• Korean Journal of Microbiology
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• v.44 no.2
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• pp.135-139
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• 2008

Fecal specimens from acute gastroenteritis in Seoul from 2004 to 2007 were collected and then tested for the presence of norovirus by RT-PCR. 258 noroviruses were subjected to be futher characterized to sequencing analysis. The sequencing analysis showed that thirteen genotypes were detected (GII.1, GII.2, GII.3, GII.4, GII.5, GII.6, GII.8, GII.10, GII.l2, GII.13, GII.l5, GII.l6, GII.l7) and predominant genotype was GII.4 (76.7%) in the cases of norovirus detected sporadic acute gastroenteritis in Seoul. By this molecular investigation, genotypic distribution associated with norovirus infections will be used for control and prevention of norovirus related diseases.

• Microbiology and Biotechnology Letters
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• v.50 no.1
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• pp.126-134
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• 2022

Norovirus (NoV) is an important pathogen causing acute gastroenteritis worldwide. The purpose of the present study was the molecular characterization of NoV. A total of 408 stool specimens collected from hospitalized children associated with acute gastroenteritis in Chiang Rai, Thailand, 2015-2017 were investigated for the presence of NoVs by RT-PCR. NoV GII was detected in 32 samples (7.8%). Five distinct genotypes were identified, including GII.4 (13/32, 40.6%), GII.3 (11/32, 34.3%), GII.17 (4/32, 12.5%), GII.2 (2/32, 6.3%), and GII.14 (2/32, 6.3%). NoV infection occurred mostly in young children under 3 years of age (31/32, 96.9%) and showed the main peak in summer months from March to April (18/32, 56.3%). Phylogenetic analysis revealed that all 13 GII.4 strains clustered with GII.4 Sydney 2012 variant. Representative GII.3 strains were analyzed as a recombinant GII.3P[12] strain. Several amino acid differences were found in the antigenic epitopes and antibody binding sites of the VP1 capsid of the GII.3P[12]. Homology modeling of the P domain of the GII.3P[12] strain demonstrated that 10/13 amino acid differences were predicted to be located on the surface-exposed area of the capsid structure. These amino acid changes might affect the infectivity and the antigenicity of the recombinant GII.3P[12]. The prevalence of GII.4 Sydney 2012 and recombinant GII.3P[12] strains indicates the genetic diversity of circulating NoVs in Thailand, emphazing the importance of continuous surveillance to mornitor newly emerging NoV strains in the future.

• Journal of Life Science
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• v.26 no.8
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• pp.911-920
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• 2016

Norovirus is the most common causative agent of acute gastroenteritis. This study was carried out to investigate molecular epidemiology of norovirus infections from outbreaks in Busan from 2012 to 2015. Total of 581 stool specimens were collected from diarrhea patients in outbreaks in Busan, 71 samples were resulted in positive to norovirus. The data were analyzed according to seasonality, patient, age and gender. Noroviruses were detected most frequently during the winter season from November (25.4%) to February (28.2%). The age group from teens was the most susceptible to norovirus infections. To obtain the molecular genetic information of norovirus, we performed sequencing analyses of the strains detected. Norovirus genotypes have been reported to show high genetic diversity. Four kinds of GI genotypes (GI-1, GI-2, GI-3, GI-5) and five kinds of GII genotypes (GII-1, GII-4, GII-5, GII-6, GII-17) were indentified in outbreaks in Busan. Other previous studies have shown that GII-4 is the most predominant circulating in Korea and worldwide. The most prevalent norovirus genotypes of each year were GII-6 in 2012, GII-6 in 2013, GII-4 in 2014 and GII-6 in 2015. Except for 2014, GII-6 genotype was the most prevalent and predominant in Busan. We described the epidemiological analysis of the noroviruses in outbreaks in Busan. The result of this study will contribute to update the epidemiological data and improve hygiene and public health via sustainable surveillance.

