A randomized prospective comparison of chemotherapy to total body irradiation as initial treatment for the indolent lymphoproliferative diseases

One hundred eight consecutive patients with indolent lymphoproliferative diseases were stratified into chronic lymphocytic leukemia (CLL), stage III and IV well-differentiated lymphocytic lymphoma (WDLL), and stage III and IV follicular lymphoma (FL). Within each stratum, patients were prospectively and randomly assigned to receive chemotherapy with chlorambucil and prednisone (CP) or fractionated total body irradiation (TBI). Morbidity from both regimens was negligible. Complete response (CR) was defined as the resolution of organ enlargement and the return of blood count to normal. The CR rate for the entire CP group (n = 54) was 59% and that for the TBI group (n = 54), 52%; median survivals were 53 and 57 months respectively. In the 41 patients with CLL the CR rate for CP (n = 17) was 47% and that for TBI (n = 24), 50%; the median survival for CP was 48 months, and for TBI it was 51 months. In the 21 patients with WDLL the CR rate for CP (n = 15) was 53% and that for TBI (n = 6), 67%; the median survival for CP was 42 months and has not yet been reached for TBI. For the 46 patients with FL the CR rate for CP (n = 22) was 72% and that for TBI (n = 24), 50%; the median survival was 55 months, and for TBI it was 56 months. None of the differences in CR or survival are statistically significant (P greater than .05). In these indolent lymphoproliferative diseases, CP and TBI are equally effective forms of initial treatment irrespective of the end point being defined as CR or survival.     

Linear quadratic optimal model-following control of a helicopter in hover

Presented are results of a study of the application of linear quadratic optimal model-following control applied to a Bell 205 helicopter in hover. The primary objective of good in-flight stability robustness and performance was accomplished via singular value analysis using perturbed systems. Nominal aircraft models were compared with experimental data and discrepancies quantified in a robustness criterion. Current military handling quality requirements were specified as a target model to be followed. The linear quadratic optimal control and command feedforward was found suitable for these requirements. Design analyses enabled consideration of the tuning process, where effects of variations in selected tuning parameters demonstrated their sensitivity to the design.     

Metabolic network failures in Alzheimer's disease: A biochemical road map

Introduction

The Alzheimer's Disease Research Summits of 2012 and 2015 incorporated experts from academia, industry, and nonprofit organizations to develop new research directions to transform our understanding of Alzheimer's disease (AD) and propel the development of critically needed therapies. In response to their recommendations, big data at multiple levels are being generated and integrated to study network failures in disease. We used metabolomics as a global biochemical approach to identify peripheral metabolic changes in AD patients and correlate them to cerebrospinal fluid pathology markers, imaging features, and cognitive performance.

青年人群腰椎骨密度及标准差对骨质疏松检出率的影响：多中心、大样本分析

背景: 不同地区骨峰值和标准差不同，对骨质疏松诊断率有较大影响。探讨建立一完整数据库为中国人骨质疏松诊断准确性提供依据。 目的：探讨青年人腰椎骨密度和标准差正常参考值影响骨质疏松症检出率的程度。 设计、时间及地点：调查分析，于1997-01/1999-12分别在北京、上海、广州、南京、嘉兴和成都市完成。 对象：采用前瞻性及回顾性方法对全国6个中心骨密度参考数据库中11 418人进行调查统计分析；男3 666人，女7 752人；年龄20岁~90岁；分别来自北京(2 385人)、广州(1 178人)、上海(1 404人)、南京(2 938人)、成都(1 425人)、嘉兴(2 088人),受试者来源于社区调查、健康体检和健康志愿者。 方法：用GE-Lunar公司的DXA仪测量骨密度，调查全国6个中心11 418人L2~L4腰椎后前位和髋部骨密度，建立了骨密度参考数据库。6个中心的仪器内部精度0.3%~0.7%，仪器间的精度1.1%。 主要观察指标：①6个中心不同年龄组腰椎骨密度分布。②青年人群骨密度及其标准差值对骨质疏松症检出率的影响。 结果：中国汉族女性以腰椎进行骨质疏松症诊断的青年人群的骨密度和标准差值，6个中心，最大差值分别为0.098 g/cm2和0.027 g/cm2。用6个中心及总体各自的青年人平均骨密度和标准差值为参考标准，对同一人群计算T-score和获得的骨质疏松症检出率不相同；发现青年人平均骨密度每变化0.01 g/cm2，则骨质疏松症检出率变化1.6%(呈正相关)，其标准差值每变化 0.01 g/cm2，则骨质疏松症检出率变化4%(呈负相关)。 结论：青年人平均骨密度和标准差值不同引起骨质疏松症检出率也不相同。为了让不同中心的骨质疏松症检出率有可比性,建议同一个类型的骨密度仪,同一个种族,同一个地区用一个设计较完善大样本的参考数据库,以其青年人正常参考值计算T-score。     

