• The Korean Journal of Physiology
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• v.22 no.1
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• pp.13-29
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• 1988

In order to elucidate the regulatory mechanism of intracellular calcium ion concentrations, contractions or contractures induced by $Na^{+}-removal$, calcium-application or ouabain-treatment as an index of $Na^+/Ca^{2+}$ exchange activity were studied in atrial muscle or vascular smooth muscle (aorta and renal artery) of the rabbit. The magnitude of low sodium contractures in atrial trabeculae increased with sigmoid shape when external sodium concentrations were reduced to sodium-free condition, whereas that of calcium contracture intensified in a parabolic pattern when external calcium concentrations were elevated to 8 mM. $Na^{+}-removal$ contractures were induced in a duration-dependent manner to $K^{+}-free$ exposure and same findings were observed with ouabain treatment. $Na^{+}-free$ contractures were not affected by verapamil treatment, but stimulated by $100{\mu}M\;Mn^{2+}$ and inhibited by high concentrations of $Mn^{2+}\;(2{\sim}8mM)$ in a dose-dependent manner. Ryanodine which is known to suppress the release of calcium from internal store abolished spontaneous twitch contractions induced by $K^{+}-free$ solution, but had no effect on the development $Na^{+}-free$ contractures. Na-free contractures were not always induced in vascular smooth muscle preparations. Contractures by $O\;mM\;Na^+$ were usually seen in aorta, but not often in renal artery.$50\;mM\;K^+$, noradrenaline (NA) and angiotensin II (AII) always evoked very large contraction in all preparations of vascular smooth muscle. Contractures developed by $O\;mM\;Na^+$ were not sensitive to verapamil treatment as in atrial trabeculae, but were abolished by $100{\mu}M\;Mn^{2+}$. In contrast to $Na^{+}-free$ contractures, $Mn^{2+}(100{\mu}M)$ had no effect on the contractures induced by NA or 50 mM$K^+$. Caffeine in the concentration of 10 mM evoked transient contracture in the distal renal artery. The rate of spontaneous relaxation in caffeine contracture was dependent upon the concentrations of external sodium, and had double component of relaxation when the rate of relaxation was plotted in the semilogarithmic scale of relative tension versus time. Especially late components of relaxation had more direct relation to $Na^+$ concentrations. It could be concluded that $Na^+/Ca^{2+}$ exchange mechanism in the heart has a large capacity, inhibited by $Mn^{2+}$ but not by verapamil and ryanodine, while $Na^+/Ca^{2+}$ exchange system in vascular smooth muscle has a very low capacity especially in small artery, inhibited by low concentration of $Mn^{2+}\;(100{\mu}M)$ but not affected by verapamil and ryanodine.

• Korean Journal of Applied Biomechanics
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• v.19 no.1
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• pp.139-148
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• 2009

D. W. HAN. Y. R. AHN., N. J. LEE and E. J. LEE. Effects of Combined Restistance Training Program of Concentric and Eccentric Contraction Using Theraband on Shoulder Rotation Torque Max and Peak Power. Korean Joumal of Sport Biomechanics, Vol. 19, No. 1, pp. 139-148, 2009. The purpose of this study was to find out that combined concentric with eccentric resistance training program using Thera-Band was more effective than only concentric resistance training program on shoulder rotation torque max and peak power. 30 female students were randomly assigned to 3 equal group; concentric and eccentric, concentric, non training group. Subjects were tested in concentric and eccentric torque max and peak power of internal and external rotation using a CON-TERX isokinetic dynamometer. Subjects in training group participated in their regular five times a week for 4 weeks. After exercise, in concentric and eccentric training group, concentric and eccentric torque max, and peak power of internal rotator at 60 deg/sec were increased significantly. concentric peak power at 120 deg/sec were increased significantly. In concentric training group, only concentric peak power of internal rotator at 60 and 120 deg/sec was increased. In conclusion, we found out that combined concentric with eccentric resistance training program using Thera-Band was more effective than only concentric resistance training program on shoulder rotation torque max and peak power.

