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Previous studies on epoxy foams were subjected to the specific property, and improvements in thermal insulation or dielectric property were usually accompanied by the sacrifice of mechanical strength or thermal stability. The current research reported a high‐performance epoxy foam by the pre‐curing process using E‐51/DDS and expandable microsphere (EMP) as polymer matrix and physical blowing agent, respectively. The effect of EMP loading on the structure & property of epoxy foam was reported. The mean diameter of E‐51/EMP foam was in the range of 19–21 μm. The compression property of E‐51/EMP foam was fit for the power‐law model and its integrity was well maintained during compressive test. Compared with bulky epoxy, a significant decrease of thermal conductivity of 62.93% was observed in 10 wt% EMP‐filled epoxy foam. E‐51/EMP foam showed superior thermal stabilities, with a T5% of over 300°C. The dielectric constant was decreased by 54.5% from 4.92 in bulky epoxy to 2.24 in E‐51/EMP foam (10 wt% EMP). Notably, there was a percolation phenomenon of EMP (6 wt%) regarding on the structure & property of E‐51/EMP foam. This study provides lightweight, robust, high‐temperature‐resistant, and low‐dielectric‐constant epoxy foams with the wide application prospects in buoyant, electronic packaging, and energy‐saving industries. [ABSTRACT FROM AUTHOR]

Bifunctional phthalonitrile‐benzoxazine (PNBZ) usually suffers from slow‐curing characteristics. Recently, we unexpectedly observed a waste liquid containing PNBZ solution and excess ethylenediamine (EDA) had turned into a gel at room temperature. Since the report on the PNBZ gelling phenomenon below 150°C was rare, this accidental finding manifested the possible formation of PNBZ gel at low temperatures. By varying the EDA molar ratio, PNBZ gels with different microstructures were successfully realized at the low temperature of 50°C. Through the differential scanning calorimetry, thermogravimetric analyse (TGA), and Fourier transform infrared technique, the driving force behind the gel formation was found to be the low‐temperature copolymerization between the amino group of EDA and the BZ ring of PNBZ, resulting in the amine‐containing intermediate. PNBZ gel was thermally unstable, but was mechanically robust. The current method was also universal to realize polymer or composite gels for a class of slow‐curing PNBZ resin (i.e., allyl‐containing PNBZ gel and its carbon nanotube‐filled composite gel). This study not only expands our understanding of the low‐temperature polymerization behavior of PNBZ but also provides a versatile strategy for low‐temperature preparation of PNBZ‐based gels. Making the most of current approach, it is believed that multifunctional PNBZ‐based gels will be developed for various applications. [ABSTRACT FROM AUTHOR]

In this study, a series of nonsolvents including ethyl acetate (EAC), acetic acid (HAC), n‐butyl alcohol (NBA), iso‐propyl alcohol (IPA) and ethanol (EA) were selected during the phase inversion process of poly(arylene ether nitrile) (PEN) films. The mechanism of film formation was tightly related with the interactions among polymer, solvent and nonsolvent. In the case of EAC, the aggregated sphere in P‐EAC confirmed the in situ aggregate mechanism of polymer chains during the phase inversion process. As the nonsolvent‐polymer interaction increases from HAC, NBA, IPA to EA, the phase inversion mechanism was gradually changed from the delayed to transient, as verified by the morphology transformation from spongy‐like to finger‐like. Dielectric, mechanical properties of these PEN films are tightly related with the morphological features, while their thermal properties are similar. Among them, P‐EAC show the optimal properties for potential application in the low‐k films, with a dielectric constant, Td5%, tensile strength of 1.99, 515.84°C, and 36.08 MPa, respectively. This work can provide references for tailoring the structures and properties of PEN films through rational selection of nonsolvent via the phase inversion method. [ABSTRACT FROM AUTHOR]

Chinese hamster ovary (CHO) cells have been used as the industry standard for the production of therapeutic monoclonal antibodies for several decades. Despite significant improvements in commercial‐scale production processes and media, the CHO cell has remained largely unchanged. Due to the cost and complexity of whole‐genome sequencing and gene‐editing it has been difficult to obtain the tools necessary to improve the CHO cell line. With the advent of next‐generation sequencing and the discovery of the CRISPR/Cas9 system it has become more cost effective to sequence and manipulate the CHO genome. Here, we provide a comprehensive de novo assembly and annotation of the CHO‐K1 based CHOZN® GS−/− genome. Using this platform, we designed, built, and confirmed the functionality of a whole genome CRISPR guide RNA library that will allow the bioprocessing community to design a more robust CHO cell line leading to the production of life saving medications in a more cost‐effective manner. [ABSTRACT FROM AUTHOR]

