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While circulating DNA has been extensively explored as a potential cancer biomarker, RNA potential has been overlooked so far. Here the authors present a comprehensive analysis of extracellular RNA secreted by glioblastoma cells that could prove a valuable resource for biomarker discovery and a means of intercellular communication.

Intercellular communication within complex biological and pathological systems via extracellular vesicles (EVs) and secreted factors is a highly attractive area of research. However, cell models enabling investigation of such communication in vitro are limited. Commonly utilized is the supplementation of hyper-concentrated EVs or other extracellular factors to the recipient cell cultures. This approach requires purification of the secreted complexes and is confounded by the contamination of media components. Two-chamber co-cultures of donor and recipient cells separated by a pore membrane may represent a more physiological and better-controlled system for the investigation of intercellular communication. Yet, distinct culture conditions for different neural cell types often make them incompatible for co-culturing. Here we optimized short-term co-cultures of patient-derived low-passage glioma-initiating stem cells with normal cells of the brain microenvironment, such as primary neurons, astrocytes, microglia, and brain endothelial cells. We demonstrate the culture compatibility of these cell types and internalization of glioma-derived extracellular RNA by the normal recipient cells. The presented protocols are valuable for the investigation of intercellular communication between glioma brain tumor and cells of its microenvironment, including but not limited to the EVs-mediated communication.RESEARCH IN CONTEXTCell-to-cell communication is essential in normal physiology and implicated in disease; however, experimental systems for its modeling in vitro are limited. Particularly, the investigation of communication between brain tumors and normal cells of the brain microenvironment has been challenged by the lack of adequate culture models. Here we developed co-cultures of glioma stem cells with various types of normal brain cells, including primary neurons, astrocytes, microglia, and brain endothelial cells, and demonstrated their utility for the study of intercellular communication. Detection of proposed markers in the recipient cells confirmed RNA transfer in these co-cultures.

This theoretical study is devoted to the effects of pressure and temperature on the optoelectronic properties assigned to the first lowest transition of the (D+,X) excitonic complex (exciton-ionized donor) inside a single AlAs/GaAs/AlAs spherical quantum dot. Calculations are performed within the effective mass approximation theory using the variational method. Optical absorption and refractive index as function of the degree of confinement, pressure, and temperature are investigated. Numerical calculation shows that the pressure favors the electron-hole and electron-ionized donor attractions which leads to an enhancement of the binding energy, while an increasing of the temperature tends to reduce it. Our investigations show also that the resonant peaks of the absorption coefficient and the refractive index are located in the terahertz region and they undergo a shift to higher (lower) therahertz frequencies when the pressure (temperature) increases. The opposite effects caused by temperature and pressure have great practical importance because they offer an alternative approach for the adjustment and the control of the optical frequencies resulting from the transition between the fundamental and the first excited state of exciton bound to an ionized dopant. The comparison of the optical properties of exciton, impurity and (D+,X) facilitates the experimental identification of these transitions which are often close. Our investigation shows that the optical responses of (D+,X) are located between the exciton (high energy region) and donor impurity (low energy region) peaks. The whole of these conclusions may lead to the novel light detector or source of terahertz range.

Abstract Fetal alcohol spectrum disorder (FASD) is a frequent cause of mental retardation. However, the molecular mechanisms underlying brain development defects induced by maternal alcohol consumption during pregnancy are unclear. We used normal and Hsf2‐deficient mice and cell systems to uncover a pivotal role for heat shock factor 2 (HSF2) in radial neuronal migration defects in the cortex, a hallmark of fetal alcohol exposure. Upon fetal alcohol exposure, HSF2 is essential for the triggering of HSF1 activation, which is accompanied by distinctive post‐translational modifications, and HSF2 steers the formation of atypical alcohol‐specific HSF1–HSF2 heterocomplexes. This perturbs the in vivo binding of HSF2 to heat shock elements (HSEs) in genes that control neuronal migration in normal conditions, such as p35 or the MAPs (microtubule‐associated proteins, such as Dclk1 and Dcx), and alters their expression. In the absence of HSF2, migration defects as well as alterations in gene expression are reduced. Thus, HSF2, as a sensor for alcohol stress in the fetal brain, acts as a mediator of the neuronal migration defects associated with FASD.

