Search

Supercapacitor-like Na-ion batteries have attracted much attention due to the high energy density of batteries and power density of capacitors. Titanium dioxide (TiO2), is a promising anode material. Its performance is however seriously hindered by its low electrical conductivity and the sluggish diffusion of sodium ions (Na+) in the TiO2 matrix. Herein, this work combines porous TiO2 nanocubes with carbon nanotubes (CNTs) to enhance the electrical conductivity and accelerate Na+ diffusivity for Na-ion batteries (NIBs). In this composite, an interwoven scaffolded TiO2/CNTs framework is formed to provide abundant channels and shorter diffusion pathways for electrons and ions. The in-situ X-ray diffraction and cyclic voltammetry confirm the low strain and superior transport kinetics in Na+ intercalation/extraction processes. In addition, the chemically bonded TiO2/CNTs hybrid provides a more feasible channel for Na+ insertion/extraction with a much lower energy barrier. Consequently, the TiO2/CNTs composite exhibits excellent electrochemical performance with a capacity of 223.4 mAh g−1 at 1 C and a capacity of 142.8 mAh g−1 at 10 C (3.35 A g−1). The work here reveals that the combination of active materials with CNTs can largely improve the utilization efficiency and enhance their sodium storage.

Plant growth and development are regulated by phytohormones, such as abscisic acid, auxins, or gibberellins. Under drought stress, melatonin and the signaling calcium (Ca2+) are involved in plant defense and stress responses by controlling phytohormone and antioxidant machineries. Exogenous melatonin (MT) promotes drought stress tolerance in plants. As an essential second messenger, the signaling molecule Ca2+ is necessary in the stress tolerance of plants and might increase stress tolerance induced by exogenous melatonin. The present study elucidated the effects of Ca2+-MT on Dalbergia odorifera seedlings under drought stress. Results showed increases in growth traits and photosynthesis indexes (pigments, net photosynthetic rate, water use efficiency, stomatal conductance, and transpiration) by MT and Ca2+ under non stress and stress conditions. Under drought stress, the water status in leaves was slightly ameliorated by MT and Ca2+ treatments, whereas the Ca2+-MT combination strongly improved water status. Comparison between combined Ca2+-MT and single Ca2+/MT treatments showed that superoxide anion was significantly lower in Ca2+-MT-treated seedlings. Lipid peroxidation was lower in Ca2+-MT-treated seedlings under drought stress. Further, relative conductivity was significantly decreased by Ca2+ and MT treatments under stress compared with seedlings untreated with Ca2+ or MT under drought. The accumulation of proline decreased by Ca2+ and MT under stress, but the carbohydrates and protein contents were increased by exogenous MT and Ca2+. Under drought, antioxidant systems (peroxidase, superoxide dismutase, and catalase activities, and glutathione [GSH] and ascorbic acid [ASA] levels) were significantly increased by the Ca2+ and MT treatments. The combined treatment showed better performance in increasing GSH and ASA levels than single MT or Ca2+ treatment. The gibberellin GA3 and cytokine ZR increased significantly under non stress and stress conditions, but exogenous Ca2+ or MT did not increase their activities compared with those in the control groups. Exogenous Ca2+ and Ca2+-MT enhanced indole-3-acetic acid (IAA) content in D. odorifera leaves under stress compared with the control. Moreover, abscisic acid (ABA) level is downregulated by MT and Ca2+-MT treatments compared with the control. The seedlings treated with Ca2+ only showed increase in ABA concentration under drought stress. This study provides an insight into a possible coordination between Ca2+ and melatonin and into drought tolerance in woody plants.

Herein we develop a novel and effective alkoxide hydrolysis approach to in-situ construct the trimanganese tetraoxide (Mn3O4)/graphene nanostructured composite as high-performance anode material for lithium-ion batteries (LIBs). This is the first report on the synthesis of Mn3O4/graphene composite via a facile hydrolysis of the manganese alkoxide (Mn-alkoxide)/graphene precursor. Before hydrolysis, two dimensional (2D) Mn-alkoxide nanoplates are closely adhered to 2D graphene nanosheets via Mn-O chemical bonding. After hydrolysis, the Mn-alkoxide in-situ converts to Mn3O4, while the Mn-O bond is preserved. This leads to a robust Mn3O4/graphene hybrid architecture with 15 nm Mn3O4 nanocrystals homogeneously anchoring on graphene nanosheets. This not only prevents the Mn3O4 nanocrystals agglomeration but also inversely mitigates the graphene nanosheets restacking. Moreover, the flexible and conductive graphene nanosheets can accommodate the volume change. This maintains the structural and electrical integrity of the Mn3O4/graphene electrode during the cycling process. As a result, the Mn3O4/graphene composite displays superior lithium storage performance with high reversible capacity (741 mAh g−1 at 100 mA g−1), excellent rate capability (403 mAh g−1 at 1000 mA g−1) and long cycle life (527 mAg g−1 after 300 cycles at 500 mA g−1). The electrochemical performance highlights the importance of rational design nanocrystals anchoring on graphene nanosheets for high-performance LIBs application.

