• Title/Summary/Keyword: Current Stimulation

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CORRELATIONS BETWEEN HIPPOCAMPAL THETA RHYTHM AND INTRACELLULAR CHARACTERISTICS OF PYRAMIDAL NEURONS (해마 theta 리듬과 pyramidal neuron의 세포내 특성과의 상관관계)

  • Kwon, Oh-Heung;Kim, Young-Jin;Nam, Soon-Hyeun;Kim, Hyeun-Jung;Lee, Man-Gee;Cho, Jin-Hwa;Choi, Byung-Ju
    • Journal of the korean academy of Pediatric Dentistry
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    • v.25 no.4
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    • pp.671-682
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    • 1998
  • Electrophysiological phenomena of pyramidal cells in the CA1 area of the dorsal hippocampus were recorded from and filled with neurobiotin in anesthetized rats. The electropharmacological properties of membrane as well as the cellular-synaptic generation of rhythmic slow activity (theta) were examined. The intracellular response characteristics of these pyramidal cells were distinctly different from responses of interneurons. Pyramidal cells had a high resting membrane potential, a low input resistance, and a large amplitude action potential. A afterhyperpolarization was followed a single action potential. Most of pyramidal cells did not display a spontaneous firing. Pyramidal cells displayed weak inward rectification and anodal break excitation. The slope of the frequency-current relation was 53.4 Hz/nA for the first interspike interval and 15.9 Hz/nA for the last intervals, suggesting the presence of spike frequency adaptation. Neurobiotin-filled neurons showed pyramidal morphology. Cells were generally bipolar dendritc processes ramifying in stratum lacunosum-moleculare, radiatum, and oriens. Commissural stimulation discharged pyramidal cells, followed by excitatory and inhibitory postsynaptic potentials (EPSPs and IPSPs). The frequency of theta-related membrane potential oscillation was voltage-independent in pyramidal neurons. At strong depolarization levels (less than 30 mV) pyramidal cells emitted sodium spike oscillation, phase-locked to theta. The observations provide direct evidence that theta-related rhythmic hyperpolarization of principal cells is brought by the rhythmically discharging interneurons. Furthermore, the findings in which interneurons were also paced by rhythmic inhibitory postsynaptic potentials during theta suggest that they were periodically hyperpolarized by their GABAergic septal afferents.

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The role background noise intensity on Physiological activity during performance of mental task (인지과제 수행시 배경 소음의 크기에 따른 생리적 반응차)

  • Sohn Jin-Hun;Sokhadze Estate M.;Min Yoon-Ki;Lee Kyung-Hwa;Choi Sangsup
    • Proceedings of the Acoustical Society of Korea Conference
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    • spring
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    • pp.269-273
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    • 1999
  • Combination of mental stress task with noise background is a traditional tool employed in psychophysiology. However, intensity of background noise is a factor affecting both performance on test and psychophysiological responses associated with stress evoked by mental load in noisy environment. In the current study on 7 subjects we analyzed the influence of white noise (WN) intensity (55, 70, and 85 dB[A] ) on psychophysiological responses during word recognition test performed on noise background. There were recorded following physiological variables: electrodermal activity (EDA) , namely, skin conductance level (SCL), skin conductance response (SCR) amplitude (SCR-A), rise time and total number of SCRs (N-SCR); cardiovascular activity, e.g., heart rate (HR), respiratory sinus arrhythmia (RSA) index, pulse transit time (PTT), finger pulse volume (PV), skin temperature (SKT) and respiratory activity, such as respiration rate (RESP-R) and inspiration wane amplitude (RESP-A) during baseline resting state and 40 s long performance on 3 similar Korean word recognition tests with different WN intensity (55, 70, and 85 dB). Electrodermal responses (SCR-A, SCL, N-SCR) demonstrated gradual increment with increased intensity of noise, and this increase of response magnitude with higher intensity of noise was typical also for r skin temperature (phasic SKT decrease) and pulse volume (phasic and tonic PV decrease). However, some cardiovascular and respiratory responses did not exhibit same tendency of gradual increase of reactivity , namely HR, as well as RESP-R and RESP-A showed decrement of response magnitudes. Important finding in terms of cardiovascular reactivity was that 55 and 70dB evoked similar profiles, while 85dB WN resulted in significantly different profile of reactions, suggesting that there exists a threshold level after which intensive auditory stimulation elicits psychophyslological responses pattern of different quality. There are discussed potential autonomic mechanism involved in mediation of observed physiological responses.

