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The relevant policies of national essential medicine system were reviewed, major concerns and actions in the implementation of essential medicine system in Shanghai were introduced, and the suggestions to improve the implementation of essential medicine system of Shanghai were made. These provided the information for policy making and provided a useful experience for facilitating the establishment of essential medicine system and the improvement of its implementation in Shanghai as well as China.
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BACKGROUND: Umbilical cord blood-derived mesenchymal stem cells (UCB-MSCs) have been shown to lead to new tissue formation after homing and engrafting to the heart. But the safety of UCB-MSCs engrafting remains to be further investigated. OBJECTIVE: To study the safety and apoptosis inhibition of the UCB-MSCs under co-culture conditions on human cardiomyocytes. METHODS: UCB was collected at delivery with informed consent obtained from 10 donors. The UCB-MSCs were treated with 5-azaserine to induce differentiation into cardiomyocytes. The in vitro cultured cells of the 3rd-5~(th) passages and dividing cells were taken to detect telomerase activity, tumor-related gene expression, G-banding patterns of chromosomal karyotupes, cell surface antigen expression, tumor formation in nude mice, and inhibited apoptosis under co-culture conditions. RESULTS AND CONCLUSION: Prior to and after 5-azaserine induction, telomerase activity and tumor-related gene expression (p53, cyclin A, cdk2, β-actin, C-fos, h-TERT, c-myc) of UCB-MSCs were similar, no abnormal chromosomal karyotupes were observed, immunophenotype exhibited no change, CD34 was negative, but CD44 and CD90 (Thy-1) were positive. At 10 weeks after inoculation of UCB-MSCs, nude mice still survived healthily and no formed tumor in vivo was observed. Hematoxylin-eosin staining suggested normal subcutaneous tissue. Compared with simple cardiomyocytes, UCB-MSCs could significantly inhibit cardiomyocyte apoptosis under co-culture conditions (P < 0.05), indicating that human UCB-MSCs are a valuable, safe, and effective source of cell transplantation treatment.
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Objective To study the safety and effect of the umbilical cord blood(UCB)-derived mesenchymal stem cells(MSCs)on apoptosis of human cardiomyocytes(HCM). MethodsUCB was collected at the time of delivery with informed consent obtained from 10donors.The UCB-derived MSCs were treated with 5-azaserube(5-AZA)and were further induced to differentiate into cardiomyocytes.Telomerase activity,G-banding patterns of chromosomal karyotypes,tumor formation in nude mice,RT-PCR,and the effect of inhibiting apoptosis of HCM were investigated. ResultsMSCs derived from UCB were differentiated into cardiomyocytes in vitro,which possessed telomerase activity after 5-AZA induction,and no abnormal chromosomal karyotypes were observed.Expression of p53,cyclin A,cdk2,β-actin,C-fos,h-TERT and c-myc were similar in MSCs before and after 5-AZA treatment.There was no tumor formation in nude mice after injection of UCB-derived MSCs.UCB-derived MSCs significantly inhibited apoptosis of HCM. ConclusionUCB-derived MSCs are a valuable,safe and effective source of cell-transplantation treatment.
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BACKGROUND:Compared with the bone marrow mesenchymal stem cells (BMSCs),cells from the umbilical cord blood (UCB)are considered"very young",and its proliferation and differentiation cannot decrease with age.Thus,cells from UCB are a great substitute of BMSCs.OBJECTIVE:To observe the characteristics of in vitro differentiation of UCB-MSCs into cardiomyocytes.DESIGN,TIME AND SETTING:The observational experiment was performed at the Beijing Sijitan Hospital from March 2005 to February 2007.MATERIALS:Cells from UCB were collected from healthy arturients after signing the informed consent.METHODS:Mononuclear cells were isolated to further harvest MSCs.At the third passage,CD34,CD44 and CD90 were measured using immunofluorescence flow cytometry.After 4 weeks of 5-azacitidine treatment,myosin heavy chain,GATA4 and troponin 1 were identified using immunohistochemistry and reverse transcription-polymerase chain reaction.MAIN OUTCOME MEASURES:β-myosin heavy chain,GATA4 and troponin I expression.RESULTS:UCB-MSCs showed a fibrolast-like morphology,clonally expanded after 5-azacitidine reatment.The immunophenotype of these clonally expanded cells is consistent with that reported for BMSCs.Immunohistochemistry and reverse transcription-polymerase chain reaction showed β-myosin heavy chain,GATA4 and troponin I expression.CONCLUSION:UCB-MSCs differentiate into cardiomyocyte-like cells,which have the characteristics of cardiomyocytes.