Wyniki wyszukiwania - BazTech

1

Influence of the different composites (PLA/PLLA/HA/β-TCP) contents manufactured with the use of additive laser technology on the biocompatibility

Woźna Anna E., Junka Adam, Hoppe Viktoria W.

Acta of Bioengineering and Biomechanics

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2021

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Vol. 23, no. 2

169--180

EN

Purpose: In recent years, it has become extremely important to search for more and more natural and biocompatible materials that allow for the reconstruction of natural tissues with as few side effects as possible. The aim of the present paper is to define mechanical properties such as compressive stress and Young’s Modulus and to estimate the ability of human bone cell strains to form biofilm on bioresorbable composites manufactured of polylactide and poly-l-lactide (PLA and PLLA) and hydroxyapatite and tricalcium phosphate (HA and β-TCP) with the use of Selective Laser Sintering (SLS) method. Methods: Microbiological tests were conducted on three variants of solid specimen made with additive laser technology. Samples with different chemical compositions were made with appropriate manufacturing parameters ensuring stability of both composite ingredients. Microbiological in vitro tests helped to determine cytotoxicity of specific samples toward bone cells. Results: The results obtained indicate significantly increased ability of osteoblasts to form colonies on the surface of materials with higher content of hydroxyapatite ceramics compared to surfaces of lower hydroxyapatite content. Conclusions: The data provided can be useful for future applications of the SLS technology in production of bioresorbable PLA/PLLA/HA/β-TCP medical implants.

2

Ostogenic potential of human adipose-derived ASC52telo cell line

Truchan Karolina, Lelek Karolina, Osyczka Anna Maria

Engineering of Biomaterials

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2019

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Vol. 22, no. 153 spec. iss.

82

3

CNTs alter the biocompatibility of PAN-derived CNFs

Benko A., Kolecka B., Nocuń M., Menaszek E., Błażewicz M.

Engineering of Biomaterials

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2017

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Vol. 20, no. 143 spec. iss.

71

4

Antimicrobal and ostheointegration activity of bone cement contains nanometals

Świeczko-Żurek B.

Journal of Achievements in Materials and Manufacturing Engineering

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2016

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Vol. 74, nr 1

15--21

EN

Purpose: One of the major problems in bone surgery are infections – especially those occurring in the course of the operating on the patients with lowered immunity system, because they carry the danger of complications. In the Mechanical Department of Technical University of Gdansk, there has been carried the research with the use of bone cement and metal nanoparticles. Design/methodology/approach: The bone cement was used without supplement or with one or two drugs. These experiments are the latest, because include pure bone cement (without drugs) with nanometals. The titanium specimens was covering with such compose coating. The implant was inserted into rat`s thigh for six weeks. Afterwards the implant was removed from the body and examined by means of scanning electron microscope. Simultanously biological research was carried out. Bonless samples were placed into bacterial liquid, generated by the researcher (the Patent number P 409082 ) containing five most frequently occurring bacteria in human body. Findings: Result of the SEM research was positive – there was good adhesion of ostheoblasts to the surface and there were no traces of infection. Practical implications: The research concerns bone cement with nanoparticles proves, that nanoparticles are the alternatives to antibiotics.

5

Ocena stopnia proliferacji komórek osteoblastopodobnych w kontakcie z powierzchniami stopu tytanu po piaskowaniu do różnego stopnia chropowatości

Bociąga D., Olejnik A., Jastrzębski K., Sobczyk-Guzenda A., Paradowska J.

