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201.
Eunice Sok Ping Leong Yan Jun Liu Chan Choy Chum Jing Hua Teng 《Plasmonics (Norwell, Mass.)》2013,8(2):1221-1226
Optical magnetic responses were demonstrated in subwavelength Ag–MgF2–Ag grating structures for transverse magnetic-polarized light. The subwavelength Ag–MgF2–Ag grating structures were fabricated using e-beam lithography followed by a lift-off process. By fixing the Ag–MgF2–Ag strip dimension, the effect of the stripe width on the magnetic resonances was compared for two different grating pitches. With further reduced grating pitch, we pushed the optical magnetic resonances to near UV (deep blue). Numerical simulations confirmed our experimental observations and were in good agreement with the experimental results. 相似文献
202.
Tianjiao Lyu Nan Jia Jieyu Wang Xiaohui Yan Yinhua Yu Zhen Lu Robert C Bast Jr Keqin Hua Weiwei Feng 《Epigenetics》2013,8(12):1330-1346
The initiation of angiogenesis can mark the transition from tumor dormancy to active growth and recurrence. Mechanisms that regulate recurrence in human cancers are poorly understood, in part because of the absence of relevant models. The induction of ARHI (DIRAS3) induces dormancy and autophagy in human ovarian cancer xenografts but produces autophagic cell death in culture. The addition of VEGF to cultures maintains the viability of dormant autophagic cancer cells, thereby permitting active growth when ARHI is downregulated, which mimics the “recurrence” of growth in xenografts. Two inducible ovarian cancer cell lines, SKOv3-ARHI and Hey-ARHI, were used. The expression level of angiogenesis factors was evaluated by real-time PCR, immunohistochemistry, immunocytochemistry and western blot; their epigenetic regulation was measured by bisulfite sequencing and chromatin immunoprecipitation. Six of the 15 angiogenesis factors were upregulated in dormant cancer cells (tissue inhibitor of metalloproteinases-3, TIMP3; thrombospondin-1, TSP1; angiopoietin-1; angiopoietin-2; angiopoietin-4; E-cadherin, CDH1). We found that TIMP3 and CDH1 expression was regulated epigenetically and was related inversely to the DNA methylation of their promoters in cell cultures and in xenografts. Increased H3K9 acetylation was associated with higher TIMP3 expression in dormant SKOv3-ARHI cells, while decreased H3K27me3 resulted in the upregulation of TIMP3 in dormant Hey-ARHI cells. Elevated CDH1 expression during dormancy was associated with an increase in both H3K4me3 and H3K9Ac in two cell lines. CpG demethylating agents and/or histone deacetylase inhibitors inhibited the re-growth of dormant cancer cells, which was associated with the re-expression of anti-angiogenic genes. The expression of the anti-angiogenic genes TIMP3 and CDH1 is elevated during dormancy and is reduced during the transition to active growth by changes in DNA methylation and histone modification. 相似文献
203.
Hai Chun Liu Hua Zhao Jian Chen Wen Liang Wu Hong Liang Wang Gang Jun Jiao Yun Zhen Chen 《Journal of molecular histology》2013,44(5):535-544
Decreased levels of serum insulin-like growth factor-1 (IGF-1) have been proven to cause osteoporosis. Gene transfer of IGF-1 offers an attractive technology to treat skeletal metabolic disorders including osteoporosis, but the viral vectors are limited by their high antigenicity and immune response. Our purpose was to investigate the expression of a non-invasive vector, recombinant plasmid enhanced green fluorescent protein-N1 (pEGFP-N1) that transferred IGF-1 gene into ovariectomized (OVX) rats in vivo and evaluate the effect of this therapy on osteoporosis. OVX or sham operations were performed in 60 female, 7-month-old unmated SD rats. 12 weeks after OVX operation, the vectors were transfected to the 10-month-old rats and experimental data were detected from 48 h to 7 week after transfection. Our results showed that remarkable expression of fluorescence and serum IGF-1 was observed in the rats transfected by recombinant plasmids, indicating that IGF-1 gene was successfully transferred to OVX rats by injecting the vector through hydrodynamic method via the tail vein. The bone metabolism index including serum alkaline phosphatase, the histomorphometric parameters of lumbar vertebra including trabecular area percentage, trabecular thickness, trabecular number and trabecular separation, and the bone mineral density (BMD) and biomechanical parameters of lumbar vertebra including BMD, maximum condensing force, crushing strength in OVX rats transfected by pEGFP-N1-IGF-1 were improved remarkably compared with OVX+pEGFP-N1 rats, indicating that the transfection of recombinant plasmid pEGFP-N1-IGF-1 played a significant role in alleviating osteoporosis in rats induced by OVX. This encouraged a potential approach of IGF-1 gene therapy to the treatment of osteoporosis. 相似文献
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Jian-Hua Zhang Xiao-Di Peng Hua Liu Jörg Raisch Ru-Bin Wang 《Cognitive neurodynamics》2013,7(6):477-494
The human operator’s ability to perform their tasks can fluctuate over time. Because the cognitive demands of the task can also vary it is possible that the capabilities of the operator are not sufficient to satisfy the job demands. This can lead to serious errors when the operator is overwhelmed by the task demands. Psychophysiological measures, such as heart rate and brain activity, can be used to monitor operator cognitive workload. In this paper, the most influential psychophysiological measures are extracted to characterize Operator Functional State (OFS) in automated tasks under a complex form of human–automation interaction. The fuzzy c-mean (FCM) algorithm is used and tested for its OFS classification performance. The results obtained have shown the feasibility and effectiveness of the FCM algorithm as well as the utility of the selected input features for OFS classification. Besides being able to cope with nonlinearity and fuzzy uncertainty in the psychophysiological data it can provide information about the relative importance of the input features as well as the confidence estimate of the classification results. The OFS pattern classification method developed can be incorporated into an adaptive aiding system in order to enhance the overall performance of a large class of safety–critical human–machine cooperative systems. 相似文献
208.
Guoxu Ma Haifeng Wu Jingquan Yuan Lizhen Wu Qingxia Zheng Zhaocui Sun Xiaoru Fan Hua Wei Junshan Yang Xudong Xu 《Phytochemistry letters》2013,6(1):152-155
Five phenylpropanoids including one new compound balanophonin A (1), one new natural compound balanophonin B (2) were isolated from the seeds of Lithocarpus pachylepis for the first time. Their structures were elucidated by various spectroscopic techniques (UV, IR, MS, CD, 1D and 2D NMR). All compounds were evaluated for their anti-inflammatory activities on lipopolysaccharide (LPS)-induced nitric oxide (NO) production in RAW 264.7. 相似文献
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