301 research outputs found
Quercetin 7-rhamnoside reduces porcine epidemic diarrhea virus replication via independent pathway of viral induced reactive oxygen species
<p>Abstract</p> <p>Background</p> <p>On the base of our previous study we were observed relevant studies on the hypothesis that the antiviral activity of quercetin 7-rhamnoside (Q7R), a flavonoid, won't relate ability of its antioxidant.</p> <p>Methods</p> <p>We were investigated the effects of Q7R on the cytopathic effects (CPE) by CPE reduction assay. Production of DNA fragment and reactive oxygen species (ROS) induced by PEDV infection were studied using DNA fragmentation assay and flow cytometry.</p> <p>Results</p> <p>In the course of this study it was discovered that Q7R is an extremely potent compound against PEDV. The addition of Q7R to PEDV-infected Vero cells directly reduced the formation of a visible cytopathic effect (CPE). Also, Q7R did not induce DNA fragmentation. Furthermore, ROS increased the infection of PEDV, which was strongly decreased by N-acetyl-L-cysteins (NAC). However, the increased ROS was not decreased by Q7R. Antiviral activity of antioxidants such as NAC, pyrrolidine dithiocarbamate (PDTC), and the vitamin E derivative, trolox, were hardly noticed.</p> <p>Conclusions</p> <p>We concluded that the inhibition of PEDV production by Q7R is not simply due to a general action as an antioxidants and is highly specific, as several other antioxidants (NAC, PDTC, trolox) are inactive against PEDV infection.</p
In-Plane Strengthening of Unreinforced Masonry Walls by Glass Fiber-Reinforced Polyurea
Strengthening techniques have been employed in Korea to unreinforced masonry walls (UMWs) for several years to protect them from damage caused by the intermittent occurrence of earthquakes. Polyurea, which has a high tensile strength and elongation rate, can be utilized as a strengthening material to enhance the in-plane strength and ductility of UMWs. Glass fiber-reinforced polyurea (GFRPU) is a composite elastomer manufactured by progressively adding milled glass fiber to polyurea. The purpose of this study is to investigate the enhancement of the in-plane strength and ductility of UMWs using GFRPU, depending on the shape of the GFRPU coating on the wall. Four masonry wall specimens are tested with test variables of the number of strengthening sides and coating shapes. It is illustrated that the GFRPU reinforcement of masonry wall leads to enhanced load-carrying capacity, ductility, and energy absorption. An empirical formula to represent the degree of strengthening effected by GFRPU is proposed in this study. Doi: 10.28991/cej-2021-03091782 Full Text: PD
Out-of-Plane Strengthening of Unreinforced Masonry Walls by Glass Fiber-Reinforced Polyurea
Fiber-reinforced polymer reinforcement or polyurea reinforcement techniques are applied to strengthen unreinforced masonry walls (UMWs). The purpose of this experimental study is to verify the out-of-plane reinforcing effect of sprayed glass fiber-reinforced polyurea (GFRPU), which is a composite elastomer made of polyurea and milled glass fibers on UMW. The out-of-plane strengths and ductile behaviors based on various coating shapes are compared in this study. An empirical formula to describe the degree of reinforcement on the out-of-plane strength of the UMW is derived based on the experimental results. It is observed that the peak load-carrying capacity, ductility, and energy absorption capacity gradually improve with an increase in the strengthening degree or area. Compared with the existing masonry wall reinforcement method, the GFRPU technique is a construction method that can help improve the safety performance along with ease of construction and economic efficiency. Doi: 10.28991/CEJ-2022-08-01-011 Full Text: PD
Suprapubic Cystostomy: Risk Analysis of Possible Bowel Interposition Through the Percutaneous Tract by Computed Tomography
Simultaneous Determination of Seven Sesquiterpene Lactone Glucosides in Ixeris dentata by High-Performance Liquid Chromatography Coupled with Tandem Mass Spectrometry and their Antiviral Activities
Ixeris dentata (Thunb. ex Thunb.) Nakai (Asteraceae), a well-known edible vegetable in Asia, contains various bioactive secondary metabolites, including sesquiterpene lactones. In this study, a high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method has been developed and validated for simultaneous determination of seven sesquiterpene lactone glucosides isolated from the roots of I. dentata. In addition, these compounds were evaluated in terms of their antiviral activities against coxsackievirus B3 (CVB3) and human enterovirus 71 (EV71). The developed method was validated in terms of linearity (R-2 > 0.9996), precision (RSD < 2.24%), accuracy (96.30-102.77%), and stability (RSD < 1.94%) and successfully applied to the quantitation of the I. dentata root samples collected from six different regions of Korea. The content of sesquiterpene lactone glucosides varied significantly based on the region. For the antiviral activities, guaianolides with an ester group at C-8 (compounds 6 and 7) showed the most potent activities against CBV3, while germacranolide (compound 5) showed the most consistent antiviral activity against both CVB3 and EV71. The method was validated to be simple and reliable to simultaneously determine seven putative bioactive sesquiterpene lactone glucosides, the substantial chemotaxonomic markers, in I. dentata root samples.1
