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Transient global cerebral ischemia (tGCI) causes excessive release of glutamate from neurons. Astrocytic glutamate transporter-1 (GLT-1) and glutamine synthetase (GS) together play a predominant role in maintaining glutamate at normal extracellular concentrations. Though our previous studies reported the alleviation of tGCI-induced neuronal death by hypoxic preconditioning (HPC) in hippocampal CA1 of adult rats, the underlying mechanism has not yet been fully elaborated. In this study, we aimed to investigate the roles of GLT-l and GS in the neuroprotection mediated by HPC against tGCI and to ascertain whether these roles can be regulated by connexin 43 (Cx43) and c-Src activity. We found that HPC decreased the level of extracellular glutamate in CA1 after tGCI via maintenance of GLT-1 expression and GS activity. Inhibition of GLT-1 expression with dihydrokainate (DHK) or inhibition of GS activity with methionine sulfoximine (MSO) abolished the neuroprotection induced by HPC. Also, HPC markedly upregulated Cx43 and inhibited p-c-Src expression in CA1 after tGCI, whereas inhibition of Cx43 with Gap26 dramatically reversed this effect. Furthermore, inhibition of p-c-Src with 4-amino-5-(4-chlorophenyl)-7-(t-butyl) pyrazolo (3, 4-d) pyrimidine (PP2) decreased c-Src activity, increased protein levels of GLT-1 and Cx43, enhanced GS activity, and thus reduced extracellular glutamate level in CA1 after tGCI. Collectively, our data demonstrated that reduced extracellular glutamate induced by HPC against tGCI through preventing the reduction of GLT-1 expression and maintaining GS activity in hippocampal CA1, which was mediated by upregulating Cx43 expression and inhibiting c-Src activity.

Total flavonoids isolated from Radix Tetrastigmae (RTFs) possess immunomodulatory activity, particularly on inflammation. In mice with lipopolysaccharide (LPS)-induced acute lung injury (ALI), treatment with RTFs at 40, 80 and 160 mg/kg significantly reduced leukocyte infiltration, improved histopathological changes in lung tissues and decreased the LPS-induced production of several inflammatory mediators in the bronchoalveolar lavage fluid (BALF), which included the chemotatic factors, granulocyte colony-stimulating factor, monocyte inflammatory protein-1α and B-lymphocyte colony inflammatory cytokines, including interleukin (IL)-1β, IL-6, IL-12p40 and tumor necrosis factor-α, in a dose-dependent manner. In addition, the expression of the Toll-like receptor 4 (TLR4)/myeloid differentiation factor-2 (MD-2) compound, the phosphorylation of p38 mitogen-activated protein kinase (p38MAPK), c-Jun N-terminal kinase (JNK) and nuclear transcription factor-ΚB (NF-ΚB), in addition to the DNA binding activity of NF-ΚB p65 in lung tissues, were all attenuated following RTF treatment. However, RTF treatment had no effect on extracellular signal-regulated kinase (ERK). In conclusion, RTFs contributed to the regulation of LPS-induced ALI through the TLR4/MD-2-mediated NF-ΚB, JNK and p38MAPK pathways. This may be a potential therapeutic option for the treatment of inflammatory diseases. [ABSTRACT FROM AUTHOR]

This study investigated the effect of transplantation of bone marrow mesenchymal stem cells (BM-MSCs) on functional deterioration and neuroinflammatory response in aged C57BL/6J mice. Mice were divided into 3 groups: normal aged group, saline control group, and BM-MSCs treatment group. Saline and BM-MSCs were administrated by intraventricular injection into the right ventricle. Spatial Y-maze (SYM) test, novel objective recognition (NOR) test, and locomotor activity test were used to evaluate cognitive and locomotor ability at 7 and 42 days after transplantation. Microglia and astrocyte expression in the hippocampus CA1 region and dentate gyrus (DG) were evaluated by immunohistochemical method. Furthermore, the content of TNF-α, IL-1α, and IL-1β in the hippocampus and cortex were detected with ELISA. We found that BM-MSCs transplantation increased time in novel arm and percentage of alteration in SYM test, discrimination ratio and discrimination index in the NOR test, and traveled total distance and mean velocity in the locomotor activity test. It also inhibited microglia and astrocyte expression, and reduced the content of IL-1α and IL-1β in the hippocampus. Our results suggested that BM-MSCs transplantation could delay cognitive and locomotor function deterioration through inhibiting neuroinflammation response, which would provide a rationale for exploring the viability of using BMMSCs transplantation in cognitive deficit diseases. [ABSTRACT FROM AUTHOR]

