Air pollution and acute kidney injury with comorbid disease: A nationwide case-crossover study in South Korea.

Emerging evidence suggests that air pollution is a significant contributor to the global burden of kidney disease. Although acute kidney injury (AKI) is a common secondary event in ill patients, evidence regarding the association between air pollution and AKI accompanied by specific comorbidities is limited. This study aimed to estimate the association between short-term exposure to air pollution (fine particulate matter ≤2.5 µm [PM2.5] and ozone [O3]) and incident AKI by comorbid diseases using the Korea National Health Information Database (NHID). Total of 160,390 incident AKI cases, defined as an emergency department (ED) visit due to AKI, were observed within the period 2015-2021 in inland South Korea. A time-stratified case-crossover design was applied for PM2.5 and O3 individually, using a conditional logistic regression model within each case and its own control (three or four days of the same day of the week in the same month) to estimate the association between short-term air pollution exposure and ED visits due to AKI. Short-term exposure to PM2.5 and O3 was associated with ED visits due to AKI with ORs of 1.008 (95% confidence interval [CI]: 0.999, 1.017) and 1.019 (95% CI: 1.005, 1.033) for an interquartile range (IQR) increase in lag 0-1 day PM2.5 and O3 respectively, although OR for PM2.5 was marginally significant. The odds of incident AKI associated with PM2.5 was evident in conjunction with ischemic heart disease, cerebrovascular disease, gastrointestinal bleeding, and pneumonia. For O3, the estimated odds was prominent for AKI with ischemic heart disease. In addition, the comorbid disease-specific odds of AKI attributed to air pollution varied by sex and age. Our findings provide epidemiological evidence of a plausible mechanism between air pollution and incident AKI and suggest the need for personalized AKI prevention strategies attributed to air pollution.

Association of long-term exposure to air pollution with chronic sleep deprivation in South Korea: A community-level longitudinal study, 2008-2018.

BACKGROUND AND OBJECTIVE: Although there are many findings about the effects of fine particulate matter (PM2.5) and sleep deprivation on health respectively, the association between PM2.5 and chronic sleep deprivation has rarely been investigated. Thus, we aimed to investigate this association using a nationwide survey in South Korea. METHOD: We examined the association between long-term exposure to PM2.5 and chronic sleep deprivation using a national cross-sectional health survey covering the entire 226 districts in inland South Korea from 2008 to 2018, with a machine learning-based national air pollution prediction model with 1 km2 spatial resolution. RESULTS: Chronic sleep deprivation was positively associated with PM2.5 in the total population (odds ratio (OR): 1.09, 95% confidence interval (CI): 1.05-1.13) and sub-population (low, middle, high population density areas with OR: 1.127, 1.09, and 1.059, respectively). The association was consistently observed in both sexes (males with OR: 1.09, females with OR: 1.09)) and was more pronounced in the elderly population (OR: 1.12) than in the middle-aged (OR: 1.07) and young (OR: 1.09) populations. CONCLUSIONS: Our results are consistent with the hypothesis regarding the relationship between long-term PM2.5 exposure and chronic sleep deprivation, and the study provides quantitative evidence for public health interventions to improve air quality that can affect chronic sleep conditions.

Near-field sub-diffraction photolithography with an elastomeric photomask.

Photolithography is the prevalent microfabrication technology. It needs to meet resolution and yield demands at a cost that makes it economically viable. However, conventional far-field photolithography has reached the diffraction limit, which imposes complex optics and short-wavelength beam source to achieve high resolution at the expense of cost efficiency. Here, we present a cost-effective near-field optical printing approach that uses metal patterns embedded in a flexible elastomer photomask with mechanical robustness. This technique generates sub-diffraction patterns that are smaller than 1/10th of the wavelength of the incoming light. It can be integrated into existing hardware and standard mercury lamp, and used for a variety of surfaces, such as curved, rough and defect surfaces. This method offers a higher resolution than common light-based printing systems, while enabling parallel-writing. We anticipate that it will be widely used in academic and industrial productions.

Comparative study of Korean White Ginseng and Korean Red Ginseng on efficacies of OVA-induced asthma model in mice.

BACKGROUND: Korean ginseng is a well-known medicinal herb that has been widely used in traditional medicine to treat various diseases, including asthma. Ginseng can be classified as white ginseng (WG) or red ginseng (RG), according to processing conditions. In this study, the authors compared the efficacies of these two ginseng types in a mouse model of acute asthma. METHODS: To produce the acute asthma model, BALB/c mice were sensitized with ovalbumin (OVA) and aluminum hydroxide, and then challenged with OVA. WG and RG extracts were administered to mice orally. The influences of WG and RG on airway hyperresponsiveness (AHR), immune cell distributions in bronchoalveolar lavage fluid (BALF), and OVA-specific immunoglobulin E (IgE), IgG1, and IgG2a in serum were investigated. Cytokine production by lymphocytes isolated from peribronchial lymph nodes and histopathological changes was also examined. RESULTS: In OVA-sensitized mice, both WG and RG reduced AHR and suppressed immune cell infiltration in bronchoalveolar regions. BALF OVA-specific IgE levels were significantly lower in RG-treated OVA-sensitized mice than in the OVA-sensitized control group. WG and RG also suppressed inflammatory cytokine production by peribronchial lymphocytes. Histopathological findings showed reduced inflammatory cell infiltration and airway remodeling (e.g., epithelial hyperplasia) in WG- and RG-treated OVA mice compared with OVA controls. CONCLUSION: In this study, WG and RG showed antiasthmatic effects in an OVA-sensitized mouse model, and the efficacies of RG were found to be better than those of WG.