Wyniki wyszukiwania - Biblioteka Nauki

1

Prophylaxis of the contact (glove) dermatitis at dentists

100%

Pohodenko-Chudakova I. O. , Maksimovitch E. V. , Alexandrova N. J. , Kostyukevich A. I.

Engineering of Biomaterials

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2016

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tom Vol. 19, no. 138 spec. iss.

13

2

Ocena możliwości immobilizacji fluorochinolonów do politereftalanu etylenu

100%

Osińska-Jaroszuk M. , Ginalska G. , Miazga-Karska M.

Engineering of Biomaterials

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2007

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tom Vol. 10, no. 67-68

23-24

3

Biomateriały na bazie kolagenu i hydrolizatów elastyny modyfikowane promieniowaniem UV

100%

Skopińska-Wiśniewska J. , Sionkowska A. , Joachimiak R. , Kaźnica A. , Drewa T. , Bajer K. , Dzwonkowski J.

Engineering of Biomaterials

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2007

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tom Vol. 10, no. 69-72

67-69

4

Adhesion and growth on human osteoblast like MG 63 cells in cultures on calcium phosphate-based biomaterials cultures on calcium phosphate-based biomaterials

100%

Bacakova L. , Jungova I. , Ślósarczyk A. , Zima A. , Paszkiewicz Z.

Inżynieria Biomateriałów

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2004

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tom R. 7, nr 38-42

15-18

5

Podatność powierzchni biomateriału na kolonizację bakteriami zależy od rodzaju tej powierzchni

100%

Jakubowski W. , Szymański W. , Okrój W. , Przybyszewska-Doroś I. , Pirek M. , Walkowiak B.

Inżynieria Biomateriałów

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2004

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tom R. 7, nr 38-42

206-207

6

Biomaterial-based regenerative medicine: challenges & opportunities

100%

Kirkpatrick C. J.

Engineering of Biomaterials

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2014

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tom Vol. 17, no. 128-129

1--2

EN

For the author there are three major challenges in Regenerative Medicine (RegMed), namely to develop strategies which are translatable, materials which are functional and methods which are predictive. New strategies in RegMed depend on a concerted interdisciplinary effort between the exact and engineering sciences on the one side and the life sciences on the other. As cells synthesize and reside in an extracellular matrix (ECM), which they remodel, a main focus of biomaterial research is the development of injectable, bioresorbable hydrogels containing biological signals which could be released by tissue responses. These interactive materials will certainly increase in importance in the future. However, a major challenge is how to combine them, for example, in composites with load-bearing capacity relevant for human applications. Where synthetic materials such as metals are still essential, as in orthopaedics and traumatology, there is the possibility of adding such responsive materials as coatings to the bulk material. The use of decellularized matrix is also part of the bioinspired approach to developing biomaterials. In the life sciences great effort is being invested in understanding the so-called „regenerative niche“, which differs from tissue to tissue. Great progress made in stem cell biology has opened up new vistas on the possibility to target a regenerative niche. Cell-cell and cell-matrix interactions remain a central element of this activity. One of the paradigm shifts we need to master is the step from what is usual even in complex cell biological models, namely the use of purely physiological conditions, to a more realistic situation as would be found in the clinical setting. Thus, we need to understand regeneration in hostile environments, which include post-trauma, cancer and multimorbidity. This will be discussed with examples from the author’s own research. One of the important in vitro methods to investigate the mechanisms involved in regeneration is the use of coculture systems with relevant human cells, usually on tissue culture plastic and, as knowledge progresses, on more complex 3D biomaterial scaffolds. As major limiting factors in bone regeneration are the speed and extent of vascularization, we have established human osteoblast (pOB)-endothelial cell (EC) cocultures to study cellular crosstalk and its possible use for translational strategies [1,2]. Concerning the background, if two cell populations, that is, human pOB and human dermal microvascular EC (HDMEC), are seeded as cell suspensions on an open porous biomaterial scaffold, such as can be made from microfibres of the silk protein fibroin, the two cell types will interact in such a way that lumen-containing, capillary-like structures (CLS) will form as a vascular network [3]. Further molecular studies on the cellular crosstalk revealed that the EC induce an upregulation of growth factor and matrix production in pOB, such as VEGF and collagen type I resp. The EC then respond to these signals by promoting the angiogenic phenotype [4,5]. The following additional approaches have been adopted to study CLS formation: use of early embryonic signals, such as sonic hedgehog (shh), to accelerate both osteoand angiogenesis [6,7], use of intermittent hypoxia, but not constant hypoxia, to promote vascular sprout formation, and study of possible stimulatory roles for macrophages in the bone regenerative niche [8]. How this is investigated in coculture models will be discussed in the context of future evelopments. Naturally, all phenomena from in vitro studies require proof of concept in relevant in vivo models, as only this approach can lead to a translational perspective. Thus, we were able to demonstrate that these in vitro pre-formed vessels can rapidly become inosculated, that is, incorporated into the pre-existing microcirculation of host tissue in a subcutaneous implantation model [9]. The major role of the osteoblasts as a natural „drug delivery system“ was shown by the fact that host vascular response can be stimulated by these cells even in the absence of a pre-cultivation with endothelial cells [10]. A further aspect offering a promising perspective for the future is NanoMedicine, which uses advances in nanotechnology for medical applications. For reasons of time this will not be addressed in the context of the presentation. In conclusion, biomaterials, especially so-called responsive biomaterials, are an essential element of modern regenerative medicine, and must be accompanied by state of the art life sciences, from cell and molecular biology to good clinical practice. To achieve this the multidisciplinary approach is a conditio sine qua non.

