Phosphate-Methylated Oligonucleotides Past, Present and Future

At the moment, we see a great interest for application of Anti Sense Oligonucleotides (ASOs) in order to regulate the expression of genes related to certain diseases. These nucleotides obtained a number of fascinating properties by means of chemical manipulation of natural DNA and RNA under conservation of Watson-Crick base-pairing. About 35 years ago for our research in this field, we selected synthetically (short) phosphate-methylated DNA and RNA. It was concluded that there is an exclusive selection in hybridization affinity with natural DNA and RNA. These (bio)chemical and physical-chemical properties are extensively published. ASOs have found their way in public health as is clearly shown in the treatment of (progressive) neurological diseases. We focus specifically on the past, present and future of the phosphate-methylated oligonucleotides, illustrated with different research studies in chemistry and biophysics. A new field of application of modified DNAs is based on interactive improvements of sensitivity and specificity of nanowire field effect transistor gene chip by designing phosphate-methylated DNA as probe.

Inhibitory Effects of Anti-sense PTTG on Malignant Phenotype of Human Ovarian Carcinoma Cell Line SK-OV-3

To construct eukaryotic expression vector expressing full length anti-sense pituitary tumor transforming gene (PTTG) mRNA and observe its blocking effect on the potential invasion of human ovarian carcinoma cell line SK-OV-3. PCR primers containing designed enzyme cut sites were used for cloning full-length PTTG gene fragment, and the resulting PCR product was inserted into the eukaryotic vector pcDNA3.1 in the antisense direction. The recombinant vector was then transfected into SK-OV-3 by Lipofectamine. The positive cell clone was screened by G418, PTTG and bFGF at protein level expression were detected by Western blot. The biological behavior change of transfection positive cells was observed by colony formation in soft agar assay. Our results showed that SK-OV-3 clones stably expressing full-length recombinant pcDNA3.1-PTTGas were obtained. The expressions of PTTG and bFGF protein in transfected cells were decreased by 61.5 % and 52.3%, respectively as compared with non-transfected ones. The number of colony formation was reduced significantly in transfected cells as compared with empty vector transfected and non-transfected cells. It is concluded that the recombinant vector pcDNA3.1-PTTGas is a novel tool and provides an alternative anti-sense gene therapy targeted at PTTG in human carcinoma.

Fusions of Dendritic Cells and C6 Cells Transfected with TGF-β1 Antisense in Treatment of Intracranial Gliomas

Objective： To investigate the immunotherapy efficacy of fusion cells （dendritic-C6anti-TGF-β1 cells） in the treatment of intraeranial gliomas. Methods： Dendritic cells were isolated from rat bone-marrow precursors stimulated in vitro with granuloeyte-macrophage colony-stimulating factor （GM-CSF） and Interleukin-4 （IL-4）. C6anti-TGF-β1 cells originally from C6 cell line of a rat glioblastoma were transfected with plasmid of TGF-β1 anti-sense gene. Fusions of dendritic cells and C6anti-TGF-β1 cells were prepared by polyethylene glycol （PEG）. The DC/C6anti-TGF-β1 fusion cells were observed and confirmed by fight microscopy and scanning electron microscopy. Experimental rats were divided into three groups at random： C6 cells （Ⅰ）, dendritic-C6anti-TGF-β1 fusion cells and C6 cells （Ⅱ） and IMDM medium only （Ⅲ）. The cells were injected into right parietal lobe region of the rat with stereotaxic technique. Histology, tumor necrosis and survival time were evaluated. Results： Compared with the rats that received C6 cells （survival median time was less than 20 days, tumor region was seen in all fields of observed）, the rats injected with dendritic-C6anti-TGF-β1 fusion cells and C6 cells got a more prolonged life span （more than 59 days）, as well as less tumor region （5.01%-6.2%）. There was no tumor necrosis, but some glias were seen in surroundings. All rats were survived and no necrosis was observed in negative control group. Statistical analysis showed that group Ⅱ had significant difference compared with group Ⅰ. Conclusions： Dendritic-C6anti-TGF-β1 fusion cells could prolong the life span of rats, providing a strategy to achieve an antitumor response against tumors in the central nervous system.

