scholarly journals Microarray analyzer based on wide field fluorescent microscopy with laser illumination and a device for speckle suppression

2017 ◽  
Vol 8 (11) ◽  
pp. 4798 ◽  
Author(s):  
Yuri Lysov ◽  
Victor Barsky ◽  
Dmitriy Urasov ◽  
Roman Urasov ◽  
Alecksey Cherepanov ◽  
...  
Keyword(s):  
Fluorescent Microscopy ◽  
Wide Field ◽  
Laser Illumination ◽  
Speckle Suppression

scholarly journals DG-CA3 circuitry mediates hippocampal representations of latent information

2019 ◽  
Author(s):  
Alexandra T. Keinath ◽  
Andres Nieto-posadas ◽  
Jennifer C. Robinson ◽  
Mark P. Brandon
Keyword(s):  
Navigation System ◽  
Fluorescent Microscopy ◽  
Pattern Separation ◽  
Wide Field ◽  
Complex Environments ◽  
Sensory Inputs ◽  
Future Goals ◽  
Large Ensembles ◽  
Behavioral Paradigm

AbstractSurvival in complex environments necessitates a flexible navigation system that incorporates memory of recent behavior and associations. Yet, how the hippocampal spatial circuit represents latent information independent of sensory inputs and future goals has not been determined. To address this, we imaged the activity of large ensembles in subregion CA1 via wide-field fluorescent microscopy during a novel behavioral paradigm. Our results demonstrated that latent information is represented through reliable firing rate changes during unconstrained navigation. We then hypothesized that the representation of latent information in CA1 is mediated by pattern separation/completion processes instantiated upstream within the dentate gyrus (DG) and CA3 subregions. Indeed, CA3 ensemble recordings revealed an analogous code for latent information. Moreover, selective chemogenetic inactivation of DG-CA3 circuitry completely and reversibly abolished the CA1 representation of latent information. These results reveal a causal and specific role of DG-CA3 circuitry in the maintenance of latent information within the hippocampus.

Errors and distortion induced under some operating conditions in a confocal laser scanning microscope (CLSM)

1992 ◽  
Vol 50 (1) ◽  
pp. 782-783
Author(s):  
Harry Leung ◽  
Gwendolyn Jeun
Keyword(s):  
Laser Scanning ◽  
Fluorescent Microscopy ◽  
Confocal Laser Scanning Microscope ◽  
Operating Conditions ◽  
Confocal Laser ◽  
Aperture Diameter ◽  
Laser Illumination ◽  
Fluorescent Beads ◽  
Inverted Microscope ◽  
Level Detector

Fluorescent beads have been recommended and used frequently as calibration standards for fluorescent microscopy. However, during our work with a CLSM we observed that images of these beads varied in diameter with dianges in illumination level, detector aperture diameter, and signal amplification (gain). In addition, XZ images showed distortion in proportion to such changes.Images from 9 μm fluorescent beads (Excitation Max. @ 458 nm) were collected with a BIORAD MRC600 CLSM attached to a Nikon Diaphot-TMD inverted microscope. A Nikon Planapo 60x (NA=1.4) oil immersion objective was used in all experiments. The beads were embedded in 5 % gelatin to prevent drifting. Using an illuminating wavelength of 488 nm, the beads were optically sectioned at their equators under varying conditions of laser illumination, detector aperture diameter and gain. To eliminate image variations due to size differences among the beads, all images in Fig 1 were collected from the same bead. Those in Fig 2 were from another similar sized bead.

