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排序方式: 共有145条查询结果,搜索用时 250 毫秒
1.
Takahiro Ishii Tatsufumi Okino Yosuke Mino Hiroaki Tamiya Fuyuhiko Matsuda 《Plant Growth Regulation》2007,52(2):131-139
Starfish waste has been shown to be an effective compost material not only in the promotion of plant growth but also in terms
of having insecticidal activity. In the present study, plant growth regulation by chemicals from starfish was examined. The
aqueous fraction from a hot water extract of the starfish Asterias amurensis Lütken showed plant-growth activity, while the aqueous fraction from a methanol extract inhibited growth of Brassica campestris. The lipophilic fraction from the methanol extract also exhibited a plant growth-promoting effect. The active components
from each extract were identified. Asterubine from the hot water extract promoted plant growth. A ceramide from the lipophilic
fraction showed root growth promoting effect, and three glucocerebrosides had promotive effects on the entire plant. Asterosaponins
were identified as the main growth inhibitors in the aqueous fraction of the methanol extract. These active compounds from
starfish waste could be analyzed as potential plant growth regulators in agricultural applications in the future. 相似文献
2.
A survey of oligotrophic Lake Rara, the biggest lake in Nepal, was carried out from 1982 till 1984. Mean depth is 100 m, and
maximum depth is 167 m. The surface area covers 9.8 km2, and the lake contains 0.98 km3 volume of water.
Transparency was about 16 m, photoquantum yield decreased exponentially with depth below 5 m, and the extinction coefficient
was 8.3 × 10−2. The concentration of Chl.-a was in the range of 0.06–0.46 mg m−3, and total nitrogen was 18–30 μg 1−1. The whole water column was well oxygenated. Primary productivity was extremely low. It has more than 30 inflowing brooks
and one outlet. The water quality of the brooks changes drastically with their location. The pH, electrical conductivity,
and EDTA hardness in the waters from a landslide area were high. In the waters from a rich pine forest they were extremely
low.
The zooplankton consisted of two species of protozoa, five species of rotifers, two species of Cladocera, and two species
of Copepoda. The zooplankton density range was 6200–16200 individuals m−3. The minimum was on November 11th, 1983 and the maximum on August 19th, 1983. 相似文献
3.
Multiple gene-like sequences related to the rabbit hepatic progesterone 21-hydroxylase cytochrome P-450 1 总被引:10,自引:0,他引:10
R H Tukey S Okino H Barnes K J Griffin E F Johnson 《The Journal of biological chemistry》1985,260(24):13347-13354
Rabbits exhibit phenotypic differences, 21H and 21L, in the rate of hepatic progesterone 21-hydroxylation that reflect 10-fold higher microsomal concentrations of cytochrome P-450 1 in 21H rabbits. A cDNA library in pBR322 was prepared from liver mRNA isolated from a 21H rabbit. A clone, p1-8, producing a hybrid protein resulting from the insertion of the cDNA into the beta-lactamase gene of the plasmid expressed 5 distinct epitopes that were recognized by a panel of monoclonal antibodies developed toward P-450 1. RNAs selected from total hepatic mRNA by filter hybridization with p1-8 yield at least two electrophoretically distinct proteins when translated in vitro and immunoprecipitated with the 3C3 monoclonal antibody. Only one of the two proteins is recognized by the 1F11 monoclonal antibody, which is highly specific for P-450 1, and the immunoprecipitated protein exhibits the electrophoretic mobility of P-450 1. The other protein remains unidentified. Northern blot analysis indicates that the 3' noncoding portion of p1-8 hybridizes to higher steady state concentrations of polyadenylated RNA in the 21H as compared to 21L rabbits. This correspondence in expression with that of P-450 1 in the 21H and 21L phenotypes further suggests that p1-8 encodes P-450 1 or a closely related protein. The cDNA is 1871 base pairs in length and encodes a protein of 487 amino acids. Southern blot analysis indicates that several independent, gene-like sequences hybridize with the 3' noncoding region of p1-8 under conditions of high stringency. These results indicate that P-450 1 is a member of an extensive multigene family. 相似文献
4.