• Journal of The Korean Society of Integrative Medicine
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• v.10 no.4
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• pp.175-185
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• 2022

Purpose : This study was conducted to determine the effect of Kegel exercise using a pressure biofeedback unit (PBU) for 2 weeks on maximum voluntary ventilation (MVV) and abdominal muscle thickness based on previous studies. Methods : The subjects of this study were 20 healthy female students in their 20s. Subjects were randomly assigned to two groups. Eleven subjects were assigned to the experimental group (EG) and 9 subjects were assigned to the control group (CG). Subjects measured MVV with a spirometer. In hooklying position, transverse abdominis (TrA), internal oblique (IO), and external oblique (EO) of the dominant side were measured using ultrasound. For the measurement value, the average value of three times was adopted. After 2 weeks of intervention, the measurements were measured in the same way. In the EG, pelvic setting training using PBU was performed before Kegel exercise. The PBU was first placed at the waist in the Kegel exercise position and the starting pressure was set at 40 mmHg and adjusted to 60 mmHg through pelvic floor muscle contraction. After performing pelvic control using PBU, Kegel exercise was performed with 8 seconds of contraction, 8 seconds of relaxation, and 3 sets of 10 reps per set. A significance level of 𝛼=.05 was used to verify statistical significance. Results : In the variable of MVV, a significant increase was confirmed in the EG (p<.05). In the abdominal muscle thickness variable, significant increases were confirmed in IO and TrA in the EG (p<.05). In addition, a significant increase in IO was confirmed in the CG (p<.05). Significant increases in IO and TrA were confirmed between groups (p<.05). Conclusion : Based on the previous study, this study confirmed that Kegel exercise using a PBU had a positive effect on MVV and abdominal muscle thickness based on a 2-week intervention.

• Journal of Adhesion and Interface
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• v.25 no.1
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• pp.169-274
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• 2024

Recent attention has been drawn to materials that undergo reversible expansion and contraction in response to external stimuli, leading to morphological changes. These materials hold potential applications in various fields including soft robotics, sensors, and artificial muscles. In this study, a novel material capable of responding to high temperatures for protection or encapsulation is proposed. To achieve this, liquid crystal elastomer (LCE) with nematic-isotropic transition properties and polyimide (PI) with high mechanical strength and thermal stability were utilized. To utilize a solution process, a dope solution was synthesized and introduced into micro-printing techniques to develop a two-dimensional pattern of LCE/PI bilayer structures with sub-millimeter widths. The honeycomb-patterned LCE/PI bilayer mesh combined the mechanical strength of PI with the high-temperature contraction behavior of LCE, and selective printing of LCE facilitated deformation in desired directions at high temperatures. Consequently, the functionality of selectively and reversibly encapsulating specific high-temperature materials was achieved. This study suggests potential applications in various actuator fields where functionalities can be implemented across different temperature ranges without the need for electrical energy input, contingent upon molecular changes in LCE.

• PNF and Movement
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• v.16 no.2
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• pp.295-300
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• 2018

Purpose: This study aimed to determine whether the abdominal muscles, which are the major lumbar stabilizers along with the respiratory muscles, are affected by smoking. We compared abdominal muscle activity between smokers and non-smokers during the sit-to-stand movement. Methods: A total of 28 healthy adult males (14 smokers and 14 non-smokers) in their 20s-30s voluntarily participated in the study. The subjects performed the sit-to-stand movement, and then their abdominal muscle activity was measured. The surface electromyography system was employed to measure the maximal voluntary isometric contraction (MVIC) values of the subjects' rectus abdominis, external oblique abdominal, internal oblique abdominal, and transversus abdominis muscles. Then, the values were quantified into %MVIC. Results: The activity of the rectus abdominis muscle was higher in the smokers than in the non-smokers. Conversely, the activity of the internal oblique abdominal and transversus abdominis muscles, which are deep abdominal muscles, was higher in non-smokers than in smokers, but the difference was not statistically significant. Conclusion: Smoking can inhibit the activity of smokers' deep abdominal muscles and increase the activity of their superficial muscles, thus making it detrimental to their musculoskeletal system.