Integrating Aster Images Processing and Fieldwork for Identification of Hydrothermal Alteration Zones at the Oumjrane-Boukerzia District, Moroccan Anti-Atlas

Mapping from remote sensing has become more effective in the field of geology, mainly in lithological discrimination and identification of hydrothermal alteration zones. The use of this technique consists in obtaining information about the rock mass and the main ones existing in the inaccessible areas. Satellite data from the ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) sensor represent a favorable potential for detecting the spectral signatures of mineral zones and identifying their nature. These data are more reliable in places where the climate is arid with less abundant vegetation, as at the Oumjrane-Boukerzia mining district. This region which is part of the Eastern Anti-Atlas, is composed of several mineralized veins which still require detailed studies and exploration by the technique of remote sensing. In this work we applied several processing techniques on ASTER imagery such as Colored Composition, Principal Component Analysis and Ratio Bands. The use of the reports of the specialized Bands makes it possible to identify some hydrothermal alteration minerals within the mining district of Oumjrane Boukerzia. These minerals are represented mainly by iron oxides and hydroxides (Hematite, jarosite, limonite and goethite), carbonate minerals (dolomite, calcite), clay minerals (Illite, kaolinite and chlorite) and quartz minerals. This work allows us to produce a map of hydrothermal alteration zones which can be used as a valuable reference in the strategy of mining exploration for the base metals (Cu, Pb, Zn and Ba), in the mining district of Oumjrane-Boukerzia and in the entire Eastern Anti-Atlas.

Anti-Biofilm, Anti-Quorum Sensing, and Anti-Proliferative Activities of Methanolic and Aqueous Roots Extracts of Carica papaya L. and Cocos nucifera L.

Objective: This study focused on the antibacterial and anti-proliferative activity of extracts from Carica papaya and Cocos nucifera roots. Methodology: The minimum inhibitory concentration and the minimum bactericidal concentration of the extracts on Escherichia coli, Pseudomonas aeruginosa, Streptococcus mutans, and Staphylococcus aureus were deduced by the microdilution method. The anti-biofilm activity was determined on all four strains and anti-quorum sensing activity by inhibition of violacein production in Chromobacterium violaceum. Anti-proliferative activity on prostate cultured cancer cells was evaluated by MTT assay. Sterols and triterpenes were also assayed in this study. Results: The methanolic extract of Carica papaya showed the best anti-biofilm effect with a percentage inhibition of 66.10 ± 1.79. The methanolic extract of Cocos nucifera had the strongest inhibition on the production of quorum sensing (61.42 ± 0.28). In addition, the methanolic extract of Cocos nucifera roots showed the best cytotoxic effect on prostate cancer LNCaP cell lines (IC50 = 26.98 ± 2.6 μg/mL) and Carica papaya on the PC-3 lines (IC50 = 127.20 ± 5.99 μg/mL). The extracts were also rich in triterpenes and sterols. Conclusion: This study provides support for the ethnomedical use of Carica papaya and Cocos nucifera roots as an antimicrobial and anticancer.

基于PEGPEA-高灵敏仿生光子晶体薄膜制备及应用

采用乳液聚合结合改良的Stӧber方法制备了单分散聚苯乙烯(PS)@SiO2核壳纳米微球,然后将其分散在聚(乙二醇)苯基醚丙烯酸酯(PEGPEA)中,形成非密集颗粒阵列后快速光聚合捕获规则阵列,制备了一种机械变色的光子晶体薄膜。采用SEM、光纤耦合光谱仪对光子晶体薄膜进行了表征,考察了PS@SiO2核壳纳米微球体积分数和粒径对光子晶体薄膜结构色的影响,并对光子晶体薄膜的力致变色机理进行了推测。结果表明,热处理改善了PS@SiO2核壳纳米微球的微观秩序,加快形成蛋白石光子晶体结构;光子晶体薄膜结构色随着PS@SiO2核壳纳米微球体积分数的增加或粒径的减小由红色向蓝色渐变;光子晶体薄膜具有的结构色反射率>60%、拉伸应变至少可达70%、灵敏度2.16 nm/%、响应速度1.9 nm/ms,反射波长调谐范围为151 nm;在100次拉伸/释放循环实验和25℃下维持拉伸状态3 d,恢复后光子晶体薄膜结构色保持不变。

