Ce travail a été soutenu par National Eye Institute Grant 1 R15 EY13649-01, et par une subvention à la découverte individuelle de la sciences naturelles et en génie du Canada (CRSNG). Un merci spécial à Deda Gillespie pour l&#39;usinage des métaux, et pour la consultation sur la conception du dispositif et la construction.

<ol>
	<li>Goldreich, D. &. a. m. p. ;. a. m. p., Kanics, I. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tactile+acuity+is+enhanced+in+blindness.">Tactile acuity is enhanced in blindness.</a> J. Neurosci. 23, 3439-3445 (2003).</li><li>Goldreich, D. &. a. m. p. ;. a. m. p., Kanics, I. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Performance+of+blind+and+sighted+humans+on+a+tactile+grating+detection+task.">Performance of blind and sighted humans on a tactile grating detection task.</a> Percept. Psychophys. 68, 1363-1371 (2006).</li><li>Kontsevich, L. L. &. a. m. p. ;. a. m. p., Tyler, C. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Bayesian+adaptive+estimation+of+psychometric+slope+and+threshold.">Bayesian adaptive estimation of psychometric slope and threshold.</a> Vision. Res. 39, 2729-2737 (1999).</li><li>Bleyenheuft, Y., Cols, C., Arnould, C. &. a. m. p. ;. a. m. p., Thonnard, J. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Age-related+changes+in+tactile+spatial+resolution+from+6+to+16+years.">Age-related changes in tactile spatial resolution from 6 to 16 years.</a> Somatosens. Mot. Res. 23, 83-87 (2006).</li><li>Johnson, K. O. &. a. m. p. ;. a. m. p., Phillips, J. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tactile+spatial+resolution.+I.+Two-point+discrimination,+gap+detection,+grating+resolution,+and+letter+recognition.">Tactile spatial resolution. I. Two-point discrimination, gap detection, grating resolution, and letter recognition.</a> J. Neurophysiol. 46, 1177-1192 (1981).</li><li>Gibson, G. O. &. a. m. p. ;. a. m. p., Craig, J. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+effect+of+force+and+conformance+on+tactile+intensive+and+spatial+sensitivity.">The effect of force and conformance on tactile intensive and spatial sensitivity.</a> Exp. Brain Res. 170, 172-181 (2006).</li><li>Johnson, K. O. &. a. m. p. ;. a. m. p., Phillips, J. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+rotating+drum+stimulator+for+scanning+embossed+patterns+and+textures+across+the+skin.">A rotating drum stimulator for scanning embossed patterns and textures across the skin.</a> J. Neurosci. Methods. 22, 221-231 (1988).</li><li>Craig, J. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Grating+orientation+as+a+measure+of+tactile+spatial+acuity.">Grating orientation as a measure of tactile spatial acuity.</a> Somatosens. Mot. Res. 16, 197-206 (1999).</li><li>Killebrew, J. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+dense+array+stimulator+to+generate+arbitrary+spatio-temporal+tactile+stimuli.">A dense array stimulator to generate arbitrary spatio-temporal tactile stimuli.</a> J. Neurosci. Methods. 161, 62-74 (2007).</li></ol>