Understanding circuit function requires the characterization of component neurons and their neurotransmitters. Previous work on radula protraction in the Aplysia feeding circuit demonstrated that critical neurons initiate feeding via cholinergic excitation. In contrast, it is less clear how retraction is mediated at the interneuronal level. In particular, glutamate involvement was suggested, but was not directly confirmed. Here we study a suspected glutamatergic retraction interneuron, B64. We used the representational difference analysis (RDA) method to successfully clone an Aplysia vesicular glutamate transporter (ApVGLUT) from B64 and from a glutamatergic motor neuron B38. Previously, RDA was used to characterize novel neuropeptides. Here we demonstrate its utility for characterizing other types of molecules. Bioinformatics suggests that ApVGLUT is more closely related to mammalian VGLUTs than to Drosophila and Caenorhabditis elegans VGLUTs. We expressed ApVGLUT in a cell line, and demonstrated that it indeed transports glutamate in an ATP and proton gradient-dependent manner. We mapped the ApVGLUT distribution in the CNS using in situ hybridization and immunocytochemistry. Further, we demonstrated that B64 is ApVGLUT positive, supporting the idea that it is glutamatergic. Although glutamate is primarily an excitatory transmitter in the mammalian CNS, B64 elicits inhibitory PSPs in protraction neurons to terminate protraction and excitatory PSPs in retraction neurons to maintain retraction. Pharmacological data indicated that both types of PSPs are mediated by glutamate. Thus, glutamate mediates the dual function of B64 in Aplysia. More generally, our systematic approaches based on RDA may facilitate analyses of transmitter actions in small circuits with identifiable neurons. [ABSTRACT FROM AUTHOR]

Anthocyanin and proanthocyanidin (PA) are important secondary metabolites and beneficial to human health. Their biosynthesis is induced by jasmonate (JA) treatment and regulated by MYB transcription factors (TFs). However, which and how MYB TFs regulate this process is largely unknown in apple. In this study, MdMYB9 and MdMYB11 which were induced by methyl jasmonate (MeJA) were functionally characterized. Overexpression of MdMYB9 or MdMYB11 promoted not only anthocyanin but also PA accumulation in apple calluses, and the accumulation was further enhanced by MeJA. Subsequently, yeast two-hybrid, pull-down and bimolecular fluorescence complementation assays showed that both MYB proteins interact with MdbHLH3. Moreover, Jasmonate ZIM-domain (MdJAZ) proteins interact with MdbHLH3. Furthermore, chromatin immunoprecipitation- quantitative PCR and yeast one-hybrid assays demonstrated that both MdMYB9 and MdMYB11 bind to the promoters of ANS, ANR and LAR, whereas MdbHLH3 is recruited to the promoters of MdMYB9 and MdMYB11 and regulates their transcription. In addition, transient expression assays indicated that overexpression of MdJAZ2 inhibits the recruitment of MdbHLH3 to the promoters of MdMYB9 and MdMYB11. Our findings provide new insight into the mechanism of how MeJA regulates anthocyanin and PA accumulation in apple. [ABSTRACT FROM AUTHOR]

