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
Background: The Air Force Health Study collected reproductive outcomes for live-born children of male Air Force veterans of the Vietnam War. Methods: Dioxin values for participants were obtained from blood samples. An...Background: The Air Force Health Study collected reproductive outcomes for live-born children of male Air Force veterans of the Vietnam War. Methods: Dioxin values for participants were obtained from blood samples. Analyses were conducted of occurrence of 16 specific categories of birth defects and developmental disabilities. Children were categorized as conceived before and after the start of participants’ Vietnam War service. Children conceived before the start of Vietnam War service were treated as being conceived when their fathers had unquantifiable dioxin values. Children conceived after the start of Vietnam War service for participants with missing dioxin values were excluded from primary analyses, but were used to assess the impact of their exclusion on conclusions. Correlation between values for specific categories for multiple children fathered by the same participant was accounted for. The dose-response relationship was treated as a step function increasing for dioxin values larger than adaptively identified individual thresholds changing with the specific category. Results: For 15 of 16 specific categories, the probability of occurrence increased substantially for a sufficiently high dioxin level above identified thresholds. Exclusion of children due to missing dioxin likely did not affect these results. Conclusions: Results supported the conclusion of substantial adverse effects on a wide variety of specific categories of birth defects and developmental disabilities due to sufficiently high exposures to dioxin, a toxic contaminant of Agent Orange used for herbicide spraying in the Vietnam War. Results may hold more generally, but might also have been affected by a variety of limitations.展开更多
Particular non-monotonic dose-response curves of many endocrine disrupting chemicals (EDCs) suggest the existence of diverse toxicity mechanisms at different dose levels. As a result, the biological activities of EDCs...Particular non-monotonic dose-response curves of many endocrine disrupting chemicals (EDCs) suggest the existence of diverse toxicity mechanisms at different dose levels. As a result, the biological activities of EDCs cannot be simply exhibited by unique EC50/LD50 values, and the quantitative structure-activity relationship (QSAR) analysis for non-monotonic dose-response relationship becomes an unknown field in the environmental science. In this paper, nine phenols with inverted U-shaped dose-response curves in lymphocyte proliferation test of Carassius auratus were selected. The binding interactions between the phenols and several typical EDCs-related receptors were then explored in a molecular simulation study. The estrogen receptor (ER), androgen receptor (AR), thyroid hormone receptor (TR), bacterial O2 sensing FixL protein (FixL), aryl hydrocarbon receptor (AhR), and the peroxisome proliferator-activated receptor (PPAR) were the target receptors in the study. Linear regression QSAR models for the low and high exposure levels of the compounds were developed separately. The results indicated that the lymphocyte proliferation in the low-dose range might involve ER–mediated process, while the proliferation inhibition in the high dose range was dominated by the acute toxicity of phenols due to receptor occupancy and cell damage.展开更多
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。
文摘Background: The Air Force Health Study collected reproductive outcomes for live-born children of male Air Force veterans of the Vietnam War. Methods: Dioxin values for participants were obtained from blood samples. Analyses were conducted of occurrence of 16 specific categories of birth defects and developmental disabilities. Children were categorized as conceived before and after the start of participants’ Vietnam War service. Children conceived before the start of Vietnam War service were treated as being conceived when their fathers had unquantifiable dioxin values. Children conceived after the start of Vietnam War service for participants with missing dioxin values were excluded from primary analyses, but were used to assess the impact of their exclusion on conclusions. Correlation between values for specific categories for multiple children fathered by the same participant was accounted for. The dose-response relationship was treated as a step function increasing for dioxin values larger than adaptively identified individual thresholds changing with the specific category. Results: For 15 of 16 specific categories, the probability of occurrence increased substantially for a sufficiently high dioxin level above identified thresholds. Exclusion of children due to missing dioxin likely did not affect these results. Conclusions: Results supported the conclusion of substantial adverse effects on a wide variety of specific categories of birth defects and developmental disabilities due to sufficiently high exposures to dioxin, a toxic contaminant of Agent Orange used for herbicide spraying in the Vietnam War. Results may hold more generally, but might also have been affected by a variety of limitations.
基金Supported by the National Natural Science Foundation of China (Grant Nos. 20777035 and 20377022) National High Technology Research and Development Program of China (Grant Nos. 2007AA06Z416 and 2006AA06Z424)
文摘Particular non-monotonic dose-response curves of many endocrine disrupting chemicals (EDCs) suggest the existence of diverse toxicity mechanisms at different dose levels. As a result, the biological activities of EDCs cannot be simply exhibited by unique EC50/LD50 values, and the quantitative structure-activity relationship (QSAR) analysis for non-monotonic dose-response relationship becomes an unknown field in the environmental science. In this paper, nine phenols with inverted U-shaped dose-response curves in lymphocyte proliferation test of Carassius auratus were selected. The binding interactions between the phenols and several typical EDCs-related receptors were then explored in a molecular simulation study. The estrogen receptor (ER), androgen receptor (AR), thyroid hormone receptor (TR), bacterial O2 sensing FixL protein (FixL), aryl hydrocarbon receptor (AhR), and the peroxisome proliferator-activated receptor (PPAR) were the target receptors in the study. Linear regression QSAR models for the low and high exposure levels of the compounds were developed separately. The results indicated that the lymphocyte proliferation in the low-dose range might involve ER–mediated process, while the proliferation inhibition in the high dose range was dominated by the acute toxicity of phenols due to receptor occupancy and cell damage.
