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Majerčíková M, Nádaždy P, Chorvát D, Satrapinskyy L, Valentová H, Kroneková Z, Šiffalovič P, Kronek J, Zahoranová A. Effect of Dexamethasone on Thermoresponsive Behavior of Poly(2-Oxazoline) Diblock Copolymers. Polymers (Basel) 2021; 13:polym13091357. [PMID: 33919321 PMCID: PMC8122420 DOI: 10.3390/polym13091357] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 04/13/2021] [Accepted: 04/17/2021] [Indexed: 01/22/2023] Open
Abstract
Thermoresponsive polymers play an important role in designing drug delivery systems for biomedical applications. In this contribution, the effect of encapsulated hydrophobic drug dexamethasone on thermoresponsive behavior of diblock copolymers was studied. A small series of diblock copoly(2-oxazoline)s was prepared by combining thermoresponsive 2-n-propyl-2-oxazoline (nPrOx) and hydrophilic 2-methyl-2-oxazoline (MeOx) in two ratios and two polymer chain lengths. The addition of dexamethasone affected the thermoresponsive behavior of one of the copolymers, nPrOx20-MeOx180, in the aqueous medium by shifting the cloud point temperature to lower values. In addition, the formation of microparticles containing dexamethasone was observed during the heating of the samples. The morphology and number of microparticles were affected by the structure and concentration of copolymer, the drug concentration, and the temperature. The crystalline nature of formed microparticles was confirmed by polarized light microscopy, confocal Raman microscopy, and wide-angle X-ray scattering. The results demonstrate the importance of studying drug/polymer interactions for the future development of thermoresponsive drug carriers.
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Affiliation(s)
- Monika Majerčíková
- Department for Biomaterials Research, Polymer Institute of the Slovak Academy of Sciences, Dúbravská cesta 9, 845 41 Bratislava, Slovakia; (M.M.); (Z.K.)
| | - Peter Nádaždy
- Institute of Physics of the Slovak Academy of Sciences, Dúbravská cesta 9, 845 11 Bratislava, Slovakia; (P.N.); (P.Š.)
| | - Dušan Chorvát
- International Laser Centre, Department of Biophotonics, Ilkovičova 3, 841 04 Bratislava, Slovakia;
| | - Leonid Satrapinskyy
- Department of Experimental Physics, Faculty of Mathematics, Physics and Informatics, Comenius University, Mlynská Dolina, 842 48 Bratislava, Slovakia;
| | - Helena Valentová
- Faculty of Mathematics and Physics, Charles University, Ke Karlovu 3, 121 16 Prague 2, Czech Republic;
| | - Zuzana Kroneková
- Department for Biomaterials Research, Polymer Institute of the Slovak Academy of Sciences, Dúbravská cesta 9, 845 41 Bratislava, Slovakia; (M.M.); (Z.K.)
| | - Peter Šiffalovič
- Institute of Physics of the Slovak Academy of Sciences, Dúbravská cesta 9, 845 11 Bratislava, Slovakia; (P.N.); (P.Š.)
- Centre for Advanced Materials Application, Slovak Academy of Sciences, Dúbravská cesta 9, 845 11 Bratislava, Slovakia
| | - Juraj Kronek
- Department for Biomaterials Research, Polymer Institute of the Slovak Academy of Sciences, Dúbravská cesta 9, 845 41 Bratislava, Slovakia; (M.M.); (Z.K.)
- Correspondence: (J.K.); (A.Z.)
| | - Anna Zahoranová
- Institute of Applied Synthetic Chemistry, Vienna University of Technology, Getreidemarkt 9/163MC, A-1060 Vienna, Austria
- Correspondence: (J.K.); (A.Z.)
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2
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Trel'ová D, Salgarella AR, Ricotti L, Giudetti G, Cutrone A, Šrámková P, Zahoranová A, Chorvát D, Haško D, Canale C, Micera S, Kronek J, Menciassi A, Lacík I. Soft Hydrogel Zwitterionic Coatings Minimize Fibroblast and Macrophage Adhesion on Polyimide Substrates. Langmuir 2019; 35:1085-1099. [PMID: 29792034 DOI: 10.1021/acs.langmuir.8b00765] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Minimizing the foreign body reaction to polyimide-based implanted devices plays a pivotal role in several biomedical applications. In this work, we propose materials exhibiting nonbiofouling properties and a Young's modulus reflecting that of soft human tissues. We describe the synthesis, characterization, and in vitro validation of poly(carboxybetaine) hydrogel coatings covalently attached to polyimide substrates via a photolabile 4-azidophenyl group, incorporated in poly(carboxybetaine) chains at two concentrations of 1.6 and 3.1 mol %. The presence of coatings was confirmed by attenuated total reflectance Fourier transform infrared spectroscopy. White light interferometry was used to evaluate the coating continuity and thickness (between 3 and 6 μm under dry conditions). Confocal laser scanning microscopy allowed us to quantify the thickness of the swollen hydrogel coatings that ranged between 13 and 32 μm. The different hydrogel formulations resulted in stiffness values ranging from 2 to 19 kPa and led to different fibroblast and macrophage responses in vitro. Both cell types showed a minimum adhesion on the softest hydrogel type. In addition, both the overall macrophage activation and cytotoxicity were observed to be negligible for all of the tested material formulations. These results are a promising starting point toward future advanced implantable systems. In particular, such technology paves the way for novel neural interfaces able to minimize the fibrotic reaction, once implanted in vivo, and to maximize their long-term stability and functionality.
