In this work, we have considered a new multimodality imaging for macroscopy based on Second Harmonic Generation (SHG) method to monitor invasivelessly the matrix collagen. As the triple helicoidally structure of colla...In this work, we have considered a new multimodality imaging for macroscopy based on Second Harmonic Generation (SHG) method to monitor invasivelessly the matrix collagen. As the triple helicoidally structure of collagen molecules appearing as not centrosymetric, very organized and spatially oriented, collagen fibrils give rise to a very strong SHG signal and can be imaged without any exogenous dye. To integrate a multidimensional scale with a large field of view (non-sliced samples), we have adapted and validated an instrumental coupling between a two photon excitation laser and a macroscope to collect cartography of SHG signal. We introduced an index (F-SHG) based on decay time response measured by TCSPC for respectively Fluorescence (F) and Second Harmonic Generation (SHG) values. For various sample where protein collagen is the major component of extracellular matrix (vessel, skin, carotide vessel, rat femoral head cartilage, mouse tumor, human wharton’s jelly and rat tendon) or not (nacre), we compared the index distribution obtained with MacroSHG. In this work, we showed for the first time that multiscale large field imaging (Macroscopy) combined to Multimodality approaches (SHG-TCSPC) could be an innovative and non-invasive technique to detect and identify some biological interest molecules (collagen) in biomedical topics.展开更多
1 Introduction Obstructive atherosclerosis vascular disease remains one of the greatest public health threats in the world.Sur2 gical treatment to replace diseased blood vessels is usually done using major human allog...1 Introduction Obstructive atherosclerosis vascular disease remains one of the greatest public health threats in the world.Sur2 gical treatment to replace diseased blood vessels is usually done using major human allografts(veins or arteries)or synthetic prosthesis(PTFE,Dacron).However,these substitutes have not a good patency,because of the lack of endothelial cell s(ECs)layer,which prevent s thrombus formation.The challenge of tissue engineering vessel s i s to build2up blood/substitute interface near native vessels.In order to improve ECs adhesion,it is necessary to pre2 coat the intra2luminal vessel.Recently,a new surface modification technique arose,based on the alternate ad2 sorption of oppositely charged polyelectrolytes.Our objec2 tive was to favour the endothelialization of the cryo2pre2 served allografts,treated with a thin polyelectrolyte multi2 layered film,made of PSS(poly(sodium242styrenesul2 fonate))or PAH(poly(allylamine hydrochloride)).展开更多
文摘In this work, we have considered a new multimodality imaging for macroscopy based on Second Harmonic Generation (SHG) method to monitor invasivelessly the matrix collagen. As the triple helicoidally structure of collagen molecules appearing as not centrosymetric, very organized and spatially oriented, collagen fibrils give rise to a very strong SHG signal and can be imaged without any exogenous dye. To integrate a multidimensional scale with a large field of view (non-sliced samples), we have adapted and validated an instrumental coupling between a two photon excitation laser and a macroscope to collect cartography of SHG signal. We introduced an index (F-SHG) based on decay time response measured by TCSPC for respectively Fluorescence (F) and Second Harmonic Generation (SHG) values. For various sample where protein collagen is the major component of extracellular matrix (vessel, skin, carotide vessel, rat femoral head cartilage, mouse tumor, human wharton’s jelly and rat tendon) or not (nacre), we compared the index distribution obtained with MacroSHG. In this work, we showed for the first time that multiscale large field imaging (Macroscopy) combined to Multimodality approaches (SHG-TCSPC) could be an innovative and non-invasive technique to detect and identify some biological interest molecules (collagen) in biomedical topics.
文摘1 Introduction Obstructive atherosclerosis vascular disease remains one of the greatest public health threats in the world.Sur2 gical treatment to replace diseased blood vessels is usually done using major human allografts(veins or arteries)or synthetic prosthesis(PTFE,Dacron).However,these substitutes have not a good patency,because of the lack of endothelial cell s(ECs)layer,which prevent s thrombus formation.The challenge of tissue engineering vessel s i s to build2up blood/substitute interface near native vessels.In order to improve ECs adhesion,it is necessary to pre2 coat the intra2luminal vessel.Recently,a new surface modification technique arose,based on the alternate ad2 sorption of oppositely charged polyelectrolytes.Our objec2 tive was to favour the endothelialization of the cryo2pre2 served allografts,treated with a thin polyelectrolyte multi2 layered film,made of PSS(poly(sodium242styrenesul2 fonate))or PAH(poly(allylamine hydrochloride)).
