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G Godeau

Publications and source records attributed to G Godeau.

At least 37 records · Page 2Linked to original sources
PubMed2000

Immunohistological and morphometric analysis of intra-epithelial lymphocytes and Langerhans cells in healthy and diseased human gingival tissues.

Periodontal diseases are histologically characterized by an infiltration of several inflammatory cell populations into the gingival epithelium and connective tissue, associated with degradation of extracellular matrix components. The purpose of this in situ study was to evaluate the inflammatory state of gingival tissues by the number of intra-epithelial lymphocyte (IEL) subsets and the area fraction (AA%) occupied by collagen fibres in the upper gingival connective tissue, and also to evaluate the number of CD1a+ Langerhans cells (LC) in order to show correlation(s), if any, between these histological findings. The gingival samples were from 10 clinically healthy controls (group C), 8 patients with gingivitis (group G) and 9 with chronic adult periodontitis (group P). A quantitative evaluation of the number of cell populations (CD1a+, CD45RB+, CD3+, CD8+, CD20+, TIA-1+ and GrB+ cells) and the area fraction (AA%) occupied by collagen fibres in the upper gingival connective tissue was made by morphometric and automated image analysis. The results showed that, compared with group C, all IEL subset numbers were significantly increased (p<0.05) in G and P groups, CD20+ excepted. In addition, there was a significant increase in the cytotoxic TIA-1+ IEL number (p<0.05) in group P when compared with group G. The study also showed a significant decrease in the number of CD1a+ LC in groups G and P (p<0.02 and p<0.001, respectively) when compared with group C. No significant difference was found in CD1a+ LC number between groups G and P. The determination of coefficients of correlation (r) with data obtained for each patient showed that in group G, CD1a+ LC number was significantly correlated with CD45RB+ (p<0.05) and CD3+ (p<0.01) IEL numbers whereas during periodontitis, CD1a+ LC number was significantly and inversely correlated with CD20+ (p<0.01), cytotoxic TIA-1+ (p<0.01) and with activated cytotoxic GrB+ (p<0.01) IEL numbers. Moreover, in group P a significant (p<0.05) positive correlation was shown between CD1a+ LC number and the AA% occupied by collagen fibres. This work demonstrates a decrease in CD1a+ LC number according to the severity of the periodontal disease estimated by the number of IEL and by the area fraction occupied by collagen fibres in human gingiva. The decrease of such cells could represent a way to avoid immune overstimulation.

Adolescent↗
PubMed2000

Quantitative morphological analysis of Langerhans cells in healthy and diseased human gingiva.

Langerhans cells (LC) are implicated in the initiation and maintenance of inflammatory periodontal diseases. The purpose of this immunohistological study using morphometric and automated image analysis was to determine the morphological features of CD1a+ LC in healthy and inflammatory gingiva according to their localisation in the upper epithelium or the basal layer. The study was on gingival samples from 11 healthy controls (C), eight patients with gingivitis (G) and 12 patients with severe chronic adult periodontitis (P). The results show that in the basal layer of all experimental groups, the perimeter, surface and equivalent diameter of CD1a+ LC were significantly decreased (P<0.005) when compared with those in the upper epithelium of the same group. Furthermore, CD1a+ LC had become more rounded, reflected by a significant increase in form factor (P<0.005), when located close to the epithelial basal membrane. In the upper epithelium of group P, the perimeter, surface and equivalent diameter of CD1a+ LC were significantly decreased (P<0. 05) and the form factor significantly increased (P<0.05) when compared with the upper epithelium of group C. This work provides evidence for important morphological variations in CD1a+ LC according to their location within the epithelium and the severity of the periodontal disease. The observed morphological changes may reflect a cellular adaptation during the epithelial transmigration and could eventually be involved in immune stimulation during periodontitis.

Adult↗
PubMed2000

Analysis of the ex vivo specificity of human gelatinases A and B towards skin collagen and elastic fibers by computerized morphometry.