La livraison contrôlée de l&#39;espace structuré des stimuli mécaniques pose des défis pas confrontés à la prestation des stimuli visuels ou auditifs, dont l&#39;équipement disponible dans le commerce (écrans d&#39;ordinateur, haut-parleurs) peuvent être utilisés. Pour cette raison, de nombreuses expériences de psychophysique tactiles sont toujours fait en utilisant la livraison de relance manuelle. La livraison manuelle des stimuli tactiles prend du temps et exige beaucoup de soin et de la concentration de la part de l&#39;enquêteur. Par exemple, Bleyenheuft et al. 4 du rapport que «l&#39;application manuelle d&#39;environ 1-2 mm de déformation perpendiculaire peau était utilisée ... l&#39;examinateur a été particulièrement attentif à éviter toute contrainte de cisaillement entre la peau et le grillage qui pourrait fausser la mesure. .. &quot; Peut-être parce que la livraison de relance manuelle est relativement lente et la concentration intensive, de nombreuses études utilisant cette méthode ont utilisé oui / non (juste une relance par essai), plutôt que de deux protocoles d&#39;intervalle choix forcé. Malheureusement, même si le plus grand soin est pris, la livraison de relance manuel laisse de nombreux paramètres de stimulation incontrôlée. Ces paramètres incluent la force de relance, la vitesse de déclenchement, la durée et la stabilité de la surface de stimulation sur la peau. Parmi ces paramètres, peut-être mieux étudiés à l&#39;égard de son influence sur les performances est la force de relance. Les humains montrent une amélioration progressive de la discrimination l&#39;orientation grille sur le bout des doigts comme des changements de profondeur d&#39;indentation de 500 à 1200 microns 5; performance est meilleure à 10 grammes vigueur qu&#39;à la force de 50 grammes 1, même si aucune amélioration n&#39;est observée entre 50 grammes et 200 grammes 6. Pour d&#39;autres applications, telles que la détection caillebotis (en distinguant une surface lisse d&#39;une surface rainurée), l&#39;augmentation de la force de manière significative à améliorer la performance sur toute la plage de 10 à 200 grammes 2,6. Pour surmonter ces défis associés aux tests manuels, nous avons développé le système automatisé, les robinets. Notre objectif dans TAPS bâtiment a été de créer un dispositif simple et sécuritaire, polyvalent, efficace et abordable pour l&#39;application contrôlée de stimulation tactile. L&#39;utilisation contrôlée de gravité est un moyen simple et sûr d&#39;appliquer un stimulus tactile. La sécurité est assurée, parce que la force contre la peau ne peut pas excéder celle due à la pesanteur. L&#39;actionneur linéaire puissante ne sert qu&#39;à transférer la force de gravité sur la peau, puis de retirer le contact. L&#39;appareil est polyvalent, car il pourra accueillir toutes les surfaces usinées dans de relance (ou attachée sur) les extrémités des demi-pouce de diamètre des tiges, et peut être programmé pour exécuter une variété de protocoles de psychophysique. TAPS est efficace, car il déploie rapidement les stimuli, et peut fonctionner timesaving algorithmes adaptatifs. Enfin, les composantes de TAPS sont abordables pour les détenteurs de petites subventions. Les moteurs coûtent environ $ 1.500; les composants électriques (à l&#39;exception de l&#39;ordinateur, mais y compris les cartes PCI et de moteur pas à pas le conducteur), environ 6000 $. Une machine de mini-fraisage et accessoires peuvent être achetés pour environ 1000 $, ou un machiniste professionnel peut être embauché à l&#39;usine des pièces de relance et de faire d&#39;autres petites pièces. Nous espérons que ce système sera appliqué par les autres, et servir à promouvoir l&#39;évolution vers des tests tactiles contrôlée, qui ces dernières années a connu des progrès prometteurs 5,7,8,9.

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		<div>
		<table border="1">
		<thead>
		<tr>
		<th>Material Name</th>
		<th>Type</th>
		<th>Company</th>
		<th>Catalogue Number</th>
		<th>Comment</th>
		</tr>
		</thead>
		<tbody>
		
