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1.
Nature ; 626(8001): 984-989, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38326619

RESUMO

Controlled charge flows are fundamental to many areas of science and technology, serving as carriers of energy and information, as probes of material properties and dynamics1 and as a means of revealing2,3 or even inducing4,5 broken symmetries. Emerging methods for light-based current control5-16 offer particularly promising routes beyond the speed and adaptability limitations of conventional voltage-driven systems. However, optical generation and manipulation of currents at nanometre spatial scales remains a basic challenge and a crucial step towards scalable optoelectronic systems for microelectronics and information science. Here we introduce vectorial optoelectronic metasurfaces in which ultrafast light pulses induce local directional charge flows around symmetry-broken plasmonic nanostructures, with tunable responses and arbitrary patterning down to subdiffractive nanometre scales. Local symmetries and vectorial currents are revealed by polarization-dependent and wavelength-sensitive electrical readout and terahertz (THz) emission, whereas spatially tailored global currents are demonstrated in the direct generation of elusive broadband THz vector beams17. We show that, in graphene, a detailed interplay between electrodynamic, thermodynamic and hydrodynamic degrees of freedom gives rise to rapidly evolving nanoscale driving forces and charge flows under the extremely spatially and temporally localized excitation. These results set the stage for versatile patterning and optical control over nanoscale currents in materials diagnostics, THz spectroscopies, nanomagnetism and ultrafast information processing.

2.
Opt Express ; 32(11): 19361-19371, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38859072

RESUMO

A theoretical analysis is performed on the response of electrically pumped nano-laser arrays to external optical injection. The response to both continuous wave and modulated optical injection is explored. Continuous wave injection is shown to excite several varieties of dynamical behaviour in the array elements including regular dynamics and quasi-periodic behaviour. The strength of the optical injection, the frequency detuning between the injected light and the target laser, and the magnitude of the Purcell spontaneous emission enhancement factor are shown to markedly affect the dynamics. When subject to modulated optical injection, the effects of frequency detuning and optical injection strength are the focus of attention. It is shown that the elements of the array subject to modulated optical injection exhibit oscillatory behaviour over broad regimes determined by the optical injection strength and the frequency detuning.

3.
Opt Express ; 32(3): 4525-4536, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38297652

RESUMO

In this study, we present a simulation-based analysis of radio-over-fiber (ROF) transmission links incorporating both phase modulation (PM) and a single ring resonator (RR) as the modulation transformer (MT). This configuration offers cost-effectiveness, enhanced operational stability, facile reconfiguration, and heightened robustness. The optimization of the RR involves a comprehensive adjustment of the power coupler coupling coefficient (k) and the roundtrip optical phase shift (φ) to attain superior characteristics in terms of power output, bandwidth, dispersion, and nonlinearity, individually. The simulation encompasses the transmission of diverse data formats, including QPSK, 16QAM, and 16QAM-based OFDM, modulated by the PM-RR system. The results reveal a 0.25 dB improvement in nonlinearity tolerance, increased power, and superior fading mitigation compared to the conventional intensity modulation (IM) approach. Furthermore, through careful tuning of the phase response, the Q factor of the PM-RR system exhibits an enhancement exceeding 40% over a 100 km fiber length when compared to the Mach-Zehnder modulator (MZM) system.

