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H Magloire

Publications and source records attributed to H Magloire.

85 records · Page 5Linked to original sources
PubMed1982

Distribution of type III collagen in the pulp parenchyma of the human developing tooth. Light and electron microscope immunotyping.

The distribution of collagen type III throughout the pulp tissue from human developing tooth was studied using specific antibodies, immuno-fluorescence as well as immuno-peroxidase labelling for electron microscopy. Our results indicate that type III and type I collagen are present in the pulp. The staining intensity seems to correlate with the relatively high proportions of type III collagen biochemically found in pulp. In addition, type III collagen and reticulin fibres are similarly distributed, except that the Von Korff fibres were never detected with anti-type III collagen antibodies. Correspondingly, at the ultrastructural level, type III collagen appears as fine, branched filaments or electron dense material distributed throughout the tissue and particularly in close association with the plasma membrane of pulp fibroblasts. In contrast, type I collagen appears as typical coarse cross banded fibres.

Adolescent↗
PubMed1981

Immunohistochemical localization of type I, III and IV collagen in healthy human gingiva.

The distribution of type I, III and IV collagen in the gingival connective matrix was studied by indirect immunofluorescent techniques on biopsies of healthy human attached gingiva. This connective matrix would seem to be made up of an intricate pattern of these 3 collagen types. Type I collagen is the main component of all the layers of the gingival corium while type III collagen is mostly found in the upper layers underlying the gingival epithelium and within the blood vessel walls. Type IV collagen is only associated with basement membranes, particularly of the gingiva, endothelial cells of capillaries, blood vessel walls and nerves.

Adult↗
PubMed1980

[Supplemental data to the ultrastructural study of Trichomonas tenax. Intra-cellular distribution of acid phosphatase].

In scanning electron microscopy, the flagella come out from the cellular body following different configurations: either separately or in groups. The undulating membrane lasted up to 2/3 of the cell body: at its end the recurrent flagella seems to penetrate again into the cell. The costa starts from the cinetosome of the recurrent flagella: the two parabasal filaments start from two different cinetosomes and follow the costa for a small distance. The nucleus is surrounded by a membrane which is not always visible. The axostyle has a cylindrical shape in the posterior two thirds of the cell. Bacteria at different stages of phagocytosis have been observed. The acid phosphatase is localized in the saccules and vesicles of the Golgi apparatus, in the lysosomes and phagolysosomes and in the terminal lamina of the undulating membrane.

Acid Phosphatase↗
PubMed1979

Electrophysiological properties of human dental pulp cells.

Resting membrane potentials and electrotonic potentials of human dental pulp cells (peripheral and inner cells) were recorded from intracellular measurements. The results show a high resting membrane potential (- 80 mV) for peripheral cells and a low resting membrane potential (- 30 mV) for inner cells. The peripheral cells present rectification properties (outward going rectification and delayed rectification) and a negative post potential at the end of the depolarizing current. These properties are similar to those found in some receptor cells. On the basis of their morphological characteristics, these peripheral cells are compared to odontoblasts in their early stage of development.

Adolescent↗
PubMed1979

Fine structural observations of calcium storage in human dental pulp cells in primary culture.

Primary culture of explants of human dental pulp tissue allows the study of the cytophysiology and differentiation of the cultured cells over a two-week period. The distribution of calcium was found in two different experimental conditions : with and without a calcium loading, by mean of a lead technique checked by microprobe analysis. The existence of two cell populations was revealed. Intra-mitochondrial ring-like granules characterize type 1 cells when overloaded, while a strong calcium storage is detected in the rough endoplasmic reticulum, Golgi apparatus and mitochondrial (without any inner organization of the deposits) of the type 2 cells. Our results also show the presence of calcium on gap-junctions (revealed) by lanthanum method), and on the extracellular matrix (collagen fibres and complex carbohydrates). The ability of some mitochondria to store calcium (ring-like granules) suggests that the type 1 cells are fully differentiated in odontoblast-like cells and perhaps engaged in mineralization processes. The calcium binding sites, localized on the extracellular matrix may therefore be considered as the earliest foci of calcification.

Calcium↗
PubMed1978

[Gas chromatography analysis of volatile monocarboxylic aliphatic acids (C2 to C6) of 15 strains of Veillonella of oral origin].

A qualitative and quantitative study has been carried out on 15 strains of the Veillonella genus, isolated in the oral cavity. Following two methods of preparation of samples for injection in a chromatograph GL, we have identified among the volatil monocarboxylic aliphatic acids from C2 to C6 the glucose fermentation products of these different strains. With the same methods, we studied in parallel these products from strains A.T.C.C. 10790-17444 (Veillonella parvula) and 17445-17446 and 17447 (Veillonella alcalescens). The results, despite the diversity of origin of all these strains, based on physiological and biochemical characteristics, confirm that volatil monocarboxylic aliphatic acids are characteristic of a genus specificity and not of a species. The presence of acetic acid, proprionic acid and iso-valeric acid was shown

Chromatography, Gas↗
PubMed1976

[Ultrastructural study of human pulp cells cultured in vitro].

Primary cultures from human dental pulp were produced in Leighton tubes in the compound nutritive medium of Eagle consisting of calf serum, ascorbic acid, penicillin and streptomycin. After 2 months, the coverglasses supporting the cultures were recovered and fixed for electron microscopy. The results obtained showed a polarisation of the cells, the presence of a cilium, a highly developed endoplasmic reticulum, a typical Golgi apparatus with coated vesicles in the vicinity, elongated dense secretion vesicles containing a cross-striated filamentous material, numerous mitochondria, microfilaments with thickenings, microtubules, secretion granules, multivesicular bodies and electron dense structures united by a fibre with a periodic cross-striation of 640 A. These cells secreted a collagenous matrix uith an at random fibrillar distribution, fusiform outlines of fibrils (diameters varying from 650 A to 3,600 A), a cross-striation of 640 A and the presence of electron dense zones on the fibrils. "Globules" (with a trilamellar membrane of about 110 A) were identified in the extracellular medium. The possible comparisons between the typical characteristics of these cells and those of the odontoblast and pulpal fibroblasts were discussed.

Cell Nucleus↗
PubMedDate not supplied

[Histological aspects of tooth bleaching technics].

The chemical principles of tooth bleaching are detailed in order to analyze scanning microscopy data obtained following internal and external bleaching tooth bleaching appears harmless to the enamel structure providing no etching is applied prior to bleaching. Previous enamel undermining appears to increase the porosity along preexisting cracks. Internal bleaching gives way to enamel and dentinal demineralization, which is of particular importance at the dento enamel junction. The biological effects of bleaching on dental hard tissues must be viewed in light of the clinical indications for these procedures.

Adult↗