• Physical Therapy Korea
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• v.19 no.3
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• pp.1-10
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• 2012

The aim of this study is to compare measurements of abdominal muscle thickness using ultrasonography imaging (USI) to those using a special transducer head device, during five different trunk stabilization exercises, ultimately to determine which exercise led to the greatest muscle thickness. Thirty eight healthy subjects participated in this cross-sectional study. The five types of trunk stabilization - i.e., a sit-up on the supine, an upper and lower extremity raise with quadruped on the prone, a leg raise in sitting on the ball, trunk rolling on the ball, and balance using sling on the prone position - were each performed with an abdominal draw. The thickness of the abdominal muscle - including the transverse abdominal (TrA), internal oblique (IO), and external oblique (EO) - was measured by USI with a special transducer head device, at rest and then at contraction in each position. Data were analyzed using one-way repeated ANOVA with the level of significance set at ${\alpha}$=.05. The results were as follows: 1) the TrA thickness was statistically significant (p<.05), whereas the IO and EO thicknesses were not (p>.05); 2) among the five types of trunk stabilization, TrA thickness significantly increased with the balance using a sling in the prone position, (p<.05), whereas no significant difference was noted for the four types of trunk stabilization (p>.05); 3) reliability data showed that there was a high degree of consistency among the measurements taken using the special transducer head device (ICC=.92). In conclusion, the balance using a sling in the prone position was more effective than any of the four other types of trunk stabilization in increasing TrA thickness in healthy subjects.

• Physical Therapy Korea
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• v.17 no.1
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• pp.1-8
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• 2010

The purpose of this study was to compare EMG activity for pectoralis major muscle during shoulder movement with various abduction angle and rotation position in supine position. Fifteen healthy subjects were recruited for this study. All subjects performed shoulder horizontal adduction holding a 2 kg dumbbell in shoulder abduction $40^{\circ}C$, $70^{\circ}C$, $90^{\circ}C$, $130^{\circ}C$, $160^{\circ}C$ with shoulder neutral, internal rotation (IR), and external rotation (ER). Surface EMG activity was recorded from pectoralis major clavicle part and pectoralis major sternum part for 5 seconds and EMG activity was normalized to the value of maximal voluntary isometric contraction (%MVIC). Dependent variables were examined with 3 (Neutral, IR, ER) ${\times}$ 5 ($40^{\circ}C$, $70^{\circ}C$, $90^{\circ}C$, $130^{\circ}C$, $160^{\circ}C$) analysis of variance with repeated measures. The EMG activity of pectoralis major muscle was significantly different between shoulder abduction angles and between shoulder rotation positions (p<.05). The highest value of EMG activity of pectoralis major clavicle part among shoulder abduction angles was in $70^{\circ}C$ and, $90^{\circ}C$ in that order. The highest value of EMG activity of pectoralis major sternum part among shoulder abduction angles was in $130^{\circ}C$ and, $90^{\circ}C$ in that order. According to the rotation degree, shoulder ER showed the highest value and IR showed the lowest value in both muscle parts. These results suggest that shoulder abduction $70^{\circ}C$, $90^{\circ}C$, $130^{\circ}C$ will be effective during manual muscle testing (MMT) and strengthening exercise for pectoralis major muscle. It is also supposed that shoulder ER is the efficient posture for strengthening of pectoralis major muscle.

