• Journal of Dairy Science and Biotechnology
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• 제31권2호
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• pp.171-177
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• 2013

The dairy industry has consistently grown via the expansion of dairy-based food categories. Dairy product consumption is stable since the nutrient composition in dairy products is ideal for human health. However, dairy products are highly susceptible to food-borne pathogens. Controlling the safety of dairy products is thus important when considering the nutrient-rich matrix of this food category. Currently, immunoassays or molecular biology techniques have been used to evaluate the safety of dairy products in Korea. These methods are based on the detection of proteins and thus have low reproducibility and sensitivity. Recent techniques to detect food-borne pathogens have focused on genetic analyses. Rapid detection methods for food-borne pathogens in milk and dairy products using polymerase chain reaction (PCR) techniques, such as conventional PCR, real-time PCR, repetitive sequence-based (rep)-PCR, PCR-denaturing gradient gel electrophoresis (DGGE), and digital PCR, are reviewed in this article. The aim of this review was to contribute knowledge of the relationship between microflora and the quality of dairy products. This study will also assist in the immediate monitoring of food-borne pathogens in milk and dairy products when an outbreak related to this food category occurs.

• Neonatal Medicine
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• 제25권4호
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• pp.144-152
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• 2018

Purpose: The aim of this study was to investigate the clinical characteristics of Respiratory syncytial virus (RSV) infection during the neonatal period to provide information that is useful in clinical practice and suggest extension of the palivizumab administration. Methods: Neonates admitted to the National Health Insurance Service Ilsan Hospital neonatal intensive care unit due to respiratory symptoms and for whom multiplex reverse transcription-polymerase chain reaction and multiplex real time-polymerase chain reaction tests were performed between October 2011 and May 2016 were included in this study. Medical records were retrospectively reviewed, and data was collected for 156 neonates. Results: Among the 156 neonates, RSV was detected in 114 (73.1%), non-RSV in 25 (16%), and no virus in 17 (10.9%). The majority were full term infants (92.4%) and peak incidence of RSV infection was in January. Post-natal care center infection was more common in the RSV group (46.6%) than that in the other virus groups (24%, P=0.0243). Clinical symptoms were severe in the RSV group in contrast to that in the non-RSV or others groups. The RSV group frequently needed oxygen therapy (P=0.0001) and the duration of hospital stays were longer (P=0.0001). Conclusion: RSV is a significant cause of respiratory infection in neonates and the severity is higher in contrast to that with other viral causes of infection. Infants in post-natal care centers have a high-risk of developing RSV infections; therefore, palivizumab administration may be considered in this group to prevent hospitalization and reduce the duration of hospital stay.

• Animal Bioscience
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• 제36권1호
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• pp.156-166
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• 2023

Objective: In this study, we investigated the effects of Rubus coreanus-derived lactic acid bacteria (LAB) fermented feed (RC-LAB fermented feed) and three types of LAB (Lactobacillus plantarum, Lactobacillus acidophilus, Bifidobacterium animalis) on the expression of transcription factors and cytokines in Th1, Th2, Th17, and Treg cells in the intestinal lymph nodes and spleens of rats. In addition, the effect on intestinal microbiota composition and body weight was investigated. Methods: Five-week-old male rats were assigned to five treatments and eight replicates. The expression of transcription factors and cytokines of Th1, Th2, Th17, and Treg cells in the intestinal lymph nodes and spleens was analyzed using real-time reverse transcriptase polymerase chain reaction assays. Intestinal tract microbiota compositions were analyzed by next-generation sequencing and quantitative polymerase chain reaction assays. Results: RC-LAB fermented feed and three types of LAB increased the expression of transcription factors and cytokines in Th1, Treg cells and Galectin-9, but decreased in Th2 and Th17 cells. In addition, the intestinal microbiota composition changed, the body weight and Firmicutes to Bacteroidetes (F/B) ratio decreased, and the relative abundance of LAB increased. Conclusion: LAB fermented feed and three types of LAB showed an immune modulation effect by inducing T cell polarization and increased LAB in the intestinal microbiota.

