Research into organic light emitters employing multiple resonance-induced thermally activated delayed fluorescence (MR-TADF) materials is presently attracting a great deal of attention due to the ...potential for efficient deep-blue emission. However, the origins and mechanisms of successful TADF are unclear, as many MR-TADF materials do not show TADF behaviour in solution, but only as particular pure solids. Here, an investigation into a well-known MR-TADF material, DABNA-1, together with other new MR materials (9H-quinolino3,2,1-klphenothiazin-9-one (QPO) and 9H-quinolino-3,2,1-kl-phenothiazin-9-one 5,5-dioxide (QP3O)), yields new insights regarding the origin of TADF. Although a material system may support the concept of MR, inefficiency in both forward and reverse intersystem crossings forbids TADF unless a suitable host material allows an exciplex-like host–emitter interaction that boosts TADF. This boosted-TADF mechanism can be generalized to any fluorescence dye that lacks TADF in the photoluminescence measurement but has a thermally accessible S1–T1 energy gap, opening the way to high-performance organic light-emitting diodes.This study reveals the importance of host–guest interactions for effective multiple-resonance thermally activated delayed fluorescence in organic light emitters.
A new light‐driven chiral molecular switch doped in a stable blue phase (BP) liquid crystal allows wide optical tunability of three‐dimensional cubic nanostructures with a selective reflection ...wavelength that is reversibly tuned through the visible region. Moreover, unprecedented reversible light‐directed red, green, and blue reflections of the self‐organized three‐dimensional cubic nanostructure in a single film are demonstrated for the first time. Additionally, unusual isothermal photo‐stimulated less ordered BP II to more ordered BP I phase transition was observed in the system.
Natural self-assembled three-dimensional photonic crystals such as blue-phase liquid crystals typically assume cubic lattice structures. Nonetheless, blue-phase liquid crystals with distinct crystal ...symmetries and thus band structures will be advantageous for optical applications. Here we use repetitive electrical pulses to reconfigure blue-phase liquid crystals into stable orthorhombic and tetragonal lattices. This approach, termed repetitively applied field, allows the system to relax between each pulse, gradually transforming the initial cubic lattice into various intermediate metastable states until a stable non-cubic crystal is achieved. We show that this technique is suitable for engineering non-cubic lattices with tailored photonic bandgaps, associated dispersion and band structure across the entire visible spectrum in blue-phase liquid crystals with distinct composition and initial crystal orientation. These field-free blue-phase liquid crystals exhibit large electro-optic responses and can be polymer-stabilized to have a wide operating temperature range and submillisecond response speed, which are promising properties for information display, electro-optics, nonlinear optics, microlasers and biosensing applications.
A series of new amino (NH)-type hydrogen-bonding (H-bonding) compounds comprising 2-(2′-aminophenyl)benzothiazole and its extensive derivatives were designed and synthesized. Unlike in the hydroxyl ...(OH)-type H-bonding systems, one of the amino hydrogens can be replaced with electron-donating/withdrawing groups. This, together with a versatile capability for modifying the parent moiety, makes feasible the comprehensive spectroscopy and dynamics studies of amino-type excited-state intramolecular proton transfer (ESIPT), which was previously inaccessible in the hydroxyl-type ESIPT systems. Empirical correlations were observed among the hydrogen-bonding strength (the N–H bond distances and proton acidity), ESIPT kinetics, and thermodynamics, demonstrating a trend that the stronger N–H···N hydrogen bond leads to a faster ESIPT, as experimentally observed, and a more exergonic reaction thermodynamics. Accordingly, ESIPT reaction can be harnessed for the first time from a highly endergonic type (i.e., prohibition) toward equilibrium with a measurable ESIPT rate and then to the highly exergonic, ultrafast ESIPT reaction within the same series of amino-type intramolecular H-bond system.
