Pulmonary Function and Incident Bronchitis and Asthma in Children: A Community-Based Prospective Cohort Study

BACKGROUND: Previous studies revealed that reduction of airway caliber in infancy might increase the risks for wheezing and asthma. However, the evidence for the predictive effects of pulmonary function on respiratory health in children was still inconsistent. METHODS: We conducted a population-based prospective cohort study among children in 14 Taiwanese communities. There were 3,160 children completed pulmonary function tests in 2007 and follow-up questionnaire in 2009. Poisson regression models were performed to estimate the effect of pulmonary function on the development of bronchitis and asthma. RESULTS: After adjustment for potential confounders, pulmonary function indices consistently showed protective effects on respiratory diseases in children. The incidence rate ratios of bronchitis and asthma were 0.86 (95% CI 0.79-0.95) and 0.91 (95% CI 0.82-0.99) for forced expiratory volume in 1 second (FEV₁). Similar adverse effects of maximal mid-expiratory flow (MMEF) were also observed on bronchitis (RR = 0.73, 95% CI 0.67-0.81) and asthma (RR = 0.85, 95% CI 0.77-0.93). We found significant decreasing trends in categorized FEV₁ (p for trend = 0.02) and categories of MMEF (p for trend = 0.01) for incident bronchitis. Significant modification effects of traffic-related air pollution were noted for FEV₁ and MMEF on bronchitis and also for MMEF on asthma. CONCLUSIONS: Children with high pulmonary function would have lower risks on the development of bronchitis and asthma. The protective effect of high pulmonary function would be modified by traffic-related air pollution exposure

Measurement of the cosmic charged particle rate at sea level in the latitude range 35∘ ÷ 82∘ N with the PolarquEEEst experiment

After its successful campaign of measurements beyond the Polar Arctic Circle, the PolarquEEEst experiment measured the cosmic charged particle rate at sea level in a latitude interval between 35∘ N and 82∘ N. In this paper, these measurements are described and the corresponding results are discussed

Lung Volume, Breathing Pattern and Ventilation Inhomogeneity in Preterm and Term Infants

BACKGROUND: Morphological changes in preterm infants with bronchopulmonary dysplasia (BPD) have functional consequences on lung volume, ventilation inhomogeneity and respiratory mechanics. Although some studies have shown lower lung volumes and increased ventilation inhomogeneity in BPD infants, conflicting results exist possibly due to differences in sedation and measurement techniques. METHODOLOGY/PRINCIPAL FINDINGS: We studied 127 infants with BPD, 58 preterm infants without BPD and 239 healthy term-born infants, at a matched post-conceptional age of 44 weeks during quiet natural sleep according to ATS/ERS standards. Lung function parameters measured were functional residual capacity (FRC) and ventilation inhomogeneity by multiple breath washout as well as tidal breathing parameters. Preterm infants with BPD had only marginally lower FRC (21.4 mL/kg) than preterm infants without BPD (23.4 mL/kg) and term-born infants (22.6 mL/kg), though there was no trend with disease severity. They also showed higher respiratory rates and lower ratios of time to peak expiratory flow and expiratory time (t(PTEF)/t(E)) than healthy preterm and term controls. These changes were related to disease severity. No differences were found for ventilation inhomogeneity. CONCLUSIONS: Our results suggest that preterm infants with BPD have a high capacity to maintain functional lung volume during natural sleep. The alterations in breathing pattern with disease severity may reflect presence of adaptive mechanisms to cope with the disease process

Expression analysis of asthma candidate genes during human and murine lung development

<p>Abstract</p> <p>Background</p> <p>Little is known about the role of most asthma susceptibility genes during human lung development. Genetic determinants for normal lung development are not only important early in life, but also for later lung function.</p> <p>Objective</p> <p>To investigate the role of expression patterns of well-defined asthma susceptibility genes during human and murine lung development. We hypothesized that genes influencing normal airways development would be over-represented by genes associated with asthma.</p> <p>Methods</p> <p>Asthma genes were first identified via comprehensive search of the current literature. Next, we analyzed their expression patterns in the developing human lung during the pseudoglandular (gestational age, 7-16 weeks) and canalicular (17-26 weeks) stages of development, and in the complete developing lung time series of 3 mouse strains: A/J, SW, C57BL6.</p> <p>Results</p> <p>In total, 96 genes with association to asthma in at least two human populations were identified in the literature. Overall, there was no significant over-representation of the asthma genes among genes differentially expressed during lung development, although trends were seen in the human (Odds ratio, OR 1.22, confidence interval, CI 0.90-1.62) and C57BL6 mouse (OR 1.41, CI 0.92-2.11) data. However, differential expression of some asthma genes was consistent in both developing human and murine lung, e.g. <it>NOD1, EDN1, CCL5, RORA </it>and <it>HLA-G</it>. Among the asthma genes identified in genome wide association studies, <it>ROBO1</it>, <it>RORA, HLA-DQB1, IL2RB </it>and <it>PDE10A </it>were differentially expressed during human lung development.</p> <p>Conclusions</p> <p>Our data provide insight about the role of asthma susceptibility genes during lung development and suggest common mechanisms underlying lung morphogenesis and pathogenesis of respiratory diseases.</p

