Induction of manganese-superoxide dismutase by membrane-binding drugs in Escherichia coli

Treatment of exponentially growing cells of Escherichia coli with membrane-binding drugs such as chlorpromazine (CPZ) and procaine resulted in an induction of manganese-superoxide dismutase (Mn-SOD). A slight decrease was observed in the amount of Fe-SOD. The induction of Mn-SOD required de novo synthesis of this enzyme, since it was suppressed by rifampin. The treatment did not cause the induction of Mn-SOD when performed under anaerobic conditions. In E. coli cells with a sodA-lacZ operon fusion, CPZ and procaine induced beta-galactosidase in the presence of oxygen, whereas it was not expressed and was not induced by CPZ and procaine under anaerobic conditions. Although CPZ reduced the ability of cell suspensions to take up oxygen, it increased the cyanide-resistant fraction of the total respiration. Therefore, it appeared likely that the induction of the sodA gene was a response to an increase in superoxide radical production mediated by these membrane-binding drugs in E. coli cells, possibly by disruption of the electron transport systems in the cell membranes.

[Clinical study of subclinical hepatic cancer--analysis of 187 patients]

187 patients with subclinical hepatic cancer (SHC), collected by mass screening or follow-up of the hepatic diseases in our hospital from Dec. 1972 to Dec. 1984, are reported. The age ranged from 18 to 76 years with a median of 47. The sex ratio of male and female was 1.97:1. 143 (76.5%) patients had a positive pathology. The exploration rate was 60.4% and resection rate was 77.9%. Of them, there were 72 (81.8%) small liver cancers with lesions equal to or less than 5 cm in diameter. For patients with resection, the 1, 3 and 5 year survival rates were 77.3%, 39.3% and 34.6%, markedly higher than those treated by other means. B-ultrasonography gave a significantly higher positive rate (96.4%) in the localization of SHC, compared with nuclide imaging (17.6%). Basing on analysis of 187 patients with SHC, close follow-up of the subjects with low level persistent positive alpha-fetoprotein without active liver disease plays an important role in the early detection of SHC.

[Fine needle aspiration cytology in the diagnosis of primary liver cancer]

From Dec. 1979 to Dec. 1984, 171 patients suspicious of primary liver cancer (PLC) were examined by fine needle aspiration cytology (FNAC). In this series, 148 patients were finally diagnosed as PLC. By FNAC, 133 of 148 patients showed positive cytology and 4 suspiciously positive cytology. The overall diagnostic accuracy was 92.6% There was no false positive. Neither spreading or bleeding were observed. The results show that FNAC examination, being simple, rapid and safe, could serve as a reliable way of diagnosing the suspected PLC.