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1.
Lica M Schulz F Schelle I May M Just I Genth H 《Naunyn-Schmiedeberg's archives of pharmacology》2011,383(3):275-283
Toxin A (TcdA) and toxin B (TcdB) from Clostridium difficile are the causative agents of the C. difficile-associated diarrhea (CDAD) and its severe form, the pseudomembranous colitis. TcdA and TcdB both glucosylate and thereby
inactivate low molecular weight GTP-binding proteins of the Rho, Rac, and Cdc42 subfamilies. In cultured cell lines, TcdB
induces actin re-organization and bi-nucleation (“cytopathic effects”) and cell death (“cytotoxic effects”). In this study,
the role of cell cycle progression in the cytopathic and the cytotoxic effects of TcdB is evaluated by a differential analysis
of these effects in proliferating and non-proliferating cells. Density-synchronized murine fibroblasts and confluent HT29
colonocytes are exploited as cell culture models for non-proliferating cells. Cell death is analyzed in terms of a loss of
cell viability, phosphatidylserine exposure, and DNA fragmentation. In proliferating cells, TcdB blocks cell proliferation
and induces apoptotic cell death. In contrast, TcdB induces non-apoptotic cell death in non-proliferating cells. TcdB-induced
cell rounding turns out to be independent of cell cycle progression. Cell cycle progression is an important determinant in
the biological effects of TcdB. With respect to the pathology of CDAD, this study leads to the new hypothesis that necrotic
cell death of terminally differentiated colonocytes and inhibition of epithelial renewal of the colon contribute to the pathogenesis
of CDAD. 相似文献
2.
Tanaka H Hattori H Tanaka T Sakai E Tanaka N Kulkarni A Etoh H 《Journal of natural medicines》2008,62(2):228-231
A new Erythrina alkaloid, 10-hydroxy-11-oxoerysotrine (1), has been isolated from the flowers of Erythrina herbacea together with five known compounds: erytharbine (2), 10,11-dioxoerysotrine (3), erythrartine (4), erysotramidine (5) and erysotrine-N-oxide (6). The structure of the new compound was elucidated on the basis of its spectral data, including 2-D NMR and mass (MS) spectra.
The new compound is a rare C-10 oxygenated Erythrina alkaloid. The antioxidant activities of the isolated compounds 1–6 were evaluated by scavenging with peroxynitrite. 相似文献
3.
Three new ent-abietanoids, named xerophilusins XIV–XVI, and four known analogues, as well as four known chemical constituents were isolated
from the leaves of Isodon xerophilus. Their structures were elucidated by extensive spectroscopic studies, and comparison with literature data. In addition, the
cytotoxic activity of the ent-abietanoids against chronic myelogenous leukemia (K562), stomach adenocarcinoma (MKN45), and hepatocellular carcinoma (HepG2)
human cell lines was investigated and no activities were observed. 相似文献
4.
Haruka Asahina Junichi Shinozaki Kazuo Masuda Yasujiro Morimitsu Motoyoshi Satake 《Journal of natural medicines》2010,64(2):133-138
Species identification of five Dendrobium plants was conducted using phylogenetic analysis and the validity of the method was verified. Some Dendrobium plants (Orchidaceae) have been used as herbal medicines but the difficulty in identifying their botanical origin by traditional
methods prevented their full modern utilization. Based on the emerging field of molecular systematics as a powerful classification
tool, a phylogenetic analysis was conducted using sequences of two plastid genes, the maturase-coding gene (matK) and the large subunit of ribulose 1,5-bisphosphate carboxylase-coding gene (rbcL), as DNA barcodes for species identification of Dendrobium plants. We investigated five medicinal Dendrobium species, Dendrobium fimbriatum, D. moniliforme, D. nobile, D. pulchellum, and D. tosaense. The phylogenetic trees constructed from matK data successfully distinguished each species from each other. On the other hand, rbcL, as a single-locus barcode, offered less species discriminating power than matK, possibly due to its being present with little variation. When results using matK sequences of D. officinale that was deposited in the DNA database were combined, D. officinale and D. tosaense showed a close genetic relationship, which brought us closer to resolving the question of their taxonomic identity. Identification
of the plant source as well as the uniformity of the chemical components is critical for the quality control of herbal medicines
and it is important that the processed materials be validated. The methods presented here could be applied to the analysis
of processed Dendrobium plants and be a promising tool for the identification of botanical origins of crude drugs. 相似文献
5.
6.
