Role of mitochondrial stress and the NLRP3 inflammasome in lung diseases.

BACKGROUND: As an organelle essential for intracellular energy supply, mitochondria are involved in intracellular metabolism and inflammation, and cell death. The interaction of mitochondria with the NLRP3 inflammasome in the development of lung diseases has been extensively studied. However, the exact mechanism by which mitochondria mediate the activation of the NLRP3 inflammasome and trigger lung disease is still unclear. METHODS: The literatures related to mitochondrial stress, NLRP3 inflammasome and lung diseases were searched in PubMed. RESULTS: This review aims to provide new insights into the recently discovered mitochondrial regulation of the NLRP3 inflammasome in lung diseases. It also describes the crucial roles of mitochondrial autophagy, long noncoding RNA, micro RNA, altered mitochondrial membrane potential, cell membrane receptors, and ion channels in mitochondrial stress and regulation of the NLRP3 inflammasome, in addition to the reduction of mitochondrial stress by nuclear factor erythroid 2-related factor 2 (Nrf2). The effective components of potential drugs for the treatment of lung diseases under this mechanism are also summarized. CONCLUSION: This review provides a resource for the discovery of new therapeutic mechanisms and suggests ideas for the development of new therapeutic drugs, thus promoting the rapid treatment of lung diseases.

Temperature-dependent persistent luminescence of SrAl2O4:Eu2+, Dy3+, Tb3+: a strategy of optical thermometry avoiding real-time excitation.

A new strategy of optical thermometry is realized by long persistent luminescence phosphor SrAl2O4:Eu2+, Dy3+, Tb3+ (SAEDT). Under different temperatures, SAEDT shows bright afterglow emissions after cessation of the UV excitation. The afterglow color of the SAEDT sample is blue at 60 K and gradually changed into green at 240 K. The normalized afterglow spectra at different temperatures give a dramatic change of fluorescence intensity ratio between the blue band and the green band. Not only has this material exhibited a high absolute sensitivity and relative sensitivity for temperature sensing, but it also has the great advantage of eliminating the heating effect due to avoidance of real-time direct excitation.

Highly uniform and monodisperse ß-NaYF4 : Sm3+ nanoparticles for a nanoscale optical thermometer.

Monodisperse ß-NaYF4:1%Sm3+ nanoparticles were fabricated successfully via the thermal decomposition technique. Strong temperature dependence of the Sm3+ emission was observed when its thermally populated state H7/26 was directly excited to the G5/24 level. This strategy not only can eliminate laser heating and background Stokes-type scattering noise but also has a high quantum yield as a result of one-photon excitation process. Under 594.0 nm laser excitation, the emission intensity of G5/24-H5/26 enhances monotonously with rising temperature from 300 K to 430 K, including a physiological temperature range (27°C-60°C). The relative temperature sensitivity can reach 1.1% K-1 and 0.91% K-1 at 300 K and 330 K, respectively. In addition, the repeatability of temperature sensing was evaluated under several heating-cooling cycles, and the decay curves of the emission at 560.0 nm (G5/24-H5/26) at different temperatures were also investigated. These results raise the prospects of monodisperse ß-NaYF4:1%Sm3+ nanoparticles for optical temperature sensing in biomedicine fields.

Temperature Sensing Using Thermal Population of Low-Lying Energy Levels with (Sm0.01Gd0.99)VO4.

A temperature sensing scheme is proposed that is based on the dramatic temperature dependence of the photoluminescence when Sm3+ dopants are excited from thermally populated 6H7/2,9/2 levels, rather than the ground level 6H5/2, to the 4G5/2 luminescent level. The scheme has the advantage of eliminating laser heating and background Stokes-type scattering noise. Experimental realization was carried out on a (Sm0.01Gd0.99)VO4 sample by detecting the intensities at 550-580 nm using excitation wavelengths of 601.6 nm (process A) and 644.0 nm (process B) to excite Sm3+ to the 4G5/2 level from the 6H7/2 and 6H9/2 levels, which are ca. 1160 and ca. 2270 cm-1 above the ground 6H5/2 level, respectively. The sensitivities achieved are 1267 K/T2 in the temperature range of 183-413 K for process A and 2600 K/T2 in 393-603 K for process B. At even higher temperatures (600-800 K), a complementary process C based on the temperature-dependent luminescence decay lifetime resulted in a relative temperature sensitivity increase from 0.52% K-1 at 640 K to a top value of 3.23% K-1 at around 750 K. Furthermore, factors affecting the temperature dependence of the luminescence intensities have been successfully explored by taking into account the broadening of the thermally activated energy levels and the quantum efficiency of the luminescent level.

