Asian Sand Dust Particles Enhance the Development of Aspergillus fumigatus Biofilm on Nasal Epithelial Cells

Background: Asian sand dust (ASD) and Aspergillus fumigatus are known risk factors for airway mucosal inflammatory diseases. Bacterial and fungal biofilms commonly coexist in chronic rhinosinusitis and fungus balls. We evaluated the effects of ASD on the development of A. fumigatus biofilm formation on nasal epithelial cells. Methods: Primary nasal epithelial cells were cultured with A. fumigatus conidia with or without ASD for 72 h. The production of interleukin (IL)-6, IL-8, and transforming growth factor (TGF)-β1 from nasal epithelial cells was determined by the enzyme-linked immunosorbent assay. The effects of ASD on A. fumigatus biofilm formation were determined using crystal violet, concanavalin A, safranin staining, and confocal scanning laser microscopy. Results: ASD and A. fumigatus significantly enhanced the production of IL-6 and IL-8 from nasal epithelial cells. By coculturing A. fumigatus with ASD, the dry weight and safranin staining of the fungal biofilms significantly increased in a time-dependent manner. However, the increased level of crystal violet and concanavalin A stain decreased after 72 h of incubation. Conclusions: ASD and A. fumigatus induced the production of inflammatory chemical mediators from nasal epithelial cells. The exposure of A. fumigatus to ASD enhanced the formation of biofilms. The coexistence of ASD and A. fumigatus may increase the development of fungal biofilms and fungal inflammatory diseases in the sinonasal mucosa.     

Studies on the preparation of C/SiC composite as a catalyst support by CVI in a fluidized bed reactor

In this research, in order to improve the mechanical strength and oxidation resistance of a catalyst support, we studied the formation of SiC layer on the pore surfaces of activated carbons by permeating and depositing SiC from a reaction between hydrogen and dichlorodimethylsilane (DDS). The porous structure should be kept during deposition. A fluidized bed reactor and activated carbons of size of 20-40 mesh were used. By studying characteristics of deposits under various deposition conditions, we confirmed that the best conditions of manufacturing catalyst support are a lower pressure and a lower concentration. In this work, at the conditions of 5 torr of total pressure and 3% of DDS concentration, during the 10 hr processing time, deposition occurred on the pore walls before plugging pores. The results from the mathematical modeling were compared with the experimental results.     

Comparison of pollutant loading estimation using different land uses and stormwater characteristics in Ballona Creek Watershed.

Estimation of stormwater pollutant loads using land use based models has been widely used for establishing regulations and management practices. This approach requires land use information to assign the imperviousness or runoff coefficients (RC) and event mean concentrations (EMCs) for the pollutants of interest. This simplistic approach is useful to estimate the total mass emissions. However, different research groups have used various parameters based upon similar data sources, and there are very few validations using actual field data. This study compares the assumptions, methodologies and results of several, independent modelling efforts, and functions as a quality and sensitivity study of the methodologies. The similarity or differences of the various model results serve as a qualitative indicator of the state of art for this type of stormwater modelling.     

Protective effects of chebulic acid from Terminalia chebula Retz. against t-BHP-induced oxidative stress by modulations of Nrf2 and its related enzymes in HepG2 cells

Food Science and Biotechnology - Although chebulic acid isolated from Terminalia chebular has diverse biological effects, its effects on the expression of nuclear factor erythroid 2-related factor...     

Physiological mechanism underlying the improvement in visuospatial performance due to 30% oxygen inhalation

This study investigated the effect of 30% oxygen inhalation on visuospatial cognitive performance, blood oxygen saturation, and heart rate. Six male (25.8(mean)+/-1.0(SD) years) and six female (23.8+/-1.9 years) college students participated in this experiment. Two psychological tests were developed to measure the performance level of visuospatial cognition. The experiment consisted of two runs: one was a visuospatial cognition task under normal air (21% oxygen) condition and the other under hyperoxic air (30% oxygen) condition. The experimental sequence in each run consisted of four phases, that were Rest1 (1min), Control (1min), Task (4min), and Rest2 (4min). Blood oxygen saturation and heart rate were measured throughout the course of four phases. The analysis of behavioral performance with 30% oxygen administration when compared to 21% oxygen revealed that the mean performance was improved. When supplied 30% oxygen in the air, the blood oxygen saturation was increased while the heart rate was decreased compared to those under 21% oxygen condition. We conclude that 30% oxygen inhalation enhanced visuospatial performance by the increased the oxygen saturation in the blood.     

The modified SWAT model for predicting fecal coliforms in the Wachusett Reservoir Watershed, USA

This study assessed fecal coliform contamination in the Wachusett Reservoir Watershed in Massachusetts, USA using Soil and Water Assessment Tool (SWAT) because bacteria are one of the major water quality parameters of concern. The bacteria subroutine in SWAT, considering in-stream bacteria die-off only, was modified in this study to include solar radiation-associated die-off and the contribution of wildlife. The result of sensitivity analysis demonstrates that solar radiation is one of the most significant fate factors of fecal coliform. A water temperature-associated function to represent the contribution of beaver activity in the watershed to fecal contamination improved prediction accuracy. The modified SWAT model provides an improved estimate of bacteria from the watershed. Our approach will be useful for simulating bacterial concentrations to provide predictive and reliable information of fecal contamination thus facilitating the implementation of effective watershed management.     

