Blood–brain barrier (BBB) characteristics are induced and maintained by crosstalk between brain microvascular endothelial cells and neighboring cells. Using in vitro cell models, we previously found ...that a bystander effect was a cause for Japanese encephalitis‐associated endothelial barrier disruption. Brain astrocytes, which neighbor BBB endothelial cells, play roles in the maintenance of BBB integrity. By extending the scope of relevant studies, a potential mechanism has been shown that the activation of neighboring astrocytes could be a cause of disruption of endothelial barrier integrity during the course of Japanese encephalitis viral (JEV) infection. JEV‐infected astrocytes were found to release biologically active molecules that activated ubiquitin proteasome, degraded zonula occludens‐1 (ZO‐1) and claudin‐5, and disrupted endothelial barrier integrity in cultured brain microvascular endothelial cells. JEV infection caused astrocytes to release vascular endothelial growth factor (VEGF), interleukin‐6 (IL‐6), and matrix metalloproteinases (MMP‐2/MMP‐9). Our data demonstrated that VEGF and IL‐6 released by JEV‐infected astrocytes were critical for the proteasomal degradation of ZO‐1 and the accompanying disruption of endothelial barrier integrity through the activation of Janus kinase‐2 (Jak2)/signal transducer and activator of transcription‐3 (STAT3) signaling as well as the induction of ubiquitin–protein ligase E3 component, n‐recognin‐1 (Ubr 1) in endothelial cells. MMP‐induced endothelial barrier disruption was accompanied by MMP‐mediated proteolytic degradation of claudin‐5 and ubiquitin proteasome‐mediated degradation of ZO‐1 via extracellular VEGF release. Collectively, these data suggest that JEV infection could activate astrocytes and cause release of VEGF, IL‐6, and MMP‐2/MMP‐9, thereby contributing, in a concerted action, to the induction of Japanese encephalitis‐associated BBB breakdown. GLIA 2015;63:1915–1932
Main Points
JEV‐infected astrocytes disrupted endothelial barrier integrity.
JEV infection caused astrocytes to release MMP‐2/MMP‐9, IL‐6, and VEGF.
IL‐6 and VEGF activated Jak2/STAT3/Ubr 1 leading to ZO‐1 degradation and endothelial barrier disruption.
A one‐step core/shell electrospinning technique is exploited to fabricate uniform luminous perovskite‐based nanofibers, wherein the perovskite and the polymer are respectively employed in the core ...and the outer shell. Such a coaxial electrospinning technique enables the in situ formation of perovskite nanocrystals, exempting the needs of presynthesis of perovskite quantum dots or post‐treatments. It is demonstrated that not only the luminous electrospun nanofibers can possess color‐tunability by simply tuning the perovskite composition, but also the grain size of the formed perovskite nanocrystals is largely affected by the perovskite precursor stoichiometry and the polymer solution concentration. Consequently, the optimized perovskite electrospun nanofiber yields a high photoluminescence quantum yield of 30.9%, significantly surpassing the value of its thin‐film counterpart. Moreover, owing to the hydrophobic characteristic of shell polymer, the prepared perovskite nanofiber is endowed with a high resistance to air and water. Its photoluminescence intensity remains constant while stored under ambient environment with a relative humidity of 85% over a month and retains intensity higher than 50% of its initial intensity while immersed in water for 48 h. More intriguingly, a white light‐emitting perovskite‐based nanofiber is successfully fabricated by pairing the orange light‐emitting compositional perovskite with a blue light‐emitting conjugated polymer.
Uniform luminous perovskite nanofibers prepared by a one‐step core/shell electrospinning technique are demonstrated herein. The optimized perovskite electrospun nanofiber yields a high photoluminescence quantum yield with improved stability. Finally, a white light‐emitting perovskite‐based nanofiber is also successfully fabricated by pairing the orange light‐emitting compositional perovskite with a blue light‐emitting conjugated polymer.
The continued threat of emerging, highly lethal infectious pathogens such as Middle East respiratory syndrome coronavirus (MERS‐CoV) calls for the development of novel vaccine technology that offers ...safe and effective prophylactic measures. Here, a novel nanoparticle vaccine is developed to deliver subunit viral antigens and STING agonists in a virus‐like fashion. STING agonists are first encapsulated into capsid‐like hollow polymeric nanoparticles, which show multiple favorable attributes, including a pH‐responsive release profile, prominent local immune activation, and reduced systemic reactogenicity. Upon subsequent antigen conjugation, the nanoparticles carry morphological semblance to native virions and facilitate codelivery of antigens and STING agonists to draining lymph nodes and immune cells for immune potentiation. Nanoparticle vaccine effectiveness is supported by the elicitation of potent neutralization antibody and antigen‐specific T cell responses in mice immunized with a MERS‐CoV nanoparticle vaccine candidate. Using a MERS‐CoV‐permissive transgenic mouse model, it is shown that mice immunized with this nanoparticle‐based MERS‐CoV vaccine are protected against a lethal challenge of MERS‐CoV without triggering undesirable eosinophilic immunopathology. Together, the biocompatible hollow nanoparticle described herein provides an excellent strategy for delivering both subunit vaccine candidates and novel adjuvants, enabling accelerated development of effective and safe vaccines against emerging viral pathogens.
