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Polymers of intrinsic microporosity (PIMs) have been the potential candidates as gas separation membrane materials, because of their high permeability and good processing. Here, three PIMs (PIM-ABA...

Electrically responsive electrochemical actuators that contain a polymer electrolyte membrane laminated between two electrodes have attracted great attention due to their potential applications in smart electronics, wearable devices, and soft robotics. However, some challenges such as the achievement of large bending strain under low applied voltage and fast ion diffusion and accumulation still exist to be resolved. The key to the solution lies in the choice of electrode materials and the design of electrode structures. In this study, an engineering electrochemical actuator that presents large bending strain under low applied voltage based on MXene/polystyrene-MXene hybrid electrodes is developed. The developed electrochemical actuator based on the MXene/polystyrene-MXene 3D-structure is found to exhibit large bending strain (ca. 1.18%), broad frequency bandwidth, good durability (90% retention after 10,000 cycles) and considerable Young’s modulus (ca. 246 MPa). The high-performance actuation mainly stems from the excellent properties of MXene and 3D-structure of the electrode. The MXene provides excellent mechanical strength and high electrical conductivity which facilitate strong interaction and rapid electron transfer in electrodes. The 3D architectures formed by polystyrene microspheres generate unimpeded ion pathways for ionic short diffusion and fast injection. This study reveals that the 3D-structure hybrid electrodes play a crucial role in promoting the performance of such electrochemical actuators.

Shape memory polymers (SMPs) that change shapes as designed by external stimuli have become one of the most promising materials as actuators, sensors, and deployable devices. However, their practical applications have been greatly limited due to the long recovery time, which mainly originates from their low recovery stress, inherent viscoelastic hysteresis effect and low heat transmission efficiency. In this work, a novel method is proposed to prepare fast responsive reduced graphene oxide/shape memory polyurethane/polyurethane foam (rGO/SMPU/PU foam) shape memory composites. The elastic PU foam is used as framework to be coated with SMPU and rGO by solution polymerization and self-assembly methods, which result in rGO/SMPU/PU foam with three-dimensional networks. The rGO/SMPU/PU foam exhibits a fast response (of less than 1 s) under a large compressing deformation (80%) due to the synergistic effect of the high elasticity of PU foam, the short energy transmission distance of the SMPU layer and the high thermal conductivity of the rGO layer. Moreover, owing to the outstanding shape fixity ratio (Rf) and shape recovery ratio (Rr) of SMPU and the mechanical properties of PU foam, the rGO/SMPU/PU foam shows an excellent shape memory effect (more than 98% Rf and Rr at 80% strain) and cyclic stability simultaneously. Such rGO/SMPU/PU foam material demonstrates the potential applications in high-sensitivity temperature sensors and temperature codes.

Linear polyimides of intrinsic microporosity have been intensively investigated for gas separation due to their microporous structure and high surface area. The microporous structure in the linear polyimides of intrinsic microporosity comes from their contorted structure. Therefore, most linear polyimides without contorted structure do not have micropores. In this work, the microporous polyimides are constructed through the condensation of a cross-linkable dianhydride monomer with two novel nitrogen-rich diamine monomers and post crosslinking reaction. The linear polyimide precursors without contorted structure have the same main-chain structure. The introduction of crosslinked structure endow the crosslinked polyimides (PI-CLs) with microporous structure. The microporous structure in PI-CLs can be tuned by changing the substituents of the linear polyimide precursors. The PI-CLs have competitive CO2 uptake capacity (7.3–9.4 wt%) at 273 K and 1 bar. Particularly, the crosslinked polyimide containing trifluoromethyl groups (CF3-PI-CL) shows high CO2/N2 and CO2/CH4 selectivity (72 and 22) at 273 K, which are among the best results for reported porous materials. This work reveals that the introduction of crosslinked structure and changing substituents is an efficient method for constructing microporous polyimides with abundant micropores and excellent CO2 selective adsorption capacity. This method also has great potential for fabricating high-performance microporous polymers based on other linear polymers without rigid contorted structure.

Porphyrin units are a kind of ideal electron donor units, which have large π conjugation and well-defined planar and electron-rich structures. The inserted alkynyl π bridges between porphyrin units...

This study investigated the removal efficiencies of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) and chlorobenzenes (CBzs) by different air pollution control devices (APCDs) in three municipal solid waste incinerators (MSWIs). These devices were the semi-dry flue gas desulfurization (SDFGD) system, activated carbon (AC) injector, bag filters (BF), selective catalytic reduction (SCR) reactor, and wet scrubber. The SDFGD system, AC injector, and BF exhibited similar removal efficiencies for all of the pollutants. Overall, the removal efficiency of CBzs was also considerably lower than the PCDD/Fs. The less chlorinated CBzs were also less likely to be adsorbed by AC and BF and more likely to be decomposed by the SCR reactor. Additionally, the “memory effect” in the wet scrubbers elevated the concentrations of the PCDD/Fs and even the CBzs in the flue gas, with the highest increases observed for penta- to hepta-chlorinated PCDD/Fs and TrCBzs. Given the different effects of these various devices, especially the wet scrubber, the correlation between PCDD/F and CBz removal should be individually assessed for each APCD unit. More accurate indicators of PCDD/F removal are also examined.

In order to reduce the overpotential of hydrogen evolution reaction (HER), the ternary coating Co-W-P was deposited on the surface of the nickel foam by electrochemical deposition to obtain a highly active electrode. Based on the measured double layer capacitance (Cdl) and HER activity, there is volcanic behavior between the intrinsic activity of Co-W-P and the Co:W ratio in the electrolyte. W and P play different roles in the formation of nanoparticles, and work together to achieve the large electrochemical surface area and excellent activity. When applied to the modification of other catalysts (Ni-P and Fe-P), the higher intrinsic activity was obtained after the introduction of W.

INTRODUCTION: Progression of pulmonary fibrosis, characterized by the deterioration of lung tissue’s mechanical properties, is affected by respiratory motion-induced dynamic loading. Since the development of anti-fibrosis drugs faces major hurdles in animal tests and human clinical trials, preclinical models that can recapitulate fibrosis progression under physiologically-relevant cyclic loading hold great promise. However, the integration of these two functions has not been achieved in existing models. METHODS: Recently we developed static human lung microtissue arrays that recapitulate the progressive changes in tissue mechanics during lung fibrogenesis. In the current study, we integrate the lung microtissue array with a membrane stretching system to enable dynamic loading to the microtissues. The effects of a pro-fibrotic agent and anti-fibrosis drugs were tested under cyclic stretching. RESULTS: Cyclic stretching that mimics respiratory motion was shown to affect the cytoskeletal organization and cellular orientation in the microtissue and cause the increase in microtissue contractility and stiffness. Fibrosis induction using TGF-β1 further promoted fibrosis-related mechanical activity of the lung microtissues. Using this system, we examined the therapeutic effects of two FDA approved anti-fibrotic drugs. Our results showed that Nintedanib was able to fully inhibit TGF-β1 induced force increase but only partially inhibited stretching induced force increase. In contrast, Pirfenidone was able to fully inhibit both TGF-β1 induced force increase and stretching-induced force increase. CONCLUSIONS: Together, these results highlight the pathophysiologically-relevant modeling capability of the current fibrotic microtissue system and demonstrated the potential of this system to be used for anti-fibrosis drug screening. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s12195-019-00590-3) contains supplementary material, which is available to authorized users.

