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1

Comparison of qNANO results from the isolation of extracellular microvesicles with the theoretical model

Durak-Kozica Martyna, Wróbel Andrzej, Platt Mark, Stępień Ewa Ł.

Bio-Algorithms and Med-Systems

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2022

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Vol. 18, no. 1

171--179

EN

Objectives: Extracellular vesicles (EVs) are heterogeneous membrane vesicles in diameter of 30-5000 nm, that transport proteins, non-coding RNAs (miRNAs), lipids and metabolites. Major populations include exosomes, ectosomes and apoptotic bodies. The purpose of this study was to compare the distribution of EVs obtained under different conditions of differential centrifugation, including ultracentrifugation, with the results developed based on a theoretical model. Methods: Immortalized endothelial cell line that expresses h-TERT (human telomerase) was used to release of EVs: microvascular TIME. EVs were isolated from the culture medium at different centrifugation parameters. The size distribution of the EVs was measured using TRPS technology on a qNano instrument. Surface markers were evaluated using flow cytometry. The isolated EV subpopulations were compared with the theoretical model developed by Livshits. Results: EVs isolated from endothelial cells show strong aggregating properties, which was confirmed by TEM, TRPS imaging and flow cytometry. Conclusions: Obtaining pure EV subpopulations is difficult because of the small differences in the diameter of ectosomes and exosomes, and the strong aggregating properties of EVs.

2

Photoactivated titania-based nanomaterials for potential application as cardiovascular stent coatings

Kopaczyńska M., Sobieszczańska B., Ulatowska-Jarża A., Hołowacz I., Buzalewicz I., Wasyluk Ł., Tofail S. A. M., Biały D., Wawrzyńska M., Podbielska H.

Biocybernetics and Biomedical Engineering

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2014

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Vol. 34, no. 3

189--197

EN

Intravascular stenting of atherosclerotic coronary arteries is a life-saving, widely used procedure in interventional cardiology. Adverse clinical outcomes such as restenosis high-light the importance of meeting the excellent biocompatibility by cardiovascular implants. Many attempts have been made to improve the safety profile of implant surface. We for the first time developed the photoactive intravascular titania-based nanomaterials for the application as cardiovascular stent coating. Photoactive biomaterial deposited on the cardiovascular stent surface demonstrated promising features, making it an excellent substrate for endothelial cells growth and proliferation. The biocompatibility of these coatings has been compared with 316L stainless steel surfaces typically used in commercial coronary stents production. The results of the study proved that the innovative titania- based coatings have better biocompatibility characteristics than the 316L stainless steel and in regard of its antithrombotic potential provided protection against restenosis. Further-more, the titania coating supported endothelial cells attachment and proliferation, and induced prolonged plasma recalcification time in comparison with stainless steel surface. Innovative photoactive titania coating can be an important factor to prevent the process of the restenosis in the place of implantation.

3

Otrzymywanie nowoczesnych biomateriałów do kardiochirurgii metodą inżynierii tkankowej

Ziętek P., Butruk B., Ciach T.

Inżynieria i Aparatura Chemiczna

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2013

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Nr 5

504--505

PL

Celem pracy było opracowanie nowatorskiego materiału na bazie poliuretanu pokrytego warstwą ludzkich komórek śródbłonka. Aby upodobnić powierzchnię polimeru do naturalnego środowiska komórek śródbłonka przeprowadzono 3-etapowy proces zakończony trwałym przyłączeniem cząsteczek białka (kolagenu) do powierzchni poliuretanu. Zaproponowana metoda cechuje się prostotą i obiecującą efektywnością. Hodowla komórek śródbłonka wykazała adhezję i wzrost komórek na otrzymanych materiałach

EN

Inż. Ap. Chem. 2013, 52, no. 5,504 The aim of this work was to fabricate a novel material based on polyurethane coated with human endothelial cells. To promote endothelial cells adhesion, the surface of polyurethane was grafted with collagen in a 3-step chemical procedure. The procedure can be characterized as promising and simple. Endothelial cells anchored and proliferated on obtained materials confirmed the effectiveness of the proposed method of collagen grafting.

