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Due to their features of low cost, good corrosion resistance and environmental friendliness, transition metal oxides/nitrides are among the most promising materials for energy storage and conversion. Meanwhile, graphitic carbon nitride is a non-metallic polymer that has been widely used in the environmental and energy conversion fields due to its abundant precursor species and simple process of synthesis. In this study, an amorphous carbon nitride/NiO/CoN-based composite (Ni-Co-CN) is in situ fabricated via simple one-step pyrolysis; it displays high capacitive performance and efficient electrocatalytic capability for the oxygen evolution reaction (OER). Specifically, the optimized Ni-Co-CN electrode shows an ultra-high areal specific capacitance of 18.8 F cm-2 at 2 mA cm-2 in 3 M KOH electrolyte, and it retains 91.4% of its areal specific capacitance even after 10 000 cycles of CV scans. Upon being used as an electrocatalyst in the OER process, the overpotential of Ni-Co-CN can reach 195 mV versus a reference hydrogen electrode (RHE) at 10 mA cm-2, which is far lower than those of most reported Ni/Co-based catalysts. Additionally, the potential loss of Ni-Co-CN electrode is less than 1% after a long-term durability test over 60 h. The experimental results integrated with density functional theoretical calculations reveal that the excellent performance of the Ni-Co-CN self-supported electrode can be ascribed to the fast redox reduction of multi-valent transition metal ions, abundant surface defects and plentiful nano-scaled porous structures. This work provides a promising strategy for exploring methods to combine economic Ni/Co-based compounds with carbon-based materials to obtain low-cost yet efficient electrode materials for electrochemical energy storage and conversion.

Mesenchymal stem cells (MSCs) are widely used to treat and prevent liver ischemia–reperfusion injury (LIRI), which commonly occurs after liver surgery. Lin28 is an RNA-binding protein crucial for early embryonic development, stem cell differentiation/reprogramming, tumorigenesis, and metabolism. However, whether Lin28 can enhance metabolism in human placental MSCs (PMSCs) during hypoxia to improve the protective effect against LIRI remains unclear. First, a Lin28 overexpression construct was introduced into PMSCs; glucose metabolism, the expression of glucose metabolism - and PI3K-AKT pathway-related proteins, and the levels of microRNA Let-7 family members were examined using a glucose metabolism kit, western blots, and real-time quantitative PCR, respectively. Next, treatment with an AKT inhibitor was performed to understand the association of Lin28 with the PI3K-Akt pathway. Subsequently, AML12 cells were co-cultured with PMSCs to construct an in vitro model of PMSC protecting liver cells from hypoxia injury. Finally, C57BL/6J mice were used to establish a partial warm hepatic ischemia–reperfusion model in vivo. Lin28 increased the glycolysis capacity of PMSCs, allowing these cells to produce more energy under hypoxic conditions. Lin28 also activated PI3K-Akt signaling under hypoxic conditions, and AKT inhibition attenuated the effects of Lin28. In addition, Lin28 overexpression was found to protect cells against LIRI-induced liver damage, inflammation, and apoptosis and attenuate hypoxia-induced hepatocyte injury. Inconclusion, Lin28 enhances glucose metabolism under hypoxic conditions in PMSCs, thereby providing protective effects against LIRI via the activation of the PI3K-Akt signaling pathway. Our study first reported the application of gene-modified mesenchymal stem cell-based therapy in LIRI.

Odd-numbered primary alcohols are components of plant cuticular wax, but their biosynthesis remains unknown. We isolated a rice wax crystal-sparse leaf 5 (WSL5) gene using a map-based cloning strategy. The function of WSL5 was illustrated by overexpression and knockout in rice, heterologous expression in Arabidopsis and transient expression in tobacco leaves. WSL5 is predicted to encode a cytochrome P450 family member CYP96B5. The wsl5 mutant lacked crystalloid platelets on the surface of cuticle membrane, and its cuticle membrane was thicker than that of the wild-type. The wsl5 mutant is more tolerant to drought stress. The load of C23 -C33 alkanes increased, whereas the C29 primary alcohol reduced significantly in wsl5 mutant and WSL5 knockout transgenic plants. Overexpression of WSL5 increased the C29 primary alcohol and decreased alkanes in rice leaves. Heterologous expression of WSL5 increased the C29 primary alcohol and decreased alkanes, secondary alcohol, and ketone in Arabidopsis stem wax. Transient expression of WSL5 in tobacco leaves also increased the production C29 primary alcohol. WSL5 catalyzes the terminal hydroxylation of alkanes, yielding odd-numbered primary alcohols, and is involved in the formation of epidermal wax crystals on rice leaf, affecting drought sensitivity.

Mesoporous silica is a drug carrier with strong targeting, large loading capacity, and easy modification of its surface while its toxicity draws increasing attention recently. In this study, we evaluated the impact of SBA-15 nanomaterials on hippocampal neurons. We found that SBA-15 induces oxidative damage to hippocampal neurons HT22, which further activates autophagy. Treatment with the mammalian target of rapamycin (mTOR) inhibitor AZD8055, the phosphorylation level of mTOR and P70S6K reduced and increased levels of p-AMPK meaning that the adenosine-activated protein kinase (AMPK)/mTOR/P70S6K pathway is involved in SBA-15 induced autophagy of HT22. These results suggested that mesoporous silica material SBA-15 might affect central nervous cells via oxidative stress activation of the AMPK/mTOR/P70S6K pathway, which provides a theoretical basis for safe administration of such materials in patients.