Norimichi Kan Takashi Okino Masaki Nakanishi Kohei Satoh Kazuhisa Ohgaki Takayoshi Tobe 《Cancer immunology, immunotherapy : CII》1989,28(4):260-266
Summary The synergistic antitumor effect of interleukin-2(IL-2)-cultured tumor-bearer spleen cells (cultured lymphocytes) and immune fresh spleen cells was examined. Tumor-bearer cultured lymphocytes were obtained by culturing BALB/c spleen cells from syngeneic MOPC104E-tumor-bearing mice for 11 days with crude IL-2 and a soluble tumor extract. These cultured lymphocytes had weak antitumor activity when transferred i.p. into tumor-bearing mice that had been inoculated i.p. with 105 tumor cells 5 days previously. Immune fresh spleen cells, obtained from mice in complete remission after the treatment with cyclophosphamide, also had weak antitumor activity when transferred at the same schedule. The cultured cells and the fresh cells, mixed together before transfer, significantly augmented the therapeutic effect. At least 1×107 tumor-bearer cultured lymphocytes and 4×107 immune cells were needed for the synergistic effect. A tumor-specific combination was needed for both cultured and fresh cells. The effective subpopulation of tumor-bearer cultured lymphocytes was a cytotoxic one from an Lyt2+ precursor, and that of the immune fresh spleen cells was noncytotoxic, Lytl+ and Lyt2+ T-cells.A similar synergistic effect was also observed during in vitro coculture of tumor-bearer and immune cells. Cytotoxicity, as assessed by the 51Cr-release test, of tumor-bearer IL-2-cultured lymphocytes was maintained most effectively after 3 or 4 days of culture without IL-2 when the lymphocytes were cocultured with immune fresh spleen cells and tumor cells. 相似文献
5.
Shukuro Araki Shigehiro Yi Tatsufumi Murakami Susumu Watanabe Shinichi Ikegawa Kiyoshi Takahashi Ken-ichi Yamarnura 《Molecular neurobiology》1994,8(1):15-23
To analyze the pathologic processes of amyloid deposition in type I familial amyloidotic polyneuropathy (FAP), mice were made
transgenic by introducing the human mutant transthyretin (TTR) gene(MT-hMet 30). An inbred strain of mouse, C57 BL/6, was
chosen. Transgenic mice were killed using ether anesthesia at 3-mo intervals up to 24 mo after birth. In these transgenic
mice, amyloid deposition started in the gastrointestinal tract, cardiovascular system, and kidneys and extended to various
other organs and tissues with advancing age. The pattern of amyloid deposition was similar to that observed in human autopsy
cases of FAP, except for its absence in the choroid plexus and in the peripheral and autonomic nervous systems.
We extracted the amyloid fibrils from kidneys of these mice with a human mutant TTR gene and analyzed them immunochemically
and electronmicroscopically. Deposited amyloid was shown to be composed of human mutant TTR and mouse serum amyloid P component.
Amyloid fibril from transgenic mice was morphologically and immunohistochemically similar to that of human FAP.
The most striking pathologic feature of the transgenic mice was the absence of amyloid deposition in the peripheral and autonomic
nervous tissues. Thus, other intrinsic factors may be involved in amyloid deposition in the nervous tissues of human FAP. 相似文献
6.
Nitric Oxide Reversibly Suppresses Xanthine Oxidase Activity 总被引:10,自引:0,他引:10
Masami Fukahori Kohji Ichimori Hideyuki Ishida Hiroe Nakagawa Haruka Okino 《Free radical research》1994,21(4):203-212
The effects of nitric oxide (NO) on xanthine oxidase (XOD) activity and the site(s) of the redox center(s) affected were investigated. XOD activity was determined by superoxide (O2-) generation and uric acid formation. NO reversibly and dose-dependently suppressed XOD activity in both determination methods. The suppression interval also disclosed a dose-dependent prolongation. The suppression occurred irrespective of the presence or absence of xanthine; indicating that the reaction product of NO and O2-, peroxynitrite, is not responsible for the suppression. Application of synthesized peroxynitrite did not affect XOD activity up to 2 μM. Methylene blue, which is an electron acceptor from Fe/S center, prevented the NO-induced inactivation. The results indicate that NO suppresses XOD activity through reversible alteration of the flavin prosthetic site. 相似文献
7.
