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Abstract Individuals’ continuous success in competitive interactions with conspecifics strongly affects their social hierarchy. Medial prefrontal cortex (mPFC) is the key brain region mediating both social competition and hierarchy. However, the molecular regulatory mechanisms underlying the neural ensemble in the mPFC remains unclear. Here, we demonstrate that in excitatory neurons of prelimbic cortex (PL), lncRNA Sera remodels the utilization of Pkm Exon9 and Exon10, resulting in a decrease in the Pkm1/2 ratio in highly competitive mice. By employing a tet-on/off system, we disrupt or rebuild the normal Pkm1/2 ratio by controlling the expression of Pkm2 in PL excitatory neurons. We find that long-term Pkm2 modulation induces timely competition alteration and hysteretic rank change, through phosphorylating the Ser845 site of GluA1. Together, this study uncovers a crucial role of lncRNA Sera/Pkm2 pathway in the transition of social competition to rank by remodeling neural ensemble in mPFC.

Repetitive traumatic brain injury impacts adult neurogenesis in the hippocampal dentate gyrus, leading to long-term cognitive impairment. However, the mechanism underlying this neurogenesis impairment remains unknown. In this study, we established a male mouse model of repetitive traumatic brain injury and performed long-term evaluation of neurogenesis of the hippocampal dentate gyrus after repetitive traumatic brain injury. Our results showed that repetitive traumatic brain injury inhibited neural stem cell proliferation and development, delayed neuronal maturation, and reduced the complexity of neuronal dendrites and spines. Mice with repetitive traumatic brain injuryalso showed deficits in spatial memory retrieval. Moreover, following repetitive traumatic brain injury, neuroinflammation was enhanced in the neurogenesis microenvironment where C1q levels were increased, C1q binding protein levels were decreased, and canonical Wnt/β-catenin signaling was downregulated. An inhibitor of C1 reversed the long-term impairment of neurogenesis induced by repetitive traumatic brain injury and improved neurological function. These findings suggest that repetitive traumatic brain injury–induced C1-related inflammation impairs long-term neurogenesis in the dentate gyrus and contributes to spatial memory retrieval dysfunction.

Minimizing toxicity of herpes simplex virus 1 (HSV) based tools for anterograde tracing is important for functional studies. Here the authors generate an anterograde monosynaptic tracer system based on HSV amplicon, which shows fast tracing, bright labeling, low toxicity, input-defined postsynaptic neurons’ anterograde monosynaptic tracing feature, and has potential for functional mapping.

The investigation of brain networks and neural circuits involves the crucial aspects of observing and modulating neurophysiological activity. Recently, opto-electrodes have emerged as an efficient tool for electrophysiological recording and optogenetic stimulation, which has greatly facilitated the analysis of neural coding. However, implantation and electrode weight control have posed significant challenges in achieving long-term and multi-regional brain recording and stimulation. To address this issue, we have developed a mold and custom-printed circuit board-based opto-electrode. We report successful opto-electrode placement and high-quality electrophysiological recordings from the default mode network (DMN) of the mouse brain. This novel opto-electrode facilitates synchronous recording and stimulation in multiple brain regions and holds promise for advancing future research on neural circuits and networks.

Abstract Dynamic change of mitochondrial morphology and distribution along neuronal branches are essential for neural circuitry formation and synaptic efficacy. However, the underlying mechanism remains elusive. We show here that Pink1 knockout (KO) mice display defective dendritic spine maturation, reduced axonal synaptic vesicles, abnormal synaptic connection, and attenuated long-term synaptic potentiation (LTP). Drp1 activation via S616 phosphorylation rescues deficits of spine maturation in Pink1 KO neurons. Notably, mice harboring a knockin (KI) phosphor-null Drp1 S616A recapitulate spine immaturity and synaptic abnormality identified in Pink1 KO mice. Chemical LTP (cLTP) induces Drp1S616 phosphorylation in a PINK1-dependent manner. Moreover, phosphor-mimetic Drp1S616D restores reduced dendritic spine localization of mitochondria in Pink1 KO neurons. Together, this study provides the first in vivo evidence of functional regulation of Drp1 by phosphorylation and suggests that PINK1-Drp1S616 phosphorylation coupling is essential for convergence between mitochondrial dynamics and neural circuitry formation and refinement.

Abstract Background Viral tracers are important tools for mapping brain connectomes. The feature of predominant anterograde transneuronal transmission offers herpes simplex virus-1 (HSV-1) strain H129 (HSV1-H129) as a promising candidate to be developed as anterograde viral tracers. In our earlier studies, we developed H129-derived anterograde polysynaptic tracers and TK deficient (H129-dTK) monosynaptic tracers. However, their broad application is limited by some intrinsic drawbacks of the H129-dTK tracers, such as low labeling intensity due to TK deficiency and potential retrograde labeling caused by axon terminal invasion. The glycoprotein K (gK) of HSV-1 plays important roles in virus entry, egress, and virus-induced cell fusion. Its deficiency severely disables virus egress and spread, while only slightly limits viral genome replication and expression of viral proteins. Therefore, we created a novel H129-derived anterograde monosynaptic tracer (H129-dgK) by targeting gK, which overcomes the limitations of H129-dTK. Methods Using our established platform and pipeline for developing viral tracers, we generated a novel tracer by deleting the gK gene from the H129-G4. The gK-deleted virus (H129-dgK-G4) was reconstituted and propagated in the Vero cell expressing wildtype H129 gK (gKwt) or the mutant gK (gKmut, A40V, C82S, M223I, L224V, V309M), respectively. Then the obtained viral tracers of gKmut pseudotyped and gKwt coated H129-dgK-G4 were tested in vitro and in vivo to characterize their tracing properties. Results H129-dgK-G4 expresses high levels of fluorescent proteins, eliminating the requirement of immunostaining for imaging detection. Compared to the TK deficient monosynaptic tracer H129-dTK-G4, H129-dgK-G4 labeled neurons with 1.76-fold stronger fluorescence intensity, and visualized 2.00-fold more postsynaptic neurons in the downstream brain regions. gKmut pseudotyping leads to a 77% decrease in retrograde labeling by reducing axon terminal invasion, and thus dramatically improves the anterograde-specific tracing of H129-dgK-G4. In addition, assisted by the AAV helper trans-complementarily expressing gKwt, H129-dgK-G4 allows for mapping monosynaptic connections and quantifying the circuit connectivity difference in the Alzheimer’s disease and control mouse brains. Conclusions gKmut pseudotyped H129-dgK-G4, a novel anterograde monosynaptic tracer, overcomes the limitations of H129-dTK tracers, and demonstrates desirable features of strong labeling intensity, high tracing efficiency, and improved anterograde specificity.