Three-dimensional (3D) nanofibrous structured Al2O3 was successfully synthesized using the poly (vinyl alcohol) (PVA) polymer-assisted freeze-drying method, and a series of factors that influence fiber performance were investigated in depth. PVA nanofibers were also investigated for the first time. The surface morphology, structure, and other properties of PVA nanofibers, precursor Al2O3/PVA nanofibers, and calcined Al2O3 nanofibers were characterized by scanning electron microscopy, X-ray diffraction, and nitrogen adsorption measurements. The results showed that Al2O3 nanofibers with good performances could be obtained at the optimum conditions where the precursor solution was prepared by boehmite nanoparticles (0.01 wt%) and PVA (0.1 wt%, DP = 500) with a mass ratio of 7: 3, followed by the use of the rapid freezing method at −196 °C under liquid nitrogen in the pre-frozen process; subsequently, calcination was performed at 500 °C for 5 h to form Al2O3 nanofibers. The increasing calcination temperature (500 °C–1300 °C) enabled the transformation of the Al2O3 crystalline phase from γ-Al2O3 to α-Al2O3. It also improved the specific surface area from 44.5 m2 g−1 for the precursor Al2O3/PVA nanofibers to 263.4 m2 g−1 for the Al2O3 nanofibers calcinated at 500 °C. However, an excessive calcination temperature at 1300 °C was detrimental to the specific surface area, presumably due to sintering or blocking by metal particles. This work provides optimum conditions that make Al2O3 nanofibers valuable for further development, and it has the potential for industrial applications.

A synthetic technique based on electrospinning in conjunction with the sol–gel method and thermal treatment was employed to fabricate Pd(II)-doped SiO2/Fe2O3 nanofibers (NFs) with different Pd(II) doping amounts. These materials were evaluated for their catalytic ability in the ethanol dehydration reaction. Interestingly, the coexistence of the mixed-phase structure α-/γ-Fe2O3 indicates that the Pd(II) dopant inhibits the γ-Fe2O3-to-α-Fe2O3 phase transformation even under high-temperature thermal treatment. A higher reaction temperature is more beneficial to facilitate catalytic activity than a lower temperature. The catalytic reaction is improved upon adding Pd(II), probably due to the enhancement of the lattice oxygen mobility in the presence of Pd(II) in SiO2/Fe2O3. As the Pd(II) doping increases, the catalytic activity is gradually promoted. For 0.15 wt% Pd(II)-doped SiO2/Fe2O3 NFs produced at a reaction temperature of 670 °C, the ethanol conversion reaches a maximum value of 15.9%, and the selectivity of ethylene is 96.2%. It is inferred that a larger total proportion of active oxygen species, including lattice oxygen and surface chemisorbed oxygen, can better generate a strong catalytic reaction.

In this work, silica/ferric oxide nanofibers (SiO2/Fe2O3 NFs) have been successfully synthesized by electrospinning technique, sol-gel method and thermal treatment in combination with controlling the composite solutions in different ratio. The results show that some significant influences on the morphologies, structures and properties of the SiO2/Fe2O3 NFs exhibit a synergistic effect of SiO2 and Fe2O3. Typically, compared with the BET specific surface area of pure SiO2 NFs (2.0 m2 g−1) and pure Fe2O3 NFs (5.1 m2 g−1), a remarkably larger BET specific surface area is found to be 289.6 m2 g−1 for 32-SiO2/Fe2O3 NFs (with a ratio of 32% Fe2O3) with mesoporous structure of 3.2 nm due to the increase of active positions. It also corresponds to the NH3-TPD results of a higher amount of acid centers about 93 μmol g−1 for 32-SiO2/Fe2O3 NFs than 4.5 μmol g−1 for pure SiO2 NFs and 2.9 μmol g−1 for pure Fe2O3 NFs.

Lycium barbarum polysaccharides (LBP) are the major ingredients of wolfberry. In this study, we investigated the role of LBP in endothelial dysfunction induced by oxidative stress and the underlying mechanisms using thoracic aortic endothelial cells of rat (RAECs) as a model. We found that Ang II inhibits cell viability of RAECs with 10[Formula: see text][Formula: see text]mol/L of Ang II treatment for 24[Formula: see text]h most potential ([Formula: see text]), the level of reactive oxygen species (ROS) is increased by Ang II treatment ([Formula: see text]), and the expression of Occludin and Zonula occludens-1 (ZO-1) is decreased by Ang II treatment ([Formula: see text]). However, preincubation of cells with LBP could inhibit the changes caused by Ang II, LBP increased cell viability ([Formula: see text]), decreased the level of ROS ([Formula: see text]), and up-regulated the expression of Occludin ([Formula: see text]) and ZO-1. In addition, Ang II treatment increased the expression of EGFR and p-EGFR (Try1172) and which can be inhibited by LBP. On the contrary, expression of ErbB2, p-ErbB2 (Try1248), PI3K, p-e-NOS (Ser1177) ([Formula: see text]), and p-AKT (Ser473) ([Formula: see text]) was inhibited by Ang II treatment and which can be increased by LBP. Treatment of the cells with inhibitors showed that the regulation of p-e-NOS and p-AKT expression by Ang II and LBP can be blocked by PI3K inhibitor wortmannin but not EGFR and ErbB2 inhibitor AC480. Taken together, our results suggested that LBP plays a critical role in maintaining the integrality of blood vessel endothelium through reduced production of ROS via regulating the activity of EGFR, ErbB2, PI3K/AKT/e-NOS, and which may offer a novel therapeutic option in the management of endothelial dysfunction.

