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1.
Respir Res ; 21(1): 72, 2020 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-32197620

RESUMO

BACKGROUND: Although phosphodiesterase-4 (PDE4) inhibitors have been shown to reduce COPD exacerbation rate, their biological mechanism of action is not completely elucidated at the molecular level. We aimed to characterise the whole genome gene expression profile of the inhaled PDE4-inhibitor CHF6001 on top of triple therapy in sputum cells and whole blood of patients with COPD and chronic bronchitis. METHODS: Whole genome gene expression analysis was carried out by microarray in 54 patients before and after 32 days treatment with CHF6001 800 and 1600 µg and placebo twice daily (BID) in a randomised crossover study. RESULTS: CHF6001 had a strong effect in sputum, with 1471 and 2598 significantly differentially-expressed probe-sets relative to placebo (p-adjusted for False Discovery Rate < 0.05) with 800 and 1600 µg BID, respectively. Functional enrichment analysis showed significant modulation of key inflammatory pathways involved in cytokine activity, pathogen-associated-pattern-recognition activity, oxidative stress and vitamin D with associated inhibition of downstream inflammatory effectors. A large number of pro-inflammatory genes coding for cytokines and matrix-metalloproteinases were significantly differentially expressed for both doses; the majority (> 87%) were downregulated, including macrophage inflammatory protein-1-alpha and 1-beta, interleukin-27-beta, interleukin-12-beta, interleukin-32, tumour necrosis factor-alpha-induced-protein-8, ligand-superfamily-member-15, and matrix-metalloproteinases-7,12 and 14. The effect in blood was not significant. CONCLUSIONS: Inhaled PDE4 inhibition by CHF6001 on top of triple therapy in patients with COPD and chronic bronchitis significantly modulated key inflammatory targets and pathways in the lung but not in blood. Mechanistically these findings support a targeted effect in the lung while minimising unwanted systemic class-effects. TRIAL REGISTRATION: ClinicalTrial.gov, EudraCT, 2015-005550-35. Registered 15 July 2016.


Assuntos
Bronquite Crônica/tratamento farmacológico , Inibidores da Fosfodiesterase 4/administração & dosagem , Escarro/citologia , Administração por Inalação , Idoso , Anti-Inflamatórios/administração & dosagem , Biomarcadores/sangue , Biomarcadores/metabolismo , Bronquite Crônica/metabolismo , Estudos Cross-Over , Feminino , Humanos , Mediadores da Inflamação , Masculino , Inibidores da Fosfodiesterase 4/uso terapêutico , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Doença Pulmonar Obstrutiva Crônica/metabolismo , Escarro/metabolismo , Sulfonamidas , Transcriptoma , para-Aminobenzoatos
2.
Nano Lett ; 19(3): 1613-1617, 2019 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-30786717

RESUMO

We propose a design concept for tailoring the local density of optical states (LDOS) in dielectric nanostructures, based on the phase distribution of the scattered optical fields induced by point-like emitters. First we demonstrate that the LDOS can be expressed in terms of a coherent summation of constructive and destructive contributions. By using an iterative approach, dielectric nanostructures can be designed to effectively remove the destructive terms. In this way, dielectric Mie resonators, featuring low LDOS for electric dipoles, can be reshaped to enable enhancements of 3 orders of magnitude. To demonstrate the generality of the method, we also design nanocavities that enhance the radiated power of a circular dipole, a quadrupole, and an arbitrary collection of coherent dipoles. Our concept provides a powerful tool for high-performance dielectric resonators and affords fundamental insights into light-matter coupling at the nanoscale.