Abstract The third isoform of the Na+–Ca2+ exchanger (NCX3) is crucial for a physiological fine-tuning of the Ca2+ fluxes in excitable tissues. In this view, the NCX3 accounts for the aberrant Ca2+ influx seen during neuronal excitotoxicity, such as in Alzheimer’s disease (AD). However, little is known about NCX3 regulation and functional properties. Withania somnifera (L.) Dunal (W. somnifera), a traditional indigenous plant widely recognized for having numerous medicinal values, was undertaken to determine its potential therapeutic benefit against aggregated Aβ1–42-induced NCX3 dysregulation and the thereof cognition impairment in 5xFAD mice. The undertaken sourced dried roots of authenticated W. somnifera physicochemical compositional tests satisfied standards of pharmacognostic quality, and further phytochemical analysis of the roots methanol extract revealed the roots constitute several antioxidants. Following an intra-gastric gavage administration of synthesized W. somnifera roots methanolic extract from postnatal day 30 (P30) to P75, in vivo cognitional studies and then neurochemical examinations of the NCX3 expression level, Aβ plaque deposition, and antioxidant activities in the AD-associated brain regions of 4-month-old 5xFAD mice suggests that the oxidative stress normalizing effects of W. somnifera constituents, operating on the NCX3, may have a therapeutic role in the improvement of cognition in AD.

Abstract Background Aldh1a1 neurons are a subtype of gamma-aminobutyric acid (GABA) inhibitory neurons that use Aldh1a1 rather than glutamate decarboxylase (GAD) as an enzyme for synthesizing GABA transmitters. However, the behaviors and circuits of this newly identified subtype of inhibitory interneurons remain unknown. Methods We generated a mutant mouse line in which cyclization recombination enzyme (CRE) was expressed under the control of the Aldh1a1 promotor (Aldh1a1-CRE mice). Using this mutant strain of mice together with the heterozygous male Alzheimer’s disease (AD) related model mice (APPswe/PSEN1dE9, or AD mice) and a genetically modified retrograde and anterograde synaptic tracing strategy, we have studied a specific synaptic circuit of Aldh1a1 neurons with system-level function and disease progression in AD mice. Results We demonstrate that Aldh1a1 neurons encode delay of gratification that measures self-control skills in decision making by projecting inhibitory synapses directly onto excitatory glutamate neurons in the intermediate lateral septum (EGNIS) and receiving synaptic inputs from layer 5b pyramidal neurons in the medial prefrontal cortex (L5PN). L5PN → Aldh1a1 synaptic transmission undergoes long-term potentiation (LTP). Pathway specific inhibition by either genetic silencing presynaptic terminals or antagonizing postsynaptic receptors impairs delay of gratification, resulting in the impulsive behaviors. Further studies show that reconstitution of Aldh1a1-deficient neurons with the expression of exogenous Aldh1a1 (eAldh1a1) restores Aldh1a1 → EGNIS synaptic transmission and rescues the impulsive behaviors in AD mice. Conclusions These results not only identify a specific function and circuit of Aldh1a1 neurons but also provide a cellular point of entry to an important but understudied synaptic mechanism for the induction of impulsive behaviors at an early stage of AD.

Accumulating evidence suggests that gut microbiota as a critical mediator of gut-brain axis plays an important role in human health. Altered gut microbial profiles have been implicated in increasing the vulnerability of psychiatric disorders, such as autism, depression, and schizophrenia. However, the cellular and molecular mechanisms underlying the association remain unknown. Here, we modified the gut microbiome with antibiotics in newborn mice, and found that gut microbial alteration induced behavioral impairment by decreasing adult neurogenesis and long-term potentiation of synaptic transmission, and altering the gene expression profile in hippocampus. Reconstitution with normal gut flora produced therapeutic effects against both adult neurogenesis and behavioral deficits in the dysbiosis mice. Furthermore, our results show that circulating metabolites changes mediate the effect of gut dysbiosis on hippocampal plasticity and behavior outcomes. Elevating the serum 4-methylphenol, a small aromatic metabolite produced by gut bacteria, was found to induce autism spectrum disorder (ASD)-like behavior impairment and hippocampal dysfunction. Together our finding demonstrates that early-life gut dysbiosis and its correlated metabolites change contribute to hippocampal dysfunction and behavior impairment, hence highlight the potential microbiome-mediated therapies for treating psychiatric disorders.