We report the well-designed active {1 1 0} and {1 1 1} faceted Cu2O hollow nanospheres (Cu2O-HNs) for the quick removal of the high concentration pollutants in water. For the first time, these Cu2O-HNs combine the advantages of the active facets, hollow structure and nanostructures. The abundance of dangling Cu atoms in two active facets results in positively charged surface to effectively react with the negatively charged pollutants. The hollow structure provides the opportunity to take full use of these active sites. Consequently, the active faceted Cu2O-HNs demonstrate excellent adsorption and photodegradation capacities for high concentrated anionic dyes. The smallest Cu2O-HNs (~100 nm) can adsorb ~90% of methyl blue (MB) (100 mg L−1) in 10 min and degrade ~92% of MB (100 mg L−1) in 10 min under visible-light. In particular, a film consisting of the smallest Cu2O-HNs can quickly remove high concentrated organic dyes and be reused after solar light irradiation for 10 min in air, showing the promising practical application for the removal of organic pollutants.

Objectives Osteoarthritis (OA) is a common degenerative joint disease with the pathological features of the reduced cartilage cellularity. Celastrol, a compound from Tripterygium wilfordii, exerted therapeutic effects on arthritis, but the potential mechanism remains unclear. Methods Tunicamycin was used to establish a model of OA in vitro, and ACLT surgery model in rats was applied to verify the mechanism. Chondrocytes were isolated from the knee articular cartilage of rabbit. MTT and flow cytometry assay were used to detect cell viability and apoptosis rate. Haematoxylin–eosin staining was used to assess for the histopathological changes. The activity and expression of apoptosis-related factors and ERs (endoplasmic reticulum stress)-related factors were detected by ELISA, WB, PCR and IHC, respectively. Key findings Celastrol exhibited significant enhancement on cell viability and reduced the rate of apoptosis in Tm-exposed chondrocytes. Celastrol reduced enzyme activity and protein expression of caspase-3, caspase-6 and caspase-9, decreased Bip, Atf6, Chop and Xbp-1 expression both at protein and mRNA levels. Celastrol showed a more significant effect on cell apoptosis rate and mRNA expression in the combination with 4-PBA. Conclusions This study reveals that celastrol may prevent OA by inhibiting the ERs-mediated apoptosis. All these might supply beneficial hints for celastrol on OA treatment.

Lithium-sulfur batteries with high theoretical specific capacity are quite promising in energy storage systems. The application of lithium-sulfur batteries however has mainly been hampered by the severe shuttle effect of polysulfides during the charging/discharging process. Here, we report the in situ self-assembling of ultra-thin flexible polyaniline layer decorated manganese dioxide nanoparticles (PANI-MnO2) to form a three-dimensional hierarchically porous network as a sulfur host for lithium-sulfur batteries. The hierarchically porous PANI-MnO2 network not only provides a porous structure to alleviate the volume expansion, but also offers fast channels to accelerate the transfer of active species, electrons and ions to improve the redox reaction kinetics. The as-fabricated PANI-MnO2-S electrode thus demonstrates excellent electrochemical performance, with a stable capacity up to 1195 mA h g-1 at 0.5C after 100 cycles. In particular, the hierarchically porous PANI-MnO2 network employs an extraordinary chemical process for polysulfides to form active thiosulfates, which are further converted into Li2S. This significantly suppresses the shuttle effect, thus providing the possibility for fast charging. As a result, the PANI-MnO2-S electrode exhibits a discharge capacity of 640 mA h g-1 at 2C after 500 cycles. Even at a high sulfur loading of 4.0 mg cm-2, a stable areal capacity of ∼3.12 mA h cm-2 is achieved at 1C after 200 cycles.

Metabolic engineering in plant can be describe as a tool using molecular biological technologies which promotes enzymatic reactions that can enhance the biosynthesis of existing compounds such as glycine betaine (GB) in plant species that are able to accumulate GB, or produce news compounds like GB in non-accumulators plants. Moreover we can include to these definition, the mediation in the degradation of diverse compounds in plant organism. For decades, one of the most popular ideas in metabolic engineering literature is the idea that the improvement of gly betaine or melatonin accumulation in plant under environmental stress can be the main window to ameliorate stress tolerance in diverse plant species. A challenging problem in this domain is the integration of different molecular technologies like transgenesis, enzyme kinetics, promoter analysis, biochemistry and genetics, protein sorting, cloning or comparative physiology to reach that objective. A large number of approaches have been developed over the last few decades in metabolic engineering to overcome this problem. Therefore, we examine some previous work and propose some understanding about the use of metabolic engineering in plant stress tolerance. Moreover, this chapter will focus on melatonin (Hormone) and gly betaine (Osmolyte) biosynthesis pathways in engineering stress resistance.

