• Title/Summary/Keyword: stimulator

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Increase of L-type Calcium Current by cGMP-dependent Protein Kinase Regulates in Rabbit Ventricular Myocytes

  • Han, Jin;Kim, Na-Ri;Kim, Eui-Yong;Ho, Won-Kyung;Earm, Yung-E;Kim, Han-Kyoun
    • The Korean Journal of Physiology and Pharmacology
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    • v.2 no.6
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    • pp.733-742
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    • 1998
  • Background: We have previously reported that not only cGMP but also 8-Br-cGMP or 8-pCPT-cGMP, specific and potent stimulators of cGMP-dependent protein kinase (cGMP-PK), increased basal L-type calcium current $(I_{Ca})$ in rabbit ventricular myocytes. Our findings in rabbit ventricular myocytes were entirely different from the earlier findings in different species, suggesting that the activation of cGMP-PK is involved in the facilitation of $I_{Ca}}$ by cGMP. However, there is no direct evidence that cGMP-PK can stimulate $I_{Ca}}$ in rabbit ventricular myocytes. In this report, we focused on the direct effect of cGMP-PK on $I_{Ca}}$ in rabbit ventricular myocytes. Methods and Results: We isolated single ventricular myocytes of rabbit hearts by using enzymatic dissociation. Regulation of $I_{Ca}}$ by cGMP-PK was investigated in rabbit ventricular myocytes using whole-cell voltage clamp method. $I_{Ca}}$ was elicited by a depolarizing pulse to +10 mV from a holding potential of -40 mV. Extracellular 8-(4-Chlorophenylthio)-guanosine-3',5'-cyclic monophosphate (8-pCPT-cGMP), potent stimulator of cGMP-dependent protein kinase (cGMP-PK), increased basal $I_{Ca}}$. cGMP-PK also increased basal $I_{Ca}}$. The stimulation of basal $I_{Ca}}$ by cGMP-PK required both 8-Br-cGMP in low concentration and intracellular ATP to be present. The stimulation of basal $I_{Ca}}$ by cGMP-PK was blocked by heat inactivation of the cGMP-PK and by bath application of 8-(4-chlorophenylthio)-guanosine-3',5'-cyclic monophosphate, Rp-isomer (Rp-pCPT-cGMP), a phosphodiesterase-resistant cGMP-PK inhibitor. When $I_{Ca}}$ was increased by internal application of cGMP-PK, IBMX resulted in an additional stimulation of $I_{Ca}}$. In the presence of cGMP-PK, already increased $I_{Ca}}$ was potentiated by bath application of isoprenaline or forskolin or intracellular application of cAMP. Conclusions: We present evidence that cGMP-PK stimulated basal $I_{Ca}}$ by a direct phosphorylation of L-type calcium channel or associated regulatory protein in rabbit ventricular myocytes.

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Effects of Administration of Pyritum on Fracture Healing in Mice (자연동(自然銅)이 초기 골절 생쥐 정강이뼈의 Re-modeling에 미치는 영향)

  • Shin, Kyung-Min;Jung, Chan-Yung;Hwang, Min-Seop;Lee, Seung-Deok;Kim, Kyung-Ho;Kim, Kap-Sung
    • Journal of Acupuncture Research
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    • v.26 no.5
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    • pp.65-75
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    • 2009
  • Objectives : Pyrite is one of the important prescriptions that has been used in oriental medicine for healing of fracture. It is reasonable, therefore, to postulate that native copper affects the process of bone metabolism and bone formation. The purpose of this study is to discover the effect of Pyrite on the healing of tibia fracture. Methods : 1. In vitro test : MG-63 cell in human body and the Pyritum in the ratio of 0.5mg/ml, 1.0mg/ml, 1.5mg/ml, 2.0mg/ml were incubated for 24 hours. After 24 hours, RNA was extracted via trizol reagent (Sigma, USA). In order to understand the activation of osteoblast, the level of OPN mRNA, osteopontin, was measured. 2. In vivo tesgroups normal group, control group and experimental group. Left tibia bones of mice in CON and JT groups were fractured by bone cutters. Pyrite was orally administered to the experimental group. After 14 days, each group's tibia specimen was constructed to observe changes in activation of proinflmmatory cytokines in relation to MIF and IL-6. Also, proliferation of osteoblast and osteopontin were measured via changes in levels of OPN and OPN mRNA. Results : In jn-Titro test, the level of OPN mRNA, osteopontin production was remarkably increased in Pyritum-treated MG-63 cells. In in-vitro test, fractured area in external tibia morphology was increased more in the JT group than that of the CON group. Osteogenesis, endochodrial ossification, and osteoid in fractured area were also increased more in the JT group than that of the CON group. Increase in OPN mRNA, osteopontin level and osteoblast's proliferation were observed. Activation of MIF and IL-6 was confirmed from the fracture region. Conclusions : From the result, development of a new stimulator in healing fracture via pyrite is expected.

