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排序方式: 共有378条查询结果,搜索用时 11 毫秒
71.
Matsuda H Yoshida K Miyagawa K Nemoto Y Asao Y Yoshikawa M 《Bioorganic & medicinal chemistry letters》2006,16(6):1567-1573
The methanolic extract and its alkaloid fraction from the rhizomes of Nuphar pumilum showed cytotoxic effects on human leukemia cell (U937), mouse melanoma cell (B16F10), and human fibroblast (HT1080). Dimeric sesquiterpene thioalkaloids with the 6-hydroxyl group (6-hydroxythiobinupharidine, 6,6'-dihydroxythiobinupharidine, 6-hydroxythionuphlutine B) showed substantial cytotoxic activity at a concentration of 10 microM, but dimeric sesquiterpene thioalkaloids lacking the 6-hydroxyl group (thiobinupharidine, thionuphlutine B, 6'-hydroxythionuphlutine B, neothiobinupharidine, thionuphlutine B beta-sulfoxide, and neothiobinupharidine beta-sulfoxide) and monomeric sesquiterpene alkaloids (nupharidine, 7-epideoxynupharidine, and nupharolutine) showed weak activity. Next, apoptosis-inducing activity of a principal active constituent, 6-hydroxythiobinupharidine, on U937 was examined using morphological observation and DNA fragmentation assay (TUNEL method). Apoptosis of U937 was immediately observed within 1 h after treatment of 6-hydroxythiobinupharidine at 2.5-10 microM. 相似文献
72.
Lim S Ashida H Watanabe R Inai K Kim YS Mukougawa K Fukuda H Tomizawa K Ushiyama K Asao H Tamoi M Masutani H Shigeoka S Yodoi J Yokota A 《Plant molecular biology》2011,76(3-5):335-344
The production of human therapeutic proteins in plants provides opportunities for low-cost production, and minimizes the risk of contamination from potential human pathogens. Chloroplast genetic engineering is a particularly promising strategy, because plant chloroplasts can produce large amounts of foreign target proteins. Oxidative stress is a key factor in various human diseases. Human thioredoxin 1 (hTrx1) is a stress-induced protein that functions as an antioxidant against oxidative stress, and overexpression of hTrx1 has been shown to suppress various diseases in mice. Therefore, hTrx1 is a prospective candidate as a new human therapeutic protein. We created transplastomic lettuce expressing hTrx1 under the control of the psbA promoter. Transplastomic plants grew normally and were fertile. The hTrx1 protein accumulated to approximately 1% of total soluble protein in mature leaves. The hTrx1 protein purified from lettuce leaves was functionally active, and reduced insulin disulfides. The purified protein protected mouse insulinoma line 6 cells from damage by hydrogen peroxide, as reported previously for a recombinant hTrx1 expressed in Escherichia coli. This is the first report of expression of the biologically active hTrx1 protein in plant chloroplasts. This research opens up possibilities for plant-based production of hTrx1. Considering that this expression host is an edible crop plant, this transplastomic lettuce may be suitable for oral delivery of hTrx1. 相似文献
73.
Mayumi Kamada Sumitaka Hase Kengo Sato Atsushi Toyoda Asao Fujiyama Yasubumi Sakakibara 《PloS one》2014,9(10)
De novo microbial genome sequencing reached a turning point with third-generation sequencing (TGS) platforms, and several microbial genomes have been improved by TGS long reads. Bacillus subtilis natto is closely related to the laboratory standard strain B. subtilis Marburg 168, and it has a function in the production of the traditional Japanese fermented food “natto.” The B. subtilis natto BEST195 genome was previously sequenced with short reads, but it included some incomplete regions. We resequenced the BEST195 genome using a PacBio RS sequencer, and we successfully obtained a complete genome sequence from one scaffold without any gaps, and we also applied Illumina MiSeq short reads to enhance quality. Compared with the previous BEST195 draft genome and Marburg 168 genome, we found that incomplete regions in the previous genome sequence were attributed to GC-bias and repetitive sequences, and we also identified some novel genes that are found only in the new genome. 相似文献
74.
