• The Korean Journal of Pharmacology
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• v.31 no.3
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• pp.291-297
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• 1995

The objectives of this study is to compare the inhibitory mechanism of sodium nitroprusside and forskolin on the phorbol ester, activator of protein kinase C (PKC), -induced contractions in rat aorta. $0.1\;{\mu}M$ phorbol dibutyrate (PDBu) induced sustained contractions and increased phosphorylations of myosin light chain (MLC) time-dependently. At 30 min, the contractions and phosphorylations of MLC by PDBu were augmented maximally and remained constant. Moreover, $^{45}Ca^{2+}$ uptake was increased 30 min after PDBu stimulation from resting values. Sodium nitroprusside which activates guanylyl cyclase followed by increasing cGMP, inhibited the PDBu-induced contractions concentration-dependently. On the other hand, forskolin which activates adenylyl cyclase followed by increasing cAMP, also inhibited the PDBu-induced contractions concentration-dependently. However, sodium nitroprusside was more potent to inhibition of the PDBu-induced contractions than forskolin. Sodium nitroprusside inhibited $^{45}Ca^{2+}$ uptake by PDBu stimulation. Forskolin also inhibited $^{45}Ca^{2+}$ uptake by PDBu stimulation. Sodium nitroprusside and forskolin inhibited the phosphorylations of MLC by PDBu, respectively. However, sodium nitroprusside was more potent to inhibition of phosphorylations of MLC by PDBu than forskolin. From these results, Sodium nitroprusside via cGMP or forskilin via cAMP may reduce myoplasmic $Ca^{2+}$ followed by suppression of phosphorylations of MLC of PKC-mediated contractions, which results in vasodilation. However, cGMP may play a role more importantly than cAMP on the regulation of protein kinase C-mediated contraction in vascular smooth muscle.

• The Korean Journal of Pharmacology
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• v.18 no.2
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• pp.79-87
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• 1982

Higenamine(dl-demethylcoclaurine, dl-1-(4-hydroxybenzyl)-6,7-dihydroxy-1,2,3,4-tetrah-ydroisoquinoline hydrochloride), which has recently been isolated from Aconite root by Drs. Kosuge and Yokota, has known to be the main cardiotonic component of the Aconite root. The present study was undertaken to investigate the effects of Higenamine on the calcium binding and release and ATPase activity of fragmented cardiac sarcoplasmic reticulum under in vitro condition. The calcium binding and release of sarcoplasmic reticulum were measured by using the double-beam spectrophotometer and the calcium sensitive dye, murexide. In the presence of $10^{-4}{\sim}5{\times}10^{-3}M$ of Higenamine, the maximal calcium binding and the initial binding rate of porcine cardiac sarcoplasmic reticulum were inhibited dose dependently by up to 43%. However, the calcium release from cardiac sarcoplasmic reticulum, which was loaded with $Ca^{++}(50{\mu}M)$, was stimulated in dose dependent manner. When incubated in the medium of 20 mM Tris-maleate(pH 7.0), 100 mM KCl, 10 mM $MgCl_2,\;0.05mM\;CaCl_2\;and\;0.014{\sim}1\;mM\;Tris-ATP\;at\;30^{\circ}C$ in the presence of Higenamine $(10^{-4}{\sim}5{\times}10^{-3}M)$, both $Ca^{++}-and\;Mg^{++}-ATPase$ of sarcoplasmic reticulum were inhibited non-competitively by Higenamine and values of $K_i$ were 4.896 mM and 6.875 mM respectively. It is suggested from the above findings that the cardiotonic effects of Higenamine might be partially explained by the inhibition of calcium binding and the stimulation of calcium release from the sarcoplasimic reticulum which may increase the free intracellular calcium that is available in the contraction of the cardiac muscle fiber.

• Journal of Biomedical Engineering Research
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• v.20 no.4
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• pp.461-469
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• 1999

In this paper, an ECG-NIBP patient monitor is designed. This is an essential equipment to measure and monitor patient's physical condition - electrocardiogram(ECG) wave, heart rate(HR), and noninvasive blood pressure(NIBP) - in ICU, CCU, and operating room. The ECG is an electrical waveform produced by relaxation and contraction of the cardiac muscle. Most physicians diagnose patient's cardiac states from ECG pattern. A blood pressure is one of the clinical indexes measured in a emergency room or operating room. In this paper, the blood pressure is measured in artery by using the nonivasive oscillometric method. The developed patient monitor was inspected and compared with other instruments in operating rooms. The results were 1bpm of maximum difference in the heart rate, 15mmHg in the systolic pressure, 16mmHg in the diastolic pressure, and 25mmHg in the mean blood pressure. But the total results were 0.15bpm of the mean difference in the heart rate, 5mmHg in the systolic pressure, 10mmHg in the diastolic pressure, and 9mmHg in the mean blood pressure. The designed ECG-NIBP patient monitor can measure the ECG wave, HR, and BP. And the multi-tasking module of pulse oximetry . respiration . temperature monitor will be added in the near future.