Mesoporous silica is widely used because of its unique and excellent properties, especially it can be used as a drug carrier and gene carrier in the biomedical field. After the mesoporous silica is put into clinical use, it is more likely to be exposed in human body. Therefore, the effect of mesoporous silica on human body cannot be ignored. The injury of vascular endothelial cells is a prerequisite for the occurrence of many cardiovascular diseases. As a drug and gene carrier, mesoporous silica increases its contact with vascular endothelial cells, so its toxic effect on cardiovascular system cannot be ignored. In this study, amino (NH2 ) and carboxyl (COOH) were modified on mesoporous silica SBA-15 by post-grafting. The results showed that it still maintained the one-dimensional hexagonal mesoporous structure of SBA-15 and had typical mesoporous structure. Then human umbilical vein endothelial cells (HUVECs) were infected with SBA-15, NH2 -SBA-15, and COOH-SBA-15. The results showed that the functionalized mesoporous silica SBA-15 had cytotoxicity to HUVECs and damaged the cell membrane, but compared with the unmodified mesoporous silica SBA-15 the cytotoxicity of functionalized mesoporous silica SBA-15 was lower and the toxicity of carboxyl modified group was the lowest. By comparing the cell inhibition rate and the expression level of lactate dehydrogenate and reactive oxygen species induced by the three materials, oxidative damage and cell membrane damage may be two mechanisms of cytotoxicity. Mesoporous silica SBA-15 has an effect on cardiovascular system by inducing the high expression of nitric oxide, intercellular adhesive molecule-1 and vascular cell adhesive molecule-1 in HUVECs. In summary, our results show that mesoporous silica is toxic to vascular endothelial cells.

It is an enormous challenge to achieve highly efficient organic room-temperature phosphorescence (RTP) with a long lifetime. We demonstrate that, by bridging the carbazole and halogenated phenyl ring with a methylene linker, RTP phosphors CzBX (X=Cl, Br) present high phosphorescence efficiency (ΦPh ). A ΦPh up to 38 % was obtained for CzBBr with a lifetime of 220 ms, which is much higher than that of compounds CzPX (X=Cl, Br) with a C-N bond as a linker (ΦPh

Paraquat (PQ) is associated with multiple nervous system disorders including Parkinson's disease. Despite the evidence that PQ could induce inflammatory responses in the central nervous system and largely contribute to neurotoxicity, the mechanisms of PQ-induced neuroinflammation are not yet fully understood. Toll-like receptor 4 (TLR4) could recognize various pathogens and initiate inflammation processes. Therefore, we investigated the role of TLR4 in PQ-induced neuroinflammation by using murine microglial immortalized BV-2 cell line. Normal microglia and TLR4-knockdown microglia were treated with PQ to evaluate signal transduction molecular expression, inflammatory responses, and microglial functions. Compared with normal microglia, PQ-induced production of pro-inflammatory cytokines was significantly reduced in TLR4-knockdown microglia. Levels of M1 markers were decreased, while levels of M2 markers were increased upon PQ exposure, confirming that TLR4 depletion inhibited the microglial M1 polarization. Besides, the migration and phagocytosis capability reduced by PQ were to some extent recovered in TLR4-knockdown microglia. Taken together, our results suggested that TLR4 mediated the neuroinflammatory responses in microglia and the depletion of TLR4 protects against PQ neurotoxicity.

The flotation performance and hydrophobic mechanism of O-ethyl-N-benzoyl thionocarbamate (EBZTC) on chalcopyrite were first estimated by single flotation experiments, batch adsorption experiments, contact angle measurements, DFT calculation and FTIR analysis. Single flotation experiments illustrated that a flotation recovery of 96.7% was achieved to chalcopyrite when EBZTC was used compared to 90% with SIBX at pH 6.5. Adsorption experiments indicated that the adsorption process of EBZTC on chalcopyrite surface was an exothermic monolayer chemisorption process. Hydrophobic mechanism demonstrated that EBZTC chemisorbed onto the chalcopyrite surface through the chemical reactions of C O and C S groups to the copper species with the formation of C O Cu and C S Cu bonds, which resulted in the coverage of the hydrophobic groups of EBZTC onto the chalcopyrite surface to enhance its hydrophobicity.

Bone regeneration strategies rely on biomaterial constructs with stem cells or growth factors. By comparison, cell homing strategies employ chemokines to recruit the host endogenous stem or progenitor cells to the defect site to support endogenous healing. In the present study, we used a novel fluffy hydroxyapatite/polyacrylonitrile (HA/PAN) composite scaffold to provide a better three-dimensional cell culture microenvironment. These HA/PAN composite scaffolds loaded with stromal cell-derived factor-1α (SDF-1α) provided a diffusion-controlled SDF-1α release profile and endowed the scaffolds with cell homing capabilities. Furthermore, the scaffolds significantly stimulated bone marrow stromal cell (BMSC) recruitment, facilitated BMSC osteogenic differentiation, and promoted ectopic bone formation. Our results suggest that a HA/PAN composite scaffold loaded with SDF-1α offers a clinically beneficial bone repair strategy.

Lipid vesicles are an attractive model membrane experimental platform that is widely used in a biological context. The stability of vesicles can affect their performance and depends on various experimental conditions. How bio-related ions affect vesicle morphology is poorly understood in some cases. Herein, we investigated changes in vesicle morphology influenced by cation in the static and flowing environments. The effects of different mono- and di-valent metal cations on the morphology of lipid vesicles were systematically studied using the various techniques. The results showed that divalent cations caused significant aggregation or fusion of lipid vesicles, but monovalent cations had little effect on the vesicle morphology. Cation binding increased the net surface potential of vesicles, leading to changes in the zeta potential. The same qualitative kinetics were observed for cations that had the same valence at the same ionic strength. However, different types of cations gave different quantitative effects. The order of the ability to destroy the vesicle morphology was Cu2+ > Mg2+ > Ca2+ > Na+ > K+. These results are of practical value in the use of lipid vesicles as a bionic model, and help to shed light on the role of ions at membrane surfaces and interfaces.

A facile hydrothermal method is developed to prepare hierarchical dahlia-like SnO2 nanostructures (HDSNs). They have been successfully synthesized without using any templates or surfactants. We find that the hierarchical architectures of SnO2 are assembled by a number of regular-shaped nanosheets and nanoparticles, which are cross-linked in the interior of the micro-flower. Based on the nucleation and self-assembly process, a possible formation mechanism is proposed. The effect of NaCl on the product is also studied. In addition, the product exhibits excellent photocatalytic activity to Rhodamine B (RhB) aqueous solution and possess good stability and reusability under visible light. This study will provide valuable experimental data for further study of nanomaterials and their photocatalytic properties.

