• Natural Product Sciences
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• v.15 no.4
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• pp.213-221
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• 2009

Longanae Arillus (the rind of fruits of Dimocarpus longan) has been consumed for the treatment of insomnia and anxiety in Asia. To provide further scientific basis to traditional uses of this fruit on insomnia, we evaluated the effects of methanol extract of Longanae Arillus (MELA) on the alteration of sleep architecture and electroencephalogram (EEG) power spectra in acutely and chronically restraint-stressed rats. Following postsurgical recovery, Polygraphic signs of sleep-wake activities were recorded for 24 h after MELA administration in rats. Rats in the acute stress and chronic stress were administered with MELA for 10 days. On the $8^{th},\;9^{th}\;and\;10^{th}$ day of MELA administration, the rats were stressed for 3 h once per day. On the $10^{th}$ day and 1 h after MELA administration, the rats were stressed once for 22 h in the chronic stress group. Acute and chronic stress induced alternations in cortex EEG recordings during non-rapid eye movement (NREM), rapid eye movement (REM) sleep and wakefulness. MELA shortened the total and REM sleep and increased the wakefulness in night time recording without changing daytime recordings. Chronic stress increased wakefulness and REM sleep, decreased total and NREM sleep in the daytime recording, and increased REM and decreased NREM sleep without changing total sleep and wakefulness in night time recording. These findings suggest that MELA ameliorated the alterations in REM and NREM sleep of acutely and chronically stressed rats via modulation of cortical ${\alpha}-$, ${\theta}-$ and ${\delta}-$ wave activity.

• Journal of Ginseng Research
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• v.34 no.1
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• pp.30-40
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• 2010

The present investigation was conducted to evaluate the regulation of sleep architecture by the red ginseng water extract (RGE) in acutely and chronically restraint stressed rats. Adult rats were fitted with sleep.wake recording electrodes. Following post-surgical recovery, rats were extensively habituated for freely moving polygraphic recording conditions. Polygraphic signs of sleep-wake activities were recorded for 24 h after RGE administration and induction of stress and were analyzed to understand the regulation of sleep architecture. Acute stress decreased wakefulness and increased total sleep, non-rapid eye movement (NREM) sleep, and rapid eye movement (REM) sleep in both the daytime and nighttime recording. RGE shortened the daytime NREM and REM sleep, without changing the wakefulness and total sleep. RGE increased nighttime wakefulness, and decreased total, NREM and REM sleep. Chronic stress increased wakefulness and decreased total sleep in the daytime recording, and increased REM and decreased NREM sleep in both the day and night time recording. RGE ameliorated chronic stress and induced alterations of REM and NREM sleep in the day and night time sleep architecture. Acute and chronic stress could also induce alternations in cortex electroencephalogram (EEG) recording during NREM, REM sleep and wakefulness. These findings suggest that RGE may modulate the sleep behavior in acutely and chronically stressed rats and the ameliorating effect of RGE on the sleep architecture may involve in modulation of $\alpha$-, $\theta$- and $\delta$- wave activities of the cortical EEG.

• Korean Journal of Veterinary Research
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• v.58 no.4
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• pp.201-209
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• 2018

Canine mammary tumors are among the most frequently observed cutaneous tumors in female dogs. Cancer stem cells (CSCs), referred to as tumor-initiating cells, are thought to have properties similar to normal stem cells such as the ability to self-renewal and to differentiate into various cell types. Biological understanding of CSCs and the critical pathways involved in their maintenance are important in research and therapy for mammary tumors. We conducted the present study on sphere formation from REM134 cells by using methylcellulose to produce tumorspheres on a large scale and compared the specific markers of the spheres-formed and plating-cultured REM134 cells. The results revealed that the tumorspheres cultured in methylcellulose had higher seeding density and improved morphology compared to those produced in normal sphere formation medium. Expression levels of stemness markers and CSC-related markers were higher in tumorsphere-forming cells than in plating-cultured cells. Subsequently, we transplanted the tumorsphere-forming and plating-cultured cells into female nude mice to examine their tumorigenic potential. Tumor volume increased rapidly in mice transplanted with tumorsphere-derived cells compared to plating-cultured cells. We observed a novel sphere-forming condition for REM134 cells and showed that REM134 cell tumorspheres can exhibit improved CSC properties.

