• The Transactions of the Korean Institute of Electrical Engineers C
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• v.48 no.2
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• pp.109-116
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• 1999

ZnO Varistor is an electronic ceramic device to absorb the surge voltage from low voltage to high. To investigate the puncture mechanism occurring in NnO varistor, the Voronoi simulation for formulating the relation between the applied voltage and the increase of the temperature inside grain is applied. The Voronoi network can realize the structure of the practical varistor better than the established simple network. Using the current through each grain and the voltage applied to the grain, Joule heating energy is calculated and the phenomenon that the puncture occurs can be analyzed quantitatively by simulating the electric and thermal characteristics according to the externally applied pulsed voltage.

• Journal of Korean Neurosurgical Society
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• v.51 no.2
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• pp.102-104
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• 2012

Although decompressive craniectomy is an effective treatment for various situations of increased intracranial pressure, it may be accompanied by several complications. Paradoxical herniation is known as a rare complication of lumbar puncture in patients with decompressive craniectomy. A 38-year-old man underwent decompressive craniectomy for severe brain swelling. He remained neurologically stable for five weeks, but then showed mental deterioration right after a lumbar puncture which was performed to rule out meningitis. A brain computed tomographic scan revealed a marked midline shift. The patient responded to the Trendelenburg position and intravenous fluids, and he achieved full neurologic recovery after successive cranioplasty. The authors discuss the possible mechanism of this rare case with a review of the literature.

• Proceedings of the KIEE Conference
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• 1998.07d
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• pp.1282-1284
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• 1998

ZnO Varistor is an electronic ceramic device for controlling the surge voltage from low level to high. In this study, the puncture mechanism occurring in ZnO varistor is investigated, and the simulation for restraining the puncture by formulating the relation between the applied voltage and the increase of the inside temperature of grain is applied. In order to simulate the cause of the current localization which is the primary factor causing the puncture, the localization phenomenon and the temperature distribution induced by the localized current, the Voronoi network is applied, which can realize the structure of the practical varistor better than the established simple network. Using the current through each grain and the voltage applied to the grain boundary obtained from that simulation, the Joule heating energy is calculated and the phenomenon that the puncture occurs can be analyzed quantitatively by simulating the electric and thermal characteristics according to the externally applied pulsed voltage.

• The Korean Journal of Pain
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• v.30 no.2
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• pp.93-97
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• 2017

The sphenopalatine ganglion (SPG) is a parasympathetic ganglion, located in the pterygopalatine fossa. The SPG block has been used for a long time for treating headaches of varying etiologies. For anesthesiologists, treating postdural puncture headaches (PDPH) has always been challenging. The epidural block patch (EBP) was the only option until researchers explored the role of the SPG block as a relatively simple and effective way to treat PDPH. Also, since the existing evidence proving the efficacy of the SPG block in PDPH is scarce, the block cannot be offered to all patients. EBP can be still considered if an SPG block is not able to alleviate pain due to PDPH.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.229-229
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• 2002

Although hepatocellular dysfunction occurs during sepsis. the mechanism responsible for this remains unclear. Since Kupffer cells provide signals that regulate hepatic response in endotoxin and inflammation. the aim of this study was to investigate the role of Kupffer cells in the alterations in the hepatic microsomal drug metabolizing function during sepsis. Rats were subjected to polymicrobial sepsis by cecal ligation and puncture (CLP)followed by fluid resuscitation. (omitted)

• Journal of Biomedical Engineering Research
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• v.23 no.4
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• pp.323-327
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• 2002

Chronic diabetic patients need to sample capillary blood for monitoring and controlling the blood sugar level. Frequent sampling requires to minimize pain during skin puncture. The present study developed mechanisms to minimize pain with effective sampling procedure. which consisted of tapered spring, guiding tunnel, and 30G needle Penetration depth was limited to within 2mm for pain reduction as well as for safety. Simple no-reuse mechanism also prevented the cross-patient and secondary infection possibility. Clinical experiments demonstrated the best convenience and safety with minimal pain in the diabetes, normal, and nursing students groups. Sing1e blood sampling was enough for successful blood sugar test by portable analyzer. The present sing1e use auto-lancet should be of great convenience in frequent capillary blood sampling for the diabetes.