3.
Lancet ; 391(10125): 1076-1084, 2018 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-29429593

RESUMO

BACKGROUND: Evidence is scarce on the relative risk-benefit of inhaled triple therapy, consisting of inhaled corticosteroid, long-acting muscarinic antagonist, and long-acting ß2-agonist, versus dual bronchodilation for chronic obstructive pulmonary disease (COPD). We aimed to compare a single-inhaler triple combination of beclometasone dipropionate, formoterol fumarate, and glycopyrronium (BDP/FF/G) versus a single-inhaler dual bronchodilator combination of indacaterol plus glycopyrronium (IND/GLY) in terms of the rate of moderate-to-severe COPD exacerbations over 52 weeks of treatment. METHODS: This randomised, parallel-group, double-blind, double-dummy study was done at 187 sites across 17 countries. Eligible patients had symptomatic COPD, severe or very severe airflow limitation, at least one moderate or severe exacerbation in the previous year, and were receiving inhaled maintenance medication. After a 2 week run-in period with one inhalation per day of IND/GLY (85 µg/43 µg), patients were randomly assigned (1:1), via an interactive response technology system, to receive 52 weeks of treatment with two inhalations of extrafine BDP/FF/G (87 µg/5 µg/9 µg) twice per day or one inhalation of IND/GLY (85 µg/43 µg) per day. Randomisation was stratified by country and severity of airflow limitation. The primary endpoint was the rate of moderate-to-severe COPD exacerbations across 52 weeks of treatment in all randomised patients who received at least one dose of study drug and had at least one post-baseline efficacy assessment. Safety was assessed in all patients who received at least one dose of study drug. This study is registered with ClinicalTrials.gov, number NCT02579850. FINDINGS: Between May, 29 2015, and July 10, 2017, 1532 patients received BDP/FF/G (n=764) or IND/GLY (n=768). Moderate-to-severe exacerbation rates were 0·50 per patient per year (95% CI 0·45-0·57) for BDP/FF/G and 0·59 per patient per year (0·53-0·67) for IND/GLY, giving a rate ratio of 0·848 (0·723-0·995, p=0·043) in favour of BDP/FF/G. Adverse events were reported by 490 (64%) of 764 patients receiving BDP/FF/G and 516 (67%) of 768 patients receiving IND/GLY. Pneumonia occurred in 28 (4%) patients receiving BDP/FF/G versus 27 (4%) patients receiving IND/GLY. One treatment-related serious adverse event occurred in each group: dysuria in a patient receiving BDP/FF/G and atrial fibrillation in a patient receiving IND/GLY. INTERPRETATION: In patients with symptomatic COPD, severe or very severe airflow limitation, and an exacerbation history despite maintenance therapy, extrafine BDP/FF/G significantly reduced the rate of moderate-to-severe exacerbations compared with IND/GLY, without increasing the risk of pneumonia. FUNDING: Chiesi Farmaceutici.


Assuntos
Agonistas de Receptores Adrenérgicos beta 2/administração & dosagem , Beclometasona/administração & dosagem , Fumarato de Formoterol/administração & dosagem , Glucocorticoides/administração & dosagem , Glicopirrolato/administração & dosagem , Antagonistas Muscarínicos/administração & dosagem , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Administração por Inalação , Idoso , Broncodilatadores/administração & dosagem , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Humanos , Indanos/administração & dosagem , Masculino , Pessoa de Meia-Idade , Quinolonas/administração & dosagem
4.
Lancet ; 389(10082): 1919-1929, 2017 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-28385353

