Characterization of recombinant plasminogen activator production by primate endothelial cells transduced with retroviral vectors

Retroviral vector-mediated expression of plasminogen activators (PAs) from endothelial cells (ECs) has been proposed as a potential therapeutic approach for intravascular thrombosis. To define the potential for gene transfer to increase fibrinolytic activity in a primate system, baboon ECs were transduced with retroviral vectors expressing wild-type and glycosylphosphatidylinositol-anchored urokinase, as well as wild-type and serpin-resistant tissue PA (t-PA). Expression of either t-PA or urokinase was increased by one log over baseline levels. There was no specific effect of either t-PA or urokinase overexpression on endogenous t-PA, urokinase, or PA inhibitor 1 (PAI-1) expression. Recombinant urokinase could be anchored to the cell surface at a level eight-fold above that of receptor-bound urokinase. The majority of secreted urokinase accumulated in conditioned medium as a free proenzyme, whereas both wild-type and serpin-resistant t-PA accumulated almost exclusively in complexes with PAI-1. In most but not all of the assays, the urokinase vectors conferred PA activity above that of the t-PA vectors. These data show that PA synthesis and activity are specifically increased subsequent to retroviral vector-mediated gene transfer in primate ECs. However, definition of an optimal PA vector will require in vivo experimentation.     

脱抗原牛角胎骨移植家兔后的特异性免疫反应

目的：研究脱抗原水牛胎移植后的免疫排斥反应和成骨效应。方法：以日本大耳白兔为动物模型，分别植入经30％，H2O2，0．6mol/L HCl脱抗原脱钙，30％H2O2脱抗原不脱钙2种温和方法处理的水牛角胎至兔佐侧肢骨缺损处，体外检测外周血特异性T淋巴细胞转化率和ELISA检测血清特异性抗角胎IgG抗体。结果：脱抗原脱钙处理显著地降低了角胎的抗原性，与对照相比，未见受体对移植物产生显著的特性细胞和体液免疫反应（P＞0．05），尤其是脱抗原不脱钙角胎效果更佳，两者成骨效果良好。结论：脱抗原角胎是一种免疫原性低，成骨效果好，来源方便的骨移植材料。     

Anticoagulant therapy in children with prosthetic valves

The purpose of this study was to evaluate the effectiveness and complications of several types of anticoagulant therapy in children with prosthetic valves. During a 7-year period ending April 1985, 130 children aged 1 to 19 years underwent left-sided valve replacement. Operative mortality was 3%, 5%, and 9%, respectively, for aortic, mitral, and aortic and mitral valve replacement. Among the 123 survivors, 32 (26%) had had aortic, 71 (58%) had had mitral, and 20 (16%) had had aortic and mitral valve replacement. Follow-up ranged from 2 months to 8.2 years, a total of 544 patient-years. The survivors were divided into three groups based on anticoagulant treatment: warfarin sodium, aspirin plus dipyridamole, and no anticoagulants. Among the patients who had aortic valve replacement, thromboembolic complications developed in 2.5% (2.5/100 patient-years) of the aspirin plus dipyridamole group and 5% of the group given no anticoagulants. Only the warfarin group (4%) experienced bleeding complications. Among the patients having mitral valve replacement, thromboembolic complications developed in 4% of the warfarin group, 3% of the aspirin plus dipyridamole group, and 11% of the no anticoagulant group. In addition, 2% of patients in the warfarin group experienced severe bleeding. Two fatal cerebrovascular accidents occurred, both in the aspirin plus dipyridamole group. Patients who received a mitral heterograft were not prescribed any anticoagulant medications, and no thromboembolic complications developed. Among patients having double-valve replacement, complications developed in 5% of the warfarin group and 27% of the group given no anticoagulants.(ABSTRACT TRUNCATED AT 250 WORDS)     

Medial brachial fascial compartment syndrome: anatomic basis of neuropathy after transaxillary arteriography

The authors reviewed their experience with 320 transaxillary arteriograms, as well as the English-language literature on neuropathy complicating transaxillary arteriography. Three of their patients had median and ulnar motor and sensory nerve injury, and six others had only sensory involvement. The occurrence or severity of nerve injury did not correlate well with the size or presence of an observable axillary or arm hematoma. Dissection of the axillae and arms of 25 human cadavers revealed a tough medial brachial fascial compartment (MBFC) outside a thin axillary sheath. The median and ulnar nerves were within the MBFC at an arterial puncture site just lateral to the anterior axillary fold. The radial and musculocutaneous nerves exited the MBFC more proximally. The different levels at which the major nerves of the brachial plexus exit the MBFC explain the anatomic distribution of the nerve injuries associated with compression by a hematoma after transaxillary arteriography.     

AIDS-related lymphomas: evaluation by abdominal CT

Recent evidence indicates that individuals with acquired immunodeficiency syndrome (AIDS) or those at high risk for AIDS have an increased occurrence of lymphoma. AIDS-related lymphomas (ARLs) often present with an advanced stage of disease and highly malignant histologic subtypes. This study reviewed the abdominal computed tomographic (CT) findings in 29 patients with ARL, including ten with Hodgkin disease (HD) and 19 with non-Hodgkin lymphoma (NHL). Focal splenic and hepatic involvement was more common in both AIDS-related HD (10%) and NHL (26%) than reported in the non-AIDS population. In addition, mesenteric lymphadenopathy was demonstrated in 20% of patients with AIDS-related HD, compared with less than 5% in non-AIDS patients. In this series, patients with NHL had pelvic nodal masses in 37%, bowel involvement in 26%, and renal lesions in 11%. The authors conclude that ARLs are highly aggressive neoplasms that often present with atypical features compared with lymphomas in other patients. Potential problems in the CT interpretation of ARL for homosexual men are discussed.     

Biliary dilatation: defining the level and cause by real-time US

In a 15-month period, 110 patients with subsequently proved biliary dilatation were evaluated with ultrasound (US). The level of dilatation was defined as pancreatic, suprapancreatic, or at the level of the porta hepatis. Causes of dilatation included pancreatitis, choledocholithiasis, neoplasm, and stricture. The distal duct was examined initially on transverse scans obtained with the patient in a semierect right posterior oblique position; the proximal duct was then examined on longitudinal scans obtained with the patient in a supine left posterior oblique position. When this scanning technique was used, US indicated the level of dilatation in 91.8% of cases and suggested the correct cause in 70.9%. Because this approach markedly improves US visualization of the intrapancreatic bile duct, distal obstructing lesions, which are the most common, can be optimally examined.