砼结构抗滑桩微形变监测系统的设计与应用

研究砼结构抗滑桩微形变监测系统,对多通道高压激振、拾振等采集电路模块进行设计,提出了“风光互补”的供电和数据的本地、远端冗余存储的系统可靠性保障方案,在内蒙古某露天铁矿边坡滑坡治理工程中的砼结构抗滑桩健康监测应用表明,本文提出的砼结构抗滑桩微形变监测系统能稳定可靠地对砼结构抗滑桩的应力、形变等进行监测,提高了砼结构抗滑桩监测的实时性和科学性。

Anti-miR-155反义寡核苷酸对肺腺癌A549细胞增殖的影响

目的观察anti-miR-155反义寡核苷酸(AMOs)对肺腺癌A549细胞增殖的影响。方法 A549细胞分为对照组和AMOs处理组,采用AMOs抑制A549细胞内miR-155的活性,液闪计数仪测定[3H]-TdR掺入量,MTT法测定细胞增殖抑制率,流式细胞仪测定细胞周期。结果与对照组相比,AMOs显著减少A549细胞[3H]-TdR掺入量,随着浓度从10nmol/L逐渐增加至100nmol/L,A549细胞[3H]-TdR掺入量亦随之减少。MTT法测定细胞增殖抑制率结果显示,与对照组相比,AMOs显著抑制A549细胞的增殖。流式细胞术检测结果显示AMOs使G0/G1细胞比例显著增加,G2/M期细胞比例显著减少。结论采用AMOs抑制A549细胞内高水平表达miR-155的活性后,可显著抑制A549细胞的增殖。

溶剂依赖型碳点的制备及水含量检测和防伪应用

以二苯氨基-4-苯甲醛和邻苯二胺为前驱体,乙醇为溶剂,采用溶剂热法合成了具有高量子产率(QY=87.76%)的氮掺杂荧光碳点(N-CDs)。通过对有机溶剂和水溶液中N-CDs光学性质的考察,表明N-CDs具有良好的溶剂依赖性和化学稳定性。水的加入在N-CDs中构建氢键网格,从而实现了发射波长的红移,N-CDs溶液由蓝色变为黄色。进一步,基于N-CDs荧光试纸蓝色到黄色的可逆颜色变化,制备便携的空气湿度可视化检测试纸。此外,N-CDs还可用于荧光墨水、书写纸和荧光柔性薄膜,拓展了其在信息传递,高级防伪加密和固态荧光的应用。

Anti-miR-155反义寡核苷酸对人肺鳞癌H157细胞增殖的影响

目的:观察anti-miR-155反义寡核苷酸(AMOs)对肺鳞癌H157细胞增殖的影响。方法:将H157细胞分为对照组和AMOs处理组,AMOs处理组采用AMOs抑制H157细胞内miR-155的活性,液闪计数仪测定[3H]-TdR掺入量,MTT法测定细胞增殖抑制率,流式细胞仪测定细胞周期。结果:与对照组相比,AMOs显著减少H157细胞[3H]-TdR掺入量(P<0.01),随着浓度从10 nmol/L逐渐增加至于100 nmol/L,H157细胞[3H]-TdR掺入量亦随之减少(P<0.01);AMOs显著抑制H157细胞的增殖(P<0.01),使G0/G1细胞比例显著增加,G2/M期细胞比例显著减少(P<0.01)。结论:AMOs通过抑制H157细胞内高水平表达miR-155的活性,显著抑制H157细胞的增殖。

Anti-miR-155反义寡核苷酸对A549细胞Wee1表达的影响

目的观察anti-miR-155反义寡核苷酸(AMOs)对A549细胞Wee1表达的影响。方法采用特异性anti-miR-155反义寡核苷酸抑制A549细胞内成熟miR-155的活性,realtime quantitive RT-PCR测定Wee1mRNA表达量,Western blot测定Wee1蛋白和Phospho-cdc2(Tyr15)蛋白的表达量。结果 100nmol/L浓度的AMOs处理的A549细胞中Wee1mRNA表达量与对照组A549细胞中Wee1mRNA表达量相比无显著性差异(P>0.05);与对照组相比,100nmol/L浓度的AMOs处理的A549细胞Wee1蛋白和Phospho-cdc2(Tyr15)蛋白的表达量显著增加(P<0.05)。结论采用AMOs抑制A549细胞内高水平表达miR-155活性后,可显著增强Wee1蛋白的表达。

