The goal of this study was to investigate isoform-specific functional domains of the inhibitory troponin subunit, troponin I (TnI), as it functions within the intact myofilaments of adult cardiac myocytes. Adenovirus-mediated gene transfer was used to deliver and express a TnI chimera composed of the amino terminus of cardiac TnI (cTnI) and the carboxy terminus of slow skeletal TnI (ssTnI) in a...

Selective troponin I (TnI) modification has been demonstrated to be in part responsible for the contractile dysfunction observed with myocardial ischemia/reperfusion injury. We have isolated and characterized modified TnI products in isolated rat hearts after 0, 15, or 60 minutes of ischemia followed by 45 minutes of reperfusion using affinity chromatography with cardiac troponin C (TnC) and an...

Troponin T (TnT), a thin filament myofibrillar protein, is essential for the Ca2+ regulation of striated muscle contraction in vertebrates, both in vivo and in vitro. To understand the role of TnT in this process, its interaction with two other troponin components, troponin I (TnI) and troponin C (TnC) was examined by using the yeast two hybrid system, which is a genetic approach to detect prot...

Troponin I (TnI) is a muscle-specific protein and plays an allosteric function in the Ca(2+) regulation of cardiac and skeletal muscle contraction. Expression of cloned cDNA in Escherichia coli is an essential approach to preparing human TnI and mutants for structural and functional studies. The expression level of cardiac TnI in E. coli is very low. To reduce the potential toxicity of cardiac ...

BACKGROUND High-sensitivity troponin I (hs-TnI) and troponin T (hs-TnT) are moderately correlated and independently related to outcome in atrial fibrillation (AF). Rate controlling therapy has been shown to reduce hs-TnT, however the potential impact on hs-TnI levels, and whether this differs from the effects on hs-TnT, has not been investigated previously. METHODS Sixty patients with stable,...

OBJECTIVE To examine the utility of point-of-care qualitative troponin I (TnI) testing in patients with possible acute coronary syndromes (ACS). METHODS A retrospective chart review of all patients undergoing qualitative TnI testing between September 2001 and February 2002 was conducted at the emergency departments of 3 rural hospitals in Alberta. We looked at the incidence of ACS, the compar...

INTRODUCTION Plasma troponin I (TnI) concentration is a well-established and widely-used marker of myocardial damage. AIM To determine the correlation between TnI concentration measured within the first 4 days following heart transplantation (HTX) and clinical course, with consideration of hemodynamic performance. MATERIAL AND METHODS The retrospective study included 54 patients (12-62 year...

OBJECTIVES Elevated concentrations of C-reactive protein (CRP), a non-specific acute phase reactant, and troponin I (TnI), a cardiac-specific marker of myocardial damage, have been found to be associated with a higher risk for cardiac events in patients with an acute coronary syndrome. We evaluated CRP alone and in combination with TnI for predicting the incidence of major cardiac complications...

BACKGROUND The relationship of routine postoperative troponin I (TnI) monitoring in kidney transplant recipients and in-hospital myocardial infarction (MI) is not known. METHODS This observational study evaluated the prevalence of abnormal postoperative TnI (Ortho Clinical Diagnostics assay) in 376 consecutive kidney or kidney/pancreas transplant recipients. In-hospital MI was adjudicated usi...

The α-helix in troponin I (TnI) at the interface with troponin T (TnT) is a highly conserved structure. A point mutation in this region, A116G, was found in human cardiac TnI in a case of cardiomyopathy. An adjacent dominantly negative mutation found in turkey cardiac TnI (R111C, equivalent to K117C in human and K118C in mouse) decreased diastolic function and blunted beta-adrenergic response i...