To improve vaccination efforts against Middle East respiratory syndrome coronavirus (MERS‐CoV), a virus‐mimicking vaccine is herein prepared with a capsid‐like hollow polymeric nanoparticle loaded with STING agonists and coated in MERS‐CoV antigens. The viromimetic nanoparticle facilitates safe and effective vaccination against the lethal virus and offers a versatile platform for combatting emerging infectious threats.
The exotic photophysical properties of organic–inorganic hybrid perovskite with long exciton lifetimes and small binding energy have appeared as promising front‐runners for next‐generation ...non‐volatile flash photomemory. However, the long photo‐programming time of photomemory limits its application on light‐fidelity (Li‐Fi), which requires high storage capacity and short programming times. Herein, the spatially addressable perovskite in polystyrene‐block‐poly(ethylene oxide) (PS‐b‐PEO)/perovskite composite film as an photoactive floating gate is demonstrated to elucidate the effect of morphology on the photo‐responsive characteristics of photomemory. The chelation between lead ion and PEO segment promotes the anti‐solvent functionalities of the perovskite/PS‐b‐PEO composite film, thus allowing the solution‐processable poly(3‐hexylthiophene‐2,5‐diyl) (P3HT) to act as the active channel. Through manipulating the interfacial area between perovskite and P3HT, fast photo‐induced charge transfer rate of 0.056 ns−1, high charge transfer efficiency of 89%, ON/OFF current ratio of 104, and extremely low programming time of 5 ms can be achieved. This solution‐processable and fast photo‐programmable non‐volatile flash photomemory can trigger the practical application on Li‐Fi.
The spatially addressable perovskite in a polystyrene‐block‐poly(ethylene oxide) (PS‐b‐PEO)/perovskite composite film as an photoactive floating gate is demonstrated. By manipulating the interfacial area between the perovskite and active channel, a fast photo‐induced charge transfer rate of 0.056 ns−1, high charge transfer efficiency of 89%, ON/OFF current ratio of 104, and extremely low programming time of 5 ms can be achieved.
Aims
To explore the effects of preferred music therapy on peer attachment, depression, and salivary cortisol among early adolescents.
Background
As adolescents enter puberty, they start to seek ...partnering relationships among peers. Peer attachment is central for adolescents and greatly influences their physical and psychological development.
Design
A pre‐test‐posttest control group design.
Methods
The data were collected from July ‐ October 2016. A total of 65 individuals were included. The treatment group received 40 min of music therapy twice per week over the course of 10 weeks. The control group maintained its typical routine. The research data were collected using structured questionnaires, including basic information, the Inventory of Peer Attachment, the Beck Depression Inventory‐II questionnaires, and salivary cortisol concentrations. Statistical analysis methods included percentages, chi‐square tests, t tests, analyses of covariance, and the Johnson–Neyman technique.
Results
There were statistically significant differences in peer attachment, depression, and salivary cortisol levels in the music group compared to the control group (p < 0.05). Additionally, the findings showed that early adolescents with more severe depression experienced greater improvement through preferred music therapy.
Conclusion
The results allude to the beneficial effects of receiving preferred music therapy in terms of the peer attachment, depression, and salivary cortisol levels of early adolescents. Adjustments should be made based on the characteristics of student groups to develop suitable and safe music therapy and to reduce the risks of poor mental health.
