• The Korean Journal of Physiology and Pharmacology
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• 제2권2호
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• pp.217-223
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• 1998

Oxygen-derived free radicals have been implicated in many important functions in the biological system. Electrical field stimulation (EFS) causes arterial relaxation in animal models. We found that EFS applied to neither muscle nor nerve but to Krebs solution caused a relaxation of rat aorta that had been contracted with phenylephrine. In the present study, therefore, we investigated the characteristics of this EIRF (electrolysis-induced relaxing factor) using rat isolated aorta. Results indicated that EIRF acts irrespective of the presence of endothelium. EIRF shows positive Griess reaction and is diffusible and quite stable. EIRF-induced relaxation was stronger on PE-contracted aorta than on KCl-contracted one, and inhibited by the pretreatment with methylene blue. Zaprinast, a cGMP-specific phosphodiesterase inhibitor, potentiated the EIRF-induced relaxation. $N^G-nitro-L-arginine$, NO synthase inhibitor, did not inhibit the EIRF-induced relaxation. Deferroxamine, but not ascorbic acid, DMSO potentiated the EIRF-induced relaxation. These results indicate that electrolysis of Krebs solution produces a factor that relaxes vascular smooth muscle via cGMP-mediated mechanism.

• The Journal of Korean Physical Therapy
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• 제9권1호
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• pp.185-193
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• 1997

The purpose of this study was to investigate the neurophysiological mechanisms, assessment of muscle spasm and treatments that could apply to clinical field. Spasm is a painful pattern of contraction of muscle caused by chronic or acute trauma, excessive tension, or organic disorders. Aside from pain, muscle spasm creates shortenning of muscles and limits motion. Untreated spasm and protective immobility due to pain lead to decreased local blood flow in the muscles and result in a vicious cycle of muscle spasm and paul. The assessment of muscle spasm involve muscle tone assessment, tissue compliance, and joint ROM. Each of these aessessments utilize as a part of the patient's condition Clinical managements involve drug management and physical therapy. Expecially, physical therapy is one of the most important techniques to reduce muscle spasm. Physical therapy includes applying heat and cold, electrical stimulation, massage, and traction. This investigation should entourage phisical therapists to experiment further with various techniques to reduce muscle spasm.

• Journal of Acupuncture Research
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• 제33권3호
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• pp.117-127
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• 2016

Objectives : This study was performed to observe the effect of complex therapy, including electro-acupuncture and magnetic-acupuncture, on peripheral facial nerve palsy. Methods : Nine patients with peripheral facial nerve palsy were treated with acupuncture using electrical and magnetic stimulation. Acupoints in the face were stimulated with an electromagnetic field, as widely and as evenly as possible. To evaluate the effects before and after treatment we used Yanagihara's unweighted grading system, House-Brackmann scale, and Sunnybrook facial grading system and image once a week. Results : After treatment, the scores of Yanagihara's unweighted grading system, House-Brackmann scale and Sunnybrook facial grading system each improved (p-value < 0.05). Conclusion : Complex therapy using electro-acupuncture and magnetic-acupuncture might be an effective treatment to improve symptoms of peripheral facial nerve palsy. Further randomized-controlled trials are required to verify the efficacy and results of this study.

• 한국산업보건학회지
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• 제32권4호
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• pp.381-392
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• 2022

