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Propofol has become a microtubule‐stabilizing drug for prostate cancer (PC) therapy, but propofol resistance impairs the therapeutic effect. This study aimed to explore the regulatory mechanism of propofol in the pathogenesis of PC through mechanisms involving N6‐methyladenosine (m6A) modification. The changes in PC cell malignancy were evaluated by means of transwell, cell counting kit 8 (CCK‐8), western blotting and tumour xenograft model assays. Long noncoding RNA TRHDE‐AS1 and m6A methyltransferase METTL14 expression levels were determined via reverse transcription quantitative polymerase chain reaction (RT‐qPCR). The m6A modification of TRHDE‐AS1 which was mediated by METTL14 was confirmed by conducting methylated RNA immunoprecipitation (MeRIP) assay. We observed that propofol (200 μM) inhibited PC cell malignancy in vivo and in vitro, elucidating that it impaired cell proliferation, migration and tumour growth but induced apoptosis. TRHDE‐AS1 expression was observed to be lower in PC cells and tissues, and propofol induced TRHDE‐AS1 upregulation in PC cells. Propofol was capable of reversing the tumour‐promoting effect of TRHDE‐AS1 knockdown in PC cells. Additionally, METTL14 was upstream of TRHDE‐AS1 to induce m6A modification of TRHDE‐AS1 in PC cells. Collectively, our results show that propofol prevents PC progression by upregulating TRHDE‐AS1 expression and METTL14 is involved in the m6A modification of TRHDE‐AS1. These findings suggest that TRHDE‐AS1 may be a potential therapeutic target for the improvement of propofol's therapeutic effect. [ABSTRACT FROM AUTHOR]

Hydroxy‐terminated polybutadiene (HTPB) was grafted onto nanosilica via two steps, and then melt extruded with PET and transition metal catalyst. Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA) results showed that HTPB successfully bridged to the surface of nanosilica through toluene‐2,4‐diisocyanate (TDI), and the grafting amount of HTPB accounted for about 11.2% of the total mass of nanosilica. The PET composite samples were also uniaxially stretched into films. Tensile results showed that the tensile strength of composite films was generally higher than that of composite sheets, especially the tensile strength of PET/SiO2‐HTPB composite film reached 139.8 MPa. After uniaxial stretching, the crystallinity of all films were significantly improved, and fillers accelerated the crystallization rate of PET, which greatly improved the crystallinity of composite materials, thereby contributing to the improvement of the oxygen barrier performance of composite materials. After adding the catalyst, the PET/SiO2‐HTPB/Co composite film has the lowest oxygen permeability coefficient of 1.05 × 10−15 (cm3·cm/cm2·s·pa), which was 87.6% lower than that of pure PET sheet. SEM showed that the compatibility between filler and matrix was improved. This study demonstrated that nanosilica grafted with HTPB played a synergistic role in improving the crystallinity of materials and exerting the active oxygen scavenging of HTPB, and uniaxial stretching was helpful for improving the comprehensive properties of composites. [ABSTRACT FROM AUTHOR]

The synthesis of hybrid star-shaped polymers was carried out by atom transfer radical polymerization of n-butyl acrylate from a well-defined multifunctional titanium-oxo-cluster initiator. Conditions were identified to prevent possible side reactions among monomer, polymer, and the titanium-oxo-cluster ligands. Polymerizations provided linear first-order kinetics and the evolution of the experimental molecular weight is also linear with the conversion. 1H DOSY NMR and cleavage of the polymeric branches from the multifunctional initiator by hydrolysis were used to (i) prove the star-shaped structure of the polymer, and (ii) demonstrate that the shoulder observed on size exclusion chromatograms is not due to a noncontrolled polymerization but to ungrafting of polymeric branches during analysis. Rheological properties of the hybrid star-shaped poly( n-butyl acrylate) were studied in the linear regime and show that the Ti-oxo-cluster not only increases significantly the viscosity of the polymer relative to its ungrafted arm but has a rheological signature which is qualitatively different from that of stars with organic cores suggesting that the Ti cluster reduces significantly the molecular mobility of the star. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 [ABSTRACT FROM AUTHOR]

The article discusses the results of a study on the effect of multiwalled carbon nanotubes (MWNT) on the crystallization mechanism of poly(ethylene terephthalate) (PET) composites. The homogeneous dispersion state of MWNT as a heterogeneous nucleating agent enhanced the crystallization and nucleation efficiency of PET. The MWNT played a role as a nuclei located in the center of PET spherulites. The molecular weight of PET did not change after nucleation of PET through particle effect.