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1.
J Am Chem Soc ; 146(11): 7295-7304, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38364093

RESUMEN

All-weather operation is considered an ultimate pursuit of the practical development of sodium-ion batteries (SIBs), however, blocked by a lack of suitable electrolytes at present. Herein, by introducing synergistic manipulation mechanisms driven by phosphorus/silicon involvement, the compact electrode/electrolyte interphases are endowed with improved interfacial Na-ion transport kinetics and desirable structural/thermal stability. Therefore, the modified carbonate-based electrolyte successfully enables all-weather adaptability for long-term operation over a wide temperature range. As a verification, the half-cells using the designed electrolyte operate stably over a temperature range of -25 to 75 °C, accompanied by a capacity retention rate exceeding 70% even after 1700 cycles at 60 °C. More importantly, the full cells assembled with Na3V2(PO4)2O2F cathode and hard carbon anode also have excellent cycling stability, exceeding 500 and 1000 cycles at -25 to 50 °C and superb temperature adaptability during all-weather dynamic testing with continuous temperature change. In short, this work proposes an advanced interfacial regulation strategy targeted at the all-climate SIB operation, which is of good practicability and reference significance.

2.
Connect Tissue Res ; 65(2): 102-116, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38493368

RESUMEN

PURPOSE: Traditionally, the epidural fat (EF) is known as a physical buffer for the dural sac against the force and a lubricant facilitating the relative motion of the latter on the osseous spine. Along with the development of the studies on EF, controversies still exist on vital questions, such as the underlying mechanism of the spinal epidural lipomatosis. Meanwhile, the scattered and fragmented researches hinder the global insight into the seemingly dispensable tissue. METHODS: Herein, we reviewed literature on the EF and its derivatives to elucidate the dynamic change and complex function of EF in the local milieu, especially at the pathophysiological conditions. We start with an introduction to EF and the current pathogenic landscape, emphasizing the interlink between the EF and adjacent structures. We generally categorize the major pathological changes of the EF into hypertrophy, atrophy, and inflammation. RESULTS AND CONCLUSIONS: It is acknowledged that not only the EF (or its cellular components) may be influenced by various endogenic/exogenic and focal/systematic stimuli, but the adjacent structures can also in turn be affected by the EF, which may be a hidden pathogenic clue for specific spinal disease. Meanwhile, the unrevealed sections, which are also the directions the future research, are proposed according to the objective result and rational inference. Further effort should be taken to reveal the underlying mechanism and develop novel therapeutic pathways for the relevant diseases.


Asunto(s)
Espacio Epidural , Lipomatosis , Humanos , Espacio Epidural/patología , Imagen por Resonancia Magnética/métodos , Lipomatosis/patología , Huesos/patología
3.
J Bone Miner Metab ; 42(2): 242-252, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38498197

RESUMEN

INTRODUCTION: This study was to investigate the correlations between pyrethroid exposure and bone mineral density (BMD) and osteopenia. MATERIALS AND METHODS: This cross-sectional study included 1389 participants over 50 years of age drawn from the 2007-2010 and 2013-2014 National Health and Nutrition Examination Survey (NHANES). Three pyrethroid metabolites, 3-phenoxybenzoic acid (3-PBA), trans-3-(2,2-dichlorovinyl)-2,2-dimethyl-cyclopropane-1-carboxylic acid (trans-DCCA), and 4-fluoro-3-phenoxybenzoic acid (4-F-3PBA) were used as indicators of pyrethroid exposure. Low BMD was defined as T-score < - 1.0, including osteopenia. Weighted multivariable linear regression analysis or logistic regression analysis was utilized to evaluate the correlation between pyrethroid exposure and BMD and low BMD. Bayesian kernel machine regression (BKMR) model was utilized to analyze the correlation between pyrethroids mixed exposure and low BMD. RESULTS: There were 648 (48.41%) patients with low BMD. In individual pyrethroid metabolite analysis, both tertile 2 and tertile 3 of trans-DCCA were negatively related to total femur, femur neck, and total spine BMD [coefficient (ß) = - 0.041 to - 0.028; all P < 0.05]. Both tertile 2 and tertile 3 of 4-F-3PBA were negatively related to total femur BMD (P < 0.05). Only tertile 2 [odds ratio (OR) = 1.63; 95% CI = 1.07, 2.48] and tertile 3 (OR = 1.65; 95% CI = 1.10, 2.50) of trans-DCCA was correlated with an increased risk of low BMD. The BKMR analysis indicated that there was a positive tendency between mixed pyrethroids exposure and low BMD. CONCLUSION: In conclusion, pyrethroids exposure was negatively correlated with BMD levels, and the associations of pyrethroids with BMD and low BMD varied by specific pyrethroids, pyrethroid concentrations, and bone sites.