Cholinergic neurons in the basal forebrain constitute a major source of cholinergic inputs to the forebrain, modulate diverse functions including sensory processing, memory and attention, and are vulnerable to Alzheimer's disease (AD). Recently, we classified cholinergic neurons into two distinct subpopulations; calbindin D28K-expressing (D28K+) versus D28K-lacking (D28K−) neurons. Yet, which of these two cholinergic subpopulations are selectively degenerated in AD and the molecular mechanisms underlying this selective degeneration remain unknown. Here, we reported a discovery that D28K+ neurons are selectively degenerated and this degeneration induces anxiety-like behaviors in the early stage of AD. Neuronal type specific deletion of NRADD effectively rescues D28K+ neuronal degeneration, whereas genetic introduction of exogenous NRADD causes D28K− neuronal loss. This gain- and loss-of-function study reveals a subtype specific degeneration of cholinergic neurons in the disease progression of AD and hence warrants a novel molecular target for AD therapy.

Abstract Background Annexin A1 (ANXA1) exerts anti-nociceptive effect through ANXA1 receptor formyl peptide receptor 2 (FPR2/ALX (receptor for lipoxin A4), FPR2) at the dorsal root ganglia (DRG) level. However, the mechanisms remain elucidated. By using radiant heat, hot/cold plate, tail flick, von Frey, and Randall-Selitto tests to detect nociception in intact and chemical (capsaicin, menthol, mustard oil, formalin or CFA) injected AnxA1 conditional knockout (AnxA1 −/−) mice, applying calcium imaging and patch clamp recordings in cultured DRG neurons to measure neuronal excitability, conducting immunofluorescence and western blotting to detect the protein levels of TRPV1, FPR2 and its downstream molecules, and performing double immunofluorescence and co-immunoprecipitation to investigate the interaction between Calmodulin (CaM) and TRPV1; we aim to uncover the molecular and cellular mechanisms of ANXA1’s role in antinociception. Results AnxA1 −/− mice exhibited significant sensitivity to noxious heat (mean ± SD, 6.2 ± 1.0 s vs. 9.9 ± 1.6 s in Hargreaves test; 13.6 ± 1.5 s vs. 19.0 ± 1.9 s in hot plate test; n = 8; P

H doping can enhance the performance of ZnO thin-film transistors (TFTs) to a certain extent, and the design of double active layers is an effective way to further improve a device’s performance. However, there are few studies on the combination of these two strategies. We fabricated TFTs with ZnO:H (4 nm)/ZnO (20 nm) double active layers by magnetron sputtering at room temperature, and studied the effect of the hydrogen flow ratio on the devices’ performance. ZnO:H/ZnO-TFT has the best overall performance when H2/(Ar + H2) = 0.13% with a mobility of 12.10 cm2/Vs, an on/off current ratio of 2.32 × 107, a subthreshold swing of 0.67 V/Dec, and a threshold voltage of 1.68 V, which is significantly better than the performance of single active layer ZnO:H-TFTs. This exhibits that the transport mechanism of carriers in double active layer devices is more complicated. On one hand, increasing the hydrogen flow ratio can more effectively suppress the oxygen-related defect states, thus reducing the carrier scattering and increasing the carrier concentration. On the other hand, the energy band analysis shows that electrons accumulate at the interface of the ZnO layer close to the ZnO:H layer, providing an additional path for carrier transport. Our research exhibits that the combination of a simple hydrogen doping process and double active layer construction can achieve the fabrication of high-performance ZnO-based TFTs, and that the whole room temperature process also provides important reference value for the subsequent development of flexible devices.

Congenital cytomegalovirus (cCMV) infection is the leading infectious cause of neurodevelopmental disorders. However, the neuropathogenesis remains largely elusive due to a lack of informative animal models. In this study, we developed a congenital murine CMV (cMCMV) infection mouse model with high survival rate and long survival period that allowed long-term follow-up study of neurodevelopmental disorders. This model involves in utero intracranial injection and mimics many reported clinical manifestations of cCMV infection in infants, including growth restriction, hearing loss, and impaired cognitive and learning-memory abilities. We observed that abnormalities in MRI/CT neuroimaging were consistent with brain hemorrhage and loss of brain parenchyma, which was confirmed by pathological analysis. Neuropathological findings included ventriculomegaly and cortical atrophy associated with impaired proliferation and migration of neural progenitor cells in the developing brain at both embryonic and postnatal stages. Robust inflammatory responses during infection were shown by elevated inflammatory cytokine levels, leukocyte infiltration, and activation of microglia and astrocytes in the brain. Pathological analyses and CT neuroimaging revealed brain calcifications induced by cMCMV infection and cell death via pyroptosis. Furthermore, antiviral treatment with ganciclovir significantly improved neurological functions and mitigated brain damage as shown by CT neuroimaging. These results demonstrate that this model is suitable for investigation of mechanisms of infection-induced brain damage and long-term studies of neurodevelopmental disorders, including the development of interventions to limit CNS damage associated with cCMV infection.

Several micro RNAs have been shown to be deregulated in brain tissue or sera from individuals with Alzheimer’s disease and in AD mouse models. The authors show that miR-135a-5p is downregulated in excitatory pyramidal neurons from AD mice and that dysfunction of miR-135a-5p/Rock2/Add1 results in memory/synaptic disorder in AD.

Abstract To further improve the performance of all-inkjet-printing ZnO UV photodetector and maintain the advantages of inkjet printing technology, the inkjet printing Ag nanoparticles (NPs) were deposited on the inkjet printing ZnO UV photodetector for the first time. The inkjet printing Ag NPs can passivate the surface defects of ZnO and work as surface plasmons from the characterization of photoluminescence (PL), X-ray photoelectron spectroscopy (XPS), and finite difference time domain method (FDTD) simulation. The normalized detectivity (D *) of the Ag NP-modified detector reaches to 1.45 × 1010 Jones at 0.715 mW incident light power, which is higher than that of 5.72 × 109 Jones of the bare ZnO photodetector. The power-law relationship between the photocurrent and the incident light power of the Ag NP-modified ZnO detector is I pc ∝ P 2.34, which means the photocurrent is highly sensitive to the change of incident light power.