The spatial organization and extraction of the wall-forming bodies ofEimeria maxima

Parasitology ◽  
2013 ◽  
Vol 140 (7) ◽  
pp. 876-887 ◽  
Author(s):  
SONJA FRÖLICH ◽  
MICHAEL JOHNSON ◽  
MICHELLE ROBINSON ◽  
ROLF ENTZEROTH ◽  
MICHAEL WALLACH
Keyword(s):  
Spatial Organization ◽  
Fluorescent Microscopy ◽  
Three Dimensional ◽  
Wide Field ◽  
Oocyst Wall ◽  
Apicomplexan Parasites ◽  
Sds Page ◽  
Interest In Research

SUMMARYEimeria maximahas been used as a model apicomplexan parasite to study sexual stage development and oocyst wall formation. A complete understanding of the wall's biochemical and biophysical properties is of great interest in research on all apicomplexan parasites. Purified gametocytes, zygotes and oocysts were analysed by three-dimensional confocal microscopy, and wide-field fluorescent microscopy was used to investigate the appearance and spatial organization of the 2 types of wall-forming bodies (WFBs). In addition, a variety of staining procedures and immunoassays were used to assess the biosynthesis, metabolic activity, intactness and molecular composition of the WFBsin situ. WFBs were extracted from gametocytes/zygotes and their composition was assessed by microscopy and SDS-PAGE analysis. It was concluded that isolated gametocytes are intact and metabolically active. Additionally, it was observed that the Type 1 WFBs are aligned at the periphery of the parasite and fuse together producing neutral lipid rich patches that appear to be inserted into the space between 2 parasite-specific membranes. Finally, it was shown that the WFBs extracted from purified gametocytes had the same shape, size and staining properties as those observedin situ, and contained the major glycoprotein antigens known to be present in these organelles.

scholarly journals Multi-plane, wide-field fluorescent microscopy for biodynamic imaging in vivo

2019 ◽  
Vol 10 (12) ◽  
pp. 6625 ◽  
Author(s):  
Ruheng Shi ◽  
Cheng Jin ◽  
Hao Xie ◽  
Yuanlong Zhang ◽  
Xinyang Li ◽  
...  
Keyword(s):  
Fluorescent Microscopy ◽  
Wide Field

scholarly journals Wide-field imaging of cortical neuronal activity with red-shifted functional indicators during motor task execution

2018 ◽  
Author(s):  
Elena Montagni ◽  
Francesco Resta ◽  
Emilia Conti ◽  
Alessandro Scaglione ◽  
Maria Pasquini ◽  
...  
Keyword(s):  
Neuronal Activity ◽  
Cortical Neurons ◽  
Fluorescent Protein ◽  
Fluorescent Microscopy ◽  
Motor Task ◽  
Free Calcium ◽  
Wide Field ◽  
Task Execution ◽  
Additional Advantage

AbstractIntracellular concentration of free calcium ions in neuronal populations can be longitudinally evaluated by using fluorescent protein indicators, called genetically encoded calcium indicators (GECIs). GECIs with long emission wavelengths are particularly attractive for deep tissue microscopy in vivo, and have the additional advantage of avoiding spectral overlap with commonly used neuronal actuators like Channelrhodopsin.Here we investigated the performances of selected red-shifted GECIs through an ex vivo characterization and in vivo imaging of cortical mouse activity during motor task execution. Cortical neurons were infected with adeno-associated virus (AAV) expressing one of the red GECI variants (jRCaMP1a, jRCaMP1b, jRGECO1a, jRGECO1b). First we characterized the transfection in terms of extension and intensity using wide-field fluorescence microscopy. Next, we used RCaMP1a to analyse the cortical neuronal activity during motor behaviour. To that end, wide-field fluorescent microscopy and a robotic device for motor control were combined for simultaneous recording of cortical neuronal-activity, force applied and forelimb position during task execution.Our results show that jRCaMP1a has sufficient sensitivity to monitor in vivo neuronal activity over multiple functional areas, and can be successfully used to perform longitudinal imaging in awake mice.

scholarly journals Wide-field lensless fluorescent microscopy using a tapered fiber-optic faceplate on a chip