目的
探讨首选音乐疗法对早期青少年同伴依恋、抑郁和唾液皮质醇的影响。
背景
随着青少年进入青春期,他们开始寻求同伴之间的伙伴关系。同伴依恋是青少年的中心,对他们的身心发展影响很大。
设计
试验前‐试验后控制组设计。
方法
数据收集自2016年7月至10月。共有65人参加。治疗组在10周内每周接受两次40分钟的音乐治疗。对照组保持其典型的常规。研究数据采用结构化问卷收集,包括基本信息、同伴依恋量表、Beck抑郁量表II问卷和唾液皮质醇浓度。统计分析方法包括百分比、卡方检验、t检验、协方差分析和Johnson‐Neyman技术。
结果
音乐组的同伴依恋、抑郁和唾液皮质醇水平与对照组相比有统计学意义(P<0.05)。此外,研究结果表明,抑郁更严重的早期青少年通过首选的音乐治疗经历了更大的改善。
结论
研究结果表明,在早期青少年的同伴依恋、抑郁和唾液皮质醇水平方面,接受首选音乐治疗的会产生有益效果。应根据学生群体的特点进行调整,以发展合适、安全的音乐治疗,降低心理健康不良的风险。
A molecular nano‐floating gate (NFG) of pentacene‐based transistor memory devices is developed using conjugated polymer nanoparticles (CPN) as the discrete trapping sites embedded in an insulating ...polymer, poly (methacrylic acid) (PMAA). The nanoparticles of polyfluorene (PF) and poly(fluorene‐alt‐benzo2,1,3thiadiazole (PFBT) with average diameters of around 50–70 nm are used as charge‐trapping sites, while hydrophilic PMAA serves as a matrix and a tunneling layer. By inserting PF nanoparticles as the floating gate, the transistor memory device reveals a controllable threshold voltage shift, indicating effectively electron‐trapping by the PF CPN. The electron‐storage capability can be further improved using the PFBT‐based NFG since their lower unoccupied molecular orbital level is beneficial for stabilization of the trapped charges, leading a large memory window (35 V), retention time longer than 104 s with a high ON/OFF ratio of >104. In addition, the memory device performance using conjugated polymer nanoparticle NFG is much higher than that of the corresponding polymer blend thin films of PF/polystyrene. It suggests that the discrete polymer nanoparticles can be effectively covered by the tunneling layer, PMAA, to achieve the superior memory characteristics.
A molecular nano‐floating gate approach using conjugated polymer nanoparticles is developed for achieving high performance transistor memory devices. The transistor memory device using discrete polyfluorene and poly(fluorene‐alt‐benzo2,1,3thiadiazole nanoparticles as the floating gates can effectively trap the electrons and lead to a large memory window, long retention time, and a high ON/OFF ratio of >104.
Solution‐processable organic–inorganic hybrid perovskite materials with a wealth of exotic semiconducting properties have appeared as the promising front‐runners for next‐generation electronic ...devices. Further, regarding its well photoresponsibility, various perovskite‐based photosensing devices are prosperously developed in recent years. However, most exploited devices to date only transiently transduce the optical signals into electrical circuits while under illumination, which necessitates using additional converters to further store the output signals for recording the occurrence of light stimulation. Herein, a nonvolatile perovskite‐based floating‐gate photomemory with a multilevel memory behavior is demonstrated, for which a floating gate comprising a polymer matrix impregnated with perovskite nanoparticles is employed. Owing to the well photoresponsibility introduced by the embedded nanoparticles, the device is enabled to access multiple wavelength response and the functionalities of recording power/time‐dependent illumination under no vertical electrical field. Intriguingly, a nonvolatility of photorecording exceeding three months with a high On/Off current ratio over 104 can be achieved.
A nonvolatile perovskite‐based photomemory with a multilevel memory behavior is developed for the first time. By using a floating gate composed of a perovskite/polymer blend, the device is enabled to access multiple wavelength response and the functionalities of recording power‐dependent/time‐related illumination under no vertical electrical field. Intriguingly, a nonvolatility of photorecording exceeding three months with a high On/Off current ratio of 104 can be realized.
Organic-inorganic hybrid perovskite has become one of the most important photoactive materials owing to its intense light-harvesting property as well as its facile solution processability. Besides ...its photovoltaic applications, a novel photo-programmed transistor memory was recently developed based on the device architecture of a floating-gate transistor memory using a polymer/perovskite blend as the gate dielectric with the non-volatile memory characteristics of decent light response, applicable On/Off current ratio, and long retention time. In this study, we further clarify the influence of polymer matrix selection on the photo-response and memory properties of derived hybrid perovskite-based photo-memory devices. Four different host polymers, polystyrene (PS), poly(4-vinylphenol) (PVPh), poly(methyl methacrylate) (PMMA), and poly(methacrylic acid) (PMAA), were systematically investigated for comparison herein. This revealed that dissimilar chemical interactions existed between the host polymers and perovskite, resulting in the distinct memory behavior of the derived photo-memory devices, attributable to the different morphologies of the hybrid dielectric layers and the different sizes of the distributed perovskite nanoparticles (NPs). The photo-response behavior and the resultant On/Off current ratio increased as the size of the embedded perovskite NPs decreased, due to the enhanced photo-induced charge transfer across the dielectric/pentacene interface, benefiting from the better confinement effect of perovskite NPs in the polymer matrix. These results demonstrate the influence of perovskite NP aggregation at the dielectric/pentacene interface on the resultant memory behavior of the newly developed photo-memory device.
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