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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 325: 125012, 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39236573

RESUMEN

Lipid droplets (LDs) serve as vital subcellular organelles, crucial for the maintenance of lipid and energy homeostasis within cells. Their visualization is of significant value for elucidating the intricate interactions between LDs and other cellular organelles. Despite the importance of LDs, the literature on the utilization of phthalocyanine-based photosensitizers for targeted LD imaging and two-photon imaging-guided photodynamic therapy (PDT) remains sparse. In this study, we have designed and synthesized trifluoromethyl-pyrrolidone silicon phthalocyanine (PyCF3SiPc). To enhance the water solubility of PyCF3SiPc and improve its tumor cells accumulation, we employed 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy(poly(ethylene glycol))-2000] (DSPE-mPEG2000) as a nanocarrier, thereby formulating DSPE@PyCF3SiPc nanoparticles. Our in vitro experiments in MCF-7 cells demonstrated that DSPE@PyCF3SiPc selectively targets and visualizes LDs, offering a reliable tool for tracking their dynamic movement. Moreover, DSPE@PyCF3SiPc demonstrates considerable phototoxicity against MCF-7 cells subjected to PDT underscoring its potential as an effective therapeutic agent. In conclusion, DSPE@PyCF3SiPc presents itself as a promising novel probe for the dual purpose of monitoring the dynamic movement of LDs and guiding imaging-assisted PDT. The development of this nanoparticle system not only advances our understanding of LD biology but also paves the way for innovative therapeutic strategies in oncology.

2.
Lipids Health Dis ; 23(1): 252, 2024 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-39154165

RESUMEN

OBJECTIVE: The present study examined the ability of the body roundness index (BRI) to predict the incidence of diabetes and prediabetes among adults in the USA. METHOD: The study enrolled 11,980 adults aged ≥ 20 years from the National Health and Nutrition Examination Survey (NHANES). Logistic regression served as the primary method for analyzing the relevant link between BRI and the incidence of diabetes and prediabetes, including univariate analysis, multivariate regression analysis, smooth curve fitting analysis, and subgroup analysis. What's more, receiver operating characteristic (ROC) analysis was applied to confirm the predictive values of BRI for diabetes and prediabetes. RESULTS: Each unit higher than BRI was associated with a 17% increased risk of diabetes and prediabetes after covariate adjustments (OR: 1.17, 95% CI: 1.07-1.27). Those with BRI in the high scores (Q4) possessed an increased likelihood of having diabetes and prediabetes than individuals in the reference group (OR: 1.83, 95% CI: 1.29-2.58). A smooth curve fitting analysis revealed a non-linear trend. The results across all population subgroups were uniform to those of the total population. The ROC curve indicated that the BRI was the best predictor of diabetes and prediabetes among other anthropometric indices. CONCLUSIONS: Diabetes and prediabetes occurrence rates and BRI have a positive and non-linear relationship in American adults. The BRI indices could function as predictive markers for diabetes and prediabetes.


Asunto(s)
Encuestas Nutricionales , Estado Prediabético , Humanos , Estado Prediabético/epidemiología , Estado Prediabético/diagnóstico , Femenino , Masculino , Adulto , Persona de Mediana Edad , Estudios Transversales , Estados Unidos/epidemiología , Diabetes Mellitus/epidemiología , Curva ROC , Índice de Masa Corporal , Factores de Riesgo , Anciano , Modelos Logísticos
3.
Dalton Trans ; 53(34): 14289-14299, 2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39133266

RESUMEN

In recent years, with the growing demand for non-contact and real-time optical temperature measurements, it has become imperative to develop new luminescent thermometry materials as well as novel temperature detection schemes with higher sensitivity. In this work, a series of Sr1-xB4O7:xTm2+ (x = 0.001-0.01) polycrystalline powder samples were prepared using a high temperature solid state reaction under ambient atmospheric conditions. The emission spectra and the luminescence decay curves of the red emission corresponding to the 4f125d → 4f13(2F7/2) transition of Tm2+ were recorded at intervals of 10 K from 280 K to 380 K. Both the emission intensity and the fluorescence lifetime exhibited remarkable temperature correlation in the studied temperature range, which reached the best relative temperature sensitivities of 3.55% K-1 and 3.86% K-1 at 363 K and 346 K, respectively. Furthermore, taking into account the highly sensitive variation of the fluorescence lifetime of Tm2+ in the SrB4O7 matrix as the temperature increased near room temperature, a time-resolved temperature measurement scheme was performed to realize real-time temperature field imaging. By utilizing the intensified charge coupled device (ICCD) camera with a time gate to acquire the integral intensity of distinct time intervals and calibrate the relationship between the ratio and the temperature, the experimental results demonstrated that this temperature measurement scheme can achieve a maximum relative sensitivity of 9.39% K-1 at 313 K, which significantly surpasses the relative sensitivity of the other two conventional temperature measurement schemes.

