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ANALYSES OF STRUCTURE OF COLLAGEN FIBRES IN ARTERIAL WALL USING MODERN METHODS OF LIGHT MICROSCOPY
Turčanová, Michaela ; Kochová, Petra (referee) ; Hampl, Aleš (referee) ; Burša, Jiří (advisor)
The doctoral thesis deals with the analysis of the arrangement of collagen fibres in arteries and their correct evaluation and use in structurally motivated constitutive models of the material. The first part of the work is focused on the literature search of mechanical properties of arteries and on an overview of available methods for the detection of waviness, orientation and dispersion of fibres. Most works identify fibre angles as additional parameter from mechanical tests and thus degrade the structural nature of the model. The second part describes an automatic algorithm that can evaluate the local directions of fibres and their scattering from images from a polarizing microscope and structurebased hyperelastic constitutive models. Furthermore, there is an emphasis on choosing the most appropriate imaging method based on fluorescence microscopy, which will help us to distinguish the waviness and scattering of fibres. In the next part of the thesis, two experiments on porcine arteries are presented in order to determine the influence of different magnitudes of biaxial deformation on fiber orientation and dispersion. The last part of the work presents the evaluated structural parameters for porcine and human aortas, which were analyzed not only under polarized light, but also under a laser scanning confocal microscope, thanks to which the waviness of the fibers and their global direction were obtained.
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Nanofiber scaffolds for incisional hernia regeneration
Plencner, Martin ; Amler, Evžen (advisor) ; Kochová, Petra (referee) ; Plášek, Jaromír (referee)
Incisional hernia is the most common postoperative complication which affects up to 20% of patients after abdominal surgery. Insertion of a synthetic surgical mesh has become the standard for care in abdominal wall hernia repair. However, implementation of a mesh does not reduce the risk of recurrence and the onset of hernia recurrence is only delayed by 2-3 years. Nowadays, more than one hundred surgical meshes are available on the market from which the polypropylene is most widely used for abdominal wall hernia repair. Nonetheless, the ideal mesh does not exist yet - it still needs to be developed. The aim of the present study was to develop a functionalized scaffold for abdominal wall hernia regeneration and in vitro testing of the new microsphere system with potential use as a drug delivery system in tissue engineering. We prepared novel composite scaffolds based on a polypropylene surgical mesh functionalized with polycaprolactone nanofibers and adhered either platelet as a natural source of growth factors or a synthetic growth factor. In extensive in vitro tests, we have proven the biocompatibility of polycaprolactone nanofibers with adhered platelets on a polypropylene mesh. A histological and biomechanical evaluation from in vivo tests revealed better healing capacity of our composite...
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