• The Korean Journal of Physiology and Pharmacology
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• 제1권6호
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• pp.625-637
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• 1997

Calcium ions are implicated in a variety of physiological functions, including enzyme activity, membrane excitability, neurotransmitter release, and synaptic transmission, etc. Calcium antagonists have been known to be effective for the treatment of exertional angina and essential hypertension. Selective and nonselective voltage-dependent calcium channel blockers also have inhibitory action on the acute and tonic pain behaviors resulting from thermal stimulation, subcutaneous formalin injection and nerve injury. This study was undertaken to investigate the effects of iontophoretically applied $Ca^{++}$ and its antagonists on the responses of WDR (wide dynamic range) cells to sensory inputs. The responses of WDR cells to graded electrical stimulation of the afferent nerve and also to thermal stimulation of the receptive field were recorded before and after iontophoretical application of $Ca^{++}$, EGTA, $Mn^{++}$, verapamil, ${\omega}-conotoxin$ GVIA, ${\omega}-conotoxin$ MVIIC and ${\omega}-agatoxin$ IVA. Also studied were the effects of a few calcium antagonists on the C-fiber responses of WDR cells sensitized by subcutaneous injection of mustard oil (10%). Calcium ions and calcium channel antagonists ($Mn^{++}$, verapamil, ${\omega}-conotoxin$ GVIA & ${\omega}-agatoxin$ IVA) current-dependently suppressed the C-fiber responses of WDR cells without any significant effects on the A-fiber responses. But ${\omega}-conotoxin$ MVIIC did not have any inhibitory actions on the responses of WDR cell to A-fiber, C-fiber and thermal stimulation. Iontophoretically applied EGTA augmented the WDR cell responses to C-fiber and thermal stimulations while spinal application of EGTA for about $20{\sim}30\;min$ strongly inhibited the C-fiber responses. The augmenting and the inhibitory actions of EGTA were blocked by calcium ions. The WDR cell responses to thermal stimulation of the receptive field were reduced by iontophoretical application of $Ca^{++}$, verapamil, ${\omega}-agatoxin$ IVA, and ${\omega}-conotoxin$ GVIA but not by ${\omega}-conotoxin$ MVIIC. The responses of WDR cells to C-fiber stimulation were augmented after subcutaneous injection of mustard oil (10%, 0.15 ml) into the receptive field and these sensitized C-fiber responses were strongly suppressed by iontophoretically applied $Ca^{++}$, verapamil, ${\omega}-conotoxin$ GVIA and ${\omega}-agatoxin$ IVA. These experimental findings suggest that in the rat spinal cord, L-, N-, and P-type, but not Q-type, voltage-sensitive calcium channels are implicated in the calcium antagonist-induced inhibition of the normal and the sensitized responses of WDR cells to C-fiber and thermal stimulation, and that the suppressive effect of calcium and augmenting action of EGTA on WDR cell responses are due to changes in excitability of the cell.

• Journal of Acupuncture Research
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• 제23권5호
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• pp.23-29
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• 2006

Objectives : The present study was conducted to evaluate the effects of automatically controlled rotating acupuncture (ACRA) on thermal allodynia in neuropathic pain rats, and to examine whether the endogenous opioid system mediates the effects of ACRA. Methods : For the neuropathic surgery, the right superior caudal trunk was resected at the level between S1 and S2 spinal nerves innervating the tail. Two weeks after the nerve injury, ACRA stimulation with 4 different stimulation conditions (i.e., angle and frequency of rotation: 90o+1Hz, 90o+1/4Hz, 360o+/1Hz, and 360o+1/4Hz) was delivered to the Zusanli (ST36) acupoint for 15 min. The behavioral signs of thermal allodynia were evaluated by the tail immersion test (i.e., immersing the tail in cold $(4^{\circ}C)$ or warm $(4^{\circ}C)$ water and measuring the latency to an abrupt tail movement) before and after the stimulation. In an additional set of experiments, we examined the effects of naloxone (opioid Results : ACRA stimulations under all of the conditions above significantly relieved thermal antagonist, 2mg/kg, i.p.) on the action of ACRA stimulation. allodynia. There is no difference in the anti-allodynic effects among the 4 stimulation conditions. In addition, the effect of ACRA on thermal allodynia was reversed by naloxone pretreatment. Conclusion : These results indicate that ACRA stimulations have relieving effects on thermal allodynia in neuropathic pain rats, irrespective of stimulation parameters, and that this is mediated by the endogenous opioid system.