• Proceedings of the Korea Society of Design Studies Conference
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• 2004.05a
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• pp.126-127
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• 2004

• Annals of Clinical Neurophysiology
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• v.16 no.2
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• pp.95-97
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• 2014

• Proceedings of the KWS Conference
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• 2001.05a
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• pp.205-207
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• 2001

• Sleep Medicine and Psychophysiology
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• v.18 no.1
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• pp.23-28
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• 2011

Objectives: REM sleep behavior disorder (RBD) has received little attention in epidemiologic studies. This study aimed to determine the prevalence of probable REM sleep behavior disorder (pRBD) in the elderly population and its clinical features. Methods: A random sample of 1,588 was selected from a roster of 14,050 elderly population living in Osan city. The subjects were asked to fill out the REM sleep behavior disorder screening questionnaire (RBDSQ). Subjects whose score were 5 or higher on RBDSQ underwent a diagnostic phase of person-to-person assessment by experts in RBD. Results: Among 1,588 subjects, 886 elderly subjects participated in the screening phase and 123 subjects were assessed in the diagnostic phase. Eleven subjects were diagnosed as having pRBD, so prevalence was 1.5% (95% CI=0.70-2.30%). The frequency of depression and cognitive decline was significantly increased in patients with pRBD compared to subjects without pRBD, and there was no difference in sleep disturbances between two groups. Conclusions: Probable REM sleep behavior disorder is not rare in the elderly but frequently under-recognized. More attention should be paid to evaluation and treatment of RBD.

• Korean Journal of Clinical Laboratory Science
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• v.39 no.3
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• pp.264-270
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• 2007

Obstructive sleep apnea syndrome (OSAS) is defined by sleep apnea with decreased oxygen saturation, excessive snoring with daytime sleepiness, and frequent awakening during the night time sleep. The present study was performed to investigate how apnea-hypopnea, that possibly causes breathing disturbance during sleep, can affect sleep pattern in patients with OSAS. We included 115 patients (92 men, 23 women) who underwent a polysomnography from January 2006 to May 2007. As the frequency of sleep apnea-hypopnea increases, the proportion of non-rapid eye movement (REM) sleep (p<0.001), and stage I sleep (p<0.001) increased, while that of stage II sleep (p<0.001), stage III and IV sleep (p<0.01), and REM sleep (p<0.05) decreased. Furthermore, sleep apnea-hypopnea was closely correlated with REM sleep (r=0.314, p<0.001), stage I sleep (r=0.719, p<0.001), stage II sleep (p=-0.342, p<0.05), stage III and IV sleep (r=-0.414, p<0.001), and REM sleep (r=-0.342, p<0.05). Stage I sleep could account for the 51% of the variance of apnea-hyponea. Our study shows sleep apnea-hypopnea affects sleep pattern in pattern with OSAS significantly, and the change of stage I sleep is the most important factor in estimating the disturbance of sleep pattern.

• Sleep Medicine and Psychophysiology
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• v.13 no.1
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• pp.5-10
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• 2006

Alcohol has extensive effects on sleep and daytime sleepiness. Alcohol has a sleep inducing effect and the effect of increased non-REM sleep and suppressed REM sleep during the first half portion of night sleep, but alcohol induces the effect of decreased non-REM sleep and increased light sleep and frequent awakenings and REM rebound during the second half portion of night sleep. Alcohol provokes chronobiological change such as the changes of amplitude or the phase shifts of hormones or core body temperature. The sleep disruption resulting from alcohol drinking may lead to daytime fatigue and sleepiness. The elderly are at particular in the increased risk of alcohol-related sleep disorders because they achieve higher levels of alcohol in the blood and brain than do younger adults after consuming an equivalent dose. Bedtime alcohol consumption among older adults may lead to unsteadiness if walking is attempted during the night, with increased risk of falls and injuries. Continued alcohol use for sleep induction often induces aggravation of insomnia, alcoholism or sleep related breathing disorders such as obstructive sleep apnea. Alcohol should not be used as substitution of sleep pill because of the dependence and tolerance for sleep inducing effect, and the sleep disruption produced by alcohol withdrawal.

• Journal of Distribution Science
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• v.17 no.9
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• pp.103-115
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• 2019

Purpose - We attempted to verify the level of ethics of firms achieving sustainable management from the aspect of reliability of accounting information. Specifically, we evaluated the effects of sustainable management on accruals-based earning management (AEM) and real earning management (REM). Research design, data, and methodology - We employed the issuance of sustainability reports in addition to the indices of social responsibility and environmental-management evaluation of the Korea Corporate Governance Service in order to measure sustainability management. AEM was measured using discretionary accruals and calculated using the operant Jones model. Specifically, REM was measured using the methodology suggested by prior studies. The sample of our study consisted of 1,418 years of public listed firms in the Korea Stock Exchange from 2015 to 2017. Results - First, the level of AEM in firms achieving sustainable management was lower than the other. Second, the level of REM in these firms was lower than the other. Nonetheless, another analysis showed that the level of governance control affects the level of earning management and that the levels of AEM and REM were generally lower in firms achieving sustainable management than the others. Conclusions - We expected that firms achieving external ethics tend to have a higher level of internal ethics than others.