• Natural Product Sciences
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• v.10 no.2
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• pp.74-79
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• 2004

Dietary flavonoids are currently receiving considerable attention in developing novel cancer-preventive approaches because of their potential capacities to actively induce apoptosis of cancer cells. In our previous report, a flavonoid fraction, which consisted mainly of protocatechuic acid, fustin, fisetin, sulfuretin, and butein and named RCMF (RVS chloroform-methanol fraction), was prepared from a crude acetone extract of Rhus verniciflua Stokes (RVS) that is traditionally used as food additive and herbal medicine. In this study, we evaluated the effects of the RCMF on cell proliferation and apoptosis using SV40-transformed tumorigenic hepatocytes, BNL SV A.8. Tritium uptake assay showing the proliferative capacity of the cells was strongly suppressed in the presence of RCMF. This anti-proliferative effect was further confirmed through trypan blue exclusion. RCMF-mediated suppression of cell growth was verified to be apoptotic, based on the increase in DNA fragmentation, low fluorescence intensity in nuclei after propidium iodide staining, and the appearance of DNA laddering. Collectively, this study demonstrated that RCMF can be approached as a potential agent that is capable of significantly inhibiting cell growth of hepatic cancer cells.

• Microbiology and Biotechnology Letters
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• v.18 no.6
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• pp.566-570
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• 1990

Regulation of $\beta$ -galactosidase formation was studied with Lactobacillus sporogenes. Synthesis of the enzyme was effectively induced by isopropyl- $\beta$-D-thiogalactopyranoside (IPTG) or galactose, and to a much lower level by lactose. When 15 mM glucose was added at the different intervals to the cultures that had been in contact with IPTG, the same levels of inhibition of the enzyme synthesis were observed (approximately one-third the differential rate of a control culture without glucose). This suggests that glucose did not interfere with the entry of the inducer into the cells, but interfere with the formation of $\beta$ -galactosidase through catabolite repression. The glucose inhibitory effect was not overcome by adding CAMP or cGMP to the culture media.

• Korean Journal of Pharmacognosy
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• v.27 no.2
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• pp.155-158
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• 1996

The methanol extract of Albizzia julibrissin Durazz. (Leguminosae) was successively partitioned into dichloromethane, ethylacetate, butanol (BuOH) and water fractions, and the effects of the each solvent extract on catecholamine biosynthesis in PC12 cells were investigated. Among them, the BuOH fraction $(5{\mu}g/ml\;medium)$ showed 68.8% and 63.6% inhibition on dopamine and norepinephrine content in PC12 cells, respectively. Tyrosine hydroxylase (TH) activity was also reduced markedly by treatment of the BuOH fraction (41.8% inhibition at $5{\mu}g/ml$ in the medium). Each solvent fraction did not show cytotoxicity towards PC12 cells by trypan blue exclusion test. This result suggests that the BuOH fraction has an inhibitory effect on catecholamine biosynthesis by reducing TH activity in PC12 cells.

• Speech Sciences
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• v.8 no.1
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• pp.143-157
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• 2001

This paper focused on glottal parameters contributing to the perception of loud voices because energy of a voice is not the only effective factor. We used a formant synthesizer to synthesize loud voices. We divided F0 tilt (the tilt of F0 contour), SQ (Speed Quotient), OQ (Open Quotient) and TL (spectral Tilt Level) into three levels to get different combinations with default values for the other synthesizer parameters. Analysis of listening tests indicated that F0 tilt, SQ, OQ and TL in descending order had significant influence on the perception of loud voices. F0 tilt had a far more significant effect than the others. The influence of SQ increased greatly with the exclusion of F0 tilt as a factor. The interaction between parameters was not significant.

• Membrane Journal
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• v.13 no.1
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• pp.29-36
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• 2003

A characterization of the permeation and separation using single salt solution was carried out with charged composite membranes. Various charged composite membranes were fabricated by blending an ionic polymer with a nonionic polymer in different ratios. In this study, sodium alginate, chitosan and poly(vinyl alcohol) were employed as anionic, cationic and nonionic polymers, respectively. The permeation and separation behaviors of the aqueous salt solutions have been investigated through the charged composite membranes with various charge densities. As the content of the ionic polymer increased in the membrane, the hydrophilicity of the membrane increased, and pure water flux and the solution flux increased correspondingly, indicating that the permeation performance through the membrane is determined mainly by its hydrophilicity. Electrostatic interaction between the charged membrane and ionic solute molecules, that is, Donnan exclusion, was observed to be attributed to salt rejection to a greater extent, and molecular sieve mechanism was effective for the separation of salts under a similar electrostatic circumstance of solutes.

