• Journal of The Korean Society of Grassland and Forage Science
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• v.19 no.3
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• pp.197-202
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• 1999

This study was conducted to evaluate the dry matter yield, quality and utilization of nutrients of crabgrass (Digitaria sanguinalis L.) dominant swards as a roughage sources. Dry matter yield of stages, chemical composition, DM digestibility was obserbed, and DM intake, digestibility and utilization of nitrogen and energy by Korean native goats was determined. Average DM yield of crabgrass dominant swards was obtained 8,473kg/ha, and average contents of CP, NDF, ADF and lignin was 13.0%, 74.1%, 38.6% and 10.4%, respectively. DM intake by Korean native goats was lower for crabgrass dominant swards than for sown grass swards(P>0.05). Digestibility of DM, celluar constituents, NDF and ADF by Korean native goats was significantly lower for crabgrass dominant swards than for sown grass swards(P<0.05). Utilization of nitrogen and energy by Korean native goats was significantly lower for crabgrass dominant swards than for sown grass sward(P<0.05). Above the results, although crabgrass dominant swards was lower than in DM yield, digestibility, and utilization of N and energy, but the DM yield of crabgrass dominant swards was obtained 8,471kg/ha without fertilizer. Therefore it appears that crabgrass dominant swards have a potential to provide roughage sources.

• Korean Journal of Microbiology
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• v.44 no.4
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• pp.277-281
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• 2008

HIV affects many organ systems. Patients with HIV infection have substantially increased risk of developing various cancers, primarily by opportunistic infection with oncogenic viruses due to their immunocompromised status. However, extensive evidence also indicates that the viral protein, Tat itself, may playas a major factor in the development of AIDS-related neoplasms. The molecular mechanism underlying Tat's oncogenic activity may include deregulation of cellular genes. Therefore, in this study, we examined the effect of HIV-l Tat on CD99 as one of the target cellular genes, which is a well-known tumor marker in several cancers. By using established HeLa clones that are stably expressing Tat, we found that CD99 is upregulated by endogenous Tat, whereas STAT3 is down regulated. Upon the screening of genes differentially expressed between Tat-stable cells and the control cells by using the gene fishing technique, DEG, we detected 3 genes which expression is affected by the presence of Tat. Furthermore, the methylation specific PCR analysis of the stably Tat expressing cell lines revealed that the CD99 promoter is de methylated in the presence of Tat. Taken together, these results open a potential role of CD99 in AIDS-related oncogenesis via epigenetic regulation by HIV-1 Tat.

• Journal of Mushroom
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• v.19 no.3
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• pp.140-149
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• 2021

Mushroom-derived polysaccharides, which are the primary bioactive constituents, are beneficial for human health. Polysaccharides have immuno-modulation, antitumor, and antioxidant properties. Additionally, they have antiviral properties and protect against chronic radiation stress. In this study, high yield water-soluble polysaccharides were obtained from Pleurotus djamor var. roseus basidiocarps. The crude polysaccharide (CP) was extracted sequentially by hot water and ethanol precipitation. The yield of the brown CPs was 5.6% dw. Diethylaminoethyl cellulose and Sepharose-6B column chromatography of CPs generated several fractions. Total glucan content was determined in all the fractions. The F1 fraction displayed the highest sugar content and was considered as a purified polysaccharide (PP). The total glucan and β-glucan content in the four fractions ranged between 76.85-2.95% and 75.08-1.46%, respectively. The yield of the PPs was 300 mg, and it was obtained as a white powder. The PPs were characterized by Fourier-transform infrared spectroscopy (FTIR) and thin-layer chromatography. The FTIR spectral details confirmed the presence of a xylopentose polysaccharide. The antioxidant activity of the PPs was evaluated using in vitro 1,1-diphenyl-2-picryl-hydrazyl (DPPH) free radical scavenging assay and superoxide radical scavenging assay. The PPs showed strong DPPH free radical and superoxide anion radical scavenging activities in a dose-dependent manner. Purified PPs free of phenolics, protein, and carbohydrates were mainly responsible for the radical scavenging activity. The data suggest the potential of PPs as natural antioxidants.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.4
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• pp.574-584
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• 2019

Objective: Research was conducted to test the effect of including fiber-rich feedstuffs in practical pig diets on nutrient digestibility, nitrogen balance and ammonia emissions from slurry. Methods: Three Vietnamese fiber sources were screened, namely cassava leaf meal (CL), cassava root residue (CR), and tofu by-product (TF). Accordingly, a control diet (Con) with 10% of dietary non-starch polysaccharides (NSP) and three test diets including one of the three fiber-rich feedstuffs to reach 15% of NSP were formulated. All formulated diets had the same level of crude protein (CP), in vitro ileal protein digestible and metabolisable energy, whereas the in vitro hindgut volatile fatty acid (VFA) production of the test diets was 12% to 20% higher than the control diet. Forty growing barrows with initial body weight at $28.6{\pm}1.93kg$ ($mean{\pm}standard$ deviation) were allocated to the four treatments. When pigs reached about 50 kg of body weight, four pigs from each treatment were used for a nitrogen balance trial and ammonia emission assessment, the remaining six pigs continued the second period of the feeding trial. Results: The TF treatment increased fecal VFA by 33% as compared with the control treatment (p = 0.07), suggesting stimulation of the hindgut fermentation. However, urinary N was not significantly reduced or shifted to fecal N, nor was slurry pH decreased. Accordingly, ammonia emissions were not mitigated. CR and CL treatments failed to enhance in vivo hindgut fermentation, as assessed by fecal VFA and purine bases. On the contrary, the reduction of CP digestibility in the CL treatment enhanced ammonia emissions from slurry. Conclusion: Dietary inclusion of cassava and tofu byproducts through an increase of dietary NSP from 10% to 15% might stimulate fecal VFA excretion but this does not guarantee a reduction in ammonia emissions from slurry, while its interaction with protein digestibility even might enhance enhanced ammonia emission.

