The curative effect of the associated cell transplantation on the rabbit myocardial infarction

Inducing Mesenchymal stem cells to differentiate into cardiomyocycte-like cells and endothelial progenitor cells orientedly and evaluating the curative effect of the associated cell transplantation on the rabbit myocardial infarction (MI). Methods: Mesenchymal stem cells (MSCs) were isolated from the bone marrow of 24 rabbits and cultured in special cell culture medium containing 5-azacytidine (5-AZA), endothelial cell growth supplements (ECGS), vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (BFGF) respectively. The cell transplantation was performed 2 weeks after MI. Rabbits were divided into control group, cardiomyocytes-like cell group, endothelial progenitor cell group and combination group. We used the echocardiography to measure the heart function 2 to 4 weeks after MI, TTC to measure the area of the infarction, flow cytometry to estimate the cell apoptosis. Results: After induced, MSCs were differentiated orientedly into cardiomyocycte-like cells (CLCs) and endothelial progenitor cells (EPCs). CLCs became greater and had a “stick” or “ball” shape. Transmisson electron microscopy showed that the cells had oval nuclei positioned in the central part and well organized myofilaments, atrial granules and mitochomdrion. RT-PCR showed the expression of the atrial natriuretic polypeptide, phospholamban and myosin heavy chain in CLCs. EPCs formed confluent one-celled layer which showed a cobblestone shape by phase-contrast microscope. The expression of CD133 in EPCs was much at first and then descended gradually. Compared with the control group, cell transplantation could improve the heart function, reduce the size of MI, decrease the left ventricular end systole diameter and end diastolic diameter, suppressed cell apoptosis. The curative effect of cell transplantation was better in the associated-cell group than in the single-cell transplantation group (LVEF: 32.49% ± 1.29% vs 53.22% ± 2.13% vs 56.91% ± 2.04% vs 62.61% ± 2.37%, P < 0.05;LVESD: 1.23 ± 0.02 vs 0.98 ± 0.04 vs 0.98 ± 0.12 vs 1.11 ± 0.03, P < 0.05;LVEDD: 1.53 ± 0.13 vs 1.24 ± 0.02 vs 1.21 ± 0.09 vs 1.01 ± 0.01, P .98% vs 28.61% ± 1.24% vs 29.73% ± 2.11% vs 22.82% ± 3.12%, P < 0.05;apotosis: 8.6% ± 0.94% vs 6.94% ± 0.59% vs 6.4% ± 0.27% vs 4.63% ± 0.74%, P clusions: This study showed that MSCs can differentiate into CLCs and EPCs in the given conditions and the associated cell transplantation is better than the single cell transplantation to treat MI.

Ethylenediaminetetraacetic acid-assisted synthesis of Bi2Se3 nanostructures with unique edge sites

Nanomaterials with unique edge sites have received increasing attention due to their superior performance in various applications. Herein, we employed an effective ethylenediaminetetraacetic acid (EDTA)-assisted method to synthesize a series of exotic Bi2Se3nanostructures with distinct edge sites. It was found that the products changed from smooth nanoplates to half-plate-containing and crown-like nanoplates upon increasing the molar ratio of EDTA to Bi3+. Mechanistic studies indicated that, when a dislocation source and relatively high supersaturation exist, the step edges in the initially formed seeds can serve as supporting sites for the growth of epilayers, leading to the formation of half-plate-containing nanoplates. In contrast, when the dislocation source and a suitably low supersaturation are simultaneously present in the system, the dislocation-driven growth mode dominates the process, in which the step edges form at the later stage of the growth responsible for the formation of crown-like nanoplates. [Figure not available: see fulltext.] © 2016, Tsinghua University Press and Springer-Verlag Berlin Heidelberg.