Developing porous organic polymer materials with plenty micropores is of great importance for highly selective CO2 capture under ambient conditions. Here, to tune the pore size, two novel microporous hyperbranched polyimide networks, in which the distance between the polymer skeleton and crosslinking points is different, are successfully prepared by a two-step pathway combining polymerization and crosslinking reaction. It is intriguingly found that both porosity and CO2 sorption performance of microporous hyperbranched polyimides can be finely tuned by reducing the distance between the polymer skeleton and crosslinking points from PEPHQDA-HBPI-CL to PEQDA-HBPI-CL. The micropore size decrease from 1.18 nm to 0.86 nm, and CO2 adsorption capacity increase from 6.38 to 6.51 wt% (298 K and 1 bar). More excitingly, the PEQDA-HBPI-CL demonstrates the high CO2/N2 and CO2/CH4 selectivity up to 109 and 15 (273 K, 1 bar) according to the Henry's law, which are superior to those of many other microporous organic polymers and among the best results for porous inorganic/ organic materials. This work reveals that the shorter-distance between the polymer skeleton and crosslinking points is in favor of fabricating microporous hyperbranched polyimide networks with abundant smaller micropore and high CO2 selectivity, which are crucial importance for the CO2 capture and storage.

The high durability of low-k value is the key parameter for the low dielectric materials especially used under humid conditions, because the k value is very sensitive to moisture. Here, to decrease the dielectric constant and improve the water resistance, a series of novel co-polyimides are successfully prepared based on cross-linkable diamine monomer by a two-step pathway combining polymerization and crosslinking reaction. It is intriguingly found that with the gradual increase content of cross-linkable group, the dielectric properties, water resistance as well as thermal and mechanical properties of those co-polyimides can be finely tuned. After cross-linking, the dielectric properties are significantly enhanced and the film surface changed from hydrophilic (78.7–89.2°) to hydrophobic (93.0–104.2°), which endow the cross-linked films with superior water resistance and high durability of low-k value. The best performance is obtained for cross-linked co-polyimide (CL-Co-PI-4) containing 30% cross-linkable group. The CL-Co-PI-4 exhibits low dielectric constant of 2.32 and dielectric loss of 0.016 at 1 MHz. Excitingly, the CL-Co-PI-4 demonstrates an extremely low water uptake of 0.051 ± 0.010%, which represents the best water resistance for the reported polyimides. After exposing to different humidity conditions for 12 h, the increasing percentage of k value is very low and below 0.84%. The CL-Co-PI-4 still keep its k value below 2.35 after equilibrating at 75% R.H. for 14 days. The excellent moisture resistance and overall performance make the CL-Co-PI-4 a good candidate for dielectric material under both dry and humid conditions.

Microporous polyimides have been extensively investigated for gas capture and separation applications. Polyimides with intrinsic microporosity with contorted structures exhibit high surface areas. However, except for polyimides with intrinsic microporosity, most linear polyimides do not have microporous structures. Here, a crosslinked structure is introduced into linear polyimides to construct microporous polyimide networks with high surface areas. It is intriguingly found that the surface areas of the microporous polyimide networks increased by about ten times compared with the uncrosslinked polyimides; they are in the range of 635–727 m2 g−1 and among the best reported results for linear polyimides with intrinsic microporosity. TF-PI-CL and 6FA-PI-CL can respectively adsorb 10.03 and 7.28 wt% CO2 (273 K/1 bar). Meanwhile, the CO2/N2 and CO2/CH4 selectivities of TF-PI-CL are 58.4 and 12.9, respectively. This work reveals that the introduction of a crosslinked structure is an effective method of fabricating microporous polyimide networks with high surface area and highly selective CO2 capture capacity based on linear polyimides, which is crucial for CO2 capture and storage.

We report a reversible photo-induced doping effect in two-dimensional (2D) tungsten diselenide (WSe2) field effect transistors on hexagonal boron nitride (h-BN) substrates under low-intensity visible light illumination (∼10 nW μm-2). Our experimental results have shown that this reversible doping process is mainly attributed to two types of defects in h-BN substrates. Moreover, the photo-doped WSe2 transistors can be stable for more than one week in a dark environment and maintain the high on/off ratio (108) and carrier mobility, since there are no additional impurities involved during the photo-induced doping process to increase the columbic scattering in the conducting channel. These fundamental studies not only provide an accessible strategy to control the charge doping level and then to achieve a writing/erasing process in 2D transistors, but also shed light on the defect states and interfaces in 2D materials.

A novel heterogeneous catalyst, the ionic liquid (IL) of 1-butyl-3-methylimidazolium acetate (BmimOAc) immobilized on MIL-101-NH2, denoted as IL(OAc–)-MIL-101-NH2, was prepared by the “ship-in-a-bottle” strategy. The IL of BmimOAc was prepared in the MIL-101-NH2 nanocages primordially, in which the condensation product of MIL-101-NH2’s amine group with 1,1′-carbonyldiimidazole (CDI) reacted with 1-bromo butane, and then the intermediate exchanged with potassium acetate. The structure and physicochemical properties of IL(OAc–)-MIL-101-NH2 were characterized by powder X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, DRS UV–vis, nitrogen adsorption–desorption, and elemental analysis. The results indicated that BmimOAc was anchored in the MIL-101-NH2 skeleton via the acylamino group and confined in the nanocages in the form of a single molecule. The composite material of IL(OAc–)-MIL-101-NH2 exhibited excellent catalytic activity and catalytically synthesized 3-aryl-2-...

Jincai Wang,1 Xufeng Zhang,1 Fang Yang,2 Yuguang Yang,1 Tianjiao Wang,1 Wenming Liu,1 Hongfeng Zhou,1 Wei Zhao3 1Department of Medical Oncology, Harbin Medical University Cancer Hospital, Harbin, Heilongjiang 150086, People’s Republic of China; 2Department of Medical Oncology, Boao Evergrande International Hospital, Qionghai, Hainan 571400, People’s Republic of China; 3Department of Neurobiology, Harbin Medical University, Heilongjiang Provincial Key Laboratory of Neurobiology, Harbin, Heilongjiang, 150086, People’s Republic of ChinaCorrespondence: Wei ZhaoDepartment of Neurobiology, Harbin Medical University, Heilongjiang Provincial Key Laboratory of Neurobiology, No. 194, Harbin, Heilongjiang 150086, People’s Republic of ChinaTel +86-13796666580Email Zhaowei7700@126.comObjective: Cisplatin (DDP) is an effective first-line therapy for non-small cell lung cancer (NSCLC) treatment; however, it can cause resistance and thus pose an obstacle to the efficacy of chemotherapy in NSCLC. This study aims to detect the effect of RASSF1A on DDP resistance of NSCLC and the underlying mechanism.Methods: The expression levels of RASSF1A and microtubule-associated protein 1S (MAP1S) were investigated by qRT-PCR and Western blot and their interaction was testified by co-immunoprecipitation (Co-IP) analysis. The IC50 value of DDP on A549 and A549/DDP cells (DDP-resistant cells) was measured. A549/DDP cells were transfected with pCDNA3.1-RASSF1A, pCDNA3.1-MAP1S, or si-RASSF1A, followed by treated with DDP. Cell counting kit-8 (CCK-8) and 5-ethynyl-2ʹ-deoxyuridine (EDU) were employed to measure cell survival rate. Western blot was applied to test the levels of autophagy-associated proteins p62, LC3II, and LC3I. Immunofluorescence staining was used to detect the green fluorescent protein (GFP)-LC3 puncta to evaluate the level of autophagy. Finally, a xenograft model in nude mice using A549/DDP cells was developed.Results: RASSF1A and MAP1S were lowly expressed and positively correlated in NSCLC tissues. We observed that RASSF1A and MAP1S overexpression significantly enhanced DDP-induced effects in A549 and A549/DDP cells, including decreased cell viability, as well as increased autophagy levels. Besides, investigations into the mechanism between RASSF1A and MAP1S disclosed that RASSF1A could regulate MAP1S to inactivate the Keap1-Nrf2 pathway, thus activating autophagy to enhance chemosensitivity. Moreover, consistent results were confirmed in vivo experiments.Conclusion: RASSF1A increases chemosensitivity in NSCLC by facilitating autophagy via MAP1S-mediated Keap1-Nrf2 pathway.Keywords: RASSF1A, MAP1S, chemosensitivity, autophagy, Keap1-Nrf2, A549/DDP