Objectives: Objective of this study is to review briefly exposure characteristics, monitoring instruments and threshold limit values for extremely low frequency-magnetic field (ELF-MF) methods. This study was undertaken through brief literature review. We performed a literature search in PubMed to identify ELF-MF studies conducted in workplaces. Initial search keywords such as 'extremely low frequency-magnetic field (ELF-MF)' and 'electromagnetic fields (EMF)' combined or singly. We limited our review to occupational rather than general nonworkplace environmental exposures. Methods: The contents we reviewed: key industry and occupations generating ELF-MF, several direct-reading instruments monitoring ELF-MF and threshold limit values (TLV) preventing health effects may be caused by the exposure to ELF-MF. Results: The industries related to the generation and supply of electricity, electrolytic installations, welding, and induction heating and more were regarded as high ELF-MF exposure industries. All jobs handling or employed performed in power cable lines, electrical wiring, and electrical equipment are found to be exposed to ELF-MF. Threshold or ceiling limit, 1,000 µT, is established to prevent acute effects of exposure to low-frequency EMFs on the nervous system: the direct stimulation of nerve and muscle tissues and the induction of retinal phosphenes. The International Agency for Research on Cancer (IARC) has classified ELF-MF as possibly carcinogenic to humans chiefly based on epidemiological studies on childhood leukemia. However, a causal relationship between magnetic fields and several types of cancer including childhood leukemia has not been established nor has any other long-term effects. Risk management using precautionary measures, has been initiated by the US and EU to prevent chronic health effects related to ELF-MF exposure in workplaces. Conclusion: This study recommends the implementation of various measures such as theestablishment of occupational exposure limit values for ELF-MF and precautionary principle to prevent potential chronic occupational health effects may be caused by ELF-MF in Korea.

• 대한약리학회지
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• 제30권1호
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• pp.67-73
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• 1994

Na-Ca 교환은 calcium 이온을, 세포 내외의 Na 이온 농도차에 의해서 형성되는 원동력의 방향에 따라, 세포내로(역방향 Na-Ca 교환), 혹은 세포밖으로(정방향 Na-Ca 교환) 이동시킨다. 그러므로 Na-Ca 교환은 심근 수축 운동의 조절 기전의 하나로 받아 들여지고 있다. 그러나, 세포내의 Na 이온 농도는 항상 세포외의 농도보다 낮으므로, 역방향 Na-Ca 교환의 존재와 아울러 이의 심근 수축에 있어서의 역할 가능성에 대해 많은 연구자들이 회의를 가지고 있는 것이 사실이다. 그러므로 본 연구는 흰쥐의 좌심방을 이용하여, 역방향 Na-Ca 교환의 존재 여부와 그 역할의 존재 가능성을 추구하여 보고자 하였다. 흰쥐의 좌심방은 전기장 자극(0.5msec, supramaximal voltage)으로 수축을 유발하고, 자극 빈도를 안정시 4Hz에서 0.4, 1, 8Hz로 변동시킬때 그 수축 장력에서 특징적인 역 사다리 효과(negative staircase effect)가 나타내었으나, 이때 $^{45}Ca$ 섭취는 저빈도로 갈수록, 또한 고빈도로 갈수록 증가되는 이원적인 증가를 나타내었다 자극 빈도를 4Hz 에서 0.4Hz로 변동시에는 수축 장력이 특징적인 삼단계 변환, 즉 급격히 증가하는 첫단계에 이어 급격하게 감소하는 이단계와 안정되어지는 삼단계로 나타났다. $^{45}Ca$ 섭취도 장력 변동과 같은 양상으로 처음 30초 동안에 현저하게 증가한 후 감소되었다. Na-Ca 억제 약물인 benzamil은 $10^{-5}M$에서부터 $3{\times}10^{-4}M$까지 용량에 비례하여 특히 초기의 장력증가를 봉쇄하였다. Bay K-8644$(3{\times}10^{-5}M)$ 처치는 자극 빈도 감소에 따른 수축력 증가를 현저하게 항진시켰으며, benzamil처치는 이때에도 억압을 나타내었다. Verapamil $3{\times}10^{-5}M$ 전처치시에는 4Hz 자극시의 수축 운동은 완전히 소실시켰으나, 0.4 혹은 1 Hz로 바꿈에 따라 수축 운동이 재현되었다. 이때 $^{45}Ca$ 섭취는 verapamil을 전처치하지 않은 경우보다 현저하게 항진되었다. 이상의 결과로 보아, 흰쥐의 좌심방에서 자극 빈도 감소후에는, 먼저 역방향 Na-Ca 교환에 의해 calcium이온이 세포내로 유입되어 수축운동의 항진이 유발되고, 이어 Na-Ca 교환이 정방향으로 변환되어 calcium이온을 세포밖으로 유출시킴에 따라 수축 운동이 감소된다고 생각한다.

