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T S Hsu

Publications and source records attributed to T S Hsu.

At least 19 recordsLinked to original sources
PubMed2005

Exercise-induced myocardial ischaemia complicated by paroxysmal complete atrioventricular block.

This study describes a case of exercise-induced myocardial ischaemia accompanied by complete atrioventricular block (CAVB). A 59-year-old man with major depression, treated with regular imipramine and lithium for 20 years, experienced syncope episodes during exercise. Exercise, testing initially, identified ST depression in the inferior leads, and later found CAVB resulting in syncope and seizure. The patient recovered completely after resuscitation. Myocardial ischaemic markers were negative, but 35% stenosis was detected in the distal left main coronary artery by angiography. The combined use of verapamil, nitrate and aspirin was treated as the possible coronary spasm. Repeat treadmill caused negative ischaemic study or exercise-induced arrhythmia, 7 days later. The pathophysiology of the very rare exercise-induced paroxysmal CAVB has been reviewed.

Antidepressive Agents↗
PubMed2001

Importance of hyperhomocysteinemia as a risk factor for venous thromboembolism in a Taiwanese population. A case-control study.

OBJECTIVE: To determine the current status of hyperhomocysteinemia, which is a known risk for venous thrombosis (DVT), in Taiwan. SUBJECTS: 101 unselected patients with a minimum of one episode of deep leg DVT, either initial inpatients or current compliant outpatients in a teaching hospital. METHODS: Various thrombophilic risks, gene polymorphism and clinical predisposition were evaluated. RESULTS AND CONCLUSIONS: Patients presented higher fast total plasma homocysteine (hcy) levels than age- and sex-matched controls did (14.1 vs. 9.94 microM). Based on the 95th percentile of control values, hyperhomocysteinemia had a four- to nine-fold risk for DVT, irrespective of clinical predisposition, as well as other thrombophilic risks surveyed. Polymorphism of a metabolizing enzyme, methylenetetrahydrofolate reductase (MTHFR), was not associated with DVT, although homozygous thermolabile mutation tended to have higher plasma hcy levels. Factor V Leiden was absent in analysis of 80 patients. In complete evaluation (hcy, antithrombin (AT), protein S (PS), protein C (PC), lupus anticoagulant (LA), anticardiolipin antibody) of a subset of 83 patients hyperhomocysteinemia was the most prevalent risk (33.7%), with PC or PS deficiencies following (22.9%). Thus, hyperhomocysteinemia is a prominent risk for DVT in Taiwan.

Adult↗
PubMed2001

Beard dermatitis due to para-phenylenediamine use in Arabic men.

The most common active ingredient in hair coloring is para-phenylenediamine (PPDA), which can produce contact dermatitis, particularly in persons who dye their scalp hair and in hairdressers. We have identified another group of patients also at risk, namely men from Arab countries, who commonly grow beards and dye them. We searched the computerized patient database at the Mayo Clinic for patients with beard dermatitis associated with dye use. Eight Arabic men presented to the Mayo Clinic between 1994 and 1999 with beard dermatitis and a positive patch test to PPDA. The lesions were described as pruritic, erythematous, papular eruptions that developed in the jaw area after each application of beard dye. The symptoms subsided after the patients discontinued use of the PPDA-containing dye and received treatment with topical corticosteroids. Allergic contact dermatitis in the beard area due to PPDA occurs in Arabic men as a result of their propensity to dye their beards.

Arabs↗
PubMed2001

Chemical denaturation and elevated folding temperatures are required for wild-type activity and stability of recombinant Methanococcus jannaschii 20S proteasome.