• 대한약리학회지
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• 제31권3호
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• pp.323-331
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• 1995

사구체내 단핵구의 침윤은 면역학적뿐 아니라 비면역학적 사구체 질환 발생 초기에 특징적으로 관찰된다. 단핵구에서 합성되는 대표적인 사이토 카인인 tumor necrosis factor $(TNF){\alpha}$의 합성이 각종 사구체 질환과 관련되어 증가할 뿐 아니라 외부에서 투여한 $TNF{\alpha}$는 사구체 질환의 발생과 진행에 수반된 유사한 증세를 초래한다. 따라서 본 연구에서는 사구체 질환의 표적세포인 혈관간 세포를 이용하여 $TNF{\alpha}$에 의한 세포독성 기전을 검색하고자 하였다. 표준화된 체걸름법을 이용하여 사구체를 분리한후 collagenase로 처리하여 배양하므로써 혈관간 세포의 특징을 지닌 일차 배양 혈관간 세포계를 수립하였다. 세포독성의 지표로서 지질과산화물을 측정했을때, $TNF{\alpha}$는 용량의존적으로 배양 혈관간 세포의 지질과산화를 증가시켰다. 배양혈관간 세포를 $45^{\circ}C$에서 30분간 처리했을 때 heat shock protein 70의 합성이 증가함을 western 분석으로 확인하였을 뿐 아니라, $TNF{\alpha}$에 의한 지질과산화 증가를 효과적으로 억제함을 관찰하였다. 이상의 결과는 $TNF{\alpha}$에 의한 지질과산화 증가가 사구체 질환의 발생이나 진행에 관하여할 수 있음과 고온 전처리에 의해서 heat shock 반응을 초래하므로써 $TNF{\alpha}$에 의한 사구체 손상을 보호할 수 있음을 시사하였다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제37권5호
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• pp.355-364
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• 2011

Introduction: This study evaluated nerve recovery through retrospective study of patients with lingual nerve damage. Patients and Methods: The patients who visited Seoul National University Dental Hospital for an injury to the lingual nerve from April 1988 to August 2009 were enrolled in this study (n=41). The relevance of various factors including the causes of damage, age, etc. was analyzed by the subjective improvement based upon questionnaires and the clinical records. The evaluation variants were a subjective assessment and neurosensory examination composed of the direction, contact threshold, two-point discrimination, pin prick, thermal discrimination and current perception threshold. Results: The causes of lingual nerve damage were an extraction of the lower third molar (75.6%), local anesthesia (9.7%), incision and drainage (4.88%), trauma (2.44%). The evaluation of subjective prognosis exhibited no difference in sensory improvement depending on the cause, age and gender. Based upon the subjective evaluation, 44.7% of patients showed sensory improvement. The first hospital visit from injury was shorter in the group showing subjective improvement (3.41 months) than those showing no improvement (5.24 months) (P=0.301). Thirty six out of 41 patients were treated with only conservative therapy and 5 patients were treated by surgical intervention. Neurosensory examinations revealed improvement, although not statistically significant, and the degree was higher in the subjectively improved group. The contact threshold discrimination showed the highest correlation with subjective improvement (P=0.069). Most of the sensory recovery was gained within 12 months and the degree of improvement at the tip of the tongue was higher than that of the dorsum (P<0.001). Conclusion: The damaged lingual nerve improved at a rate of 44.7% and mostly within 12 months after the incident. There was no difference between the subjective prognosis and neurosensory examination depending on the cause of damage, age and gender, whereas the contact threshold discrimination was the best variant that reflected the subjective prognosis statistically.

• 한국안전학회지
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• 제28권6호
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• pp.42-48
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• 2013

Forensic engineering is the application of engineering principles covering the investigation of constructed facilities and systems that fail to perform as intended, causing personal injury or damage to property, environmental, economy etc. In the year 2012, two collapsed accidents of the large scaffolding system in national thermal power station occurred one after another, causing many casualties. In this study, we had performed to investigate the collapsed accident of scaffolding system occurred in the a thermal power station of two accidents. First, the investigation about the collapsed accidents site had performed to understand collapsed state and structures of the scaffolding system. Second, reviewing the materials concerning about the applied weight on the scaffolding system had performed. The applied weight is sum of the weights of the 15 workers, additional materials for coating work and dispersed and loaded shot ball on the foothold etc. the applied weight that calculated exceed more three times than the safe working load. Third, we had confirmed the install state of the materials of the scaffolding system by reviewing the quantity of the materials on the manual and the real system. Last, structural analysis had performed to evaluate structural integrity of the scaffolding system using Ansys. Through a series of this processes, the definite accidents causes of the collapsed scaffolding system revealed. Through these studies, the collapse accident that may occur in the scaffolding system in thermal power station can be minimized by performing specialized and systematic investigation on the accidents in terms of Forensic engineering.