Photocatalytic hydrogen (H 2 )production based on semiconductors is important to utilize solar light for clean energy and environment. Herein, we report a visible light responsive heterostructure, designed and constructed by molybdenum disulfide quantum dots (MoS 2 -QDs)in-situ seeds-directing growth and self-assemble of zinc indium sulfide (ZnIn 2 S 4 )nanosheet to ensure their full contact through a simple one-step solvothermal method for highly improved visible light H 2 production. The MoS 2 -QDs in-situ seeds-directing ZnIn 2 S 4 heterostructure not only builds heterojunctions between MoS 2 and ZnIn 2 S 4 to spatially separate the photogenerated electrons and holes, but also serves as the active sites trapping photogenerated electrons to facilitate H 2 evolution. As a result, MoS 2 -QDs/ZnIn 2 S 4 exhibits high photocatalytic activity for H 2 production, and the optimized 2 wt% MoS 2 -QDs/ZnIn 2 S 4 (2MoS 2 -QDs/ZnIn 2 S 4 )heterostructure exhibits the highest H 2 evolution rate of 7152 umol·h −1 ·g −1 under visible light, ∼9 times of pure ZnIn 2 S 4 . Our strategy here could shed some lights on developing noble-metal free heterostructures for highly efficient photocatalytic H 2 production.

Aminopeptidase N (APN) belongs to the aminopeptidase family, which is widely distributed throughout the animal and plant kingdoms. APN is thought to be a very important target for cancer therapy as it is linked to cancer progression and metastasis. However, bestatin (Ubenimex) is the only approved drug that targets various aminopeptidases for the treatment of acute myelocytic leukemia and lymphedema. A compound 3-amino-2-hydroxy-4-phenylbutanoylvalylisoleucine (also known as LYRM03), isolated from a Streptomyces strain HCCB10043, exhibited more potent inhibitory activity than bestatin. In this work, we applied a chemical synthesis strategy to generate LYRM03 to overcome the low yields typically achieved from fermentation. Finally, we explored a suite of experiments to determine the bioactivity of LYRM03 and revealed that the metastasis of MDA-MB-231 cells was significantly restrained with LYRM03 treatment or injection both in vitro and in vivo. Because of its anti-metastasis capacity, further structure modifications of LYRM03 will be of interest for its use alone or in combination as a therapy in cancer.

BACKGROUND Studies have shown inconsistent associations of nitrite and nitrate intake with the risk of gastric cancer or its associated mortality. We performed a meta-analysis of observational studies to evaluate the correlation of nitrite and nitrate intake with the risk of gastric cancer. MATERIAL AND METHODS We searched for studies reporting effect estimates and 95% confidence intervals (CIs) of gastric cancer in PubMed, EMBASE, and the Cochrane Library through November 2018. The summary results of the included studies were pooled using a random-effects model. RESULTS Eighteen case-control and 6 prospective cohort studies recruiting 800 321 participants were included in this study. The summary results indicated that the highest (odds ratio [OR], 1.27; 95%CI, 1.03-1.55; P=0.022) or moderate (OR: 1.12; 95%CI, 1.01-1.26; P=0.037) nitrite intake were associated with a higher risk of gastric cancer. However, we noted that high (OR, 0.81; 95%CI, 0.68-0.97; P=0.021) or moderate (OR, 0.86; 95%CI, 0.75-0.99; P=0.036) nitrate intakes were associated with a reduced risk of gastric cancer. These associations differed when stratified by publication year, study design, country, the percentage of male participants, assessment of exposure, adjusted model, and study quality. CONCLUSIONS High or moderate nitrite intake was associated with higher risk of gastric cancer, whereas high or moderate nitrate intake was correlated with lower risk of gastric cancer.

Salinity is one of the most serious factors limiting plant growth which can provoke significant losses in agricultural crop production, particularly in arid and semi-arid areas. This study aimed to investigate whether melatonin (MT; 0.05 and 0.1 mM), which has pleiotropic roles, has a better effect than glycine betaine (GB; 10 and 50 mM) on providing salt tolerance in a woody plant Dalbergia odorifera T. Chen. Also, the alternative oxidase activity (AOX) in plant subjected to MT or GB under salinity (150 and 250 mM) was evaluated given that the effect of exogenous MT or GB on AOX has not been reported yet. The results showed that the exogenous application of GB on the seedlings of D. odorifera increased the plant growth parameters, relative water content, total of chlorophyll content, and carotenoid content compared with well-watered and MT treatments. Under severe salinity, the seedlings subjected to GB showed, a significant enhancement in water use efficiency, transpiration, and net photosynthetic rate regardless to MT-treated seedlings. The levels of proline and soluble sugar in the seedlings treated with MT or GB decreased significantly under mild and severe salinity correlated with those in salt-stressed seedlings. Furthermore, GB-treated plants exhibited a significant inhibition of malondialdehyde content compared with MT-treated plants. The concentration of thiols and phenolic compounds were significantly enhanced in the leaves of seedlings treated with MT compared with those treated with GB. Under salt stress condition, GB scavenged significantly higher levels of hydrogen peroxide than MT; while under severe salinity, plants subjected to MT showed better scavenging ability for hydroxyl radicals compared with GB-treated seedlings. The results demonstrated also an enhancement of the levels of superoxide dismutase (SOD), guaiacol peroxidase, and AOX activities in seedlings treated with GB or MT compared with salt-stressed plants. The catalase activity (CAT) was increased by 0.05 mM MT and 0.1 mM GB under mild salinity. Meanwhile, the AOX activity under severe salinity was enhanced only by GB 50 mM. The findings of this study suggested that GB-treated seedlings possessed a better salt tolerance in comparison with MT-treated seedlings.

