Objective: Laser capture microdisection has become indispensable to the analysis of the difference of gene expression between human bladder transitional cell and bladder transitional cell carcinoma (BTCC). However,...Objective: Laser capture microdisection has become indispensable to the analysis of the difference of gene expression between human bladder transitional cell and bladder transitional cell carcinoma (BTCC). However, to obtain sufficient RNA from laser-capture microdissected cells is quite difficult. The study was designed to determinc a feasible technical routine to isolate transitional cells from bladder membrane, separate carcinoma cclls from stromal cells and to amplify the RNA isolated from laser-capture microdissected cells. Methods: Bladder transitional cell were obtained from frozen sections of bladder membrane applying LCM, by the same token, BTCC cells from frozen sections of BTCC tissue. Then RNA was extracted and linearly amplified in vitro. The expression levels of β-actin in primary total RNA and amplified RNA were detected using RT-PCR. Results: That RNA integrity was good after LCM was confirmed by control experiment Ⅰ; By control experiment Ⅱ, the correlation between the number of LCM-shooting and RNA quantity undcr arranged conditions was preliminarily confirmed. About 0.5-2.5kb RNA fragments were obtained after RNA amplification and β-actin levels were integral. Conclusion: Laser capture microdissection combined with RNA linear amplification in vitro can be successfully applied to obtain pure objective cells for research. The integrity of the amplified RNA is good and can be employed in further research.展开更多
Relatively to non-traditional and high-energy-beam micro-manufacturing technique, the micro-cutting technology has many merits. For instance, the machining range is bigger, the cost of equipments is much lower, and th...Relatively to non-traditional and high-energy-beam micro-manufacturing technique, the micro-cutting technology has many merits. For instance, the machining range is bigger, the cost of equipments is much lower, and the productivity and machining accuracy are higher. Therefore, the micro-cutting technology will take an important effect on the machining technique of complex shape microparts. In this paper, based on selfly-developed machine tool, the precision cutting technology of complex shape microparts made of metal material was studied by analyzing the modeling method on complex shape, the means of toolpaths layout and the optimal selection for cutting parameters. On the basis of above work, a typical duralumin specimen of high precision, low surface roughness and complex shape micropart was manufactured. This result will provide favorable technical support for farther research on the micro-cutting technology.展开更多
Dicing of fabricated MEMS (microelectromechanical system) devices is sometimes a source of challenge, especially when devices are overhanging structures. In this work, a modified cleaving technique is developed to p...Dicing of fabricated MEMS (microelectromechanical system) devices is sometimes a source of challenge, especially when devices are overhanging structures. In this work, a modified cleaving technique is developed to precisely separate fabricated devices from a silicon substrate without requiring a dicing machine. This technique is based on DRIE (deep reactive ion etching) which is regularly used to make cleaving trenches in the substrate during the releasing stage. Other similar techniques require some extra later steps or in some cases a long HF soak. To mask the etching process, a thick photoresist is used. It is shown that by applying different UV (ultraviolate) exposure and developing times for the photoresist, the DRIE process could be controlled to etch specific cleaving trenches with less depth than other patterns on the photoresist. Those cleaving trenches are used to cleave the wafer later, while the whole wafer remains as one piece until the end of the silicon etching despite some features being etched all the way through the wafer at the same time. The other steps of fabricating and releasing the devices are unaffected. The process flow is described in details and some results of applying this technique for cleaving fabricated cantilevers on a silicon substrate are presented.展开更多
文摘Objective: Laser capture microdisection has become indispensable to the analysis of the difference of gene expression between human bladder transitional cell and bladder transitional cell carcinoma (BTCC). However, to obtain sufficient RNA from laser-capture microdissected cells is quite difficult. The study was designed to determinc a feasible technical routine to isolate transitional cells from bladder membrane, separate carcinoma cclls from stromal cells and to amplify the RNA isolated from laser-capture microdissected cells. Methods: Bladder transitional cell were obtained from frozen sections of bladder membrane applying LCM, by the same token, BTCC cells from frozen sections of BTCC tissue. Then RNA was extracted and linearly amplified in vitro. The expression levels of β-actin in primary total RNA and amplified RNA were detected using RT-PCR. Results: That RNA integrity was good after LCM was confirmed by control experiment Ⅰ; By control experiment Ⅱ, the correlation between the number of LCM-shooting and RNA quantity undcr arranged conditions was preliminarily confirmed. About 0.5-2.5kb RNA fragments were obtained after RNA amplification and β-actin levels were integral. Conclusion: Laser capture microdissection combined with RNA linear amplification in vitro can be successfully applied to obtain pure objective cells for research. The integrity of the amplified RNA is good and can be employed in further research.
基金Sponsored by China Postdoctoral Science Foundation (Grant No2004035530)
文摘Relatively to non-traditional and high-energy-beam micro-manufacturing technique, the micro-cutting technology has many merits. For instance, the machining range is bigger, the cost of equipments is much lower, and the productivity and machining accuracy are higher. Therefore, the micro-cutting technology will take an important effect on the machining technique of complex shape microparts. In this paper, based on selfly-developed machine tool, the precision cutting technology of complex shape microparts made of metal material was studied by analyzing the modeling method on complex shape, the means of toolpaths layout and the optimal selection for cutting parameters. On the basis of above work, a typical duralumin specimen of high precision, low surface roughness and complex shape micropart was manufactured. This result will provide favorable technical support for farther research on the micro-cutting technology.
文摘Dicing of fabricated MEMS (microelectromechanical system) devices is sometimes a source of challenge, especially when devices are overhanging structures. In this work, a modified cleaving technique is developed to precisely separate fabricated devices from a silicon substrate without requiring a dicing machine. This technique is based on DRIE (deep reactive ion etching) which is regularly used to make cleaving trenches in the substrate during the releasing stage. Other similar techniques require some extra later steps or in some cases a long HF soak. To mask the etching process, a thick photoresist is used. It is shown that by applying different UV (ultraviolate) exposure and developing times for the photoresist, the DRIE process could be controlled to etch specific cleaving trenches with less depth than other patterns on the photoresist. Those cleaving trenches are used to cleave the wafer later, while the whole wafer remains as one piece until the end of the silicon etching despite some features being etched all the way through the wafer at the same time. The other steps of fabricating and releasing the devices are unaffected. The process flow is described in details and some results of applying this technique for cleaving fabricated cantilevers on a silicon substrate are presented.