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101.
Proteins involved in the process of cornification of turtle epidermis are not well known. The present immunocytochemical, electrophoretic and autoradiographic study reports on the localization patterns and molecular weights of keratins, which are cornification proteins, and of tritiated histidine in turtle epidermis. Alpha-keratins with a molecular weight of 40-62 kDa are present in the epidermis. Beta-keratin is mainly detectable in the stratum corneum of the carapace and plastron, but is rarely present or even absent in the corneous layer of limb, tail and neck epidermis. After electrophoresis and immunoblotting with an antibody against chicken scale beta-keratin, bands at 15-17, 22-24, and 36-38 kDa appeared. This antibody recognized weaker bands at 38-40 and 58-60 kDa in the soft epidermis. After reduction and carboxymethylation of proteins extracted from carapace and plastron, but not of proteins from the soft epidermis, protein bands at 15-17 and 35-37 kDa were found when using the anti-beta 1-keratin antibody. Loricrin-, filaggrin-, sciellin-, and transglutaminase-like immunostaining was detectable only in the transitional and lowermost corneous layers of the soft epidermis. Vesicular bodies in the transitional layer were immunolabeled by the anti-loricrin antibody, and weakly by the anti-filaggrin and anti-transglutaminase antibodies. In immunoblots, the anti-loricrin antibody reacted with a major band at 50-54 kDa in both carapace-plastron and soft epidermis. The anti-sciellin antibody detected major bands at 38-40 and 50 kDa in hard epidermis, and at 50 and 54-56 kDa in soft epidermis. Filaggrin-like immunostained bands were observed at 50-55 and 62-64 kDa. This immunostaining was probably due to a common epitope in filaggrin and some keratins. Histidine was evenly incorporated in the epidermis, and the ultrastructural study showed random labeling, often associated with keratin bundles of alpha and beta-keratinocytes. Histidine-labeled protein bands were not found in the carapace-plastron. In the soft epidermis, weakly labeled bands at 15-20, 25, and 45-60 kDa were found occasionally. The latter bands probably represented neo-synthesized keratins as was also indicated by the ultrastructural autoradiographic analysis. In conclusion, our study suggests that proteins with epitopes that they have in common with cornification proteins of mammalian epidermis are also present in the epidermis of turtle. 相似文献
102.
Histogenesis of the duodenum, especially changes in the epithelium in relation to temporal occlusion and re-canalization of
the lumen, was investigated by light microscopy together with morphometric analysis, as well as by scanning and transmission
electron microscopy of 133 externally normal human embryos ranging from Carnegie stage 12 to 23. A series of morphogenetic
events passed the duodenum in a cranio-caudal (proximo-distal) wave like fashion during the period examined. They included:
(1) a decrease in the caliber and area of the lumen, (2) ’occlusion’ of the lumen, (3) vacuole formation, (4) ’re-canalization’
and villi formation. The only exemption to this rule was that, in the upper part of the duodenum, the lumen was not obliterated
in the embryos examined. Morphometric analyses revealed that both the area of the epithelium and the number of epithelial
cells decreased during the ’occlusion’ phase. This result suggests that, unlike the classical view, epithelial cell proliferation
does not play an important role in occluding the lumen, but the predominant morphogenetic event during this phase is convergence
of the epithelial cells to elongate the duodenum. Apoptosis, contrary to some classical views, decreased during the ’re-canalization’
phase, and it appeared to be involved in the formation of the small lumens in the epithelial ’plug’ and in villi formation,
but not in enlarging the secondary lumens. The secondary small lumens in the occluded lumen were frequently formed near the
border between the central ’plug’ and peripheral basal cells on the basement membrane. This and other findings of concentric
differentiation in both the epithelial and mesenchymal layers suggested a possible control mechanism by the epithelium-mesenchymal
interaction on human duodenal morphogenesis and histogenesis. The present electron microscopic observations also provided
details on the mechanisms involved in the enlargement of the secondary lumen and differentiation of villi. The implications
of these findings to duodenal anomalies are also discussed.
Accepted: 12 November 2001 相似文献
103.
Robert Norlund Kjell Grankvist Lena Norlund Inge-Bert Täljedal 《Virchows Archiv : an international journal of pathology》1984,404(1):31-38
Summary Stereological techniques on electron microscopy micrographs were used to evaluate the morphological changes of cultured islet cells that had been exposed to alloxan or 6-hydroxydopamine.Trypan Blue exclusion by cells cultured for 3 days indicated that the cells were 100% viable. Electron microscopy revealed that nearly all of the surviving cultured cells were cells.Exposure to 5 mmol/l alloxan or 1–5 mmol/l 6-hydroxydopamine for 10 or 30 min caused a general swelling of the cultured cells with a concomitant swelling of mitochondria and nuclei. The size of the secretory granules was not affected by the drugs. Only 3–10% of the cells excluded Trypan Blue after exposure to 5 mmol/l alloxan or 6-hydroxydopamine.The data conform with the hypothesis that a primary action of alloxan and 6-hydroxydopamine is at the plasma membrane level of cells.Abbreviations and definitions
A
cell
Cell profile area (µm2), surface area of one cell section surface
-
V
n
Nuclear volume density (%), number of points over the nucleus divided by the number of points over the total cell area × 100
-
V
m
Mitochondrial volume density (%), number of points over mitochondria divided by hits over the cytoplasm (points over the cell minus points over the nucleus) × 100
-
V
g
Granular volume density (%), number of points over granules divided by hits over the cytoplasm × 100 相似文献
104.
