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Christine P. Hendon - One of the best experts on this subject based on the ideXlab platform.
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Visualization of ex vivo human Ciliated Epithelium and induced flow using optical coherence tomography (Conference Presentation)
Optical Techniques in Pulmonary Medicine II, 2017Co-Authors: Yuye Ling, Xinwen Yao, Ute A. Gamm, Emilio Arteaga-solis, Charles W. Emala, Michael A. Choma, Christine P. HendonAbstract:The Ciliated Epithelium is important to the human respiratory system because it clears mucus that contains harmful microorganisms and particulate matter. We report the ex vivo visualization of human trachea/bronchi Ciliated Epithelium and induced flow characterized by using spectral-domain optical coherence tomography (SD-OCT). A total number of 17 samples from 7 patients were imaged. Samples were obtained from Columbia University Department of Anesthesiology’s tissue bank. After excision, the samples were placed in Gibco Medium 199 solution with oxygen at 4°C until imaging. The samples were maintained at 36.7°C throughout the experiment. The imaging protocol included obtaining 3D volumes and 200 consecutive B-scans parallel to the head-to-feet direction (superior-inferior axis) of the airway, using Thorlabs Telesto system at 1300 nm at 28 kHz A-line rate and a custom built high resolution SDOCT system at 800nm at 32 kHz A-line rate. After imaging, samples were processed with H and E histology. Speckle variance of the time resolved datasets demonstrate significant contrast at the Ciliated Epithelium sites. Flow images were also obtained after injecting 10μm polyester beads into the solution, which shows beads traveling trajectories near the Ciliated Epithelium areas. In contrary, flow images taken in the orthogonal plane show no beads traveling trajectories. This observation is in line with our expectation that cilia drive flow predominantly along the superior-inferior axis. We also observed the protective function of the mucus, shielding the Epithelium from the invasion of foreign objects such as microspheres. Further studies will be focused on the cilia’s physiological response to environmental changes such as drug administration and physical injury.
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Ex vivo visualization of human Ciliated Epithelium and quantitative analysis of induced flow dynamics by using optical coherence tomography.
Lasers in surgery and medicine, 2017Co-Authors: Yuye Ling, Xinwen Yao, Ute A. Gamm, Emilio Arteaga-solis, Charles W. Emala, Michael A. Choma, Christine P. HendonAbstract:BACKGROUND AND OBJECTIVE Cilia-driven mucociliary clearance is an important self-defense mechanism of great clinical importance in pulmonary research. Conventional light microscopy possesses the capability to visualize individual cilia and its beating pattern but lacks the throughput to assess the global ciliary activities and flow dynamics. Optical coherence tomography (OCT), which provides depth-resolved cross-sectional images, was recently introduced to this area. MATERIALS AND METHODS Fourteen de-identified human tracheobronchial tissues are directly imaged by two OCT systems: one system centered at 1,300 nm with 6.5 μm axial resolution and 15 μm lateral resolution, and the other centered at 800 nm with 2.72 μm axial resolution and 5.52 μm lateral resolution. Speckle variance images are obtained in both cross-sectional and volumetric modes. After imaging, sample blocks are sliced along the registered OCT imaging plane and processed with hematoxylin and eosin (H&E) stain for comparison. Quantitative flow analysis is performed by tracking the path-lines of microspheres in a fixed cross-section. Both the flow rate and flow direction are characterized. RESULTS The speckle variance images successfully segment the Ciliated epithelial tissue from its cilia-denuded counterpart, and the results are validated by corresponding H&E stained sections. A further temporal frequency analysis is performed to extract the ciliary beat frequency (CBF) at cilia cites. By adding polyester microspheres as contrast agents, we demonstrate ex vivo imaging of the flow induced by cilia activities of human tracheobronchial samples. CONCLUSION This manuscript presents an ex vivo study on human tracheobronchial Ciliated Epithelium and its induced mucous flow by using OCT. Within OCT images, intact Ciliated Epithelium is effectively distinguished from cilia-denuded counterpart, which serves as a negative control, by examining the speckle variance images. The cilia beat frequency is extracted by temporal frequency analysis. The flow rate, flow direction, and particle throughput are obtained through particle tracking. The availability of these quantitative parameters provides us with a powerful tool that will be useful for studying the physiology, pathophysiology and the effectiveness of therapies on epithelial cilia function, as well as serve as a diagnostic tool for diseases associated with ciliary dysmotility. Lasers Surg. Med. 49:270-279, 2017. © 2017 Wiley Periodicals, Inc.
