Publications by authors named "Jason S Jones"

4 Publications

  • Page 1 of 1

Calcium Imaging of Cardiomyocytes in the Beating Mouse Heart With Multiphoton Microscopy.

Front Physiol 2018 31;9:969. Epub 2018 Jul 31.

Nancy E. and Peter C. Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY, United States.

Understanding the microscopic dynamics of the beating heart has been challenging due to the technical nature of imaging with micrometer resolution while the heart moves. The development of multiphoton microscopy has made , cell-resolved measurements of calcium dynamics and vascular function possible in motionless organs such as the brain. In heart, however, studies of interactions between cells and the native microenvironment are behind other organ systems. Our goal was to develop methods for intravital imaging of cardiac structural and calcium dynamics with microscopic resolution. Ventilated mice expressing GCaMP6f, a genetically encoded calcium indicator, received a thoracotomy to provide optical access to the heart. Vasculature was labeled with an injection of dextran-labeled dye. The heart was partially stabilized by a titanium probe with a glass window. Images were acquired at 30 frames per second with spontaneous heartbeat and continuously running, ventilated breathing. The data were reconstructed into three-dimensional volumes showing tissue structure, vasculature, and GCaMP6f signal in cardiomyocytes as a function of both the cardiac and respiratory cycle. We demonstrated the capability to simultaneously measure calcium transients, vessel size, and tissue displacement in three dimensions with micrometer resolution. Reconstruction at various combinations of cardiac and respiratory phase enabled measurement of regional and single-cell cardiomyocyte calcium transients (GCaMP6f fluorescence). GCaMP6f fluorescence transients in individual, aberrantly firing cardiomyocytes were also quantified. Comparisons of calcium dynamics (rise-time and tau) at varying positions within the ventricle wall showed no significant depth dependence. This method enables studies of coupling between contraction and excitation during physiological blood perfusion and breathing at high spatiotemporal resolution. These capabilities could lead to a new understanding of normal and disease function of cardiac cells.
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http://dx.doi.org/10.3389/fphys.2018.00969DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6079295PMC
July 2018

Label-free imaging of atherosclerotic plaques using third-harmonic generation microscopy.

Biomed Opt Express 2018 01 13;9(1):214-229. Epub 2017 Dec 13.

Nancy E. and Peter C. Meinig School of Biomedical Engineering, Cornell University, 526 N. Campus Rd., Ithaca, NY 14853, USA.

Multiphoton microscopy using laser sources in the mid-infrared range (MIR, 1,300 nm and 1,700 nm) was used to image atherosclerotic plaques from murine and human samples. Third harmonic generation (THG) from atherosclerotic plaques revealed morphological details of cellular and extracellular lipid deposits. Simultaneous nonlinear optical signals from the same laser source, including second harmonic generation and endogenous fluorescence, resulted in label-free images of various layers within the diseased vessel wall. The THG signal adds an endogenous contrast mechanism with a practical degree of specificity for atherosclerotic plaques that complements current nonlinear optical methods for the investigation of cardiovascular disease. Our use of whole-mount tissue and backward scattered epi-detection suggests THG could potentially be used in the future as a clinical tool.
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http://dx.doi.org/10.1364/BOE.9.000214DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5772576PMC
January 2018

Simultaneous optical and electrical in vivo analysis of the enteric nervous system.

Nat Commun 2016 06 7;7:11800. Epub 2016 Jun 7.

School of Electrical and Computer Engineering, Cornell University, Ithaca, New York 14853, USA.

The enteric nervous system (ENS) is a major division of the nervous system and vital to the gastrointestinal (GI) tract and its communication with the rest of the body. Unlike the brain and spinal cord, relatively little is known about the ENS in part because of the inability to directly monitor its activity in live animals. Here, we integrate a transparent graphene sensor with a customized abdominal window for simultaneous optical and electrical recording of the ENS in vivo. The implanted device captures ENS responses to neurotransmitters, drugs and optogenetic manipulation in real time.
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http://dx.doi.org/10.1038/ncomms11800DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4899629PMC
June 2016

Three-photon excited fluorescence imaging of unstained tissue using a GRIN lens endoscope.

Biomed Opt Express 2013 May 1;4(5):652-8. Epub 2013 Apr 1.

School of Applied and Engineering Physics, Cornell University, 146 Clark Hall, Ithaca, NY 14853, USA ; These authors contributed equally to this work.

We present a compact and portable three-photon gradient index (GRIN) lens endoscope system suitable for imaging of unstained tissues, potentially deep within the body, using a GRIN lens system of 1 mm diameter and 8 cm length. The lateral and axial resolution in water is 1.0 μm and 9.5 μm, respectively. The ~200 μm diameter field of view is imaged at 2 frames/s using a fiber-based excitation source at 1040 nm. Ex vivo imaging is demonstrated with unstained mouse lung at 5.9 mW average power. These results demonstrate the feasibility of three-photon GRIN lens endoscopy for optical biopsy.
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http://dx.doi.org/10.1364/BOE.4.000652DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3646593PMC
May 2013