Ni-based catalysts with different supports were prepared and characterized by N 2 physisorption, XRD, H 2 -TPR, H 2 chemisorption, and so on; the effect of support on the performance of Ni-based catalyst in methane dry reforming was then investigated. The results indicated that the support has a significant influence on the state of NiO species. SiO 2 , TiO 2 and ZrO 2 as a support have a weak interaction with NiO, which facilitates the reduction of the corresponding catalysts; however, the weak interaction may also lead to quick deactivation due to the agglomeration of active metal species. Al 2 O 3 and MgO have a strong interaction with NiO, which may promote the formation of NiAl 2 O 4 spinel and NiO-MgO solid solution, respectively, and make the reduction of corresponding catalysts very difficult. Al 2 O 3 modified by MgO is provided with both proper textural properties and interaction strength between metal and support, which are in favor of the dispersion and stabilization of NiO species. As a result, NiO supported on MgO-modified Al 2 O 3 exhibits superior catalytic performance in methane dry reforming even under very high gas hourly space velocity; it is quite stable during a long term test of more than 100 h.

Graphitic carbon nitride (g-C3N4) is a visible light active semiconductor. However, low conductivity and high recombination rate of photogenerated electrons and holes limit its application in photocatalysis. In this work, we design and synthesize hierarchically porous zinc oxide/graphitic carbon nitride (ZnO/g-C3N4) microspheres with type-II heterojunction to effectively degrade rhodamine B (RhB) via increasing the charge-separation efficiency. The ultraviolet-visible (UV–Vis) absorption spectra, Mott-Schottky plots and valence band X-ray photoelectron spectroscope confirm the formation of type-II heterojunction between ZnO nanocrystals and g-C3N4 nanosheets. As a result, the 1.5-ZnO/g-C3N4 composite (the mass ratio of zinc acetate dihydrate to g-C3N4 is 1.5) exhibits the highest photocatalytic activity with good stability and higher photocatalytic degradation rate comparing to pure g-C3N4 and pure ZnO. In addition, our results confirm that [rad]O2 − and h+ are the main active species for ZnO/g-C3N4 in degradation of RhB.

Doxorubicin is the mainstay of treatment for various haematological malignancies and solid tumours. However, its clinical application may be hampered by dose-dependent cardiotoxicity. The mechanism of doxorubicin-induced cardiotoxicity may involve various signalling pathways including free radical generation, peroxynitrite formation, calcium overloading, mitochondrial dysfunction and alteration in apoptosis and autophagy. Interestingly, the use of resveratrol in combination with doxorubicin has been reported to prevent cardiac toxicity as well as to exert a synergistic effect against tumour cells both in vivo and in vitro. Thus, the aim of this review is to summarize current knowledge and to elucidate the protective effect of resveratrol in doxorubicin-induced cardiotoxicity.

Thermoresponsive, particle-loaded, Poloxamer 407 (P407)-Pluronic-R® (25R4) or chitosan-methyl cellulose (MC) formulations were developed as single-dose, sustained release vaccines. The sol-gels, loaded either with a particulate vaccine (cubosomes) or soluble antigen (ovalbumin) and adjuvants (Quil A and monophosphoryl lipid A), were free-flowing liquids at room temperature and formed stable gels at physiological temperatures. Rheological results showed that both systems meet the criteria of being thermoresponsive gels. The P407-25R4 sol-gels did not significantly sustain the release of antigen in vivo while the chitosan-MC sol-gels sustained the release of antigen up to at least 14 days after administration. The chitosan-MC sol-gels stimulated both cellular and humoral responses. The inclusion of cubosomes in the sol-gels did not provide a definitive beneficial effect. Further analysis of the formulations with small-angle X-ray scattering (SAXS) revealed that while cubosomes were stable in chitosan-MC gels they were not stable in P407-25R4 formulations. The reason for the mixed response to cubosome-loaded vehicles requires more investigation, however it appears that the cubosomes did not facilitate synchronous vaccine release and may in fact retard release, reducing efficacy in some cases. From these results, chitosan-MC sol-gels show potential as sustained release vaccine delivery systems, as compared to the P407-25R4 system that had a limited ability to sustain antigen release.

Reducing the level of sulfur content in fuel oils has long been desired for environmental reasons. Polyoxometalates (POMs) can act as catalysts to remove sulfur-containing heterocyclic compounds by the process of oxidative desulfurization under mild conditions. However, one key obstacle to the development of POM-based catalysts is the poor solubility of POMs in the overall nonpolar environment. We report a novel strategy for the introduction of catalytically active POMs into nonpolar reaction systems by encapsulating the inorganic catalyst within the pores of a metal–organic framework structure in which the organic ligands act as hydrophobic groups. The nanocrystalline catalysts, obtained rapidly and conveniently by both solution and mechanochemical synthesis, showed remarkable activities in catalytic oxidative desulfurization reactions in both a model diesel environment and in real diesel wherein dibenzothiophene was converted rapidly and quantitatively into dibenzothiophene sulfone.

