Publications by authors named "Bai Ci"

2 Publications

  • Page 1 of 1

[Cardiomyocyte-like differentiation of human bone marrow mesenchymal stem cells after exposure of 5-azacytidine in vitro].

Shi Yan Sheng Wu Xue Bao 2004 Apr;37(2):118-24

Beijing Institute of Transfusion medicine, Beijing 100850, China.

To investigate the potential of adult mesenchymal stem cells (hMSCs) derived from human bone marrow to undergo cardiomyogenic differentiation after exposure of 5-azacytidine in vitro. A small bone marrow aspirate was taken from the iliac crest of human volunteers, and hMSCs were isolated by 1.073 g/mL Percoll and cultured in the right cell culturing medium as previously described. The phonotypes of hMSCs were identified by flow cytometry. The stem cells were cultured in cell culture medium (as control) and medium mixed with 5-azacytidine (5-aza, 3, 5, 10 micromol/L) (n=5, respectively) for cellular differentiation. We examined respectively with immunohischemistry at 21 days of inducement on desmin, cardiac-specific cardiac troponin I (cTnI), GATA4 & connexin43. The ultrastructures of induced cells were examined by transmission electron microscope. The results indicated that the hMSCs showed a fibroblast-like morphology with vortex distribution in their peak propagation, and express high level of CD44 but negative for CD34 and CD45. 20%-30% cells grown after 5, 10 microl/L 5-aza treatment connected with adjoining cells and coalesced into myotube structures after 14 days. After 21 days of culturing, immunohistochemistry revealed expression of desmin, GATA4, cTnI and connexin43 in 5, 10 micromol/L showed positive, but no cardiac specific protein were found in neither 3 micromol/L nor in control group. The ratio of cTnI positive stained cells in 10 micromol/L group were higher than that in 5 micromol/L group (65.3+/-4.7% vs 48.2+/-5.4%, p<0.05). Electron microscopy revealed myofilaments were formed. The results indicated that purified hMSCs from adult bone marrow can be differentiated into cardiac-like muscle cells with 5-aza inducement in vitro and the differentiation is in line with the 5-aza concentration.
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April 2004

[Effects of gap in primitive subalpine fir forest on diversity of herb and shrub in Tibet].

Ying Yong Sheng Tai Xue Bao 2004 Feb;15(2):191-4

Tibet Agriculture and Animal Husbandry College, Li'nzhi 860000, China.

Effects of gap in primitive fir forest in southeast Tibet on species diversity of herb and shrub were studied. The results showed that species composition, distribution and diversity in gap were different from those in non-gap. The improvement of illumination and other habitat conditions resulted in richer species of herb and shrub in gap. There were shade-tolerant and photophilic herb species and shrub species in gap, however, only shade-tolerant herb species and shrub species grew in non-gap. Species diversity and evenness in gap were higher than in non-gap. The diminutive similar coefficient between herb and shrub communities showed that certain difference existed between herb and shrub communities in stands of gap and non-gap. The similar coefficients were little correlative between gap area and communities. Gap was important to improve growth of herb and shrub and maintain species diversity of primitive subalpine fir forest in southwest Tibet.
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February 2004