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991.

Aims

To investigate the relationship of type 2 diabetes duration and myocardial blood flow (MBF) assessed by myocardial CT perfusion.

Materials and methods

We prospectively included 140 patients with type 2 diabetes who underwent dynamic myocardial CT perfusion exam. MBF of the remote myocardium was calculated using the deconvolution technique and the Voronoi method. The relationships of MBF and diabetic duration, diabetic complications, conventional risk factors, coronary calcium, and coronary stenosis were assessed by logistic regression analysis.

Results

A weak but significantly negative relationship was present between diabetes duration and MBF (R2?=?0.05, p?<?0.01). The average MBF of patients with a duration of >8?years was 13% lower than that of the remaining patients (1.11?±?0.35 vs 1.28?±?0.27?ml?min?1?g?1, p?<?0.01). Duration of one year was associated with a 6% increased risk for low MBF (<1.18?ml?min?1?g?1) (odds ratio 1.06, 95% confidence interval 1.01–1.12, p?<?0.05). Calcium score was also a significant factor for low MBF (odds ratio 1.08 (per 100 Agatston units), 95% confidence interval 1.01–1.17, p?<?0.05).

Conclusion

Longer diabetes duration is associated with lower MBF independent of conventional cardiac risk factors or the presence of coronary stenosis.  相似文献   
992.

Background

Visceral adiposity indicators and the product of triglyceride and fasting plasma glucose (TyG) index-related parameters are effective surrogate markers for insulin resistance (IR) and are predictors of metabolic syndrome and diabetes mellitus. However, their genetic determinants have not been previously reported. Pleiotropic associations of LIPC variants have been observed in lipid profiles and atherosclerotic cardiovascular diseases. We aimed to investigate LIPC polymorphisms as the genetic determinants of adiposity status, visceral adiposity indicators and TyG index-related parameters.

Methods

A total of 592 participants from Taiwan were genotyped for three LIPC single nucleotide polymorphisms (SNPs).

Results

The LIPC SNPs rs2043085 and rs1532085 were significantly associated with body mass index (BMI), waist circumference (WC), lipid accumulation product, visceral adiposity index, and TyG index-related parameters [including the TyG index, TyG with adiposity status (TyG-BMI), and TyG-WC index], whereas the rs1800588 SNP was only significantly associated with the TyG index. The associations became nonsignificant after further adjustment for serum TG levels. No significant association was observed between any the studied LIPC SNPs and IR status.