Bioassay-guided fractionation of the MeOH extract of Suaeda glauca yielded four phenolic compounds, methyl 3,5-di-O-caffeoyl quinate (1) and 3,5-di-O-caffeoyl quinic acid (2), isorhamnetin 3-O-beta-D-galactoside (3), and quercetin 3-O-beta-D-galactoside (4). Compounds 1 and 2 were hepatoprotective against tacrine-induced cytotoxicity in human liver-derived Hep G2 cells with the EC(50) values of 72.7+/-6.2 and 117.2+/-10.5 microM, respectively. Silybin as a positive control showed an EC(50) value of 82.4+/-4.1 microM. 相似文献
7.
Rationale
±3,4-Methylenedioxymethamphetamine (MDMA, ‘ecstasy’) is a psychoactive drug that has marked effects on the serotonergic system. Serotonergic agonists are known to interact with the circadian pacemaker located in the suprachiasmatic nuclei (SCN). 相似文献8.
The aim of our study is to find functional compounds from natural resources. We focus on plants grown in tropical areas, especially Madagascar and Thailand, because they have unique flora and are expected to contain interesting compounds. We review the functional compounds of the seed kernels of Entada phaseoloides and E. rheedei and their biological activities such as anti-proliferation and melanogenesis inhibitory properties, etc. 相似文献
9.
Kim MJ Han JM Jin YY Baek NI Bang MH Chung HG Choi MS Lee KT Sok DE Jeong TS 《Archives of pharmacal research》2008,31(4):429-437
Oxidized low-density lipoprotein (oxLDL) plays a key role in the inflammatory processes of atherosclerosis. Jaceosidin isolated
from the methanolic extracts of the aerial parts of Artemisia princeps Pampanini cv. Sajabal was tested for antioxidant and anti-inflammatory activities. Jaceosidin inhibited the Cu2+-mediated LDL oxidation with IC50 values of 10.2 μM in the thiobarbituric acid-reactive substances (TBARS) assay as well as the macrophage-mediated LDL oxidation.
The antioxidant activities of jaceosidin were exhibited in the conjugated diene production, relative electrophoretic mobility,
and apoB-100 fragmentation on copper-mediated LDL oxidation. Jaceosidin also inhibited the generation of reactive oxygen species
(ROS) concerning in regulation of NF-κB signaling. And jaceosidin inhibited nuclear factor-kappa B (NF-κB) activity, nitric
oxide (NO) production, and suppressed expression of inducible nitric oxide synthase (iNOS) in lipopolysaccharide (LPS)-induced
RAW264.7 macrophages. 相似文献
10.
Twenty-eight samples of mericarps of Perilla frutescens var. frutescens were collected through fieldwork performed in Phongsali and Xieng Khouang provinces in northern Laos. No perilla samples
were collected from Savannakhet province in the south although more than 20 sites were investigated. Perilla plants are mostly
grown mixed with dry-paddy rice by slash-and-burn cultivation in Laos. The most popular local name for perilla mericarps in
the area was “Ma Nga Chan”. Weight of 1,000 grains and hardness of the mericarps were measured, and all mericarps were found
to be large (weight of 1,000 grains around 2 g) and soft (limit load weight under 300 g), which were preferred for culinary
use in Laos. The composition of the essential oils obtained from the herbaceous plants raised from the mericarps was divided
into five types, perillaketone, elemicine plus myristicine, shisofuran, piperitenon, and myristicine, and GC–MS analysis of
these Laotian perilla samples showed that they were similar to those of corresponding types of known Japanese perilla strains.
One of the shisofuran-type perilla contained large amounts of putative α-naginatene, which is likely to be an intermediate
of the biosynthesis of naginataketone. The farmers' indifference to the oil type of the leaf seems to leave Laotian perilla
as a good genetic resource for studies of the biosynthesis of oil compounds. 相似文献
11.
Muhammad A Anis I Khan A Marasini BP Choudhary MI Shah MR 《Archives of pharmacal research》2012,35(3):431-436
A new C-alkylated flavonoid (5,7-dihydroxy-3′-(4″-acetoxy-3″-methylbutyl)-3,6,4′-trimethoxyflavone (1), along with two known C-alkylated flavonoids (5,7-dihydroxy-3′-(3-hydroxymethylbutyl)-3,6,4′-trimethoxyflavone (2), 5,7,4′-trihydroxy-3′-(3-hyroxymethylbutyl)-3,6-dimethoxyflavone (3) and two new source C-alkylated flavonoids (5,7-dihydroxy-3′-(2-hydroxy-3-methyl-3-butenyl)-3,6,4′-trimethoxyflavone (4), 5,7,4′-trihydroxy-3,6-dimethoxy-3′-isoprenyl-flavone (5) were isolated from the aerial parts of Dodonaea viscosa. The structures of all compounds were established on the basis of 1D and 2D NMR spectroscopy and mass spectrometry. The isolated
compounds were evaluated for their inhibitory effect on urease and α-chymotrypsin enzyme. All the compounds (1–5) exhibited mild inhibition against urease but remained recessive in case of α-chymotrypsin. 相似文献
12.