Background The Zc3h8 gene encodes a protein with three zinc finger motifs in the C-terminal region. The protein has been identified as a component of the Little Elongation Complex, involved in transcription of small nuclear RNAs. ZC3H8 is overexpressed in a number of human and mouse breast cancer cell lines, and elevated mRNA levels are associated with a poorer prognosis for women with breast cancer. Methods We used RNA silencing to decrease levels of expression in mouse mammary tumor cells and overexpression of ZC3H8 in cells derived from the normal mouse mammary gland. We measured characteristics of cell behavior in vitro, including proliferation, migration, invasion, growth in soft agar, and spheroid growth. We assessed the ability of these cells to form tumors in syngeneic BALB/c mice. ZC3H8 protein was visualized in cells using confocal microscopy. Results Tumor cells with lower ZC3H8 expression exhibited decreased proliferation rates, slower migration, reduced ability to invade through a basement membrane, and decreased anchorage independent growth in vitro. Cells with lower ZC3H8 levels formed fewer and smaller tumors in animals. Overexpression of ZC3H8 in non-tumorigenic COMMA-D cells led to an opposite effect. ZC3H8 protein localized to both PML bodies and Cajal bodies within the nucleus. ZC3H8 has a casein kinase 2 (CK2) phosphorylation site near the N-terminus, and a CK2 inhibitor caused the numerous PML bodies and ZC3H8 to coalesce to a few larger bodies. Removal of the inhibitor restored PML bodies to their original state. A mutant ZC3H8 lacking the predicted CK2 phosphorylation site showed localization and numbers of ZC3H8/PML bodies similar to wild type. In contrast, a mutant constructed with a glutamic acid in place of the phosphorylatable threonine showed dramatically increased numbers of smaller nuclear foci. Conclusions These experiments demonstrate that Zc3h8 expression contributes to aggressive tumor cell behavior in vitro and in vivo. Our studies show that ZC3H8 integrity is key to maintenance of PML bodies. The work provides a link between the Little Elongation Complex, PML bodies, and the cancer cell phenotype. Electronic supplementary material The online version of this article (10.1186/s12885-018-4674-1) contains supplementary material, which is available to authorized users.

Aspirin can efficiently inhibit liver cancer growth, but the mechanism is poorly understood. In this study, we report that aspirin modulates glucose uptake through downregulating glucose transporter 1 (GLUT1), leading to the inhibition of hepatoma cell proliferation. Our data showed that aspirin significantly decreased the levels of reactive oxygen species (ROS) and glucose consumption in hepatoma cells. Interestingly, we identified that GLUT1 and HIF1α could be decreased by aspirin. Mechanically, we demonstrated that the -1008/-780 region was the regulatory element of transcriptional factor NF-κB in GLUT1 promoter by luciferase report gene assays. PDTC, an inhibitor of NF-κB, could suppress the expression of GLUT1 in HepG2 and H7402 cells, followed by affecting the levels of ROS and glucose consumption. CoCl(2)-activated HIF1α expression could slightly rescue the GLUT1 expression inhibited by aspirin or PDTC, suggesting that aspirin depressed GLUT1 through targeting NF-κB or NF-κB/HIF1α signaling. Moreover, we found that GLUT1 was highly expressed in clinical HCC tissues relating to their paired adjacent normal tissues. Importantly, we observed that high level of GLUT1 was significantly correlated with the poor relapse-free survival of HCC patients by analysis of public data. Functionally, overexpression of GLUT1 blocked the PDTC-induced or aspirin-induced inhibition of glucose metabolism in HepG2 cells. Conversely, aspirin failed to work when GLUT1 was stably knocked down in the cells. Administration of aspirin could depress the growth of hepatoma cells through controlling GLUT1 in vitro and in vivo. Thus, our finding provides new insights into the mechanism by which aspirin depresses liver cancer.

We examined the characteristics of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) and chlorobenzenes (CBzs) in the flue gas and fly ash of a municipal solid-waste incinerator in four locations: the outlet of the furnace, the outlet of the high-temperature superheater, the inlet of the semi-dry scrubber and the stack after air pollution control device (APCD) processing. Both PCDD/Fs and CBzs were mostly formed at low temperatures. The dominant PCDD/Fs generated in the gaseous phase were 23478-PeCDF and TCDF, and 124-TrCBz was the major CBz in both the gaseous and solid phase. More PCDD/Fs were found in the solid phase with the decrease of temperature, while CBzs exhibited the opposite trend. Furthermore, activated carbon with a low surface area and mesoporous volume showed low flue gas removal efficiencies for PCDD/Fs and CBzs in the flue gas. The fraction of PCDD/Fs in the solid phase largely decreased when the flue gas passed through the fabric filter. Additionally, the memory effects of the aged filters increased the fractions of 234678-HxCDF, 1234678-HpCDF and 1234678-HxCDD. Most important, the relationships between PCDD/Fs and CBzs in the flue gas and fly ash were analyzed, respectively. In the gaseous phase, most of the CBzs displayed high correlation coefficients with PCDD/Fs, especially 123-TrCBz (R2 > 0.8). In the solid phase, low correlation coefficients were found between CBzs and PCDD/Fs except for 135-TrCBz and 123-TrCBz (R2 = 0.8). A remarkable correlation was also found between 124-TrCBz in the flue gas and PCDD/Fs in the fly ash. We conclude that TrCBzs may be regarded as the best indicator for PCDD/Fs in both flue gas and fly ash.

In recent years, building microporous polyimides (MPIs) via choosing simple commercial aromatic monomers or concise experimental methods is still an issue worthy to explore. Herein, two cross-linkable aromatic alkynyl monomers (TAPM-PEPA and TAPA-PEPA) were prepared from a commercial alkynyl anhydride PEPA and two aromatic multi-amine TAPM (3D-tetrahedron) and TAPA (near 2D-planar) monomers with different topological structures. The crosslinked polyimides were prepared and endowed microporous features via one-pot thermal crosslinking polymerization in the diphenyl sulfone. The TAPM-PEPA-CL has higher BET surface area and total pore volume (736 m2 g-1 and 0.497 cm3 g-1) than those of the TAPA-PEPA-CL (351 m2 g-1 and 0.358 cm3 g-1). As the topological structure becomes more stereoscopic, CO2 adsorption capacity has been significantly improved from 9.6 wt% to 13.5 wt%. Furthermore, the TAPM-PEPA-CL and TAPA-PEPA-CL have excellent selectivity for CO2/CH4 (12.0–23.6) and CO2/N2 selectivity (54.4–57.6) at 273 K and 1 bar. These results reveal that the introduction of crosslinked structures and control of topological structures have potential application significance for preparing microporous polyimides based on cross-linkable aromatic alkynyl monomers, which is beneficial for the development of the field of gas adsorption and selectivity.

