Objective This paper is to explore the DNA repair mechanism of immune adaptive response （AR） induced by low dose radiation （LDR）, the changes of mRNA levels and protein expressions of p53, ATM, DNA-PK catalytic su...Objective This paper is to explore the DNA repair mechanism of immune adaptive response （AR） induced by low dose radiation （LDR）, the changes of mRNA levels and protein expressions of p53, ATM, DNA-PK catalytic subunit （DNA-PKcs） and PARP-1 genes in the LDR-induced AR in EL-4 cells. Methods The apoptosis and cell cycle progression of EL-4 cells were detected by flow cytometry in 12 h after the cells received the pre-exposure of 0.075 Gy X-rays （inductive dose, D 1） and the succeeding high dose irradiation （challenge dose, D2; 1.0, 1.5, and 2.0 Gy X-rays, respectively） with or without wortmannin （inhibitor of ATM and DNA-PK） and 3-aminobenzamid （inhibitor of PARP-1）. And the protein expressions and mRNA levels related to these genes were detected with flow cytometry and reverse transcription-polymerase chain reaction in 12 h after irradiation with D2. Results The mRNA and protein expressions of p53 and PARP-1 in EL-4 cells in the D1 ＋ D2 groups were much lower than those in the D2 groups, and those of PARP-1 in the 3-AB ＋ D2 and the 3-AB ＋ D1 ＋ D2 groups were much lower than those in the D2 and the D1 ＋ D2 groups. The percentage of apoptotic EL-4 cells in the 3-AB ＋ D1 ＋ D2 groups was much higher than that in the D1 ＋ D2 groups, that in the G0/G1 and the G2 ＋ M phases was much higher, and that in the S phase were much lower. Although the ATM and DNA-PKcs mRNA and protein expressions in wortmannin ＋ D1 ＋ D2 groups were much lower than those in the D1 ＋ D2 groups, there were no significant changes in the apoptosis and cell cycle progression between the wortmannin ＋ D1 ＋ D2 and the D1 ＋ D2 groups. Conclusion PARP-1 and p53 might play important roles in AR induced by LDR.展开更多
Human lymphocytes pre-exposed to 10 mGy or 50 mGy of X-rays become less sensitive to subsequent large dose irradiation, exhibited lower rate of chromosome aberration than expected. This adaptive response could be inhi...Human lymphocytes pre-exposed to 10 mGy or 50 mGy of X-rays become less sensitive to subsequent large dose irradiation, exhibited lower rate of chromosome aberration than expected. This adaptive response could be inhibited by cycloheximide, a protein synthesis inhibitor for successive 2 h period ranging from 0.5h before to 4h after the low dose exposure, indicating that the adaptive response was directly related with the protein synthesis.展开更多
In this paper, the effect of irradiation temperature on sol fraction-dose relationship of tluoropolymers was studied. It was found that the increasing of irradiation temperature can result in the decreasing of β valu...In this paper, the effect of irradiation temperature on sol fraction-dose relationship of tluoropolymers was studied. It was found that the increasing of irradiation temperature can result in the decreasing of β value of fluoropolymer, which increases the crosslinking probability of fluoropolymer. The relationship between crosslinking parameter β and irradiation temperature (T_i)of fluoropolymer is established as follows:β=2.2×10^(-3) T_g+4×10^(-4)(T_g-T_i)+0.206.values of some tluoropolymers calculated from the above expression are in agreement with the experimental values.展开更多
The dose-response curves obtained by premature condensed chromosome (PCC)and conventional cellular genetic methods can be represented by two linear equations. The ratiO of the slopes, Kpcc/KM,, is about 28. In compari...The dose-response curves obtained by premature condensed chromosome (PCC)and conventional cellular genetic methods can be represented by two linear equations. The ratiO of the slopes, Kpcc/KM,, is about 28. In comparison to the conventional method, the PCC method has many advantages; e,g. it is faster, simpler, more sensitive and accurate. Its significance in the study of radiation damage is also discussed.展开更多
目的调查武汉地区居民体质量指数(body mass index,BMI)连续变化情况,探讨BMI与血脂异常患病风险的剂量-反应关系,为该地区血脂异常防控提供科学依据。方法采用多阶段分层抽样法,于2022年抽取武汉市江岸区18岁及以上常住居民进行问卷调...目的调查武汉地区居民体质量指数(body mass index,BMI)连续变化情况,探讨BMI与血脂异常患病风险的剂量-反应关系,为该地区血脂异常防控提供科学依据。方法采用多阶段分层抽样法,于2022年抽取武汉市江岸区18岁及以上常住居民进行问卷调查、身体测量和实验室检测。应用非条件逐步Logistic回归和限制性立方样条模型分析BMI与血脂异常患病关联及剂量-反应关系。结果最终共纳入3173例样本,武汉市江岸区居民超重、肥胖的标化患病率分别为31.30%和8.95%。血脂异常、高总胆固醇(TC)、高甘油三酯(TG)血症、高低密度脂蛋白(LDL-C)血症和低高密度脂蛋白(HDL-C)血症的标化患病率分别为20.49%、2.60%、9.78%、3.17%和6.08%。超重(OR=1.118,95%CI:1.083~1.154)和肥胖(OR=1.181,95%CI:1.123~1.243)与血脂异常患病显著相关。男性(χ^(2)=6.67,P<0.05)、女性(χ^(2)=6.07,P<0.05)、18~<45岁(χ^(2)=13.40,P<0.05)和45~<65岁(χ^(2)=8.02,P<0.05)人群的BMI与血脂异常患病呈非线性剂量-反应关系,随BMI升高,血脂异常患病风险逐渐增加继而又趋于平缓。而65岁及以上(χ^(2)=0.18,P>0.05)人群的BMI与血脂异常患病呈线性剂量-反应关系。结论BMI的连续变化和血脂异常的患病风险呈正相关的剂量-反应关系。血脂异常的指标预警防控工作需关口前移,应注重中青年的血脂防控工作,并通过倡导减轻体质量、进行早期预防和控制等措施,降低血脂异常患病风险。展开更多