• YAKHAK HOEJI
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• v.38 no.2
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• pp.149-157
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• 1994

The role of nitric oxide(NO) as neurotransmitter in non-adrenergic non-cholinergic (NANC) relaxation induced by electrical stimulation has been studied in circular muscle strips of the rabbit gastric fundus. In the presence of atropine and guanethidine, low frequency$(1{\sim}20\;Hz)$ and short trains (5s) of electrical stimulation induced the frequency-dependent relaxations which were not affected by adrenergic and cholinergic blockage, but abolished by tetrodotoxin, a nerve conductance blocker. L-NNA, a stereospecific inhibitor of NO biosynthesis, inhibited the relaxations induced by electrical stimulation but not affected the relaxation to exogenous NO. The effect of L-NNA was prevented by L-arginine, the precursor of the NO biosynthesis, but not by its enantiomer, D-arginine. Exogenous administration of NO$(10{\sim}100\;{\mu}M)$ caused the concentration-dependent relaxation which showed a similarity to those obtained with electrical stimulation. Hemoglobin, a NO scavenger, abolished the NO-induced relaxations and also markedly inhibited those evoked by electrical stimulation. Application of adenosine triphosphate$(1{\sim}10\;{\mu}M)$ induced concentration-independent contractions, but in high dose caused temporary contraction followed by relaxation which was not affected by L-NNA. Exogenous vasoactive intestinal polypeptide$(10{\sim}100\;nM)$ induced the concentration-dependent relaxation, while its effects were slower in onset and more persistent than those induced by short trains and low frequencies of electrical stimulation. Based on above results, it is suggested that NO is the principal neurotransmitter of NANC nerve at relaxation induced by short trains and low frequencies of electrical stimulation in the rabbit gastric fundus.

• Biomedical Science Letters
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• v.24 no.1
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• pp.43-49
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• 2018

Electrocardiogram (ECG) is a widely used method to diagnose electrical activity of heart. Although it is a reliable and easy method, ECG could be interfered by electrical signals. One of the interfering signals is electromyogram (EMG) that is caused by muscle contraction in any parts of the body except heart. To avoid the EMG noise, an examinee is advised to be relaxed on supine position while measuring ECG. Sometimes, patients who can't put their arms and legs down on bed due to some reasons such as cast on arms or legs necessarily have the EMG noise. But detailed information about how much of the noise could be induced by positional change of arms and legs has not been reported. Here we examined the noise by analyzing ECG data from 14 candidates, 7 males and 7 females. The ECG data was obtained using the standard 12 lead ECG. EMG noise was induced by raising arms and legs at $90^{\circ}$, $60^{\circ}$ or $30^{\circ}$. Because arms are located close to the heart, noise by the raised arms was analyzed toward left or right arm separately. All of the examinees showed similar pattern of the EMG noise. EMG noise by positional change of left or right arm was clearly monitored in different limb leads. Change of leg positions induced the noise that was monitored in aVF of augmented leads and II and III of limb leads. There was a difference in degree of the noise between male and female examinees. In addition to the EMG noise, decrease of PR interval was monitored in particular positional changes, which was prominent in male examinees. These results will enlarge fundamental understanding about EMG noise in ECG.

• Journal of the Institute of Convergence Signal Processing
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• v.9 no.2
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• pp.104-111
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• 2008

The ECG is biomedical electrical signal occurring on the surface of the body due to the contraction and relaxation of the heart. This signal represents an extremely important measure for health monitoring, as it provides vital information about a patient's cardiac condition and general health. ECG signals are contaminated with high frequency noise such as power line interference, muscle artifact and low frequency nose such as motion artifact. But it is difficult to filter nose from ECG signal, and errors resulting from filtering can distort a ECG signal. The present study implemented a small-size and low-power ECG measurement system that can remove motion artifact for convenient health monitoring during daily life. The implemented ECG monitoring system consists of ECG amplifier, a low power microprocessor, bluetooth module and monitoring program. Amplifier was designed and implemented using low power instrumentation amplifier, and microprocessor was interfaced to the ECG amplifier to collect the data, process, store and feed to a transmitter. And bluetooth module used to wirelessly transmit and receive the vital sign data from the microprocessor to an PC at the receiving site. In order to evaluate the performance of the implemented system, we assessed motion artifact rejection performance in each situation with artificially set condition using adaptive filter.

