This experiment was designed to explore specific functional relationship between the vestibular canals and the extraocular oblique muscles by observing the isometric tension responeses of the muscles to the selected vestibular canal excitation. The vestibular excitation was simulated by either stimulation of the individual canal nerve or endolymphatic fluid displacement in each canal. Each canal nerve was subjected to square wave pulses with a monopolar wire electrode placed closely to the ampullary nerve endings for electrical stimulation, and a fine stainless cannula was introduced into the each canal toward the ampulla and a minute amount $(0.5{\sim}3.5\;microliter)$ of fluid was injected in or ejected out by means of a microsyringe connected to the cannula to produce ampullopetal or ampullofugal displacement of endolymphatic fluid. The superior oblique muscle was contracted by the excitation of homolateral canals and was relaxed by contralateral canals. On the contrary, the inferior oblique was contracted by the contralateral canals and was relaxed by the homolateral canals. Summation of excitatory and inhibitory canal effects from the bilateral vestibular system was demonstrable on the tension changes of the oblique muscles. Excitation of either dual or triple canals of the unilateral vestibular system also caused summation effect on the tension response of the oblique pair; thus multiple signals from the different ampullary receptors seems to be converged into the relevant ocular motor muclei. Since the superior and inferior obliques are known to receive their motor fibers from the contralateral trochlear nuclei and intermediate nuclei of the homolateral oculomotor complex respectively, the above experimental evidences indicate that the ocular motor nuclei for oblique muscles receive excitatory signals from the contralateral vestibular canals and inhibitory signals from the homolateral canals.
Active straight-leg raise (ASLR) is a physical evaluation procedure to test lumbar spine stability. Several previous studies have reported various methods to control the activation of abdominal muscles during ASLR. We investigated the effects of three different hip positions in frontal plane on abdominal muscles to increase or decrease the difficulty level of lumbar spine stability exercise during ASLR in pain free subjects. Eleven young and healthy subjects voluntarily participated in this study (6 men, 5 women; mean age=$24.0{\pm}1.2$ years, height=$160.0{\pm}7.3cm$, weight=$55.0{\pm}10.6kg$, body mass index=$21.5{\pm}2.3kg/m^2$). The subjects had three trials on each ASLR with hip $10^{\circ}$ adduction, neutral hip, and hip $30^{\circ}$ abduction. Separate repeated-measures analysis of variance (ANOVA) and the post hoc Bonferroni tests (with ${\alpha}$=.05/3=.017) were performed for each muscle among the three different hip positions in frontal plane (ASLR with hip $10^{\circ}$ adduction, neutral hip, and hip $30^{\circ}$ abduction). The ipsilateral external oblique (EO), contralateral EO, ipsilateral internal oblique/transverse abdominis (IO/TrA), and contralateral IO/TrA were significantly greater in ASLR with hip $30^{\circ}$ abduction compared with ASLR with hip $10^{\circ}$ adduction. Also, the ipsilateral EO, contralateral EO, and ipsilateral IO/TrA were significantly greater in ASLR with hip $30^{\circ}$ abduction compared with ASLR with neutral hip. These results suggest that ASLR with hip $30^{\circ}$ abduction and neutral would be useful method to strengthen the EO and IO/TrA. And, ASLR with hip $10^{\circ}$ adduction would be effective in early stages of lumbar stabilization program due to low activation of EO and IO/TrA during maintaining of ASLR position with low load.
