Biomedical subjects

Shuhua Yang

Publications and source records attributed to Shuhua Yang.

23 records · Page 2Linked to original sources

PubMed2003

Construction of antisense transforming growth factor beta 1 gene and its effect on the proliferation by expression in osteosarcoma cells.

To construct the antisense transforming growth factor beta 1 (TGF beta 1) gene and investigate the effect of TGF beta 1 autocrine loop blockage on the proliferation of osteosarcoma cells. TGF beta 1 cDNA was cloned by RT-PCR from human osteosarcoma cells (MG-63) and inserted into pcDNA3 to construct an antisense expression vector, which was dubbed pcDNA3-TGF beta 1(-). MTT was used to detect the proliferation of osteosarcoma cells transfected by antisense TGF beta 1 gene. Our results showed that the proliferation of the transfected osteosarcoma cells was suppressed markedly. It is concluded that TGF beta 1 autocrine loop blockage in osteosarcoma cells could inhibit cell proliferation, which might be helpful for gene therapy of osteosarcoma.

Antisense Elements (Genetics)↗

PubMed2003

Vascular endothelial growth factor gene transfection to enhance the repair of avascular necrosis of the femoral head of rabbit.

OBJECTIVE: To explore a new method for the therapy of avascular necrosis of the femoral head. METHODS: The recombinant plasmid pCD-hVEGF165 was mixed with collagen and was implanted in the necrotic femoral head. The expression of vascular endothelial growth factor (VEGF) was examined by RNA dot hybridization and immunohistochemical techniques. Repair of the femoral head was observed by histological and histomorphometric analysis. RESULTS: The expression of VEGF was detected in the femoral head transfected with the VEGF gene. The femoral head transfected with the VEGF gene showed a significant increase in angiogenesis 2 and 4 weeks after gene transfection and a significant increase in bone formation 6 and 8 weeks after gene transfection on histomorphometric analysis (P < 0.01). CONCLUSIONS: Transfection of the VEGF gene enhances bone tissue angiogenesis. Repair of osteonecrosis could be accelerated accordingly, thus providing a potential method for therapy of osteonecrosis.

Animals↗

PubMed2002

Construction and expression of recombinant plasmid pCD-rbFGF in osteoblasts.

To construct basic fibroblast growth factor (bFGF) eukaryotic expression vector and to evaluate the possibility of bFGF gene therapy in orthopedic disease, the pCD-rbFGF recombinant plasmid was constructed by cloning rat basic fibroblast growth factor (bFGF) cDNA into an eukaryotic expression vector, pcDNA3. Rat osteoblasts were transfected with pCD-rbFGF plasmid by lopofectin mediated gene transfer, the transient expression was detected by streptavidin-biotin-enzyme complex (SABC) method. It was observed that the expression of rat bFGF gene was detected 72 h after transfected distinctly. Basic fibroblast growth factor gene therapy is a method of potential for a wide array of orthopedic diseases.

Animals↗

PubMed2002

Expression of transforming growth factor beta 1 in mesenchymal stem cells: potential utility in molecular tissue engineering for osteochondral repair.

The feasibility of using gene therapy to treat full-thickness articular cartilage defects was investigated with respect to the transfection and expression of exogenous transforming growth factor (TGF)-beta 1 genes in bone marrow-derived mesenchymal stem cells (MSCs) in vitro. The full-length rat TGF-beta 1 cDNA was transfected to MSCs mediated by lipofectamine and then selected with G418, a synthetic neomycin analog. The transient and stable expression of TGF-beta 1 by MSCs was detected by using immunohistochemical staining. The lipofectamine-mediated gene therapy efficiently transfected MSCs in vitro with the TGF-beta 1 gene causing a marked up-regulation in TGF-beta 1 expression as compared with the vector-transfected control groups, and the increased expression persisted for at least 4 weeks after selected with G418. It was suggested that bone marrow-derived MSCs were susceptible to in vitro lipofectamine mediated TGF-beta 1 gene transfer and that transgene expression persisted for at least 4 weeks. Having successfully combined the existing techniques of tissue engineering with the novel possibilities offered by modern gene transfer technology, an innovative concept, i.e. molecular tissue engineering, are put forward for the first time. As a new branch of tissue engineering, it represents both a new area and an important trend in research. Using this technique, we have a new powerful tool with which: (1) to modify the functional biology of articular tissue repair along defined pathways of growth and differentiation and (2) to affect a better repair of full-thickness articular cartilage defects that occur as a result of injury and osteoarthritis.

Animals↗

PubMed2002

Enhancement of endotoxin activity by muramyldipeptide.

Synthetic muramyldipeptide (MDP), the minimum structural moiety of bacterial peptidoglycan for adjuvant and related activities, sensitized mice for two types of lethal shock induced by lipopolysaccharide (LPS): an early anaphylactoid shock and late endotoxin shock. In relation to the late reaction in MDP-primed mice, enhanced production of inflammatory cytokines was induced in response to various bacterial components. MDP showed a priming effect in mice not only when administered parentally but also via the oral route. MDP activated human monocytic THP-1 cells in a CD14-, Toll-like receptor 2 (TLR2)- and TLR4-independent manner to increase expression of MyD88, a common adaptor and signaling molecule for TLRs, and exhibited synergistic cytokine inducing effects with TLR4 agonists (LPS, synthetic lipid A), TLR2 agonist (synthetic lipopeptide), and TLR9 agonist (bacterial CpGDNA) in THP-1 cells in culture. Consistent with these findings, MDP primed TLR2 knockout mice as well as wild-type controls, but not TLR4-mutated C3H/HeJ mice, to enhance production of tumor necrosis factor-alpha upon stimulation with synthetic lipid A. In contrast to the BCG- and Propionibacterium acnes-priming system, MDP primed mice in an interferon-gamma-independent manner. Further studies are required to elucidate the mechanisms of the synthetic and priming activities of MDP for various bacterial components.

Acetylmuramyl-Alanyl-Isoglutamine↗