Xu X Monjusho H Inagaki M Hama Y Yamaguchi K Sakaguchi K Iwamori M Okino N Ito M 《Journal of biochemistry》2007,141(1):1-7
The use of bovine brain has been prohibited in many countries because of the world-wide prevalence of mad cow disease, and thus porcine brain is expected to be a new source for the preparation of gangliosides. Here, we report the presence of a ganglioside in porcine brain which is strongly resistant to hydrolysis by endoglycoceramidase, an enzyme capable of cleaving the glycosidic linkage between oligosaccharides and ceramides of various glycosphingolipids. Five major gangliosides (designated PBG-1, 2, 3, 4, 5) were extracted from porcine brain by Folch's partition, followed by mild alkaline hydrolysis and PBA column chromatography. We found that PBG-2, but not the others, was strongly resistant to hydrolysis by the enzyme. After the purification of PBG-2 with Q-Sepharose, Silica gel 60 and Prosep-PB chromatographies, the structure of PBG-2 was determined by GC, GC-MS, FAB-MS and NMR spectroscopy as Fucalpha1-2Galbeta1-3GalNAcbeta1-4(NeuAcalpha2-3)Galbeta1-4Glcbeta1-1'Cer (fucosyl-GM1a). The ceramide was mainly composed of C18:0 and C20:0 fatty acids and d18:1 and d20:1 sphingoid bases. The apparent kcat/Km for fucosyl-GM1a was found to be 30 times lower than that for GM1a, indicating that terminal fucosylation makes GM1a resistant to hydrolysis by the enzyme. This report indicates the usefulness of endoglycoceramidase to prepare fucosyl-GM1a from porcine brain. 相似文献
8.
9.
Hayashi Y Okino N Kakuta Y Shikanai T Tani M Narimatsu H Ito M 《The Journal of biological chemistry》2007,282(42):30889-30900
Using C6-NBD-glucosylceramide (GlcCer) as a substrate, we detected the activity of a conduritol B epoxide-insensitive neutral glycosylceramidase in cytosolic fractions of zebrafish embryos, mouse and rat brains, and human fibroblasts. The candidates for the enzyme were assigned to the Klotho (KL), whose family members share a beta-glucosidase-like domain but whose natural substrates are unknown. Among this family, only the KL-related protein (KLrP) is capable of degrading C6-NBD-GlcCer when expressed in CHOP cells, in which Myc-tagged KLrP was exclusively distributed in the cytosol. In addition, knockdown of the endogenous KLrP by small interfering RNA increased the cellular level of GlcCer. The purified recombinant KLrP hydrolyzed 4-methylumbelliferyl-glucose, C6-NBD-GlcCer, and authentic GlcCer at pH 6.0. The enzyme also hydrolyzed the corresponding galactosyl derivatives, but each k(cat)/Km was much lower than that for glucosyl derivatives. The x-ray structure of KLrP at 1.6A resolution revealed that KLrP is a (beta/alpha)8 TIM barrel, in which Glu(165) and Glu(373) at the carboxyl termini of beta-strands 4 and 7 could function as an acid/base catalyst and nucleophile, respectively. The substrate-binding cleft of the enzyme was occupied with palmitic acid and oleic acid when the recombinant protein was crystallized in a complex with glucose. GlcCer was found to fit well the cleft of the crystal structure of KLrP. Collectively, KLrP was identified as a cytosolic neutral glycosylceramidase that could be involved in a novel nonlysosomal catabolic pathway of GlcCer. 相似文献
10.
We examined the relationship between body size of the riparian spider Nephila clavata and the contribution of allochthonous (aquatic insects) and autochthonous (terrestrial insects) sources to its diet using
stable isotope analysis. During the study period from July to September, the body size of the females increased remarkably
(about 60-fold) but that of males remained small. The biomass of both aquatic and terrestrial insects trapped on the spider
webs increased with spider size, with the biomass of the former ranging between 30 and 70% of that of the terrestrial insects.
The average relative contribution of aquatic insects to the diet of the spiders, calculated from δ13C values, was 40–50% in spiders in the early juvenile and juvenile stages, 35% in adult males and 4% in adult females. There
was a significant negative relationship between the relative contribution of aquatic insects and body size of the female spiders.
We conclude that aquatic insects might be an important seasonal dietary subsidy for small spiders and that these allochthonous
subsidies may facilitate the growth of riparian spiders, which may in turn enable the spiders to feed on larger prey. 相似文献