The 20S proteasome from the extreme thermophile Methanococcus jannaschii (Mj) was purified and sequenced to facilitate production of the recombinant proteasome in E. coli. The recombinant proteasome remained in solution at a purity level of 80-85% (according to SDS PAGE) following incubation of cell lysates at 70 degrees C. Temperature-activity profiles indicated that the temperature optima of the wild-type and recombinant enzymes differed substantially, with optimal activities occurring at 119 degrees C and 95 degrees C, respectively. To ameliorate this discrepancy, two recombinant enzyme preparations were produced, each of which included denaturation of the proteasome by 4 M urea followed by high-temperature (85 degrees C) dialysis. The wild-type temperature optimum was restored, but only if proteasome subunits were denatured and refolded prior to assembly (a preparation designated as alpha & beta). In contrast, when proteasome assembly preceded denaturation (designated alpha + beta) the optimum temperature was raised to a lesser degree. Moreover, the alpha & beta and alpha + beta preparations had apparent thermal half-lives at 114 degrees C of 54.2 and 26.2 min, respectively, and the thermostability of the less stable enzyme was more sensitive to a reduction in pH. Attainment of wild-type activity and stability thus required the proper folding of both the alpha- and beta-subunits prior to proteasome assembly. Consistent with this behavior, dual-scanning calorimetry (DSC) measurements revealed differences in the reassembly efficiency of the two proteasome preparations. The ability to produce structural conformers with dramatically different thermal optima and thermostabilities may facilitate the determination of molecular forces and structural motifs responsible for enzyme thermostablity and high-temperature activity.

Calorimetry, Differential Scanning↗
PubMed2001

The C677T mutation of the methylenetetrahydrofolate reductase gene is not associated with the risk of coronary artery disease or venous thrombosis among Chinese in Taiwan.

OBJECTIVES: We sought to investigate the association between the methylenetetrahydrofolate reductase (MTHFR) gene C677T mutation and the risk of coronary artery disease (CAD), myocardial infarction (MI) and venous thrombosis (VT) in a Chinese population in Taiwan. METHODS: The subjects included 218 CAD patients, 107 VT patients, and their age- and sex-matched controls. DNA was extracted from the blood and genotypes were determined by polymerase chain reaction, restriction mapping with HinfI and gel electrophoresis. RESULTS: The distribution of MTHFR genotypes was similar in the CAD cases and controls; the genotype TT was present in 6.0% of CAD patients, as compared to 6.9% of CAD control subjects (p = 0.165; odds ratio = 0. 86; 95% confidence interval = 0.40-1.85). The frequency of the T allele was also similar in CAD cases and controls (25.5% vs. 24.8%; p = 0.788). There was no significant association between TT homozygosity and the risk of MI. The genotype distributions and the frequency of the T allele were also similar in VT cases and controls. CONCLUSIONS: Our data suggest that there is no association between the C677T mutation of the human MTHFR gene and the risk of CAD or VT among Chinese in Taiwan.

Alleles↗
PubMed1999

Characterization of atrioventricular nodal reentry with continuous atrioventricular node conduction curve by double atrial extrastimulation.

BACKGROUND: Characterization of typical atrioventricular nodal reentrant tachycardia (AVNRT) with continuous AVN conduction (A1A2/A2H2) curves by double atrial extrastimulation (A1A2A3) has never been systematically studied. METHODS AND RESULTS: This study was composed of 33 patients with typical AVNRT and continuous AVN conduction curves (group 1) and 103 patients with AVNRT and discontinuous AVN conduction curves (group 2). Using A1A2A3 with predefined fast pathway-conducted A2, we examined the effects of slow pathway ablation on the A2A3/A3H3 curves in both groups. In group 1, anterograde AVN effective refractory period (272+/-33 versus 277+/-47 ms, P>0.05) and AVN Wenckebach block cycle length (320+/-45 versus 343+/-59 ms, P>0.05) remained unchanged after ablation. A2H2max was shorter in group 1 than group 2 (237+/-89 versus 395+/-72 ms, P<0.05) at baseline. It shortened in group 2 (395+/-72 versus 221+/-78 ms, P<0.001) but remained unchanged in group 1 (237+/-89 versus 214+/-59 ms, P>0.05) after ablation. A1A2A3 could further disclose discontinuous A2A3/A3H3 curves in 29 patients of group 1. A3H3max shortened in both groups (375+/-81 versus 238+/-82 ms, P<0.001, and 419+/-104 versus 220+/-78 ms, P<0.001, respectively) in a similar fashion. Successful ablation resulted in loss of the left portion of the A2A3/A3H3 curves in the 4 patients of group 1 with continuous A2A3/A3H3 curves. CONCLUSIONS: Use of A1A2A3 could expose discontinuous A2A3/A3H3 curves in most patients with continuous A1A2/A2H2 curves. Significant shortening of A3H3max after ablation may be indicative of successful elimination of AVNRT.

Catheter Ablation↗
PubMed1999

Critical appraisal of exercise variables: a treadmill study.

