M. Vandrovcova - Academia.edu (original) (raw)

Papers by M. Vandrovcova

Autologous vein grafts are often used for treating damaged vessels, e.g. arteriovenous fistulas o... more Autologous vein grafts are often used for treating damaged vessels, e.g. arteriovenous fistulas or arterial bypass conduits. Veins have a different histological structure from arteries, which often leads to intimal hyperplasia and graft restenosis. The aim of this study was to develop a perivascular sirolimus-delivery system that would release the antiproliferative drug sirolimus in a controlled manner. Polyester Mesh I was coated with purasorb, i.e. a copolymer of l-lactide and -caprolactone, with dissolved sirolimus; Mesh II was coated with two copolymer layers; the layer with dissolved sirolimus was overlaid with pure purasorb. This arrangement allowed sirolimus to be released for 6 and 4 weeks, for Mesh I and Mesh II, respectively. Mesh II released sirolimus more homogeneously, without the initial burst effect during the first week. However, the cumulative release curve was steeper at later time points than the curve for Mesh I. Both meshes inhibited proliferation of rat vascular smooth muscle cells during 14-day culture in vitro and preserved excellent cell viability. Newly developed sirolimus-releasing perivascular meshes are promising devices for preventing autologous graft restenosis.

Thin Solid Films, 2012

This study is focused on the evaluation of resistance of plasma polymers toward common sterilizat... more This study is focused on the evaluation of resistance of plasma polymers toward common sterilization techniques, i.e. property important for possible use of such materials in biomedical applications. Three kinds of plasma polymers having different bioadhesive natures were studied: plasma polymerized poly(ethylene oxide), fluorocarbon plasma polymers, and nitrogen-rich plasma polymers. These plasma polymers were subjected to dry heat, autoclave and UV radiation treatment. Their physical, chemical and bioresponsive properties were determined by means of different techniques (ellipsometry, atomic force microscopy, wettability measurements, X-ray photoelectron spectroscopy and biological tests with osteoblast-like cells MG63). The results clearly show that properties of thin films of plasma polymers may be significantly altered by a sterilization process. Moreover, observed changes induced by selected sterilization methods were found to depend strongly on the sterilized plasma polymer.

Journal of Biomedical Materials Research Part A, 2012

Cell behavior depends strongly on the physical and chemical properties of the material surface, f... more Cell behavior depends strongly on the physical and chemical properties of the material surface, for example, its chemistry and topography. The authors have therefore assessed the influence of materials of different chemical composition (i.e., glass substrates with and without TiO 2 films in anatase form) and different surface roughness (R a ¼ 0, 40, 100, or 170 nm) on the adhesion, proliferation, and osteogenic differentiation of human osteoblast-like MG63 cells. On day 1 after seeding, the largest cell spreading area was found on flat TiO 2 films (R a ¼ 0 nm). On TiO 2 films with R a ¼ 170 nm, the cell spreading area was larger and the number of initially adhering cells was higher than the values on the corresponding uncoated glass. On day 3 after seeding, the cell number was higher on the TiO 2 films (R a ¼ 0 and 40 nm) than on the corresponding glass substrates and the standard polystyrene dishes. On day 7, all TiO 2 films contained higher cell numbers than the corresponding glass substrates, and the cells on the TiO 2 films with R a ¼ 40 and 100 nm also contained a higher concentration of b-actin. These results indicate that TiO 2 coating had a positive influence on the adhesion and subsequent proliferation of MG63 cells. In addition, on all investigated materials, the cell population density achieved on day 7 decreased with increasing surface roughness. The concentration of osteocalcin, measured per mg of protein, was significantly lower in the cells on rougher TiO 2 films (R a ¼ 100 and 170 nm) than in the cells on the polystyrene dishes. Thus, it can be concluded that the adhesion, growth, and phenotypic maturation of MG63 cells were controlled by the interplay between the material chemistry and surface topography, and were usually better on smoother and TiO 2 -coated surfaces than on rougher and uncoated glass substrates. How to cite this article: Vandrovcova M, Hanus J, Drabik M, Kylian O, Biederman H, Lisa V, Bacakova L. 2012. Effect of different surface nanoroughness of titanium dioxide films on the growth of human osteoblast-like MG63 cells. J Biomed Mater Res Part A

