• Journal of Physiology & Pathology in Korean Medicine
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• v.19 no.4
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• pp.993-999
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• 2005

This research was peformed to investigate protective effect of Sophora Subprostrata fractions against focal ischemic brain damage after middle cerebral artery(MCA) occlusion using intraluminal suture. Rats were divided into six groups: MCA-occluded group(Control): each administered groups with Sophora Subprostrata total phase(Total), Sophora Subprostrata Aqueous phase (Aqueous), Sophora Subprostrata BuOH phase(BuOH), and Sophora Subprostrata Alkaloid phase(Alkaloid) after MCA-occlusion; sham-operated group(Sham). The right MCA was occluded by A poly-L-lysine coated 4-0 nylon suture thread through the internal carotid artery permanently. Sophora Subprostrata and fractions were administered orally(Smg/ml) for 7 days after MCA-occlusion. The Drain tissue was stained with $2\%$ triphenyl tetrazolium chloride on ischemic brain tissue(2mm section). The results showed that 1) Sophora Subprostrata total phase reduced infarct size and total infarct volume compared to the control group at 24 hours after MCA-occlusion, 2) Sophora Subprostrata Aqueous phase reduced infarct size and total infarct volume compared to the control group at 24 hours after MCA-occlusion, 3) Sophora Subprostrata Alkaloid phase reduced infarct size compared to the control group at 24 hours after MCA-occlusion, but 4) at 7 days after MCA-occlusion, Sophora Subprostrata did not show effective recovery compared with control group. Sophora Subprostrata has protective effects against brain damage at the early stage of focal cerebral ischemia. Sophora Subprostrata total and Aqueous phase produced more pronounced protective effect against focal ischemic brain damage.

• Journal of Korean Neurosurgical Society
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• v.43 no.6
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• pp.281-287
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• 2008

Objective : Cerebral vasospasm still remains a major cause of the morbidity and mortality, despite the developments in treatment of aneurysmal subarachnoid hemorrhage. The authors measured the utility and benefits of external lumbar cerebrospinal fluid (CSF) drainage to prevent the clinical vasospasm and its sequelae after endovascular coiling on aneurysmal subarachnoid hemorrhage in this randomized study. Methods : Between January 2004 and March 2006, 280 patients with aneurysmal subarachnoid hemorrhage were treated at our institution. Among them, 107 patients met our study criteria. The treatment group consisted of 47 patients who underwent lumbar CSF drainage during vasospasm risk period (about for 14 days after SAH), whereas the control group consisted of 60 patients who received the management according to conventional protocol without lumbar CSF drainage. We created our new modified Fisher grade on the basis of initial brain computed tomography (CT) scan at admission. The authors established five outcome criteria as follows : 1) clinical vasospasm; 2) GOS score at 1-month to 6-month follow-up; 3) shunt procedures for hydrocephalus; 4) the duration of stay in the ICU and total hospital stay; 5) mortality rate. Results : The incidence of clinical vasospasm in the lumbar drain group showed 23.4% compared with 63.3% of individuals in the control group. Moreover, the risk of death in the lumbar drain group showed 2.1 % compared with 15% of individuals in the control group. Within individual modified Fisher grade, there were similar favorable results. Also, lumbar drain group had twice more patients than the control group in good GOS score of 5. However, there were no statistical significances in mean hospital stay and shunt procedures between the two groups. IVH was an important factor for delayed hydrocephalus regardless of lumbar drain. Conclusion : Lumbar CSF drainage remains to playa prominent role to prevent clinical vasospasm and its sequelae after endovascular coiling on aneurysmal subarachnoid hemorrhage. Also, this technique shows favorable effects on numerous neurological outcomes and prognosis. The results of this study warrant clinical trials after endovascular treatment in patients with aneurysmal SAH.