RESUMO

BACKGROUND: Limited data are available for the efficacy of triple therapy with two long-acting bronchodilators and an inhaled corticosteroid in chronic obstructive pulmonary disease (COPD). We compared treatment with extrafine beclometasone dipropionate, formoterol fumarate, and glycopyrronium bromide (BDP/FF/GB; fixed triple) with tiotropium, and BDP/FF plus tiotropium (open triple). METHODS: For this double-blind, parallel-group, randomised, controlled trial, eligible patients had COPD, post-bronchodilator forced expiratory volume in 1 s (FEV1) of less than 50%, at least one moderate-to-severe COPD exacerbation in the previous 12 months, and a COPD Assessment Test total score of at least 10. After a 2-week run-in period receiving one inhalation per day via single-dose dry-powder inhaler of open-label 18 µg tiotropium, patients were randomised (2:2:1) using a interactive response technology system to 52 weeks treatment with tiotropium, fixed triple, or open triple. Randomisation was stratified by country and severity of airflow limitation. The primary endpoint was moderate-to-severe COPD exacerbation rate. The key secondary endpoint was change from baseline in pre-dose FEV1 at week 52. The trial is registered with ClinicalTrials.gov, number NCT01911364. FINDINGS: Between Jan 21, 2014, and March 18, 2016, 2691 patients received fixed triple (n=1078), tiotropium (n=1075), or open triple (n=538). Moderate-to-severe exacerbation rates were 0·46 (95% CI 0·41-0·51) for fixed triple, 0·57 (0·52-0·63) for tiotropium, and 0·45 (0·39-0·52) for open triple; fixed triple was superior to tiotropium (rate ratio 0·80 [95% CI 0·69-0·92]; p=0·0025). For week 52 pre-dose FEV1, fixed triple was superior to tiotropium (mean difference 0·061 L [0·037 to 0·086]; p<0·0001) and non-inferior to open triple (-0·003L [-0·033 to 0·027]; p=0·85). Adverse events were reported by 594 (55%) patients with fixed triple, 622 (58%) with tiotropium, and 309 (58%) with open triple. INTERPRETATION: In our TRINITY study, treatment with extrafine fixed triple therapy had clinical benefits compared with tiotropium in patients with symptomatic COPD, FEV1 of less than 50%, and a history of exacerbations. FUNDING: Chiesi Farmaceutici SpA.


Assuntos
Beclometasona/administração & dosagem , Broncodilatadores/administração & dosagem , Fumarato de Formoterol/administração & dosagem , Glucocorticoides/administração & dosagem , Glicopirrolato/administração & dosagem , Antagonistas Muscarínicos/administração & dosagem , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Brometo de Tiotrópio/administração & dosagem , Administração por Inalação , Adulto , Idoso , Método Duplo-Cego , Feminino , Volume Expiratório Forçado , Humanos , Masculino , Pessoa de Meia-Idade , Nebulizadores e Vaporizadores
5.
Phys Rev Lett ; 120(4): 043902, 2018 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-29437435

RESUMO

Materials with a spatially uniform but temporally varying optical response have applications ranging from magnetic field-free optical isolators to fundamental studies of quantum field theories. However, these effects typically become relevant only for time variations oscillating at optical frequencies, thus presenting a significant hurdle that severely limits the realization of such conditions. Here we present a thin-film material with a permittivity that pulsates (uniformly in space) at optical frequencies and realizes a time-reversing medium of the form originally proposed by Pendry [Science 322, 71 (2008)SCIEAS0036-807510.1126/science.1162087]. We use an optically pumped, 500 nm thick film of epsilon-near-zero (ENZ) material based on Al-doped zinc oxide. An incident probe beam is both negatively refracted and time reversed through a reflected phase-conjugated beam. As a result of the high nonlinearity and the refractive index that is close to zero, the ENZ film leads to time reversed beams (simultaneous negative refraction and phase conjugation) with near-unit efficiency and greater-than-unit internal conversion efficiency. The ENZ platform therefore presents the time-reversal features required, e.g., for efficient subwavelength imaging, all-optical isolators and fundamental quantum field theory studies.

