• 식물병연구
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• 제29권2호
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• pp.137-144
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• 2023

Exserohilum turcicum is a fungus that causes northern corn leaf blight (NCLB) and has deleterious effects on maize production globally. Therefore, it is prudent to mitigate the effects of NCLB using genetic diversity. The objective of this research was to assess the severity of NCLB disease on the growth and yield of various maize genotypes. A randomized complete block design field experiment, replicated three times, was conducted to evaluate the effect of E. turcicum on 10 maize hybrids. Percent disease index, plant height, and leaf area were recorded at the silk stage. Cob weight, grain fresh weight, and grain yields were determined at harvest maturity. All measured parameters were significantly different (P<0.05) between the maize hybrids. Of the 10 genotypes, four (PAN 4R-528R, PAN 4R-728BR, PAN 3R-724BR, and P1788BR) were susceptible, five (DKC74-74BR, PAN 5R-582R, PAN 5R-890R, PAN 5R-854R, and PAN 5R-590R) were moderately susceptible, and one (DKC80-40BR) was moderately resistant. DKC80-40BR exhibited greater cob weight, while DKC74-74BR was superior in all other plant growth and yield components. Interestingly, although not significant (P>0.05) and high, maize growth and yield parameters had negative correlations with disease incidence, except for grain fresh weight. Therefore, DKC80-40BR may be selected for cultivation in areas prone to NCLB to reduce maize susceptibility to the disease, while DKC74-74BR may improve crop performance. These hybrids could be considered as potential sources of resistance or tolerance to NCLB for further validation by plant breeders.

• 한국미생물·생명공학회지
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• 제46권2호
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• pp.162-170
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• 2018

Non-typhoidal Salmonella is one of the main pathogens causing food-borne illness in humans, with up to 20% of cases resulting from consumption of pork products. Over the gastroenteritis signs, multidrug resistant Salmonella has arisen. In this study, pan-susceptible phenotypic strains of Salmonella enterica serotype Weltevreden recovered from pig production chain in Chiang Mai, Thailand during 2012-2014 were chosen for analysis. The aim of this study was to use whole genome sequencing (WGS) data with an emphasis on antimicrobial resistance gene investigation to assess their pathogenic potential and genetic diversity determination based on whole genome Multilocus Sequence Typing (wgMLST) to expand epidemiological knowledge and to provide additional guidance for disease control. Analyis using ResFinder 3.0 for WGS database tracing found that one of pan-susceptible phenotypic strain carried five classes of resistance genes: aminoglycoside, beta-lactam, phenicol, sulfonamide, and tetracycline associated genes. Twenty four and 36 loci differences were detected by core genome Multilocus Sequence Typing (cgMLST) and pan genome Multilocus Sequence Typing (pgMLST), respectively, in two matching strains (44/13 vs A543057 and A543056 vs 204/13) initially assigned by conventional MLST and Pulsed-field Gel Electrophoresis (PFGE). One hundread percent discriminant ability can be achieved using the wgMLST technique. WGS is currently the ultimate molecular technique for various in-depth studies. As the findings stated above, a new of "gold standard typing method era" for routine works in genome study is being set.

• Parasites, Hosts and Diseases
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• 제51권3호
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• pp.289-295
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• 2013

Different functions have been attributed to $CD4^+CD25^+Foxp3^+$ regulatory T-cells (Tregs) during malaria infection. Herein, we describe the disparity in Treg response and pro- and anti-inflammatory cytokines during infection with Plasmodium berghei ANKA between young (3-week-old) and middle-aged (8-month-old) C57BL/6 mice. Young mice were susceptible to cerebral malaria (CM), while the middle-aged mice were resistant to CM and succumbed to hyperparasitemia and severe anemia. The levels of pro-inflammatory cytokines, such as TNF-${\alpha}$, in young CM-susceptible mice were markedly higher than in middle-aged CM-resistant mice. An increased absolute number of Tregs 3-5 days post-inoculation, co-occurring with elevated IL-10 levels, was observed in middle-aged CM-resistant mice but not in young CM-susceptible mice. Our findings suggest that Treg proliferation might be associated with the suppression of excessive pro-inflammatory Th1 response during early malaria infection, leading to resistance to CM in the middle-aged mice, possibly in an IL-10-dependent manner.

