RESUMO
Objective To investigate the effects of signal transducer and activator of transcription 3 (STAT3) RNAi on the content of reactive oxygen species (ROS) and the DNA damage in glioma cells.Methods Glioma cells of the line U251 cells were cultured and transfected with STAT3 RNAi plasmid (pSilencer2.1-STAT3,STAT3 group) and pSilencer2.1-GFP (GFP control group) respectively.Part of the U251 cells were irradiated with γ-rays of 60Co as positive control group of smear phenomenon.The levels of ROS and malondialdehyde (MDA) in the cells were detected 24,48,and 72 h later by flow cytometry and fluorescence chamoluminescence analyzer,respectively.The DNA damage in the transfected U251 cells was examined by using single cell gel electrophoresis assay,and the cell cycle distribution was examined using FACS PI staining 12,24,and 36 h later.Results At 24 h after the transfection,the ROS level of the siSTAT3-transfected ceils was 8.91 times that of the control group (F = 89.296,P < 0.05),and returned to the normal level 48 h later.There were not significant differences in the MDA level of the cells 24,48,and 72 h later between the siSTAT3 group and siGFP group.Compared with the 8 Gy irradiation positive group with obvious smear phenomenon,smear phenomenon was shown in part of the ceils in the siSTAT3 group 6 h later,became less 12 h later,and disappeared completely 24 h later.Compared with the control group,lag of S stage rate was 17.22% and the lag of G2/M stage rate was 6.4% 12 h later in the siSTAT-transfected group,and the G0/G1 stage lag rate was 18.44% 24 h later,and the lag of S stage rate was 17.99% 36 h later.Conclusions Inhibition of STAT3 results in the change of oxidoreduction status in glioma cells,as well as damage and reparation of DNA.
RESUMO
After the medical handling of a patient exposed to extremely uneven total body irradiation from an 192ir source (the activity was 2.765 TBq) on January 5, 1996 in Jilin City in order to afford new experience and information for similar case in the future. The authors emphasize the early amputation as the key to success, the importance of rhG-CSF effect and the significance of rational nutrition for the support of the patient, who had total body irradiation, massive local radiation injury and extensive surgical intervention to sustain. The document describe the accident, early clinical manifestation and posterior clinical manifestations (peripheral blood changes and bone marrow examination), evolution of local radiation injury; the assay of myocardial and musculature enzymes; assay of hemopoietic activity in the patient's sera and the treatment
Assuntos
Liberação Nociva de Radioativos , Lesões por Radiação , Efeitos da Radiação , Aberrações Cromossômicas , China , Relação Dose-Resposta à Radiação , Transplante de Medula ÓsseaRESUMO
Fragments of ? and ? genes were cloned into expression plasmid pET-21b. Bacteria harbouring expression plasmid was induced with IPTG,and a band of expressed protein of 16 kD was found in PAGE. They expressed as soluble products. ? expression product reached about 5% of total bacterial protein,? expression product reached about 15% of total bacterial protein. The products were confirmed by Western-blotting.
