Analysis of the tissue harvested around the total hip replacement isolated from re-operated patients in order to: (1) characterize complexity of structural processes developing in the region of the total hip replacement and, (2) to define the role and significance of histological structures of this tissue, mainly in relation to implant loosening, from the viewpoint of formal and causal pathogenesis. MATERIAL AND METHODS Biopsied material isolated from periarticular tissue of re-operated patients (n=19) after THR was analyzed using the methods of light optic, fluorescent (TUNEL), and transmission electron microscopy. RESULTS Histological analysis revealed fibroproliferaive processes and epithelioid granulomatosis cell reaction around the implant with the formation of giant multinuclear syncythial (osteoclastlike) structures as a response to foreign bodies. These structures phagocyte fragments of foreign material (polyethylene particles from the implant, cement fragments). All the used methods revealed a range of regressive changes in the layers of foreign microparticles (inside giant multinuclear cells) typical of fibrinoid necrosis in collagen fibres and apoptosis. In certain cases, progressive changes as chondroid and synovial differentiation (metaplasia) were observed. DISCUSSION Total hip replacement, despite all positive aspects for patients, may cause permanent inflammatory processes in its surrounding. This may result in an extensive fibroproduction of a differently thick layer of connective tissue around the implant. An important factor of loosening of THR is probably osteoclastic resorption in the area of "bone-implant" interface, as a result of the interaction between the inflammatory mechanisms around the implant. CONCLUSION In the postoperative period, there occur fibroproliferative changes in the periarticular tissue and large population of multinuclear cells. In our view, these cells play a role in the production of wear particles from the implant and microparticles of bone tissues and bone cement. Fibroproliferative process may be considered as an immune response to the implanted foreign material.

• MeSH
• granulační tkáň patologie   ultrasonografie   MeSH
• koncové značení zlomů DNA in situ MeSH
• kyčelní kloub patologie   MeSH
• kyčelní protézy MeSH
• lidé středního věku MeSH
• lidé MeSH
• mikroskopie elektronová rastrovací transmisní MeSH
• náhrada kyčelního kloubu MeSH
• reakce na cizí těleso patologie   MeSH
• reoperace MeSH
• selhání protézy MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• ženské pohlaví MeSH

The aim of our study was to test the influence of short exposure (6 h) of preimplantation rabbit embryos to elevated temperatures (41.5 oC or 42.5 oC) in vitro on their developmental capacity. Fertilized eggs recovered from female oviducts at the pronuclear stage (19 hpc) were cultured at standard temperature (37.5 oC) until the morula stage (72 hpc). Afterwards, the embryos were divided into two groups, cultured for 6 h either at hyperthermic (41.5 oC or 42.5 oC) or standard temperature (control 37.5 oC), post-incubated overnight (16-20 h) at 37.5 oC and then evaluated for developmental stages, apoptosis (TUNEL), proliferation (cell number), actin cytoskeleton and presence of heat-shock proteins Hsp70. It was observed that hyperthermia at 41.5 oC did not alter progression of embryos to higher preimplantation stages (expanded and hatching/hatched blastocysts), rate of apoptosis, total cell number of blastocysts and structure of actin filament compared to 37.5 oC. Western-blotting revealed the presence of heat stress-induced 72 kDa fraction of Hsp70 proteins in granulosa cells (exposed to 41 oC) and embryos (exposed to 41.5 oC). Following the elevation of temperature to 42.5 oC embryo development was dramatically compromised. The embryos were arrested at the morula or early blastocyst stage, showed an increased rate of apoptosis and decreased total cell number compared to control. The structure of actin filaments in most of blastomeres was damaged and such blastomeres often contained apoptotic nuclei. In this group a presence of heat-stress-induced fraction of Hsp70 proteins had not been confirmed. This is the first report demonstrating a threshold of thermotolerance of rabbit preimplantation embryos to hyperthermic exposure in vitro. A detrimental effect of higher temperature on the embryo is probably associated with the loss of their ability to produce Hsp70 de novo, which leads to cytoskeleton alterations and enhanced apoptosis.

• MeSH
• aktiny fyziologie   izolace a purifikace   MeSH
• apoptóza genetika   MeSH
• financování organizované využití   MeSH
• indukovaná hypertermie metody   využití   MeSH
• králíci růst a vývoj   MeSH
• proteiny tepelného šoku HSP70 izolace a purifikace   škodlivé účinky   MeSH
• tvorba embrya pro výzkumné účely metody   MeSH
• western blotting metody   využití   MeSH
• Check Tag
• králíci růst a vývoj   MeSH