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1.
Respir Res ; 21(Suppl 1): 102, 2020 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-32907566

RESUMO

BACKGROUND: Navafenterol (AZD8871) is a dual-pharmacology muscarinic antagonist ß2-agonist (MABA) molecule in development for the treatment of chronic obstructive pulmonary disease (COPD). The pharmacodynamics, safety and tolerability of single doses of navafenterol were investigated in patients with moderate to severe COPD. METHODS: This was a randomized, five-way complete cross-over study. Patients received single doses of navafenterol 400 µg, navafenterol 1800 µg and placebo (all double-blind) and indacaterol 150 µg and tiotropium 18 µg (both open-label active comparators). The primary pharmacodynamic endpoint was change from baseline in trough forced expiratory volume in 1 s (FEV1) on day 2. Safety and tolerability were monitored throughout. RESULTS: Thirty-eight patients were randomized and 28 (73.7%) completed the study. Navafenterol 400 µg and 1800 µg demonstrated statistically significant improvements vs placebo in change from baseline in trough FEV1 (least squares mean [95% confidence interval]: 0.111 [0.059, 0.163] L and 0.210 [0.156, 0.264] L, respectively, both P < .0001). The changes were significantly greater with navafenterol 1800 µg vs the active comparators (least squares mean treatment difference: 0.065-0.069 L, both P < .05). The frequency of treatment-emergent adverse events was similar for placebo and the active comparators (range 34.4-37.5%), slightly higher for navafenterol 400 µg (52.9%), and lowest for navafenterol 1800 µg (22.6%). CONCLUSIONS: Both doses of navafenterol demonstrated sustained bronchodilation over 24 h. Navafenterol was well tolerated and no safety concerns were raised. TRIAL REGISTRY: ClinicalTrials.gov ; No.: NCT02573155 ; URL: www.clinicaltrials.gov . Registered 9th October, 2015.

2.
Respir Res ; 21(Suppl 1): 212, 2020 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-32907575

RESUMO

BACKGROUND: Navafenterol (AZD8871) is a novel, long-acting, dual-pharmacology (muscarinic receptor antagonist and ß2-adrenoceptor agonist) molecule in development for chronic obstructive pulmonary disease and asthma. METHODS: These two phase I, randomised, single-blind, multiple-ascending-dose studies evaluated inhaled navafenterol and placebo (3:1 ratio) in healthy, male, non-Japanese (study A; NCT02814656) and Japanese (study B; NCT03159442) volunteers. In each study, volunteers were dosed in three cohorts, allowing gradual dose escalation from 300 µg to 600 µg to 900 µg. The primary objective was to investigate the safety and tolerability of navafenterol at steady state. Pharmacokinetics were also assessed. RESULTS: Twenty-four volunteers completed each study (navafenterol, n = 6; placebo, n = 2 in each cohort). There were no deaths, serious adverse events (AEs) or treatment-emergent AEs (TEAEs) leading to discontinuation of navafenterol. The most frequent TEAEs were vessel puncture-site bruise (placebo, n = 2; navafenterol 900 µg; n = 3) in study A and diarrhoea (placebo, n = 1; navafenterol 300 µg, n = 2; navafenterol 900 µg, n = 3) in study B. No dose-response relationship was observed for TEAEs. There was a dose-dependent increase in mean heart rate on day 16 in both studies. The pharmacokinetics of navafenterol were similar between non-Japanese and Japanese volunteers. CONCLUSIONS: Multiple ascending doses of navafenterol were well-tolerated and the safety and pharmacokinetics of navafenterol were similar in non-Japanese and Japanese volunteers. The findings support navafenterol clinical development. TRIAL REGISTRATION: ClinicalTrials.gov ; Nos.: NCT02814656 and NCT03159442; URL: www.clinicaltrials.gov .