Asunto(s)
Benzoatos , Enfermedades Óseas Metabólicas , Insecticidas , Éteres Fenílicos , Piretrinas , Adulto , Humanos , Persona de Mediana Edad , Piretrinas/efectos adversos , Piretrinas/análisis , Piretrinas/metabolismo , Insecticidas/efectos adversos , Insecticidas/análisis , Insecticidas/metabolismo , Encuestas Nutricionales , Estudios Transversales , Densidad Ósea , Teorema de Bayes , Exposición a Riesgos Ambientales/efectos adversos , Enfermedades Óseas Metabólicas/inducido químicamente , Enfermedades Óseas Metabólicas/epidemiología
4.
J Immunol ; 208(12): 2847-2855, 2022 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-35595309

RESUMEN

Pentraxin-related protein 3 (PTX3), commonly produced by myeloid and endothelial cells, is a humoral pattern recognition protein of the innate immune system. Because PTX3 plasma levels of patients with chronic lymphocytic leukemia (CLL) are high and most circulating cells in patients with CLL are CLL cells, we reasoned that CLL cells produce PTX3. Western immunoblotting revealed that low-density cells from seven of seven patients with CLL produce high levels of PTX3, flow cytometry analysis revealed that the PTX3-producing cells are B lymphocytes coexpressing CD19 and CD5, and confocal microscopy showed that PTX3 is present in the cytoplasm of CLL cells. Because STAT3 is constitutively activated in CLL cells, and because we identified putative STAT3 binding sites within the PTX3 gene promoter, we postulated that phosphorylated STAT3 triggers transcriptional activation of PTX3. Immunoprecipitation analysis of CLL cells' chromatin fragments showed that STAT3 Abs precipitated PTX3 DNA. STAT3 knockdown induced a marked reduction in PTX3 expression, indicating a STAT3-induced transcriptional activation of the PTX3 gene in CLL cells. Using an EMSA, we established and used a dual-reporter luciferase assay to confirm that STAT3 binds the PTX3 gene promoter. Downregulation of PTX3 enhanced apoptosis of CLL cells, suggesting that inhibition of PTX3 might benefit patients with CLL.


Asunto(s)
Proteína C-Reactiva , Leucemia Linfocítica Crónica de Células B , Factor de Transcripción STAT3 , Componente Amiloide P Sérico , Proteína C-Reactiva/genética , Proteína C-Reactiva/metabolismo , Células Endoteliales/metabolismo , Humanos , Factor de Transcripción STAT3/genética , Factor de Transcripción STAT3/metabolismo , Componente Amiloide P Sérico/genética , Componente Amiloide P Sérico/metabolismo
5.
Environ Res ; 260: 119621, 2024 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-39019142

RESUMEN

Atom-dispersed low-coordinated transition metal-Nx catalysts exhibit excellent efficiency in activating peroxydisulfate (PDS) for environmental remediation. However, their catalytic performance is limited due to metal-N coordination number and single-atom loading amount. In this study, low-coordinated nitrogen-doped graphene oxide (GO) confined single-atom Mn catalyst (Mn-SA/NGO) was synthesized by molten salt-assisted pyrolysis and coupled to PDS for degradation of tetracycline (TC) in water. Aberration-corrected high-angle annular dark-field scanning transmission electron microscopy (AC-HAADF-STEM) and X-ray absorption fine structure spectroscopy (XAFS) analysis showed the successful doping of single-atom Mn (weight percentage 1.6%) onto GO and the formation of low-coordinated Mn-N2 sites. The optimized parameters obtained by Box-Behnken Design achieved 100% TC removal in both prediction and experimental results. The Mn-SA/NGO + PDS system had strong anti-interference ability for TC removal in the presence of anions. Besides, Mn-SA/NGO possessed good reusability and stability. O2•-, •OH, and 1O2 were the main active species for TC degradation, and the TC mineralization reached 85.1%. Density functional theory (DFT) calculations confirmed that the introduction of single atoms Mn could effectively enhance adsorption and activation of PDS. The findings provide a reference for the synthesis of high-performance single-atom catalysts for effective removal of antibiotics.


