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1.
G. M. Halliday L. Davies D. A. McRitchie H. Cartwright R. Pamphlett J. G. L. Morris 《Acta neuropathologica》1995,90(1):68-75
A 66-year-old woman presented with an alien limb syndrome without dementia. The course of her illness was unremitting and at autopsy 6 years later her diagnosis was confirmed as corticobasal degeneration without Alzheimer-type pathology. Although the presence of ballooned achromatic cortical neurons and cell loss from the substantia nigra distinguishes such patients, the site and density of achromatic neurons has not previously been quantified. We show that immunohistochemistry for the cell stress protein ubiquitin selectively stains these achromatic neurons, whereas they do not stain for abnormally phosphorylated tau protein. Phosphorylated neurofilament antibodies recognise both ballooned and non-ballooned neurons. In this case, high densities of ubiquitin-positive ballooned neurons were found in frontal cortical regions with the highest densities in layers V and VI of the anterior cingulate cortex. In addition, high densities of ubiquitin-positive ballooned neurons were found in the insular cortex, claustrum and amygdala. These results confirm past reports of frontal pathology, but show that there is also considerable pathology in insular and parahippocampal cortical regions and some subcortical regions. Our findings suggest that the distribution and staining characteristics of ballooned neurons in corticobasal degeneration may help to differentiate these cases pathologically, while the absence of dementia appears to be an important clinical criterion. 相似文献
2.
Anna Plachcinska Jacek Kusmierek Maciej Kosmider Malgorzata Bienkiewicz Julian Liniecki 《European journal of nuclear medicine and molecular imaging》1995,22(3):193-200
A quantified evaluation of planar cardiac perfusion scintigrams (the objective of the study), obtained using technetium-99m methoxyisobutylisonitrile (MIBI) was performed on the basis of an analysis of circumferential profile curves, representing the perfusion as seen in three typical projections. The analysis involved the curves obtained both at rest and after stress, and was based on a comparison of their shape (trend) with the normal trend (normative evaluation). The latter was obtained by means of an original method of iterative fitting of individual curves into the database. The base consisted of curves recorded in 53 patients (separately in males and females) with normal perfusion of the left ventricle (group I, the reference group). A group of 90 patients suspected of having coronary artery disease (group II) was subdivided into two subgroups on the basis of coronary arteriography: (a) those with and (b) those without critical stenosis of at least one artery. Profile curves characterising the LV perfusion were obtained at rest and after stress. Defects of perfusion were quantified by comparison of individual curves with the normal trends. By means of multivariate analysis it was demonstrated that vectors of mean values characterising the scintigraphically assessed defects of LV perfusion in the two subgroups of group II differed very significantly (P<10–5). Applying methods of discriminant analysis, a classification of patients from group II was performed into those with probable defects of perfusion and those free of such defects. The sensitivity, specificity and accuracy of diagnosis of coronary ischaemia, based on quantified planar99mTc-MIBI scintigraphy, reached 86%, 87% and 87%, respectively. 相似文献
3.
4.
Andrew E. Todd-Pokropek 《Brain topography》1992,5(2):119-127
Summary The use of tracers is an important technique available for studying cerebral function. Changes in signal are large, but as a result of its photon limited nature, the measurement of this signal is limited: spatially, temporally and in terms of accuracy. The most commonly used single photon (SPECT) system (as apposed to positron) is that with a rotating gamma camera, although multi-headed devices and special purpose rings are now also commonly available. The problems of obtaining good functional information are however identical. Firstly the devices need to be optimised in terms of resolution and sensitivity. Secondly several sources of error, notably those associated with scatter, attenuation and limited spatial resolution, need to be corrected, with the aim of obtaining quantitative estimates of radioactivity concentration. Finally such quantitative estimates need to be converted into meaningful estimates of physiological variables by use of an appropriate model. The general aim of many SPECT measurements is to estimate blood flow for example using Tc-99m labelled HMPAO as a tracer. Good results have been obtained in many clinical conditions: stroke, dementia, tumour and epilepsy, for example. Many other tracers are also available, for example to measure density of receptor sites. The use of SPECT in conjunction with other techniques after image registration is suggested as being an essential tool in extracting maximal clinical information. 相似文献
5.
The aim of this study was to determine the number and size of apical non-myelinated (C) axons of healthy human premolars. The material was derived from a large collection of specimens prepared for a previous quantitative investigation on the myelinated (A) axons of human premolars. A total of 16 teeth (six maxillary first and five each of mandibular first and second premolars), removed from adolescents for orthodontic reasons, were used. Root discs of about 0.6 mm thickness were prepared at about 2 mm cervical to the root apex and processed for light and electron microscopy. The number of non-myelinated axons was determined by taking a total census of such fibres that could be identified and reconstructed by standardized composite electron micrographs from each root disc. The measurement of axons was done on a statistically representative sample of axons (n=1810) using an electronic image processing unit. The 16 teeth had an average of 2000 ± 1023 non-myelinated axons at the juxta-apical level (range 534–3912). The average diameter of the non-myelinated axons was found to be 0.5 ± 0.4 m (range 0.05–2.4 m). 相似文献
6.
