• Food Industry And Nutrition
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• v.11 no.3
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• pp.6-11
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• 2006

바이러스성 식중독은 장염을 일으키는 원인 병원체 중 노로바이러스에 의해 흔히 발생하며 이외에도 아스트로바이러스나 로타바이러스에 의한 집단 설사 사례가 국내에서 보고된 바 있다. 노로바이러스는 식중독과 관련하여 특히 오염된 식수와 굴 등 어패류의 생식을 통한 감염 사례가 많이 보고되어 있으나 사람 간 전파도 흔히 일어나는 전염력이 매우 높은 바이러스이다. 국내에서는 1999년 이후 보고가 되고 있으며 최근 집단 급식과 관련된 대형 식중독 사례들이 보고되면서 학교급식이 사회적인 이슈로 대두되고 있다. 2000년 이후 질병관리본부는 바이러스성 설사의 국내 발생현황을 파악하기 위하여 전국의 17개 시도보건환경 연구원과 노로바이러스를 포함한 4종의 바이러스성 장염원인 병원체에 대한 전국적인 실험실 감시체계를 운영한 결과 바이러스성 병원체가 확인된 사례의 약 18%에서 노로바이러스가 검출되었고, 집단설사 사례에서는 대부분 노로바이러스가 원인병원체로 확인되었다. 또한 노로바이러스의 조기 검출을 위해 질병관리본부는 2004년 중 노로바이러스 유전자 검출 kit를 자체적으로 제작하여 이를 전국의 시도 보건환경연구원을 연계한 감시체계에서 적극 활용함으로써 노로바이러스 집단설사사례의 조기 검출이 가능하게 되었고 지역내 노로바이러스 검출율을 높이는데 기여하였다. 국립보건연구원은 2003년과 2006년에 발생한 대규모 노로바이러스 식중독 사례 이외에도 산발적으로 지속적으로 발생하는 사례들을 조기에 탐지하고 국내에서 검출되는 설사바이러스 유전형 분포양상과 새로운 유전자형이나 변이주를 조기에 검출하고자 전국적인 노로바이러스 실험실 감시망을 강화하여 운영하고 있으며, 집단설사 발생시 각 사례의 연관성을 신속하게 분석할 수 있는 실시간 분자역학적 유전자 분석체계를 단계적으로 도입하고 있다. 실험실 감시체계 운영과 함께 집단 식중독 유발 병원체의 효율적인 관리를 위해 질병관리본부는 노로바이러스를 포함한 설사 유발 병원체를 신고대상 병원체로 지정(2006.06.12)하여 병원체 검출시 보고하도록 하고 관련 지침을 마련하였다. 노로바이러스가 지정전염병 병원체로 추가로 지정됨에 따라 집단 사례 및 실험실 감시사업을 통해 검출되는 병원체에 대한 보고가 강화되고 전파 방지와 2차 감염 사례 감소에도 기여할 수 있을 것으로 사료되며 전국의 실험실 감시망을 연결하는 국가 차원의 노로바이러스 실시간 분자역학적 분석체계 도입을 통해 노로바이러스 2차 감염을 줄이고 대규모 집단발병 및 유행의 조기 차단 효과를 가져올 수 있을 것이다.

• Korean Journal of Microbiology
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• v.54 no.1
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• pp.24-30
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• 2018

Norovirus infection is a leading cause of nonbacterial gastroenteritis outbreaks. New variants of GII.4 have emerged approximately every 2~3 years and have caused norovirus gastroenteritis pandemics globally. In this study, analysis and molecular genetic characteristics of the norovirus gastroenteritis outbreaks 2,917 samples in Gyeonggi-Do from 2014 to 2015. As a result, 247 samples out of 2,917 samples are positive for norovirus. Norovirus molecular genetic characteristics of the GI 8 types (GI-1, 2, 3, 4, 5, 6, 12, 14), GII 10 types (GII - 2, 3, 4, 5, 6, 11, 12, 14, 16, 17). Genome sequences of isolated noroviruses were similar to those of new GII.17 Kawasaki 2014 variants with 96.6 identity, suggesting that these viruses were imported from overseas. 44% of virus incidence was originated from school meal service. Therefore, a continuous monitoring and school sanitation should be required for preventing a massive virus outbreak.

