• Journal of Oral Medicine and Pain
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• v.32 no.4
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• pp.403-411
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• 2007

This investigation was carried out to evaluate the effect of Transcutaneous Electric Nerve Stimulation (TENS) to experimentally induced masticatory muscle pain and muscular fatigue. Twenty-nine healthy volunteers (18 men and 11 women, aged $26.1{\pm}4.7$ years) without past history or present symptoms of temporomandibular disorders were participated in this study. All of the subjects were randomly assigned to experimental group and control group, after at least 3 days interval, two groups were reassigned conversely. Subjects assigned to experimental group were received TENS and others assigned to control group were received sham-TENS therapy for 45 minutes, respectively. The changes of Visual Analogue Scale (VAS), Pressure Pain Threshold (PPT), and EMG power spectrum were measured on the masseter muscle both before and after sustained fatiguing contraction in each group. The major findings of this study are as follows : 1. PPTs and median frequencies of masseter muscles were significantly decreased after sustained isometric contraction resulting in muscular fatigue. 2. In experimental group received TENS therapy, PPTs measured both before and after occurrence of experimentally induced muscular fatigue were significantly increased. 3. In experimental group received TENS therapy, the changes of PPTs during sustained isometric contraction resulting in muscular fatigue were significantly decreased. 4. In experimental group received TENS therapy, VAS measured after occurrence of experimentally induced muscular fatigue was significantly decreased. 5. Although there were not statistical significances, endurance time was increased in experimental group received TENS therapy and decreased in control group received sham-TENS therapy. 6. In experimental group received TENS therapy, the changes of median frequencies were the less decreased and the slope of median frequency shift was the more increased during endurance time than in control group, however, there were not statistical significances.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.5 no.1
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• pp.89-101
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• 2001

The conventional pattern-methods for discrimination of acupoint, meridian line which is the basic object of diagnosis and medical treatment in oriental medicine is discriminated the conduction point by the stimulation in body skin with DC. But, it is not sufficient to truth in discrimination ratio, coincident ratio, body effect, reproductivity. Therefore, this paper is extracting the optimal parameter of frequency and waveform in order to improve the conventional pattern, and proposing the SPAC(Single Power Alternative Current) stimulus pattern applying that. Also, this algorithm proposes to be able to discriminate with low pressure of the electrode by displaying in the level meter both the absolution and relation value of the skin current. It is able to decrease pain and body effect by electrode pressure and discriminate acupoint regardless of skin current in difficult discrimination spot. It is compared the performance of system applying the extracted optimal parameter and algorithm, and it is confirmed that there is difference in discrimination parameter of acupoint reacted to the individual and the meridian. It is compared that discrimination, coincident ratio of the traditional acupoints as the acupoint stimulation pattern. It is confirmed truth of optimal parameter and discrimination algorithm. Keyword: Meridian, Discrimination, Coincident, Body effect, Reproductivity, SPAC, Optimal parameter.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.5
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• pp.548-553
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• 2007

This study was designed to investigate effects of KH-305 on erectile dysfunction in hyperlipidemic rat. KH-305 has been evaluated for antihyperlipidemic and antierectile dysfunction effects on experimental hyperlipidemic rats induced by high cholesterol-diet. After oral administration of KH-305 water extract (50, 100, 200, 300 mg/kg) to hyperlipidemic rats for 8 weeks, the variables including body weight, total cholesterol, HDL-, and LDL-cholesterol levels in serum, the expression of eNOS and nNOS in penis were measured. Also, erectile function was determined by the measurements of intracavernosal pressure (ICP) and maximal arterial pressure (MAP) after electrical stimulation of the cavernosal nerve. Oral administration of KH-305 extracts significantly inhibited the increase of serum total cholesterol and LDL-cholesterol levels and the decrease of serum HDL-cholesterol level in hyperlipidemic rats induced by high fat diet. The penile expression level of the two enzymes (eNOS, nNOS) were increased significantly after oral administration of the KH-305 extracts. Erectile function after 10 volts stimulation was significantly decreased in the hyperlipidemic rat compared with the normal rat, but increased in KH-305 group compared with hyperlipidemic group. These results suggest that KH-305 is effective for erectile dysfunction in hyperipidemia.