Purpose Directly returning straw back to the paddy field would significantly accelerate methane (CH4) emission, although it may conserve and sustain soil productivity. The application of biochar (biomass-derived charcoal) in soil has been proposed as a sustainable technology to reduce methane (CH4) emission and increase crop yield. We compared the effects of either biochar or rice straw addition with a paddy field on CH4 emission and rice yield.

Titanium dioxide (TiO2) nanoparticles have been widely used in many fields, including biomedicine, cosmetics and environmental engineering. Recently, it was reported that TiO2 nanoparticles could exert genotoxicity on organisms via the generation of reactive oxygen species (ROS). In the present study, we investigated the effect of TiO2 nanoparticles on RGC-5 cells with or without ultraviolet (UV) B irradiation through MTT assay and determination of hydroxyl radical production. The results demonstrated that TiO2 nanoparticles could efficiently inhibit the growth of RGC-5 cells in the presence of UVB irradiation, whereas there was little impact on target cells in the absence of UV irradiation; UV irradiation could apparently increase the level of hydroxyl radicals in RGC-5 cells and further efficiently inhibit the growth of RGC-5 cells, suggesting that UV irradiation plays an important role in growth inhibition in RGC-5 cells exposed to TiO2 nanoparticles.

Elevated global temperatures and increased concentrations of carbon dioxide (CO2) in the atmosphere associated with climate change will exert profound effects on rice cropping systems, particularly on their greenhouse gas emitting potential. Incorporating biochar into paddy soil has been shown previously to reduce methane (CH4) emission from paddy rice under ambient temperature and CO2. We examined the ability of rice straw-derived biochar to reduce CH4 emission from paddy soil under elevated temperature and CO2 concentrations expected in the future. Adding biochar to paddy soil reduced CH4 emission under ambient conditions and significantly reduced emissions by 39.5% (ranging from 185.4 mg kg−1 dry weight soil, dws season−1 to 112.2 mg kg−1 dws season−1) under simultaneously elevated temperature and CO2. Reduced CH4 release was mainly attributable to the decreased activity of methanogens along with the increased CH4 oxidation activity and pmoA gene abundance of methanotrophs. Our findings highlight the valuable services of biochar amendment for CH4 control from paddy soil in a future that will be shaped by climate change.

The expression of cystic fibrosis transmembrane conductance regulator (CFTR) in lymphocytes has been reported for nearly two decades; however, its physiological role remains elusive. Here, we report that co-culture of lymphocytes with lung epithelial cell line, Calu-3, promotes epithelial HCO(3)- production/secretion with up-regulated expression of carbonic anhydrase 2 and 4 (CA-2, CA-4) and enhanced bacterial killing capability. The lymphocyte-enhanced epithelial HCO(3)- secretion and bacterial killing activity was abolished when Calu3 cells were co-cultured with lymphocytes from CFTR knockout mice, or significantly reduced by interfering with E-cadherin, a putative binding partner of CFTR. Bacterial lipopolysaccharide (LPS)-induced E-cadherin and CA-4 expression in the challenged lung was also found to be impaired in CFTR knockout mice compared to that of the wild-type. These results suggest that the interaction between lymphocytes and epithelial cells may induce a previously unsuspected innate host defense mechanism against bacterial infection by stimulating epithelial HCO(3)- production/secretion, which requires CFTR expression in lymphocytes.

A Keggin-type polyoxometalate [SiW12O40]4− supported transition metal complex, {[Cu(py)2]4[SiW12O40]} (py = pyridine), has been synthesized by hydrothermal decarboxylation and characterized by elemental analyses, IR spectra, thermal stability analyses, and single-crystal X-ray diffraction. The compound is a 1-D chain containing an inorganic–organic backbone with alternating [SiW12O40]4− clusters and [Cu(py)2]+ along the c-axis, and with both three- and four-coordinate copper. The luminescence properties indicated that the emission peak is emission of pyridine, assigned to the Cu(I) to pyridine charge transfer. This air-stable Cu(I) complex can efficiently catalyze the O-arylation of both phenols and aryl halides.

The strategy for obtaining a crystalline catalyst based on a porous copper-based metal-organic framework and 12-tungstosilicic acid with different particle sizes is reported. Through the control of hydrothermal synthesis and some simple treatments, catalyst samples with average particle diameters of 23, 105, and 450 μm, respectively, were prepared. This crystal catalyst has both the Bronsted acidity of 12-tungstosilicic acid and the Lewis acidity of the copper-based metal-organic framework, and has high density of accessible acid sites. Its catalytic activity was fully assessed in the dehydration of methanol to dimethyl ether. The effect of particle size on the catalytic activity of catalyst was studied, in order to select the particle size appropriate for avoiding the diffusion limitation in heterogeneous gas-phase catalysis. In the selective dehydration of methanol to dimethyl ether, this catalyst exhibited higher catalytic activity than the copper-based metal-organic framework, γ-alumina, and γ-alumina-supported 12-tungstosilicic acid catalysts. It showed high catalytic performances, even at higher space velocity or in the presence of excess water. In addition, the catalyst was also preliminarily assessed in the formation of ethyl acetate from acetic acid and ethylene. It also exhibited a high activity which was comparable with that of silica-supported 12-tungstosilicic acid catalyst.