Several new N,N-dialkyl substituted chalcones (chalconoids or benzylideneacetophenones) have been synthesized via the condensation of corresponding N,N-dialkylbenzaldehyde with various aryl methyl ketones. All the chalcones have been synthesized from readily available and cheap starting materials under environmentally benign conditions in very high yields without work up and column chromatographic purification. Synthesized compounds have been tested for their biological activity against pathogenic microorganisms such as Escherichia coli, Bacillus subtilis, and Mycobacterium smegmatis. Anti-cancer activity of these compounds has also been tested against multiple myeloma (RPMI-8226) and human mammary adenocarcinoma (MCF-7) cell lines. The most hydrophilic molecules 23 and 24 showed very good anti-cancer activity against MCF-7 cell lines at low micro-molar concentrations. All the compounds have also been evaluated for their activity against Beta-secretase 1 enzyme. One of the synthesized compounds showed Beta-secretase 1 enzyme inhibition activity at micro-molar concentration. 相似文献
13.
Kim SH Kim SH Yoon HJ Shin DH Park SS Kim YS Park JS Jee YK 《European journal of clinical pharmacology》2011,67(2):121-127
Purpose
It has been suggested that drug-metabolizing enzymes might play important roles in the development of anti-tuberculosis drug (ATD)-induced maculopapular eruption (MPE), as in ATD-induced hepatitis. We investigated the associations between the genetic polymorphisms of drug-metabolizing enzymes and ATD-induced MPE. 相似文献14.
Tetsuya Kodai Yoshinori Horiuchi Yasuhiro Nishioka Naoki Noda 《Journal of natural medicines》2010,64(2):216-218
A novel cycloartane-type triterpenoid was isolated from the fruits of Nandina domestica (Berberidaceae). The structure was characterized as 24-methylene-3-oxocycloartane 13-carboxylic acid on the basis of NMR spectroscopic data. 相似文献
15.
16.
The food/feed quality of a variety of genetically modified (GM) maize expressing Cry1Ab Bt-toxin was tested over the life-cycle of Daphnia magna, an arthropod commonly used as model organism in ecotoxicological studies. Demographic responses were compared between animals
fed GM or unmodified (UM) near isogenic maize, with and without the addition of predator smell. Age-specific data on survival
and birth rates were integrated and analysed using life tables and Leslie matrices. Survival, fecundity and population growth
rate (PGR) data generally disfavoured transgenic Bt-maize as feed for D. magna compared to animals fed the unmodified (UM) near isogenic line of maize. Decomposition of age-specific effects revealed that
the most important contributions to a reduced PGR in the GM-fed group came from both fecundity and survival differences early
in life. We conclude that juvenile and young adult stages are the most sensitive experimental units and should be prioritized
in future research. These stages are often omitted in toxicological/ecotoxicological studies and in feeding trials. 相似文献
17.
Tomoko Sano Ikue Matsumura Rie Nakamura Hiroki Yamaji Kazunori Hashimoto Osami Takeda Fumiyuki Kiuchi Tadahiro Takeda 《Journal of natural medicines》2010,64(3):257-265
Boi and its original plant Sinomenium acutum from Japan were compared with Seifuto and its botanical origins from China in terms of their internal transcribed spacer
(ITS) sequences and major chemical components. Boi, Seifuto, and their botanical origins overall showed seven variable sites
in the ITS sequence and six genotypes. Japanese S. acutum and Boi had one nucleotide variation at position 593 to show two genotypes (J1 and J2) and their heterozygote (J3). Seifuto
samples and their botanical origins, S. acutum and S. acutum var. cinereum from China, showed three genotypes (C1, C2, and C3), which did not agree with the botanical classification, indicating that
they cannot be distinguished according to their ITS sequences. All Seifuto samples from Henan market showed the same ITS genotype
(C1). The Japanese and Chinese genotypes differed in the nucleotide position 424, which can be used to distinguish the country
of origin of these materials. In the HPLC analysis of six major components, sinomenine (1), magnoflorine (2), menisperine (3), 6-O-methyllaudanosoline glucoside (4), liriodendrin (5), and menisdaurin (6), all were detected in Boi, whereas five (all except for menisdaurin) were detected in Seifuto. The main component in the
rhizome of Seifuto was sinomenine, whereas magnoflorine was the main component in the rhizome and the climbing stem of Boi.