Hyperthermia has been reported to be an effective cancer treatment modality, as tumor cells are more temperature-sensitive than their normal counterparts. Since the ambient temperature can be ...increased by placing magnetic nanoparticles in an alternating magnetic field it has become of interest to incorporate these magnetic nanoparticles into biodegradable nanofibers for possible endoscopic hyperthermia treatment of malignant tumors. In this preliminary investigation we have explored various characteristics of biodegradable electrospun chitosan nanofibers containing magnetic nanoparticles prepared by different methods. These methods included: (1) E-CHS-Fe3O4, with electrospun chitosan nanofibers directly immersed in a magnetic nanoparticle solution; (2) E-CHS-Fe2+, with the electrospun chitosan nanofibers initially immersed in Fe+2/Fe+3 solution, followed by chemical co-precipitation of the magnetic nanoparticles. The morphology and crystalline phase of the magnetic electrospun nanofiber matrices were determined by scanning electron microscopy, transmission electron microscopy, selected area electron diffraction, and X-ray diffraction spectroscopy. The magnetic characteristics were measured using a superconducting quantum interference device. The heating properties of these magnetic electrospun nanofiber matrices in an alternating magnetic field were investigated at a frequency of 750kHz and magnetic intensity of 6.4kW. In vitro cell incubation experiments indicated that these magnetic electrospun nanofiber matrices are non-cytotoxic and can effectively reduce tumor cell proliferation upon application of a magnetic field.
•Adequate surgical margin for OSCC needs to be re-evaluated.•The study enrolled 15,654 patients with OSCC from the TCR database.•Advanced N stage and positive margin are major risk factors for poor ...CSS and OS.•Surgical margins <4 mm and <5 mm predict poor CSS and OS, respectively.
Margin status and lymph node metastasis are the most important prognostic factors for oral cancers. However, while adequate surgical resection is crucial for local control and prognosis, the definition of clear margins has long been a subject of debate. In this study, we analyzed data from a nationwide population-based cancer registry database and evaluated the impact of surgical margins on cancer-specific survival (CSS) and overall survival (OS) as well as the optimal cutoff of adequate surgical margins.
This analysis included all cases of oral cancer diagnosed from 2011 to 2017 that were reported to the Taiwan Cancer Registry database. The staging system was converted from American Joint Committee on Cancer (AJCC) version 7 to AJCC version 8. Kaplan–Meier analysis and Cox proportional-hazards regression were performed to identify covariates that were significantly associated with CSS and OS.
Between 2011 and 2017, 15,654 of a total of 36,091 cases diagnosed with oral cancers were included in the final analyses. Advanced N stage, positive margins, and advanced T stage are the leading risk factors for poor CSS and OS. When surgical margins were subdivided into 1-mm intervals from 5 mm to positive margin, we found that surgical margins <4 mm and <5 mm predict poor CSS and OS, respectively.
This is the first nationwide, population-based cohort to revisit the question of the adequate surgical margins for oral cancers. We conclude that surgical margins ≥4 mm and ≥5 mm are adequate for good CSS and OS, respectively.
Although there have been intense efforts to fabricate large three-dimensional photonic crystals in order to realize their full potential, the technologies developed so far are still beset with ...various material processing and cost issues. Conventional top-down fabrications are costly and time-consuming, whereas natural self-assembly and bottom-up fabrications often result in high defect density and limited dimensions. Here we report the fabrication of extraordinarily large monocrystalline photonic crystals by controlling the self-assembly processes which occur in unique phases of liquid crystals that exhibit three-dimensional photonic-crystalline properties called liquid-crystal blue phases. In particular, we have developed a gradient-temperature technique that enables three-dimensional photonic crystals to grow to lateral dimensions of ~1 cm (~30,000 of unit cells) and thickness of ~100 μm (~ 300 unit cells). These giant single crystals exhibit extraordinarily sharp photonic bandgaps with high reflectivity, long-range periodicity in all dimensions and well-defined lattice orientation.Conventional fabrication approaches for large-size three-dimensional photonic crystals are problematic. By properly controlling the self-assembly processes, the authors report the fabrication of monocrystalline blue phase liquid crystals that exhibit three-dimensional photonic-crystalline properties.