Cutaneous aging and chronic exposure to UV irradiation leads to alterations in the appearance and biochemical composition of the skin. Members of the MMP family have been involved in the destruction of the extracellular matrix. Among them, gelatinases A and B were found to display elastolytic activity, in vitro. In this study, we first determined the ex vivo elastolytic potential of both endopeptidases, using human skin tissue sections and computerized morphometric analyses, and compared it with those of neutrophil elastase. In such conditions, gelatinase B (50 nM) induced 50% elastolysis. The percentage of elastic fibers degraded by gelatinase A (10-100 nM) never exceeded 10%. Elastolysis by gelatinase B and leukocyte elastase was characterized by a decrease in fiber length and an increase in the average diameter of the fibers. In addition, gelatinase B exhibited fibrillin-degrading activities. On the contrary, gelatinase A (50 nM) elicited up to 50% hydrolysis of collagen fibers, preferentially degrading type III collagen fibers. Gelatinase B did not promote any collagen degrading activity. Our data suggested that in vivo gelatinases could disrupt most extracellular matrix structures of human skin. Gelatinase B and to a much lesser extent, gelatinase A would degrade components of the elastic fibers network while gelatinase A, but not gelatinase B, would alter mostly collagen fibers and also degrade constituents of the dermo-epidermal junction.

Collagen↗
PubMed2000

Implication of interleukin-4 in wound healing.

Interleukin-4 (IL-4) is a pleiotropic cytokine that is able to activate connective tissue cells and stimulate the accumulation of extracellular matrix macromolecules. In this report, the expression of IL-4 in normal wound healing was studied by immunohistochemistry. The effects of exogenous IL-4 or IL-4 antisense oligonucleotides administration were also studied in mouse experimental wounds. IL-4 expression was detected in the lower dermis below the wound as early as Day 1 after wounding. IL-4 expression was maximal by Day 4, then decreased progressively, and completely disappeared by Day 21 after wounding. Topical administration of IL-4 on experimental wounds in mice significantly accelerated the rate of healing, whereas IL-4 antisense oligonucleotides significantly inhibited healing. These results demonstrate that IL-4 may be implicated in normal wound healing.

Animals↗
PubMed2000

Collagen fibers and inflammatory cells in healthy and diseased human gingival tissues: a comparative and quantitative study by immunohistochemistry and automated image analysis.

BACKGROUND: Periodontal disease is histologically characterized by the degradation of extracellular matrix components associated with a gingival infiltration of inflammatory cell populations. The purpose of this in situ study was to quantify inflammatory cell subsets and the area fraction (AA%) occupied by collagen fibers in healthy and diseased upper gingival connective tissue in order to investigate the association, if any, between collagen loss and inflammatory cell infiltrate. METHODS: Paraffin gingival tissue sections from 10 healthy controls (C), 9 patients with gingivitis (G), and 10 patients with severe chronic periodontitis (P) were immunohistochemically stained by antibodies against CD45, CD3, CD8, CD20, CD68, TIA-1, and GrB molecules, and the collagen fibers were stained using sirius red F3Ba. The quantitative evaluations of inflammatory cell numbers and the AA% occupied by collagen fibers were performed by morphometric and automated image analysis. RESULTS: In group P, CD45+, CD20+, CD68+, TIA-1+, and GrB+ cell numbers were significantly increased (P<0.05) when compared to both C and G groups. The present study revealed significant differences (P <0.01) between means of AA% observed in group C (63%), group G (46%), and group P (26%), and AA% of group G and group P was inversely correlated with the numbers of TIA-1+ cells (P<0.01) and GrB+ cells (P<0.01 and P<0.05, respectively). CONCLUSIONS: This study showed great differences in the number of the distinct inflammatory cell subsets according to the severity of the periodontal disease and suggested that activated cytotoxic cells could play a pivotal role in the loss of collagen fibers observed during these pathological states. During periodontitis, collagen loss was significantly correlated with all inflammatory cell subset numbers. Finally, the quantitative evaluation of the area fraction occupied by gingival collagen fibers may reflect the clinical severity of the periodontal disease.

