• Journal of Practical Agriculture & Fisheries Research
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• v.25 no.3
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• pp.14-18
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• 2023

White leg shrimps cultured in an inland private aquaculture farm with low salinity waters showed abnormal swimming behavior and appetite reduction in July 2022. Then, gradual mortality was observed in the aquaculture farm. During the diagnosis, bacterial strain KNUAF-SHP3 was isolated from the hepatopancreas of the dead shrimps. Based on the sequence of 16S rRNA gene, KNUAF-SHP3 was proved to be Shewanella sp., clustering into a group with S. algae MARS 14 and S. chilikensis JC5T. According to the result of experimental infection test, all shrimps challenged with high concentrations, 2.1×108 CFU/ml and 2.1×109 CFU/ml showed apparent disease symptoms and the cumulative mortality rates reached 100% in 7 days post challenge. These results emphasized that Shewanella isolate in this study can be a potential pathogen of white leg shrimp cultured in low salinity water.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.9
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• pp.1045-1052
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• 2017

In this study, a battery of genetic-toxicity studies on corn silk extract with high maysin content were performed according to internationally accepted protocols. In a mutation test using Salmonella Typhimurium TA1535, TA1537, TA98, and TA100, the number of mutant colonies did not significantly increase up to a maximum concentration of $5,000{\mu}g/plate$ in the presence or absence of the S9 metabolic activation system. In the chromosome aberration test using Chinese hamster lung fibroblasts, negative results were observed in the concentration up to $1,250{\mu}g/mL$ of corn silk extract. In the micronucleus test using ICR mice, incidence of polymorphonuclear erythrocytes with a maximum concentration of 2,000 mg/kg corn silk extract did not show any significant difference compared to the negative control group. Based on these results, the test substance, con silk extract, did not influence genotoxicity.

• Journal of Oral Medicine and Pain
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• v.32 no.4
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• pp.375-381
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• 2007

Occlusal stabilization appliance is one of the most common treatment option for management of temporomandibular disorders. It acts in oral cavity for several hours per day, and usually it will take at least 6 months to 2 years of total wearing periods to take a treatment goal. In the oral cavity, occlusal stabilization appliance, unintentional manner, is able to acts as a reservoir of bacteria and protect bacteria from saliva and oxygen. This condition is so favorable to many bacteria such as S. mutans and other anaerobes, usually have been reported as causative factors of dental caries, periodontal disease and oral malodor. In this study, we investigated anaerobic bacteria and S. mutans count before and after occlusal stabilization appliance use to evaluate the possible role of occlusal stabilization appliance as protector of these bacteria. Four men(average 27.5 years) wore maxillary occlusal stabilization appliance at each night(average 9 hours) for 5 days. we swabbed saliva-plaque mixed sample at 3 different site(maxillary left 2nd molar, maxillary left central incisor, mandibular left 2nd molar) before and after occlusal stabilization appliance use. Each samples were plated in (1) anaerobic blood agar medium, (2) selective S. mutans medium(MS-MUTV) and incubated in anaerobic chamber($CO^2$ 10%, $37^{\circ}C$) for 72 hours. Each bacterial colony forming unit(CFU) were counted with naked eyes. From obtained data, we can conclude as follows: 1. There was some changes about anaerobic bacteria and S. mutans count in oral cavity after occlusal stabilization appliance use. 2. The number of anaerobic bacteria was significantly increased at maxillary 2nd molar(P=0.003), maxillary central incisor(P=0.020) after occlusal stabilization appliance use compared with before. 3. Occlusal stabilization appliance use itself had indirect effect to increase the number of anaerobic bacteria at other uncovered opponent tooth site. 4. The number of S. mutans was significantly increased at maxillary 2nd molar(P=0.043), maxillary central incisor (P=0.049) after occlusal stabilization appliance use compared with before. 5. Occlusal stabilization appliance use itself had not any effect on the number of S. mutans at other uncovered opponent tooth site.

• Journal of the Korea Organic Resources Recycling Association
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• v.12 no.4
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• pp.139-147
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• 2004

We have isolated two bacterial strains, FM-02 and AL-02, which produced EPS from forest soil for the restoration of forest fire by promoting soil aggregation. FM-02 was found to be Gram negative rod and belong to Beta Proteobacterium sp. through 16s-rDNA sequence analysis, and AL-02 was Gram positive rod and showed 81% of similarity to Zoogloea sp. through the analysis of 16s-rDNA sequence. FM-02 and AL-02 produced about 1.8g and 8.3g of EPS, respectively, per 1L of culture as dry weight. Flocculation activity (FA) was also measured in two strains. FM-02 showed 2.31 FA against active carbon, and AL-02 showed 6.21 FA against kaolin clay. From these results, we expect that AL-02 strain will be applied as a good biological material for the reduction of forest soil erosion by wild and rain after fire through promoting coagulation of soil particles.

