No abstract

In this study, variations of particulate matter (PM) concentrations in subway trains following installation of platform screen doors (PSDs) in the Seoul subway system were investigated. PM samples were collected in the trains on subway lines 1-8 before and after installation of PSDs. It was found that the mean PM 10 concentration in the trains after PSDs installation increased significantly by 29.9% compared to that before installation. In particular, the increase of PM 10 in line 6 was the highest at 103%. When the relationship between PM 10 and PM 2.5 was compared, coefficients of determination (r 2 ) before and after PSDs installations were 0.696 and 0.169, respectively. This suggests that air mixing between the platform and the tunnel after PSDs installation was extremely restricted. In addition, the indoor/outdoor PM 10 ratio following PSDs installation increased from 1.32 to 2.97 relative to the period with no installed PSDs. Furthermore, this study revealed that PM levels in subway trains increased significantly after all underground PSDs were put in use. Several potential factors were examined that could result in this PM increase, such as train ventilation systems, operational conditions, passenger volume, subway depth, and the length of underground segments.Implications: PM 10 concentrations inside the subway trains increased after PSDs installation. This indicates that air quality in trains was very seriously impacted by PSDs. PM 10 levels were also influenced by the tunnel depth and length of the underground segments. To prevent the adverse effect on human health by PM 10 emitted from the tunnel, an applicable ventilation system to reduce PM 10 is required inside trains and tunnels.

The proinflammatory cytokine TNF-α is highly expressed in patients with acute myeloid leukemia (AML) and has been demonstrated to induce rapid proliferation of leukemic blasts. Thus suppressing the production of TNF-α is important because TNF-α can auto-regulate own expression through activation of NF-κB and p38 mitogen-activated protein kinase (MAPK). In this study, we focused on the inhibitory effect of IL-32θ on TNF-α production in acute myeloid leukemia. Approximately 38% of patients with AML express endogenous IL-32θ, which is not expressed in healthy individuals. Furthermore, plasma samples were classified into groups with or without IL-32θ; then, we measured proinflammatory cytokine TNF-α, IL-1β, and IL-6 levels. TNF-α production was not increased in patients with IL-32θ expression than that in the no-IL-32θ group. Using an IL-32θ stable expression system in leukemia cell lines, we found that IL-32θ attenuated phorbol 12-myristate 13-acetate (PMA)-induced TNF-α production. IL-32θ inhibited phosphorylation of p38 MAPK, inhibitor of κB (IκB), and nuclear factor κB (NF-κB), which are key positive regulators of TNF-α expression, and inhibited nuclear translocation of NF-κB. Moreover, the presence of IL-32θ attenuated TNF-α promoter activity and the binding of NF-κB with the TNF-α promoter. In addition, IL-32γ-induced TNF-α production has no correlation with inhibition of TNF-α via IL-32θ expression. Thus, IL-32θ may serve as a potent inhibitor of TNF-α in patients with AML.

단국대학교 의과대학 임상병리학과,2 단국대학교 보건과학대학 임상병리학과 C-reactive protein (CRP) levels are not generally associated with viral infections. This study investigated the changes in the CRP level caused by an infection from respiratory virus (RV). Nasopharyngeal samples from hospitalized patients with suspected RV infection were used to measure the CRP levels, virus load, virus-virus co-infection, age, sex, and length of hospital stay (LOS). Abnormal CRP levels were detected in 62.3% (3,608 out of 5,788) of all RV-positive samples. The percentage of patients with abnormal CRP levels tended to increase with age. Furthermore, LOS in patients with abnormal CRP levels was significantly longer than that in patients with normal CRP levels. The frequency of elevated CRP levels differed according to the causative virus and the frequency of abnormal levels increased with age. Moreover, LOS was longer in those with abnormal CRP levels. These data provide important insights into the role of CRP levels in RV infection.

Almost five million citizens a day are using subways as a means of traffic communication in the Seoul metropolitan. As the subway system is typically a closed environment, indoor air pollution problems frequently occurs and passengers complain of mal-health impact. Especially PM 10 is well known as one of the major pollutants in subway indoor environments. The purpose of this study was to compare the indoor air quality in terms of PM 10 and to quantitatively compare its source contributions in a Seoul subway platform before and after installing platform screen doors (PSD).PM 10 samples were collected on the J station platform of Subway Line 7 in Seoul metropolitan area from Jun. 12, 2008 to Jan. 12, 2009. The samples collected on membrane filters using PM 10 mini-volume portable samplers were then analyzed for trace metals and soluble ions. A total of 18 chemical species (Ba, Mn, Cr, Cd, Si, Fe, Ni, Al, Cu, Pb, Ti, Na-, and SO 4 2-) were analyzed by using an ICP-AES and an IC after performing proper pre-treatments of each sample filter. Based on the chemical information, positive matrix factorization (PMF) model was applied to identify the source of particulate matters. PM 10 for the station was characterized by three sources such as ferrous related source, soil and road dust related source, and fine secondary aerosol source. After installing PSD, the average PM 10 concentration was decreased by 20.5% during the study periods. Especially the contribution of the ferrous related source emitted during train service in a tunnel route was decreased from 59.1%