Summary The primary objective of this study was to determine the number and size of myelinated nerve fibers at the subcervical, midroot and juxta-apical levels of human premolars. Sixty-seven healthy premolars extracted from adolescents were utilized. Root-discs were prepared from the three sites and processed for light and electron microscopy. The myelinated nerve fibers were counted from semithin sections using a sampling microscope. The measurements were taken from composite electron micrographs using an electronic image processing unit. A total of 1883 myelinated axons from seven mandibular second premolars was gauged. The 67 teeth had an average of 312±149 myelinated nerve fibers at the juxta-apical level (range 18 to 728). The contra- and ipsilateral differences in means among the four groups of premolars were not significant (P>0.05). The number of nerves increased significantly (P<0.05) toward midroot and subcervical (P<0.001) levels in all groups. The average neural diameter was 3.51.0 m at the juxta-apical level, and the between-teeth difference in mean was found to be significant (P<0.01). There was no decline (P>0.05) in the diameter of myelinated nerve fibers toward midroot and subcervical levels. 相似文献
7.
Abstract An enzyme-linked immunosorbent assay (ELISA) was developed for quantitation of antibodies to Toxoplasma gondii in swine sera. Because a commercial anti-swine IgG conjugate was directed also against swine IgM, the conjugate was absorbed with the IgM fraction to eliminate the interference of naturally occurring IgM antibodies that appeared consistently in sera collected from slaughtered pigs at an abattoir. The ELISA values of 0.2 or more observed in most of the sera successfully decreased to less than 0.2 by the use of absorbed conjugate. An attempt to use a protein A conjugate has failed. Evaluation of this system by comparing it with the latex agglutination test provided a high significant correlation, indicating its usefulness for serodiagnosis of swine toxoplasmosis. 相似文献
8.
目的通过绝对定量分析健康青年人服用磷酸可待因后双侧前额叶及海马代谢物浓度变化,为下一步研究青年人可待因慢性成瘾机制提供前期实验数据参考。材料与方法正常健康青年志愿者20名,男10名,女10名,年龄18~30岁,平均(24.9±1.9)岁,均为右利手,无神经、精神疾病病史。采用GE 1.5 T Signa HDX超导MR扫描仪,单体素1H-MRS PRESS序列,TR 3000 ms,TE 30 ms,矩阵256×128,NEX为1,感兴趣区置于双侧前额叶及双侧海马,大小2 cm×2 cm×2 cm,采集服药前及口服60 mg磷酸可待因后1.0~2 h内的实验数据,利用LCModel软件对采集的数据进行后处理及定量,用SPSS19.0配对样本t检验进行统计学分析。结果服用磷酸可待因后左前额叶脑代谢物发生改变,甘油磷酸胆碱(GPC)浓度增加0.254 mmol/L、肌醇(Ins)浓度下降0.988 mmol/L,差异有统计学意义(n=13,P0.05;n=12,P0.05);右前额叶、双侧海马的代谢物浓度改变无统计学差异。结论口服磷酸可待因能引起左前额叶代谢物的改变,GPC浓度上升与Ins浓度下降可能与急性用药后前膜递质释放减少有关。 相似文献
9.
Campbell Roberts SN Williams AC Grimsey IM Booth SW 《Journal of pharmaceutical and biomedical analysis》2002,28(6):4644-1147
Mannitol is a polymorphic excipient which is usually used in pharmaceutical products as the beta form, although other polymorphs (alpha and delta) are common contaminants. Binary mixtures containing beta and delta mannitol were prepared to quantify the concentration of the beta form using FT-Raman spectroscopy. Spectral regions characteristic of each form were selected and peak intensity ratios of beta peaks to delta peaks were calculated. Using these ratios, a correlation curve was established which was then validated by analysing further samples of known composition. The results indicate that levels down to 2% beta could be quantified using this novel, non-destructive approach. Potential errors associated with quantitative studies using FT-Raman spectroscopy were also researched. The principal source of variability arose from inhomogeneities on mixing of the samples; a significant reduction of these errors was observed by reducing and controlling the particle size range. The results show that FT-Raman spectroscopy can be used to rapidly and accurately quantitate polymorphic mixtures. 相似文献
10.
BACKGROUND: Tissue factor (TF) is primarily known for its function to initiate blood coagulation. The range of in vivo expression of TF is wide and requires a dynamic assay for monitoring. A general method for TF mRNA quantitation that is dynamic, sensitive and applicable to a variety of experimental systems or clinical situations is therefore desirable. OBJECTIVES: To develop a method for sensitive and dynamic quantitation of TF mRNA in human blood cells. METHODS: TF mRNA expression was analysed and evaluated in monocyte isolations, in whole blood (healthy volunteers and patients scheduled for percutaneous coronary intervention, PCI) and in a panel of human cell lines. RNA was extracted, reverse transcribed and subjected to real-time PCR amplification, according to the TaqMan technology. A TF plasmid was constructed as calibrator of the assay. Two housekeeping genes used as endogenous controls for cDNA quality and integrity were evaluated. RESULTS: The assay was linear by seven orders of magnitude and detected down to 10(2) copies of the TF plasmid. The coefficient of variation was 4% intra-assay and 28% between the assays when using beta2MG as endogenous control. The beta-actin gene expression was induced by treatment with lipopolysaccharide (LPS) in blood leukocytes and could not be used as an endogenous control. However, beta2MG showed only minor variations upon treatment with LPS. The TF mRNA and antigen expression, measured in a Western blot, correlated well (R(2)=0.903) in a panel of 11 human cell lines. CONCLUSIONS: We have established a method for sensitive and dynamic quantitation of TF mRNA in experimental systems and for clinical situations. 相似文献