Patents by Inventor Chunhui Xu

Chunhui Xu has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20090047739
    Abstract: This invention provides a new procedure for generating cardiomyocyte lineage cells from embryonic stem cells for use in regenerative medicine. Differentiating by way of embryoid body formation or in serum is no longer required. Instead, the stem cells are plated onto a solid substrate, and differentiated in the presence of select factors and morphogens. After enrichment for cells with the appropriate phenotype, the cells are allowed to cluster into Cardiac Bodies™, which are remarkably homogeneous and suitable for the treatment of heart disease.
    Type: Application
    Filed: September 15, 2008
    Publication date: February 19, 2009
    Inventors: Joseph D. Gold, Mohammad Hassanipour, Lila R. Collins, Chunhui Xu
  • Publication number: 20090017465
    Abstract: This invention provides populations human cells of the cardiomyocyte lineage. The cells are obtained by causing cultures of pluripotent stem cells to differentiate in vitro, and then harvesting cells with certain phenotypic features. Differentiated cells bear cell surface and morphologic markers characteristic of cardiomyocytes, and a proportion of them undergo spontaneous periodic contraction. Highly enriched populations of cardiomyocytes and their replicating precursors can be obtained, suitable for use in a variety of applications, such as drug screening and therapy for cardiac disease.
    Type: Application
    Filed: September 22, 2008
    Publication date: January 15, 2009
    Inventor: Chunhui Xu
  • Publication number: 20080299582
    Abstract: This disclosure provides an improved system for culturing human pluripotent stem cells. Traditionally, pluripotent stem cells are cultured on a layer of feeder cells (such as mouse embryonic fibroblasts) to prevent them from differentiating. In the system described here, the role of feeder cells is replaced by components added to the culture environment that support rapid proliferation without differentiation. Effective features are a suitable support structure for the cells, and an effective medium that can be added fresh to the culture without being preconditioned by another cell type. Culturing human embryonic stem cells in fresh medium according to this invention causes the cells to expand surprisingly rapidly, while retaining the ability to differentiate into cells representing all three embryonic germ layers. This new culture system allows for bulk proliferation of pPS cells for commercial production of important products for use in drug screening and human therapy.
    Type: Application
    Filed: July 9, 2008
    Publication date: December 4, 2008
    Inventors: Ramkumar Mandalam, Chunhui Xu, Joseph D. Gold, Melissa K. Carpenter
  • Patent number: 7460785
    Abstract: An optical performance monitor (OPM), e.g., for use in an optical network. The OPM may be configured to characterize one or more impairments in an optical signal modulated with data. The OPM has an optical autocorrelator configured to sample the autocorrelation function of the optical signal, e.g., using two-photon absorption. Autocorrelation points at various bit delays independently or in combination with average optical power may be used to detect and/or quantify one or more of the following: loss of data modulation, signal contrast, pulse broadening, peak power fluctuations, timing jitter, and deviations from the pseudo-random character of data. In addition, the OPM may be configured to perform Fourier transformation based on the autocorrelation points to obtain corresponding spectral components. The spectral components may be used to detect and/or quantify one or more of chromatic dispersion, polarization mode dispersion, and misalignment of a pulse carver and data modulator.
    Type: Grant
    Filed: March 28, 2002
    Date of Patent: December 2, 2008
    Assignee: Lucent Technologies Inc.
    Inventors: Mihaela Dinu, Hernando Garcia, Daniel Kilper, Wayne H. Knox, Howard R. Stuart, Chunhui Xu
  • Patent number: 7455983
    Abstract: This disclosure provides an improved system for culturing human pluripotent stem cells. Traditionally, pluripotent stem cells are cultured on a layer of mouse embryonic fibroblast feeder cells to prevent them from differentiating. In the system described here, the role of feeder cells is replaced by defined components added to the culture environment that support rapid proliferation without differentiation. The medium contains an isotonic buffer, a blend of essential nutrients such as protein and lipids, and an effective growth factor or combination of factors that promote proliferation while inhibiting differentiation. Culturing human embryonic stem cells in fresh medium on an extracellular matrix according to this invention causes the cells to expand surprisingly rapidly, while retaining the ability to differentiate into cells representing all three embryonic germ layers.