The photophysical properties of the phenothiazine-triphenyltriazine derivative, PTZ-TRZ, are reinvestigated. The results, in combination with the computational approaches, lead us to draw the ...conclusion that the complicated excitation behavior in toluene (ref ), in part, is due to the UV absorption cutoff region for toluene where the <315 nm excitation is greatly distorted by solvent absorption, i.e., the inner filter effect, in a regular sample cuvette (1.0 cm path length). Switching the solvent to cyclohexane with the UV cutoff wavelength at 235 nm simplifies the results. In cyclohexane, two isomers exist for PTZ-TRZ in the ground state and quasi-axial and quasi-equatorial conformers. Upon electronic excitation, both quasi-axial and quasi-equatorial conformers undergo structural relaxation to an energy minimum state where the phenothiazine is in a planar configuration.
The T790M mutation is the major resistance mechanism to first- and second-generation TKIs in EGFR-mutant NSCLC. This study aimed to investigate the utility of droplet digital PCR (ddPCR) for ...detection of T790M in plasma circulating tumor DNA (ctDNA), and explore its impact on prognosis.
This prospective study enrolled 80 advanced lung adenocarcinoma patients treated with gefitinib, erlotinib, or afatinib for TKI-sensitizing mutations between 2015 and 2019. Plasma samples were collected before TKI therapy and at tri-monthly intervals thereafter. Genotyping of ctDNA for T790M was performed using a ddPCR EGFR Mutation Assay. Patients were followed up until the date of death or to the end of 2021.
Seventy-five of 80 patients experienced progressive disease. Fifty-three (71%) of 75 patients underwent rebiopsy, and T790M mutation was identified in 53% (28/53) of samples. Meanwhile, plasma ddPCR detected T790M mutation in 23 (43%) of 53 patients. The concordance rate of T790M between ddPCR and rebiopsy was 76%, and ddPCR identified 4 additional T790M-positive patients. Ten (45%) of 22 patients who did not receive rebiopsy tested positive for T790M by ddPCR. Serial ddPCR analysis showed the time interval from detection of plasma T790M to objective progression was 1.1 (0-4.1) months. Compared to 28 patients with rebiopsy showing T790M, the overall survival of 14 patients with T790M detected solely by ddPCR was shorter(41.3 95% CI, 36.6-46.0 vs. 26.6 months 95% CI, 9.9-43.3, respectively).
Plasma ddPCR-based genotyping is a useful technology for detection and monitoring of the key actionable genomic alteration, namely, T790M, in patients treated with gefitinib, erlotinib, or afatinib for activating mutations, to achieve better patient care and outcome.
Stimulation of the NLRP3 inflammasome by metabolic byproducts is known to result in inflammatory responses and metabolic diseases. However, how the host controls aberrant NLRP3 inflammasome ...activation remains unclear. PPARγ, a known regulator of energy metabolism, plays an anti-inflammatory role through the inhibition of NF-κB activation and additionally attenuates NLRP3-dependent IL-1β and IL-18 production. Therefore, we hypothesized that PPARγ serves as an endogenous modulator that attenuates NLRP3 inflammasome activation in macrophages.
Mouse peritoneal macrophages with exposure to a PPARγ agonist at different stages and the NLRP3 inflammasome-reconstituted system in HEK293T cells were used to investigate the additional anti-inflammatory effect of PPARγ on NLRP3 inflammasome regulation. Circulating mononuclear cells of obese patients with weight-loss surgery were used to identify the
correlation between PPARγ and the NLRP3 inflammasome.
Exposure to the PPARγ agonist, rosiglitazone, during the second signal of NLRP3 inflammasome activation attenuated caspase-1 and IL-1β maturation. Moreover, PPARγ interfered with NLRP3 inflammasome formation by decreasing NLRP3-ASC and NLRP3-NLRP3 interactions as well as NLRP3-dependent ASC oligomerization, which is mediated through interaction between the PPARγ DNA-binding domain and the nucleotide-binding and leucine-rich repeat domains of NLRP3. Furthermore, PPARγ was required to limit metabolic damage-associated molecular pattern-induced NLRP3 inflammasome activation in mouse macrophages. Finally, the mature caspase-1/PPARγ ratio was reduced in circulating mononuclear cells of obese patients after weight-loss surgery, which we define as an "NLRP3 accelerating index".
These results revealed an additional anti-inflammatory role for PPARγ in suppressing NLRP3 inflammasome activation through interaction with NLRP3. Thus, our study highlights that PPARγ agonism may be a therapeutic option for targeting NLRP3-related metabolic diseases.
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