Michael A. Choma - One of the best experts on this subject based on the ideXlab platform.
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Visualization of ex vivo human Ciliated Epithelium and induced flow using optical coherence tomography (Conference Presentation)
Optical Techniques in Pulmonary Medicine II, 2017Co-Authors: Yuye Ling, Xinwen Yao, Ute A. Gamm, Emilio Arteaga-solis, Charles W. Emala, Michael A. Choma, Christine P. HendonAbstract:The Ciliated Epithelium is important to the human respiratory system because it clears mucus that contains harmful microorganisms and particulate matter. We report the ex vivo visualization of human trachea/bronchi Ciliated Epithelium and induced flow characterized by using spectral-domain optical coherence tomography (SD-OCT). A total number of 17 samples from 7 patients were imaged. Samples were obtained from Columbia University Department of Anesthesiology’s tissue bank. After excision, the samples were placed in Gibco Medium 199 solution with oxygen at 4°C until imaging. The samples were maintained at 36.7°C throughout the experiment. The imaging protocol included obtaining 3D volumes and 200 consecutive B-scans parallel to the head-to-feet direction (superior-inferior axis) of the airway, using Thorlabs Telesto system at 1300 nm at 28 kHz A-line rate and a custom built high resolution SDOCT system at 800nm at 32 kHz A-line rate. After imaging, samples were processed with H and E histology. Speckle variance of the time resolved datasets demonstrate significant contrast at the Ciliated Epithelium sites. Flow images were also obtained after injecting 10μm polyester beads into the solution, which shows beads traveling trajectories near the Ciliated Epithelium areas. In contrary, flow images taken in the orthogonal plane show no beads traveling trajectories. This observation is in line with our expectation that cilia drive flow predominantly along the superior-inferior axis. We also observed the protective function of the mucus, shielding the Epithelium from the invasion of foreign objects such as microspheres. Further studies will be focused on the cilia’s physiological response to environmental changes such as drug administration and physical injury.
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Quantification and visualization of injury and regeneration in the developing Ciliated Epithelium using quantitative flow imaging and speckle variance optical coherence tomography (Conference Presentation)
Optical Techniques in Pulmonary Medicine II, 2017Co-Authors: Ute A. Gamm, Brendan K. Huang, Emily K. Mis, Mustafa K. Khokha, Michael A. ChomaAbstract:Premature infants are at a high risk for respiratory diseases owing to an underdeveloped respiratory system that is very susceptible to infection and inflammation. One aspect of respiratory health is the state of the Ciliated respiratory Epithelium which lines the trachea and bronchi. The Ciliated Epithelium is responsible for trapping and removing pathogens and pollutants from the lungs and an impairment of ciliary functionality can lead to recurring respiratory infections and subsequent lung damage. Mechanisms of cilia-driven fluid flow itself but also factors influenced by development like ciliary density and flow generation are incompletely understood. Furthermore, medical interventions like intubation and accidental aspiration can lead to focal or diffuse loss of cilia and disruption of flow. In this study we use two animal models, Xenopus embryo and ex vivo mouse trachea, to analyze flow defects in the injured Ciliated Epithelium. Injury is generated either mechanically with a scalpel or chemically by calcium chloride (CaCl2) shock, which efficiently but reversibly deciliates the embryo skin. In this study we used optical coherence tomography (OCT) and particle tracking velocimetry (PTV) to quantify cilia driven fluid flow over the surface of the Xenopus embryo. We additionally visualized damage to the Ciliated Epithelium by capturing 3D speckle variance images that highlight beating cilia. Mechanical injury disrupted cilia-driven fluid flow over the injured site, which led to a reduction in cilia-driven fluid flow over the whole surface of the embryo (n=7). The calcium chloride shock protocol proved to be highly effective in deciliating embryos (n=6). 3D speckle variance images visualized a loss of cilia and cilia-driven flow was halted immediately after application. We also applied CaCl2-shock to cultured ex vivo mouse trachea (n=8) and found, similarly to effects in Xenopus embryo, an extensive loss of cilia with resulting cessation of flow. We investigated the regeneration of the Ciliated Epithelium after an 8 day incubation period, and found that cilia had regrown and flow was completely restored. In conclusion, OCT is a valuable tool to visualize injury of the Ciliated Epithelium and to quantify reduction of generated flow. This method allows for systematic investigation of focal and diffuse injury of the Ciliated Epithelium and the assessment of mechanisms to compensate for loss of flow.
