A5069400888- Spectroscopy Techniques in Biomedical and Chemical Research
- Advanced Fluorescence Microscopy Techniques
- Optical Coherence Tomography Applications
- Photoacoustic and Ultrasonic Imaging
- Cell Image Analysis Techniques
- Spectroscopy and Chemometric Analyses
- Photoreceptor and optogenetics research
- Neurogenesis and neuroplasticity mechanisms
- Photonic Crystal and Fiber Optics
- Neuroinflammation and Neurodegeneration Mechanisms
- Neuroscience and Neuropharmacology Research
- Nerve injury and regeneration
- Advancements in Transdermal Drug Delivery
- Multiple Sclerosis Research Studies
- Cellular Mechanics and Interactions
- Image Processing Techniques and Applications
- Additive Manufacturing and 3D Printing Technologies
- Advanced Neuroimaging Techniques and Applications
- Dendrimers and Hyperbranched Polymers
- Optical measurement and interference techniques
- Alzheimer's disease research and treatments
- 3D Printing in Biomedical Research
- Near-Field Optical Microscopy
- Optical Imaging and Spectroscopy Techniques
- Conducting polymers and applications
University of Calgary
2015-2024
Ontario Brain Institute
2012-2020
Allen Institute for Brain Science
2018
University of Ottawa
2007-2012
University of Connecticut
2007
Technological advancements in biology and microscopy have empowered a transition from bioimaging as an observational method to quantitative one. However, biologists are adopting these experiments become more complex, researchers need additional expertise carry out this work rigorous reproducible manner. This Essay provides navigational guide for experimental aid understanding of sample preparation through image acquisition, analysis, data interpretation. We discuss the interconnectedness...
As an extension of the brain, spinal cord has unique properties which could allow us to gain a better understanding CNS pathology. The brain and share same cellular components, yet latter is simpler in cytoarchitecture connectivity. In Alzheimer's research, virtually all focus on pathology, however it been shown that transgenic mouse models accumulate beta amyloid plaques cord, suggesting possesses molecular machinery conditions for plaque formation. Here we report spatial-temporal map load...
The cuprizone (CPZ) model allows the study of biochemical processes underlying nonautoimmune-mediated demyelination, remyelination, and chronic white matter disease progression. CPZ is a copper (Cu) chelator that chiefly causes oligodendrocyte apoptosis in corpus callosum cerebellum when administered mouse diet. While disruption Cu homeostasis known to cause neurodegeneration (as observed Wilson’s Menkes disease), no consensus exists date as CPZ’s mechanism action. We sought determine...
We demonstrate coherent anti-Stokes Raman scattering (CARS) microscopy of lipid-rich structures using a single unamplified femtosecond Ti:sapphire laser and photonic crystal fiber (PCF) with two closely lying zero dispersion wavelengths (ZDW) for the Stokes source. The primary enabling factor fast data acquisition (84 micros per pixel) in proof-of-principle CARS images, is low noise supercontinuum (SC) generated this type PCF, contrast to SC PCF one ZDW. dependence pulse on average input...
Dendrimers and dendriplexes, highly branched synthetic macromolecules, have gained popularity as new tools for a variety of nanomedicine strategies due to their unique structure properties. We show that fluorescent phosphorus dendrimers are well retained by bone marrow‐derived macrophages exhibit robust spectral shift in its emission response polarization conditions. Fluorescence properties this marker can also assist identifying macrophage presence phenotype status at different time points...
N- and P/Q-type voltage-gated Ca
We demonstrate a novel miniaturized multimodal coherent anti-Stokes Raman scattering (CARS) microscope based on microelectromechanical systems (MEMS) scanning mirrors and custom miniature optics. A single Ti:sapphire femtosecond pulsed laser is used as the light source to produce CARS, two photon excitation fluorescence (TPEF) second harmonic generation (SHG) images using this microscope. The high resolution distortion-free obtained from various samples such USAF target, fluorescent...
We demonstrate for the first time, a portable multimodal coherent anti-Stokes Raman scattering microscope (exoscope) minimally invasive in-vivo imaging of tissues. This device is based around micro-electromechanical system scanning mirror and miniaturized optics with light delivery accomplished by photonic crystal fibre. A single Ti:sapphire femtosecond pulsed laser used as source to produce CARS, two photon excitation fluorescence second harmonic generation images. The high resolution...
ABSTRACT Introduction : Neurotransmitter‐dependent signaling is traditionally restricted to axon terminals. However, receptors are present on myelinating glia, suggesting that chemical transmission may also occur along axons. Methods Confocal microscopy and Ca 2+ ‐imaging using an axonally expressed FRET‐based reporter was used measure changes morphological alterations in myelin response stimulation of glutamate receptors. Results Activation α‐amino‐3‐hydroxy‐5‐methyl‐4‐isoxazolepropionic...
