• Korean journal of applied entomology
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• v.4
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• pp.29-32
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• 1965

1. The 30 isolates of Xanthomonas oryzae collected from various places in Korea were classified into 2 strains in A' and B, by the 4 kinds of Japanese bacteriophages as follow; A' strain; Susceptible to $OP_1$ and $OP_2$ but not to $OP_1h$ and $OP_1h_2$. B strain; Susceptible to $OP_1h$, $OP_1h_2$ and $OP_2$ but not to $OP_1$. Of these bacterial strains, A' strain, a little different to A strain in Japan, was susceptible to $OP_1h_2$, while A' strain was resistant to $OP_1h_2$, 2. A' strain was widely and commonly distributed throughout this country, In geographical distribution, it was generally known that A' strain was distributed in south of Kyunggi-Do, whereas B strain was distributed north of Suwon area. 3. No specific tendency was found in the distribution of these strains in same variety.

• Journal of Plant Biotechnology
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• v.45 no.3
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• pp.217-227
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• 2018

Gummy stem blight (GSB) is one of the most destructive and economically important, soil borne diseases of melon caused by the ascomycete fungus, Didymella bryoniae throughout the world. In Korea, however, no GSB resistant genotype has been reported yet. The study aimed to identify GSB resistant melon germplasm. We screened a total of 60 genotypes including 16 lines and 44 melon cultivars collected from USA and Korea. Among the 16 melon lines, four lines including 'PI482399', 'PI140471', 'PI136170' and 'PI420145', and two Korean cultivars viz. 'Asia Papaya' and 'Supra' showed complete resistance. We were aware that both genotypic and environmental variations could influence the phenotypic screening of resistance and susceptibility. We therefore, further assessed all genotypes using 20 SSR markers. The SSR marker 'CMCT505' linked to Gsb1 in chromosome 1 perfectly grouped resistant and susceptible lines indicating that resistance is probably due to the presence of Gsb1 gene. Cloning and sequencing of resistant and susceptible Gsb1 amplicons showed that there were 32-bp deletions in resistant line and 39-bp deletions in resistant cultivar compared to susceptible one. Thus, the resistant melon lines and cultivars identified in this study could be recommended for the melon breeding program. Furthermore, the SSR marker 'CMCT505' which is tightly linked with Gsb1 could be used for molecular screening of melon germplasm.

• Food Science of Animal Resources
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• v.40 no.3
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• pp.401-414
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• 2020

The emergence and persistence of methicillin-susceptible Staphylococcus aureus (MSSA) and methicillin-resistant S. aureus (MRSA) in livestock animals have been reported as a potential risk factor for transmission to humans. In this study, we investigated the nationwide prevalence and characteristics of MRSA and MSSA in the Korean beef production system, including retail markets, slaughterhouses, and cattle farms. From a total of 1,285 samples, only 5 MRSA strains were isolated: from a farmer (1 ST72 MRSA), a carcass sample from a slaughterhouse (1 ST72 MRSA), and beef cattle (3 ST5 MRSA). In addition, 11 MSSA strains were isolated from beef cattle (n=3), humans (1 farmer, 1 slaughterhouse worker, and 4 retail market workers), and carcass samples (n=1) and slaughterhouse environment (n=1). Although the prevalence of MRSA and MSSA in beef cattle was much lower than that reported in pigs, 5/5 MRSA and 2/11 MSSA strains displayed multiple drug resistance (MDR) phenotypes. Unlike the swine-associated MRSA, no correlation was found between tetracycline/zinc resistance and MDR phenotype. However, MRSA strains had an identical set of staphylococcal enterotoxins and exhibited enhanced levels of resistance to antimicrobial peptides (PMAP-36 and LL-37) compared to the MSSA strains. In conclusion, continued and systemic surveillance of livestock, meat products, and humans in close contact with livestock/meat products is necessary to prevent the transmission of MRSA and MSSA to humans.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.12
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• pp.1830-1836
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• 2003