The reactivity of polyoxoniobates has been studied in acidic solution by grafting niobium onto trivacant Keggin-type germanotungstates. Four niobium-containing compounds were obtained in the course of this study. Cs 6.5 K 0.5 [GeW 9 (NbO 2 ) 3 O 37 ]·6H 2 O (Cs 6.5 K 0.5 -1) synthesized by the reaction of K 7 H[Nb 6 O 19 ] and A-α-Na 10 -[GeW 9 0 34 ] in H 2 O 2 solution is a tris-(peroxoniobium)-substituted A-α-GeW 9 derivative. Cs 6.5 K 0.5 [GeW 9 Nb 3 O 40 ]· 10H 2 O (Cs 6.5 K 0.5 -2) is a peroxo-free compound obtained by eliminating the peroxo groups in 1. Monomers 1 and 2 as precursors can each afford two nanoscale POMs, dimer Cs 5 [H 15 Ge 2 W 18 Nb 8 O 88 ]·18H 2 O (Cs 5 -3) and tetramer Cs 8 K 3 H 9 [Ge 4 W 36 Nb 16 O 166 ]· 27H 2 O (Cs 8 K 3 H 9 -4), through the formation of Nb—O—Nb bridges. Disassembly through the cleavage of Nb— O—Nb bonds from 4 to 2 and 1 was achieved by controlling the pH and by adding H 2 O 2 , respectively. The transition from 1 to 2 can be achieved by simply adding H 2 O 2 to a solution of 1. All four compounds were characterized in the solid state by elemental analysis, infrared spectroscopy, thermogravimetry, and single-crystal X-ray diffraction. 183 W NMR analysis proved that the solid-state structures of polyanions 1-4 were retained after dissolution. Disassembly from 4 to 1 and 2 in solution was observed by 183 W NMR spectroscopy. The UV/Vis spectra of 1 at different pH confirmed that it is stable in the pH range of 0.1-14.0 at room temperature.

In this study, we have fabricated the functionalized nickel nanoparticles and investigated their effects on cellular uptake of quercetin in leukemia K562 cancer cells by using electrochemical assay. The results indicate that nickel nanoparticles could efficiently enhance the quercetin uptake and increase the intracellular accumulation in cancer cells, implying the great potential of functionalized nickel nanoparticles in target cancer therapy.

In order to explore the possible physiological mechanism of high temperature induced sterility in rice, we examined the floret sterility and endogenous plant growth regulator contents in pollens of two hybrid rice cultivars Shanyou63 and Teyou559 that are tolerant and susceptible to high temperature, respectively. Indexes of floret sterility, pollen activity, and variation of endogenous indole-3-acetic acid (IAA), gibberellic acids (GAs), abscisic acid (ABA), free proline and soluble proteins in anthers were measured. We found that during the course of high temperature treatment, both cultivars exhibited a marked decrease in pollen activity, pollen germination and floret fertility; however, the high temperature tolerant Shanyou63 showed a much slower rate of decrease than the high temperature susceptible Teyou559. In addition, anthers of both cultivars displayed a decrease in the contents of IAA, GAs, free proline and soluble proteins but an increase in the ABA content. Yet compared to Teyou559, Shanyou63 retained significantly higher levels of free praline and GAs and a lower level of ABA, along with higher pollen vigour and pollen germination rate even after prolonged high temperature treatment. Our study suggests a possible correlation between pollen viability/floret sterility and high temperature-caused changes in IAA, GAs, ABA, free proline and soluble protein contents. The severity in these changes may reflect the variation of rice cultivars in their heat stress sensitivities for floret development.

Resveratrol (RSV) has many biological effects, including antitumor and antiviral activities, and vascular protection. Recent studies have suggested that RSV exerts its antitumor effects through induction of autophagy by an unknown mechanism. Doxorubicin (DOX) is a wide spectrum antitumor drug, but its clinical application is limited by its cardiotoxicity. This study evaluated whether the manipulation of autophagy could attenuate the cardiotoxic effects of DOX in vitro as well as in a rat model of DOX-induced cardiotoxicity. We found that DOX induced H9C2 cell apoptosis by inhibiting AMPK activation and promoting pro-apoptotic protein expression through p38MAPK/p53 signaling. RSV-treated H9C2 cells showed increased autophagy through the AMPK/mTOR/Ulk1 pathway. When DOX and RSV were combined, apoptosis was decreased, despite a slight increase in the autophagy ratio. The same result was observed in the rat model of DOX-induced cardiotoxicity. Injection with DOX or RSV alone, or in combination, for a week, resulted in a reduced apoptotic ratio in the combination group compared with the DOX alone group. Our results strongly indicate that this co-treatment strategy with RSV can attenuate the cardiotoxic effects of DOX. Our findings may have important clinical implications.