Engineering of Biomaterials

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2016

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Vol. 19, no. 134

8--17

PL

Tytan i jego stopy są jednymi z najpopularniejszych biomateriałów metalicznych stosowanych w dzisiejszej implantologii. Mimo licznych zalet tych materiałów, wykonane z nich wszczepy często poddaje się dodatkowej obróbce powierzchni, której celem jest polepszenie integracji implantu z otaczającymi go tkankami. Spośród wielu dostępnych technik, jedną z najczęściej wykorzystywanych komercyjnie jest stosunkowo tania i szybka metoda piaskowania, polegająca na wystawianiu danego przedmiotu na kontakt ze strumieniem przyspieszonych cząstek materiału ściernego. Celem tej pracy była analiza wpływu piaskowania ścierniwem o różnej średnicy ziaren na właściwości obrabianej powierzchni elementów na bazie dwóch popularnych stopów tytanu: Ti-6Al-4V i Ti-6Al-7Nb. W celu scharakteryzowania uzyskanych powierzchni przeprowadzono badania ich topografii, składu chemicznego, chropowatości i zwilżalności. Ponadto, aby sprawdzić potencjalną reakcję organizmu na obecność obrobionych w ten sposób elementów dokonano oceny stopnia proliferacji ludzkich komórek kościotwórczych hodowanych w bezpośrednim kontakcie z przygotowanymi powierzchniami. Otrzymane wyniki wykazały wyraźną zależność pomiędzy stopniem chropowatości i składem chemicznym piaskowanych elementów, a zastosowanym do obróbki rodzajem medium ściernego. Badanie zachowania komórek będących w kontakcie z modyfikowanymi próbkami wykazało obniżoną skłonność osteoblastów do przylegania i namnażania na najbardziej chropowatych powierzchniach.

EN

Titanium and its alloys are very popular metallic biomaterials used for medical implants production. Despite numerous advantages of the bulk material, such implants are very often subjected to additional surface treatment in order to improve their integration within the body tissues. Besides many other available techniques, one of the most frequently used in the commercial sector is a fast and economically profitable process of abrasive blasting. It is a method in which a stream of accelerated particles collides with the implant surface what causes changes in the material properties. The following paper presents differences resulting from sandblasting of Ti-6Al-4V and Ti-6Al-7Nb specimens with blasting particles varying in size. In order to characterize the outcome of such the treatment, investigations of surface topography, chemical composition, roughness, and wettability were conducted. Finally, the behaviour of the osteoblast- -like cells adhered to the sandblasted Ti-6Al-4V and Ti-6Al-7Nb surfaces was assessed in order to evaluate potential body response towards the aforementioned materials. The results suggest a strong correlation between surface roughness, its chemistry and the type of blasting medium applied. Evaluation of the cell culture revealed a rapid decrease in cell proliferation rate onto the roughest surfaces.

6

Chitosan/β-1,3-glucan/HA bone scaffold possesses osteopromotive properties in vitro

Przekora A., Ginalska G.

Engineering of Biomaterials

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2016

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Vol. 19, no. 138 spec. iss.

51

7

Effect of polylactide modification with β-TCP and lecithin on the properties of the material as a substrate for osteoblasts

Olkowski R., Stefanek A., Kaszczewski P., Ciach T., Lewandowska-Szumieł M., Kalaszczyńska I.

Engineering of Biomaterials

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2015

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Vol. 18, no. 131

8--11

EN

Polylactide (PLLA) containing β-TCP is biodegradable composite and an attractive biomaterial for bone tissue engineering, however, hydrophobicity of PLLA based composites is major limitation for their use as scaffolds for cell culture. In our study lecithin was used to improve hydrophilicity and cytocompatibility of PLLA/ β-TCP composite. Thin films of PLLA, PLLA/ β-TCP and PLLA/β-TCP/lecithin were manufactured by solvent-casting technique. Comparative analysis of all types of films was performed. Addition of β-TCP did not change hydrophilicity of PLLA. The hydrophilicity of PLLA/β-TCP/lecithin increased in comparison to PLLA and PLLA/β-TCP. Degradation of PLLA/β-TCP composite surpassed the degradation of PLLA while addition of lecithin diminished the degradation of composite. The cytocompatibility of composites were studied in 7 day long in vitro assay. Human bone derived cells were seeded on all tested surfaces. Cell viability was estimated by Live/Dead fluorescent staining and Alamar Blue test. Surprisingly, although lecithin addition improved hydrophilicity of the PLLA-based composite, adhesion and proliferation of human bone derived cells were markedly hampered on PLLA/β-TCP/lecithin in comparison to PLLA and PLLA/β-TCP. Despite positive effect we found of lecithin addition on hydrophilicity and stability of PLLA-based composite, its effect on cell attachment and proliferation is negative. Hence, incorporation of lecithin did not improve properties of PLLA/β-TCP/lecithin composite intended for bone tissue regeneration.

