Julian Borejdo

Summary

Affiliation: University of North Texas
Country: USA

Publications

  1. ncbi request reprint Rotation of actin monomers during isometric contraction of skeletal muscle
    Julian Borejdo
    University of North Texas Health Science Center, Department of Molecular Biology and Immunology, Fort Worth, Texas 76107, USA
    J Biomed Opt 12:014013. 2007
  2. doi request reprint Single molecule detection approach to muscle study: kinetics of a single cross-bridge during contraction of muscle
    Julian Borejdo
    Department of Molecular Biology and Immunology, Center for Commercialization of Fluorescence Technologies, University of North Texas Health Science Center, Fort Worth, TX, USA
    Methods Mol Biol 875:311-34. 2012
  3. ncbi request reprint E22K mutation of RLC that causes familial hypertrophic cardiomyopathy in heterozygous mouse myocardium: effect on cross-bridge kinetics
    D Dumka
    Univ of North Texas Health Science Center, Fort Worth, TX 76107, USA
    Am J Physiol Heart Circ Physiol 291:H2098-106. 2006
  4. doi request reprint Reduction of photobleaching and photodamage in single molecule detection: observing single actin monomer in skeletal myofibrils
    Julian Borejdo
    University of North Texas Health Science Center, Department of Molecular Biology and Immunology, Fort Worth, Texas 76107, USA
    J Biomed Opt 13:034021. 2008
  5. ncbi request reprint Rotations of a few cross-bridges in muscle by confocal total internal reflection microscopy
    J Borejdo
    Department of Molecular Biology and Immunology, the University of North Texas HSC, Fort Worth, TX 76107, USA
    Biochim Biophys Acta 1763:137-40. 2006
  6. ncbi request reprint Measuring rotations of a few cross-bridges in skeletal muscle
    Julian Borejdo
    Department of Molecular Biology and Immunology, University of North Texas, Fort Worth, TX 76107, USA
    Exp Biol Med (Maywood) 231:28-38. 2006
  7. pmc Rotation of the lever arm of Myosin in contracting skeletal muscle fiber measured by two-photon anisotropy
    J Borejdo
    Department of Molecular Biology and Immunology, University of North Texas, Fort Worth, Texas 76107, USA
    Biophys J 87:3912-21. 2004
  8. pmc Changes in orientation of actin during contraction of muscle
    J Borejdo
    Department of Molecular Biology and Immunology, University of North Texas, Fort Worth, Texas, USA
    Biophys J 86:2308-17. 2004
  9. pmc Orientational changes of crossbridges during single turnover of ATP
    J Borejdo
    Department of Molecular Biology and Immunology, University of North Texas, Fort Worth, Texas 76107 2699, USA
    Biophys J 84:2450-9. 2003
  10. pmc Regulatory and essential light chains of myosin rotate equally during contraction of skeletal muscle
    Julian Borejdo
    Department of Molecular Biology and Immunology, University of North Texas, Fort Worth, Texas 76107 2699, USA
    Biophys J 82:3150-9. 2002

