MXene-Vitrimer Nanocomposites: Photo-Thermal Repair, Reinforcement, and Conductivity at Low Volume Fractions Through a Percolative Voronoi-Inspired Microstructure.

An innovative process to multifunctional vitrimer nanocomposites with a percolative MXene minor phase is reported, marking a significant advancement in creating stimuli-repairable, reinforced, sustainable, and conductive nanocomposites at diminished loadings. This achievement arises from a Voronoi-inspired biphasic morphological design via a straight-forward three-step process involving ambient-condition precipitation polymerization of micron-sized prepolymer powders, aqueous powder-coating with 2D MXene (TiCT), and melt-pressing of MXene-coated powders into crosslinked films. Due to the formation of MXene-rich boundaries between thiourethane vitrimer domains in a pervasive low-volume fraction conductive network, a low percolation threshold (≈0.

A multiscale ion diffusion framework sheds light on the diffusion-stability-hysteresis nexus in metal halide perovskites.

Stability and current-voltage hysteresis stand as major obstacles to the commercialization of metal halide perovskites. Both phenomena have been associated with ion migration, with anecdotal evidence that stable devices yield low hysteresis. However, the underlying mechanisms of the complex stability-hysteresis link remain elusive.

Sex and the lung: Observations, hypotheses, and future directions.

Sex-related differences in a variety of lung diseases in infants and young children are reviewed, including respiratory distress syndrome, and chronic lung disease of prematurity, lower respiratory tract illnesses and wheezing, asthma, diffuse, and interstitial lung diseases, and cystic fibrosis. Differences in anatomy and physiology, such as airway size, airway muscle bulk, airway reactivity, airway tone, and cough reflexes may explain much of these sex differences. Better understanding of sex-related lung differences could help personalize respiratory treatment.

Prematurity and respiratory outcomes program (PROP): study protocol of a prospective multicenter study of respiratory outcomes of preterm infants in the United States.

Background: With improved survival rates, short- and long-term respiratory complications of premature birth are increasing, adding significantly to financial and health burdens in the United States. In response, in May 2010, the National Institutes of Health (NIH) and the National Heart, Lung, and Blood Institute (NHLBI) funded a 5-year $18.5 million research initiative to ultimately improve strategies for managing the respiratory complications of preterm and low birth weight infants.

Markers of Differential Response to Inhaled Corticosteroid Treatment Among Children with Mild Persistent Asthma.

Background: Inhaled corticosteroids are recommended as first-line therapy for children with mild persistent asthma; however, specific patient characteristics may modify the treatment response.

Objective: Identify demographic, clinical, and atopic characteristics that may modify the inhaled corticosteroid treatment response among children enrolled in the Treating Children to Prevent Exacerbations of Asthma trial.

Methods: Children aged 6 to 18 years with mild persistent asthma were randomized to 44 weeks of combined, daily, rescue, or placebo treatment.

International consensus on (ICON) pediatric asthma.

Asthma is the most common chronic lower respiratory disease in childhood throughout the world. Several guidelines and/or consensus documents are available to support medical decisions on pediatric asthma. Although there is no doubt that the use of common systematic approaches for management can considerably improve outcomes, dissemination and implementation of these are still major challenges.

Daily or intermittent budesonide in preschool children with recurrent wheezing.

Background: Daily inhaled glucocorticoids are recommended for young children at risk for asthma exacerbations, as indicated by a positive value on the modified asthma predictive index (API) and an exacerbation in the preceding year, but concern remains about daily adherence and effects on growth. We compared daily therapy with intermittent therapy.

Methods: We studied 278 children between the ages of 12 and 53 months who had positive values on the modified API, recurrent wheezing episodes, and at least one exacerbation in the previous year but a low degree of impairment.

Most nocturnal asthma symptoms occur outside of exacerbations and associate with morbidity.

Background: Although nocturnal awakenings help categorize asthma severity and control, their clinical significance has not been thoroughly studied.

Objective: We sought to determine the clinical consequences of nocturnal asthma symptoms requiring albuterol (NASRAs) in children with mild-to-moderate persistent asthma outside of periods when oral corticosteroids were used for worsening asthma symptoms.

Methods: Two hundred eighty-five children aged 6 to 14 years with mild-to-moderate persistent asthma were randomized to receive one of 3 controller regimens and completed daily symptom diaries for 48 weeks.

