranges for alanine aminotransferase (ALT) and asparatate aminotransferase (AST) by serum biochemistries. Their titers of anti-HEV IgG did not correlate with the concentrations of ALT and AST. Moreover, HEV-RNA could not be detected from any fecal specimens of the 12 monkeys. Thus, monkeys with anti-HEV IgG sero-positive did not seem to be source of the HEV-pollution, because 1) sero-positive monkeys did not excrete HEV-RNA from their feces, and 2) monkeys from the Philippines and Indonesia have remained to be sero-negative for anti-HEV IgG, even if the monkeys were kept in same animal room of our facility. From these results, it could be inferred that primary infection of HEV occurred in the exported countries, but not in our colony. The contamination of HEV in indoor-captive monkeys could be prevented by precise quarantine tests, including ELISA for detecting anti-HEV and RT-PCR for HEV RNA. 相似文献