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In the production of novel biological products, plasmids are often engineered into delivery vectors for target genes, which can be used directly as vaccines or as intermediate products for gene/cell therapy. Plasmid DNA exists in several topological forms such as supercoiled, linear, and open circular. As supercoiled plasmid shows the highest efficiency in transfecting eukaryotic cells, the content of supercoiled plasmids becomes an important indicator of plasmid quality. CGE is an effective analysis method for separating different topological structures of plasmids. For the purpose of providing plasmid manufacturers and regulatory agencies with an efficient and readily used tool for monitoring the quality of plasmids, this article identifies the optimal separation and detection conditions of CGE, presents a platform-based plasmid analytical method, and uses plasmid of different sizes to verify the feasibility of this method. In terms of detector, the LIF detector has obvious advantages over the ultraviolet detector in sensitivity and resolution. Using the optimal CE condition (10× gel buffer), baseline separation of different topological forms and impurities can be achieved for different plasmid sizes (5.9, 7.8, 15.4 kb). In addition, 6.5 kb plasmid was used to compare the different separation technologies such as CGE-LIF, ion exchange chromatography and agarose gel electrophoresis. The result shows that CGE-LIF can provide better resolution and quantitation accuracy than ion exchange chromatography and agarose gel electrophoresis. CGE-LIF, as a quick and convenient method to separate and quantify plasmids, has the advantages of high sensitivity, high resolution, and high quantitative accuracy. Therefore, it is ideal for analysis of plasmids with different sizes, and it can also be used as a platform method for manufacturers and regulatory agencies to monitor the purity and stability of plasmids.

Polymeric ionic liquids (PILs) have attracted considerable attention as electrolytes with high stability and mechanical durability. Light-responsive materials are enabling for a variety of future technologies owing to their remote and noninvasive manipulation, spatiotemporal control, and low environmental impact. To address this potential, responsive PIL materials based on diarylethene units were designed to undergo light-mediated conductivity changes. Key to this modulation is tuning of the cationic character of the imidazolium bridging unit upon photoswitching. Irradiation of these materials with UV light triggers a circa 70 % drop in conductivity in the solid state that can be recovered upon subsequent irradiation with visible light. This light-responsive ionic conductivity enables spatiotemporal and reversible patterning of PIL films using light. This modulation of ionic conductivity allows for the development of light-controlled electrical circuits and wearable photodetectors.

Light‐responsive color‐switching materials (LCMs) are long‐lasting hot fields. However, non‐ideal comprehensive performance (such as color contrast and retention time cannot be combined, unsatisfactory repeatability, and non‐automated coloring mode) significantly hinder their development toward high‐end products. Herein, the development of LCMs that exhibit long retention time, good color contrast, repeatability, and the property of automatic coloring is reported. The realization of this goal stems from the adoption of a bio‐inspired multi‐component collaborative step‐by‐step coloring strategy. Under this strategy, a conventional one‐step photochromic process is divided into a “light+heat” controlled multi‐step process for the fabrication of the desired LCMs. The obtained LCMs can effectively resist the long‐troubled ambient‐light interference and avoid its inherent yellow background, thereby achieving the longest retention time and good repeatability. Multiple colors are generated and ultra‐fast imaging compatible with the laser‐printing technology is also realized. The application potential of the materials in short‐term reusable identity cards, absorptive readers, billboards, and shelf labels is demonstrated. The results reported herein can potentially help in developing and designing various high‐performance, switchable materials that can be used for the production of high‐end products., High‐performance light‐driven color‐switching material (LCM) is developed exploiting the step‐controllable light‐induced proton transfer process occurring between highly sensitive photoacids and “inert” acidochromic dyes. The excellent performance of the fabricated LCM makes it a suitable candidate that can be used for the development of reusable display and erasable ink.

