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121.
A new lectin gene was cloned from Amorphophallus konjac. The full-length cDNA of Amorphophallus konjac agglutinin (aka) was 736 bp and contained a 474 bp open reading frame encoding a 158 amino acid protein. Homology analysis revealed that the lectin from this Araceae species belonged to the superfamily of monocot mannose-binding proteins. Molecular modeling of AKA indicated that the three-dimensional structure of AKA strongly resembles that of the snowdrop lectin. Southern blot analysis of the genomic DNA revealed that aka belonged to a low-copy gene family. Northern blot analysis demonstrated that aka expression was tissue-specific with the strongest expression being found in root. 相似文献
122.
Chai W Sakamaki H Kitanaka S Saito M Horiuchi CA 《Bioscience, biotechnology, and biochemistry》2003,67(1):218-220
The biological degradation of 2,2-bis(4-hydroxyphenol)propane (1; bisphenol A, BPA), a representative endocrine disruptor, was studied with plant-cultured cells of Caragana chamlagu. An initial BPA concentration of 425 microM in an aqueous solution was degraded by C. chamlagu at 25 degrees C for 2 days in the dark, and two intermediates were then completely dissipated after 10 days. 相似文献
123.
Chai W Breitenbucher JG Kwok A Li X Wong V Carruthers NI Lovenberg TW Mazur C Wilson SJ Axe FU Jones TK 《Bioorganic & medicinal chemistry letters》2003,13(10):1767-1770
Continued exploration of the SAR around the lead imidazopyridine histamine H(3) antagonist 1 has led to the discovery of several related series of heterocyclic histamine H(3) antagonists. The synthesis and SAR of indolizine, indole and pyrazolopyridine based compounds are now described. 相似文献
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Cho GW Kim MH Chai YG Gilmor ML Levey AI Hersh LB 《The Journal of biological chemistry》2000,275(26):19942-19948
Metabolic labeling of a mutant PC12 cell line, A123.7, expressing recombinant rat vesicular acetylcholine transporter (VAChT) with radiolabeled inorganic phosphate was used to demonstrate phosphorylation of the transporter on a serine residue. Mutational analysis was used to demonstrate that serine 480, which is located on the COOH-terminal cytoplasmic tail, is the sole phosphorylation site. Phosphorylation of serine 480 was attributable to the action of protein kinase C. Using a permanently dephosphorylated form of rat VAChT, S480A rVAChT, it was shown that this mutant displays the same kinetics for the transport of acetylcholine and the binding of the inhibitor vesamicol as does the wild type transporter. However, sucrose gradient density centrifugation showed that, unlike wild type VAChT, the S480A mutant did not localize to synaptic vesicles. These results suggest that phosphorylation of serine 480 of VAChT is involved in the trafficking of this transporter. 相似文献
126.
Chai YC Binion DG Chisolm GM 《American journal of physiology. Heart and circulatory physiology》2000,279(4):H1830-H1838
We previously reported that oxidized low-density lipoprotein and one of its constituents, lysophosphatidylcholine (lysoPC), caused smooth muscle cell proliferation that was inhibitable by vitamin E and by a neutralizing antibody against basic fibroblast growth factor-2 (FGF-2). We now show that the mitogenic activity of lysolipids is highly dependent on structure. Phospholipids with palmitoyl fatty acid and phosphocholine induced DNA synthesis optimally. Shorter and longer fatty acids were significantly less potent, as were phosphoserine and phosphoethanolamine head groups. Structurally related phospholipids [platelet-activating factor (PAF) and lysoPAF] were also mitogens and acted via an analogous FGF-2-dependent, vitamin E-inhibitable mechanism. The mechanism of lysoPC stimulation was distinct from that of another phospholipid mitogen, lysophosphatidic acid (lysoPA), in that lysoPC stimulation was not pertussis toxin inhibitable. Furthermore, lysoPA stimulation was not inhibitable by vitamin E. Despite its distinct cellular pathway for stimulation, lysoPA also ultimately led to FGF-2 release. Our data show that specific structural attributes of lysoPC, PAF, and lysoPAF enable these agents to mediate smooth muscle cell release of FGF-2, which in turn stimulates proliferation. 相似文献
127.
A small-scale epidemiological survey was undertaken during 1997-1998 on the residents along the Osib-chon (Stream), Samchok-shi (City), Kangwon-do (Province), to evaluate the status of Metagonimus yokogawai infection. A total of 165 fecal samples was collected and examined by cellophane thick smear and formalin-ether sedimentation techniques. The egg positive rate of M. yokogawai was 29.7%, showing a remarkable difference between males (46.6%) and females (16.3%). To obtain the adult flukes of M. yokogawai, 11 egg positive persons were treated with praziquantel and purged with magnesium sulfate. A total of 242,119 adult flukes (average 22,010 per person, 367-119,650 in range) was collected from diarrheic stools, all of which were identified as M. yokogawai. The results show that M. yokogawai is still highly endemic in this area. 相似文献
128.
1988年Olins[1]发现T7噬菌体基因10的先导序列(T7g10L)具有明显的促进基因翻译的作用.本文构建了含T7g10L的表达载体pSC34,并尝试表达了几个不同类型的基因.1材料与方法1.1菌株大肠杆菌菌株TAP106为本室储存.TAP10... 相似文献
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Similar or Totally Different: the Adjustment of the Twist Conformation Through Minor Structural Modification,and Dramatically Improved Performance for Dye‐Sensitized Solar Cell
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Zhaofei Chai Mei Wu Manman Fang Sushu Wan Ting Xu Runli Tang Yujun Xie Anyi Mei Hongwei Han Qianqian Li Zhen Li 《Liver Transplantation》2015,5(18)
A novel approach for enhancing the performance of dye‐sensitized solar cells is presented. It is based on the analysis of five sensitizers by utilizing triarylamine as donor, thiophene benzothiadiazole as chromophore and substituted thienyl linked with cyanoacrylic acid as the anchoring group (LI‐80‐LI‐84). Accompanied with the increasing steric hindrance of the substituents on the thienyl isolation group, the conformation of the dyes, in particular the angle between the chromophore and the anchoring group, becomes more and more twisted. Surprisingly, sensitizers with poorer conjugation effects (the higher twisted conformation) achieve better photovoltaic performances, showing a contrary trend to the traditional donor‐(π‐spacer)‐acceptor dyes with a better co‐planarity. On the basis of the preceding fundamental comprehensions, an empirical method is successfully applied to a new phenyl‐based system (LI‐85 and LI‐86) to improve their performances. The systematical investigation indicates that the twisted structures can contribute to the ECB of the TiO2 film, electron lifetime and resistance at the TiO2/dye/electrolyte interface. Thereby, the efficiency of the initial LI‐80‐based cell has been dramatically improved to 2.45 times higher for LI‐86‐based cell, paving a new way for the design of better sensitizers with higher device performances. 相似文献