• Proceedings of the Optical Society of Korea Conference
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• 2001.02a
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• pp.50-51
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• 2001

We investigate the effect of resonantly excited excitons on the optical-absorption of the n=1hh and n=2hh exciton resonances in GaAs quantum wells. Under quasistationary excitation condition using the pump and probe beam at tow temperature, we report the first observation of long range Coulomb screening by two dimensional exciton-exciton interaction, and discriminate unambiguously exciton bleaching between by long range Coulomb screening and the Pauli exclusion principle. (omitted)

• Proceedings of the KIEE Conference
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• 2000.07d
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• pp.2311-2313
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• 2000

In this paper, we consider $H^{\infty}$ optimal Kalman filter problems for linear weakly coupled stochastic systems. We introduce a decomposition for the systems of the Hamiltonian form, which plays an important role of exclusion of ill-condition by ${\varepsilon}$-effect and the parallel computation possibility. It is shown that the algebraic Riccati equation of the weakly coupled $H^{\infty}$ optimal Kalman filter problem is decoupled into completely independent reduced-order, well-defined, two suboptimal Kalman filters.

• The Korean Journal of Gastroenterology
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• v.72 no.5
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• pp.252-257
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• 2018

This guidance is an updated version of the irritable bowel syndrome (IBS) guidelines based on evidence-based medicine. IBS is a common chronic gastrointestinal syndrome that occurs in approximately 10% of the population and causes chronic abdominal pain as well as bowel habit changes, such as stool frequency or consistency. The final diagnosis of IBS is based on the exclusion of organic diseases that would explain the symptoms and the absence of endoscopic abnormalities. IBS can reduce the quality of life and cause a major disease burden, such as repeated examinations and continuous drug use, by mistaking organic diseases including malignancy. The major changes are as follows: 1) when to perform a colonoscopy under the impression of IBS; 2) effect of a low-fermentable oligosaccharides, disaccharides, monosaccharides, and polyol diet; 3) impact of probiotics in IBS; and 4) role of antibiotics in IBS. The Korean Society of Neurogastroenterology and Motility recently updated these guidelines to support physicians for qualified medical services and reduce the socioeconomic burden of IBS.

• Journal of The Korean Society of Integrative Medicine
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• v.11 no.4
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• pp.1-15
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• 2023

Purpose : This study investigates the effectiveness of digital therapy for stroke patients in Korea. Methods : A comprehensive database search was performed using KCI, Science on, e-article, RISS, KISS and Korea OpenMed databases for randomized controlled trials (RCTs) that studied the effects of digital therapy on patients who had a stroke. This study includes RCTs published from January 2000 to July 15, 2022, which fulfilled the inclusion and exclusion criteria. A total 697 studies were screened and 30 studies were included in the final analysis. Methodological quality was assessed with the Cochrane's RoB (risk of bias) tool. Meta-analysis was performed using CMA 4.0 software. Results : A total of 56 effect sizes were calculated from the 30 selected studies. As a result of the analysis, the overall effect size of digital therapy was .59 (95 % CI=.43-.74). When classified according to type of intervention, VR (virtual reality) (g=.58, 95 % CI=.40-.75), and CACR (computer assisted cognitive rehabilitation) (g=.62, 95 % CI=.30-.95) were statistically significant. VR showed medium to large effect sizes in cognitive function (g=.78, 95 % CI=.20-1.37), psychosocial function (g=.63, 95 % CI=.20-1.07), and physical function (g=.61, 95 % CI=.38-.83). In the CACR, there was a large effect size in cognitive function (g=.84, 95 % CI=.52-1.15), but there was no significant difference in psychosocial function. Also, there was no significant difference between the two interventions in activities of daily living and no significant difference in the effect size of both interventions according to the intervention session. Furthermore, medium to large effect sizes were found for subacute and chronic stroke patients according to the duration of disease. Conclusion : This study presents evidence that digital therapy has a positive effect on various functions of stroke patients in Korea. The researchers expect to actively accept the new paradigm of digital therapy and continue to apply digital therapy in clinical practice.

• The Journal of Internal Korean Medicine
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• v.25 no.2
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• pp.214-223
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• 2004

The study examines the anti-cancer effects of the hot water extract of Mylabris phalerata(MP) using SNU-C5 cell lines. Microscopic analysis showed that 12 hours after MP treatment, the number of dead cells increased prominently. Significant cell death was observed 12, 24, and 48 hours after MP treatment through trypan blue exclusion testing. This suggests that MP is time-dependently cytotoxic. Mitotracker Red CMXRos staining and flowcytometry revealed that MP decreased mitochondrial membrane potentials. The absence of peaks on PI staining showed that DNA damage occurred in MP treated cells. Taken together, measurements suggest that MP has a strong anti-cancer effect on SNU-5 cell lines, and that this is likely to be due to the destruction of mitochondria and DNA damage.