• The Plant Pathology Journal
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• 제40권2호
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• pp.160-170
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• 2024

Erwinia amylovora is a plant pathogen that causes fire blight on apples and pears. Bacteriophages, which are viruses that selectively infect specific species of bacteria and are harmless to animal cells, have been considered as biological control agents for the prevention of bacterial pathogens. In this study, we aimed to use bacteriophages that infect E. amylovora as biocontrol agents against fire blight. We isolated bacteriophages Fifi044 and Fifi318 infecting E. amylovora, and characterized their morphology, plaque form, and genetic diversity to use as cocktails for disease control. The stabilities of the two phages were investigated at various temperatures and pH values and under sunlight, and long-term storage experiment was conducted for a year. To evaluate whether the two phages were suitable for use in cocktail form, growth curves of E. amylovora were prepared after treating the bacterial cells with single phages and a phage cocktail. In addition, a disease control test was conducted using immature apples and in vitro cultured apple plantlets to determine the biocontrol effects of the phage cocktail. The two phages were morphologically and genetically different, and highly stable up to 50℃ and pH value from 4 to 10. The phages showed synergistic effect when used as a cocktail in the inhibition of host bacterial growth and the disease control. This study demonstrated that the potential of the phage cocktail as a biocontrol agent for commercial use.

• 한국어병학회지
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• 제24권2호
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• pp.85-93
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• 2011

Edwardsiella tarda (E. tarda)는 담수 및 해수어에 광범위하게 감염을 일으키는 그람 음성 박테리아이다. 본 연구에서는 서해안 넙치 양식장에서 분리한 E. tarda에 대해 특이 용균을 보이는 파아지를 분리하여 파아지의 활성에 미치는 환경적 요인인 pH와 배양 온도의 영향 등을 조사하였다. 또한 어류모델로서는 담수어종인 Nile tilapia (Oreochromis niloticus)를 이용하였으며 E. tarda와 파아지와의 상호작용을 알아보았다. pH 안정성 실험에서는 담수보다 해수에서 높은 활성을 보였으며 온도 안정성 실험 결과 $50^{\circ}C$까지 일정한 활성을 보였다. Tilapia 감염 실험에서는 파아지와 E. tarda를 접종하였다. 그 결과 실험군은 대조군에 비해 24시간째까지 E. tarda수가 일정하게 감소하는 것을 확인하였으며 파아지는 처음 접종 양보다 약간 증폭됨을 알 수 있었다. 본 연구의 결과는 E. tarda에 의해 발생되는 질병을 특이 파아지를 이용하여 제어할 수 있음을 암시해준다.

• 치위생과학회지
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• 제5권4호
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• pp.199-204
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• 2005

51예의 구강 백반증과 149예의 편평태선의 임상적 발현 양상을 비교 분석하고 병리조직 소견에 따른 환자 예후를 추적하여 임상적 병리조직학적 차이점을 고찰하였다. 분석 결과, 연령 분포와 성별, 임상적 특징, 환자의 임상 증상, 상피 이형성 빈도, 임상 추적 관찰 결과 재발 여부 등에 있어 차이를 나타냈다. 구강 백반증과 편평태선의 임상적인 감별점은 구강백반증의 경우 각화증을 유발한 원인, 즉 협점막과 혀의 측면부위에 가해질 수 있는 만성적 자극, 흡연 등의 원인을 제거했을 때 소실되는지의 여부, 편평태선의 경우 전형적으로 양측성 발생과 다발성 병소, 통증이나 압통, 불쾌감과 작열감 등의 증상, 동반되는 피부 병소 등을 들 수 있다. 임상 진단에서 확진을 하지 못하는 경우는 조직 생검을 통하여 최종 진단을 내릴 수 있다.

• 한국약용작물학회지
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• 제10권5호
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• pp.327-332
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• 2002

This study was conducted to investigate the immuno-regulatory effect and apoptosis of L1210 and HL60 leukemia cells of methanol-extracts of Cornus kousa Burg(CKB). The proliferation of mouse splenocytes and thymocytes enhanced by the addition of $10\;{\mu}g/ml$ of CKB. CKB were administered p.o. once a day for 7 days in adult male BALB/c mice. CKB increased the splenic and thymic T lymphocytes, especially the number of $T_H$ cells markedly increased by the treatment of CKB. CKB treatment induced the apoptotic cell death in L1210 mouse leukemia and HL60 human leukemia cells. In addition, CKB also accelerated the phagocytic activity in peritoneal macrophages and increased the production of plaque forming cells. These results suggest that CKB have an various immuno-regulatory property.