    Type: Grant
    Filed: September 24, 2004
    Date of Patent: November 25, 2008
    Assignee: Geron Corporation
    Inventors: Chunhui Xu, Yan Li, Ramkumar Mandalam
  • Patent number: 7452718
    Abstract: This invention provides a new procedure for generating cardiomyocyte lineage cells from embryonic stem cells for use in regenerative medicine. Differentiating by way of embryoid body formation or in serum is no longer required. Instead, the stem cells are plated onto a solid substrate, and differentiated in the presence of select factors and morphogens. After enrichment for cells with the appropriate phenotype, the cells are allowed to cluster into cardiac bodies™, which are remarkably homogeneous and suitable for the treatment of heart disease.
    Type: Grant
    Filed: March 21, 2005
    Date of Patent: November 18, 2008
    Assignee: Geron Corporation
    Inventors: Joseph D. Gold, Mohammad Hassanipour, Lila R. Collins, Chunhui Xu
  • Patent number: 7425448
    Abstract: This invention provides populations human cells of the cardiomyocyte lineage. The cells are obtained by causing cultures of pluripotent stem cells to differentiate in vitro, and then harvesting cells with certain phenotypic features. Differentiated cells bear cell surface and morphologic markers characteristic of cardiomyocytes, and a proportion of them undergo spontaneous periodic contraction. Highly enriched populations of cardiomyocytes and their replicating precursors can be obtained, suitable for use in a variety of applications, such as drug screening and therapy for cardiac disease.
    Type: Grant
    Filed: July 12, 2002
    Date of Patent: September 16, 2008
    Assignee: Geron Corporation
    Inventor: Chunhui Xu
  • Patent number: 7413904
    Abstract: This disclosure provides a system for obtaining genetically altered primate pluripotent stem (pPS) cells. The role of the feeder cells is replaced by supporting the culture on an extracellular matrix, and culturing the cells in a conditioned medium. The cells can be genetically altered with a viral vector or DNA/lipid complex, and then selected for successful transfection by drug-resistant phenotype in the transfected cells. The system allows for bulk proliferation of genetically altered pPS cells as important products for use in human therapy or drug screening.
    Type: Grant
    Filed: September 24, 2004
    Date of Patent: August 19, 2008
    Assignee: Geron Corporation
    Inventors: Joseph D. Gold, Melissa K. Carpenter, Margaret S. Inokuma, Chunhui Xu
  • Patent number: 7410798
    Abstract: This disclosure provides an improved system for culturing human pluripotent stem cells. Traditionally, pluripotent stem cells are cultured on a layer of feeder cells (such as mouse embryonic fibroblasts) to prevent them from differentiating. In the system described here, the role of feeder cells is replaced by components added to the culture environment that support rapid proliferation without differentiation. Effective features are a suitable support structure for the cells, and an effective medium that can be added fresh to the culture without being preconditioned by another cell type. Culturing human embryonic stem cells in fresh medium according to this invention causes the cells to expand surprisingly rapidly, while retaining the ability to differentiate into cells representing all three embryonic germ layers. This new culture system allows for bulk proliferation of pPS cells for commercial production of important products for use in drug screening and human therapy.
    Type: Grant
    Filed: September 4, 2002
    Date of Patent: August 12, 2008
    Assignee: Geron Corporation
    Inventors: Ramkumar Mandalam, Chunhui Xu, Joseph D. Gold, Melissa K. Carpenter
  • Patent number: 7403718
    Abstract: Disclosed is a technique for compensating for optical passband shift of an optical component (for example an optical demultiplexer). A broadband source coupled to a dispersive element generates a chirped pulsed optical signal. Data is modulated onto particular wavelengths of the chirped pulsed optical signal by appropriately synchronizing a data modulator. The modulated signal is transmitted to the downstream optical demultiplexer, which may be subject to passband shift due to, for example, changes in environmental conditions. A feedback signal from an output port of the demultiplexer is provided to the transmitter and is used to phase shift the modulator. The phase shift results in effectively adjusting the wavelength onto which the data is modulated to substantially correspond to the passband centers of the demultiplexer.