Research Grants

Collaborators

Detail Information

Publications28

  1. ncbi request reprint Rotation of actin monomers during isometric contraction of skeletal muscle
    Julian Borejdo
    University of North Texas Health Science Center, Department of Molecular Biology and Immunology, Fort Worth, Texas 76107, USA
    J Biomed Opt 12:014013. 2007
    ..The root mean-squared anisotropy fluctuations are greater in isometrically contracting than in rigor myofibrils. The results support the view that during isometric contraction, cross-bridges undergo a mechanical cycle...
  2. doi request reprint Single molecule detection approach to muscle study: kinetics of a single cross-bridge during contraction of muscle
    Julian Borejdo
    Department of Molecular Biology and Immunology, Center for Commercialization of Fluorescence Technologies, University of North Texas Health Science Center, Fort Worth, TX, USA
    Methods Mol Biol 875:311-34. 2012
    ..5 and 5.8 s, respectively. These findings suggest that alterations in myosin cross-bridge kinetics associated with D166V mutation of RLC ultimately affect the ability of a heart to efficiently pump the blood...
  3. ncbi request reprint E22K mutation of RLC that causes familial hypertrophic cardiomyopathy in heterozygous mouse myocardium: effect on cross-bridge kinetics
    D Dumka
    Univ of North Texas Health Science Center, Fort Worth, TX 76107, USA
    Am J Physiol Heart Circ Physiol 291:H2098-106. 2006
    ..The slight increase in tau(1) was probably caused by myofibrillar disarray. The decrease in tau(2) of Tg hearts was probably caused by replacement of the mouse RLC for the human isoform in the Tg mice...
  4. doi request reprint Reduction of photobleaching and photodamage in single molecule detection: observing single actin monomer in skeletal myofibrils
    Julian Borejdo
    University of North Texas Health Science Center, Department of Molecular Biology and Immunology, Fort Worth, Texas 76107, USA
    J Biomed Opt 13:034021. 2008
    ..They decrease damage to cells because they enhance the electric field near the fluorophore, making it possible to illuminate samples with weaker light...
  5. ncbi request reprint Rotations of a few cross-bridges in muscle by confocal total internal reflection microscopy
    J Borejdo
    Department of Molecular Biology and Immunology, the University of North Texas HSC, Fort Worth, TX 76107, USA
    Biochim Biophys Acta 1763:137-40. 2006
    ..Myosin heads rotated at a rate approximately equal to the ATPase rate, suggesting that bulk ATPase of a whole muscle reflects the cycle frequency of individual heads...
  6. ncbi request reprint Measuring rotations of a few cross-bridges in skeletal muscle
    Julian Borejdo
    Department of Molecular Biology and Immunology, University of North Texas, Fort Worth, TX 76107, USA
    Exp Biol Med (Maywood) 231:28-38. 2006
    ..The S/N ratio was sufficiently large to make statistically significant comparisons from rigor and contracting myofibrils...
  7. pmc Rotation of the lever arm of Myosin in contracting skeletal muscle fiber measured by two-photon anisotropy
    J Borejdo
    Department of Molecular Biology and Immunology, University of North Texas, Fort Worth, Texas 76107, USA
    Biophys J 87:3912-21. 2004
    ..The results indicated that the power stroke begins approximately 170 ms after the rigor cross-bridge first binds ATP...
  8. pmc Changes in orientation of actin during contraction of muscle
    J Borejdo
    Department of Molecular Biology and Immunology, University of North Texas, Fort Worth, Texas, USA
    Biophys J 86:2308-17. 2004
    ..These results suggest that orientation changes of actin are caused by dissociation and rebinding of myosin cross-bridges, and that during contraction, nucleotide does not dissociate from actin...
  9. pmc Orientational changes of crossbridges during single turnover of ATP
    J Borejdo
    Department of Molecular Biology and Immunology, University of North Texas, Fort Worth, Texas 76107 2699, USA
    Biophys J 84:2450-9. 2003
    ..A model was constructed that quantified this effect. After accounting for the slowdown, the halftimes of dissociation and attachment were 34 and 200 ms, respectively...
  10. pmc Regulatory and essential light chains of myosin rotate equally during contraction of skeletal muscle
    Julian Borejdo
    Department of Molecular Biology and Immunology, University of North Texas, Fort Worth, Texas 76107 2699, USA
    Biophys J 82:3150-9. 2002
    ..These results suggest that the interactions of LC1 do not inhibit the angular motion of the proximal end of the regulatory domain and that the whole domain rotates as a rigid body...
  11. pmc Comparison of orientation and rotational motion of skeletal muscle cross-bridges containing phosphorylated and dephosphorylated myosin regulatory light chain
