A Phenylacetamide Resveratrol Derivative Exerts Inhibitory Effects on Breast Cancer Cell Growth

Resveratrol (RSV) is a natural compound that displays several pharmacological properties, including anti-cancer actions. However, its clinical application is limited because of its low solubility and bioavailability. Here, the antiproliferative and anti-inflammatory activity of a series of phenylacetamide RSV derivatives has been evaluated in several cancer cell lines. These derivatives contain a monosubstituted aromatic ring that could mimic the RSV phenolic nucleus and a longer flexible chain that could confer a better stability and bioavailability than RSV. Using MTT assay, we demonstrated that most derivatives exerted antiproliferative effects in almost all of the cancer cell lines tested. Among them, derivative 2, that showed greater bioavailability than RSV, was the most active, particularly against estrogen receptor positive (ER+) MCF7 and estrogen receptor negative (ER-) MDA-MB231 breast cancer cell lines. Moreover, we demonstrated that these derivatives, particularly derivative 2, were able to inhibit NO and ROS synthesis and PGE2 secretion in lipopolysaccharide (LPS)-activated U937 human monocytic cells (derived from a histiocytoma). In order to define the molecular mechanisms underlying the antiproliferative effects of derivative 2, we found that it determined cell cycle arrest at the G1 phase, modified the expression of cell cycle regulatory proteins, and ultimately triggered apoptotic cell death in both breast cancer cell lines. Taken together, these results highlight the studied RSV derivatives, particularly derivative 2, as promising tools for the development of new and more bioavailable derivatives useful in the treatment of breast cancer.     

中压主汽门阀盖螺栓断裂原因分析

中压主气门阀盖螺栓在运转两年后出现多根断裂,通过观察和分析20cr1Mo1VnbTiB高温螺栓断口的宏观及微观形貌,检验化学成分、测试力学性能,显微组织检验等方法,分析螺栓断裂原因。力学性能和化学成分符合要求,但螺纹根部粗糙度比较大,硬度为316 HBW2．5／187．5超过标准中规定的硬度252～302HBW上限值,金相组织是回火索氏体。分析结杲表明,螺纹根部粗糙,引起局部应力集中,全相组织不符合要求,硬度超过标准中的规定,晶粒粗大等是螺栓断裂的主要原因。在生产中,要加强高温紧固件性能检测,遵守拆装要求,定期喷涂防腐介质,以防此类事故发生。     

河津电厂1~#机中压主汽门跳闸阀异常的分析

长期以来河津电厂1#机组的凝结水温度偏高,在环境温度低,真空高的情况下,过冷度维持在-0.6~-1.0,通过查找,发现跳闸阀(RSV)在全开状态,实际位置与设计不符,使大量的高温高压蒸汽排入凝汽器,严重影响机组的安全经济运行。在本文中,介绍了中压主汽门跳闸阀工作原理,分析其异常的原因并提出解决的方法。     

呼吸道合胞病毒合胞体形成机制的研究进展

呼吸道合胞病毒(Respiratory syncytial virus,RSV)属于副黏病毒科肺炎病毒亚科病毒,是一种引起人严重呼吸道疾病的病原体,主要感染婴幼儿、老年人及免疫缺陷的成年人。病毒合胞体的形成是RSV感染细胞导致细胞病变的最主要特征。有研究表明,RSV的受体黏合和促融合活力主要依赖2个不同的刺突结构,分别是吸附(G)糖蛋白和融合(F)糖蛋白,G糖蛋白的主要作用是促进RSV与靶细胞的吸附,而F糖蛋白的主要作用是促进病毒与细胞、细胞与细胞之间的融合。本文就近几年RSV合胞体形成机制的研究进展作一综述。     