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Ex vivo visualization of human Ciliated Epithelium and quantitative analysis of induced flow dynamics by using optical coherence tomography.
Lasers in surgery and medicine, 2017Co-Authors: Yuye Ling, Xinwen Yao, Ute A. Gamm, Emilio Arteaga-solis, Charles W. Emala, Michael A. Choma, Christine P. HendonAbstract:BACKGROUND AND OBJECTIVE Cilia-driven mucociliary clearance is an important self-defense mechanism of great clinical importance in pulmonary research. Conventional light microscopy possesses the capability to visualize individual cilia and its beating pattern but lacks the throughput to assess the global ciliary activities and flow dynamics. Optical coherence tomography (OCT), which provides depth-resolved cross-sectional images, was recently introduced to this area. MATERIALS AND METHODS Fourteen de-identified human tracheobronchial tissues are directly imaged by two OCT systems: one system centered at 1,300 nm with 6.5 μm axial resolution and 15 μm lateral resolution, and the other centered at 800 nm with 2.72 μm axial resolution and 5.52 μm lateral resolution. Speckle variance images are obtained in both cross-sectional and volumetric modes. After imaging, sample blocks are sliced along the registered OCT imaging plane and processed with hematoxylin and eosin (H&E) stain for comparison. Quantitative flow analysis is performed by tracking the path-lines of microspheres in a fixed cross-section. Both the flow rate and flow direction are characterized. RESULTS The speckle variance images successfully segment the Ciliated epithelial tissue from its cilia-denuded counterpart, and the results are validated by corresponding H&E stained sections. A further temporal frequency analysis is performed to extract the ciliary beat frequency (CBF) at cilia cites. By adding polyester microspheres as contrast agents, we demonstrate ex vivo imaging of the flow induced by cilia activities of human tracheobronchial samples. CONCLUSION This manuscript presents an ex vivo study on human tracheobronchial Ciliated Epithelium and its induced mucous flow by using OCT. Within OCT images, intact Ciliated Epithelium is effectively distinguished from cilia-denuded counterpart, which serves as a negative control, by examining the speckle variance images. The cilia beat frequency is extracted by temporal frequency analysis. The flow rate, flow direction, and particle throughput are obtained through particle tracking. The availability of these quantitative parameters provides us with a powerful tool that will be useful for studying the physiology, pathophysiology and the effectiveness of therapies on epithelial cilia function, as well as serve as a diagnostic tool for diseases associated with ciliary dysmotility. Lasers Surg. Med. 49:270-279, 2017. © 2017 Wiley Periodicals, Inc.