The morphology transition from primary to hierarchical adsorption‐type microporous domains of amphiphilic block copolymer (BCP) honeycomb‐structured films is demonstrated by a facile swollen based breath figure (BF) method. The characteristic parameters of poly(4‐vinylpyridine)‐block‐polystyrene (P4VP‐b‐PS) hierarchical micro‐ and submicroporous films can be controlled by changing the length of segments or subsequent swelling conditions. A plausible mechanism is demonstrated in this research. A typical amphiphilic BCP with very low volume content of hydrophilic blocks (fP4VP ≤ 0.050) can efficiently stabilize water droplets and inherently assist in the formation of morphology transition. This BCP film can be used for Cr(VI) removal from wastewater, which additionally has enormous potential application in the field of novel optical devices, soft lithography, size‐selective separation, etc. [ABSTRACT FROM AUTHOR]

We propose a two‐dimensional (2D)/ three‐dimensional (3D) mixed display system based on polarization division multiplexing. The polarization division multiplexing device is composed of a polarization switching layer, a polarization‐dependent liquid crystal micro‐lens array (LCMLA) and a scattering polarizer. According to the polarization state of incident light switched by the polarization switching layer, the combined action of polarization‐dependent LCMLA and scattering polarizer can form both point light source array for 3D display and scattered light source for 2D display. The 2D/3D mixed images can be reconstructed through the precise control of the polarization direction of each pixel. The advantage of the proposed system is that a point light source array and a surface light source are formed only by adjusting the state of the polarization switching layer. What's more, our proposed system has low driving voltage and relatively compact system volume. [ABSTRACT FROM AUTHOR]

The development of two‐dimensional (2D)/three‐dimensional (3D) switchable displays in the display market is limited due to the narrow depth of 3D display mode. In this paper, we propose a depth‐enhanced 2D/3D switchable display based on integral imaging that stacks multiple polarization switching layers and multiple polarization‐dependent liquid crystal micro‐lens arrays (LCMLAs) together. According to the change of the incident polarization state by the polarization switching layer, the polarization‐dependent LCMLA can realize the focusing effect and transmission effect respectively. Because different layers of polarization‐dependent LCMLA have different gaps (g) and the combination of different layers of polarization‐dependent LCMLA obtains different focal lengths (f), hence, multiple central depth planes can be generated to improve the depth of field (DOF) of the 3D mode. The 2D display mode is realized when all the layers of the polarization‐dependent LCMLA are in transmission effect. We experimentally developed a prototype of the proposed 2D/3D switchable display with two polarization switching layers and two polarization‐dependent LCMLAs. The results show that the DOF of the prototype is easily increased by more than two times. At the same time, the 2D image is also clearly presented in 2D mode without any distortion. [ABSTRACT FROM AUTHOR]

In this study, the carbon nanotubes (CNTs) are successively coated via sol‐gel method with SiO2 (SiO2@CNTs), followed by grafting with 3‐merraptnpropyltrimethnxysilane and oxidation with hydrogen peroxide to yield dual‐modified CNTs (SSiO2@CNTs). The SSiO2@CNTs material is applied to prepared chitosan (CS) based composite proton exchange membranes by the incorporation of various content of SSiO2@CNTs, the structure and properties of as‐prepared composite membranes are fully investigated. Compared to pristine CS membrane, the SSiO2@CNTs‐filled composite membranes show improved thermal stability, mechanical stability, and methanol resistance, owing to the effective interface interaction and good compatibility between SSiO2@CNTs and CS matrix. Additionally, the doping of SSiO2@CNTs also generates a positive effect on the electrochemistry performance, due to the construction of abundant transport channel and providing more proton sources or proton sites. Particularly, the CS/SSiO2@CNTs‐7 membrane exhibits tensile strength of about 40.1 MPa and proton conductivity of 35.8 mS cm−1 at 80 °C, which is almost 1.6 and 2.0 times higher than pure CS membrane, and lower methanol permeability of 0.9 × 10−6 cm2 s−1. The direct methanol fuel cell performance (DMFC) of CS/SSiO2@CNTs‐7 membrane is also improved with open circuit voltage of 0.67 V and maximum power density of 60.7 mW cm−2 at 70 °C. [ABSTRACT FROM AUTHOR]

Aim: Given the increasing prevalence of hysteromyoma among the Chinese rural women of childbearing age, it is imperative that more attention should be given to researching risk factors that predispose women to this condition so that early preventive measures may be taken. Our study investigates potential risk factors for uterine fibroids such as participants' demographic characteristics (age, ethnicity, education), physiological characteristics (age at menarche, primiparous age), and the occurrence of several different female reproductive diseases (vaginitis, pelvic inflammatory disease). Methods: 2200 rural women of reproductive age were screened from a cross‐sectional study carried out in the northern Anhui province. Data were collected by questionnaire surveys, gynecological and laboratory examinations and were subjected to univariate and multivariate analysis to evaluate the risk factors for uterine fibroids. Results: Of the 2200 women, 440 had uterine fibroids. In general, women with endometriosis, ovarian cysts and early menarche were more likely to suffer from hysteromyoma. Factors including higher parity, late age of first childbirth, and a regular menstrual cycle were associated with the reduced risk of uterine fibroids. Conclusions: Our findings indicate that parameters such as earlier age of menarche, early primiparous age, lower parity and a variety of female reproductive diseases were associated with an increased risk of uterine fibroids. These findings may be used to guide the formulation of effective prevention and intervention protocols to improve the reproductive health of rural women. [ABSTRACT FROM AUTHOR]

