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151.
Ghrelin was first identified and characterized from rat stomach as an endogenous ligand for the growth hormone secretagogue (GHS) receptor (GHS-R). Ghrelin also acts as an orexigenic factor and regulates energy balance in rodents. In goldfish, native ghrelin consists of 11 molecular variants, the major form being a 17-residue peptide with n-octanoic acid modification (n-octanoyl ghrelin17), and intraperitoneal (IP) administration of n-octanoyl ghrelin17 induces central actions such as stimulation of food intake and suppression of locomotor activity through capsaicin-sensitive afferents. Four types of GHS-Rs (1a-1, 1a-2, 2a-1 and 2a-2) have been identified in goldfish, and one GHS, GHRP-6, can activate only GHS-R2a-1 in vitro. However, there is no information about the effect of GHRP-6 on food intake and locomotor activity in goldfish in vivo. Therefore, in the present study, we examined whether IP-administered GHRP-6 would mimic the orexigenic action of n-octanoyl ghrelin17 and its suppression of locomotor activity. IP administration of GHRP-6 at 1pmol/g body weight (BW) stimulated food intake, and was equipotent to the orexigenic action of n-octanoyl ghrelin17 at 10 pmol/g BW. IP-injected GHRP-6 at 1 pmol/g BW also induced a significant decrease of locomotor activity, as was the case for IP-injected n-octanoyl ghrelin17 at 10 pmol/g BW. The action of GHRP-6 was blocked by IP-preinjected capsaicin at 160 nmol/g BW. These results suggest that the central action of GHRP-6 might be mediated via the GHS-R2a-1-signaling pathway, and subsequently through capsaicin-sensitive afferents in goldfish. 相似文献
152.
Osamu Sato Satoshi Miura Hiroyuki Maruyama Yanjuan Zhang Dayu Wu Wen Zhang Haitao Xu Ryotaro Matsuda Haoling Sun Jun Tao 《Inorganica chimica acta》2008,361(12-13):3659-3662
The magnetic and photo-magnetic properties of Co dinuclear compounds were studied. The Co compounds, [{Co(tpa)}2(dhbq)](BF4)3 · 2H2O and [{Co(tpa)}2(dhbq)](ClO4)3 · 2H2O, have the structure [(tpa)CoIII-LS–(μ-dhbq)3?–CoIII-LS(tpa)]3? (where LS, H2dhbq, tpa denote low-spin, 2,5-di-hydroxy-1,4-benzoquinone and tris(2-pyridylmethyl)amine, respectively) at room temperature. On heating, these compounds exhibit valence-tautomeric inter-conversion; [(tpa)CoIII-LS–(μ-dhbq)3?–CoIII-LS(tpa)]3? ? [(tpa)CoII-HS–(μ-dhbq)2?–CoIII-LS(tpa)]3? (where HS denotes high-spin). Furthermore, both of these compounds exhibit photo-induced valence tautomerism at low temperature (<60 K). These results show that the electronic structures of these complexes can be controlled by modifying the counter anions. 相似文献
153.
Tashiro Y Kaneko W Sun Y Shibata K Inokuma K Zendo T Sonomoto K 《Applied microbiology and biotechnology》2011,89(6):1741-1750
We isolated and characterized a d-lactic acid-producing lactic acid bacterium (d-LAB), identified as Lactobacillus delbrueckii subsp. lactis QU 41. When compared to Lactobacillus coryniformis subsp. torquens JCM 1166 T and L. delbrueckii subsp. lactis JCM 1248 T, which are also known as d-LAB, the QU 41 strain exhibited a high thermotolerance and produced d-lactic acid at temperatures of 50 °C and higher. In order to optimize the culture conditions of the QU 41 strain, we examined
the effects of pH control, temperature, neutralizing reagent, and initial glucose concentration on d-lactic acid production in batch cultures. It was found that the optimal production of 20.1 g/l d-lactic acid was acquired with high optical purity (>99.9% of d-lactic acid) in a pH 6.0-controlled batch culture, by adding ammonium hydroxide as a neutralizing reagent, at 43 °C in MRS
medium containing 20 g/l glucose. As a result of product inhibition and low cell density, continuous cultures were investigated
using a microfiltration membrane module to recycle flow-through cells in order to improve d-lactic acid productivity. At a dilution rate of 0.87 h−1, the high cell density continuous culture exhibited the highest d-lactic acid productivity of 18.0 g/l/h with a high yield (ca. 1.0 g/g consumed glucose) and a low residual glucose (<0.1 g/l)
in comparison with systems published to date. 相似文献
154.
