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A Study of Optimal Model for the Circuit Configuration of Korean Pulsatile Extracorporeal Life Support System (T-PLS) (한국형 박동식 생명구조장치(T-PLS) 순환회로를 위한 최적화 모델 연구)

  • Lim Choon Hak;Son Ho Sung;Lee Jung Joo;Hwang Znuke;Lee Hye Won;Kim Kwang Taik;Sun Kyung
    • Journal of Chest Surgery
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    • v.38 no.10 s.255
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    • pp.661-668
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    • 2005
  • Background: We have hypothesized that, if a low resistant gravity-flow membrane oxygenator is used, then the twin blood sacs of TPLS can be located at downstream of the membrane oxyenator, which may double the pulse rate at a given pump rate and increase the pump output. The purpose of this study was to determine the optimal configuration for the ECLS circuits by using the concept of pulse energy and pump output. Material and Method: Animals were randomly assigned to 2 groups in a total cardiopulmonary bypass model. In the serial group, a conventional membrane oxygenator was located between the twin blood sacs. In the parallel group, the twin blood sacs were placed downstream of the gravity-flow membrane oxygenator. Energy equivalent pressure (EEP) and pump output were collected at pump-setting rates of 30, 40, and 50 BPM. Result: At the given pump-setting rate, the pulse rate was doubled in the parallel group. Percent changes of mean arterial pressure to EEP were $13.0\pm1.7,\; 12.0\pm1.9\;and\;7.6\pm0.9\%$ in the parallel group, and $22.5\pm2.4,\; 23.2\pm1.9,\;and\;21.8\pm1.4\%$ in the serial group at 30, 40, and 50 BPM of pump-setting rates. Pump output was higher in the parallel circuit at 40 and 50 BPM of pump-setting rates $(3.1\pm0.2,\;3.7\pm0.2L/min\;vs.\;2.2\pm0.1\;and\;2.5\pm0.1L/min,\;respectively,\;p=0.01)$. Conclusion: Either parallel or serial circuit configuration of the ECLS generates effective pulsatility. As for the pump out, the parallel circuit configuration provides higher flow than the serial circuit configuration.

Surgical Outcome of Tetralogy of Fallot in Adolt -Implication of Preoperative Cyanosis- (수술 전 청색증 정도에 따른 성인 활로씨 4징증의 임상 양상)

  • Kim Sang-hwa;Park Soon-Ik;Park Jung-Jun;Song Hyun;Lee Jae-Won;Seo Dong-Man;Song Meong-Gun;Song Jong-Min;Kang Duck-Hyun;Song Jae-Kwan;Jang Wan-Sook;Kim Young-Hwue;Yun Tae-Jin
    • Journal of Chest Surgery
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    • v.38 no.4 s.249
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    • pp.271-276
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    • 2005
  • We analysed differences in operative methods and postoperative outcome according to the severity of preoperative cyanosis in adult ToF (Tetralogy of Fallot) patients. Material and Method: From August 1989 to June 2001, thirty three adult patients, 18 females and 15 males, underwent total correction for ToF. Their age ranged from 15 years to 54 years (median: 34). Patients were divided into 2 groups by preoperative $SaO_2$ (arterial oxygen saturation): group I$(n=cyanotic,\;SaO_2\;\geq94\%)$ and group II $(acyanotic,\; SaO_2\geq95%)$. Preoperative median hemoglobin level was higher in group I compared to group II (17.5 g/dl vs 15 g/dl). Postoperative follow-up duration ranged from 1 to 94 months (670 patient-month, median: 14 months), and 63 two-dimensional echocardiographic examinations were done during this period. Result: There were no early or late mortality. With regard to RVOT (right ventricular outflow tract) reconstruction, trans-annular patch and RV-PA extracardiac conduit were used in 7 and 3 patients respectively, and all of them belonged to group I. In group I, cardiopulmonary bypass time, aortic cross-clamping time, ICU day, hospital day were significantly longer than in group II, and postoperative inotropic support was significantly greater than in group II. There was no ventricular arrhythmia in both groups, and one patient in group I suffered from atrial arrhythmia, which was resolved spontaneously after tricuspid and pulmonary valve replacement. During follow-up periods, functional class, residual RVOT stenosis and pulmonary regurgitation, tricuspid regurgitation, occurrence of ventricular and atrial arrhythmias were comparable between two groups. Conclusion: In adult ToF patients with severe preoperative cyanosis, more aggressive RVOT reconstruction and careful postoperative care are mandatory. However intermediate-term outcome of this group of patients is comparable to the patients with minimal or no preoperative cyanosis.