    Krishna Midde
    Department of Cell Biology and Anatomy, University of North Texas, Health Science Center, Fort Worth, Texas 76107, USA
    J Biol Chem 288:7012-23. 2013
    ..A simple theory was developed to account for this fact...
  12. pmc Kinetics of a single cross-bridge in familial hypertrophic cardiomyopathy heart muscle measured by reverse Kretschmann fluorescence
    Prasad Mettikolla
    University of North Texas Health Science Center, Department of Molecular Biology and Immunology, Fort Worth, Texas 76107, USA
    J Biomed Opt 15:017011. 2010
    ..These results are consistent with the fact that mutated heart muscle myosin translates actin faster in in vitro motility assays...
  13. doi request reprint Metal-enhanced immunoassays
    Ignacy Gryczynski
    Center for Commercialization of Fluorescence Technologies, University of North Texas Health Science Center, Fort Worth, TX, USA
    Methods Mol Biol 875:217-29. 2012
    ..The SACS surfaces show extraordinary fluorescence enhancements: over 100-folds in hot spots. We applied these surfaces for enhanced Alexa488 model immunoassay...
  14. doi request reprint Molecular fluorescence enhancement on fractal-like structures
    Rafal Luchowski
    Center for Commercialization of Fluorescence Technologies, UNTHSC, Fort Worth, Texas 76107, USA
    Appl Spectrosc 64:578-83. 2010
    ..We therefore believe that silver fractal-like nanostructures can be used successfully in ultrasensitive assays and fluorophore trace detection...
  15. pmc Elimination of autofluorescence in fluorescence correlation spectroscopy using the AzaDiOxaTriAngulenium (ADOTA) fluorophore in combination with time-correlated single-photon counting (TCSPC)
    Ryan M Rich
    Department of Molecular Biology and Immunology, Center for Commercialization of Fluorescence Technologies, University of North Texas Health Science Center, Fort Worth, TX 76107, USA
    Anal Bioanal Chem 405:4887-94. 2013
    ..We then show that both time gating and FLCS may be used successfully with ADOTA-labeled HA to detect the presence of hyaluronidase, the overexpression of which has been observed in many types of cancer...
  16. doi request reprint Polarized fluorescent nanospheres
    Rafal Luchowski
    Department of Molecular Biology and Immunology, University of North Texas Health Science Center, Center for Commercialization of Fluorescence Technologies, 3500 Camp Bowie Boulevard, TX, Fort Worth, 76107, USA
    Opt Express 18:4289-99. 2010
    ..A progressive decrease of absorption was observed. Next, photophysical properties of photobleached and not bleached films dissolved in water were compared...
  17. pmc Fluorescence instrument response standards in two-photon time-resolved spectroscopy
    Rafal Luchowski
    Center for Commercialization of Fluorescence Technologies, Dept of Molecular Biology and Immunology, UNTHSC, Fort Worth, Texas 76107, USA
    Appl Spectrosc 64:918-22. 2010
    ..We believe that picosecond lifetime standards for two-photon excitation will find broad applications in multiphoton spectroscopy and in fluorescence lifetime imaging microscopy (FLIM)...
  18. pmc Single actomyosin motor interactions in skeletal muscle
    Zeno Földes-Papp
    Department of Molecular Biology and Immunology, University of North Texas Health Science Center, 3500 Camp Bowie Boulevard, Fort Worth, TX 76107, USA
    Biochim Biophys Acta 1813:858-66. 2011
    ..Clusters of polarized photons indicated an anisotropy decay of single actomyosin motors of ~9s during muscle contraction. This article is part of a Special Issue entitled: 11th European Symposium on Calcium...
  19. doi request reprint Decreasing photobleaching by silver nanoparticles on metal surfaces: application to muscle myofibrils
    Priya Muthu
    University of North Texas Health Science Center, Department of Molecular Biology and Immunology, Center for Commercialization of Fluorescent Technology, Fort Worth, Texas 76107, USA
    J Biomed Opt 13:014023. 2008
    ....
  20. pmc Detection of hyaluronidase activity using fluorescein labeled hyaluronic acid and Fluorescence Correlation Spectroscopy
    Ryan M Rich
    Department of Molecular Biology and Immunology, Center for Commercialization of Fluorescence Technologies, University of North Texas Health Science Center, Fort Worth, TX 76107, USA
    J Photochem Photobiol B 116:7-12. 2012
    ..The method we present provides a sensitive measure of hyaluronidase activity and requires extremely small amounts of the HA substrate...
  21. pmc Elimination of autofluorescence background from fluorescence tissue images by use of time-gated detection and the AzaDiOxaTriAngulenium (ADOTA) fluorophore
    Ryan M Rich
