Developing a Novel Read-Across Concept for Ecotoxicological Risk Assessment of Phosphate Chemicals: A Case Study.

This study introduces a novel concept approach for a read-across assessment, considering species sensitivity differences among phosphate chemicals within structurally similar compound groups. Twenty-five organic chemicals, with a log Kow of 5 or less, were categorized into three functional groups based on acetylcholinesterase (AChE) inhibition as a specific mode of action (MOA). The short-term aquatic toxicity data (LC50) for fish, crustaceans, and insects were collected from the U.S. EPA Ecotoxicology (ECOTOX) Knowledgebase. A geometric mean calculation method was applied for multiple toxic endpoints. Performance metrics for the new read-across concept, including correlation coefficient, bias, precision, and accuracy, were calculated. Overall, a slightly higher overestimation (49.2%) than underestimation (48.4%) in toxicity predictions was observed in two case studies. In Case study I, a strong positive correlation (r = 0.93) between the predicted and known toxicity values of target chemicals was observed, while in Case study II, with limited information on species and their ecotoxicity, showed a moderate correlation (r = 0.75). Overall, the bias and precision for Case study I were 0.32 ± 0.01, while Case study II showed 0.65 ± 0.06; however, the relative bias (%) increased from 37.65% (Case study I) to 91.94% (Case study II). Bland-Altman plots highlight the mean differences of 1.33 (Case study I) and 1.24 (Case study II), respectively. The new read-across concept, focusing on AChE inhibition and structural similarity, demonstrated good reliability, applicability, and accuracy with minimal bias. Future studies are needed to evaluate various types of chemical substances, diverse modes of action, functional groups, toxic endpoints, and test species to ensure overall comprehensiveness and robustness in toxicity predictions.

Association of exposure to indoor molds and dampness with allergic diseases at water-damaged dwellings in Korea.

This study aims to characterize levels of molds, bacteria, and environmental pollutants, identify the associations between indoor mold and dampness exposures and childhood allergic diseases, including asthma, allergic rhinitis, atopic dermatitis, using three different exposure assessment tools. A total of 50 children with their parents who registered in Seoul and Gyeonggi-do in Korea participated in this study. We collated the information on demographic and housing characteristics, environmental conditions, and lifestyle factors using the Korean version of the International Study of Asthma and Allergies in Childhood questionnaire. We also collected environmental monitoring samples of airborne molds and bacteria, total volatile organic compounds, formaldehyde, and particulate matter less than 10 µm. We evaluated and determined water damage, hidden dampness, and mold growth in dwellings using an infrared (IR) thermal camera and field inspection. Univariate and multivariate regression analyses were performed to evaluate the associations between prevalent allergic diseases and exposure to indoor mold and dampness. Indoor mold and bacterial levels were related to the presence of water damage in dwellings, and the mean levels of indoor molds (93.4 ± 73.5 CFU/m3) and bacteria (221.5 ± 124.2 CFU/m3) in water-damaged homes were significantly higher than those for molds (82.0 ± 58.7 CFU/m3) and for bacteria (152.7 ± 82.1 CFU/m3) in non-damaged dwellings (p < 0.05). The crude odds ratios (ORs) of atopic dermatitis were associated with < 6th floor (OR = 3.80), and higher indoor mold (OR = 6.42) and bacterial levels (OR = 6.00). The crude ORs of allergic diseases, defined as a group of cases who ever suffered from two out of three allergic diseases, e.g., asthma and allergic rhinitis, and allergic rhinitis were also increased by 3.8 and 9.3 times as large, respectively, with water damage (+) determined by IR camera (p < 0.05). The adjusted OR of allergic rhinitis was significantly elevated by 10.4 times in the water-damaged dwellings after adjusting age, sex, and secondhand smoke. Therefore, a longitudinal study is needed to characterize dominant mold species using DNA/RNA-based sequencing techniques and identify a causal relationship between mold exposure and allergic diseases in the future.

Real-time counting of wheezing events from lung sounds using deep learning algorithms: Implications for disease prediction and early intervention.