• Journal of Korean Neurosurgical Society
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• v.49 no.5
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• pp.296-298
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• 2011

Spinal intradural cysticercosis is a rare manifestation of neurocysticercosis. We report a unique patient who showed visual symptoms and normal imaging of the brain caused by isolated spinal neurocysticercosis. A 59-year-old male patient was admitted to the emergency unit with a history of severe headache and progressive blurred vision. Brain computed tomographic scanning and magnetic resonance imaging showed normal cerebral anatomy without hydrocephalus. The fundoscopic evaluation by an ophthalmologist showed bilateral papilledema. Perimetry studies revealed visual field defects in both eyes. With the diagnosis of pseudotumor cerebri, a lumbar tap was attempted; however, we could not drain the cerebrospinal fluid in spite of appropriate attempts. Lumbar magnetic resonance imaging revealed multilevel intraspinal lesions that were confirmed histologically to be neurocysticercosis. An intraoperative lumbar puncture revealed an increased opening pressure and cytochemical analysis showed elevated cerebrospinal fluid protein level. The headache resolved immediately after surgery. However, the visual symptoms remained and recovered only marginally despite antihelminthic medications after six months of operation.

• The Korean Journal of Pain
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• v.20 no.2
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• pp.235-239
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• 2007

Spontaneous intracranial hypotension (SIH) is believed to be a benign disease. However, numerous studies have reported serious complications related to SIH, including subdural hematoma. In this case report, a 54-year-old male patient visited the emergency room with orthostatic headache. A brain magnetic resonance imaging (MRI) study showed diffuse mild thickening and enhancement of pachymeninges, with a suspicious minimal amount of subdural fluid collected in the left posterior parietal area. His orthostatic headache showed no improvement with conservative treatment; but his pain was almost completely relieved after two trials of cervical epidural blood patch. On the 74th day after the onset of his pain, the patient showed a drowsy mental status and slurred speech when he visited the pain clinic. Brain computerized tomography indicated a left subdural hemorrhage, and he underwent emergency operation to drain the SDH. In conclusion, pain clinicians should pay attention to abrupt changes in mental status as well as continuous headache, for the early diagnosis of SDH in SIH patients.

• International Commerce and Information Review
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• v.8 no.3
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• pp.3-21
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• 2006

This study aims to explore the developing strategies of knowledge based industry in ChunChon Area. This study suggests several strategies for promoting local development in Chunchon Area as follows ; first, building of local innovation system in chunchon area and convergence and diffusion of knowledge based industries. second, making of industrial environment suitable to developing knowledge based industries. third, the establishment of overall industrial supporting systems. fourth, expansion of industrial infra and prevention of the brain drain. fifth, transformation of industrial complex into innovation clusters. The result of this study will be useful for the chief executives officers to make more rational decision making for industrial developing strategies is related to the Knowledge based Industries. The paper also strives to provoke debate in this area with to encouraging further research on the topic.

• East Asian Economic Review
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• v.23 no.1
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• pp.3-26
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• 2019

This study investigates the effect of high-skilled inventor emigration rate on growth rate of the country of origin (COO). Inventor emigrants represent the human capital that can generate highly innovative work. The social network they form spurs knowledge diffusion and technology transfer back to their COOs, which in turn affects innovation and growth in their home countries. We run dynamic panel estimation for 154 countries during 1990-2011, and empirically show that a positive and statistically significant effect exists for the interaction of inventor emigration and trade. The result indicates that the direct negative impact of the brain drain can be mitigated by the positive feedback effect generated by the high-skilled inventor emigrants abroad. When coupled with an active trade policy that reinforces growth, countries can partially recoup the direct effect of the human capital loss. We stress the importance of international trade for successful technology transfer to occur, and offer insights for policies that can utilize the benefits of the rich social network of their high-skilled emigrants.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.35 no.11
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• pp.1127-1131
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• 2011

We report on a pumpless cell culture chip in which a constant medium perfusion rate is maintained by balanced droplet dispensing. Previous chips had a decreasing perfusion rate due to the decreasing hydraulic-head difference ${\Delta}h$ between the inlet and drain. However, the present chip maintains a constant medium perfusion rate due to the constant ${\Delta}h$ between the inlet and drain maintained by balanced droplet dispensing. The perfusion rate Q was measured to be 0.1-$0.3{\mu}l$/min with a maximum deviation and error of 9.96% and 6.92%, respectively. In the perfusion culture (Q = 0.1-$0.3{\mu}l$/min), the maximum growth-rate of H358 cells was measured to be $57.8%{\pm}21.1%$ per day, which is 1.9 times higher than that of a static culture. The perfusion culture also resulted in higher cell viability than a static culture. The present chip offers a favorable environment with a high growth-rate and viability and thus has potential for use in the integrated cell culture system.

