Prenatal detection of fetal hemoglobin E gene from maternal plasma

In order to provide a noninvasive prenatal diagnosis of the hemoglobin E (Hb E) related disorder, we have evaluated the possibility of identifying the fetal β^E-globin gene in maternal plasma. The analysis was performed during 8 to 18 weeks of gestation using DNA extracted from 200 µL of plasma from pregnant women whose husbands carried Hb E. The β^E-globin mutation in maternal plasma was detected by a nested PCR amplification followed by the Mnl I restriction analysis. The result was compared with that of routine analysis of the CVS specimens. Among the five pregnant women examined, the fetal β^E-globin gene was identified in maternal plasma in three of them and the result was completely concordant with the conventional CVS analysis. This simple noninvasive prenatal detection of the fetal β^E-globin gene should prove useful in a prevention and control program of Hb E/β-thalassemia in countries where the β^E-globin gene is prevalent. Copyright © 2003 John Wiley & Sons, Ltd.     

基于PHB碳源驱动的同时硝化/反硝化除磷过程

构建厌氧/限氧曝气的序批式生物系统(A/OLASBR),以碳源偏低模拟城市污水为对象,在连续(CA)和间歇曝气(IA)模式下,研究以PHB为碳源驱动的同时硝化/反硝化除磷(SNDPR)过程,并考察了PHB、氧化还原电位(ORP)和pH值的变化规律与SNDPR持续稳定性之间的关系.结果表明,在恒定气量为40 L·h-1的CA模式下TN和TP去除率分别为79.9%和92.8%;而IA模式下曝气百分数(AF)和曝气频率(fIA)值为0.5和24时,TN与TP去除率分别为87.9%和93.5%,PHB降解速率平稳,ORP均值均化程度最好,ORP和pH值的稳定性最强.因此,低AF和高fIA的IA模式可缓冲PHB降解速率,均衡硝化与反硝化除磷速率,有利于SNDPR过程的持续稳定,且ORP均值的均化程度与ORP和pH值的稳定性可控制SNDPR过程的持续稳定.     

Ultrasonographic method for detection of haemoglobin Bart's hydrops fetalis in the second trimester of pregnancy

In nine pregnant women at risk for fetal alpha-thalassaemia, the two affected fetuses were diagnosed by ultrasonography at 18–20 weeks' gestation. In countries with limited resources, ultrasonography provides a cost-effective method of prenatal screening for this condition.