Effect of glutamine on preimplantation mouse embryo development in vitro

OBJECTIVES: The purpose of this research was to study the independent effect of the amino acid glutamine on preimplantation mouse embryo development in vitro. STUDY DESIGN: Two-cell stage mouse embryos were cultured in human tubal fluid medium in the presence and absence of 1 mmol/L of glutamine. Outcomes for morphology and cleavage rates were compared with Fisher's and Mann-Whitney's tests, respectively. RESULTS: Glutamine increased the proportion of embryos that developed to the blastocyst stage (86.4%) compared with those cultured without glutamine (59.1%) (P =.052). The percentages of embryos developing to the morula or hatching blastocyst stages were comparable in the 2 groups. Blastocyst total cell numbers were significantly higher in the glutamine group (34+/-1.7 vs 18.5+/-3.5, respectively; values are mean+/-SEM, P =.044). CONCLUSION: The amino acid glutamine independently improves preimplantation mouse embryo development in vitro. Further studies are needed to examine the applicability of these results to humans.     

传媒社会学顽野中的医患纠纷

探讨了医患纠纷是如何被纳入传媒的视野,并成为它关注的"焦点"。研究发现,媒体利益的二重性,新闻工作者的利益驱动,电视(或视频)的力量以及受众的力量是医患纠纷被纳入传媒视野的内在动力。换言之,医患纠纷成为传媒关注的"热点"是在把关人和受众的"合谋"下完成的。     

NF-κB translocation and endothelial cell activation is potentiated by macrophage-released signals co-secreted with TNF-α and IL-1β

Objective and Methods: Over-expression of the immune response can lead to pathological conditions such as septic shock or chronic inflammation. Endothelial cell activation by pro-inflammatory products of activated macrophages plays a key role in these conditions. Here we examine the response of primary human endothelial cells (HUVEC) to conditioned media (CM) obtained from LPS-activated macrophages. We further characterized the translocation of NF-B in the presence of CM by studying the degradation rate of individual IB isoforms.Results: We show that, as expected, CM induced NF-B translocation, as well as adhesion capacity in HUVEC. We further show that this response is critically dependent on TNF- and IL1 naturally present in the CM. However, both the amplitude of NF-B translocation and adhesiveness observed with CM were well beyond the saturation levels attained after the sole stimulation with recombinant TNF- and IL-1, either separately or together. Our results show that CM induced a faster degradation of the IB- and IB- isoforms than the recombinant cytokines, leading to an enhanced recruitment of NF-B activity.Conclusions: The above results suggest that the physiological context of factors co-secreted by LPS-activated macrophages enhances TNF- mediated endothelial activation.Received 5 October 2003; returned for revision 2 December 2003; accepted by A. Falus 19 May 2004     

构建叶酸修饰的乳腺癌靶向纳米超声造影微粒

BACKGROUND: Studies have testified that nano-ultrasound contrast agents have a strong permeability, making it possible to image the targeted tissues outside blood vessels and overcome the limitation that micron contrast agents are only available for the blood pool imaging. OBJECTIVE: To construct the folate-modified nanoparticles targeting breast cancer as ultrasound contrast agents, as well as to observe their ability to specifically bind to cells and imaging effect in vitro. METHODS: Both contrast agents, pegylated lactic acid-glycolic acid copolymer wrapping liquid fluorocarbon formed nanoparticles (mPP/PFOB) and folate modified pegylated lactic acid-glycolic acid wrapping liquid fluorocarbon formed nanoparticles (mPPF/PFOB), were constructed by phacoemulsification-evaporation method. (1)Biocompatibility detection: HFF-1 and MCF-7 cells in the logarithmic phase were cultivated with various concentrations (0, 0.005, 0.01, 0.02, 0.05, 0.1, 0.2 and 1 g/L) of mPP/PFOB or mPPF/PFOB for 24 hours respectively, and then the cell viability was measured. (2)Targeting ability detection in vitro: HFF-1 and MCF-7 cells in the logarithmic phase were divided into three groups. Cy5-labled mPP/PFOB and mPPF/PFOB were added into groups A and B, respectively; the cells in group C were pretreated with folate for 2 hours, and sequentially Cy5-labled mPPF/PFOB was added into group C. Fluorescence intensity was detected by flow cytometry after 0.5 hours of culture. The distribution of contrast agents in cells was observed using confocal microscopy after 20 minutes of culture. (3)Ultrasound imaging in vitro: there were three groups: saline was as group A; the suspension of saline and mPPF/PFOB nanoparticles was prepared as group B; MCF-7 cells were resuspended with the mixture of saline and mPPF/PFOB nanoparticles to prepare the suspension of nanoparticles and cells as group C. In each group, the suspension was added into latex gloves, that were then tightened and immersed in water. Finally, the ultrasound was use to detect the ultrasound imaging effect in vitro. RESULTS AND CONCLUSION: Neither nanoparticles were with significant cytotoxicity. The flow cytometry showed that the mean fluorescence intensity in MCF-7 cells of group B was significantly higher than that of groups A and C. But there were no significant differences in the mean fluorescence intensity in HFF-1 cells among the three groups. It was observed that mPPF/PFOB mainly gathered around the MCF-7 cell membrane, while mPP/PFOB randomly distributed in the cytoplasm. After mPPF/PFOB binding to MCF-7 cells, they could enhance ultrasound echo in vitro. These findings indicate that the targeted nanoparticles mPPF/PFOB have good biocompatibility and can specifically bind to breast cancer MCF-7 cells in vitro and enhance the imaging capability.     

Jade and the journalists: Media coverage of a young British celebrity dying of cancer

In contemporary western societies, dying usually occurs in old age, out of sight in hospitals and institutions; how then do lay people learn what dying is like? Since the 1970s, one source of information in Anglophone societies has come from individuals who have chosen to publicise their dying of cancer. This article examines the most high profile case of this to date in the UK; in 2009, celebrity Jade Goody publicised in tabloid newspapers and celebrity magazines the final weeks of her dying of cervical cancer. What did she and her media say and write about dying? This article examines the print coverage of her final weeks, and four different voices are identified: those of Goody, of journalists, of her publicist, and of photographers, each representing her dying somewhat differently. Two major themes are discussed: Jade’s struggles to retain autonomy (challenged by her disease and by other people), and the framing of her final weeks not primarily as a typical media cancer story of heroism, but as one of redemption in which she attained social respectability through dying.     

中国激光杂志社全媒体知识服务体系构建初探

目的 将传统媒体与新兴媒体相互融合、相互促进、共同发展,提出全媒体知识服务体系的构建概念,希望为其他科技类期刊开展全媒体知识服务提供一些借鉴。方法 从数字技术在出版领域的应用展开探讨,分析构建科技期刊全媒体知识服务体系的必要性。结果 提出以数字出版平台为核心,构建该服务体系的结构模型,介绍了中国激光杂志社在建立科技期刊全媒体知识服务体系过程中的实践经验,总结了其在探索中的创新与发展前景。结论 通过构建全媒体知识服务体系,向全媒体的转型是科技期刊数字化改革的一种较为稳妥并具有可操作性的思路。     

科技期刊跨媒体融合发展模式——以《建筑学报》为例

目的 在媒体融合的背景下科技期刊发展存在问题,需要探讨科技期刊的发展模式。方法 采取个案研究的方式,分析和总结科技期刊的发展策略。结果 科技期刊应该进行跨媒体融合,进行市场化的运作,明确科技期刊的市场定位,重视期刊的出版与经营,全面提升科技期刊的核心竞争力。结论 跨媒体融合发展是提升科技期刊竞争力的有效模式,也是未来科技期刊的发展趋势。