Two new water-soluble copper(II)-dipeptide complexes: [Cu(glygly)(PyTA)]ClO4·1.5H2O (1) and [Cu(glygly)-(PzTA)]ClO4·1.5H2O (2) (glygly = glycylglycine anion, PyTA = 2,4-diamino-6-(2'-pyridyl)-1,3,5-triazine and PzTA = 2,4-diamino-6-(2'-pyrazino)-1,3,5-triazine), utilizing two interrelated DNA base-like ligands (PyTA and PzTA), have been synthesized and characterized. The structure elucidation for 1 performed by single crystal X-ray diffraction showed a one dimensional chain conformation in which the central copper ions arrange in a five-coordinate distorted square-pyramidal geometry. Spectroscopic titration, viscosity and electrophoresis measurements revealed that the complexes bound to DNA via an outside groove binding mode, and cleaved pBR322 DNA efficiently in the presence of ascorbate, probably via an oxidative mechanism with the involvement of *OH and *O2-. Notably, the complexes exhibited considerable in vitro cytotoxicity against four human carcinoma cell lines (HepG2, HeLa, A549 and U87) with IC50 values ranging from 41.68 to 159.17 µM, in addition to their excellent SOD mimics (IC50 ~ 0.091 and 0.114 µM). Besides, multispectroscopic evidence suggested their HSA-binding at the cavity containing Trp-214 in subdomain IIA with moderate affinity, mainly via hydrophobic interaction. Further, the molecular docking technique utilized for ascertaining the mechanism and mode of action towards DNA and HSA theoretically verified the experimental results. [ABSTRACT FROM AUTHOR]

SiO2 films were deposited on single-crystalline silicon substrates by ion beam sputtering technology. Optical constants of SiO2 films are calculated from spectroscopic ellipsometry data, transmittance spectra and reflectance spectra by WVASE32 software, and the best fitted method is obtained for calculating optical constants of dielectric materials in the ultraviolet-visible-infrared (UV-VIS-IR) range. In the UV-VIS-NIR spectral range, refractive indices of SiO2 films are calculated separately by both ellipsometry data and reflectance spectra, and the obtained results are almost the same. Complex dielectric functions of SiO2 films in the IR spectral range are accurately calculated with infrared transmission spectra using the GenOsc model. The obtained accuracy complex refractive index of SiO2 films in the wavelength region from 0.19 μm to 25 μm is of great importance for the design of high quality coatings, such as ultra-low loss coating. [ABSTRACT FROM AUTHOR]

Childhood emotional trauma contributes significantly to certain psychopathologies, such as post-traumatic stress disorder. In experimental animals, however, whether or not early-life stress results in behavioral abnormalities in adult animals still remains controversial. Here, we investigated both short-term and long-term changes of anxiety- and depression-like behaviors of Wistar rats after being exposed to chronic feral cat stress in juvenile ages. The 2-week predator stress decreased spontaneous activities immediately following stress but did not increase depression- or anxiety-like behaviors 4 weeks after the stimulation in adulthood. Instead, juvenile predator stress had some protective effects, though not very obvious, in adulthood. We also exposed genetic depression model rats, Wistar Kyoto (WKY) rats, to the same predator stress. In WKY rats, the same early-life predator stress did not enhance anxiety- or depression-like behaviors in both the short-term and long-term. However, the stressed WKY rats showed slightly reduced depression-like behaviors in adulthood. These results indicate that in both normal Wistar rats and WKY rats, early-life predator stress led to protective, rather than negative, effects in adulthood. [ABSTRACT FROM AUTHOR]

By using first-principles simulations based on time-dependent density functional theory, the chemical reaction of an HCl molecule encapsulated in C60 induced by femtosecond laser pulses is observed. The H atom starts to leave the Cl atom and is reflected by the C60 wall. The coherent nuclear dynamic behaviors of bond breakage and recombination of the HCl molecule occurring in both polarized parallel and perpendicular to the H—Cl bond axis are investigated. The radial oscillation is also found in the two polarization directions of the laser pulse. The relaxation time of the H—Cl bond lengths in transverse polarization is slow in comparison with that in longitudinal polarization. Those results are important for studying the dynamics of the chemical bond at an atomic level. [ABSTRACT FROM AUTHOR]