Asunto(s)
Grafito , Sulfatos , Tetraciclina , Contaminantes Químicos del Agua , Grafito/química , Tetraciclina/química , Sulfatos/química , Contaminantes Químicos del Agua/química , Manganeso/química , Nitrógeno/química , Antibacterianos/química , Catálisis
6.
Biol Pharm Bull ; 47(5): 955-964, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38644204

RESUMEN

The occurrence of in-stent restenosis (ISR) poses a significant challenge for percutaneous coronary intervention (PCI). Thus, the promotion of vascular reendothelialization is essential to inhibit endothelial proliferation. In this study, we clarified the mechanism by which Detoxification and Activating Blood Circulation Decoction (DABCD) promotes vascular reendothelialization to avoid ISR by miRNA-126-mediated modulation of the vascular endothelial growth factor (VEGF) signaling pathway. A rat model of post-PCI restenosis was established by balloon injury. The injured aortic segment was collected 14 and 28 d after model establishment. Our findings indicate that on the 14th and 28th days following balloon injury, DABCD reduced intimal hyperplasia and inflammation and promoted vascular reendothelialization. Additionally, DABCD markedly increased nitric oxide (NO) expression and significantly decreased ET-1 production in rat serum. DABCD also increased the mRNA level of endothelial nitric oxide synthase (eNOS) and the protein expression of VEGF, p-Akt, and p-extracellular signal-regulated kinase (ERK)1/2 in vascular tissue. Unexpectedly, the expression of miR-126a-5p mRNA was significantly lower in the aortic tissue of balloon-injured rats than in the aortic tissue of control rats, and higher miR-126a-5p levels were observed in the DABCD groups. The results of this study indicated that the vascular reendothelialization effect of DABCD on arterial intimal injury is associated with the inhibition of neointimal formation and the enhancement of vascular endothelial activity. More specifically, the effects of DABCD were mediated, at least in part, through miR-126-mediated VEGF signaling pathway activation.


Asunto(s)
Medicamentos Herbarios Chinos , MicroARNs , Transducción de Señal , Factor A de Crecimiento Endotelial Vascular , Animales , Masculino , Ratas , Aorta/efectos de los fármacos , Aorta/patología , Aorta/metabolismo , Reestenosis Coronaria/metabolismo , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/uso terapéutico , MicroARNs/efectos de los fármacos , MicroARNs/genética , MicroARNs/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintasa de Tipo III/metabolismo , Ratas Sprague-Dawley , Transducción de Señal/efectos de los fármacos , Factor A de Crecimiento Endotelial Vascular/metabolismo , Factor A de Crecimiento Endotelial Vascular/genética
7.
Appl Opt ; 63(3): 662-667, 2024 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-38294377

RESUMEN

Because chemical gas is sensitive to absorption in the 2 µm band, and 2 µm matches the absorption band of the remote sensing material, many remote sensors and optical sensors are designed to operate in the 2 µm wavelength region. In this paper, we designed an integrated 3 dB power splitter centered at 2 µm. The study of this device is built on a silicon-on-insulator (SOI) platform. We introduced a subwavelength grating (SWG) to improve the performance of the device. We used the three-dimensional finite-difference time-domain (3D FDTD) method to analyze the effect of the structure on the power splitter. The insertion loss (IL) of the fundamental TE mode is only 0.04 dB at 2 µm and its bandwidth of IL <0.45d B is 940 nm (1570-2510 nm). It is suitable for multidomain and all-band photonic integrated circuits at 2 µm.

