Transplant data: sources, collection and research considerations, 2004

The process of collecting and analyzing transplant data is complex. Familiarity with how these data are collected is crucial to a thorough understanding of the information. This article focuses on available OPTN-SRTR data and the continuing evolution of data collection mechanisms; how that data collection system is improving the data quality and reducing the data collection burden; how additional ascertainment of outcomes both completes and validates existing data; and caveats that remain for researchers. This year's article focuses further on research considerations related to cohort choice, timing of data submission, and potential biases in follow-up data. Ongoing improvements in data collection timeliness and scope are covered. The impact of extra ascertainment of outcomes, particularly for post-transplant kidney graft failure from Medicare data, are also examined. A section on graft failure reporting among different sources traces the steps by which the SRTR reconciles different data sources in its analyses. It is important that those reading and conducting transplant research understand the origin, structure, and scope of the available data. All of these issues should be carefully considered when choosing cohorts and data sources for analysis.     

Structure function interface with sequential shortening of basal and apical components of the myocardial band

Objective: To mechanically test the intact cardiac structure to determine the sequence of contraction within the myocardial mass to try to explain ejection and suction. Methods: In 24 pigs (30–85 kg), segment shortening at the site of sonomicrometer crystals was continuously recorded. The ECG evaluated rhythm, and Millar pressure transducers measured intraventricular pressure and dP/dt. Results: Study of segment shortening defined a sequence of contraction within the myocardial mass, starting at the free wall of the right ventricle and on the endocardial side of the antero-septal wall of the left. Crystal location defined underlying contractile trajectory; transverse in right ventricle followed by basal posterior left ventricle, and from the endocardial anterior wall to the posterior apical segment and finally to the epicardial side of the anterior wall. Mean shortening fraction averaged 18±3%, with endocardial exceeding epicardial shortening by 5±1%. Epicardial segment crystal displacement followed endocardial shortening by 82±23 ms in the anterior wall, and finished 92±33 ms after endocardial shortening stopped, time frame that matches the interval of fast drop of ventricular pressure and the start of suction. Conclusions: Crystal shortening fraction sequence followed the rope-like myocardial band model to contradict traditional thinking, with two starting points of excitation–contraction, the right anterior free wall of the right ventricle, and the endocardial side of the anterior wall. Active suction may be due to active shortening of the epicardial fibers of the anterior wall, because relaxation was not detected when both mitral and aortic valves were closed during the interval previously termed ‘isovolumetric relaxation’.     

老年冠心病患者踝臂指数和心脏结构与功能的相关分析

目的探讨老年冠心病患者踝臂指数(ABI)和心脏结构与功能的相关性。方法87例老年冠心病患者,按ABI分组,A组ABI≤0.9,B组ABI>0.9,同时测量2组的心脏结构指标:左心房直径(LAD)、左心室舒张期直径(LVDD)、左心室后壁厚度(LVPW)。左室收缩功能指标:左室缩短率(FS)、左室射血分数(EF)。左室舒张功能指标:EF斜率。结果A、B2组比较,年龄、血脂、血糖、肝功能、肾功能、LAD、LVDD、LVPW和EF斜率均无显著性差异。FS和EF均有显著性差异,A组较B组明显降低(P<0.05)。结论ABI与老年冠心病患者的心脏功能有较好的相关性,对其预后的判定有一定的价值。     

阴茎包埋对海绵体内一氧化氮合酶的影响

目的:探讨阴茎包埋对海绵体内一氧化氮合酶(NOS)活性的影响。方法:通过建立大鼠隐匿阴茎模型获得实验标本,分2个月组、4个月组和6个月组进行观测,每组80只大鼠。各阶段中包括包埋组(n=50)、假手术组(n=15)和正常组(n=15)。称量大鼠体重和海绵体重量后,采用化学比色法检测海绵体内NOS活性。结果:各阶段包埋组阴茎海绵体重量、体重及两者的比值与正常组和假手术组比较均无显著性差异(P>0.05);包埋降低大鼠阴茎海绵体组织的NOS活性(2个月组P>0.05,4个月组P<0.05,6个月组P<0.01)。结论:阴茎包埋可影响海绵体内NOS活性,且与包埋时间呈正相关,但对海绵体外观和重量无明显影响。     

