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Guo Li,
Xiao-Ai Zhang,
Hua Wang,
Xin Wang,
Chun-Ling Meng,
Chu-Yan Chan,
David Tai Wai Yew,
Kam Sze Tsang,
Karen Li,
Sau-na Tsai,
Sai-Ming Ngai,
Zhong Chao Han,
Marie Chia-Mi Lin,
Ming-Liang He,
Hsiang-Fu Kung
[show abstract]
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ABSTRACT: Umbilical cord (UC) and placenta (P) have been suggested as alternatives to bone marrow (BM) as sources of mesenchymal stem
cells (MSC) for cell therapy, with both UC- and P-MSC possess immunophenotypic and functional characteristics similar to BM-MSC.
However, under defined conditions, the migration capacity of BM- and P-MSC was found to be 5.9- and 3.2-folds higher than
that of UC-MSC, respectively. By the use of 2-DE and combined MS and MS/MS analysis, six differentially expressed proteins
were identified among these MSC samples, with five of them known to be involved in cell migration as migration enhancing or
inhibiting proteins. Interestingly, the expression levels of those proteins reflect perfectly the migration capacity of corresponding
MSC, which is also proved by in vitro overexpression and silencing techniques. Our study indicates that a bunch of migration-related
proteins are pivotal in governing the migration capacity of MSC.
12/2011: pages 51-68;
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Jin-fang Zhang,
Wei-ming Fu,
Ming-liang He,
Wei-dong Xie,
Qing Lv,
Gang Wan, Guo Li,
Hua Wang,
Gang Lu,
Xiang Hu,
Su Jiang,
Jian-na Li,
Marie C M Lin,
Ya-ou Zhang,
Hsiang-fu Kung
[show abstract]
[hide abstract]
ABSTRACT: Osteogenic differentiation of mesenchymal stem cells (MSCs) is a complex process, which is regulated by various factors including microRNAs. Our preliminary data showed that the expression of endogenous miR-20a was increased during the course of osteogenic differentiation. Simultaneously, the expression of osteoblast markers and regulators BMP2, BMP4, Runx2, Osx, OCN and OPN was also elevated whereas adipocyte markers PPARγ and osteoblast antagonist, Bambi and Crim1, were downregulated, thereby suggesting that miR-20a plays an important role in regulating osteoblast differentiation. To validate this hypothesis, we tested its effects on osteogenic differentiation by introducing miR-20a mimics and lentiviral-miR20a-expression vectors into hMSCs. We showed that miR-20a promoted osteogenic differentiation by the upregulation of BMP/Runx2 signaling. We performed bioinformatics analysis and predicted that PPARγ, Bambi and Crim1 would be potential targets of miR-20a. PPARγ is a negative regulator of BMP/Runx2 signaling whereas Bambi or Crim1 are antagonists of the BMP pathway. Furthermore, we confirmed that all these molecules were indeed the targets of miR-20a by luciferase reporter, quantitative RT-PCR and western blot assays. Similarly to miR-20a overexpression, the osteogenesis was enhanced by the silence of PPARγ, Bambi or Crim1 by specific siRNAs. Taken together, for the first time, we demonstrated that miR-20a promoted the osteogenesis of hMSCs in a co-regulatory pattern by targeting PPARγ, Bambi and Crim1, the negative regulators of BMP signaling.
RNA biology 09/2011; 8(5):829-38. · 5.56 Impact Factor
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[show abstract]
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ABSTRACT: This study aims to modify a cyclodextrin-PEI-based polymer, PEI-β-CyD, with the TAT peptide for plasmid DNA delivery to placenta mesenchymal stem cells (PMSCs). By using the disulfide exchange between the SPDP-activated PEI-β-CyD and TAT peptide, the TAT-PEI-β-CyD polymer was fabricated and the success of this was confirmed by the presence of characteristic peaks for PEI (at δ 2.8-3.2 ppm), CyD (at δ 5.2, 3.8-4.0 and 3.4-3.6 ppm) and TAT (at δ 1.6-1.9 and 6.8-7.2 ppm) in the (1)H NMR spectrum of TAT-PEI-β-CyD. The polymer-plasmid-DNA polyplex could condense DNA at an N/P ratio of 7.0-8.0, and form nanoparticles with the size of 150.6±5.6 nm at its optimal N/P ratio (20/1). By examining the transfection efficiency and cytotoxicity of TAT-PEI-β-CyD, conjugation of the TAT peptide onto PEI-β-CyD was demonstrated to improve the transfection efficiency of PEI-β-CyD in PMSCs after 48 and 96 hours of post-transfection incubation. The viability of PEI-β-CyD-treated PMSCs was shown to be over 80% after 5 h of treatment and 24 h of post-treatment incubation. In summary, this study showed that the TAT-PEI-β-CyD polymer as a vector for plasmid DNA delivery to PMSCs and other cells warrants further investigations. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s12668-011-0010-9) contains supplementary material, which is available to authorized users.