7

Poly(3,4- ethylenedioxypyrrole) – novel conducting polymer with biomedical applications

80%

Krukiewicz K. , Gniazdowska B. , Turczyn R. , Jarosz T. , Herman A. P. , Boncel S. , Zak J. K.

Engineering of Biomaterials

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2016

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tom Vol. 19, no. 138 spec. iss.

79

8

Influence of incubation time on the surface of nasal splint used in otorhinolaryngology

80%

Łagan S. , Liber-Kneć A.

Engineering of Biomaterials

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2018

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tom Vol. 21, no. 148

12

9

The biocompatibility in vitro study of an innovative elastomer for heart assist devices construction

80%

Kościelniak-Ziemniak M. , Wilczek P. , Kustosz R. , Gonsior M. , Błachowicz A. , El Fray M. , Piegat A. , Piątek-Hnat M.

Engineering of Biomaterials

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2014

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tom Vol. 17, no. 128-129

112--113 [wklejka]

10

One-step fabrication of gentamicin nanoparticles embedded in polymeric biomaterials surface: sonochemical approach

80%

Gołda-Cępa M. , Chytrosz P. , Kotarba A.

Engineering of Biomaterials

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2017

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tom Vol. 20, no. 143 spec. iss.

20

11

Nowe stopy tytanu do zastosowań biomedycznych wytwarzane metodą metalurgii proszków

80%

Deptuła P. , Grądzka-Dahlke M. , Dąbrowski J. R.

Engineering of Biomaterials

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2007

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tom Vol. 10, no. 65-66

13-16

12

Adhesion, differentiation and immune activation of human osteogenic cells in cultures in carbon-fibre reinforced carbon composites

80%

Bacakova L. , Stary V. , Glogar P. , Lisa V.

Inżynieria Biomateriałów

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2003

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tom R. 6, nr 30-33

8-9

13

Physical properties and haemocompatibility of passive-carbon layer

80%

Paszenda Z. , Tyrlik-Held J. , Jurkiewicz W.