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Visualization and quantification of injury to the Ciliated Epithelium using quantitative flow imaging and speckle variance optical coherence tomography
Nature Publishing Group, 2017Co-Authors: Ute A. Gamm, Brendan K. Huang, Emily K. Mis, Mustafa K. Khokha, Michael A. ChomaAbstract:Abstract Mucociliary flow is an important defense mechanism in the lung to remove inhaled pathogens and pollutants. Disruption of ciliary flow can lead to respiratory infections. Multiple factors, from drugs to disease can cause an alteration in ciliary flow. However, less attention has been given to injury of the Ciliated Epithelium. In this study, we show how optical coherence tomography (OCT) can be used to investigate injury to the Ciliated Epithelium in a multi-contrast setting. We used particle tracking velocimetry (PTV-OCT) to investigate the cilia-driven flow field and 3D speckle variance imaging to investigate size and extent of injury caused to the skin of Xenopus embryos. Two types of injuries are investigated, focal injury caused by mechanical damage and diffuse injury by a calcium chloride shock. We additionally investigate injury and regeneration of cilia to calcium chloride on ex vivo mouse trachea. This work describes how OCT can be used as a tool to investigate injury and regeneration in Ciliated Epithelium
Ute A. Gamm - One of the best experts on this subject based on the ideXlab platform.
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Visualization of ex vivo human Ciliated Epithelium and induced flow using optical coherence tomography (Conference Presentation)
Optical Techniques in Pulmonary Medicine II, 2017Co-Authors: Yuye Ling, Xinwen Yao, Ute A. Gamm, Emilio Arteaga-solis, Charles W. Emala, Michael A. Choma, Christine P. HendonAbstract:The Ciliated Epithelium is important to the human respiratory system because it clears mucus that contains harmful microorganisms and particulate matter. We report the ex vivo visualization of human trachea/bronchi Ciliated Epithelium and induced flow characterized by using spectral-domain optical coherence tomography (SD-OCT). A total number of 17 samples from 7 patients were imaged. Samples were obtained from Columbia University Department of Anesthesiology’s tissue bank. After excision, the samples were placed in Gibco Medium 199 solution with oxygen at 4°C until imaging. The samples were maintained at 36.7°C throughout the experiment. The imaging protocol included obtaining 3D volumes and 200 consecutive B-scans parallel to the head-to-feet direction (superior-inferior axis) of the airway, using Thorlabs Telesto system at 1300 nm at 28 kHz A-line rate and a custom built high resolution SDOCT system at 800nm at 32 kHz A-line rate. After imaging, samples were processed with H and E histology. Speckle variance of the time resolved datasets demonstrate significant contrast at the Ciliated Epithelium sites. Flow images were also obtained after injecting 10μm polyester beads into the solution, which shows beads traveling trajectories near the Ciliated Epithelium areas. In contrary, flow images taken in the orthogonal plane show no beads traveling trajectories. This observation is in line with our expectation that cilia drive flow predominantly along the superior-inferior axis. We also observed the protective function of the mucus, shielding the Epithelium from the invasion of foreign objects such as microspheres. Further studies will be focused on the cilia’s physiological response to environmental changes such as drug administration and physical injury.