3.
Respir Res ; 21(Suppl 1): 211, 2020 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-32907576

RESUMO

BACKGROUND: Navafenterol (AZD8871) is an inhaled long-acting dual-pharmacology muscarinic antagonist/ß2-adrenoceptor agonist (MABA) in development for the treatment of obstructive airways diseases. The safety, tolerability, pharmacodynamics, and pharmacokinetics of navafenterol were investigated in patients with mild asthma. METHODS: This was a randomised, single-blind, placebo-controlled, single-ascending-dose study. Patients were randomly assigned to one of two cohorts which evaluated escalating doses of navafenterol (50-2100 µg) in an alternating manner over three treatment periods. The primary pharmacodynamic endpoint was the change from pre-dose baseline in trough forced expiratory volume in 1 s (FEV1) for each treatment period. RESULTS: Sixteen patients were randomised; 15 completed treatment. Data from all 16 patients were analysed. The maximum tolerated dose was not identified, and all doses of navafenterol were well tolerated. The most frequently reported treatment-emergent adverse events (TEAEs) were headache (n = 10, 62.5%) and nasopharyngitis (n = 7, 43.8%). No TEAEs were serious, fatal, or led to discontinuation, and no dose dependency was identified. Navafenterol demonstrated a dose-ordered bronchodilatory response with a rapid onset of action (within 5 min post-dose). Doses ≥200 µg resulted in improvements in trough FEV1 (mean change from baseline range 0.186-0.463 L) with sustained bronchodilation for 24-36 h. Plasma concentrations increased in a dose-proportional manner, peaking ~ 1 h post-dose, with a derived terminal elimination half-life of 15.96-23.10 h. CONCLUSIONS: In this study navafenterol was generally well tolerated with a rapid onset of action which was sustained over 36 h. TRIAL REGISTRATION: ClinicalTrials.gov; No.: NCT02573155.

4.
Chem Soc Rev ; 49(18): 6694-6732, 2020 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-32820300

RESUMO

Metal-organic frameworks (MOFs) are a class of porous crystalline materials showing great potential for applications such as catalysis, gas storage, molecular separations, energy storage and drug delivery. The properties that render them interesting stem from their structure (e.g. morphology, porosity or metal coordination and geometry). Thus, gaining a deeper understanding strongly relies on the availability and adequate use of advanced characterization tools, which can interrogate MOFs under realistic synthesis as well as catalysis (or sorption) conditions. Herein, we present an overview of the various characterization techniques specifically suitable for the study on the underlying chemistry of the formation mechanisms and adsorption properties of three archetypal MOFs, namely MIL-100, ZIF-8 and HKUST-1. A section on using MOFs as supports for metal atoms or complexes that can be used for catalysis on the robust Zr6 nodes of UiO-66 or NU-1000, and the characterization techniques used thereof, is presented as well. In addition, we discuss recent developments on the application of nano-spectroscopic characterization for MOF thin-films and explore the potential of MOFs as model systems in catalysis. The conclusions and outlook provide future research possibilities in the field of MOF characterization.

5.
Pediatr Infect Dis J ; 38(12): 1230-1235, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31738339

RESUMO

BACKGROUND: Congenital cytomegalovirus infection (CMVc) affects 0.7%-6% of recent births. Among its clinical manifestations are low weight and length at birth. OBJECTIVE: Describe the growth patterns of children with CMVc in their early years. METHODS: Observational, multicenter study of patients with CMVc. Anthropometric data were collected during the first 2 years of life and compared with World Health Organization standards. RESULTS: Anthropometric characteristics of 383 children with CMVc were studied, of which 198 (51%) were symptomatic at birth. At birth, 9% were small for gestational age (SGA) in terms of their weight and length and 17% had microcephaly. At 24 ± 3 months, 10% had a weight and length ≤2 SD, and 13% a head circumference ≤2 SD. Of those who were SGA at birth, at 24 ± 3 months >20% remained at ≤2 SD of their weight and length. Conversely, 75% of children with low weight or length at 24 ± 3 had not been SGA at birth. 20% of infants with microcephaly at birth remained with microcephaly, and 10% of those without microcephaly developed it at 24 ± 3 months. The average growth rate in length and weight was normal. Patients who were symptomatic at birth, premature and with motor and neurocognitive impairment had a significantly higher risk of low weight and length at 24 ± 3 months. CONCLUSION: Around 10% of children with CMVc are at ≤2 SD in weight, length and head circumference at 24 ± 3 months. The lack of adequate growth is associated with symptoms at birth, prematurity and motor and neurocognitive impairment. Growth impairment could be incorporated into the symptomatic spectrum of CMVc.

6.
Proc Natl Acad Sci U S A ; 116(31): 15350-15355, 2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-31311870

RESUMO

The Mpemba effect occurs when a hot system cools faster than an initially colder one, when both are refrigerated in the same thermal reservoir. Using the custom-built supercomputer Janus II, we study the Mpemba effect in spin glasses and show that it is a nonequilibrium process, governed by the coherence length ξ of the system. The effect occurs when the bath temperature lies in the glassy phase, but it is not necessary for the thermal protocol to cross the critical temperature. In fact, the Mpemba effect follows from a strong relationship between the internal energy and ξ that turns out to be a sure-tell sign of being in the glassy phase. Thus, the Mpemba effect presents itself as an intriguing avenue for the experimental study of the coherence length in supercooled liquids and other glass formers.

