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BRATTLEBORO, VT, United States

Merriam L.A.,University of Vermont | Locknar S.A.,Omega Optical Inc. | Girard B.M.,University of Vermont | Parsons R.L.,University of Vermont
American Journal of Physiology - Cell Physiology | Year: 2010

Prior studies indicated that a Ca2+-dependent release of ATP can be initiated from the soma of sympathetic neurons dissociated from guinea pig stellate ganglia. Previous studies also indicated that Ca2+-induced Ca2+ release (CICR) can modulate membrane excitability in these same neurons. As Ca2+ release from internal stores is thought to support somatodendritic transmitter release in other neurons, the present study investigated whether CICR is essential for somatic ATP release from dissociated sympathetic neurons. Caffeine increased intracellular Ca2+ and activated two inward currents: a slow inward current (SIC) in 85% of cells, and multiple faster inward currents [asynchronous transient inward currents (ASTICs)] in 40% of cells voltage-clamped to negative potentials. Caffeine evoked both currents when cells were bathed in a Ca2+-deficient solution, indicating that both were initiated by Ca2+ release from ryanodine-sensitive stores in the endoplasmic reticulum. Sodium influx contributed to generation of both SICs and ASTICs, but only ASTICs were inhibited by the presence of the P2X receptor blocker PPADs. Thus ASTICs, but not SICs, resulted from an ATP activation of P2X receptors. Ionomycin induced ASTICs in a Ca2+-containing solution, but not when it was applied in a Ca2+-deficient solution, demonstrating the key requirement for external Ca2+ in initiating ASTICs by ionomycin. Pretreatment with drugs to deplete the internal stores of Ca2+ did not block the ability of ionomycin or long depolarizing voltage steps to initiate ASTICs. Although a caffeine-induced release of Ca2+ from internal stores can elicit both SICs and ASTICs in dissociated sympathetic neurons, CICR is not required for the somatic release of ATP. Copyright © 2010 the American Physiological Society.

Omega Optical Inc. | Entity website

Omega Optical, Inc. 21 Omega Drive Brattleboro, VT 05301USA U ...

Omega Optical Inc. | Entity website

A fresh approach to order sorting with block, patterned, absorbing, and linearly variable filters. In response to the miniaturization of optical systems and sensors, Omega has taken a fresh approach to an old problem order sorting filters ...

Agency: Department of Health and Human Services | Branch: | Program: SBIR | Phase: Phase I | Award Amount: 99.97K | Year: 2008

DESCRIPTION (provided by applicant): A fast, cost-effective multispectral confocal imaging capability for high-resolution mapping in vivo will be created during this project. This new approach will be based on fiber Bragg gratings, a technology not utiliz ed previously in biomedical imaging, and will ultimately enable the early in vivo detection and treatment of cancer at the cellular level. The central innovation in this effort involves coupling a fast optical fiber-based spectrum analyzer with confocal sp atial scanning optics - both interfaced with endoscopes for in-vivo detection and potential treatments. This fiber optic imaging spectrometer can acquire spectra in microseconds - fast enough to collect one spectrum for each resolved spot in a confocal spa tial scan. As a result, datacubes containing spatial images for many wavelengths can be acquired in real-time. Multispectral confocal imaging in milliseconds will eliminate the effects of motion in biological systems. One can envisage acquiring multiple sp atially registered simultaneous movies, comparing one channel with another (by subtraction or normalization). Further, biomedical researchers could use this new technology to catalog more extensive libraries of spectral images showing tumor growth, angiogenesis and subsequent metastasis. These enhanced libraries will lead to several applications in surgical pathology, oncology labs, and clinics. Clinicians will use the technology to take optical biopsies, perform treatments, and monitor long-term re sults. Patients will have access to real-time diagnosis and treatment. In addition to cancer interventions, other potential multispectral applications include: neural imaging, intra-cellular proteomics, micro-vascular testing, plaque detection, foodstuff t esting, and the evaluation of pharmaceutical products. Our planned phases for this program will successively (a) create a fast fiber grating based spectrometer, (b) integrate the spectrometer with confocal scanning optics, (c) evaluate the integrat ed system with representative ex-vivo and in-vivo tissue samples (normal and abnormal), and (d) deliver the final product optimized for intrasurgical imaging to the biomedical community. The project will rely heavily on the unique and complementary experti se of the two participating groups/organizations.

Carver G.E.,Omega Optical Inc. | Locknar S.A.,Omega Optical Inc. | Morrison W.A.,Omega Optical Inc. | Farkas D.L.,University of Southern California | Farkas D.L.,Spectral Molecular Imaging, Inc.
Progress in Biomedical Optics and Imaging - Proceedings of SPIE | Year: 2014

A new approach for generating high-speed multispectral images has been previously reported by our team. The central concept is that spectra can be acquired for each pixel in a confocal spatial laser scan by using a fast spectrometer based on optical fiber delay lines. This method merges fast spectroscopy with standard spatial scanning to create image datacubes in real time. The datacubes can be analyzed to define regions of interest (ROIs) containing diseased tissue. Firmware and software have been developed for selectively scanning these ROIs with increased optical power. This enables real time image-guided laser treatment with a spatial resolution of a few microns. © 2014 SPIE.

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