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991.
Robert G Boyle John Humphries Tim Mitchell Graham A Showell Robert Apaya Hiroaki Iijima Hiroshi Shimada Tomonori Arai Hiroaki Ueno Yoshihiro Usui Toshiro Sakaki Etsuko Wada Keiji Wada 《Journal of peptide science》2005,11(3):136-141
Extensive SAR studies on the unselective BRS3 agonist, [H-D-Phe6,beta-Ala11,Phe13,Nle14]-bombesin-(6-14)-nonapeptide amide, have highlighted structural features important for BRS3 activity and have provided guidance as to the design of selective agonists. A radically modified heptapeptide agonist, maintaining only the Trp-Ala moiety of the parent [H-D-Phe6,betaAla11,Phe13,Nle14]-peptide amide, and with a very different carboxyl terminal region, has been produced which was potent at BRS3 and essentially had no NMB or GRP receptor activity. Its structure is Ac-Phe-Trp-Ala-His(tauBzl)-Nip-Gly-Arg-NH2. 相似文献
992.
Molecular cloning of cDNA of S100 alpha subunit mRNA 总被引:1,自引:0,他引:1
R Kuwano T Maeda H Usui K Araki T Yamakuni Y Ohshima T Kurihara Y Takahashi 《FEBS letters》1986,202(1):97-101
The primary structure of the bovine S-100 alpha mRNA on the basis of molecular cloning and sequence analysis of the cDNA are described. The sequence is composed of 532 bp which include the 282 bp of the complete coding region, 89 bp at the 5'-noncoding region, 161 bp at the 3'-noncoding region, polyadenylation signal, ATTAAA and poly(A) tail. Northern blot analysis shows that the size of S-100 alpha mRNA is about 700-800 bases long and a single mRNA occurs in bovine brain. Bovine brain contains both S100 alpha and beta subunits and their mRNAs. In contrast, the rat brain contains only S100 beta subunit and its mRNA. 相似文献
993.
Oligosaccharides involved in glycoconjugates play important roles in a number of biological events. To elucidate the biological functions of oligosaccharides, sufficient quantities of structurally defined oligosaccharides, are of limited availability by traditional purification methods, are required. Hence, chemical and enzymatic syntheses of oligosaccharides are becoming increasingly important in glycobiology and glycotechnology. In addition, oligosaccharides often occur as glycoconjugates attached to proteins or lipids. Hence, the development of simple and effective methods for synthesizing neoglycoconjugates such as neoglycoprotein and neoglycolipids is essential for an understanding of the biological function of these molecules. Here we review the most recent developments in the enzymatic synthesis of oligosaccharides and neoglycoconjugates. 相似文献
994.
Passive protective activities of three different classes of monoclonal antibodies in mice against challenge with strain ATCC 31432 (capsular type I) of Staphylococcus epidermidis were examined. Monoclonal IgM antibody passively protected mice against challenge with the homologous strain, whereas monoclonal IgG1 and IgG2b antibodies did not. The protective activity of IgM was absorbed by the cell surface antigen extracted from the homologous strain but not by the antigen from heterologous strains. Rapid reduction of viable cells took place in the peritoneal cavity of mice immunized with monoclonal IgM as early as 6 h after the challenge with the homologous strain. An enzyme-linked immunosorbent inhibition assay showed there was remarkable inhibition with the homologous cell surface antigen but not with heterologous preparations from other strains. Results suggest that in the mouse the major passive protection against the S. epidermidis strain is provided by the IgM antibody to the cell surface antigen. 相似文献
995.
Keisuke Suzuki Masayuki Miyamoto Tomoyuki Miyamoto Yuichi Inoue Kentaro Matsui Shingo Nishida Kenichi Hayashida Akira Usui Yoichiro Ueki Masaki Nakamura Momoyo Murata Ayaka Numao Yuji Watanabe Shiho Suzuki Koichi Hirata 《PloS one》2015,10(9)
Background
Because the prevalence and characteristics of primary headache have yet to be thoroughly studied in patients with hypersomnia disorders, including narcolepsy and idiopathic hypersomnia, we examined these parameters in the Japanese population.Methods
In a multicentre cross-sectional survey, among 576 consecutive outpatients with sleep disorders, 68 narcolepsy patients and 35 idiopathic hypersomnia patients were included. Additionally, 61 healthy control subjects participated. Semi-structured headache questionnaires were administered to all participants.Results
The patients with narcolepsy (52.9%) and idiopathic hypersomnia (77.1%) more frequently experienced headache than the healthy controls (24.6%; p<0.0001). The prevalence rates were 23.5%, 41.2% and 4.9% for migraine (p<0.0001) and 16.2%, 23.5% and 14.8% (p = 0.58) for tension-type headache among the narcolepsy patients, the idiopathic hypersomnia patients and the control subjects, respectively. Those who experienced migraine more frequently experienced excessive daytime sleepiness, defined as an Epworth Sleepiness Scale score of ≥10, than those who did not experience headache among the patients with narcolepsy (93.8% vs. 65.6%, p = 0.040) and idiopathic hypersomnia (86.7% vs. 37.5%, p = 0.026). Dream-enacting behaviour (DEB), as evaluated by the rapid eye movement sleep disorders questionnaire, was more frequently observed in the narcolepsy patients than in the idiopathic hypersomnia patients and the control subjects. An increased DEB frequency was observed in the narcolepsy patients with migraines compared to those without headache.Conclusions
Migraines were frequently observed in patients with narcolepsy and idiopathic hypersomnia. DEB is a characteristic of narcolepsy patients. Further studies are required to assess the factors that contribute to migraines in narcolepsy and idiopathic hypersomnia patients. 相似文献996.
