Last‐minute labeling: Mesoporous silica nanoparticles (MSNs) were modified with a very short half‐life fluorine‐18‐labeled azide radiotracer by a cycloaddition reaction after the MSNs had reached the ...tumor site in mice. The tumor could then be visualized successfully with positron emission tomography.
The present study was performed to examine the induction of apoptotic cell death and autophagy by blue LED irradiation, and the contribution of autophagy to apoptosis in B cell lymphoma A20 and RAMOS ...cells exposed to blue LED. Irradiation with blue LED reduced cell viability and induced apoptotic cell death, as indicated by exposure of phosphatidylserine on the plasma outside membrane and fragmentation of DNA. Furthermore, the mitochondrial membrane potential increased, and apoptotic proteins (PARP, caspase 3, Bax, and bcl-2) were observed. In addition, the level of intracellular superoxide anion (O2−) gradually increased. Interestingly the formation of autophagosomes and level of LC3-II were increased in blue LED-irradiated A20 and RAMOS cells, but inhibited after pretreatment with 3-methyladenine (3-MA), widely used as an autophagy inhibitor. Inhibition of the autophagic process by pretreatment with 3-MA blocked blue LED irradiation-induced caspase-3 activation. Moreover, a significant reduction of both the early and late phases of apoptosis after transfection with ATG5 and beclin 1 siRNAs was shown by the annexin V/PI staining, indicating a crucial role of autophagy in blue LED-induced apoptosis in cells. Additionally, the survival rate of mice irradiated with blue LED after injection with A20 cells increased compared to the control group. Our data demonstrate that blue LED irradiation induces apoptosis via the mitochondrial-mediated pathway, in conjunction with autophagy. Further studies are needed to elucidate the precise mechanism of blue LED-induced immune cell death.
Variations in the El Niño/Southern Oscillation (ENSO) are associated with a wide array of regional climate extremes and ecosystem impacts
. Robust, long-lead forecasts would therefore be valuable for ...managing policy responses. But despite decades of effort, forecasting ENSO events at lead times of more than one year remains problematic
. Here we show that a statistical forecast model employing a deep-learning approach produces skilful ENSO forecasts for lead times of up to one and a half years. To circumvent the limited amount of observation data, we use transfer learning to train a convolutional neural network (CNN) first on historical simulations
and subsequently on reanalysis from 1871 to 1973. During the validation period from 1984 to 2017, the all-season correlation skill of the Nino3.4 index of the CNN model is much higher than those of current state-of-the-art dynamical forecast systems. The CNN model is also better at predicting the detailed zonal distribution of sea surface temperatures, overcoming a weakness of dynamical forecast models. A heat map analysis indicates that the CNN model predicts ENSO events using physically reasonable precursors. The CNN model is thus a powerful tool for both the prediction of ENSO events and for the analysis of their associated complex mechanisms.
In cancer patients, metastasis of tumors to sentinel lymph nodes (LNs) predicts disease progression and often guides treatment decisions. The mechanisms underlying tumor LN metastasis are poorly ...understood. By using comparative transcriptomics and metabolomics analyses of primary and LN-metastatic tumors in mice, we found that LN metastasis requires that tumor cells undergo a metabolic shift toward fatty acid oxidation (FAO). Transcriptional coactivator yes-associated protein (YAP) is selectively activated in LN-metastatic tumors, leading to the up-regulation of genes in the FAO signaling pathway. Pharmacological inhibition of FAO or genetic ablation of YAP suppressed LN metastasis in mice. Several bioactive bile acids accumulated to high levels in the metastatic LNs, and these bile acids activated YAP in tumor cells, likely through the nuclear vitamin D receptor. Inhibition of FAO or YAP may merit exploration as a potential therapeutic strategy for mitigating tumor metastasis to LNs.
