Malignant glioma-derived soluble factors regulate proliferation of normal adult human astrocytes.

Malignant gliomas are characteristically surrounded by marked gliosis. To assess whether glioma-derived products contribute to the proliferation of astrocytes, a feature of the gliosis response, we evaluated the influence of culture supernatants from malignant human glioma lines and tumor cyst fluids collected from two patients with glioblastoma multiforme on the proliferation of non-transformed adult human astrocytes. Both the culture supernatants and cyst fluids significantly increased DNA synthesis in astrocytes as assessed by a double immunofluorescence glial fibrillary acidic protein-bromodeoxyuridine technique. The net proliferative effect mediated by glioma cell line supernatants was tumor growth phase-dependent, being preferentially expressed during the logarithmic phase of glioma cell growth. Specific growth factor molecules and cytokines known to be secreted by gliomas (epidermal growth factor, fibroblast growth factor, platelet-derived growth factor, transforming growth factor-beta, interleukin-6, and tumor necrosis factor-alpha) could not reproduce the mitogenic effects of the glioma-derived soluble factors. Cytokines which can induce DNA synthesis by adult human astrocytes in vitro, gamma-interferon and interleukin-1, were not detected in the culture supernatant of glioma lines used in this study. In conjunction with the documented effects of glioma products on endothelial and lymphoid cells, the current study suggests that soluble glioma products can contribute to the production of surrounding gliosis observed in vivo.     

Cervical esophago-esophageal anastomosis.

We describe our results with cervical esophagoesophageal anastomosis. This approach has been used with success in 4 patients. It has the advantage of avoiding esophagectomy in patients with benign disease and allows restoration of esophageal continuity in patients having limited options for esophageal replacement.     

Oesophageal dissection after thrombolytic treatment for myocardial infarction.

A 62 year old woman admitted with a history suggesting acute myocardial infarction had thrombolytic treatment with anisoylated plasminogen-streptokinase activator complex, which resulted in submucosal haemorrhage in the oesophagus; this caused dissection of the wall of the oesophagus and complete dysphagia. The haematoma resolved spontaneously, leaving behind a diverticulum, with reduced peristalsis and delayed emptying but no obstruction.     

The future of cardiovascular imaging and non-invasive diagnosis

Advances in medical imaging now make it possible to investigate any patient with cardiovascular disease using multiple methods which vary widely in their technical requirements, benefits, limitations and costs. The appropriate use of alternative tests requires their integration into joint clinical diagnostic services where experts in all methods collaborate. This statement summarises the principles that should guide developments in cardiovascular diagnostic services.This paper is published simultaneously in the European Heart Journal (2006;27:1750–1753) and in the European Journal of Echocardiography (2006;7:268–273).     

未破裂脑动脉瘤的治疗选择

未破裂脑动脉瘤的处理存在争议。由于其自然史尚未完全明确,因此最佳的治疗策略也不清楚。目前对未破裂脑动脉瘤处理的共识包括观察、显微手术夹闭和血管内治疗。用于随访已知未破裂脑动脉瘤的方法学也有争议,可能取决于经治医生的偏好。大多数动脉瘤由神经外科医师和介入神经放射科医师处理,但未破裂动脉瘤通常是由神经科医师在对患者进行其他神经系统疾病的筛查时首先发现的。因此,关于何时对患者进行筛查和如何对未破裂动脉瘤采取最佳处理的知识将对其日常医疗实践有直接的影响。未破裂动脉瘤经常导致包括缺血事件、癫和头痛在内的其他神经系统症状,这些症状可能促进更积极的干预治疗。由于缺乏设计完善真正基于人群的研究或随机试验,因此目前的最佳处理必须以现有文献和每例患者当时的具体情况为根据。     

Gastric motility measurement by MRI

The motor mechanisms associated with gastric emptying of nutrient liquids are unclear. Gastric emptying and motility were determined in seven healthy volunteers using an MRI technique following ingestion of 500 ml of (1) 10% and (2) 25% dextrose labeled with 1 mM Gd-DOTA. Emptying was determined with transaxial scans and motility during fast coronal scans 1.2 sec apart. Emptying was slower after ingestion of 25% dextrose. Following both meals, proximal gastric diameter remained relatively constant, while antral contractile frequency and depth varied markedly. These variations were greater after 10% dextrose. These studies suggest that antral motility changes contribute to slowing of gastric emptying by nutrient meals.     

Gd-DOTA as a gastrointestinal contrast agent for gastric emptying measurements with MRI

Current MR meal markers may interfere with gastric motility and secretion restricting the use of MRI in the measurement of gastric physiology. We therefore evaluated Gd-DOTA as a liquid phase marker, in vitro by determining dissociation, and adherence to the solids, and in vivo by simultaneous MRI (0.35 T scanner, multiple T₁-weighted sections of the upper abdomen) and double indicator (perfusion marker PEG 4000, meal marker ^99mTc-DTPA) measurements of emptying and secretion, following ingestion of 500 ml 10% glucose. In vitro Gd-DOTA was stable at a pH > 2 with < 2% dissociation at 24 h during incubation with HCI. Dissociation during incubation with HCI was linearly dependent on H⁺ concentration (0.77 < pH < 2.02). Less Gd-DOTA was absorbed onto the solid phase than ^99mTc-DTPA (25% cf 36%). in vivo Gd-DOTA marked gastric contents provided strong positive contrast. Similar emptying curves were observed with both MRI and double-indicator techniques (r = 0.987, P < 0.001). Gd-DOTA has the potential to be a useful liquid phase contrast agent in MR studies on gastric function.