In this paper, we propose a depth‐enhanced integral imaging display based on bifocal lens array. The bifocal lens array consists of a small lens array with plano‐convex circular lens units and a large lens array with square lens units. The proposed display device generates two central depth planes and stitches two reconstructed 3‐D images in depth, which largely improves the depth of field. The experimental results indicate that the proposed structure reconstructed 3‐D image with the depth of field as large as 150.8 mm, which is double of conventional integral imaging display. [ABSTRACT FROM AUTHOR]

Background: Adequate flap volume is key to maintaining oral function after oral cancer surgery. This study aimed to evaluate changes in radial forearm free flap (RFFF) volumes after 1 year of follow‐up following ablative tumor surgery in the head and neck. Methods: A prospective study that recorded the clinical data of 20 patients with head and neck cancer who underwent RFFF reconstruction. Magnetic resonance (MR) and Mimics Research 19.0 software were used to measure the RFFF volumes at 1, 3, 6, and 12 postoperative months. Results: Compared with one postoperative month, the RFFF volume decreased by 15.5%, 29.4%, and 42.0% at 3, 6, and 12 months, respectively, after surgery. A significant positive correlation between postoperative radiotherapy and RFFF volume changes was detected. Conclusion: The volume of RFFF decreases with time. It is recommended to use overcorrection, with a 40% increase in RFFF volume, to reconstruct head and neck tumor‐related defects. [ABSTRACT FROM AUTHOR]

New types of metal–organic framework based hybrid materials are designed and prepared, which involving the hybridization of various content of boron phosphate (BPO4) with the precursor of HKUST‐1. The structure of obtained HKUST‐1/BPO4 hybrid materials (HB) is fully investigated, and then applied to construct sulfonated poly (ether ether ketone) (SPEEK) based proton exchange membranes (SPEEK/HB). Owing to effective interactions between hybrid materials and SPEEK matrix, the achieved composite membranes reflect a considerable improvement in mechanical and thermal stability, oxidative stability, methanol permeation, and proton conductivity. In particular, the tensile strength of SPEEK/HB‐20 composite membrane is 41.3 MPa, which is 1.5 times higher than pristine SPEEK, and the methanol permeability reduced to one‐third of SPEEK at the same time. The SPEEK/HB‐10 displays the highest proton conductivity of 37.4 mS cm−1 at 80 °C, which is obviously higher than pristine SPEEK. These results reveal that the hybridization of HKUST‐1 with BPO4 provide a promising candidate in the modification of proton exchange membranes (PEMs), and this strategy also possess great application potential in other types of MOFs‐based hybrid materials. [ABSTRACT FROM AUTHOR]

The reflective augmented reality 3D display based on lens‐type integral imaging is presented by using a reflective polarizer. The reflective polarizer functions as a reflective imaging device as well as an image combiner. We confirmed that the proposed system could receive the 3D image and reflect image simultaneously. [ABSTRACT FROM AUTHOR]

Herein we present a new viologen‐based radical‐containing metal–organic framework (RMOF) Gd‐IHEP‐7, which upon heating in air undergoes a single‐crystal‐to‐single‐crystal transformation to generate Gd‐IHEP‐8. Both RMOFs exhibit excellent air and water stability as a result of favorable radical‐radical interactions, and their long‐lifetime radicals result in wide spectral absorption in the range 200–2500 nm. Gd‐IHEP‐7 and Gd‐IHEP‐8 show excellent activity toward solar‐driven nitrogen fixation, with ammonia production rates of 128 and 220 μmol h−1 g−1, respectively. Experiments and theoretical calculations indicate that both RMOFs have similar nitrogen fixation pathways. The enhanced catalytic efficiency of Gd‐IHEP‐8 versus Gd‐IHEP‐7 is attributed to intermediates stabilized by enhanced hydrogen bonding. [ABSTRACT FROM AUTHOR]

A composite proton exchange membrane chitosan (CS)/attapulgite (ATP) was prepared with the organic–inorganic compounding of ATP and CS. The composite membranes were characterized by scanning electron microscope (SEM), X‐ray diffraction (XRD), and fourier transform infrared spectroscopy (FTIR). The mechanical properties, thermal stability, water uptake, and proton conductivity of the composite membranes were fully investigated. The composite membranes exhibited an enhanced mechanical property, dimensional and thermal stability compared to CS membrane, owing to the interface interaction between ATP and CS. The maximum tensile strength of 53.1 MPa and decomposition temperature of 223.4°C was obtained, respectively. More importantly, the proton conductivity of the composite membrane is also enhanced, the composite membrane with 4 wt% ATP content (CS/ATP‐4) exhibited the highest proton conductivity of 26.2 mS cm−1 at 80°C with 100% relative humidity, which is 25.1% higher than pure CS membrane. These results may explore a simple and green strategy to prepare CS‐based PEMs, which have a great potential in the application of proton exchange membrane fuel cells. [ABSTRACT FROM AUTHOR]

