Antireflux biliary stents: Are they the solution to stent occlusions?

Endoscopic insertion of plastic or metal stents is a wellestablished treatment for malignant biliary obstruction. The major limitation of this technique is stent occlusion. Duodenobiliary reflux has been considered a key contributor to stent occlusion. The presence of plant fibers in 35% to 60% of occluded stents on confocal laser microscopy has further confirmed the presence of reflux when the stent is placed across the papilla. Antireflux stents address this problem by allowing normal antegrade flow but preventing reflux. Recent studies comparing these antireflux stents with the standard Tannenbaum stents have shown significantly prolonged patency. Although initial results are encouraging, larger randomized trials are required to establish efficacy.     

人骨关节炎滑膜组织cDNA文库的构建及分析

目的:构建骨关节炎滑膜组织的cDNA文库,为筛选与骨关节炎的发生特异相关的基因及探讨骨关节炎发病机制奠定基础。方法:实验于2006-01/10在深圳市人民医院骨关节科完成,选取骨关节炎患者滑膜,以Trizol一步法从骨关节炎滑膜组织中提取总RNA,分离纯化mRNA,反转录合成双链cDNA,以pBlueScriptII为载体,构建关节炎滑膜组织cDNA文库,对随机挑取的克隆进行鉴定。结果:①总RNA及mRNA的质量:总RNA经分光光度计测定,测得mRNA的A260nm吸光度值为0.245,平均得率为0.45g/L,A260nm/A280nm=1.84,无DNA、蛋白质及小分子污染。符合建库要求。②cDNA的合成及分析:10μg mRNA反转录合成cDNA,合成的cDNA大小为0.5￣9.0kb,且主要集中在1.0￣2.0kb之间。③文库的鉴定:将50ng的cDNA与质粒载体pBlueScriptII连接过夜,采用电转化法转化受体菌DH5A,经稀释铺板测定原始文库的滴度为1.45×109pfu/L,总克隆数为4.6×105,重组率为96.2%,扩增后文库总滴度为6.4×1012pfu/L,插入片段多分布在0.5～2.6kb之间。结论:构建关节炎滑膜组织cDNA文库具有较好的库容量、较高的重组率以及较大的插入片段,为克隆关节炎相关功能基因的研究奠定了基础。     

Asymptomatic chronic traumatic aortic valve perforation with severe aortic regurgitation

Here, we present a young asymptomatic male patient incidentally diagnosed to have aortic regurgitation (AR). The patient had a history of a blunt trauma to the thorax two years back but did never have any symptoms. Transthoracic echocardiography showed a moderately dilated left ventricle with normal systolic function and severe AR with normal nondilated aortic root and tri-leaflet aortic valve. To diagnose the etiology of the AR, a transesophageal echocardiogram (TEE) was done, which revealed a perforation in the nonadjacent leaflet (NAL) and confirmed severe AR with two AR jets being clearly visualized, one through the point of incomplete coaptation and other one through the perforated area in the NAL. The patient was treated with aortic valve replacement and was doing well on follow-up.     

Epstein-Barr virus: Biology and disease

Epstein—Barr virus is a human herpes virus which, whilst found as a widespread asymptomatic infection, is also associated with certain tumours of lymphoid and epithelial origin including Burkitt's lymphoma (BL), immunoblastic lymphoma (IBL), Hodgkin's Disease (HD) and nasopharyngeal carcinoma (NPC). A unique characteristic of EBV is its ability to infect and transform primary resting B lymphocytes in vitro into permanently growing lymphoblastoid cell lines (LCLs); this effect is associated with constitutive expression of a limited set of viral genes. Interestingly, the pattern of EBV gene expression observed in LCLs in vitro is also a feature of IBLs, a tumour associated with immunosuppression. The other EBV associated tumours display a more restricted pattern of EBV latent protein expression. B cell lines can be activated in vitro into the virus replicative cycle, where a large number of viral genes associated with EBV DNA replication and virus assembly are synthesised. Whilst EBV can be detected in throat washings from seropositive individuals, the only in vivo situation where full virus replication can be reliably observed is hairy leukoplakia (HL), a benign lesion of lingual epithelium frequently found in AIDS patients. Thus, the relative contribution of lymphoid cells and epithelial cells to latent EBV infection/persistence vs replication in vivo remains controversial. Recent studies suggest that HL represents a focus of EBV replication in the absence of a truly latent infection and this supports the contention that EBV persistence resides in the lymphoid compartment. These aspects together with the role of EBV in oral diseases and the effect of certain EBV genes on the control of epithelial cell growth and differentiation will be discussed.     

Acupuncture for osteoarthritis of the knee

Miller E, Maimon Y, Rosenblatt Y et al. Delayed effect of acupuncture treatment in OA of the knee: a blinded, randomized, controlled trial. Evid Based Complement Altern Med 2011; Article ID 792975. doi:10.1093/ecam/nen080     

The use of a guide catheter extension system as an aid during transradial percutaneous coronary intervention of coronary artery bypass grafts

Aims : Prior coronary artery bypass graft (CABG) surgery is one of the main predictors of failure of transradial PCI. Frequently this is due to difficulty in graft cannulation and/or poor backup support. In addition to Proxis's? embolic protection role, the Proxis?, Heartrail?, and GuideLiner? guide catheter extension devices have all been shown to facilitate coronary intervention by increasing backup support and aiding stent delivery. We describe our institution's experiences using these devices to aid transradial graft intervention. Methods : Between October 2007 and March 2010, the utility and safety of these devices were assessed in consecutive transradial graft intervention procedures. Proxis? cases used for proximal protection alone were excluded. Deep intubation was defined as an intubation depth of ≥2cm. Results : Guide catheter extensions were used in 33 of 41 transradial graft interventions identified. Proxis? was used for proximal protection alone in 3 cases, leaving 30 cases as the study group (Heartrail? n = 18, GuideLiner? n = 3, Proxis? n = 9). In all study cases procedural success with final TIMI‐3 flow was achieved. Guide catheter extensions were used to aid during graft cannulation (n = 11), to improve backup support via deep intubation (n = 26) and as an adjunctive aspiration device (n = 11). Filter‐based distal embolic protection devices were used in 11/21 Heartrail? and GuideLiner? cases. Deep intubation depths ranged from 30 to 138 mm (mean 61 mm) with no complications related to deep intubation seen. Conclusions : The use of guide catheter extension systems facilitated transradial graft intervention via several mechanisms including aid to graft cannulation, increasing backup support, and as an adjunctive aspiration device. © 2011 Wiley Periodicals, Inc.     

Response of mammary tumors to caloric restriction for different time periods during the promotion phase

Rats treated with 7,12‐dimethylbenz[a]anthracene were subjected to 25 % caloric restriction for varying times during the promotion/progression phase of mammary tumorigenesis. Caloric restriction was inhibitory to a statistically significant extent when it was maintained for the entire four‐month study or only during the first or last two months. Restriction for the first month with subsequent ad libitum feeding led to rapid weight gain with concomitant appearance of tumors. These data indicate that caloric restriction can be instituted late in the tumorigenic process with an acute response of tumor growth to caloric intake or body weight.