摘要:

The morphology and distribution of intercellular junctions were studied in the clinically normal junctional epithelium of dogs by freeze‐fracture and thin sectioning. Desmosomes were found in cells of the coronal and apical regions of the junctional epithelium. The occurrence values for desmosomes were low in comparison with those of other oral epithelia. Gap junctions were also observed in cells of the junctional epithelium, often in association with desmosomes. These were usually small, their diameter varying between 0.2 and 0.7 μm. Relatively large ones were found in the cells of the coronal region. Tight junctions were observed only in the intermediate cells of the coronal region, forming small, discretemaculae occludentes.Numerous dense PTA‐positive granules were observed in the peripheral cytoplasm of the intermediate and superficial cells. In freeze‐fracture replicas, hemispherical structures were also observed at the periphery of the cytoplasm. Because of similarities in their size and location, the hemispherical structures probably correspond to the dense granules. Freeze‐fracture images such as elevated membranes seem to reveal exocytosis. The hypothesis is put forward that the dense granules are related to the physiological permeability barrier in the junctional epithelium. However, it is doubtful that the epithelium provides a complete barrier function because of the vast extent of the intercellular spaces and the sparseness of de

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1981.tb02012.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

Sulcular penetration patterns of phenytoin (PHT) and albumin (BSA), in New Zealand white rabbits, were followed through the sulcular lining tissue, overlying gingiva, interposed connective tissue, proximating periosteum and blood over 180 minutes. The time course study revealed that a steady‐state uptake of both molecules from the sulcus into the sulcular lining tissue was reached approximately 60 minutes after local tracer application. It was also found that PHT, after penetrating the sulcular lining tissue, was maintained at higher levels in gingiva than in other adjacent tissues while BSA levels were found highest in periosteum. Kinetic studies of these tissues demonstrated that sulcular tissue had a greater capacity for PHT than BSA and that uptake by this tissue had a capacity‐limited characteristic. The other adjacent tissues and blood also showed capacity‐limited characteristics probably reflecting uptake by the sulcular tissues. BSA degradation or PHT metabolism did not occur in any of these tissues or in

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1981.tb02013.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

The metabolism of progesterone in the oral mucosa of the rat was investigated. Homoge‐nates and mitochondrial, microsomal, and soluble fractions were obtained with differential centrifugation. The subcellular preparations were supplemented with NADPH and incubated with14C‐progesterone for 30 min at pH 7.4 and 37°C. The metabolites were identified by column, multiple thin‐layer chromatography and radioautography and quantified with liquid scintillation counting. The subcellular preparations of female and male rat oral mucosa were found to metabolize progesterone. Differences between both sexes were detected. The metabolism was less in the male than in the female preparations. On the basis of the identified metabolites it can be concluded that the oral mucosae of both sexes contain marked 3α‐3β, and 20α‐hydroxysteroid dehydrogenase, δ4‐5α‐ and δ4‐5β‐steroid hydrogenase activities, and also small 20β‐hydroxyst

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1981.tb02014.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

In this study we investigated the possible role of the junctional epithelium of the mouse incisor in the degradation of collagen fibers carried during eruption from the periodontal ligament into the gingiva. To eliminate the contribution of fibroblasts to collagen breakdown the periodontal ligament was frozen in the sub‐crestal region by local application of liquid nitrogen. As a result of this treatment the fibroblasts were disrupted and, with ongoing eruption, the ligament was split into two separate sets of collagen fibers, one attached to the incisor and the other to the alveolar bone. The injured connective tissue in the tooth‐related compartment continued to move in the occlusal direction and made contact with the intact gingiva. Following its arrival in the sub‐epithelial region, the collagen fibers were not degraded but carried further towards the incisal edge, a process resulting in a forward shift of the level of connective tissue attachment. The degree to which this occurred was inversely proportional to the number of fibroblasts which had repopulated the connective tissue adjacent to the incisor. The data suggest that degradation of collagen and maintenance of connective tissue attachment in mouse incisor gingiva cannot solely be performed by cells of the junctional epithelium but require primarily the degradative activity of fibrob

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1981.tb02015.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