Investigation on the site occupation of rare-earth ions in CaIn2O4 with the fluorescence probe of Eu3.

Rare-earth doped CaIn2O4 phosphors have been widely investigated due to their excellent luminescent property, but the site occupation of rare-earth ions in CaIn2O4 is not very clear and needs to be clarified. Using Eu3+ as a fluorescence probe, such a clarification has been made in this work. 1% and 2% Eu3+ doped CaIn2O4 powder samples have been prepared by the sol-gel method. The X-ray diffraction results indicate that the lanthanide doping does not influence the structure of CaIn2O4. Site selective excitation at low temperature disclosed five different luminescent centers marked as A, B, C1, C2 and C3. The spectral analysis revealed that the A and B sites belong to Eu3+ embedded in In3+ sites; the other three are attributed to Eu3+ substitution on Ca2+ sites, which show slight distortion. Energy transfers from the B site to the A and C1 sites were observed in the 2% Eu3+ doped CaIn2O4 sample. The transitions of Eu3+ ions in the Ca2+ sites make the main contribution to the emission spectra excited at room temperature. These results may provide a guide for optimizing rare-earth doped CaIn2O4 phosphors for their application in the solid state lighting field.

Nonlinear Composition-Dependent Optical Spectroscopy of Ba2xSr2-2xV2O7.

In general, adjusting the composition of a fluorescent material is an effective way to tune its luminescent properties such as peak energy and bandwidth. In most solid-solutions, the emission peak shifts linearly with the materials' composition, which is referred to as Vegard's Law. However, we found extraordinary variations in our samples Ba2xSr2-2xV2O7, that is, both the excitation and emission peaks show nonlinear dependence on the composition x, and the same is true for the spectral bandwidths. The nonlinearities are not due to structural anomaly, as all the samples are confirmed to be solid-solutions by X-ray diffraction measurements. To explain these phenomena, we proposed a model by considering the disorder of Ba(2+) and Sr(2+) distributions in solid-solutions and the changes of configurations between the ground and excited electronic states. This novel phenomenon could be applied to further exploit new fluorescent materials.

Temperature sensor based on ladder-level assisted thermal coupling and thermal-enhanced luminescence in NaYF4: Nd³âº.

NaYF4: Nd³âº microprisms were synthesized by a hydrothermal method. The bands of near-infrared (NIR) luminescence originating from the 4F3/2, 4F5/2 and 4F7/2 levels of Nd³âº ions in NaYF4: Nd³âº microcrystals were measured under 574.8 nm excitation at various temperatures from 323 to 673 K. The fluorescence intensity ratios (FIRs) between any two of the three bands change monotonically with temperature and agree with the prediction assuming thermal couplings. A large relative temperature sensitivity of 1.12% K⁻¹ at 500K is reached with the FIR of 4F7/2 to 4F3/2 levels. In addition, anti-Stokes fluorescence from 4F5/2 level (740 nm) and 4F5/2,7/2 levels (740 nm and 803 nm) of Nd³âº ions was studied meticulously under 793.8 nm and 864.2 nm excitations, respectively. The intensities were shown to be greatly enhanced as temperature increases, and the 740 nm band from 4F7/2 level at 458 K increases in intensity by 170 fold relative to that at 298 K under the 793.8 nm excitation.

Strategy for thermometry via Tm³âº-doped NaYF4 core-shell nanoparticles.

Optical thermometers usually make use of the fluorescence intensity ratio of two thermally coupled energy levels, with the relative sensitivity constrained by the limited energy gap. Here we develop a strategy by using the upconversion (UC) emissions originating from two multiplets with opposite temperature dependences to achieve higher relative temperature sensitivity. We show that the intensity ratio of the two UC emissions, ³F(2,3) and ¹G4, of Tm³âº in ß-NaYF4:20%Yb³âº, 0.5%Tm³âº/NaYF4:1%Pr³âº core-shell nanoparticles under 980 nm laser excitation exhibits high relative temperature sensitivity between 350 and 510 K, with a maximum of 1.53% K⁻¹ at 417 K. This demonstrates the validity of the strategy, and that the studied material has the potential for high-performance optical thermometry.

