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1.
Phys Chem Chem Phys ; 26(19): 14244-14255, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38690716

RESUMEN

In this work, PbPd0.9V0.1O2 and PbPd0.9Gd0.1O2 thin films with (002) preferred orientation were prepared using a pulsed laser deposition technique. The temperature dependence of resistivities ρI(T) was investigated under various applied DC currents. Colossal electroresistance (CER) effects were found in PbPd0.9V0.1O2 and PbPd0.9Gd0.1O2. It was found that the positive CER values of PbPd0.9V0.1O2 and PbPd0.9Gd0.1O2 reach 3816% and 154% for I = 1.00 µA at 10 K, respectively. In addition, the ρI(T) cycle curves of PbPd0.9V0.1O2 and PbPd0.9Gd0.1O2 thin films showed a critical temperature similar to that of PbPdO2 (Tc = 260 K). Particularly, charge transfer between O1- and O2- was confirmed by in situ XPS. Additionally, based on first-principles calculations and internal electric field models, the CER and magnetic sources in PbPd0.9V0.1O2 and PbPd0.9Gd0.1O2 can be well explained. Finally, it was found that thin film samples doped with V and G ions exhibit weak localization (WL) and weak anti-localization (WAL) quantum transport properties. Ion doping leads to a transition from WAL to WL. The study results indicate that PbPdO2, one of the few oxide topological insulators, can exhibit novel quantum transport behavior after ion doping.

2.
Dalton Trans ; 53(2): 765-771, 2024 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-38086693

RESUMEN

Na-ion batteries (NIBs) have attracted great interest as a possible technology for grid-scale energy storage for the past few years owing to the wide distribution, low cost and environmental friendliness of sodium resources and similar chemical mechanisms to those of established Li-ion batteries (LIBs). Nonetheless, the implementation of NIBs is seriously hindered because of their low rate capability and cycling stability. This is mainly because the large ionic size of Na+ can reduce the structural stability and cause sluggish reaction kinetics of electrode materials. Herein, three-dimensional nanoarchitectured coral-like CoSe2@N-doped carbon (CL-CoSe2@NC) was synthesized through solvothermal and selenizing techniques. As a result, CL-CoSe2@NC for NIBs at 2 A g-1 exhibits an ultrahigh specific capacity of 345.4 mA h g-1 after 2800 cycles and a superhigh initial coulombic efficiency (ICE) of 93.1%. Ex situ XRD, HRTEM, SAED and XPS were executed to study the crystal structure evolution between Na and CoSe2 during sodiation/de-sodiation processes. The aforementioned results indicate that the improved sodium storage property of CL-CoSe2@NC could be attributed to better electrode kinetics and a stable SEI film because of the 3D nanoarchitecture and the existence of the NC layer.

3.
RSC Adv ; 12(44): 28341-28348, 2022 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-36320523

RESUMEN

Owing to the natural abundance and low-cost of sodium, sodium-ion batteries offer advantages for next-generation portable electronic devices and smart grids. However, the development of anode materials with long cycle life and high reversible capacity is still a great challenge. Herein, we report a yolk-shell structure composed of N,P co-doped carbon as the shell and CoP nanowires as the yolk (YS-CoP@NPC) for a hierarchically nanoarchitectured anode for improved sodium storage performance. Benefitting from the 1D hollow structure, the YS-CoP@NPC electrode exhibits an excellent cycling stability with a reversibly capacity of 211.5 mA h g-1 at 2 A g-1 after 1000 cycles for sodium storage. In-depth characterization by ex situ X-ray photoelectron spectroscopy and work function analysis revealed that the enhanced sodium storage property of YS-CoP@NPC might be attributed to the stable solid electrolyte interphase film, high electronic conductivity and better Na+ diffusion kinetics.

4.
Phys Chem Chem Phys ; 24(48): 29520-29527, 2022 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-36448469

RESUMEN

Ferric oxide (Fe2O3) is an attractive anode material for lithium-ion batteries (LIBs) with a high theoretical capacity of 1005 mA h g-1. However, its practical application is greatly restrained by the rapid capacity fading caused by the large volume expansion upon lithiation. To address this issue, we have designed and synthesized a unique yolk-shell Fe2O3/N-doped carbon hybrid structure (YS-Fe2O3@NC) with rich oxygen vacancies for robust lithium storage. The obtained results show that YS-Fe2O3@NC delivers a high reversible capacity of 578 mA h g-1 after 300 cycles at a current density of 5 A g-1, about 11 times that (53.7 mA h g-1) of pristine Fe2O3. Furthermore, a high specific capacity of 300.5 mA h g-1 even at 10 A g-1 is achieved. The high reversible capacities, excellent rate capability and cycle stability of YS-Fe2O3@NC might be attributed to the elaborate yolk-shell nanoarchitecture. Moreover, electron percolation and a local built-in electric field induced by oxygen vacancies in the Fe2O3 matrix could also enhance the kinetics of Li+ insertion/deinsertion.