Journal of Achievements in Materials and Manufacturing Engineering

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2008

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tom Vol. 31, nr 2

348-355

EN

Purpose: In the paper physical (surface topography, electrical properties) and antithrombogenic properties of the passive-carbon layer used for enhancing the surface properties of vascular stents made of Cr-Ni-Mo steel have been investigated. Design/methodology/approach: To characterize the electrical properties of carbon layer the silicon plate was used. The resistivity ρ and relative permittivity of the layer ε r have been determined on the basis of currentvoltage and capacitance-voltage characteristics. In vitro tests of biotolerance evaluation of the passive-carbon layer in blood environment have been carried out in the haemolysis tests (in the direct contact and from the extract) and in the blood clotting tests. Findings: The results of investigations have shown that deposition process of the passive-carbon layer of dielectric properties on the surface of implants made of Cr-Ni-Mo steel and used in interventional cardiology is an effective way of limiting the reactivity of their surface in blood environment and the blood clotting process in consequence. Research limitations/implications: Usefulness of the passive-carbon layer for interventional cardiology applications should be verified in in vivo tests. Originality/value: Modification of physical properties of surface of the metallic biomaterials applied in cardiovascular system by deposition of the passive-carbon layer which has dielectric properties limits the blood clotting process.

14

Corrosion study of Ti6Al7Nb alloy after thermal, anodic and alkali surface treatments

80%

Chrzanowski W.

Journal of Achievements in Materials and Manufacturing Engineering

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2008

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tom Vol. 31, nr 2

203-211

EN

Purpose: The aim of the work was to work out methods to improve biocompatibility of the Ti6Al7Nb alloy by creating thick, porous layer which ensure corrosion resistance and which could be a base for biological reactions leading to improvements in the tissue bond with the implant. Design/methodology/approach: Surface were prepared using electropolishing, thermal oxidation, thermal oxidation in TiO2 powder, anodic oxidation in NaH2PO4, in NaOH and spark oxidation in H2SO4+H3PO4. The roughness was examined using MSP and LPM. Corrosion resistance tests were carried out in SBF with pH values characterized for neutral, inflammatory and stagnation state. Topographical features were determined using confocal microscope. Findings: The surface treatments guarantee a smooth surface (low value of Ra and RZDIN) or porous surface structure and high corrosion resistance. Topographical parameters of the layer can be altered according to the duration of that process. The corrosion resistance of the specimens anodically oxidized in NaOH and spark oxidized possessed high corrosion resistance in SBF also in SBF with low and high pH value. Research limitations/implications: For the layers, further mechanical, chemical, biological and composition examinations are planed. Practical implications: The paper presents different surface treatments and their influence on corrosion and topographical properties and it could be useful for implant producers to take into consideration one of these methods. Anodic oxidation is a very simple method to ensure high corrosion resistance of implants. Originality/value: The paper presented new approaches to the surface preparation by spark oxidation in the acids and anodic oxidation in NaH2PO4 and NaOH at different parameters which haven't previously been used. There were proposed thermal oxidation in TiO2 powder that was not presented before. The paper compares corrosion resistance and topographical features of the Ti6Al7Nb modified by the new proposed and commonly used techniques.

15

Corrosion behaviour of AISI 316L steel in artificial body fluids

80%

Kajzer W. , Krauze A. , Marciniak J.

Journal of Achievements in Materials and Manufacturing Engineering

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2008

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tom Vol. 31, nr 2

247-253

EN

Purpose: The paper presents the comparison of corrosion resistance of AISI 316L stainless steel in variouscorrosive media such as artificial urine, Tyrode's physiological solution and artificial plasma. Design/methodology/approach: The tests were carried out on samples of the following surfaces: grinded-average roughness Ra=0.31 μ m and electropolished and chemically passivated average roughness Ra=0.10 μ m. The corrosion tests were realized by recording of anodic polarization curves with the use of the potentiodynamic method. The VoltaLab ® PGP 201 system for electrochemical tests was applied. The tests were carried out in electrolyte simulating urine (pH=6-6.4), Tyrode's physiological solution (pH=6.8-7.4) and plasma (pH=7.2-7.6) at the temperature of 37± 1° C. Findings: Surface condition of AISI 316L stainless steel determines its corrosion resistance. The highestvalues of breakdown potentials were recorded for all electropolished and chemically passivated samples in allsimulated body fluids. The highest values of anodic current density were recorded for samples tested in artificialurine, the lowest values were recorded for samples tested in Tyrode's physiological solution. Research limitations/implications: The obtained results are the basis for the optimization of physicochemical properties of the AISI 316L stainless steel. Practical implications: On the basis of the obtained results it can be stated that stainless steel meets the basic biocompatibility criteria and can be applied in reconstruction surgery, operative cardiology and urology. Originality/value: The paper presents the influence of various corrosive media simulating human body fluids on corrosion resistance of AISI 316L stainless steel.