This pioneering study aims to revolutionize self-symptom management and telemedicine-based remote monitoring through the development of a real-time wheeze counting algorithm. Leveraging a novel approach that includes the detailed labeling of one breathing cycle into three types: break, normal, and wheeze, this study not only identifies abnormal sounds within each breath but also captures comprehensive data on their location, duration, and relationships within entire respiratory cycles, including atypical patterns. This innovative strategy is based on a combination of a one-dimensional convolutional neural network (1D-CNN) and a long short-term memory (LSTM) network model, enabling real-time analysis of respiratory sounds. Notably, it stands out for its capacity to handle continuous data, distinguishing it from conventional lung sound classification algorithms. The study utilizes a substantial dataset consisting of 535 respiration cycles from diverse sources, including the Child Sim Lung Sound Simulator, the EMTprep Open-Source Database, Clinical Patient Records, and the ICBHI 2017 Challenge Database. Achieving a classification accuracy of 90%, the exceptional result metrics encompass the identification of each breath cycle and simultaneous detection of the abnormal sound, enabling the real-time wheeze counting of all respirations. This innovative wheeze counter holds the promise of revolutionizing research on predicting lung diseases based on long-term breathing patterns and offers applicability in clinical and non-clinical settings for on-the-go detection and remote intervention of exacerbated respiratory symptoms.

Spatial modeling for radon concentrations in subway stations in Seoul, Korea.

This study examined the environmental and geological determinants of radon concentration in subway stations by applying a spatial statistical model to the integrated GIS database. The data were collected for 237 underground subway stations located inside the city of Seoul, South Korea and used for mapping to illustrate the spatial distribution of airborne radon exposure and analysis of potential contribution of station-specific and geological determinants. A Bayesian conditional autoregressive regression (CAR) model was developed to explain the radon concentrations, and the predicted radon surface was generated and visualized to identify hotspot regions where elevated radon exposure is likely to be present in underground settings. The findings include: (1) subway stations located within granite bedrock maintained relatively higher radon concentrations; (2) underground radon emanation is not only controlled by lithology and the associated uranium content of the rocks and soil, but also by structural factors which facilitate easy migration of radon from deeper parts of the earth's crust; (3) radon risks would be elevated if the underground facility is constructed too deep without any control measure; and (4) not only the foundation of an underground facility but also the nature of the soil and rocks in the vicinity helps determine whether or not dangerous levels of radon gas are likely to accumulate inside. This modeling effort is expected to provide guidelines regarding the identification of future station locations with a lower radon risk and the mandatory installation of adequate radon reduction systems for the underground space where people stay or commute for long periods of time.

Mini-laser based submicron aerosol generator for the simple and stable simulation of combustion particulate matter.

Air pollution causes millions of deaths every year. The aerosols, especially airborne nanoparticles generated by combustion, have detrimental effect on health. To protect public health against harmful aerosols, efforts to develop effective air cleaning technology have continued over the past several decades. However, the aerosol generation method used in air cleaning performance tests still rely largely on the traditional methods such as burning cigarettes, paper, and incense. Since the traditional method is inaccurate and unsteady, a more precisely controlled aerosol generation method should be developed. Here, we present a simple and inexpensive aerosol generation method that can easily and consistently produce submicron aerosols through laser ablation. This device constitutes an integrated system with a high-quality mini laser for rapid aerosol generation and a two-axis moving stage for continuous aerosol generation. We demonstrate that the concentration of generated aerosols could be easily controlled by selecting the laser irradiation time and power, resulting in the generation of ~104 particles/cm3 within a few seconds. In addition, the shape and size of generated aerosols can be controlled by changing the target material. This submicron aerosol generation process can be stably maintained for up to 1 h using small-sized (3 cm × 8 cm) affordable and accessible materials, such as wood and leather, highlighting the advantages of this inexpensive and easy-to-use combustion airborne submicron particle generation method.

Vital signal sensing and manipulation of a microscale organ with a multifunctional soft gripper.