Luminescent properties of LuVO4:Eu3+,Bi3+ red phosphor for light-emitting diodes.

White light-emitting diodes have recently attracted great attention as promising candidates for next-generation lighting. The LuVO4:Eu3+,Bi3+ as new near-ultraviolet excited phosphors were synthesized via high-temperature solid-state reactions. The X-ray diffraction, excitation spectra, emission spectra and decay lifetimes of the phosphors were measured to characterize the structure and luminescent properties. With Bi3+ doping, the edge of excitation band corresponding to the Eu3+ emission shifts from 350 nm to 400 nm with the help of Bi(3+)-V5+ metal-metal charge transfer. Consequently, the phosphor exhibits efficient absorption of near-ultraviolet excitation, and it also exhibits excellent performance in emission intensity compared with the Y2O2S:Eu3+ phosphor in current use. This red-emitting material may be applied as a promising red phosphor for near-ultraviolet excited white light-emitting diodes.

Synthesis and luminescence properties of NaSrPO4:Eu2+, Tb3+, Mn2+ for WLED.

In order to obtain a single-host-white-light phosphor used for near ultraviolet (NUV) light emitting diodes (LEDs), the NaSrPO4:Eu2+, Tb3+, Mn2+ powder samples were synthesized via a high temperature solid-state reaction. XRD investigation shows a single phase. Energy transfer processes is discussed by analyzing the photoluminescence (PL) and photoluminescence excitation (PLE) spectra. White light emitting was observed upon the excitation of a wide range of ultraviolet (UV) wavelengths. The emission spectra are made up of blue, green and red emissions from Eu2+, Tb3+ and Mn2+ ions, respectively. The color shift is insignificant when altering the excitation wavelength from 260 nm to 400 nm. This indicates that the phosphor could exhibit good color stability when used in combination with a NUV LED.

Pr(3+)-doped beta-NaYF4 for temperature sensing with fluorescence intensity ratio technique.

Pure beta-NaYF4:0.8%Pr3+ powder sample was synthesized by the hydrothermal method. The temperature dependence of the fluorescence intensity ratio (FIR) of emission bands corresponding to the 3P1 --> 3H5 and 3P0 --> 3H5 transitions was measured in the temperature range of 120 K to 300 K excited by a 473 nm continuous wave (CW) laser. The dependence of the FIR on temperature is well fitted with an exponential function and the effective energy difference obtained is 457 cm(-1), which gives further an absolute temperature sensitivity of 0.01352 K(-1) at 300 K. The monotonous increase of FIR with temperature and high absolute temperature sensitivity demonstrate that this material can be used as temperature sensor. In addition, mono-dispersed NaYF4:1%Pr3+ nanoparticles were also synthesized.

Local field effect on the photoluminescent spectra of Eu3+ ions in glass.

To investigate the effect of the dielectric medium on the spontaneous emission rate of an isolated emitter, two series of glass samples of various compositions lightly doped with the Eu3+ ion were prepared by melt-quenching method. According to the enhancement factors for emission rates due to the refractive index of the dielectric medium, we qualitatively analyzed the intensities of the electric dipole and magnetic dipole transitions by comparing the emission spectra of the samples with different compositions, viz. various refractive indices. This preliminary result indicates that the local-field effect on the spontaneous emission rates follows the virtual-cavity model, which is derived by assuming that single-ion emitters enter the medium without disturbing the medium, i.e., as interstitial ions or by replacing host ions of low polarizability.

Synthesis and photoluminescent properties of NaYF4:Eu3+ core and NaYF4:Eu3+/NaYF4 core/shell nanocrystals.

