Multiphoton microscopy, relying on the simultaneous absorption of two or more photons by a fluorophore, has come to occupy a prominent place in modern biomedical research with its ability to allow real-time observatio...Multiphoton microscopy, relying on the simultaneous absorption of two or more photons by a fluorophore, has come to occupy a prominent place in modern biomedical research with its ability to allow real-time observation of a single cell and molecules in intact tissues. Multiphoton microscopy exhibits nonlinear optical contrast properties, which can make it possible to provide an exceptionally large depth penetration with less phototoxicity. This system becomes more and more an inspiring tool for a non-invasive imaging system to realize "optical biopsy" and to examine the functions of living cells. In this review, we briefly present the physical principles and properties of multiphoton microscopy as well as the current applications in biological fields. In addition, we address what we see as the future potential of multiphoton microscopy for gastroenterologic research.展开更多
A method for real time observation of photo-cleavage of stretched λDNA at single molecular level by a fluorescent microscope coupled with CCD is developed. DNA molecules stained with YOYO-1 are stretched by the mo-le...A method for real time observation of photo-cleavage of stretched λDNA at single molecular level by a fluorescent microscope coupled with CCD is developed. DNA molecules stained with YOYO-1 are stretched by the mo-lecular combing technique and fixed on a modified slide. Then the process of photocleavage and relaxation of DNA under radiation of blue light is observed. We speculate that the conformation change of stretched DNA and the effect of water are likely to facilitate the effect of YOYO photocleav-age DNA molecules. The photocleavage effect of YOYO for stretched DNA may be useful to study DNA elasticity, cancer research as well as the interaction between DNA and dyes.展开更多
文摘Multiphoton microscopy, relying on the simultaneous absorption of two or more photons by a fluorophore, has come to occupy a prominent place in modern biomedical research with its ability to allow real-time observation of a single cell and molecules in intact tissues. Multiphoton microscopy exhibits nonlinear optical contrast properties, which can make it possible to provide an exceptionally large depth penetration with less phototoxicity. This system becomes more and more an inspiring tool for a non-invasive imaging system to realize "optical biopsy" and to examine the functions of living cells. In this review, we briefly present the physical principles and properties of multiphoton microscopy as well as the current applications in biological fields. In addition, we address what we see as the future potential of multiphoton microscopy for gastroenterologic research.
基金supposed by the National Natural Science Foundation of China(Grant No.19890385)the fund from the Chinese Academy of Sciences(Grant Nos.STZ-00-07,KJCX-06 and KSCXI-06)the Science and Technology Commission of Shanghai(Grant No.00XD1444029).
文摘A method for real time observation of photo-cleavage of stretched λDNA at single molecular level by a fluorescent microscope coupled with CCD is developed. DNA molecules stained with YOYO-1 are stretched by the mo-lecular combing technique and fixed on a modified slide. Then the process of photocleavage and relaxation of DNA under radiation of blue light is observed. We speculate that the conformation change of stretched DNA and the effect of water are likely to facilitate the effect of YOYO photocleav-age DNA molecules. The photocleavage effect of YOYO for stretched DNA may be useful to study DNA elasticity, cancer research as well as the interaction between DNA and dyes.