Significance of Nano- and Microtopography for Cell-Surface Interactions in Orthopaedic Implants

Cell-surface interactions play a crucial role for biomaterial application in orthopaedics. It is evident that not only the chemical composition of solid substances influence cellular adherence, migration, proliferation and differentiation but also the surface topography of a biomaterial. The progressive application of nanostructured surfaces in medicine has gained increasing interest to improve the cytocompatibility and osteointegration of orthopaedic implants. Therefore, the understanding of cell-surface interactions is of major interest for these substances. In this review, we elucidate the principle mechanisms of nano- and microscale cell-surface interactions in vitro for different cell types onto typical orthopaedic biomaterials such as titanium (Ti), cobalt-chrome-molybdenum (CoCrMo) alloys, stainless steel (SS), as well as synthetic polymers (UHMWPE, XLPE, PEEK, PLLA). In addition, effects of nano- and microscaled particles and their significance in orthopaedics were reviewed. The significance for the cytocompatibility of nanobiomaterials is discussed critically

The new HMI beamline MAGS an instrument for hard X ray diffraction at BESSY

The Hahn Meitner Institute Berlin is operating the new hard X ray diffraction beamline MAGS at the Berlin synchrotron radiation source BESSY. The beamline is intended to complement the existing neutron instrumentation at the Berlin Neutron Scattering Centre. The new beamline uses a 7 T multipole wiggler to produce photon fluxes in the 1011 1012 photons s 100 mA 0.1 bandwidth range at energies from 4 to 30 keV at the experiment. It has active bendable optics to provide flexible horizontal and vertical focusing and to compensate the large heat load from the wiggler source. The experimental endstation consists of a six circle Huber diffractometer which can be used with an additional polarization analyser and different sample environments. The beamline is intended for single crystal diffraction and resonant magnetic scattering experiments for the study of ordering phenomena, phase transitions and materials scienc

Spinning around or stagnation - what do osteoblasts and chondroblasts really like?

<p>Abstract</p> <p>Objective</p> <p>The influcence of cytomechanical forces in cellular migration, proliferation and differentation of mesenchymal stem cells (MSCs) is still poorly understood in detail.</p> <p>Methods</p> <p>Human MSCs were isolated and cultivated onto the surface of a 3 × 3 mm porcine collagen I/III carrier. After incubation, cell cultures were transfered to the different cutures systems: regular static tissue flasks (group I), spinner flasks (group II) and rotating wall vessels (group III). Following standard protocols cells were stimulated lineage specific towards the osteogenic and chondrogenic lines. To evaluate the effects of applied cytomechanical forces towards cellular differentiation distinct parameters were measured (morphology, antigen and antigen expression) after a total cultivation period of 21 days in vitro.</p> <p>Results</p> <p>Depending on the cultivation technique we found significant differences in both gen and protein expression.</p> <p>Conclusion</p> <p>Cytomechanical forces with rotational components strongly influence the osteogenic and chondrogenic differentiation.</p

Migration pattern of cementless press fit cups in the presence of stabilizing screws in total hip arthroplasty

The aim of this study was to evaluate the initial acetabular implant stability and late acetabular implant migration in press fit cups combined with screw fixation of the acetabular component in order to answer the question whether screws are necessary for the fixation of the acetabular component in cementless primary total hip arthroplasty. One hundred and seven hips were available for follow-up after primary THA using a cementless, porous-coated acetabular component. A total of 631 standardized radiographs were analyzed digitally by the "single-film-x-ray-analysis" method (EBRA). One hundred 'and one (94.4%) acetabular components did not show significant migration of more than 1 mm. Six (5.6%) implants showed migration of more than 1 mm. Statistical analysis did not reveal preoperative patterns that would identify predictors for future migration. Our findings suggest that the use of screw fixation for cementless porous- coated acetabular components for primary THA does not prevent cup migration

Institutional maintenance of macroeconomic equilibrium and well-being

Goodwill component changes the pricing mechanism and gives the production of knowledge marketable character, complementing its with cognitive component. The paper substantiates the need to institute a regulated competitive market order as the search strategy of social sustainable balance consolidated on the basis of the reproduction cognitive capital process

Earlier age of dementia onset and shorter survival times in dementia patients with diabetes

Diabetes is a risk factor for dementia, but relatively little is known about the epidemiology of the association. A retrospective population study using Western Australian hospital inpatient, mental health outpatient, and death records was used to compare the age at index dementia record (proxy for onset age) and survival outcomes in dementia patients with and without preexisting diabetes (n = 25,006; diabetes, 17.3%). Inpatient records from 1970 determined diabetes history in this study population with incident dementia in years 1990–2005. Dementia onset and death occurred an average 2.2 years and 2.6 years earlier, respectively, in diabetic compared with nondiabetic patients. Age-specific mortality rates were increased in patients with diabetes. In an adjusted proportional hazard model, the death rate was increased with long-duration diabetes, particularly with early age onset dementia. In dementia diagnosed before age 65 years, those with a ≥15-year history of diabetes died almost twice as fast as those without diabetes (hazard ratio = 1.9, 95% confidence interval: 1.3, 2.9). These results suggest that, in patients with diabetes, dementia onset occurs on average 2 years early and survival outcomes are generally poorer. The effect of diabetes on onset, survival, and mortality is greatest when diabetes develops before middle age and after 15 years’ diabetes duration. The impact of diabetes on dementia becomes progressively attenuated in older age groups

Moderate alcohol consumption lowers the risk of type 2 diabetes: a meta-analysis of prospective observational studies

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Meta-analysis of the relationship between alcohol consumption and coronary heart disease and mortality in type 2 diabetic patients

Aims/hypothesis: This systematic review examines the relationship between alcohol consumption and long-term complications of type 2 diabetes. Meta-analyses could only be performed for total mortality, mortality from CHD, and CHD incidence, because the availability of articles on other complications was too limited. Materials and methods: A PubMed search through to September 2005 was performed and the reference lists of relevant articles examined. Among the relevant articles there were six cohort studies reporting on the risk of total mortality and/or fatal and/or incident CHD in alcohol non-consumers and in at least two groups of alcohol consumers. Results: Statistical pooling showed lower risks in alcohol consumers than in non-consumers (the reference category). The relative risk (RR) of total mortality was 0.64 (95% CI 0.49-0.82) in the <6 g/day category. In the higher alcohol consumption categories (6 to <18, and ≥18 g/day), the RRs of total mortality were not significant. Risks of fatal and total CHD were significantly lower in all three categories of alcohol consumers (<6, 6 to <18 and ≥18 g/day) than in non-consumers, with RRs ranging from 0.34 to 0.75. Conclusions/interpretation: This meta-analysis shows that, as with findings in the general population, moderate alcohol consumption is associated with a lower risk of mortality and CHD in type 2 diabetic populations. © Springer-Verlag 2006.