The Analyst ◽  
2011 ◽  
Vol 136 (17) ◽  
pp. 3512 ◽  
Author(s):  
Ahmet F. Coskun ◽  
Ikbal Sencan ◽  
Ting-Wei Su ◽  
Aydogan Ozcan
Keyword(s):  
Fiber Optic ◽  
Fluorescent Microscopy ◽  
Wide Field ◽  
Tapered Fiber

scholarly journals Fast laser speckle suppression with an intracavity diffuser

Nanophotonics ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 129-136
Author(s):  
Simon Mahler ◽  
Yaniv Eliezer ◽  
Hasan Yılmaz ◽  
Asher A. Friesem ◽  
Nir Davidson ◽  
...  
Keyword(s):  
Laser Emission ◽  
Laser Speckle ◽  
Integration Time ◽  
Lasing Spectrum ◽  
Time Resolved ◽  
Full Field ◽  
Laser Illumination ◽  
Transverse Modes ◽  
Field Imaging ◽  
Speckle Suppression

AbstractFast speckle suppression is crucial for time-resolved full-field imaging with laser illumination. Here, we introduce a method to accelerate the spatial decoherence of laser emission, achieving speckle suppression in the nanosecond integration time scale. The method relies on the insertion of an intracavity phase diffuser into a degenerate cavity laser to break the frequency degeneracy of transverse modes and broaden the lasing spectrum. The ultrafast decoherence of laser emission results in the reduction of speckle contrast to 3% in less than 1 ns.

scholarly journals SPITFIR(e): A supermaneuverable algorithm for restoring 2D-3D fluorescence images and videos, and background subtraction

2022 ◽  
Author(s):  
Sylvain Prigent ◽  
Hoai-Nam Nguyen ◽  
Ludovic Leconte ◽  
Cesar Augusto Valades-Cruz ◽  
Bassam Hajj ◽  
...  
Keyword(s):  
Fluorescent Microscopy ◽  
Direct Consequence ◽  
Light Sheet ◽  
Stimulated Emission ◽  
Wide Field ◽  
Modern Biology ◽  
Microscopy Imaging ◽  
Cell Behaviors ◽  
Primal Dual ◽  
Restoration Algorithms

While fluorescent microscopy imaging has become the spearhead of modern biology as it is able to generate long-term videos depicting 4D nanoscale cell behaviors, it is still limited by the optical aberrations and the photon budget available in the specimen and to some extend to photo-toxicity. A direct consequence is the necessity to develop flexible and "off-road" algorithms in order to recover structural details and improve spatial resolution, which is critical when pushing the illumination to the low levels in order to limit photo-damages. Moreover, as the processing of very large temporal series of images considerably slows down the analysis, special attention must be paid to the feasibility and scalability of the developed restoration algorithms. To address these specifications, we present a very flexible method designed to restore 2D-3D+Time fluorescent images and subtract undesirable out-of-focus background. We assume that the images are sparse and piece-wise smooth, and are corrupted by mixed Poisson-Gaussian noise. To recover the unknown image, we consider a novel convex and non-quadratic regularizer Sparse Hessian Variation) defined as the mixed norms which gathers image intensity and spatial second-order derivatives. This resulting restoration algorithm named SPITFIR(e) (SParse fIT for Fluorescence Image Restoration) utilizes the primal-dual optimization principle for energy minimization and can be used to process large images acquired with varied fluorescence microscopy modalities. It is nearly parameter-free as the practitioner needs only to specify the amount of desired sparsity (weak, moderate, high). Experimental results in lattice light sheet, stimulated emission depletion, multifocus microscopy, spinning disk confocal, and wide-field microscopy demonstrate the generic ability of the SPITFIR(e) algorithm to efficiently reduce noise and blur, and to subtract undesirable fluorescent background, while avoiding the emergence of deconvolution artifacts.

Wide-field optically sectioning fluorescence microscopy with laser illumination

2000 ◽  
Vol 197 (1) ◽  
pp. 1-4 ◽  
Author(s):  
Neil ◽  
Squire ◽  
Juskaitis ◽  
Bastiaens ◽  
Wilson
Keyword(s):  
Fluorescence Microscopy ◽  
Wide Field ◽  
Laser Illumination
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