16

Comprehensive biological evaluation of biomaterials used in spinal surgery

80%

Komorowski P. , Kamińska M. , Jakubowski W. , Szymański W. , Walczyńska M. , Siatkowska M. , Działoszyńska K. , Sokołowska P. , Białkowska K. , Wasiak T. , Elgalal M. , Makowski K. , Kierzkowska A. , Ciupik L. , Walkowiak B.

Engineering of Biomaterials

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2017

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tom Vol. 20, no. 143 spec. iss.

23

17

The influence of temperature and pore size on cell growth and proliferation on hydroxyapatite scaffolds

80%

Soukup D. , Bacakova M. , Pabst W. , Gregorova E. , Bacakova L.

Engineering of Biomaterials

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2012

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tom Vol. 15, no. 116-117 spec. iss.

127

EN

Porous biomaterials, especially synthetic porous ceramics, are of significant importance in bone tissue engineering, and there has been rapid growth in the medical use of these biomaterials over the last 50 years. The reason is that they are relatively easy to prepare and are available in unlimited supply, unlike the allografts and autografts that are used in clinical practice. Various hydroxyapatite (HAp) scaffolds can be prepared, using various pore-forming techniques and firing temperatures. The firing temperature significantly affects microstructural parameters such as total porosity, pore size, the interconnected pore network, and also the chemical and phase composition. Last but not least, it also affects the mechanical properties of the samples. Knowledge about these factors is therefore essential for designing a sample with the desired controlled microstructure and properties. In this work, uniaxial pressing has been used for preparing HAp disks from nanocrystalline HAp powder, using saccharose as a pore-forming agent. The highest porosity achieved (after partial sintering at 800°C) was in the range of 64.7-70.6%. The firing temperature significantly affects porosity, pore size, grain size and mechanical strength, whereas the dwell time has only a minor effect on these parameters. After firing, XRD confirmed more than 98.4% HAp in all cases. Mercury porosimetry confirmed the presence of nanosized interstitial voids for partially sintered materials and pore throat sizes of approximately 100μm (much smaller than the pore cavities), which is adequate for bone cell penetration and further ingrowth. After firing at 1200°C, the matrix is more or less fully sintered, and nanosized pores are absent or closed. The biological part of the paper summarizes the results from cell-seeding and cultivation experiments to determine the cell adhesion, proliferation, viability, mitochondrial activity and osteogenic cell differentiation on the scaffolds, and thus the biocompatibility and bioactivity of the scaffolds. The highest values for all these parameters, particularly the number of cells, were on HAp fired at 1200°C. The samples fired at 1200°C were prepared with various pore sizes (in the range of 100 - 800μm). We found that pore size has a non-significant effect on cell colonization, whereas the firing temperature has a major influence. All tested HAp samples showed a remarkable ability to adsorb proteins on their surfaces, namely albumin and fibronectin, and to promote cell adhesion. Some cytotoxic activity was observed on the samples fired at 800 and 1000°C. Possible reasons for this cytotoxicity have been discussed. However, it can be concluded that the HAp samples created in this study and fired at 1200°C hold great promise for bone tissue engineering.

18

Correlation of composition and structure of shark teeth

80%

Prymak O. , Enax J. , Fabritius H. , Raabe D. , Epple M.

Engineering of Biomaterials

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2013

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tom Vol. 16, no. 122-123 spec. iss.

