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Our aim was to analyze the expression of the serine protease HtrA1 in human bladder tissue and urine in order to point out its possible association with the presence of urothelial bladder cancer. Bladder tissue and urine specimens from cancer patients with different tumor grades and stages (n 5 68) and from individuals with cystitis (n 5 16) were collected along with biopsy specimens and urine from healthy individuals (n 5 68). For the first time, we demonstrated by immunohistochemistry that HtrA1 protein is produced by bladder urothelium in both physiological and inflammatory conditions, whereas it is not detectable in urothelial cancer cells regardless of tumor grade and stage. A different HtrA1 expression between normal-looking and neoplastic bladder tissue, despite similar HtrA1 mRNA levels, was also found by western blotting, which disclosed the presence of two forms of HtrA1, a native form of~50 kDa and an autocatalytic form of~38 kDa. Our investigations documented the presence of the two forms of HtrA1 also in urine. The~38 kDa form was significantly down-regulated in neoplastic tissue, whereas significantly higher amounts of both HtrA1 forms were found in urine from cancer patients compared with both healthy subjects and patients with cystitis. Our findings suggest that HtrA1 is a downexpressed molecule since an early stage of bladder urothelial carcinoma development and that urinary HtrA1 protein may be considered, if successfully validated, as an early and highly sensitive and specific biomarker for this neoplasia (the sensitivity and specificity of HtrA1 are 92.65% and 95.59%, respectively).

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The pitting corrosion resistance of AISI 444, 304L and 316L stainless steels in two tap waters with different chloride concentrations at 80 8C was studied. Cyclic potentiodynamic polarization (CPP) tests were carried out starting from E corr À 30 mV until the current density reached 0.1 mA/cm 2 (scan rate 0.166 mV/s); the scan was then reversed and continued until new passivity conditions were achieved. The corrosion potential was measured before the polarization experiments. From the E-log i plots, the values of pitting and protection potential were obtained; from these potentials, the perfect and the imperfect passivity regions were defined to compare the corrosion resistance of the studied steels. CPP tests were performed both on as received stainless steel samples and on samples submitted to different cleaning-passivation treatments to improve their corrosion resistance. The results indicate that, for industrial production, AISI 444 stainless steel can substitute the more expensive AISI 304L or 316L after a cleaning-passivation treatment that reduces the presence of inclusions.

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