Genetic and clinical characteristics of ZNF408-related familial exudative vitreoretinopathy.

OBJECTIVE: To analyze the clinical and genetic characteristics of zinc finger protein 408 (ZNF408)-related familial exudative vitreoretinopathy (FEVR) in a Chinese cohort. METHODS: Ninety families from Chongqing and 16 families from Xinjiang were selected according to fundus lesion characteristics. Peripheral venous blood was collected from patients and their families; genomic DNA was extracted for whole exome sequencing. Relationships between genotype and phenotype in patients with ZNF408-related FEVR were analyzed. RESULTS: ZNF408 variants were detected in three patients (2.83%, 3/106). ZNF408 variants in these three probands were all missense mutations at novel sites. One proband had a ZNF408 and LRP5 double-gene variant, and two probands had ZNF408 single-gene variants. Patients with double-gene variants did not display more severe clinical manifestations. CONCLUSIONS: This study expands the spectrum of known ZNF408 variants and confirms that ZNF408 variants can cause FEVR. Most variants detected in this study have not been reported in the literature and are suspected pathogenic variants of FEVR. In patients with FEVR, phenotype and genotype do not necessarily display a direct one-to-one relationship.

A Highly Efficient Electromagnetic Wave Absorption System with Graphene Embedded in Hybrid Perovskite.

To cope with the explosive increase in electromagnetic radiation intensity caused by the widespread use of electronic information equipment, high-performance electromagnetic wave (EMW)-absorbing materials that can adapt to various frequency bands of EMW are also facing great demand. In this paper, CH3NH3PbI3/graphene (MG) high-performance EMW-absorbing materials were innovatively synthesized by taking organic-inorganic hybrid perovskite (OIHP) with high equilibrium holes, electron mobility, and accessible synthesis as the main body, graphene as the intergranular component, and adjusting the component ratio. When the component ratio was 16:1, the thickness of the absorber was 1.87 mm, and MG's effective EMW absorption width reached 6.04 GHz (11.96-18.00 GHz), achieving complete coverage of the Ku frequency band. As the main body of the composite, CH3NH3PbI3 played the role of the polarization density center, and the defects and vacancies in the crystal significantly increased the polarization loss intensity; graphene, as a typical two-dimensional material distributed in the crystal gap, built an efficient electron transfer channel, which significantly improved the electrical conductivity loss strength. This work effectively broadened the EMW absorption frequency band of OIHP and promoted the research process of new EMW-absorbing materials based on OIPH.

NiMnO3 Anchored on Reduced Graphene Oxide Nanosheets: A New High-Performance Microwave Absorbing Material.

With the increasing influence of electromagnetic radiation on precision instruments and organisms, there is an urgent need for research on lightweight and high-strength electromagnetic wave absorbing materials. This study has probed into a new composite absorbing material based on reduced graphene oxide (rGO)-NiMnO3, where the like-core-shell NiMnO3 is anchored on the rGO nanosheets to significantly improve the electromagnetic wave dissipation ability of the composite material using the inter-component dipole polarization and interface polarization. At the same time, NiMnO3 can effectively adjust the impedance matching ratio of rGO so that electromagnetic waves can effectively enter the absorbing material. At a thickness of 3.73 mm, the maximum absorption strength of rGO-NiMnO3 reaches -61.4 dB at 6.6 GHz; at a thickness of 2.5 mm, the adequate absorption bandwidth is 10.04-18.00 GHz, achieving a full coverage for the Ku band. As a new option for preparing lightweight and broadband electromagnetic wave absorbing materials, rGO-NiMnO3 is an ideal material for electromagnetic wave protection.

A flexible electrostatic nanogenerator and self-powered capacitive sensor based on electrospun polystyrene mats and graphene oxide films.