4.
J Magn Reson Imaging ; 53(2): 516-526, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32841481

RESUMO

BACKGROUND: Acute myocardial infarction (AMI) is a disease with high morbidity and mortality worldwide and the evaluation of myocardial injury and perfusion status following myocardial ischemia and reperfusion is of clinical value. PURPOSE: To assess the diagnostic utility of simplified perfusion fraction (SPF) in differentiating salvage and infarcted myocardium and its predictive value for left ventricular remodeling in patients with reperfusion ST-segment elevation myocardial infarction (STEMI). STUDY TYPE: Prospective. POPULATION: Forty-one reperfused STEMI patients and 20 healthy volunteers. FIELD STRENGTH/SEQUENCE: 3.0T MRI. The MR examination included cine, T2 -short tau inversion recovery (T2 -STIR), first pass perfusiong (FPP),phase sensitive inversion recovery (PSIR), and diffusion-weighted imaging (DWI). ASSESSMENT: SPF values among different myocardium regions (infarcted, salvaged, remote, and MVO) and stages of reperfused STEMI patients as well as normal controls were measured. The diagnostic utility of SPF values in differentiating salvaged and infarcted myocardium was assessed. STATISTICAL ANALYSIS: Independent t-test and the Mann-Whitney U-test. Logistic regression. RESULTS: SPF values in healthy controls were not significantly different than SPF values in the remote myocardium of patients (40.09 ± 1.47% vs. 40.28 ± 1.93%, P = 0.698). In reperfusion STEMI patients, SPF values were lower in infarcted myocardium compared to remote and salvaged myocardium (32.15 ± 2.36% vs. 40.28 ± 1.93%, P < 0.001; 32.15 ± 2.36% vs. 36.68 ± 2.71%, P < 0.001). SPF values of infarcted myocardium showed a rebound increase from acute to convalescent stages (32.15 ± 2.36% vs. 34.69 ± 3.69%, P < 0.001). When differentiating infarcted and salvaged myocardium, SPF values demonstrated an area under the curve (AUC) of 0.89 (sensitivity 85.4%, specificity 80.5%, cutoff 34.42%). Lower SPF values were associated with lower odds ratio (OR = 0.304) of left ventricular remodeling after adjusting for potential confounders with a confidence interval (CI) of 0.129-0.717, P = 0.007. DATA CONCLUSION: SPF might be able to differentiate salvaged and infarcted myocardium and is a strong predictor of left ventricular remodeling in reperfused STEMI patients. Level of Evidence 2 Technical Efficacy Stage 2.


Assuntos
Infarto do Miocárdio , Infarto do Miocárdio com Supradesnível do Segmento ST , Humanos , Imagem Cinética por Ressonância Magnética , Infarto do Miocárdio/diagnóstico por imagem , Miocárdio , Perfusão , Valor Preditivo dos Testes , Estudos Prospectivos , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico por imagem , Função Ventricular Esquerda
5.
Nurs Health Sci ; 20(2): 165-172, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29235228

RESUMO

Nurses, like other healthcare professionals, such as physicians, pharmacists, and therapists, are susceptible to unanticipated patient harm, in which they suffer as second victims due to the immense personal and professional impact from the adverse event. The aim of the present study was to explore the psychological responses, coping strategies, and support needs of Singapore nurses as second victims of adverse events. A descriptive qualitative study was adopted. Eight participants (6 women and 2 men) who had been involved in an adverse event were interviewed and audio-recorded. Thematic analysis was performed to analyze the data. Seven themes emerged from the thematic analysis: responding psychologically after the event, feeling others' prejudice, having intrusive thoughts, drawing valuable lessons from the event, coping to recover after the event, taking responsibility for the mistakes made, and finding self-identity. The harmful effects of adverse events on nurses are long lasting. Second-victim nurses adopted various coping strategies to recover. The findings from the present study will guide the development of effective second-victim support programs.


Assuntos
Adaptação Psicológica , Enfermeiras e Enfermeiros/psicologia , Estresse Psicológico/etiologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pesquisa Qualitativa , Singapura , Apoio Social , Estresse Psicológico/psicologia , Local de Trabalho/psicologia , Local de Trabalho/normas
6.
Eur Radiol ; 27(11): 4710-4720, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28616727

RESUMO

OBJECTIVES: To evaluate the utility of diffusion kurtosis imaging (DKI) of patients with thyroid nodules and to assess the probable correlation with histopathological factors. METHODS: The study included 58 consecutive patients with thyroid nodules who underwent magnetic resonance imaging (MRI) examination, including DKI and diffusion-weighted imaging (DWI). Histopathological analysis of paraffin sections included cell density and immunohistochemical analysis of Ki-67 and vascular endothelial growth factor (VEGF). Statistical analyses were performed using Student's t-test, receiver operating characteristic (ROC) curves and Spearman's correlation. RESULTS: The diffusion parameters, cell density and immunohistochemistry analysis between malignant and benign lesions showed significant differences. The largest area under the ROC curve was acquired for the D value (AUC = 0.797). The highest sensitivity was shown with the use of K (threshold = 0.832, sensitivity = 0.917). The Ki-67 expression generally stayed low. A moderate correlation was found between ADC, D and cell density (r = -0.536, P = 0.000; r = -0.570, P = 0.000) and ADC, D and VEGF expression (r = -0.451, P = 0.000; r = -0.522, P = 0.000). CONCLUSION: The DKI-derived parameters D and K demonstrated an advantage compared to conventional DWI for thyroid lesion diagnosis. While the histopathological study indicated that the D value correlated better with extracellular change than the ADC value, the K value probably changed relative to the intracellular structure. KEY POINTS: • DWI and DKI parameters can identify PTC from benign thyroid nodules. • Correlations were found between diffusion parameters and histopathological analysis. • DKI obtains better diagnostic accuracy than conventional DWI.


