Adherence test medium

The cytotoxicity tests were performed with the use of the direct contact method on the extracts obtained by an 8-d incubation of the polymer PSU and PSU/Ag composite samples, placed at the bottom of the well of a 24-well culture plate, in 2 ml of culture mediiun. The incubation was conducted at 37°C in air atmosphere with a 5% content of C02and 100% of relative air humidity. Next, 0.2 ml of ihe obtained extract and its fourfold dilution in a proper culture medium was dosed for the cultures of human osteoblasts (HTB-85 cell line, ATCC, USA) and human fibroblasts (CRL-7422 cell line, ATCC, USA) adhered to the bottom of the well of a 96-well culture plate. In the case of the control test, the extract of the examined samples was replaced by the proper volume of culture medium. The plates were incubated at 37°C in air atmosphere with a 5% content of CO and 100% of relative air humidity. The incubation time for two parallelly conducted experiments was 24 h and 48 h. The cytotoxicity of PSU and the PSU/Ag composites was measured by 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyltetrazolium (MTT) assay [9, 10] and by lactate dehydrogenase (LDH) activity measured with the use of a commercial cytotoxicity assay kit (Roche Diagnostics GmbH, Mannheim, Germany), [11]. Each of the indications was repeated three times. 

The surface of the sorbent material does not provide good living conditions for microbes. The growth medium adhered to the silica particles in TLC acts a source of nutrients for the test bacteria. 

At large k ( k ) i.e. reversible electron transfer adheres hkewise to the form of (10) thus throughout the current variation depends solely on potential not upon the shape speed of the variation of potential with time. One consequence is that the overlay of Ii as potentials are retraced can be used as a test of adherence to this regime of electron transfer additionally provides for a substance known to exhibit fast electron transfer a simple routine for estimating the uncompensated resistance R. This is carried out, for example, by creating new potential axes via Efrcw=Eoid -i.R with variation of R until overlay is achieved this value then applies to other experiments in the same medium. 

Uniform corrosion in a ceramic takes place as a result of chemical dissolution. The corrosion product formed is nonprotective, being either poorly adherent, soluble, or a good transport medium for the corrodent to the ceramic surface. This is a predictable form of corrosion based on test data or experience. 

Ln vitro studies on HT-29 epithelial cells were made in order to test the capacity of L. johnsonii strains to decrease S. enterica serovar typhimurium UKl-lux invasion (Muller et al., 2011). It was shown that the L. johnsonii proved its exclusion properties just when the probiotic bacteria are growing in minimal medium supplemented with fatty acids. In these conditions, L. johnsonii reduced significantly Salmonella spp. adhesion and invasion. If the L. johnsonii was grown in a medium supplemented with linoleic and linolenic acids, its adhesion was also possible even when the HT-29 cells were infected with Salmonella spp. (Muller et al., 2011). The mechanism proposed in order to explain how probiotics prevent pathogens from infecting cells is that they sterically hinder the adherence of pathogens (Foumiat et al., 1992). 

The effectiveness of such antibiotic-loaded polymers on bacterial adhesion is now being tested under in vitro conditions. In preliminary experiments we have found that flucloxacillin loaded polyurethane leads to a considerable reduction of adhesion in PBS or nutrient-medium in the first 24 hr. Studies with the clindamycin devices revealed that adhesion is not reduced compared to the control polymer, but that a killing effect on adhered bacteria can be seen after 72 hr. We are now studying the incorporation of other antibiotics, with various modes of action, and their effect on bacterial adhesion. 

There are other apodization functions in use besides the Norton-Beer and the Happ-Genzel. These functions have not been tested as thoroughly however, it has been noted by the authors that the Blackman-Harris and Blackman apodization functions (Section 2.4) are considerably broader than the Norton-Beer medium or Happ-Genzel apodization functions. It is expected that these functions will not adhere to Beer s law as well as the Norton-Beer medium function. 

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