Growth of preschool children at high risk for asthma 2 years after discontinuation of fluticasone.

Background: The effect on linear growth of daily long-term inhaled corticosteroid therapy in preschool-aged children with recurrent wheezing is controversial.

Objective: We sought to determine the effect of daily inhaled corticosteroid given for 2 years on linear growth in preschool children with recurrent wheezing.

Methods: Children aged 2 and 3 years with recurrent wheezing and positive modified Asthma Predictive Index scores were randomized to a 2-year treatment period of chlorofluorocarbon-delivered fluticasone propionate (176 μg/d) or masked placebo delivered through a valved chamber with a mask and then followed for 2 years off study medication.

Use of beclomethasone dipropionate as rescue treatment for children with mild persistent asthma (TREXA): a randomised, double-blind, placebo-controlled trial.

Background: Daily inhaled corticosteroids are an effective treatment for mild persistent asthma, but some children have exacerbations even with good day-to-day control, and many discontinue treatment after becoming asymptomatic. We assessed the effectiveness of an inhaled corticosteroid (beclomethasone dipropionate) used as rescue treatment.

Methods: In this 44-week, randomised, double-blind, placebo-controlled trial we enrolled children and adolescents with mild persistent asthma aged 5-18 years from five clinical centres in the USA.

Cost-effectiveness analysis of fluticasone versus montelukast in children with mild-to-moderate persistent asthma in the Pediatric Asthma Controller Trial.

Background: Cost-effectiveness analyses of asthma controller regimens for adults exist, but similar evaluations exclusively for children are few.

Objective: We sought to compare the cost-effectiveness of 2 commonly used asthma controllers, fluticasone and montelukast, with data from the Pediatric Asthma Controller Trial.

Methods: We compared the cost-effectiveness of low-dose fluticasone with that of montelukast in a randomized, controlled, multicenter clinical trial in children with mild-to-moderate persistent asthma.

Forced expiratory flow between 25% and 75% of vital capacity and FEV1/forced vital capacity ratio in relation to clinical and physiological parameters in asthmatic children with normal FEV1 values.

Background: The assumption that the assessment of forced expiratory flow between 25% and 75% of vital capacity (FEF(25-75)) does not provide additional information in asthmatic children with normal FEV(1) percent predicted has not been adequately tested.

Objective: We sought to determine whether the measurement of FEF(25-75) percent predicted offers advantages over FEV(1) percent predicted and FEV(1)/forced vital capacity (FVC) percent predicted for the evaluation of childhood asthma.

Methods: This is a secondary analysis of data from the Pediatric Asthma Controller Trial and the Characterizing the Response to a Leukotriene Receptor Antagonist and Inhaled Corticosteroid trials.

Step-up therapy for children with uncontrolled asthma receiving inhaled corticosteroids.

Background: For children who have uncontrolled asthma despite the use of low-dose inhaled corticosteroids (ICS), evidence to guide step-up therapy is lacking.

Methods: We randomly assigned 182 children (6 to 17 years of age), who had uncontrolled asthma while receiving 100 microg of fluticasone twice daily, to receive each of three blinded step-up therapies in random order for 16 weeks: 250 microg of fluticasone twice daily (ICS step-up), 100 microg of fluticasone plus 50 microg of a long-acting beta-agonist twice daily (LABA step-up), or 100 microg of fluticasone twice daily plus 5 or 10 mg of a leukotriene-receptor antagonist daily (LTRA step-up). We used a triple-crossover design and a composite of three outcomes (exacerbations, asthma-control days, and the forced expiratory volume in 1 second) to determine whether the frequency of a differential response to the step-up regimens was more than 25%.

Effect of elevated exhaled nitric oxide levels on the risk of respiratory tract illness in preschool-aged children with moderate-to-severe intermittent wheezing.

Background: The fractional concentration of exhaled nitric oxide (FeNO) is a noninvasive marker for airway inflammation but requires further study in preschool-aged children to determine its clinical relevance.

Objective: To determine whether the risk of respiratory tract illnesses (RTIs), disease burden, and atopic features are related to FeNO in preschool-aged children with moderate-to-severe intermittent wheezing.