• The Korean Journal of Pain
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• v.10 no.1
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• pp.104-108
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• 1997

Spontaneous intracranial hypotension, a syndrome of low CSF pressure, occurs without preceding events such as lumbar puncture, back trauma, operative procedure or medical illness. The most characteristic symptom is an occipital or frontal headache which is aggrevated in the erect position and relieved in the supine position. This syndrome usually resolves spontaneously or with strict bed rest. When the headach persists or is incapacitating, more aggressive treatment may be necessary. Autologous epidural blood patch is highly effective in the management of spontaneous intracranial hypotension. Epidural blood produces an organized clot which effectively tamponade any dural CSF leak. The rapid relief of headache immediately after the infusion of blood occur by some other mechanism, such as an increase in subarachnoid pressure that is known to occur with infusion of fluid into the lumbar epidural space. We report three cases of spontaneous intracranial hypotension successfully treated with epidural blood patch.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.301.3-302
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• 2002

Sepsis remains the leading cause of morbidity and mortality following trauma. Although hepatocellular dysfunction occurs during trauma and sepsis. the mechanism responsible for this remains unclear. We investigated the role of Kupffer cells in the alterations in microsomal drug metabolizing function during trauma and sepsis. Rats were subjected to trauma by femur fracture (FFx). After 72h, polymicrobial sepsis was induced by cecal ligation and puncture(CLP). (omitted)

• Journal of Acupuncture Research
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• v.27 no.4
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• pp.9-18
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• 2010

Objectives : This study will broaden understanding of acupotomy therapy through comparison of side effects and complication which can be caused by the mechanism of treatment, surgical methods, and procedure by acupotomy therapy and epidural neuroplasty. Moreover, through an in-depth analysis of headache affected by two procedures, this research is supposed to find prospective cures for headache after acupotomy therapy. Methods : To compare acupotomy therapy with epidural neuroplasty this research was done using a comparative analysis eight theses about acupotomy therapy since 1995, as well as eleven theses about epidural neuroplasty since 2000. Other theses and data were used as references in the process of comparative analysis. Results : Acupotomy therapy and epidural neuroplasty, new treatments of damaged discs in the spine and stenosis made in 1990s, have the mechanism of treatment in common in that adhesion, a node or scar caused by the soft tissue damage is removed by putting catheter or acupuncture into the lesions. Epidural neuroplasty has additional injection into the lesions, which is different from acupotomy therapy in the process of surgical procedure. There are various reports of positive effects about curative effect in these two treatments. The two procedures may cause various complications. Headache may be a complication after surgery. The headache after acupotomy therapy is characterized as being an ache in the body, which is similar to that of post-dural puncture headache in the outbreaks and symptom. Headache after percutaneous epidural neuroplasty appears in general, which is similar to a headache as a result of the increased pressure of the brain spinal cord regardless of posture. Conclusions : Although they are alike in the mechanism of treatment, surgical methods and side effects, and complication after they are carried out as a result of analyzing theses related to acupotomy therapy and percutaneous epidural neuroplasty, there is a difference in aspects and mechanism of headaches experienced after the procedure.

• The Korean Journal of Physiology and Pharmacology
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• v.1 no.6
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• pp.647-655
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• 1997

The purpose of present study is to investigate the influence of a spinal gamma-aminobutyric acid B($GABA_B$) receptor on a central regulation of blood pressure(BP) and heart rate(HR), and to define its mechanism in the spinal cord. In urethane-anesthetized, d-tubocurarine-paralyzed and artificially ventilated male Sprague-Dawley rats, intrathecal administration of drugs were carried out using injection cannula(33-gauge stainless steel) through the guide cannula(PE 10) which was inserted intrathecally at lower thoracic level through the puncture of a atlantooccipital membrane. Intrathecal injection of an $GABA_B$ receptor agonist, baclofen(30, 60, 100 nmol) decreased both BP and HR dose-dependently. Pretreatment with 8-bromo-cAMP(50 nmol), a cAMP analog, or glipizide(50 nmol), a ATP-sensitive $K^+$ channel blocker, attenuated the depressor and bradycardic effects of baclofen(100 nmol), but not with 8-bromo-cGMP(50 nmol), a cGMP analog. These results suggest that the $GABA_B$ receptor in the spinal cord plays an inhibitory role in central cardiovascular regulation and that this depressor and bradycardic actions are mediated by the decrease of cAMP via the inhibition of adenylate cyclase and the opening of $K^+$ channel.