• Biomolecules & Therapeutics
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• 제8권2호
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• pp.160-166
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• 2000

The present study examined influence of various ischemic duration on extent of focal ischemic brain injury induced by middle cerebral artery occlusion (MCAO) in rats. The MCAO was produced by insertion of a 17 mm silicone-coated 4-0 nylon surgical thread to the origin of MCA through the internal carotid artery for 30, 60, 90, 120 min (transient) or 24 hr (permanent) in male Sprague-Dawley rats under isoflurane anesthesia. Reperfusion in transient MCAO models was achieved by pulling the thread out of the internal carotid artery. Only rats showing neurological deficits characterized by left hemiparesis and/or circling to the left, were included in cerebral ischemic groups. The rats were sacrificed 24 hr after MCAO and seven serial coronal slices of the brain were stained with 2,3,5-triphenyltetrazolium chloride. Infarct size was measured using a computerized image analyzer. Ischemic damage was common in the frontoparietal cortex (somatosensory area) and the lateral segment of the striatum while damage to the medial segment of the striatum depended on the duration of the occlusion. In the 30-min MCAO grouts, however, infarcted region was primarily confined to the striatum and it was difficult to clearly delineate the region since there was mixed population of live and dead cells in the nucleus. Infarct volume was generally increased depending on the duration of MCAO, showing the most severe damage in the permanent MCAO group. However, there was no significant difference in infarct size between the 90-min and 120-min MCAO groups. % Edema also tended to increase depending on the duration of MCAO. The results suggest that the various focal ischemic rat models established in the present study can be used to evaluate in vivo neuroprotective activities of candidate compounds or to elucidate pathophysiological mechanisms of ischemic neuronal cell death.

• Journal of Chest Surgery
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• 제25권12호
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• pp.1508-1515
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• 1992

Between 1975 and 1992, forty five patients with trachea stenosis received tracheoplasty for relief of obstruction. The causes of airway problem are brain contusion[19 cases, 40%], cerebrovascular disease[3 cases, 7%], drug intoxication[8 cases, 18%], psychotic problem[2 cases, 4%], trachea tumor[3 cases, 7%], adult respiratory distress syndrome[9 cases, 20%] and direct trauma[1 case, 2%]. Direct causes of trachea stenosis were complications of tracheostomy[36 cases, 80%], complications of nasotracheal intubation[5 cases, 11%], tumor[3 cases, 6%] and trauma[1 case, 2%]. Thirty one patients underwent the sleeve resection and end-to-end anastomosis. Five patients performed a wedge resection and end-to-end anastomosis. Forteen patients received the Montgomery T-tube for relief of airway obstruction. Four patients have done simple excision of granulation tissue. Two, subglottic stenosis patients were received Rethi procedure[anterior division of cricoid cartilage, wedge partial resection of lower thyroid cartilage and Montgomery T-tube molding] and the other subglottic stenosis patient underwent permanent trachea fenestration. Including cervical flexion in all patients postoperatively, additional surgical techniques for obtain tension-free anastomosis were hyoid bone release technique in two cases, and hilar mobilization, division of inferior pulmonary ligament and mobilization of pulmonary vessel at the pericardium were performed in one case. Cervical approach was used in 39 cases, cervicomediastinal in 12 cases and transthoracic in one case. Complications of tracheoplasty were formation of granulation tissue at the anastomosis site[3 cases], restenosis[9 cases], trachea-innominate artery fistula[2 cases], wound infection[2 cases], separation of anastomosis[2 cases], air leakage[3 cases], injury to a recurrent laryngeal nerve[temporary 8 cases, permanent 2 cases] and hypoxemia[1 case]. Surgical mortality for resection with primary reconstruction was 6.7%, with one death due to postoperative respiratory failure and two deaths due to tracheo-innominate artery fistula.

