Organic light-emitting diodes (OLEDs) are a promising light-source technology for future generations of display1,2. Despite great progress3–12, it is still challenging to produce blue OLEDs with ...sufficient colour purity, lifetime and efficiency for applications. Here, we report pure-blue (Commission Internationale de l’ Eclairage (CIE) coordinates of 0.13, 0.16) OLEDs with high efficiency (external quantum efficiency of 32 per cent at 1,000 cd m−2), narrow emission (full-width at half-maximum of 19 nm) and good stability (95% of the initial luminacnce (LT95) of 18 hours at an initial luminance of 1,000 cd m−2). The design is based on a two-unit stacked tandem hyperfluorescence OLED with improved singlet-excited-state energy transfer from a sky-blue assistant dopant exhibiting thermally activated delayed fluorescence (TADF) called hetero-donor-type TADF(HDT-1) to a pure-blue emitter. With stricter control of device fabrication and procedures it is expected that device lifetimes will further improve to rival commercial fluorescent blue OLEDs.Pure-blue organic LEDs with narrow emission and improved stability show promise for display applications.
Chronic kidney disease (CKD)‐associated mental disorders have been attributed to the excessive accumulation of hemodialysis‐resistant indoxyl‐3‐sulfate (I3S) in the brain. I3S not only induces ...oxidative stress but is also a potent endogenous agonist of the aryl hydrocarbon receptor (AhR). Here, we investigated the role of AhR in CKD‐induced brain disorders using a 5/6 nephrectomy‐induced CKD mouse model, which showed increased I3S concentration in both blood and brain, anxiety and impaired novelty recognition, and AhR activation in the anterior cortex. GFAP+ reactive astrocytes were increased accompanied with the reduction of glutamate transporter 1 (GLT1) on perineuronal astrocytic processes (PAPs) in the anterior cingulate cortex (ACC) in CKD mice, and these alterations were attenuated in both neural lineage‐specific and astrocyte‐specific Ahr conditional knockout mice (nAhrCKO and aAhrCKO). By using chronic I3S treatment in primary astrocytes and glia‐neuron (GN) mix cultures to mimic the CKD brain microenvironment, we also found significant reduction of GLT1 expression and activity in an AhR‐dependent manner. Chronic I3S treatment induced AhR‐dependent pro‐oxidant Nox1 and AhR‐independent anti‐oxidant HO‐1 expressions. Notably, AhR mediates chronic I3S‐induced neuronal activity enhancement and synaptotoxicity in GN mix, not neuron‐enriched cortical culture. In CKD mice, neuronal activity enhancement was observed in ACC and hippocampal CA1, and these responses were abrogated by both nAhrCKO and aAhrCKO. Finally, intranasal AhR antagonist CH‐223191 administration significantly ameliorated the GLT1/PAPs reduction, increase in c‐Fos+ neurons, and memory impairment in the CKD mice. Thus, astrocytic AhR plays a crucial role in the CKD‐induced disturbance of neuron‐astrocyte interaction and mental disorders.
Main Points
CKD elevates brain I3S to activate astrocytic AhR, which mediates astrogliosis with GLT1 hypofunction and enhances neuronal activity in ACC and hippocampus.
Intranasal AhR antagonist administration ameliorates CKD‐induced brain/behavioral changes.
Three thermally activated delayed fluorescence (TADF) molecules, namely PQ1, PQ2, and PQ3, are composed of electron‐accepting (A) tetrabenzoa,cphenazine (TBPZ) and electron‐donating (D) phenoxazine ...(PXZ) units are designed and characterized. The combined effects of planar acceptor manipulation and high steric hindrance between D and A units endow high molecular rigidity that suppresses nonradiative decay of the excitons with improved photoluminescence quantum yields (PLQYs). Particularly, the well‐aligned excited states involving a singlet and a triplet charge‐transfer excited states and a localized excited triplet state in PQ3 enhances the reverse intersystem crossing rate constant (kRISC) with a short delay lifetime (τd). The orange–red OLED based on PQ3 displays a maximum external EL quantum efficiency (EQE) of 27.4 % with a well‐suppressed EL efficiency roll‐off owing to a completely horizontal orientation of the transition dipole moment in the film state.
The expansion of TBPZ acceptor plane well‐controlled the excited states involving 1CT, 3CT and 3LE states, which enhances the kRISC by remarkably shortening τd and induced a completely horizontal orientation of the TDM. Consequently, PQ3 displayed an orange red EL max at 586 nm, PLQY of ca. 83 %, kRISC of 8×105 s−1, τd of 2.7 μs, S values of −0.49, and deliver high EQE of 27.4 %.