6.
Lancet ; 388(10048): 963-73, 2016 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-27598678

RESUMO

BACKGROUND: Few data are available for the efficacy of "triple therapy" with two long-acting bronchodilators and an inhaled corticosteroid in chronic obstructive pulmonary disease (COPD). We designed this study to assess efficacy of single-inhaler combination of an extra fine formulation of beclometasone dipropionate, formoterol fumarate, and glycopyrronium bromide (BDP/FF/GB) in COPD compared with beclometasone dipropionate and formoterol fumarate (BDP/FF) treatment. METHODS: TRILOGY was a randomised, parallel group, double-blind, active-controlled study done in 159 sites across 14 countries. The sites were a mixture of primary, secondary, and tertiary care providers, and specialist investigation units. Eligible patients with COPD had post-bronchodilator forced expiratory volume in 1 s (FEV1) of lower than 50%, one or more moderate-to-severe COPD exacerbation in the previous 12 months, COPD Assessment Test total score of 10 or more, and a Baseline Dyspnea Index focal score of 10 or less. Patients who met the inclusion and exclusion criteria at screening entered a 2-week open-label run-in period where they received beclometasone dipropionate (100 µg) and formoterol fumarate (6 µg) in two actuations twice daily. Patients were then randomly assigned (1:1) with an interactive response technology system to either continue BDP (100 µg) and FF (6 µg) or step-up to BDP (100 µg), FF (6 µg), and GB (12·5 µg) in two actuations twice daily for 52 weeks via pressurised metered-dose inhaler. The three co-primary endpoints were pre-dose FEV1, 2-h post-dose FEV1, and Transition Dyspnea Index (TDI) focal score, all measured at week 26 in the intention-to-treat population (all patients who were randomly assigned and received at least one dose of study drug and had at least one post-baseline efficacy assessment). Safety outcomes were measured in the safety population (all patients who were randomly assigned and received at least one dose of study drug). Secondary endpoints included moderate-to-severe COPD exacerbation rate over 52 weeks. This study is registered with ClinicalTrials.gov number NCT01917331. FINDINGS: Between March 21, 2014, and Jan 14, 2016, 1368 patients received either BDP/FF/GB (n=687) or BDP/FF (n=681). At week 26, BDP/FF/GB improved pre-dose FEV1 by 0·081 L (95% CI 0·052-0·109; p<0·001) and 2-h post-dose FEV1 by 0·117 L (0·086-0·147; p<0·001) compared with BDP/FF. Mean TDI focal scores at week 26 were 1·71 for BDP/FF/GB and 1·50 for BDP/FF, with a difference of 0·21 (95% CI -0·08 to 0·51; p=0·160). Adjusted annual moderate-to-severe exacerbation frequencies were 0·41 for BDP/FF/GB and 0·53 for BDP/FF (rate ratio 0·77 [95% CI 0·65-0·92]; p=0·005), corresponding to a 23% reduction in exacerbations with BDP/FF/GB compared with BDP/FF. Adverse events were reported by 368 (54%) patients with BDP/FF/GB and 379 (56%) with BDP/FF. One serious treatment-related adverse event occurred (atrial fibrillation) in a patient in the BDP/FF/GB group. INTERPRETATION: We provide evidence for the clinical benefits of stepping up patients with COPD from an inhaled corticosteroid/long-acting ß2-agonist combination treatment to triple therapy using a single inhaler. FUNDING: Chiesi Farmaceutici SpA.


Assuntos
Corticosteroides/administração & dosagem , Agonistas de Receptores Adrenérgicos beta 2/administração & dosagem , Antagonistas Muscarínicos/administração & dosagem , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Administração por Inalação , Idoso , Preparações de Ação Retardada , Método Duplo-Cego , Combinação de Medicamentos , Quimioterapia Combinada , Dispneia/induzido quimicamente , Feminino , Volume Expiratório Forçado/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Nebulizadores e Vaporizadores , Resultado do Tratamento
7.
Phys Chem Chem Phys ; 18(45): 31107-31114, 2016 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-27812574

RESUMO

Multiple exciton generation (MEG) is a promising process to improve the power conversion efficiency of solar cells. PbSe quantum dots (QDs) have shown reasonably high MEG quantum yield (QY), although the photon energy threshold for this process is still under debate. One of the reasons for this inconsistency is the complicated competition of MEG and hot exciton cooling, especially at higher excited states. Here, we investigate MEG QY and the origin of the photon energy threshold for MEG in PbSe QDs of three different sizes by studying the transient absorption (TA) spectra, both at the band gap (near infrared, NIR) and far from the band gap energy (visible range). The comparison of visible TA spectra and dynamics for different pump wavelengths, below, around and above the MEG threshold, provides evidence of the role of the Σ transition in slowing down the exciton cooling process that can help MEG to take over the phonon relaxation process. The universality of this behavior is confirmed by studying QDs of three different sizes. Moreover, our results suggest that MEG QY can be determined by pump-probe experiments probed above the band gap.