Innate immunity constitutes the first nonspecific immunological line of defense against infection. In this response, a variety of mechanisms are activated: the complement system, phagocytosis, and the inflammatory response. Then, adaptive immunity is activated. Major opsonization mediators during infections are immunoglobulins (Igs), the function of which is mediated through Fc receptors (FcRs). However, in addition to their role in adaptive immunity, FcRs have been shown to play a role in innate immunity by interacting directly with bacteria in the absence of their natural ligands (Igs). Additionally, it has been hypothesized that during the early phase of bacterial infection, FcRs play a protective role via innate immune functions mediated through direct recognition of bacteria, and as the infection progresses to later phases, FcRs exhibit their established function as receptors in adaptive immunity. This review provides detailed insight into the potential role of FcRs as innate immune mediators of the host defense against bacterial infection independent of opsonins. [ABSTRACT FROM AUTHOR]

Local translation at the synapse plays key roles in neuron development and activity-dependent synaptic plasticity. mRNAs are translocated from the neuronal soma to the distant synapses as compacted ribonucleoparticles referred to as RNA granules. These contain many RNA-binding proteins, including the Fragile X Mental Retardation Protein (FMRP), the absence of which results in Fragile X Syndrome, the most common inherited form of intellectual disability and the leading genetic cause of autism. Using FMRP as a tracer, we purified a specific population of RNA granules from mouse brain homogenates. Protein composition analyses revealed a strong relationship between polyribosomes and RNA granules. However, the latter have distinct architectural and structural properties, since they are detected as close compact structures as observed by electron microscopy, and converging evidence point to the possibility that these structures emerge from stalled polyribosomes. Time-lapse video microscopy indicated that single granules merge to form cargoes that are transported from the soma to distal locations. Transcriptomic analyses showed that a subset of mRNAs involved in cytoskeleton remodelling and neural development is selectively enriched in RNA granules. One third of the putative mRNA targets described for FMRP appear to be transported in granules and FMRP is more abundant in granules than in polyribosomes. This observation supports a primary role for FMRP in granules biology. Our findings open new avenues for the study of RNA granule dysfunctions in animal models of nervous system disorders, such as Fragile X syndrome.

Blue phosphorene (Blu-Pn) is a new phosphorene allotrope capable of hosting a substantial amount of sodium (Na) atoms. However, it has been reported to exhibit low electrical conductivity, chemical sensitivity, and structural stability, thus limiting its utility as an anode material for Na-ion batteries (NIBs). In this work, we introduce BC2N as a protective layer for Blu-Pn. Based on van der Waals (vdW) corrected density functional theory (DFT), we conduct a comprehensive first-principles study to explore the main electrochemical properties of the BC2N/Blu-Pn vdW heterostructure. The BC2N/Blu-Pn system exhibits a small band-gap of 0.03 eV that fades away and indicates metallic behavior upon Na adsorption. Furthermore, the binding energy of Na incorporated into the inter-layer of the BC2N/Blu-Pn system is lower (−2.03 eV) compared with those of free-standing BC2N (−1.25 eV) and Blu-Pn monolayer (−1.52 eV). Therefore, the growth of Na dendrites can be avoided. Furthermore, the migration energy barrier for the BC2N/Blu-Pn system is about 0.11 eV, indicating fast Na diffusion and excellent rate performance. Moreover, the theoretical storage capacity is 763 mA h g−1. Finally, we show that the intercalation of Na in the BC2N/Blu-Pn system has the advantage of a small average voltage of approximately 0.24 V. Besides these properties, the proposed heterostructure is based on chemical elements that are widely available and technologically established and have low atomic mass, which are all advantages for Na-ion battery applications. [ABSTRACT FROM AUTHOR]

This work investigates the transport properties of layered black phosphorus (BP) grown by the chemical vapor transport (CVT). The electrical measurements are carried out at a temperature ranging from 300 to 2 K and a magnetic field up to 16 Tesla. The CVT‐grown BP exhibits p‐type conduction with an acceptor's 14–1.2 meV activation energy. The concentration of ionized acceptors is 1.2×1017cm−3$1.2 \times {10^{17}}{\rm{c}}{{\rm{m}}^{ - 3}}$ Moreover, the Hall mobility is found to be 138 cm2V−1s−1 and 4 × 104 cm2V−1s−1, respectively, at room temperature and 2 K. This work reveals the potential of CVT synthesis as a simple, nontoxic, and cheap technique to make high‐quality BP crystals with high carrier mobility ready as a solid foundation for BP single‐crystal application. [ABSTRACT FROM AUTHOR]