Fetal and infant origins of asthma

Previous studies have suggested that asthma, like other common diseases, has at least part of its origin early in life. Low birth weight has been shown to be associated with increased risks of asthma, chronic obstructive airway disease, and impaired lung function in adults, and increased risks of respiratory symptoms in early childhood. The developmental plasticity hypothesis suggests that the associations between low birth weight and diseases in later life are explained by adaptation mechanisms in fetal life and infancy in response to various adverse exposures. Various pathways leading from adverse fetal and infant exposures to growth adaptations and respiratory health outcomes have been studied, including fetal and early infant growth patterns, maternal smoking and diet, children’s diet, respiratory tract infections and acetaminophen use, and genetic susceptibility. Still, the specific adverse exposures in fetal and early postnatal life leading to respiratory disease in adult life are not yet fully understood. Current studies suggest that both environmental and genetic factors in various periods of life, and their epigenetic mechanisms may underlie the complex associations of low birth weight with respiratory disease in later life. New well-designed epidemiological studies are needed to identify the specific underlying mechanisms. This review is focused on specific adverse fetal and infant growth patterns and exposures, genetic susceptibility, possible respiratory adaptations and perspectives for new studies

High latitude observation of the Forbush decrease during the May 2024 solar storms with muon and neutron detectors on Svalbard

During the series of intense solar flares and coronal mass ejections, that occurred in May 2024, a remarkable Forbush decrease in the cosmic ray flux was observed on the Earth. While this event was observed by particle detectors around the world, the archipelago of Svalbard was heavily exposed to it due to the weak geomagnetic shielding in the polar region. In this study, an analysis of the Forbush decrease event was carried out with a unique combination of muon and neutron detectors on Svalbard: at Ny-Alesund three scintillator-based muon telescopes of the Extreme Energy Events (EEE) project, 14 channels of a Bonner Sphere neutron Spectrometer (BSS), and thermal and epithermal neutron sensors used for hydrological monitoring; and, at Barentsburg, a high-energy neutron monitor operated by the Polar Geophysical Institute. Most sensors showed significant responses and correlation during the event. The observed relative magnitude of the Forbush decrease was found to depend on the detector’s energy sensitivity and was ~9% for thermal neutrons, ~8% for high-energy neutrons, and ~3% for muons. The uncertainty of these results strongly depends on factors like the count rate, which ranged from 10^1 to 10^5 cph and resulted in a low signal-to-noise ratio particularly for the BSS. These multi-particle and multi-energy observations provide an unprecendented view on the Earth’s exposure to cosmic rays during solar events

Cardiac resynchronization therapy when no lateral pacing option exists: vectorcardiographic guided non-lateral left ventricular lead placement predicts acute hemodynamic response

Aims A difficult cardiac resynchronization therapy (CRT) implantation scenario emerges when no lateral pacing option exists. The aim of this study was to explore the effect of biventricular pacing (BIVP) on vectorcardiographic parameters in patients with a non-lateral left ventricular (LV) lead position. We hypothesized that perimeter and area reduction for both the QRS complex and T-wave would predict acute CRT response.Methods and results Twenty-six patients (14 ischaemic) with a mean age of 63 +/- 10 years and standard CRT indication underwent device implantation with continuous LV pressure registration. The LV lead was placed in either an anterior or apical position. Biventricular pacing was performed at a rate 10% above intrinsic rhythm with acute CRT response defined as LV Delta dP/dt(max) &gt;10%. Using this criterion 12 patients were identified as acute CRT responders (responders: 16.7 +/- 4.8% vs. non-responders: 1.9 +/- 5.3%, P&lt;0.001). Vectorcardiographic assessment of the QRS complex and T-wave were performed at baseline and under BIVP. Based on the observed changes in three-dimensional area and perimeter, Delta QRS-area (responders: -46.7 +/- 39.6% vs. non-responders: 1.1 +/- 50.9%, P=0.006) was considered as the preferred parameter. Receiver operating characteristic curve analysis identified -40% as the optimal cut-off value (sensitivity 67% and specificity 93%) for prediction of acute CRT response (AUC = 0.81, P &lt; 0.01). A significant correlation was observed between LV Delta dP/dt(max) and Delta QRS-area (R-2 =0.37, P=0.001).Conclusion Delta QRS-area is correlated to LV Delta dP/dt(max) and predicts acute CRT response in patients with a non-lateral LV lead position. Assessment of Delta QRS-area might be a useful tool for patient specific LV lead placement when no lateral pacing option exists