A voltammetric determination of possible organic pollutants such as diol and phenolic compounds in water was studied using ferroceneboronic acid（FBA） as a redox-active marker.A cyclic voltammogram of FBA exhibited a...A voltammetric determination of possible organic pollutants such as diol and phenolic compounds in water was studied using ferroceneboronic acid（FBA） as a redox-active marker.A cyclic voltammogram of FBA exhibited a pair of oxidation and reduction peaks at 230 and 170 mV at pH 7.0,respectively,while another pair of redox peaks was observed in the presence of diol or phenolic compounds tested.The results were rationalized based on the formation of boronate esters of FBA with the added compounds.The changes in the redox peak currents were dependent on the concentration of the additives,suggesting a usefulness of FBA in the electrochemical determination of these compounds in water.展开更多
The killing of tumor cells by ionizing radiation beams in cancer radiotherapy is currently based on a rather empirical understanding of the basic mechanisms and effectiveness of DNA damage by radiation.By contrast,the...The killing of tumor cells by ionizing radiation beams in cancer radiotherapy is currently based on a rather empirical understanding of the basic mechanisms and effectiveness of DNA damage by radiation.By contrast,the mechanical behaviour of DNA encompassing sequence sensitivity and elastic transitions to plastic responses is much better understood.A novel approach is proposed here based on a micromechanical Silicon Nanotweezers device.This instrument allows the detailed biomechanical characterization of a DNA bundle exposed to an ionizing radiation beam delivered here by a therapeutic linear particle accelerator(LINAC).The micromechanical device endures the harsh environment of radiation beams and still retains molecular-level detection accuracy.In this study,the first real-time observation of DNA damage by ionizing radiation is demonstrated.The DNA bundle degradation is detected by the micromechanical device as a reduction of the bundle stiffness,and a theoretical model provides an interpretation of the results.These first real-time observations pave the way for both fundamental and clinical studies of DNA degradation mechanisms under ionizing radiation for improved tumor treatment.展开更多
基金supported in part by a Grant-in-Aid (Asia-Africa Program) from Tohoku University
文摘A voltammetric determination of possible organic pollutants such as diol and phenolic compounds in water was studied using ferroceneboronic acid（FBA） as a redox-active marker.A cyclic voltammogram of FBA exhibited a pair of oxidation and reduction peaks at 230 and 170 mV at pH 7.0,respectively,while another pair of redox peaks was observed in the presence of diol or phenolic compounds tested.The results were rationalized based on the formation of boronate esters of FBA with the added compounds.The changes in the redox peak currents were dependent on the concentration of the additives,suggesting a usefulness of FBA in the electrochemical determination of these compounds in water.
基金G.P.received a Doctoral Scholarship from the Institut National du Cancer and additional financial support provided by CNRS.
文摘The killing of tumor cells by ionizing radiation beams in cancer radiotherapy is currently based on a rather empirical understanding of the basic mechanisms and effectiveness of DNA damage by radiation.By contrast,the mechanical behaviour of DNA encompassing sequence sensitivity and elastic transitions to plastic responses is much better understood.A novel approach is proposed here based on a micromechanical Silicon Nanotweezers device.This instrument allows the detailed biomechanical characterization of a DNA bundle exposed to an ionizing radiation beam delivered here by a therapeutic linear particle accelerator(LINAC).The micromechanical device endures the harsh environment of radiation beams and still retains molecular-level detection accuracy.In this study,the first real-time observation of DNA damage by ionizing radiation is demonstrated.The DNA bundle degradation is detected by the micromechanical device as a reduction of the bundle stiffness,and a theoretical model provides an interpretation of the results.These first real-time observations pave the way for both fundamental and clinical studies of DNA degradation mechanisms under ionizing radiation for improved tumor treatment.