结核分枝杆菌TB10.4与呼吸道合胞病毒F1蛋白的融合表达

目的在大肠杆菌中融合表达结核分枝杆菌(Mycobacterium tuberculosis,MTB)TB10.4蛋白与呼吸道合胞病毒(Respiratory syncytial virus,RSV)F1蛋白。方法从MTB标准菌株H37Rv全基因组中扩增TB10.4(N/X)和TB10.4(N/B)基因,分别插入原核表达载体pET-28a和pET-30a中,构建重组表达质粒TB10.4(N/X)/pET-28a和TB10.4(N/B)/pET-30a;从F/18T/DH5α菌株中扩增F1(B/X)基因,与TB10.4(N/B)/pET-30a质粒连接,构建重组表达质粒TB10.4-F1/pET-30a;将质粒TB10.4(N/X)/pET-28a和TB10.4-F1/pET-30a分别转化感受态E.coliBL21(DE3),IPTG诱导表达;表达的重组蛋白进行Western blot鉴定。结果重组表达质粒TB10.4(N/X)/pET-28a和TB10.4-F1/pET-30a经双酶切及测序证明构建正确;表达的重组TB10.4和TB10.4-F1蛋白相对分子质量约为13 000和59 000,可与鼠抗His单抗特异性结合。结论成功在大肠杆菌中表达了重组融合蛋白TB10.4-F1,为进一步研究其免疫原性及保护性奠定了基础。     

侦察监视车及其光电传感器的发展现状

文中概述侦察监视车及其光电传感器的应用发展现状,重点介绍车载光电传感器系统 如车载激光测距机、可见光CCD /CMOS摄像机、非制冷红外热像仪,以及车载传感器桅杆、传感器稳定平台的发展概况。     

呼吸道合胞病毒空斑检测方法的建立及应用

目的建立呼吸道合胞病毒(RSV)空斑检测方法,并用于病毒滴度的定量。方法将不同稀释度的RSVA2株病毒液分别接种于Hep-2细胞单层,加0.6%营养琼脂糖覆盖,培养6d后用10%甲醛固定。去除覆盖层,0.05%中性红染色,按文献报道的方法进行空斑计数。建立空斑法测定RSV滴度的标准曲线,并验证空斑法的准确性及精密性,应用建立的空斑法检测RSV感染BALB/c小鼠肺组织中的RSV滴度。结果RSVA2株感染的Hep-2细胞出现典型的空斑,直径约1～3mm,形态呈圆形或类圆形。空斑法的最低检测限为3.4×101PFU/ml,线性关系良好,相关系数r=0.999996,准确性及精密性均良好。RSV感染的BALB/c小鼠肺组织标本均出现数量不等的空斑。结论所建立的RSV空斑测定方法敏感、准确,能稳定地对病毒滴度进行定量测定,为进一步研究RSV的感染性和免疫原性奠定了基础。     

Performance analysis of IP QoS provision model

The Performance of a heterogeneous IP QoS provision service model was analyzed. This model utilized RSVP technique to set up dynamic resource reservation interface between the user and the network, meanwhile, DiffServ technique was utilized to transmit class-based packets in different per hop behaviors. Furthermore, accordingly queue management and packets scheduling mechanisms were presented for end-to-end QoS guarantees and appropriate cooperation of network elements.     

Acute exacerbation of chronic obstructive pulmonary disease was associated with respiratory syncytial virus infection and the upregulation of TLR3

Respiratory syncytial virus (RSV) infection is known as a risk factor for chronic obstructive pulmonary disease (COPD). RSV infection induces the upregulation of Toll-like receptor 3 (TLR3). This study aimed to investigate the association of TLR3 with RSV induced acute exacerbations of chronic obstructive pulmonary disease (AECOPD). Serum/sputum samples from AECOPD patients, stable chronic obstructive pulmonary disease (SCOPD) patients, and healthy controls were collected. Nested PCR was used to detect RSV. The lung function parameters were assessed by blood gas and lung function analysis. The expression levels of inflammatory factors in sputum and serum samples were determined by enzyme-linked immunosorbent assay. BEAS-2B cell lines were infected with RSV, and the expression of TLR3 mRNA was determined by PCR and the levels of inflammatory factors were also investigated. The presence of RSV was detected in 3 SCOPD and 8 AECOPD patients, but not in healthy patients. The expression levels of TNF-α and IRF-3 in both sputum and serum samples of RSV-positive group were significantly higher than in RSV-negative group. TLR3 mRNA levels in RSV-positive group were significantly higher than those in RSV-negative group. Interestingly, the level of TLR3 mRNA expression was negatively correlated with oxygenation index and lung function parameters. Furthermore, BEAS-2B cells infected with RSV led to significant increase of the expression of TLR3 mRNA and inflammatory factors IFN-β, IL-13, IL-32, and TNF-α. Our observations indicate that AECOPD is associated with RSV infection and the upregulation of TLR3.