Adolescent↗
PubMed1999

Skin elastic fibers in Williams syndrome.

The elastin gene is consistently deleted in Williams syndrome and as this protein represents the major component of the elastic fibers of the dermis, we sought to investigate skin elastic fibers in Williams syndrome as a key to unraveling extracellular matrix disorganization in this condition. Both morphometric parameters analyzed by using automated image analysis and immunofluorescence labeling with monoclonal antibodies against elastin and fibrillin 1 showed a disorganized pre-elastic (oxytalan and elaunin) and mature elastic fibers in the dermis of 10 Williams syndrome patients compared with five healthy children and one patient with isolated supravalvular aortic stenosis. Skin biopsies in Williams syndrome patients provide a simple mean to elucidate extracellular matrix anomalies. Hopefully, this method could give clues to the understanding of the elastic network anomalies in this condition and even to the consequences of these latter on elasticity and resilience of other tissues such as the arterial tree.

Adolescent↗
PubMed1999

Effect of heparin on the production of matrix metalloproteinases and tissue inhibitors of metalloproteinases by human dermal fibroblasts.

The influence of heparin and a heparin fragment devoid of anticoagulant activity on the production of matrix metalloproteinases and tissue inhibitors of metalloproteinases by human dermal fibroblasts was studied. Doses (0.1-400 microg/ml) responses were performed and data obtained were similar whatever heparin or fragment was used. The basal expression of collagenase by fibroblasts decreased quasi-linearly with increasing doses of heparins from 1 to 400 microg/ml. TIMP-1 levels were not affected by supplementing serum free culture medium with heparins. On the contrary, at low concentration, i.e. 1-10 microg/ml, heparins stimulated the secretion of both 72-kDa gelatinase (1.4-1.6-fold) and particularly TIMP-2 (>4-fold). At high doses, MMP-2 and TIMP-2 production by fibroblasts returned to basal levels. These results suggested that the local concentration of heparin released by mast cells could be instrumental in modulating fibroblast growth and proteolytic phenotype.

Adolescent↗
PubMed1999

[3H]choline uptake and turnover into membrane and extracellular matrix phospholipids, visualized by radioautography in rat incisor dentin and enamel.

In order to study the uptake and fate of [3H]choline into cellular and extracellular phospholipids in the forming part of mandibular rat incisors, radioautography was carried out after treatment with the iodoplatinate reaction which retains phospholipids. Thirty minutes and 1 hour after the intravenous injection of the radiolabeled precursor, grain density in secretory odontoblasts and ameloblasts was not significantly above background labeling whereas dentin was actually labeled. Therefore, at this early period, odontoblasts cannot be responsible for the secretion of phospholipids incorporated into dentin, and intercellular diffusion of components originating from blood could explain this early dentin labeling. After 2 hours, odontoblasts and ameloblasts were labeled. In cells, grain density reached a maximum at 4 hours, reduced at 24 hours, and strongly decreased at 4 days. In predentin and enamel, grain density peaked at 24 hours and diminished at 4 days. However, in the forming enamel 4 days after the injection, labeling was twice as high as in any other compartment. Altogether, the results highlighted two distinct pathways for phospholipids in dental mineralized dental tissues: a first one shows evidence of early incorporation of [3H]choline into dentin resulting from intercellular diffusion independently from odontoblasts secretion, whereas inside the forming enamel, higher labeling and longer retention of choline-containing membrane components were detected between 4 hours and 4 days. This suggests an accumulation of membranes that are not subjected to rapid turnover in contrast with other dental compartments.

Ameloblasts↗
PubMed1999

Increased fibroblast elastase activity in acquired cutis laxa.