Studies using natural resistance-associated macrophage protein (NRAMP) identification indicated that cattle could be selected for immunity. Several studies performed on intracellular organisms such as Mycobacterium, Salmonella, Brucella and Leishmania in human and mouse revealed that resistance against these bacteria was dependent on high activity of NRAMP1 in macrophages. However, hardly any researches have been done on Staphylococcus aureus in bovine mastitis, which is an intracellular organism and the main cause of bovine mastitis. The objectives of this study were to establish reverse transcriptase polymerase chain reaction (RT-PCR) methods, through which NRAMP1 mRNA expression could be compared and analyzed between mastitis-resistant and -susceptible cows. NRAMP1 gene and its expression were investigated using 20 cows (Holstein Friesian) in Korea. Cows were evenly split into two groups, with and without histories of clinical mastitis. Equivalent numbers of cows were randomly selected from each group. Monocytes were isolated from the bovine peripheral blood of each selected cows and activated with lipopolysaccharide (LPS). mRNA was separated from the monocytes and cDNA of NRAMP1 was synthesized and amplified using RT-PCR with amplification of $\beta$-actin as a control. The difference in NRAMP1 expressions of mastitis-resistant (n=10) and -susceptible (n=10) Holstein cows was analyzed. Results demonstrate that resistant cows produced more NRAMP1 mRNA than the susceptible ones, and ratios of NRAMP1:$\beta$-actin expression were higher in resistant cows with or without LPS activation. Therefore, this study could be applied to select bovine mastitis resistant cows before infection based on the expression of NRAMP1.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.11
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• pp.6769-6773
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• 2013

Background: Few local studies have explored the process of adverse transition of smoking stages among adolescents. The present investigation aimed to identify adverse transitions prospectively from the early stages till the escalation of the stages after one year. Materials and Methods: Data were collected in two waves from a cohort of 2,552 adolescents aged 12-13 years old studying in 15 secondary schools based in Kinta, Perak. A multistage sampling method was used to select the schools and a self-administered structured questionnaire was applied to help categorize the participants into five different smoking stages. Nonsmokers were divided into never smokers and susceptible never smokers. Ever-smokers were categorized as experimenters, current smokers or ex-smokers. Results: Among the participants 46.8% were Malay, 33.5% Chinese and 17.1% Indians. At baseline, we had 85.3% non-smokers and 14.6% ever smokers. Incidence of adverse transition among all our participants was 24.1%, with a higher value among male participants (16.8%). A higher proportion of susceptible never smokers and experimenters progressed to current smoking stage compared to never smokers. Conclusions: This study highlights the changes and patterns of adverse transition among adolescents. Male adolescents, those who are susceptible to smoking and those who had already tried experimenting with cigarettes have a higher chance of escalating to a higher smoking stage.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.5
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• pp.429-433
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• 2004

A single recessive gene, rxp, controls the bacterial leaf pustule (BLP) resistance in soybean and in our previous article, it has been mapped on linkage group (LG) D2 of molecular genetic map of soybean. A total of 130 recombinant inbred lines (RILs) from a cross between BLP-resistant SS2-2 and BLP-susceptible Jangyeobkong were used to identify molecular markers linked to rxp. Fifteen simple sequence repeat (SSR) markers on LG D2 were screened to construct a genetic map of rxp locus. Only four SSR markers, Satt135, Satt372, Satt448, and Satt486, showed parental polymorphisms. Using these markers, genetic scaffold map was constructed covering 26.2cM. Based on the single analysis of variance, Satt372 among these four SSR markers was the most significantly associated with the resistance to BLP. To develop new amplified fragment length polymorphism (AFLP) marker linked to the resistance gene, bulked segregant analysis (BSA) was employed. Resistance and susceptible bulks were made by pooling equal amount of genomic DNAs from ten of each in the segregating population. A total of 192 primer combinations were used to identify specific bands to the resistance, selecting three putative AFLP markers. These AFLP markers produced the fragment present in SS2-2 and the resistant bulk, and not in Jangyeobkong and the susceptible bulk. Linkage analysis revealed that McctEact97 $(P=0.0004,\;R^2=14.67\%)$ was more significant than Satt372, previously reported as the most closely linked marker.

• The Plant Pathology Journal
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• v.30 no.1
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• pp.75-81
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• 2014

In total, 170 carrot lines developed in Korea were screened for resistance to Meloidogyne incognita race 1 to select parental genetic resources useful for the development of nematode-resistant carrot cultivars. Using the gall index (GI), gall formation was examined on carrot roots inoculated with approximately 1,000 second-stage juveniles of the nematode 7 weeks after inoculation. Sixty-one carrot lines were resistant (GI ${\leq}1.0$), while the other 109 were susceptible (GI > 1.0) with coefficient of variance (CV) of GI for total carrot lines 0.68, indicating low-variation of GI within the lines examined. The histopathological responses of two carrot plants from resistant and susceptible lines were examined after nematode infection. In susceptible carrots, giant cells formed with no discernible necrosis around the infecting nematodes. In the resistant carrot line, however, no giant cells formed, although modified cells were observed with extensive formation of necrotic layers through their middle lamella and around the infecting nematodes. This suggested that these structural modifications were related to hypersensitive responses governed by the expression of true resistance genes. Therefore, the Korean carrot lines resistant to the nematode infection are potential genetic resources for the development of quality carrot cultivars resistant to M. incognita race 1.