• Journal of The Korean Society of Integrative Medicine
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• v.8 no.4
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• pp.223-230
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• 2020

Purpose : The purpose of this study was to examine the effects of tools (i., extracorporeal shock wave therapy, massage gun, and foam roller) on range of motion, muscle tone and pain threshold among patients with hamstring stiffness. Methods : Fourteen participants with hamstrings stiffness were recruited. Interventions were performed 6 times, and each session was for 30 seconds using the three tools. The range of motion, muscle tone, and pain threshold were measured. The order of the use of the three tools was randomly determined. The foam roller was made to move from the bottom of the hip crease to the upper part of the back of the hamstring. Additionally, velocity 5 vibration stimulation was performed on the hamstring using a massage gun. Moreover, vibration stimulation was performed on the hamstring with extracorporeal shock wave therapy 5 minutes, 5 Hz, and 1,500 strokes. The flexibility of the posterior thigh muscle was based on maintaining the knee and hip joints in a 90 ° bend in the supine position. The joint angle of the knee was measured, when the knee was actively extended, at the maximum point where the posterior thigh muscle was stretched. The elasticity of the posterior thigh muscle was measured while the subject was prone and in a relaxed state without any force. Measurements were made at the muscle abdominal area of the semitendinosus muscle of the posterior femur, and the area to be measured was marked with a pen. The measurement of the tenderness threshold of the posterior femur was measured using a tenderness meter(Commander Algometer, J-Tech, USA). The force value at the point at which the pressure sensation change to pain was measured after applying vertical pressure to the posterior femur muscle, which was the halfway point between the ischial tuberosity and the popliteal surface of the subject lying on their stomach. Results : The extracorporeal shock wave therapy increased stiffness and, muscle tone, and caused changes in the pain threshold, whereas the other two tools had no effect on these indices. Conclusion : Extracorporeal shock wave therapy has important effects on range of motion and muscle stiffness and can be used in warmup protocols.

• The Korean Journal of Physiology
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• v.27 no.2
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• pp.185-197
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• 1993

The rostral ventrolateral medulla (RVLM) includes vasopressor neurons, which transmit activation signals to the intermediolateral nucleus (IML) of the spinal cord, where the preganglionic sympathetic nucleus is located, to raise arterial blood pressure (BP). However, controversy exists as to the possible depressor area in the RVLM and the pathway involved. The present study persued evidence far the location of depressor neurons and the pathway by simultaneously observing changes in BP and the firing rate (FR) of cardiovascular neurons (CVNs) in the RVLM during the somatosympathetic reflex (SSR) elicited by peripheral nerve stimulation, since CVNs are known to contribute to the generation of the sympathetic nerve discharge. In 42 cats, anaesthetized with $\alpha-chloralose$, single unit recording was performed, using carbon filament electrodes inserted into the RVLM, enabling estimation of the post R wave unit histogram (PR-UNlT) and the spike triggered average of sympathetic nerve discharge (STA-SND), allowing identification of CVNs. Antidromic stimulation of spinal $T_2$ segment was followed to determine whether the identified CVN projects axonal endings to the spinal cord (reticulospinal neuron). The sciatic nerve was electrically stimulated at $A\delta-intensity$ (1 mA, 0.1 ms), 1 Hz and C-intensity (10 mA, 0.5 ms), 20 Hz to elicit the depressor, and pressor responses of the SSR, respectively. Simultaneous measurement of CVN firing rate was made. Experimental results are summarized as follows. 1) 20 out of 98 CVNs had axonal projections to the spinal cord and 17 out of 98 CVNs showed FR changes during SSR. 2) Response patterns of FR and BP during SSR were classified into 8 types. 3) These 8 different response patterns could be further classified into those from pressor and depressor neurons. These results demonstrate that some CVNs were identifiable as reticulospinal neurons responding to anti-dromic stimulation and that CVNs operating as depressor neurons as well as pressor neurons exist in the RVLM, both of which are involved with SSR mediation. Therefore, evidence was found that an independent depressor pathway might be involved in the mediation of SSR.