8

Black Orlon as promising material for bone tissue engineering

Parizek M., Vetrik M., Hruby M., Lisa V., Bacakova L.

Engineering of Biomaterials

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2014

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Vol. 17, no. 128-129

4--6

9

Tissue engineering of bone: the role of osteoblasts in osteogenesis and peri-implant bone healing

Wróbel E., Witkowska-Zimny M.

Engineering of Biomaterials

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2013

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Vol. 16, no. 119

2--7

EN

Osteoblasts are cells of mesenchymal origin, which rebuild resorbed bone by synthesizing bone matrix proteins and by inducing bone matrix mineralization. Osteoblasts play a crucial role in creating and maintenance of healthy bone architecture, bone repair, and peri-implant bone healing (osseointegration). These bone-forming cells are also involved in regulation of osteoclasts function, and hence bone resorption in osteoclastogenesis process. We have presented our own studies on the subsequent stages of differentiation of Human Bone-Derived Cells (HBDCs) that could be a good candidate as an autogenous source for reconstruction and rebuilding of own patient's bone using tissue engineering methods. In this review we discussed the biology of osteoblasts, compared with the HBDCs cultures, under the influence of growth factors (FGF-2, TGF-ß, IGF, PDGF) and hormones (PTH, 1,25-dihydroxyvitamin D3, leptin). Our review is also focused on the participation of intercellular adhesion proteins (cadherins, claudins, connexin, 'OsteoMacs'), transcription factors (Cbfal, Msx-2, Osx, ATF4), and others molecules (RANKL, OPG, BMP2, lactofferin, PPARY) in modulating osteoblasts functions on the basis of current reports, throwing new light on the involvement of osteoblasts during osteogenesis and peri-implant bone healing.

10

Adhesion, growth and differentiation of human osteoblast-like cells on thermally oxidized Ti and TiNb substrates

Bacakova L., Vandrovcova M., Jirka I., Novotna K., Stary V.