Soft grippers that incorporate functional materials are important in the development of mechanically compliant and multifunctional interfaces for both sensing and stimulating soft objects and organisms. In particular, the capability for firm and delicate grasping of soft cells and organs without mechanical damage is essential to identify the condition of and monitor meaningful biosignals from objects. Here, we report a millimeter-scale soft gripper based on a shape memory polymer that enables manipulating a heavy object (payload-to-weight ratio up to 6400) and grasping organisms at the micro/milliscale. The silver nanowires and crack-based strain sensor embedded in this soft gripper enable simultaneous measurement of the temperature and pressure on grasped objects and offer temperature and mechanical stimuli for the grasped object. We validate our miniaturized soft gripper by demonstrating that it can grasp a snail egg while simultaneously applying a moderate temperature stimulation to induce hatching process and monitor the heart rate of a newborn snail. The results present the potential for widespread utility of soft grippers in the area of biomedical engineering, especially in the development of conditional or closed-loop interfacing with microscale biotissues and organisms.

Five Year Trends of Particulate Matter Concentrations in Korean Regions (2015-2019): When to Ventilate?

Indoor air quality becomes more critical as people stay indoors longer, particularly children and the elderly who are vulnerable to air pollution. Natural ventilation has been recognized as the most economical and effective means of improving indoor air quality, but its benefit is questionable when the external air quality is unacceptable. Such risk-risk tradeoffs would require evidence-based guidelines for households and policymakers, but there is a lack of research that examines spatiotemporal long-term air quality trends, leaving us unclear on when to ventilate. This study aims to suggest the appropriate time for ventilation by analyzing the hourly and quarterly concentrations of particulate matter (PM)10 and PM2.5 in seven metropolitan cities and Jeju island in South Korea from January 2015 to September 2019. Both areas' PM levels decreased until 2018 and rebounded in 2019 but are consistently higher in spring and winter. Overall, the average concentrations of PM10 and PM2.5 peaked in the morning, declined in the afternoon, and rebounded in the evening, but the second peak was more pronounced for PM2.5. This study may suggest ventilation in the afternoon (2-6pm) instead of the morning or late evening, but substantial differences across the regions by season encourage intervention strategies tailored to regional characteristics.

Crowdsourced Mapping for Healthy Food Accessibility in Dallas, Texas: A Feasibility Study.

Since its first use for describing a neighborhood lacking access to food in the 1990's, "food deserts" has been widely addressed by researchers and adopted as an indicator of neighborhood-level food insecurity by governmental agencies, such as USDA. However, mostly due to cost and difficulty in collecting georeferenced data and characteristics of grocery stores, the USDA Food Access Research Atlas is infrequently released, and considers only income, vehicle ownership, and distance to the nearest grocery store. In this paper, we explored the feasibility of a crowdsourced geospatial data source, coupled with additional measures, in supplementing the USDA's current designation of food deserts. We used Yelp data to map food deserts in the city of Dallas and compared them with those based on the 2015 USDA food retailer database. Although direct comparison was not possible due to time mismatch between the two data sources, the discrepancies highlighted the need of a more frequent identification of food deserts for timely policy intervention. Furthermore, we extended mapping to reveal other potential areas of concerns, by adding the Transit Score metric and Yelp's price descriptor of businesses. The resulting maps illustrated the areas with grocery stores nearby but with limited accessibility due to lack of public transit or potential financial barriers in purchasing foods due to high prices. Our findings demonstrate the current status and future potential of up-to-date crowdsourced, georeferenced data as a complement of official government data, which could serve to extend food access research and guide health policies.

Source country-specific burden on health due to high concentrations of PM2.5.