Study on Antioxidant Potency of Green Tea by DPPH Method (DPPH 방법을 통한 녹차의 항산화 활성에 대한 연구)

  • 오중학;김은희;김정례;문영인;강영희;강정숙
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.33 no.7
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    • pp.1079-1084
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    • 2004
  • The present study was conducted to compare antioxidant activity of green teas, fermented teas and other related common teas by examining radical scavenging activity using DPPH (2,2 diphenyl l-picryl hydrazyl). Scavenging activity ($SC_{50}$/) of epigallocatechin gallate (EGCG) for 0.1 mM DPPH radical was 5.5 $\mu$M or 4.2 mg/L by weight, then catechin, 14 $\mu$M or 2.5 mg/L and vitamin C, 22 $\mu$M or 3.9 mg/L, respectively. Kyokuro tea (okro) powder of 24.2 mg/L or green tea powder of 25.2 mg/L was used to reach $SC_{50}$/ for 0.1 mM DPPH. One serving of 2 g green tea provides antioxidant activity equivalent to 109∼147 mg EGCG, 145∼185 mg catechin or 131∼168 mg vitamin C. Teas from the first harvest had the highest radical scavenging activity when compared with later harvest green teas grown in the same region, but there is virtually no difference by the harvest time. A Chinese green tea, Dragon well had the highest antioxidant activity among other green teas tested providing antioxidant capacity equivalent to 168 mg EGCG or 188 mg vitamin C per 2 g serving, but partially fermented Chinese teas had much lower antioxidant activity than any green tea tested. Black tea which is fully fermented showed as strong antioxidant activity as green teas (76.3 mg vs 86.7∼67.6 mg per tea bag). One tea bag of green teas from market provided antioxidant capacity equivalent to 52∼86 mg EGCG, 70∼105 mg catechin or 63-96 mg vitamin C. Teas made of persimmon leaf, pine needle, mulberry leaf had comparatively low anti-oxidant activity equivalent to 2.5∼4.8 mg EGCG or 15∼21 mg vitamin C per teabag. The third brewed green tea still had enough antioxidant activity, while tea from tea bag brewed for 3 min or 5 min did not have any difference in their antioxidant activity. More systemic studies are needed to clarify the relationship between tea catechins and antioxidant capacity focusing on how growing, harvest time, fermentation and other processes can influence on this.

Coronary Artery Bypass Graft Surgery in the Elderly (고령환자의 관상동맥 우회로 조성술)

  • 김학제;황재준;김현구;신재승;손영상;최영호
    • Journal of Chest Surgery
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    • v.32 no.8
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    • pp.715-721
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    • 1999
  • Background:The number of old patients receiving coronary artery bypass grafting(CABG) is increasing. With the more recent advances in operative techniques, the age at which CABG is indicated has also increased. This study evaluated the risk factors associated with the hospital mortality and the morbidity following CABG in elderly patients. Material and Method: Between March 1991 and June 1998, we retrospectively reviewed 45 consecutive patients aged 65 years or older who underwent CABG. We compared the data with the results of 179 patients under the age 65 years operated during the same period. Result: Mean age was 68${\pm}$1.41 years(range 65 to 74 years). Emergency surgery was required in 4, and elective surgery in 41 patients. The mean number of distal anastomosis per patient was 3.62 ${\pm}$0.81 and mean aortic cross-cramp time was 69.84${\pm}$18.5 minutes. Thirty patients had Canadian class III or IV preoperatively, but 43 patients had class I or II postoperatively. The left ventricular ejection fraction increased significantly from 54.23${\pm}$10.62% preoperatively to 58.14${\pm}$9.88% postoperatively(p<0.05). Postoperative complication was pneumonia in 2 patients, acute renal failure in 2 patients, sternal wound infection in 1 patient, and postoperative myocardial infarction in 1 patient. There were two postoperative deaths. The causes of deaths were low output syndrome in one patient, and sepsis due to pneumonia in the other patient. The hospital mortality was higher in the elderly group(4.4 versus 2.86%) but was not statistically significant(p>0.05). Incremental risk factors for hospital deaths in the elderly were emergent operation, preoperative PTCA, postoperative use of IABP and postoperative ARF(p<0.05). The duration of hospital stay after operation was significantly longer for the elderly group than the younger group(19.27${\pm}$12.51 vs 15.55${\pm}$6.99 days; p< 0.05). Follow-up was complete for 34 of the hospital survivors and ranged from 1 to 73 months(mean: 23.58${\pm}$19.56 months). There was no late mortality of cardiac origin. Conclusion: Age is an important factor in selecting optimal management for elderly patients with coronary compromise, but age alone should not dictate the choice of therapy. Coronary artery bypass surgery in the elderly is associated with acceptable early mortality and excellent long-term results.