Electrostatic nanogenerators or capacitive sensors that leverage electrostatic induction for power generation or sensing, has attracted significant interests due to their simple structure, ease of fabrication, and high device stability. However, in order for such devices to work, an additional power source or a post-charging process is necessary to activate the electrostatic effect. In this work, an electrostatic nanogenerator is fabricated using electrospun polystyrene (PS) mats and dip-coated graphene oxide (GO) films as the self-charged components. The electret performances of the PS mats and GO films are characterized via the electrostatic force microscopy phase shift and surface potential measurements. With a multilayer device structure that consists of top electrodes/GO films/spacer/electrospun PS mats/bottom electrodes, the resultant device acts as an electrostatic generator that operates in the noncontact mode. The nanogenerator can output a peak voltage of ca. 6.41 V and a peak current of ca. 6.57 nA at a rate of 1 Hz of mechanical compression, and with no attenuation of electrical outputs even after 50 000 cycles over a 13 h period. Furthermore, this as-prepared device is also capable of serving as a self-powered capacitive sensor for detection of tiny mechanical impacts and measurement of human finger bending. This results of this work provides a new avenue to easily fabricate electrostatic nanogenerators with high durability and self-powered capacitive sensors for the detection of small impacts.

Effects of ion migration and improvement strategies for the operational stability of perovskite solar cells.

The fundamental factor affecting the stability of perovskite solar cells, ion migration, has been reviewed, which is found to be closely related to the degradation of perovskite solar cells. Characterization methods like impedance spectroscopy and galvanostatic measurement to identify ion migration in perovskite films have been reviewed. The influence of light on ion migration was further discussed, which could largely explain the photo-stability decay in most perovskite solar cells. Finally, several solutions to inhibit ion migration for better operational stability of perovskite solar cells were summarized, including bulk passivation, interface passivation and grain boundary passivation. Several strategies have also been proposed to further improve the stablity of perovskite solar cells.

Evaluation of the neuroprotective effect of EGCG: a potential mechanism of mitochondrial dysfunction and mitochondrial dynamics after subarachnoid hemorrhage.

(-)-Epigallocatechin-3-gallate (EGCG), the main bioactive component of tea catechins, exhibits broad-spectrum health efficacy against mitochondrial damage after subarachnoid hemorrhage (SAH). The mechanisms, however, are largely unknown. Here, the ability of EGCG to rescue mitochondrial dysfunction and mitochondrial dynamics following the inhibition of cell death was investigated by using in vitro and in vivo SAH models. EGCG blocked the cytosolic channel ([Ca2+])i influx via voltage-gated calcium channels (VGCCs), which induced mitochondrial dysfunction, including mitochondrial membrane potential depolarization and reactive oxygen species (ROS) release. As expected, EGCG ameliorated oxyhemoglobin (OxyHb)-induced impairment of mitochondrial dynamics by regulating the expression of Drp1, Fis1, OPA1, Mfn1, and Mfn2. As a result, EGCG restored the increases in fragmented mitochondria and the mtDNA copy number in the OxyHb group to almost the normal level after SAH. In addition, the normal autophagic flux induced by EGCG at both the initiation and formation stages regulated Atg5 and Beclin-1 after SAH for the timely elimination of damaged mitochondria. In the end, EGCG increased the neurological score by decreasing cell death through the cyt c-mediated intrinsic apoptotic pathway. The results revealed the mechanisms behind the neuroprotective effects of EGCG via inhibition of the overloaded [Ca2+]i-induced mitochondrial dysfunction and the imbalanced mitochondrial fusion and fission cycle. Therefore, the simultaneous inhibition and timely elimination of damaged mitochondria could determine the therapeutic effect of EGCG.

Proton Migration in Hybrid Lead Iodide Perovskites: From Classical Hopping to Deep Quantum Tunneling.

The organic-inorganic halide perovskites (OIHPs) have shown enormous potential for solar cells, while problems like the current-voltage hysteresis and the long-term instability have seriously hindered their applications. Ion migrations are believed to be relevant. But the atomistic details still remain unclear. Here we study the migrations of ions in CH3NH3PbI3 (MAPbI3) at varying temperatures ( T's), using combined experimental and first-principle theoretical methods. Classical hopping of the iodide ions is the main migration mechanism at moderate T's. Below ∼270 K, the kinetic constant for ionic migration still shows an Arrenhius dependency, but the much lower activation energy is attributed to the migration of H+. A gradual classical-to-quantum transition takes place between ∼140 and ∼80 K. Below ∼80 K, the kinetic constant becomes T-independent, suggesting that deep quantum tunneling of H+ takes over. This study gives direct experimental evidence for the migrations of H+s in MAPbI3 and confirms their quantum nature.