The content of sinomenine in Seifuto was almost twice that in Boi. Although the individual content of alkaloids 1–4 differed between Boi and Seifuto, the total contents of these alkaloids were comparable between them both in the climbing
stem and rhizome. 相似文献
18.
Xiao-Zhang Yu Yu-Juan Lin Chun-Jiao Lu Xue-Hong Zhang 《Ecotoxicology (London, England)》2017,26(7):956-965
19.
Raymond?N.?Nono Elvine?P.?Nguelefack-Mbuyo Laurence?K.?Nzowa Beaudelaire?K.?Ponou Rémy?B.?Teponno Télesphore?B.?Nguelefack Luciano?Barboni Léon?A.?Tapondjou
A new C-glycosylflavone, drymaritin E (6-C-(3-keto-β-digitoxopyranosyl)-4′-O-(β-d-glucopyranosyl)-7-methoxyl-5,4′-dihydroxylflavone) 1 was isolated from the oily upper phase (SU) of the MeOH extract from aerial parts of Drymaria cordata together with two known compounds (cassiaoccidentalin A 2 and anemonin 3) and an inseparable mixture of two known C-glycosylflavones 5,4′-dihydroxy-7-methoxyflavone-6-C-(2′′-O-α-l-rhamnopyranosyl)-β-d-glucopyranoside 4a and 5,7,3′,4′-tetrahydroxyflavone-6-C-(2′′-O-α-l-rhamnopyranosyl)-β-d-glucopyranoside 4b. The alkaline hydrolysis of 3 led to a new hemisynthetic derivative, sodium anemonate (sodium 2-((1’E) 2′-sodium-carboxylate-vinyl)-5-oxo-cyclohex-1-ene carboxylate) 3a. The chemical structures were determined by spectroscopic methods (1H NMR, 13C NMR, 1H-1H COSY, HMBC, HSQC, and NOESY) and mass spectrometry (ESI–MS). C-glycosylflavones had significant free radical-scavenging activities on the radical 2,2-diphenyl-1-picrylhydrazyl (DPPH). However, SU and compounds 3 and 3a exhibited no activity. In particular, compound 1 exhibited a concentration-dependent radical scavenging activity on DPPH with EC50 of 31.43 µg/mL. 相似文献
20.
Zheng MS Lee YK Li Y Hwangbo K Lee CS Kim JR Lee SK Chang HW Son JK 《Archives of pharmacal research》2010,33(9):1307-1315
Twenty five compounds including ten triterpenes (1–3, 5–11), six flavonoids (12–15, 24, 25), five lignans (17, 18, 21–23), two butenyl clohexnone glycosides (19–20), one fructofuranoside (16) and one fatty acid (4) were isolated from the roots of Ulmus davidiana var. japonica. The structures of those compounds were identified by comparing their physicochemical and spectral data with those of published
in literatures. All the compounds were evaluated for DNA topoisomerase inhibitory activities and cytotoxicities. Among the
purified compounds, 4 and 19 showed more potent inhibitory acitivities (IC50: 39 and 19 μM, respectively) than camptothecin, as the positive control (IC50: 46 μM) against topoisomerase I. Compounds, 4, 10, 12, 19, 24 and 25 showed strong inhibitory activities toward DNA topoisomerase II (IC50: 0.1, 0.52, 0.47, 0.42, 0.17 μM and 17 nM, respectively), which were more potent than that of etoposide as positive control
(IC50: 20 μM). In A549 cell line, 5 and 6 showed cytotoxicities (IC50: 4 μM and 3 μM, respectively, with IC50 of camptothecin as positive control: 10.3 μM). In the HepG2 cell line, 3, 5 and 7 showed cytotoxicity (IC50: 4, 3 and 4 μM, respectively, with IC50 of camptothecin: 0.3 μM). Compounds 6, 12 and 23 showed cytotoxicities in the HT-29 cell line (IC50: 19, 19 and 15 μM, respectively, with IC50 of camptothecin: 2 μM). 相似文献