To obtain the effect of the viewpoint number on the accommodation response of human eyes, we measure the accommodation response of the human eyes when we view the 3D images with 8×8, 6×6, 4×4, 2×2, 1×1 viewpoints, and compare the results with the accommodation response when viewing real target. [ABSTRACT FROM AUTHOR]

The chitosan (CS) matrix‐based composite proton exchange membranes (CS/QATP) were prepared by the incorporation of organic‐modified attapulgite (QATP) into CS, through an organic‐inorganic composite synthesis method. The QATP was obtained by the modification with silane coupling agent (octadecyldimethyl [3‐trimethoxysilylpropyl] ammonium chloride). The morphology, crystallinity, thermal and mechanical property, dimensional stability, and proton conductivity of CS/QATP composite membranes were investigated. The compatibility and dispersibility of QATP in CS matrix were significantly improved with enhanced interfacial interaction. The dimensional and thermal stability of the CS/QATP composite membranes were improved compared with pure CS film, owing to good dispersion and lower water uptake. Especially, the composite membrane with 2 wt% QATP (CS/QATP‐2) exhibits the highest mechanical strength and proton conductivity, which is much higher than pure CS film. These results indicated that CS/QATP composite membranes have a great potential for proton exchange membranes applications. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO) has triggered significant attention as a new type of self‐assembly membrane material. However, the low filtration flux and unstable performance of GO membrane limit its practical application. Hence, in this work, layered double hydroxides (LDHs), as a 2D material with double‐layer channel structure and positive electricity, were self‐assembled with GO at weight ratio of 7:3 by electrostatic interaction. Then, the GO/LDH hybrids combined with polydopamine (PDA) to obtain stable and high‐flux GO‐based membranes through vacuum filtration and the structure and morphology of as‐prepared samples were characterized by FT‐IR, XRD, XPS, and SEM. Furthermore, the separation performance and surface electronegativity of membranes were tested via pure water flux, rejection efficiency, recycle experiments, and zeta potential. Results revealed that the stability and flux of composite membrane were enhanced significantly compared with neat GO‐based membrane. Further, the dye rejection rate of methylene blue (MB) is higher than Congo red (CR) and rhodamine B (Rh B) and reached to 99.8%. [ABSTRACT FROM AUTHOR]

Abstract: Background: The anterolateral thigh (ALT) free flap has been an extremely versatile flap. The purpose of this study was to propose comprehensive functional assessments of the donor site. Methods: A total of 33 ALT flaps were enrolled prospectively. Objective assessments included isokinetic testing of the knee, and electromyographic examination of the lateral femoral cutaneous nerve (LFCN). The Patient and Observer Scar Assessment Scale (POSAS) was used to subjectively assess the donor‐site scar. Results: On the donor side, a significant decrease in most isokinetic muscle strength values was obvious 1 year postoperatively (P < .01). The normal side showed a compensatory increase 1 year postoperatively in the majority of isokinetic muscle strength values (P < .05). The majority of patients (70%) showed decreased sensory conduction velocity of the LFCN or no response to the microcurrent stimulation postoperatively. The aesthetic outcome was satisfactory. Conclusion: The decline in functional parameters at the donor‐site was common. However, much more research is needed. [ABSTRACT FROM AUTHOR]

Abstract: Panax ginseng is widely consumed as a functional food in the form of tea, powder, capsules, among others, and possesses a range of pharmacological activities including adaptogenic, immune‐modulatory, anti‐tumor, anti‐aging and anti‐inflammatory effects. The aim of this study was to identify and quantify the major ginsenosides and their metabolites in rat plasma, urine and feces after administration of P. ginseng extract using LC–MS/MS. We collected rat plasma samples at 0.5, 1, 2, 4, 8, 12, 24 and 48 h, and the amounts of urine and fecal samples accumulated in 24 h. Fourteen major ginsenosides and their metabolites were observed in fecal samples at high levels; however, low levels of 11 ginsenosides were detected in urine samples. The pharmacokinetics of the major ginsenosides and their metabolites was investigated in plasma. The results indicated that the maximum plasma concentration, time to maximum concentration and area under the curve of compound K were significantly greater than those of other ginsenosides. This study thus provides valuable information for drug development and clinical application of P. ginseng. [ABSTRACT FROM AUTHOR]

In this study, calcium carbonate (CaCO3) whiskers were grafted with poly(methyl methacrylate) (PMMA) by in situ emulsion polymerization using γ-methacryloxy propyl trimethoxyl silane (γ-MPS) as a coupling agent, and the properties of resultant whisker were determined using Fourier transform infrared (FTIR) spectroscopy, energy dispersive spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), and thermogravimetric analysis (TGA). The results show that PMMA has been successfully grafted onto the surface of CaCO3 whiskers and the maximum grafting degree (Gd) is 3.75%. The scanning electron microscopy (SEM) micrographs of the tensile-fractured surfaces show that modified CaCO3 whiskers have strong interfacial adhesion to the poly(vinyl chloride) (PVC) matrix. The tensile strength increases from 44.0 MPa for PVC composite with unmodified whisker to 49.5 MPa for that with grafted whisker. The dynamic mechanical analysis (DMA) and TGA results indicate that the composites reinforced by modified CaCO3 whiskers have much higher modulus, glass transition temperature, and better thermal stability than their counterparts reinforced by unmodified CaCO3 whiskers. POLYM. COMPOS., 38:2753-2761, 2017. © 2015 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

