H Schneckenburger

..In addition, particularly with regard to potential pharmaceutical applications, the kinetics of the intracellular translocation of a fluorescent protein kinase c fusion protein upon stimulation of the cells is determined...

..In addition to conventional fluorescent dyes, genetically engineered fluorescent proteins are increasingly being used to measure molecular conformations or intermolecular distances by fluorescence resonance energy transfer...

..Therefore, for diagnostic applications the concentration of R123 in the incubation medium should not be above 25 microM...

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..High transfection rates, visual control and universality towards various cell lines are possibly the main advantages of laser-assisted optoporation in comparison with presently existing methods of cell transfection...

..Concomitantly the amount of mitochondrial NADH increased. Excellent linearity between the number of cells incubated with R123 and fluorescence intensity was found in suspension...

..Two-photon excitation of NAD(P)H and flavins may also affect cell viability after exposure to 670-680 nm, whereas one-photon excitation of water molecules seems to limit cell viability at 1064 nm...

..Therefore, time-gated energy transfer spectroscopy is suggested to be an appropriate tool for probing mitochondrial malfunction...

..We conclude that time-gated spectroscopy combined with non-radiative energy transfer is an appropriate tool for probing mitochondrial enzyme complex deficiencies...

..The compact illumination device is also suitable for combining TIRFM with further innovative techniques, e.g. time-resolved fluorescence spectroscopy, fluorescence lifetime imaging (FLIM) or fluorescence resonance energy transfer (FRET)...

..In conclusion, these results provide for the first time direct evidence for a plasma membrane-associated fraction of the hydrophilic compounds TPPS3 and TPPS4 in living cells...

..Tolerable light doses were also maintained in fluorescence microscopy of larger 3D samples, e.g. cell spheroids exposed to structured illumination, but may be exceeded in super-resolution microscopy based on single molecule detection...

..Non-radiative energy transfer was used to detect laurdan selectively in close proximity to a molecular acceptor (DiI) and may present a possibility for measuring membrane dynamics in specific microenvironments...

..Although present applications are still limited by their low pulse energy (< or = 5 pJ), uv picosecond laser diodes have a large potential in high resolution fluorescence microscopy and fluorescence lifetime endoscopy...

..Therefore, this test system appears to be a sensitive device for the detection of apoptosis and more generally for drug screening or in vitro diagnosis on a nanometer scale...

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..Spectral properties are evaluated and displayed as microscopic images...

..For all measurements in this study, either human glioblastoma cells incubated with the fluorescent membrane marker NBD-cholesterol or human breast cancer cells expressing a membrane-associating fluorescent protein were used...

..Moreover, focal contacts visualized with a fusion protein of yellow fluorescent protein and focal adhesion kinase were maintained on light exposure, i.e., light-induced detachment of cells from their substrate was not likely to occur...

..A combination of TIR and fluorescence lifetime imaging microscopy (FLIM), described for the first time, appears to be promising for understanding some key mechanisms of photodynamic therapy (PDT)...

..To analyze the impact of alterations in cholesterol level upon BACE-cleavage, we measured sAPP secretion. Alteration of APP processing and BACE proximity by cholesterol might be explained by alterations in cell membrane fluidity...