• Korean Journal of Microbiology
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• v.54 no.2
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• pp.149-151
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• 2018

Clostridium perfringens is a Gram-positive, rod-shaped, anaerobic, spore-forming pathogenic bacterium, which belongs to the Clostridiaceae family. C. perfringens causes diseases including food poisoning in vertebrates and intestinal tract of humans. Bacteriophages that can kill target bacteria specifically have been considered as one of control methods for bacterial pathogens. Here, we report a draft genome sequence of the bacteriophage CP3 effective to C. perfringens. The phage genome comprises 52,068 bp with a G + C content of 34.0%. The draft genome has 74 protein-coding genes, 29 of which have predicted functions from BLASTp analysis. Others are conserved proteins with unknown functions. No RNAs were found in the genome.

• Journal of Life Science
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• v.32 no.1
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• pp.36-43
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• 2022

Mucosal immunity is a well-designed defense system that builds precise and dynamic relationships against pathogens, and the gastrointestinal tract is the most important organ with this system, acting as a guardian at the forefront of its activity. Salmonella spp. cause food poisoning, entering the body orally and mainly invading the Peyer's patches of the small intestine. Although Salmonella strains share similar mechanisms for inducing innate immunity, different serotypes may have different effects on the intestinal mucosa due to host specificities and pathogenicity. In this study, we evaluated the effects of Salmonella enteritidis infections in mouse intestine and observed significantly reduced dose-dependent survival rates in a challenge test. Flow cytometry data showed no significant differences in intestinal immune cell populations, although histology indicated increased mucin production and decreased goblet cell counts in the Salmonella-treated groups. Furthermore, Claudin expression was significantly decreased in the samples with Salmonella. To investigate the relationship between S. enteritidis infection and inflammatory response, dextran sodium sulfate (DSS) was administered after infection and the results indicate lower survival rate after DSS treatment. In conclusion, we were able to identify the optimal concentration of S. enteritidis to modulate the intestinal mucosal immunity of mice and inflammatory response.

• Horticultural Science & Technology
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• v.32 no.3
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• pp.400-407
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• 2014

Urban farming supplies emotional stability and fresh vegetables to participating persons, however, no information regarding the biosafety of agricultural products from urban farming is available. Here, we collected 260 samples of Chinese cabbages and lettuce from 4 urban community gardens and 6 roof gardens in Seoul from September through October 2012, and monitored the microbiological and parasitological contamination quantitatively and/or qualitatively. The mean counts of total aerobic bacteria and coliforms were $6.1{\pm}0.8\;log\;CFU{\cdot}g^{-1}$ ( range, $5.4{\pm}0.6{\sim}7.1{\pm}0.8\;log\;CFU{\cdot}g^{-1}$) and $4.0{\pm}0.7\;log\;CFU{\cdot}g^{-1}$ (range, $2.3{\pm}0.6{\sim}6.1{\pm}0.9\;log\;CFU{\cdot}g^{-1}$), respectively. Coliforms were detected on 59.6% among 260 vegetable samples. There were no significant differences in the contamination levels of total aerobic bacteria and coliforms between the Chinese cabbages and lettuce, whereas both levels of vegetables from urban community gardens were higher than those of roof gardens (p > 0.05). Escherichia coli was isolated at 3.1% among whole vegetables, and contamination level was $1.5{\pm}0.2\;log\;CFU{\cdot}g^{-1}$. Among foodborne pathogens, Staphylococcus aureus was detected in 1.5%, however, Salmonella spp., Listeria monocytogenes and E. coli O157:H7 were not detected on any of the vegetable samples. We also found undefined parasite eggs from two samples of Chinese cabbages (0.8% of total vegetables we tested). From these study, we found the presence of microbial contamination of agricultural products from urban farming, thus we need further concern to improve the biosafety during production of agricultural products.