| Because of the staggering complexity of the in vivo environment, systematic study of the cellular response to mechanical stimulations has relied heavily on the use of in vitro preparations. Living cells under mechanical stimulations can make adaptive changes and it must be recognized that different biomechanical stimulations can induce different cellular changes. Morphological change is the most instinctive one and it can also be an indicator for the functional changes in cells. The quantitative study on cellular and sub-cellular morphology and movement by image analyzing system is useful not only in understanding the relations between force simulation and cellular growth, but also in catching on cellular pathological mechanism. However, few image analysis systems are found to suitable for all kinds of images, since images, especially the biological living cellular images, which are sourced by different methods have different characteristics. According to this condition, a new image-processing platform to analyze the cellular changes induced by shear stress and tensile stress has been set up in our lab and the image-processing methods for cellular biomechanical experiments have been detailed studied in this dissertation.The morphological parameters of endothelial cells exposed on shear stress are analyzed in detail and then two novel parameters are suggested. They are named VOA (velocity of oriental angle) and VL (velocity of major axis length) and can reflect velocity in cellular morphological changes.Image segmentation plays a key role in image analysis and it is also the most hardly step in image processing pipeline. As for all the non-overlapping images, one method which has eight steps based on difference arithmetic operators is proposed. Image enhancing, image graying, halation removing, Canny edge detection, mathematical morphology dilation, edge smoothing, mathematical morphological reconstruction are implemented according to the set sequence. As for all the seriouslyoverlapping images, another method which has seven steps based on watershed transform is put forward. These steps in turn are image enhancing, image graying, morphological illumination, mathematical morphological reconstruction, distance transform, marker image extraction, watershed transform.Olympus 1X70 phase contrast inverted microscope is used to observe cellular images and two methods are applied to capture digital images in the construction of image processing hardware. One is through video CCD (JVOC680-EC) equipped with image capture board (VIGA 9000V), the other is through professional digital CCD for microscopy (Pixera 150ES). A system for automatic control illumination of microscope is set up, which can put through the illumination power of microscope according to the set capture schedule and will help decrease the loss of the microscope's bulb. And the images can be captured in a manner of single frame, frame-by-frame or video stream.The cellular mechanical experimental image-processing platform is developed by using Visual C++ 6.0 (Microsoft) programming language. It is an integrated software package, which integrates image acquiring, files managing, image processing, feature extracting, parameter measuring and result outputting together. Because Oriental Object Programming (OOP) skills are applied to this system, the modules in this package are easy to accomplish functional expanding and code implanting.Enormous cellular images are captured through this image-processing platform and the results suggest that video CCD schedule has advantages in capturing video stream with the disadvantages in the image resolution, and digital CCD is very useful in capturing still cellular image because of its relatively high resolution, high sensitivity and less data loss. The superposition of the processed image by either segmentation strategy on the original cell image indicates that the two methods are suitable. By using developed image analysis system, the morphological parameters of rat aortic endothelial cells (RAECs) expo...
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