• The Journal of Korean Physical Therapy
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• v.25 no.3
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• pp.126-131
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• 2013

This case report described a single case of adult stoke patient due to Moyamoya disease through long-term follow-up observation, which included his demographics, brain images, and change of motor function and functional activities. The subject was the 54-year-old male diagnosed with left hemiparesis from a stroke due to multifocal encephalomalacia in both hemispheres. At the time of the stroke attack, he took brain surgery intervention including external ventricular drain. Physical and occupational therapy for stroke rehabilitation were admitted including muscle strengthening exercises, functional activity/ADL training, neurofacilitative techniques with bobath or proprioceptive neuromuscular facilitation concepts, and compensatory strategy. Patient's MRI showed that right frontal lobe, right peri-ventricular area, left parietal, and left occipital lobes were damaged, and MRA showed that abnormal collateral vessel was richly developed in both hemispheres by occlusion of proximal internal carotid arteries in both sides. His motor strength was improved from poor to good grade in all of upper and lower limb motions, that MBC was improved from stage 1 to stage 5. In FAC and barthel index, at the initial evaluation, he could not perform any functional movement, but his FAC and barthel index were on 3 and 14 points at present, respectively. During long-term follow-up for approximately 4 years, the subject's functional motor ability was improved, as similar with recovery progression of usual stroke patient. We believe that this single case report will provide clinical information and concern regarding Moyamoya disease with physical therapist, in terms of such as epidemiology, pathogenesis, diagnostic procedures, clinical features, recovery process, and prognosis.

• STI Policy Review
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• v.9 no.1
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• pp.99-132
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• 2018

Developing countries face numerous challenges in the process of building science, technology, and research capacity; in particular, the formation and accumulation of skilled S&T workforce. The lack of organized and sustainable higher education options (Master and Doctoral programs), nonexistent or low-quality academic programs, and the absence of research-oriented study options are some of the strong contributors for talented students to emigrate to developed countries. At the same time, the consolidation of a global knowledge economy, the internationalization of higher education, and the competition to attract foreign talent in industrialized countries present challenges for underdeveloped nations to retain their already scarce skilled human resources. In this context, student mobility has been used as a policy mechanism to cope with S&T workforce shortages in S&T laggard nations. It has also enabled opportunities for international cooperation to play a key role. While significant literature has been devoted to studying the gains of developed nations with the arrival and potential migration of the mobilized students, few scholarly inquiries have addressed the benefits and losses experienced by their countries of origin. More importantly, limited research can be found on policy options and policy implications for developing countries to deal with the dilemmas presented by the brain-drain/brain-circulation debate. The goal of this article is to study empirical evidence of an international cooperation initiative for student mobility between the Republic of Korea and Guatemala (implemented during 2009-2015). The paper analyzes this particular international cooperation experience from the perspective of the different actors involved and attempts to draw policy implications and policy options for developing countries to deal with potential risks and gains derived from international mobility for their S&T capacity building.

• East Asian Economic Review
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• v.20 no.2
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• pp.229-275
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• 2016

We study the effect of the high-skilled emigration rate on the growth rate of the source countries. We incorporate the foreign direct investment and the policy variables into the panel model and also their interactions with the high-skilled emigration rate, as they are related to the network externality that may be created by the high-skilled emigrants working abroad. We apply the static fixed-effects model and compare it with the results obtained in the dynamic panel model with system generalized methods of moments estimators. We find the negative effect of the high-skilled emigration rate by itself and in its interaction with the foreign direct investment only in the dynamic model. However, we find positive coefficient for the interaction of the high-skilled emigration rate and the civil liberties index, which holds across the static and dynamic specifications. This implies that the effect of the high-skilled emigration rate on the growth rate of the source countries can be positive, and the extent is larger for countries with 'poor' civil liberties. The developing countries with low levels of foreign direct investment inflows and 'poor' civil liberties can best benefit from the high levels of skilled emigration outward. Through finding significant interactions with other variables, we confirm that the high-skilled emigration should be considered along with other related variables in measuring its impact on growth. The implications offer suggestions for the international trade and aid policies.