• 한국동물위생학회지
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• 제32권4호
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• pp.315-323
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• 2009

Foot-and-mouth disease (FMD) virus exists in seven serotypes and is known to be a highly contagious disease that is hard to eradicate from the world. The O, A, Asia1 and SAT2 serotypes commonly infected cattle, sheep and goats during 2007~2009 throughout the world. In particular, the outbreak of the Asia1 serotype in China appeared in all areas from 2005 and is still present. Surprisingly, in 2009, Taiwan reported the first outbreak of the type O serotype since 2001. Then type A appeared in China for the first time since the early 1960s. The virus shows a close relationship to the viruses from Southeast Asia suggesting one or more recent introductions into China in the OIE reports. Recently the subtype of A/Iran05 spread to nearby countries exhibiting genomic evolution. The use of molecular epidemiology is an important tool in understanding and consequently controlling the FMD virus. The phylogenetic analysis with VP1 gene was especially useful for molecular epidemiological studies and showed the same pattern which matches with serotype classification. This paper describes basic information about the disease, and the serotype-specific characteristics and evolution to perform molecular epidemiological analysis. Furthermore, we show the importance of the genetic evolution on the FMD serotypes in global surveillance and molecular epidemiology of FMD for outbreak investigation.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2018년도 추계학술대회
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• pp.43-43
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• 2018

Mutation breeding by radiation is useful for improving various crop species. Up to now, a total of 170 soybean mutant varieties have been released in the world, which is the second most registered varieties after rice. Despite the economic importance of soybean, there have been no TRAP marker system studies on genetic relationships between/among mutant lines. To develop a strategy of Mutant Diversity Pool (MDP) conservation, a study on the genetic diversity of 210 soybean mutant lines (8 cultivars and 202 mutants) was performed through a TRAP analysis. Sixteen primer combinations amplified a total of 551 fragments. The highest (84.00%) and lowest (32.35%) polymorphism levels were obtained with primers MIR157B + Ga5 and B14G14B + Ga3, respectively. The mean PIC values 0.15 varied among the primer combination ranging from 0.07 in B14G14B + Sal2 to 0.23 in MIR157B + Sa4. Phylogenetic, principal component analysis (PCA) and structure analysis indicated that the 210 lines belong to four groups based on the 16 combination TRAP markers. AMOVA showed 21.0% and 79.0% variations among and within the population, respectively. Overall, the genetic similarity of each cultivar and its mutants were higher than within other mutant populations. Our results suggest that the TRAP marker system may be useful for assessing the genetic diversity among soybean mutants and help to improve our knowledge of soybean mutation breeding.

• Parasites, Hosts and Diseases
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• 제44권3호
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• pp.187-196
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• 2006

The mammalian trematode Paragonimus westermani is a typical digenetic parasite, which can cause paragonimiasis in humans. Host tissues and blood cells are important sources of nutrients for development, growth and reproduction of P. westermani. In this study, a cDNA clone encoding a 47 kDa hemoglobinase of P. westermani was characterized by sequencing analysis, and its localization was investigated immunohistochemically. The phylogenetic tree prepared based on the hemoglobinase gene showed high homology with hemoglobinases of Fasciola hepatica and Schistosoma spp. Moreover, recombinant P. westermani hemoglobinase degradaded human hemoglobin at acidic pH (from 3.0 to 5.5) and its activity was almost completely inhibited by E-64, a cysteine proteinase inhibitor. Immunohistochemical studies showed that P. westermani hemoglobinase was localized in the epithelium of the adult worm intestine implying that the protein has a specific function. These observations suggest that hemoglobinase may act as a digestive enzyme for acquisition of nutrients from host hemoglobin. Further investigations may provide insights into hemoglobin catabolism in P. westermani.

• Parasites, Hosts and Diseases
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• 제54권4호
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• pp.455-460
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• 2016

Blastocystis is a common zoonotic enteric protozoan that has been classified into 17 distinct subtypes (STs). A cross-sectional study was conducted to determine the prevalence and subtype distributions of Blastocystis in villagers living along the Chao Phraya River, Ayutthaya Province, Thailand, and to assess the risk of zoonotic infection. In total, 220 stool samples were collected, and DNA was extracted. PCR and sequencing were performed with primers targeting the small-subunit ribosomal RNA (SSU rRNA) genes. Blastocystis was present in 5.9% (13/220) of samples, and ST3 (5.0%; 11/220) was the predominant subtype, followed by ST2 (0.45%; 1/220) and ST6 (0.45%; 1/220). Phylogenetic trees were constructed with the maximum-likelihood method based on the Hasegawa-Kishino-Yano + G + I model, neighbor-joining, and maximum parsimony methods. The percentage of bootstrapped trees in which the associated taxa clustered together was relatively high. All the sequences of the Blastocystis-positive samples (KU051524-KU051536) were closely related to those from animals (pig, cattle, and chicken), indicating a zoonotic risk. Therefore, the villagers require proper health education, especially regarding the prevention of parasitic infection, to improve their personal hygiene and community health. Further studies are required to investigate the Blastocystis STs in the animals living in these villages.