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Affiliation(s)
- Dušana Trel'ová
- Department for Biomaterials Research , Polymer Institute of the Slovak Academy of Sciences , Dúbravská cesta 9 , 845 41 Bratislava , Slovakia
| | - Alice Rita Salgarella
- The BioRobotics Institute, Scuola Superiore Sant'Anna , Viale R. Piaggio 34 , 56025 Pontedera ( PI ), Italy
| | - Leonardo Ricotti
- The BioRobotics Institute, Scuola Superiore Sant'Anna , Viale R. Piaggio 34 , 56025 Pontedera ( PI ), Italy
| | - Guido Giudetti
- The BioRobotics Institute, Scuola Superiore Sant'Anna , Viale R. Piaggio 34 , 56025 Pontedera ( PI ), Italy
| | - Annarita Cutrone
- The BioRobotics Institute, Scuola Superiore Sant'Anna , Viale R. Piaggio 34 , 56025 Pontedera ( PI ), Italy
- SMANIA srl, via G. Volpe 12 , 56121 Pisa , Italy
| | - Petra Šrámková
- Department for Biomaterials Research , Polymer Institute of the Slovak Academy of Sciences , Dúbravská cesta 9 , 845 41 Bratislava , Slovakia
| | - Anna Zahoranová
- Department for Biomaterials Research , Polymer Institute of the Slovak Academy of Sciences , Dúbravská cesta 9 , 845 41 Bratislava , Slovakia
| | - Dušan Chorvát
- International Laser Centre , Ilkovičova 3 , Bratislava 841 04 , Slovak Republic
| | - Daniel Haško
- International Laser Centre , Ilkovičova 3 , Bratislava 841 04 , Slovak Republic
| | - Claudio Canale
- Department of Physics , University of Genova , Via dodecaneso 33 , 16133 Genova , Italy
- Department of Nanophysics , Istituto Italiano di Tecnologia (IIT) , Via Morego 30 , 16163 Genova , Italy
| | - Silvestro Micera
- The BioRobotics Institute, Scuola Superiore Sant'Anna , Viale R. Piaggio 34 , 56025 Pontedera ( PI ), Italy
- Bertarelli Foundation Chair in Translational Neuroengineering, Center for Neuroprosthetics and Institute of Bioengineering , Ecole Polytechnique Federale de Lausanne , 1015 , Lausanne , Switzerland
| | - Juraj Kronek
- Department for Biomaterials Research , Polymer Institute of the Slovak Academy of Sciences , Dúbravská cesta 9 , 845 41 Bratislava , Slovakia
| | - Arianna Menciassi
- The BioRobotics Institute, Scuola Superiore Sant'Anna , Viale R. Piaggio 34 , 56025 Pontedera ( PI ), Italy
| | - Igor Lacík
- Department for Biomaterials Research , Polymer Institute of the Slovak Academy of Sciences , Dúbravská cesta 9 , 845 41 Bratislava , Slovakia
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3
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Datta S, Jutková A, Šrámková P, Lenkavská L, Huntošová V, Chorvát D, Miškovský P, Jancura D, Kronek J. Unravelling the Excellent Chemical Stability and Bioavailability of Solvent Responsive Curcumin-Loaded 2-Ethyl-2-oxazoline-grad-2-(4-dodecyloxyphenyl)-2-oxazoline Copolymer Nanoparticles for Drug Delivery. Biomacromolecules 2018; 19:2459-2471. [PMID: 29634248 DOI: 10.1021/acs.biomac.8b00057] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
A new gradient copolymer has been synthesized by the living cationic ring-opening polymerization of hydrophilic 2-ethyl-2-oxazoline with lipophilic 2-(4-dodecyloxyphenyl)-2-oxazoline (EtOx-grad-DPOx). The prepared copolymer is capable of assembling in water to yield polymeric nanoparticles that are successfully loaded with an anticancer agent, curcumin. Self-assembly of the copolymer was found to be tuned by the polarity as well as the hydrogen bonding ability of solvents. Solvent took distinctive role in the preparation of unloaded and curcumin-loaded nanoparticles. The stability of the nanoparticles was increased by curcumin loading promoted by curcumin-polymer interactions. Further, the chemical stability of curcumin in water is largely enhanced inside the polymeric nanoparticles. Curcumin-loaded (EtOx-grad-DPOx) copolymer nanoparticles showed excellent stability in the biological medium, low cytotoxicity, and concentration dependent uptake by U87 MG and HeLa cells, which indicate the possibility of their efficient application in drug delivery.
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Affiliation(s)
- Shubhashis Datta
- Center for Interdisciplinary Biosciences , Technology and Innovation Park, P. J. Šafárik University in Košice , Jesenná 5 , 041 54 Košice , Slovak Republic
| | - Annamária Jutková
- Department of Biophysics, Faculty of Science , P. J. Šafárik University in Košice , Jesenná 5 , 041 54 Košice , Slovak Republic
| | - Petra Šrámková
- Department for Biomaterials Research , Polymer Institute of the Slovak Academy of Sciences , Dúbravská cesta 9 , 845 41 Bratislava , Slovak Republic
| | - Lenka Lenkavská
- Department of Biophysics, Faculty of Science , P. J. Šafárik University in Košice , Jesenná 5 , 041 54 Košice , Slovak Republic
| | - Veronika Huntošová
- Center for Interdisciplinary Biosciences , Technology and Innovation Park, P. J. Šafárik University in Košice , Jesenná 5 , 041 54 Košice , Slovak Republic
| | - Dušan Chorvát
- Laboratory of Laser Microscopy and Spectroscopy , International Laser Centre , Il'kovičova 3 , 841 04 Bratislava 4 , Slovak Republic
| | - Pavol Miškovský
- Center for Interdisciplinary Biosciences , Technology and Innovation Park, P. J. Šafárik University in Košice , Jesenná 5 , 041 54 Košice , Slovak Republic.,Department of Biophysics, Faculty of Science , P. J. Šafárik University in Košice , Jesenná 5 , 041 54 Košice , Slovak Republic
| | - Daniel Jancura
- Center for Interdisciplinary Biosciences , Technology and Innovation Park, P. J. Šafárik University in Košice , Jesenná 5 , 041 54 Košice , Slovak Republic.,Department of Biophysics, Faculty of Science , P. J. Šafárik University in Košice , Jesenná 5 , 041 54 Košice , Slovak Republic
| | - Juraj Kronek
- Department for Biomaterials Research , Polymer Institute of the Slovak Academy of Sciences , Dúbravská cesta 9 , 845 41 Bratislava , Slovak Republic
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4
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Kroneková Z, Pelach M, Mazancová P, Uhelská L, Treľová D, Rázga F, Némethová V, Szalai S, Chorvát D, McGarrigle JJ, Omami M, Isa D, Ghani S, Majková E, Oberholzer J, Raus V, Šiffalovič P, Lacík I. Structural changes in alginate-based microspheres exposed to in vivo environment as revealed by confocal Raman microscopy. Sci Rep 2018; 8:1637. [PMID: 29374272 PMCID: PMC5785987 DOI: 10.1038/s41598-018-20022-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Accepted: 01/11/2018] [Indexed: 12/20/2022] Open
Abstract
A next-generation cure for type 1 diabetes relies on immunoprotection of insulin-producing cells, which can be achieved by their encapsulation in microspheres made of non-covalently crosslinked hydrogels. Treatment success is directly related to the microsphere structure that is characterized by the localization of the polymers constituting the hydrogel material. However, due to the lack of a suitable analytical method, it is presently unknown how the microsphere structure changes in vivo, which complicates evaluation of different encapsulation approaches. Here, confocal Raman microscopy (CRM) imaging was tailored to serve as a powerful new tool for tracking structural changes in two major encapsulation designs, alginate-based microbeads and multi-component microcapsules. CRM analyses before implantation and after explantation from a mouse model revealed complete loss of the original heterogeneous structure in the alginate microbeads, making the intentionally high initial heterogeneity a questionable design choice. On the other hand, the structural heterogeneity was conserved in the microcapsules, which indicates that this design will better retain its immunoprotective properties in vivo. In another application, CRM was used for quantitative mapping of the alginate concentration throughout the microbead volume. Such data provide invaluable information about the microenvironment cells would encounter upon their encapsulation in alginate microbeads.