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Mid-term and Long-term Outcomes of Posterior Plication Annuloplasty(Modified Davila Annuloplasty) for Functional Tricuspid Regurgitation (기능성 삼첨판막부전증에 대한 삼첨판후판륜주름술(Davila Technique)의 중장기결과)

  • Lee, Mi-Kyung;Kim, Jong-Hun;Kim, Min-Ho;Jo, Jung-Ku;Choi, Jong-Bum
    • Journal of Chest Surgery
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    • v.41 no.5
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    • pp.580-585
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    • 2008
  • Background: Many types of tricuspid annuloplasty are used in surgical correction of functional tricuspid regurgitation (FTR). We evaluated the mid-term and long-term outcomes in patients treated with a posterior annular plication technique (a modified Davila technique) for FTR. Material and Method: Between January 1991 and August 2006, 58 adult patients (male, 22; female, 36) with FTR of grade 2/4 or more or with tricuspid annular dilatation of more than 5.0cm in diameter, even with an FTR of less than grade 2, had received a posterior annular placation. Preoperatively, 26 patients (44.8%) had a grade 3 or more FTR. All patients had received a mitral valve replacement, and 20 (34.5%) had concomitant aortic valve replacement. Result: During the mean follow-up period of $101.4{\pm}51.6$ months, FTR disappeared or remained trivial in 28 patients (49.1%), was grade $2{\sim}3$ (${\geq}$grade 2 and $2.66{\pm}0.73\;vs.\;0.82{\pm}0.89$; p<0.0001). Patients did not require a second surgery for FTR and did not show further FTR aggravation. Conclusion: The modified Davila posterior annular plication technique for FTR has reasonable mid-term and long-term results and is a useful surgical procedure.

The Differentiation of the Cholinergic Nerve Cells at the Meynert Basal Nucleus of the Basal Forebrains in the Growth Period of Rat (흰쥐 전뇌 기저부 Meynert기저핵에서 출생 후 발육기간에 따른 콜린성 신경세포의 분화)

  • Hahm, Young-Ok;Kim, Soo-Jin
    • Applied Microscopy
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    • v.31 no.4
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    • pp.355-365
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    • 2001
  • This study was performed to investigate the distribution and differentiation on the immunoreacted cells of the ChAT (choline acetyltransferase) at the Meynert basal nucleus of the forebrains in the growth periods of rat, using the immunohistochemistric method. According to the cell shape and the ratio of long axis vs short axis of cell soma, the ChAT antibody reacted nerve cells in the Meynert basal nucleus of the rats were classified into six types. In the adult rats, the FD (frequency distributions) of round, oval and elongated cells were maximum. The FD of these types were shown to be progressively decreased during the postnatal development. In addition, the FD of elongated nerve cells in were observed in the adult rats respectively. This was thought to be the same phenomenon as those in the round and oval cells . The total mean volume of ChAT antibody reacted cell somata was lowest in the PND (postnatal days) 7 rats and was highest in the PND 21 rats. But, those were decreased to the adult. These results suggest that ChAT antibody reacted nerve cells grow up to PND 21 and then, differentiate into the various types by neurites outgrowing. On the electron micrography, the adult rat forebrain cells were obtained to be well developed ribosomes, polysomes , rough endoplasmic reticula and mitochondria. The immunreactivities were observed in ribosomes, polysomes, rough endoplasmic reticula and outer membrane of mitochondria. Golgi complexes were poorly developed and not showed jmmunreactivity. The ribosomes , polysomes and endoplasmic reticula are considered to be closely related to the inter cellular localization and biosynthesis of the ChAT but not Golgi complex. According to the results in the present study, it is considered that the ChAT-immunoreacted nerve cells in the Meynert basal nucleus of the rat forebrains are differentiated throughout the postnatal development with following processes of changes; 1) the cholinergic nerve cells develop postnatally 2) cell soma volumes gradually increase during the early postnatal days 3) and then, cells differentiate into the various types by projecting the neurites to the appropriate area after PND 21.

