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51.
We aimed to evaluate the role of two-dimensional speckle tracking imaging (2DSTI) in detecting early changes of myocardial deformation in patients affected by thalassemia major (TM) and its relation with myocardial iron overload (MIO) detected by T2* cardiovascular magnetic resonance (CMR). We studied 28 TM patients (15 males, 37.4?±?10 years). All patients underwent CMR and echocardiography in the same day. Segmental and global T2* values were measured. Values of global longitudinal strain (GLS) were derived from the three apical views, while radial and circumferential strain were obtained as average strain from the short axis views at basal, mid and apical level. Six patients (21.4%) showed significant MIO (global heart T2*?<?20 ms). GLS showed a significant correlation with T2* values (R?=??0.49; P?=?0.001) and it was significantly lower in patients with a significant MIO than in those with no significant MIO (?18.3?±?2 vs. ?21.3?±?2.7, P?=?0.02). No significant difference was found for radial and circumferential strain in relation to the severity of MIO. Patients with impaired GLS (<?19.5%) had a significant higher risk of showing significant MIO (Odds-ratio-OR?=?17; 95%). GLS is related with global T2* in TM patients. Moreover, GLS can identify TM patients with severe MIO detected by CMR.  相似文献   
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We studied 60 patients who had survived the Mustard procedure for transposition of the great arteries, performed between the ages of 2 days and 24 months (mean 4.51 +/- 3.79). All patients were given a postoperative 24-hour dynamic electrocardiogram at 15 days, 1 year and 3 years and then every 2 years. Those who were found to have sinus node dysfunction during follow-up, were given a dynamic electrocardiogram every 3-6 months. The average follow-up period was 38.7 +/- 19.8 months, median 36. Sinus node dysfunction was detected during follow-up in 20 patients (33.3% of the total), 8 of whom had had a pacemaker inserted. Risk factors for late development of sinus node dysfunction were found to include prolonged cross-clamping of the aorta during surgery (P = 0.003), especially over 50 minutes (relative risk 3.5:1), and the presence of even transient sinus node dysfunction after surgery (P = 0.006). These observations suggest, first, that sinus node dysfunction may develop after the Mustard operation as a combined effect of extensive atrial surgery and a long period of myocardial ischemia and, second, that the presence of the disease immediately after the operation sometimes indicates that it will recur or persist during follow-up.  相似文献   
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BACKGROUND: Assessment of liver cell proliferation by immunodetection of proliferating cell nuclear antigen may predict regenerative potential and survival of liver and hepatocellular carcinoma risk in patients with chronic viral hepatitis. AIM: To evaluate proliferating cell nuclear antigen status and its clinical significance in a large cohort of patients with chronic viral hepatitis and different degree of liver damage by a computer assisted imaging analysis system. MATERIALS: Liver biopsies from 358 patients with chronic hepatitis (259 males, 49 years, 63% with hepatitis C infection, 27% with hepatitis B virus, 10% with multiple infections) were studied. METHODS: Proliferating cell nuclear antigen was localised by immunoperoxidase on microwave oven pre-treated formalin-fixed, paraffin embedded sections using PC10 monoclonal antibody. Proliferating cell nuclear antigen labelling index was calculated by an automated imaging system (Immagini e Computers, Milan, Italy). RESULTS: Mean proliferating cell nuclear antigen labelling index ranged from 0.1% for patients with minimal changes to 3.6% for those with cirrhosis and hepatocellular carcinoma. Overall, proliferating cell nuclear antigen labelling index was higher in males, in older patients, in multiple infections and in hepatitis C virus compared to hepatitis B virus related cases. By linear regression analysis, proliferating cell nuclear antigen labelling index correlated with older age, male gender; higher transaminase levels, hepatitis C virus, higher histological gradIng and staging: by multivariate analysis male gender, hepatitis C virus, higher grading and staging resulted as independent variables. Both hepatitis C virus or hepatitis B virus cirrhotics had similar liver cell proliferation rate but those with hepatitis B virus had higher prevalence of liver cell dysplasia with respect to those with hepatitis C virus. CONCLUSIONS: Proliferating cell nuclear antigen labelling index was a reliable assay for assessing liver cell proliferation rate in patients with chronic viral hepatitis and correlated with liver disease severity  相似文献   
55.
