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Background Midkine (MK), a heparin-binding protein, participates in multiple cellular processes, such as immunity, cellular growth and apoptosis. Overwhelming evidence indicates that MK plays an important role in various pathological processes, including chronic inflammation, autoimmunity, cancer, and infection. Recent studies demonstrated that MK may be involved in the development of atherosclerosis, yet the mechanism has not been fully explored. Therefore, this study aims to investigate the effect and mechanism of MK on macrophage cholesterol efflux.Methods and Results:Using Oil Red O staining, NBD-cholesterol fluorescence labeling and enzymatic methods, it observed that MK markedly promoted macrophage lipid accumulation. Liquid scintillation counting (LSC) showed that MK decreased cholesterol efflux. Moreover, cell immunofluorescence, western blotting and quantitative real-time polymerase chain reaction (qRT-PCR) showed that MK downregulated ATP-binding membrane cassette transport protein A1 (ABCA1) expression. Functional promotion of ABCA1 expression attenuated the inhibitory effects of MK on cholesterol efflux, which reduced lipid accumulation. Additionally, intervention of adenosine monophosphate activated protein (AMPK)-mammalian target of rapamycin (mTOR) signaling molecule by the AMPK activator, AICAR, increased p-AMPK and ABCA1 expression, decreased p-mTOR expression and promoted cholesterol efflux, resulting in an obvious reduction in intracellular lipid content. Conclusions These data suggest that MK reduces the expression of ABCA1, inhibits the efflux of cholesterol and promotes the accumulation of lipids in RAW264.7 macrophages, and AMPK-mTOR signaling is involved in MK-mediated regulation of cholesterol metabolism in RAW264.7 macrophages.

Here, we present the complete genome sequence and annotation of

Based on a typical Expressway emergency case the 12.5 black powder explosion on Beijing-Zhuhai Expressway, this article built an expressway emergency inter-organizational communication network and then analyzed the communication barriers with Network Analysis Approach. The study finds that in hierarchical structures level, Expressway enterprise lack of communication with the local government; the subgroups that have business contact with Expressway enterprise in normal condition are difficult to share information in emergency with the subgroups that has no business relationship with expressway enterprise; the subgroups that have no business relationship with Expressway enterprise in normal condition are of great disparity in communication intensity internally and it is easy to cause over load for the core organization in communication; in the contrast, the subgroup that has business contact with expressway enterprise normally, the internal communication structure is more reasonable.

Four new types of Ir(III) complexes (ppy) 2 Ir(LX) (ppy = 2-phenylpyridine, LX = BTZ, 3-MeBTZ, 4-MeBTZ, and 4-TfmBTZ) were synthesized and investigated by optical spectroscopy, electrochemistry as well as density functional theory (DFT). These complexes all exhibit multi-emission bands under ultraviolet light excitation at room temperature because there are efficient energy transfers between different excited states ( 1 LC, 1 MLCT, 1 ILCT, 3 MLCT, 3 ILCT), especially for complexes I–III. The blue emitting relates to the fluorescence of Ir(R-BTZ) and the green emission originates in 3 MLCT emission of Ir(ppy) 2 fragment. The red emission corresponds to 3 ILCT transition (R-BTZ → ppy) for complexes I–III, but 3 MLCT transition of Ir(4-TfmBTZ) 2 fragment for (ppy) 2 Ir(4-TfmBTZ). The red emission peak wavelength can be fine-tuned from 583 to 626 nm by the electron withdrawing or donating substituent at 3- or 4-position of BTZ ligand. For these single component complexes with multicolor emitting, a very promising application is the generation of white light. Although these complexes span non-uniformly the spectral range of the visible region and consequently are insufficient to produce satisfactory white light characteristics, the luminescence mechanism of them provides a new strategy for designing organic white light-emitting material.

