Clear relationship between ETF/ETFDH genotype and phenotype in patients with multiple acyl-CoA dehydrogenation deficiency

Mutations in electron transfer flavoprotein (ETF) and its dehydrogenase (ETFDH) are the molecular basis of multiple acyl-CoA dehydrogenation deficiency (MADD), an autosomal recessively inherited and clinically heterogeneous disease that has been divided into three clinical forms: a neonatal-onset form with congenital anomalies (type I), a neonatal-onset form without congenital anomalies (type II), and a late-onset form (type III). To examine whether these different clinical forms could be explained by different ETF/ETFDH mutations that result in different levels of residual ETF/ETFDH enzyme activity, we have investigated the molecular genetic basis for disease development in nine patients representing the phenotypic spectrum of MADD. We report the genomic structures of the ETFA, ETFB, and ETFDH genes and the identification and characterization of seven novel and three previously reported disease-causing mutations. Our molecular genetic investigations of these nine patients are consistent with three clinical forms of MADD showing a clear relationship between the nature of the mutations and the severity of disease. Interestingly, our data suggest that homozygosity for two null mutations causes fetal development of congenital anomalies resulting in a type I disease phenotype. Even minute amounts of residual ETF/ETFDH activity seem to be sufficient to prevent embryonic development of congenital anomalies giving rise to type II disease. Overexpression studies of an ETFB-D128N missense mutation identified in a patient with type III disease showed that the residual activity of the mutant enzyme could be rescued up to 59% of that of wild-type activity when ETFB-D128N-transformed E. coli cells were grown at low temperature. This indicates that the effect of the ETF/ETFDH genotype in patients with milder forms of MADD, in whom residual enzyme activity allows modulation of the enzymatic phenotype, may be influenced by environmental factors like cellular temperature.     

Effects of pre-motion electromyographic silent period on dynamic force exertion during a rapid ballistic movement in man

Summary The effects of pre-motion silent period (PSP) on dynamic force exertion were studied in ten healthy subjects performing ballistic elbow extensions. The experiments were designed to evaluate the significance of mean differences between the averaged dynamic force curves of two groups: PSP-presence groups and PSP-absence groups. The presence of PSP was judged quantitatively and automatically by means of a newly developed method using statistical analysis. The results indicated that there were two effects of PSP on dynamic force exertion: one was a reducing effect, observed prior to the movement; the other was a reinforcing effect, observed in the first part of the ballistic movement. The duration of the reinforcement was significantly correlated with the duration of the reducing effect of PSP. The findings suggested that the reinforcement of dynamic force may be produced by the pre-stretch of agonistic muscles caused by prior force reduction due to PSP occurrence. The fact that PSP plays an important role in dynamic force exertion suggests that PSP may be incorporated in the central motor control system designed to interrupt the background activity, to stretch the agonist and to reinforce the dynamic force.     

Computer Imaging Analysis of Glomerular Extracellular Components in Patients with IgA Nephropathy

Computer imaging analysis was used for quantitative evaluation of the extents, amounts and distributions of glomerular extracellular components, such as the 7S and NC 1 domains of type IV collagen, laminin (LN), fibronectin (FN) and IgA, in glomeruli from patients with IgA nephropathy. Renal biopsy specimens from 13 patients with IgA nephropathy were incubated with mouse monoclonal antibodies against the FN or non collagenous (NC 1) domain of type IV collagen or polyclonal antiserum against the LN or 7S domain of human type IV collagen, and then stained with appropriate dilutions of FITC labeled anti mouse Ig antisera. Marked staining of the 7S or NC 1 domain of type IV collagen, LN or FN was detected in the glomerular capillary walls and/or mesangial areas in patients with IgA nephropathy. In particular, a prominent increase of FN was observed in the subendothelial regions of glomerular capillary walls, i.e. mesangial interposition, in the moderate or advanced stage of IgA nephropathy. Therefore, computer imaging analysis was shown to be useful for the quantitative determination of such components distributed in glomeruli from patients with IgA nephropathy. Acta Pathol Jpn 39: 296 305, 1989.     

构建7q32区域鼻咽癌和正常鼻咽上皮细胞部分基因的表达图谱

目的构建７ｑ３２区域鼻咽癌细胞和组织及原代培养人正常鼻咽上皮细胞的部分基因表达图谱。方法通过差异ＲＴ－ＰＣＲ和Ｎｏｒｔｈｅｒｎ杂交的方法检测定位于７ｑ３２区域的２０个ＥＳＴ在鼻咽癌细胞和鼻咽癌组织及原代培养人正常鼻咽上皮细胞ｍＲＮＡ的表达水平。结果８个ＥＳＴ在鼻咽癌细胞ＨＮＥ１和原代培养人正常鼻咽上皮细胞中表达量较一致，７个ＥＳＴ在两种细胞中均无表达，３个ＥＳＴ（Ｗ７２６８８、Ｈ１９８３０、ＡＡ１３０６３０）在鼻咽癌细胞株中表达上调，而２个ＥＳＴ（ＡＡ０７０４３７、Ｈ９０８８２）在原代培养人鼻咽上皮细胞中表达上调。在１３例鼻咽癌活检组织中３０．７％（４／１３）的ＡＡ０７０４３７表达下调，７７％（１０／１３）的Ｗ７２６８８和７７％（１０／１３）的Ｈ１９８３０表达上升。结论构建了７ｑ３２区域鼻咽癌细胞和组织及原代培养人正常鼻咽上皮细胞部分基因表达图谱，并初步认为Ａ０７０４３７的表达下调和Ｗ７２６８８、Ｈ１９８３０的过表达与鼻咽癌的发生有关。     

