• The Korean Journal of Physiology and Pharmacology
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• v.19 no.3
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• pp.203-210
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• 2015

AMP-activated protein kinase (AMPK) is a key regulator of energy metabolism. Previous studies have shown that activation of AMPK results in suppression of cardiac myocyte hypertrophy via inhibition of the p70S6 kinase (p70S6K) and eukaryotic elongation factor-2 (eEF2) signaling pathways. Epigallocatechin-3-gallate (EGCG), the major polyphenol found in green tea, possesses multiple protective effects on the cardiovascular system including cardiac hypertrophy. However, the molecular mechanisms has not been well investigated. In this study, we found that EGCG could significantly reduce natriuretic peptides type A (Nppa), brain natriuretic polypeptide (BNP) mRNA expression and decrease cell surface area in H9C2 cardiomyocytes stimulated with phenylephrine (PE). Moreover, we showed that AMPK is activated in H9C2 cardiomyocytes by EGCG, and AMPK-dependent pathway participates in the inhibitory effects of EGCG on cardiac hypertrophy. Taken together, our findings provide the first evidence that the effect of EGCG against cardiac hypertrophy may be attributed to its activation on AMPK-dependent signaling pathway, suggesting the therapeutic potential of EGCG on the prevention of cardiac remodeling in patients with pressure overload hypertrophy.

• The Korean Journal of Food And Nutrition
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• v.18 no.1
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• pp.4-10
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• 2005

Periodate-oxidized soluble starch increased pH stability of Aspergillus awamori a-glucosidase. After incubation for two hours, the enzyme in the absence of oxidized soluble starch was stable in the range of pH 3-7 at 40℃, pH 3-6 at 50℃ and the enzyme in the presence of oxidized soluble starch was stable in the range of pH 3-9 at 40℃, pH 3-8 at 50℃. At 60℃, the enzyme was stable in pH 3-6 regardless of the presence or absence of IO₄-oxidized soluble starch, but when IO₄-oxidized soluble starch existed in pH 5-6, remained activity of the enzyme increased 20% more than when it didn't exist. The enzyme modified with IO₄-oxidized soluble starch remained 70% of activity in pH 9, but native enzyme didn't remain, showing the increase of stability due to modification. In thermal stability, modified enzyme remained 12% at 50℃ and 7% at 80℃. But native enzyme remained 8% at 50℃ and didn't remain at more than 70℃. The result of HPLC analysis revealed the subunit of the enzyme at under pH 2 or over pH 9 was separated or the enzyme was denatured and conjugated. Protein structure of native enzyme was denatured by acidic and basic pH but was stable in the presence of IO₄-oxidized soluble starch.

• Food Science and Biotechnology
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• v.17 no.4
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• pp.883-887
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• 2008

The purpose of this study was to develop a new preparation process for chemical transformation of ginseng saponin glycosides to prosapogenins. Ginseng and ginseng extracts were processed under several treatment conditions using ascorbic acid solution. Treating with ascorbic acid at pH 2-3 and above $80^{\circ}C$ increased the ginsenoside $Rg_3$ content of samples to over 3% as compared to other pH levels and temperatures. In addition, ginseng and ginseng extracts that were processed under a high ascorbic acid solution treatment condition (pH 2.0, 5 hr) contained more ginsenoside $Rg_3$ (approximately 16 times) than those processed under a low ascorbic acid solution treatment condition (pH 3.0, 5 hr). The highest quantity of ginsenoside $Rg_3$ (3.434%) occurred when a sample of fine ginseng root extract (AG2-9) was processed with the ascorbic acid solution at pH 2.0 for 9 hr. However, there was no change in the amount of ginsenoside $Rg_3$ when fine ginseng root extracts were processed with ascorbic acid solution at pH 2.0 for over 9 hr. In conclusion, the results indicated that ascorbic acid treatment of ginseng extracts can produce a level of ginsenoside $Rg_3$ that is over 90-fold the amount found in commercial red ginseng.

