克山病与心肌线粒体病

克山病是我国一种严重的地方性心肌病. 1984 年政府曾组织对克山病高发地区之一—云南省楚雄地区进行综合性科学考察. 考察队由流行病学、生态环境、临床防治、病理学、生物化学等方面的专家组成, 历时3年(1984~1986年). 通过考察, 病理学、生物化学、生物物理、临床治疗等方面的研究结果均显示克山病患者心肌线粒体的病变是一个重要特征. 该病的具体表现为心肌线粒体代偿增生、数目增多、嵴膜破坏、氧化磷酸化酶系(包括琥珀酸脱氢酶、细胞色素c氧化酶、琥珀酸氧化酶、H^＋-ATP酶等)活性明显下降, Ca²⁺含量增高、心磷脂和辅酶Q含量偏低, 从而提出: “克山病是一种心肌线粒体病”的观点. 在此之前, 对“心肌线粒体病”仅有极少的个例研究报道. 通过楚雄考察, 对众多克山病病例进行大量、多方面的测试与分析, 获得十分珍贵的研究资料. “克山病是一种心肌线粒体病”的提出, 是楚雄考察的重要成果之一, 它不仅是对克山病的发病机理的深入认识, 而且对“心肌线粒体病”的研究都是很有意义的. 与其它“心肌线粒体病”不同, 克山病不属于遗传性疾病, 而与营养不足(特别是缺乏微量元素硒)密切相关. 克山病都发生在缺硒地带, 而补硒对克山病有明显的预防作用. 随着我国人民生活水平的提高, 克山病发病率逐年下降, 目前已降至极低的水平. 近年来国际上对非克山病的心肌线粒体病的研究日益增多. 本文结合这方面的研究进展对“克山病是一种心肌线粒体病”作一简短评述.     

克山病病区粮喂养大鼠后心肌细胞自由钙浓度变化与硒的作用

为了解克山病的发病机理,本文研究了低硒对心肌细胞钙转运的影响。用克山病病区粮喂养的大白鼠与用非病区粮喂养的大白鼠相比,心肌细胞胞浆自由钙的浓度高,心肌细胞膜流动性及Na~+,K~+-ATP酶活性也高,在病区粮中添加适量的硒,上述指标与用非病区粮喂养的大白鼠的差距缩小,说明低硒是引起心肌细胞钙转运失常从而使细胞浆自由钙浓度升高的重要因素但不是唯一的因素,文中讨论了细胞浆自由钙浓度与细胞膜流动性、Na~+,K~+-ATP酶活性及心肌线粒体功能的关系,以及低硒对它们的影响。     

克山病病区粮低Se对大白鼠心肌线粒体Ca转运影响的研究

以低Ｓｅ克山病病区粮喂养大白鼠为动物模型,在细胞及亚细胞水平上进行了低Ｓｅ与Ｃａ转运关系的研究,同时测定了线粒体的能量转换功能。结果显示,低Ｓｅ病区粮组动物心肌线粒体Ｃａ转运呈现明显异常,但线粒体能量转换功能尚未发生明显改变。提示线粒体Ｃａ转运功能损伤先于线粒体能量转换功能损伤之前发生。心肌线粒体Ｃａ转运功能可作为更灵敏的指标用于克山病发病机理的研究。上述结果进一步表明克山病是一种“心肌线粒体病”。     

慢型克山病心功能代偿期超氧化物歧化酶活性的初步探讨

超氧化物歧化酶(SOD)是体内超氧化物阴离子自由基(·O_2~-)的清除剂。近年来,国内外研究发现,它在炎症、肿瘤、老年病等疾病的发生发展中都起着重要作用。亚急型克山病和慢型克山病(慢克)急性发作住院的患者红细胞SOD活性降低已有报告,现将慢克心功能代偿期患者的SOD活性报告如下     

克山病心肌线粒体氧化损伤的实验研究

用克山病区粮喂养豚鼠证明其红细胞、肝等组织及其线粒体、上清中的硒及谷胱甘肽过氧化物酶活性明显降低,心肌线粒体脂质氢过氧化物、荧光色脂等增加、同时膜脂组成异常,内膜界面脂的心磷脂(CL)减少,细胞色素C氧化酶(CCO)活性降低;园二色性(CD)异常,近208nm及222nm区的峰值降低,病区粮加喂青菜的动物,随其线粒体硒及CL水平的增加。CCO活性和CD谱均明显恢复;通过外源性磷脂与纯化CCO的重组复性实验,只有CL可使病区粮组酶活性完全达到正常对照水平。表明心肌线粒体膜结合酶CCO活性的降低是CL含量降低引起酶的二级结构(构象)改变的结果。     

落花生不同器官对硒元素吸收和累积动态的研究

通过盆栽试验研究了落花生(Arachis hypogaea L.)对硒元素的生物富集作用。结果表明:随着生长发育期的推进,落花生对硒的生物累积作用呈动态变化,表现在植株体内硒的含量、硒元素累积进程及其贮量上。硒在植株内的累积以下针期为转折点,呈前轻后重之势,全株中55％的硒是结荚后累积的,下针期前硒以叶片为累积贮存中心,其后以荚果为中心,硒在植株内趋向于分布在植株生长旺盛的器官。成熟收获后,植株不同器官的贮量以果仁>叶>果壳>茎>根,含量分布为果仁>根>果壳>茎>叶。     

