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91.
92.
Minoru Nakao Antti Lavikainen Tetsuya Yanagida Akira Ito 《International journal for parasitology》2013,43(12-13):1017-1029
Echinococcosis is a serious helminthic zoonosis in humans, livestock and wildlife. The pathogenic organisms are members of the genus Echinococcus (Cestoda: Taeniidae). Life cycles of Echinococcus spp. are consistently dependent on predator–prey association between two obligate mammalian hosts. Carnivores (canids and felids) serve as definitive hosts for adult tapeworms and their herbivore prey (ungulates, rodents and lagomorphs) as intermediate hosts for metacestode larvae. Humans are involved as an accidental host for metacestode infections. The metacestodes develop in various internal organs, particularly in liver and lungs. Each metacestode of Echinococcus spp. has an organotropism and a characteristic form known as an unilocular (cystic), alveolar or polycystic hydatid. Recent molecular phylogenetic studies have demonstrated that the type species, Echinococcus granulosus, causing cystic echinococcosis is a cryptic species complex. Therefore, the orthodox taxonomy of Echinococcus established from morphological criteria has been revised from the standpoint of phylogenetic systematics. Nine valid species including newly resurrected taxa are recognised as a result of the revision. This review summarises the recent advances in the phylogenetic systematics of Echinococcus, together with the historical backgrounds and molecular epidemiological aspects of each species. A new phylogenetic tree inferred from the mitochondrial genomes of all valid Echinococcus spp. is also presented. The taxonomic nomenclature for Echinococcus oligarthrus is shown to be incorrect and this name should be replaced with Echinococcus oligarthra. 相似文献
93.
Keisuke Maruyama Masaharu Nakamura Shusuke Tomoshige Kazuyuki Sugita Makoto Makishima Yuichi Hashimoto Minoru Ishikawa 《Bioorganic & medicinal chemistry letters》2013,23(14):4031-4036
Our multi-template approach for drug discovery, focusing on protein targets with similar fold structures, has yielded lead compounds for various targets. We have also shown that a diphenylmethane skeleton can serve as a surrogate for a steroid skeleton. Here, on the basis of those ideas, we hypothesized that the diphenylmethane derivative bisphenol A (BPA) would bind to the ligand-binding domain of estrogen receptors (ERs) in a similar manner to estradiol and act as a steroid surrogate. To test this idea, we synthesized a series of BPA analogs and evaluated their structure-activity relationships, focusing on agonistic/antagonistic activities at ERs and ERα/ERβ subtype selectivity. Among the compounds examined, 18 was found to be a potent ERα-antagonist with high selectivity over ERβ and androgen receptor under our assay conditions. A computational docking study suggested that 18 would bind to the antagonistic conformation of ERα. ERα-selective antagonists, such as 18, are candidate agents for treatment of breast cancer. 相似文献
94.
Minoru Tanaka Xin Li Hidemasa Hikawa Takafumi Suzuki Katsuhiko Tsutsumi Masashi Sato Osamu Takikawa Hideharu Suzuki Yuusaku Yokoyama 《Bioorganic & medicinal chemistry》2013,21(5):1159-1165
Indoleamine 2,3-dioxygenase (IDO) plays a significant role in several disorders such as Alzheimer’s disease, age-related cataracts and tumors. A series of novel tryptoline derivatives were synthesized and evaluated for their inhibitory activity against IDO. Substituted tryptoline derivatives (11a, 11c, 11e, 12b and 12c) were demonstrated to be more potent than known inhibitor MTH-Trp. Suzuki–Miyaura cross-coupling reaction of 11a–d with phenylboronic acid proceeded in high yields. In most cases, C5 and C6 substitutions on the corresponding indole ring were well tolerated. The tryptoline derivative 11c is a promising chemical lead for the discovery of novel IDO inhibitors. 相似文献
95.
96.
DNA-synthesis stimulatory activity was found in some tryptic fragments of human /¡-casein by using BALB/c3T3 cells, and two of them were identified as the /¡-casein fragments of Arg[l] to Lys[18] (/¡-CN(f 1 -18)) and of Gln[105] to Lys[l 17] (/¡-CN(fl05 -117)). 相似文献
97.
Ichiro Tomida Hiroshi Kayahara Ryozo Iriye 《Bioscience, biotechnology, and biochemistry》2013,77(11):2549-2555
The degree of racemization in the several activated ester methods of the peptide synthesis was measured in using the critical racemization test, Pro-Val+Pro, with help of gas chromatography. The results were compared with that in the coupling reaction, Leu-Phe+Val, in which no racemization had been reported in the corresponding reaction conditions by F. Weygand et al., when the activated dipeptide esters had been prepared from Z-Leu+Phe-activated esters. The significantly higher racemization was observed in the methods of N-hydroxypiperidine ester and thiophenyl ester, even when the activated dipeptide esters were prepared from Z-Pro+Val-activated esters. On the other hand, almost no racemization was observed in the N-hydroxysuccinimide ester and p-nitrophenyl ester methods. A great extent of the racemization was detected when the activated dipeptide esters were prepared directly from Z-Pro-Val-OH. 相似文献
98.
Synthesis of β-tubanol (VIa) was achieved by the bromination of dihydro-β-tubanol acetate (VIIb) followed by dehydrobromination and the subsequent hydrolysis. 2,2-Dimethyl-5-hydroxy-chromanone as well as its derivatives (IV) and the corresponding chromanols (V) and chromans (VII) were also prepared. 相似文献
99.
Rikisaku Suemitsu Minoru Nakajima Makoto Hiura 《Bioscience, biotechnology, and biochemistry》2013,77(2):100-102
Macrosporin monoluethylether was synthesized by means of condensation between α-resorcylic acid (I) and 3-methoxy-p-toluic acid (II) with the use of conc. sulfuric acid and boric anhydride.From this result macrosporin C16H12O5, a metabolic product of Macrosporium Porri Elliott, was established to be 3,5-dihydroxy-7-methoxy-2-methyl anthraquinone (A). 相似文献
100.
Akira Hasegawa Daikichi Nishimura Takashi Kurokawa Minoru Nakajima 《Bioscience, biotechnology, and biochemistry》2013,77(10):1773-1776
Paromamine and its related compounds were synthesized by a modified Königs-Knorr reaction of 3,4,6-tri-O-acetyl-2-(2′,4′-dinitroanilno)-α-d-glucopyranosyl bromide with isopropylidene derivatives of 2-deoxystreptamine, streptamine and dihydroconduramine F–4. The condensed products were isolated as their poly N-acetyl derivatives and proved to have α-configuration by PMR spectroscopy in D2O. 相似文献