海南红树林底泥海洋放线菌的抗菌及抗群体感应活性筛选

采用滤纸片法以紫色色杆菌、大肠杆菌和金黄色葡萄球菌等为指示菌对84株分离自红树林底泥的海洋放线菌进行抗菌及抗群体感应活性筛选,再对高活性菌株进行活性复筛以及薄层层析化学多样性分析。结果显示,菌株HN2-56具有很强的抗群体感应活性及较弱的抗菌活性,且代谢产物较为丰富。对该菌的代谢产物进行初步分离及GC-MS分析,从其活性组分中鉴定出13个可能的化合物,且多个化合物具有一定的生物活性。活性验证试验发现,化合物4(二乙基甲苯甲酰胺)和12(莪术烯醇)具有抗群体感应活性。经16S rDNA序列分析,结合形态观察和系统发育分析,将菌株HN2-56鉴定为链霉菌(Streptomyces chumphonesis)。该菌株在抗群体感应方面有一定的应用潜力,具有进一步研究的价值。

FPM DOFS中stokes或anti-stokes的频移分析

近年来分布式光纤传感器（DOFS）发展很快，利用四波混频脉冲移位的分布式光纤传感器（FPMDOFS）是最近提出的一种新型分布式光纤传感技术，本文对FPMDOFS中stokes／anti－stokes频移进行了理论分析，给出频移计算公式，并指出在激励光脉冲功率衰减较大的情况下，应考虑由自相位调制引起的stokes／anti－stokes中心频率偏移。

基于纤维素膜的聚乙烯醇基抗溶胀水凝胶柔性传感材料的制备及性能研究

目前,基于水凝胶的柔性可穿戴传感器受到了人们广泛的关注。然而传统的水凝胶在水环境中的膨胀,限制了其应用。文中以聚乙烯醇(PVA)为基体,通过缩醛反应将4-乙炔基苯甲醛引入网络中,成功地制备了具有良好力学性能的抗溶胀水凝胶。该水凝胶通过破坏PVA分子链与水分子之间的氢键,降低溶胀的驱动力,π-π堆积增强链间相互作用减小孔隙度,抵抗水分子的渗透,使得溶胀率维持在5%。同时网络交联密度增加,改善了分子链间的间距,赋予水凝胶更高的韧性(断裂应力=1.4 MPa,断裂伸长率=528%)。考虑到生物相容性以及水环境的应用,使用无毒纤维素膜与水凝胶构建出一种用于人体动作监测的柔性应变传感器,拓展了可穿戴电子设备的潜在应用。

感知示能与沉浸体验:重庆抗战遗迹的数字活化设计

重庆抗战遗迹是中国抗战历史的见证和缩影,随着时间推移,其保存方式和宣传路径面临新的挑战和机遇。信息时代下,文化遗迹的保护和传播方式正从传统的陈列展示转变为交流互通、数字储存、体验沉浸等新媒介传播路径。研究以大轰炸纪念碑为个案,利用点云数字技术的处理方式,复刻文化遗迹,并基于感知示能性理论叙事框架分析了该数字作品的交互创新,探究操作行为、视觉导向、文化语境对数字产品活化设计的影响。从物理感知到文化感知共6个维度的示能性分别对其功能定位、表达形式和交互体验起着不同程度的作用,深入理解并合理运用该相关规律来开展实践将发掘出新的可能。

基于双波长光电传感的抗干扰烟雾报警器研究

推动火灾探测报警器的技术升级,对于保障人民群众生命财产安全具有重大意义。目前,主流独立式感烟火灾探测装置由于依赖单频光谱与烟雾作用信息进行火灾报警,存在抗干扰能力差、灵敏度低等问题。基于球形粒子的Mie散射理论,提出了一种改进的双波长烟雾检测方法,通过抗干扰逻辑运算测量散射光差异来减少误报。该方法提高了光电传感装置对非火灾因素的抗干扰性,具备优异的抗灰尘、抗水雾干扰能力以及火灾信息探测的高灵敏度,对火灾烟雾的灵敏度达到0.21 dB/m。在饱和烟雾浓度下,探测器烟雾响应时间约3 s,实现快速响应烟雾能力。

