基于定向突变的自适应并行免疫算法

针对克隆选择算法收敛速度较慢的问题,对算法策略进行研究,提出了一种基于定向突变的自适应并行免疫算法(APIA)。该算法采用自适应并行搜索策略,在记忆库中引入定向突变算子,增强算法的局部定向搜索能力,并改善算法早熟的问题。同时算法还改进了超变异算子,以提高其运行效率。仿真实验结果表明:该算法比克隆选择算法和传统的遗传算法有更好的寻优能力,有效地提高了收敛速度,缩短了搜索时间。     

用IAA求解约束模型多解问题

针对蚁群优化算法易于陷入早熟收敛和局部求精能力不足的缺点,提出一种用免疫蚁群算法(IAA)寻找最优解的方法.算法基于人工免疫系统原理,设计了具有免疫能力的蚂蚁抗体保持蚁群的多样性,在迭代后期蚁群依然保持进化能力,提高了算法的局部求精能力,使蚁群优化算法在局部开采与全局探索间都取得了更好的平衡.实验结果表明,算法具有良好的优化性能和时间性能.     

具有免疫体亲近性的遗传算法及其应用

遗传算法处理具有离散变量的优化问题及网络问题是比较有效的，但在此算法时，容易产生限于局部的最优解，本文根据生物体的免疫体具有亲近性的特征，改进了遗传算法，并应用改进后的算法，求解旅行商问题。     

The development of gene therapy for diseases of the lung

The development of a successful gene therapy has many stages, including preclinical testing in animal models and proof of principle clinical studies. A variety of diseases affect the lung, which are candidates for gene therapy; this review will mainly focus on the diseases that have attracted the most attention and have therefore yielded the most progress, namely lung cancer and the monogenic disorder cystic fibrosis. Knowledge gained from clinical studies could eventually be applied to more complex lung conditions such as acute respiratory distress syndrome and asthma. In addition, increased gene transfer efficiencies could be obtained by appropriate selection of the gene transfer vector and mode of delivery.Received 8 August 2003; received after revision 10 September 2003; accepted 17 September 2003     

Enhanced heparan sulfate proteoglycan-mediated uptake of cell-penetrating peptide-modified liposomes

Protein transduction domains (PTDs) are used to enhance cellular uptake of drugs, proteins, polynucleotides or liposomes. In this study, functionalized Antennapedia (Antp, aa 43–-58) and HIV Tat (aa 47–57) peptides were coupled to small unilamellar liposomes via thiol-maleimide linkage. Modified liposomes showed higher uptake into a panel of cell lines including tumor and dendritic cells than unmodified control liposomes. Liposome uptake was time and concentration dependent as analyzed by flow cytometry and live-cell microscopy. At least 100 PTD molecules per small unilamellar liposome (100 ± 30 nm) were necessary for efficient translocation into cells. Cellular uptake of PTD-modified liposomes was 15- to 25-fold increased compared to unmodified liposomes and was inhibited by preincubation of liposomes with heparin. Glycosaminoglycan-deficient CHO cells showed dramatically reduced cell association of PTD-modified liposomes, confirming the important role of heparan sulfate proteoglycans in PTD-mediated uptake. Antp-liposomes used as carriers of the cytotoxic drug N⁴-octadecyl-1--D-arabinofuranosylcytosine-(5- 5)-3-C-ethinylcytidine showed a reduction of the IC₅₀ by 70% on B16F1 melanoma cells compared with unmodified liposomes. PTD-functionalized liposomes, particularly Antp-liposomes, represent an interesting novel carrier system for enhanced cell-specific delivery of a large variety of liposome-entrapped molecules.Received 16 April 2004; received after revision 13 May 2004; accepted 25 May 2004     

DNA fragmentation in leukocytes following subacute lowdose nerve agent exposure

The objective of the present study was to determine levels of DNA fragmentation in blood leukocytes from guinea pigs by single-cell gel electrophoresis (comet assay) after exposure to the chemical warfare nerve agent (CWNA), soman, at doses ranging from 0.1 LD₅₀ to 0.4 LD₅₀, once per day for either 5 or 10 days. Post-exposure recovery periods ranged from 0 to 17 days. Leukocytes were imaged from each animal, and the images analyzed by computer. Data obtained for exposure to soman demonstrated significant increases in DNA fragmentation in circulating leukocytes in CWNA-treated guinea pigs compared with saline-injected control animals at all doses and time points examined. Notably, significantly increased DNA fragmentation was observed in leukocytes 17 days after cessation of soman exposure. Our findings demonstrate that leukocyte DNA fragmentation assays may provide a sensitive biomarker for low-dose CWNA exposure.Received 29 July 2003; accepted 14 August 2003     

HLA－G inhibits xenogenetic cytotoxicity mediated by human NK cells and T lymphocytes against PECs

In order to investigate whether the non-classical HLA-G class I molecule protects the prcine endothelial cells(PECs)from the lysis mediated by human immune cells in pig to human discordant xenotransplantation,we have cloned HLA-G cDNA from a human placents by RT-PCR.Mammalian expression vector,pEFG-neo,was constructed by insertion of HLA-G cDNA in pEF-neo.We obtained efficiently expressed PECs by stable transfection.Cytotoxicity assay showed that overexpression of HLA-G on PECs was sufficient to inhibit human NK-92 cell lysis.The level of lysis was equal to or less than that of the lysis of human umbilical vein endothelial cells mediated by human NK-92 cells.It also indicated that HLA-G inhibited the lysis of PECs mediated by xeno-antigen specific T lymphocytes.The reduction of lysis ranged between 59.1% and 88.9A%.These findings suggest that the transgenic approach to overexpress HLA-G is believed to be a new immunotherapy in overconing the immune rejections in xenotransplantion,including delayed xenograft rejection and cell-mediated rejection.     

甲亢患者双特异性免疫复合物的研究

采用捕捉法ELISA,检测108例亢患者的抗体／补体类双特异性免疫合（Ig-C3-TCIC）和抗体／抗体类双特异性免疫复合物（Ig/Ig-TCIC),结果发现,甲亢患者除了C3／IgA-tcic含量显著高于健康人,C3／IgM-TCIC与健康人无显著性差异外,IgM/C3-TCIC、IgG/C3-TCIC、IgA/C3-TCIC和C3／IgG－TCIC的含量均显著低于健康人;各类Ig/Ig－含量,除IgA/IgM-TCIC与健康人无显著差异外,其余均显著高于健康人,结果表明,甲亢患者排除“异己”原的能力低下,而免疫调节水平紊乱,从而出现过高的免疫应答,也证明甲亢患者存在整体的和细胞免疫紊乱。     

Protective and immunostimulating activity of a low dose of cyclophosphamide in the experimental infection of mice with foot-and-mouth disease virus

Summary Administration to mice of a low, non-immunosuppressive dose of cyclophosphamide 4 days before infection with foot-and-mouth disease virus decreases viral replication, enhances the immune response against the virus and prevents panceatic damage.