Journal of The Korean Society of Integrative Medicine
/
v.7
no.4
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pp.131-140
/
2019
Purpose : The purpose of this study was to investigate the interrelationship between eye movement and auditory function through the effects of eye lateralization on transient evoked otoacoustic emissions of auditory function. Methods : 25 subjects with complete set of ears were used in this study, which composed of 12 males and 13 females with pure tone threshold of below 25 dB without otolaryngology were evaluated. Each of the patient has a visual acuity of greater than 1.0 after correction, and has no problems with eye disease, eye movement, and human parallel system. In a dark silent room, the subjects sat on a chair with their heads fixed on a headrest. The tests were performed by asking the patients to look at a fixed red light dot on a light bar in front of them. This light was directed to the front, right and left sides of the subject at an angle of 40 ° In the presence of the stimulus sound in the ipsilateral ear, the transient evoked otoacoustic emissions of the ipsilateral ear was measured at the straight, right and left fixation. In order to evaluate the transient evoked otoacoustic emissions through the efferent auditory pathway, the transient evoked otoacoustic emission values of the contralateral ear were measured at the straight, right and left fixation. These measurements were taken at frequencies of 1 kHz, 1.4 kHz, 2.0 kHz, 2.8 kHz and 4 kHz, respectively. Results : Transient evoked otoacoustic emissions caused by lateral movement of the eye showed significant changes at 1.4 KHz and 2 KHz of the afferent pathway of the ipsilateral ear. Also, significant changes were observed at 1.4 KHz and 4 KHz of the efferent pathway of the contralateral ear. Conclusion : These results indicated that there is a close relationship between eye movement and auditory cochlea. In the future, further studies considering more diverse subjects and age groups will be needed.
Journal of the Korean Society of Physical Medicine
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v.10
no.3
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pp.101-108
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2015
PURPOSE: This study researched the effects of the changes of elbow joint angle and of arm position in PNF pattern on muscle activation of the contralateral shoulder muscles while performing PNF pattern exercise. METHODS: The research subjects were 16 male physical therapists who had no neuromuscular or neurological disorders. To measure the muscle activation of the contralateral shoulder muscles, EMG electrodes were attached to the muscle valley of the middle and posterior areas of the deltoid and triceps muscles of the arm. Muscle activation while performing the ulnar thrust PNF pattern exercise was measured with the elbow joint positioned at angles of $30^{\circ}$, $45^{\circ}$, and $60^{\circ}$. Resistance points were at the initial, middle, and end ranges of PNF pattern exercise. RESULTS: Muscle activation of the middle and posterior portions of the deltoid muscle increased significantly according to the changes of elbow joint angle. In each resistance point the middle range was significantly higher than at other points. A significant difference on muscle activation was demonstrated throughout each range depending on the type of muscle. Muscle activation of the middle and posterior portions of the deltoid muscle was higher than muscle activation of the triceps. CONCLUSION: The results of this study demonstrate that the PNF pattern exercising method used in this study is a selective exercising method focusing on the deltoid muscle over the triceps muscle. In order to increase the muscle strength to the maximum level, it is necessary to provide the maximum level of resistance in the middle range of the elbow joint.
Joo, Chan Seong;Park, Su Yeon;Kim, JongSik;Choi, Byeong Gi;Chung, Yoonsun;Park, Won
The Journal of Korean Society for Radiation Therapy
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v.27
no.2
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pp.175-181
/
2015
Purpose : To evaluate Contralateral Breast Doses with Supine and Prone Positions for tangential Irradiation techniques for left-sided breast Cancer Materials and Methods : We performed measurements for contralateral doses using Human Phantom at each other three plans (conventional technique, Field-in-Field, IMRT, with prescription of 50 Gy/25fx). For the measurement of contralateral doses we used Glass dosimeters on the 4 points of Human Phantom surface (0 mm, 10 mm, 30 mm, 50 mm). For the position check at every measurements, we had taken portal images using EPID and denoted the incident points on the human phantom for checking the constancy of incident points. Results : The contralateral doses in supine position showed a little higher doses than those in prone position. In the planning study, contralateral doses in the prone position increased mean doses of 1.2% to 1.8% at each positions while those in the supine positions showed mean dose decreases of 0.8% to 0.9%. The measurements using glass dosimeters resulted in dose increases (mean: 2.7%, maximum: 4% of the prescribed dose) in the prone position. In addition, the delivery techniques of Field-in-field and IMRT showed mean doses of 3% higher than conventional technique. Conclusion : We evaluated contralateral breast doses depending on different positions of supine and prone for tangential irradiations. For the phantom simulation of set-up variation effects on contralateral dose evaluation, although we used humanoid phantom for planning and measurements comparisons, it would be more or less worse set-up constancy in a real patient. Therefore, more careful selection of determination of patient set-up for the breast tangential irradiation, especially in the left-sided breast, should be considered for unwanted dose increases to left lung and heart. In conclusion, intensive patient monitoring and improved patient set-up verification efforts should be necessary for the application of prone position for tangential irradiation of left-sided breast cancer.
