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Kim YM, Yoo SJ, Kim TH, Park IS, Kim WH, Kim SH, Lee YT. Tracheal compression by elongated aortic arch in patients with congenitally corrected transposition of the great arteries. Pediatr Cardiol 2001; 22:471-7. [PMID: 11894148 DOI: 10.1007/s002460010277] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
We investigate the tracheal compression by aortic arch in patients with congenitally corrected transposition of the great arteries. Fourteen patients whose ascending aorta was connected to descending aorta on the contralateral side were divided into two groups according to the severity of tracheal compression on lateral angiogram: group 1 (stenosis > or = 50%, eight patients) and group 2 (stenosis < 50%, six patients). We compared the following variables between the groups: aortic size, lateral displacement of ascending aorta, retrosternal space, and contour of aortic arch. Spiral computed tomography (CT) was done in five patients of group 1. The ratio between measured and normal diameters of ascending aorta of group 1 was significantly larger than that of group 2 (1.57 +/- 0.14 compared to 1.19 +/- 0.26, p = 0.014). There was linear correlation between the tracheal compression and aortic size (r = 0.69, p = 0.001). The ascending aorta was positioned more laterally and the aortic arch was located more posteriorly in group 1. In four patients with decreased tracheal compression after surgery, aortic size decreased and the ascending aorta restored its anterior position. Spiral CT showed transversely oriented aortic arch and severe tracheal compression in the anteroposterior direction by aortic arch. The tracheal compression by aortic arch in corrected transposition is common when the descending aorta is located on the contralateral side of the ascending aorta. Aortic size, posterior position, elongation, and end-on appearance of the aortic arch are the useful predictors of tracheal compression.
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Lin LY, Wu CC, Liu YB, Ho YL, Liau CS, Lee YT. Derangement of heart rate variability during a catastrophic earthquake: a possible mechanism for increased heart attacks. Pacing Clin Electrophysiol 2001; 24:1596-601. [PMID: 11816627 DOI: 10.1046/j.1460-9592.2001.01596.x] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
At 1:47 AM on September 21, 1999, the middle part of Taiwan was struck by a major earthquake measuring 7.3 on the Richter scale. It has been shown that the mental stress caused by an earthquake could lead to a short- or long-term increase in frequency of cardiac death probably through activation of the sympathetic nervous system. The aim of this study was to investigate the effects of emotional stress on the autonomic system during an actual earthquake. Fifteen patients receiving a 24-hour Holter ECG study starting from 10+/-4 hours before the onset of the earthquake were included for the analysis of time- and frequency-domains of heart rate variability (HRV) at several time periods. A 24-hour Holter study recorded 2-6 months before the earthquake in 30 age- and sex-matched subjects served as the control group. Heart rate and the low frequency (LF) to high frequency (HF) ratio increased significantly after the earthquake and were attributed mainly to the withdrawal of the high frequency component (parasympathetic activity) of HRV. Sympathetic activation was blunted in elderly subjects > 60 years old. The concomitant ST-T depression observed in the Holter study correlated with a higher increment of LF as compared to HF components. The changes observed in HRV recovered completely 40 minutes following the earthquake. The derangement of HRV results from the withdrawal of the parasympathetic component and the arousal of sympathetic activity by the stressful earthquake. However, this autonomic derangement returned towards normal 40 minutes following the earthquake.
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Lee TM, Su SF, Hwang JJ, Tseng CD, Chen MF, Lee YT, Wang SS. Differential lipogenic effects of cilostazol and pentoxifylline in patients with intermittent claudication: potential role for interleukin-6. Atherosclerosis 2001; 158:471-6. [PMID: 11583728 DOI: 10.1016/s0021-9150(01)00457-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Cilostazol, a novel oral phosphodiesterase inhibitor, has shown consistent improvement in exercise tolerance in patients with intermittent claudication (IC). In addition to this effect, cilostazol has previously been shown to have beneficial effects on the dyslipidemia, i.e., combination of high triglycerides with low high-density-lipoprotein cholesterol (HDL-C) levels. Interleukin-6 (IL-6) suppresses the activity of lipoprotein lipase, which modulates the metabolism of triglycerides and HDL-C. To determine whether a reduction of IL-6 contributes to the improvement of lipid profiles, we prospectively investigated the effect of cilostazol (n=16, 100 mg, twice daily) on the changes of lipid profiles and on the association with the changes of IL-6 compared with those of pentoxifylline (n=16, 400 mg, bid) in patients with IC. After eight weeks of administration of cilostazol to patients with IC, walking distances were increased, associated with a 29% decrease in plasma triglycerides and a 13% increase in HDL-C. No significant changes of lipid profiles in the pentoxifylline and placebo groups were observed although a similar improvement in walking distances was achieved in the pentoxifylline group. IL-6 levels were significantly reduced in patients receiving cilostazol as compared with those receiving placebo or pentoxifylline. The cilostazol-induced changes in the IL-6 were positively related to those of triglycerides in the cilostazol group (r=0.63, P<0.05) and negatively related to those of HDL-C (r=-0.55, P<0.05). These findings suggest that in addition to consistent improvement of exercise tolerance, cilostazol may improve lipid profiles by reducing IL-6 release. However, pentoxifylline did not affect lipid profiles although a similar improvement of maximal walking distance (MWD) was achieved.