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Study of the Effects of Ambient Temperature and Car Heater Power on the Train Cabin Temperature (외기 온도와 난방 출력의 철도차량 객실 온도에 대한 영향 연구)

  • Cho, Youngmin;Park, Duck-Shin;Kwon, Soon-Bark;Jung, Woo-Sung
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.15 no.9
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    • pp.5877-5884
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    • 2014
  • Recently, abnormally cold weather has been reported more frequently in winter due to the climate change and abnormal weather changes. On the other hand, the heating capacity of a railcar may be not enough to warm the cabin under severe cold climatic conditions, which is one of the reasons for the passengers' complaints about heating. In this study, the effects of ambient temperature and heater power on the cabin temperature was investigated to obtain the minimum ambient temperature for the tested railcar. The test railcar was placed in a large-climatic chamber, and various ambient temperature conditions were simulated. The effects of the heater output were investigated by monitoring the cabin temperature under a range of heater output conditions. The mean cabin temperature was $14.0^{\circ}C$, which was far lower than the required minimum temperature of $18^{\circ}C$, under a $-10^{\circ}C$ ambient temperature condition with the maximum heat power. When the ambient temperature was set to $0^{\circ}C$ and $10^{\circ}C$, the maximum achievable cabin temperature was $26.1^{\circ}C$ and $34.0^{\circ}C$. Through calculations using the interpolation method, the minimum ambient temperature to maintain an $18^{\circ}C$ cabin temperature was $-6.7^{\circ}C$ for this car. The vertical temperature difference was higher with a higher power output and higher ambient temperature. The maximum vertical temperature difference was higher than $10^{\circ}C$ in some cases. However, the horizontal temperature difference vs. low temperature (< $2^{\circ}C$) was independent of the power output and ambient temperature. As a result, it is very important to reduce the vertical temperature difference to achieve good heating performance.

Evaluation of cardiac function by tissue Doppler imaging in children with cancer (Tissue Doppler imaging을 이용한 소아 종양 환자에서의 심기능 평가)

  • Kim, Yeo Hyang
    • Clinical and Experimental Pediatrics
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    • v.49 no.4
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    • pp.417-423
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    • 2006
  • Purpose : The objectives of this study were to assess ventricular function by tissue Doppler imaging in children who were receiving chemotherapy or who had received chemotherapy, and to apply repeated tissue Doppler imaging to make an early assessment in cardiac toxicity studies. Methods : This study was conducted on 23 oncology patients on-treatment or off-treatment from April 2005 to July 2005 at Dongsan Medical Center, Keimyung University. All patients(group 1) were divided into two groups, fractional shortening(FS) over 29 percent(group 2) and FS under 28 percent (group 3) in the first category. These same patients were also divided into the following groups : group treated with anthracyclin(group 4) and group treated without anthracyclin(group 5). Deceleration time(DT), isovolumic relaxation time(IVRT), FS, peak early diastolic(E), and peak late diastolic (A) velocity of transmitral flow were measured by M-mode and pulsed wave Doppler. Systolic(Sm), peak early diastolic(Em), and peak late diastolic(Am) velocity in apical 4-chamber and 2-chamber views were measured by tissue Doppler imaging. The author calculated a modified Tei index, E/A, E/Em ratio by using measured values. Results : Twenty three patients were enrolled : 12 boys and 11 girls. The average age of patients was 8 years and 4 months. Thirteen out of 23 patients were in the group treated with anthracyclin (group 4) and 6 had FS under 28 percent(group 3). E/Em ratio showed a significant difference between group 1 and control group($6.46{\pm}1.85$ vs $7.06{\pm}1.64$, P<0.05). Other parameters had no difference statistically. Conclusion : This study showed that the change of cardiac function developed earlier in diastolic function than in systolic function, as E/Em ratio reflecting the mean LV diastolic pressure showed a significant difference between the control group and chemotherapy groups. Echocardiography using tissue Doppler imaging is a non-invasive, comfortable and reliable method for post-chemotherapy follow up.

