亲和层析技术在生物科学中的应用及发展

近几十年来,亲和层析技术发展十分迅速,广泛应用于生物分子(如结合蛋白、酶、抑制剂、抗原、抗体、激素、激素受体、糖蛋白、核酸及多糖类等)及组织(如细胞、细胞器、病毒等)的分离和纯化,是蛋白质组学研究中重要的技术之一.介绍了亲和层析的基本类型及配体合成的研究进展,概述了亲和层析技术在蛋白质组学以及在其他方面的应用和发展动态.     

A More Realistic Approach to Pest-Management Problem

The paper deals with integrated pest management (IPM) of a single density-dependent pest affecting a single crop. The model is basically a prey–predator model, predator being the natural enemy of the pest. In addition, it also contains the growth equation of the affected crop. This dynamic model is subjected to biological control in the form of release of additional predators and chemical control in the form of spraying of pesticides. To consider the natural side effect of pesticide on fish living in the soil water, the model is further improved to accommodate the growth equation of the fishes in the soil water. The paper considers the optimal analysis of the model under two control parameters, one is the spraying of pesticide and other one is the release of predators; such optimal analysis under multi-control parameters is completely new of its kind. The paper was presented by S. Bhattacharyya in the conference “Joint AMS-India Mathematics Meeting,” 17–20 December 2003, India.     

Age-structured homogeneous epidemic systems with application to the MSEIR epidemic model

In this paper, we develop a new approach to deal with asymptotic behavior of the age-structured homogeneous epidemic systems and discuss its application to the MSEIR epidemic model. For the homogeneous system, there is no attracting nontrivial equilibrium, instead we have to examine existence and stability of persistent solutions. Assuming that the host population dynamics can be described by the stable population model, we rewrite the basic system into the system of ratio age distribution, which is the age profile divided by the stable age profile. If the host population has the stable age profile, the ratio age distribution system is reduced to the normalized system. Then we prove the stability principle that the local stability or instability of steady states of the normalized system implies that of the corresponding persistent solutions of the original homogeneous system. In the latter half of this paper, we prove the threshold and stability results for the normalized system of the age-structured MSEIR epidemic model.      

一类扩散循环系统正解的存在性与稳定性

利用上下解方法及全藕合线性互惠系统的最大值原理,研究了一类非线性椭圆系统,给出了其正解存在的充分必要条件,同时也得到了其正解局部稳定的某些结果．     

Testing a Partial Ordering of Population Means with Application to Inference about Growth Habits of Cowpea Genotypes

Using general results available in the literature, we derive the likelihood ratio test for a particular partial ordering of means that naturally arises in a biological context. We then show that the conceptual and computational complexity of the derivation can be substantially reduced by equivalently deriving the test using the intersection-union principle for decomposing a complex null hypothesis into elemental forms. A Monte Carlo algorithm for obtaining the p-value of the test is proposed. The test procedure is illustrated with a data set of the competitive ability of several cowpea genotypes, where previous experiments have indicated the proposed partial order of the means. A simulation study is used to examine the power of the test.     

A Novel Atlas-Based Strategy for Understanding Cardiac Dysfunction in Patients with Congenital Heart Disease

Tetralogy of Fallot (TOF) is the most common form of cyanotic congenital heart disease. Infants diagnosed with TOF require surgical interventions to survive into adulthood. However, as a result of postoperative structural malformations and long-term ventricular remodeling, further interventions are often required later in life. To help identify those at risk of disease progression, serial cardiac magnetic resonance (CMR) imaging is used to monitor these patients. However, most of the detailed information on cardiac shape and biomechanics contained in these large four-dimensional (4D) data sets goes unused in clinical practice for lack of efficient and comprehensive quantitative analysis tools. While current global metrics of cardiac size and function, such as indexed ventricular mass and volumes, can identify patients at risk of further complications, they are not adequate to explain the underlying mechanisms causing the postoperative malfunctions, and help cardiologists plan optimal personalized treatments. We are proposing a novel approach that uses 4D ventricular shape models derived from CMR imaging exams to generate statistical atlases of ventricular shape and finite-element models of ventricular biomechanics to identify specific features of cardiac shape and biomechanical properties that explain variations in ventricular function. This study has the potential to discover novel biomarkers that precede adverse ventricular remodeling and dysfunction.     

