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Candida albicans biofilm infections are usually treated with azole antifungals such as fluconazole. However, the development of resistance to this drug in C. albicans biofilms is very common, especially in immunocompromised individuals. The upregulation of the sterol biosynthetic pathway gene ERG and the efflux pump genes CDR and MDR may contribute to this azole tolerance in Candida species. We hypothesize that farnesol, an endogenous quorum sensing molecule with possible antimicrobial properties which is also the precursor of ergosterols in C. albicans, may interfere with the development of fluconazole resistance in C. albicans biofilms. To test this hypothesis, MICs were compared and morphology changes were observed by confocal laser scanning microscopy (CLSM) for farnesol-treated and -untreated and fluconazole-resistant groups. The expression of possible target genes (ERG11, ERG25, ERG6, ERG5, ERG3, ERG1, MDR1, CDR1, and CDR2) in biofilms was analyzed by reverse transcription-PCR (RT-PCR) and quantitative PCR (qPCR) to investigate the molecular mechanisms of the inhibitory effects of farnesol. The results showed a decreased MIC of fluconazole and thinner biofilms for the farnesol-treated group, indicating that farnesol inhibited the development of fluconazole resistance. The sterol biosynthetic pathway may contribute to the inhibitory effects of farnesol, as the transcription levels of the ERG11, ERG25, ERG6, ERG3, and ERG1 genes decreased in the farnesol-treated group.

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In this work, benzocyclobutene‐introduced poly(silmethylene)s were synthesized by ring‐opening copolymerization of benzocyclobutene (BCB) functionalized disilacyclobutene with phenyldisilacyclobutene. The incorporation ratio of BCB was tailored by changing feeding ratio of 1,3‐dimethyl‐1,3‐dibenzocyclobutene‐1,3‐disilacyclobutane and 1,3‐dimethyl‐1,3‐diphenyl‐1,3‐disilacyclobutane, thus enabling the control of ultimate properties of cured resins. With increasing the incorporation ratios of BCB from 9.5 to 28.9 mol%, T5% of cured resins is improved from 404°C to 462°C, while the dielectric constant is decreased from 2.59 to 2.41 at 10 MHz. The excellent thermal stability and low‐dielectric performance make such thermosets potential inter‐layered or inter‐lined low‐dielectric media. Copyright © 2017 John Wiley & Sons, Ltd.

Low dielectric photopatternable materials have aroused much interest owing to their potential application as alternatives of conventional photoresists. Although a number of photosensitive groups have been established to construct photopatternable materials for many years, it is still a challenge to introduce them into polymer chains via a facile and control polymerization technique, such as living free radical polymerization. In this work, on the basis of the photoactive silaycyclobutene moiety, a new monomer, 1‐methyl‐1‐(4‐vinylphenyl) silacyclobutane (1‐MVPSCB), was synthesized and demonstrated successful to conduct atom transfer radical polymerization (ATRP). Subsequently, the copolymerization of 1‐MVPSCB with 4‐vinylbenzocyclobutene (4‐VBCB) and styrene produced a kind of benzocyclobutene/silacyclobutane double‐crosslinked polymer (BS‐DCP) with controlled benzocyclobutene/silacyclobutane ratios and low polydispersity index. Owing to the UV/thermally dual crosslinked structure, BS‐DCP possesses photapatternability, high dimensional stability and low dielectric constant (2.37 at 10 MHz). These properties make BS‐DCP a potential photoresist that could be directly used as interconnected dielectrics. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 1920–1928