Asian countries face frequent spikes in concentrations of particulate matter smaller than 2.5 µm (PM2.5), which may consist of domestic emissions, transported pollutants from neighboring countries, and secondary aerosol formation (SAF). We aimed to estimate the burden on health in South Korea due to PM2.5 exposure from source countries. We computed the health benefits of meeting air quality guidelines during high pollution periods or spike periods. We used daily mortality counts, PM2.5 concentrations, and primary and secondary contributions to pollutant levels in seven cities and nine provinces in South Korea during 2006-2016. Generalized additive mixed modeling with a Poisson distribution and random effects in 16 regions was used to examine the short-term effects of PM2.5 on mortality. We computed attributable burden due to PM2.5 exposure and the potential benefits of meeting the air quality guidelines set by the World Health Organization (WHO, 25 µg/m3) and the Korea Ministry of Environment (50 and 35 µg/m3 before and after 2015, respectively). A concentration-response curve showed a non-linear relationship between daily mortality counts and PM2.5 levels. The short-term health impacts of PM2.5 were suggested to be 1638 non-accidental deaths in 2016 in South Korea due to daily domestic emissions and pollutants transported from neighboring countries. Of these, 1509, 995, or 238 deaths could have been prevented if the daily mean PM2.5 concentration had been kept below 25, 35, or 50 µg/m3. After accounting for the contribution of SAF to PM2.5, primary sources of PM2.5 resulted in 258-860 and 26-88 deaths due to pollution transported from China and North Korea, respectively, and 162-538 deaths were due to domestic emissions. Meeting the air quality guidelines of the WHO could have prevented most of these deaths.

FEP Encapsulated Crack-Based Sensor for Measurement in Moisture-Laden Environment.

Among many flexible mechanosensors, a crack-based sensor inspired by a spider's slit organ has received considerable attention due to its great sensitivity compared to previous strain sensors. The sensor's limitation, however, lies on its vulnerability to stress concentration and the metal layers' delamination. To address this issue of vulnerability, we used fluorinated ethylene propylene (FEP) as an encapsulation layer on both sides of the sensor. The excellent waterproof and chemical resistance capability of FEP may effectively protect the sensor from damage in water and chemicals while improving the durability against friction.

A Closer Look at the Bivariate Association between Ambient Air Pollution and Allergic Diseases: The Role of Spatial Analysis.

Although previous ecological studies investigating the association between air pollution and allergic diseases accounted for temporal or seasonal relationships, few studies address spatial non-stationarity or autocorrelation explicitly. Our objective was to examine bivariate correlation between outdoor air pollutants and the prevalence of allergic diseases, highlighting the limitation of a non-spatial correlation measure, and suggesting an alternative to address spatial autocorrelation. The 5-year prevalence data (2011⁻2015) of allergic rhinitis, atopic dermatitis, and asthma were integrated with the measures of four major air pollutants (SO2, NO2, CO, and PM10) for each of the 423 sub-districts of Seoul. Lee's L statistics, which captures how much bivariate associations are spatially clustered, was calculated and compared with Pearson's correlation coefficient for each pair of the air pollutants and allergic diseases. A series of maps showing spatiotemporal patterns of allergic diseases at the sub-district level reveals a substantial degree of spatial heterogeneity. A high spatial autocorrelation was observed for all pollutants and diseases, leading to significant dissimilarities between the two bivariate association measures. The local L statistics identifies the areas where a specific air pollutant is considered to be contributing to a type of allergic disease. This study suggests that a bivariate correlation measure between air pollutants and allergic diseases should capture spatially-clustered phenomenon of the association, and detect the local instability in their relationships. It highlights the role of spatial analysis in investigating the contribution of the local-level spatiotemporal dynamics of air pollution to trends and the distribution of allergic diseases.

Association Between Sensitization to Mold and Impaired Pulmonary Function in Children With Asthma.