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Affiliation(s)
- Zuzana Kroneková
- Department for Biomaterials Research, Polymer Institute of the Slovak Academy of Sciences, Dúbravská cesta 9, 845 41, Bratislava, Slovakia
| | - Michal Pelach
- Department of Multilayers and Nanostructures, Institute of Physics of the Slovak Academy of Sciences, Dúbravská cesta 9, 845 11, Bratislava, Slovakia
| | - Petra Mazancová
- Department for Biomaterials Research, Polymer Institute of the Slovak Academy of Sciences, Dúbravská cesta 9, 845 41, Bratislava, Slovakia
| | - Lucia Uhelská
- Department for Biomaterials Research, Polymer Institute of the Slovak Academy of Sciences, Dúbravská cesta 9, 845 41, Bratislava, Slovakia
| | - Dušana Treľová
- Department for Biomaterials Research, Polymer Institute of the Slovak Academy of Sciences, Dúbravská cesta 9, 845 41, Bratislava, Slovakia
| | - Filip Rázga
- Department for Biomaterials Research, Polymer Institute of the Slovak Academy of Sciences, Dúbravská cesta 9, 845 41, Bratislava, Slovakia
| | - Veronika Némethová
- Department for Biomaterials Research, Polymer Institute of the Slovak Academy of Sciences, Dúbravská cesta 9, 845 41, Bratislava, Slovakia
| | - Szabolcs Szalai
- Department for Biomaterials Research, Polymer Institute of the Slovak Academy of Sciences, Dúbravská cesta 9, 845 41, Bratislava, Slovakia
| | - Dušan Chorvát
- Department of Biophotonics, International Laser Center, Ilkovicova 3, 841 04, Bratislava, Slovakia
| | - James J McGarrigle
- Division of Transplantation, Department of Surgery, University of Illinois at Chicago, 840 South Wood Street, Chicago, Illinois, 60612, USA
| | - Mustafa Omami
- Division of Transplantation, Department of Surgery, University of Illinois at Chicago, 840 South Wood Street, Chicago, Illinois, 60612, USA
| | - Douglas Isa
- Division of Transplantation, Department of Surgery, University of Illinois at Chicago, 840 South Wood Street, Chicago, Illinois, 60612, USA
| | - Sofia Ghani
- Division of Transplantation, Department of Surgery, University of Illinois at Chicago, 840 South Wood Street, Chicago, Illinois, 60612, USA
| | - Eva Majková
- Department of Multilayers and Nanostructures, Institute of Physics of the Slovak Academy of Sciences, Dúbravská cesta 9, 845 11, Bratislava, Slovakia
| | - José Oberholzer
- Division of Transplantation, Department of Surgery, University of Illinois at Chicago, 840 South Wood Street, Chicago, Illinois, 60612, USA
| | - Vladimír Raus
- Department for Biomaterials Research, Polymer Institute of the Slovak Academy of Sciences, Dúbravská cesta 9, 845 41, Bratislava, Slovakia.,Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, Heyrovsky Sq. 2, 162 06, Prague 6, Czech Republic
| | - Peter Šiffalovič
- Department of Multilayers and Nanostructures, Institute of Physics of the Slovak Academy of Sciences, Dúbravská cesta 9, 845 11, Bratislava, Slovakia
| | - Igor Lacík
- Department for Biomaterials Research, Polymer Institute of the Slovak Academy of Sciences, Dúbravská cesta 9, 845 41, Bratislava, Slovakia.
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5
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Kroneková Z, Mikulec M, Petrenčíková N, Paulovičová E, Paulovičová L, Jančinová V, Nosál' R, Reddy PS, Shimoga GD, Chorvát D, Kronek J. Ex Vivo and In Vitro Studies on the Cytotoxicity and Immunomodulative Properties of Poly(2-isopropenyl-2-oxazoline) as a New Type of Biomedical Polymer. Macromol Biosci 2016; 16:1200-11. [DOI: 10.1002/mabi.201600016] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2016] [Revised: 04/01/2016] [Indexed: 11/07/2022]
Affiliation(s)
- Zuzana Kroneková
- Department for Biomaterials Research; Polymer Institute; Slovak Academy of Sciences; Dubravska cesta 9 845 41 Bratislava Slovakia
| | - Marcel Mikulec
- Department for Biomaterials Research; Polymer Institute; Slovak Academy of Sciences; Dubravska cesta 9 845 41 Bratislava Slovakia
| | - Nadežda Petrenčíková
- Department for Biomaterials Research; Polymer Institute; Slovak Academy of Sciences; Dubravska cesta 9 845 41 Bratislava Slovakia
| | - Ema Paulovičová
- Institute of Chemistry; Center of Glycomics; Slovak Academy of Sciences; Dubravska cesta 9 84236 Bratislava Slovakia
| | - Lucia Paulovičová
- Institute of Chemistry; Center of Glycomics; Slovak Academy of Sciences; Dubravska cesta 9 84236 Bratislava Slovakia
| | - Viera Jančinová
- Institute of Experimental Pharmacology & Toxicology; Slovak Academy of Sciences; Dubravska cesta 9 841 04 Bratislava Slovakia
| | - Radomír Nosál'
- Institute of Experimental Pharmacology & Toxicology; Slovak Academy of Sciences; Dubravska cesta 9 841 04 Bratislava Slovakia
| | - Palem S. Reddy
- Centre of Polymer Systems; University Institute; Tomas Bata University in Zlin; Trˇída T. Bati 5678; Zlin 760 01 Czech Republic
| | - Ganesh D. Shimoga
- Centre of Polymer Systems; University Institute; Tomas Bata University in Zlin; Trˇída T. Bati 5678; Zlin 760 01 Czech Republic
| | - Dušan Chorvát
- International Laser Centre; Ilkovičova 3 841 04 Bratislava Slovakia
| | - Juraj Kronek
- Department for Biomaterials Research; Polymer Institute; Slovak Academy of Sciences; Dubravska cesta 9 845 41 Bratislava Slovakia
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Kasák P, Mosnáček J, Danko M, Krupa I, Hloušková G, Chorvát D, Koukaki M, Karamanou S, Economou A, Lacík I. A polysulfobetaine hydrogel for immobilization of a glucose-binding protein. RSC Adv 2016. [DOI: 10.1039/c6ra14423c] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
A hydrogel based on sulfobetaine methacrylate monomer and crosslinker was investigated as a potential material for fluorescent glucose biosensor applications.