8.
Sci Adv ; 4(9): eaau1698, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30255154

RESUMO

The development of new membranes with high H2 separation performance under industrially relevant conditions (high temperatures and pressures) is of primary importance. For instance, these membranes may facilitate the implementation of energy-efficient precombustion CO2 capture or reduce energy intensity in other industrial processes such as ammonia synthesis. We report a facile synthetic protocol based on interfacial polymerization for the fabrication of supported benzimidazole-linked polymer membranes that display an unprecedented H2/CO2 selectivity (up to 40) at 423 K together with high-pressure resistance and long-term stability (>800 hours in the presence of water vapor).

9.
Soft Matter ; 14(25): 5222-5234, 2018 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-29892754

RESUMO

Motivated by the mean field prediction of a Gardner phase transition between a "normal glass" and a "marginally stable glass", we investigate the off-equilibrium dynamics of three-dimensional polydisperse hard spheres, used as a model for colloidal or granular glasses. Deep inside the glass phase, we find that a sharp crossover pressure PG separates two distinct dynamical regimes. For pressure P < PG, the glass behaves as a normal solid, displaying fast dynamics that quickly equilibrate within the glass free energy basin. For P > PG, instead, the dynamics become strongly anomalous, displaying very large equilibration timescales, aging, and a constantly increasing dynamical susceptibility. The crossover at PG is strongly reminiscent of the one observed in three-dimensional spin-glasses in an external field, suggesting that the two systems could be in the same universality class, consistent with theoretical expectations.

10.
Adv Mater ; 30(26): e1707234, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29774609

RESUMO

During the last decade, the synthesis and application of metal-organic framework (MOF) nanosheets has received growing interest, showing unique performances for different technological applications. Despite the potential of this type of nanolamellar materials, the synthetic routes developed so far are restricted to MOFs possessing layered structures, limiting further development in this field. Here, a bottom-up surfactant-assisted synthetic approach is presented for the fabrication of nanosheets of various nonlayered MOFs, broadening the scope of MOF nanosheets application. Surfactant-assisted preorganization of the metallic precursor prior to MOF synthesis enables the manufacture of nonlayered Al-containing MOF lamellae. These MOF nanosheets are shown to exhibit a superior performance over other crystal morphologies for both chemical sensing and gas separation. As revealed by electron microscopy and diffraction, this superior performance arises from the shorter diffusion pathway in the MOF nanosheets, whose 1D channels are oriented along the shortest particle dimension.

11.
Chemistry ; 24(29): 7498-7506, 2018 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-29709084

RESUMO

Because of their high tunability and surface area, metal-organic frameworks (MOFs) show great promise as supports for metal nanoparticles. Depending on the synthesis route, MOFs may contain defects. Here, we show that highly crystalline MIL-100(Fe) and disordered Basolite® F300, with identical iron 1,3,5-benzenetricarboxylate composition, exhibit very divergent properties when used as a support for Pd nanoparticle deposition. While MIL-100(Fe) shows a regular MTN-zeotype crystal structure with two types of cages, Basolite® F300 lacks long-range order beyond 8 Šand has a single-pore system. The medium-range configurational linker-node disorder in Basolite® F300 results in a reduced number of Lewis acid sites, yielding more hydrophobic surface properties compared to hydrophilic MIL-100(Fe). The hydrophilic/hydrophobic nature of MIL-100(Fe) and Basolite® F300 impacts the amount of Pd and particle size distribution of Pd nanoparticles deposited during colloidal synthesis and dry impregnation methods, respectively. It is suggested that polar (apolar) solvents/precursors attractively interact with hydrophilic (hydrophobic) MOF surfaces, allowing tools at hand to increase the level of control over, for example, the nanoparticle size distribution.

12.
Chronic Obstr Pulm Dis ; 5(1): 5-15, 2018 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-29629400

RESUMO

Introduction: Chronic obstructive pulmonary disease (COPD) is a heterogeneous illness characterized by persistent airflow obstruction and exacerbations. Patients typically experience a decline in lung function, increasingly impaired health-related quality of life, and high mortality. Poor lung function and exacerbations are associated with an increased risk of cardiovascular (CV) and cerebrovascular events, and approximately 30% of patients with COPD die from CV­related disease. Treatment with inhaled long-acting bronchodilators, such as long-acting muscarinic antagonists (LAMAs), is recommended; however, some studies have suggested that LAMAs may increase the risk of CV events. As patients with CV and cerebrovascular conditions are often excluded from clinical trials, an evaluation of the safety of COPD treatments in an at-risk population is vital. Aclidinium bromide is a LAMA approved for the long-term maintenance treatment of COPD. Methods and Objectives: The Phase 4, multicenter, double-blind, randomized, placebo-controlled, parallel-group Aclidinium Bromide on Long-Term Cardiovascular Safety and COPD Exacerbations in PatieNTs with Moderate to Very Severe COPD (ASCENT COPD) study (NCT01966107) is being conducted at 500 sites in the United States and Canada. The primary objectives are to evaluate the long-term effects of twice-daily aclidinium bromide 400 µg on CV safety and exacerbations in patients with moderate to very severe COPD with a history of cerebrovascular, coronary, or peripheral artery disease, or the presence of ≥2 atherothrombotic risk factors. The primary safety and efficacy variables are time to first major adverse CV event (MACE) (on-study analysis) and rate of moderate to severe COPD exacerbations during the first year of treatment (on-treatment analysis), respectively. The study will be terminated after approximately 122 MACE have occurred.