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Effect of Sopung-tang and tDCS on Motor function Recovery and GDNF Expression in Photothrombotic Brain Infarction Induced Rat Model (광혈전 유도 뇌손상 백서에서 소풍탕(疏風湯)과 tDCS의 적용이 운동기능회복과 GDNF 발현에 미치는 영향)

  • Sim, Ki Cheol;Kim, Gi Do;Kim, Kyung Yoon;Chung, Hun Woo;Kim, Gye Yeop
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.26 no.6
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    • pp.894-901
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    • 2012
  • The effect of Sopung-tang(SPT) and trans-cranial direct current stimulation(tDCS) was investigated in photothrombotic brain infarction(PTI) rats. Sprague-Dawley 80 rats, were divided into four groups. group I was experiental control group(n=20), group II was PTI induced and oral administration of SPT(n=20), group III was PTI induced and tDCS administration(n=20) and group IV was PTI induced and SPT and tDCS administration for 28 days on stroke rats(n=20). Analysis the neurological function test, 25 point behavior functional score test, and immunohistochemistric finding of GDNF expression, and electron microscopy assessment In motor behavior test, the outcome of group IV was significantly difference than the other group, and In immunohistochemistric finding, group II, III, IV were increase GDNF expression on 28 days, In electron microscopy finding, the all groups were degenerated of cell organelles, and synaptic plasticity were improvement of group II, III, IV(especially group IV) These results suggest that, 28days application of SPT and tDCS was the motor function and histopathologic, micro-morphological improvement of motor function recovery and positive influence on synaptic plasticity.

A STUDY ON THE EFFECT OF ELECTRO-ACUPUNCTURE ON ORAL PAIN (전기침이 구강동통에 미치는 영향에 관한 연구)

  • Choi, Yong-Sung;Lee, Chang-Seop;Song, Hyeong-Geun;Lee, Sang-Ho
    • Journal of the korean academy of Pediatric Dentistry
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    • v.23 no.3
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    • pp.717-728
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    • 1996
  • The effects of electro-acupuncture on the pain threshold and the amplitude of dEMG(di-gastric EMG) evoked by the noxious electric stimulation on teeth and gingiva in dogs were studied. Experiments were carried out with 10 dogs weighing 5-8kg. Each animal was anestheticed with Entobar given intraperitoneally in an initial dose of 30mg/kg. Maintenance dose of 5mg/kg/hr was given through a cannula, in the femoral vein, as required to keep up light anesthesia. Bipolar stimulating wire electrodes, 0.1mm in diameter, insulated except for tips, were inserted into the upper canine and palatal gingiva. Rectangular aluminium plate electrodes (15$\times$5mm) were placed on acupuncture points, called Yin-Hsiang, located at both sides of the upper jaw. Rectangular biphasic current pulses of 2Hz, with a $250{\mu}sec$ duration, were delivered for 15 minutes. The dEMG activities were recorded from the anterior belly of the digastric muscle(one of the jaw opening muscles) using bipolar wire electrodes. The magnitude of the jaw opening reflex at different intensties of electro-acupuncture(1volt 4volt and 10volt) was estimated by averaging the 30 superimposed dEMGs recorded on an oscilloscope and audiomonitor. Data were analysed statistically with ANOV A and paired t-test. The obtained results were as follows: 1. Pain thresholds were increased 7.7 %, 15.4 %, 17.3 % in the teeth and 11.1 %, 19.0 %, 25.4 % in the gingiva as the intensities of electro-acupuncture increased incrementally. 2. Amplitudes of dEMG were decreaed 8.3%, 22.4%, 27.4% in the teeth and 9.8%, 36.5%, 42.2 % in the gingiva as the intensities of electro-acupuncture increased incrementally. 3. Inhibition of pain responses by the electroacupuncture was more effective in the gingiva than in the teeth.

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Molecular cloning and characterization of novel human JNK2 (MAPK9) transcript variants that show different stimulation activities on AP-1

  • Wang, Pingzhang;Xiong, Ying;Ma, Chuan;Shi, Taiping;Ma, Dalong
    • BMB Reports
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    • v.43 no.11
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    • pp.738-743
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    • 2010
  • The c-Jun $NH_2$-terminal kinase (JNK) signaling pathway participates in many physiological functions. In the current study we reported the cloning and characterization of five novel JNK2 transcript variants, which were designated as $JNK2\alpha3$, $JNK2\alpha4$, $JNK2\beta3$, $JNK2\gamma1$ and $JNK2\gamma2$, respectively. Among them, $JNK2\alpha4$ and $JNK2\gamma2$ are potential non-coding RNA because they contain pre-mature stop codons. Both $JNK2\alpha3$ and $JNK2\beta3$ contain an intact kinase domain, and both encode a protein product of 46 kDa, the same as those of $JNK2\alpha1$ and $JNK2\beta1$. $JNK2\gamma1$ contains a disrupted kinase domain and it showed a disable function. When over-expressed in mammalian cells, $JNK2\alpha3$ showed higher activity on AP-1 than that of $JNK2\beta3$ and $JNK2\gamma1$. Furthermore, $JNK2\alpha3$ and $JNK2\beta3$ showed different levels of substrate phosphorylation, although they both could promote the proliferation of 293T cells. Our results further demonstrate that JNK2 isoforms preferentially target different substrates and may regulate the expression of various target genes.

