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241.
Tsung-Hung Chen Wu-Fu Chen Zhi-Hong Wen Mei-Chin Lu Wei-Hsien Wang Jan-Jung Li Yang-Chang Wu Ping-Jyun Sung 《Marine drugs》2014,12(4):2144-2155
Five new 7α-hydroxyeunicellin-based diterpenoids, designated as cladieunicellins M–Q (1–5), were isolated from a Formosan octocoral Cladiella sp. The structures of 1–5 were elucidated on the basis of spectroscopic methods and by comparison of the data with those of the related metabolites. Cytotoxicity of metabolites 1–5 against the human leukemia Molt 4 and HL 60 is also described. Among them, compounds 1, 3 and 5 exhibited moderate cytotoxicity toward Molt 4 cells with IC50 values 16.43, 14.17 and 15.55 μM, respectively. Preliminary SAR (structure activity relationship) information was obtained from these compounds and their analogues. 相似文献
242.
Chen YH Tai CY Su YD Chang YC Lu MC Weng CF Su JH Hwang TL Wu YC Sung PJ 《Marine drugs》2011,9(6):934-943
Two new 11-hydroxyeunicellin diterpenoids, cladieunicellin F (1) and (-)-solenopodin C (2), were isolated from an Indonesian octocoral Cladiella sp. The structures of eunicellins 1 and 2 were established by spectroscopic methods, and eunicellin 2 was found to be an enantiomer of the known eunicellin solenopodin C (3). Eunicellin 2 displayed inhibitory effects on the generation of superoxide anion and the release of elastase by human neutrophils. The previously reported structures of two eunicellin-based compounds, cladielloides A and B, are corrected in this study. 相似文献
243.
The influences of a series of new azo direct dyes including copper-complexes based on benzidine congeners, 2,2′-dimethyl-5,5′-dipropoxybenzidine
and 5,5′-dipropoxybenzidine, were examined using microorganism, Daphnia magna. The purpose of the research described in this
paper was to use bioassays with daphnids to determine the aquatic toxicity of new azo dyes in which copper was incorporated.
The results clearly show that copper has negative effects to aquatic ecosystem as expected. The study also suggested that
the assay with Daphnia magna was an excellent method to evaluate the influences of dyes to the aquatic environment. 相似文献
244.
Kang MR Kim HM Kang JS Lee K Lee SD Hyun DH In MJ Park SK Kim DC 《Plant foods for human nutrition (Dordrecht, Netherlands)》2011,66(2):101-106
This study was performed to elucidate the anticancer mechanism of a lipid-soluble ginseng extract (LSGE) by analyzing induction
of apoptosis and arrest of cell cycle progression using the NCI-H460 human lung cancer cell line. Proliferation of NCI-H460
cells was potently inhibited by LSGE in a dose-dependent manner. The cell cycle arrest at the G0/G1 phase in NCI-H460 cells
was induced by LSGE. The percentage of G0/G1 phase cells significantly increased, while that of S phase cells decreased after
treatment with LSGE. The expression levels of cyclin-dependent kinase2 (CDK2), CDK4, CDK6, cyclin D3 and cyclin E related
to G0/G1 cells progression were also altered by LSGE. In addition, LSGE-induced cell death occurred through apoptosis, which
was accompanied by increasing the activity of caspases including caspase-8, caspase-9 and caspase-3. Consistent with enhancement
of caspase activity, LSGE increased protein levels of cleaved caspase-3, caspase-8, caspase-9, and poly-ADP-ribose polymerase
(PARP). These apoptotic effects of LSGE were inhibited by the pan-caspase inhibitor Z-VAD-fmk. These findings indicate that
LSGE inhibits NCI-H460 human lung cancer cell growth by cell cycle arrest at the G0/G1 phase and induction of caspase-mediated
apoptosis. 相似文献
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248.
H9N2 influenza viruses isolated from poultry in Korean live bird markets continuously evolve and cause the severe clinical signs in layers 总被引:5,自引:0,他引:5
H9N2 influenza viruses are endemic in many Asian countries. We demonstrated that H9N2 influenza viruses isolated from poultry in Korean live bird markets are genetically changing and could cause the clinical signs in layers. Genetic analysis showed that Korean avian H9N2 influenza viruses are distinct from H9N2 influenza viruses circulating in poultry in China and Hong Kong. When we infected layers with H9N2 isolates, layers showed about 30% mortality and the reduction of egg productions. Considering that H9N2 influenza virus is one of potential pandemic candidates, the continuous surveillance is needed to monitor avian H9N2 influenza viruses for the poultry industry and humans. 相似文献
249.
In this study, an in vitro nitric oxide (*NO)-generating system was used to investigate the *NO-scavenging effects of methanolic extracts of white ginseng (Panax ginseng C.A. Meyer), red ginseng, and sun ginseng and several ginsenosides and phenolic compounds. Sun ginseng extract showed the strongest activity among the three ginseng extracts. None of the ginsenosides used in this experiment showed *NO-scavenging activity, but the phenolic compounds, such as p-coumaric and vanillic acids, and maltol inhibited *NO production in a concentration-dependent manner. Moreover, maltol levels markedly increased by heat processing. Therefore, the enhanced *NO-scavenging activity of ginseng by heat processing was closely related to phenolic acids and the increased content of maltol. 相似文献
250.
Hsieh CW Liu LK Yeh SH Chen CF Lin HI Sung HY Wang AY 《Journal of agricultural and food chemistry》2006,54(8):3101-3107
Three Bo beta fruct cDNAs encoding acid invertases were cloned from shoots of the green bamboo Bambusa oldhamii. On the basis of the amino acid sequences of their products and phylogenetic analyses, Bo beta fruct1 and Bo beta fruct2 were determined to encode cell wall invertases, whereas Bo beta fruct3encodes a vacuolar invertase. The recombinant proteins encoded by Bo beta fruct2 and Bo beta fruct3 were produced in Pichia pastoris and purified to near homogeneity using ammonium sulfate fractionation and immobilized metal affinity chromatography. The pH optima, pI values, and substrate specificities of the isolated enzymes were consistent with those of plant cell wall or vacuolar invertases. The growth-dependent expression of Bo beta fruct1 and Bo beta fruct2 in the base regions of shoots underscores their roles in sucrose unloading and providing substrates for shoot growth. Its high sucrose affinity suggests that the Bo beta fruct2-encoded enzyme is important for maintaining the sucrose gradient between source and sink organs, while the predominant expression of Bo beta fruct3 in regions of active cell differentiation and expansion suggests functions in osmoregulation and cell enlargement. 相似文献