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Wang TD, Chen WJ, Chien KL, Seh-Yi Su SS, Hsu HC, Chen MF, Liau CS, Lee YT. Efficacy of cholesterol levels and ratios in predicting future coronary heart disease in a Chinese population. Am J Cardiol 2001; 88:737-43. [PMID: 11589839 DOI: 10.1016/s0002-9149(01)01843-4] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
In this study, we assessed the efficacy of various lipid and lipoprotein measurements at baseline for predicting the risk for coronary heart disease (CHD) and determined the associated risk of CHD in subgroups stratified by different lipid and lipoprotein screening strategies to evaluate the adequacy of current total and low-density lipoprotein (LDL) cholesterol-based approaches in lipid management. We analyzed data from the Chin-Shan Community Cardiovascular Cohort study, a Chinese population-based prospective cohort study that began in 1990. During an 8-year follow-up period, 213 of 3,159 participants (6.7%) without CHD (aged > or =35 years) developed CHD. The total cholesterol/high-density lipoprotein (HDL) cholesterol ratio was the most powerful lipoprotein predictor of future CHD (hazard ratio 1.21 for a 1.0 increment in ratio; p <0.001). Subjects with "high-risk" LDL cholesterol levels (>160 mg/dl) and low total cholesterol/HDL cholesterol ratios (< or =5) had an incidence of CHD similar to those with low levels of both LDL cholesterol (< or =130 mg/dl) and total cholesterol/HDL cholesterol ratios (4.9% vs 4.6%). In contrast, subjects with "low-risk" LDL cholesterol levels (< or =130 mg/dl) and high total cholesterol/HDL cholesterol ratios (>5) had a 2.5-fold higher incidence of CHD than those with similar LDL cholesterol levels but low total cholesterol/HDL cholesterol ratios (p <0.001). Compared with using an LDL cholesterol level of 130 mg/dl as the cut-off point, using a total cholesterol/HDL cholesterol ratio of 5 was associated with superior specificity (73% vs 59%, p <0.001) and accuracy (72% vs 58%, p <0.001), and similar sensitivity (50% vs 53%). Our data indicate that current guidelines for lipid management may misclassify subjects with high levels of HDL and LDL cholesterol as well as those with low levels of HDL and LDL cholesterol. Using the ratio of total to HDL cholesterol as the initial screening tool can obviate this discrepancy.
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Su TC, Jeng JS, Chien KL, Sung FC, Hsu HC, Lee YT. Hypertension status is the major determinant of carotid atherosclerosis: a community-based study in Taiwan. Stroke 2001; 32:2265-71. [PMID: 11588311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
BACKGROUND AND PURPOSE Extracranial carotid artery (ECCA) atherosclerosis has been associated with hypertension-related stroke. The present study was aimed at investigating the determinants of ECCA atherosclerosis in patients with hypertension in Taiwan. METHODS The extent and severity of ECCA atherosclerosis were measured by high-resolution B-mode ultrasonography and expressed as maximal intima-media thickness (IMT) of the common carotid artery, ECCA plaque score, and carotid stenosis >/=50%. From July through December 1996, 263 hypertensive patients (146 with hypertension and 117 with borderline hypertension) and 270 normotensive adults from the Chin-Shan Community Cardiovascular Cohort participated in this study. Risk factors and ECCA atherosclerosis were stratified by the blood pressure status. RESULTS A significant dose-response relationship was found between the status of hypertension and the severity of carotid atherosclerosis. Multivariate logistic regression models revealed that hypertension (including borderline), male gender, smoking, and age >/=65 years significantly increased the risk of thicker IMT. The risk of ECCA plaque score >6 increased significantly in conjunction with hypertension, age >/=65 years, left ventricular hypertrophy on ECG, and smoking. However, hypertension and smoking were the 2 evident determinants of carotid stenosis >/=50% after adjustment for other covariates. Compared with the normotensive subjects, the ORs (and 95% CIs) for the hypertensive patients to develop carotid atherosclerosis were 5.0 (3.0 to 8.4) indexed by maximal common carotid artery IMT >/=75th percentile, 3.7 (1.8 to 7.9) by ECCA score >6, and 4.8 (1.4 to 16.5) by carotid stenosis >/=50%. CONCLUSIONS Hypertension strongly influence carotid atherosclerosis. Our findings reinforce the hypothesis that hypertension has a major role in the pathogenesis of atherosclerosis.
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Lee YT, Miller LD, Gubin AN, Makhlouf F, Wojda U, Barrett AJ, Liu ET, Miller JL. Transcription patterning of uncoupled proliferation and differentiation in myelodysplastic bone marrow with erythroid-focused arrays. Blood 2001; 98:1914-21. [PMID: 11535529 DOI: 10.1182/blood.v98.6.1914] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Because abnormal erythroid differentiation is the most common manifestation of the myelodysplastic syndromes (MDS), it was hypothesized that erythroid gene expression may be used to illustrate myelodysplastic transcription patterns. Ten normal bone marrow aspirates (NBM) were first analyzed using an erythroid-focused cDNA array to define steady-state transcription levels. Proliferation and differentiation gene subsets were identified by statistically significant differences between NBM and erythroleukemia gene expression. Next, cDNAs from 5 separate MDS aspirates were studied: refractory anemia, refractory anemia with ringed sideroblasts, refractory anemia with excess blasts, refractory anemia with excess blasts in transformation (RAEB-T), and RAEB-T/secondary MDS. A distinct pattern of significantly increased proliferation-associated and reduced differentiation-associated gene activity was established for MDS.
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Hsu HC, Lee YT, Chen MF. Effects of fish oil and vitamin E on the antioxidant defense system in diet-induced hypercholesterolemic rabbits. Prostaglandins Other Lipid Mediat 2001; 66:99-108. [PMID: 11529555 DOI: 10.1016/s0090-6980(01)00146-0] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
This study was designed to investigate the effects of fish oil and vitamin E on the antioxidant defense system in hypercholesterolemic rabbits. A high fat and cholesterol diet, with or without supplement by fish oil and/or a vitamin E supplement, was fed to rabbits for 6 weeks. Compared to the reference diet of regular laboratory rabbit chow, a high fat and cholesterol-enriched diet increased atheroma formation, plasma lipid and peroxide levels, decreased blood glutathione levels, and reduced plasma glutathione reductase, glutathione peroxidase, and catalase activities. Fish oil supplementation significantly reduced atheroma and increased glutathione reductase and glutathione peroxidase activities and blood glutathione levels, but increased plasma lipid peroxide levels. Vitamin E supplementation of the fish oil diet enhanced the beneficial effects by increasing glutathione reductase activity and decreasing peroxide levels. These results indicate that a high fat and cholesterol diet attenuates blood glutathione levels and plasma antioxidant enzyme activities, which may account for some of its atherogenic properties. Consumption of fish oil enhances antioxidative defenses against the oxidative stress imposed by hypercholesterolemia, and vitamin E further enhances these beneficial effects.
