An increasing interest in the fabrication of implants made of titanium and its alloys results from their capacity to be integrated into the bone system. This integration is facilitated by different modifications of the implant surface. Here, we assessed the bioactivity of amorphous titania nanoporous and nanotubular coatings (TNTs), produced by electrochemical oxidation of Ti6Al4V orthopedic implants' surface. The chemical composition and microstructure of TNT layers was analyzed by X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD). To increase their antimicrobial activity, TNT coatings were enriched with silver nanoparticles (AgNPs) with the chemical vapor deposition (CVD) method and tested against various bacterial and fungal strains for their ability to form a biofilm. The biointegrity and anti-inflammatory properties of these layers were assessed with the use of fibroblast, osteoblast, and macrophage cell lines. To assess and exclude potential genotoxicity issues of the fabricated systems, a mutation reversal test was performed (Ames Assay MPF, OECD TG 471), showing that none of the TNT coatings released mutagenic substances in long-term incubation experiments. The thorough analysis performed in this study indicates that the TNT5 and TNT5/AgNPs coatings (TNT5-the layer obtained upon applying a 5 V potential) present the most suitable physicochemical and biological properties for their potential use in the fabrication of implants for orthopedics. For this reason, their mechanical properties were measured to obtain full system characteristics.

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In vitro measurements oflevels ofultraweak luminescence were carried out using healthy and malignant tissues obtained from 63 patients undergoing surgical operations for cancers of colon, stomach and breast. The results obtained support recent reports that there is a difference in mean intensities of the ultraweak luminescence emitted form healthy and malignant tissues. This work demonstrates, however, that because of a large scatter among the intensities detected for samples obtained from different patients the differences found for the mean intensities cannot serve as a parameter for differentiating between the malignant and normal human tissues.

We report the results offeasibility studies on using digital imaging ofthe laser-induced autofluorescence of colomc tissues for a detection ofpremalignant and malignant lesions ofhuman colon. Images ofthe autofluorescence excited with 325nm line ofHe-Cd laser were recorded in vitro in six regions of a visible spectrum using a CCD camera. A total of 126 areas on 30 tissue specimens was examined. At all the spectral bands selected the intensity of the fluorescence ofthe neoplastic tissues was lower than that of the normal mucosa. The ratio R of the intensities of the autofluorescence of normal and abnormal tissues measured with the 440 nm filter was found to be a sensitive diagnostic parameter for detecting adenocarcinomas. This parameter is less sensitive in detecting adenomatous polyps and does not differentiate polyps with different degrees of dysplasia.