目的探讨NDRG4甲基化检测在结直肠癌诊断中的价值。方法从84例结直肠癌手术切除癌组织、癌旁组织及其术前粪便、尿、血中提取DNA,应用巢式甲基化特异性PCR(nested methylation specific PCR,nMSP)检测结直肠癌粪便、尿、血中NDRG4基因...目的探讨NDRG4甲基化检测在结直肠癌诊断中的价值。方法从84例结直肠癌手术切除癌组织、癌旁组织及其术前粪便、尿、血中提取DNA,应用巢式甲基化特异性PCR(nested methylation specific PCR,nMSP)检测结直肠癌粪便、尿、血中NDRG4基因甲基化水平。比较结直肠癌组织和粪便、尿、血中NDRG4甲基化检测在结直肠癌诊断中的敏感性和特异性。结果在84例结直肠癌中,癌组织NDRG4检出率为81.0%,癌旁组织检出率为8.3%,敏感性为81.0%,特异性为91.7%;结直肠癌中粪便NDRG4基因甲基化的敏感性和特异性在3个微量DNA中最高,尿次之。结论结直肠癌组织NDRG4基因甲基化异常发生率高;粪便和尿中NDRG4甲基化异常可作为结直肠癌早期诊断的肿瘤标志物。展开更多
目的:考察在不同温度下储存时间和反复冻融对粪便中人基因组DNA含量的影响。方法:1.将粪便样本在室温、4℃、-40℃和-70℃条件下分别放置不同时间和-40℃条件下保存并反复冻融后,使用QIAamp DNA Stool Mini Kit试剂盒提取得到粪便DNA,...目的:考察在不同温度下储存时间和反复冻融对粪便中人基因组DNA含量的影响。方法:1.将粪便样本在室温、4℃、-40℃和-70℃条件下分别放置不同时间和-40℃条件下保存并反复冻融后,使用QIAamp DNA Stool Mini Kit试剂盒提取得到粪便DNA,通过实时荧光定量PCR体系对人KRAS基因定量确定人基因组DNA含量,评价粪便样本不同冻存条件对其中人基因组DNA含量的影响。2.将粪便DNA样本在4℃和-40℃条件下分别放置不同时间和-40℃条件下保存并反复冻融后,评价粪便DNA样本不同冻存条件下对其中人基因组DNA含量的影响。结果:1).粪便样本常温放置2小时,其中人基因组DNA即发生明显降解(P<0.01),4℃可保存3天左右,-40℃可保存4周,-70℃可保存3个月以上,粪便反复冻融第3次,其中人基因组DNA降解具有统计学意义(P<0.05)。2).粪便DNA 4℃可保存3天,-40℃可保存4周,粪便DNA反复冻融第4次,其中人基因组DNA降解具有统计学意义(P<0.05)。结论:符合大肠癌早期无创分子诊断要求的粪便DNA贮存条件:粪便样本室温收集后尽快保存;短期可处理的粪便样本存放在4℃条件下(3天内);暂无法处理则存于-40℃(1个月内);粪便样本长期保存在-70℃条件下,可保存3个月。展开更多
目的观察改变细菌裂解温度对提取粪便细菌基因组DNA量和纯度的影响。方法收集10例肝硬化患者粪便,每例患者粪便等分成两份,再随机分成两组。采用QIAamp DNA Stool Mini Kit试剂盒(国际通用粪便细菌基因组DNA提取试剂盒)进行抽提,一组(A...目的观察改变细菌裂解温度对提取粪便细菌基因组DNA量和纯度的影响。方法收集10例肝硬化患者粪便,每例患者粪便等分成两份,再随机分成两组。采用QIAamp DNA Stool Mini Kit试剂盒(国际通用粪便细菌基因组DNA提取试剂盒)进行抽提,一组(A组)按照试剂盒说明书温度要求进行粪便细菌基因组DNA提取,一组(B组)对试剂盒细菌裂解温度改良后再进行提取。结果与按照试剂盒说明书温度进行提取组相比,改变细菌裂解温度后粪便基因组DNA提取量明显增高(P<0.05),而粪便基因组DNA提取纯度(OD260/280、OD260/230)无明显变化(P>0.05)。结论改变细菌裂解温度能明显提高粪便细菌基因组DNA提取量,而不改变粪便细菌基因组DNA的提取纯度。该方法可以解决因粪便采样量少导致粪便基因组DNA提取量不足的问题。展开更多
Multitarget stool DNA(mt-sDNA) testing was approved for average risk colorectal cancer(CRC) screening by the United States Food and Drug Administration and thereafter reimbursed for use by the Medicare program(2014).T...Multitarget stool DNA(mt-sDNA) testing was approved for average risk colorectal cancer(CRC) screening by the United States Food and Drug Administration and thereafter reimbursed for use by the Medicare program(2014).The United States Preventive Services Task Force(USPSTF) October 2015 draft recommendation for CRC screening included mt-s DNA as an "alternative" screening test that "may be useful in select clinical circumstances",despite its very high sensitivity for early stage CRC.The evidence supporting mt-s DNA for routine screening use is robust.The clinical efficacy of mt-s DNA as measured by sensitivity,specificity,life-years gained(LYG),and CRC deaths averted is similar to or exceeds that of the other more specifically recommended screening options included in the draft document,especially those requiring annual testing adherence.In a population with primarily irregular screening participation,tests with the highest point sensitivity and reasonable specificity are more likely to favorably impact CRC related morbidity and mortality than those depending on annual adherence.This paper reviews the evidence supporting mt-s DNA for routine screening and demonstrates,using USPSTF's modeling data,that mt-s DNA at three-year intervals provides significant clinical net benefits and fewer complications per LYG than annual fecal immunochemical testing,high sensitivity guaiac based fecal occult blood testing and 10-year colonoscopy screening.展开更多
