Refractory ventricular tachycardia (VT) can be a potentially life-threatening rhythm in the presence of non-ischemic dilated cardiomyopathy, particularly when it results in hemodynamic compromise. A 65-year-old man with non-ischemic cardiomyopathy was referred for multiple episodes of VT. A HeartMate left ventricular assist device (LVAD) was implanted to stabilize and control the VT. However, he had multiple episodes of VT and the frequency of ventricular arrhythmias did not improve after LVAD implantation. He required electrical cardioversion to treat each episode. On Day 41 post-operatively, radiofrequency ablation was performed. Two significant areas of scarring were identified and were successfully ablated. After ablation, he did not have significant sustained VT episodes and was discharged.
[Show abstract][Hide abstract] ABSTRACT: Recreating ancestral proteins in the laboratory increasingly is being used to study the evolutionary history of protein function. More efficient gene synthesis techniques and the decreasing costs of commercial oligosynthesis are making this approach both simpler and less expensive to perform. Developments in ancestral reconstruction methods, particularly more realistic likelihood models of molecular evolution, allow for the accurate reconstruction of more ancient proteins than previously possible. This chapter reviews phylogenetic methods of ancestral inference, strategies for investigating alternative reconstructions, gene synthesis, and design, and an application of these methods to the reconstruction of an ancestor in the green fluorescent protein family.
Methods in Enzymology 02/2005; 395:652-70. DOI:10.1016/S0076-6879(05)95034-9 · 2.09 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The fruit fly Drosophila melanogaster, a widely utilized genetic model, is highly resistant to oxygen starvation and is beginning to be used for studying physiological, developmental, and cellular adaptations to hypoxia. The Drosophila respiratory (tracheal) system has features in common with the mammalian circulatory system so that an angiogenesis-like response occurs upon exposure of Drosophila larvae to hypoxia. A hypoxia-responsive system homologous to mammalian hypoxia-inducible factor (HIF) has been described in the fruit fly, where Fatiga is a Drosophila oxygen-dependent HIF prolyl hydroxylase, and the basic helix-loop-helix Per/ARNT/Sim (bHLH-PAS) proteins Sima and Tango are, respectively, the Drosophila homologues of mammalian HIF-alpha (alpha) and HIF-beta (beta). Tango is constitutively expressed regardless of oxygen tension and, like in mammalian cells, Sima is controlled at the level of protein degradation and subcellular localization. Sima is critically required for development in hypoxia, but, unlike mammalian model systems, it is dispensable for development in normoxia. In contrast, fatiga mutant alleles are all lethal; however, strikingly, viability to adulthood is restored in fatiga sima double mutants, although these double mutants are not entirely normal, suggesting that Fatiga has Sima-independent functions in fly development. Studies in cell culture and in vivo have revealed that Sima is activated by the insulin receptor (InR) and target-of-rapamycin (TOR) pathways. Paradoxically, Sima is a negative regulator of growth. This suggests that Sima is engaged in a negative feedback loop that limits growth upon stimulation of InR/TOR pathways.
Methods in Enzymology 02/2007; 435:123-44. DOI:10.1016/S0076-6879(07)35007-6 · 2.09 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: We report the first case of percutaneous radio-frequency (RF) ablation procedure in a patient implanted with a HeartMate II left ventricular assist device for refractory heart failure. This procedure was performed for poorly tolerated recurrent atrial arrhythmias. No harmful consequence happened during or after the procedure despite the potential electromagnetic interferences existing between the RF delivery and the functioning of the device.
Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.