Zhang X Li C Gao H Nabeka H Shimokawa T Wakisaka H Matsuda S Kobayashi N 《Cellular & molecular biology letters》2011,16(2):279-295
We investigated the effects of Rho-associated kinase (ROCK) on migration and cytoskeletal organization in primary human osteoblasts
and Saos-2 human osteosarcoma cells. Both cell types were exposed to two different ROCK inhibitors, Y-27632 and HA-1077. In
the improved motility assay used in the present study, Y-27632 and HA-1077 significantly increased the migration of both osteoblasts
and osteosarcoma cells on plastic in a dose-dependent and reversible manner. Fluorescent images showed that cells of both
types cultured with Y-27632 or HA-1077 exhibited a stellate appearance, with poor assembly of stress fibers and focal contacts.
Western blotting showed that ROCK inhibitors reduced myosin light chain (MLC) phosphorylation within 5 min without affecting
overall myosin light-chain protein levels. Inhibition of ROCK activity is thought to enhance the migration of human osteoblasts
through reorganization of the actin cytoskeleton and regulation of myosin activity. ROCK inhibitors may be potentially useful
as anabolic agents to enhance the biocompatibility of bone and joint prostheses. 相似文献
155.
Microarray technology has become employed widely for biological researchers to identify genes associated with conditions such as diseases and drugs. To date, many methods have been developed to analyze data covering a large number of genes, but they focus only on statistical significance and cannot decipher the data with biological concepts. Gene Ontology (GO) is utilized to understand the data with biological interpretation; however, it is restricted to specific ontology such as biological process, molecular function, and cellular component. Here, we attempted to apply MeSH (Medical Subject Headings) to interpret groups of genes from biological viewpoint. To assign MeSH terms to genes, in this study, contexts associated with genes are retrieved from full set of MEDLINE data using machine learning, and then extracted MeSH terms from retrieved articles. Utilizing the developed method, we implemented a software called BioCompass. It generates high-scoring lists and hierarchical lists for diseases MeSH terms associated with groups of genes to utilize MeSH and GO tree, and illustrated a wiring diagram by linking genes with extracted association from articles. Researchers can easily retrieve genes and keywords of interest, such as diseases and drugs, associated with groups of genes. Using retrieved MeSH terms and OMIM in conjunction with, we could obtain more disease information associated with target gene. BioCompass helps researchers to interpret groups of genes such as microarray data from a biological viewpoint. 相似文献
156.
Isolation and characterization of the human ornithine transcarbamylase gene: structure of the 5'-end region 总被引:6,自引:0,他引:6
A Hata T Tsuzuki K Shimada M Takiguchi M Mori I Matsuda 《Journal of biochemistry》1986,100(3):717-725
We isolated over 20 phage clones carrying the ornithine transcarbamylase (OTC) [EC 2.1.3.3] gene, from two independently constructed human genomic DNA libraries, using as probes either a rat OTC cDNA or several nuclear DNA fragments derived from some of these isolated clones. These clones, classified into 10 different groups, overlapped and spanned a region of more than 85 kilobase pairs of the human genomic DNA. Restriction mapping and Southern blot analyses demonstrated that one of the clones covers the 5'-end region of the OTC gene. We sequenced the 5'-end region of the OTC gene and found that it covered 665 base pairs of the 5'-flanking region, the complete first exon and a part of the first intron (150 base pairs). In the 5'-flanking region, there were two pairs of putative CAAT and TATA boxes and one enhancer core-like sequence, GTGGAAAG. The first exon contained a coding region for most of the OTC presequence, i.e. 26 out of 32 amino acid residues of the presequence, including the initiation methionine. 相似文献
157.
Youichi Kawakita Kazuhiro Miwa Masaki Seto Hiroshi Banno Yoshikazu Ohta Toshiya Tamura Tadashi Yusa Hiroshi Miki Hidenori Kamiguchi Yukihiro Ikeda Toshimasa Tanaka Keiji Kamiyama Tomoyasu Ishikawa 《Bioorganic & medicinal chemistry》2012,20(20):6171-6180
During the course of our studies on a novel HER2/EGFR dual inhibitor (TAK-285), we found an alternative potent pyrrolo[3,2-d]pyrimidine compound (1a). To enhance the pharmacokinetic (PK) profile of this compound, we conducted chemical modifications into its N-5 side chain and conversion of the chemically modified compounds into their salts. Among them, 2cb, the tosylate salt of compound 2c, showed potent HER2/EGFR kinase inhibitory activity (IC50: 11/11 nM) and cellular growth inhibitory activity (BT-474 cell GI50: 56 nM) with a good drug metabolism and PK (DMPK) profile. Furthermore, 2cb exhibited significant in vivo antitumor efficacy in both mouse and rat xenograft models with transplanted 4-1ST gastric cancer cell lines (mouse, T/C = 0%, 2cb po bid at 100 mg/kg; rat, T/C: -1%, 2cb po bid at 25 mg/kg). 相似文献
158.
