Bactericidal Low Density Polyethylene (LDPE) urinary catheters: Microbiological characterization and effectiveness

This study investigated the antimicrobial efficacy of Low Density Polyethylene (LDPE) catheters containing triclosan at 0.10 wt.%, 0.50 wt.%, 1.00 wt.% and 1.50 wt.%. The catheters were characterized with the Minimum Inhibitory Concentration (MIC) and Agar Diffusion Tests. They were evaluated in terms of incrustation, biofilm formation and the efficiency of inhibition of bacterial growth after thirty days of lab tests with artificial urine. This research demonstrated the effectiveness of triclosan for inhibiting the growth of microorganisms when incorporated into long-term catheters. The antimicrobial efficiency and genotoxicity results demonstrate that 0.5 wt.% triclosan is the optimal concentration. The genotoxicity test results indicate that triclosan did not result in any significant alterations in the cellular DNA compared to the catheter without triclosan.     

Use of an alteplase algorithm for the management of hemodialysis catheter dysfunction

Hemodialysis (HD) catheter dysfunction compromises HD adequacy and increases the cost of patient care. Repeated administration of alteplase in HD catheters typically produces only short-term benefits. The purpose of this study was to design, implement, and evaluate the efficacy of an experimental alteplase algorithm to manage HD catheter dysfunction. This was a two-part prospective nonrandomized study. Baseline data of alteplase use and catheter exchange were collected during part 1 of the study. Part 2 consisted of the alteplase algorithm implementation and repeat collection of catheter data. Rates of alteplase use and catheter exchange per 1000 catheter-days were the primary and secondary outcomes of the study. One hundred and seventy-two catheters in 131 patients were followed prospectively during the course of the study. The adjusted relative rate (RR) of alteplase use showed no significant difference between both parts of the study, adjusted RR: 1.10, 95% confidence interval (CI) (0.73-1.65). Similarly, catheter exchange rates were not significantly different over the duration of the study (1.12 vs. 1.03 per 1000 catheter-days). However, waiting time for catheter exchange increased from 20.36 ± 14 days in part 1 to 38.42 ± 28 days in part 2 (P < 0.05). The alteplase algorithm did not significantly reduce alteplase use. This may be partially explained by repeated use of alteplase in part 2, due to longer waiting times for catheter exchange procedures.     

系留气球拉索汇流装置结构设计

拉索汇流装置是系留气球的关重件,其主要功能是在气球升空及滞空时将系留缆绳的集中载荷均匀分散传递至球上拉索,它直接影响系留气球的高空飞行安全。文中根据浮空器产品设计规范,结合拉索汇流装置的使用技术要求,对装置的结构形式和材料本体等进行了重点设计;然后通过计算机软件建立有限元模型,对装置的整体强度特性进行了仿真计算和理论分析;最后在实验室内对仿真分析结果进行试验验证。装置的强度试验验证结果显示,该装置完全满足强度设计要求。     

我国GCOS高空站1600g气球长度与爆破直径的确定

根据已有规格的气球表面积上的单位质量与长度的关系确定了气球长度下限;应用理想气体绝热方程,从理论上推算出1600g气球的爆破直径,并在实际应用中加以验证,同时结合国外的相关标准和我国行业标准,对1600g气象气球长度及爆破直径的确定进行探讨,制定出1600g气球标准的长度和爆破直径≯     

球囊导管的制备及连接方法探讨

以尼龙12为双腔管的主要材料、聚对苯二甲酸乙二酯为球囊的主要材料,制备了球囊导管。通过实验对胶粘剂连接、热熔焊接、超声波焊接和激光焊接技术作了初步的探讨,试图寻求一种良好的球囊导管的连接方法。     

电感耦合等离子体发射光谱法测试气球中17种元素

建立了全谱直读电感耦合等离子体发射光谱法（ICP-AES）测定气球中17种可溶性元素的分析方法,确认了元素分析谱线和试验条件。各元素报出限在0．02～2mg／kg,加标回收率为88．7％～103．2％之间,相对标准偏差RSD均小于3．9％,适于玩具气球的日常检验。17种元素在气球中均有检出,部分产品中锌的质量分数接近欧盟2009／48／EC号指令的限量要求,铅的质量分数超过欧盟2009／48／EC号指令的限量要求。由于欧盟2009／48／EC号指令规定的17种元素含量过高,则可能影响人体健康。     

系留气球拉力传感器数字滤波算法研究

拉力传感器是系留气球上测量缆绳张力的重要部件,处于系留气球复杂的干扰环境中测量准确度一直很低。本文提出了一种数字滤波算法,基于对拉力传感器信号的分析和滤波验证,证明此算法有很好的滤波效果同时保持了对突变信号的跟随性。     

环锭细纱机高速纺纱断头问题探讨

研究细纱机变速段瞬时断头问题,定性分析气圈张力振动波形的主要谐波,气圈本身圆偏振波、导纱钩处张力波及共振波的形成和性质;说明张力波动的重要因素及钢领板运动转向时出现突发张力的原因。指出：钢丝圈运动是按钢领板升降规律变化的变速运动,是导纱钩处张力波动的主要谐波,是张力波动的重要因素;细纱大、小纱断头的原因是存在超大的突发性张力峰值,可能为共振。     

In vitro stability and compatibility of tenecteplase in central venous access devices

Central venous access devices (CVADs) aid in the delivery of nutritional support, infusion therapy, and hemodialysis. Maintaining continuous flow through these devices is challenging, because they are susceptible to complications such as thrombi occlusion. Therefore, CVADs may require treatment with anticoagulant or thrombolytic agents. Using these agents as locking solutions has been widely investigated; however, few publications have described the compatibility of the therapeutic with the CVAD itself. The objective of this investigation was to evaluate the in vitro stability and compatibility of a thrombolytic biologic agent, tenecteplase, with various CVAD materials. Tenecteplase was reconstituted to 1 mg/mL with either sterile water for injection or bacteriostatic water for injection (0.9% benzyl alcohol) then incubated in glass vials, polysulfone/silicone vascular access ports, and polyurethane or silicone catheters for up to 96 hours. Biochemical assays including protein monomer, protein one-chain, and in vitro bioactivity were used to assess tenecteplase's compatibility with the investigated diluents and materials every 24 hours. Antimicrobial testing was also performed for up to 28 days on bacteriostatic water for injection-reconstituted samples only. Our results showed tenecteplase to be compatible with both types of diluents (in glass vials) and catheters for up to 72 hours. Furthermore, tenecteplase was compatible with the polysulfone/silicone vascular access ports for up to 24 hours. Finally, bacteriostatic water for injection-reconstituted tenecteplase effectively met USP criteria for the inhibition of growth of micro-organisms. This study serves as an example of a best practice to evaluate the in vitro stability and compatibility of a biologic agent with CVAD materials.     

Carotid-jugular arteriovenous fistula: a case report of an iatrogenic complication following internal jugular vein catheterization for hemodialysis access

We report a case of diabetic end-stage renal disease patient who presented with a right common carotid artery jugular arteriovenous fistula as a complication of the insertion of a polyurethane double-lumen hemodialysis catheter into the right internal jugular vein .On physical examination of the neck, a pulsating mass with a palpable thrill and a bruit was noted in the right subclavicular region. The diagnosis was confirmed by color doppler ultrasonography of the neck and carotid angiography. The review of the literature suggests the occurrence of this complication as rather rare. The fistula was successfully repaired surgically. It is emphasized that while securing the access, a thorough physical examination with a special emphasis on seeking any neck swellings, thrill, and bruit along with routine use of vascular doppler for securing dialysis access is recommended.