Engineering of Biomaterials

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2013

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

75--76

EN

Metallic materials are essential for construction of load-bearing bone implants, such as replacements of hip, knee and other joints. For these applications, modern materials used in advanced tissue engineering, e.g. resorbable porous or fibrous polymeric and ceramic scaffolds are mechanically insufficient, even if these materials enable the ingrowth of bone cells and bone tissue formation. Therefore, searching for new metallic materials and their surface modifications improving their biocompatibility and osseointegration is still desirable. As first metallic materials for bone implantation, AISI 316L stainless steel and Co-Cr alloys were used. In the 1950’s, the Ti-6Al-4V alloy was developed. These materials are still frequently used for construction of implants because of their relatively low price [1]. However, these materials are biomechanically incompatible with the bone tissue, because their Young’s modulus is markedly higher (110-220 GPa) than that of the bone (10-40 GPa). Implants with high stiffness take over a considerable part of load from the bone. This phenomenon, referred as “stress-shielding effect”, can then cause the bone resorption and loosening of the implant [1]. Also chemical compositions of the mentioned metallic materials limit their biocompatibility, because they contain harmful elements as V, Al, Co and Cr, which can act as cytotoxic, catabolic, immunogenic or even carcinogenic agents [2,3], and can also cause serious neurological problems [4]. Due to these adverse reactions, new types of Ti-alloys have been developed, namely low-rigidity β-type Ti alloys, containing non-toxic and non-allergenic elements (Nb, Ta, Zr etc.) and having good mechanical properties and workability [4,5]. The goal of this study was to evaluate the adhesion, growth and differentiation of osteoblast-like MG-63 and Saos-2 cells on titanium-niobium alloys after their surface modification by thermal oxidation at two different temperatures (165°C and 600°C). Pure titanium (treated at 165°C and 600°C) and polystyrene culture dishes (PS) were used as control materials. Possible immune activation of the cells was tested by the levels of TNF-alpha secreted to the cell culture media by murine macrophage-like RAW 264.7 cells cultured on the tested materials. On samples treated at 165°C, the number of initially adhered MG-63 and Saos-2 cells was on an average higher on TiNb than on Ti or PS. On day 3 after seeding, the trend of the cell numbers remained similar, with the highest cell density found on TiNb. Similar results were obtained on samples treated at 600°C, where the difference in cell number between TiNb and Ti samples became more apparent. This cell behavior could be attributed to a less negative zeta potential on TiNb samples. In samples treated at 165°C, the zeta potential of TiNb surfaces was on the average less negative than on Ti surfaces, but this difference was not significant. However, in samples treated at 600°C, this difference became much more pronounced, which was probably due to the formation of T-Nb2O5 phase on the surface of the TiNb samples. This phase was of a crystalline structure, while at 165°C, the structure of Nb2O5 was amorphous. In addition, both Ti and TiNb samples treated at 600°C contained rutile, while the samples treated at 165°C contained anatase in their surface layer. It has been shown that rutile films deposited on PEEK enhanced the adhesion and growth of osteoblasts more than anatase films [6]. This phenomenon was explained by an increase in the material surface wettability, and particularly to the presence of –OH- groups on the rutile films. The expression of collagen I and osteocalcin, i.e. an early and late marker of osteogenic cell differentiation, respectively, was higher on Ti than on TiNb samples, and this difference was more apparent in samples treated at 165°C. At the same time, no considerable immune activation of the cells on all tested samples was found. The production of TNF-α by RAW 264.7 cells was very low in comparison with cells grown in the presence of bacterial lipopolysaccharide, and also significantly lower than on untreated samples. These results indicate that TiNb substrates increased the proliferation of human bone cells, while pure Ti rather supported the cell differentiation. The effect on cell proliferation was more apparent in samples treated at the higher temperature (600°C), while the effect on cell differentiation was more pronounced at the lower temperature (165°C). None of the tested samples induce significant cell proinflammatory activation. Thus, all tested samples are suitable as carriers for bone cells; only an appropriate application (i.e., requiring either proliferation or quick differentiation of osteogenic cells) should be selected.

11

The adhesion and growth of human osteoblast-like MG 63 cells in cultures on titanium modified with gold microparticles and polyethylene imine)

Parizek M., Base T., Hruby M., Lisa V., Bacakova L.