Kawai Y Kimura Y Lezhava A Kanamori H Usui K Hanami T Soma T Morlighem JÉ Saga S Ishizu Y Aoki S Endo R Oguchi-Katayama A Kogo Y Mitani Y Ishidao T Kawakami C Kurata H Furuya Y Saito T Okazaki N Chikahira M Hayashi E Tsuruoka S Toguchi T Saito Y Ban T Izumi S Uryu H Kudo K Sakai-Tagawa Y Kawaoka Y Hirai A Hayashizaki Y Ishikawa T 《PloS one》2012,7(1):e30236
997.
ATF3 stimulated promoter activity of EphA1 by 3.4-fold in ATF3-dependent angiogenesis in vitro. Although tyrosine kinase activation of EphA1 was dispensable, binding of EphA1 to fibronectin through its type I repeat played an essential role in the angiogenesis. Recombinant proteins containing fibronectin 10th to 12th type I repeat (I 10-12) but not I 12 could inhibit the angiogenesis in vitro by competitively targeting EphA1 with the full-length fibronectin. However, I 12 acquired a higher affinity toward EphA2 with K(d) 18 nm and inhibited vascular endothelial growth factor-dependent angiogenic invasion in a Matrigel plug assay. 相似文献
998.
Jose?C?NacherEmail author Nobuhisa?Ueda Takuji?Yamada Minoru?Kanehisa Tatsuya?Akutsu 《BMC bioinformatics》2004,5(1):207
Background
Many real networks can be understood as two complementary networks with two kind of nodes. This is the case of metabolic networks where the first network has chemical compounds as nodes and the second one has nodes as reactions. In general, the second network may be related to the first one by a technique called line graph transformation (i.e., edges in an initial network are transformed into nodes). Recently, the main topological properties of the metabolic networks have been properly described by means of a hierarchical model. While the chemical compound network has been classified as hierarchical network, a detailed study of the chemical reaction network had not been carried out. 相似文献999.
Luziga C Usui M Yoichiro H Kazwala R Yamamoto Y Mamba K 《Journal of molecular histology》2007,38(1):65-77
Megalin/the low density lipoprotein receptor-related protein-2 (LRP-2) is expressed in a variety of epithelia and mediates
endocytosis of numerous substances. Megalin is also shown to bind clusterin with high affinity. In the pituitary gland, clusterin
is localized in endocrine cells, folliculostellate (FS) cells and colloids. The present study examines the expression pattern
of megalin within the gland and assesses its cellular localization to that of clusterin so as to deduce their functional implications
in colloidal accumulation as relevant in vivo. Quantity of megalin mRNA expression in pituitary and other endocrine tissues
was quantified by real-time PCR using SYBR-green I detective system. High levels were detected in kidneys and pituitary. In
situ hybridization showed megalin mRNA in FS cells. Megalin protein detected by immunohistochemistry was also observed in
FS cells. Immunoelectron microscopy clearly showed the localization of megalin in peripheral region of colloid-containing
follicles and on vesicular structures in FS cells. Immunolabeling was also found to be associated with membranes of vacuoles
in apoptotic endocrine cells and cell remnants engulfed by FS cells. Double immunofluorescence labeling was performed to determine
whether megalin and clusterin in the anterior pituitary were present within the same cell. Simultaneous localization was detected
in almost all FS cells surrounding colloids and in several foci of FS cells surrounding endocrine cells. These findings suggest
that megalin may drive ingestion of clusterin complexes with products of digested apoptotic endocrine cells in FS cells, and
thereby providing a potential mechanism for a receptor mediated uptake of degenerating endocrine cells and secretion of colloid. 相似文献
1000.
Fujieda H Usui S Suzuki T Nakagawa H Ogura M Makishima M Miyata N 《Bioorganic & medicinal chemistry letters》2007,17(15):4351-4357
To find novel PPARdelta-selective agonists, we designed and synthesized phenylpropanoic acid derivatives bearing 6-substituted benzothiazoles. Optimization of this series led to the identification of a potent and selective PPARdelta agonist 17. Molecular modeling suggested that compound 17 occupies the Y-shaped pocket of PPARdelta appropriately. 相似文献