Neuronal-like response of N2a living cells to nanoporous patterns of thin supported anodic alumina.

We report about the response of N2a cells, a mouse neuroblastoma cell line, cultured on inert substrates with controlled porous nanostructure. The substrate surfaces were obtained by anodization and post-fabrication etching of thin aluminum films previously deposited onto glass. The morphology of the adherent cells was assessed by scanning electron microscopy.

Photochromic Polyurethanes Showing a Strong Change of Transparency and Refractive Index.

Photochromic polymers have been studied as rewritable systems for optical elements with tunable transparency in the visible and refractive index in the NIR. Six diarylethene monomers have been synthesized to give thin films of photochromic polyurethanes. The absorption properties of the monomers in solution and of the corresponding polymeric films have been evaluated showing that a transparency contrast in the visible spectrum of the order of 10 3 can be obtained by a suitable choice of the chemical structure and illumination wavelength.

Fabrication of Gold-Coated Ultra-Thin Anodic Porous Alumina Substrates for Augmented SERS.

Anodic porous alumina (APA) is a nanostructured material used as a template in several nanotechnological applications. We propose the use of APA in ultra-thin form (<100 nm) for augmented surface-enhanced Raman scattering (SERS). Here, the effect of in-depth thinning of the APA nanostructures for possible maximization of SERS was addressed.

Multifunctional substrates of thin porous alumina for cell biosensors.

We have fabricated anodic porous alumina from thin films (100/500 nm) of aluminium deposited on technological substrates of silicon/glass, and investigated the feasibility of this material as a surface for the development of analytical biosensors aiming to assess the status of living cells. To this goal, porous alumina surfaces with fixed pitch and variable pore size were analyzed for various functionalities. Gold coated (about 25 nm) alumina revealed surface enhanced Raman scattering increasing with the decrease in wall thickness, with factor up to values of approximately 10(4) with respect to the flat gold surface.

Spectroscopic ellipsometry of self assembled monolayers: interface effects. The case of phenyl selenide SAMs on gold.

This work focuses on the quantitative application of spectroscopic ellipsometry to the study of optical properties and thickness of self assembled monolayers (SAMs) of phenyl selenide deposited from the liquid phase on gold. STM, XPS and cyclic voltammetry measurements provide additional chemical and morphological characterization of the SAMs. While routine ellipsometry analysis of SAMs often relies on the film-induced δΔ change in the Δ ellipsometric angle and discards SAM-substrate interface effects, the present data show a distinctive behaviour of the δΨ data that we assign to interface effects, stronger than those previously found for densely packed alkanethiol SAMs.

Optical properties of Yeast Cytochrome c monolayer on gold: an in situ spectroscopic ellipsometry investigation.

The adsorption of Yeast Cytochrome c (YCC) on well defined, flat gold substrates has been studied by Spectroscopic Ellipsometry (SE) in the 245-1000 nm wavelength range. The investigation has been performed in aqueous ambient at room temperature, focusing on monolayer-thick films. In situ δΨ and δΔ difference spectra have shown reproducibly well-defined features related to molecular optical absorptions typical of the so-called heme group.

Methyl-prednisolone treatment of serum HBsAg negative chronic active hepatitis occurring in transfusion-dependent thalassemia major.

We report the results of a two-year non randomized prednisolone trial carried out in 18 thalassemia major patients with chronic active hepatitis and in 16 controls. We found a beneficial effect on the biochemical remission rate and on the extent of liver inflammation with no significant side effects and no overt reactivation of possible latent HBV infection at three-year follow-up. However, a more prolonged longitudinal study is necessary in order to evaluate whether steroid treatment can impede the evolution to cirrhosis without determining long-term consequences, depending on virus-host interactions such as liver cell carcinoma.

Effect of subcutaneous desferrioxamine on iron balance in young thalassemia major patients.

In this study we evaluated the effect of 1-year, subcutaneous desferrioxamine daily infusion on iron balance in 23 thalassemia major children, aged 8-74 months, with transfusional iron accumulation less than 3.8 g at the outset of the trial. Statistical analysis showed a significant correlation between transfusional iron accumulation and percentage of transfusional iron eliminated.

Iron chelation in transfusion-dependent thalassemia with chronic hepatitis.

In this study maximum urinary iron elimination with continuous desferrioxamine subcutaneous infusion was obtained in thalassemia major patients with chronic persistent or active hepatitis with lower doses (60 mg/kg) than those necessary in patients without hepatitis (80 mg/kg). Since dose-response curves were highly variable the treatment schedule should be tailored to the individual needs of each patient. Both groups may achieve iron balance but chronic hepatitis patients have more frequently a net urinary iron excretion.

Iron overload and desferrioxamine chelation therapy in beta-thalassemia intermedia.

This study on serum ferritin levels in urinary iron excretion after 12h subcutaneous infusion of desferrioxamine in 10 thalassemia intermedia patients shows that even nontransfusion-dependent patients may have positive iron balance resulting in iron overload from 5 years of age. However, the iron overload found in these patients appears to be much lower than in age matched patients with transfusion-dependent thalassemia major. Iron overload increases with advancing age, as shown by increasing serum ferritin levels and desferrioxamine-induced urinary iron elimination.