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Chien KL, Hsu HC, Su TC, Hwang YL, Chang WT, Sung FC, Lin RS, Lee YT. Components of insulin resistance syndrome in a community-based population assessed by log-linear models. J Formos Med Assoc 2001; 100:587-91. [PMID: 11695272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2023] Open
Abstract
BACKGROUND AND PURPOSE To investigate the clustering of insulin resistance syndrome with hyperinsulinemia, hypertriglyceridemia, low high-density lipoprotein (HDL) cholesterol, hypertension, and obesity, we conducted this cross-sectional study and analyzed the patterns of conditional independence among these five elements. METHODS Fasting insulin, lipid profiles, blood pressure, and anthropometric data from 2165 Taiwanese older than 35 years in the Chin-Shan community were examined. The cut-off points of these five factors (all binary variables) were defined. The hierarchical log-linear regression with nested effects model was applied to fit this higher-order contingency table of five variables, and likelihood ratio (chi2) statistics were used to test the goodness of fit. RESULTS Hyperinsulinemia was independently correlated with obesity (odds ratio [OR] 5.7, 95% confidence interval [CI] 4.5-7.3), low HDL (OR 2.3, 95% CI 1.8-2.9), and hypertriglyceridemia (OR 1.6, 95% CI 1.2-2.2). Hypertriglyceridemia was significantly associated with low HDL (OR 3.6, 95% CI 2.7-4.8), and non-significantly associated with hypertension (OR 1.3, 95% CI 0.9-1.7) and obesity (OR 1.1, 95% CI 0.8-1.6). In persons with normal triglyceride levels, hypertension was positively associated with obesity (OR 2.8, 95% CI 2.1-3.7) and low HDL (OR 2.0, 95% CI 1.5-2.8). Analyses from forward and backward selection methods gave similar results. Graphical models with conditional independence relationships among these five variables were demonstrated. CONCLUSIONS The components of insulin resistance syndrome have intricate relationships. Hyperinsulinemia was most related to obesity, and hypertriglyceridemia was most related to low HDL.
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Lee TM, Su SF, Tsai CH, Lee YT, Wang SS. Differential effects of cilostazol and pentoxifylline on vascular endothelial growth factor in patients with intermittent claudication. Clin Sci (Lond) 2001; 101:305-11. [PMID: 11524048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
Cilostazol is a new phosphodiesterase inhibitor with anti-platelet and vasodilatory properties. Cilostazol and pentoxifylline are the only two drugs that have been approved for the treatment of patients with intermittent claudication. However, the mechanisms by which exercise tolerance is improved remain unclear. Vascular endothelial growth factor (VEGF) is a potent endothelial mitogen that results in angiogenesis when overexpressed in human subjects. To assess the potential role of VEGF in the improvement in exercise tolerance, we investigated plasma levels of VEGF in 50 patients with intermittent claudication who were allocated randomly to groups receiving cilostazol (n=17), pentoxifylline (n=17) or placebo (n=16). Patients given either cilostazol or pentoxifylline showed a significant improvements in maximal walking distance compared with the placebo group (34 m and 33 m respectively, compared with 5 m; both P<0.05). Neither cilostazol nor pentoxifylline increased the ankle-brachial index after treatment. Circulating VEGF levels were increased (from 116+/-29 to 169+/-45 pg/ml; P=0.002), and the levels of VEGF were correlated significantly with exercise tolerance in a positive direction (r=0.88, P=0.004), in those patients treated with cilostazol that did not have diabetes mellitus. In contrast, VEGF levels remained stable after the administration of pentoxifylline. These findings suggest that VEGF may contribute to the cilostazol-related improvement in exercise tolerance in non-diabetic patients. However, pentoxifylline did not affect VEGF levels, although a similar improvement in maximal walking distance was achieved. Thus the mechanisms involved in the pentoxifylline-treated group were different from those in the cilostazol-treated group, and require further study.
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Huang CH, Chen WJ, Ma MH, Lai CL, Lin FY, Lee YT. Ambulance utilization in metropolitan and rural areas in Taiwan. J Formos Med Assoc 2001; 100:581-6. [PMID: 11695271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2023] Open
Abstract
BACKGROUND AND PURPOSE Emergency medical services (EMS) have expanded rapidly in the Asian developing countries recently. However, the patterns of ambulance utilization in the rural and urban areas of these countries have not been thoroughly described. This study investigated the patterns of ambulance utilization in two urban areas and the larger rural area of Taiwan formerly designated Taiwan Province. METHODS We studied a total of 304,368 ambulance missions during 1997 in Taiwan. We analyzed the differences in the characteristics of emergency calls and the interventions performed on the scene in two urban areas, Taipei City and Kaohsiung City, and in the rural area formerly designated Taiwan Province. RESULTS The call volume and percentage of non-transport calls were higher in the more developed of the two urban areas, Taipei City, than in Kaohsiung (p < 0.01). The incidence of calls with trauma-related causes was higher in both urban areas. However, the percentage of calls placed for trauma-related reasons was higher in the rural area (p < 0.01). More calls for acute medical illness were placed in Taipei City (p < 0.01) than in the rural area. The number of interventions performed by ambulance staff was higher in Taipei City and Kaohsiung City than in the rural area (p < 0.01). The availability of acute illness management was generally lower than needed in all areas. CONCLUSIONS Call volume and the number of interventions performed were higher in the urban area, whereas the percentage of trauma-related calls was higher in the rural area. These findings suggest that EMS use patterns in Taiwan are transitioning towards a pattern characteristic of a more developed country. The differences in ambulance utilization patterns must be considered in plans to further develop EMS services in these areas.