BACKGROUND: New criteria for diagnosing ischemic response to treadmill exercise testing (TET) have continuously been proposed. Simultaneous comparison of test performances according to these criteria is likely contributory to interpreting TET and needs to be updated time after time. This study was conducted to accomplish this end. METHODS: A comparison of test performances of various TET variables for a cohort of 107 clinical normals and 139 angiographic patients with normal resting electrocardiograms was performed. Angiographic references included enumeration of diseased coronary vessels, Gensini's and Duke's coronary scores, left ventricular wall motion score and ejection fraction at rest. RESULTS: The ST-segment-related variables (depression, integral, and heart-rate-adjusted slope or index) outdid non-ST-segment variables (changes in R amplitude, the Athens QRS score, peak exercise blood pressure increment and recovery pressure ratios; most P < 0.05) in diagnosing coronary artery disease. Among them the heart-rate-adjusted ST-segment depression performed still better. This trend was not evident in identifying left main and three-vessel disease. However, correlation to the coronary scores favored the ST-segment-related criteria (r = 0.18-0.39, P < 0.05 to P < 0.001 versus r = 0.05-0.23, NS to P < 0.01) for evaluating severity of coronary artery disease. CONCLUSIONS: For patients with normal resting electrocardiograms, the adjustment of ST-segment depression for heart rate is valuable for evaluating coronary artery disease.

Cardiac Catheterization↗
PubMed1999

Superior vena cava syndrome as a complication of transvenous permanent pacemaker implantation.

Venous thrombosis induced by a transvenous permanent pacemaker is a common complication. However, superior vena cava (SVC) syndrome caused by pacemaker leads is only occasionally seen and its prevalence has been estimated to be less than 1 in 1000 pacemaker patients. Herein, we report a Taiwanese patient of high grade AV block, who presented with SVC syndrome 2 years after transvenous permanent pacemaker implantation. This case features fibrotic stenosis of the junction of right brachiocephalic trunk and SVC, and an extensive thrombus formation resulting in complete obliteration of the left brachiocephalic vein. The collateral circulation was so delicate that he still could lead a rather normal life, even if anticoagulant therapy proved to be ineffective from an angiographic point of view.

Female↗
PubMed1998

Gender differences in baseline variables, therapies and outcomes in Chinese patients with acute myocardial infarction.

We prospectively studied the gender differences of baseline variables, therapies, and outcomes among a cohort of 369 Chinese patients with acute myocardial infarction from 1990 to 1995. There were 277 male and 92 female patients. The male gender had a younger mean (+/-SD) age (61.5+/-10.7 vs. 67.1+/-11.7 years, P<0.0001). Hypercholesterolemia (201.2+/-44.2 vs. 187.5+/-43.7 mg/dl, P=0.0111) and obesity (25.0 vs. 15.9%, P=0.0494) were more prominent in the female. Smoking was more prevalent in the male (78.3 vs. 18.5%, P<0.0001). The male group also had more frequent use of thrombolytic agents (19.1 vs. 9.8%, P=0.0377), beta-blockers (61.7 vs. 47.8%, P=0.0191) and heparin (25.3 vs. 12.0%, P=0.0075); but less use of angiotensin-converting enzyme inhibitors (6.9 vs. 15.2%, P=0.0149). The condition on admission was worse in the female group (Killip classification (1.5+/-0.9 vs. 1.9+/-1.0, P=0.0022), myocardial failure (8.7 vs. 2.9%, P=0.0178) and cardiomegaly (65.2 vs. 53.1%, P=0.0419). During a follow-up duration of 26.4+/-24.1 and 22.9+/-23.9 months respectively, the mortality rate was lower in the male (19.5 vs. 30.4%, P=0.0288). However after adjustment for the effect of age, the differences in Killip classification, myocardial failure, cardiomegaly and mortality became insignificant.

Aged↗
PubMed1998

Unusual coronary artery ectasia and stenosis in a patient with systemic lupus erythematosus and acute myocardial infarction.

Acute myocardial infarction is an important and sometimes fatal complication of systemic lupus erythematosus (SLE). We describe a case of acute myocardial infarction in a 23-year-old woman with SLE. Angiography revealed coronary ectasia in the left main and proximal circumflex coronary arteries, as well as a stenotic lesion in the left anterior descending artery. The possible pathophysiology is discussed.

