ABSTRACT
PrLuO3 interlanthanides were prepared at temperatures ranging from 800 °C to 1600 °C using hydrothermally-derived precursors. The chemical reactions observed include the conversion and segregation of Pr(OH)3 and LuO(OH), respectively, into PrO2 and Lu2O3 cubic oxides below 1200 °C, followed by the production of a mixture of hexagonal P63/mmc and orthorhombic Pnma PrLuO3 phases at 1400 °C. Phase-pure orthorhombic PrLuO3 was obtained at 1600 °C, which was corroborated by Raman and micro far-infrared spectroscopic analyses. Photoluminescence, colorimetric and lifetime measurements were carried out in PrLuO3 samples. Dominant emission verified in samples calcined at 1400 °C corresponds to the hypersensitive 3P0 â 3F2 transition with a color purity of 97% (decay times of 12 µs and 3 µs), while emissions for the phase-pure samples correspond to the 3P0 â 3H6 and 3P0 â 3H5 transitions with a color purity of 94% (a single luminescence lifetime of 12 µs). The optical properties of PrLuO3 interlanthanides thereby suggest that they can be used as luminescent materials in both structural arrangements.
ABSTRACT
BACKGROUND: Autoimmune hepatitis (AIH) is a disease that presents itself in various forms, ranging from aminotransferase asymptomatic alteration, acute hepatitis to decompensated cirrhosis. Few studies have evaluated the predictive criteria as a response to treatment. METHODS: A cross-sectional analytical study examined patients with AIH who were visited in the hepatology clinic of a university hospital between January 2013 and July 2015. RESULTS: A total of 36 patients were included (44.7 ± 14.3 years, 22.2% male, and 19.2% of patients presented with liver failure). Patients with significant fibrosis had lower mean aminotransferases and bilirubins and higher mean prothrombin activity (PA) than those with insignificant fibrosis. Most patients (94.5%) underwent treatment with azathioprine and prednisone. In a comparison between individuals who exhibited biochemical response (ALT and AST < 55 U/L in the sixth month of treatment) and those without biochemical response, it was observed that those with biochemical response presented minor proportion of patients with significant fibrosis, and these patients had a higher proportion of liver failure in initial presentation and lower mean PA. Furthermore, it was observed that the lower the PT on admission was, the lower ALT levels (r = 0.682, P = 0.020) and AST (r = 0.431, P = 0.040) in the sixth month of treatment were. CONCLUSIONS: Individuals with liver dysfunction and elevated aminotransferases show insignificant fibrosis histologically. AIH patients who initially present liver failure and insignificant fibrosis are more likely to develop biochemical response to treatment.