“眼前”反腐工作成效与民众“心中”的反腐获得感——作用逻辑与实证分析

腐败治理工作成效是影响民众获得感的关键性所在,外部反腐成效如何具体影响和转化为民众反腐获得感,已成为亟需回答的现实命题。通过构建“反腐工作成效—民众反腐获得感”的理论分析框架,并基于实证数据对反腐工作成效与民众反腐获得感之间的作用机制进行分析,发现腐败治理的“客观状况”对民众反腐获得感产生了显著的积极影响,尤其是加大反腐力度会对民众反腐获得感提升起到促进作用,差异化的廉洁价值观念更是会影响反腐工作的整体效应。而且,纵深推进反腐工作能够提升民众社会经济地位并改善民众的公平感知,有助于提升政府民生服务回应力,进而起到保障和增强民众反腐获得感的现实作用。因此,为进一步保障和提升民众反腐获得感,政府须着力解决好人民群众身边的微腐败问题,以民众的实际需求为抓手,精准化反腐工作“供给”,保障民生事业有序开展,全面提升政府廉能工作质量。

基于深度监督隐空间构建的语义分割改进方法

现有卷积操作在语义分割任务中难以有效捕捉长距离区域间的关系,导致分割结果不符合人类常识。为此,提出一种基于深度监督隐空间构建的语义分割改进方法。采用“特征图-隐空间-特征图”流程,将图像空间的像素特征转换为隐空间中的节点特征,将区域之间的位置和语义关系转换为节点之间的连接权重,实现了从特征图到隐空间的特征转换。在隐空间构建过程中,使用Kullback-Leibler散度损失函数监督投影矩阵,以避免从特征图到隐空间节点的转换过程中丢失特征;使用InfoNCE损失函数监督节点特征表征与真实标签表征,使得图像特征与标签保持一致。该方法在构建的隐空间上使用图神经网络进行语义推理,学习节点之间的关系,赋予模型学习区域间语义关系的能力,从而改善分割结果中的反常识现象。在公开数据集CityScapes上的实验结果表明,相比基线分割网络,该方法的平均交并比(mIoU)为81.1%,相较于基线分割网络mIoU提升2.6个百分点,能有效提升分割结果。

基于调频率微调的压缩感知ISAR抗欺骗干扰技术研究

有源欺骗干扰是针对逆合成孔径雷达(ISAR)的一种较成熟的干扰技术,但抗欺骗干扰技术研究尚有欠缺。文中在分析欺骗干扰信号生成原理的基础上,采用脉间调频率微调的方法,使得虚假目标信号与雷达解线频调脉压参考信号的调频率失配,以降低虚假目标的脉压增益。但由于调频率脉间随机变化,会造成成像积累时间内不同调频率回波信号无法相参积累,难以进行方位向高分辨成像的问题。为解决这个问题,提出了采用压缩感知技术,对调频率相同的稀疏回波进行信号重构,以获取真实目标的ISAR图像。此外,利用干扰信号调频率失配时的距离像特性,文中还提出基于距离像熵值的智能化干扰感知方法,能够准确判断雷达是否遭受干扰,为雷达决策采用抗干扰工作模式提供依据。仿真结果表明所提方法可以准确感知干扰,能够在有源欺骗干扰情况下抑制假目标回波,得到真实目标清晰的ISAR像。

基于频谱特征和LSTM融合的智能抗干扰技术优化

提出一种基于频谱特征和深度学习的抗干扰通信技术。将基于频谱感知的信号特征识别方法与基于LSTM的无线通信信号特征预测方法相结合,进行目标通信系统发射信号特征参数集获取和预测;最终生成并发射与目标通信系统发射信号具有相同特征参数的干扰信号,以进行目标通信系统有效干扰。实验结果表明,当训练数据量占比为40%时,基于LSTM信号特征预测方法的预测准确率最高为99.9%。对比于传统的感知跟踪干扰方案,本方法可有效降低接收机感知速度,提升发射机敏捷度。提出的抗干扰通信技术的信号干扰成功率可高达86%。