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Chronic cellular stress has a profound impact on the brain, leading to degeneration and accelerated aging. Recent work has revealed the vital role of RNA modifications, and the proteins responsible for regulating them, in the stress response. In our study, we defined the role of CG14618/dTrmt10A, the Drosophila counterpart of human TRMT10A a N1-methylguanosine methyltransferase, on m6A regulation and heat stress resilience in the Drosophila brain. By m6A-IP RNA sequencing on Drosophila head tissue, we demonstrated that manipulating dTrmt10A levels indirectly regulates m6A levels on polyA + RNA. dTrmt10A exerted its influence on m6A levels on transcripts enriched for neuronal signaling and heat stress pathways, similar to the m6A methyltransferase Mettl3. Intriguingly, its impact primarily targeted 3' UTR m6A, setting it apart from the majority of Drosophila m6A-modified transcripts which display 5' UTR enrichment. Upregulation of dTrmt10A led to increased resilience to acute heat stress, decreased m6A modification on heat shock chaperones, and coincided with decreased decay of chaperone transcripts and increased translation of chaperone proteins. Overall, these findings establish a potential mechanism by which dTrmt10A regulates the acute brain stress response through m6A modification. [ABSTRACT FROM AUTHOR]

Anxiety is increasingly reported, especially in adolescent females. The etiology is largely unknown, which limits effective treatment. Layer 5 prelimbic cortex (L5PL) increases anxiety responses but undergoes adolescent synaptic pruning, raising the question of the impact of pruning on anxiety. Here we show that preventing L5PL pruning increases anxiety in response to an aversive event in adolescent and adult female mice. Spine density of Golgi-stained neurons decreased ~ 63% from puberty (~ PND35, vaginal opening) to post-puberty (PND56, P < 0.0001). Expression of α4βδ GABAA receptors (GABARs) transiently increased tenfold in L5PL at puberty (P < 0.00001), but decreased post-pubertally. Both global and local knockdown of these receptors during puberty prevented pruning, increasing spine density post-pubertally (P < 0.0001), an effect reversed by blocking NMDA receptors (NMDARs). Pubertal expression of the NMDAR-dependent spine protein kalirin7 decreased (50%, P < 0.0001), an effect prevented by α4 knock-out, suggesting that α4βδ-induced reductions in kalirin7 underlie pruning. Increased spine density due to local α4 knockdown at puberty decreased open arm time on the elevated plus maze post-pubertally (62%, P < 0.0001) in response to an aversive stimulus, suggesting that increases in L5PL synapses increase anxiety responses. These findings suggest that prelimbic synaptic pruning is necessary to limit anxiety in adulthood and may suggest novel therapies. [ABSTRACT FROM AUTHOR]

Transition metal oxides are very promising alternative anode materials for high-performance lithium-ion batteries (LIBs). However, their conversion reactions and concomitant volume expansion cause the pulverization, leading to poor cycling stability, which limit their applications. Here, we present the quasi-single-crystal NixCo3-xO4 hexagonal microtube (QNHM) composed of continuously twinned single crystal submicron-cubes as anode materials for LIBs with high energy density and long cycle life. At the current density of 0.8 A g−1, it can deliver a high discharge capacities of 1470 mAh g−1 over 100 cycles (105% of the 2nd cycle) and 590 mAh g−1 even after 1000 cycles. To better understand what underlying factors lead our QNHMs to achieve excellent electrochemical performance, a series of NixCo3-xO4 products with systematic shape evolution from spherical to polyhedral, and cubic particles as well as circular microtubes consisted of spheres and square microtubes composed of polyhedra have been synthesized. The excellent electrochemical performance of QNHMs is attributed to the unique stable quasi-single-crystal structure, which can both provide efficient electrical transport pathway and suppress the electrode pulverization. It is important to note that such quasi-single-crystal structure would be helpful to explore other high-energy lithium storage materials based on alloying or conversion reactions. [ABSTRACT FROM AUTHOR]

