Dynamic change of mitral apparatus as potential cause of left ventricular outflow tract obstruction in hypertrophic cardiomyopathy.

AIMS: the geometry of the mitral apparatus changes dynamically throughout systole and diastole. We investigated how geometric dynamics of the mitral apparatus could affect the haemodynamics of the outflow tract in patients with hypertrophic cardiomyopathy presenting with systolic anterior motion (HCM(SAM)) using three-dimensional (3D) echocardiography. METHODS AND RESULTS: we obtained transthoracic volumetric images in 21 patients with HCM(SAM) with differing trans-left ventricular (LV) outflow tract pressure gradient (PG(LVOT)) and in 23 controls. Original software was used to crop the 3D data into 18 radial planes; the mitral annulus, leaflets, coaptation point, protruding septum, and papillary muscles (PMs) tips were traced in each plane. The data were then reconstructed for 3D distance measurements and volumetric assessment. Shorter coaptation-septal distance (12 ± 4 vs. 21 ± 3 mm, P 0.05). In addition, the coaptation-septal distance, TVindex, and inter-PM distance correlated each other (all P < 0.05). After adjustment for measures of mitral geometric change, the coaptation-septal distance was closely associated with PG(LVOT) (β = -0.73, P < 0.001). CONCLUSION: these findings suggest that dynamic geometric changes by interaction of PMs, mitral tenting, and the coaptation point at mid-systole may be important contributors to outflow obstruction in HCM(SAM).ope

Velocity-vector imaging을 이용한 대동맥 탄성의 정량화 및 조직학적 연관성

Dept. of Medicine/석사Backgrounds: The loss of aortic elasticity with aging, which impact on ventricular load and coronary perfusion is known to be strong determinant of cardiovascular events. Objectives: To determine the decisive method for quantification of aortic elastic properties with aging, we assessed the feasibility of a novel echo-tracking technique with velocity-vector imaging (VVI) and its correlation with tissue characterization.Methods: Fourteen mongrel dogs were classified with 7 young dogs (age 1 to 2 years, female, weighing 22 to 29kg) and 7 senescent dogs (age 8 to 11 years, female, weighing 36 to 45kg). Under general anesthesia, transesophageal echocardiography was performed to obtain the short-axis image of proximal descending thoracic aorta (DTA) for VVI analysis with identification of the location using fluoroscopic guidance. Then, the proximal DTA was excised to quantify tissue contents as collagen and elastin and assessed the correlation with the global and segmental aortic indices of elastic properties using VVI.Results: The mean aortic area was more dilated and fractional area change as global measure of VVI was significantly reduced in the senescent group than young group. When each aorta was divided into 6 segments, the segmental radial velocity (RV), circumferential strain and strain rate of VVI were also significantly reduced in the senescent group. For histologic correlation, RV and circumferential strain of VVI showed independent associations with the collagen contents of the corresponding segment of the DTA. Contrary to collagen content, mean or segmental content of elastin showed no significant correlations with any aortic indices of elastic properties.Conclusion: Alteration of aortic elastic properties with aging assessed by VVI was dilation and stiffening of aortic wall. VVI is a feasible, in vivo method for quantification of aortic elastic properties and the magnitude of VVI-derived parameters showed independent associations with tissue collagen content of vessel wall.restrictio