BACKGROUND: Acquired cutis laxa is a rare disease characterized by sagging skin, premature wrinkling and reduced skin elasticity. OBSERVATION: We report a 21-year-old woman, who presented with acquired cutis laxa on the face and the ear lobes. Urticarial papules had preceded for 6 years. There was no systemic involvement. Skin specimens were obtained from lax skin and urticarial papules, and from healthy controls. Histology showed only few perivascular lymphocytes in lax ear skin and a dense inflammatory infiltrate in urticarial skin. In both biopsies elastic fibres were decreased as demonstrated by computerized morphometric analyses. Elastase activities of fibroblasts in culture were evaluated. There was a 2- to 3-fold increase in elastase activity in urticarial skin fibroblasts, contrasting with a normal elastase activity in lax ear skin. CONCLUSION: Our findings suggest that the inflammatory cells could play a significant role in the destruction of elastic fibres.

Adult↗
PubMed1999

Immunohistologic and morphometric analysis of cytotoxic T lymphocytes in gingivitis.

BACKGROUND: Gingivitis is an inflammatory phenomenon localized in gingival tissues and histologically characterized by an infiltration of several inflammatory cell populations. The purpose of this study was to characterize, localize, and quantify in situ inflammatory and cytotoxic T lymphocytes using immunolabeled gingival tissue sections in order to specify their implication during human gingivitis, since it is well known that such cells play an important role in the defense against bacterial elements. METHODS: Paraffin gingival tissue sections from 7 patients with gingivitis (G) and from 7 clinically and histologically healthy controls (C) were immunohistochemically stained by specific antibodies (anti-CD45, anti-CD3, anti-CD8, anti-CD20, anti-TIA-1, anti-GrB, and anti-CD68), allowing the quantification of inflammatory cells in upper gingival epithelium (Ep), in the basal epithelium layer (BEp), and in upper connective tissue (CT). Collagen fibers were stained by sirius red F3Ba in order to evaluate, by morphometric and automated image analysis, the surface occupied by collagen bundles and to histologically confirm the absence of pathology of the clinically selected healthy controls. RESULTS: In the gingivitis group, CD45+, CD3+, CD8+, TIA-1+, and GrB+ lymphocyte numbers were significantly increased in Ep (P<0.05); and CD45+, CD3+, and TIA-I+ lymphocyte numbers were significantly increased in BEp (P <0.05) compared respectively to Ep and BEp of group C. In Ep of group G, mean CD8+/CD3+ cell ratio was significantly increased (P<0.05) compared to BEp and CT, and 25% of TIA-1+ cytotoxic cells were activated GrB+ cells. CONCLUSIONS: The present study suggests that intraepithelial cytotoxic T lymphocytes play an important role during gingivitis and CD8 expression and that activation of TIA-1+ cytotoxic cells could be induced in Ep in response to epithelial environment. Thus, gingival epithelial tissue, which is generally only considered as a physical barrier, in fact contains numerous immune cell populations preventing the infiltration of pathogenic elements into the connective tissue. Particular clinical attention must be taken for the preservation of the epithelial tissue integrity.

Adolescent↗
PubMed1999

[Congenital generalized cutis laxa: 5 cases].

BACKGROUND: Congenital cutis laxa is an exceptional condition. No large scale series has been reported in the French literature. We report 5 cases observed between 1993 and 1997. PATIENTS AND METHODS: Five children with a morphotype compatible with congenital generalized cutis laxa were examined. A family study, complete visceral workup and skin biopsy with standard histology, orceine coloration and histomorphometric analysis of the collagen and elastic fibers of the dermis were performed. Karyotype and copper metabolism (cupremia and ceruloplasminemia) were available in 3 children. RESULTS: The diagnosis was clinical and proven histologically by orceine coloration of skin biopsies in all cases. There were discrete ultrastructure anomalies in the pure cutaneous form expressed in case n(o) 1 with possible autosomal dominant inheritance. Cupremia and ceruloplasminemia were normal in the 3 children explored; this corresponds to absence of the Elhers-Danlos type IX phenotype. The karyotype was normal in 3/3 children, in agreement with the absence in these three children of marfanoid cutis laxa phenotype. Patients n(o) 2, 3, 4 and 5 had common features: probable autosomal recessive inheritance and severe prognosis. Patient n(o) 2 died at the age of 3 weeks and had severe pulmonary emphysema. This child's sister also had cutis laxa but with no visceral component (autosomal recessive inheritance with variable expression). Patients n(o) 3, 4 and 5 had a severe multiple malformative syndrome with facial dysmorphism, growth retardation, unexplained digestive disorders and psychomotor retardation. DISCUSSION: Our series of 5 patients and data in the literature confirm that primary cutis laxa is a heterogeneous group of conditions both clinically and genetically. The anomalies associated in patients n(o) 3, 4 and 5 were not directly related to anomalous elastic tissue as was also the case for the craniostenosis in patient n(o) 3 reported in other cases in the literature.