• TTA Journal
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• s.43
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• pp.129-149
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• 1996

본 고에서는 Global Information Infrastructure (GII) 구축을 위하여 국제 표준화기구인 ITU, ISO, IEC 간에 최근 활동현황에 대하여 소개한다. 이를 위해 지난 1996년 1월 17-19일간에 열린 Global Information Infrastructure (GII)를 위하여 ITU-T 내에 Joint Rapporteur Group(JRG)회의 결과와 1월 24-26일간에 열린 ISO/IEC/ITU International GII 세미나에서 논의된 주요 결과를 정리한다. 먼저 ITU-T JRG 회의는 차기 연구회기(1997년-2000년)동안에 GII 표준화 절차와 기술적인 이슈를 ITU-T SG13을 중심으로 모든 ITU-T 스터디 그룹이 나누어서 진행해야될 업무를 정리하는 것이며 이는 1996년 10월에 개최될 WTSC에 제출할 예정이다. 다음으로 ISO/IEC/ITU International GII 세미나는 GII와 관련된 ITU, ISO, IEC 소속의 약 100여개의 표준화 그룹이 모여서 국제적으로 효과적인 작업을 하기 위한 방안을 모색하기 위하여 개최된 세미나이다. 여기는 통신망 관련하여 ITU, 상위 데이터 서비스와 관련된 ISO, 그리고 가전기기 및 단말장치와 관련된 IEC가 공통의 정보 하부구조의 건설을 위하여 더 이상 각기 표준화를 진행해서는 안 된다는 인식을 바탕으로 한 것이다.

• Fisheries and Aquatic Sciences
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• v.24 no.1
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• pp.10-18
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• 2021

Norovirus (NoV) prevalence was investigated in 100 sewage samples collected from 35 individual septic tanks around the drainage basin of Jaran Bay, Korea in January, May, and July of 2017. Genotypes and diversity of NoV strains detected in sewage samples were also assessed using the conventional RT-PCR and phylogenetic analysis. NoV GI or GII were detected in 22 (22.0%) and 24 (24.0%) samples, respectively. Thirteen genotypes were identified with three dominant genotypes (GI.9, GII.5 and GII.17) and GII.17 showed relatively higher prevalence during the survey period. GII.17 strains were clustered into recombinant type variant or NoV GII.17 Kawasaki variant. NoV GII.17 strains were considered emergent epidemic variants with widespread circulation. NoV surveillance strategy should include both environmental (sewage) and clinical data to reveal minor NoV genotypes likely cause of asymptomatic or underreported infections in the local population.

• Journal of Life Science
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• v.26 no.9
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• pp.999-1006
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• 2016

This paper studies an infection of norovirus and astrovirus in outbreaks in Korea. In March 2016, gastroenteritis outbreaks occurred in Busan. 522 students of three departments at university D had meeting at a restaurant near the university. Some of them had symptom such as diarrhea, vomiting. Epidemiological, laboratory and environmental investigations were performed to identify the agents of the outbreaks. Fecal specimens were collected from 35 students and 7 food handlers to identify causative viral agents. Norovirus genogroup GI and GII were detected from diarrhea patients. Astrovirus was also detected from some of them. In particular, these outbreaks were the first occurrence associated with astrovirus in Busan. Total of 42 samples were collected, and 24 samples resulted in positive to norovirus (16 cases) and astrovirus (8 cases). To identify the molecular genetic information of norovirus, we carried out sequences analysis of the detected strains. Norovirus genotypes were classified into GI.3, GI.4, GII.4, GII.13, GII.17 and GII.21. Astrovirus genotypes were seven astrovirus type 5 and one astrovirus type 2. We performed environmental investigation about water at the kitchen, but norovirus and astrovirus were not detected. The statistical analysis was conducted to evaluate the association between illness and risk factors. The results of this study may contribute to accumulate more the epidemiological data and develop the public health and hygiene.