8.
Ophthalmic Res ; : 1-20, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-39406195

RESUMEN

INTRODUCTION: The splice variant of retinal G-protein-coupled receptor deletion (RGR-d) is a persistent component of drusen and may be involved in the pathogenesis of dry age-related macular degeneration (AMD). Increasing evidence has demonstrated the critical role of autophagy in AMD. In this study, we investigated whether RGR-d disrupts autophagy in early dry AMD in vivo and in vitro. METHODS: Fundus imaging and fluoroscopy were performed on RGR-d mice created by multiplex gene editing. The retina microstructure was evaluated by performing hematoxylin and eosin (H&E) staining as well as transmission electron microscopy (TEM). Retinal function was assessed by full-field electroretinography (ERG). After lentivirus transfection and stimulation, the permeability, phagocytosis, and tight junctions of ARPE-19 cells were evaluated. Western blotting of ATG5, beclin-1, LC3II/I, and P62 was performed to detect the changes in autophagy pathways. RESULTS: Atrophy and patchy penetrating hyperfluorescent foci, consistent with early AMD-like defects, were observed in the fundus of 12-month-old RGR-d mice. H&E staining of retinal tissues indicated thinning of each layer of the retinal structure. H&E staining of retinal tissues indicated thinning of each layer of the retinal structure. TEM analysis showed some diffuse granular deposits. And the morphology of choroidal microvascular endothelial cells was degraded and distorted. The morphology of the photoreceptor outer segments showed structural damage and Bruch's membrane was thickened. ERG indicated that the photoreceptor of RGR-d mice were dysfunctional. Changes in autophagy-related protein expression were observed in the retinal pigment epithelium and retinal neuroepithelium, and autophagy regulation was decreased. Palmitic acid (PA) stimulation caused permeability, phagocytosis, and tight junction dysfunction in cells overexpressing RGR-d. Beclin-1 and LC3II/I expression levels were significantly decreased and that of P62 was elevated in RGR-d cells after PA stimulation. CONCLUSIONS: RGR-d disrupts the autophagy pathway, causing the development of an early AMD-like pathophysiology.

9.
PLoS Genet ; 17(7): e1009649, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34228720

RESUMEN

The differentiation efficiency of adult stem cells undergoes a significant decline in aged animals, which is closely related to the decline in organ function and age-associated diseases. However, the underlying mechanisms that ultimately lead to this observed decline of the differentiation efficiency of stem cells remain largely unclear. This study investigated Drosophila midguts and identified an obvious upregulation of caudal (cad), which encodes a homeobox transcription factor. This factor is traditionally known as a central regulator of embryonic anterior-posterior body axis patterning. This study reports that depletion of cad in intestinal stem/progenitor cells promotes quiescent intestinal stem cells (ISCs) to become activate and produce enterocytes in the midgut under normal gut homeostasis conditions. However, overexpression of cad results in the failure of ISC differentiation and intestinal epithelial regeneration after injury. Moreover, this study suggests that cad prevents intestinal stem/progenitor cell differentiation by modulating the Janus kinase/signal transducers and activators of the transcription pathway and Sox21a-GATAe signaling cascade. Importantly, the reduction of cad expression in intestinal stem/progenitor cells restrained age-associated gut hyperplasia in Drosophila. This study identified a function of the homeobox gene cad in the modulation of adult stem cell differentiation and suggested a potential gene target for the treatment of age-related diseases induced by age-related stem cell dysfunction.


Asunto(s)
Células Madre Adultas/metabolismo , Diferenciación Celular/genética , Proteínas de Drosophila/metabolismo , Proteínas de Homeodominio/metabolismo , Factores de Transcripción/metabolismo , Células Madre Adultas/fisiología , Factores de Edad , Envejecimiento/genética , Envejecimiento/fisiología , Animales , Diferenciación Celular/fisiología , Proliferación Celular/genética , Proteínas de Drosophila/genética , Drosophila melanogaster/metabolismo , Expresión Génica/genética , Regulación de la Expresión Génica/genética , Genes Homeobox/genética , Proteínas de Homeodominio/genética , Mucosa Intestinal/metabolismo , Intestinos/citología , Quinasas Janus/genética , Transducción de Señal/genética , Factores de Transcripción/genética
10.
Phytother Res ; 38(5): 2496-2517, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38447978

RESUMEN

We investigated the mechanism by which quercetin preserves mitochondrial quality control (MQC) in cardiomyocytes subjected to ischemia-reperfusion stress. An enzyme-linked immunosorbent assay was employed in the in vivo experiments to assess myocardial injury markers, measure the transcript levels of SIRT5/DNAPK-cs/MLKL during various time intervals of ischemia-reperfusion, and observe structural changes in cardiomyocytes using transmission electron microscopy. In in vitro investigations, adenovirus transfection was employed to establish a gene-modified model of DNA-PKcs, and primary cardiomyocytes were obtained from a mouse model with modified SIRT5 gene. Reverse transcription polymerase chain reaction, laser confocal microscopy, immunofluorescence localization, JC-1 fluorescence assay, Seahorse energy analysis, and various other assays were applied to corroborate the regulatory influence of quercetin on the MQC network in cardiomyocytes after ischemia-reperfusion. In vitro experiments demonstrated that ischemia-reperfusion injury caused changes in the structure of the myocardium. It was seen that quercetin had a beneficial effect on the myocardial tissue, providing protection. As the ischemia-reperfusion process continued, the levels of DNA-PKcs/SIRT5/MLKL transcripts were also found to change. In vitro investigations revealed that quercetin mitigated cardiomyocyte injury caused by mitochondrial oxidative stress through DNA-PKcs, and regulated mitophagy and mitochondrial kinetics to sustain optimal mitochondrial energy metabolism levels. Quercetin, through SIRT5 desuccinylation, modulated the stability of DNA-PKcs, and together they regulated the "mitophagy-unfolded protein response." This preserved the integrity of mitochondrial membrane and genome, mitochondrial dynamics, and mitochondrial energy metabolism. Quercetin may operate synergistically to oversee the regulation of mitophagy and the unfolded protein response through DNA-PKcs-SIRT5 interaction.


