40 research outputs found
Premature removal of condoms by young men in Abidjan, CĂŽte d'Ivoire : an example of an AIDS prevention
Quilamine HQ1-44, an iron chelator vectorized toward tumor cells by the polyamine transport system, inhibits HCT116 tumor growth without adverse effect
International audienceTumor cell growth requires large iron quantities and the deprivation of this metal induced by synthetic metal chelators is therefore an attractive method for limiting the cancer cell proliferation. The antiproliferative effect of the Quilamine HQ1-44, a new iron chelator vectorized toward tumor cells by a polyamine chain, is related to its high selectivity for the Polyamine Transport System (PTS), allowing its preferential uptake by tumoral cells. The difference in PTS activation between healthy cells and tumor cells enables tumor cells to be targeted, whereas the strong dependence of these cells on iron ensures a secondary targeting. Here, we demonstrated in vitro that HQ1-44 inhibits DNA synthesis and cell proliferation of HCT116 cells by modulating the intracellular metabolism of both iron and polyamines. Moreover, in vivo, in xenografted athymic nude mice, we found that HQ1-44 was as effective as cis-platin in reducing HCT116 tumor growth, without its side effects. Furthermore, as suggested by in vitro data, the depletion in exogenous or endogenous polyamines, known to activate the PTS, dramatically enhanced the antitumor efficiency of HQ1-44. These data support the need for further studies to assess the value of HQ1-44 as an adjuvant treatment in cance
Recent advances in cancer treatment by Iron Chelators
International audienceThe development of new therapeutic alternatives for cancers is a major public health priority. Among the more promising approaches, the iron depletion strategy based on metal chelation in the tumoral environment has been particularly studied in recent decades. After a short description of the importance of iron for cancer cell proliferation, we will review the different iron chelators developed as potential chemotherapeutics. Finally, the recent efforts to vectorize the chelating agents specifically in the microtumoral environment will be discussed in detai
LâingĂ©nierie systĂšme au service de la conception dâun parcours de formation
National audienceUn eÌtablissement de formation peut eÌtre consideÌreÌ comme un systeÌme de production de compeÌtences. Sur la base de cette hypotheÌse, lâingeÌnierie systeÌme permet de deÌfinir, de structurer et dâaider aÌ la conception de parcours de formation. Ainsi, en positionnant le parcours de formation dans la chaiÌne de valeur du systeÌme de production de compeÌtences, cet article preÌsente une reÌflexion sur lâapport de lâingeÌnierie systeÌme. Deux systeÌmes sont consideÌreÌs : le systeÌme pour faire (projet dâingeÌnierie du parcours de formation) et le systeÌme aÌ faire (parcours de formation). La conception du parcours demande la deÌfinition dâun reÌfeÌrentiel baseÌ sur le modeÌle constructiviste des sciences et de son interpreÌtation. Pour cela, cet article introduit le contexte de deÌfinition des compeÌtences requises pour le meÌtier dâingeÌnieur systeÌme. Le parcours de formation doit eÌtre consideÌreÌ comme un service rendu aux apprenants ainsi quâaux organismes demandeurs de compeÌtences meÌtier speÌcifiques. Cela conduit aÌ suggeÌrer de deÌvelopper cette reÌflexion sur la base des travaux en cours, notamment dans le comiteÌ technique de l'AFIS chargeÌ de la formation et des compeÌtences, ainsi que dans celui qui deÌveloppe une reÌflexion sur lâingeÌnierie des systeÌmes de production de service