• 식물병연구
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• 제27권3호
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• pp.91-98
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• 2021

The current social demand for organic, sustainable, and eco-friendly approaches for farming, while ensuring the health and productivity of crops is increasing rapidly. Biocontrol agents are applied to crops to ensure biological control of plant pathogens. Research on the biological control of white root rot disease caused by a soil-borne pathogen, Rosellinia necatrix, is limited in pears compared to that in apple and avocado. This pathogenic fungus has an extensive host range, and symptoms of this disease include rotting of roots, yellowing and falling of leaves, wilting, and finally tree death. The severity of the disease caused by R. necatrix, makes it the most harmful fungal pathogen infecting the economical fruit tree species, such as pears, and is one of the main limiting factors in pear farming, with devastating effects on plant health and yield. In addition to agronomic and cultural practices, growers use chemical treatments to control the disease. However, rising public concern about environmental pollution and harmful effects of chemicals in humans and animals has facilitated the search for novel and environmentally friendly disease control methods. This review will briefly summarize the current status of biocontrol agents, ecofriendly methods, and possible approaches to control disease in pear orchards.

• 한국수산과학회지
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• 제54권5호
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• pp.585-595
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• 2021

Even though most of aquatic animal pathogens are considered opportunistic and many pose a low direct risk to personnel, all personnel working with aquatic pathogens and facilities using these organisms must comply with the regulation to prevent the release of the pathogen into the environment and causing disease in aquatic animals. First of all, in order to establish a biosafety system for aquatic pathogen, the list of microorganisms that can infect aquatic animals and humans should be drawn up according to the microorganisms encountered within national boundaries. Second, risk assessment guideline for diseases of livestock and aquatic environment is desperately needed. Third, microorganisms should be classified into risk group based on their potential impact on human and aquatic environment. Fourth, facilities handling aquatic pathogens should ensure that these pathogens are securely contained and safely handled for experimental or commercial development purposes. In conclusion, classification is based on the pathogenicity, mode of transmission and host range of the aquatic microorganisms, availability of effective preventative measures and treatments. Furthermore, risk group of aquatic pathogens should be correlated with physical containment facility requirements according to domestic characteristics.

• Mycobiology
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• 제49권2호
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• pp.173-182
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• 2021

Recently, Cryptococcus pseudolongus has been reported as a new pathogen of shiitake (Lentinula edodes). However, its pathological properties are not much known. To further understand its impact on the mushroom, we investigated the pathogen's interactions with the mycelium of shiitake, histopathological properties, host range, and sensitivity to diverse antifungal agents. The strain C. pseudolongus DUCC 4014 inhibited the mycelial growth of L. edodes strain (cultivar Sanjo 701ho) and caused browning in the mycelia confronted with the yeast on PDA. Spray inoculation of the yeast caused an abnormal browning symptom on the cap and/or gills of three shiitake cultivars grown on sawdust media in vinyl bags. Scanning electron microscopic images of the abnormally browned parts of shiitake fruit body illustrated that mushroom tissues were loosed and dispersed in the middle and edge of the cap and the arrangement of basidiospores borne on basidia in the gills was disturbed compared to those of normal shiitake fruit body. Spray inoculation also led to developing abnormal browning on the harvested fruit body, indicating C. pseudolongus could be a problem during mushroom storage. But the yeast was not able to induce abnormal browning on mushrooms of Pleurotus ferulae, Pleurotus fostreatus, and Agaricus bisporus. But it induced browning only on button mushroom (A. bisporus) when they were inoculated after wounding. Tests with 16 kinds of fungicides revealed that the cell growth of C. pseudolongus could be inhibited by benzalkonium chloride at MIC 7 ㎍/ml and benomyl at MIC 3 ㎍/ml.