Hepatic steatosis induced inflammation is becoming increasingly prevalent in farmed fish. This study was conducted to investigate the protective effects of omega-3 polyunsaturated fatty acids (ω-3 PUFAs) against hepatic steatosis-induced inflammation and its potential molecular mechanisms in hepatocyte of large yellow croaker (Larmichthys crocea). We found that the hepatic steatosis-induced inflammation was relieved by ω-3 PUFAs, meanwhile, the Sirt1 activity and transcript expression was increased by ω-3 PUFAs. The increased Sirt1 activity can decrease the hepatic steatosis-induced inflammation. The protective effects of ω-3 PUFAs against hepatic steatosis-induced inflammation was reversed by the treatment with Sirt1 inhibitor EX-527. The nuclear translocation of nuclear transcription factor kappa-B (NF-κB) p65 was significantly decreased after ω-3 PUFAs treatments compared to the palmitic acid stimulation group. The ω-3 PUFAs induced cytoplasm translocation of NF-κB p65 was reversed by EX-527. Together, ω-3 PUFAs alleviate hepatic steatosis-induced inflammation through Sirt1-mediated nuclear translocation of NF-κB p65 subunit in hepatocytes of large yellow croaker. The present study provides important insight into the mechanisms of the protective effects of ω-3 PUFAs, providing theory bases for alleviating the hepatic steatosis induced inflammation of farmed fish, thereby offering great benefits to the aquaculture industry and fish consumers.

Methionine (Met) and cystine (CySS) are key sulfur donors in cell metabolism and are important nutrients for sustaining tumor growth; however, the molecular effects associated with their deprivation remain to be characterized. Here, we devised a xenograft mouse model to assess the impact of their deprivation on A549 xenografts and the xenograft-bearing animal. Results show that Met and CySS deprivation inhibits A549 growth in vitro, not in vivo. Deprivation was detrimental to the xenograft-bearing mouse, as demonstrated by weight loss and renal dysfunction. Differentially expressed proteins in A549 xenograft and mouse kidneys were characterized using quantitative proteomics. Functional annotation and protein-protein interaction network analysis revealed the enriched signaling pathways, including focal adhesion (Fn1) in the A549 xenograft, and xenobiotic metabolism (Cyp2e1) and glutathione metabolism (Ggt1) in the mouse kidney. Met and CySS deprivation inhibits the migratory and invasive properties of cancer cells, as evidenced by reduced expression of the epithelial to mesenchymal transition marker N-cadherin in A549 cells in vitro. Moreover, IGFBP1 protein expression was inhibited in both A549 xenograft and mouse kidneys. This study provides the first insights into changes within the proteome profile and biological processes upon Met and CySS deprivation in a A549 xenograft mouse model. This article is protected by copyright. All rights reserved.

To overcome the trade-off between permeability and selectivity of polymeric membranes and understand the influence of ultra-rigid units on gas separation performance, a series of PIMs (PIM-EN-x) based on spirodifluoranthene (EN) have been prepared. These polymers showed outstanding thermal stability. Their 5% weight loss temperature is higher than 503 °C. PIM-EN-x owned high BET surface area, ranging from 804 to 895 m2 g-1. With the increase of EN units, the gas permeability increased. The CO2 permeability of PIM-EN-40 is 11512 barrer, which is increased by 172% compared to PIM-1 with no loss in selectivity. The gas separation performance of PIM-EN-x surpassed the 2008 upper bound and near the latest upper bound. This work put forward a special structural unit to prepare polymers for CO2 separation and natural gas sweetening.

In this work, a simple method is proposed for the preparation of bidirectionally reversible light-responsive shape memory polyurethane (SMPU) bilayer. This SMPU bilayer consists of a 4,4-azodibenzoic acid (Azoa) containing SMPU (SMPU-Azoa) layer and a carbon black (CB) containing SMPU (SMPU-CB) layer. A reversible deformation is realized when the two sides are exposed to ultraviolet (UV) and infrared (IR) lights, respectively. The working mechanism is the trans–cis isomerization of SMPU-Azoa layer and the photo-thermal effect of SMPU-CB layer. The effect of the filler content and the thickness ratio of bilayer is systematically studied. The reversible bending angle of the SMPU bilayer can exceed 30° in 16 s for one cycle when the Azoa and CB contents are 5 wt% and 0.5 wt%, respectively, and the thickness ratio of SMPU-Azoa layer to SMPU-CB layer is 1/1.3. Furthermore, a micro-robot based on such LSMP bilayer is demonstrated.

A practical and general iron-catalyzed Wacker-type oxidation of olefins to ketones is presented, and it uses ambient air as the sole oxidant. The mild oxidation conditions enable exceptional functional-group tolerance, which has not been demonstrated for any other Wacker-type reaction to date. The inexpensive and nontoxic reagents [iron(II) chloride, polymethylhydrosiloxane, and air] can, therefore, also be employed to oxidize complex natural-product-derived and polyfunctionalized molecules.

Pancreatic carcinoma (PC) is a deadly form of cancer with poor overall survival. Currently, chemotherapy such as gemcitabine and 5-fluorouracil (5-FU) are the most popular medications that can improve survival, but rapid drug-resistance makes the search for more effective drugs urgent. Upon looking for natural components to treat PC, it was found that arenobufagin, a cardiac glycosides-like compound, showed significant effects on the gemcitabine-resistant pancreatic carcinoma cell line Panc-1 and the gemcitabine-sensitive cell line ASPC-1 at nanomolar concentrations. The present study used MTT and clonogenic survival assays to examine survival and proliferation, and western blotting to assess changes in the associated mitogen activated protein kinase and phosphoinositide 3-kinase pathways and expression of apoptosis-related proteins. The current study also detected the cell cycle by flow cytometry. Arenobufagin inhibited cell survival and proliferation, decreased the phosphorylation of key downstream proteins of K-Ras, including protein kinase B and extracellular signal related kinase, induced cell cycle G2/M phase arrest and apoptosis, and downregulated the level of phosphorylated epidermal growth factor receptor. Notably, the present data also showed that arenobufagin can enhance the sensitivity of PC cells to gemcitabine and 5-FU. In conclusion, arenobufagin could enhance the effect of gemcitabine and 5-FU on PC cells by targeting multiple key proteins. Therefore, arenobufagin has potential as anadjuvant therapy for the treatment of PC.

Abnormal lipid metabolism is a hallmark of tumorigenesis. Hence, the alterations of metabolism enhance the development of hepatocellular carcinoma (HCC). Aspirin is able to inhibit the growth of cancers through targeting nuclear factor κB (NF-κB). However, the role of aspirin in disrupting abnormal lipid metabolism in HCC remains poorly understood. In this study, we report that aspirin can suppress the abnormal lipid metabolism of HCC cells through inhibiting acyl-CoA synthetase long-chain family member 1 (ACSL1), a lipid metabolism-related enzyme. Interestingly, oil red O staining showed that aspirin suppressed lipogenesis in HepG2 cells and Huh7 cells in a dose-dependent manner. In addition, aspirin attenuated the levels of triglyceride and cholesterol in the cells, respectively. Strikingly, we identified that aspirin was able to down-regulate ACSL1 at the levels of mRNA and protein. Moreover, we validated that aspirin decreased the nuclear levels of NF-κB in HepG2 cells. Mechanically, PDTC, an inhibitor of NF-κB, could down-regulate ACSL1 at the levels of mRNA and protein in the cells. Functionally, PDTC reduced the levels of lipid droplets, triglyceride and cholesterol in HepG2 cells. Thus, we conclude that aspirin suppresses the abnormal lipid metabolism in HCC cells via disrupting an NFκB-ACSL1 signaling. Our finding provides new insights into the mechanism by which aspirin inhibits abnormal lipid metabolism of HCC. Therapeutically, aspirin is potentially available for HCC through controlling abnormal lipid metabolism.

