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21.
Plasmodium falciparum protein associated with the invasion junction contains a conserved oxidoreductase domain 总被引:2,自引:0,他引:2
Diana E. Hudson-Taylor Stephen A. Dolan Francis W. Klotz Hisashi Fujioka Masamichi Aikawa Eugene V. Koonin Louis H. Miller 《Molecular microbiology》1995,15(3):463-471
The merozoite cap protein-1 (MCP-1) of Plasmodium falciparum follows the distribution of the moving Junction during invasion of erythrocytes. We have cloned the gene encoding this protein from a cDNA library using a monoclonal antibody. The protein lacks a signal sequence and has no predicted trans-membrane domains; none of the antisera reacts with the surfaces of intact merozoites, indicating that the cap distribution is submembranous. MCP-1 is divided into three domains. The N-terminal domain includes a 52-amino-acid region that is highly conserved in a large family of bacterial and eukaryotic proteins. Based on the known functions of two proteins of this family and the pattern of amino acid conservation, it is predicted that this domain may possess oxido-reductase activity, since the active cysteine residue of this domain is invariant in all proteins of the family. The other two domains of MCP-1 are not found in any other members of this protein family and may reflect the specific function of MCP-1 in invasion. The middle domain is negatively charged and enriched in glutamate; the C-terminal domain is positively charged and enriched in lysine. By virtue of its positive charge, the C-terminal domain resembles domains in some cytoskeleton-associated proteins and may mediate the interaction of MCP-1 with cytoskeleton in Plasmodium. 相似文献
22.
Minoru Niimoto Takao Hattori Ichiji Ito Ryuichiro Tamada Kiyoshi Inokuchi Kunzo Orita Hisashi Furue Nobuya Ogawa Tomohiro Toda Motonosuke Furusawa Shigemasa Koga Isamu Hashimoto Tatsuhei Kondo Shigeru Fujimoto Yuzuru Sugiyama Osahiko Abe Masaaki Oya 《Cancer immunology, immunotherapy : CII》1984,18(1):13-18
Summary The usefulness of LMS in postoperative immunochemotherapy of gastric cancer was investigated. In compliance with the protocol, MMC was given at a dose of 20 mg on the day of gastrectomy, and an additional 10 mg on the next day IV. The patients receiving 600 mg Tegafur daily were then divided into two groups according to whether LMS was also given or not. LMS was administered for 3 days before the operation in a daily dose of 150 mg and for 1 year or more after operation according to a schedule of 3 days' administration followed by an 11-day interval. The 2-year follow-up demonstrated that in stage III patients, the LMS (+) regimen was superior to the LMS (–) regimen, since the former prolonged the relapse-free interval significantly. The survival rate for stage III disease was also significantly higher in the LMS (+) than in the LMS (–) group. There was no significant difference in the incidence of subjective or objective side-effects between two groups. The incidence of agranulocytosis was comparable in the two groups.Gastrointestinal Cancer Research Group, Japan Levamisole Research AssociationChairmen of the Gastrointestinal Cancer Research Group, Japan LMS Research AssociationController of the Gastrointestinal Cancer Research Group, Japan LMS Research AssociationMembers of the Data Collection and Analysis SubcommitteeThis study was carried out by the Gastrointestinal Cancer Research Group, Japan LMS Research Association (directed by Prof. Kiyoshi Inokuchi, Dept. of Surgery, Kyushu University and Prof. Eiro Tsubura, Dept. of Internal Medicine, Tokushima University). The results were presented in part at the 19th General Meeting of the Japanese Society for Gastroenterological Surgery in February, 1982 相似文献
23.
