为了鉴定异性双胎牛性器官发育紊乱疾病——牛自由马丁(freemartinism)综合征,试验选择7头中国荷斯坦异性孪生双胎的母牛进行微滴数字PCR(droplet digital PCR,ddPCR)检测,并根据异性孪生母犊不孕的个体染色体为XX/XY嵌合、正常母牛染...为了鉴定异性双胎牛性器官发育紊乱疾病——牛自由马丁(freemartinism)综合征,试验选择7头中国荷斯坦异性孪生双胎的母牛进行微滴数字PCR(droplet digital PCR,ddPCR)检测,并根据异性孪生母犊不孕的个体染色体为XX/XY嵌合、正常母牛染色体为XX来判定是否为嵌合体。结果表明:此7个样本均存在XX/XY染色体嵌合,均为异性孪生不孕母犊。说明ddPCR方法用于鉴定牛自由马丁现象是有效的。展开更多
Carassius auratus herpesvirus(CaHV)is a pathogen isolated from crucian carp(Carassius auratus)associated with high mortality.A diagnosis method that can detect the virus at an early stage,specifically and accurately,i...Carassius auratus herpesvirus(CaHV)is a pathogen isolated from crucian carp(Carassius auratus)associated with high mortality.A diagnosis method that can detect the virus at an early stage,specifically and accurately,is an urgent requirement for the prevention of CaHV transmission.In the present study,a droplet digital PCR(ddPCR)method based on the tumor necrosis factor receptor(TNFR)gene was established to detect and quantify CaHV DNA with high specificity and no cross-reactions with other aquatic viruses.Skin mucus samples were collected from infected crucian carp from Day 1–8 after infection,and positive amplification was detected on the first day by ddPCR(0.54 copies/μL),whereas the presence of CaHV was not detected by routine PCR until Day 6.Tissue DNA was then collected from the head kidney of 20 fishes which were injected with CaHV and died during the experiment.The five negative samples checked by routine PCR were detected by ddPCR and real-time PCR(qPCR),respectively.The results showed that the positive detection rate of ddPCR(100%)was higher than that of qPCR(40%).The detection limit of the ddPCR was found to be 0.52 copies/μL,which was much lower than the 50.12 copies/μL determined by qPCR.Overall,ddPCR offers a highly promising diagnosis method for the absolute quantification of CaHV in carrier fish and samples from the skin mucus and head kidney with low viral concentrations.展开更多
建立一种微滴式数字聚合酶链式反应(Droplet digital polymerase chain reaction,ddPCR)定量检测包装饮用水中铜绿假单胞菌的技术。根据铜绿假单胞菌外毒素A(ETA)基因序列合成特异性引物和探针,通过多种菌株扩增验证方法特异性,通过人...建立一种微滴式数字聚合酶链式反应(Droplet digital polymerase chain reaction,ddPCR)定量检测包装饮用水中铜绿假单胞菌的技术。根据铜绿假单胞菌外毒素A(ETA)基因序列合成特异性引物和探针,通过多种菌株扩增验证方法特异性,通过人工添加铜绿假单胞菌验证方法检出限。结果表明,建立的包装饮用水中铜绿假单胞菌ddPCR定量检测方法特异性强,检出限为10 CFU/mL,灵敏度高,适用性好。该方法可以满足包装饮用水中铜绿假单胞菌定量检测需求。展开更多
文摘为了鉴定异性双胎牛性器官发育紊乱疾病——牛自由马丁(freemartinism)综合征,试验选择7头中国荷斯坦异性孪生双胎的母牛进行微滴数字PCR(droplet digital PCR,ddPCR)检测,并根据异性孪生母犊不孕的个体染色体为XX/XY嵌合、正常母牛染色体为XX来判定是否为嵌合体。结果表明:此7个样本均存在XX/XY染色体嵌合,均为异性孪生不孕母犊。说明ddPCR方法用于鉴定牛自由马丁现象是有效的。
基金financially supported by the Science and Technology Commission of Shanghai Municipality(21ZR1427200).
文摘Carassius auratus herpesvirus(CaHV)is a pathogen isolated from crucian carp(Carassius auratus)associated with high mortality.A diagnosis method that can detect the virus at an early stage,specifically and accurately,is an urgent requirement for the prevention of CaHV transmission.In the present study,a droplet digital PCR(ddPCR)method based on the tumor necrosis factor receptor(TNFR)gene was established to detect and quantify CaHV DNA with high specificity and no cross-reactions with other aquatic viruses.Skin mucus samples were collected from infected crucian carp from Day 1–8 after infection,and positive amplification was detected on the first day by ddPCR(0.54 copies/μL),whereas the presence of CaHV was not detected by routine PCR until Day 6.Tissue DNA was then collected from the head kidney of 20 fishes which were injected with CaHV and died during the experiment.The five negative samples checked by routine PCR were detected by ddPCR and real-time PCR(qPCR),respectively.The results showed that the positive detection rate of ddPCR(100%)was higher than that of qPCR(40%).The detection limit of the ddPCR was found to be 0.52 copies/μL,which was much lower than the 50.12 copies/μL determined by qPCR.Overall,ddPCR offers a highly promising diagnosis method for the absolute quantification of CaHV in carrier fish and samples from the skin mucus and head kidney with low viral concentrations.