<tr>
<td>Delrin plastic rods 0.5&#x201D; diameter 3&#x201D; long </td>
<td>&nbsp;</td>
<td>Small Parts</td>
<td>ZRD-08</td>
<td>Rods from which the stimulus pieces are made</td>
</tr>
<tr>
<td>Chrome-steel bearing, 0.5" bore diameter</td>
<td>&nbsp;</td>
<td>Small Parts</td>
<td>BR-08-01</td>
<td>Pivot for the rotating rod</td>
</tr>
<tr>
<td>Plastic bearing, 0.5&#x201D; bore, 1.125&#x201D; outer diameter, 0.25&#x201D; thick</td>
<td>&nbsp;</td>
<td>Small Parts</td>
<td>BRP-08-01</td>
<td>Wheel at end of rotating rod</td>
</tr>
<tr>
<td>Fiberglass curtain, 0.75&#x201D; thick</td>
<td>&nbsp;</td>
<td>McMaster-Carr</td>
<td>9781T83</td>
<td>Sound absorbing curtain around lower table</td>
</tr>
<tr>
<td>Silicone O-rings 5/16" inside diameter</td>
<td>&nbsp;</td>
<td>McMaster-Carr</td>
<td>AS568A- 011</td>
<td>To reduce vibration of stimulus pieces</td>
</tr>
<tr>
<td>Anti-Vibration Pads 2"x 2", 93 PSI max </td>
<td>&nbsp;</td>
<td>McMaster-Carr</td>
<td>60105K61</td>
<td>Put under the linear actuator</td>
</tr>
<tr>
<td>Rubber sandwich mounts 1/2" H x 3/8" W </td>
<td>&nbsp;</td>
<td>McMaster-Carr</td>
<td>9378K11</td>
<td>Put under linear actuator base</td>
</tr>
<tr>
<td>Stepper motor Nema 23, 3-stack </td>
<td>&nbsp;</td>
<td>Industrial Devices</td>
<td>S23</td>
<td>For rotating the stimulus disk</td>
</tr>
<tr>
<td>Linear rodless actuator</td>
<td>&nbsp;</td>
<td>Industrial Devices</td>
<td>R2S23N-105A-18-l-M35M</td>
<td>To control rotating bar movement</td>
</tr>
<tr>
<td>1 Hall effect switch &#x201C;normally open&#x201D; config. </td>
<td>&nbsp;</td>
<td>Industrial Devices</td>
<td>RP1</td>
<td>Actuator home sensor</td>
</tr>
<tr>
<td>2 Hall effect switches &#x201C;normally closed&#x201D; config. </td>
<td>&nbsp;</td>
<td>Industrial Devices</td>
<td>RP2</td>
<td>Actuator limit sensors</td>
</tr>
<tr>
<td>Micro switch</td>
<td>&nbsp;</td>
<td>Honeywell</td>
<td>FSG15N1A</td>
<td>Finger force sensor</td>
</tr>
<tr>
<td>Retro-reflective sensor</td>
<td>&nbsp;</td>
<td>Honeywell</td>
<td>FE7B-RB6VG-M</td>
<td>Piece position sensor</td>
</tr>
<tr>
<td>Motor controller board, closed-loop control</td>
<td>&nbsp;</td>
<td>National Instruments</td>
<td>PCI-step-4CX</td>
<td>Mediates communication between computer and Nudrive</td>
</tr>
<tr>
<td>Nudrive stepper motor driver</td>
<td>&nbsp;</td>
<td>National Instruments</td>
<td>Nudrive 4SX-211</td>
<td>Sends command voltages to the linear actuator and disk stepper motors</td>
</tr>
<tr>
<td>Data acquisition board</td>
<td>&nbsp;</td>
<td>National Instruments</td>
<td>PCI-MIO-16E-1</td>
<td>Reads finger force sensor</td>
</tr>
<tr>
<td>LabVIEW</td>
<td>&nbsp;</td>
<td>National Instruments</td>
<td>&nbsp;</td>
<td>Programming language</td>
</tr>
<tr>
<td>Valuemotion library</td>
<td>&nbsp;</td>
<td>National Instruments</td>
<td>&nbsp;</td>
<td>Motor control routines</td>
</tr>
<tr>
<td>Photoelectric sensor</td>
<td>&nbsp;</td>
<td>Panasonic</td>
<td>PM-K53-C1</td>
<td>Disk home sensor</td>
</tr>
<tr>
<td>Mini milling machine</td>
<td>&nbsp;</td>
<td>Sherline</td>
<td>2010-DRO</td>
<td>For machining the stimulus surfaces</td>
</tr>
<tr>
<td>Ohaus precision mass set</td>
<td>&nbsp;</td>
<td>Edmund Scientific</td>
<td>&nbsp;</td>
<td>Mass on rotating bar</td>
</tr>
<tr>
<td>Parrish Magic Line aluminum cake pan bottom, 9&#x201D; diam.</td>
<td>&nbsp;</td>
<td>Sur La Table</td>
<td>&nbsp;</td>
<td>Rotating disk machined with square cut-outs to hold the stimulus pieces</td>
</tr>		</tbody>
		</table>
		</div>

a tactile automated passive-finger stimulator (taps)