Strains of a newBacteroidesspecies were isolated from three cases of severe localized periodontitis in adults, in which the organism comprised greater than 50 % of the cultivable subgingival flora. The isolates were Gram‐negative, obligately anaerobic short rods, which required CO2for growth. The strains were esculin‐positive, oxidase– and gelatinase‐negative, and produced acid from a variety of carbohydrates, including arabinose, xylose, raffinose, rhamnose, and cellobiose. The major acid end–products from glucose were acetic and succinic acids. The isolates all possessed an extra‐layer external to the outer membrane, as well as an extensive fibrous or hair‐like network of intensely staining, ruthenium red, and malachite green material, indicative of a glycolipid or a glycolipoprotein polymer. The physiological and ultrastructural observations are discussed in relation to other known bacteroides and show these isolates to be representative of a newBacteroidesspecies namedBactero

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1981.tb02016.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

The purpose of this study was to examine the effects ofActinomyces viscosusandFusobacterium nucleatumsonicates on antibody formation in vitro and to elucidate their mechanisms on the cellular basis. Suspensions ofA. viscosusandF. nucleatumwere sonicated, and the supernatant was filtered and heated. After AKR mouse spleen cells were stimulated with sheep red blood cells, the antibody formation was assayed by counting the plaque‐forming cells (PFC). Macrophages, T‐ and B‐cells were harvested from the mouse peritoneal exudate and spleen. Mitogenicity of the sonicates was determined by counting the uptake of3H‐thymidine.The PFC number, whenA. viscosusorF. nucleatumsonicate was added, increased significantly by 2.4–6.6 times more than the control. Two sonicates were found to activate the macrophages, resulting in an increase of PFC.F. nucleatumsonicate was effective to PFC response via activation of helper T‐cells. Stimulation index ofF. nucleatumsonicate on T‐cells was 4.1 and that ofA. viscosussonicate on B‐cells was 3.2. In conclusion, the enhanced antibody formation byA. viscosussonicate depends on the activation of macrophages and B‐cell mitogenicity, and theF. nucleatumsonicate enhances the PFC response by activation of both macrophages and helper T‐cells and by T

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1981.tb02017.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

The overall aim of this work was to analyze the role of the immune response to a known periodontal pathogen,Actinomyces viscosusT14V, in orally superinfected Balb/c mice. The mice did not containA. viscosusin the oral cavity prior to superinfection. Colonization by superinfectingA. viscosuswas specific for the tooth surface.When mice were placed on a soft, high‐carbohydrate diet and superinfected with varying doses ofA. viscosusT14VJ1, all mice became infected. A cell‐mediated response to the bacteria was detected only in the low‐dose inoculated animals, and only the low‐dose mice developed bone loss. No serum antibody to the bacteria was detected in any animal. The response to the bacteria was detected in the cervical lymph nodes, which are the draining lymph nodes for the gingival tissue. The results suggest that the development of an immune response to the periodontal pathogen,A. viscosusT14V, correlated with bone loss in super‐infe

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1981.tb02018.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

Human gingival tissue biopsies were classified as “initial or early” or “established or advanced” periodontal lesions on the basis of the histopathological criteria of Page and Schroeder (1976). They were then examined for the ability to fix complement by the anticomplement immunofluorescence technique which detects fixation of exogenously applied guinea pig complement. Complement fixation was found in association with IgG deposits (detected by immunohistochemical staining) in 80 % of the established and advanced lesion, thus suggesting that it was fixed by immune complexes or aggregated IgG. The complement fixing activity was not associated with IgA or IgM deposits. In contrast, less than 13 % of the initial and early lesions were found to contain such activity. The presence of complement fixing activity was thus found to be significantly correlated with the more advanced as opposed to the earlier stages of periodontal inflammation (p = 0.02 by Chisquare an

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1981.tb02019.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

Phenotypic characterization of lymphoid cell subpopulations in gingivitis associated with the deciduous dentition in children was carried out. Biopsies were obtained from 10 children aged between 5 and 9 years. The tissues were processed for either histochemistry or for immunofluorescence. T‐cells were identified by their T‐enzyme staining pattern and lack of immunoglobulin. B‐cells on the other hand were identified by their lack of T‐cell enzymes and presence of surface or cytoplasmic immunoglobulin. Morphologically the lesions consisted of approximately 70 % lymphocytes, between 11 and 26 % macrophages and fewer numbers of polymorphonuclear leukocytes and plasma cells. The majority of lymphocytes (approximately 70 %) were T‐enzyme positive/Ig negative indicative of a Tcell population. Approximately 12 % of the infiltrating cells were immunoglobulin positive. These results showed that gingivitis in children is essentially a T‐cell lesion and supports the hypothesis that the conversion from a stable to a progressive lesion involves shifts in cell

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1981.tb02020.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1981.tb02021.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY