American journal of respiratory and critical care medicine
-
Am. J. Respir. Crit. Care Med. · Oct 2021
Prenatal Ambient Ultrafine Particle Exposure and Childhood Asthma in the Northeastern United States.
Rationale: Ambient ultrafine particles (UFPs; with an aerodynamic diameter < 0.1 μm) may exert greater toxicity than other pollution components because of their enhanced oxidative capacity and ability to translocate systemically. Studies examining associations between prenatal UFP exposure and childhood asthma remain sparse. Objectives: We used daily UFP exposure estimates to identify windows of susceptibility of prenatal UFP exposure related to asthma in children, accounting for sex-specific effects. ⋯ Bayesian distributed lag interaction models indicated sex differences in the windows of susceptibility, with the highest risk of asthma seen in females exposed to higher UFP concentrations during late pregnancy. Conclusions: Prenatal UFP exposure was associated with asthma development in children, independent of correlated ambient NO2 and temperature. Findings will benefit future research and policy-makers who are considering appropriate regulations to reduce the adverse effects of UFPs on child respiratory health.
-
Am. J. Respir. Crit. Care Med. · Oct 2021
Air Pollution, Genetic Factors and the Risk of Lung Cancer: A Prospective Study in the UK Biobank.
Rationale: Both genetic and environmental factors contribute to lung cancer, but the degree to which air pollution modifies the impact of genetic susceptibility on lung cancer remains unknown. Objectives: To investigate whether air pollution and genetic factors jointly contribute to incident lung cancer. Methods: We analyzed data from 455,974 participants (53% women) without previous cancer at baseline in the UK Biobank. ⋯ There were additive interactions between air pollutants and the genetic risk. Compared with participants with low genetic risk and low air pollution exposure, those with high air pollution exposure and high genetic risk had the highest risk of lung cancer (PM2.5: HR, 1.71; 95% CI, 1.45-2.02; PM10: HR, 1.77; 95% CI, 1.50-2.10; NO2: HR, 1.77; 95% CI, 1.42-2.22; NOx: HR, 1.67; 95% CI, 1.43-1.95). Conclusions: Long-term exposure to air pollution may increase the risk of lung cancer, especially in those with high genetic risk.
-
Rationale: New advanced bronchoscopic treatment options for patients with severe chronic obstructive pulmonary disease (COPD) have led to increased interest for COPD phenotyping, including fissure completeness. Objectives: We investigated clinical, environmental, and genetic factors contributing to fissure completeness in patients with and without COPD. Methods: We used data from 9,926 participants of the COPDGene study who underwent chest computed tomographic (CT) scans. ⋯ In African American subjects, rs264866, rs4904145 and rs6504172 were identified as significant associations. Rs2173623, rs6504172, and rs7209556 lead to WNT5A and HOXB antisense RNA expression, which play an important role during embryogenesis. Conclusions: Fissure completeness is genetically determined and not dependent on age, sex, smoking status, the presence and severity of COPD (including exacerbation frequency), maternal smoking during pregnancy, or maternal COPD.
-
Am. J. Respir. Crit. Care Med. · Oct 2021
Observational StudyShear Wave Elastography, A New Tool for Diaphragmatic Qualitative Assessment. A Translational Study.
Rationale: Prolonged mechanical ventilation is often associated with either a decrease (known atrophy) or an increase (supposed injury) in diaphragmatic thickness. Shear wave elastography is a noninvasive technique that measures shear modulus, a surrogate of tissue stiffness and mechanical properties. Objectives: To describe changes in shear modulus (SM) during the ICU stay and the relationship with alterations in muscle thickness. ⋯ In the piglet sample, a decrease in SM over 3 days of mechanical ventilation was associated with loss of force production, slow and fast fiber atrophy, and increased lipid droplets accumulation. Conclusions: Increases in diaphragm thickness during critical illness is associated with decreased tissue stiffness as demonstrated by shear wave ultrasound elastography, consistent with the development of muscle injury and weakness. Clinical trial registered with www.clinicaltrials.gov (NCT03550222).
-
Am. J. Respir. Crit. Care Med. · Oct 2021
Innate-like Gene Expression of Lung-resident Memory CD8+ T-cells During Experimental Human Influenza: A Clinical Study.
Rationale: Suboptimal vaccine immunogenicity and antigenic mismatch, compounded by poor uptake, means that influenza remains a major global disease. T cells recognizing peptides derived from conserved viral proteins could enhance vaccine-induced cross-strain protection. Objectives: To investigate the kinetics, phenotypes, and function of influenza virus-specific CD8+ resident memory T (Trm) cells in the lower airway and infer the molecular pathways associated with their response to infection in vivo. ⋯ However, gene set enrichment analysis of BAL-fluid CD8+ T cells showed primarily innate cell-related pathways and, during infection, included upregulation of innate chemokines (Cxcl1, Cxcl10, and Cxcl16) that were also expressed by CD8+ cells in bronchial tissues. Conclusions: CD8+ Trm cells in the human lung display innate-like gene and protein expression that demonstrates blurred divisions between innate and adaptive immunity. Clinical study registered with www.clinicaltrials.gov (NCT02755948).