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Affiliation(s)
- Peter Kasák
- Center for Advanced Materials
- Qatar University
- 2713 Doha
- Qatar
| | - Jaroslav Mosnáček
- Polymer Institute of the Slovak Academy of Sciences
- 845 41 Bratislava
- Slovakia
| | - Martin Danko
- Polymer Institute of the Slovak Academy of Sciences
- 845 41 Bratislava
- Slovakia
| | - Igor Krupa
- Center for Advanced Materials
- Qatar University
- 2713 Doha
- Qatar
| | - Gabriela Hloušková
- Polymer Institute of the Slovak Academy of Sciences
- 845 41 Bratislava
- Slovakia
| | | | | | - Spyridoula Karamanou
- KU Leuven
- Department of Microbiology and Immunology
- Rega Institute for Medical Research
- Laboratory of Molecular Bacteriology
- B-3000 Leuven
| | | | - Igor Lacík
- Polymer Institute of the Slovak Academy of Sciences
- 845 41 Bratislava
- Slovakia
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7
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Zahoranová A, Kroneková Z, Zahoran M, Chorvát D, Janigová I, Kronek J. Poly(2-oxazoline) hydrogels crosslinked with aliphatic bis(2-oxazoline)s: Properties, cytotoxicity, and cell cultivation. ACTA ACUST UNITED AC 2015. [DOI: 10.1002/pola.28009] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Anna Zahoranová
- Polymer Institute of the Slovak Academy of Sciences; Dúbravská Cesta 9, 845 41 Bratislava Slovakia
| | - Zuzana Kroneková
- Polymer Institute of the Slovak Academy of Sciences; Dúbravská Cesta 9, 845 41 Bratislava Slovakia
| | - Miroslav Zahoran
- Department of Experimental Physics, Faculty of Mathematics, Physics and Informatics; Comenius University; Mlynská Dolina, 842 48 Bratislava Slovakia
| | - Dušan Chorvát
- International Laser Center; Ilkovičova 3, 841 04 Bratislava Slovakia
| | - Ivica Janigová
- Polymer Institute of the Slovak Academy of Sciences; Dúbravská Cesta 9, 845 41 Bratislava Slovakia
| | - Juraj Kronek
- Polymer Institute of the Slovak Academy of Sciences; Dúbravská Cesta 9, 845 41 Bratislava Slovakia
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Bertóková A, Vikartovská A, Bučko M, Gemeiner P, Tkáč J, Chorvát D, Štefuca V, Neděla V. Biooxidation of 2-phenylethanol to phenylacetic acid by whole-cellGluconobacter oxydansbiocatalyst immobilized in polyelectrolyte complex capsules. BIOCATAL BIOTRANSFOR 2015. [DOI: 10.3109/10242422.2015.1053470] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Uhelská L, Chorvát D, Hutchinson RA, Santanakrishnan S, Buback M, Lacík I. Radical Propagation Kinetics of N-Vinylpyrrolidone in Organic Solvents Studied by Pulsed-Laser Polymerization-Size-Exclusion Chromatography (PLP-SEC). MACROMOL CHEM PHYS 2015. [DOI: 10.1002/macp.201400592] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Lucia Uhelská
- Polymer Institute of the Slovak Academy of Sciences; Dúbravská cesta 9 845 41 Bratislava Slovakia
| | - Dušan Chorvát
- International laser centre; Ilkovičova 3 841 04 Bratislava Slovakia
| | - Robin A. Hutchinson
- Department of Chemical Engineering, Dupuis Hall; Queen's University; Kingston Ontario K7L 3N6 Canada
| | - Sandhya Santanakrishnan
- Department of Chemical Engineering, Dupuis Hall; Queen's University; Kingston Ontario K7L 3N6 Canada
| | - Michael Buback
- Institute of Physical Chemistry, University of Goettingen; Tammannstraße 6 37077 Goettingen Germany
| | - Igor Lacík
- Polymer Institute of the Slovak Academy of Sciences; Dúbravská cesta 9 845 41 Bratislava Slovakia
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10
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Uhelská L, Chorvát D, Hutchinson RA, Santanakrishnan S, Buback M, Lacík I. Radical Propagation Kinetics ofN-Vinylpyrrolidone in Organic Solvents Studied by Pulsed-Laser Polymerization-Size-Exclusion Chromatography (PLP-SEC). MACROMOL CHEM PHYS 2014. [DOI: 10.1002/macp.201400329] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Lucia Uhelská
- Polymer Institute of the Slovak Academy of Sciences; Dúbravská cesta 9 845 41 Bratislava Slovakia
| | - Dušan Chorvát
- International laser centre; Ilkovicˇova 3 841 04 Bratislava Slovakia
| | - Robin A. Hutchinson
- Department of Chemical Engineering; Dupuis Hall, Queen's University; Kingston Ontario K7L 3N6 Canada
| | - Sandhya Santanakrishnan
- Department of Chemical Engineering; Dupuis Hall, Queen's University; Kingston Ontario K7L 3N6 Canada
| | - Michael Buback
- Institute of Physical Chemistry; University of Goettingen; Tammannstraße 6 37077 Goettingen Germany
| | - Igor Lacík
- Polymer Institute of the Slovak Academy of Sciences; Dúbravská cesta 9 845 41 Bratislava Slovakia
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11
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Kolecka A, Chorvát D, Bujdáková H. The impact of growth conditions on biofilm formation and the cell surface hydrophobicity in fluconazole susceptible and tolerant Candida albicans. Folia Microbiol (Praha) 2014; 60:45-51. [DOI: 10.1007/s12223-014-0338-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Accepted: 07/16/2014] [Indexed: 10/24/2022]
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12