• Journal of Veterinary Clinics
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• v.27 no.3
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• pp.262-267
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• 2010

Magnesium ($Mg^{2+}$) is an essential co-factor for over 325 physiological and biochemical processes so that plays a central role of neuronal activity, cardiac excitability, neuromuscular transmission, muscular contraction, vasomotor tone, and blood pressure significantly related to physical performance. However, only limited information on blood ionized $Mg^{2+}$ ($iMg^{2+}$) regarding to physical exercise is available and the data from blood total $Mg^{2+}$ detection are inconsistent. This present study investigated the changes of blood $iMg^{2+}$ correlated with metabolic demands during acute high-intensive exhaustive physical exercise in rats. After exhausted swimming (3-4 hours), blood pH, glucose, $HCO_3{^-}$, oxygen and ionized $Ca^{2+}$ ($iCa^{2+}$) were significantly decreased, whereas lactate, carbon dioxide, $iMg^{2+}$, ionized $Na^+$ and ionized $K^+$ were significantly increased. During the exhausted swimming, the changes in $iMg^{2+}$ showed a significant negative correlation with changes in pH, glucose, $HCO_3^-$ and $iCa^{2+}$, however a significant negative correlation with changes in lactate and anionic gap. It is concluded that the acute high-intensive exhaustive physical exercise could produced hypermagnesemia, an increase in blood $iMg^{2+}$ via stimulation of $iMg^{2+}$ efflux following increase in intracellular $iMg^{2+}$ from muscle induced by metabolic and respiratory acidosis.

• Korean Journal of Environmental Biology
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• v.32 no.3
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• pp.225-233
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• 2014

In this study, we investigated the changes in the physiological and histological traits of a sea squirt (Halocynthia roretzi) with the emergence of the soft tunic syndrome induced by the water temperature control (6, 9, 12, 15, 18, 21, 24 and $27^{\circ}C$). It was observed that the induction rate of the soft tunic syndrome was highest at $15^{\circ}C$, but lowest at $24^{\circ}C$. Based on the tunic color condition and contraction strength, the whole process were classified into 4 stages as S0, S1, S2 and S3. Interestingly, there were significant differences in oxygen consumption and filtration rate were observed during S0-S3. The most distinctive aspects were change of blood cell composition at stage S3, whereas multi-vacuole cell ratio was decreased by 1/2 and morula cell ratio expanded about 10 times during S0-S3. Further, change of organ structure started following the syndrome such as degeneration of epithelial cells, microfilaments, increment in hemocytes and damage in muscle fiber have been detected in tunic, siphon, branchial sac, body wall musculature and pyloric gland. Briefly, our study results indicated that the normal physiological functions of the sea squirt can be affected due to the soft tunic syndrome induced by water temperature.

• Journal of rehabilitation welfare engineering & assistive technology
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• v.11 no.3
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• pp.207-214
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• 2017

The problem of trunk stability is a major factor in back pain.. Abdominal draw in maneuver(ADIM), One of the trunk stabilization exercises to relieve lumbar instability, is a method of inducing selective contraction of the transverse abdominis associated with anticipatory posture control among the abdominal stabilization muscles. ADIM is usually performed with a visual feedback by applying a pressure biofeedback unit(PBU) under the lumbar at the supine position, which is not functional compared to the sitting position. This study was conducted to investigate the effect of ADIM applied in supine and sitting position on 31 healthy men and women. In each posture, muscle activity was measured by rectal abdominis (RA), external oblique (EO), transverse abdominis (TrA)/internal obilique (IO) and erector spinae (ES) using wireless EMG. In the result, there was no significant difference between RA and EO between the two postures and there was a significant difference between TrA / IO and ES. In both postures, the activity of TrA/IO was higher than that of RA, and the effect of ADIM was shown to be the same, whereas TrA/IO and ES showed higher activity in sitting position. This means that the activity of the muscles involved in the postural stability and lumbar stability is increased further in the sitting position. Therefore, ADIM in sitting, which can be applied more easily in daily life, is useful for improving lumbar stability.

• Korean Journal of Environment and Ecology
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• v.29 no.6
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• pp.858-864
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• 2015

Developmental changes in the vocal signals of serotine bats (Eptesicus serotinus) during their infancy were examined in this study. The analysis was conducted on 4 infant serotine bats from 1 to 40 days after their birth. Pulse duration (PD), pulse interval (PI), peak frequency (PF), maximum frequency ($F_{MAX}$), minimum frequency ($F_{MIN}$), and bandwidth (BW) were measured. As the bats grew, their vocalizations became increasingly consistent and similar to those of adults. For infant bats, PD and PI decreased as they grew older, whereas PF, $F_{MAX}$, $F_{MIN}$, and BW increased. The greatest change in vocalizations was observed between the $10^{th}$ and $20^{th}$ days after birth. Also, PF, $F_{MAX}$, $F_{MIN}$ and BW, which describe sound frequency, increased dramatically during the period between the $10^{th}$ and the $20^{th}$ days. In contrast, the greatest change in PD occurred between the $30^{th}$ and $40^{th}$ days after birth. The results collected in this study suggest that frequency increased as the contraction ability of the muscles developed by around 20 days of age. Muscle relaxation ability, which is related to PD, was found to develop significantly at 30 to 40 days of age. According to the results of this study, although 40 day-old infant bats are not yet able to fly, their vocal signals were similar to those of adults. This indicates that vocal development and flying activity develop separately in young bats.