Presently, the treatment options for ischemic stroke (IS) are limited due to the complicated pathological process of the disease. Chuanxiong Rhizome (CR), also known as Conioselinum anthriscoides “Chuanxiong” (rhizome), is the most widely used traditional Chinese medicine for treating stroke. This study aimed to uncover the key phytochemicals and biological functions of CR against IS through a network pharmacology approach combining with IS pathophysiology analysis. We employed permanent unilateral common carotid artery ligation to construct a mouse model of global cerebral ischemia and found that cerebral ischemia injuries were improved after 7 days of gavage treatment of CR (1,300 mg/kg/day). CR exerts protective effects on neurons mainly by acting on targets related to synaptic structure, synaptic function, neuronal survival and neuronal growth. A total of 18 phytochemicals from CR based on UHPLC-MS/MS that corresponded to 85 anti-IS targets. Coniferyl ferulate, neocnidilide and ferulic acid were identified as the key phytochemicals of CR against IS. Its brain protective effects involve anti-inflammatory, anti-oxidative stress, and anti-cell death activities and improves blood circulation. Additionally, the two most important synergistic effects of CR phytochemicals in treating IS are prevention of infection and regulation of blood pressure. In brain samples of Sham mice, L-tryptophan and vanillin were detected, while L-tryptophan, gallic acid, vanillin and cryptochlorogenic acid were detected in IS mice by UHPLC–MS/MS. Our findings provide a pathophysiology relevant pharmacological basis for further researches on IS therapeutic drugs.

Cholinergic degeneration is one of the key pathological hallmarks of Alzheimer’s disease (AD), a condition that is characterized by synaptic disorders and memory impairments. Nerve growth factor (NGF) is secreted in brain regions that receive projections from the basal forebrain cholinergic neurons. The trophic effects of NGF rely on the appropriate maturation of NGF from its precursor, proNGF. The ratio of proNGF/NGF is known to be increased in patients with AD; however, the mechanisms that underlie this observation have yet to be elucidated. Here, we demonstrated that levels of miR-144-3p are increased in the hippocampi and the medial prefrontal cortex of an APP/PS1 mouse model of AD. These mice also exhibited cholinergic degeneration (including the loss of cholinergic fibers, the repression of choline acetyltransferase (ChAT) activity, the reduction of cholinergic neurons, and an increased number of dystrophic neurites) and synaptic/memory deficits. The elevated expression of miR-144-3p specifically targets the mRNA of tissue plasminogen activator (tPA) and reduces the expression of tPA, thus resulting in the abnormal maturation of NGF. The administration of miR-144-3p fully replicated the cholinergic degeneration and synaptic/memory deficits observed in the APP/PS1 mice. The injection of an antagomir of miR-144-3p into the hippocampi partially rescued cholinergic degeneration and synaptic/memory impairments by restoring the levels of tPA protein and by correcting the ratio of proNGF/NGF. Collectively, our research revealed potential mechanisms for the disturbance of NGF maturation and cholinergic degeneration in AD and identified a potential therapeutic target for AD.

Abstract Alzheimer’s disease (AD) is characterized by chronic progressive cognitive deterioration frequently accompanied by psychopathological symptoms, including changes in personality and social isolation, which severely reduce quality of life. Currently, no viable therapies or present-day drugs developed for the treatment of AD symptoms are able to slow or reverse AD progression or prevent the advance of neurodegeneration. As such, non-drug alternatives are currently being tested, including deep brain stimulation (DBS). DBS is an established therapy for several neurological and psychiatric indications, such as movement disorders. Studies assessing DBS for other disorders have also found improvements in cognitive function, providing the impetus for clinical trials on DBS for AD. Targets of DBS in AD clinical trials and animal model studies include the fornix, entorhinal cortex (EC), nucleus basalis of Meynert (NBM), and vertical limb of diagonal band (VDB). However, there is still no comprehensive theory explaining the effects of DBS on AD symptoms or a consensus on which targets provide optimal benefits. This article reviews the anatomy of memory circuits related to AD, as well as studies on DBS rescue of AD in these circuits and the possible therapeutic mechanisms.

We demonstrate the growth of ultra-thin (~5 nm) indium ytterbium oxide (In-Yb-O) thin film using a simple vacuum-free aqueous solution approach for the first time. The influences of Yb addition on the microstructural, chemical, optical, and electrical properties of In2O3 are well investigated. The analyses indicate that Yb dopant could suppress oxygen vacancy defects effectively owing to the lower standard electrode potential, lower electronegativity, and stronger metal-oxide bond strength than that of In. The optimized In-Yb-O thin-film transistors (TFTs) exhibit excellent electrical performance (mobility of 8 cm2/Vs and on/off ratio of ~108) and enhanced stability. The triumph of In-Yb-O TFTs is owing to the high quality In2O3 matrix, the remarkable suppressor of Yb, and the nanometer-thin and atomically smooth nature (RMS: ~0.26 nm) of channel layer. Therefore, the eco-friendly water-induced ultra-thin In-Yb-O channel provides an excellent opportunity for future large-scale and cost-effective electronic applications.

