235 research outputs found
The ESF 10B programming 2005-2008. Associative employment micro-projects, integration and local development : positive result for the Franche-Comté
The CRESS Franche-Comté manages an original device, by delegation of the European social fund, to help and subsidize associative microprojects, in favour of the employment and for territorial development. A first programming allowed creating a set of local initiatives, thanks to the mobilization of small associations, with skills but inexperienced in professional actions. It results new activities in favour of the social and ecological innovation. An important element of this device is the constitution of a network for identifying and supporting original initiatives. The poster is a descriptive of the first programming.la CRESS Franche-Comté gère un dispositif original, par délégation du fond social européen, pour accompagner et subventionner des microprojets associatifs, en faveur de l'emploi, de l'insertion et du développement territorial. Une première programmation a permis de faire émerger un ensemble d'initiatives locales, grâce à la mobilisation de petites associations, avec des compétences en main, mais inexpérimentées dans l'action professionnelle. Il en résulte de nouvelles activités en faveur de l'innovation sociale et écologique. Un élément important de ce dispositif est la constitution d'un réseau qui a permis d'identifier et faire émerger les initiatives, les soutenir pour une bonne mise en oeuvre. Le poster est un bilan descriptif de la première programmation
Non profit-making home-care in the Franche-Comté : An example of structuring of a professional branch within the social and solidarity based economy.
International audienceThe sector of the home help knows a strong development for some years, in reason in particular of the ageing of the population. In Franche-Comté, associations created the first regional professional collective of France. It represents more than 4000 employees. The employment is there mainly feminine and part-time. The objective is to lead a coherent development policy with the principles of the social economy: satisfaction of the user, the quality of the employment. A first stage of professionalization and a consolidation of the employment was successfully led, thanks to an agreement of yearly adjustment of the working time bound to a strong training policy. The current stake concerns the financial consolidation, in front of a low-cost competition which has no same quality objectives. It is a question of mobilizing the beneficiaries of the service as " consom' actors ".La filière de l'aide à domicile connaît un fort développement depuis quelques années, en raison notamment du vieillissement de la population. En Franche-Comté, les associations ont créé le premier collectif professionnel régional de France. Il représente plus de 4000 salariés. L'emploi y est principalement féminin et à temps partiel. L'objectif est de mener une politique de développement cohérente avec les principes de l'économie sociale : satisfaction de l'usager, qualité de l'emploi. Une première étape de professionnalisation et consolidation de l'emploi a été menée avec succès, grâce à l'annualisation du temps de travail liée à une politique de formation forte. L'enjeu actuel concerne la consolidation financière, face à une concurrence à faible coût qui n'a pas les mêmes objectifs de qualité. Il s'agit de mobiliser les bénéficiaires du service comme " consom'acteurs "
A social barometer
International audienceThe new deal in local development and employment public policies lead more and more to a territorial organization. USGERES wishes to endow the employers of the social economy with a new method for a labormanagement dialog, answering the objectives of satisfaction of the beneficiaries of the activity, but also the individual development of the employees. A process, called social barometer, was experimented. It is based on qualitative and quantitative inquiries, analyzed by a steering committee. It allows building new actions for the quality of the employment and the development of activity, and also introduces a new dynamics of professional and local animation
A fragment merging approach towards the development of small molecule inhibitors of Mycobacterium tuberculosis EthR for use as ethionamide boosters.
