• Sleep Medicine and Psychophysiology
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• v.19 no.1
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• pp.11-17
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• 2012

Objective: Among various methods developed to quantitatively explore electroencephalograms (EEG), we focused on a wavelet method that was known to yield robust results under nonstationary conditions. The aim of this study was thus to introduce the wavelet method and demonstrate its potential use in clinical sleep studies. Method: This study involved artificial EEG specifically designed to validate the wavelet method. The method was performed to obtain time-dependent spectral power and phase angles of the signal. Synchrony of multichannel EEG was analyzed by an order parameter of the instantaneous phase. The standard methods, such as Fourier transformation and coherence, were also performed and compared with the wavelet method. The method was further validated with clinical EEG and ERP samples available as pilot studies at academic sleep centers. Result: The time-frequency plot and phase synchrony level obtained by the wavelet method clearly showed dynamic changes in the EEG waveforms artificially fabricated. When applied to clinical samples, the method successfully detected changes in spectral power across the sleep onset period and identified differences between the target and background ERP. Conclusion: Our results suggest that the wavelet method could be an alternative and/or complementary tool to the conventional Fourier method in quantifying and identifying EEG and ERP biomarkers robustly, especially when the signals were nonstationary in a short time scale (1-100 seconds).

• Clinical and Experimental Pediatrics
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• v.53 no.4
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• pp.579-584
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• 2010

Purpose : The number of the repatriated Korean students who had overseas study at early ages is increasing. They received foreign education, they can speak international languages, but they have many difficulties in articulation and intonation of the Korean language. This study aims to measure closure and aspiration duration, length of consonants, length of subsequent vowels, and ratio of consonants against subsequent vowels in vowel-consonant-vowel (VCV) syllables. Methods : This study compares the acoustic and phonetic characteristics of repatriated and native students, the ratio of articulation error of Korean plosives, the closure and aspiration duration, and the ratio of the aspiration duration against the closure duration. Results : The ratio of articulation error of Korean plosives between repatriated and native students is 19% and 2%, respectively. The closure duration was significantly longer in repatriated students than in native students. The aspiration duration was significantly longer in repatriated students than in native students. No difference was found in the ratio of aspiration duration against closure duration between the native and repatriated students. Conclusion : This study can be a good reference for estimating the phonetic difficulties of Korean elementary students who had overseas study at early ages.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.13
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• pp.5349-5357
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• 2015

Background: Breast cancer is the most common cancer and the leading cause of cancer mortality among women of all ethnic and age groups in Malaysia. Delay in seeking help for breast cancer symptoms is preventable and by identifying possible factors for delayed diagnosis, patient prognosis and survival rates could be improved. Objectives: This narrative review aimed to understand and evaluate the level of in-depth breast cancer knowledge in terms of clinical breast examination and breast self-examination, and other important aspects such as side-effects and risk factors in Malaysian females. Since Malaysia is multicultural, this review assessed social perceptions, cultural beliefs and help-seeking behaviour in respect to breast cancer among different ethnic groups, since these may impinge on efforts to 'avoid' the disease. Materials and Methods: A comprehensive literature search of seven databases was performed from December 2015 to January 2015. Screening of relevant published journals was also undertaken to identify available information related to the knowledge, perception and help-seeking behaviour of Malaysian women in relation to breast cancer. Results: A total of 42 articles were appraised and included in this review. Generally, women in Malaysia had good awareness of breast cancer and its screening tools, particularly breast self-examination, but only superficial in-depth knowledge about the disease. Women in rural areas had lower levels of knowledge than those in urban areas. It was also shown that books, magazines, brochures and television were among the most common sources of breast cancer information. Delay in presentation was attributed mainly to a negative social perception of the disease, poverty, cultural and religion practices, and a strong influence of complementary and alternative medicine, rather than a lack of knowledge. Conclusions: This review highlighted the need for an intensive and in-depth breast cancer education campaigns using media and community health programmes, even with the existing good awareness of breast cancer. This is essential in order to avoid misconceptions and to frame the correct mind-set about breast cancer among women in Malaysia. Socio-cultural differences and religious practices should be taken into account by health care professionals when advising on breast cancer. Women need to be aware of the risk factors and symptoms of breast cancer so that early diagnosis can take place and the chances of survival improved.

