• Korean Journal of Radiology
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• v.21 no.10
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• pp.1150-1160
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• 2020

Objective: To describe the experience of implementing a deep learning-based computer-aided detection (CAD) system for the interpretation of chest X-ray radiographs (CXR) of suspected coronavirus disease (COVID-19) patients and investigate the diagnostic performance of CXR interpretation with CAD assistance. Materials and Methods: In this single-center retrospective study, initial CXR of patients with suspected or confirmed COVID-19 were investigated. A commercialized deep learning-based CAD system that can identify various abnormalities on CXR was implemented for the interpretation of CXR in daily practice. The diagnostic performance of radiologists with CAD assistance were evaluated based on two different reference standards: 1) real-time reverse transcriptase-polymerase chain reaction (rRT-PCR) results for COVID-19 and 2) pulmonary abnormality suggesting pneumonia on chest CT. The turnaround times (TATs) of radiology reports for CXR and rRT-PCR results were also evaluated. Results: Among 332 patients (male:female, 173:159; mean age, 57 years) with available rRT-PCR results, 16 patients (4.8%) were diagnosed with COVID-19. Using CXR, radiologists with CAD assistance identified rRT-PCR positive COVID-19 patients with sensitivity and specificity of 68.8% and 66.7%, respectively. Among 119 patients (male:female, 75:44; mean age, 69 years) with available chest CTs, radiologists assisted by CAD reported pneumonia on CXR with a sensitivity of 81.5% and a specificity of 72.3%. The TATs of CXR reports were significantly shorter than those of rRT-PCR results (median 51 vs. 507 minutes; p < 0.001). Conclusion: Radiologists with CAD assistance could identify patients with rRT-PCR-positive COVID-19 or pneumonia on CXR with a reasonably acceptable performance. In patients suspected with COVID-19, CXR had much faster TATs than rRT-PCRs.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.2
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• pp.109-115
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• 2016

The efficacy of depuration following growing area translocation for the defecation of norovirus was evaluated under experimental conditions using oysters Crassostrea gigas previously subjected to bioaccumulation of this virus at a waste treatment plant discharge site. Three trials were assayed in an open experimental system with a commercial oyster farm located in a shellfish growing area approved by the Korean Shellfish Sanitation Program. Real-time reverse-transcription polymerase chain reaction (RT-PCR) was used to quantify viruses in the digestive glands of oysters. The final viral loads in oysters after 12 days remained under the detection limit (10 copies/g digestive gland) of the real-time RT-PCR. This reduction trend showed two-phase removal kinetics, with an initial slow reduction or slight increase in viruses during the first 2 days of depuration and subsequent stabilization with 0.12 to 2.64 log unit norovirus copies/g digestive gland per 2 days of depuration for the remaining time.

• Journal of Ginseng Research
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• v.46 no.6
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• pp.801-808
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• 2022

Background: Diesel exhaust particle (DEP) is a harmful kind of particulate matter known to exacerbate pre-existing respiratory diseases. Although their adverse effects on airway pathologies have been widely studied, the mechanistic analysis of signaling pathways and potential targets in reducing DEP-induced mucin secretion and pro-inflammatory cytokine production remain elusive. We, for the first time, investigated the effects of Korean Red Ginseng (KRG) extracts on mucin overproduction and airway inflammation induced by DEP. Methods: The effects of KRG and saponin on DEP-induced expression of MUC5AC and interleukin (IL)-6/8 were examined by real-time polymerase chain reaction (PCR) and enzyme-linked immunosorbent assay (ELISA) in human airway epithelial NCI-H292 cells. We conducted Western blotting analysis to analyze the associated signaling pathways. To evaluate the effects of saponin treatment on DEP-induced MUC5AC expression and inflammatory cell infiltrations in ovalbumin (OVA)-sensitized mice, immunohistochemical (IHC) staining and real-time PCR were implemented. Results: The KRG extracts markedly attenuated DEP-induced MUC5AC expression in vitro by inhibiting the TLR4/TRIF/NF-𝛋B pathway. Furthermore, KRG and saponin inhibited DEP-induced pro-inflammatory cytokine IL-6/8 production. The in vivo study revealed that saponin blocked DEP-induced inflammation, mucin production and MUC5AC expression. Conclusion: Our study revealed that KRG extracts have inhibitory effects on DEP-induced expression of MUC5AC and the production of pro-inflammatory cytokines. This finding provides novel insights into the mechanism by which saponin alleviates diesel-susceptible airway inflammation, elucidating its potential as a phytotherapeutic agent for inflammatory pathologies of airway.