중국 대외원조의 양적 확대에 대한 분석: 1990년대 후반 이후 증가 사례를 중심으로

학위논문 (석사)-- 서울대학교 국제대학원 : 국제학과(국제지역학전공), 2013. 8. 조영남.본 논문은 1990년대 후반 이후 중국은 왜 대외원조 규모를 급격하게 증가시켰는가에 대한 실증 분석 연구이다. 21세기에 들어서면서 국제사회는 공적개발원조의 확대를 각국에 요청하였으며, 세계의 빈곤과 자연재해에 대한 공동의 책임을 전세계에 호소하고 있다. 중국의 경우 일견 신흥원조국으로서 이러한 호소에 동참하고 있는 것으로 보인다. 그러나 여타 공여국과 달리 중국의 경우 대외원조 정책 및 그 규모의 확대는 국제사회의 관심과 우려를 동시에 야기하고 있다. 왜냐하면 중국의 대외원조 정책은 일반 공여국에 비해 복합적이고 다층적인 전략적 수단으로 보이기 때문이다. 따라서 본 논문에서는 중국의 대외원조 정책의 확대를 다양한 각도에서 분석해 보고자 하였다. 기존에 중국의 대외원조가 에너지 부족을 해결하기 위한 자원외교로 사용되고 있다는 관점 이외에도, 외교적인 실리(대만 문제 등), 수출주도형 원조, FTA 등 여러 측면에서 접근하였고, 이에 대한 실증적인 데이터를 제시하고자 하였다. 또한 중국의 대외원조의 특성으로 중국과 선진원조국간의 원조 이념 및 정책적 차이를 비교함으로써 다양한 관점을 제공하려고 하였다. 이는 선진공여국 클럽에 가입하여 대외원조의 양적 확대와 더불어 대외원조정책의 선진화를 추구해야 하는 한국에게 있어 다양한 시각을 제공하고자 함이다. 마지막으로는 중국의 대외원조 공여액 추산 측면에서 광의의 원조와 협의의 원조로 분리하여 객관적인 지표를 제시하고자 하였다. 이는 중국이 대외원조 공여액을 공개하지 않기 때문에, 그 추정치의 오차가 매우 크며, 따라서 각종 데이터를 통해서 최대한 객관적인 수치를 제공하는데 목적을 두었다. 결론적으로는 중국의 대외원조는 국제적인 시각으로 보았을 때 적지 않은 문제점을 안고 있고 많은 부분 비판의 대상이 되고 있다. 이는 중국의 대외원조 정책 기조(基調)인 주권존중과 내정불간섭원칙으로 인해 수원국 선별에 있어서 국제원조질서에 부합되지 않는 형태로 이루어지며, 수원국의 개발이외에 자국의 실리주의를 위한 도구로 사용된다는 측면에서 기인한다. 그러나 중국이 대외원조를 통해서 자국에 가져다 준 이득은 적지 않은 것으로 생각되며, 이러한 성과를 기초로 하여 차후 대외원조 공여액은 더욱 증가할 것으로 생각된다. 따라서, 중국은 화평굴기를 실현하고, 중국의 꿈 꿈(中国夢)을 이루기 위해서는 대외원조 정책에서 義와 利 사이에서의 균형을 이룰 수 있어야 할 것이며, 이런 일련의 노력을 통해서 진정한 의미로서의 책임지는 강대국이 될 수 있을 것이다.The purpose of this paper is to demonstrate and analyze China having proliferated foreign aid policy since late 90s. It appears that China keeps pace with the global demand and request on official development assistance in jointly answering for poverty and natural disaster as one of the newly emerging donor countries. But the nations highly analytic approach, from time to time arousing concerns of the community of nations unlike any other donor countries of pure purpose, appears to exhibit the creature of strategic means with complexity. The goal of this paper is to perform multi-lateral analysis on Chinese foreign aid in that respect, not only from the established view that the nation takes it as a means of solution for the lasting problem of energy shortage but from the brand-new approaches that it is in search of the diplomatic benefit (against Taiwan, etc.), promotion of export-oriented industries and pan-global agreement such as FTA with appropriate data to back thereof. This paper also covers the analytic comparison of the principles and policies of aid between countries across the world China, in