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Quantification and visualization of injury and regeneration in the developing Ciliated Epithelium using quantitative flow imaging and speckle variance optical coherence tomography (Conference Presentation)
Optical Techniques in Pulmonary Medicine II, 2017Co-Authors: Ute A. Gamm, Brendan K. Huang, Emily K. Mis, Mustafa K. Khokha, Michael A. ChomaAbstract:Premature infants are at a high risk for respiratory diseases owing to an underdeveloped respiratory system that is very susceptible to infection and inflammation. One aspect of respiratory health is the state of the Ciliated respiratory Epithelium which lines the trachea and bronchi. The Ciliated Epithelium is responsible for trapping and removing pathogens and pollutants from the lungs and an impairment of ciliary functionality can lead to recurring respiratory infections and subsequent lung damage. Mechanisms of cilia-driven fluid flow itself but also factors influenced by development like ciliary density and flow generation are incompletely understood. Furthermore, medical interventions like intubation and accidental aspiration can lead to focal or diffuse loss of cilia and disruption of flow. In this study we use two animal models, Xenopus embryo and ex vivo mouse trachea, to analyze flow defects in the injured Ciliated Epithelium. Injury is generated either mechanically with a scalpel or chemically by calcium chloride (CaCl2) shock, which efficiently but reversibly deciliates the embryo skin. In this study we used optical coherence tomography (OCT) and particle tracking velocimetry (PTV) to quantify cilia driven fluid flow over the surface of the Xenopus embryo. We additionally visualized damage to the Ciliated Epithelium by capturing 3D speckle variance images that highlight beating cilia. Mechanical injury disrupted cilia-driven fluid flow over the injured site, which led to a reduction in cilia-driven fluid flow over the whole surface of the embryo (n=7). The calcium chloride shock protocol proved to be highly effective in deciliating embryos (n=6). 3D speckle variance images visualized a loss of cilia and cilia-driven flow was halted immediately after application. We also applied CaCl2-shock to cultured ex vivo mouse trachea (n=8) and found, similarly to effects in Xenopus embryo, an extensive loss of cilia with resulting cessation of flow. We investigated the regeneration of the Ciliated Epithelium after an 8 day incubation period, and found that cilia had regrown and flow was completely restored. In conclusion, OCT is a valuable tool to visualize injury of the Ciliated Epithelium and to quantify reduction of generated flow. This method allows for systematic investigation of focal and diffuse injury of the Ciliated Epithelium and the assessment of mechanisms to compensate for loss of flow.
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Ex vivo visualization of human Ciliated Epithelium and quantitative analysis of induced flow dynamics by using optical coherence tomography.
Lasers in surgery and medicine, 2017Co-Authors: Yuye Ling, Xinwen Yao, Ute A. Gamm, Emilio Arteaga-solis, Charles W. Emala, Michael A. Choma, Christine P. HendonAbstract:BACKGROUND AND OBJECTIVE Cilia-driven mucociliary clearance is an important self-defense mechanism of great clinical importance in pulmonary research. Conventional light microscopy possesses the capability to visualize individual cilia and its beating pattern but lacks the throughput to assess the global ciliary activities and flow dynamics. Optical coherence tomography (OCT), which provides depth-resolved cross-sectional images, was recently introduced to this area. MATERIALS AND METHODS Fourteen de-identified human tracheobronchial tissues are directly imaged by two OCT systems: one system centered at 1,300 nm with 6.5 μm axial resolution and 15 μm lateral resolution, and the other centered at 800 nm with 2.72 μm axial resolution and 5.52 μm lateral resolution. Speckle variance images are obtained in both cross-sectional and volumetric modes. After imaging, sample blocks are sliced along the registered OCT imaging plane and processed with hematoxylin and eosin (H&E) stain for comparison. Quantitative flow analysis is performed by tracking the path-lines of microspheres in a fixed cross-section. Both the flow rate and flow direction are characterized. RESULTS The speckle variance images successfully segment the Ciliated epithelial tissue from its cilia-denuded counterpart, and the results are validated by corresponding H&E stained sections. A further temporal frequency analysis is performed to extract the ciliary beat frequency (CBF) at cilia cites. By adding polyester microspheres as contrast agents, we demonstrate ex vivo imaging of the flow induced by cilia activities of human tracheobronchial samples. CONCLUSION This manuscript presents an ex vivo study on human tracheobronchial Ciliated Epithelium and its induced mucous flow by using OCT. Within OCT images, intact Ciliated Epithelium is effectively distinguished from cilia-denuded counterpart, which serves as a negative control, by examining the speckle variance images. The cilia beat frequency is extracted by temporal frequency analysis. The flow rate, flow direction, and particle throughput are obtained through particle tracking. The availability of these quantitative parameters provides us with a powerful tool that will be useful for studying the physiology, pathophysiology and the effectiveness of therapies on epithelial cilia function, as well as serve as a diagnostic tool for diseases associated with ciliary dysmotility. Lasers Surg. Med. 49:270-279, 2017. © 2017 Wiley Periodicals, Inc.
