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151.
152.
Angela Theodorou Mavroudis A. Demertzis Dimitra Kovala-Demertzi Efthimia E. Lioliou Anastasia A. Pantazaki Dimitrios A. Kyriakidis 《Biometals》1999,12(2):167-172
Copper(II) complexes of diclofenac with interesting anti-inflammatory profiles have been prepared and studied by infrared and electronic spectroscopy. In the solid state and in polar and coordinating solvents, all the complexes are solvated binuclear carboxylato-bridged complexes, [Cu(L)2(S)]2, where L is monodeprotonated diclofenac and S is the axially bonded solvent. The effect of the copper(II) complexes on the in vitro DNA strand breakeage was studied by agarose gel electrophoresis. Relaxation or double stranded scissions of pDNA were observed leading to the formation of linear pDNA. Treatment of pDNA with high concentrations of these compounds caused a disappearance of pDNA. For the parent drug, sodium diclofenac, no effect on the pDNA was observed. This study presents some indications that the binuclear copper(II) complexes, [Cu(L)2(S)]2, could have some relevance in the treatment of tumor cell lines. 相似文献
153.
Anastasia Detsi Maya Majdalani Christos A. Kontogiorgis Dimitra Hadjipavlou-Litina Panagiotis Kefalas 《Bioorganic & medicinal chemistry》2009,17(23):8073-8085
A series of 2′-hydroxy-chalcones and their oxidative cyclization products, aurones, have been synthesized and tested for their antioxidant and lipoxygenase inhibitory activity. The natural product aureusidin (31) was synthesized in high yield by a new approach. An extensive structure-relationship study was performed and revealed that several chalcones and aurones possess an appealing pharmacological profile combining high antioxidant and lipid peroxidation activity with potent soybean LOX inhibition. 相似文献
154.
The novel triphenyltin(IV) esters of flufenamic acid (1), Hflu, [Ph3Sn(flu)] (2), and of [2-(2,3-dichlorophenylamino)benzoic acid] (3), Hdcpa, [Ph3Sn(dcpa)] (4) have been structurally characterized by means of vibrational and 1H, 13C NMR spectroscopic studies. The crystal and molecular structures of [SnPh3(dcpa)(DMSO)] 4a are described. The molecular structure of 4a reveals that the Sn atom has a distorted trigonal bipyramidal coordination geometry with equatorial phenyl groups and the carboxylate and dimethylsulfoxide oxygen atoms occupying axial positions. The crystal structure of 4a is self-assembled by C-H---π and π-π stacking interactions. The in vitro cytotoxic activity of 1-4 and of the related non-steroidal anti-inflammatory drugs, NSAIDs, [2-(2,6-dimethylphenylamino)benzoic acid], Hdmpa (5), [Ph3Sn(dmpa)] (6), [2-(2,3-dimethylphenylamino)benzoic acid], mefenamic acid, Hmef (7) and [Ph3Sn(mef)] (8) has been evaluated against the cancer cell lines MCF-7, T-24, A-549 and L-929. The ligands exhibited very poor cytotoxic activity against the four cancer cell lines. Complex 6 exhibits the highest activity and selectivity against A-549 and MCF-7 cancer cell lines and complex 8 the highest activity and selectivity against T-24 cancer cell line. The cytotoxic results indicate that coupling of Hdmpa and Hmef with R3Sn(IV) metal center results in complexes with important biological properties and remarkable cytotoxic activity, since they display IC50 values in a μΜ range better to that of the antitumor drug cis-platin. Complexes 6 and 8 are considered as excellent antitumor compounds and the results of this study represent the discovery of triphenyltin(IV)esters as a potential novel class of anticancer agents. 相似文献
155.
Gabriela Petrof Arti Nanda Jake Howden Takuya Takeichi James R. McMillan Sophia Aristodemou Linda Ozoemena Lu Liu Andrew P. South Celine Pourreyron Dimitra Dafou Laura E. Proudfoot Hejab Al-Ajmi Masashi Akiyama W.H. Irwin McLean Michael A. Simpson Maddy Parsons John A. McGrath 《American journal of human genetics》2014
156.
Lina Liljenfeldt Katerina Gkirtzimanaki Dimitra Vyrla Emma Svensson Angelica SI Loskog Aristides G. Eliopoulos 《Cancer immunology, immunotherapy : CII》2014,63(3):273-282
Bystander immune activation by chemotherapy has recently gained extensive interest and provided support for the clinical use of chemotherapeutic agents in combination with immune enhancers. The CD40 ligand (CD40L; CD154) is a potent regulator of the anti-tumor immune response and recombinant adenovirus (RAd)-mediated CD40L gene therapy has been effective in various cancer models and in man. In this study we have assessed the combined effect of local RAd-CD40L and 5-fluorouracil (5-FU) administration on a syngeneic MB49 mouse bladder tumor model. Whereas MB49 cells implanted into immunocompetent mice responded poorly to RAd-CD40L or 5-FU alone, administration of both agents dramatically decreased tumor growth, increased survival of the mice and induced systemic MB49-specific immunity. This combination treatment was ineffective in athymic nude mice, highlighting an important role for T cell mediated anti-tumor immunity for full efficacy. 5-FU up-regulated the expression of Fas and immunogenic cell death markers in MB49 cells and cytotoxic T lymphocytes from mice receiving RAd-CD40L immunotherapy efficiently lysed 5-FU treated MB49 cells in a Fas ligand-dependent manner. Furthermore, local RAd-CD40L and 5-FU administration induced a shift of myeloid-derived suppressor cell phenotype into a less suppressive population. Collectively, these data suggest that RAd-CD40L gene therapy is a promising adjuvant treatment to 5-FU for the management of bladder cancer. 相似文献
157.