The conformational distribution and mutual interconversion of thermally activated delayed fluorescence (TADF) emitters significantly affect the exciton utilization. However, their influence on the ...photophysics in amorphous film states is still not known due to the lack of a suitable quantitative analysis method. Herein, we used temperature‐dependent time‐resolved photoluminescence spectroscopy to quantitatively measure the relative populations of the conformations of a TADF emitter for the first time. We further propose a new concept of “self‐doping” for realizing high‐efficiency nondoped OLEDs. Interestingly, this “compositionally” pure film actually behaves as a film with a dopant (quasi‐equatorial form) in a matrix (quasi‐axial form). The concentration‐induced quenching that may occur at high concentrations is thus expected to be effectively relieved. The “self‐doping” OLED prepared with the newly developed TADF emitter TP2P‐PXZ as a neat emitting layer realizes a high maximum external quantum efficiency of 25.4 % and neglectable efficiency roll‐off.
Until now, the influence of the conformational distribution on the photophysics and device performance of thermally activated delayed fluorescence (TADF) emitters has not been clear. Herein, conformational populations in disordered solid states are quantitatively measured for the first time. A high‐performance “self‐doping” OLED with a maximum external quantum efficiency of 25.4 % is achieved.
Both the detrimental effect of prenatal exposure to di-(2-ethylhexyl)-phthalate (DEHP) and the beneficial effects of physical exercise on brain functions have been reported. The oxytocin pathway has ...been implicated in the onset of maternal behaviors. Epigenetic modification of the oxytocin receptor gene (OXTR) through DNA methylation has been associated with the pathogenesis of neuropsychiatric disorders. The purpose of this study was to investigate the effects of prenatal DEHP exposure on oxytocin-regulated maternal behaviors and to examine the protective effect of exercise. Pregnant rats (F0) were fed with vehicle or DEHP during gestation and the offspring females (F1) were assessed for their maternal behaviors by pup retrieval test at postpartum. The results showed that reduced pup retrieval activities without significant alteration of stress responses were observed in the prenatally DEHP-exposed females. Prenatal DEHP exposure decreased the expressions of oxytocin,
mRNA, and oxytocin receptor, and increased
methylation in the hypothalamus of postpartum female rats. There were no significant effects of exercise on behavioral, biochemical, and epigenetic measurements. These results suggest that prenatal DEHP exposure has a long-term adverse effect on maternal behaviors;
hyper-methylation may be a potential epigenetic mechanism for this alteration, which cannot be prevented by physical exercise during childhood.
Diabetic ketoacidosis (DKA) is associated with dehydration and which can cause acute kidney injury (AKI). The proportion of AKI in children and adolescents with DKA has not been reported in East ...Asian population. This study aimed to identify the prevalence of AKI and to determine whether there is an association between AKI severity and recovery time from metabolic acidosis in children and adolescents with DKA. Medical records of children and adolescents (aged 1.5 times the calculated expected baseline creatinine level. Patients were divided into three groups based on AKI severity: no AKI, mild AKI, and severe AKI. In total, 170 (56.5%) patients with DKA presented AKI (mild AKI, 116 38.5%; severe AKI, 54 18.0%). Heart rate and laboratory parameters related to dehydration, such as corrected sodium level and blood urea nitrogen, were strongly associated with AKI development (P0.01). Blood pH, plasma glucose, and potassium levels were also associated with AKI. A negative correlation with borderline significance between the estimated glomerular filtration rate (eGFR) and recovery time from metabolic acidosis was observed in the severe AKI group. AKI was highly prevalent in children and adolescents with DKA. An association between AKI and biomarkers indicating dehydration was noted. The recovery time from metabolic acidosis following treatment may be longer in children with a decreased eGFR who present with severe AKI. AKI is a common complication in children with DKA.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Ankylosing spondylitis (AS) is an autoimmune disease affecting mainly spine and sacroiliac joints and adjacent soft tissues. Genome-wide association studies (GWASs) are used to evaluate genetic ...associations and to predict genetic risk factors that determine the biological basis of disease susceptibility. We aimed to explore the race-specific SNP susceptibility of AS in Taiwanese individuals and to investigate the association between HLA-B27 and AS susceptibility SNPs in Taiwan.
Genotyping data were collected from a medical center participating in the Taiwan Precision Medicine Initiative (TPMI) in the northern district of Taiwan. We designed a case-control study to identify AS susceptibility SNPs through GWAS. We searched the genome browser to find the corresponding susceptibility genes and used the GTEx database to confirm the regulation of gene expression. A polygenic risk score approach was also applied to evaluate the genetic variants in the prediction of developing AS.