p38 Inhibitor Protects Mitochondrial Dysfunction by Induction of DJ-1 Mitochondrial Translocation After Subarachnoid Hemorrhage.

p38 mitogen-activated protein kinase (MAPK) is a major player in mitochondrial dysfunction after subarachnoid hemorrhage (SAH). Moreover, DJ-1, which responds to oxidative stress and translocates to mitochondria, maintains mitochondrial homeostasis. Although a few studies have demonstrated that DJ-1 indirectly regulates p38 activation, the relationship between DJ-1 and p38 in mitochondrial dysfunction after SAH has not been delineated. Using an in vitro SAH model, alterations in p38, p-p38, DJ-1, and autophagic-related protein expression were detected. As expected, p38 inhibitor significantly blocked excessive expression of p38 and p-p38 after SAH, whereas total DJ-1 expression and mitochondrial DJ-1 were up-regulated. Further analysis showed that p38 inhibitor significantly blocked oxyhemoglobin (OxyHb) induced mitochondrial dysfunction, including mitochondrial membrane potential depolarization and reactive oxygen species (ROS) release. In addition, p38 inhibitor restored OxyHb-induced abnormal autophagic flux at the initiation and formation stage by regulating Atg5, beclin-1, the ratio of LC3-II/LC3-I, and p62 expression. This study suggested that overexpression of p38 induced the accumulation of mitochondrial dysfunction partly due to abnormal activation of autophagy, which largely relied on DJ-1 mitochondrial translocation.

In Situ Cesium Modification at Interface Enhances the Stability of Perovskite Solar Cells.

A consensus has been reached that organic transport layer (e.g., Spiro-OMeTAD) in perovskite solar cell (PSC) is prone to be impact by mobile ions in perovskite film during long-term operation. Here, we incorporate cesium acetate as a buffer layer into perovskite solar cells to mitigate this detrimental behavior, in which cesium acetate is sandwiched between perovskite and organic transport layer. The mobile ions that migrate toward the organic transport layer (e.g., MA+) are gradually consumed by cesium acetate, resulting in cesium-rich perovskite at the interface. This in situ reaction and the subsequent Cs incorporation greatly enhance the operational stability of PSC without efficiency loss. The optimized PSC presents a power conversion efficiency of 20.9% with an open-circuit voltage of 1.18 V, maintaining ∼80% of its initial efficiency after 4500 min continuous operation at maximum power point. This new strategy opens up a new opportunity for fabricating stable perovskite solar cells.

Efficient Perovskite Solar Cells Fabricated Through CsCl-Enhanced PbI2 Precursor via Sequential Deposition.

The fabrication of high-quality perovskite film highly relies on chemical composition and the synthesis method of perovskite. So far, sequentially deposited MA0.03 FA0.97 Pb(I0.97 Br0.03 )3 polycrystalline film is adopted to produce high-performance perovskite solar cells with record power conversion efficiency (PCE). Fewer grain boundaries and incorporation of inorganic cation (e.g., cesium) would further increase device performance via sequential deposition. Here, cesium chloride (CsCl) is introduced into lead iodide (PbI2 ) precursor solution that beneficially modulates the property of PbI2 film, leading to larger grains with cesium incorporation in the resulting perovskite film. The enlarged crystal grains originate from a slower nucleation process for CsCl-containing PbI2 film when reacting with formamidine iodide, confirmed by in situ confocal photoluminescence imaging. Photovoltaic devices based on CsCl-containing PbI2 film demonstrate a higher averaging efficiency of 21.3% than 20.3% of the devices without CsCl additives for reverse scan. More importantly, the device stability is improved by CsCl additives that retain over 90% of their initial PCE value after 4000 min tracking at maximum power point under 1-sun illumination. This work paves a way to further improve the photovoltaic performance of mixed-cation-halide perovskite solar cells via a sequential deposition method.

A Two-Dimensional Hole-Transporting Material for High-Performance Perovskite Solar Cells with 20 % Average Efficiency.