Novel-morphological Fe3O4 nanosheets with magnetochromatic property have been prepared by a modified solvothermal method. Such nanosheets could form one-dimension photonic crystal under an external magnetic field. The Fe3O4 nanosheets suspension could strongly diffract visible light and display varied colors with changing the intensity of the magnetic field. The photonic response is rapid, fully reversible and widely tunable in the entire visible spectrum. Excellent magnetic properties of these Fe3O4 nanosheets are exhibited with a high saturation magnetization (82.1 emu/g), low remanence (13.85 emu/g) and low coercive force (75.95 Oe). The amount of the solvent diethylene glycol (DEG) plays a key role in the formation of the sheet-shaped morphology. When the ratio of the DEG reaches 100%, the growing of the crystal plane (111) of Fe3O4 is inhibited and the sheet-like Fe3O4 crystals are formed. [ABSTRACT FROM AUTHOR]

Extensive efforts have been devoted to develop innovative synthesis strategies for nanomaterials in order to exploit the true potential of nanotechnology. However, most approaches require high temperature or high pressure to favor crystallization. Here we highlight an unconventional approach for the confined-space synthesis of the single crystal TiO2 nanowires in the atmospheric vessel at low temperature by cleverly manipulating the unique physical properties of straight-chain saturated fatty acids. Our method also applys to icosane due to its straight-chain saturated hydrocarbon structure and similar physical properties to the saturated fatty acids. Interestingly, we also found that the unsaturated fatty acids can facilitate the crystal growth, but their bent chains lead to the formation of TiO2 particle aggregates. In addition, we demonstrate the growth of TiO2 nanowires on arbitrary substrates, which are of great importance for their wider applications. We thus anticipate our presented method to be a possible starting point for non-classical crystallization strategies and be easily adapted for the fabrication of all other inorganic materials. [ABSTRACT FROM AUTHOR]

Abstract Musical training has been associated with various cognitive benefits, one of which is enhanced speech perception. However, most findings have been based on musicians taking part in ongoing music lessons and practice. This study thus sought to determine whether the musician advantage in pitch perception in the language domain extends to individuals who have ceased musical training and practice. To this end, adult active musicians (n = 22), former musicians (n = 27), and non-musicians (n = 47) were presented with sentences spoken in a native language, English, and a foreign language, French. The final words of the sentences were either prosodically congruous (spoken at normal pitch height), weakly incongruous (pitch was increased by 25%), or strongly incongruous (pitch was increased by 110%). Results of the pitch discrimination task revealed that although active musicians outperformed former musicians, former musicians outperformed non-musicians in the weakly incongruous condition. The findings suggest that the musician advantage in pitch perception in speech is retained to some extent even after musical training and practice is discontinued.

Nonhuman primates provide an important model not only for understanding human brain but also for translational research in neurological and psychiatric disorders. However, many high-resolution techniques for recording neural activity in vivo that were initially established for rodents have not been yet applied to the nonhuman primate brain. Here, we introduce a combination of two-photon targeted patching and dendritic Ca 2+ imaging to the neocortex of adult common marmoset, an invaluable primate model for neuroscience research. Using targeted patching, we show both spontaneous and sensory-evoked intracellular dynamics of visually identified neurons in the marmoset cortex. Using two-photon Ca 2+ imaging and intracellular pharmacological manipulation, we report both action-potential-associated global and synaptically-evoked NMDA (N-methyl-D-aspartate) receptor-mediated local Ca 2+ signals in dendrites and spines of the superficial-layer cortical neurons. Therefore, we demonstrate the presence of synaptic Ca 2+ signals in neuronal dendrites in living nonhuman primates. This work represents a proof-of-principle for exploring the primate brain functions in vivo by monitoring neural activity and morphology at a subcellular resolution.

Activated T cells have been shown to be able to recirculate into the thymus from the periphery. The present study was aimed to elucidate the functional consequences of thymic homing of activated T cells upon developing thymocytes and thymic epithelial cells (TEC). In the presence of activated T cells, especially CD4 + T cells, T cell development was found to be inhibited in thymic organ cultures with markedly reduced cellularity. Thymic transplantation demonstrated that the inhibitory effect was most likely due to a defective microenvironment. As the major component of the thymic stroma, the TEC compartment was severely disturbed after prolonged exposure to the activated T cells. In addition to reduced cell proliferation, TEC differentiation was heavily skewed to the mTEC lineage. Furthermore, we demonstrated that RANKL highly expressed by activated CD4 + T cells was primarily responsible for the detrimental effects. Presumably, excessive RANK signaling drove overproduction of mTECs and possibly exhaustion of epithelial progenitors, thereby facilitating the deterioration of the epithelial structures. These findings not only reveal a novel activity of activated T cells re-entering the thymus, but also provide a new perspective for understanding the mechanism underlying thymic involution.