Bien que les tests d&#39;acuité spatiale tactiles sont utilisés dans la recherche en neuroscience et l&#39;évaluation clinique, quelques dispositifs automatisés existent pour la livraison contrôlée stimuli spatialement structuré à la peau. Par conséquent, les enquêteurs appliquent souvent des stimuli tactiles manuellement. L&#39;application de relance manuelle est temps, exige un grand soin et la concentration de la part de l&#39;enquêteur, et laisse de nombreux paramètres de stimulation incontrôlée. Nous décrivons ici un système contrôlé par ordinateur stimulus tactile, le tactile automatisé Passif doigt Stimulateur (TAPS), qui s&#39;applique dans l&#39;espace des stimuli structurés pour la peau, en contrôlant la vitesse de déclenchement, la force de contact, et la durée de contact. TAPS est un appareil polyvalent, système programmable, capable de mener efficacement une variété de procédures psychophysiques. Nous décrivons les composants des robinets, et montrer comment TAPS est utilisée pour administrer un intervalle de deux choix forcé de test d&#39;orientation tactiles grille. Auteur correspondant: Daniel Goldreich

Watch this Scientific Journal Video about A Tactile Automated Passive-Finger Stimulator TAPS at JoVE.com

A Tactile Automated Passive-Finger Stimulator TAPS

Nous décrivons un dispositif commandé par ordinateur pour étudier le sens du toucher: le tactile automatisé Passif doigt Stimulateur (TAPS). Nous décrivons les composants des robinets, et montrer comment TAPS est utilisée pour administrer un intervalle de deux choix forcé de test d&#39;orientation tactiles grille.

Un tactile automatisé Passif doigts stimulateur (TAPS)

Although tactile spatial acuity tests are used in both neuroscience research and clinical assessment, few automated devices exist for delivering ...

a-tactile-automated-passive-finger-stimulator-taps

Research

JoVE Journal

Biology

A Tactile Automated Passive-Finger Stimulator (TAPS)

13.6K vues.  Duquesne University. Nous décrivons un dispositif commandé par ordinateur pour étudier le sens du toucher: le tactile automatisé Passif doigt Stimulateur (TAPS). Nous décrivons les composants des robinets, et montrer comment TAPS est utilisée pour administrer un intervalle de deux choix forcé de test d'orientation tactiles grille.

Vidéo: A Tactile Automated Passive-Finger Stimulator TAPS

Semi-automated Optical Heartbeat Analysis of Small Hearts

We have developed a method for analyzing high speed optical recordings from Drosophila, zebrafish and embryonic mouse hearts (Fink, et. al., 2009). Our Semi-automatic Optical Heartbeat Analysis (SOHA) uses a novel movement detection algorithm that is able to detect cardiac movements associated with individual contractile and relaxation events. The program provides a host of physiologically relevant readouts including systolic and diastolic intervals, heart rate, as well as qualitative and quantitative measures of heartbeat arrhythmicity. The program also calculates heart diameter measurements during both diastole and systole from which fractional shortening and fractional area changes are calculated. Output is provided as a digital file compatible with most spreadsheet programs. Measurements are made for every heartbeat in a record increasing the statistical power of the output. We demonstrate each of the steps where user input is required and show the application of our methodology to the analysis of heart function in all three genetically tractable heart models.

We have developed a Semi-automated Optical Heartbeat Analysis method (SOHA) for analyzing high speed optical recordings from Drosophila, zebrafish and embryonic mouse hearts. We demonstrate the application of our methodology to the analysis of heart function in fruit fly and embryonic mouse hearts.