A readily available small molecular hole-transporting material (HTM), OMe-TATPyr, was synthesized and tested in perovskite solar cells (PSCs). OMe-TATPyr is a two-dimensional π-conjugated molecule with a pyrene core and four phenyl-thiophene bridged triarylamine groups. It can be readily synthesized in gram scale with a low lab cost of around US$ 50 g-1 . The incorporation of the phenyl-thiophene units in OMe-TATPyr are beneficial for not only carrier transportation through improved charge delocalization and intermolecular stacking, but also potential trap passivation via Pb-S interaction as supported by depth-profiling XPS, photoluminescence, and electrochemical impedance analysis. As a result, an impressive best power conversion efficiency (PCE) of up to 20.6 % and an average PCE of 20.0 % with good stability has been achieved for mixed-cation PSCs with OMe-TATPyr with an area of 0.09 cm2 . A device with an area of 1.08 cm2 based on OMe-TATPyr demonstrates a PCE of 17.3 %.

MiR-129-5p inhibits glioma cell progression in vitro and in vivo by targeting TGIF2.

This study purposed to explore the correlation between miR-129-5p and TGIF2 and their impacts on glioma cell progression. Differentially expressed miRNA was screened through microarray analysis. MiR-129-5p expression levels in glioma tissues and cells were measured by qRT-PCR. CCK-8 assay, flow cytometer, transwell assay and wound-healing assay were employed to detect cell proliferation, apoptosis and cycle, invasiveness and migration, respectively. Dual-luciferase reporting assay was performed to confirm the targeted relationship between miR-129-5p and TGIF2. The effects of TGIF2 expression on cell biological functions were also investigated using the indicated methods. Tumour xenograft was applied to explore the impact of miR-129-5p on tumorigenesis in vivo. MiR-129-5p expression was down-regulated in both glioma tissues and glioma cells, while TGIF2 expression was aberrantly higher than normal level. Dual-luciferase reporter assay validated the targeting relation between miR-129-5p and TGIF2. Overexpression of miR-129-5p or down-regulation of TGIF2 inhibited the proliferation, invasion and migration capacity of glioma cells U87 and U251, and meanwhile blocked the cell cycle as well as induced cell apoptosis. MiR-129-5p overexpression repressed the tumour development in vivo. MiR-129-5p and TGIF2 had opposite biological functions in glioma cells. MiR-129-5p could inhibit glioma cell progression by targeting TGIF2, shining light for the development of target treatment for glioma.

Associations between TNFSF4, TNFSF8 and TNFSF15 and Behçet's disease but not VKH syndrome in Han Chinese.

The present study was designed to explore the interrelationship between single nucleotide polymorphisms (SNP) of the tumor necrosis factor superfamily (TNFSF) and its respective receptor superfamily (TNFRSF) genes and Behcet's disease (BD) and Vogt-Koyanagi-Harada syndrome (VKH) in Han Chinese. The study sample included 796 patients with BD, 792 patients with VKH syndrome, and 1604 healthy controls. The genotyping of 35 SNPs was performed by MassARRAY platform (Sequenom), iPLEX Gold Assay, PCR-restriction fragment length polymorphism assay and TaqMan SNP assay. The mRNA expression levels of TNFSF4, TNFSF8 and TNFSF15 were analyzed by real-time PCR. The IL-6 and TNF-α expression levels were measured by ELISA. The A allele and AA genotype frequencies of TNFSF4/rs1234313 were significantly increased, and the GG genotype frequency of rs1234313 was decreased in subjects with BD. Significantly lower frequencies of the C allele and the CC genotype and higher frequencies of the TT and CT genotypes of TNFSF15/rs4246905 were observed in BD patients. A decreased frequency of the A allele of TNFSF8/rs7028891 was observed in BD patients. The expression of TNFSF15 in CT carriers was significantly higher than that in CC/TT individuals. Increased IL-6 expression and TNF-α production were found in the TNFSF15 CT carriers compared with the CC/TT genotype carriers. No significant differences were observed between the VKH patients and controls. This study indicates that TNFSF4, TNFSF15 and TNFSF8 may participate in the susceptibility to BD among Han Chinese.

Differential expression of microRNAs contributed to the health efficacy of EGCG in in vitro subarachnoid hemorrhage model.

