• Journal of Korean Neurosurgical Society
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• v.64 no.3
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• pp.367-373
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• 2021

Secondary neurulation (SN) is a critical process to form the neural tube in the posterior region of the body including the tail. SN is distinct from the anteriorly occurring primary neurulation (PN); whereas the PN proceeds by folding an epithelial neural plate, SN precursors arise from a specified epiblast by epithelial-to-mesenchymal transition (EMT), and undergo self-renewal in the tail bud. They finally differentiate into the neural tube through mesenchymal-to-epithelial transition (MET). We here overview recent progresses in the studies of SN with a particular focus on the regulation of cell lineage, self-renewal, and EMT/MET. Cellular mechanisms underlying SN help to understand the functional diversity of the tail in vertebrates.

• Journal of Korean Neurosurgical Society
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• v.64 no.3
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• pp.359-366
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• 2021

Neuromesodermal progenitors (NMPs) constitute a bipotent cell population that generates a wide variety of trunk cell and tissue types during embryonic development. Derivatives of NMPs include both mesodermal lineage cells such as muscles and vertebral bones, and neural lineage cells such as neural crests and central nervous system neurons. Such diverse lineage potential combined with a limited capacity for self-renewal, which persists during axial elongation, demonstrates that NMPs are a major source of trunk tissues. This review describes the identification and characterization of NMPs across multiple species. We also discuss key cellular and molecular steps for generating neural and mesodermal cells for building up the elongating trunk tissue.

• Proceedings of the Korea Information Processing Society Conference
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• 2020.11a
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• pp.663-664
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• 2020

차세대 염기서열 분석 기술은 성능과 비용 면에서 매우 향상되어 한 개체 내 여러 세포의 유전자 분석이 가능한 수준이다. 한 개체 내 여러 조직 세포의 유전자는 모두 동일하지 않기 때문에 여러 조직 세포의 Lineage 를 계층적으로 표현하고 이를 조직 세포 간 변이 정도를 파악하는 데 활용한다면 암 돌연변이 발생 등을 미리 예측할 수 있다. 본 논문은 한 개체 내 여러 조직 간 변이를 관찰하기 위해 변이 검출 데이터를 계층적 군집 방법을 이용해 분석하고 이를 시각화 하는 방법을 제안한다. 실제의 8 개 조직 세포의 유전자를 분석하고 변이를 검출하여 Dendrogram 그래프로 시각화 하였다.

• Research in Plant Disease
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• v.26 no.2
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• pp.79-87
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• 2020

Fusarium wilt caused by Fusarium oxysporum f. sp. fragariae (Fof) is the most important diseases of a strawberry field in Korea. We surveyed phylogenetic analysis, pathogenicity test, and fungicide response about Fof isolates isolated from Korea. Twenty-seven isolates of F. oxysporum isolated from strawberry plants were conducted in this study. Specific amplification by Fof specific primer was confirmed in all 26 isolates except Fo080701 isolate. The nuclear ribosomal intergenic spacer region and the translation elongation factor EF-lα gene sequences of isolates revealed three main lineages. Most of all isolates were contained DNA lineage group 1, but 2 and 3 group was shown only one and three isolates, respectively. All isolates were shown in pathogenicity with cv. Seolhyang. The EC₅₀ mean values of prochloraz ranged 0.02-0.1 ㎍/ml except for Fo080701 and effectively inhibited mycelial growth at low concentrations. The EC₅₀ value of metconazole was also 0.04-0.22 ㎍/ml, showing a similar inhibitory effect to that of prochloraz. The EC₅₀ value of pyraclostrobin was 0.23-168.01 ㎍/ml, which was different according to the strain. In the field trial, boscalid+fludioxonil, fluxapyroxad+pyraclostrobin, and prochloraz manganese were selected as the effective fungicides for controlling Fusarium wilt.

• Korean Journal of Microbiology
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• v.45 no.2
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• pp.112-118
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• 2009

Ammonia-oxidizing bacteria (AOB) are chemolithoautotrophs that play a key role in nitrogen removal from advanced wastewater treatment processes. Various AOB species inhabit and their community compositions vary over time in the wastewater treatment bioreactors. In this study, a hypothesis that operational and environmental conditions affect both the community compositions and the diversity of AOB in the bioreactors was proposed. To verify the hypothesis, the clone libraries based on ammonia monooxygenase subunit A were constructed using activated sludge samples from aerobic bioreactors at the Pohang, the Palo Alto, the Nine Springs, and the Marshall wastewater treatment plants (WWTPs). In those bioreactors, AOB within the Nitrosomonas europaea, N. oligotropha, N.-like, and Nitrosospira lineages were commonly found, while AOB within the N. communis, N. marina, and N. cryotolerans lineages were rarely detected in the samples. The AOB community structures were different in the bioreactors: AOB within the N. oligotropha lineage were the major microorganisms in the Pohang, the Palo Alto, and the Marshall WWTPs, while AOB within the N. europaea lineage were dominant in the Nine Springs WWTP. The correlations between the AOB community compositions of the wastewater treatment bioreactors and their operational (HRT, SRT, and MLSS) and environmental conditions (temperature, pH, COD, $NH_3$, and $NO_3{^-}$) were evaluated using a multivariate statistical analysis called the Redundancy Analysis (RDA). As a result, COD and $NO_3{^-}$ concentrations in the bioreactors were the statistically significant variables influencing the AOB community structures in the wastewater treatment bioreactors.

