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Hosy E.,Institut Universitaire de France | Hosy E.,French National Center for Scientific Research | Butler C.,Institut Universitaire de France | Butler C.,French National Center for Scientific Research | And 3 more authors.
Current Opinion in Chemical Biology | Year: 2014

Progresses in microscopy have often led to major discoveries in neuroscience, and the recent advent of super-resolution microscopy is no exception. In this review, we will show how imaging has advanced our modern vision of synaptic function. More particularly, we will emphasize how novel nanoscopy techniques have helped in deciphering the organization of post-synaptic proteins, offering new insight into the mechanism of synaptic transmission. © 2014 Elsevier Ltd.

Idir M.,Brookhaven National Laboratory | Dovillaire G.,Imagine Optic Inc. | Mercere P.,Synchrotron Soleil
Synchrotron Radiation News | Year: 2013

In recent years, there has been growing interest in the design of electron accelerators in order to reduce beam emittance and to increase photon brilliance (from third-generation synchrotron sources to free electron lasers). This has increased the coherent properties of the beam and has opened up new branches of microscopy and spectroscopy at nanometer-length scales. The X-ray nano probe is going to be an important tool for future research, hence there has been substantial research carried out in order to develop nano focusing optics of diffraction-limited performance. © 2013 Copyright Taylor and Francis Group, LLC.

Choi H.,Massachusetts Institute of Technology | Tzeranis D.S.,Massachusetts Institute of Technology | Cha J.W.,Massachusetts Institute of Technology | Clemenceau P.,Imagine Optic Inc. | And 6 more authors.
Optics Express | Year: 2012

Fluorescence and phosphorescence lifetime imaging are powerful techniques for studying intracellular protein interactions and for diagnosing tissue pathophysiology. While lifetime-resolved microscopy has long been in the repertoire of the biophotonics community, current implementations fall short in terms of simultaneously providing 3D resolution, high throughput, and good tissue penetration. This report describes a new highly efficient lifetime-resolved imaging method that combines temporal focusing wide-field multiphoton excitation and simultaneous acquisition of lifetime information in frequency domain using a nanosecond gated imager from a 3D-resolved plane. This approach is scalable allowing fast volumetric imaging limited only by the available laser peak power. The accuracy and performance of the proposed method is demonstrated in several imaging studies important for understanding peripheral nerve regeneration processes. Most importantly, the parallelism of this approach may enhance the imaging speed of long lifetime processes such as phosphorescence by several orders of magnitude. © 2012 Optical Society of America.

Cha J.W.,Massachusetts Institute of Technology | Ballesta J.,Imagine Optic Inc. | So P.T.C.,Massachusetts Institute of Technology
Journal of Biomedical Optics | Year: 2010

The imaging depth of two-photon excitation fluorescence microscopy is partly limited by the inhomogeneity of the refractive index in biological specimens. This inhomogeneity results in a distortion of the wavefront of the excitation light. This wavefront distortion results in image resolution degradation and lower signal level. Using an adaptive optics system consisting of a Shack-Hartmann wavefront sensor and a deformable mirror, wavefront distortion can be measured and corrected. With adaptive optics compensation, we demonstrate that the resolution and signal level can be better preserved at greater imaging depth in a variety of ex-vivo tissue specimens including mouse tongue muscle, heart muscle, and brain. However, for these highly scattering tissues, we find signal degradation due to scattering to be a more dominant factor than aberration. © 2010 Society of Photo- Optical Instrumentation Engineers.

Izeddin I.,University Pierre and Marie Curie | Izeddin I.,Ecole Normale Superieure de Paris | El Beheiry M.,University Pierre and Marie Curie | Andilla J.,Imagine Optic Inc. | And 4 more authors.
Optics Express | Year: 2012

We present a novel approach for three-dimensional localization of single molecules using adaptive optics. A 52-actuator deformable mirror is used to both correct aberrations and induce two-dimensional astigmatism in the point-spread-function. The dependence of the z-localization precision on the degree of astigmatism is discussed. We achieve a z-localization precision of 40 nm for fluorescent proteins and 20 nm for fluorescent dyes, over an axial depth of ∼800 nm. We illustrate the capabilities of our approach for three-dimensional high-resolution microscopy with superresolution images of actin filaments in fixed cells and single-molecule tracking of quantum-dot labeled transmembrane proteins in live HeLa cells. © 2012 Optical Society of America.

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