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Čavarga I, Bilčík B, Výboh P, Záškvarová M, Chorvát D, Kasák P, Mlkvý P, Mateašík A, Chorvátová A, Miškovský P. Photodynamic effect of hypericin after topical application in the ex ovo quail chorioallantoic membrane model. Planta Med 2014; 80:56-62. [PMID: 24414308 DOI: 10.1055/s-0033-1360174] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Photosensitizing properties of hypericin are well known, and the chicken chorioallantoic membrane has previously been used to test photodynamic effects of hypericin and other substances. In our study the photodynamic effect of hypericin in the ex ovo quail chorioallantoic membrane model was evaluated. Steady-state and time-resolved fluorescence spectroscopy of hypericin solution in PEG-400 and its mixture in PBS was performed to assess and characterize the process of aggregation and disaggregation of hypericin during the drug formulation preparation. A therapeutical formulation (2 µg/g of embryo weight) was topically applied on CAM into the silicone ring. Hypericin was excited by diode laser with wavelength 405 nm, fluence rate 140 mW/cm2, and fluence 16.8 J/cm2. Hypericin in 100% PEG-400 exhibits typical fluorescence spectra with a maximum of about 600 nm, while hypericin 10% PEG-400 formulation exhibits almost no fluorescence. Time resolved spectra analysis showed fluorescence decay of hypericin in 100% PEG-400 solution with a mean lifetime of 5.1 ns and in 10% PEG 4.1 ns. Damage of quail chorioallantoic membrane vasculature after photodynamic therapy ranged from hemorrhage and vanishing of capillary vessels to thrombosis, lysis, and hemorrhage of larger vessels.The presented findings suggest that quail embryos can be used as a suitable model to test the effect of hypericin and other photodynamic compounds.
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Affiliation(s)
- Ivan Čavarga
- Institute of Animal Biochemistry and Genetics, Slovak Academy of Sciences, Ivanka pri Dunaji, Slovakia
| | - Boris Bilčík
- Institute of Animal Biochemistry and Genetics, Slovak Academy of Sciences, Ivanka pri Dunaji, Slovakia
| | - Pavel Výboh
- Institute of Animal Biochemistry and Genetics, Slovak Academy of Sciences, Ivanka pri Dunaji, Slovakia
| | - Monika Záškvarová
- Institute of Animal Biochemistry and Genetics, Slovak Academy of Sciences, Ivanka pri Dunaji, Slovakia
| | | | - Peter Kasák
- Polymer Institute, Slovak Academy of Sciences, Bratislava, Slovakia
| | - Peter Mlkvý
- St Elizabeth Oncological Institute, Bratislava, Slovakia
| | | | | | - Pavol Miškovský
- Dept. of Biophysics, Faculty of Sciences, P. J. Šafárik University, Košice, Slovakia
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Ilčíková M, Mrlík M, Sedláček T, Chorvát D, Krupa I, Šlouf M, Koynov K, Mosnáček J. Viscoelastic and photo-actuation studies of composites based on polystyrene-grafted carbon nanotubes and styrene-b-isoprene-b-styrene block copolymer. POLYMER 2014. [DOI: 10.1016/j.polymer.2013.11.031] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Vršanský P, Chorvát D. Luminescent system of Lucihormetica luckae supported by fluorescence lifetime imaging. Naturwissenschaften 2013; 100:1099-101. [PMID: 24189980 DOI: 10.1007/s00114-013-1100-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2013] [Revised: 09/10/2013] [Accepted: 09/14/2013] [Indexed: 11/30/2022]
Affiliation(s)
- Peter Vršanský
- Geological Institute, Slovak Academy of Sciences, Dubravská cesta 9, P.O. Box 106, 840 05, Bratislava, Slovakia,
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15
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Qi M, Mørch Y, Lacík I, Formo K, Marchese E, Wang Y, Danielson KK, Kinzer K, Wang S, Barbaro B, Kolláriková G, Chorvát D, Hunkeler D, Skjåk-Braek G, Oberholzer J, Strand BL. Survival of human islets in microbeads containing high guluronic acid alginate crosslinked with Ca2+ and Ba2+. Xenotransplantation 2013. [PMID: 23198731 DOI: 10.1111/xen.12009] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND The main hurdles to the widespread use of islet transplantation for the treatment of type 1 diabetes continue to be the insufficient number of appropriate donors and the need for immunosuppression. Microencapsulation has been proposed as a means to protect transplanted islets from the host's immune system. METHODS This study investigated the function of human pancreatic islets encapsulated in Ca(2+) /Ba(2+) -alginate microbeads intraperitoneally transplanted in diabetic Balb/c mice. RESULTS All mice transplanted with encapsulated human islets (n = 29), at a quantity of 3000 islet equivalent (IEQ), achieved normoglycemia 1 day after transplantation and retained normoglycemia for extended periods of time (mean graft survival 134 ± 17 days). In comparison, diabetic Balb/c mice transplanted with an equal amount of non-encapsulated human islets rejected the islets within 2 to 7 days after transplantation (n = 5). Microbeads retrieved after 232 days (n = 3) were found with little to no fibrotic overgrowth and contained viable insulin-positive islets. Immunofluorescent staining on the retrieved microbeads showed F4/80-positive macrophages and alpha smooth muscle actin-positive fibroblasts but no CD3-positive T lymphocytes. CONCLUSIONS The Ca(2+) /Ba(2+) -alginate microbeads can protect human islets from xenogeneic rejection in immunocompetent mice without immunosuppression. However, grafts ultimately failed likely secondary to a macrophage-mediated foreign body reaction.