4

Steady and disturbed flow effects on human umbilical vein endothelial cells (HUVECs) in vascular system: an experimental study

Arslan N., Isik S., Uykan O.

Acta of Bioengineering and Biomechanics

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2010

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Vol. 12, no. 4

3-9

EN

Coronary artery disease is still one of the most important reasons of the death in the world. The endothelium is the membrane of special cells which lines the interior surface of blood vessels forming an interface between circulating blood in the lumen and the rest of the vessel wall. Endothelial cells (ECs) line the entire circulatory system, from the heart to the smallest capillary. ECs dysfunction has been linked with atherosclerosis through their response to fluid forces. ECs change their morphology when exposed to mechanical stresses. The morphological responses include reorientation, elongation, and rearrangement of adhering molecules. Atherosclerotic lesions are formed in specific arterial regions, where low and oscillatory endothelial shear stress (ESS) occur. In this study, the effects of steady and disturbed flow over human umbilical vein endothelial cells (HUVECs) at different flow rates and periods were determined. Steady flow experiments were performed at flow rate of 1000 cm3/min for twenty four hours. Disturbed flow experiments simulating the flow in branching regions of arterial systems were carried out at flow rates of 250 cm3/min for five hours. The results obtained testified to the morphological changes easily observed. The directional alignment of the cells was determined in the steady flow experiments. Under disturbed flow conditions we observed not only the cell movement at the stagnation point but also the polygonal cell shape downstream the flow field.

5

Micro- and nanopatterned surfaces for guided adhesion, growth and phenotypic maturation of cells

Bacakova L., Filova E., Grausova L., Vandrovcova M., Parizek M., Novotna K., Svorcik V., Vacik J., Rypacek F., Kromka A., Heitz J., Shard A.

Engineering of Biomaterials

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2009

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Vol. 12, no. 89-91

18--21

EN

Micropatterned surfaces were created by UV light-irradiation of polytetrafluoroethylene through a metallic mask, by successive plasma polymerization of acrylic acid and 1,7-octadiene, or by creation of prominences and grooves by deposition of fullerenes C60 through a metallic mask. All these surface types were capable of inducing regionally-selective adhesion, proliferation and phenotypic maturation of vascular endothelial cells, vascular smooth muscle cells or human bone-derived MG 63 cells. Nanopatterned surfaces created by tethering GRGDSG oligopeptides through polyethylene oxide chains on a polymeric surface promoted spreading, formation of focal adhesion plaques and DNA synthesis in vascular smooth muscle cells. Surfaces nanopatterned with nanocrystalline diamond gave good support for the adhesion, growth and metabolic activity of osteoblast-like MG 63 cells.

6

Interaction of parylene C with biological objects

Kamińska M., Okrój W., Szymański W., Jakubowski W., Komorowski P., Nosal A., Szymanowski H., Gazicki-Lipman M., Jerczyńska H., Pawłowska Z., Walkowiak B.

Acta of Bioengineering and Biomechanics

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2009

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Vol. 11, nr 3

19-25

EN

The aim of the present work was to examine the interactions of parylene C with such selected biological objects as: blood plasma proteins, platelets, endothelial cells, and bacterial biofilm produced by E. coli cells. The results obtained strongly support the thesis that parylene C is a material worth considering for biomedical use. Parylene C coating on polished medical steel significantly reduces platelet adhesion to this surface. On the other hand, in the case of the surface of machined medical steel coated with parylene C, the number of adhered platelets is significantly higher. This also means that surface texture of substrate material is very well reproduced by parylene C coating and is an important factor facilitating the platelet adhesion. Adsorption of plasma proteins at parylene C surface is very effective, and this finding confirms a notion that cell interaction with surfaces is mediated by the adsorbed proteins. In the light of the above, a high susceptibility of parylene C surface to bacterial colonization is easy to explain. The results showing reduced proliferation and changes in endothelial cell gene expression should also be seriously analysed when parylene C is considered for the use in contact with blood vessels.

7

Endothelial cells on pet vascular prostheses impregnated with polyester-based copolymers and coated with cell-adhesive protein assemblies

Chlupac J., Filova E., Riedel T., Brynda E., Pamuła E., Lisa V., Bacakova L.

