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1.
Chemphyschem ; 25(8): e202300889, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38316612

RESUMEN

Developing electrocatalysts for urea oxidation reaction (UOR) works toward sustainably treating urea-enriched water. Without a clear understanding of how UOR products form, advancing catalyst performance is currently hindered. This work examines the thermodynamics of UOR pathways to produce N2, NO2 -, and NO3 - on a (0001) ß-Ni(OH)2 surface using density functional theory with the computational hydrogen electrode model. Our calculations show support for two major experimental observations: (1) N2 favours an intramolecular mechanism, and (2) NO2 -/NO3 - are formed in a 1 : 1 ratio with OCN-. In addition, we found that selectivity between N2 and NO2 -/NO3 - on our model surface appears to be controlled by two key factors, the atom that binds the surface intermediates to the surface and how they are deprotonated. These UOR pathways were also examined with a Cu dopant, revealing that an experimentally observed increased N2 selectivity may originate from increasing the limiting potential required to form NO2 -. This work builds towards developing a more complete atomic understanding of UOR at the surface of NiOxHy electrocatalysts.

2.
Artículo en Inglés | MEDLINE | ID: mdl-33833510

RESUMEN

Objective: To evaluate the perception of physicians on gender-specific differences in the diagnosis of chronic obstructive pulmonary disease (COPD) using a qualitative and anonymous questionnaire-based survey. Methods: The survey was conducted amongst respiratory physicians attending a standalone educational conference (29-30 September 2017) using the SpotMe® App. The 20-item standardized closed questionnaire had pre-coded responses to questions on physician's profile, and perception of COPD diagnosis and existing comorbidities between genders. All the responses were recorded anonymously. Results: Of 368 physicians who downloaded the SpotMe® App and had access to the survey, 132 (35.9%) completed the survey. Respondents were predominantly hospital-based (57.3%), aged 30-49 years (54.2%), male (56.5%), and from large cities (59.5%). 68.7% of physicians perceived the prevalence of COPD to be higher in men; over 50% of physicians perceived that women were more prone to the effects of smoking. More than 60% of physicians agreed that women experience more severe symptoms (anxiety and depression) and have reduced quality of life than men. Over 50% of physicians agreed that misdiagnosis/underdiagnosis of COPD in women was an important factor for gender-differences. Conclusion: Results from this survey indicate that the understanding of COPD burden in women varies among healthcare professionals.


Asunto(s)
Enfermedad Pulmonar Obstructiva Crónica , Fumar , Femenino , Humanos , Masculino , Percepción , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Enfermedad Pulmonar Obstructiva Crónica/epidemiología , Neumólogos , Calidad de Vida , Fumar/efectos adversos , Fumar/epidemiología , Encuestas y Cuestionarios
3.
Int J Chron Obstruct Pulmon Dis ; 15: 1831-1838, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32884253

RESUMEN

Background: Chronic obstructive pulmonary disease (COPD) exacerbations are difficult outcomes to measure in clinical trials. It would be valuable to be able to predict which patients are likely to benefit in terms of exacerbation prevention based on their early response in lung function and symptoms. Methods: This was a post-hoc analysis from the 52-week, randomized, double-blind, double-dummy, non-inferiority FLAME trial. Early clinically important improvement (ECII) was defined as achievement of minimal clinically important difference in trough forced expiratory volume in 1 second (FEV1; ≥100 mL increase) and one patient-reported outcome (PRO): either St. George's Respiratory Questionnaire for COPD (≥4-unit reduction; D1), or COPD assessment test (≥2-point reduction; D2) at Week 4 or 12. Results: Approximately 18-20% of patients achieved ECII at Week 4 or 12 post-randomization according to any of the two definitions. The rate of subsequent exacerbations was lower in patients who achieved ECII at Week 4 (D1: ratio of rates [95% CI], 0.85 [0.74 to 0.98]; D2, 0.88 [0.77 to 1.00]) or at Week 12 (D1, 0.85 [0.74 to 0.98]; D2, 0.86 [0.75 to 1.00]) versus patients not achieving ECII. Patients who achieved ECII experienced longer time-to-first exacerbation between Week 4 or 12 to end of study. More patients achieved ECII with indacaterol/glycopyrronium versus salmeterol/fluticasone according to both definitions at Week 4 (D1, odds ratio [95% CI], 1.69 [1.40 to 2.04]; D2, 1.61 [1.34 to 1.93]), and 12 (D1, 2.01 [1.66 to 2.44]; D2, 1.80 [1.48 to 2.18]). Conclusion: ECII is a novel composite endpoint, based on clinically relevant improvement in lung function and PROs in the early phase of treatment intervention that may predict subsequent exacerbation risk and may be used in clinical trials.