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Effect of rTMS on Motor Sequence Learning and Brain Activation : A Preliminary Study (반복적 경두부 자기자극이 운동학습과 뇌 운동영역 활성화에 미치는 영향 : 예비연구)

  • Park, Ji-Won;Kim, Jong-Man;Kim, Yun-Hee
    • Physical Therapy Korea
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    • v.10 no.3
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    • pp.17-27
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    • 2003
  • Repetitive transcranial magnetic stimulation (rTMS) modulates cortical excitability beyond the duration of the rTMS trains themselves. Depending on rTMS parameters, a lasting inhibition or facilitation of cortical excitability can be induced. Therefore, rTMS of high or low frequency over motor cortex may change certain aspects of motor learning performance and cortical activation. This study investigated the effect of high and low frequency subthreshold rTMS applied to the motor cortex on motor learning of sequential finger movements and brain activation using functional MRI (fMRI). Three healthy right-handed subjects (mean age 23.3) were enrolled. All subjects were trained with sequences of seven-digit rapid sequential finger movements, 30 minutes per day for 5 consecutive days using their left hand. 10 Hz (high frequency) and 1 Hz (low frequency) trains of rTMS with 80% of resting motor threshold and sham stimulation were applied for each subject during the period of motor learning. rTMS was delivered on the scalp over the right primary motor cortex using a figure-eight shaped coil and a Rapid(R) stimulator with two Booster Modules (Magstim Co. Ltd, UK). Functional MRI (fMRI) was performed on a 3T ISOL Forte scanner before and after training in all subjects (35 slices per one brain volume TR/TE = 3000/30 ms, Flip angle $60^{\circ}$, FOV 220 mm, $64{\times}64$ matrix, slice thickness 4 mm). Response time (RT) and target scores (TS) of sequential finger movements were monitored during the training period and fMRl scanning. All subjects showed decreased RT and increased TS which reflecting learning effects over the training session. The subject who received high frequency rTMS showed better performance in TS and RT than those of the subjects with low frequency or sham stimulation of rTMS. In fMRI, the subject who received high frequency rTMS showed increased activation of primary motor cortex, premotor, and medial cerebellar areas after the motor sequence learning after the training, but the subject with low frequency rTMS showed decreased activation in above areas. High frequency subthreshold rTMS on the motor cortex may facilitate the excitability of motor cortex and improve the performance of motor sequence learning in normal subject.

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Synergic Anti-Pruritic and Anti-Inflammatory Effects of Scutellariae Radix plus Flos Loncerae Extracts in Rat Peritoneal Mast Cell and Chemical Antigen-Induced Mice (렛트 복강 비만세포와 화학항원 유도 알레르기 마우스에서 황금과 금은화 추출물의 항가려움 및 항염증 상승효과)