• Asian Pacific Journal of Cancer Prevention
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• 제17권9호
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• pp.4357-4361
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• 2016

Background: Whether there is any relationship between human papilloma virus (HPV) and breast carcinoma is not clear. Some previous studies have indicated a possible role in oncogenesis in the breast. In this study, we therefore analyzed the presence of HPV infection in breast tissues of Iranian women from Yazd city. Materials and Methods: In a cross-sectional study, formalin-fixed paraffin-embedded tissues from 87 patients with breast cancer and 84 cases with breast fibrocystic lesions (control group) were selected from a tissue archive. Grade of tumors and fibrocystic tissues were determined by two pathologists. The nested-PCR method was performed for detection of HPVs in samples. HPV genotypes were determined by sequencing and the phylogenetic tree depicted by MEGA software. Results: Of the 87 women with breast cancer, 22.9% (20 isolates) had positive results for HPV DNA. In the control group no HPV was detected. The HPV genotypes in positive samples were HPV-16 (35%) HPV-18 (15%), HPV-6 (45%) and HPV-11 (5%). The data did not approved a significant correlation between tissue pathology of breast cancer and the HPV genotype frequency. Conclusions: The data did not provide any evidence for a role of high risk HPV types in oncogenesis in the breast.

• 식물분류학회지
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• 제32권4호
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• pp.449-465
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• 2002

분자생물학적 자료에 의한 한국산 백합강 식물에 대한 분류학적 재검토를 시도하였다. 2가지의 다른 자료, 즉 엽록체 DNA인 rbcL 및 atpB sequence 자료분석에서 대체적으로 일치하는 계통수를 얻었다. 즉, 한국산 백합강은 Dahlgren 등의 분류체계에 의한 비짜루목, 백합목, 마목의 3목으로 구분되었다. 이중 비짜루목과 백합목의 유연관계를 추론하는 분자생물학적 연구에서 마목의 분류군이 군외분류군으로 사용되었다. 두 엽록체 DNA인 rbcL 및 atpB sequence 분석에서 붓꽃과는 백합과 보다는 비짜루과에 더 가까운 유연관계를 보여주었다. 그러나, 넓은 의미의 Narthecaceae (종전의 Melanthiaceae [국명부재]에 속한 분류군)는 비짜루목이나 백합목에 속하는 분류군들과 가까운 유연관계를 보이지 않았다. 이전의 은방울꽃과 [Ruscaceae] 내에 취급되었던 애기나리속, 나도옥잠화속, 죽대아재비속 등은 각각 Colchiaceae, 백합과, Caloghortaceae로 이전 되어야 한다는 결론이 내려졌다. 마지막으로 한국산 백합강에 속하는 과의 체계에 대해서 토의하였다.

• Parasites, Hosts and Diseases
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• 제53권1호
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• pp.13-19
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• 2015

Blastocystis sp. is a common zoonotic intestinal protozoa which has been classified into 17 subtypes (STs). A cross-sectional study was conducted to determine the prevalence and subtype distribution of Blastocystis in villagers living on the Thai-Myanmar border, where the risk of parasitic infection is high. A total of 207 stool samples were collected and DNA was extracted. PCR and sequencing using primers targeting small-subunit ribosomal RNA (SSU rRNA) gene were performed. The prevalence of Blastocystis infection was 37.2% (77/207). ST3 (19.8%; 41/207) was the predominant subtype, followed by ST1 (11.6%; 24/207), ST2 (5.3%; 11/207), and ST4 (0.5%; 1/207). A phylogenetic tree was reconstructed using the maximum likelihood (ML) method based on the Hasegawa-Kishino-Yano + G + I model. The percentage of bootstrapped trees in which the associated taxa clustered together was relatively high. Some sequences of Blastocystis positive samples (TK18, 39, 46, 71, and 90) were closely related to animals (pig and cattle) indicating zoonotic risks. Therefore, proper health education in parasitic prevention for the villagers should be promoted to improve their personal hygiene. Further longitudinal studies are required to monitor the prevalence of parasitic infections after providing health education and to investigate Blastocystis ST in animals living in these villages.