Novel Enhanced Flexibility of ZnO Nanowires Based Nanogenerators Using Transparent Flexible Top Electrode

  • Gang, Mul-Gyeol;Ha, In-Ho;Kim, Seong-Hyeon;Jo, Jin-U;Ju, Byeong-Gwon;Lee, Cheol-Seung
    • Proceedings of the Korean Vacuum Society Conference
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    • 2014.02a
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    • pp.490.1-490.1
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    • 2014
  • The ZnO nanowire (NW)-based nanogenerators (NGs) can have rectifying current and potential generated by the coupled piezoelectric and semiconducting properties of ZnO by variety of external stimulation such as pushing, bending and stretching. So, ZnO NGs needed to enhance durability for stable properties of NGs. The durability of the metal electrodes used in the typical ZnO nanogenerators(NGs) is unstable for both electrical and mechanical stability. Indium tin oxide (ITO) is used as transparent flexible electrode but because of high cost and limited supply of indium, the fragility and lack of flexibility of ITO layers, alternatives are being sought. It is expected that carbon nanotube and Ag nanowire conductive coatings could be a prospective replacement. In this work, we demonstrated transparent flexible ZnO NGs by using CNT/Ag nanowire hybrid electrode, in which electrical and mechanical stability of top electrode has been improved. We grew vertical type ZnO NW by hydrothermal method and ZnO NW was coated with hybrid silicone coating solution as capping layer to enhance adhesion and durability of ZNW. We coated the CNT/Ag nanowire hybrid electrode by using bar coating system on a capping layer. Power generation of the ZnO NG is measured by using a picoammeter, a oscilloscope and confirmed surface condition with FE-SEM. As a results, the NGs using the CNT/Ag NW hybrid electrode show 75% transparency at wavelength 550 nm and small change of the resistance of the electrode after bending test. It will be discussed the effect of the improved flexibility of top electrode on power generation enhancement of ZnO NGs.

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A comparative study of effects using physical treatmental apparatus and diagnosis of shoulder pain on cerebrovascular attack patients (뇌졸중환자중(腦卒中患者中) 견관절동통(肩關節疼痛)에 관(關)한 진단(診斷) 및 치료기기효과(治療器機效果)에 대(對)한 비교(比較) 연구(硏究))

  • Kang, Jae-Chun;Baik, Tai-Hyun
    • The Journal of Internal Korean Medicine
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    • v.20 no.1
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    • pp.244-260
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    • 1999
  • This study was to investigate diagnosis of shoulder pain on cerebrovascular attack patients and treatment effects by using physical treatment and orienatal diagnosis aparatus, as oriental diagnosis equipments, these were used thermography, maegzin and yangdorag machine. as physical treatment equipments, these were used Hot pack, TENS (Transcutaneous electrical nerve stimulation), ICT(Interferential current therapy) the results were followed 1. In Sex and Age distribution on cerebrovascular attack patients with shoulder pain, male(51.7%)had many than female(48.3%) and 60s were the top, next 70s 50s 40s. 2. In the reason of cerebrovascular attack and the type of motor paresis, cerebrovascular infarction(73.3%) had many than hemorrhage(26.7%) 3. In hospitalizied period of cerebrovascular attack patients with shoulder pain, the period from 11 to 60 days had almost occupied. 4. Oriental medical diagnositic propriety of shoulder pain by using maegzin and yangdorag machine were not recognized. 5. In measuring passive range of motion of pre and post treatment, improvement effect on Hot pack was not showed, but effects on TENS, ICT were showed. 6. In measuring temperature of painful shouler joint of pre and post treatment by using thermography, the effect of Hot pack was not recognized but the effects of TENS, ICT were recognized.

