Background: Over the past years, scientists have been working on the mechanisms of the scarless healing. The remarkable phenotypic differences between fetal and adult healing may lead us to find out their characterist...Background: Over the past years, scientists have been working on the mechanisms of the scarless healing. The remarkable phenotypic differences between fetal and adult healing may lead us to find out their characteristics in genetics, which represent potentially important mechanisms to explain the differences in the quality of wound repair observed in fetus versus adult tissues. Methods: Middle laparotomy and hysterotomy were performed on pregnant rabbits on 20-day gestation to expose the fetal back, and longitudinal incision which penetrated full skin was made on the back of fetus. The trauma fetus skin was harvested at 12 h post-operation (FT), the fetus control (FC) and trauma adult skin (AT) were taken at the same time. dscDNA was synthesized from total RNA of skin samples with SMART technology. An improved suppression subtractive hybridization (SSH) method was applied to analyze the samples. Having taken one of the three samples as Tester respectively, the other two together as Drivers, one forward and two reverse hybridization products were gotten. Having amplified by selective PCR, the products were inserted into vector, and then transferred into E.coli HB101. The colonies were screened by electrophoresis, reverse Northern afterwards, and the positive clones were sequenced. BLAST in NCBI was performed to compare and analyze the positive clones (expressed sequence Tag, ESTs). Results: Totally 298 clones were gotten and 61 positive clones were obtained after screening. The 61 selected positive clones were sequenced and 54 sequences were goten. Conclusion: Instead of traditional SSH, an improved SSH with 2 Drivers was applied in the experiment. The improved program is reasonable and correct in both theory and practice.展开更多
Objective： The present study was designed to use an in vivo rabbit ear scar model to investigate the efficacy of systemic administration of endostatin in inhibiting scar formation. Methods： Eight male New Zealand wh...Objective： The present study was designed to use an in vivo rabbit ear scar model to investigate the efficacy of systemic administration of endostatin in inhibiting scar formation. Methods： Eight male New Zealand white rabbits were randomly assigned to two groups. Scar model was established by making six full skin defect wounds in each ear. For the intervention group, intraperitoneal injection of endostatin was performed each day after the wound healed （about 15 d post wounding）. For the control group, equal volume of saline was injected. Thickness of scars in each group was measured by sliding caliper and the scar microcirculatory perfusion was assessed by laser Doppler flowmetry on Days 15, 21, 28, and 35 post wounding. Rabbits were euthanatized and their scars were harvested for histological and proteomic analyses on Day 35 post wounding. Results： Macroscopically, scars of the control group were thicker than those of the intervention group. Significant differences between the two groups were observed on Days 21 and 35 （p〈0.05）. Scar thickness, measured by scar elevation index （SEI） at Day 35 post wounding, was significantly reduced in the intervention group （1.09±0.19） compared with the controls （1.36±0.28）. Microvessel density （MVD） observed in the intervention group （1.73±0.94） was significantly lower than that of the control group （5.63±1.78） on Day 35. The distribution of collagen fibers in scars treated with endostatin was relatively regular, while collagen fibers in untreated controls were thicker and showed disordered alignment. Western blot analysis showed that the expressions of type I collagen and Bcl-2 were depressed by injection of endostatin. Conclusions： Our results from the rabbit ear hypertrophic scar model indicate that systemic application of endostatin could inhibit local hypertrophic scar formation, possibly through reducing scar vascularization and angiogenesis. Our results indicated that endostatin may promote the apoptosis of endothelial cells and block their release of platelet-dedved growth factor （PDGF） and fibroblast growth factor （FGF）, thereby controlling collagen production by fibroblasts. Blood vessel-targeted treatment may be a promising strategy for scar therapy.展开更多
文摘Background: Over the past years, scientists have been working on the mechanisms of the scarless healing. The remarkable phenotypic differences between fetal and adult healing may lead us to find out their characteristics in genetics, which represent potentially important mechanisms to explain the differences in the quality of wound repair observed in fetus versus adult tissues. Methods: Middle laparotomy and hysterotomy were performed on pregnant rabbits on 20-day gestation to expose the fetal back, and longitudinal incision which penetrated full skin was made on the back of fetus. The trauma fetus skin was harvested at 12 h post-operation (FT), the fetus control (FC) and trauma adult skin (AT) were taken at the same time. dscDNA was synthesized from total RNA of skin samples with SMART technology. An improved suppression subtractive hybridization (SSH) method was applied to analyze the samples. Having taken one of the three samples as Tester respectively, the other two together as Drivers, one forward and two reverse hybridization products were gotten. Having amplified by selective PCR, the products were inserted into vector, and then transferred into E.coli HB101. The colonies were screened by electrophoresis, reverse Northern afterwards, and the positive clones were sequenced. BLAST in NCBI was performed to compare and analyze the positive clones (expressed sequence Tag, ESTs). Results: Totally 298 clones were gotten and 61 positive clones were obtained after screening. The 61 selected positive clones were sequenced and 54 sequences were goten. Conclusion: Instead of traditional SSH, an improved SSH with 2 Drivers was applied in the experiment. The improved program is reasonable and correct in both theory and practice.
基金supported by the National Natural Science Foundation of China (No.81272120)the Health Department of the Zhejiang Province (No.2007B086),China
文摘Objective： The present study was designed to use an in vivo rabbit ear scar model to investigate the efficacy of systemic administration of endostatin in inhibiting scar formation. Methods： Eight male New Zealand white rabbits were randomly assigned to two groups. Scar model was established by making six full skin defect wounds in each ear. For the intervention group, intraperitoneal injection of endostatin was performed each day after the wound healed （about 15 d post wounding）. For the control group, equal volume of saline was injected. Thickness of scars in each group was measured by sliding caliper and the scar microcirculatory perfusion was assessed by laser Doppler flowmetry on Days 15, 21, 28, and 35 post wounding. Rabbits were euthanatized and their scars were harvested for histological and proteomic analyses on Day 35 post wounding. Results： Macroscopically, scars of the control group were thicker than those of the intervention group. Significant differences between the two groups were observed on Days 21 and 35 （p〈0.05）. Scar thickness, measured by scar elevation index （SEI） at Day 35 post wounding, was significantly reduced in the intervention group （1.09±0.19） compared with the controls （1.36±0.28）. Microvessel density （MVD） observed in the intervention group （1.73±0.94） was significantly lower than that of the control group （5.63±1.78） on Day 35. The distribution of collagen fibers in scars treated with endostatin was relatively regular, while collagen fibers in untreated controls were thicker and showed disordered alignment. Western blot analysis showed that the expressions of type I collagen and Bcl-2 were depressed by injection of endostatin. Conclusions： Our results from the rabbit ear hypertrophic scar model indicate that systemic application of endostatin could inhibit local hypertrophic scar formation, possibly through reducing scar vascularization and angiogenesis. Our results indicated that endostatin may promote the apoptosis of endothelial cells and block their release of platelet-dedved growth factor （PDGF） and fibroblast growth factor （FGF）, thereby controlling collagen production by fibroblasts. Blood vessel-targeted treatment may be a promising strategy for scar therapy.