With the ever-increasing instances of resistance to frontline TB drugs there is the need to develop novel strategies to fight the worldwide TB epidemic. Boosting the effect of the existing second-line antibiotic ethionamide by inhibiting the mycobacterial transcriptional repressor protein EthR is an attractive therapeutic strategy. Herein we report the use of a fragment based drug discovery approach for the structure-guided systematic merging of two fragment molecules, each binding twice to the hydrophobic cavity of EthR from M. tuberculosis. These together fill the entire binding pocket of EthR. We elaborated these fragment hits and developed small molecule inhibitors which have a 100-fold improvement of potency in vitro over the initial fragments.We also thank the Bill and Melinda Gates Foundation and the EU FP7 MM4TB Grant n°260872, the ERC-STG INTRACELLTB Grant n°260901, the Agence Nationale de la Recherche (ANR-10-EQPX-04-01), the Feder (12001407 (D-AL) Equipex Imaginex BioMed) and the Région Nord Pas de Calais, France, for providing funding to support this work.This is the final version of the article. It first appeared from the Royal Society of Chemistry via http://dx.doi.org/10.1039/C5OB02630
Unconventional surface plasmon resonance signals reveal quantitative inhibition of transcriptional repressor EthR by synthetic ligands
International audienceEthR is a mycobacterial repressor that limits the bioactivation of ethionamide, a commonly used anti-tuberculosis second-line drug. Several efforts have been deployed to identify EthR inhibitors abolishing the DNA-binding activity of the repressor. This led to the demonstration that stimulating the bioactivation of ETH through EthR inhibition could be an alternative way to fight Mycobacterium tuberculosis. We propose a new SPR methodology to study the affinity between inhibitors and EthR. Interestingly, the binding between inhibitors and immobilized EthR produced a dose dependent negative SPR signal. We demonstrated that this signal reveals the affinity of the small molecules for the repressor. The affinity constants (KD) correlated with their capacity to inhibit the binding of EthR to DNA. We hypothesize that conformational changes of EthR during ligand interaction could be responsible for this SPR signal. Practically, this unconventional result open perspectives to the development of SPR assay that would at the same time tough on the structural changes of the target upon binding with an inhibitor and on the binding constant of this interaction
Complete structure of the chemosensory array core signalling unit in an E. coli 1 minicell strain
Motile bacteria sense chemical gradients with transmembrane receptors organised in supramolecular signalling arrays. Understanding stimulus detection and transmission at the molecular level requires precise structural characterisation of the array building block known as a core signalling unit. Here we introduce an Escherichia coli strain that forms small minicells possessing extended and highly ordered chemosensory arrays. We use cryo-electron tomography and subtomogram averaging to provide a three-dimensional map of a complete core signalling unit, with visible densities corresponding to the HAMP and periplasmic domains. This map, combined with previously determined high resolution structures and molecular dynamics simulations, yields a molecular model of the transmembrane core signalling unit and enables spatial localisation of its individual domains. Our work thus offers a solid structural basis for the interpretation of a wide range of existing data and the design of further experiments to elucidate signalling mechanisms within the core signalling unit and larger array
Synthesis, antitubercular activity and mechanism of resistance of highly effective thiacetazone analogues
Defining the pharmacological target(s) of currently used drugs and developing new analogues with greater potency are both important aspects of the search for agents that are effective against drug-sensitive and drug-resistant Mycobacterium tuberculosis. Thiacetazone (TAC) is an anti-tubercular drug that was formerly used in conjunction with isoniazid, but removed from the antitubercular chemotherapeutic arsenal due to toxic side effects. However, several recent studies have linked the mechanisms of action of TAC to mycolic acid metabolism and TAC-derived analogues have shown increased potency against M. tuberculosis. To obtain new insights into the molecular mechanisms of TAC resistance, we isolated and analyzed 10 mutants of M. tuberculosis that were highly resistant to TAC. One strain was found to be mutated in the methyltransferase MmaA4 at Gly101, consistent with its lack of oxygenated mycolic acids. All remaining strains harbored missense mutations in either HadA (at Cys61) or HadC (at Val85, Lys157 or Thr123), which are components of the bhydroxyacyl-ACP dehydratase complex that participates in the mycolic acid elongation step. Separately, a library of 31 new TAC analogues was synthesized and evaluated against M. tuberculosis. Two of these compounds, 15 and 16, exhibited minimal inhibitory concentrations 10-fold lower than the parental molecule, and inhibited mycolic acid biosynthesis in a dose-dependent manner. Moreover, overexpression of HadAB HadBC or HadABC in M. tuberculosis led to high level resistance to these compounds, demonstrating that their mode of action is similar to that of TAC. In summary, this study uncovered new mutations associated with TAC resistance and also demonstrated that simple structural optimization of the TAC scaffold was possible and may lead to a new generation of TAC-derived drug candidates for the potential treatment of tuberculosis as mycolic acid inhibitors
