Nano-Ag Particles Embedded in C-Matrix: Preparation, Properties and Application in Cell Metabolism.

The application of nano-Ag grains as antiviral and antibacterial materials is widely known since ancient times. The problem is the toxicity of the bulk or big-size grain materials. It is known that nano-sized silver grains affect human and animal cells in some medical treatments. The aim of this study is to investigate the influence of nano-Ag grains embedded in a carbonaceous matrix on cytotoxicity, genotoxicity in fibroblasts, and mutagenicity. The nanocomposite film is composed of silver nanograins embedded in a carbonaceous matrix and it was obtained via the PVD method by deposition from two separated sources of fullerenes and silver acetate powders. This method allows for the preparation of material in the form of a film or powder, in which Ag nanograins are stabilized by a carbon network. The structure and morphology of this material were studied using SEM/EDX, XRD, and Raman spectroscopy. The toxicology studies were performed for various types of the material differing in the size of Ag nanograins. Furthermore, it was found that these properties, such as cell viability, genotoxicity, and mutagenicity, depend on Ag grain size.

[Significance of primary stabilization of the acetabular part of hip endoprosthesis in revision arthroplasty with extensive bone defects]. / Znaczenie pierwotnej stabilizacji panewki endoprotezy przy rozleglych ubytkach w artroplastykach rewizyjnych biodra.

In this article author discuss medium term results of first or next secondary replacement of acetabular part of hip endoprosthesis--after filling up cavernous or segmental bone defects. There were analysed 104 operated hips 70 (67.3%) female and 34 (32.7%) male. Bilateral hip arthroplasty (in two sessions) was performed in 14 women and 5 men. The average age was 69.8 years. The mean time between the primary arthroplasty and the revision was 12.1 years. The follow up was 2-15 years, mean 5.4 years. Cemented acetabulum was used in 71 revisions (68.3%), self-threaded in 19 (18.3%) and pressed in 14 (13.5%). Destabilization and migration of acetabular part of prosthesis appeared in 14 events (13.5%). Radiolucency local zones on X-ray referred to possible pseudomembrane round the acetabular part without clinical manifestations were shown in 19 cases (18.3%). The study demonstrated that migration of acetabular part of hip prosthesis due to secondary stabilisation deficiency took place in hips were proper primary stabilisation was not achieved because of extensive bone defects.