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OBJECTIVE: Reoperative cardiac surgery after previous coronary artery bypass grafting represents a surgical challenge due to the potential for injury to patent coronary grafts, aorta or right ventricle. Standard preoperative imaging using a coronary angiogram and chest radiograph (CXR) often results in inaccurate assessment of mediastinal anatomy. We aimed to evaluate 3D volume rendered computed tomographic imaging as an adjunct to standard preoperative assessment of patients requiring cardiac surgery in whom coronary artery revascularization had been performed in the past. METHODS: Between January 2003 and January 2004, 33 patients with previous coronary revascularization referred for reoperative cardiac surgery underwent preoperative 3D CT imaging in order to optimize the surgical approach. The mean age in this patient population was 72+/-8 years. The combined evaluation of CXR and conventional angiography offered incomplete insight into pertinent mediastinal topography in 85% of patients (28/33). RESULTS: The correlations for distances of the left internal mammary artery (LIMA) to left anterior descending artery (LAD) graft from the midline and posterior sternum obtained by CT angiography (CTA) and CXR were poor, R=0.56 and 0.49, respectively. The correlation coefficients for distances between the right ventricle and the aorta to the sternum obtained by the same methods were similarly marginal, 0.58 and 0.48, respectively. The correlation coefficients for distances between the LIMA to LAD, circumflex and right coronary artery grafts from the midline obtained by CTA and conventional angiography were 0.54, -0.13 and 0.43, respectively. In seven patients (21%) the surgical strategy was modified based on the location of patent grafts in the mediastinum. The hospital mortality was 17% (5/29). Intraoperative injuries to vital structures were encountered in two patients (7%). No injuries to patent LIMA or the aorta were encountered. CONCLUSIONS: The 3D CT imaging technique is useful in defining the optimal surgical strategy for reoperative cardiac surgery. We found that CTA is superior to CXR and conventional angiography in defining the position of patent grafts and vital structures in relation to the midline and posterior sternum. Preoperative mapping of patent coronary grafts and other vital mediastinal structures reduces the morbidity of the reoperation through modification of surgical approaches.  相似文献   
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Dietary polyphenols promote cardiometabolic health and are linked with long-chain polyunsaturated fatty acids in plasma phospholipids (LC-PUFA). The FADS2 polymorphisms are associated with LC-PUFA metabolism and overweight/obesity. This 4-week study examined the link between polyphenol intake, FADS2 variants (rs174593, rs174616, rs174576) and obesity in 62 overweight adults (BMI ≥ 25), allocated to consume 100 mL daily of either: Aronia juice, a rich source of polyphenols, with 1177.11 mg polyphenols (expressed as gallic acid equivalents)/100 mL (AJ, n = 22), Aronia juice with 294.28 mg polyphenols/100 mL (MJ, n = 20), or nutritionally matched polyphenol-lacking placebo as a control (PLB, n = 20). We analyzed LC-PUFA (% of total pool) by gas chromatography and FADS2 variants by real-time PCR. Four-week changes in LC-PUFA, BMI, and body weight were included in statistical models, controlling for gender and PUFA intake. Only upon AJ and MJ, the presence of FADS2 variant alleles affected changes in linoleic, arachidonic, and eicosapentaenoic acid (EPA). Upon MJ treatment, changes in EPA were inversely linked with changes in BMI (β= −0.73, p = 0.029) and weight gain (β= −2.17, p = 0.024). Only in subjects drinking AJ, the link between changes in EPA and anthropometric indices was modified by the rs174576 variant allele. Our results indicate the interaction between FADS2, fatty acid metabolism, and polyphenol intake in overweight subjects.  相似文献   
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Considering the relatively high heritability of schizophrenia and the fact that it significantly reduces the reproductive fitness of affected individuals, it is not clear how the disorder is still maintained in human populations at a disproportionally high prevalence. Many theories propose that the disorder is a result of a trade‐off between costs and benefits of the evolution of exclusively human adaptations. There have also been suggestions that schizophrenia risk alleles are accompanied with increase in fitness of affected persons or their relatives in both past and current social contexts. The discoveries of novel schizophrenia‐related genes and the advancements in comparative genomics (especially comparisons of the human genome and the genomes of related species, such as chimpanzees and extinct hominids) have finally made certain evolutionary theories testable. In this paper, we review the current understanding of the genetics of schizophrenia, the basic principles of evolution that complement our understanding of the subject, and the latest genetic studies that examine long‐standing evolutionary theories of schizophrenia using novel methodologies and data. We find that the origin of schizophrenia is complex and likely governed by different evolutionary mechanisms that are not mutually exclusive. Furthermore, the most recent evidence implies that schizophrenia cannot be comprehended as a trait that has elevated fitness in human evolutionary lineage, but has been a mildly deleterious by‐product of specific patterns of the evolution of the human brain. In other words, novel findings do not support previous hypotheses stating that schizophrenia risk genes have an evolutionary advantage.  相似文献   
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Cardiac rhabdomyomas are common in tuberous sclerosis. We report a child who developed rhabdomyoma related arrhythmia refractory to antiarrhythmic drug therapy. Reversion of the atrial ectopic tachycardia was achieved with mammalian target of rapamycin pathway (mTOR) inhibitor sirolimus. As per our knowledge, this is the first time that sirolimus has been successfully used in this setting.  相似文献   
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