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Lin LC, Kao HL, Wu CC, Ho YL, Lee YT. Alterations of myocardial ultrasonic tissue characterization by coronary angioplasty in patients with chronic stable coronary artery disease. ULTRASOUND IN MEDICINE & BIOLOGY 2001; 27:1191-1198. [PMID: 11597359 DOI: 10.1016/s0301-5629(01)00422-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
We conducted a study to delineate the alterations in the cyclic changes of myocardial ultrasonic integrated backscatter (IBS) in patients receiving angioplasty for chronic coronary artery disease. Ultrasonic tissue characterization (UTC) and dobutamine stress echocardiography were performed in 43 patients before and 24 h after angioplasty, as well as before the follow-up angiography 3 months later. For segments being normokinetic with ischemic burden, the blunted amplitude and increased nadir deviation of IBS cyclic modulation recovered soon after angioplasty. For dyssynergic segments with contractile reserve, the angioplasty rebuilt the amplitude before the wall motion recovered, but corrected the nadir deviation tardily. In both circumstances, the coronary restenosis abolished the initial restoration. Those nonviable segments persistently revealed large deviations and small weighted amplitudes irrelevant to coronary lesions. The progress of myocardial ischemia, the development of wall motion dyssynergy and, then, the loss of viability, show different patterns of alterations in UTC after alleviating coronary obstructions.
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Wang TD, Chen WJ, Su SS, Su TC, Chen MF, Liau CS, Lee YT. Increased levels of tissue plasminogen activator antigen and factor VIII activity in nonvalvular atrial fibrillation: relation to predictors of thromboembolism. J Cardiovasc Electrophysiol 2001; 12:877-84. [PMID: 11523531 DOI: 10.1046/j.1540-8167.2001.00877.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
INTRODUCTION Given that nonvalvular atrial fibrillation (AF)-associated stroke can be either cardioembolic or atherothrombotic, we investigated the relationships between nonvalvular AF and hemostatic factors reflecting intrinsic thrombogenic and atherogenic potentials (tissue plasminogen activator [t-PA] antigen, plasminogen activator inhibitor-1, and factor VIII activity). We also evaluated the clinical applicability of these hemostatic factors by examining whether AF subjects with established clinical or echocardiographic predictors of thromboembolism had higher levels of these factors. METHODS AND RESULTS Of the 3,212 participants of a Chinese population-based study, 53 subjects (1.7%) with AF were identified. Among the hemostatic factors measured, t-PA antigen (median 12.8 vs 8.1 ng/mL; P < 0.01) and factor VIII activity (median 155% vs 133%; P < 0.05) were significantly higher in AF subjects after adjustment for age and sex. In multivariate analysis, features independently associated with t-PA antigen levels were AF, sex, body mass index, systolic blood pressure, total cholesterol, triglycerides, and left ventricular systolic dysfunction. Features independently associated with factor VIII activity levels included AF, age, and total cholesterol. Levels of both t-PA antigen and factor VIII activity were primarily elevated in AF subjects with predictors of thromboembolism (age > 75 years, hypertension, diabetes, and left ventricular systolic dysfunction), whereas in AF subjects with no thromboembolic predictors, plasma levels of hemostatic factors examined were similar to those without AF. CONCLUSION We demonstrated that nonvalvular AF was independently associated with increased peripheral levels of t-PA antigen and factor VIII activity. Levels of both hemostatic factors were primarily elevated in AF subjects with predictors of thromboembolism. Whether these hemostatic factors are independently predictive of future thromboembolic events in AF patients requires further investigation.
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Chen MF, Wang TD, Yeh HT, Hsu HC, Lee YT. Gemfibrozil treatment potentiates oxidative resistance of high-density lipoprotein in hypertriglyceridemic patients. Eur J Clin Invest 2001; 31:707-13. [PMID: 11473572 DOI: 10.1046/j.1365-2362.2001.00868.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
BACKGROUND Studies suggest that both oxidized low and high density lipoprotein (LDL and HDL) play a role in the pathogenesis of atherosclerosis. Gemfibrozil is widely used and is reported to increase cholesterol of LDL and HDL in hypertriglyceridemic patients. The aim of this study was to investigate the effect of gemfibrozil treatment on the oxidative status of lipoprotein particles in Fredrickson phenotype IV hypertriglyceridemic patients. METHODS Twenty-two patients, aged 38-64 years, with fasting plasma triglyceride concentrations between 2.90 and 8.97 mmol L(-1), were recruited and were given gemfibrozil 300 mg three times daily for 12 weeks. Venous blood samples were collected before gemfibrozil treatment, after 4, 8, or 12 weeks of treatment, and 4 weeks after termination of treatment, and used to analyse the plasma lipid profile, isolate lipoproteins, and analyse the chemical composition and in vitro oxidation of lipoprotein particles. RESULTS Gemfibrozil treatment resulted in a decrease in plasma total triglyceride levels and the triglyceride content of all lipoproteins. Plasma total cholesterol levels were decreased as a result of a decrease in very low density lipoprotein (VLDL) cholesterol levels. A slight increase in LDL cholesterol levels was observed, whereas the thiobarbituric acid-reactive substances (TBARS) of LDL were decreased and the lag and peak time of LDL to oxidation were unchanged and maximal diene production was decreased. Plasma HDL cholesterol levels, the surface-to-core ratio of HDL particles, and the resistance of HDL to oxidation were increased. CONCLUSION The decreased TBARS and diene production of LDL, increased HDL cholesterol levels, and increased resistance of HDL to oxidation may, in part, explain why gemfibrozil treatment was found to be generally beneficial in terms of protection against coronary heart disease.