• Genomics & Informatics
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• v.18 no.4
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• pp.42.1-42.9
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• 2020

Chromatin immunoprecipitation coupled with high-throughput DNA sequencing (ChIP-Seq) is a powerful technology to profile the location of proteins of interest on a whole-genome scale. To identify the enrichment location of proteins, many programs and algorithms have been proposed. However, none of the commonly used peak calling programs could accurately explain the binding features of target proteins detected by ChIP-Seq. Here, publicly available data on 12 histone modifications, including H3K4ac/me1/me2/me3, H3K9ac/me3, H3K27ac/me3, H3K36me3, H3K56ac, and H3K79me1/me2, generated from a human embryonic stem cell line (H1), were profiled with five peak callers (CisGenome, MACS1, MACS2, PeakSeq, and SISSRs). The performance of the peak calling programs was compared in terms of reproducibility between replicates, examination of enriched regions to variable sequencing depths, the specificity-to-noise signal, and sensitivity of peak prediction. There were no major differences among peak callers when analyzing point source histone modifications. The peak calling results from histone modifications with low fidelity, such as H3K4ac, H3K56ac, and H3K79me1/me2, showed low performance in all parameters, which indicates that their peak positions might not be located accurately. Our comparative results could provide a helpful guide to choose a suitable peak calling program for specific histone modifications.

• Journal of the Korean Wood Science and Technology
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• v.35 no.4
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• pp.21-28
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• 2007

To analyze the changes in pH and elemental content ratio of wood charcoal and in FT-IR spectra of their surfaces, wood charcoals carbonized from Pinus koraiensis were used. pHs of wood charcoals carbonized from Pinus koraiensis at 300 and $400^{\circ}C$ were 5-27 and 6.80, respectively, whereas they were between 9.25~10.35 for the wood charcoals manufactured between $500{\sim}900^{\circ}C$ From the changes in the elemental ratios of Pinus koraiensis wood charcoal by increasing carbonization temperature, carbon (C) contents increased by elevating the carbonization temperature with the decreasing in content ratios of O and H. The largest changes in the ratio was found between the carbonization temperature 400 and $500^{\circ}C$. Ratios of C, O, H of the wood charcoal manufactured at 300 and $400^{\circ}C$ were 67.7, 28.9, 3.0% and 72.2, 24.9, 2.5%, respectively, while those at $500{\sim}900^{\circ}C$ were between 83.3~90.5, 13.6~9.0, 2.7~0.3%. The surface functional groups of Pinus koraiensis wood charcoals were determined by comparison of FT-IR spectra of the wood powder and the wood charcoal carbonized with the wood powder. The functional groups on the surface of wood charcoals carbonized at 300 and $400^{\circ}C$ were considered to be acidic groups like Lactone, Lactol, Carboxylic acid, Carboxylic anhydride, whereas Pyrone types could be the major functional groups for the wood charcoals carbonized between 500 and $900^{\circ}C$.

• Journal of applied mathematics & informatics
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• v.17 no.1_2_3
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• pp.605-614
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• 2005

We show that an Artinian O-sequence $h_0,h_1,{\cdots},h_{d-1},h_d\;=\;h_{d-1},h_{d+l}\;>\;h_d$ of codimension 3 is not level when $h_{d-1}\;=\;h_d\;=\;d + i\;and\;h{d+1}\;=\;d+(i+1)\;for\;i\;=\;1,\;2,\;and\;3$, which is a partial answer to the question in [9]. We also introduce an algorithm for finding noncancelable Betti numbers of minimal free resolutions of all possible Artinian O-sequences based on the theorem of Froberg and Laksov in [2].

• Korean Journal of Food Science and Technology
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• v.29 no.2
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• pp.211-217
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• 1997