OBJECTIVE: Carotid arterial compliance is reduced with age in sedentary estrogen-deficient women, contributing to the development of cardiovascular disorders. We determined the effects of regular aerobic exercise, hormone replacement therapy (HRT), and their interaction on carotid arterial compliance using a combination of cross-sectional and intervention study designs. METHODS: Cross-sectionally, we studied three groups of healthy postmenopausal women (50-80 years): 20 sedentary not taking HRT; 24 sedentary taking HRT; and 14 endurance-trained not taking HRT; and 11 sedentary premenopausal controls (20-37 years). In the intervention study, 12 sedentary postmenopausal women (58+/-3 years) who were taking HRT were studied before and after participation in a 3-month aerobic exercise (walking) program. Carotid arterial compliance was measured via simultaneous common carotid artery ultrasound imaging and applanation tonometry. RESULTS: Cross-sectional study. Carotid arterial compliance was lower (P<0.001) in all three postmenopausal groups compared with premenopausal women. Among the postmenopausal groups, arterial compliance was 33-43% higher in the sedentary HRT and endurance-trained women than in their sedentary estrogen-deficient peers. Intervention study. Arterial compliance increased (P<0.05) by approximately 40% to levels that were no longer different than premenopausal women. CONCLUSIONS: HRT use and regular aerobic exercise are associated with augmented carotid arterial compliance in healthy postmenopausal women. Moderate, short-term aerobic exercise can restore carotid arterial compliance in previously sedentary postmenopausal women taking HRT.  相似文献   
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The case of a 59-year-old man with corrected transposition of the great arteries (CTGA) is reported. This anomaly is rare in adult patients, uncommon in patients over 50. Most of the cases with CTGA are diagnosed in childhood because of associated cardiac abnormalities. When isolated or complicated by other mild anomalies, CTGA can cause no symptoms until adult life or can even go unrecognized. However, most of these patients present with congestive heart failure when they are 40 or 50 years old. Our patient was admitted to the hospital because of heart failure. Cardiac catheterization and selective angiography demonstrated a CTGA associated with severe pulmonary valve stenosis. The case here reported shows that CTGA even when associated with other cardiac abnormalities, can be a relatively benign lesion, and can be revealed in adult life by signs of cardiac failure.  相似文献   
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BackgroundAtherosclerotic cardiovascular disease is a chronic inflammatory condition. Thiazolidinediones (TZDs) are used to enhance sensitivity to insulin and have demonstrated a protective effect over a variety of cardiovascular markers and risk factors. Controversially, the TZDs are associated with the development of heart failure. Thus, lines of research have invested in the search for new molecules in order to obtain more selective and less harmful treatment alternatives for the pathogenesis of atherosclerosis and its risk factors.MethodsAnimals were fed a diet rich in fat for 10 weeks. In the last 2 weeks, animals received either pioglitazone, LPSF/GQ-02, or LPSF/GQ-16 daily through gavage. At the end of the treatment, blood was collected for biochemical analysis and the aortas were dissected for subsequent analyses.ResultsNo changes in the blood lipid profile were found following the use of the drugs in comparison to the control. However, the new thiazolidine derivatives were more efficient in improving insulin resistance in comparison to pioglitazone and the control group. Morphometric analyses revealed that neither pioglitazone nor LPSF/GQ16 led to satisfactory effects over atherosclerosis. However, LPSF/GQ-02 led to a reduction in area of the atherosclerotic lesions. Ultrastructural analyses revealed extensive degeneration of the endothelium and an increase in apoptotic cells in the subendothelial space following the use of pioglitazone and LPSF/GQ-16. However, LPSF/GQ-02 caused minimal cell alterations in the aortic endothelium. Regarding markers, endothelial nitric oxide synthase (eNOS) and matrix metalloproteinase 9 (MMP-9), LPSF/GQ-16, and pioglitazone exerted similar effects, increasing the expression of MMP-9, and had no effect on the expression of eNOS compared with the control group. On the other hand, LPSF/GQ-02 was effective in reducing the expression of MMP-9 and increased eNOS significantly.ConclusionsThe results suggest that the new thiazolidine derivative LPSF/GQ-02 is a promising candidate for the treatment of atherosclerosis.  相似文献   
60.
Ciliopathies are genetically heterogeneous disorders characterized by variable expressivity and overlaps between different disease entities. This is exemplified by the short rib‐polydactyly syndromes, Jeune, Sensenbrenner, and Mainzer‐Saldino chondrodysplasia syndromes. These three syndromes are frequently caused by mutations in intraflagellar transport (IFT) genes affecting the primary cilia, which play a crucial role in skeletal and chondral development. Here, we identified mutations in IFT140, an IFT complex A gene, in five Jeune asphyxiating thoracic dystrophy (JATD) and two Mainzer‐Saldino syndrome (MSS) families, by screening a cohort of 66 JATD/MSS patients using whole exome sequencing and targeted resequencing of a customized ciliopathy gene panel. We also found an enrichment of rare IFT140 alleles in JATD compared with nonciliopathy diseases, implying putative modifier effects for certain alleles. IFT140 patients presented with mild chest narrowing, but all had end‐stage renal failure under 13 years of age and retinal dystrophy when examined for ocular dysfunction. This is consistent with the severe cystic phenotype of Ift140 conditional knockout mice, and the higher level of Ift140 expression in kidney and retina compared with the skeleton at E15.5 in the mouse. IFT140 is therefore a major cause of cono‐renal syndromes (JATD and MSS). The present study strengthens the rationale for IFT140 screening in skeletal ciliopathy spectrum patients that have kidney disease and/or retinal dystrophy.  相似文献   
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