Sirtuin 2 (SIRT2) is a member of the sirtuin family of NAD(+) -dependent protein deacetylases. In recent years, SIRT2 inhibition has emerged as a promising treatment for neurodegenerative diseases. However, to date, there is no evidence of a specific role for SIRT2 in traumatic brain injury (TBI). We investigated the effects of SIRT2 inhibition on experimental TBI using the controlled cortical impact (CCI) injury model. Adult male mice underwent CCI or sham surgery. A selective brain-permeable SIRT2 inhibitor, AK-7, was administrated 30 min before injury. The volume of the brain edema lesion and the water content of the brain were significantly increased in mice treated with AK-7 (20 mg/kg), compared with the vehicle group, following TBI (p < 0.05 at 1 day and p < 0.05 at 3 days, respectively). Concomitantly, AK-7 administration greatly worsened neurobehavioral deficits on days 3 and 7 after CCI. Furthermore, blood-brain barrier disruption and matrix metalloproteinases (MMP)-9 activity increased following SIRT2 inhibition. AK-7 treatment increased TBI-induced microglial activation both in vivo and in vitro, accompanied by a large increase in the expression and release of inflammatory cytokines. Mechanistically, SIRT2 inhibition increased both K310 acetylation and nuclear translocation of NF-κB p65, leading to enhanced NF-κB activation and up-regulation of its target genes, including aquaporin 4 (AQP4), MMP-9, and pro-inflammatory cytokines. Together, these data demonstrate that SIRT2 inhibition exacerbates TBI by increasing NF-κB p65 acetylation and activation. Our findings provide additional evidence of an anti-inflammatory effect of SIRT2. SIRT2 is a member of the sirtuin family of NAD+-dependent protein deacetylases. Our study suggests that the SIRT2 inhibitor AK-7 exacerbates traumatic brain injury (TBI) via a potential mechanism involving increased acetylation and nuclear translocation of NF-κB p65, resulting in up-regulation of NF-κB target genes, including aquaporin 4 (AQP4), matrix metalloproteinase 9 (MMP-9), and pro-inflammatory cytokines. Our findings provide additional evidence of an anti-inflammatory effect of SIRT2.

A series of catalysts, ionic liquid-modified SBA-15 (denoted ILSBA) doped with H5PMo10V2O40 (HPMoV2) have been synthesized and characterized by XRD, FT-IR, 1H NMR, TG-DTA, and TEM. The catalyst was used for the removal of dibenzothiophene (DBT) in model oil combined with hydrogen peroxide (the oxidant) and acetonitrile (the phase-transfer agent). It was observed that the sulfur content of DBT can be reduced from 500 to 2 ppm by adjusting the amount of catalyst, the reaction temperatures and the reaction time. Besides, the catalyst activity for different sulfur compounds showed a huge difference which may be mainly affected by the electron densities of sulfur atom. Moreover, the catalyst can be recycled seven times without a significant loss in activity, which could be ascribed to the strong electrostatic interaction between ILSBA and HPMoV2. In addition, a postulated mechanism was proposed to reveal the oxidative desulfurization process.

A shape-persistent macrocycle consisting of 2,6-disubstituted aniline linked by acetylene, butadiyne, and an inner tetraethylene glycol bridge was prepared by Pd/Cu homocoupling oxidation reaction. The morphology of the resulting macrocycle was demonstrated and discussed, indicating the establishment of channels with amine functional groups inside the pores. Polarized optical microscopy (POM) observation of the macrocycle indicated the formation of liquid crystals (LCs) in the heating and cooling processes.

It is necessary to investigate the mechanisms underlying ATP release from neural cells, because extracellular ATP plays multiple important biological roles in the brain. CD38 is an ectoenzyme that consumes NAD(+) to produce cyclic ADP-ribose (cADPR), a potent agonist of ryanodine receptors. Our previous study showed that CD38 reductions led to microglial apoptosis. In this study, we used both murine microglial BV2 cells and primary microglial cultures as cellular models to test our hypothesis that basal CD38/cyclic ADP-ribose (CD38/cADPR)-dependent signaling plays a key role in ATP release, which mediates basal survival of microglia. We found that inhibition of CD38/cADPR-dependent signaling by CD38 silencing or 8-Bromo-cADPR, a ryanodine receptor antagonist, produced significant ATP release from BV2 microglia. Cx43 small interfering RNA and Cx43 hemichannel blocker 18-α-glycyrrhetinic acid completely prevented the CD38 silencing or 8-Bromo-cADPR-induced ATP release. Prevention of the ATP release could also be due to P2X7 receptor antagonists. Our study has further suggested a key role of ATP release in the microglial apoptosis induced by decreased CD38/cADPR-dependent signaling. In addition, by using primary microglial cultures, we found that 8-Bromo-cADPR also induced significant ATP release, which could be attenuated by 18-α-glycyrrhetinic acid. 8-Bromo-cADPR was also found to induce death of primary microglial cultures. In conclusion, our results have suggested novel roles of basal activation of CD38/cADPR-dependent signaling in mediating microglial functions and survival: It mediates ATP release from microglia by modulating Cx43 hemichannels, which can significantly affect microglial survival.