• 농업과학연구
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• 제49권4호
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• pp.881-892
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• 2022

Fire blight in apple and pear orchards, caused by Erwinia amylovora, is a global problem. Ongoing outbreaks have occurred since 2015. In 2020, 744 orchards were infected compared with 43 orchards in 2015 in Korea. When are insufficient. In Korea, all host plants in infected orchards are buried deeply with lime to eradicate the E. amylovora outbreak within a few days. Apple trees with infected trunks and branches and twigs with infected leaves and infected blooms were collected from an apple orchard in Chungju, Chungbuk province, where fire blight occurred in 2020. We used these samples to investigate the population density and internal distribution of E. amylovora on infected branches and twigs during early season infections. Infected branches and twigs were cut at 10 cm intervals from the infected site, and E. amylovora was isolated from tissue lysates to measure population density (colony-forming unit [CFU]·mL^-1). The polymerase chain reaction was performed on genomic DNA using E. amylovora specific primers. Real-time polymerase chain reaction (PCR) was performed to detect E. amylovora in asymptomatic tissue. The objective of these assays was to collect data relevant to the removal of branches from infected trees during early season infection. In infected branches, high densities of greater than 10⁶ CFU·mL^-1 E. amylovora were detected within 20 cm of the infected sites. Low densities ranging from 10² to 10⁶ CFU·mL^-1 E. amylovora were found in asymptomatic tissues at distances of 40 - 75 cm from an infection site.

• Asian-Australasian Journal of Animal Sciences
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• 제30권3호
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• pp.328-337
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• 2017

Objective: An experiment was conducted to determine the relationship between the KAP11.1 and the regulation wool fineness. Methods: In previous work, we constructed a skin cDNA library and isolated a full-length cDNA clone termed KAP11.1. On this basis, we conducted a series of bioinformatics analysis. Tissue distribution of KAP11.1 mRNA was performed using semi-quantitative reverse transcription polymerase chain reaction (RT-PCR) analysis. The expression of KAP11.1 mRNA in primary and secondary hair follicles was performed using real-time PCR (real-time polymerase chain reaction) analysis. The expression location of KAP11.1 mRNA in primary and secondary hair follicles was performed using in situ hybridization. Results: Bioinformatics analysis showed that KAP11.1 gene encodes a putative 158 amino acid protein that exhibited a high content of cysteine, serine, threonine, and valine and has a pubertal mammary gland) structural domain. Secondary structure prediction revealed a high proportion of random coils (76.73%). Semi-quantitative RT-PCR showed that KAP11.1 gene was expressed in heart, skin, and liver, but not expressed in spleen, lung and kidney. Real time PCR results showed that the expression of KAP11.1 has a higher expression in catagen than in anagen in the primary hair follicles. However, in the secondary hair follicles, KAP11.1 has a significantly higher expression in anagen than in catagen. Moreover, KAP11.1 gene has a strong expression in inner root sheath, hair matrix, and a lower expression in hair bulb. Conclusion: We conclude that KAP11.1 gene may play an important role in regulating the fiber diameter.

• 생명과학회지
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• 제25권2호
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• pp.136-150
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• 2015

Pseudomonas syringae pv. tabaci 11528은 담배를 숙주로 하여 wildfire disease를 일으키는 식물 병원성 세균이다. P. syringae pv. tabaci psyR deletion mutant를 이용하여 swarming motility, tabtoxin 생산능, siderophore 생산능, AHL 생산능 등의 phenotypic test를 수행하였다. psyR deletion mutant는 wild-type 균주보다 swarming motility가 증가하였고, tabtoxin 생산 또한 증가하였다. 하지만 siderophore와 AHL 생산능은 감소하였고 virulence 또한 지연되었다. 이러한 결과로 PsyR이 QS regulator로 작용한다는 사실과 더불어 병원성 유전자의 조절에도 관여한다는 것을 확인하였다. PsyR이 각각의 병원성 유전자의 발현을 조절하는 regulator들에게 미치는 영향을 전사단계에서 확인하기 위해 fur, gacA, psyI, prhI, prhA, hrpR, hrpA 유전자들을 정량적 real-time PCR (qRT-PCR) 방법으로 확인하였다. 또한 PsyR에 의한 병원성 유전자 조절이 DNA상에 직접적으로 결합하여 일어나는 것인지 아니면 다른 경로를 통해 간접적으로 일어나는 것인지를 확인할 필요가 있어 정제한 PsyR 단백질과 병원성 관련 유전자들의 upstream region 서열을 이용하여 electrophoretic mobility shift assay (EMSA)를 수행한 결과 본 연구에서 선정한 병원성 관련 유전자들이 PsyR에 의해 직접적으로 조절되지는 않는다는 사실을 밝혔다.