ABSTRACT Background The free fibula flap has become popular for mandibular reconstruction. The purpose of this study was to propose comprehensive functional assessments of the donor site. Methods Thirty free fibula flaps for mandible reconstruction were prospectively enrolled in the study. Objective assessments included isokinetic testing of the ankle joint, electromyographic examination of the superficial peroneal nerve (SPN), and preoperative and postoperative foot scans. The Patient and Observer Scar Assessment Scale (POSAS) was used to subjectively assess the donor site. Results The isokinetic values of the donor side showed a significant decrease 1 year postoperatively. The results of the electromyographic test of the SPN were categorized as 3 types. The plantar center pressure shifted to the heel on the donor side 6 months postoperatively. The aesthetic outcome was satisfactory. Conclusion The functional parameters of the donor site indeed declined in our assessments. Further refinements in the surgical technique are needed to improve the donor site status. © 2016 Wiley Periodicals, Inc. Head Neck 39: 279-287, 2017 [ABSTRACT FROM AUTHOR]

Objective Cell adhesion-mediated drug resistance ( CAM- DR) is one of the mechanisms underlying the drug resistance in multiple myeloma ( MM). Ubiquitin-specific protease 14 ( USP14) is downregulated in the apoptotic model and upregulated in the adhesive model of MM. This study was undertaken to determine the role of USP14 in CAM- DR of MM cells. Methods We examined the expression of USP14 in the apoptotic model of MM. The mechanism of USP14 in the process of apoptosis was further explored by flow cytometry assay and co-immunoprecipitation. We then performed the cell co-culture and adhesion assay and cell viability assay to investigate the effect of USP14 on adhesive rate and drug resistance in MM. Results We discovered that USP14 played a negative role in cell apoptosis, which is correlated with Bcl-xl. Moreover, overexpression of USP14 in MM cell adhesion model could enhance the ability of cell adhesion by regulating Wnt-signaling pathways, thereby promoting the CAM- DR in MM. Conclusion USP14 participates in CAM- DR of MM through acting as a bridge between Bcl-xl apoptotic pathway and Wnt-signaling pathways and may be represented as a good candidate for pursuing clinical trials in MM. [ABSTRACT FROM AUTHOR]

Aims Androgen-deprivation therapy ( ADT) is a main treatment option for patients with prostate cancer ( PCa), but its effect on cognition remains unclear. The primary purpose of this cross-sectional case-control study was to evaluate the effects of ADT on cognition in Chinese PCa patients. Methods Participants included PCa patients who had undergone ADT ( ADT group, n = 33) and patients who did not undergo ADT (non- ADT group, n = 32), as well as age- and education-matched healthy controls ( HC group, n = 35). All participants were examined using the neuropsychological battery aimed at assessing several cognitive domains including attention, memory and information processing performance. Results The ADT group obtained significantly worse scores than the non- ADT and HC groups in the following neuropsychological tests: Recognition ( P < 0.01), WAIS Digit Span forward ( P < 0.05), Trailmaking B ( P < 0.01) and Stroop Interference test ( P < 0.01). No significant difference was found between the non- ADT and HC groups ( P > 0.05). Conclusions Chinese PCa patients receiving ADT showed cognitive impairments in several domains including memory, attention and information processing performance. [ABSTRACT FROM AUTHOR]

Multi-walled carbon nanotubes (MWCNTs) were acidified with nitration mixture, and the Fe2O3-MWCNTs (iron oxide coated multi-walled carbon nanotubes) hybrid material via sol-gel method then verified the results through scanning electron microscope, X-ray diffraction, and thermal gravimetric analysis. We modified the hybrid material with silane coupling agent (KH560), Fe2O3-MWCNTs/epoxy, MWCNTs/epoxy composites coating, and the pure epoxy coatings were respectively prepared. The properties of the composite coatings were tested through the electrochemical workstation (electrochemical impedance spectroscopy), shock experiments, and thermal gravimetric analysis. Finally, we used scanning electron microscope to observe the surface conditions of the coatings. The results show that Fe2O3-MWCNTs have good dispersion in the epoxy resin, and the Fe2O3-MWCNTs/epoxy composite coatings have enhanced mechanical properties and corrosion resistance. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Analyses of firings by the up-and-down method were employed to gain a better understanding of the influences of foil bridge width, foil thickness, flyer thickness, and barrel length on the sensitivity of exploding foil initiators. Characterization was performed via the mean threshold voltage. The results showed that the mean threshold voltage of exploding foil initiators was reduced by 16 % when the foil bridge width was reduced from 0.4 mm to 0.3 mm, which means that a reduced foil bridge width could decrease the mean threshold voltage of exploding foil initiators as suggested by theoretical analysis. The mean threshold voltage of exploding foil initiators was reduced by 20 % as the flyer thickness was decreased from 50 μm to 25 μm, which could be an efficient way to improve the sensitivity of exploding foil initiators. The flyer accelerated to over 90 % maximum velocity after flying 0.15 mm in a fine barrel, which revealed that exceeding a barrel length of 0.15 mm has little effect on the performance of exploding foil initiators. [ABSTRACT FROM AUTHOR]