整合代谢组学和生物信息学策略在解析中药系统复杂性中的应用

中药在化学组成方面的复杂性决定了其作用方式和作用过程的复杂性。传统研究方法缺乏系统性,使得一系列制约中药现代化发展的关键问题一直未能得到很好的解决,包括中药化学物质组表征、中药作用机制、中药方剂配伍规律以及中药毒性机制等中药系统复杂性问题。代谢组学作为一门全新的组学技术,秉承了从机体全局系统出发来考量机体内源性小分子物质与外源性干预物质（如药物）的相互作用的理念,与在中医药理论指导下的中药作用原理思路一致。近年来,人们尝试将整合代谢组学技术和生物信息学策略用于解开上述中药关键问题,并已取得了一定的成果。但其在理论挖掘、策略设计、方法开发和实践拓展诸多方面都有很多具体的工作需要进一步推进。对整合代谢组学和生物信息学策略在解析中药系统复杂性中的应用进行综述。     

Effect of conditioning contraction intensity on postactivation potentiation is muscle dependent

We aimed to examine whether the influence of conditioning contraction intensity on the extent of postactivation potentiation (PAP) is muscle dependent. Eleven healthy males performed both thumb adduction and plantar flexion as a conditioning contraction. The conditioning contraction intensities were set at 20%, 40%, 60%, 80%, or 100% of the maximal voluntary isometric contraction (MVC).Before and after the conditioning contraction, twitch torque was measured for the respective joint to calculate the extent of PAP. In plantar flexion, the extent of PAP became significantly larger as the conditioning contraction intensity increased up to 80% MVC (p < 0.05). In contrast, the extent of PAP in thumb adduction increased significantly only up to 60% MVC (p < 0.05), but not at higher intensities.These results indicate that the influence of the conditioning contraction intensity on the extent of PAP is muscle dependent. Our results suggest that a conditioning contraction with submaximal intensity can sufficiently evoke sizable PAP in the muscle where most of muscle fibers are recruited at submaximal intensities, thereby attenuating muscle fatigue induced by the conditioning contraction.     

树鼩乳汁的主要成分检测及其意义

目的：探讨树鼩乳汁的基本成份,并和其它乳制品成份进行了比较分析。方法选取10只分娩后（1-21）d期间的哺乳期母树鼩,用人工被动母乳喂养方法让仔树鼩自由吮吸母乳,立即采用无菌操作的方法用注射器直接采取仔树鼩胃内的乳汁,1次／2 d,连续3-5次,每只母树鼩采取18 mL乳汁,按照国家标准的方法进行成分检测。结果树鼩乳汁总固形物为43.63％、脂肪为26.01％、蛋白质为10.41％、乳糖为0.45％、灰分为0.99％。树鼩乳的总固形物、灰分、蛋白质、脂肪、乳糖含量分别为牛乳的3.36、1.24、2.74、6.67、0.09倍;树鼩乳的总固形物、灰分、蛋白质、脂肪、乳糖含量分别为婴幼儿配方乳的1.44、0.20、0.58、1.53、0.06倍;与牛乳及婴幼儿配方乳矿物质成分含量相比,树鼩乳的矿物质成分钙、磷、钾、钠、镁、铁、锌含量均大于牛乳,分别为1.83、2.73、1.25、1.93、1.28、1.48倍,而均小于婴幼儿配方乳,分别为0.66、0.85、0.34、0.26、0.85、0.24、0.49倍。结论树鼩乳的主要营养成分呈现高脂高蛋白低糖的类型,可为树鼩人工育幼和饲养工作提供依据。     

老年痴呆症中神经递质释放异常的机理

阿尔茨海默症(Alzheimer’s disease,AD)是以胞外淀粉样蛋白(amyloid-β,Aβ)沉积和胞内神经纤维缠结为病理特征的神经退行性疾病。AD典型症状的出现与中枢神经系统突触数量的减少密切相关,因此,明确AD早期突触数量还没有明显降低时突触功能失调的机制对AD的临床诊治具有十分重要的意义。寡聚Aβ、早老素功能缺失等因素造成的突触前神经递质释放异常很有可能是AD突触功能异常的上游机制。对AD中神经递质释放异常的现象和机制进行综述,并对这一领域存在的开放问题作一归纳。