An extensive investigation was conducted to understand polychlorinated dibenzo-p-dioxin and furan (PCDD/F) formation mechanisms and their relationships with chlorobenzenes (CBzs), chlorophenols (CPhs) and polycyclic aromatic hydrocarbons (PAHs) in the stack gas from two fluidized bed municipal solid waste incinerators in China. The toxic equivalent quantity (TEQ) value and the concentration of target compounds changed with the incinerator operating conditions. CPhs and PAHs were much more sensitive to operation conditions and were affected more easily by change. Only 2-monochlorophenol revealed a negative linear correlation (R2 ≥ 0.7). More than half of the PAHs revealed an adequate correlation model with PCDD/F concentration (R2 > 0.6), while CBzs showed almost perfect correlations with PCDD/Fs (R2 ≥ 0.8, significance level α ≤ 0.05). 123-Trichlorobenzene, 1234-tetrachlorobenzene and pentachlorobenzene revealed the best positive linear correlation (R2 > 0.9). PCDFs were revealed to be the best target compounds for indication due to the similar formation variation trend to that of other precursors. Unary and multiple linear regression equations with high coefficients of determination between several CBz, PAHs and PCDD/Fs, TEQ and PCDFs were established. The detailed relationships among PCDD/F homologues, isomers and other compounds and their formation mechanism were also discussed.

The formation of dibenzofuran (DF), polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and environmentally persistent free radicals (EPFRs) from 1,2,3-trichlorobenzene (1,2,3-TrCBz) over metal oxide / silica surface were investigated using a tubular furnace. PCDD/Fs increased exponentially from 250 to 550 °C over copper oxide / silica surface and PCDD/Fs had the maximum growth from 400 to 450 °C. The ratio of PCDD / PCDF was much less than 1, especially when the temperature raised from 450 to 550 °C. Pentachlorianated dibenzo-p-furan (PeCDF) dominated among the homologues, which contributed 45–61% to the total PCDD/Fs. Two peaks of the yield of DF occurred at 400 °C and 500 °C respectively. Furthermore, the oxygen contents have different effects for PCDD and PCDF formation, and low oxygen could promote PCDD production, especially for tetrachlorinated dibenzo-p-dioxin (TCDD). More PCDF were formed on the oxygen rich condition, indicating that the oxygen promoted the chlorination of DF. Iron oxides are better than copper oxides to catalyze the formation of PCDD/Fs from 1,2,3-TrCBzs at 350 °C, especially for PCDF. The major EPFRs on the catalysts were formed with g values in the range of 2.0040 to 2.0049, which were phenoxy radicals and semiquinone occurred with higher g value of 2.0075 when the temperature increased to 550 °C, and more EPFRs were produced with the temperature increasing. The addition of iron oxides reduced the spins concentrations of oxygen-centered radicals but increase the spins concentrations of signals with lower g values. The different possible formation pathways of PCDD and PCDF from 1,2,3-TrCBz over metal oxide surface were also proposed.

In recent years, linear polyimides of intrinsic microporosity have been widely used in the field of gas adsorption and separation because of their high BET surface area and microporous structures. Most of the microporous structures come from the twisted main-chain structures in the linear polyimides of intrinsic microporosity. Therefore, most linear polyimides (PI) without twisted structure have no porosity. Herein, to construct the linear polyimide with microporous structure, a sequence of microporous polyimides (PIs-CL) were constructed from the flexible linear polyimide precursors through the thermal crosslinking reaction. The polyimide precursors without twisted structure were synthesized from a well-designed diamine TFVBPA with cross-linkable ethynyl groups and several commercial dianhydrides (ODPA, BPDA, PMDA and 6FDA) by polycondensation to research the influence of the main-chain structure on the porous characters. The introduction of crosslinked structures gives the linear crosslinked polyimides (PIs-CL) with porous structures. The PIs-CL show obviously improved porosity (0.52–1.71 nm) and higher BET surface area (337–618 m2 g−1) than those of the uncrosslinked polyimides (PIs). Moreover, PIs-CL have favorable CO2 adsorption (5.7–9.3 wt%) as well as good CO2/N2 selectivity (34.4–58.5) at 273 K, which are better than other polyimides materials. The introduction of crosslinked structures is an effective way to improve microporous porosity and gas sorption performance.

A highly sensitive method for the detection of 6-mercaptopurine (MP) by resonance Rayleigh light scattering (RLS) method was developed. Gold nanoparticles (AuNPs) were synthesized by a modified seed method and characterized using transmission electron microscopy (TEM). AuNPs were bound to MP via covalent bonding to form the MP–AuNPs complex, which increased the RLS intensity of MP at 347 nm (increased by 65.7%). Under optimum conditions, the magnitude of the enhanced RLS intensity for MP–AuNPs was proportional to MP concentration in the range 0.0681–1.702 μg mL−1. The linear regression equation was represented as follows: ΔIRLS = 9.31 + 82.42c (r = 0.9948). The limit of detection (LOD, 3σ) was 3.32 ng mL−1. The system was applied successfully to detect MP in pharmaceuticals. MP recoveries were 99.9–101.7% with a relative standard deviation (RSD) (n = 5) of 0.59–0.77% for three synthetic samples, and 97.5–110.0% with an RSD of 0.98–2.10% (n = 5) for tablet samples.

A black phosphorus photodetector is utilized to investigate the light-scattering patterns of a silicon waveguide through wavelength- and polarization-dependent scanning photocurrent measurements. The photocurrent signals exhibit similar patterns to the light-intensity distribution of the waveguide calculated by finite-difference time-domain simulations, suggesting that photoexcited electron-hole pairs in the silicon waveguide can be injected into phosphorene to induce its photoresponse.

Three iso-energetic and iso-nitrogenous diets were fed to finishing pigs for 28 days to investigate the mammalian target of rapamycin (mTOR) and ubiquitin-proteasome signaling pathways of skeletal muscle by altering compositions of dietary energy sources. Diet A, diet B, and diet C contained 44.1%, 37.6%, and 30.9% starch; 5.9%, 9.5%, and 14.3% ether extract (EE); and 12.6%, 15.4%, and 17.8% neutral detergent fiber (NDF), respectively. An increase of mRNA expression of MuRF1 (1.09 ± 0.10 vs 1.00 ± 0.08) and MAFbx (1.10 ± 0.06 vs 1.00 ± 0.11) and a decrease of concentrations of plasma insulin (8.2 ± 0.8 vs 10.8 ± 1.2) and glucose (5.76 ± 0.12 vs 6.43 ± 0.33) together with mRNA expression of IRS (0.78 ± 0.19 vs 1.01 ± 0.05) and Akt (0.92 ± 0.01 vs 1.00 ± 0.05) were observed in pigs fed diet C compared with diet A. Protein levels of total and phosphorylated mTOR (0.31 ± 0.04 vs 0.48 ± 0.03 and 0.39 ± 0.01 vs 0.56 ± 0.02), 4EBP1 (0.66 ± 0.06 vs 0.90 ± 0.09 and 0.60 ± 0.12 vs 0.84 ± 0.09), and S6K1 (0.66 ± 0.01 vs 0.89 ± 0.01 and 0.48 ± 0.03 vs 0.79 ± 0.02) were decreased; however, total and phosphorylated AMPK (0.96 ± 0.06 vs 0.64 ± 0.04 and 0.97 ± 0.09 vs 0.61 ± 0.09) were increased in pigs fed diet C compared with diet A. In conclusion, diet C suppressed the mTOR pathway and accelerated the ubiquitin-proteasome pathway in skeletal muscle of finishing pigs.