    Type: Grant
    Filed: April 24, 2002
    Date of Patent: July 22, 2008
    Assignee: Lucent Technologies Inc.
    Inventors: Manyalibo Joseph Matthews, Chunhui Xu
  • Publication number: 20080020458
    Abstract: This disclosure provides an improved system for culturing human pluripotent stem cells. Traditionally, pluripotent stem cells are cultured on a layer of feeder cells (such as mouse embryonic fibroblasts) to prevent them from differentiating. In the system described here, the role of feeder cells is replaced by components added to the culture environment that support rapid proliferation without differentiation. Effective features are a suitable support structure for the cells, and an effective medium that can be added fresh to the culture without being preconditioned by another cell type. Culturing human embryonic stem cells in fresh medium according to this invention causes the cells to expand surprisingly rapidly, while retaining the ability to differentiate into cells representing all three embryonic germ layers. This new culture system allows for bulk proliferation of pPS cells for commercial production of important products for use in drug screening and human therapy.
    Type: Application
    Filed: September 4, 2002
    Publication date: January 24, 2008
    Inventors: Ramkumar Mandalam, Chunhui Xu, Joseph Gold, Melissa Carpenter
  • Patent number: 7297539
    Abstract: This disclosure provides an improved system for culturing human pluripotent stem cells. Traditionally, pluripotent stem cells are cultured on a layer of feeder cells (such as mouse embryonic fibroblasts) to prevent them from differentiating. In the system described here, the role of feeder cells is replaced by components added to the culture environment that support rapid proliferation without differentiation. Effective features are a suitable support structure for the cells, and an effective medium that can be added fresh to the culture without being preconditioned by another cell type. Culturing human embryonic stem cells in fresh medium according to this invention causes the cells to expand surprisingly rapidly, while retaining the ability to differentiate into cells representing all three embryonic germ layers. This new culture system allows for bulk proliferation of pPS cells for commercial production of important products for use in drug screening and human therapy.
    Type: Grant
    Filed: June 21, 2004
    Date of Patent: November 20, 2007
    Assignee: Geron Corporation
    Inventors: Ramkumar Mandalam, Chunhui Xu
  • Patent number: 7206522
    Abstract: A photomultiplier module (PMT), preferably a PMT with a gallium arsenide (GaAs) photocathode, is used as a N-photon detector (N is an integer ?2). The PMT detects the N-photon absorption rate of an optical signal having a wavelength range extending from 1.0 ?m to an upper wavelength region that increases as the number of photons simultaneously absorbed by the PMT increases beyond two. The N-photon absorption rate is used by a signal compensation apparatus to reduce impairments which affect the rate, such as group velocity dispersion and/or polarization mode dispersion, in a received optical pulse communication signal. The N-photon absorption rate can also be used to determine the optical signal-to-noise ratio of a received optical pulse communication signal, and/or to synchronize a second optical pulse signal with the first optical signal.
    Type: Grant
    Filed: April 24, 2002
    Date of Patent: April 17, 2007
    Assignee: Lucent Technologies Inc.
    Inventors: Hernando Garcia, Daniel Charles Kilper, Jeffrey Matthew Roth, Chunhui Xu
  • Patent number: 7062176
    Abstract: A nonlinear phase-shift compensation method and apparatus is provided for improving system performance in optical transmission systems. The apparatus includes a phase-shift compensating device that provides a partial compensating phase shift to reduce the nonlinear phase noise resulting from self-phase modulation and amplified spontaneous emissions in an optical transmission system.
    Type: Grant
    Filed: December 30, 2002
    Date of Patent: June 13, 2006
    Assignee: Lucent Technologies Inc.
    Inventors: Xiang Liu, Colin J McKinstrie, Linn Frederick Mollenauer, Richart Elliott Slusher, Xing Wei, Chunhui Xu
  • Patent number: 7041438
    Abstract: This disclosure provides an improved system for culturing human pluripotent stem (pPS) cells in the absence of feeder cells. The role of the feeder cells can be replaced by supporting the culture on an extracellular matrix, and culturing the cells in a conditioned medium. Permanent cell lines are provided that can produce conditioned medium on a commercial scale. Methods have also been discovered to genetically alter pPS cells by introducing the cells with a viral vector or DNA/lipid complex. The system described in this disclosure allows for bulk proliferation of pPS cells for use in studying the biology of pPS cell differentiation, and the production of important products for use in human therapy.