• The Plant Pathology Journal
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• v.23 no.3
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• pp.193-202
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• 2007

Typical susceptible symptoms of the bacterial pustule disease caused by Xanthomonas axonopodis pv. glycines are pustule and chlorotic haloes that usually occur in leaves of Glycine max plants. The soybean genotype 'PI96188' showed an atypical response to all tested races X. axonopodis pv. glycines, accompanied with necrosis without chlorotic haloes on the underside of the necrotic symptoms. X. axonopodis pv. glycines 8ra grew to levels from 10 to 100 fold lower on PI96188 than on susceptible cultivar Jinjoo1, but 10-fold higher than on the resistant cultivar CNS. The chlorophyll content in PI96188 leaves remained unchanged until 12 days after bacterial infection. Ultrastructural observation showed that the infected leaf cells of PI96188 had intact normal chloroplasts compared to those of the susceptible cultivar Jinjoo1. Chloroplast degradation or the absence of chloroplasts in cells of the infected tissues was observed in Jinjoo1. Senescence-related ACS7 gene was significantly induced in PI96188 compared to those in Jinjoo1 at 2 days after inoculation. While photosynthesis-related rbcS gene showed the dramatic change in Jinjoo1, this gene was constitutively expressed in PI96188. However, expression of the defense-related genes, such as peroxidase and isoflavone synthase in the infected PI96188 leaves was similar to that in Jinjoo1. Together, these results suggest that the novel necrotic symptom in PI96188 is a kind of resistant response different from a typical hypersensitive response in the resistant genotypes.

• Journal of Environmental Health Sciences
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• v.35 no.4
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• pp.249-258
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• 2009

The objectives of this study were to compare the relative risk of all-cause mortality and cause-specific mortality associated with Asian dust events, and especially to investigate the effects on the susceptible population such as the elderly and children, which were based on the data in Seoul from 2000 to 2006. Both of the study periods with/without Asian dust days, respiratory-cause mortality was the highest, followed by cardiovascular-cause mortality and all-cause mortality in sequence among mortality related to air pollution for all-aged group. As to susceptible group, the relative risk of mortality is the highest for +65 yrs group among all-cause mortality. According to comparison of mortality with/without Asian dust days, the relative risk of all-cause mortality is larger in the model with Asian dust days than the one in the model without Asian dust days among all age group (except for under 15 yrs group) and all air pollutants. The relative risk of cause-specific mortality (except for ozone in under 15 yrs group in case of respiratory-cause mortality, and ozone in all age group and over 65 yrs group in case of cardiovascular-cause mortality) per IQR increase of each pollutant is larger in the model without Asian dust days.

• Journal of Korean Clinical Health Science
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• v.6 no.1
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• pp.1056-1064
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• 2018

Purpose. This study reported on body type perception of people aged ${\geq}19years$, regardless of gender, and on its association with disease morbidity and the quality of life and aimed to observe the effects of stress on body weight perception, disease morbidity, and the quality of life. Methods. The data from 218,899 persons aged ${\geq}19years$ who were respondents to the 2010 Community Health Survey were finally analyzed. A designated program was used to perform complex sample analysis; chi-square test was carried out to determine body type perception by the general characteristics and disease status and analyze health-related behavior and weight control behavior by body type perception, and multiple logistic regression was used to observe the effects of body type perception on mental health and the quality of life. Results. 34.9% of all the respondents misperceived their body type and females were more likely to misperceive their body type. The older they were, the more poorly they perceived their body type; those perceiving their body type poorly were significantly more susceptible to both hypertension and diabetes. When correction was made in relation to gender, age, and so on, those perceiving their body type excessively were more susceptible to hypertension (1.43[1.367-1.050]) and diabetes morbidity (1.36[1.294-1.428]). Body type perception affected the quality of life: the respondents perceiving their body type poorly (0.91[0.884-0.940]) or excessively (0.75[0.720-0.770]) showed lower quality of life than those perceiving their body type correctly. Conclusions. Distorted body type perception affected disease morbidity and the quality of life: the respondents excessively perceiving their body type were significantly more susceptible to both hypertension and diabetes and those perceiving their body type excessively or poorly showed lower quality of life than those perceiving it correctly. It is therefore necessary to make multilateral efforts to cultivate correct body type perception.