High time-resolved variations of proteins in PM2.5 during haze pollution periods in Xi'an, China.

Proteinaceous matter is an important component of PM2.5, which can cause adverse health effects and also influence the air quality and climate change. However, there is little attention to high time-resolved variations and potential role of aerosol proteins during haze pollution periods. In this study, PM2.5 samples were first collected by a medium flow sampler in autumn and winter in Xi'an, China. Then three high time-resolved monitoring campaigns during haze pollution periods were conducted to determine the evolving characteristics of total protein concentration and explore the interactive relationship between protein and other chemical compositions. The results showed that the average protein concentration in PM2.5 in Xi'an (5.46 ± 3.32 µg m-3) was higher than those in most cities of China, and varied by seasons and air pollution conditions. In particular, the protein concentration in PM2.5 increased with the increase of air quality index (AQI). The continuous variations of aerosol proteins during the haze pollution periods further showed that PM2.5, atmospheric humidity and long-distance air mass transport exerted the significant impacts on the protein components in aerosols. Based on the present observation, it is suggested that aerosol proteins might affect the generation of secondary aerosols under haze weather conditions. The present results may provide a new possible insight into the variations and the role of aerosol proteinaceous matter during the formation and development of haze pollution.

Diagnostic Significance of BAT in Anaphylaxis to Non-ionic Contrast Media / 法医学杂志

Objective To investigate the diagnostic significance of basophil activation test (B A T) in ana-phylaxis to non-ionic contrast media through testing the content of CD 63, m ast cell-carboxypeptidase A 3 (M C-CPA 3), and term inal com plem ent com plex SC5b-9 of the individuals by testing their levels in the norm al im m une group and the anaphylaxis groups to β-lactam drugs and non-ionic contrast media. Methods The CD 63 expression of basophilic granulocyte in blood w as detected by flow cytom etry. The levels of M C-CPA 3 in blood serum and SC5b-9 in blood plasm a w ere detected by ELISA . Results The CD 63 expression of basophilic granulocyte in blood, the levels of M C-CPA 3 and SC5b-9 of anaphylaxis to non-ionic contrast media and β-lactam drugs w ere significantly higher than that in norm al im m une group (P<0.05). Conclusion There is activation of basophilic granulocytes, m ast cells and com plem ent system in anaphylaxis to non-ionic contrast media. B A Tcan be used to diagnose the anaphylaxis to non-ionic contrast media.