Engineering of Biomaterials

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2012

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

149--150

EN

Metallic materials are indispensable for construction of surgical implants, particularly those designed for load-bearing application, such as the bone-anchoring parts of big joint replacements. For good osteointegration, long-term function, durability and also mechanical and chemical resistance of the implant, the physical and chemical properties of the material surface are of a great importance. These properties can be favorably influenced by coating the bone-anchoring parts of the implants with appropriate biocompatible and bioactive films. Therefore, in this study, we have investigated the adhesion and growth of human osteoblast-like MG 63 cells in cultures on titanium substrates coated with films made of gold microparticles and/or poly(ethylene imine) (PEI). Gold microparticles were chosen for good biocompatibility of gold and absence of its cytotoxicity, which has been proved by numerous studies performed in vitro and in vivo [1,2]. When deposited on the material surface, these microparticles provide this surface with microstructure, which has been reported to enhance the osteogenic differentiation of bone-derived cells. On the other hand, the material surface microroughness has dual effect on the cell adhesion, spreading and proliferation - some studies reported the enhancement, other the reduction of these events (for a review, see [3,4]). This suggests that not only the size of the microscale irregularities, but also their shape should be taken into account. Therefore, in our study, gold microparticles were used in the form of plates or polyhedral crystals [5]. These microparticles were deposited on square samples of Ti (1x1 cm, thickness 1 mm) and annealed with a hydrogen flame. As for PEI, this polymer has been used as precursor base layer for further functionalization of metallic substrates, particularly with polyelectrolyte multilayer films [6] or biomolecules such as gelatin, hyaluronan or chitosan [7,8]. Other reason for the PEI deposition was creation of an intermediate layer which would compensate the differences in mechanical properties (e.g., hardness, toughness, specific weight) between a metallic implant and bone tissue. PEI was deposited either on pure or on gold microparticle-coated Ti samples. The materials were sterilized with 70% ethanol (1 hour), inserted into 24-well polystyrene plates (well diameter 1.5 cm; TPP, Switzerland) and seeded with human osteoblast-like MG 63 cells (30 000 cells/well, i.e. 17 000 cells/cm2). Each well contained 1.5 ml of a medium DMEM with 10% of fetal bovine serum and 40 /jg/ml of gentamicin. On days 1, 3 and 7 after seeding, the cell number and morphology were evaluated. For evaluating the cell number, the cells were trypsinized and counted in Bürker hemocytometer. For evaluating the cell morphology, i.e. the cell shape and the size of cell spreading area, the cells were fixed with 70% ethanol (-20°C, 10 min) and stained with a combination of fluorescence dyes Texas Red C2-maleimide, which stains the cell membrane and cytoplasm, and Hoechst #33342, which stains the cell nuclei. The microphotographs of cells were taken using an Olympus IX 51 microscope equipped with a DP 70 digital camera, and the cell spreading area was measured on these pictures using a software Atlas (Tescan, Brno, Czech Rep.) One day after seeding, the highest number of initially adhered cells was found on the surface modified by gold polyhedral crystals. This trend was the same on days 3 and 7 after seeding (FIG.1,2). However, the cell number on Ti modified with gold plates was significantly lower than on Ti with polyhedral crystals. Nevertheless, the numbers of cells on Ti samples coated with gold microparticles without PEI were significantly higher than on PEI-coated samples. Also the cell spreading areas were significantly larger on the samples without PEI. The cells on the samples without PEI were mostly polygonal, while the cells on PEI-coated samples were of star-like appearance, i.e. with multiple long protrusions (FIG.2). This is in accordance with findings published by other authors, documenting cytotoxic effects of PEI, particularly that of a high molecular weight [6], which was also used in our study (m.w. 750 kDa). Nevertheless, this cytotoxicity was considerably reduced by further functionalization of PEI with biomolecules, such as gelatin, hyaluronan or chitosan [7,8]. Thus, it can be concluded that the modification of titanium plates by gold microparticles supported the adhesion and growth of MG 63 cells. In this context, the polyhedral crystals were more advantageous than plates. The effects of PEI coatings on cell behavior need further investigation.

12

Artificial extracellular matrices of collagen fibrils and lactoferrin as coatings to enhance osteoblast behavior

Vandorovcova M., Bacakova L., Dubruel P., Douglas T. E. L.

Engineering of Biomaterials

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2012

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

132--134

EN

Lactoferrin, a glycoprotein found in milk, has stimulated osteoblast proliferation and differentiation, but has remained relatively unexplored as a biomaterial component. In this study, artificial extracellular matrices consisting of fibrils of collagen type I containing lactoferrin were used as coatings for the biocompatible polymer poly(lactic-co-glycolic acid) (PLGA). The numbers of cells, their viability and proliferation rate were evaluated in various time intervals. Additionally, cell initial spreading area on day 1 was measured. The results show that lactoferrin accelerates fibril-logenesis, leads to increased osteoblast cell numbers 1 and 3 days post-seeding, and encourages their proliferation in each of the tested time intervals.

13

Analiza zmian w ekspresji genów cyklu komórkowego w komórkach osteoblastów hodowanych na powierzchniach stopów tytanu

Walkowiak-Przybyło M., Komorowski P., Jakubowski W., Klimek L., Walkowiak B.

Engineering of Biomaterials

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2012

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

46--48

14

Wpływ poli(ε-kaprolaktonu) na ekspresję i aktywność fosfatazy alkalicznej w ludzkich komórkach osteogennych

Leszczyńska J., Wójtowicz J., Olkowski R., Komasa J., Ulański P., Lewandowska-Szumieł M.