新城疫病毒单克隆抗体的特性及应用

建立了8个分泌抗新城疫病毒(NDV)特异性单克隆抗体(McAb)的杂交瘤细胞株,根据它们的免疫生物学特性可以分为三种类型:(1)具有FA和ELISA特性(FN1、FN4、FN29、FN30、FN35、FNl22);(2)具有FA、ELISA和HI特性(FN7);(3)具有ELISA、HI特性和中和能力(FN106),根据FN30和FN106的ELISA试验,可将11个NDV毒株分为二种不同的抗原群,应用FN4-FITC,FN7-FITC和FN29-HRP试剂,对人工感染NDV和野外送检病例检测结果表明,单抗试剂的DFA阳性率(92.3％)高于病毒分离阳性率(87.2％),两种方法的符合率89.7％,这些单抗试剂用于临床诊断敏感性和特异性高,且方法快速、简便。     

海洋生物技术在海水养殖动植物品种培育和病害防治中的应用

海水养殖是我国沿海地区发展经济的重要支柱产业。目前影响我国海水养殖业持续、稳定、健康发展的主要制约因素是苗种和病害问题。本文就海洋生物技术在海水养殖物植物品种培育和病害防治中的应用及有关问题进行了探讨,分别就应用海洋生物技术在群体和个体水平、细胞和染色体水平以及基因和分子水平培育新品种的工作,包括ＳＰＦ和ＳＰＲ苗种的培育、性别控制和杂交育种、多倍体育种、雌核发育、藻类细胞工程育种、转基因技术等进行了讨论。在重要水产养殖疾病病原的快速诊断和检测技术方面,重卢、讨论了核酸探针技术,ＰＣＲ技术和单克隆抗体技术。海洋生物技术在水产养殖疾病防治中的应用,重点讨论了疫苗和免疫促进剂的开发以及基因工程疫苗。本文还对我国海洋生物技术的发展战略及有关问题进行了探讨。     

磁水处理后蕃茄过氧化物酶活性与抗病力的关系

实验结果表明:蕃茄经磁水处理后,在其营养生长期间,抗病力增强,并与过氧化物酶活性有一定相关性。并发现。于苗期接种TMV后,病害级別低的植株酶活性低,与对照组相比较,具较强抗病力的处理组,其酶活性变化较小。可以认为,磁水可能通过活化调节基因,控制过氧化物酶活性,从而能提高蕃茄的抗病力。     

HEART DISEASE AND SOCIAL INEQUALITY: ETHICAL ISSUES IN THE AETIOLOGY, PREVENTION AND TREATMENT OF HEART DISEASE

Heart disease is a complex condition that is a leading cause of death worldwide. It is often seen as a disease of affluence, yet is strongly associated with a gradient in socio-economic status. Its highly complex causality means that many different facets of social and economic life are implicated in its aetiology, including factors such as workplace hierarchy and agricultural policy, together with other well-known factors such as what passes for individual 'lifestyle'. The very untangling of causes for heart disease thus inevitably raises social, moral and political issues. These include the proper role of the individual and of larger social forces in its aetiology, prevention and treatment. The construction of risk factors for heart disease likewise is enmeshed with questions of distributive justice in the responsible targeting of those at risk for heart disease, a debate which has received much overt attention in the medical literature, but less attention within the ethical literature. Strategies for addressing a condition of such complex causality can be highly diverse, from pharmaceutical to social interventions, and value issues attach to the choice and presentation of such strategies. For example, prevention strategies may raise complex issues of responsibility and of judgements of what it is to 'live well'. Further ethical debate on this highly political disease would be welcome.     

水稻白叶枯病菌系和品种抗性鉴定的病情指标评价

从全国各病区筛选的19个代表菌株,在三套（中国、日本和IRRI）16个鉴别品种上进行测试,获得4个病情指标,即病班长度、病级、日增速率和日增百分率,采用不同的病情指标作方差分析,所得结果不完全一致;对4个病情指标进行相关及回归分析,结果表明,病情指标之间是存在显著的线性相关,且日增百分率为日增速率与病叶长度之商,这种相关性在主成分分析中也得到了证实,通过聚类分析发现,病斑长度不能与其它3个指标归为一类,最后对水稻白叶枯病菌系及品种抗性鉴定中采用的4种病情指标的优劣进行了讨论．     

ANTHER-SMUT DISEASE IN SILENE DIOICA: VARIATION IN SUSCEPTIBILITY AMONG GENOTYPES AND POPULATIONS,AND PATTERNS OF DISEASE WITHIN POPULATIONS

In an archipelago in northern Sweden, populations of the perennial, dioecious, and insect-pollinated herb Silene dioica are commonly infected by the sterilising anther-smut fungus Microbotryum violaceum. The results from transplantation and inoculation experiments in this study show that variation between populations in the incidence of disease may partly be due to variation in resistance among populations. In the transplantation experiment in which plants were naturally exposed to the fungus, disease levels varied greatly among transplants from three healthy populations when transplanted to three diseased populations in the archipelago. Clear genotypic differences in susceptibility among 25 replicated genotypes of the host plants were found when inoculated manually with two different isolates. Susceptibility varied between 0-90%, but the two isolates used did not differ in inoculation success. The results also suggest a geographical structuring in resistance of the host and virulence of the fungus. First, disease levels among experimental plants from two of the disease-free populations of S. dioica (originating from inner and outer archipelago, respectively), were high when transplanted to a diseased population nearby, but low when transplanted far away. Second, regardless of origin, plants from all healthy populations became diseased in the diseased experimental populations located in the middle part of the archipelago. Due to isostatic land upheaval in the studied archipelago, there is a vertical age-axis within islands such that the highest point on an island is the oldest. Since this may affect the demography of the host, disease spread, and the dynamics of disease, spatial patterns in adult and seedling densities, and disease and spore deposition along the age-axis were studied within three diseased populations. A low incidence of disease was found in the young, low and old, high parts of the populations and a high incidence in the vertical, middle parts of the populations. The higher disease incidence in the middle part compared with the lower part of the population may reflect less disturbance and an increased probability of disease with age.