5.
RSC Adv ; 8(74): 42438-42445, 2018 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-35558412

RESUMEN

3D plum candy-like NiCoMnO4 microspheres have been prepared via ultrasonic spraying and subsequently wrapped by graphene through electrostatic self-assembly. The as-prepared NiCoMnO4 powders show hollow structures and NiCoMnO4@graphene exhibits excellent electrochemical performances in terms of rate performance and cycling stability, achieving a high reversible capacity of 844.6 mA h g-1 at a current density of 2000 mA g-1. After 50 cycles at 1000 mA g-1, NiCoMnO4@graphene delivers a reversible capacity of 1045.1 mA h g-1 while the pristine NiCoMnO4 only has a capacity of 143.4 mA h g-1. The hierarchical porous structure helps to facilitate electron transfer and Li-ion kinetic diffusion by shortening the Li-ion diffusion length, accommodating the mechanical stress and volume change during the Li-ion insertion/extraction processes. Analysis from the electrochemical performances reveals that the enhanced performances could be also attributed to the reduced charge-transfer resistance and enhanced Li-ion diffusion kinetics because of the graphene-coating. Moreover, Schottky electric field, due to the difference in work function between graphene and NiCoMnO4, might be favorable for the redox activity of the NiCoMnO4. In light of the excellent electrochemical performance and simple preparation, we believe that 3D plum candy-like NiCoMnO4@graphene composites are expected to be applied as a promising anode materials for high-performance lithium ion batteries.

6.
PLoS One ; 11(3): e0150838, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26998756

RESUMEN

OBJECTIVE: To analyze plasma myostatin levels and investigate their relationship with right ventricular (RV) function in patients with cor pulmonale secondary to chronic obstructive pulmonary disease (COPD). METHODS: The study recruited 81 patients with advanced COPD and 40 age-matched controls. The patients were divided into two groups: those with cor pulmonale and those without. Echocardiography was used to evaluate RV function and morphology, and the value of tricuspid annular plane systolic excursion (TAPSE) less than 16 mm was considered RV dysfunction. Plasma myostatin levels were analyzed by enzyme-linked immunosorbent assay, and B-type natriuretic peptide (BNP) levels were analyzed as a comparison of myostatin. RESULTS: The data detected cor pulmonale in 39/81 patients, with the mean value of TAPSE of 14.3 mm. Plasma myostatin levels (ng/mL) were significantly higher in patients with cor pulmonale (16.68 ± 2.95) than in those without (13.56 ± 3.09), and much higher than in controls (8.79±2.79), with each p<0.01. Significant differences were also found in plasma BNP levels among the three groups (p<0.05). Multivariate regression analysis suggested that myostatin levels were significantly correlated with the values of TAPSE and RV myocardium performance index among the COPD patients, and that BNP levels were significantly correlated only with systolic pulmonary arterial pressure, with each p<0.05. CONCLUSIONS: Plasma myostatin levels are increased in COPD patients who have cor pulmonale. Stronger correlations of plasma myostatin levels with echocardiographic indexes of the right heart suggest that myostatin might be superior to BNP in the early diagnosis of cor pulmonale in COPD.


Asunto(s)
Miostatina/sangre , Enfermedad Pulmonar Obstructiva Crónica/sangre , Enfermedad Pulmonar Obstructiva Crónica/complicaciones , Enfermedad Cardiopulmonar/sangre , Enfermedad Cardiopulmonar/etiología , Anciano , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Péptido Natriurético Encefálico/sangre , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico por imagen , Enfermedad Cardiopulmonar/diagnóstico por imagen , Ultrasonografía
7.
Respirology ; 20(7): 1073-81, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26122009

