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101.
Zaghdane H Boyd M Colucci J Simard D Berthelette C Leblanc Y Wang Z Houle R Lévesque JF Molinaro C Hamel M Stocco R Sawyer N Sillaots S Gervais F Gallant M 《Bioorganic & medicinal chemistry letters》2011,21(11):3471-3474
A new series of indole amide acting as hCRTH2 receptor ligands had been explored and are described herein. Several amide derivatives displaying low nanomolar activity in hCRTH2 binding and whole blood assays were identified. They were found to behave as a full antagonists, exhibiting good selectivity over related prostaglandin receptors. Also, prototypical compounds in this novel series which displayed acceptable CYP profiles and were orally bioavailable in rats were identified. 相似文献
102.
Burchak ON Pihive EL Maigre L Guinchard X Bouhours P Jolivalt C Schneider D Maurin M Giglione C Meinnel T Paris JM Denis JN 《Bioorganic & medicinal chemistry》2011,19(10):3204-3215
A collection of 3-substituted indole derivatives was prepared using nucleophilic addition of indoles to nitrones. The compounds were then tested for their antibacterial activity against almost thirty bacterial strains representative of common human pathogens. Two types of indolic molecules inhibit the growth of Staphylococcus aureus, including MRSA and VISA strains, with MIC values ranging from 8 to 16 mg/L. 相似文献
103.
Mazzoli A Carlotti B Bonaccorso C Fortuna CG Mazzucato U Miolo G Spalletti A 《Photochemical & photobiological sciences》2011,10(11):1830-1836
The relaxation properties of the excited states of three iodides of trans-1,2-diarylethene analogues (where one aryl group is a methylpyridinium, methylquinolinium or dimethylimidazolium group and the other one is a phenyl ring para-substituted by a pyrimidine ring) have been investigated in buffered (pH = 7) aqueous solution. As found in previous works for several analogues, these quaternized salts undergo efficient trans→cis photoisomerization while the yield of the radiative deactivation is very small at room temperature. The solvent effect on the spectral behaviour indicates the occurrence of intramolecular charge transfer which can induce interesting non-linear optical properties. The results of a study of the interactions of these salts with DNA, which might affect the cell metabolism, showed a relatively modest binding affinity for the pyridinium and imidazolium salts and a more substantial affinity for the quinolinium analogue. The formation of ligand-DNA complexes affects only slightly the radiative relaxation yield while leading to a relevant reduction of the isomerization yield. Measurements of the linear dichroism behaviour of the three compounds and comparison with three analogues bearing furan or thienyl groups, which have been found to display different affinity with DNA in previous works, gave interesting information on the nature of the ligand-DNA binding of these compounds. 相似文献
104.
It is well known that sea urchin embryos are able to activate different defense strategies against stress. We previously demonstrated that cadmium treatment triggers the accumulation of metal in embryonic cells and the activation of defense systems depending on concentration and exposure time, through the synthesis of heat shock proteins and/or the initiation of apoptosis. Here we show that Paracentrotus lividus embryos exposed to Cd adopt autophagy as an additional stratagem to safeguard the developmental program. At present, there are no data focusing on the role of this process in embryo development of marine organisms. 相似文献
105.
In the course of recent efforts to identify new potential antiproliferative active principles, Salvia leriifolia extracts and isolated constituents were evaluated for their cytotoxic activity against a panel of human cancer cell lines, including renal adenocarcinoma (ACHN), amelanotic melanoma (C32), colorectal adenocarcinoma (Caco‐2), lung large cell carcinoma (COR‐L23), malignant melanoma (A375), lung carcinoma (A549), and hepatocellular carcinoma (Huh‐7D12) cells. The hexane and CH2Cl2 extracts showed the strongest cytotoxic activity against the C32 cell line with IC50 values of 11.2 and 13.6 μg/ml, respectively, and the AcOEt extract was the most active extract against the COR‐L23 cell line (IC50 of 20.9 μg/ml). Buchariol, a sesquiterpene obtained by biofractionation of the CH2Cl2 extract, exhibited a higher activity than the positive control vinblastine against the C32 and A549 cell lines (IC50 values of 2.1 and 12.6 μM , resp.). Interesting results were also obtained for naringenin, a flavonoid isolated from the AcOEt extract, which exhibited a strong cytotoxic activity against the C32, LNCaP, and COR‐L23 cell lines (IC50 values of 2.2, 7.7, and 33.4 μM , resp.), compared to vinblastine (IC50 values of 3.3, 32.2, 50.0 μM , resp.). None of the tested compounds affected the proliferation of skin fibroblasts (142BR), suggesting a selective activity against tumor cells. 相似文献
106.
Vegliante MC Royo C Palomero J Salaverria I Balint B Martín-Guerrero I Agirre X Lujambio A Richter J Xargay-Torrent S Bea S Hernandez L Enjuanes A Calasanz MJ Rosenwald A Ott G Roman-Gomez J Prosper F Esteller M Jares P Siebert R Campo E Martín-Subero JI Amador V 《PloS one》2011,6(6):e21382
Recent studies have shown aberrant expression of SOX11 in various types of aggressive B-cell neoplasms. To elucidate the molecular mechanisms leading to such deregulation, we performed a comprehensive SOX11 gene expression and epigenetic study in stem cells, normal hematopoietic cells and different lymphoid neoplasms. We observed that SOX11 expression is associated with unmethylated DNA and presence of activating histone marks (H3K9/14Ac and H3K4me3) in embryonic stem cells and some aggressive B-cell neoplasms. In contrast, adult stem cells, normal hematopoietic cells and other lymphoid neoplasms do not express SOX11. Such repression was associated with silencing histone marks H3K9me2 and H3K27me3. The SOX11 promoter of non-malignant cells was consistently unmethylated whereas lymphoid neoplasms with silenced SOX11 tended to acquire DNA hypermethylation. SOX11 silencing in cell lines was reversed by the histone deacetylase inhibitor SAHA but not by the DNA methyltransferase inhibitor AZA. These data indicate that, although DNA hypermethylation of SOX11 is frequent in lymphoid neoplasms, it seems to be functionally inert, as SOX11 is already silenced in the hematopoietic system. In contrast, the pathogenic role of SOX11 is associated with its de novo expression in some aggressive lymphoid malignancies, which is mediated by a shift from inactivating to activating histone modifications. 相似文献
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A new iridoid glucoside has been isolated from Stachytarpheta mutabilis and assigned the structure and configuration of 6β-hydroxyipolamiide on the basis of 1H NMR and 13C NMR evidence. The conversion of this compound into penta- acetyllamiol proved the above assignment. 相似文献