• Korean Journal of Soil Science and Fertilizer
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• v.33 no.4
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• pp.266-274
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• 2000

Understanding of microbial community structure in soil-root system is necessary to use beneficial soil and rhizosphere microbes for improvement of crop production and biocontrol. The knowledge of behavior and function of microbes in soil-root system plays a key role for the application of beneficial inocula. Because the majority of the intact bacteria in soil are unable to grow on nutrient media, both culturable and nonculturable bacteria have to be studied together. In our study, culture-independent survey of bacterial community in the soil-root system of red pepper fields was conducted by the sequence analysis of three universal clone libraries of genes which code for small-subunit rRNA (rDNA). Universal small subunit rRNA primers were used to amplify DNA extracted from each sample and PCR products were cloned into pGEM-T. Out of 27 clones sequenced, 25 clones were from domain bacteria. Two of the rDNA sequences were derived from eukaryotic organelles. Within the domain bacteria, several kingdoms were represented : the Proteobacteria (16 clones). Cytophyga-Flexibacter-Bacteroides group (2 clones). the high G+C content gram-positive group(1 clone) and 4 unknown clones.

• The Journal of the Korean bone and joint tumor society
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• v.14 no.2
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• pp.203-207
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• 2008

Rapid destructive hip osteoarthritis is a rare subset of osteoarthritis with rapid destruction of the hip joint within months of the onset of symptoms. The entity simulates rheumatoid arthritis, septic arthritis, neuropathy or malignant bone tumor. We report a case of rapidly destructive coxarthrosis of the right hip joint initially misdiagnosed as a malignant bone tumor at outside hospital in a 80-year-old woman.

• 우유
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• s.63 winter
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• pp.15-19
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• 1995

MBC의 무책임한 보도와 이에 편승한 파스퇴르의 이기적인 비방광고로 고름우유 파동이 사회문제화 되자 우유전문가이며 세균학자인 강국희 교수는 학자적 양심으로 그 진상을 정확히 규명해 진정시키고자 ‘고름우유란 없다’는 장문의 글을 발표하고 본지에도 기고했다. 그 후 11월 20일 보건복지부에서 시판 우유 중 5개 제품에서 인체에는 해가 없는 극미량지만 항생 · 항균물질이 검출됐다고 발표해 그 파장이 커지가 그 실상을 밝히기 위해 ‘우유항생물질을 해부 한다’는 글을 추가로 발표했다. 본지는 이를 발췌하여 게재했다.

• Proceedings of the Korean Aquaculture Society Conference
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• 2004.05a
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• pp.417-418
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• 2004

• The Microorganisms and Industry
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• v.19 no.1
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• pp.2-7
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• 1993

polyamine을 생합성하는 율속단계효소인 ornithine decarboxylase(ODC)는 미생물에서 많이 연구되어 왔으며 실제적으로 이 효소에 대한 연구는 세균에서 그 효시를 이루었다(1-5,19,35). 최근 들어서는 Escherichia coli(1-22), Saccharomyces cerevisiae (35-40), Neurospora crassa, Physarum polycephalum에서 보다 상세한 연구가 이루어졌는데, 본 고에서는 Escherichia coli, Saccharomyces cerveisiae에 관하여 좀 더 자세히 살펴보고자 한다. Polyamines의 연구나 ODC효소에 대한 연구는 미생물이 많이 이용되었는데, 이는 비교적 쉽게 세포배양이 되기도 하지만, ODC가 결손된 변이주를 만들기가 비교적 용이한 이유도 있었다.

• Proceedings of the Korean Society of Veterinary Pathology Conference
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• 2001.09a
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• pp.31-31
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• 2001

우리나라 해산어류양식의 중요양식품종인 조피볼락은 양식년수가 증가됨에 따라 양성과정 중에 여러 가지 폐사 유형을 동반하고 있다. 최근 남해안 가두리에서는 수면을 부유하는 등 이상유영을 동반한 복수증예가 연중 산발적으로 발생하고 있으며, 특히 수온이 15$^{\circ}C$ 이하로 떨어지는 10월에서 이듬해 2월에 걸친 저수온기에 다발하는 경향을 보이고 있다. 복수증은 부종 소견의 하나로, 체강 내에 체액이 고이는 증상으로서 세균 및 바이러스 감염병을 중심으로 각종 어류 질병에서 동반되고 있으나, 복수증에 대한 이해는 부족한 실정이다. (중략)