  • Mok, Ji Ye;Jeon, In Hwa;Kim, Hyeon Soo;Shin, Jun Ho;Park, Yong Gyoun;Jang, Seon Il
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.27 no.1
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    • pp.83-91
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    • 2013
  • Pruritus is a unpleasant symptom in the skin that provokes the act of or desire to scratch. Mast cells are important effector cells in allergic reactions such as pruritus and inflammation. The purpose of this study was undertaken to investigate the synergic anti-pruritic and anti-inflammatory effects of Scutellariae Radix (SB) plus Flos Loncerae (FL) extracts in rat peritoneal mast cells (RPMCs), pruritogen-induced scratching mice and 2,4-dinitrofluorobenzene (DNFB)-induced allergic mice. We investigated the effect of SB, FL and SB plus FL extracts on the production of tumor necrosis factor (TNF)-${\alpha}$, interleukin (IL)-$1{\beta}$, and histamine in RPMCs, on the scratching behavior in ICR mice, and skin clinical serverity and inflammatory mediators in DNFB-induced allergic hairless mice. RPMCs stimulated with PMA plus A23187 or compound 48/80 significantly increased TNF-${\alpha}$, IL-$1{\beta}$ or histamine production compared with media control. However, TNF-${\alpha}$ IL-$1{\beta}$ or histamine levels increased by PMA plus A23187 or compound 48/80 treatment were significantly inhibited by SB, FL in a dose-dependent manner. Especially, SB plus FL pretreatment had a synergic inhibitory effects on stimulator-induced cytokines (TNF-${\alpha}$ and IL-$1{\beta}$) and histamine production. Moreover, SB plus FL administration had a synergic inhibitory effects on the scratching behavior induced by pruritogen (compound 48/80, histamine, serotonin, substance P) in ICR mice. Furthermore, SB plus FL administration had a synergic inhibitory effects on skin damage, inflammatory mediators, leukocyte and mast cell infiltration induced by DNFB in hairless mice. These results suggest that SB plus FL administration has a potential use as a medicinal plant for treatment against itching and inflammation-related skin disease.

Active Component of Fatsia japonica Enhances the Transduction Efficiency of Tat-SOD Fusion Protein both In Vitro and In Vivo

  • Lee, Sun-Hwa;Kim, So-Young;Kim, Dae-Won;Jang, Sang-Ho;Lim, Soon-Sung;Kwon, Hyung-Joo;Kang, Tae-Cheon;Won, Moo-Ho;Kang, Il-Jun;Lee, Kil-Soo;Park, Jin-Seu;Eum, Won-Sik;Choi, Soo-Young
    • Journal of Microbiology and Biotechnology
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    • v.18 no.9
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    • pp.1613-1619
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    • 2008
  • It has been reported that Tat-SOD can be directly transduced into mammalian cells and skin and acts as a potential therapeutic protein in various diseases. To isolate the compound that can enhance the transduction efficiency of Tat-SOD, we screened a number of natural products. 3-O-[$\beta$-D-Glucopyranosyl(1$\rightarrow$4)-$\alpha$-L-arabinopyranosyll-hederagenin (OGAH) was identified as an active component of Fatsia japonica and is known as triterpenoid glycosides (hederagenin saponins). OGAH enhanced the transduction efficiencies of Tat-SOD into HeLa cells and mice skin. The enzymatic activities in the presence of OGAH were markedly increased in vitro and in vivo when compared with the controls. Although the mechanism is not fully understood, we suggest that OGAH, the active component of Fatsia japonica, might change the conformation of the membrane structure and it may be useful as an ingredient in anti-aging cosmetics or as a stimulator of therapeutic proteins that can be used in various disorders related to reactive oxygen species (ROS).

Studies on the Cumulus Expansion and Oocyte Maturation of Mouse Cumulus-Oocyte Complexes: Regulation of Intracellular cAMP Level (생쥐 난자-난구 복합체의 성숙과 분산에 관한 연구 : 세포내 cAMP의 조절)

  • 권혁방;고선근;임욱빈
    • The Korean Journal of Zoology
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    • v.30 no.1
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    • pp.1-9
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    • 1987
  • Cyclic AMP (cAMP) was known to play a key role in the regulation of cumulus expansion and oocyte maturation of mammalian cumulus-oocyte complexes (COC's) in vivo and in vitro. The present experiments were conducted to know how intracellular level of cAMP in these cells is controlled. Intracellular cAMP level was modulated by culturing mouse CGC's with an adenylate cyclase stimulator, forskolin, a phosphodiesterase inhibitor, 3-isobutyl-1-methyixanthine (IBMX), human chorionic gonadotrophin (HCG), or follicle stimulating hormone (FSH). The rate of cumulus expansion and germinal vesicle break-down (GVBD) was checked after culture and used as a biological end point. Forskolin in the medium began to stimulate the expansion of the complexes at 1 nM and induced maximum expansion (80~90%) at 0 1~10 $\mu$M. The expansion rate was reduced to 60% when forskolin concentration was increased to 100 $\mu$M. Oocyte GVBD occurred normally (75~82%) in the presence of 10 $\mu$M of forskolin, but partial suppression was appeared at 100 pM of the drug (40%). IBMX also stimulated the expansion from the concentration of 0.01 pM and induced full expansion (81~89%) between the concentration of 1-1000 $\mu$M. Meiotic resumption was occurred normally under 10 $\mu$M of IBMX, but suppressed drastically from the concentration of 100 $\mu$M. The minimum exposing time to hormone or drugs required to trigger cumulus expansion was two minutes with HCG, 15~30 minutes with FSH and fors kolin, and two hours with IBMX. The data presented here seemed to imply that intracellular cAMP level in cumulus cells is regulated by both adenylate cyclase and phosphodiesterase and cumulus expansion is induced by a peak of cAMP while meiotic arrest is maintained by continuous presence of cAMP.

