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991.
992.
993.
A simple and rapid detection system for wheat allergen was developed based on a luminescence immunoassay with a continuous flow system. Wheat allergen and alkaline phosphatase conjugated IgE (ALP-IgE) was separated from free ALP-IgE on the basis of a difference in isoelectric point, using with an anion exchange resin. Luminescence output of the assay correlated linearly with the concentration of allergen in the range of 1-100 µg/ml. Reuse of free ALP-IgE was possible. 相似文献
994.
Pascal Béguin Kazuaki Nagashima Ramasubbu N. Mahalakshmi Réjan Vigot Atsuko Matsunaga Takafumi Miki Mei Yong Ng Yu Jin Alvin Ng Chiaw Hwee Lim Hock Soon Tay Le-Ann Hwang Dmitri Firsov Bor Luen Tang Nobuya Inagaki Yasuo Mori Susumu Seino Thomas Launey Walter Hunziker 《The Journal of cell biology》2014,205(2):233-249
Voltage-gated calcium channels (VGCCs) are key regulators of cell signaling and Ca2+-dependent release of neurotransmitters and hormones. Understanding the mechanisms that inactivate VGCCs to prevent intracellular Ca2+ overload and govern their specific subcellular localization is of critical importance. We report the identification and functional characterization of VGCC β-anchoring and -regulatory protein (BARP), a previously uncharacterized integral membrane glycoprotein expressed in neuroendocrine cells and neurons. BARP interacts via two cytosolic domains (I and II) with all Cavβ subunit isoforms, affecting their subcellular localization and suppressing VGCC activity. Domain I interacts at the α1 interaction domain–binding pocket in Cavβ and interferes with the association between Cavβ and Cavα1. In the absence of domain I binding, BARP can form a ternary complex with Cavα1 and Cavβ via domain II. BARP does not affect cell surface expression of Cavα1 but inhibits Ca2+ channel activity at the plasma membrane, resulting in the inhibition of Ca2+-evoked exocytosis. Thus, BARP can modulate the localization of Cavβ and its association with the Cavα1 subunit to negatively regulate VGCC activity. 相似文献
995.
Shigeki Matsunaga 《Molecular simulation》2015,41(10-12):913-917
The molecular dynamics simulations have been performed for the sodium nitrate solution at various concentrations in the 1.1 mol% sodium chloride aqueous solution, which is a model of the sea water. The structure, the velocity correlation functions and the frequency-dependent diffusion coefficients have been obtained. The share viscosity has also been obtained at various concentrations using the Green–Kubo formula, which agrees well with the experimental data. The complex formation and the microscopic charge neutrality in the solution have been discussed in relation to the ionic conductivity estimated by the Nernst–Einstein relation. 相似文献
996.
Matsunaga N Kaku T Ojida A Tanaka T Hara T Yamaoka M Kusaka M Tasaka A 《Bioorganic & medicinal chemistry》2004,12(16):4313-4336
A series of 1- and 4-(2-naphthylmethyl)-1H-imidazoles (3 and 4) has been synthesized and evaluated as C(17,20)-lyase inhibitors. Several 6-methoxynaphthyl derivatives showed potent C(17,20)-lyase inhibition, suppression of testosterone biosynthesis in rats and reduction in the weight of prostate and seminal vesicles in rats, whereas most of these compounds increased the liver weight after consecutive administrations. The effect on the liver weight was removed by incorporation of a hydroxy group and an isopropyl group at the methylene bridge, as seen in (S)-28d and (S)-42. Selectivity for C(17,20)-lyase over 11beta-hydroxylase is also discussed, and (S)-42 was found to be a more than 260-fold selective inhibitor. Furthermore, (S)-42 showed a potent suppression of testosterone biosynthesis after a single oral administration in monkeys. These data suggest that (S)-42 may be a promising agent for the treatment of androgen-dependent prostate cancer. 相似文献
997.
