• Journal of Biomedical Engineering Research
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• v.44 no.1
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• pp.33-40
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• 2023

Transcutaneous auricular vagus nerve stimulation (taVNS) is known to be effective in improving symptoms of numerous diseases such as depression and epilepsy by increasing vagus nerve activity through electrical stimulation. The purpose of this study is to investigate the effect of vagus nerve stimulation on the activity of autonomic nervous system and the changes in postprandial blood glucose levels. Seven healthy adults participated in a non-invasive transcutaneous auricular vagus nerve stimulation experiment. taVNS (25 Hz, 200 ㎲, biphasic pulse) was applied to the cymba concha (taVNS group) or the earlobe (Sham-taVNS group) of the left ear. As autonomic nervous system signals, skin conductance level, skin temperature, and heart rate were recorded during the application of taVNS. Postprandial blood glucose changes due to food intake were recorded at 5 min intervals for 25 minutes after taVNS or sham-taVNS. The taVNS showed a significantly lower skin conductance level than the shamtaVNS (p < 0.05). The increase rate of postprandial blood glucose was significantly lower in the taVNS than in the sham-taVNS (p < 0.05). These results showed that taVNS reduced the activity of the sympathetic nerve system and alleviated early rise in postprandial blood glucose. Although further studies in diabetic patients are needed, this study suggest that taVNS has a potential for clinical use to improve postprandial blood glucose.

• Research in Vestibular Science
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• v.17 no.4
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• pp.160-166
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• 2018

Objectives: This study was conducted to assess the current management status of the vestibular function test laboratories in Korea. Methods: Questionnaire about the management status of the vestibular function test laboratories was sent by email to the entire members of the Korean Balance Society. The contents of questionnaire included situation of employees who perform the tests, the types of vestibular function tests and equipment, frequency of the test and types of dizziness related questionnaires. Results: Forty-nine hospitals and clinics responded. All the 49 respondents answered that they have videonystagmography. Spontaneous nystagmus analysis by videonystagmogrphy was the most frequently tests for patients with dizziness. Questionnaires for dizziness were used by 27 respondents (55.1%) for initial evaluation of the dizziness patients. The Korean version of dizziness handicap inventory was the most frequently used dizziness related questionnaire. Conclusions: We analyzed the current management status of vestibular function test laboratories to comprehend the present condition of the vestibular function test. We think that these results will help to provide a standard for laboratory operations and prepare for the education, focusing on high-demand tests.

• TTA REPORT
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• v.5 no.2 s.18
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• pp.18-31
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• 1993

국제 전기통신 연합(ITU)에서는 각국의 전기통신 관련 자료를 모아 지역별로 전기통신에 관한 지표 자료집을 발간하였다. 이 자료집은 유럽, 구소련, 미주, 아랍, 아프리카, 아시아$\cdot$태평양 등 6개 지역으로 구분하여 각 지역에 해당된 국가별로 1981년부터 10년동안의 각국의 전기통신에 관련된 자세한 정보를 싣고 있다. 각각의 자료집에는 해당 지역의 ITU 회원국들의 지난 10년간 공중통신과 관련된 각종 정보들을 도표와 그래프를 이용하여 알기 쉽고 일목 요연하게 잘 설명해 주고 있다. 아시아와 아프리카에 관한 자료는 올 1/4분기 안에 발행될 예정에 있어 아직 자료를 입수하지 못하였으나 다른 4개 지역에 대한 ITU 발간 자료를 수집하여 전기통신 현황에 관한 통계의 참고자료로 삼고 있다. 이들 책자를 통해 나타난 바를 지역별로 간단히 요약해 보자

• 대한상한금궤의학회지
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• v.12 no.1
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• pp.81-89
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• 2020

Objective: This case report presents the effect of Oryeong-san on vasovagal syncope. The patient was diagnosed with Grater Yang disease based on Shanghanlun provisions. Methods: According to the disease pattern identification diagnostic system based on Shanghanlun provisions (DPIDS), we diagnosed the patient as presenting Greater Yang disease. The patient was treated with Oryeong-san for 45 days. The change in symptoms was estimated based on VAS. Results: After treatment, the patient's VAS score from 10 to 0 and he was completely cured. Conclusions: This case study shows the effectiveness of using Oryeong-san on vasovagal syncope according to DPIDS.

• Clinical and Experimental Pediatrics
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• v.52 no.7
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• pp.798-803
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• 2009

Purpose : We aimed to examine the effectiveness of the head-up tilt test (HUT) for the diagnosis of syncope or presyncope in children and adolescents. Methods : HUT results and clinical features of 160 children and adolescents with syncope or presyncope were studied from May 2003 through March 2008 at the Chonbuk National University Hospital. The children and adolescents were subjected to $70^{\circ}$ HUT for 45 minutes. The testees were divided into 2 groups: group I (children) comprising 39 children in the age range 7-12 years (mean, $10.59{\pm}1.60$ years) and group II (adolescents) comprising 121 adolescents in the age range 13-20 years (mean, $15.93{\pm}2.28$ years). Positive result rates of the HUT and types of hemodynamic response to the test in the 2 groups were compared. Results : Of the 160 testees, 92 (57.5%) showed positive HUT results; they showed 3 patterns of response to tilting. Twelve patients showed a predominantly vasodepressor response; 10 patients showed a cardioinhibitory response; and 70 patients showed a mixed response. The positive result rates were 43.6% (17/39) and 62.0% (75/121) in groups I and II, respectively. Mixed response was the predominant positive hemodynamic response in both the groups. Conclusion : The HUT is a useful diagnostic tool for evaluating the condition of pediatric patients, including adolescents, with syncope. Further, it may be considered as the first step for evaluating the condition of such patients.