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Research on the usage of oral hygiene devices and the general knowledge, attitude on oral health care in the orthodontic patients (교정환자의 구강건강관리에 관한 지식도와 태도 및 구강위생용품 사용실태)

  • Min, Hee-Hong;Na, Eun-Joo;Jun, Ji-Hean;Park, Young-Nam
    • Journal of Korean society of Dental Hygiene
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    • v.12 no.2
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    • pp.399-407
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    • 2012
  • Objectives : Purpose of this research is to determined the general knowledge on oral health and the usage of oral hygiene products in the orthodontic patients and try to provide an appropriate oral hygiene products for the patients. Methods : Orthodontic patients who visited a dental clinic in Daejeon were selected and data from 352 patients were collected. Questionnaire based on survey was conducted from 1st of March to 30th in 2011 and all the data was analysed by using SPSS statistical program (VER 15.0). Frequency analysis, $x^2$ test, T-test and the amount of diurnal variance analysis (one-way ANOVA) were also used. After that, scheffe's post-test method was conducted. Results : According to the general characteristics of oral health care knowledge score was $2.87{\pm}0.60$, the attitude score was $2.96{\pm}0.57$. toothbrush replacement cycle were less than 3 months (p=0.007, p=0.000) and frequency of brushing one day more than three times higher in patients with knowledge to help attitude. according to the sex, age, and duration of orthodontic treatment with oral hygiene devices of usage was higher in the calibration toothbrush usage, awareness was higher in the interdental toothbrushes. according to the type of orthodontic devices from the oral hygiene devices usage, removable group was the orthodontic toothbrush and electric toothbrush group were highest in the 'unknown', the fixed group was orthodontic toothbrush(67.3%) and electric toothbrushes(40.8%) was higher in the usage. Patients who used oral hygiene devices such as orthodontic tooth brush, interdental brush, electric toothbrush, water pik and fern solution showed wider knowledge on oral health care and oral hygiene devices compared to patients who answered as does not aware of oral hygiene devices and never used these products before. Conclusions : Orthodontic patient's oral health attitudes, knowledge, and oral hygiene devices usage are the general characteristics of the highest in the orthodontic toothbrush usage, awareness was higher in the interdental brush. Water pik and fern solution, rubber and gingival interdental stimulator turned massage does not use or low. Based on results from research, overall orthodontic patients who visited a dental clinic had low awareness and usage of oral hygiene devices. Therefore, it is required to educate general publics and the orthodontic patients and also promote the importance of usage of oral hygiene devices.

Characterization of Phytase from Bacillus coagulans IDCC 1201 (Bacillus coagulans IDCC 1201이 생산하는 Phytase의 특성)