The space environment monitor (SEM), onboard the Chinese meteorological satellites FengYun-3A/B, has the abilities to measure proton flux in 3-300-MeV energy range and electron flux in 0.15-5.7-MeV energy range. SEM can also detect the heavy ion compositions, satellite surface potential, the radiation dose in sensors, and the single events. The space environment information derived from SEM can be utilized for satellite security designs, scientific studies, development of radiation belt models, and space weather monitoring and disaster warning. In this paper, the SEM's instrument characteristics are introduced, and the postlaunch calibration algorithm is presented. The applications in monitoring space weather events and the service for manned spaceflights are also demonstrated. [ABSTRACT FROM AUTHOR]

A novel method of combining sol--gel and hydrothermalassisted processes was developed to synthesize poly(ethyleneimine)- functionalized silica-supported organicinorganic hybrid sorbents with high adsorption capacity. Fourier transform infrared spectroscopy and nitrogen gas sorption were utilized to characterize the hybrid sorbents. Poly(ethyleneimine)-functionalized hybrid sorbents had high static adsorption capacity of 91.5 mg g-1 for Pb(II) ions, displayed stable adsorption in the range of pH 4--8, offered a fast rate, and reached an equilibrium within 20min. [ABSTRACT FROM AUTHOR]

In this paper, the normal derivative of the radial basis function (RBF) is introduced into the reproducing kernel particle method (RKPM), and the improved reproducing kernel particle method (IRKPM) is proposed. The method can decrease the errors on the boundary and improve the accuracy and stability of the algorithm. The proposed method is applied to the numerical simulation of piezoelectric materials and the corresponding governing equations are derived. The numerical results show that the IRKPM is more stable and accurate than the RKPM. [ABSTRACT FROM AUTHOR]

Since knowledge of the structure and elastic properties of Ta at high pressures is critical for addressing the recent controversies regarding the high-pressure stable phase and elastic properties, we perform a systematical study on the high-pressure structure and elastic properties of the cubic Ta by using the first-principles method. Results show that the initial body-centered cubic phase of Ta remains stable even up to 500 GPa and the high-pressure elastic properties are excellently consistent with the available experimental results. Besides, the high-pressure sound velocities of the single- and poly-crystals Ta are also calculated based on the elastic constants, and the predications exhibit good agreement with the existing experimental data. [ABSTRACT FROM AUTHOR]

A better understanding of neuromodulation in a behavioral system requires identification of active modulatory transmitters. Here, we used identifiable neurons in a neurobiological model system, the mollusc Aplysia, to study neuropeptides, a diverse class of neuromodulators. We took advantage of two types of feeding neurons, B48 and B1/B2, in the Aplysia buccal ganglion that might contain different neuropeptides. We performed a representational difference analysis (RDA) by subtraction of mRNAs in B48 versus mRNAs in B1/B2. The RDA identified an unusually long (2025 amino acids) peptide precursor encoding Aplysia leucokinin-like peptides (ALKs; e.g. ALK-1 and ALK-2). Northern blot analysis revealed that, compared with other ganglia (e.g. the pedal-pleural ganglion), ALK mRNA is predominantly present in the buccal ganglion, which controls feeding behavior. We then used in situ hybridization and immunohistochemistry to localize ALKs to specific neurons, including B48. MALDI-TOF MS on single buccal neurons revealed expression of 40 ALK precursor-derived peptides. Among these, ALK-1 and ALK-2 are active in the feeding network; they shortened the radula protraction phase of feeding motor programs triggered by a command-like neuron. We also found that this effect may be mediated by the ALK-stimulated enhancement of activity of an interneuron, which has previously been shown to terminate protraction. We conclude that our multipronged approach is effective for determining the structure and defining the diverse functions of leucokinin-like peptides. Notably, theALKprecursor is the first verified nonarthropod precursor for leucokinin-like peptides with a novel, marked modulatory effect on a specific parameter (protraction duration) of feeding motor programs. [ABSTRACT FROM AUTHOR]

The article presents a study which investigates the cloning and prokaryotic expression of gam82 gene of Eimeria maxima neurotrphin (NT) strain and its immunology.