TiO2 thin film was deposited by Plasma Assisted Chemical Vapor Deposition (PECVD), and TiOx (0

Plant growth and development are highly coordinated by hormones, including brassinosteroid (BR) and gibberellin (GA). Although much progress has been made in understanding the fundamental signaling transduction in BR and GA, their relationship remains elusive in rice. Here, we show that BR suppresses the level of OsmiR159d, which cleaves the target OsGAMYBL2 gene. The OsmiR159d-OsGAMYBL2 pair functions as an early BR-responsive module regulating the expression of BU1, a BR-regulated gene involved in BR signaling, and CPS1 and GA3ox2, two genes in GA biosynthesis, by binding to the promoters of these genes. Furthermore, OsGSK2, a key negative player in BR signaling, interacts with OsGAMYBL2 and prevents it from being degraded under 24-epibrassinolide treatment, whereas SLR1, a rice DELLA protein negatively regulating GA signaling, interacts with OsGAMYBL2 and prevents OsGAMYBL2 from binding to the target gene promoter. GA signaling induces degradation of OsGAMYBL2 and, consequently, enhances BR signaling. These results demonstrate that a BR-responsive module acts as a common component functioning in both BR and GA pathways, which connects BR signaling and GA biosynthesis, and thus coordinates the regulation of BR and GA in plant growth and development.

Novel three-dimensional octagonal-like CuO micro-/nanostructures with diameters ranging from 10 to 15 μm have been successfully prepared by hydrogen peroxide-assisted hydrothermal method and subsequent calcination. The product morphology can be changed by simply ordering the amount of hydrogen peroxide (H2O2). When the amounts of H2O2 is increased, the length of the corner portion is increased and the width is narrower. The obtained octagonal CuO nanostructures were evaluated for their ability for the degradation of hazardous organic contaminants in water under visible-light irradiation. Comparing with commercial CuO and other CuO products, the CuO octagonal nanostructures exhibit excellent performance for photocatalytic decomposition of RhB (Rhodamine B). It is well established that effective photocatalytic performance results from its unique 3D octagonal nanostructures. We believe that the present work will provide some ideas for further fabrication of other novel nanostructures and exploration of their applications.

A novel graphene oxide (GO) immobilized quaternized polysulfone (PSF) hybrid membrane (Q-PSF/GO) was prepared via phase inversion method using GO as an additive, and triethanolamine (TEOA) as an aminated agent. TEOA, which reacted with both PSF and GO, could improve the dispersibility and compatibility of GO in membrane casting solution. The membrane exhibited highest permeability and rejection rate to bovine serum albumin (BSA) compared to bare PSF membrane and PSF/GO membrane. Expressly, when the same amount of GO was incorporated into the PSF/GO membrane and the Q-PSF/GO membrane, the Q-PSF/GO membrane showed a more satisfactory performance. The water contact angle measurement confirmed the increased hydrophilicity of the Q-PSF/GO hybrid membrane. FE-SEM images proved that the Q-PSF/GO 0.5 membrane possessed larger and more vertical finger-like pore structure in comparison with bare PSF membrane and PSF/GO membrane. Furthermore, it was proved by CLSM images that a thick and incompact layer of BSA was absorbed onto the surface of the Q-PSF/GO 0.5 membrane. However, the absorbed layer of BSA on Q-PSF/GO 0.5 membrane surface could be easily washed away compared to the bare PSF membrane.

The uniform hexagonal cone-like Cu2O nanostructures (HCCNs) which of the diameter is about 500 nm, have been successfully prepared via an ultrasound-assisted method. Due to the effects of sonication, the Cu2O nanostructures are composed of numerous nanoparticles. A possible growth mechanism is proposed as nucleation and growth of small primary nanoparticles through an oriented attachment mechanism. By investigating the effects of experimental conditions, it is found that the volume ratio of N,N-dimethylformamide (DMF)/deionized water and the time of sonication treatment turned out to be important parameters for the control of morphology of Cu2O. Moreover, compared with other Cu2O products, the HCCNs exhibits excellent photocatalytic activity for the photodegradation of hazardous organic contaminants in water such as phenol and Rhodamine B (RhB) under visible light irradiation. It is believed that this phenomenon is originated from the HCCNs unique nanostructure and its larger surface areas, leading to its high utilization rate of visible light. Based on the experimental results, mechanism for the degradation of phenol and RhB can be proposed.

Large forming voltages, low resistive and magnetic switching ratios and poor reversibility have impeded the practical applications of electrical manipulation of magnetic properties through a resistive switching process. Here we show that all above parameters can be improved greatly through Co doping in Ti/TiO 2 /Pt device. A comparison of different mechanism of electrically controlled nonvolatile ferromagnetism in Co-doped and undoped TiO 2 films is proposed. These results will provide a fundamental understanding for the electrically control of ferromagnetism in doped and undoped metal-oxide films and may be extended to certain materials in addition to Co doped TiO 2 .

3D hierarchical WO 3 ·0.33H 2 O microspheres have been successfully synthesized by one-pot solvothermal method at the temperature of 160 °C. The hierarchical WO 3 ·0.33H 2 O microspheres are composed of many slices with jagged edges, with side length of 100–300 nm and a thickness of about 50 nm. K 2 SO 4 , as a directing agent, plays an important role in controlling the morphology of WO 3 ·0.33H 2 O samples. In addition, a series of time-dependent tests have been listed, by which we can obtain the morphological evolution of hierarchical WO 3 ·0.33H 2 O microspheres. Moreover, the products exhibit excellent photocatalytic activity for the photodegradation of Rhodamine B (RhB) under visible light irradiation.