MicroRNAs are endogenous short chain nucleotide RNAs that regulate gene function by direct binding of target mRNAs. In this study, we investigated the effects of microRNA-206 (miR-206) on the development of gastric cancer. miR-206 was first confirmed to be downregulated in gastric cancer specimens. Conversely, upregulation of c-Met was confirmed in tissue samples of human gastric cancer, with its level inversely correlated with miR-206 expression. Introduction of miR-206 inhibited cellular proliferation by inducing G1 cell cycle arrest, as well as migration and invasion. Moreover, important proliferation and/or migration related molecules such as c-Met, CDK4, p-Rb, p-Akt and p-ERK were confirmed to be downregulated by Western blot analysis. Targeting of c-Met also directly affected AGS cell proliferation, migration and invasion. In vivo, miR-206 expressing tumor cells also displayed growth delay in comparison to unaffected tumor cells. Our results demonstrated that miR-206 suppressed c-Met expression in gastric cancer and could function as a potent tumor suppressor in c-Met overexpressing tumors. Inhibition of miR-206 function could contribute to aberrant cell proliferation and migration, leading to gastric cancer development.

Gallbladder cancer (GBC), although considered as a relatively rare malignancy, is the most common neoplasm of the biliary tract system. The late diagnosis and abysmal prognosis present challenges to treatment. The overall 5-year survival rate for metastatic GBC patients is extremely low. BRCA1 and BRCA2 are the breast cancer susceptibility genes and their mutation carriers are at a high risk for cancer development, both in men and women. Olaparib, an oral poly ADP-ribose polymerase inhibitor, has been approved by the Food and Drug Administration and the European Commission for the treatment of ovarian cancer with any BRCA1/2 mutations. The first case of a BRCA1-mutated GBC patient who responded to olaparib treatment is reported here.

The adsorption of nanostructured lyotropic liquid-crystal particles, cubosomes and hexosomes, at surfaces was investigated for potential use in surface-specific agrochemical delivery. Adsorption of phytantriol (PHYT) and glyceryl monooleate (GMO)-based cubosomes and hexosomes, stabilized using Pluronic F127, at tristearin-coated (model leaf surface) and uncoated zinc selenide surfaces was studied using attenuated total reflectance Fourier transform IR (ATR-FTIR) spectroscopy, by quantifying the IR absorbance due to the lipid components of the particles over time. The delivery of an encapsulated hydrophobic model herbicide [dichlorodiphenyldichloroethylene (DDE)] was also examined on the model and real leaf surfaces. The adsorption behavior of the particles by ATR-FTIR was dependent on the internal nanostructure and lipid composition, with PHYT cubosomes adsorbing more avidly at tristearin surfaces than GMO-based cubosomes or hexosomes. There was a direct correlation between DDE associated with the surfaces and the particle adsorption observed in the ATR-FTIR study, strongly implicating particle adsorption with the delivery efficiency. Differences between the mode of interaction of the Pluronic stabilizer with the different lipids and particle nanostructures were proposed to lead to differences in the particle adsorption behavior.

A sodalite-type porous metal-organic framework with polyoxometalate templates, H(3)[(Cu(4)Cl)(3)(BTC)(8)](2)[PW(12)O(40)]·(C(4)H(12)N)(6)·3H(2)O (NENU-11; BTC = 1,3,5-benzenetricarboxylate), was obtained by a hydrothermal reaction. As a reasonable candidate for eliminating nerve gas, NENU-11 displays good adsorption behavior for dimethyl methylphosphonate (15.5 molecules per formula unit). In virtue of the catalytic activity of polyoxometalate guests, this nerve gas mimic could be facilely decomposed by a hydrolysis reaction.

66-4 FIELD Section Title:Surface Chemistry and Colloids Research Institute of Petroleum Processing, SINOPEC, Beijing, Peop. Rep. China. FIELD URL: written in English; In this paper, a new delaminated mesoporous material was prepd. by swelling the lamellar phyllosilicate Magadiite using cetyltrimethylammonium bromide and tetrapropylammonium hydroxide soln., followed by delamination under the cavitation of ultrasonic treatment. Various characterization tools including XRD, N2 adsorption, NMR, IR, SEM and TEM were employed to observe its structure and morphol. XRD results show that the delaminated material has no long-range cryst. order. Furthermore, not only high surface area is obtained, but almost half of it is external surface. The observation for the morphol. further reveals that it is made up of the random stacking of single or few layers. All these characters show that this delaminated mesoporous material meets the requirements for application as support in the hydrotreatment of heavy mols. [on SciFinder(R)]

The reduction of CuO with different amount of carbon (CuO:C?=?2:1, 2:1.5, and 2:2, in molar ratio) induced by ball milling is examined by x-ray diffraction and transmission electron microscopy. It is found that reduction process is closely related to the carbon content. CuO can be completely converted into Cu if an excessive C is used (i.e., C?=?1.5 or 2.0 mol). However, the reduction of CuO follows a two-step process, CuO->Cu->Cu2O, if the mixture only contains a nominal C content (i.e., C?=?1 mol). A tentative model in terms of solid state reaction at the interfaces is proposed to explain the effect of carbon content on the mechanoreduction of CuO.