Akira Kuninaka Masao Kumagai Kazuo Fujiyama Masaru Ogura Shinji Sakata Seishiro Yonei 《Bioscience, biotechnology, and biochemistry》2013,77(6):1437-1439
Substance B, the major component, isolated from rice plant treated with probenzaole and inoculated, having anti-conidial germination activity against blast fungus, was found to be a mixture of fatty acids, including palmitic acid, linoleic acid and linolenic acid. The main compound of substance B was linolenic acid, having strong anti-conidial germination activity. It was determined as α-linolenic acid by gas chromatographic analysis. The minor components showed little or no anti-conidial germination activity. 相似文献
75.
Paiotti AP Miszputen SJ Oshima CT Artigiani Neto R Ribeiro DA Franco M 《Journal of molecular histology》2011,42(5):443-450
Crohn′s disease (CD) is associated with gut barrier dysfunction. Tumour necrosis factor-α (TNF-α) plays an important role
into the pathogenesis of several inflammatory diseases because its expression is increased in inflamed mucosa of CD patients.
Anti-TNF therapy improves significantly mucosal inflammation. Thus, this study aimed to evaluate the effect of Etanercept
(ETC), a tumour necrosis factor alpha (TNF-α) antagonist on the 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced experimental
colitis. A total of 18 Wistar rats were randomized into four groups, as follows: (1) Sham: sham induced-colitis; (2) TNBS:
non-treated induced-colitis; (3) ETC control; (4) ETC-treated induced-colitis. Rats from group 4 presented significant improvement
either of macroscopic or of histopathological damage in the distal colon. The gene expression of TNF-α mRNA, decreased significantly
in this group compared to the TNBS non-treated group. The treatment with etanercept attenuated the colonic damages and reduced
the inflammation caused by TNBS. Taken together, our results suggest that ETC attenuates intestinal colitis induced by TNBS
in Wistar rats by TNF-α downregulation. 相似文献
76.
Molecular survey of Babesia microti, Ehrlichia species and Candidatus neoehrlichia mikurensis in wild rodents from Shimane Prefecture, Japan 总被引:1,自引:0,他引:1
Tabara K Arai S Kawabuchi T Itagaki A Ishihara C Satoh H Okabe N Tsuji M 《Microbiology and immunology》2007,51(4):359-367
A significant number of patients are diagnosed with "fevers of unknown origin" (FUO) in Shimane Prefecture in Japan where tick-borne diseases are endemic. We conducted molecular surveys for Babesia microti, Ehrlichia species, and Candidatus Neoehrlichia mikurensis in 62 FUO cases and 62 wild rodents from Shimane Prefecture, Japan. PCR using primers specific for the Babesia 18S small-subunit rRNA (rDNA) gene and Anaplasmataceae groESL amplified products from 45% (28/62) and 25.8% (16/62) of captured mice, respectively. Of the 28 18S rDNA PCR positives, 23 and five samples were positive for Hobetsu- and Kobe-type B. microti, respectively. In contrast, of the 16 groESL PCR positives, eight, one and seven samples were positive for Ehrlichia muris, Ehrlichia sp. HF565 and Candidatus N. mikurensis, respectively. Inoculation of selected blood samples into Golden Syrian hamsters indicated the presence of Hobetsu- and Kobe-type B. microti in four and one sample, respectively. Isolation of the latter strain was considered important as previous studies suggested that the distribution of this type was so far confined to Awaji Island in Hyogo Prefecture, where the first case of transfusion-associated human babesiosis originated. DNA samples from 62 FUO human cases tested negative for B. microti 18S rDNA gene, Anaplasmataceae groESL gene, Rickettsia japonica 17K genus-common antigen gene and Orientia tsutsugamushi 56K antigen gene by PCRs. We also conducted seroepidemiological surveys on 62 human sera collected in Shimane Prefecture from the FUO patients who were suspected of carrying tick-borne diseases. However, indirect immunofluorescent antibody tests using B. microti- and E. muris-infected cells detected IgG against E. muris in only a single positive sample. This study demonstrates the presence of several potentially important tick-borne pathogens in Shimane Prefecture and suggests the need for further study on the causative agents of FUOs. 相似文献
77.