We have studied the intra- and inter-molecular chirogenesis events on a family of chiral bisporphyrin hosts H1-H3 . The three pairs of enantiomers for H1-H3 were constructed by connecting two zinc(II) porphyrinates to a homochiral ( R )-(+)- or ( S )-(−)-1,1′-bi-2-naphthol (BINOL) with ester or ether linkages. Split Cotton effects were observed for all of the bisporphyrin hosts. For each enantiomer, the sign of the bisignate CD couplets directly correlates to the stereostructure of the BINOL linker, namely a ( R )-BINOL linker leads to a negative CD couplet and vise versa . The CD intensities of the hosts are decreasing from H1 to H3 along with the increasing of the length and flexibility of the chemical linkages between BINOL and porphyrin subunits. The predictable CD signs and regularly changed CD intensities demonstrate the defined intramolecular asymmetric information transfer, by which the chirality of a BINOL linker is translated to a preferred chiral twist in the inter-porphyrin arrangement with tunable efficiency. Furthermore, the intermolecular binding of 4,4′-BiPyridyl (BiPy), as a typical achiral ditopic guest, to the series of hosts were detected by UV–Vis, 1 H NMR and CD spectroscopic titrations. The results indicate a convergent and complementary 1:1 binding mode, in which a BiPy ligand binds to a host molecule by ditopic Zn N coordination forming a stable cyclic supramolecular complex. In particular, the intensity of CD signals decreases significantly for all of the supramolecular complexes in comparison with the chiral bisporphyrin hosts alone, though the CD sign does not change. The observation is rationalized by DFT molecular modeling, which suggests that upon the formation of 1:1 cyclic supramolecular complexes the chiral twist direction of the two porphyrin moieties does not change, while the Zn Zn distance increases remarkably. The present results highlight the effects of intramolecular chirality induction and intermolecular chirality modulation in BINOL bridged porphyrin tweezer systems.

Paraquat (PQ), a widely characterized neurotoxicant, has been generally accepted as one of the environmental factors in the etiology of Parkinson’s disease (PD). Despite the direct evidence that PQ could induce inflammatory responses in central nervous system, the putative adverse effects of PQ on the neuroimmune interactions have rarely been investigated. High-mobility group box 1 (HMGB1) has been proven to be relevant to the neuroinflammation involved in PD; however, whether and how HMGB1 exerts modulatory effects in nervous system upon PQ exposure remain elusive. Therefore, the present study investigated the underlying association between HMGB1 and PQ exposure in SH-SY5Y cells, which is a well-established in vitro model for PD research. We observed that HMGB1 was markedly increased in a concentration and time-dependent manner upon PQ exposure, and the elevated HMGB1 could be translocated into cytosol and then released to the extracellular milieu of SH-SY5Y cells. Knockdown of HMGB1 inhibited the activation of RAGE-P38-NF-κB signaling pathway and the expression of inflammation cytokines such as TNF-α and IL-6. These results suggested that HMGB1 is involved in the PQ-induced neuron death via activating RAGE signaling pathways and promoting neuroinflammatory responses.

The objective of the present study was to explore the effects of environmental chemicals, such as methyl mercury, paraquat, and bisphenol A, on cell proliferation and apoptosis, as well as the expression levels of neuronal differentiation-related genes in neural stem cells (NSCs). NSCs originated from human umbilical cord blood (HUCB-NSCs) were used as cell models in the current study. CCK-8 and flow cytometry experiments were performed to assess the effects of methyl mercury, paraquat, and bisphenol A on the proliferation and apoptosis of HUCB-NSCs at different processes, including proliferation and differentiation stages. The expressions of neuronal differentiation-related genes were determined by reverse transcription-polymerase chain reaction and western blot analysis. The results showed that methyl mercury, paraquat, and bisphenol A treatments significantly inhibited cell proliferation and induced cell apoptosis in HUCB-NSCs, as well as decreased the expressions of Oct4, Gdf3, and Sox1, whereas increased Pax6 and Ngn1 expressions at both mRNA and protein levels. In conclusion, this study demonstrates that environmental chemicals can impair the proliferation and differentiation of NSCs, which may cause abnormal development of the nervous system.

Paraquat (PQ), a non-selective contact herbicide, has been generally accepted as one of the environmental neurotoxicants. Despite the direct evidence that PQ could induce inflammation responses in microglia, little is known about the effects of the inflammatory microglia on neurons. Thus in the present study, mouse primary cortical neurons and PC12 cells, widely-used in vitro neuron models for neurotoxicity research were applied to investigate the neuroinflammatory effects of PQ-activated microglia on neurons. We observed that the secretion levels of TNF-α and IL-6 in PC12 cells were markedly increased upon treatment with the supernatants of inflammatory BV2 microglia, and NF-κB p65 protein expression was also elevated. Specific inhibition of NF-κB by PDTC dramatically attenuated the increase of TNF-α and IL-6 release. These results suggested that PQ-induced inflammatory microglia exerts secondary inflammatory effects on neurons through activation of NF-κB pathway.

Anderson localization is a predominant phenomenon in condensed matter and materials physics. In fact, localized and delocalized states often co-exist in one material. They are separated by a boundary called the mobility edge. Mott transition may take place between these two regimes. However, it is widely recognized that an apparent demonstration of Anderson localization or Mott transition is a challenging task. In this article, we present a direct optical observation of a transition of radiative recombination dominant channels from delocalized (i.e., local extended) states to Anderson localized states in the GaInP base layer of a GaInP/GaAs single junction solar cell by the means of the variable-temperature electroluminescence (EL) technique. It is found that by increasing temperature, we can boost a remarkable transition of radiative recombination dominant channels from the delocalized states to the localized states. The delocalized states are induced by the local atomic ordering domains (InP/GaP monolayer superlattices) while the localized states are caused by random distribution of indium (gallium) content. The efficient transfer and thermal redistribution of carriers between the two kinds of electronic states was revealed to result in both a distinct EL mechanism transition and an electrical resistance evolution with temperature. Our study gives rise to a self-consistent precise picture for carrier localization and transfer in a GaInP alloy, which is an extremely technologically important energy material for fabricating high-efficiency photovoltaic devices.