68

EN

In contrast to mammalian teeth with the biomineral phase hydroxyapatite, the shark teeth contain harder mineral phase fluoroapatite with partial substitutions of phosphate by carbonate and of fluoride by hydroxide [1]. Their excellent mechanical properties are due to a special hierarchical structure of the constituting fluoroapatite crystals and organic matrix [2]. The two main structural elements of teeth, i.e. hard and mineral-rich enameloid on the outside and softer and less mineralized dentin on the inside, were structurally, chemically and mechanically characterized [3]. The teeth of two different shark species mako shark (Isurus oxyrinchus) and tiger shark (Galeocerdo cuvier) were investigated and their hierarchical structure by high-resolution scanning electron microscopy presented (Fig.1). X-ray diffraction showed that the inorganic matrix of both enameloid and dentin consisted of fluoroapatite, with a high crystalline phase in enameloid and nanocrystalline phase in dentin. FTIR-spectra of the shark teeth showed the characteristic bands of biological apatite. It was found by thermogravimetry that dentin had a higher content of water, organic matrix and carbonate than enameloid. To investigate the mechanical properties of the teeth in longitudinal and cross sections, nanoindentation and Vickers microhardness were carried out. Both methods gave comparable results: the enameloid of both shark teeth was approximately six times harder than the dentin with an isotropic hardness (longitudinal or cross section).

19

On the nature of silver ions in complex media

80%

Loza K. , Diendorf J. , Sengstock C. , Koller M. , Epple M.

Engineering of Biomaterials

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2014

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tom Vol. 17, no. 128-129

80

EN

Antimicrobial biocides are commonly used to present the growth of bacteria on surfaces and within materials. They are typically added in small quantities to many applications to prevent bacterial growth on the treated object. Silver is increasingly used in many applications due to the aim to replace organic chemical agents by inorganic additives. Examples of applications are bacteriostatic water filters for household use or swimming pool algaecides and numerous devices, ranging from consumer commodities like mobile phones, refrigerators, and clothes to medical devices like catheters, implant surfaces, and plasters. To meet the diversity of application types, many different forms of silver compounds have been developed to serve this market. In particular, there is little information on the types of transformations that silver nanoparticles will undoubtedly undergo in real, complex environments during long-term aging, and the impact of these transformations on their distribution in the environment, bioavailability, and toxicity potential. The biocidal action results from the interaction of silver ions with bacteria. The most potent compounds for a high silver release are soluble silver salts like silver nitrate or silver acetate. These are fully water soluble with a high silver ion release rate. Therefore they are often used as control in cell experiments to elucidate the biological effect of silver nanoparticles. However, in the case of free silver nanoparticles the interactions can be more complex and catalytic reactions on the particle surface which depend on the size and shape of the nanoparticles can render the system very complex. If AgNO3 is used as control, it is tacitly assumed, that the free silver ion concentration is the same as that in the added AgNO3. This obviously cannot be true because of the presence of a whole set of proteins, biomolecules and inorganic ions like Cl- and H2PO4- in the biological medium. These will react with the silver ions in one or the other way. We report on experiments on the behaviour of silver ions in biologically relevant concentrations in different media, from physiological salt solution over phosphate-buffered saline solution to cell culture media. For dissolution and immersion experiments PVP-coated silver nanoparticles were synthesized by reduction with glucose in the presence of PVP. The final silver concentration in all dispersions was determined by atomic absorption spectroscopy. The dissolution of silver nanoparticles was followed in long-term experiments out of a dialysis tube which was permeable only for silver ions. In case of immersion experiments, the nanoparticles and all precipitates were isolated by ultracentrifugation, redispersed in pure water and again subjected to ultracentrifugation. The particles were analyzed by scanning electron microscopy, energy-dispersive X-ray spectroscopy and X-ray powder diffraction. The dissolution requires the presence of dissolved oxygen. If no oxygen is present, only a very small fraction of silver is dissolved, possibly by traces of oxygen in the experimental setup. An oxidizing agent like H2O2 clearly enhances the dissolution. The presence of NaCl, either in pure form or as PBS, strongly slows down the dissolution, probably due to silver chloride formation. Cysteine has a clearly inhibiting effect with almost no dissolution of the silver nanoparticles whereas glucose has a decelerating effect but leads to a similar final dissolved fraction. This suggests that cysteine adsorbs onto the silver nanoparticle surface with its thiol group and prevents the oxidation. In contrast, glucose slows down the dissolution, but clearly did not prevent the oxidation on a longer time scale. We have extended the studies by mixing silver nanoparticle dispersions with different media of increasingly biological nature. The solutions/dispersions were stirred for equilibration and then subjected to ultracentrifugation. All precipitates and nanoparticles were isolated by this way and then analyzed. The results show that both initially present silver ions and released silver ions are mainly precipitated as AgCl if chloride is present. Only in the absence of chloride, glucose is able to reduce Ag+ to Ag0. The initially present silver nanoparticles were recovered in all cases. Silver phosphate was not observed in any case, probably due to the moderate pH (around 7) at which phosphate is mostly protonated to hydrogen phosphate and dihydrogen phosphate. We can conclude that released silver ions precipitate mostly as AgCl in biological media, and that most cell culture studies where silver ions are used as control are in fact studying the effect of colloidal silver chloride on the cells. To prove this assumption, human mesenchymal stem cells (hMSC) were cultured in the presence of silver chloride nanoparticles (diameter 120 nm), and the viability of the cells was analyzed by fluorescence microscopy. In general, we clearly observed that pure silver nanoparticles have lower toxicity to hMSC compared to silver chloride nanoparticles with a comparable total silver dose. Silver acetate in the biological medium had a comparable toxicity to hMSC compared to silver chloride nanoparticles with the same total silver dose.