Ana Carolina Cuzzuol Fracalossi Sandra Regina Miranda Celina Tijuko Fujiyama Oshima Marcello Franco Daniel Araki Ribeiro 《Journal of molecular histology》2010,41(1):19-25
Matrix metalloproteinases (MMPs) are implicated in a wide range of physiological and pathological processes, including morphogenesis,
wound healing, angiogenesis, inflammation, and cancer. The purpose of this study was to characterize the role of MMPs as depicted
by the expression of MMP-2 and MMP-9 during 4-nitroquinoline 1-oxide-induced rat tongue carcinogenesis. Male Wistar rats were
distributed into three groups of 10 animals each and treated with 4-nitroquinoline 1-oxide solution at 50 ppm through their
drinking water for 4, 12, and 20 weeks. Ten animals were used as control group. No histopathological abnormalities were induced
in the epithelium after 4 weeks of carcinogen exposure; however, immunoexpression of MMP-2 was noticed. The same picture occurred
to MMP-9, in which positive expression was detected for this immunomarker. MMP-2 and MMP-9 showed positive expression either
in pre-neoplastic lesions at 12 weeks following carcinogen exposure or in well-differentiated squamous cell carcinoma induced
after 20 weeks of treatment with 4NQO. Taken together, our results support the belief that MMP-2 and MMP-9 play important
role during malignant transformation and conversion of oral mucosa as assessed by immunohistochemistry. 相似文献
78.
Kazuhito Fujiyama Hideaki Maki Shinichi Kinoshita Toshiomi Yoshida 《FEMS microbiology letters》1995,126(1):19-23
Abstract The plasmid pAL205 encodes an alginate lyase gene of Pseudomonas sp. OS-ALG-9, fused in frame to the β-galactosidase α-peptide gene. The alginate lyase (Aly) expressed in Escherichia coli (pAL205) was significantly secreted into the medium by the addition of glycine. The extracellular enzyme isolated from the culture of E. coli JM109 (pAL205) was purified over 15 000-fold by successive chromatography and subjected to amino acid sequence analysis. The sequence determined was identical to that of the intracellular protein. Since the activity and molecular size of the extracellular Aly is identical to the intracellular protein and to the Aly isolated from Pseudomonas , the glycine does not affect or modify the Aly during its leakage into the medium. 相似文献
79.
Individual variation in two species of host plants (thistle,Cirsium kamtschaticum, and blue cohosh,Caulophyllum robustum) of the herbivorous ladybird beetleEpilachna pustulosa was examined under laboratory conditions for their acceptability to adult beetles as a food resource, for adult preference
and for larval performance. When clones of these plants were subjected to non-choice tests using posthibernating female beetles,
there was found to be significant intraspecific variation among clones in terms of their acceptability, but interspecific
variation was not detected. Significant intraspecific as well as interspecific variation were frequently detected in the two
host plants when clones of these plants were subjected to choice tests using posthibernating female beetles; the magnitude
of interspecific plant variation for beetle preference is not necessarily larger than that of intraspecific plant variation.
Individual variation across plant species with respect to beetle larval performance was also significant. A positive correlation
between adult preference and larval performance is suggested across the two taxonomically remote host plant species, thistle
and blue cohosh, although this needs further investigation. 相似文献
80.
Moran D.G. Yoshida S. Fujiyama K. Seki T. Yoshida T. 《World journal of microbiology & biotechnology》1997,13(3):265-267
A truncated Man9-mannosidase gene and a full-length -1,4-galactosyltransferase gene were isolated from human kidney and placenta cDNAs, respectively. Both genes were cloned in plasmid pMAL-c2 to produce fusions with maltose-binding protein. Fusion products were purified by affinity chromatography. Purified enzymes were assayed using pyridyl-amino labelled oligosaccharides as substrates and analysed by HPLC. 相似文献