• Parasites, Hosts and Diseases
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• v.36 no.3
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• pp.191-198
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• 1998

The responses to antifolales of ToxopLasmc Bondii were investigated by measuring the dihydrorolate redLlctase (DHFR) activity. quantity of DHFR mRNA, and single-strand conformational polymorphism (SSCP) pattern. Pyrimethamine (PYM) and methotrexate (MTX) were tested ds anlifolates. When T. gondii was treated wish PYM, the viability was decreased by the increasing concentration of PYM. DHFR activity tended to increase as the passage proceeded. and the quantity of mRNA expressed was also increased according to passages. The viability of 7. gonnii was decreased by the increasing concentration of MTX, but it was maintained over 40% up to $100{\;}{\mu\textrm{m}}$ MTX. DHFR activity was 77.4% in the 1st passage ($1{\;}{\mu\textrm{m}}$). 82.2% in the 4th passage ($10{\;}{\mu\textrm{m}}$), and 141.3% in the 7th passage ($100{\;}{\mu\textrm{m}}$) But no changes were detected in SSCP pattern of T gondii rxposvd to FYM and MTX. both. These results suggested that the response of T gondii to FYN was rofulalcd by transrriptional level and that, in MTX. the viability of T. gonnii was derived from increasing DHFK activity.

• Journal of Life Science
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• v.17 no.12
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• pp.1610-1615
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• 2007

Genus Sorbus is a long lived woody species that is primarily distributed throughout Asia and Europe. This species is regarded as very important herbal medicines in Korea and China. Sorbus commixta is primarily distributed throughout Europe. We evaluated a representative sample of the four taxa with nuclear ribosomal DNA internal transcribed spacer sequences (ITS) to estimate genetic relationships within genus. Aligned nucleotide sequences of the length of ITS1 were nearly constant within genus Sorbus varying from 219 in S. aucuparia to 218 in the rest species. Especially, the 5.8S subunit of all taxa of Sorbus was found to constant of 165 bp nucleotides. However, aligned nucleotide sequences of the length of ITS2 vary from 240 in S. sambucifolia var. pseudogrcilisto 245 in S. aucuparia. Total alignment length is 629 positions, of which 35 are parsimony-informative, 32 variable but parsimony-uninformative, and 552 constant characters. The base furtherance showed the difference to the by a total taxon: an average A and T are 17.7% and G and C are 30.4%, 34.2%, respectively. All the four taxa beginning with conserved base paired triplets emerging from single strand regions (domain I). Noteworthy, in the RNA secondary structure proposed for the three Korean Sorbus taxa RNA transcript ITS2, which shows a remarkedly well-conserved folding (domain II). When compared to the European Sorbus (S. aucuparia) of ITS2. ITS analysis may be useful in germ-plasm classification several taxa of genus Sorbus.

• Education of Primary School Mathematics
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• v.19 no.1
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• pp.1-18
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• 2016

Patterns are of great significance to develop algebraic thinking of elementary students. This study analyzed teaching methods of patterns in current elementary mathematics textbook series in terms of three main activities related to pattern generalization (i.e., analyzing the structure of patterns, investigating the relationship between two variables, and reasoning and representing the generalized rules). The results of this study showed that such activities to analyze the structure of patterns are not explicitly considered in the textbooks, whereas those to explore the relationship between two variables in a pattern are emphasized throughout all grade levels using function table. The activities to reason and represent the generalized rules of patterns are dealt in a way both for lower grade students to use informal representations and for upper grade students to employ formal representations with expressions or symbols. The results of this study also illustrated that patterns in the textbooks are treated rather as a separate strand than as something connected to other content strands. This paper closes with several implications to teach patterns in a way to foster early algebraic thinking of elementary school students.

• Journal of Korean Tunnelling and Underground Space Association
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• v.24 no.6
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• pp.495-512
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• 2022

Due to the concentration of population in the city center, the aboveground structures are saturated, and the development of underground structures becomes important. In addition, it is necessary to apply the reinforcement construction method for the pillar part of the adjacent tunnel that can secure stability, economy, and workability to the site. In this study, the tunnel pillar reinforcement method using prestress and grouting was reviewed. There are various reinforcement methods that can compensate for the problems of the side tunnel, but as the tunnel pillar construction method using prestress and grouting is judged to be excellent in field applicability, stability, and economic feasibility, it is necessary to review the theoretical and numerical analysis of the actual behavior mechanism. Therefore, a scaled-down model experiment was conducted. The reduced model experiment was divided into PC stranded wire + steel pipe reinforcement grouting + prestress (Case 1), PC strand + steel pipe reinforcement grouting (Case 2), and no reinforcement (Case 3), and the displacement of the pillar and the earth pressure applied to the wall were measured. Through experiments, it was confirmed that the PC stranded wire + steel pipe reinforcement grouting + prestress method is the most excellent reinforcement method among various construction methods. It was judged that it could be derived.