helping the country of Korea foray into global aid as a responsible member of the donor society. As for the estimating Chinese ODA, this paper took both broad and narrow senses of aid, in objectifying indexes to estimate the amount of Chinese aid politically kept in the dark. Though having been the target of criticism due to Non-intervention Principle in assessing the target of aid from time to time varied in contrast to the international standard, the highly strategic foreign aid from Chinese government may beef itself up with by way of tactic gains. To establish fairer balance between donors and donees benefit would thus be what matters here for the Asian giant to set itself, in the true sense of the word, Responsible Superpower by way of the peaceful rising.Ⅰ. Introduction ……….....................................................................1 1. Research Background and Research Question ………………..1 2. Literature Review ……………………………………………..2 3. Significance of the Study ……………………………………...4 4. Research Methodology and Statement ………………………..5 Ⅱ. Chinas Foreign aid since 1990 ………………………………....6 1. Chinas foreign aid Breakdown ……………………………….6 (1) China foreign aid Breakdown in a Broad Sense …………..7 (2) Chinas foreign aid Breakdown in a Narrow Sense ……....10 Ⅲ. Ground for Expanding Foreign Aid …….................................17 1. Chinese Foreign Aid: Feature ………………………………..20 2. Chinese Ground of Foreign Aid Policies …………………….25 (1) Securing Natural Resources ….………………………..…26 1) Geographic Property for Securing Natural Resources ……………………………………………………..…….30 A. Aid to African Countries ………………………..31 B. Aid to Asian Countries ………………………….41 (2) Holding Priority in Taiwan / Human Rights Issues ………50 1) Taiwan Issue …………………………………………….50 2) Human Right Issue …………………………………… 54 (3) Economic Side: Realization of Go Out Policy and Conclusion of FTA ……………………………………….57 1) Realization of Go Out Policy …………………..……57 2) Conclusion of FTA ………………………………..…61 (4) Improving Reputation by way of Soft Power …..……….69 Ⅳ. Effect of Chinas foreign aid…………………………………...72 (1) Economic Effect of Chinas foreign aid …………...…..73 1) Securing Natural Resources ...…………………………..73 2) Promotion of Trade and Investment …………………….77 (2) Soft Power Effect of Chinas foreign aid ……...…….…..81 Ⅴ. Conclusion: Signification of Chinas Foreign aid Policy ……86 Bibliography…………………………………………...………………………………..88 Abstract (Korean) ………………………………………………………………….…92Maste