• The Journal of Korean Physical Therapy
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• 제21권3호
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• pp.95-102
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• 2009

Purpose: This study evaluates MCP-1 expression in the dorsal horn of a rat model of lumbar disc herniation by an autograft of the nucleus pulposus to the spinal nerve. Methods: After a coccygeal nucleus pulposus graft to the left $5^{th}$ lumbar spinal nerve, proximal to dorsal root ganglion, mechanical allodynia and thermal hyperalgesia were assessed 1 day before surgery, and 1, 10, 20, 30 days after surgery. The mRNA of MCP-1 in the dorsal horn was assessed by real time PCR to compare the temporal pattern of neuropathic pain of the lumbar disc herniation model. Results: In the ipsilateral side of the lumbar disc herniation models, mechanical allodynia and thermal hyperalgesia reached a maximum at 10 days after surgery with significant difference from the control group. Pain was also provoked in the contralateral side of the lumbar disc herniation models with less intensity than the ipsilateral side. The level of MCP-1 mRNA expression in the dorsal horn reached a peak at 20 days after surgery. Conclusion: Mechanical allodynia and thermal hyperalgesia was induced by nucleus pulposus in a rat lumbar disc herniation model, similar to a previously reported peripheral nerve injury model. The level of MCP-1 expression was higher in the dorsal horn of the ipsilateral and contralateral sides. These results suggest that MCP-1 might play a role in the maintenance of neuropathic pain.

• 정신신체의학
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• 제3권1호
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• pp.91-97
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• 1995

Pain is a complex symptom consisting of a sensation underlying potenial disease and associated emotional state. Acute pain is a reflex biological response to injury, in contrast, chronic pain consists of pain of a mininum of 6 months duration and associates with physical, emotional past experience, economic resources of the patient, family and society. Moreover, chronic pain is characterized by physiological affective and behavioral responses that are quite different than those of acute pain. The different type of stimuli exciting pain receptor are mechanical, thermal and chemical stimli and chronic pain are concerned with three of all stimli. The major three components of pain central(Analgesia) system in the brain and spinal cord are 'periaqueductal gray area of the mesencephalon', 'the raphe magnus nucleus' and 'pain inhibitory complex located in the dorsal horns of the spinal cord'. But unfortunately, the central biochemical mechanisms of chronic pain are not clearly defined. To proper management of chronic pain, comprehensive urderstanding as a psychosomatic aspect and multidisciplinary therapeuti-team approach must be emphasized.

• 대한물리치료과학회지
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• 제8권2호
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• pp.1091-1097
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• 2001

The main experiments was investigated the skin tissue damage changing for the skin bum having influence on the skin and the liver and also observed the radical liver weight, ALT in the serum, the fluctuating of AST for the skin bum causing to the liver damage. Anatomically the edema formation of skin after thermal injury was showed, and skin bum increased liver weight (% of body weight, p<0.05) and the activity of serum aniline aminotrasferase (p<0.05), and also histologically induced wes of epidermal layer, protein degeneration of connective tissue, local hemorrhage and degeneration of glandular epithelium in the skin tissue. Liver tissue showed the evidences of postbum damage, they were sinusoidal dilatation, cell swelling, infiltration of inflammatory cells.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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• pp.170.2-170.2
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• 2003

The most common cause of death in fires is the inhalation of noxious gases rather than thermal injury. Carbon monoxide is well-known toxic component in fire atmospheres. However, the importance of hydrogen cyanide(HCN) as a toxic agent in the fire related fatalities(FRF) is under discussion. HCN is known to be produced in fires involving by the pyrolysis of polyacrylonitril (PAN) and other nitrogen-containing polymer. (omitted)

• International Journal of Oral Biology
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• 제34권3호
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• pp.157-164
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• 2009

We recently described a novel animal model of trigeminal neuropathic pain following compression of the trigeminal ganglion (Ahn et al., 2009). In our present study, we adapted this model using male Sprague-Dawley rats weighing between 250-260 g and then analyzed the behavioral responses of these animals following modified chronic compression of the trigeminal ganglion. Under anesthesia, the rats were mounted onto a stereotaxic frame and a 4% agar solution ($10{\mu}L$) was injected in each case on the dorsal surface of the trigeminal ganglion to achieve compression without causing injury. In the control group, the rats received a sham operation without agar injection. Air-puff, acetone, and heat tests were performed at 3 days before and at 3, 7, 10, 14, 17, 21, 24, 30, 40, 55, and 70 days after surgery. Compression of the trigeminal ganglion produced nociceptive behavior in the trigeminal territory. Mechanical allodynia was established within 3 days and recovered to preoperative levels at approximately 60 days following compression. Mechanical hyperalgesia was also observed at 7 days after compression and persisted until the postoperative day 40. Cold hypersensitivity was established within 3 days after compression and lasted beyond postoperative day 55. In contrast, compression of the trigeminal ganglion did not produce any significant thermal hypersensitivity when compared with the sham operated group. These findings suggest that compression of the trigeminal ganglion without any injury produces prolonged nociceptive behavior and that our rat model is a useful system for further analysis of trigeminal neuralgia.