• Animal Systematics, Evolution and Diversity
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• 제27권1호
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• pp.1-17
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• 2011

Thais Roding, 1798, commonly known as rock-shell, is among the most frequently found gastropod genera worldwide on intertidal rocky shores including those of Japan, China, Taiwan and Korea. This group contains important species in many marine environmental studies but species-level taxonomy of the group is quite complicated due to the morphological variations in shell characters. This study examined the genetic variations and relationships among three Korean Thais species based on the partial nucleotide sequences of mitochondrial cox1 gene fragments. Phylogenetic trees from different analytic methods (maximum parsimony, neighbor-joining, and maximum likelihood) showed that T. bronni and T. luteostoma are closely related, indicating the most recent common ancestry. The low sequence divergence found between T. luteostoma and T. bronni, ranging from 1.53% to 3.19%, also corroborates this idea. Further molecular survey using different molecular marker is required to fully understand a detailed picture of the origin for their low level of interspecific sequence divergence. Sequence comparisons among conspecific individuals revealed extensive sequence variations within the three species with maximum values of 2.43% in T. clavigera and 1.37% in both T. bronni and T. luteostoma. In addition, there is an unexpectedly high level of mitochondrial genotypic diversity within each of the three Korean Thais species. The high genetic diversity revealed in Korean Thais species is likely to reflect genetic diversity introduced from potential source populations with diverse geographic origins, such as Taiwan, Hong Kong, and a variety of different coastal regions in South China and Japan. Additional sequence analysis with comprehensive taxon sampling from unstudied potential source populations will be also needed to address the origin and key factors for the high level of genetic diversity discovered within the three Korean Thais species studied.

• Ocean and Polar Research
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• 제25권4호
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• pp.607-615
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• 2003

Many organisms are known to survive in icy environments. These include both over wintering terrestrial insects and plants as well the marine fish inhabiting high latitudes. The adaptation of these organisms is both a fascinating and important topic in biology. Marine teleosts in particular, can encounter ice-laden seawater that is approximately $1^{\circ}C$ colder than the colligative freezing point of their body fluids. These animals produce a unique group of proteins, the antifreeze proteins (AFPs) or antifreeze glycoproteins (AFGPs) that absorb the ice nuclei and prevent ice crystal growth. Presently, there are at least four different AFP types and one AFGP type that are isolated from a wide variety of fish. Despite their functional similarity, there is no apparent common protein homology or ice-binding motifs among these proteins, except that the surface-surface complementarity between the protein and ice are important for binding. The remarkable diversity of these proteins and their odd phylogenetic distribution would suggest that these proteins might have evolved recently in response to sea level glaciations just 1-2 million years ago in the northern hemisphere and 10-30 million years ago around Antarctica. Winter flounder, Pleuronectes americanus, has been used as a popular model to study the regulation of AFP gene expression. It has a built-in annual cycle of AFP expression controlled negatively by the growth hormone. The signal transduction pathways, transcription factors and promoter elements involved in this process have been studied in our laboratory and these studies will be presented.

• Journal of Species Research
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• 제4권2호
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• pp.109-126
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• 2015

As a subset study to discover indigenous prokaryotic species in Korea, a total of 39 bacterial strains assigned to the classes Betaproteobacteria and Gammaproteobacteria were isolated from diverse environmental samples collected from soil, tidal flat, freshwater, seawater, seaweed, wetland, plant roots, guts of insects, and fermented foods. From the high 16S rRNA gene sequence similarity (>99.1%) and formation of a robust phylogenetic clade with the closest species, it was determined that each strain belonged to each independent and predefined bacterial species. There is no official report that these 39 species have been described in Korea; therefore 4 species of 4 genera in the order Burkholderiales and 1 species in the order Neisseriales within the class Betaproteobacteria, and 10 species of 6 genera in the order Alteromonadales, 11 species of 3 genera in the order Pseudomonadales, 4 species of 4 genera in the order Enterobacteriales, 2 species of 2 genera in the order Vibrionales, 1 species in the order Aeromonadales, 3 species of 3 genera in the order Oceanospirillales, 2 species of 2 genera in the order Xanthomonadales, and 1 species in the order Chromatiales within the Gammaproteobacteia are reported for proteobacterial species found in Korea. Gram reaction, colony and cell morphology, basic biochemical characteristics, isolation source, and strain IDs are also described in the species description section.