一种基于ARG的肺结节良恶性度判定方法

基于CT影像的肺结节的良恶性识别是肺癌诊断的重要环节，针对这一问题，提出一种基于属性关系图(attributed relational graph， ARG)的肺结节良恶性度判定方法.该方法以肺结节CT图像块作为输入，利用ARG构建其特征结构，并从大量ARGs中挖掘与或图(and-or graph， AoG)作为肺结节类别识别模板，即肺结节良恶性度判定的依据.此外，为提高模板挖掘效率，该方法利用马尔可夫毯(Markov blanket， MB)发现算法去除图像中的冗余特征，降低ARG节点数量.实验结果表明，该方法对恶性肺结节的识别率达到90.12%，能够帮助正确、快速辨识与分析肺结节良恶性，具有一定的实用价值.     

人源性14-3-3σ真核表达载体的构建及鉴定

目的：构建人源性14-3-3σ真核表达载体pCMV-Myc-SFN,并观察其在真核细胞中的表达。方法：通过反转录-聚合酶链反应从HeLa细胞（人宫颈癌细胞系）中获得编码14-3-3σ的cDNA,定向克隆至真核表达载体pCMV-Myc中,经酶切和测序鉴定正确后,应用脂质体法转染HeLa细胞,并通过蛋白免疫印迹法检测细胞内14-3-3σ的表达。结果：构建了真核表达载体pCMV-Myc-SFN,将其转染HeLa细胞48h后,蛋白免疫印迹法检测到细胞内14-3-3σ的表达显著增高。结论：成功构建了真核表达载体pCMV-Myc-SFN,为研究14-3-3σ在上皮细胞源性肿瘤中的作用奠定了基础。     

Survival of docetaxel-resistant prostate cancer cells in vitro depends on phenotype alterations and continuity of drug exposure

We evaluated in vitro the effect of paclitaxel and docetaxel on PC-3 and DU-145 prostate cancer cell lines to understand better the downstream events in drug-induced tumor cell death. Taxane treatments of DU-145 cells induced rapid cell death by apoptosis, but in PC-3 cells, treatments achieved growth arrest, followed by extensive karyokinesis resulting in multinucleation, giant-cell formation and delayed cell death. To determine if the giant multinucleated cells were able to produce proliferating and drug-resistant survivors, we first delineated the kinetics of drug activity and cytotoxic dose range. Analysis of both lines by colorimetric and cell viability assays demonstrated improved cytotoxicity of taxanes applied continuously. Selected doses and schedules of docetaxel were used to induce giant multinucleated cells that gave rise to docetaxel-resistant survivors, which remained sensitive to paclitaxel and other chemotherapeutics. Growth and morphology of the recovered clones was similar to parental cells. The resistant phenotype of these clones determined by immunofluorescence and immunoblot was associated with transient expression of the β-tubulin IV isoform and was independent of P-glycoprotein, bcl-2 and bcl-xL. Resistant clones will be useful to model progression of resistance to taxanes and to identify unknown and clinically important molecular mechanisms of cell death and resistance. Received 15 March 2002; received after revision 25 April 2002; accepted 27 May 2002     

基于表现型共享的多目标粒子群算法研究

在多目标粒子群算法中,粒子的飞行由自身的最优位置和指导粒子决定,如何定义适应度选出合适的指导粒子,指导搜索过程向全局Pareto最优区域飞行,并保持种群在最优前端的多样性是算法的关键问题.针对上述问题,构造了同时考虑粒子的Pareto占优情况和目标空间邻近密集度的表现型共享适应度函数,在此基础上提出一个基于表现型共享的多目标粒子群优化算法(MOPSO).为了验证算法的有效性,采用占优等级指标来分析近似解集的占优情况,并采用EPS、HYP和R2指标来衡量解集的分布情况.实验结果表明,算法具有较强的全局搜索能力,能在较小的计算代价下获得较好的Pareto前端近似.     

两个水稻叶片反向卷曲突变体的表型及遗传分析

为了揭示水稻叶片卷曲的形态建成,分析了水稻Ac/Ds转座子插入突变体库中的2个叶片反向卷曲突变体的表型及组织形态.研究发现,与野生型平展叶片相比,内卷突变体和外卷突变体叶片中泡状细胞数目明显减少,这可能是造成水稻叶片卷曲的重要原因.另外,内卷突变体叶片主脉薄壁细胞少,薄壁细胞崩裂形成的气腔面积较大.对2个卷叶突变体的纤维素含量进行测定发现,内卷突变体叶片及茎杆中纤维素含量明显减少,而外卷突变体叶片及茎杆的纤维素含量与野生型没有显著差异,说明2个卷叶突变体叶片的卷曲可能由不同基因突变造成.分析了2个水稻卷叶突变体的遗传规律,结果表明,二者均由隐性单基因控制.     