Background: Peripheral nerve injuries are commonly encountered clinical problems and often result in severe functional deficit. Bee venom acupuncture has traditionally been used to treat several inflammatory diseases and chronic pain conditions. Objectives: The aims of this study were to compare the effects of bee venom (general bee venom, BV) and sweet bee venom (allergen-removed bee venom, SBV) acupuncture on the recovery rate of locomotor function, the expression of brain-derived neurotrophic factor (BDNF) in the sciatic nerve, and the expression of c-Fos in the brain following sciatic crushed nerve injury in rats, and to evaluate differences due to administration areas. Method: Walking track analysis, Western blot for BDNF and tyrosine receptor kinase B (TrkB), and immunohistochemistry for c-Fos were performed. In this study, comparative analyses of the effects of BV and SBV acupuncture in relation to administration sites, contralateral side or ipsilateral side, were conducted. Results: In the present result, sciatic function index (SFI) in walking track analysis significantly decreased following sciatic crushed nerve injury. The expressions of BDNF and TrkB in the sciatic nerve increased after induction of sciatic crushed nerve injury. C-Fos expression in the ventrolateral periaqueductal gray (vlPAG) and paraventricular nucleus (PVN) also increased. BV and SBV acupuncture treatment improved the SFI in walking track analysis. Treatment with SBV at 1mg/kg showed more potent enhancing effect on SFI compared to BV. Treatment with 1mg/kg BV or 1mg/kg SBV acupuncture suppressed the BDNF and TrkB expression in the sciatic nerve. BV and SBV acupuncture treatment also suppressed c-Fos expression in the PVN and vlPAG regions. Treatment with SBV at 1mg/kg showed more potent suppressing effect on c-Fos expression compared to BV when injected into the contralateral side of the injured nerve. Generally we could not find significant difference in the effects between contralateral side and ipsilateral side of the injured nerve. Conclusion: We have shown that BV and SBV acupuncture treatment can be used as the effective therapeutic modality to ameliorate the symptoms of sciatic crushed nerve injury.
Objectives : The purpose of this study was to determine whether electroacupuncture(EA) is effective in reducing pain on the severe ankle sprain classified as grade 3 in rats. Methods : The severe(grade 3) ankle sprain model was induced surgically by ankle ligament injury(the anterior talofibular, the calcaneofibular and the posterior talofibular) in the Sprague-Dawley rats(180~250 g). The effects of EA on weight bearing forces(WBR) of the affected foot were examined in a rat model of ankle sprain. EA was applied to either SI6, ST37, GB34, GB39 or GB42 acupoints by trains of electrical pulses(2 Hz, 1 ms pulse width, 2 mA intensity) for 15 min. Results : Cutting of the lateral ankle ligament complex produced the severe ankle sprain symptoms as grade 3. EA of the contralateral SI6 resulted in more analgesic effect than one of ipsilateral SI6 even though there was significant effect. EA of the ipsilateral GB34 and GB39 produced potent analgesic effects on the surgical ankle sprained pain behaviors. However, there were no significant analgesic effects in the contralateral GB34 and GB39 EA groups. In addition, both side of ST37 and GB42 did not result in analgesic effect on the surgical ankle sprained rat. Conclusions : The data suggest that EA induced analgesia shows point specificity on the severe ankle sprained pain model classified as grade 3.