NaYF4:Eu3+ core and NaYF4:Eu3+/NaYF4 core/shell nanocrystals (NCs) were synthesized via a wet chemical method. The transmission electron microscope photographs show that the core and core/shell nanoparticles are monodisperse and uniform NCs with average diameters of 22 and 26 nm respectively. The photoluminescence (PL) properties of the samples, including the PL excitation and emission spectra, and luminescent decay curves, are investigated in detail. The results show that the intensity of 5D2 emission relative to that of 5D0 is stronger in NaYF4:Eu3+/NaYF4 core/shell NCs than that in NaYF4:Eu3+ core NCs, and a longer decay lifetime of 5D2 is observed in core/shell samples. In addition, from the corrected emission spectra of 5D0, the 5D0 radiative lifetimes were calculated. These together with the measured decay lifetime of 5D0 emission give the intrinsic quantum yields of 5D0. The results were well interpreted by considering the surface effects.

Research progress of cGAS-STING signaling pathway in intestinal diseases.

The cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) signal has drawn much consideration due to its sensitivity to DNA in innate immune mechanisms. Activation of the cGAS-STIN signaling pathway induces the production of interferon and inflammatory cytokines, resulting in immune responses, or inflammatory diseases. The intestinal tract is a vital organ for the body's nutrition absorption, recent studies have had various points of view on the job of cGAS-STING pathway in various intestinal sicknesses. Therefore, understanding its role and mechanism in the intestinal environment can help to develop new strategies for the treatment of intestinal diseases. This article examines the mechanism of the cGAS-STING pathway and its function in inflammatory bowel disease, intestinal cancer, and long-injury ischemia-reperfusion, lists the current medications that target it for the treatment of intestinal diseases, and discusses the impact of intestinal flora on this signaling pathway, to offer a theoretical and scientific foundation for upcoming targeted therapies for intestinal disorders via the cGAS-STING pathway.

Investigation of the luminescence properties and energy transfer mechanisms in Gd3TaO7:Bi3+,Eu3+ phosphors for their potential application in full-spectrum WLEDs.

In recent years, there has been increasing effort devoted to the development of single-phase white phosphors due to drawbacks such as severe reabsorption and color deviation in traditional white light-emitting diodes (WLEDs). A new feasible strategy has emerged for achieving white light emission through the Bi3+-Eu3+ energy transfer in suitable single-phase phosphors. Therefore, a series of Gd3TaO7:xBi3+ and Gd3TaO7:0.01Bi3+,yEu3+ phosphors were synthesized via a high-temperature solid-state method, and their properties were systematically characterized. In Gd3TaO7, Bi3+ occupies two kinds of Gd3+ site, resulting in two broad emission bands peaking at 427 nm and 500 nm respectively under ultraviolet (UV) excitation, which arise from 3P1 → 1S0 transitions. By adjusting the concentration of Eu3+ in Gd3TaO7:0.01Bi3+,yEu3+, effective energy transfer can occur between Bi3+ and Eu3+, thus enabling the regulation of green-white-red luminescence under 332 nm excitation and blue-white-red luminescence under 365 nm UV light irradiation. Upon stimulation with a 365 nm UV chip, Gd3TaO7:0.01Bi3+,0.02Eu3+ emits white light with CIE coordinates of (0.3509, 0.3202), a color temperature of 4629 K, and an impressive color rendering index of 87.96. The above results indicate the potential of Gd3TaO7:0.01Bi3+,yEu3+ phosphor as a viable candidate for WLED applications.

Thermal imaging study of Sm2+ doped SrB4O7 based on time-resolved technology.

Thermal imaging materials with high sensitivity and the ability to reflect real-time temperature play an important role in research areas such as biotechnology and electronic engineering. However, the temperature sensitivity and temporal resolution of the current materials are not suitable for the complicated detection situation. In this paper, we introduce a thermal imaging material - SrB4O7:5%Sm2+ - with high temperature sensitivity. Furthermore, by applying a time resolving technique based on an intensified charge-coupled device, the sensitivity and temporal resolution are greatly promoted. The good temperature sensitivity (9.67% K-1 at 533 K), the high spatial resolution (2.7 µm) and the fast detection time (<1 s) suggest its considerable potential for real-time thermal imaging applications. The results of temperature distribution on a printed circuit board show that the as-prepared material will be greatly beneficial for thermal imaging applications.

Angelica acutiloba Kitagawa flower induces A549 cell pyroptosis via the NF-κB/NLRP3 pathway for anti-lung cancer effects.