基于TCGA数据库分析UHRF1基因在恶性胸膜间皮瘤中的表达及预后意义

利用生物信息学数据库分析泛素样含PHD和环指结构域蛋白1（UHRF1）在恶性胸膜间皮瘤（MPM）中的表达水平及临床意义。基于TCGA数据库和GTEx数据库差异表达分析UHRF1 mRNA在MPM组织和正常肺组织中的表达水平;使用R软件分析UHRF1 mRNA表达量与临床病理参数的相关性;构建Kaplan-Meier模型和单因素多因素COX回归模型分析UHRF1基因在MPM中的预后;利用TIMER2.0数据库分析UHRF1基因与免疫细胞浸润的关系; GSEA分析UHRF1基因发挥功能的主要富集通路。选取8例MPM组织及4例非MPM胸膜组织,通过RT-qPCR的方法验证UHRF1在MPM与非MPM胸膜组织的表达情况。数据库分析结果表明,与正常肺组织相比,UHRF1 mRNA在MPM组织中高表达; UHRF1高表达患者提示MPM患者预后不良;UHRF1基因表达量与CD4⁺辅助型T细胞2、CD4⁺效应记忆性T细胞、巨噬细胞等多种免疫细胞浸润水平具有显著的相关性（P ＜ 0.01）,且显著影响MPM患者的预后。功能富集分析显示,UHRF1主要在DNA复制、蛋白酶体、同源重组等通路中起作用。在收集到的病例样本中,与非MPM胸膜组织相比,UHRF1 mRNA在MPM组织中的表达显著增高（P ＜ 0.001）。UHRF1在MPM组织中高表达,可能通过调节DNA甲基化和免疫细胞浸润来影响MPM患者预后,有望成为MPM治疗和预后评估的潜在靶点。     

SV40 association with human malignancies and mechanisms of tumor immunity by large tumor antigen

SV40 was discovered as a contaminate of poliovirus vaccine lots distributed to millions of individuals in the United States between 1955 and 1963 while contaminated vaccine batches were later circulated worldwide. After SV40 was observed to cause in vitro animal and human cell transformations and in vivo tumor formations in animals, the search for a connection between the virus and human malignancies has continued to the present day. Different molecular methods have been used to detect SV40 gene products in a variety of human cancers, though SV40 causality in these tumor types has yet to be established. These data, however, are not without controversial issues related to inconclusive SV40 serological and epidemiological evidence alongside tools and methodologies that may contribute to false-positive results in human specimens. This review will also explore how vaccination against SV40 protein products may be used to help prevent and treat individuals with SV40-expressing cancers. Received 19 September 2006; received after revision 8 November 2006; accepted 13 December 2006     

一株硅酸盐细菌的表型特征

本实验室从江西南昌一菜园土中分离到一株孢杆菌,通过形态、生理生化等表型特征的鉴定,与文献报道的相近的其它菌株的表型特征比较,认为该 一种硅酸盐细菌,分类属于胶质芽孢杆菌（Ｂａｃｉｌｌｕｓ ｍｕｃｉｌａｇｉｎｏｓｕｓ）。     

量子共振检测仪诊断肿瘤130例

采用量子共振检测仪,通过头发测定了80例恶性肿瘤患者、50例良性肿瘤患者和50例无肿瘤者的免疫功能、肿瘤、恶性肿瘤、良性肿瘤、发锌和病毒感染的代码量价。结果表明：癌症患者的免疫功能明显低于良性肿瘤患者和无肿瘤者（P＜0．001）,而病毒感染程度和发锌的含量明显高于良性肿瘤患者和无肿瘤者（P＜0．001）;恶性肿瘤患者的免疫功能过低、病毒感染程度和发锌含量过高,这些将是诱发癌症的重要因素,也是诱发良性肿瘤的因素。通过对受试者上述指标的检查,将为肿瘤的早期发现和早期诊断提供可靠的依据。     

MRI拉莫尔频率范围内人体不同部位大肠癌组织的介电特性研究

本文利用开端同轴线法,室温下(25 °C),测量了人体不同部位大肠癌组织及对应正常组织在50~500 MHz范围内的介电特性,并依据Cole-Cole模型,利用最小二乘曲线拟合方法,提取癌症组织及对应正常组织的特征参数。统计结果显示在测量频率范围内,不同部位大肠组织的介电特性存在显著性差异（癌症组织电导率除外）。实验结果填补了在MRI拉莫尔频率范围内,大肠癌组织介电特性的研究空白,同时本实验提供不同部位大肠癌组织及对应正常组织的Cole-Cole参数可便于相关科研工作者得到任意频率下相应组织的介电特性。