Hisashi Yamasaki Chiaki Katagiri Norio Yoshizaki 《Development, growth & differentiation》1990,32(1):65-72
The embryonic hatching process in the toad, Bufo japonicus , consists of two phases: rupture of the outer jelly strings at stage 20 (neural tube) and an escape from the inner jelly layers and fertilization coat (FC) of individual embryos at stage 23 (tailbud). SDS-PAGE analyses of FCs revealed that, of the eight major protein bands, two components with 58 K and 62 K in molecular weight gradually decreased from stage 18–19 on and totally disappeared at stage 22. When the FCs were treated with a hatching medium prepared by culturing denuded prehatching embryos, both 58 K and 62 K components of the FCs were solubilized, and in the solubilized materials 18 K and 31 K components appeared. Electron microscopy showed that a meshwork of filament bundles present in the FCs before stage 17 became dissociated at stage 19–20, and completely disappeared at stage 23, just before the hatching of embryos. Hatching gland cells (HGCs), an epidermal cell with numerous secretory granules, were first identified at stage 19, and underwent active secretion of the granules during stage 19–23. These results indicate that the hydrolytic degradation of 58K and 62 K components in FCs effected by the hatching enzyme constitutes the basic mechanism of embryonic hatching during both the first and second phases. 相似文献
24.
2-Acetamido-2-deoxy-5-thio-d-glucopyranose (12) has been synthesized from methyl 2-acetamido-2-deoxy-5,6-O-isopropylidene-β-d-glucofuranoside (1). Benzoylation of 1, followed by O-deisopropylidenation, gave methyl 2-acetamido-3-O-benzoyl-2-deoxy-β-d-glucofuranoside, which was converted, via selective benzoylation and mesylation, into methyl 2-acetamido-3,6-di-O-benzoyl-2-deoxy-5-O-mesyl-β-d-glucofuranoside (5). Treatment of 6, formed by the action of sodium methoxide in chloroform on 5, with thiourea gave methyl 2-acetamido-2,5,6-trideoxy-5,6-epithio-β-d-glucofuranoside (7), which was converted into the 5-thio compound 9 by cleavage of the epithio ring in 7 with potassium acetate. Alkaline treatment of 10, derived from 9 by hydrolysis, afforded the title compound. Evidence in support of the structures assigned to the new derivatives is presented. 相似文献
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27.
Toshihiro Kimura Satoshi Fukushima Etsuko Okada Haruka Kuriyama Hisashi Kanemaru Mina Kadohisa‐Tsuruta Yosuke Kubo Satoshi Nakahara Aki Tokuzumi Ikko Kajihara Katsunari Makino Azusa Miyashita Jun Aoi Takamitsu Makino Hirotake Tsukamoto Yasuharu Nishimura Takashi Inozume Rong Zhang Yasushi Uemura Satoru Senju Hironobu Ihn 《Pigment cell & melanoma research》2020,33(5):744-755
Immune checkpoint inhibitors improved the survival rate of patients with unresectable melanoma. However, some patients do not respond, and variable immune‐related adverse events have been reported. Therefore, more effective and antigen‐specific immune therapies are urgently needed. We previously reported the efficacy of an immune cell therapy with immortalized myeloid cells derived from induced pluripotent stem cells (iPS‐ML). In this study, we generated OX40L‐overexpressing iPS‐ML (iPS‐ML‐Zsgreen‐OX40L) and investigated their characteristics and in vivo efficacy against mouse melanoma. We found that iPS‐ML‐Zsgreen‐OX40L suppressed the progression of B16‐BL6 melanoma, and prolonged survival of mice with ovalbumin (OVA)‐expressing B16 melanoma (MO4). The number of antigen‐specific CD8+ T cells was higher in spleen cells treated with OVA peptide‐pulsed iPS‐ML‐Zsgreen‐OX40L than in those without OX40L. The OVA peptide‐pulsed iPS‐ML‐Zsgreen‐OX40L significantly increased the number of tumor‐infiltrating T lymphocytes (TILs) in MO4 tumor. Flow cytometry showed decreased regulatory T cells but increased effector and effector memory T cells among the TILs. Although we plan to use allogeneic iPS‐ML in the clinical applications, iPS‐ML showed the tumorgenicity in the syngeneic mice model. Incorporating the suicide gene is necessary to ensure the safety in the future study. Collectively, these results indicate that iPS‐ML‐Zsgreen‐OX40L therapy might be a new method for antigen‐specific cancer immunotherapy. 相似文献
28.