Assuntos
Nódulo da Glândula Tireoide/diagnóstico por imagem , Adulto , Idoso , Carcinoma Papilar/diagnóstico por imagem , Carcinoma Papilar/patologia , Contagem de Células , Diagnóstico Diferencial , Imagem de Difusão por Ressonância Magnética/métodos , Imagem de Tensor de Difusão/métodos , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Curva ROC , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Nódulo da Glândula Tireoide/metabolismo , Nódulo da Glândula Tireoide/patologia , Fator A de Crescimento do Endotélio Vascular/metabolismo
7.
J Insect Sci ; 17(5)2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-29117371

RESUMO

MicroRNAs (miRNAs) are small endogenous noncoding single-stranded RNAs regulating gene expression in eukaryotes. They play important roles in regulating caste differentiation, behavior development, and immune defences in the honey bee, Apis mellifera (Linnaeus) (Hymenoptera: Apidae). In this study, we explored the effect of the neonicotinoid insecticide, thiamethoxam, on miRNA expression in this species using deep small RNA sequencing. The results showed that seven miRNAs were significantly differentially expressed (q-value <0.01 and |log2(fold-change)| >1) upon exposure to 10 ppb thiamethoxam over 10 d. Some candidate target genes were related to behavior, immunity, and neural function. Several miRNAs, including ame-miR-124, ame-miR-981, ame-miR-3791, and ame-miR-6038, were selected and further validated using real-time quantitative PCR analysis. The findings expand our understanding of the effects of neonicotinoid insecticides on honey bees at the molecular level.


Assuntos
Abelhas/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Inseticidas/toxicidade , MicroRNAs/metabolismo , Neonicotinoides/toxicidade , Nitrocompostos/toxicidade , Oxazinas/toxicidade , Tiazóis/toxicidade , Animais , Abelhas/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de RNA , Tiametoxam
8.
Nano Lett ; 16(2): 1392-7, 2016 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-26784952

RESUMO

We use temperature-dependent photoluminescence (PL), photoluminescence imaging, and time-resolved photoluminescence measurements to gain insights into the localization of excitons in single 2 nm GaAs/AlGaAs quantum well tube nanowires. PL spectra reveal the coexistence of localized and delocalized states at low temperatures, with narrow quantum dot-like emission lines on the high energy side of a broad emission band, and delocalized states on the low energy side. We find that the high energy QD-like emissions are metastable, disappearing at higher temperatures with only delocalized states (quantum well tube ground states) surviving. By comparing temperature- and time-dependent PL, we develop a theoretical model which provides insights into the confinement potentials and relaxation dynamics which localize the excitons in these quantum well tube nanowires.

9.
Hepatobiliary Pancreat Dis Int ; 15(4): 391-8, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27498579

RESUMO

BACKGROUND: Pyogenic hepatic abscess may mimic primary or secondary carcinoma of the liver on contrast-enhanced computed tomography (CECT). The present study was to explore the usefulness of the analysis of multislice-based texture acquired from CECT in the differentiation between pyogenic hepatic abscesses and malignant mimickers. METHODS: This retrospective study included 25 abscesses in 20 patients and 33 tumors in 26 subjects who underwent CECT. To make comparison, we also enrolled 19 patients with hepatic single simple cyst. The images from CECT were analyzed using a Laplacian of Gaussian band-pass filter (5 filter levels with sigma weighting ranging from 1.0 to 2.5). We also quantified the uniformity, entropy, kurtosis and skewness of the multislice-based texture at different sigma weightings. Statistical significance for these parameters was tested with one-way ANOVA followed by Tukey honestly significant difference (HSD) test. Diagnostic performance was evaluated using the receiver operating characteristic (ROC) curve analysis. RESULTS: There were significant differences in entropy and uniformity at all sigma weightings (P<0.001) among hepatic abscesses, malignant mimickers and simple cysts. The significant difference in kurtosis and skewness was shown at sigma 1.8 and 2.0 weightings (P=0.002-0.006). Tukey HSD test showed that the abscesses had a significantly higher entropy and lower uniformity compared with malignant mimickers (P=0.000-0.004). Entropy (at a sigma 2.0 weighting) had the largest area under the ROC curve (0.888) in differentiating abscesses from malignant mimickers, with a sensitivity of 81.8% and a specificity of 88.0% when the cutoff value was set to 3.64. CONCLUSION: Multislice-based texture analysis may be useful for differentiating pyogenic hepatic abscesses from malignant mimickers.