• Development and Reproduction
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• v.13 no.3
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• pp.163-172
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• 2009

Some organotin compounds such as butyltins and phenyltins are known to induce impo-sex in various marine animals and are considered to be endocrine disruptors. In this study, the effect of organotins on follicular steroidogenesis in amphibians was examined using ovarian follicles of Rana dybowskii and Rana catesbeiana. Isolated follicles were cultured for 6 or 18 h in the presence and absence of frog pituitary homogenate (FPH) or various steroid precursors, and the levels of product steroids in the culture media oassay. Among the butyltin compounds, tributyltin (TBT) strongly and dose-dependently inhibited the FPH-induced synthesis of pregnenolone ($P_5$) and progesterone ($P_4$) by the follicles. TBT also strongly suppressed the conversion of cholesterol to $P_5$ and partially suppressed the conversion of $P_5$ to $P_4$. A high concentration of dibutyltin (DBT) also inhibited steroidogenesis by the follicles while monobutyltin and tetrabutyltin had negligible effects. The toxic effect of TBT or DBT was irreversible and a short time of exposure (30 min) was enough to suppress steroidogenesis. All the phenyltin compounds significantly inhibited FPH-induced $P_5$ synthesis by the follicles. The effective dose of 50% inhibition by diphenyltin was $0.04\;{\mu}M$ and those of monophenyltin and triphenyltin were $0.24\;{\mu}M$ and $0.3\;{\mu}M$, respectively. However, none of the phenyltin compounds significantly suppressed the conversion of $P_4$ to $17{\alpha}$-hydroxyprogesterone ($17{\alpha}$-OHP) (by $17{\alpha}$-hydroxylase), $17{\alpha}$-OHP to androstenedione (AD) (by $C_{17-20}$ lyase), or AD to testosterone by the follicles. Taken together, the data show that among the steroidogenic enzymes, P450scc in the follicles is the most sensitive to organotin compounds and that an amphibian follicle culture system can be a useful screening model for endocrine disruptors.

• Microbiology and Biotechnology Letters
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• v.43 no.2
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• pp.97-104
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• 2015

Vinegar is a widely used acidic seasoning and can be manufactured using various methods and bases, including cereals, wheat, and fruits. Most studies on vinegar have been conducted to evaluate its antioxidant activity. In the present study, fermented dark vinegar (FDV) produced from unpolished rice was examined for its antimicrobial activity, biochemical content, including the amounts of sugar, total soluble sugar, organic acid, and free amino acids, and pH and physiological activity. The antimicrobial efficiency of FDV was assessed using the paper disc-agar diffusion method. FDV exhibited strong antimicrobial activity against the pathogenic bacteria and yeast strains that were tested. In fact, the activity of FDV was shown to be higher than that of the commercial antibiotics carbenicillin (50 µg/ml) and tetracycline (50 µg/ml) against Staphylococcus aureus, Escherichia coli, Listeria monocytogenes, Pseudomonas aeruginosa, Salmonella typhimurium, Yersinia enterocolitica, and Lodderomyces elongisporus. The antioxidant activity of FDV and ascorbic acid was evaluated. Using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging method, we found that FDV has the highest activity of the antioxidants. After spreading FDV onto tryptic soy broth and yeast extract-peptone-dextrose agar media, the microbial strains were isolated and characterized through physiological and biochemical analysis. Based on 16S ribosomal DNA sequence analysis, the isolated microorganisms exhibited a close similarity to Acetobacter papayae, Acetobacter pasteurianus, and Acetobacter peroxidans.

• The Korean Journal of Food And Nutrition
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• v.25 no.4
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• pp.941-950
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• 2012

In order to develop new physiologically active polysaccharides from persimmon leaves, two different crude polysaccharides were prepared using hot water (PLW-0) and pectinase digestion (PLE-0) and their immuno-stimulating activities were estimated. PLW-0 and PLE-0 showed similar sugar compositions with 15 different sugars, including rarely observed sugars in general polysaccharides such as 2-O-methyl-fucose, 2-O-methyl-xylose, apiose, aceric acid, 3-deoxy-D-manno-2-octulosonic acid, and 3-deoxy-D-lyxo-2-heptulosaric acid, but the uronic acid content of PLE-0 was lower than that of PLW-0 caused by pectinase treatment. Both PLW-0 and PLE-0 showed potent anti-complementary activity in a dose-dependent manner which was similar to a known immuno-stimulating polysaccharide, PSK, from Coriolus versicolor. The activity of PLE-0 at a low concentration ($100{\mu}g/m{\ell}$) was higher than that of PLW-0. In an in vitro cytotoxicity analysis, PLW-0 and PLE-0 (up to $1,000{\mu}g/m{\ell}$) did not affect the growth of peritoneal macrophages and Colon 26-M3.1 carcinoma cells. In contrast, they enhanced lymphocyte proliferation activity. Peritoneal macrophages stimulated with PLW-0 and PLE-0 produced various cytokines, such as IL-6 and IL-12. However, PLE-0 was more effective on the cytokine production. Intravenous administration of PLW-0 and PLE-0 significantly augmented natural killer (NK) cell cytotoxicity against Yac-1 tumor cells 3 days after the treatment of polysaccharide fractions. But NK cells obtained from the PLE-treated group showed higher tumoricidal activity even at a low dose of $40{\mu}g$/mouse. In experimental lung metastasis of Colon 26-M3.1 carcinoma cells, prophylactic administration of PLW-0 and PLE-0 significantly inhibited lung metastasis in a dose-dependent manner and PLE-0 was more effective on the inhibition of cancer metasasis. The results lead us to conclude that the pectinase-treated process is indispensable to preparing polysaccharides with higher immune-stimulating activity from persimmon leaves.