Asunto(s)
Enfermedad Pulmonar Obstructiva Crónica , Agonistas de Receptores Adrenérgicos beta 2/uso terapéutico , Broncodilatadores/efectos adversos , Método Doble Ciego , Volumen Espiratorio Forzado , Glicopirrolato/uso terapéutico , Humanos , Antagonistas Muscarínicos/efectos adversos , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , Resultado del Tratamiento
4.
Respir Res ; 21(1): 93, 2020 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-32321518

RESUMEN

BACKGROUND: COPD is a heterogeneous disease and patients may respond differently to therapies depending on baseline symptom burden. METHODS: This post-hoc analysis from the 52-week FLAME study investigated the impact of baseline symptom burden in terms of health status, dyspnoea, bronchitis status, eosinophil levels and smoking status on the subsequent risk of moderate or severe exacerbations. Health status was measured by St. George's Respiratory Questionnaire (SGRQ) score (higher ≥46.6 and lower < 46.6) and COPD Assessment Test (CAT) score (higher ≥17 and lower < 17); dyspnoea and bronchitis were assessed via an electronic diary (eDiary). Differential response to once-daily indacaterol/glycopyrronium (IND/GLY) 110/50 µg versus twice-daily salmeterol/fluticasone (SFC) 50/500 µg was assessed. RESULTS: Data from 3354 patients was analysed. The risk of exacerbations was lower in patients who had less severe health impairment (rate ratio [RR] [95% CI]): SGRQ-C, (0.88 [0.78, 0.99]); CAT, 0.85 [0.75, 0.96]) and lower dyspnoea (0.79 [0.69, 0.90]) at baseline versus those with more severe health impairment and higher dyspnoea, respectively. Compared with SFC, IND/GLY led to better prevention of moderate-to-severe exacerbations in the majority of groups studied. CONCLUSION: Patients with more severe health status impairment and greater symptom burden at baseline subsequently experienced more exacerbations in the FLAME study. IND/GLY was overall more effective in preventing exacerbations versus SFC, regardless of baseline symptom burden. Our results suggest that future studies on novel exacerbation therapies should consider targeting patients with higher symptom burden at baseline. CLINICAL TRIAL IDENTIFIER: NCT01782326.


Asunto(s)
Progresión de la Enfermedad , Combinación Fluticasona-Salmeterol/administración & dosificación , Volumen Espiratorio Forzado/efectos de los fármacos , Glicopirrolato/análogos & derivados , Estado de Salud , Indanos/administración & dosificación , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , Quinolonas/administración & dosificación , Anciano , Broncodilatadores/administración & dosificación , Método Doble Ciego , Combinación de Medicamentos , Femenino , Volumen Espiratorio Forzado/fisiología , Glicopirrolato/administración & dosificación , Humanos , Masculino , Persona de Mediana Edad , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Encuestas y Cuestionarios
5.
Int J Chron Obstruct Pulmon Dis ; 14: 1365-1376, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31417250

RESUMEN

Background: Qualitative research provides real-life information on patients' condition and facilitates informed design of future clinical studies. Objective: We used Online Communities as a qualitative research tool to evaluate the effect of cough and mucus on COPD patients. Methods: Two 2-week Online Communities were run in parallel in the UK and in the USA, including COPD patients with persistent cough and excessive mucus. Patients anonymously posted their responses to pre-assigned tasks, supervised and guided by a trained moderator. Five themes around the impact of cough and mucus were explored with new questions posted every 2-3 days. On the final day, high-level conclusions were shared with patients for feedback. Data were analyzed following the principles of grounded theory. Results: Twenty COPD patients (UK, n=10; USA, n=10) participated in the Online Communities. We found that cough and mucus disrupted COPD patients' lives at functional, emotional, social and economic levels. Patients created daily rituals and adjusted their lifestyle to cope with the impact of these symptoms. Patients identified themselves with our conclusions and saw the Online Community as an effective forum to share their experiences. Conclusion: Findings of our study add to the body of evidence on the negative impact of COPD symptoms and unmet needs of these patients.