Analyse semi-automatisée Heartbeat optique de petits coeurs

We have developed a method for analyzing high speed optical recordings from Drosophila, zebrafish and embryonic mouse hearts (Fink, et. al., 2009). Our ...

Recherche

Biologie

Digital Microfluidics for Automated Proteomic Processing

Clinical proteomics has emerged as an important new discipline, promising the discovery of biomarkers that will be useful for early diagnosis and prognosis of disease. While clinical proteomic methods vary widely, a common characteristic is the need for (i) extraction of proteins from extremely heterogeneous fluids (i.e. serum, whole blood, etc.) and (ii) extensive biochemical processing prior to analysis. Here, we report a new digital microfluidics (DMF) based method integrating several processing steps used in clinical proteomics. This includes protein extraction, resolubilization, reduction, alkylation and enzymatic digestion. Digital microfluidics is a microscale fluid-handling technique in which nanoliter-microliter sized droplets are manipulated on an open surface. Droplets are positioned on top of an array of electrodes that are coated by a dielectric layer - when an electrical potential is applied to the droplet, charges accumulate on either side of the dielectric. The charges serve as electrostatic handles that can be used to control droplet position, and by biasing a sequence of electrodes in series, droplets can be made to dispense, move, merge, mix, and split on the surface. Therefore, DMF is a natural fit for carrying rapid, sequential, multistep, miniaturized automated biochemical assays. This represents a significant advance over conventional methods (relying on manual pipetting or robots), and has the potential to be a useful new tool in clinical proteomics.
Mais J. Jebrail, Vivienne N. Luk, and Steve C. C. Shih contributed equally to this work.
Sergio L. S. Freire's current address is at the University of the Sciences in Philadelphia located at 600 South 43rd Street, Philadelphia, PA 19104.

Digital Microfluidics is a technique characterized by the manipulation of discrete droplets (~nL - mL) on an array of electrodes by the application of electrical fields. It is well-suited for carrying out rapid, sequential, miniaturized automated biochemical assays. Here, we report a platform capable of automating several proteomic processing steps.

Microfluidique numérique pour le traitement automatisé protéomiques

Clinical proteomics has emerged as an important new discipline, promising the discovery of biomarkers that will be useful for early diagnosis and ...

Development of automated imaging and analysis for zebrafish chemical screens.

We demonstrate the application of image-based high-content screening (HCS) methodology to identify small molecules that can modulate the FGF/RAS/MAPK pathway in zebrafish embryos. The zebrafish embryo is an ideal system for in vivo high-content chemical screens. The 1-day old embryo is approximately 1mm in diameter and can be easily arrayed into 96-well plates, a standard format for high throughput screening. During the first day of development, embryos are transparent with most of the major organs present, thus enabling visualization of tissue formation during embryogenesis. The complete automation of zebrafish chemical screens is still a challenge, however, particularly in the development of automated image acquisition and analysis. We previously generated a transgenic reporter line that expresses green fluorescent protein (GFP) under the control of FGF activity and demonstrated their utility in chemical screens 1. To establish methodology for high throughput whole organism screens, we developed a system for automated imaging and analysis of zebrafish embryos at 24-48 hours post fertilization (hpf) in 96-well plates 2. In this video we highlight the procedures for arraying transgenic embryos into multiwell plates at 24hpf and the addition of a small molecule (BCI) that hyperactivates FGF signaling 3. The plates are incubated for 6 hours followed by the addition of tricaine to anesthetize larvae prior to automated imaging on a Molecular Devices ImageXpress Ultra laser scanning confocal HCS reader. Images are processed by Definiens Developer software using a Cognition Network Technology algorithm that we developed to detect and quantify expression of GFP in the heads of transgenic embryos. In this example we highlight the ability of the algorithm to measure dose-dependent effects of BCI on GFP reporter gene expression in treated embryos.