Assuntos
Meios de Contraste/administração & dosagem , Iohexol/análogos & derivados , Abscesso Hepático Piogênico/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico por imagem , Tomografia Computadorizada Multidetectores/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Diagnóstico Diferencial , Feminino , Humanos , Iohexol/administração & dosagem , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Valor Preditivo dos Testes , Curva ROC , Reprodutibilidade dos Testes , Estudos Retrospectivos
10.
Nano Lett ; 15(12): 7847-52, 2015 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-26562619

RESUMO

In this Letter, we explore the nature of exciton localization in single GaAs/AlGaAs nanowire quantum well tube (QWT) devices using photocurrent (PC) spectroscopy combined with simultaneous photoluminescence (PL) and photoluminescence excitation (PLE) measurements. Excitons confined to GaAs quantum well tubes of 8 and 4 nm widths embedded into an AlGaAs barrier are seen to ionize at high bias levels. Spectroscopic signatures of the ground and excited states confined to the QWT seen in PL, PLE, and PC data are consistent with simple numerical calculations. The demonstration of good electrical contact with the QWTs enables the study of Stark effect shifts in the sharp emission lines of excitons localized to quantum dot-like states within the QWT. Atomic resolution cross-sectional TEM measurements and an analysis of the quantum confined Stark effect of these dots provide insights into the nature of the exciton localization in these nanostructures.

11.
Nano Lett ; 15(3): 1876-82, 2015 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-25714336

RESUMO

We use low-temperature photoluminescence, photoluminescence excitation, and photoluminescence imaging spectroscopy to explore the optical and electronic properties of GaAs/AlGaAs quantum well tube (QWT) heterostructured nanowires (NWs). We find that GaAs QWTs with widths >5 nm have electronic states which are delocalized and continuous along the length of the NW. As the NW QWT width decreases from 5 to 1.5 nm, only a single electron state is bound to the well, and no optical excitations to a confined excited state are present. Simultaneously, narrow emission lines (fwhm < 600 µeV) appear which are localized to single spatial points along the length of the NW. We find that these quantum-dot-like states broaden at higher temperatures and quench at temperatures above 80 K. The lifetimes of these localized states are observed to vary from dot to dot from 160 to 400 ps. The presence of delocalized states and then localized states as the QWTs become more confined suggests both opportunities and challenges for possible incorporation into quantum-confined device structures.

12.
Nano Lett ; 13(3): 1016-22, 2013 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-23421755

RESUMO

The electronic properties of thin, nanometer scale GaAs quantum well tubes embedded inside the AlGaAs shell of a GaAs core-multishell nanowire are investigated using optical spectroscopies. Using numerical simulations to model cylindrically and hexagonally symmetric systems, we correlate these electronic properties with structural characterization by aberration-corrected scanning transmission electron microscopy of nanowire cross sections. These tubular quantum wells exhibit extremely high quantum efficiency and intense emission for extremely low submicrowatt excitation powers in both photoluminescence and photoluminescence excitation measurements. Numerical calculations of the confined eigenstates suggest that the electrons and holes in their ground states are confined to extremely localized one-dimensional filaments at the corners of the hexagonal structure which extend along the length of the nanowire.

13.
Nano Lett ; 13(11): 5367-72, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24134708

RESUMO

We use polarized photoluminescence excitation spectroscopy to observe the energy and symmetry of the predicted second conduction band in 130 nm diameter wurtzite InP nanowires. We find direct spectroscopic signatures for optical transitions among the A, B, and C hole bands and both the first and the second conduction bands. We determine that the splitting between the first and second conduction bands is 228 ± 7 meV in excellent agreement with theory. From these energies we show that the spin-orbit energy changes substantially between zinc blende and wurtzite InP. We discuss the two quite different solutions within the quasi-cubic approximation and the implications for these measurements. Finally, the observation of well-defined optical transitions between the B- and C-hole bands and the second conduction band suggests that either the theoretical description of the second conduction band as possessing Γ8 symmetry is incomplete, or other interactions are enabling these forbidden transitions.


