No abstract

Reactive oxygen species are centrally involved in the pathophysiology of airway diseases such as asthma and chronic obstructive pulmonary disease. This study reports the development of a chemiluminescence assay and a device for measuring hydrogen peroxide in the exhaled breath condensate of asthma patients and healthy participants. A stand-alone photon detection device was constructed for use with an optimized chemiluminescence assay. Calibrations using a catalase control to scavenge residual hydrogen peroxide in calibrant solutions provided analytically sensitive and specific measurements. We evaluated exhaled breath condensate hydrogen peroxide in 60 patients (ages 20-83; 30 healthy patients and 30 asthma patients) recruited from the John Peter Smith Hospital Network. The exhaled breath condensate hydrogen peroxide concentrations trended toward higher values in asthma patients compared to healthy participants (mean 142.5 vs 115.5 nM; p = 0.32). Asthma patients who had not used an albuterol rescue inhaler in the past week were compared to those who had and showed a trend toward higher hydrogen peroxide levels (mean 172.8 vs 115.9 nM; p = 0.25), and these patients also trended toward higher hydrogen peroxide than healthy participants (mean 172.8 vs 115.5 nM; p = 0.14). This pilot study demonstrates the ability of the newly developed assay and device to measure exhaled breath condensate hydrogen peroxide in asthma patients and healthy participants. The trends observed in this study are in agreement with previous literature and warrant further investigation of using this system to measure exhaled breath condensate hydrogen peroxide for monitoring oxidative stress in asthma.

The prevalence of e-cigarette usage has increased in non-smokers and those who are planning to quit smoking since introduced in 2003. Although the potential long term adverse effects have not been studied in humans, there have been studies showing that e-cigarette vapor causes release of proinflammatory cytokines leading to cytotoxic damage to alveolar epithelial cells, increase in the release of fibroblast growth factor (FGF) in the alveolar epithelial cells which leads to fibroblastic proliferation, and increased risk of staphylococcus aureus and viral infections which are implicated in the pathogenesis of diffuse alveolar damage. We describe a case of a 47-year-old woman who was diagnosed with histologically confirmed diffuse alveolar damage (DAD). She had no significant medical history and she had been smoking e-cigarettes for 3 years prior to presentation. This case report describes the potential association between e-cigarettes and diffuse alveolar damage while making reference to relevant associated studies.

In this study, Mexican Americans reported higher rates of sleep disturbances than non-Hispanic whites. Disturbed sleep was positively associated with depression and the factor scores for Dysphoria and Cognitive Impairment in both groups. Given the paucity of research on sleep disorders in Mexican Americans, identifying what sleep disorders are present and the impact treating these sleep disorders have on depression warrant further investigation.