Engineering of Biomaterials

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2008

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Vol. 11, no. 81-84

108--111

EN

Arterial bypass surgery with synthetic vascular prostheses achieves poor patency rates compared to autogenous natural materials, and this is a challenge for tissue engineering research concerning small caliber vascular grafts. Modifications of the prosthetic surface followed by endothelial cell seeding may reduce thrombogenicity and intimal hyperplasia. Planar polyethylene terephthalate (PET) vascular prosthetic samples were impregnated with the copolymer poly(glycolide-L-lactide) (PGL) or with the terpolymer poly(glycolide-L-lactide-(e)caprolactone) (PGLCap) in order to lower the permeability of the knitted fabrics and ensure a less adhesive background. Subsequent modification with adhesive protein assemblies composed of collagen type I (Co) in conjunction with laminin (LM), fibronectin (FN) or fibrin (Fb) gel was performed to enhance cell adhesion. Bovine pulmonary artery endothelial cells (EC) of the CPAE line were seeded on to the coatings and subjected to static tissue culture conditions for 7 days. Impregnation of the PET prostheses decreased the initial adhesion and proliferation of the EC. After coating with the protein assemblies, the impregnated PET provided better substrates for cell culture than the protein-coated PET, on which the EC population started decreasing after 4 days of culture. The cells proliferated better on the CoFN, CoFb and CoFbFN coatings than on the Co and CoLM coatings. Impregnation type and adhesive matrix protein deposition may play an important role in successful endothelialization, healing and clinical performance of vascular grafts.

8

Human endothelium on vascular prostheses modified by extracellular matrix proteins in a flow experiment

Chlupac J., Filova E., Riedel T., Brynda E., Remy-Zolghadri M., Bareille R., Fernandez P., Daculsi R., Bordenave L., Bacakova L.

Inżynieria Biomateriałów

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2006

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R. 9, nr 58-60

10-13

EN

Artificial vascular prostheses are used for bypass surgery. Thrombogenicity often cause graft occlusion. Targeted surface alterations including cell seeding may improve the haemocompatibility. Knitted commercial tubular PET (polyethylene terephtalate) vascular prostheses with collagen impregnation were modified by adsorption of laminin (LM) or coating with fibrin network (FB) on the luminal surface. Human endothelial cells were harvested, cultured and seeded at the density of 150x10\3 cells/cm square on all grafts. The cell lining was continuously visualized and quantified. The retention was 21%, 37% and only 2% of the seeding density on the unmodified (UM), LM- and FB-coated grafts, respectively. These seeded prostheses were exposed to a laminar shear stress (SS) 15 dynes/cm square for 40 minutes (UM, LM, FB) and 120 min (UM, LM) in a chamber simulating blood circulation. The SS was excluded in static (ST) control grafts. After 40 min-SS the cell numbers were78%, 27% and 72% for the UM, LM and FB prosthesis compared to the ST. The cell densities were 61% and 57% on the UM and LM after 120 min-SS. To conclude, the endothelium formed a confluent layer whereas laminin immobilization improved endothelial adhesion but not the flow resistance. Reverse effect was observed on fibrin coating.

9

Influence of laminar shear stress on cytoskeleton and ICAM-1 expression of endothelial cells

Muller S., Sun R., Legrand S., Labrador V., Wang X., Stoltz J. F.

Applied Mechanics and Engineering

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1999

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Vol. 4, no spec.

151-156

EN

The aim of this work was to study the morphological behavior and the surface adhesion molecules expression and localization of a human endothelial cell line subjected in vitro to a laminar flow in a parallel plate flow chamber, by a 3-D fluorescence microscopy and cytofluorimetry. At rest, endothelial cells showed an array of microfilament bundles of the actin fibers, and a peripheral distribution of ICAM-1 molecules. After shear stress (1 to 30 dyne/cm2, 1 to 24 hours), the stress fibers appeared and were oriented related to the flow direction but also to the shear. The ICAM-1 expression varied according to the shear stress characteristics and their distribution at the cell surface appeared also modified and related to the stress fibers formation.