Corrosion resistance of ZrTi alloys with hydroxyapatite-zirconia silver layer in simulated physiological solution containing proteins for biomaterial applications

The degradation characteristics of hydroxyapatite-zirconia-silver films (HA-ZrO2-Ag) coatings on three ZrTi alloys were investigated in Ringer’s solution containing 10% human albumin protein at 37 °C. Samples were immersed for 7 days while monitored by electrochemical impedance spectroscopy (EIS) and linear potentiodynamic polarization (LPP). The electrochemical analysis in combination with surface analytical characterization by scanning electron microscopy (SEM/EDX) reveals the stability and corrosion resistance of the HA–ZrO2-Ag coated ZrTi alloys. The characteristic feature that describes the electrochemical behaviour of the coated alloys is the coexistence of large areas of the coating presenting pores in which the ZrTi alloy substrate is exposed to the simulated physiological environment. The EIS interpretation of results was thus performed using a two-layer model of the surface film. The blocking effect in the presence the human albumin protein produces an enhancement of the corrosion resistance. The results disclose that the Zr45Ti alloy is a promising material for biomedical devices, since electrochemical stability is directly associated to biocompatibilit

European objectives in the post-Kyoto period and expectations for Venice

In January 2007, the Environmental Directorate of the European Commission released a preview of the results of a study on climate change and its consequences. Climate changes predicted for the next 20 years are already happening, as demonstrated by the latest scientific investigations, and are accelerating faster than predicted. The main novelty of the European report is that the European Union commits itself to promoting and leading the endeavour to reduce greenhouse gas emissions. EU countries are committed to a 30% autonomous unilateral decrease in emissions by 2020. This ambitious project should be a clear signal to the international community of the leading role Europe intends to play. The increase in temperature has a dramatic effect that will affect people living in coastal areas, and in Italy, the first glance is for the Venice situation. IPCC estimates suggest that increased annual temperatures and an increase in extreme precipitations in the Adriatic Sea will be the likely effects of global climate change. It becomes essential to be able to adapt to climate change and to plan an increase in resilience and a reduction of the costs of environmental damage. It is impossible to predict how climate change will unfold over the next 20-30 years, but it is nevertheless possible to protect our communities from the worst consequences to some extent

PPARα and PPARγ activation is associated with pleural mesothelioma invasion but therapeutic inhibition is ineffective

Mesothelioma is a cancer that typically originates in the pleura of the lungs. It rapidly invades the surrounding tissues, causing pain and shortness of breath. We compared cell lines injected either subcutaneously or intrapleurally and found that only the latter resulted in invasive and rapid growth. Pleural tumours displayed a transcriptional signature consistent with increased activity of nuclear receptors PPARα and PPARγ and with an increased abundance of endogenous PPAR-activating ligands. We found that chemical probe GW6471 is a potent dual PPARα/γ antagonist with anti-invasive and anti-proliferative activity in vitro. However, administration of GW6471 at doses that provided sustained plasma exposure levels sufficient for inhibition of PPARα/γ transcriptional activity did not result in significant anti-mesothelioma activity in mice. Lastly, we demonstrate that the in vitro antitumour effect of GW6471 is off-target. We conclude that dual PPARα/γ antagonism alone is not a viable treatment modality for mesothelioma