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Affiliation(s)
- Meirigeng Qi
- Department of Transplant/Surgery, University of Illinois at Chicago, Chicago, IL 60612, USA
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Talafová K, Hrabárová E, Chorvát D, Nahálka J. Bacterial inclusion bodies as potential synthetic devices for pathogen recognition and a therapeutic substance release. Microb Cell Fact 2013; 12:16. [PMID: 23391325 PMCID: PMC3614425 DOI: 10.1186/1475-2859-12-16] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2012] [Accepted: 01/31/2013] [Indexed: 01/19/2023] Open
Abstract
Background Adhesins of pathogens recognise the glycans on the host cell and mediate adherence. They are also crucial for determining the tissue preferences of pathogens. Currently, glyco-nanomaterials provide potential tool for antimicrobial therapy. We demonstrate that properly glyco-tailored inclusion bodies can specifically bind pathogen adhesins and release therapeutic substances. Results In this paper, we describe the preparation of tailored inclusion bodies via the conjugation of indicator protein aggregated to form inclusion bodies with soluble proteins. Whereas the indicator protein represents a remedy, the soluble proteins play a role in pathogen recognition. For conjugation, glutaraldehyde was used as linker. The treatment of conjugates with polar lysine, which was used to inactivate the residual glutaraldehyde, inhibited unwanted hydrophobic interactions between inclusion bodies. The tailored inclusion bodies specifically interacted with the SabA adhesin from Helicobacter pylori aggregated to form inclusion bodies that were bound to the sialic acids decorating the surface of human erythrocytes. We also tested the release of indicator proteins from the inclusion bodies using sortase A and Ssp DNAB intein self-cleaving modules, respectively. Sortase A released proteins in a relatively short period of time, whereas the intein cleavage took several weeks. Conclusions The tailored inclusion bodies are promising “nanopills” for biomedical applications. They are able to specifically target the pathogen, while a self-cleaving module releases a soluble remedy. Various self-cleaving modules can be enabled to achieve the diverse pace of remedy release.
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Affiliation(s)
- Klaudia Talafová
- Institute of Chemistry, Centre for Glycomics, Slovak Academy of Sciences, Dúbravská cesta 9, Bratislava, SK, 84538, Slovak Republic
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Vršanský P, Chorvát D, Fritzsche I, Hain M, Ševčík R. Light-mimicking cockroaches indicate Tertiary origin of recent terrestrial luminescence. Naturwissenschaften 2012; 99:739-49. [DOI: 10.1007/s00114-012-0956-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2012] [Revised: 07/18/2012] [Accepted: 07/20/2012] [Indexed: 10/28/2022]
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Papajová E, Bujdoš M, Chorvát D, Stach M, Lacík I. Method for preparation of planar alginate hydrogels by external gelling using an aerosol of gelling solution. Carbohydr Polym 2012; 90:472-82. [PMID: 24751067 DOI: 10.1016/j.carbpol.2012.05.067] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2012] [Revised: 04/15/2012] [Accepted: 05/19/2012] [Indexed: 01/15/2023]
Abstract
Preparation of planar alginate hydrogels by external gelling requires slow rate of exposure of alginate solution to gelling ions to control gelling process and hydrogel properties. We tackled this issue by exposing solution of sodium alginate to solution of CaCl2 applied as aerosol at exposure rate of 7.5 mg cm(-2) s(-1). Gelling conditions varied with respect to concentrations of sodium alginate (1-3 wt.%) and CaCl2 (0.5-4 wt.%), exposure time (2.5-40 min), the 2nd gelling step in the presence of barium ions, and the storage step. Dimensional stability and Young's modulus values were the principal determined quantities to examine the correlation between hydrogel properties and gelling protocol. The content of calcium ions in hydrogel after gelling by CaCl2 aerosol reveals that the maximum binding capacity of calcium ions by alginate chains was reached. Obtained data suggest that an unusual gelling mechanism related to exposure of sodium alginate to aerosol of gelling solution does not need to be considered since the properties of planar alginate hydrogels follow the trends relevant to general knowledge about alginate hydrogels.
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Affiliation(s)
- Eva Papajová
- Department for Biomaterials Research, Polymer Institute of the Slovak Academy of Sciences, Dúbravská cesta 9, 845 41 Bratislava, Slovakia
| | - Marek Bujdoš
- Comenius University in Bratislava, Faculty of Natural Sciences, Institute of Laboratory Research on Geomaterials, Mlynská dolina 1, 842 15 Bratislava, Slovakia
| | - Dušan Chorvát
- International Laser Center, Ilkovičova 3, 841 04 Bratislava, Slovakia
| | - Marek Stach
- Department for Biomaterials Research, Polymer Institute of the Slovak Academy of Sciences, Dúbravská cesta 9, 845 41 Bratislava, Slovakia
| | - Igor Lacík
- Department for Biomaterials Research, Polymer Institute of the Slovak Academy of Sciences, Dúbravská cesta 9, 845 41 Bratislava, Slovakia
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Schenkmayerová A, Bučko M, Gemeiner P, Chorvát D, Lacík I. Viability of free and encapsulated Escherichia coli overexpressing cyclopentanone monooxygenase monitored during model Baeyer–Villiger biooxidation by confocal laser scanning microscopy. Biotechnol Lett 2011; 34:309-14. [DOI: 10.1007/s10529-011-0765-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2011] [Accepted: 09/26/2011] [Indexed: 11/30/2022]
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Strohhöfer C, Förster T, Chorvát D, Kasák P, Lacík I, Koukaki M, Karamanou S, Economou A. Quantitative analysis of energy transfer between fluorescent proteins in CFP–GBP–YFP and its response to Ca2+. Phys Chem Chem Phys 2011; 13:17852-63. [DOI: 10.1039/c1cp21088b] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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22
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Stach M, Lacík I, Kasák P, Chorvát D, Saunders AJ, Santanakrishnan S, Hutchinson RA. Free-Radical Propagation Kinetics of N
-Vinyl Formamide in Aqueous Solution Studied by PLP-SEC. MACROMOL CHEM PHYS 2010. [DOI: 10.1002/macp.200900545] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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23
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Bujdáková H, Paulovičová E, Borecká-Melkusová S, Gašperík J, Kucharíková S, Kolecka A, Lell C, Jensen DB, Würzner R, Chorvát D, Pichová I. Antibody response to the 45 kDa Candida albicans antigen in an animal model and potential role of the antigen in adherence. J Med Microbiol 2009; 57:1466-1472. [PMID: 19018015 DOI: 10.1099/jmm.0.2008/001479-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The Candida antigen CR3-RP (complement receptor 3-related protein) is supposed to be a 'mimicry' protein because of its ability to bind antibody directed against the alpha subunit of the mammalian CR3 (CD11b/CD18). This study aimed to (i) investigate the specific humoral isotypic response to immunization with CR3-RP in vivo in a rabbit animal model, and (ii) determine the role of CR3-RP in the adherence of Candida albicans in vitro using the model systems of buccal epithelial cells (BECs) and biofilm formation. The synthetic C. albicans peptide DINGGGATLPQ corresponding to 11 amino-acids of the CR3-RP sequence DINGGGATLPQALXQITGVIT, determined by N-terminal sequencing, was used for immunization of rabbits to obtain polyclonal anti-CR3-PR serum and for subsequent characterization of the humoral isotypic response of rabbits. A significant increase of IgG, IgA and IgM anti-CR3-RP specific antibodies was observed after the third (P<0.01) and the fourth (P<0.001) immunization doses. The elevation of IgA levels suggested peptide immunomodulation of the IgA1 subclass, presumably in coincidence with Candida epithelial adherence. Blocking CR3-RP with polyclonal anti-CR3-RP serum reduced the ability of Candida to adhere to BECs, in comparison with the control, by up to 35 % (P<0.001), and reduced biofilm formation by 28 % (P<0.001), including changes in biofilm thickness and integrity detected by confocal laser scanning microscopy. These properties of CR3-RP suggest that it has potential for future vaccine development.