Asunto(s)
Costo de Enfermedad , Tos , Moco , Enfermedad Pulmonar Obstructiva Crónica , Calidad de Vida , Actitud Frente a la Salud , Tos/etiología , Tos/fisiopatología , Tos/psicología , Femenino , Humanos , Masculino , Evaluación de Necesidades , Atención al Paciente/métodos , Atención al Paciente/psicología , Prioridad del Paciente , Distrés Psicológico , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Enfermedad Pulmonar Obstructiva Crónica/psicología , Investigación Cualitativa , Ajuste Social , Encuestas y Cuestionarios , Evaluación de Síntomas
6.
ERJ Open Res ; 5(1)2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30815470

RESUMEN

The association between clinically relevant changes in patient-reported outcomes (PROs) and forced expiratory volume in 1 s (FEV1) in patients with chronic obstructive pulmonary disease (COPD) has rarely been investigated. Using CRYSTAL, a 12-week open-label study in symptomatic, nonfrequently exacerbating patients with moderate COPD, we assessed at baseline the correlations between several PROs (Baseline Dyspnoea Index, modified Medical Research Council dyspnoea scale, COPD Assessment Test (CAT) and Clinical COPD Questionnaire (CCQ)), and between FEV1 and PROs. Associations between clinically relevant responses in FEV1, CAT, CCQ and Transition Dyspnoea Index (TDI) at week 12 were also assessed. Using data from 4324 patients, a strong correlation was observed between CAT and CCQ (rs=0.793) at baseline, with moderate or weak correlations between other PROs, and no correlation between FEV1 and any PRO. At week 12, 2774 (64.2%) patients were responders regarding TDI, CAT or CCQ, with 583 (13.5%) responding using all three measures. In comparison, 3235 (74.8%) were responders regarding FEV1, TDI, CAT or CCQ, with 307 (7.1%) responding concerning all four parameters. Increases in lung function were accompanied by clinically relevant improvements of PROs in a minority of patients. Our results also suggest that PROs are not interchangeable. Thus, the observed treatment success in a clinical trial may depend on the selected parameters.

7.
PLoS One ; 13(3): e0194434, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29558496

RESUMEN

BACKGROUND: Reduced lung function is common and associated with increased cardiovascular morbidity and mortality, even in asymptomatic individuals without diagnosed respiratory disease. Previous studies have identified relationships between lung function and cardiovascular structure in individuals with pulmonary disease, but the relationships in those free from diagnosed cardiorespiratory disease have not been fully explored. METHODS: UK Biobank is a prospective cohort study of community participants in the United Kingdom. Individuals self-reported demographics and co-morbidities, and a subset underwent cardiovascular magnetic resonance (CMR) imaging and spirometry. CMR images were analysed to derive ventricular volumes and mass. The relationships between CMR-derived measures and spirometry and age were modelled with multivariable linear regression, taking account of the effects of possible confounders. RESULTS: Data were available for 4,975 individuals, and after exclusion of those with pre-existing cardiorespiratory disease and unacceptable spirometry, 1,406 were included in the analyses. In fully-adjusted multivariable linear models lower FEV1 and FVC were associated with smaller left ventricular end-diastolic (-5.21ml per standard deviation (SD) change in FEV1, -5.69ml per SD change in FVC), end-systolic (-2.34ml, -2.56ml) and stroke volumes (-2.85ml, -3.11ml); right ventricular end-diastolic (-5.62ml, -5.84ml), end-systolic (-2.47ml, -2.46ml) and stroke volumes (-3.13ml, -3.36ml); and with lower left ventricular mass (-2.29g, -2.46g). Changes of comparable magnitude and direction were observed per decade increase in age. CONCLUSIONS: This study shows that reduced FEV1 and FVC are associated with smaller ventricular volumes and reduced ventricular mass. The changes seen per standard deviation change in FEV1 and FVC are comparable to one decade of ageing.


Asunto(s)
Bancos de Muestras Biológicas , Corazón/diagnóstico por imagen , Corazón/fisiopatología , Pulmón/fisiopatología , Imagen por Resonancia Magnética/métodos , Miocardio/patología , Femenino , Volumen Espiratorio Forzado , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Pruebas de Función Respiratoria/métodos , Espirometría/métodos , Volumen Sistólico , Reino Unido
8.
ERJ Open Res ; 2(4)2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28053974

RESUMEN

Rise in sputum complement (C3a, C5a) levels during COPD exacerbation is associated with recovery time http://ow.ly/ZaPj303xxPf.