Rare earth (RE) with specific application value has become the relatively important strategic resource for all countries. Weathered crust elution-deposited rare earth ore (WCED-REO) are rich in middle-heavy RE, and its exploitation restrict the global supply of the middle-heavy RE. The leaching technology directly determines the leaching efficiency of RE in WCED-REO. The selection and use of the leaching agents are the most important parts of the leaching technology. The leaching mechanism is at the core of the leaching technology and also affects the effective utilization of the leaching agents. The research and development of leaching technologies, leaching agents, and leaching mechanisms of WCED-REO are discussed in this article. The development processes of exiting leaching technologies are introduced. The advantages and disadvantages of barrel leaching, pool leaching, heap leaching, in-situ leaching, and other leaching technologies are compared. And the new and practical leaching technologies are put forward. The research progresses of ammonium salt leaching agents, composite ammonium salt leaching agents, and novel non-ammonium leaching agents in recent years are reviewed. The leaching effects of different leaching agents are compared comprehensively to provide guidance for industrial application and research direction of the best leaching agent in the later period. The leaching basic theory, as well as the mass transfer process and leaching kinetics of rare earth are introduced. The mass transfer processes in leaching mechanism are explained from the macroscopic and microscopic perspectives. The further research directions of the leaching technologies, leaching agents, and leaching mechanism of WCED-REO are put forward, which provide the theoretical guidance and technical supports for the green and efficient exploitation of WCED-REO.

Helix B surface peptide (HBSP) is an erythropoietin (EPO)-derived peptide that protects tissue from the risks of elevated blood pressure and thrombosis. This study focused on the protection of HBSP in hepatic ischaemia/reperfusion (I/R) by enhancing the level of autophagy. In detail, we randomly divided C57BL/6 mice into sham-operated, hepatic ischaemia/reperfusion (I/R), I/R + HBSP, I/R + HBSP + 3-methyladenine (autophagy inhibitor), I/R + HBSP + rapamycin (mTOR inhibitor), and I/R + HBSP + Ly294002 (Akt inhibitor) groups. We assessed alanine aminotransferase (ALT), aspartate aminotransferase (AST) and lactate dehydrogenase (LDH) levels in mouse sera, and performed haematoxylin/eosin (HE) staining, immunohistochemistry, electron microscopy, immunofluorescence microscopy, and western blotting on liver tissue to detect the degree of liver injury, liver apoptosis, autophagy, and the expression of microtubule associated protein 1 light chain 3 alpha (Map1lc3, or LC3), Beclin 1, phospho-mTOR, mTOR, phospho-Akt (P-Akt), and Akt. HBSP relieved hepatic I/R injury in a concentration-independent manner. The expression of LC3II, LC3I, and Beclin 1, and the formation of autophagosomes, in the I/R + HBSP group were higher than those in the I/R group. The protective effects of HBSP were abolished by 3-methyladenine and, to a lesser extent, Ly294002, but enhanced by rapamycin. Furthermore, In vivo, HBSP also protected against hypoxia injury induced by cobalt chloride (CoCl2) through improving the level of autophagy. Therefore, HBSP protected against hepatic I/R injury, mainly via regulating autophagy by targeting mTOR.

During the process of antioxidation of tert-butylhydroquinone (TBHQ) in oil and fat systems, tert-butylquinone (TQ) can be formed, which has higher toxicity than TBHQ. The changes of TBHQ and TQ in edible oils at room temperature (RT) or under thermal treatment were investigated. Under thermal treatment, volatilization was the main pathway of TBHQ loss in edible oils. TQ was the main oxidation product of TBHQ under thermal treatment as well as at RT. The amount of TQ in thermally treated oils was much less than that in oils stored at RT due to the decreased amount of oxygen dissolved in oils and easy volatilization of TQ at high temperature. In addition, TQ can be reduced to TBHQ by reduction components in edible oils, but the conversion amount was very small. Thus, TQ, theoretically having no antioxidative property, presented a very weak antioxidative activity equivalent to that of BHA due to the presence of insignificant amount of TBHQ formed from TQ in edible oils. The narrow potential difference of 0.059 between oxidation and reduction peaks of TBHQ and TQ resulted in easy interconversion of TBHQ and TQ under the action of common oxidation and reduction substances which have a higher oxidation potential or a lower reduction potential than they have.

A pair of 1,1'-binaphthalene-bridged bisporphyrins, (R)- and (S)-H1, were designed to examine their chiral discrimination abilities toward a range of model diamines by using UV-vis absorption, CD, and 1H NMR spectroscopy with the assistance of DFT molecular modeling. The spectroscopic titrations revealed that (R)-/(S)-H1 could encapsulate (R)-/(S)-DACH and (R)-/(S)-PPDA in the chiral bisporphyrin cavities, leading to the selective formation of sandwich-type 1:1 complexes via dual Zn-N coordination interactions. In particular, the chiral recognition energy (ΔΔG°) toward (R)-/(S)-DACH was evaluated to be -4.02 kJ mol-1. The binding processes afforded sensitive CD spectral changes in response to the stereostructure of chiral diamines. Remarkable enantiodiscrimination effects were also detected in the NMR titrations of (R)-/(S)-H1, in which the nonequivalent chemical shift (ΔΔδ) can reach up to 0.57 ppm for (R)-/(S)-DACH. However, due to the large steric effect, another chiral diamine ((R)-/(S)-DPEA) could not be sandwiched in the chiral bisporphyrin cavity; therefore, (R)-/(S)-DPEA could hardly be discriminated by (R)-/(S)-H1. The present results demonstrate a chiral bisporphyrin host with integrated CD and NMR chiral sensing functions and also highlight the binding-mode-dependent character of its enantiodiscrimination performance for different chiral guests.