Assuntos
Índio/química , Nanofios/química , Órbita , Fosfinas/química , Zinco/química , Luz , Tamanho da Partícula , Análise Espectral , Propriedades de Superfície
14.
Geriatr Gerontol Int ; 24 Suppl 1: 182-188, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38095277

RESUMO

AIM: SARC-F is limited by low sensitivity for sarcopenia identification. As surrogates of muscle mass, mid-arm circumference (MAC) and/or calf circumference have been proposed as additions to SARC-F to enhance sarcopenia identification. The aim of this study was to evaluate the diagnostic performance of SARC-F, SARC-CalF, SARC-F + MAC, and SARC-CalF + MAC in sarcopenia detection, and to assess the impact of obesity on their diagnostic performance. METHODS: We studied 230 healthy non-frail community-dwelling older adults age >50 years. We performed receiver operating characteristic curve analysis for SARC-F, SARC-CalF, SARC-F + MAC and SARC-CalF + MAC against sarcopenia diagnosed by the Asian Working Group for Sarcopenia (AWGS) 2019 as the reference standard. Obesity was defined by high waist circumference (men ≥90 cm, women ≥80 cm). We performed subgroup analysis to compare between obese and non-obese groups. RESULTS: The prevalence of sarcopenia was 27.0% by AWGS 2019. SARC-CalF + MAC had the best diagnostic performance (area under the curve [AUC] 0.74, 95% confidence interval [CI] 0.67-0.81; sensitivity 66.1%; specificity 69.1%), followed by SARC-CalF (AUC 0.70, 95% CI 0.62-0.78; sensitivity 21.0%; specificity 95.8%). SARC-F (AUC 0.57, 95% CI 0.49-0.66; sensitivity 0%; specificity 100%) performed significantly worsethan its modified versions (P < 0.05). There was higher accuracy of sarcopenia identification in obese compared with non-obese groups for SARC-F + MAC (AUC 0.75, 95% CI 0.65-0.85 vs. 0.58, 95% CI 0.46-0.70) and SARC-CalF + MAC (AUC 0.75, 95% CI 0.66-0.85 vs. 0.70, 95% CI 0.59-0.81). CONCLUSIONS: The addition of arm circumference to SARC-CalF confers better diagnostic accuracy for sarcopenia identification, especially in the obese group. Thus, MAC may complement SARC-CalF for community screening of sarcopenia amongst healthy community-dwelling older adults by increasing sensitivity for the detection of sarcopenic obesity. Geriatr Gerontol Int 2024; 24: 182-188.


Assuntos
Sarcopenia , Masculino , Humanos , Feminino , Idoso , Sarcopenia/diagnóstico , Sarcopenia/epidemiologia , Programas de Rastreamento , Curva ROC , Perna (Membro) , Avaliação Geriátrica , Obesidade/complicações , Obesidade/diagnóstico , Obesidade/epidemiologia , Inquéritos e Questionários
15.
Front Cardiovasc Med ; 10: 1115290, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37144057

RESUMO

Background: Total aortic root replacement (TRR) is certainly beneficial for aortic root disease, but does it still have an advantageous prognosis for patients compared to valve-sparing aortic root replacement (VSRR)? An overview of reviews was conducted to assess each of their clinical efficacy/effectiveness. Review methods: Systematic reviews (SRs)/Meta-analyses comparing the prognosis of TRR and VSRR in aortic root surgery were collected from 4 databases, all searched from the time of database creation to October 2022. Two evaluators independently screened the literature, extracted information and applied the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement, A Measurement Tool to Assess Systematic Reviews 2 (AMSTAR 2) tool, Grading of Recommendations, Assessment, Development and Evaluations (GRADE), and Risk of Bias in Systematic Reviews (ROBIS) to evaluate the quality of reporting, methodological quality, risk of bias, and level of evidence of the included studies. Main results: A total of 9 SRs/Meta-analyses were ultimately included. In terms of the reporting quality of the included studies, PRISMA scores ranged from 14 to 22.5, with issues mainly in reporting bias assessment, risk of study bias, credibility of evidence, protocol and registration, and funding sources. The methodological quality of the included SRs/Meta-analyses was generally low, with key items 2, 7, and 13 having major flaws and non-key items 10, 12, and 16. In terms of risk of bias assessment, the overall assessment of the included 9 studies was high-risk. The quality of the evidence was rated as low to very low quality for the three outcome indicators selected for the GRADE quality of evidence rating: early (within 30 days postoperatively or during hospitalization) mortality, late mortality, and valve reintervention rate. Conclusions: VSRR has many benefits including reduced early and late mortality after aortic root surgery and reduced rates of valve-related adverse events, but the methodological quality of the relevant studies is low, and there is a lack of high-quality evidence to support this. Systematic Review Registration: https://www.PROSPERO, identifier: CRD42022381330.