We report the development of a system for automated imaging and analysis of zebrafish transgenic embryos in multiwell plates. This demonstrates the ability to measure dose dependent effects of a small molecule, BCI, on Fibroblast Growth Factor reporter gene expression and provide technology for establishing high-throughput zebrafish chemical screens.

Développement de l&#39;imagerie automatisée et d&#39;analyse pour les écrans chimiques du poisson zèbre.

We demonstrate the application of image-based high-content screening (HCS) methodology to identify small molecules that can modulate the FGF/RAS/MAPK ...

Using an Automated Cell Counter to Simplify Gene Expression Studies: siRNA Knockdown of IL-4 Dependent Gene Expression in Namalwa Cells

The use of siRNA mediated gene knockdown is continuing to be an important tool in studies of gene expression.  siRNA studies are being conducted not only to study the effects of downregulating single genes, but also to interrogate signaling pathways and other complex interaction networks.  These pathway analyses require both the use of relevant cellular models and methods that cause less perturbation to the cellular physiology.  Electroporation is increasingly being used as an effective way to introduce siRNA and other nucleic acids into difficult to transfect cell lines and primary cells without altering the signaling pathway under investigation. There are multiple critical steps to a successful siRNA experiment, and there are ways to simplify the work while improving the data quality at several experimental stages.  To help you get started with your siRNA mediated gene knockdown project, we will demonstrate how to perform a pathway study complete from collecting and counting the cells prior to electroporation through post transfection real-time PCR gene expression analysis.  The following study investigates the role of the transcriptional activator STAT6 in IL-4 dependent gene expression of CCL17 in a Burkitt lymphoma cell line (Namalwa).  The techniques demonstrated are useful for a wide range of siRNA-based experiments on both adherent and suspension cells.  We will also show how to streamline cell counting with the TC10 automated cell counter, how to electroporate multiple samples simultaneously using the MXcell electroporation system, and how to simultaneously assess RNA quality and quantity with the Experion automated electrophoresis system.

This procedure describes a quick and easy workflow to introduce siRNA into difficult to transfect cell lines and follow gene expression by real-time PCR. Use of an automated cell counter, multi-well electroporation plate, and automated electrophoresis station provide quick and reliable results without the need for expensive robotic handling.

Aide d&#39;un compteur de cellules automatisé pour simplifier les études d&#39;expression génique: Knockdown siRNA de l&#39;IL-4 dans l&#39;expression des gènes dépendant cellules Namalwa

The use of siRNA mediated gene knockdown is continuing to be an important tool in studies of gene expression.  siRNA studies are being conducted not only ...

Semi-automated Imaging of Tissue-specific Fluorescence in Zebrafish Embryos

Zebrafish embryos are a powerful tool for large-scale screening of small molecules. Transgenic zebrafish that express fluorescent reporter proteins are frequently used to identify chemicals that modulate gene expression. Chemical screens that assay fluorescence in live zebrafish often rely on expensive, specialized equipment for high content screening. We describe a procedure using a standard epifluorescence microscope with a motorized stage to automatically image zebrafish embryos and detect tissue-specific fluorescence. Using transgenic zebrafish that report estrogen receptor activity via expression of GFP, we developed a semi-automated procedure to screen for estrogen receptor ligands that activate the reporter in a tissue-specific manner. In this video we describe procedures for arraying zebrafish embryos at 24-48 hours post fertilization (hpf) in a 96-well plate and adding small molecules that bind estrogen receptors. At 72-96 hpf, images of each well from the entire plate are automatically collected and manually inspected for tissue-specific fluorescence. This protocol demonstrates the ability to detect estrogens that activate receptors in heart valves but not in liver.

Described here is a protocol for semi-automated imaging of tissue-specific fluorescence in zebrafish embryos.

Imagerie semi-automatique de la fluorescence spécifique de tissu dans embryons de poissons zèbres

Zebrafish embryos are a powerful tool for large-scale screening of small molecules. Transgenic zebrafish that express fluorescent reporter proteins are ...

