Jonathan Kirk

Faculty Mentor: Sanjeev Shroff

Update: 

Post-doctoral work (Dr. David Kass' laboratory at the Johns Hopkins University):Dyssynchronous contraction of the left ventricle in dilated heart failure significantly worsens mortality. Cardiac Resynchronization Therapy (CRT) not only restores synchrony and systolic function, but also prolongs survival; which drug therapy does not. There is evidence that the improvement in cardiac performance is not merely from mechanical resynchronization, but also due to changes at the myofilament level. Using dog and mouse models of dyssynchronous heart failure and CRT, Dr. Kirk is studying the properties of the cardiac myofilament (skinned trabeculae and myocytes). Changes in myofilament function can be due to altered protein posttranslational modifications (PTMs, such as phosphorylation), so I am also performing 2D-DiGE experiments with mass spectrometry to identify altered protein PTMs.

Publications:

• MacGowan GA, Kirk JA, Evans C, Shroff SG. "Pressure-calcium relationships in perfused mouse hearts". Am J Physiol Heart Circ Physiol290(2614-2624): , 2006 
• Naghshin J, McGaffin K, Mathier MA, Romano LC, Smith SH, Janczewski AM, Kirk JA, Shroff SG, O'Donnell CP. "Chronic intermittent hypoxia increases left ventricular contractility in C57BL/6J mice". J Appl Physiol107(787-793): , 2009  
• Kirk JA, MacGowan GA, Evans C, Smith SH, Stewart AFR, Solaro RJ, Shroff SG. "Left ventricular and myocardial function in mice expressing constitutively psuedo-phosphorylated cardiac troponin I". Circ Res105(1232-1239): , 2009  
• Clause KC, Tinney JP, Liu LJ, Gharaibeh B, Huard J, Kirk JA, Shroff SG, Fujimoto KL, Wagner WR, Ralphe JC, Keller BB, Tobita K. "A three-dimensional gel bioreactor for assessment of cardiomyocyte induction in skeletal muscle derived stem cells". Tissue Eng Part C Methods2010( ): , 2010  
• Kirk JA, Saccomani MP, Shroff SG. "Testing global identifiability of models of sarcomere function". Am J Physiol2010( ): , 2010  
• Kirk JA, Smith SH, MacGowan GA, Shroff, SG. "Protein kinase C-induced troponin I phosphorylation causes changes in cardiac contractile function but not the intracellular calcium transient". Circulation118(II): , 2008  
• Ralphe JC, Witt M, Kirk JA, Clause KM, Keller BB, Tobita K. "Engineered neonatal rat cardiac tissue models immature in-vivo myocardium". Circulation118(II): , 2008  

Conferences:

• Annual BMES Society Meeting, Chicago, IL, United States of America, 10/2006  
• Annual BMES Meeting, Los Angeles, CA, United States of America, 09/2007  
• Annual AHA Meeting, Orlando, FL, United States of America, 11/2007  
• Center for Simulation and Modeling Poster Session, Pittsburgh, PA, United States of America, 10/2008  
• AHA Scientific Sessions, New Orleans, LA, United States of America, 11/2008  
• AHA Fellows Research Day, Pittsburgh, PA, United States of America, 02/2009  
• Biophysics Society Annual Meeting, San Francisco, CA, United States of America, 02/2010