Piotr Komorowski

Surface characterization and biological evaluation of silver-incorporated DLC coatings fabricated by hybrid RF PACVD/MS method

Since the biological response of the body towards an implanted material is mainly governed by its surface properties, biomaterials are improved by various kinds of coatings. Their role is to provide good mechanical and biological characteristics, and exclude some disadvantages like post-implantation infections. This phenomenon may be reduced by introduction of silver as an antibacterial agent. This study evaluates the Ag-DLC films synthesized by the hybrid RF PACVD/MS method according to the patent number PL401955-A1 worked out inter alia by the authors. Such tests as XPS, SEM, EDS, AFM, FTIR, Raman and ICP-TOF-MS were used to determine surface properties of the coatings. The obtained results were correlated with the biological response estimated on the basis of cells viability assay (osteoblast cells line Saos-2) and bacterial colonization test (Escherichia coli strain DH5α). Results showed that the hybrid RF PACVD/MS method allows one to get tight coating preventing the diffusion of harmful elements from the metallic substrate. Ag concentration increases with the growing power density, it occurs in metallic state, does not create chemical bonds and is evenly dispersed within the DLC matrix in the form of nanoscale silver clusters. Increasing silver content above 2at.% improves bactericidal properties, but decreases cell viability.

Thermosensitive chitosan gels containing calcium glycerophosphate for bone cell culture

In this article, properties of thermosensitive chitosan hydrogels prepared with the use of chitosan chloride with β-glycerophosphate disodium salt pentahydrate enriched with calcium glycerophosphate are presented and compared with chitosan hydrogels with β-glycerophosphate disodium salt pentahydrate. The study is focused on the determination of hydrogel structure and biological testing of hydrogels with human osteoblasts line Saos-2. The structure of gels was visualized by scanning electron microscopy and was investigated by infrared spectroscopy. The crystallinity of gel structure was determined by X-ray diffraction analysis and thermal effects were determined using differential scanning calorimetry thermograms.

Early cell response to contact with biomaterial's surface

Most biomaterials at present have sufficient mechanical properties; however compliance with standards for biocompatibility is often not sufficient in clinical practice. This may be due to the complexity of biological systems in general and the diversity of individual responses to these materials by implant recipients. Significant improvement of biocompatibility must involve surface modification of implants, which in the future will make it possible to introduce individually selected types of surface modification for individual recipients. The key to this technology seems to be understanding the processes occurring at the site of contact of the implant with the tissue. Processes resulting from the stress generated by the contact of the biomaterial surfaces were observed with endothelial cells line EA.hy926, and it was demonstrated that differently modified surfaces of medical steel (polished medical steel and medical steel coated with Parylene C and nanocrystalline diamond) cause diverse cellular response in cells grown on these surfaces, on both the cellular (cell morphology and cell survival) and molecular (transcriptome and proteome profiles) levels. The herein presented observations are a good starting point not only for further research and the development of far-reaching personalization of medical implants, but also to study the potential use of cells as a specific sensor capable of recognizing different surfaces with which these cells come into contact.

Toxicity of silver nanoparticles, multiwalled carbon nanotubes, and dendrimers assessed with multicellular organism Caenorhabditis elegans

Abstract Nematode Caenorhabditis elegans (C. elegans) was used to investigate the impact of silver nanoparticles (SNP), multiwalled carbon nanotubes (MWCNT), and polyamidoamine dendrimers (PAMAM) used in concentration of 1010 particle/mL. Population-based observations and gene expression analysis were employed in this study. SNP and PAMAM caused decrease in the number of live nematodes and their body length, but MWCNT did not affect the population of nematodes. Gene expression analysis revealed significant changes caused by the presence of all studied nanomaterials, and the results strongly suggest a specific metabolic response of the nematode organism to exposure to various nanomaterials. It was shown that C. elegans is a very sensitive organism capable to respond specifically to the exposure to some nanomaterials and therefore could be considered as a possible biosensor for early warning of presence of some nanoparticles.

Simultaneous transcriptome and proteome analysis of EA.hy926 cells under stress conditions induced by nanomaterials: TRANSCRIPTOME AND PROTEOME ALTERATIONS

Today, the extensive and constantly growing number of applications in the field of nanotechnology poses a lot of questions about the potential toxicity of nanomaterials (NMs) toward cells of different origins. In our work we employed the tools of molecular biology to evaluate changes that occur in human endothelial cells at the transcriptomic and proteomic level, following 24 h of exposure to three different classes of NMs. Using microarray technology, we demonstrated that 24 h of exposure to silver nanoparticles (SNPs), multiwalled carbon nanotubes (MWCNTs) and polyamidoamine dendrimers (PAMAMs) leads to changes in 299, 1271, and 431 genes, respectively, influencing specific molecular pathways. The 2D-DIGE and mass spectrometry analysis revealed that differentially expressed proteins were involved in numerous cellular processes, for example, cytoskeletal reorganization, cell growth and proliferation, or response to stress. Both, transcriptome and proteome alterations indicate reorganization of mechanism regulating cell functioning.

THE USE OF THE FIBROUS CAPSULE SURROUNDING THE SILICONE BREAST IMPLANT AS A CAPSULAR FLAP

Fibrouscapsule surrounding breast prosthesis can be used as a soft tissue flap, which has already been suggested in clinical trials. In the available literature, the potential of using the capsule as a tissue flap has been advocated only on the basis of ultrastructural studies. However, the precise histological design has not been demonstrated, which in turn would have the greatest practical significance. Reliable determination of blood vessels in the fibrouscapsule would show the possibility of utilizing it in plastic surgery as a pedicled flap. The aim of this paper was to demonstrate the ultrastructual and histological properties of the fibrous capsule surrounding the breast prosthesis together with the possibility of clinical application of this structure in plastic surgery. In April 2014, a 54-year-old patient after left-sided mastectomy and breast reconstruction with expander underwent surgical exchange of the expander into prosthesis and right breast reduction. A small section of the fibrous capsule surrounding the expander was meticulously dissected for the scientific purposes. The specimen was examined ultrastructurally and histologically. Ultrastructural study was performed using a scanning electron microscope (SEM). Histological study included staining by Masson, 1 Klinika Chirurgii Onkologicznej i Chorób Piersi Instytutu Centrum Zdrowia Matki Polki w Łodzi 2 Klinika Chirurgii Plastycznej, Rekonstrukcyjnej i Estetycznej Uniwersyteckiego Szpitala Klinicznego Nr 1 w Łodzi 3 Zakład Patomorfologii Instytutu Centrum Zdrowia Matki Polki w Łodzi 4 Laboratorium Biofizyki Molekularnej i Nanostrukturalnej BioNanoPark Łódzkiego Regionalnego Parku Naukowo-Technologicznego PAWEŁ SZYCHTA Klinika Chirurgii Onkologicznej i Chorób Piersi, Instytut Centrum Zdrowia Matki Polki w Łodzi, ul. Rzgowska 281/289, 93-338 Łódź, Tel.: (42) 271 11 01, e-mail: szychta@yahoo.pl Wpłynęło: 08.07.2014 Zaakceptowano: 12.09.2014 DOI: dx.doi.org/10.15374/ChPiO2014016 Artykuł jest dostępny na zasadzie dozwolonego użytku osobistego. Dalsze rozpowszechnianie (w tym umieszczanie w sieci) jest zabronione i stanowi poważne naruszenie przepisów prawa autorskiego oraz grozi sankcjami prawnymi. !