• Korean Journal of Food Science and Technology
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• v.37 no.2
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• pp.178-182
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• 2005

Basic optimal extraction condition and stability data were determined for prediction of usefulness of olive leaf as functional food material. Solid contents of olive leaf extracts increased with increasing extraction temperature and ethanol content, and was the highest (38%) under $85^{\circ}C$, 80% ethanol, and 5 hr treatment conditions, Total phenol contents and electron-donating abilities of olive leaf extracts also increased with Increasing ethanol content, and were the highest under $25^{\circ}C$, 80% ethanol, and 1 hr treatment conditions, then slightly decreased during storage at $25,\;55,\;and\;85^{\circ}C$. Olive leaf extract showed high stability under acidic storage condition, while low under alkalic condition.

• Food Science and Preservation
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• v.17 no.3
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• pp.343-350
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• 2010

Cheongkukjang was prepared by addition of medicinal herb powder (from Lentinus edodes, Codonopsis lanceolata BENTH et HOOK, or Houttuynia cordata THUNB) to improve Cheongkukjang quality and functional properties. Redness and yellowness (measured using Hunter’s color values) increased with increasing amounts of medicinal herb powder, whereas lightness (the third Hunter's color value) and pH decreased. Crude protein and lipid levels of Cheongkukjang decreased with increasing amounts of added medicinal herb powder, whereas powder addition did not affect either the moisture or crude ash content of Cheongkukjang. The major organic acids of Cheongkukjang were lactic acid, acetic acid, succinic acid, and citric acid, and acid levels increased as the proportion of medicinal herb powder in the Cheongkukjang preparation increased. The major amino acids of Cheongkukjang were glutamic acid, aspartic acid, leucine, arginine, and lysine and the principal fatty acids were linoleic acid, oleic acid, palmitic acid, and linolenic acid. Addition of medicinal herb powder to Cheongkukjang increased both crude saponin and quercetin contents. Sensory scores of Cheongkukjang containing 2% (w/v) medicinal herb powder were optimal in terms of both quality characteristics and sensory evaluation.

• Korean Journal of Food Science and Technology
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• v.37 no.3
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• pp.508-512
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• 2005

Ginsenoside composition and contents of Korean white and taegeuk ginsengs were investigated to establish Chinese pharmaceutical standards for import of Korean ginseng. Total ginsenoside-Rg1, Re, and Rb1 of all Korean white and taegeuk ginseng samples were higher than guideline of Chinese standard of 0.4%, $Mean{\pm}S.D.$ values of Rg1, Re, and Rb1 of Korean white ginseng were $232.7{\pm}110.2,\;235.3{\pm}101.5,\;and\;280.1{\pm}121.3\;mg%$, respectively. Ratio of Rg1 to Re of Korean white ginseng was 1.02. $Mean{\pm}S.D.$ values of Rg1, Re, and Rb1 of Korean taeguek ginseng were $262.1{\pm}127.2,\;213.1{\pm}55.7,\;and\;279.9{\pm}92.1\;mg%$, respectively.

• Food Science and Preservation
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• v.18 no.2
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• pp.149-155
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• 2011

Cheonggukjang tablet was prepared by addition of medicinal herb extracts (from Lentinus edodes, Codonopsis lanceolata, or Houttuynia cordata Thunb.) to improve its quality and functional properties. Lightness and yellowness (measured using Hunter's color values) were generally increased with increasing amount of medicinal herb extracts, whereas pH decreased. In proximate composition, the levels of crude protein, lipid and fiber levels of Cheonggukjang tablet decreased with increasing amount of added medicinal herb extracts, whereas moisture and crude ash were increased. The major amino acid of Cheonggukjang tablet were glutamic acid, aspartic acid, leucine and the principal fatty acids of Cheonggukjang tablet were linolenic acid, linoleic acid and palmitic acid, respectively. Hardness levels of Cheonggukjang tablet decreased with increasing amounts of added medicinal herb extracts. The Cheonggukjang tablet added with medicinal herb extracts increased both crude saponin and quercetin contents. Sensory score of Cheonggukjang tablet containing 20% (w/v) medicinal herb extracts were optimal in terms of both quality characteristics and sensory evaluation.