• 한국동물위생학회지
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• 제45권1호
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• pp.1-11
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• 2022

A novel porcine circovirus 4 (PCV4) was recently identified in Chinese and Korean pig herds. Although several conventional polymerase chain reaction (cPCR) and real-time PCR (qPCR) assays were used for PCV4 detection, more sensitive and reliable qPCR assay is needed that can simultaneously detect PCV4 and internal positive control (IPC) to avoid false-negative results. In the present study, a duplex qPCR (dqPCR) assay was developed using primers/probe sets targeting the PCV4 Cap gene and pig (glyceraldehyde-3-phosphate dehydrogenase) GAPDH gene as an IPC. The developed dqPCR assay was specifically detected PCV4 but not other PCVs and porcine pathogens, indicating that the newly designed primers/probe set is specific to the PCV4 Cap gene. Furthermore, GAPDH was stably amplified by the dqPCR in all tested viral and clinical samples containing pig cellular materials, indicating the high reliability of the dqPCR assay. The limit of detection of the assay 5 copies of the target PCV4 genes, but the sensitivity of the assay was higher than that of the previously described assays. The assay demonstrated high repeatability and reproducibility, with coefficients of intra-assay and inter-assay variation of less than 1.0%. Clinical evaluation using 102 diseased pig samples from 18 pig farms showed that PCV4 circulated in the Korean pig population. The detection rate of PCV4 obtained using the newly developed dqPCR was 26.5% (27/102), which was higher than that obtained using the previously described cPCR and TaqMan probe-based qPCR and similar to that obtained using the previously described SYBR Green-based qPCR. The dqPCR assay with IPC is highly specific, sensitive, and reliable for detecting PCV4 from clinical samples, and it will be useful for etiological diagnosis, epidemiological study, and control of the PCV4 infections.

• ALGAE
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• 제26권3호
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• pp.237-241
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• 2011

The toxic dinoflagellate Karlodinium veneficum has been implicated in numerous fish kill events around the world. Since this species commonly co-occurs with other morphologically similar dinoflagellates, field monitoring of this species in natural waters via light microscopy only has been problematic. In this study, we investigated temporal changes in K. veneficum's abundance in the waters of Obido, Tongyeong, using a species-specific real-time polymerase chain reaction (PCR) assay. The field survey, from April to December 2010, revealed K. veneficum occurred at low densities (12 to 425 cells $L^{-1}$) during this time and that cell numbers peaked in June (early summer in Korea), indicating this species generally occurs in the warmer season (mostly at $16.9-22.3^{\circ}C$ and 33.4-34.5‰) in the Obido area.

• Restorative Dentistry and Endodontics
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• 제30권5호
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• pp.372-384
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• 2005

이 연구에서는 Prevotella nigrescens (P. nigrescens)의 lipopolysaccharide (LPS)로 자극한 치주인대 섬유아세포에서 matrix metalloproteinase (MMP)와 tissue inhibitor of metalloproteinase (TIMP)의 생성 양상과, LPS를 수산화칼슘으로 처리했을 때의 영향을 평가하였다. P. nigrescens에서 추출, 정제한 여러 농도의 LPS와 수산화칼슘으로 처리한 LPS로 치주인대 섬유아세포를 자극하여, Immunoprecipitation법으로 MMP-1, -2, TIMP-1의 단백질 생성 양상을, real-time polymerase chain reaction법으로 MMP-1의 mRNA 발현 양상을 분석하였다. 이 연구의 결과는 아래와 같다. 1. MMP-1은 단백질과 유전자 수준 모두 자극 시간과 비례하여 증가하여 48시간에 최대값을 보였다. 2. MMP-2단백질 생성은 1, 10 mg/ml에서 자극 시간과 비례하여 증가하였다. 3. TIMP-1 단백질 생성은 24시간까지 증가하다가 48시간에 감소하였고, 0.1과 1 ${\mg}g/ml$에서 증가하였으나 10 ${\mu}g/ml$ 에서 억제되었다. 4. P. nigrescens의 LPS를 수산화칼슘으로 처리시 MMP-1의 mRNA 발현은 현저하게 감소하였다.

• 미생물학회지
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• 제55권1호
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• pp.25-32
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• 2019

Influenza A (H1N1) virus caused a worldwide pandemic in 2009-2010 and still remains in seasonal circulation. Continuous surveillance activities are encouraged in the post pandemic phase to watch over the trend of occurrence every year, this is better to be done by a rapid and sensitive method for its detection. This study was conducted to detect proportions of occurrence of influenza A virus (H1N1) in patients with influenza-like illness. Samples from 500 patients with influenza or influenza-like clinical presentation were tested by real-time reverse transcription polymerase chain reaction (RT-PCR) and virus tissue culture. Among the total 500 participants, 193 (38.6%) were females and 307 (61.4%) males. Seventy-one patients (14.2%) were positive for H1N1 virus infection with real-time RT-PCR while 52 (10.4%) were positive by tissue culture. Non-statistically significant relation was found between age and gender with the positivity of H1N1. Sensitivity and specificity of real-time RT-PCR was 98.08% and 95.54%, respectively, in comparison to virus isolation with accuracy 95.8%. This study showed that H1N1 virus was responsible for a good proportion of influenza during the post-pandemic period. Real-time RT-PCR provides rapidity and sensitivity for the detection of influenza A virus (H1N1) compared with virus isolation and thus it is recommended as a diagnostic tool.