• Journal of Chest Surgery
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• 제18권2호
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• pp.165-173
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• 1985

A clinical analysis was performed n 706 uses of patent ductus arteriosus experienced at Department of Thoracic and Cardiovascular Surgery, Seoul National University Hospital during 27 years period from 1958 to 1984. Of the 706 patients of PDA, 244 patients were male and 462 patients were female and ages ranged from 2 months to 53 years old with the average age of 8.5 years. The chief complaints on admission were dyspnea on exertion and frequent URI in 58.9%, non specific symptoms such as palpitation and easy fatigability in 9.7%, symptoms of CHF in 2.0% and no subjective symptoms in 29.4%. On auscultation of heart, continuous machinery murmurs were heard in 82% and only systolic murmurs were heard in 18% of patients. On simple chest PA of patients, cardiomegalies were detected in 78% and there were increased pulmonary vascularities in 93% of patients. EKG findings were as followed; LVH 56.9%, BVH 12.6%, RVH 2.9% and WNL 27.6%. Cardiac Catheterizations were performed in 512 patients and mean Qp/Qs was 2.56 and mean systolic pulmonary artery pressure was 45mmHg. Operation methods were as followed; in patients in whom operations were performed on PDA only, ligation 94.3%, division 3.7% and ligation [0.5%] or trans-pulmonary artery suture closure [1.5%] under cardiopulmonary bypass 2.0% and in patients in whom operations were performed with associated anomalies, ligation 17.6%, division 2.4%, and ligation [44.7%] or trans-pulmonary artery suture closure [35.3%] under cardiopulmonary bypass 80%. 52 postoperative complications [8.4%] were developed in 42 patients [6.8%] and its were as followed; permanent or transient hoarseness 16 [2.6%], intraoperative rupture of PDA 8 [1.3%], recannalization 6 [1.[%], operative death 5 [0.8%], late death 4 [0.6%] and other miscellaneous complications 13 [2.1%]. 140 associated cardiac anomalies [19.8%] were found in 105 patients [14.9%] and its were as followed; VSD 68 [9.6%], COA 15 [2.1%], Subaortic discrete membrane 7 [0.9%], ASD 6 [0.8%], TOF 5 [0.7%] and other miscellaneous and

• Journal of Chest Surgery
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• 제11권3호
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• pp.326-332
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• 1978

There appears some conduction defects frequently after total correction of Tetralogy of Fallot. Common defect is right bundle branch block due to surgical intervention. We experienced complete A-V block which occured 3 months later after total correction of Tetralogy of Fallot in a 8 year old boy. The patient was completely free of any A-V block after the operation for 3 months, and sudden onset of A-V block with coupled premature ventricular contractions resulted him in shock state during the attack of severe bronchopneumonia for 4 days prior to the second visit. Emergency implantation of Cordis demand type temporary pacemaker was necessary to control the complete heart block with bradyarrhythmia and frequent ventricular fibrillation. Permanent cardiac pacemaker was implanted two weeks later as indicated with Cordis Stanicor lambda demand pacemaker, and the patient was discharged uneventfully on the 8th post implantation day with the heart rate of 72/min. Another 3 months after the implantation, the patient was transported to this hospital as dead on arrival after an accidental fall from a 2 meter height, and all possible cardiopulmonary resuscitation was performed for 60 minutes at the emergency room in vain. Autopsy was done to find out the cause of sudden death and the etiology of complete heart block. Microscopic focal infarctions with scar formation were noted along the course of conduction system in the interventricular septum, which might be the main cause of complete heart block during the attack of severe bronchopneumonia complicated with acute bacterial endocarditis. The tip of the pacemaker wire was slipped from the granulation scar at the apex of the right ventricular cavity, and this might be the direct cause of pacing failure and death.