Asunto(s)
Miocitos Cardíacos , Quercetina , Sirtuinas , Quercetina/farmacología , Animales , Miocitos Cardíacos/efectos de los fármacos , Miocitos Cardíacos/metabolismo , Ratones , Sirtuinas/metabolismo , Daño por Reperfusión Miocárdica/tratamiento farmacológico , Daño por Reperfusión Miocárdica/metabolismo , Estrés Oxidativo/efectos de los fármacos , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Proteína Quinasa Activada por ADN/metabolismo , Masculino , Ratones Endogámicos C57BL , Mitofagia/efectos de los fármacos
11.
Nano Lett ; 23(18): 8761-8769, 2023 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-37695577

RESUMEN

Metal-organic framework-based metal ion therapy has attracted increasing attention to promote the cascade wound-healing process. However, multimetal ion synergistic administration and accurately controlled ion release are still the challenges. Herein, an aptamer-functionalized silver@cupriferous Prussian blue (ACPA) is established as a metal-based theranostic nanoagent for a chronic nonhealing diabetic wound treatment. Prussian blue offers a programmable nanoplatform to formulate metal ion prescriptions, achieving cooperative wound healing. Silver, copper, and iron ions are released from ACPA controlled by the near-infrared-triggered mild hyperthermia and then synergistically participate in antipathogen, cell migration, and revascularization. ACPA also demonstrates a unique core-satellite nanostructure which enables it with improved surface-enhanced Raman scattering (SERS) capability as potent bacteria-targeted Raman-silent nanoprobe to monitor the residual bacteria during wound healing with nearly zero background. The theranostic feature of ACPA allows high-performance SERS imaging-guided chronic wound healing in infectious diabetic skin and keratitis.

12.
Int J Mol Sci ; 25(5)2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38473792

RESUMEN

Lindera erythrocarpa, a flowering plant native to eastern Asia, has been reported to have neuroprotective activity. However, reports on the specific bioactive compounds in L. erythrocarpa are finite. The aim of this study was to investigate the anti-neuroinflammatory and neuroprotective effects of the compounds isolated from L. erythrocarpa. Dihydropashanone, a compound isolated from L. erythrocarpa extract, was found to have protected mouse hippocampus HT22 cells from glutamate-induced cell death. The antioxidant and anti-inflammatory properties of dihydropashanone in mouse microglial BV2 and HT22 cells were explored in this study. The results reveal that dihydropashanone inhibits lipopolysaccharide-induced inflammatory response and suppresses the activation of nuclear factor (NF)-κB in BV2 cells. In addition, dihydropashanone reduced the buildup of reactive oxygen species in HT22 cells and induced activation of the nuclear factor E2-related factor 2 (Nrf2)/heme oxygenase (HO)-1 signaling pathway in BV2 and HT22 cells. Our results suggest that dihydropashanone reduces neuroinflammation by decreasing NF-κB activation in microglia cells and protects neurons from oxidative stress via the activation of the Nrf2/HO-1 pathway. Thus, our data suggest that dihydropashanone offers a broad range of applications in the treatment of neurodegenerative illnesses.


