Browsing by Author "Karunakaran, J"

Now showing 1 - 12 of 12
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    A large left ventricular pseudoaneurysm
    (EUROPEAN JOURNAL OF CARDIO-THORACIC SURGERY, 2016) Radhakrishnan, BK; Kumar, CJA; Philipose, S; Karunakaran, J
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    Anomalous Origin of the Left Coronary Artery From the Pulmonary Artery in an Infant and Adult: Intraoperative Echocardiographic Comparison
    (JOURNAL OF CARDIOTHORACIC AND VASCULAR ANESTHESIA, 2016) Chigurupati, K; Gadhinglajkar, S; Sreedhar, R; Karunakaran, J; Dharan, BS
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    Are nitric oxide-mediated protein modifications of functional significance in diabetic heart? ye'S, -NO', wh'Y-NO't?
    (NITRIC OXIDE-BIOLOGY AND CHEMISTRY, 2014) Jayakumari, NR; Reghuvaran, AC; Rajendran, RS; Pillai, VV; Karunakaran, J; Sreelatha, HV; Gopala, S
    Protein modifications effected by nitric oxide (NO) primarily in conjunction with reactive oxygen species (ROS) include tyrosine nitration, cysteine S-nitrosylation, and glutathionylation. The physiological and pathological relevance of these three modifications is determined by the amino acids on which these modifications occur cysteine and tyrosine, for instance, ranging from altering structural integrity/catalytic activity of proteins or by altering propensity towards protein degradation. Even though tyrosine nitration is a well-established nitroxidative stress marker, instilled as a footprint of oxygen- and nitrogen-derived oxidants, newer data suggest its wider role in embryonic heart development and substantiate the need to focus on elucidating the underlying mechanisms of reversibility and specificity of tyrosine nitration. S-nitrosylation is a covalent modification in specific cysteine residues of proteins and is suggested as one of the ways in which NO contributes to its ubiquitous signalling. Several sensitive and specific techniques including biotin switch assay and mass spectrometry based analysis make it possible to identify a large number of these modified proteins, and provide a great deal of potential S-nitrosylation sites. The number of studies that have documented nitrated proteins in diabetic heart is relatively much less compared to what has been published in the normal physiology and other cardiac pathologies. Nevertheless, elucidation of nitrated proteome of diabetic heart has revealed the presence of many mitochondrial and cytosolic proteins of functional importance. But, the existence of different models of diabetes and analyses at diverse stages of this disease have impeded scientists from gaining insights that would be essential to understand the cardiac complications during diabetes. This review summarizes NO mediated protein modifications documented in normal and abnormal heart physiology including diabetes. (c) 2014 Elsevier Inc. All rights reserved.
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    Calcific aorta and coronary artery: two cases of calcific ascending aorta and descending aorta
    (JOURNAL OF GERIATRIC CARDIOLOGY, 2015) Idhrees, AM; Radhakrishnan, BK; Panicker, VT; Pillai, V; Karunakaran, J
    Calcific aorta is a disease of old age and is an independent risk factor for morbidity and mortality. Here, we present two patients with calcific aorta at different levels. One with a descending porcelain aorta, and modified Bentall's procedure was done. Second is a patient who is having a calcific ascending aorta and coronary artery. Coronary artery bypass grafting from left internal mammary artery to left anterior descending was done for the patient. The calcification and its morbidity had been discussed briefly.
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    Differential response of human cardiac stem cells and bone marrow mesenchymal stem cells to hypoxia-reoxygenation injury
    (MOLECULAR AND CELLULAR BIOCHEMISTRY, 2017) RajendranNair, DS; Karunakaran, J; Nair, RR
    Cardiosphere-derived cells (CDCs) and bone marrow mesenchymal stem cells (MSCs) are popularly used in stem cell therapy for myocardial regeneration. The cell type that survives and maintains stem cell characteristics in the adverse microenvironment following ischemia-reperfusion injury is presumed to be ideal for transplantation. The study was therefore aimed at identifying the cell type with relatively greater resistance to ischemia-reperfusion injury. CDCs were isolated from the right atrial appendage and MSCs from bone marrow of patients who underwent coronary artery bypass graft surgery. Ischemia-reperfusion injury was simulated in vitro by subjecting the cells to hypoxia (0.5% O-2) followed by reintroduction of oxygen (HR injury). Greater resistance of CDCs to HR injury was apparent from the decreased expression of senescence markers and lower proportion of apoptotic cells (one-sixth of that in MSCs). HR injury retarded cell cycle progression in MSCs. Consequent to HR injury, cell migration and secretion of stromal-derived growth factor were stimulated, significantly in CDCs. The differentiation to myocyte lineage and angiogenesis assessed by tube formation ability was better for CDCs. Release of vascular endothelial growth factor was relatively more in CDCs and was further stimulated by HR injury. Differentiation to osteogenic and angiogenic lineage was stimulated by HR injury in MSCs. Compared to MSCs, CDCs appear to be the cell of choice for promoting myocardial regeneration by virtue of its survival capacity in the event of ischemic insult along with higher proliferation rate, migration efficiency, release of growth factors with paracrine effects and differentiation to cardiac lineage.