(-)-Epigallocatechin-3-gallate (EGCG) exhibits a broader spectrum health efficacy in subarachnoid hemorrhage (SAH) therapy; the mechanisms, however, are largely unknown. Given that miRNAs play important roles in regulation of thousands of gene expressions, the effect of EGCG on the expression of miRNAs was investigated to explore the multi-targeting actions of EGCG by using an in vitro SAH model. MTT and western blot assays were used to assess the health effects of EGCG in SAH progression; the results showed that oxyhemoglobin (OxyHb)-induced cell proliferation and excessive autophagic activation were significantly inhibited by 50 µM EGCG, but not by 1 µM EGCG. By high throughput sequencing analysis, the miRNA profiles of normal, SAH and EGCG (1 and 50 µM) groups were compared and a total of 953 miRNAs were identified. Of 192 differentially expressed miRNAs, 43 miRNAs were significantly differentially expressed in SAH (p < 0.01). However, EGCG significantly increased the number of differential expressions of miRNAs, which showed 144 and 138 miRNAs (112 and 115 upregulated, 32 and 23 downregulated, p < 0.01) in 1 µM and 50 µM EGCG groups, respectively. Among all the differentially expressed miRNAs, 13 miRNAs were shared by the three groups. 5 miRNAs (miR-218-5p, miR-218b, miR-143-3p, miR-101a-3p, miR-30a-3p) were detected in both SAH and EGCG 1 µM groups, and 104 miRNAs were shared by the EGCG 1 µM and EGCG 50 µM groups. Only 1 miRNA (miR-532-5p) was discovered in both SAH and EGCG 50 µM groups. Moreover, 24, 22 and 20 specific differentially expressed miRNAs were discovered in SAH, 1 µM and 50 µM EGCG groups, respectively. The predicted target genes of differentially expressed miRNAs showed that the most impacted MAPK signaling pathway, particularly the upregulated p38 expression in the SAH group, was restored to the normal level in both EGCG groups, but the calcium signaling pathway was enriched only in the EGCG 50 µM group. These results revealed that differential expression of miRNAs is fundamental to understand the multiple targets actions of EGCG in SAH therapy, and simultaneously targeting more robust signaling pathways could determine the therapeutic effects of EGCG.

Light-Independent Ionic Transport in Inorganic Perovskite and Ultrastable Cs-Based Perovskite Solar Cells.

Due to light-induced effects in CH3NH3-based perovskites, such as ion migration, defects formation, and halide segregation, the degradation of CH3NH3-based perovskite solar cells under maximum power point is generally implicated. Here we demonstrated that the effect of light-enhanced ion migration in CH3NH3PbI3 can be eliminated by inorganic Cs substitution, leading to an ultrastable perovskite solar cell. Quantitatively, the ion migration barrier for CH3NH3PbI3 is 0.62 eV under dark conditions, larger than that of CsPbI2Br (0.45 eV); however, it reduces to 0.07 eV for CH3NH3PbI3 under illumination, smaller than that for CsPbI2Br (0.43 eV). Meanwhile, photoinduced halide segregation is also suppressed in Cs-based perovskites. Cs-based perovskite solar cells retained >99% of the initial efficiency (10.3%) after 1500 h of maximum power point tracking under AM1.5G illumination, while CH3NH3PbI3 solar cells degraded severely after 50 h of operation. Our work reveals an uncovered mechanism for stability improvement by inorganic cation substitution in perovskite-based optoelectronic devices.

Enhanced long-term stability of perovskite solar cells by 3-hydroxypyridine dipping.

Lead halide perovskite solar cells show poor stability due to their ionic material character. Here, we introduce a dipping method to modify the perovskite layer with 3-hydroxypyridine molecules. The long-term stability of solar cells is greatly enhanced and shows no obvious decay after 90 hour steady-state measurements.

Reduction in Autophagy by (-)-Epigallocatechin-3-Gallate (EGCG): a Potential Mechanism of Prevention of Mitochondrial Dysfunction After Subarachnoid Hemorrhage.