Engineering of Biomaterials

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2011

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Vol. 14, no. 103

13--16

PL

Poli(ε-kaprolakton) jest materiałem wykorzystywanym jako rusztowanie dla komórek w inżynierii tkankowej kości. Na podstawie danych z literatury oraz naszych własnych badań nad reakcją komórek osteogennych na bezpośredni kontakt z poli(ε-kaprolaktonem) można przypuszczać, iż materiał ten może wpływać na poziom markerów różnicowania komórek w kierunku osteoblastów. Celem niniejszej pracy było zbadanie wpływu poli(ε-kaprolaktonu) na ekspresję oraz aktywność wczesnego markera procesu różnicowania komórek osteogennych, jakim jest fosfataza zasadowa. Przy użyciu reakcji łańcuchowej polimerazy DNA z analizą ilości produktu w czasie rzeczywistym (real-time PCR) analizowano ekspresję genu fosfatazy zasadowej natomiast aktywność enzymu oznaczono kolorymetrycznym testem firmy Sigma. Otrzymane wyniki wskazują, iż kontakt ludzkich osteoblastów z powierzchnią poli(ε-kaprolaktonu) powoduje podwyższoną ekspresję genu fosfatazy zasadowej oraz podwyższoną aktywność tego enzymu. Fosfataza zasadowa nie jest specyficznym markerem osteoblastów, jednakże jej podwyższony poziom towarzyszy wczesnym etapom różnicowania w kierunku fenotypu komórek osteogennych. Uzyskane wyniki uzasadniają podjęcie dalszych badań nad możliwym wpływem poli(ε-kaprolaktonu) na różnicowanie osteoblastów.

EN

Poly(ε-caprolactone) is a material used as a scaffold for cells in bone tissue engineering. On the basis of data from literature as well as own research it was concluded that this material can influence the levels of markers of cell differentiation towards osteoblasts. The aim of this paper was to investigate the effect of poly(ε-caprolactone) on the expression and the activity of the early marker of the cell osteogenic differentiation process – alkaline phosphatase (ALP). Using the quantitative real time polymerase chain reaction (real-time PCR) gene expression of the alkaline phosphatase was analyzed; however, the activity of the enzyme was determined with colorimetric assay from the Sigma company. The obtained results indicated that the contact of human osteoblasts with the surface of poly(ε-caprolactone) causes an increased gene expression of alkaline phosphatase and an increased activity of this enzyme. Although a high level of ALP does not prove the PCL influence on the osteogenic differentiation of cells into mature osteoblasts, because this enzyme is a non-specific marker of the differentiation process. The obtained results justify undertaking further studies on the possible impact of poly(ε-caprolactone) on osteoblast differentiation.

15

Proliferacja osteoblastów Saos-2 oraz komórek endotelialnych EA.hy 926 na polerowanych i piaskowanych powierzchniach stopów tytanu Ti6Al4V i Ti6Al7Nb

Walkowiak-Przybyło M., Walczyńska M., Komorowski P., Klimek L., Walkowiak B.

Engineering of Biomaterials

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2011

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Vol. 14, no. 109-111 spec. iss.

39--41

16

Adhesion and growth of human osteoblast-like MG 63 cells on titanium and stainless steel samples developed for constructing bone implants

Stranavova L., Bacakova M., Bacakova L., Fencl J.

Engineering of Biomaterials

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2011

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Vol. 14, no. 109-111 spec. iss.