ABSTRACT Objective To investigate the association between calcium channel blockers (CCBs) and increased risk of breast cancer. Methods Using terms related to breast cancer and CCB, we searched PubMed, Embase, and Web of Science for studies on CCB use and the associated risk of breast cancer published before July 2013. Two evaluators independently selected observational studies on the basis of predetermined selection criteria, and 11 studies were included in the meta-analysis. Summary estimates were obtained using fixed-effects or random-effects models as appropriate, and subgroup analyses, sensitivity analyses, and publication bias tests were performed. Results Our meta-analysis consisted of 11 studies, including four case-controls, two nested case-controls, and five cohort studies. The odds ratios (ORs) of the association between CCB use and breast cancer were 1.11 (95% confidence interval [CI] 0.93-1.33) overall, 1.04 (95%CI 0.92-1.18) for prospective studies, and 1.33 (95%CI 0.79-2.25) for retrospective studies. There was a positive association between immediate-release CCB use and risk of breast cancer (OR 1.88, 95%CI 1.37-2.60). Conclusions There is no evidence that CCB use is associated with an increased risk of breast cancer. However, there may be a positive association between immediate-release CCB use and risk of breast cancer, but given the current preference for use of sustained-release CCB, the potential clinical impact of this association is limited. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Chemoresistance in hepatocellular carcinoma ( HCC) is associated with multiple cellular responses to environmental stresses, such as nutrient deprivation and hypoxia. Nevertheless, whether ER stress resulting from nutrient deprivation and tumor hypoxia contributes to drug resistance remains unclear. Melatonin increased the efficacy of chemotherapeutic drugs in hepatocellular carcinoma in our previous studies. However, the effects of melatonin on endoplasmic reticulum ( ER) stress-induced resistance to chemotherapeutic agents in HCC have not been tested. The effect of the endoplasmic reticulum ( ER) stress response during resistance of human hepatocellular carcinoma cells against doxorubicin was investigated in this study. Pretreatment of HepG2 and SMMC-7721 cells (two human hepatocellular carcinoma cell lines) with tunicamycin, an ER stress inducer, drastically decreased the rate of apoptosis generated by doxorubicin. Interestingly, co-pretreatment with tunicamycin and melatonin significantly increased apoptosis induced by doxorubicin. Simultaneously, the expression of phosphorylated AKT (p- AKT) was elevated in HepG2 and SMMC-7721 cells given tunicamycin but reduced in the presence of melatonin. Furthermore, consistent with inhibition of AKT activation by using the PI3K inhibitor LY294002, melatonin elevated the levels of CHOP (C/ EBP-homologous protein) and reduced the levels of Survivin (a member of the inhibitor of apoptosis protein family)suggesting that inhibition of the PI3K/ AKT pathway by melatonin-reversed ER stress-induced resistance to doxorubicin in human hepatocellular carcinoma cells. These results demonstrate that melatonin attenuates ER stress-induced resistance to doxorubicin in human hepatocellular carcinoma cells by down-regulating the PI3K/ AKT pathway, increasing the levels of CHOP and decreasing the levels of Survivin. [ABSTRACT FROM AUTHOR]

Apoptosis resistance in hepatocellular carcinoma ( HCC) is one of the most significant factors for hepatocarcinogenesis and tumor progression, and leads to resistance to conventional chemotherapy. It is well known that inhibitor of apoptosis proteins ( IAPs) play key roles in apoptosis resistance, it has become an important target for antitumor therapy. In this study, we examined if melatonin, the main secretory product of the pineal gland, targeted IAPs, leading to the inhibition of apoptosis resistance. To accomplish this, we first observed that four members of IAPs ( cIAP-1, cIAP-2, Survivin, and XIAP) were overexpressed in human HCC tissue. Interestingly, melatonin significantly inhibited the growth of HepG2 and SMMC-7721 cells and promoted apoptosis along with the downregulation of Survivin and XIAP, but had no effect on the expression of cIAP-1 and cIAP-2. These data suggest that the inhibition of Survivin and XIAP by melatonin may play an important part in reversing apoptosis resistance. Notably, cIAP-1, Survivin and XIAP were significantly associated with the coexpression of COX-2 in human HCC specimens. Melatonin also reduced the expression of COX-2 and inhibited AKT activation in HepG2 and SMMC-7721 cells. Inhibition of COX-2 activity with the selective inhibitor, NS398, and inhibition of AKT activation using the PI3K inhibitor, LY294002, in tumor cells confirmed that melatonin-induced apoptosis was COX-2/PI3K/AKT-dependent, suggesting that the COX-2/PI3K/AKT pathway plays a role in melatonin inhibition of IAPs. Taken together, these results suggest that melatonin overcomes apoptosis resistance by the suppressing Survivin and XIAP via the COX-2/PI3K/AKT pathway in HCC cells. [ABSTRACT FROM AUTHOR]

