Reconstruction of the right ventricular outflow tract with bovine pericardial monocusp patch

From November 1980 to May 1982, 19 patients underwent surgery in this institution for right ventricular outflow tract obstruction. Surgery was performed by placing a bovine pericardial monocusp patch across the pulmonary annulus. There was one hospital death (5.3%), and one late death. The follow-up ranged from 24 to 42 months (mean 32.5 +/- 5.3 months; total, 552 patient months). The condition of the remaining 17 patients is good. Repeat cardiac catheterization was performed in 11 patients and revealed that the right ventricular/pulmonary artery systolic gradient was reduced to 13.7 +/- 9.7 mm Hg postoperatively. Angiography showed a freely mobile, thin valve cusp. No calcification, aneurysmal dilatation, or shrinkage of the monocusp patch was observed. Our experience suggests that right ventricular outflow tract reconstruction with bovine pericardial monocusp patches can be safely performed with good hemodynamic results.     

Assessment of linkage and association of 13 genetic loci with bone mineral density

Bone mineral density (BMD), an important risk factor for osteoporosis, is a complex trait likely affected by multiple genes. The linkage and/or association of 13 polymorphic loci of seven candidate genes (estrogen receptor alpha [ERα] and beta [ERβ], calcium-sensing receptor, vitamin D receptor, collagen type 1α1, low-density lipoprotein [LDL] receptor-related protein 5 [LRPS], and transforming growth factor β1) were evaluated in 177 southern Chinese pedigrees of 674 subjects, with each pedigree identified through a proband having a BMD Z score of −1.28 or less at the hip or spine. A suggestive linkage was detected between the IVS1-351A/G polymorphism of ERα and spine BMD, and between the 1082G/A, 1730G/A, and D14S1026 polymorphisms of ERβ and BMD at both spine and hip. The quantitative transmission disequilibrium test (QTDT) detected total family association between 1730G/A of ERβ and BMD at spine and hip; between D14S1026 of ERβ and hip BMD; and between the 266A/G and 2220C/T polymorphisms of LRP5 and hip BMD. Similar total family associations were detected when only the females were analyzed. In addition, the IVS1-397T/C polymorphism of ERα was associated with spine BMD, and the 266A/G and 2220C/T polymorphisms of LRP5 were associated with femoral neck BMD in the females. A within-family association was detected with the IVS1-397T/C polymorphism of ERα, and the 266A/G and 2220C/T polymorphisms of LRP5 in the females. The effect of each polymorphism on BMD variance ranged from 1% to 4%. In conclusion, ERα, ERβ and LRP5 are important candidate genes determining BMD variation, especially in females.     

中国南方人群腰椎间盘退变的影像学和流行病学研究

 目的 评估中国南方都市人群中腰椎间盘退行性变化的程度、发生率及在不同椎间节段的分布状况。方法 共有1 724例志愿者参加了该研究,男662例,女1062例;年龄18~85岁,平均为38.04岁。对所有参加者进行了影像学检查、临床体格检查和症状学评分。采用1.5 T的磁共振系统进行脊柱扫描(腰椎T₂矢状位序列成像)。在所得MR图像的基础上对腰椎间盘退变进行评分。评估每个腰椎节段的许莫氏结节(Schmorl nodes)、高信号区(HIZ)和骨髓信号的改变。结果 许莫氏结节的发生与性别相关,许莫氏结节在男性中发生率更高。卡方检验结果显示许莫氏结节、骨髓信号改变和高信号区三种影像学表现与腰椎间盘退变的相关性依次增强,均有统计学意义。高信号区和骨髓信号改变与年龄呈明显相关 。许莫氏结节和高信号区在腰椎中的分布规律为：许莫氏结节自上(头端)至下(尾端)呈降序分布;椎间盘高信号区自上至下呈升序分布。腰椎间盘退变评分(DDD分数)与身体质量指数呈正相关 。DDD评分结果在男女性别间无明显差异。腰椎间盘节段自上(头端)至下(尾端)的退变发生呈持续升高趋势。腰椎间盘退变在男女性别之间有一定程度的差异。腰椎间盘退变在年轻人群中总体发生率高,男性为35.3%,女性为33.9%。结论 腰椎间盘退变在中国南方人群呈高发状态,特别是年轻成人,25~35岁的男性比女性更易患腰椎间盘退变,身体质量指数与腰椎间盘退变明显相关。     

Late temporal lobe necrosis in patients with nasopharyngeal carcinoma: evaluation with combined multi-section diffusion weighted and perfusion weighted MR imaging

Late temporal lobe necrosis is a well-known and serious complication in patients with nasopharyngeal carcinoma (NPC) following radiotherapy. Owing to the close proximity to the skull base, the medial temporal lobes are inevitably included in the target volume of irradiation. Patients with NPC provide a unique opportunity in study of delay radiation effect in normal human brain. The objective of this study was to evaluate late temporal lobe radiation injury by combined multi-section diffusion weighted and perfusion weighted MR imaging. We prospectively studied 16 patients with typical clinical symptoms of late temporal lobe necrosis or other abnormalities in the temporal lobes incidentally detected by conventional MR imaging. All patients had a previous history of radiotherapy for histologically proven NPC. Conventional T1- and T2-weighted images, fast gradient echo with echo-planar diffusion-weighted and perfusion-weighted MR imaging were performed. Apparent diffusion coefficient (ADC) map and relative cerebral blood volume (rCBV) map were computed via commercially available software. MR diffusion and perfusion images were then analyzed and graded by two independent observers with focusing on the diffusion and perfusion mismatch. The temporal lobe lesions displayed marked high diffusion on the ADC map. The rCBV map also revealed marked hypoperfusion in these temporal lobe lesions in all patients. The areas of abnormality on the rCBV map were significantly larger than the lesions on the ADC map in 14 patients (observer 1) and 13 patients (observer 2). Since late temporal lobe necrosis is probably caused by damage of the endothelium of vessels and ischemia, perfusion and diffusion mismatch might imply injured tissue but potentially salvageable brain tissue. A mismatch may be potentially used to predict the response to treatment in-patients with late temporal lobe necrosis.