Paraquat (PQ) is a widely characterized neurotoxicant able to induce a series of nervous system disorders, including neurobehavioral defects and neurodegenerative diseases. Despite the direct evidence that PQ could induce inflammatory responses in central nervous system and largely contribute to neurotoxicity, the putative adverse effects of PQ on the neuroimmune interactions have rarely been investigated. Therefore, the present study investigated underlying mechanisms of PQ-induced inflammatory response in BV-2 microglia cells. Proliferation, migration and phagocytosis of BV-2 cells upon PQ exposure were first investigated to demonstrate that PQ did stimulate BV-2 microglia into an active phenotype. Increased microglia M1 markers expression and decreased microglia M2 markers expression confirmed that PQ induces BV-2 cells towards M1 activation. The levels of pro-inflammatory cytokines were determined using ELISA and western blotting assays, showing that paraquat significantly promote the secretion of pro-inflammatory mediators such as tumor necrosis factor α (TNF-α), interleukin 1β (IL-1β) and interleukin 6 (IL-6). The up-regulation of TLR4/MyD88 protein expressions and enhanced translocation of NF-κB p65 protein upon PQ exposure were further demonstrated. Taken together, our results suggested that PQ induces M1 microglia polarization by increased production of pro-inflammatory molecules, which could be explained by the activation of the TLR4-mediated NF-κB signaling pathway.

Epoxides of soybean oil methyl esters (SMEs) are biodegradable, non-toxic, and renewable epoxy plasticizers. The objective of the present work was to investigate the effects of free fatty acids on the enzymatic epoxidation of SMEs. The results showed that the epoxidation of SMEs depended on the type of the added free fatty acid. For saturated (

The surface-initiated atom-transfer radical polymerization (ATRP) technique was applied to the graft polymerization of methyl methacrylate (MMA) and N -isopropylacrylamide (NIPAm) from three-dimensionally ordered macroporous cross-linked polystyrene (3DOM CLPS) on which the initiator, halogen atom was immobilized onto the pore wall of 3DOM CLPS by chloromethylation. FT-IR and TG-DWA analyses confirm that the graft polymerization of MMA and NIPAm via ATRP had been taken place at the pore wall of 3DOM CLPS. The initiating efficiency of chloromethyl groups was calculated according to the data of TGA-titration, revealed that the benzyl chloride is not only distributed on the surface of the pore walls but also must be present throughout the inner of the cross-linked polystyrene matrix. SEM analyses show that the grafted layers are smooth and homogeneous, and the ordered structure is well preserved after polymerization. By the adjustment of the graft polymerization time, the thickness of grafted polymer layers can be controlled. The max thickness of grafted PMMA layer is 85 nm and the max thickness of grafted PNIPAm layer is 35 nm.

The surface-initiated atom-transfer radical polymerization (ATRP) technique was applied to the graft polymerization of 2-hydroxyethyl methacrylate (HEMA) from three-dimensionally ordered macroporous crosslinked polystyrene (3DOM CLPS) on which the initiator (benzyl chloride) was immobilized onto the pore wall of 3DOM CLPS by chloromethylation of benzene ring. By the adjustment of the monomer concentration or graft polymerization time, the thickness of grafted polymer layers can be controlled. FTIR analysis confirms that the graft polymerization of HEMA via ATRP had been taken place at the pore wall of 3DOM CLPS. SEM images of PHEMA-grafted 3DOM CLPS show that the ordered structure is well preserved after graft polymerization and the grafted layers are dense and homogeneous. The maximum thickness of grafted layer is up to 35 nm and the corresponding percent weight increase is 102.8% in this study. Moreover, the PHEMA layers were further functionalized in high yield via their reactive hydroxyl groups under gentle condition. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 7950–7959, 2008

Three-dimensionally ordered macroporous polystyrene (3DOM PS) with pore size of 350 nm was fabricated using Cp2Co/ Ethyl 2-bromoisobutyrate (EBiB) catalytic system by ATRP. The resulting polymers were detected by FT-IR, 1H-NMR, SEM, and GPC. The microstructure of 3DOM PS was confirmed by FT-IR and 1H-NMR. SEM micrographs show that both silica spheres within the templates and pores in the 3DOM polystyrene are arranged in highly ordered fashion, and the shrinkage of the pores in the 3DOM PS is 24%. GPC curves show that the 3DOM PS possesses slightly lower Mn and narrow MWD compared with bulk one. This result indicats that living polymerization is different from non-living polymerizationin in the confined space.

A versatile method for the modification of three-dimensionally ordered macroporous (3DOM) highly syndiotactic polystyrene via chloromethylation at the pore walls has been demonstrated. This was followed by reaction with dimethylamine to establish a versatile approach to functionalization of such macroporous polymers. High syndiotacticity of 3DOM sPS is necessary for maintenance of the morphology of the original ordered pore structure after chloromethylation. The relative content of chloromethyl groups was shown to be 1.89 mmol/g3DOM sPS by TG-titration. The functionalized 3DOM sPS was characterized by SEM, FT-IR, and DSC to demonstrate that chloromethylation had occurred at the pore walls and that the dimethylamino moiety had replaced the chlorine atom of the chloromethyl group. DSC examination of the modified polymer indicated that the crystallinity of 3DOM sPS is little affected by functionalization. Thus the excellent properties of sPS are retained by the functionalized material. POLYM. ENG. SCI., 2009. © 2008 Society of Plastics Engineers

Three-dimensionally ordered macroporous polyethylenes (3DOM PE) with pore size ranging from 135 nm to 410 nm were prepared using supported catalysts on the surface of silica microsphere as template, followed infiltration of gaseous ethylene and polymerization. The morphology of 3DOM PE was characterized by SEM and the reflectance spectrum was recorded by UV–vis. It is shown that the pores are uniform, flexible and arranged in a highly ordered fashion. Reflectance spectrum of 3DOM PE also provided verification of the uniform nature of the sample. Moreover, the effect of confined space on polymerization was investigated by GPC and DSC. The results indicate that the porous PE possesses higher Mw compared with bulk PE, and exhibits lower melting temperature and crystallinity than those of bulk PE.

