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A [6 + 3] annulation reaction of Morita-Baylis-Hillman carbonates and dicyanoheptafulvene is accomplished by employing commercially available triphenylphosphine as the Lewis base catalyst. A spectrum of densely functionalized bicyclo[4.3.1]decane architectures are efficiently constructed with exclusive diastereoselectivity and good yield (up to 95%).

Rapid microwave hydrothermal synthesis is carried out to obtain hierarchical Mn2O3 microsphere through a self-assembled process within 30 minutes. All the raw materials used is nontoxicity without any template or polymer and the side-products are all small molecules which abide by the pricnciple of environmental protection. After the following solid state reaction, the as-prepared Mn2O3 powders can still keep the hierarchical morphology of micro sphere which is consisted of small primary particles and secondary slices. The sample obtained at 600 °C with high crystallinity, large specific surface area and mesoporous exhibits best electrochemical performances. High specific capacity of 921.6 mAh g−1 could be reached at a current density of 200 mA g−1. An interesting phenomenon with abnormal capacity increasing appears which could be ascribed to the continual enhancement of interface Li-storage. Thus, high specific capacity of about 525 mAh g−1 is obtained at high current density of 1000 mA g−1 after 500 cycles. Furthermore, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) are performed to further study the hierarchical Mn2O3 anode material. It is revealed that such rapid microwave synthesis without any contamination is considered as a promising way to obtain hierarchical manganese oxides as anode material for applications.

Chronic renal allograft dysfunction (CRAD) is the most common cause of graft failure following renal transplantation. However, the underlying mechanisms remain to be fully elucidated. Immunosuppressants and hyperlipidemia are associated with renal fibrosis following long-term use. The present study aimed to determine the effects of tacrolimus (FK506) and lipid metabolism disorder on CRAD. In vitro and in vivo models were used for this investigation. Cells of the mouse proximal renal tubular epithelial cell strain, NRK-52E, were cultured either with oxidized low-density lipoprotein (ox-LDL), FK506, ox-LDL combined with FK506, or vehicle, respectively. Changes in cell morphology and changes in the levels of lectin-like ox-LDL receptor-1 (LOX-1), reactive oxygen species (ROS), hydrogen peroxide and fibrosis-associated genes were evaluated at 24, 48 and 72 h. In separate experiment, total of 60 Sprague-Dawley rats were divided randomly into four groups, which included a high-fat group, FK506 group, high-fat combined with FK506 group, and control group. After 2, 4 and 8 weeks, the serum lipid levels, the levels of ox-LDL, ROS, and the expression levels of transforming growth factor (TGF)-β1 and connective tissue growth factor were determined. The in vitro and in vivo models revealed that lipid metabolism disorder and FK506 caused oxidative stress and a fibrogenic response. In addition, decreased levels of LOX-1 markedly reduced the levels of TGF-β1 in the in vitro model. Taken together, FK506 and dyslipidemia were found to be associated with CRAD following transplantation.

In tumor microenvironment, interactions among multiple cell types are critical for cancer progression. To understand the molecular mechanisms of these complex interplays, the secreted protein analysis between malignant cancer cells and the surrounding nonmalignant stroma is a good viewpoint to investigate cell-cell interactions. Here, we developed two stable isotope labeling of amino acids in cell culture (SILAC)-based mass spectrometry (MS)/MS approaches termed spike-in SILAC and triple-SILAC to quantify changes of protein secretion level in a cell co-cultured system. Within the co-culture system of CT26 and Ana-1 cells, the spike-in SILAC and triple-SILAC MS approaches are sensitive to quantitatively measure protein secretion changes. Three representative quantified proteins (Galectin-1, Cathepsin L1 and Thrombospondin-1) by two SILAC-based MS methods were further validated by Western blotting, and the coming result matched well with SILACs’. We further applied these two SILACs to human cell lines, NCM460 and HT29 co-culture system, for evaluating the feasibility, which confirmed the spike-in and triple SILAC were capable of monitoring the changed secreted proteins of human cell lines. Considering these two strategies in time consuming, sample complexity and proteome coverage, the triple-SILAC way shows more efficiency and economy for real-time recording secreted protein levels in tumor microenvironment.

