ABSTRACT
BACKGROUND: Bone morphogenetic protein 2 and transforming growth factor β are important factors in bone regeneration, increasing the expressions of bone morphogenetic protein 2 and transforming growth factor β can promote the osteogenic differentiation of bone marrow mesenchymal stem cells. OBJECTIVE: To construct the lentivirus vector carrying bone morphogenetic protein 2 and transforming growth factor β3, and to observe the expression of lentivirus vector in bone marrow mesenchymal stem cells. METHODS: The recombinant lentiviral vectors carrying transforming growth factor β3, bone morphogenetic protein 2 and green fluorescent protein were constructed with recombinant lentiviral technology, and then the recombinant lentiviral vectors were used to transfect the passage 3 rabbit bone marrow mesenchymal stem cells in vitro cultured (transfection group). The bone marrow mesenchymal stem cells transfected with single gene lentivirals (single gene transfection group) carrying transforming growth factor β3 and bone morphogenetic protein 2 or single lentivirals were as control (control group). At 1 week after trasfection, the total RNA and protein were extracted from each group for detection. RESULTS AND CONCLUSION: The green fluorescence bone marrow mesenchymal stem cells transfected with transforming growth factor β3 and bone morphogenetic protein 2 gene for 3 days could be observed under fluorescence microscope, and the transfection efficiency was over 90%. Reverse transcription-PCR and Western blot results showed the mRNA and protein expressions of transforming growth factor β3 and bone morphogenetic protein 2 in the transfection group were higher than those in the single gene transfection group and the control group. The results indicate that lentivirus can successful y transfect transforming growth factor β3 and bone morphogenetic protein 2 into the bone marrow msenchymal stem cells and achieve its high expression, and these two genes have the synergistic effect of promoting expression.
ABSTRACT
Using impedance-plethysmography, variations in volume of blood-flow of the calves of 34 young adults were observed under different postures: lying, sitting, standing and squatting.Results showed that blood-flow of the calf was of bigger volume in lying position, smaller volume while standing, still smaller while sitting and still smaller while squatting.Data thus obtained are similar to those by other authors using other methods. If the devices used can be further improyed, dynamic measurement of blood-flow volume of human extremities during physical exercises will also be possible.