Asunto(s)
Lindera , Enfermedades Neurodegenerativas , Ratones , Animales , Lindera/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Transducción de Señal , Antiinflamatorios/farmacología , FN-kappa B/metabolismo
13.
Int J Mol Sci ; 25(6)2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38542316

RESUMEN

Nardostachys jatamansi is widely used as a traditional medicine in Asian countries. Numerous recent studies have reported the biological activities of its secondary metabolites and extracts. In this study, a total of 14 components were isolated, including cycloolivil and 2-(3'-hydroxy-5'-ethoxyphenyl)-3-hydroxylmethyl-7-methoxy-2,3-dihydrobenzofuran-5-carboxylic acid, which were first discovered in N. jatamansi. The isolated compounds were investigated for their anti-inflammatory effects on HaCaT keratinocytes and their potential to alleviate skin inflammation. The results of the screening revealed that cycloolivil and 4ß-hydroxy-8ß-methoxy-10-methylene-2,9-dioxatricyclo[4.3.1.03,7]decane reduced the production of inflammatory cytokines induced by TNF-α/IFN-γ, such as IL-6, IL-8, and RANTES, in keratinocytes. This study focused on exploring the biological effects of cycloolivil, and the results suggested that cycloolivil inhibits the expression of COX-2 proteins. Further mechanistic evaluations confirmed that the anti-inflammatory effects of cycloolivil were mediated by blockage of the NF-κB and JAK/STAT signaling pathways. These results suggest that cycloolivil isolated from N. jatamansi could be used to treat skin inflammatory diseases.


Asunto(s)
FN-kappa B , Nardostachys , Fenoles , FN-kappa B/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Nardostachys/metabolismo , Interferón gamma/metabolismo , Queratinocitos/metabolismo , Antiinflamatorios/farmacología , Antiinflamatorios/metabolismo
14.
Phys Rev Lett ; 130(15): 153801, 2023 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-37115872

RESUMEN

Bound states of solitons ("molecules") occur in various settings, playing an important role in the operation of fiber lasers, optical emulation, encoding, and communications. Soliton interactions are generally related to breathing dynamics in nonlinear dissipative systems, and maintain potential applications in spectroscopy. In the present work, dichromatic breather molecules (DBMs) are created in a synchronized mode-locked fiber laser. Real-time delay-shifting interference spectra are measured to display the temporal evolution of the DBMs, that cannot be observed by means of the usual real-time spectroscopy. As a result, robust out-of-phase vibrations are found as a typical intrinsic mode of DBMs. The same bound states are produced numerically in the framework of a model combining equations for the population inversion in the mode-locked laser and cross-phase-modulation-coupled complex Ginzburg-Landau equations for amplitudes of the optical fields in the fiber segments of the laser cavity. The results demonstrate that the Q-switching instability induces the onset of breathing oscillations. The findings offer new possibilities for the design of various regimes of the operation of ultrafast lasers.

15.
Environ Sci Technol ; 57(51): 21866-21875, 2023 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-38095886

RESUMEN

Vanadium-based catalysts play a pivotal role in the emission control of industrial NOx via selective catalytic reduction (SCR) technology. However, little attention has been paid to the potential emission of greenhouse gas N2O under complex working conditions. This work reports that a commercial V2O5/TiO2 catalyst may lead to significant N2O emission without greatly changing the outlet NOx concentration after chromium (Cr) deposition. With a Cr loading of 2 wt %, N2O concentration increased from 27.8 to 199.2 ppm at 350 °C with the value of outlet N2O/(N2O+N2) from 2.5% to 19.4%. Experimental results combined with DFT+U calculations suggest that nonselective catalytic reduction (NSCR) is the main route for N2O formation in a wide temperature range of 250 ∼ 400 °C. It is stemmed from the fact that the covalent interaction between Cr and V species on the V2O5/TiO2 surface accelerates the conversion of V4+ + Cr6+ → V5+ + Cr3+, leading to a larger proportion of surface V5+. More importantly, surface V5+ is highly related to the redox property of the V2O5/TiO2 catalyst, which is beneficial to NSCR reaction rather than the standard SCR process. The work suggests that to better inhibit the emission of greenhouse gases during the NH3-SCR process, monitoring N2O emission should be included along with the NOx concentrations, especially in complex flue gases.


