凤尾草提取物的抗肿瘤活性的研究

采用小鼠腋下接种肿瘤细胞法测定凤尾草提取物的抗肿瘤活性、胸腺指数和脾指数,并采用MTT法测定了凤尾草提取物对小鼠脾细胞的增殖活性。结果显示凤尾草提取物对移植性肿瘤(肉瘤S180和肝癌H22)具有显著的抑制作用,可提高胸腺指数和脾指数,对小鼠脾细胞的增殖具有促进作用,并有较好的剂量依赖关系,表明中药凤尾草有可能是通过增强机体的免疫能力来实现其抗肿瘤活性的。     

Global dynamics of a cell mediated immunity in viral infection models with distributed delays

In this paper, we investigate global dynamics for a system of delay differential equations which describes a virus-immune interaction in vivo. The model has two distributed time delays describing time needed for infection of cell and virus replication. Our model admits three possible equilibria, an uninfected equilibrium and infected equilibrium with or without immune response depending on the basic reproduction number for viral infection R₀ and for CTL response R₁ such that R₁<R₀. It is shown that there always exists one equilibrium which is globally asymptotically stable by employing the method of Lyapunov functional. More specifically, the uninfected equilibrium is globally asymptotically stable if R₀?1, an infected equilibrium without immune response is globally asymptotically stable if R₁?1<R₀ and an infected equilibrium with immune response is globally asymptotically stable if R₁>1. The immune activation has a positive role in the reduction of the infection cells and the increasing of the uninfected cells if R₁>1.     

A hybrid quantum-inspired immune algorithm for multiobjective optimization

This study suggests a novel quantum immune algorithm for finding Pareto-optimal solutions to multiobjective optimization problems based on quantum computing and immune system. In the proposed algorithm, there are distinct characteristics as follows. First, the encoding method is based on Q-bit representation, and thus a chaos-based approach is suggested to initialize the population. Second, a new chaos-based rotation gate and Q-gates are presented to perform mutation and improve the quality of the population, respectively. Finally, especially, a new truncation algorithm with similar individuals (TASI) is utilized to preserve the diversity of the population. Also, a new selection operator is proposed to create the new population based on TASI. Simulation results on six standard problems (ZDT6, CP, SP, VNT, OSY and KIT) show the proposed algorithm is able to find a much better spread of solutions and has better convergence near the true Pareto-optimal front compared to the vector immune algorithm (VIS) and the elitist non-dominated sorting genetic system (NSGA-II).     

Rapid analysis of multicomponent pesticide mixture by GC-MS with the aid of chemometric resolution

Applications of hyphenated chromatographic techniques, especially GC-MS technique, have been reported in chemical, biological, environmental, agricultural and medical analysis. The complexity of the samples in these fields is still an obstacle for the technique to be practical and the overlapping of the multicomponent signals induces chemometric methods widely employed. In this work, taking the rapid analysis of pesticide mixture as an example, a chemometric approach was proposed for resolution of multicomponent overlapping GC-MS signal. In the method, a mass spectral library of pesticides was organized at first, then target factor analysis (TFA) was employed for testing the existence of a specific pesticide in the multicomponent overlapping GC-MS signal, and finally the chromatographic information of the pesticide was extracted by a non-negative immune algorithm (IA). A GC-MS signal of a 40-component pesticide mixture eluted within 9 min was analyzed by the method. It was found that the mass spectra and chromatographic profiles of almost all the pesticides can be obtained.     

一类具有时滞的病菌-免疫力模型的Hopf分歧

考虑病菌的一种信息交流机制,建立一类病菌与免疫系统竞争的时滞传染病模型.分析正平衡点的存在性、渐近稳定性、Hopf分歧的存在性及方向.运用计算机数值模拟验证所得理论结果,为传染病的控制和预防提供了理论基础和数值依据.     

Stability and Hopf bifurcation in a viral infection model with nonlinear incidence rate and delayed immune response

A viral infection model with nonlinear incidence rate and delayed immune response is investigated. It is shown that if the basic reproduction ratio of the virus is less than unity, the infection-free equilibrium is globally asymptotically stable. By analyzing the characteristic equation, the local stability of the chronic infection equilibrium of the system is discussed. Furthermore, the existence of Hopf bifurcations at the chronic infection equilibrium is also studied. By means of an iteration technique, sufficient conditions are obtained for the global attractiveness of the chronic infection equilibrium. Numerical simulations are carried out to illustrate the main results.     

免疫算法用于复杂样品的GC-MS快速分析

建立了一种基于免疫算法的复杂样品气相色谱-质谱联用(GC-MS)快速分析方法, 该方法采用快速温度程序测定复杂样品的GC-MS信号, 再通过快速解析得到各组分的信息. 计算过程中, 采用各种可能存在于混合物中的组分质谱作为算法的输入, 按照保留时间的顺序逐一对重叠的质谱信号进行解析, 得到各组分的色谱信息. 对于混合物中实际存在的组分可得到该组分的色谱流出曲线, 而对于混合物中不存在的组分所得色谱流出曲线几乎为零. 采用所建立的方法对含有16个组分的有机磷农药混合物进行了分析, 在保留时间10 min内得到了所有组分的色谱信息.     

血小板相关抗体及膜糖蛋白检测在免疫性血小板减少症患者诊断中的价值

目的探讨血小板表面血小板相关抗体(血小板相关免疫球蛋白)及血小板膜糖蛋白在免疫性血小板减少症中的诊断及预后评价应用价值.方法采用流式细胞术(FCM)测定了70例血小板减少症患者及20名正常人血小板表面血小板相关免疫球蛋白(PAIgG)及血小板膜糖蛋白(CD61,CD41,GPIIb/IIIa).结果初治30例特发性血小板减少性紫癜(ITP)患者中血小板相关抗体PAIgG在血小板表面阳性百分率均高于正常对照组(P<0.01),血小板膜糖蛋白均低于正常对照组(P<0.01);20例经激素治疗的ITP患者PAIgG与正常对照组相比差异无统计学意义(P>0.01),血小板膜糖蛋白与正常对照组相比差异无统计学意义(P>0.01);继发性血小板减少症患者(慢性再生障碍性贫血、白血病、类风湿关节炎)血小板相关抗体在血小板表面阳性百分率均高于正常对照组(P<0.01),血小板膜糖蛋白均低于正常对照组(P<0.01);20例治疗有效患者治疗后血小板相关抗体较治疗前下降(P<0.01),血小板膜糖蛋白上升,其差异有统计学意义(P<0.01).结论 FCM用于免疫性血小板减少症患者的血小板相关抗体及血小板膜糖蛋白检测,具有灵敏、快速、简便的特点,是适用于临床诊断的新方法,对免疫性血小板减少症的诊断及疗效观察有较好的实用价值.     

糖芯片的检测及应用

糖芯片技术具有样品少、通量高和特异性强等优点,是一种糖组学研究的新的技术平台和强大的分析工具,已经广泛用于糖和蛋白质的特异性作用、酶活性和抑制剂、病毒入侵机理、细菌检测和免疫反应等方面的研究.本文简要介绍了糖芯片的原理、制备和信号的检测技术(荧光标记法、质谱法、SPR法等),分析了糖芯片在各个领域的应用及其发展前景.