BioNanoScience. 09/2011; 1(3):89-96.
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Guo Li,
Xiao-Ai Zhang,
Hua Wang,
Xin Wang,
Chun-Ling Meng,
Chu-Yan Chan,
David Tai Wai Yew,
Kam Sze Tsang,
Karen Li,
Sau-Na Tsai,
Sai-Ming Ngai,
Zhong Chao Han,
Marie Chia-Mi Lin,
Ming-Liang He,
Hsiang-Fu Kung
[show abstract]
[hide abstract]
ABSTRACT: Umbilical cord (UC) and placenta (P) have been suggested as alternatives to bone marrow (BM) as sources of mesenchymal stem cells (MSC) for cell therapy, with both UC- and P-MSC possess immunophenotypic and functional characteristics similar to BM-MSC. However, under defined conditions, the migration capacity of BM- and P-MSC was found to be 5.9- and 3.2-folds higher than that of UC-MSC, respectively. By the use of 2-DE and combined MS and MS/MS analysis, six differentially expressed proteins were identified among these MSC samples, with five of them known to be involved in cell migration as migration enhancing or inhibiting proteins. Interestingly, the expression levels of those proteins reflect perfectly the migration capacity of corresponding MSC, which is also proved by in vitro overexpression and silencing techniques. Our study indicates that a bunch of migration-related proteins are pivotal in governing the migration capacity of MSC.
Advances in experimental medicine and biology 01/2011; 720:51-68. · 1.09 Impact Factor
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[show abstract]
[hide abstract]
ABSTRACT: Umbilical cord (UC) and placenta (P) are generally believed to be potential alternatives to bone marrow (BM), as sources of mesenchymal stem cells (MSC) for cell therapy. They possess immunophenotypic and functional characteristics which are similar to that of BM-MSC, yet one of the crucial factors in determining the tissue regeneration process--the migration capacity--is still unclear. In our previous study, the migration capacity of BM- and P-MSC was found 5.9- and 3.2-fold higher than that of UC-MSC, respectively. By using 2-dimensional gel electrophoresis (2-DE) and combined MS and MS/MS analysis, six proteins were identified as differentially expressed among these MSC samples. Five out of the six proteins were known to be involved in cell migration as migration inhibiting or enhancing proteins.
Methods in molecular biology (Clifton, N.J.) 01/2011; 698:443-57.
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[show abstract]
[hide abstract]
ABSTRACT: Umbilical cord (UC) and placenta (P) are generally believed to be potential alternatives to bone marrow (BM), as sources of
mesenchymal stem cells (MSC) for cell therapy. They possess immunophenotypic and functional characteristics which are similar
to that of BM-MSC, yet one of the crucial factors in determining the tissue regeneration process – the migration capacity
– is still unclear. In our previous study, the migration capacity of BM- and P-MSC was found 5.9- and 3.2-fold higher than
that of UC-MSC, respectively. By using 2-dimensional gel electrophoresis (2-DE) and combined MS and MS/MS analysis, six proteins
were identified as differentially expressed among these MSC samples. Five out of the six proteins were known to be involved
in cell migration as migration inhibiting or enhancing proteins.
