Synthesis of azafluoranthenes by iridium-catalyzed [2 + 2 + 2] cycloaddition and evaluation of their fluorescence properties.

We report a method for the synthesis of azafluoranthenes under neutral reaction conditions in a highly atom-economical manner by the iridium-catalyzed [2 + 2 + 2] cycloaddition of 1,8-dialkynylnaphthalenes with nitriles. A variety of nitriles react with methyl- or phenyl-substituted 1,8-dialkynylnaphthalenes to give a wide range of azafluoranthenes. Azafluoranthenes bearing an amino group show intense fluorescence at around 500 nm. Comparison of the fluorescence properties of amine-substituted azafluoranthenes with related compounds revealed the importance of the amine moiety for obtaining a high fluorescence quantum yield. The choice of the solvent affected the emission maxima and the fluorescence quantum yield. Azafluoranthenes bearing pyrrolidine exhibited blue-shifted emission bands in a non-polar solvent and gave a fluorescence quantum yield of 0.76 in toluene. A Lippert-Mataga plot and computational studies provide insight into the origin of the fluorescence of azafluoranthenes. Furthermore, cellular experiments using human breast adenocarcinoma cells SK-BR-3 demonstrated the feasibility of using azafluoranthenes as fluorescent probes.

Long-term outcome, with monitoring of platelet counts, in patients with chronic hepatitis C and liver cirrhosis after interferon therapy.

OBJECTIVE: Because the determination of the stage of fibrosis depends on rather subjective judgment, more objective parameters are needed. In this study, we followed the long-term outcome, with monitoring of platelet counts, in patients with chronic hepatitis C or liver cirrhosis (LC) who had undergone interferon (IFN) therapy. METHODS: 596 patients who were diagnosed at our institute from 1987 to 1998 with chronic hepatitis C and LC were treated with IFNs. A further 58 patients were not treated (NT). The annual rate of changes in platelet counts were calculated and compared for IFN-treated and NT patients. RESULTS: The relationship between the efficacy of IFN therapy and the incidence of hepatocellular carcinoma (HCC) showed that the patients who were virologic sustained responders (VSR) had a significantly lower incidence of HCC than the nonresponders (NR) and NT patients. The change in platelet counts was +4,350/microl/year in the VSR, +1,010/microl/year in the biochemical sustained responders (BSR), -4,540/microl/year in the NR and -6,180/microl/year in the NT patients, indicating a significant platelet increase in the VSR, a decrease of the same magnitude in the NR and NT patients, and no change in the BSR. The cumulative probability of developing HCC and liver failure was significantly higher in groups with decreased platelet counts than in groups with increased platelet counts among patients who had undergone IFN therapy. Multivariate analyses revealed that a decrease in platelet counts was the cardinal risk factor for development of HCC and liver failure in chronic hepatitis C or LC patients. CONCLUSION: Investigation of platelet counts was useful for determining the long-term outcome of patients who had undergone IFN therapy and for predicting the development of HCC.

Serum concentrations of human hepatocyte growth factor is a useful indicator for predicting the occurrence of hepatocellular carcinomas in C-viral chronic liver diseases.

BACKGROUND: Numerous reports have examined the relationship between hepatocyte growth factor (HGF) and either the facilitation or suppression of the occurrence of hepatocellular carcinoma (HCC). METHODS: In this study, we measured serum HGF concentrations of blood samples and conducted prospective studies to examine the long-term outcome of C-viral chronic hepatitis (CH) and cirrhosis in patients. The subjects examined in this study include 99 patients with C-viral CH, cirrhosis, and HCC. The serum HGF level was measured in blood samples within 48 hours of collection using enzyme-linked immunosorbent assay kits. RESULTS: The serum concentrations of HGF were significantly higher in patients with HCC than in patients with CH or cirrhosis. The detection rate of HGF and its mean serum level were significantly higher in patients with a low platelet count than in patients with a high platelet count. All of the patients with serum HGF concentrations of more than 0.6 ng/mL had HCC, irrespective of the levels of alpha-fetoprotein, vitamin K absence, or antagonist-II in the blood. Serum HGF concentrations increased concomitantly with increases in areas occupied by HCC. The cumulative incidence of occurrence of HCC was significantly higher in patients with high HGF concentrations than in patients with low HGF concentrations. Multivariate analysis revealed that the elevation in serum HGF level is the most important risk factor for the occurrence of HCC. CONCLUSIONS: The serum level of HGF represents the degree of the carcinogenic state in the liver of patients with C-viral CH and cirrhosis. Therefore, the determination of serum HGF concentrations may be useful as a third tumor marker of HCC in detection as well as follow-up therapy.