Elastofibroma dorsi (EFD) is a relatively rare soft tissue mass, probably of reactive nature. The lesion is typically located near the inferior margin of the scapula or between the inferior part of scapula and the chest wall in elderly women. Although location of the tumor together with the age/sex of the patients and radiologic findings is often suggestive of the diagnosis, tissue examination has been considered necessary to confirm the diagnosis. Although the histologic features of EFD are well known, there are only four single case reports of the cytologic findings in the English language literature. We describe the cytologic features of EFD in five patients with correlations to clinical, radiologic, histologic, and electron microscopic findings. The current study suggests that the fine-needle aspiration (FNA) features are highly diagnostic, permitting a firm diagnosis of EFD in a typical clinical setting and eliminating the need for preoperative histologic examination. 相似文献
105.
用细胞内HRP染色的方法显示该神经元位于猫运动皮层十字沟后,在第Ⅱ/Ⅲ层之间(软膜以下438μm处),胞体截面积为15.6×28.1μm~2,呈多极形,树突呈串珠状,向四周扩展,无侧棘,轴突由胞体下方伸出,返折向上,包绕胞体周围,以软膜平行的吻尾方向行走为主,有一分枝向白质方向延伸.从立体重构图的不同角度观察,其形态不对称,如沿X轴方向旋转60°后,其形态呈扁平形,用胶体金免疫电镜观察,该神经元的递质性质为GABA能的.胞体及树突上分布有非对称型和对称型的突触,对称型的突触中有的是GABA能的,有的是非GABA能的.其轴突有髓鞘包绕,末梢与其它神经元的胞体形成一处以上相连或不相连的对称型突触,也可与其它树突形成对称型的突触.根据该神经元的形态,递质性质及突触分布的特征,可确认它是篮状细胞. 相似文献
106.
H. Shimada K. Noda M. Mori N. Aoki M. Tajima K. Kato 《Virchows Archiv : an international journal of pathology》1994,424(5):569-572
Virions resembling papovavirus were demonstrated in glial cells in the brain of an aged patient without overt progressive multifocal leukoencephalopathy. The patient was not in a severely immunocompromised state. On histological examination, only a few tiny incomplete necrotic foci were found in the subcortical area. These foci were widely dispersed. Rare, swollen oligodendroglial cells and astrocytes in which papovavirus capsid protein (VP-1) was demonstrated immunohistochemically were present around the foci. The two typical types of virus particles i.e. 35 to 40 nm round particles and elongated particles, were observed in the nuclei of the swollen glial cells. The latter were in the minority. Distinct crystals were also found in the nuclei. The centre-to-centre distance of the particles in the crystals, about 40 nm, and the electron-opaque spots of the round-shaped virions and of the elongated particles, were indicative of structural subunits of papovavirus capsids. This case provides further evidence that papovavirus, possibly JC virus, may be reactivated in the brains of aged patients who are not in an immunocompromised state. 相似文献
107.
本文介绍一种具有较高性能价格比的生物医学电镜图像处理系统,该系统以IBM PC/XT,AT或386计算机为主机,图像接口板直接插入机内扩展槽。应用软件可对生物医学图像作图像处理和定量计算。作者通过对人膈腹膜超微结构进行定量分析,为腹水的治疗和腹膜透析(CAPD)等临床医学研究,提供了形态学定量资料。 相似文献
108.
Miodrag ?oli? Nada Pejnovi? Milena Kataranovski Ljiljana Popovi? Sonja Ga?I? Aleksandar Duji? 《Clinical & developmental immunology》1992,2(2):151-160
Rat thymic epithelial cells (TEC) in long-term culture were characterized by
anticytokeratin monoclonal antibodies (mAbs) and electron microscopy. Phenotypic
analysis performed by a large panel of mAbs showed that the highest percentage of
these cells was of the subcapsular/medullary type.
Recombinant rat interferon (IFN)-gamma up-regulated class-I and class-II MHC
expression by TEC in culture as confirmed by immunohistochemistry and flow
cytometry, but did not significantly alter other cell markers. TEC supernatants of IFN-gamma-
treated cultures showed higher interleukin-6 (IL-6) activity, compared to the
control, as determined by proliferation of the IL-6-sensitive B9-cell line. Increased IL-6
activity was probably not a consequence of increased TEC number in IFN-gammatreated
cultures because IFN did not significantly stimulate TEC proliferation in vitro. In
contrast, IL-6 significantly stimulated TEC proliferation, indicating that this cytokine is
not only a regulatory molecule for T-cell proliferation, but could also be an autocrine
growth factor for thymic epithelium. 相似文献
109.
110.
采用免疫组化及免疫电镜技术对临床胃粘膜活检及胃癌手术标本进行了纤维连结蛋白(FN)的定位观察。结果,FN见于胃粘膜上皮细胞和部分癌细胞内以及各种基底膜、间质中。肠化及异型增生上皮细胞FN染色增强,胃癌细胞和其基膜FN减少缺失且与癌细胞分化程度相关,胃癌间质FN丰富,尤其以癌浸润前缘明显。本文着重讨论了胃癌FN改变与癌细胞生物学特性的关系。 相似文献