Hyperhomocysteinemia (Hhcy) may induce memory deficits with β-amyloid (Aβ) accumulation and tau hyperphosphorylation. Simultaneous supplement of folate and vitamin B12 partially restored the plasma homocysteine level and attenuated tau hyperphosphorylation, Aβ accumulation and memory impairments induced by Hhcy. However, folate and vitamin B12 treatment have no effects on Hhcy which has the methylenetetrahydrofolate reductase genotype mutation. In this study, we investigated the effects of simultaneous supplement of betaine on Alzheimer-like pathological changes and memory deficits in hyperhomocysteinemic rats after a 2-week induction by vena caudalis injection of homocysteine (Hcy). We found that supplementation of betaine could ameliorate the Hcy-induced memory deficits, enhance long-term potentiation ( LTP) and increase dendritic branches numbers and the density of the dendritic spines, with up-regulation of NR1, NR2A, synaptotagmin, synaptophysin, and phosphorylated synapsin I protein levels. Supplementation of betaine also attenuated the Hcy-induced tau hyperphosphorylation at multiple AD-related sites through activation protein phosphatase-2A ( PP2A) with decreased inhibitory demethylated PP2 AC at Leu309 and phosphorylated PP2 AC at Tyr307. In addition, supplementation of betaine also decreased Aβ production with decreased presenilin-1 protein levels. Our data suggest that betaine could be a promising candidate for arresting Hcy-induced AD-like pathological changes and memory deficits. [ABSTRACT FROM AUTHOR]

Aims To examine a novel strategy to enhance the survival of grafted neural stem cells ( NSCs) in stroke model. Methods Using a cell counting kit-8 ( CCK-8) and TUNEL assay to test the protective effects of p53 inhibitor, pifithrin-α ( PFT-α), on oxygen glucose deprivation ( OGD) in NSCs. We compared the effects of vehicle + NSCs and FFT-α + NSCs on the efficacy of transplantation in stroke rat model using behavioral analysis, immunohistochemistry, etc. Results Pifithrin-α increased viability and decreased apoptosis in NSCs after OGD in vitro. By in vivo studies, we showed that the best recovery of neurological function in the stroke rats and the maximum survival of grafted NSCs were found in the PFT-α + NSCs group. Twelve hours after cell transplantation, p53 was localized to the nuclei of grafted NSCs in the vehicle + NSCs group but was primarily localized to the cytoplasm in the PFT-α + NSCs group. The p53-upregulated modulator of apoptosis ( PUMA) was highly expressed among the grafted cells in the vehicle + NSCs group compared with that in the PFT-α + NSCs group. Conclusion Our results indicate that PFT-α enhances the survival of grafted NSCs through the inhibition of p53 translocation into the nucleus. [ABSTRACT FROM AUTHOR]

Endoplasmic reticulum stress-mediated cell apoptosis is implicated in the development of cancer. Melatonin induces apoptosis in hepatocellular carcinoma (HCC) in experimental studies, but the effects of melatonin on endoplasmic reticulum (ER) stress-induced apoptosis in HCC have not been tested. Differences in ER stress-induced apoptosis in human hepatoma cells and normal human hepatocyte were investigated by exposure to tunicamycin (ER stress inducer). Significant differences were observed in the rate of apoptosis between HepG2 cells (hepatoma cells) and HL-7702 cells (normal human hepatocyte cells). The expression of cyclooxygenase-2 (COX-2) was increased in HepG2 cells but not in HL-7702 cells. Furthermore, down-regulation of COX-2 expression using the COX-2 inhibitor, celecoxib, increased tunicamycin-induced apoptosis concomitant with the up-regulation of pro-apoptotic transcription factor CHOP (GADD153) and down-regulation of B-cell lymphoma 2/Bcl-2-associated X protein (Bcl-2/Bax) ratio, suggesting that inhibition of COX-2 sensitized human hepatoma cells to ER stress-induced apoptosis. Interestingly, co-treatment with tunicamycin and melatonin also decreased the expression of COX-2 and significantly increased the rate of apoptosis by elevating the levels of CHOP and reducing the Bcl-2/Bax ratio. These results demonstrate that melatonin sensitizes human hepatoma cells to ER stress-induced apoptosis by down-regulating COX-2 expression, increasing the levels of CHOP and decreasing the Bcl-2/Bax ratio. [ABSTRACT FROM AUTHOR]

