AEG-1 is associated with hypoxia-induced hepatocellular carcinoma chemoresistance via regulating PI3K/AKT/HIF-1alpha/MDR-1 pathway

Hypoxia is a common characteristic of hepatocellular carcinoma (HCC) associated with reduced response to chemotherapy, thus increasing the probability of tumor recurrence. Astrocyte elevated gene-1 (AEG-1) has been involved in a wide array of cancer progression including proliferation, chemoresistance, angiogenesis and metas- tasis, but its effect on HCC chemoresistance induced by hypoxia is unclear. In this study, expression of AEG-1 and multiple drug resistance (MDR-1) were examined in HCC using immunohistochemical staining and RT- PCR. Furthermore, their expression levels were detected in HCC HepG2 cells in normoxia or hypoxia via RT- PCR and Western blot assays. Specific shRNAs were used to silence AEG-1 expression in HepG2 cells. Results showed AEG-1 and MDR-1 expression were higher in HCC tissues than in adjacent normal tissues. Incubation of HepG2 cells in hypoxia increased expression of AEG-1 and MDR-1, compared to incubation in normoxia. Exposure to hypoxia blunted sensitivity of HepG2 cells to Adriamycin, 5-fluorouracil and cis-platinum, as evi- denced by modest alterations in cell viability and apoptosis rate, however the sensitivity was elevated with AEG- 1 knockdown. PI3K/AKT/HIF-1/MDR-1 pathway was attenuated following AEG-1 knockdown in hypoxia. Based on these data, it was suggested that AEG-1 is associated with hypoxia-induced hepatocellular carcinoma chemoresistance via regulating PI3K/AKT/HIF-1/MDR-1 pathway. This study uncovered a novel potential tar- get for development of an effective therapy against hypoxia-induced HCC chemoresistance

Surface Plasmon Enhanced Chemical Reactions on Metal Nanostructures

Noble metal nanomaterials as plasmonic photocatalysts can strongly absorb visible light and generate localized surface plasmon resonance (SPR), which in turn depends on the size, shape, and surrounding of the plasmonic metal nanomaterials (PMNMs). Remarkably, the high-efficiency conversion of solar energy into chemical energy was expected to be achieved by PMNMs. Therefore, researchers have chosen PMNMs to improve the photocatalytic activity toward targeted molecules. This enhancement can be achieved by the effective separation of photogenerated electrons and holes of the PMNMs in the presence of light. Surface-enhanced Raman spectroscopy (SERS) has been performed for obtaining information about the photochemically transformed surface species at molecular levels. A profound understanding of kinetic mechanisms is needed for the development of novel plasmonic catalysts toward various chemical transformations of targeted molecules. In this chapter, based on the above discussions, the participation of SPR excitation in PMNMs and photocatalysis toward chemical transformations of SERS-active organic molecules such as aromatic amino and nitro compounds based on PMNMs have been discussed in detail through theoretical and experimental studies. Eventually, a summary and the future directions of this study are discussed

From Additional Symmetries to Linearization of Virasoro Symmetries

We construct the additional symmetries and derive the Adler-Shiota-van Moerbeke formula for the two-component BKP hierarchy. We also show that the Drinfeld-Sokolov hierarchies of type D, which are reduced from the two-component BKP hierarchy, possess symmetries written as the action of a series of linear Virasoro operators on the tau function. It results in that the Drinfeld-Sokolov hierarchies of type D coincide with Dubrovin and Zhang's hierarchies associated to the Frobenius manifolds for Coxeter groups of type D, and that every solution of such a hierarchy together with the string equation is annihilated by certain combinations of the Virasoro operators and the time derivations of the hierarchy.Comment: 22 page

Digital Quantum Simulation of Yang-Mills Theory and Hadronization

A quantum algorithm with polynomial complexity to non-perturbatively calculate the Dyson series of SU(N) Yang-Mills theory is formulated in terms of quantum circuits. Applying it to the quantum simulation of quantum chromodynamics (QCD), the quark and gluon's wave functions evolved from the initial states by the interactions can be observed and the information from wave functions can be extracted at any discrete time. This may help us understand the natures of the hadronization which has been an outstanding question of significant implication on high energy phenomenological studies.Comment: 8 pages, 1 figur

Infection of Ophiocordyceps sinensis fungus causes dramatic changes in the microbiota of its Thitarodes host