9.
Respir Res ; 16: 16, 2015 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-25849856

RESUMEN

BACKGROUND: Exacerbations of non-cystic fibrosis bronchiectasis cause significant morbidity but there are few detailed data on their clinical course and associated physiological changes. The biology of an exacerbation has not been previously described. METHODS: This was a prospective observational cohort study of 32 outpatients with non-cystic fibrosis bronchiectasis conducted between August 2010 and August 2012. Patients completed a symptom diary card and measured their peak expiratory flow rate (PEFR) daily. Exacerbations were defined as oral antibiotic treatment taken for a worsening of respiratory symptoms. Symptoms and peak flow at exacerbation were analysed, and further measurements including the COPD Assessment Test (CAT) and inflammatory markers were also compared to baseline values. RESULTS: At baseline, health status was significantly related to lung function, prognostic severity and systemic inflammation. 51 exacerbations occurred in 22 patients. Exacerbation symptoms began a median (interquartile range) of 4 (2, 7) days before treatment started and the median exacerbation duration was 16 (10, 29) days. 16% had not recovered by 35 days. At exacerbation, mean PEFR dropped by 10.6% (95% confidence interval 6.9-14.2, p < 0.001) and mean CAT score increased by 6.3 units (3.6-9.1, p = 0.001), median symptom count by 4 (2.25, 6, p < 0.001), and mean CRP by 9.0mg/L (2.3-15.8, p = 0.011). Exacerbations where PEFR fell by ≥10% were longer with more symptoms at onset. CONCLUSION: Exacerbations of non-CF bronchiectasis are inflammatory events, with worsened symptoms, lung function and health status, and a prolonged recovery period. Symptom diary cards, PEFR and CAT scores are responsive to changes at exacerbation and may be useful tools for their detection and monitoring.


Asunto(s)
Bronquiectasia/diagnóstico , Pulmón/inmunología , Pulmón/fisiopatología , Neumonía/diagnóstico , Anciano , Antibacterianos/uso terapéutico , Biomarcadores/sangre , Bronquiectasia/sangre , Bronquiectasia/tratamiento farmacológico , Bronquiectasia/inmunología , Bronquiectasia/fisiopatología , Progresión de la Enfermedad , Femenino , Estado de Salud , Humanos , Mediadores de Inflamación/sangre , Pulmón/metabolismo , Masculino , Persona de Mediana Edad , Ápice del Flujo Espiratorio , Neumonía/sangre , Neumonía/tratamiento farmacológico , Neumonía/inmunología , Neumonía/fisiopatología , Valor Predictivo de las Pruebas , Estudios Prospectivos , Recuperación de la Función , Índice de Severidad de la Enfermedad , Espirometría , Encuestas y Cuestionarios , Factores de Tiempo , Resultado del Tratamiento
10.
Respir Res ; 15: 114, 2014 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-25218165

RESUMEN

BACKGROUND: There has been increasing interest in the use of newer, culture-independent techniques to study the airway microbiome of COPD patients. We investigated the relationships between the three common potentially pathogenic microorganisms (PPMs) Haemophilus influenzae, Streptococcus pneumoniae and Moraxella catarrhalis, as detected by quantitative PCR (qPCR), and inflammation and health status in stable patients in the London COPD cohort. METHODS: We prospectively collected sputum, serum and plasma samples for analysis of airway bacterial presence and load, and airway and systemic inflammation from 99 stable COPD patients between January 2011 and October 2012. Health status was measured with St George's Respiratory Questionnaire and COPD Assessment Test. RESULTS: Airway inflammation and plasma fibrinogen, but not C-reactive protein, were greater in samples with PPM detection (p < 0.001, p = 0.049 and p = 0.261, respectively). Increasing total bacterial load was associated with increasing airway (p < 0.01) but not systemic inflammation (p > 0.05). Samples with high total bacterial loads had significantly higher airway inflammation than both samples without PPM detection and those with lower loads. Haemophilus influenzae presence was associated with significantly higher levels of airway but not systemic inflammation for all given pathogen loads (p < 0.05), and was significantly greater than with other PPMs. No association was observed between inflammation and health status (p > 0.05). CONCLUSIONS: Airway and systemic inflammation, as measured by fibrinogen, is greater in stable COPD patients with PPMs detected using the culture-independent qPCR technique. The airway, but not systemic inflammatory response, appears to have a total pathogen-load threshold and appears attributable to Haemophilus influenzae. However, discordance between inflammation and health status was observed.


Asunto(s)
Haemophilus influenzae/aislamiento & purificación , Moraxella catarrhalis/aislamiento & purificación , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Enfermedad Pulmonar Obstructiva Crónica/microbiología , Streptococcus pneumoniae/aislamiento & purificación , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Recuento de Colonia Microbiana/métodos , Femenino , Haemophilus influenzae/genética , Humanos , Inflamación/diagnóstico , Inflamación/genética , Inflamación/microbiología , Masculino , Persona de Mediana Edad , Moraxella catarrhalis/genética , Estudios Prospectivos , Enfermedad Pulmonar Obstructiva Crónica/genética , Especificidad de la Especie , Streptococcus pneumoniae/genética
11.
Eur Respir J ; 44(1): 87-96, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24627537