Mitochondrial dysfunction and subsequent autophagy, which are common features in central nervous system (CNS) disorders, were found to contribute to neuronal cell injury after subarachnoid hemorrhage (SAH). (-)-Epigallocatechin-3-gallate (EGCG), the main biological active of tea catechin, is well known for its beneficial effects in the treatment of CNS diseases. Here, the ability of EGCG to rescue cellular injury and mitochondrial function following the improvement of autophagic flux after SAH was investigated. As expected, EGCG-protected mitochondrial function depended on the inhibition of cytosolic Ca2+ concentration ([Ca2+]i) influx via voltage-gated calcium channels (VGCCs) and, consequently, mitochondrial Ca2+ concentration ([Ca2+]m) overload via mitochondrial Ca2+ uniporter (MCU). The attenuated [Ca2+]i and [Ca2+]m levels observed in the EGCG-treated group likely lessened oxyhemoglobin (OxyHb)-induced mitochondrial dysfunction, including mitochondrial membrane potential depolarization, mitochondrial membrane permeability transition pore (mPTP) opening, reactive oxygen species (ROS), and cytochrosome c (cyt c) releasing. Subsequently, EGCG can restore the disrupted autophagy flux after SAH both at the initiation and formation stages by regulating Atg5, LC3B, and Becn-1 (Beclin-1) mRNA expressions. Thus, precondition EGCG resulted in autophagosomes and more autolysosomes compared with SAH group. As a result, EGCG pre-treatment increased the neurological score and decreased cell death. This study suggested that the mitochondrial dysfunction and abnormal autophagy flux synergistically contribute to SAH pathogenesis. Thus, EGCG can be regarded as a new pharmacological agent that targets both mitochondria and altered autophagy in SAH therapy.

Quantification of light-enhanced ionic transport in lead iodide perovskite thin films and its solar cell applications.

Ionic transport in organometal halide perovskites is of vital importance because it dominates anomalous phenomena in perovskite solar cells, from hysteresis to switchable photovoltaic effects. However, excited state ionic transport under illumination has remained elusive, although it is essential for understanding the unusual light-induced effects (light-induced self-poling, photo-induced halide segregation and slow photoconductivity response) in organometal halide perovskites for optoelectronic applications. Here, we quantitatively demonstrate light-enhanced ionic transport in CH3NH3PbI3 over a wide temperature range of 17-295 K, which reveals a reduction in ionic transport activation energy by approximately a factor of five (from 0.82 to 0.15 eV) under illumination. The pure ionic conductance is obtained by separating it from the electronic contribution in cryogenic galvanostatic and voltage-current measurements. On the basis of these findings, we design a novel light-assisted method of catalyzing ionic interdiffusion between CH3NH3I and PbI2 stacking layers in sequential deposition perovskite synthesis. X-ray diffraction patterns indicate a significant reduction of PbI2 residue in the optimized CH3NH3PbI3 thin film produced via light-assisted sequential deposition, and the resulting solar cell efficiency is increased by over 100% (7.5%-15.7%) with little PbI2 residue. This new method enables fine control of the reaction depth in perovskite synthesis and, in turn, supports light-enhanced ionic transport.

Flexible perovskite solar cells based on the metal-insulator-semiconductor structure.

The metal-insulator-semiconductor (MIS) structure is applied to perovskite solar cells, in which the traditional compact layer TiO2 is replaced by Al2O3 as the hole blocking material to realize an all-low-temperature process. Flexible devices based on this structure are also realized with excellent flexibility, which hold 85% of their initial efficiency after bending 100 times.

A polymer scaffold for self-healing perovskite solar cells.

Advancing of the lead halide perovskite solar cells towards photovoltaic market demands large-scale devices of high-power conversion efficiency, high reproducibility and stability via low-cost fabrication technology, and in particular resistance to humid environment for long-time operation. Here we achieve uniform perovskite film based on a novel polymer-scaffold architecture via a mild-temperature process. These solar cells exhibit efficiency of up to ∼ 16% with small variation. The unencapsulated devices retain high output for up to 300 h in highly humid environment (70% relative humidity). Moreover, they show strong humidity resistant and self-healing behaviour, recovering rapidly after removing from water vapour. Not only the film can self-heal in this case, but the corresponding devices can present power conversion efficiency recovery after the water vapour is removed. Our work demonstrates the value of cheap, long chain and hygroscopic polymer scaffold in perovskite solar cells towards commercialization.