4.
Mikrochim Acta ; 191(4): 205, 2024 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-38492087

RESUMEN

A simple and cost-effective fabrication method of gold nanorods (AuNRs) nanoparticles hybridized with polyvinyl alcohol hydrogel (AuNR/PVA) for SERS substrate is described. The AuNR/PVA achieves the control of inter-particle nanogap by modulating the density of gold nanorods, and inter-particle nanogap by the spatial deformation of the hydrogel, and the reduction of the gap between the AuNRs deposited on hydrogel makes the SERS enhancement. In addition, the AuNR/PVA substrate maintains high SERS activity after more than 100 cycles of bending and storage in air for 30 days, and the substrate possesses high sensitivity and high reproducibility. Combining a flexible and transparent surface-enhanced Raman spectroscopy (SERS) substrate for in situ detection with a small portable Raman can be applied to scenarios such as environmental detection and hazardous materials detection. The substrate showed excellent SERS activity against malachite green (MG) and crystal violet (CV) with limits of detection of 1.18 × 10-13 M and 7.17 × 10-12 M, respectively. The usability of the proposed SERS substrate was demonstrated by detecting the above contaminants in aquatic water. This work not only utilizes a cost-effective method for mass production but also provides a reliable and convenient platform for the preparation of other noble metal flexible substrates.

5.
J Chem Phys ; 160(9)2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38441503

RESUMEN

In view of the inherent pseudocapacitance, rich redox pairs (Nb5+/Nb4+ and Nb4+/Nb3+), and high lithiation potential (1.0-3.0 V vs Li/Li+), Nb2O5 is considered a promising anode material. However, the inherent low electronic conductivity of Nb2O5 limits its lithium storage performance, and the rate performance after carbon modification is still unsatisfactory because the intrinsic conductivity of Nb2O5 has not been substantially improved. In this experiment, taking the improvement of the intrinsic electrical conductivity of Nb2O5 as the guiding ideology, we prepared F-doped Nb2O5@fluorocarbon composites (F-Nb2O5@FC) with a large number of oxygen vacancies by one-step annealing. As the anode electrode of lithium-ion batteries, the reversible specific capacity of F-Nb2O5@FC reaches 150 mA g-1 at 5 A g-1 after 1100 cycles, and the rate performance is particularly outstanding, with a capacity up to 130 mA g-1 at 16 A g-1, which is far superior to other Nb2O5@carbon-based anode electrodes. Compared with other single conductivity sources of Nb2O5@carbon-based composites, the electrical conductivity of F-Nb2O5@FC composites is greatly improved in many aspects, including the introduction of free electrons by F- doping, the generation of oxygen vacancies, and the provision of a three-dimensional conductive network by FC. Through analytical chemistry (work function, UV-Vis diffuse reflectance spectroscopy, and EIS) and theoretical calculations, it is proved that F-Nb2O5@FC has high electrical conductivity and realizes rapid electron transfer.

6.
Environ Sci Pollut Res Int ; 31(7): 11334-11348, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38217819

RESUMEN

The grey water footprint (GWF) is an advanced index linking pollution load and water resources. However, the existing agriculture-related GWF was developed based on hydrological processes, which limits its role in watershed water pollution level (WPL) measurements. The main scope of this study is to calculate GWF and WPL based on runoff, total nitrogen (TN), and total phosphorus (TP) observations in the Hujiashan Watershed of China's Yangtze River Basin. Partial least squares structural equation modeling (PLS-SEM) was utilized to explore the impact pathways of environmental features on GWF and WPL. On this basis, propose measures for the management of this agricultural watershed. The results showed that the TN concentration had a V-shaped trend in 2008-2015, while the TP gradually decreased. The GWF calculations for the TN and TP were compatible with the temporal trends for the concentrations, which were higher in the wet season (0.45 m3/m2 for TN, 0.10 m3/m2 for TP) than in the dry season (0.11 m3/m2 for TN, 0.02 m3/m2 for TP) and increased from upstream to downstream. The WPLs of TN exceeded 2.0 in the midstream and downstream areas, whereas those for TP were inconspicuous. According to PLS-SEM, the GWF is primarily influenced by topographical variables and hydrological features, whereas the WPL is mainly controlled by hydrological features and landscape composition. Fertilizer reduction and efficiency measures should be implemented on farmland and appropriately reducing farming activities on slopes to relieve the GWF and WPL in the watershed.