RESUMEN

BACKGROUND AND OBJECTIVE: The triplet of airway infection, inflammation and bronchial wall destruction associated with excessive matrix metalloproteinases (MMP) release and imbalance of tissue inhibitor metalloproteinase-1 (TIMP-1) is implicated in bronchiectasis. We sought to determine the associations between sputum MMP (MMP-8, MMP-9) and TIMP-1 and the severity of bronchiectasis; the utility of MMP in predicting risks of future bronchiectasis exacerbations (BE); and the changes in MMP levels during BE. METHODS: We recruited 102 patients with stable bronchiectasis and 22 healthy subjects. For bronchiectasis patients, baseline measurements consisted of sputum inflammation and MMP measurements, bacterial culture, spirometry and chest high-resolution computed tomography (HRCT). Bronchiectasis patients were followed up for 1 year to determine the frequency of BE. Changes in MMP levels during BE were assessed in 36 bronchiectasis patients. RESULTS: Sputum MMP-8, MMP-9 and MMP-9/TIMP-1 ratio in bronchiectasis patients were significantly increased compared with healthy subjects. MMP-8 and MMP-9 levels, but not TIMP-1, were positively correlated with clinical measures, including HRCT scores, spirometry and Bronchiectasis Severity Index. Seventy-nine bronchiectasis patients were included in survival analyses of BE. Lower levels of baseline MMP-9 were associated with reduced risks of and a longer time to the first BE during follow-up. MMP-8 and MMP-9, but not TIMP-1 or MMP-9/TIMP-1 ratio, were significantly heightened during BE. CONCLUSIONS: Sputum MMP might be useful biomarkers for the assessment of bronchiectasis severity and the prediction of future risks of BE. Our results provide the rationales for the future clinical application of MMP inhibitors.


Asunto(s)
Bronquiectasia , Metaloproteinasa 8 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/metabolismo , Esputo/metabolismo , Inhibidor Tisular de Metaloproteinasa-1/metabolismo , Adulto , Anciano , Biomarcadores/metabolismo , Bronquiectasia/diagnóstico , Bronquiectasia/metabolismo , Bronquiectasia/fisiopatología , China , Estudios Transversales , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Inflamación/metabolismo , Masculino , Persona de Mediana Edad , Pronóstico , Espirometría/métodos , Tomografía Computarizada por Rayos X/métodos
8.
Respir Care ; 60(8): 1180-9, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26060319

RESUMEN

BACKGROUND: Bronchiectasis exacerbations are critical events characterized by worsened symptoms and signs (ie, cough frequency, sputum volume, malaise). OBJECTIVES: Our goal was to examine variations in airway and systemic inflammation, spirometry, and quality of life during steady state, bronchiectasis exacerbations, and convalescence (1 week following a 2-week antibiotic treatment) to determine whether potentially pathogenic microorganisms, including Pseudomonas aeruginosa, were associated with poorer conditions during bronchiectasis exacerbations. METHODS: Peripheral blood and sputum were sampled to detect inflammatory mediators and bacterial densities. Spirometry and quality of life (St George Respiratory Questionnaire [SGRQ]) were assessed during the 3 stages. RESULTS: Forty-eight subjects with bronchiectasis (43.2 ± 14.2 y of age) were analyzed. No notable differences in species and density of potentially pathogenic microorganisms were found during bronchiectasis exacerbations. Except for CXCL8 and tumor necrosis factor alpha (TNF-α), serum inflammation was heightened during bronchiectasis exacerbations and recovered during convalescence. Even though sputum TNF-α was markedly higher during bronchiectasis exacerbations and remained heightened during convalescence, the variations in miscellaneous sputum markers were unremarkable. Bronchiectasis exacerbations were associated with notably higher SGRQ symptom and total scores, which recovered during convalescence. FVC, FEV1, and maximum mid-expiratory flow worsened during bronchiectasis exacerbations (median change from baseline of -2.2%, -0.8%, and -1.3%) and recovered during convalescence (median change from baseline of 0.6%, 0.7%, and -0.7%). Compared with no bacterial isolation, potentially pathogenic microorganism or P. aeruginosa isolation at baseline did not result in poorer clinical condition during bronchiectasis exacerbations. CONCLUSIONS: Bronchiectasis exacerbations are characterized by heightened inflammatory responses and poorer quality of life and spirometry, but not by increased bacterial density, which applies for subjects with and without potentially pathogenic microorganism isolation when clinically stable. (ClinicalTrials.gov registration NCT01761214.).