Angelica acutiloba Kitagawa, a traditional medicinal herb of the Umbelliferae family, has been demonstrated to have anticancer activity. In this study, we investigated the anti-lung cancer effects of two compounds extracted from A. acutiloba flowers: kaempferol-3-O-α-L-(4″-E-p-coumaroyl)-rhamnoside (KAE) and platanoside (PLA). MTT, cell colony formation, and cell migration (scratch) assays revealed that both KAE (100 µM) and PLA (50 µM and 100 µM) inhibited the viability, proliferation, and migration of A549 cells. Dichlorodihydrofluorescein diacetate assays showed that KAE and PLA also induced the generation of reactive oxygen species in A549 cells. Morphologically, A549 cells swelled and grew larger under treatment with KAE and PLA, with the most significant changes at 100 µM PLA. Fluorescence staining and measurement of lactate dehydrogenase release showed that the cells underwent pyroptosis with concomitant upregulation of interleukin (IL)-1ß and IL-18. Furthermore, both KAE and PLA induced upregulation of NF-κB, PARP, NLRP3, ASC, cleaved-caspase-1, and GSDMD expression in A549 cells. Subsequent investigations unveiled that these compounds interact with NLRP3, augment NLRP3's binding affinity with ASC, and stimulate the assembly of the inflammasome, thereby inducing pyroptosis. In conclusion, KAE and PLA, two active components of A. acutiloba flower extract, had significant anti-lung cancer activities exerted through regulation of proteins related to the NLRP3 inflammasome pathway.

Ionizable drug delivery systems for efficient and selective gene therapy.

Gene therapy has shown great potential to treat various diseases by repairing the abnormal gene function. However, a great challenge in bringing the nucleic acid formulations to the market is the safe and effective delivery to the specific tissues and cells. To be excited, the development of ionizable drug delivery systems (IDDSs) has promoted a great breakthrough as evidenced by the approval of the BNT162b2 vaccine for prevention of coronavirus disease 2019 (COVID-19) in 2021. Compared with conventional cationic gene vectors, IDDSs can decrease the toxicity of carriers to cell membranes, and increase cellular uptake and endosomal escape of nucleic acids by their unique pH-responsive structures. Despite the progress, there remain necessary requirements for designing more efficient IDDSs for precise gene therapy. Herein, we systematically classify the IDDSs and summarize the characteristics and advantages of IDDSs in order to explore the underlying design mechanisms. The delivery mechanisms and therapeutic applications of IDDSs are comprehensively reviewed for the delivery of pDNA and four kinds of RNA. In particular, organ selecting considerations and high-throughput screening are highlighted to explore efficiently multifunctional ionizable nanomaterials with superior gene delivery capacity. We anticipate providing references for researchers to rationally design more efficient and accurate targeted gene delivery systems in the future, and indicate ideas for developing next generation gene vectors.

Efficient near-infrared quantum cutting in NaYF4: Ho3+, Yb3+ for solar photovoltaics.

Quantum cutting converting a ultraviolet photon into two near-infrared photons has been demonstrated by spectroscopic measurements in NaYF4:Ho3+,Yb3+ synthesized by hydrothermal method. Evidence is provided to confirm the occurrence of quantum cutting. Upon excitation of Ho3+ 5G4 level, near-infrared quantum cutting could occur through a two-step resonance energy transfer from Ho3+ to Yb3+ by cross relaxation, with a maximum quantum efficiency of 155.2%. This result reveals the possibility of violet to near-infrared quantum cutting with a quantum efficiency larger than 100% in Ho3+/Yb3+ codoped fluorides, suggesting the possible application in modifying the solar spectrum to enhance the efficiency of silicon solar cells.

Efficient red-emitting phosphor for near-ultraviolet-based solid-state lighting.

Eu(3+) ion activated Y(2)MoO(6) synthesized by the sol-gel method had been investigated as an alternative red-emitting phosphor for solid-state lighting. Excitation spectra, emission spectra, and decay curves were measured to characterize the luminescent properties. The phosphor shows efficient absorption of near-ultraviolet (NUV) light, and it also exhibits excellent performance in emission intensity and color purity compared with the commercial phosphor in current use. This red-emitting material may be applied as a promising red component for the NUV excited white diode.