复杂网络上带有直接免疫的SIRS类传染模型研究

在SIRS(susceptible-infected-removed-susceptible)模型基础上,提出一个带有直接免疫的SIRS类传染模型.利用平均场理论,分析得到该传播模型的传染临界阈值主要与网络拓扑结构、直接免疫速率和免疫丧失速率有关.理论分析和数值仿真表明,直接免疫作用可以增大复杂网络上疾病传播的临界阈值、降低传染性疾病的传播范围,从而有效控制疾病在复杂网络上传播.     

一种基于动态偏好扫描的网络免疫策略

复杂网络中各种自组织现象的涌现给网络脆弱性挖掘和网络免疫自推进带来了启示.一个完整的免疫资源配置过程可以分为4个阶段：信息收集、扫描、漏洞修复和自我推进.网络主机脆弱性分布的实证分析表明,脆弱主机在网络中呈现明显的幂律分布特性,这就意味着盲目扫描将耗费大量资源在非脆弱或不存在的主机上,而一个有效的网络免疫策略应该利用这种非均匀的网络脆弱性分布特性.静态偏好性的扫描方法在初期能取得良好的推进效果,但并不能将这种有效性贯穿整个免疫过程.为此,提出了一种新的基于扫描方式的网络免疫自推进策略.该策略能够在不知道网络结构的条件下,通过一种动态适应的偏好扫描方法,高效命中脆弱主机实施免疫修复.经过传播模型推导及计算机仿真分析,设计的网络免疫策略能够很好地抑制危害传播,提高网络的安全性.     

基于两阶段免疫接种的SIRS计算机病毒传播模型

针对现有的带有免疫接种策略的病毒传播模型的不足,根据生物学中的传染病模型提出了带有阶段免疫接种特点的SIRS计算机病毒传播模型。该模型充分考虑了在达到感染阈值时免疫接种概率的变化对于病毒传播的影响。此外,利用动力学稳定性理论分析并证明了病毒平衡点的存在和稳定条件。数值仿真结果表明,提高免疫接种率和设定适当的感染阈值可以有效控制计算机病毒在网络中的传播。     

基于人工免疫算法的车辆控制模型研究

对于自动驾驶中的车辆跟踪控制,仅依靠传统的控制策略进行速度调节无法达到准确、快速的跟踪效果。将免疫学原理中的人工免疫算法引入到车辆控制中,并建立了车辆横向和纵向的控制模型,以达到改善车辆控制的效果。通过大量仿真实验,验证免疫算法在车辆控制过程中的优劣。仿真结果表明,该控制系统在被控对象参数变化的情况下,仍具有良好的控制性能,具备了很强的自适应性和鲁棒性,能够迅速适应外界变化,具有较大的工程应用价值。     

大鲵皮胶原蛋白肽的抗原反应特性研究

目的 探讨用酶法提取大鲵皮胶原蛋白肽,并确定大鲵皮胶原蛋白肽的抗原性,为进一步研究大鲵皮胶原蛋白肽的生物相容性提供依据。方法 采用酶法提取获得大鲵皮胶原蛋白肽,并对得到的胶原蛋白肽进行基质辅助激光解吸电离飞行时间质谱（MALDI-TOF-MS）分析确定其分子量分布范围。将得到的胶原蛋白肽与弗氏佐剂混合乳化后经免疫程序免疫ICR小鼠,采用抗体酶联免疫试剂盒检测小鼠血清中IgG、IgA、IgM以及IgE含量。结果 所得到的大鲵皮胶原蛋白为I型胶原蛋白,酶解后的胶原蛋白肽分子量均小于10 kDa,多数肽分子量集中在2000~5000 m/z,检测血清中IgA、IgG、IgM和IgE 4种免疫球蛋白的浓度范围分别是71.63~85.90 μg/mL、705.19~857.04 ng/mL、71.63~85.90 ng/mL与224.54~261.0 μg/mL。结论 大鲵皮胶原蛋白肽对ICR小鼠呈现出较弱的抗原性。     

Immunization with Genetically Modified Trypanosomes Provides Protection against Transmissible Spongiform Encephalopathies