There is an important inflammatory component to atherosclerosis and cardiovascular disease (CVD). It is therefore interesting that the risk of CVD is high in inflammatory diseases such as systemic lupus erythematosus (SLE). In this study, we investigated nontraditional risk factors for the development of CVD in patients with SLE.Twenty?six women (mean age 52 years) with SLE and a history of CVD were compared with 26 age?matched women with SLE and no clinical manifestations of CVD (SLE controls) and 26 age?matched healthy women (population controls). Serum levels of several novel nontraditional risk and protective factors were determined: heat?shock protein (HSP)–related factors (Hsp60, Hsp70, anti–human Hsp60, anti–human Hsp70, and anti–mycobacterial Hsp65), platelet?activating factor–acetylhydrolase (PAF?AH) activity, secretory phospholipase A2 GIIA (sPLA2), and anti–endothelial cell antibody (AECA). The intima?media thickness and the presence of plaques in the common carotid arteries were determined by B?mode ultrasound as a surrogate measure of atherosclerosis.Levels of PAF?AH, but not HSP?related factors, AECA, or sPLA2, were significantly increased in SLE cases. Only PAF?AH discriminated between SLE cases and SLE controls (P = 0.005). PAF?AH was significantly associated with low?density lipoprotein (LDL) cholesterol and total cholesterol in the SLE cases (r = 0.50, P = 0.0093 and r = 0.54, P = 0.0045), but not in either control group.The increased levels of PAF?AH in SLE cases and the association between PAF?AH and LDL cholesterol adds support to the notion that PAF?AH may promote atherothrombosis in SLE. The role of HSPs in CVD is complex, since anti?Hsp65 appears to be associated with the presence of CVD, whereas Hsp70 might protect against it. In this cross?sectional study, levels of HSP?related factors, AECA, and sPLA2 were not associated with CVD in SLE. [ABSTRACT FROM AUTHOR]

To investigate how blood lipid levels are related to disease activity, clinical characteristics, and serum levels of tumor necrosis factor α (TNFα) and its soluble type 1 and 2 receptors, sTNFR1 and sTNFR2, in systemic lupus erythematosus (SLE). Fasting blood samples were obtained from an unselected cohort of SLE patients at Karolinska Hospital (n = 208, mean ± SD age 45.7 ± 14.2 years). Disease activity was estimated using the SLE Disease Activity Measure (SLAM). Levels of circulating TNFα, sTNFR1, and sTNFR2 were determined by enzyme-linked immunosorbent assay. Blood lipid levels obtained after overnight fasting were analyzed by routine chemistry. Triglyceride (TG) levels were associated with the SLAM score (r = 0.48, P < 0.0001) and with the activities of TNFα (r = 0.29, P = 0.0001), sTNFR1 (r = 0.38, P < 0.0001), and sTNFR2 (r = 0.40, P < 0.0001). High-density lipoprotein (HDL) levels were negatively associated with the SLAM score (r = -0.27, P = 0.0003) and with the activities of TNFα (r = -0.15, P = 0.04) and sTNFR2 (r = -0.19, P = 0.01). High levels of TGs, total cholesterol, TNFα, sTNFR1, and sTNFR2 all showed close correlations with the presence of nephritis and arterial disease (P < 0.05). In multiple logistic regression models, the TNFα activity and TG levels were independent determinants (P = 0.003 for both) of active disease (SLAM score ≥7). Dyslipoproteinemia with high TG/low HDL levels correlates with disease activity in SLE, and enhanced activity in the TNFα/sTNFR system seems to be an important underlying factor. Both dyslipoproteinemia and enhanced activity of the TNFα system are closely related to cardiovascular and renal manifestations in SLE, and thus both may serve as markers of more severe disease. [ABSTRACT FROM AUTHOR]

The article presents a chemical reactions polysubstituted tetrahydro-4H-pyrido[1,2-a]pyrimidines by using acylation-hydration-michael addition process.

The purpose of the present study was to investigate the efficacy of 2 Hz transcutaneous electrical nerve stimulation (TENS) to reduce cue-induced heroin craving and the corresponding cardiovascular responses. Seventy heroin addicts with at least 1 month of abstinence were enrolled and randomly divided into two groups of 35, to receive single-trial 2 Hz TENS (TENS group) or mock TENS (mock group) during experimental procedure, respectively. They were required to express their degree of craving by visual analog scale before and after the presentation of a video-cue, and after TENS treatment, which lasted for 30 minutes. Heart rate and arterial blood pressure were simultaneously monitored in 56 cases, with 28 in each group. Results show that in mock group, video-cue induced a dramatic increase of craving score, which did not return to baseline in 150 minutes, whereas in the TENS group, 2 Hz TENS treatment produced a significant decrease of craving, reaching baseline in 90 minutes. Video-cue induced a significant increase of heart rate and systolic and diastolic blood pressure, which remained elevated for at least 60 minutes in the mock group; whereas in the TENS group, they returned to baseline immediately after the termination of TENS. These results indicate that the craving induced by a heroin-related cue can be immediately and significantly suppressed, and the cardiovascular activation totally abolished by a single-trial 2 Hz TENS for 30 minutes.