• 한국식품조리과학회지
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• 제31권1호
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• pp.62-71
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• 2015

The purpose of this study was to evaluate the changes on the characteristics of the oxidative stability of Tenebrio molitor larvae during cold storage at $4^{\circ}C$. Pretreatment for T. molitor larvae was designed into three methods: raw (R), freeze-dried (F.D.), and pan-fried (P.F.). The water content of the raw sample (61.46%) was higher than those of other samples (F.D.: 5.02%, P.F.: 3.67%) and its high water content was expected to facilitate the oxidation of the raw sample. In our results, the peroxide value and the carbonyl value of all of the samples increased and the raw sample, after storage for 18 day, showed the highest value. The pan-fried sample had no significant increase in its lactic acid content, acid value, and thiobarbituric acid value; whereas those values were increased in the raw sample and the freeze-dried sample (p<0.05). The browning reaction was more progressed in the pan-fried sample than other samples at 0 day, but there was no significant change during the storage. The raw sample and the freeze-dried sample had their browning indexes increase with the increasing storage period (p<0.05). The pan-fried sample produced less oxidation products than the freeze-dried sample, indicating that the unheated sample was more susceptible to oxidation than the heated samples. In conclusion, heating treatment and low water content would be effective for improving the safety and stability of T. molitor larvae during cold storage.

• The Plant Pathology Journal
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• 제37권4호
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• pp.375-388
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• 2021

Rice yellow mottle virus (RYMV) is the most harmful virus that affects irrigated and lowland rice in Africa. The RBe24 isolate of the virus is the most pathogenic strain in Benin. A total of 79 genotypes including susceptible IR64 (Oryza sativa) and the resistant TOG5681 (O. glaberrima) as checks were screened for their reactions to RBe24 isolate of RYMV and the effects of silicon on the response of host plants to the virus investigated. The experiment was a three-factor factorial consisting of genotypes, inoculation level (inoculated vs. non-inoculated), and silicon dose (0, 5, and 10 g/plant) applied as CaSiO₃ with two replications and carried out twice in the screen house. Significant differences were observed among the rice genotypes. Fifteen highly resistant and eight resistant genotypes were identified, and these were mainly O. glaberrima. Silicon application did not affect disease incidence and severity at 21 and 42 days after inoculation (DAI); it, however, significantly increased plant height of inoculated (3.6% for 5 g CaSiO₃/plant and 6.3% for 10 g CaSiO₃/plant) and non-inoculated (1.9% for 5 g CaSiO₃/plant and 4.9% for 10 g CaSiO₃/plant) plants at 42 DAI, with a reduction in the number of tillers (12.3% for both 5 and 10 g CaSiO₃/plant) and leaves (26.8% for 5 g CaSiO₃/plant and 28% for 10 g CaSiO₃/plant) under both inoculation treatments. Our results confirm O. glaberrima germplasm as an important source of resistance to RYMV, and critical in developing a comprehensive strategy for the control of RYMV in West Africa.

• 한국환경보건학회지
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• 제35권6호
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• pp.433-446
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• 2009

Pharmaceuticals in the aquatic environment are trace contaminants of growing importance in environmental health due to their physiologically active nature. Pharmaceuticals could affect non-target species and might eventually damage sustainability of susceptible populations in the ecosystem. Potentials for health consequences among susceptible human population cannot be ruled out since long-term exposure to cocktails of pharmaceuticals, which might be present in drinking water, is possible. Selection of antibiotic resistant microorganisms is of another concern. In order to understand, and if needed, to properly address the environmental health issues of pharmaceutical residues, knowledge gaps need to be filled. Knowledge gaps exist in many important areas such as prioritization of target pharmaceuticals for further risk studies, occurrence patterns in different environments, chronic toxicities, and toxicities of pharmaceutical mixtures. Appropriate treatment technologies for drinking water and wastewater could be developed when they are deemed necessary. One of the simplest, yet most efficient measures that could be undertaken is to implement a return program for unused or expired drugs. In addition, implementation of environmental risk assessment frameworks for pharmaceuticals would make it possible to efficiently manage potential environmental health problems associated with pharmaceutical residues in the environment.

• 한국환경과학회지
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• 제29권1호
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• pp.109-117
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• 2020

Asthmatics are more susceptible to fine particulate matters (PM_2.5), compared to the general population. It has been reported that indoor PM_2.5 is mainly generated by combustion of fossil fuels, meat or fish In particular, asthmatics are known to be more susceptible to indoor PM_2.5 because 65~95% of child or adult asthmatics stay inside the house. Thus, understanding the association between indoor activity patterns and variations in indoor PM_2.5 levels is important. The purpose of this study is to determine the distribution of hourly indoor PM_2.5 concentrations in asthmatics' homes, and to evaluate its association with pan-frying cooking activity patterns, the most common PM_2.5 emission related activity. From November 2017 to February 2018, real-time PM_2.5 concentrations were measured in the living room of each asthmatic's house (n = 35) for three weeks at 1 minute intervals. At the same time, self-reported daily activity patterns, hourly proportion (%) of cooking activities, were also recorded every hour over three weeks for each patient. In this study, we provided quantitative evidence that the distribution patterns of indoor hourly PM_2.5 concentrations were associated with indoor cooking activities, especially in the homes of adult asthmatics. In addition, we observed that PM_2.5 emitted by pan-frying could maintain even over up to 2 hour lagtime.