Methods: We determined FeNO using the off-line tidal breathing technique in 89 children, aged 12 to 59 months, with moderate-to-severe intermittent wheezing.

Relationship between infant weight gain and later asthma.

Like obesity, the prevalence of asthma has increased over the past several decades. Accelerated patterns of infant growth have been associated with obesity and its co-morbidities. We aimed to determine if infant weight gain pattern is associated with asthma development later in childhood.

Signs and symptoms that precede wheezing in children with a pattern of moderate-to-severe intermittent wheezing.

Objectives: To examine parent-reported signs and symptoms as antecedents of wheezing in preschool children with previous moderate to severe wheezing episodes, and to determine the predictive capacity of these symptom patterns for wheezing events.

Study Design: Parents (n = 238) of children age 12 to 59 months with moderate-to-severe intermittent wheezing enrolled in a year-long clinical trial completed surveys that captured signs and symptoms at the start of a respiratory tract illness (RTI). Sensitivity, specificity, negative predictive value, and positive predictive value (PPV) for each symptom leading to wheezing during that RTI were calculated.

Patient characteristics associated with improved outcomes with use of an inhaled corticosteroid in preschool children at risk for asthma.

Background: Maintenance inhaled corticosteroid (ICS) therapy in preschool children with recurrent wheezing at high-risk for development of asthma produces multiple clinical benefits. However, determination of baseline features associated with ICS responsiveness may identify children most likely to benefit from ICS treatment.

Objective: To determine if demographic and atopic features predict response to ICS in preschool children at high risk for asthma.

Phenotypic predictors of long-term response to inhaled corticosteroid and leukotriene modifier therapies in pediatric asthma.

Background: In children with mild-to-moderate persistent asthma, identification of phenotypic predictors to guide selection of a controller regimen is essential.

Objective: We sought to identify phenotypic characteristics having predictive value for the difference in treatment responses between twice-daily fluticasone and once-daily montelukast.

Methods: Data from the Pediatric Asthma Controller Trial were assessed with multivariate analysis.

Impulse oscillometry versus spirometry in a long-term study of controller therapy for pediatric asthma.

Background: Determination of the benefits and limitations of specific physiologic tests has not been well studied in long-term clinical pediatric trials.

Objective: We sought to determine the utility of impulse oscillometry in a long-term comparison of 3 controller regimens in children with persistent asthma.

Methods: Children 6 to 14 years of age with mild-to-moderate persistent asthma were characterized with oscillometry and spirometry before entry into a clinical trial and then serially during 48 weeks of therapy with either an inhaled corticosteroid, a combination inhaled corticosteroid with a long-acting beta-agonist, or a leukotriene receptor antagonist.

Factors associated with asthma exacerbations during a long-term clinical trial of controller medications in children.

Background: Asthma exacerbations are a common cause of critical illness in children.

Objective: To determine factors associated with exacerbations in children with persistent asthma.

Methods: Regression modeling was used to identify historical, phenotypic, treatment, and time-dependent factors associated with the occurrence of exacerbations, defined by need for oral corticosteroids or emergency or hospital care in the 48-week Pediatric Asthma Controller Trial study.

Episodic use of an inhaled corticosteroid or leukotriene receptor antagonist in preschool children with moderate-to-severe intermittent wheezing.

Background: Acute wheezing illnesses in preschoolers require better management strategies to reduce morbidity.

Objectives: We sought to examine the effectiveness of episodic use of an inhaled corticosteroid and a leukotriene receptor antagonist in preschoolers with intermittent wheezing.

Methods: In a randomized, double-blind, placebo-controlled 12-month trial, 238 children aged 12 to 59 months with moderate-to-severe intermittent wheezing received 7 days of either budesonide inhalation suspension (1 mg twice daily), montelukast (4 mg daily), or placebo in addition to albuterol with each identified respiratory tract illness (RTI).

Azithromycin or montelukast as inhaled corticosteroid-sparing agents in moderate-to-severe childhood asthma study.

Background: Clinical trials in children with moderate-to-severe persistent asthma are limited.

Objective: We sought to determine whether azithromycin or montelukast are inhaled corticosteroid sparing.

Methods: The budesonide dose (with salmeterol [50 microg] twice daily) necessary to achieve control was determined in children 6 to 17 years of age with moderate-to-severe persistent asthma.