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Abstract: Ion mobility spectrometry (IMS) is a very fast, highly sensitive, and inexpensive technique, it permits efficient monitoring of volatile organic compounds like alcohols. In this article, positive ion mobility spectra for six alcohol organic compounds have been systematically studied for the first time using a high-resolution IMS apparatus equipped with a discharge ionization source. Utilizing protonated water cluster ions (H2O)nH+ as the reactant ions and clean air as the drift gas, alcohol organic compounds, ethanol, 1-propanol, 2-propanol, 1-butanol, 1-pentanol and 2-octanol, all exhibit product ion characteristic peaks in their respective ion mobility spectrometry, that is a result of proton transfer reactions between the alcohols and reaction ions (H2O)nH+. The mixture of these alcohols, including two isomers, has been detected, and the results showed that they could be distinguished effectively in the ion mobility spectrum. The reduced mobility values have been determined, which are in very well agreement with the traditional 63Ni-IMS experimental values. The exponential dilution method was used to calibrate the alcohol concentrations, and a detection limit available for the alcohols is in order of magnitude of a few ng/L. [Copyright &y& Elsevier]

Glioblastoma (GBM) is a highly aggressive brain tumor. During screening work, we found a new compound named phragmunis A (PGA), which is derived from the fruitbody of Trogia venenata , exhibits a potential cytotoxic effect on patient-derived recurrent GBM cells and temozolomide (TMZ)-resistant cell lines. The present study was designed to investigate the potential molecular mechanism of the anti-glioma effects of PGA in vitro and in vivo. Studies investigating the mechanism revealed that PGA diminished the binding efficiency of ETS family of transcription factor (ELK1) and Serum response factor (SRF), and suppressed ELK1-SRF complex-dependent transcription, which decreased the transcriptional levels of downstream genes Early growth response protein 1 (EGR1)-Polycomb ring finger (BMI1), thus inducing the imbalanced regulation between Myeloid cell leukaemia-1 (MCL1) and F-Box and WD repeat domain containing 7 (FBXW7). Finally, orthotopic xenograft models were established to confirm the anti-glioma effect of PGA on tumour growth. We showed, for the first time, that the cytotoxic effects of PGA occurred by inducing MCL1 inhibition and FBXW7 activation by blocking ELK1-SRF complex-dependent transcription. The blockage of ELK1-mediated transcription resulted in the suppression of EGR1-BMI1, which led to the upregulation of FBXW7 expression and downregulation of MCL1. These findings suggested that PGA could be a therapeutic drug candidate for the treatment of recurrent GBM by targeting the ELK1-SRF complex. [Display omitted] • Phragmunis A (PGA) is a new compound isolated from the fruitbody of Trogia venenata. • PGA could overcome temozolomide resistance and be a drug candidate for the treatment of GBM. • PGA could suppress the binding efficiency of ELK1-SRF and the complex-dependent transcription. • PGA could break the feedback between MCL1 and FBXW7 via inhibition of EGR1-BMI1. [ABSTRACT FROM AUTHOR]

Background: Glioblastoma multiforme (GBM) is the most frequent, lethal and aggressive tumour of the central nervous system in adults. The discovery of novel anti-GBM agents based on the isocitrate dehydrogenase (IDH) mutant phenotypes and classifications have attracted comprehensive attention.Purpose: Diterpenoids are a class of naturally occurring 20-carbon isoprenoid compounds, and have previously been shown to possess high cytotoxicity for a variety of human tumours in many scientific reports. In the present study, 31 cassane diterpenoids of four types, namely, butanolide lactone cassane diterpenoids (I) (1-10), tricyclic cassane diterpenoids (II) (11-15), polyoxybutanolide lactone cassane diterpenoids (III) (16-23), and fused furan ring cassane diterpenoids (IV) (24-31), were tested for their anti-glioblastoma activity and mechanism underlying based on IDH1 mutant phenotypes of primary GBM cell cultures and human oligodendroglioma (HOG) cell lines.Results: We confirmed that tricyclic-type (II) and compound 13 (Caesalpin A, CSA) showed the best anti-neoplastic potencies in IDH1 mutant glioma cells compared with the other types and compounds. Furthermore, the structure-relationship analysis indicated that the carbonyl group at C-12 and an α, β-unsaturated ketone unit fundamentally contributed to enhancing the anti-glioma activity. Studies investigating the mechanism demonstrated that CSA induced oxidative stress via causing glutathione reduction and NOS activation by negatively regulating glutaminase (GLS), which proved to be highly dependent on IDH mutant type glioblastoma. Finally, GLS overexpression reversed the CSA-induced anti-glioma effects in vitro and in vivo, which indicated that the reduction of GLS contributed to the CSA-induced proliferation inhibition and apoptosis in HOG-IDH1-mu cells.Conclusion: Therefore, the present results demonstrated that compared with other diterpenoids, tricyclic-type diterpenoids could be a targeted drug candidate for the treatment of secondary IDH1 mutant type glioblastoma through negatively regulating GLS. [ABSTRACT FROM AUTHOR]

Abstract: The selection of carrier transporting layer in polymer solar cells is an important issue because the nature and direction of carrier transport can be manipulated by inserting different functional layers in the device structure. In this work, we report a very efficient inverted polymer solar cell (PSC) system based on regioregular poly(3-hexylthiophene) and a n-type acceptor, bis-indene[C60]. With a pair of metal oxides and the insertion of TiO2 nanorods electron collecting layer between the ZnO thin film and the active layer, the device efficiency can be greatly improved. The contact area between the active layer and the electron collecting layer, as well as the thickness of active layer, can be increased with the incorporation of TiO2 nanorods. As a result, photocurrent can be enhanced due to more absorption of light and more charge separation interface. In addition, the larger contact area and the crystalline TiO2 nanorods provide a more efficient transporting route for the carriers to the cathode. The most efficient device demonstrated shows a high power conversion efficiency of 5.6% with the inverted structure. [Copyright &y& Elsevier]