Asunto(s)
Bronquiectasia/fisiopatología , Progresión de la Enfermedad , Mediadores de Inflamación/sangre , Calidad de Vida , Espirometría/estadística & datos numéricos , Adulto , Biomarcadores/análisis , Biomarcadores/metabolismo , Bronquiectasia/complicaciones , Bronquiectasia/psicología , Convalecencia , Femenino , Volumen Espiratorio Forzado/fisiología , Humanos , Masculino , Persona de Mediana Edad , Pseudomonas aeruginosa/aislamiento & purificación , Esputo/química , Factor de Necrosis Tumoral alfa/análisis
9.
J Thorac Dis ; 7(4): 625-36, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25973228

RESUMEN

BACKGROUND: Current status of Pseudomonas aeruginosa (PA) infection in clinically stable bronchiectasis in mainland China remains unclear. OBJECTIVE: To compare the inflammation and lung function impairment in bronchiectasis patients isolated or infected with PA, potentially pathogenic microorganisms (PPMs) and commensals, and to identify factors associated with PA isolation and infection. METHODS: Patients with steady-state bronchiectasis and healthy subjects were recruited. Peripheral blood and sputum were sampled to determine inflammatory markers and bacterial loads in steady-state bronchiectasis and health. Spirometry and diffusing capacity were also measured. RESULTS: We enrolled 144 bronchiectasis patients and 23 healthy subjects. PA isolation and infection accounted for 44 and 39 patients, who demonstrated significant inflammatory responses and markedly impaired spirometry, but not diffusing capacity, compared with healthy subjects and patients isolated with other PPMs and commensals (all P<0.05). Except for heightened sputum inflammatory responses, there were no notable differences in serum inflammation and lung function as with the increased density of PA. Female gender [odds ratio (OR): 3.10 for PA isolation; OR: 3.74 for PA infection], 4 or more exacerbations within 2 years (OR: 3.74 for PA isolation, OR: 2.95 for PA infection) and cystic bronchiectasis (OR: 3.63 for PA isolation, OR: 4.47 for PA infection) were the factors consistently associated with PA isolation and infection. CONCLUSIONS: PA elicits intense inflammation and lung function impairment in steady-state bronchiectasis. The density of PA does not correlate with most clinical indices. PA infection is associated with females, frequent exacerbations and cystic bronchiectasis.

10.
Respirology ; 20(5): 739-48, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25819403

RESUMEN

BACKGROUND AND OBJECTIVE: Aetiologies of bronchiectasis in mainland China and their comparisons with those in western countries are unknown. We aimed to investigate bronchiectasis aetiologies in Guangzhou, southern China, and to determine ethnic or geographic differences with reports from western countries. METHODS: Consecutive patients with steady-state bronchiectasis were randomly recruited. Past history was meticulously extracted. Patients underwent physical examination, saccharine test, humoral immunity assays, gastroesophageal reflux scoring and sputum culture. Fiberoptic bronchoscopy, total immunoglobin E (IgE) and Aspergillus fumigatus-specific IgE measurement, 24-h gastroesophageal pH monitoring and miscellaneous screening tests were performed, if indicated. This entailed comparisons on aetiologies with literature reports. RESULTS: We enrolled 148 patients (44.6 ± 13.8 years, 92 females), most of whom had mild to moderate bronchiectasis. Idiopathic (46.0%), post-infectious (27.0%) and immunodeficiency (8.8%) were the most common aetiologies. Miscellaneous aetiologies consisted of asthma (5.4%), gastroesophageal reflux (4.1%), aspergillosis (2.7%), congenital lung malformation (2.0%), Kartagener syndrome (1.4%), rheumatoid arthritis (1.4%), chronic obstructive pulmonary disease (0.7%), Young's syndrome (0.7%), yellow nail's syndrome (0.7%), eosinophilic bronchiolitis (0.7%) and foreign bodies (0.7%). No notable differences in clinical characteristics between idiopathic and known aetiologies were found. Ethnic or geographic variations of aetiologies were overall unremarkable. CONCLUSIONS: Idiopathic, post-infectious and immunodeficiency constitute major bronchiectasis aetiologies in Guangzhou. Clinical characteristics of patients between known aetiologies and idiopathic bronchiectasis were similar. Ethnicity and geography only account for limited differences in aetiologic spectra. These findings will offer rationales for early diagnosis and management of bronchiectasis in future studies and clinical practice in China.