• Restorative Dentistry and Endodontics
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• v.30 no.5
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• pp.372-384
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• 2005

The purpose of this study was to monitor the secretion of matrix metalloproteinase (MMP) and tissue inhibitor of metalloproteinase (TIMP) by human periodontal ligament (PDL) fibroblasts stimulated with Prevotella nigrescens lipopolysaccharide (LPS), and to examine the effect of calcium hydroxide treatment on P. nigrescens LPS. LPS was extracted and purified from anaerobically cultured P. nigrescens. PDL fibroblasts were stimulated by the LPS (0, 0.1, 1, 10 ${\mu}g/ml$) or LPS (10 ${\mu}g/ml$) pretreated with 12.5 mg/ml of $Ca(OH)_2$ for 3 days, for various periods of time (12, 24, 48 h). Immunoprecipitation were performed for protein level analysis of MMP-1 MMP-2 and TIMP-1. Total RNA was isolated and real-time quantitative polymerase chain reaction (PCR) was performed for quantification of MMP-1 mRNA. According to this study, the results were as follows: 1. The p개duction of MMP-1 by stimulation with P. nigrescens LPS increased in time-dependent manner, and showed maximum value at 48 h in both protein and mRNA level. But there was no dose-dependent increas. 2. MMP-2 production time-dependently increased when stimulated with 1 and 10 ${\mu}g/ml$LPS, but there was no dose-dependent increase. 3. TIMP-1 p개duction increased to 24 h, but decreased at 48 h. It increased when stimulated with 0.1 and 1${\mu}g/ml$, but suppressed at 10 ${\mu}g/ml$ .4. P. nigrescens LPS pretreated with $Ca(OH)_2$ markedly downregulated MMP-1 gene expression.

• Korean Journal of Veterinary Service
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• v.42 no.1
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• pp.31-37
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• 2019

There have been a total tenth FMD outbreaks in Korea and for the first time, type O and A were detected simultaneously in 2017, which led to difficulties in FMD control. For the effective prevention of FMD, the importance of discrimination of serotypes became greater. Therefore, the most urgent requirement in case of FMD outbreak is differential diagnosis of serotypes. In this study, we developed a PNA probe-mediated multiplex real-time reverse transcription-polymerase chain reaction (rRT-PCR) assay using the peptide nucleic acid (PNA) probe, which is known to be stable to nucleotide mutation and that could specifically detect the all FMDV serotype A, FMDVA Yeoncheon strain which was occurred in Korea in 2017, and FMDV A viruses shown 96% similarity with FMDVA/Yeoncheon strain, at the same time. Therefore, It is believed that the newly introduced FMDVA will be effectively diagnosed using the PNA probe multiplex RT-PCR developed in this study, and ultimately contribute to the prevention of FMD.

• Journal of Embryo Transfer
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• v.24 no.2
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• pp.77-87
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• 2009

To understand molecular and cellular mechanisms of many gene products in the female reproductive organs including the ovary and uterine endometrium as well as during embryo development, researchers have developed and utilized many effective methodologies to analyze gene expression in cells, tissues and animals over the last several decades. For example, blotting techniques have helped to understand molecular functions at DNA, RNA and protein levels, and the reverse transcription-polymerase chain reaction (RT-PCR) method has been widely used in gene expression analysis. However, some conventional methods are not sufficient to understand regulation and function of genes expressed in very complex patterns in many organs. Thus, it is required to adopt more high-throughput and reliable techniques. Here, we describe several techniques used widely recently to analyze gene expression, including annealing control based-PCR, differential display-PCR, expressed sequence tag, suppression subtractive hybridization and microarray techniques. Use of these techniques will help to analyze expression pattern of many genes from small scale to large scale and to compare expression patterns of genes in one sample to another. In this review, we described principles of these methodologies and summarized examples of comparative analysis of gene expression in female reproductive organs with help of those methodologies.

• Journal of Medicine and Life Science
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• v.20 no.3
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• pp.107-114
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• 2023

Epidemiological control of coronavirus disease 2019 (COVID-19) is needed to estimate the infection period of confirmed cases and identify potential cases. The present study, targeting confirmed cases for which the time of COVID-19 symptom onset was disclosed, aimed to investigate the relationship between intervals (day) from symptom onset to testing the cycle threshold (CT) values of real-time reverse transcription-polymerase chain reaction. Of the COVID-19 confirmed cases, those for which the date of suspected symptom onset in the epidemiological investigation was specifically disclosed were included in this study. Interval was defined as the number of days from symptom onset (as disclosed by the patient) to specimen collection for testing. A locally weighted regression smoothing (LOWESS) curve was applied, with intervals as explanatory variables and CT values (CTR for RdRp gene and CTE for E gene) as outcome variables. After finding its non-linear relationship, a polynomial regression model was applied to estimate the 95% confidence interval values of CTR and CTE by interval. The application of LOWESS in 331 patients identified a U-shaped curve relationship between the CTR and CTE values according to the number of interval days, and both CTR and CTE satisfied the quadratic model for interval days. Active application of these results to epidemiological investigations would minimize the chance of failing to identify individuals who are in contact with COVID-19 confirmed cases, thereby reducing the potential transmission of the virus to local communities.