To observe the effect of electroacupuncture (EA) on changes of ultrastructure of oligodendrocytes in the marginal zone of the cerebral ischemia (CI) locus in rats with cerebral infarction so as to reveal its mechanism underlying improving ischemic cerebral diseases.Ninety male SD rats were randomized into sham operation, model and electroacupuncture (EA) groups which were further divided into five subgroups: 1 h, 1 d, 3 d, 7 d, and 21 d after CI (n = 6 in each subgroup). The CI model was established by occlusion of the middle cerebral artery. EA (1 - 3 mA) was applied to "Baihui" (GV 20) and "Dazhui" (GV 14) for 30 min, once a day for 1 h, 1 d, 3 d, 7 d and 21 d, respectively. The ultrastructural changes of oligodendrocytes in the marginal zone of the ischemic cerebral tissue were observed by transmission electron microscope. The immunoactivity levels of A2B5, O4 and 2',3'-cyclic-nucleotide 3'-phosphodiesterase (CNPase) for labeling the oligodendrocyte precursor cells, immature oligodendrocytes, and mature oligodendrocytes respectively were detected by immunohistochemistry.The oligodendrocytes were swelling in structure and increased in number after cerebral ischemia. Compared with the model group, the degree of swelling of oligodendrocytes was obviously decreased and new oligodendrocyte proliferation was found in the EA group. In comparison with the sham group, the immunoactivity levels of cerebral A2B5 and CNPase proteins on day 3 and 7 were significantly higher in the model group (P0. 05), while those of O4 on day 1, 3, 7 and 21 were obviously lower in the model group (P0. 01). Following EA intervention, the immunoactivity levels of cerebral A2B5, O4 and CNPase proteins were significantly up-regulated in the EA group in comparison with the model group (P0. 0 1 , P0. 05).EA intervention may reduce the structural damage of oligodendrocytes in CI rats, which may be associated with its effects in promoting the expression of cerebral A2B5, O4 and CNPase proteins, suggesting an involvement of glial cells in the protective effect of EA.

Atmospheric CO2 column concentration (column-averaged dry air mole fractions of atmospheric carbon dioxide) data obtained by ground-based hyperspectral observation is an important source of data for the verification and improvement of the results of CO2 retrieval based on satellite hyperspectral observation. However, few studies have been conducted on atmospheric CO2 column concentration retrieval based on ground-based spectral hyperspectral observation in China. In the present study, we carried out the ground-based hyperspectral observation in Xilingol Grassland, Inner Mongolia of China by using an observation system which is consisted of an optical spectral analyzer, a sun tracker, and some other elements. The atmospheric CO2 column concentration was retrieved using the observed hyperspectral data. The effect of a wavelength shift of the observation spectra and the meteorological parameters on the retrieval precision of the atmospheric CO2 concentration was evaluated and analyzed. The results show that the mean value of atmospheric CO2 concentration was 390.9 microg x mL(-1) in the study area during the observing period from July to September. The shift of wavelength in the range between -0.012 and 0.042 nm will generally lead to 1 microg x mL(-1) deviation in the CO2 retrievals. This study also revealed that the spectral transmittance was sensitive to meteorological parameters in the wavelength range of 6 357-6 358, 6 360-6 361, and 6 363-6 364 cm(-1). By comparing the CO2 retrievals derived from the meteorological parameters observed in synchronous and non-synchronous time, respectively, with the spectral observation, it was showed that the concentration deviation caused by using the non-synchronously observed meteorological parameters is ranged from 0.11 to 4 microg x mL(-1). These results can be used as references for the further improvement of retrieving CO2 column concentration based on spectral observation.

According to the strong interference in performance and the difficulty in register of the multi-color web offset press ,this paper uses the anti-interference ability of PLC and rich hardware and software resources of computer, adopting PLC and PC respectively as the on-site slave computer and host computer, at the same time, it uses camera as image acquisition tool. Based on all these above, the paper constructs a new type of register control system of multi-color web offset press. The paper also introduces the compositions of the hardware and software of this system in details. The experiment has improved that the automatic detection, image recognition and automatic calibration of the register marks can be realized by the joint control on image, PLC and configuration software, and it has a strong practical applicability