Asunto(s)
Bronquiectasia , Adulto , Aspergillus fumigatus/inmunología , Aspergillus fumigatus/aislamiento & purificación , Asma/complicaciones , Bronquiectasia/diagnóstico , Bronquiectasia/etnología , Bronquiectasia/etiología , Bronquiectasia/fisiopatología , China/epidemiología , Demografía , Etnicidad , Femenino , Reflujo Gastroesofágico/complicaciones , Humanos , Síndromes de Inmunodeficiencia , Síndrome de Kartagener/complicaciones , Masculino , Persona de Mediana Edad , Oligospermia , Enfermedad Pulmonar Obstructiva Crónica/complicaciones , Infecciones del Sistema Respiratorio , Índice de Severidad de la Enfermedad , Tomografía Computarizada por Rayos X , Síndrome de la Uña Amarilla/complicaciones
11.
Curr Med Res Opin ; 31(4): 843-52, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25708564

RESUMEN

BACKGROUND: The profiles of 6-minute walk distance (6MWD) in adults with clinically stable bronchiectasis in Chinese adult patients with bronchiectasis are unclear. OBJECTIVES: To delineate the 6MWD by stratification of clinical indices, and to investigate the factors associated with reduced 6MWD in Chinese adults with clinically stable bronchiectasis. METHODS: We recruited 141 adult bronchiectasis patients (mean age: 44.3 ± 13.9 years). Demography, radiology, spirometry, diffusing capacity, etiology, sputum bacteriology, modified Medical Research Council dyspnea scale (MMRC) and quality of life were assessed. The safety profile of the measurement was also examined. RESULTS: Lower levels of 6MWD were associated with older age (>50 years), higher HRCT total score, presence of cystic bronchiectasis, bilateral bronchiectasis, reduced diffusing capacity, higher MMRC score, and higher SGRQ scores. Correlation coefficients between 6MWD and spirometry and quality of life scores were different in patients with 6MWD higher and lower than lower limit of normal. DLCO being less than 80% predicted (OR = 3.13, 95% CI: 1.32-7.43, P = 0.01) and MMRC scale between 1 and 4 (OR = 6.42, 95% CI: 2.27-18.18, P < 0.01) were the factors associated with 6MWD being less than the lower limit of normal (80% predicted value). No severe adverse events were reported. CONCLUSION: The 6MWD could be safely measured in adult patients with bronchiectasis and is poorly associated with clinical parameters. DLCO less than 80% predicted and higher MMRC scale are independent predictors of 6MWD below the lower limit of normal. Our findings will provide a reference for management of bronchiectasis patients in mainland China.


Asunto(s)
Bronquiectasia/fisiopatología , Prueba de Esfuerzo/métodos , Calidad de Vida , Caminata/fisiología , Adulto , Pueblo Asiatico , China , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Espirometría
12.
Ann Am Thorac Soc ; 12(5): 657-65, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25654540

RESUMEN

RATIONALE: The usefulness of impulse oscillometry (IOS) in bronchiectasis has not been systematically investigated. OBJECTIVES: To determine the usefulness of IOS parameters and their correlation with radiology, disease severity, sputum bacteriology, and spirometry, and to compare the changes in IOS parameters during exacerbations and convalescence of bronchiectasis. METHODS: We recruited 100 patients with bronchiectasis and 28 healthy subjects. Receiver operating characteristic curve was plotted to analyze the diagnostic performance of IOS parameters. Chest high-resolution computed tomography (HRCT), Bronchiectasis Severity Index (BSI) assessment, sputum culture, and spirometry were performed. Correlation between IOS parameters and clinical indices was determined using the Spearman model. Changes in IOS parameters, compared with spirometry, during exacerbation were assessed in 16 patients with bronchiectasis. MEASUREMENTS AND MAIN RESULTS: IOS parameters (in particular, resonant frequency) could discriminate patients with bronchiectasis from healthy subjects. Higher levels of IOS parameters were associated with Pseudomonas aeruginosa infection, dyshomogeneity, higher BSI and HRCT score, more bronchiectatic lobes, and cystic bronchiectasis (all P < 0.05). All IOS parameters but lung resistance at 5 Hz were positively correlated with the duration of bronchiectasis symptoms, number of bronchiectatic lobes, HRCT total scores, and BSI (all P < 0.05), but not sputum bacterial density (P > 0.05). IOS parameters, but not spirometric parameters, were not statistically different between peripheral and peripheral plus central segment bronchiectasis (all P > 0.05). Increased frequency dependence (higher resonance frequency or reactance area) was more likely to be associated with lower HRCT scores (≤5) than FEV1. Compared with FEV1, any single IOS parameter being abnormal was more common in mild bronchiectasis, particularly in patients with HRCT score of 5 or lower. IOS parameters were not statistically different from baseline to exacerbations and convalescence (all P > 0.05). CONCLUSIONS: IOS parameters correlate with clinical indices and could reflect peripheral airway abnormality. An increased number of aberrant IOS parameters signals poorer clinical conditions. Increased frequency dependence might be a sensitive marker of mild bronchiectasis. Any single IOS parameter being abnormal sensitively reflects mild bronchiectasis. IOS parameters do not change significantly during bronchiectasis exacerbations. Clinical Trial registered with www.clinicaltrials.gov (NCT01761214).