Key wordsMesenchymal stem cells-Migration-2-Dimensional gel electrophoresis-MS and MS/MS analysis
12/2010: pages 443-457;
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ABSTRACT: Spontaneous intracerebral hemorrhage (ICH) carries a high mortality rate, with survivors commonly left with permanent neurological deficits. Mesenchymal stem cell (MSC) transplantation promotes functional recovery in experimental ICH, and treatment with hepatocyte growth factor (HGF) is beneficial in ischemic stroke.
We hypothesize that transplantation of MSCs with previous transduction of HGF has an additive effect in promoting neurological recovery through myelin and axonal regeneration.
HGF transduction to human umbilical cord-derived MSCs using lentiviral plasmid pWPI-HGF-GFP was prepared. One week after a collagenase-induced ICH, 80 male Sprague-Dawley rats were divided into 3 groups for stereotactic injection of phosphate-buffered saline (group I), MSC transplant (group II), and HGF-transduced MSC transplant (group III), respectively, into the left ventricle. The animals were assessed weekly for 5 weeks using the Rotarod motor function test, at which time they were killed for Luxol fast blue myelin staining and appropriate immunohistochemistry and Western blotting.
Animals receiving transplanted HGF-transduced MSCs (group III) exhibited significantly better motor function recovery than animals treated with MSCs alone (group II), which in turn performed better than the phosphate-buffered saline controls at 2 weeks after transplantation. Luxol fast blue staining of myelin displayed significantly less demyelination and significantly higher reactivity in myelin basic protein and growth-associated protein-43 in immunohistochemistry and Western blotting and significantly reduced myelin-associated glycoprotein activity in group III animals.
Animals transplanted with HGF-transduced MSCs 1 week after experimental ICH were shown to achieve a better neurological recovery. This improved neurological recovery from ICH is attributed to nerve fiber remyelination and axonal regeneration.
Neurosurgery 08/2010; 67(2):357-65; discussion 365-6. · 2.79 Impact Factor
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ABSTRACT: Fructus Ligustri Lucidi (FLL) has been used in traditional Chinese medicine for over 1000 years. The ethanol extract of FLL (EFLL) has been shown to be a potential candidate in the prevention and treatment of osteoporosis. The present study aimed to determine whether EFLL carries out the effect by promoting osteogenesis in mesenchymal stem cells (MSCs). The osteogenic differentiation of MSCs was evaluated by their alkaline phosphatase (ALP) activities and mineralization. Expression of genes was detected by RT-PCR. We found that EFLL significantly stimulated the ALP activities and shortened the time needed for the mineralization of MSCs during osteogenic differentiation. The expression of several osteoblast differentiation regulators was also upregulated by EFLL during this process. Our study demonstrated that the EFLL is capable of enhancing osteogenic differentiation of MSCs. It might be useful for treating diseases with inadequate bone formation, including osteoporosis.
Phytotherapy Research 10/2009; 24(4):571-6. · 2.09 Impact Factor
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ABSTRACT: Herba Epimedii is one of the most commonly used Chinese herbs for treating osteoporosis. In the present study, the flavonoids of Herba Epimedii (HEF) have shown to promote the osteogenic differentiation of human bone marrow-derived mesenchymal stem cells. They were noted to enhance the mRNA expression of BMP-2, BMP-4, Runx2, beta-catenin and cyclinD1, all of which are BMP or Wnt-signaling pathway related regulators. The osteogenic effect was inhibited by the introduction of noggin and DKK-1, which is classical inhibitor of BMP and Wnt/beta-catenin signaling, respectively. These results suggest that HEF exerts promoting effect on osteogenic differentiation, which plausibly functions via the BMP and Wnt/beta-catenin signaling pathways. Considering the therapeutic efficiency and economical issues, HEF may be a potential candidate for promoting bone regeneration. On the other hand, osteogenic differentiation of MSCs may also be a promising and attractive tool to apply in bone repair.
Molecular and Cellular Endocrinology 09/2009; 314(1):70-4. · 4.19 Impact Factor
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ABSTRACT: In China Herba Epimedii is one of the most common herbs that could be prescribed for treating osteoporosis. It is known to increase the overall mineral content, therefore, to promote bone formation and to increase lumbar bone mineral density (BMD). The present study was aimed at investigating the effect of flavonoids of Herba Epimedii (HEF) on osteogenesis in human MSCs.