• Oncology Letters
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• v.41 no.6
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• pp.3464-3474
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• 2019

The EF-hand calcium binding protein tescalcin (TESC) is highly expressed in various human and mouse cancer tissues and is therefore considered a potential oncogene. However, the underlying mechanism that governs TESC expression remains unclear. Emerging evidence suggests that TESC expression is under epigenetic regulation. In the present study, the relationship between the epigenetic modification and gene expression of TESC in gastric cancer was investigated. To evaluate the relationship between the methylation and expression of TESC in gastric cancer, the methylation status of CpG sites in the TESC promoter was analyzed using microarray with the Illumina Human Methylation27 BeadChip (HumanMethylation27_270596_v.1.2), gene profiles from the NCBI Dataset that revealed demethylated status were acquired, and real-time methylation-specific PCR (MSP) in gastric cancer cells was conducted. In the present study, it was demonstrated that the hypermethylation of TESC led to the downregulation of TESC mRNA/protein expression. In addition, 5-aza-2c-deoxycytidine (5'-aza-dC) restored TESC expression in the tested gastric cancer cells except for SNU-620 cells. ChIP assay further revealed that the methylation of the TESC promoter was associated with methyl-CpG binding domain protein (MBD)1, histone deacetylase (HDAC)2, and Oct-1 and that treatment with 5'-aza-dC facilitated the dissociation of MBD1, HDAC2, and Oct-1 from the promoter of TESC. Moreover, silencing of TESC increased MBD1 expression and decreased the H3K4me2/3 level, thereby causing transcriptional repression and suppression of cell survival in NCI-N87 cells; conversely, overexpression of TESC downregulated MBD1 expression and upregulated the H3K4me2 level associated with active transcription in SNU-638 cells. These results indicated that the differential expression of TESC via the modification status of the promoter and histone methylation controled cell survival in gastric cancer cells. Overall, the present study provided a novel therapeutic strategy for gastric cancer.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.22 no.2
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• pp.164-173
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• 2000

The p16 protein is a cyclin dependent kinase inhibitor that inhibits cell cycle progression from $G_1$ phase to S phase in cell cycle. Many p16 gene mutations have been noted in many cancer-cell lines and in some primary cancers, and alterations of p16 gene function by DNA methylation have been noticed in various kinds of cancer tissues and cell-lines. There have been a large body of literature has accumulated indicating that abnormal patterns of DNA methylation (both hypomethylation and hypermethylation) occur in a wide variety of human neoplasma and that these aberrations of DNA methylation may play an important epigenetic role in the development and progression of neoplasia. DNA methylation is a part of the inheritable epigenetic system that influences expression or silencing of genes necessary for normal differentiation and proliferation. Gene activity may be silenced by methylation of up steream regulatory regions. Reactivation is associated with demethylation. Although evidence or a high incidence of p16 alterations in a variety of cell lines and primary tumors has been reported, that has been contested by other investigators. The precise mechanisms by which abnormal methylation might contribute to carcinogenesis are still not fully elucidated, but conceivably could involve the modulation of oncogene and other important regulatory gene expression, in addition to creating areas of genetic instability, thus predisposing to mutational events causing neoplasia. There have been many variable results of studies of head and neck squamous cell carcinoma(HNSCC). This investigation was studied on 13 primary HNSCC for p16 gene status by protein expression in immunohistochemistry, and DNA genetic/epigenetic analyzed to determine the incidence, the mechanisms, and the potential biological significance of its Inactivation. As methylation detection method of p16 gene, the methylation specific PCR(MSP) is sensitive and specific for methylation of any block of CpG sites in a CpG islands using bisulfite-modified DNA. The genomic DNA is modified by treatment with sodium bisulfate, which converts all unmethylated cytosines to uracil(thymidine). The primers designed for MSP were chosen for regions containing frequent cytosines (to distinguish unmodified from modified DNA), and CpG pairs near the 5' end of the primers (to provide maximal discrimination in the PCR between methylated and unmethylated DNA). The two strands of DNA are no longer complementary after bisulfite treatment, primers can be designed for either modified strand. In this study, 13 paraffin embedded block tissues were used, so the fragment of DNA to be amplified was intentionally small, to allow the assessment of methylation pattern in a limited region and to facilitate the application of this technique to samlples. In this 13 primary HNSCC tissues, there was no methylation of p16 promoter gene (detected by MSP and automatic sequencing). The p16 protein-specific immunohistochemical staining was performed on 13 paraffin embedded primary HNSCC tissue samples. Twelve cases among the 13 showed altered expression of p16 proteins (negative expression). In this study, The author suggested that low expression of p16 protein may play an important role in human HNSCC, and this study suggested that many kinds of genetic mechanisms including DNA methylation may play the role in carcinogenesis.