10--11

EN

Titanium and stainless steel are strong, corrosion - resistant and biocompatible metals. Thanks to their remarkable properties, they have been in use for a long time in clinical medicine, mainly for constructing and replacing large joints, in particular the bone-anchoring parts, e.g. cups and stems, and also for fabricating orthopaedic screws and splints. In the Czech Republic, these devices are produced by Beznoska Ltd., and are clinically applied in the Orthopaedic Clinic, Bulovka Faculty Hospital in Prague. This study has investigated the biocompatibility of samples made of pure titanium (according to quality standard ISO 5832-2 ) and corrosion-resistant steel (quality standards ISO 5832-1 and AISI 316L), obtained from Beznoska. In addition to Fe, the steel samples contained C (max. 0.025 wt. %), Si (0.6 wt. %), Mn (1.7 wt. %), P( max. 0.025 wt. %), S(max. 0.003 wt. %), Cr (17.5 wt. %), Ni (13.5 wt. %), Mo (2.8 wt. %), and Cu (max. 0.1 wt. %). The materials were used in the form of square samples (9x9 mm or 30x30 mm, thickness 1 mm ). Both Ti and steel samples were grinded with SiO2. The surface of the steel samples was then treated by polishing with Al2O3 paste (grain size up to 1 μm), while the surface of the Ti samples, i.e. a material not suitable for polishing, was finished by brushing using another type of Al2O3 paste with slightly larger grains. Thus, the surface of the steel samples was finally smoother and glossy, while the Ti surface was rougher and matted. For the in vitro biocompatibility tests, human osteoblast-like MG 63 cells (European Collection of Cell Cultures, Salisbury, UK) were used. The smaller samples (9 x 9 mm) were inserted into polystyrene 2 4-well cell culture plates (TPP, Trasadingen, Switzerland; well diameter 1.5 cm). Each well contained 25000 cells (approx. 14150 cells / cm 2 ) and 1.5 ml of Dulbecco’s Modified Eagle Minimum Essential Medium (DMEM; Sigma, USA, Cat. No. 10270-106) supplemented with 10 % foetal bovine serum (FBS; Gibco, Cat. No. 10270-106) and gentamicin (40 μg/ml, LEK, Slovenia). These samples were used for evaluating the size of the cell spreading area (day 1), and for evaluating cell shape and cell viability (days 1, 4 and 7 after seeding). The size o f the cell spreading area was measured using Atlas Software (Tescan Ltd., Brno, Czech Republic). The viability of the cells was determined by the LIVE/DEAD viability cytotoxicity kit for mammalian cells (Invitrogen, Molecular Probes, USA). The larger samples (30x30 mm) were inserted into GAMA polystyrene dishes (diameter 5 cm; GAMA Group Joint- Stock Company, Ceske Budejovice, Czech Republic) and seeded with 300000 cells/dish (approx. 15300 cells/cm 2) suspended in 9 ml of the above mentioned culture medium. These samples were used for evaluating the cell number on days 1, 4 and 7 after seeding, using a Beckman Vi- CELL XR Cell Analyser automatic cell counter. The results indicated that the number of initially adhering cells on day 1 after seeding was significantly lower on the titanium (5320±390 cells/cm2) and on the stainless steel ( 4110±370 cells/cm 2) than on the control polystyrene culture dishes (7740±350 cells/cm2). However, on day 4 after seeding, the cell population density on both metallic materials studied here became significantly higher than on the control polystyrene dishes (75200±2 890 cells/cm2 on Ti and 90870 ±2350 cells/cm2 on steel vs. 56440±1180 cells/cm2 on polystrene). This suggests faster cell proliferation on both metallic materials than on polystyrene. At the same time, the cell number on the stainless steel samples was significantly higher than on the Ti samples. On day 7, the differences in number of adhered cells on both studied metals and on the control polystyrene substrate was on an average similar (from 328780±680 cells/cm2 to 362200 ±760 cells/cm2). The cell viability on all tested materials was almost 100 % in all culture intervals. The morphology of the cells on the studied materials was similar to the morphology of the adhered cells on the control polystyrene dishes, i.e. the cells were mostly flat and polygonal, and the size of their cell spreading areas w as similar on all tested materials. The cells were distributed homogeneously on the entire material surface, and on day 4 they started to form confluent cell layers (FIG. (1). It can be concluded that the tests of biocompatibility confirmed that the titanium and the stainless steel promoted the adhesion and growth of bone - derived cells, and thus these materials are promising for construction of bone implants and for their good integration with the surrounding bone tissue. Further studies on osteogenic cell differentiation, potential immune activation and the response of the bone cells to growth factors, including bone morphogenetic protein, are in progress.

17

Porous titanium scaffolds with modified surface: in vitro cell biology assessment

Ścisłowska-Czarnecka A., Menaszek E., Szaraniec B., Chłopek J., Kołaczkowska E.

