• Journal of Chest Surgery
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• v.17 no.2
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• pp.244-249
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• 1984

Surgical treatment of partial endocardial cushion defect was accomplished in Feb. 1984 in this department. The 5 year old male patient had history of frequent upper respiratory tract infection and since his age of 3 years dyspnea on exertion and palpitation were noted but there were no cyanosis and clubbing. A thrill was palpable on the apex and grade IV/IV harsh systolic ejection murmur and diastolic murmur was audible on it. Liver was palpable about 3 finger breadths and no ascites. Chest X-ray revealed increased pulmonary vascularity, moderate cardiomegaly [C-T ratio; 0.69], and enlarged left atrium. EKG showed first degree heart block, RVH, LVH, and LAD. Echocardiogram showed paradoxical ventricular septal movement and abnormal diastolic movement of the anterior leaflet of mitral valve. Right heart catheterization resulted left to right shunt [Qp:Qs:2.1:1 ] and moderate pulmonary hypertension [60/40 mmHg]. Left ventriculogram showed mitral regurgitation [Grade III/IV] and filling of left atrium and right atrium nearly same time. Operative findings were: 1.Primum type atrial septal defect [3x2 cm] 2.Cleft on the anterior leaflet of mitral valve. 3.No interventricular communication and cleft of tricuspid valve leaflet. The mitral cleft was repaired with 4 interrupted sutures. The primum type atrial septal defect was closed with Dacron patch intermittently at endocardial cushion and continuously remainder. The post operative course was uneventful and discharged on 22nd postoperative day in good general conditions.

• Journal of Nutrition and Health
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• v.37 no.7
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• pp.576-584
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• 2004

The purpose of this study was to evaluate the effects of Web-based nutrition education program for junior and senior high school students. Three materials, which were printed materials on Group I, WBI (Web-Based Instruction) leaflet on Group II and the web-based nutrition education program developed in the antecedent research, were applied for 564 students in 3 junior high school and 4 senior high school in Seoul during 4 weeks. Pre-test was done from October 21 to October 26, 2002 and post-test was done from November 25 to December 13, 2002. The statistical data analysis was completed using SPSS WIN (ver. 11.0) for descriptive analysis, t-test and ANOVA. According to the evaluation of effectiveness for web-based nutrition education program, nutrition knowledge, food attitude, food habit and nutrient intake were not significantly improved but positively. And on the evaluation of effectiveness for nutrition education program by materials, WBI was more effective educational materials than WBI leaflet and printed materials. Consequently nutrition knowledge, food attitude, food habit and nutrient intake were improved positively but not significantly using WBI, which was due to the instructional period of the only 4 weeks. Therefore long-term instruction should be required for effective nutrition program, as well as more WBI nutrition education program for high school students would need to be developed in the near future in that WBI was effective material on nutrition education.

• The Plant Pathology Journal
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• v.33 no.3
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• pp.345-349
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• 2017

Tomato chlorosis virus (ToCV), a member of the genus Crinivirus, has caused an epidemic disease in tomato worldwide. ToCV is phloem-limited and transmitted by whiteflies in a semi-persistent manner, but not by mechanical inoculation. Experimental propagation of ToCV has been performed primarily by using whitefly-mediated inoculation. To develop a simple and convenient method for transmission of ToCV, we investigated grafting single-leaflets from tomato plants infected with ToCV to recipient tomato seedlings. Forty-one of 46 tomato seedlings tested were grafted successfully with single-leaflets infected with ToCV. Among them, 36 seedlings (87.8%) were systemically infected with ToCV and developed typical symptoms. Our results demonstrated that single-leaflet grafting could provide a sufficient amount of inoculum for the transmission of ToCV to the grafted seedlings.

• Journal of the Korean Society of Visualization
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• v.16 no.2
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• pp.31-37
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• 2018

Ischemic mitral regurgitation (IMR) is the primary mitral valve (MV) pathology in the aftermath of myocardial infarction as a consequence of regional left ventricular (LV) remodeling. We investigated the effect of asymmetric papillary muscle (PM) displacement and annular dilation on IMR development. Virtual MV modeling was performed to create a normal human MV. Asymmetric PM displacement, asymmetric annular dilation, and the combination of these two pathologic characteristics were modeled. Dynamic finite element evaluation of MV function was performed across the complete cardiac cycle for the normal and three different IMR MV models. While the normal MV demonstrated complete leaflet coaptation, each pathologic MV model clearly revealed deteriorated leaflet coaptation and abnormal stress distributions. The pathologic MV model having both asymmetric PM displacement and annular dilation showed the worst leaflet malcoaptation. Simulation-based biomechanical evaluation of post-ischemic LV remodeling provides an excellent tool to better understand the pathophysiologic mechanism of IMR development.

