Search results for "toxicité"
showing 10 items of 21 documents
Valorization of natural drug products : from extraction to encapsulation
2020
This thesis was carried out at the Laboratory of Pharmacognosy and the Laboratory of Pharmaceutical technology, at the UFR Sciences de Santé, circonscription Pharmacy, in the University of Burgundy Franche-Comté, to find new natural molecules to encapsulate. First of all, we focused on the natural saponins from plants of the Vietnam biodiversity and the french horticulture, belonging to the three genera Dracaena, Cordyline (Asparagaceae) and Weigela (Caprifoliaceae). The work led to the successful isolation and elucidation of 42 natural saponins using various chromatographic techniques. The structures were determined by ESI mass spectrometry and NMR spectroscopy. Among the 17 pure compounds…
Chemical and biological study of saponins isolated from three malagasy species belonging to Caryophyllaceae, Pittosporaceae and Solanaceae families
2013
This thesis was carried out in the Laboratory of Pharmacognosy, in the Pharmacy section of the University of Burgundy. The principal theme of this laboratory is the research of natural compounds from tropical biodiversity, mainly saponins. In this context, the study of Malagasy plants, Polycarpaea corymbosa Lamk. (CARYOPHYLLACEAE), Pittosporum verticillatum Bojer subsp. verticillatum (PITTOSPORACEAE), Solanum incanum L. and S. heteracanthum Dunal. (SOLANACEAE) led to the isolation of fifteen natural glycosides by column chromatography, medium pressure liquid chromatography, flash chromatography, and vacuum liquid chromatography. The structures were elucidated mainly by the use of spectrosco…
Fluorescent organometallic complexes : when the photovoltaic leads to theranostics
2013
The goal of my PhD thesis was to synthesize new molecules, which give access to fluorescentorganometallic complexes with interesting properties for photovoltaic and theranostic. In thisproject, several main points have been studied.The first part of this manuscript concerns the synthesis of new metallocene and metalloporphyrinsbasedorganometallic complexes to the design of solar cells. After a short introduction, wepresented the synthesis of titanium complexes and metalloporphyrins in the first chapter. Inparticular, we described the synthesis of model compounds and the difficulties encountered duringthe transition to porphyrin derivatives. However, in view of results obtained and opportuni…
Effet insecticide de Bacillus thuringiensis kurstaki et d’une toxine bactérienne, le Spinosad, à l’égard des blattes domestiques adultes (Blattella g…
2012
Les blattes sont très étudiées en raison de leur impact sur la santé humaine et animale, sur les cultures et l’habitat. Blattella germanica est une blatte domestique prédominante qui représente un vecteur potentiel des maladies. En raison de sa nuisance elle a fait l’objet de plusieurs études, en vue d’une lutte efficace. Ces dernières années, une nouvelle approche toxicologique est apparue, elle consiste à développer de nouveaux insecticides issus essentiellement des molécules biologiques telles que les plantes et les microorganismes comme les champignons et les bactéries. Dans cette étude on s’est intéressé aux effets induits par le Bacillus thuringiensiskurstaki sur les adultes de B. ger…
L’exposition par des mélanges de perturbateurs endocriniens à faibles doses modifie la différenciation adipocytaire – CIME project
2012
L’exposition par des mélanges de perturbateurs endocriniens à faibles doses modifie la différenciation adipocytaire – CIME project. Colloque PNR-PE
Cardiotoxicity of cancer therapy
2011
Despite the development of new anti-cancer drugs such as anti-tyrosine kinases or anti-angiogenic therapy, cancer mortality remains high. These new molecules associated with advances in cancer surgery, radiotherapy and chemotherapy have succeeded in improving life expectancy in these patients. It has also allowed a long-term evaluation of the cardiovascular impact of these therapies. Many chemotherapy drugs, such as anthracyclines, lead to impaired cardiac function. The pathophysiological mechanisms of this cardiac dysfunction are complex, intricate and remain partially unknown. To reduce this cardiotoxicity, different pathways concerning administration modalities, drug presentation and the…
Isolation and caracterisation of saponins from three plants of Araliaceae and Dracaenaceae families and evaluation of their cytotoxic activities on t…
2010
The interest of the substances from natural origin, potentially antitumor led us to interest in triterpenoid and steroidal saponins of plants from the African biodiversity belonging to the Araliaceae and Dracaenaceae families of plants. Indeed, of the former studies undertaken on some plants of these two families led to obtaining complex and original molecules having excellent cytotoxic, immuno-modulating, anti-inflammatory properties. Within sight of these results we undertook pharmaco-chemical investigations on Cussonia arborea (Araliaceae), Dracaena deisteliana, and Dracaena arborea (Dracaenaceae), medicinal plants usually used in african traditional pharmacopeia to treat various disease…
Microglia and α-synuclein implication in Parkinson's disease
2011
Age-related neurodegenerative disorders like Parkinson’s disease take an enormous toll on individuals and on society. Despite extensive efforts, Parkinson’s disease remains incurable and only very limited treatments exist. Indeed, Parkinson’s pathogenesis is still not clear and research on its molecular mechanisms is ongoing. In this study, we focused our interest on two abnormal events occurring in Parkinson’s patients, namely α-synuclein aggregation and microglial activation. We first investigated α-synuclein and its abnormal polymerisation. For this purpose, we developed novel methods, which allowed the in vitro production of different types of α-synuclein oligomers. Using highly sensiti…
Pourquoi faut-il se préoccuper de la toxicité des pesticides pour les microorganismes du sol ?
2017
EABIOmE INRA; Pourquoi faut-il se préoccuper de la toxicité des pesticides pour les microorganismes du sol ?
Dynamics and toxicity of proteins with a high homology of sequences: approach by molecular dynamics and ab-initio calculations
2008
The elucidation of the structure and the biological function of proteins is a major stake for its implications in the biomedical research as well as in biotechnologies. In addition, there is a glass or dynamical transition for the proteins which occurs at around 200K: it has been observed by Neutron Scattering, X-ray diffraction and Mossbauer spectroscopy for different proteins. Above the transition temperature, the biological function is activated as the protein may diffuse between conformational sub-states. The microscopic origin of this transition is still debated in spite of significant advances in recent years showing the significant role of hydration. By using all-atoms classical mole…