Development and Initial Testing of a Permanently Implantable Centrifugal Pump

Abstract: To be able to salvage heart failure patients, the need for an economical permanent ventricular assist device is increasing. To meet this increasing demand, a miniaturized centrifugal blood pump has been developed as a permanently implantable device. The Gyro permanently implantable model (PI-601) incorporates a sealless design with a blood stagnation free structure. The pump impeller is magnetically coupled to the driver magnet in a sealless manner. This pump is atraumatic and antithrombogenic and incorporates a double pivot bearing system. A miniaturized actuator was utilized in this system in collaboration with the University of Vienna. The priming volume of this pump is 20 ml. The overall size of the pump actuator package is 53 mm in height and 65 mm in diameter, 145 ml of displacement volume, and 305 g in weight. Testing to date has included in vitro hydraulic performance and hemolysis. This pump can provide 5 L/min against a 110 mm Hg total pressure head at 2,000 rpm and 8 Limin against 150 mm Hg at 2,500 rpm. The normalized index of hemo-lysis (NIH) value of this pump was 0.0028 g/100 L at 5 Limin against 100 mm Hg. A preliminary anatomical study revealed the possibility of the implantability of 2 such systems in biventricular bypass at a preperitoneal location. This system is feasible for use as a permanently implantable biventricular assist device.     

Experimental Assessment of Right Ventricular Function in Normal Pigs with a Left Ventricular Assist Device

Abstract: Right ventricular (RV) failure during the use of a left ventricular assist device (LVAD) is the leading cause of death in circulatory support patients. Previous work, both experimentally and clinically, has shown the difficulties in predicting the behavior of the right ventricle at the start of LVAD. An experimental study has been designed to evaluate RV functional changes during LVAD and its relation to preload changes. The model used adult mongrel pigs (n = 10). Right ventricular functional parameters were measured with a thermodilution RV ejection fraction catheter. The left ventricle was supported by a Nippon Zeon blood pump. Two groups were studied, the first one was the LVAD–off group (n = 5) and the other was the LVAD–on group (n = 5) which was supported by LVAD at maximum flow. Change of cardiac output, mean pulmonary artery pressure (PAP), RV stroke work, and RV ejection fraction in both groups were not significantly different. However, the relationship between right ventricular end–diastolic pressure (RV–EDP) and right ventricular stroke volume (RVSV) was significantly changed at a high level of RV–EDP. When RV–EDP was over 6. 5 mm Hg in the LVAD–off group, RVSV decreased to 52. 3 ± 11. 5 ml while in the LVAD–on group, RVSV increased to 97. 2 ± 22. 0 ml. The change in PAP in the LVAD–on group was lower than in the LVAD–off group. We conclude that, at the volume overload state, LVAD can reduce the afterload of the right ventricle and maintain Frank–Starling's effect, thus having a beneficial effect on right ventricular performance.     

医疗器械产品召回制度探讨与典型案例分析

着重介绍了国内外医疗器械产品召回制度现状,并以强生血糖仪、佳腾除颤器两起召回事件为案例,阐明整个召回事件处理的过程,旨在为我国建立和完善医疗器械产品召回制度提供借鉴。     

亮氨酸脑啡肽的电子结构及构效关系研究

对亮氨酸脑啡肽进行了量子化学(INDO)计算,研究其电子结构特征,讨论其活性部位、作用机理及构效关系。同吗啡和R31833进行了活性部位的电子结构与空间结构比较,推断它们的活性药效结构具有共同特点,与阿片受体相互作用时作用方式相同,作用部位有对应关系,因而具有相同的药理性质。     

Controlled release of sugar and toxicant from a novel device for controlling pest insects

A novel biodegradable device, designed for long-lasting residual effectiveness of feeding stimulant (sugar) and insecticide (dimethoate) against apple maggot flies and other insects, was formulated. The device is an 8-cm diameter fruit-mimicking sphere, consisting of 42–50% sugar entrapped in a mixture of gelatinized corn flour and wheat flour in the presence of glycerin, and coated with a layer of latex paint containing dimethoate and sugar. We found that the outer layer of paint prevents cracking of the sphere upon drying and creates a barrier to control the release of both sugar and dimethoate. Releases of each ingredient were screened first by chemical analysis and then by bioassays in the laboratory and in field cages against apple maggot flies. Chemical analysis demonstrated strong potential for controlled release of water-soluble feeding stimulant and water-insoluble insecticide measured as a function of the amount of rainfall and duration of exposure time. Field results showed greater than 70% insecticidal activity after 11 weeks of sphere exposure in an orchard. This device has the potential to be used for a variety of insect-control applications through manipulating its shape, color and texture into forms known to be attractive to target insects, and by employing various toxicants designed to be effective against such insects.     