Engineering of Biomaterials

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2009

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Vol. 12, no. 88

5--10

EN

Interaction of host cells with a biomaterial surface is important for biocompatibility and thus is essential for biomedical applications. Therefore investigations are undertaken to scrutinize for an appropriate surface coating with physical and chemical properties minimizing undesirable activation of immunological response. For this the current study was aimed at examining the effects of different surface modifications of titanium by its coating with ceramic materials - hydroxyapatite, bioglass and CaO-SiO2on osteoblast morphology and secretory activity. Titanium is known for its excellent mechanical properties but its surface has low bioactivity. We report that CaO-SiO2coating decreased a number of attached osteoblasts and altered their morphology. Moreover, the ceramic coatings temporarily upregulated release of pro-inflammatory cytokines IL-6 (all of them) and TNF-α (CaO-SiO2). However, overall the levels of the cytokines were low. In contrast, levels of neutrophil-attracting chemokine IL-8 were the highest. IL-8 was produced mostly by cells incubated with hydroxyapatite titanium coating in contrary to those incubated with either bioglass or CaO-SiO2titanium modifications. In conclusion, the titanium coated with ceramics such as hydroxyapatite or bioglass had the best effect on cell adhesion; however, hydroxyapatite might potentially stimulate destructive neutrophils while CaO-SiO2-coating has a negative effect on cell adhesion.

18

Coating of poly(l-lactide-co-glycolide) scaffolds with collagen/glycosaminoglycan matrices and their effects on osteoblast behaviour

Wojak I., Pamuła E., Dobrzyński P., Zimmermann H., Worch H., Scharnweber D., Hintze V.

Engineering of Biomaterials

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2009

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Vol. 12, no. 86

9-13

EN

Collagen type I and glycosaminoglycans (GAGs) were immobilized on the surfaces of two types of porous biodegradable poly(L-lactide-co-glycolide) (PLGA) scaffolds with pore size in the range of 250-320 µm and 400-600 µm. Two methods of coating were evaluated differing in the way of how the fibrillogenesis solution was introduced into the pores. The distribution of the immunostained collagen in the volume of the scaffolds was analysed with a laser confocal microscope (LSM). The total amount of collagen and GAGs was measured by Sirius Red and Toluidine Blue assays, respectively. The potential of the scaffolds for cell colonization and differentiation was tested in a dynamic cell culture system using human osteosarcoma cells (SAOS-2). The proliferation of SAOS-2 cells was measured by determining the DNA content on days 2 and 7, while differentiation was analyzed by Calcium- and Phosphate-Assays on days 7 and 14. Differentiation of cells was improved by increasing the pore diameter of the scaffolds, and artificial extracellular matrix (aECM) coatings had an additional positive effect for the scaffolds of both pore sizes.

19

Cell attachment on ion implanted titanium surface

Sreejith P. S., Yarlagadda P. K.

Journal of Achievements in Materials and Manufacturing Engineering

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2008

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Vol. 31, nr 2

373-377

EN

Purpose: Of outmost importance for the successful use of an implant is a good adhesion of the surrounding tissue to the biomaterial. In addition to the surface composition of the implant, the surface topography also influences the properties of the adherent cells. In the present investigation, ion implanted and untreated surfaces were compared for cell adhesion and spreading. Design/methodology/approach: The surface topography of the surfaces were analyzed using AFM and the cell studies with SEM. Findings: The results of our present investigation is indicative of the fact that ion implanted titanium surface offer better cell binding affinity compared to untreated/polished surface. Practical implications: Success of non-biodegradable implants will first and foremost depend on biocompatibility, followed by the capacity of the surface topography of the implants to evince desired cell matrix, surface cell matrix interactions. In the present study, the cell growth on ion implanted Ti material is analyzed and discussed. Originality/value: In this paper, we have utilized ion implantation technique, which will produce nano-texturing of the surface without producing any detrimental effects to both the dimensions and properties of the implants.

20

Odpowiedź biologiczna osteoblastów linii Soas-2 inkubowanych na warstwie Ti3P+(Ti-Ni) implantowanej jonami wapnia

Zajączkowska A., Borowski T., Rajchel B., Wierzchoń T., Czarnowska E.

Engineering of Biomaterials

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2008

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Vol. 11, no. 77-80

99--101