Adult↗
PubMed1997

Angiotensinogen and angiotensin-I converting enzyme gene polymorphisms and the risk of coronary artery disease in Chinese.

The homozygous deletion allele (DD) of the angiotensin-I converting enzyme (ACE) gene and the T235 homozygote of the angiotensinogen (AGT) gene have been reported to be correlated with an increased prevalence of coronary artery disease (CAD) and myocardial infarction (MI). The importance of the DD genotype and T235 homozygote as genetic risk factors for CAD in Chinese remains uncertain. This study included 426 patients who underwent coronary angiography and 180 healthy subjects without clinical evidence of CAD. Coronary angiography identified 268 patients with CAD (CAD group) and 158 patients without CAD. The healthy subjects and patients without angiographic evidence of CAD constituted the control group. Three polymorphisms were studied: an insertion/deletion (I/D) polymorphism of the ACE gene and the T174 M and M235T polymorphisms of the AGT gene. No association was found between any of the three studied polymorphisms and the risk of CAD or MI in Chinese using univariate or multivariate analysis. In multivariate analysis, the relative risks were 1.20 (95% confidence interval = 0.91-1.61, P = 0.20) for the DD genotype, 1.05 (95% CI = 0.82-1.35, P = 0.69) for the T174 homozygote, and 1.19 (95% CI = 0.91-1.55, P = 0.20) for the T235 homozygote. Similarly, no significant difference was found in the frequencies of the DD genotype and the T174 and T235 homozygotes between the control group, the CAD group, the non-MI group, and the MI group when analyzed according to sex, age, or degree of risk. Our data suggest that neither the DD genotype of the ACE I/D polymorphism nor the T174 and T235 homozygotes of the AGT gene confer significant risk for CAD or MI in Chinese.

Angiotensinogen↗
PubMed1997

Interaction between obesity and genetic polymorphisms in the apolipoprotein CIII gene and lipoprotein lipase gene on the risk of hypertriglyceridemia in Chinese.

To understand the effects of the interaction between genetic polymorphisms and obesity on the risk of hypertriglyceridemia (HTG), two polymorphisms, an SstI polymorphism on the apolipoprotein CIII gene and a HindIII polymorphism on the lipoprotein lipase gene, were analyzed in 339 Chinese subjects with (82 cases in the HTG group) or without HTG (257 cases in the control group). Our data revealed that the frequencies of obesity, the SstI minor allele (S2), and the HindIII major allele (H+) in the HTG group were significantly higher than in the control group. Subgroup analysis revealed that the association between these two polymorphisms and HTG occurred predominantly in nonobese subjects and in subjects with the less hypertriglyceridemic genotype of another polymorphism. Multivariate logistic regression analysis showed that all three risk factors (obesity, S2-containing chromosome, and H+ homozygosity) were associated with HTG, and an interaction was found between obesity and H+ homozygosity for the occurrence of HTG. The risk of HTG increased significantly with combinations of risk factors. Subjects can be divided into low or high risk groups for HTG using such combinations. These results provide evidence of interaction between obesity and the HindIII polymorphism of the lipoprotein lipase gene on the risk of HTG.

Alleles↗
PubMed1996

The G1691A mutation of the coagulation factor V gene (factor V Leiden) is rare in Chinese: an analysis of 618 individuals.

To understand the allele frequency of the G1691A mutation of the coagulation factor V gene (factor V Leiden) in Chinese, 618 Chinese individuals, including 54 cases with venous thrombosis, were analyzed. Only one case in the control group was heterozygous for the 1691G allele and the 1691A allele. Our data suggest that the factor V Leiden is rare in Chinese.

Alleles↗
PubMed1996

Defecation induced deep venous thrombosis. A case report.

While the risk of deep venous thrombosis (DVT) during prolonged fights is well recognized, we present the case of a 54-year-old male who suffered a deep venous thrombosis following defecation. Defecation, through a combination of the Valsalva maneuver and squatting, led to a DVT due to venous stasis, most marked in the left leg. Color-duplex scanning not only proved a convenient diagnostic tool but also allowed for monitoring and documentation of popliteal and saphenous vein recanalization. Being non-invasive and complication-free, color-duplex scanning should be considered for any patient in whom DVT is a possibility.