New heteroleptic iridium(III) complexes (ppz)2Ir(LX), which consist of two cyclometalated ligands ppz(1-phenylpyrazole) together with an ancillary ligand LX (LX= 2-(2'-hydroxylphenyl)benzothiazole (BTZ), 2-(3'-methyl-2'-hydroxylphenyl) benzothiazole (3-MeBTZ), 2-(4'-methyl-2'-hydroxylphenyl) benzothiazole (4-MeBTZ) and 2-(4'-Trifluoromethyl-2'hydroxylphenyl) benzothiazole (4-tfmBTZ)), were synthesized and characterized. The molecular structures and photophysical properties were characterized and analyzed comparatively. The results show that the four complexes have basically similar UV-Vis absorption spectra, fluorescence excitation and emission spectra. Their maximum emission peaks are located at 583-615 nm, and accompanied by a lower intensity emission band around 400 nm. The weak emissions around 400 nm are ascribed to the radi ation transition of single state excition from ancillary ligand BTZ perturbed by metallic ion, and light emission around long-wave-length to the radiation transition of 3MLCT of Ir(BTZ) fragment. While the triplet state 3 MLCT of Ir(ppz)2 fragment might be quenched at room temperature. For all complexes, the excitations with maximum efficiency are located at 250-310 nm, which indicates that main contributor to light emitting is ligand-centered absorption (1pi-pi*) of ppz and BTZ rather than 3MLCT transitions, and thus provides a striking evidence that there is intersystem crossing from 1pi-pi* state to 3MLCT state in these complexes. Compared with Ir(ppz)3, these complexes not only have stronger phosphorescence at room temperature but also their emission color can be tuned by modifying ancillary ligand.

The implantation of intravascular stents has become a new method to cure stenosis in arteries with its low injury and high efficiency. The mechanical behavior of the stents is studied by the finite element method. The compression behavior is simulated with stent models of different sizes and geometry structures whose material is cobalt-chromium alloy. Experiments are also carried out to verify the simulation method, which shows that the finite element model can substitute the stent to some extent in which its mechanical behavior is studied. The results show that the reaction stress of the stent increases with the thickness of the strut. Besides, the smaller metal surface area ratio will result in a smaller elongation ratio. All these are helpful and instructive to the proper designs and actual operation of intravascular stents.

To obtain the recombinant protein of an antigen gene Ts88 of Trichinella spiralis and identify the characteristics of the recombinant protein.Ts88 cDNA obtained by immunoscreening the cDNA library of adult T. spiralis was subcloned into the pET-28c(+) expression vector and expressed in E. coli. Mice were immunized with the fusion protein incorporated into Freund' s adjuvant and the immune sera were collected. The titers of the Ts88 immune sera and the antigenicity of the recombinant protein were detected by ELISA and Western blotting. Immuno-fluorescence test was performed in order to confirm the distribution of Ts88 protein in the worm.The fragment of Ts88 gene was expressed successfully in E. coli and a highly purified fusion protein was obtained. Immunization with the recombinant protein in mice produced high titers of antibodies, which recognized some components of native antigens of soluble proteins from adult worm of T. spiralis. Western blotting analysis showed that Ts88 recombinant antigen was recognized by all the positive sera, such as the sera from infected or immunized rabbits, from infected swine and from patients of trichinosis. Immuno-fluorescence test confirmed that Ts88 protein mainly distributed in the cuticle surface of the worm.The Ts88 antigen gene from T. spiralis was successfully expressed. The recombinant protein presented antigenicity.

Iridium (III) complexes with 2-phenylpyridine (ppy) have been demonstrated as a type of promising phosphorescence dopant in emitting layers of organic light emitting diodes (OLEDs). In most iridium (III) complexes, there exist the strong spin-orbit coupling between π-orbitals of cyclometalated ligands and 5d orbitals of the centric iridium. We study a novel iridium (III) complex (ppy)2Ir(4-TfmBTZ) with ppy as cyclometalated ligands and 2-(4-trifluoromethyl-2-hydroxylphenyl)benzothiazole (4-TfmBTZ) as an ancillary ligand using the Gaussian 03 program. The geometries, electronic structures and spectroscopic properties of this iridium (III) complex are investigated by density functional theory (DFT) and time-dependent density functional theory (TD-DFT). The results show that the spin-orbit coupling occurs not only between ppy and iridium atom but also between 4-TfmBTZ and iridium atom in this complex. The highest occupied molecular orbital is dominantly localized on the Ir atom and 4-TfmBTZ ligand, while the lowest unoccupied molecular orbital on 4-TfmBTZ ligand. The triplet lowest-lying transition is attributed to the Ir-to-4-TfmBTZ charge-transfer (3MLCT) transition while the sub-low-lying transitions are assigned to the 3MLCT transitions of Ir(ppy)2. The nature of the lowest unoccupied orbital changes from ppy-localized to 4-TfmBTZ-localized and reveals that phosphorescent color of Ir(III) complex can be controlled by the ancillary ligand and substituent.