RESUMEN

Human rhinovirus (HRV) infection is an important trigger of exacerbations of chronic obstructive pulmonary disease (COPD) but its role in determining exacerbation frequency phenotype or the time-course of HRV infection in naturally occurring exacerbations is unknown. Sputum samples from 77 patients were analysed by real-time quantitative PCR for both HRV (388 samples), and Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis (89 samples). Patients recorded worsening of respiratory symptoms on daily diary cards, from which exacerbations were identified. HRV prevalence and load at exacerbation presentation were significantly higher than in the stable state (prevalence 53.3% versus 17.2%, respectively; p<0.001) but 0% by day 35 post-exacerbation. HRV load was higher in patients with cold symptoms (p=0.046) or sore throats (p=0.006) than those without. 73% of bacterium-negative but HRV-positive exacerbations were bacterium-positive by day 14. Patients with HRV detected at exacerbation had a higher exacerbation frequency (interquartile range) of 3.01 (2.02-5.30) per year compared with patients without HRV (2.51 (2.00-3.51)) (p=0.038). HRV prevalence and load increased at COPD exacerbation, and resolved during recovery. Frequent exacerbators were more likely to experience HRV infection. Secondary bacterial infection is common after HRV infection, and provides a possible mechanism for exacerbation recurrence and a potential target for novel therapies.


Asunto(s)
Infecciones por Picornaviridae/complicaciones , Enfermedad Pulmonar Obstructiva Crónica/complicaciones , Rhinovirus , Anciano , Infecciones Bacterianas/complicaciones , Femenino , Volumen Espiratorio Forzado , Haemophilus influenzae , Humanos , Londres , Masculino , Persona de Mediana Edad , Moraxella catarrhalis , Infecciones por Picornaviridae/fisiopatología , Reacción en Cadena de la Polimerasa , Prevalencia , Estudios Prospectivos , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Enfermedad Pulmonar Obstructiva Crónica/virología , Recurrencia , Fumar , Espirometría , Esputo/microbiología , Esputo/virología , Streptococcus pneumoniae , Resultado del Tratamiento , Capacidad Vital
12.
Thorax ; 67(12): 1075-80, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22863758

RESUMEN

BACKGROUND: Prevalence and load of airway bacteria in stable and exacerbated chronic obstructive pulmonary disease (COPD) has been previously studied using microbiological culture. Molecular techniques, such as quantitative PCR (qPCR), may be more informative. METHODS: In this study, 373 sputum samples from 134 COPD outpatients were assessed for prevalence and load of typical airway bacteria (Haemophilus influenzae, Streptococcus pneumoniae, Moraxella catarrhalis) by multiplex qPCR, with 176 samples analysed for atypical bacteria. Paired stable and exacerbation typical bacteria data were compared in 52 patients. We compared routine culture with qPCR in 177/373 samples. RESULTS: Typical bacteria were more prevalent in exacerbation than stable-state paired samples: 30/52 (57.7%) vs. 14/52 (26.9%); p=0.001. In patients who were bacteria-positive at both time points, mean (±1 SEM) load was significantly higher at exacerbation than stable state (108.5(±0.3) vs. 107.2(±0.5) cfu/ml), constituting a 20-fold increase (p=0.011). qPCR was more discriminatory at detecting typical bacteria than microbiological culture (prevalence 59.3% vs. 24.3%; p<0.001). At stable state, higher airway bacterial load correlated with more severe airflow limitation (FEV(1)%predicted) (r=-0.299; p=0.033) and higher inhaled corticosteroid dosage (r=0.382; p=0.008). Mean C-reactive protein was higher in bacterial-associated exacerbations (35.0 Vs 25.1 mg/L; p=0.032). CONCLUSIONS: Airway bacterial prevalence and load increase at COPD exacerbations and are an aetiological factor. qPCR is more discriminatory than culture, identifying higher airway bacterial prevalence. Exacerbations associated with bacterial detection showed a higher mean C-reactive protein level. In the stable state, airway bacterial load is related to more severe airflow limitation and higher inhaled corticosteroid dosage used.


Asunto(s)
Haemophilus influenzae/aislamiento & purificación , Moraxella catarrhalis/aislamiento & purificación , Reacción en Cadena de la Polimerasa/métodos , Enfermedad Pulmonar Obstructiva Crónica/microbiología , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Streptococcus pneumoniae/aislamiento & purificación , Anciano , Análisis de Varianza , Distribución de Chi-Cuadrado , Femenino , Humanos , Modelos Lineales , Londres , Masculino , Prevalencia , Pruebas de Función Respiratoria , Esputo/microbiología
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