A series of Fe3O4-PES ultrafiltration membranes with different mass ratios of Fe3O4 and PAA were prepared from suspensions, using the phase inversion process. The suspensions consisted of polyether sulfone (PES), dimethyl formamide, polyacrylic acid (PAA), and ferrosoferric oxide (Fe3O4). The separation properties of ultrafiltration membranes with different Fe3O4/PAA mass ratio were investigated by a cross-flow experimental system. The Fe3O4/PAA mass ratio had little effect on the rejection of membranes to BSA. However, the pure water flux had a slight decline and then rised rapidly with the increase of Fe3O4/PAA mass ratio. An interesting phenomenon observed was that the Fe3O4 particles could diffuse into the nonsolvent bath during the formation of membrane, and the amount of Fe3O4 extracted into the nonsolvent bath nearly kept a constant mass ratio to PAA, even if the Fe3O4/PAA proportion was changed. The reasons of this interesting phenomenon were investigated. This result indicates that modified inorganic fillers may be used as the pore-forming agent to prepare the porous membranes like the template leaching method. At the same time, this method does not use any strong acid or base. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

Accumulating evidence has shown that microRNAs are involved in multiple processes in cancer development and progression. Here, we report that expression of miR-625 is significantly down-regulated and negatively correlated with lymph node metastasis in gastric cancer. miR-625 significantly inhibits invasion and metastasis of gastric cancer cells both in vitro and in vivo. Moreover, we identify that ILK is a direct target gene for miR-625 and knockdown of ILK has a phenocopy of overexpression of miR-625. Taken together, our findings suggest that miR-625 plays an important role in the mechanism of tumor metastasis.

Summary In many clinical studies with a survival outcome, administrative censoring occurs when follow-up ends at a prespecified date and many subjects are still alive. An additional complication in some trials is that there is noncompliance with the assigned treatment. For this setting, we study the estimation of the causal effect of treatment on survival probability up to a given time point among those subjects who would comply with the assignment to both treatment and control. We first discuss the standard instrumental variable (IV) method for survival outcomes and parametric maximum likelihood methods, and then develop an efficient plug-in nonparametric empirical maximum likelihood estimation (PNEMLE) approach. The PNEMLE method does not make any assumptions on outcome distributions, and makes use of the mixture structure in the data to gain efficiency over the standard IV method. Theoretical results of the PNEMLE are derived and the method is illustrated by an analysis of data from a breast cancer screening trial. From our limited mortality analysis with administrative censoring times 10 years into the follow-up, we find a significant benefit of screening is present after 4 years (at the 5% level) and this persists at 10 years follow-up.

Nanocrystalline anatase TiO 2 has been successfully synthesized using TiCl 4 and O 2 as precursors by atmospheric cold plasmas generated by dielectric barrier discharges (DBD) without extra heating or thermal treatment. For the TiO 2 powders synthesized by DBD plasma at an energy density of 5.9 kJ.L -1 , XRD and TEM analyses revealed that the nanocrystallite size is about 10-15 nm. Only a single crystalline structure of anatase was observed performing XRD, HRTEM and SAED measurements. It was found that the particle size decreased with increasing the discharge power, and that the chlorine contamination dramatically decreased when using high discharge power levels.

Considering temperature effects, we compare the equation of Vinet et al., the Birch equation and the K-D equation with experimental data. The results show that the Birch equation is the best.