ABSTRACT
Objective To compare the changes in nitric oxide (NO), total ability of anti-oxidize antioxidase, superoxide dismutase (SOD), glutathion peroxidase (GSH-PX), catalase (CAT) and maleic dialdehyde(MDA) in rats after single and accumulative 60Co γ-irradiation . Methods 48 rats were randomly divided into two groups of single and accumulative irradiation. Each group was irradiated by 60Co gamma-rays. The total irradiation doses were 0.4, 0.8, 1.6, 3.2 and 6.4 Gy, respectively in each group. The NO, total ability of anti-oxidize antioxidaze, SOD, GSH-PX, CAT and MDA in serum were measured at day 1 after last irradiation. Results Compared with the single irradiation group, the NO (52.6-117.9 μmol/ml), total ability of anti-oxidize antioxidaze (3.3-26.2 U/ml), the antioxidase activity of the SOD (26.3-167.5 U/ml), GSH-PX (740.8-2462.4 U/ml), CAT (3.3-29.4 U/ml) and the content of MDA(29.3-155.1 nmol/ml) of mt serum in accumulative irradiation group were increased after irradiation, which was related with the accumulative irradiation dose. For instance, total ability of anti-oxidize antioxidase (26.2 U/ml), antioxidase activity of the SOD (167.5 U/ml) and CAT (29.4 U/ml) in 0.4 Gy group of accumulative irradiation were significandy increased when compared with those of control group. However, the content of MDA in accumulative irradiation group was obviously higher than that in single radiation group when the irradiation doses delivered over 3.2 Gy, which might be correlated with higher antioxidase activity. Conclusions Low dose of accumulative gamma-rays irradiation can induce the stimulative effect of antioxidase activity. However, higher dose of accumulative gamma-rays irradiation can damage the activity of antioxidase.
ABSTRACT
Objective To study the bystander effects and associated mechanisms through irradiated conditioned medium(1CM). Methods Natural kilhr(NK) cells were obtained from peripheral blood samples. ICM irradiated with different doses of 60Coγ-rays was used for culturing K562 cell strain. The degree of injury of K562cells by activated NK cells was observed, as well as the apoptosis frequency of K562 cell was investigated. Results Severe injury was induced in K562 cells cultured in ICM than the control (sham-irradiated) as shown by increased sensitivity to NK cells (P < 0.05). The apoptosis frequency of K562 cell was increased significantly compared with the control cells (P < 0.05). Conclusions The bystander effect induced by irradiation is existent. ICM can trigger the bystander effect on K562 cell strains.
ABSTRACT
Objective To observe the effects of T-lymphocyte function subsets,IL-4 and IFN-γ cell factor in different dose and stage after irradiation.Methoda The C57BL/6j mice were divided into shammed irradiation group and model groups.The radiation hurt model was induced by 60Co gamma rays(0.7,1.4,2.8 and 5.6 Gy).The changes of T-lymphocyte subsets CD3,CD4,CD8,IL-4 and IFN-γ in spleen cells were analyzed by flow cytometry in acute injury stage and recovery stage after irradiation.Results The lymphocyte subsets CD3 +,CD4+ and CD8 + decreased after irradiation,which were related to the irradiation dose.At 1 day after irradiation,the decreasing level of IFN-γ was higher than that of IL-4.When irradiation dose was over 2.8 Gy,IL-4 / IFN-γ showed a markedly increased compared with control group.At 25 days after irradiation,CD3 +,CD4+,CD8 +,CD4 +/CD8 +,IL-4 and IFN-γ recovered obviously,but they did not recover to the normal level of shammed irradiation group.Conclusions The depression of mouse immune function induced by γ-irradiation might be caused by changes of CD3,CD4,CD8 and CD4/CD8 ratio,especially the imbalance of IL4 and IFN-γ.
ABSTRACT
On the basis of systematic analysis for the current status of scientific research project mid-term management, we described several disadventages in the meddle management and gave some sugges-tions which included thinking highly of the role of supporting institutions, promoting the service conscious-ness, improving the project management ability of the manager and exploring new management methods of scientific research. Following these suggestions it would be make the meddle management much better and improving the research qualities.