Abnormalities, Multiple↗
PubMed1998

Influence of heparin(s) on the interleukin-1-beta-induced expression of collagenase, stromelysin-1, and tissue inhibitor of metalloproteinase-1 in human gingival fibroblasts.

Here, we describe the influence of heparin(s) on the interleukin-1-beta (IL-1beta)-induced expression of collagenase (matrix metalloproteinase-1, MMP-1), stromelysin-1 (matrix metalloproteinase-3, MMP-3) and tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) in human gingival fibroblasts (HGF). Amounts of secreted enzymes and inhibitors as well as their mRNA steady-state levels increased significantly following supplementation of HGF culture medium with 2 ng/mL of IL-1 beta1. Addition of heparin to cell culture medium 1 hour following IL-1beta decreased MMP and TIMP-1 expression in a dose-dependent manner. The inhibitory effect of heparin was significant at a concentration as low as 1 microg/mL. These findings could be reproduced with a low Mr heparin fragment devoid of anticoagulant activity. Heparin and fragments might therefore reduce the excessive proteolytic capacity of the gingival fibroblast during inflammation and could be useful as pharmacological agent(s) in gingivitis and periodontitis.

Cells, Cultured↗
PubMed1998

Collagen zymography as a sensitive and specific technique for the determination of subpicogram levels of interstitial collagenase.

We describe the use of casting native collagen type I in SDS-polyacrylamide gel (collagen zymography) for the determination of interstitial collagenase. As with gelatin, the incorporation of collagen in the gels reduced protein migration and the need for making corrections for an accurate Mr evaluation. This method proved to be very sensitive: 0.1 pg of APMA-activated procollagenase could be detected, and specific levels of active gelatinase or stromelysin lower than 5 ng were inactive under our experimental conditions. It was used to demonstrate the increased expression of collagenase following treatment of human gingival fibroblasts with interleukin-1 beta; the amounts of enzyme quantified by either collagen zymography or immunodot blot assay are comparable.

Adult↗
PubMed1998

Measurement of the amounts of elastic fibers in the skin and temporal arteries of healthy aged individuals by automated image analysis.

BACKGROUND: A quantitative study of dermal and arterial elastic fibers as a function of age was carried out by computerized image analysis. OBJECTIVE: We investigated whether any parallelism can be established between the morphometric parameters of elastic fibers from the skin and the temporal artery in elderly subjects. METHODS: we quantitated the skin elastic fibers of the reticular dermis and the elastic fibers of the temporal artery using a specific staining procedure followed by automated image analysis in 16 subjects of age range 63-87 years. RESULTS: There was a good correlation between the area fraction occupied by the elastic fibers in the unexposed skin (inner part of the upper arm) and aging (r = 0.669, p < 0.01). The area fraction occupied by elastic fibers in unexposed skin was correlated with the area fraction occupied by elastic fibers in the deep part of the temporal artery (r = 0.498, p < 0.05). Actinic elastosis affected both tissues, but there was no correlation between the amount of elastotic material in the exposed skin and the area fraction of elastic fibers in the superficial part of the temporal artery. CONCLUSION: We provided evidence that in sun-protected tissues the area fraction occupied by elastic fibers in dermis and deep part of the temporal artery showed a significant correlation. We proposed that skin biopsies were a valuable diagnostic tool for predicting arterial wall abnormalities of elastic fibers.