8.
Pulm Pharmacol Ther ; 30: 121-7, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25088067

RESUMO

BACKGROUND: The fixed combination of extrafine beclomethasone dipropionate and formoterol fumarate (BDP/FF) pMDI (Foster(®)) is approved for treatment of adult asthmatic patients. In order to provide an alternative drug delivery system for BDP/FF to physicians and patients, a dry powder inhaler (NEXThaler(®)) has been developed, capable to deliver extrafine particles to the lungs and therefore improve the dosing of the drugs, especially in patients with poor hand-breath coordination. OBJECTIVE: This trial was performed to compare efficacy and safety of extrafine BDP/FF NEXThaler(®) with extrafine BDP/FF pMDI or non-extrafine BDP DPI alone in adult patients with controlled asthma. METHODS: In this 8-week randomised, double-blind, parallel-group trial, patients were randomized to receive either extrafine BDP/FF NEXThaler(®) 100/6 µg bid, extrafine BDP/FF 100/6 µg pMDI bid or non-extrafine BDP DPI 100 µg bid. The primary efficacy variable was change from baseline to the entire 8-week randomised treatment period in average pre-dose morning PEF. RESULTS: The ITT population comprised 754 patients. Extrafine BDP/FF NEXThaler(®) was non-inferior (pre-defined margin: -15 L/min) relative to extrafine BDP/FF pMDI (mean difference: -1.84; 95% CI: -6.73, 3.05) in terms of the primary efficacy variable, change from baseline in average pre-dose morning PEF. Statistical superiority of both extrafine BDP/FF formulations over non-extrafine BDP DPI was demonstrated for the primary efficacy variable (providing evidence of assays sensitivity of the trial), ACQ score and percentage of rescue medication use-free days. No significant safety signals were observed. CONCLUSION: NEXThaler(®) is an effective and well-tolerated delivery device for treatment of patients with asthma who need a regular treatment.


Assuntos
Antiasmáticos/uso terapêutico , Asma/tratamento farmacológico , Beclometasona/uso terapêutico , Etanolaminas/uso terapêutico , Administração por Inalação , Adolescente , Adulto , Idoso , Antiasmáticos/administração & dosagem , Antiasmáticos/efeitos adversos , Beclometasona/administração & dosagem , Beclometasona/efeitos adversos , Método Duplo-Cego , Inaladores de Pó Seco , Etanolaminas/administração & dosagem , Etanolaminas/efeitos adversos , Feminino , Fumarato de Formoterol , Humanos , Masculino , Inaladores Dosimetrados , Pessoa de Meia-Idade , Tamanho da Partícula , Resultado do Tratamento , Adulto Jovem
11.
Nat Commun ; 15(1): 7752, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39237541

RESUMO

Time-varying metamaterials rely on large and fast changes of the linear permittivity. Beyond the linear terms, however, the effect of a non-perturbative modulation of the medium on harmonic generation remains largely unexplored. In this work, we study second harmonic generation at an optically pumped time-varying interface between air and a 310 nm Indium Tin Oxide film. We observe a modulation contrast at the second harmonic wavelength up to 93% for a pump intensity of 100 GW/cm2, leading to large frequency broadening and shift. We experimentally demonstrate that a significant contribution to the enhancement comes from the temporal modulation of the second order nonlinear susceptibility. Moreover, we show the frequency-modulated spectra resulting from single and double-slit time diffraction could be exploited for enhanced optical computing and sensing, enabling broadband time-varying effects on the harmonic signal and extending the application of Epsilon-Near-Zero materials to the visible range.