Improving Femoral Bone Density Measurements

Femoral bone density measurements are clinically important because of their strong relationship with hip fracture. However, current densitometers have not improved upon femoral densitometry since the introduction of dual-energy X-ray absorptiometry (DXA) systems. Recently, several advances in DXA measurement of the proximal femur have been proposed by various published studies. These advances can be added to existing DXA systems, while maintaining the conventional femoral regions of interest. Both upper neck bone mineral density (BMD) and hip axis length have been reported to be associated with hip fractures. With newer technology that enables a rapid assessment of both hips, bilateral femur measurements are now clinically practical and are of importance in those with T-scores approaching, yet not reaching, diagnostic or therapeutic thresholds. Bilateral femur measurements also reduce precision error compared to a single femur measurement, yielding precision errors less than observed at the spine. With this decrease in precision error, monitoring of bone changes is now possible at the femur with the utility comparable to the spine.     

Influence of elevated pH levels on structural and functional characteristics of the human zona pellucida: Functional morphological aspects

Purpose A total of 86 fresh and salt-stored immature human oocytes derived from postmortem ovarian tissue were used for this study.Methods Oocytes were randomly incubated either in synthetic human tubal fluid medium (untreated zonae) or in a chemically defined medium (treated zonae).Results Sperm binding experiments using hemizona assay conditions exhibited a 10-fold increased binding of sperm to treated compared to untreated oocytes (272.7±43 versus 24.3±15 sperm bound, respectively; P<0.0001). pH recordings during incubation showed elevated pH levels of 8.1 compared to pH 7.2 among treated and untreated zonae, respectively. Ultrastructural examination showed a spongy appearance of the surface of treated zonae, whereas untreated zonae appeared compact with smooth surface.Conclusions The marked increase in sperm binding among treated zonae, together with the ultrastructural findings, suggest that the altered zona surface enhances sperm binding. The physiological maturational process of the zona pellucida might be manipulated in vitro, thus increasing sperm binding to the zona.Presented at the IXth World Congress on In Vitro Fertilization and Alternate Assisted Reproduction, April 3–7, 1995. Vienna, Austria.     

关于新型农村合作医疗的支持结构及均势模式探讨

新型农村合作医疗可持续发展需要有完备的社会支持系统,除了要有来自政府的正式支持,如政府责任、完善的组织管理及合理的政策方案外,其他非正式支持同样对新型农村合作医疗的发展有着至关重要的影响。通过研究新型农村合作医疗的社会支持系统结构,探讨社会因素对新型农村合作医疗的双向作用,提出新型农村合作医疗发展的社会支持模式,为提高新型农村合作医疗社会支持程度提供科学依据。     

Metabolic and hormonal blood flow modeling in patients with coronary heart disease: In vitro and clinical study

The blood flow pattern investigations are of great importance in coronary blood flow destabilization pathogenesis understanding, and consequently in acute coronary event (ACE) risk stratification in patients with coronary heart disease. The aim of the study was to research the principal hormonal and metabolic blood flow regulative aspects and its structure in patients with ischemic heart disease and the contribution to cumulative ACE risk.A total of 182 patients with stable angina pectoris were included in the prospective study (2000–2006). Complex clinical examination, biochemical tests and blood tests were performed. Whole-blood (WB) viscosity, erythrocyte aggregation and deformation ability, WB suspension stability, and initial erythrocytes disaggregation parameter were studied. Dynamic characteristics of blood flow were obtained in the experiment.Received results allow marking the principle components of blood flow pattern with proven high prognostic value of ACE in patients with ischemic heart disease. ACE risk stratification program was developed.