• Journal of the Korea institute for structural maintenance and inspection
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• v.23 no.1
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• pp.147-153
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• 2019

The prestressing steel wire, which is applied a tension to reinforce the structure, is applied flexure simultaneously by the duct and the deviator. In order to evaluate the deflected tensile performance of the prestressing steel wire subjected to both tensile and flexural stresses, the numerical analysis for 600 cases with variables of wire diameters, mandrel diameters, and friction coefficient between mandrel and steel wire was performed. As the result of analysis, the larger the diameter of the steel wire was, the lower the deflected tensile performance was, and the effect decreased with the increase of the wire elongation. The effect of mandrel diameter and friction coefficient between mandrel and wire on the deflected tensile performance of the wire was very small. But the deflected tensile performance and the friction coefficient between mandrel and strand showed a relatively high correlation. Therefore, it is necessary to make enough large elongation to secure the deflected tensile performance. If there is a restriction on the elongation, it is necessary to reduce the diameter of the steel wire to an appropriate value, and to increase the friction between steel wires by adjusting the surface condition of the steel wire.

• Journal of Veterinary Science
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• v.21 no.2
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• pp.26.1-26.14
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• 2020

Pancreatic ductal adenocarcinoma is a lethal cancer type that is associated with multiple gene mutations in somatic cells. Genetically engineered mouse is hardly applicable for developing a pancreatic cancer model, and the xenograft model poses a limitation in the reflection of early stage pancreatic cancer. Thus, in vivo somatic cell gene engineering with clustered regularly interspaced short palindromic repeats is drawing increasing attention for generating an animal model of pancreatic cancer. In this study, we selected Kras, Trp53, Ink4a, Smad4, and Brca2 as target genes, and applied Campylobacter jejuni Cas9 (CjCas9) and Streptococcus pyogens Cas9 (SpCas9) for developing pancreatic cancer using adeno associated virus (AAV) transduction. After confirming multifocal and diffuse transduction of AAV2, we generated SpCas9 overexpression mice, which exhibited high double-strand DNA breakage (DSB) in target genes and pancreatic intraepithelial neoplasia (PanIN) lesions with two AAV transductions; however, wild-type (WT) mice with three AAV transductions did not develop PanIN. Furthermore, small-sized Cjcas9 was applied to WT mice with two AAV system, which, in addition, developed high extensive DSB and PanIN lesions. Histological changes and expression of cancer markers such as Ki67, cytokeratin, Mucin5a, alpha smooth muscle actin in duct and islet cells were observed. In addition, the study revealed several findings such as 1) multiple DSB potential of AAV-CjCas9, 2) peri-ductal lymphocyte infiltration, 3) multi-focal cancer marker expression, and 4) requirement of > 12 months for initiation of PanIN in AAV mediated targeting. In this study, we present a useful tool for in vivo cancer modeling that would be applicable for other disease models as well.

• Journal of Animal Science and Technology
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• v.65 no.6
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• pp.1308-1322
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• 2023

Minerals is required small amounts among various nutrients, but it has a significant impact on sow longevity and reproduction performance. This study was carried out to see the beneficial effects of marine-derived Ca-Mg complex on the reproductive performance of sows during four-parity periods. Seventy-two gilts ([Yorkshire × Landrace] × Duroc), with an average body weight of 181 kg, were randomly allocated to three groups; CON (basal diet), 0.3LC (CON - MgO - 0.3% limestone + 0.4% Ca-Mg complex), and 0.7LC (CON - MgO - 0.7% limestone + 0.4% Ca-Mg complex). During parity 3 and 4, the expression level of SCD gene was lower in the umbilical cord of piglets born to 0.3LC and 0.7LC sows compared with the CON sows. During parity 2, 3 and 4, SLC2A2 and FABP4 gene expressions were higher in the umbilical cord of piglets born to 0.7LC sows and the placenta of sows from 0.3LC groups, respectively. Ca-Mg complex increased (p < 0.05) Ca and Mg concentrations in sows and their piglets' serum as well as in colostrum regardless of parities. The serum vitamin D concentration was higher (p < 0.05) in their first parity, whereas serum prolactin and estrogen concentrations were higher (p < 0.05) during the fourth and third parity, respectively. The growth hormone concentrations were higher (p < 0.05) in the piglets born to sows during the first and second parity. The fat and immunoglobulin A (IgA) concentrations in colostrum were higher (p < 0.05) during the third and fourth parity, respectively. A reduction (p < 0.05) in salivary cortisol, epinephrine, and norepinephrine concentrations was observed in 0.3LC and 0.7LC sow groups compared with CON after farrowing regardless of parity, however before farrowing, a reduction in norepinephrine was observed. Before farrowing, the epinephrine and norepinephrine concentrations were higher (p < 0.05) during the first and second parity. After farrowing, the concentration of these hormones was higher during the second parity. Taken together, sows' parity and dietary Ca-Mg complex supplementation influenced serum metabolites, colostrum nutrients, stress hormones as well as the gene expressions related to lipid and glucose metabolism.

