放射性NiTi合金血管内支架可行性及安全性的实验观察

目的：观察2．3μCi的放射性NiTi合金血管内支架植入正常兔腹主动脉后的安全性及可行性。方法：将16只兔随机分为放射性支架组(n＝8)及非放射性支架组(n＝8)，分别于腹主动脉内植入放射性NiTi合金血管内支架和不具有放射性的NiTi合金血管内支架。于3个月后处死两组动物，肉眼观察支架局部有无血栓形成，光镜及透射电镜观察支架局部血管的结构改变；生化法测定肝功、肾功；骨穿涂片观察骨髓象。结果：放射性支架组新生血管内膜厚度明显低于非放射性支架组，新生血管内膜平滑肌细胞(SMCs)明显减少，中膜的厚度和SMCs与非放射组无显著性差异，两组新生血管内膜均完全内皮化，无血栓形成；两组的谷丙转氨酶、谷草转氨酶和尿素氮、肌酐均无显著性差异；两组动物的骨髓增生均正常。结论：2．3μCi的放射性NiTi合金血管内支架可减少血管新生内膜增生，对血管中膜、邻近重要脏器及骨髓造血无影响，可安全应用。     

Intracranial Angioplasty and Stenting in the Awake Patient

BACKGROUND AND PURPOSE: Endovascular treatment for intracranial atherosclerosis is evolving, but complications remain an issue. Most interventions are performed under general anesthesia, preventing intraprocedural clinical evaluations. We describe our approach to intracranial angioplasty and stenting, using local rather than general anesthesia, and intraprocedural neurological assessment. METHODS: We prospectively collected procedural and outcome information on all patients undergoing intracranial angioplasty and stenting. Patients underwent interventions under local anesthesia with mild intravenous sedation or analgesia only if needed. Intraoperative neurological evaluations were performed, and symptomatology was used to guide the interventional technique. RESULTS: Forty-eight arteries in 40 patients with a mean age of 65.2 years were treated. Thirty-two anterior and 16 posterior circulation segments were treated. Technical success was achieved in 100% of patients with reduction of the mean pretreatment stenosis from 85 +/- 8.6% to 7 +/- 10.1%. Stents were deployed in 40 segments; five patients were treated with drug-eluting stents. The cobalt-chromium coronary stents were the easiest to deliver. Thirty-seven patients were treated under local anesthesia and, of those, 61.4% experienced intraprocedural symptoms that led to some alteration of the interventional technique. Headache was the most common symptom, and, when persistent, it heralded the occurrence of subarachnoid hemorrhage. There were seven total neurological complications, but only five (10.5%) led to permanent morbidity (4 strokes) or mortality (1 death). CONCLUSIONS: Intracranial angioplasty and stenting can be successfully performed using coronary techniques and equipment including drug-eluting stents. Local anesthesia permits neurological evaluations and often leads to the adjustment of the interventional technique, potentially making the procedure safer.     

Covered metal stent for tumor obstruction of efferent loop recurrence after gastrectomy

Reports the case of a 60-year-old woman who underwent R2 total gastrectomy, and subsequent palliation of painful symptom recurrence via a membrane-covered metal stent. Received: 13 June 1996/Accepted: 31 July 1996     

Is it possible to prevent bacterial adhesion onto ureteric stents?

The aim of this study was to determine whether the use of bactericidal coatings or immersion in antibiotic solution reduces or prevents bacterial adhesion onto ureteric stents. Precut segments of full silicone, silver-coated and hydrogel-coated ureteric stents were incubated with two uropathogenic bacterial strains with and without previous immersion in antibiotic solution. Tobramycin, ceftriaxone and ciprofloxacin solutions were used, as these antibiotics are commonly administered for the prophylaxis and treatment of urinary tract infection (UTI). Microbiological analysis showed that immersion of ureteric stents in ceftriaxone and ciprofloxacin yielded a significant reduction of bacterial adhesion, whereas immersion in tobramycin did not. The surface material of the stents had no direct influence on bacterial adhesion. In this experimental study, neither the silver nor the hydrogel coat reduced bacterial adhesion onto ureteric stents whereas immersion in a suitable antibiotic solution significantly reduced and even prevented this phenomenon, probably due to the adhesion of the antibiotic onto the stent surface. Prevention of bacterial adhesion onto ureteric stents is essential to reduce the risk of UTI in connection with these devices.     