Complete Myocardial Revascularization Utilizing Parallel Secluential Anastomoses (Parallel sequential anastomosis를 이용한 관상동맥 우회수술의 성적)

  • 박계현;김관민
    • Journal of Chest Surgery
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    • v.30 no.7
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    • pp.647-655
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    • 1997
  • We evaluated the feasibility and safety of this method by reviewing the early outcome of the patients who underwent coronary artery bypass grafting(CABG) utili ing parallel sequential anastomoses with saphenous vein grafts, comparing with the outcome of the patients revascularized with grafts having only single distal anastomosis. During the one-year period of 1995, a total of 79 patients underwent isolated CABG, among whom 39 patients with sequential vein grafts(sequential group) and 40 patients without sequential grafts(non-sequential group). There was no difference between the two groups in terms of preoperative status, except in the extent of the coronary disease; 87.2% of the sequential group and 45.0% of the non-sequential group had left main andlor triple vessel involvement. 318 distal coronary anastomoses were done; 198 for the sequential group(5.1/patient) and 120 for the non-sequential group(3.0/patient). In the sequential group, the mean durations of cardiopulmonary bypass and aortic clamp per one distal anastomosis were 33.5 and 21.1 minutes, respectively. In the non-sequential group, these were 41.8 and 22.7 minutes. There were two operative deaths, both in the non-sequential group. There was no difference in the incidence of postoperative complications including myocardial infarction. During the follow-up period(2 to 15 months), 8 patients(3 in the sequential and 5 in the nonsequential group) complained of residual or recurrent angina. Comparison of preoperative and postoperative ."'Thallium myocardial perfusion scans in 30 patients showed improved or normal perfusion reserve in 83.3% of segments bypassed with sequential grafts and 82.5% of segments bypassed with non-sequential graft(5), These results show that, utilizing parallel sequential anastomoses with saphenous vein grafts, we could achieve satisfactory short-term clinical results in patients with extensive coronary stenoses. So, we conclude that this technique is a safe, technically feasible strategy for CABG, which can achieve the aim of complete myocardial revascularization with a limited length of graft.raft.

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Underlying Etiologic Factor of Recurrent Pneumothorax after Bullectomy (원발성 기흉환자에서 재수술의 원인)

  • 윤용한;이두연;김해균;홍윤주
    • Journal of Chest Surgery
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    • v.32 no.6
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    • pp.556-560
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    • 1999
  • Background: The cause of spontaneous pneumothorax is not yet but it is certain that intrathoracic air comes from ruptured bulla. Video-assisted thoracoscopic surgery(VATS) or open thoracotomy is recommended for thoracic incision in recurrent pneumothorax. However, recurrent rate after bullectomy with the VATS is very high compared to mini-thoracotomy, 3% to 20% and below 2%, respectively. Material and Method: This retrospective analysis was performed on 16 re-operated cases among 446 surgically treated pneumothorax of the 737 cases of spontaneous pneumothorax diagnosed at Yongdong Severance Hospital from Nov. 1992 to June 1997. Result: Among the 446 surgically-treated patients in 737 case of spontaneous pneumothorax, 16 patients underwent re-operation, showing a 3.5% re-operation rate. Male-to-female ratio was 15 to 1 and mean age at initial attack was 20.2 years(ranging from 15 to 50). Mean hospital stay was 6.34 days(ranging from 2 to 20 days) and mean chest tube indwelling period was 4.2 days(ranging from 1-10 days). Median follow-up was 46 months(range 10-66 months). Three different surgical methods were applied : video-assisted thoracoscopic surgery(VAST) in 281 cases, of whom 2 underwent local anesthesia; subaxillary mini-thoracotomy in 159 cases and limited lateral thoracotomy in the remaining 6 cases. Three different re-operative surgical methods were applied ; video-assisted thoracoscopic surgery (VAST) in 6 cases, subaxillary mini-thoracotomy in 9 cases, and limited lateral thoracotomy in the remaining 1 case. The underlying etiological factors of the recurrent pneumothorax after bullectomy were o erlooking type(9) and new growing type(7). Mean recurrent period from previous operation was 1 month for overlooking type and 18 months for new growing type. Conclusion: The underlying etiological factors of recurrent pneumothorax lead to re-operation were new-growing and over-looking type. We need additional treatments besides resecting blebs of prevent the recurrence rate and more gentle handling with forceps due to less damage to the pleura.

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