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Chang PY, Luo S, Jiang T, Lee YT, Lu SC, Henry PD, Chen CH. Oxidized low-density lipoprotein downregulates endothelial basic fibroblast growth factor through a pertussis toxin-sensitive G-protein pathway: mediator role of platelet-activating factor-like phospholipids. Circulation 2001; 104:588-93. [PMID: 11479258 DOI: 10.1161/hc3101.092213] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
BACKGROUND Oxidized LDL (oxLDL) inhibits angiogenesis in part by downregulating endothelial basic fibroblast growth factor (bFGF). To determine the mechanism of the downregulation, we investigated the signal transduction pathway involving potential phospholipid mediators. METHODS AND RESULTS Cultured bovine aortic endothelial cells were incubated with PBS (lipoprotein-free control), LDL, or copper oxLDL under serum-free conditions. At 24 hours, oxLDL (50 microg/mL) decreased bFGF mRNA (Northern blot), bFGF protein (Western blot and ELISA), and concomitant DNA synthesis, all by 40% to 50% compared with PBS. LDL had no effect. Pretreating the cells with 100 ng/mL pertussis toxin (PTX) for 18 hours before oxLDL exposure almost completely blocked the inhibitory effects of oxLDL. In contrast, inhibiting other major cellular signal transduction pathways with PD-98059 (mitogen-activated protein kinase kinase inhibitor), HA-1004 (inhibitor of cGMP- and cAMP-dependent protein kinase), or Ro-31-8220 (protein kinase C inhibitor) or chelating intracellular Ca(2+) with BAPTA-AM failed to attenuate any of the oxLDL effects assayed. Addition to the cultures of WEB 2086, a specific antagonist of the PTX-sensitive G protein-coupled platelet-activating factor (PAF) receptor, blocked the action of oxLDL. Whereas PAF dispersed in the culture medium failed to produce oxLDL-like effects, degradation of PAF and PAF-like phospholipids accumulated in oxLDL with a recombinant human PAF acetylhydrolase eliminated the inhibitory effects of oxLDL on bFGF expression and DNA synthesis. CONCLUSIONS OxLDL suppresses endothelial bFGF expression and DNA synthesis through a PTX-sensitive heterotrimeric G-protein pathway involving mediator phospholipids similar, but not identical, to PAF.
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MESH Headings
- 1-Alkyl-2-acetylglycerophosphocholine Esterase
- Animals
- Azepines/pharmacology
- Blotting, Northern
- Blotting, Western
- Calcium-Calmodulin-Dependent Protein Kinases/antagonists & inhibitors
- Cattle
- Cells, Cultured
- Chelating Agents/pharmacology
- Cyclic AMP-Dependent Protein Kinases/antagonists & inhibitors
- Down-Regulation
- Egtazic Acid/analogs & derivatives
- Egtazic Acid/pharmacology
- Endothelium, Vascular/drug effects
- Endothelium, Vascular/metabolism
- Enzyme Inhibitors/pharmacology
- Fibroblast Growth Factor 2/drug effects
- Fibroblast Growth Factor 2/genetics
- Fibroblast Growth Factor 2/metabolism
- Flavonoids/pharmacology
- GTP-Binding Proteins/metabolism
- Indoles/pharmacology
- Isoquinolines/pharmacology
- Lipoproteins, LDL/pharmacology
- Lipoproteins, LDL/physiology
- Pertussis Toxin
- Phospholipases A/pharmacology
- Platelet Activating Factor/physiology
- Protein Kinase C/antagonists & inhibitors
- RNA, Messenger/drug effects
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Recombinant Proteins/pharmacology
- Signal Transduction
- Sulfonamides
- Triazoles/pharmacology
- Virulence Factors, Bordetella/pharmacology
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Lee YT, Duggleby RG. Identification of the regulatory subunit of Arabidopsis thaliana acetohydroxyacid synthase and reconstitution with its catalytic subunit. Biochemistry 2001; 40:6836-44. [PMID: 11389597 DOI: 10.1021/bi002775q] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Acetohydroxyacid synthase (EC 4.1.3.18; AHAS) catalyzes the initial step in the formation of the branched-chain amino acids. The enzyme from most bacteria is composed of a catalytic subunit, and a smaller regulatory subunit that is required for full activity and for sensitivity to feedback regulation by valine. A similar arrangement was demonstrated recently for yeast AHAS, and a putative regulatory subunit of tobacco AHAS has also been reported. In this latter case, the enzyme reconstituted from its purified subunits remained insensitive to feedback inhibition, unlike the enzyme extracted from native plant sources. Here we have cloned, expressed in Escherichia coli, and purified the AHAS regulatory subunit of Arabidopsis thaliana. Combining the protein with the purified A. thaliana catalytic subunit results in an activity stimulation that is sensitive to inhibition by valine, leucine, and isoleucine. Moreover, there is a strong synergy between the effects of leucine and valine, which closely mimics the properties of the native enzyme. The regulatory subunit contains a sequence repeat of approximately 180 residues, and we suggest that one repeat binds leucine while the second binds valine or isoleucine. This proposal is supported by reconstitution studies of the individual repeats, which were also cloned, expressed, and purified. The structure and properties of the regulatory subunit are reminiscent of the regulatory domain of threonine deaminase (EC 4.2.1.16), and it is suggested that the two proteins are evolutionarily related.