Diamond and Related Materials, 2009

Fullerenes C 60 were deposited on microscopic glass coverslips in the form of continuous layers (... more Fullerenes C 60 were deposited on microscopic glass coverslips in the form of continuous layers (thickness 505 ± 43 nm or 1090 ± 8 nm) or micropatterned layers using a metallic mask with rectangular openings (128 × 98 µm, spacing 50 µm). Below the openings, the fullerenes formed bulges 484 ± 5 nm or 1043 ± 57 nm in thickness. Very thin fullerene films were also found below the metallic bars of the grid. The adhesion and proliferation activities of human osteoblast-like MG 63 cells in cultures on the fullerene layers were similar as that on the control polystyrene dishes and glass coverslips. On the thick patterned layers, the cells grew preferentially in the grooves among the fullerene bulges. Although these grooves occupied only approximately 41% of the surface, they contained from 80% to 98% of the cells. Immunocytochemistry showed that the cells on all tested surfaces formed β 1 integrin-and talin-containing focal adhesion plaques, a β-actin cytoskeleton, and contained osteocalcin, a marker of osteogenic cell differentiation. These results suggest that fullerene C 60 layers can act as good substrates for cell colonization, and could also serve for the construction of micropatterned surfaces for guided cell adhesion and growth.

A novel approach of surface treatment of orthopaedic implants combining electric discharge machin... more A novel approach of surface treatment of orthopaedic implants combining electric discharge machining (EDM), chemical milling (etching) and shot peening is presented in this study. Each of the three techniques have been used or proposed to be used as a favourable surface treatment of biomedical titanium alloys. But to our knowledge, the three techniques have not yet been used in combination. Surface morphology and chemistry were studied by scanning electron microscopy and X-ray photoelectron spectroscopy, respectively. Fatigue life of the material was determined and finally several in-vitro biocompatibility tests have been performed. EDM and subsequent chemical milling leads to a significant improvement of osteoblast proliferation and viability thanks to favourable surface morphology and increased oxygen content on the surface. Subsequent shot-peening significantly improves the fatigue endurance of the material. Material after proposed combined surface treatment possesses favourable mechanical properties and enhanced osteoblast proliferation. EDM treatment and EDM with shot peening also supported early osteogenic cell differentiation, manifested by a higher expression of collagen type I. The combined surface treatment is therefore promising for a range of applications in orthopaedics.

Autologous vein grafts are often used for treating damaged vessels, e.g. arteriovenous fistulas o... more Autologous vein grafts are often used for treating damaged vessels, e.g. arteriovenous fistulas or arterial bypass conduits. Veins have a different histological structure from arteries, which often leads to intimal hyperplasia and graft restenosis. The aim of this study was to develop a perivascular sirolimus-delivery system that would release the antiproliferative drug sirolimus in a controlled manner. Polyester Mesh I was coated with purasorb, i.e. a copolymer of l-lactide and -caprolactone, with dissolved sirolimus; Mesh II was coated with two copolymer layers; the layer with dissolved sirolimus was overlaid with pure purasorb. This arrangement allowed sirolimus to be released for 6 and 4 weeks, for Mesh I and Mesh II, respectively. Mesh II released sirolimus more homogeneously, without the initial burst effect during the first week. However, the cumulative release curve was steeper at later time points than the curve for Mesh I. Both meshes inhibited proliferation of rat vascular smooth muscle cells during 14-day culture in vitro and preserved excellent cell viability. Newly developed sirolimus-releasing perivascular meshes are promising devices for preventing autologous graft restenosis.

Thin Solid Films, 2012

This study is focused on the evaluation of resistance of plasma polymers toward common sterilizat... more This study is focused on the evaluation of resistance of plasma polymers toward common sterilization techniques, i.e. property important for possible use of such materials in biomedical applications. Three kinds of plasma polymers having different bioadhesive natures were studied: plasma polymerized poly(ethylene oxide), fluorocarbon plasma polymers, and nitrogen-rich plasma polymers. These plasma polymers were subjected to dry heat, autoclave and UV radiation treatment. Their physical, chemical and bioresponsive properties were determined by means of different techniques (ellipsometry, atomic force microscopy, wettability measurements, X-ray photoelectron spectroscopy and biological tests with osteoblast-like cells MG63). The results clearly show that properties of thin films of plasma polymers may be significantly altered by a sterilization process. Moreover, observed changes induced by selected sterilization methods were found to depend strongly on the sterilized plasma polymer.