• Korean Journal of Poultry Science
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• v.50 no.4
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• pp.193-202
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• 2023

Influenza IAVs are encapsulated negative-strand RNA viruses that infect many bird species' respiratory systems and can spread to other animals, including humans. This work reanalyzed previous microarray datasets to identify common and specific differentially expressed genes (DEGs) in chickens, as well as their biological activities. There were 760 and 405 DEGs detected in HPAIV and LPAIV-infected chicken cells, respectively. HPAIV and LPAIV have 670 and 315 DEGs, respectively, with both viruses sharing 90 DEGs. Because of HPAIV infection, numerous genes were implicated in a fundamental biological function of the cell cycle, according to the functional annotation of DEGs. Of the targeted genes, expressions of CDC Like Kinase 3 (CLK3), Nucleic Acid Binding Protein 1 (NABP1), Interferon-Inducible Protein 6 (IFI6), PIN2 (TERF1) Interacting Telomerase Inhibitor 1 (PINX1), and Cellular Communication Network Factor 4 (WISP1) were altered in DF-1 cells treated with polyinosinic:polycytidylic acid (PIC), a toll-like receptor 3 (TLR3) ligand, suggesting that transcription of these genes be controlled by TLR3 signaling. To gain a better understanding of the pathophysiology of AIVs in chickens, it is crucial to focus more research on unraveling the mechanisms through which AIV infections may manipulate host responses during the infection process. Insights into these mechanisms could facilitate the development of novel therapeutic strategies.

• Annals of Hepato-Biliary-Pancreatic Surgery
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• v.28 no.2
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• pp.144-154
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• 2024

Backgrounds/Aims: Socioeconomic determinants of health are incompletely characterized in cholangiocarcinoma (CCA). We assessed how socioeconomic status influences initial treatment decisions and survival outcomes in patients with CCA, additionally performing multiple sub-analyses based on anatomic location of the primary tumor. Methods: Observational study using the 2018 submission of the Surveillance, Epidemiology, and End Results (SEER)-18 Database. In total, 5,476 patients from 2004-2015 with a CCA were separated based on median household income (MHI) into low income (< 25th percentile of MHI) and high income (> 25th percentile of MHI) groups. Seventy-three percent of patients had complete follow up data, and were included in survival analyses. Survival and treatment outcomes were calculated using R-studio. Results: When all cases of CCA were included, the high-income group was more likely than the low-income to receive surgery, chemotherapy, and local tumor destruction modalities. Initial treatment modality based on income differed significantly between tumor locations. Patients of lower income had higher overall and cancer-specific mortality at 2 and 5 years. Non-cancer mortality was similar between the groups. Survival differences identified in the overall cohort were maintained in the intrahepatic CCA subgroup. No differences between income groups were noted in cancer-specific or overall mortality for perihilar tumors, with variable differences in the distal cohort. Conclusions: Lower income was associated with higher rates of cancer-specific mortality and lower rates of surgical resection in CCA. There were significant differences in treatment selection and outcomes between intrahepatic, perihilar, and distal tumors. Population-based strategies aimed at identifying possible etiologies for these disparities are paramount to improving patient outcomes.

• Journal of the Korea institute for structural maintenance and inspection
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• v.28 no.4
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• pp.21-27
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• 2024

In this study, the corrosion density of tendon was evaluated with changing chloride and hydroxide ions. To simulate an accelerated corrosive environment, wet sand was used instead of concrete, and the tests were conducted considering three levels of chloride concentration (0.0, 0.125, and 0.250mol/l ) and three [Cl^-]/[OH^-] ratios (0.3, 0.6, and 0.9). The corrosion density was measured to 5.13 µA/cm² at 0.0mol/l and increased with the chloride concentration. Additionally, no significant differences were observed over 0.125mol/l of chloride concentration. When [OH^-] increased with a given chloride concentration (0.125mol/l), the corrosion density decreased linearly, showing effective control of corrosion density even at high chloride concentrations. Notably, the measured corrosion amounts were lower than those under of 0.0mol/l condition. Furthermore corrosion density and influencing parameters were normalized with the maximum and minimum results, and the relation between them was analyzed.