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Chan SL, Lee YT, Chan YC, Au YK, Yeung VT. A young male patient with persistent fever due to tuberculous peritonitis. Hong Kong Med J 2001; 7:209-12. [PMID: 11514760] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023] Open
Abstract
Tuberculous peritonitis is an uncommon disease in Hong Kong. We report a case of tuberculous peritonitis in a young male. The patient presented with persistent fever and intermittent cough for 1 month, but had no gastrointestinal symptoms. It was only through detection of slight abdominal ascites that subsequent abdominal paracentesis and laparoscopic biopsy confirmed the diagnosis. Appropriate antituberculous treatment was prescribed. Progress was complicated by persistent fever and liver function derangement, successfully managed by careful titration of antituberculous medications.
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Wu JH, Lee YT, Hsu HC, Hsieh LL, Wen MS, Chern MS, Wu D. Further characterization of apolipoprotein B genetic variations in Taiwanese. Hum Biol 2001; 73:451-60. [PMID: 11459425 DOI: 10.1353/hub.2001.0044] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Apolipoprotein B (apoB, protein; APOB, gene) is the main protein component of low-density lipoprotein (LDL) and plays an important role in blood lipid metabolism. Previously, we have reported four APOB coding regions, 5' signal peptide, and 3' repeat sequence polymorphisms in our population. In this report, we further characterize other APOB genetic variations. The results illustrate that the mutation frequencies for Arg3500Gln (1/846 alleles), Arg4019Trp (2/786 alleles), -265 C/T promoter region (0/264 alleles), and intron 2 A/G (0/450 alleles) are very low. Our population showed a frequency of 68.9% for the B4311 Ser allele. The B4311 Asn allele was associated with a higher apoB level than the Ser group (p < 0.05) in normal controls. In the normal controls, a higher B4311 Asn/Asn genotype frequency was found in the group with total cholesterol (TC) > 200 mg/dL and apoB concentration > 85 mg/dL than in the group with a TC < 200 mg/dL and apoB < 85 mg/dL (p = 0.03 for TC comparison).
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Hsu HC, Lee YT, Yeh HT, Chen MF. Effect of gemfibrozil on the composition and oxidation properties of very-low-density lipoprotein and high-density lipoprotein in patients with hypertriglyceridemia. THE JOURNAL OF LABORATORY AND CLINICAL MEDICINE 2001; 137:414-21. [PMID: 11385362 DOI: 10.1067/mlc.2001.114991] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Recent studies suggest that both oxidized very-low-density lipoprotein (VLDL) and oxidized high-density lipoprotein (HDL) may play a role in the pathogenesis of atherosclerosis. Gemfibrozil is widely used and is reported to decrease VLDL levels and increase HDL levels. The aim of this study was to investigate the effect of gemfibrozil on the chemical composition and oxidative susceptibility of VLDL and HDL and their relationship with atherosclerosis. Twenty patients with hypertriglyceridemia were treated with 300 mg gemfibrozil, 3 times daily, for 12 weeks. Venous blood samples were collected before treatment, at the end of treatment, and 4 weeks after the end of treatment. Gemfibrozil effectively lowered concentrations of plasma lipid, apolipoprotein (apo) B, and apo E. The lipid and protein content of VLDL were also decreased, but not by the same extent. The surface-to-core ratio and apo E/apo B ratio of VLDL particles were increased after gemfibrozil treatment. HDL(2) cholesteryl ester and HDL(3) apo A-II content were also increased. Gemfibrozil treatment lowered levels of lipid peroxides in both VLDL and HDL particles. The susceptibility of VLDL to oxidation was unchanged, whereas maximal peroxide production was decreased. The oxidative susceptibility of both HDL(2) and HDL(3) decreased with gemfibrozil treatment. These results indicate that after gemfibrozil treatment, VLDL and HDL particles in patients with hypertriglyceridemia are less atherogenic, which may explain why gemfibrozil treatment is beneficial in terms of coronary heart disease in hypertriglyceridemia.
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Park SI, Park EJ, Kim NH, Baek WK, Lee YT, Lee CJ, Suh CK. Hypoxia delays the intracellular Ca2+ clearance by Na+-Ca2+ exchanger in human adult cardiac myocytes. Yonsei Med J 2001; 42:333-7. [PMID: 11456400 DOI: 10.3349/ymj.2001.42.3.333] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Transient myocardial ischemia during cardiac surgery causes a loss of energy sources, contractile depression, and accumulation of metabolites and H+ ion resulting in intracellular acidosis. The reperfusion following ischemic cardioplegia recovers intracellular pH, activates Na+-H+ exchange and Na+-Ca2+ exchange transports and consequently produces Ca2+ overload, which yields cell death. Among the various Ca2+ entry pathways, the Na+-Ca2+ exchanger is known to play one of the major roles during the ischemia/reperfusion of cardioplegia. Consequently, information on the changes in intracellular Ca2+ activities of human cardiac myocytes via the Na+-Ca2+ exchanger is imperative despite previous measurements of Ca2+ current of human single myocytes. In this study, human single myocytes were isolated from the cardiac tissues obtained during open-heart surgery and intracellular Ca2+ activity was measured with cellular imaging techniques employing fluorescent dyes. We report that the Na+-Ca2+ exchanger of adult cardiac myocytes is more susceptible to hypoxic insult than that of young patients.