基金supported by the National Natural Science Foundation of China(30570546 and 30870747)the Natural Science Foundation of Jilin Province (20090458 and 201015183)+1 种基金the Young Teachers Innovative Foundation of Jilin University(421010043430)the Young Scholars Research Foundation Program of China-Japan Union Hospital(2009)
文摘Objective This paper is to explore the DNA repair mechanism of immune adaptive response （AR） induced by low dose radiation （LDR）, the changes of mRNA levels and protein expressions of p53, ATM, DNA-PK catalytic subunit （DNA-PKcs） and PARP-1 genes in the LDR-induced AR in EL-4 cells. Methods The apoptosis and cell cycle progression of EL-4 cells were detected by flow cytometry in 12 h after the cells received the pre-exposure of 0.075 Gy X-rays （inductive dose, D 1） and the succeeding high dose irradiation （challenge dose, D2; 1.0, 1.5, and 2.0 Gy X-rays, respectively） with or without wortmannin （inhibitor of ATM and DNA-PK） and 3-aminobenzamid （inhibitor of PARP-1）. And the protein expressions and mRNA levels related to these genes were detected with flow cytometry and reverse transcription-polymerase chain reaction in 12 h after irradiation with D2. Results The mRNA and protein expressions of p53 and PARP-1 in EL-4 cells in the D1 ＋ D2 groups were much lower than those in the D2 groups, and those of PARP-1 in the 3-AB ＋ D2 and the 3-AB ＋ D1 ＋ D2 groups were much lower than those in the D2 and the D1 ＋ D2 groups. The percentage of apoptotic EL-4 cells in the 3-AB ＋ D1 ＋ D2 groups was much higher than that in the D1 ＋ D2 groups, that in the G0/G1 and the G2 ＋ M phases was much higher, and that in the S phase were much lower. Although the ATM and DNA-PKcs mRNA and protein expressions in wortmannin ＋ D1 ＋ D2 groups were much lower than those in the D1 ＋ D2 groups, there were no significant changes in the apoptosis and cell cycle progression between the wortmannin ＋ D1 ＋ D2 and the D1 ＋ D2 groups. Conclusion PARP-1 and p53 might play important roles in AR induced by LDR.
文摘Human lymphocytes pre-exposed to 10 mGy or 50 mGy of X-rays become less sensitive to subsequent large dose irradiation, exhibited lower rate of chromosome aberration than expected. This adaptive response could be inhibited by cycloheximide, a protein synthesis inhibitor for successive 2 h period ranging from 0.5h before to 4h after the low dose exposure, indicating that the adaptive response was directly related with the protein synthesis.
文摘In this paper, the effect of irradiation temperature on sol fraction-dose relationship of tluoropolymers was studied. It was found that the increasing of irradiation temperature can result in the decreasing of β value of fluoropolymer, which increases the crosslinking probability of fluoropolymer. The relationship between crosslinking parameter β and irradiation temperature (T_i)of fluoropolymer is established as follows:β=2.2×10^(-3) T_g+4×10^(-4)(T_g-T_i)+0.206.values of some tluoropolymers calculated from the above expression are in agreement with the experimental values.
文摘The dose-response curves obtained by premature condensed chromosome (PCC)and conventional cellular genetic methods can be represented by two linear equations. The ratiO of the slopes, Kpcc/KM,, is about 28. In comparison to the conventional method, the PCC method has many advantages; e,g. it is faster, simpler, more sensitive and accurate. Its significance in the study of radiation damage is also discussed.
文摘目的调查武汉地区居民体质量指数(body mass index,BMI)连续变化情况,探讨BMI与血脂异常患病风险的剂量-反应关系,为该地区血脂异常防控提供科学依据。方法采用多阶段分层抽样法,于2022年抽取武汉市江岸区18岁及以上常住居民进行问卷调查、身体测量和实验室检测。应用非条件逐步Logistic回归和限制性立方样条模型分析BMI与血脂异常患病关联及剂量-反应关系。结果最终共纳入3173例样本,武汉市江岸区居民超重、肥胖的标化患病率分别为31.30%和8.95%。血脂异常、高总胆固醇(TC)、高甘油三酯(TG)血症、高低密度脂蛋白(LDL-C)血症和低高密度脂蛋白(HDL-C)血症的标化患病率分别为20.49%、2.60%、9.78%、3.17%和6.08%。超重(OR=1.118,95%CI:1.083~1.154)和肥胖(OR=1.181,95%CI:1.123~1.243)与血脂异常患病显著相关。男性(χ^(2)=6.67,P<0.05)、女性(χ^(2)=6.07,P<0.05)、18~<45岁(χ^(2)=13.40,P<0.05)和45~<65岁(χ^(2)=8.02,P<0.05)人群的BMI与血脂异常患病呈非线性剂量-反应关系,随BMI升高,血脂异常患病风险逐渐增加继而又趋于平缓。而65岁及以上(χ^(2)=0.18,P>0.05)人群的BMI与血脂异常患病呈线性剂量-反应关系。结论BMI的连续变化和血脂异常的患病风险呈正相关的剂量-反应关系。血脂异常的指标预警防控工作需关口前移,应注重中青年的血脂防控工作,并通过倡导减轻体质量、进行早期预防和控制等措施,降低血脂异常患病风险。