The Dawson anion P 2W 18O 62 (6-) has been used as a noncoordinating polyoxoanion template for the construction of two metal-organic frameworks, namely, [M 2(bpy) 3(H 2O) 2(ox)][P 2W 18O 62]2(H 2-bpy). nH 2O (M = Co(II), n = 3 ( 1); M = Ni(II), n = 2 ( 2)) (bpy = 4,4'-bipyridine; ox = C 2O 4 (2-)). Single-crystal X-ray analysis reveals that both of the structures exhibit 3D host frameworks constructed from the oxalate-bridged binuclear superoctahedron secondary building units (SBUs) and bpy linkers and the voids of which are occupied by Dawson anions, guest bpy, and water molecules. Magnetic studies reveal that there are antiferromagnetic exchange interactions among the transition-metal centers in compounds 1 and 2. Furthermore, a compound 1-modified carbon paste electrode ( 1-CPE) displays good electrocatalytic activity toward the reduction of nitrite.

Purpose Retinal pigment epithelial (RPE) cells play important roles in ophthalmologic diseases such as proliferative vitreoretinopathy, AMD, and diabetic retinopathy. MicroRNA-34a (miR-34a) has been reported to be important in the regulation of cell proliferation, migration, differentiation, and apoptosis. In this study, we explored the effects of miR-34a on RPE cells. Methods The expression level of miR-34a in subconfluent and postconfluent ARPE-19 cells was investigated with quantitative real-time PCR. MicroRNA mimic and small interfering RNA (siRNA) were transiently transfected into RPE cells. Transfected RPE cells were analyzed with WST-1 proliferation assay, and their migration was analyzed with transwell assay and in vitro scratch study. The expression or activation of target proteins was detected by Western blotting. Results MicroRNA-34a was significantly downregulated in subconfluent ARPE-19 cells compared with postconfluent cells. Introduction of miR-34a inhibited the proliferation and migratory ability of RPE cells without obvious cell apoptosis. In miR-34a transfected cells, many important proliferation and/or migration related molecules such as c-Met, CDK2, CDK4, CDK6, E2F1, and phosphorylated-Cdc2 (p-Cdc2) were downregulated. Small interfering RNA designed to target c-Met also inhibited the proliferation and migration of RPE cells and downregulated CDK2, CDK6, E2F1, and p-Cdc2. Conclusions MicroRNA-34a is downregulated in subconfluent RPE cells. MicroRNA-34a can inhibit the proliferation and migration of RPE cells through downregulation of its targets c-Met and other cell cycle-related molecules. Our results indicated that miR-34a is involved in the regulation of RPE cells.

A 9-connected, trinuclear cluster-based microporous metal–organic framework, Ni3(OH)(Ina)3(BDC)1.5 (Ina = isonicotinate and BDC = 1,4-benzenedicarboxylate) (1), was synthesized and characterized. The structure is constructed from a 3D channel and two kinds of cages (tetrahedron and triangular pyramid cages). Compound 1 is microporous with a BET surface area of 1255 m2 g−1. It has been observed that the amount of adsorbed benzene (22.60%) is much higher than that of cyclohexane (1.40%), showing its potential to separate benzene and cyclohexane.

PURPOSE: MicroRNAs (miRNAs) are endogenously expressed, noncoding, small RNAs that inhibit protein translation through binding to target mRNAs. Recent studies have demonstrated that miRNAs can regulate tumor cell proliferation and migration. MicroRNA-34a (miR-34a), a potential key effector of the p53 tumor-suppressor gene, was studied as a potential tumor suppressor in uveal melanoma. METHODS: Northern blot analysis was performed to detect the expression level of miR-34a in uveal melanoma cells and melanocytes. Subsequently, melanoma cell proliferation and migration were examined by MTS cell proliferation and transwell migration assays, respectively. The target of miR-34a was predicted by bioinformatics and confirmed using a luciferase assay. In addition, expression of c-Met and cell cycle-related proteins was determined by Western blotting and immunofluorescence after the introduction of miR-34a. RESULTS: miR-34a is actively expressed in melanocytes but not in uveal melanoma cells based on Northern blot analysis. Transfection of miR-34a into uveal melanoma cells led to a significant decrease in cell growth and migration. After identification of two putative miR-34a binding sites within the 3' UTR of the human c-Met mRNA, miR-34a was shown to suppress luciferase activity using HEK293 cells with a luciferase reporter construct containing the binding sites. miR-34a was confirmed to downregulate the expression of c-Met protein by Western blotting and immunofluorescence. Furthermore, the introduction of miR-34a downregulated phosphorylated Akt and cell cycle-related proteins. CONCLUSIONS: These results demonstrate that miR-34a acts as a tumor suppressor in uveal melanoma cell proliferation and migration through the downregulation of c-Met .