• 한국미생물·생명공학회지
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• 제50권4호
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• pp.457-464
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• 2022

A public health concern emerging from a zoonotic disease. Monkeypox is caused by the orthopoxvirus specie Monkeypox virus (MPXV). Monkeypox was identified as the most common orthopoxvirus infection in humans following the eradication of smallpox. Monkeypox has a similar clinical presentation to smallpox. The MPXV is now considered a high-threat pathogen that causes a serious public-health problem. The continuous spread of Monkeypox virus from West Africa to all other places around the world throughout 2018 to 2022, have raised concerns that MPXV could have emerged to acquire the immunological and ecological niche vacated by smallpox virus. This review highlights the current knowledge about Monkeypox evolution, infection biology, and epidemiology around the world since from 1970 to 2022, with a focus on the human, viral, and cellular factors that influence virus emergence, infection, spread, and maintenance in nature. This paper also discusses the current therapeutic options for Monkeypox treatment and control. Under the right conditions, with limited smallpox vaccination and very little orthopoxvirus immunity in some areas of the world, MPXV could become a more efficient human pathogen. Finally, the review identified knowledge gaps, particularly in terms of identifying a definitive reservoir host for monkeypox and proposes future research endeavors to address the unanswered questions.

• 생명과학회지
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• 제21권2호
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• pp.227-234
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• 2011

Pseudomonas syringae pv. tabaci는 숙주인 담배에 감염하여 들불병(wild fire)을 일으키는 식물 병원성 세균이다. 이 세균의 pathogenicity island (PAI)는 Type III secretion system 및 병원성 유전자들을 암호화하고 있으며, 병원성 조절에 있어 핵심적인 역할을 한다. 최근 식물 병원성 세균인 Ralstonia solanacearum에서 식물 세포 접촉을 매개로 하여 hrp gene cluster를 양성조절하는 PrhA (plant regulator of hrp) receptor가 발견되었다. 본 연구에서는 P. syringae에서 식물세포에 의해 hrp 유전자가 유도되는지 확인하기 위해, prhA 유사체를 동정하고 PrhA 결실돌연변이주(BL11)를 구축하였다. BL11은 숙주 감염 실험에서 병원성이 현저히 감소하였고, 식물 세포현탁액에서 hrpA 유전자의 발현수준이 hrp 유도배지에서 보다 3배 더 높게 나타났다. 이러한 결과들을 근거로 PrhA가 식물세포접촉에 의한 조절에 중요한 역할을 한다는 것을 확인하였으며, hrpA-gfp reporter fusion을 사용하여 이를 다시 검증하였다.

• Tuberculosis and Respiratory Diseases
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• 제76권5호
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• pp.245-248
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• 2014

Miliary tuberculosis (TB) is a rare extrapulmonary form of TB, and there have been only two reports of miliary TB associated with infection with multidrug-resistant (MDR)-TB pathogen in an immunocompetent host. A 32-year-old woman was referred to our hospital because of abnormal findings on chest X-ray. The patient was diagnosed with MDR-TB by a line probe assay and was administered proper antituberculous drugs. After eight weeks, a solid-media drug sensitivity test revealed that the pathogen was resistant to ethambutol and streptomycin in addition to isoniazid and rifampicin. The patient was then treated with effective antituberculous drugs without delay after diagnosis of MDR-TB. To the best of our knowledge, this is the first case of miliary TB caused by MDR-TB pathogen in Korea.

• The Plant Pathology Journal
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• 제35권6호
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• pp.575-584
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• 2019

Colletotrichum acutatum is a species complex responsible for anthracnose disease in a wide range of host plants. Strain C. acutatum KC05, which was previously isolated from an infected pepper in Gangwon Province of South Korea, was reidentified as C. scovillei using combined sequence analyses of multiple genes. As a prerequisite for understanding the pathogenic development of the pepper anthracnose pathogen, we optimized the transformation system of C. scovillei KC05. Protoplast generation from young hyphae of KC05 was optimal in an enzymatic digestion using a combined treatment of 2% lysing enzyme and 0.8% driselase in 1 M NH₄Cl for 3 h incubation. Prolonged incubation for more than 3 h decreased protoplast yields. Protoplast growth of KC05 was completely inhibited for 4 days on regeneration media containing 200 ㎍/ml hygromycin B, indicating the viability of this antibiotic as a selection marker. To evaluate transformation efficiency, we tested polyethylene glycol-mediated protoplast transformation of KC05 using 19 different loci found throughout 10 (of 27) scaffolds, covering approximately 84.1% of the entire genome. PCR screening showed that the average transformation efficiency was about 17.1% per 100 colonies. Southern blot analyses revealed that at least one transformant per locus had single copy integration of PCR-screened positive transformants. Our results provide valuable information for a functional genomics approach to the pepper anthracnose pathogen C. scovillei.