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Visualization and quantification of injury to the Ciliated Epithelium using quantitative flow imaging and speckle variance optical coherence tomography
Nature Publishing Group, 2017Co-Authors: Ute A. Gamm, Brendan K. Huang, Emily K. Mis, Mustafa K. Khokha, Michael A. ChomaAbstract:Abstract Mucociliary flow is an important defense mechanism in the lung to remove inhaled pathogens and pollutants. Disruption of ciliary flow can lead to respiratory infections. Multiple factors, from drugs to disease can cause an alteration in ciliary flow. However, less attention has been given to injury of the Ciliated Epithelium. In this study, we show how optical coherence tomography (OCT) can be used to investigate injury to the Ciliated Epithelium in a multi-contrast setting. We used particle tracking velocimetry (PTV-OCT) to investigate the cilia-driven flow field and 3D speckle variance imaging to investigate size and extent of injury caused to the skin of Xenopus embryos. Two types of injuries are investigated, focal injury caused by mechanical damage and diffuse injury by a calcium chloride shock. We additionally investigate injury and regeneration of cilia to calcium chloride on ex vivo mouse trachea. This work describes how OCT can be used as a tool to investigate injury and regeneration in Ciliated Epithelium
Yuye Ling - One of the best experts on this subject based on the ideXlab platform.
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Visualization of ex vivo human Ciliated Epithelium and induced flow using optical coherence tomography (Conference Presentation)
Optical Techniques in Pulmonary Medicine II, 2017Co-Authors: Yuye Ling, Xinwen Yao, Ute A. Gamm, Emilio Arteaga-solis, Charles W. Emala, Michael A. Choma, Christine P. HendonAbstract:The Ciliated Epithelium is important to the human respiratory system because it clears mucus that contains harmful microorganisms and particulate matter. We report the ex vivo visualization of human trachea/bronchi Ciliated Epithelium and induced flow characterized by using spectral-domain optical coherence tomography (SD-OCT). A total number of 17 samples from 7 patients were imaged. Samples were obtained from Columbia University Department of Anesthesiology’s tissue bank. After excision, the samples were placed in Gibco Medium 199 solution with oxygen at 4°C until imaging. The samples were maintained at 36.7°C throughout the experiment. The imaging protocol included obtaining 3D volumes and 200 consecutive B-scans parallel to the head-to-feet direction (superior-inferior axis) of the airway, using Thorlabs Telesto system at 1300 nm at 28 kHz A-line rate and a custom built high resolution SDOCT system at 800nm at 32 kHz A-line rate. After imaging, samples were processed with H and E histology. Speckle variance of the time resolved datasets demonstrate significant contrast at the Ciliated Epithelium sites. Flow images were also obtained after injecting 10μm polyester beads into the solution, which shows beads traveling trajectories near the Ciliated Epithelium areas. In contrary, flow images taken in the orthogonal plane show no beads traveling trajectories. This observation is in line with our expectation that cilia drive flow predominantly along the superior-inferior axis. We also observed the protective function of the mucus, shielding the Epithelium from the invasion of foreign objects such as microspheres. Further studies will be focused on the cilia’s physiological response to environmental changes such as drug administration and physical injury.
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Ex vivo visualization of human Ciliated Epithelium and quantitative analysis of induced flow dynamics by using optical coherence tomography.