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Affiliation(s)
- Helena Bujdáková
- Department of Microbiology and Virology, Faculty of Natural Sciences, Comenius University, Bratislava, Slovakia
| | - Ema Paulovičová
- Institute of Chemistry, Slovak Academy of Sciences, Bratislava, Slovakia
| | - Silvia Borecká-Melkusová
- Department of Microbiology and Virology, Faculty of Natural Sciences, Comenius University, Bratislava, Slovakia
| | - Juraj Gašperík
- Institute of Molecular Biology, Slovak Academy of Sciences, Bratislava, Slovakia
| | - Soňa Kucharíková
- Department of Microbiology and Virology, Faculty of Natural Sciences, Comenius University, Bratislava, Slovakia
| | - Anna Kolecka
- Department of Microbiology and Virology, Faculty of Natural Sciences, Comenius University, Bratislava, Slovakia
| | - Claudia Lell
- Department of Hygiene, Microbiology and Social Medicine, Innsbruck Medical University, Austria
| | - Dorthe B Jensen
- Department of Hygiene, Microbiology and Social Medicine, Innsbruck Medical University, Austria
| | - Reinhard Würzner
- Department of Hygiene, Microbiology and Social Medicine, Innsbruck Medical University, Austria
| | - Dušan Chorvát
- Department of Biophotonics, International Laser Centre, Bratislava, Slovakia
| | - Iva Pichová
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Prague, Czech Republic
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Stach M, Lacík I, Chorvát D, Buback M, Hesse P, Hutchinson RA, Tang L. Propagation Rate Coefficient for Radical Polymerization of N-Vinyl Pyrrolidone in Aqueous Solution Obtained by PLP−SEC. Macromolecules 2008. [DOI: 10.1021/ma800354h] [Citation(s) in RCA: 91] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Marek Stach
- Polymer Institute of the Slovak Academy of Sciences, Dúbravská cesta 9, 842 36 Bratislava, Slovak Republic; International Laser Center, Ilkovičova 3, 812 19 Bratislava, Slovak Republic; Institut für Physikalische Chemie, Georg-August-Universität Göttingen, Tammannstrasse 6, D-37077, Göttingen, Germany; and Department of Chemical Engineering, Queen’s University, Kingston ON K7L 3N6, Canada
| | - Igor Lacík
- Polymer Institute of the Slovak Academy of Sciences, Dúbravská cesta 9, 842 36 Bratislava, Slovak Republic; International Laser Center, Ilkovičova 3, 812 19 Bratislava, Slovak Republic; Institut für Physikalische Chemie, Georg-August-Universität Göttingen, Tammannstrasse 6, D-37077, Göttingen, Germany; and Department of Chemical Engineering, Queen’s University, Kingston ON K7L 3N6, Canada
| | - Dušan Chorvát
- Polymer Institute of the Slovak Academy of Sciences, Dúbravská cesta 9, 842 36 Bratislava, Slovak Republic; International Laser Center, Ilkovičova 3, 812 19 Bratislava, Slovak Republic; Institut für Physikalische Chemie, Georg-August-Universität Göttingen, Tammannstrasse 6, D-37077, Göttingen, Germany; and Department of Chemical Engineering, Queen’s University, Kingston ON K7L 3N6, Canada
| | - Michael Buback
- Polymer Institute of the Slovak Academy of Sciences, Dúbravská cesta 9, 842 36 Bratislava, Slovak Republic; International Laser Center, Ilkovičova 3, 812 19 Bratislava, Slovak Republic; Institut für Physikalische Chemie, Georg-August-Universität Göttingen, Tammannstrasse 6, D-37077, Göttingen, Germany; and Department of Chemical Engineering, Queen’s University, Kingston ON K7L 3N6, Canada
| | - Pascal Hesse
- Polymer Institute of the Slovak Academy of Sciences, Dúbravská cesta 9, 842 36 Bratislava, Slovak Republic; International Laser Center, Ilkovičova 3, 812 19 Bratislava, Slovak Republic; Institut für Physikalische Chemie, Georg-August-Universität Göttingen, Tammannstrasse 6, D-37077, Göttingen, Germany; and Department of Chemical Engineering, Queen’s University, Kingston ON K7L 3N6, Canada
| | - Robin A. Hutchinson
- Polymer Institute of the Slovak Academy of Sciences, Dúbravská cesta 9, 842 36 Bratislava, Slovak Republic; International Laser Center, Ilkovičova 3, 812 19 Bratislava, Slovak Republic; Institut für Physikalische Chemie, Georg-August-Universität Göttingen, Tammannstrasse 6, D-37077, Göttingen, Germany; and Department of Chemical Engineering, Queen’s University, Kingston ON K7L 3N6, Canada
| | - Lina Tang
- Polymer Institute of the Slovak Academy of Sciences, Dúbravská cesta 9, 842 36 Bratislava, Slovak Republic; International Laser Center, Ilkovičova 3, 812 19 Bratislava, Slovak Republic; Institut für Physikalische Chemie, Georg-August-Universität Göttingen, Tammannstrasse 6, D-37077, Göttingen, Germany; and Department of Chemical Engineering, Queen’s University, Kingston ON K7L 3N6, Canada
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Orečná M, Hafko R, Bačová Z, Podskočová J, Chorvát D, Štrbák V. Different secretory response of pancreatic islets and insulin secreting cell lines INS-1 and INS-1E to osmotic stimuli. Physiol Res 2007; 57:935-945. [PMID: 18052676 DOI: 10.33549/physiolres.931346] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Objective of this study was to characterize osmotically-induced insulin secretion in two tumor cell lines. We compared response of freshly isolated rat pancreatic islets and INS-1 and INS-1E tumor cell lines to high glucose, 30 % hypotonic medium and 20 % hypertonic medium. In Ca(2+)-containing medium glucose induced insulin release in all three cell types. Hypotonicity induced insulin secretion from islets and INS-1 cells but not from INS-1E cells, in which secretion was inhibited despite similar increase in cell volume in both cell types. GdCl(3) (100 micromol/l) did not affect insulin response from INS-1E cells to hypotonic challenge. Hypertonic medium inhibited glucose-induced insulin secretion from islets but not from tumor cells. Noradrenaline (1 micromol/l) inhibited glucose-induced but not swelling-induced insulin secretion from INS-1 cells. Surprisingly, perifusion with Ca(2+)-depleted medium showed distinct secretory response of INS-1E cells to hypotonicity while that of INS-1 cells was partially inhibited. Functioning glucose-induced insulin secretion is not sufficient prerequisite for hypotonicity-induced response in INS-1E cells suggesting that swelling-induced exocytosis is not essential step in the mechanism mediating glucose-induced insulin secretion. Both cell lines are resistant to inhibitory effect of hyperosmolarity on glucose-induced insulin secretion. Response of INS-1E cells to hypotonicity is inhibited by the presence of Ca(2+) in medium.