Three aluminum wires with different melted mark, which were found inside a burned distribution board from the electrical fire debris in rural areas of Northeast China were characterized to determine the cause of fire. By visual and microstructure/metallographic analysis, one melted bead shows typical morphology (microstructure/characteristics) as a result of overheating or electric short circuit (ESC) arc beads which was identified as the most possible ignition source. The macro-/micro-structure of the metallic wire, the chemical composition of the beads surface and the state of the polymer insulating sheath combining the tension state of the electric wire provided solid evidence on the exposure temperature and time of each aluminum wire. Consequently, the fire source was identified. Therefore, the characterization on the macro-/micro-structure and chemical composition of metallic surface with scientific technique is greatly helpful in determining heating process of metallic parts and subsequently the cause of fire.

Arabidopsis heat shock factor HsfA1a is present in a latent, monomeric state under normal conditions; its activation involves heat stress-induced trimerization, binding to heat shock element in target promoters, and the acquisition of transcriptional competence. HsfA1a is an important regulator for heat stress-induced gene expression and thermotolerance. However, it is not clear whether HsfA1a is directly activated by stress and the mechanisms of the stress signaling are poorly understood. We analyzed HsfA1a activation by trimerization and DNA-binding assays in vitro and in vivo in response to heat stress, low/high pH, and hydrogen peroxide treatments. Our results show that purified recombinant HsfA1a was activated by these stress treatments in vitro. The same treatments also induced the binding to HSP18.2 and HSP70 promoters as examined by chromatin immunoprecipitation, and the HsfA1a DNA binding paralleled the mRNA expression of its target genes induced by different stresses. Stress-induced DNA-binding could be reversed, both in vitro and in vivo, by subsequent incubation with reducing agents (DTT, NADPH). These data suggest that HsfA1a can directly sense stress and become activated, and this process is dependent on the redox state. An N-terminal deletion of the amino acid residues from 48 to 74 negatively affected pH- and hydrogen peroxide-, but not heat-stress sensing.

Recent studies using quantum mechanics energy decomposition methods, for example, SAPT and ALMO, have revealed that the charge transfer energy may play an important role in short ranged inter-molecular interactions, and have a different distance dependence comparing with the polarization energy. However, the charge transfer energy component has been ignored in most current polarizable or non-polarizable force fields. In this work, first, we proposed an empirical decomposition of SAPT induction energy into charge transfer and polarization energy that mimics the regularized SAPT method (ED-SAPT). This empirical decomposition is free of the divergence issue, hence providing a good reference for force field development. Then, we further extended this concept in the context of AMOEBA polarizable force field, proposed a consistent approach to treat the charge transfer phenomenon. Current results show a promising application of this charge transfer model in future force field development. © 2017 Wiley Periodicals, Inc.

This study reports the synthesis of ZnAl 2 O 4 (ZAO) nanocrystallites with various degrees of crystal quality using high-temperature annealing of efficiently cross-linked ZnO–Al 2 O 3 core–shell nanowires. The effects of annealing temperature on the formation of ZAO nanocrystallites from ZnO–Al 2 O 3 core–shell nanowires were investigated. X-ray diffraction patterns revealed the cubic spinel phase structure of the ZAO nanocrystallites. Scanning electron microscopy images revealed that the ZnO–Al 2 O 3 core–shell nanowires annealed at a high temperature exhibited a rugged surface, which is associated with the formation of the ZAO phase. Transmittance electron microscopy analysis showed that the crystalline quality of each ZAO nanograin formed at 800 °C was inhomogeneous, and most of the ZAO phase exhibited unsatisfactory crystalline quality; however, those formed at 1000 °C exhibited excellent crystalline quality. The nanowires annealed at 1000 °C exhibited a strong UV band emission (3.25 eV), as well as a marked visible emission band at 2.75 eV.

Tumor growth without size restriction depends on vascular supply. The ability of tumor to induce new blood-vessel formation has been a major focus of cancer research over the past decade. It is now known that members of the vascular endothelial growth factor and angiopoietin families, mainly secreted by tumor cells, induce tumor angiogenesis, whereas other endogenous angiogenic inhibitors, including thrombospondin-1 and angiostatin, keep tumor in dormancy. Experimental and clinical evidence has suggested that the process of tumor metastasis depends on angiogenesis or lymphangiogenesis. This article summarizes the recent research progress for some basic pro- or anti-angiogenic factors in tumor angiogenesis.