Cardiomyocytes rely on proper mitochondrial homeostasis to maintain contractility and achieve optimal cardiac performance. Mitochondrial homeostasis is controlled by mitochondrial fission, fusion, and mitochondrial autophagy (mitophagy). Mitophagy plays a particularly important role in promoting the degradation of dysfunctional mitochondria in terminally differentiated cells.
View Article and Find Full Text PDFThe serine/threonine kinase, PINK1, and the E3 ubiquitin ligase, Parkin, are known to facilitate LC3-dependent autophagosomal encasement and lysosomal clearance of dysfunctional mitochondria, and defects in this process contribute to a variety of cardiometabolic and neurological diseases. Although recent evidence indicates that dynamic actin remodeling plays an important role in PINK1/Parkin-mediated mitochondrial autophagy (mitophagy), the underlying signaling mechanisms remain unknown. Here, we identify the RhoGAP GRAF1 (Arhgap26) as a PINK1 substrate that regulates mitophagy.
View Article and Find Full Text PDFDevelopmentally programmed polyploidy (whole-genome duplication) of cardiomyocytes is common across evolution. Functions of such polyploidy are essentially unknown. Here, in both Drosophila larvae and human organ donors, we reveal distinct polyploidy levels in cardiac organ chambers.
View Article and Find Full Text PDFBackground: Reliable biomarkers for assessing the viability of the donor hearts undergoing perfusion remain elusive. A unique feature of normothermic perfusion on the TransMedics® Organ Care System (OCS™) is that the donor heart is maintained in a beating state throughout the preservation period. We applied a video algorithm for an assessment of cardiac kinematics, video kinematic evaluation (Vi.
View Article and Find Full Text PDFPurpose/objectives: Multimedia presentations and online platforms are used in dental education. Though studies indicate the benefits of video-based lectures (VBLs), data regarding user reception and optimal video features in dental education are limited, particularly on Web 2.0 platforms like YouTube.
View Article and Find Full Text PDFTransplantation, the gold standard intervention for organ failure, is a clinical field that is ripe for applications of gene therapy. One of the major challenges in applying gene therapy to this field is the need for a method that achieves consistent and robust gene delivery to allografts. Normothermic perfusion is a growing organ preservation method and a device for cardiac preservation was recently approved by the Food and Drug Administration (FDA) (Organ Care System, OCS™; TransMedics, Inc.
View Article and Find Full Text PDFDevelopmentally programmed polyploidy (whole-genome-duplication) of cardiomyocytes is common across evolution. Functions of such polyploidy are essentially unknown. Here, we reveal roles for precise polyploidy levels in cardiac tissue.
View Article and Find Full Text PDFThe porcine intra-abdominal heterotopic heart transplantation model allows for the assessment of immunologic effects on cardiac transplantation without relying on the allograft to maintain hemodynamic support for the animal. Historically, allograft function and histology is monitored by physical exam, echocardiogram evaluation, percutaneous core biopsy, and open biopsy. We performed transvenous endomyocardial biopsies in three pigs that had undergone heterotopic heart implantation.
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