Masuzawa Toshiyuki Suzuki Teruyuki Seki Kayoko Kosugi Tsuyoshi Hibi Yuriko Yamamoto Mineko Takada Jitsuya Matsushita Rokuji Yanada Mitsuru 《Biological trace element research》1999,(1):331-342
Phytoplankton samples were collected during spring bloom of diatoms from three coastal areas of Japan using a NORPAC P-25
net (25-Μm opening) with a NGG52 prenet (335-Μm opening), and 25 major and trace elements have been analyzed by INAA. Concentration
ranges of analyzed phytoplankton samples are much wider than the concentration ranges compiled by Bowen (1979) except for
As, and data of marine phytoplankton samples for Br, Sb, Hf, Sc, La, Ce, Sm, and Eu were not included in the compilation.
The 25 analyzed elements have been categorized into three groups: elements showing positive correlation with Br, positive
correlation with Al, and no positive correlation with Br or Al. The marine phytoplankton samples have been plotted on a Masuzawa-Koyama-Terazaki
(MKT) plot and it proved that the MKT plot is applicable to marine phytoplankton samples. 相似文献
998.
Molecular analysis of the gene of the alpha 1-antitrypsin deficiency variant, Mnichinan. 总被引:2,自引:1,他引:2 下载免费PDF全文
E Matsunaga S Shiokawa H Nakamura T Maruyama K Tsuda Y Fukumaki 《American journal of human genetics》1990,46(3):602-612
Mnichinan, a variant of alpha 1-antitrypsin (alpha 1-AT) was detected in a Japanese individual with serum alpha 1-AT deficiency (18 mg/dl), associated with aggregated alpha 1-AT molecules in the hepatocytes. Cloning and sequencing of the 10,627-bp-long region containing the Mnichinan gene and the normal M1(Val213) alpha 1-AT gene revealed all five exons of the Mnichinan gene to be identical with the M1(Val213) alpha 1-AT gene, except for two changes: a TTC trinucleotide deletion in the codon for amino acid Phe52 and a G-A substitution, by which the normal Gly148 (GGG) became Arg148 (AGG). Dot blot analysis of the polymerase chain-reaction-amplified DNA derived from the proband and other family members showed both mutations to be associated with an alpha 1-AT deficiency phenotype. Ninety-eight alpha 1-AT alleles were all negative for both changes. Comparison of the region, except for five exons between the Mnichinan and M1(Val213) genes, demonstrated one base difference in the 5' flanking region and 14 base changes in the introns. All exon-intron junctions were identical, and base changes in the 5' flanking region did not seem significant. The G-A substitution in codon 148 of the Mnichinan gene could not be responsible for the alpha 1-AT deficiency phenotype because Arg- and not Gly- was located at the corresponding position of the protein C inhibitor belonging to the serine protease inhibitor superfamily. The deletion of Phe52 may cause the newly synthesized alpha 1-AT protein to aggregate, resulting in alpha 1-AT deficiency. Comparison of the alpha 1-AT gene sequences available indicated that the C-T substitution at the CpG dinucleotide has an important role in generation of variants and nucleotide changes in the noncoding regions of the alpha 1-AT gene. 相似文献
999.
T G LaCour C Guo S Ma J U Jeong M R Boyd S Matsunaga N Fusetani P L Fuchs 《Bioorganic & medicinal chemistry letters》1999,9(17):2587-2592
Analogues 12'beta-hydroxycephalostatin 1 (9), 7'-deoxyritterazine G (10), and 14-epi-7'-deoxyritterazine B (11) were prepared via our protocol for unsymmetrical pyrazine synthesis. Cytotoxicity against human tumors was also determined for the first time for ritterazines, with femtomolar potency and a high correlation to cephalostatins observed. The SAR of these and related compounds provide insight into the importance of topography and certain chemical functionality in the B-D and B'-D' rings of cephalostatin type antineoplastics. 相似文献
1000.