Time filter

Source Type

Koscielniak-Ziemniak M.,Medical University of Silesia, Katowice | Koscielniak-Ziemniak M.,Artificial Heart Laboratory | Pilawa B.,Medical University of Silesia, Katowice
Applied Magnetic Resonance | Year: 2013

Thermal formation of free radicals in flumetasone sterilized according to the pharmaceutical norms at 160, 170 and 180 °C was examined by electron paramagnetic resonance (EPR) spectroscopy. The microbiological analysis was done. Similar free radical concentrations were measured for flumetasone sterilized at 160 and 170 °C. The concentration was considerably higher than that for flumetasone sterilized at 180 °C. Fast spin-lattice relaxation processes, homogeneously broadened EPR lines, and complex free radicals system characterize the heated flumetasone. Free radicals were not observed 30 days after thermal sterilization. Optimal temperatures of sterilization of flumetasone are 160 and 170 °C. © 2013 The Author(s). Source

Koscielniak-Ziemniak M.,Medical University of Silesia, Katowice | Koscielniak-Ziemniak M.,Artificial Heart Laboratory | Pilawa B.,Medical University of Silesia, Katowice
Applied Magnetic Resonance | Year: 2012

Paramagnetic centers in the three glucocorticosteroid drugs, such as betamethasone, clobetasol, and dexamethasone, were examined by the use of X-band (9.3 GHz) electron paramagnetic resonance (EPR) spectroscopy. Glucocorticosteroid drugs were sterilized according to the norms at 160 °C (120 min), 170 °C (60 min), and 180 °C (30 min). Free radical properties, types, and concentrations in the individual glucocorticosteroids were compared. The lineshape and parameters of EPR curves recorded in the range of the microwave power of 0.7-70 mW were tested. The non-heated drugs were diamagnetic. Free radicals were formed in clobetasol and dexamethasone drugs during process of their thermal sterilization, while free radicals were not detected in thermally sterilized betamethasone. Fast spin-lattice relaxation processes existed in heated clobetasol and dexamethasone. Their EPR lines were homogeneously broadened. A complex free radical system characterized these two drugs. Optimal conditions of sterilization of glucocorticosteroids were obtained. Betamethasone may be sterilized at 160, 170, and 180 °C. Clobetasol may be sterilized at 160 and 170 °C. Dexamethasone may be sterilized at 170 and 180 °C. © 2012 Springer-Verlag. Source

Gawlikowski M.,Artificial Heart Laboratory | Gawlikowski M.,Silesian University of Technology | Pustelny T.,Silesian University of Technology
BioMedical Engineering Online | Year: 2012

Background: In spite of numerous non-invasive examinations the " gold clinical standard" of cardiac output measurements is the invasive pulmonary artery catheterization by means of the Swan-Ganz catheter and the application of the thermodilution method to estimate the blood flow. The results obtained by means of thermodilution are sensitive to many physical and biological disturbances. The unreliability of this method amounts to 20-45% and depends on the given variant of the method. Therefore some other method, more accurate and resistant to disturbances, was looked for. This paper presents a new approach to cardiac output measurements, based on cross-correlation signal analysis. The goal of investigations was to verify experimentally the application of the cross-correlation method of cardiac output measurements.Results: In 99.2% of the examined cases the extreme of the cross-correlation function was easy to be estimated by numerical algorithms. In 0,8% of the remaining cases (with a plateau region adjacent to the maximum point) numerical detection of the extreme was inaccurate. The typical unreliability of the investigated method amounted o 5.1% (9.8% in the worst case). Investigations performed on a physical model revealed that the unreliability of cardiac output measurements by means of the cross-correlation method is 3-5 times better than in the case of thermodilution.Conclusions: The performed investigations and theoretical analysis have shown, that the cross-correlation method may be applied in cardiac output measurements. This kind of measurements seems to be more accurate and disturbance-resistant than clinically applied thermodilution. © 2012 Gawlikowski and Pustelny; licensee BioMed Central Ltd. Source

Gonsior M.,Artificial Heart Laboratory | Kustosz R.,Artificial Heart Laboratory | Koscielniak-Ziemniak M.,Artificial Heart Laboratory | Wierzchon T.,Warsaw University of Technology
Archives of Metallurgy and Materials | Year: 2015

The innovative extracorporeal heart support device ReligaHeart (RH EXT) has been developed, based on POLVAD ventricular assist device clinical experience, collected in more than 300 patient applications. The innovative surface engineering technologies are applied in ReligaHeart EXT device. The pump is manufactured of new generation, modified surface structure, biocompatible polyurethanes, and equipped with original tilting disc valves, Moll type. The valve ring is made of titanium alloy, TiN+Ti2N+αTi(N) diffusive layer modified, produced with glow discharge at plasma potential, in order to obtain the lowest thrombogenicity. The valve disc is made of polyether ether ketone. The complex in vitro and in vivo biological evaluations were performed, confirming both biomaterials biocompatible properties and device biocompatibility, proved in 30 days animal heart support. Source

Butruk-Raszeja B.A.,Warsaw University of Technology | Lojszczyk I.,Warsaw University of Technology | Ciach T.,Warsaw University of Technology | Koscielniak-Ziemniak M.,Artificial Heart Laboratory | And 3 more authors.
Colloids and Surfaces B: Biointerfaces | Year: 2015

In the article the authors present hydrogel coatings prepared from polyvinylpyrrolidone (PVP) macromolecules, which are chemically bonded to polyurethane (PU) substrate. The coating is designed to improve the surface hemocompatibility of blood-contacting medical devices.The coating was characterized in terms of physical properties (swelling ratio, hydrogel density, surface morphology, coating thickness, coating durability). In order to examine surface hemocompatibility, the materials were contacted with whole human blood under arterial flow simulated conditions followed by calculation of platelet consumption and the number of platelet aggregates. Samples were also contacted with platelet-poor plasma; the number of surface-adsorbed fibrinogen molecules was measured using ELISA assay. Finally, the inflammatory reaction after implantation was assessed, using New Zealand rabbits.The designed coating is characterized by high water content and excellent durability in aqueous environment - over a 35-day period, no significant changes in coating thickness were observed. Experiments with blood proved twice the reduction in adsorption of serum-derived fibrinogen together with a moderate reduction in the number of platelet aggregates formed during the contact of the material with blood. The analysis of an inflammatory reaction after the implantation confirmed high biocompatibility of the fabricated materials - studies have shown no toxic effects of the implanted material on the surrounding animal tissues. © 2015 Elsevier B.V. Source

Discover hidden collaborations