Changes in availability and chemical forms of phosphorus accumulated in soils under cropping condition

학위논문(박사)--서울대학교 대학원 :농화학과,1999.Docto

Efficacy and safety profiles of a new S(-)-amlodipine nicotinate formulation versus racemic amlodipine besylate in adult Korean patients with mild to moderate hypertension: an 8-week, multicenter, randomized, double-blind, double-dummy, parallel-group, phase III, noninferiority clinical trial

BACKGROUND: "Chiral switching" from an existing racemate to a pure enantiomeric compound is a popular theme in drug development, especially when the enantiomer is found to have better efficacy and safety profiles. Amlodipine is a racemic mixture, composed of the S(-)-enantiomer, which is the pharmacologically active isomer, and the R(+)-enantiomer, which is 1000-fold less active. S(-)-amlodipine nicotinate, a chirally switched form of amlodipine nicotinate, has been developed and found to be bioequivalent to amlodipine besylate in Phase I clinical trials in Korea. OBJECTIVE: The aim of this study was to compare the efficacy and safety profiles of S(-)-amlodipine nicotinate with those of amlodipine besylate in adult Korean patients with mild to moderate hypertension (diastolic blood pressure [DBP] >or=90 mm Hg and <or=109 mm Hg). METHODS: This was an 8-week, multicenter, randomized, double-blind, double-dummy, parallel-group, Phase III, noninferiority clinical trial. After an initial 2-week placebo run-in period, patients aged 18 to 75 years with sitting DBP (SiDBP) >or=90 and or=90 mm Hg). The primary end point was noninferiority of the difference in mean SiDBP from baseline to week 8 for S(-)-amlodipine nicotinate compared with amlodipine besylate. Secondary end points were as follows: (1) noninferiority of the difference in mean sitting systolic blood pressure (SiSBP) from baseline to week 8 between the study groups; and (2) SiDBP response rate (defined as the proportion of patients whose SiDBP was or=10 mm Hg from baseline) after the 8-week treatment. Also, the incidence and severity of adverse events (AEs) and adverse drug reactions (ADRs) were reported. Severe AEs/ADRs were defined as those associated with any of the following: death; an event associated with a high risk of mortality; an event requiring hospitalization; or development of a permanent disability or congenital malformation. RESULTS: One hundred fifty-seven patients were assessed for inclusion in the study. of these, 124 patients were randomly allocated to receive S(-)-amlodipine nicotinate (42 men, 21 women; mean [SD] age, 52.4 [10.3] years [range, 23-70 years]; weight, 67.7 [10.8] kg [range, 44-92 kg]) or amlodipine besylate (45 men, 16 women; mean [SD] age, 54.5 [10.0] years [range, 30-73]; weight, 68.9 [9.8] kg [range, 49-95 kg]). One hundred sixteen patients completed the study, but 11 patients (8.9%) were dropped from the per-protocol analysis due to violations; therefore, 105 patients were included in the modified intent-to-treat population analysis (S[-]-amlodipine nicotinate, 55 patients; amlodipine besylate, 50 patients). There were no significant between-group differences in the baseline characteristics. Baseline mean (SD) SiSBP and SiDBP were 142.6 (11.3) and 94.9 (4.8) mm Hg in the S(-)-amlodipine nicotinate group, and 141.8 (8.3) and 96.1 (4.9) mm Hg in the amlodipine besylate group. Mean (SD) changes in SiSBP were 17.6 (11.2) mm Hg in the S(-)-amlodipine nicotinate group and 18.6 (12.3) mm Hg in the amlodipine besylate group. The SiDBP response rates were 92.7% in the S(-)-amlodipine nicotinate group and 88.0% in the amlodipine besylate group. There were no significant between-group differences in the prevalence of AEs and ADRs. In the S(-)-amlodipine nicotinate group, 15 patients (23.8%) reported a total of 28 AEs, and 19 patients (31.1%) reported a total of 27 AEs in the amlodipine besylate group. Six patients (9.5%) in the S(-)-amlodipine nicotinate group and 7 patients (11.4%) in the amlodipine besylate group experienced a total of 19 ADRs (11 and 8, respectively). The most common ADRs were liver enzyme elevation (3/63 [4.8%]) in the S(-)-amlodipine nicotinate group and facial flushing (3/61 [4.9%]) in the amlodipine besylate group. No cases of severe AEs or ADRs were reported in either group. CONCLUSIONS: The reduction of SiDBP after 8 weeks of treatment with S(-)-amlodipine nicotinate was noninferior compared with that of racemic amlodipine besylate in these adult Korean patients with mild to moderate hypertension. The SiDBP response rate and the reduction of SiSBP after 8 weeks of treatment with S(-)-amlodipine nicotinate were not significantly different from those with racemic amlodipine besylate. Both treatments were generally well tolerated.ope

Clinical outcomes of exercise-induced pulmonary hypertension in subjects with preserved left ventricular ejection fraction: implication of an increase in left ventricular filling pressure during exercise

