After the recent publication in the Journal of Biophysical Chemistry entitled “Retracted HIV Study Provides New Information about the Status of the in Vitro Inhibition of DNA Replication by Back-bone Methylation”, i...After the recent publication in the Journal of Biophysical Chemistry entitled “Retracted HIV Study Provides New Information about the Status of the in Vitro Inhibition of DNA Replication by Back-bone Methylation”, it is of importance to review the results of Buck’s group on the synthesis and conformation analyses of phosphate-methylated RNAs in order to afford information on the absence of a further investigation with regard to this de facto acceptable approach. In fact these compounds belong to the very first group of RNAs with a modified neutral backbone by phosphatemethylation. In contrast to the corresponding phosphate-methylated DNAs with a frozen B-conformation, the phosphate-methylated RNAs show an A-conformation. The latter is a prerequisite for duplex formation with (complementary) (natural) RNA. A number of experiments support this fundamental statement. After the HIV study was retracted, the overall results concerning the phosphate-methylated RNAs were published without mentioning Buck’s initial proof of concept and his contributions. Generally, the (modified) dimer RNAs and DNAs possess a number of specific biophysical properties. A novel explanation is given for conflicting structural determinations.展开更多
Benzo(a)pyrene metabolism in human placental microsomes fromsmokers was studied.Benzo(a)pyrene metabolites were separatedusing high pressure liquid chromatographic technique. Reactionof benzo(a)pyrene with microsomal ...Benzo(a)pyrene metabolism in human placental microsomes fromsmokers was studied.Benzo(a)pyrene metabolites were separatedusing high pressure liquid chromatographic technique. Reactionof benzo(a)pyrene with microsomal fraction of placenta fromindividuals who smoke cigarette during pregnency yields 7。展开更多
文摘After the recent publication in the Journal of Biophysical Chemistry entitled “Retracted HIV Study Provides New Information about the Status of the in Vitro Inhibition of DNA Replication by Back-bone Methylation”, it is of importance to review the results of Buck’s group on the synthesis and conformation analyses of phosphate-methylated RNAs in order to afford information on the absence of a further investigation with regard to this de facto acceptable approach. In fact these compounds belong to the very first group of RNAs with a modified neutral backbone by phosphatemethylation. In contrast to the corresponding phosphate-methylated DNAs with a frozen B-conformation, the phosphate-methylated RNAs show an A-conformation. The latter is a prerequisite for duplex formation with (complementary) (natural) RNA. A number of experiments support this fundamental statement. After the HIV study was retracted, the overall results concerning the phosphate-methylated RNAs were published without mentioning Buck’s initial proof of concept and his contributions. Generally, the (modified) dimer RNAs and DNAs possess a number of specific biophysical properties. A novel explanation is given for conflicting structural determinations.
文摘Benzo(a)pyrene metabolism in human placental microsomes fromsmokers was studied.Benzo(a)pyrene metabolites were separatedusing high pressure liquid chromatographic technique. Reactionof benzo(a)pyrene with microsomal fraction of placenta fromindividuals who smoke cigarette during pregnency yields 7。
文摘目的探讨RUNX3、P16和DAPK基因启动子DNA甲基化与非小细胞肺癌(non-small cell lung cancer,NSCLC)化疗敏感性的关系。方法选取2023年2月至2025年2月于株洲市中心医院接受铂类化疗的初治晚期NSCLC患者116例为研究对象,根据化疗疗效将其分为敏感组(n=81)和耐受组(n=35)。比较两组患者的病灶组织标本RUNX3、P16、DAPK基因启动子DNA甲基化情况、基因转录水平绝对定量,采用受试者操作特征曲线(receiver operating characteristic curve,ROC曲线)评估RUNX3、P16、DAPK基因表达水平对铂类化疗耐药的预测价值。结果耐受组患者肺癌组织的RUNX3、P16和DAPK基因启动子DNA甲基化比例均显著高于敏感组(P<0.05)。耐受组患者肺癌组织的RUNX3、P16和DAPK基因转录水平均显著低于敏感组(P<0.05)。ROC曲线显示,肺癌组织RUNX3、P16、DAPK基因转录水平预测NSCLC患者化疗敏感的最佳截断值分别为2.93×10^(6)、5.22×10^(4)、6.420×10^(5),曲线下面积(area under the curve,AUC)分别为0.726、0.748、0.763。三者联合预测NSCLC患者化疗敏感的AUC为0.883,敏感度为81.82%、特异性为78.05%。结论RUNX3、P16、DAPK基因甲基化可能是晚期NSCLC患者铂类化疗耐药的原因之一,早期测定此类基因转录水平对预估化疗耐药、制定个体化治疗方案具有积极作用。
