Loss of basal forebrain P75(NTR) immunoreactivity in subjects with mild cognitive impairment and Alzheimer's disease.

The long-held belief that degeneration of the cholinergic basal forebrain was central to Alzheimer's disease (AD) pathogenesis and occurred early in the disease process has been questioned recently. In this regard, changes in some cholinergic basal forebrain (CBF) markers (e.g. the high affinity trkA receptor) but not others (e.g., cortical choline acetyltransferase [ChAT] activity, the number of ChAT and vesicular acetylcholine transporter-immunoreactive neurons) suggest specific phenotypic changes, but not frank neuronal degeneration, early in the disease process. The present study examined the expression of the low affinity p75 neurotrophin receptor (p75(NTR)), an excellent marker of CBF neurons, in postmortem tissue derived from clinically well-characterized individuals who have been classified as having no cognitive impairment (NCI), mild cognitive impairment (MCI), and mild AD. Relative to NCI individuals, a significant and similar reduction in the number of nucleus basalis p75(NTR)-immunoreactive neurons was seen in individuals with MCI (38%) and mild AD (43%). The number of p75(NTR)-immunoreactive nucleus basalis neurons was significantly correlated with performance on the Mini-Mental State Exam, a Global Cognitive Test score, as well as some individual tests of working memory and attention. These data, together with previous reports, support the concept that phenotypic changes, but not frank neuronal degeneration, occur early in cognitive decline. Although there was no difference in p75(NTR) CBF cell reduction between MCI and AD, it remains to be determined whether these findings lend support to the hypothesis that MCI is a prodromal stage of AD.     

Estimating neuron dendritic length in 3D from total vertical projections and from vertical slices

The recently developed method of total vertical projections is illustrated to estimate the total dendritic length of a human Substantia Nigra neuron. Next, the length of the different orders of dendritic branches, and the mean segment length for each order - commonly regarded as important parameters in neuron physiology - are also estimated. Finally, it is shown how to estimate the mean dendritic length in a population of neurons from vertical slices of arbitrary and unknown thickness. Being unbiased and highly efficient, the proposed methods offer interesting alternatives to current procedures used for the metric analysis of neuron arborizations.     

计量分析甘草甜素和绞股蓝总苷等对大鼠肝癌前病变的影响

采用被公认的以γ－谷氨酰转肽酶阳性灶（ＧＧＴ＋）为观察终点的二乙基亚硝胺（ＤＥＮ）致大鼠肝癌前病变的模型，对甘草甜素（ＧＬ）、纹股蓝总苷（绞股蓝总甙，ＧＰ）、茶多酚和柴胡水提取液等进行了筛选、并用体现学方法进行计量分析。结果显示，ＧＬ组的ＧＧＴ＋的面数由度（Ｎａ）为２４．１７±１．８３／ｃｍ２（ｘ±Ｓｘ，下同），体密度（Ｖｖ）为４．７４±０．５１％，数密度（Ｎｖ）为３９４．９±４５．２／ｃｍ３；ＧＰ组的Ｎａ为２５．３５±２．６４／ｃｍ２，Ｖｖ为５．９３±０．７５％，Ｎｖ为３７９．２±４８．４／ｃｍ２，这两组的３个估计值与对照组的３个估计值（Ｎａ为３７．２１±２．５６／ｃｍ２，Ｖｖ为８．１２±０．７０％。Ｎｖ为５７６．１±５８．０／ｃｍ３）分别比较时均有显著性差异，说明这两种药物对ＤＥＮ致肝癌发生有抑制作用，而茶多酚和柴胡水提取液则未显示抑制作用。     

Design-based stereological estimation of hepatocyte number, by combining the smooth optical fractionator and immunocytochemistry with anti-carcinoembryonic antigen polyclonal antibodies.

BACKGROUND/AIMS: Hepatocytes (HEP) have been the major target for structural quantification in the liver, but an estimation of their total number (N), their percentage in relation to the global number of liver cells and the evaluation of the percentage of binucleated hepatocytes (BnHEPs) have never been performed with modern design-based stereological techniques. The establishment of sound technical guidelines and baseline quantitative data in non-pathological conditions are relevant to properly evaluate HEP hyperplasia and BnHEP responses. METHODS: In this study, we combined immunocytochemistry with sound design-based stereology for estimating the N of HEP and the N of non-hepatocytic cells (NHCs). For obtaining systematic uniform random sections (30 microm thick), a smooth fractionator sampling scheme was applied to the liver of five male Wistar rats (3 month old). Those sections were immunostained with polyclonal antibodies against carcinoembryonic antigen. Because biliary canaliculi were then marked, an unequivocal counting of mononucleated hepatocytes (MnHEP) and BnHEP was allowed. RESULTS: The N of HEP was estimated to be 1.93 x 10(9), with a coefficient of error (CE) of 0.02, corresponding to 129 x 10(6) HEP/g of liver. BnHEP represented 26% of total HEP number. The N of NHC was estimated as 1.31 x 10(9) (CE=0.02). CONCLUSION: The strategy here presented provides a reliable method for accessing the N of HEP (distinguishing MnHEP from BnHEP) in situations in which these parameters are relevant, namely for evaluating the magnitude of an hyperplastic liver response from its very early onset.     