OBJECTIVE: To investigate clinical outcomes of exercise-induced pulmonary hypertension (PH) and implications of an increase in left ventricular (LV) filling pressure during exercise in subjects with preserved LV ejection fraction. DESIGN: Longitudinal follow-up study. SETTING: Subjects who were referred for diastolic stress echocardiography. PATIENTS AND METHODS: The ratio of transmitral and annular velocities (E/Ea) and pulmonary artery systolic pressure (PASP) at rest and during exercise were measured in 498 subjects (57±11 years; 201 male). Exercise-induced PH was defined as present if PASP ≥50 mm Hg at 50 W of exercise, and an increase in LV filling pressure during exercise was present if E/Ea ≥15 at 50 W. MAIN OUTCOME MEASURES: A combination of major cardiovascular events and any cause of death. RESULTS: During a median follow-up of 41 months, there were 14 hospitalisations and four deaths. Subjects with exercise-induced PH had significantly worse clinical outcomes than those without (p=0.014). Subjects with exercise-induced PH associated with an increase in E/Ea during exercise had significantly worse outcomes than other groups (p<0.001). However, prognosis was similar between subjects with exercise-induced PH without an increase in E/Ea and those without exercise-induced PH. In subjects with exercise-induced PH, E/Ea at 50 W was an independent predictor of adverse outcomes (HR 1.37; 95% CI 1.02 to 1.83; p=0.036). CONCLUSIONS: Exercise-induced PH provides prognostic information in subjects with preserved LV ejection fraction. The excess risk of exercise-induced PH is restricted to subjects with an increase in estimated LV filling pressure during exercise.ope

Impact of left ventricular longitudinal diastolic functional reserve on clinical outcome in patients with type 2 diabetes mellitus

BACKGROUND: Left ventricular longitudinal diastolic functional reserve (DFR), as assessed by the change in early diastolic mitral annular velocity (E') during exercise, is abnormal in patients with type 2 diabetes mellitus (DM). However, the impact of left ventricular longitudinal DFR on clinical outcome has not been explored. This study evaluated the incremental prognostic value of left ventricular DFR in patients with type 2 DM without overt heart disease. METHODS: Of 1485 patients who were referred for exercise stress echocardiography, 197 consecutive patients (mean age, 58 years; 84 men) with type 2 DM without overt heart disease were identified. Left ventricular longitudinal DFR was defined as the change in E' from resting to exercise (ΔE'). The endpoint was a composite of death and hospitalisation for heart failure (HF). RESULTS: During a median follow-up of 57 months (range 6-90), 18 of 197 patients (9.1%) had adverse events (12 deaths, six hospitalisations for HF). Independent predictors of adverse events in a Cox regression analysis were estimated glomerular filtration rate (HR 0.97; 95% CI 0.95 to 0.98; p<0.001), DM duration (HR 1.07; 95% CI 1.01 to 1.14; p=0.018) and ΔE' (HR 0.58; 95% CI 0.40 to 0.85; p=0.005). In an incremental model, the addition of stress echo data significantly increased the χ² of the clinical and resting left ventricular function model, from 40.5 to 46.6 (p=0.005). CONCLUSION: Assessment of left ventricular longitudinal DFR during exercise provided incremental prognostic information in patients with type 2 DM without overt heart disease.ope

Value of ventricular stiffness index and ventriculoarterial interaction in patients with nonischemic dilated cardiomyopathy

BACKGROUND: Whether echo-Doppler-derived index of ventricular elastance or ventriculoarterial interaction can reliably reflect circulatory efficiency in various conditions was investigated in the present study and whether they can be helpful in predicting exercise capacity in patients with dilated cardiomyopathy (DCM). METHODS AND RESULTS: The 25 patients with DCM, 25 age- and gender-matched hypertensive patients, and 25 marathon runners underwent symptom-limited graded supine bicycle exercise echocardiography after resting echo-Doppler evaluation. Echo-Doppler-derived left ventricular (LV) diastolic elastance index (Ed), ventricular-vascular coupling index (10 x Ea/Ees), based on arterial elastance index (Ea) to LV end-systolic elastance index (Ees), and hemodynamic parameters were measured during rest and exercise. DCM patients had lower Ees, higher Ed and Ea/Ees with blunted exercise responses of Ees than the other groups, and the hypertensive patients had lower Ees and DeltaEes compared with the marathon runners. Resting Ed, Ea/Ees, and total stiffness index (10 x Ed x Ea/Ees) correlated with exercise duration independent of age and gender. A stiffness index of 0.8 could reliably predict impaired exercise capacity. CONCLUSIONS: Echo-derived elastance is predictive of exercise capacity in patients with DCMope