Thin-film transistors (TFTs) made of solution-processable transparent metal oxide semiconductors show great potential for use in emerging large-scale optoelectronics. However, current solution-processed metal oxide TFTs still suffer from relatively poor device performance, hindering their further advancement. In this work, we create a novel ultrathin crystalline indium–boron–oxide (In-B-O) channel layer for high-performance TFTs. We show that high-quality ultrathin (~10 nm) crystalline In-B-O with an atomically smooth nature (RMS: ~0.15 nm) could be grown from an aqueous solution via facile one-step spin-coating. The impacts of B doping on the physical, chemical and electrical properties of the In2O3 film are systematically investigated. The results show that B has large metal–oxide bond dissociation energy and high Lewis acid strength, which can suppress oxygen vacancy-/hydroxyl-related defects and alleviate dopant-induced carrier scattering, resulting in electrical performance improvement. The optimized In-B-O (10% B) TFTs based on SiO2/Si substrate demonstrate a mobility of ~8 cm2/(V s), an on/off current ratio of ~106 and a subthreshold swing of 0.86 V/dec. Furthermore, by introducing the water-processed high-K ZrO2 dielectric, the fully aqueous solution-grown In-B-O/ZrO2 TFTs exhibit excellent device performance, with a mobility of ~11 cm2/(V s), an on/off current of ~105, a subthreshold swing of 0.19 V/dec, a low operating voltage of 5 V and superior bias stress stability. Our research opens up new avenues for low-cost, large-area green oxide electronic devices with superior performance.

Long non-coding RNA (lncRNA) is a kind of non-coding RNA (ncRNA), with a length of 200 nt to 100 kb, that lacks a significant open reading frame (ORF) encoding a protein. lncRNAs are widely implicated in various physiological and pathological processes, such as epigenetic regulation, cell cycle regulation, cell differentiation regulation, cancer, and neurodegenerative diseases, through their interactions with chromatin, protein, and other RNAs. Numerous studies have suggested that lncRNAs are closely linked with the occurrence and development of a variety of diseases, especially neurodegenerative diseases, of which the etiologies are complicated and the underlying mechanisms remain elusive. Determining the roles of lncRNA in the pathogenesis of neurodegenerative diseases will not only deepen understanding of the physiological and pathological processes that occur in those diseases but also provide new ideas and solutions for their diagnosis and prevention. This review aims to highlight the progress of lncRNA research in the pathological and behavioral changes of neurodegenerative diseases. Specifically, we focus on how lncRNA dysfunctions are involved in the pathogenesis of Alzheimer’s disease, Parkinson’s disease, Huntington’s disease, and amyotrophic lateral sclerosis.

Black phosphorus (BP), a single elemental two-dimensional (2D) material with a sizable band gap, meets several critical material requirements in the development of future nanoelectronic applications. This work reports the ambipolar characteristics of few-layer BP, induced using 2D transparent hexagonal boron nitride (h-BN) capping. The 2D h-BN capping have several advantages over conventional Al2O3 capping in flexible and transparent 2D device applications. The h-BN capping technique was used to achieve an electron mobility in the BP devices of 73 cm2V−1s−1, thereby demonstrating n-type behavior. The ambipolar BP devices exhibited ultrafast photodetector behavior with a very high photoresponsivity of 1980 mA/W over the ultraviolet (UV), visible, and infrared (IR) spectral ranges. The h-BN capping process offers a feasible approach to fabricating n-type behavior BP semiconductors and high photoresponse BP photodetectors.

The PSD-95/SAPAP/Shank complex functions as the major scaffold in orchestrating the formation and plasticity of the post-synaptic densities (PSDs). We previously demonstrated that the exquisitely specific SAPAP/Shank interaction is critical for Shank synaptic targeting and Shank-mediated synaptogenesis. Here, we show that the PSD-95/SAPAP interaction, SAPAP synaptic targeting, and SAPAP-mediated synaptogenesis require phosphorylation of the N-terminal repeat sequences of SAPAPs. The atomic structure of the PSD-95 guanylate kinase (GK) in complex with a phosphor-SAPAP repeat peptide, together with biochemical studies, reveals the molecular mechanism underlying the phosphorylation-dependent PSD-95/SAPAP interaction, and it also provides an explanation of a PSD-95 mutation found in patients with intellectual disabilities. Guided by the structural data, we developed potent non-phosphorylated GK inhibitory peptides capable of blocking the PSD-95/SAPAP interaction and interfering with PSD-95/SAPAP-mediated synaptic maturation and strength. These peptides are genetically encodable for investigating the functions of the PSD-95/SAPAP interaction in vivo.

Cholinergic neurons in the diagonal band of Broca degenerate early in Alzheimer’s disease. Here the authors show that in healthy mice, these cholinergic inputs innervate newborn neurons in the hippocampus, and that loss of this innervation in an Alzheimer’s disease model leads to impairments in spatial memory.

The mechanism by which caffeine, an antagonist of adenosine receptors, regulates metabolism is not clear. Here the authors show that adenosine A1R receptor expression is increased in the hypothalamus of diet-induced obesity mice, and that body weight can be alleviated by central administration of caffeine via its action on hypothalamic oxytocin neurons.