A stereological study of the human ovarian surface epithelium.

The surface of the ovary has been found to be composed of two types of epithelial cells called A and B cells which are found in their own respective zones, the A and B zones. A quantitative study was undertaken to determine the mean cell volumes and cell ultrastructure. Ovarian biopsies were taken from six women and A and B zones, having been identified by scanning electron microscopy, were re-embedded for transmission electron microscopy. Stereological measurements using point sampled intercepts were made on vertical sections and showed that B cells are significantly larger than A cells. The volume weighted mean cell volumes of the A and B cells were 237.3 microns 3 and 676.8 microns 3 respectively. The volume fractions of the nucleus and mitochondria were similar in the two cell types. Although the vesicle content of each type was similar, a large variation between cases made the interpretation difficult. The stereological tools used in this study proved to be easy and efficient estimators of surface cell ultrastructure and give an important direction for ultrastructural research.     

Ultrastructural mechanisms of myocardial atrophy in albino rats during starvation

Department of Pathomorphology and Morphometry, Institute of Clinical and Experimental Medicine, Siberian Branch, Academy of Medical Sciences of the USSR. Laboratory of Functional Morphology and pathology of the Cell, Institute of Cytology and Genetics, Siberian Branch, Academy of Sciences of the USSR, Novosibirsk. (Presented by Academician of the Academy of Medical Sciences of the USSR V. P. Kaznacheev.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 107, No. 4, pp. 477–481, April, 1989.     

不同年龄人脑视皮质毛细血管密度的计量分析

本文应用碱性磷酸酶染色,按立体学方法观测了不同年龄(14岁以下儿童4例,成年人2例,60岁以上老人2例)共8例人脑视皮质有纹区各层毛细血管的密度(各层均取40个数据).结果:成年组视皮质第三层血管网3c亚层(位于皮质第Ⅳc层)毛细血管密度平均为1580.79±47.73mm/mm~3;儿童组为1087.19±44.90mm/mm~3;老年组为619.95±21.39mm/mm~3.经方差分析检验,P<0.01,说明在第三层血管网3c亚层三个年龄组之间具有非常显著性差异.讨论了各年龄组之间视皮质有纹区毛细血管密度差异与机能的关系.     

白血病MDR细胞系CEM／ADM超微结构改变的定量研究

对人类淋巴细胞性白血病ＭＤＲ细胞系ＣＥＭ／ＡＤＭ及其亲代药敏细胞系ＣＥＭ进行了超微结构的体视学定量比较。结果表明，ＣＥＭ／ＡＤＭ细胞分裂相较多见、核平均体积增大、核畸形严重、异染色质分布更散在、核仁异型性及边集较多见、多数细胞器不发达，说明ＣＥＭ／ＡＤＭ恶性程度更高，ＣＥＭ／ＡＤＭ线粒体平均体积增大与ＭＤＲ主要机制──Ｐ－糖蛋白过度表达而致能量需求增加相关。     

人体乳腺硬癌癌细胞器形态结构的定量研究

目的:区分乳腺正常细胞器和各期乳腺癌细胞器之间的差异,从而建立检查量化指标。方法:本文对女性乳腺硬癌癌细胞器线粒体,溶酶体的16个形态参数进行体视学统计分析。结果:发现癌细胞与正常细胞比较,其线粒体、溶酶体的体积、表面积和面数密度等形态参数存在高度显著差异和显著差异。结论:探讨了癌细胞的线粒体,溶酶体形态变异与功能之间的关系,为乳腺癌临床诊断提供了重要的定量依据。     

Glomerular structure in lithium-induced chronic renal failure in rats

The effects of long-term lithium administration on glomerular structure and intervention with angiotensin converting enzyme inhibitor (ACEI) were studied in rats. Male Wistar rats were fed a lithium-containing diet (Li) or control diet (C) for 16 weeks postnatally. Li-treated rats developed renal failure, hypertension and proteinuria. During the subsequent 24 weeks, subgroups were treated with ACEI. The kidneys were fixed by perfusion, and tissue blocks were serially cut for estimation of glomerular volume and glomerular characteristics by light microscopy. Mesangial and mesangial matrix volume fractions, surface density of capillary walls, basement membrane thickness and foot process width (FPW) were measured by electron microscopy. Glomerular volume was decreased in Li-rats, with increased intra-individual variation. In all Li-rats, some glomeruli (mean 27%) were abnormal, with severe changes in only three rats. Ultrastructural parameters obtained by systematic sampling of three glomeruli in each rat showed no differences among groups. Among Li-treated animals there was a significant correlation between FPW and albumin excretion per unit filtration surface, and between filtration surface per glomerulus and inulin clearance. In conclusion, long-term lithium administration to newborn rats caused marked changes in glomerular volume which were not associated with measurable changes in structural parameters. No effect of ACEI-treatment was detectable.