8 research outputs found

    Titan Based Hybrid Organic-Inorganic Gels Comprising Carbohydrate Moiety

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    International audienceA series of titanium based gels comprising carbohydrate moieties was synthesized. The sugars used include a specific hydrazide group as complex forming agent. Additionally, this group forms stable hydrates which allow further slow water release. As a result, the compounds used in this study form transparent and stable gels with titanium alkoxide without addition of external water. Interpretation of the IR-spectra reveals that some compounds form monodentate ligands and other bidentate ligands. Further Tian-Calvet calorimetric measurements confirmed our IR-based conclusions. This strategy of synthesis gives a new opportunity to obtain hybrid materials by addition of natural chelating ligands to slow down the hydrolysis/condensation reactions that occur during the sol-gel process. Therefore, carbohydrate moieties have been incorporated in the gels obtained and different type of Ti coordination was proposed based on the IR spectroscopy studies. SEM investigations show the influence of the ligand on the morphology of the xerogel. GRAPHICAL ABSTRAC

    Evaluation of the potential of a new ribavirin analog impairing the dissemination of ovarian cancer cells

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    International audienceEpithelial ovarian cancers are insidious pathologies that give a poor prognosis due to their late discovery and the increasing emergence of chemoresistance. Development of small pharmacological anticancer molecules remains a major challenge. Ribavirin, usually used in the treatment of hepatitis C virus infections and more recently few cancers, has been a suggestion. However, Ribavirin has many side-effects, suggesting that the synthesis of analogs might be more appropriate. We have investigated the effect of a Ribavirin analog, SRO-91, on cancer cell behavioral characteristics considered as some of the hallmarks of cancer. Two human ovarian adenocarcinoma cell lines (SKOV3 and IGROV1) and normal cells (mesothelial and fibroblasts) have been used to compare the effects of SRO-91 with those of Ribavirin on cell behavior underlying tumor cell dissemination. SRO-91, like Ribavirin, inhibits proliferation, migration, clonogenicity and spheroids formation of cancer cells. Unlike Ribavirin, SRO-91 is preferentially toxic to cancer compared with normal cells. An in vitro physiologically relevant model showed that SRO-91, like Ribavirin or cisplatin, inhibits cancer cell implantation onto peritoneal mesothelium. In conclusion, SRO-91 analog effects on tumor dissemination and its safety regarding non-cancerous (normal) cells are encouraging findings a promising drug for the treatment of ovarian cancer

    Conservation and alteration of painting pigments: the case of green copper-based organometallic pigments

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    International audienceGreen copper organometallic pigments have been known since Antiquity. Some of them, such as verdigris and copper resinate, were widely used in easel paintings from the 15th to 17th centuries, for their transparency, brilliance and pure green tones.However these pigments often undergo chromatic modifications, like browning or darkening. This phenomenon is not systematic, and altered and non-altered areas can coexist in a same painting.The understanding of the darkening process is crucial for conservation issues, to improve the readability of degraded paintings and decide how to treat them
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