• Journal of Biomedical Engineering Research
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• v.17 no.1
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• pp.49-60
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• 1996

An experimental investigation was performed under steady flow condition to assess hydrodynamic performance of floating-type monoleaflet polymer valves (MLPV) withdifferent leaflet thickness. The St. Jude Medical valve (SJMV) was also used for comparison test. Pressure drops of MLPVS are larger than those for other types of polymer valves and mechanical valves. Furthermore, the thicker is the leaflet thickness of the polymer valve, the larger are the corresponding pressure drop. The velocity profiles for MLPs reveal a large reversed flow region downward to the valve position. The maximum wall shear stresses of MLPVS at a flow rate of $30{\ell}$/min are in the range 50-130 dyn/$cm^2$, and the corresponding maximum Reynolds shear stresses are in the range of 100-500 dyn/$cm^2$, respectively, which are beyond the allowable limit clinically. In contrast, floating-type monoleaflet polymer valves show better hydrodynamic performance in leakage volume. From the designing point of view, it may be concluded that the optimum thickness of leaflet for better hydrodynamic performance is one of the Important parameters.

• Proceedings of the KOSOMBE Conference
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• v.1995 no.05
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• pp.241-246
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• 1995

An experimental investigation was performed under steady flow condition to assess hydrodynamic performance of floating-type monoleaflet polymer valves (MLPV) with different leaflet thickness. The St. Jude Medical valve (SJMV) was also used for comparison tests. Pressure drops of MLPVs are larger than those for other types of polymer valves and mechanical valves. Furthermore, the thicker is the leaflet thickness of a polymer valve, the larger arc the corresponding press drop. The velocity profiles for MLPV reveal a large reversed flow region downward to the valve position. The maximum wall shear stresses of MLPVs at a flow rate of 30 l/min are in the range $54-130\;dyn/cm^2$, and the corresponding maximum. Reynolds shear stresses are in the range of $100-500\;dyn/cm^2$, respectively. Both arc beyond the allowable limit clinically. In contrast, floating-type monoleaflet polymer valves show better hydrodynamic performance in leakage volume. From the designing point of view, it can be concluded that the optimum thickness of leaflet for better hydrodynamic performance is one of the important parameters.

• Journal of Mechanical Science and Technology
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• v.20 no.8
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• pp.1118-1124
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• 2006

Recently, cavitation on the surface of mechanical heart valve has been studied as a cause of fractures occurring in implanted Mechanical Heart Valves (MHVs). It has been conceived that the MHVs mounted in an artificial heart close much faster than in vivo sue, resulting in cavitation bubbles formation. In this study, six different kinds of mono leaflet and bileaflet valves were mounted in the mitral position in an Electro-Hydraulic Total Artificial Heart (EHTAH), and we investigated the mechanisms for MHV cavitation. The valve closing velocity and a high speed video camera were employed to investigate the mechanism for MHV cavitation. The closing velocity of the bileaflet valves was slower than that of the mono leaflet valves. Cavitation bubbles were concentrated on the edge of the valve stop and along the leaflet tip. It was established that squeeze flow holds the key to MHV cavitation in our study. Cavitation intensity increased with an increase in the valve closing velocity and the valve stop area. With regard to squeeze flow, the bileaflet valve with slow valve-closing velocity and small valve stop areas is better able to prevent blood cell damage than the monoleaflet valves.

• Journal of Chest Surgery
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• v.40 no.6 s.275
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• pp.441-444
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• 2007

Sliding annuloplasty has been used for mitral valve repair in conjunction with posterior leaflet quadrangular resection to avoid systolic anterior motion of the anterior leaflet of the mitral valve. Herein, we report on a case of successful mitral valve repair with using the annular plication technique to facilitate sliding annuloplasty and extensive quadrangular resection was also done for treating a Marfan's syndrome patient who had an extremely redundant leaflet and a severely dilated annulus.

• Korean Parent-Child Health Journal
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• v.22 no.1
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• pp.1-9
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• 2019

Purpose: The purpose of this study is to develop educational material for parents of hospitalized preschool children who receive nebulizer therapy treatment. The educational material is aimed at providing information on the correct use of nebulizer. Methods: The development of educational material was based on the ADDIE model and consists of an A4-sized leaflet and a video. Results: The leaflet included basic information, procedures, and cautionary information for nebulizer therapy, as well as frequently asked questions. The one minute and fifty second video is accessed via QR code and provides step-by-step instruction on nebulizer therapy. Conclusion: This study recommends that the educational leaflet and video developed for nebulizer therapy use be provided to parents of preschool children hospitalized in the pediatric ward.

• Journal of Chest Surgery
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• v.29 no.3
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• pp.331-336
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• 1996

Four operative cases of aortic valvuloplasty with leaflet extension technique using glutaraldehyde preserved tautologous pericardium are described. All patients had severe aortic regurgitation on preoperative echocardiogram, and Grade W AR on oath-angiogram. The causes of aortic regurgitation were rheumatic fever in 2 cases, degenerative change in 1 case, and 1 case of unknown cause. The autologous pericardium was fixed In a 0.625% glutaraldehyde solution for 15 minutes and rinsed in saline for an additional 15 minutes. Leaflet extension technique varied in 4 patients depending on the site and the extent of the leaflet size and lesion. There was no hospital mortality and no thromboembolic episode without anticoagulation. Post-operative cardiac size was reduced on simple chest film in all cases, and LVESD and LVEDD were reduced on folio w- up echo cardi o gram . This experience permits us to conclude that leaflet extension technique is simple and safe in valve r construction, allowing repair of aortic valves that need to be replaced.