• Electronics and Telecommunications Trends
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• v.11 no.2 s.40
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• pp.99-118
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• 1996

전세계는 소위 21세기 정보사회 진입을 향한 각종의 정보 기반구조 건설을 추진중에 있으며 국제표준화 기구를 비롯한 지역별, 국가별 표준화 기관들은 상호 연동환경 보장 및 적기 표준 공급을 위한 GII(Global Information Infrastructure) 표준화 추진계획을 발표하고 있다. 본 고에서는 ITU-T를 비롯한 ETSI(European Telecommunication Standards Institute), T1 Committee, TTC(Telecommunication Technology Council), GSC(Global Standards Collaboration) 등의 GII 표준화 활동현황을 기술하고, 초고속 정보통신 기반구축을 위한 표준화의 중요성 및 우리의 대응방안을 살펴보고자 한다.

• Journal of Life Science
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• v.21 no.6
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• pp.819-828
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• 2011

To inspect norovirus contamination of groundwater in south eastern areas of Korea, a systematic survey of groundwater in Busan, Ulsan, and Gyeongsangnam-do was performed for two years from 2009 to 2010. For this purpose, we first optimized the nested reverse transcription-PCR condition by designing two sets of primers for the detection of norovirus genogroups, GI and GII. Of 145 samples, 21 (25.9%) and 15 (23.4%) were norovirus positive in the dry season (April to June) and wet season (July to August), respectively. The detection frequencies of norovirus in Busan, Ulsan, and Gyeongsangnam-do were 15%, 7%, and 32%, respectively, reflecting a geographical difference in their distribution. The GI and GII isolates were 5 and 31, respectively, indicating the prevalence of GII in the tested areas. According to phylogenetic analysis of their nucleotide sequences, all of the GI isolates were identified to genotype GI.5 whilst the GII isolates were divided into two genotypes, GII.3 and GII.4. Neither physical-chemical parameters such as pH, temperature, oxidation-reduction potential, and dissolved oxygen, nor microbial indicators of water quality such as total bacteria, total coliforms, and Escherichia coli were statistically correlated with contamination of norovirus in the groundwater. Interestingly, however, the presence of norovirus was closely correlated with low turbidity (<0.50 NTU). The present study suggests that periodical monitoring of norovirus in groundwater is necessary to prevent epidemic waterborne diseases and to secure better sanitary conditions for public health.

• Microbiology and Biotechnology Letters
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• v.16 no.4
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• pp.320-326
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• 1988

Glucoamylase (EC 3.2.1.3) of Aspergillus sp. isolated from soil was partially purified by Sephacryl S-200 gel filtration and DEAE-Sephacel ion exchange chromatography, The glucoamylase activity was separated into two isozymes after DEAE-Sephacel ion exchange chromatrography. The optimum pH and temperature for both glucoamylase isozymes (GI, GII) were identical; pH 4.5 and temperature, $65^{\circ}C$. The molecular weights of GI and GII Isozymes were estimated to be 105,000, which were measured by gel filtration on Sephacryl S-200. Both isozymes were stable at pH ranges of 2 to 7, and up to 6$0^{\circ}C$. Glycerol was effective to stabilize the both isozymes. The activation energies of GI and GII isozymes were 10.63 and 10.33 kcal/mole, respectively. The enzyme activities of both isozymes were completely inactivated by addition of 0.1% Hg$^{++}$. In kinetic studies, the Km values of GI isozyme for soluble starch, dextrin, and glycogen were 0.62%, 0.32%, and 1.02%, respectively. For GII isozyme, they became 0.66%, 0.23%. and 0.14% for the substrates.

• Journal of Microbiology and Biotechnology
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• v.23 no.11
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• pp.1641-1643
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• 2013

Norovirus is the major cause of acute gastroenteritis worldwide. Between November 2012 and June 2013, 1718 stool samples were requested for norovirus antigen testing in the metropolitan areas of South Korea, and 91 samples were genotyped. The norovirus antigen-positive rate peaked at 52.8% in December 2013. A novel norovirus GII.4 variant, GII.4 Sydney 2012, was the most frequently found genotype (60.4%) during this period. This study demonstrates that norovirus activity increased during the winter of 2012-2013 in South Korea and that norovirus GII.4 Sydney 2012 was the cause of the norovirus epidemic during this period.