A general iron-catalyzed carbonylative Suzuki–Miyaura coupling of aryl halides with arylborons is reported, using stoichiometric CHCl3 as the CO source. The high efficiency, economy, selectivity, and operational simplicity of this transformation make this method a valuable tool in organic synthesis. Importantly, the presented strategy allows effective 13C labeling simply by using the commercially available 13C-labeled CHCl3. On the basis of the initial mechanistic exploration, an aryl radical intermediate is proposed in the present carbonylation process.

Because of their unique properties, shape memory polymers (SMPs) have the potential to be used in various fields and are becoming one of the most desired shape memory materials. At present, it is generally complicated to prepare the two-way shape memory polymers (2W-SMPs) with both large reversible strain and high shape stability, which has hindered the real applications. By elaborately selecting poly(ε-caprolactone) diols (PCL-2OH) and poly(ε-caprolactone) triols (PCL-3OH) as prepolymers, a facile one-step method is employed to prepare two-way shape memory polyurethane (2W-SMPU). For this kind of SMPU, the reversible strain is found to be closely related to both the mass ratio of PCL-2OH to PCL-3OH and the initial applied stress. In this work, the smart devices of temperature-controlled lamp and gripper based on 2W-SMPU are designed and fabricated to show its two-way shape memory effect (2W-SME). The results show that its largest reversible strain can be as high as 21.3%. Moreover, it can lift up 150 times of its own weight and keep an almost constant reversible strain under a temperature-induced actuation within 50 consecutive cycles. Such 2W-SMPU materials could have lots of real applications.

Microporous polyimides have been extensively investigated for CO2 capture and separation applications. Here, the crosslinked structure and the polar CO2-philic trifluoromethyl group are introduced into the hyperbranched polyimides to construct the microporous polyimide networks for efficient CO2 capture. The HBPI-CL networks exhibit significant increased micropores (pore size less than 1 nm) surface area and volume ranging from 79 to 89 m2g-1 and 0.03–0.05 cm3 g−1. It is intriguingly found that the CF3TAPA-HBPI-CL have more abundant ultramicropores and exhibit higher CO2 uptake capacity and CO2/N2 selectivity (8.56 wt% and 33.3) than those of TAPA-HBPI-CL (7.47 wt% and 20.4) without the polar CO2-philic trifluoromethyl group at 273 K/1 bar. This work reveals that the introduction of polar CO2-philic trifluoromethyl group into crosslinked polyimides is an effective method to improve the CO2 adsorption capacity and selectivity of microporous polyimide, which can be also applied to other microporous polymers.

We fabricated three crosslinked porphyrin-based polyimides (PPBPI-CRs) from PEPHQDA, TAPP and three terminal anhydrides (PA, PEPA and PENA) via alkynyl groups crosslinking reactions. PPBPI-CRs had permanent porosities and revealed outstanding thermal stabilities. Affected by π-stacking and molecular sizes effect, with increasing conjugate and molecular sizes effect in different terminal anhydrides, porphyrin-based polyimides (PPBPIs) revealed decreased specific surface areas (106.8–8.3 m2 g−1), whereas, PPBPI-CRs showed increased BET surface areas (1.8–633 m2 g−1). Meanwhile, PPBPI-CRs had considerable CO2 uptakes (1.37, 2.01 and 2.37 mmol g−1) and isosteric heats of CO2 adsorption (34.8, 27.5 and 22.6 kJ mol−1). The PPBPI-CRs had CO2/N2 (39.83, 36.95, 40.08) and CO2/CH4 (14.13, 9.78, 10.87) separation selectivities.

Aptamers are short single-stranded nucleic acids that can bind to their targets with high specificity and high affinity. To study aptamer function and dynamics, the malachite green aptamer was chosen as a model. Malachite green (MG) bleaching, in which an OH- attacks the central carbon (C1) of MG, was inhibited in the presence of the malachite green aptamer (MGA). The inhibition of MG bleaching by MGA could be reversed by an antisense oligonucleotide (AS) complementary to the MGA binding pocket. Computational cavity analysis of the NMR structure of the MGA-MG complex predicted that the OH{sup -} is sterically excluded from the C1 of MG. The prediction was confirmed experimentally using variants of the MGA with changes in the MG binding pocket. This work shows that molecular reactivity can be reversibly regulated by an aptamer-AS pair based on steric hindrance. In addition to demonstrate that aptamers could control molecular reactivity, aptamer dynamics was studied with a strategy combining molecular dynamics (MD) simulation and experimental verification. MD simulation predicted that the MG binding pocket of the MGA is largely pre-organized and that binding of MG involves reorganization of the pocket and a simultaneous twisting of the MGA terminal stems around the pocket. MD simulation also provided a 3D-structure model of unoccupied MGA that has not yet been obtained by biophysical measurements. These predictions were consistent with biochemical and biophysical measurements of the MGA-MG interaction including RNase I footprinting, melting curves, thermodynamic and kinetic constants measurement. This work shows that MD simulation can be used to extend our understanding of the dynamics of aptamer-target interaction which is not evident from static 3D-structures. To conclude, I have developed a novel concept to control molecular reactivity by an aptamer based on steric protection and a strategy to study the dynamics of aptamer-target interaction by combining MD simulation and experimental verification. The former has potential application in controlling metabolic reactions and protein modifications by small reactants and the latter may serve as a general approach to study the dynamics of aptamer-target interaction for new insights into mechanisms of aptamer-target recognition.

Using density functional theory within the nonequilibrium Green's function formalism, we studied the spin transport through a binuclear ferric phthalocyanine (Fe2Pc2) connected to aurum nanowire electrodes. The Fe2Pc2 molecular devices exhibit a perfect spin filtering effect and larger magnetoresistance ratio even there not exist magnetic electrodes. The spin polarized transport comes from the magnetic proximity to the central Fe atoms at the center of each phthalocyanine that cause the molecule to develop finite magnetic character. Compared with traditional magnetic tunnel junction, the spin transport of the proposed molecular junction can be tuned only by altering the magnetization orientation of the Fe atom at the center of molecule.