• Women's Health Nursing
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• v.8 no.3
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• pp.412-423
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• 2002

This study was designed to evaluate the effect of pelvic floor muscle exercise using biofeedback and electrical stimulation after normal vaginal delivery. The data were collected from November 1999 to April 2000 at a university hospital located in Seoul, Korea. Out of 49 women with normal vaginal delivery, 25 of experimental group(with exercise) and 24 of control group(without exercise) were questioned about lower urinary symptoms, discomfort during sexual intercourse and daily life. The maximum pressure of pelvic floor muscle contraction(MPPFMC) and duration of pelvic floor muscle contraction(DPFMC) were measured at pre-treatment, the end of treatment and 8 weeks after a treatment program. The pelvic floor muscle exercise program(using biofeedback and electrical stimulation) was applied to the experimental group twice a week for 4 weeks at the incontinence clinic and the pelvic floor muscle exercise at home for that time and more 8 weeks. Data were analyzed by t-test, $x^2$-test, Fisher's exact test and the repeated measures ANOVA. The results were as follows; 1) MPPFMC(p=0.000) and DPFMC(p=0.021) were significantly increased in the experimental group. 2) In the lower urinary symptoms, daily frequency(p=0.001), nocturia(p=0.002), incontinence episode(p=0.016), stress incontinence(p=0.012), quantity of incontinence(p=0.026), straining(p=0.041), and strength of stream(p=0.009) were significantly decreased in the experimental group. 3) Discomfort during sexual intercourse had not a significant difference between the two groups, which was not significantly decreased as time passed. 4) In the discomfort during daily life, activity restriction(p=0.042), exercise restriction (p=0.008), interpersonal relationship restriction(p=0.046), and discomfort of general life(p=0.027) showed a significant difference between the two groups, which were not significantly decreased as time passed. In conclusion, it is suggested that the pelvic floor muscle exercise using biofeedback and electrical stimulation might be a safer and more effective program for the improvement of postpartum pelvic muscle contraction.

• Tunnel and Underground Space
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• v.23 no.6
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• pp.493-505
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• 2013

This numerical study investigates seismicity and fault slip induced by fluid injection in deep geothermal reservoir with pre-existing fractures and fault. Particle Flow Code 2D is used with additionally implemented hydro-mechanical coupled fluid flow algorithm and acoustic emission moment tensor inversion algorithm. The output of the model includes spatio-temporal evolution of induced seismicity (hypocenter locations and magnitudes) and fault deformation (failure and slip) in relation to fluid pressure distribution. The model is applied to a case of fluid injection with constant rates changing in three steps using different fluid characters, i.e. the viscosity, and different injection locations. In fractured reservoir, spatio-temporal distribution of the induced seismicity differs significantly depending on the viscosity of the fracturing fluid. In a fractured reservoir, injection of low viscosity fluid results in larger volume of induced seismicity cloud as the fluid can migrate easily to the reservoir and cause large number and magnitude of induced seismicity in the post-shut-in period. In a faulted reservoir, fault deformation (co-seismic failure and aseismic slip) can occur by a small perturbation of fracturing fluid (<0.1 MPa) can be induced when the injection location is set close to the fault. The presented numerical model technique can practically be used in geothermal industry to predict the induced seismicity pattern and magnitude distribution resulting from hydraulic stimulation of geothermal reservoirs prior to actual injection operation.