13.
Nanoscale ; 15(4): 1645-1651, 2023 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-36597874

RESUMO

Giant shell CdSe/CdS quantum dots are bright and flexible emitters, with near-unity quantum yield and suppressed blinking, but their single photon purity is reduced by efficient multiexcitonic emission. We report the observation, at the single dot level, of a large blueshift of the photoluminescence biexciton spectrum (24 ± 5 nm over a sample of 32 dots) for pure-phase wurtzite quantum dots. By spectral filtering, we demonstrate a 2.3 times reduction of the biexciton quantum yield relative to the exciton emission, while preserving as much as 60% of the exciton single photon emission, thus improving the purity from g2(0) = 0.07 ± 0.01 to g2(0) = 0.03 ± 0.01. At a larger pump fluency, spectral purification is even more effective with up to a 6.6 times reduction in g2(0), which is due to the suppression of higher order excitons and shell states experiencing even larger blueshifts. Our results indicate the potential for the synthesis of engineered giant shell quantum dots, with further increased biexciton blueshifts, for quantum optical applications requiring both high purity and brightness.

14.
Liver Transpl ; 16(4): 503-12, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20373461

RESUMO

Transplantation is the treatment of choice for hepatocellular carcinoma (HCC) meeting the Milan criteria. HCC and chronic liver diseases have distinct natural histories for which an equitable transplant policy must account. We enrolled and prospectively followed at a single center 206 consecutive HCC patients that presented within the Milan criteria. Patients were treated per the Barcelona Clinic Liver Cancer (BCLC) algorithm; 95% received resection, ablation, or transarterial chemoembolization. The median follow-up was 16 months. Progression occurred in 84 patients, and 8 patients died. Risk factors for the time to disease progression (death or progression beyond T2) were analyzed in 170 patients with a complete data set. Risk factors with the strongest relationship to progression included tumor diameter and tumor persistence/recurrence after local therapy (hazard ratios of 1.51 and 2.75, respectively, when transplanted patients were censored at the time of transplantation and hazard ratios of 1.53 and 3.66, respectively, when transplantation was counted as an event; P < or = 0.0001). To evaluate the current Model for End-Stage Liver Disease (MELD) exception, we compared the expected progression rate (PR) with our observed PR in 133 stage T2 patients. The current policy resulted in a large overestimation of the PR for T2 HCC and an unsatisfactory performance [Harrell's concordance index (C index) = 0.60, transplant censored; C index = 0.55, transplant as progression]. Risk factors for progression that were identified by univariate analysis were considered for multivariate analysis. With these risk factors and the patients' natural MELD scores, an adjusted model applicable to organ allocation was generated, and this decreased the discrepancy between the expected and observed PRs (C index = 0.66, transplant censored; C index = 0.69, transplant as progression). In conclusion, the current MELD exception largely overestimates progression in T2 patients treated according to the BCLC guidelines. The tumor response to resective or ablative treatment can predict tumor progression beyond the Milan criteria, and it should be taken into account in models designed to prioritize organ allocation.


Assuntos
Carcinoma Hepatocelular/terapia , Hepatopatias/diagnóstico , Neoplasias Hepáticas/terapia , Transplante de Fígado/métodos , Idoso , Algoritmos , Estudos de Coortes , Progressão da Doença , Intervalo Livre de Doença , Feminino , Humanos , Hepatopatias/terapia , Masculino , Pessoa de Meia-Idade , Prognóstico , Índice de Gravidade de Doença , Resultado do Tratamento
15.
Sci Adv ; 6(38)2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32948584

RESUMO

Electron transfer to an individual quantum dot promotes the formation of charged excitons with enhanced recombination pathways and reduced lifetimes. Excitons with only one or two extra charges have been observed and exploited for very efficient lasing or single-quantum dot light-emitting diodes. Here, by room-temperature time-resolved experiments on individual giant-shell CdSe/CdS quantum dots, we show the electrochemical formation of highly charged excitons containing more than 12 electrons and 1 hole. We report the control over intensity blinking, along with a deterministic manipulation of quantum dot photodynamics, with an observed 210-fold increase in the decay rate, accompanied by 12-fold decrease in the emission intensity, while preserving single-photon emission characteristics. These results pave the way for deterministic control over the charge state, and room-temperature decay rate engineering for colloidal quantum dot-based classical and quantum communication technologies.

