ABSTRACT
BACKGROUND:Osteogenesis is closely integrated with angiogenesis in bone formation and repair process, and hypoxia-inducible factor 1 alpha (HIF-1α) is considered to be the most important core transcription factor promoting angiogenesis gene regulation, which may promote the formation of blood vessels at hypoxia portion, and thus contribute to bone formation. OBJECTIVE:To construct the Lenti-HIF-1α-IRES-EGFP (wild type) and Lenti-HIF-1α-IRES-EGFP (point mutant type) lentiviral eukaryotic expression vectors and to detect their impact on the osteogenic gene expression of rabbit bone marrow mesenchymal stem cells. METHODS:The Lenti-HIF-1α-IRES-EGFP (wild type) and Lenti-HIF-1α-IRES-EGFP (point mutant type) lentiviral eukaryotic expression vectors were constructed according to the wild type human HIF-1αgene sequence and the determined restriction sites of human HIF-1αpoint mutant sequence. Rabbit bone marrow mesenchymal stem cells were transfected with the prepared Lenti-HIF-1α-IRES-EGFP (wild type) and Lenti-HIF-1α-IRES-EGFP (point mutant type) virus solution. RESULTS AND CONCLUSION:Immunofluorescence microscopy observations indicated that the cells of Lenti-HIF-1α-IRES-EGFP (wild type) group and Lenti-HIF-1α-IRES-EGFP (point mutant type) group showed no obvious fluorescence on transfected 7 days, and two groups of cells showed a more obvious green fluorescent after transfection 14 days. Quantitative PCR analysis results showed that there were obvious HIF-1αand bonemorphogenetic protein 2 gene expressions on days 7 after transfection and the two genes stil showed highly expression levels after transfection 14 days. The two lentiviral eukaryotic expression vectors of Lenti-HIF-1α-IRES-EGFP (wild type) and Lenti-HIF-1α-IRES-EGFP (point mutant type) could be constructed according to the wild type human HIF-1αgene sequence and the determined restriction sites of human HIF-1αpoint mutant sequence;HIF-1αgene can promote the osteogenic gene expression of lentivirus-transfected rabbit bone marrow mesenchymal stem cells.
ABSTRACT
In this paper, a new method was presented which can generate dental panoramic radiographs from the 3D CT sectional data. The dental panoramic radiograph was generated by casting ray into the 3D sectional data from a curved surface close to the dental arch. With this method, the relationship between the 3D CT sectional data and the dental panoramic radiographs was built, which helped to overcome the defects in the real X-ray panoramic radiographs, such as structure overlap and unselectable content for displaying. The technology is of certain significance in computer aided technique and surgical planning related to dentistry.