13.
Nanoscale ; 10(15): 6884-6891, 2018 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-29520398

RESUMO

Recently various porous organic frameworks (POFs, crystalline or amorphous materials) have been discovered, and used for a wide range of applications, including molecular separations and catalysis. Silicon nanowires (SiNWs) have been extensively studied for diverse applications, including as transistors, solar cells, lithium ion batteries and sensors. Here we demonstrate the functionalization of SiNW surfaces with POFs and explore its effect on the electrical sensing properties of SiNW-based devices. The surface modification by POFs was easily achieved by polycondensation on amine-modified SiNWs. Platinum nanoparticles were formed in these POFs by impregnation with chloroplatinic acid followed by chemical reduction. The final hybrid system showed highly enhanced sensitivity for methanol vapour detection. We envisage that the integration of SiNWs with POF selector layers, loaded with different metal nanoparticles will open up new avenues, not only in chemical and biosensing, but also in separations and catalysis.

14.
Angew Chem Int Ed Engl ; 57(18): 5156-5160, 2018 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-29465815

RESUMO

Through IR microimaging the spatially and temporally resolved development of the CO2 concentration in a ZIF-8@6FDA-DAM mixed matrix membrane (MMM) was visualized during transient adsorption. By recording the evolution of the CO2 concentration, it is observed that the CO2 molecules propagate from the ZIF-8 filler, which acts as a transport "highway", towards the surrounding polymer. A high-CO2 -concentration layer is formed at the MOF/polymer interface, which becomes more pronounced at higher CO2 gas pressures. A microscopic explanation of the origins of this phenomenon is suggested by means of molecular modeling. By applying a computational methodology combining quantum and force-field based calculations, the formation of microvoids at the MOF/polymer interface is predicted. Grand canonical Monte Carlo simulations further demonstrate that CO2 tends to preferentially reside in these microvoids, which is expected to facilitate CO2 accumulation at the interface.

15.
Artigo em Inglês | MEDLINE | ID: mdl-28971615

RESUMO

Abediterol is a once-daily, long-acting ß2 -adrenergic agonist in development for the treatment of asthma and chronic obstructive pulmonary disease. We assessed the efficacy, safety, and tolerability of three dose levels of abediterol, given once daily for 7 days in patients with stable, persistent asthma. This was an ascending-dose, three-period incomplete crossover study design investigating three dose levels of abediterol versus placebo (EudraCT No. 2008-003732-38). Twenty-eight male patients (25-59 years) were randomized to one of four treatment sequences (1:1:1:1). Follow-up was 7 days after final treatment. Spirometry was performed regularly up to 24 h postdose Day 1, up to 36 h postdose Day 7, and at follow-up. Vital signs, 12-lead electrocardiogram, and clinical laboratory tests were recorded throughout. Abediterol 2.5, 5, and 10 µg provided clinically and statistically significant improvements from baseline (predose, Day 1) in trough forced expiratory volume in 1 sec (FEV1 ) versus placebo on Day 7 (primary endpoint) of 334, 365, and 294 mL, respectively (all P < 0.01), and peak FEV1 versus placebo on Day 7 of 364 (P < 0.001), 403 (P < 0.001), and 375 mL (P < 0.01), respectively. Days 1 and 7 area under the curve (AUC) parameters within each abediterol group were similar for AUC0-6 , AUC0-12 , AUC0-24 , and AUC12-24 , with dose-dependent effects observed on Day 1. Abediterol (2.5-10 µg) demonstrated a good safety and tolerability profile. Abediterol 2.5, 5, and 10 µg once daily achieved statistically and clinically significant improvements in pulmonary function versus placebo over 7 days and demonstrated a safety and tolerability profile comparable with placebo.