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Wu CC, Lin LC, Ho YL, Liau CS, Lee YT. Intraventricular isovolumic relaxation flow patterns improve the predicting power of Doppler echocardiography for the left ventricular filling pressure in patients with anterior wall myocardial infarction. Cardiology 2001; 94:200-7. [PMID: 11279327 DOI: 10.1159/000047317] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND AND PURPOSE Previous studies have shown that left ventricular systolic asynchrony affects both the relaxation and filling phases of diastole. The purpose of this study was to delinate how the anterior wall dyssynergy influenced the intraventricular flow redistribution patterns during the isovolumic relaxation (IVR) period, which delineated the changes in diastolic suction performance and, therefore, determined the significant Doppler flow variables for predicting left ventricular filling pressure. METHODS Seventy-three patients with anterior wall myocardial infarction and dyssynergy were enrolled. Those who exhibited the whole IVR intraventricular flow redistributing toward the mitral apparatus, which indicated the reverse physiologic intraventricular pressure gradient in early diastole, were classified as group B, otherwise, as group A. The Doppler echocardiographic variables of mitral inflow were correlated with the left ventricular end-diastolic pressures (LVEDP). RESULTS With lower ejection fraction rate and more apical dyssynergy, the group B patients had much slower mitral flow propagation. For group A patients, the independent determinants for LVEDP were the ratio of mitral flow propagation rate to peak velocity in early diastole, the early mitral flow deceleration time and the IVR time, all occurring in early diastole. In contrast, the only independent determinant for LVEDP in group B patients was the ratio of mitral peak flow velocity in early diastole to that in late diastole. CONCLUSIONS The intraventricular IVR flow patterns could delineate how the left ventricular systolic dyssynergy influenced the diastolic process, and determine which echocardiographic variables were more useful for predicting LVEDP in patients with anterior wall myocardial infarction.
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Lai CL, Chen WJ, Liu YB, Lee YT. Bradycardia and permanent pacing after bilateral thoracoscopic T2-sympathectomy for primary hyperhidrosis. Pacing Clin Electrophysiol 2001; 24:524-5. [PMID: 11341096 DOI: 10.1046/j.1460-9592.2001.00524.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
A 23-year-old woman with craniofacial hyperhidrosis underwent bilateral thoracoscopic T2-sympathectomy. Marked sinus bradycardia with a mean heart rate of 49 beats/min by Holter ECG monitoring occurred after the procedure and persisted for > 2 years. Normal sinus node function was found by an invasive electrophysiological study and unopposed vagotonia after sympathectomy was diagnosed. A permanent pacemaker was implanted. Although reduced heart rate is a common phenomenon after bilateral dorsal sympathectomy, intractable bradycardia with permanent pacing is rare. This patient demonstrates one of the potential cardiac complications of bilateral sympathectomy.
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Chan HL, Wu JC, Chan FK, Choi CL, Ching JY, Lee YT, Leung WK, Lau JY, Chung SC, Sung JJ. Is non-Helicobacter pylori, non-NSAID peptic ulcer a common cause of upper GI bleeding? A prospective study of 977 patients. Gastrointest Endosc 2001; 53:438-42. [PMID: 11275883 DOI: 10.1067/mge.2001.112840] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND Non-Helicobacter pylori, non-NSAID ulcer is relatively common in Western countries. Whether it is a significant problem in the Orient is unclear. The aim of this study was to investigate the incidence of non-H pylori, non-NSAID ulcers presenting with GI bleeding. METHODS A prospective study was done of 1675 consecutive patients presenting with upper GI bleeding over a period of 12 months. Upper endoscopy was performed with biopsy specimens taken from the antrum and body of the stomach for a biopsy urease test (BUT) and histology for detection of H pylori. Exposure to nonsteroidal anti-inflammatory drugs (NSAID) or aspirin within 4 weeks of hospitalization was carefully scrutinized. A 6-week course of treatment with an H2-receptor antagonist was prescribed for patients who did not use an NSAID and had a negative BUT result. Follow-up endoscopy was performed to confirm H pylori status with a BUT and histology. Positive histology at either initial or follow-up endoscopy was used as the standard for diagnosing H pylori infection. RESULTS Among 977 patients who were found to have ulcer bleeding, 434 (44%) had exposure to aspirin or an NSAID. Of the 543 non-NSAID users, 431 (79.4%) had a positive BUT and 112 (20.6%) were BUT negative on initial endoscopy. Eighty-nine of 112 patients who were NSAID negative, BUT negative returned for follow-up endoscopy. Forty-nine of 89 (55.1%) were found to have a positive BUT and positive histology at follow-up endoscopy. Only 40 of 977 (4.1%) patients admitted with ulcer bleeding were confirmed to have non-H pylori, non-NSAID ulcers. CONCLUSIONS Non-H pylori, non-NSAID bleeding ulcer is uncommon. A negative BUT is unreliable for exclusion of H pylori infection during the acute phase of ulcer bleeding.
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Chien KL, Sung FC, Hsu HC, Su TC, Lee YT. Left ventricular mass and correlated atherosclerotic risk factors in young adolescents: report from Chin-Shan community cardiovascular study in Taiwan. Atherosclerosis 2001; 155:431-7. [PMID: 11254914 DOI: 10.1016/s0021-9150(00)00579-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Various subclinical disease indicators can be used as an early stage marker of atherosclerosis. Left ventricular (LV) mass has been related to cardiovascular morbidity and mortality. The distribution of LV mass in Chinese is rarely studied and nothing is known about its relationships with various atherosclerotic risk factors in young teenagers, in particular, aspects of lipid profiles. We performed a community-based survey of 523 males and 555 females, aged 12-15, in Chin-Shan, a suburb area near Taipei, Taiwan. LV mass was calculated from the Penn convention. Normalized LV mass by height with power of 2.7 was defined. LV mass and normalized LV mass were significantly greater in males than in females. There were significant positive correlation coefficients between LV mass and age, blood pressure, body mass index, low density lipoprotein cholesterol (LDL-C), apolipoprotein (Apo) B, fasting insulin levels and significant negative correlation coefficients between LV mass and high density lipoprotein cholesterol (HDL-C) and Apo A1 level in both genders. Multiple linear regression models showed gender and body mass index (BMI) were important factors associated with LV mass or normalized values for adolescents. Age and systolic blood pressure were also significant predictors of LV mass, but not of normalized LV mass values. LV mass values were found to be negatively associated with HDL-C values at marginal statistically significant level. Age and BMI are the most significant factors of echocardiographic LV mass distributions in young adolescent in Taiwan. LV mass may also be associated with atherosclerotic risk factors.