• 동의생리병리학회지
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• 제33권6호
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• pp.356-362
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• 2019

Scutellaria baicalensis (SB) has widely used in the treatment for various brain diseases in the field of Oriental medicine. Biofermantation of SB can make major chemical constituents of SB to pass blood-brain barrier easily and to have more potent anti-oxidant ability. There is a little information about the contribution of fermented SB (FSB) to the formation or maintenance of the neural plasticity in the hippocampus. The purpose of this study was to evaluate effects of FSB extract on hydrogen peroxide (H₂O₂) - induced impairments of the induction and maintenance of long-term potentiation (LTP), an electrophysiological marker for the neural plasticity in the hippocampus. From hippocampal slices of rats, the field excitatory postsynaptic potentials (fEPSPs) were evoked by the electrical stimulation to the Schaffer collaterals - commissural fibers in the CA1 areas and LTP by theta-burst stimulation by using 64 - channels in vitro multi-extracellular recording system. In order to induce oxidative stress to hippocampal slices two different concentrations (200, 400 μM) of H₂O₂ were given to the perfused aCSF before and after the LTP induction, respectively. The ethanol extract of FBS with concentration of 25 ㎍/ml, 50 ㎍/ml was diluted in perfused aCSF that had 200 μM H₂O₂, respectively. Oxidative stress by the treatment of H₂O₂ resulted in decrease of the induction rate of LTP in the CA1 area with a dose - dependent manner. However, the ethanol extract of FSB prevented the reduction of the induction rate of LTP caused by H₂O₂ - induced oxidative stress with a dose - dependent manner. These results may support a potential application of FSB to ameliorate impairments of hippocampal dependent neural plasticity or memory caused by oxidative stress.

• 대한약리학회지
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• 제28권1호
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• pp.49-60
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• 1992

선천성 고혈압 흰쥐(SHR)에서 endothelin-1(ET)과 neuropeptide Y(NPY) 투여에 의한 심혈관계 반응에 미치는 enallapril 장기처치의 영향을 검토하였다. 생후 6주의 SHR에 enalapril(3 mg/kg/day)을 6주간 투여하였을 때 고혈압 발현이 현저히 억제되었다(이하 enalapril 처치군). Enalapril 처치군에서 ET 및 NPY에 의한 승압반응이 현저히 억제되었지만, ET 측뇌실투여에 의한 혈압상승 및 NPY측뇌실 투여로 야기되는 혈압하강효과에는 영향이 없었다. 뇌척수제거 흰쥐에서 전기적 자극으로 야기되는 빈맥효과는 enalapril처치나 ET투여로 억제되었는데, ET의 작은 ${\alpha}_2$-수용체 길항제인 yohimbine 전처치로 봉쇄되었다. SHR의 적출 대동맥에서 전기자극 빈도수에 따르는 수축반응이 ET 전처치로 항진되었으나 NPY 전처치로는 차이가 없었다. 전기자극 빈도수에 따른 수축반응은 enalapril투여한 군의 것이 투여하지 않은 군의 것에 비하여 약화되었다. ET투여에 의한 혈중 norepinephrine의 증가작용이 enalapril처치로 감소되었으며, 이러한 감소작용이 뇌척수제거 흰쥐에서 현저하였다. 위의 결과로 미루어 고혈압흰쥐에 enalapril을 장기처치함으로써 고혈압 발현을 효과적으로 억제할 수 있으며, 이는 ET 및 NPY에 의한 승압반응 및 교감신경말단의 신경전달과정의 억제가 관여될 수도 있을 것 같다.