Background Resistance to tamoxifen (TAM) frequently occurs in the treatment of estrogen receptor positive (ER+) breast cancer. Accumulating evidences indicate that transcription factor HOXB13 is of great significance in TAM resistance. However, the regulation of HOXB13 in TAM-resistant breast cancer remains largely unexplored. Here, we were interested in the potential effect of HBXIP, an oncoprotein involved in the acceleration of cancer progression, on the modulation of HOXB13 in TAM resistance of breast cancer. Methods The Kaplan-Meier plotter cancer database and GEO dataset were used to analyze the association between HBXIP expression and relapse-free survival. The correlation of HBXIP and HOXB13 in ER+ breast cancer was assessed by human tissue microarray. Immunoblotting analysis, qRT-PCR assay, immunofluorescence staining, Co-IP assay, ChIP assay, luciferase reporter gene assay, cell viability assay, and colony formation assay were performed to explore the possible molecular mechanism by which HBXIP modulates HOXB13. Cell viability assay, xenograft assay, and immunohistochemistry staining analysis were utilized to evaluate the effect of the HBXIP/HOXB13 axis on the facilitation of TAM resistance in vitro and in vivo. Results The analysis of the Kaplan-Meier plotter and the GEO dataset showed that mono-TAM-treated breast cancer patients with higher HBXIP expression levels had shorter relapse-free survivals than patients with lower HBXIP expression levels. Overexpression of HBXIP induced TAM resistance in ER+ breast cancer cells. The tissue microarray analysis revealed a positive association between the expression levels of HBXIP and HOXB13 in ER+ breast cancer patients. HBXIP elevated HOXB13 protein level in breast cancer cells. Mechanistically, HBXIP prevented chaperone-mediated autophagy (CMA)-dependent degradation of HOXB13 via enhancement of HOXB13 acetylation at the lysine 277 residue, causing the accumulation of HOXB13. Moreover, HBXIP was able to act as a co-activator of HOXB13 to stimulate interleukin (IL)-6 transcription in the promotion of TAM resistance. Interestingly, aspirin (ASA) suppressed the HBXIP/HOXB13 axis by decreasing HBXIP expression, overcoming TAM resistance in vitro and in vivo. Conclusions Our study highlights that HBXIP enhances HOXB13 acetylation to prevent HOXB13 degradation and co-activates HOXB13 in the promotion of TAM resistance of breast cancer. Therapeutically, ASA can serve as a potential candidate for reversing TAM resistance by inhibiting HBXIP expression. Electronic supplementary material The online version of this article (10.1186/s13045-018-0577-5) contains supplementary material, which is available to authorized users.

Survival following anthracycline-based chemotherapy remains poor among patients with most T-cell lymphoproliferative disorders. This may be attributed, at least in part, to cell-autonomous mechanisms of chemotherapy resistance observed in these lymphomas, including the loss of important tumor suppressors and the activation of signaling cascades that culminate in the expression and activation of transcription factors promoting cell growth and survival. Therefore, the identification of novel therapeutic targets is needed. In an effort to identify novel tumor dependencies, we performed a loss-of-function screen targeting ≈500 kinases and identified polo-like kinase 1 (PLK-1). This kinase has been implicated in the molecular cross-talk with important oncogenes, including c-Myc, which is itself an attractive therapeutic target in subsets of T-cell lymphomas and in high-grade ("double hit") diffuse large B-cell lymphomas. We demonstrate that PLK-1 expression is prevalent among these aggressive lymphomas and associated with c-myc expression. Importantly, PLK-1 inhibtion with the PLK-1 inhibitor volasertib significantly reduced downstream c-myc phosphorylation and impaired BRD4 binding to the c-myc gene, thus inhibiting c-myc transcription. Therefore, volasertib led to a nearly complete loss of c-myc expression in cell lines and tumor xenografts, induced apoptosis, and thus warrants further investigation in these aggressive lymphomas.

Clenbuterol interacting with bovine serum albumin (BSA) or lysozyme (LYS) in physiological buffer (pH 7.4) was investigated by the fluorescence spectroscopy and UV–vis absorption spectroscopy. The results indicated that clenbuterol quenched the intrinsic fluorescence of BSA and LYS via a static quenching procedure. The binding constants of clenbuterol with BSA and LYS were 1.16 × 103 and 1.49 × 103 L mol−1 at 291 K. The values of ΔH and ΔS implied that hydrophobic and electrostatic interaction played a major role in stabilizing the complex (clenbuterol–BSA or clenbuterol–LYS). In the presence of Fe2+, Fe3+, Cu2+, Mg2+, Ca2+, or Zn2+, the binding constants of clenbuterol to BSA or LYS had no significant differences. The distances between the donor (BSA or LYS) and acceptor (clenbuterol) were 2.61 and 2.19 nm for clenbuterol–BSA and clenbuterol–LYS respectively. Furthermore, synchronous fluorescence spectrometry was used to analyze the conformational changes of BSA and LYS.

A new assay of salmon sperm DNA at nanogram level was established based on enhanced resonance light scattering (RLS) signals of DNA with myricitrin and cetylpyridinium bromide dihydrate (CPB). The RLS spectral characteristics of DNA with myricitrin–CPB and the optimum conditions for determination of DNA samples have been studied. At pH 7.4, myricitrin–CPB could enhance the intensity of RLS signal of DNA at 468 nm. The enhanced RLS intensity was directly proportional to DNA concentration in the range of 0.076–4.2 μg mL −1 with a good linear relationship ( r = 0.9944). The detection limit was 4.1 ng mL −1 . The synthetic samples were analyzed with satisfactory results that the recovery was 100.9–102.6% and RSD was 1.4–2.1%, which proved that the new method was reliable and applicable.

Salbutamol interacting with deoxyribonucleic acid (DNA) was examined by fluorescence, UV absorption, viscosity measurements, and DNA melting techniques. The binding constants and binding sites were obtained at different temperatures by fluorescence quenching. The Stern-Volmer plots showed that the quenching of fluorescence of salbutamol by DNA was a static quenching. To probe the binding mode, various analytical methods were performed and the results were as follows: hyperchromic effect was shown in the absorption spectra of salbutamol upon addition of DNA; there was no appreciable increase in melting temperature of DNA when salbutamol was presented in DNA solution; the fluorescence intensity of salbutamol-DNA decrease with the increasing ionic strength; the relative viscosity of DNA did not change in the presence of salbutamol; the binding constant of salbutamol with double strand DNA (dsDNA) was much higher than that of it with single strand DNA (ssDNA). All these results indicated that the binding mode of salbutamol to DNA should be groove binding. The thermodynamic parameters suggested that hydrogen bond or van der Waals force might play an important role in salbutamol binding to DNA. According to the Förster energy transference theory, the binding distance between the acceptor and donor was 3.70 nm.

CO2 adsorption enhanced gasification process is a prospective technology to be used in hydrogen and power production with nearly zero CO2 emission. In this paper, a gasification kinetics steady state model is developed based on the chemical kinetics mechanism with the condition of fluidization. It is used to predict the parameters of gas phase and solid phase for a continuous flow reactor with steady state:The variation of distribution of components with gasification temperature and pressure are determined. Conceptual configurations of H-2 and power co-production system are designed with the integration of CO2 adsorption enhanced gasification process, H-2 separation unit, power generation unit and other auxiliary units. Mass and heat transfer between different parts are studied systematically by flow-sheet simulation and sensitivity analysis of parameters. According to the generalized exergy efficiency of the system, the influence of gasification temperature and pressure on the system performance is investigated and the optimum gasification temperature and pressure for system operation can be determined. (c) 2012 International Energy Initiative. Published by Elsevier Inc. All rights reserved.