Automated Analysis of Dynamic Ca2+ Signals in Image Sequences

Intracellular Ca2+ signals are commonly studied with fluorescent Ca2+ indicator dyes and microscopy techniques. However, quantitative analysis of Ca2+ imaging data is time consuming and subject to bias. Automated signal analysis algorithms based on region of interest (ROI) detection have been implemented for one-dimensional line scan measurements, but there is no current algorithm which integrates optimized identification and analysis of ROIs in two-dimensional image sequences. Here an algorithm for rapid acquisition and analysis of ROIs in image sequences is described. It utilizes ellipses fit to noise filtered signals in order to determine optimal ROI placement, and computes Ca2+ signal parameters of amplitude, duration and spatial spread. This algorithm was implemented as a freely available plugin for ImageJ (NIH) software. Together with analysis scripts written for the open source statistical processing software R, this approach provides a high-capacity pipeline for performing quick statistical analysis of experimental output. The authors suggest that use of this analysis protocol will lead to a more complete and unbiased characterization of physiologic Ca2+ signaling.

Automated Analysis of Dynamic Ca2+ Signals in Image Sequences

Here a novel region of interest analysis protocol based on sorting best-fit ellipses assigned to regions of positive signal within two-dimensional time lapse image sequences is demonstrated. This algorithm may enable investigators to comprehensively analyze physiological Ca2+ signals with minimal user input and bias.

Analyse automatisée de dynamique Ca<sup&gt; 2 +</sup&gt; Signaux de séquences d&#39;images

Intracellular Ca2+ signals are commonly studied with fluorescent Ca2+ indicator dyes and microscopy techniques. However, quantitative analysis of Ca2+ ...

High-resolution Time-lapse Imaging and Automated Analysis of Microtubule Dynamics in Living Human Umbilical Vein Endothelial Cells

The physiological process by which new vasculature forms from existing vasculature requires specific signaling events that trigger morphological changes within individual endothelial cells (ECs). These processes are critical for homeostatic maintenance such as wound healing, and are also crucial in promoting tumor growth and metastasis. EC morphology is defined by the organization of the cytoskeleton, a tightly regulated system of actin and microtubule (MT) dynamics that is known to control EC branching, polarity and directional migration, essential components of angiogenesis. To study MT dynamics, we used high-resolution fluorescence microscopy coupled with computational image analysis of fluorescently-labeled MT plus-ends to investigate MT growth dynamics and the regulation of EC branching morphology and directional migration. Time-lapse imaging of living Human Umbilical Vein Endothelial Cells (HUVECs) was performed following transfection with fluorescently-labeled MT End Binding protein 3 (EB3) and Mitotic Centromere Associated Kinesin (MCAK)-specific cDNA constructs to evaluate effects on MT dynamics. PlusTipTracker software was used to track EB3-labeled MT plus ends in order to measure MT growth speeds and MT growth lifetimes in time-lapse images. This methodology allows for the study of MT dynamics and the identification of how localized regulation of MT dynamics within sub-cellular regions contributes to the angiogenic processes of EC branching and migration.

Protocols for Human Umbilical Vein Endothelial Cell (HUVEC) culture, transient transfection of fluorescently-labeled markers of microtubule growth, live-cell imaging and automated analysis of interphase microtubule growth dynamics are detailed.

Haute résolution Time-lapse d&#39;imagerie et d&#39;analyse automatisée des microtubules Dynamics Living ombilicale humaine Cellules endothéliales de veine

The physiological process by which new vasculature forms from existing vasculature requires specific signaling events that trigger morphological changes ...

