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K Rossinsky

Publications and source records attributed to K Rossinsky.

9 recordsLinked to original sources
PubMed1989

Human junctional epithelium as a pathway for inflammatory exudation.

Photographic montages of transmission electron micrographs of the dentogingival region have made it possible to assess the morphologic alterations that occur in the junctional and the oral sulcular epithelium as a result of mild gingival inflammation. Enlargements of the intracellular spaces in the junctional epithelium varied in size and shape from isolated alveolate enlargements, often containing isolated granulocytes, to channel-like pathways oriented in an apico-coronal direction and frequently filled with rows of granulocytes. In contrast to artifactitious spaces, these enlarged intercellular spaces failed to reveal the presence of ruptured intercellular bridges and contained well preserved undistorted granulocytes with round profiles. Moderately electron dense material within the enlarged intercellular spaces probably represented proteins from the fluid exudate, precipitated by the fixation process. The rate of normal junctional epithelial turnover appeared to be insufficient to compensate for the above morphological alterations brought about by the inflammatory process. Mononuclear cells, mostly lymphocytes, were preferentially located in the connective tissue side of the junctional epithelium. Their low numbers in the gingival sulcus suggest that they are passively carried into the sulcus as a result of normal turnover of the junctional epithelium, whereas granulocytes, which account for the majority of leucocytes in the sulcus, actively migrate through the junctional epithelium.

Bicuspid↗
PubMed1989

[Sulcus and coronal junctional epithelium in mild gingivitis. A retrospective study].

Is the presence of mild gingivitis in humans synonymous with early pocket formation? In order to answer this question, buccal gingival biopsies from 5 children, 9 to 12 years of age, were studied by light and electron microscopy. These biopsies included the entire topographically intact gingival sulcus and coronal junctional epithelium. The results indicated that in the presence of supragingival plaque and mild gingival inflammation, the coronal junctional epithelium acquired a loose structure. However, this structural change did not affect the ability of the junctional epithelium to maintain its attachment to the tooth. The loose epithelial structure results in part from the apico-coronal migration of neutrophilic granulocytes through the junctional epithelium and the appearance throughout the junctional epithelium of irregular, cavernous enlargements of the intercellular spaces that are filled with tissue fluid. The degree to which the epithelial structure is altered varies over short stretches of the dentogingival junction. The findings are interpreted in the light of current knowledge in pathophysiology. The above question appears to have a negative answer.

Child↗
PubMed1985

Organization of lymphoid tissue in the tonsilla lingualis. An ultrastructural study in Macaca fascicularis (Primates, Cercopithecoidea).

Lymphoid organs are highly organized structures made up of different tissue compartments, each with its own specific cell populations. However, the cellular elements of the lingual tonsil, which forms a significant part of Waldeyer's pharyngeal ring, are not yet documented. This study, therefore, describes the fine structure and tissue organization of tonsilla lingualis in Macaca fascicularis. Ten selected crypto-lymphatic units originating from five perfusion-fixed animals were analysed ultrastructurally. Based on the fine-structural elements contained within, the lymphoid tissue of tonsillar units could be subdivided into follicular (germinal centre) and parafollicular areas. The latter contained predominantly small lymphocytes, lymphoblasts resembling T-blasts, plasma cells, macrophages, occasional neutrophils and many reticular cells resembling fibroblasts. A distinct feature of the parafollicular area was the presence of numerous high endothelial (HEV)- or postcapillary venules (PCV). The follicular areas contained many small and large lymphoid cells, mitotic cells, plasmablasts, macrophages and specialised reticular cells resembling follicular dendritic cells (FDC) with distinct desmosomal junctions. These observations show that the crypto-lymphatic units of the lingual tonsil are, in fact, organised into distinct B- and T-cell compartments with their own specific lymphoid and accessory cells.

Animals↗
PubMed1984

Crypt architecture of tonsilla lingualis in the monkey, Macaca fascicularis. A correlated light- and scanning electron-microscopic study.

Crypts of the lingual tonsil were investigated in 10 male and female Macaca fascicularis by use of correlated light- and scanning-electron microscopy. Counting of crypt openings provided an estimate of the total number of respective crypto-lymphatic units, which were found to range from 20 to 39. Crypt openings appeared in three distinct morphological varieties, i.e. circular, oval or slit-like. Tonsillar units existed individually or were arranged in a rosary fashion below a slit-like mucosal fold serving as a common exit. Although the crypt epithelium was generally non-keratinized, individual cells showing a surface pattern similar to that of the keratinized cells could be encountered. The crypt epithelium was frequently fragmented and showed heavy mononuclear cell infiltration and surface discontinuities, with lymphoid cells coming in contact with luminal contents. The crypt lumen either appeared as a simple epithelial invagination or existed as a complex, cavernous pouch with many blind-ending diverticula. The lumen contained a mixture of exfoliated epithelial cells, leucocytes and bacteria. The secretory ducts of the posterior lingual glands opened occasionally at various levels into the crypt lumina or independently to the exterior.

Animals↗
PubMed1980

An established routine method for differential staining of epoxy-embedded tissue sections.

A method is described for staining semithin sections of epoxy-embedded cells and tissues. PAS-positive structures are specifically demonstrated by a red staining providing a vivid contrast to the other tissue components differentially stained in shades of blue, using methylene blue/azure II. Typical staining conditions for 1 to 2 micron thick Epon sections include 30 min oxidation with 5% periodic acid at 50 degrees C, 30 min incubation with Shiff's reagent at 50 degrees C, 20 min counter-staining with 0.5% methylene blue/0.5% azure II in 0.5% aqueous borax solution at room temperature. For 10 years, this method has provided excellent differential staining with a variety of tissues. Stained sections showed no signs of fading during this period of time. Therefore, this procedure is recommended as a simple method of staining semithin sections both for tissue orientation in electron microscopy and for brillant representation of cells and tissues, required for microphotography in color or black-and-white.

Animals↗