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A comprehensive review of the comparative studies of Korean(Panax ginseng) and American(Panax quinquefolium) Ginsengs on the Thermogenic Response (고려인삼(Panax ginseng)과 미국삼(Panax quinquefolium)의 승열작용에 대한 비교 고찰)

  • Nam, Ki Yeul;Yang, Byung Wook;Shin, Wang Soo;Park, Jong Dae
    • Korean Journal of Pharmacognosy
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    • v.49 no.3
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    • pp.203-218
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    • 2018
  • It has been extensively known in the high temperature regions such as southern China and south east Asia that Korean ginseng(Panax ginseng) intake raises body heat, while American ginseng(Panax quinquefolium) lowers it, based upon oriental medicine. This is likely due to the misunderstanding of the conception that Korean ginseng shows a warm property, resulting in enhanced blood circulation and stimulation of metabolism. It's further supported by the fact that current scientific studies have shown no notable side effects. Moreover, it has been demonstrated in animal experimental test that Korean ginseng shows a complementary effect in a high temperature environment, together with scientific evidence of a preventive effect of ginseng saponin against cold conditions, suggesting it to exhibit an adaptogenic effect normalizing the body under abnormal body conditions. However, there is a shortage of studies published concerning comparative clinical and animal studies of Korean and American ginsengs, and also, on natives of high temperature countries. Therefore, a further placebo-controlled clinical study has to be considered to elucidate scientifically clinical evaluation of Korean and American ginsengs on the body heat. In this article, we summarize the scientific publications reporting the clinical comparative study of Korean and American ginsengs on body heat response.

LORETA analysis of EEG responding to positive/negative emotional stimuli for different sensitivities of behavioral activation and inhibition systems (긍/부정 감성자극에 대한 행동활성화체계 및 행동억제체계 민감도에 따른 뇌파의 LORETA 분석)

  • Kim Wuon-Shik;Jin Seung-Hyun
    • Science of Emotion and Sensibility
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    • v.8 no.4
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    • pp.403-413
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    • 2005
  • The purpose of the present study was to investigate the responses to positive/negative emotional stimuli for the different sensitivities of behavioral activation system (BAS) and behavioral inhibition system (BIS). We recorded If-channel EEG data for 8 BAS sensitive subjects an48 BIS sensitive subjects. EEGs were analyzed with LORETA (Low-resolution electromagnetic tomography) From scalp-recorded electrical potential distribution, LORETA computes the three-dimensional intracerebral distributions of current density for specified EEG frequency bands. hs results , significant differences between the BAS sensitive group ant the BIS sensitive group appeared LORETA alpha activities over the prefrontal lobe and the cingulate gyrus. Prefrontal regions and limbic system including cingulate gyrus are involved in emotional processing. Moreover, subjects with the high BAS sensitivity. responded more sensitively to the positive stimulation than subjects with the high BIS sensitivity. Therefore, our results suggest the possibility of correlation between BAS/BIS sensitivity and positive/negative emotional stimuli.

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Effects of Dopamine on the Contractility and Action Potential of the Rabbit Papillary Muscle (Dopamine이 토끼 유두근의 수축력과 활동전압에 미치는 영향)

  • Huh, In-Hoi;Park, Jong-Wan
    • YAKHAK HOEJI
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    • v.32 no.6
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    • pp.402-414
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    • 1988
  • In order to clarify the receptor types and mechanisms underlying the positive inotropic effect of dopamine on the mammalian ventricular myocardium, the action potential, its first derivatives and isometric contraction of the rabbit papillary muscle were recorded using a force transducer and glass capillary microelectrodes filled with 3M KCl. The results were as follows; (1) In normal Tyrode solution, the contractile force was increased and duration of action potential was shortened with increments of dopamine concentration ($10^{-6}-10^{-4}M$). (2) The dose-response curve was markedly shifted to the right by pretreatment with reserpine (5mg/kg i.p., 24hrs prior to the experiment). (3) In 19mM $K^+-Tyrode$ solution, the duration of action potential, maximum rate of rise (V_{max}) of action potential and overshoot were significantly increased with increments of dopamine concentration ($10^{-6}-10^{-4}M$). (4) The inotropic effect of dopamine on the rabbit papillary muscle pretreated with reserpine was antagonized by atenolol ($10^{-6}M$), but not by phentolamine ($3{\times}10^{-6}M$). (5) In rabbit papillary muscle partially depolarized by 19mM $K^+-Tyrode$ solution, slow electrical response (calcium mediated action potential) as well as contraction were restored by dopamine ($10^{-4}M$); this restoration was blocked by calcium antagonists ($3{\times}10^{-5}M$ $LaCl_3{\cdot}6H_2O$, $3{\times}10^{-6}M$ diltiazem) or ${\beta}-adrenoceptor$ antagonist ($3{\times}10^{-6}M$ atenolol), but not affected by ${\alpha}-adrenoceptor$ antagonist ($10^{-5}M$ phentolamine, $3{\times}10^{-6}M$ yohimbine) or vascular dopaminergic receptor antagonist ($10^{-5}M$ haloperidol). The above results may be interpreted as that the positive inotropic effect of dopamine through both direct and indirect action are caused by increase in slow inward current ($Ca^{2+}$ influx into themyocardial cell), and the direct action is mainly due to the stimulation of ${\beta}-adrenoceptors$ in the rabbit papillary muscle.

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