The human bone marrow-derived MSCs (BM-MSCs) were isolated and their osteogenic differentiation was evaluated by their alkaline phosphatase (ALP) activities and level of mineralization. After treating with total flavonoids during osteogenic differentiation process, differential mRNA expression was examined by RT-PCR.
The total time needed for osteogenic differentiation of BM-MSCs was significantly shortened by adding HEF. Up-regulation of mRNA expression by HEF was observed for several marker genes and osteogenic regulators. HEF was also found to inhibit osteoclastogenesis of MSCs by enhancing the ratio OPG/RANKL.
Our study demonstrated that the HEF could improve osteogenic differentiation and inhibit the osteoclast differentiation of BM-MSCs concurrently.
Phytomedicine: international journal of phytotherapy and phytopharmacology 05/2009; 16(6-7):521-9. · 2.17 Impact Factor
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Hongping Xia,
Yanting Qi,
Samuel S Ng,
Xiaona Chen,
Dan Li,
Shen Chen,
Ruiguang Ge,
Songshan Jiang, Guo Li,
Yangchao Chen,
Ming-Liang He,
Hsiang-fu Kung,
Lihui Lai,
Marie C Lin
[show abstract]
[hide abstract]
ABSTRACT: MicroRNAs (miRNAs) are a class of endogenous, small non-protein coding single-stranded RNA molecules, which are crucial post-transcriptional regulators of gene expression. Previous studies have shown that miRNAs participate in a wide range of biological functions and play important roles in various human diseases including glioma. However, the role of miRNAs in mediating glioblastoma cell migration and invasion has not been elucidated. Using miRNA microarray, we identified miR-146b as one of the miRNAs that is significantly dysregulated in human glioblastoma tissue. We showed that miR-146b overexpression by transfection with the precursor miR-146b, or knock-down by Locked Nucleic Acid (LNA)-modified anti-miR-146b, has no effect on the growth of human glioblastoma U373 cells. However, precursor miR-146b transfection significantly reduced the migration and invasion of U373 cells, while LNA-anti-miR-146b transfection generated the opposite result. Furthermore, we discovered that a matrix metalloproteinase gene, MMP16, is one of the downstream targets of miR-146b. Taken together, our findings suggest that miR-146b is involved in glioma cell migration and invasion by targeting MMPs, and implicate miR-146b as a metastasis-inhibiting miRNA in glioma.
Brain research 04/2009; 1269:158-65. · 2.46 Impact Factor
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Guo Li,
Xiao-ai Zhang,
Hua Wang,
Xin Wang,
Chun-ling Meng,
Chu-yan Chan,
David Tai Wai Yew,
Kam Sze Tsang,
Karen Li,
Sau-na Tsai,
Sai-ming Ngai,
Zhong Chao Han,
Marie Chia-mi Lin,
Ming-liang He,
Hsiang-fu Kung
[show abstract]
[hide abstract]
ABSTRACT: Umbilical cord (UC) and placenta (P) have been suggested as alternatives to bone marrow (BM) as sources of mesenchymal stem cells (MSC) for cell therapy, with both UC- and P-MSC possess immunophenotypic and functional characteristics similar to BM-MSC. However, their migration capacity, which is indispensable during tissue regeneration process, is unclear. Under defined conditions, the migration capacity of BM- and P-MSC was found 5.9- and 3.2-folds higher than that of UC-MSC, respectively. By the use of 2-DE and combined MS and MS/MS analysis, six differentially expressed proteins were identified among these MSC samples, with five of them known to be involved in cell migration as migration enhancing or inhibiting proteins. Consistent with their migration capacity, the levels of migration enhancing proteins including cathepsin B, cathepsin D and prohibitin,were significantly lower in UC-MSC when compared with those in BM- and P-MSC. For the migration inhibiting proteins such as plasminogen activator inhibitor-1 (PAI-1) and manganese superoxide dismutase, higher expression was found in the UC-MSC. We also showed that the overexpression of the PAI-1 impaired the migration capacity of BM- and P-MSC while silencing of PAI-1 enhanced the migration capacity of UC-MSC. Our study indicates that PAI-1 and other migration-related proteins are pivotal in governing the migration capacity of MSC.