The Chinese cordyceps is a unique and valuable parasitic complex of Thitarodes/Hepialus ghost moths and the Ophiocordyceps sinensis fungus for medicine and health foods from the Tibetan Plateau. During artificial cultivation of Chinese cordyceps, the induction of blastospores into hyphae is a prerequisite for mummification of the infected Thitarodes larvae. To explore the microbial involvement in the induction of mycelia-blastospore transition, the microbiota of the hemolymph and gut from Thitarodes xiaojinensis larvae with or without injected O. sinensis blastospores were investigated by culture-dependent and -independent methods. Twenty-five culturable bacterial species and 14 fungal species, together with 537 bacterial operational taxonomic units (OTUs) and 218 fungal OTUs, were identified from the hemolymph and gut of samples from five stages including living larvae without injected fungi (A) or with high blastospore load (B), mummifying larvae without mycelia coating (C), freshly mummifying larvae coated with mycelia (D), and completely mummified larvae with mycelia (E). Two culturable bacterial species (Serratia plymuthica, Serratia proteamaculans), and 47 bacterial and 15 fungal OTUs were considered as shared species. The uninfected larval hemolymph contained 13 culturable bacterial species but no fungal species, together with 164 bacterial and 73 fungal OTUs. To our knowledge, this is the first study to detect large bacterial communities from the hemolymph of healthy insect larvae. When the living larvae contained high blastospore load, the culturable bacterial community was sharply inhibited in the hemolymph but the bacterial and fungal community greatly increased in the gut. In general, high blastospore load increased bacterial diversity but sharply decreased fungal diversity in the hemolymph and gut by OTUs. The bacterial loads of four culturable species (Chryseobacterium sp., Pseudomonas fragi, S. plymuthica, S. proteamaculans) increased significantly and O. sinensis and Pseudomonas spp. became dominant microbes, when the infected larvae became mummified, indicating their possible involvement in the larval mummification process. The discovery of many opportunistic pathogenic bacteria in the hemolymph of the healthy larvae, the larval microbial diversity influenced by O. sinensis challenge and the involvement of dominant bacteria during larval mummification process provide new insight into the infection and mummification mechanisms of O. sinensis in its Thitarodes hosts

A Study on SSVEP-Based BCI

Abstract⎯Brain-computer interface (BCI) can help the deformity person finish some basic activities. In this paper, we concern some critical aspects of SSVEP based BCI, including stimulator selection, method of SSVEP extracting in a short time, stimulating frequency selection, and signal electrode selection. The conclusion is that the stimulator type should be based on the complexity of the BCI system, the method based on wavelet analysis is more valid than the power spectrum method in extracting the SSVEP in a short period, and the selections of stimulating frequency and electrode are important in designing a BCI system. These contents are meaningful for implementing a real SSVEP-based BCI. Index Terms⎯Brain-computer interface, electroencephalogram, steady-state visual evoked potential

Manipulating Synchronous Optical Signals with a Double Λ\Lambda Atomic Ensemble

We analyze a double $\Lambda$ atomic configuration interacting with two signal beams and two control beams. Because of the quantum interference between the two $\Lambda$ channels, the four fields are phase-matched in electromagnetically induced transparency. Our numerical simulation shows that this system is able to manipulate synchronous optical signals, such as generation of optical twin signals, data correction, signal transfer and amplification in the atomic storage.Comment: 5 pages, 7 figure

From plasmon-enhanced molecular spectroscopy to plasmon-mediated chemical reaction

该论文在田中群教授指导下完成，第一作者为iChEM中心2013级博士生战超。 表面等离激元效应可以在时间和空间上实现光子、电子和热能的重新分配。表面等离激元增强分子光谱由于其具有超高的灵敏度在过去四十年里引起了人们的广泛关注并得到快速发展。近年，表面等离激元效应介导的化学反应得到广泛的关注。该综述系统介绍了表面等离激元效应、表面等离激元增强分子光谱和表面等离激元介导化学反应的背景和基础理论，并与传统热化学、光化学和光催化进行对比。通过将表面等离激元介导化学反应与表面等离激元增强分子光谱以及其它反应类型进行比较，归纳出表面等离激元介导化学反应的独特科学内涵，展示了较完整的表面等离激元介导化学反应的物理化学图像。系统深入地分析了表面等离激元介导化学反应的特色和优势、影响因素及其之间的关联性，进而讨论高效利用表面等离激元来介导化学反应的策略，并对该领域做了展望。【Abstract】The excitation of surface plasmons (SPs), collective oscillation of conduction electrons in nanostructures, can redistribute photon, electron and heat energy in time and space. Making use of this ability, plasmon-enhanced molecular spectroscopies (PEMS) with ultra-high sensitivity and surface selectivity have attracted much attention and developed significantly in the past four decades. Recently, SPs have impacted the discipline of chemistry, through plasmon-mediated chemical reactions (PMCR). PMCR exhibit some obvious differences from, and potential advantages over traditional thermal-chemistry, photo-chemistry and photo-catalysis. Our physicochemical understanding of PMCR is still far from complete. In this review, we analyze the common ground and distinctive features of PEMS and PMCR; comparing as well, PMCR and traditional photo-chemical and thermal-chemical reactions. We then discuss how to advance PMCR by rationally designing and fabricating plasmonic nanostructures, selecting suitable surface/interface mediators and teaming them synergistically.We are deeply grateful to M. Moskovits for his very helpful suggestions and careful academic and English editing throughout the manuscript. This work is financially supported by the National Natural Science Foundation of China (21533006, 21621091, 91427304 and 21403180) and the Ministry of Science and Technology of China (2015CB932300). 研究工作得到国家自然科学基金委(21533006、21621091、91427304）和科技部重大科学研究计划（2015CB932300）的支持