Structural activation of the transcriptional repressor EthR from Mycobacterium tuberculosis by single amino acid change mimicking natural and synthetic ligands
Ethionamide is an antituberculous drug for the treatment of multidrug-resistant Mycobacterium tuberculosis. This antibiotic requires activation by the monooxygenase EthA to exert its activity. Production of EthA is controlled by the transcriptional repressor EthR, a member of the TetR family. The sensitivity of M. tuberculosis to ethionamide can be artificially enhanced using synthetic ligands of EthR that allosterically inactivate its DNA-binding activity. Comparison of several structures of EthR co-crystallized with various ligands suggested that the structural reorganization of EthR resulting in its inactivation is controlled by a limited portion of the ligand-binding-pocket. In silico simulation predicted that mutation G106W may mimic ligands. X-ray crystallography of variant G106W indeed revealed a protein structurally similar to ligand-bound EthR. Surface plasmon resonance experiments established that this variant is unable to bind DNA, while thermal shift studies demonstrated that mutation G106W stabilizes EthR as strongly as ligands. Proton NMR of the methyl regions showed a lesser contribution of exchange broadening upon ligand binding, and the same quenched dynamics was observed in apo-variant G106W. Altogether, we here show that the area surrounding Gly106 constitutes the molecular switch involved in the conformational reorganization of EthR. These results also shed light on the mechanistic of ligand-induced allosterism controlling the DNA binding properties of TetR family repressors
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Fragment-Sized EthR Inhibitors Exhibit Exceptionally Strong Ethionamide Boosting Effect in Whole-Cell Assays
Small-molecule inhibitors of the mycobacterial transcriptional repressor EthR have previously been shown to act as boosters of the second-line antituberculosis drug ethionamide. Fragment-based drug discovery approaches have been used in the past to make highly potent EthR inhibitors with ethionamide boosting activity both and . Herein, we report the development of fragment-sized EthR ligands with nanomolar minimum effective concentration values for boosting the ethionamide activity in whole-cell assays.We would like to thank A. Coyne for help in the preparation of this manuscript. P.O.N. would like to thank the EPSRC for providing Ph.D. funding. We also thank the Bill and Melinda Gates Foundation and the EU FP7MM4TB Grant No. 260872, the ERC-STG INTRACELLTB Grant No. 260901, the Agence Nationale de la Recherche (ANR-10-EQPX-04-01), the Feder (12001407 (D-AL) Equipex Imaginex BioMed), the Intramural Research Program of the National Institutes of Health/NIAID, and the Région Nord Pas de Calais, France, for providing funding to support this work
Intrinsic antibacterial activity of nanoparticles made of β-cyclodextrins potentiates their effect as drug nanocarriers against tuberculosis
Multi-drug-resistant tuberculosis (TB) is a major public health problem, concerning about half a million cases each year. Patients hardly adhere to the current strict treatment consisting of more than 10 000 tablets over a 2-year period. There is a clear need for efficient and better formulated medications. We have previously shown that nanoparticles made of cross-linked poly-β-cyclodextrins (pβCD) are efficient vehicles for pulmonary delivery of powerful combinations of anti-TB drugs. Here, we report that in addition to being efficient drug carriers, pβCD nanoparticles are endowed with intrinsic antibacterial properties. Empty pβCD nanoparticles are able to impair Mycobacterium tuberculosis (Mtb) establishment after pulmonary administration in mice. pβCD hamper colonization of macrophages by Mtb by interfering with lipid rafts, without inducing toxicity. Moreover, pβCD provoke macrophage apoptosis, leading to depletion of infected cells, thus creating a lung microenvironment detrimental to Mtb persistence. Taken together, our results suggest that pβCD nanoparticles loaded or not with antibiotics have an antibacterial action on their own and could be used as a carrier in drug regimen formulations effective against TB.SCOPUS: ar.jinfo:eu-repo/semantics/publishe
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