Asunto(s)
Bronquiectasia/diagnóstico , Volumen Espiratorio Forzado/fisiología , Oscilometría/métodos , Adolescente , Adulto , Anciano , Bronquiectasia/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Curva ROC , Estudios Retrospectivos , Tomografía Computarizada por Rayos X , Adulto Joven
13.
Chest ; 147(6): 1635-1643, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25412225

RESUMEN

BACKGROUND: Although viral infections are a major cause of exacerbations in patients with chronic airway diseases, their roles in triggering bronchiectasis exacerbations in adults remain unclear. Therefore, we prospectively investigated the incidence and clinical impacts of viral infection in adults with bronchiectasis exacerbations. METHODS: The study cohort of 119 adults with bronchiectasis was followed up prospectively for 12 months. Nasopharyngeal swabs and sputum samples were assayed for 16 respiratory viruses, using polymerase chain reaction assays. Symptoms, spirometry, quality of life, bacterial cultures, and inflammatory markers were assessed during steady-state bronchiectasis and exacerbations. RESULTS: A total of 100 exacerbations were captured from 58 patients during 1-year follow-up. Respiratory viruses were found more frequently in nasopharyngeal swabs and sputum during bronchiectasis exacerbations (49 of 100, 49.0%) than during steady state (11 of 58, 18.9%; P < .001). The most common viruses found in patients experiencing exacerbations were coronavirus (19 of 65, 39.2%), rhinovirus (16 of 65, 24.6%), and influenza A/B viruses (16 of 65, 24.6%). Virus-positive exacerbations were associated with a greater increase in markers of systemic and airway inflammation (serum IL-6 and tumor necrosis factor-α; sputum IL-1ß and tumor necrosis factor-α) compared with virus-negative exacerbations, but the differences in spirometric indexes, quality of life, and bacterial density were unremarkable. In receiver operating characteristics analysis, serum interferon-γ-induced protein 10 yielded an area under curve of 0.67 (95% CI, 0.53-0.77; P = .018). Furthermore, a greater proportion of patients with virus-positive exacerbations received IV antibiotics. CONCLUSIONS: Prevalence of viral infections, detected by polymerase chain reaction assay, is higher in cases of bronchiectasis exacerbations than in steady-state bronchiectasis, suggesting that respiratory viruses play crucial roles in triggering bronchiectasis exacerbations. The potential mechanisms of virus-induced bronchiectasis exacerbations merit further investigations. TRIAL REGISTRY: ClinicalTrials.gov; No.: NCT01801657; www.clinicaltrials.gov.


Asunto(s)
Bronquiectasia/fisiopatología , Bronquiectasia/virología , Pulmón/fisiopatología , Pulmón/virología , Virosis/complicaciones , Adolescente , Adulto , Biomarcadores/sangre , Bronquiectasia/sangre , Quimiocina CXCL10/sangre , Femenino , Estudios de Seguimiento , Humanos , Masculino , Valor Predictivo de las Pruebas , Prevalencia , Estudios Prospectivos , Calidad de Vida , Espirometría , Esputo/virología , Virosis/diagnóstico , Virosis/epidemiología , Adulto Joven
14.
PLoS One ; 9(11): e113373, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25405614