Abstract Background Herpes simplex virus type 1 strain 129 (H129) has represented a promising anterograde neuronal circuit tracing tool, which complements the existing retrograde tracers. However, the current H129 derived tracers are multisynaptic, neither bright enough to label the details of neurons nor capable of determining direct projection targets as monosynaptic tracer. Methods Based on the bacterial artificial chromosome of H129, we have generated a serial of recombinant viruses for neuronal circuit tracing. Among them, H129-G4 was obtained by inserting binary tandemly connected GFP cassettes into the H129 genome, and H129-ΔTK-tdT was obtained by deleting the thymidine kinase (TK) gene and adding tdTomato coding gene to the H129 genome. Then the obtained viral tracers were tested in vitro and in vivo for the tracing capacity. Results H129-G4 is capable of transmitting through multiple synapses, labeling the neurons by green florescent protein, and visualizing the morphological details of the labeled neurons. H129-ΔTK-tdT neither replicates nor spreads in neurons alone, but transmits to and labels the postsynaptic neurons with tdTomato in the presence of complementary expressed TK from a helper virus. H129-ΔTK-tdT is also capable to map the direct projectome of the specific neuron type in the given brain regions in Cre transgenic mice. In the tested brain regions where circuits are well known, the H129-ΔTK-tdT tracing patterns are consistent with the previous results. Conclusions With the assistance of the helper virus complimentarily expressing TK, H129-ΔTK-tdT replicates in the initially infected neuron, transmits anterogradely through one synapse, and labeled the postsynaptic neurons with tdTomato. The H129-ΔTK-tdT anterograde monosynaptic tracing system offers a useful tool for mapping the direct output in neuronal circuitry. H129-G4 is an anterograde multisynaptic tracer with a labeling signal strong enough to display the details of neuron morphology.

We investigated the thermal properties of few-layer Mo0.5W0.5S2 using a series of samples with different kinds of capping layers. Temperature-dependent Raman measurements were conducted in the range of 300–500 K, with power-dependent measurements also carried out. It indicated, for the few-layer Mo0.5W0.5S2, the temperature coefficients of the WS2-like E12g mode, MoS2-like E12g mode and A1g mode were −0.0155 cm−1/K, −0.0146 cm−1/K, and −0.0130 cm−1/K, respectively. And the thermal conductivity was estimated to be 44.8 W/mK. Moreover, the Mo0.5W0.5S2 samples coated with capping layers (ZrO2, HfO2) both showed a better thermal stability and a larger thermal conductivity than the one without. The results revealed that the capping layer should be an important factor in the thermal property. Keywords: Mo0.5W0.5S2, TMDs, Thermal properties, High temperature, Capping layers, Raman

Ischemic stroke, which accounts for 87% of all strokes, constitutes the leading cause of morbidity and mortality in China. Although the genetics and epigenetics of stroke have been extensively investigated, few studies have examined their relationships at different stages of stroke. This study assessed the characteristics of transcriptome changes at different stages of ischemic stroke using a mouse model of transient middle cerebral artery occlusion (tMCAO) and bioinformatics analyses. Cerebral cortex tissues from tMCAO mice at days 1, 3, 7, 14, and 28 were removed for RNA-Seq and small RNA-Seq library construction, sequencing, and bioinformatics analysis. We identified differentially expressed (DE) genes and miRNAs and revealed an association of the up-regulated or down-regulated DEmiRNAs with the correspondingly altered DEgene targets at each time point. In addition, different biological pathways were activated at different time points; thus, three groups of miRNAs were verified that may represent potential clinical biomarkers corresponding to days 1, 3, and 7 after ischemic stroke. Notably, this represents the first functional association of some of these miRNAs with stroke, e.g., miR-2137, miR-874-5p, and miR-5099. Together, our findings lay the foundation for the transition from a single-point, single-drug stroke treatment approach to multiple-time-point multi-drug combination therapies.

Summary: Kibra is a synaptic scaffold protein regulating learning and memory. Alterations of Kibra-encoding gene WWC1 cause various neuronal disorders, including Alzheimer’s disease and Tourette syndrome. However, the molecular mechanism underlying Kibra’s function in neurons is poorly understood. Here we discover that Kibra, via its N-terminal WW12 tandem domains, binds to a postsynaptic density enriched protein, Dendrin, with a nanomolar dissociation constant. On the basis of the structure of Kibra WW12 in complex with Dendrin PY motifs, we developed a potent peptide inhibitor capable of specifically blocking the binding between Kibra and Dendrin in neurons. Systematic administration of the inhibitory peptide attenuated excitatory synaptic transmission, completely blocked long-term potentiation induction, and impaired spatial learning and memory. A Kibra mutation found in Tourette syndrome patients causes defects in binding to Dendrin. Thus, Kibra can modulate spatial learning and memory via binding to Dendrin. : Ji et al. report that the memory-related molecule Kibra, via its WW tandem domains, specifically binds to the synaptic protein Dendrin with a low-nanomolar dissociation constant to modulate spatial learning and memory. Keywords: Kibra, Dendrin, WW domains, tandem repeats, scaffold protein, synaptic complex, synaptic transmission, learning and memory, psychiatric disorder, Tourette syndrome

Summary: Retroactive interference (RI) occurs when new incoming information impairs an existing memory, which is one of the primary sources of forgetting. Although long-term potentiation (LTP) reversal shows promise as the underlying neural correlate, the key molecules that control the sensitivity of memory circuits to RI are unknown, and the developmental trajectory of RI effects is unclear. Here we found that depotentiation in the hippocampal dentate gyrus (DG) depends on GluN2A-containing NMDA receptors (NMDARs). The susceptibility of LTP to disruption progressively increases with the rise in the GluN2A/GluN2B ratio during development. The vulnerability of hippocampus-dependent memory to interference from post-learning novelty exploration is subject to similar developmental regulation by NMDARs. Both GluN2A overexpression and GluN2B downregulation in the DG promote RI-induced forgetting. Altogether, our results suggest that a switch in GluN2 subunit predominance may confer age-related differences to depotentiation and underlie the developmental decline in memory resistance to RI. : Ge et al. report that the NMDA receptor GluN2A/GluN2B subunit ratio determines the sensitivity of strengthened neuronal connections to depotentiation. As the ratio rises during development, memories become more vulnerable to disruption by post-learning interference. These findings help to illuminate the mechanism by which forgetting rates may vary with age. Keywords: forgetting, retroactive interference, depotentiation, NMDA receptor