Hinako Shirakata Hisashi Nishiwaki 《Bioscience, biotechnology, and biochemistry》2020,84(10):1986-1996
ABSTRACT All eight stereoisomers of conidendrin were synthesized from (1 R,2 S,3 S)-1-(4-benzyloxy-3-methoxyphenyl)-3-(4-benzyloxy-3-methoxybenzyl)-2- hydroxymethyl-1,4-butanediol ((+)-4) and its enantiomer with high optical purity. The configurations at 4-positions of the conidendrin stereoisomers were constructed by intramolecular Friedel-Crafts reaction of protected 4. After conversion to tetrahydronaphthalene intermediate 7a, the 2- and 3-position of tetrahydronaphthalene structure 7a were converted to 3a- and 9a-position of (+)-α-conidendrin (3a), respectively. By the epimerization process of 2- or 3-position of 7a, the other diastereomers were obtained. All enantiomers were also synthesized from (?)-4. 相似文献
29.
Hinaka Yoshida Hisashi Takeda Daigo Wakana Fumihiko Sato 《Bioscience, biotechnology, and biochemistry》2020,84(6):1274-1284
ABSTRACTBerberine (BBR) is a protoberberine alkaloid extracted from plants such as Coptis japonica (Ranunculaceae). In a previous report, we demonstrated the existence of a 11-hydroxylation pathway employed by BBR-utilizing bacteria for metabolism of BBR. In the present study, we report the identification of the genes brhA, brhB, and brhC as encoding a multicomponent BBR 11-hydroxylase in Burkholderia sp. strain CJ1. BrhA is belonging to the Rieske non-heme iron oxygenase (RO) family, a class of enzymes known to catalyze the first step in bacterial aromatic-ring hydroxylation. We further demonstrate that BrhA activity requires BrhB (ferredoxin reductase) and BrhC (ferredoxin) as electron transport chain components. A BLAST search revealed that BrhA exhibits 38% and 33% sequence identity to dicamba O-demethylase (DdmC; AY786443) and chloroacetanilide herbicides N-dealkylase (CndA; KJ461679), respectively. To our knowledge, this work represents the first report of a bacterial oxygenase catalyzing the metabolism of a polycyclic aromatic-ring alkaloid.Abbreviations: BBR: berberine; D-BBR: demethyleneberberine; H-BBR: 11-hydroxyberberine; HD-BBR: 11-hydroxydemethyleneberberine; HDBA: 2-hydroxy-3,4-dimethoxybenzeneacetic acid; PAL: palmatine; H-PAL: 11-hydroxypalmatine; BRU: berberrubine; Fd: ferredoxin; FdR: ferredoxin reductase; ETC: electron transport chain 相似文献
30.
The development of molecular diagnostic tools to achieve individualized medicine requires identifying predictive biomarkers associated with subgroups of individuals who might receive beneficial or harmful effects from different available treatments. However, due to the large number of candidate biomarkers in the large‐scale genetic and molecular studies, and complex relationships among clinical outcome, biomarkers, and treatments, the ordinary statistical tests for the interactions between treatments and covariates have difficulties from their limited statistical powers. In this paper, we propose an efficient method for detecting predictive biomarkers. We employ weighted loss functions of Chen et al. to directly estimate individual treatment scores and propose synthetic posterior inference for effect sizes of biomarkers. We develop an empirical Bayes approach, namely, we estimate unknown hyperparameters in the prior distribution based on data. We then provide efficient screening methods for the candidate biomarkers via optimal discovery procedure with adequate control of false discovery rate. The proposed method is demonstrated in simulation studies and an application to a breast cancer clinical study in which the proposed method was shown to detect the much larger numbers of significant biomarkers than existing standard methods. 相似文献