16.
Micromachines (Basel) ; 11(1)2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-31968578

RESUMO

Interferometric effects between two counter-propagating beams incident on an optical system can lead to a coherent modulation of the absorption of the total electromagnetic radiation with 100% efficiency even in deeply subwavelength structures. Coherent perfect absorption (CPA) rises from a resonant solution of the scattering matrix and often requires engineered optical properties. For instance, thin film CPA benefits from complex nanostructures with suitable resonance, albeit at a loss of operational bandwidth. In this work, we theoretically and experimentally demonstrate a broadband CPA based on light-with-light modulation in epsilon-near-zero (ENZ) subwavelength films. We show that unpatterned ENZ films with different thicknesses exhibit broadband CPA with a near-unity maximum value located at the ENZ wavelength. By using Kerr optical nonlinearities, we dynamically tune the visibility and peak wavelength of the total energy modulation. Our results based on homogeneous thick ENZ media open a route towards on-chip devices that require efficient light absorption and dynamical tunability.

17.
Artigo em Inglês | MEDLINE | ID: mdl-30880943

RESUMO

BACKGROUND: Current pharmacological therapies for COPD improve quality of life and symptoms and reduce exacerbations. Given the progressive nature of COPD, it is arguably more important to understand whether the available therapies are able to delay clinical deterioration; the concept of "clinically important deterioration" (CID) has therefore been developed. We evaluated the efficacy of the single-inhaler triple combination beclometasone dipropionate, formoterol fumarate, and glycopyrronium (BDP/FF/G), using data from three large 1-year studies. METHODS: The studies compared BDP/FF/G to BDP/FF (TRILOGY), tiotropium (TRINITY), and indacaterol/glycopyrronium (IND/GLY; TRIBUTE). All studies recruited patients with symptomatic COPD, FEV1 <50%, and an exacerbation history. We measured the time to first CID and to sustained CID, an endpoint combining FEV1, St George's Respiratory Questionnaire (SGRQ), moderate-to-severe exacerbations, and death. The time to first CID was based on the first occurrence of any of the following: a decrease of ≥100 mL from baseline in FEV1, an increase of ≥4 units from baseline in SGRQ total score, the occurrence of a moderate/severe COPD exacerbation, or death. The time to sustained CID was defined as: a CID in FEV1 and/or SGRQ total score maintained at all subsequent visits, an exacerbation, or death. RESULTS: Extrafine BDP/FF/G significantly extended the time to first CID vs BDP/FF (HR 0.61, P<0.001), tiotropium (0.72, P<0.001), and IND/GLY (0.82, P<0.001), and significantly extended the time to sustained CID vs BDP/FF (HR 0.64, P<0.001) and tiotropium (0.80, P<0.001), with a numerical extension vs IND/GLY. CONCLUSION: In patients with symptomatic COPD, FEV1 <50%, and an exacerbation history, extrafine BDP/FF/G delayed disease deterioration compared with BDP/FF, tiotropium, and IND/GLY. TRIAL REGISTRATION: The studies are registered in ClinicalTrials.gov: TRILOGY, NCT01917331; TRINITY, NCT01911364; TRIBUTE, NCT02579850.