Asunto(s)
Contaminantes Químicos del Agua , Agua , Monitoreo del Ambiente/métodos , Contaminantes Químicos del Agua/análisis , Contaminación del Agua/análisis , Agricultura , Nitrógeno/análisis , Fósforo/análisis , China
7.
Mikrochim Acta ; 191(1): 41, 2023 12 19.
Artículo en Inglés | MEDLINE | ID: mdl-38112843

RESUMEN

A highly sensitive tumor necrosis factor α (TNF-α) detection method based on a surface-enhanced Raman scattering (SERS) magnetic patch sensor is reported. Magnetic beads (MNPs) and core shells were used as the capture matrix and signaling probe, respectively. For this purpose, antibodies were immobilized on the surface of magnetic beads, and then Au@4-MBN@Ag core-shell structures coupled with aptamers and TNF-α antigen were added sequentially to form a sandwich immune complex. Quantitative analysis was performed by monitoring changes in the characteristic SERS signal intensity of the Raman reporter molecule 4-MBN. The results showed that the limit of detection (LOD) of the proposed method was 4.37 × 10-15 mg·mL-1 with good linearity (R2 = 0.9918) over the concentration range 10-12 to 10-5 mg·mL-1. Excellent assay accuracy was also demonstrated, with recoveries in the range 102% to 114%. Since all reactions occur in solution and are separated by magnetic adsorption of magnetic beads, this SERS-based immunoassay technique solves the kinetic problems of limited diffusion and difficult separation on solid substrates. The method is therefore expected to be a good clinical tool for the diagnosis of the inflammatory biomarker THF-α and in vivo inflammation screening.


Asunto(s)
Aptámeros de Nucleótidos , Factor de Necrosis Tumoral alfa , Plata/química , Oro/química , Magnetismo , Aptámeros de Nucleótidos/química
8.
Dalton Trans ; 52(35): 12504-12516, 2023 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-37605932

RESUMEN

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.

9.
Front Endocrinol (Lausanne) ; 13: 999702, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36157474

RESUMEN

Objective: To investigate the effect of multiple eHealth-delivered lifestyle interventions on obesity-related anthropometric outcomes in children and adolescents. Methods: The Medline (via PubMed), Embase, Cochrane Library, Web of Science, CBM, VIP, CNKI, and Wanfang electronic databases were systematically searched from their inception to March 18, 2022, for randomized controlled trials (RCTs). Meta-analyses were performed to investigate the effect of multiple eHealth-delivered lifestyle interventions on obesity-related anthropometric outcomes (body mass index [BMI], BMI Z-score, waist circumference, body weight, and body fat%). Two independent investigators reviewed the studies for accuracy and completeness. All included studies were evaluated using the Cochrane Risk-of-Bias (ROB) Tool. Results: Forty trials comprising 6,403 patients were selected for the meta-analysis. The eligible trials were published from 2006 to 2022. Compared with the control group, the eHealth-intervention group was more effective in reducing BMI (weighted mean difference [WMD] = -0.32, 95% confidence interval [CI]: -0.50 to -0.13, I2 = 85.9%), BMI Z-score (WMD = -0.08, 95% CI: -0.14 to -0.03, I2 = 89.1%), waist circumference (WMD = -0.87, 95% CI: -1.70 to -0.04, I2 = 43.3%), body weight (WMD = -0.96, 95% CI: -1.55 to -0.37, I2 = 0.0%), and body fat% (WMD = -0.59, 95% CI: -1.08 to -0.10, I2 = 0.0%). The subgroup analysis showed that parental or school involvement (WMD = -0.66, 95% CI: -0.98 to -0.34), eHealth-intervention duration of >12 weeks (WMD = -0.67, 95% CI: -0.96 to -0.38), and mobile-based interventions (WMD = -0.78, 95% CI: -1.13 to -0.43) had a significantly greater intervention effect size on BMI. Conclusions: This review recommends that multiple eHealth-delivered lifestyle strategies may be useful for preventing or treating overweight and obesity among children and adolescents. However, our results should be cautiously interpreted due to certain limitations in our study.