    Type: Grant
    Filed: October 23, 2001
    Date of Patent: May 9, 2006
    Assignee: Geron Corporation
    Inventors: Melissa K. Carpenter, Margaret S. Inokuma, Chunhui Xu
  • Patent number: 7024111
    Abstract: Apparatus and method is described for using a silicon photon-counting avalanche photodiode (APD) to detect at least two-photon absorption (TPA) of an optical signal, the optical signal having a wavelength range extending from 1.2 ?m to an upper wavelength region that increases as the number of photons simultaneously absorbed by the APD increases beyond two. In one embodiment, the TPA count is used by a signal compensation apparatus to reduce dispersion of a received optical pulse communication signal subjected to group velocity dispersion, polarization mode dispersion, or other signal impairment phenomena which effect the TPA count. Another embodiment, the TPA count is used to determine the optical signal-to-noise ratio of a received optical pulse communication signal. Another embodiment uses the TPA count to determine the autocorrelation between a first and second optical pulse signals as a function of the relative delay between the first and second optical pulse signals.
    Type: Grant
    Filed: March 16, 2002
    Date of Patent: April 4, 2006
    Assignee: Lucent Technologies Inc.
    Inventors: Wayne Harvey Knox, Jeffrey M. Roth, Chunhui Xu
  • Publication number: 20060057720
    Abstract: This invention provides populations of mesenchymal cells obtained from pluripotent stem cells by differentiating them ex vivo. Multipotent mesenchymal cells can in turn be differentiated into more specialized cell types such as osteoblasts, with properties that make them suitable for reconstituting musculoskeletal cell function in an individual. The compositions, methods, and techniques described in this disclosure can be used for a variety of commercially important diagnostic, drug screening, and therapeutic applications.
    Type: Application
    Filed: October 17, 2005
    Publication date: March 16, 2006
    Inventors: Chunhui Xu, R. Thies
  • Publication number: 20050282274
    Abstract: This invention provides populations of mesenchymal cells obtained from pluripotent stem cells by differentiating them ex vivo. Multipotent mesenchymal cells can in turn be differentiated into more specialized cell types such as osteoblasts, with properties that make them suitable for reconstituting musculoskeletal cell function in an individual. The compositions, methods, and techniques described in this disclosure can be used for a variety of commercially important diagnostic, drug screening, and therapeutic applications.
    Type: Application
    Filed: August 16, 2005
    Publication date: December 22, 2005
    Inventors: Chunhui Xu, R. Thies
  • Publication number: 20050214939
    Abstract: This invention provides a new procedure for generating cardiomyocyte lineage cells from embryonic stem cells for use in regenerative medicine. Differentiating by way of embryoid body formation or in serum is no longer required. Instead, the stem cells are plated onto a solid substrate, and differentiated in the presence of select factors and morphogens. After enrichment for cells with the appropriate phenotype, the cells are allowed to cluster into cardiac bodies™, which are remarkably homogeneous and suitable for the treatment of heart disease.
    Type: Application
    Filed: March 21, 2005
    Publication date: September 29, 2005
    Inventors: Joseph Gold, Mohammad Hassanipour, Lila Collins, Chunhui Xu
  • Publication number: 20050214938
    Abstract: This disclosure describes clusters of cardiomyocyte lineage cells referred to as cardiac bodies. They can be obtained by differentiating human embryonic stem cells into cells that express cardiomyocyte markers, and separating cells according to their density. Single suspended cells are removed, leaving self-aggregating clusters that can be propagated and enriched in further separation steps. The resulting cardiac bodies express cardiomyocyte markers at levels ˜100-fold above the starting cell population, and undergo spontaneous periodic contraction. The clusters can be used intact or dispersed into single-cell suspensions for use in research, drug screening or the preparation of pharmaceutical compositions for the treatment of cardiac disease.
    Type: Application
    Filed: March 21, 2005
    Publication date: September 29, 2005
    Inventors: Joseph Gold, Chunhui Xu