Tomoyuki Hayashi Hisashi Doyama Yukihiro Shirota Hirokazu Tsuji Youhei Marukawa Hajime Ohta Kazuhiro Miwa Takaharu Masunaga Shuichi Terasaki Yutaka Matano Kunihiro Tsuji Yoshibumi Kaneko Toshihide Okada Hiroshi Kurumaya Shuichi Kaneko 《PloS one》2014,9(7)
Objectives
Magnifying narrow-band imaging (M-NBI) is more accurate than white-light imaging for diagnosing small gastric cancers. However, it is uncertain whether moving M-NBI images have additional effects in the diagnosis of gastric cancers compared with still images.Design
A prospective multicenter cohort study.Methods
To identify the additional benefits of moving M-NBI images by comparing the diagnostic accuracy of still images only with that of both still and moving images. Still and moving M-NBI images of 40 gastric lesions were obtained by an expert endoscopist prior to this prospective multicenter cohort study. Thirty-four endoscopists from ten different Japanese institutions participated in the prospective multicenter cohort study. Each study participant was first tested using only still M-NBI images (still image test), then tested 1 month later using both still and moving M-NBI images (moving image test). The main outcome was a difference in the diagnostic accuracy of cancerous versus noncancerous lesions between the still image test and the moving image test.Results
Thirty-four endoscopists were analysed. There were no significant difference of cancerous versus noncancerous lesions between still and moving image tests in the diagnostic accuracy (59.9% versus 61.5%), sensitivity (53.4% versus 55.9%), and specificity (67.0% versus 67.6%). And there were no significant difference in the diagnostic accuracy between still and moving image tests of demarcation line (65.4% versus 65.5%), microvascular pattern (56.7% versus 56.9%), and microsurface pattern (48.1% versus 50.9%). Diagnostic accuracy showed no significant difference between the still and moving image tests in the subgroups of endoscopic findings of the lesions.Conclusions
The addition of moving M-NBI images to still M-NBI images does not improve the diagnostic accuracy for gastric lesions. It is reasonable to concentrate on taking sharp still M-NBI images during endoscopic observation and use them for diagnosis.Trial registration
Umin.ac.jp UMIN-CTR000008048 相似文献159.
Haneda K Tagashira M Yoshino E Takeuchi M Inazu T Toma K Iijima H Isogai Y Hori M Takamatsu S Fujibayashi Y Kobayashi K Takeuchi M Yamamoto K 《Glycoconjugate journal》2004,21(6):377-386
Starting from N-glycosylated eel calcitonin derivatives that contain an N-acetyl-D-glucosamine residue specifically at the 3rd, 14th, 20th or 26th amino acid residue, corresponding glycopeptides with a complex-type oligosaccharide attached to the respective amino acid residue were synthesized by means of a transglycosylation reaction catalyzed by an endo-beta-N-acetylglucosaminidase from Mucor hiemalis . The use of a recombinant enzyme and an excess of a glycosyl donor led to a yield in excess of 60%. Calcitonin derivatives containing truncated oligosaccharides were also prepared via digestion of the complex-type N-glycan with exoglycosidases. Using these N-glycosylated calcitonin derivatives, the effect of carbohydrate structure and glycosylation site on the three-dimensional structure and the biological activity of the peptide were studied. The conformation of the peptide backbone did not change irrespective of the carbohydrate structure or the glycosylation site. However, hypocalcemic activity, calcitonin-receptor binding activity and the biodistribution of the derivatives were affected by the glycosylation and were dependent on both the carbohydrate structure and the glycosylation site. Although the larger oligosaccharides tended to hinder receptor binding, the biodistribution altered by N-glycosylation appeared to enhance the hypocalcemic activity in some cases, and the magnitude of the effect was dependent on the site of glycosylation. 相似文献
160.
Akihiro Tazumi Yuki Kakinuma Naoaki Misawa John E Moore Beverley C Millar Motoo Matsuda 《BMC microbiology》2009,9(1):256