Conclusion

Our data revealed a pleiotropic association between the LIPC variants and visceral adiposity indicators and TyG index-related parameters, which are mediated by serum TG levels.
  相似文献   
993.
In this article we have reviewed the mechanisms of atrial fibrillation (AF) with special emphasis on the thoracic veins. Based on a number of features, the thoracic veins are highly arrhythmogenic. The pulmonary vein (PV)-left atrial (LA) junction has discontinuous myocardial fibers separated by fibrotic tissues. The PV muscle sleeve is highly anisotropic. The vein of Marshall (VOM) in humans has multiple small muscle bundles separated by fibrosis and fat. Insulated muscle fibers can promote reentrant excitation, automaticity, and triggered activity. The PV muscle sleeves contain periodic acid-Schiff (PAS)-positive large pale cells that are morphologically reminiscent of Purkinje cells. These special cells could be the sources of focal discharge. Antiarrhythmic drugs have significant effects on PV muscle sleeves both at baseline and during AF. Both class I and III drugs have effects on wavefront traveling from PV to LA and from LA to PV. Separating the thoracic veins and the LA with ablation techniques also prevents PV-LA interaction. By reducing PV-LA interaction, pharmacological therapy and PV isolation reduce the activation rate in PV, intracellular calcium accumulation, and triggered activity. Therefore, thoracic vein isolation is an important technique in AF control. We conclude that thoracic veins are important in the generation and maintenance of AF.  相似文献   
994.
Primary appendiceal cancer is a rare neoplasm. We analyzed the clinicopathologic characteristics and clinical outcomes of patients with primary appendiceal cancer treated at Buddhist Tzu Chi General Hospital in Eastern Taiwan. We reviewed the medical records of patients who had appendectomy at our hospital over a 10-year period and studied those who had histologically proven malignant appendiceal neoplasms. We treated eight such patients: seven males and one female. Their median age was 66 years (range, 59-78 years). There were three mucinous adenocarcinomas, two colonic type adenocarcinomas, and three adenocarcinoids. No patient was diagnosed correctly before surgery, and five (62.5%) had a preoperative diagnosis of acute appendicitis. Operative procedures included right hemicolectomy or partial colectomy in four, debulking and right hemicolectomy in three, and appendectomy only in one. With a mean follow-up of 64 months (range, 3-132), patients with adenocarcinoid lesions had better prognosis than those with adenocarcinomas. The important prognostic factors of primary appendiceal cancer included histologic subtypes and the extent of dissemination. In our series, palliative resection for disseminated lesions with or without additional chemotherapy resulted in long-term survival.  相似文献   
995.
Diphyllobothriasis latum is an intestinal parasitosis caused by the ingestion of mostly raw fresh-water fish containing plerocercoids of Diphyllobothrium latum. We report an 8-year-old boy who came to our hospital with the complaint of a tapeworm hanging from the anus after defecation. The other symptom was mild abdominal cramping for a period of 1 year. The laboratory examination did not reveal anemia or vitamin B12 deficiency. Examination of gravid proglottids with rosette-like central uterus and typically operculated eggs of D. latum confirmed the diagnosis. The morphologic characters of proglottids and eggs size are compatible with D. latum. The patient had a history of eating uncooked fish for 1 year. Salmonids may be the infection source. He was treated with two doses of praziquantel and passed about 183 cm in length of all proglottids. There is a high prevalence of diphyllobothriasis latum in the northern temperate areas, but it is very rare in children. This patient is the first child case reported in Taiwan.  相似文献   
996.
OBJECTIVE: To submit serum levels of matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) to statistical analyses to test their exact degrees of clinical usefulness as biomarkers for detecting high disease activity in ankylosing spondylitis (AS), comparing them with erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP). METHODS: Serum levels of MMP-1, -3, -9 and TIMP-1 and -2 were measured in 42 AS patients and 20 healthy controls. The Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) provided the gold standard for measuring disease activity. Patients with BASDAI > or =4 were regarded as having high disease activity. The results were compared with results for a separate cohort of 41 AS patients. RESULTS: Only MMP-3 levels were significantly higher in AS patients than in healthy controls (P<0.001). Within AS patients, MMP-3 levels were also higher in patients with high disease activity compared with those with low disease activity, and correlated significantly with BASDAI (r = 0.366, P = 0.017) and functional indices (r = 0.344, P = 0.026). The correlation with BASDAI was stable in a 1-yr follow-up (r = 0.464, P = 0.095) and reproducible with two different enzyme-linked immunosorbent assays. For detecting high disease activity, the sensitivity and specificity of MMP-3 level was 69.2 and 68.8% respectively. Most importantly, using receiver operating characteristic plots to analyse the two cohorts, MMP-3 was more accurate than ESR and CRP in detecting AS patients with high disease activity (P = 0.01 and P = 0.009, respectively). CONCLUSION: Using several analytical approaches that have never been reported previously, we showed that MMP-3 is a more useful biomarker than ESR and CRP to detect high disease activity in AS.  相似文献   
997.