The physical and chemical stability of anthocyanins from a Korean pigmented rice variety was investigated at various conditions of pH, temperature, metal ion, sugar, organic acid and light. The anthocyanin pigments were relatively stable with half-lives of 36 days (pH 2.0) and 17 days (pH 3.0), while they were decomposed in a day at neutral and basic pH of 7.0 and 9.0 at $25^{\circ}C$. The anthocyanins also showed high thermal stability at pH 3.0; the half-lives were 7.4 hr, 23.6 hr and 96.3 hr at $95^{\circ}C,\;75^{\circ}C\;and\;50^{\circ}$, respectively. Addition of di- and tri-valent metal ions at pH 3.0 resulted in the increase of color intensity and stability throughout 21 days of storage periods at $25^{\circ}C$. Most sugars added accelerated the degradation of anthocyanin pigments, so that fructose showed the greatest degradation effect on the pigments. Addition of citric acid at pH 3.0 increased stability of anthocyanins, while tartaric acid decreased stability. The anthocyanins were very sensitive on light irradiation with a degradation half-life of 14 hr under 20,000 lux-light dosage at pH 3.0.

• YAKHAK HOEJI
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• v.50 no.6
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• pp.403-408
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• 2006

1-Amino-5,6-dimethoxyindan hydrochloride was synthesized from 3- (3,4-dirnethoxyphenyl)propionic acid by intramolecular Friedel-Crafts acylation, oximation with hydroxylamine, and reduction with an overall yield of 74%. 2-Amino-5,6-dimethoxyindan hydrochloride was synthesized from 3-(3,4-dirnethoxyphenyl)propionic acid by intramolecular Friedel-Crafts acylation, oximation with isoamylnitrite, reduction in NaOH and reaction with HCI to form 5,6-dimethoxy-2-indanone, which was reacted with hydroxylamine and reduced with an overall yield of 42%. 5,6-Dimethoxyindan-1,2-dione-2-oxime, which was catalytically hydrogenated to afford cis-, and trans-1-amino-5,6-dimethoxyindan-1-ol as 3 : 1 ratio. This mixture was treated with Li and reacted with chloroacetyl chloride. Cis isomer was acylated and cyclized to synthesize rir -( ${\pm}$ )-7,8-dimethoxy-4,4a,5,9b-tetrahydroindeno[1,2-b][1,4]oxazin-3(2H)-one, but trans isomer was just acylated to form amide.

• Journal of Korean Biological Nursing Science
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• v.16 no.2
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• pp.141-149
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• 2014

Purpose: The purpose of this study was to compare the effects of gargling with A-Solution and 0.9% normal saline on xerostomia, halitosis, and salivary pH among nursing students. Methods: The study design was a randomized, controlled trial. The experimental group received oral gargling treatment for 15 seconds with A-solution while the control group received oral gargling treatment for the same time with 0.9% normal saline. Outcome variables were measured at baseline, 60 minutes, and 120 minutes. Results: The groups were homogeneous in general characteristics, and the outcome variables before the treatment between the experimental group and the control group. 1) There were no significant differences in xerostomia, halitosis, and salivary pH between the two groups. 2) There were no significant differences in xerostomia, halitosis, and salivary pH based on the time. 3) There were significant interactions between group and time in subjective halitosis (F=3.766, p=.034) only. Conclusion: These findings indicate that oral gargling with Aroma solution and 0.9% normal saline could have the same effect of reducing xerostomia and halitosis in nursing students.

• Korean Chemical Engineering Research
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• v.46 no.3
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• pp.545-549
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• 2008

The surface characteristics of calcined ${\gamma}-Al_2O_3$ particles as well as ${\gamma}-AlO$(OH) sol particles were controlled by aging in the boehmite sol preparation. As a result of the study, the IEPs of ${\gamma}-AlO$(OH) particles were decreased from pH 9.25 to pH 8.70 and those of the calcined ${\gamma}-Al_2O_3$ particles were decreased from pH 9.90 to pH 8.86 by the increase of the aging times. As a result of the acidic and basic characterization of the calcined ${\gamma}-Al_2O_3$ particles by the aging, the amount of acid sites was decreased from 0.1367 mmol/g to 0.0783 mmol/g by the increase of the aging times and Hammett acidity, $H_o$ was showed the acidic strength of 4.8 or above. On the other hand, the amount of basic sites was decreased from 0.4399 mmol/g to 0.3074 mmol/g by the increase of the aging times. Based on these results, we proposed the fact that the aging step in the sol-gel process was an important step to control the surface characterization of ${\gamma}-Al_2O_3$ particles including acidity and basicity.