Objective To investigate the effect of combined delivery of hepatocyte growth factor (HGF) and insulinlike growth factor-1 (IGF-1) on the development of bone mesenchymal stem cells (BMSCs) differentiation by expression of GATA-4，and to supply some evidence for clinical BMSCs transplantation therapy. Methods BMSCs were isolated from the femurs and tibias of the randomly assigned rabbits and cocultured with myocytes in a ratio of 1∶1. Myocytes were obtained from neonatal rabbits ventricles. 150 ng/ml HGF and 200 ng/ml IGF-1 were added into 4 culture bottles of 8 bottles and the other 4 bottles were not. After BMSCs were cocultured with myocytes for 1 day, 3 days, 1 week, and till 6 weeks， differentiated BMSCs were targeted and microdissected with a laser capture microdissection system, and then ribonucleic acid (RNA) was extracted and isolated. The differentiation of BMSCs in coculture was confirmed by immunohistochemistry, electron microscopy, and reverse transcriptionpolymerase chain reaction (RT-PCR). And expression of GATA-4 in BMSCs was detected by semiquantitative RT-PCR. Results Before coculturing, the BMSCs were negative for α-actinin and exhibited a nucleus with many nucleoli. After coculture with myocytes, some BMSCs became αactininpositive and showed a cardiomyocytelike ultrastructure, including sarcomeres, endoplasmic reticulum, and mitochondria. BMSCs cocultured with myocytes expressed cardiac transcription factor GATA-4. IGF-1 and HGF delivery can significantly increased expression of GATA-4 for the differentiated BMSCs as compared with cells of no delivery of HGF and IGF-1. The expression level of GATA-4 in captured BMSCs began to increase at the 1st day, reach the peak at the 2nd week and kept high expression level after the 2nd week. Conclusion BMSCs can transdifferentiate into cells with a cardiac phenotype when cocultured with myocytes. Differentiated myocytes express cardiac transcription factors GATA-4. Administration of HGF and IGF-1 promoted the development of BMSCs transdifferentiate into cardiac phenotype, which is associated with the increase in expression level of GATA-4.
Objective To compare the clinical outcomes and safety of minimally invasive and routine mitral valve repair or replacement for patients with single mitral valve disease. Methods We retrospectively analyzed the clinical data of 67 patients with single mitral valve disease （without aortic valve and tricuspid valve lesion or other heart diseases including atrial septal defect） who underwent mitral valve repair or replacement in the First Affiliated Hospital of China Medical University between January and July 2011. The patients were divided into two groups according to different surgical approaches：the minimally invasive surgery group （n=29，8 males and 21 females，age 51.4±9.4 years） underwent minimally invasive mitral valve repair or replacement via right mini-thoractomy；and the routine surgery group （n=38，11 males and 27 females，age 53.6±11.9 years） underwent mitral valve repair or replacement via middle sternotomy. In the minimally invasive surgery group，9 patients underwent mitral valve repair while the other 20 patients underwent mitral valve replacement. And no patient underwent transition to routine operation. In the routine surgery group，15 patients underwent mitral valve repair and 23 patients underwent mitral valve replacement. Clinical outcomes and safety of the operations were compared between the two groups. Results There was no statistical difference in operation time between the two groups （207.9±18.1 min versus 198.4±27.5 min，P=0.076）. The amount of postoperative drainage （126.7±34.5 ml versus 435.6±87.2 ml，P=0.000） and blood transfusion （red blood cell 1.4±0.8 U versus 2.3±1.1 U，P=0.000；blood plasma 164.3±50.4 ml versus 405.6±68.9 ml，P=0.000） of the minimally invasive surgery group were significantly lower than those of the routine surgery group. The cardiopulmonary bypass time （81.7±23.9 min versus 58.7±13.6 min，P=0.000） and aortic-clamping time （51.6±12.7 min versus 38.4±11.7 min，P=0.000） of the minimally invasive surgery group were significantly longer than those of the routine surgery group. The length of ICU stay （22.5±3.6 h versus 31.7±8.5 h，P=0.000），mechanical ventilation （7.4±3.2 h versus 11.2±5.1 h，P=0.000） and postoperative hospitalization （7.1±1.6 d versus 13.5±2.4 d，P=0.000） of the minimally invasive surgery group were significantly shorter than those of the routine surgery group. There was no statistical difference in postoperative complications between the two groups. Minimally invasive surgery group patients were followed up for 5.3±2.4 months with a follow-up rate of 72.4%（21/29）. Routine surgery group patients were followed up for 5.5±3.8 months with a follow-up rate of 71.0%（27/38）. There was no significant complication during follow-up in both two groups. Conclusion Minimally invasive mitral valve operation via right mini-thoracotomy is effective and safe with a good cosmetic result. Compared with routine operation，patients undergoing minimally invasive operation recover better and faster.