Open Source High Content Analysis Utilizing Automated Fluorescence Lifetime Imaging Microscopy

We present an open source high content analysis instrument utilizing automated fluorescence lifetime imaging (FLIM) for assaying protein interactions using F&#246;rster resonance energy transfer (FRET) based readouts of fixed or live cells in multiwell plates. This provides a means to screen for cell signaling processes read out using intramolecular FRET biosensors or intermolecular FRET of protein interactions such as oligomerization or heterodimerization, which can be used to identify binding partners. We describe here the functionality of this automated multiwell plate FLIM instrumentation and present exemplar data from our studies of HIV Gag protein oligomerization and a time course of a FRET biosensor in live cells. A detailed description of the practical implementation is then provided with reference to a list of hardware components and a description of the open source data acquisition software written in &#181;Manager. The application of FLIMfit, an open source MATLAB-based client for the OMERO platform, to analyze arrays of multiwell plate FLIM data is also presented. The protocols for imaging fixed and live cells are outlined and a demonstration of an automated multiwell plate FLIM experiment using cells expressing fluorescent protein-based FRET constructs is presented. This is complemented by a walk-through of the data analysis for this specific FLIM FRET data set.

We present an open source high content analysis (HCA) instrument utilizing automated fluorescence lifetime imaging (FLIM) for assaying protein interactions using F&#246;rster resonance energy transfer (FRET) based readouts. Data acquisition for this openFLIM-HCA instrument is controlled by software written in &#181;Manager and data analysis is undertaken in FLIMfit.

Open Source Content Haute Analyse Utilisant automatisé Fluorescence Lifetime Imaging Microscopy

We present an open source high content analysis instrument utilizing automated fluorescence lifetime imaging (FLIM) for assaying protein interactions ...

A Rapid Automated Protocol for Muscle Fiber Population Analysis in Rat Muscle Cross Sections Using Myosin Heavy Chain Immunohistochemistry

Quantification of muscle fiber populations provides a deeper insight into the effects of disease, trauma, and various other influences on skeletal muscle composition. Various time-consuming methods have traditionally been used to study fiber populations in many fields of research. However, recently developed immunohistochemical methods based on myosin heavy chain protein expression provide a quick alternative to identify multiple fiber types in a single section. Here, we present a rapid, reliable and reproducible protocol for improved staining quality, allowing automatic acquisition of whole cross sections and automatic quantification of fiber populations with ImageJ. For this purpose, embedded skeletal muscles are cut in cross sections, stained using myosin heavy chains antibodies with secondary fluorescent antibodies and DAPI for cell nuclei staining. Whole cross sections are then scanned automatically using a slide scanner to obtain high-resolution composite pictures of the entire specimen. Fiber population analyses are subsequently performed to quantify slow, intermediate and fast fibers using an automated macro for ImageJ. We have previously shown that this method can identify fiber populations reliably to a degree of &#177;4%. In addition, this method reduces inter-user variability and time per analyses significantly using the open source platform ImageJ.

Here, we present a protocol for rapid muscle fiber analyses, which allows improved staining quality, and thereby automatic acquisition and quantification of fiber populations using the freely available software ImageJ.

Un protocole automatisé pour l&#39;analyse rapide de la population de fibre musculaire chez le rat Muscle Sections Cross Utilisation myosine chaîne lourde immunohistochimie

Quantification of muscle fiber populations provides a deeper insight into the effects of disease, trauma, and various other influences on skeletal muscle ...

Measuring the Confluence of iPSCs Using an Automated Imaging System

This study focuses on understanding how growing iPSCs on different ECM coating substrates can affect cell confluence. A protocol to assess iPSC confluence in real time has been established without the need to count cells in single cell suspension to avoid any growth perturbation. A high-content image analysis system was used to assess iPCS confluence on 4 different ECMs over time in an automated manner. Different analysis settings were used to assess cell confluence of adherent iPSCs and only a slight difference (at 24 and 48 hours with laminin) has been observed whether a 60, 80 or 100% mask was applied. We also show that laminin lead to the best confluence compared to Matrigel, vitronectin and fibronectin.

The goal of the protocol is to compare different extracellular matrix (ECM) coating conditions to assess how differential coating affects the growth rate of induced pluripotent stem cells (iPSCs). In particular, we aim to set up conditions to obtain optimal growth of iPSC cultures.

Mesure de la confluence des CSPi à l’aide d’un système d’imagerie automatisé.

This study focuses on understanding how growing iPSCs on different ECM coating substrates can affect cell confluence. A protocol to assess iPSC confluence ...