Spatial and temporal variabilities of spring Asian dust events and their impacts on chlorophyll-a concentrations in the western North Pacific Ocean
Author Posting. © American Geophysical Union, 2017. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geophysical Research Letters 44 (2017): 1474–1482, doi:10.1002/2016GL072124.As the western North Pacific Ocean is located downwind of the source regions for spring Asian dust, it is an ideal location for determining the response of open waters to these events. Spatial analysis of spring Asian dust events from source regions to the western North Pacific, using long-term daily aerosol index data, revealed three different transport pathways supported by the westerly wind system: one passing across the northern East/Japan Sea (40°N–50°N), a second moving over the entire East/Japan Sea (35°N–55°N), and a third flowing predominantly over the Siberian continent (>50°N). Our results indicate that strong spring Asian dust events can increase ocean primary productivity by more than 70% (>2-fold increase in chlorophyll-a concentrations) compared to weak/nondust conditions. Therefore, attention should be paid to the recent downturn in the number of spring Asian dust events and to the response of primary production in the western North Pacific to this change.Korean government (MSIP) Grant Numbers: 2015R1C1A1A01052051, NRF-C1ABA001-2011-0021064;
Korea Polar Research Institute (KOPRI) Grant Number: PE17030;
NOAA Grant Number: NA11OAR4310063;
WHOI2017-08-1
The Effect of Composite Pig Islet-Human Endothelial Cell Grafts on the Instant Blood-Mediated Inflammatory Reaction
Instant blood-mediated inflammatory reaction (IBMIR) causes rapid islet loss in portal vein islet transplantation. Endothelial cells are known to protect against complement-mediated lysis and activation of coagulation. We tested composite pig islet-human endothelial cell grafts as a strategy to overcome IBMIR. Porcine islets were cocultured with human endothelial cells in specially modified culture medium composed of M199 and M200 for 1-9 days. A positive control group, negative control group, and the endothelial cell-coated group were examined with an in vitro tubing loop assay using human blood. The endothelial cell-coated group was subdivided and analyzed by degree of surface coverage by endothelial cells (50%) or coculture time (= 5 days). Platelet consumption and complement and coagulation activation were assessed by platelet count, C3a, and thrombin-antithrombin complex (TAT), respectively. After 60-min incubation in human blood, the endothelial cell-coated group showed platelet consumption inhibition and low C3a and TAT assay results compared to uncoated controls. When the endothelial cell-coated group was subdivided by degree of surface coverage, the <= 50% coated group showed less platelet consumption and less activation of complement and coagulation compared with the positive control (uncoated) group. On analysis by coculture time, only the subgroup cocultured for <5 days showed the same protective effect. Human endothelial cell-coated pig islets, especially the partially coated and short-term cocultured pig islet-human endothelial cell composites, reduced all components of IBMIR. If the optimal endothelial cell-islet coculture method could be identified, human endothelial cell coating of pig islets would offer new strategies to improve xenogenic islet transplantation outcomes.McGuigan AP, 2007, BIOMATERIALS, V28, P2547, DOI 10.1016/j.biomaterials.2007.01.039Kim JH, 2007, XENOTRANSPLANTATION, V14, P60, DOI 10.1111/j.1399-3089.2006.00364.xCowan PJ, 2007, XENOTRANSPLANTATION, V14, P7, DOI 10.1111/j.1399-3089.2006.00368.xJones GL, 2007, CELL TRANSPLANT, V16, P505Johansson U, 2005, AM J TRANSPLANT, V5, P2632, DOI 10.1111/j.1600-6143.2005.01076.xKorsgren O, 2005, TRANSPLANTATION, V79, P1289, DOI 10.1097/01.TP.0000157273.60147.7CVenturini M, 2005, RADIOLOGY, V234, P617, DOI 10.1148/radiol.2342031356Goto M, 2004, TRANSPLANTATION, V77, P741, DOI 10.1097/01.TP.0000114872.26990.4FSzmitko PE, 2003, CIRCULATION, V107, P3093, DOI 10.1161/01.CIR.0000074242.66719.4ALinn T, 2003, FASEB J, V17, P881, DOI 10.1096/fj.02-0615fjeOzmen L, 2002, DIABETES, V51, P1779Buhler L, 2002, XENOTRANSPLANTATION, V9, P3Bennet W, 2001, TRANSPLANTATION, V72, P312Bennet W, 2000, TRANSPLANTATION, V69, P711Bennet W, 1999, DIABETES, V48, P1907ANTONOV AS, 1992, THROMB RES, V67, P135SPEISER W, 1987, BLOOD, V69, P964KUMAR S, 1987, DIFFERENTIATION, V36, P57MADRI JA, 1983, J CELL BIOL, V97, P153