20

Application of cellulose-based biomaterials in vascular tissue engineering - a review and our experience

80%

Bacakova L. , Novotna K. , Parizek M. , Havelka P. , Sopuch T.

Engineering of Biomaterials

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2012

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tom Vol. 15, no. 116-117 spec. iss.

128--130

EN

Artificial vascular replacements used in current clinical practice are fabricated from polyethylene terephthalate (PET, e.g. Dacron) orpolyterafluoroethylene (PTFE, e.g. Teflon). Older materials used earlier for constructing vascular prostheses are polyamide (Nylon), polyvinyl alcohol (Ivalon) and polyacrylonitrile (Orlon). New promising materials include polyurethane and a wide range of biodegradable synthetic or nature-derived polymers, which are usually designed as temporary scaffolds for vascular cells forming a new regenerated blood vessel wall (for a review, see [1]). One of the nature-derived polymers is cellulose and its derivatives and composites with other materials. Cellulose is the most abundant biopolymer on Earth. It is a polysaccharide consisting of a linear chain of several hundred to over ten thousand ß(1\to 4) linked D-glucose units [2,3]. Cellulose is the structural component of the primary cell wall of green plants, many forms of algae and the oomycetes. In plant cells, cellulose microfibrils are synthesized at the plasma membrane by hexameric protein complexes, also known as cellulose synthase complexes [4]. Some species of bacteria secrete cellulose to form biofilms. For industrial use, cellulose is mainly obtained from wood pulp and cotton. For tissue engineering applications, bacterial cellulose has been predominantly used, mainly that synthesized by Acetobacterxylinum. Bacterial cellulose is identical to plant cellulose in chemical structure, but it can be produced without contaminant molecules, such as lignin and hemicelluloses, and does not require intensive purification processes. In addition, it is remarkable for its mechanical strength, its ability to be engineered structurally and chemically at nano-, micro-, and macroscales, its biocompatibility and chemical and morphologic controllability [5]. Bacterial cellulose has been used for experimental engineering of bone tissue [6], cartilage [7], skin [8], heart valve [9], and also for urinary reconstruction and diversion [10]. One of the first attempts at vascular tissue engineering was made with cellulose fibers, which were used for constructing three-dimensional vascularized tissue in vitro. These fibers were immobilized with fibronectin in order to improve cell adhesion, and were seeded with bovine coronary artery smooth muscle cells. These cells proliferated on the scaffolds and, after they formed multilayers on the fibers, the fibers were removed by enzymatic digestion using cellulase. The remaining smooth muscle cell aggregates maintained lumens after this procedure, and thus mimicked newly-formed blood vessels [11]. Similarly, three-dimensional nanofibrous scaffolds with micropores made of bacterial cellulose allowed attachment and proliferation of human saphenous vein smooth muscle cells on the surface and also in the inside of the scaffolds [12]. In addition, the mechanical properties of nanofibrous bacterial cellulose scaffolds, evaluated by the shape of the stress-strain response, were reminiscent of the properties of the carotid artery, most probably due to the similarity in architecture of the nanofibril network [13]. The adhesion and growth of vascular endothelial cells was also supported by cellulose-based scaffolds, namely by nanofibrous bacterial cellulose or cellulose acetate scaffolds, especially