The aim of this study was to examine the inhibitory effect of blue light (BL) on the proliferation of metastatic cancer cells and synergistic properties with chemo‐drugs. BL significantly inhibited ...the proliferation of B cell lymphoma (A20 and RAMOS) cells in a dose‐dependent manner. Anti‐proliferative effect of BL irradiation was identified to be associated with the inhibition of proliferating‐cell nuclear antigen expression and cell cycle by decreasing S‐phase cells. Consistent with its inhibitory effects, BL irradiation at 20 J/cm2 daily for 10 days inhibited metastasis of cancer cells which were distributed and invaded to other organs including bone marrow, liver, kidney, etc., and induced paraplegia, thereby leading to an increased survival rate of tumor‐bearing mice. Anti‐proliferative activity of BL was expanded in solid tumor cells including pancreatic carcinoma (Mia PaCa‐2, PANC‐1), lung carcinoma A549 and colorectal carcinoma HCT116 cells. Additionally, combination with chemo‐drugs such as 5‐FU and gemcitabine resulted in an increase in the anti‐proliferative activity after BL irradiation accompanied by regulating mRNA translational process via inhibition of p70S6K, 4EBP‐1 and eIF4E phosphorylation during cellular proliferation. These results indicate the anti‐metastatic and photo‐biogoverning abilities of BL irradiation as a potent therapeutic potential for repressing the progression of tumor cells.
Anti‐proliferative effect of BL irradiation was associated with the inhibition of protein synthesis. Combination with chemo‐drugs such as 5‐FU and gemcitabine resulted in an increase in the anti‐proliferative activity after BL irradiation accompanied by regulating mRNA translational process via inhibition of p70S6K, 4EBP‐1, and eIF4E phosphorylation during cellular proliferation. These results indicate the anti‐metastatic and photo‐biogoverning abilities of BL irradiation as a potent therapeutic potential for repressing the progression of tumor cells.
Multi‐resonance thermally activated delayed fluorescence (MR‐TADF) molecules based on boron and nitrogen atoms are emerging as next‐generation blue emitters for organic light‐emitting diodes (OLEDs) ...due to their narrow emission spectra and triplet harvesting properties. However, intermolecular aggregation stemming from the planar structure of typical MR‐TADF molecules that leads to concentration quenching and broadened spectra limits the utilization of the full potential of MR‐TADF emitters. Herein, a deep‐blue MR‐TADF emitter, pBP‐DABNA‐Me, is developed to suppress intermolecular interactions effectively. Furthermore, photophysical investigation and theoretical calculations reveal that adding biphenyl moieties to the core body creates dense local triplet states in the vicinity of S1 and T1 energetically, letting the emitter harvest excitons efficiently. OLEDs based on pBP‐DABNA‐Me show a high external quantum efficiency (EQE) of 23.4% and a pure‐blue emission with a Commission Internationale de L'Eclairage (CIE) coordinate of (0.132, 0.092), which are maintained even at a high doping concentration of 100 wt%. Furthermore, by incorporating a conventional TADF sensitizer, deep‐blue OLEDs with a CIE value of (0.133, 0.109) and an extremely high EQE of 30.1% are realized. These findings provide insight into design strategies for developing efficient deep‐blue MR‐TADF emitters with fast triplet upconversion and suppressed self‐aggregation.
A multi‐resonance thermally activated delayed fluorescence (MR‐TADF) emitter exhibiting deep‐blue emission with Commission Internationale de L'Eclairage coordinates of (0.132, 0.092), narrow full width at half maximum of 22 nm, and high external quantum efficiency of 23.4% is developed by introducing bulky biphenyls and N‐biphenyl‐N‐ortho‐dimethylphenylamine that create dense local triplet states and suppress intramolecular aggregation.
The aim of this study was to determine the effects and molecular mechanism of blue light emitting diode (LED) in tumor cells. A migration and invasion assay for the metastatic behavior of mouse colon ...cancer CT‐26 and human fibrosarcoma HT‐1080 cells was performed. Cancer cell migration‐related proteins were identified by obtaining a 2‐dimensional gel electrophoresis (2‐DE) in total cellular protein profile of blue LED‐irradiated cancer cells, followed by matrix‐assisted laser desorption/ionization‐time of flight (MALDI‐TOF) analysis of proteins. Protein levels were examined by immunoblotting. Irradiation with blue LED inhibited CT‐26 and HT‐1080 cell migration and invasion. The anti‐metastatic effects of blue LED irradiation were associated with inhibition of matrix metalloproteinase (MMP)‐2 and MMP‐9 expression. P38 MAPK phosphorylation was increased in blue LED‐irradiated CT‐26 and HT‐1080 cells, but was inhibited after pretreatment with SB203580, a specific inhibitor of p38 MAPK. Inhibition of p38 MAPK phosphorylation by SB203580 treatment increased number of migratory cancer cells in CT‐26 and HT‐1080 cells, indicating that blue LED irradiation inhibited cancer cell migration via phosphorylation of p38 MAPK. Additionally blue LED irradiation of mice injected with CT‐26 cells expressing luciferase decreased early stage lung metastasis compared to untreated control mice. These results indicate that blue LED irradiation inhibits cancer cell migration and invasion in vitro and in vivo.