Journal of Biomedical Materials Research Part A, 2012

Cell behavior depends strongly on the physical and chemical properties of the material surface, f... more Cell behavior depends strongly on the physical and chemical properties of the material surface, for example, its chemistry and topography. The authors have therefore assessed the influence of materials of different chemical composition (i.e., glass substrates with and without TiO 2 films in anatase form) and different surface roughness (R a ¼ 0, 40, 100, or 170 nm) on the adhesion, proliferation, and osteogenic differentiation of human osteoblast-like MG63 cells. On day 1 after seeding, the largest cell spreading area was found on flat TiO 2 films (R a ¼ 0 nm). On TiO 2 films with R a ¼ 170 nm, the cell spreading area was larger and the number of initially adhering cells was higher than the values on the corresponding uncoated glass. On day 3 after seeding, the cell number was higher on the TiO 2 films (R a ¼ 0 and 40 nm) than on the corresponding glass substrates and the standard polystyrene dishes. On day 7, all TiO 2 films contained higher cell numbers than the corresponding glass substrates, and the cells on the TiO 2 films with R a ¼ 40 and 100 nm also contained a higher concentration of b-actin. These results indicate that TiO 2 coating had a positive influence on the adhesion and subsequent proliferation of MG63 cells. In addition, on all investigated materials, the cell population density achieved on day 7 decreased with increasing surface roughness. The concentration of osteocalcin, measured per mg of protein, was significantly lower in the cells on rougher TiO 2 films (R a ¼ 100 and 170 nm) than in the cells on the polystyrene dishes. Thus, it can be concluded that the adhesion, growth, and phenotypic maturation of MG63 cells were controlled by the interplay between the material chemistry and surface topography, and were usually better on smoother and TiO 2 -coated surfaces than on rougher and uncoated glass substrates. How to cite this article: Vandrovcova M, Hanus J, Drabik M, Kylian O, Biederman H, Lisa V, Bacakova L. 2012. Effect of different surface nanoroughness of titanium dioxide films on the growth of human osteoblast-like MG63 cells. J Biomed Mater Res Part A

Diamond and Related Materials, 2009

Fullerenes C 60 were deposited on microscopic glass coverslips in the form of continuous layers (... more Fullerenes C 60 were deposited on microscopic glass coverslips in the form of continuous layers (thickness 505 ± 43 nm or 1090 ± 8 nm) or micropatterned layers using a metallic mask with rectangular openings (128 × 98 µm, spacing 50 µm). Below the openings, the fullerenes formed bulges 484 ± 5 nm or 1043 ± 57 nm in thickness. Very thin fullerene films were also found below the metallic bars of the grid. The adhesion and proliferation activities of human osteoblast-like MG 63 cells in cultures on the fullerene layers were similar as that on the control polystyrene dishes and glass coverslips. On the thick patterned layers, the cells grew preferentially in the grooves among the fullerene bulges. Although these grooves occupied only approximately 41% of the surface, they contained from 80% to 98% of the cells. Immunocytochemistry showed that the cells on all tested surfaces formed β 1 integrin-and talin-containing focal adhesion plaques, a β-actin cytoskeleton, and contained osteocalcin, a marker of osteogenic cell differentiation. These results suggest that fullerene C 60 layers can act as good substrates for cell colonization, and could also serve for the construction of micropatterned surfaces for guided cell adhesion and growth.

A novel approach of surface treatment of orthopaedic implants combining electric discharge machin... more A novel approach of surface treatment of orthopaedic implants combining electric discharge machining (EDM), chemical milling (etching) and shot peening is presented in this study. Each of the three techniques have been used or proposed to be used as a favourable surface treatment of biomedical titanium alloys. But to our knowledge, the three techniques have not yet been used in combination. Surface morphology and chemistry were studied by scanning electron microscopy and X-ray photoelectron spectroscopy, respectively. Fatigue life of the material was determined and finally several in-vitro biocompatibility tests have been performed. EDM and subsequent chemical milling leads to a significant improvement of osteoblast proliferation and viability thanks to favourable surface morphology and increased oxygen content on the surface. Subsequent shot-peening significantly improves the fatigue endurance of the material. Material after proposed combined surface treatment possesses favourable mechanical properties and enhanced osteoblast proliferation. EDM treatment and EDM with shot peening also supported early osteogenic cell differentiation, manifested by a higher expression of collagen type I. The combined surface treatment is therefore promising for a range of applications in orthopaedics.