Lasers in surgery and medicine, 2017Co-Authors: Yuye Ling, Xinwen Yao, Ute A. Gamm, Emilio Arteaga-solis, Charles W. Emala, Michael A. Choma, Christine P. HendonAbstract:BACKGROUND AND OBJECTIVE Cilia-driven mucociliary clearance is an important self-defense mechanism of great clinical importance in pulmonary research. Conventional light microscopy possesses the capability to visualize individual cilia and its beating pattern but lacks the throughput to assess the global ciliary activities and flow dynamics. Optical coherence tomography (OCT), which provides depth-resolved cross-sectional images, was recently introduced to this area. MATERIALS AND METHODS Fourteen de-identified human tracheobronchial tissues are directly imaged by two OCT systems: one system centered at 1,300 nm with 6.5 μm axial resolution and 15 μm lateral resolution, and the other centered at 800 nm with 2.72 μm axial resolution and 5.52 μm lateral resolution. Speckle variance images are obtained in both cross-sectional and volumetric modes. After imaging, sample blocks are sliced along the registered OCT imaging plane and processed with hematoxylin and eosin (H&E) stain for comparison. Quantitative flow analysis is performed by tracking the path-lines of microspheres in a fixed cross-section. Both the flow rate and flow direction are characterized. RESULTS The speckle variance images successfully segment the Ciliated epithelial tissue from its cilia-denuded counterpart, and the results are validated by corresponding H&E stained sections. A further temporal frequency analysis is performed to extract the ciliary beat frequency (CBF) at cilia cites. By adding polyester microspheres as contrast agents, we demonstrate ex vivo imaging of the flow induced by cilia activities of human tracheobronchial samples. CONCLUSION This manuscript presents an ex vivo study on human tracheobronchial Ciliated Epithelium and its induced mucous flow by using OCT. Within OCT images, intact Ciliated Epithelium is effectively distinguished from cilia-denuded counterpart, which serves as a negative control, by examining the speckle variance images. The cilia beat frequency is extracted by temporal frequency analysis. The flow rate, flow direction, and particle throughput are obtained through particle tracking. The availability of these quantitative parameters provides us with a powerful tool that will be useful for studying the physiology, pathophysiology and the effectiveness of therapies on epithelial cilia function, as well as serve as a diagnostic tool for diseases associated with ciliary dysmotility. Lasers Surg. Med. 49:270-279, 2017. © 2017 Wiley Periodicals, Inc.
Ronald Anderson - One of the best experts on this subject based on the ideXlab platform.
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Hyaluronidase augments pneumolysin-mediated injury to human Ciliated Epithelium §
International journal of infectious diseases : IJID : official publication of the International Society for Infectious Diseases, 2006Co-Authors: Candace H. Feldman, Timothy J Mitchell, Riana Cockeran, M.j. Jedrzejas, Ronald AndersonAbstract:Summary Objectives The main objective of this study was to investigate the effects of pneumococcal hyaluronidase (0.1–10μg/ml), alone and in combination with pneumolysin (50 and 100ng/ml), on human Ciliated Epithelium. Methods Ciliary beat frequency (CBF) and structural integrity of human Ciliated respiratory Epithelium in vitro were studied using a phototransistor technique and a visual scoring index, respectively. Results Hyaluronidase per se did not affect either CBF or the structural integrity of the Epithelium. However, preincubation of the epithelial strips with hyaluronidase (10μg/ml) for 30min at 37°C significantly potentiated pneumolysin-mediated ciliary slowing and epithelial damage. Hyaluronan, a substrate of hyaluronidase, had no effects on the Ciliated respiratory Epithelium in concentrations up to 100μg/ml and did not antagonize the injurious effects of pneumolysin on the Epithelium. However, preincubation of the epithelial strips with hyaluronan (100μg/ml) was associated with attenuation of the ciliary slowing and epithelial damage induced by incubation of the strips with hyaluronidase (10μg/ml) for 30min at 37°C followed by addition of pneumolysin (50ng/ml). Conclusions Although having no direct effects alone, hyaluronidase may contribute to pneumolysin-mediated damage and dysfunction to respiratory Epithelium, thereby favoring colonization and subsequently extra-pulmonary dissemination of the pneumococcus.