Proteomics 02/2009; 9(1):20-30. · 4.43 Impact Factor
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Hongping Xia,
Yanting Qi,
Samuel S Ng,
Xiaona Chen,
Shen Chen,
Marong Fang,
Dan Li,
Yu Zhao,
Ruiguang Ge, Guo Li,
Yangchao Chen,
Ming-Liang He,
Hsiang-fu Kung,
Lihui Lai,
Marie C Lin
[show abstract]
[hide abstract]
ABSTRACT: MicroRNAs (miRNAs) are non-protein-coding RNAs that function as post-transcriptional gene regulators. Recent evidence has shown that miRNA plays a pivotal role in the development of many cancers including glioma, a lethal brain cancer. We have recently compared the miRNA expression profiles between normal brain and glioma tissues from Chinese patients by miRNA microarray and identified a panel of differentially expressed miRNAs. Here, we studied the function of one miRNA, miR-15b, in glioma carcinogenesis and elucidated its downstream targets. Over-expression of miR-15b resulted in cell cycle arrest at G0/G1 phase while suppression of miR-15b expression resulted in a decrease of cell populations in G0/G1 and a corresponding increase of cell populations in S phase. We further showed that CCNE1 (encoding cyclin E1) is one of the downstream targets of miR-15b. Taken together, our findings indicate that miR-15b regulates cell cycle progression in glioma cells by targeting cell cycle-related molecules.
Biochemical and Biophysical Research Communications 02/2009; 380(2):205-10. · 2.48 Impact Factor
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ABSTRACT: The precise segmentation of magnetic resonance images (MRI) is an important subject in both medical and computer science communities. The intrinsic complexity of the images and their relative lack of systematics have brought to develop different approaches to segment the different parts of human head. This paper investigates a novel feature extraction approach to MRI segmentation based on feed-back pulse coupled neural network in conjunction with toboggan theory. Due to the dynamics of the FPCNN, multiple unconnected groups of neurons will often pulse at the same time, calling for further processing to identify distinct regions. We locate the object's label by FPCNN. Finally, toboggan automatically partitions the MRI image. The experimental results show that the proposed algorithm performs well compared to the traditional algorithms.
Industrial Electronics and Applications, 2007. ICIEA 2007. 2nd IEEE Conference on; 06/2007
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ABSTRACT: Toboggan is an important tool on image segmentation, and the performance of image segmentation based on toboggan mostly independent on the gradient image. A method of image segmentation was presented, which is toboggan segmentation. The gradient image is computed by using the multi-scale morphological gradient operation. The approach of region merging is used after toboggan segmentation. Region merging was carried out according to region area and region homogeneity. It was proved that the method was valid and more accurate than other common algorithms of image segmentation.
Industrial Electronics and Applications, 2007. ICIEA 2007. 2nd IEEE Conference on; 06/2007
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ABSTRACT: A novel pilot-assistant DOA estimation algorithm is presented based on the Butler matrix. The orthogonal channel code is used to avoid the correlation between the desired signal and the interference. The algorithm is combined of a rough estimation stage and an accurate estimation stage which are mostly fulfilled by hardware. It approaches the DOA of the desired signal iteratively through the variable phase shifter. And the accuracy of the algorithm can be decided by users. The merits of its low-complexity and quick convergence make it suitable to be used in ad-hoc network terminals. Simulation results verified the algorithm.
Communications and Networking in China, 2006. ChinaCom '06. First International Conference on; 11/2006
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ABSTRACT: A new version of Montgomery's algorithm or modular multiplication of large integers is presented in this paper. And a 64-bit parallel carry look-ahead binary adder implemented by SRCMOS (self-resetting CMOS) circuits substitutes for the CPA and one of the two CSAs, which are needed in the previous implementation. And then we can get the modular multiplication result after the loop without the final comparison achieved by making the size of r two nits larger than that of N. In addition, SRCMOS circuits have lower power, faster switching speed and less area than equivalent static CMOS implementations, so we can get a high performance RSA cryptosystem.
ASIC, 2003. Proceedings. 5th International Conference on; 11/2003