PURPOSE: Recent data indicate that sensitization to mold contributes to the severity and persistence of asthma. In this study, we investigated the relationships between sensitization to mold and lung function parameters in children with asthma. METHODS: We retrospectively reviewed clinical data from 551 asthmatic subjects. We selected subjects who met clinical diagnostic criteria of asthma. Their spirometry, methacholine challenge tests, and measurements of blood eosinophils, serum IgE, eosinophil cationic protein (ECP) and fractional exhaled nitric oxide (FeNO) results were included. Skin prick testing (SPT) results with 13 common aeroallergens in Korea including house dust mites, animal dander, pollen, cockroach and mold were reviewed. Subjects were divided into 3 groups according to their SPT results. Subjects who showed no positive result to any aeroallergen were designated as group 1 (non-sensitized). Group 2 represented subjects who were sensitized to aeroallergens other than mold (other allergen-sensitized) and group 3 included subjects who were sensitized to mold allergens (mold-sensitized). RESULTS: Among the 551 asthmatic subjects, 67 (12.2%) were sensitized to mold and 366 (66.4%) were sensitized to other aeroallergens. The log mean IgE levels were higher in groups 2 (5.96±1.14 IU/mL) and 3 (5.81±0.97 IU/mL) compared to group 1 (3.88±1.68 IU/mL). Blood eosinophils, ECP and FeNO concentrations were significantly higher in groups 2 and 3, but no significant difference was found between the 2 groups. The mean FEV1 value was significantly lower in group 3 (86.9±12.1%pred) than in groups 2 (92.0±14.8%pred) and 1 (93.4±15.4%pred). The log mean methacholine PC20 was significantly lower in group 3 (0.08±1.91 mg/mL) than in groups 2 (1.31±1.69 mg/mL) and 1 (2.29±1.66 mg/mL). CONCLUSIONS: We observed a differential association between mold and other aeroallergen sensitization, and severity of asthma. Sensitization to mold is associated with lower lung function and increased airway hyper-responsiveness in children with asthma. Mold sensitization could be an important factor determining asthma severity particularly airflow limitation in children.

Comparison of diverse estimation methods for personal exposure to air pollutants and associations with allergic symptoms: The Allergy & Gene-Environment Link (ANGEL) study.

We estimated the exposure to ambient air pollutants and analyzed the associations with allergic diseases. We enrolled 177 children with atopic dermatitis (AD) and 70 asthmatic adults living in Seoul Metropolitan Area, Korea, and followed for 17months between August 2013 and December 2014. Parents or patients recorded symptom scores on a daily basis. Exposure to particulate matter with a diameter <10µm (PM10) and nitrogen dioxide (NO2) was estimated in four different ways in each individual, using the AQ1 (measurements from the nearest air quality monitoring station to residential houses), AQ2 (measurements modified from AQ1 with the indoor level of air pollutants and time activity of each individual), AQ1-DI, and AQ2-DI (measurements modified from AQ1 and AQ2, respectively, with daily inhalation intakes of air pollutants). A generalized linear mixed model (GLMM) was used to analyze the associations between exposure metrics and clinical symptoms after adjusting for ambient temperature and humidity, age, season, gender, and time trend. The exposure metrics for PM10 and NO2 showed different distributions. Symptoms of AD and asthma were positively associated with exposure to PM10, but not NO2, in all exposure metrics. The effect size of PM10 exposure on asthma symptoms was slightly greater in metrics with inhalation capacity (AQ-DIs) than in those without (AQs). This pattern was not observed in AD. Exposure to PM10 is associated with symptom aggravation in childhood AD and adult asthma. Different exposure estimates may be used to evaluate the impact of air pollution on different allergic diseases.

Leptin and Atopic Dermatitis in Korean Elementary School Children.

The prevalence of atopic dermatitis (AD) and obesity have been increasing considerably in Korean school-children. AD is a chronic pruritic recurrent inflammatory skin disorder. Leptin is secreted by adipocytes which has been suggested to be immunologically active; however, their role in AD has not yet been well understood. A total of 227 subjects out of 2,109 elementary school children were defined as having AD based on the ISAAC questionnaire survey. Ninety subjects with AD, aged between 6 and 12 years, completed scoring of severity of AD (SCORAD), skin prick testing, blood tests for total IgE, eosinophil counts, eosinophil cationic protein (ECP) and lipid profiles. Serum leptin levels were also measured. A subject with atopic AD was defined as an AD patient showing at least 1 positive reaction to allergens in skin prick testing. There were no significant differences in age, body mass index, percentage of breast milk feeding, mode of delivery, prevalence of atopy, and lipid profiles between atopic AD and non-atopic AD subjects. The serum leptin levels (log mean±SD) were significantly higher in non-atopic AD group than in the atopic AD group (0.86±0.57 ng/mL vs 0.53±0.72 ng/mL, p=0.045). Subjects with mild-to-moderate AD showed significantly higher serum leptin levels than those with severe AD (0.77±0.67 ng/mL vs 0.33±0.69 ng/mL, p=0.028). There was a marginal inverse correlation between the SCORAD index and the serum leptin concentration in total AD subjects (r=-0.216, p=0.053). The serum leptin levels were significantly higher in non-atopic AD subjects or mild-to-moderate AD subjects. Leptin did not seem to be associated with IgE-mediated inflammation in AD. Obesity-associated high leptin differed between non-atopic AD and atopic AD subjects.