• 생명과학회지
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• 제10권4호
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• pp.368-373
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• 2000

Enteroviruses in the environment pose a public health risk because they can be transmitted via the fecal-oral route through contaminated water, and low numbers are able to initiate an infection in humans. Because the levels of viruses typically found in environmental water and drinking water are low, they must be concentrated from hundreds to thousands of liters of water. Therefore, the main goal of this study was the development of a rapid, simple and efficient procedure to concentrate, isolate and detect enteroviruses from environmental water samples. Viruses were first concentrated by adsorption to 1 MDS cartridge filter and then eluted with approximately 0.5 liter of 1.5% beef extract/0.05M glycin(pH 9.4). In this study, several procedures to concentrate and purify intact viruses from beef extract obtained from the adsorbent filters were tested. Among them, organic floccuration was the best reliable method for reconcentration. sample volume could be reduced to 200∼400 folds and the efficiency of virus recovery through the procedure was over 72%. Finally, the samples were filtered through a membrane disk filter and then analyzed by either the plaque assay or combined cell culture-polymerase chain reaction.

• 고려인삼학회:학술대회논문집
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• 고려인삼학회 1984년도 학술대회지
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• pp.225-232
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• 1984

인삼은 외적 유해인자에 대한 비특이적 생체 저항력을 증진시켜주며 물리적, 화학적, 생물학적인 외적 변화에 대해 adaptogen으로서 작용한다. 인삼은 말초혈액 림파구에 의한 면역 인터페론 합성을 촉진시키며, 바이러스에 감염된 흰쥐에 대해 치료효과가 뚜렷하다. 인삼을 Semliki forest virus(SFV) 감염전후 계속 경구투여하면 $34{\~}40\%$의 보호 효과가 있었다. 인삼투여로 세포의 항체생성능이 증가되었으며, sheep의 적혈구 세포에 대한 혈행항체의 역가가 증진되었다. 또한 SFV 항원에 대한 면역성도 높아졌으며, N.K. 세포의 활성도도 크게 증가되었다. Aspergillus Ochraceus ATCC 28706 균주에서 추출한 6-MFA는 인터페론 유도물질 (inducer)로서 잘 알려져 있으며 두 종류의 인터페론, 즉 산성 용액에서 안정한 인터페론과 불안정한 인터페론을 유도시킨다. 인삼은 이들 두 종류의 인터페론 생성을 모두 증진시킨다. 동물실험 결과 6-MFA를 단독 처리하면 SFV 감염에 의해 낮은 보호작용을 보이나, 인삼투여를 병용하면 SFV 감염을 $100{\%}$ 완전히 방지할 수 있었다.

• 대한미생물학회지
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• 제22권2호
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• pp.117-123
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• 1987

Previous studies have been performed for the sero-identification of selected species of Bacteroides by immunofluorescence antibody techniques and enzyme-linked immunosorbent assay using species-specific rabbit antisera to B. gingivalis, B. intermedius, and B. melaninogenicus. However, these studies have not commented on the serological cross-reactivity between these 3 species of black- pigmented Bacteroides. For the cross-reactivity study, antisera to B. gingivalis ATCC 33277, B. intermedius ATC C25261 and B. asaccharolyticus ATCC 25260 were raised from rabbits. Preliminary study for observing the cross-reactivity between these species was performed by indirect immunoflourescence technique. Immunoabsorption of the antisera was done with bacterial cells from the other species and the species-specificity of the antisera was conformed by the absence of reactivity with bacterial strains from the other species by indirect immunofluorescence technique and enzyme-linked immunosorbent assay. Three representative unabsorbed antisera cross-reacted strongly with cells from the other species. Especially, anti-B. asaccharolyticus ATCC 25260 antiserum showed a strong cross-reactivity with B. gingivalis ATCC33277. After immunoabsorption of 3 representative antisera with the other species, the cross-reactivity was found only between B. gingivalis ATCC 33277 and B. asaccharolyticus ATCC 25260. Further study would be necessary to clarify the cross-reactivity between important oral black-pigmented Bacteroides from subgingival plaque or bacterial colonies for rapid identification.

• 한국치위생학회지
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• 제8권1호
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• pp.133-146
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• 2008