Prevalence and Risk Factor of Erosive Esophagitis Observed in Korean National Cancer Screening Program
Prevalence of erosive esophagitis (EE) has been increasing in Korea. The purpose of this study was to estimate prevalence of EE among low socioeconomic population in Korea and to investigate risk factors for EE. We reviewed the medical records of 7,278 subjects who were examined by upper endoscopy in the Korean National Cancer Screening Program at Chung-Ang University Yong-san Hospital from March 2003 to March 2008. The study population included subjects ≥ 40 yr of age who were Medicaid recipients and beneficiaries in the National Health Insurance Corporation. Multivariate analysis was used to determine risk factors for EE. Prevalence of EE was 6.7% (486/7,278). According to the LA classification system, LA-A in 344 subjects, LA-B in 135 subjects, and LA-C and D in 7 subjects. In multivariate analysis, age ≥ 60 yr, male sex, BMI ≥ 25, current smoking, alcohol consumption, fasting glucose level ≥ 126 mg/dL, and endoscopic hiatal hernia were significant risk factors for EE. The prevalence of EE in low socioeconomic Korean population is similar to that in personal annual medical check-ups. Risk factors for EE among them include old age, male sex, BMI ≥ 25, current smoking, alcohol consumption, fasting glucose level ≥ 126 mg/dL, and hiatal hernia
MCP-1 and RANTES Polymorphisms in Korean Diabetic End-Stage Renal Disease
Macrophage infiltration has been observed in the renal biopsy specimens of diabetic nephropathy (DN), and hyperglycemic state stimulates the renal expression of RANTES (regulated upon activation, normal T-cell expressed and secreted) and MCP-1 (monocyte chemoattractant protein-1). Upregulation of RANTES and MCP-1 with infiltrating macrophages may play a crucial role in the development and progression of DN. Genetic polymorphisms of RANTES and its receptors were reported to be independent risk factors for DN. We genotyped single nucleotide polymorphism (SNPs) in the MCP-1 G-2518A, CCR2 G46295A, RANTES C-28G and G-403A in 177 diabetic end-stage renal disease (ESRD) patients and 184 patients without renal involvement (controls) in order to investigate the effects of these SNPs on DN in Korean patients with type 2 DM. There were no differences in the frequencies of SNPs and the distribution of haplotypes of RANTES promoter SNPs between two groups. In conclusion, there were no associations of MCP-1, CCR2 and RANTES promoter SNPs with diabetic ESRD in Korean population. Prospective studies with clearly-defined, homogenous cohorts are needed to confirm the effect of these genetic polymorphisms on DN
Comparative analysis of the pig gut microbiome associated with the pig growth performance
There are a variety of microorganisms in the animal intestine, and it has been known that they play important roles in the host such as suppression of potentially pathogenic microorganisms, modulation of the gut immunity. In addition, the gut microbiota and the livestock growth performance have long been known to be related. Therefore, we evaluated the interrelation between the growth performance and the gut microbiome of the pigs from 3 different farms, with pigs of varied ages ready to be supplied to the market. When pigs reached average market weight of 118 kg, the average age of pigs in three different farms were < 180 days, about 190 days, and > 200 days, respectively. Fecal samples were collected from pigs of age of 70 days, 100 days, 130 days, and 160 days. The output data of the 16S rRNA gene sequencing by the Illumina Miseq platform was filtered and analyzed using Quantitative Insights into Microbial Ecology (QIIME)2, and the statistical analysis was performed using Statistical Analysis of Metagenomic Profiles (STAMP). The results of this study showed that the gut microbial communities shifted as pigs aged along with significant difference in the relative abundance of different phyla and genera in different age groups of pigs from each farm. Even though, there was no statistical differences among groups in terms of Chao1, the number of observed operational taxonomic units (OTUs), and the Shannon index, our results showed higher abundances of Bifidobacterium, Clostridium and Lactobacillus in the feces of pigs with rapid growth rate. These results will help us to elucidate important gut microbiota that can affect the growth performance of pigs
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