AIM: To assess the incidence of and risk factors for gallstone disease (GSD) among type 2 diabetics in Kinmen, Taiwan. METHODS: A screening program for GSD was performed by two specialists who employed real-time abdominal ultrasound to examine the abdominal region after patients had fasted for at least eight hours. Screening, which was conducted in 2001, involved 848 patients diagnosed with type 2 diabetes. After exclusion of 63 subjects with prevalent GSD, 377 participants without GSD were invited in 2002 for a second round of screening. A total of 281 (74.5%) subjects were re-examined. RESULTS: Among the 281 type 2 diabetics who had no GSD at the first screening, 10 had developed GSD by 2002. The incidence was 3.56% per year (95%CI: 1.78% per year-6.24% per year). Using a Cox regression model, age (RR = 1.07, 95% CI: 1.00-1.14), waist circumference (RR = 1.12, 95% CI: 1.01-1.29), and ALT (RR = 1.13, 95%CI: 1.01-1.26) appeared to be significantly correlated with development of GSD. CONCLUSION: Older age is a known risk factor for the development of GSD. Our study shows that greater waist circumference and elevated ALT levels are also associated with the development of GSD among type 2 diabetics in Kinmen.  相似文献   
998.
OBJECTIVES: This hospital-based study was conducted to determine the survival rates of patients after coronary artery bypass grafting (CABG) surgery and the associated prognostic factors related to all-cause mortality during a 7-year follow-up in Taiwan. METHODS AND RESULTS: Between January 1997 and December 2003, the medical records of 1877 patients who underwent primary, isolated CABG surgery were studied. The Kaplan-Meier method was used to estimate survival. Multiple Cox regression was used to investigate the independence of prognostic factors associated with all-cause mortality. Of the 1877 patients who underwent CABG surgery, 192 expired during the 7-year study period.The overall patient survival rate was 85.96% (95% CI: 83.74-88.16). Using multiple Cox regression analysis, in addition to female gender, older age at surgery, pulmonary oedema, longer ischaemic time, longer cardiopulmonary bypass time, and poorer postoperative left ventricular ejection fraction were significant factors associated with all-cause mortality for both men and women. Associated prognostic factors varied by gender. For men, smoking (RR = 2.82, 95% CI: 1.06-4.16), respiratory failure (RR = 6.88, 95% CI: 3.29-14.40) and cardiogenic shock (RR = 4.04, 95% CI: 2.13-7.67) were significantly related to all-cause mortality, but not for women. Sepsis (RR = 8.97,95% CI: 1.19-19.81) and ICU stay (RR = 1.03,95% CI: 1.01-1.05) were significantly related to all-cause mortality among female patients only. CONCLUSIONS: Several gender-related differences were noted pertaining to all-cause mortality and the relationships between smoking, sepsis, respiratory failure, cardiogenic shock, and ICU stay.  相似文献   
999.
Scarring and collagen deposition in the valves and destruction of myocytes may result from the combined effects of a smoldering rheumatic process and a constant trauma to the mitral valve or aortic valve by the turbulent flow in rheumatic heart disease (RHD). It has been suggested that angiotensin I-converting enzyme (ACE) may be responsible for the increased valvular fibrosis and calcification in the pathogenesis of RHD. However, the role of ACE genetic variant in RHD has not been studied among the Chinese population in Taiwan. Hence, a case-controlled study was carried out to investigate the possible relationship between the ACE gene insertion/deletion (I/D) and G2350A polymorphisms and RHD. A group of 115 patients with RHD documented by echocardiography and 100 age- and sex-matched normal control subjects were studied. ACE gene I/D and G2350A polymorphisms were identified by polymerase chain reaction-based restriction analysis. There was a significant difference in the distribution of ACE I/D genotypes (P = 0.02) and allelic frequencies (P = 0.04) between RHD cases and normal controls. An odds ratio for the risk of RHD associated with the ACE I/D II genotype was 2.12 (95% CI, 1.21-3.71). An odds ratio for the risk of RHD associated with the ACE I allele was 1.50 (95% CI, 1.02-2.21). The ACE G2350A polymorphism showed no association with RHD (P = 0.90). Further categorization of RHD patients into mitral valve disease and combined valve disease subgroups revealed no statistical difference in these gene polymorphisms when compared between the two subgroups. This study shows that patients with RHD have a higher frequency of ACE II genotype and I allele, which supports a role for ACE I/D gene polymorphisms in determining the risk of RHD in Taiwan Chinese.  相似文献   
1000.
OBJECTIVE: Coronary artery plaque rupture is a sudden, unpredictable event leading to acute coronary syndrome. Thus far, there is no clinical characteristic to distinguish the patients at risk for acute myocardial infarction from those with more stable coronary artery disease. The purpose of this study was to identify clinical predictors of first ST-segment elevation myocardial infarction (STEMI). METHODS: We retrospectively compared 116 consecutive patients presenting with their first STEMI for primary angioplasty and 216 ambulatory patients with stable angina requiring their first coronary intervention. RESULTS: Patients with STEMI were younger, more likely to be smokers, but less likely to have hypertension or hypercholesterolemia. Diabetes was present equally between the two groups. Cardioprotective medication usage, such as aspirin and statin, was much lower among patients presenting with their first STEMI. CONCLUSIONS: Thus, patients with STEMI presumably from plaque rupture have fewer traditional risk factors compared with patients with stable angina. Identifying these vulnerable patients at risk for plaque rupture may enable early institution of cardioprotective pharmacotherapy to prevent their first acute coronary syndrome occurrence.  相似文献   
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