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Affiliation(s)
- M Orečná
- Institute of Experimental Endocrinology, Center of Excellence of the Slovak Academy of Sciences, Bratislava, Slovakia
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Polohová V, Šnejdárková M, Podskočová J, Svobodová L, Chorvát D, Hianik T. Effect of Voltage on the Topography of Alkanethiol and Poly(amidoamine) Dendrimer Layers with Immobilized Glucose Oxidase. An Atomic Force Microscopy Study. ELECTROANAL 2007. [DOI: 10.1002/elan.200603736] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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27
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Bachárová L, Mateásik A, Chorvát D. [Three-dimensional presentation of the electrocardiogram: new possibilities in comparative studies using cardiologic imaging methods]. Vnitr Lek 2002; 48 Suppl 1:178-82. [PMID: 12744042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/02/2023]
Abstract
The aim of the study was to demonstrate a biomathematical model for the topographic presentation of orthogonal electrocardiogram DECARTO, to present the possibilities for visualisation and processing of ECG in relation to others cardiological imaging methods. In DECARTO (Dipolar ElectroCARdioTOpography), the orthogonal ECG is used as an input signal, the signal is processed by the means of a biomathematical model and presented as areas of activated points on a spherical surface closely surrounding the heart, so-called decartograms. Decartograms can be visualised using the projection of the spherical image surface onto geometrically defined planar or 3D surfaces. The selection of the surface depends on the purpose of ECG imaging, on the evaluation of advantages and limitation of the particular possibilities, such as the degree of deformation, and their comparability with other imaging methods. Another possibility of 3D visualisation of decartograms is the utilisation of time as a 3rd dimension of the space. Additionally to analytically defined geometrical surfaces, it is possible to project decartograms onto a real surface of the heart, constructed from data of other image techniques. In this paper we present a superposition of decartogram and SPECT imaging, which combines graphic presentation of two diagnostic methods providing different but complementary information on the heart. The combination of comparable information allows to study the relationship between electrogenesis and perfusion of myocardium and its metabolism, to study diagnostic and prognostic importance of both agreements and disagreements of used methods. The fusion of information on the structure and function of the heart could potentially increase the diagnostic power of both methods.
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Affiliation(s)
- L Bachárová
- Medzinárodné laserové centrum, Bratislava, Slovenská Republika
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Polák J, Kvasnicka P, Chorvát D, Kállay Z. Model of distribution of anticancer agents transplanted into the brain tissue using the random walk method. Gen Physiol Biophys 1992; 11:459-68. [PMID: 1291447] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
A Monte-Carlo approach to analysis of dispersion in the tissue of a locally administered drug is presented. The distribution of a drug in the tissue is simulated as a distribution of randomly walking particles. The approach is demonstrated on a simple situation for which both experimental results and an analytical solution are known. The approach can be used in situations, where common numeric methods are difficult to use, especially for analyses of drug transport in an inhomogeneous space, and problems with complex boundary conditions, e.g. in analyses of dispersion of anticancer agents locally applied into tumours.
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Affiliation(s)
- J Polák
- Institute of Preventive and Clinical Medicine, Bratislava, Czecho-Slovakia
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29
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Brozman M, Ondrus B, Chorvát D, Jakubovský J, Zaviacic M, Janík P. [The scientific and technical development of pathology at the Institute of Pathology at Comenius University Medical School and the Medical Hospital in Bratislava. I. Computer documentation, clinicopathologic analysis of the causes of death, new methods in histologic practice]. BRATISL MED J 1987; 87:184-93. [PMID: 3555714] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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Hianik T, Miklovicová J, Bajci A, Chorvát D, Sajter V. Calcium-induced changes in oxidized cholesterol bilayers. Gen Physiol Biophys 1984; 3:79-84. [PMID: 6745638] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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31
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Miklovicová J, Sajter V, Hianik T, Chorvát D. [Mechanical properties of biological membranes]. BRATISL MED J 1983; 80:653-60. [PMID: 6661675] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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Trnovec T, Plesková A, Chorvát D. The effect of carbon tetrachloride on radiocerium metabolism in rats. Strahlentherapie 1974; 147:521-30. [PMID: 4416181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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Trnovec T, Plesková A, Vladár M, Chorvát D. The effect of colloidal carbon on radiocerium metabolism in rats. Strahlentherapie 1972; 143:570-5. [PMID: 5055955] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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Plesková A, Trnovec T, Chorvát D, Vladár M. The effect of colloidal iron hydroxide on radiocerium metabolism in rats and mice. Strahlentherapie 1971; 142:480-5. [PMID: 5125968] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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Trnovec T, Plesková A, Chorvát D, Vladár M. The effect of glucan on radiocerium metabolism in rats. Strahlentherapie 1971; 142:353-9. [PMID: 5118505] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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Chorvát D, Kollár J, Trnovec T, Plesková A. [Computer program for the determination of gamma emmitter activity in biological samples]. BRATISL MED J 1970; 54:173-84. [PMID: 5474160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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