从兔股骨头中提取总RNA的方法特点

目的:建立一种高效、快速的骨组织总RNA提取方法。方法:实验于2005-01/2006-01在昆明医学院实验动物中心和中国科学院昆明动物研究所中科院细胞与分子进化重点实验室完成。取健康新西兰大白兔1只,截取其股骨头,迅速置于液氮罐中保存,于研钵中研磨,使骨组织始终保存于液氮中,继续研磨,如此重复3次,然后利用Trizol使骨细胞结构迅速破坏,将粉末转入离心管,室温静置5min。随后加入氯仿等有机溶剂处理、离心,使RNA与细胞DNA、蛋白质及其他成分分离从而得到总RNA。最后鉴定RNA的质量、纯度及产率,取2μL提取出的RNA在体积分数为0.008的甲醛变性琼脂糖凝胶上进行电泳,主要观察RNA的28S、18S及5S三个条带是否清晰,有无降解和DNA污染。以99μLDEPC水稀释1μLRNA样品,紫外分光光度计测量其吸光度(A)值,A260/A280之比值表示RNA的纯度,同时根据吸光度值计算其质量浓度。结果:①对提取的兔股骨头RNA进行琼脂糖凝胶电泳,可显示清晰的28S、18S两个条带,5S条带亦可见,表明了RNA是完整的。②用紫外分光光度法测定兔股骨头中提取出的RNAA260/A280,结果表明由本法提取的RNA纯度高,无DNA和蛋白质的污染。③经紫外分光光度计吸收定量,每毫克兔股骨头组织能提取1.0～1.2μg的总RNA。结论:本法提取骨组织总RNA方便、快捷,质量高,可用于骨组织的分子生物学研究。     

缺血预处理程序中心肌环磷酸腺苷含量及环磷酸腺苷依赖蛋白激酶活性的变化

目的:制备大鼠在体缺血再灌注模型,观察缺血预处理程序中心肌环磷酸腺苷含量及环磷酸腺苷依赖蛋白激酶活性的变化。方法:实验于2005-03/2006-10在解放军沈阳军区总医院医学实验动物中心和全军心血管研究所实验室完成。实验分组:选用健康雌性SD大鼠36只,根据预适应程序分为第1,2,3次缺血,第1,2,3次再灌注,每一时间点6只大鼠。实验过程:用手术套管法造成左冠状动脉主干缺血及再灌注。所有实验动物在实验程序结束后,取出心脏迅速置液氮保存备用。实验评估:用放射免疫法测环磷酸腺苷水平,生化法测环磷酸腺苷依赖蛋白激酶活性变化。结果:36只大鼠均进入结果分析。①环磷酸腺苷含量:第1次再灌注组低于第1次缺血组[(0.325±0.015),(0.395±0.024)pmol/g,t=6.06,P<0.001],第2次再灌注组低于第2次缺血组[(0.523±0.017),(0.708±0.067)pmol/g,t=6.56,P<0.001],第3次再灌注组低于第3次缺血组[(0.567±0.031),(0.712±0.038)pmol/g,t=7.24,P<0.001]。②环磷酸腺苷依赖蛋白激酶活性:第1次再灌注组低于第1次缺血组[(10.115±1.000),(16.351±0.849)pkat/g,t=11.12,P<0.001],第2次再灌注组低于第2次缺血组[(11.877±2.213),(14.869±0.619)pkat/g,t=3.31,P<0.01],第3次再灌注组低于第3次缺血组[(11.745±0.987),(14.766±0.329)pkat/g,t=7.09,P<0.001]。③缺血预处理程序中心肌环磷酸腺苷含量及环磷酸腺苷依赖蛋白激酶活性随缺血及再灌注呈周期性波动。在5min缺血预处理时表现为明显增高,而在间隔的再灌注程序中恰呈相反改变,有明显下降的趋势。结论:环磷酸腺苷及环磷酸腺苷依赖蛋白激酶的周期性波动变化可能是激发心肌缺血预处理的机制之一,环磷酸腺苷可能在预处理保护作用中起一些作用。