Thin-film transistors (TFTs) made of metal oxide semiconductors are now increasingly used in flat-panel displays. Metal oxides are mainly fabricated via vacuum-based technologies, but solution approaches are of great interest due to the advantages of low-cost and high-throughput manufacturing. Unfortunately, solution-processed oxide TFTs suffer from relatively poor electrical performance, hindering further development. Recent studies suggest that this issue could be solved by introducing a novel heterojunction strategy. This article reviews the recent advances in solution-processed heterojunction oxide TFTs, with a specific focus on the latest developments over the past five years. Two of the most prominent advantages of heterostructure oxide TFTs are discussed, namely electrical-property modulation and mobility enhancement by forming 2D electron gas. It is expected that this review will manifest the strong potential of solution-based heterojunction oxide TFTs towards high performance and large-scale electronics.

A high-performance solar-blind photodetector with a metal−semiconductor−metal structure was fabricated based on amorphous In-doped Ga2O3 thin films prepared at room temperature by radio frequency magnetron sputtering. The photodetector shows a high responsivity (18.06 A/W) at 235 nm with a fast rise time (4.9 μs) and a rapid decay time (230 μs). The detection range was broadened compared with an individual Ga2O3 photodetector because of In doping. In addition, the uneven In distribution at different areas in the film results in different resistances, which causes a quasi-Zener tunneling internal gain mechanism. The quasi-Zener tunneling internal gain mechanism has a positive impact on the fast response speed and high responsivity.

Ginsenoside compound K (GCK), the main metabolite of protopanaxadiol constituents of Panax ginseng, easily produces alkali metal adduct ions during mass spectrometry particularly with lithium. Accordingly, we have developed a rapid and sensitive liquid chromatography–tandem mass spectrometric method for analysis of GCK in human plasma based on formation of a lithium adduct. The analyte and paclitaxel (internal standard) were extracted from 50 µL human plasma using methyl tert-butyl ether. Chromatographic separation was performed on a Phenomenex Gemini C18 column (50 mm×2.0 mm; 5 μm) using stepwise gradient elution with acetonitrile–water and 0.2 mmol/L lithium carbonate at a flow rate of 0.5 mL/min. Detection was performed in the positive ion mode using multiple reaction monitoring of the transitions at m/z 629→449 for the GCK-lithium adduct and m/z 860→292 for the adduct of paclitaxel. The assay was linear in the concentration range 1.00–1000 ng/mL (r2>0.9988) with intra- and inter-day precision of ±8.4% and accuracy in the range of −4.8% to 6.5%. Recovery, stability and matrix effects were all satisfactory. The method was successfully applied to a pharmacokinetic study involving administration of a single GCK 50 mg tablet to healthy Chinese volunteers.

This paper reported AlGaN/GaN high electron mobility transistors (HEMTs) with low sub-threshold swing SS on free-standing GaN wafer. High quality AlGaN/GaN epi-layer has been grown by metal-organic chemical vapor deposition (MOCVD) on free-standing GaN, small full-width hall maximum (FWHM) of 42.9 arcsec for (0002) GaN XRD peaks and ultralow dislocation density (∼104-105 cm-2) were obtained. Due to these extremely high quality material properties, the fabricated AlGaN/GaN HEMTs achieve a low SS (∼60 mV/decade), low hysteresis of 54 mV, and high peak electron mobility μeff of ∼1456 cm2V-1s-1. Systematic study of materials properties and device characteristics exhibits that GaN-on-GaN AlGaN/GaN HEMTs are promising candidate for next generation high power device applications.

The present study aimed to identify microRNAs (miRNAs) that are involved in neuropathic pain and predict their corresponding roles in the pathogenesis and development process of neuropathic pain. The rat model of neuropathic pain caused by spared nerve injury (SNI) was established in Sprague-Dawley male rats, followed by small RNA sequencing of the L3–L6 dorsal root ganglion. Real-time PCR was performed to validate the differently expressed miRNAs. Functional verification was performed by intrathecally injecting the animals with miRNA agomir. A total of 72 differentially expressed miRNAs were identified in the SNI rats, including 33 upregulated and 39 downregulated miRNAs. The results of qPCR further verified the expression levels of rno-miR-6215 (P=0.015), rno-miR-1224 (P=0.030), rno-miR-1249 (P=0.038), and rno-miR-488-3p (P=0.048), which were all significantly downregulated in the SNI rats compared to the control ones. The majority of differentially expressed miRNAs were associated with phosphorylation, intracellular signal transduction, and cell death. Target prediction, Gene Ontology, and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses suggested that these differentially expressed miRNAs targeted genes that are related to axon guidance, focal adhesion, and Ras and Wnt signaling pathways. Moreover, miR-1224 agomir significantly alleviated SNI-induced neuropathic pain. The current findings provide new insights into the role of miRNAs in the pathogenesis of neuropathic pain.