Asunto(s)
Obesidad Infantil , Telemedicina , Adolescente , Peso Corporal , Niño , Humanos , Estilo de Vida , Sobrepeso/prevención & control , Obesidad Infantil/prevención & control
10.
Dalton Trans ; 50(23): 8144-8153, 2021 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-34028479

RESUMEN

Recently, using the Eu2+ → Mn2+ energy transfer strategy to explore new single-phase phosphors suitable for the near-ultraviolet (n-UV) region has become one of the major strategies in solid-state lighting applications. Therefore, a novel color-tunable K2BaCa(PO4)2 (KBCPO):[Eu2+,Si4+],Mn2+ phosphor was developed because of the preeminent thermal stability of luminescence of Eu2+-activated KBCPO. In this study, we first designed a [Eu2+, Si4+] → [K+, P5+] charge compensation strategy to optimize the luminescence properties of Eu2+ in the KBCPO matrix. In terms of the obtained KBCPO:[Eu2+,Si4+] phosphor, this charge compensation method on the one hand strengthens the emission of Eu2+, and on the other hand, it dramatically improves the thermal stability of luminescence. In particular, the emission intensity of the KBCPO:0.03[Eu2+,Si4+] sample at 548 K can reach 103% relative to that at the initial temperature of 298 K. Based on this charge compensation strategy, we finally obtained a new dual emission KBCPO:[Eu2+,Si4+],Mn2+ phosphor. The analysis of the luminescence properties indicates that the emission enhancement of Mn2+ in KBCPO:[Eu2+,Si4+],Mn2+ stems from the energy transfer of Eu2+ → Mn2+ with the mechanism of the electric dipole-dipole interaction when excited at 365 nm. In addition, KBCPO:[Eu2+,Si4+],Mn2+ also has excellent thermal stability and the emission color could be easily tuned from cyan to orange only by adjusting the Eu2+ doping level. These results confirm that the KBCPO:[Eu2+,Si4+],Mn2+ phosphor is a viable candidate for n-UV white light emitting diodes.

11.
RSC Adv ; 11(4): 2066-2073, 2021 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-35424188

RESUMEN

Glass ceramics (GCs) can perfectly integrate nanocrystals (NCs) into bulk materials. Herein, GCs containing LiYF4 NCs were fabricated via a traditional melt-quenching method and subsequent glass crystallization. Structural characterization was carried out via X-ray diffraction (XRD), transmission electron microscopy (TEM), selected area electron diffraction (SAED), and scanning transmission electron microscopy high-angle annular dark-field (STEM-HAADF) analysis, suggesting the precipitation of LiYF4 NCs from a glass matrix. Taking Eu3+ as a structural probe, the spectrographic features provide compelling evidence for the partition of dopants. In particular, intense upconversion (UC) emission was achieved when co-doped with Yb3+ and Er3+. Temperature-dependent UC emission behaviour was also established based on the fluorescence intensity ratio (FIR) of Er3+, to study its properties for optical thermometry. Furthermore, spectral conversion was attained through cross relaxation (CR) between Ce3+ and Ho3+, tuning from green to red with various Ce3+ doping concentrations. There is evidence that LiYF4 NC-embedded GCs were favorable for UC, which may be extremely promising for optical thermometry and spectral conversion applications. This work may open up new avenues for the exploration of GC materials for expansive applications.

12.
Dalton Trans ; 49(24): 8194-8200, 2020 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-32510534

RESUMEN

Eu3+ and Er3+ co-doped YNbO4 powder phosphors were synthesized by a traditional high-temperature solid-state reaction method. A laser of 487.6 nm wavelength was selected to be the excitation source which can pump Eu3+ ions from its thermally populated low-lying 7F2 ground state to the excited state 5D2 and lift the Er3+ ions from their 4I15/2 to 4F7/2 states. Fluorescence intensity ratio (FIR) between the 5D0 → 7FJ emissions of Eu3+ and 4S3/2 → 4I15/2 emissions of Er3+ ions is remarkably dependent on temperature because of the dramatic increase of Eu3+ luminescence against a slight quenching of Er3+ luminescence with the rise of temperature. This temperature sensitive FIR can be favorably employed for temperature sensing, owing to this novel scheme of 5D2 excitation, instead of 5D0, from 7F2 and utilizing Er3+ luminescence as a reference for FIR measurements. This sample is also prominent for its excellent signal-to-noise ratio and is a promising candidate for an optical temperature sensor.

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