GIS-based Association Between PM10 and Allergic Diseases in Seoul: Implications for Health and Environmental Policy.

PURPOSE: The role of PM10 in the development of allergic diseases remains controversial among epidemiological studies, partly due to the inability to control for spatial variations in large-scale risk factors. This study aims to investigate spatial correspondence between the level of PM10 and allergic diseases at the sub-district level in Seoul, Korea, in order to evaluate whether the impact of PM10 is observable and spatially varies across the subdistricts. METHODS: PM10 measurements at 25 monitoring stations in the city were interpolated to 424 sub-districts where annual inpatient and outpatient count data for 3 types of allergic diseases (atopic dermatitis, asthma, and allergic rhinitis) were collected. We estimated multiple ordinary least square regression models to examine the association of the PM10 level with each of the allergic diseases, controlling for various sub-district level covariates. Geographically weighted regression (GWR) models were conducted to evaluate how the impact of PM10 varies across the sub-districts. RESULTS: PM10 was found to be a significant predictor of atopic dermatitis patient count (P<0.01), with greater association when spatially interpolated at the sub-district level. No significant effect of PM10 was observed on allergic rhinitis and asthma when socioeconomic factors were controlled for. GWR models revealed spatial variation of PM10 effects on atopic dermatitis across the sub-districts in Seoul. The relationship of PM10 levels to atopic dermatitis patient counts is found to be significant only in the Gangbuk region (P<0.01), along with other covariates including average land value, poverty rate, level of education and apartment rate (P<0.01). CONCLUSIONS: Our findings imply that PM10 effects on allergic diseases might not be consistent throughout Seoul. GIS-based spatial modeling techniques could play a role in evaluating spatial variation of air pollution impacts on allergic diseases at the sub-district level, which could provide valuable guidelines for environmental and public health policymakers.

Submicron fungal fragments as another indoor biocontaminant in elementary schools.

There has been great concern about mold in school environments, but few comprehensive assessments of mold have been performed in such settings. Even spore counts or microscopic enumeration only may not be sufficient for evaluating fungal exposure. We explored the levels of submicron fungal fragments with potential heath impact due to their small size in elementary schools and investigated the variation in the concentrations of such particles before and after the rainy season. The concentrations of (1,3)-ß-D-glucan in submicron fungal fragments, airborne mold and bacteria, and PM10 were measured both indoors and outdoors in 70 classrooms at 8 elementary schools from May (before the rainy season) to July (after the rainy season) in 2012. Temperature and relative humidity were also monitored. We compared the levels of submicron fungal fragments among schools before and after the rainy season. The associations of the levels of submicron fungal fragments with other variables were analyzed. Overall, the concentrations of (1,3)-ß-D-glucan ranged from 10 to 347 pg m(-3), and the indoor/outdoor ratios were greater than 1 in every school. After the rainy season, the (1,3)-ß-D-glucan concentrations decreased by about 35%, and similar significant decreases in the concentrations of airborne mold and bacteria and PM10 were observed. This difference was prominent for PM10 (P < 0.001). Only relative humidity was negatively associated with the concentration of submicron fungal fragments (P = 0.007). Our findings confirmed the comparable amounts of submicron fungal fragments in school environments. More comprehensive exposure assessments for smaller-sized fungal particles should be performed for better understanding of their health impact, particularly with regard to seasonal changes.

Infrared camera-proven water-damaged homes are associated with the severity of atopic dermatitis in children.