Large size monolayer Molybdenum disulphide (MoS2) was successfully grown by chemical vapor deposition method under an atmospheric pressure. The electrical transport properties of the fabricated back-gate monolayer MoS2 field effect transistors (FETs) were investigated under low temperatures; a peak field effect mobility of 59 cm2V–1s–1 was achieved. With the assist of Raman measurement under low temperature, this work identified the mobility limiting factor for the monolayer MoS2 FETs: homopolar phonon scattering under low temperature and electron-polar optical phonon scattering at room temperature. [ABSTRACT FROM AUTHOR]

Stroke activates microglia pro-inflammatory response that not only induces the early neuronal injuries but also causes the secondary brain infarction. Yet, the underlying mechanisms for how microglia become activated in stroke are still unknown. Here, using the next-generation of RNA sequencing we find a total of 778 genes increasingly expressed in brain of stroke mice. Of these, we identified Hmgb2 as a microglia proinflammatory mediator by promoting the transcription of Ctss. Inhibition of either Hmgb2 or Ctss blocks microglia pro-inflammatory response and protects against brain damages and improves the neurological functions of stroke mice. This study uncovers Hmgb2 and Ctss as the major microglia inflammatory response mediators in stroke and hence warrants the promising targets for stroke therapies. [ABSTRACT FROM AUTHOR]

The aberrant activation of CDK5 has been implicated in neuronal death in stroke. The goal of this study is to determine whether knocking down CDK5 by a peptide-directed lysosomal degradation approach is therapeutically effective against stroke. We synthesized a membrane-permeable peptide that specifically binds to CDK5 with a chaperone-mediated autophagy targeting motif (Tat-CDK5-CTM) and tested its therapeutic effects on a mouse model of ischemic stroke. Our results showed that Tat-CDK5-CTM blocked the CDK5-NR2B interaction, resulting in the degradation of CDK5, which in turn prevented calcium overload and neuronal death in cultured neurons. Tat-CDK5-CTM also reduced the infarction area and neuronal loss and improved the neurological functions in MCAO (Middle cerebral artery occlusion) mice. The peptide-directed lysosomal degradation of CDK5 is a promising therapeutic intervention for stroke. [ABSTRACT FROM AUTHOR]

ZnO microrods (whiskers) were fabricated by a simple thermal oxidation method. The morphologies of the samples were detected by the scanning electron microscope, which showed the ZnO microrods were about 30 μm long with a diameter of 1–2 μm. In the photoluminescence (PL) spectra, only the exciton related emission bands in the ultraviolet region could be obtained at room temperature. And, a new emission band due to the exciton–exciton collision process was observed at the low energy side of the free exciton emission under the excitation intensity of 2.1 kW/cm[sup 2]. This emission band increased nonlinearly. When the excitation intensity was increased above 16 kW/cm[sup 2] some fine structures could also be seen clearly in the PL spectra. These fine structures originated from the cavity modes of the Fabry–Pérot étalon. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The effect of A-site size and disorder on metamagnetic transformation in polycrystalline [Pr.sub.0.5-x][La.sub.x][Ca.sub.0.5]Mn[O.sub.3] and [Pr.sub.0.5][Ca.sub.0.5-x][Ba.sub.x]Mn[O.sub.3] at low temperature is examined. The critical field corresponding to the metamagnetic step has increased and the field-induced magnetization has decreased, while the evolution of resistivity at low temperature with A-site ionic radii variance has displayed strong correlation with that of magnetic properties.

The optical and electrical properties of N-doped ZnO thin films, grown by plasma-assisted molecular beam epitaxy, with different doping concentrations are examined. The results have shown that highly doped samples are heavily compensated and the donor-acceptor pair (DAP) emission band has displayed a strong redshift and broadening with increasing nitrogen doping concentration.

ZnO nanostructures, including nanotowers, nanovolcanoes, nanorods, nanotubes, and nanoflowers is grown by using the hydrothermal technique. Most of the ZnO nanostructures reveal the perfect hexagonal cross section and well-faceted top and side surfaces.

A simple chemical route for ZnS-coated ZnO nanowires with preferential (002) orientation is described, where sodium sulfide and zinc nitrate are used to supply S and Zn atoms at 60 degree Celsius to form ZnS-coated ZnO nanowires structures. In the photoluminescence (PL) spectra an enhanced ultraviolet emission is observed for the ZnS-modified sample, and the visible emission is quenched after S and ZnS coating on ZnO.

Exchange protein directly activated by cAMP (Epac) is a direct effector for the ubiquitous second messenger cAMP. Epac activates the phospholipase Cε (PLCε) pathway. PLCβ has been linked to the synthesis of the endocannabinoid 2-arachidonoylglycerol (2-AG). Here, we report that Epac facilitates endocannabinoid-mediated retrograde synaptic depression through activation of PLCε. Intracellular loading of a selective Epac agonist 8-CPT-2Me-cAMP into ventral tegmental area (VTA) dopamine neurons enabled previously ineffective stimuli to induce depolarization-induced suppression of inhibition (DSI) and long-term depression of IPSCs (I-LTD) in the VTA. DSI and I-LTD are mediated by 2-AG since they were blocked by a diacylglycerol lipase inhibitor. The effects of 8-CPT-2Me-cAMP on DSI and I-LTD were absent in Epac2 and PLCε knock-out mice, but remained intact in Epac1 knock-out mice. These results identify a novel mechanism for on-demand synthesis of retrograde signaling 2-AG by the Epac2-PLCε pathway. We investigated the functional significance of Epac2-PLCε-2-AG signaling in regulating inhibitory synaptic plasticity in VTA dopamine neurons induced by in vivo cocaine exposure. We showed that cocaine place conditioning led to a decrease in the frequency and amplitude of spontaneous IPSCs and an increase in action potential firing in wild-type mice, but not in Epac2 or PLCε knock-out mice. Together, these results indicate that the Epac2-PLCε-2-AG signaling cascade contributes to cocaine-induced disinhibition of VTA dopamine neurons. [ABSTRACT FROM AUTHOR]