Asunto(s)
Gases de Efecto Invernadero , Titanio , Óxidos de Nitrógeno , Oxidación-Reducción , Catálisis , Gases , Amoníaco
16.
Environ Res ; 227: 115752, 2023 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-36965812

RESUMEN

The conventional Fenton process has the drawbacks of low efficiency of Fe3+/Fe2+ conversion, low utilization of H2O2, and narrow range of pH. In this paper, molybdenum sulfide (MoS2) was used as a co-catalyst to boost the nanoscale zero-valent iron (nZVI) based heterogeneous Fenton-like process for the degradation of Rhodamine B (RhB). The catalytic performance, influences of parameters, degradation mechanism, and toxicity of intermediates were explored. Compared with the conventional like-Fenton process, the existence of MoS2 accelerated the decomposition of H2O2 and the RhB degradation rate constant of MoS2/nZVI/H2O2 reached more than six times that of nZVI/H2O2. In addition, the effective pH range of MoS2/nZVI/H2O2 was broadened to 9.0 with 84.9% of RhB being removed within 15 min. The co-catalytic system of MoS2 and nZVI was stable and had high reusability according to the results of four consecutive runs. Quenching tests and electron paramagnetic resonance (EPR) demonstrated that hydroxyl radical (·OH), superoxide anions (·O2-), and singlet oxygen (1O2) were all involved in MoS2/nZVI/H2O2. Compared with nZVI/H2O2 system, MoS2 not only increased the corrosion of nZVI but also accelerated the conversion of Fe3+/Fe2+. ECOSAR analysis suggested that the overall acute and chronic toxicity of the degradation products decreased after treatment. Hence, this MoS2 co-catalytic nZVI based Fenton-like process can be used as a promising alternative for the treatment of organic wastewater.


Asunto(s)
Hierro , Contaminantes Químicos del Agua , Hierro/química , Molibdeno , Peróxido de Hidrógeno/química , Contaminantes Químicos del Agua/análisis , Catálisis
17.
Environ Res ; 231(Pt 1): 116080, 2023 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-37164285

RESUMEN

Biochar derived from bamboo was used to support sulfide nanoscale zero-valent iron (S-nZVI@BC) for simultaneous removal of Cd(II) and As (III) from aqueous media. Scanning electron microscopy (SEM) and X-ray diffraction spectroscopy (XRD) characterization confirmed the successful synthesis of the S-nZVI@BC. Adsorption kinetics and isotherms indicated that co-adsorption of Cd(II) and As(III) onto S-nZVI@BC was well represented by pseudo-second-order model (R2Cd(II) = 0.990, R2As(III) = 0.995) and Langmuir model (R2Cd(II) = 0.954, R2As(III) = 0.936). The maximum adsorption was 162.365 and 276.133 mg/g for Cd(II) and As(III), respectively, in a co-adsorption system, which was significantly higher than that in a single adsorption system (103.195 and 223.736 mg/g, respectively). Batch experiments showed that the Cd(II)-to-As(III) concentration ratio significantly affected the co-adsorption with the optimal ratio of 1:2. Ca2+ and Mg2+ significantly inhibited Cd(II) removal. In contrast, phosphate and humic acid significantly inhibited As(III) removal. Electrochemical analysis indicated S-nZVI@BC had a lower corrosion potential and resistance than nZVI@BC, making it more conducive to electron transfer and chemical reaction. Electrostatic adsorption, complexation, co-precipitation, and redox were the primary mechanisms for Cd(II) and As(III) removal. Overall, the present study provides new insights into the synergistic removal of Cd(II) and As(III) by S-nZVI@BC, which is a very promising adsorbent for the effective removal of Cd(II) and As(III) from contaminated wastewater.


Asunto(s)
Hierro , Contaminantes Químicos del Agua , Hierro/química , Cadmio/análisis , Adsorción , Contaminantes Químicos del Agua/análisis
18.
Eur Spine J ; 32(11): 4054-4062, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37674057

RESUMEN

PURPOSE: The aim of this study was to assess the clinical efficacy of balanced halo-pelvic traction (HPT) and evaluate its contribution to the correction surgery in treating adult severe rigid spinal deformity. METHODS: One hundred and eight adult patients with severe rigid spinal deformity who underwent preoperative HPT and correction surgery were reviewed. The main coronal curve, segmental kyphotic angle, coronal balance (CB), sagittal balance (SVA), and the length of spine were measured before HPT, after HPT, post-operatively, and at final follow-up. The HPT contribution rates to deformity correction were calculated. RESULTS: The pre-HPT main coronal curve was 103.4 ± 10.6°, improved to 61.0 ± 13.4° after traction and further improved to 44.2 ± 10.2° after surgical correction, and maintained at 50.3 ± 9.9° at final follow-up. CB started at 4.2 ± 4.8 cm, improved to 2.1 ± 2.5 cm after HPT, 0.8 ± 1.2 cm after operation, and 0.7 ± 0.9 cm at final follow-up. The pre-HPT sagittal segmental kyphotic angle was 67.3 ± 17.7°, was then improved to 42.2 ± 27.5° after traction and further improved to 34.9 ± 10.2° after surgery, and maintained at 35.4 ± 10.4° at final follow-up. The length of spine improved from 35.9 ± 5.9 to 42.6 ± 6.0 cm via HPT, reached up to 45.0 ± 6.0 cm after operation, and maintained at 44.3 ± 5.2 cm at final follow-up. CONCLUSION: HPT is effective for the treatment of severe rigid spinal deformity. Balanced HPT can dramatically improve coronal and sagittal deformity as well as spinal length before corrective surgery.