BACKGROUND: Moisture problems in dwellings have been linked to respiratory symptoms, but little is known about their association with symptoms of atopic dermatitis (AD). Moreover, the questionnaire-based survey or visual inspection for water damage does not use a standardized approach for assessing dampness. OBJECTIVE: To determine water damage in the houses of children with AD by assessing variations in surface temperature with an infrared camera, an interview-led questionnaire, and evaluation of the relation between the presence of water damage and the severity of AD. METHODS: Fifty-two homes of patients with AD were visited, and air samples were obtained from the living room and a child's bedroom. Water damage was determined by thermal assessments using an infrared camera and by the presence of visible mold or water stains. The effect of water damage on the severity of AD was analyzed by comparing the presence or absence of water damage and other aggravating factors between water-damaged and undamaged homes. RESULTS: Water damage was observed in 31 of 52 homes (59.6%), and the concentrations of airborne mold were significantly higher in water-damaged homes than in undamaged homes (P = .0013). However, there was no difference in airborne mold levels between homes with and those without visible mold or water stains. Logistic regression analyses showed that water-damaged homes were significantly related to moderate to severe AD (adjusted odds ratio 14.52, 95% confidence interval 1.75-121.13, P = .0025). CONCLUSION: Water-damaged homes affect the severity of AD in children. Infrared camera-driven assessment is a promising tool for determining moisture problems in buildings.

Exploring Household-level Risk Factors for Self-reported Prevalence of Allergic Diseases Among Low-income Households in Seoul, Korea.

PURPOSE: Indoor risk factors for allergic diseases in low-income households in Korea have been characterized only partially. We evaluated the prevalences of atopic dermatitis, asthma, and allergic rhinitis in Seoul, Korea, to identify key housing and behavioral risk factors of low-income households. METHODS: Statistical analysis of the prevalence of these diseases and various risk factors was conducted using data from a 2010 Ministry of Environment household survey. Logistic regression models were generated using data from 511 low-income household apartments in districts of Seoul. RESULTS: In general, housing factors such as renovation history (P<0.1) and crowding status (P<0.01) were associated with allergic rhinitis, whereas behavioral factors such as frequency of indoor ventilation (P<0.05) and cleaning (P<0.1) were inversely correlated with atopic dermatitis. Indoor smoking was a major trigger of asthma and atopic dermatitis in low-income households (P<0.05). The presence of mold and water leakage in houses were the most important risk factors for all three diseases (P<0.05). CONCLUSIONS: Various risk factors play a role in triggering allergic diseases among low-income households in Seoul, and health or environmental programs mitigating allergic diseases should be tailored to address appropriate housing or behavioral factors in target populations.

Salmonella typhimurium with γ-radiation induced H2AX phosphorylation and apoptosis in melanoma.

To investigate the combinatorial effects using Salmonella and γ-radiation, the Salmonella typhimurium infection in combination with γ-radiation was investigated on melanoma. We showed that ROS expression and H2AX phosphorylation increased during stress by γ-radiation irrespective of Salmonella infection, inducing apoptosis by caspase-3 and bcl2 in tumor cells. In addition, tumor growth was suppressed by this combinatory therapy suggesting candidates for radiation therapy against melanoma.

Development and evaluation of antimicrobial activated carbon fiber filters using Sophora flavescens nanoparticles.

Activated carbon fiber (ACF) filters have a wide range of applications, including air purification, dehumidification, and water purification, due to their large specific surface area, high adsorption capacity and rate, and specific surface reactivity. However, when airborne microorganisms such as bacteria and fungi adhere to the carbon substrate, ACF filters can become a source of microbial contamination, and their filter efficacy declines. Antimicrobial treatments are a promising means of preventing ACF bio-contamination. In this study, we demonstrate the use of Sophora flavescens in antimicrobial nanoparticles coated onto ACF filters. The particles were prepared using an aerosol process consisting of nebulization-thermal drying and particle deposition. The extract from S. flavescens is an effective, natural antimicrobial agent that exhibits antibacterial activity against various pathogens. The efficiency of Staphylococcus epidermidis inactivation increased with the concentration of S. flavescens nanoparticles in the ACF filter coating. The gas adsorption efficiency of the coated antimicrobial ACF filters was also evaluated using toluene. The toluene-removal capacity of the ACF filters remained unchanged while the antimicrobial activity was over 90% for some nanoparticle concentrations. Our results provide a scientific basis for controlling both bioaerosol and gaseous pollutants using antimicrobial ACF filters coated with S. flavescens nanoparticles.