  • Lee Seung-Hun;Kwon Hyuk-Sang;Koo Kyo-Tan;Kang Byung-Hwa;Kim Tae-Yong
    • Microbiology and Biotechnology Letters
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    • v.34 no.1
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    • pp.28-34
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    • 2006
  • A native extracellular acid phosphatase, phytase (EC 3.1.3.8), from Bacillus coagulans IDCC 1201 (commercially known as Lactobacillus sporogenes) used as probiotics, was characterized. Though some strains of B. coagulans have been evaluated with regard to several health-promoting effects, it has not been reported to produce phytase. Partially purified phytase front the strain IDCC 1201 had a pH optimum of 4.0 and a temperature optimum of $50^{\circ}C$, respectively. The requirement for divalent cations was studied and cobalt ion remarkably increased the enzyme activity. The removal of metal ions from the enzyme by EDTA decreased activity below 50%. The enzyme activity depleted restored when the assay was performed in the presence of $Co^{2+}$. Also, $Co^{2+}$ is the most active stimulator and has unique activation effect at high temperature. The phytase was specific for sodium phytate and p-nitrophenylphosphate, which is different from other known Bacilli phytases. The putative amino acid sequences of the phytase from B. coagulans IDCC 1201 were very similar to that of the phytase from B. subtilis strain 168. Based on these data, we concluded that the phytase from B. coagulans IDCC 1201 is a $Co^{2+}$-dependent acid phosphatase. Therefore, the strain B. coagulans IDCC 1201 is thought to be a valuable addititive for livestocks as well as a beneficial probiotics for human.

The Analgesic Effects of Transcutaneous Electrical Nerve Stimulation and Interferential Currents on the Experimental Ischemic Pain Model: Frequency 50 Hz (실험적 허혈 통증 모델에서 경피신경전기자극과 간섭파전류의 진통 효과 비교 : 주파수 50 Hz를 중심으로)

  • Bae, Young-Hyeon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.13 no.6
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    • pp.2617-2624
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    • 2012
  • Interferential currents (IFC) and transcutaneous electrical nerve stimulation (TENS) are used for pain management. This study compared the analgesic effects of IFC and TENS on experimentally induced ischemic pain in otherwise pain-free subjects using a modified version of the submaximal-effort tourniquet technique. The subjects were 14 volunteers (7 male, 7 female) without known pathology that could cause pain. Their mean age was $26.7{\pm}2.0$ years. A single-blind, sham controlled, parallel-group method was used. The primary outcome measure was the change in the self-report of pain intensity during 1 of 3 possible interventions: (1) IFC, (2) TENS, or (3) sham electrotherapy. The IFC and TENS were administered on the forearm, and the sham electrotherapy group received no current output via a dummy stimulator. The results show that a 2-way repeated-measures analysis of variance revealed that there was no change in pain intensity during treatment when all 3 groups were considered together. The mean to pain intensity with the IFC intervention was no different than with TENS. Thus, Statistical analysis showed that both interventions decreased the pain intensity ratings significantly and the difference between interventions was not simply insignificant. IFC has been shown to be more comfortable than TENS in present studies and is likely to be better accepted and tolerated by patients, clinical investigation is warranted.

Effects of Non-Invasive Constant Microcurrent Stimulation on Expression of BMP-4 After Tibia Fracture in Rabbits (비침습식 미세전류자극이 토끼 경골의 골절 후 BMP-4 발현에 미치는 영향)

  • Cho, mi-suk
    • Proceedings of the Korea Contents Association Conference
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    • 2009.05a
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    • pp.1124-1129
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    • 2009
  • This study aims to examine the effects of non-invasive constant microcurrent stimulation on expression of Bone Morphogenetic Protein(BMP) 4 after tibia fracture in rabbits. Twenty four rabbits with tibia fracture were randomly divided into control and experimental groups. Each group was divided into four subgroups, based on the duration of the experiment (3, 7, 14, 28 days). The experimental groups received a constant microcurrent stimulation of $20{\sim}25{\mu}A$ intensity with surface Ag-AgCl electrode (diameter 1cm, Biopac, U.S.A.) for 24 hours a day. Cathode of the microcurrent stimulator located on the tibia directly, anode of it did on the gastrocnemius muscle. Rabbits were sacrificed on each of the postoperative days 3, 7, 14, 28. To investigate how non- invasive constant microcurrent stimulation affects bone healing, immunohistochemical analysis of BMP-4 was performed at each point. After evaluation, the test results are as follows: Comparisons of immunohistochemical observation of BMP-4 in 7 days after tibial fracture show that there was shown to be a moderate positive reaction (++) on concentric circles of Harversian system andt he interstitial lamella in the control group, while there was a very strong positive reaction (++++) on concentric circles of Harversian system and interstitial lamellain the experimental group. These results suggest that applying non-invasive constant microcurrent stimulation on fractured bone is helpful to bone healing.

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