The aim of the present study was to explore the effects of continuous and intermittent exercise on the thoracic aortic vasoreactivity and free radical metabolism in rats fed with a high-fat diet (HD). Sprague-Dawley (SD) rats were randomly divided into four groups (n=8, each group): Conventional diet (CD), HD, HD with continuous exercise (HCE) and HD with intermittent exercise (HIE). HCE rats swam once/day for 90 min; HIE rats performed swimming exercises 3 times/day, 30 min each time with an interval of 4 h. In these two groups, the exercise was conducted 5 days a week for 8 weeks. Rats in the CD and HD groups were fed without swimming training. At the end of the exercise, all the rats were sacrificed and the blood, thoracic aorta and myocardium were collected immediately. The thoracic aortic vasoreactivity, the plasma total cholesterol (TC), triglyceride (TG), high-density lipoprotein (HDL), low-density lipoprotein (LDL), superoxide dismutase (SOD), malondialdehyde (MDA) and vascular endothelial nitric oxide synthase (eNOS) gene expression were measured. Compared to the control group, in the HD group the enhanced contractile response of the thoracic aortic rings to noradrenaline (NA) was observed (P

A bacterial strain, AN3, which was able to use aniline or acetanilide as sole carbon, nitrogen and energy sources was isolated from activated sludge and identified as Delftiasp. AN3. This strain was capable of growing on concentrations of aniline up to 53.8 mM (5000 mg/l). Substituted anilines such as N-methylaniline, N, N-dimethylaniline, 2-methylaniline, 4-methylaniline, 2-chloroaniline, 3-chloroaniline, o-aminoaniline, m-aminoaniline, p-aminoaniline, and sulfanilic acid did not support the growth of strain AN3. The optimal temperature and pH for growth and degradation of aniline were 30 degrees C and 7.0, respectively. The activities of aniline dioxygenase, catechol 2,3-dioxygenase and other enzymes involved in aniline degradation were determined, and results indicated that all of them were inducible. The K (m) and V (max) of aniline dioxygenase were 0.29 mM and 0.043 mmol/mg protein/min, respectively. The K (m) and V (max) of catechol 2, 3-dioxygenase for catechol were 0.016 mM and 0.015 mmol/mg protein/min, respectively. Based on the results obtained, a pathway for the degradation of aniline by Delftiasp. AN3 was proposed. The importance of the strain to the operation of municipal wastewater treatment plants is discussed.

In vitro, a new protocol of plant regeneration in rose was achieved via protocorm-like bodies (PLBs) induced from the root-like organs named rhizoids that developed from leaf explants. The development of rhizoids is a critical stage for efficient regeneration, which is triggered by exogenous auxin. However, the role of cytokinin in the control of organogenesis in rose is as yet uncharacterized. The aim of this study was to elucidate the molecular mechanism of cytokinin-modulated rhizoid formation in Rosa canina. Here, we found that cytokinin is a key regulator in the formation of rhizoids. Treatment with cytokinin reduced callus activity and significantly inhibited rhizoid formation in Rosa canina. We further isolated the full-length cDNA of a type-A response regulator gene of cytokinin signaling, RcRR1, from which the deduced amino acid sequence contained the conserved DDK motif. Gene expression analysis revealed that RcRR1 was differentially expressed during rhizoid formation and its expression level was rapidly up-regulated by cytokinin. In addition, the functionality of RcRR1 was tested in Arabidopsis. RcRR1 was found to be localized to the nucleus in GFP-RcRR1 transgenic plants and overexpression of RcRR1 resulted in increased primary root length and lateral root density. More importantly, RcRR1 overexpression transgenic plants also showed reduced sensitivity to cytokinin during root growth; auxin distribution and the expression of auxin efflux carriers PIN genes were altered in RcRR1 overexpression plants. Taken together, these results demonstrate that RcRR1 is a functional type-A response regulator which is involved in cytokinin-regulated rhizoid formation in Rosa canina.

The composite antibacterial agents were prepared with nano-hydroxyapatite containing polyvinyl alcohol, copper ions and zinc ions via the parcels and ion exchange respectively. The as-prepared antibacterial agents were characterized by X-ray diffraction, infrared spectrogram and scanning electron microscopy. The results show that PVA has been wrapped in the surface of hydroxyapatite, and copper and zinc ions had entered the structure of hydroxyapatite. The diameters of the antibacterial ring of Escherichia coli, Candida albicans, Bacillus subtilis and Staphylococcus aureus could be up to 18.32 mm, 14.09mm, 16.17mm and 21.05 mm respectively, which reveal that the composites possess excellent and a broad-spectrum antibacterial property.

A novel bacterial species, Rhodocista pekingensis sp. nov., was isolated from a municipal wastewater treatment plant and characterized by polyphasic taxonomy. Cells of R. pekingensis were gram-negative, motile by a single polar flagellum, vibrioid to spiral, 0.6-0.8 microm in width and 0.8-1.5 microm in length. R-bodies were not observed. Phototrophically grown cells contained lamellar photosynthetic membranes and bacteriochlorophyll a. Cell growth was anaerobically phototrophic or aerobically chemoheterotrophic. Anaerobically grown cultures were pink-reddish. Thiamin and vitamin B12, but not biotin, were required for growth and 0.05% yeast extract stimulated growth. Acetate, lactate, pyruvate and succinate supported growth. Cysts were formed when butyrate was used as the sole carbon source. Molecular hydrogen (H2), but not sulfide or thiosulfate, was used as an electron donor. The major cellular quinone was Q-9. The DNA G + C content of cells was 68.8 mol%. The type strain of Rhodocista pekingensis is 3-pT (=AS 1.2194T=JCM 11689T).