• Journal of Information Processing Systems
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• 제15권4호
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• pp.853-864
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• 2019

Microblogging services (such as Twitter) are the representative information communication networks during the Web 2.0 era, which have gained remarkable popularity. Weibo has become a popular platform for information dissemination in online social networks due to its large number of users. In this study, a microblog information dissemination model is presented. Related concepts are introduced and analyzed based on the dynamic model of infectious disease, and new influencing factors are proposed to improve the susceptible-infective-removal (SIR) information dissemination model. Correlation analysis is conducted on the existing information dissemination risk and the rumor dissemination model of microblog. In this study, web hyper is used to model rumor dissemination. Finally, the experimental results illustrate the effectiveness of the method in reducing the rumor dissemination of microblogs.

• Journal of Microbiology
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• 제45권4호
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• pp.358-363
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• 2007

Multi-drug resistant Pseudomonas aeruginosa has been implicated in a variety of serious therapeutic problems in clinical environments. Among the 968 P. aeruginosa isolates obtained from two hospitals in Daegu, Korea, we acquired 17 isolates that were resistant to all available tested antimicrobial agents, with the exception of colistin (colistin-only sensitive). We characterized the antimicrobial susceptibilities, $metallo-{\beta}-lactamases$, and epidemiological relatedness among the colistin-only sensitive P. aeruginosa isolates. All colistin-only sensitive isolates were positive in the modified Hodge test and imipenem-EDTA synergy test, thereby indicating the production of $metallo-{\beta}-lactamases$. 11 isolates from the secondary hospital and six isolates from the tertiary teaching hospital harbored $bla_{VIM-2}$ and $bla_{IMP-1}$, respectively. The pulsed-field gel electrophoretic analysis of the SpeI-digested DNA from P. aeruginosa isolates indicated that two different clones of colistin-only sensitive P. aeruginosa originated from each hospital, and had spread within the hospital environment. Overall, colistin-only sensitive P. aeruginosa was detected in Korea for the first time, but no pan-drug resistant bacteria were identified. Nationwide surveillance is required in order to monitor the emergence of colistin-only sensitive or pan-drug resistant bacteria.

• Tuberculosis and Respiratory Diseases
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• 제59권3호
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• pp.257-265
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• 2005

연구 배경 : 리팜핀 내성 균주에서 리파부틴 약제의 교차 내성정도와 리팜핀 내성-리파부틴 감수성 결핵균의 rpoB 유전자 돌연변이의 특성을 알아보고자 연구를 실시하였다. 연구 방법 : 감수성검사에서 리팜핀에 내성인 균주를 선정하여 리파부틴 농도 $0-80{\mu}g/ml$ 농도로 재접종하여 감수성 여부를 확인하였다. 리팜핀-내성균주 모두 염기서열 분석을 통하여 리파부틴 감수성과의 관계를 조사하였다. 역교잡 방법으로 리파부틴 감수성균을 구별하였다. 연구 결과 : 우리나라에서 분리된 리팜핀 내성인 201균주 중에서 41균주(20.4%)는 리파부틴에 감수성을 보였다. 리파부틴 감수성을 보이는 rpoB 유전자 돌연변이는 Leu511Pro, Ser512Arg, Gln513Glu, Asp516Ala, Asp516Gly, Asp516Val, Asp516Tyr, Ser522Leu, His526Asn, His526Leu, His526Cys, Arg529Pro, Leu533Pro 등 이었다. 역교잡 방법을 이용하였을 경우 rpoB 돌연변이를 가진 균주 중에서 리파부틴 감수성균의 민감도는 92.5%이었고, 특이도는 96.1%이었다. 결 론 : 리팜핀 내성균이라도 약 20.4% (95% 신뢰구간: 14.8% to 26.0%)가 리파부틴 약제에 감수성이므로, 우리나라의 다제내성 결핵환자의 치료에서도 리파부틴이 중요한 약제로서 역할을 할 수 있음이 밝혀졌다. 향후 다제내성 결핵 환자에서의 리파부틴의 치료 효과에 대한 임상적 연구가 필요하다.