Angiography↗
PubMed1996

Deep venous thrombosis in Taiwan.

We retrospectively reviewed all patients with a final diagnosis of deep venous thrombosis (DVT) treated at Linkou Chang Gung Memorial Hospital between 1989 and 1995. There were a total of 245 patients with a mean age of 58 years (males 56 and females 59), ranging from 11 to 89 years. The ratio of left to right leg involvement was 2.4 to 1 (166 to 71), however, the right leg was more likely to lead to an acute pulmonary embolism, with a ratio of 3.0 to 1 (9/ 71 to 7/166 patients). Among these patients, 16.3% (40) had cancer. The most frequently involved system was the GI system (16). Adenocarcinoma proved the most common type of malignancy 62.5% (25/40). From this analysis, we found the left leg had a higher likelihood of thrombosis but a DVT of the right leg was more frequently associated with an acute pulmonary embolism. As with previous reports there was a strong relationship between cancer and DVT and the development of a deep venous thrombosis requiring a search for an underlying malignancy in those patients with an unexplained DVT.

Acute Disease↗
PubMed1996

Extensive bullae formation in acute iliofemoral venous thrombosis.

A 58-year-old man presented with an acutely painful swollen left leg which was cyanotic and crowded with cutaneous bullae. After confirmation with color duplex ultrasound, intravenous streptokinase therapy was commenced with a bolus of 250,000 i.u. followed by maintenance infusion of 100,000 i.u. hourly for 72 hours. Treatment was changed to heparin for 14 days and then oral warfarin for another 6 months. Effacement of bullae accompanied subsidence of swelling of the leg. This case highlights the potential contribution of fluid retention in acute deep venous thrombosis to extensive bullae formation. This has not been previously reported in the literature.

Acute Disease↗
PubMed1994

Comparisons between female and male patients with mitral stenosis.

OBJECTIVE: To compare Doppler, echocardiographic, and clinical variables in female and male patients with mitral stenosis. DESIGN: Observational study in consecutive patients with mitral stenosis of cross sectional and Doppler echocardiographic and clinical variables and a retrospective search for a history of systemic embolism. SETTING: A medical centre with 3000 beds, serving both urban and rural populations. PATIENTS: 500 consecutive patients with an echocardiographic mitral valve area of 2 cm2 or less. 331 (66.2%) were female and 169 (33.8%) male (mean (SD) ages of 49 (13) and 48 (14) respectively). MAIN OUTCOME MEASURES: Mitral valve areas by echocardiographic planimetry and Doppler pressure half-time method, peak early diastolic mitral velocity and pressure gradient, echocardiographic score of mitral valve, left atrial end systolic diameter, frequency of left atrial thrombus and smoky echoes as well as various valve lesions detected with Doppler and echocardiography, cardiac rhythm, symptomatic functional class of heart failure, and history of systemic embolism. RESULTS: The prevalence of significant tricuspid (22% v 9%, P < 0.001) and pulmonary regurgitation (5% v 1%, P = 0.018) was higher in the female patients than in the male patients. Female patients also had a higher peak regurgitant velocity (3.2 (0.7) v 2.9 (0.7) m/s, P = 0.007) and pressure gradient (41 (21) v 36 (19) mm Hg, P = 0.010) across the tricuspid valve. However, the male patients had a higher echocardiographic score (9.7 (2.4) v 7.0 (2.3), P < 0.001) and a smaller Doppler-derived mitral valve area (0.9 (0.4) v 1.0 (0.4) cm2, P = 0.027). There were no differences between the female and the male patients in mitral valve area measured by planimetry, peak early diastolic mitral velocity and pressure gradient, and left atrial end systolic diameter or in the prevalence of atrial fibrillation, left atrial thrombus, left atrial smoky echoes, significant aortic stenosis, aortic regurgitation, or heart failure of New York Heart Association class III or IV. CONCLUSIONS: Female patients not only had a higher prevalence of mitral stenosis but also had a higher prevalence of associated tricuspid and pulmonary regurgitation along with a higher velocity and gradient of tricuspid regurgitation. The echocardiographic score was higher in male patients, however. These findings suggest that the pathophysiology of mitral stenosis is different in the two sexes and that gender should be taken into account when therapeutic strategies are formulated.

Echocardiography↗