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Extensive changes in cytokeratin expression patterns in pathologically affected human gingiva 总被引:4,自引:0,他引:4
Franz X. Bosch Jean-Pierre Ouhayoun Bernhard L. Bader Christine Collin Christine Grund Inchul Lee Werner W. Franke 《Virchows Archiv. B, Cell pathology including molecular pathology》1989,58(1):59-77
The stratified squamous epithelium of the oral gingiva and the hard palate is characterized by a tissue architecture and a cytoskeletal composition similar to, although not identical with, that of the epidermis and fundamentally different from that of the adjacent non-masticatory oral mucosa. Using immunocytochemistry with antibodies specific for individual cytokeratins, in situ hybridization and Northern blots of RNA with riboprobes specific for individual cytokeratin mRNAs, and gel electrophoresis of cytoskeletal proteins of microdissected biopsy tissue samples, we show changes in the pattern of expression of cytokeratins and their corresponding mRNAs in pathologically altered oral gingiva. Besides a frequently, although not consistently, observed increase in the number of cells producing cytokeratins 4 and 13 (which are normally found as abundant components in the sulcular epithelium and the alveolar mucosa but not in the oral gingiva) and a reduction in the number of cells producing cytokeratins 1, 10 and 11, the most extensive change was noted for cytokeratin 19, a frequent cytokeratin in diverse one-layered and complex epithelia. While in normal oral gingiva cytokeratin 19 is restricted to certain, sparsely scattered cells of --or near--the basal cell layer, probably neuroendocrine (Merkel) cells, in altered tissue of inflamed samples it can appear in larger regions of the basal cell layer(s) and, in apparently more advanced stages, also in a variable number of suprabasal cells. Specifically, our in situ hybridization experiments show that this altered suprabasal cytokeratin 19 expression is more extended at the mRNA than at the protein level, indicating that cytokeratin 19 mRNA synthesis may be a relatively early event during the alteration. These changes in cytokeratin expression under an external pathological influence are discussed in relation to other factors known to contribute to the expression of certain cytokeratins and with respect to changes occurring during dysplasia and malignant transformation of oral epithelia. 相似文献
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B. D. Mowrey D. J. Werner 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1990,80(1):129-133
Summary An isozyme survey of 34 species of Prunus representing subgenera Prunus, Amygdalus, Cerasus, and Lithocerasus detected 110 presumptive alleles at 11 isozyme loci. Principal component analysis was conducted on the covariance matrix derived from allelic frequencies calculated for each species. Cluster analysis was performed on the first 30 principal components. Results generally support traditional classification of Prunus at the subgeneric level, except for members of subgenus Lithocerasus and two members of subgenus Amygdalus. Prunus glandulosa Thunb., P. japonica Thunb., and P. tomentosa Thunb. of subgenus Lithocerasus and P. triloba Lindl. of subgenus Amygdalus appear to represent primitive species. P. besseyi Bailey and P. pumila L. of subgenus Lithocerasus and P. andersonii of subgenus Amygdalus should be assigned to subgenus Prunus. Placement of its members indicates that subgenus Lithocerasus is an artificial grouping of species that are very different genetically although similar phenotypically.Paper No. 12529 of the Journal Series of the North Carolina Agricultural Research Service, Raleigh, NC 27695-7643, USA 相似文献
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The sorption and desorption of water in rape seeds was measured. From the sorption isotherm it follows that for water content greater than about 6% the water molecules tend to form clusters. The mutual diffusion coefficient of water into and out of the seeds was determined from the time dependence of sorption and desorption. There is a pronounced hysteresis in the sorption-desorption process, desorption proceeds faster than sorption. The self-diffusion of water (at maximum humidity of the seeds) and oil within the seeds was investigated by the pulsed field gradient NMR. The measurement of oil self-diffusion shows restricted diffusion of the oil within droplets and allows the determination of the droplet radii and their distribution width. 相似文献
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Georges Vauquelin Hilde De Vos Jean-Paul De Backer Guy Ebinger 《Neurochemistry international》1990,17(4)
The antagonist [3H]idazoxan binds with comparable affinity to α2 adrenergic receptors and to phentolamine-displaceable non-stereoselective sites in human frontal cortex membranes. In contrast, idazoxan analogs possessing alkyl and alkoxy substituents at the 2-position of the benzodioxan moiety (i.e. RX 821002: 2-methoxy-1,4-[6,7-3H]benzodioxan-2-yl-2-imidazolin HCl, 43.8 Ci/mmol) possess 300–1200 times lower affinity for the non-stereoselective sites. Their affinity for the α2 receptors is increased as well, resulting in more than a 1000-fold selectivity towards the receptors as compared to the non-stereoselective sites. [3H]RX 821002, the 2-methoxy analog of idazoxan possesses an approx. 10-fold higher affinity for the α2 receptors (KD = 2.8 nM than [3H]idazoxan (KD = 24 nM) and about equal affinity as [3H]rauwolscine (KD = 3.6 nM).[3H]Rauwolscine binds with comparable affinity to α2 receptors and to 5-HT1A receptors, and competition studies indicate that the Ki value of unlabelled RX 821002 for the 5-HT1A receptors (30 nM) is about one order in magnitude above its Ki value for the α2 receptors (4.1 nM). Labelling of the 5-HT1A receptors by [3H]RX 821002 and by [3H]rauwolscine can be prevented by selective masking with 8-OH-DPAT (30 nM) or 5-HT (0.3 μM). Under these conditions, specific binding of [3H]RX 821002 to the α2 receptors represents 84% of total binding (at its KD), as compared to 77% for [3H]rauwolscine and 20% for [3H]idazoxan.[3H]RX 821002 labels the α2 receptors as a single class of non-cooperative sites. Association and dissociation kinetics are very fast at 37°C. Antagonist competition curves are steep with Hill coefficients close to one and the agonist curves can be analysed in terms of two affinity sites, confirming the antagonistic properties of [3H]RX821002. About 60% of the α2 receptors possess high agonist affinity. 相似文献
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