RESUMEN

BACKGROUND: Characteristics of lung function impairment in bronchiectasis is not fully understood. OBJECTIVES: To determine the factors associated with lung function impairment and to compare changes in spirometry during bronchiectasis exacerbation and convalescence (1 week following 14-day antibiotic therapy). METHODS: We recruited 142 patients with steady-state bronchiectasis, of whom 44 with acute exacerbations in the follow-up were included in subgroup analyses. Baseline measurements consisted of chest high-resolution computed tomography (HRCT), sputum volume, purulence and bacteriology, spirometry and diffusing capacity. Spirometry, but not diffusing capacity, was examined during acute exacerbations and convalescence. RESULTS: In the final multivariate models, having bronchiectasis symptoms for 10 years or greater (OR = 4.75, 95%CI: 1.46-15.43, P = 0.01), sputum culture positive for Pseudomonas aeruginosa (OR = 4.93, 95%CI: 1.52-15.94, P<0.01) and HRCT total score being 12 or greater (OR = 7.77, 95%CI: 3.21-18.79, P<0.01) were the major variables associated with FEV1 being 50%pred or less; and the only variable associated with reduced DLCO was 4 or more bronchiectatic lobes (OR = 5.91, 95%CI: 2.20-17.23, P<0.01). Overall differences in FVC and FEV1 during exacerbations and convalescence were significant (P<0.05), whereas changes in other spirometric parameters were less notable. This applied even when stratified by the magnitude of FEV1 and DLCO reduction at baseline. CONCLUSION: Significant lung function impairment should raise alert of chest HRCT abnormality and sputum culture positive for Pseudomonas aeruginosa, in patients with predominantly mild to moderate steady-state bronchiectasis. Acute exacerbations elicited reductions in FVC and FEV1. Changes of other spirometric parameters were less significant during exacerbations. TRIAL REGISTRATION: ClinicalTrials.gov NCT01761214.


Asunto(s)
Antibacterianos/uso terapéutico , Bronquiectasia/tratamiento farmacológico , Pulmón/efectos de los fármacos , Esputo/microbiología , Adulto , Bacterias/clasificación , Bacterias/aislamiento & purificación , Carga Bacteriana , Bronquiectasia/fisiopatología , Estudios Transversales , Quimioterapia Combinada , Femenino , Volumen Espiratorio Forzado , Humanos , Pulmón/fisiopatología , Masculino , Persona de Mediana Edad , Análisis Multivariante , Estudios Prospectivos , Pseudomonas aeruginosa/aislamiento & purificación , Pruebas de Función Respiratoria , Espirometría , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
15.
PLoS One ; 9(11): e113057, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25409316

RESUMEN

BACKGROUND: Cough hypersensitivity has been common among respiratory diseases. OBJECTIVE: To determine associations of capsaicin cough sensitivity and clinical parameters in adults with clinically stable bronchiectasis. METHODS: We recruited 135 consecutive adult bronchiectasis patients and 22 healthy subjects. History inquiry, sputum culture, spirometry, chest high-resolution computed tomography (HRCT), Leicester Cough Questionnaire scoring, Bronchiectasis Severity Index (BSI) assessment and capsaicin inhalation challenge were performed. Cough sensitivity was measured as the capsaicin concentration eliciting at least 2 (C2) and 5 coughs (C5). RESULTS: Despite significant overlap between healthy subjects and bronchiectasis patients, both C2 and C5 were significantly lower in the latter group (all P<0.01). Lower levels of C5 were associated with a longer duration of bronchiectasis symptoms, worse HRCT score, higher 24-hour sputum volume, BSI and sputum purulence score, and sputum culture positive for P. aeruginosa. Determinants associated with increased capsaicin cough sensitivity, defined as C5 being 62.5 µmol/L or less, encompassed female gender (OR: 3.25, 95%CI: 1.35-7.83, P<0.01), HRCT total score between 7-12 (OR: 2.57, 95%CI: 1.07-6.173, P = 0.04), BSI between 5-8 (OR: 4.05, 95%CI: 1.48-11.06, P<0.01) and 9 or greater (OR: 4.38, 95%CI: 1.48-12.93, P<0.01). CONCLUSION: Capsaicin cough sensitivity is heightened in a subgroup of bronchiectasis patients and associated with the disease severity. Gender and disease severity, but not sputum purulence, are independent determinants of heightened capsaicin cough sensitivity. Current testing for cough sensitivity diagnosis may be limited because of overlap with healthy subjects but might provide an objective index for assessment of cough in future clinical trials.


Asunto(s)
Bronquiectasia/patología , Capsaicina , Tos/inducido químicamente , Administración por Inhalación , Adulto , Anciano , Bronquiectasia/complicaciones , Bronquiectasia/diagnóstico , Bronquiectasia/microbiología , Estudios Transversales , Femenino , Volumen Espiratorio Forzado/efectos de los fármacos , Humanos , Masculino , Persona de Mediana Edad , Calidad de Vida , Adulto Joven
16.
PLoS One ; 9(7): e102970, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25036723

