Synthesis of two glycolipid antigens of the causative agent of Lyme disease

As a prelude to development of a human vaccine against Lyme disease, the first chemical synthesis of glycolipid antigens of Borrelia burkholderi is reported. First, cholesteryl β-d-galactopyranoside was synthesized and was converted to partially protected congeners having the HO-6 group of the galactose moiety unprotected. Treatment of these intermediates with palmitic and oleic acid, respectively, under dehydrative conditions followed by removal of the protecting groups afforded cholesteryl 6-O-palmitoyl/oleoyl-β-d-galactopyranosides that were identical to the glycolipids isolated from B. burkholderi.     

Transitions in a genotype selection model driven by coloured noises

This paper investigates a genotype selection model subjected to both a multiplicative coloured noise and an additive coloured noise with different correlation time τ1 and τ2 by means of the numerical technique. By directly simulating the Langevin Equation, the following results are obtained. （1） The multiplicative coloured noise dominates, however, the effect of the additive coloured noise is not neglected in the practical gene selection process. The selection rate μ decides that the selection is propitious to gene A haploid or gene B haploid. （2） The additive coloured noise intensity and the correlation time τ2 play opposite roles. It is noted that α and τ2 can not separate the single peak, while can make the peak disappear and ~-2 can make the peak be sharp. （3） The multiplicative coloured noise intensity D and the correlation time τ1 can induce phase transition, at the same time they play opposite roles and the reentrance phenomenon appears. In this case, it is easy to select one type haploid from the group with increasing D and decreasing τ1.     

Silica microbeads capture fetal nucleated red blood cells for noninvasive prenatal testing of fetal ABO genotype

ABO hemolytic disease of the newborn (ABO-HDN), which may cause neonatal jaundice and polycythemia, or even stillbirth or neonatal death, is widespread in China. Prenatal testing for the fetal ABO blood group can reduce unnecessary concerns or ensure prompt treatment. Herein, we presented a method to employ high-density silica microbeads (SiO₂ MBs) for capturing fetal nucleated red blood cells (fnRBCs) in maternal peripheral blood, and we detected the ABO genotype of the fetus using these captured cells. We evaluated 52 patients using the SiO₂ MBs. Among 26 pregnant women with type O blood, 8 (30.8%) of the fetuses had type A blood, 5 (19.2%) had type B blood, and 13 (50%) had type O blood. SRY genes were detected in all 27 male fetuses. This study represents a simple and effective method for noninvasive prenatal detection of the fetal ABO genotype. We believe that this method has great potential for noninvasive prenatal testing of the fetal Rh blood group and other fetal diseases as well.     

A Reaction-diffusion System of a Prey with Three Genotypes and a Predator

The global existence and the asymptotic behavior of solutions to a reaction-diffusion system of a prey with three genotypes and a predator are considered. We establish the evolvement of a pure strain. Here an assumption concerning the diffusion is needed.     

On the Blum-Hanson theorem for quantum quadratic processes

In this paper an analog of the Blum-Hanson theorem for quantum quadratic processes on the von Neumann algebra is proved, i.e., it is established that the following conditions are equivalent:

Differentiation of Borrelia burgdorferi sensu lato species by temperature gradient gel electrophoresis

Borrelia burgdorferi sensu lato is a multispecies complex of pathogenic spirochetes, causing Lyme borreliosis. Due to clinical, epidemiological, and taxonomical implications, there is a need for identification of isolated Borrelia strains. In the present study, we have optimized TGGE for B. burgdorferi sensu lato species differentiation and the results were compared with two reference methods, namely PFGE and restriction of 5S-23S intergenic space region PCR product. A differentiation of B. garinii, B. afzelii, and B. burgdorferi senso stricto species with TGGE was possible and intraspecies variation was detected. Results compared between TGGE, PFGE, and restriction of 5S-23S intergenic space region PCR product showed no difference in specificity of species identification.     

随机基因选择模型中的延迟效应

研究了噪声驱动的基因选择模型中的延迟效应. 据小延迟方法和随机等价法则得到相应的延迟Fokker-Planck方程, 给出稳态概率分布函数的近似表达式. 分析了在噪声驱动下, 延迟时间对系统稳态性质的影响. 结果表明: 延迟时间可以诱导系统从单稳态向双稳态转化, 发生相变; 在基因选择过程中, 延迟时间有利于从基因群体中选择出某一单倍体基因. 数值模拟结果与理论预测基本符合.     

遗传群体的代数系统

根据生物遗传的内在规律,在多基因座配子中构造了一类运算,阐明了生物遗传具有交换的R-代数的数学结构,从而使遗传问题可用代数方法解决.文中利用这种代数所得到的因子频率定理,具有比Hardy-Weinberg平衡定律更为广泛的意义.同时,作为这种代数应用的例子,讨论了在连锁条件下群体基因型频率的计算问题,得到了一系列有意义的结果.     

基因互作形式的判定法则

如何根据子代的表型判断基因互作的形式以及确定亲代的基因型,是遗传学上重要的也是困难的问题.给出了解决上述问题的代数方法.在应用上,比以往任何方法更为广泛和方便.     

Noise in Genotype Selection Model

We study the steady state properties ofa genotype selection model in presence of correlated Gaussian whitenoise. The effect of the noise on the genotype selection model is discussed. It is found that correlated noise can breakthe balance of gene selection and induce the phase transition which can makes us select one type gene haploid from agene group.