Purpose: This research aims to investigate into company workers' awareness of scaling and related factors and provide basic materials for setting up appropriate policies to improve the hygiene of the mouth of industrial workers and developing training programs for the worker's hygiene of their mouth, as part of researches to establish schemes for improving the workers's hygiene of their mouth. Method: Questionnaire was conducted by convenience sampling for 220 office workers belonging to H Group located in Seoul Metropolitan city over about 5 weeks between December 17, 2007 and January 20, 2008. The questionnaire for this study was constructed in consideration of general characteristics of the subjects, behaviors of the dental management. and scaling. The collected questionnaires were electronically processed using SPSS 12.0. Result: The followings are the findings of this research. First, in general, scaling is experienced by male unmarried worker in their 40s. whose monthly average income is 1.00-1.99 million won and have little interest in the hygiene of their mouth and, consequently. whose hygiene of the mouth is not good. Second, scaling is experienced once every six months by the worker in their 50s or older, who are college graduates and have much interest in the hygiene of their mouth and, consequently. whose hygiene of the mouth is good. Third. scaling is not periodically conducted because of high costs of it in terms of almost every parameter of general characteristics. Fourth, they have correct knowledge of scaling since they regard it as 'removing of plaque and tartar' in terms of every parameter of general characteristics. Fifth, the workers' sex (pE0.05), hygienic condition of the mouth (pE0.05) and knowledge of scaling (pE0.001) have a significant effect on their scaling experience. Conclusion: It is considered that dental health management should be continued by training of the importance of prevention through scaling as measure for dental health promotion of workers.

• 대한미생물학회지
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• 제35권1호
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• pp.1-8
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• 2000

In order to explore the potential of ascorbic acid supplementation for the prevention and treatment of herpes simplex viral diseases, plaque reduction assays were performed. Ascorbic acid as well as copper chloride/ferric chloride were added to wells containing Vero cells infected with herpes simplex virus type 1 (HSV-1), and the infectivity of HSV-1 was determined. Since copper and iron are major transition metals in human plasma, near the normal human plasma concentrations of them were used for experiments. When Cu(II) and Fe(III) were applied, there were no significant differences between virus control and Cu(II)/Fe(III)-treated groups. But, when appropriate concentrations of ascorbic acid were added to wells, meaningful differences between control and ascorbate-treated groups were found. In the presence of Cu(II)/Fe(III) at $5.8/3.7\;{\mu}M$, 72-h treatment with ascorbate at $50\;{\mu}M$ reduced HSV-1 infections to $10.77%{\pm}4.25%$ (P < 0.001) and $500\;{\mu}M$ did to $3.06%{\pm}1.62%$ (P < 0.001). Moreover, the cytotoxicities for Vero cells at those concentrations were insignificant (P > 0.05). Current recommended dietary allowance (RDA) of ascorbic acid is 60 mg/day, and the oral intake of 60 mg/day of ascorbic acid yields plasma ascorbic acid at 45 to $58\;{\mu}M$ in a healthy adult man. Therefore, the results of this study suggest that the maintenance of appropriate level (more than $50\;{\mu}M$) of ascorbic acid in human plasma by appropriate amount (more than the RDA) of ascorbic acid supplementation may be helpful for the prevention and treatment of diseases caused by HSV -1 in an adult man. In addition, this study also suggests that ascorbic acid may be useful for the prophylaxis of fatal HSV-1 infections in neonates and the prevention of HSV-1 reactivation in immunocompromised hosts.

• 한국미생물·생명공학회지
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• 제37권1호
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• pp.33-41
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• 2009

알래스카산 낙엽진흙버섯[Porodaedalea pini (Brot.) Murrill] (syn. Phellinus pini)의 자실체 조분쇄물로부터 $100^{\circ}C$에서 4시간 추출하여 건량 수율 20.5%의 건조 분말 열수추출물을 제조하여, HeLa 세포에서 CVB3에 대한 항바이러스 활성을 조사한 결과 plaque 형성을 현저히 억제하였다. 또한, 다른 여러 가지 버섯 추출물에 비해 neuraminidase 활성 저해능이 가장 높았다. 열수 추출물로부터 75% 에탄올 침전으로 건량 수율 28.3%의 저분자 상등액 건조물(ES)과 수율 43.3%의 고분자 침전물 건조물(EP)을 얻었다. 상등액인 ES에서는 항바이러스 활성이 없었지만, 침전물인 EP는 HeLa 세포에서 CVB3바이러스에 대해 농도 의존적으로 plaque 형성을 현저히 억제하였고, $EC_{50}$은 0.45 mg/mL 이었으며, HeLa 세포에 대한 세포독성 $CC_{50}$은 2.25mg/mL 이었다. 또한, EP는 neureminidase 활성을 농도 의존적으로 저해하였으며, 1.7mg/mL에서 약 75%의 효소활성 억제효과를 보였다. 이러한 결과는 낙엽진흙버섯 자실체의 별수추출물로부터 얻어진 에탄을 침전물 EP가 CVB3 뿐만 아니라, influenza virus(Flu)등에 대해서도 광범위하게 항바이러스 활성을 나타낼 가능성을 보여 주었다. EP는 다당류로서 glucose의 함량이 79.8%로 가장 높았고 galactose, xylose, mannose와 fucose를 소량 포함한 수용성 heteroglycan의 일종으로, 소량(12.7%, w/w)의 단백질 또는 작은 펩타이드를 함유한 당단백의 일종일 것으로 사료된다.