• The Plant Pathology Journal
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• 제36권6호
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• pp.618-627
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• 2020

Although limited progress have been made about pathogen system of Hibiscus rosa-sinensis and Hibiscus latent Fort Pierce virus (HLFPV), interaction between plant host and pathogen remain largely unknown, which led to deficiency of effective measures to control disease of hibiscus plants caused by HLFPV. In this study, infection of HLFPV in Hibiscus rosa-sinensis was firstly confirmed for the first time by traditional electron microscopy, modern reverse transcription polymerase chain reaction and RNA-seq methods in China (HLFPV-Ch). Sequence properties analyzing suggested that the full-length sequences (6,465 nt) of HLFPV-Ch had a high sequence identity and a similar genomic structure with other tobamoviruses. It includes a 5'-terminal untranslated region (UTR), followed by four open reading frames encoding for a 128.5-kDa replicase, a 186.5-kDa polymerase, a 31-kDa movement protein, 17.6-kDa coat protein, and the last a 3'-terminal UTR. Furthermore, HLFPV-Ch-derived virus-derived siRNAs (vsiRNAs) ant its putative target genes, reported also for the first time, were identified and characterized from disease Hibiscus rosa-sinensis through sRNA-seq and Patmatch server to investigate the interaction in this pathogen systems. HLFPV-Ch-derived vsiRNAs demonstrated several general and specific characteristics. Gene Ontology classification revealed predicted target genes by vsiRNAs are involved in abroad range of cellular component, molecular function and biological processes. Taken together, for first time, our results certified the HLFPV infection in China and provide an insight into interaction between HLFPV and Hibiscus rosa-sinensis.

• 식물병연구
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• 제25권1호
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• pp.1-7
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• 2019

벼도열병균은 벼를 재배하는 모든 지역에서 경제적으로 매우 중요한 병이다. 또한, 벼도열병균은 기주인 벼와 유전자 대유전자설이 적용되는 대표적인 식물병원균 모델이다. 재배지에 도입된 새로운 저항성 벼 품종의 빠른 저항성 상실은 병원균 집단의 레이스 변이가 주요 메커니즘으로 제안되고 있다. 이러한 새로운 레이스 변이는 저항성 유전자에 대항하는 비병원성 유전자의 변이에 의해 나타날 수 있는데, (i) 점돌연변이, (ii) 전이인자(transposon)의 삽입, (iii) frame shift등이 그 대표적인 예라고 할 수 있다. 비병원성 유전자 AVR-Pita1은 이러한 다양한 변이의 원인들이 모두 보고된 대표적인 비병원성 유전자이다. 이 총설에서는 비병원성 유전자 AVR-Pita1에 관한 다양한 정보를 제시하고, 상동성 유전자들인 AVR-Pita2 및 AVR-Pita3 유전자를 정리하였다. 이와 함께, 변이의 원인이 되는 다양한 예제를 리뷰 하였다.

• 대한방사선기술학회지:방사선기술과학
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• 제45권3호
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• pp.233-239
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• 2022

In the radiology department, where radiation is used in medical institutions to perform examinations with various equipment, the field of surgical treatment is the intervention angiography room. Accordingly, strict infection control is required. The purpose of this study was to determine the contamination status by detecting pathogens before and after disinfection in the intervention angiography room, and to determine the degree of death by using a disinfectant, sodium dichloride isocyanurate, which is mainly used in the intervention angiography room. The subjects were 10 medical institutions of general hospital level or higher with an intervention angiography room in the P city, and 12 places with high contact frequency during examinations and procedures were sampled and requested to an analysis institution. As for the sample collection method, up/down, left/right directions were used to increase precision. Before disinfection, all procedures were completed, and after disinfection, exposure was performed using a disinfectant for at least 10 minutes, and detection was performed using a transport medium. As a result, in the pathogen analysis, most pathogens were detected in a humid environment or in a place with high contact frequency for microorganisms to thrive. The detected pathogens were found in the general environment or were human flora. It is a pathogen that does not cause disease under normal healthy host conditions. However, it was found to be an opportunistic infection that causes opportunistic infection depending on the case or situation in which the body's resistance is weakened. In addition, as a result of using the disinfectant mainly used in the intervention angiography room, it was found that more than 93.3% of them died. Therefore, the data of this study will be used as good basic data for the evaluation of pathogens in the intervention angiography room and will be of great help in infection control.