• BMB Reports
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• v.57 no.2
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• pp.110-115
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• 2024

Alterations in DNA methylation play an important pathophysiological role in the development and progression of colorectal cancer. We comprehensively profiled DNA methylation alterations in 165 Korean patients with colorectal cancer (CRC), and conducted an in-depth investigation of cancer-specific methylation patterns. Our analysis of the tumor samples revealed a significant presence of hypomethylated probes, primarily within the gene body regions; few hypermethylated sites were observed, which were mostly enriched in promoter-like and CpG island regions. The CpG Island Methylator Phenotype-High (CIMP-H) exhibited notable enrichment of microsatellite instability-high (MSI-H). Additionally, our findings indicated a significant correlation between methylation of the MLH1 gene and MSI-H status. Furthermore, we found that the CIMP-H had a higher tendency to affect the right-side of the colon tissues and was slightly more prevalent among older patients. Through our methylome profile analysis, we successfully verified the methylation patterns and clinical characteristics of Korean patients with CRC. This valuable dataset lays a strong foundation for exploring novel molecular insights and potential therapeutic targets for the treatment of CRC.

• Korean Journal of Materials Research
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• v.15 no.10
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• pp.671-677
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• 2005

Ti and Ti alloys are known to have excellent corrosion properties, which is an important aspect for biocompability of these implants in human body. In our study, four types of samples (Cp-Ti, Ti-6Al-4V, $0.5wt.\%$ Fe-Ti and ECAP Ti) were tested for their apatite forming ability and corrosion properties. The micropolished samples were treated with 5M NaOH solution at $60^{\circ}C$ for 24 hours. Each samples was gently washed with distilled water and heat-treated at 600"C for 1 hour. The heat-treated samples were soaked in Simulated Body Fluid (SBF) solution at $36.5^{\circ}C$ in an incubator for different period of time. The test revealed that $0.5 wt.\%$ Fe-Ti showing faster apatite growth on the surface (7th day) compared to other samples. Polarization curve test (PCT) was also carried out to determine the corrosion resistance of each samples in SBF solution. ECAP-Ti showed highest corrosion resistance compared to any other samples. $0.5wt.\%Fe-Ti$ showed higher corrosion potential and corrosion current compared to other samples.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.37 no.3
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• pp.249-257
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• 2013

Rapid prototyping was used to design and develop a three-dimensional (3D) scaffold for tissue engineering application. In this study, the nozzle guide (TB-CP-HN, MUSASHI ENGINEERING, INC., JAPAN) used with the syringe of the polymer deposition system (PDS) was evaluated by measuring the scaffold line width and height. 3D scaffolds were fabricated using a biodegradable polymer called poly-caprolactone (PCL). The PCL polymer can be deposited from the needle of a syringe using a 200-${\mu}m$ precision nozzle, at a pressure of 600 kPa and temperature of $125^{\circ}C$. The advantages and improvements in this nozzle guide were addressed through washer scaffold fabrication. Overall, this research indicated that the fabrication of a complex-shaped scaffold using an enhanced polymer deposition system may have potential for tissue engineering.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.5
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• pp.747-751
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• 1999

The Hohenheim in vitro gas test was used to assess the nutritional value of some crop residues of known in vivo digestibility. The crop residues are groundnut shells (GNS) corn cobs (CC); cassava peels (CaP); unripe and ripe plantain peels (UPP, RPP) and citrus pulp/peels (CPP). Compared to other crop residues, crude protein (CP) content of CC was low. Except for CaP and CPP that had low neutral detergent fibre (NDF) and acid detergent fibre (ADF), other residues contained a high amount of cell wall constituents. Net gas production was significantly different among the crop residues (p<0.05). Gas production was highest in CPP followed by CaP. CC, UPP and RPP have the same volume of net gas production, while the least net gas production was in GNS. True dry matter (TDM) digestibility was significantly different (p<0.05) among the residues. GNS was the least in TDM digestibility. CaP, UPP and RPP had similar TDM digestibility values, while the highest TDM digestibility was obtained in CPP. OM digestibility was different among the residues (p<0.05). CaP and CPP had the same ME value while CC, UPP and RPP had close ME values and GNS the least in ME (p<0.05). The potential extent (b) and rate (c) of gas production were statistical different among the residues (p<0.05). The Hohenheim gas test gave high in vitro organic matter (OM) digestibility for CC, CaP, UPP and RPP and CPP. Fermentable carbohydrates and probably available nitrogen in the crop residues influenced net gas production. The results showed that crop residues besides, providing bulk are also a source of energy and fermentable products which could be used in ruminant livestock production in the tropics.