表面改性在介入器械上的应用

论述赋予介入器械的材料表面润滑性、抗菌性、抗凝血性及抗组织增生等性能的各种表面改性技术的现状，讨论这些技术的一些应用的实例，提出需要进一步研究的问题。     

脑出血患者血肿周围组织病理及超微结构变化的动态观察

目的观察脑出血患者血肿周围组织普通病理及超微结构的动态变化。方法对30例脑出血患者采取非功能区人颅直视手术，清除血肿前于血肿旁约1cm处取少许脑组织作为实验组，按发病到手术的时间分为6h以内组6例，6～12h组7例，12～24h组5例，24～48h组3例，48～72h组3例，3～4d组3例，5d组2例，8d组1例。从12h以内组中的7例患者于手术入颅路径上远离血肿处取少许脑组织作为对照组。应用光镜_硐J电镜观察脑组织普通病理及超微结构的动态变化。结果对照组脑组织形态和结构基本正常。实验组6h以内脑组织有轻微损伤。6h以后脑组织损伤逐渐加重。24～48h损伤达高峰，光镜显示脑细胞和纤维水肿明显，细胞形态不完整，核固缩，炎性细胞侵润明显；电镜显示神经元细胞核变空染色质聚集，线粒体肿胀，嵴变短或消失，核糖体减少，次级溶酶体增加，细胞变空，细胞膜不完整，胶质细胞核固缩。72h以后损伤逐渐好转，5d时损伤与6～12h组相似，8d时基本好转，与6h以内组基本接近。结论脑出血后血肿周围脑组织继发性损伤早期就有病理改变，损伤高峰在24～72h，与一般脑出血临床神经功能损害的变化规律基本一致。     

CTI和3G技术在120急救指挥中心的应用

介绍了120急救指挥中心的结构、计算机电话一体化和卫星定位系统、地理信息系统以及无线通讯系统的功能，分析了CTI和3G技术在120急救指挥中心的实际应用和取得的成效。     

Use of a Paracorporeal Pneumatic Ventricular Assist Device for Postoperative Cardiogenic Shock in Two Children with Complex Cardiac Lesions

Pneumatic ventricular assist device (VAD) was utilized for cardiogenic shock after intracardiac operation in two children with complex cardiac anomalies based with single ventricle. In the first case (a 10-year-old), after a modified Fontan operation, VAD was placed between the functional left atrium and ascending aorta, serving as a "artificial single ventricle" with neither pumping chamber nor artificial support in the right side of the heart. The systemic circulation was maintained by keeping relatively high central venous pressure. In another child (a 3-year-old) who underwent repair of incompetent atrioventricular valve leaving intracardiac lesions, VAD was placed between the common atrium and ascending aorta, serving as a pump for both pulmonary and systemic circulation with regulation of pulmonary blood flow through an aortopulmonary Gore-Tex shunt. The circulatory assist with VAD was utilized for 5 and 6 days, respectively. Although weaning from the device was not feasible in both patients because of the pulmonary dysfunction, these experience showed the possible use of VAD for cardiogenic shock after surgery in patients with complex cardiac anomalies.     

“E（疫）”时代背景下大学生心理危机干预体系构建的思考

本文探讨信息时代背景下,在校大学生高发心理危机的原因,并倡导高校教学管理人员充分利用当下信息技术成果对在校大学生进行心理评估和常态化心理教育,并依托当前高校信息化建设平台收集相关信息,构建易感大学生的心理危机预警及干预机制,以期将端口前移,更好地保障在校大学生的心理健康。