Aged↗
PubMed1998

Morphometric studies of collagen and fibrin lattices contracted by human gingival fibroblasts; comparison with dermal fibroblasts.

Cell shape variations and substratum re-organization during contraction of floating collagen and fibrin lattices seeded with human gingival fibroblasts were determined by computerized image analysis of light and scanning electron microscopic images. Data were compared with those obtained with lattices populated with human dermal fibroblasts. The extent of collagen lattice contraction was similar with both cell types, resulting in a two-fold decrease in the area fractions occupied by collagen fibers. Fibroblasts exhibited a rounded shape (form factors equal to 0.8 and 0.7 for gingival and dermal cells, respectively) at day 1 of culture; they possessed a more elongated appearance (with form factors equal to 0.3 and 0.15 for gingival and dermal cells, respectively) at day 7. Continuous (gingival) and discontinuous (dermal) layers of cells were evidenced at the cortex of lattices. Contractions were associated with a significant reduction of the diameters of collagen fibers. Re-organization of substratum, as analyzed by the "Rose of Directions" technique, was evidenced only at the vicinity of filopodia where fibers ran parallel to these protrusions. Several lysed matrix cavities were observed when fibrin lattices were populated with gingival but not dermal fibroblasts at day 5 of culture. Although cells in fibrin lattices exhibited morphometric parameters comparable with those in collagen lattices, no fibroblast layers could be demonstrated at gel peripheries. Fibrin matrices consisted of an isotropic network of entangled fibrin filaments from the start of culture, and only a slight reduction of the diameters of fibrin fibers could be evidenced in dermal fibroblast-populated lattices. Fibrinolysis at the vicinity of gingival fibroblasts led to an entire re-organization of substratum toward the formation of larger fibers. The differential behavior of gingival vs. dermal fibroblasts inside fibrin but not collagen matrices could therefore partly explain the increased rate of remodeling of gingiva as compared with dermis.

Adult↗
PubMed1998

Fragmentation of the distal portion of Tomes' processes of secretory ameloblasts in the forming enamel of rat incisors.

In order to investigate enamel and dentin phospholipid metabolic pathways, two separate experiments were carried out. Firstly, rats were given chloroquine, a drug which induces a lipidosis-like disease. Extensive accumulation inside lysosomes was seen in all the groups of cells in the forming part of the rat incisor, except secretory ameloblasts which were unaffected by the drug. Secondly, the uptake and fate of 3H-choline were studied by radioautography on rats fed either normally or on an essential fatty acid deficient diet (EFAD). Four hours after the injection of the precursor, incorporation reached a maximum then decreased gradually. At 4 days the forming enamel displayed higher silver grain density than any other compartment. In EFAD rats 3H-choline incorporation was decreased drastically in each compartment except in the forming enamel which was not affected by the deficiency. The longer retention of the labeling in the forming enamel and the lack of lysosomal accumulation in chloroquine-treated secretory ameloblasts support the hypothesis that fragments of the distal Tomes' process are released during enamel formation. Disconnected from the cells, membrane remnants are neither reinternalized nor subjected to further degradation inside lysosomes.

Ameloblasts↗
PubMed1998

Morphometric analysis of human gingival elastic fibres degradation by human leukocyte elastase protective effect of avocado and soybean unsaponifiables (ASU).

Degradation of preelastic fibres (oxytalan and elaunin) and mature elastic fibres by human leukocyte elastase (HLE) was investigated using automated image analysis. Specimens from two young healthy adults were used. Although HLE hydrolyzed both fibre types, mature elastic fibres exhibited greater susceptibility to this effect than preelastic fibres. Avocado and soybean unsaponifiables are widely prescribed in rheumatology and parodontology and have also been the focus of ex vivo experiments aimed at determining whether they protect elastic fibres against degradation by HLE. Findings from the present study indicate that avocado and soybean unsaponifiables protect all types of gingival elastic fibres from degradation by HLE. Avocado and soybean unsaponifiables may be beneficial in patients with gingival inflammation and parodontitis, since HLE plays a major role in these disease states.

Adult↗