Objectives: Warm needling combines simultaneously the effects of acupuncture and moxibustion. This study was to investigate whether warm needling could relieve acute knee arthritis induced by carrageenan in rats. Methods: To illuminate the underlying mechanisms of the warm needling-induced antinociception, weight bearing force (WBF) was observed on the acute knee arthritic rat model. Under general anesthesia, ST36, SP9, Hakjung extra point, LI4 were punctured and stimulated with 30 mg moxa ball combustion on top of the needle (${\emptyset}0.18{\times}8mm$). Results: In behavioral test, rats subsequently showed a reduced stepping force of the affected limb 3 hours after the induction of arthritis. Warm needling on the contralateral or ipsilateral ST36 failed to show antinociceptive effect on the acute knee arthritis. Warm needling on the contralateral SP9 or LI4 increased WBF values to normal level in the acute stage of the arthritis. Warm needling on the Hakjung extra-point resulted in the significant antinociceptive effects through acute stage. These effects of warm needling were suppressed by opioids receptor antagonist naltrexone (10 mg/kg, i.p.) and alpha adrenoceptor antagonist phentolamine (5 mg/kg, i.p.). Conclusion: The data suggest that warm needling-induced antinociception is differently mediated by acupoints and accomplished by activating the descending inhibitory systems including endogenous opioids and $\alpha$-adrenoceptors.
Peripheral nerve injury results in plastic changes in the dorsal ganglia (DRG) and spinal cord, and is often complicated with neuropathic pain. The mechanisms underlying these changes are not known, but these changes seem to be most likely related to the neurotrophic factors. This study investigated the effects of mechanical peripheral nerve injury on expression of brain-derived neurotrophic factor(BDNF) in the DRG and spinal cord in rats. 1) Bennett model and Chung model groups showed significantly increased percentage of small, medium and large BDNF-immunoreactive neurons in the ipsilateral $L_4$ DRG compared with those in the contralateral side at 1 and 2 weeks of the injury. 2) In the ipsilateral $L_5$ DRG of the Chung model, percentage of medium and large BDNF-immunoreactive neurons increased significantly at 1 week, whereas that of large BDNF-immunoreactive neurons decreased at 2 week when compared with those in the contralateral side. The intensity of immunoreactivity of each neuron was lower in the ipsilateral than in the contralateral DRG. 3) In the spinal cord, the Bennett and Chung model groups showed a markedly increased BDNF-immunoreactivity in axonal fibers of both superficial and deeper laminae. The present study demonstrates that peripheral nerve injury in neuropathic models altered the BDNF expression in the DRG and spinal cord. This may suggest important roles of BDNF in sensory abnormalities after nerve injury and in protecting the large-sized neurons in the damaged DRG.
Purpose: Many facial burn patients suffer from hyperpigmentation and its treatment has been challenging. Vitamin C (ascorbic acid) has important physiologic effects on skin, including inhibition of melanogenesis, promotion of collagen biosynthesis, prevention of free radical formation, and acceleration on wound healing. The purpose of this study is to evaluate the effectiveness of Vitamin C iontophoresis for the treatment of postburn hyperpigmentation. Methods: The authors performed a retrospective analysis of 93 patients who were admitted for the treatment of facial burn from February 2008 through February 2010. Among them, 51 patients were treated with Vitamin C iontophoresis to control postburn hyperpigmentation and 42 patients were not. Experimental group was chosen 20 of 51 patients who had been treated with Vitamin C iontophoresis and had normal facial skin on the comparable contralateral aesthetic unit. Control group was chosen 20 of 42 patients who were not treated with Vitamin C iontophoresis and had also contralateral normal aesthetic unit. The resulting color of 20 patients who were treated with Vitamin C iontophoresis was compared with the color of the contralateral normal facial skin using a digital scale color analysis. Results were analyzed with Wilcoxon signed rank test. Results: The analysis revealed significant improvement of hyperpigmentation in the experimental group compared to control group. The difference of intial value and the value in 6 months showed significant change. Mean (${\Delta}^{initial}$-${\Delta}^{6month}$) of experimental group was 11.61 and control group was 7.23. Thus, the difference between the experimental group and the control group was 4.38. Therefore, Vitamin C iontophoresis revealed significant improvement of hyperpigmentation in the experimental group compared with control group. Conclusion: Vitamin C iontophoresis is an effective treatment modality for postburn hyperpigmentation.
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