The concentrations, homologue, and congener profiles, as well as the gas/particle distribution of polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs), chlorobenzenes (CBzs), chlorophenols (CPhs), and polyaromatic hydrocarbons (PAHs) from stack gas of two different municipal solid waste incinerators in China, were characterized. The incinerators were a stoker furnace incinerator equipped with the advanced air pollution control device (APCD) and a common circulating fluidized bed (CFB) furnace. The concentration of PCDD/Fs in the stack gas of the stoker incinerator ranged 0.011-0.109 ng international toxic equivalent factor (I-TEQ)/Nm3 and was below the current limit for PCDD/F emissions from the municipal solid waste incinerators (MSWIs) in China (0.1 ng I-TEQ/Nm3) in most of the cases. Moreover, the concentration of PCDD/Fs in the stack gas of the stoker incinerator was significantly lower than that of the CFB incinerator (0.734 to 24.6 ng I-TEQ/Nm3). In both incinerators, the majority of the total PCDD/F emissions (above 90%) ended up in the gas phase. 2,3,4,7,8-PeCDF, which occupied 24.3-43.6 and 32.5-75.6% of I-TEQ contribution in MSWIs A and B, respectively, was the most abundant congener. However, different types of incinerators and APCDs induced different congener and homologue distributions. The total concentration of CBzs from the stoker incinerator (0.05-3.2 μg/Nm3) was also much lower than that formed from the CFB incinerator (10.9-75.2 μg/Nm3). The phase distribution of CBzs followed the same pattern as with the PCDD/Fs. Moreover, the emission level of CBz was 100-1000 times higher than that of the PCDD/Fs, which determines the applicability of CBzs as indicators of PCDD/F emissions. High correlations between the emission concentrations of PCDD/Fs, TeCBz, and PCBz in specific ranges were revealed. Furthermore, high concentrations of CPhs (0.6-141.0 μg/Nm3) and PAHs (148.6-4986.5 μg/Nm3) were detected in the stack gases of MSWI B. In some cases, the concentrations were as high as the concentrations in the fumes exiting the boiler of one foreign stoker without flue gas purification indicating the abundance of CPh and PAH emissions in the stack gas of waste incinerators.

This study was conducted to clone and functionally characterize a full-length cDNA encoding arachidonate 5-lipoxygenase (Alox5) from large yellow croaker (Larmichthys crocea) and investigate its gene expression in response to graded dietary ratio of linolenic acid (ALA) to linoleic acid (LNA) (0.03, 0.06, 0.45, 0.90 and 1.51). An isolated 2372bp cDNA clone of Alox5 contained an open reading frame spanning 2025bp encoding a protein with the ability to modify arachidonate acid (AA) to 5-hydroxyeicosatetraenoic (5-HETE). In the liver, the Alox5 mRNA expression levels significantly increased to the maximum when the dietary ALA/LNA increased from 0.03 to 0.06, and then significantly decreased with dietary ALA/LNA increased to 1.51 (P0.05). In the kidney, the expression levels of Alox5 of fish fed diets with low dietary ALA/LNA (0.03-0.06) were significantly higher than those of fish fed diets with high dietary ALA/LNA (0.45-1.51) (P0.05). The dual-luciferase reporter assays showed that the nuclear factor kappa B (NF-κB) could act on cognate cis-acting elements in the promoter of Alox5 and increased the transcription of Alox5. Results of the present study suggested that the expression of Alox5 is higher in croakers fed high concentrations of LNA compared to those fed high concentrations of ALA, which might be regulated by NF-κB and contribute to the inflammation process by catalyzing the dioxygenation of AA.

The objective of this study was to establish a method for detecting fatty acid esters of chloropropanols [including 2-monochloropropane-1,3-diol (2-MCPD) ester and 3-monochloropropane-1,2-diol (3-MCPD) ester] in infant milk powder using isotope dilution and GC-MS. The fat fraction in infant milk powder samples was extracted and treated with sodium methylate–methanol to cleave the ester bonds of the 2- and 3-MCPD esters. The resultant 2- and 3-MCPDs in the samples were purified with matrix solid-phase liquid–liquid extraction and derivatized with heptafluorobutyryl imidazole for GC-MS analysis. Standard samples of deuterium isotope–labeled 2- and 3-MCPD palmitic acid double esters and stearic acid double esters were used as the internal standards. We also detected 2- and 3-MCPD ester contents in 88 commercial samples of infant formula milk powder using this system. The detection system we established showed a good linearity of 2- and 3-MCPD ester contents in serially diluted standard solutions within the concentration range 25−1000 μg/L, with r2 > 0.9995 and an LOD of 30 μg/kg for both of the MCPD esters. The recoveries of the two MCPD esters spiked at 25, 50, 100, and 200 μg/kg in blank infant formula milk ranged from 98.2 to 110.5%, with RSDs

Glioblastoma multiforme (GBM) is the most common and severe form of primary tumor in the central nervous system of adults which has poor prognosis and limited therapeutic options. Epidermal growth factor receptor (EGFR) inhibitor, such as gefitinib (brand name Iressa, ZD1839), has been approved as a targeted medicine for several types of tumor including glioblastoma multiforme. However, gefitinib exerted very limited effects on some glioblastoma multiforme patients after a period of treatment due to intrinsic and acquired drug resistance. β-Elemene, a natural plant drug extracted from Curcuma wenyujin, has shown promising anticancer effects against a broad spectrum of tumors. In the present study, we found that β-elemene could enhance the chemosensitivity of glioblastoma multiforme cells to gefitinib. The combination medication of β-elemene and gefitinib not only inhibited the survival and proliferation of glioblastoma multiforme cells via inhibition of EGFR signaling pathway but also induced more distinct apoptosis and autophagy in the glioblastoma multiforme cells than the gefitinib monotherapy. These results showed that β-elemene might be one potential adjuvant to enhance the effect of EGFR inhibitor and reduce the resistance of gefitinib in glioblastoma multiforme.

Fluorescence spectra, absorption spectra, melting temperature, ionic strength effect, and viscosity experiments were described that characterize the interaction of eugenol with salmon sperm DNA in vitro. Eugenol was found to bind but weakly to DNA, with binding constants of 4.23×10 3 , 3.62×10 3 and 2.47×10 3 L mol −1 at 18, 28 and 38 °C respectively. The Stern–Volmer plots at different temperatures suggested that the quenching type of fluorescence of eugenol by DNA was a static quenching. Both the relative viscosity and the melting temperature of DNA were increased by the addition of eugenol. The changes of ionic strength had no affect on the binding. In addition, the binding constant of eugenol with single stranded DNA (ssDNA) was larger than that of eugenol with double stranded DNA (dsDNA). These results revealed that the binding mode of eugenol to DNA was intercalative binding. The thermodynamic parameters Δ H , Δ G and Δ S were also obtained according to the Van't Hoff equations, which suggested that hydrogen bond or van der Waals force might play an important role in a binding of eugenol to DNA. Based on the theory of the Forster energy transference, the binding distance between DNA and eugenol was determined as 4.40 nm, indicating that the static fluorescence quenching of eugenol by DNA was also a non-radiation energy transfer process.

Two new systems for measuring DNA at nanogram levels by a resonance Rayleigh light scattering (RLS) technique with a common spectrofluorometer were proposed. In the presence of cetyltrimethylammonium bromide (CTAB), the interaction of DNA with hesperetin and apigenin (two effective components of Chinese herbal medicine) could enhance RLS signals with the maximum peak at 363 and 433 nm respectively. The enhanced intensity of RLS was directly proportional to the concentration of DNA in the range of 0.022-4.4 μg mL(-1) for DNA-CTAB-hesperetin system and 0.013-4.4 μg mL(-1) for DNA-CTAB-apigenin system. The detection limit was 2.34 ng mL(-1) and 2.97 ng mL(-1) respectively. Synthetic samples were measured satisfactorily. The recovery of DNA-CTAB-hesperetin system was 97.3-101.9% and that of DNA-CTAB-apigenin system was 101.2-109.5%.