• Journal of Life Science
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• v.25 no.2
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• pp.231-236
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• 2015

Angiotensin II (AngII) is an essential hormone that affects vascular physiology. For example, stimulation of vascular smooth muscle cells (VSMCs) rapidly induces vasoconstriction and results in the up-regulation of blood pressure. Chronic stimulation of VSMCs with AngII also results in hypertrophy. In this study, we confirmed an involvement of phosphatidylinositol 3-kinase (PI3K)-dependent calcium mobilization in AngII-induced generation of reactive oxygen species (ROS). Stimulation of rat aortic smooth muscle cells (RASMCs) with AngII significantly induced the generation of ROS in a dose- and time-dependent manner. AngII-induced generation of ROS was completely abolished by pharmacological inhibition of PI3K (with LY294002), but inhibition of the ERK signaling pathway had no effect. AngII-induced calcium mobilization was completely blocked by inhibition of PI3K, whereas inhibition of the ERK signaling pathway by PD98059 was ineffective. Depletion of extracellular calcium or inhibition of the L-type calcium channel by nifedipine completely blocked AngII-induced calcium mobilization. Depletion of extracellular calcium by EGTA and incubation of RASMCs with calcium-free medium both significantly blocked AngII-induced ROS generation. Inhibition of the L-type calcium channel also significantly blocked AngII-induced ROS generation. These results suggest that AngII-induced ROS generation is regulated by calcium mobilization, which, in turn, is modulated by a PI3K/L-type calcium channel signaling pathway.

• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.1
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• pp.112-121
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• 2017

Large eddy simulations of transitional flows around a stud installed on a flat plate have been performed to investigate an influence of grid resolution on turbulence stimulation by the stud. Because streamwise vortical structures generated by the stud played an important role in turbulence stimulation of boundary layer, streamwise vorticity was compared in the wake region behind the stud when the number of grids increased or decreased by a ratio of ${\sqrt{2}}$ in streamwise, wall-normal and spanwise directions respectively. The streamwise vorticity was shown to be mainly affected by spanwise grid resolution (${\Delta}z^+$) rather than streamwise and wall-normal grid resolution. In a viewpoint of numerical efficiency as well as physical resolution, ${\Delta}x^+{_{min}}=7.6$, ${\Delta}x^+{_{max}}=41$, ${\Delta}y^+{_{wall}}=0.25$ and ${\Delta}z^+=7.6$ was found to be desirable. Once a grid resolution was determined in each direction, a grid verification was carried out by increasing or decreasing the grid resolution y a ratio of ${\sqrt{2}}$ in all directions. The grid uncertainties of pressure and drag coefficients were 21.6 % and 2.8 % while the corrected uncertainties were 2 % and 0.3 %, respectively.

• Journal of Yeungnam Medical Science
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• v.23 no.1
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• pp.36-44
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• 2006

Background: There is controversy regarding whether COX-2 specific inhibitors are associated with elevation of blood pressure. We compared the effects of aspirin, indomethacin, and celecoxib for vascular reactivity induced by phenylephrine. We also tested the effects of indomethacin and NO donor on COX-1 and COX-2 protein expression, as well as nitrite production in culture medium of vascular smooth muscle cells. Materials and Methods: In this experiment, we used the isometric tension study for vascular reactivity. After 45 minutes of pretreatment with aspirin, indomethacin, celecoxib, and phenylephrine induced contractions were tested. COX-1 and COX-2 protein expressions were analyzed by Western blot and nitrite production by the Griess reaction. Results: Although celecoxib pretreatment caused enhanced arterial contraction, aspirin pretreatment induced more potent arterial contraction than celecoxib in the isometric tension study of rabbit femoral artery. COX-1 protein expression was unchanged by indomethacin, SNP and NOR-3; COX-2 protein expression was increased by the addition of indomethacin, SNP, and NOR-3. Especially, NOR-3, a NO donor, significantly increased COX-2 protein expression with unstimulated conditions as well as LPS stimulation. Induction of nitrite production was higher with NOR-3 treatment than SNP treatment with LPS stimulation. Conclusion: These results suggest that aspirin caused more potent vascular contraction than celecoxib and indomethacin. COX-2 expression in VSMC depended on the types of NO donor and LPS stimulation.