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Interactions of vascular and bone cells with bioactive polymers for construction of tissue replacements
Pařízek, Martin ; Bačáková, Lucie (advisor) ; Smetana, Karel (referee) ; Hrubý, Martin (referee)
This work deals with the interaction of cells with surface-modified existing or newly created materials developed for vascular and bone tissue engineering, and also for controlled drug delivery into implants. In the first part of this work, we modified the surface of the polyethylene foil by Ar plasma, and then we grafted them with bioactive molecules (glycine, polyethylene glycol, albumin) and with C or Au nanoparticles. These modifications improved the chemical and physical characteristics of the material for the adhesion and growth of vascular smooth muscle cells (VSMC), and also for their phenotypic maturation towards the contractile fenotype. In future, these modifications can be also used for material currently used for fabrication of clinically used vascular prostheses in order to increase their biocompatibility. The aim of the second part of this work was to develop a perivascular drug-delivery system that would release the antiproliferative drug Sirolimus. This perivascular system is designed to be wrapped around a venous graft, implanted to the arterial position, such as in the case of the aortocoronary bypass. The system comprises a polyester mesh, which ensures the mechanical stability of the system and of the venous wall, and a copolymer of L-lactide and ε-caprolactone (Purasorb), serving as a...
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Interactions of vascular and bone cells with bioactive polymers for construction of tissue replacements
Pařízek, Martin
This study is focused on the interaction of cells with surface-modified existing or newly created materials designed for vascular and bone tissue engineering, and also for controlled drug delivery into implants. In the first part of the study, the surface of polyethylene foils was irradiated with Ar plasma and then grafted with various bioactive molecules (glycine, polyethylene glycol, albumin) or with colloidal carbon or gold nanoparticles. These modifications adjusted the physical and chemical properties of the material for the adhesion, growth and also phenotypic maturation of vascular smooth muscle cells (VSMC) towards the contractile phenotype. In the second part of the study, we developed a novel perivascular system for controlled drug delivery into autologous vein grafts, currently used for constructing aortocoronary bypasses. The system comprised a polyester mesh, which ensures the mechanical stability of the system and of the venous wall, and a copolymer of L-lactide and ε-caprolactone (Purasorb), which serves as a carrier of the antiproliferative drug Sirolimus. This system inhibited the proliferation of VSMC in vitro and also in vivo in a rabbit model. Finally, we created composite nanofibrous membranes containing a copolymer of L- lactide and glycolide (PLGA) and diamond nanoparticles...
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Interactions of vascular and bone cells with bioactive polymers for construction of tissue replacements
Pařízek, Martin ; Bačáková, Lucie (advisor) ; Smetana, Karel (referee) ; Hrubý, Martin (referee)
This work deals with the interaction of cells with surface-modified existing or newly created materials developed for vascular and bone tissue engineering, and also for controlled drug delivery into implants. In the first part of this work, we modified the surface of the polyethylene foil by Ar plasma, and then we grafted them with bioactive molecules (glycine, polyethylene glycol, albumin) and with C or Au nanoparticles. These modifications improved the chemical and physical characteristics of the material for the adhesion and growth of vascular smooth muscle cells (VSMC), and also for their phenotypic maturation towards the contractile fenotype. In future, these modifications can be also used for material currently used for fabrication of clinically used vascular prostheses in order to increase their biocompatibility. The aim of the second part of this work was to develop a perivascular drug-delivery system that would release the antiproliferative drug Sirolimus. This perivascular system is designed to be wrapped around a venous graft, implanted to the arterial position, such as in the case of the aortocoronary bypass. The system comprises a polyester mesh, which ensures the mechanical stability of the system and of the venous wall, and a copolymer of L-lactide and ε-caprolactone (Purasorb), serving as a...
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Interactions of vascular and bone cells with bioactive polymers for construction of tissue replacements
Pařízek, Martin
This study is focused on the interaction of cells with surface-modified existing or newly created materials designed for vascular and bone tissue engineering, and also for controlled drug delivery into implants. In the first part of the study, the surface of polyethylene foils was irradiated with Ar plasma and then grafted with various bioactive molecules (glycine, polyethylene glycol, albumin) or with colloidal carbon or gold nanoparticles. These modifications adjusted the physical and chemical properties of the material for the adhesion, growth and also phenotypic maturation of vascular smooth muscle cells (VSMC) towards the contractile phenotype. In the second part of the study, we developed a novel perivascular system for controlled drug delivery into autologous vein grafts, currently used for constructing aortocoronary bypasses. The system comprised a polyester mesh, which ensures the mechanical stability of the system and of the venous wall, and a copolymer of L-lactide and ε-caprolactone (Purasorb), which serves as a carrier of the antiproliferative drug Sirolimus. This system inhibited the proliferation of VSMC in vitro and also in vivo in a rabbit model. Finally, we created composite nanofibrous membranes containing a copolymer of L- lactide and glycolide (PLGA) and diamond nanoparticles...
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Growth of human adipose-derived stem cells on Ti-6Al-4V alloy with various surface modifications
Kročilová, Nikola ; Bačáková, Lucie ; Pařízek, Martin ; Havlíková, Jana ; Motarjemi, H. ; Molitor, M. ; Gabor, R. ; Marvan, J.
