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Abstract: A novel one-step synthesis method of FeCl3–graphite intercalation compounds (FeCl3–GICs) by an arc discharge in aqueous solution was reported for the first time. It presented a simply and controllable way to synthesize FeCl3–GICs. The structure of the stage 7 GICs was examined and characterized by X-ray diffraction. X-ray photoelectron spectroscopic study of stage 7 of FeCl3–GICs was also carried out. The change in the binding energy suggests the nature of charge transfer and lowering of Fermi level as has been reported previously for other acceptor intercalation compounds. [Copyright &y& Elsevier]

Why some tumors remain indolent and others progress to clinical relevance remains a major unanswered question in cancer biology. IFN signaling in nascent tumors, mediated by STAT1, is a critical step through which the surveilling immune system can recognize and destroy developing tumors. In this study, we have identified an interaction between the progesterone receptor (PR) and STAT1 in breast cancer cells. This interaction inhibited efficient IFN-induced STAT1 phosphorylation, as we observed a decrease in phospho-STAT1 in response to IFN treatment in PR-positive breast cancer cell lines. This phenotype was further potentiated in the presence of PR ligand. In human breast cancer samples, PR-positive tumors exhibited lower levels of phospho-STAT1 as compared with their PR-negative counterparts, indicating that this phenotype translates to human tumors. Breast cancer cells lacking PR exhibited higher levels of IFN-stimulated gene (ISG) RNA, the transcriptional end point of IFN activation, indicating that unliganded PR alone could decrease transcription of ISGs. Moreover, the absence of PR led to increased recruitment of STAT1, STAT2, and IRF9 (key transcription factors necessary for ISG transcription) to ISG promoters. These data indicate that PR, both in the presence and absence of ligand, attenuates IFN-induced STAT1 signaling, culminating in significantly abrogated activation of genes transcribed in response to IFNs. PR-positive tumors may use downregulation of STAT1-mediated IFN signaling to escape immune surveillance, leading to the development of clinically relevant tumors. Selective immune evasion of PR-positive tumors may be one explanation as to why over 65% of breast cancers are PR positive at the time of diagnosis. [ABSTRACT FROM AUTHOR]

Abstract: Theoretical calculations via a transfer matrix method (TMM) were performed to investigate the possibility of fullerene/AlN multilayer films acting as one-dimensional (1D) photonic band gap (PBG) crystals. The response within and out of the periodic plane of (C60, C70)/AlN multilayers was studied. (C60, C70)/AlN multilayer films presented incomplete PBG behavior in UV region. C60/AlN multilayers with two pairs of 49nm-C60 and 21nm-AlN layers exhibited a high reflectivity of 90.4% at a wavelength of about 200nm. As a consequence, this photonic crystal may be important for achieving materials with an incomplete band gap in the UV region. [Copyright &y& Elsevier]