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Chan FK, Chung SC, Suen BY, Lee YT, Leung WK, Leung VK, Wu JC, Lau JY, Hui Y, Lai MS, Chan HL, Sung JJ. Preventing recurrent upper gastrointestinal bleeding in patients with Helicobacter pylori infection who are taking low-dose aspirin or naproxen. N Engl J Med 2001; 344:967-73. [PMID: 11274623 DOI: 10.1056/nejm200103293441304] [Citation(s) in RCA: 480] [Impact Index Per Article: 20.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
BACKGROUND Many patients who have had upper gastrointestinal bleeding continue to take low-dose aspirin for cardiovascular prophylaxis or other non-steroidal antiinflammatory drugs (NSAIDs) for musculoskeletal pain. It is uncertain whether infection with Helicobacter pylori is a risk factor for bleeding in such patients. METHODS We studied patients with a history of upper gastrointestinal bleeding who were infected with H. pylori and who were taking low-dose aspirin or other NSAIDs. We evaluated whether eradication of the infection or omeprazole treatment was more effective in preventing recurrent bleeding. We recruited patients who presented with upper gastrointestinal bleeding that was confirmed by endoscopy. Their ulcers were healed by daily treatment with 20 mg of omeprazole for eight weeks or longer. Then, those who had been taking aspirin were given 80 mg of aspirin daily, and those who had been taking other NSAIDs were given 500 mg of naproxen twice daily for six months. The patients in each group were then randomly assigned separately to receive 20 mg of omeprazole daily for six months or one week of eradication therapy, consisting of 120 mg of bismuth subcitrate, 500 mg of tetracycline, and 400 mg of metronidazole, all given four times daily, followed by placebo for six months. RESULTS We enrolled 400 patients (250 of whom were taking aspirin and 150 of whom were taking other NSAIDs). Among those taking aspirin, the probability of recurrent bleeding during the six-month period was 1.9 percent for patients who received eradication therapy and 0.9 percent for patients who received omeprazole (absolute difference, 1.0 percent; 95 percent confidence interval for the difference, -1.9 to 3.9 percent). Among users of other NSAIDs, the probability of recurrent bleeding was 18.8 percent for patients receiving eradication therapy and 4.4 percent for those treated with omeprazole (absolute difference, 14.4 percent; 95 percent confidence interval for the difference, 4.4 to 24.4 percent; P=0.005). CONCLUSIONS Among patients with H. pylori infection and a history of upper gastrointestinal bleeding who are taking low-dose aspirin, the eradication of H. pylori is equivalent to treatment with omeprazole in preventing recurrent bleeding. Omeprazole is superior to the eradication of H. pylori in preventing recurrent bleeding in patients who are taking other NSAIDs.
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Chang BC, Lim CY, Park PW, Park KY, Lee YT, Kim YJ. Volume reduction surgery for end-stage heart failure: experience in Korea. J Card Surg 2001; 16:159-64. [PMID: 11766835 DOI: 10.1111/j.1540-8191.2001.tb00502.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Partial left ventriculectomy (PLV) is regarded as one of the alternatives to heart transplantation for idiopathic dilated cardiomyopathy (d-CMP). Between June 1996 and March 2000, 20 patients underwent left ventricular volume reduction surgery at five major cardiac centers in Korea. PLV was performed in 16 patients with d-CMP and in 1 patient with ischemic CMP. The modified Dor procedure was performed in three patients; two patients with d-CMP and one patient with ischemic CMP. Median age was 35 years (range 3-64 years). There were 13 male and 7 female patients; there were 4 patients in Class III and 16 patients in Class IV. Among the 16 patients in Class IV, 5 patients were inotropic dependent, 2 patients were resuscitated from cardiac arrest or shock in hospital, and 1 patient was treated with intra-aortic balloon pumping. Operative technique for PLV was the same as described by Batista and colleagues. For the modified Dor procedures, the apical left ventricle was opened and a circumferential pursestring suture was placed at the base of both papillary muscles to reduce the diameter of the left ventricle concomitant with mitral annuloplasty. Mitral valve repair was performed in 15 patients and mitral valve replacement was performed in 1 patient. Moderate-to-severe tricuspid regurgitation was noted in 12 patients (with tricuspid annuloplasty in 11 of these patients and replacement in 1 patient). Postoperatively, there were seven operative deaths after PLV and one death after the modified Dor procedure. Cause of death after PLV was right heart failure in four of the seven cases, sepsis in one case, and ventricular tachyarrhythmia in the remaining two cases. After the modified Dor procedure, there was one operative death with left ventricular failure. Postoperatively, mean ventricular end-diastolic dimension markedly decreased from 75.3 mm to 50.9 mm. However, this dimension had increased slightly to 58.2 mm, an average observed 22 months later. Mean left ventricular ejection fraction (LVEF) improved significantly from 20.6% to 33.5% (p < 0.0001), but decreased to 28.5% on average 22 months later (p = 0.058). Eleven patients were discharged from the hospital and followed-up for a mean of 20.2 months (range 1-41 months). During the early postoperative period, most were in good condition. However, heart failure progressed with mitral regurgitation in four patients, two of whom underwent heart transplantation. In conclusion, PLV for d-CMP seems to be an effective alternative surgical procedure to heart transplantation in Korea. The modified Dor procedure may be another alternative to transplantation for left ventricular volume reduction. However, in patients showing progression of heart failure, early intervention with ventricular assist or heart transplantation will be necessary. Also, further studies will be necessary for selection criteria and for prevention of ventricular tachyarrhythmia.
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