• STI Policy Review
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• 제4권1호
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• pp.94-118
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• 2013

Innovation plays a large role in green growth. While it is a widely accepted view that, without innovation, it would be very difficult and costly to address major environmental issues, innovation itself tends to be constrained by limited access to eco-financing and is inherently risky, often requiring a long-term horizon. Although global consensus is more or less established as to the urgency and necessity of accelerating green innovation, the quality and quantity of financing in this area is largely insufficient, with increasing funding gaps in many countries. A new financial mechanism is urgently needed in order to re-orient financial flow and enable innovators to overcome the valleys of death that occur throughout the innovation cycle. A number of different modalities exist in financing the commercialisation of eco-innovation. Existing mechanisms have not been as successful as expected, revealing critical limits to furthering certain types of projects that are essential for economic and environmental progress. Experts' estimations have shown that the funding gap will widen in the coming years as demand for clean energy and green infrastructure rises, and as green technologies and innovation develop faster than the market for it can develop. Against this backdrop, the main purpose of this research is threefold: to identify issues and problems regarding current means of funding for eco-innovation and green projects; to provide insight into securing longterm green financing by looking at European cases; and ultimately to suggest policy implications for designing and implementing eco-specific financial instruments, focusing on governments' roles in sustainable financing for eco-innovation. This study analyses different models of financing mechanisms, a mix of public and private funds, in view of suggesting conditions for the sustainable financing of green projects, especially for large-scale high-risk projects. Based on the findings from the analyses of mechanisms and the shortcomings of the existing funding modalities, this study ultimately suggests policy implications for effectively supporting the commercialisation of eco-innovation.

• Journal of Chest Surgery
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• 제23권3호
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• pp.438-451
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• 1990

Pneumatic total artificial heart[TAH] has been clinically applied for the purpose of permanent or temporary use followed by cardiac transplantation in the patients with end stage heart diseases. In spite of the good durability of the pneumatic TAH, thrombus formation, bleeding and infection resulted in death. The Tomasu heart, which is a type of pneumatic TAH, was used in this study. This model is a modified Jarvik heart and consists of atrial cuffs, outflow vascular grafts and thin-layer seamless diaphragm type of ventricles. Cardiac outputs of the left artificial heart were measured by Donovan`s mock circulation under variable conditions of driving parameters, and an experimental artificial heart implantation was performed in 4 calves to observe the changes of hemodynamic parameters in early postoperative period and hematologic and bio-chemical changes in a long-term survival case. In the mock circulation test, cardiac output of the heart was increased with the increase of the left atrial pressure and left driving pressure. Maximum cardiac output was obtained at the heart rate of 120 to 130/min and percent systole of 40 to 45Zo under the condition of a constant left driving pressure of 180mmHg and left atrial pressure of 10mmHg. During the first 24 hours of TAH pumping, driving pressure ranged from 178$\pm$5mmHg to 187$\pm$8mmHg for the left heart and from 58$\pm$6mmHg to 78$\pm$28mmHg for the right heart. The Mean arterial pressure significantly increased between 2 and 8 hours after the start of pumping. The survival time ranged from 27 hours to 46 days. The causes of death were respiratory failure in 2 cases, mechanical valve failure in one, and left ventricular outflow obstruction due to thrombus in a 46-day survival case. This study demonstrated that Tomasu artificial heart operated effectively during the first 24 hours of artificial heart pumping, but thrombus formation around the valve holding area was the main problem in long-term survival case.

• Journal of Korean Neurosurgical Society
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• 제41권1호
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• pp.30-38
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• 2007

Objective : To elucidate the role of aquaporin-4[AQP4] in cerebral edema formation, we studied the expression and subcellular localization of AQP4 in astrocytes after focal cerebral ischemia. Methods : Cerebral ischemia were induced by permanent middle cerebral artery[MCA] occlusion in rats and estimated by the discoloration after triphenyltetrazolium chloride[TTC] immersion. Change of AQP4 expression were evaluated using western blot. Localization of AQP4 was assessed by confocal microscopy and its interaction with ${\alpha}-syntrophin$ was analyzed by immunoprecipitation. Results : After right MCA occlusion, the size of infarct and number of apoptotic cells increased with time. The ratio of GluR1/GluR2 expression also increased during ischemia. The polarized localization of AQP4 in the endfeet of astrocytes contacting with ventricles, vessels and pia mater was changed into the diffuse distribution in cytoplasm. The interactions of AQP4 and Kir with ${\alpha}-syntrophin$, an adaptor of dystrophin complex, were disrupted by cerebral ischemia. Conclusion : The deranged spatial buffering function of astrocytes due to mislocalized AQP4/Kir4.1 channel as well as increased assembly of $Ca^{2+}$ permeable AMPA receptors might contribute to the development of edema formation and the excitotoxic neuronal cell death during ischemia.