Assuntos
Corticosteroides/administração & dosagem , Agonistas de Receptores Adrenérgicos beta 2/administração & dosagem , Beclometasona/administração & dosagem , Broncodilatadores/administração & dosagem , Fumarato de Formoterol/administração & dosagem , Glicopirrolato/administração & dosagem , Pulmão/efeitos dos fármacos , Antagonistas Muscarínicos/administração & dosagem , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Administração por Inalação , Corticosteroides/efeitos adversos , Agonistas de Receptores Adrenérgicos beta 2/efeitos adversos , Idoso , Beclometasona/efeitos adversos , Broncodilatadores/efeitos adversos , Progressão da Doença , Combinação de Medicamentos , Feminino , Volume Expiratório Forçado , Fumarato de Formoterol/efeitos adversos , Glicopirrolato/efeitos adversos , Humanos , Pulmão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Antagonistas Muscarínicos/efeitos adversos , Nebulizadores e Vaporizadores , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/mortalidade , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Inquéritos e Questionários , Fatores de Tempo , Resultado do Tratamento
18.
Sci Rep ; 9(1): 7842, 2019 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-31110255

RESUMO

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.

19.
Sci Rep ; 8(1): 3862, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29497116

RESUMO

We present a detailed study of the second order nonlinearity of 2D (mono-atomic layer) dichalcogenide MoS2, both in the visible and in the IR regime, and test its potential for spontaneous parametric down-conversion (SPDC), the amplification of vacuum fluctuations mediated by optical nonlinearity. We develop a model of SPDC from a deeply subwavelength nonlinear medium, where phase matching conditions are completely relaxed, and make predictions about the rate of emitted photons, their momentum, polarisation and spectrum. We show that detection in the visible spectral region is hindered by the strong photoluminescence background. Moving to the IR regime we observe indications of SPDC by performing polarization, power dependence and lifetime measurements around 1560 nm. We show that the signal from a single monolayer is qualitatively different from that generated by multi-layer MoS2. Finally, we characterize the latter as a new kind of photo-luminescence emission which is enhanced at the edges of multi-layer MoS2.

20.
Int J Chron Obstruct Pulmon Dis ; 12: 3263-3271, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29138555

RESUMO

The GOLD 2017 strategy document recommends that the pharmacological management of COPD patients be based on the risk of future exacerbations and the severity of symptoms. A threshold of two moderate exacerbations or one hospitalization is used to define high-risk patients. The FORWARD study was a randomized, double-blind, parallel-group trial that compared 48 weeks' treatment with extrafine beclomethasone dipropionate plus formoterol fumarate (BDP-FF) versus FF in severe COPD patients with a history of one or more exacerbations in the previous year. The new GOLD 2017 recommendations mean that many patients in the FORWARD study are now reclassified as GOLD B. We conducted a post hoc analysis of the FORWARD study, in order to investigate the effects of extrafine BDP/FF in patients with one exacerbation in the previous year, focusing on those categorized as group B using the GOLD 2017 definition. The analysis showed a 35% reduction in exacerbation rate with an inhaled corticosteroid (ICS) + long-acting ß-agonist (LABA) versus LABA. We propose that ICS-LABA treatment is a therapeutic option for COPD patients with one exacerbation in the previous year.


Assuntos
Agonistas de Receptores Adrenérgicos beta 2/administração & dosagem , Beclometasona/administração & dosagem , Fumarato de Formoterol/administração & dosagem , Glucocorticoides/administração & dosagem , Pulmão/efeitos dos fármacos , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Administração por Inalação , Agonistas de Receptores Adrenérgicos beta 2/efeitos adversos , Agonistas de Receptores Adrenérgicos beta 2/química , Beclometasona/efeitos adversos , Beclometasona/química , Progressão da Doença , Método Duplo-Cego , Combinação de Medicamentos , Fumarato de Formoterol/efeitos adversos , Fumarato de Formoterol/química , Glucocorticoides/efeitos adversos , Glucocorticoides/química , Humanos , Pulmão/fisiopatologia , Tamanho da Partícula , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Fatores de Tempo , Resultado do Tratamento
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