Multiple sclerosis white matter exhibits widespread biochemical lipid pathology of myelin measured by label-free spectral CARS microscopy.
Prognostics, which refers to the inference of an expected time failure for a system, is made difficult by need track and predict trajectories real-valued system parameters over essentially unbounded domains prescribe subset these in alarm should be raised. In this paper, we propose idea, one whereby problems are avoided: Instead physical or sensor parameters, vector corresponding probabilities system's sensors (which course bounded within unit hypercube) tracked. With help diagnosis model,...
Spectral focusing is a well-established technique for increasing spectral resolution in coherent Raman scattering microscopy. However, current methods tuning optical chirp setups using focusing, such as glass rods, gratings, and prisms, are very cumbersome, time-consuming to use, difficult align, all of which limit more widespread use the technique. Here, we report stimulated (SRS) configuration can rapidly tune by utilizing compact adjustable-dispersion TIH53 blocks. By varying height...
OBJECTIVE Intravital spectral imaging of the large, deeply situated nerves in rat peripheral nervous system (PNS) has not been well described. Here, authors have developed a highly stable platform for performing tibial nerve live rodents, thus allowing capture high-resolution, high-magnification images requiring long acquisition times. By further exploiting qualities topically applied myelin dye Nile red, this technique is capable visualizing detailed microenvironment demyelination injury...
Laser-scanning optical microscopes generally do not control the polarization of exciting laser field. We show that and imaging mode (confocal versus two photon) exert a profound influence on ability to detect [Formula: see text] changes in both cultured neurons living myelin. With two-photon excitation, increasing ellipticity resulted reduction resting X-Rhod-1 fluorescence homogeneous bulk solution, cell cytoplasm, In contrast, varying angle linearly polarized field only had appreciable...
Coherent anti-Stokes Raman scattering (CARS) generates a strong label-free signal in the long wavenumber C─H stretching region. Lipid-rich myelinated tissues, such as brain and spinal cord, would appear to be ideal subjects for imaging with CARS laser-scanning microscopy. However, highly ordered, biochemically complex, nature of tissues complicate use technique. A microscopy approach is presented that overcomes challenges tissue achieve chemically orientationally sensitive high-resolution images.
Laser-scanning non-linear optical techniques such as multi-photon fluorescence excitation microscopy (MPM), Second/ Third Harmonic Generation (SHG/THG), and Coherent Anti-Stokes Raman Scattering (CARS) are being utilized in research laboratories worldwide. The efficiencies of these effects dependent on the polarization state light relative to orientation sample imaged. In highly ordered anisotropic biological samples this effect can become pronounced have a dramatic impact imaging...
To obtain accurate, reproducible, and interpretable data when conducting imaging experiments, it is critical to consider external factors affecting acquisition at various steps of the experimental workflow. Illumination power stability represent two factors, especially comparing fluorescence intensities between images during a time-lapse experiment or experiments performed different times on microscopes. The signal can be generated by types light sources. These sources their coupling...
The current trend in laser sources for Coherent Anti-Stokes Raman Scattering (CARS) microscopy consists of picosecond optical parametric oscillators (OPO)s and femtosecond-pumped fiber supercontinuum sources. While both methods are proven CARS performers, restricted wavelength tuning range low power limit the lines types samples that may be practically interrogated. To address these limitations, we present a novel, highly tunable spectrally focused femtosecond Optical Parametric Amplifier...
The pathology of multiple sclerosis (MS) involves both the gray and white matter regions brain spinal cord. It is characterized by various combinations demyelination, inflammatory infiltration, axonal degeneration, later gliosis in chronic lesions. While acute plaques are well easily identified, evidence indicates that CNS MS patients may be globally altered, with subtle abnormalities found grossly normal appearing (NAWM) diffusely abnormal (DAWM) where histochemical stains advanced magnetic...
Abstract Mitochondria have their own genome (mtDNA), which is present in hundreds of copies per cell and organized into nucleoid structures that are distributed throughout the dynamic mitochondrial network. Beyond encoding essential protein subunits for oxidative phosphorylation, mtDNA can also serve as a signalling molecule when it cytosol. Despite importance this genome, there still many unknowns with respect to its regulation. To study dynamics living cells, we developed genetic...
As multiphoton microscopy increases in popularity users with diverse backgrounds are exploring new applications for the technique. With most recent 'turnkey' systems now on market a typical user no longer has to be laser physicist or engineer employ system their research. However, some basic understanding of mechanisms non-linear excitation will allow optimize his improved performance extend it applications.
The pathology of multiple sclerosis involves the gray and white matter regions brain spinal cord often characterized by various combinations demyelination, inflammatory infiltration, axonal degeneration, later gliosis in chronic lesions. While acute lesions are well easily identified, evidence indicates that CNS MS patients may be globally altered, with subtle abnormalities found grossly normal appearing (NAWM) histochemical stains magnetic resonance imaging only indicating a general...