用小波变换提取视觉诱发电位信号

视觉诱发电位（ＶＥＰ）信号的动态提取及处理具有重要的临床意义。通过硬件采集的ＶＥＰ信号经过叠加平均处理后仍含有大量背景噪声，不能直接用于诊断分析。小波变换是一种新兴时频分析方法，适于分析非平稳信号。在我们研制的视觉生理地形图系统中，成功地用它从背景噪声中提取出ＶＥＰ信号，完成信号的预处理。     

NMDA受体在正常大鼠颈动脉体的表达

应用免疫组织化学方法观察了离子型谷氨酸受体——NMDA受体的NR1及NR2A亚单位在正常成年雄性SD和Wistar大鼠颈动脉体的表达,并对阳性产物的表达强度进行了灰度分析及统计学处理。结果表明:正常成年SD大鼠及Wistar大鼠的颈动脉体内均存在NMDA NR1免疫反应阳性细胞,从阳性细胞的形态和分布特点判断这些阳性细胞为主细胞,两种大鼠之间无明显差异(P>0.05);而两种大鼠的颈动脉体内几乎不存在NMDA NR2A免疫反应阳性细胞。本实验的结果提示:在正常成年大鼠颈动脉体的主细胞上有NMDA受体的分布,并且该受体的二聚体构成不同于经典受体,这可能与谷氨酸在颈动脉体发挥的特殊功能有关。     

基于暗视场荧光图像分析的大鼠微血管流速测量系统的建立

将荧光标记的自身红细胞注入SD大鼠体内,在荧光显微镜下观测标记红细胞在大鼠微血管中的流动情况,并通过显微摄像系统将整个过程以视频信号的形式存贮。使用视频采集卡将流速变化过程回放采样,得到暗视场下的荧光图像。然后利用帧图像分离出奇偶场的图像分析方法测定血流速度。在该系统下测量流动小室中荧光小球的流速,得到的测量值与实际值之间的误差小于7%,两者没明显的差异(P>0.05),流速测量的上限为9.6mm/s。并在大鼠微循环障碍研究中,应用此系统得到了血流速度随时间变化的情况。     

腹主动脉瘤应力模型的建立及其应用

本研究用螺旋CT扫描腹主动脉瘤获得的断层图像合成腹主动脉瘤几何模型，通过设定瘤壁组织生物力学参数和边界条件，使用有限元分析的方法分析腹主动脉瘤瘤壁的应力分布。结果标明，本例腹主动脉瘤应力峰值位于远端分叉部位，瘤体应力峰值位于后壁，均小于瘤壁的承受极限。本研究所得结果对腹主动脉瘤应力模型有助于分析个体化腹主动脉瘤的破裂部位和生长方向，对研究疾病进程提供依据。     

Procedure for the quantitative evaluation of motor disturbances in cerebellar ataxic patients

Cerebellar ataxia is a complex motor disturbance that involves the planning and execution of movements and reduces movement accuracy and co-ordination. The quantification of ataxic signs is commonly realised through visual examination of motor tasks performed by the patient and assignment of scores to specific items composing the international co-operative ataxia rating scale (ICARS). The present work studied an experimental procedure to characterise specific aspects of motor disturbances in ataxia objectively. Four tests belonging to the ICARS were considered: walking, knee-tibia test, finger-to-nose and finger-to-finger test. Through a kinematic analysis performed during the above tests, specific indices were defined to quantify velocity, linearity, asymmetry, tremor, instability and smoothness of movement or posture. The procedure was applied to five patients with cerebellar ataxia and to ten healthy adult subjects. Results demonstrated that the patients moved significantly more slowly than the healthy subjects (0.67 against 0.97 m s⁻¹ and 0.81 against 1.02 m s⁻¹, respectively, for straight walk and finger-to-nose tests) and showed poorer linearity and smoothness behaviour. Velocity, linearity, tremor, smoothness and instability indices showed moderate to good correlation with the corresponding ICARS score. Some of these indices can separately evaluate aspects that are combined in single ICARS subscores. It is concluded that the combination of clinical assessments and instrumental evaluations allows a better insight into ataxic patients' motor disturbances and is a useful tool for the definition and follow-up of rehabilitation programmes.     

9株YONBAN相关TTV变异株全基因序列测定及其结构、分型的研究

目的：对9个TTV新分离株全基因序列测定，基因结构及基因分型的研究。方法：从9名TTV第4基因群感染阳性的婴儿血清中抽提取其DNA，用long inverted PCR扩增出全基因组，克隆和测定全基因组序列，并对测序结果进行计算机分析。结果：首次次测定了TTV第4基因群共9个新分离株的全基因序列，其中8个分离株代表核基因群首次报道的8个新基因型。结论：TTV基因组核酸序列具有高度异质性及基因型的高度多样性，但是，其独特的转录特性和基因组的基本结构在各自的基因群及基因型中十分保守。