• 대한정형외과학회지
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• 제55권2호
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• pp.117-126
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• 2020

슬관절의 퇴행성 관절염에서 슬관절 전치환술은 널리 시행되고 있고 그 빈도도 점점 증가되고 있다. 수술 후 일상생활로의 복귀, 근력 및 운동범위의 회복 등 기능 회복을 위한 노력이 이루어져야 하고 이는 환자 요인, 수술 술기 및 재활 등 다양한 관점에서 접근해야 한다. 환자의 연령이나 비만의 정도, 성별, 대퇴사두근의 근력 등이 수술 후 기능 회복에 영향을 줄 수 있고 환자의 기대치나 만족도 같은 정신적인 상태도 영향을 준다. 기능 회복을 위하여 수술 전부터 환자교육 및 통증 조절, 대퇴사두근 근력의 강화 같은 치료를 시행할 수 있다. 수술 후 냉찜질 및 압박, 경피적 전기 신경 자극 치료, 신경근육 전기 자극 치료, 저주파 저강도 자기장 치료, 대퇴사두근의 근력운동, 관절범위 운동과 같은 물리치료도 적용할 수 있다. 최근에는 수중에서 근력과 균형감각을 회복시키는 수 치료도 점점 시행되는 추세이다. 이런 기능 회복을 위한 치료들은 수술 후 단기적으로만 시행될게 아니라 장기적으로 꾸준히 시행되는 것이 중요하며 술자는 환자의 상태나, 순응도, 사회적, 심리적 상황 등을 고려하여 적절히 적용하여야 한다.

• 대한전기학회논문지:시스템및제어부문D
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• 제51권1호
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• pp.8-17
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• 2002

This paper suggests that the immune algorithm can effectively be used in tuning of a PID controller. The artificial immune network always has a new parallel decentralized processing mechanism for various situations, since antibodies communicate to each other among different species of antibodies/B-cells through the stimulation and suppression chains among antibodies that form a large-scaled network. In addition to that, the structure of the network is not fixed, but varies continuously. That is, the artificial immune network flexibly self-organizes according to dynamic changes of external environment (meta-dynamics function). However, up to the present time, models based on the conventional crisp approach have been used to describe dynamic model relationship between antibody and antigen. Therefore, there are some problems with a less flexible result to the external behavior. On the other hand, a number of tuning technologies have been considered for the tuning of a PID controller. As a less common method, the fuzzy and neural network or its combined techniques are applied. However, in the case of the latter, yet, it is not applied in the practical field, in the former, a higher experience and technology is required during tuning procedure. In addition to that, tuning performance cannot be guaranteed with regards to a plant with non-linear characteristics or many kinds of disturbances. Along with these, this paper used immune algorithm in order that a PID controller can be more adaptable controlled against the external condition, including moise or disturbance of plant. Parameters P, I, D encoded in antibody randomly are allocated during selection processes to obtain an optimal gain required for plant. The result of study shows the artificial immune can effectively be used to tune, since it can more fit modes or parameters of the PID controller than that of the conventional tuning methods.

• The Korean Journal of Physiology and Pharmacology
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• 제22권5호
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• pp.577-584
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• 2018

Bladder dysfunction is a common complication of diabetes mellitus (DM). However, there have been a few studies evaluating bladder smooth muscle contraction in DM in the presence of pharmacological inhibitors. In the present study, we compared the contractility of bladder smooth muscle from normal rats and DM rats. Furthermore, we utilized pharmacological inhibitors to delineate the mechanisms underlying bladder muscle differences between normal and DM rats. DM was established in 14 days after using a single injection of streptozotocin (65 mg/kg, intraperitoneal) in Sprague-Dawley rats. Bladder smooth muscle contraction was induced electrically using electrical field stimulation consisting of pulse trains at an amplitude of 40 V and pulse duration of 1 ms at frequencies of 2-10 Hz. In this study, the pharmacological inhibitors atropine (muscarinic receptor antagonist), U73122 (phospholipase C inhibitor), DPCPX (adenosine $A_1$ receptor antagonist), udenafil (PDE5 inhibitor), prazosin (${\alpha}_1$-receptor antagonist), verapamil (calcium channel blocker), and chelerythrine (protein kinase C inhibitor) were used to pretreat bladder smooth muscles. It was found that the contractility of bladder smooth muscles from DM rats was lower than that of normal rats. In addition, there were significant differences in percent change of contractility between normal and DM rats following pretreatment with prazosin, udenafil, verapamil, and U73122. In conclusion, we suggest that the decreased bladder muscle contractility in DM rats was a result of perturbations in $PLC/IP_3$-mediated intracellular $Ca^{2+}$ release and PDE5 activity.