组织工程支架在犬急性脊髓损伤修复中应用的初步研究

目的探讨携带神经干细胞的聚碳酸亚丙酯[poly（propylene carbonate），PPC]可降解支架移植在犬脊髓急性损伤后修复中的作用。方法制作犬T13脊髓左侧半切损伤模型。将实验动物随机分为3组：细胞支架组在损伤后1周时将填充神经干细胞的PPC可降解支架植入损伤区．支架组只植入支架，对照组不作移植。8周后观察支架的组织反应、降解情况及神经干细胞的迁移分化和脊髓轴突再生情况。结果支架部分降解，管腔内未见瘢痕侵入。神经干细胞向支架邻近部位广泛迁移、扩散，并分化为3种神经细胞表型。神经丝蛋白（NF）及髓鞘碱性磷酯蛋白（MBP）免疫组化显示细胞支架组脊髓损伤区邻近部位的继发损害较其他组轻。结论携带神经干细胞的PPC可降解支架在犬脊髓组织中无明显组织反应．能够抵御瘢痕侵入：其携带的神经干细胞能够整合入邻近脊髓组织并起到一定保护作用。     

Postlaminectomy arteriovenous fistula masked by stenosis of the inferior vena cava

Discovery of a postlumbosacral discectomy fistula between the right iliac artery and vein was obscured by an associated severe stricture of the infrarenal inferior vena cava in a 49-year-old man. During venous stenting for treatment of peripheral edema, the fistula was suspected because of faint pulsatile right iliac vein flow and increased O₂ saturation of the venous blood. The suspicion was confirmed on subsequent iliac arteriography. Surgical closure of the fistula with arterial interposition grafting was then performed. The patient improved substantially.     

经皮冠状动脉内支架植入术对外周血单核细胞NF-κB活性的影响

目的:探讨经皮冠状动脉内支架植入术是否激活外周血单核细胞(PBMCs)中核因子κB(NF-κB)活性的表达.方法:选择NF-κB基线时呈阴性反应的稳定型心绞痛患者50例,其中单纯造影组22例,支架治疗组28例.分别于冠脉造影或支架术后4 h及术后第1,2,3 d留取全血抗凝标本;采用凝胶电泳迁移率实验(EMSA)测定PBMCs中NF-κB的活性.结果:支架术程中NF-κB活性呈动态变化,于术后1 dNF-κB活性显著性升高呈阳性反应,术后2 d NF-κB活性达峰值,术后3 d NF-κB活性有下降,但仍保持在高水平表达状态.而造影组患者则没有NF-κB活性变化.结论:冠状动脉内支架术激活外周血单核细胞NF-κB活性.     

Management of malignant biliary stricture with self-expanding metallic stent

Background: Self-expanding metallic mesh stents are designed to remain patent longer than polyethylene (PE) stents, which generally clog in 3 to 4 months. Though more expensive, metal stents may therefore be a better choice for malignant strictures. Methods: From January 1991 to October 1995, we performed ERCP in 212 patients with malignant or benign strictures, and 34 ultimately had insertion of a metallic stent. These stents were placed by the percutaneous transhepatic route in 17 patients and endoscopically in 17. Results: Metallic stent insertion was successful in each case and relieved the preoperative jaundice and cholangitis. There were no procedure-related deaths; complications were pancreatitis (one) and hemorrhage (one). Overall stent patency was 6.2 months. Three of 34 stents occluded due to tumor ingrowth at 3, 4.5, and 8 months and were treated by placing a new PE stent through the blocked metal stent. The remaining 31 stents remained patent until patient death (n= 15, mean survival = 4.9 months) or are still open (n= 16, mean patency = 12.2 months). Conclusions: Self-expanding metal stents provide effective palliation of malignant biliary strictures and should be considered an alternative to open surgery. Metal stents remain patent much longer than PE stents and usually a single session of metal stenting can palliate biliary obstruction for life. Received: 20 March 1996/Accepted: 9 May 1996