In this study,we showed that BiO Br nanoplates prepared at different pH values have substratedependent photocatalytic activities under visible-light irradiation. The BiO Br nanoplates synthesized at pH 1(BOB-1) degr...In this study,we showed that BiO Br nanoplates prepared at different pH values have substratedependent photocatalytic activities under visible-light irradiation. The BiO Br nanoplates synthesized at pH 1(BOB-1) degraded salicylic acid more effectively than did those obtained at pH 3(BOB-3),but the order of their photocatalytic activities in rhodamine B(RhB) degradation were reversed. Electrochemical Mott–Schottky and zeta-potential measurements showed that BOB-1 had a more positive valence band and lower surface charge,leading to superior photocatalytic activity in salicylic acid degradation under visible light. However,BOB-3 was more powerful in RhB degradation because larger numbers of superoxide radicals were generated via electron injection from the excited RhB to its more negative conduction band under visible-light irradiation; this was confirmed using active oxygen species measurements and electron spin resonance analysis. This study deepens our understanding of the origins of organic-pollutant-dependent photoreactivities of semiconductors,and will help in designing highly active photocatalysts for environmental remediation.展开更多
AIM: To assess if a specific cytotoxic T cell response can be induced in patients with malignant liver tumors treated with radio-frequency ablation (RFA). METHODS: Six Patients with liver metastases of colorectal ...AIM: To assess if a specific cytotoxic T cell response can be induced in patients with malignant liver tumors treated with radio-frequency ablation (RFA). METHODS: Six Patients with liver metastases of colorectal cancer and 6 with hepatocellular carcinoma (HCC) underwent RFA. Blood was sampled before, 4 and 8 wk after RFA. Test antigens were autologous liver and tumor lysate obtained from each patient by biopsy. Peripheral T cell activation was assessed by an interferon gamma (IFNγ) secretion assay and flow cytometry. T cells were double-stained for CD4/CD8 and IFNγ to detect cytotoxic T cells. The ratio of IFNγ positive and IFNγ negative T cells was determined as the stimulation index (SI). To assess cytolytic activity, T cells were co-incubated with human CaCo colorectal cancer and HepG2 HCC cells and release of cytosolic adenylate kinase was measured by a luciferase assay. RESULTS: Before RFA SI was 0.021 (±0.006) for CD4^+ and 0.022 (± 0.004) for CD8^+T cells against nonmalignant liver tissue and 0.018 (± 0.005) for CD4^+ and 0.021 (± 0.004) for CD8^+ cells against autologous tumor tissue. Four weeks after RFA SI against tumor tissue increased to 0.109 (± 0.005) for CD4+ and 0.11 (± 0.012) for CD8+ T cells against HCC, and to 0.115 (± 0.031) for CD4^+ and 0.15 (± 0.02) for CD8^+ cells for colorectal metastases (P 〈 0.0001). No increased SI was observed with nonmalignant tumor tissue at all time points. Before RFA cytolytic activity against the respect(ve cancer cells was low with 2.62 (± 0.37) relative luminescence units (RLU), but rose more than 100 fold 4 and 8 wk after RFA. Spontaneous release was 〈 2% of maximum release in all experiments. CONCLUSION: Patients with primary and secondary tumors of the liver show a significant tumor-specific cytotoxic T-cell stimulation with a dramatically increased tumor specific cytolytic activity of CD8^+ T cells after RFA.展开更多
基金supported by the National Natural Science Funds for Distinguished Young Scholars(21425728)the National Natural Science Foundation of China(21173093+4 种基金211770482127308821477044)the Key Project of Natural Science Foundation of Hubei Province(2013CFA114)the the Fundamental Research Funds for the Central Universities(CCNU14Z01001 CCNU14KFY002)~~
文摘In this study,we showed that BiO Br nanoplates prepared at different pH values have substratedependent photocatalytic activities under visible-light irradiation. The BiO Br nanoplates synthesized at pH 1(BOB-1) degraded salicylic acid more effectively than did those obtained at pH 3(BOB-3),but the order of their photocatalytic activities in rhodamine B(RhB) degradation were reversed. Electrochemical Mott–Schottky and zeta-potential measurements showed that BOB-1 had a more positive valence band and lower surface charge,leading to superior photocatalytic activity in salicylic acid degradation under visible light. However,BOB-3 was more powerful in RhB degradation because larger numbers of superoxide radicals were generated via electron injection from the excited RhB to its more negative conduction band under visible-light irradiation; this was confirmed using active oxygen species measurements and electron spin resonance analysis. This study deepens our understanding of the origins of organic-pollutant-dependent photoreactivities of semiconductors,and will help in designing highly active photocatalysts for environmental remediation.
基金Supported by the Bavarian Ministry of Economy (Leitprojekt Medizintechnik) and the Hans L(o|¨)wel Foundation, Bamberg,Germany
文摘AIM: To assess if a specific cytotoxic T cell response can be induced in patients with malignant liver tumors treated with radio-frequency ablation (RFA). METHODS: Six Patients with liver metastases of colorectal cancer and 6 with hepatocellular carcinoma (HCC) underwent RFA. Blood was sampled before, 4 and 8 wk after RFA. Test antigens were autologous liver and tumor lysate obtained from each patient by biopsy. Peripheral T cell activation was assessed by an interferon gamma (IFNγ) secretion assay and flow cytometry. T cells were double-stained for CD4/CD8 and IFNγ to detect cytotoxic T cells. The ratio of IFNγ positive and IFNγ negative T cells was determined as the stimulation index (SI). To assess cytolytic activity, T cells were co-incubated with human CaCo colorectal cancer and HepG2 HCC cells and release of cytosolic adenylate kinase was measured by a luciferase assay. RESULTS: Before RFA SI was 0.021 (±0.006) for CD4^+ and 0.022 (± 0.004) for CD8^+T cells against nonmalignant liver tissue and 0.018 (± 0.005) for CD4^+ and 0.021 (± 0.004) for CD8^+ cells against autologous tumor tissue. Four weeks after RFA SI against tumor tissue increased to 0.109 (± 0.005) for CD4+ and 0.11 (± 0.012) for CD8+ T cells against HCC, and to 0.115 (± 0.031) for CD4^+ and 0.15 (± 0.02) for CD8^+ cells for colorectal metastases (P 〈 0.0001). No increased SI was observed with nonmalignant tumor tissue at all time points. Before RFA cytolytic activity against the respect(ve cancer cells was low with 2.62 (± 0.37) relative luminescence units (RLU), but rose more than 100 fold 4 and 8 wk after RFA. Spontaneous release was 〈 2% of maximum release in all experiments. CONCLUSION: Patients with primary and secondary tumors of the liver show a significant tumor-specific cytotoxic T-cell stimulation with a dramatically increased tumor specific cytolytic activity of CD8^+ T cells after RFA.