文摘目的探讨NDRG4甲基化检测在结直肠癌诊断中的价值。方法从84例结直肠癌手术切除癌组织、癌旁组织及其术前粪便、尿、血中提取DNA,应用巢式甲基化特异性PCR(nested methylation specific PCR,nMSP)检测结直肠癌粪便、尿、血中NDRG4基因甲基化水平。比较结直肠癌组织和粪便、尿、血中NDRG4甲基化检测在结直肠癌诊断中的敏感性和特异性。结果在84例结直肠癌中,癌组织NDRG4检出率为81.0%,癌旁组织检出率为8.3%,敏感性为81.0%,特异性为91.7%;结直肠癌中粪便NDRG4基因甲基化的敏感性和特异性在3个微量DNA中最高,尿次之。结论结直肠癌组织NDRG4基因甲基化异常发生率高;粪便和尿中NDRG4甲基化异常可作为结直肠癌早期诊断的肿瘤标志物。
文摘目的:考察在不同温度下储存时间和反复冻融对粪便中人基因组DNA含量的影响。方法:1.将粪便样本在室温、4℃、-40℃和-70℃条件下分别放置不同时间和-40℃条件下保存并反复冻融后,使用QIAamp DNA Stool Mini Kit试剂盒提取得到粪便DNA,通过实时荧光定量PCR体系对人KRAS基因定量确定人基因组DNA含量,评价粪便样本不同冻存条件对其中人基因组DNA含量的影响。2.将粪便DNA样本在4℃和-40℃条件下分别放置不同时间和-40℃条件下保存并反复冻融后,评价粪便DNA样本不同冻存条件下对其中人基因组DNA含量的影响。结果:1).粪便样本常温放置2小时,其中人基因组DNA即发生明显降解(P<0.01),4℃可保存3天左右,-40℃可保存4周,-70℃可保存3个月以上,粪便反复冻融第3次,其中人基因组DNA降解具有统计学意义(P<0.05)。2).粪便DNA 4℃可保存3天,-40℃可保存4周,粪便DNA反复冻融第4次,其中人基因组DNA降解具有统计学意义(P<0.05)。结论:符合大肠癌早期无创分子诊断要求的粪便DNA贮存条件:粪便样本室温收集后尽快保存;短期可处理的粪便样本存放在4℃条件下(3天内);暂无法处理则存于-40℃(1个月内);粪便样本长期保存在-70℃条件下,可保存3个月。
文摘目的观察改变细菌裂解温度对提取粪便细菌基因组DNA量和纯度的影响。方法收集10例肝硬化患者粪便,每例患者粪便等分成两份,再随机分成两组。采用QIAamp DNA Stool Mini Kit试剂盒(国际通用粪便细菌基因组DNA提取试剂盒)进行抽提,一组(A组)按照试剂盒说明书温度要求进行粪便细菌基因组DNA提取,一组(B组)对试剂盒细菌裂解温度改良后再进行提取。结果与按照试剂盒说明书温度进行提取组相比,改变细菌裂解温度后粪便基因组DNA提取量明显增高(P<0.05),而粪便基因组DNA提取纯度(OD260/280、OD260/230)无明显变化(P>0.05)。结论改变细菌裂解温度能明显提高粪便细菌基因组DNA提取量,而不改变粪便细菌基因组DNA的提取纯度。该方法可以解决因粪便采样量少导致粪便基因组DNA提取量不足的问题。
文摘Multitarget stool DNA(mt-sDNA) testing was approved for average risk colorectal cancer(CRC) screening by the United States Food and Drug Administration and thereafter reimbursed for use by the Medicare program(2014).The United States Preventive Services Task Force(USPSTF) October 2015 draft recommendation for CRC screening included mt-s DNA as an "alternative" screening test that "may be useful in select clinical circumstances",despite its very high sensitivity for early stage CRC.The evidence supporting mt-s DNA for routine screening use is robust.The clinical efficacy of mt-s DNA as measured by sensitivity,specificity,life-years gained(LYG),and CRC deaths averted is similar to or exceeds that of the other more specifically recommended screening options included in the draft document,especially those requiring annual testing adherence.In a population with primarily irregular screening participation,tests with the highest point sensitivity and reasonable specificity are more likely to favorably impact CRC related morbidity and mortality than those depending on annual adherence.This paper reviews the evidence supporting mt-s DNA for routine screening and demonstrates,using USPSTF's modeling data,that mt-s DNA at three-year intervals provides significant clinical net benefits and fewer complications per LYG than annual fecal immunochemical testing,high sensitivity guaiac based fecal occult blood testing and 10-year colonoscopy screening.