• Clinics in Shoulder and Elbow
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• v.1 no.1
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• pp.78-82
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• 1998

The following will describe a method of evaluating the SLAP lesion in the recurrent anterior dislocation of the shoulder. We have named it the biceps load test. The biceps load test is performed with the patient in the supine position and the arm to be examined is abducted 90/sup°/, and the forearm is in the supinated position. First, the anterior apprehension test is performed. When the patient become apprehensive, the patient is allowed active flexion of the elbow, while the examiner resists elbow flexion. If the apprehension is relieved or diminished, the test is negative. If aggravated or unchanged, the test is positive. A prospective study was performed, in which 75 patients who were diagnosed as having recurrent unilateral anterior instability of the shoulder underwent the biceps load test and arthroscopic examination. The biceps load test showed negative results in 64 of these patients, of which the superior labral-biceps complex was intact'in 63 cases and only I shoulder revealed a type n SLAP lesion. E]even patients with a positive test were confirmed to have type n SLAP lesions. A positive biceps load test represents an unstable SLAP lesion in a patient with recurrent anterior dislocation of the shoulder. The biceps load test is a reliable test for evaluating the SLAP lesion in the recurrent anterior dislocation of the shoulder(sensitivity: ,9] .7%, specificity: 100%, positive predictive value: 1.00 and negative predictive value: 0.98). Biceps contraction increases the torsional rigidity ?of the glenohumeral joint and long head of biceps tendan act as internal rotator of the shoulder in the abducted and externally rotated position. These stabilize the shoulder in abduction and external rotation position in the biceps load test.

• Journal of Physiology & Pathology in Korean Medicine
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• v.27 no.1
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• pp.34-42
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• 2013

Our study is to review Chinese traditional medicine's journals about the diagnosis and treatment of spasmodic torticollis such as category, syndrome differentiation, acupoints of treatment, and herbal medicine. The journal search was performed using the search engine of China Academic Journal (CAJ) and China Doctor/Master's Dissertation (CDMD) in China National Knowledge Infrastructure (CNKI) from January 1982 to October 2012. Searching key words were the diverse combination of "spasmodic torticollis", "cervical dystonia", "Chinese traditonal medicine", "herbal medicine", "acupuncture", and "syndrome differentiation". The inclusion criteria was all kinds of journals including Chinese traditional medicine approach except for experiment study. The category, syndrome differentiation, acupoints of treatment, and herbal medicine from finally selected journals were extracted and summarized. The fourty-seven Chinese journals were selected finally. The category was divided into wind syndrome, trembling syndrome, convulsive syndrome, and convulsions. The syndrome differentiation was classified as internal stirring of liver wind, yin-blood depletion, invasion of external contraction, uncontrol of governor vessel, internal obstruction of phlegm turbidity, dual deficiency of qi and blood, and blood stasis due to qi stagnation. The combination of acupoints to unblock the meridian and dissipate binds and to tonify governor vessel and repel tremor was mainly used in acupuncture treatment. Galgun-tang or galgun-tanggami was primarily used and the others were the prescriptions to tonify liver and kidney, to calm convulsion, and to dispeling wind-phlegm. We suggests that spasmodic torticollis could be treated using Korean medicine's approach in Korea.

• Journal of Physiology & Pathology in Korean Medicine
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• v.27 no.5
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• pp.578-586
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• 2013

The objective of this study was to investigate the diagnosis and treatment of Sjogren's syndrome(SS) such as syndrome differentiation and herbal medicine by reviewing Chinese traditional medicine's journals. The journal search was carried out using China National Knowledge Infrastructure(CNKI) and PubMed from January 2007 to July 2012. Searching key words were the various combination of "Sjogren's syndrome", "Traditional Chinese Medicine", "herbal medicine", and "syndrome differentiation". The final selection of 57 studies were extracted and summarized by two researchers independently. The syndrome differentiation was classified as yin deficiency with fluid depletion, yin deficiency with dryness heat, dryness toxin with yin damage, internal obstruction of static blood, dual deficiency of qi and yang, dampness-heat obstructing, wind with external contraction, liver qi depression, blood deficiency and wind-dryness, dual deficiency of yin and yang, and internal obstruction of phlegm-blood stasis. Liriope platyphylla(麥門冬), Rehmania glutinosa(生地黃), and Scrophularia buergeriana(玄蔘) were primarily prescribed to tonify yin, engender fluid and moisten dryness.