Asunto(s)
Cifosis , Escoliosis , Fusión Vertebral , Adulto , Humanos , Escoliosis/cirugía , Tracción , Estudios Retrospectivos , Columna Vertebral/diagnóstico por imagen , Columna Vertebral/cirugía , Cifosis/diagnóstico por imagen , Cifosis/cirugía , Resultado del Tratamiento
19.
Nano Lett ; 22(12): 4741-4749, 2022 06 22.
Artículo en Inglés | MEDLINE | ID: mdl-35623050

RESUMEN

Photothermal therapy (PTT) in the second near-infrared (NIR-II) window has emerged as a better candidate for deep-tissue tumor elimination. More interestingly, the photothermal ablated tumor cells also manifest somewhat immunostimulation potency to elicit antitumor immunity, although most dying cells are undergoing apoptosis that is commonly considered as immunologically silent. Here, a NIR-II responsive nanosystem is established for tumor photoimmunotherapy using molybdenum dioxide (MoO2) nanodumbbells as the nanoconverter. Meanwhile, an apoptosis-blocking strategy is proposed to regulate the cell death pattern under NIR-II laser irradiation in order to improve the immunogenic cell death. The nanoformulation can efficiently block caspase 8-dependent apoptotic pathway in photothermal ablated tumor cells and transform into more immunogenic death patterns, thereby activating systemic immunity to inhibit tumor growth and metastasis. In addition, this strategy also helps enhance the body's responses to α-PD-1 immune checkpoint inhibitor, which implies a potential optimal combination for cancer immunotherapy.


Asunto(s)
Nanopartículas , Neoplasias , Línea Celular Tumoral , Humanos , Inmunoterapia , Molibdeno , Nanopartículas/uso terapéutico , Neoplasias/terapia , Óxidos , Fototerapia
20.
Int J Mol Sci ; 24(8)2023 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-37108534

RESUMEN

Skin is the first line of defense in the body against external stimulation and injury. Inflammation and oxidative stress in skin cells are the initiators and promoters of several skin diseases. Latifolin is a natural flavonoid isolated from Dalbergia odorifera T. Chen. This study aimed to evaluate the anti-inflammatory and antioxidant properties of latifolin. The anti-inflammatory effects were evaluated using tumor necrosis factor-α/interferon-γ (TNF-α/IFN-γ)-treated HaCaT cells, revealing that latifolin inhibited the secretion of Interleukin 6 (IL-6); Interleukin 8 (IL-8); Regulated upon Activation, Normal T Cell Expressed and Presumably Secreted (RANTES); and Macrophage-derived chemokine (MDC) while decreasing the expression of Intercellular Adhesion Molecule 1 (ICAM-1). The results of western blots and immunofluorescence demonstrated that the activation of Janus kinase 2 (JAK2), Signal transducer and activator of transcription 1 (STAT1), Signal transducer and activator of transcription 3 (STAT3), and nuclear factor kappa-light-chain-enhancer of activated B (NF-κB) cells signaling pathways were significantly inhibited by latifolin. The antioxidant properties were evaluated using t-BHP-induced BJ-5ta cells. Latifolin increased the viability of t-BHP-induced BJ-5ta cells. Additionally, fluorescent staining of reactive oxygen species (ROS) showed that the production of ROS was inhibited by latifolin. Additionally, latifolin reduced the phosphorylation of p38 and JNK. The results indicate that latifolin has potential anti-inflammatory and antioxidant properties, and may be a candidate natural compound for the treatment of skin diseases.


Asunto(s)
Dalbergia , Especies Reactivas de Oxígeno/metabolismo , Antioxidantes/farmacología , Antioxidantes/metabolismo , Línea Celular , Queratinocitos/metabolismo , Antiinflamatorios/farmacología , Antiinflamatorios/metabolismo , FN-kappa B/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo
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