• Journal of the Korean Home Economics Association
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• v.38 no.4
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• pp.129-142
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• 2000

The written lineages of 14 confucian royal famines were analyzed on the basis of the distance of family relationship to reveal some characteristics of the continuation principles in Chosun dynasty. The result shows that they used the nile of adopting the son of Legitimate wife as the head of the family, who had the same sumame and also ability enough to lead their clan. This nile has been observed for five hundred years over some socio-political differences of respective periods.

• SUVANNABHUMI
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• v.11 no.2
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• pp.7-21
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• 2019

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.16
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• pp.7219-7229
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• 2015

Background: Chromosomal aberrations identified in acute lymphoblastic leukemia (ALL) have an important role in disease diagnosis, prognosis and management. Information on karyotype and associated clinical parameters are essential to physicians for planning cancer control interventions in different geographical regions. Materials and Methods: In this study, we present the overall frequency and distribution patterns of chromosomal aberrations in both children and adult de novo B lineage ALL Indian patients using conventional cytogenetics, interphase FISH and multiplex RT-PCR. Results: Among the 215 subjects, cytogenetic results were achieved in 172 (80%) patients; normal karyotype represented 37.2% and abnormal 62.8% with a distribution as follows: 15.3% hypodiploidy; 10.3% hyperdiploidy; 15.8% t(9;22); 9.8% t(1;19); 3.7% t(12;21); 2.8% t(4;11); 2.8% complex karyotypes. Apart from these, we observed several novel, rare and common chromosomal rearrangements. Also, FISH studies using LSI extra-signal dual-color probes revealed additional structural or numerical changes. Conclusions: These results demonstrate cytogenetic heterogeneity of ALL and confirm that the incidence of chromosomal abnormalities varies considerably. To the best of our knowledge, this is one of the largest reported series of cytogenetic investigations in Indian B-lineage ALL cases. In addition, ongoing cytogenetic studies are warranted in larger groups of B-lineage ALL cases to identify newly acquired chromosomal abnormalities that may contribute to disease diagnosis and management.

• Proceedings of the Korean Society of Developmental Biology Conference
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• 2003.10a
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• pp.60-60
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• 2003

Embryonic stem (ES) cells have property of self-renewal and can differentiate into the cells of all three primary germ layers. Recently, many growth factors, alteration of culture condition and gene modifications have been used to differentiate mouse and human ES cells into specific cell types. This study was performed to evaluate the differentiation protocol for human ES cells to the endodermal lineage cells. Human ES cells (Miz-hESl ) were cultured on STO feeder layer mitotically inactivated with mitemycin C, and embryoid bodies (EBs) were formed by suspension culture. Differentiation protocol of EBs consisted of three steps: stage I, culture of EBs for 6 days with ITSFn medium; stage II, culture of stage I cells for 8 days with N2 medium ; stage III, culture of stage II cells for 22 days with N2 medium. mRNA levels of the endodermal lineage differentiation genes were analyzed by semi- quantitative RT-PCR. The Oct-4 expression, a marker of the pluripotent state, was detected in undifferentiated human ES cells but progressively decreased after EBs formation. Differentiating human ES cells expressed marker genes of endodermal differentiation and pancreatic islet cells. GATA4, a-fetoprotein, Glut-2, and Ngn3 were expressed in all stages. However, albumin and insulin were expressed in only stage III cells. The human ES cells can be differentiated into endodermal lineage cells by multiple step culture system using various supplements. We are developing the more effective protocols for guided differentiation of human ES cells.

• Journal of fish pathology
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• v.23 no.1
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• pp.1-8
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• 2010

Infectious hematopoietic necrosis virus (IHNV) is the causative agent of IHN, one of the most serious viral diseases of salmonid fish. In this study, glycoprotein (G) gene nucleotide sequence of isolated IHNV RtWanju09 from Jeollabuk-do province was analyzed to evaluate their genetic relatedness to worldwide isolates. As the result, it was revealed that IHNV RtWanju09 isolate belongs to JRt Shizuoka lineage with IHNV RtPy91 and RtJe00. The genetic diversity of G gene between RtWanju09 isolate and RtPy91 isolate from Gangwon-do province was 1.77% and maximum nucleotide diversity among the JRt Shizuoka lineage in Korea was 3.03% during the past 20 years, supporting that the continuous evolution has been occurred among JRt Shizuoka isolates. It was believed that IHNV RtWanju09 isolate has been introduced by the movement of contaminated eggs with IHNV from Gangwon-do to Jeollabuk-do by the reason that the eyed eggs in Jeollabuk-do province used to be obtained from Gangwon-do province. In this study, the domestic transfer of IHNV was firstly investigated by the transfer history of eggs and the phylogenetic analysis using IHNV glycoprotein gene sequence.