Valoración mecánica de la contracción muscular con TMG. Tiempo de Contracción según los genotipos del gen ACTN3

La proteína α-actinina-3, sintetizada por el gen ACTN3, estabiliza los sarcómeros y permite una mayor capacidad de transmisión de la fuerza en las fibras musculares rápidas, tipo II [1]. Pero sólo la sintentizan los portadores de los genotipos RR y RX, y no lo hacen los portadores del XX. La Tensiomiografía (TMG) es un instrumento que electroestimulando el músculo permite analizar sus características mecánicas [2]; utilizando un sensor que mide el desplazamiento radial debido a la contracción y los tiempos que tarda en producirse. El objetivo de este trabajo es estudiar la asociación del tiempo de contracción (Tc) del músculo vasto lateral con los genotipos de ACTN3. Métodos. El diseño del estudio fue comparativo. Se contó con una muestra de 53 estudiantes universitarios (21,92 ± 3.16 años; 1,76 ± 0,11 m y 71,97 ± 9,52 kg). El genotipado de la muestra se llevó a cabo mediante QPCR usando protocolos de discriminación alélica, con el software CFX Manager. Se utilizó un tensiomiógrafo TMG-BMC para medir los músculos vastos laterales con una descarga de corriente de 110 mA de intensidad durante un milisegundo, analizando el Tc. Se calcularon las medias del Tc de ambas piernas, y se realizaron comparaciones mediante las pruebas U Mann Whitney y H Kruskal Wallis. Resultados. Se observaron diferencias significativas en el Tc del vasto lateral en los portadores del genotipo RR, tanto al analizar el efecto principal, como al compararlo frente al genotipo codominante XX y dominante RX+XX (Tabla 1). En todos ellos, los portadores del genotipo RR presentaron valores inferiores de Tc.Universidad Europea (2012/UEM01); Cátedra Real Madrid (2013/10RM)No data (2016)UE

Visualization 1: Fast frame scanning camera system for light-sheet microscopy

Video of the flowing fluorescent beads in aqueous solution. Originally published in Applied Optics on 10 October 2015 (ao-54-29-8632

Two-Photon Laser Scanning Stereomicroscopy for Fast Volumetric Imaging

<div><p>Bessel beams have been successfully used in two-photon laser scanning fluorescence microscopy to extend the depth of field (EDF), which makes it possible to observe fast events volumetrically. However, the depth information is lost due to integration of fluorescence signals along the propagation direction. We describe the design and implementation of two-photon lasers scanning stereomicroscopy, which allows viewing dynamic processes in three-dimensional (3D) space stereoscopically in real-time with shutter glasses at the speed of 1.4 volumes per second. The depth information can be appreciated by human visual system or be recovered with correspondence algorithms for some cases.</p></div

Software control framework based on ScanImage.

<p>(a) Modules modified (in red boxes) based on ScanImage workflow (from “Start” to “End”, see [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0168885#pone.0168885.ref022" target="_blank">22</a>] for details). (b). List of all the modified files of ScanImage.</p

Feature-based correspondence algorithm and the recovered depth.

<p>(a) 87 circular objects found in the left image (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0168885#pone.0168885.g005" target="_blank">Fig 5c1</a>). (b) The corresponding circular objects are found in the right image (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0168885#pone.0168885.g005" target="_blank">Fig 5c2</a>). (c) The corresponding circular objects are also found in the z-projection of the stack (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0168885#pone.0168885.g005" target="_blank">Fig 5d</a>) to determine the ground truth depths. (d) Comparing the recovered depths from the stereo-pair and the ground truth values from the image stack.</p

Volumetric imaging of dynamic samples and 3D Reconstruction.

<p>The fluorescent beads are moved at an average speed of about 1 μm/s by driving the sample stage. See <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0168885#pone.0168885.s007" target="_blank">S1 Movie</a> for the dynamic tracking.</p

Volumetric imaging and 3D reconstruction.

<p>Stereo-pairs of (a-b) pollen grains and (c) fluorescent beads were captured in stereo-mode. (d) Sum projection of the stack along z-axis. (e) 5 selected images from an image stack consisting of 87 slices taken in standard two-photon mode. (f) 3D map of objects with their depth recovered from the stereo-pair in (c). Each object is labeled according to its depth error with a color map that spans from green to red. Blue spheres are unrecognized objects in (e), but are present in (d). (g) Histogram of the depth error with superposed normal distribution (red line). Scale bars in (a)-(e) are all 10μm.</p

Simulated and measured two-photon excitation PSF2p of Bessel beams with small tilted angle (≈2.5°).

<p>(a) Numerical simulation. Scale bar 20μm. (b) Measured PSF2p. (c) PSF2p with Gaussian beam. Scale bar 1μm. (d). Lateral FWHM of PSF2p. (e) Axial intensity distribution along beam direction at different z position.</p

Pushing a silica microsphere out of the focus with the focused TEM₀₀ beam.

<p>Using a long working distance microscope objective (20X/NA0.6). (Video S2).</p

Calculated trapping efficiencies of a spherical particle by annular beams with different widths.

<p><b>A.</b> Axial trapping efficiency, <b>B.</b> lateral trapping efficiency. The trapping wavelength is 491 nm, the sphere radius is 2 µm, and the numerical aperture of the objective is 0.6.</p