    Department of Molecular Biology and Immunology, Center for Commercialization of Fluorescence Technologies, University of North Texas Health Science Center, Fort Worth, TX 76107, USA
    Anal Bioanal Chem 405:2065-75. 2013
    ..This time-gating eliminates over 96 % of autofluorescence. Analysis using a variable time-gate may enable quantitative determination of the bound probe without the contributions from the background...
  22. ncbi request reprint Fluorescence polarization standard for near infrared spectroscopy and microscopy
    Rafal Luchowski
    Center for Commercialization of Fluorescence Technologies CCFT, Department of Molecular Biology and Immunology, University of North Texas Health Science Center, Fort Worth, TX 76107, USA
    Appl Opt 47:6257-65. 2008
    ....
  23. pmc Single molecule studies of multiple-fluorophore labeled antibodies. Effect of homo-FRET on the number of photons available before photobleaching
    Rafal Luchowski
    Center for Commercialization of Fluorescence Technologies, Department of Cell Biology and Genetics, University of North Texas Health Science Center, Fort Worth, TX 76106, USA
    Curr Pharm Biotechnol 9:411-20. 2008
    ..Extending the observation time will be crucial for developing immunoassays based on single-antibody...
  24. pmc Lifetime-based sensing of the hyaluronidase using fluorescein labeled hyaluronic acid
    Rafal Fudala
    Department of Molecular Biology and Immunology, Center for Commercialization of Fluorescence Technologies, University of North Texas Health Science Center, Fort Worth, TX 76107, USA
    J Photochem Photobiol B 106:69-73. 2012
    ..We demonstrate that the calibration of the sensing response is the same for the average lifetime as for a single exponential decay approximation, which significantly simplifies the analysis of the sensing measurements...
  25. pmc Fluorescence detection of MMP-9. I. MMP-9 selectively cleaves Lys-Gly-Pro-Arg-Ser-Leu-Ser-Gly-Lys peptide
    Rafal Fudala
    Center of Commercialization of Fluorescence Technologies, Department of Molecular Biology and Immunology, UNTHSC, Fort Worth, TX 76107, USA
    Curr Pharm Biotechnol 12:834-8. 2011
    ..The control MMP-2 enzyme does not cause any changes in either 5-FAM or Cy5 fluorescence. We believe that our observation will help in early detection of elevated MMP-9 levels under disease conditions...
  26. doi request reprint Instrument response standard in time-resolved fluorescence
    Rafal Luchowski
    Department of Molecular Biology and Immunology, Center for Commercialization of Fluorescence Technologies, UNTHSC, Fort Worth, Texas 76107, USA
    Rev Sci Instrum 80:033109. 2009
    ..We demonstrate that the fluorescence decay of LDS 798 is a better approximation of IRF, in particular, for avalanche photodiodes used in the near infrared spectral region...
  27. pmc Imaging exocytosis of ATP-containing vesicles with TIRF microscopy in lung epithelial A549 cells
    Irina Akopova
    Center for Commercialization of Fluorescence Technologies, Department of Molecular Biology and Immunology, University of North Texas, Fort Worth, TX, USA
    Purinergic Signal 8:59-70. 2012
    ..Collectively, our data demonstrate that regulated exocytosis of ATP-loaded vesicles likely constitutes a major pathway of hypotonic stress-induced ATP secretion from A549 cells...
  28. ncbi request reprint In situ single-molecule imaging with attoliter detection using objective total internal reflection confocal microscopy
    Thomas P Burghardt
    Department of Physiology and Biomedical Imaging, Mayo Clinic, Rochester, Minnesota 55905, USA
    Biochemistry 45:4058-68. 2006
    ..Muscle tissue contains myosin at a approximately 120 microM concentration. Evidence is provided that >75% of the bleachable fluorescence detected with fTIRM is emitted by five chromophore-labeled myosins in a muscle fiber...

Research Grants9

  1. IMAGING MELANIN IN MELANOCYTES
    Julian Borejdo; Fiscal Year: 2003
    ..The modifications are relatively simple, inexpensive and not tied to a specific brand of instrument. It is expected that the method will find application in a small diagnostic laboratory. ..
  2. Improved Confocal Microscope: Detection & Functionality
    Julian Borejdo; Fiscal Year: 2005
    ..To facilitate a future commercialization, a microscope maintenance/modification company that is interested in distribution of the product version of the modification package has been identified. ..
  3. Rotation of Single Cross-Bridge in Skeletal Muscle Fiber
    Julian Borejdo; Fiscal Year: 2007
    ..This is expected to provide definitive answers about the mechanism of contraction of skeletal muscle. ..
  4. Single Cross-Bridge Kinetics in Transgenic Mouse Hearts Expressing FHC Mutations
    Danuta Szczesna Cordary; Fiscal Year: 2010
    ....