• 대한한의학원전학회지
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• 제24권6호
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• pp.15-28
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• 2011

Gwan-Gyeok(關格) is one of the dangerous conditions that can lead to death and is considered important in clinical practice. However its true concept is unclear and arguments on the subject have been diverse over generations. This kind of confusion is largely due to an insufficient understanding of the study results on Nangyeong(難經). In Nangyeong, Gwan-Gyeok is divided into 'in bowels(在腑)' and 'in viscera(在臟) and distinction is made between 'damaged by heat(傷熱)' and 'damaged by dampness(傷濕) thus establishing a broad outline of differentiation of syndrome(辨證). Moreover, the clinical progress is systematically divided into 3 stages thus providing a very useful viewpoint on diagnostics. A sharp perspective on the pathogenesis is also shown by emphasizing the kidney and Myeongmun(命門) through the comparison between cheok pulse(尺) and chon pulse(寸). This point of view in Nangyeong is truly proposing a permanent standard on the understanding of Gwan-Gyeok. Therefore it is the author's hope that this study will work as a start to look back on the flow of the research on Gwan-Gyeok which has been rather confusing since Sanghallon(傷寒論).

• Journal of Chest Surgery
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• 제26권12호
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• pp.915-919
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• 1993

The management of Patent Ductus Arteriosus[PDA] with heart failure and cardiac cachexia in premature infants have been a disturbing and controversial problem in the field of pediatric cardiovascular surgery.We analysed our experiences to determine the rationale of surgical closure of PDA in infants . During a period of 7 years from January 1986 to December 1992, 12 infants under 2 months of age underwent operations for "hemodynamically significant" PDA which had caused severe heart failure.There were 6 male and 6 female patients. Their mean gestational age was 33.8 weeks and their mean body weight was 1990 g. ranged from 710 g. to 2900 g. Mean age at operation was 28.5days. Seven patients had history of Indomethacin trial. All patients were operated with double ligation technique under general anesthesia.There was no mortality and blood transfusion was not necessary in any patient during the operation.In all cases, we could confirm the complete closure of PDA after operation by follow-up echocardiography.Two patients died during their hospital stay and 1 patient died at 6 months after operation. The causes of death were sepsis with congestive heart failure, necrotizing entero colitis and pneumonia respectively.We can not detect any operation related complication which resulted in permanent sequelae as well as delayed complications related to nerve damage. These results indicate that surgical ligation of PDA in infants with severe heart failure is relatively safe and effective.effective.

• 고려인삼학회:학술대회논문집
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• 고려인삼학회 1998년도 Advances in Ginseng Research - Proceedings of the 7th International Symposium on Ginseng -
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• pp.21-30
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• 1998

Ginseng root has been considered to prevent neuronal degeneration associated with brain ischemia, but experimental proof in support of this speculation is limited. Moreover, few studies have compared the neuroprotective actions of ginseng ingredients with those of peptide growth factors and cytokines isf vivo. Using a gerbil forebrain ischemia model, we demonstrated that the oral administration of red ginseng powder before an ischemic insult prevents delayed neuronal death in the hippocampal CAI field and that a neuroprotective molecule within red ginseng powder is ginsenoside Rbl. The neurotrophic effect of ginsenoside Rbl, when examined in the gerbil ischemia model and in neuronal cultures was as potent as or more potent than the effects of epidermal growth factor, ciliary neurotrophic factor, erythropoietin, prosaposin, interleukin-6 and interleukin-3. Besides the protection of hippocampal CAI neurons against brain ischemia/repercussion injuries, ginsenoside Rbl was shown to prevent place navigation disability, cortical infarction and secondary thalamic degeneration in stroke-prone spontaneous hypertensive rats with permanent occlusion of the unilateral middle cerebral artery distal to the striate branches. These findings may validate the empirical use of ginseng root for the treatment of cerebrovascular diseases