The results showed that the SNPs located on the sixth chromosome were related to higher susceptibility in the AS group. There was no overlap between our results and the susceptibility SNPs found in other races. The 12 tag SNPs located in the MHC region that were found through the linkage disequilibrium method had higher gene expression. Furthermore, Taiwanese people with HLA-B27 positivity had a higher proportion of minor alleles. This might be the reason that the AS prevalence is higher in Taiwan than in other countries. We developed AS polygenic risk score models with six different methods in which those with the top 10% polygenic risk had a fivefold increased risk of developing AS compared to the remaining group with low risk.
A total of 147 SNPs in the Taiwanese population were found to be statistically significantly associated with AS on the sixth pair of chromosomes and did not overlap with previously published sites in the GWAS Catalog. Whether those genes mapped by AS-associated SNPs are involved in AS and what the pathogenic mechanism of the mapped genes is remain to be further studied.
Multiple-resonance thermally activated delayed fluorescence (MR-TADF) emitters have emerged as an important component of organic light-emitting diodes (OLEDs) because of their narrowband emission and ...high exciton utilization efficiency. However, the chemical space of MR-TADF emitters remains mostly unexplored because of the lack of suitable synthetic protocols. Herein, we demonstrate a sequential multiple borylation reaction that provides new synthetically accessible chemical space. ω-DABNA, the proof-of-concept material, exhibited narrowband green TADF with a full width at half-maximum of 22 nm and a small singlet–triplet energy gap of 13 meV. The OLED employing it as an emitter exhibited electroluminescence at 512 nm, with Commission International de l’Éclairage coordinates of (0.13, 0.73) and a high external quantum efficiency (EQE) of 31.1%. Moreover, the device showed minimum efficiency roll-off, with an EQE of 29.4% at 1000 cd m–2.
Lead (Pb) is nonbiodegradable and toxic to the lungs. To investigate the potential mechanisms of Pb‐induced reactive oxygen species (ROS) accumulation and cell death in the lungs, human non‐small ...lung carcinoma H460 cells were stimulated with Pb(NO3)2 in this study. The results showed that Pb(NO3)2 stimulation increased cell death by inducing cell apoptosis which showed a reduced Bcl‐2 expression and an enhanced caspase 3 activation. Pb(NO3)2 also caused the production of H2O2 in H460 cells that triggering the buildup of ROS and mitochondrial membrane potential loss. We found that Pb(NO3)2 modulates oxidoreductive activity through reduced the glutathione‐disulfide reductase and glutathione levels in Pb(NO3)2‐exposed H460 cells. Furthermore, the superoxide dismutase (SOD) upstream molecule sirtuin 3 (SIRT3) was increased with Pb(NO3)2 dose. Collectively, these results demonstrate that Pb(NO3)2 promotes lung cell death through SIRT3/SOD‐mediated ROS accumulation and mitochondrial dysfunction.
Three amphiphilic block copolymers are employed to form polymeric micelles and function as nanocarriers to disperse hydrophobic aggregation‐induced emission (AIE) dyes, 1,1,2,3,4,5‐hexaphenylsilole ...(HPS) and/or bis(4‐(N‐(1‐naphthyl) phenylamino)‐phenyl)fumaronitrile (NPAFN), into aqueous solution for biological studies. Compared to their virtually non‐emissive properties in organic solutions, the fluorescence intensity of these AIE dyes has increased significantly due to the spatial confinement that restricts intramolecular rotation of these dyes and their better compatibility in the hydrophobic core of polymeric micelles. The effect of the chemical structure of micelle cores on the photophysical properties of AIE dyes are investigated, and the fluorescence resonance energy transfer (FRET) from the green‐emitting donor (HPS) to the red‐emitting acceptor (NPAFN) is explored by co‐encapsulating this FRET pair in the same micelle core. The highest fluorescence quantum yield (∼62%) could be achieved by encapsulating HPS aggregates in the micelles. Efficient energy transfer (>99%) and high amplification of emission (as high as 8 times) from the NPAFN acceptor could also be achieved by spatially confining the HPS/NPAFN FRET pair in the hydrophobic core of polymeric micelles. These micelles could be successfully internalized into the RAW 264.7 cells to demonstrate high‐quality fluorescent images and cell viability due to improved quantum yield and reduced cytotoxicity.
Highly efficient fluorescence probes are achieved through the encapsulation of aggregation‐induced emission molecules, 1,1,2,3,4,5‐hexaphenylsilole (HPS) and/or bis(4‐(N‐(1‐naphthyl) phenylamino)‐phenyl)fumaronitrile (NPAFN) in the core of polymeric micelles. Bright fluorescence cell images are shown with tunable colors of green directly from HPS aggregates and red through efficient fluorescence resonance energy transfer (FRET) from HPS aggregates to NPAFN aggregates.
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