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    Intraoperative Identification of Chyle Leak During Coarctation Repair Using Fluorescein Dye
    (ANNALS OF THORACIC SURGERY, 2015) Mathew, T; Idhrees, M; Misra, S; Menon, S; Dharan, BS; Karunakaran, J
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    Is there any change in free flow of pedicled left internal thoracic artery conduit at varying degrees of clockwise twist up to 360 degrees?
    (JOURNAL OF THORACIC AND CARDIOVASCULAR SURGERY, 2005)
    Twisting of the aorta-coronary venous conduits is an extremely uncommon occurrence and has been reported by Roberts and colleagues' with fatal outcome. There is a reported case of a twisted pedicled left internal thoracic artery (LITA) graft as well in which the patient survived, and the follow-up coronary angiogram revealed a patent LITA with good distal runoff.(2) However, there are no published data in the English-language literature (PubMed, MEDLINE) regarding measurement of free flow from a pedicled LITA conduit in different degrees of twist. Therefore, to determine its significance on free flow, we studied the effect of varying degrees of clockwise twist of the LITA up to 360°.
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    Primary Modified Bentall's Procedure in a Case of Laubry-Pezzi Syndrome
    (ANNALS OF THORACIC SURGERY, 2014) Radhakrishnan, BK; Idhrees, AM; Devarajan, S; Panicker, VT; Pillai, VV; Varma, PK; Karunakaran, J
    Modified Bentall's procedure done as part of the primary repair in Laubry-Pezzi syndrome is very rarely described in the literature. We present a case of a 33-year-old man with a subpulmonic venticular septal defect, aneurysmal dilatation of the aortic root and ascending aorta, with an associated patent ductus arteriosus, corrected by the incorporation of Yacoub's techique for ventricular septal defect closure with a modified Bentall's procedure and transpulmonary patent ductus arteriosus ligation. The postoperative course was unremarkable. Early follow-up reports show good biventricular function without residual ventricular septal defect or iatrogenic ventricular outflow tract obstructions. (C) 2014 by The Society of Thoracic Surgeons
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    Severe hypothyroidism after coronary artery bypass grafting
    (ANNALS OF THORACIC SURGERY, 2005)
    A 56-year-old man with unstable angina underwent urgent coronary artery bypass grafting. The patient required reintubation and prolonged ventilation because of persistent drowsiness and hypotension. The patient was weaned off the ventilator and extubated; however, he remained drowsy and lethargic. Neurologic examination, electroencephalogram, and computed tomography scan of the brain did not show any organic cause of his depressed neurologic status. His metabolic profile revealed severe hypothyroidism. The patient responded well to oral thyroxine. We report the unusual manner in which hypothyroidism presented in the patient. A high index of suspicion is required to diagnose and treat this complication.
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    Sternotomy After Classic Blalock-Taussig Shunt: A Unique Challenge
    (ANNALS OF THORACIC SURGERY, 2014) Chandrasekaran, A; Mathew, T; Menon, S; Dharan, BS; Karunakaran, J; Kapilamoorthy, TR
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    Surgery for Congenital Tricuspid Valve Cleft: Tricuspid Valve Repair with Neochordae and Annuloplasty
    (JOURNAL OF HEART VALVE DISEASE, 2015) Veerbhadran, SP; Piliai, VV; Sasidharan, B; Karunakaran, J
    Background and aim of the study: Congenital abnormalities of the tricuspid valve (TV), including dysplasia, straddling, and those associated with other congenital heart disease, are rare causes of tricuspid regurgitation (TR). In congenital TV anomalies there can be varying levels of abnormalities of leaflet and subvalvular structures. Herein is reported a case of TV cleft with absent chordae, and a technique of TV repair. Methods: A 14-year-old boy was found to have severe TR due to dysplasia of the anterior TV leaflet. Intraoperatively he was noted to have dysplasia of the TV with a cleft in the anterior leaflet of the TV and an absence of chordae supporting the anterior two-thirds of the anterior leaflet. The anterior papillary muscle was hypoplastic, with chordae to the posterior leaflet and small chordae partly to the anterior leaflet. The cleft was repaired and a neochordae placed onto the anterior leaflet with attachment to the papillary muscle, followed by an annuloplasty. Results: Intraop erative and postoperative echocardiographic assessment showed good mobility of the anterior tricuspid leaflet at six months and two-year follow up. Conclusion: Chordal replacement is a useful technique for repairing congenital dysplastic TV with absent chordae. The same technique for mitral valve repair with neochordae can be applied to chordal anomalies of the TV, with excellent outcome.
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