• Sleep Medicine and Psychophysiology
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• v.11 no.2
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• pp.100-105
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• 2004

Objectives: Major depression is associated with an increased risk of cardiovascular mortality. One possible explanation for this association is that major depression influences autonomic neurocardiac regulation. However, previous studies on the relationship between heart rate variability (HRV) and major depression have revealed conflicting results. The purpose of this study is to clarify that major depressive patients compared to healthy controls show a reduction in HRV as an expression of reduced modulation of vagal activity to the heart. Methods: According to DSM-IV, the time and frequency domain HRV indices (5-min resting study) of 30 patients with major depressive disorder were compared with those of 30 healthy controls. Standardized HRV tests enable quantitative estimation of autonomic nervous system function. Results: After controlling for age and gender, subjects with major depression showed a higher heart rate and significantly lower modulation of cardiovagal activity compared to controls. The total power (TP) band, very low frequency (VLF: 0.003-0.04 Hz) band, low frequency (LF: 0.04-0.15 Hz) band, and high frequency (HF: 0.15-0.4 Hz) band were significantly reduced in subjects with major depression compared to control subjects. Conclusion: Patients with major depression may suffer from functional disturbances in the interaction between the sympathetic and parasympathetic autonomic systems.

• The Journal of Internal Korean Medicine
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• v.38 no.2
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• pp.240-245
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• 2017

Objectives: The purpose of this clinical case report is to describe the efficacy of Korean medicine in the treatment of vasovagal syncope. Methods: The patient was treated with acupuncture, pharmacopuncture, and herbal medicine. The symptoms (headache, palpitation, sweating, flushing, weakness, coldness) of the patient were observed. Results: After the treatment, the patient's symptoms improved, but more treatments were required. Conclusion: This study can add to understanding of the effect of Korean medicine on vasovagal syncope.

• Korean Institute of Interior Design Journal
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• v.18 no.5
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• pp.119-127
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• 2009

The main goal of this research was to understand housing environment as well as the living behaviors of Korean people who reside in foreign countries. This study includes examination of dwelling units, especially focusing on dwelling behaviors by space types, arrangement and use of the space, and the according residence patterns of the Koreans in the United States. Focus group interview method and survey method were conducted; photography were taken as a visual evidence; and results were analyzed by researchers. This study strongly indicates that most of Koreans try to keep their own way of living in foreign cultures and rather readjust the housing spaces and living patterns to their own culture. The results from this study have limitations in generalizing all Korean families living in foreign cultures, because a convenience sample was used. Although studies of Korean families in Columbia, MO may not provide information that can be generalized to the entire population of Koreans overseas, we expect that this study provides useful insight in understanding and estimating the future trends in residential planning for Koreans.

• The Korean Journal of Physiology
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• v.6 no.2
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• pp.31-37
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• 1972

The right cervical vagus nerve was electrically stimulated for 30 sec, and 30 minutes recording cardiac rate responses and electrocardiogram. The main purposes of the present experiment are to determine effect of stimulation frequency on the maintenance of cardiac rate responses and to determine recovery time of sinus rhythm after asystole period followed by idioventricular rhythm during prolonged electrical stimulation of the vagus, and the optimal stimulation parameters for vagal stimulation were studied as well. The results obtained are summarized as follows: 1. The maximum negative chrontropic responses were obtained with the following ranges of electrical parameters. Intensity: 3V-7V, Frequency: 20/sec-60/sec, and pulse duration: 5 msec-20 msec. 2. Compared with the responses from sympathetic effectors, cardiac rate responses to electrical stimulation of vagus nerve were well maintained with all stimulation frequencies. 3. At all stimulation frequencies except 20/sec, sinus node started to take over primary pacemaker activity when cardiac rates were restored to about 38-40/min. 4. It was indicated that upper limit of idioventricular rhythm does not exceed 38-40/min. 5. With the stimulation parameter set of 20/sec-5 msec-3 V, sinus rhythm did not appear during 30 minutes of stimulation period. Therefore, this electrical parameter set appears to be optimal for elicitation of prolonged and maximum cardiac rate responses by vagal stimulation.

• Applied Microscopy
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• v.25 no.3
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• pp.1-19
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• 1995

The present study was performed to clarify the effect of vagus nerve stimulation on the enterochromaffin(EC) cells in the body of the stomach, the first part of the duodenum and the ceceum of rats by using routine electron microscopy and immunogold labelling. The changes in the ultrastructure and in the labelling density of the gold particles of the EC cells were investigated after vagus nerve stimulation. The vagus nerve was electrically stimulated with a square wave pulse generator for a duration of 5 minutes each, a total of 8 times at 2 minute intervals. Immunogold labelling demonstrated that the epithelial serotonin immunoreactive cells of the gastrointestinal tract are EC cells containing characteristic pleomorphic granules. Immunocytochemically labelled gold particles were largely concentrated in the dense matrix of the granules of the EC cell, and the labelling density of the gold particles considerably increased after the vagus nerve stimulation. Except for a slight activation of Golgi complexes, no remarkable changes in the ultrastructures of the EC cells were noted after the vagus nerve stimulation. The above results suggest that vagus nerve stimulation may activate serotonin biosynthesis in EC cells.