• The Plant Pathology Journal
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• v.39 no.6
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• pp.614-624
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• 2023

Botrytis cinerea is a major fungal plant pathogen that causes gray mold disease in strawberries, leading to a decrease in strawberry yield. While benzimidazole is widely used as a fungicide for controlling this disease, the increasing prevalence of resistant populations to this fungicide undermines its effectiveness. To investigate benzimidazole resistant B. cinerea in South Korea, 78 strains were isolated from strawberries grown in 78 different farms in 2022, and their EC₅₀ values for benzimidazole were examined. As a result, 64 strains exhibited resistance to benzimidazole, and experimental tests using detached strawberry leaves and the plants in a greenhouse confirmed the reduced efficacy of benzimidazole to control these strains. The benzimidazole resistant strains identified in this study possessed two types of mutations, E198A or E198V, in the TUB2 gene. To detect these mutations, TaqMan probes were designed, enabling rapid identification of benzimidazole resistant B. cinerea in strawberry and tomato farms. This study utilizes TaqMan real-time polymerase chain reaction analysis to swiftly identify benzimidazole resistant B. cinerea, thereby offering the possibility of effective disease management by identifying optimum locations and time of application.

• IMMUNE NETWORK
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• v.9 no.1
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• pp.27-33
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• 2009

Macrophages generated in vitro using macrophage-colony stimulating factor (M-CSF) and interleukin (IL)-6 from bone marrow cells (BM-Mp) are defective in antigen presenting cell (APC) function as shown by their ability to induce the proliferation of anti-CD3 mAb-primed syngeneic T cells. However, they do express major histocompatibility (MHC) class I and II molecules. accessory molecules and intracellular adhesion molecules. Here we demonstrate that the defective APC function of macrophages is mainly due to production of $TGF-{\beta}1$ by BM-Mp. Methods: Microarray analysis showed that $TGF-{\beta}1$ was highly expressed in BM-Mp, compared to a macrophage cell line, B6D. which exerted efficient APC function. Production of $TGF-{\beta}1$ by BM-Mp was confirmed by neutralization experiments of $TGF-{\beta}1$ as well as by real time-polymerase chain reaction (PCR). Results: Addition of $anti-TGF-{\beta}1$ monoclonal antibody to cultures of BM-Mp and anti-CD3 mAb-primed syngeneic T cells efficiently induced the proliferation of syngeneic T cells. Conversely, the APC function of B6D cells was almost completely suppressed by addition of $TGF-{\beta}1$. Quantitative real time-PCR analysis also confirmed the enhanced expression of $TGF-{\beta}1$ in BM-Mp. Conclusion: The defective APC function of macrophages generated in vitro with M-CSF and IL-6 was mainly due to the production of $TGF-{\beta}1$ by macrophages.

• The Korean Journal of Physiology and Pharmacology
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• v.15 no.1
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• pp.23-29
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• 2011

Melatonin, which is the main product of the pineal gland, has well documented antioxidant and immune-modulatory effects. Macrophages produce molecules that are known to play roles in inflammatory responses. We conducted microarray analysis to evaluate the global gene expression profiles in response to treatment with melatonin in lipopolysaccharide (LPS) activated RAW 264.7 macrophage cells. In addition, eight genes were subjected to real-time reverse transcription polymerase chain reaction (RT-PCR) to confirm the results of the microarray. The cells were treated with LPS or melatonin plus LPS for 24 hr. LPS induced the up-regulation of 1073 genes and the down-regulation of 1144 genes when compared to the control group. Melatonin pretreatment of LPS-stimulated RAW 264.7 cells resulted in the down regulation of 241 genes and up regulation of 164 genes. Interestingly, among genes related to macrophage-mediated immunity, LPS increased the expression of seven genes (Adora2b, Fcgr2b, Cish, Cxcl10, Clec4n, Il1a, and Il1b) and decreased the expression of one gene (Clec4a3). These changes in expression were attenuated by melatonin. Furthermore, the results of real-time PCR were similar to those of the microarray. Taken together, these results suggest that melatonin may have a suppressive effect on LPS-induced expression of genes involved in the regulation of immunity and defense in RAW 264.7 macrophage cells. Moreover, these results may explain beneficial effects of melatonin in the treatment of various inflammatory conditions.