Early steps for cardiac specification are problematic for the study of mammalian embryos, which has favored using pluripotent cells that recapitulate cardiac myogenesis. Furthermore, circuits governing cardiac specification have relevance to the application of ES cells and other cells for heart repair. In mouse teratocarcinoma cells, canonical Wnts that inhibit heart formation in avian or amphibian embryos and explants activate cardiogenesis, paradoxically. Here, we show that the Wnt/␤-catenin pathway also is essential for cardiac myogenesis to occur in ES cells, acting at a gastrulation-like stage, mediating mesoderm formation and patterning (two prerequisites for cardiac myogenesis itself). Among genes associated temporally with this step was Sox17, encoding an endodermal HMG-box transcription factor. Using lentiviral vectors for RNA interference in differentiating ES cells, an essential role for Sox17 was proven in cardiac muscle cell formation. Sox17 shorthairpin RNA suppresses cardiac myogenesis selectively, acting subsequent to mesoderm formation yet before induction of Mesp1 and Mesp2, a pair of related basic helix-loop-helix transcription factors that together are indispensable for creating heart mesoderm. Sox17 short-hairpin RNA blocks cardiac myogenesis non-cell autonomously and impairs the induction of Hex, a homeodomain transcription factor that is known to be required for the production of endoderm-derived heart-inducing factors.cardiac myogenesis ͉ differentiation ͉ ␤-catenin ͉ heart ͉ Wnt

A renal vein aneurysm is a rare vascular disease. To our knowledge, only six cases have been reported. We describe a 57-year-old woman with a left renal vein aneurysm diagnosed by a combination of ultrasonography, color Doppler ultrasonography, contrast-enhanced computed tomography, and magnetic resonance imaging.

When these abnormal enhancements of the liver on CT are recognized within the liver, these findings indicate diversion of contrast material into collateral pathways to the liver with SVC obstruction.

We report a case of recurrent malignant fibrous histiocytoma (MFH) in the left atrium, treated by removal of the tumor and the right half of the left atrium, which was reconstructed with two equine pericardial patches. Postoperative echocardiography showed patent right pulmonary veins and a properly shaped left atrium. The patient survived for 3 years after the operation with no cardiac symptoms.

We encountered an informative case of infected aortic arch aneurysm. The proximal descending aorta, left common carotid artery, and left subclavian artery were severely involved in an abscess; thus, typical in situ reconstruction of the arch was considered impossible. Therefore, to secure more distal branches appropriate for anastomosis, a modified extra-anatomic arch repair was performed through additional incisions. The patient developed renal and respiratory failure and died of septicemia five and a half months after the operation. However, postoperative computed tomograms demonstrated that the abscess had disappeared.