Reaction of coal with 1,2,3,4-tetrahydroquinoline in a perfluorocarbon medium

Three very different coals show similar behaviour when heated with low concentrations of 1,2,3,4-tetrahydroquinoline (THQ : COAL = 0.2) at 250°C in a perfluorocarbon liquid. The coals all approach 33–35 % ultimate solubility (measured in pyridine) at similar rates, with little incorporation of THQ into the coal. This transformation is attributed to a low-temperature chemical reaction between THQ and coal. Appreciable coal conversion is only observed in media in which organic molecules have limited solubility, such as perfluorocarbon liquids and water. Under similar conditions, tetralin and a variety of amines other than THQ do not effect similar coal transformations. Among model compounds, consisting of various linkages connecting phenyl groups, only disulphide and ester linkages were observed to react under conditions of the coal transformation. A poly(phenyl ester)polymer, however, was found not to react. Substituents on the phenyl groups may be required to activate bonds for reaction with THQ under the conditions of this experiment.     

MicroRNA 3928 Suppresses Glioblastoma through Downregulation of Several Oncogenes and Upregulation of p53

Glioblastoma (GBM) is the most frequent and lethal primary malignant brain tumor. Despite decades of research, therapeutic advances that significantly prolong life are non-existent. In recent years, microRNAs (miRNAs) have been a focus of study in the pathobiology of cancer because of their ability to simultaneously regulate multiple genes. The aim of this study was to determine the functional and mechanistic effects of miR-3928 in GBM both in vitro and in vivo. To the best of our knowledge, this is the first article investigating the role of miR-3928 in GBM. We measured endogenous miR-3928 expression levels in a panel of patient-derived GBM tissue samples and cell lines. We found that GBM tissue samples and cell lines express lower levels of miR-3928 than normal brain cortex and astrocytes, respectively. Therefore, we hypothesized that miR-3928 is a tumor suppressive microRNA. We verified this hypothesis by showing that exogenous expression of miR-3928 has a strong inhibitory effect on both cell growth and invasiveness of GBM cells. Stable ex vivo overexpression of miR-3928 in GBM cells led to a reduction in tumor size in nude mice xenografts. We identified many targets (MDM2, CD44, DDX3X, HMGA2, CCND1, BRAF, ATOH8, and BMI1) of miR-3928. Interestingly, inhibition of the oncogene MDM2 also led to an upregulation of wild-type p53 expression and phosphorylation. In conclusion, we find that miR-3928, through the downregulation of several oncogenes and upregulation and activation of wild-type p53, is a strong tumor suppressor in GBM. Furthermore, the fact that miR-3928 can target many important dysregulated proteins in GBM suggests it might be a “master” regulatory microRNA that could be therapeutically exploited.     

EMSCs Build an All‐in‐One Niche via Cell–Cell Lipid Raft Assembly for Promoted Neuronal but Suppressed Astroglial Differentiation of Neural Stem Cells

The therapeutic efficiency of allogenic/intrinsic neural stem cells (NSCs) after spinal cord injury is severely compromised because the hostile niche at the lesion site incurs massive astroglial but not neuronal differentiation of NSCs. Although many attempts are made to reconstruct a permissive niche for nerve regeneration, solely using a living cell material to build an all‐in‐one, multifunctional, permissive niche for promoting neuronal while inhibiting astroglial differentiation of NSCs is not reported. Here, ectomesenchymal stem cells (EMSCs) are reported to serve as a living, smart material that creates a permissive, all‐in‐one niche which provides neurotrophic factors, extracellular matrix molecules, cell–cell contact, and favorable substrate stiffness for directing NSC differentiation. Interestingly, in this all‐in‐one niche, a corresponding all‐in‐one signal‐sensing platform is assembled through recruiting various niche signaling molecules into lipid rafts for promoting neuronal differentiation of NSCs, and meanwhile, inhibiting astrocyte overproliferation through the connexin43/YAP/14‐3‐3θ pathway. In vivo studies confirm that EMSCs can promote intrinsic NSC neuronal differentiation and domesticating astrocyte behaviors for nerve regeneration. Collectively, this study represents an all‐in‐one niche created by a single‐cell material—EMSCs for directing NSC differentiation.     

Thermal fluxes in a generator of low temperature plasma with a divergent channel of the outlet electrode

A short review is presented of experimental results concerning distribution of heat fluxes over the length of a generator of low temperature plasma (plasmatron). Comparative analysis is given of the operation of plasma generators with a divergent channel of the outlet electrode against plasma generators with a cylindrical channel of constant cross section. Experimental studies were performed on a specially created facility consisting of four plasma generators with sectioned and continuous outlet electrodes and automated measuring system.