16.
ACS Appl Mater Interfaces ; 15(9): 12560-12569, 2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36847242

RESUMO

Tunable terahertz (THz) photonic devices are imperative in a wide range of applications ranging from THz signal modulation to molecular sensing. One of the currently prevailing methods is based on arrays of metallic or dielectric resonators integrated with functional materials in response to an external stimulus, in which for the purpose of sensing the external stimuli may introduce inadvertent undesirable effects into the target samples to be measured. Here we developed an alternative approach by postprocessing nanothickness macro-assembled graphene (nMAG) films with widely tunable THz conductivity, enabling versatile solid-state THz devices and sensors, showing multifunctional nMAG-based applications. The THz conductivities of free-standing nMAGs showed a broad range from 1.2 × 103 S/m in reduced graphene oxide before annealing to 4.0 × 106 S/m in a nMAG film annealed at 2800 °C. We fabricated nMAG/dielectric/metal and nMAG/dielectric/nMAG THz Salisbury absorbers with broad reflectance ranging from 0% to 80%. The highly conductive nMAG films enabled THz metasurfaces for sensing applications. Taking advantage of the resonant field enhancement arising from the plasmonic metasurface structures and the strong interactions between analyte molecules and nMAG films, we successfully detected diphenylamine with a limit of detection of 4.2 pg. Those wafer-scale nMAG films present promising potential in high-performance THz electronics, photonics, and sensors.

17.
Environ Int ; 164: 107257, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35486965

RESUMO

Tire wear microplastic particles (TWMPs) are emerging microplastic pollutants that have gained increasing attention lately. However, the health effect of inhaled airborne TWMPs has never been explored before and may already be included in particulate matter morbidity and mortality. Here, we endeavored to address the preliminary study of TWMP inhalation-induced pulmonary toxic effects and its epigenetic mechanisms in C57BL/6 mice. As a result, restricted ventilatory dysfunction and fibrotic pathological changes were observed in TWMP-treaded mice. Further research found that attenuation of miR-1a-3p plays an important role in TWMP-induced lung injury. Results from in vitro study confirmed that cytoskeleton regulatory gene twinfilin-1 was one of the target genes of miR-1a-3p, and involved in cytoskeleton rearrangement caused by TWMP exposure. Mechanistically, miR-1a-3p inhibited the F-actin formation by targeting cytoskeletal regulatory proteins twinfilin-1, leading to TWMP-induced pulmonary fibrotic injury. While we are in the very early stages of explaining the role of epigenetics in TWMP-induced lung injury, the potential for the use of epigenetic marks as biomarkers is high and discoveries made in this field will likely bring us closer to better understanding this crucial mechanism.


Assuntos
Lesão Pulmonar , MicroRNAs , Animais , Citoesqueleto/metabolismo , Lesão Pulmonar/induzido quimicamente , Lesão Pulmonar/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Microplásticos , Plásticos/metabolismo
18.
Environ Pollut ; 305: 119293, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35421554

RESUMO

As a widely used pure elemental carbon in colloidal particles, carbon black was listed as a group 2B carcinogen by IARC in 2010. The most available mechanism information about carbon black and carcinogenesis are from in vivo or in vitro studies. However, few studies concerned the nanoparticle's real-ambient exposure causing systemic change and further affecting the target organ. Herein, we used an ex vivo biosensor assay to investigate the transcriptome change of primary bronchial epithelial cells after treatment with the plasma from workers with long-term occupational carbon black exposure history. Based on ex vivo biosensor assay and transcriptome sequencing, we found the effect of internal systemic environment on epithelial cells after carbon black exposure was an inflammatory response, which mainly activates cell cycle-related pathways. After exposure to carbon black, the internal systemic environment could activate cancer-related pathways like epithelial-mesenchymal transition, hypoxia, TNF-α signaling via NF-κB. The hub genes in the carbon black group (CDC20 and PLK1) and their correlation with the systemic environment were uncovered by constructing the protein-protein interaction network. Inflammatory cytokines, especially CRP, were strongly correlated with the expression of CDC20 and PLK1. Besides, we also find a strong correlation between CDC20 and cytokinesis-block micronucleus endpoints in peripheral blood (rho = 0.591, P < 0.001). Our results show that long-term carbon black exposure might activate cell cycle-related pathways through circulating inflammation and increase the risk of cancer, while the oxidative stress caused by diesel exhaust particles are mainly related to PAHs exposure. After exposure to carbon black, the systemic environment could activate cancer-related pathways like diesel exhaust particles, increasing the risk of lung cancer. These attempts might provide a further understanding of the indirect effect of chronic occupational inhaled carbon black exposure on pulmonary carcinogenesis.