RESUMEN

BACKGROUND: Sleep disturbances are common in patients with chronic lung diseases, but little is known about the prevalence in patients with bronchiectasis. A cross sectional study was conducted to investigate the prevalence and determinants associated with sleep disturbances, and the correlation between sleep disturbances and quality of life (QoL) in adults with steady-state bronchiectasis. METHODS: One hundred and forty-four bronchiectasis patients and eighty healthy subjects were enrolled. Sleep disturbances, daytime sleepiness, and QoL were measured by utilizing the Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS) and St. George Respiratory Questionnaire (SGRQ), respectively. Demographic, clinical indices, radiology, spirometry, bacteriology, anxiety and depression were also assessed. RESULTS: Adults with steady-state bronchiectasis had a higher prevalence of sleep disturbances (PSQI>5) (57% vs. 29%, P<0.001), but not daytime sleepiness (ESS≥10) (32% vs. 30%, P = 0.76), compared with healthy subjects. In the multivariate model, determinants associated with sleep disturbances in bronchiectasis patients included depression (OR, 10.09; 95% CI, 3.46-29.37; P<0.001), nocturnal cough (OR, 1.89; 95% CI, 1.13-3.18; P = 0.016), aging (OR, 1.04; 95% CI, 1.01-1.07; P = 0.009) and increased 24-hour sputum volume (OR, 2.01; 95% CI, 1.22-3.33; P = 0.006). Patients with sleep disturbances had more significantly impaired QoL affecting all domains than those without. Only 6.2% of patients reported using a sleep medication at least weekly. CONCLUSIONS: In adults with steady-state bronchiectasis, sleep disturbances are more common than in healthy subjects and are related to poorer QoL. Determinants associated with sleep disturbances include depression, aging, nighttime cough and increased sputum volume. Assessment and intervention of sleep disturbances are warranted and may improve QoL.


Asunto(s)
Bronquiectasia/fisiopatología , Trastornos del Sueño-Vigilia/fisiopatología , Sueño/fisiología , Adulto , Estudios de Casos y Controles , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Calidad de Vida , Fases del Sueño/fisiología
17.
PLoS One ; 9(3): e90047, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24603554

RESUMEN

BACKGROUND: A systematic review and meta-analysis was conducted to evaluate the efficacy and safety of macrolide therapy in adults and children with bronchiectasis. METHODS: We searched the PUBMED, EMBASE, CENTRAL databases to identify relevant studies. Two reviewers evaluated the studies and extracted data independently. The primary outcome was the number of bronchiectasis exacerbations. Secondary outcomes included exacerbation-related admissions, quality of life (QoL), spirometry, 6-minute walk test (6MWT) and adverse events. RESULTS: Nine eligible trials with 559 participants were included. Six were conducted on adults, and the remaining on children. Macrolide therapy significantly reduced the number of patients experiencing one or more exacerbation in adults [risk ratio (RR) = 0.59; 95% CI, 0.40 to 0.86; P = 0.006; I2 = 65%] and children [RR = 0.86; 95% CI, 0.75-0.99; P = 0.04; I2 = 0%], but not the number of patients with admissions for exacerbation. Macrolide therapy was also associated with reduced frequency of exacerbations in adults (RR = 0.42; 95% CI, 0.29 to 0.61; P<0.001; I2 = 64%) and children (RR = 0.50; 95% CI, 0.35 to 0.71; P<0.001). Pooled analyses suggested that spirometry, including FEV1 and FVC, were significantly improved in adults but not in children. Macrolide therapy improved the QoL (WMD, -6.56; 95% CI, -11.99 to -1.12; P = 0.02; I2 = 86%) but no significant difference in 6MWT (WMD, 4.15; 95% CI, -11.83 to 20.13; P = 0.61; I2 = 31%) and the overall adverse events (RR, 0.96; 95% CI, 0.82 to 1.13; P = 0.66; I2 = 0%) in adults. However, reports of diarrhea and abdominal discomforts were higher with macrolide therapy. CONCLUSIONS: Macrolide maintenance therapy, both in adults and children, was effective and safe in reducing bronchiectasis exacerbations, but not the admissions for exacerbations. In addition, macrolide administration in adults was associated with improvement in QoL and spirometry, but not 6WMT. Future studies are warranted to verify the optimal populations and clarify its potential effects on antimicrobial resistance.


Asunto(s)
Bronquiectasia/tratamiento farmacológico , Bronquiectasia/fisiopatología , Macrólidos/uso terapéutico , Adulto , Niño , Diarrea/inducido químicamente , Humanos , Macrólidos/efectos adversos , Calidad de Vida , Ensayos Clínicos Controlados Aleatorios como Asunto , Pruebas de Función Respiratoria , Resultado del Tratamiento
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