Background Pretreatment with chemical agents could alter the surface chemistry of the silicone gel, which makes it suitable for epithelial migration onto its surface and thus enhances the cytobiocompatibility. This st...Background Pretreatment with chemical agents could alter the surface chemistry of the silicone gel, which makes it suitable for epithelial migration onto its surface and thus enhances the cytobiocompatibility. This study aimed to evaluate the biological response of the corneal stroma to porous silicone gel pretreated with different chemical agents in vivo. Methods The porous silicone gels were treated with a mixed acid solution containing 23.2% H2SO4 and 0.8% K2Cr207 for 10 or 15 minutes or with 30% H202 for 15 minutes. Discs （4 mm in diameter） were inserted into interlamellar stromal pockets of New Zealand white rabbits and followed up for a period of 3 months. Clinical evaluations such as corneal infiltration, edema and neovascularization were performed daily. At 3 months, the fibroplasias and collagen deposition were examined under light and scanning electron microscopy （SEM） and by immunohistochemical analysis. Results Pretreatment of the discs obviously decreased conjunctival congestion, discharge, cornea edema, and the extent of neovascularization. More fibroblasts migrated into the pretreated discs than into the control, and collagen was deposited, indicating that the biocompatibility of the corneal replacements was enhanced by the chemical pretreatments. From immunohistochemical analysis, Type I collagen deposition in the pretreated silicone discs was greater than in the control. Conclusions Chemical treatment of silicone gel is effective in decreasing rabbit corneal inflammation, encouraging fibroblast in-growth, and enhancing tissue compatibility. Pretreated gels show good biological stability when used as a skirt material in Keratoprosthesis （Kpros）.展开更多
Heat-resistant silicone gels were synthesized by replacing the single main chain polymethylhydrosiloxane with reactive ladderlike polyhydrosilsesquioxane copolymers. Because of the interaction between polydimethylsilo...Heat-resistant silicone gels were synthesized by replacing the single main chain polymethylhydrosiloxane with reactive ladderlike polyhydrosilsesquioxane copolymers. Because of the interaction between polydimethylsiloxane chains and the ladderlike polysilsesquioxanes chains, the cyclization of the polydimethylsiloxane chains is hindered. The high thermal stability of the ladderlike polymers can improve the thermal stability of the silicone gels without sacrificing their good comprehensive properties.展开更多
背景:中国女性乳腺体积相对偏小,乳腺癌传统保乳手术后乳腺外形欠佳,而采用背阔肌肌皮瓣和横行腹直肌肌皮瓣乳房再造手术难度高、创伤大、术后并发症多,因此行保留乳头乳晕复合体Ⅰ期硅凝胶假体植入乳房重建手术是非常好的选择。目的:...背景:中国女性乳腺体积相对偏小,乳腺癌传统保乳手术后乳腺外形欠佳,而采用背阔肌肌皮瓣和横行腹直肌肌皮瓣乳房再造手术难度高、创伤大、术后并发症多,因此行保留乳头乳晕复合体Ⅰ期硅凝胶假体植入乳房重建手术是非常好的选择。目的:探讨保留乳头乳晕复合体乳腺癌改良根治术后Ⅰ期硅胶假体植入乳房重建的效果。方法:纳入女性乳腺癌患者33例,年龄30-48岁,左侧20例,右侧13例,均于保留乳头乳晕复合体乳腺癌改良根治术后行Ⅰ期硅凝胶假体植入乳房重建治疗,术后通过随访行主客观评价美容效果。结果与结论:33例患者中,术后乳头乳晕复合体坏死2例,自行结痂愈合;1例术中出血量>800 m L,经补液、输血治疗后,恢复良好。随访10-51个月,31例乳房外观良好,双侧乳房对称,优良率达94%,均未发现局部复发及远处转移。证实保留乳头乳晕复合体乳腺癌改良根治术后行硅胶假体Ⅰ期乳房重建,美容效果满意,无严重并发症,手术安全,简单可行。展开更多
基金This study was supported by grants from the National Natural Science Foundation of China （No. 39970779）, Ministry of Health （No. 98-2-158）, and Shandong Scientific and Technological Committee （No. 1999BBCJA3）.Acknowledgements： The authors thank Dr. Edward C. Mignot and Dr. Pamela Holt, Shandong University for assistance in editing the manuscript.
文摘Background Pretreatment with chemical agents could alter the surface chemistry of the silicone gel, which makes it suitable for epithelial migration onto its surface and thus enhances the cytobiocompatibility. This study aimed to evaluate the biological response of the corneal stroma to porous silicone gel pretreated with different chemical agents in vivo. Methods The porous silicone gels were treated with a mixed acid solution containing 23.2% H2SO4 and 0.8% K2Cr207 for 10 or 15 minutes or with 30% H202 for 15 minutes. Discs （4 mm in diameter） were inserted into interlamellar stromal pockets of New Zealand white rabbits and followed up for a period of 3 months. Clinical evaluations such as corneal infiltration, edema and neovascularization were performed daily. At 3 months, the fibroplasias and collagen deposition were examined under light and scanning electron microscopy （SEM） and by immunohistochemical analysis. Results Pretreatment of the discs obviously decreased conjunctival congestion, discharge, cornea edema, and the extent of neovascularization. More fibroblasts migrated into the pretreated discs than into the control, and collagen was deposited, indicating that the biocompatibility of the corneal replacements was enhanced by the chemical pretreatments. From immunohistochemical analysis, Type I collagen deposition in the pretreated silicone discs was greater than in the control. Conclusions Chemical treatment of silicone gel is effective in decreasing rabbit corneal inflammation, encouraging fibroblast in-growth, and enhancing tissue compatibility. Pretreated gels show good biological stability when used as a skirt material in Keratoprosthesis （Kpros）.
基金This project is financially supported by Institute of Materials Research and Engineering, Singapore.
文摘Heat-resistant silicone gels were synthesized by replacing the single main chain polymethylhydrosiloxane with reactive ladderlike polyhydrosilsesquioxane copolymers. Because of the interaction between polydimethylsiloxane chains and the ladderlike polysilsesquioxanes chains, the cyclization of the polydimethylsiloxane chains is hindered. The high thermal stability of the ladderlike polymers can improve the thermal stability of the silicone gels without sacrificing their good comprehensive properties.
文摘背景:中国女性乳腺体积相对偏小,乳腺癌传统保乳手术后乳腺外形欠佳,而采用背阔肌肌皮瓣和横行腹直肌肌皮瓣乳房再造手术难度高、创伤大、术后并发症多,因此行保留乳头乳晕复合体Ⅰ期硅凝胶假体植入乳房重建手术是非常好的选择。目的:探讨保留乳头乳晕复合体乳腺癌改良根治术后Ⅰ期硅胶假体植入乳房重建的效果。方法:纳入女性乳腺癌患者33例,年龄30-48岁,左侧20例,右侧13例,均于保留乳头乳晕复合体乳腺癌改良根治术后行Ⅰ期硅凝胶假体植入乳房重建治疗,术后通过随访行主客观评价美容效果。结果与结论:33例患者中,术后乳头乳晕复合体坏死2例,自行结痂愈合;1例术中出血量>800 m L,经补液、输血治疗后,恢复良好。随访10-51个月,31例乳房外观良好,双侧乳房对称,优良率达94%,均未发现局部复发及远处转移。证实保留乳头乳晕复合体乳腺癌改良根治术后行硅胶假体Ⅰ期乳房重建,美容效果满意,无严重并发症,手术安全,简单可行。