Transmissible spongiform encephalopathies are incurable neurodegenerative diseases, associated with the conversion of the physiological prion protein to its disease-associated counterpart. Even though immunization against transmissible spongiform encephalopathies has shown great potential, immune tolerance effects impede the use of active immunization protocols for successful prophylaxis. In this study, we evaluate the use of trypanosomes as biological platforms for the presentation of a prion antigenic peptide to the host immune system. Using the engineered trypanosomes in an immunization protocol without the use of adjuvants led to the development of a humoral immune response against the prion protein in wild type mice, without the appearance of adverse reactions. The immune reaction elicited with this protocol displayed in vitro therapeutic potential and was further evaluated in a bioassay where immunized mice were partially protected in a representative murine model of prion diseases. Further studies are underway to better characterize the immune reaction and optimize the immunization protocol.     

Passive Immunization Through Avian Egg Antibodies

Oral administration of specific antibodies is an attractive approach to establish passive immunization against various pathogens in humans and animals. Egg yolk contains over 100 mg of IgY per egg and is considered to be a more hygienic and economical source of antibodies, than antibodies from mammalian sera. Recently, considerable research has focussed on the use of IgY as an alternative to mammalian antibodies for several applications, most notably for oral passive immunization against various bacteria and viruses. Oral administration of IgY has proven to be successful for the treatment of a variety of gastrointestinal (GI) pathogens such as bovine and human rotaviruses, bovine coronavirus, Yersinia ruckeri, enterotoxigenic Escherichia coli, Salmonella spp., Edwardsiella, Staphylococcus, and Pseudomonas. Recent advances in hybridoma technology, for the production of monoclonal IgY, also present many benefits for its universal application. IgY technology has significant future opportunities for the design of strategies for the prevention and treatment of infectious gastrointestinal diseases in humans and animals.     

Reducing infant immunization distress through distraction.

Infant procedural distress is largely understudied, and there is a dearth of empirically supported interventions in the child health psychology literature. This study examined nurse-directed distraction for reducing infant immunization distress. Ninety infants and their parents were randomly assigned to a distraction condition (i.e., nurses used stimuli to divert infants' attention) or a typical care condition. Outcome measures were an observational scale, parent and nurse ratings, and infant heart rate. Results indicated that infants engaged in distraction and that distraction reduced their behavioral distress; however, ratings and heart rate were inconclusive. Analyses of procedural phases indicated that infants exhibited elevated distress immediately prior to and during an injection, but this distress was fleeting. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

基于富人俱乐部特性的搜索免疫

为了使用更少的免疫数量且能更快地消灭病毒,已经提出了很多种免疫策略。熟人免疫策略是局域免疫中最有效的方法。基于BA无标度网络的富人俱乐部特性和广度搜索策略,提出了基于富人俱乐部特性的搜索免疫(RPBSI)。该免疫算法有两种策略,这两种策略对邻居节点的搜索方法不同,免疫的代价也有所差异。实验采用SIS病毒传播模型分别在BA无标度网络和科研合作网中验证:RPBSI算法与熟人免疫算法相比可以通过免疫较小的一部分节点达到消灭病毒的目的。     

重组大肠杆菌不耐热肠毒素B亚单位表达条件的优化及其佐剂作用

目的优化重组大肠杆菌不耐热肠毒素B亚单位(LTB)的表达条件,并检测其黏膜佐剂作用。方法通过向LB培养基中添加葡萄糖(终浓度为0.5%)、低温培养诱导等方法诱导LTB的表达;采用阳离子交换法对目的蛋白进行纯化;以LTB作为佐剂进行免疫试验。结果可溶性重组大肠杆菌不耐热肠毒素(LTB)的表达量明显提高,纯化后蛋白含量达95%以上,经纯化的LTB作为三价流感裂解疫苗或gD抗原的佐剂免疫BALB/c小鼠,可提高小鼠血清及黏膜的抗体水平,且其效果与铝化剂及福氏佐剂相当或更高。结论优化了LTB的表达条件,且表达的LTB具有较强的黏膜免疫佐剂作用。