Adipose-derived stem cells (ASCs) are of a great importance for bone tissue engineering. We compared ASCs obtained by liposuction under two pressures (-200 mmHg and -700 mmHg). The number and proliferation activity of cells isolated under -700 mmHg (ASC-H) were higher than in cells isolated under -200 mmHg (ASC-L). However, the ASC-L was more active in osteogenic differentiation, as manifested by a higher intensity of fluorescence of alkaline phosphatase and osteocalcin in these cells. The adhesion and growth of ASCs were then studied on Ti-6Al-4V samples either unmodified (K, roughness parameter R-a = 280 nm) or modified by shot blasting and tarnishing A, R-a = 200 nm), vibratory finishing (B, R-a = 100 nm) and vibratory finishing, shot blasting and polishing (C, R-a = 80 nm). All modified samples were more wettable than the K samples. On day 1 after seeding, the size of cell spreading area on some modified samples was lower than on K samples, namely on B samples in ASC-L, on B and C in ASC-H and on A in control MG-63 cells. On day 3, the cell number on some modified samples became higher than on K samples, namely on C samples (ASC-L), on B (ASC-H) and on B and C s (MG-63 cells). On day 7, the numbers of ASC-H and MG-63 cells on all modified samples evened out and became significantly higher than on K samples. On ASC-L samples, the highest cell numbers were obtained on A samples. Thus, all studied modifications of Ti-6Al-4V enhanced growth of ASCs and human osteoblast-like MG-63 cells.
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Growth and differentiation of human osteoblast-like cells on TI-6AL-4V alloy modified with anodization
Doubková, Martina ; Bačáková, Lucie ; Pařízek, Martin ; Vandrovcová, Marta ; Musílková, Jana ; Lisá, Věra ; Gabor, R. ; Marvan, J.
Titanium and its alloys are widely used as hard tissue implants for their high biocompatibility and suitable physical properties. Along with other surface treatment methods, anodization technique is known to enhance osseointegration. The aim of this study is to evaluate the adhesion, growth and osteogenic differentiation of human osteoblast-like SAOS-2 cells on Ti-6Al-4V samples anodized in electrolytes composed of a stable volume of KOH (336.48 g/l) and variable volumes of liquid glass (124.47 g/l, 84,12 g/l and 37.38 g/l; samples s5, s6 and s7, respectively). Non-anodized Ti-6Al-4V samples, cell culture polystyrene (PS) and microscopic glass coverslips served as control materials. On days 2 and 4 after seeding, the cell number did not differ significantly among the tested samples. However, on day 7, the cell number on s6 samples reached the lowest values, which could be attributed to a non-homogeneous TiO2 film on s6 samples formed during anodization. Nevertheless, the osteogenic differentiation, estimated by the intensity of fluorescence of collagen I in cells grown in a differentiation medium, was the highest on s6 samples. On s5 samples, coated with homogeneous TiO2 films, both cell numbers and intensity of fluorescence of collagen I was relatively high. The bone matrix mineralization, evaluated by Alizarin Red staining, was the highest on s5 samples in standard culture medium, and similar on all tested samples in differentiation medium. Thus, the surface modification of s5 samples could be considered the most suitable for application in bone implants.
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Polymeric nanofibrous scaffolds reinforced with diamond and ceramic nanoparticles for bone tissue engineering
Bačáková, Lucie ; Pařízek, Martin ; Staňková, Ľubica ; Novotná, Katarína ; Douglas, T.E.L. ; Brady, M. A. ; Kromka, Alexander ; Potocký, Štěpán ; Stránská, D.
Three types of nanofibrous scaffolds were prepared by electrospining: (1) poly(lactide-co-glycoside) (PLGA) scaffolds reinforced with 23 wt.% of diamond nanoparticles (DNPs), (2) poly(L-lactide) (PLLA) scaffolds with DNPs in concentration ranging from from 0.4 wt.% to 12.3 wt.%, and (3) PLLA scaffolds with 5 wt.% or 15 wt.% of hydroxyapatite (HAp) nanoparticles. The diameter of the nanofibers ranged between 160 and 729 nm. The nanofibers with nanoparticles were thicker and the void spaces among them were smaller. Mechanical properties of the nanoparticle-loaded scaffolds were better, as demonstrated by a rupture test in scaffolds with DNPs and by a creep behavior test in scaffolds with HAp. On PLGA scaffolds with DNPs, the human osteoblast-like MG-63 cells adhered in similar numbers and grew with similar kinetics as on pure PLGA scaffolds. Human bone marrow mesenchymal stem cells grew faster and reached higher population densities on PLGA-DNP scaffolds. However, on PLLA-based scaffolds, the activity of mitochondrial enzymes and concentration of osteocalcin in MG-63 cells decreased with increasing DNP concentration. On the other hand, the metabolic activity of MG-63 cells and content of osteocalcin in these cells were positively correlated with the HAp concentration in PLLA scaffolds. Thus, PLGA nanofibers with 23 wt% of DNPs and PLLA nanofibers with 5 and particularly 15 wt.% of HAp seem to be promising for bone tissue engineering.
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Užitkové rostliny v zahradní a krajinářské tvorbě
Pařízek, Martin
This thesis deals with useful plants and their use in garden and landscape design. In the theoretical part of this work are described ways how was possible to work with this group of plants in the history and there are also mentioned current trends and their use in the private or public greenery, demonstrated on the examples of realization from the Czech Republic and abroad. Briefly are described the specifics of useful species of plants, which affects the design, realization and maintenance of vegetation elements with their representation. The practical part of this work consists of project of gardens in Capuchin monastery in Brno. The study is based on analysis of natural conditions, historical documentation and requirements of Brno for the reconstruction and access to the object. In place of historically documented utility gardens is designed a new smaller public space with a significant number of useful plants. There were used old varieties of fruit trees and unusual species of fruit and vegetable. One terrace is dedicated to the beds of herbs.
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