if these scaffolds were functionalized with RGD-containing oligopeptides, i.e. ligands for integrin adhesion receptors on cells [14, 15], or if they were combined with chitosan [16]. The angiogenic response to bacterial cellulose was also observed under in vivo conditions, i.e. after implantation of these scaffolds in the form of dorsal skinfold chambers into Syrian golden hamsters [17]. Cellulose has also been used for creating tubular structures designed for replacing small-caliber vessels. Hollow-shaped segments of bacterial cellulose were created with a length of 10 mm, an inner diameter of 3.0-3.7 mm and a wall thickness of 0.6 -1.0 mm. These grafts were used to replace the carotid arteries of eight pigs. After a follow-up period of 3 months, seven grafts (87.5%) remained patent, whereas one graft was found to be occluded. All patent grafts developed a single inner layer of endothelium with a basement membrane and a thin layer of collagen, followed by a concentric medial layer containing smooth muscle cells and cellulose, and an outer layer of fibrous cells [18]. Similarly, bacterial cellulose grafts 4 cm in length and 4 mm in internal diameter were implanted bilaterally in the carotid arteries of eight sheep. Although 50% of the grafts occluded within 2 weeks, all patent grafts developed a confluent inner layer of endothelial- like cells [19]. In addition, the mechanical properties of tubular structures created from bacterial cellulose seemed to be advantageous for vascular tissue engineering. For example, these structures exhibited a compliance response similar to that of human saphenous vein [20]. In our experiments, we have concentrated on cellulose-based materials modified with oxidation and/or functionalization with biomolecules. We have prepared fibrous scaffolds made of non-oxidized viscose, dialdehyde cellulose and 6-carboxycellulose with 2.1 wt.% or 6.6 wt.% of -COOH groups. In addition, all these material types were functionalized with arginine, i.e. an amino acid with a basic side chain, or with chitosan, in order to balance (compensate) the relatively acid character of oxidized cellulose molecules. Two groups of samples with and without functionalization were then seeded with vascular smooth muscle cells (VSMC) derived from the rat thoracic aorta by an explantation method [21]. We found that the oxidized cellulose with 2.1 wt.% of-COOH groups was the most appropriate of all the tested materials for colonization with VSMC. The cells on this material achieved an elongated shape, while they were spherical in shape on the other materials. In addition, the numbers of cells obtained in one week after seeding and the concentration of alpha-actin and SM1 and SM2 myosins, measured per mg of protein, were significantly higher on oxidized cellulose with 2.1 wt.% of -COOH groups. Functionalization with arginine and chitosan improved the cell adhesion, but usually only slightly. The most apparent increase in cell number after functionalization was observed on oxidized cellulose with 2.1 wt.% of -COOH groups functionalized with chitosan, and on viscose functionalized with chitosan or arginin. However, the cells on all samples proliferated slowly and with a non-significant increase in cell population densities from day 1 to 7 after seeding. This suggests that cellulose-based materials can be used in applications where high proliferation activity of vascular smooth muscle cells is not desirable. They can therefore be used on vascular prostheses, where excessive VSMC proliferation can lead to the restenosis of the graft. Alternatively, cell proliferation might be enhanced by some other more efficient modification. This would require further research.