| Vascularization factor is a kind of substance that can induce and accelerate vascularization. According to recent research, more than thirty kinds of vascularization factors have been found. VEGF (vascular endothelial growth factor) and bFGF (basic fibrolast growth factor) are two important vascularization factors. VEGF is termed VPF (vascular permeability factor), which is the strongest vascularization factor directly acting to vascular endothelial. The major biological actions are: 1.Acculating the proliferation of vascular endothelial cell; 2.Improving the vascular permeability; 3.Changing ECM (extracellular matrix) and making ECM suitably for vascular growth . 4.VEGF is closely related with tumor growth and many diseases occurrence. The mechanism of VEGF is that VEGF secereted by cell acts to VEGFR (vascular endothelial growth factor receptor) in the cell membrane selectively, leading to cell differentiation and vascularization. The expression of VEGF is closely related with the dentity of the micrangium in tissuses and quantity of the newborn blood vessels. bFGF is a polypetide vascularization factor.Investigation showed that many sorts of FGF are the essential growth factors regulating cell proliferation. Acid FGF and basic FGF have been studied deeply now. bFGF is sensitive to acidity and heat, and its isoelectric point is basic . The biologios of bFGF is 10-100 times than that of aFGF . The biological effect of bFGF is very extensive: 1. Inducing mesoderm forming, accelerating morphologic genesis and mitosis; 2. Accelerating muscleblast cell proliferation in early embryo phase, postponing muscleblast cell differentiation; 3. bFGF can accelerate vascular endothelial cell proliferation during the course of tissues reconstruction ,embryogenesis and tumor growth. Action mechanism : A series of signal cascade conducting system will be triggered when bFGF conjugates with bFGFR, Finaly the signal get into nucleus from extracell , leading to cell proliferative action.Hemangioma is the commonest benign tumor in infancy and childhood. Its indidence is about 3-8%. It can occurs in each part of the body, especially in the skin and hypoderm. Secondly hemagioma can be found in oral mucosa and muscle, and it also can be found in skeleton, viscus, brain and so on. Hemangioma is divided into capillary hemangioma,cavernous hemangioma,racemosum hemangioma and mixed hemangioma in clinic. Capillary hemangioma has a character of fast growth, especially in the first year after born. Though hemangioma is benign, it candestroy the tissues around . Some hemangiomas appear to be invading growth, and make cosmetology defect. About fifty percent of hemangiomas occur in head and face, so there will bring great mental load. Hemangioma's basic structure is made up of expansive hyperplasia blood vessels, or tine and cavity filled with blood, fibrolast tissue and fat forming the interval supporting structure. Its major character is the endothelial cell proliferation of blood capillary. Its natural course include proliferative phase,resting phase and extinctive phase.It is unknownd about the positive pathogenesis of hemangioma. Recent research showed that the vascularization factor is important in vascularization. According to recent research , vasculariation include : isolation of protein in ECMï¼›proliferation and migration of endothelial ; formation and recanalization of ECM . Vascularization factor and ECM play important roles during the whole course.Bleomycin-A5 is a kind of anti-tumor drug . The action mechanisam of Bleomycin-A5 is that Bleomycin-A5 can damage DNA synthesized of endothelial cell directly, prevent thymine into DNA and combinate with thymine. Research shows that Bleomycin-A5 can constrain hemangioma proliferation and accelerate hemangioma extinction effectively.We can presume from above datas: Bleomycin-A5probably constrains generation and expression of VEGF and bFGF in cell level, as to attain the objective of treating hemangioma. Therefore we design a str...
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