Atomic‐Layer‐Deposited Aluminum and Zirconium Oxides for Surface Passivation of TiO2 in High‐Efficiency Organic Photovoltaics 下载免费PDF全文
Maria Vasilopoulou Dimitra G. Georgiadou Anastasia Soultati Nikos Boukos Spyros Gardelis Leonidas C. Palilis Mihalis Fakis Georgios Skoulatakis Stella Kennou Martha Botzakaki Stavroula Georga Christoforos A. Krontiras Florian Auras Dina Fattakhova‐Rohlfing Thomas Bein Theodoros A. Papadopoulos Dimitrios Davazoglou Panagiotis Argitis 《Liver Transplantation》2014,4(15)
The reduction in electronic recombination losses by the passivation of surfaces is a key factor enabling high‐efficiency solar cells. Here a strategy to passivate surface trap states of TiO2 films used as cathode interlayers in organic photovoltaics (OPVs) through applying alumina (Al2O3) or zirconia (ZrO2) insulating nanolayers by thermal atomic layer deposition (ALD) is investigated. The results suggest that the surface traps in TiO2 are oxygen vacancies, which cause undesirable recombination and high electron extraction barrier, reducing the open‐circuit voltage and the short‐circuit current of the complete OPV device. It is found that the ALD metal oxides enable excellent passivation of the TiO2 surface followed by a downward shift of the conduction band minimum. OPV devices based on different photoactive layers and using the passivated TiO2 electron extraction layers exhibit a significant enhancement of more than 30% in their power conversion efficiencies compared to their reference devices without the insulating metal oxide nanolayers. This is a result of significant suppression of charge recombination and enhanced electron extraction rates at the TiO2/ALD metal oxide/organic interface. 相似文献
158.
Dialynas GK Makatsori D Kourmouli N Theodoropoulos PA McLean K Terjung S Singh PB Georgatos SD 《The Journal of biological chemistry》2006,281(20):14350-14360
We have examined HP1beta-chromatin interactions in different molecular contexts in vitro and in vivo. Employing purified components we show that HP1beta exhibits selective, stoichiometric, and salt-resistant binding to recombinant histone H3, associating primarily with the helical "histone fold" domain. Furthermore, using "bulk" nucleosomes released by MNase digestion, S-phase extracts, and fragments of peripheral heterochromatin, we demonstrate that HP1beta associates more tightly with destabilized or disrupted nucleosomes (H3/H4 subcomplexes) than with intact particles. Western blotting and mass spectrometry data indicate that HP1beta-selected H3/H4 particles and subparticles possess a complex pattern of posttranslational modifications but are not particularly enriched in me3K9-H3. Consistent with these results, mapping of HP1beta and me3K9-H3 sites in vivo reveals overlapping, yet spatially distinct patterns, while transient transfection assays with synchronized cells show that stable incorporation of HP1beta-gfp into heterochromatin requires passage through the S-phase. The data amassed challenge the dogma that me3K9H3 is necessary and sufficient for HP1 binding and unveil a new mode of HP1-chromatin interactions. 相似文献
159.
160.
Georgios Grammatikos Christiane Mühle Nerea Ferreiros Sirkka Schroeter Dimitra Bogdanou Stephanie Schwalm Gudrun Hintereder Johannes Kornhuber Stefan Zeuzem Christoph Sarrazin Josef Pfeilschifter 《Biochimica et Biophysica Acta (BBA)/Molecular and Cell Biology of Lipids》2014,1841(7):1012-1020
Sphingolipids constitute bioactive molecules with functional implications in homeostasis and pathogenesis of various diseases. However, the role of sphingolipids as possible disease biomarkers in chronic liver disease remains largely unexplored. In the present study we used mass spectrometry and spectrofluorometry methods in order to quantify various sphingolipid metabolites and also assess the activity of an important corresponding regulating enzyme in the serum of 72 healthy volunteers as compared to 69 patients with non-alcoholic fatty liver disease and 69 patients with chronic hepatitis C virus infection. Our results reveal a significant upregulation of acid sphingomyelinase in the serum of patients with chronic liver disease as compared to healthy individuals (p < 0.001). Especially in chronic hepatitis C infection acid sphingomyelinase activity correlated significantly with markers of hepatic injury (r = 0.312, p = 0.009) and showed a high discriminative power. Accumulation of various (dihydro-) ceramide species was identified in the serum of patients with non-alcoholic fatty liver disease (p < 0.001) and correlated significantly to cholesterol (r = 0.448, p < 0.001) but showed a significant accumulation in patients with normal cholesterol values as well (p < 0.001). Sphingosine, a further bioactive metabolite, was also upregulated in chronic liver disease (p < 0.001). However, no significant correlation to markers of hepatic injury was identified. Conclusion: Chronic hepatitis C virus infection and non-alcoholic fatty liver disease induce a significant upregulation of serum acid sphingomyelinase which appears as a novel biomarker in chronic hepatopathies. Further studies are required to elucidate the potential of the sphingolipid signaling pathway as putative therapeutic target in chronic liver disease. 相似文献