Assuntos
Neoplasias Pulmonares , Nanopartículas , Carbono , Carcinogênese , Divisão Celular , Humanos , Inflamação/induzido quimicamente , Nanopartículas/toxicidade , Fuligem/toxicidade , Emissões de Veículos
19.
Front Pharmacol ; 13: 960140, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36304153

RESUMO

In recent years, small intestine as a key target in the treatment of Inflammatory bowel disease caused by NSAIDs has become a hot topic. Sanguinarine (SA) is one of the main alkaloids in the Macleaya cordata extracts with strong pharmacological activity of anti-tumor, anti-inflammation and anti-oxidant. SA is reported to inhibit acetic acid-induced colitis, but it is unknown whether SA can relieve NSAIDs-induced small intestinal inflammation. Herein, we report that SA effectively reversed the inflammatory lesions induced by indomethacin (Indo) in rat small intestine and IEC-6 cells in culture. Our results showed that SA significantly relieved the symptoms and reversed the inflammatory lesions of Indo as shown in alleviation of inflammation and improvement of colon macroscopic damage index (CMDI) and tissue damage index (TDI) scores. SA decreased the levels of TNF-α, IL-6, IL-1ß, MDA and LDH in small intestinal tissues and IEC-6 cells, but increased SOD activity and ZO-1 expression. Mechanistically, SA dose-dependently promoted the expression of Nrf2 and HO-1 by decreasing Keap-1 level, but inhibited p65 phosphorylation and nuclear translocation in Indo-treated rat small intestine and IEC-6 cells. Furthermore, in SA treated cells, the colocalization between p-p65 and CBP in the nucleus was decreased, while the colocalization between Nrf2 and CBP was increased, leading to the movement of gene expression in the nucleus to the direction of anti-inflammation and anti-oxidation. Nrf2 silencing blocked the effects of SA. Together our results suggest that SA can significantly prevent intestinal inflammatory lesions induced by Indo in rats and IEC-6 cells through regulation of the Nrf2 pathway and NF-κBp65 pathway.

20.
Front Physiol ; 12: 663040, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34093226

RESUMO

The olfactory system is used by insects to find hosts, mates, and oviposition sites. Insects have different types of olfactory proteins, including odorant-binding proteins (OBPs), chemosensory proteins (CSPs), odorant receptors (ORs), ionotropic receptors (IRs), and sensory neuron membrane proteins (SNMPs) to perceive chemical cues from the environment. The greater wax moth, Galleria mellonella, is an important lepidopteran pest of apiculture. However, the molecular mechanism underlying odorant perception in this species is unclear. In this study, we performed transcriptome sequencing of G. mellonella antennae to identify genes involved in olfaction. A total of 42,544 unigenes were obtained by assembling the transcriptome. Functional classification of these unigenes was determined by searching against the Gene Ontology (GO), eukaryotic orthologous groups (KOG), and the Kyoto Encyclopedia of Genes and Genomes (KEGG) databases. We identified a total of 102 olfactory-related genes: 21 OBPs, 18 CSPs, 43 ORs, 18 IRs, and 2 SNMPs. Results from BLASTX best hit and phylogenetic analyses showed that most of the genes had a close relationship with orthologs from other Lepidoptera species. A large number of OBPs and CSPs were tandemly arrayed in the genomic scaffolds and formed gene clusters. Reverse transcription-quantitative PCR results showed that GmelOBP19 and GmelOR47 are mainly expressed in male antennae. This work provides a transcriptome resource for olfactory genes in G. mellonella, and the findings pave the way for studying the function of these genes.

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