Correlative two-color two-photon (2C2P) excitation STED microscopy.

We present a two-color two-photon stimulated emission depletion microscopy technique (2C2P-STED) that correlates a confocal image with a super-resolved image employing the inherent self-referencing mechanism of nonlinear excitation. The novel approach overcomes the substantial challenge posed by two different imaging modalities in laser-scanning fluorescence microscopy for colocalization on the nanometer scale. Demonstrating the principle of 2C2P-STED, we show for the first time super-resolved images of the gram-positive bacteria TIGR4 pilus type-1.

Age related changes in cell stiffness of tendon stem/progenitor cells and a rejuvenating effect of ROCK-inhibition.

Tendon stem/progenitor cells (TSPC) are potential targets for regenerative medicine and the treatment of tendon injuries. The frequency of such injuries increases in elderly patients while the proportion of functional TSPCs in tendon tissue decreases, protracting tendon repair. Using atomic force microscopy (AFM), we show that cell stiffness and size increase in TSPCs isolated from elderly patients (A-TSPC) compared to TSPCs from younger patients (Y-TSPC).

Resolution of spectral focusing in coherent Raman imaging.

In this manuscript, we present a detailed investigation of the impact of dispersion on the spectral resolution achievable by the application of spectral focusing in coherent Raman imaging. Our results reveal the detrimental effect of third order dispersion that limits the resolution for group delay dispersion of 100 000 fs and more. Experimental examples for the exact determination of the described effects are given as well as a condensed presentation of the known equations.