Assuntos
Agonistas de Receptores Adrenérgicos beta 2/administração & dosagem , Agonistas de Receptores Adrenérgicos beta 2/efeitos adversos , Asma/tratamento farmacológico , Quinolonas/administração & dosagem , Quinolonas/efeitos adversos , Agonistas de Receptores Adrenérgicos beta 2/farmacologia , Adulto , Asma/fisiopatologia , Estudos Cross-Over , Relação Dose-Resposta a Droga , Esquema de Medicação , Volume Expiratório Forçado/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Quinolonas/farmacologia , Espirometria , Resultado do Tratamento
16.
J Chem Phys ; 147(8): 084704, 2017 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-28863547

RESUMO

We present a three-dimensional Ising model where lines of equal spins are frozen such that they form an ordered framework structure. The frame spins impose an external field on the rest of the spins (active spins). We demonstrate that this "porous Ising model" can be seen as a minimal model for condensation transitions of gas molecules in metal-organic frameworks. Using Monte Carlo simulation techniques, we compare the phase behavior of a porous Ising model with that of a particle-based model for the condensation of methane (CH4) in the isoreticular metal-organic framework IRMOF-16. For both models, we find a line of first-order phase transitions that end in a critical point. We show that the critical behavior in both cases belongs to the 3D Ising universality class, in contrast to other phase transitions in confinement such as capillary condensation.

18.
Proc Natl Acad Sci U S A ; 114(8): 1838-1843, 2017 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-28174274

RESUMO

We have performed a very accurate computation of the nonequilibrium fluctuation-dissipation ratio for the 3D Edwards-Anderson Ising spin glass, by means of large-scale simulations on the special-purpose computers Janus and Janus II. This ratio (computed for finite times on very large, effectively infinite, systems) is compared with the equilibrium probability distribution of the spin overlap for finite sizes. Our main result is a quantitative statics-dynamics dictionary, which could allow the experimental exploration of important features of the spin-glass phase without requiring uncontrollable extrapolations to infinite times or system sizes.

19.
Chemistry ; 22(41): 14467-70, 2016 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-27535016

RESUMO

Mixed-matrix membranes (MMMs) comprising Matrimid and a microporous azine-linked covalent organic frameworks (ACOF-1) were prepared and tested in the separation of CO2 from an equimolar CO2 /CH4 mixture. The COF-based MMMs show a more than doubling of the CO2 permeability upon 16 wt % ACOF-1 loading together with a slight increase in selectivity compared to the bare polymer. These results show the potential of COFs in the preparation of MMMs.

20.
Eur Respir J ; 48(4): 1030-1039, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27492833

RESUMO

The efficacy and safety of twice-daily aclidinium bromide/formoterol fumarate was compared with that of salmeterol/fluticasone propionate in patients with stable, moderate-to-severe chronic obstructive pulmonary disease (COPD).AFFIRM COPD (Aclidinium and Formoterol Findings in Respiratory Medicine COPD) was a 24-week, double-blind, double-dummy, active-controlled study. Patients were randomised (1:1) to aclidinium/formoterol 400/12 µg twice-daily via Genuair/Pressair or salmeterol/fluticasone 50/500 µg twice-daily via Accuhaler. The primary end-point was peak forced expiratory volume in 1 s (FEV1) at week 24. Other end-points included Transition Dyspnoea Index (TDI) focal score at week 24, TDI and St George's Respiratory Questionnaire (SGRQ) responders, COPD Assessment Test and SGRQ scores, assessment of COPD symptoms and exacerbations, use of reliever medication, and device preference. Adverse events were monitored throughout.In total, 933 patients were eligible (mean age 63.4 years, 65.1% male). Aclidinium/formoterol was superior to salmeterol/fluticasone in peak FEV1 and noninferior in TDI. Health status and reduction in exacerbation risk were similar in both groups. While both treatments were well tolerated, pneumonia occurred less frequently with aclidinium/formoterol than salmeterol/fluticasone.In stable COPD, aclidinium/formoterol significantly improved bronchodilation versus salmeterol/fluticasone, with equivalent benefits in symptom control and reduction in exacerbation risk. Both treatments were well tolerated and treatment-related adverse events were less common with aclidinium/formoterol.


Assuntos
Combinação Fluticasona-Salmeterol/administração & dosagem , Fumarato de Formoterol/administração & dosagem , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Tropanos/administração & dosagem , Adulto , Idoso , Broncodilatadores/farmacologia , Método Duplo-Cego , Feminino , Fluticasona/administração & dosagem , Volume Expiratório Forçado , Humanos , Masculino , Pessoa de Meia-Idade , Pneumologia , Xinafoato de Salmeterol/administração & dosagem , Fumar , Espirometria , Inquéritos e Questionários , Resultado do Tratamento
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