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Neutrophils Potentiate Platinum-Mediated Injury to Human Ciliated Epithelium In Vitro
Inhalation toxicology, 2005Co-Authors: Charles Feldman, Annette J. Theron, Ronald AndersonAbstract:AbstractExposure to platinum salts, such as may occur in the platinum refining industry, can be associated with the development of airway disorders such as asthma. However, there have been no studies investigating the direct effects of platinum salts on human Ciliated Epithelium. We have investigated the effects of platinic chloride on human Ciliated Epithelium, obtained by brushing the inferior nasal turbinate of healthy human volunteers. Ciliary beat frequency was measured using a phototransistor technique, and damage to the structural integrity of the Epithelium was measured using a visual scoring index. Platinic chloride at concentrations between 0.25 and 25 μ M caused a dose-dependent slowing of ciliary beating and damage to the structural integrity of the Epithelium. These direct injurious effects were not affected by catalase, but were almost completely attenuated by preincubation of the Epithelium with cysteine. The effects of platinic chloride on ciliary beating and structural integrity were enha...
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The effects of pneumolysin and hydrogen peroxide, alone and in combination, on human Ciliated Epithelium in vitro
Respiratory medicine, 2002Co-Authors: Candace H. Feldman, Timothy J Mitchell, Peter J. Cole, Ronald Anderson, Riana Cockeran, Robert WilsonAbstract:Abstract We have investigated the effects of pneumolysin and H 2 O 2 , putative virulence factors of Streptococcus pneumoniae , on the ciliary beat frequency and structural integrity of human Ciliated Epithelium in vitro . Human Ciliated Epithelium was obtained by brushing the inferior nasal turbinate of healthy human volunteers. Ciliary slowing (CS) was measured using a photo-transistor technique and epithelial damage (ED) was documented using a visual scoring index. Effects of recombinant pneumolysin (100 ng/ml), a mutant pneumolysin preparation with markedly reduced haemolytic activity (100 ng/ml) and reagent H 2 O 2 (100 μM) were measured alone and in combination, in the absence and presence of catalase (1000 units/ml). When used individually, both recombinant pneumolysin and H 2 O 2 caused significant ( P 2 O 2 but not those of pneumolysin were almost completely attenuated by catalase, while the mutant pneumolysin preparation did not cause significant CS or ED. When used in combination, the effects of pneumolysin and H 2 O 2 on CS and ED were additive as opposed to synergistic. These actions of pneumolysin and H 2 O 2 may contribute to the pathogenesis of respiratory tract infections caused by the pneumococcus.
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Vitamin E attenuates the injurious effects of bioactive phospholipids on human Ciliated Epithelium in vitro
The European respiratory journal, 2001Co-Authors: Candace H. Feldman, Ronald Anderson, A. J. Theron, Helen C. Steel, C. J. Van Rensburg, P. J. Cole, Robert WilsonAbstract:Bioactive phospholipids (PL), particularly lysophosphatidylcholine (LPC), are being increasingly implicated in the pathogenesis of various acute and chronic inflammatory disorders, particularly those of the airways, while there is emerging evidence that vitamin E may function as a natural antagonist of these lipid mediators of inflammation. The aims of this study were to document the effects of vitamin E on the inhibition of ciliary beating and damage to structural integrity of human Ciliated Epithelium induced by the PL, platelet-activating factor (PAF), lyso-PAF and LPC in vitro in relation to the anti-oxidative and membrane-stabilizing properties of the vitamin. Ciliary beat frequency was measured by a phototransistor technique, and damage to structural integrity assessed by a visual-scoring index, while superoxide production by polymorphonuclear leukocytes and membrane-stabilizing potential were measured using lucigenin-enhanced chemiluminescence and haemolytic procedures, respectively. All three PL caused inhibition of ciliary beating and structural damage to human Ciliated Epithelium by membrane-directed cytotoxic mechanisms, which were potentiated by human polymorphonuclear leukocytes due to induction of oxidant-mediated injury. Both direct and phagocyte-inflicted epithelial injury was attenuated by vitamin E. In haemolytic and chemiluminescence assays, vitamin E neutralized both the membrane-destabilizing and pro-oxidative actions of all three PL, while spectrophotometric analysis of mixtures of vitamin E with PAF, lyso-PAF and LPC revealed alterations in peak intensity, as well as peak shifts, indicative of physicochemical interactions between the vitamin and the PL. Vitamin E status may be a determinant of susceptibility to phospholipid-mediated airway inflammation and damage.