Utility of LANDSAT-Derived Land Use Data for Estimating Storm-Water Pollutant Loads in an Urbanizing Area

In many watersheds located in southern California, efforts are being focused on urban runoff because of its adverse impact on receiving water quality. The Sweetwater River watershed is a good example, where the drainage area is rapidly urbanizing and deteriorating reservoir water quality. Contaminated storm water is captured and diverted but as urbanization increases, additional runoff will be generated which will overload the existing infrastructure. To better manage the diversion systems and minimize future construction, storm-water volumes and pollutant loadings need to be estimated. Due to the lack of real-time storm-water runoff monitoring data, pollutant loadings must be estimated from land use information. We used satellite imagery to estimate selected storm-water pollutant loads and compared the results to predictions using land use information from public records. Satellite imagery was useful in estimating storm-water pollutant loads and identifying high loading areas. Satellite imagery with appropriate classification is a promising tool for watershed management and for prioritizing best management practices.     

Characterization of N-glycan structures and biofunction of anti-colorectal cancer monoclonal antibody CO17-1A produced in baculovirus-insect cell expression system

Advantages of the baculovirus insect cell expression system for production of recombinant proteins include high capacity, flexibility, and glycosylation capability. In this study, this expression system was exploited to produce anti-cancer monoclonal antibody (mAb) CO17-1A, which recognizes the antigen GA733. The heavy chain (HC) and light chain (LC) genes of mAb CO17-1A were cloned under the control of P₁₀ and Polyhedrin promoters in the pFastBac™ dual vector, respectively. Gene expression cassettes carrying the HC and LC genes were transposed into a bacmid in Escherichia coli (DH10Bac). The transposed bacmid was transfected to Sf9 insect cells to generate baculovirus expressing mAb CO17-1A. Confocal immunofluorescence and Western blot analyses confirmed expression of mAb CO17-1A in baculovirus-infected insect cells. The optimum conditions for mAb expression were evaluated at 24, 48, and 72 h after the virus infection at an optimum virus multiplicity of infection of 1. Expression of mAb CO17-1A in insect cells significantly increased at 72 h after infection. HPLC analysis of glycosylation status revealed that the insect-derived mAb (mAb^I) CO17-1A had insect specific glycan structures. ELISA showed that the purified mAb^I from cell culture supernatant specifically bound to SW948 human colorectal cancer cells. Fluorescence-activated cell sorting analysis showed that, although mAb^I had insect specific glycan structures that differed from their mammalian counterparts, mAb^I similarly interacted with CD64 (FcγRI) and Fc of IgG, compared to the interactions of mammalian-derived mAb. These results suggest that the baculovirus insect cell expression system is able to express, assemble, and secrete biofunctional full size mAb.     

Comparison of gait and cognitive function among the elderly with Alzheimer’s Disease, Mild Cognitive Impairment and Healthy

The purpose of this study was to compare gait pattern and cognitive function among elderly patients with Alzheimer’s Disease (AD), elderly people with Mild Cognitive Impairment (MCI), and Healthy Controls (HC). Twenty three elderly patients participated: 10 AD (77.2±6.84 yrs), 7 MC I(72.9±6.28 yrs), and 6 HC (71.6±5.78 yrs). Gait and Cognitive function were collected using an accelerometer attached to the foot and the Korean version of the Consortium to Establish a Registry for Alzheimer’s Disease (CREAD-K), respectively. To compare differences in gait performance among groups, mean stride time, magnitude and structure of gait variability and ratio of low frequency and high frequency (LF/HF ratio) of stride time sequence were used in this study. Results showed that gait variables (mean stride time, LF/HF ratio of stride time) were useful for classification between MCI and HC. Cognitive function (T1, T3, T4, T6, and T8 of CREAD-K) represented the difference between AD and HC. This study may provide a foundation for future work on progression of dementia.     

Inhibitory effect of yellow myrobalan (Terminalia chebula) extract on fibrosis induced by carbon tetrachloride in rat liver

Ethyl acetate layer of methanol extract (TCE) of yellow myrobalan (Terminalia chebula) contains 2.4% of chebulic acid, a standard compound in TCE, which have a strong anti-oxidative effect and was reported in our previous study. Thirty-one male SD rats were randomly divided into 5 groups (normal control, CCl₄ control, TCE control, CCl₄+high dose TCE, and low dose TCE). Liver fibrosis was induced by i.p. injection of CCl₄ and TCE were orally administrated. TCE decreased the up-regulated malondealdehyde value and increased the down-regulated ratio of GSH/GSSG content and activities of GRd, GPx, and GST compared to the CCl₄ control group. Decreased dysfunction and inflammatory reaction in liver was confirmed by alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels, relative liver weight and infiltration of neutrophils. Also, TCE inhibited phenotype change of hepatic stellate cells (HSC) by reducing α-smooth muscle actin (α-SMA) gene expression and protein production. Inhibition of collagen 1A1 gene expression and protein production were also confirmed. From these results, TCE may be a useful material for preventing liver fibrosis.