Irradiation with blue LED inhibited CT‐26 and HT‐1080 cell migration and invasion. The anti‐metastatic effects of blue LED irradiation were associated with inhibition of matrix metalloproteinase (MMP)‐2 and MMP‐9 expression. Inhibition of p38 MAPK increased number of migratory cancer cells, indicating that blue LED irradiation inhibited cancer cell migration via phosphorylation of p38 MAPK.
The term "nanosheets" has been coined recently to describe supported and free-standing "ultrathin film" materials, with thicknesses ranging from a single atomic layer to a few tens of nanometers. ...Owing to their physicochemical properties and their large surface area with abundant accessible active sites, nanosheets (NSHs) of inorganic materials such as Au, amorphous carbon, graphene, and boron nitride (BN) are considered ideal building blocks or scaffolds for a wide range of applications encompassing electronic and optical devices, membranes, drug delivery systems, and multimodal contrast agents, among others. A wide variety of synthetic methods are employed for the manufacturing of these NSHs, and they can be categorized into (1) top-down approaches involving exfoliation of layered materials, or (2) bottom-up approaches where crystal growth of nanocomposites takes place in a liquid or gas phase. Of note, polymer template liquid exfoliation (PTLE) methods are the most suitable as they lead to the fabrication of high-performance and stable hybrid NSHs and NSH composites with the appropriate quality, solubility, and properties. Moreover, PTLE methods allow for the production of stimulus-responsive NSHs, whose response is commonly driven by a favorable growth in the appropriate polymer chains onto one side of the NSHs, resulting in the ability of the NSHs to roll up to form nanoscrolls (NSCs), i.e., open tubular structures with tunable interlayer gaps between their walls. On the other hand, this review gives insight into the potential of the stimulus-responsive nanostructures for biosensing and controlled drug release systems, illustrating the last advances in the PTLE methods of synthesis of these nanostructures and their applications.
Almost 100% internal quantum efficiency (IQE) is achieved with a green fluorescent organic light‐emitting diode (OLED) exhibiting 30% external quantum efficiency (EQE). The OLED comprises an ...exciplex‐forming co‐host system doped with a fluorescent dye that has a strong delayed fluorescence as a result of reverse intersystem crossing (RISC); the exciplex‐forming co‐hosts stimulate energy transfer and charge balance in the system. The orientation of the transition dipole moment of the fluorescent dye is shown to have an influence on the EQE of the device.
Organic–inorganic hybrid perovskite light‐emitting diodes (PeLEDs) are promising for next‐generation optoelectronic devices due to their potential to achieve high color purity, efficiency, and ...brightness. Although the external quantum efficiency (EQE) of PeLEDs has recently surpassed 20%, various strategies are being pursued to increase EQE further and reduce the EQE gap compared to other LED technologies. A key point to further boost EQE of PeLEDs is linked to the high refractive index of the perovskite emissive layer, leading to optical losses of more than 70% of emitted photons. Here, it is demonstrated that a randomly distributed nanohole array with high‐index contrast can effectively enhance outcoupling efficiency in PeLEDs. Based on a comprehensive optical analysis on the perovskite thin film and outcoupling structure, it is confirmed that the nanohole array effectively distributes light into the substrate for improved outcoupling, allowing for 1.64 times higher light extraction. As a result, highly efficient red/near‐infrared PeLEDs with a peak EQE of 14.6% are demonstrated.
A highly efficient red/near‐infrared perovskite light‐emitting diode (PeLED) with a peak external quantum efficiency of 14.6% is demonstrated using a randomly distributed nanohole array (NHA) with high‐index contrast. The NHA properly compensates the disadvantage of high refractive index of the perovskite emissive layer without altering the PeLED structure, allowing for a 1.64‐times enhanced outcoupling.
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